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Sample records for tissues cardiovascular flows

  1. Detection of hydroxyapatite in calcified cardiovascular tissues.

    Science.gov (United States)

    Lee, Jae Sam; Morrisett, Joel D; Tung, Ching-Hsuan

    2012-10-01

    The objective of this study is to develop a method for selective detection of the calcific (hydroxyapatite) component in human aortic smooth muscle cells in vitro and in calcified cardiovascular tissues ex vivo. This method uses a novel optical molecular imaging contrast dye, Cy-HABP-19, to target calcified cells and tissues. A peptide that mimics the binding affinity of osteocalcin was used to label hydroxyapatite in vitro and ex vivo. Morphological changes in vascular smooth muscle cells were evaluated at an early stage of the mineralization process induced by extrinsic stimuli, osteogenic factors and a magnetic suspension cell culture. Hydroxyapatite components were detected in monolayers of these cells in the presence of osteogenic factors and a magnetic suspension environment. Atherosclerotic plaque contains multiple components including lipidic, fibrotic, thrombotic, and calcific materials. Using optical imaging and the Cy-HABP-19 molecular imaging probe, we demonstrated that hydroxyapatite components could be selectively distinguished from various calcium salts in human aortic smooth muscle cells in vitro and in calcified cardiovascular tissues, carotid endarterectomy samples and aortic valves, ex vivo. Hydroxyapatite deposits in cardiovascular tissues were selectively detected in the early stage of the calcification process using our Cy-HABP-19 probe. This new probe makes it possible to study the earliest events associated with vascular hydroxyapatite deposition at the cellular and molecular levels. This target-selective molecular imaging probe approach holds high potential for revealing early pathophysiological changes, leading to progression, regression, or stabilization of cardiovascular diseases. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  2. 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.

  3. 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.

  4. 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

  5. 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

  6. Modeling collagen remodeling in tissue engineered cardiovascular tissues

    NARCIS (Netherlands)

    Soares, A.L.F.

    2012-01-01

    Commonly, heart valve replacements consist of non-living materials lacking the ability to grow, repair and remodel. Tissue engineering (TE) offers a promising alternative to these replacement strategies since it can overcome its disadvantages. The technique aims to create an autologous living tissue

  7. Human prenatal progenitors for pediatric cardiovascular tissue engineering

    NARCIS (Netherlands)

    Schmidt, D.

    2007-01-01

    Pediatric cardiovascular tissue engineering is a promising strategy to overcome the lack of autologous, growing replacements for the early repair of congenital malformations in order to prevent secondary damage to the immature heart. Therefore, cells should be harvested during pregnancy as soon as

  8. 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.

  9. 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)

  10. 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...

  11. 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

  12. Tissue Motion and Assembly During Early Cardiovascular Morphogenesis

    Science.gov (United States)

    Rongish, Brenda

    2010-03-01

    Conventional dogma in the field of cardiovascular developmental biology suggests that cardiac precursor cells migrate to the embryonic midline to form a tubular heart. These progenitors are believed to move relative to their extracellular matrix (ECM); responding to stimulatory and inhibitory cues in their environment. The tubular heart that is formed by 30 hours post fertilization is comprised of two concentric layers: the muscular myocardium and the endothelial-like endocardium, which are separated by a thick layer of ECM believed to be secreted predominantly by the myocardial cells. Here we describe the origin and motility of fluorescently tagged endocardial precursors in transgenic (Tie1-YFP) quail embryos (R. Lansford, Caltech) using epifluorescence time-lapse imaging. To visualize the environment of migrating endocardial progenitors, we labeled two ECM components, fibronectin and fibrillin-2, via in vivo microinjection of fluorochrome-conjugated monoclonal antibodies. Dynamic imaging was performed at stages encompassing tubular heart assembly and early looping. We established the motion of endocardial precursor cells and presumptive cardiac ECM fibrils using both object tracking and particle image velocimetry (image cross correlation). We determined the relative importance of directed cell autonomous motility versus passive tissue movements in endocardial morphogenesis. The data show presumptive endocardial cells and cardiac ECM fibrils are swept passively into the anterior and posterior poles of the elongating tubular heart. These quantitative data indicate the contribution of cell autonomous motility displayed by endocardial precursors is limited. Thus, tissue motion drives most of the cell displacements during endocardial morphogenesis.

  13. 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.

  14. Connective Tissue Disorders and Cardiovascular Complications: The indomitable role of Transforming Growth Factor-beta signaling

    Science.gov (United States)

    Wheeler, Jason B.; Ikonomidis, John S.; Jones, Jeffrey A.

    2015-01-01

    Marfan Syndrome (MFS) and Loeys-Dietz Syndrome (LDS) represent heritable connective tissue disorders that cosegregate with a similar pattern of cardiovascular defects (thoracic aortic aneurysm, mitral valve prolapse/regurgitation, and aortic dilatation with regurgitation). This pattern of cardiovascular defects appears to be expressed along a spectrum of severity in many heritable connective tissue disorders and raises suspicion of a relationship between the normal development of connective tissues and the cardiovascular system. Given the evidence of increased transforming growth factor-beta (TGF-β) signaling in MFS and LDS, this signaling pathway may represent the common link in this relationship. To further explore this hypothetical link, this chapter will review the TGF-β signaling pathway, heritable connective tissue syndromes related to TGF-β receptor (TGFBR) mutations, and discuss the pathogenic contribution of TGF-β to these syndromes with a primary focus on the cardiovascular system. PMID:24443024

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

    NARCIS (Netherlands)

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

    2015-01-01

    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

  16. 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...

  17. 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.

  18. Cardiovascular magnetic resonance frontiers: Tissue characterisation with mapping

    OpenAIRE

    Schofield, R.; Bhuva, A.; Manacho, K.; Moon, J. C.

    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 ...

  19. 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...... vasoconstriction with pronounced flow reduction. These two reactions may be important for local regulation of blood flow in subcutaneous tissue during orthostatic changes in arterial and venous pressure. It is concluded that the response in adipose tissue to changes in arterial pressure (autoregulation), venous...

  20. Nano-analytical electron microscopy reveals fundamental insights into human cardiovascular tissue calcification

    Science.gov (United States)

    Bertazzo, Sergio; Gentleman, Eileen; Cloyd, Kristy L.; Chester, Adrian H.; Yacoub, Magdi H.; Stevens, Molly M.

    2013-06-01

    The accumulation of calcified material in cardiovascular tissue is thought to involve cytochemical, extracellular matrix and systemic signals; however, its precise composition and nanoscale architecture remain largely unexplored. Using nano-analytical electron microscopy techniques, we examined valves, aortae and coronary arteries from patients with and without calcific cardiovascular disease and detected spherical calcium phosphate particles, regardless of the presence of calcific lesions. We also examined lesions after sectioning with a focused ion beam and found that the spherical particles are composed of highly crystalline hydroxyapatite that crystallographically and structurally differs from bone mineral. Taken together, these data suggest that mineralized spherical particles may play a fundamental role in calcific lesion formation. Their ubiquitous presence in varied cardiovascular tissues and from patients with a spectrum of diseases further suggests that lesion formation may follow a common process. Indeed, applying materials science techniques to ectopic and orthotopic calcification has great potential to lend critical insights into pathophysiological processes underlying calcific cardiovascular disease.

  1. 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.

  2. 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

  3. Modeling and remodeling of the collagen architecture in cardiovascular tissues

    NARCIS (Netherlands)

    Driessen, N.J.B.

    2006-01-01

    Heart valve replacement by a mechanical or biological prosthesis represents a common surgical therapy for end-stage valvular heart diseases. A critical drawback of these prostheses is the inability to grow, repair and remodel in response to changes in the tissue’s environment. Tissue engineering

  4. Perivascular adipose tissue: role in the pathogenesis of obesity, type 2 diabetes mellitus and cardiovascular pathology.

    Directory of Open Access Journals (Sweden)

    Tat'yana Ivanovna Romantsova

    2015-09-01

    Full Text Available Perivascular adipose tissue is a part of blood vessel wall, regulating endovascular homeostasis, endothelial and smooth muscle cells functioning. Under physiological conditions, perivascular tissue provides beneficial anticontractile effect, though undergoes structural and functional changes in obesity, atherosclerosis and diabetes mellitus type2.Collected data suggest the possible key role of perivascular adipose tissue in the pathogenesis of these diseases. Perivascular tissue has been determined as an independent cardiovascular risk factor, regardless of visceral obesity. General mechanisms include a local low-grade inflammation, oxidative stress, tissue renin-angiotensin-aldosterone system activation, paracrine and metabolic alterations. Properties of perivascular adipose tissue depend on the certain type of adipocytes it contains. Brown adipocytes are well known for their metabolic preferences, however it has been shown recently that brown perivascular tissue can contribute to dyslipidemia under some conditions.  The aim of this review is to discuss the current literature understanding of perivascular adipose tissue specifics, changes in its activity, secretory and genetic profilein a course of the most common non-infectious diseases development, as well as molecular mechanisms of its functioning. We also discuss perspectives of target interventions using metabolic pathways and genes of perivascular tissue, for the effective prevention of obesity, diabetes mellitus type2 and cardiovascular diseases.

  5. 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

  6. 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

  7. Water hardness and cardiovascular disease. Elements in water and human tissues

    Energy Technology Data Exchange (ETDEWEB)

    Sharrett, A R

    1977-05-01

    The hypothesis that the hardness of drinking water has a causal role in the development of cardiovascular disease will be strengthened if it can be demonstrated that elements in drinking water find their way into human tissues in significant amounts. For biologically important metals, the evidence is reviewed for a relationship of tissue levels to levels in drinking water. Hard water can contribute significantly to daily magnesium intake. Residents of hard-water areas may have raised levels of magnesium in coronary arteries, bone, and myocardial tissue. Lead levels in bone and in blood have been shown to be elevated in individuals living in homes with lead plumbing and soft water. Cadmium intake from water is probably small compared to that from other sources, and there is no convincing evidence of alteration in human tissue levels via drinking water cadmium. Human zinc and copper tissue levels are of interest but have not been adequately studied in relation to drinking water levels.

  8. 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.

  9. Increasing blood flow to exercising muscle attenuates systemic cardiovascular responses during dynamic exercise in humans.

    Science.gov (United States)

    Ichinose, Masashi; Ichinose-Kuwahara, Tomoko; Kondo, Narihiko; Nishiyasu, Takeshi

    2015-11-15

    Reducing blood flow to working muscles during dynamic exercise causes metabolites to accumulate within the active muscles and evokes systemic pressor responses. Whether a similar cardiovascular response is elicited with normal blood flow to exercising muscles during dynamic exercise remains unknown, however. To address that issue, we tested whether cardiovascular responses are affected by increases in blood flow to active muscles. Thirteen healthy subjects performed dynamic plantarflexion exercise for 12 min at 20%, 40%, and 60% of peak workload (EX20, EX40, and EX60) with their lower thigh enclosed in a negative pressure box. Under control conditions, the box pressure was the same as the ambient air pressure. Under negative pressure conditions, beginning 3 min after the start of the exercise, the box pressure was decreased by 20, 45, and then 70 mmHg in stepwise fashion with 3-min step durations. During EX20, the negative pressure had no effect on blood flow or the cardiovascular responses measured. However, application of negative pressure increased blood flow to the exercising leg during EX40 and EX60. This increase in blood flow had no significant effect on systemic cardiovascular responses during EX40, but it markedly attenuated the pressor responses otherwise seen during EX60. These results demonstrate that during mild exercise, normal blood flow to exercising muscle is not a factor eliciting cardiovascular responses, whereas it elicits an important pressor effect during moderate exercise. This suggests blood flow to exercising muscle is a major determinant of cardiovascular responses during dynamic exercise at higher than moderate intensity. Copyright © 2015 the American Physiological Society.

  10. 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

  11. 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.

