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Sample records for tissues cardiovascular flows

  1. Unravelling cardiovascular disease using four dimensional flow cardiovascular magnetic resonance.

    Science.gov (United States)

    Kamphuis, Vivian P; Westenberg, Jos J M; van der Palen, Roel L F; Blom, Nico A; de Roos, Albert; van der Geest, Rob; Elbaz, Mohammed S M; Roest, Arno A W

    2017-07-01

    Knowledge of normal and abnormal flow patterns in the human cardiovascular system increases our understanding of normal physiology and may help unravel the complex pathophysiological mechanisms leading to cardiovascular disease. Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) has emerged as a suitable technique that enables visualization of in vivo blood flow patterns and quantification of parameters that could potentially be of prognostic value in the disease process. In this review, current image processing tools that are used for comprehensive visualization and quantification of blood flow and energy distribution in the heart and great vessels will be discussed. Also, imaging biomarkers extracted from 4D flow CMR will be reviewed that have been shown to distinguish between normal and abnormal flow patterns. Furthermore, current applications of 4D flow CMR in the heart and great vessels will be discussed, showing its potential as an additional diagnostic modality which could aid in disease management and timing of surgical intervention.

  2. Bioreactor Technology in Cardiovascular Tissue Engineering

    Science.gov (United States)

    Mertsching, H.; Hansmann, J.

    Cardiovascular tissue engineering is a fast evolving field of biomedical science and technology to manufacture viable blood vessels, heart valves, myocar-dial substitutes and vascularised complex tissues. In consideration of the specific role of the haemodynamics of human circulation, bioreactors are a fundamental of this field. The development of perfusion bioreactor technology is a consequence of successes in extracorporeal circulation techniques, to provide an in vitro environment mimicking in vivo conditions. The bioreactor system should enable an automatic hydrodynamic regime control. Furthermore, the systematic studies regarding the cellular responses to various mechanical and biochemical cues guarantee the viability, bio-monitoring, testing, storage and transportation of the growing tissue.

  3. Cardiovascular Tissue Engineering: Preclinical Validation to Bedside Application

    Science.gov (United States)

    Best, Cameron; Onwuka, Ekene; Pepper, Victoria; Sams, Malik; Breuer, Jake

    2015-01-01

    Advancements in biomaterial science and available cell sources have spurred the translation of tissue-engineering technology to the bedside, addressing the pressing clinical demands for replacement cardiovascular tissues. Here, the in vivo status of tissue-engineered blood vessels, heart valves, and myocardium is briefly reviewed, illustrating progress toward a tissue-engineered heart for clinical use. PMID:26661524

  4. Decellularized matrices for cardiovascular tissue engineering.

    Science.gov (United States)

    Moroni, Francesco; Mirabella, Teodelinda

    2014-01-01

    Cardiovascular disease (CVD) is one of the leading causes of death in the Western world. The replacement of damaged vessels and valves has been practiced since the 1950's. Synthetic grafts, usually made of bio-inert materials, are long-lasting and mechanically relevant, but fail when it comes to "biointegration". Decellularized matrices, instead, can be considered biological grafts capable of stimulating in vivo migration and proliferation of endothelial cells (ECs), recruitment and differentiation of mural cells, finally, culminating in the formation of a biointegrated tissue. Decellularization protocols employ osmotic shock, ionic and non-ionic detergents, proteolitic digestions and DNase/RNase treatments; most of them effectively eliminate the cellular component, but show limitations in preserving the native structure of the extracellular matrix (ECM). In this review, we examine the current state of the art relative to decellularization techniques and biological performance of decellularized heart, valves and big vessels. Furthermore, we focus on the relevance of ECM components, native and resulting from decellularization, in mediating in vivo host response and determining repair and regeneration, as opposed to graft corruption.

  5. Micro- and nanotechnology in cardiovascular tissue engineering

    International Nuclear Information System (INIS)

    Zhang Boyang; Xiao Yun; Hsieh, Anne; Thavandiran, Nimalan; Radisic, Milica

    2011-01-01

    While in nature the formation of complex tissues is gradually shaped by the long journey of development, in tissue engineering constructing complex tissues relies heavily on our ability to directly manipulate and control the micro-cellular environment in vitro. Not surprisingly, advancements in both microfabrication and nanofabrication have powered the field of tissue engineering in many aspects. Focusing on cardiac tissue engineering, this paper highlights the applications of fabrication techniques in various aspects of tissue engineering research: (1) cell responses to micro- and nanopatterned topographical cues, (2) cell responses to patterned biochemical cues, (3) controlled 3D scaffolds, (4) patterned tissue vascularization and (5) electromechanical regulation of tissue assembly and function.

  6. Adipose tissue, the skeleton and cardiovascular disease

    International Nuclear Information System (INIS)

    Wiklund, Peder

    2011-01-01

    Cardiovascular disease (CVD) is the leading cause of death in the Western World, although the incidence of myocardial infarction (MI) has declined over the last decades. However, obesity, which is one of the most important risk factors for CVD, is increasingly common. Osteoporosis is also on the rise because of an aging population. Based on considerable overlap in the prevalence of CVD and osteoporosis, a shared etiology has been proposed. Furthermore, the possibility of interplay between the skeleton and adipose tissue has received increasing attention the last few years with the discovery that leptin can influence bone metabolism and that osteocalcin can influence adipose tissue. A main aim of this thesis was to investigate the effects of fat mass distribution and bone mineral density on the risk of MI. Using dual-energy x-ray absorptiometry (DEXA) we measured 592 men and women for regional fat mass in study I. In study II this was expanded to include 3258 men and women. In study III 6872 men and women had their bone mineral density measured in the total hip and femoral neck using DEXA. We found that a fat mass distribution with a higher proportion of abdominal fat mass was associated with both an adverse risk factor profile and an increased risk of MI. In contrast, a higher gynoid fat mass distribution was associated with a more favorable risk factor profile and a decreased risk of MI, highlighting the different properties of abdominal and gynoid fat depots (study I-II). In study III, we investigated the association of bone mineral density and risk factors shared between CVD and osteoporosis, and risk of MI. We found that lower bone mineral density was associated with hypertension, and also tended to be associated to other CVD risk factors. Low bone mineral density was associated with an increased risk of MI in both men and women, apparently independently of the risk factors studied (study III). In study IV, we investigated 50 healthy, young men to determine if

  7. Adipose tissue, the skeleton and cardiovascular disease

    Energy Technology Data Exchange (ETDEWEB)

    Wiklund, Peder

    2011-07-01

    Cardiovascular disease (CVD) is the leading cause of death in the Western World, although the incidence of myocardial infarction (MI) has declined over the last decades. However, obesity, which is one of the most important risk factors for CVD, is increasingly common. Osteoporosis is also on the rise because of an aging population. Based on considerable overlap in the prevalence of CVD and osteoporosis, a shared etiology has been proposed. Furthermore, the possibility of interplay between the skeleton and adipose tissue has received increasing attention the last few years with the discovery that leptin can influence bone metabolism and that osteocalcin can influence adipose tissue. A main aim of this thesis was to investigate the effects of fat mass distribution and bone mineral density on the risk of MI. Using dual-energy x-ray absorptiometry (DEXA) we measured 592 men and women for regional fat mass in study I. In study II this was expanded to include 3258 men and women. In study III 6872 men and women had their bone mineral density measured in the total hip and femoral neck using DEXA. We found that a fat mass distribution with a higher proportion of abdominal fat mass was associated with both an adverse risk factor profile and an increased risk of MI. In contrast, a higher gynoid fat mass distribution was associated with a more favorable risk factor profile and a decreased risk of MI, highlighting the different properties of abdominal and gynoid fat depots (study I-II). In study III, we investigated the association of bone mineral density and risk factors shared between CVD and osteoporosis, and risk of MI. We found that lower bone mineral density was associated with hypertension, and also tended to be associated to other CVD risk factors. Low bone mineral density was associated with an increased risk of MI in both men and women, apparently independently of the risk factors studied (study III). In study IV, we investigated 50 healthy, young men to determine if

  8. Low oxygen concentrations impair tissue development in tissue-engineered cardiovascular constructs

    NARCIS (Netherlands)

    Vlimmeren, M.A.A. van; Driessen-Mol, A.; Oomens, C.W.J.; Broek, M. van den; Stoop, R.; Bouten, C.V.C.; Baaijens, F.P.T.

    2012-01-01

    Cardiovascular tissue engineering has shown considerable progress, but in vitro tissue conditioning to stimulate the development of a functional extracellular matrix still needs improvement. We investigated the environmental factor oxygen concentration for its potential to increase the amount of

  9. 3D Bioprinting and In Vitro Cardiovascular Tissue Modeling.

    Science.gov (United States)

    Jang, Jinah

    2017-08-18

    Numerous microfabrication approaches have been developed to recapitulate morphologically and functionally organized tissue microarchitectures in vitro; however, the technical and operational limitations remain to be overcome. 3D printing technology facilitates the building of a construct containing biomaterials and cells in desired organizations and shapes that have physiologically relevant geometry, complexity, and micro-environmental cues. The selection of biomaterials for 3D printing is considered one of the most critical factors to achieve tissue function. It has been reported that some printable biomaterials, having extracellular matrix-like intrinsic microenvironment factors, were capable of regulating stem cell fate and phenotype. In particular, this technology can control the spatial positions of cells, and provide topological, chemical, and complex cues, allowing neovascularization and maturation in the engineered cardiovascular tissues. This review will delineate the state-of-the-art 3D bioprinting techniques in the field of cardiovascular tissue engineering and their applications in translational medicine. In addition, this review will describe 3D printing-based pre-vascularization technologies correlated with implementing blood perfusion throughout the engineered tissue equivalent. The described engineering method may offer a unique approach that results in the physiological mimicry of human cardiovascular tissues to aid in drug development and therapeutic approaches.

  10. Strain-induced tissue growth laws: applications to embryonic cardiovascular development.

    Science.gov (United States)

    Rugonyi, Sandra

    2013-02-28

    Hemodynamic conditions play an essential role in the cardiovascular system, with abnormal blood flow conditions leading to growth and remodeling of cardiovascular walls. During embryonic development, altered hemodynamic conditions lead to congenital heart disease, which affects about 1% of newborn babies in developed countries. However, the mechanisms by which hemodynamic conditions affect cardiovascular development have not been fully elucidated. In this paper, we propose a model of cardiac growth in response to hemodynamic conditions, in which growth is modulated by a combination of wall strains and wall shear stresses. This is in contrast to previous models that proposed stress-induced growth laws. Because during embryonic development blood pressure increases over time, and this increase in blood pressure produces an increase in wall stresses, stress-induced growth laws would require time-dependent parameters. While blood pressure increases during development, cardiovascular walls become stiffer and thicker, and thus we postulate that instead strains experienced by cells remain approximately the same during development. This assumption motivated our cardioavascular model of strain-induced growth in response to hemodynamic conditions, which we implemented using finite element methods. Model simulations show that the proposed model results in tissue growth that is physiologically reasonable. Further, our analyses demonstrate that mechanical coupling - that results from residual stresses originating from differential tissue growth - may play a more important role in the modulation of cardiovascular tissue growth and remodeling than currently acknowledged.

  11. Novel blood protein based scaffolds for cardiovascular tissue engineering

    Directory of Open Access Journals (Sweden)

    Kuhn Antonia I.

    2016-09-01

    Full Text Available A major challenge in cardiovascular tissue engineering is the fabrication of scaffolds, which provide appropriate morphological and mechanical properties while avoiding undesirable immune reactions. In this study electrospinning was used to fabricate scaffolds out of blood proteins for cardiovascular tissue engineering. Lyophilised porcine plasma was dissolved in deionised water at a final concentration of 7.5% m/v and blended with 3.7% m/v PEO. Electrospinning resulted in homogeneous fibre morphologies with a mean fibre diameter of 151 nm, which could be adapted to create macroscopic shapes (mats, tubes. Cross-linking with glutaraldehyde vapour improved the long-term stability of protein based scaffolds in comparison to untreated scaffolds, resulting in a mass loss of 41% and 96% after 28 days of incubation in aqueous solution, respectively.

  12. Flow imaging of the cardiovascular system using magnetic resonance imaging

    International Nuclear Information System (INIS)

    Imai, Hitoshi; Sakakibara, Makoto; Sunami, Yuko

    1988-01-01

    Blood flow images by magnetic resonance imaging (MRI) using a 0.25 T unit were evaluated for nine normal volunteers and 108 subjects with a variety of cardiovascular abnormalities. Using the non-gated short-spin echo (SE) technique, blood flow in the cardiovascular systems was not imaged in the normal volunteers. Using end-systolic and end-diastolic SE techniques for the normal subjects, blood flow in the cardiac chambers was not clearly imaged. Blood flow in the ascending aorta and aortic arch often did not appear in the gated SE images of the normal subjects. However, blood flow in the descending aorta was often observed in the gated SE images. Blood flow imaging was demonstrated by both non-gated and gated SE techniques in regions where blood flow was relatively slow; for example, in the left atrium of mitral stenosis, in an aortic aneurysm, in a false lumen of an aortic dissection, and in the left ventricle having old myocardial infarction. Using the non-gated inversion recovery (IR) technique, no blood flow was imaged in the cardiovascular system except in the left atrium of one case with mitral stenosis. Using the non-gated short SE technique, there was good correlation between the thrombus formation and the presence of blood flow images in the left atria of 17 patients with mitral stenosis, and in the aneurysmal portions of the aorta or in the false lumens of aortic dissection of 18 patients. It was suggested that mural thrombi in such diseases were related to the relatively slow blood flow. Blood flow imaging easily distinguished stagnant blood flow from mural thrombi using non-gated short SE, end-systolic SE, and IR techniques. Thus, blood flow imaging using MRI should become an important means of evaluating the cardiovascular system. (author)

  13. Synthetic aperture tissue and flow ultrasound imaging

    DEFF Research Database (Denmark)

    Nikolov, Svetoslav

    imaging applied to medical ultrasound. It is divided into two major parts: tissue and blood flow imaging. Tissue imaging using synthetic aperture algorithms has been investigated for about two decades, but has not been implemented in medical scanners yet. Among the other reasons, the conventional scanning...... and beamformation methods are adequate for the imaging modalities in clinical use - the B-mode imaging of tissue structures, and the color mapping of blood flow. The acquisition time, however, is too long, and these methods fail to perform real-time three-dimensional scans. The synthetic transmit aperture......, on the other hand, can create a Bmode image with as little as 2 emissions, thus significantly speeding-up the scan procedure. The first part of the dissertation describes the synthetic aperture tissue imaging. It starts with an overview of the efforts previously made by other research groups. A classification...

  14. Exploring the Crosstalk between Adipose Tissue and the Cardiovascular System

    Science.gov (United States)

    2017-01-01

    Obesity is a clinical entity critically involved in the development and progression of cardiovascular disease (CVD), which is characterised by variable expansion of adipose tissue (AT) mass across the body as well as by phenotypic alterations in AT. AT is able to secrete a diverse spectrum of biologically active substances called adipocytokines, which reach the cardiovascular system via both endocrine and paracrine routes, potentially regulating a variety of physiological and pathophysiological responses in the vasculature and heart. Such responses include regulation of inflammation and oxidative stress as well as cell proliferation, migration and hypertrophy. Furthermore, clinical observations such as the “obesity paradox,” namely the fact that moderately obese patients with CVD have favourable clinical outcome, strongly indicate that the biological “quality” of AT may be far more crucial than its overall mass in the regulation of CVD pathogenesis. In this work, we describe the anatomical and biological diversity of AT in health and metabolic disease; we next explore its association with CVD and, importantly, novel evidence for its dynamic crosstalk with the cardiovascular system, which could regulate CVD pathogenesis. PMID:28955384

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

    Science.gov (United States)

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

    2015-01-01

    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 μm-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

  16. Whole Body Bone Tissue and Cardiovascular Risk in Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Claudiu Popescu

    2014-01-01

    Full Text Available Introduction. Atherosclerosis and osteoporosis share an age-independent bidirectional correlation. Rheumatoid arthritis (RA represents a risk factor for both conditions. Objectives. The study aims to evaluate the connection between the estimated cardiovascular risk (CVR and the loss of bone tissue in RA patients. Methods. The study has a prospective cross-sectional design and it includes female in-patients with RA or without autoimmune diseases; bone tissue was measured using whole body dual X-ray absorptiometry (wbDXA; CVR was estimated using SCORE charts and PROCAM applications. Results. There were 75 RA women and 66 normal women of similar age. The wbDXA bone indices correlate significantly, negatively, and age-independently with the estimated CVR. The whole body bone percent (wbBP was a significant predictor of estimated CVR, explaining 26% of SCORE variation along with low density lipoprotein (P < 0.001 and 49.7% of PROCAM variation along with glycemia and menopause duration (P < 0.001. Although obese patients had less bone relative to body composition (wbBP, in terms of quantity their bone content was significantly higher than that of nonobese patients. Conclusions. Female patients with RA and female patients with cardiovascular morbidity have a lower whole body bone percent. Obese female individuals have higher whole body bone mass than nonobese patients.

  17. Understanding the Impact of Arterial Stenosis on Blood Flow through a Tissue

    Science.gov (United States)

    Prakash, Elapulli Sankaranarayanan

    2015-01-01

    This article arises from the author's experience helping medical students apply core biophysical principles toward understanding cardiovascular physiology. The purpose of the article is illustrate how the effect of an arterial stenosis on blood flow to tissue supplied exclusively by the stenosed artery should be assessed. This discussion was…

  18. Immunohistochemical abnormalities of fibrillin in cardiovascular tissues in Marfan's syndrome.

    Science.gov (United States)

    Fleischer, K J; Nousari, H C; Anhalt, G J; Stone, C D; Laschinger, J C

    1997-04-01

    Molecular defects in the glycoprotein fibrillin are believed to be responsible for impaired structural integrity of cardiovascular, skeletal, and ocular tissues in Marfan's syndrome (MFS). Traditionally, excellent results have been achieved with the Bentall composite graft repair of aneurysms of the ascending aorta in MFS. However, because of the potential complications associated with prosthetic valves, there is growing interest in techniques that preserve the native aortic valve. Between May 1994 and February 1995, 15 patients with a history of concomitant or remote aortic root aneurysms or dissection underwent operation for valvular heart disease. Specimens of aortic valve, ascending aortic wall, and mitral valve were obtained specifically to observe differences in fibrillin content and architecture between patients with (n = 9) and without (n = 6) MFS. In addition, control specimens of aortic valve, aortic wall, and mitral valve were obtained from 4 patients with isolated valvular or coronary artery disease but no evidence of connective tissue disorders or other aortic pathologic conditions. Fibrillin immunostaining using indirect immunofluorescence was used. Specimens were coded and graded by a blinded observer to determine quantity, homogeneity, and fragmentation of fibrillin. Observed fibrillin abnormalities in MFS and control patients were limited to the midportion (elastin-associated microfibrils) of the aortic valve, aortic wall, and mitral valve tissues. Fibrillin abnormalities of aortic valve, aortic wall, and mitral valve tissues were seen in all patients with MFS and were most severe in those older than 20 years. Similar fibrillin abnormalities of aortic valve and aortic wall specimens were observed in control patients more than 60 years old. Even in the setting of a normal-appearing aortic valve, the current rationale for widespread use of valve-sparing repairs of aortic root aneurysms in patients with MFS and patients older than 60 years should be

  19. Mathematical modelling of flow distribution in the human cardiovascular system

    Science.gov (United States)

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

    1992-01-01

    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.

  20. Cardiovascular magnetic resonance frontiers: Tissue characterisation with mapping

    Directory of Open Access Journals (Sweden)

    Rebecca Schofield

    2016-11-01

    Full Text Available The clinical use of cardiovascular magnetic resonance (CMR imaging has expanded rapidly over the last decade. Its role in cardiac morphological and functional assessment is established, with perfusion and late gadolinium enhancement (LGE imaging for scar increasingly used in day-to-day clinical decision making. LGE allows a virtual histological assessment of the myocardium, with the pattern of scar suggesting disease aetiology, and the extent of predicting risk. However, even combined, the full range of pathological processes occurring in the myocardium are not interrogated. Mapping is a new frontier where the intrinsic magnetic properties of heart muscle are measured to probe further. T1, T2 and T2* mapping measures the three fundamental tissue relaxation rate constants before contrast, and the extracellular volume (ECV after contrast. These are displayed in colour, often providing an immediate appreciation of pathology. These parameters are differently sensitive to pathologies. Iron (cardiac siderosis, intramyocardial haemorrhage makes T1, T2 and T2* fall. T2 also falls with fat infiltration (Fabry disease. T2 increases with oedema (acute infarction, takotsubo cardiomyopathy, myocarditis, rheumatological disease. Native T1 increases with fibrosis, oedema and amyloid. Some of these changes are large (e.g. iron, oedema, amyloid, others more modest (diffuse fibrosis. They can be used to detect early disease, distinguish aetiology and, in some circumstances, guide therapy. In this review, we discuss these processes, illustrating clinical application and future advances.

  1. Prognostic value of tissue Doppler imaging for predicting ventricular arrhythmias and cardiovascular mortality in ischaemic cardiomyopathy

    DEFF Research Database (Denmark)

    Biering-Sørensen, Tor; Olsen, Flemming Javier; Storm, Katrine

    2016-01-01

    AIMS: Only 30% of patients receiving an implantable cardioverter defibrillator (ICD) for primary prevention receive appropriately therapy. We sought to investigate the value of tissue Doppler imaging (TDI) to predict ventricular tachycardia (VT), ventricular fibrillation (VF), and cardiovascular...

  2. Micro- and nanotechnology in cardiovascular tissue engineering.

    Science.gov (United States)

    Zhang, Boyang; Xiao, Yun; Hsieh, Anne; Thavandiran, Nimalan; Radisic, Milica

    2011-12-09

    While in nature the formation of complex tissues is gradually shaped by the long journey of development, in tissue engineering constructing complex tissues relies heavily on our ability to directly manipulate and control the micro-cellular environment in vitro. Not surprisingly, advancements in both microfabrication and nanofabrication have powered the field of tissue engineering in many aspects. Focusing on cardiac tissue engineering, this paper highlights the applications of fabrication techniques in various aspects of tissue engineering research: (1) cell responses to micro- and nanopatterned topographical cues, (2) cell responses to patterned biochemical cues, (3) controlled 3D scaffolds, (4) patterned tissue vascularization and (5) electromechanical regulation of tissue assembly and function.

  3. Effect of prolonged hypokinesia on tissue blood flow

    Science.gov (United States)

    Levites, Z. P.; Fedotova, V. F.

    1979-01-01

    The influence of hypokinesia on the blood flow in the tissues of rabbits was studied. Motor activity of animals was restricted during 90 days and blood flow recorded through resorption rate of NaI-131. Perfusion of tissues under the influence of hypokinesia was found to be reduced.

  4. Markers of apoptosis in cardiovascular tissues: focus on Annexin V

    NARCIS (Netherlands)

    van Heerde, W. L.; Robert-Offerman, S.; Dumont, E.; Hofstra, L.; Doevendans, P. A.; Smits, J. F.; Daemen, M. J.; Reutelingsperger, C. P.

    2000-01-01

    In the last decade, apoptosis (or programmed cell death) has become appreciated as an important process in the development of the cardiovascular system. Moreover, apoptosis contributes to the adaptation of the system to the environment. We are at the beginning of understanding its relevance to

  5. Intrinsic regulation of blood flow in adipose tissue

    DEFF Research Database (Denmark)

    Henriksen, O; Nielsen, Steen Levin; Paaske, W

    1976-01-01

    Previous studies on intact human subcutaneous tissue have shown, that blood flow remains constant during minor changes in perfusion pressure. This so-called autoregulatory response has not been demonstrable in isolated preparations of adipose tissue. In the present study on isolated, denervated...... subcutaneous tissue in female rabbits only 2 of 12 expts. revealed an autoregulatory response during reduction in arterial perfusion pressure. Effluent blood flow from the tissue in the control state was 15.5 ml/100 g-min (S.D. 6.4, n = 12) corresponding to slight vasodilatation of the exposed tissue...... is more susceptible to surgical exposure of the tissue. During elevation of arterial perfusion pressure blood flow in the isolated tissue showed a transient increase and then almost returned to the level during normotension, indicating an elevated vascular resistance. Raising of venous pressure elicited...

  6. New imaging tools in cardiovascular medicine: computational fluid dynamics and 4D flow MRI.

    Science.gov (United States)

    Itatani, Keiichi; Miyazaki, Shohei; Furusawa, Tokoki; Numata, Satoshi; Yamazaki, Sachiko; Morimoto, Kazuki; Makino, Rina; Morichi, Hiroko; Nishino, Teruyasu; Yaku, Hitoshi

    2017-11-01

    Blood flow imaging is a novel technology in cardiovascular medicine and surgery. Today, two types of blood flow imaging tools are available: measurement-based flow visualization including 4D flow MRI (or 3D cine phase-contrast magnetic resonance imaging), or echocardiography flow visualization software, and computer flow simulation modeling based on computational fluid dynamics (CFD). MRI and echocardiography flow visualization provide measured blood flow but have limitations in temporal and spatial resolution, whereas CFD flow calculates the flow according to assumptions instead of flow measurement, and it has sufficiently fine resolution up to the computer memory limit, and it enables even virtual surgery when combined with computer graphics. Blood flow imaging provides profound insight into the pathophysiology of cardiovascular diseases, because it quantifies and visualizes mechanical stress on the vessel walls or heart ventricle. Wall shear stress (WSS) is a stress on the endothelial wall caused by the near wall blood flow, and it is thought to be a predictor of atherosclerosis progression in coronary or aortic diseases. Flow energy loss (EL) is the loss of blood flow energy caused by viscous friction of turbulent diseased flow, and it is expected to be a predictor of ventricular workload on various heart diseases including heart valve disease, cardiomyopathy, and congenital heart diseases. Blood flow imaging can provide useful information for developing predictive medicine in cardiovascular diseases, and may lead to breakthroughs in cardiovascular surgery, especially in the decision-making process.

  7. Cardiovascular magnetic resonance frontiers: Tissue characterisation with mapping

    OpenAIRE

    Rebecca Schofield; Anish Bhuva; Katia Manacho; James C. Moon

    2016-01-01

    The clinical use of cardiovascular magnetic resonance (CMR) imaging has expanded rapidly over the last decade. Its role in cardiac morphological and functional assessment is established, with perfusion and late gadolinium enhancement (LGE) imaging for scar increasingly used in day-to-day clinical decision making. LGE allows a virtual histological assessment of the myocardium, with the pattern of scar suggesting disease aetiology, and the extent of predicting risk. However, even combined, the ...

  8. Impact of the cardiovascular system-associated adipose tissue on atherosclerotic pathology.

    Science.gov (United States)

    Chistiakov, Dimitry A; Grechko, Andrey V; Myasoedova, Veronika A; Melnichenko, Alexandra A; Orekhov, Alexander N

    2017-08-01

    Cardiac obesity makes an important contribution to the pathogenesis of cardiovascular disease. One of the important pathways of this contribution is the inflammatory process that takes place in the adipose tissue. In this review, we consider the role of the cardiovascular system-associated fat in atherosclerotic cardiovascular pathology and a non-atherosclerotic cause of coronary artery disease, such as atrial fibrillation. Cardiovascular system-associated fat not only serves as the energy store, but also releases adipokines that control local and systemic metabolism, heart/vascular function and vessel tone, and a number of vasodilating and anti-inflammatory substances. Adipokine appears to play an important protective role in cardiovascular system. Under chronic inflammation conditions, the repertoire of signaling molecules secreted by cardiac fat can be altered, leading to a higher amount of pro-inflammatory messengers, vasoconstrictors, profibrotic modulators. This further aggravates cardiovascular inflammation and leads to hypertension, induction of the pathological tissue remodeling and cardiac fibrosis. Contemporary imaging techniques showed that epicardial fat thickness correlates with the visceral fat mass, which is an established risk factor and predictor of cardiovascular disease in obese subjects. However, this correlation is no longer present after adjustment for other covariates. Nevertheless, recent studies showed that pericardial fat volume and epicardial fat thickness can probably serve as a better indicator for atrial fibrillation. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Psoriasis strikes back! Epicardial adipose tissue: another contributor to the higher cardiovascular risk in psoriasis.

    Science.gov (United States)

    Raposo, Inês; Torres, Tiago

    2015-10-01

    For many years psoriasis was considered an inflammatory condition restricted to the skin. However, nowadays it is considered an immune-mediated, systemic inflammatory condition associated with numerous medical comorbidities, particularly cardiometabolic diseases, and overall cardiovascular mortality. Several studies have suggested that psoriasis may be an independent risk factor for atherosclerosis, indicating that psoriasis itself poses an intrinsic risk for cardiovascular disease, probably due to the disease's inflammatory burden. However, other causes beyond systemic inflammation and traditional cardiovascular risk factors may be implicated in cardiovascular disease in psoriasis. Recently, epicardial adipose tissue, an emerging cardiovascular risk factor, has been shown to be increased in psoriasis patients and to be associated with subclinical atherosclerosis, providing another possible link between psoriasis and atherosclerosis. The reason for the increase in epicardial adipose tissue in patients with psoriasis is unknown, but it is probably multifactorial, with genetic, immune-mediated and behavioral factors having a role. Thus, along with the increased prevalence of cardiometabolic risk factors and systemic inflammation in psoriasis, epicardial adipose tissue is probably another important contributor to the higher cardiovascular risk observed in psoriasis. Copyright © 2015 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  10. From Microscale Devices to 3D Printing: Advances in Fabrication of 3D Cardiovascular Tissues

    Science.gov (United States)

    Borovjagin, Anton V.; Ogle, Brenda; Berry, Joel; Zhang, Jianyi

    2016-01-01

    Current strategies for engineering cardiovascular cells and tissues have yielded a variety of sophisticated tools for studying disease mechanisms, for development of drug therapies, and for fabrication of tissue equivalents that may have application in future clinical use. These efforts are motivated by the need to extend traditional two-dimensional (2D) cell culture systems into 3D to more accurately replicate in vivo cell and tissue function of cardiovascular structures. Developments in microscale devices and bioprinted 3D tissues are beginning to supplant traditional 2D cell cultures and pre-clinical animal studies that have historically been the standard for drug and tissue development. These new approaches lend themselves to patient-specific diagnostics, therapeutics, and tissue regeneration. The emergence of these technologies also carries technical challenges to be met before traditional cell culture and animal testing become obsolete. Successful development and validation of 3D human tissue constructs will provide powerful new paradigms for more cost effective and timely translation of cardiovascular tissue equivalents. PMID:28057791

  11. Cardiovascular tissue engineering and regeneration based on adipose tissue-derived stem/stromal cells

    NARCIS (Netherlands)

    Parvizi, Mojtaba

    2016-01-01

    Currently, the pre-clinical field is rapidly progressing in search of new therapeutic modalities that replace or complement current medication to treat cardiovascular disease. Among these are the single or combined use of stem cells, biomaterials and instructive factors, which together form the

  12. Chronic intermittent hypoxia activates nuclear factor-κB in cardiovascular tissues in vivo

    International Nuclear Information System (INIS)

    Greenberg, Harly; Ye Xiaobing; Wilson, David; Htoo, Aung K.; Hendersen, Todd; Liu Shufang

    2006-01-01

    Obstructive sleep apnea (OSA) is an important risk factor for cardiovascular morbidity and mortality. The mechanisms through which OSA promotes the development of cardiovascular disease are poorly understood. In this study, we tested the hypotheses that chronic exposure to intermittent hypoxia and reoxygenation (CIH) is a major pathologic factor causing cardiovascular inflammation, and that CIH-induces cardiovascular inflammation and pathology by activating the NF-κB pathway. We demonstrated that exposure of mice to CIH activated NF-κB in cardiovascular tissues, and that OSA patients had markedly elevated monocyte NF-κB activity, which was significantly decreased when obstructive apneas and their resultant CIH were eliminated by nocturnal CPAP therapy. The elevated NF-κB activity induced by CIH is accompanied by and temporally correlated to the increased expression of iNOS protein, a putative and important NF-κB-dependent gene product. Thus, CIH-mediated NF-κB activation may be a molecular mechanism linking OSA and cardiovascular pathologies seen in OSA patients

  13. Tissue Doppler echocardiography predicts acute myocardial infarction, heart failure, and cardiovascular death in the general population

    DEFF Research Database (Denmark)

    Mogelvang, Rasmus; Biering-Sørensen, Tor; Jensen, Jan Skov

    2015-01-01

    AIMS: To improve risk prediction of cardiovascular morbidity and mortality, we need sensitive markers of cardiac dysfunction; Echocardiographic Tissue Doppler Imaging (TDI) is feasible and harmless and may be ideal for this purpose. METHODS AND RESULTS: Within the community-based Copenhagen City...... with a normal conventional echocardiographic examination [per cm/s decrease: HR 1.18 (1.08-1.28), P general population, TDI identifies individuals with cardiac dysfunction and high risk of cardiovascular morbidity and mortality independently of traditional risk factors, even...

  14. Carotid flow velocity/diameter ratio is a predictor of cardiovascular events in hypertensive patients

    DEFF Research Database (Denmark)

    Bellinazzi, Vera R; Cipolli, José A; Pimenta, Marcio V

    2015-01-01

    OBJECTIVE: The aim of this study was to evaluate the performance of common carotid artery diameter, flow velocity and flow velocity/artery diameter ratio as predictors of major adverse cardiovascular events (MACEs) in a sample of hypertensive patients. METHODS: A cohort of 403 hypertensive patien...

  15. Adipose tissue and skeletal muscle blood flow during mental stress

    Energy Technology Data Exchange (ETDEWEB)

    Linde, B.; Hjemdahl, P.; Freyschuss, U.; Juhlin-Dannfelt, A.

    1989-01-01

    Mental stress (a modified Stroop color word conflict test (CWT)) increased adipose tissue blood flow (ATBF; 133Xe clearance) by 70% and reduced adipose tissue vascular resistance (ATR) by 25% in healthy male volunteers. The vasculatures of adipose tissue (abdomen as well as thigh), skeletal muscle of the calf (133Xe clearance), and the entire calf (venous occlusion plethysmography) responded similarly. Arterial epinephrine (Epi) and glycerol levels were approximately doubled by stress. Beta-Blockade by metoprolol (beta 1-selective) or propranolol (nonselective) attenuated CWT-induced tachycardia similarly. Metoprolol attenuated stress-induced vasodilation in the calf and tended to do so in adipose tissue. Propranolol abolished vasodilation in the calf and resulted in vasoconstriction during CWT in adipose tissue. Decreases in ATR, but not in skeletal muscle or calf vascular resistances, were correlated to increases in arterial plasma glycerol (r = -0.42, P less than 0.05), whereas decreases in skeletal muscle and calf vascular resistances, but not in ATR, were correlated to increases in arterial Epi levels (r = -0.69, P less than 0.01; and r = -0.43, P less than 0.05, respectively). The results suggest that mental stress increases nutritive blood flow in adipose tissue and skeletal muscle considerably, both through the elevation of perfusion pressure and via vasodilatation. Withdrawal of vasoconstrictor nerve activity, vascular beta 2-adrenoceptor stimulation by circulating Epi, and metabolic mechanisms (in adipose tissue) may contribute to the vasodilatation.

  16. Cardiovascular cine imaging and flow evaluation using Fast Interrupted Steady-State (FISS) magnetic resonance.

    Science.gov (United States)

    Edelman, Robert R; Serhal, Ali; Pursnani, Amit; Pang, Jianing; Koktzoglou, Ioannis

    2018-02-19

    Existing cine imaging techniques rely on balanced steady-state free precession (bSSFP) or spoiled gradient-echo readouts, each of which has limitations. For instance, with bSSFP, artifacts occur from rapid through-plane flow and off-resonance effects. We hypothesized that a prototype cine technique, radial fast interrupted steady-state (FISS), could overcome these limitations. The technique was compared with standard cine bSSFP for cardiac function, coronary artery conspicuity, and aortic valve morphology. Given its advantageous properties, we further hypothesized that the cine FISS technique, in combination with arterial spin labeling (ASL), could provide an alternative to phase contrast for visualizing in-plane flow patterns within the aorta and branch vessels. The study was IRB-approved and subjects provided consent. Breath-hold cine FISS and bSSFP were acquired using similar imaging parameters. There was no significant difference in biplane left ventricular ejection fraction or cardiac image quality between the two techniques. Compared with cine bSSFP, cine FISS demonstrated a marked decrease in fat signal which improved conspicuity of the coronary arteries, while suppression of through-plane flow artifact on thin-slice cine FISS images improved visualization of the aortic valve. Banding artifacts in the subcutaneous tissues were reduced. In healthy subjects, dynamic flow patterns were well visualized in the aorta, coronary and renal arteries using cine FISS ASL, even when the slice was substantially thicker than the vessel diameter. Cine FISS demonstrates several benefits for cardiovascular imaging compared with cine bSSFP, including better suppression of fat signal and reduced artifacts from through-plane flow and off-resonance effects. The main drawback is a slight (~ 20%) decrease in temporal resolution. In addition, preliminary results suggest that cine FISS ASL provides a potential alternative to phase contrast techniques for in-plane flow

  17. The interplay between adipose tissue and the cardiovascular system: is fat always bad?

    Science.gov (United States)

    Akoumianakis, Ioannis; Antoniades, Charalambos

    2017-07-01

    Obesity is a risk factor for cardiovascular disease (CVD). However, clinical research has revealed a paradoxically protective role for obesity in patients with chronic diseases including CVD, suggesting that the biological 'quality' of adipose tissue (AT) may be more important than overall AT mass or body weight. Importantly, AT is recognised as a dynamic organ secreting a wide range of biologically active adipokines, microRNAs, gaseous messengers, and other metabolites that affect the cardiovascular system in both endocrine and paracrine ways. Despite being able to mediate normal cardiovascular function under physiological conditions, AT undergoes a phenotypic shift characterised by acquisition of pro-oxidant and pro-inflammatory properties in cases of CVD. Crucially, recent evidence suggests that AT depots such as perivascular AT and epicardial AT are able to modify their phenotype in response to local signals of vascular and myocardial origin, respectively. Utilisation of this unique property of certain AT depots to dynamically track cardiovascular biology may reveal novel diagnostic and prognostic tools against CVD. Better understanding of the mechanisms controlling the 'quality' of AT secretome, as well as the communication links between AT and the cardiovascular system, is required for the efficient management of CVD. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

  18. Adipose tissue, inflammation and cardiovascular disease Tecido adiposo, inflamação e doença cardiovascular

    Directory of Open Access Journals (Sweden)

    Dimas Ikeoka

    2010-01-01

    Full Text Available Obesity has become a very frequent condition with important consequences for the health of affected individuals. Current evidence shows that the excess of adipose tissue as observed in obesity is responsible for secreting inflammatory mediators in a deregulated manner, thus inducing a chronic state of systemic low-grade inflammation that underlies the metabolic and cardiovascular outcomes in these populations. This article reviews the state of the art regarding mediators produced in the adipose tissue, their roles in the pathophysiology of obesity-associated insulin resistance and diabetes, and finally, tries to build a bridge between these mechanistically oriented insights and clinical practice.Obesidade é uma condição frequente com importantes consequencias para a saúde dos indivíduos acometidos. Evidência atual tem demonstrado que o excesso de tecido adiposo, tal qual observado na obesidade, é responsável pela secreção de mediadores inflamatorio de forma descontrolada, levando assim a um estado crônico de inflamação sistêmica de baixa intensidade que está por trás das consequências metabólicas e cardiovasculares em tais populações. Este artigo revisa o estado da arte referente aos mediadores produzidos no tecido adiposo, seus papeis na fisiopatologia da resistência insulínica relacionada à obesidade e ao diabetes, e por fim, tenta estabelecer uma ponte de ligação entre estes conceitos mecanisticamente orientados e a prática clínica.

  19. Epicardial adipose tissue is related to arterial stiffness and inflammation in patients with cardiovascular disease and type 2 diabetes

    OpenAIRE

    Al-Talabany, Shaween; Mordi, Ify; Graeme Houston, J.; Colhoun, Helen M.; Weir-McCall, Jonathan R.; Matthew, Shona Z.; Looker, Helen C.; Levin, Daniel; Belch, Jill J. F.; Dove, Fiona; Khan, Faisel; Lang, Chim C.

    2018-01-01

    Background Epicardial adipose tissue (EAT) is an emerging cardio-metabolic risk factor and has been shown to correlate with adverse cardiovascular (CV) outcome; however the underlying pathophysiology of this link is not well understood. The aim of this study was to evaluate the relationship between EAT and a comprehensive panel of cardiovascular risk biomarkers and pulse wave velocity (PWV) and indexed left ventricular mass (LVMI) in a cohort of patients with cardiovascular disease (CVD) and ...

  20. Epicardial adipose tissue is related to arterial stiffness and inflammation in patients with cardiovascular disease and type 2 diabetes

    OpenAIRE

    Al-Talabany, Shaween; Mordi, Ify; Graeme Houston, J.; Colhoun, Helen M.; Weir-McCall, Jonathan R.; Matthew, Shona Z.; Looker, Helen C.; Levin, Daniel; Belch, Jill J. F.; Dove, Fiona; Khan, Faisel; Lang, Chim C.

    2018-01-01

    Background: Epicardial adipose tissue (EAT) is an emerging cardio-metabolic risk factor and has been shown to correlate with adverse cardiovascular (CV) outcome; however the underlying pathophysiology of this link is not well understood. The aim of this study was to evaluate the relationship between EAT and a comprehensive panel of cardiovascular risk biomarkers and pulse wave velocity (PWV) and indexed left ventricular mass (LVMI) in a cohort of patients with cardiovascular disease (CVD) and...

  1. Cardiovascular fluid dynamics. Methods for flow and pressure field analysis from magnetic resonance imaging

    International Nuclear Information System (INIS)

    Ebbers, T.

    2001-01-01

    Cardiovascular blood flow is highly complex and incompletely understood. Blood flow patterns are expected to influence the opening and closing of normal and prosthetic heart valves, the efficiency of cardiac filling and ejection, and the resistance to thrombus formation within the heart. Conventional diagnostic techniques are poorly suited to the study of the three-dimensional (3D) blood flow patterns in the heart chambers and large vessels. Noninvasive methods have also been inadequate in studying intracardiac pressure differences, which are the driving force of flow and are critical in the evaluation of many cardiovascular abnormalities. This thesis focuses on the development of non-invasive methods for analysis of 3D cardiovascular blood flow. Simultaneous study of cardiovascular fluid dynamics allowed knowledge exchange across the two disciplines, facilitating the development process and broadening the applicability of the methods. A time-resolved 3D phase-contrast Magnetic Resonance Imaging (MRI) technique was used to acquire the velocity vector field in a 3D volume encompassing the entire heart or a large vessel. Cardiovascular blood flow patterns were visualized by use of particle traces, which revealed, for instance, vortical flow patterns in the left atrium. By applying the Navier-Stokes equation along a user-defined line in the 3D velocity vector field, the relative pressure could be obtained as an excellent supplement to the flow pattern visualization. Using a delineation of the blood pool, the time-varying 3D relative pressure field in the human left ventricle was obtained from the velocity field by use of the pressure Poisson equation. A delineation of the heart muscle, a task that is almost impossible to perform on 3D MRI either automatically or manually, was also achieved by usage of particle traces. This segmentation allows automatic calculation of the 3D relative pressure field, as well as calculation of well-established parameters such as

  2. Automatic recognition of fundamental tissues on histology images of the human cardiovascular system.

    Science.gov (United States)

    Mazo, Claudia; Trujillo, Maria; Alegre, Enrique; Salazar, Liliana

    2016-10-01

    Cardiovascular disease is the leading cause of death worldwide. Therefore, techniques for improving diagnosis and treatment in this field have become key areas for research. In particular, approaches for tissue image processing may support education system and medical practice. In this paper, an approach to automatic recognition and classification of fundamental tissues, using morphological information is presented. Taking a 40× or 10× histological image as input, three clusters are created with the k-means algorithm using a structural tensor and the red and the green channels. Loose connective tissue, light regions and cell nuclei are recognised on 40× images. Then, the cell nuclei's features - shape and spatial projection - and light regions are used to recognise and classify epithelial cells and tissue into flat, cubic and cylindrical. In a similar way, light regions, loose connective and muscle tissues are recognised on 10× images. Finally, the tissue's function and composition are used to refine muscle tissue recognition. Experimental validation is then carried out by histologist following expert criteria, along with manually annotated images that are used as a ground-truth. The results revealed that the proposed approach classified the fundamental tissues in a similar way to the conventional method employed by histologists. The proposed automatic recognition approach provides for epithelial tissues a sensitivity of 0.79 for cubic, 0.85 for cylindrical and 0.91 for flat. Furthermore, the experts gave our method an average score of 4.85 out of 5 in the recognition of loose connective tissue and 4.82 out of 5 for muscle tissue recognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Echocardiographic epicardial adipose tissue measurements provide information about cardiovascular risk in hemodialysis patients.

    Science.gov (United States)

    Ulusal Okyay, Gülay; Okyay, Kaan; Polattaş Solak, Evşen; Sahinarslan, Asife; Paşaoğlu, Özge; Ayerden Ebinç, Fatma; Paşaoğlu, Hatice; Boztepe Derici, Ülver; Sindel, Şükrü; Arınsoy, Turgay

    2015-07-01

    Epicardial adipose tissue (EAT) is a cardiovascular risk predictor in general population. However, its value has not been well validated in maintainance hemodialysis (MHD) patients. We aimed to assess associations of EAT with cardiovascular risk predictors in nondiabetic MHD patients. In this cross-sectional study, we measured EAT thickness by transthoracic echocardiography in 50 MHD patients (45.8 ± 14.6 years of age, 37 male). Antropometric measurements, bioimpedance analysis, left ventricular (LV) mass, carotis intima media thickness, blood tests, homeostasis model assessment for insulin resistance (HOMA-IR) and hemodialysis dose by single-pool urea clearence index (spKt/V) were determined. The mean EAT thickness was 3.28 ± 1.04 mm. There were significant associations of EAT with body mass index (β = 0.590, P  0.05). Body mass index, waist circumference, body fat mass, percentage of lean tissue mass, LV mass, triglyceride/high-density lipoprotein cholesterol ratio, HOMA-IR, and spKt/V appeared as independent predictors of EAT. EAT was significantly associated with body fat measures, cardiovascular risk predictors, and dialysis dose in MHD patients. © 2015 International Society for Hemodialysis.

  4. Classification of cardiovascular tissues using LBP based descriptors and a cascade SVM.

    Science.gov (United States)

    Mazo, Claudia; Alegre, Enrique; Trujillo, Maria

    2017-08-01

    Histological images have characteristics, such as texture, shape, colour and spatial structure, that permit the differentiation of each fundamental tissue and organ. Texture is one of the most discriminative features. The automatic classification of tissues and organs based on histology images is an open problem, due to the lack of automatic solutions when treating tissues without pathologies. In this paper, we demonstrate that it is possible to automatically classify cardiovascular tissues using texture information and Support Vector Machines (SVM). Additionally, we realised that it is feasible to recognise several cardiovascular organs following the same process. The texture of histological images was described using Local Binary Patterns (LBP), LBP Rotation Invariant (LBPri), Haralick features and different concatenations between them, representing in this way its content. Using a SVM with linear kernel, we selected the more appropriate descriptor that, for this problem, was a concatenation of LBP and LBPri. Due to the small number of the images available, we could not follow an approach based on deep learning, but we selected the classifier who yielded the higher performance by comparing SVM with Random Forest and Linear Discriminant Analysis. Once SVM was selected as the classifier with a higher area under the curve that represents both higher recall and precision, we tuned it evaluating different kernels, finding that a linear SVM allowed us to accurately separate four classes of tissues: (i) cardiac muscle of the heart, (ii) smooth muscle of the muscular artery, (iii) loose connective tissue, and (iv) smooth muscle of the large vein and the elastic artery. The experimental validation was conducted using 3000 blocks of 100 × 100 sized pixels, with 600 blocks per class and the classification was assessed using a 10-fold cross-validation. using LBP as the descriptor, concatenated with LBPri and a SVM with linear kernel, the main four classes of tissues were

  5. Validation of cardiovascular magnetic resonance assessment of pericardial adipose tissue volume

    Directory of Open Access Journals (Sweden)

    Sanders Prashanthan

    2009-05-01

    Full Text Available Abstract Background Pericardial adipose tissue (PAT has been shown to be an independent predictor of coronary artery disease. To date its assessment has been restricted to the use of surrogate echocardiographic indices such as measurement of epicardial fat thickness over the right ventricular free wall, which have limitations. Cardiovascular magnetic resonance (CMR offers the potential to non-invasively assess total PAT, however like other imaging modalities, CMR has not yet been validated for this purpose. Thus, we sought to describe a novel technique for assessing total PAT with validation in an ovine model. Methods 11 merino sheep were studied. A standard clinical series of ventricular short axis CMR images (1.5T Siemens Sonata were obtained during mechanical ventilation breath-holds. Beginning at the mitral annulus, consecutive end-diastolic ventricular images were used to determine the area and volume of epicardial, paracardial and pericardial adipose tissue. In addition adipose thickness was measured at the right ventricular free wall. Following euthanasia, the paracardial adipose tissue was removed from the ventricle and weighed to allow comparison with corresponding CMR measurements. Results There was a strong correlation between CMR-derived paracardial adipose tissue volume and ex vivo paracardial mass (R2 = 0.89, p ex vivo paracardial mass (R2 = 0.003, p = 0.878. Conclusion In this ovine model, CMR-derived paracardial adipose tissue volume, but not the corresponding and conventional measure of paracardial adipose thickness over the RV free wall, accurately reflected paracardial adipose tissue mass. This study validates for the first time, the use of clinically utilised CMR sequences for the accurate and reproducible assessment of pericardial adiposity. Furthermore this non-invasive modality does not use ionising radiation and therefore is ideally suited for future studies of PAT and its role in cardiovascular risk prediction and

  6. Evidence Report: Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure

    Science.gov (United States)

    Patel, Zarana; Huff, Janice; Saha, Janapriya; Wang, Minli; Blattnig, Steve; Wu, Honglu; Cucinotta, Francis

    2015-01-01

    Occupational radiation exposure from the space environment may result in non-cancer or non-CNS degenerative tissue diseases, such as cardiovascular disease, cataracts, and respiratory or digestive diseases. However, the magnitude of influence and mechanisms of action of radiation leading to these diseases are not well characterized. Radiation and synergistic effects of radiation cause DNA damage, persistent oxidative stress, chronic inflammation, and accelerated tissue aging and degeneration, which may lead to acute or chronic disease of susceptible organ tissues. In particular, cardiovascular pathologies such as atherosclerosis are of major concern following gamma-ray exposure. This provides evidence for possible degenerative tissue effects following exposures to ionizing radiation in the form of the GCR or SPEs expected during long-duration spaceflight. However, the existence of low dose thresholds and dose-rate and radiation quality effects, as well as mechanisms and major risk pathways, are not well-characterized. Degenerative disease risks are difficult to assess because multiple factors, including radiation, are believed to play a role in the etiology of the diseases. As additional evidence is pointing to lower, space-relevant thresholds for these degenerative effects, particularly for cardiovascular disease, additional research with cell and animal studies is required to quantify the magnitude of this risk, understand mechanisms, and determine if additional protection strategies are required.The NASA PEL (Permissive Exposure Limit)s for cataract and cardiovascular risks are based on existing human epidemiology data. Although animal and clinical astronaut data show a significant increase in cataracts following exposure and a reassessment of atomic bomb (A-bomb) data suggests an increase in cardiovascular disease from radiation exposure, additional research is required to fully understand and quantify these adverse outcomes at lower doses (less than 0.5 gray

  7. Resistin increases islet blood flow and decreases subcutaneous adipose tissue blood flow in anaesthetized rats.

    Science.gov (United States)

    Danielsson, T; Fredriksson, L; Jansson, L; Henriksnäs, J

    2009-02-01

    Resistin is an adipokine which has been suggested to participate in the induction of insulin resistance associated with type 2 diabetes. The aim of the present study was to investigate whether acute administration of resistin influences tissue blood perfusion in rats. Resistin was administered as an intravenous infusion of 7.5 microg h(-1) (1.5 mL h(-1)) for 30 min to rats anaesthetized with thiobutabarbital. A microsphere technique was used to estimate the blood flow to six different depots of white adipose tissue (WAT), brown adipose tissue (BAT), as well as to the pancreas, islets, duodenum, colon, kidneys, adrenal glands and liver. Resistin administration led to an increased blood flow to the pancreas and islets and a decrease in subcutaneous WAT and BAT. Intra-abdominal white adipose tissue blood flow and that to other organs were not affected. Acute administration of resistin markedly affects the blood perfusion of both the pancreas and subcutaneous white adipose tissue depots. At present it is unknown whether resistin exerts a direct effect on the vasculature, or works through local or systemic activation of endothelial cells and/or macrophages. The extent to which this might contribute to the insulin resistance caused by resistin is yet unknown.

  8. Sympathetic reflex control of blood flow in human peripheral tissues

    DEFF Research Database (Denmark)

    Henriksen, O

    1991-01-01

    sympathetic vasoconstrictor reflexes are blocked. Blood flow has been measure by the local 133Xe-technique. The results indicate the presence of spinal as well as supraspinal sympathetic vasoconstrictor reflexes to human peripheral tissues. Especially is emphasized the presence of a local sympathetic veno......Sympathetic vasoconstrictor reflexes are essential for the maintenance of arterial blood pressure in upright position. It has been generally believed that supraspinal sympathetic vasoconstrictor reflexes elicited by changes in baroreceptor activity play an important role. Recent studies on human...... skeletal muscle, cutaneous and subcutaneous tissues of the limbs indicate that the situation is more complex. Measurements have been carried out during acute as well as chronic sympathetic denervation. Spinal sympathetic reflex mechanisms have been evaluated in tetraplegic patients, where supraspinal...

  9. Bacterial adherence to graft tissues in static and flow conditions.

    Science.gov (United States)

    Veloso, Tiago Rafael; Claes, Jorien; Van Kerckhoven, Soetkin; Ditkowski, Bartosz; Hurtado-Aguilar, Luis G; Jockenhoevel, Stefan; Mela, Petra; Jashari, Ramadan; Gewillig, Marc; Hoylaerts, Marc F; Meyns, Bart; Heying, Ruth

    2018-01-01

    Various conduits and stent-mounted valves are used as pulmonary valve graft tissues for right ventricular outflow tract reconstruction with good hemodynamic results. Valve replacement carries an increased risk of infective endocarditis (IE). Recent observations have increased awareness of the risk of IE after transcatheter implantation of a stent-mounted bovine jugular vein valve. This study focused on the susceptibility of graft tissue surfaces to bacterial adherence as a potential risk factor for subsequent IE. Adhesion of Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus sanguinis to bovine pericardium (BP) patch, bovine jugular vein (BJV), and cryopreserved homograft (CH) tissues was quantified under static and shear stress conditions. Microscopic analysis and histology were performed to evaluate bacterial adhesion to matrix components. In general, similar bacteria numbers were recovered from CH and BJV tissue surfaces for all strains, especially in flow conditions. Static bacterial adhesion to the CH wall was lower for S sanguinis adhesion (P static conditions (P forces per se are not the prime determinants of bacterial adherence. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  10. Sympathetic reflex control of blood flow in human peripheral tissues

    DEFF Research Database (Denmark)

    Henriksen, O

    1991-01-01

    sympathetic vasoconstrictor reflexes are blocked. Blood flow has been measure by the local 133Xe-technique. The results indicate the presence of spinal as well as supraspinal sympathetic vasoconstrictor reflexes to human peripheral tissues. Especially is emphasized the presence of a local sympathetic veno......Sympathetic vasoconstrictor reflexes are essential for the maintenance of arterial blood pressure in upright position. It has been generally believed that supraspinal sympathetic vasoconstrictor reflexes elicited by changes in baroreceptor activity play an important role. Recent studies on human...

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

    Science.gov (United States)

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

    2015-06-01

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

  12. Utility of Tissue Inhibitor Metalloproteinase-1 and Osteopontin as Prospective Biomarkers of Early Cardiovascular Complications in Type 2 Diabetes.

    Science.gov (United States)

    El-Din, Doaa Samir Salah; Amin, Ahmed Ibrahim; Egiza, Ahmed Osman

    2018-02-15

    This work investigated associations between tissue inhibitor metalloproteinase-1 and diabetic cardiovascular diseases in type 2 diabetic patients; also it investigated the role of osteopontin in the diagnosis of type 2 cardiovascular diabetes complications. These were examined on eighty subjects, divided into three groups as follows: twenty volunteer healthy control subjects, thirty type 2 diabetes mellitus (DM) patients, and thirty cardiovascular, diabetic patients. Full clinical measurements were carried out, and the expression level of tissue inhibitor metalloproteinase-1 in blood samples was analysed by real-time PCR, using gene-specific primer pairs. Also osteopontin concentrations had been measured by the enzyme-linked immunosorbent assay. Data were tested statistically by parametric tests. The concentrations of osteopontin and the expression levels of tissue inhibitor metalloproteinase-1 were significantly increased in diabetic and cardiovascular diabetic groups compared to control group also they were significantly increased in the cardiovascular diabetic group compared to the diabetic group. Tissue inhibitor metalloproteinase-1 and osteopontin concentrations were significantly increased in diabetic patients with cardiovascular complications than other groups.

  13. Remifentanil decreases oral tissue blood flow while maintaining internal carotid artery blood flow during sevoflurane anesthesia in rabbits.

    Science.gov (United States)

    Hirata, Atsushi; Kasahara, Masataka; Matsuura, Nobuyuki; Ichinohe, Tatsuya

    2018-03-02

    The aim of this study was to investigate the effect of remifentanil infusion on oral tissue blood flow including submandibular gland tissue blood flow (SBF) and internal carotid artery blood flow (ICBF) in rabbits during sevoflurane anesthesia. Twelve male Japan White rabbits were anesthetized with sevoflurane and remifentanil. Remifentanil was infused at 0.2 and 0.4 µg/kg/min. Measurements included circulatory variables, common and external carotid artery blood flow (CCBF, ECBF), ICBF, tongue mucosal blood flow (TMBF), masseter muscle tissue blood flow (MBF), mandibular bone marrow tissue blood flow (BBF), tongue muscle tissue blood flow (TBF) and SBF. Vascular resistances for each tissue, including the tongue mucosa, masseter muscle, mandibular bone marrow, tongue muscle and submandibular gland, were calculated by dividing the mean arterial pressure by the respective tissue blood flow. Remifentanil infusion decreased oral tissue blood flow and circulatory variables. CCBF, ECBF and ICBF did not change. The calculated vascular resistance in each oral tissue, except for the tongue mucosa, increased in an infusion-rate-dependent manner. These results showed that remifentanil infusion reduced TMBF, MBF, BBF, TBF and SBF in an infusion-rate-dependent manner without affecting ICBF under sevoflurane anesthesia.

  14. Heating in vascular tissue and flow-through tissue phantoms induced by focused ultrasound

    Science.gov (United States)

    Huang, Jinlan

    High intensity focused ultrasound (HIFU) can be used to control bleeding, both from individual blood vessels as well as from gross damage to the capillary bed. This process, called acoustic hemostasis, is being studied in the hope that such a method would ultimately provide a lifesaving treatment during the so-called "golden hour", a brief grace period after a severe trauma in which prompt therapy can save the life of an injured person. Thermal effects play a major role in occlusion of small vessels and also appear to contribute to the sealing of punctures in major blood vessels. However, aggressive ultrasound-induced tissue heating can also impact healthy tissue and can lead to deleterious mechanical bioeffects. Moreover, the presence of vascularity can limit one's ability to elevate the temperature of blood vessel walls owing to convective heat transport. In an effort to better understand the heating process in tissues with vascular structure we have developed a numerical simulation that couples models for ultrasound propagation, acoustic streaming, ultrasound heating and blood cooling in Newtonian viscous media. The 3-D simulation allows for the study of complicated biological structures and insonation geometries. We have also undertaken a series of in vitro experiments, in non-uniform flow-through tissue phantoms, designed to provide a ground truth verification of the model predictions. The calculated and measured results were compared over a range of values for insonation pressure, insonation time, and flow rate; we show good agreement between predictions and measurements. We then conducted a series of simulations that address two limiting problems of interest: hemostasis in small and large vessels. We employed realistic human tissue properties and considered more complex geometries. Results show that the heating pattern in and around a blood vessel is different for different vessel sizes, flow rates and for varying beam orientations relative to the flow axis

  15. Impact of intermittent apnea on myocardial tissue oxygenation--a study using oxygenation-sensitive cardiovascular magnetic resonance.

    Directory of Open Access Journals (Sweden)

    Dominik P Guensch

    Full Text Available BACKGROUND: Carbon dioxide (CO(2 is a recognized vasodilator of myocardial blood vessels that leads to changes in myocardial oxygenation through the recruitment of the coronary flow reserve. Yet, it is unknown whether changes of carbon dioxide induced by breathing maneuvers can be used to modify coronary blood flow and thus myocardial oxygenation. Oxygenation-sensitive cardiovascular magnetic resonance (CMR using the blood oxygen level-dependent (BOLD effect allows for non-invasive monitoring of changes of myocardial tissue oxygenation. We hypothesized that mild hypercapnia induced by long breath-holds leads to changes in myocardial oxygenation that can be detected by oxygenation-sensitive CMR. METHODS AND RESULTS: In nine anaesthetized and ventilated pigs, 60s breath-holds were induced. Left ventricular myocardial and blood pool oxygenation changes, as monitored by oxygenation-sensitive CMR using a T2*-weighted steady-state-free-precession (SSFP sequence at 1.5T, were compared to changes of blood gas levels obtained immediately prior to and after the breath-hold. Long breath-holds resulted in an increase of paCO(2, accompanied by a decrease of paO(2 and pH. There was a significant decrease of blood pressure, while heart rate did not change. A decrease in the left ventricular blood pool oxygenation was observed, which was similar to drop in SaO(2. Oxygenation in the myocardial tissue however, was maintained throughout the period. Changes in myocardial oxygenation were strongly correlated with the change in paCO(2 during the breath-hold (r = 0.90, p = 0.010. CONCLUSION: Despite a drop in blood oxygen levels, myocardial oxygenation is maintained throughout long breath-holds and is linearly correlated with the parallel increase of arterial CO(2, a known coronary vasodilator. Breathing maneuvers in combination with oxygenation-sensitive CMR may be useful as a diagnostic test for coronary artery function.

  16. Promising Therapeutic Strategies for Mesenchymal Stem Cell-Based Cardiovascular Regeneration: From Cell Priming to Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Seung Taek Ji

    2017-01-01

    Full Text Available The primary cause of death among chronic diseases worldwide is ischemic cardiovascular diseases, such as stroke and myocardial infarction. Recent evidence indicates that adult stem cell therapies involving cardiovascular regeneration represent promising strategies to treat cardiovascular diseases. Owing to their immunomodulatory properties and vascular repair capabilities, mesenchymal stem cells (MSCs are strong candidate therapeutic stem cells for use in cardiovascular regeneration. However, major limitations must be overcome, including their very low survival rate in ischemic lesion. Various attempts have been made to improve the poor survival and longevity of engrafted MSCs. In order to develop novel therapeutic strategies, it is necessary to first identify stem cell modulators for intracellular signal triggering or niche activation. One promising therapeutic strategy is the priming of therapeutic MSCs with stem cell modulators before transplantation. Another is a tissue engineering-based therapeutic strategy involving a cell scaffold, a cell-protein-scaffold architecture made of biomaterials such as ECM or hydrogel, and cell patch- and 3D printing-based tissue engineering. This review focuses on the current clinical applications of MSCs for treating cardiovascular diseases and highlights several therapeutic strategies for promoting the therapeutic efficacy of MSCs in vitro or in vivo from cell priming to tissue engineering strategies, for use in cardiovascular regeneration.

  17. A Pulsatile Bioreactor for Conditioning of Tissue-Engineered Cardiovascular Constructs under Endoscopic Visualization

    Directory of Open Access Journals (Sweden)

    Bassil Akra

    2012-07-01

    Full Text Available Heart valve disease (HVD is a globally increasing problem and accounts for thousands of deaths yearly. Currently end-stage HVD can only be treated by total valve replacement, however with major drawbacks. To overcome the limitations of conventional substitutes, a new clinical approach based on cell colonization of artificially manufactured heart valves has been developed. Even though this attempt seems promising, a confluent and stable cell layer has not yet been achieved due to the high stresses present in this area of the human heart. This study describes a bioreactor with a new approach to cell conditioning of tissue engineered heart valves. The bioreactor provides a low pulsatile flow that grants the correct opening and closing of the valve without high shear stresses. The flow rate can be regulated allowing a steady and sensitive conditioning process. Furthermore, the correct functioning of the valve can be monitored by endoscope surveillance in real-time. The tubeless and modular design allows an accurate, simple and faultless assembly of the reactor in a laminar flow chamber. It can be concluded that the bioreactor provides a strong tool for dynamic pre-conditioning and monitoring of colonized heart valve prostheses physiologically exposed to shear stress.

  18. Multidirectional flow analysis by cardiovascular magnetic resonance in aneurysm development following repair of aortic coarctation

    Directory of Open Access Journals (Sweden)

    Stalder Aurelien F

    2008-06-01

    Full Text Available Abstract Aneurysm formation is a life-threatening complication after operative therapy in coarctation. The identification of patients at risk for the development of such secondary pathologies is of high interest and requires a detailed understanding of the link between vascular malformation and altered hemodynamics. The routine morphometric follow-up by magnetic resonance angiography is a well-established technique. However, the intrinsic sensitivity of magnetic resonance (MR towards motion offers the possibility to additionally investigate hemodynamic consequences of morphological changes of the aorta. We demonstrate two cases of aneurysm formation 13 and 35 years after coarctation surgery based on a Waldhausen repair with a subclavian patch and a Vosschulte repair with a Dacron patch, respectively. Comprehensive flow visualization by cardiovascular MR (CMR was performed using a flow-sensitive, 3-dimensional, and 3-directional time-resolved gradient echo sequence at 3T. Subsequent analysis included the calculation of a phase contrast MR angiography and color-coded streamline and particle trace 3D visualization. Additional quantitative evaluation provided regional physiological information on blood flow and derived vessel wall parameters such as wall shear stress and oscillatory shear index. The results highlight the individual 3D blood-flow patterns associated with the different vascular pathologies following repair of aortic coarctation. In addition to known factors predisposing for aneurysm formation after surgical repair of coarctation these findings indicate the importance of flow sensitive CMR to follow up hemodynamic changes with respect to the development of vascular disease.

  19. Cardiac extracellular matrix-fibrin hybrid scaffolds with tunable properties for cardiovascular tissue engineering.

    Science.gov (United States)

    Williams, Corin; Budina, Erica; Stoppel, Whitney L; Sullivan, Kelly E; Emani, Sirisha; Emani, Sitaram M; Black, Lauren D

    2015-03-01

    Solubilized cardiac extracellular matrix (ECM) is being developed as an injectable therapeutic that offers promise for promoting cardiac repair. However, the ECM alone forms a hydrogel that is very soft compared to the native myocardium. As both the stiffness and composition of the ECM are important in regulating cell behavior and can have complex synergistic effects, we sought to develop an ECM-based scaffold with tunable biochemical and mechanical properties. We used solubilized rat cardiac ECM from two developmental stages (neonatal, adult) combined with fibrin hydrogels that were cross-linked with transglutaminase. We show that ECM was retained within the gels and that the Young's modulus could be tuned to span the range of the developing and mature heart. C-kit+ cardiovascular progenitor cells from pediatric patients with congenital heart defects were seeded into the hybrid gels. Both the elastic modulus and composition of the scaffolds impacted the expression of endothelial and smooth muscle cell genes. Furthermore, we demonstrate that the hybrid gels are injectable, and thus have potential for minimally invasive therapies. ECM-fibrin hybrid scaffolds offer new opportunities for exploiting the effects of both composition and mechanical properties in directing cell behavior for tissue engineering. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  20. L-Arginine metabolism in cardiovascular and renal tissue from hyper- and hypothyroid rats.

    Science.gov (United States)

    Rodríguez-Gómez, Isabel; Moliz, Juan N; Quesada, Andrés; Montoro-Molina, Sebastian; Vargas-Tendero, Pablo; Osuna, Antonio; Wangensteen, Rosemary; Vargas, Félix

    2016-03-01

    This study assessed the effects of thyroid hormones on the enzymes involved in l-arginine metabolism and the metabolites generated by the different metabolic pathways. Compounds of l-arginine metabolism were measured in the kidney, heart, aorta, and liver of euthyroid, hyperthyroid, and hypothyroid rats after 6 weeks of treatment. Enzymes studied were NOS isoforms (neuronal [nNOS], inducible [iNOS], and endothelial [eNOS]), arginases I and II, ornithine decarboxylase (ODC), ornithine aminotransferase (OAT), and l-arginine decarboxylase (ADC). Metabolites studied were l-arginine, l-citrulline, spermidine, spermine, and l-proline. Kidney heart and aorta levels of eNOS and iNOS were augmented and reduced (P l-arginine, was reduced (P l-arginine metabolic pathways. The changes recorded in the abundance of eNOS, arginases I and II, and ADC protein in renal and cardiovascular tissues may play a role in the hemodynamic and renal manifestations observed in thyroid disorders. Furthermore, the changes in ODC and spermidine might contribute to the changes in cardiac and renal mass observed in thyroid disorders. © 2015 by the Society for Experimental Biology and Medicine.

  1. Cardiovascular risk factors cause premature rarefaction of the collateral circulation and greater ischemic tissue injury.

    Science.gov (United States)

    Moore, Scott M; Zhang, Hua; Maeda, Nobuyo; Doerschuk, Claire M; Faber, James E

    2015-07-01

    Collaterals lessen tissue injury in occlusive disease. However, aging causes progressive decline in their number and smaller diameters in those that remain (collateral rarefaction), beginning at 16 months of age in mice (i.e., middle age), and worse ischemic injury-effects that are accelerated in even 3-month-old eNOS(-/-) mice. These findings have found indirect support in recent human studies. We sought to determine whether other cardiovascular risk factors (CVRFs) associated with endothelial dysfunction cause collateral rarefaction, investigate possible mechanisms, and test strategies for prevention. Mice with nine different models of CVRFs of 4-12 months of age were assessed for number and diameter of native collaterals in skeletal muscle and brain and for collateral-dependent perfusion and ischemic injury after arterial occlusion. Hypertension caused collateral rarefaction whose severity increased with duration and level of hypertension, accompanied by greater hindlimb ischemia and cerebral infarct volume. Chronic treatment of wild-type mice with L-N (G)-nitro-arginine methylester caused similar rarefaction and worse ischemic injury which were not prevented by lowering arterial pressure with hydralazine. Metabolic syndrome, hypercholesterolemia, diabetes mellitus, and obesity also caused collateral rarefaction. Neither chronic statin treatment nor exercise training lessened hypertension-induced rarefaction. Chronic CVRF presence caused collateral rarefaction and worse ischemic injury, even at relatively young ages. Rarefaction was associated with increased proliferation rate of collateral endothelial cells, effects that may promote accelerated endothelial cell senescence.

  2. Differential flow improvements after valve replacements in bicuspid aortic valve disease: a cardiovascular magnetic resonance assessment.

    Science.gov (United States)

    Bissell, Malenka M; Loudon, Margaret; Hess, Aaron T; Stoll, Victoria; Orchard, Elizabeth; Neubauer, Stefan; Myerson, Saul G

    2018-02-08

    Abnormal aortic flow patterns in bicuspid aortic valve disease (BAV) may be partly responsible for the associated aortic dilation. Aortic valve replacement (AVR) may normalize flow patterns and potentially slow the concomitant aortic dilation. We therefore sought to examine differences in flow patterns post AVR. Ninety participants underwent 4D flow cardiovascular magnetic resonance: 30 BAV patients with prior AVR (11 mechanical, 10 bioprosthetic, 9 Ross procedure), 30 BAV patients with a native aortic valve and 30 healthy subjects. The majority of subjects with mechanical AVR or Ross showed normal flow pattern (73% and 67% respectively) with near normal rotational flow values (7.2 ± 3.9 and 10.6 ± 10.5 mm 2 /ms respectively vs 3.8 ± 3.1 mm 2 /s for healthy subjects; both p > 0.05); and reduced in-plane wall shear stress (0.19 ± 0.13 N/m 2 for mechanical AVR vs. 0.40 ± 0.28 N/m 2 for native BAV, p flow patterns (mainly marked right-handed helical flow), with comparable rotational flow values to native BAV (20.7 ± 8.8 mm 2 /ms and 26.6 ± 16.6 mm 2 /ms respectively, p > 0.05), and a similar pattern for wall shear stress. Data before and after AVR (n = 16) supported these findings: mechanical AVR showed a significant reduction in rotational flow (30.4 ± 16.3 → 7.3 ± 4.1 mm 2 /ms; p flow patterns in BAV disease tend to normalize after mechanical AVR or Ross procedure, in contrast to the remnant abnormal flow pattern after bioprosthetic AVR. This may in part explain different aortic growth rates post AVR in BAV observed in the literature, but requires confirmation in a prospective study.

  3. Finite element modeling of mass transport in high-Péclet cardiovascular flows

    Science.gov (United States)

    Hansen, Kirk; Arzani, Amirhossein; Shadden, Shawn

    2016-11-01

    Mass transport plays an important role in many important cardiovascular processes, including thrombus formation and atherosclerosis. These mass transport problems are characterized by Péclet numbers of up to 108, leading to several numerical difficulties. The presence of thin near-wall concentration boundary layers requires very fine mesh resolution in these regions, while large concentration gradients within the flow cause numerical stabilization issues. In this work, we will discuss some guidelines for solving mass transport problems in cardiovascular flows using a stabilized Galerkin finite element method. First, we perform mesh convergence studies in a series of idealized and patient-specific geometries to determine the required near-wall mesh resolution for these types of problems, using both first- and second-order tetrahedral finite elements. Second, we investigate the use of several boundary condition types at outflow boundaries where backflow during some parts of the cardiac cycle can lead to convergence issues. Finally, we evaluate the effect of reducing Péclet number by increasing mass diffusivity as has been proposed by some researchers. This work was supported by the NSF GRFP and NSF Career Award #1354541.

  4. Diet-induced changes in subcutaneous adipose tissue blood flow in man

    DEFF Research Database (Denmark)

    Simonsen, L; Bülow, J; Astrup, A

    1990-01-01

    The effect of a carbohydrate-rich meal on subcutaneous adipose tissue blood flow was studied with and without continuous i.v. infusion of propranolol in healthy volunteers. The subcutaneous adipose tissue blood flow was measured with the 133Xe washout method in three different locations: the fore...

  5. Blood flow in healed and inflamed periodontal tissues of dogs

    Energy Technology Data Exchange (ETDEWEB)

    Hock, J.M.; Kim, S.

    1987-01-01

    The objectives of this study were to determine if increased blood flow associated with gingivitis would decrease following resolution of gingival inflammation in dogs with periodontitis; if increased blood flow in inflamed gingiva was associated with changes in the blood flow of alveolar bone, and if blood flow in gingiva and alveolar bone increased if periodontitis was reactivated by ligating teeth. Regional blood flow was measured in dogs with pre-existing periodontitis, using radioisotope-labelled, plastic microspheres. In the first experiment on 4 adult Beagle dogs, teeth in the left jaws were treated to resolve the periodontitis, while teeth in the right jaws were not treated. Gingival and bone blood flow were measured after 12 wk. Blood flow was significantly (p<0.05) lower in non-inflamed healed gingiva (32.1 +- 2.7 ml/min/100 g) than in inflamed gingiva (46.1 +- 5.3 ml/min/100 g). No differences in the blood flow of the alveolar bone underlying inflamed or non-inflamed gingiva were present. In the second experiment, the right mandibular teeth of 5 dogs were treated to resolve periodontitis while teeth in the other quadrants were ligated for 4, 10 or 12 wk. The duration of ligation did not alter blood flow. Gingival blood flow around ligated maxillary and mandibular teeth was comparable and approximately 54% higher than around non-ligated teeth (p<0.03). The difference in blood flow between gingiva with G.I.>1 and gingiva with G.I.<2 was significant (p<0.04). Blood flow in bone was not altered by changes in the inflammatory status of the overlying gingiva. The findings suggest that changes in blood flow associated with inflammation are reversible and that blood flow alveolar bone is regulated independently of gingival blood flow.

  6. Blood flow in healed and inflamed periodontal tissues of dogs

    International Nuclear Information System (INIS)

    Hock, J.M.; Kim, S.

    1987-01-01

    The objectives of this study were to determine if increased blood flow associated with gingivitis would decrease following resolution of gingival inflammation in dogs with periodontitis; if increased blood flow in inflamed gingiva was associated with changes in the blood flow of alveolar bone, and if blood flow in gingiva and alveolar bone increased if periodontitis was reactivated by ligating teeth. Regional blood flow was measured in dogs with pre-existing periodontitis, using radioisotope-labelled, plastic microspheres. In the first experiment on 4 adult Beagle dogs, teeth in the left jaws were treated to resolve the periodontitis, while teeth in the right jaws were not treated. Gingival and bone blood flow were measured after 12 wk. Blood flow was significantly (p 1 and gingiva with G.I.<2 was significant (p<0.04). Blood flow in bone was not altered by changes in the inflammatory status of the overlying gingiva. The findings suggest that changes in blood flow associated with inflammation are reversible and that blood flow alveolar bone is regulated independently of gingival blood flow. (author)

  7. Endothelium in cardiovascular tissue engineering: studies on exosomes, development, and recruitment

    NARCIS (Netherlands)

    Jong, O.G. de

    2016-01-01

    Cardiovascular disease is the leading cause of death worldwide. In the Netherlands over 17,000 surgical procedures related to cardiovascular disease are performed annually. About two-thirds of these surgeries are coronary artery bypass surgery procedures, and over 3000 surgeries are related to

  8. Prospective isolation of human embryonic stem cell-derived cardiovascular progenitors that integrate into human fetal heart tissue.

    Science.gov (United States)

    Ardehali, Reza; Ali, Shah R; Inlay, Matthew A; Abilez, Oscar J; Chen, Michael Q; Blauwkamp, Timothy A; Yazawa, Masayuki; Gong, Yongquan; Nusse, Roeland; Drukker, Micha; Weissman, Irving L

    2013-02-26

    A goal of regenerative medicine is to identify cardiovascular progenitors from human ES cells (hESCs) that can functionally integrate into the human heart. Previous studies to evaluate the developmental potential of candidate hESC-derived progenitors have delivered these cells into murine and porcine cardiac tissue, with inconclusive evidence regarding the capacity of these human cells to physiologically engraft in xenotransplantation assays. Further, the potential of hESC-derived cardiovascular lineage cells to functionally couple to human myocardium remains untested and unknown. Here, we have prospectively identified a population of hESC-derived ROR2(+)/CD13(+)/KDR(+)/PDGFRα(+) cells that give rise to cardiomyocytes, endothelial cells, and vascular smooth muscle cells in vitro at a clonal level. We observed rare clusters of ROR2(+) cells and diffuse expression of KDR and PDGFRα in first-trimester human fetal hearts. We then developed an in vivo transplantation model by transplanting second-trimester human fetal heart tissues s.c. into the ear pinna of a SCID mouse. ROR2(+)/CD13(+)/KDR(+)/PDGFRα(+) cells were delivered into these functioning fetal heart tissues: in contrast to traditional murine heart models for cell transplantation, we show structural and functional integration of hESC-derived cardiovascular progenitors into human heart.

  9. Bone tissue engineering: the role of interstitial fluid flow

    Science.gov (United States)

    Hillsley, M. V.; Frangos, J. A.

    1994-01-01

    It is well established that vascularization is required for effective bone healing. This implies that blood flow and interstitial fluid (ISF) flow are required for healing and maintenance of bone. The fact that changes in bone blood flow and ISF flow are associated with changes in bone remodeling and formation support this theory. ISF flow in bone results from transcortical pressure gradients produced by vascular and hydrostatic pressure, and mechanical loading. Conditions observed to alter flow rates include increases in venous pressure in hypertension, fluid shifts occurring in bedrest and microgravity, increases in vascularization during the injury-healing response, and mechanical compression and bending of bone during exercise. These conditions also induce changes in bone remodeling. Previously, we hypothesized that interstitial fluid flow in bone, and in particular fluid shear stress, serves to mediate signal transduction in mechanical loading- and injury-induced remodeling. In addition, we proposed that a lack or decrease of ISF flow results in the bone loss observed in disuse and microgravity. The purpose of this article is to review ISF flow in bone and its role in osteogenesis.

  10. Blood flow and oxygenation in peritendinous tissue and calf muscle during dynamic exercise in humans

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Langberg, H; Green, Sara Marie Ehrenreich

    2000-01-01

    1. Circulation around tendons may act as a shunt for muscle during exercise. The perfusion and oxygenation of Achilles' peritendinous tissue was measured in parallel with that of calf muscle during exercise to determine (1) whether blood flow is restricted in peritendinous tissue during exercise...... with a rise in leg vascular conductance and microvascular haemoglobin volume, despite elevated systemic vascular resistance. 4. The parallel rise in calf muscle and peritendinous blood flow and fall in O2 saturation during exercise indicate that blood flow is coupled to oxidative metabolism in both tissue......, and (2) whether blood flow is coupled to oxidative metabolism. 2. Seven individuals performed dynamic plantar flexion from 1 to 9 W. Radial artery and popliteal venous blood were sampled for O2, peritendinous blood flow was determined by 133Xe-washout, calf blood flow by plethysmography, cardiac output...

  11. Blood flow and oxygenation in peritendinous tissue and calf muscle during dynamic exercise in humans

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Langberg, H; Green, Sara Marie Ehrenreich

    2000-01-01

    1. Circulation around tendons may act as a shunt for muscle during exercise. The perfusion and oxygenation of Achilles' peritendinous tissue was measured in parallel with that of calf muscle during exercise to determine (1) whether blood flow is restricted in peritendinous tissue during exercise......, and (2) whether blood flow is coupled to oxidative metabolism. 2. Seven individuals performed dynamic plantar flexion from 1 to 9 W. Radial artery and popliteal venous blood were sampled for O2, peritendinous blood flow was determined by 133Xe-washout, calf blood flow by plethysmography, cardiac output...

  12. Exercise-induced increase in dog adipose tissue blood flow before and after denervation

    DEFF Research Database (Denmark)

    Bülow, J; Madsen, J

    1986-01-01

    Subcutaneous adipose tissue blood flow was examined during rest and exercise in the inguinal fat pads of four female dogs using the Xe wash-out technique. The experiments were performed before and after denervation of one of the pads. No difference between the resting flows in the two pads could...... be demonstrated either before or after denervation. The flow increased about two-fold on average from rest to exercise. This response was similar before and after denervation. It is concluded that direct sympathetic innervation is not involved in the regulation of adipose tissue blood flow during exercise....

  13. Calf blood flow at rest evaluated by thermal measurement with tissue temperature and heat flow and 133Xe clearance

    International Nuclear Information System (INIS)

    Tamura, Toshiyo; Togawa, Tatsuo; Fukuoka, Masakazu; Kawakami, Kenji.

    1982-01-01

    The regional blood flow in the calf was determined simultaneously by thermal measurement and by 133 Xe clearance technique. Calf blood flow (Ft) by thermal measurement was accounted for by the equation of the form Ft=(CdT*d+Ho-Mb)/rho sub(b)c su b(D) (Ta-Td), where Cd is thermal capacitance of the calf compartment, T*d is the change of calf tissue temperature, Ta is arterila blood temperature, Td is calf tissue temperature, Ho is the heat dissipation from the compartment to the environment, Mb is estimated metabolism of the calf tissue and rho sub(b)c sub(b) is the product of density and specific heat of blood. The healthy men were chosen for the experiments. Total calf blood flow was 2.53+-1.31ml/(min-100ml calf), and muscle blood flow was 2.63+-1.69ml/(min- 100ml muscle) and skin blood flow 7.19+-3.83ml/(min-100ml skin) measured by 133 Xe clearance. On the basis of the results, an estimate has been made of the proportions of the calf volume which can be ascribed to skin and muscle respectively. Estimated muscle and skin blood flow were correlated with total calf blood flow(r=0.98). (author)

  14. Tissue response to poly(L-lactic acid)-based blend with phospholipid polymer for biodegradable cardiovascular stents.

    Science.gov (United States)

    Kim, Hyung Il; Ishihara, Kazuhiko; Lee, Seungbok; Seo, Ji-Hun; Kim, Hye Young; Suh, Dongwhan; Kim, Min Uk; Konno, Tomohiro; Takai, Madoka; Seo, Jeong-Sun

    2011-03-01

    A temporary cardiovascular stent device by bioabsorbable materials might reduce late stent thrombosis. A water-soluble amphiphilic phospholipid polymer bearing phosphorylcholine groups (PMB30W) was blended with a high-molecular-weight poly(l-lactic acid) (PLLA) to reduce unfavorable tissue responses at the surface. The PLLA implants and the polymer blend (PLLA/PMB30W) implants were inserted into subcutaneous tissues of rats, the infrarenal aorta of rats, and the internal carotid arteries of rabbits. After 6 months subcutaneous implantation, the PLLA/PMB30W maintained high density of phosphorylcholine groups on the surface without a significant bioabsorption. After intravascular implantation, the cross-sectional areas of polymer tubing with diameters less than 1.6 mm were histomorphometrically measured. Compared to the PLLA tubing, the PLLA/PMB30W tubing significantly reduced the thrombus formation during 30 d of implantation. Human peripheral blood mononuclear cells were cultured on the PLLA and the PLLA/PMB30W to compare inflammatory reactions. Enzyme-linked immunosorbent assay quantified substantially decreased proinflammatory cytokines in the case of the PLLA/PMB30W. They were almost the same level as the negative controls. Thus, we conclude that the phosphorylcholine groups could reduce tissue responses significantly both in vivo and in vitro, and the PLLA/PMB30W is a promising material for preparing temporary cardiovascular stent devices. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Potential beneficial effect of some adipokines positively correlated with the adipose tissue content on the cardiovascular system.

    Science.gov (United States)

    Sawicka, Magdalena; Janowska, Joanna; Chudek, Jerzy

    2016-11-01

    Obesity is a risk factor of cardiovascular diseases. However, in the case of heart failure, obese and overweight patients have a more favourable prognosis compared to patients who have a normal body weight. This phenomenon is referred to as the "obesity paradox," and it is explained by, among others, a positive effect of adipokines produced by adipose tissue, particularly by the tissue located in the direct vicinity of the heart and blood vessels. The favourable effect on the cardiovascular system is mostly associated with adiponectin and omentin, but the levels of these substances are reduced in obese patients. Among the adipokines which levels are positively correlated with the adipose tissue content, favourable activity is demonstrated by apelin, progranulin, chemerin, TNF-α (tumour necrosis factor-)α, CTRP-3 (C1q/tumour necrosis factor (TNF) related protein), leptin, visfatin and vaspin. This activity is associated with the promotion of regeneration processes in the damaged myocardium, formation of new blood vessels, reduction of the afterload, improvement of metabolic processes in cardiomyocytes and myocardial contractile function, inhibition of apoptosis and fibrosis of the myocardium, as well as anti-inflammatory and anti-atheromatous effects. The potential use of these properties in the treatment of heart failure and ischaemic heart disease, as well as in pulmonary hypertension, arterial hypertension and the limitation of the loss of cardiomyocytes during cardioplegia-requiring cardiosurgical procedures, is studied. The most advanced studies focus on analogues of apelin and progranulin. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Flow-mediated dilation and cardiovascular event prediction: does nitric oxide matter?

    Science.gov (United States)

    Green, Daniel J; Jones, Helen; Thijssen, Dick; Cable, N T; Atkinson, Greg

    2011-03-01

    Endothelial dysfunction is an early atherosclerotic event that precedes clinical symptoms and may also render established plaque vulnerable to rupture. Noninvasive assessment of endothelial function is commonly undertaken using the flow-mediated dilation (FMD) technique. Some studies indicate that FMD possesses independent prognostic value to predict future cardiovascular events that may exceed that associated with traditional risk factor assessment. It has been assumed that this association is related to the proposal that FMD provides an index of endothelium-derived nitric oxide (NO) function. Interestingly, placement of the occlusion cuff during the FMD procedure alters the shear stress stimulus and NO dependency of the resulting dilation: cuff placement distal to the imaged artery leads to a largely NO-mediated response, whereas proximal cuff placement leads to dilation which is less NO dependent. We used this physiological observation and the knowledge that prognostic studies have used both approaches to examine whether the prognostic capacity of FMD is related to its role as a putative index of NO function. In a meta-analysis of 14 studies (>8300 subjects), we found that FMD derived using a proximal cuff was at least as predictive as that derived using distal cuff placement, despite the latter being more NO dependent. This suggests that, whilst FMD is strongly predictive of future cardiovascular events, this may not solely be related to its assumed NO dependency. Although this finding should be confirmed with more and larger studies, we suggest that any direct measure of vascular (endothelial) function may provide independent prognostic information in humans.

  17. Theoretical analysis of coronary blood flow and tissue oxygen pressure-control

    NARCIS (Netherlands)

    Spaan, J. A.; Dankelman, J.

    1993-01-01

    Coronary blood flow is tightly coupled to the myocardial oxygen consumption. We have presented a control model based on the assumption that the tissue oxygen pressure is the controlled variable. The coronary blood flow in itself is not a controlled variable but merely the result of a different

  18. Influence of oxidative stress on cardiovascular parameters in patients with combined flow of chronic obstructive pulmonary disease and arterial hypertension

    Directory of Open Access Journals (Sweden)

    V. G. Deinega

    2013-04-01

    Full Text Available Introduction. It is well known that active forms of oxygen, such as hydrogen peroxide, superoxide anion, hydroxyl radical and others are involved in different pathological conditions, such as cell necrosis, senescence, apoptosis, autophagy, inflammatory responses, remodeling of extracellular matrix and blood vessels, endothelial dysfunction, inactivation of antiproteases, and impaired tissue repair. The pathological increased production of mentioned active forms is called “oxidative stress”. From the literature data, we know that oxidative stress is involved in pathogenesis of arterial hypertension (AH, chronic obstructive pulmonary disease (COPD, atherosclerosis and others. The influence of oxidative stress on cardiovascular disorders in patients with combined flow of COPD and AH is not clearly known. Objective. To study peculiarities and links between parameters of oxidative stress and lesions of heart and vessels in patients with combined flow of COPD and AH. Materials and methods. A total of 101 patients with COPD, AH and with combined flow of COPD and AH were examined. The patients were divided into 3 groups. The first group was formed by patients with AH (n=29 the second group was formed by patients with COPD (n=29, the third group was formed by patients with combined flow of COPD and AH (n=57. Control group was formed from healthy persons of the same age and sex (n=22.All patients underwent spirography, echocardiography, ultrasound measurement of common carotid artery intimal-medial thickness and estimation of endhothelium-dependent vasodilatation. As oxidative stress markers, the levels of oxidative protein modification, spontaneous and iron induced aldehydephenylhydrazone’s (APH, ketondinitrophenylhydrazone’s (KPH and medium size molecules (MSM were measured. Results. Patients with combined flow of COPD and AH had higher levels of spontaneous APH (p<0,01 comparing with first and second group. The levels of spontaneous KPH were

  19. Correlation of Endostatin and Tissue Inhibitor of Metalloproteinases 2 (TIMP2 Serum Levels With Cardiovascular Involvement in Systemic Sclerosis Patients

    Directory of Open Access Journals (Sweden)

    Bozena Dziankowska-Bartkowiak

    2005-01-01

    pathogenesis of SSc. Heart fibrosis is one of the most important prognostic factors in SSc patients. So, the aim of our study was to examine cardiovascular dysfunction in SSc patients and its correlation with serum levels of vascular endothelial growth factor (VEGF, endostatin, and tissue inhibitor of metalloproteinase 2 (TIMP2. The study group comprised 34 patients (19 with limited scleroderma (lSSc and 15 with diffuse scleroderma (dSSc. The control group consisted of 20 healthy persons, age and sex matched. Internal organ involvement was assessed on the basis of specialist procedures. Serum VEGF, endostatin, and TIMP2 levels were evaluated by ELISA. We found cardiovascular changes in 15 patients with SSc (8 with lSSc and 7 with dSSc. The observed symptoms were of different characters and also coexisted with each other. Higher endostatin serum levels in all systemic sclerosis patients in comparison to the control group were demonstrated (P<.05. Also higher serum levels of endostatin and TIMP2 were observed in patients with cardiovascular changes in comparison to the patients without such changes (P<.05. The obtained results support the notion that angiogenesis and fibrosis disturbances may play an important role in SSc. Evaluation of endostatin and TIMP2 serum levels seems to be one of the noninvasive, helpful examinations of heart involvement in the course of systemic sclerosis.

  20. THE EFFECTS OF PHYSICAL TRAINING ON CARDIOVASCULAR PARAMETERS AND REDUCTION OF VISCERAL FATTY TISSUE

    Directory of Open Access Journals (Sweden)

    Todorka Savic

    2007-12-01

    Full Text Available Regular physical activity and good physical condition are widely accepted as factors that reduce all-cause mortality and improve a number of health outcomes.The aim of this study was to investigate the effects of aerobic exercise training on cardiovascular parameters and reduction of visceral obesity in patients with stable coronary artery disease participating in a cardiovascular rehabilitation exercise program. Fifty-two patients with stable coronary heart disease who had been accepted into the outpatient Phase II cardiovascular rehabilitation program at the Institute for Treatment and Rehabilitation of Cardiovascular Diseases Niska Banja, Nis, Serbia,were recruited for this study. All patients were divided into two groups: group with stable coronary heart disease who had regular aerobic physical training during 6weeks and control without physical training. There were not significant differences in body weight, body mass index, waist circumference and waist /hip ratio in start and at the end of physical training program. Physical training did not reduce the above mentioned parameters after 6 weeks. There were not significant differences in systolic and diastolic blood pressure at the beginning and at the end of the observed period.In group with physical training, a significant reduction of systolic and diastolic blood pressure after cardiovascular rehabilitation were reported (p<0.05. In patients with moderate aerobic physical training, a significant decrease in the heart rate was registered after the 6-week follow-up (p<0.05, while heart rate was significantly lower in this group compared to group with sedentary lifestyle (p<0.05. The effects of the 6-week cardiovascular rehabilitation on lipid parameters is visible only in slight reduction of triglyceride values in group with physical training (p<0.05. The concentration of triglycerides were significantly lower in this group compared to sedentary patients after the 6-week follow-up (p<0

  1. Carbon nanotubes reinforced chitosan films: mechanical properties and cell response of a novel biomaterial for cardiovascular tissue engineering.

    Science.gov (United States)

    Kroustalli, A; Zisimopoulou, A E; Koch, S; Rongen, L; Deligianni, D; Diamantouros, S; Athanassiou, G; Kokozidou, M; Mavrilas, D; Jockenhoevel, S

    2013-12-01

    Carbon nanotubes have been proposed as fillers to reinforce polymeric biomaterials for the strengthening of their structural integrity to achieve better biomechanical properties. In this study, a new polymeric composite material was introduced by incorporating various low concentrations of multiwalled carbon nanotubes (MWCNTs) into chitosan (CS), aiming at achieving a novel composite biomaterial with superior mechanical and biological properties compared to neat CS, in order to be used in cardiovascular tissue engineering applications. Both mechanical and biological characteristics in contact with the two relevant cell types (endothelial cells and vascular myofibroblasts) were studied. Regarding the mechanical behavior of MWCNT reinforced CS (MWCNT/CS), 5 and 10 % concentrations of MWCNTs enhanced the mechanical behavior of CS, with that of 5 % exhibiting a superior mechanical strength compared to 10 % concentration and neat CS. Regarding biological properties, MWCNT/CS best supported proliferation of endothelial and myofibroblast cells, MWCNTs and MWCNT/CS caused no apoptosis and were not toxic of the examined cell types. Conclusively, the new material could be suitable for tissue engineering (TE) and particularly for cardiovascular TE applications.

  2. Verification of a computational cardiovascular system model comparing the hemodynamics of a continuous flow to a synchronous valveless pulsatile flow left ventricular assist device

    Science.gov (United States)

    Gohean, Jeffrey R.; George, Mitchell J.; Pate, Thomas D.; Kurusz, Mark; Longoria, Raul G.; Smalling, Richard W.

    2012-01-01

    The purpose of this investigation is to utilize a computational model to compare a synchronized valveless pulsatile left ventricular assist device to continuous flow left ventricular assist devices at the same level of device flow, and to verify the model with in vivo porcine data. A dynamic system model of the human cardiovascular system was developed to simulate support of a healthy or failing native heart from a continuous flow left ventricular assist device or a synchronous, pulsatile, valveless, dual piston positive displacement pump. These results were compared to measurements made during in vivo porcine experiments. Results from the simulation model and from the in vivo counterpart show that the pulsatile pump provides higher cardiac output, left ventricular unloading, cardiac pulsatility, and aortic valve flow as compared to the continuous flow model at the same level of support. The dynamic system model developed for this investigation can effectively simulate human cardiovascular support by a synchronous pulsatile or continuous flow ventricular assist device. PMID:23438771

  3. Blood and interstitial flow in the hierarchical pore space architecture of bone tissue.

    Science.gov (United States)

    Cowin, Stephen C; Cardoso, Luis

    2015-03-18

    There are two main types of fluid in bone tissue, blood and interstitial fluid. The chemical composition of these fluids varies with time and location in bone. Blood arrives through the arterial system containing oxygen and other nutrients and the blood components depart via the venous system containing less oxygen and reduced nutrition. Within the bone, as within other tissues, substances pass from the blood through the arterial walls into the interstitial fluid. The movement of the interstitial fluid carries these substances to the cells within the bone and, at the same time, carries off the waste materials from the cells. Bone tissue would not live without these fluid movements. The development of a model for poroelastic materials with hierarchical pore space architecture for the description of blood flow and interstitial fluid flow in living bone tissue is reviewed. The model is applied to the problem of determining the exchange of pore fluid between the vascular porosity and the lacunar-canalicular porosity in bone tissue due to cyclic mechanical loading and blood pressure. These results are basic to the understanding of interstitial flow in bone tissue that, in turn, is basic to understanding of nutrient transport from the vasculature to the bone cells buried in the bone tissue and to the process of mechanotransduction by these cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Modeling microelectrode biosensors: free-flow calibration can substantially underestimate tissue concentrations.

    Science.gov (United States)

    Newton, Adam J H; Wall, Mark J; Richardson, Magnus J E

    2017-03-01

    Microelectrode amperometric biosensors are widely used to measure concentrations of analytes in solution and tissue including acetylcholine, adenosine, glucose, and glutamate. A great deal of experimental and modeling effort has been directed at quantifying the response of the biosensors themselves; however, the influence that the macroscopic tissue environment has on biosensor response has not been subjected to the same level of scrutiny. Here we identify an important issue in the way microelectrode biosensors are calibrated that is likely to have led to underestimations of analyte tissue concentrations. Concentration in tissue is typically determined by comparing the biosensor signal to that measured in free-flow calibration conditions. In a free-flow environment the concentration of the analyte at the outer surface of the biosensor can be considered constant. However, in tissue the analyte reaches the biosensor surface by diffusion through the extracellular space. Because the enzymes in the biosensor break down the analyte, a density gradient is set up resulting in a significantly lower concentration of analyte near the biosensor surface. This effect is compounded by the diminished volume fraction (porosity) and reduction in the diffusion coefficient due to obstructions (tortuosity) in tissue. We demonstrate this effect through modeling and experimentally verify our predictions in diffusive environments. NEW & NOTEWORTHY Microelectrode biosensors are typically calibrated in a free-flow environment where the concentrations at the biosensor surface are constant. However, when in tissue, the analyte reaches the biosensor via diffusion and so analyte breakdown by the biosensor results in a concentration gradient and consequently a lower concentration around the biosensor. This effect means that naive free-flow calibration will underestimate tissue concentration. We develop mathematical models to better quantify the discrepancy between the calibration and tissue

  5. Favorable Effects of Oxygen Inhalation in Patients After Bidirectional Glenn Procedure as Assessed by Cardiovascular Magnetic Resonance Flow Measurement.

    Science.gov (United States)

    Ishikawa, Yu-Ichi; Ishikawa, Shiro; Sagawa, Ko-Ichi; Ushinohama, Hiroya; Nakamura, Makoto; Kado, Hideaki

    2016-05-25

    Home oxygen therapy (HOT) is used to adapt patients to the bidirectional Glenn (BDG) physiology. However, the precise cardiovascular effect of oxygen inhalation is still unknown. We used phase-contrast MRI to evaluate the cardiovascular effects of oxygen inhalation in young patients with BDG physiology. The 56 sessions of cardiac MRI were performed in 36 patients with BDG circulation. Oxygen saturation (SpO2) and heart rate (HR) were monitored under both room air and nasal 100% oxygen inhalation, and the blood flow volumes of the ascending aorta (AA), superior vena cava (SVC), and inferior vena cava (IVC) were measured by phase-contrast MRI. Systemic-to-pulmonary collateral flow (SPCF) volumes were calculated by subtracting the sum of flow volumes through the SVC and IVC from the flow volume through the AA, and used for further comparative examination. Under nasal oxygen inhalation, SpO2significantly increased from 82% to 89%, while HR decreased from 115 to 110 beats/min. AA (5.0 vs. 4.9 L·min(-1)·m(-2)), SVC (1.85 vs. 1.77 L·min(-1)·m(-2)), and systemic blood flow volume (=SVC+IVC) significantly decreased (3.60 vs. 3.46 L·min(-1)·m(-2)). In contrast, SPCF and the pulmonary-to-systemic blood flow ratio (Qp/Qs) remained unchanged. Oxygen inhalation improved arterial blood oxygenation and lowered HR in patients with BDG circulation without an increase in Qp/Qs. HOT would be protective of the cardiovascular system in patients with BDG circulation. (Circ J 2016; 80: 1378-1385).

  6. Epicardial adipose tissue is related to arterial stiffness and inflammation in patients with cardiovascular disease and type 2 diabetes.

    Science.gov (United States)

    Al-Talabany, Shaween; Mordi, Ify; Graeme Houston, J; Colhoun, Helen M; Weir-McCall, Jonathan R; Matthew, Shona Z; Looker, Helen C; Levin, Daniel; Belch, Jill J F; Dove, Fiona; Khan, Faisel; Lang, Chim C

    2018-02-13

    Epicardial adipose tissue (EAT) is an emerging cardio-metabolic risk factor and has been shown to correlate with adverse cardiovascular (CV) outcome; however the underlying pathophysiology of this link is not well understood. The aim of this study was to evaluate the relationship between EAT and a comprehensive panel of cardiovascular risk biomarkers and pulse wave velocity (PWV) and indexed left ventricular mass (LVMI) in a cohort of patients with cardiovascular disease (CVD) and diabetes compared to controls. One hundred forty-five participants (mean age 63.9 ± 8.1 years; 61% male) were evaluated. All patients underwent cardiovascular magnetic resonance (CMR) examination and PWV. EAT measurements from CMR were performed on the 4-chamber view. Blood samples were taken and a range of CV biomarkers was evaluated. EAT measurements were significantly higher in the groups with CVD, with or without T2DM compared to patients without CVD or T2DM (group 1 EAT 15.9 ± 5.5 cm 2 vs. group 4 EAT 11.8 ± 4.1 cm 2 , p = 0.001; group 3 EAT 15.1 ± 4.3 cm 2 vs. group 4 EAT 11.8 ± 4.1 cm 2 , p = 0.024). EAT was independently associated with IL-6 (beta 0.2, p = 0.019). When added to clinical variables, both EAT (beta 0.16, p = 0.035) and IL-6 (beta 0.26, p = 0.003) were independently associated with PWV. EAT was significantly associated with LVMI in a univariable analysis but not when added to significant clinical variables. In patients with cardio-metabolic disease, EAT was independently associated with PWV. EAT may be associated with CVD risk due to an increase in systemic vascular inflammation. Whether targeting EAT may reduce inflammation and/or cardiovascular risk should be evaluated in prospective studies.

  7. Non-Newtonian Flow-Induced Deformation From Pressurized Cavities in Absorbing Porous Tissues

    Science.gov (United States)

    Ahmed, Aftab; Siddique, Javed

    2017-11-01

    We investigate the behavior of a spherical cavity in a soft biological tissue modeled as a deformable porous material during an injection of non-Newtonian fluid that follows a power law model. Fluid flows into the neighboring tissue due to high cavity pressure where it is absorbed by capillaries and lymphatics at a rate proportional to the local pressure. Power law fluid pressure and displacement of solid in the tissue are computed as function of radial distance and time. Numerical solutions indicate that shear thickening fluids exhibit less fluid pressure and induce small solid deformation as compared to shear thinning fluids. The absorption in the biological tissue increases as a consequence of flow induced deformation for power law fluids. In most cases non-Newtonian results are compared with viscous fluid case to magnify the differences.

  8. Hemodynamic effects of various support modes of continuous flow LVADs on the cardiovascular system: A numerical study

    Science.gov (United States)

    Song, Zhiming; Gu, Kaiyun; Gao, Bin; Wan, Feng; Chang, Yu; Zeng, Yi

    2014-01-01

    Background The aim of this study was to determine the hemodynamic effects of various support modes of continuous flow left ventricular assist devices (CF-LVADs) on the cardiovascular system using a numerical cardiovascular system model. Material/Methods Three support modes were selected for controlling the CF-LVAD: constant flow mode, constant speed mode, and constant pressure head mode of CF-LVAD. The CF-LVAD is established between the left ventricular apex and the ascending aorta, and was incorporated into the numerical model. Various parameters were evaluated, including the blood assist index (BAI), the left ventricular external work (LVEW), the energy of blood flow (EBF), pulsatility index (PI), and surplus hemodynamic energy (SHE). Results The results show that the constant flow mode, when compared to the constant speed mode and the constant pressure head mode, increases LVEW by 31% and 14%, and EBF by 21% and 15%, respectively, indicating that this mode achieved the best ventricular unloading among the 3 support modes. As BAI is increased, PI and SHE are gradually decreased, whereas PI of the constant pressure head reaches the maximum value. Conclusions The study demonstrates that the continuous flow control mode of the CF-LVAD may achieve the highest ventricular unloading. In contrast, the constant rotational speed mode permits the optimal blood perfusion. Finally, the constant pressure head strategy, permitting optimal pulsatility, should optimize the vascular function. PMID:24793178

  9. Color Doppler myocardial imaging demonstrates reduced diastolic tissue velocity in growth retarded fetuses with flow redistribution.

    Science.gov (United States)

    Larsen, Lene U; Petersen, Olav B; Sloth, Erik; Uldbjerg, Niels

    2011-04-01

    In fetuses suffering from intrauterine growth retardation with cerebroplacental redistribution (IUGR CPR), the diastolic heart function may be particularly susceptible to hypoxemia as described in postnatal pathological conditions. Using the newly introduced ultrasound technique, color Doppler myocardial imaging (CDMI), we investigated the correlation between diastolic tissue velocities and diastolic blood flow velocities and compared diastolic myocardial tissue velocities in fetuses with IUGR CPR and normal fetuses. Peak early and active atrial tissue velocities (E' and A') were acquired from both ventricular free walls in 18 fetuses with IUGR CPR and 42 normal fetuses. In 35 normal fetuses, blood flow across the atrio-ventricular valves was also recorded. Umbilical artery (UA), middle cerebral artery (MCA) and ductus venosus (DV) flows were obtained in all fetuses. Nonparametric tests were used for statistical analysis. There was a tendency towards increased E' and A' with fetal age in normal pregnancies. No correlation between tissue velocity and blood flow velocity was established. IUGR CPR fetuses had significantly lower E' and A', but when indexing to heart length, only A' remained significantly lower. E'/A' ratio was increased in the left ventricle but unchanged in the right. CDMI is easily applicable during standard fetal echocardiography and provides new information on the diastolic properties of the fetal myocardium. In fetuses with IUGR CPR, diastolic tissue velocities are abnormal and especially A' may be a marker of diastolic dysfunction. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  10. Oxygen supply and uptake in tissue models with unequal distribution of blood flow and shunt.

    Science.gov (United States)

    Piiper, J; Haab, P

    1991-05-01

    The effects of unequal distribution of blood flow on O2 uptake are studied on a model composed of 3 tissues compartments with blood flow/O2 requirement ratios in the relation 9:3:1 (unequal blood flow model), a model with 33% shunt blood flow (shunt model), and a single compartment model without shunt (reference model). Diffusion limitation is assumed to be absent. Total blood flow (Q), arterial O2 content (CaO2) and O2 requirement of tissue are varied singly, and the resulting (mixed) venous O2 content (CvO2) and O2 uptake are calculated. In the reference model, CvO2 become zero, and O2 uptake starts falling below the O2 requirement, as soon as the O2 delivery (Q.CaO2) becomes smaller than the O2 requirement. In contrast, in the unequal blood flow model, decrease in the ratio O2 uptake/O2 requirement and in CvO2 sets in earlier, and proceeds more gradually, with decreasing Q or CaO2 or increasing O2 requirement; this is, because O2 delivery limitation sets in sequentially in the compartments, starting with the least perfused compartment. The shunt model behaves similarly to the reference model if Q or O2 requirement is varied, and to the unequal blood flow model if CaO2 is varied. Some features such as the parallel fall of O2 uptake and of CVO2 with decreasing CaO2, common to the unequal blood flow and shunt models, are similar to expected effects of diffusion limitation. Therefore, when the influence of diffusion limitation on tissue O2 supply is to be investigated quantitatively, the effects of a possible unequal distribution of blood flow must be taken into account.

  11. Magnetic resonance imaging of the cardiovascular system

    International Nuclear Information System (INIS)

    Masuda, Yoshiaki; Imai, Hiroshi; Watanabe, Sigeru; Inagaki, Yoshiaki; Tateno, Yukio; Ikehira, Hiroo.

    1990-01-01

    Magnetic resonance imaging (MRI) is a new noninvasive technique for visualization of the cardiovascular system, and is used to evaluate tissue characteristics, cardiac function and blood flow abnormalities, as well as to obtain morphological information. In this paper we presented results of clinical and laboratory research obtained using conventional spin echo MRI with regard to cardiovascular anatomy, tissue characterization and physiology. Furthermore, experience with two new techniques, cine-MRI and volume-selected MR spectroscopy, and their potential clinical usefulness in detecting cardiovascular diseases are documented. (author)

  12. Loss of autoregulation of blood flow in subcutaneous tissue in juvenile diabetes

    DEFF Research Database (Denmark)

    Henriksen, O; Kastrup, J; Parving, H H

    1984-01-01

    The autoregulation of blood flow in subcutaneous tissue was investigated at the level of the lateral malleolus by the local 133Xenon washout technique. We have investigated eight long-term insulin-dependent diabetics and seven healthy controls. All diabetics had moderate diabetic nephropathy...... and retinopathy. The blood flow remained constant in all normal subjects, when the arterial perfusion pressure was varied between 70 and 150 mm Hg. All diabetics had impaired or reduced autoregulation of the subcutaneous blood flow. The blood flow increased and decreased almost linearly with the changes...... in arterial perfusion pressure. The mechanism underlying the defect autoregulation of blood flow in diabetics is uncertain; possibilities include structural changes of the arterioles and/or alterations of local metabolic factors....

  13. Effect of fractionated heating on the blood flow in normal tissues.

    Science.gov (United States)

    Lokshina, A M; Song, C W; Rhee, J G; Levitt, S H

    1985-01-01

    The changes in blood flow in the skin and muscle of rat by single, two or six heatings, were measured with the radioactive microsphere method. The blood flow rose continuously during the 2 h heatings at temperatures up to 43.0 degrees C and 44.0 degrees C in the skin and muscle, respectively. When heated at higher temperatures, the blood flow increased and then decreased. When heated twice at 43.5 degrees C for 1 h each, the magnitude of the increase in blood flow by the second heating varied depending on the time interval between the two heatings; e.g., the second heating on the 14th day after the first heating induced an increase in blood flow much greater than that by the first heating. When the heating at 43.5 degrees C for 1 h was repeated at intervals of five days, the second and third heatings were as effective as the first heating in increasing the skin blood flow. In the muscle, the second and third heatings were 2-3-fold more effective than the first heating in raising the blood flow. The heat-induced increase in blood flow in the skin and muscle gradually diminished from the fourth heating. The tissue temperature varied considerably during heating with a water bath at a constant temperature, due probably to the changes in blood flow.

  14. Myocardial tissue characterization in Chagas' heart disease by cardiovascular magnetic resonance.

    Science.gov (United States)

    Torreão, Jorge A; Ianni, Barbara M; Mady, Charles; Naia, Evandro; Rassi, Carlos H; Nomura, Cesar; Parga, José R; Avila, Luis F; Ramires, José A F; Kalil-Filho, Roberto; Rochitte, Carlos E

    2015-11-18

    Chagas' heart disease is an important public health problem in South America. Several aspects of the pathogenesis are not fully understood, especially in its subclinical phases. On pathology Chagas' heart disease is characterized by chronic myocardial inflammation and extensive myocardial fibrosis. The latter has also been demonstrated by late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR). In three clinical phases of this disease, we sought to investigate the presence of LGE, myocardial increase in signal intensity in T2-weighted images (T2W) and in T1-weighted myocardial early gadolinium enhancement (MEGE), previously described CMR surrogates for myocardial fibrosis, myocardial edema and hyperemia, respectively. Fifty-four patients were analyzed. Sixteen patients with the indeterminate phase (IND), seventeen patients with the cardiac phase with no left ventricular systolic dysfunction (CPND), and twenty-one patients with the cardiac phase with left ventricular systolic dysfunction (CPD). All patients underwent 1.5 T CMR scan including LGE, T2W and MEGE image sequences to evaluate myocardial abnormalities. Late gadolinium enhancement was present in 72.2 % of all patients, in 12.5 % of IND, 94.1 % of the CPND and 100 % of the CPD patients (p < 0.0001). Myocardial increase in signal intensity in T2-weighted images (T2W) was present in 77.8 % of all patients, in 31.3 % of the IND, 94.1 % of the CPND and 100 % of the CPD patients (p < 0.0001). T1-weighted myocardial early gadolinium enhancement (MEGE) was present in 73.8 % of all patients, in 25.0 % of the IND, 92.3 % of the CPND and 94.1 % of the CPD (p < 0.0001). A good correlation between LGE and T2W was observed (r = 0.72, and p < 0.001). Increase in T2-weighted (T2W) myocardial signal intensity and T1-weighted myocardial early gadolinium enhancement (MEGE) can be detected by CMR in patients throughout all phases of Chagas' heart disease, including its

  15. Subcutaneous adipose tissue blood flow in the forefoot during 24 hours. Labeling pattern and reproducibility

    DEFF Research Database (Denmark)

    Jelnes, Rolf; Bülow, J; Tønnesen, K H

    1987-01-01

    (range: 3-90 days). The patients were studied under two different conditions. Firstly, during the day in the erect position, awake (sitting, standing and quiet walking) and secondly, during night hours in the supine position, asleep. The coefficient of variation of nocturnal adipose tissue blood flow...... was calculated to 10%, and for the ratio of blood flow from day to night to 5%. The method is thus considered apt as a monitor in the treatment of peripheral vascular disease, for example, surgery and medical therapy. As predominant source of error is the formation of oedema....

  16. Review of Zero-D and 1-D Models of Blood Flow in the Cardiovascular System

    Science.gov (United States)

    2011-01-01

    Background Zero-dimensional (lumped parameter) and one dimensional models, based on simplified representations of the components of the cardiovascular system, can contribute strongly to our understanding of circulatory physiology. Zero-D models provide a concise way to evaluate the haemodynamic interactions among the cardiovascular organs, whilst one-D (distributed parameter) models add the facility to represent efficiently the effects of pulse wave transmission in the arterial network at greatly reduced computational expense compared to higher dimensional computational fluid dynamics studies. There is extensive literature on both types of models. Method and Results The purpose of this review article is to summarise published 0D and 1D models of the cardiovascular system, to explore their limitations and range of application, and to provide an indication of the physiological phenomena that can be included in these representations. The review on 0D models collects together in one place a description of the range of models that have been used to describe the various characteristics of cardiovascular response, together with the factors that influence it. Such models generally feature the major components of the system, such as the heart, the heart valves and the vasculature. The models are categorised in terms of the features of the system that they are able to represent, their complexity and range of application: representations of effects including pressure-dependent vessel properties, interaction between the heart chambers, neuro-regulation and auto-regulation are explored. The examination on 1D models covers various methods for the assembly, discretisation and solution of the governing equations, in conjunction with a report of the definition and treatment of boundary conditions. Increasingly, 0D and 1D models are used in multi-scale models, in which their primary role is to provide boundary conditions for sophisticate, and often patient-specific, 2D and 3D models

  17. Review of Zero-D and 1-D Models of Blood Flow in the Cardiovascular System

    Directory of Open Access Journals (Sweden)

    Hose Rodney

    2011-04-01

    Full Text Available Abstract Background Zero-dimensional (lumped parameter and one dimensional models, based on simplified representations of the components of the cardiovascular system, can contribute strongly to our understanding of circulatory physiology. Zero-D models provide a concise way to evaluate the haemodynamic interactions among the cardiovascular organs, whilst one-D (distributed parameter models add the facility to represent efficiently the effects of pulse wave transmission in the arterial network at greatly reduced computational expense compared to higher dimensional computational fluid dynamics studies. There is extensive literature on both types of models. Method and Results The purpose of this review article is to summarise published 0D and 1D models of the cardiovascular system, to explore their limitations and range of application, and to provide an indication of the physiological phenomena that can be included in these representations. The review on 0D models collects together in one place a description of the range of models that have been used to describe the various characteristics of cardiovascular response, together with the factors that influence it. Such models generally feature the major components of the system, such as the heart, the heart valves and the vasculature. The models are categorised in terms of the features of the system that they are able to represent, their complexity and range of application: representations of effects including pressure-dependent vessel properties, interaction between the heart chambers, neuro-regulation and auto-regulation are explored. The examination on 1D models covers various methods for the assembly, discretisation and solution of the governing equations, in conjunction with a report of the definition and treatment of boundary conditions. Increasingly, 0D and 1D models are used in multi-scale models, in which their primary role is to provide boundary conditions for sophisticate, and often patient

  18. Review of zero-D and 1-D models of blood flow in the cardiovascular system.

    Science.gov (United States)

    Shi, Yubing; Lawford, Patricia; Hose, Rodney

    2011-04-26

    Zero-dimensional (lumped parameter) and one dimensional models, based on simplified representations of the components of the cardiovascular system, can contribute strongly to our understanding of circulatory physiology. Zero-D models provide a concise way to evaluate the haemodynamic interactions among the cardiovascular organs, whilst one-D (distributed parameter) models add the facility to represent efficiently the effects of pulse wave transmission in the arterial network at greatly reduced computational expense compared to higher dimensional computational fluid dynamics studies. There is extensive literature on both types of models. The purpose of this review article is to summarise published 0D and 1D models of the cardiovascular system, to explore their limitations and range of application, and to provide an indication of the physiological phenomena that can be included in these representations. The review on 0D models collects together in one place a description of the range of models that have been used to describe the various characteristics of cardiovascular response, together with the factors that influence it. Such models generally feature the major components of the system, such as the heart, the heart valves and the vasculature. The models are categorised in terms of the features of the system that they are able to represent, their complexity and range of application: representations of effects including pressure-dependent vessel properties, interaction between the heart chambers, neuro-regulation and auto-regulation are explored. The examination on 1D models covers various methods for the assembly, discretisation and solution of the governing equations, in conjunction with a report of the definition and treatment of boundary conditions. Increasingly, 0D and 1D models are used in multi-scale models, in which their primary role is to provide boundary conditions for sophisticate, and often patient-specific, 2D and 3D models, and this application is also

  19. Combined statistical analysis of vasodilation and flow curves in brachial ultrasonography: technique and its connection to cardiovascular risk factors

    Science.gov (United States)

    Boisrobert, Loic; Laclaustra, Martin; Bossa, Matias; Frangi, Andres G.; Frangi, Alejandro F.

    2005-04-01

    Clinical studies report that impaired endothelial function is associated with Cardio-Vascular Diseases (CVD) and their risk factors. One commonly used mean for assessing endothelial function is Flow-Mediated Dilation (FMD). Classically, FMD is quantified using local indexes e.g. maximum peak dilation. Although such parameters have been successfully linked to CVD risk factors and other clinical variables, this description does not consider all the information contained in the complete vasodilation curve. Moreover, the relation between flow impulse and the vessel vasodilation response to this stimulus, although not clearly known, seems to be important and is not taken into account in the majority of studies. In this paper we propose a novel global parameterization for the vasodilation and the flow curves of a FMD test. This parameterization uses Principal Component Analysis (PCA) to describe independently and jointly the variability of flow and FMD curves. These curves are obtained using computerized techniques (based on edge detection and image registration, respectively) to analyze the ultrasound image sequences. The global description obtained through PCA yields a detailed characterization of the morphology of such curves allowing the extraction of intuitive quantitative information of the vasodilation process and its interplay with flow changes. This parameterization is consistent with traditional measurements and, in a database of 177 subjects, seems to correlate more strongly (and with more clinical parameters) than classical measures to CVD risk factors and clinical parameters such as LDL- and HDL-Cholesterol.

  20. Subcutaneous adipose tissue blood flow in the forefoot during 24 hours. Labeling pattern and reproducibility

    DEFF Research Database (Denmark)

    Jelnes, Rolf; Bülow, J; Tønnesen, K H

    1987-01-01

    (range: 3-90 days). The patients were studied under two different conditions. Firstly, during the day in the erect position, awake (sitting, standing and quiet walking) and secondly, during night hours in the supine position, asleep. The coefficient of variation of nocturnal adipose tissue blood flow......Wash-out of 133xenon from a local depot in the subcutaneous adipose tissue in the forefoot was measured continuously during 24 hours on subsequent recordings in 51 feet (normal circulation: 10, intermittent claudication: 22 and ischaemic nocturnal rest pain: 19) with a mean time interval of 26 days...... was calculated to 10%, and for the ratio of blood flow from day to night to 5%. The method is thus considered apt as a monitor in the treatment of peripheral vascular disease, for example, surgery and medical therapy. As predominant source of error is the formation of oedema....

  1. Evaluation of Cardiovascular System in Fibromyalgia Syndrome: Tissue Doppler Echocardiographic Investigation

    Directory of Open Access Journals (Sweden)

    Selma YAZICI

    2010-05-01

    Full Text Available Aim: We aim to investigate besides the cardiac structures and functions by both conventionalmethods and Tissue Doppler Echocardiography (TDE which is a new and useful method inpatients with Fibromyalgia (FM. Additionally, we evaluated QT parameters (QT maximum,QT minimum and QT dispertion with the use of electrocardiography in order to measure theautonomic dysfunction which is a possible mechanism in the pathogenesis of the disease. Methods: The study was performed on 42 patients (mean age 41 years, 38 female and 38completely healthy subjects (35 female, mean age of 42 years who were admitted to the sameclinic were collected as the control group. All the individuals were undergone a completephysical examination, electrocardiography (recordings were displayed at 50 mm/s speed andechocardiography evaluation (both conventional methods and TDE.Results: Analysis of electrocardiographic recordings revealed mildly increased mean QTdispertion in the patient group, but this difference was statistically insignificant. Analysis ofconventional echocardiographic parameters revealed similar results between the patient groupand the control cases. However, an important finding of this study is that significant diastolicdysfunction was found in the patient group which was recorded with the TDE technique. Emwave velocity and Em/Am ratios were significantly lower in patients with FM compared withcontrols (p<0.005, p<0.01, respectively. Sm and Am waves velocities were similar in bothgroups. Conclusion: In this study, significant left ventricular diastolic dysfunction which was detectedby TDE technique can partly explain several symptoms such as fatigue and dyspnea in FM. Inaddition, fully cardiac evaluation of patients with FM might be obtained supporting findingsthe autonomic dysfunction theory in fibromyalgia pathogenesis.

  2. Exercise Effects on Adipose Tissue Postprandial Lipolysis and Blood Flow in Children.

    Science.gov (United States)

    Yan, Huimin; Pierce, Joseph R; Myers, Kimberly B; DuBose, Katrina D; Dubis, Gabriel S; Tanner, Charles J; Hickner, Robert C

    2018-01-30

    Poor suppression of lipolysis and blunted increase in blood flow following meal ingestion in obese adults may indicate resistance to the antilipolytic action of insulin. Exercise may be used to normalize lipolytic responses to food intake by increasing insulin sensitivity. To determine if acute bouts of aerobic exercise and/or excise training alter lipolytic and blood flow responses to food intake in lean (LN) and obese (OB) children. Sixty-five children (9-11 yrs) were randomized into acute exercise (EX: 16 LN and 28 OB) or control (CON: 9 LN and 12 OB) groups that exercised (EX), or rested (CON) between standardized breakfast and lunch. Microdialysis probes were inserted into the subcutaneous abdominal adipose tissue to monitor interstitial glycerol (lipolysis) and blood flow. Changes in interstitial glycerol and nutritive flow were calculated from dialysate samples before and after each meal. A subgroup (OB=15 and LN=9) from the acute exercise group underwent 16 weeks of aerobic exercise training. Poor suppression of lipolysis and a blunted increase in adipose tissue nutritive blood flow in response to breakfast was associated with BMI percentile (r=0.3, p<0.05). These responses were normalized at lunch in the OB in the EX (p<0.05), but not in OB in the CON. Sixteen weeks of exercise training did not improve meal-induced blood flow, and marginally altered the antilipolytic response to the two meals (p=0.06). Daily bouts of acute aerobic exercise should be used to improve the antilipolytic and nutritive blood flow response to a subsequent meal in obese children.

  3. Relationship between coronary flow reserve evaluated by phase-contrast cine cardiovascular magnetic resonance and serum eicosapentaenoic acid

    Science.gov (United States)

    2013-01-01

    Background Long-term intake of long-chain n-3 polyunsaturated fatty acids (n-3 PUFAs), especially eicosapentaenoic acid (EPA) is associated with a low risk for cardiovascular disease. Phase-contrast cine cardiovascular magnetic resonance (PC cine CMR) can assess coronary flow reserve (CFR). The present study investigates the relationship between CFR evaluated by PC cine CMR and the serum EPA. Methods We studied 127 patients (male, 116 (91%); mean age, 72.2 ± 7.4 years) with known or suspected coronary artery disease (CAD). X-ray coronary angiography revealed no significant coronary arterial stenoses (defined as luminal diameter reduction ≥50% on quantitative coronary angiogram (QCA) analysis) in all study participants. Breath-hold PC cine CMR images of the coronary sinus (CS) were acquired to assess blood flow of the CS both at rest and during adenosine triphosphate (ATP) infusion. We calculated CFR as CS blood flow during ATP infusion divided by that at rest. Patients were allocated to groups according to whether they had high (n = 64, EPA ≥ 75.8 μg/mL) or low (n = 63, EPA  2.5, which is the previously reported lower limit of normal flow reserve without obstructive CAD. Multivariate analysis revealed that EPA is an independent predictor of CFR > 2.5 (odds ratio, 1.01; 95% confidence interval, 1.00 – 1.02, p = 0.008). Conclusions The serum EPA is significantly correlated with CFR in CAD patients without significant coronary artery stenosis. PMID:24359564

  4. Blood transfusion in preterm infants improves intestinal tissue oxygenation without alteration in blood flow.

    Science.gov (United States)

    Banerjee, J; Leung, T S; Aladangady, N

    2016-11-01

    The objective of the study was to investigate the splanchnic blood flow velocity and oximetry response to blood transfusion in preterm infants according to postnatal age. Preterm infants receiving blood transfusion were recruited to three groups: 1-7 (group 1; n = 20), 8-28 (group 2; n = 21) and ≥29 days of life (group 3; n = 18). Superior mesenteric artery (SMA) peak systolic (PSV) and diastolic velocities were measured 30-60 min pre- and post-transfusion using Doppler ultrasound scan. Splanchnic tissue haemoglobin index (sTHI), tissue oxygenation index (sTOI) and fractional tissue oxygen extraction (sFTOE) were measured from 15-20 min before to post-transfusion using near-infrared spectroscopy. The mean pretransfusion Hb in group 1, 2 and 3 was 11, 10 and 9 g/dl, respectively. The mean (SD) pretransfusion SMA PSV in group 1, 2 and 3 was 0·63 (0·32), 0·81 (0·33) and 0·97 (0·40) m/s, respectively, and this did not change significantly following transfusion. The mean (SD) pretransfusion sTOI in group 1, 2 and 3 was 36·7 (19·3), 44·6 (10·4) and 41·3 (10·4)%, respectively. The sTHI and sTOI increased (P transfusion in all groups. On multivariate analysis, changes in SMA PSV and sTOI following blood transfusion were not associated with PDA, feeding, pretransfusion Hb and mean blood pressure. Pretransfusion baseline splanchnic tissue oximetry and blood flow velocity varied with postnatal age. Blood transfusion improved intestinal tissue oxygenation without altering mesenteric blood flow velocity irrespective of postnatal ages. © 2016 International Society of Blood Transfusion.

  5. Flow characteristics of soft-tissue vascular anomalies evaluated by direct puncture scintigraphy

    International Nuclear Information System (INIS)

    Inoue, Yusuke; Ohtake, Tohru; Wakita, Shinichi; Yoshioka, Naoki; Furuya, Fujio; Nishikawa, Junichi; Sasaki, Yasuhito; Harii, Kiyonori

    1997-01-01

    We have developed a new method, direct puncture scintigraphy, to evaluate in detail the haemodynamics of vascular anomalies under conditions simulating sclerotherapy. Twenty-six soft-tissue vascular anomalies in 21 patients were studied. After 30 MBq of technetium-99m Sn colloid was injected percutaneously into the intravascular space of the lesion, dynamic imaging was performed for 5 min. A time-activity curve for the lesion was generated, with the infiltrated activity on injection subtracted. A monoexponential curve was fitted to the declining phase of the time-activity curve, and mean vascular transit time (MTT) was obtained. The lesions were classified into high-flow and low-flow lesions based on radionuclide angiography with intravenous injection of 99m Tc-labelled red blood cells, and estimates of MTT in the two groups were compared. The imaging procedures were carried out with no major complications, and broad intralesional diffusion of 99m Tc-Sn colloid was achieved in most lesions. The high-flow lesions (six lesions) had a short MTT, ranging from 1.6 to 3.4 s, while the low-flow lesions (20 lesions) had a longer MTT, with no overlap between the groups. MTT showed a wide range in low-flow lesions: it was less than 30 s in six lesions and more than 10 min in five other lesions. Direct puncture scintigraphy provides a quantitative indicator of the flow characteristics of soft-tissue vascular anomalies, and may aid in determining treatment strategies for patients with vascular anomalies. (orig./VHE). With 4 figs

  6. Diet-induced changes in subcutaneous adipose tissue blood flow in man: effect of beta-adrenoceptor inhibition

    DEFF Research Database (Denmark)

    Simonsen, L; Bülow, J; Astrup, A

    1990-01-01

    The effect of a carbohydrate-rich meal on subcutaneous adipose tissue blood flow was studied with and without continuous i.v. infusion of propranolol in healthy volunteers. The subcutaneous adipose tissue blood flow was measured with the 133Xe washout method in three different locations......: the forearm, the thigh and the abdomen. The subjects were given a meal consisting of white bread, jam, honey and apple juice (about 2300 kJ). The meal induced a twofold increase in blood flow in the examined tissues. Propranolol abolished the flow increase in the thigh and the abdomen and reduced...... it in the forearm. This indicates that the mechanism for the flow increase is elicited by a stimulation of vascular beta-adrenoceptors in the subcutaneous adipose tissue, since the beta-adrenoceptor inhibition did not affect the overall metabolic and hormonal responses to the meal....

  7. Increased visceral adipose tissue and altered adiposity distribution in premenopausal lupus patients: correlation with cardiovascular risk factors.

    Science.gov (United States)

    Seguro, L P C; Paupitz, J A; Caparbo, V F; Bonfa, E; Pereira, R M R

    2018-01-01

    Objective Visceral adipose tissue (VAT) correlates with cardiovascular risk factors and has never been assessed in systemic lupus erythematosus (SLE). Our aim was to evaluate VAT in premenopausal SLE patients. Methods Sixty-three premenopausal SLE patients and 186 age-matched healthy women were included. Demographic, anthropometric, disease and treatment parameters were evaluated. VAT was measured by dual X-ray absorptiometry (DXA) with APEX 4.0 software. Results SLE patients had a disease duration of 5.25 ± 3.80 years, SLEDAI activity score of 4.35 ± 5.13, SLICC/ACR-DI of 0.70 ± 0.80, current prednisone dose of 11.60 ± 12.10 mg/day and cumulative glucocorticoid dose of 22.34 ± 12.94 g. Overweight/obese SLE patients and controls had similar VAT parameters ( p > 0.05). Among individuals with BMI  0.05) but patients had higher values of VAT parameters (VAT mass: 260.60 ± 117.23 vs. 194.77 ± 71.42 g, p = 0.001; VAT area: 54.05 ± 24.30 vs. 40.40 ± 14.82 cm 2 , p = 0.001; VAT volume: 281.75 ± 126.81 vs. 210.61 ± 77.29 cm 3 , p = 0.001) and trunk/limb fat mass ratio (0.78 ± 0.21 vs. 0.67 ± 0.12, p = 0.002) compared to controls. In SLE, VAT area correlated with weight ( r = 0.66, p  0.05). Conclusion This study provides original evidence that SLE is associated with increased VAT and altered adiposity distribution. The correlation with traditional risk factors for cardiovascular disease, independent of current glucocorticoid dose and disease activity, suggests the role of visceral fat as an additional tool for risk assessment in these young patients.

  8. Flow-dependent re-endothelialization of tissue-engineered heart valves.

    Science.gov (United States)

    Lichtenberg, Artur; Cebotari, Serghei; Tudorache, Igor; Sturz, Gerrit; Winterhalter, Michael; Hilfiker, Andres; Haverich, Axel

    2006-03-01

    The generation of a functional, non-immunogenic, non-thrombogenic construct based on autologous cells seeded onto an acellular extracellular matrix is the major goal in heart valve tissue engineering. The study aim was to identify culturing conditions required to achieve a stable endothelial cell (EC) layer under physiological flow conditions, a prerequisite for the requested characteristics. Eleven detergent-decellularized ovine pulmonary valves (PVs) were statically reseeded in special bioreactors with ovine venous ECs (1.2x10(7) cells per valve). The dynamic culture was started with 0.1 l/min in eight bioreactors. In four bioreactors the initial flow rate was slow, and increased by 0.1 l/min twice each day until maximal flow was 0.5 l/min and pulsation rate (PR) was 20 beats/min; in four other bioreactors the flow was increased by 0.7 l/min/day and reached 2.0 l/min with a PR of 50 beats/min. The mean system pressure was maintained at 25 +/- 5 mmHg during the whole dynamic cultivation in both groups. Three statically reseeded valves served as baseline. After achieving maximal appointed flow, the valves were investigated morphologically (hematoxylin and eosin staining, electron microscopy, von Willebrand factor, endothelial nitric oxide synthase immunostaining) and for metabolic activity (MTS assay). After reseeding, the endothelium appeared on the luminal surface of the PV as a non-confluent monolayer. Moderate pulsatile circulation induced complete confluence of EC monolayers on both cusp sides and the pulmonary wall. A high flow rate led to a partial loss of cells on the wall surface with large defects, and to complete cell wash-off from cusps. Cusp and wall metabolic activity was significantly higher after culture under moderate flow (p valve scaffold. A rapid increase in bioreactor flow to physiological levels leads to significant damage of the reseeded endothelium and complete loss of cusp cellularity. This effect may be responsible for the in-vivo failure

  9. Flow rate of transport network controls uniform metabolite supply to tissue.

    Science.gov (United States)

    Meigel, Felix J; Alim, Karen

    2018-05-01

    Life and functioning of higher organisms depends on the continuous supply of metabolites to tissues and organs. What are the requirements on the transport network pervading a tissue to provide a uniform supply of nutrients, minerals or hormones? To theoretically answer this question, we present an analytical scaling argument and numerical simulations on how flow dynamics and network architecture control active spread and uniform supply of metabolites by studying the example of xylem vessels in plants. We identify the fluid inflow rate as the key factor for uniform supply. While at low inflow rates metabolites are already exhausted close to flow inlets, too high inflow flushes metabolites through the network and deprives tissue close to inlets of supply. In between these two regimes, there exists an optimal inflow rate that yields a uniform supply of metabolites. We determine this optimal inflow analytically in quantitative agreement with numerical results. Optimizing network architecture by reducing the supply variance over all network tubes, we identify patterns of tube dilation or contraction that compensate sub-optimal supply for the case of too low or too high inflow rate. © 2018 The Authors.

  10. Mechanotransduction in musculoskeletal tissue regeneration: effects of fluid flow, loading, and cellular-molecular pathways.

    Science.gov (United States)

    Qin, Yi-Xian; Hu, Minyi

    2014-01-01

    While mechanotransductive signal is proven essential for tissue regeneration, it is critical to determine specific cellular responses to such mechanical signals and the underlying mechanism. Dynamic fluid flow induced by mechanical loading has been shown to have the potential to regulate bone adaptation and mitigate bone loss. Mechanotransduction pathways are of great interests in elucidating how mechanical signals produce such observed effects, including reduced bone loss, increased bone formation, and osteogenic cell differentiation. The objective of this review is to develop a molecular understanding of the mechanotransduction processes in tissue regeneration, which may provide new insights into bone physiology. We discussed the potential for mechanical loading to induce dynamic bone fluid flow, regulation of bone adaptation, and optimization of stimulation parameters in various loading regimens. The potential for mechanical loading to regulate microcirculation is also discussed. Particularly, attention is allotted to the potential cellular and molecular pathways in response to loading, including osteocytes associated with Wnt signaling, elevation of marrow stem cells, and suppression of adipotic cells, as well as the roles of LRP5 and microRNA. These data and discussions highlight the complex yet highly coordinated process of mechanotransduction in bone tissue regeneration.

  11. Effect of bupivacaine and adjuvant drugs for regional anesthesia on nerve tissue oximetry and nerve blood flow.

    Science.gov (United States)

    Wiesmann, Thomas; Müller, Stefan; Müller, Hans-Helge; Wulf, Hinnerk; Steinfeldt, Thorsten

    2018-01-01

    Nerve blood flow has a critical role in acute and chronic pathologies in peripheral nerves. Influences of local anesthetics and adjuvants on tissue perfusion and oxygenation are deemed as relevant factors for nerve damage after peripheral regional anesthesia. The link between low tissue perfusion due to local anesthetics and resulting tissue oxygenation is unclear. Combined tissue spectrophotometry and laser-Doppler flowmetry were used to assess nerve blood flow in 40 surgically exposed median nerves in pigs, as well as nerve tissue oximetry for 60 min. After baseline measurements, test solutions saline (S), bupivacaine (Bupi), bupivacaine with epinephrine (BupiEpi), and bupivacaine with clonidine (BupiCloni) were applied topically. Bupivacaine resulted in significant decrease in nerve blood flow, as well as tissue oximetry values, compared with saline control. Addition of epinephrine resulted in a rapid, but nonsignificant, reduction of nerve blood flow and extensive lowering of tissue oximetry levels. The use of clonidine resulted in a reduction of nerve blood flow, comparable to bupivacaine alone (relative blood flow at T60 min compared with baseline, S: 0.86 (0.67-1.18), median (25th-75th percentile); Bupi: 0.33 (0.25-0.60); BupiCloni: 0.43 (0.38-0.63); and BupiEpi: 0.41(0.30-0.54). The use of adjuvants did not result in any relevant impairment of tissue oximetry values (saturation values in percent at T60, S: 91.5 [84-95]; Bupi: 76 [61-86]; BupiCloni: 84.5 [76-91]; and BupiEpi: 91 [56-92]). The application of bupivacaine results in lower nerve blood flow, but does not induce relevant ischemia. Despite significant reductions in nerve blood flow, the addition of clonidine or epinephrine to bupivacaine had no significant impact on nerve tissue oximetry compared with bupivacaine alone. Nerve ischemia due to local anesthetics is not enhanced by the adjuvants clonidine or epinephrine.

  12. A novel bioreactor for mechanobiological studies of engineered heart valve tissue formation under pulmonary arterial physiological flow conditions.

    Science.gov (United States)

    Ramaswamy, Sharan; Boronyak, Steven M; Le, Trung; Holmes, Andrew; Sotiropoulos, Fotis; Sacks, Michael S

    2014-12-01

    The ability to replicate physiological hemodynamic conditions during in vitro tissue development has been recognized as an important aspect in the development and in vitro assessment of engineered heart valve tissues. Moreover, we have demonstrated that studies aiming to understand mechanical conditioning require separation of the major heart valve deformation loading modes: flow, stretch, and flexure (FSF) (Sacks et al., 2009, "Bioengineering Challenges for Heart Valve Tissue Engineering," Annu. Rev. Biomed. Eng., 11(1), pp. 289-313). To achieve these goals in a novel bioreactor design, we utilized a cylindrical conduit configuration for the conditioning chamber to allow for higher fluid velocities, translating to higher shear stresses on the in situ tissue specimens while retaining laminar flow conditions. Moving boundary computational fluid dynamic (CFD) simulations were performed to predict the flow field under combined cyclic flexure and steady flow (cyclic-flex-flow) states using various combinations of flow rate, and media viscosity. The device was successfully constructed and tested for incubator housing, gas exchange, and sterility. In addition, we performed a pilot experiment using biodegradable polymer scaffolds seeded with bone marrow derived stem cells (BMSCs) at a seeding density of 5 × 10(6) cells/cm(2). The constructs were subjected to combined cyclic flexure (1 Hz frequency) and steady flow (Re = 1376; flow rate of 1.06 l/min (LPM); shear stress in the range of 0-9 dynes/cm(2) for 2 weeks to permit physiological shear stress conditions. Assays revealed significantly (P Engineered Tissue Formation: Implications for Engineered Heart Valve Tissues," Biomaterials, 27(36), pp. 6083-6095). The implications of this novel design are that fully coupled or decoupled physiological flow, flexure, and stretch modes of engineered tissue conditioning investigations can be readily accomplished with the inclusion of this device in experimental protocols on

  13. The incremental value of brachial flow-mediated dilation measurements in risk stratification for incident cardiovascular events: a systematic review.

    Science.gov (United States)

    Peters, Sanne A E; den Ruijter, Hester M; Bots, Michiel L

    2012-06-01

    Abstract Adequate risk assessment for cardiovascular disease (CVD) is essential as a guide to initiate drug treatment. Current methods based on traditional risk factors could be improved considerably. Although brachial flow-mediated dilation (FMD) predicts subsequent cardiovascular events, its predictive value on top of traditional risk factors is unknown. We performed a systematic review to evaluate the incremental predictive value of FMD on top of traditional risk factors in asymptomatic individuals. Using PubMed and reference tracking, three studies were identified that reported on the incremental value of FMD using change in the area under the curve (AUC). Two large cohort studies found no improvement in AUC when FMD was added to traditional risk prediction models, whereas one small case-control study found an improvement. One study used the net reclassification improvement (NRI) to assess whether FMD measurement leads to correct risk stratification in risk categories. Although this study did not find an improvement in AUC, the NRI was statistically significant. Based on the reclassification results of this study, FMD measurement might be helpful in risk prediction. Evidence supporting the use of FMD measurement in clinical practice for risk stratification for CVD on top of traditional risk factors is limited, and future studies are needed.

  14. Rapid release of active tissue factor from human arterial smooth muscle cells under flow conditions.

    Science.gov (United States)

    Stampfuss, Jan-Julius; Censarek, Petra; Fischer, Jens W; Schrör, Karsten; Weber, Artur-Aron

    2006-05-01

    Circulating tissue factor (TF) is an important determinant of coronary thrombosis. Among other cell types, such as monocytes, vascular smooth muscle cells (SMCs) are capable of releasing TF. When studied under static conditions, SMCs do release TF, but this process is slow and, thus, cannot explain the elevated levels of circulating TF, as observed in patients with acute coronary syndromes. The present study demonstrates that cultured human mammary artery SMCs very rapidly (minutes) release active, microparticle-bound TF when exposed to flow conditions. There was a clear log-linear correlation between the shear rate (range 10 s(-1) to 1500 s(-1)) and the procoagulant activity of SMC perfusates. Flow-dependent release of TF was transient (10 minutes) and did not measurably reduce cell surface TF content. Interestingly, a time-dependent (t(1/2) 30 minutes) re-exposure of releasable TF was detected after a no-flow period. These data demonstrate that SMCs may become a pathophysiologically relevant source of TF that can be rapidly released into the circulation in situations in which endothelial damage occurs and SMCs come into a close contact with the flowing blood.