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

    International Nuclear Information System (INIS)

    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

  13. 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

  14. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Ebbers, T

    2001-05-01

    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

  16. 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

  17. Balancing tissue perfusion demands: cardiovascular dynamics of Cancer magister during exposure to low salinity and hypoxia.

    Science.gov (United States)

    McGaw, Iain J; McMahon, Brian R

    2003-01-01

    Decapod crustaceans inhabit aquatic environments that are frequently subjected to changes in salinity and oxygen content. The physiological responses of decapod crustaceans to either salinity or hypoxia are well documented; however, there are many fewer reports on the physiological responses during exposure to these parameters in combination. We investigated the effects of simultaneous and sequential combinations of low salinity and hypoxia on the cardiovascular physiology of the Dungeness crab, Cancer magister. Heart rate, as well as haemolymph flow rates through the anterolateral, hepatic, sternal and posterior arteries were measured using a pulsed-Doppler flowmeter. Summation of flows allowed calculation of cardiac output and division of this by heart rate yielded stroke volume. When hypoxia and low salinity were encountered simultaneously, the observed changes in cardiac properties tended to be a mix of both factors. Hypoxia caused a bradycardia, whereas exposure to low salinity was associated with a tachycardia. However, the hypoxic conditions had the dominant effect on heart rate. Although hypoxia caused an increase in stroke volume of the heart, the low salinity had a more pronounced effect, causing an overall decrease in stroke volume. The patterns of haemolymph flow through the arterial system also varied when hypoxia and low salinity were offered together. The resulting responses were a mix of those resulting from exposure to either parameter alone. When low salinity and hypoxia were offered sequentially, the parameter experienced first tended to have the dominant effect on cardiac function and haemolymph flows. Low salinity exposure was associated with an increase in heart rate, a decrease in stroke volume and cardiac output, and a concomitant decrease in haemolymph flow rates. Subsequent exposure to hypoxic conditions caused a slight decrease in rate, but other cardiovascular variables were largely unaffected. In contrast, when low salinity followed

  18. Relationship between insulin resistance and tissue blood flow in preeclampsia.

    Science.gov (United States)

    Anim-Nyame, Nick; Gamble, John; Sooranna, Suren R; Johnson, Mark R; Steer, Philip J

    2015-05-01

    Preeclampsia is characterized by generalized endothelial dysfunction and impaired maternal tissue perfusion, and insulin resistance is a prominent feature of this disease. The aim of this study was to test the hypothesis that insulin resistance in preeclampsia is related to the reduced resting tissue blood flow. We used venous occlusion plethysmography to compare the resting calf muscle blood flow (measured as QaU) in 20 nulliparous women with preeclampsia and 20 normal pregnant controls matched for maternal age, gestational age, parity and BMI during the third trimester. Fasting blood samples were obtained to measure the plasma concentrations of insulin and glucose, and to calculate the fasting insulin resistance index (FIRI), a measure of insulin resistance in both groups of women. Calf blood flow was significantly reduced in the preeclampsia group (1.93 ± 0.86 QaU), compared with normal pregnant controls (3.94 ± 1.1 QaU, P insulin concentrations and Insulin Resistance Index were significantly higher in preeclampsia compared with normal pregnancy (P insulin concentrations (r = -0.57, P = 0.008) and FIRI (r = -0.59, P = 0.006) in preeclampsia, but not in normal pregnancy. These findings support our hypothesis and raise the possibility that reduced tissue blood flow may a play a role in the increased insulin resistance seen in preeclampsia.

  19. Adipose tissue mitochondrial dysfunction triggers a lipodystrophic syndrome with insulin resistance, hepatosteatosis, and cardiovascular complications.

    Science.gov (United States)

    Vernochet, Cecile; Damilano, Federico; Mourier, Arnaud; Bezy, Olivier; Mori, Marcelo A; Smyth, Graham; Rosenzweig, Anthony; Larsson, Nils-Göran; Kahn, C Ronald

    2014-10-01

    Mitochondrial dysfunction in adipose tissue occurs in obesity, type 2 diabetes, and some forms of lipodystrophy, but whether this dysfunction contributes to or is the result of these disorders is unknown. To investigate the physiological consequences of severe mitochondrial impairment in adipose tissue, we generated mice deficient in mitochondrial transcription factor A (TFAM) in adipocytes by using mice carrying adiponectin-Cre and TFAM floxed alleles. These adiponectin TFAM-knockout (adipo-TFAM-KO) mice had a 75-81% reduction in TFAM in the subcutaneous and intra-abdominal white adipose tissue (WAT) and interscapular brown adipose tissue (BAT), causing decreased expression and enzymatic activity of proteins in complexes I, III, and IV of the electron transport chain (ETC). This mitochondrial dysfunction led to adipocyte death and inflammation in WAT and a whitening of BAT. As a result, adipo-TFAM-KO mice were resistant to weight gain, but exhibited insulin resistance on both normal chow and high-fat diets. These lipodystrophic mice also developed hypertension, cardiac hypertrophy, and cardiac dysfunction. Thus, isolated mitochondrial dysfunction in adipose tissue can lead a syndrome of lipodystrophy with metabolic syndrome and cardiovascular complications. © FASEB.

  20. 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.

  1. 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.

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

    DEFF Research Database (Denmark)

    Henriksen, O

    1991-01-01

    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...... 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...... 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...

  3. Tissue perfusion during normovolemic hemodilution investigated by a hydraulic model of the cardiovascular system.

    Science.gov (United States)

    Mirhashemi, S; Messmer, K; Intaglietta, M

    1987-01-01

    Normovolemic hemodilution on a whole body basis is studied by means of a steady flow, hydraulic analogue simulation of the cardiovascular system, based on the Casson's model and current hemodynamic and rheological data. The vasculature is divided into serially connected compartments whose hydraulic resistance is characterized by the average diameter, length, number of vessels, and the corresponding rheological properties of blood formulated by Dintenfass (1971) and Lipowsky et al. (1980). This model computes the pressure distributions in all compartments, where the calculated venous pressure modulates the cardiac function according to the Starling mechanism for cardiac performance. The alterations of flow induced by the action of the heart are added to the effects due to changes in peripheral vascular resistance as a result of hematocrit variation. This model shows that when the response of heart to the changes of venous pressure is impaired, the maximum oxygen carrying capacity occurs at 40% hematocrit (H) where it is 1% higher than normal hematocrit (H = 44%). The normal cardiac response to the changes of venous pressure, causes the maximum oxygen carrying capacity to occur at 32% H where it is 12% greater than that at normal hematocrit. Mean arteriolar pressure and capillary pressure increase while venular pressure is slightly reduced during normovolemic hemodilution.

  4. Partitioned fluid-solid coupling for cardiovascular blood flow: left-ventricular fluid mechanics.

    Science.gov (United States)

    Krittian, Sebastian; Janoske, Uwe; Oertel, Herbert; Böhlke, Thomas

    2010-04-01

    We present a 3D code-coupling approach which has been specialized towards cardiovascular blood flow. For the first time, the prescribed geometry movement of the cardiovascular flow model KaHMo (Karlsruhe Heart Model) has been replaced by a myocardial composite model. Deformation is driven by fluid forces and myocardial response, i.e., both its contractile and constitutive behavior. Whereas the arbitrary Lagrangian-Eulerian formulation (ALE) of the Navier-Stokes equations is discretized by finite volumes (FVM), the solid mechanical finite elasticity equations are discretized by a finite element (FEM) approach. Taking advantage of specialized numerical solution strategies for non-matching fluid and solid domain meshes, an iterative data-exchange guarantees the interface equilibrium of the underlying governing equations. The focus of this work is on left-ventricular fluid-structure interaction based on patient-specific magnetic resonance imaging datasets. Multi-physical phenomena are described by temporal visualization and characteristic FSI numbers. The results gained show flow patterns that are in good agreement with previous observations. A deeper understanding of cavity deformation, blood flow, and their vital interaction can help to improve surgical treatment and clinical therapy planning.

  5. Secondary flow structures under stent-induced perturbations for cardiovascular flow in a curved artery model

    International Nuclear Information System (INIS)

    Glenn, Autumn L.; Bulusu, Kartik V.; Shu Fangjun; Plesniak, Michael W.

    2012-01-01

    Secondary flows within curved arteries with unsteady forcing result from amplified centrifugal instabilities and are expected to be driven by the rapid accelerations and decelerations inherent in physiological waveforms. These secondary flows may also affect the function of curved arteries through pro-atherogenic wall shear stresses, platelet residence time and other vascular response mechanisms. Planar PIV measurements were performed under multi-harmonic non-zero-mean and physiological carotid artery waveforms at various locations in a rigid bent-pipe curved artery model. Results revealed symmetric counter-rotating vortex pairs that developed during the acceleration phases of both multi-harmonic and physiological waveforms. An idealized stent model was placed upstream of the bend, which initiated flow perturbations under physiological inflow conditions. Changes in the secondary flow structures were observed during the systolic deceleration phase (t/T ≈ 0.20–0.50). Proper Orthogonal Decomposition (POD) analysis of the flow morphologies under unsteady conditions indicated similarities in the coherent secondary-flow structures and correlation with phase-averaged velocity fields. A regime map was created that characterizes the kaleidoscope of vortical secondary flows with multiple vortex pairs and interesting secondary flow morphologies. This regime map in the curved artery model was created by plotting the secondary Reynolds number against another dimensionless acceleration-based parameter marking numbered regions of vortex pairs.

  6. Secondary flow structures under stent-induced perturbations for cardiovascular flow in a curved artery model

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, Autumn L.; Bulusu, Kartik V. [Department of Mechanical and Aerospace Engineering, George Washington University, 801 22nd Street, NW., Washington, DC 20052 (United States); Shu Fangjun [Department of Mechanical and Aerospace Engineering, New Mexico State University, MSC 3450, P.O. Box 30001, Las Cruces, NM 88003-8001 (United States); Plesniak, Michael W., E-mail: plesniak@gwu.edu [Department of Mechanical and Aerospace Engineering, George Washington University, 801 22nd Street, NW., Washington, DC 20052 (United States)

    2012-06-15

    Secondary flows within curved arteries with unsteady forcing result from amplified centrifugal instabilities and are expected to be driven by the rapid accelerations and decelerations inherent in physiological waveforms. These secondary flows may also affect the function of curved arteries through pro-atherogenic wall shear stresses, platelet residence time and other vascular response mechanisms. Planar PIV measurements were performed under multi-harmonic non-zero-mean and physiological carotid artery waveforms at various locations in a rigid bent-pipe curved artery model. Results revealed symmetric counter-rotating vortex pairs that developed during the acceleration phases of both multi-harmonic and physiological waveforms. An idealized stent model was placed upstream of the bend, which initiated flow perturbations under physiological inflow conditions. Changes in the secondary flow structures were observed during the systolic deceleration phase (t/T Almost-Equal-To 0.20-0.50). Proper Orthogonal Decomposition (POD) analysis of the flow morphologies under unsteady conditions indicated similarities in the coherent secondary-flow structures and correlation with phase-averaged velocity fields. A regime map was created that characterizes the kaleidoscope of vortical secondary flows with multiple vortex pairs and interesting secondary flow morphologies. This regime map in the curved artery model was created by plotting the secondary Reynolds number against another dimensionless acceleration-based parameter marking numbered regions of vortex pairs.

  7. 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 hyperthyroid rats and was decreased in kidney and aorta of hypothyroid rats (P hyperthyroid rats and remained unchanged in all organs of hypothyroid rats. The substrate for these enzymes, l-arginine, was reduced (P hyperthyroid rats. Levels of ODC and spermidine, its product, were increased and decreased (P 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.

  8. 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.

  9. 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.

  10. 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 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...

  11. 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.

  12. 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)

  13. 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.

  14. Platelet lysate as an autologous alternative for fetal bovine serum in cardiovascular tissue engineering

    NARCIS (Netherlands)

    Riem Vis, P.W.; Bouten, C.V.C.; Sluijter, J.P.G.; Herwerden, van L.A.; Kluin, J.