  15. Bone tissue engineering using human mesenchymal stem cells: effects of scaffold material and medium flow.

    Science.gov (United States)

    Meinel, Lorenz; Karageorgiou, Vassilis; Fajardo, Robert; Snyder, Brian; Shinde-Patil, Vivek; Zichner, Ludwig; Kaplan, David; Langer, Robert; Vunjak-Novakovic, Gordana

    2004-01-01

    We report studies of bone tissue engineering using human mesenchymal stem cells (MSCs), a protein substrate (film or scaffold; fast degrading unmodified collagen, or slowly degrading cross-linked collagen and silk), and a bioreactor (static culture, spinner flask, or perfused cartridge). MSCs were isolated from human bone marrow, characterized for the expression of cell surface markers and the ability to undergo chondrogenesis and osteogenesis in vitro, and cultured for 5 weeks. MSCs were positive for CD105/endoglin, and had a potential for chondrogenic and osteogenic differentiation. In static culture, calcium deposition was similar for MSC grown on collagen scaffolds and films. Under medium flow, MSC on collagen scaffolds deposited more calcium and had a higher alcaline phosphatase (AP) activity than MSC on collagen films. The amounts of DNA were markedly higher in constructs based on slowly degrading (modified collagen and silk) scaffolds than on fast degrading (unmodified collagen) scaffolds. In spinner flasks, medium flow around constructs resulted in the formation of bone rods within the peripheral region, that were interconnected and perpendicular to the construct surface, whereas in perfused constructs, individual bone rods oriented in the direction of fluid flow formed throughout the construct volume. These results suggest that osteogenesis in cultured MSC can be modulated by scaffold properties and flow environment.

  16. Deuterium MR spectroscopy at 4.7 T. Quantification of tumour and subcutaneous tissue blood flow in animal models

    DEFF Research Database (Denmark)

    Wirestam, R; Larsen, V.A.; Stubgaard, M

    1995-01-01

    Deuterium MR spectroscopy was used for the determination of tissue blood flow (TBF). The tracer D2O was injected into the tissue of interest, and tracer washout was followed using a 4.7 T spectroscopy/imaging unit. Normal subcutaneous tissue in rats was studied, as well as tissue influenced...... by vasoactive agents (papaverine and adrenaline). The vasoactive agents introduced changes of 40% in TBF, compared with normal tissue. Normal tissue measurements were repeated using various D2O injection volumes (5-400 microliters). The injection volume 5 microliters gave TBF 11.7 +/- 2.0 ml/100 g.min (mean...... observed in dead rats. Blood flow measurements in human colon tumours implanted in nude mice showed a rather poor reproducibility, not improved by the use of a multiple site injection technique...

  17. Measurement of coronary flow response to cold pressor stress in asymptomatic women with cardiovascular risk factors using spiral velocity-encoded cine MRI at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Maroules, Christopher D.; Peshock, Ronald M. (Dept. of Radiology, Univ. of Texas Southwestern Medical Center, Dallas, TX (United States)), e-mail: Ron.Peshock@UTSouthwestern.edu; Chang, Alice Y.; Kontak, Andrew (Dept. of Internal Medicine, Univ. of Texas Southwestern Medical Center, Dallas, TX (United States)); Dimitrov, Ivan; Kotys, Melanie (Dept. of Philips Medical Systems, Cleveland, OH (United States))

    2010-05-15

    Background: Coronary sinus (CS) flow in response to a provocative stress has been used as a surrogate measure of coronary flow reserve, and velocity-encoded cine (VEC) magnetic resonance imaging (MRI) is an established technique for measuring CS flow. In this study, the cold pressor test (CPT) was used to measure CS flow response because it elicits an endothelium-dependent coronary vasodilation that may afford greater sensitivity for detecting early changes in coronary endothelial function. Purpose: To investigate the feasibility and reproducibility of CS flow reactivity (CSFR) to CPT using spiral VEC MRI at 3 Tesla in a sample of asymptomatic women with cardiovascular risk factors. Material and Methods: Fourteen asymptomatic women (age 38 years +- 10) with cardiovascular risk factors were studied using 3D spiral VEC MRI of the CS at 3 T. The CPT was utilized as a provocative stress to measure changes in CS flow. CSFR to CPT was calculated from the ratio of CS flow during peak stress to baseline CS flow. Results: CPT induced a significant hemodynamic response as measured by a 45% increase in rate-pressure product (P<0.01). A significant increase in CS volume flow was also observed (baseline, 116 +- 26 ml/min; peak stress, 152 +- 34 ml/min, P=0.01). CSFR to CPT was 1.31 +- 0.20. Test-retest variability of CS volume flow was 5% at baseline and 6% during peak stress. Conclusion: Spiral CS VEC MRI at 3 T is a feasible and reproducible technique for measuring CS flow in asymptomatic women at risk for cardiovascular disease. Significant changes in CSFR to CPT are detectable, without demanding pharmacologic stress

  18. Determination of adipose tissue blood flow with local 133Xe clearance. Evaluation of a new labelling technique

    DEFF Research Database (Denmark)

    Simonsen, Lene; Enevoldsen, Lotte Hahn; Bülow, Jens

    2003-01-01

    Adipose tissue blood flow was measured in six healthy, non-obese subjects with the xenon wash-out technique after labelling of the tissue by either injection of 133Xe dissolved in isotonic sodium chloride (water depot) or injection of 133Xe in gas form (gas depot). The wash-out rates were registe...

  19. Effect of Stress-free Therapy on Cerebral Blood Flow: Comparisons among patients with metabolic cardiovascular disease, healthy subjects and placebo-treated subjects

    Science.gov (United States)

    Ryotokuji, Kenji; Ishimaru, Keisou; Kihara, Kazuhiko; Namiki, Yoshihisa; Nakashima, Takuma; Otani, Satoru

    2014-01-01

    Background and aims: We have developed a Stress-free Therapy® device wherein “Pinpoint Plantar Long-wavelength Infrared Light Irradiation (PP-LILI)” increases peripheral-deep body temperature and blood flow volume and stabilizes blood pressure as well as significantly reduces stress hormones such as adrenocorticotrophic hormone and cortisol without using drugs. Moreover, we have found this therapy to significantly improve blood glucose and insulin resistance in patients with type 2 diabetes. Based on this background of clinical efficacy, we validated changes in cerebral blood flow in patients with metabolic cardiovascular disease and examined the efficacy of Stress-free Therapy® on cerebral blood flow as compared to that in healthy control subjects and placebo-treated patients. Results: The change in cerebral blood flow volume during 15-minute PP-LILI was 5.1 ± 1.8 mL/min in patients with metabolic cardiovascular disease, showing a significant increase (P<0.05) of 3.1 mL/min as compared with the mean blood flow value after resting for 15 minutes. Conclusions: Our results suggested Stress-free Therapy® to significantly increase cerebral blood flow, possibly leading to the prevention of metabolic cardiovascular disease. PMID:24771966

  20. Pericardial and thoracic peri-aortic adipose tissues contribute to systemic inflammation and calcified coronary atherosclerosis independent of body fat composition, anthropometric measures and traditional cardiovascular risks

    International Nuclear Information System (INIS)

    Yun, Chun-Ho; Lin, Tin-Yu; Wu, Yih-Jer; Liu, Chuan-Chuan; Kuo, Jen-Yuan; Yeh, Hung-I.; Yang, Fei-Shih; Chen, Su-Chiu; Hou, Charles Jia-Yin; Bezerra, Hiram G.; Hung, Chung-Lieh; Cury, Ricardo C.

    2012-01-01

    Background: Coronary atherosclerosis has traditionally been proposed to be associated with several cardiovascular risk factors and anthropometric measures. However, clinical data regarding the independent value of visceral adipose tissue in addition to such traditional predictors remains obscure. Materials and methods: We subsequently studied 719 subjects (age: 48.1 ± 8.3 years, 25% females) who underwent multidetector computed tomography (MDCT) for coronary calcium score (CCS) quantification. Baseline demographic data and anthropometric measures were taken with simultaneous body fat composition estimated. Visceral adipose tissue of pericardial and thoracic peri-aortic fat was quantified by MDCT using TeraRecon Aquarius workstation (San Mateo, CA). Traditional cardiovascular risk stratification was calculated by metabolic (NCEP ATP III) and Framingham (FRS) scores and high-sensitivity CRP (Hs-CRP) was taken to represent systemic inflammation. The independent value of visceral adipose tissue to systemic inflammation and CCS was assessed by utilizing multivariable regression analysis. Results: Of all subjects enrolled in this study, the mean values for pericardial and peri-aortic adipose tissue were 74.23 ± 27.51 and 7.23 ± 3.69 ml, respectively. Higher visceral fat quartile groups were associated with graded increase of risks for cardiovascular diseases. Both adipose burdens strongly correlated with anthropometric measures including waist circumference, body weight and body mass index (all p < 0.001). In addition, both visceral amount correlates well with ATP and FRS scores, all lipid profiles and systemic inflammation marker in terms of Hs-CRP (all p < 0.001). After adjustment for baseline variables, both visceral fat were independently related to Hs-CRP levels (all p < 0.05), but only pericardial fat exerted independent role in coronary calcium deposit. Conclusion: Both visceral adipose tissues strongly correlated with systemic inflammation beyond traditional

  1. The effects of particle size, shape, density and flow characteristics on particle margination to vascular walls in cardiovascular diseases.

    Science.gov (United States)

    Ta, Hang T; Truong, Nghia P; Whittaker, Andrew K; Davis, Thomas P; Peter, Karlheinz

    2018-01-01

    Vascular-targeted drug delivery is a promising approach for the treatment of atherosclerosis, due to the vast involvement of endothelium in the initiation and growth of plaque, a characteristic of atherosclerosis. One of the major challenges in carrier design for targeting cardiovascular diseases (CVD) is that carriers must be able to navigate the circulation system and efficiently marginate to the endothelium in order to interact with the target receptors. Areas covered: This review draws on studies that have focused on the role of particle size, shape, and density (along with flow hemodynamics and hemorheology) on the localization of the particles to activated endothelial cell surfaces and vascular walls under different flow conditions, especially those relevant to atherosclerosis. Expert opinion: Generally, the size, shape, and density of a particle affect its adhesion to vascular walls synergistically, and these three factors should be considered simultaneously when designing an optimal carrier for targeting CVD. Available preliminary data should encourage more studies to be conducted to investigate the use of nano-constructs, characterized by a sub-micrometer size, a non-spherical shape, and a high material density to maximize vascular wall margination and minimize capillary entrapment, as carriers for targeting CVD.

  2. Bioreactor-based bone tissue engineering: The influence of dynamic flow on osteoblast phenotypic expression and matrix mineralization

    OpenAIRE

    Yu, Xiaojun; Botchwey, Edward A.; Levine, Elliot M.; Pollack, Solomon R.; Laurencin, Cato T.

    2004-01-01

    An important issue in tissue engineering concerns the possibility of limited tissue ingrowth in tissue-engineered constructs because of insufficient nutrient transport. We report a dynamic flow culture system using high-aspect-ratio vessel rotating bioreactors and 3D scaffolds for culturing rat calvarial osteoblast cells. 3D scaffolds were designed by mixing lighter-than-water (density, 1g/ml) microspheres of 85:15 poly(lactide-co-glycolide). We quantified the rate of 3D flow through the scaf...

  3. Interscapular brown adipose tissue blood flow in the rat. Determination with 133xenon clearance compared to the microsphere method

    DEFF Research Database (Denmark)

    Astrup, A; Bülow, J; Madsen, J

    1984-01-01

    The xenon clearance method was adapted to continuous measurement of interscapular brown adipose tissue (ISBAT) blood flow in anesthetized rats. The ISBAT-blood partition coefficient for xenon was determined to 3.6 ml X g-1. The blood flow values obtained by Xe clearance were compared with flow...... values obtained concomitantly by the microsphere technique in 17 cold acclimated rats, at ISBAT blood flows between 0.1 and 6 ml X g-1 X min-1. Variations in blood flows were obtained by infusion of noradrenaline at different rates. The blood flow values obtained from the xenon clearance method showed...... a close correlation to the blood flow values determined with microspheres. Y = 0.98. X + 0.15 (r = 0.96, P less than 0.001). The Xe clearance method has the advantages compared to the microsphere technique that it permits continuous monitoring of the blood flow and does not require the sacrifice...

  4. Epicardial Adipose Tissue (EAT) Thickness Is Associated with Cardiovascular and Liver Damage in Nonalcoholic Fatty Liver Disease.

    Science.gov (United States)

    Fracanzani, Anna Ludovica; Pisano, Giuseppina; Consonni, Dario; Tiraboschi, Silvia; Baragetti, Andrea; Bertelli, Cristina; Norata, Giuseppe Danilo; Dongiovanni, Paola; Valenti, Luca; Grigore, Liliana; Tonella, Tatiana; Catapano, Alberico; Fargion, Silvia

    2016-01-01

    Epicardial adipose tissue (EAT) has been proposed as a cardiometabolic and hepatic fibrosis risk factor in patients with non alcoholic fatty liver disease (NAFLD). Aim of this study was to evaluate the role of EAT in NAFLD by analyzing 1) the association between EAT, the other metabolic parameters and the severity of steatosis 2) the relationship between cardiovascular (cIMT, cplaques, E/A), liver (presence of NASH and significant fibrosis) damage and metabolic risk factors including EAT 3) the relationship between EAT and genetic factors strongly influencing liver steatosis. In a cross-sectional study, we considered 512 consecutive patients with NAFLD (confirmed by biopsy in 100). EAT, severity of steatosis, carotid intima-media thickness (cIMT) and plaques were evaluated by ultrasonography and results analysed by multiple linear and logistic regression models. Variables independently associated with EAT (mm) were female gender (p = 0.003), age (p = 0.001), BMI (p = 0.01), diastolic blood pressure (p = 0.009), steatosis grade 2 (p = 0.01) and 3 (p = 0.04), fatty liver index (p = 0.001) and statin use (p = 0.03). Variables independently associated with carotid IMT were age (p = 0.0001), hypertension (p = 0.009), diabetes (p = 0.04), smoking habits (p = 0.04) and fatty liver index (p = 0.02), with carotid plaques age (p = 0.0001), BMI (p = 0.03), EAT (p = 0.02),) and hypertension (p = 0.02), and with E/A age (p = 0.0001), diabetes (p = 0.005), hypertension (p = 0.04) and fatty liver index (p = 0.004). In the 100 patients with available liver histology non alcoholic steatohepatitis (NASH) was independently associated with EAT (p = 0.04) and diabetes (p = 0.054) while significant fibrosis with EAT (p = 0.02), diabetes (p = 0.01) and waist circumference (p = 0.05). No association between EAT and PNPLA3 and TM6SF2 polymorphisms was found. In patients with NAFLD, EAT is associated with the severity of liver and vascular damage besides with the known metabolic risk

  5. Epicardial Adipose Tissue (EAT Thickness Is Associated with Cardiovascular and Liver Damage in Nonalcoholic Fatty Liver Disease.

    Directory of Open Access Journals (Sweden)

    Anna Ludovica Fracanzani

    Full Text Available Epicardial adipose tissue (EAT has been proposed as a cardiometabolic and hepatic fibrosis risk factor in patients with non alcoholic fatty liver disease (NAFLD. Aim of this study was to evaluate the role of EAT in NAFLD by analyzing 1 the association between EAT, the other metabolic parameters and the severity of steatosis 2 the relationship between cardiovascular (cIMT, cplaques, E/A, liver (presence of NASH and significant fibrosis damage and metabolic risk factors including EAT 3 the relationship between EAT and genetic factors strongly influencing liver steatosis.In a cross-sectional study, we considered 512 consecutive patients with NAFLD (confirmed by biopsy in 100. EAT, severity of steatosis, carotid intima-media thickness (cIMT and plaques were evaluated by ultrasonography and results analysed by multiple linear and logistic regression models. Variables independently associated with EAT (mm were female gender (p = 0.003, age (p = 0.001, BMI (p = 0.01, diastolic blood pressure (p = 0.009, steatosis grade 2 (p = 0.01 and 3 (p = 0.04, fatty liver index (p = 0.001 and statin use (p = 0.03. Variables independently associated with carotid IMT were age (p = 0.0001, hypertension (p = 0.009, diabetes (p = 0.04, smoking habits (p = 0.04 and fatty liver index (p = 0.02, with carotid plaques age (p = 0.0001, BMI (p = 0.03, EAT (p = 0.02, and hypertension (p = 0.02, and with E/A age (p = 0.0001, diabetes (p = 0.005, hypertension (p = 0.04 and fatty liver index (p = 0.004. In the 100 patients with available liver histology non alcoholic steatohepatitis (NASH was independently associated with EAT (p = 0.04 and diabetes (p = 0.054 while significant fibrosis with EAT (p = 0.02, diabetes (p = 0.01 and waist circumference (p = 0.05. No association between EAT and PNPLA3 and TM6SF2 polymorphisms was found.In patients with NAFLD, EAT is associated with the severity of liver and vascular damage besides with the known metabolic risk factors.

  6. Evaluation of heart tissue viability under redox-magnetohydrodynamics conditions: toward fine-tuning flow in biological microfluidics applications.

    Science.gov (United States)

    Cheah, Lih Tyng; Fritsch, Ingrid; Haswell, Stephen J; Greenman, John

    2012-07-01

    A microfluidic system containing a chamber for heart tissue biopsies, perfused with Krebs-Henseleit buffer containing glucose and antibiotic (KHGB) using peristaltic pumps and continuously stimulated, was used to evaluate tissue viability under redox-magnetohydrodynamics (redox-MHD) conditions. Redox-MHD possesses unique capabilities to control fluid flow using ionic current from oxidation and reduction processes at electrodes in a magnetic field, making it attractive to fine-tune fluid flow around tissues for "tissue-on-a-chip" applications. The manuscript describes a parallel setup to study two tissue samples simultaneously, and 6-min static incubation with Triton X100. Tissue viability was subsequently determined by assaying perfusate for lactate dehydrogenase (LDH) activity, where LDH serves as an injury marker. Incubation with KHGB containing 5 mM hexaammineruthenium(III) (ruhex) redox species with and without a pair of NdFeB magnets (∼ 0.39 T, placed parallel to the chamber) exhibited no additional tissue insult. MHD fluid flow, viewed by tracking microbeads with microscopy, occurred only when the magnet was present and stimulating electrodes were activated. Pulsating MHD flow with a frequency similar to the stimulating waveform was superimposed over thermal convection (from a hotplate) for Triton-KHGB, but fluid speed was up to twice as fast for ruhex-Triton-KHGB. A large transient ionic current, achieved when switching on the stimulating electrodes, generates MHD perturbations visible over varying peristaltic flow. The well-controlled flow methodology of redox-MHD is applicable to any tissue type, being useful in various drug uptake and toxicity studies, and can be combined equally with on- or off-device analysis modalities. Copyright © 2012 Wiley Periodicals, Inc.

  7. Effect of bupivacaine and adjuvant drugs for regional anesthesia on nerve tissue oximetry and nerve blood flow

    Directory of Open Access Journals (Sweden)

    Wiesmann T

    2018-01-01

    Full Text Available Thomas Wiesmann,1 Stefan Müller,1,2 Hans-Helge Müller,3 Hinnerk Wulf,1 Thorsten Steinfeldt1,4 1Department of Anesthesiology and Intensive Care Medicine, Faculty of Medicine, University Hospital Marburg, Philipps University, Marburg, 2Department of Anesthesiology and Intensive Care Medicine, University Hospital Giessen, Justus-Liebig-University, Giessen, 3Institute of Medical Biometry and Epidemiology, Philipps University, Marburg, 4Department of Anesthesiology and Intensive Care Medicine, Diakoniekrankenhaus Schwäbisch Hall, Schwäbisch Hall, Germany Background: Nerve blood flow has a critical role in acute and chronic pathologies in peripheral nerves. Influences of local anesthetics and adjuvants on tissue perfusion and oxygenation are deemed as relevant factors for nerve damage after peripheral regional anesthesia. The link between low tissue perfusion due to local anesthetics and resulting tissue oxygenation is unclear.Methods: Combined tissue spectrophotometry and laser-Doppler flowmetry were used to assess nerve blood flow in 40 surgically exposed median nerves in pigs, as well as nerve tissue oximetry for 60 min. After baseline measurements, test solutions saline (S, bupivacaine (Bupi, bupivacaine with epinephrine (BupiEpi, and bupivacaine with clonidine (BupiCloni were applied topically.Results: Bupivacaine resulted in significant decrease in nerve blood flow, as well as tissue oximetry values, compared with saline control. Addition of epinephrine resulted in a rapid, but nonsignificant, reduction of nerve blood flow and extensive lowering of tissue oximetry levels. The use of clonidine resulted in a reduction of nerve blood flow, comparable to bupivacaine alone (relative blood flow at T60 min compared with baseline, S: 0.86 (0.67–1.18, median (25th–75th percentile; Bupi: 0.33 (0.25–0.60; BupiCloni: 0.43 (0.38–0.63; and BupiEpi: 0.41(0.30–0.54. The use of adjuvants did not result in any relevant impairment of tissue oximetry

  8. Bioreactor-based bone tissue engineering: the influence of dynamic flow on osteoblast phenotypic expression and matrix mineralization.

    Science.gov (United States)

    Yu, Xiaojun; Botchwey, Edward A; Levine, Elliot M; Pollack, Solomon R; Laurencin, Cato T

    2004-08-03

    An important issue in tissue engineering concerns the possibility of limited tissue ingrowth in tissue-engineered constructs because of insufficient nutrient transport. We report a dynamic flow culture system using high-aspect-ratio vessel rotating bioreactors and 3D scaffolds for culturing rat calvarial osteoblast cells. 3D scaffolds were designed by mixing lighter-than-water (density, 1g/ml) microspheres of 85:15 poly(lactide-co-glycolide). We quantified the rate of 3D flow through the scaffolds by using a particle-tracking system, and the results suggest that motion trajectories and, therefore, the flow velocity around and through scaffolds in rotating bioreactors can be manipulated by varying the ratio of heavier-than-water to lighter-than-water microspheres. When rat primary calvarial cells were cultured on the scaffolds in bioreactors for 7 days, the 3D dynamic flow environment affected bone cell distribution and enhanced cell phenotypic expression and mineralized matrix synthesis within tissue-engineered constructs compared with static conditions. These studies provide a foundation for exploring the effects of dynamic flow on osteoblast function and provide important insight into the design and optimization of 3D scaffolds suitable in bioreactors for in vitro tissue engineering of bone.

  9. Development of a Semi-Automatic Technique for Flow Estimation using Optical Flow Registration and k-means Clustering on Two Dimensional Cardiovascular Magnetic Resonance Flow Images

    DEFF Research Database (Denmark)

    Brix, Lau; Christoffersen, Christian P. V.; Kristiansen, Martin Søndergaard

    was then categorized into groups by the k-means clustering method. Finally, the cluster containing the vessel under investigation was selected manually by a single mouse click. All calculations were performed on a Nvidia 8800 GTX graphics card using the Compute Unified Device Architecture (CUDA) extension to the C...... promising because it saves time for post-processing. However, the k-means cluster approach is not comprehensive for quantitative flow estimations as it is but seems feasible for a subsequent segmentation algorithm like deformable contours (i.e. snakes). Future work may overcome this manual part and make...... programming language. Results: Seven clusters were created and identification of the one including the aorta was hereafter trivial. However, a part of the rim of the aortic vessel was excluded from the main aortic cluster. Conclusion: The registration and clustering approach for analyzing CMR flow data seems...

  10. The role of tissue oxygen tension in the control of local blood flow in the microcirculation of skeletal muscles

    DEFF Research Database (Denmark)

    Ngo, Thuc Anh

    2010-01-01

    In the microcirculation blood flow is highly regulated dependent on the metabolic activity of the tissues. Among several mechanisms, mechanisms involved in the coupling of changes in tissue oxygen tension due to changes in the metabolic activity of the tissue play an important role. In the systemic...... or high oxygen superfusate. This indicates that adenosine and NO- release are not involved in the regulation of blood flow induced by changes in tissue oxygen tension. The roles of prostaglandins and 20-HETE were also tested. While application of indomethacin (inhibitor of cyclooxygenase...... (inhibitor of KATP channels) in the superfusate abolished both vasodilatation and constriction to low and high oxygen superfusate, indicating that KATP channels are involved in both hypoxic vasodilatation and hyperoxic vasoconstriction. Red blood cells (RBCs) have been proposed to release ATP and...

  11. Blood flow and vascular reactivity in collaterally perfused brain tissue. Evidence of an ischemic penumbra in patients with acute stroke

    DEFF Research Database (Denmark)

    Olsen, T S; Larsen, B; Herning, M

    1983-01-01

    In a group of 48 patients with completed stroke, 8 patients had viable collaterally perfused brain tissue which was accessible for rCBF recordings with a two dimensional technique. All 8 had deep subcortical infarcts on CT-scan, and angiographic occlusion of the arteries normally supplying...... the infarcted territory. The brain tissue overlying the deep infarcts appeared normal on CT-scan and was supplied by collateral circulation. rCBF was measured in all within 72 hours after the stroke. The intra-carotid Xe-133 injection method and a 254 multidetector camera were used to study rCBF. Relatively...... ischemic low flow areas were a constant finding in the collaterally perfused tissue. In 6 of the patients, the collaterally perfused part of the brain had low flow values comparable to those of an "ischemic penumbra" (viable, but functionally depressed brain tissue due to inadequate perfusion...

  12. Human adipose tissue blood flow during prolonged exercise, III. Effect of beta-adrenergic blockade, nicotinic acid and glucose infusion

    DEFF Research Database (Denmark)

    Bülow, J

    1981-01-01

    Subcutaneous adipose tissue blood flow (ATBF) was measured in six male subjects by the 133Xe-washout technique during 3-4 h of exercise at a work load corresponding to an oxygen uptake of about 1.71/min. The measurements were done during control conditions, during blockade of lipolysis by nicotinic...... with the hypothesis that adipose tissue vasodilation during exercise is secondary to metabolic events connected to lipolysis....

  13. The effects of different lying positions on interface pressure, skin temperature, and tissue blood flow in nursing home residents.

    Science.gov (United States)

    Källman, Ulrika; Engström, Maria; Bergstrand, Sara; Ek, Anna-Christina; Fredrikson, Mats; Lindberg, Lars-Göran; Lindgren, Margareta

    2015-03-01

    Although repositioning is considered an important intervention to prevent pressure ulcers, tissue response during loading in different lying positions has not been adequately explored. To compare the effects of different lying positions on interface pressure, skin temperature, and tissue blood flow in nursing home residents. From May 2011 to August 2012, interface pressure, skin temperature, and blood flow at three tissue depths were measured for 1 hr over the sacrum in 30° supine tilt and 0° supine positions and over the trochanter major in 30° lateral and 90° lateral positions in 25 residents aged 65 years or older. Measurement of interface pressure was accomplished using a pneumatic pressure transmitter connected to a digital manometer, skin temperature using a temperature sensor, and blood flow using photoplethysmography and laser Doppler flowmetry. Interface pressure was significantly higher in the 0° supine and 90° lateral positions than in 30° supine tilt and 30° lateral positions. The mean skin temperature increased from baseline in all positions. Blood flow was significantly higher in the 30° supine tilt position compared to the other positions. A hyperemic response in the post pressure period was seen at almost all tissue depths and positions. The 30° supine tilt position generated less interface pressure and allowed greater tissue perfusion, suggesting that this position is the most beneficial. © The Author(s) 2014.

  14. Evaluation of a new high power, wide separation laser Doppler probe: potential measurement of deeper tissue blood flow.

    Science.gov (United States)

    Clough, Geraldine; Chipperfield, Andrew; Byrne, Christopher; de Mul, Frits; Gush, Rodney

    2009-09-01

    To compare the output from a novel high power, wide separation laser Doppler flow probe (DP1-V2-HP, 4 mm, with IRLD20) with that of a standard flow probe (DP1-V2, 0.5 mm, with DRT4) (Moor UK) and to explore its potential for use in the noninvasive measurement of blood flow in deeper tissues in humans. Monte Carlo modeling was used to predict depths of light scattering in skin with each probe, geometry. Experimentally, forearm blood flow was measured at rest and during local warming of the skin surface and post occlusion reactive hyperaemia (PORH). Laser Doppler blood flux (LDF) and the power spectral density of its component frequency intervals, were compared. Monte Carlo modeling indicated that while the majority of wide probe LD signal derives from deeper tissue, a significant portion is from superficial (dermal) tissue (and vice versa for standard probe). Perturbation of local blood flow differentially increased LDF and spectral power as measured by the two probes, with the standard skin probe showing a significantly greater response to local skin warming (p<0.01). These differences support our hypothesis that the wide probe is recording predominantly blood flux within the vasculature of sub-dermal tissue. This is in agreement with Monte Carlo simulation.

  15. Cerebral tissue oxygenation index, cardiac output and superior vena cava flow in infants with birth weight less than 1250 grams in the first 48 hours of life.

    Science.gov (United States)

    Sirc, J; Dempsey, E M; Miletin, J

    2013-07-01

    Near-infrared spectroscopy is a non-invasive method of assessing cerebral oxygenation. Functional echocardiography is increasingly used by neonatologists in the assessment of cardiovascular function. To correlate cerebral tissue oxygenation index (cTOI) and cardiac output in infants less than 1250 g at 6, 12, 24 and 48 hours of age. A prospective observational study. Newborns with birth weightoutputs, ductus arteriosus and cTOI were performed at 6, 12, 24 and 48 hours of age. Clinical parameters, including mean blood pressure, mean airway pressure, blood gas parameters and oxygen saturations were recorded. 22 neonates were enrolled following parental consent. The mean birth weight was 851 g (SD±201), mean gestational age was 25.9 weeks (SD±1.7). Mean SVC flow at 6 hours of age was 56.8 ml/kg/min and increased to 68.6 ml/kg/min at 48 hours of age. 9 infants (41%) had at least one measurement of low SVC flow (output increased during first 48 hours of life. cTOI decreased at 12 hours of age with a concomitant increase in fractionated oxygen extraction. These changes reflect transitional changes in both cardiac and cerebral hemodynamics in extremely low gestational age newborns during the first 48 hours. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. 4D cardiovascular magnetic resonance velocity mapping of alterations of right heart flow patterns and main pulmonary artery hemodynamics in tetralogy of Fallot

    Science.gov (United States)

    2012-01-01

    Background To assess changes in right heart flow and pulmonary artery hemodynamics in patients with repaired Tetralogy of Fallot (rTOF) we used whole heart, four dimensional (4D) velocity mapping (VM) cardiovascular magnetic resonance (CMR). Methods CMR studies were performed in 11 subjects with rTOF (5M/6F; 20.1 ± 12.4 years) and 10 normal volunteers (6M/4F; 34.2 ± 13.4 years) on clinical 1.5T and 3.0T MR scanners. 4D VM-CMR was performed using PC VIPR (Phase Contrast Vastly undersampled Isotropic Projection Reconstruction). Interactive streamline and particle trace visualizations of the superior and inferior vena cava (IVC and SVC, respectively), right atrium (RA), right ventricle (RV), and pulmonary artery (PA) were generated and reviewed by three experienced readers. Main PA net flow, retrograde flow, peak flow, time-to-peak flow, peak acceleration, resistance index and mean wall shear stress were quantified. Differences in flow patterns between the two groups were tested using Fisher's exact test. Differences in quantitative parameters were analyzed with the Kruskal-Wallis rank sum test. Results 4D VM-CMR was successfully performed in all volunteers and subjects with TOF. Right heart flow patterns in rTOF subjects were characterized by (a) greater SVC/IVC flow during diastole than systole, (b) increased vortical flow patterns in the RA and in the RV during diastole, and (c) increased helical or vortical flow features in the PA's. Differences in main PA retrograde flow, resistance index, peak flow, time-to-peak flow, peak acceleration and mean wall shear stress were statistically significant. Conclusions Whole heart 4D VM-CMR with PC VIPR enables detection of both normal and abnormal right heart flow patterns, which may allow for comprehensive studies to evaluate interdependencies of post-surgically altered geometries and hemodynamics. PMID:22313680

  17. Cerebral blood flow, blood volume, and brain tissue hematocrit during isovolemic hemodilution with hetastarch in rats.

    Science.gov (United States)

    Todd, M M; Weeks, J B; Warner, D S

    1992-07-01

    The influence of isovolemic hemodilution with 6% hetastarch [hematocrits (Hct) ranging from 43 to 20%] on cerebral blood flow (CBF), cerebral red blood cell and plasma volumes, total cerebral blood volume (CBV), and cerebral Hct was examined in normothermic, normocarbic, halothane-anesthetized Sprague-Dawley rats. CBF was measured via the indicator-fractionation method ([3H]nicotine), red blood cell volume was measured using 99mTc-labeled red blood cells, while plasma volume was measured using [14C]dextran. Brain tissue was fixed in situ by microwave irradiation. All data plots (e.g., CBF vs. Hct) were fitted by linear regression methods. Hemodilution was associated with a progressive increase in forebrain CBF (from a fitted value of 78 ml.100 g-1.min-1 at Hct = 43%, to 171 ml.100 g-1.min-1 at 20%). Cerebral plasma volume also rose, while red blood cell volume decreased. Total CBV (i.e., the sum of red blood cell and plasma volumes) increased in parallel with CBF (from 2.51 ml/100 g at Hct = 43 to 4.94 ml/100 g at Hct = 20%). This increase is larger than can be explained by a simple increase in the diameter of arterial/arteriolar resistance vessels and may be due to either capillary recruitment or to an increase in the volume of postarteriolar structures. Calculated cerebral tissue hematocrit decreased. The magnitude of this decrease was larger than the reduction in arterial Hct; the ratio of cerebral to arterial Hct decreased from 0.780 at an arterial Hct equaling 43% to 0.458 at Hct equaling 20%.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Acute effects of sildenafil on flow mediated dilatation and cardiovascular autonomic nerve function in type 2 diabetic patients.

    Science.gov (United States)

    Stirban, Alin; Laude, Dominique; Elghozi, Jean-Luc; Sander, Denise; Agelink, Marcus W; Hilz, Max J; Ziegler, Dan

    2009-02-01

    Sildenafil, frequently used as on demand medication for the treatment of erectile dysfunction (ED), has been suggested to improve endothelial function but also to alter blood pressure (BP) and induce sympathetic activation. In people with type 2 diabetes mellitus (T2DM), a high-risk population, the safety profile and the effects on endothelial function of a maximal sildenafil dose (100 mg) have not been investigated and therefore constituted the aim of our study. A double-blind, placebo-controlled, cross-over trial using a single dose of 100 mg sildenafil or placebo has been conducted in 40 subjects with T2DM without known CVD. Haemodynamic parameters, flow mediated dilatation (FMD) in brachial artery, cardiovascular autonomic function tests and spontaneous baroreflex sensitivity (BRS) were measured. Sixty minutes after administration of sildenafil but not placebo, a fall of supine systolic blood pressure (SBP) (-5.41 +/- 1.87 vs. + 0.54 +/- 1.71 mmHg) and diastolic blood pressure (DBP) (-4.46 +/- 1.13 vs. + 0.89 +/- 0.94 mmHg), as well as orthostatic SBP (-7.41 +/- 2.35 vs. + 0.94 +/- 2.06 mmHg) and DBP (-5.65 +/- 1.45 vs. + 1.76 +/- 1.00 mmHg) during standing occurred, accompanied by an increase in heart rate (+1.98 +/- 0.69 vs. - 2.42 +/- 0.59 beats/min) (all p < 0.01 vs. placebo). Changes in BP to standing up, FMD, time domain and frequency domain indices of heart rate variability (HRV) and BRS were comparable between sildenafil and placebo. Sildenafil administered at a maximum single dose to T2DM men results in a mild increase in heart rate and decrease in BP, but it induces neither an acute improvement of FMD nor any adverse effects on orthostatic BP regulation, HRV and BRS. Copyright (c) 2008 John Wiley & Sons, Ltd.

  19. Regional disturbances in blood flow and metabolism in equine limb wound healing with formation of exuberant granulation tissue

    DEFF Research Database (Denmark)

    Sørensen, Mette A.; Petersen, Lars; Bundgaard, Louise

    2014-01-01

    As in other fibroproliferative disorders, hypoxia has been suggested to play a key role in the pathogenesis of exuberant granulation tissue (EGT). The purpose of this study was to investigate metabolism and blood flow locally in full-thickness wounds healing with (limb wounds) and without (body w...

  20. A Nth-order linear algorithm for extracting diffuse correlation spectroscopy blood flow indices in heterogeneous tissues

    Energy Technology Data Exchange (ETDEWEB)

    Shang, Yu; Yu, Guoqiang, E-mail: guoqiang.yu@uky.edu [Department of Biomedical Engineering, University of Kentucky, Lexington, Kentucky 40506 (United States)

    2014-09-29

    Conventional semi-infinite analytical solutions of correlation diffusion equation may lead to errors when calculating blood flow index (BFI) from diffuse correlation spectroscopy (DCS) measurements in tissues with irregular geometries. Very recently, we created an algorithm integrating a Nth-order linear model of autocorrelation function with the Monte Carlo simulation of photon migrations in homogenous tissues with arbitrary geometries for extraction of BFI (i.e., αD{sub B}). The purpose of this study is to extend the capability of the Nth-order linear algorithm for extracting BFI in heterogeneous tissues with arbitrary geometries. The previous linear algorithm was modified to extract BFIs in different types of tissues simultaneously through utilizing DCS data at multiple source-detector separations. We compared the proposed linear algorithm with the semi-infinite homogenous solution in a computer model of adult head with heterogeneous tissue layers of scalp, skull, cerebrospinal fluid, and brain. To test the capability of the linear algorithm for extracting relative changes of cerebral blood flow (rCBF) in deep brain, we assigned ten levels of αD{sub B} in the brain layer with a step decrement of 10% while maintaining αD{sub B} values constant in other layers. Simulation results demonstrate the accuracy (errors < 3%) of high-order (N ≥ 5) linear algorithm in extracting BFIs in different tissue layers and rCBF in deep brain. By contrast, the semi-infinite homogenous solution resulted in substantial errors in rCBF (34.5% ≤ errors ≤ 60.2%) and BFIs in different layers. The Nth-order linear model simplifies data analysis, thus allowing for online data processing and displaying. Future study will test this linear algorithm in heterogeneous tissues with different levels of blood flow variations and noises.

  1. In-Situ Characterization of Tissue Blood Flow, Blood Content, and Water State Using New Techniques in Magnetic Resonance Imaging.

    Science.gov (United States)

    Conturo, Thomas Edward

    Tissue blood flow, blood content, and water state have been characterized in-situ with new nuclear magnetic resonance imaging techniques. The sensitivities of standard techniques to the physiologic tissue parameters spin density (N_{rm r}) and relaxation times (T_1 and T_2 ) are mathematically defined. A new driven inversion method is developed so that tissue T_1 and T_2 changes produce cooperative intensity changes, yielding high contrast, high signal to noise, and sensitivity to a wider range of tissue parameters. The actual tissue parameters were imaged by automated collection of multiple-echo data having multiple T _1 dependence. Data are simultaneously fit by three-parameters to a closed-form expression, producing lower inter-parameter correlation and parameter noise than in separate T_1 or T_2 methods or pre-averaged methods. Accurate parameters are obtained at different field strengths. Parametric images of pathology demonstrate high sensitivity to tissue heterogeneity, and water content is determined in many tissues. Erythrocytes were paramagnetically labeled to study blood content and relaxation mechanisms. Liver and spleen relaxation were enhanced following 10% exchange of animal blood volumes. Rapid water exchange between intracellular and extracellular compartments was validated. Erythrocytes occupied 12.5% of renal cortex volume, and blood content was uniform in the liver, spleen and kidney. The magnitude and direction of flow velocity was then imaged. To eliminate directional artifacts, a bipolar gradient technique sensitized to flow in different directions was developed. Phase angle was reconstructed instead of intensity since the former has a 2pi -fold higher dynamic range. Images of flow through curves demonstrated secondary flow with a centrifugally-biased laminar profile and stationary velocity peaks along the curvature. Portal vein flow velocities were diminished or reversed in cirrhosis. Image artifacts have been characterized and removed. The

  2. Effect of cocoa/chocolate ingestion on brachial artery flow-mediated dilation and its relevance to cardiovascular health and disease in humans.

    Science.gov (United States)

    Monahan, Kevin D

    2012-11-15

    Prospective studies indicate that high intake of dietary flavanols, such as those contained in cocoa/chocolate, are associated with reduced rates of cardiovascular-related morbidity and mortality in humans. Numerous mechanisms may underlie these associations such as favorable effects of flavanols on blood pressure, platelet aggregation, thrombosis, inflammation, and the vascular endothelium. The brachial artery flow-mediated dilation (FMD) technique has emerged as a robust method to quantify endothelial function in humans. Collectively, the preponderance of evidence indicates that FMD is a powerful surrogate measure for firm cardiovascular endpoints, such as cardiovascular-related mortality, in humans. Thus, literally thousands of studies have utilized this technique to document group differences in FMD, as well as to assess the effects of various interventions on FMD. In regards to the latter, numerous studies indicate that both acute and chronic ingestion of cocoa/chocolate increases FMD in humans. Increases in FMD after cocoa/chocolate ingestion appear to be dose-dependent such that greater increases in FMD are observed after ingestion of larger quantities. The mechanisms underlying these responses are likely diverse, however most data suggest an effect of increased nitric oxide bioavailability. Thus, positive vascular effects of cocoa/chocolate on the endothelium may underlie (i.e., be linked mechanistically to) reductions in cardiovascular risk in humans. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Evaluating the hemodynamical response of a cardiovascular system under support of a continuous flow left ventricular assist device via numerical modeling and simulations.

    Science.gov (United States)

    Bozkurt, Selim; Safak, Koray K

    2013-01-01

    Dilated cardiomyopathy is the most common type of the heart failure which can be characterized by impaired ventricular contractility. Mechanical circulatory support devices were introduced into practice for the heart failure patients to bridge the time between the decision to transplant and the actual transplantation which is not sufficient due to the state of donor organ supply. In this study, the hemodynamic response of a cardiovascular system that includes a dilated cardiomyopathic heart under support of a newly developed continuous flow left ventricular assist device--Heart Turcica Axial--was evaluated employing computer simulations. For the evaluation, a numerical model which describes the pressure-flow rate relations of Heart Turcica Axial, a cardiovascular system model describing the healthy and pathological hemodynamics, and a baroreflex model regulating the heart rate were used. Heart Turcica Axial was operated between 8000 rpm and 11,000 rpm speeds with 1000 rpm increments for assessing the pump performance and response of the cardiovascular system. The results also give an insight about the range of the possible operating speeds of Heart Turcica Axial in a clinical application. Based on the findings, operating speed of Heart Turcica Axial should be between 10,000 rpm and 11,000 rpm.

  4. Evaluating the Hemodynamical Response of a Cardiovascular System under Support of a Continuous Flow Left Ventricular Assist Device via Numerical Modeling and Simulations

    Science.gov (United States)

    Safak, Koray K.

    2013-01-01

    Dilated cardiomyopathy is the most common type of the heart failure which can be characterized by impaired ventricular contractility. Mechanical circulatory support devices were introduced into practice for the heart failure patients to bridge the time between the decision to transplant and the actual transplantation which is not sufficient due to the state of donor organ supply. In this study, the hemodynamic response of a cardiovascular system that includes a dilated cardiomyopathic heart under support of a newly developed continuous flow left ventricular assist device—Heart Turcica Axial—was evaluated employing computer simulations. For the evaluation, a numerical model which describes the pressure-flow rate relations of Heart Turcica Axial, a cardiovascular system model describing the healthy and pathological hemodynamics, and a baroreflex model regulating the heart rate were used. Heart Turcica Axial was operated between 8000 rpm and 11000 rpm speeds with 1000 rpm increments for assessing the pump performance and response of the cardiovascular system. The results also give an insight about the range of the possible operating speeds of Heart Turcica Axial in a clinical application. Based on the findings, operating speed of Heart Turcica Axial should be between 10000 rpm and 11000 rpm. PMID:24363780

  5. Two-dimensional real-time blood flow and temperature of soft tissue around maxillary anterior implants.

    Science.gov (United States)

    Nakamoto, Tetsuji; Kanao, Masato; Kondo, Yusuke; Kajiwara, Norihiro; Masaki, Chihiro; Takahashi, Tetsu; Hosokawa, Ryuji

    2012-12-01

    The aims of this study were to (1) evaluate the basic nature of soft tissue surrounding maxillary anterior implants by simultaneous measurements of blood flow and surface temperature and (2) analyze differences with and without bone grafting associated with implant placement to try to detect the signs of surface morphology change. Twenty maxillary anterior implant patients, 10 bone grafting and 10 graftless, were involved in this clinical trial. Soft tissue around the implant was evaluated with 2-dimensional laser speckle imaging and a thermograph. Blood flow was significantly lower in attached gingiva surrounding implants in graftless patients (P = 0.0468). On the other hand, it was significantly lower in dental papillae (P = 0.0254), free gingiva (P = 0.0198), and attached gingiva (P = 0.00805) in bone graft patients. Temperature was significantly higher in free gingiva (P = 0.00819) and attached gingiva (P = 0.00593) in graftless patients, whereas it was significantly higher in dental papilla and free gingiva in implants with bone grafting. The results suggest that simultaneous measurements of soft-tissue blood flow and temperature is a useful technique to evaluate the microcirculation of soft tissue surrounding implants.

  6. Balanced high fat diet reduces cardiovascular risk in obese women although changes in adipose tissue, lipoproteins, and insulin resistance differ by race.

    Science.gov (United States)

    Niswender, Kevin D; Fazio, Sergio; Gower, Barbara A; Silver, Heidi J

    2018-05-01

    We previously reported that consuming a balanced high fat diet (BHFD) wherein total saturated fat was reduced and total unsaturated fat increased by proportionately balancing the type of fat (1/3 saturated, 1/3 monounsaturated, 1/3 polyunsaturated) led to significant improvements in inflammatory burden, blood pressure, and vascular function in obese premenopausal European American (EA) and African American (AA) women. Here we compared changes in adipose tissue, lipoproteins, insulin resistance, and cardiovascular risk between EA and AA women. Dietary intakes, plasma fatty acids, lipids, apolipoproteins, lipoproteins, HOMA-IR and ASCVD risk was measured in 144 women who consumed BHFD for 16 weeks. Generalized linear modeling was performed while controlling for change in body weight. EA women had greater reductions in visceral adipose tissue. Only EA women had significant reductions in fasting insulin levels (↓24.8%) and HOMA-IR (↓29%) scores. In EA women, the most significant improvements occurred in VLDL particle size (↑), apolipoprotein B levels (↑), serum TG (↓), number of plasma LDL particles (↓), and serum LDL-cholesterol (↓). In AA women, significant improvements occurred in HDL particle size (↑), number of large HDL particles (↑), and apolipoprotein AI levels (↑). Consequently, both groups had improved ASCVD risk scores (↓5.5%). Consuming the balanced high fat diet led to significant reduction in cardiovascular risk factors in both groups. However, the pattern of response to BHFD differed with EA women responding more in components of the apolipoprotein B pathway versus AA women responding more in components of the apolipoprotein AI pathway. Published by Elsevier Inc.

  7. Cerebral tissue oxygenation index and superior vena cava blood flow in the very low birth weight infant.

    LENUS (Irish Health Repository)

    Moran, M

    2012-02-01

    BACKGROUND: Superior vena cava (SVC) flow assesses blood flow from the upper body, including the brain. Near infrared spectroscopy (NIRS) provides information on brain perfusion and oxygenation. AIM: To assess the relationship between cerebral tissue oxygenation index (cTOI) and cardiac output measures in the very low birth weight (VLBW) infant in the first day of life. METHODS: A prospective observational cohort study. Neonates with birth weight less than 1500 g (VLBW) were eligible for enrollment. Newborns with congenital heart disease, major congenital malformations and greater than Papile grade1 Intraventricular Haemorrhage on day 1 of life were excluded. Echocardiographic evaluation of SVC flow was performed in the first 24 h of life. Low SVC flow states were defined as a flow less than 40 mL\\/kg\\/min. cTOI was measured using NIRO 200 Hamamatsu. RESULTS: Twenty-seven VLBW neonates had both echocardiography and NIRS performed. The median (range) gestation was 29\\/40 (25 + 3 to 31 + 5 weeks) and median birth weight was 1.2 kg (0.57-1.48 kg). The mean (SD) TOI was 68.1 (7.9)%. The mean (SD) SVC flow was 70.36(39.5) mLs\\/kg\\/min. The correlation coefficient of cerebral tissue oxygenation and SVC flow was r = 0.53, p-value 0.005. There was a poor correlation between right and left ventricular output and cTOI which is not surprising considering the influence of intra- and extracardiac shunts. CONCLUSION: There is a positive relationship between cerebral TOI values and SVC flow in the very low birth infant on day one of life.

  8. The importance of bicarbonate and nonbicarbonate buffer systems in batch and continuous flow bioreactors for articular cartilage tissue engineering.

    Science.gov (United States)

    Khan, Aasma A; Surrao, Denver C

    2012-05-01

    In cartilage tissue engineering an optimized culture system, maintaining an appropriate extracellular environment (e.g., pH of media), can increase cell proliferation and extracellular matrix (ECM) accumulation. We have previously reported on a continuous-flow bioreactor that improves tissue growth by supplying the cells with a near infinite supply of medium. Previous studies have observed that acidic environments reduce ECM synthesis and chondrocyte proliferation. Hence, in this study we investigated the combined effects of a continuous culture system (bioreactor) together with additional buffering agents (e.g., sodium bicarbonate [NaHCO₃]) on cartilaginous tissue growth in vitro. Isolated bovine chondrocytes were grown in three-dimensional cultures, either in static conditions or in a continuous-flow bioreactor, in media with or without NaHCO₃. Tissue constructs cultivated in the bioreactor with NaHCO₃-supplemented media were characterized with significantly increased (p<0.05) ECM accumulation (glycosaminoglycans a 98-fold increase; collagen a 25-fold increase) and a 13-fold increase in cell proliferation, in comparison with static cultures. Additionally, constructs grown in the bioreactor with NaHCO₃-supplemented media were significantly thicker than all other constructs (p<0.05). Further, the chondrocytes from the primary construct expanded and synthesized ECM, forming a secondary construct without a separate expansion phase, with a diameter and thickness of 4 mm and 0.72 mm respectively. Tissue outgrowth was negligible in all other culturing conditions. Thus this study demonstrates the advantage of employing a continuous flow bioreactor coupled with NaHCO₃ supplemented media for articular cartilage tissue engineering.

  9. Prioritizing blood flow: cardiovascular performance in response to the competing demands of locomotion and digestion for the Burmese python, Python molurus.

    Science.gov (United States)

    Secor, Stephen M; White, Scott E

    2010-01-01

    Individually, the metabolic demands of digestion or movement can be fully supported by elevations in cardiovascular performance, but when occurring simultaneously, vascular perfusion may have to be prioritized to either the gut or skeletal muscles. Burmese pythons (Python molurus) experience similar increases in metabolic rate during the digestion of a meal as they do while crawling, hence each would have an equal demand for vascular supply when these two actions are combined. To determine, for the Burmese python, whether blood flow is prioritized when snakes are digesting and moving, we examined changes in cardiac performance and blood flow in response to digestion, movement, and the combination of digestion and movement. We used perivascular blood flow probes to measure blood flow through the left carotid artery, dorsal aorta, superior mesenteric artery and hepatic portal vein, and to calculate cardiac output, heart rate and stroke volume. Fasted pythons while crawling experienced a 2.7- and 3.3-fold increase, respectively, in heart rate and cardiac output, and a 66% decrease in superior mesenteric flow. During the digestion of a rodent meal equaling in mass to 24.7% of the snake's body mass, heart rate and cardiac output increased by 3.3- and 4.4-fold, respectively. Digestion also resulted in respective 11.6- and 14.1-fold increases in superior mesenteric and hepatic portal flow. When crawling while digesting, cardiac output and dorsal aorta flow increased by only 21% and 9%, respectively, a modest increase compared with that when they start to crawl on an empty stomach. Crawling did triggered a significant reduction in blood flow to the digesting gut, decreasing superior mesenteric and hepatic portal flow by 81% and 47%, respectively. When faced with the dual demands of digestion and crawling, Burmese pythons prioritize blood flow, apparently diverting visceral supply to the axial muscles.

  10. Comparative Analysis of Cardiovascular Development Related Genes in Stem Cells Isolated from Deciduous Pulp and Adipose Tissue

    Directory of Open Access Journals (Sweden)

    Zhang Xin Loo

    2014-01-01

    Full Text Available Human exfoliated deciduous teeth (SHED and adipose stem cells (ASC were suggested as alternative cell choice for cardiac regeneration. However, the true functionability of these cells toward cardiac regeneration is yet to be discovered. Hence, this study was carried out to investigate the innate biological properties of these cell sources toward cardiac regeneration. Both cells exhibited indistinguishable MSCs characteristics. Human stem cell transcription factor arrays were used to screen expression levels in SHED and ASC. Upregulated expression of transcription factor (TF genes was detected in both sources. An almost equal percentage of > 2-fold changes were observed. These TF genes fall under several cardiovascular categories with higher expressions which were observed in growth and development of blood vessel, angiogenesis, and vasculogenesis categories. Further induction into cardiomyocyte revealed ASC to express more significantly cardiomyocyte specific markers compared to SHED during the differentiation course evidenced by morphology and gene expression profile. Despite this, spontaneous cellular beating was not detected in both cell lines. Taken together, our data suggest that despite being defined as MSCs, both ASC and SHED behave differently when they were cultured in a same cardiomyocytes culture condition. Hence, vigorous characterization is needed before introducing any cell for treating targeted diseases.

  11. Adrenomedullin and cardiovascular diseases

    OpenAIRE

    Wong, Hoi Kin; Cheung, Tommy Tsang; Cheung, Bernard M Y

    2012-01-01

    Summary The cardiovascular system is regulated by the autonomic nervous system, the renin–angiotensin–aldosterone system, nitric oxide (NO) and other factors including neuropeptides. Research in neurohumoral factors has led to the development of many cardiovascular drugs. Adrenomedullin (ADM), initially isolated from the adrenal gland, has diverse physiological and pathophysiological functions in the cardiovascular system. It is produced in many organs and tissues including the vasculature. A...

  12. Transplantation of Normal Adipose Tissue Improves Blood Flow and Reduces Inflammation in High Fat Fed Mice With Hindlimb Ischemia

    Directory of Open Access Journals (Sweden)

    Liyuan Chen

    2018-03-01

    Full Text Available Background: Fat deposition is associated with peripheral arterial disease. Adipose tissue has recently been implicated in vascular remodeling and angiogenic activity. We hypothesized that the transplantation of adipose tissues from normal mice improves blood flow perfusion and neovascularization in high-fat diet fed mice.Methods: After 14 weeks of high-fat diet (HFD-fed mice, unilateral hind limb ischemia was performed. Subcutaneous white adipose tissue (WAT and brown adipose tissue (BAT fat pads were harvested from normal EGFP mice, and subcutaneously transplanted over the region of the adductor muscles of HFD mice. Blood flow was measured using Laser Doppler Scanner. Vascular density, macrophages infiltration, and macrophage polarization were examined by RT-qPCR, and immunohistochemistry.Results: We found that the transplantation of WAT derived from normal mice improved functional blood flow in HFD-fed mice compared to mice transplanted with BAT and sham-treated mice. WAT transplantation increased the recruitment of pericytes associated with nascent blood vessels, but did not affect capillary formation. Furthermore, transplantation of WAT ameliorated HFD-induced insulin resistance, M2 macrophage predominance and the release of arteriogenic factors in ischemic muscles. Mice receiving WAT also displayed a marked reduction in several proinflammatory cytokines. In contrast, mice transplanted with BAT were glucose intolerant and demonstrated increased IL-6 levels in ischemic muscles.Conclusion: These results indicate that transplantation of adipose tissue elicits improvements in blood perfusion and beneficial effects on systemic glucose homeostasis and could be a promising therapeutic option for the treatment of diabetic peripheral arterial disease.

  13. A Protocol for the Comprehensive Flow Cytometric Analysis of Immune Cells in Normal and Inflamed Murine Non-Lymphoid Tissues

    Science.gov (United States)

    Yu, Yen-Rei A.; O’Koren, Emily G.; Hotten, Danielle F.; Kan, Matthew J.; Kopin, David; Nelson, Erik R.; Que, Loretta; Gunn, Michael D.

    2016-01-01

    Flow cytometry is used extensively to examine immune cells in non-lymphoid tissues. However, a method of flow cytometric analysis that is both comprehensive and widely applicable has not been described. We developed a protocol for the flow cytometric analysis of non-lymphoid tissues, including methods of tissue preparation, a 10-fluorochrome panel for cell staining, and a standardized gating strategy, that allows the simultaneous identification and quantification of all major immune cell types in a variety of normal and inflamed non-lymphoid tissues. We demonstrate that our basic protocol minimizes cell loss, reliably distinguishes macrophages from dendritic cells (DC), and identifies all major granulocytic and mononuclear phagocytic cell types. This protocol is able to accurately quantify 11 distinct immune cell types, including T cells, B cells, NK cells, neutrophils, eosinophils, inflammatory monocytes, resident monocytes, alveolar macrophages, resident/interstitial macrophages, CD11b- DC, and CD11b+ DC, in normal lung, heart, liver, kidney, intestine, skin, eyes, and mammary gland. We also characterized the expression patterns of several commonly used myeloid and macrophage markers. This basic protocol can be expanded to identify additional cell types such as mast cells, basophils, and plasmacytoid DC, or perform detailed phenotyping of specific cell types. In examining models of primary and metastatic mammary tumors, this protocol allowed the identification of several distinct tumor associated macrophage phenotypes, the appearance of which was highly specific to individual tumor cell lines. This protocol provides a valuable tool to examine immune cell repertoires and follow immune responses in a wide variety of tissues and experimental conditions. PMID:26938654

  14. A Protocol for the Comprehensive Flow Cytometric Analysis of Immune Cells in Normal and Inflamed Murine Non-Lymphoid Tissues.

    Directory of Open Access Journals (Sweden)

    Yen-Rei A Yu

    Full Text Available Flow cytometry is used extensively to examine immune cells in non-lymphoid tissues. However, a method of flow cytometric analysis that is both comprehensive and widely applicable has not been described. We developed a protocol for the flow cytometric analysis of non-lymphoid tissues, including methods of tissue preparation, a 10-fluorochrome panel for cell staining, and a standardized gating strategy, that allows the simultaneous identification and quantification of all major immune cell types in a variety of normal and inflamed non-lymphoid tissues. We demonstrate that our basic protocol minimizes cell loss, reliably distinguishes macrophages from dendritic cells (DC, and identifies all major granulocytic and mononuclear phagocytic cell types. This protocol is able to accurately quantify 11 distinct immune cell types, including T cells, B cells, NK cells, neutrophils, eosinophils, inflammatory monocytes, resident monocytes, alveolar macrophages, resident/interstitial macrophages, CD11b- DC, and CD11b+ DC, in normal lung, heart, liver, kidney, intestine, skin, eyes, and mammary gland. We also characterized the expression patterns of several commonly used myeloid and macrophage markers. This basic protocol can be expanded to identify additional cell types such as mast cells, basophils, and plasmacytoid DC, or perform detailed phenotyping of specific cell types. In examining models of primary and metastatic mammary tumors, this protocol allowed the identification of several distinct tumor associated macrophage phenotypes, the appearance of which was highly specific to individual tumor cell lines. This protocol provides a valuable tool to examine immune cell repertoires and follow immune responses in a wide variety of tissues and experimental conditions.

  15. Soluble CD54 induces human endothelial cells ex vivo expansion useful for cardiovascular regeneration and tissue engineering application

    KAUST Repository

    Malara, N.M.

    2015-03-01

    Aim: Consistent expansion of primary human endothelial cells in vitro is critical in the development of engineered tissue. A variety of complex culture media and techniques developed from different basal media have been reported with alternate success. Incongruous results are further confounded by donor-to-donor variability and cellular source of derivation. Our results demonstrate how to overcome these limitations using soluble CD54 (sCD54) as additive to conventional culture medium. Methods and results: Isolated primary fragment of different vessel types was expanded in Ham\\'s F12 DMEM, enriched with growth factors, Fetal Calf Serum and conditioned medium of Human Umbilical Vein Endothelial Cells (HUVEC) collected at different passages. Cytokine content of culture media was analyzed in order to identify the soluble factors correlating with better proliferation profile. sCD54 was found to induce the in vitro expansion of human endothelial cells (HECs) independently from the vessels source and even in the absence of HUVEC-conditioned medium. The HECs cultivated in the presence of sCD54 (50 ng/ml), resulted positive for the expression of CD146 and negative for CD45, and lower fibroblast contamination. Cells were capable to proliferate with an S phase of 25%, to produce vascular endothelial growth factor, VEGF, (10 ng/ml) and to give origin to vessel-like tubule in vitro. Conclusion: Our results demonstrate that sCD54 is an essential factor for the in-vitro expansion of HECs without donor and vessel-source variability. Resulting primary cultures can be useful, for tissue engineering in regenerative medicine (e.g. artificial micro tissue generation, coating artificial heart valve etc.) and bio-nanotechnology applications. © 2015 The Authors. Published by Elsevier Ireland Ltd.

  16. Acute effects of nicotine and smoking on blood flow, tissue oxygen, and aerobe metabolism of the skin and subcutis

    DEFF Research Database (Denmark)

    Sørensen, Lars Tue; Jørgensen, Stig; Petersen, Lars J

    2009-01-01

    BACKGROUND: Nicotine released from tobacco smoke causing reduction in blood flow has been suggested as causative for postoperative wound complications in smokers, but the mechanism remains unknown. MATERIALS AND METHODS: In eight healthy male smokers and eight ex-smokers, the cutaneous and subcut......BACKGROUND: Nicotine released from tobacco smoke causing reduction in blood flow has been suggested as causative for postoperative wound complications in smokers, but the mechanism remains unknown. MATERIALS AND METHODS: In eight healthy male smokers and eight ex-smokers, the cutaneous...... and subcutaneous blood flow (QBF, SqBF) was assessed by Laser Doppler and 133Xe clearance. Tissue oxygen tension (TO(2)) was measured by a LICOX O(2)-electrode. Tissue glucose and lactate (Tgluc, Tlact) were assessed by microdialysis. The parameters were studied after intravenous infusion of 1.0 mg nicotine......, smoking of one cigarette, arterial occlusion, and reperfusion. RESULTS: Nicotine infusion decreased SqBF from 4.2 +/- 2.0 to 3.1 +/- 1.2 mL/100 g tissue/min (P

  17. Investigating tissue respiration and skin microhaemocirculation under adaptive changes and the synchronization of blood flow and oxygen saturation rhythms

    International Nuclear Information System (INIS)

    Dunaev, A V; Palmer, S G; Stewart, N A; Sokolovski, S G; Rafailov, E U; Sidorov, V V; Krupatkin, A I; Rafailov, I E

    2014-01-01

    Multi-functional laser non-invasive diagnostic systems allow the study of a number of microcirculatory parameters, including index of blood microcirculation (I m ) (by laser Doppler flowmetry, LDF) and oxygen saturation (S t O 2 ) of skin tissue (by tissue reflectance oximetry, TRO). This research aimed to use such a system to investigate the synchronization of microvascular blood flow and oxygen saturation rhythms under normal and adaptive change conditions. Studies were conducted on eight healthy volunteers of 21–49 years. These volunteers were observed between one and six months, totalling 422 basic tests (3 min each). Measurements were performed on the palmar surface of the right middle finger and the lower forearm's medial surface. Rhythmic oscillations of LDF and TRO were studied using wavelet analysis. Combined tissue oxygen consumption data for all volunteers during ‘adaptive changes’ increased relative to normal conditions with and without arteriovenous anastomoses. Data analysis revealed resonance and synchronized rhythms in microvascular blood flow and oxygen saturation as an adaptive change in myogenic oscillation (vasomotion) resulting from exercise and possibly psychoemotional stress. Synchronization of myogenic rhythms during adaptive changes may lead to increased oxygen consumption as a result of increased microvascular blood flow velocity. (paper)

  18. Localization of microfibrillar-associated protein 4 (MFAP4 in human tissues: clinical evaluation of serum MFAP4 and its association with various cardiovascular conditions.

    Directory of Open Access Journals (Sweden)

    Helle Wulf-Johansson

    Full Text Available Microfibrillar-associated protein 4 (MFAP4 is located in the extracellular matrix (ECM. We sought to identify tissues with high levels of MFAP4 mRNA and MFAP4 protein expression. Moreover, we aimed to evaluate the significance of MFAP4 as a marker of cardiovascular disease (CVD and to correlate MFAP4 with other known ECM markers, such as fibulin-1, osteoprotegerin (OPG, and osteopontin (OPN. Quantitative real-time PCR demonstrated that MFAP4 mRNA was more highly expressed in the heart, lung, and intestine than in other elastic tissues. Immunohistochemical studies demonstrated high levels of MFAP4 protein mainly at sites rich in elastic fibers and within blood vessels in all tissues investigated. The AlphaLISA technique was used to determine serum MFAP4 levels in a clinical cohort of 172 patients consisting of 5 matched groups with varying degrees of CVD: 1: patients with ST elevation myocardial infarction (STEMI, 2: patients with non-STEMI, 3: patients destined for vascular surgery because of various atherosclerotic diseases (stable atherosclerotic disease, 4: apparently healthy individuals with documented coronary artery calcification (CAC-positive, and 5: apparently healthy individuals without signs of coronary artery calcification (CAC-negative. Serum MFAP4 levels were significantly lower in patients with stable atherosclerotic disease than CAC-negative individuals (p<0.05. Furthermore, lower serum MFAP4 levels were present in patients with stable atherosclerotic disease compared with STEMI and non-STEMI patients (p<0.05. In patients with stable atherosclerotic disease, positive correlations between MFAP4 and both fibulin-1 (ρ = 0.50; p = 0.0244 and OPG (ρ = 0.62; p = 0.0014 were found. Together, these results indicate that MFAP4 is mainly located in elastic fibers and is highly expressed in blood vessels. The present study suggests that serum MFAP4 varies in groups of patients with different cardiovascular conditions

  19. Effect of insulin catheter wear-time on subcutaneous adipose tissue blood flow and insulin absorption in humans

    DEFF Research Database (Denmark)

    Clausen, Trine Schnedler; Kaastrup, Peter; Stallknecht, Bente

    2009-01-01

    .1 +/- 0.7 kg/m(2)) and connected to an insulin pump delivering a constant rate of isotonic saline for 4 days. Subjects participated in four study days (days 0, 1, 2, and 4) during which ATBF around the catheter tip was measured by (133)Xe clearance and absorption of an insulin aspart bolus (0.1 U......BACKGROUND: Insertion of an insulin catheter for continuous subcutaneous insulin infusion into the subcutaneous adipose tissue (SAT) causes a tissue trauma that may have consequences for insulin absorption. We evaluated the importance of insulin catheter wear-time on subcutaneous adipose tissue...... blood flow (ATBF) and absorption of the rapid-acting insulin analog insulin aspart over a period of 4 days. METHODS: Teflon insulin catheters (Medtronic, Minneapolis, MN) were inserted into the abdominal SAT of 10 healthy men without diabetes (mean +/- SEM age, 23.0 +/- 1.1 years; body mass index, 22...

  20. Are blood flow and lipolysis in subcutaneous adipose tissue influenced by contractions in adjacent muscles in humans?

    DEFF Research Database (Denmark)

    Stallknecht, Bente; Dela, Flemming; Helge, Jørn Wulff

    2006-01-01

    Aerobic exercise increases whole body adipose tissue lipolysis, but is lipolysis higher in subcutaneous adipose tissue (SCAT) adjacent to contracting muscles than in SCAT adjacent to resting muscles? Ten healthy, overnight-fasted males performed one-legged knee extension exercise at 25% of maximal...... workload (W(max)) for 30 min followed by exercise at 55% W(max) for 120 min with the other leg and finally exercised at 85% W(max) for 30 min with the first leg. Subjects rested for 30 min between exercise periods. Femoral SCAT blood flow was estimated from washout of (133)Xe, and lipolysis was calculated...... from femoral SCAT interstitial and arterial glycerol concentrations and blood flow. In general, blood flow and lipolysis were higher in femoral SCAT adjacent to contracting than adjacent to resting muscle (time 15-30 min; blood flow: 25% W(max) 6.6 +/- 1.0 vs. 3.9 +/- 0.8 ml x 100 g(-1) x min(-1), P...

  1. Raster-Mode Continuous-Flow Liquid Microjunction Mass Spectrometry Imaging of Proteins in Thin Tissue Sections.

    Science.gov (United States)

    Griffiths, Rian L; Randall, Elizabeth C; Race, Alan M; Bunch, Josephine; Cooper, Helen J

    2017-06-06

    Mass spectrometry imaging by use of continuous-flow liquid microjunction sampling at discrete locations (array mode) has previously been demonstrated. In this Letter, we demonstrate continuous-flow liquid microjunction mass spectrometry imaging of proteins from thin tissue sections in raster mode and discuss advantages (a 10-fold reduction in analysis time) and challenges (suitable solvent systems, data interpretation) of the approach. Visualization of data is nontrivial, requiring correlation of solvent-flow, mass spectral data acquisition rate, data quality, and liquid microjunction sampling area. The latter is particularly important for determining optimum pixel size. The minimum achievable pixel size is related to the scan time of the instrument used. Here we show a minimum achievable pixel size of 50 μm (x-dimension) when using an Orbitrap Elite; however a pixel size of 600 μm is recommended in order to minimize the effects of oversampling on image accuracy.

  2. Three dimensional three component whole heart cardiovascular magnetic resonance velocity mapping: comparison of flow measurements from 3D and 2D acquisitions.

    Science.gov (United States)

    Brix, Lau; Ringgaard, Steffen; Rasmusson, Allan; Sørensen, Thomas Sangild; Kim, W Yong

    2009-02-20

    Two-dimensional, unidirectionally encoded, cardiovascular magnetic resonance (CMR) velocity mapping is an established technique for the quantification of blood flow in large vessels. However, it requires an operator to correctly align the planes of acquisition. If all three directional components of velocity are measured for each voxel of a 3D volume through the phases of the cardiac cycle, blood flow through any chosen plane can potentially be calculated retrospectively. The initial acquisition is then more time consuming but relatively operator independent. To compare the curves and volumes of flow derived from conventional 2D and comprehensive 3D flow acquisitions in a steady state flow model, and in vivo through planes transecting the ascending aorta and pulmonary trunk in 10 healthy volunteers. Using a 1.5 T Phillips Intera CMR system, 3D acquisitions used an anisotropic 3D segmented k-space phase contrast gradient echo sequence with a short EPI readout, with prospective ECG and diaphragm navigator gating. The 2D acquisitions used segmented k-space phase contrast with prospective ECG and diaphragm navigator gating. Quantitative flow analyses were performed retrospectively with dedicated software for both the in vivo and in vitro acquisitions. Analysis of in vitro data found the 3D technique to have overestimated the continuous flow rate by approximately 5% across the entire applied flow range. In vivo, the 2D and the 3D techniques yielded similar volumetric flow curves and measurements. Aortic flow: (mean +/- SD), 2D = 89.5 +/- 13.5 ml & 3D = 92.7 +/- 17.5 ml. Pulmonary flow: 2D = 98.8 +/- 18.4 ml & 3D = 94.9 +/- 19.0 ml). Each in vivo 3D acquisition took about 8 minutes or more. Flow measurements derived from the 3D and 2D acquisitions were comparable. Although time consuming, comprehensive 3D velocity acquisition could be relatively operator independent, and could potentially yield information on flow through several retrospectively chosen planes, for

  3. On conditions of negativity of friction resistance for nonstationary modes of blood flow and possible mechanism of affecting of environmental factors on energy effectiveness of cardiovascular system function

    Directory of Open Access Journals (Sweden)

    Sergey G. Chefranov

    2013-05-01

    Full Text Available It is shown that initiated by action of molecular viscosity impulse flow, directed usually from the moving fluid to limiting it solid surface, can, under certain conditions, turn to zero and get negative values in the case of non-stationary flow caused by alternating in time longitudinal (along the pipe axis pressure gradient. It is noted that this non-equilibrium mechanism of negative friction resistance in the similar case of pulsating blood flow in the blood vessels, in addition to the stable to turbulent disturbances swirled blood flow structure providing, can also constitute hydro-mechanical basis of the observed but not explained yet paradoxically high energy effectiveness of the normal functioning of the cardiovascular system (CVS. We consider respective mechanism of affecting on the stability of the normal work of CVS by environmental variable factors using shifting of hydro-dynamic mode with negative resistance realization range boundaries and variation of linear hydrodynamic instability leading to the structurally stable swirled blood flow organization.

  4. Effect of hindlimb unweighting on tissue blood flow in the rat

    Science.gov (United States)

    Mcdonald, K. S.; Delp, M. D.; Fitts, R. H.

    1992-01-01

    This study characterized distribution of blood flow in the rat during hindlimb unweighting (HU), and post-HU standing and exercise. The relationship between reduced hindlimb blood flow and the previously observed elevation in anaerobic metabolism observed with contractile activity in the atrophied soleus muscle was examined (Witzmann et al., 1992). Blood flow was measured during unweighting, normal standing, and running on a treadmill (15 m/min), after 15 days of HU or cage control. For another group blood flow was measured during preexercise treadmill standing and treadmill running. During unweighting, PE standing, and running no difference in soleus blood flow was observed between groups. Muscles composed mainly of fast twitch glycolytic fibers received greater blood flow during chronic unweighting. With exercise blood flow to visceral organs was reduced in control animals, a similar change was not seen in 15 day HU rats. These changes suggest a reduction in the ability of the sympathetic nervous system to distribute cardiac output after chronic HU. A reduction in blood flow to the soleus during exercise was not observed after HU and so does not explain the increased dependence of the atrophied soleus on anerobic energy production during contractile activity.

  5. Tricuspid flow and regurgitation in congenital heart disease and pulmonary hypertension: comparison of 4D flow cardiovascular magnetic resonance and echocardiography.

    Science.gov (United States)

    Driessen, Mieke M P; Schings, Marjolijn A; Sieswerda, Gertjan Tj; Doevendans, Pieter A; Hulzebos, Erik H; Post, Marco C; Snijder, Repke J; Westenberg, Jos J M; van Dijk, Arie P J; Meijboom, Folkert J; Leiner, Tim

    2018-01-15

    Tricuspid valve (TV) regurgitation (TR) is a common complication of pulmonary hypertension and right-sided congenital heart disease, associated with increased morbidity and mortality. Estimation of TR severity by echocardiography and conventional cardiovasvular magnetic resonance (CMR) is not well validated and has high variability. 4D velocity-encoded (4D-flow) CMR was used to measure tricuspid flow in patients with complex right ventricular (RV) geometry and varying degrees of TR. The aims of the present study were: 1) to assess accuracy of 4D-flow CMR across the TV by comparing 4D-flow CMR derived TV effective flow to 2D-flow derived effective flow across the pulmonary valve (PV); 2) to assess TV 4D-flow CMR reproducibility, and 3) to compare TR grade by 4D-flow CMR to TR grade by echocardiography. TR was assessed by both 4D-flow CMR and echocardiography in 21 healthy subjects (41.2 ± 10.5 yrs., female 7 (33%)) and 67 RV pressure-load patients (42.7 ± 17.0 yrs., female 32 (48%)). The CMR protocol included 4D-flow CMR measurement across the TV, 2D-flow measurement across the PV and conventional planimetric measurements. TR grading on echocardiographic images was performed based on the international recommendations. Bland-Altman analysis and intra-class correlation coefficients (ICC) were used to asses correlations and agreement. TV effective flow measured by 4D-flow CMR showed good correlation and agreement with PV effective flow measured by 2D-flow CMR with ICC = 0.899 (p limits of agreement -20.39 to 16.81] (p = 0.084). Intra-observer agreement for effective flow (ICC = 0.981; mean difference - 1.51 ml [-12.88 to 9.86]) and regurgitant fraction (ICC = 0.910; mean difference 1.08% [-7.90; 10.06]) was good. Inter-observer agreement for effective flow (ICC = 0.935; mean difference 2.12 ml [-15.24 to 19.48]) and regurgitant fraction (ICC = 0.968; mean difference 1.10% [-7.96 to 5.76]) were comparable. In 25/65 (38.5%) TR

  6. Concomitant administration of nitrous oxide and remifentanil reduces oral tissue blood flow without decreasing blood pressure during sevoflurane anesthesia in rabbits.

    Science.gov (United States)

    Kasahara, Masataka; Ichinohe, Tatsuya; Okamoto, Sota; Okada, Reina; Kanbe, Hiroaki; Matsuura, Nobuyuki

    2015-06-01

    To determine whether continuous administration of nitrous oxide and remifentanil—either alone or together—alters blood flow in oral tissues during sevoflurane anesthesia. Eight male tracheotomized Japanese white rabbits were anesthetized with sevoflurane under mechanical ventilation. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), common carotid arterial blood flow (CCBF), tongue mucosal blood flow (TMBF), mandibular bone marrow blood flow (BBF), masseter muscle blood flow (MBF), upper alveolar tissue blood flow (UBF), and lower alveolar tissue blood flow (LBF) were recorded in the absence of all test agents and after administration of the test agents (50 % nitrous oxide, 0.4 μg/kg/min remifentanil, and their combination) for 20 min. Nitrous oxide increased SBP, DBP, MAP, CCBF, BBF, MBF, UBF, and LBF relative to baseline values but did not affect HR or TMBF. Remifentanil decreased all hemodynamic variables except DBP. Combined administration of nitrous oxide and remifentanil recovered SBP, DBP, MAP, and CCBF to baseline levels, but HR and oral tissue blood flow remained lower than control values. Our findings suggest that concomitant administration of nitrous oxide and remifentanil reduces blood flow in oral tissues without decreasing blood pressure during sevoflurane anesthesia in rabbits.

  7. Soft tissue models: easy and inexpensive flexible 3D printing as a help in surgical planning of cardiovascular disorders

    Science.gov (United States)

    Starosolski, Zbigniew; Ezon, David S.; Krishnamurthy, Rajesh; Dodd, Nicholas; Heinle, Jeffrey; Mckenzie, Dean E.; Annapragada, Ananth

    2017-03-01

    We developed a technology that allows a simple desktop 3D printer with dual extruder to fabricate 3D flexible models of Major AortoPulmonary Collateral Arteries. The study was designed to assess whether the flexible 3D printed models could help during surgical planning phase. Simple FDM 3D printers are inexpensive, versatile in use and easy to maintain, but complications arise when the designed model is complex and has tubular structures with small diameter less than 2mm. The advantages of FDM printers are cost and simplicity of use. We use precisely selected materials to overcome the obstacles listed above. Dual extruder allows to use two different materials while printing, which is especially important in the case of fragile structures like pulmonary vessels and its supporting structures. The latter should not be removed by hand to avoid a truncation of the model. We utilize the water soluble PVA as a supporting structure and Poro-Lay filament for flexible model of AortoPulmonary collateral arteries. Poro-Lay filament is different as compared to all the other flexible ones like polymer-based. Poro-Lay is rigid while printing and this allows printing of structures small in diameter. It achieves flexibility after washing out of printed model with water. It becomes soft in touch and gelatinous. Using both PVA and Poro-Lay gives a huge advantage allowing to wash out the supporting structures and achieve flexibility in one washing operation, saving time and avoiding human error with cleaning the model. We evaluated 6 models for MAPCAS surgical planning study. This approach is also cost-effective - an average cost of materials for print is less than $15; models are printed in facility without any delays. Flexibility of 3D printed models approximate soft tissues properly, mimicking Aortopulmonary collateral arteries. Second utilization models has educational value for both residents and patients' family. Simplification of 3D flexible process could help in other models

  8. Combined Assessment of Stress Myocardial Perfusion Cardiovascular Magnetic Resonance and Flow Measurement in the Coronary Sinus Improves Prediction of Functionally Significant Coronary Stenosis Determined by Fractional Flow Reserve in Multivessel Disease.

    Science.gov (United States)

    Nakamori, Shiro; Sakuma, Hajime; Dohi, Kaoru; Ishida, Masaki; Tanigawa, Takashi; Yamada, Akimasa; Takase, Shinichi; Nakajima, Hiroshi; Sawai, Toshiki; Masuda, Jun; Nagata, Motonori; Ichikawa, Yasutaka; Kitagawa, Kakuya; Fujii, Eitaro; Yamada, Norikazu; Ito, Masaaki

    2018-01-26

    Recent studies using stress-rest perfusion cardiovascular magnetic resonance (CMR) demonstrated a close correlation between myocardial ischemia and reduced fractional flow reserve (FFR). However, its diagnostic concordance may be reduced in patients with multivessel disease. We sought to evaluate the concordance of adenosine stress-rest perfusion CMR for predicting reduced FFR, and to determine the additive value of measuring global coronary flow reserve (CFR) in the coronary sinus in multivessel disease. Ninety-six patients with angiographic luminal narrowing >50% underwent comprehensive CMR study and FFR measurements in 139 coronary vessels. FFR flow measured by phase-contrast cine CMR. In 25 patients with single-vessel disease, visual assessment of perfusion CMR yielded high diagnostic concordance for predicting flow-limiting stenosis, with the area under receiver operating characteristic curve of 0.93 on a per-patient basis. However, in 71 patients with multivessel disease, perfusion CMR underestimated flow-limiting stenosis, resulting in the reduced area under receiver operating characteristic curve of 0.74. When CFR of flow measurement in the coronary sinus is useful for detecting reduced FFR in multivessel disease. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  9. Blood flow and tissue oxygen pressures of liver and pancreas in rats: effects of volatile anesthetics and of hemorrhage.

    Science.gov (United States)

    Vollmar, B; Conzen, P F; Kerner, T; Habazettl, H; Vierl, M; Waldner, H; Peter, K

    1992-09-01

    The object of this investigation was to compare the effects of volatile anesthetics and of hemorrhage at comparable arterial blood pressures on splanchnic blood flow (radioactive microspheres) and tissue oxygenation of the liver and pancreas (surface PO2 [PSO2] electrodes). In contrast to earlier studies, we did not use identical minimum alveolar anesthetic concentration multiples as a reference to compare volatile anesthetics; rather, we used the splanchnic perfusion pressure. Under general anesthesia (intravenous chloralose) and controlled ventilation, 12 Sprague-Dawley rats underwent laparotomy to allow access to abdominal organs. Mean arterial pressure was decreased from 84 +/- 3 mm Hg (mean +/- SEM) at control to 50 mm Hg by 1.0 +/- 0.1 vol% halothane, 2.2 +/- 0.2 vol% enflurane, and 2.3 +/- 0.1 vol% isoflurane in a randomized sequence. For hemorrhagic hypotension, blood was withdrawn gradually until a mean arterial pressure of 50 mm Hg was attained. Volatile anesthetics and hemorrhage reduced cardiac output, and hepatic arterial, portal venous, and total hepatic blood flows by comparable degrees. Mean hepatic PSO2 decreased significantly from 30.7 +/- 2.6 mm Hg at control to 17.4 +/- 2 and 17.5 +/- 2 mm Hg during enflurane and isoflurane (each P less than 0.05) anesthesia, respectively. The decrease to 11.5 +/- 2.5 mm Hg was more pronounced during halothane anesthesia. Hemorrhagic hypotension was associated with the lowest hepatic PSO2 (3.4 +/- 1.3 mm Hg) and the highest number of hypoxic (0-5 mm Hg 86%) and anoxic PSO2 values (0 mm Hg 46%). Pancreatic blood flow and oxygenation remained unchanged from control during halothane and enflurane administration, whereas isoflurane increased both variables. Hemorrhagic hypotension slightly reduced pancreatic flow (-8%) but significantly decreased PSO2 from 58 +/- 5 mm Hg at control to 36 +/- 3 mm Hg, with 7% of all measured values in the hypoxic range. Thus, volatile anesthetics preserved pancreatic but not hepatic

  10. Impaired autoregulation of blood flow in skeletal muscle and subcutaneous tissue in long-term Type 1 (insulin-dependent) diabetic patients with microangiopathy

    DEFF Research Database (Denmark)

    Faris, I; Vagn Nielsen, H; Henriksen, O

    1983-01-01

    Autoregulation of blood flow was studied in skeletal muscle and subcutaneous tissue in seven Type 1 (insulin-dependent) diabetic patients (median age: 36 years) with nephropathy and retinopathy and in eight normal subjects of the same age. Blood flow was measured by the local 133Xe washout...... technique. Reduction in arterial perfusion pressure was produced by elevating the limb 20 and 40 cm above heart level. Blood flow remained within 10% of control values when the limb was elevated in normal subjects. In five of the seven diabetic subjects blood flow fell significantly in both tissues when...

  11. Human adipose tissue blood flow during prolonged exercise, III. Effect of beta-adrenergic blockade, nicotinic acid and glucose infusion

    DEFF Research Database (Denmark)

    Bülow, J

    1981-01-01

    of work. No increase in lipolysis and no increase in ATBF were found when lipolysis was blocked by nicotinic acid (0.3 g/h). Propranolol treatment (0.15 mg/kg) reduced lipolysis and nearly abolished the increase in ATBF during exercise. Intravenous administration of glucose (about 0.25 g/min) did......Subcutaneous adipose tissue blood flow (ATBF) was measured in six male subjects by the 133Xe-washout technique during 3-4 h of exercise at a work load corresponding to an oxygen uptake of about 1.71/min. The measurements were done during control conditions, during blockade of lipolysis by nicotinic...

  12. Tissue vascularization through 3D printing: Will technology bring us flow?

    Science.gov (United States)

    Paulsen, S J; Miller, J S

    2015-05-01

    Though in vivo models provide the most physiologically relevant environment for studying tissue function, in vitro studies provide researchers with explicit control over experimental conditions and the potential to develop high throughput testing methods. In recent years, advancements in developmental biology research and imaging techniques have significantly improved our understanding of the processes involved in vascular development. However, the task of recreating the complex, multi-scale vasculature seen in in vivo systems remains elusive. 3D bioprinting offers a potential method to generate controlled vascular networks with hierarchical structure approaching that of in vivo networks. Bioprinting is an interdisciplinary field that relies on advances in 3D printing technology along with advances in imaging and computational modeling, which allow researchers to monitor cellular function and to better understand cellular environment within the printed tissue. As bioprinting technologies improve with regards to resolution, printing speed, available materials, and automation, 3D printing could be used to generate highly controlled vascularized tissues in a high throughput manner for use in regenerative medicine and the development of in vitro tissue models for research in developmental biology and vascular diseases. © 2015 Wiley Periodicals, Inc.

  13. The Regulation of Blood Flow and Metabolism in Adipose Tissue: Evidence for a Role of Adenosine

    Science.gov (United States)

    1984-10-17

    as increased glycogenolysis and increased lipolysis. Beta2-receptors mediate vasodilation. Alpha- receptor activation cauaes vasoconstriction...administration of norepine- phrine, the intraarterial infusion has limited systemic actions and limited, if any, liver glycogenolysis occurs. The...control tissues approached those reported for cardiac muscle of dogs and were much greater than those reported for gracilis muscle of cats (Bockman

  14. Blood flow in skin, subcutaneous adipose tissue and skeletal muscle in the forearm of normal man during an oral glucose load

    DEFF Research Database (Denmark)

    Bülow, J; Astrup, A; Christensen, N J

    1987-01-01

    Blood flow to the forearm, and the subcutaneous tissue and skin in the forearm were measured by strain gauge plethysmography, 133Xe-elimination and Laser Doppler flowmetry during an oral glucose load (I g glucose kg-1 lean body mass) and during control conditions. The forearm blood flow remained......, muscle blood flow decreased about 20-30% during both experiments. Proximal nervous blockade did not abolish the glucose-induced vasodilatation in subcutaneous tissue. In the glucose experiment, arterial glucose concentration increased to 7.8 +/- 1.17 mmol l-1 30 min after the load was given...... constant during both experiments. Glucose induced a two-fold vasodilatation in subcutaneous tissue. In skin, glucose induced a relative vasodilatation and later a relative vasoconstriction compared with control experiments. When estimated from forearm blood flow and subcutaneous and skin blood flows...

  15. Reinforced chitosan-based heart valve scaffold and utility of bone marrow-derived mesenchymal stem cells for cardiovascular tissue engineering

    Science.gov (United States)

    Albanna, Mohammad Zaki

    utility for cardiovascular tissue engineering applications. Moreover, we evaluated the effect of various glycosaminoglycans (GAGs) on MSCs morphology and proliferation. Lastly, we studied the effect of stiffness of mechanically improved chitosan fibers on MSCs viability, attachment and proliferation. Results showed that MSCs proliferation improved in proportion to fiber stiffness.

  16. Effects of acetazolamide on cerebral blood flow and brain tissue oxygenation

    DEFF Research Database (Denmark)

    Lassen, N A; Friberg, L; Kastrup, J

    1987-01-01

    Oral administration of 1 g of acetazolamide to 8 normal subjects studied at sea level and in normoxia caused an acute increase in cerebral blood flow (CBF). During the subsequent prolonged oral treatment with 1 g of acetazolamide daily, CBF returned to normal within 2 days. The alveolar CO2 tension...

  17. Reversal of high pancreatic islet and white adipose tissue blood flow in type 2 diabetic GK rats by administration of the beta3-adrenoceptor inhibitor SR-59230A.

    Science.gov (United States)

    Pettersson, U S; Henriksnäs, J; Jansson, L

    2009-08-01

    Previous studies have shown that the Goto-Kakizaki (GK) rat, a nonobese type 2 diabetes model, has an increased white adipose tissue (WAT) and islet blood flow when compared with control rats. The aim of the study was to examine if these increased blood flow values in GK rats could be affected by the beta(3)-adrenoceptor antagonist SR-59230A. We measured organ blood flow with a microsphere technique 10 min after administration of SR-59230A (1 mg/kg body wt), or the corresponding volume of 0.9% NaCl solution (1 ml/kg body wt) in rats anaesthetized with thiobutabarbital. The GK rat had an increased blood flow in all intra-abdominal adipose tissue depots except for the sternal fat pad compared with Wistar-Furth (WF) rats. However, no differences were seen in the blood perfusion of subcutaneous white or brown adipose tissue. The blood flow was also increased in both the pancreas and in the islets in the GK rat compared with WF rats. SR-59230A treatment affected neither WAT nor pancreatic blood flow in WF rats. In GK rats, on the other hand, SR-59230A decreased both WAT and islet blood flow values to values similar to those seen in control WF rats. The whole pancreatic blood flow was not affected by SR-59230A administration in GK rats. Interestingly, the brown adipose tissue blood flow in GK rats increased after SR-59230A administration. These results suggest that beta(3)-adrenoceptors are involved in regulation of blood flow both in islet and in adipose tissue.

  18. Systemic-to-pulmonary collateral flow in patients with palliated univentricular heart physiology: measurement using cardiovascular magnetic resonance 4D velocity acquisition

    Directory of Open Access Journals (Sweden)

    Valverde Israel

    2012-04-01

    Full Text Available Abstract Background Systemic-to-pulmonary collateral flow (SPCF may constitute a risk factor for increased morbidity and mortality in patients with single-ventricle physiology (SV. However, clinical research is limited by the complexity of multi-vessel two-dimensional (2D cardiovascular magnetic resonance (CMR flow measurements. We sought to validate four-dimensional (4D velocity acquisition sequence for concise quantification of SPCF and flow distribution in patients with SV. Methods 29 patients with SV physiology prospectively underwent CMR (1.5 T (n = 14 bidirectional cavopulmonary connection [BCPC], age 2.9 ± 1.3 years; and n = 15 Fontan, 14.4 ± 5.9 years and 20 healthy volunteers (age, 28.7 ± 13.1 years served as controls. A single whole-heart 4D velocity acquisition and five 2D flow acquisitions were performed in the aorta, superior/inferior caval veins, right/left pulmonary arteries to serve as gold-standard. The five 2D velocity acquisition measurements were compared with 4D velocity acquisition for validation of individual vessel flow quantification and time efficiency. The SPCF was calculated by evaluating the disparity between systemic (aortic minus caval vein flows and pulmonary flows (arterial and venour return. The pulmonary right to left and the systemic lower to upper body flow distribution were also calculated. Results The comparison between 4D velocity and 2D flow acquisitions showed good Bland-Altman agreement for all individual vessels (mean bias, 0.05±0.24 l/min/m2, calculated SPCF (−0.02±0.18 l/min/m2 and significantly shorter 4D velocity acquisition-time (12:34 min/17:28 min,p 2; Fontan 0.62±0.82 l/min/m2 and not in controls (0.01 + 0.16 l/min/m2, (3 inverse relation of right/left pulmonary artery perfusion and right/left SPCF (Pearson = −0.47,p = 0.01 and (4 upper to lower body flow distribution trend related to the weight (r = 0.742, p  Conclusions 4D

  19. Regional disturbances in blood flow and metabolism in equine limb wound healing with formation of exuberant granulation tissue.

    Science.gov (United States)

    Sørensen, Mette A; Petersen, Lars J; Bundgaard, Louise; Toft, Nils; Jacobsen, Stine

    2014-01-01

    As in other fibroproliferative disorders, hypoxia has been suggested to play a key role in the pathogenesis of exuberant granulation tissue (EGT). The purpose of this study was to investigate metabolism and blood flow locally in full-thickness wounds healing with (limb wounds) and without (body wounds) formation of EGT. Microdialysis was used to recover endogenous metabolites from the wounds, and laser Doppler flowmetry was used to measure blood flow. Measurements were performed before wounding and 1-28 days after wounding. Blood flow was consistently lower in limb wounds than in body wounds throughout the study period with no change over time. After wounding and throughout the study period, the glucose concentration was significantly lower in limb wounds than in body wounds, whereas the lactate level showed a significantly higher concentration in limb wounds. The lactate/glucose ratio displayed a significant difference between body and limb wounds. In conclusion, the metabolic disturbances may suggest an inadequate oxygen supply during the wound healing process in equine limb wounds healing with EGT. This may be related to the inherently decreased perfusion in the wound bed of limb wounds. © 2014 by the Wound Healing Society.

  20. An in vivo approach for globally estimating the drug flow between blood and tissue for nafamostat mesilate: the main hydrolysis site determination in human.

    Science.gov (United States)

    Cao, Yan-Guang; Chen, Yuan-Cheng; Hao, Kun; Zhang, Ming; Liu, Xiao-Quan

    2008-11-01

    Nafamostat mesilate, an ester drug with extensive hydrolysis in vivo, exhibits species difference in the relative contribution for its hydrolysis in blood and tissues. For the rat, the main hydrolysis site may be blood and human may be tissue (mainly by liver). The paper gave in vivo evidence that human tissue may give more contribution for its hydrolysis. In the initial phase of drug administration, the drug accumulating level in tissue was low; the efflux fraction from tissue into blood can be ignorable comparing with the drug influx into tissue. Based on urine and plasma metabolite analysis, we concluded that in the initial phase almost all the drug hydrolysis in blood was excreted into urine. Then according to the initial urine metabolite analysis, we can estimate the drug hydrolysis rate in blood. The rate of drug diffusion from blood into tissues can be deduced based on the mass balance analysis of the initial blood drug. With the estimated rate constants, the drug efflux from tissues into blood was calculated according to equation: OFT-B (efflux from tissues) = OFB-U (blood hydrolysis fraction)+OFB-T (influx into tissues)-DB (hydrolysis in blood). The net flow (influent flux minus effluent flux) represented the drug hydrolysis fraction in tissue. As the result indicated, in human about 20% drug administrated was hydrolyzed in blood and nearly 80% in tissues. The relative hydrolysis fraction indicated that the main hydrolysis site in human body may locate in tissue, which was different to rats.

  1. In Situ Cardiovascular Tissue Engineering

    NARCIS (Netherlands)

    Talacua, H

    2016-01-01

    In this thesis, the feasibility of in situ TE for vascular and valvular purposes were tested with the use of different materials, and animal models. First, the feasibility of a decellularized biological scaffold (pSIS-ECM) as pulmonary heart valve prosthesis is examined in sheep (Chapter 2). Next,

  2. Improvements in tissue blood flow and lumbopelvic stability after lumbopelvic core stabilization training in patients with chronic non-specific low back pain.

    Science.gov (United States)

    Paungmali, Aatit; Henry, Leonard Joseph; Sitilertpisan, Patraporn; Pirunsan, Ubon; Uthaikhup, Sureeporn

    2016-01-01

    [Purpose] This study investigated the effects of lumbopelvic stabilization training on tissue blood flow changes in the lumbopelvic region and lumbopelvic stability compared to placebo treatment and controlled intervention among patients with chronic non-specific low back pain. [Subjects and Methods] A total of 25 participants (7 males, 18 females; mean age, 33.3 ± 14.4 years) participated in this within-subject, repeated-measures, double-blind, placebo-controlled comparison trial. The participants randomly underwent three types of interventions that included lumbopelvic stabilization training, placebo treatment, and controlled intervention with 48 hours between sessions. Lumbopelvic stability and tissue blood flow were measured using a pressure biofeedback device and a laser Doppler flow meter before and after the interventions. [Results] The repeated-measures analysis of variance results demonstrated a significant increase in tissue blood flow over the lumbopelvic region tissues for post- versus pre-lumbopelvic stabilization training and compared to placebo and control interventions. A significant increase in lumbopelvic stability before and after lumbopelvic stabilization training was noted, as well as upon comparison to placebo and control interventions. [Conclusion] The current study supports an increase in tissue blood flow in the lumbopelvic region and improved lumbopelvic stability after core training among patients with chronic non-specific low back pain.

  3. Extracellular vesicles in cardiovascular homeostasis and disease.

    Science.gov (United States)

    Hutcheson, Joshua D; Aikawa, Elena

    2018-05-01

    Extracellular vesicles have emerged as one of the most important means through which cells interact with each other and the extracellular environment, but extracellular vesicle research remains challenging due to their small size, limited amount of material required for traditional molecular biology assays and inconsistency in the methods of their isolation. The advent of new technologies and standards in the field, however, have led to increased mechanistic insight into extracellular vesicle function. Herein, the latest studies on the role of extracellular vesicles in cardiovascular physiology and disease are discussed. Extracellular vesicles help control cardiovascular homeostasis and remodelling by mediating communication between cells and directing alterations in the extracellular matrix to respond to changes in the environment. The message carried from the parent cell to extracellular space can be intended for both local (within the same tissue) and distal (downstream of blood flow) targets. Pathological cargo loaded within extracellular vesicles could further result in various diseases. On the contrary, new studies indicate that injection of extracellular vesicles obtained from cultured cells into diseased tissues can promote restoration of normal tissue function. Extracellular vesicles are an integral part of cell and tissue function, and harnessing the properties inherent to extracellular vesicles may provide a therapeutic strategy to promote tissue regeneration.

  4. Repetitive reduction of uterine blood flow and its influence on fetal transcutaneous PO2 and cardiovascular variables.

    Science.gov (United States)

    Jensen, A; Künzel, W; Kastendieck, E

    1985-04-01

    The influence of repeated asphyxia on fetal transcutaneous PO2, relative local skin perfusion, heart rate, blood gases and pH was investigated in 15 experiments on 8 acutely instrumented sheep fetuses in utero between 125 and 145 days gestation (term is 147 days). Uterine blood flow was intermittently arrested (11 times within 33 min) by intra-vascular maternal aortic occlusion, exposing the fetuses to repeated episodes of asphyxia of 30 (n = 3), 60 (n = 9) and 90 (n = 3) s duration. The fetal transcutaneous PO2 fell as the duration of asphyxia (2 alpha less than 0.01), heart rate deceleration area (2 alpha less than 0.01) and acidaemia (2 alpha less than 0.01) increased. With decreasing skin perfusion, which was dependent on the duration of asphyxia (2 alpha less than 0.001) and acidaemia (2 alpha less than 0.001), a discrepancy developed between transcutaneous and arterial PO2. The increase (delta) in transcutaneous-arterial PO2 difference was related linearly to the duration of asphyxia (2 alpha less than 0.01), the mean haemoglobin oxygen saturation (2 alpha less than 0.001), acidaemia (2 alpha less than 0.001) and relative local skin flow (2 alpha less than 0.05). It was highest after severe episodes of asphyxia (90 s), when O2 saturation, skin blood flow and arterial blood pH values were low. Fetal heart rate deceleration area was only correlated with the cutaneous-arterial PO2 difference when the mean fetal haemoglobin oxygen saturation was below 35%. Thus, a discrimination of heart rate decelerations that are significant for the fetus seems to be possible, when associated with low transcutaneous PO2 values. We conclude that in the sheep fetus transcutaneous PO2 measurements during repeated asphyxial episodes yield information on fetal oxygenation and on the skin vasomotor response.

  5. Cardiovascular magnetic resonance in hypertrophic cardiomyopathy and infiltrative cardiomyopathy

    OpenAIRE

    Schofield, R.; Manacho, K.; Castelletti, S.; Moon, J. C.

    2016-01-01

    Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease. Cardiac imaging plays a key role in the diagnosis and management, with cardiovascular magnetic resonance (CMR) an important modality. CMR provides a number of different techniques in one examination: structure and function, flow imaging and tissue characterisation particularly with the late gadolinium enhancement (LGE) technique. Other techniques include vasodilator perfusion, mapping (especially T1 mapping and ex...

  6. Temporal change of myocardial tissue character is associated with left ventricular reverse remodeling in patients with dilated cardiomyopathy: A cardiovascular magnetic resonance study.

    Science.gov (United States)

    Nabeta, Takeru; Inomata, Takayuki; Fujita, Teppei; Iida, Yuichiro; Ikeda, Yuki; Sato, Takanori; Ishii, Shunsuke; Maekawa, Emi; Mizutani, Tomohiro; Naruke, Takashi; Koitabashi, Toshimi; Inoue, Yusuke; Ako, Junya

    2017-08-01

    Prognostic significance of temporal change in myocardial tissue characterization by cardiovascular magnetic resonance (CMR) has not been elucidated in patients with non-ischemic dilated cardiomyopathy (DCM). Sixty-eight patients with newly-diagnosed DCM who underwent CMR including late gadolinium enhancement (LGE) both at baseline and during follow-up period were enrolled. LGE score was defined by a signal intensity of ≥5 standard deviations above the remote reference myocardium mean. Left ventricular reverse remodeling (LVRR) defined as a LV ejection fraction increase of ≥10% and a decrease in indexed LV end-diastolic diameter of ≥10% compared to those at baseline was detected in 38% of the patients. There was no significant difference in LGE score between baseline and follow-up (5.8% vs. 7.3%; p=0.38). The change in LGE area (delta-LGE) was significantly lower in patients with LVRR than those without (-0.5%±3.4% vs. 3.0±7.4%; p=0.02). On the other hand, T2 ratio during the follow-up significantly reduced (1.95±0.48 vs. 1.67±0.56; p<0.01); however, there was no significant difference in the change in T2 ratio between patients with LVRR and those without (-0.29±0.73 vs. -0.27±0.66; p=0.88). Multivariate logistic analysis indicated that baseline LGE score [odds ratio; 0.78; 95% confidence interval (CI) 0.66 to 0.90; p<0.01] together with delta-LGE (odds ratio; 0.77; 95% CI 0.61 to 0.92; p=0.01) were independently associated with subsequent LVRR (p<0.01). The temporal change of LGE-CMR score during the clinical course was significantly correlated with following LVRR. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  7. Rapid automatic segmentation of abnormal tissue in late gadolinium enhancement cardiovascular magnetic resonance images for improved management of long-standing persistent atrial fibrillation.

    Science.gov (United States)

    Giannakidis, Archontis; Nyktari, Eva; Keegan, Jennifer; Pierce, Iain; Suman Horduna, Irina; Haldar, Shouvik; Pennell, Dudley J; Mohiaddin, Raad; Wong, Tom; Firmin, David N

    2015-10-07

    Atrial fibrillation (AF) is the most common heart rhythm disorder. In order for late Gd enhancement cardiovascular magnetic resonance (LGE CMR) to ameliorate the AF management, the ready availability of the accurate enhancement segmentation is required. However, the computer-aided segmentation of enhancement in LGE CMR of AF is still an open question. Additionally, the number of centres that have reported successful application of LGE CMR to guide clinical AF strategies remains low, while the debate on LGE CMR's diagnostic ability for AF still holds. The aim of this study is to propose a method that reliably distinguishes enhanced (abnormal) from non-enhanced (healthy) tissue within the left atrial wall of (pre-ablation and 3 months post-ablation) LGE CMR data-sets from long-standing persistent AF patients studied at our centre. Enhancement segmentation was achieved by employing thresholds benchmarked against the statistics of the whole left atrial blood-pool (LABP). The test-set cross-validation mechanism was applied to determine the input feature representation and algorithm that best predict enhancement threshold levels. Global normalized intensity threshold levels T PRE  = 1 1/4 and T POST  = 1 5/8 were found to segment enhancement in data-sets acquired pre-ablation and at 3 months post-ablation, respectively. The segmentation results were corroborated by using visual inspection of LGE CMR brightness levels and one endocardial bipolar voltage map. The measured extent of pre-ablation fibrosis fell within the normal range for the specific arrhythmia phenotype. 3D volume renderings of segmented post-ablation enhancement emulated the expected ablation lesion patterns. By comparing our technique with other related approaches that proposed different threshold levels (although they also relied on reference regions from within the LABP) for segmenting enhancement in LGE CMR data-sets of AF patients, we illustrated that the cut-off levels employed by other centres

  8. Vortex flow during early and late left ventricular filling in normal subjects: quantitative characterization using retrospectively-gated 4D flow cardiovascular magnetic resonance and three-dimensional vortex core analysis.

    Science.gov (United States)

    Elbaz, Mohammed S M; Calkoen, Emmeline E; Westenberg, Jos J M; Lelieveldt, Boudewijn P F; Roest, Arno A W; van der Geest, Rob J

    2014-09-27

    LV diastolic vortex formation has been suggested to critically contribute to efficient blood pumping function, while altered vortex formation has been associated with LV pathologies. Therefore, quantitative characterization of vortex flow might provide a novel objective tool for evaluating LV function. The objectives of this study were 1) assess feasibility of vortex flow analysis during both early and late diastolic filling in vivo in normal subjects using 4D Flow cardiovascular magnetic resonance (CMR) with retrospective cardiac gating and 3D vortex core analysis 2) establish normal quantitative parameters characterizing 3D LV vortex flow during both early and late ventricular filling in normal subjects. With full ethical approval, twenty-four healthy volunteers (mean age: 20±10 years) underwent whole-heart 4D Flow CMR. The Lambda2-method was used to extract 3D LV vortex ring cores from the blood flow velocity field during early (E) and late (A) diastolic filling. The 3D location of the center of vortex ring core was characterized using cylindrical cardiac coordinates (Circumferential, Longitudinal (L), Radial (R)). Comparison between E and A filling was done with a paired T-test. The orientation of the vortex ring core was measured and the ring shape was quantified by the circularity index (CI). Finally, the Spearman's correlation between the shapes of mitral inflow pattern and formed vortex ring cores was tested. Distinct E- and A-vortex ring cores were observed with centers of A-vortex rings significantly closer to the mitral valve annulus (E-vortex L=0.19±0.04 versus A-vortex L=0.15±0.05; p=0.0001), closer to the ventricle's long-axis (E-vortex: R=0.27±0.07, A-vortex: R=0.20±0.09, p=0.048) and more elliptical in shape (E-vortex: CI=0.79±0.09, A-vortex: CI=0.57±0.06; vortex. The circumferential location and orientation relative to LV long-axis for both E- and A-vortex ring cores were similar. Good to strong correlation was found between vortex shape and

  9. On the correlation between the radioprotective effectiveness of serotonin and its derivatives and their ability to modify the local blood flow in animal tissues

    International Nuclear Information System (INIS)

    Abramov, M.M.; Vasin, M.V.

    1978-01-01

    Radioprotective effectiveness of serotonin and its alkoxy derivatives and their ability to modify a local blood flow in hemopoietic tissues have been comparatively studied in albino mice and rats. The correlation between these two parameters is nonlinear and may be approximated by a hyperbola equation. The correlation coefficient is - 0.88. A high radioprotective effect of serotonin and its derivatives is observed in the case of a three-fold decrease of the blood flow in the spleen

  10. Mathematical model of microbicidal flow dynamics and optimization of rheological properties for intra-vaginal drug delivery: Role of tissue mechanics and fluid rheology.

    Science.gov (United States)

    Anwar, Md Rajib; Camarda, Kyle V; Kieweg, Sarah L

    2015-06-25

    Topically applied microbicide gels can provide a self-administered and effective strategy to prevent sexually transmitted infections (STIs). We have investigated the interplay between vaginal tissue elasticity and the yield-stress of non-Newtonian fluids during microbicide deployment. We have developed a mathematical model of tissue deformation driven spreading of microbicidal gels based on thin film lubrication approximation and demonstrated the effect of tissue elasticity and fluid yield-stress on the spreading dynamics. Our results show that both elasticity of tissue and yield-stress rheology of gel are strong determinants of the coating behavior. An optimization framework has been demonstrated which leverages the flow dynamics of yield-stress fluid during deployment to maximize retention while reaching target coating length for a given tissue elasticity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Caffeine and cardiovascular health.

    Science.gov (United States)

    Turnbull, Duncan; Rodricks, Joseph V; Mariano, Gregory F; Chowdhury, Farah

    2017-10-01

    This report evaluates the scientific literature on caffeine with respect to potential cardiovascular outcomes, specifically relative risks of total cardiovascular disease (CVD), coronary heart disease (CHD) and acute myocardial infarction (AMI), effects on arrhythmia, heart failure, sudden cardiac arrest, stroke, blood pressure, hypertension, and other biomarkers of effect, including heart rate, cerebral blood flow, cardiac output, plasma homocysteine levels, serum cholesterol levels, electrocardiogram (EKG) parameters, heart rate variability, endothelial/platelet function and plasma/urine catecholamine levels. Caffeine intake has been associated with a range of reversible and transient physiological effects broadly and cardiovascular effects specifically. This report attempts to understand where the delineations exist in caffeine intake and corresponding cardiovascular effects among various subpopulations. The available literature suggests that cardiovascular effects experienced by caffeine consumers at levels up to 600 mg/day are in most cases mild, transient, and reversible, with no lasting adverse effect. The point at which caffeine intake may cause harm to the cardiovascular system is not readily identifiable in part because data on the effects of daily intakes greater than 600 mg is limited. However, the evidence considered within this review suggests that typical moderate caffeine intake is not associated with increased risks of total cardiovascular disease; arrhythmia; heart failure; blood pressure changes among regular coffee drinkers; or hypertension in baseline populations. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Skin autofluorescence as proxy of tissue AGE accumulation is dissociated from SCORE cardiovascular risk score, and remains so after 3 years

    NARCIS (Netherlands)

    Tiessen, Ans H.; Jager, Willemein; ter Bogt, Nancy C. W.; Beltman, Frank W.; van der Meer, Klaas; Broer, Jan; Smit, Andries J.

    Background: Skin autofluorescence (SAF), as a proxy of AGE accumulation, is predictive of cardiovascular (CVD) complications in i.a. type 2 diabetes mellitus and renal failure, independently of most conventional CVD risk factors. The present exploratory substudy of the Groningen Overweight and

  13. Flow

    DEFF Research Database (Denmark)

    Knoop, Hans Henrik

    2006-01-01

    FLOW. Orden i hovedet på den fede måde Oplevelsesmæssigt er flow-tilstanden kendetegnet ved at man er fuldstændig involveret, fokuseret og koncentreret; at man oplever stor indre klarhed ved at vide hvad der skal gøres, og i hvilket omfang det lykkes; at man ved at det er muligt at løse opgaven...

  14. Transthoracic ultrasonic tissue indices identify patients with severe left anterior descending artery stenosis. Correlation with fractional flow reserve. Pilot study.

    Science.gov (United States)

    Dobrowolski, Piotr; Kowalski, Mirosław; Rybicka, Justyna; Lech, Agnieszka; Tyczyński, Paweł; Witkowski, Adam; Hoffman, Piotr

    2016-01-01

    The aim of this study was to evaluate the potential clinical application of ultrasonic tissue indices, with a focus on systolic strain (SS) and systolic strain rate (SSR) parameters derived from transthoracic echocardiography, in the assessment of left anterior descending artery (LAD) stenosis. The data of 30 patients with significant LAD stenosis were analysed. All patients underwent transthoracic echocardiography to obtain systolic myocardial velocity (Sm), longitudinal SS, and SSR from basal, mid, and apical segments of anterior and inferior walls in two-chamber apical view. Severity of LAD obstruction was measured by means of fractional flow reserve (FFR) during coronary catheterisation. Systolic velocities, strain, and strain rate measured in basal, middle, and apical segments of the anterior left ventricular (LV) wall were lower when compared to those obtained from the corresponding, i.e. unaffected, inferior LV wall. There was a significant correlation between FFR and the value of SS, SSR characterising the apical LV segment of the anterior wall (r = -0.583, p = 0.01; r = -0.598, p = 0.01, respectively). Moreover, we found significant correlation between FFR and Sm in the mid-segment of the LV anterior wall (r = 0.611, p = 0.009). We conclude that SS and SSR obtained from the apical segment of the anterior LV wall may be related to the severity of LAD stenosis.

  15. Effect of short-term scrotal hyperthermia on spermatological parameters, testicular blood flow and gonadal tissue in dogs.

    Science.gov (United States)

    Henning, H; Masal, C; Herr, A; Wolf, K; Urhausen, C; Beineke, A; Beyerbach, M; Kramer, S; Günzel-Apel, A-R

    2014-02-01

    The objective was to assess the effect of a short-term scrotal hyperthermia in dogs on quantitative and qualitative ejaculate parameters, testicular blood flow and testicular and epididymal histology. After a control period, the scrotum of seven normospermic adult beagle dogs was insulated with a self-made suspensory for 48 h. Nine weeks later, two animals were castrated, while in five animals, scrotal hyperthermia was repeated. Dogs were castrated either 10 or 40 days thereafter. In each phase of scrotal insulation, average scrotal surface temperature increased by 3.0°C. Semen was collected twice weekly throughout the experiment. Total sperm count did not change after the first hyperthermia, but it slightly decreased after the second (p heat stress. Chromatin stability of ejaculated spermatozoa as indicated by SCSA remained constant throughout the experiment. Perfusion characteristics of the gonads, that is, systolic peak velocity, pulsatility and resistance index at the marginal location of the testicular artery, did not change due to hyperthermia (p > 0.05). Histological examination of excised testes and epididymides for apoptotic (TUNEL and activated caspase-3) and proliferating cells (Ki-67 antigen) indicated only marginal effects of scrotal insulation on tissue morphology. In conclusion, a mild short-term scrotal hyperthermia in dogs does not cause substantial changes in sperm quantity and quality. In contrast to other species, canine testes and epididymides may have a higher competence to compensate such thermal stress. © 2013 Blackwell Verlag GmbH.

  16. Hemophilia as a defect of the tissue factor pathway of blood coagulation: Effect of factors VIII and IX on factor X activation in a continuous-flow reactor

    International Nuclear Information System (INIS)

    Repke, D.; Gemmell, C.H.; Guha, A.; Turitto, V.T.; Nemerson, Y.; Broze, G.J. Jr.

    1990-01-01

    The effect of factors VIII and IX on the ability of the tissue factor-factor VIIa complex to activate factor X was studied in a continuous-flow tubular enzyme reactor. Tissue factor immobilized in a phospholipid bilayer on the inner surface of the tube was exposed to a perfusate containing factors VIIa, VIII, IX, and X flowing at a wall shear rate of 57, 300, or 1130 sec -1 . The addition of factors VIII and IX at their respective plasma concentrations resulted in a further 2 endash-to 3 endash fold increase. The direct activation of factor X by tissue factor-factor VIIa could be virtually eliminated by the lipoprotein-associated coagulation inhibitor. These results suggest that the tissue factor pathway, mediated through factors VIII and IX, produces significant levels of factor Xa even in the presence of an inhibitor of the tissue factor-factor VIIa complex; moreover, the activation is dependent on local shear conditions. These findings are consistent both with a model of blood coagulation in which initiation of the system results from tissue factor and with the bleeding observed in hemophilia

  17. [Autophagy in the cardiovascular system].

    Science.gov (United States)

    Kheloufi, Marouane; Rautou, Pierre-Emmanuel; Boulanger, Chantal M

    2017-03-01

    Cardiovascular diseases are the leading cause of mortality worldwide. Studies regarding the role of autophagy in cardiac and vascular tissues have opened new therapeutic avenues to treat cardiovascular disorders. Altogether, these studies point out that autophagic activity needs to be maintained at an optimal level to preserve cardiovascular function. Reaching this goal constitutes a challenge for future efficient therapeutic strategies. The present review therefore highlights recent advances in the understanding of the role of autophagy in cardiovascular pathologies. © 2017 médecine/sciences – Inserm.

  18. Tachykinins and the cardiovascular system.

    Science.gov (United States)

    Walsh, David A; F McWilliams, Daniel

    2006-08-01

    The tachykinin family of vasoactive peptides comprises the neuropeptides substance P, neurokinin A and neurokinin B, and the newly discovered endokinins and hemokinins. Their cardiovascular effects are predominantly mediated by the family of neurokinin receptors. This review summarises the most recent advances in understanding the effects of tachykinins on the vasculature, and summarises their therapeutic potential. Tachykinins stimulate plasma extravasation, particularly acting through neurokinin-1 receptors in an endothelium-dependent manner. They therefore play prominent roles in tissue oedema and inflammation (called neurogenic inflammation). Pro-inflammatory effects of tachykinins are enhanced by their capacity to stimulate inflammatory cell recruitment, and to initiate angiogenesis. Tachykinins also regulate vascular tone and blood flow, although differences between species and between different vascular beds make this a highly complex area of research. They may relax vessels in some scenarios whilst inducing vasoconstriction in other situations, the state of the endothelium appearing to be of key importance. Tachykinins also modulate blood pressure and heart rate, acting both peripherally, and on the central nervous system. Cardiovascular effects of tachykinins and neurokinin receptors may be important therapeutic targets in diverse disorders such as pulmonary oedema, hypertension, pre-eclampsia, complex regional pain syndrome type 2, stroke and chronic inflammatory diseases such as arthritis. Sophisticated modelling of human disease is required to enable neurokinin receptor antagonists to achieve this therapeutic potential.

  19. Beta-3 adrenergic agonist, BRL-26830A, and alpha/beta blocker, arotinolol, markedly increase regional blood flow in the brown adipose tissue in anesthetized rats.

    Science.gov (United States)

    Takahashi, H; Yoshida, T; Nishimura, M; Nakanishi, T; Kondo, M; Yoshimura, M

    1992-09-01

    Regional vascular effects of some adrenergic agents, focussing on brown adipose tissue (BAT), were investigated using tracer microspheres with a reference sample method in the anesthetized rat. Intravenous injections of 0.5 mg/kg BRL-26830A, a beta 3-adrenergic agonist, increased heart rate, but changes in blood pressure and cardiac output were not significant. The drug decreased blood flow in the brain, the spleen and the kidneys, but markedly increased it in BAT. At 2 mg/kg, arotinolol, an alpha/beta-adrenergic blocker, decreased blood pressure by 20 mmHg and increased cardiac output by 95 ml/min/kg. It slightly but significantly decreased blood flow in the liver and the spleen, but markedly increased the flow in BAT. Acebutolol, a beta 1-adrenergic blocker, decreased blood flow in the liver, the spleen, the pancreas, the kidneys, the adrenals, the skeletal muscle and the skin. Bunazosin, an alpha 1-adrenergic blocker, decreased it in all organs and tissue expect the brain and BAT. The pattern of redistribution of blood flow by arotinolol was very similar to that caused by BRL-26830A. Acebutolol and bunazosin rather decreased the blood flow in the BAT. These results indicate that stimulation of beta 3-adrenergic receptors, in BAT results in vasodilation, and that arotinolol may bind to those beta 3-adrenergic receptors.

  20. Tissue Functioning and Remodeling in the Circulatory and Ventilatory Systems

    CERN Document Server

    Thiriet, Marc

    2013-01-01

    The volumes in this authoritative series present a multidisciplinary approach to modeling and simulation of flows in the cardiovascular and ventilatory systems, especially multiscale modeling and coupled simulations. Volume 5 is devoted to cells, tissues, and organs of the cardiovascular and ventilatory systems with an emphasis on mechanotransduction-based regulation of flow. The blood vessel wall is a living tissue that quickly reacts to loads applied on it by the flowing blood. In any segment of a blood vessel, the endothelial and smooth muscle cells can sense unusual time variations in small-magnitude wall shear stress and large-amplitude wall stretch generated by abnormal hemodynamic stresses. These cells respond with a short-time scale (from seconds to hours) to adapt the vessel caliber. Since such adaptive cell activities can be described using mathematical models, a key objective of this volume is to identify the mesoscopic agents and nanoscopic mediators required to derive adequate mathematical models...

  1. Growth Hormone (GH) and Cardiovascular System.

    Science.gov (United States)

    Caicedo, Diego; Díaz, Oscar; Devesa, Pablo; Devesa, Jesús

    2018-01-18

    This review describes the positive effects of growth hormone (GH) on the cardiovascular system. We analyze why the vascular endothelium is a real internal secretion gland, whose inflammation is the first step for developing atherosclerosis, as well as the mechanisms by which GH acts on vessels improving oxidative stress imbalance and endothelial dysfunction. We also report how GH acts on coronary arterial disease and heart failure, and on peripheral arterial disease, inducing a neovascularization process that finally increases flow in ischemic tissues. We include some preliminary data from a trial in which GH or placebo is given to elderly people suffering from critical limb ischemia, showing some of the benefits of the hormone on plasma markers of inflammation, and the safety of GH administration during short periods of time, even in diabetic patients. We also analyze how Klotho is strongly related to GH, inducing, after being released from the damaged vascular endothelium, the pituitary secretion of GH, most likely to repair the injury in the ischemic tissues. We also show how GH can help during wound healing by increasing the blood flow and some neurotrophic and growth factors. In summary, we postulate that short-term GH administration could be useful to treat cardiovascular diseases.

  2. Growth Hormone (GH) and Cardiovascular System

    Science.gov (United States)

    Díaz, Oscar; Devesa, Pablo

    2018-01-01

    This review describes the positive effects of growth hormone (GH) on the cardiovascular system. We analyze why the vascular endothelium is a real internal secretion gland, whose inflammation is the first step for developing atherosclerosis, as well as the mechanisms by which GH acts on vessels improving oxidative stress imbalance and endothelial dysfunction. We also report how GH acts on coronary arterial disease and heart failure, and on peripheral arterial disease, inducing a neovascularization process that finally increases flow in ischemic tissues. We include some preliminary data from a trial in which GH or placebo is given to elderly people suffering from critical limb ischemia, showing some of the benefits of the hormone on plasma markers of inflammation, and the safety of GH administration during short periods of time, even in diabetic patients. We also analyze how Klotho is strongly related to GH, inducing, after being released from the damaged vascular endothelium, the pituitary secretion of GH, most likely to repair the injury in the ischemic tissues. We also show how GH can help during wound healing by increasing the blood flow and some neurotrophic and growth factors. In summary, we postulate that short-term GH administration could be useful to treat cardiovascular diseases. PMID:29346331

  3. Interrelationships Among Flow-Mediated Vasodilation, Nitroglycerine-Induced Vasodilation, Baseline Brachial Artery Diameter, Hyperemic Shear Stress, and Cardiovascular Risk Factors.

    Science.gov (United States)

    Maruhashi, Tatsuya; Iwamoto, Yumiko; Kajikawa, Masato; Oda, Nozomu; Kishimoto, Shinji; Matsui, Shogo; Hashimoto, Haruki; Aibara, Yoshiki; Yusoff, Farina Mohamad; Hidaka, Takayuki; Kihara, Yasuki; Chayama, Kazuaki; Noma, Kensuke; Nakashima, Ayumu; Goto, Chikara; Hida, Eisuke; Higashi, Yukihito

    2017-12-29

    Flow-mediated vasodilation (FMD) of the brachial artery has been used for the assessment of endothelial function. Considering the mechanism underlying the vasodilatory response of the brachial artery to reactive hyperemia, hyperemic shear stress (HSS), a stimulus for FMD; nitroglycerine-induced vasodilation (NID), an index of endothelium-independent vasodilation; and baseline brachial artery diameter (BAD) are also involved in vasodilatory response. The purpose of this study was to investigate the interrelationships among FMD, HSS, NID, baseline BAD, and cardiovascular risk factors. We measured FMD, HSS, NID, and baseline BAD simultaneously in 1033 participants (633 men and 400 women; mean age: 58.6±17.0 years). Framingham risk score was negatively correlated with FMD, HSS, and NID and was positively correlated with baseline BAD. HSS and NID were positively correlated with FMD, and baseline BAD was negatively correlated with FMD. In participants with normal NID, FMD was correlated with HSS, NID, and baseline BAD, all of which were independent variables of FMD in multivariate analysis. In participants with impaired NID, FMD was correlated with NID and baseline BAD, both of which were independent variables of FMD in multivariate analysis, but there was no association between FMD and HSS. NID and baseline BAD were independent variables of FMD regardless of the status of endothelium-independent vasodilation, whereas there was a significant association between FMD and HSS in participants with normal NID but not in those with impaired NID. The influence of HSS on FMD seems to be dependent on the status of endothelium-independent vasodilation. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  4. A Decrease in Spatially Resolved Near-Infrared Spectroscopy-Determined Frontal Lobe Tissue Oxygenation by Phenylephrine Reflects Reduced Skin Blood Flow

    DEFF Research Database (Denmark)

    Ogoh, Shigehiko; Sato, Kohei; Okazaki, Kazunobu

    2014-01-01

    O2. METHODS: We measured ScO2 and internal and external carotid as well as vertebral artery blood flow in 7 volunteers (25 [SD 4] years) by duplex ultrasonography during IV infusion of phenylephrine, together with middle cerebral artery mean blood velocity, forehead skin blood flow, and mean arterial...... blood pressure. RESULTS: During phenylephrine infusion, mean arterial blood pressure increased, while ScO2 decreased by -19% ± 3% (mean ± SE; P = 0.0005). External carotid artery (-27.5% ± 3.0%) and skin blood flow (-25.4% ± 7.8%) decreased in response to phenylephrine administration......BACKGROUND: Spatially resolved near-infrared spectroscopy-determined frontal lobe tissue oxygenation (ScO2) is reduced with administration of phenylephrine, while cerebral blood flow may remain unaffected. We hypothesized that extracranial vasoconstriction explains the effect of phenylephrine on Sc...

  5. Simultaneous, quantitative measurement of local blood flow and glucose utilization in tissue samples in normal and injured feline brain.

    Science.gov (United States)

    DeWitt, D S; Yuan, X Q; Becker, D P; Hayes, R L

    1988-01-01

    Cerebral blood flow (CBF) and local cerebral glucose utilization (LCGU) were measured using radioactive microspheres and [14C]2-deoxyglucose, respectively, in 26 brain regions in control animals (n = 8) and in animals (n = 4) sustaining low-level experimental brain injury. Examination of the initial (resting) CBF measurement in the uninjured cats revealed two subgroups with significantly (p less than 0.01) different CBF levels. In uninjured cats with normal CBF levels (33.4 +/- 1.8 ml/100 g/min) there was a close linear relationship between CBF and LCGU (n = 0.71, p less than 0.01). In contrast, the remainder of the uninjured cats exhibited abnormally high levels of CBF (72.6 +/- 9.9 ml/100 g/min) and the absence of a close relationship between CBF and LCGU (r = 0.27). One hour following low-level (2.0 atm) fluid percussion brain injury, CBF was increased and LCGU was decreased, though not significantly. The relationship between CBF and LCGU remained intact (r = 0.66, p less than 0.01) in most brain regions. However, the relationship between CBF and LCGU in the hippocampus differed significantly from the relationship between the two parameters in the rest of the brain. Thus, the use of the radioactive microsphere method for CBF measurements allows multiple measurements of CBF and permits the assessment of the status of the cerebral vasculature prior to experimental manipulations such as traumatic brain injury. In view of our current findings of an abnormal relationship between CBF and LCGU in cats with high resting CBF levels, this is an important advantage. In addition, the combination of the microsphere and 2-DG techniques within the same tissue samples allows for the investigation of the effects of traumatic injury on the important relationship between CBF and LCGU.

  6. Cardiovascular Deconditioning

    Science.gov (United States)

    Charles, John B.; Fritsch-Yelle, Janice M.; Whitson, Peggy A.; Wood, Margie L.; Brown, Troy E.; Fortner, G. William

    1999-01-01

    Spaceflight causes adaptive changes in cardiovascular function that may deleteriously affect crew health and safety. Over the last three decades, symptoms of cardiovascular changes have ranged from postflight orthostatic tachycardia and decreased exercise capacity to serious cardiac rhythm disturbances during extravehicular activities (EVA). The most documented symptom of cardiovascular dysfunction, postflight orthostatic intolerance, has affected a significant percentage of U.S. Space Shuttle astronauts. Problems of cardiovascular dysfunction associated with spaceflight are a concern to NASA. This has been particularly true during Shuttle flights where the primary concern is the crew's physical health, including the pilot's ability to land the Orbiter, and the crew's ability to quickly egress and move to safety should a dangerous condition arise. The study of astronauts during Shuttle activities is inherently more difficult than most human research. Consequently, sample sizes have been small and results have lacked consistency. Before the Extended Duration Orbiter Medical Project (EDOMP), there was a lack of normative data on changes in cardiovascular parameters during and after spaceflight. The EDOMP for the first time allowed studies on a large enough number of subjects to overcome some of these problems. There were three primary goals of the Cardiovascular EDOMP studies. The first was to establish, through descriptive studies, a normative data base of cardiovascular changes attributable to spaceflight. The second goal was to determine mechanisms of cardiovascular changes resulting from spaceflight (particularly orthostatic hypotension and cardiac rhythm disturbances). The third was to evaluate possible countermeasures. The Cardiovascular EDOMP studies involved parallel descriptive, mechanistic, and countermeasure evaluations.

  7. Evaluation of a new high power, wide separation laser Doppler probe : Potential measurement of deeper tissue blood flow

    NARCIS (Netherlands)

    Clough, Geraldine; Chipperfield, Andrew; Byrne, Christopher; de Mul, Frits; Gush, Rodney

    Objective: To compare the output from a novel high power, wide separation laser Doppler flow probe (DP1-V2-HP, 4 mm, with IRLD20) with that of a standard flow probe (DP1-V2, 0.5 mm, with DRT4) (Moor UK) and to explore its potential for use in the noninvasive measurement of blood flow in deeper

  8. Variation in blood flow of supporting tissue during use of mandibular complete dentures with hard acrylic resin base and soft relining: a preliminary study.

    Science.gov (United States)

    Kocabalkan, Engin; Turgut, Mehmet

    2005-01-01

    This study investigated the influence of hard and resilient polymerized acrylic resin base materials on the blood flow of the supporting underlying mucosa of mandibular denture wearers during different denture-wearing periods. Measurements were carried out on 20 complete denture wearers, 10 with hard bases and 10 with soft ones. The mucosal blood flow underlying the dentures was measured bilaterally in the canine and molar regions using a laser Doppler flowmeter. Baseline measurements were performed before denture wearing and after the dentures were worn for 1 week, 1 month, 3 months, and 6 months. Mean blood flow to the mucosa after 1 week was significantly lower in the measured regions than that obtained before the dentures were worn. Blood flow in the canine region returned to almost normal levels 6 months after beginning to wear complete dentures. However, blood flow in the molar region of the denture wearers in the hard base group increased after 6 months, whereas blood flow values did not return to the levels recorded before denture insertion in the soft lining group. It appears that wearing dentures hinders blood flow to denture-supporting tissues, even when soft liners are used.

  9. Fully-automated fibroglandular tissue segmentation and volumetric density estimation in breast MRI by integrating a continuous max-flow model and a likelihood atlas

    Science.gov (United States)

    Wu, Shandong; Weinstein, Susan P.; Conant, Emily F.; Kontos, Despina

    2013-02-01

    Studies suggest that the relative amount of fibroglandular tissue in the breast as quantified in breast MRI can be predictive of the risk for developing breast cancer. Automated segmentation of the fibroglandular tissue from breast MRI data could therefore be an essential component in quantitative risk assessment. In this work we propose a new fullyautomated 3D segmentation algorithm, namely the continuous max-flow (CMF)-Atlas method, to estimate the volumetric amount of fibroglandular tissue in breast MRI. Our method goes through a first step of applying a continuous max-flow model in the MR image intensity space to produce an initial voxel-wise likelihood map of being fibroglandular tissue. Then we further incorporate an a-priori learned fibroglandular tissue likelihood atlas to refine the initial likelihood map to achieve enhanced segmentation, from which the relative (e.g., percent) volumetric amount of fibroglandular tissue (FT%) in the breast is computed. Our method is evaluated by a representative dataset of 16 3D bilateral breast MRI scans (32 breasts, 896 tomographic MR slices in total). A high correlation (r=0.95) is achieved in FT% estimation, and the overall averaged spatial segmentation agreement is 0.77 in terms of Dice's coefficient, between the automated segmentation and the manual segmentation obtained from an experienced breast imaging radiologist. The automated segmentation method also runs time-efficiently at ~1 minute for each 3D MR scan (56 slices), compared to ~15 minutes needed for manual segmentation. Our method can serve as an effective tool for processing large scale clinical breast MR datasets for quantitative fibroglandular tissue estimation.

  10. Business Process Flow Diagrams in Tissue Bank Informatics System Design, and Identification and Communication of Best Practices: The Pharmaceutical Industry Experience.

    Science.gov (United States)

    McDonald, Sandra A; Velasco, Elizabeth; Ilasi, Nicholas T

    2010-12-01

    Pfizer, Inc.'s Tissue Bank, in conjunction with Pfizer's BioBank (biofluid repository), endeavored to create an overarching internal software package to cover all general functions of both research facilities, including sample receipt, reconciliation, processing, storage, and ordering. Business process flow diagrams were developed by the Tissue Bank and Informatics teams as a way of characterizing best practices both within the Bank and in its interactions with key internal and external stakeholders. Besides serving as a first step for the software development, such formalized process maps greatly assisted the identification and communication of best practices and the optimization of current procedures. The diagrams shared here could assist other biospecimen research repositories (both pharmaceutical and other settings) for comparative purposes or as a guide to successful informatics design. Therefore, it is recommended that biorepositories consider establishing formalized business process flow diagrams for their laboratories, to address these objectives of communication and strategy.

  11. Mechanisms for the control of local tissue blood flow during thermal interventions: influence of temperature‐dependent ATP release from human blood and endothelial cells

    Science.gov (United States)

    Chiesa, Scott T.; Trangmar, Steven J.; Ali, Leena; Lotlikar, Makrand D.; González‐Alonso, José

    2017-01-01

    New Findings What is the central question of this study? Skin and muscle blood flow increases with heating and decreases with cooling, but the temperature‐sensitive mechanisms underlying these responses are not fully elucidated. What is the main finding and its importance? We found that local tissue hyperaemia was related to elevations in ATP release from erythrocytes. Increasing intravascular ATP augmented skin and tissue perfusion to levels equal or above thermal hyperaemia. ATP release from isolated erythrocytes was altered by heating and cooling. Our findings suggest that erythrocytes are involved in thermal regulation of blood flow via modulation of ATP release. Local tissue perfusion changes with alterations in temperature during heating and cooling, but the thermosensitivity of the vascular ATP signalling mechanisms for control of blood flow during thermal interventions remains unknown. Here, we tested the hypotheses that the release of the vasodilator mediator ATP from human erythrocytes, but not from endothelial cells or other blood constituents, is sensitive to both increases and reductions in temperature and that increasing intravascular ATP availability with ATP infusion would potentiate thermal hyperaemia in limb tissues. We first measured blood temperature, brachial artery blood flow and plasma [ATP] during passive arm heating and cooling in healthy men and found that they increased by 3.0 ± 1.2°C, 105 ± 25 ml min−1 °C−1 and twofold, respectively, (all P tissue perfusion to levels equal or above thermal hyperaemia. In isolated erythrocyte samples exposed to different temperatures, ATP release increased 1.9‐fold from 33 to 39°C (P tissue perfusion with limb heating are associated with elevations in ATP release from erythrocytes, but not from endothelial cells or other blood constituents. Erythrocyte ATP release is also sensitive to temperature reductions, suggesting that erythrocytes may function as thermal sensors and ATP

  12. Mechanisms for the control of local tissue blood flow during thermal interventions: influence of temperature-dependent ATP release from human blood and endothelial cells.

    Science.gov (United States)

    Kalsi, Kameljit K; Chiesa, Scott T; Trangmar, Steven J; Ali, Leena; Lotlikar, Makrand D; González-Alonso, José

    2017-02-01

    What is the central question of this study? Skin and muscle blood flow increases with heating and decreases with cooling, but the temperature-sensitive mechanisms underlying these responses are not fully elucidated. What is the main finding and its importance? We found that local tissue hyperaemia was related to elevations in ATP release from erythrocytes. Increasing intravascular ATP augmented skin and tissue perfusion to levels equal or above thermal hyperaemia. ATP release from isolated erythrocytes was altered by heating and cooling. Our findings suggest that erythrocytes are involved in thermal regulation of blood flow via modulation of ATP release. Local tissue perfusion changes with alterations in temperature during heating and cooling, but the thermosensitivity of the vascular ATP signalling mechanisms for control of blood flow during thermal interventions remains unknown. Here, we tested the hypotheses that the release of the vasodilator mediator ATP from human erythrocytes, but not from endothelial cells or other blood constituents, is sensitive to both increases and reductions in temperature and that increasing intravascular ATP availability with ATP infusion would potentiate thermal hyperaemia in limb tissues. We first measured blood temperature, brachial artery blood flow and plasma [ATP] during passive arm heating and cooling in healthy men and found that they increased by 3.0 ± 1.2°C, 105 ± 25 ml min -1  °C -1 and twofold, respectively, (all P tissue perfusion to levels equal or above thermal hyperaemia. In isolated erythrocyte samples exposed to different temperatures, ATP release increased 1.9-fold from 33 to 39°C (P tissue perfusion with limb heating are associated with elevations in ATP release from erythrocytes, but not from endothelial cells or other blood constituents. Erythrocyte ATP release is also sensitive to temperature reductions, suggesting that erythrocytes may function as thermal sensors and ATP signalling generators for

  13. Exploring the feasibility of multi-site flow cytometric processing of gut associated lymphoid tissue with centralized data analysis for multi-site clinical trials.

    Science.gov (United States)

    McGowan, Ian; Anton, Peter A; Elliott, Julie; Cranston, Ross D; Duffill, Kathryn; Althouse, Andrew D; Hawkins, Kevin L; De Rosa, Stephen C

    2015-01-01

    The purpose of this study was to determine whether the development of a standardized approach to the collection of intestinal tissue from healthy volunteers, isolation of gut associated lymphoid tissue mucosal mononuclear cells (MMC), and characterization of mucosal T cell phenotypes by flow cytometry was sufficient to minimize differences in the normative ranges of flow parameters generated at two trial sites. Forty healthy male study participants were enrolled in Pittsburgh and Los Angeles. MMC were isolated from rectal biopsies using the same biopsy acquisition and enzymatic digestion protocols. As an additional comparator, peripheral blood mononuclear cells (PBMC) were collected from the study participants. For quality control, cryopreserved PBMC from a single donor were supplied to both sites from a central repository (qPBMC). Using a jointly optimized standard operating procedure, cells were isolated from tissue and blood and stained with monoclonal antibodies targeted to T cell phenotypic markers. Site-specific flow data were analyzed by an independent center which analyzed all data from both sites. Ranges for frequencies for overall CD4+ and CD8+ T cells, derived from the qPBMC samples, were equivalent at both UCLA and MWRI. However, there were significant differences across sites for the majority of T cell activation and memory subsets in qPBMC as well as PBMC and MMC. Standardized protocols to collect, stain, and analyze MMC and PBMC, including centralized analysis, can reduce but not exclude variability in reporting flow data within multi-site studies. Based on these data, centralized processing, flow cytometry, and analysis of samples may provide more robust data across multi-site studies. Centralized processing requires either shipping of fresh samples or cryopreservation and the decision to perform centralized versus site processing needs to take into account the drawbacks and restrictions associated with each method.

  14. Exploring the feasibility of multi-site flow cytometric processing of gut associated lymphoid tissue with centralized data analysis for multi-site clinical trials.

    Directory of Open Access Journals (Sweden)

    Ian McGowan

    Full Text Available The purpose of this study was to determine whether the development of a standardized approach to the collection of intestinal tissue from healthy volunteers, isolation of gut associated lymphoid tissue mucosal mononuclear cells (MMC, and characterization of mucosal T cell phenotypes by flow cytometry was sufficient to minimize differences in the normative ranges of flow parameters generated at two trial sites. Forty healthy male study participants were enrolled in Pittsburgh and Los Angeles. MMC were isolated from rectal biopsies using the same biopsy acquisition and enzymatic digestion protocols. As an additional comparator, peripheral blood mononuclear cells (PBMC were collected from the study participants. For quality control, cryopreserved PBMC from a single donor were supplied to both sites from a central repository (qPBMC. Using a jointly optimized standard operating procedure, cells were isolated from tissue and blood and stained with monoclonal antibodies targeted to T cell phenotypic markers. Site-specific flow data were analyzed by an independent center which analyzed all data from both sites. Ranges for frequencies for overall CD4+ and CD8+ T cells, derived from the qPBMC samples, were equivalent at both UCLA and MWRI. However, there were significant differences across sites for the majority of T cell activation and memory subsets in qPBMC as well as PBMC and MMC. Standardized protocols to collect, stain, and analyze MMC and PBMC, including centralized analysis, can reduce but not exclude variability in reporting flow data within multi-site studies. Based on these data, centralized processing, flow cytometry, and analysis of samples may provide more robust data across multi-site studies. Centralized processing requires either shipping of fresh samples or cryopreservation and the decision to perform centralized versus site processing needs to take into account the drawbacks and restrictions associated with each method.

  15. Impaired autoregulation of blood flow in subcutaneous tissue of long-term type 1 (insulin-dependent) diabetic patients with microangiopathy

    DEFF Research Database (Denmark)

    Kastrup, J; Nørgaard, T; Parving, H H

    1985-01-01

    Autoregulation of blood flow in subcutaneous tissue was studied at the level of the lateral malleolus in eight long-term Type 1 (insulin-dependent) diabetic patients with clinical microangiopathy, eight short-term Type 1 diabetic patients without clinical microangiopathy and seven healthy control...... subjects. Blood flow was measured by the local 133Xenon washout technique. Mean arterial blood pressure was reduced by a maximum of 23 mmHg by elevating the limb above heart level and elevating to a maximum of 70 mmHg by head-up tilt; in the latter position venous pressure was kept constant and low...... by activation of the leg muscle vein pump (heel raising). Mean arterial blood pressure was thus varied between 60 and 160 mmHg. In normal and short-term diabetic subjects blood flow remained within 10% of control values during the changes in arterial blood pressure. In six of the eight Type 1 diabetic patients...

  16. Cardiovascular responses of snakes to hypergravity

    Science.gov (United States)

    Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.; Rosenberg, H. I.