    2010-01-01

    There is an ongoing search for alternative tissue culture sera to engineer autologous tissues, since use of fetal bovine serum (FBS) is limited under Good Tissue Practice (GTP) guidelines. We compared FBS with human Platelet-lysate (PL) in media for in vitro cell culture. A threefold increase in

  15. 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.

  16. 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

  17. 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...

  18. 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.

  19. 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)

  20. Sequential use of human-derived medium supplements favours cardiovascular tissue engineering

    NARCIS (Netherlands)

    Riem Vis, P.W.; Sluijter, J.P.G.; Soekhradj - Soechit, R.S.; Herwerden, van L.A.; Kluin, J.; Bouten, C.V.C.

    2012-01-01

    For clinical application of tissue engineering strategies, the use of animal-derived serum in culture medium is not recommended, because it can evoke immune responses in patients. We previously observed that human platelet-lysate (PL) is favourable for cell expansion, but generates weaker tissue as

  1. A Dual Flow Bioreactor for Cartilage Tissue Engineering

    NARCIS (Netherlands)

    Spitters, Tim

    2014-01-01

    Preventing the onset of a degenerative disease like osteoarthritis by restoring tissue function before cartilage degradation occurs will decrease health costs, reduce socio-economic burdens of patients and preserve quality of life. However, producing ex vivo cartilage implants of clinically relevant

  2. Radionuclide investigation of the blood flow in tumor and normal rat tissues in induced hyperglycemia

    International Nuclear Information System (INIS)

    Istomin, Yu.P.; Shitikov, B.D.; Markova, L.V.

    1991-01-01

    Radionuclide angiography was performed in rats with transplantable tumors. Induced hyperglycemia was shown to result in blood flow inhibition in tumor and normal tissues of tumor-bearing rats. Some differences were revealed in a degree of reversibility of blood flow disorders in tissues of the above strains. The results obtained confirmed the advisability of radiation therapy at the height of a decrease in tumor blood

  3. 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

  4. Patient-specific cardiovascular progenitor cells derived from integration-free induced pluripotent stem cells for vascular tissue regeneration.

    Science.gov (United States)

    Hu, Jiang; Wang, Yongyu; Jiao, Jiao; Liu, Zhongning; Zhao, Chao; Zhou, Zhou; Zhang, Zhanpeng; Forde, Kaitlynn; Wang, Lunchang; Wang, Jiangang; Baylink, David J; Zhang, Xiao-Bing; Gao, Shaorong; Yang, Bo; Chen, Y Eugene; Ma, Peter X

    2015-12-01

    Tissue-engineered blood vessels (TEBVs) are promising in regenerating a live vascular replacement. However, the vascular cell source is limited, and it is crucial to develop a scaffold that accommodates new type of vascular progenitor cells and facilitates in vivo lineage specification of the cells into functional vascular smooth muscle cells (VSMCs) to regenerate vascular tissue. In the present study, integration-free human induced pluripotent stem cells (hiPSCs) were established from patient peripheral blood mononuclear cells through episomal vector nucleofection of reprogramming factors. The established hiPSCs were then induced into mesoderm-originated cardiovascular progenitor cells (CVPCs) with a highly efficient directed lineage specification method. The derived CVPCs were demonstrated to be able to differentiate into functional VSMCs. Subcutaneous implantation of CVPCs seeded on macroporous nanofibrous poly(l-lactide) scaffolds led to in vivo VSMC lineage specification and matrix deposition inside the scaffolds. In summary, we established integration-free patient-specific hiPSCs from peripheral blood mononuclear cells, derived CVPCs through directed lineage specification, and developed an advanced scaffold for these progenitor cells to further differentiate in vivo into VSMCs and regenerate vascular tissue in a subcutaneous implantation model. This study has established an efficient patient-specific approach towards in vivo regeneration of vascular tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Effect of spinal sympathetic blockade upon postural changes of blood flow in human peripheral tissues

    DEFF Research Database (Denmark)

    Skagen, K; Haxholdt, O; Henriksen, O

    1982-01-01

    local nervous blockade was induced by Lidocaine in 133Xe labelled subcutaneous tissue on one side. During epidural blockade and tilt blood flow increased by 12% whereas blood flow decreased by 30% on the control side. Thus epidural blockade had no influence on the vasoconstrictor response...

  6. Adipose tissue mitochondrial dysfunction triggers a lipodystrophic syndrome with insulin resistance, hepatosteatosis, and cardiovascular complications

    OpenAIRE

    Vernochet, Cecile; Damilano, Federico; Mourier, Arnaud; Bezy, Olivier; Mori, Marcelo A.; Smyth, Graham; Rosenzweig, Anthony; Larsson, Nils-Göran; Kahn, C. Ronald

    2014-01-01

    Mitochondrial dysfunction in adipose tissue occurs in obesity, type 2 diabetes, and some forms of lipodystrophy, but whether this dysfunction contributes to or is the result of these disorders is unknown. To investigate the physiological consequences of severe mitochondrial impairment in adipose tissue, we generated mice deficient in mitochondrial transcription factor A (TFAM) in adipocytes by using mice carrying adiponectin-Cre and TFAM floxed alleles. These adiponectin TFAM-knockout (adipo-...

  7. 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

    2013-01-01

    The purpose of this investigation is to use a computational model to compare a synchronized valveless pulsatile left ventricular assist device with 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 the 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 with 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 with 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.

  8. The association between measurement sites of visceral adipose tissue and cardiovascular risk factors after caloric restriction in obese Korean women.

    Science.gov (United States)

    Lee, Hye-Ok; Yim, Jung-Eun; Lee, Jeong-Sook; Kim, Young-Seol; Choue, Ryowon

    2013-02-01

    Quantities as well as distributions of adipose tissue (AT) are significantly related to cardiovascular disease (CVD) risk factors and can be altered with caloric restriction. This study investigated which cross-sectional slice location of AT is most strongly correlated with changes in CVD risk factors after caloric restriction in obese Korean women. Thirty-three obese pre-menopausal Korean women (32.4 ± 8.5 yrs, BMI 27.1 ± 2.3 kg/m(2)) participated in a 12 weeks caloric restriction program. Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were measured using computed tomography (CT) scans at the sites of L2-L3, L3-L4, and L4-L5. Fasting serum levels of glucose, insulin, triglyceride, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), leptin and homeostasis model assessment-insulin resistance (HOMA-IR) were observed. Pearson's partial correlation coefficients were used to assess the relationship between AT measurement sites and changes in CVD risk factors after calorie restriction. When calories were reduced by 350 kcal/day for 12 weeks, body weight (-2.7%), body fat mass (-8.2%), and waist circumference (-5.8%) all decreased (P restriction, serum levels of glucose (-4.6%), TC (-6.2%), LDL-C (-5.3%), leptin (-17.6%) and HOMA-IR (-18.2%) decreased significantly (P restriction.

  9. 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)

  10. 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

  11. Studies of nontarget-mediated distribution of human full-length IgG1 antibody and its FAb fragment in cardiovascular and metabolic-related tissues.

    Science.gov (United States)

    Davidsson, Pia; Söderling, Ann-Sofi; Svensson, Lena; Ahnmark, Andrea; Flodin, Christine; Wanag, Ewa; Screpanti-Sundqvist, Valentina; Gennemark, Peter

    2015-05-01

    Tissue distribution and pharmacokinetics (PK) of full-length nontargeted antibody and its antigen-binding fragment (FAb) were evaluated for a range of tissues primarily of interest for cardiovascular and metabolic diseases. Mice were intravenously injected with a dose of 10 mg/kg of either human IgG1or its FAb fragment; perfused tissues were collected at a range of time points over 3 weeks for the human IgG1 antibody and 1 week for the human FAb antibody. Tissues were homogenized and antibody concentrations were measured by specific immunoassays on the Gyros system. Exposure in terms of maximum concentration (Cmax ) and area under the curve was assessed for all nine tissues. Tissue exposure of full-length antibody relative to plasma exposure was found to be between 1% and 10%, except for brain (0.2%). Relative concentrations of FAb antibody were the same, except for kidney tissue, where the antibody concentration was found to be ten times higher than in plasma. However, the absolute tissue uptake of full-length IgG was significantly higher than the absolute tissue uptake of the FAb antibody. This study provides a reference PK state for full-length whole and FAb antibodies in tissues related to cardiovascular and metabolic diseases that do not include antigen or antibody binding. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. 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.

  13. 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

  14. Real-time quantification of subcellular H2O2 and glutathione redox potential in living cardiovascular tissues.

    Science.gov (United States)

    Panieri, Emiliano; Millia, Carlo; Santoro, Massimo M

    2017-08-01

    Detecting and measuring the dynamic redox events that occur in vivo is a prerequisite for understanding the impact of oxidants and redox events in normal and pathological conditions. These aspects are particularly relevant in cardiovascular tissues wherein alterations of the redox balance are associated with stroke, aging, and pharmacological intervention. An ambiguous aspect of redox biology is how redox events occur in subcellular organelles including mitochondria, and nuclei. Genetically-encoded Rogfp2 fluorescent probes have become powerful tools for real-time detection of redox events. These probes detect hydrogen peroxide (H 2 O 2 ) levels and glutathione redox potential (E GSH ), both with high spatiotemporal resolution. By generating novel transgenic (Tg) zebrafish lines that express compartment-specific Rogfp2-Orp1 and Grx1-Rogfp2 sensors we analyzed cytosolic, mitochondrial, and the nuclear redox state of endothelial cells and cardiomyocytes of living zebrafish embryos. We provide evidence for the usefulness of these Tg lines for pharmacological compounds screening by addressing the blocking of pentose phosphate pathways (PPP) and glutathione synthesis, thus altering subcellular redox state in vivo. Rogfp2-based transgenic zebrafish lines represent valuable tools to characterize the impact of redox changes in living tissues and offer new opportunities for studying metabolic driven antioxidant response in biomedical research. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. 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.

  16. Tissues viability and blood flow sensing based on a new nanophotonics method

    Science.gov (United States)

    Yariv, Inbar; Haddad, Menashe; Duadi, Hamootal; Motiei, Menachem; Fixler, Dror

    2018-02-01

    Extracting optical parameters of turbid medium (e.g. tissue) by light reflectance signals is of great interest and has many applications in the medical world, life science, material analysis and biomedical optics. The reemitted light from an irradiated tissue is affected by the light's interaction with the tissue components and contains the information about the tissue structure and physiological state. In this research we present a novel noninvasive nanophotonics technique, i.e., iterative multi-plane optical property extraction (IMOPE) based on reflectance measurements. The reflectance based IMOPE was applied for tissue viability examination, detection of gold nanorods (GNRs) within the blood circulation as well as blood flow detection using the GNRs presence within the blood vessels. The basics of the IMOPE combine a simple experimental setup for recording light intensity images with an iterative Gerchberg-Saxton (G-S) algorithm for reconstructing the reflected light phase and computing its standard deviation (STD). Changes in tissue composition affect its optical properties which results in changes in the light phase that can be measured by its STD. This work presents reflectance based IMOPE tissue viability examination, producing a decrease in the computed STD for older tissues, as well as investigating their organic material absorption capability. Finally, differentiation of the femoral vein from adjacent tissues using GNRs and the detection of their presence within blood circulation and tissues are also presented with high sensitivity (better than computed tomography) to low quantities of GNRs (<3 mg).