    1997-01-01

    Snakes have provided useful vertebrate models for understanding circulatory adaptation to gravity, attributable to their elongate body shape and evolutionary diversificaton in terms of ecology and behavior. Recently we have studied cardiovascular responses of snakes to hypergravic acceleration forces produced acutely in the head-to-tail direction (+Gz) on a short-arm centrifuge. Snakes were held in a nearly straight position within a horizontal plastic tube and subjected to a linear force gradient during acceleration. Carotid blood flow provided an integrated measure of cardiovascular performance. Thus, cardiovascular tolerance of snakes to stepwise increments of Gz was measured as the caudal Gz force at which carotid blood flow ceased. Tolerance to increasing Gz varies according to adaptive evolutionary history inferred from the ecology and behavior of species. With respect to data for six species we investigated, multiple regression analysis demonstrates that Gz tolerance correlates with gravitational habitat, independently of body length. Relative to aquatic and non-climbing species, carotid blood flow is better maintained in arboreal or scansorial species, which tolerate hypergravic forces of +2 to +3.5 Gz. Additionally, semi-arboreal rat snakes (Elaphe obsoleta) exhibit plasticity of responses to long-term, intermittent +1.5 Gz stress. Compared to non-acclimated controls, acclimated snakes show greater increases of heart rate during head-up tilt or acceleration, greater sensitivity of arterial pressure to circulating catecholamines, higher blood levels of prostaglandin ratios favorable to maintenance of arterial blood pressure, and medial hypertrophy in major arteries and veins. As in other vertebrates, Gz tolerance of snakes is enhanced by acclimation, high arterial pressure, comparatively large blood volume, and body movements. Vascular studies of snakes suggest the importance to acclimation of local responses involving vascular tissue, in addition to

  17. Cardiovascular radiology

    International Nuclear Information System (INIS)

    VanAman, M.; Mueller, C.F.

    1985-01-01

    Soon after Roentgen documented the uses of x-rays in 1895, fluoroscopic and film evaluation of the heart began. Even today the chest roentgenogram remains one of the first and most frequently used studies for the evaluation of the normal and abnormal heart and great vessels. This chapter gives an overview of plain film evaluation of the cardiovascular system and follow up with comments on the newer imaging modalities of computed tomography, and digital subtraction angiography, in the cardiovascular disease workup. The authors present an evaluation of plain films of the chest, which remains their most cost effective, available, simple, and reliable initial screening tool in the evaluation of cardiovascular disease

  18. Simultaneous multi-depth assessment of tissue oxygen saturation in thenar and forearm using near-infrared spectroscopy during a simple cardiovascular challenge

    NARCIS (Netherlands)

    Bezemer, Rick; Karemaker, John M.; Klijn, Eva; Martin, Daniel; Mitchell, Kay; Grocott, Mike; Heger, Michal; Ince, Can

    2009-01-01

    INTRODUCTION: Hypovolemia and hypovolemic shock are life-threatening conditions that occur in numerous clinical scenarios. Near-infrared spectroscopy (NIRS) has been widely explored, successfully and unsuccessfully, in an attempt to use it as an early detector of hypovolemia by measuring tissue

  19. Inflammatory characteristics of distinct abdominal adipose tissue depots relate differently to metabolic risk factors for cardiovascular disease Distinct fat depots and vascular risk factors

    NARCIS (Netherlands)

    Kranendonk, Mariette E. G.; van Herwaarden, Joost A.; Stupkova, Tereza; de Jager, Wilco; Vink, Aryan; Moll, Frans L.; Kalkhoven, Eric; Visseren, Frank L. J.

    Objective: Abdominal obesity is associated with insulin resistance and metabolic syndrome. However, specific contributions of distinct adipose tissue (AT) depots to metabolic complications of obesity are still unclear. In this study, the inflammatory profile of four distinct abdominal AT-depots and

  20. Effect of sodium nitroprusside-induced hypotension on the blood flow in subcutaneous and intramuscular BT4An tumors and normal tissues in rats

    International Nuclear Information System (INIS)

    Krossnes, Baard Kronen; Mella, Olav; Tyssebotn, Ingvald

    1996-01-01

    Purpose: To examine the effect of infusion of the vasodilator sodium nitroprusside (SNP) on the blood flow in normal tissues and BT 4 An tumors growing subcutaneously or intramusculary in BD IX rats. Methods and Materials: Sodium nitroprusside was given as a continuous intravenous infusion to keep the mean arterial pressure stable at 60 mmHg. The cardiac output, organ blood flow, and perfusion of the BT 4 An tumors were measured by injection of radiolabelled microspheres at control conditions and after 20 min SNP infusion in each animal. Two series of experiments were performed with two anesthetics with different mechanisms of action, Inactin and the midazolam-fentanyl-fluanisone combination (MFF), to secure reliable conclusions. Results: Cardiac output, heart rate, and blood flow to the skeletal muscles, heart, and liver increased during SNP infusion in either anesthetic group. In the kidneys and particularly in the skin, decreased blood flow by SNP was observed. When located subcutaneously on the foot, the blood flow in the tumor fell to 23.4% and 21.4% of the control values in the MFF- and Inactin-anesthetized animals, respectively. This was accompanied by a similar fall in the blood flow in the foot (tumor bed) itself. In the intramuscular tumor the blood flow fell to 24.8% of the control value in the MFF group, whereas the corresponding figure was 36.2% in the Inactin group. In the surrounding muscle (tumor bed) the blood flow increased significantly, most pronounced in the MFF experiment, where it was tripled. Conclusion: The fall in the tumor perfusion by SNP may be exploited therapeutically to increase the tumor temperature during hyperthermia. Predominant heating of the tumor compared to the tumor bed can be expected if the tumor is growing in or near skeletal muscles

  1. Microwave Ablation Using Four-Tine Antenna: Effects of Blood Flow Velocity, Vessel Location, and Total Displacement on Porous Hepatic Cancer Tissue

    Directory of Open Access Journals (Sweden)

    Montree Chaichanyut

    2016-01-01

    Full Text Available This research is concerned with microwave ablation analyses using a 2.45 GHz four-tine (4T antenna for hepatic cancer tissue. In the study, three-dimensional finite-element models were utilized to examine the tissue temperature distributions during and after MW ablation. A preliminary study was first carried out with regard to the specific absorption rates along the 4T antenna insertion depths and the temperature distributions inside the solid and porous liver models with either 3 cm-in-diameter tumor or 5 cm-in-diameter tumor. Based on the preliminary results, the porous models were further examined for the effect of varying blood flow velocities (0–200 cm/s with a 1 cm-in-diameter blood vessel next to the antenna and also for the effect of vessel-antenna locations (0, 0.8, and 1.3 cm with a constant blood flow velocity of 16.7 cm/s. All scenarios were simulated under temperature-controlled mode (90°C. The findings revealed that the blood flow velocity and vessel location influence the ablation effectiveness and that increased blood flow inhibits heat transfer to the vessel wall. At the nearest and farthest vessel-antenna locations (0 and 1.3 cm, approximately 90.3% and 99.55% of the cancer cells were eradicated except for the areas adjacent to the vessel. In addition, total tissue thermal displacement is 5.9 mm which is 6.59% of the total length of the overall model.

  2. The role of visceral and subcutaneous adipose tissue measurements and their ratio by magnetic resonance imaging in subjects with prediabetes, diabetes and healthy controls from a general population without cardiovascular disease.

    Science.gov (United States)

    Storz, Corinna; Heber, Sophia D; Rospleszcz, Susanne; Machann, Jürgen; Sellner, Sabine; Nikolaou, Konstantin; Lorbeer, Roberto; Gatidis, Sergios; Elser, Stefanie; Peters, Annette; Schlett, Christopher L; Bamberg, Fabian

    2018-02-19

    To study the relationship of area- and volumetric-based visceral and subcutaneous adipose tissue (VAT and SAT) by MRI and their ratio in subjects with impaired glucose metabolism from the general population. Subjects from a population-based cohort with established prediabetes, diabetes and healthy controls without prior cardiovascular diseases underwent 3 T MRI. VAT and SAT were assessed as total volume and area on a single slice, and their ratio (VAT/SAT) was calculated. Clinical covariates and cardiovascular risk factors, such as hypertension and glycemic state were assessed in standardized fashion. Univariate and adjusted analyses were conducted. Among 384 subjects (age: 56.2 ± 9.2 years, 58.1% male) with complete MRI data available, volumetric and single-slice VAT, SAT and VAT/SAT ratio were strongly correlated (all >r = 0.89). Similarly, VAT/SAT volume ratio was strongly correlated with VAT volume but not with SAT (r = 0.72 and r = -0.21, respectively). Significant higher levels of VAT, SAT and VAT/SAT ratio were found in subjects with impaired glucose metabolism (all p ≤ 0.01). After adjustment for potential cardiovascular confounders, VAT volume and VAT/SAT volume ratio remained significantly higher in subjects with impaired glucose metabolism (VAT volume = 6.9 ± 2.5 l and 3.4 ± 2.3 l; VAT/SAT volume ratio = 0.82 ± 0.34 l and 0.49 ± 0.29 l in patients with diabetes and controls, respectively, all p VAT/SAT volume ratio with increasing body mass index and waist circumference (p VAT volume and VAT/SAT volume ratio are associated with impaired glucose metabolism, independent of cardiovascular risk factors or MRI-based quantification technique, with a decreasing effect of VAT/SAT volume ratio in obese subjects. Advances in knowledge: Quantification of VAT volume and VAT/SAT volume ratio by MRI represents a reproducable biomarker associated with cardiometabolic risk factors in subjects with impaired glucose metabolism, while the association of VAT

  3. Basic study of intrinsic elastography: Relationship between tissue stiffness and propagation velocity of deformation induced by pulsatile flow

    Science.gov (United States)

    Nagaoka, Ryo; Iwasaki, Ryosuke; Arakawa, Mototaka; Kobayashi, Kazuto; Yoshizawa, Shin; Umemura, Shin-ichiro; Saijo, Yoshifumi

    2015-07-01

    We proposed an estimation method for a tissue stiffness from deformations induced by arterial pulsation, and named this proposed method intrinsic elastography (IE). In IE, assuming that the velocity of the deformation propagation in tissues is closely related to the stiffness, the propagation velocity (PV) was estimated by spatial compound ultrasound imaging with a high temporal resolution of 1 ms. However, the relationship between tissue stiffness and PV has not been revealed yet. In this study, the PV of the deformation induced by the pulsatile pump was measured by IE in three different poly(vinyl alcohol) (PVA) phantoms of different stiffnesses. The measured PV was compared with the shear wave velocity (SWV) measured by shear wave imaging (SWI). The measured PV has trends similar to the measured SWV. These results obtained by IE in a healthy male show the possibility that the mechanical properties of living tissues could be evaluated by IE.

  4. Formation of the peak amplitude of blood flow oscillations at a frequency of 0.1 Hz in the human cardiovascular system by the noise effect on the heart

    Science.gov (United States)

    Grinevich, Andrey A.; Tankanag, Arina V.; Chemeris, Nikolay K.

    2017-04-01

    In the framework of our previous hypothesis about the participation of structural and hydrodynamic properties of the vascular bed in the formation of the 0.1-Hz component of blood flow oscillations in the human cardiovascular system and on the basis of the reduced hydrodynamic model, the role of additive stochastic perturbations of the operation of the single-chamber pump that simulates the heart was investigated. It was shown that aperiodic noise modulation of the rigidity of the walls of the pump or its valves generates low-frequency oscillations of pressure of arterial vascular bed with the spectral components at a frequency close to 0.1 Hz.

  5. Urotensin II in cardiovascular regulation

    Directory of Open Access Journals (Sweden)

    Fraser D Russell

    2008-08-01

    Full Text Available Fraser D RussellSchool of Health and Sport Sciences, Faculty of Science, Health and Education, University of the Sunshine Coast, Sippy Downs, Queensland, AustraliaAbstract: Cardiovascular function is modulated by neuronal transmitters, circulating hormones, and factors that are released locally from tissues. Urotensin II (UII is an 11 amino acid peptide that stimulates its’ obligatory G protein coupled urotensin II receptors (UT to modulate cardiovascular function in humans and in other animal species, and has been implicated in both vasculoprotective and vasculopathic effects. For example, tissue and circulating concentrations of UII have been reported to increase in some studies involving patients with atherosclerosis, heart failure, hypertension, preeclampsia, diabetes, renal disease and liver disease, raising the possibility that the UT receptor system is involved in the development and/or progression of these conditions. Consistent with this hypothesis, administration of UT receptor antagonists to animal models of cardiovascular disease have revealed improvements in cardiovascular remodelling and hemodynamics. However, recent studies have questioned this contributory role of UII in disease, and have instead postulated a protective effect on the cardiovascular system. For example, high concentrations of circulating UII correlated with improved clinical outcomes in patients with renal disease or myocardial infarction. The purpose of this review is to consider the regulation of the cardiovascular system by UII, giving consideration to methodologies for measurement of plasma concentrations, sites of synthesis and triggers for release.Keywords: urotensin II, cardiovascular disease, heart failure, hypertension

  6. Arterial aging and arterial disease : interplay between central hemodynamics, cardiac work, and organ flow-implications for CKD and cardiovascular disease

    NARCIS (Netherlands)

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

    Cardiovascular disease is an important cause of morbidity and mortality in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD). All epidemiological studies have clearly shown that accelerated arterial and cardiac aging is characteristic of these populations. Arterial

  7. Effect of steel and teflon infusion catheters on subcutaneous adipose tissue blood flow and infusion counter pressure in humans

    DEFF Research Database (Denmark)

    Højbjerre, Lise; Skov-Jensen, Camilla; Kaastrup, Peter

    2009-01-01

    BACKGROUND: Subcutaneous tissue is an important target for drug deposition or infusion. A local trauma may induce alterations in local microcirculation and diffusion barriers with consequences for drug bioavailability. We examined the influence of infusion catheters' wear time on local...... microcirculation and infusion counter pressure. METHODS: One steel catheter and one Teflon (Dupont, Wilmington, DE) catheter were inserted in subcutaneous, abdominal adipose tissue (SCAAT) in 10 healthy, lean men. The catheters were infused with isotonic saline at a rate of 10 microL/h for 48 h. Another steel...... catheter and a Teflon catheter were inserted contralateral to the previous catheters after 48 h. The infusion counter pressure was measured during a basal infusion rate followed by a bolus infusion. The measurements during a basal rate infusion were repeated after the bolus infusion. Adipose tissue blood...

  8. Cardiovascular genomics.

    Science.gov (United States)

    Wung, Shu-Fen; Hickey, Kathleen T; Taylor, Jacquelyn Y; Gallek, Matthew J

    2013-03-01

    This article provides an update on cardiovascular genomics using three clinically relevant exemplars, including myocardial infarction (MI) and coronary artery disease (CAD), stroke, and sudden cardiac death (SCD). ORGANIZATIONAL CONSTRUCT: Recent advances in cardiovascular genomic research, testing, and clinical implications are presented. Genomic nurse experts reviewed and summarized recent salient literature to provide updates on three selected cardiovascular genomic conditions. Research is ongoing to discover comprehensive genetic markers contributing to many common forms of cardiovascular disease (CVD), including MI and stroke. However, genomic technologies are increasingly being used clinically, particularly in patients with long QT syndrome (LQTS) or hypertrophic cardiomyopathy (HCM) who are at risk for SCD. Currently, there are no clinically recommended genetic tests for many common forms of CVD even though direct-to-consumer genetic tests are being marketed to healthcare providers and the general public. On the other hand, genetic testing for patients with certain single gene conditions, including channelopathies (e.g., LQTS) and cardiomyopathies (e.g., HCM), is recommended clinically. Nurses play a pivotal role in cardiogenetics and are actively engaged in direct clinical care of patients and families with a wide variety of heritable conditions. It is important for nurses to understand current development of cardiovascular genomics and be prepared to translate the new genomic knowledge into practice. © 2013 Sigma Theta Tau International.

  9. Subtracted dynamic MR perfusion source images (sMRP-SI) provide collateral blood flow assessment in MCA occlusions and predict tissue fate

    Energy Technology Data Exchange (ETDEWEB)

    Villringer, Kersten; Serrano-Sandoval, Rafael; Galinovic, Ivana; Ostwaldt, Ann-Christin; Brunecker, Peter; Fiebach, Jochen B. [Charite-Universitaetsmedizin, Academic Neuroradiology, Center for Stroke Research (CSB), Berlin (Germany); Grittner, Ulrike [Charite, Universitaetsmedizin Berlin, Center for Stroke Research, Berlin (Germany); Charite, Department for Biostatistics and Clinical Epidemiology, Berlin (Germany); Schneider, Alice [Charite, Universitaetsmedizin Berlin, Center for Stroke Research, Berlin (Germany); Rocco, Andrea [Charite, Department of Neurology and Center for Stroke Research, Berlin (Germany)

    2016-05-15

    Collateral blood flow is accepted as a predictive factor of tissue fate in ischemic stroke. Thus, we aimed to evaluate a new method derived from MR perfusion source images to assess collateral flow in patients with ICA/MCA occlusions. A total of 132 patients of the prospective 1000+ study were examined. MR perfusion source images were assessed according to Δimg{sub n} = img{sub n} + 1 - img{sub n} - 1 using the five-grade Higashida collateral flow rating system. Higashida scores were correlated to mismatch (MM) volume, mismatch ratio, day 6 FLAIR lesion volumes and day 90 mRS. Patients with Higashida scores 3 and 4 had significantly lower admission NIHSS, smaller FLAIR day 6 lesion volumes (p < 0.001) and higher rates of better long-term outcome (mRS 0-2, p = 0.002). There was a linear trend for the association of Higashida grade 1 (p = 0.002) and 2 (p = 0.001) with unfavourable outcome (day 90 mRS 3-6), but no significant association was found for MM volume, MM ratio and day 90 mRS. Inter-rater agreement was 0.58 (95 % CI 0.43-0.73) on day 1, 0.70 (95 % CI 0.58-0.81) on day 2. sMRP-SI Higashida score offers a non-invasive collateral vessel and tissue perfusion assessment of ischemic tissue. The predictive value of Higashida rating proved superior to MM with regard to day 90 mRS. (orig.)

  10. Subtracted dynamic MR perfusion source images (sMRP-SI) provide collateral blood flow assessment in MCA occlusions and predict tissue fate

    International Nuclear Information System (INIS)

    Villringer, Kersten; Serrano-Sandoval, Rafael; Galinovic, Ivana; Ostwaldt, Ann-Christin; Brunecker, Peter; Fiebach, Jochen B.; Grittner, Ulrike; Schneider, Alice; Rocco, Andrea

    2016-01-01

    Collateral blood flow is accepted as a predictive factor of tissue fate in ischemic stroke. Thus, we aimed to evaluate a new method derived from MR perfusion source images to assess collateral flow in patients with ICA/MCA occlusions. A total of 132 patients of the prospective 1000+ study were examined. MR perfusion source images were assessed according to Δimg n = img n + 1 - img n - 1 using the five-grade Higashida collateral flow rating system. Higashida scores were correlated to mismatch (MM) volume, mismatch ratio, day 6 FLAIR lesion volumes and day 90 mRS. Patients with Higashida scores 3 and 4 had significantly lower admission NIHSS, smaller FLAIR day 6 lesion volumes (p < 0.001) and higher rates of better long-term outcome (mRS 0-2, p = 0.002). There was a linear trend for the association of Higashida grade 1 (p = 0.002) and 2 (p = 0.001) with unfavourable outcome (day 90 mRS 3-6), but no significant association was found for MM volume, MM ratio and day 90 mRS. Inter-rater agreement was 0.58 (95 % CI 0.43-0.73) on day 1, 0.70 (95 % CI 0.58-0.81) on day 2. sMRP-SI Higashida score offers a non-invasive collateral vessel and tissue perfusion assessment of ischemic tissue. The predictive value of Higashida rating proved superior to MM with regard to day 90 mRS. (orig.)

  11. The regulation of subcutaneous adipose tissue blood flow in the ischaemic forefoot during 24 hours. Studies using the 133-xenon wash-out technique continuously over 24 hours

    DEFF Research Database (Denmark)

    Jelnes, R

    1988-01-01

    A method for continuous measurement of subcutaneous adipose tissue blood flow in the forefoot during 24 hours (SBF) is described. The method is based on the radioisotope wash-out principle using 133-Xenon. A portable semiconductor detector is placed just above a local depot of 1-2 microCi 133-Xenon...... indicator. Characteristic 24-hour blood flow patterns were unveiled in patients with normal peripheral circulation and in patients having ischaemic nocturnal rest pain. In normals SBF doubled from day to night. This is ascribed to the local veno-arteriolar sympathetic axon reflex, which induces arteriolar...... vasoconstriction when the transmural pressure of the veins exceeds approximately 25 mmHg. In patients having ischaemic rest pains SBF was reduced by 37% on the average from day to night. This was caused by nocturnal hypotension, which is reflected proportionally in the foot. As the resistance vessels most probably...

  12. The Diagnosis of Gastric Mucosa-associated Lymphoid Tissue Lymphoma by Flow Cytometry and Fluorescence in situ Hybridization of Biopsy Specimens.

    Science.gov (United States)

    Matsueda, Katsunori; Omote, Sizuma; Sakata, Masahiro; Fujita, Isao; Horii, Jouichiro; Toyokawa, Tatsuya

    2018-04-15

    Mucosa-associated lymphoid tissue (MALT) lymphoma and reactive inflammatory lymphoid changes are frequently difficult to distinguish based on a routine histological differential diagnosis. We were unable to diagnose gastric MALT lymphoma histologically using specimens obtained by endoscopy, although a flow cytometry (FCM) analysis demonstrated clonality of neoplastic cells by separating cells by CD45 gating. Furthermore, a fluorescence in situ hybridization (FISH) analysis showed trisomy 18. We therefore diagnosed gastric MALT lymphoma with trisomy 18. We recommend that FCM and FISH analyses of biopsy specimens be considered for diagnosing gastric MALT lymphoma if this diagnosis is suspected based on endoscopic findings.

  13. Effect of Interstitial Fluid Flow on Drug-Coated Balloon Delivery in a Patient-Specific Arterial Vessel with Heterogeneous Tissue Composition: A Simulation Study.

    Science.gov (United States)

    Sarifuddin; Mandal, Prashanta Kumar

    2018-03-05

    Angioplasty with drug-coated balloons (DCBs) using excipients as drug carriers is emerging as a potentially viable strategy demonstrating clinical efficacy and proposing additional compliance for the treatment of obstructive vascular diseases. An attempt is made to develop an improved computational model where attention has been paid to the effect of interstitial flow, that is, plasma convection and internalization of bound drug. The present model is capable of capturing the phenomena of the transport of free drug and its retention, and also the internalization of drug in the process of endocytosis to atherosclerotic vessel of heterogeneous tissue composition comprising of healthy tissue, as well as regions of fibrous cap, fibro-fatty, calcified and necrotic core lesions. Image processing based on an unsupervised clustering technique is used for color-based segmentation of a patient-specific longitudinal image of atherosclerotic vessel obtained from intravascular ultrasound derived virtual histology. As the residence time of drug in a stent-based delivery within the arterial tissue is strongly influenced by convective forces, effect of interstitial fluid flow in case of DCB delivery can not be ruled out, and has been investigated by modeling it through unsteady Navier-Stokes equations. Transport of free drug is modeled by considering unsteady advection-reaction-diffusion process, while the bound drug, assuming completely immobilized in the tissue, by unsteady reaction process. The model also takes into account the internalization of drug through the process of endocytosis which gets degraded by the lysosomes and finally recycled into the extracellular fluid. All the governing equations representing the flow of interstitial fluid, the transport of free drug, the metabolization of free drug into bound phase and the process of internalization along with the physiologically realistic boundary and initial conditions are solved numerically using marker and cell method

  14. Cyclo-oxygenase-2 mediated prostaglandin release regulates blood flow in connective tissue during mechanical loading in humans

    DEFF Research Database (Denmark)

    Langberg, H; Boushel, Robert Christopher; Skovgaard, D

    2003-01-01

    prior to the experiment) or COX unspecific (n = 8, indomethacin 100 mg (12 and 1 h pre-experiment) and acetyl salicylic acid 500 mg day-1 for 3 days pre-experiment). Prostaglandin E2 (PGE2) concentration was determined by microdialysis and blood flow by 133Xe washout. In C, interstitial PGE2 rose from...

  15. Effect of short-term scrotal hyperthermia on spermatological parameters, testicular blood flow and gonadal tissue in dogs

    NARCIS (Netherlands)

    Henning, H; Masal, C; Herr, A; Wolf, K; Urhausen, C; Beineke, A; Beyerbach, M; Kramer, S; Günzel-Apel, A-R

    The objective was to assess the effect of a short-term scrotal hyperthermia in dogs on quantitative and qualitative ejaculate parameters, testicular blood flow and testicular and epididymal histology. After a control period, the scrotum of seven normospermic adult beagle dogs was insulated with a

  16. Functional and morphological parameters with tissue characterization of cardiovascular magnetic imaging in clinically verified ''infarct-like myocarditis''

    Energy Technology Data Exchange (ETDEWEB)

    Schwab, Johannes [Paracelsus Medical Univ., General Hospital Nuremberg (Germany). Dept. of Cardiology and Radiology; Rogg, H.J.; Pauschinger, M.; Fessele, K. [Paracelsus Medical Univ., General Hospital Nuremberg (Germany). Dept. of Cardiology; Bareiter, T.; Baer, I. [Paracelsus Medical Univ., General Hospital Nuremberg (Germany). Dept. of Cardiology and Neuroradiology; Loose, R. [Paracelsus Medical Univ., General Hospital Nuremberg (Germany). Dept. of Radiology

    2016-04-15

    Cardiac magnetic resonance (CMR) has increasingly proved to be a valuable diagnostic tool for evaluating patients with suspected myocarditis. The objective of this study was to evaluate the diagnostic value of functional and morphological parameters including tissue characterization in patients with ''infarct-like myocarditis''. 43 patients with clinically verified cases of ''infarct-like myocarditis'' (median time to MRI scanning after admission for acute symptoms 3 days) and 35 control patients matched by age and sex were included in this retrospective case control study. In this study we used a 1.5 T MRI scanner conducting steady-state-free-precession sequences, T2-weighted imaging, T1-weighted imaging before and after contrast administration and late gadolinium enhancement sequences. According to the recommendations for CMR diagnosis of myocarditis (Lake Louise consensus criteria), a scan was positive for acute myocarditis if 2 of 3 CMR criteria were present. 30 % of the patients with ''infarct-like myocarditis'' had a reduced left ventricular ejection fraction, 11 % had an increased LV end-diastolic volume index and 35 % had an increased LV mass index. The sensitivity of wall motion abnormalities was 63 % with a regional distribution in 49 %. In 47 % of cases regional wall motion abnormalities were present in the lateral left ventricular segments. Pericardial effusions were discovered in 65 % of cases with a circular appearance in 21 % and focal manifestation in 44 %. The diagnostic sensitivity, specificity, and accuracy of CMR in patients with ''infarct-like myocarditis'' were 67 %, 100 % and 82 %, respectively. The LGE alone was the most sensitive test parameter with 86 %, providing a specificity of 100 % and accuracy of 92 %. Our study results can be applied to the subgroup of patients with ''infarct-like myocarditis'', where we found that LGE alone was the

  17. Tissue Doppler Imaging and Focal, Late-Onset Anthracycline-Induced Cardiovascular Disease in Long Term Survivors of Childhood Cancer: A Research Article.

    Science.gov (United States)

    Rajapreyar, Prakadeshwari; Lorenzana, Adonis; Prabhu, Anuradha; Szpunar, Susan; Anne, Premchand

    2016-08-01

    In anthracycline-induced cardiomyopathy, the onset of diastolic dysfunction occurs before systolic dysfunction. Although, conventional echocardiogram is the standard method to assess cardiac function post anthracycline therapy, Tissue Doppler Imaging (TDI) may detect early onset cardiac diastolic dysfunction among anthracycline-recipient survivors of childhood cancers. There are limited data on the use of TDI in assessing anthracycline-associated cardiotoxicity in children. To evaluate the role of Tissue Doppler Imaging (TDI) in assessing late-onset cardiotoxicity in survivors of paediatric cancers. This was a single site, observational, blinded study of 11 long-term survivors of childhood cancer who had been treated with anthracyclines and 22 age-matched controls. The study group and the control group underwent conventional echo and TDI; operators were blind to study group. Conventional echo measurements were obtained. TDI was used to assess systolic and diastolic parameters at the mid-interventricular septum and lateral and medial annuli of the mitral valve; these parameters included: systolic wave (S'), early diastolic wave (E'), late diastolic wave (A'), Isovolemic Contraction Time (ICT), Isovolemic Relaxation Time (IRT) and Ejection Time (ET). Myocardial Performance Index (MPI) was also calculated. Conventional echo measurements were similar in both groups. Using TDI, cases had a lower mean E' velocity (9.7 ± 1.7 cm/s vs. 11.4 ± 1.3 cm/s, p=0.004) and a lower E'/A' (1.8 ± 0.5 vs. 2.2 ± 0.4, p=0.022) at the mid-interventricular septum than controls. The mean E' septum velocity in chemotherapy-recipients who also received chest radiotherapy was 8.5±0.5 cm/s in comparison to 10.2±1.7 cm/s in those that did not receive chest radiotherapy but this not achieve statistical significance. We did not find any additional associations between TDI parameters and patients' gender, age of diagnosis, length of follow-up and dose of anthracycline. In long-term survivors

  18. TU-D-209-06: Head and Neck Tissue Dose From X-Ray Scatter to Physicians Performing Cardiovascular Procedures

    Energy Technology Data Exchange (ETDEWEB)

    Fetterly, K; Schueler, B; Grams, M [Mayo Clinic, Rochester, MN (United States); Sturchio, G [Mayo Clinic, Jacksonville, FL (United States)

    2016-06-15

    Purpose: The purpose of this work was to characterize the spatial distribution of scatter radiation to the head and neck of a physician performing an x-ray interventional procedure and assess brain, eye lens, and carotid artery dose. Methods: Radiographic x-ray beams were tuned to match the peak energy (56 to 106 keV) and HVL (3.5 to 6.5 mm Al) of x-ray scatter originating from a patient during a fluoroscopic procedure. The radiographic beam was directed upon a Rando phantom from an inferior-left location to mimic a typical patient-operator geometric relationship. A lead-equivalent protective garment was secured to the phantom. Direct exposure Gafchromic film (XRQA2) was placed between the transverse plane layers of the head and neck region of the phantom and exposed with 4 scatter-equivalent radiographic beams. A 3×3 cm{sup 2} film placed at the left collar of the phantom was used to monitor incident dose in the position of a radiation monitoring badge. The films were converted to 2D dose distribution maps using FilmQA Pro software and an Epson 11000-XL scanner. The 2D dose distributions maps were normalized by the left collar dose and the percent of left collar dose (%LCD) was calculated for select tissues. Results: The dose maps had high dynamic range (10{sub 4}) and spatial detail. Considering all transverse planes and 4 scatter beam qualities, the median %LCD values were: whole brain 8.5%, left brain 13%, right brain 5.4%, left eye lens 67%, right eye lens 25%, left carotid artery 72%, and right carotid artery 28%. Conclusion: Scatter radiation dose to an operator can be simulated using a tuned radiographic beam and used to expose a phantom and Gafchromic film, thereby creating detailed 2D dose distribution maps. This work facilitates individualized estimation of dose to select head and neck tissues based on an operator’s radiation monitoring badge value.

  19. Cardiovascular disease

    African Journals Online (AJOL)

    user

    risk factors. These associations involve obesity and. 37 may be modified by improving fitness . Sedentary lifestyle with its associated risk is increasing becoming rampant in Africa due to rural to urban migration. Injury to endothelium causes endothelial dysfunction. Cardiovascular disease: A Global Epidemic extending into.

  20. HIV and Cardiovascular Disease

    Science.gov (United States)

    ... 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 ...

  1. Fabrication of novel high surface area mushroom gilled fibers and their effects on human adipose derived stem cells under pulsatile fluid flow for tissue engineering applications.

    Science.gov (United States)

    Tuin, Stephen A; Pourdeyhimi, Behnam; Loboa, Elizabeth G

    2016-05-01

    The fabrication and characterization of novel high surface area hollow gilled fiber tissue engineering scaffolds via industrially relevant, scalable, repeatable, high speed, and economical nonwoven carding technology is described. Scaffolds were validated as tissue engineering scaffolds using human adipose derived stem cells (hASC) exposed to pulsatile fluid flow (PFF). The effects of fiber morphology on the proliferation and viability of hASC, as well as effects of varied magnitudes of shear stress applied via PFF on the expression of the early osteogenic gene marker runt related transcription factor 2 (RUNX2) were evaluated. Gilled fiber scaffolds led to a significant increase in proliferation of hASC after seven days in static culture, and exhibited fewer dead cells compared to pure PLA round fiber controls. Further, hASC-seeded scaffolds exposed to 3 and 6dyn/cm(2) resulted in significantly increased mRNA expression of RUNX2 after one hour of PFF in the absence of soluble osteogenic induction factors. This is the first study to describe a method for the fabrication of high surface area gilled fibers and scaffolds. The scalable manufacturing process and potential fabrication across multiple nonwoven and woven platforms makes them promising candidates for a variety of applications that require high surface area fibrous materials. We report here for the first time the successful fabrication of novel high surface area gilled fiber scaffolds for tissue engineering applications. Gilled fibers led to a significant increase in proliferation of human adipose derived stem cells after one week in culture, and a greater number of viable cells compared to round fiber controls. Further, in the absence of osteogenic induction factors, gilled fibers led to significantly increased mRNA expression of an early marker for osteogenesis after exposure to pulsatile fluid flow. This is the first study to describe gilled fiber fabrication and their potential for tissue engineering

  2. Emerging role of neurotensin in regulation of the cardiovascular system.

    Science.gov (United States)

    Osadchii, Oleg E

    2015-09-05

    There is increasing evidence in support of an important role played by neurotensin (NT), a tridecapeptide originally found in bovine hypothalamus, in regulation of cardiovascular system. Elevated systemic levels of NT may contribute to pathogenesis of acute circulatory disoders, and predict the risk for cardiovascular morbidity and mortality in population-based studies. Within cardiovascular system, NT-containing neural fibers are found in close contact with atrial and ventricular cardiac myocytes, cardiac conduction system, intracardiac ganglia, as well as coronary vessels in humans and various animal species. The density of NT-immunoreactive innervation is reduced in cardiac disease. NT produces a variety of cardiovascular actions including effects on heart rate, myocardial contractility, systemic blood pressure, coronary vascular tone, venous smooth muscle tone, and regional blood flow in gastrointestinal tract, cutaneous and adipose tissue. NT could trigger cardiovascular reflexes by stimulating primary visceral afferents synaptically connected with preganglionic sympathetic neurons at the spinal cord. Structural determinants of biological activity of NT reside primarily in the C-terminal portion of its molecule which is responsible for receptor activation. NT effects are mediated via activation of NT receptors, or produced indirectly via stimulation of release of various endogenous neuromodulators/neurotransmitters such as histamine, catecholamines and prostaglandins. Three subtypes of NT receptor (NTS1, NTS2 and NTS3) have been shown to be expressed in the myocardium. NTS1, a high-affinity NT binding site coupled to phospholipase C-inositoltrisphosphate transduction pathway, is thought to mediate NT-induced cardiovascular responses. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Non-contact radiofrequency-induced reduction of subcutaneous abdominal fat correlates with initial cardiovascular autonomic balance and fat tissue hormones: safety analysis [v1; ref status: indexed, http://f1000r.es/4pj

    Directory of Open Access Journals (Sweden)

    Jiri Pumprla

    2015-02-01

    Full Text Available Background and objective: The non-invasive reduction of subcutaneous abdominal fat became popular in the last decade. Radiofrequency (RF, non-contact, selective-field device Vanquish® has been developed to selectively induce deep fat tissue heating to reduce waist circumference. Our analysis evaluates immediate and sustained effects of this treatment on cardiovascular autonomic function and on selected metabolic parameters. Study design/patients and methods: A retrospective proof-of-concept analysis of RF treatment effects was conducted in 20 individuals with metabolic syndrome, to reduce the subcutaneous abdominal fat. Four 30-minutes treatment sessions (manufacturer´s standard protocol were performed in 1-week intervals. Vital signs, ECG, lab screening, body composition, subcutaneous fat thickness and spectral analysis of heart rate variability (HRV have been examined before, after the 1st and 4th treatment, and at follow-up visits 1 month and 3 months after the treatment. Results: The RF treatment led to a significant reduction of abdominal circumference after the 4th session (p0.59, p<0.04. Conclusions: Our analysis shows that the selective-field RF treatment is safe and efficient for reduction of subcutaneous abdominal fat. While the treatment increases the immediate sympathetic response of the body to deep tissue heating, no sustained change in autonomic function could be recorded at 1 month follow-up. The observed correlation between initial VLF spectral power and waist circumference reduction at follow-up, as well as the association of initial adiponectin values and immediate autonomic response to the treatment might be instrumental for decisions on body contouring strategies.

  4. Predicting permeability of regular tissue engineering scaffolds: scaling analysis of pore architecture, scaffold length, and fluid flow rate effects.

    Science.gov (United States)

    Rahbari, A; Montazerian, H; Davoodi, E; Homayoonfar, S

    2017-02-01

    The main aim of this research is to numerically obtain the permeability coefficient in the cylindrical scaffolds. For this purpose, a mathematical analysis was performed to derive an equation for desired porosity in terms of morphological parameters. Then, the considered cylindrical geometries were modeled and the permeability coefficient was calculated according to the velocity and pressure drop values based on the Darcy's law. In order to validate the accuracy of the present numerical solution, the obtained permeability coefficient was compared with the published experimental data. It was observed that this model can predict permeability with the utmost accuracy. Then, the effect of geometrical parameters including porosity, scaffold pore structure, unit cell size, and length of the scaffolds as well as entrance mass flow rate on the permeability of porous structures was studied. Furthermore, a parametric study with scaling laws analysis of sample length and mass flow rate effects on the permeability showed good fit to the obtained data. It can be concluded that the sensitivity of permeability is more noticeable at higher porosities. The present approach can be used to characterize and optimize the scaffold microstructure due to the necessity of cell growth and transferring considerations.

  5. Stem cells and the regeneration of the aging cardiovascular system.

    Science.gov (United States)

    Ballard, Victoria L T; Edelberg, Jay M

    2007-04-27

    It is well established that cardiovascular repair mechanisms become progressively impaired with age and that advanced age is itself a significant risk factor for cardiovascular disease. Although therapeutic developments have improved the prognosis for those with cardiovascular disease, mortality rates have nevertheless remained virtually unchanged in the last twenty years. Clearly, there is a need for alternative strategies for the treatment of cardiovascular disease. In recent years, the idea that the heart is capable of regeneration has raised the possibility that cell-based therapies may provide such an alternative to conventional treatments. Cells that have the potential to generate cardiomyocytes and vascular cells have been identified in both the adult heart and peripheral tissues, and in vivo experiments suggest that these cardiovascular stem cells and cardiovascular progenitor cells, including endothelial progenitor cells, are capable of replacing damaged myocardium and vascular tissues. Despite these findings, the endogenous actions of cardiovascular stem cells and cardiovascular progenitor cells appear to be insufficient to protect against cardiovascular disease in older individuals. Because recent evidence suggests that cardiovascular stem cells and cardiovascular progenitor cells are subject to age-associated changes that impair their function, these changes may contribute to the dysregulation of endogenous cardiovascular repair mechanisms in the aging heart and vasculature. Here we present the evidence for the impact of aging on cardiovascular stem cell/cardiovascular progenitor cell function and its potential importance in the increased severity of cardiovascular pathophysiology observed in the geriatric population.

  6. Differential diagnosis and diagnostic flow chart of joint hypermobility syndrome/ehlers-danlos syndrome hypermobility type compared to other heritable connective tissue disorders.

    Science.gov (United States)

    Colombi, Marina; Dordoni, Chiara; Chiarelli, Nicola; Ritelli, Marco

    2015-03-01

    Joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type (JHS/EDS-HT) is an evolving and protean disorder mostly recognized by generalized joint hypermobility and without a defined molecular basis. JHS/EDS-HT also presents with other connective tissue features affecting a variety of structures and organs, such as skin, eye, bone, and internal organs. However, most of these signs are present in variable combinations and severity in many other heritable connective tissue disorders. Accordingly, JHS/EDS-HT is an "exclusion" diagnosis which needs the absence of any consistent feature indicative of other partially overlapping connective tissue disorders. While both Villefranche and Brighton criteria include such an exclusion as a mandatory item, a systematic approach for reaching a stringent clinical diagnosis of JHS/EDS-HT is still lacking. The absence of a consensus on the diagnostic approach to JHS/EDS-HT concerning its clinical boundaries with similar conditions contribute to limit our actual understanding of the pathologic and molecular bases of this disorder. In this review, we revise the differential diagnosis of JHS/EDS-HT with those heritable connective tissue disorders which show a significant overlap with the former and mostly include EDS classic, vascular and kyphoscoliotic types, osteogenesis imperfecta, Marfan syndrome, Loeys-Dietz syndrome, arterial tortuosity syndrome, and lateral meningocele syndrome. A diagnostic flow chart is also offered with the attempt to support the less experienced clinician in stringently recognizing JHS/EDS-HT and stimulate the debate in the scientific community for both management and research purposes. © 2015 Wiley Periodicals, Inc.

  7. Cardiovascular system

    International Nuclear Information System (INIS)

    Soulen, R.L.; Grosh, J.

    1984-01-01

    Invasive cardiovascular diagnostic procedures involve a finite risk and therefore can be recommended only when the benefit appears to exceed the risk by a substantial margin. The risk/benefit ratio varies not only with the procedure concerned but with the status of the vascular system, concomitant diseases, and the risks of both the suspected illness and its treatment. The risks inherent in the procedures per se are detailed in the sections to follow

  8. A comprehensive guide to telocytes and their great potential in cardiovascular system.

    Science.gov (United States)

    Kucybala, I; Janas, P; Ciuk, S; Cholopiak, W; Klimek-Piotrowska, W; Holda, M K

    2017-01-01

    Telocytes, a recently discovered type of interstitial cells, have a very distinctive morphology - the small cell body with long extensions, named telopodes. In our review, apart from introducing general aspects of telocytes, we focus on properties, functions and future potential of those cells in cardiovascular system. However, physiological functions of telocytes in cardiovascular system are still regarded as quite enigmatic. Previous studies claim that they play a role in organogenesis and regeneration, bioelectrical signalling, mechanoelectrical coupling, anti-oxidative protection, angiogenesis and regulation of blood flow. As well, they are presumably connected with the presence of blood-myocardium barrier and proper organisation of extracellular matrix. Moreover, there exists a significant link between the quantity of telocytes in tissue and numerous cardiovascular diseases such as: myocardial infarction, cardiomyopathies, systemic sclerosis, heart failure, atrial fibrillation, isolated atrial amyloidosis, myxomatous valve degeneration and hyperplastic consequences of vascular injury. Thanks to their unique properties, telocytes might be a breakthrough in treatment of cardiovascular diseases, as they may be effective in reversing effects of myocardial infarction. Telocytes also may play a major role in tissue engineering - they might be the key factor in creating stable and efficient vascular network in larger synthetic tissues or organs (Tab. 1, Fig. 3, Ref. 53).

  9. Cardiovascular Physiology of Dinosaurs.

    Science.gov (United States)

    Seymour, Roger S

    2016-11-01

    Cardiovascular function in dinosaurs can be inferred from fossil evidence with knowledge of how metabolic rate, blood flow rate, blood pressure, and heart size are related to body size in living animals. Skeletal stature and nutrient foramen size in fossil femora provide direct evidence of a high arterial blood pressure, a large four-chambered heart, a high aerobic metabolic rate, and intense locomotion. But was the heart of a huge, long-necked sauropod dinosaur able to pump blood up 9 m to its head? ©2016 Int. Union Physiol. Sci./Am. Physiol. Soc.

  10. Simultaneous measurement of local cortical blood flow and tissue oxygen saturation by Near infra-red Laser Doppler flowmetry and remission spectroscopy in the pig brain.

    Science.gov (United States)

    Walter, B; Bauer, R; Krug, A; Derfuss, Th; Traichel, F; Sommer, N

    2002-01-01

    In the current study we evaluated the combined use of Near-infrared Laser-Doppler flowmetry (NiLDF) and Remission Spectroscopy (RS) for measurement of regional perfusion and oxygen saturation of the cerebral cortex. An epidural probe for combined measurements of NiLDF and RS was placed above the parietal or frontal cortex of nine anesthetized juvenile pigs. Cerebral perfusion pressure (CPP) was stepwise decreased by intracisternal infusion of artificial CSF at clamped arterial blood pressure (baseline, CPP50, CPP40, CPP30 mmHg, ischemia). Subsequent reperfusion was followed for 3 h. Regional cerebral blood flow (rCBF) was measured with colored microspheres (CMS) and compared with corresponding NiLDF values during CMS injection. Cerebral venous oxygen saturation was measured in blood samples withdrawn from the sagittal sinus and compared with simultaneous recordings of tissue oxygenation during blood withdrawal. Linear regression analysis resulted in a significant correlation (p measured with CMS and NiLDF (r = 0.92, n = 39). A significant correlation was also found for tissue oxygen saturation--as measured with RS--and cerebral venous oxygen saturation (r = 0.85, n = 67). Although the problem of spatial variability remains to be solved, the combined use of NiLDF and RS allows continuous and non-invasive monitoring of changes of key parameters of oxygen metabolism within the cerebral cortex.

  11. Lymphatic flow in humans as indicated by the clearance of 125I-labeled albumin from the subcutaneous tissue of the leg

    International Nuclear Information System (INIS)

    Fernandez, M.J.; Davies, W.T.; Owen, G.M.; Tyler, A.

    1983-01-01

    Since the removal of albumin from the extracellular space and its return to the vascular compartment is the essential function of the lymphatic system, the rate at which it is removed from the interstitial tissue may be regarded as a means of estimating lymphatic efficiency. An objective measure of lymphatic function can be obtained by monitoring the rate of clearance following injection of 125 I-labeled albumin (RIHSA) from the subcutaneous tissue of a limb. The clearance of 125 I-RIHSA from lower limb was monitored in a group of patients with normal limbs, patients with unilateral edema due to deep vein thrombosis, and patients with bilateral edema due to hypoproteinemia. The mean T1/2 in normal legs was 32.7 hr, compared to 23.7 hr in edematous limbs due to deep vein thrombosis and 19.4 in edematous limbs due to hypoproteinemia. There is a clear-cut difference in clearance rate between edematous and nonedematous limbs. This suggests that lymphatic flow is increased in edema due to venous obstruction and hypoproteinemia

  12. Application of acoustic microscopy to assessment of cardiovascular biomechanics

    Science.gov (United States)

    Saijo, Yoshifumi; Sasaki, Hidehiko; Nitta, Shin-ichi; Tanaka, Motonao; Joergensen, Claus S.; Falk, Erling

    2002-11-01

    Acoustic microscopy provides information on physical and mechanical properties of biological tissues, while optical microscopy with various staining techniques provides chemical properties. The biomechanics of tissues is especially important in cardiovascular system because its pathophysiology is closely related with mechanical stresses such as blood pressure or blood flow. A scanning acoustic microscope (SAM) system with tone-burst ultrasound in the frequency range of 100-200 MHz has been developed, and attenuation and sound speed of tissues have been measured. In human coronary arteries, attenuation and sound speed were high in calcification and collagen, while both values were low in smooth muscle and lipid. Another SAM system with 800-MHz-1.3-GHz ultrasound was applied for aortas of Apo-E deficient mouse, which is known to develop atherosclerosis. Attenuation of ultrasound was significantly higher in type 1 collagen compared to type 3 collagen. Recently, a new type FFT-SAM using a single-pulse, broadband frequency range ultrasound (20-150 MHz) has been developed. Cardiac allograft was observed by FFT-SAM and the acoustic properties were able to grade allograft rejection. SAM provides very useful information for assessing cardiovascular biomechanics and for understanding normal and abnormal images of clinical ultrasound.

  13. Cardiotoxicodynamics: Toxicity of Cardiovascular Xenobiotics.

    Science.gov (United States)

    Menke, Nathan B; Walsh, Steven J; King, Andrew M

    2015-08-01

    Maintaining adequate tissue perfusion depends on a variety of factors, all of which can be influenced by xenobiotics (substances foreign to the body, including pharmaceuticals, chemicals, and natural compounds). Volume status, systemic vascular resistance, myocardial contractility, and cardiac rhythm all play a significant role in ensuring hemodynamic stability and proper cardiovascular function. Direct effects on the nervous system, the vasculature, or the heart itself as well as indirect metabolic effects may play a significant role in the development of cardiotoxicity. This article is dedicated to discussion of the disruption of cardiovascular physiology by xenobiotics. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Interventional Cardiovascular Magnetic Resonance Imaging

    Science.gov (United States)

    Saikus, Christina E.; Lederman, Robert J.

    2010-01-01

    Cardiovascular magnetic resonance (CMR) combines excellent soft-tissue contrast, multiplanar views, and dynamic imaging of cardiac function without ionizing radiation exposure. Interventional cardiovascular magnetic resonance (iCMR) leverages these features to enhance conventional interventional procedures or to enable novel ones. Although still awaiting clinical deployment, this young field has tremendous potential. We survey promising clinical applications for iCMR. Next, we discuss the technologies that allow CMR-guided interventions and, finally, what still needs to be done to bring them to the clinic. PMID:19909937

  15. Biology and Mechanics of Blood Flows Part I: Biology

    CERN Document Server

    Thiriet, Marc

    2008-01-01

    Biology and Mechanics of Blood Flows presents the basic knowledge and state-of-the-art techniques necessary to carry out investigations of the cardiovascular system using modeling and simulation. Part I of this two-volume sequence, Biology, addresses the nanoscopic and microscopic scales. The nanoscale corresponds to the scale of biochemical reaction cascades involved in cell adaptation to mechanical stresses among other stimuli. The microscale is the scale of stress-induced tissue remodeling associated with acute or chronic loadings. The cardiovascular system, like any physiological system, has a complicated three-dimensional structure and composition. Its time dependent behavior is regulated, and this complex system has many components. In this authoritative work, the author provides a survey of relevant cell components and processes, with detailed coverage of the electrical and mechanical behaviors of vascular cells, tissues, and organs. Because the behaviors of vascular cells and tissues are tightly coupl...

  16. Vortex flow during early and late left ventricular filling in normal subjects : Quantitative characterization using retrospectively-gated 4D flow cardiovascular magnetic resonance and three-dimensional vortex core analysis

    NARCIS (Netherlands)

    Elbaz, M.S.M.; Calkoen, E.E.; Westenberg, J.J.M.; Lelieveldt, B.P.F.; Roest, A.A.W.; Van der Geest, R.J.

    2014-01-01

    Background LV diastolic vortex formation has been suggested to critically contribute to efficient blood pumping function, while altered vortex formation has been associated with LV pathologies. Therefore, quantitative characterization of vortex flow might provide a novel objective tool for

  17. Technical Advances for the Clinical Genomic Evaluation of Sudden Cardiac Death: Verification of Next-Generation Sequencing Panels for Hereditary Cardiovascular Conditions Using Formalin-Fixed Paraffin-Embedded Tissues and Dried Blood Spots.

    Science.gov (United States)

    Baudhuin, Linnea M; Leduc, Charles; Train, Laura J; Avula, Rajeswari; Kluge, Michelle L; Kotzer, Katrina E; Lin, Peter T; Ackerman, Michael J; Maleszewski, Joseph J

    2017-12-01

    Postmortem genetic testing for heritable cardiovascular (CV) disorders is often lacking because ideal specimens (ie, whole blood) are not retained routinely at autopsy. Formalin-fixed paraffin-embedded tissue (FFPET) is ubiquitously collected at autopsy, but DNA quality hampers its use with traditional sequencing methods. Targeted next-generation sequencing may offer the ability to circumvent such limitations, but a method has not been previously described. The primary aim of this study was to develop and evaluate the use of FFPET for heritable CV disorders via next-generation sequencing. Nineteen FFPET (heart) and blood (whole blood or dried blood spot) specimens underwent targeted next-generation sequencing using a custom panel of 101 CV-associated genes. Nucleic acid yield and quality metrics were evaluated in relation to FFPET specimen age (6 months to 15 years; n=14) and specimen type (FFPET versus whole blood and dried blood spot; n=12). Four FFPET cases with a clinical phenotype of heritable CV disorder were analyzed. Accuracy and precision were 100% concordant between all sample types, with read depths >100× for most regions tested. Lower read depth, as low as 40×, was occasionally observed with FFPET and dried blood spot. High-quality DNA was obtained from FFPET samples as old as 15 years. Genomic analysis of FFPET from the 4 phenotype-positive/genotype unknown cases all revealed putative disease-causing variants. Similar performance characteristics were observed for next-generation sequencing of FFPET, whole blood, and dried blood spot in the evaluation of inherited CV disorders. Although blood is preferable for genetic analyses, this study offers an alternative when only FFPET is available. © 2017 American Heart Association, Inc.

  18. Ultrasensitive automated RNA in situ hybridization for kappa and lambda light chain mRNA detects B-cell clonality in tissue biopsies with performance comparable or superior to flow cytometry.

    Science.gov (United States)

    Guo, Ling; Wang, Zhen; Anderson, Courtney M; Doolittle, Emerald; Kernag, Siobhan; Cotta, Claudiu V; Ondrejka, Sarah L; Ma, Xiao-Jun; Cook, James R

    2018-03-01

    The assessment of B-cell clonality is a critical component of the evaluation of suspected lymphoproliferative disorders, but analysis from formalin-fixed, paraffin-embedded tissues can be challenging if fresh tissue is not available for flow cytometry. Immunohistochemical and conventional bright field in situ hybridization stains for kappa and lambda are effective for evaluation of plasma cells but are often insufficiently sensitive to detect the much lower abundance of light chains present in B-cells. We describe an ultrasensitive RNA in situ hybridization assay that has been adapted for use on an automated immunohistochemistry platform and compare results with flow cytometry in 203 consecutive tissues and 104 consecutive bone marrows. Overall, in 203 tissue biopsies, RNA in situ hybridization identified light chain-restricted B-cells in 85 (42%) vs 58 (29%) by flow cytometry. Within 83 B-cell non-Hodgkin lymphomas, RNA in situ hybridization identified restricted B-cells in 74 (89%) vs 56 (67%) by flow cytometry. B-cell clonality could be evaluated in only 23/104 (22%) bone marrow cases owing to poor RNA preservation, but evaluable cases showed 91% concordance with flow cytometry. RNA in situ hybridization allowed for recognition of biclonal/composite lymphomas not identified by flow cytometry and highlighted unexpected findings, such as coexpression of kappa and lambda RNA in 2 cases and the presence of lambda light chain RNA in a T lymphoblastic lymphoma. Automated RNA in situ hybridization showed excellent interobserver reproducibility for manual evaluation (average K=0.92), and an automated image analysis system showed high concordance (97%) with manual evaluation. Automated RNA in situ hybridization staining, which can be adopted on commonly utilized immunohistochemistry instruments, allows for the interpretation of clonality in the context of the morphological features in formalin-fixed, paraffin-embedded tissues with a clinical sensitivity similar or

  19. World Health Organization cardiovascular risk stratification and target organ damage.

    Science.gov (United States)

    Piskorz, D; Bongarzoni, L; Citta, L; Citta, N; Citta, P; Keller, L; Mata, L; Tommasi, A

    2016-01-01

    Prediction charts allow treatment to be targeted according to simple markers of cardiovascular risk; many algorithms do not recommend screening asymptomatic target organ damage which could change dramatically the assessment. To demonstrate that target organ damage is present in low cardiovascular risk hypertensive patients and it is more frequent and severe as global cardiovascular risk increases. Consecutive hypertensive patients treated at a single Latin American center. Cardiovascular risk stratified according to 2013 WHO/ISH risk prediction chart America B. Left ventricular mass assessed by Devereux method, left ventricular hypertrophy considered >95g/m(2) in women and >115g/m(2) in men. Transmitral diastolic peak early flow velocity to average septal/lateral peak early diastolic relaxation velocity (E/e' ratio) measured cut off value >13. Systolic function assessed by tissue Doppler average interventricular septum/lateral wall mitral annulus rate systolic excursion (s wave). A total of 292 patients were included of whom 159 patients (54.5%) had cardiovascular risk of 20%. Left ventricular hypertrophy was detected in 17.6% low risk patients, 27.8% in medium risk and 23.3% in high risk (p<0.05), abnormal E/e' ratio was found in 13.8%, 31.1% and 27.9%, respectively (p<0.05). Mean s wave was 8.03+8, 8.1+9 and 8.7+1cm/s for low, intermediate and high risk patients, respectively (p<0.025). Target organ damage is more frequent and severe in high risk; one over four subjects was misclassified due to the presence of asymptomatic target organ damage. Copyright © 2015 SEHLELHA. Published by Elsevier España, S.L.U. All rights reserved.

  20. Cardiovascular group

    Science.gov (United States)

    Blomqvist, Gunnar

    1989-01-01

    As a starting point, the group defined a primary goal of maintaining in flight a level of systemic oxygen transport capacity comparable to each individual's preflight upright baseline. The goal of maintaining capacity at preflight levels would seem to be a reasonable objective for several different reasons, including the maintenance of good health in general and the preservation of sufficient cardiovascular reserve capacity to meet operational demands. It is also important not to introduce confounding variables in whatever other physiological studies are being performed. A change in the level of fitness is likely to be a significant confounding variable in the study of many organ systems. The principal component of the in-flight cardiovascular exercise program should be large-muscle activity such as treadmill exercise. It is desirable that at least one session per week be monitored to assure maintenance of proper functional levels and to provide guidance for any adjustments of the exercise prescription. Appropriate measurements include evaluation of the heart-rate/workload or the heart-rate/oxygen-uptake relationship. Respiratory gas analysis is helpful by providing better opportunities to document relative workload levels from analysis of the interrelationships among VO2, VCO2, and ventilation. The committee felt that there is no clear evidence that any particular in-flight exercise regimen is protective against orthostatic hypotension during the early readaptation phase. Some group members suggested that maintenance of the lower body muscle mass and muscle tone may be helpful. There is also evidence that late in-flight interventions to reexpand blood volume to preflight levels are helpful in preventing or minimizing postflight orthostatic hypotension.

  1. Cardiovascular KATPchannels and advanced aging.

    Science.gov (United States)

    Yang, Hua-Qian; Subbotina, Ekaterina; Ramasamy, Ravichandran; Coetzee, William A

    2016-01-01

    With advanced aging, there is a decline in innate cardiovascular function. This decline is not general in nature. Instead, specific changes occur that impact the basic cardiovascular function, which include alterations in biochemical pathways and ion channel function. This review focuses on a particular ion channel that couple the latter two processes, namely the K ATP channel, which opening is promoted by alterations in intracellular energy metabolism. We show that the intrinsic properties of the K ATP channel changes with advanced aging and argue that the channel can be further modulated by biochemical changes. The importance is widespread, given the ubiquitous nature of the K ATP channel in the cardiovascular system where it can regulate processes as diverse as cardiac function, blood flow and protection mechanisms against superimposed stress, such as cardiac ischemia. We highlight questions that remain to be answered before the K ATP channel can be considered as a viable target for therapeutic intervention.

  2. Monte Carlo estimation of scatter effects on quantitative myocardial blood flow and perfusable tissue fraction using 3D-PET and 15O-water

    Science.gov (United States)

    Hirano, Yoshiyuki; Koshino, Kazuhiro; Watabe, Hiroshi; Fukushima, Kazuhito; Iida, Hidehiro

    2012-11-01

    In clinical cardiac positron emission tomography using 15O-water, significant tracer accumulation is observed not only in the heart but also in the liver and lung, which are partially outside the field-of-view. In this work, we investigated the effects of scatter on quantitative myocardium blood flow (MBF) and perfusable tissue fraction (PTF) by a precise Monte Carlo simulation (Geant4) and a numerical human model. We assigned activities to the heart, liver, and lung of the human model with varying ratios of organ activities according to an experimental time activity curve and created dynamic sinograms. The sinogram data were reconstructed by filtered backprojection. By comparing a scatter-corrected image (SC) with a true image (TRUE), we evaluated the accuracy of the scatter correction. TRUE was reconstructed using a scatter-eliminated sinogram, which can be obtained only in simulations. A scatter-uncorrected image (W/O SC) and an attenuation-uncorrected image (W/O AC) were also constructed. Finally, we calculated MBF and PTF with a single tissue-compartment model for four types of images. As a result, scatter was corrected accurately, and MBFs derived from all types of images were consistent with the MBF obtained from TRUE. Meanwhile, the PTF of only the SC was in agreement with the PTF of TRUE. From the simulation results, we concluded that quantitative MBF is less affected by scatter and absorption in 3D-PET using 15O-water. However, scatter correction is essential for accurate PTF.

  3. Cardiovascular effects of intravenous ghrelin infusion in healthy young men

    DEFF Research Database (Denmark)

    Vestergaard, Esben Thyssen; Andersen, Niels Holmark; Hansen, Troels Krarup

    2007-01-01

    Ghrelin infusion improves cardiac function in patients suffering from cardiac failure, and bolus administration of ghrelin increases cardiac output in healthy subjects. The cardiovascular effects of more continuous intravenous ghrelin exposure remain to be studied. We therefore studied the cardio......Ghrelin infusion improves cardiac function in patients suffering from cardiac failure, and bolus administration of ghrelin increases cardiac output in healthy subjects. The cardiovascular effects of more continuous intravenous ghrelin exposure remain to be studied. We therefore studied...... the cardiovascular effects of a constant infusion of human ghrelin at a rate of 5 pmol/kg per minute for 180 min. Fifteen healthy, young (aged 23.2 ± 0.5 yr), normal-weight (23.0 ± 0.4 kg/m2) men volunteered in a randomized double-blind, placebo-controlled crossover study. With the subjects remaining fasting, peak...... myocardial systolic velocity S′, tissue tracking TT, left ventricular ejection fraction EF, and endothelium-dependent flow-mediated vasodilatation were measured. Ghrelin infusion increased S′ 9% (P = 0.002) and TT 10% (P

  4. A method for matching the refractive index and kinematic viscosity of a blood analog for flow visualization in hydraulic cardiovascular models.

    Science.gov (United States)

    Nguyen, T T; Biadillah, Y; Mongrain, R; Brunette, J; Tardif, J C; Bertrand, O F

    2004-08-01

    In this work, we propose a simple method to simultaneously match the refractive index and kinematic viscosity of a circulating blood analog in hydraulic models for optical flow measurement techniques (PIV, PMFV, LDA, and LIF). The method is based on the determination of the volumetric proportions and temperature at which two transparent miscible liquids should be mixed to reproduce the targeted fluid characteristics. The temperature dependence models are a linear relation for the refractive index and an Arrhenius relation for the dynamic viscosity of each liquid. Then the dynamic viscosity of the mixture is represented with a Grunberg-Nissan model of type 1. Experimental tests for acrylic and blood viscosity were found to be in very good agreement with the targeted values (measured refractive index of 1.486 and kinematic viscosity of 3.454 milli-m2/s with targeted values of 1.47 and 3.300 milli-m2/s).

  5. Bioactive-Chylomicrons for Oral Lymphatic Targeting of Berberine Chloride: Novel Flow-Blockage Assay in Tissue-Based and Caco-2 Cell Line Models.

    Science.gov (United States)

    Elsheikh, Manal A; Elnaggar, Yosra S R; Otify, Dina Y; Abdallah, Ossama Y

    2018-01-05

    To develop novel bioactive-chylomicrons to solve oral delivery obstacles of Berberine chloride and target the lymphatic system. Berberine-loaded bioactive-chylomicrons were prepared and underwent full in vitro characterization. Intestinal permeability was appraised via both non-everted gut sac model and Caco-2 cell model. Furthermore, Bioactive-chylomicrons' cellular uptake and distribution were examined by laser scanning confocal microscopy. Finally, a novel chylomicron flow-blockage assay on tissue and cellular levels were elaborated to assess the lymphatic targeting ability. Berberine-loaded chylomicrons showed spherical vesicles of size (175.6 nm), PDI (0.229), zeta potential (-16 .6 mV) and entrapment efficiency (95.5%). Ex-vivo intestinal permeability studies demonstrated 10.5 fold enhancement in permeability of Berberine-loaded chylomicrons over free Berberine. Moreover, Caco-2 studies revealed significant improvement in chylomicrons' permeability and cellular uptake. Furthermore, confocal microscopy analyses revealed 2 fold increase in berberine-loaded chylomicrons' intracellular fluorescence. Lymphatic targeting models were successfully elaborated using cycloheximide protein synthesis inhibitor. Such models demonstrated 47 and 27.5% reduction in ex-vivo and Caco-2 permeability respectively. Finally, a good rank order correlation was established between different permeability assessment techniques. The findings shed the light on the underlying mechanisms of Berberine bioavailability improvement. Consequently, berberine-loaded chylomicrons could be considered as promising bioactive-nanocarriers for Berberine lymphatic targeting and bioavailability improvement.

  6. Correlation between the tissue Doppler, strain rate, strain imaging during the dobutamine infusion and coronary fractional flow reserve during catheterization: a comparative study.

    Science.gov (United States)

    Dagdelen, Sinan; Yuce, Murat; Emiroglu, Yunus; Ergelen, Mehmet; Pala, Selcuk; Tanalp, Ali Cevat; Izgi, Akin; Kirma, Cevat

    2005-06-22

    Coronary fractional flow reserve (FFR) as an invasive, and dobutamine stress echocardiography (DSE) as a noninvasive technique were used to detect critical coronary stenosis. This study was undertaken to assess correlation between these two techniques by using tissue Doppler, strain rate (SR), and strain imaging (S). In 17 patients (aged 54.9+/-12.6, 4 F), a total of 22 vessels were studied. On dobutamine stress echocardiography, baseline and peak systolic (Sm), early (Em) and late (Am) diastolic myocardial velocities, SR and S were recorded from parasternal view (mid-posterior segment) for radial and apical view (mid-septum) for longitudinal deformation. Then coronary FFR was performed by using intracoronary adenosine infusion, and the value of system were analyzed for longitudinal SR and S values, it had a mild correlation with SR (r = 0.47, p = 0.044) and a good correlation with S (r = 0.66, p = 0.002). The quantification of regional myocardial deformation by using DSE rather than the motion would be more appropriate in detecting the ischemic dysfunctional segment supplied by the critical coronary stenosis. Strain measurement during the dobutamine infusion may provide an information on the FFR results of the culprit vessel.

  7. Relationship between Inflammation and Cardiovascular Diseases

    OpenAIRE

    Riddhi Patel; Henish Patel; Rachana Sarawade

    2013-01-01

    Inflammation is a part of complex biological response of vascular tissue to harmful stimuli such as pathogens, damaged cells or irritants. Recent advance in basic science have established a fundamental role for inflammation immediating all stages of cardiovascular diseases from initiation, progression and complications. Inflammation is thread linking to cardiovascular diseases. Clinical studies have shown that this emerging biology of inflammation play important role in pathogenesis of acute ...

  8. Biocompatibilidade de materiais empregados na confecção de próteses cardiovasculares: comparação entre pericárdio bovino e Dacron(R The biocompatibility of cardiovascular graft materials: a comparison between bovine pericardial tissue and Dacron(R

    Directory of Open Access Journals (Sweden)

    Terezinha de J. A. Pinto

    1993-06-01

    Full Text Available Durante os últimos 25 anos, numerosos estudos têm sido efetuados visando a biocompatibilidade de materiais de uso médico-hospitalar. Isto se deve ao desenvolvimento de materiais destinados às próteses particularmente na área cardiovascular, o que motivou pesquisas relativas à problemática da compatibilidade entre superfícies biológicas ou sintéticas e o sangue. O presente trabalho objetivou comparar a avaliação da biocompatibilidade do pericárdio bovino, um dos materiais mais empregados na fabricação de válvulas cardíacas protéticas, após tratamento com glutaraldeído e formaldeído, com o material sintético conhecido como "tricot" de Dacron(R. Tanto fragmentos de pericárdio submetidos a diferentes tratamentos, como os de Dacron(R foram implantados subcutaneamente na região abdominal de ratos Wistar, por períodos de 1 a 3 meses. O exame de cortes histológicos obtidos por métodos convencionais evidenciou ausência de biocompatibilidade principalmente para o pericárdio tratado com formaldeído. Para o Dacron(R, foi constatado, comparativamente, uma perfeita biocompatibilidade. A cultura de células in vitro, com o uso de linhagens RC-IAL e Hela pelo método de revestimento com ágar, foi empregada exclusivamente para o material de origem biológica e evidenciou um grau intenso de toxicidade associado ao resíduo do agente de tratamento. Concluiu-se que existe a necessidade do aperfeiçoamento da técnica de lavagem da prótese biológica antes da implantação.During the past 25 years, numerous studies relating to medical device biocompatibility have appedared world-wide. Development of biomaterials for grafting cardiovascular applications has contributed to an increase in knowledge of the compatibility between synthetic or biological surfaces and blood. The biocompatibility of one of the materials most commonly used in the fabrication of xenograft heart valves, bovine pericardium, treated with glutaraldehyde and

  9. Regulation of the Cardiovascular System by Histamine.

    Science.gov (United States)

    Hattori, Yuichi; Hattori, Kohshi; Matsuda, Naoyuki

    2017-01-01

    Histamine mediates a wide range of cellular responses, including allergic and inflammatory reactions, gastric acid secretion, and neurotransmission in the central nervous system. Histamine also exerts a series of actions upon the cardiovascular system but may not normally play a significant role in regulating cardiovascular function. During tissue injury, inflammation, and allergic responses, mast cells (or non-mast cells) within the tissues can release large amounts of histamine that leads to noticeable cardiovascular effects. Owing to intensive research during several decades, the distribution, function, and pathophysiological role of cardiovascular H 1 - and H 2 -receptors has become recognized adequately. Besides the recognized H 1 - and H 2 -receptor-mediated cardiovascular responses, novel roles of H 3 - and H 4 -receptors in cardiovascular physiology and pathophysiology have been identified over the last decade. In this review, we describe recent advances in our understanding of cardiovascular function and dysfunction mediated by histamine receptors, including H 3 - and H 4 -receptors, their potential mechanisms of action, and their pathological significance.

  10. The impact of obesity on the parameters of cardiovascular remodeling, cerebral blood flow and autonomic regulation of cardiac rhythm in hypertensive patients

    Directory of Open Access Journals (Sweden)

    V. V. Syvolap

    2017-04-01

    hypercapnia by 23.1% (p = 0.002. Hypertensive patients with obesity and with normal body weight did not differ by temporal and spectral parameters of HRV. Index LF/HF in both groups exceeded 2 cu. Conclusions. The presence of obesity in patients with essential hypertension is accompanied by significantly higher average SBP and DBP, daily hypertension time index according to 24h ABPM, a significant increase in diastolic LA size, IVSTd, LVMI and decrease of LV volume-mass index, decreased blood flow in CCA, right ICA, left MCA, both VA and BA, index of vascular reactivity sensitive to hypercapnia in the left MCA and BA. In patients with essential hypertension regardless of whether obese or of normal body weight sympathetic part of the autonomic nervous system prevails.

  11. Laser therapy in cardiovascular disease

    Science.gov (United States)

    Rindge, David

    2009-02-01

    Cardiovascular disease is the number one cause of death worldwide. It is broadly defined to include anything which adversely affects the heart or blood vessels. One-third of Americans have one or more forms of it. By one estimate, average human life expectancy would increase by seven years if it were eliminated. The mainstream medical model seeks mostly to "manage" cardiovascular disease with pharmaceuticals or to surgically bypass or reopen blocked vessels via angioplasty. These methods have proven highly useful and saved countless lives. Yet drug therapy may be costly and ongoing, and it carries the risk of side effects while often doing little or nothing to improve underlying health concerns. Similarly, angioplasty or surgery are invasive methods which entail risk. Laser therapy1 regenerates tissue, stimulates biological function, reduces inflammation and alleviates pain. Its efficacy and safety have been increasingly well documented in cardiovascular disease of many kinds. In this article we will explore the effects of laser therapy in angina, atherosclerosis, coronary artery disease, hypertension, hyperlipidemia, myocardial infarction, stroke and other conditions. The clinical application of various methods of laser therapy, including laserpuncture and transcutaneous, supravascular and intravenous irradiation of blood will be discussed. Implementing laser therapy in the treatment of cardiovascular disease offers the possibility of increasing the health and wellbeing of patients while reducing the costs and enhancing safety of medical care.