  17. Noncontact 3-D Speckle Contrast Diffuse Correlation Tomography of Tissue Blood Flow Distribution.

    Science.gov (United States)

    Huang, Chong; Irwin, Daniel; Zhao, Mingjun; Shang, Yu; Agochukwu, Nneamaka; Wong, Lesley; Yu, Guoqiang

    2017-10-01

    Recent advancements in near-infrared diffuse correlation techniques and instrumentation have opened the path for versatile deep tissue microvasculature blood flow imaging systems. Despite this progress there remains a need for a completely noncontact, noninvasive device with high translatability from small/testing (animal) to large/target (human) subjects with trivial application on both. Accordingly, we discuss our newly developed setup which meets this demand, termed noncontact speckle contrast diffuse correlation tomography (nc_scDCT). The nc_scDCT provides fast, continuous, portable, noninvasive, and inexpensive acquisition of 3-D tomographic deep (up to 10 mm) tissue blood flow distributions with straightforward design and customization. The features presented include a finite-element-method implementation for incorporating complex tissue boundaries, fully noncontact hardware for avoiding tissue compression and interactions, rapid data collection with a diffuse speckle contrast method, reflectance-based design promoting experimental translation, extensibility to related techniques, and robust adjustable source and detector patterns and density for high resolution measurement with flexible regions of interest enabling unique application-specific setups. Validation is shown in the detection and characterization of both high and low contrasts in flow relative to the background using tissue phantoms with a pump-connected tube (high) and phantom spheres (low). Furthermore, in vivo validation of extracting spatiotemporal 3-D blood flow distributions and hyperemic response during forearm cuff occlusion is demonstrated. Finally, the success of instrument feasibility in clinical use is examined through the intraoperative imaging of mastectomy skin flap.

  18. Roadmap for cardiovascular circulation model

    Science.gov (United States)

    Bradley, Christopher P.; Suresh, Vinod; Mithraratne, Kumar; Muller, Alexandre; Ho, Harvey; Ladd, David; Hellevik, Leif R.; Omholt, Stig W.; Chase, J. Geoffrey; Müller, Lucas O.; Watanabe, Sansuke M.; Blanco, Pablo J.; de Bono, Bernard; Hunter, Peter J.

    2016-01-01

    Abstract Computational models of many aspects of the mammalian cardiovascular circulation have been developed. Indeed, along with orthopaedics, this area of physiology is one that has attracted much interest from engineers, presumably because the equations governing blood flow in the vascular system are well understood and can be solved with well‐established numerical techniques. Unfortunately, there have been only a few attempts to create a comprehensive public domain resource for cardiovascular researchers. In this paper we propose a roadmap for developing an open source cardiovascular circulation model. The model should be registered to the musculo‐skeletal system. The computational infrastructure for the cardiovascular model should provide for near real‐time computation of blood flow and pressure in all parts of the body. The model should deal with vascular beds in all tissues, and the computational infrastructure for the model should provide links into CellML models of cell function and tissue function. In this work we review the literature associated with 1D blood flow modelling in the cardiovascular system, discuss model encoding standards, software and a model repository. We then describe the coordinate systems used to define the vascular geometry, derive the equations and discuss the implementation of these coupled equations in the open source computational software OpenCMISS. Finally, some preliminary results are presented and plans outlined for the next steps in the development of the model, the computational software and the graphical user interface for accessing the model. PMID:27506597

  19. Modeling and design of optimal flow perfusion bioreactors for tissue engineering applications.

    Science.gov (United States)

    Hidalgo-Bastida, L Araida; Thirunavukkarasu, Sundaramoorthy; Griffiths, Sarah; Cartmell, Sarah H; Naire, Shailesh

    2012-04-01

    Perfusion bioreactors have been used in different tissue engineering applications because of their consistent distribution of nutrients and flow-induced shear stress within the tissue-engineering scaffold. A widely used configuration uses a scaffold with a circular cross-section enclosed within a cylindrical chamber and inlet and outlet pipes which are connected to the chamber on either side through which media is continuously circulated. However, fluid-flow experiments and simulations have shown that the majority of the flow perfuses through the center. This pattern creates stagnant zones in the peripheral regions as well as in those of high flow rate near the inlet and outlet. This non-uniformity of flow and shear stress, owing to a circular design, results in limited cell proliferation and differentiation in these areas. The focus of this communication is to design an optimized perfusion system using computational fluid dynamics as a mathematical tool to overcome the time-consuming trial and error experimental method. We compared the flow within a circular and a rectangular bioreactor system. Flow simulations within the rectangular bioreactor are shown to overcome the limitations in the circular design. This communication challenges the circular cross-section bioreactor configuration paradigm and provides proof of the advantages of the new design over the existing one. Copyright © 2011 Wiley Periodicals, Inc.

  20. Free flow and capillary isoelectric focusing of bacteria from the tomatoes plant tissues

    Czech Academy of Sciences Publication Activity Database

    Horká, Marie; Horký, J.; Matoušková, H.; Šlais, Karel

    2009-01-01

    Roč. 1216, č. 6 (2009), s. 1019-1024 ISSN 0021-9673 R&D Projects: GA AV ČR IAAX00310701 Institutional research plan: CEZ:AV0Z40310501 Keywords : free flow and capillary IEF * isoelectric point of microbes * tomatoes plant tissue suspension Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 4.101, year: 2009

  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. 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

  3. Data on metabolic-dependent antioxidant response in the cardiovascular tissues of living zebrafish under stress conditions

    Directory of Open Access Journals (Sweden)

    Emiliano Panieri

    2017-06-01

    Full Text Available In this article we used transgenic zebrafish lines that express compartment-specific isoforms of the roGFP2-Orp1 and Grx1-roGFP2 biosensors, described in Panieri et al (2017 [1], to test the contribute of the pentose phosphate pathway and of the glutathione biosynthesis in the antioxidant capacity of myocardial and endothelial cells in vivo. The transgenic zebrafish embryos were subdued to metabolic inhibition and subsequently challenged with H2O2 or the redox-cycling agent menadione to respectively mimic acute or chronic oxidative stress. Confocal time-lapse recordings were performed to follow the compartmentalized H2O2 and EGSH changes in the cardiovascular tissues of zebrafish embryos at 48 h post fertilization. After sequential excitation at 405 nm and 488 nm the emission was collected between 500–520 nm every 2 min for an overall duration of 60 min. The 405/488 nm ratio was normalized to the initial value obtained before oxidants addition and plotted over time. The analysis and the interpretation of the data can be found in the associated article [1].

  4. Pan-FGFR inhibition leads to blockade of FGF23 signaling, soft tissue mineralization, and cardiovascular dysfunction.

    Science.gov (United States)

    Yanochko, Gina M; Vitsky, Allison; Heyen, Jonathan R; Hirakawa, Brad; Lam, Justine L; May, Jeff; Nichols, Tim; Sace, Frederick; Trajkovic, Dusko; Blasi, Eileen

    2013-10-01

    The fibroblast growth factor receptors (FGFR) play a major role in angiogenesis and are desirable targets for the development of therapeutics. Groups of Wistar Han rats were dosed orally once daily for 4 days with a small molecule pan-FGFR inhibitor (5mg/kg) or once daily for 6 days with a small molecule MEK inhibitor (3mg/kg). Serum phosphorous and FGF23 levels increased in all rats during the course of the study. Histologically, rats dosed with either drug exhibited multifocal, multiorgan soft tissue mineralization. Expression levels of the sodium phosphate transporter Npt2a and the vitamin D-metabolizing enzymes Cyp24a1 and Cyp27b1 were modulated in kidneys of animals dosed with the pan-FGFR inhibitor. Both inhibitors decreased ERK phosphorylation in the kidneys and inhibited FGF23-induced ERK phosphorylation in vitro in a dose-dependent manner. A separate cardiovascular outcome study was performed to monitor hemodynamics and cardiac structure and function of telemetered rats dosed with either the pan-FGFR inhibitor or MEK inhibitor for 3 days. Both compounds increased blood pressure (~+ 17 mmHg), decreased heart rate (~-75 bpm), and modulated echocardiography parameters. Our data suggest that inhibition of FGFR signaling following administration of either pan-FGFR inhibitor or MEK inhibitor interferes with the FGF23 pathway, predisposing animals to hyperphosphatemia and a tumoral calcinosis-like syndrome in rodents.

  5. 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

  6. Effect of flow on vascular endothelial cells grown in tissue culture on polytetrafluoroethylene grafts

    International Nuclear Information System (INIS)

    Sentissi, J.M.; Ramberg, K.; O'Donnell, T.F. Jr.; Connolly, R.J.; Callow, A.D.

    1986-01-01

    Vascular grafts lined with endothelial cells (EC) grown to confluence in culture before implantation may provide a thromboresistant flow surface. Growth of EC on and their adherence to currently available prosthetic materials under conditions of flow are two impediments remaining in the development of such a graft. To address these problems, 22 polytetrafluoroethylene grafts (PTFE) (5 cm by 4 mm inside diameter) were pretreated with collagen and fibronectin, seeded with 2 to 3 X 10(6) bovine aortic EC per graft, and placed in tissue culture (seeded grafts). Twenty-two grafts pretreated with collagen and fibronectin alone served as controls. After 2 weeks morphologic studies revealed that 20/22 seeded grafts were lined with a confluent endothelial layer. Indium 111-oxine was then used to label the EC-seeded grafts. After exposure to either low (25 ml/min) or high (200 ml/min) flow rates for 60 minutes in an in vitro circuit, examination of the luminal surface of the graft by light microscopy and scanning electron microscopy revealed minimal loss of EC. These findings were corroborated by radionuclide scans that showed an insignificant loss of the EC-associated indium label during exposure to flow (7% low flow, 11% high flow). Pretreatment of PTFE grafts with collagen and fibronectin thus promotes both attachment and adherence of EC even under flow conditions

  7. 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.

  8. Measurement of subcutaneous adipose tissue blood flow in the morbidly obese using a laser Doppler velocimeter

    Science.gov (United States)

    Klassen, Gerald A.; Paton, Barry E.; Maksym, Geoff; Janigan, David; Perey, Bernard

    1992-08-01

    Using a laser Doppler velocimeter (LDV) subcutaneous adipose tissue blood flow (AF) was recorded in the upright and supine positions in the upper and lower abdomen in 22 morbidly obese patients before gastroplasty. Age was 42 +/- 3 (mean +/- SEM), weight 135 +/- 7 kg, and body mass index (BMI) 51 +/- 3. Adipose flow expressed as mV was: supine, upper abdomen 647 +/- 23, lower abdomen 604 +/- 24; upright, upper abdomen 621 +/- 27, lower abdomen 607 +/- 29. AF was significantly more in the upper than lower abdomen (supine position) and AF was significantly lower in the lower abdomen upright than the upper abdomen supine. Regression analysis of age indicates that blood flow decreases in the lower abdomen so that in the supine position the difference between upper and lower abdomen AF increases. Similar analysis of BMI did not indicate significant trends. These data indicate that with morbid obesity there is lower tissue blood flow to the lower abdomen. This may explain why such patients may develop areas of painful ischemic necrosis in the dependent region of their anterior abdominal pannus.

  9. 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.

  10. 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

    AD) greater than the median value presented the worst clinical outcome compared to those with isolated sFV less than the median value or sAD greater than the median value, suggesting an additive effect of these two variables. Further, Kaplan-Meier analysis demonstrated worse outcome for individuals with s...... intima-media thickness and clinically defined high cardiovascular risk did not. Furthermore, area under the receiver-operating characteristic curve for sFV/sAD was higher than that for Framingham risk score (0.77 versus 0.64; P = 0.045), whereas adding sFV/sAD to the Framingham risk factors resulted...

  11. 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

  12. 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.

  13. 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.

  14. Effect of computed tomography noise and tissue heterogeneity on cerebral blood flow determination by xenon-enhanced computed tomography

    International Nuclear Information System (INIS)

    Good, W.F.; Gur, D.

    1987-01-01

    The errors associated with derivation of cerebral blood flow values by the xenon-enhanced computed tomography (CT) method have been evaluated as a function of tissue heterogeneity and CT noise. The results of this study indicate that CT noise introduces large errors in the derived flow value when data for a single, unprocessed voxel are used for this purpose. CT noise increases the derived flow values in a systematic way. Tissue heterogeneity results in a systematic error which lowers the derived flow values. Errors due to both parameters are computed for typical and extreme conditions

  15. 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

    International Nuclear Information System (INIS)

    Maroules, Christopher D.; Peshock, Ronald M.; Chang, Alice Y.; Kontak, Andrew; Dimitrov, Ivan; Kotys, Melanie

    2010-01-01

    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

  16. 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

    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 da...... 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....

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

    KAUST Repository

    Malara, N.M.; Trunzo, V.; Musolino, G.; Aprigliano, S.; Rotta, G.; Macrina, L.; Limongi, T.; Gratteri, S.; Di Fabrizio, Enzo M.; Renzulli, A.; Fini, M.; Mollace, V.

    2015-01-01

    -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

  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...

  19. 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 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...

  20. Changes in regional blood flow of normal and tumor tissues following hyperthermia and combined X-ray irradiation

    International Nuclear Information System (INIS)

    Suga, Kazuyoshi

    1986-01-01

    Hyperthermia and X-ray irradiation were given to Ehrlich tumors, which were induced in the ventrum of the right hind foot of ICR mice, and to the normal tissues. Their effects on regional blood flow were examined using Xe-133 local clearance method. Blood flow of the normal tissues remained unchanged by heating at 41 deg C for 30 minutes, and increased by heating at 43 deg C and 45 deg C for 30 minutes. On the contrary, blood flow of the tumors decreased with an increase in temperature. When hypertermia (43 deg C for 30 minutes) was combined with irradiation of 30 Gy, decrease in blood flow of the tumors was greater than the normal tissues at 24 hours. Blood flow of the tumors depended on tumor size. The decreased amount of blood flow by hyperthermia was more for tumors > 250 mm 3 than tumors 3 . Blood flow ratios of tumor to normal tissues were also smaller in tumors > 250 mm 3 than tumors 3 . In the case of tumors 3 , blood flow tended to return to normal at 3 hr after heating at 43 deg C for 30 min. However, this was not seen in tumors > 250 mm 3 . (Namekawa, K.)

  1. The regulation of subcutaneous adipose tissue blood flow in the ischaemic forefoot during 24 hours

    International Nuclear Information System (INIS)

    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 μCi 133-Xenon in 0.1 ml isotonic saline injected into the subcutaneous adipose tissue in the forefoot. The detector is connected to a memory unit allowing for storage of data. Due to the short distance, the recorded elimination rate constant must be corrected for combined convection and diffusion of the radioactive indicator. After reconstructive vascular surgery, the 24-hour blood flow pattern normalized although the ankle/arm systolic blood pressure index did not come within normal range. SBF during day-time activities decreased by up to 50% postoperatively. This is caused by the reappearance of the local, sympathetic, veno-arteriolar vasoconstrictor response. During sleep SBF increased by 71%. The term postreconstructuve hyperamia seems improper, at least in a long-term context, normalization of preoperative ischaemia is a more correct notation. The coefficient of variation of nocturnal SBF was calculated to 10%. The method thus seems apt as a monitor in medical therapy for occlusive arterial disease. Changes of λ has, however, to be considered in each study. 94 refs. (EG)

  2. 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.

  3. Use of flow cytometry for high-throughput cell population estimates in fixed brain tissue

    Directory of Open Access Journals (Sweden)

    Nicole A Young

    2012-07-01

    Full Text Available The numbers and types of cells in an area of cortex define its function. Therefore it is essential to characterize the numbers and distributions of total cells in areas of the cortex, as well as to identify numbers of subclasses of neurons and glial cells. To date, the large size of the primate brain and the lack of innovation in cell counting methods have been a roadblock to obtaining high-resolution maps of cell and neuron density across the cortex in humans and non-human primates. Stereological counting methods and the isotropic fractionator are valuable tools for estimating cell numbers, but are better suited to smaller, well-defined brain structures or to cortex as a whole. In the present study, we have extended our flow-cytometry based counting method, the flow fractionator (Collins et al., 2010a, to include high-throughput total cell population estimates in homogenized cortical samples. We demonstrate that our method produces consistent, accurate and repeatable cell estimates quickly. The estimates we report are in excellent agreement with estimates for the same samples obtained using a Neubauer chamber and a fluorescence microscope. We show that our flow cytometry-based method for total cell estimation in homogenized brain tissue is more efficient and more precise than manual counting methods. The addition of automated nuclei counting to our flow fractionator method allows for a fully automated, rapid characterization of total cells and neuronal and non-neuronal populations in human and non-human primate brains, providing valuable data to further our understanding of the functional organization of normal, aging and diseased brains.

  4. 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

  5. Time dependency of local cerebral blood flow measurements caused by regional variations in tissue transit time

    International Nuclear Information System (INIS)

    Lear, J.L.; Kasliwal, R.; Feyerabend, A.

    1990-01-01

    Calculated values of local cerebral blood flow (LCBF) using the diffusible tracer model are assumed to be independent of time as long as experiments are brief enough to prevent tissue saturation. This paper investigates the effects of CTT variation on LCBF measurements. Using double-label quantitative digital autoradiography, we compared iodoantipyrine (IAP)-based LCBF measurements obtained with tracer infusions of different lengths of time. Lightly anesthetized rats were given simultaneous ramp infusions of C-14 IAP (45 seconds) and I-123 IAP (15 seconds) and immediately sacrificed. Two autoradiograms of each brain section, one representing I-123 and the other representing C-14, were produced, digitized, and converted into images of LCBF based on the 15- and 45-second infusion periods. The LCBF image pairs were compared on a pixel-by-pixel basis

  6. Tissue

    Directory of Open Access Journals (Sweden)

    David Morrissey

    2012-01-01

    Full Text Available Purpose. In vivo gene therapy directed at tissues of mesenchymal origin could potentially augment healing. We aimed to assess the duration and magnitude of transene expression in vivo in mice and ex vivo in human tissues. Methods. Using bioluminescence imaging, plasmid and adenoviral vector-based transgene expression in murine quadriceps in vivo was examined. Temporal control was assessed using a doxycycline-inducible system. An ex vivo model was developed and optimised using murine tissue, and applied in ex vivo human tissue. Results. In vivo plasmid-based transgene expression did not silence in murine muscle, unlike in liver. Although maximum luciferase expression was higher in muscle with adenoviral delivery compared with plasmid, expression reduced over time. The inducible promoter cassette successfully regulated gene expression with maximum levels a factor of 11 greater than baseline. Expression was re-induced to a similar level on a temporal basis. Luciferase expression was readily detected ex vivo in human muscle and tendon. Conclusions. Plasmid constructs resulted in long-term in vivo gene expression in skeletal muscle, in a controllable fashion utilising an inducible promoter in combination with oral agents. Successful plasmid gene transfection in human ex vivo mesenchymal tissue was demonstrated for the first time.

  7. 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

  8. Microvascularity, blood flow and tissue structure at the subchondral plate using an X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Muthuvelu, P.; Ellis, R.E.; Green, E.M.; Attenburrow, D.; Arkill, K.; Colridge, D.B.; Winlove, C.P.; Bradley, D.A.

    2007-01-01

    The measurement of blood flow and blood in bone and cartilaginous tissues is crucial to understanding of the development of various diseases, but it presents a formidable technical challenge. We have therefore developed a method based on the detection of metallized microspheres using X-ray fluorescence. This approach provides unrivalled sensitivity and spatial resolution and also allows us simultaneously to measure other markers of the metabolic status of the tissue. (author)

  9. 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.

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

    Science.gov (United States)

    Shang, Yu; Yu, Guoqiang

    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 N th-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 B ). The purpose of this study is to extend the capability of the N th-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 B in the brain layer with a step decrement of 10% while maintaining αD B values constant in other layers. Simulation results demonstrate the accuracy (errors 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.

  11. 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.

  12. 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.

  13. In situ tissue engineering: endothelial growth patterns as a function of flow diverter design.

    Science.gov (United States)

    Marosfoi, Miklos; Langan, Erin T; Strittmatter, Lara; van der Marel, Kajo; Vedantham, Srinivasan; Arends, Jennifer; Lylyk, Ivan R; Loganathan, Siddharth; Hendricks, Gregory M; Szikora, Istvan; Puri, Ajit S; Wakhloo, Ajay K; Gounis, Matthew J

    2017-10-01

    Vascular remodeling in response to implantation of a tissue engineering scaffold such as a flow diverter (FD) leads to the cure of intracranial aneurysms. We hypothesize that the vascular response is dependent on FD design, and CD34+ progenitor cells play an important role in the endothelialization of the implant. Sixteen rabbit aneurysms were randomly treated with two different single-layer braided FDs made of cobalt-chrome alloys. The FD-48 and FD-72 devices had 48 and 72 wires, respectively. Aneurysm occlusion rate was assessed during the final digital subtraction angiogram at 10, 20, 30, and 60 days (n=2 per device per time point). Implanted vessels were analyzed with scanning electron microscopy for tissue coverage, endothelialization, and immuno-gold labeling for CD34+ cells. Complete aneurysm occlusion rates were similar between the devices; however, complete or near complete occlusion was more frequently observed in aneurysms with neck ≤4.2 mm (p=0.008). Total tissue coverage at 10 days over the surface of the FD-48 and FD-72 devices was 56.4±11.6% and 76.6±3.6%, respectively. Endothelial cell growth over the surface was time-dependent for the FD-72 device (Spearman's r=0.86, p=0.013) but not for the FD-48 device (Spearman's r=-0.59, p=0.094). The endothelialization score was marginally correlated with the distance from the aneurysm neck for the FD-48 device (Spearman's r=1, p=0.083) but not for the FD-72 device (Spearman's r=0.8, p=0.33). CD34+ cells were present along the entirety of both devices at all time points. This study gives preliminary evidence that temporal and spatial endothelialization is dependent on FD design. Circulating CD34+ progenitor cells contribute to endothelialization throughout the healing process. 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/.

  14. 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...

  15. An investigation of the flow dependence of temperature gradients near large vessels during steady state and transient tissue heating

    International Nuclear Information System (INIS)

    Kolios, M.C.; Worthington, A.E.; Hunt, J.W.; Holdsworth, D.W.; Sherar, M.D.

    1999-01-01

    Temperature distributions measured during thermal therapy are a major prognostic factor of the efficacy and success of the procedure. Thermal models are used to predict the temperature elevation of tissues during heating. Theoretical work has shown that blood flow through large blood vessels plays an important role in determining temperature profiles of heated tissues. In this paper, an experimental investigation of the effects of large vessels on the temperature distribution of heated tissue is performed. The blood flow dependence of steady state and transient temperature profiles created by a cylindrical conductive heat source and an ultrasound transducer were examined using a fixed porcine kidney as a flow model. In the transient experiments, a 20 s pulse of hot water, 30 deg. C above ambient, heated the tissues. Temperatures were measured at selected locations in steps of 0.1 mm. It was observed that vessels could either heat or cool tissues depending on the orientation of the vascular geometry with respect to the heat source and that these effects are a function of flow rate through the vessels. Temperature gradients of 6 deg. C mm -1 close to large vessels were routinely measured. Furthermore, it was observed that the temperature gradients caused by large vessels depended on whether the heating source was highly localized (i.e. a hot needle) or more distributed (i.e. external ultrasound). The gradients measured near large vessels during localized heating were between two and three times greater than the gradients measured during ultrasound heating at the same location, for comparable flows. Moreover, these gradients were more sensitive to flow variations for the localized needle heating. X-ray computed tomography data of the kidney vasculature were in good spatial agreement with the locations of all of the temperature variations measured. The three-dimensional vessel path observed could account for the complex features of the temperature profiles. The flow

  16. Laser sintering fabrication of three-dimensional tissue engineering scaffolds with a flow channel network.

    Science.gov (United States)

    Niino, T; Hamajima, D; Montagne, K; Oizumi, S; Naruke, H; Huang, H; Sakai, Y; Kinoshita, H; Fujii, T

    2011-09-01

    The fabrication of tissue engineering scaffolds for the reconstruction of highly oxygen-dependent inner organs is discussed. An additive manufacturing technology known as selective laser sintering was employed to fabricate a highly porous scaffold with an embedded flow channel network. A porogen leaching system was used to obtain high porosity. A prototype was developed using the biodegradable plastic polycaprolactone and sodium chloride as the porogen. A high porosity of 90% was successfully obtained. Micro x-ray CT observation was carried out to confirm that channels with a diameter of approximately 1 mm were generated without clogging. The amount of residual salt was 930 µg while the overall volume of the scaffold was 13 cm(3), and it was confirmed that the toxicity of the salt was negligible. The hydrophilization of the scaffold to improve cell adhesion on the scaffold is also discussed. Oxygen plasma ashing and hydrolysis with sodium hydroxide, typically employed to improve the hydrophilicity of plastic surfaces, were tested. The improvement of hydrophilicity was confirmed by an increase in water retention by the porous scaffold from 180% to 500%.