  12. Quantitative characterization of myocardial infarction by cardiovascular magnetic resonance predicts future cardiovascular events in patients with ischemic cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Pauly John M

    2008-04-01

    Full Text Available Abstract Background Cardiovascular magnetic resonance (CMR can provide quantitative data of the myocardial tissue utilizing high spatial and temporal resolution along with exquisite tissue contrast. Previous studies have correlated myocardial scar tissue with the occurrence of ventricular arrhythmia. This study was conducted to evaluate whether characterization of myocardial infarction by CMR can predict cardiovascular events in patients with ischemic cardiomyopathy (ICM. Results We consecutively studied 86 patients with ICM (LVEF Conclusion Quantification of the scar volume and scar percentage by CMR is superior to LVEDV, LVESV, and LVEF in prognosticating the future likelihood of the development of cardiovascular events in patients with ICM.

  13. Cardiovascular lymphoscintigraphy

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-08-01

    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.

  14. Cardiovascular lymphoscintigraphy

    International Nuclear Information System (INIS)

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

    1983-01-01

    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

  15. Cardiovascular imaging

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Nuclear cardiology has grown exponentially over the past decade. The introduction of the gamma camera, the development of new radionuclides, and the implementation of computers have transformed the field of nuclear cardiology from largely research in the 1970s to routine clinical applications in the 1980s. At first, noninvasive nuclear imaging techniques were used predominantly to aid disease detection. In the ensuing years, emphasis has shifted to the functional assessment of patients with known disease. Widely available noninvasive techniques now allow the quantitative assessment of left and right ventricular function, one of the most important predictors of survival in patients with cardiac disease. Exercise radionuclide ventriculography provides valuable information on the myocardial reserve in patients with normal resting function. The serial measurement of the ventricular ejection fraction assists in the timing of valvular replacement therapy. In patients receiving doxorubicin, serial ejection fraction follow-up helps prevent the development of irreversible, drug-induced cardiomyopathy. It is now generally acknowledged that the detection of latent coronary disease is improved by the addition of 201 T1 imaging to the standard exercise electrocardiogram. Thallium imaging and infarct avid imaging with /sup 99m/Tc-pyrophosphate have proven useful in quantifying myocardial infarction size, and in assessing the value of therapy aimed at limiting infarction extent. In the evaluation of coronary artery disease, scintigraphy provides physiologic data that complements angiography, which is more anatomic. An angiographic lesion, read as a 70 percent narrowing, may not necessarily be flow-limiting, whereas one read as 40 percent, may, in fact, have physiologic consequences, if it is of sufficient length or eccentricity, or is in series with another insignificant stenosis

  16. Cardiovascular manifestations of phaeochromocytoma

    NARCIS (Netherlands)

    Prejbisz, A.; Lenders, J.W.M.; Eisenhofer, G.; Januszewicz, A.

    2011-01-01

    Clinical expression of phaeochromocytoma may involve numerous cardiovascular manifestations, but usually presents as sustained or paroxysmal hypertension associated with other signs and symptoms of catecholamine excess. Most of the life-threatening cardiovascular manifestations of phaeochromocytoma,

  17. Understanding cardiovascular disease

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000759.htm Understanding cardiovascular disease To use the sharing features on this page, ... lead to heart attack or stroke. Types of Cardiovascular Disease Coronary heart disease (CHD) is the most common ...

  18. Cardiovascular Disease and Diabetes

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Cardiovascular Disease & Diabetes Updated:Jan 29,2018 The following statistics ... clear that there is a strong correlation between cardiovascular disease (CVD) and diabetes. At least 68 percent of ...

  19. Measurement of real pulsatile blood flow using X-ray PIV technique with CO2 microbubbles.

    Science.gov (United States)

    Park, Hanwook; Yeom, Eunseop; Seo, Seung-Jun; Lim, Jae-Hong; Lee, Sang-Joon

    2015-03-06

    Synchrotron X-ray imaging technique has been used to investigate biofluid flows in a non-destructive manner. This study aims to investigate the feasibility of the X-ray PIV technique with CO2 microbubbles as flow tracer for measurement of pulsatile blood flows under in vivo conditions. The traceability of CO2 microbubbles in a pulsatile flow was demonstrated through in vitro experiment. A rat extracorporeal bypass loop was used by connecting a tube between the abdominal aorta and jugular vein of a rat to obtain hemodynamic information of actual pulsatile blood flows without changing the hemorheological properties. The decrease in image contrast of the surrounding tissue was also investigated for in vivo applications of the proposed technique. This technique could be used to accurately measure whole velocity field information of real pulsatile blood flows and has strong potential for hemodynamic diagnosis of cardiovascular diseases.

  20. Measurement of real pulsatile blood flow using X-ray PIV technique with CO2 microbubbles

    Science.gov (United States)

    Park, Hanwook; Yeom, Eunseop; Seo, Seung-Jun; Lim, Jae-Hong; Lee, Sang-Joon

    2015-01-01

    Synchrotron X-ray imaging technique has been used to investigate biofluid flows in a non-destructive manner. This study aims to investigate the feasibility of the X-ray PIV technique with CO2 microbubbles as flow tracer for measurement of pulsatile blood flows under in vivo conditions. The traceability of CO2 microbubbles in a pulsatile flow was demonstrated through in vitro experiment. A rat extracorporeal bypass loop was used by connecting a tube between the abdominal aorta and jugular vein of a rat to obtain hemodynamic information of actual pulsatile blood flows without changing the hemorheological properties. The decrease in image contrast of the surrounding tissue was also investigated for in vivo applications of the proposed technique. This technique could be used to accurately measure whole velocity field information of real pulsatile blood flows and has strong potential for hemodynamic diagnosis of cardiovascular diseases. PMID:25744850

  1. Cardiovascular disease in patients with osteogenesis imperfecta

    DEFF Research Database (Denmark)

    Folkestad, Lars; Hald, Jannie Dahl; Gram, Jeppe

    2016-01-01

    BACKGROUND: Osteogenesis imperfecta (OI) is a hereditary connective tissue disease often due to mutations in genes coding for type 1 collagen. Collagen type 1 is important in the development of the heart and vasculature. Little is known about the risk of cardiovascular disease (CVD) in OI...

  2. Aquaporins in Cardiovascular System.

    Science.gov (United States)

    Tie, Lu; Wang, Di; Shi, Yundi; Li, Xuejun

    2017-01-01

    Recent studies have shown that some aquaporins (AQPs ), including AQP1, AQP4, AQP7 and AQP9, are expressed in endothelial cells, vascular smooth muscle cells and heart of cardiovascular system. These AQPs are involved in the cardiovascular function and in pathological process of related diseases, such as cerebral ischemia , congestion heart failure , hypertension and angiogenesis. Therefore, it is important to understand the accurate association between AQPs and cardiovascular system, which may provide novel approaches to prevent and treat related diseases. Here we will discuss the expression and physiological function of AQPs in cardiovascular system and summarize recent researches on AQPs related cardiovascular diseases.

  3. Impaired autoregulation of blood flow in subcutaneous tissue of long-term type 1 (insulin-dependent) diabetic patients with microangiopathy

    DEFF Research Database (Denmark)

    Kastrup, J; Nørgaard, T; Parving, H H

    1985-01-01

    subjects. Blood flow was measured by the local 133Xenon washout technique. Mean arterial blood pressure was reduced by a maximum of 23 mmHg by elevating the limb above heart level and elevating to a maximum of 70 mmHg by head-up tilt; in the latter position venous pressure was kept constant and low...... with clinical microangiopathy, autoregulation of blood flow was impaired, blood flow changing approximately 20% per 10 mmHg change in arterial blood pressure; the slope of the autoregulation curves was significantly higher compared with the two control groups (p less than 0.02). Resting mean arterial blood...

  4. Relationship between infarct tissue characteristics and left ventricular remodeling in patients with versus without early revascularization for acute myocardial infarction as assessed with contrast-enhanced cardiovascular magnetic resonance imaging

    NARCIS (Netherlands)

    Olimulder, Marlon; Olimulder, M.A.G.M.; Galjee, M.A.; Wagenaar, L.J.; van Es, J.; van der Palen, Jacobus Adrianus Maria; von Birgelen, Clemens

    2012-01-01

    Left ventricular (LV) remodeling following myocardial infarction (MI) is the result of complex interactions between various factors, including presence or absence of early revascularization. The impact of early revascularization on the relationship between infarct tissue characteristics and LV

  5. Cocoa, chocolate, and cardiovascular disease.

    Science.gov (United States)

    Galleano, Monica; Oteiza, Patricia I; Fraga, Cesar G

    2009-12-01

    A significant body of evidence demonstrates that diets rich in fruits and vegetables promote health and attenuate, or delay, the onset of various diseases, including cardiovascular disease, diabetes, certain cancers, and several other age-related degenerative disorders. The concept that moderate chocolate consumption could be part of a healthy diet has gained acceptance in past years based on the health benefits ascribed to selected cocoa components. Specifically, cocoa as a plant and chocolate as food contain a series of chemicals that can interact with cell and tissue components, providing protection against the development and amelioration of pathological conditions. The most relevant effects of cocoa and chocolate have been related to cardiovascular disease. The mechanisms behind these effects are still under investigation. However, the maintenance or restoration of vascular NO production and bioavailability and the antioxidant effects are the mechanisms most consistently supported by experimental data. This review will summarize the most recent research on the cardiovascular effects of cocoa flavanols and related compounds.

  6. Multiphoton imaging of cardiovascular structures

    Science.gov (United States)

    Schenke-Layland, Katja; Opitz, Florian; Riemann, Iris; Stock, Ulrich A.; Konig, Karsten

    2004-09-01

    Near infrared (NIR) femtosecond laser imaging systems represent a novel and very promising diagnostic technology for non-invasive cross-sectional analysis of living biological tissues. In this study 3D multiphoton imaging with submicron resolution has been performed for non-invasive analysis of living native and tissue-engineered (TE) heart valves and blood vessels. High-resolution autofluorescence and second harmonic generation (SHG) images of collagenous structures and elastic fibers were demonstrated using multiphoton excitation at two different wavelengths. Non-invasive optical sections have been obtained without the need of staining or embedding. The quality of the resulting three-dimensional images allowed exact differentiation between collagenous structures and elastic fibers. These experimental results are very encouraging for NIR femtosecond laser scanning microscopy as a useful tool for future non-destructive monitoring and characterization of vital and intact TE cardiovascular structures.

  7. KATP Channels in the Cardiovascular System.

    Science.gov (United States)

    Foster, Monique N; Coetzee, William A

    2016-01-01

    KATP channels are integral to the functions of many cells and tissues. The use of electrophysiological methods has allowed for a detailed characterization of KATP channels in terms of their biophysical properties, nucleotide sensitivities, and modification by pharmacological compounds. However, even though they were first described almost 25 years ago (Noma 1983, Trube and Hescheler 1984), the physiological and pathophysiological roles of these channels, and their regulation by complex biological systems, are only now emerging for many tissues. Even in tissues where their roles have been best defined, there are still many unanswered questions. This review aims to summarize the properties, molecular composition, and pharmacology of KATP channels in various cardiovascular components (atria, specialized conduction system, ventricles, smooth muscle, endothelium, and mitochondria). We will summarize the lessons learned from available genetic mouse models and address the known roles of KATP channels in cardiovascular pathologies and how genetic variation in KATP channel genes contribute to human disease. Copyright © 2016 the American Physiological Society.

  8. Biofluid Dynamics in Cardiovascular System

    Science.gov (United States)

    Chung, Hansol; Yoo, Su Jung; Kyung, Richard

    2011-11-01

    Biofluid dynamics is characterized by the study of fluids in biological systems. Common biofluid systems include blood flow in the cardiovascular system and airflow in the lungs. The mathematical modeling of blood flow through the complex geometry of a prosthetic heart valve is a difficult task. In such a problem the complex geometries of the valve must be modeled properly so that they can be studied numerically. The present analysis is performed on a disk-type prosthetic heart valve. The valve is assumed to be in the aortic position and observed the structure of the valve cage influence the flow field near an aortic valve. For the purpose of mathematical modeling, the laminar incompressible two-dimensional steady flow of a homogeneous Newtonian fluid with constant viscosity is assumed. The flow is considered during the greater part of systole when the valve is fully open. Convergent numerical solutions are obtained for Reynolds numbers of 30, 180, 900 and 4500. Stream function, horizontal velocity, vertical velocity and shear stress solutions are computed at every grid point.

  9. Regional cerebral blood flow in various types of brain tumor. Effect of the space-occupying lesion on blood flow in brain tissue close to and remote from tumor site

    DEFF Research Database (Denmark)

    Kuroda, K; Skyhøj Olsen, T; Lassen, N A

    1982-01-01

    Regional cerebral blood flow (rCBF) was measured in 23 patients with brain tumors using the 133Xe intra-carotid injection method and a 254 channel gamma camera. The glioblastomas (4) and astrocytomas (4) all showed hyperemia in the tumor and tumor-near region. This was also seen in several...... meningiomas (4 of 7 cases) in which most of the tumor itself did not receive any isotope. Brain metastases (6) usually had a low flow in the tumor and tumor-near region. The glioblastomas tended to show markedly bending 133Xe wash-out curves pointing to pronounced heterogeneity of blood flow. Most of the flow...... maps, regardless of the tumor types, showed widespread abnormalities of rCBF not only in the tumor region but also in the region remote from the tumor. It is concluded that measurement of rCBF cannot yield accurate differential diagnostic information, but that the widespread derangement of the brain...

  10. Cardiovascular risk factors and collateral artery formation.

    Science.gov (United States)

    de Groot, D; Pasterkamp, G; Hoefer, I E

    2009-12-01

    Arterial lumen narrowing and vascular occlusion is the actual cause of morbidity and mortality in atherosclerotic disease. Collateral artery formation (arteriogenesis) refers to an active remodelling of non-functional vascular anastomoses to functional collateral arteries, capable to bypass the site of obstruction and preserve the tissue that is jeopardized by ischaemia. Hemodynamic forces such as shear stress and wall stress play a pivotal role in collateral artery formation, accompanied by the expression of various cytokines and invasion of circulating leucocytes. Arteriogenesis hence represents an important compensatory mechanism for atherosclerotic vessel occlusion. As arteriogenesis mostly occurs when lumen narrowing by atherosclerotic plaques takes place, presence of cardiovascular risk factors (e.g. hypertension, hypercholesterolaemia and diabetes) is highly likely. Risk factors for atherosclerotic disease affect collateral artery growth directly and indirectly by altering hemodynamic forces or influencing cellular function and proliferation. Adequate collateralization varies significantly among atherosclerotic patients, some profit from the presence of extensive collateral networks, whereas others do not. Cardiovascular risk factors could increase the risk of adverse cardiovascular events in certain patients because of the reduced protection through an alternative vascular network. Likewise, drugs primarily thought to control cardiovascular risk factors might contribute or counteract collateral artery growth. This review summarizes current knowledge on the influence of cardiovascular risk factors and the effects of cardiovascular medication on the development of collateral vessels in experimental and clinical studies.

  11. MENOPAUSE AND CARDIOVASCULAR RISK

    Directory of Open Access Journals (Sweden)

    D. A. Anichkov

    2005-01-01

    Full Text Available A role of menopause as a cardiovascular risk factor is reviewed. Menopause influence on the cardiovascular system may be mediated by body fat re-allocation, metabolic, hemodynamic and pro-inflammatory changes. Besides, estrogen deprivation has a direct effect on the arterial wall. Lifestyle modification, lipid-lowering and antihypertensive treatment should be considered for cardiovascular risk reduction in postmenopausal women.

  12. Cardiovascular molecular MR imaging

    OpenAIRE

    Lamb, H. J.; van der Meer, R. W.; de Roos, A.; Bax, J. J.

    2007-01-01

    Introduction Cardiovascular molecular imaging is a rapidly evolving field of research, aiming to image and quantify molecular and cellular targets in vivo. MR imaging has some inherent properties that make it very suitable for cardiovascular molecular imaging. Until now, only a limited number of studies have been published on cardiovascular molecular imaging using MR imaging. Review In the current review, MR techniques that have already shown potential are discussed. Metabolic MR imaging can ...

  13. Research in cardiovascular care

    DEFF Research Database (Denmark)

    Jaarsma, Tiny; Deaton, Christi; Fitzsimmons, Donna

    2014-01-01

    with the increasing opportunities and challenges in multidisciplinary research, the Science Committee of the Council on Cardiovascular Nursing and Allied Professionals (CCNAP) recognised the need for a position statement to guide researchers, policymakers and funding bodies to contribute to the advancement...... of the body of knowledge that is needed to further improve cardiovascular care. In this paper, knowledge gaps in current research related to cardiovascular patient care are identified, upcoming challenges are explored and recommendations for future research are given....

  14. Control aspects of the human cardiovascular-respiratory system under a nonconstant workload.

    Science.gov (United States)

    Calderon, Pio Gabrielle B; Habib, Mustafa; Kappel, Franz; de Los Reyes, Aurelio A

    2017-07-01

    The human cardiovascular system (CVS) and respiratory system (RS) work together in order to supply oxygen (O 2 ) and other substrates needed for metabolism and to remove carbon dioxide (CO 2 ). Global and local control mechanisms act on the CVS in order to adjust blood flow to the different parts of the body. This, in turn, affects the RS since the amount of O 2 and CO 2 transported, respectively to and away from the tissues depends on the cardiac output and blood flow in both the systemic and pulmonary circuits of the CVS. Local metabolic control is influenced by local concentrations of blood gases affecting systemic resistance, resulting to vasoconstriction/vasodilation. Thus, the exchange of blood gases demands a tight coordination between blood flow and ventilation of the lungs. In this work, a model of the cardiovascular-respiratory system (CVRS) is considered to obtain an optimal control for time-dependent ergometric workloads by using the Euler-Lagrange formulation of the optimal control problem. The essential controls in the CVRS model are variations in the heart rate and alveolar ventilation through which the central nervous system restricts the arterial partial pressure of CO 2 ( [Formula: see text] ) close to 40  mmHg. Further, penalization terms in the cost functional are included to match the metabolic need for O 2 and the metabolic production of CO 2 with O 2 - and CO 2 -transport by blood. Copyright © 2017. Published by Elsevier Inc.

  15. Successes and future outlook for microfluidics-based cardiovascular drug discovery.

    Science.gov (United States)

    Skommer, Joanna; Wlodkowic, Donald

    2015-03-01

    The greatest advantage of using microfluidics as a platform for the assessment of cardiovascular drug action is its ability to finely regulate fluid flow conditions, including flow rate, shear stress and pulsatile flow. At the same time, microfluidics provide means for modifying the vessel geometry (bifurcations, stenoses, complex networks), the type of surface of the vessel walls, and for patterning cells in 3D tissue-like architecture, including generation of lumen walls lined with cells and heart-on-a-chip structures for mimicking ventricular cardiomyocyte physiology. In addition, owing to the small volume of required specimens, microfluidics is ideally suited to clinical situations whereby monitoring of drug dosing or efficacy needs to be coupled with minimal phlebotomy-related drug loss. In this review, the authors highlight potential applications for the currently existing and emerging technologies and offer several suggestions on how to close the development cycle of microfluidic devices for cardiovascular drug discovery. The ultimate goal in microfluidics research for drug discovery is to develop 'human-on-a-chip' systems, whereby several organ cultures, including the vasculature and the heart, can mimic complex interactions between the organs and body systems. This would provide in vivo-like pharmacokinetics and pharmacodynamics for drug ADMET assessment. At present, however, the great variety of available designs does not go hand in hand with their use by the pharmaceutical community.

  16. Multisite Tissue Oxygenation Monitoring Indicates Organ-Specific Flow Distribution and Oxygen Delivery Related to Low Cardiac Output in Preterm Infants With Clinical Sepsis

    NARCIS (Netherlands)

    van der Laan, Michelle E.; Roofthooft, Marcus T. R.; Fries, Marian W. A.; Schat, Trijntje E.; Bos, Arend F.; Berger, Rolf M. F.; Kooi, Elisabeth M. W.

    Objectives: Cardiac output may be compromised in preterm infants with sepsis. Whether low cardiac output is associated with low tissue oxygen supply in these patients is unclear. The aim of the current study was to assess the association between cardiac output, assessed by echocardiography, and

  17. Pigmented lesions of the oral mucosa and perioral tissues: a flow-chart for the diagnosis and some recommendations for the management

    NARCIS (Netherlands)

    Meleti, M.; Vescovi, P.; Mooi, W.J.; van der Waal, I.

    2008-01-01

    The term "pigmentation of the oral mucosa" is applied to a wide range of lesions or conditions featuring a change of color of oral tissues. Lesions not associated with an accumulation of pigment (e.g., Fordyce spots) are usually not classified as pigmented lesions. Two groups of pigmented lesions of

  18. Multiscale coupling of a Lattice Boltzmann simulation of blood flow to cell- and tissue-level processes: the case of in-stent restenosis

    NARCIS (Netherlands)

    Hoekstra, A.G.; Pereira, J.C.F.; Sequeira, A.; Pereira, J.M.C.

    2010-01-01

    In-stent restenosis, the maladaptive response of a blood vessel to injury caused by the deployment of a stent, is a multiscale system involving a large number of biological and physical processes. We describe a Complex Automata Model for in-stent restenosis, coupling blood flow, drug diffusion, and

  19. The effect of non-esterified long-chain fatty acids on blood flow and thermogenesis in brown adipose tissue in the young dog

    DEFF Research Database (Denmark)

    Astrup, A; Bülow, J; Christensen, N J

    1985-01-01

    level. Plasma noradrenaline concentration increased about three-fold and plasma adrenaline concentration about six-fold. The BAT temperature increased by an average of 0.9 degrees C. However, since BAT blood flow was simultaneously reduced by about 50%, it can be calculated that the local heat...

  20. Cardiovascular risk calculation

    African Journals Online (AJOL)

    James A. Ker

    2014-08-20

    Aug 20, 2014 ... Introduction. Cardiovascular disease remains a major cause of global mortality and morbidity. Atherosclerosis is the main underlying cause in the majority of cardiovascular disease events. Traditional independent risk factors for car diovascular disease include age, abnormal lipid levels, elevated blood ...

  1. Leptin: a cardiovascular perspective

    African Journals Online (AJOL)

    Review Article: Leptin: a cardiovascular perspective. 72. 2012 Volume 17 No 2. JEMDSA. Introduction. Within the realms of noncommunicable disease development in South Africa, obesity is a disease that causes concern. This especially holds true for type 2 diabetes and cardiovascular diseases. Disheartened.

  2. Postirradiation cardiovascular dysfunction

    International Nuclear Information System (INIS)

    Hawkins, R.N.; Cockerham, L.G.

    1987-01-01

    Cardiovascular dysfunction may be defined as the inability of any element of the cardiovascular system to perform adequately upon demand, leading to inadequate performance and nutritive insufficiency of various parts of the body. Exposure to supralethal doses of radiation (accidental and therapeutic) has been show to induce significant alterations in cardiovascular function in man. These findings indicate that, after irradiation, cardiovascular function is a major determinant of continued performance and even survival. For the two persons who received massive radiation doses (45 and 88 Gy, respectively) in criticality accidents, the inability to maintain systematic arterial blood pressure (AP) was the immediate cause of death. In a study of cancer patients given partial-body irradiation, two acute lethalities were attributed to myocardial infarction after an acute hypotensive episode during the first few hours postexposure. Although radiation-induced cardiovascular dysfunction has been observed in many species, its severity, duration, and even etiology may vary with the species, level of exposure, and dose rate. For this reason, our consideration of the effects of radiation on cardiovascular performance is limited to the circulatory derangements that occur in rat, dog, and monkey after supralethal doses and lead to radiation-induced cardiovascular dysfunction in these experimental models. The authors consider other recent data as they pertain to the etiology of cardiovascular dysfunction in irradiated animals

  3. Lifestyle in Cardiovascular Disease

    NARCIS (Netherlands)

    J.O. Younge (John)

    2015-01-01

    markdownabstract__Abstract__ Globally, the burden of cardiovascular disease (CVD) is still increasing. However, in recent decades, better treatment modalities have led to less cardiovascular related deaths. After years of research, we now generally accept that lifestyle factors are the most

  4. Triglycerides and cardiovascular disease

    DEFF Research Database (Denmark)

    Nordestgaard, Børge G; Varbo, Anette

    2014-01-01

    cholesterol might not cause cardiovascular disease as originally thought has now generated renewed interest in raised concentrations of triglycerides. This renewed interest has also been driven by epidemiological and genetic evidence supporting raised triglycerides, remnant cholesterol, or triglyceride......-rich lipoproteins as an additional cause of cardiovascular disease and all-cause mortality. Triglycerides can be measured in the non-fasting or fasting states, with concentrations of 2-10 mmol/L conferring increased risk of cardiovascular disease, and concentrations greater than 10 mmol/L conferring increased risk...... of acute pancreatitis and possibly cardiovascular disease. Although randomised trials showing cardiovascular benefit of triglyceride reduction are scarce, new triglyceride-lowering drugs are being developed, and large-scale trials have been initiated that will hopefully provide conclusive evidence...

  5. Diastolic dysfunction, cardiovascular aging, and the anesthesiologist.

    Science.gov (United States)

    Sanders, David; Dudley, Michael; Groban, Leanne

    2009-09-01

    As the number of persons aged 65 years and older continues to increase, the anesthesiologist will more frequently encounter this demographic. Cardiovascular changes that occur in this patient population present difficult anesthetic challenges and place these patients at high risk of perioperative morbidity and mortality. The anesthesiologist should be knowledgeable about these age-related cardiovascular changes, the pathophysiology underlying them, and the appropriate perioperative management. Whether presenting for cardiac or general surgery, the anesthesiologist must identify patients with altered physiology as a result of aging or diastolic dysfunction and be prepared to modify the care plan accordingly. With a directed preoperative assessment that focuses on certain aspects of the cardiovascular system, and the assistance of powerful echocardiographic tools such as tissue Doppler, this can be achieved.

  6. Analysis of the dynamics of venous blood flow in the context of lower limb temperature distribution and tissue composition in the elderly

    Directory of Open Access Journals (Sweden)

    Skomudek A

    2017-08-01

    Full Text Available Aleksandra Skomudek,1,2 Iwona Gilowska,1,3 Ryszard Jasiński,4 Krystyna Rożek-Piechura4 1Department of Physical Education and Physiotherapy, Opole University of Technology, Opolskie, 2Department of Clinical Physiotherapy, 3Department of Biochemistry and Physiology, 4Department of Physiotherapy and Occupational Therapy in Conservative and Interventional Medicine, University of Physical Education in Wroclaw, Wroclaw, Poland Objective: The elderly are particularly vulnerable to degenerative diseases, such as circulatory and respiratory system and vascular system diseases. The objective of this study was therefore to evaluate the distribution of temperature and the dynamics of venous blood flow in the lower limbs (LLs and to assess the interdependence of these parameters in terms of the somatic components in males and females participating in activities at the University of the Third Age. Materials and methods: The study included 60 females (mean age 67.4 years and 40 males (mean age 67.5 years. A body composition assessment was performed using the bioimpedance technique – Tanita BC-418MA. The following parameters were examined: fat%, fat mass, fat-free mass, and total body water. The minimal, maximal, and mean temperature values and their distributions were examined using infrared thermographic camera VarioCAM Head. Measurements of the venous refilling time and the work of the LL venous pump were examined using a Rheo Dopplex II PPG. Results: In males, the mean value of the right LL temperature was 30.58 and the mean value of the left LL was 30.28; the P-value was 0.805769. In females, the mean value of the right LL temperature was 29.58 and the mean value of the left limb was 29.52; the P-value was 0.864773. In males, the right limb blood flow was 34.17 and the left limb blood flow was 34.67; the P-value was 0.359137. In females, the right limb blood flow was 26.89 and the left limb blood flow was 26.09; the P-value was 0.796348. Conclusion

  7. Clinical Application of Stem Cells in the Cardiovascular System

    Science.gov (United States)

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

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

  8. Cardiovascular response to combined dynamic and static exercise.

    Science.gov (United States)

    Kilbom, A; Persson, J

    1981-06-01

    The cardiovascular response to combined static handgrip at 20% MVC and dynamic leg exercise was studied in young male subjects. Cardiac output increased by 2.3 liters/min (30%) at isolated handgrip and by 1.0 liter/min (7%) when handgrip was added to dynamic exercise at 100 W. In spite of an increased arterial blood pressure, leg blood flow was unaffected by handgrip, both when it was performed isolated and in combination with dynamic exercise. Temperature measurements in mixed venous blood and subcutaneous tissue indicated an increased blood flow to peripheral circulatory areas. During combinations of handgrip and dynamic exercise at different levels of VO2, heart rate response to handgrip was progressively less marked as maximal oxygen uptake was approached. Therefore a vagal withdrawal seems to be the most important heart rate-increasing mechanism during combined exercise. Systolic blood pressure response to handgrip was still preserved at 25 and 45% of max VO2. At 95% of max VO2, the blood pressure response to handgrip was abolished, probably due to a competitive utilization of the same blood pressure-raising mechanism in dynamic and static exercise.

  9. Introduction: Cardiovascular physics.

    Science.gov (United States)

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

    2007-03-01

    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.

  10. [Cancer and cardiovascular disease].

    Science.gov (United States)

    Lahoz, Carlos; Valdivielso, Pedro; González-Alegre, María Teresa; García-Iglesias, María Francisca; Estirado, Eva; Mostaza, José M

    2015-01-01

    Survivors of cancer have a shorter survival in the long term partly due to the increase in cardiovascular diseases (CVD). Some chemotherapy drugs, thoracic and cranial radiotherapy and above all the transplantation of hematopoietic cells are associated with an increase in the incidence of cardiovascular events compared with general population. Some of these treatments favor the development of a metabolic syndrome that could be the intermediary between these treatments and the development of CVD. It is recommended for cancer survivors to promote healthy lifestyles and the strict control of cardiovascular risk factors. Copyright © 2015 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  11. Cardiovascular comorbiditiy in psoriasis

    Directory of Open Access Journals (Sweden)

    Gurcharan Singh

    2011-01-01

    Full Text Available The chronic inflammatory nature of psoriasis is also thought to predispose patients to other diseases with an inflammatory component, the most notable being cardiovascular and metabolic (cardiometabolite disorders. This concept is supported by studies showing that psoriasis is associated with cardiovascular risk factors like diabetes, obesity, hypertension, dyslipidemia, smoking and diseases including MI. Given the increased prevalence of cardiovascular co morbidities in patients, dermatologists treating psoriasis need to approach the disease as a potentially multisystem disorder and must alert these patients to the potentially negative effects of their disease.

  12. Cardiovascular complications of cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Henriksen, Jens Henrik Sahl

    2008-01-01

    Cardiovascular complications of cirrhosis include cardiac dysfunction and abnormalities in the central, splanchnic and peripheral circulation, and haemodynamic changes caused by humoral and nervous dysregulation. Cirrhotic cardiomyopathy implies systolic and diastolic dysfunction and electrophysi......Cardiovascular complications of cirrhosis include cardiac dysfunction and abnormalities in the central, splanchnic and peripheral circulation, and haemodynamic changes caused by humoral and nervous dysregulation. Cirrhotic cardiomyopathy implies systolic and diastolic dysfunction....... The clinical significance of cardiovascular complications and cirrhotic cardiomyopathy is an important topic for future research, and the initiation of new randomised studies of potential treatments for these complications is needed....

  13. Cardiovascular involvement in myositis

    DEFF Research Database (Denmark)

    Diederichsen, Louise P

    2017-01-01

    PURPOSE OF REVIEW: The purpose of this review is to provide an update on cardiovascular involvement in idiopathic inflammatory myopathy (IIM). Studies from the past 18 months are identified and reviewed. Finally, the clinical impact of these findings is discussed. RECENT FINDINGS: Epidemiological...... on cardiac magnetic resonance (CMR) imaging suggests that CMR should be considered as a potentially viable diagnostic tool to evaluate the possibility of silent myocardial inflammation in IIM with normal routine noninvasive evaluation. SUMMARY: Updated literature on cardiovascular involvement in IIM has...... identified an increased risk for subclinical and clinical cardiovascular disease in these rare inflammatory muscle diseases....

  14. Crowdfunding for cardiovascular research.

    Science.gov (United States)

    Krittanawong, Chayakrit; Zhang, HongJu Janet; Aydar, Mehmet; Wang, Zhen; Sun, Tao

    2018-01-01

    The competition for public cardiovascular research grants has recently increased. Independent researchers are facing increasing competition for public research grant support and ultimately may need to seek alternative funding sources. Crowdfunding, a financing method of raising funds online by pooling together small donations from the online community to support a specific initiative, seems to have significant potential. However, the feasibility of crowdfunding for cardiovascular research remains unknown. Here, we performed exploratory data analysis of the feasibility of online crowdfunding in cardiovascular research. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Cell death in the cardiovascular system

    Science.gov (United States)

    Clarke, Murray; Bennett, Martin; Littlewood, Trevor

    2007-01-01

    Cell death is important for both development and tissue homeostasis in the adult. As such, it is tightly controlled and deregulation is associated with diverse pathologies; for example, regulated cell death is involved in vessel remodelling during development or following injury, but deregulated death is implicated in pathologies such as atherosclerosis, aneurysm formation, ischaemic and dilated cardiomyopathies and infarction. We describe the mechanisms of cell death and its role in the normal physiology and various pathologies of the cardiovascular system. PMID:16547202

  16. UK Biobank's cardiovascular magnetic resonance protocol.

    Science.gov (United States)

    Petersen, Steffen E; Matthews, Paul M; Francis, Jane M; Robson, Matthew D; Zemrak, Filip; Boubertakh, Redha; Young, Alistair A; Hudson, Sarah; Weale, Peter; Garratt, Steve; Collins, Rory; Piechnik, Stefan; Neubauer, Stefan

    2016-02-01

    UK Biobank's ambitious aim is to perform cardiovascular magnetic resonance (CMR) in 100,000 people previously recruited into this prospective cohort study of half a million 40-69 year-olds. We describe the CMR protocol applied in UK Biobank's pilot phase, which will be extended into the main phase with three centres using the same equipment and protocols. The CMR protocol includes white blood CMR (sagittal anatomy, coronary and transverse anatomy), cine CMR (long axis cines, short axis cines of the ventricles, coronal LVOT cine), strain CMR (tagging), flow CMR (aortic valve flow) and parametric CMR (native T1 map). This report will serve as a reference to researchers intending to use the UK Biobank resource or to replicate the UK Biobank cardiovascular magnetic resonance protocol in different settings.

  17. Cardiovascular system simulation in biomedical engineering education.

    Science.gov (United States)

    Rideout, V. C.

    1972-01-01

    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.

  18. Radiation-induced cardiovascular effects

    Science.gov (United States)

    Tapio, Soile

    Recent epidemiological studies indicate that exposure to ionising radiation enhances the risk of cardiovascular mortality and morbidity in a moderate but significant manner. Our goal is to identify molecular mechanisms involved in the pathogenesis of radiation-induced cardiovascular disease using cellular and mouse models. Two radiation targets are studied in detail: the vascular endothelium that plays a pivotal role in the regulation of cardiac function, and the myocardium, in particular damage to the cardiac mitochondria. Ionising radiation causes immediate and persistent alterations in several biological pathways in the endothelium in a dose- and dose-rate dependent manner. High acute and cumulative doses result in rapid, non-transient remodelling of the endothelial cytoskeleton, as well as increased lipid peroxidation and protein oxidation of the heart tissue, independent of whether exposure is local or total body. Proteomic and functional changes are observed in lipid metabolism, glycolysis, mitochondrial function (respiration, ROS production etc.), oxidative stress, cellular adhesion, and cellular structure. The transcriptional regulators Akt and PPAR alpha seem to play a central role in the radiation-response of the endothelium and myocardium, respectively. We have recently started co-operation with GSI in Darmstadt to study the effect of heavy ions on the endothelium. Our research will facilitate the identification of biomarkers associated with adverse cardiac effects of ionising radiation and may lead to the development of countermeasures against radiation-induced cardiac damage.

  19. APOE Genotyping, Cardiovascular Disease

    Science.gov (United States)

    ... it ordered? As a test to evaluate lipid metabolism or cardiovascular risk, APOE genotyping is ordered when someone has: Significantly elevated cholesterol and triglyceride levels that do not respond to dietary and ...

  20. The Impact of Autophagy on Cardiovascular Senescence and Diseases.

    Science.gov (United States)

    Sasaki, Yuichi; Ikeda, Yoshiyuki; Iwabayashi, Masaaki; Akasaki, Yuichi; Ohishi, Mitsuru

    2017-10-21

    The risk of cardiovascular disease increases with age, causing chronic disability, morbidity, and mortality in the elderly. Cardiovascular aging and disease are characterized by heart failure, cardiac ischemia-reperfusion injury, cardiomyopathy, hypertension, arterial stiffness, and atherosclerosis. As a cell ages, damaged organelles and abnormal proteins accumulate. A system for removing these cytoplasmic substrates is essential for maintaining homeostasis. Autophagy assists tissue homeostasis by forming a pathway by which these substances are degraded. Growing evidence suggests that autophagy plays a role in age-related and disease states of the cardiovascular system, and it may even be effective in preventing or treating cardiovascular disease. On the other hand, overexpression of autophagy in the heart and arteries can produce detrimental effects. We summarize the current understanding of the close relationship between autophagy and cardiovascular senescence.

  1. Violence and Cardiovascular Health

    Science.gov (United States)

    Suglia, Shakira F.; Sapra, Katherine J.; Koenen, Karestan C.

    2014-01-01

    Context Violence, experienced in either childhood or adulthood, has been associated with physical health outcomes including cardiovascular disease. However, the consistency of the existing literature has not been evaluated. Evidence acquisition In 2013, the authors conducted a PubMed and Web of Science review of peer reviewed articles published prior to August 2013 on the relation between violence exposure, experienced in either childhood or adulthood, and cardiovascular outcomes. To meet inclusion criteria, articles had to present estimates for the relation between violence exposure and cardiovascular outcomes (hypertension, blood pressure, stroke, coronary disease, or myocardial infarction) adjusted for demographic factors. Articles focusing on violence from TV, video games, natural disasters, terrorism, or war were excluded. Evidence synthesis The initial search yielded 2,273 articles; after removing duplicates and applying inclusion and exclusion criteria, 30 articles were selected for review. A consistent positive relation was noted on the association between violence experienced during childhood and cardiovascular outcomes in adulthood (i.e., hypertension, coronary heart disease, and myocardial infarction). Associations across genders with varying types of violence exposure were also noted. By contrast, findings were mixed on the relation between adult violence exposure and cardiovascular outcome. Conclusions Despite varying definitions of violence exposure and cardiovascular endpoints, a consistent relation exists between childhood violence exposure, largely assessed retrospectively, and cardiovascular endpoints. Findings are mixed for the adult violence–cardiovascular health relation. The cross-sectional nature of most adult studies and the reliance of self-reported outcomes can potentially be attributed to the lack of findings among adult violence exposure studies. PMID:25599905

  2. Cardiovascular physiology misconceptions and the potential of cardiovascular physiology teaching to alleviate these.

    Science.gov (United States)

    Palizvan, Mohammad Reza; Nejad, Mohammad Reza Taheri; Jand, Abolfazl; Rafeie, Mohammad

    2013-06-01

    Misconceptions are mental models of phenomena that are at variance with accepted scientific models of these phenomena. The goal of this study was to investigate the prevalence of some misconceptions among students about cardiovascular physiology and to evaluate the effectiveness of cardiovascular physiology teaching in alleviating these misconceptions. A descriptive-analytic survey was undertaken with 348 undergraduates from the fields of medicine, nursing, and biology. Students were divided into two groups on the basis of whether they had passed or not taken the cardiovascular physiology course. The students were asked to answer four questions relating to cardiovascular. Descriptive statistic analysis and two-tailed comparison of the proportions was used to analyze their answers. The prevalence of misconceptions about the left ventricular output versus the right ventricular output ranged from 80% to 98%. The misconception about pulse velocity compared with blood velocity in the vessels was 74% to 89%. Between 95% and 99% of answers to the effect of increased resistance on blood flow were incorrect in all groups. Between 69% and 73% of the students had trouble answering the question on parallel resistance and the effect of the removal of one limb on total peripheral resistance. For most of the questions, university lectures had no effect on alleviating these misconceptions. These results indicate that there is a high prevalence of misconceptions among students about at least four cardiovascular concepts associated with cardiovascular physiology and that teaching has failed to alleviate these misconceptions.

  3. Marijuana Use and Cardiovascular Disease.

    Science.gov (United States)

    Franz, Christopher A; Frishman, William H

    2016-01-01

    Marijuana is currently the most used illicit substance in the world. With the current trend of decriminalization and legalization of marijuana in the US, physicians in the US will encounter more patients using marijuana recreationally over a diverse range of ages and health states. Therefore, it is relevant to review marijuana's effects on human cardiovascular physiology and disease. Compared with placebo, marijuana cigarettes cause increases in heart rate, supine systolic and diastolic blood pressures, and forearm blood flow via increased sympathetic nervous system activity. These actions increase myocardial oxygen demand to a degree that they can decrease the time to exercise-induced angina in patients with a history of stable angina. In addition, marijuana has been associated with triggering myocardial infarctions (MIs) in young male patients. Smoking marijuana has been shown to increase the risk of MI onset by a factor of 4.8 for the 60 minutes after marijuana consumption, and to increase the annual risk of MI in the daily cannabis user from 1.5% to 3% per year. Human and animal models suggest that this effect may be due to coronary arterial vasospasm. However, longitudinal studies have indicated that marijuana use may not have a significant effect on long-term mortality. While further research is required to definitively determine the impact of marijuana on cardiovascular disease, it is reasonable to recommend against recreational marijuana use, especially in individuals with a history of coronary artery disorders.

  4. Autophagy in health and disease: focus on the cardiovascular system.

    Science.gov (United States)

    Mialet-Perez, Jeanne; Vindis, Cécile

    2017-12-12

    Autophagy is a highly conserved mechanism of lysosome-mediated protein and organelle degradation that plays a crucial role in maintaining cellular homeostasis. In the last few years, specific functions for autophagy have been identified in many tissues and organs. In the cardiovascular system, autophagy appears to be essential to heart and vessel homeostasis and function; however defective or excessive autophagy activity seems to contribute to major cardiovascular disorders including heart failure (HF) or atherosclerosis. Here, we review the current knowledge on the role of cardiovascular autophagy in physiological and pathophysiological conditions. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  5. Fibulins and Their Role in Cardiovascular Biology and Disease

    DEFF Research Database (Denmark)

    Cangemi, Claudia; Hansen, Maria Lyck; Argraves, William Scott

    2014-01-01

    Fibulins are a group of extracellular matrix proteins of which many are present in high amounts in the cardiovascular system. They share common biochemical properties and are often found in relation to basement membranes or elastic fibers. Observations in humans with specific mutations in fibulin...... genes, together with results from genetically engineered mice and data from human cardiovascular tissue suggest that the fibulin family of proteins play important functional roles in the cardiovascular system. Moreover, fibulin-1 circulates in high concentrations in plasma and may function...

  6. Adipokines and the cardiovascular system: mechanisms mediating health and disease.

    Science.gov (United States)

    Northcott, Josette M; Yeganeh, Azadeh; Taylor, Carla G; Zahradka, Peter; Wigle, Jeffrey T

    2012-08-01

    This review focuses on the role of adipokines in the maintenance of a healthy cardiovascular system, and the mechanisms by which these factors mediate the development of cardiovascular disease in obesity. Adipocytes are the major cell type comprising the adipose tissue. These cells secrete numerous factors, termed adipokines, into the blood, including adiponectin, leptin, resistin, chemerin, omentin, vaspin, and visfatin. Adipose tissue is a highly vascularised endocrine organ, and different adipose depots have distinct adipokine secretion profiles, which are altered with obesity. The ability of many adipokines to stimulate angiogenesis is crucial for adipose tissue expansion; however, excessive blood vessel growth is deleterious. As well, some adipokines induce inflammation, which promotes cardiovascular disease progression. We discuss how these 7 aforementioned adipokines act upon the various cardiovascular cell types (endothelial progenitor cells, endothelial cells, vascular smooth muscle cells, pericytes, cardiomyocytes, and cardiac fibroblasts), the direct effects of these actions, and their overall impact on the cardiovascular system. These were chosen, as these adipokines are secreted predominantly from adipocytes and have known effects on cardiovascular cells.

  7. Range of control of cardiovascular variables by the hypothalamus

    Science.gov (United States)

    Smith, O. A.; Stephenson, R. B.; Randall, D. C.

    1974-01-01

    New methodologies were utilized to study the influence of the hypothalamus on the cardiovascular system. The regulation of myocardial activity was investigated in monkeys with hypothalamic lesions that eliminate cardiovascular responses. Observations showed that a specific part of the hypothalamus regulates changes in myocardial contractility that accompanies emotion. Studies of the hypothalamus control of renal blood flow showed the powerful potential control of this organ over renal circulation.

  8. Stem Cells in Cardiovascular Medicine: the Road to Regenerative Therapies.

    Science.gov (United States)

    Anderson, Christopher W; Boardman, Nicole; Luo, Jiesi; Park, Jinkyu; Qyang, Yibing

    2017-04-01

    The purpose of this review is to provide a broad overview of current trends in stem cell research and its applications in cardiovascular medicine. Researches on different stem cell sources, their inherent characteristics, and the limitations they have in medical applications are discussed. Additionally, uses of stem cells for both modeling and treating cardiovascular disease are discussed, taking note of the obstacles these engineered interventions must overcome to be clinically viable. Tissue engineering aims to replace dysfunctional tissues with engineered constructs. Stem cell technologies have been a great enabling factor in working toward this goal. Many tissue-engineered products are in development that utilize stem cell technology. Although promising, some refinement must be made to these constructs with respect to safety and functionality. A deeper understanding of basic differentiation and tissue developmental mechanisms is required to allow these engineered tissues to be translated into the clinic.

  9. Cardiovascular Fat, Menopause, and Sex Hormones in Women: The SWAN Cardiovascular Fat Ancillary Study.

    Science.gov (United States)

    El Khoudary, Samar R; Shields, Kelly J; Janssen, Imke; Hanley, Carrie; Budoff, Matthew J; Barinas-Mitchell, Emma; Everson-Rose, Susan A; Powell, Lynda H; Matthews, Karen A

    2015-09-01

    Cardiovascular risk increases in women after menopause. Mounting evidence demonstrates a role of cardiovascular fat (CF) in the pathogenesis of coronary heart disease, but no research has examined CF in relation to sex hormones or menopausal status in women. The objective was to determine the relationship between CF depots, menopausal status, and endogenous sex hormones. Cross-sectional and longitudinal study designs were used. The setting included the Study of Women's Health Across the Nation (SWAN) Heart and Cardiovascular Fat Ancillary Study. A total of 456 women (mean age, 50.75 y); 62% premenopausal/early perimenopausal, and 38% late peri-/postmenopausal. Menopausal status, endogenous sex hormones measured simultaneously with CF volumes, and circulating estradiol available 4.80 years (median) before CF measures. Volumes of CF (epicardial adipose tissue [EAT], paracardial adipose tissue [PAT], total heart adipose tissue [TAT = EAT + PAT], and aortic perivascular adipose tissue [PVAT]). In final models, late peri-/postmenopausal women had 9.88% more EAT, 20.72% more PAT, and 11.69% more TAT volumes than pre-/early perimenopausal women (P menopausal status. In final models, lower estradiol concentrations were associated with greater volumes of PAT and TAT (P hormones are associated with CF. Perhaps CF plays a role in the higher risk of coronary heart disease reported in women after menopause.

  10. Envejecimiento del sistema cardiovascular Cardiovascular system aging

    Directory of Open Access Journals (Sweden)

    José M Ocampo

    2005-08-01

    Full Text Available El envejecimiento del sistema cardiovascular está asociado con un número característico de cambios a nivel bioquímico, histológico y morfológico. Sin embargo, no todas las modificaciones presentadas se asocian con deterioro en la función. Entre los cambios a nivel cardiaco se tienen: disminución en el número de miocitos y en las células del sistema de conducción cardiaca, desarrollo de fibrosis, cambios en el transporte de calcio a través de las membranas y disminución del cronotropismo, inotropismo y lusitropismo mediados por estímulo b-adrenérgico. A nivel vascular, hay incremento en la rigidez de la pared de las arterias, con aumento en la velocidad de la onda de pulso, disfunción endotelial y disminución de la vasodilatación mediada por estímulo b-adrenérgico. Durante el reposo el sistema cardiovascular es capaz de desarrollar mecanismos adaptativos eficientes, pero en situaciones de estrés como el ejercicio, los cambios asociados con el envejecimiento se hacen evidentes ya que está disminuida la capacidad para obtener la frecuencia cardiaca máxima, está incrementada la postcarga y hay disminución de la contractilidad intrínseca. Por lo anterior, los ancianos deben utilizar al máximo el mecanismo de Frank-Starling para mantener el gasto cardiaco. Los cambios estructurales y funcionales asociados con el envejecimiento cardiovascular, disminuyen de forma significativa el umbral en el cual las enfermedades cardiacas llegan a ser evidentes, y deben ser conocidos por el personal de salud encargado de cuidar a los ancianos.Cardiovascular aging is associated with characteristic biochemical, histological and morphological changes. Nevertheless, these changes are not necessarily associated to a deterioration in its function. Among the cardiac changes found, there is a reduction in the number of myocytes and of the cardiac conduction system cells, development of fibrosis, changes in the trans-membrane calcium transport and a

  11. Optical monitoring during bioreactor conditioning of tissue-engineered heart valves.

    Science.gov (United States)

    Ziegelmueller, Johannes A; Zaenkert, Eva K; Schams, Rahmin; Lackermair, Stephan; Schmitz, Christoph; Reichart, Bruno; Sodian, Ralf

    2010-01-01

    Currently, one approach to tissue engineering has been to develop in vitro conditions to fabricate functional cardiovascular structures such as heart valves before final implantation. In vivo conditions are simulated using a bioreactor system that supplies cells with oxygen and culture media while providing mechanical stimulation to promote tissue maturation. In our experiment, we developed a novel combined optical monitoring and conditioning device. The entire system is made of acrylic glass and is completely transparent. The bioreactor is connected to an air-driven respirator pump, and the cell culture medium continuously circulates through a closed-loop system. By adjusting stroke volume, stroke rate, and inspiration/expiration time of the ventilator, the system allows various pulsatile flows and different levels of pressure. Our optical monitoring and conditioning device provides a sterile environment, mechanical stimulation, and optical monitoring for the in vitro maturation of a tissue-engineered heart valve. With the camera module attached, tissue-engineered valves can be observed during the entire in vitro phase. This setting helps to find the optimal dynamic conditions for tissue-engineered heart valves to mature by adjusting flow and pressure conditions to provide physiological opening and closing behavior of the heart valve construct.

  12. Ozone and cardiovascular injury

    Directory of Open Access Journals (Sweden)

    Rainaldi Giuseppe

    2009-06-01

    Full Text Available Abstract Air pollution is increasingly recognized as an important and modifiable determinant of cardiovascular diseases in urban communities. The potential detrimental effects are both acute and chronic having a strong impact on morbidity and mortality. The acute exposure to pollutants has been linked to adverse cardiovascular events such as myocardial infarction, heart failure and life-threatening arrhythmias. The long-terms effects are related to the lifetime risk of death from cardiac causes. The WHO estimates that air pollution is responsible for 3 million premature deaths each year. The evidence supporting these data is very strong nonetheless, epidemiologic and observational data have the main limitation of imprecise measurements. Moreover, the lack of clinical experimental models makes it difficult to demonstrate the individual risk. The other limitation is related to the lack of a clear mechanism explaining the effects of pollution on cardiovascular mortality. In the present review we will explore the epidemiological, clinical and experimental evidence of the effects of ozone on cardiovascular diseases. The pathophysiologic consequences of air pollutant exposures have been extensively investigated in pulmonary systems, and it is clear that some of the major components of air pollution (e.g. ozone and particulate matter can initiate and exacerbate lung disease in humans 1. It is possible that pulmonary oxidant stress mediated by particulate matter and/or ozone (O3 exposure can result in downstream perturbations in the cardiovasculature, as the pulmonary and cardiovascular systems are intricately associated, and it is well documented that specific environmental toxins (such as tobacco smoke 2 introduced through the lungs can initiate and/or accelerate cardiovascular disease development. Indeed, several epidemiologic studies have proved that there is an association between PM and O3 and the increased incidence of cardiovascular morbidity

  13. Tissue engineering

    CERN Document Server

    Fisher, John P; Bronzino, Joseph D

    2007-01-01

    Increasingly viewed as the future of medicine, the field of tissue engineering is still in its infancy. As evidenced in both the scientific and popular press, there exists considerable excitement surrounding the strategy of regenerative medicine. To achieve its highest potential, a series of technological advances must be made. Putting the numerous breakthroughs made in this field into a broad context, Tissue Engineering disseminates current thinking on the development of engineered tissues. Divided into three sections, the book covers the fundamentals of tissue engineering, enabling technologies, and tissue engineering applications. It examines the properties of stem cells, primary cells, growth factors, and extracellular matrix as well as their impact on the development of tissue engineered devices. Contributions focus on those strategies typically incorporated into tissue engineered devices or utilized in their development, including scaffolds, nanocomposites, bioreactors, drug delivery systems, and gene t...

  14. The effect of ascorbic acid and fluid flow stimulation on the mechanical properties of a tissue engineered pelvic floor repair material.

    Science.gov (United States)

    Osman, Nadir I; Roman, Sabiniano; Bullock, Anthony J; Chapple, Christopher R; MacNeil, Sheila

    2014-09-01

    Synthetic non-degradable meshes used in pelvic floor surgery can cause serious complications such as tissue erosion. A repair material composed of an autologous oral fibroblast seeded degradable polylactic acid scaffold may be a viable alternative. The aims of this study were to investigate the effects of media supplementation with additives (ascorbic acid-2-phosphate, glycolic acid and 17-β-oestradiol) on the mechanical properties of these scaffolds. Oral fibroblasts were isolated from buccal mucosa. The effects of the three additives were initially compared in two-dimensional culture to select the most promising collagen stimulating additive. Sterile electrospun scaffolds were seeded with 500,000 oral fibroblasts and fixed in 6-well plates and subjected to ascorbic acid-2-phosphate (the best performing additive) and/or mechanical stimulation. Mechanical stimulation by fluid shear stress was induced by rocking scaffolds on a platform shaker for 1 h/day for 10 of 14 days of culture. In two-dimensional culture, ascorbic acid-2-phosphate (concentrations from 0.02 mM to 0.04 M) and glycolic acid (10 µM) led to significantly greater total collagen production, but ascorbic acid-2-phosphate at 0.03 mM produced the greatest stimulation (of the order of >100%). In three-dimensional culture, mechanical stimulation alone gave non-significant increases in stiffness and strength. Ascorbic acid-2-phosphate (0.03 mM) significantly increased collagen production in the order 280% in both static and mechanically stimulated scaffolds (p material with improved mechanical properties can be developed by supplementing culture media with ascorbic acid-2-phosphate to increase collagen I production. Future studies will assess the change in mechanical properties after implantation in an animal model. © IMechE 2014.

  15. Diabetes Drugs and Cardiovascular Safety

    Directory of Open Access Journals (Sweden)

    Ji Cheol Bae

    2016-06-01

    Full Text Available Diabetes is a well-known risk factor of cardiovascular morbidity and mortality, and the beneficial effect of improved glycemic control on cardiovascular complications has been well established. However, the rosiglitazone experience aroused awareness of potential cardiovascular risk associated with diabetes drugs and prompted the U.S. Food and Drug Administration to issue new guidelines about cardiovascular risk. Through postmarketing cardiovascular safety trials, some drugs demonstrated cardiovascular benefits, while some antidiabetic drugs raised concern about a possible increased cardiovascular risk associated with drug use. With the development of new classes of drugs, treatment options became wider and the complexity of glycemic management in type 2 diabetes has increased. When choosing the appropriate treatment strategy for patients with type 2 diabetes at high cardiovascular risk, not only the glucose-lowering effects, but also overall benefits and risks for cardiovascular disease should be taken into consideration.

  16. Accurate Blood Flow Measurements : Are Artificial Tracers Necessary?

    NARCIS (Netherlands)

    Poelma, C.; Kloosterman, A.; Hierck, B.P.; Westerweel, J.

    2012-01-01

    Imaging-based blood flow measurement techniques, such as particle image velocimetry, have become an important tool in cardiovascular research. They provide quantitative information about blood flow, which benefits applications ranging from developmental biology to tumor perfusion studies. Studies

  17. NSAIDs and cardiovascular risk.

    Science.gov (United States)

    Marsico, Fabio; Paolillo, Stefania; Filardi, Pasquale P

    2017-01-01

    NSAIDs are the most largely used class of drugs in the world, due to their large use in many diseases, in particular for the systemic inflammatory diseases. Nevertheless, today NSAIDs are less used for some of these diseases, due to several side-effects correlated to these drugs. The antiinflammatory mechanism of NSAIDs consist in the inibhition of two forms of cyclooxygenase, namely COX-1 (its block contributes to an antiplatelet effect) and COX-2 (its block has a greater antiinflammatory, antipyretic and analgesic effect). The COX-2 inhibition might reduce the risk of gastrointestinal toxicity, but several studies have shown the cardiovascular side effects of this inhibition. Mechanisms of the cardiovascular side effects are controversial yet, so the aim of this document is to review side-effects profile of NSAIDs and, specifically, to investigate cardiovascular consequences of NSAIDs use in clinical practice.

  18. Cardiovascular complications of cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Henriksen, Jens Henrik Sahl

    2008-01-01

    Cardiovascular complications of cirrhosis include cardiac dysfunction and abnormalities in the central, splanchnic and peripheral circulation, and haemodynamic changes caused by humoral and nervous dysregulation. Cirrhotic cardiomyopathy implies systolic and diastolic dysfunction and electrophysi......Cardiovascular complications of cirrhosis include cardiac dysfunction and abnormalities in the central, splanchnic and peripheral circulation, and haemodynamic changes caused by humoral and nervous dysregulation. Cirrhotic cardiomyopathy implies systolic and diastolic dysfunction...... and electrophysiological abnormalities, an entity that is different from alcoholic heart muscle disease. Being clinically latent, cirrhotic cardiomyopathy can be unmasked by physical or pharmacological strain. Consequently, caution should be exercised in the case of stressful procedures, such as large volume paracentesis....... The clinical significance of cardiovascular complications and cirrhotic cardiomyopathy is an important topic for future research, and the initiation of new randomised studies of potential treatments for these complications is needed....

  19. Mitochondria and Cardiovascular Aging

    Science.gov (United States)

    Dai, Dao-Fu; Ungvari, Zoltan

    2013-01-01

    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

  20. Tea and Cardiovascular Disease

    Science.gov (United States)

    Deka, Apranta; Vita, Joseph A.

    2011-01-01

    There is increasing evidence for a protective effect of tea consumption against cardiovascular disease. This review summarizes the available epidemiological data providing evidence for and against such an effect. We also review observational and intervention studies that investigated an effect of tea and tea extracts on cardiovascular risk factors, including blood pressure, serum lipids, diabetes mellitus, and obesity. Finally, we review potential mechanisms of benefit, including anti-inflammatory, anti-oxidant, and anti-proliferative effects, as well as favorable effects on endothelial function. Overall, the observational data suggest a benefit, but results are mixed and likely confounded by lifestyle and background dietary factors. The weight of evidence indicates favorable effects on risk factors and a number of plausible mechanisms have been elucidated in experimental and translational human studies. Despite the growing body evidence, it remains uncertain whether tea consumption should be recommended to the general population or to patients as a strategy to reduce cardiovascular risk. PMID:21477653

  1. Mitochondria and cardiovascular aging.

    Science.gov (United States)

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

    2012-04-13

    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.

  2. Novel biomarkers for cardiovascular risk prediction.

    Science.gov (United States)

    Wang, Juan; Tan, Guo-Juan; Han, Li-Na; Bai, Yong-Yi; He, Miao; Liu, Hong-Bin

    2017-02-01

    Cardiovascular disease (CVD) is the leading cause of death and disability worldwide. The primary prevention of CVD is dependent upon the ability to identify high-risk individuals long before the development of overt events. This highlights the need for accurate risk stratification. An increasing number of novel biomarkers have been identified to predict cardiovascular events. Biomarkers play a critical role in the definition, prognostication, and decision-making regarding the management of cardiovascular events. This review focuses on a variety of promising biomarkers that provide diagnostic and prognostic information. The myocardial tissue-specific biomarker cardiac troponin, high-sensitivity assays for cardiac troponin, and heart-type fatty acid binding proteinall help diagnose myocardial infarction (MI) in the early hours following symptoms. Inflammatory markers such as growth differentiation factor-15, high-sensitivity C-reactive protein, fibrinogen, and uric acid predict MI and death. Pregnancy-associated plasma protein A, myeloperoxidase, and matrix metalloproteinases predict the risk of acute coronary syndrome. Lipoprotein-associated phospholipase A2 and secretory phospholipase A2 predict incident and recurrent cardiovascular events. Finally, elevated natriuretic peptides, ST2, endothelin-1, mid-regional-pro-adrenomedullin, copeptin, and galectin-3 have all been well validated to predict death and heart failure following a MI and provide risk stratification information for heart failure. Rapidly developing new areas, such as assessment of micro-RNA, are also explored. All the biomarkers reflect different aspects of the development of atherosclerosis.

  3. Pharmacogenomics and cardiovascular disease

    DEFF Research Database (Denmark)

    Weeke, Peter; Roden, Dan M

    2013-01-01

    Variability in drug responsiveness is a sine qua non of modern therapeutics, and the contribution of genomic variation is increasingly recognized. Investigating the genomic basis for variable responses to cardiovascular therapies has been a model for pharmacogenomics in general and has established...... resulted in changes to the product labels but also have led to development of initial clinical guidelines that consider how to facilitate incorporating genetic information to the bedside. This review summarizes the state of knowledge in cardiovascular pharmacogenomics and considers how variants described...

  4. Trending Cardiovascular Nutrition Controversies.

    Science.gov (United States)

    Freeman, Andrew M; Morris, Pamela B; Barnard, Neal; Esselstyn, Caldwell B; Ros, Emilio; Agatston, Arthur; Devries, Stephen; O'Keefe, James; Miller, Michael; Ornish, Dean; Williams, Kim; Kris-Etherton, Penny

    2017-03-07

    The potential cardiovascular benefits of several trending foods and dietary patterns are still incompletely understood, and nutritional science continues to evolve. However, in the meantime, a number of controversial dietary patterns, foods, and nutrients have received significant media exposure and are mired by hype. This review addresses some of the more popular foods and dietary patterns that are promoted for cardiovascular health to provide clinicians with accurate information for patient discussions in the clinical setting. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  5. Heat waves, aging, and human cardiovascular health.

    Science.gov (United States)

    Kenney, W Larry; Craighead, Daniel H; Alexander, Lacy M

    2014-10-01

    This brief review is based on a President's Lecture presented at the Annual Meeting of the American College of Sports Medicine in 2013. The purpose of this review was to assess the effects of climate change and consequent increases in environmental heat stress on the aging cardiovascular system. The earth's average global temperature is slowly but consistently increasing, and along with mean temperature changes come increases in heat wave frequency and severity. Extreme passive thermal stress resulting from prolonged elevations in ambient temperature and prolonged physical activity in hot environments creates a high demand on the left ventricle to pump blood to the skin to dissipate heat. Even healthy aging is accompanied by altered cardiovascular function, which limits the extent to which older individuals can maintain stroke volume, increase cardiac output, and increase skin blood flow when exposed to environmental extremes. In the elderly, the increased cardiovascular demand during heat waves is often fatal because of increased strain on an already compromised left ventricle. Not surprisingly, excess deaths during heat waves 1) occur predominantly in older individuals and 2) are overwhelmingly cardiovascular in origin. Increasing frequency and severity of heat waves coupled with a rapidly growing at-risk population dramatically increase the extent of future untoward health outcomes.

  6. Tissue types (image)

    Science.gov (United States)

    There are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue ... and binds them together (bone, blood, and lymph tissues). Epithelial tissue provides a covering (skin, the linings of ...

  7. Molecular, cellular, and tissue engineering

    CERN Document Server

    Bronzino, Joseph D

    2015-01-01

    Known as the bible of biomedical engineering, The Biomedical Engineering Handbook, Fourth Edition, sets the standard against which all other references of this nature are measured. As such, it has served as a major resource for both skilled professionals and novices to biomedical engineering. Molecular, Cellular, and Tissue Engineering, the fourth volume of the handbook, presents material from respected scientists with diverse backgrounds in molecular biology, transport phenomena, physiological modeling, tissue engineering, stem cells, drug delivery systems, artificial organs, and personalized medicine. More than three dozen specific topics are examined, including DNA vaccines, biomimetic systems, cardiovascular dynamics, biomaterial scaffolds, cell mechanobiology, synthetic biomaterials, pluripotent stem cells, hematopoietic stem cells, mesenchymal stem cells, nanobiomaterials for tissue engineering, biomedical imaging of engineered tissues, gene therapy, noninvasive targeted protein and peptide drug deliver...

  8. Reactive oxygen species: players in the cardiovascular effects of testosterone

    Science.gov (United States)

    Carneiro, Fernando S.; Carvalho, Maria Helena C.; Reckelhoff, Jane F.

    2015-01-01

    Androgens are essential for the development and maintenance of male reproductive tissues and sexual function and for overall health and well being. Testosterone, the predominant and most important androgen, not only affects the male reproductive system, but also influences the activity of many other organs. In the cardiovascular system, the actions of testosterone are still controversial, its effects ranging from protective to deleterious. While early studies showed that testosterone replacement therapy exerted beneficial effects on cardiovascular disease, some recent safety studies point to a positive association between endogenous and supraphysiological levels of androgens/testosterone and cardiovascular disease risk. Among the possible mechanisms involved in the actions of testosterone on the cardiovascular system, indirect actions (changes in the lipid profile, insulin sensitivity, and hemostatic mechanisms, modulation of the sympathetic nervous system and renin-angiotensin-aldosterone system), as well as direct actions (modulatory effects on proinflammatory enzymes, on the generation of reactive oxygen species, nitric oxide bioavailability, and on vasoconstrictor signaling pathways) have been reported. This mini-review focuses on evidence indicating that testosterone has prooxidative actions that may contribute to its deleterious actions in the cardiovascular system. The controversial effects of testosterone on ROS generation and oxidant status, both prooxidant and antioxidant, in the cardiovascular system and in cells and tissues of other systems are reviewed. PMID:26538238

  9. Epigenetics and cardiovascular disease

    Science.gov (United States)

    Despite advances in the prevention and management of cardiovascular disease (CVD), this group of multifactorial disorders remains a leading cause of mortality worldwide. CVD is associated with multiple genetic and modifiable risk factors; however, known environmental and genetic influences can only...

  10. Testosterone and Cardiovascular Disease.

    Science.gov (United States)

    Kloner, Robert A; Carson, Culley; Dobs, Adrian; Kopecky, Stephen; Mohler, Emile R

    2016-02-09

    Testosterone (T) is the principal male sex hormone. As men age, T levels typically fall. Symptoms of low T include decreased libido, vasomotor instability, and decreased bone mineral density. Other symptoms may include depression, fatigue, erectile dysfunction, and reduced muscle strength/mass. Epidemiology studies show that low levels of T are associated with more atherosclerosis, coronary artery disease, and cardiovascular events. However, treating hypogonadism in the aging male has resulted in discrepant results in regard to its effect on cardiovascular events. Emerging studies suggest that T may have a future role in treating heart failure, angina, and myocardial ischemia. A large, prospective, long-term study of T replacement, with a primary endpoint of a composite of adverse cardiovascular events including myocardial infarction, stroke, and/or cardiovascular death, is needed. The Food and Drug Administration recently put additional restrictions on T replacement therapy labeling and called for additional studies to determine its cardiac safety. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  11. Cheese and cardiovascular health

    DEFF Research Database (Denmark)

    Hjerpsted, Julie Bousgaard

    Cardiovascular diseases (CVDs) are the number one cause of mortality worldwide. Low-density lipoprotein (LDL) cholesterol is a well-known risk factor of CVD which increases after the intake of saturated fatty acids (SFA). Cheese is a dietary product commonly consumed in Western countries and known...

  12. Cardiovascular risk prediction

    DEFF Research Database (Denmark)

    Graversen, Peter; Abildstrøm, Steen Z.; Jespersen, Lasse

    2016-01-01

    Aim European society of cardiology (ESC) guidelines recommend that cardiovascular disease (CVD) risk stratification in asymptomatic individuals is based on the Systematic Coronary Risk Evaluation (SCORE) algorithm, which estimates individual 10-year risk of death from CVD. We assessed the potential...

  13. Gender and Cardiovascular Disease

    NARCIS (Netherlands)

    Den Ruijter, Hester M.; Pasterkamp, Gerard

    2015-01-01

    More women than men die of cardiovascular disease (CVD) each year in every major developed country and most emerging economies. Nonetheless, CVD has often been considered as men’s disease due to the higher rates of coronary artery disease (CAD) of men at younger age. This has led to the

  14. The Cardiovascular Research Grid (CVRG)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The CardioVascular Research Grid (CVRG) project is creating an infrastructure for sharing cardiovascular data and data analysis tools. CVRG tools are developed using...

  15. Cold Weather and Cardiovascular Disease

    Science.gov (United States)

    ... Venous Thromboembolism Aortic Aneurysm More Cold Weather and Cardiovascular Disease Updated:Sep 16,2015 Th is winter season ... can affect your heart, especially if you have cardiovascular disease . Some people who are outdoors in cold weather ...

  16. [Cardiovascular system and aging].

    Science.gov (United States)

    Saner, H

    2005-12-01

    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.

  17. Pediatric computed tomographic angiography: imaging the cardiovascular system gently.

    Science.gov (United States)

    Hellinger, Jeffrey C; Pena, Andres; Poon, Michael; Chan, Frandics P; Epelman, Monica

    2010-03-01

    Whether congenital or acquired, timely recognition and management of disease is imperative, as hemodynamic alterations in blood flow, tissue perfusion, and cellular oxygenation can have profound effects on organ function, growth and development, and quality of life for the pediatric patient. Ensuring safe computed tomographic angiography (CTA) practice and "gentle" pediatric imaging requires the cardiovascular imager to have sound understanding of CTA advantages, limitations, and appropriate indications as well as strong working knowledge of acquisition principles and image post processing. From this vantage point, CTA can be used as a useful adjunct along with the other modalities. This article presents a summary of dose reduction CTA methodologies along with techniques the authors have employed in clinical practice to achieve low-dose and ultralow-dose exposure in pediatric CTA. CTA technical principles are discussed with an emphasis on the low-dose methodologies and safe contrast medium delivery strategies. Recommended parameters for currently available multidetector-row computed tomography scanners are summarized alongside recommended radiation and contrast medium parameters. In the second part of the article an overview of pediatric CTA clinical applications is presented, illustrating low-dose and ultra-low dose techniques, with an emphasis on the specific protocols. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Nonfasting hyperlipidemia and cardiovascular disease

    DEFF Research Database (Denmark)

    Nordestgaard, B G; Langsted, A; Freiberg, J J

    2009-01-01

    , total cholesterol/HDL cholesterol, and apolipoprotein B/apolipoprotein A1 all associate with increased risk of cardiovascular disease. These new data open the possibility that nonfasting rather than fasting lipid profiles can be used for cardiovascular risk prediction. If implemented, this would...... of cardiovascular disease and early death....

  19. Asian & Pacific Islanders and Cardiovascular Diseases

    Science.gov (United States)

    ... Fact Sheet 2016 Update Asian & Pacific Islanders and Cardiovascular Diseases Cardiovascular Disease (CVD) (ICD 10 codes I00-I99, Q20- ... of na- tive Hawaiians or oth- A indicates cardiovascular disease plus congenital cardiovascular disease (ICD-10 I00- ...