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

    International Nuclear Information System (INIS)

    Shang, Yu; Yu, Guoqiang

    2014-01-01

    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 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 B in the brain layer with a step decrement of 10% while maintaining αD 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.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. Improvement of the in vivo cellular repopulation of decellularized cardiovascular tissues by a detergent-free, non-proteolytic, actin-disassembling regimen.

    Science.gov (United States)

    Assmann, Alexander; Struß, Marc; Schiffer, Franziska; Heidelberg, Friederike; Munakata, Hiroshi; Timchenko, Elena V; Timchenko, Pavel E; Kaufmann, Tim; Huynh, Khon; Sugimura, Yukiharu; Leidl, Quentin; Pinto, Antonio; Stoldt, Volker R; Lichtenberg, Artur; Akhyari, Payam

    2017-12-01

    Low immunogenicity and high repopulation capacity are crucial determinants for the functional and structural performance of acellular cardiovascular implants. The present study evaluates a detergent-free, non-proteolytic, actin-disassembling regimen (BIO) for decellularization of heart valve and vessel grafts, particularly focusing on their bio-functionality. Rat aortic conduits (rAoC; n = 89) and porcine aortic valve samples (n = 106) are decellularized using detergents (group DET) or the BIO regimen. BIO decellularization results in effective elimination of cellular proteins and significantly improves removal of DNA as compared with group DET, while the extracellular matrix (ECM) structure as well as mechanical properties are preserved. The architecture of rAoC in group BIO allows for improved bio-functionalization with fibronectin (FN) in a standardized rat implantation model: BIO treatment significantly increases speed and amount of autologous medial cellular repopulation in vivo (p < 0.001) and decreases the formation of hyperplastic intima (p < 0.001) as compared with FN-coated DET-decellularized grafts. Moreover, there are no signs of infiltration with inflammatory cells. The present biological, detergent-free, non-proteolytic regimen balances effective decellularization and ECM preservation in cardiovascular grafts, and provides optimized bio-functionality. Additionally, this study implies that the actin-disassembling regimen may be a promising approach for bioengineering of acellular scaffolds from other muscular tissues, as for example myocardium or intestine. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Flow-Through Free Fibula Osteocutaneous Flap in Reconstruction of Tibial Bone, Soft Tissue, and Main Artery Segmental Defects.

    Science.gov (United States)

    Li, Zonghuan; Yu, Aixi; Qi, Baiwen; Pan, Zhenyu; Ding, Junhui

    2017-08-01

    The aim of this report was to present the use of flow-through free fibula osteocutaneous flap for the repair of complex tibial bone, soft tissue, and main artery segmental defects. Five patients with bone, soft tissue, and segmental anterior tibial artery defects were included. The lengths of injured tibial bones ranged from 4 to 7 cm. The sizes of impaired soft tissues were between 9 × 4 and 15 × 6 cm. The lengths of defect of anterior tibial artery segments ranged from 6 to 10 cm. Two patients had distal limb perfusion problems. Flow-through free fibula osteocutaneous flap was performed for all 5 patients. Patients were followed for 12 to 18 months. All wounds healed after 1-stage operation, and all flow-through flaps survived. The distal perfusion after vascular repair was normal in all patients. Superficial necrosis of flap edge was noted in 1 case. After the local debridement and partial thickness skin graft, the flap healed uneventfully, and the surgical operation did not increase injury to the donor site. Satisfactory bone union was achieved in all patients in 2 to 4 months postoperation. Enlargement of fibula graft was observed during follow-up from 12 to 18 months. The functions of adjacent joints were recovered, and all patients were able to walk normally. Flow-through free fibula osteocutaneous flap was shown to be an effective and efficient technique for repairing composite tibial bone, soft tissue, and main artery segmental defects. This 1-stage operation should be useful in clinical practice for the treatment of complex bone, soft tissue, and vessel defects.

  6. In situ monitoring of localized shear stress and fluid flow within developing tissue constructs by Doppler optical coherence tomography

    Science.gov (United States)

    Jia, Yali; Bagnaninchi, Pierre O.; Wang, Ruikang K.

    2008-02-01

    Mechanical stimuli can be introduced to three dimensional (3D) cell cultures by use of perfusion bioreactor. Especially in musculoskeletal tissues, shear stress caused by fluid flow generally increase extra-cellular matrix (ECM) production and cell proliferation. The relationship between the shear stress and the tissue development in situ is complicated because of the non-uniform pore distribution within the cell-seeded scaffold. In this study, we firstly demonstrated that Doppler optical coherence tomography (DOCT) is capable of monitoring localized fluid flow and shear stress in the complex porous scaffold by examining their variation trends at perfusion rate of 5, 8, 10 and 12 ml/hr. Then, we developed the 3D porous cellular constructs, cell-seeded chitosan scaffolds monitored during several days by DOCT. The fiber based fourier domain DOCT employed a 1300 nm superluminescent diode with a bandwidth of 52 nm and a xyz resolution of 20×20×15 μm in free space. This setup allowed us not only to assess the cell growth and ECM deposition by observing their different scattering behaviors but also to further investigate how the cell attachment and ECM production has the effect on the flow shear stress and the relationship between flow rate and shear stress in the developing tissue construct. The possibility to monitor continuously the constructs under perfusion will easily indicate the effect of flow rate or shear stress on the cell viability and cell proliferation, and then discriminate the perfusion parameters affecting the pre-tissue formation rate growth.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. Spatially Resolved MR-Compatible Doppler Ultrasound: Proof of Concept for Triggering of Diagnostic Quality Cardiovascular MRI for Function and Flow Quantification at 3T.

    Science.gov (United States)

    Crowe, Lindsey Alexandra; Manasseh, Gibran; Chmielewski, Aneta; Hachulla, Anne-Lise; Speicher, Daniel; Greiser, Andreas; Muller, Hajo; de Perrot, Thomas; Vallee, Jean-Paul; Salomir, Rares

    2018-02-01

    We demonstrate the use of a magnetic-resonance (MR)-compatible ultrasound (US) imaging probe using spatially resolved Doppler for diagnostic quality cardiovascular MR imaging (MRI) as an initial step toward hybrid US/MR fetal imaging. A newly developed technology for a dedicated MR-compatible phased array ultrasound-imaging probe acquired pulsed color Doppler carotid images, which were converted in near-real time to a trigger signal for cardiac cine and flow quantification MRI. Ultrasound and MR data acquired simultaneously were interference free. Conventional electrocardiogram (ECG) and the proposed spatially resolved Doppler triggering were compared in 10 healthy volunteers. A synthetic "false-triggered" image was retrospectively processed using metric optimized gating (MOG). Images were scored by expert readers, and sharpness, cardiac function and aortic flow were quantified. Four-dimensional (4-D) flow (two volunteers) showed feasibility of Doppler triggering over a long acquisition time. Imaging modalities were compatible. US probe positioning was stable and comfortable. Image quality scores and quantified sharpness were statistically equal for Doppler- and ECG-triggering (p ). ECG-, Doppler-triggered, and MOG ejection fractions were equivalent (p ), with false-triggered values significantly lower (p 0.05). 4-D flow quantification gave consistent results between ECG and Doppler triggering. We report interference-free pulsed color Doppler ultrasound during MR data acquisition. Cardiovascular MRI of diagnostic quality was successfully obtained with pulsed color Doppler triggering. The hardware platform could further enable advanced free-breathing cardiac imaging. Doppler ultrasound triggering is applicable where ECG is compromised due to pathology or interference at higher magnetic fields, and where direct ECG is impossible, i.e., fetal imaging.

  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. 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)

  15. 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

  16. 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...... (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...... as in the intact blood-perfused arteriole. This indicates that RBCs are not essential for hypoxic vasodilatation. In addition several potential pathways were evaluated. Application of DPCPX (inhibitor of adenosine A1 and A2 receptors) and L-NAME (inhibitor of NO-synthase) did not affect vasomotor responses to low...

  17. The Potential of GMP-Compliant Platelet Lysate to Induce a Permissive State for Cardiovascular Transdifferentiation in Human Mediastinal Adipose Tissue-Derived Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Camilla Siciliano

    2015-01-01

    Full Text Available Human adipose tissue-derived mesenchymal stem cells (ADMSCs are considered eligible candidates for cardiovascular stem cell therapy applications due to their cardiac transdifferentiation potential and immunotolerance. Over the years, the in vitro culture of ADMSCs by platelet lysate (PL, a hemoderivate containing numerous growth factors and cytokines derived from platelet pools, has allowed achieving a safe and reproducible methodology to obtain high cell yield prior to clinical administration. Nevertheless, the biological properties of PL are still to be fully elucidated. In this brief report we show the potential ability of PL to induce a permissive state of cardiac-like transdifferentiation and to cause epigenetic modifications. RTPCR results indicate an upregulation of Cx43, SMA, c-kit, and Thy-1 confirmed by immunofluorescence staining, compared to standard cultures with foetal bovine serum. Moreover, PL-cultured ADMSCs exhibit a remarkable increase of both acetylated histones 3 and 4, with a patient-dependent time trend, and methylation at lysine 9 on histone 3 preceding the acetylation. Expression levels of p300 and SIRT-1, two major regulators of histone 3, are also upregulated after treatment with PL. In conclusion, PL could unravel novel biological properties beyond its routine employment in noncardiac applications, providing new insights into the plasticity of human ADMSCs.

  18. The Potential of GMP-Compliant Platelet Lysate to Induce a Permissive State for Cardiovascular Transdifferentiation in Human Mediastinal Adipose Tissue-Derived Mesenchymal Stem Cells

    Science.gov (United States)

    Bordin, Antonella; Ponti, Donatella; Iudicone, Paola; Rendina, Erino Angelo; Calogero, Antonella; Pierelli, Luca; Ibrahim, Mohsen; De Falco, Elena

    2015-01-01

    Human adipose tissue-derived mesenchymal stem cells (ADMSCs) are considered eligible candidates for cardiovascular stem cell therapy applications due to their cardiac transdifferentiation potential and immunotolerance. Over the years, the in vitro culture of ADMSCs by platelet lysate (PL), a hemoderivate containing numerous growth factors and cytokines derived from platelet pools, has allowed achieving a safe and reproducible methodology to obtain high cell yield prior to clinical administration. Nevertheless, the biological properties of PL are still to be fully elucidated. In this brief report we show the potential ability of PL to induce a permissive state of cardiac-like transdifferentiation and to cause epigenetic modifications. RTPCR results indicate an upregulation of Cx43, SMA, c-kit, and Thy-1 confirmed by immunofluorescence staining, compared to standard cultures with foetal bovine serum. Moreover, PL-cultured ADMSCs exhibit a remarkable increase of both acetylated histones 3 and 4, with a patient-dependent time trend, and methylation at lysine 9 on histone 3 preceding the acetylation. Expression levels of p300 and SIRT-1, two major regulators of histone 3, are also upregulated after treatment with PL. In conclusion, PL could unravel novel biological properties beyond its routine employment in noncardiac applications, providing new insights into the plasticity of human ADMSCs. PMID:26495284

  19. Cardiovascular dysfunction in obesity and new diagnostic imaging techniques: the role of noninvasive image methods.

    Science.gov (United States)

    Barbosa, José Augusto A; Rodrigues, Alexandre B; Mota, Cleonice Carvalho C; Barbosa, Márcia M; Simões e Silva, Ana C

    2011-01-01

    Obesity is a major public health problem affecting adults and children in both developed and developing countries. This condition often leads to metabolic syndrome, which increases the risk of cardiovascular disease. A large number of studies have been carried out to understand the pathogenesis of cardiovascular dysfunction in obese patients. Endothelial dysfunction plays a key role in the progression of atherosclerosis and the development of coronary artery disease, hypertension and congestive heart failure. Noninvasive methods in the field of cardiovascular imaging, such as measuring intima-media thickness, flow-mediated dilatation, tissue Doppler, and strain, and strain rate, constitute new tools for the early detection of cardiac and vascular dysfunction. These techniques will certainly enable a better evaluation of initial cardiovascular injury and allow the correct, timely management of obese patients. The present review summarizes the main aspects of cardiovascular dysfunction in obesity and discusses the application of recent noninvasive imaging methods for the early detection of cardiovascular alterations.

  20. 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.

  1. Effects of flow configuration on bone tissue engineering using human mesenchymal stem cells in 3D chitosan composite scaffolds.

    Science.gov (United States)

    Sellgren, Katelyn L; Ma, Teng

    2015-08-01

    Perfusion bioreactor plays important role in supporting 3D bone construct development. Scaffolds of chitosan composites have been studied to support bone tissue regeneration from osteogenic progenitor cells including human mesenchymal stem cells (hMSC). In this study, porous scaffolds of hydroxyapatite (H), chitosan (C), and gelatin (G) were fabricated by phase-separation and press-fitted in the perfusion bioreactor system where media flow is configured either parallel or transverse with respect to the scaffolds to investigate the impact of flow configuration on hMSC proliferation and osteogenic differentiation. The in vitro results showed that the interstitial flow in the transverse flow (TF) constructs reduced cell growth during the first week of culture but improved spatial cell distribution and early onset of osteogenic differentiation measured by alkaline phosphatase and expression of osteogenic genes. After 14 days of bioreactor culture, the TF constructs have comparable cell number but higher expression of bone markers genes and proteins compared to the parallel flow constructs. To evaluate ectopic bone formation, the HCG constructs seeded with hMSCs pre-cultured under two flow configurations for 7 days were implanted in CD-1 nude mice. While Masson's Trichrom staining revealed bone formation in both constructs, the TF constructs have improved spatial cell and osteoid distribution throughout the 2.0 mm constructs. The results highlight the divergent effects of media flow over the course of construct development and suggest that the flow configuration is an important parameter regulating the cellular events leading to bone construct formation in the HCG scaffolds. © 2014 Wiley Periodicals, Inc.

  2. Emergency repair of upper extremity large soft tissue and vascular injuries with flow-through anterolateral thigh free flaps.

    Science.gov (United States)

    Zhan, Yi; Fu, Guo; Zhou, Xiang; He, Bo; Yan, Li-Wei; Zhu, Qing-Tang; Gu, Li-Qiang; Liu, Xiao-Lin; Qi, Jian

    2017-12-01

    Complex extremity trauma commonly involves both soft tissue and vascular injuries. Traditional two-stage surgical repair may delay rehabilitation and functional recovery, as well as increase the risk of infections. We report a single-stage reconstructive surgical method that repairs soft tissue defects and vascular injuries with flow-through free flaps to improve functional outcomes. Between March 2010 and December 2016 in our hospital, 5 patients with severe upper extremity trauma received single-stage reconstructive surgery, in which a flow-through anterolateral thigh free flap was applied to repair soft tissue defects and vascular injuries simultaneously. Cases of injured artery were reconstructed with the distal trunk of the descending branch of the lateral circumflex femoral artery. A segment of adjacent vein was used if there was a second artery injury. Patients were followed to evaluate their functional recoveries, and received computed tomography angiography examinations to assess peripheral circulation. Two patients had post-operative thumb necrosis; one required amputation, and the other was healed after debridement and abdominal pedicle flap repair. The other 3 patients had no major complications (infection, necrosis) to the recipient or donor sites after surgery. All the patients had achieved satisfactory functional recovery by the end of the follow-up period. Computed tomography angiography showed adequate circulation in the peripheral vessels. The success of these cases shows that one-step reconstructive surgery with flow-through anterolateral thigh free flaps can be a safe and effective treatment option for patients with complex upper extremity trauma with soft tissue defects and vascular injuries. Copyright © 2017. Published by Elsevier Ltd.

  3. A dual flow bioreactor with controlled mechanical stimulation for cartilage tissue engineering

    NARCIS (Netherlands)

    Spitters, Tim; Leijten, Jeroen Christianus Hermanus; Deus, F.D.; Costa, I.B.F.; van Apeldoorn, Aart A.; van Blitterswijk, Clemens; Karperien, Hermanus Bernardus Johannes

    2013-01-01

    In cartilage tissue engineering bioreactors can create a controlled environment to study chondrocyte behavior under mechanical stimulation or produce chondrogenic grafts of clinically relevant size. Here we present a novel bioreactor, which combines mechanical stimulation with a two compartment

  4. 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.

  5. New optical sensing technique of tissue viability and blood flow based on nanophotonic iterative multi-plane reflectance measurements

    Directory of Open Access Journals (Sweden)

    Yariv I

    2016-10-01

    Full Text Available Inbar Yariv,1 Menashe Haddad,2,3 Hamootal Duadi,1 Menachem Motiei,1 Dror Fixler1 1Faculty of Engineering and the Institute of Nanotechnology and Advanced Materials, Bar Ilan University, Ramat Gan, Israel; 2Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel; 3Mayanei Hayeshua Medical Center, Benei Brak, Israel Abstract: Physiological substances pose a challenge for researchers since their optical properties change constantly according to their physiological state. Examination of those substances noninvasively can be achieved by different optical methods with high sensitivity. Our research suggests the application of a novel noninvasive nanophotonics technique, ie, iterative multi-plane optical property extraction (IMOPE based on reflectance measurements, for tissue viability examination and gold nanorods (GNRs and blood flow detection. The IMOPE model combines an experimental setup designed for recording light intensity images with the multi-plane iterative Gerchberg-Saxton algorithm for reconstructing the reemitted light phase and calculating its standard deviation (STD. Changes in tissue composition affect its optical properties which results in changes in the light phase that can be measured by its STD. We have demonstrated this new concept of correlating the light phase STD and the optical properties of a substance, using transmission measurements only. This paper presents, for the first time, reflectance based IMOPE tissue viability examination, producing a decrease in the computed STD for older tissues, as well as investigating their organic material absorption capability. Finally, differentiation of the femoral vein from adjacent tissues using GNRs and the detection of their presence within blood circulation and tissues are also presented with high sensitivity (better than computed tomography to low quantities of GNRs (<3 mg. Keywords: Gerchberg-Saxton, optical properties, gold nanorods, blood vessel, tissue viability

  6. 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

  7. 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...

  8. 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,

  9. Hydro-mechanical foundation for blood swirling vortex flows formation in the cardio-vascular system and the problem of artificial heart creation

    Directory of Open Access Journals (Sweden)

    Sergey G. Chefranov

    2013-11-01

    Full Text Available Leonardo da Vinci perhaps was the first who paid attention to the energetic efficiency of existence of vortices emerging near sines of Valsalva and defining normal functioning (opening of aortal valve. However up to now a fundamental problem of defining of mechanisms of mysterious energetic efficiency of functioning of cardio-vascular system (CVS of blood feeding of the organism is still remaining significantly not solved and this is, for example, one of the main restriction for the creation of artificial heart and corresponding valve systems. In the present paper, results witnessing possible important role of the very hydro-mechanical mechanism in the realization of the noted energetic efficiency of CVS due to formation in the CVS of spiral structural organization of the arterial blood flow observed by methods of MRT and color Doppler-measuring in the left ventricular of the heart and in aorta.

  10. [TISSUE BLOOD FLOW IN THE DIGESTIVE ORGANS OF RATS WITH ACUTE PANCREATITIS AFTER CORVITIN ADMINISTRATION].

    Science.gov (United States)

    Vovkun, T V; Yanchuk, P I; Shtanova, L Y; Shalamay, A S

    2015-01-01

    We have investigated the action of quercetin (in a modified form--Corvitin, BCPP, Ukraine) on the rate of blood flow in the pancreas, liver and gastric mucosa of rats with acute pancreatitis (AP) caused by administration of L-arginine. The rate of blood flow was measured by hydrogen clearance method with electrochemical his generation using Polarographs Lr-9 (Czech Republic). During the first 10 days after modelling of AP in these organs it was observed a gradual decrease compared to the intact animals in the rate of blood flow by 42% (P Corvitin (5 mg/kg, 1 time per day from 11 to 20 days of experiment) in varying degrees promoted to the recovery of the rate of blood flow in all investigated organs: in the pancreas--fully, in the liver--almost entirely and in the gastric mucosa--only partially. Thus, based on obtained results Corvitin can be recommended for partial or complete correction of blood flow disturbances, which arise in the pancreas and other organs of the digestive system in AP. Corvitin can improve the functional state of these organs in the early stages of the disease and accelerate the full restoration of their functions.

  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

    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...... 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...

  12. Continuous flow electrophoretic separation of proteins and cells from mammalian tissues

    Science.gov (United States)

    Hymer, W. C.; Barlow, Grant H.; Blaisdell, Steven J.; Cleveland, Carolyn; Farrington, Mary Ann; Feldmeier, Mary; Hatfield, J. Michael; Lanham, J. Wayne; Grindeland, Richard; Snyder, Robert S.

    1987-01-01

    This paper describes an apparatus for continuous flow electrophoresis (CFE), designed to separate macromolecules and cells at conditions of microgravity. In this CFE, buffer flows upward in a 120-cm long flow chamber, which is 16-cm wide x 3.0-mm thick in the microgravity version (and 6-cm wide x 1.5-mm thick in the unit-gravity laboratory version). Ovalbumin and rat serum albumin were separated in space (flight STS-4) with the same resolution of the two proteins achieved at 25 percent total w/v concentration that was obtained in the laboratory at 0.2 percent w/v concentration. Rat anterior pituitary cells, cultured human embryonic kidney cells, and canine Langerhans cells were separated into subpopulations (flight STS-8) more effectively than in unit gravity, with comparable resolution having been achieved at 100 times the concentration possible on earth.

  13. 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.

  14. Blood flow responses to mild-intensity exercise in ectopic vs. orthotopic prostate tumors; dependence upon host tissue hemodynamics and vascular reactivity.

    Science.gov (United States)

    Garcia, Emmanuel; Becker, Veronika G C; McCullough, Danielle J; Stabley, John N; Gittemeier, Elizabeth M; Opoku-Acheampong, Alexander B; Sieman, Dietmar W; Behnke, Bradley J

    2016-07-01

    Given the critical role of tumor O2 delivery in patient prognosis and the rise in preclinical exercise oncology studies, we investigated tumor and host tissue blood flow at rest and during exercise as well as vascular reactivity using a rat prostate cancer model grown in two transplantation sites. In male COP/CrCrl rats, blood flow (via radiolabeled microspheres) to prostate tumors [R3327-MatLyLu cells injected in the left flank (ectopic) or ventral prostate (orthotopic)] and host tissue was measured at rest and during a bout of mild-intensity exercise. α-Adrenergic vasoconstriction to norepinephrine (NE: 10(-9) to 10(-4) M) was determined in arterioles perforating the tumors and host tissue. To determine host tissue exercise hyperemia in healthy tissue, a sham-operated group was included. Blood flow was lower at rest and during exercise in ectopic tumors and host tissue (subcutaneous adipose) vs. the orthotopic tumor and host tissue (prostate). During exercise, blood flow to the ectopic tumor significantly decreased by 25 ± 5% (SE), whereas flow to the orthotopic tumor increased by 181 ± 30%. Maximal vasoconstriction to NE was not different between arterioles from either tumor location. However, there was a significantly higher peak vasoconstriction to NE in subcutaneous adipose arterioles (92 ± 7%) vs. prostate arterioles (55 ± 7%). Establishment of the tumor did not alter host tissue blood flow from either location at rest or during exercise. These data demonstrate that blood flow in tumors is dependent on host tissue hemodynamics and that the location of the tumor may critically affect how exercise impacts the tumor microenvironment and treatment outcomes. Copyright © 2016 the American Physiological Society.