  20. Metabolic syndrome, chronic kidney, and cardiovascular diseases: role of adipokines.

    Science.gov (United States)

    Tesauro, Manfredi; Canale, Maria Paola; Rodia, Giuseppe; Di Daniele, Nicola; Lauro, Davide; Scuteri, Angelo; Cardillo, Carmine

    2011-03-07

    Obesity is a chronic disease, whose incidence is alarmingly growing. It is associated with metabolic abnormalities and cardiovascular complications. These complications are clustered in the metabolic syndrome (MetS) leading to high cardiovascular morbidity and mortality. Obesity predisposes to diabetic nephropathy, hypertensive nephrosclerosis, and focal and segmental glomerular sclerosis and represents an independent risk factor for the development and progression of chronic kidney disease (CKD). Albuminuria is a major risk factor for cardiovascular diseases (CVDs). Microalbuminuria has been described as early manifestation of MetS-associated kidney damage and diabetic nephropathy. Obesity and MetS affect renal physiology and metabolism through mechanisms which include altered levels of adipokines such as leptin and adiponectin, oxidative stress, and inflammation. Secretory products of adipose tissue also deeply and negatively influence endothelial function. A better understanding of these interactions will help in designing more effective treatments aimed to protect both renal and cardiovascular systems.

  1. Metabolic Syndrome, Chronic Kidney, and Cardiovascular Diseases: Role of Adipokines

    Directory of Open Access Journals (Sweden)

    Manfredi Tesauro

    2011-01-01

    Full Text Available Obesity is a chronic disease, whose incidence is alarmingly growing. It is associated with metabolic abnormalities and cardiovascular complications. These complications are clustered in the metabolic syndrome (MetS leading to high cardiovascular morbidity and mortality. Obesity predisposes to diabetic nephropathy, hypertensive nephrosclerosis, and focal and segmental glomerular sclerosis and represents an independent risk factor for the development and progression of chronic kidney disease (CKD. Albuminuria is a major risk factor for cardiovascular diseases (CVDs. Microalbuminuria has been described as early manifestation of MetS-associated kidney damage and diabetic nephropathy. Obesity and MetS affect renal physiology and metabolism through mechanisms which include altered levels of adipokines such as leptin and adiponectin, oxidative stress, and inflammation. Secretory products of adipose tissue also deeply and negatively influence endothelial function. A better understanding of these interactions will help in designing more effective treatments aimed to protect both renal and cardiovascular systems.

  2. Trends in Tissue Engineering for Blood Vessels

    Science.gov (United States)

    Nemeno-Guanzon, Judee Grace; Lee, Soojung; Berg, Johan Robert; Jo, Yong Hwa; Yeo, Jee Eun; Nam, Bo Mi; Koh, Yong-Gon; Lee, Jeong Ik

    2012-01-01

    Over the years, cardiovascular diseases continue to increase and affect not only human health but also the economic stability worldwide. The advancement in tissue engineering is contributing a lot in dealing with this immediate need of alleviating human health. Blood vessel diseases are considered as major cardiovascular health problems. Although blood vessel transplantation is the most convenient treatment, it has been delimited due to scarcity of donors and the patient's conditions. However, tissue-engineered blood vessels are promising alternatives as mode of treatment for blood vessel defects. The purpose of this paper is to show the importance of the advancement on biofabrication technology for treatment of soft tissue defects particularly for vascular tissues. This will also provide an overview and update on the current status of tissue reconstruction especially from autologous stem cells, scaffolds, and scaffold-free cellular transplantable constructs. The discussion of this paper will be focused on the historical view of cardiovascular tissue engineering and stem cell biology. The representative studies featured in this paper are limited within the last decade in order to trace the trend and evolution of techniques for blood vessel tissue engineering. PMID:23251085

  3. Geochemistry of water in relation to cardiovascular disease

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    Relations between trace and major element chemistry of drinking water and cardiovascular diseases are reviewed and documented. Several aspects of the problem, related both to the pathway that drinking water takes to man and to its transit through man, are reviewed. Several steps in the pathogenesis of cardiovascular disease that could be affected by water factors were explored. There is little evidence bearing on the contribution from drinking water to human tissue levels of cadmium, chromium, or zinc. Copper and magnesium levels of tissues may be related to drinking water, but confirmatory evidence is needed. Lead levels in blood and other tissues are most certainly affected by lead levels in drinking water in areas where these levels are unusually elevated. There is little evidence that relatively low levels of lead are toxic to the cardiovascular system, except for the causation of cardiomyopathy. The protective action of selenium and zinc applies mainly to cadmium toxicity. The mode of the protective action of silicon, if any, is unclear at present. Some epidemiological associations between the cadmium level or cadmium:zinc ratio and cardiovascular disease have been reported, but are contradictory. Some epidemiological support exists for a protective effect by selenium; results for zinc are equivocal. Interactions within the human system involving calcium and selected trace elements might be very important for the cardiovascular system. Review of the epidemiological literature indicates that there may be a water factor associated with cardiovascular disease. Its effects, if any, must be very weak in comparison with the effects of known risk factors. The reported inverse relationship between mortality from cardiovascular diseases and hardness of local drinking water supplies appears to be considerably less distinctive in small regional studies. (ERB)

  4. Effect of exercise training on in vivo lipolysis in intra-abdominal adipose tissue in rats

    DEFF Research Database (Denmark)

    Enevoldsen, L H; Stallknecht, B; Fluckey, J D

    2000-01-01

    Intra-abdominal obesity is associated with cardiovascular disease and non-insulin-dependent diabetes mellitus, and physical training has been suggested to alleviate these conditions. We compared epinephrine-stimulated lipolysis in vivo in three intra-abdominal adipose tissues (ATs: retroperitoneal......, parametrial, and mesenteric) and in subcutaneous AT, and we also studied the effect of physical training. Moreover, we studied the effect of physical training on epinephrine-stimulated lipolysis in muscle in vivo. Female rats were either swim trained (15 wk, n = 8) or sedentary (n = 7). Under anesthesia......, a two-stage intravenous epinephrine infusion (60 min of 80 and 200 ng. kg(-1). min(-1), respectively) was carried out, and local interstitial glycerol concentration was measured by the microdialysis technique. Blood flow was measured by microspheres. Training increased blood flow in all ATs [on average...

  5. Biotransformation and cardiovascular effects of arachidonic acid in the dog.

    Science.gov (United States)

    Mullane, K M; Dusting, G J; Salmon, J A; Moncada, S; Vane, J R

    1979-03-01

    The biotransformation and cardiovascular effects of arachidonic acid (AA) were studied in the circulation of anaesthetized dogs. Arterial blood was continuously bioassayed for arachidonate metabolites using the blood-bathed organ technique of Vane. AA (5-10 microgram/ml) infused into an incubation coil of flowing blood was converted into a labile substance which contracted the vascular tissues (rabbit aorta, RbA; rabbit coeliac and mesenteric arteries, RbCA and RbMA; bovine coronary artery, BCA) and the gastrointestinal smooth muscle strips (rat stomach strip, RSS; rat colon, RC). These effects could be mimicked by exogenously generated thromboxane A2 (TXA2). Conversion of AA was inhibited by indomethacin and the selective thromboxane synthetase inhibitor, imidazole (100 microgram/ml). The half-life of TXA2 in blood was 30-47 sec, a similar value to that found in aqueous solutions at 37 degrees C. PGH2 was also converted in blood to other product(s) which contracted RSS and RC, relaxed RbCA and RbMA but had little effect on RbA. Intravenous infusion of AA (50-800 microgram kg-1 min-1) caused effects on the bioassay tissues which could be mimicked by prostacyclin. The AA infusion also induced falls in pulmonary and systemic arterial pressures and bradycardia. All effects were abolished by indomethacin (5 mg/kg) or aspirin (200 mg/kg). Radioimmunoassay confirmed that the major product of intravenously infused AA was 6-oxo-PGF1alpha, the chemical degradation product of prostacyclin. Thus, although AA is transformed to the vasoconstrictor TXA2 when incubated for sufficient time with blood alone, on rapid pulmonary transit it is transformed into a prostacyclin-like substance.

  6. Cardiovascular magnetic resonance in hypertrophic cardiomyopathy and infiltrative cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Rebecca Schofield

    2016-11-01

    Full Text Available Hypertrophic cardiomyopathy (HCM is the most common inherited cardiac disease. Cardiac imaging plays a key role in the diagnosis and management, with cardiovascular magnetic resonance (CMR an important modality. CMR provides a number of different techniques in one examination: structure and function, flow imaging and tissue characterisation particularly with the late gadolinium enhancement (LGE technique. Other techniques include vasodilator perfusion, mapping (especially T1 mapping and extracellular volume quantification [ECV] and diffusion-weighted imaging with its potential to detect disarray. Clinically, the uses of CMR are diverse. The imaging must be considered within the context of work-up, particularly the personal and family history, Electrocardiogram (ECG and echocardiogram findings. Subtle markers of possible HCM can be identified in genotype positive left ventricular hypertrophy (LVH-negative subjects. CMR has particular advantages for assessment of the left ventricle (LV apex and is able to detect both missed LVH (apical and basal antero-septum, when the echocardiography is normal but the ECG abnormal. CMR is important in distinguishing HCM from both common phenocopies (hypertensive heart disease, athletic adaptation, ageing related changes and rarer pheno and/or genocopies such as Fabry disease and amyloidosis. For these, in particular the LGE technique and T1 mapping are very useful with a low T1 in Fabry’s, and high T1 and very high ECV in amyloidosis. Moreover, the tissue characterisation that is possible using CMR offers a potential role in patient risk stratification, as scar is a very strong predictor of future heart failure. Scar may also play a role in the prediction of sudden death. CMR is helpful in follow-up assessment, especially after septal alcohol ablation and myomectomy.

  7. Cardiovascular: radioisotopic angiocardiography

    International Nuclear Information System (INIS)

    Kriss, J.P.

    1975-01-01

    Radioisotopic angiocardiography, performed after the intravenous injection of 99 /sup m/Tc-labeled pertechnetate or albumin, is a simple, rapid, and safe procedure which permits identification and physiologic assessment of a wide variety of congenital and acquired cardiovascular lesions in infants and children. These include atrial and ventricular septal defect, tetralogy of Fallot, pulmonic stenosis, aortopulmonary window, transposition of the great vessels, valvular stenosis and/or insufficiency, myocardial lesions, and lesions of the great vessels. The simplicity of the procedure lends itself to repeated measurements to assess the effects of therapy or to follow the course of the disease. A wide spectrum of congenital and acquired cardiovascular diseases have been studied which have particular application to the pediatric age group. (auth)

  8. Prodrugs in Cardiovascular Therapy

    Directory of Open Access Journals (Sweden)

    Maryam Tabrizian

    2008-05-01

    Full Text Available Prodrugs are biologically inactive derivatives of an active drug intended to solve certain problems of the parent drug such as toxicity, instability, minimal solubility and non-targeting capabilities. The majority of drugs for cardiovascular diseases undergo firstpass metabolism, resulting in drug inactivation and generation of toxic metabolites, which makes them appealing targets for prodrug design. Since prodrugs undergo a chemical reaction to form the parent drug once inside the body, this makes them very effective in controlling the release of a variety of compounds to the targeted site. This review will provide the reader with an insight on the latest developments of prodrugs that are available for treating a variety of cardiovascular diseases. In addition, we will focus on several drug delivery methodologies that have merged with the prodrug approach to provide enhanced target specificity and controlled drug release with minimal side effects.

  9. Cardiovascular responses to spaceflight

    Science.gov (United States)

    Nicogossian, A.; Pool, S. L.; Rambaut, P. C.

    1983-01-01

    The cardiovascular system's adaptive changes during and after spaceflight are discussed. Cephalic fluid shifts are demonstrated by photographs along with calf girth and leg volume changes. Inflight measurements show an increase in average resting heart rate and systolic blood pressure, and a sympathetic-parasympathetic neural imbalance. Postflight findings include a small but reversible decrease in the left ventricular muscle mass. Since 1980, NASA's research has emphasized cardiovascular deconditioning and countermeasures: hemodynamic changes, endocrine and neurohumoral aspects, etiologic factors, and lower body negative pressure devices. Though human beings acclimate to the space environment, questions concerning the immediate and long-term aspects of spaceflight need to be answered for adequate planning of extended space missions.

  10. Psoriasis and cardiovascular events

    DEFF Research Database (Denmark)

    Raaby, Line; Ahlehoff, Ole; de Thurah, Annette

    2017-01-01

    Register databases. In total, 13 high-quality observational studies estimating the incidence of CVD were included. Patients with mild psoriasis had an increased risk of stroke [Hazard ratio (HR) = 1.10, 95% CI: 1.0-1.19] and myocardial infarction (MI) (HR = 1.20, 95% CI: 1.06-1.35), but not cardiovascular...... death. The risks of both stroke (HR = 1.38, 95% CI: 1.20-1.60), MI (HR = 1.70, 95% CI: 1.18-2.43) and cardiovascular death (HR = 1.37, 95% CI: 1.13-1.67) were increased in patients with severe psoriasis. In conclusion, this updated meta-analysis confirmed that patients with psoriasis have an increased...... risk of CVD, especially those with severe psoriasis....

  11. Hypnotizability modulates the cardiovascular correlates of subjective relaxation.

    Science.gov (United States)

    Santarcangelo, Enrica L; Paoletti, Giulia; Balocchi, Rita; Carli, Giancarlo; Morizzo, Carmela; Palombo, Carlo; Varanini, Maurizio

    2012-01-01

    Mean values and the spectral variability of heart rate (HRV), blood pressure, and skin blood flow were studied in high and low hypnotizable subjects during simple relaxation. Similar subjective relaxation was reported by highs and lows. A parasympathetic prevalence (indicated by a higher High-Frequency component of HRV and a lower High/Low-Frequency ratio) and lower renin-angiotensin activity (indicated by a lower Very-Low-Frequency component of HRV) could be attributed to highs with respect to lows. Hypnotizability did not affect blood pressure and its variability and modulated the skin blood flow across the session only in lows. The findings confirm that relaxation cannot be defined solely on cardiovascular parameters and also indicate that hypnotizability modulates cardiovascular activity during simple relaxation and suggest it may have a protective role against cardiovascular disease.

  12. Cardiovascular Molecular Imaging

    International Nuclear Information System (INIS)

    Lee, Kyung Han

    2009-01-01

    Molecular imaging strives to visualize processes in living subjects at the molecular level. Monitoring biochemical processes at this level will allow us to directly track biological processes and signaling events that lead to pathophysiological abnormalities, and help make personalized medicine a reality by allowing evaluation of therapeutic efficacies on an individual basis. Although most molecular imaging techniques emerged from the field of oncology, they have now gradually gained acceptance by the cardiovascular community. Hence, the availability of dedicated high-resolution small animal imaging systems and specific targeting imaging probes is now enhancing our understanding of cardiovascular diseases and expediting the development of newer therapies. Examples include imaging approaches to evaluate and track the progress of recent genetic and cellular therapies for treatment of myocardial ischemia. Other areas include in vivo monitoring of such key molecular processes as angiogenesis and apoptosis. Cardiovascular molecular imaging is already an important research tool in preclinical experiments. The challenge that lies ahead is to implement these techniques into the clinics so that they may help fulfill the promise of molecular therapies and personalized medicine, as well as to resolve disappointments and controversies surrounding the field

  13. Biomaterials in myocardial tissue engineering

    Science.gov (United States)

    Reis, Lewis A.; Chiu, Loraine L. Y.; Feric, Nicole; Fu, Lara; Radisic, Milica

    2016-01-01

    Cardiovascular disease is the leading cause of death in the developed world, and as such there is a pressing need for treatment options. Cardiac tissue engineering emerged from the need to develop alternate sources and methods of replacing tissue damaged by cardiovascular diseases, as the ultimate treatment option for many who suffer from end-stage heart failure is a heart transplant. In this review we focus on biomaterial approaches to augment injured or impaired myocardium with specific emphasis on: the design criteria for these biomaterials; the types of scaffolds—composed of natural or synthetic biomaterials, or decellularized extracellular matrix—that have been used to develop cardiac patches and tissue models; methods to vascularize scaffolds and engineered tissue, and finally injectable biomaterials (hydrogels)designed for endogenous repair, exogenous repair or as bulking agents to maintain ventricular geometry post-infarct. The challenges facing the field and obstacles that must be overcome to develop truly clinically viable cardiac therapies are also discussed. PMID:25066525

  14. Applicability of implantable telemetry systems in cardiovascular research.

    Science.gov (United States)

    Krutz, R. W.; Rader, R. D.; Meehan, J. P.; Henry, J. P.

    1971-01-01

    This paper briefly describes the results of an experimental program undertaken to develop and apply implanted telemetry to cardiovascular research. Because of the role the kidney may play in essential hypertension, emphasis is placed on telemetry's applicability in the study of renal physiology. Consequently, the relationship between pressure, flow, and hydraulic impedance are stressed. Results of an exercise study are given.

  15. A study of cardiovascular and respiratory parameters in obese and ...

    African Journals Online (AJOL)

    ... heart rate, higher blood pressure, higher respiratory rate and peak expiratory flow rate among the obese subjects when compared to those of the non-obese subjects. This shows that obesity has effects on the cardio respiratory fitness of obese people. Keywords: cardiovascular parameters, respiratory parameters, obesity.

  16. Acute effects of glucagon-like peptide-1, GLP-19-36 amide, and exenatide on mesenteric blood flow, cardiovascular parameters, and biomarkers in healthy volunteers

    DEFF Research Database (Denmark)

    Hansen, Lasse Bremholm; Andersen, Ulrik B; Hornum, Mads

    2017-01-01

    arteries. GLP-1 significantly increased heart rate (two-way ANOVA, injection [P = 0.0162], time [P = 0.0038], and injection × time [P = 0.082]; Tukey post hoc GLP-1 vs. saline and GLP-19-36amide [P stroke volume compared to GLP-19-36 amide...... subcutaneous injections of GLP-1, GLP-19-36 amide (bioactive metabolite), exenatide (stable GLP-1 agonist), or saline on four separate days. Blood flow in mesenteric, celiac, and renal arteries was measured by Doppler ultrasound. Blood pressure, heart rate, cardiac output, and stroke volume were measured...

  17. [Soya isoflavones and evidences on cardiovascular protection].

    Science.gov (United States)

    González Cañete, Natalia; Durán Agüero, Samuel

    2014-06-01

    Soya isoflavones represent a group of non-nutritive, bioactive compounds, of non-steroidal phenolic nature that are present in soy bean and derived foods. They share with other compounds the capacity of binding to estrogenic receptors from different cells and tissues so that they may act as phytoestrogens. The current interest in these compounds comes from the knowledge that in Asian populations with high levels of their consumption the prevalence of cancer and cardiovascular disease is lower, as compared to the Western countries populations. This cardiovascular benefit would be the result not only of the modulation of plasma lipids, which is a widely studied mechanism. This paper reviews the published evidence about the beneficial effects of soya isoflavones and the different mechanisms of action that would benefit cardiovascular health and that surpass the mechanisms traditionally approached such as the modulation of plasma lipids, and that implicate the regulation of cellular and enzymatic functions in situations such as inflammation, thrombosis, and atherosclerotic progression. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  18. Carotenoids: potential allies of cardiovascular health?

    Directory of Open Access Journals (Sweden)

    Maria Alessandra Gammone

    2015-02-01

    Full Text Available Carotenoids are a class of natural, fat-soluble pigments found principally in plants. They have potential antioxidant biological properties because of their chemical structure and interaction with biological membranes. Epidemiologic studies supported the hypothesis that antioxidants could be used as an inexpensive means of both primary and secondary cardiovascular disease (CVD prevention. In fact, the oxidation of low-density lipoproteins (LDL in the vessels plays a key role in the development of atherosclerotic lesions. The resistance of LDL to oxidation is increased by high dietary antioxidant intake, so that carotenoids, as part of food patterns such as the Mediterranean diet, may have beneficial effects on cardiovascular health too. Further properties of carotenoids leading to a potential reduction of cardiovascular risk are represented by lowering of blood pressure, reduction of pro-inflammatory cytokines and markers of inflammation (such as C-reactive protein, and improvement of insulin sensitivity in muscle, liver, and adipose tissues. In addition, recent nutrigenomics studies have focused on the exceptional ability of carotenoids in modulating the expression of specific genes involved in cell metabolism. The aim of this review is to focus attention to this effect of some carotenoids to prevent CVD.

  19. Carotenoids: potential allies of cardiovascular health?

    Science.gov (United States)

    Gammone, Maria Alessandra; Riccioni, Graziano; D'Orazio, Nicolantonio

    2015-01-01

    Carotenoids are a class of natural, fat-soluble pigments found principally in plants. They have potential antioxidant biological properties because of their chemical structure and interaction with biological membranes. Epidemiologic studies supported the hypothesis that antioxidants could be used as an inexpensive means of both primary and secondary cardiovascular disease (CVD) prevention. In fact, the oxidation of low-density lipoproteins (LDL) in the vessels plays a key role in the development of atherosclerotic lesions. The resistance of LDL to oxidation is increased by high dietary antioxidant intake, so that carotenoids, as part of food patterns such as the Mediterranean diet, may have beneficial effects on cardiovascular health too. Further properties of carotenoids leading to a potential reduction of cardiovascular risk are represented by lowering of blood pressure, reduction of pro-inflammatory cytokines and markers of inflammation (such as C-reactive protein), and improvement of insulin sensitivity in muscle, liver, and adipose tissues. In addition, recent nutrigenomics studies have focused on the exceptional ability of carotenoids in modulating the expression of specific genes involved in cell metabolism. The aim of this review is to focus attention to this effect of some carotenoids to prevent CVD. PMID:25660385

  20. Pro-resolution therapeutics for cardiovascular diseases.

    Science.gov (United States)

    Heinz, Justin; Marinello, Michael; Fredman, Gabrielle

    2017-09-01

    Studies over the last couple of decades suggest that failed resolution of a chronic inflammatory response is an important driving force in the progression of atherosclerosis. Resolution of inflammation is mediated in part by lipid-derived specialized pro-resolving mediators (SPMs) such as lipoxins, resolvins, protectins and maresins. The major functions of SPMs are to quell inflammation and repair tissue damage in a manner that does not compromise host defense. An imbalance between SPMs and pro-inflammatory mediators like leukotriene B 4 (LTB 4 ) are associated with several prevalent human diseases, including atherosclerosis. Because atherosclerosis is marked by persistent, unresolved inflammation and arterial tissue injury, SPMs have garnered immense interest as a potential treatment strategy. This mini review will highlight recent advances in the application of SPMs in atherosclerosis as well as the ability of SPMs to control several of the risk factors associated with cardiovascular diseases. Copyright © 2017. Published by Elsevier Inc.

  1. Flow Rounding

    OpenAIRE

    Kang, Donggu; Payor, James

    2015-01-01

    We consider flow rounding: finding an integral flow from a fractional flow. Costed flow rounding asks that we find an integral flow with no worse cost. Randomized flow rounding requires we randomly find an integral flow such that the expected flow along each edge matches the fractional flow. Both problems are reduced to cycle canceling, for which we develop an $O(m \\log(n^2/m))$ algorithm.

  2. Tissue Classification

    DEFF Research Database (Denmark)

    Van Leemput, Koen; Puonti, Oula

    2015-01-01

    Computational methods for automatically segmenting magnetic resonance images of the brain have seen tremendous advances in recent years. So-called tissue classification techniques, aimed at extracting the three main brain tissue classes (white matter, gray matter, and cerebrospinal fluid), are now...... well established. In their simplest form, these methods classify voxels independently based on their intensity alone, although much more sophisticated models are typically used in practice. This article aims to give an overview of often-used computational techniques for brain tissue classification....... Although other methods exist, we concentrate on Bayesian modeling approaches, in which generative image models are constructed and subsequently ‘inverted’ to obtain automated segmentations. This general framework encompasses a large number of segmentation methods, including those implemented in widely used...

  3. Tissue Classification

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, David Gerald [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    The project began as a e ort to support InLight and Lumidigm. With the sale of the companies to a non-New Mexico entity, the project then focused on supporting a new company Medici Technologies. The Small Business (SB) is attempting to quantify glucose in tissue using a series of short interferometer scans of the nger. Each scan is produced from a novel presentation of the nger to the device. The intent of the project is to identify and, if possible, implement improved methods for classi cation, feature selection, and training to improve the performance of predictive algorithms used for tissue classi cation.

  4. Insulin resistance: an additional risk factor in the pathogenesis of cardiovascular disease in type 2 diabetes.

    Science.gov (United States)

    Patel, Tushar P; Rawal, Komal; Bagchi, Ashim K; Akolkar, Gauri; Bernardes, Nathalia; Dias, Danielle da Silva; Gupta, Sarita; Singal, Pawan K

    2016-01-01

    Sedentary life style and high calorie dietary habits are prominent leading cause of metabolic syndrome in modern world. Obesity plays a central role in occurrence of various diseases like hyperinsulinemia, hyperglycemia and hyperlipidemia, which lead to insulin resistance and metabolic derangements like cardiovascular diseases (CVDs) mediated by oxidative stress. The mortality rate due to CVDs is on the rise in developing countries. Insulin resistance (IR) leads to micro or macro angiopathy, peripheral arterial dysfunction, hampered blood flow, hypertension, as well as the cardiomyocyte and the endothelial cell dysfunctions, thus increasing risk factors for coronary artery blockage, stroke and heart failure suggesting that there is a strong association between IR and CVDs. The plausible linkages between these two pathophysiological conditions are altered levels of insulin signaling proteins such as IR-β, IRS-1, PI3K, Akt, Glut4 and PGC-1α that hamper insulin-mediated glucose uptake as well as other functions of insulin in the cardiomyocytes and the endothelial cells of the heart. Reduced AMPK, PFK-2 and elevated levels of NADP(H)-dependent oxidases produced by activated M1 macrophages of the adipose tissue and elevated levels of circulating angiotensin are also cause of CVD in diabetes mellitus condition. Insulin sensitizers, angiotensin blockers, superoxide scavengers are used as therapeutics in the amelioration of CVD. It evidently becomes important to unravel the mechanisms of the association between IR and CVDs in order to formulate novel efficient drugs to treat patients suffering from insulin resistance-mediated cardiovascular diseases. The possible associations between insulin resistance and cardiovascular diseases are reviewed here.

  5. Cardiovascular regulation during water immersion.

    Science.gov (United States)

    Park, K S; Choi, J K; Park, Y S

    1999-11-01

    Head-out water immersion at thermoneutral temperature (34-35 degrees C) increases cardiac output for a given O2 consumption, leading to a relative hyperperfusion of peripheral tissues. To determine if subjects immersed in water at a colder temperature show similar responses and to explore the significance of the hyperperfusion, cardiovascular functions were investigated (impedance cardiography) on 10 men at rest and while performing exercise on a leg cycle ergometer (delta M = approximately 95 W.m-2) in air and in water at 34.5 degrees C and 30 degrees C, respectively. In subjects resting in water, the cardiac output increased by approximately 50% compared to that in air, mainly due to a rise in stroke volume. The stroke volume change tended to be greater in 30 degrees C water than in 34.5 degrees C water, and this was due to a greater increase in cardiac preload, as indicated by a significantly greater left ventricular end-diastolic volume. Arterial systolic pressure rose slightly during water immersion. Arterial diastolic pressure remained unchanged in 34.5 degrees C water, but it rose in 30 degrees C water. The total peripheral resistance fell 37% in 34.5 degrees C water and 32% in 30 degrees C water. Both in air and in water, mild exercise increased the cardiac output, and this was mainly due to an increase in heart rate. Since, however, the stroke volume increased with water immersion, cardiac output at a given work load appeared to be significantly higher in water than in air. The arterial pressures did not decrease with water immersion, despite a marked reduction in total peripheral resistance. These results suggest that 1) during cold water immersion, peripheral vasoconstriction provides an additional increase in cardiac preload, leading to a further increase in the stroke volume compared to that of the thermoneutral water immersion, 2) the mechanism of cardiovascular adjustment during dynamic exercise is not changed by the persistent increase in cardiac

  6. The Cardiovascular Effects of Cocaine.

    Science.gov (United States)

    Havakuk, Ofer; Rezkalla, Shereif H; Kloner, Robert A

    2017-07-04

    Cocaine is the leading cause for drug-abuse-related visits to emergency departments, most of which are due to cardiovascular complaints. Through its diverse pathophysiological mechanisms, cocaine exerts various adverse effects on the cardiovascular system, many times with grave results. Described here are the varied cardiovascular effects of cocaine, areas of controversy, and therapeutic options. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  7. Precision Medicine in Cardiovascular Diseases

    OpenAIRE

    Yan Liu; Jie Du

    2017-01-01

    Since President Obama announced the Precision Medicine Initiative in the United States, more and more attention has been paid to precision medicine. However, clinicians have already used it to treat conditions such as cancer. Many cardiovascular diseases have a familial presentation, and genetic variants are associated with the prevention, diagnosis, and treatment of cardiovascular diseases, which are the basis for providing precise care to patients with cardiovascular diseases. Large-scale c...

  8. Diabetic Cardiovascular Disease Induced by Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Yosuke Kayama

    2015-10-01

    Full Text Available Cardiovascular disease (CVD is the leading cause of morbidity and mortality among patients with diabetes mellitus (DM. DM can lead to multiple cardiovascular complications, including coronary artery disease (CAD, cardiac hypertrophy, and heart failure (HF. HF represents one of the most common causes of death in patients with DM and results from DM-induced CAD and diabetic cardiomyopathy. Oxidative stress is closely associated with the pathogenesis of DM and results from overproduction of reactive oxygen species (ROS. ROS overproduction is associated with hyperglycemia and metabolic disorders, such as impaired antioxidant function in conjunction with impaired antioxidant activity. Long-term exposure to oxidative stress in DM induces chronic inflammation and fibrosis in a range of tissues, leading to formation and progression of disease states in these tissues. Indeed, markers for oxidative stress are overexpressed in patients with DM, suggesting that increased ROS may be primarily responsible for the development of diabetic complications. Therefore, an understanding of the pathophysiological mechanisms mediated by oxidative stress is crucial to the prevention and treatment of diabetes-induced CVD. The current review focuses on the relationship between diabetes-induced CVD and oxidative stress, while highlighting the latest insights into this relationship from findings on diabetic heart and vascular disease.

  9. NMR imaging of the cardiovascular system

    International Nuclear Information System (INIS)

    Canby, R.C.; Evanochko, W.T.; Pohost, G.M.

    1986-01-01

    Proton nuclear magnetic resonance (NMR) imaging permits high-resolution tomographic and three-dimensional images of the human body to be obtained without exposure to ionizing radiation. Such imaging not only yields anatomic resolution comparable to X-ray examinations but also provides a potential means to discriminate between healthy tissue and diseased tissue. This potential is based on certain NMR properties known as relaxation times, which determine, in part, the signal intensity in an image. These properties are related to such factors as the sizes and concentrations of proteins and mobile lipids and the compartmentalization of the protons of water. Although NMR imaging (also called magnetic resonance imaging, MRI) is becoming widely available for clinical use, application to the cardiovascular system, though promising, remains primarily a research tool. Gated proton NMR imaging can generate cardiac images with excellent morphologic detail and contrast; however, its ultimate importance as a cardiovascular diagnostic modality will depend on the development of several unique applications. These applications are discussed in this paper

  10. Precision Medicine in Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2017-02-01

    Full Text Available Since President Obama announced the Precision Medicine Initiative in the United States, more and more attention has been paid to precision medicine. However, clinicians have already used it to treat conditions such as cancer. Many cardiovascular diseases have a familial presentation, and genetic variants are associated with the prevention, diagnosis, and treatment of cardiovascular diseases, which are the basis for providing precise care to patients with cardiovascular diseases. Large-scale cohorts and multiomics are critical components of precision medicine. Here we summarize the application of precision medicine to cardiovascular diseases based on cohort and omic studies, and hope to elicit discussion about future health care.

  11. Connective tissue diseases and noninvasive evaluation of atherosclerosis

    Directory of Open Access Journals (Sweden)

    Ardita G

    2014-06-01

    Full Text Available Giorgio Ardita, Giacomo Failla, Paolo Maria Finocchiaro, Francesco Mugno, Luigi Attanasio, Salvatore Timineri, Michelangelo Maria Di SalvoCardiovascular Department, Angiology Unit, Ferrarotto Hospital, Catania, ItalyAbstract: Connective tissue diseases (CTDs are associated with increased risk of cardiovascular disease due to accelerated atherosclerosis. In patients with autoimmune disorders, in addition to traditional risk factors, an immune-mediated inflammatory process of the vasculature seems to contribute to atherogenesis. Several pathogenetic mechanisms have been proposed, including chronic inflammation and immunologic abnormalities, both able to produce vascular damage. Macrovascular atherosclerosis can be noninvasively evaluated by ultrasound measurement of carotid or femoral plaque. Subclinical atherosclerosis can be evaluated by well-established noninvasive techniques which rely on ultrasound detection of carotid intima-media thickness. Flow-mediated vasodilatation and arterial stiffness are considered markers of endothelial dysfunction and subclinical atherosclerosis, respectively, and have been recently found to be impaired early in a wide spectrum of autoimmune diseases. Carotid intima-media thickness turns out to be a leading marker of subclinical atherosclerosis, and many studies recognize its role as a predictor of future vascular events, both in non-CTD individuals and in CTD patients. In rheumatic diseases, flow-mediated dilatation and arterial stiffness prove to be strongly correlated with inflammation, disease damage index, and with subclinical atherosclerosis, although their prognostic role has not yet been conclusively shown. Systemic lupus erythematosus, rheumatoid arthritis, and likely antiphospholipid syndrome are better associated with premature and accelerated atherosclerosis. Inconclusive results were reported in systemic sclerosis.Keywords: rheumatic disease, subclinical atherosclerosis, arterial stiffness

  12. Cardiovascular Complications of Pregnancy

    Science.gov (United States)

    Gongora, Maria Carolina; Wenger, Nanette K.

    2015-01-01

    Pregnancy causes significant metabolic and hemodynamic changes in a woman’s physiology to allow for fetal growth. The inability to adapt to these changes might result in the development of hypertensive disorders of pregnancy (hypertension, preeclampsia or eclampsia), gestational diabetes and preterm birth. Contrary to previous beliefs these complications are not limited to the pregnancy period and may leave permanent vascular and metabolic damage. There is in addition, a direct association between these disorders and increased risk of future cardiovascular disease (CVD, including hypertension, ischemic heart disease, heart failure and stroke) and diabetes mellitus. Despite abundant evidence of this association, women who present with these complications of pregnancy do not receive adequate postpartum follow up and counseling regarding their increased risk of future CVD. The postpartum period in these women represents a unique opportunity to intervene with lifestyle modifications designed to reduce the development of premature cardiovascular complications. In some cases it allows early diagnosis and treatment of chronic hypertension or diabetes mellitus. The awareness of this relationship is growing in the medical community, especially among obstetricians and primary care physicians, who play a pivotal role in detecting these complications and assuring appropriate follow up. PMID:26473833

  13. Genomics and cardiovascular disease.

    Science.gov (United States)

    Frazier, Lorraine; Johnson, Rolanda L; Sparks, Elizabeth

    2005-01-01

    To describe genetic knowledge and discovery in the area of cardiovascular disease (CVD) and to discuss how these new advances will influence the clinical care of affected people. A selective review of the literature is presented on the disease mechanism of both the Mendelian and multifactorial genetic cardiovascular conditions. A case study approach is used to illustrate how the genetic paradigm affects the healthcare experience of a family affected with familial hypertrophic cardiomyopathy. The current state of CVD treatment remains complex. An understanding of genomic concepts and a genome-based approach is necessary to determine: (a) the risk of CVD susceptibility beyond traditional risk factors; (b) early detection of illness; (c) response to treatment; and (d) molecular taxonomy of the disease. The results of genetic research, education, and teaching will lead to a new understanding of genes and pathways, resulting in powerful new therapeutic approaches to CVD. The challenge is to translate genetic discoveries into clinical practice that ultimately leads to preventing CVD and reducing mortality.

  14. Cardiovascular Implications of Preeclampsia.

    Science.gov (United States)

    Burgess, Adriane; Founds, Sandra

    2016-01-01

    Cardiovascular disease (CVD) is the leading cause of death of women in the United States. Many healthcare providers are unaware of sex-specific factors that affect the development of CVD. Nursing care for women with a history of preeclampsia and their children is presented. Preeclampsia affects 4% to 8% of all pregnancies. Rates have increased by 25% over the past 2 decades. Research supports the link between preeclampsia and risk of future CVD in women and the children of affected pregnancies. Appropriate preconception, prenatal and postpartum education, and surveillance are necessary to improve the long-term health of both mother and infant. Currently, there are no evidence-based interventions specific to the prevention of CVD for women and their children who have been affected by preeclampsia. However, women who have had preeclampsia may require yearly risk factor assessment and education regarding cardiovascular prevention strategies such as smoking cessation, increased physical activity, importance of a healthy diet, and maintenance of a healthy weight. Preeclampsia should be acknowledged by healthcare providers as a CVD risk factor. Appropriate monitoring, education, and CVD preventive strategies need to be implemented with this population and their children.

  15. Cardiovascular benefits of exercise

    Directory of Open Access Journals (Sweden)

    Agarwal SK

    2012-06-01

    Full Text Available Shashi K AgarwalMedical Director, Agarwal Health Center, NJ, USAAbstract: Regular physical activity during leisure time has been shown to be associated with better health outcomes. The American Heart Association, the Centers for Disease Control and Prevention and the American College of Sports Medicine all recommend regular physical activity of moderate intensity for the prevention and complementary treatment of several diseases. The therapeutic role of exercise in maintaining good health and treating diseases is not new. The benefits of physical activity date back to Susruta, a 600 BC physician in India, who prescribed exercise to patients. Hippocrates (460–377 BC wrote “in order to remain healthy, the entire day should be devoted exclusively to ways and means of increasing one's strength and staying healthy, and the best way to do so is through physical exercise.” Plato (427–347 BC referred to medicine as a sister art to physical exercise while the noted ancient Greek physician Galen (129–217 AD penned several essays on aerobic fitness and strengthening muscles. This article briefly reviews the beneficial effects of physical activity on cardiovascular diseases.Keywords: exercise, cardiovascular disease, lifestyle changes, physical activity, good health

  16. [Cardiovascular aspects of vertigo].

    Science.gov (United States)

    Verbeet, Th

    2002-09-01

    True vertigo described as a sensation of body or surrounding objects rotation is seldom of cardiovascular origin. The main causes are caused by ear pathology, neurologic pathology or are of toxic origin. Patients talk frequently of vertigo to describe symptoms in relation with a fall of the brain blood output. These dizziness feelings are frequently of cardiovascular origin and may be associated with syncope which represents a more important fall in the brain blood pressure. Medical history, physical examination, electrocardiogram represents the cornerstones of the cardiological workout allowing about 50% of likely diagnosis. The cardiologist will also have to distinguish between a disease of benign prognosis and a disease possibly associated with future sudden cardiac death. The main cardiological causes are: neurally mediated hypotension, orthostatic hypotension, cardiac arrhythmias, other cardiac or pulmonary diseases. Neurological, metabolic or psychiatric causes occur much less frequently. Most commonly used diagnostic tests include the resting electrocardiogram, the stress test, cardiac echography, holter techniques, tilt testing, cardiac and coronary angiography, electrophysiologic testing. However, despite an extensive workout some causes of dizziness or syncope remain unclear.

  17. Nicotine and periodontal tissues

    Directory of Open Access Journals (Sweden)

    Malhotra Ranjan

    2010-01-01

    Full Text Available Tobacco use has been recognized to be a significant risk factor for the development and progression of periodontal disease. Its use is associated with increased pocket depths, loss of periodontal attachment, alveolar bone and a higher rate of tooth loss. Nicotine, a major component and most pharmacologically active agent in tobacco is likely to be a significant contributing factor for the exacerbation of periodontal diseases. Available literature suggests that nicotine affects gingival blood flow, cytokine production, neutrophil and other immune cell function; connective tissue turnover, which can be the possible mechanisms responsible for overall effects of tobacco on periodontal tissues. Inclusion of tobacco cessation as a part of periodontal therapy encourages dental professionals to become more active in tobacco cessation counseling. This will have far reaching positive effects on our patients′ oral and general health.

  18. Cardiovascular risk in rheumatoid arthritis.

    Science.gov (United States)

    Soubrier, Martin; Barber Chamoux, Nicolas; Tatar, Zuzana; Couderc, Marion; Dubost, Jean-Jacques; Mathieu, Sylvain

    2014-07-01

    The objectives of this review are to discuss data on the cardiovascular risk increase associated with rheumatoid arthritis (RA), the effects of RA treatments on the cardiovascular risk level, and the management of cardiovascular risk factors in patients with RA. Overall, the risk of cardiovascular disease is increased 2-fold in RA patients compared to the general population, due to the combined effects of RA and conventional risk factors. There is some evidence that the cardiovascular risk increase associated with nonsteroidal anti-inflammatory drug therapy may be smaller in RA patients than in the general population. Glucocorticoid therapy increases the cardiovascular risk in proportion to both the current dose and the cumulative dose. Methotrexate and TNFα antagonists diminish cardiovascular morbidity and mortality rates. The management of dyslipidemia remains suboptimal. Risk equations may perform poorly in RA patients even when corrected using the multiplication factors suggested by the EUropean League Against Rheumatism (EULAR) (multiply the score by 1.5 when two of the following three criteria are met: disease duration longer than 10 years, presence of rheumatoid factor or anti-cyclic citrullinated peptide (CCP) antibodies, and extraarticular manifestations). Doppler ultrasonography of the carotid arteries in patients at moderate cardiovascular risk may allow a more aggressive approach to dyslipidemia management via reclassification into the high-risk category of patients with an intima-media thickness greater than 0.9 mm or atheroma plaque. Copyright © 2014. Published by Elsevier SAS.

  19. Cheese and cardiovascular disease risk

    DEFF Research Database (Denmark)

    Hjerpsted, Julie Bousgaard; Tholstrup, Tine

    2016-01-01

    Abstract Currently, the effect of dairy products on cardiovascular risk is a topic with much debate and conflicting results. The purpose of this review is to give an overview of the existing literature regarding the effect of cheese intake and risk of cardiovascular disease (CVD). Studies included...

  20. Educational differences in cardiovascular mortality

    DEFF Research Database (Denmark)

    Kjøllesdal, M. K. R.; Ariansen, I.; Mortensen, L. H.

    2016-01-01

    Aims: To explore the confounding effects of early family factors shared by siblings and cardiovascular risk factors in midlife on the educational differences in mortality from cardiovascular disease (CVD). Methods: Data from national and regional health surveys in Norway (1974–2003) were linked...

  1. Modeling of hyaluronan clearance with application to estimation of lymph flow

    International Nuclear Information System (INIS)

    Rössler, Andreas; Goswami, Nandu; Fink, Martin; Batzel, Jerry J

    2011-01-01

    One of the important factors in blood pressure regulation is the maintenance of the level of blood volume, which depends on several factors including the rate of lymph flow. Lymph flow can be measured directly using cannulation of lymphatic vessels, which is not clinically feasible, or indirectly by the tracer appearance rate, which is the rate at which macromolecules appear into the blood from the peritoneal cavity. However, indirect lymph flow measurements do not always provide consistent results. Through its contribution to osmotic pressure and resistance to flow, the macromolecule hyaluronan takes part in the regulation of tissue hydration and the maintenance of water and protein homeostasis. It arrives in blood plasma through lymph flow. Lymphatic hyaluronic acid (HA, hyaluronan) concentration is several times higher than that in plasma, suggesting that the lymphatic route may account for the majority of HA found in plasma. Furthermore, circulating levels of HA reflect the dynamic state between delivery to—and removal from—the bloodstream. To develop an accurate estimation of the fluid volume distribution and dynamics, the rate of lymph flow needs to be taken into account and hyaluronan could be used as a marker in estimating this flow. To examine the HA distribution and system fluid dynamics, a six-compartment model, which could reflect both the steady-state relationships and qualitative characteristics of the dynamics, was developed. This was then applied to estimate fluid shifts from the interstitial space via the lymphatic system to the plasma during different physiological stresses (orthostatic stress and the stress of ultrafiltration during dialysis). Sensitivity analysis shows that during ultrafiltration, lymph flow is a key parameter influencing the total HA level, thus suggesting that the model may find applications in addressing the problem of estimating lymph flow. Since the fluid balance between interstitium and plasma is maintained by lymph

  2. Flow structures in cerebral aneurysms

    OpenAIRE

    Gambaruto, Alberto M; João, Ana

    2012-01-01

    Mechanical properties of blood flow are commonly correlated to a wide range of cardiovascular diseases. In this work means to describe and characterise the flow field in the free-slip and no-slip domains are discussed in the context of cerebral aneurysms, reconstructed from in-vivo medical imaging. The approaches rely on a Taylor series expansion of the velocity field to first order terms that leads to a system of ODEs, the solution to which locally describes the motion of the flow. On perfor...

  3. RIA in cardiovascular disease

    International Nuclear Information System (INIS)

    Hourani, M.H.

    1983-01-01

    When one discusses the management of chronic cardiac diseases, and in particular congestive heart failure (CHF), one cannot but think of digitalis and the important role it plays in the management of CHF. One also has to think about digitalis toxicity and the narrow margin between the therapeutic and toxic doses of digitalis and the important role that monitoring the serum level of the drug play in preventing and/or recognizing its toxic effects. Again, RIA has something to offer the clinician in this area. The purpose of this chapter is to discuss the radioassays for CPK-MB and digoxin mainly, as well as touch upon other assays of use in evaluating patients with cardiovascular disease

  4. Cardiovascular diseases and diabetes

    DEFF Research Database (Denmark)

    Green, A.; Sortso, C.; Jensen, Peter Bjødstrup

    2016-01-01

    We present an investigation of the occurrence of cardiovascular disease in patients with diabetes in Denmark 2000 through 2011. The Diabetes Impact Study 2013 is based on all registrants in the Danish National Diabetes Register as of July 3rd 2013 (n=497,232). Record linkage with the Danish...... of diabetes has been rather constant at higher level in males (around 16-18%) than in females (around 12-14%) during 2000-2011 (incl.). In contrast, the incidence rate of CVD after having diabetes diagnosis has declined from about 4.5 to less than 3 during the same period, with higher declining level...... for males than for females. Efforts to detect diabetes at an earlier stage have not resulted in a reduced occurrence of CVD at the diagnosis of diabetes in Denmark. However, the risk of developing CVD after the diagnosis of diabetes has been declining, possibly reflecting benefits of intensified treatment...

  5. Assessment of cardiovascular risk.

    LENUS (Irish Health Repository)

    Cooney, Marie Therese

    2010-10-01

    Atherosclerotic cardiovascular disease (CVD) is the most common cause of death worldwide. Usually atherosclerosis is caused by the combined effects of multiple risk factors. For this reason, most guidelines on the prevention of CVD stress the assessment of total CVD risk. The most intensive risk factor modification can then be directed towards the individuals who will derive the greatest benefit. To assist the clinician in calculating the effects of these multiple interacting risk factors, a number of risk estimation systems have been developed. This review address several issues regarding total CVD risk assessment: Why should total CVD risk be assessed? What risk estimation systems are available? How well do these systems estimate risk? What are the advantages and disadvantages of the current systems? What are the current limitations of risk estimation systems and how can they be resolved? What new developments have occurred in CVD risk estimation?

  6. Risk of cardiovascular disease

    DEFF Research Database (Denmark)

    Gejl, Michael; Starup-Linde, Jakob; Scheel-Thomsen, Jan

    2014-01-01

    AIMS: Type 2 diabetes (DM) increases the risk of cardiovascular disease. We investigated the effects of antidiabetic drugs on the composite endpoint (CE) of ischemic heart disease, heart failure or stroke in DM patients. METHODS: We conducted a nested case-control study. Cases were DM patients who......% CI: 16.88-24.12), neuropathy (OR=1.39, 95% CI: 1.05-1.85) and peripheral artery disease (OR=1.31, 95% CI: 1.02-1.69) increased the risk of CE. Biguanides (OR=0.62 95% CI; 0.54-0.71) and liraglutide (OR=0.48 95% CI; 0.38-0.62) significantly decreased the risk of CE as did statin treatment (OR=0.63, 95...

  7. Cardiovascular hospitalizations and associations with environmental quality

    Science.gov (United States)

    Cardiovascular disease has been identified as a condition that may be associated with environmental factors. Air pollution in particular has been demonstrated to be associated with cardiovascular disease and atherosclerosis, which can increase the likelihood of cardiovascular eve...

  8. Cardiovascular effects of basal insulins

    Directory of Open Access Journals (Sweden)

    Mannucci E

    2015-07-01

    Full Text Available Edoardo Mannucci,1 Stefano Giannini,2 Ilaria Dicembrini1 1Diabetes Agency, Careggi Teaching Hospital, Florence, 2Section of Endocrinology, Department of Biomedical Clinical and Experimental Sciences, University of Florence and Careggi University Hospital, Florence, Italy Abstract: Basal insulin is an important component of treatment for both type 1 and type 2 diabetes. One of the principal aims of treatment in patients with diabetes is the prevention of diabetic complications, including cardiovascular disease. There is some evidence, although controversial, that attainment of good glycemic control reduces long-term cardiovascular risk in both type 1 and type 2 diabetes. The aim of this review is to provide an overview of the potential cardiovascular safety of the different available preparations of basal insulin. Current basal insulin (neutral protamine Hagedorn [NPH], or isophane and basal insulin analogs (glargine, detemir, and the more recent degludec differ essentially by various measures of pharmacokinetic and pharmacodynamic effects in the bloodstream, presence and persistence of peak action, and within-subject variability in the glucose-lowering response. The currently available data show that basal insulin analogs have a lower risk of hypoglycemia than NPH human insulin, in both type 1 and type 2 diabetes, then excluding additional harmful effects on the cardiovascular system mediated by activation of the adrenergic system. Given that no biological rationale for a possible difference in cardiovascular effect of basal insulins has been proposed so far, available meta-analyses of publicly disclosed randomized controlled trials do not show any signal of increased risk of major cardiovascular events between the different basal insulin analogs. However, the number of available cardiovascular events in these trials is very small, preventing any clear-cut conclusion. The results of an ongoing clinical trial comparing glargine and degludec with

  9. Advanced Cardiovascular Monitoring

    NARCIS (Netherlands)

    de Waal, E.E.C.

    2009-01-01

    The Frank-Starling curve (the curvilinear relation between cardiac output (CO) and preload) can be used for optimalization of the blood circulation and tissue oxygenation, in order to decrease morbidity and mortality in high risk surgery and critically ill patients. Measurement of CO and preload

  10. [Brief lecture on cardiovascular biomarkers based on the pathophysiology].

    Science.gov (United States)

    Shimada, Toshio

    2011-10-01

    Living organisms on the earth live dependent on the sun. Human beings are unexceptional. Plants with chlorophyll on the earth capture energy radiated from the sun and produce carbohydrate and oxygen from carbon dioxide and water using the energy from the sun. Herbivorous animals eat plants, carnivorous ones eat herbivorous ones and human beings eat both with a small amount of vitamins and minerals. Food including carbohydrate, protein and lipid which is digested by the gastroenteric system and mainly absorbed through the small intestine. Finally, nutrients from the digestive system and oxygen from the lungs are brought to the cells or the tissue through the cardiovascular system. Acetyl-CoA from food and oxygen from the lungs are chemically burned in the mitochondria to produce a lot of ATP. On the way of ATP production, unfavorable free radicals are inevitably produced to result in cancer and/or atherosclerosis. Cardiovascular system delivers oxygen and nutrients to the tissue or the cells. Literally, it is a pipe line for life support and then we must maintain cardiovascular system well to live long in good health. And therefore, it is essential to find cardiovascular abnormality as early as possible. Cardiovascular biomarkers such as BNP and NT-proBNP for screening for heart failure, RemL-C for screening for metabolic syndrome, cystatin C for screening for renal impairment and high sensitive troponin I, T for screening for ischemic myocardial damage have been greatly expected as tools to find early cardiovascular disorders for long survival in health examination and clinical practice.

  11. The Cardiovascular Function Profile and Physical Fitness in Overweight Subjects

    Science.gov (United States)

    Megawati, E. R.; Lubis, L. D.; Harahap, F. Y.

    2017-03-01

    Obesity in children and young adult is associated with cardiovascular risk in short term and long term. The aim of this study was to describe the profile of the cardiovascular functions parameters and physical fitness in overweight. This is an analytical observational study with cross sectional approach. The samples of this study were 85 randomly selected subjects aged 18 to 24 years with normoweight and body mass index <40. The parameters measures were body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), cardiovascular function parameters (resting pulse, blood pressure, and peak flow meter) and physical fitness parameters (VO2max dengan McArdle step test). The mean BMI was 24,53±4,929. The WC and WHR mean were 86,7±14,10 cms and 0,89±0,073 cm respectively. The mean of resting pulses were higher in normoweight subject (p=0,0209). The mean systole were lower in normoweight subject (p=0,0026). No differences VO2 max between groups (p=0,3888). The peak flow meter was higher in normoweight (p=0,0274). The result of this study indicate that heart rate, systole and peak flow meter are signifantly different between groups. The heart rate and the peak flow meter in the overweight subjects were lower meanwhile the systole blood pressure was higher compared to normoweight subjects.

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

    Science.gov (United States)

    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 ...

  13. Oscillatory and electrohydrodynamic instabilities in flow over a ...

    Indian Academy of Sciences (India)

    is encountered in the flow of cardiovascular fluids through flexible blood vessels which are driven by the pumping of the heart. The Reynolds numbers for these flows vary over a wide range between Re < 1 and Re = 4000 (Ku 1997). The oscillatory nature of the blood flow in the vascular system is characterized by a number ...

  14. Leptin, obesity and cardiovascular disease.

    Science.gov (United States)

    Correia, Marcelo Lima de Gusmao; Haynes, William Geoffrey

    2004-03-01

    Obesity is a risk factor for cardiovascular diseases. Leptin levels are increased in obesity and leptin exhibits cardiovascular actions that may contribute to increased cardiovascular risk. We review the sympathetic, renal and vascular actions of leptin and their relevance to cardiovascular disease. Leptin possesses cardio-renal actions potentially contributing to obesity-related hypertension including generalized sympathoactivation. However, given that leptin resistance occurs in obesity, it has been difficult to link hyperleptinemia with hypertension. One possibility is that leptin resistance is confined to the metabolic effects of leptin, with preservation of its sympathoexcitatory actions. Other mechanisms may contribute to the pressor effects of leptin. For instance, angiotensin II induces leptin generation. Leptin also potentiates the pressor effect of insulin. Therefore, interactions between angiotensin II and insulin with leptin could have deleterious cardiovascular effects in obesity. Additionally, leptin appears to stimulate vascular inflammation, oxidative stress and hypertophy. These actions may contribute to the pathogenesis of hypertension, atherosclerosis, and left ventricular hypertrophy. The potential actions of leptin in the pathophysiology of cardiovascular complications of obesity are diverse, despite evidence of leptin resistance to its metabolic actions. However, most information about cardiovascular actions of leptin derives from in-vitro and animal studies. Future research in humans is widely awaited.

  15. Nrf2 and Cardiovascular Defense

    Directory of Open Access Journals (Sweden)

    Reuben Howden

    2013-01-01

    Full Text Available The cardiovascular system is susceptible to a group of diseases that are responsible for a larger proportion of morbidity and mortality than any other disease. Many cardiovascular diseases are associated with a failure of defenses against oxidative stress-induced cellular damage and/or death, leading to organ dysfunction. The pleiotropic transcription factor, nuclear factor-erythroid (NF-E 2-related factor 2 (Nrf2, regulates the expression of antioxidant enzymes and proteins through the antioxidant response element. Nrf2 is an important component in antioxidant defenses in cardiovascular diseases such as atherosclerosis, hypertension, and heart failure. Nrf2 is also involved in protection against oxidant stress during the processes of ischemia-reperfusion injury and aging. However, evidence suggests that Nrf2 activity does not always lead to a positive outcome and may accelerate the pathogenesis of some cardiovascular diseases (e.g., atherosclerosis. The precise conditions under which Nrf2 acts to attenuate or stimulate cardiovascular disease processes are unclear. Further studies on the cellular environments related to cardiovascular diseases that influence Nrf2 pathways are required before Nrf2 can be considered a therapeutic target for the treatment of cardiovascular diseases.

  16. Tissue irradiator

    International Nuclear Information System (INIS)

    Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

    1975-01-01

    A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in-vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood-carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170

  17. Role of peroxynitrite in the cardiovascular dysfunction of septic shock.

    Science.gov (United States)

    Liaudet, Lucas; Rosenblatt-Velin, Nathalie; Pacher, Pal

    2013-03-01

    The intense systemic inflammatory response characterizing septic shock is associated with an increased generation of free radicals by multiple cell types in cardiovascular and non cardiovascular tissues. The oxygen-centered radical superoxide anion (O2 .-) rapidly reacts with the nitrogen-centered radical nitric oxide (NO.) to form the potent oxidant species peroxynitrite. Peroxynitrite oxidizes multiple targets molecules, either directly or via the secondary generation of highly reactive radicals, resulting in significant alterations in lipids, proteins and nucleic acids, with significant cytotoxic consequences. The formation of peroxynitrite is a key pathophysiological mechanism contributing to the cardiovascular collapse of septic shock, promoting vascular contractile failure, endothelial and myocardial dysfunction, and is also implicated in the occurrence of multiple organ dysfunction in this setting. The recent development of various porphyrin-based pharmacological compounds accelerating the degradation of peroxynitrite has allowed to specifically address these pathophysiological roles of peroxynitrite in experimental septic shock. Such agents, including 5,10,15,20-tetrakis(4- sulfonatophenyl)porphyrinato iron III chloride (FeTTPs), manganese tetrakis(4-N-methylpyridyl)porphyrin (MnTMPyP), Fe(III) tetrakis-2-(N-triethylene glycol monomethyl ether)pyridyl porphyrin) (FP-15) and WW-85, have been shown to improve the cardiovascular and multiple organ failure in small and large animal models of septic shock. Therefore, these findings support the development of peroxynitrite decomposition catalysts as potentially useful novel therapeutic agents to restore cardiovascular function in sepsis.

  18. MARCADORES CARDIACOS Y RIESGO CARDIOVASCULAR

    OpenAIRE

    Dr. David Doron R.; Dr. Marcelo Muñoz C.

    2015-01-01

    La identificación del riesgo que un individuo o una población tienen de presentar un evento cardiovascular y la posibilidad de intervenir oportunamente para evitarlo, constituye el fundamento que ha propiciado la investigación de marcadores cardiacos y su potencial de predicción de riesgo cardiovascular. La mortalidad por causa cardiovascular es la primera causa de muerte en el mundo desarrollado y tambièc)n en Chile, por lo que los esfuerzos de identificación acuciosa y de correcta clasif...

  19. Cardiovascular imaging environment: will the future be cloud-based?

    Science.gov (United States)

    Kawel-Boehm, Nadine; Bluemke, David A

    2017-07-01

    In cardiovascular CT and MR imaging large datasets have to be stored, post-processed, analyzed and distributed. Beside basic assessment of volume and function in cardiac magnetic resonance imaging e.g., more sophisticated quantitative analysis is requested requiring specific software. Several institutions cannot afford various types of software and provide expertise to perform sophisticated analysis. Areas covered: Various cloud services exist related to data storage and analysis specifically for cardiovascular CT and MR imaging. Instead of on-site data storage, cloud providers offer flexible storage services on a pay-per-use basis. To avoid purchase and maintenance of specialized software for cardiovascular image analysis, e.g. to assess myocardial iron overload, MR 4D flow and fractional flow reserve, evaluation can be performed with cloud based software by the consumer or complete analysis is performed by the cloud provider. However, challenges to widespread implementation of cloud services include regulatory issues regarding patient privacy and data security. Expert commentary: If patient privacy and data security is guaranteed cloud imaging is a valuable option to cope with storage of large image datasets and offer sophisticated cardiovascular image analysis for institutions of all sizes.

  20. Leptin and its cardiovascular effects: Focus on angiogenesis

    Directory of Open Access Journals (Sweden)

    Zoya Tahergorabi

    2015-01-01

    Full Text Available Leptin is an endocrine hormone synthesized by adipocytes. It plays a key role in the energy homeostasis in central and peripheral tissues and has additional roles are attributed to it, such as the regulation of reproduction, immune function, bone homeostasis, and angiogenesis. The plasma concentration of leptin significantly increases in obese individuals. In the present review, we give an introduction concerning leptin, its receptors, signaling pathways, and its effect on cardiovascular system, especially on angiogenesis.

  1. Understanding the application of stem cell therapy in cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Sharma RK

    2012-10-01

    Full Text Available Rakesh K Sharma, Donald J Voelker, Roma Sharma, Hanumanth K ReddyUniversity of Arkansas for Medical Sciences, Medical Center of South Arkansas, El Dorado, AR, USAAbstract: Throughout their lifetime, an individual may sustain many injuries and recover spontaneously over a period of time, without even realizing the injury in the first place. Wound healing occurs due to a proliferation of stem cells capable of restoring the injured tissue. The ability of adult stem cells to repair tissue is dependent upon the intrinsic ability of tissues to proliferate. The amazing capacity of embryonic stem cells to give rise to virtually any type of tissue has intensified the search for similar cell lineage in adults to treat various diseases including cardiovascular diseases. The ability to convert adult stem cells into pluripotent cells that resemble embryonic cells, and to transplant those in the desired organ for regenerative therapy is very attractive, and may offer the possibility of treating harmful disease-causing mutations. The race is on to find the best cells for treatment of cardiovascular disease. There is a need for the ideal stem cell, delivery strategies, myocardial retention, and time of administration in the ideal patient population. There are multiple modes of stem cell delivery to the heart with different cell retention rates that vary depending upon method and site of injection, such as intra coronary, intramyocardial or via coronary sinus. While there are crucial issues such as retention of stem cells, microvascular plugging, biodistribution, homing to myocardium, and various proapoptotic factors in the ischemic myocardium, the regenerative potential of stem cells offers an enormous impact on clinical applications in the management of cardiovascular diseases.Keywords: stem cell therapy, stem cell delivery, cardiovascular diseases, myocardial infarction, cardiomyopathy

  2. Mixed connective tissue disease.

    Science.gov (United States)

    Gunnarsson, Ragnar; Hetlevik, Siri Opsahl; Lilleby, Vibke; Molberg, Øyvind

    2016-02-01

    The concept of mixed connective tissue disease (MCTD) as a separate connective tissue disease (CTD) has persisted for more than four decades. High titers of antibodies targeting the U1 small nuclear ribonucleoprotein particle (U1 snRNP) in peripheral blood are a sine qua non for the diagnosis of MCTD, in addition to distinct clinical features including Raynaud's phenomenon (RP), "puffy hands," arthritis, myositis, pleuritis, pericarditis, interstitial lung disease (ILD), and pulmonary hypertension (PH). Recently, population-based epidemiology data from Norway estimated the point prevalence of adult-onset MCTD to be 3.8 per 100,000 and the mean annual incidence to be 2.1 per million per year, supporting the notion that MCTD is the least common CTD. Little is known about the etiology of MCTD, but recent genetic studies have confirmed that MCTD is a strongly HLA (​human leukocyte antigen)-linked disease, as the HLA profiles of MCTD differ distinctly from the corresponding profiles of ethnically matched healthy controls and other CTDs. In the first section of this review, we provide an update on the clinical, immunological, and genetic features of MCTD and discuss the relationship between MCTD and the other CTDs. Then we proceed to discuss the recent advances in therapy and our current understanding of prognosis and prognostic factors, especially those that are associated with the more serious pulmonary and cardiovascular complications of the disease. In the final section, we discuss some of the key, unresolved questions related to anti-RNP-associated diseases and indicate how these questions may be approached in future studies. Copyright © 2016. Published by Elsevier Ltd.

  3. "TRP inflammation" relationship in cardiovascular system.

    Science.gov (United States)

    Numata, Tomohiro; Takahashi, Kiriko; Inoue, Ryuji

    2016-05-01

    Despite considerable advances in the research and treatment, the precise relationship between inflammation and cardiovascular (CV) disease remains incompletely understood. Therefore, understanding the immunoinflammatory processes underlying the initiation, progression, and exacerbation of many cardiovascular diseases is of prime importance. The innate immune system has an ancient origin and is well conserved across species. Its activation occurs in response to pathogens or tissue injury. Recent studies suggest that altered ionic balance, and production of noxious gaseous mediators link to immune and inflammatory responses with altered ion channel expression and function. Among plausible candidates for this are transient receptor potential (TRP) channels that function as polymodal sensors and scaffolding proteins involved in many physiological and pathological processes. In this review, we will first focus on the relevance of TRP channel to both exogenous and endogenous factors related to innate immune response and transcription factors related to sustained inflammatory status. The emerging role of inflammasome to regulate innate immunity and its possible connection to TRP channels will also be discussed. Secondly, we will discuss about the linkage of TRP channels to inflammatory CV diseases, from a viewpoint of inflammation in a general sense which is not restricted to the innate immunity. These knowledge may serve to provide new insights into the pathogenesis of various inflammatory CV diseases and their novel therapeutic strategies.

  4. Acrolein Can Cause Cardiovascular Disease: A Review.

    Science.gov (United States)

    Henning, Robert J; Johnson, Giffe T; Coyle, Jayme P; Harbison, Raymond D

    2017-07-01

    Acrolein is a highly reactive unsaturated aldehyde that is formed during the burning of gasoline and diesel fuels, cigarettes, woods and plastics. In addition, acrolein is generated during the cooking or frying of food with fats or oils. Acrolein is also used in the synthesis of many organic chemicals and as a biocide in agricultural and industrial water supply systems. The total emissions of acrolein in the United States from all sources are estimated to be 62,660 tons/year. Acrolein is classified by the Environmental Protection Agency as a high-priority air and water toxicant. Acrolein can exert toxic effects following inhalation, ingestion, and dermal exposures that are dose dependent. Cardiovascular tissues are particularly sensitive to the toxic effects of acrolein based primarily on in vitro and in vivo studies. Acrolein can generate free oxygen radical stress in the heart, decrease endothelial nitric oxide synthase phosphorylation and nitric oxide formation, form cytoplasmic and nuclear protein adducts with myocyte and vascular endothelial cell proteins and cause vasospasm. In this manner, chronic exposure to acrolein can cause myocyte dysfunction, myocyte necrosis and apoptosis and ultimately lead to cardiomyopathy and cardiac failure. Epidemiological studies of acrolein exposure and toxicity should be developed and treatment strategies devised that prevent or significantly limit acrolein cardiovascular toxicity.

  5. Cannabinoids in the Cardiovascular System.

    Science.gov (United States)

    Ho, Wing S V; Kelly, Melanie E M

    2017-01-01

    Cannabinoids are known to modulate cardiovascular functions including heart rate, vascular tone, and blood pressure in humans and animal models. Essential components of the endocannabinoid system, namely, the production, degradation, and signaling pathways of endocannabinoids have been described not only in the central and peripheral nervous system but also in myocardium, vasculature, platelets, and immune cells. The mechanisms of cardiovascular responses to endocannabinoids are often complex and may involve cannabinoid CB 1 and CB 2 receptors or non-CB 1/2 receptor targets. Preclinical and some clinical studies have suggested that targeting the endocannabinoid system can improve cardiovascular functions in a number of pathophysiological conditions, including hypertension, metabolic syndrome, sepsis, and atherosclerosis. In this chapter, we summarize the local and systemic cardiovascular effects of cannabinoids and highlight our current knowledge regarding the therapeutic potential of endocannabinoid signaling and modulation. © 2017 Elsevier Inc. All rights reserved.

  6. Anxiety Disorders and Cardiovascular Disease.

    Science.gov (United States)

    Celano, Christopher M; Daunis, Daniel J; Lokko, Hermioni N; Campbell, Kirsti A; Huffman, Jeff C

    2016-11-01

    Anxiety and its associated disorders are common in patients with cardiovascular disease and may significantly influence cardiac health. Anxiety disorders are associated with the onset and progression of cardiac disease, and in many instances have been linked to adverse cardiovascular outcomes, including mortality. Both physiologic (autonomic dysfunction, inflammation, endothelial dysfunction, changes in platelet aggregation) and health behavior mechanisms may help to explain the relationships between anxiety disorders and cardiovascular disease. Given the associations between anxiety disorders and poor cardiac health, the timely and accurate identification and treatment of these conditions is of the utmost importance. Fortunately, pharmacologic and psychotherapeutic interventions for the management of anxiety disorders are generally safe and effective. Further study is needed to determine whether interventions to treat anxiety disorders ultimately impact both psychiatric and cardiovascular health.

  7. Cardiovascular nuclear medicine and MRI

    International Nuclear Information System (INIS)

    Reiber, J.H.C.; Wall, E.E. van der

    1992-01-01

    This book is based on a meeting of the Working Group on Nuclear Cardiology, which held March 22-23,1991 under the auspices of the European Society of Cardiology and the Interuniversity Cardiology Institute of the Netherlands, and on the Second International Symposium on Computer Applications in Nuclear Medicine and Cardiac Magnetic Resonance Imaging, which was held March 20-22,1991 in Rotterdam, the Netherlands. It covers almost every aspect of quantitative cardio-vascular nuclear medicine and magnetic resonance imaging. The main topics are: single photon emission computed tomography (technical aspects); new development in cardiovascular nuclear medicine; advances in cardiovascular imaging; cardiovascular clinical applications; and cardiac magnetic resonance imaging. (A.S.). refs.; figs.; tabs

  8. Sex differences in cardiovascular function

    Czech Academy of Sciences Publication Activity Database

    Kolář, František; Ošťádal, Bohuslav

    2013-01-01

    Roč. 207, č. 4 (2013), s. 584-587 ISSN 1748-1708 Institutional support: RVO:67985823 Keywords : heart * vascular * risk factors * sex Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 4.251, year: 2013

  9. Platelet-derived growth factor-C and -D in the cardiovascular system and diseases.

    Science.gov (United States)

    Lee, Chunsik; Li, Xuri

    2017-10-12

    The cardiovascular system is among the first organs formed during development and is pivotal for the formation and function of the rest of the organs and tissues. Therefore, the function and homeostasis of the cardiovascular system are finely regulated by many important molecules. Extensive studies have shown that platelet-derived growth factors (PDGFs) and their receptors are critical regulators of the cardiovascular system. Even though PDGF-C and PDGF-D are relatively new members of the PDGF family, their critical roles in the cardiovascular system as angiogenic and survival factors have been amply demonstrated. Understanding the functions of PDGF-C and PDGF-D and the signaling pathways involved may provide novel insights into both basic biomedical research and new therapeutic possibilities for the treatment of cardiovascular diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. The Light and Shadow of Senescence and Inflammation in Cardiovascular Pathology and Regenerative Medicine

    Directory of Open Access Journals (Sweden)

    Laura Iop

    2017-01-01

    Full Text Available Recent epidemiologic studies evidence a dramatic increase of cardiovascular diseases, especially associated with the aging of the world population. During aging, the progressive impairment of the cardiovascular functions results from the compromised tissue abilities to protect the heart against stress. At the molecular level, in fact, a gradual weakening of the cellular processes regulating cardiovascular homeostasis occurs in aging cells. Atherosclerosis and heart failure are particularly correlated with aging-related cardiovascular senescence, that is, the inability of cells to progress in the mitotic program until completion of cytokinesis. In this review, we explore the intrinsic and extrinsic causes of cellular senescence and their role in the onset of these cardiovascular pathologies. Additionally, we dissect the effects of aging on the cardiac endogenous and exogenous reservoirs of stem cells. Finally, we offer an overview on the strategies of regenerative medicine that have been advanced in the quest for heart rejuvenation.

  11. [Remodeling of Cardiovascular System: Causes and Consequences].

    Science.gov (United States)

    Lopatina, E V; Kipenko, A V; Penniyaynen, V A; Pasatetckaia, N A; Tsyrline, V A

    2016-01-01

    Literature and our data suggest the regulatory action of a number of biologically active substances (catecholamines, cardiac glycosides, β-blockers, angiotensin-converting-enzyme inhibitor) on the growth and proliferation of heart cells. By using of organotypic tissue culture has proved that the basis of this regulation is the ability of test substances, receptor- or transducer-mediated signaling to modulate the function of Na⁺, K⁺-ATPase. There is a delay in the development of vascular smooth muscle in the late postnatal period in rats with the blockade of the sympathetic nervous system in the prenatal period. The relationship between vascular remodeling and contractile activity is described. It seems that one of the causes of high blood pressure is a remodeling of the cardiovascular system, which precedes the development of hypertension.

  12. Photochemical tissue bonding

    Science.gov (United States)

    Redmond, Robert W [Brookline, MA; Kochevar, Irene E [Charlestown, MA

    2012-01-10

    Photochemical tissue bonding methods include the application of a photosensitizer to a tissue and/or tissue graft, followed by irradiation with electromagnetic energy to produce a tissue seal. The methods are useful for tissue adhesion, such as in wound closure, tissue grafting, skin grafting, musculoskeletal tissue repair, ligament or tendon repair and corneal repair.

  13. Possible Muscle Repair in the Human Cardiovascular System.

    Science.gov (United States)

    Sommese, Linda; Zullo, Alberto; Schiano, Concetta; Mancini, Francesco P; Napoli, Claudio

    2017-04-01

    The regenerative potential of tissues and organs could promote survival, extended lifespan and healthy life in multicellular organisms. Niches of adult stemness are widely distributed and lead to the anatomical and functional regeneration of the damaged organ. Conversely, muscular regeneration in mammals, and humans in particular, is very limited and not a single piece of muscle can fully regrow after a severe injury. Therefore, muscle repair after myocardial infarction is still a chimera. Recently, it has been recognized that epigenetics could play a role in tissue regrowth since it guarantees the maintenance of cellular identity in differentiated cells and, therefore, the stability of organs and tissues. The removal of these locks can shift a specific cell identity back to the stem-like one. Given the gradual loss of tissue renewal potential in the course of evolution, in the last few years many different attempts to retrieve such potential by means of cell therapy approaches have been performed in experimental models. Here we review pathways and mechanisms involved in the in vivo repair of cardiovascular muscle tissues in humans. Moreover, we address the ongoing research on mammalian cardiac muscle repair based on adult stem cell transplantation and pro-regenerative factor delivery. This latter issue, involving genetic manipulations of adult cells, paves the way for developing possible therapeutic strategies in the field of cardiovascular muscle repair.

  14. Cardiovascular effects of basal insulins.

    Science.gov (United States)

    Mannucci, Edoardo; Giannini, Stefano; Dicembrini, Ilaria

    2015-01-01

    Basal insulin is an important component of treatment for both type 1 and type 2 diabetes. One of the principal aims of treatment in patients with diabetes is the prevention of diabetic complications, including cardiovascular disease. There is some evidence, although controversial, that attainment of good glycemic control reduces long-term cardiovascular risk in both type 1 and type 2 diabetes. The aim of this review is to provide an overview of the potential cardiovascular safety of the different available preparations of basal insulin. Current basal insulin (neutral protamine Hagedorn [NPH], or isophane) and basal insulin analogs (glargine, detemir, and the more recent degludec) differ essentially by various measures of pharmacokinetic and pharmacodynamic effects in the bloodstream, presence and persistence of peak action, and within-subject variability in the glucose-lowering response. The currently available data show that basal insulin analogs have a lower risk of hypoglycemia than NPH human insulin, in both type 1 and type 2 diabetes, then excluding additional harmful effects on the cardiovascular system mediated by activation of the adrenergic system. Given that no biological rationale for a possible difference in cardiovascular effect of basal insulins has been proposed so far, available meta-analyses of publicly disclosed randomized controlled trials do not show any signal of increased risk of major cardiovascular events between the different basal insulin analogs. However, the number of available cardiovascular events in these trials is very small, preventing any clear-cut conclusion. The results of an ongoing clinical trial comparing glargine and degludec with regard to cardiovascular safety will provide definitive evidence.

  15. Regenerative medicine in cardiovascular disease : from tissue enginering to tissue regeneration

    NARCIS (Netherlands)

    Grauss, Robert Willem

    2008-01-01

    The general introduction in Chapter 1 of this thesis provides an overview of the emerging field of regenerative medicine, and its different areas of technology. Contemporary approaches to heart valve repair and replacement by mechanical and biological prosthesis, as well as their limitations are

  16. Psoriasis and cardiovascular risk: Immune-mediated crosstalk between metabolic, vascular and autoimmune inflammation

    Directory of Open Access Journals (Sweden)

    R.A. Kölliker Frers

    2015-03-01

    Results and conclusions: Psoriasis and psoriatic arthritis diseases illustrate that immune-mediated activated crossroads of inflammation beyond enhanced cardiovascular risk factors are the result of an interplay between different proatherogenic mediators derived from metabolic, vascular and autoimmune joint and skin inflamed target tissue. Consistent with this point of view, psoriasis and psoriatic arthritis diseases offer an invaluable opportunity to reinforce our knowledge about atherosclerotic cardiovascular disease.

  17. [Cardiovascular depression and intravascular hemolysis secondary to ethanol injection for arteriovenous malformation].

    Science.gov (United States)

    Cai, Mei-Hua; Su, Li-Xin; Qiu, Lin

    2016-08-01

    Ethanol is the only liquid embolization agent which can cure arteriovenous malformation. Complications of ethanol embolization are not rare including local tissue injury, intravascular hemolysis and cardiovascular depression even collapse, etc. This report presented a case of long time cardiovascular depression and intravascular hemolysis secondary to ethanol embolotherapy of right ear. In order to avoid the fatal complications that are associated with ethanol sclerotherapy, anesthesiologists should consider the use of continuously invasive hemodynamic monitoring while surgeons should carefully choose the dose of ethanol.

  18. Tissue Engineering and Regenerative Strategies to Replicate Biocomplexity of Vascular Elastic Matrix Assembly

    OpenAIRE

    Bashur, Chris A.; Venkataraman, Lavanya; Ramamurthi, Anand

    2012-01-01

    Cardiovascular tissues exhibit architecturally complex extracellular matrices, of which the elastic matrix forms a major component. The elastic matrix critically maintains native structural configurations of vascular tissues, determines their ability to recoil after stretch, and regulates cell signaling pathways involved in morphogenesis, injury response, and inflammation via biomechanical transduction. The ability to tissue engineer vascular replacements that incorporate elastic matrix super...

  19. Intracardiac flow patterns studied by cine MR flow imaging

    International Nuclear Information System (INIS)

    Underwood, S.R.; Firmin, D.N.; Klipstein, R.H.; Rees, R.S.O.; Longmore, D.B.

    1986-01-01

    Velocity mapping by means of cine-MR imaging allows accurate measurement of velocity and flow within the cardiovascular system. A cine display and color coding simplify interpretation. The author have used the technique in a variety of patients to illustrate its potential. Velocity mapping in coronary artery by pass grafts in six patients provided a measure of graft function. Coronary artery velocities were measured in three subjects. Flow was measured through defects in the atrial septum, the ventricular septum, and a Gerbode defect. Velocity was reduced distal to coarctation of the aorta and was increased at the level of a partial venous occlusion by thrombosis. In a patient with isomerism, velocity mapping in the central vessels aided interpretation. Cine-MR imaging velocity mapping combined with conventional imaging yields important functional information on the cardiovascular system

  20. Cardiovascular effects of bariatric surgery.

    Science.gov (United States)

    Beamish, Andrew J; Olbers, Torsten; Kelly, Aaron S; Inge, Thomas H

    2016-12-01

    Obesity is a major global health problem, and its multisystem effects are inextricably linked with elevated cardiovascular risk and adverse outcomes. The cardiovascular benefits of reversing obesity in adults are well-established. Compared with other weight-loss strategies, programmes that incorporate bariatric surgery for weight loss are beneficial for sustained BMI reduction. A marked improvement in cardiovascular risk factors, including hypertension, dyslipidaemia, inflammation, and type 2 diabetes mellitus, has been observed after bariatric surgery. This broad improvement in cardiovascular risk profile has led to substantial reductions in the risk of myocardial infarction, stroke, and death. As with all procedures, the benefits of bariatric surgery must be weighed against its potential risks. Modern bariatric surgery has an excellent safety profile, but important limitations remain, including the potential for surgical complications and nutritional deficiencies, and the lifelong requirement for nutritional supplementation. Surgery should be considered in patients with severe obesity, especially those with cardiovascular comorbidities. In this Review, we summarize the current management options for patients with obesity, and discuss the effects of bariatric surgery on cardiovascular risk factors and outcomes.

  1. The cardiovascular effects of insulin.

    Science.gov (United States)

    Younk, Lisa M; Lamos, Elizabeth M; Davis, Stephen N

    2014-07-01

    Cardiovascular disease remains one of the leading causes of morbidity and mortality in diabetes mellitus. A causal link between insulin, atherosclerosis and cardiovascular risk has been investigated at the basic science level and studied in large clinical trials. The cardiovascular actions of insulin and its role at the level of the endothelium will be reviewed. Cardiovascular outcomes in several large diabetes trials where insulin management was prominent will be summarized. The vascular actions of insulin are complex and mediated primarily via nitric oxide and endothelin-1. It appears that insulin resistance, rather than hyperinsulinemia itself, increases cardiovascular risk. In fact, hyperinsulinemia in the setting of normal beta cell function protects obese and insulin-resistant individuals from type 2 diabetes. Large clinical trials have supported that insulin management is not associated with increased adverse outcomes. A multifactorial approach targeting modifiable risk factors, including smoking cessation, blood pressure and lipid management, reduces cardiovascular risk. Therapy goals should be individualized and hypoglycemia, especially in individuals receiving insulin management, should be strictly avoided.

  2. Binding sites for endothelin-1 in rat tissues: An autoradiographic study

    International Nuclear Information System (INIS)

    Koseki, C.; Imai, M.; Hirata, Y.; Yanagisawa, M.; Masaki, T.

    1989-01-01

    By tissue autoradiography in the rat, we demonstrated that receptors for endothelin-1 (ET-1) were distributed not only in the cardiovascular system but also in the noncardiovascular organs including the brain, lung, intestine, etc. In the brain, the receptors were mainly found in the basal ganglia and brainstem, in which nuclei are known to be cardiovascular regulatory sites. In addition to its direct vasoconstricting action, ET-1 may exert neural cardiovascular control as a neuropeptide

  3. Tissue Photolithography

    Science.gov (United States)

    Wade, Lawrence A.; Kartalov, Emil; Shibata, Darryl; Taylor, Clive

    2011-01-01

    Tissue lithography will enable physicians and researchers to obtain macromolecules with high purity (greater than 90 percent) from desired cells in conventionally processed, clinical tissues by simply annotating the desired cells on a computer screen. After identifying the desired cells, a suitable lithography mask will be generated to protect the contents of the desired cells while allowing destruction of all undesired cells by irradiation with ultraviolet light. The DNA from the protected cells can be used in a number of downstream applications including DNA sequencing. The purity (i.e., macromolecules isolated form specific cell types) of such specimens will greatly enhance the value and information of downstream applications. In this method, the specific cells are isolated on a microscope slide using photolithography, which will be faster, more specific, and less expensive than current methods. It relies on the fact that many biological molecules such as DNA are photosensitive and can be destroyed by ultraviolet irradiation. Therefore, it is possible to protect the contents of desired cells, yet destroy undesired cells. This approach leverages the technologies of the microelectronics industry, which can make features smaller than 1 micrometer with photolithography. A variety of ways has been created to achieve identification of the desired cell, and also to designate the other cells for destruction. This can be accomplished through chrome masks, direct laser writing, and also active masking using dynamic arrays. Image recognition is envisioned as one method for identifying cell nuclei and cell membranes. The pathologist can identify the cells of interest using a microscopic computerized image of the slide, and appropriate custom software. In one of the approaches described in this work, the software converts the selection into a digital mask that can be fed into a direct laser writer, e.g. the Heidelberg DWL66. Such a machine uses a metalized glass plate (with

  4. Ceruloplasmin and cardiovascular disease

    Science.gov (United States)

    Fox, P. L.; Mazumder, B.; Ehrenwald, E.; Mukhopadhyay, C. K.

    2000-01-01

    Transition metal ion-mediated oxidation is a commonly used model system for studies of the chemical, structural, and functional modifications of low-density lipoprotein (LDL). The physiological relevance of studies using free metal ions is unclear and has led to an exploration of free metal ion-independent mechanisms of oxidation. We and others have investigated the role of human ceruloplasmin (Cp) in oxidative processes because it the principal copper-containing protein in serum. There is an abundance of epidemiological data that suggests that serum Cp may be an important risk factor predicting myocardial infarction and cardiovascular disease. Biochemical studies have shown that Cp is a potent catalyst of LDL oxidation in vitro. The pro-oxidant activity of Cp requires an intact structure, and a single copper atom at the surface of the protein, near His(426), is required for LDL oxidation. Under conditions where inhibitory protein (such as albumin) is present, LDL oxidation by Cp is optimal in the presence of superoxide, which reduces the surface copper atom of Cp. Cultured vascular endothelial and smooth muscle cells also oxidize LDL in the presence of Cp. Superoxide release by these cells is a critical factor regulating the rate of oxidation. Cultured monocytic cells, when activated by zymosan, can oxidize LDL, but these cells are unique in their secretion of Cp. Inhibitor studies using Cp-specific antibodies and antisense oligonucleotides show that Cp is a major contributor to LDL oxidation by these cells. The role of Cp in lipoprotein oxidation and atherosclerotic lesion progression in vivo has not been directly assessed and is an important area for future studies.

  5. Obesity Decreases Perioperative Tissue Oxygenation

    Science.gov (United States)

    Kabon, Barbara; Nagele, Angelika; Reddy, Dayakar; Eagon, Chris; Fleshman, James W.; Sessler, Daniel I.; Kurz, Andrea

    2005-01-01

    Background: Obesity is an important risk factor for surgical site infections. The incidence of surgical wound infections is directly related to tissue perfusion and oxygenation. Fat tissue mass expands without a concomitant increase in blood flow per cell, which might result in a relative hypoperfusion with decreased tissue oxygenation. Consequently, we tested the hypotheses that perioperative tissue oxygen tension is reduced in obese surgical patients. Furthermore, we compared the effect of supplemental oxygen administration on tissue oxygenation in obese and non-obese patients. Methods: Forty-six patients undergoing major abdominal surgery were assigned to one of two groups according to their body mass index (BMI): BMI < 30 kg/m2 (non-obese) and BMI ≥ 30 kg/m2 (obese). Intraoperative oxygen administration was adjusted to arterial oxygen tensions of ≈150 mmHg and ≈300 mmHg in random order. Anesthesia technique and perioperative fluid management were standardized. Subcutaneous tissue oxygen tension was measured with a polarographic electrode positioned within a subcutaneous tonometer in the lateral upper arm during surgery, in the recovery room, and on the first postoperative day. Postoperative tissue oxygen was also measured adjacent to the wound. Data were compared with unpaired two tailed t-tests and Wilcoxon rank-sum tests; P < 0.05 was considered statistically significant. Results: Intraoperative subcutaneous tissue oxygen tension was significantly less in the obese patients at baseline (36 vs. 57 mmHg, P = 0.002) and with supplemental oxygen administration (47 vs. 76 mmHg, P = 0.014). Immediate postoperative tissue oxygen tension was also significantly less in subcutaneous tissue of the upper arm (43 vs. 54 mmHg, P = 0.011) as well as near the incision (42 vs. 62 mmHg, P = 0.012) in obese patients. In contrast, tissue oxygen tension was comparable in each group on the first postoperative morning. Conclusion: Wound and tissue hypoxia were common in obese

  6. Clinical Assessment of Cardiovascular and Autonomic Function

    Directory of Open Access Journals (Sweden)

    Diego Benitez

    2004-10-01

    Full Text Available This paper presents a non-invasive virtual medical instrument for the clinical assessment of cardiovascular and autonomic function. The virtual instrument was developed with the aim of analysing and understanding the physiological changes that occurs in the heart and circulation during vasovagal blackout attacks. The automated virtual instrument allows impedance cardiography analysis, time and frequency heart rate and blood pressure variability analysis, invasive and non-invasive baroreflex sensitivity assessment and forearm blood flow measurements. Using this virtual instrument five control subjects (3 male, mean age 30.6 ± 5.4 and five vasovagal syncope suffers (2 male, mean age 38.6 ± 6.3 were used in a study to try to identify the differences between the two groups to tilt induced syncope. The results obtained suggest that there are fundamental differences in the physiological responses to orthostatic stress between vasovagal patients and controls, which are evident before the onset of major haemodynamic changes.

  7. Role of extracellular vesicles in de novo mineralization: an additional novel mechanism of cardiovascular calcification.

    Science.gov (United States)

    New, Sophie E P; Aikawa, Elena

    2013-08-01

    Extracellular vesicles are membrane micro/nanovesicles secreted by many cell types into the circulation and the extracellular milieu in physiological and pathological conditions. Evidence suggests that extracellular vesicles, known as matrix vesicles, play a role in the mineralization of skeletal tissue, but emerging ultrastructural and in vitro studies have demonstrated their contribution to cardiovascular calcification as well. Cells involved in the progression of cardiovascular calcification release active vesicles capable of nucleating hydroxyapatite on their membranes. This review discusses the role of extracellular vesicles in cardiovascular calcification and elaborates on this additional mechanism of calcification as an alternative pathway to the currently accepted mechanism of biomineralization via osteogenic differentiation.

  8. The Role of Extracellular Vesicles in De Novo Mineralization: An Additional Novel Mechanism of Cardiovascular Calcification

    Science.gov (United States)

    New, Sophie E. P.; Aikawa, Elena

    2013-01-01

    Extracellular vesicles are membrane micro/nanovesicles secreted by many cell types into the circulation and the extracellular milieu in physiological and pathological conditions. Evidence suggests that extracellular vesicles, known as matrix vesicles, play a role in the mineralization of skeletal tissue, but emerging ultrastructural and in vitro studies have demonstrated their contribution to cardiovascular calcification as well. Cells involved in the progression of cardiovascular calcification release active vesicles capable of nucleating hydroxyapatite on their membranes. This review discusses the role of extracellular vesicles in cardiovascular calcification, and elaborates on this additional mechanism of calcification as an alternative pathway to the currently accepted mechanism of biomineralization via osteogenic differentiation. PMID:23766262

  9. Live dynamic analysis of the developing cardiovascular system in mice

    Science.gov (United States)

    Lopez, Andrew L.; Wang, Shang; Larin, Kirill V.; Larina, Irina V.

    2017-02-01

    The study of the developing cardiovascular system in mice is important for understanding human cardiogenesis and congenital heart defects. Our research focuses on imaging early development in the mouse embryo to specifically understand cardiovascular development under the regulation of dynamic factors like contractile force and blood flow using optical coherence tomography (OCT). We have previously developed an OCT based approach that combines static embryo culture and advanced image processing with computational modeling to live-image mouse embryos and obtain 4D (3D+time) cardiodynamic datasets. Here we present live 4D dynamic blood flow imaging of the early embryonic mouse heart in correlation with heart wall movement. We are using this approach to understand how specific mutations impact heart wall dynamics, and how this influences flow patterns and cardiogenesis. We perform studies in mutant embryos with cardiac phenotypes such as myosin regulatory light chain 2, atrial isoform (Mlc2a). This work is brings us closer to understanding the connections between dynamic mechanical factors and gene programs responsible for early cardiovascular development.

  10. In vivo tissue engineering of musculoskeletal tissues.

    Science.gov (United States)

    McCullen, Seth D; Chow, Andre G Y; Stevens, Molly M

    2011-10-01

    Tissue engineering of musculoskeletal tissues often involves the in vitro manipulation and culture of progenitor cells, growth factors and biomaterial scaffolds. Though in vitro tissue engineering has greatly increased our understanding of cellular behavior and cell-material interactions, this methodology is often unable to recreate tissue with the hierarchical organization and vascularization found within native tissues. Accordingly, investigators have focused on alternative in vivo tissue engineering strategies, whereby the traditional triad (cells, growth factors, scaffolds) or a combination thereof are directly implanted at the damaged tissue site or within ectopic sites capable of supporting neo-tissue formation. In vivo tissue engineering may offer a preferential route for regeneration of musculoskeletal and other tissues with distinct advantages over in vitro methods based on the specific location of endogenous cultivation, recruitment of autologous cells, and patient-specific regenerated tissues. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Applications of phase-contrast velocimetry sequences in cardiovascular imaging.

    Science.gov (United States)

    Caroff, J; Bière, L; Trebuchet, G; Nedelcu, C; Sibileau, E; Beregi, J-P; Aubé, C; Furber, A; Willoteaux, S

    2012-03-01

    To describe and illustrate the main applications of phase-contrast flow quantification in cardiovascular imaging. Phase-contrast velocimetry sequences provide an accurate, reliable, reproducible and non-invasive study of blood flow, information which is sometimes not available from other investigation methods. The haemodynamic information obtained from these complement MRI angiography images. They appear to have a range of clinical applications, firstly improving pathophysiological understanding but also contributing to the treatment and follow-up strategy after surgical or endovascular treatment. Copyright © 2012 Éditions Françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  12. Air Pollution and Cardiovascular Disease: A Review.

    Science.gov (United States)

    Patel, Vivek; Kantipudi, Neha; Jones, Graham; Upton, Adrian; Kamath, Markad V

    2016-01-01

    Air pollution is comprised of different compounds and particulate matter (PM) of sizes 2.5 and 10 μm, with the former size posing the greatest danger to humans. Evidence suggests that the global rise in air pollution levels during the past century is correlated with the increased incidence of diseases of the cardiovascular system. On a global scale, 7 million individuals died as a result of the effects of air pollution in 2012. Air pollution leads to tremendous amounts of financial burden (in 2010, $16 trillion in the US and Europe) on the health-care system. The severity of effects experienced by varying populations due to air pollution can differ due to locale, length of exposure, weather conditions, residential proximity to major highways or factories, and soil aridity. Pollutants affect the heart, blood vessels, and blood at a molecular level through proinflammatory or oxidative stress response, autonomic nervous system imbalance, and the direct permeation of harmful compounds into the tissue. The dysfunction of cells and biological processes of the cardiovascular system due to PM leads to an increased prevalence of cardiovascular diseases (CVDs) such as atherosclerosis, hypertension, myocardial infarction, thrombosis, and restricted valve motion. Studies in countries such as China have shown an increase of 0.25% in ischemic heart disease (IHD) mortality and a 0.27% increase in IHD morbidity due to a 10 μg/m3 increase in PM. In a study conducted in the US, PM2.5 concentrations ranged from 9.2-22.6 μg/m3, and every 5-μg/m3 increase in PM2.5 caused coronary calcification to increase by 4.1 Agatston units/yr. Studies on traffic-related air pollution found that nonhypertensive participants residing within 100 m of major roadways experienced an increase in systolic (0.35 mmHg) and diastolic (0.22 mmHg) blood pressure as a result of increases in traffic. The progression of CVD due to pollution has been found to fluctuate within individuals based on age, gender

  13. Functional Characterization of Preadipocytes Derived from Human Periaortic Adipose Tissue

    Directory of Open Access Journals (Sweden)

    Diana Vargas

    2017-01-01

    Full Text Available Adipose tissue can affect the metabolic control of the cardiovascular system, and its anatomic location can affect the vascular function differently. In this study, biochemical and phenotypical characteristics of adipose tissue from periaortic fat were evaluated. Periaortic and subcutaneous adipose tissues were obtained from areas surrounding the ascending aorta and sternotomy incision, respectively. Adipose tissues were collected from patients undergoing myocardial revascularization or mitral valve replacement surgery. Morphological studies with hematoxylin/eosin and immunohistochemical assay were performed in situ to quantify adipokine expression. To analyze adipogenic capacity, adipokine expression, and the levels of thermogenic proteins, adipocyte precursor cells were isolated from periaortic and subcutaneous adipose tissues and induced to differentiation. The precursors of adipocytes from the periaortic tissue accumulated less triglycerides than those from the subcutaneous tissue after differentiation and were smaller than those from subcutaneous adipose tissue. The levels of proteins involved in thermogenesis and energy expenditure increased significantly in periaortic adipose tissue. Additionally, the expression levels of adipokines that affect carbohydrate metabolism, such as FGF21, increased significantly in mature adipocytes induced from periaortic adipose tissue. These results demonstrate that precursors of periaortic adipose tissue in humans may affect cardiovascular events and might serve as a target for preventing vascular diseases.

  14. Vascular Aging: Implications for Cardiovascular Disease and Therapy

    Science.gov (United States)

    Ghebre, Yohannes T; Yakubov, Eduard; Wong, Wing Tak; Krishnamurthy, Prasanna; Sayed, Nazish; Sikora, Andrew G; Bonnen, Mark D

    2017-01-01

    The incidence and prevalence of cardiovascular disease is highest among the elderly, in part, due to deleterious effects of advancing age on the heart and blood vessels. Aging, a known cardiovascular risk factor, is progressively associated with structural and functional changes to the vasculature including hemodynamic disturbance due to increased oxidative stress, premature cellular senescence and impairments in synthesis and/or secretion of endothelium-derived vasoactive molecules. These molecular and physiological changes lead to vessel wall stiffening and thickening, as well as other vascular complications that culminate to loss of vascular tone regulation and endothelial function. Intriguingly, the vessel wall, a biochemically active structure composed of collagen, connective tissue, smooth muscle and endothelial cells, is adversely affected by processes involved in premature or normal aging. Notably, the inner most layer of the vessel wall, the endothelium, becomes senescent and dysfunctional with advancing age. As a result, its ability to release vasoactive molecules such as acetylcholine (ACh), prostacyclin (PGI2), endothelium-derived hyperpolarizing factor (EDHF), and nitric oxide (NO) is reduced and the cellular response to these molecules is also impaired. By contrast, the vascular endothelium increases its generation and release of reactive oxygen (ROS) and nitrogen (RNS) species, vasoconstrictors such as endothelin (ET) and angiotensin (AT), and endogenous inhibitors of NO synthases (NOSs) to block NO. This skews the balance of the endothelium in favor of the release of highly tissue reactive and harmful molecules that promote DNA damage, telomere erosion, senescence, as well as stiffened and hardened vessel wall that is prone to the development of hypertension, diabetes, atherosclerosis and other cardiovascular risk factors. This Review discusses the impact of advancing age on cardiovascular health, and highlights the cellular and molecular mechanisms

  15. MicroRNAs Control Macrophage Formation and Activation: The Inflammatory Link between Obesity and Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Richard Cheng-An Chang

    2014-07-01

    Full Text Available Activation and recruitment of resident macrophages in tissues in response to physiological stress are crucial regulatory processes in promoting the development of obesity-associated metabolic disorders and cardiovascular diseases. Recent studies have provided compelling evidence that microRNAs play important roles in modulating monocyte formation, macrophage maturation, infiltration into tissues and activation. Macrophage-dependent systemic physiological and tissue-specific responses also involve cell-cell interactions between macrophages and host tissue niche cell components, including other tissue-resident immune cell lineages, adipocytes, vascular smooth muscle and others. In this review, we highlight the roles of microRNAs in regulating the development and function of macrophages in the context of obesity, which could provide insights into the pathogenesis of obesity-related metabolic syndrome and cardiovascular diseases.

  16. A "sweet-spot" for fluid-induced oscillations in the conditioning of stem cell-based engineered heart valve tissues.

    Science.gov (United States)

    Williams, Alexander; Nasim, Sana; Salinas, Manuel; Moshkforoush, Arash; Tsoukias, Nikolaos; Ramaswamy, Sharan

    2017-12-08

    Fluid-induced shear stresses are involved in the development of cardiovascular tissues. In a tissue engineering framework, this stimulus has also been considered as a mechanical regulator of stem cell differentiation. We recently demonstrated that the fluid-oscillating effect in combination with a physiologically-relevant shear stress magnitude contributes to the formation of stem cell-derived de novo heart valve tissues. However, the range of oscillations necessary to induce favorable gene expression and engineered tissue formation is unknown. In this study, we took a computational approach to establish a range of oscillatory shear stresses that may optimize in vitro valvular tissue growth. Taking a biomimetic approach, three physiologically-relevant flow waveforms from the human: (i) aorta, (ii) pulmonary artery and (iii) superior vena cava were utilized to simulate pulsatile flow conditions within a bioreactor that housed 3 tissue specimens. Results were compared to non-physiological pulsatile flow (NPPF) and cyclic flexure-steady flow (Flex-Flow) conditions. The oscillatory shear index (OSI) was used to quantify the fluid-induced oscillations occurring on the specimen surfaces. The range of mean OSI under the physiological conditions investigated was found to be 0.18 ≤ OSI ≤ 0.23. On the other hand, NPPF and Flex-Flow environments yielded a mean OSI of 0.37 and 0.11 respectively, which were 46% higher and 45% lower than physiological conditions. Moreover, we subsequently conducted OSI-based human bone marrow stem cell (HBMSC) culture experiments which resulted in preferential valvular gene expression and phenotype (significant upregulation of BMP, KLF2A, CD31 and α-SMA using an OSI of 0.23 in comparison to a lower OSI of 0.10 or a higher OSI of 0.38; p OSI exists in the mechanical conditioning of tissue engineered heart valves grown from stem cell sources. We conclude that in vitro heart valve matrix development could be further enhanced by simultaneous

  17. Modelling and Simulating the Adhesion and Detachment of Chondrocytes in Shear Flow

    Science.gov (United States)

    Hao, Jian; Pan, Tsorng-Whay; Rosenstrauch, Doreen

    Chondrocytes are typically studied in the environment where they normally reside such as the joints in hips, intervertebral disks or the ear. For example, in [SKE+99], the effect of seeding duration on the strength of chondrocyte adhesion to articulate cartilage has been studied in shear flow chamber since such adhesion may play an important role in the repair of articular defects by maintaining cells in positions where their biosynthetic products can contribute to the repair process. However, in this investigation, we focus mainly on the use of auricular chondrocytes in cardiovascular implants. They are abundant, easily and efficiently harvested by a minimally invasive technique. Auricular chondrocytes have ability to produce collagen type-II and other important extracellular matrix constituents; this allows them to adhere strongly to the artificial surfaces. They can be genetically engineered to act like endothelial cells so that the biocompatibility of cardiovascular prothesis can be improved. Actually in [SBBR+02], genetically engineered auricular chondrocytes can be used to line blood-contacting luminal surfaces of left ventricular assist device (LVAD) and a chondrocyte-lined LVAD has been planted into the tissue-donor calf and the results in vivo have proved the feasibility of using autologous auricular chondrocytes to improve the biocompatibility of the blood-biomaterial interface in LVADs and cardiovascular prothesis. Therefore, cultured chondrocytes may offer a more efficient and less invasive means of covering artificial surface with a viable and adherent cell layer.

  18. Design Approaches to Myocardial and Vascular Tissue Engineering.

    Science.gov (United States)

    Akintewe, Olukemi O; Roberts, Erin G; Rim, Nae-Gyune; Ferguson, Michael A H; Wong, Joyce Y

    2017-06-21

    Engineered tissues represent an increasingly promising therapeutic approach for correcting structural defects and promoting tissue regeneration in cardiovascular diseases. One of the challenges associated with this approach has been the necessity for the replacement tissue to promote sufficient vascularization to maintain functionality after implantation. This review highlights a number of promising prevascularization design approaches for introducing vasculature into engineered tissues. Although we focus on encouraging blood vessel formation within myocardial implants, we also discuss techniques developed for other tissues that could eventually become relevant to engineered cardiac tissues. Because the ultimate solution to engineered tissue vascularization will require collaboration between wide-ranging disciplines such as developmental biology, tissue engineering, and computational modeling, we explore contributions from each field.

  19. Skin Autofluorescence as Marker of Tissue Advanced Glycation End-Products Accumulation in Formerly Preeclamptic Women

    NARCIS (Netherlands)

    Coffeng, S.M.; Blaauw, Judith; Souwer, E.T.; Rakhorst, G.; Smit, A.J.; Graaff, R.; van Doormaal, J.J.; Aarnoudse, J.G.; Faas, M.M.; van Pampus, Maria

    2011-01-01

    Condensation. In women with a history of preeclampsia skin autofluorescence as marker of tissue AGEs accumulation is increased, supporting a common causal metabolic or vascular link between preeclampsia and cardiovascular diseases. Objective. To investigate whether skin autofluorescence (AF), as

  20. Tissue engineering; strategies, tissues, and biomaterials.

    Science.gov (United States)

    Bakhshandeh, Behnaz; Zarrintaj, Payam; Oftadeh, Mohammad Omid; Keramati, Farid; Fouladiha, Hamideh; Sohrabi-Jahromi, Salma; Ziraksaz, Zarrintaj

    2017-10-01

    Current tissue regenerative strategies rely mainly on tissue repair by transplantation of the synthetic/natural implants. However, limitations of the existing strategies have increased the demand for tissue engineering approaches. Appropriate cell source, effective cell modification, and proper supportive matrices are three bases of tissue engineering. Selection of appropriate methods for cell stimulation, scaffold synthesis, and tissue transplantation play a definitive role in successful tissue engineering. Although the variety of the players are available, but proper combination and functional synergism determine the practical efficacy. Hence, in this review, a comprehensive view of tissue engineering and its different aspects are investigated.

  1. Skin autofluorescence predicts cardiovascular mortality in patients on chronic hemodialysis.

    Science.gov (United States)

    Kimura, Hiroshi; Tanaka, Kenichi; Kanno, Makoto; Watanabe, Kimio; Hayashi, Yoshimitsu; Asahi, Koichi; Suzuki, Hodaka; Sato, Keiji; Sakaue, Michiaki; Terawaki, Hiroyuki; Nakayama, Masaaki; Miyata, Toshio; Watanabe, Tsuyoshi

    2014-10-01

    Tissue accumulation of advanced glycation end products (AGE) is thought to contribute to the progression of cardiovascular disease (CVD). Skin autofluorescence, a non-invasive measure of AGE accumulation using autofluorescence of the skin under ultraviolet light, has been reported to be an independent predictor of mortality associated with CVD in Caucasian patients on chronic hemodialysis. The aim of this study was to assess the predictive value of skin autofluorescence on all-cause and cardiovascular mortality in non-Caucasian (Japanese) patients on chronic hemodialysis. Baseline skin autofluorescence was measured with an autofluorescence reader in 128 non-Caucasian (Japanese) patients on chronic hemodialysis. All-cause and cardiovascular mortality was monitored prospectively during a period of 6 years. During the follow-up period, 42 of the 128 patients died; 19 of those patients died of CVD. Skin autofluorescence did not have a significant effect on all-cause mortality. However, age, carotid artery intima-media thickness (IMT), serum albumin, high-sensitivity C-reactive protein (hsCRP), skin autofluorescence and pre-existing CVD were significantly correlated with cardiovascular mortality. Multivariate Cox regression analysis showed skin autofluorescence (adjusted hazard ratio [HR] 3.97; 95% confidence interval [CI]1.67-9.43), serum albumin (adjusted HR 0.05; 95% CI 0.01-0.32), and hsCRP (adjusted HR 1.55; 95% CI 1.18-2.05) to be independent predictors of cardiovascular mortality. The present study suggests that skin autofluorescence is an independent predictor of cardiovascular mortality in non-Caucasian (Japanese) patients on chronic hemodialysis. © 2014 The Authors. Therapeutic Apheresis and Dialysis © 2014 International Society for Apheresis.

  2. Progress in developing a living human tissue-engineered tri-leaflet heart valve assembled from tissue produced by the self-assembly approach.

    Science.gov (United States)

    Dubé, Jean; Bourget, Jean-Michel; Gauvin, Robert; Lafrance, Hugues; Roberge, Charles J; Auger, François A; Germain, Lucie

    2014-08-01

    The aortic heart valve is constantly subjected to pulsatile flow and pressure gradients which, associated with cardiovascular risk factors and abnormal hemodynamics (i.e. altered wall shear stress), can cause stenosis and calcification of the leaflets and result in valve malfunction and impaired circulation. Available options for valve replacement include homograft, allogenic or xenogenic graft as well as the implantation of a mechanical valve. A tissue-engineered heart valve containing living autologous cells would represent an alternative option, particularly for pediatric patients, but still needs to be developed. The present study was designed to demonstrate the feasibility of using a living tissue sheet produced by the self-assembly method, to replace the bovine pericardium currently used for the reconstruction of a stented human heart valve. In this study, human fibroblasts were cultured in the presence of sodium ascorbate to produce tissue sheets. These sheets were superimposed to create a thick construct. Tissue pieces were cut from these constructs and assembled together on a stent, based on techniques used for commercially available replacement valves. Histology and transmission electron microscopy analysis showed that the fibroblasts were embedded in a dense extracellular matrix produced in vitro. The mechanical properties measured were consistent with the fact that the engineered tissue was resistant and could be cut, sutured and assembled on a wire frame typically used in bioprosthetic valve assembly. After a culture period in vitro, the construct was cohesive and did not disrupt or disassemble. The tissue engineered heart valve was stimulated in a pulsatile flow bioreactor and was able to sustain multiple duty cycles. This prototype of a tissue-engineered heart valve containing cells embedded in their own extracellular matrix and sewn on a wire frame has the potential to be strong enough to support physiological stress. The next step will be to test

  3. MRI of cardiovascular malformations

    Energy Technology Data Exchange (ETDEWEB)

    Kastler, Bruno [Centre Hospitalier Univ. Jean Minjoz, Besancon (France); Universite de Franche-Comte, Besancon (FR). Lab. I4S (Health, Innovation, Intervention, Imaging, Engineering); Centre Hospitalier Sherbrooke Univ., PQ (Canada). Dept. of Radiology

    2011-07-01

    MRI is a non-invasive and non-ionizing imaging modality that is perfectly suited for the diagnosis and follow-up of both pediatric and adult congenital heart disease. It provides a large field of view and has the unique ability to depict complex cardiac and vascular anatomy and to measure cardiac function and flow within one examination. MRI is the ideal complement to echocardiography whenever the information provided by the latter is limited. This book has been conceived as a self-teaching manual that will assist qualified radiologists, cardiologists, and pediatricians, as well as those in training. It is richly illustrated with numerous images and drawings that cover all usual and most unusual anomalies. The principal author, Professor Bruno Kastler, is head of radiology at Besancon University Hospital, France and is board certified in both radiology and cardiology. (orig.)

  4. 4D flow imaging with MRI

    Science.gov (United States)

    Stankovic, Zoran; Allen, Bradley D.; Garcia, Julio; Jarvis, Kelly B.

    2014-01-01

    Magnetic resonance imaging (MRI) has become an important tool for the clinical evaluation of patients with cardiovascular disease. Since its introduction in the late 1980s, 2-dimensional phase contrast MRI (2D PC-MRI) has become a routine part of standard-of-care cardiac MRI for the assessment of regional blood flow in the heart and great vessels. More recently, time-resolved PC-MRI with velocity encoding along all three flow directions and three-dimensional (3D) anatomic coverage (also termed ‘4D flow MRI’) has been developed and applied for the evaluation of cardiovascular hemodynamics in multiple regions of the human body. 4D flow MRI allows for the comprehensive evaluation of complex blood flow patterns by 3D blood flow visualization and flexible retrospective quantification of flow parameters. Recent technical developments, including the utilization of advanced parallel imaging techniques such as k-t GRAPPA, have resulted in reasonable overall scan times, e.g., 8-12 minutes for 4D flow MRI of the aorta and 10-20 minutes for whole heart coverage. As a result, the application of 4D flow MRI in a clinical setting has become more feasible, as documented by an increased number of recent reports on the utility of the technique for the assessment of cardiac and vascular hemodynamics in patient studies. A number of studies have demonstrated the potential of 4D flow MRI to provide an improved assessment of hemodynamics which might aid in the diagnosis and therapeutic management of cardiovascular diseases. The purpose of this review is to describe the methods used for 4D flow MRI acquisition, post-processing and data analysis. In addition, the article provides an overview of the clinical applications of 4D flow MRI and includes a review of applications in the heart, thoracic aorta and hepatic system. PMID:24834414

  5. The cardiovascular system after exercise.

    Science.gov (United States)

    Romero, Steven A; Minson, Christopher T; Halliwill, John R

    2017-04-01

    Recovery from exercise refers to the time period between the end of a bout of exercise and the subsequent return to a resting or recovered state. It also refers to specific physiological processes or states occurring after exercise that are distinct from the physiology of either the exercising or the resting states. In this context, recovery of the cardiovascular system after exercise occurs across a period of minutes to hours, during which many characteristics of the system, even how it is controlled, change over time. Some of these changes may be necessary for long-term adaptation to exercise training, yet some can lead to cardiovascular instability during recovery. Furthermore, some of these changes may provide insight into when the cardiovascular system has recovered from prior training and is physiologically ready for additional training stress. This review focuses on the most consistently observed hemodynamic adjustments and the underlying causes that drive cardiovascular recovery and will highlight how they differ following resistance and aerobic exercise. Primary emphasis will be placed on the hypotensive effect of aerobic and resistance exercise and associated mechanisms that have clinical relevance, but if left unchecked, can progress to symptomatic hypotension and syncope. Finally, we focus on the practical application of this information to strategies to maximize the benefits of cardiovascular recovery, or minimize the vulnerabilities of this state. We will explore appropriate field measures, and discuss to what extent these can guide an athlete's training. Copyright © 2017 the American Physiological Society.

  6. Vitamin D and Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Martin R. Grübler

    2013-07-01

    Full Text Available Vitamin D deficiency, as well as cardiovascular diseases (CVD and related risk factors are highly prevalent worldwide and frequently co-occur. Vitamin D has long been known to be an essential part of bone metabolism, although recent evidence suggests that vitamin D plays a key role in the pathophysiology of other diseases, including CVD, as well. In this review, we aim to summarize the most recent data on the involvement of vitamin D deficiency in the development of major cardiovascular risk factors: hypertension, obesity and dyslipidemia, type 2 diabetes, chronic kidney disease and endothelial dysfunction. In addition, we outline the most recent observational, as well as interventional data on the influence of vitamin D on CVD. Since it is still an unresolved issue whether vitamin D deficiency is causally involved in the pathogenesis of CVD, data from randomized controlled trials (RCTs designed to assess the impact of vitamin D supplementation on cardiovascular outcomes are awaited with anticipation. At present, we can only conclude that vitamin D deficiency is an independent cardiovascular risk factor, but whether vitamin D supplementation can significantly improve cardiovascular outcomes is still largely unknown.

  7. Cardiovascular consequences of childhood obesity.

    Science.gov (United States)

    McCrindle, Brian W

    2015-02-01

    Childhood and adolescent overweight and obesity is an important and increasingly prevalent public health problem in Canada and worldwide. High adiposity in youth is indicated in clinical practice by plotting body mass index on appropriate percentile charts normed for age and sex, although waist measures might be a further tool. High adiposity can lead to adiposopathy in youth, with associated increases in inflammation and oxidative stress, changes in adipokines, and endocrinopathy. This is manifest as cardiometabolic risk factors in similar patterns to those in noted in obese adults. Obesity and cardiometabolic risk factors have been shown to be associated with vascular changes indicative of early atherosclerosis, and ventricular hypertrophy, dilation, and dysfunction. These cardiovascular consequences are evident in youth, but childhood obesity is also predictive of similar consequences in adulthood. Childhood obesity and risk factors have been shown to track into adulthood and worsen in most individuals. The result is an exponential acceleration of atherosclerosis, which can be predicted to translate into an epidemic of premature cardiovascular disease and events. A change in paradigm is needed toward preventing and curing atherosclerosis and not just preventing cardiovascular disease. This would necessarily create an imperative for preventing and treating childhood obesity. Urgent attention, policy, and action are needed to avoid the enormous future social and health care costs associated with the cardiovascular consequences of obesity in youth. Copyright © 2015 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  8. PPARs and the Cardiovascular System

    Science.gov (United States)

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

    2009-01-01

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

  9. Cardiovascular Risk in Primary Hyperaldosteronism.

    Science.gov (United States)

    Prejbisz, A; Warchoł-Celińska, E; Lenders, J W M; Januszewicz, A

    2015-12-01

    After the first cases of primary aldosteronism were described and characterized by Conn, a substantial body of experimental and clinical evidence about the long-term effects of excess aldosterone on the cardiovascular system was gathered over the last 5 decades. The prevalence of primary aldosteronism varies considerably between different studies among hypertensive patients, depending on patient selection, the used diagnostic methods, and the severity of hypertension. Prevalence rates vary from 4.6 to 16.6% in those studies in which confirmatory tests to diagnose primary aldosteronism were used. There is also growing evidence indicating that prolonged exposure to elevated aldosterone concentrations is associated with target organ damage in the heart, kidney, and arterial wall, and high cardiovascular risk in patients with primary aldosteronism. Therefore, the aim of treatment should not be confined to BP normalization and hypokalemia correction, but rather should focus on restoring the deleterious effects of excess aldosterone on the cardiovascular system. Current evidence convincingly demonstrates that both surgical and medical treatment strategies beneficially affect cardiovascular outcomes and mortality in the long term. Further studies can be expected to provide better insight into the relationship between cardiovascular risk and complications and the genetic background of primary aldosteronism. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Sex differences in cardiovascular ageing.

    Science.gov (United States)

    Merz, Allison A; Cheng, Susan

    2016-06-01

    Despite recent progress in identifying and narrowing the gaps in cardiovascular outcomes between men and women, general understanding of how and why cardiovascular disease presentations differ between the sexes remains limited. Sex-specific patterns of cardiac and vascular ageing play an important role and, in fact, begin very early in life. Differences between the sexes in patterns of age-related cardiac remodelling are associated with the relatively greater prevalence in women than in men of heart failure with preserved ejection fraction. Similarly, sex variation in how vascular structure and function change with ageing contributes to differences between men and women in how coronary artery disease manifests typically or atypically over the adult life course. Both hormonal and non-hormonal factors underlie sex differences in cardiovascular ageing and the development of age-related disease. The midlife withdrawal of endogenous oestrogen appears to augment the age-related increase in cardiovascular risk seen in postmenopausal compared with premenopausal women. However, when compared with intrinsic biological differences between men and women that are present throughout life, this menopausal transition may not be as substantial an actor in determining cardiovascular outcomes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  11. Smokeless tobacco and cardiovascular risk.

    Science.gov (United States)

    Gupta, Ritesh; Gurm, Hitinder; Bartholomew, John R

    2004-09-27

    This article discusses the evolution of smokeless tobacco in the United States and interprets the available data on cardiovascular risk factors and cardiovascular mortality associated with its use. There has been a resurgence of smokeless tobacco use since 1970. Smokeless tobacco consistently produces levels of nicotine higher than those seen with smoking and causes similar sympathetic neural stimulation and acute cardiovascular effects. However, there is conflicting evidence from prospective and case-control studies about cardiovascular mortality or myocardial infarction caused by smokeless tobacco use. Smokeless tobacco use is also associated with oral cancers and high-risk behavior in adolescents. Although the evidence is not conclusive, the adverse cardiovascular effects of smokeless tobacco use are less than those caused by smoking but are more than those found in nonusers. It is advisable to counsel all current users of smokeless tobacco to quit. Behavioral counseling, sustained-release bupropion hydrochloride therapy, and nicotine replacement therapy may be safe therapeutic modalities for treatment of smokeless tobacco use.

  12. A definition of normovolaemia and consequences for cardiovascular control during orthostatic and environmental stress

    DEFF Research Database (Denmark)

    Truijen, Jasper; Bundgaard-Nielsen, Morten; van Lieshout, Johannes J

    2010-01-01

    stress including bed rest/microgravity, exercise and training, thermal loading, illness, and trauma/haemorrhage is likely to restrict venous return and Q. Consequently the cardiovascular responses are determined primarily by their effect on the central blood volume. Thus during environmental stress, flow......The Frank-Starling mechanism describes the relationship between stroke volume and preload to the heart, or the volume of blood that is available to the heart--the central blood volume. Understanding the role of the central blood volume for cardiovascular control has been complicated by the fact...... redistribution becomes dependent on sympathetic activation affecting not only skin and splanchnic blood flow, but also flow to skeletal muscles and the brain. This review addresses the hypothesis that deviations from normovolaemia significantly influence these cardiovascular responses....

  13. Habituation and conditioning of the defense reactions and their cardiovascular components in cats and dogs.

    Science.gov (United States)

    Martin, J; Sutherland, C J; Zbrozyna, A W

    1976-09-03

    Cardiovascular and behavioural responses elicited by novel, noxious or aversive stimuli have been studied in dogs and cats. Hindlimb blood flow, heart rate and arterial blood pressure increased in dogs when an orienting response was elicited by a novel stimulus (a sound). Similar cardiovascular responses occurred in dogs to mild noxious stimulus and in cats displaying a threatening posture when confronted by a dog. The cardiovascular components of the orienting response to a sound habituated with repetition of the sound. In two dogs however sensitization (increase) of the response occurred with reped by repetition of the confrontations: the vasodilation in the muscles waned and eventually was replaced by vasoconstriction while the cardiac acceleration and pressor response persisted. The threatening response was the most persistent. The modification of the behavioural and cardiovascular aspect of the response was not developing in parallel. The cardiovascular pattern was altered before any apparent changes of the behavioural pattern occurred. The cardiovascular responses of the noxious stimulus in dogs and cardiovascular components of the defence reaction in cats were readily conditioned to a sound. The possible role of the modification of the cardiovascular pattern in defence reactions in pathogenesis of hypertension is discussed.

  14. Flow Cytometry in Pediatric Malignancies.

    Science.gov (United States)

    Handoo, Anil; Dadu, Tina

    2018-01-15

    The utility of flow cytometry as a useful diagnostic modality for the assessment of hematopoietic neoplasms has been established beyond doubt. In fact, it is now an integral part of the diagnosis and classification of various diseases like leukemias and lymphomas along with molecular studies and cytogenetics. Prognostication and disease monitoring by flow cytometry is also being recognized increasingly as one of the important fortes. This is evident by the number of articles in the published in literature on the minimal residual disease detection by flow cytometry especially in the last decade or so. To add to this, ever growing list of utilities in hematopoietic malignancies, many non-hematopoietic neoplasms can also be analyzed by flow cytometry. The examples include fluid specimens from serous cavity effusions and samples from solid tissues like lymph nodes, reticulo-endothelial tissue, central nervous system tissue, etc. Flow cytometry technique provides a unique blend of rapidity, high sensitivity and specificity compared to cyto-morphology and conventional immunohistochemical staining. It is also remarkable for simultaneous analysis of more than one marker on the cells. Evaluation of limited samples such as cerebrospinal fluid or fine needle aspiration samples makes Flow cytometry a valuable tool. DNA ploidy analysis and assessment of pediatric non-hematopoietic neoplasms by Flow cytometry has envisaged the utility vista of this technique. This review is aimed at providing an insight into the applications of flow cytometry in pediatric malignancies.

  15. Flow visualization

    CERN Document Server

    Merzkirch, Wolfgang

    1974-01-01

    Flow Visualization describes the most widely used methods for visualizing flows. Flow visualization evaluates certain properties of a flow field directly accessible to visual perception. Organized into five chapters, this book first presents the methods that create a visible flow pattern that could be investigated by visual inspection, such as simple dye and density-sensitive visualization methods. It then deals with the application of electron beams and streaming birefringence. Optical methods for compressible flows, hydraulic analogy, and high-speed photography are discussed in other cha

  16. Cardiovascular Disease and Thyroid Function

    DEFF Research Database (Denmark)

    Faber, Jens; Selmer, Christian

    2014-01-01

    Thyroid function has a profound effect on the heart, and both all-cause and cardiovascular mortality rates are increased in hyperthyroidism. New-onset atrial fibrillation carries a prolonged risk for the development of hyperthyroidism, suggesting altered availability of thyroid hormones at the ce......Thyroid function has a profound effect on the heart, and both all-cause and cardiovascular mortality rates are increased in hyperthyroidism. New-onset atrial fibrillation carries a prolonged risk for the development of hyperthyroidism, suggesting altered availability of thyroid hormones...... at the cellular level. Subclinical hyperthyroidism is associated with increased left ventricular mass of the heart, which reverts after obtaining euthyroidism. Mortality and risk of major cardiovascular events are increased. Subclinical hypothyroidism is also associated with subtle changes in the heart, e.g. its...

  17. Multimodality cardiovascular molecular imaging technology.

    Science.gov (United States)

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

    2010-05-01

    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.

  18. Educational inequality in cardiovascular diseases

    DEFF Research Database (Denmark)

    Søndergaard, Grethe; Dalton, Susanne Oksbjerg; Mortensen, Laust Hvas

    2018-01-01

    AIMS: Educational inequality in diseases in the circulatory system (here termed cardiovascular disease) is well documented but may be confounded by early life factors. The aim of this observational study was to examine whether the associations between education and all cardiovascular diseases...... in conventional cohort and within-sibship analyses in which the association was examined within siblings discordant on education. Assuming that attenuation of associations in the within-sibship as compared with the cohort analyses would indicate confounding from factors shared within families. RESULTS: A lower...... educational status was associated with a higher risk of cardiovascular disease, ischaemic heart disease and stroke. All associations attenuated in the within-sibship analyses, in particular in the analyses on ischaemic heart disease before age 45 years. For instance, in the cohort analyses, the hazard rate...

  19. Cognitive dysfunction after cardiovascular surgery

    DEFF Research Database (Denmark)

    Funder, K S; Steinmetz, J; Rasmussen, L S

    2009-01-01

    This review describes the incidence, risk factors, and long-term consequences of cognitive dysfunction after cardiovascular surgery. Postoperative cognitive dysfunction (POCD) is increasingly being recognized as an important complication, especially in the elderly. A highly sensitive neuropsychol......This review describes the incidence, risk factors, and long-term consequences of cognitive dysfunction after cardiovascular surgery. Postoperative cognitive dysfunction (POCD) is increasingly being recognized as an important complication, especially in the elderly. A highly sensitive...... neuropsychological test battery must be used to detect POCD and a well-matched control group is very useful for the analysis and interpretation of the test RESULTS: Cardiovascular surgery is associated with a high incidence of POCD. Cardiopulmonary bypass was thought to explain this difference, but randomized...

  20. MARCADORES CARDIACOS Y RIESGO CARDIOVASCULAR

    Directory of Open Access Journals (Sweden)

    Dr. David Doron R.

    2015-03-01

    La mortalidad por causa cardiovascular es la primera causa de muerte en el mundo desarrollado y tambiècn en Chile, por lo que los esfuerzos de identificación acuciosa y de correcta clasificación de riesgo de los individuos o población permiten una eficiente focalización de los esfuerzos por disminuir los eventos cardiovasculares. En este artículo se revisan distintos marcadores cardiacos (proteína C reactiva ultra sensible, score calcio coronario, pècptido natriurèctico y troponina ultrasensible y las evidencias que apoyan o desalientan su uso para una adecuada evaluación de riesgo cardiovascular.

  1. SLEEP DEPRIVATION AND CARDIOVASCULAR RISK

    Directory of Open Access Journals (Sweden)

    V. А. Vizir

    2013-06-01

    Full Text Available In a review article extensively discusses the relationship between sleep duration and cardiovascular diseases. Sleep loss is a common condition in developed countries, with evidence showing that people in Western countries are sleeping on average only 6.8 hour per night, 1.5 hour less than a century ago. Although the effect of sleep deprivation on the human body is not completely unexplained, recent epidemiological studies have revealed relationships between sleep deprivation and arterial hypertension, coronary heart disease and diabetes mellitus. Increased sympathetic nervous system activity and changes in melatonin secretion are considered as the main pathophysiological mechanisms involved in the development and progression of cardiovascular disease in patients with insufficient duration of nighttime sleep. Adequate sleep duration may be important for preventing cardiovascular diseases in modern society.

  2. SIRT1 in cardiovascular aging.

    Science.gov (United States)

    Luo, Xin-Yuan; Qu, Shun-Lin; Tang, Zhi-Han; Zhang, Yuan; Liu, Mi-Hua; Peng, Juan; Tang, Hui; Yu, Kang-Lun; Zhang, Chi; Ren, Zhong; Jiang, Zhi-Sheng

    2014-11-01

    Cardiovascular disease (CVD) is the leading cause of death worldwide, with aging as the key independent risk factor. Effective interventions are necessary to delay aging. Sirtuin1 (SIRT1), a NAD(+)-dependent histone deacetylase, is closely related to lifespan extension. SIRT1 exerts beneficial effects on aging and age-related diseases, such as atherosclerosis. In this review, we summarize the current knowledge on the functions of SIRT1 in cardiovascular aging, focusing on the underlying molecular mechanisms, including inhibition of oxidative stress and inflammation, and induction of autophagy. We also demonstrate that moderate up-regulation or activation of SIRT1 in cardiovascular aging and age-related CVD may confer important application values. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Cardiovascular effects of air pollution.

    Science.gov (United States)

    Bourdrel, Thomas; Bind, Marie-Abèle; Béjot, Yannick; Morel, Olivier; Argacha, Jean-François

    2017-11-01

    Air pollution is composed of particulate matter (PM) and gaseous pollutants, such as nitrogen dioxide and ozone. PM is classified according to size into coarse particles (PM 10 ), fine particles (PM 2.5 ) and ultrafine particles. We aim to provide an original review of the scientific evidence from epidemiological and experimental studies examining the cardiovascular effects of outdoor air pollution. Pooled epidemiological studies reported that a 10μg/m 3 increase in long-term exposure to PM 2.5 was associated with an 11% increase in cardiovascular mortality. Increased cardiovascular mortality was also related to long-term and short-term exposure to nitrogen dioxide. Exposure to air pollution and road traffic was associated with an increased risk of arteriosclerosis, as shown by premature aortic and coronary calcification. Short-term increases in air pollution were associated with an increased risk of myocardial infarction, stroke and acute heart failure. The risk was increased even when pollutant concentrations were below European standards. Reinforcing the evidence from epidemiological studies, numerous experimental studies demonstrated that air pollution promotes a systemic vascular oxidative stress reaction. Radical oxygen species induce endothelial dysfunction, monocyte activation and some proatherogenic changes in lipoproteins, which initiate plaque formation. Furthermore, air pollution favours thrombus formation, because of an increase in coagulation factors and platelet activation. Experimental studies also indicate that some pollutants have more harmful cardiovascular effects, such as combustion-derived PM 2.5 and ultrafine particles. Air pollution is a major contributor to cardiovascular diseases. Promotion of safer air quality appears to be a new challenge in cardiovascular disease prevention. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  4. Maladaptive immune and inflammatory pathways lead to cardiovascular insulin resistance

    Science.gov (United States)

    Aroor, Annayya R.; McKarns, Susan; DeMarco, Vincent G.; Guanghong, Jia; Sowers, James R.

    2013-01-01

    Insulin resistance is a hallmark of obesity, the cardiorenal metabolic syndrome and type 2 diabetes mellitus (T2DM). The progression of insulin resistance increases the risk for cardiovascular disease (CVD). The significance of insulin resistance is underscored by the alarming rise in the prevalence of obesity and its associated comorbidities in the Unites States and worldwide over the last 40-50 years. The incidence of obesity is also on the rise in adolescents. Furthermore, premenopausal women have lower CVD risk compared to men, but this protection is lost in the setting of obesity and insulin resistance. Although systemic and cardiovascular insulin resistance are associated with impaired insulin metabolic signaling and cardiovascular dysfunction, the mechanisms underlying insulin resistance and cardiovascular dysfunction remain poorly understood. Recent studies show that insulin resistance in obesity and diabetes is linked to a metabolic inflammatory response, a state of systemic and tissue specific chronic low grade inflammation. Evidence is also emerging that there is polarization of macrophages and lymphocytes towards a pro-inflammatory phenotype that contribute to progression of insulin resistance in obesity, cardiorenal metabolic syndrome and diabetes. In this review, we provide new insights into factors, such as, the renin-angiotensin-aldosterone system, sympathetic activation and incretin modulators (e.g., DPP-4) and immune responses that mediate this inflammatory state in obesity and other conditions characterized by insulin resistance. PMID:23932846

  5. YKL-40 - an emerging biomarker in cardiovascular disease and diabetes

    Directory of Open Access Journals (Sweden)

    Rathcke Camilla

    2009-01-01

    Full Text Available Abstract Several inflammatory cytokines are involved in vascular inflammation resulting in endothelial dysfunction which is the earliest event in the atherosclerotic process leading to manifest cardiovascular disease. YKL-40 is an inflammatory glycoprotein involved in endothelial dysfunction by promoting chemotaxis, cell attachment and migration, reorganization and tissue remodelling as a response to endothelial damage. YKL-40 protein expression is seen in macrophages and smooth muscle cells in atherosclerotic plaques with the highest expression seen in macrophages in the early lesion of atherosclerosis. Several studies demonstrate, that elevated serum YKL-levels are independently associated with the presence and extent of coronary artery disease and even higher YKL-40 levels are documented in patients with myocardial infarction. Moreover, elevated serum YKL-40 levels have also been found to be associated with all-cause as well as cardiovascular mortality. Finally, YKL-40 levels are elevated both in patients with type 1 and type 2 diabetes, known to be at high risk for the development of cardiovascular diseases, when compared to non-diabetic persons. A positive association between elevated circulating YKL-40 levels and increasing levels of albuminuria have been described in patients with type 1 diabetes indicating a role of YKL-40 in the progressing vascular damage resulting in microvascular disease. This review describes the present knowledge about YKL-40 and discusses its relation to endothelial dysfunction, atherosclerosis, cardiovascular disease and diabetes and look ahead on future perspectives of YKL-40 research.

  6. Maladaptive immune and inflammatory pathways lead to cardiovascular insulin resistance.

    Science.gov (United States)

    Aroor, Annayya R; McKarns, Susan; Demarco, Vincent G; Jia, Guanghong; Sowers, James R

    2013-11-01

    Insulin resistance is a hallmark of obesity, the cardiorenal metabolic syndrome and type 2 diabetes mellitus (T2DM). The progression of insulin resistance increases the risk for cardiovascular disease (CVD). The significance of insulin resistance is underscored by the alarming rise in the prevalence of obesity and its associated comorbidities in the Unites States and worldwide over the last 40-50 years. The incidence of obesity is also on the rise in adolescents. Furthermore, premenopausal women have lower CVD risk compared to men, but this protection is lost in the setting of obesity and insulin resistance. Although systemic and cardiovascular insulin resistance is associated with impaired insulin metabolic signaling and cardiovascular dysfunction, the mechanisms underlying insulin resistance and cardiovascular dysfunction remain poorly understood. Recent studies show that insulin resistance in obesity and diabetes is linked to a metabolic inflammatory response, a state of systemic and tissue specific chronic low grade inflammation. Evidence is also emerging that there is polarization of macrophages and lymphocytes towards a pro-inflammatory phenotype that contributes to progression of insulin resistance in obesity, cardiorenal metabolic syndrome and diabetes. In this review, we provide new insights into factors, such as, the renin-angiotensin-aldosterone system, sympathetic activation and incretin modulators (e.g., DPP-4) and immune responses that mediate this inflammatory state in obesity and other conditions characterized by insulin resistance. © 2013.

  7. Psychosocial perspectives in cardiovascular disease

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; von Känel, Roland; Tully, Phillip J

    2017-01-01

    Adaptation to living with cardiovascular disease may differ from patient to patient and is influenced not only by disease severity and limitations incurred by the disease but also by socioeconomic factors (e.g. health literacy), the patients' psychological make-up and susceptibility to distress. Co......-morbid depression and/or anxiety is prevalent in 20% of patients with cardiovascular disease, which may be either transient or chronic. Distress, such as depression, reduces adherence, serves as a barrier to behaviour change and the adoption of a healthy lifestyle, and increases the risk that patients drop out...

  8. Cardiovascular disease after cancer therapy

    DEFF Research Database (Denmark)

    Aleman, Berthe M P; Moser, Elizabeth C; Nuver, Janine

    2014-01-01

    Improvements in treatment and earlier diagnosis have both contributed to increased survival for many cancer patients. Unfortunately, many treatments carry a risk of late effects including cardiovascular diseases (CVDs), possibly leading to significant morbidity and mortality. In this paper we......, and the mechanisms involved, as well as the extent to which treatments may increase CVD indirectly by increasing cardiovascular risk factors is also important. Systematic collection of data relating treatment details to late effects is needed, and great care is needed to obtain valid and generalisable results...

  9. Cardiovascular disease incidence and survival

    DEFF Research Database (Denmark)

    Byberg, Stine; Agyemang, Charles; Zwisler, Ann-Dorthe

    2016-01-01

    Studies on cardiovascular disease (CVD) incidence and survival show varying results between different ethnic groups. Our aim was to add a new dimension by exploring the role of migrant status in combination with ethnic background on incidence of-and survival from-CVD and more specifically acute...... of some types of cardiovascular disease compared to Danish-born. Family-reunified migrants on the other hand had lower rates of CVD. All migrants had better survival than Danish-born indicating that migrants may not always be disadvantaged in health....

  10. Cardiovascular manifestations of subarachnoid haemorrhage

    Directory of Open Access Journals (Sweden)

    Sethuraman Manikandan

    2017-01-01

    Full Text Available Subarachnoid haemorrhage (SAH is one of the devastating conditions, especially the aneurysmal bleed which has high mortality as well as morbidity. The mortality and morbidity caused by SAH have been recognised to be caused by both neurological and systemic causes. The alterations in systemic and other organ damage could cause death in up to 40% of SAH patients. Among the systemic manifestations, cardiovascular and respiratory complications increase hospitalisation and worsen the outcome. The main pathophysiological mechanism is the increased sympathetic activation causing myocardial necrosis. Various cardiovascular manifestations range from electrocardiogram changes to myocardial ischaemia, cardiac failure and arrhythmias. This review deals with the cardiac manifestations in SAH patients.

  11. Cardiovascular investigations of airline pilots with excessive cardiovascular risk.

    Science.gov (United States)

    Wirawan, I Made Ady; Aldington, Sarah; Griffiths, Robin F; Ellis, Chris J; Larsen, Peter D

    2013-06-01

    This study examined the prevalence of airline pilots who have an excessive cardiovascular disease (CVD) risk score according to the New Zealand Guideline Group (NZGG) Framingham-based Risk Chart and describes their cardiovascular risk assessment and investigations. A cross-sectional study was performed among 856 pilots employed in an Oceania based airline. Pilots with elevated CVD risk that had been previously evaluated at various times over the previous 19 yr were reviewed retrospectively from the airline's medical records, and the subsequent cardiovascular investigations were then described. There were 30 (3.5%) pilots who were found to have 5-yr CVD risk score of 10-15% or higher. Of the 29 pilots who had complete cardiac investigations data, 26 pilots underwent exercise electrocardiography (ECG), 2 pilots progressed directly to coronary angiograms and 1 pilot with abnormal echocardiogram was not examined further. Of the 26 pilots, 7 had positive or borderline exercise tests, all of whom subsequently had angiograms. One patient with a negative exercise test also had a coronary angiogram. Of the 9 patients who had coronary angiograms as a consequence of screening, 5 had significant disease that required treatment and 4 had either trivial disease or normal coronary arteries. The current approach to investigate excessive cardiovascular risk in pilots relies heavily on exercise electrocardiograms as a diagnostic test, and may not be optimal either to detect disease or to protect pilots from unnecessary invasive procedures. A more comprehensive and accurate cardiac investigation algorithm to assess excessive CVD risk in pilots is required.

  12. Impact of hydrotherapy on skin blood flow: How much is due to moisture and how much is due to heat?

    Science.gov (United States)

    Petrofsky, Jerrold; Gunda, Shashi; Raju, Chinna; Bains, Gurinder S; Bogseth, Michael C; Focil, Nicholas; Sirichotiratana, Melissa; Hashemi, Vahideh; Vallabhaneni, Pratima; Kim, Yumi; Madani, Piyush; Coords, Heather; McClurg, Maureen; Lohman, Everett

    2010-02-01

    Hydrotherapy and whirlpool are used to increase skin blood flow and warm tissue. However, recent evidence seems to show that part of the increase in skin blood flow is not due to the warmth itself but due to the moisture content of the heat. Therefore, two series of experiments were accomplished on 10 subjects with an average age of 24.2 +/- 9.7 years and free of diabetes and cardiovascular disease. Subjects sat in a 37 degrees C hydrotherapy pool under two conditions: one in which a thin membrane protecting their skin from moisture while their arm was submerged in water and the second where their arm was allowed to be exposed to the water for 15 minutes. During this period of time, skin and body temperature were measured as well as skin blood flow by a Laser Doppler Imager. The results of the experiments showed that the vapor barrier blocked any change in skin moisture content during submersion in water, and while skin temperature was the same as during exposure to the water, the blood flow with the arm exposed to water increased from 101.1 +/- 10.4 flux to 224.9 +/- 18.2 flux, whereas blood flow increased to only 118.7 +/- 11.4 flux if the moisture of the water was blocked. Thus, a substantial portion of the increase in skin blood flow associated with warm water therapy is probably associated with moisturizing of the skin rather than the heat itself.

  13. Cardiovascular Imaging Techniques in Systemic Rheumatic Diseases

    Directory of Open Access Journals (Sweden)

    Fabiola Atzeni

    2018-02-01

    Full Text Available The risk of cardiovascular (CV events and mortality is significantly higher in patients with systemic rheumatic diseases than in the general population. Although CV involvement in such patients is highly heterogeneous and may affect various structures of the heart, it can now be diagnosed earlier and promptly treated. Various types of assessments are employed for the evaluation of CV risk such as transthoracic or transesophageal echocardiography, magnetic resonance imaging (MRI, and computed tomography (CT to investigate valve abnormalities, pericardial disease, and ventricular wall motion defects. The diameter of coronary arteries can be assessed using invasive quantitative coronarography or intravascular ultrasound, and coronary flow reserve can be assessed using non-invasive transesophageal or transthoracic ultrasonography (US, MRI, CT, or positron emission tomography (PET after endothelium-dependent vasodilation. Finally, peripheral circulation can be measured invasively using strain-gauge plethysmography in an arm after the arterial infusion of an endothelium-dependent vasodilator or non-invasively by means of US or MRI measurements of flow-mediated vasodilation of the brachial artery. All of the above are reliable methods of investigating CV involvement, but more recently, introduced use of speckle tracking echocardiography and 3-dimensional US are diagnostically more accurate.

  14. Expanding application of the Wiggers diagram to teach cardiovascular physiology

    Science.gov (United States)

    Wang, Jiun-Jr

    2014-01-01

    Dr. Carl Wiggers' careful observations have provided a meaningful resource for students to learn how the heart works. Throughout the many years from his initial reports, the Wiggers diagram has been used, in various degrees of complexity, as a fundamental tool for cardiovascular instruction. Often, the various electrical and mechanical plots are the novice learner's first exposure to simulated data. As the various temporal relationships throughout a heartbeat could simply be memorized, the challenge for the cardiovascular instructor is to engage the learner so the underlying mechanisms governing the changing electrical and mechanical events are truly understood. Based on experience, we suggest some additions to the Wiggers diagram that are not commonly used to enhance cardiovascular pedagogy. For example, these additions could be, but are not limited to, introducing the concept of energy waves and their role in influencing pressure and flow in health and disease. Also, integrating concepts of exercise physiology, and the differences in cardiac function and hemodynamics between an elite athlete and normal subject, can have a profound impact on student engagement. In describing the relationship between electrical and mechanical events, the instructor may find the introduction of premature ventricular contractions as a useful tool to further understanding of this important principle. It is our hope that these examples can aid cardiovascular instructors to engage their learners and promote fundamental understanding at the expense of simple memorization. PMID:24913453

  15. The choice of cryopreservation method affects immune compatibility of human cardiovascular matrices.

    Science.gov (United States)

    Schneider, Maria; Stamm, Christof; Brockbank, Kelvin G M; Stock, Ulrich A; Seifert, Martina

    2017-12-05

    Conventional frozen cryopreservation (CFC) is currently the gold standard for cardiovascular allograft preservation. However, inflammation and structural deterioration limit transplant durability. Ice-free cryopreservation (IFC) already demonstrated matrix structure preservation combined with attenuated immune responses. In this study, we aim to explore the mechanisms of this diminished immunogenicity in vitro. First, we characterized factors released by human aortic tissue after CFC and IFC. Secondly, we analyzed co-cultures with human peripheral blood mononuclear cells, purified monocytes, T cells and monocyte-derived macrophages to examine functional immune effects triggered by the tissue or released cues. IFC tissue exhibited significantly lower metabolic activity and release of pro-inflammatory cytokines than CFC tissue, but surprisingly, more active transforming growth factor β. Due to reduced cytokine release by IFC tissue, less monocyte and T cell migration was detected in a chemotaxis system. Moreover, only cues from CFC tissue but not from IFC tissue