  15. Blood Flow Changes in Subsynovial Connective Tissue on Contrast-Enhanced Ultrasonography in Patients With Carpal Tunnel Syndrome Before and After Surgical Decompression.

    Science.gov (United States)

    Motomiya, Makoto; Funakoshi, Tadanao; Ishizaka, Kinya; Nishida, Mutsumi; Matsui, Yuichiro; Iwasaki, Norimasa

    2017-11-24

    Although qualitative alteration of the subsynovial connective tissue in the carpal tunnel is considered to be one of the most important factors in the pathophysiologic mechanisms of carpal tunnel syndrome (CTS), little information is available about the microcirculation in the subsynovial connective tissue in patients with CTS. The aims of this study were to use contrast-enhanced ultrasonography (US) to evaluate blood flow in the subsynovial connective tissue proximal to the carpal tunnel in patients with CTS before and after carpal tunnel release. The study included 15 volunteers and 12 patients with CTS. The blood flow in the subsynovial connective tissue and the median nerve was evaluated preoperatively and at 1, 2, and 3 months postoperatively using contrast-enhanced US. The blood flow in the subsynovial connective tissue was higher in the patients with CTS than in the volunteers. In the patients with CTS, there was a significant correlation between the blood flow in the subsynovial connective tissue and the median nerve (P = .01). The blood flow in both the subsynovial connective tissue and the median nerve increased markedly after carpal tunnel release. Our results suggest that increased blood flow in the subsynovial connective tissue may play a role in the alteration of the microcirculation within the median nerve related to the pathophysiologic mechanisms of CTS. The increase in the blood flow in the subsynovial connective tissue during the early postoperative period may contribute to the changes in intraneural circulation, and these changes may lead to neural recovery. © 2017 by the American Institute of Ultrasound in Medicine.

  16. 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...... 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......, 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...

  17. Clarifying tetrapod embryogenesis by a dorso-ventral analysis of the tissue flows during early stages of chicken development.

    Science.gov (United States)

    Fleury, Vincent

    2012-09-01

    The formation of an animal body remains largely a mystery. It is still not clear whether anything like an organization plan or an "archetype" as coined by Darwin himself, actually exists, or whether animals are organized by a succession of stop-and-go genetic, non-linear, instructions with no global pattern. Nevertheless, it was recognized long ago that the early stages of amniote development consist of large scale rotatory movements over a discoidal blastula (Wetzel, 1924). Such rotatory movements reshuffle a mass inside a finite volume, and thus may have to bear physical conservation laws which contribute to establish the plan of animals in a global fashion. In this article I use dual dorso-ventral imaging of the chicken blastula, to show experimentally that the global movement of early vertebrate embryogenesis is organized with a very simple topology, around and away of a series of hyperbolic points in the vector flow of movement. At the first hyperbolic point, a layer of tissue (the mesoderm) ingresses and moves as a viscous sheet radially. It is found that the sheet flows away with a scaling law for the radius R(t)∼exp(t/τ). Also, the movement of this mesoderm changes the flow on the other layer (the ectoderm) by the principle of action and reaction. By mesoderm wetting the ectoderm, the first hyperbolic point migrates from the anal region, to the umbilical region. The final location of the hyperbolic point defines eventually the central part of the body (the umbilical region). Thus, the formation of the vertebrate body is fixed, as a global movement, by the dynamics of singular points in the visco-elastic flow, governed by mechanical forces within the tissue. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  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. Flow cytometric examination of apoptotic effect on brain tissue in postnatal period created by intrauterine oxcarbazepine and gabapentin exposure.

    Science.gov (United States)

    Erisgin, Z; Tekelioglu, Y

    For epileptics, pregnancy contains the balance between no seizure period and antiepileptic use having the least teratogenicity risk. The purpose is to analyse with flow cytometry the apoptotic effects on postnatal brain tissue caused by prenatal use of second generation antiepileptics oxcarbazepine (OXC) and gabapentin (GBP) having different effect mechanisms. 30 (n = 5 each group) Wistar albino male rats (45-days-old) are used. First 3 groups are exposed to OXC (100 mg/kg/day), GBP (50 mg/kg/day), and saline, respectively on the 1st-5th prenatal days (preimplantation-implantation period) while the second 3 groups are exposed to the same substances on the 6th-15th prenatal days (organogenesis), respectively. After sacrifice, brain tissue samples were made into suspension with mechanic and enzymatic digestion and examined with flow cytometry. While apoptosis rate appeared high in rats exposed to OXC on the 1st-5th (p effect in three treatment groups, while difference was not significant for PSS and GBP groups (p = 0.847 and p = 0.934), apoptosis rate was significantly high for OXC on the 6th-15th days compared to the 1st-5th days (p < 0.001). It is observed that the use of OXC causes neurotoxicity during preimplantation, implantation and, especially, organogenesis period (neurogenesis) whereas GBP does not (Fig. 3, Ref. 32).

  20. Cardiovascular magnetic resonance in hypertrophic cardiomyopathy and infiltrative cardiomyopathy

    OpenAIRE

    Schofield, Rebecca; Manacho, Katia; Castelletti, Silvia; Moon, James 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...

  1. 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.

  2. 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.

  3. Multiparametric flow cytometry in the diagnosis and characterization of low-grade pulmonary mucosa-associated lymphoid tissue lymphomas.

    Science.gov (United States)

    Zaer, F S; Braylan, R C; Zander, D S; Iturraspe, J A; Almasri, N M

    1998-06-01

    Primary mucosa associated lymphoid tissue (MALT) lymphomas are rare neoplasms that seem to have a better prognosis than nodal lymphomas. Morphologic diagnosis of these lesions may be difficult because of features that overlap with those of benign lymphoid infiltrates. In this study, we assessed the contribution of multi-parametric flow cytometry in demonstrating clonality and further characterizing pulmonary MALT lymphomas. Based on a clinical or pathologic suspicion of MALT-lymphoma, 3 transbronchial biopsies, 4 fine needle aspirates, 1 core needle biopsy, and 13 wedge excisions of lung were submitted fresh (unfixed) to our laboratory for evaluation. Among the 13 cases diagnosed as MALT lymphomas, B-cell monoclonality was established by identifying expression of a single immunoglobulin light chain on CD20 or CD19-positive cells in 12 cases. One case lacked expression of both light chains on B-cells. Of 11 lymphoma cases in which CD5 and CD10 surface antigens were assessed, no cases expressed CD10, and 1 case demonstrated weak CD5 expression. Nine of 10 cases studied were diploid and 1 case was hyperdiploid. All of the lymphomas displayed low (< or = 3%) S-phase fractions consistent with low grade processes. In 10 patients with short follow-up, none died of their disease and the majority had no evidence of lymphoma dissemination. In seven of the remaining eight cases, B-cells were polyclonal consistent with reactive processes. In one morphologically reactive case, flow cytometric analysis was unsuccessful because of poor cell viability. The pulmonary MALT lymphomas in this study represent a group of B-cell tumors with distinctive morphologic, immunophenotypic, and cell kinetic characteristics. Multi-parametric flow cytometry is useful for confirming B-cell monoclonality and illustrating an antigenic profile compatible with this diagnosis. Flow cytometry can be particularly helpful when working with small biopsies and cytologic samples with limited diagnostic

  4. 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...... decreased gradually to 70% of the control value, indicating hyperventilation. At sea level hyperventilation will not increase brain oxygenation significantly in normal man, as the arterial oxygen content only increases minimally, while CBF is unchanged. At high altitude the beneficial effects...... of acetazolamide on the symptoms of acute mountain sickness may well be due to an improved oxygen supply to the brain, as hyperventilation will, at the low ambient PO2, cause a significant increase of the arterial oxygen content, while CBF presumably is unaffected by the drug. During hypoxia at high altitude...

  5. 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

  6. 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.

  7. Histopathologic and Flow-Cytometric Analysis of Neoplastic and Benign “background” Tissue in Breast Carcinoma Resections

    Directory of Open Access Journals (Sweden)

    Daniel W. Visscher

    1998-01-01

    Full Text Available Two-color, multiparametric synthesis phase fraction (SPF analysis of cytokeratin-labeled epithelial cells was flow cytometrically performed on both benign (SPFb and malignant tissue samples (if available, SPFt from 132 mastectomy/lumpectomy specimens. These data were then correlated with clinicopathologic features, including (1 tumor differentiation, (2 the proportion of tumor comprised of duct carcinoma-in situ (DCIS, and (3 the histology of accompanying benign breast tissue, classified by predominant microscopic pattern as intact, normal terminal duct lobular units (NTDLU, 34% of cases, atrophic (AT, 33% of cases, proliferative fibrocystic (PFC, 26% of cases, and non-proliferative fibrocystic (NPFC, 7% of cases. SPFt was inversely correlated with extent of DCIS (DCIS =0 – 20% tumor volume – 12.7% mean SPFt, vs. DCIS >20% tumor volume – 6.4% mean SPFt, p = 0.001. SPFt also correlated with the histology of background benign breast tissue (NTDLU – 14.8% mean SPFt vs. AT – 6.9% mean SPFt vs. PFC – 12.7% mean SPFt, p = 0.05 but it did not correlate with patient age or SPFb (overall mean =0.73%. SPFb was correlated with patient age (>56 yr – 0.59% mean SPFb vs. < yr – 0.84% mean SPFb, p = 0.02, with background histology (NTDLU – 1.1% mean SPFb vs. AT – 0.43% mean SPFb vs. PFC – 0.70% mean SPFb, p < 0.02 and with the grade of the neoplasm (well/moderate – 0.58% mean vs. poorly differentiated – 0.85% mean, p = 0.04. Patients having a background of PFC were significantly older than patients with a background of NTDLU (45.2 yr vs. 60.2 yr, p = 0.01.

  8. 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

  9. A new approach to improve the specificity of flow-mediated dilation for indicating endothelial function in cardiovascular research.

    Science.gov (United States)

    Atkinson, Greg; Batterham, Alan M; Thijssen, Dick H J; Green, Daniel J

    2013-02-01

    Flow-mediated dilation (FMD) is a noninvasive indicator of endothelial function and is routinely expressed as the percentage change in arterial diameter (FMD%) from a resting baseline (Dbase) to a postischemic peak (Dpeak). This expression is equivalent to the ratio of Dpeak/Dbase and is, therefore, dependent on important statistical assumptions, which have never been analysed in the context of FMD%. We aimed to investigate these assumptions, via a comparison of FMD between samples of children and adults, as well as to explore other approaches to scaling diameter change for Dbase. We found that FMD% did not scale accurately for interindividual differences in Dbase but, as expected, overestimated endothelial function for low Dbase and vice versa. We argue that this imprecise scaling of FMD% is predictable, not explained by physiology and is probably common. This problem is resolved by applying scaling principles, whereby the difference in diameter is the outcome and Dbase is a covariate in a logarithmic-linked generalized linear model. A specific allometric expression of FMD can be derived and we found this to be Dpeak/Dbase rather than a simple ratio in our particular dataset. We found that sample differences in endothelial function were inaccurate with FMD% versus our new allometric approach, and that FMD% misclassified participants into 'high' and 'low'cohorts, which has implications for prognostic-type studies. We conclude that the general use of FMD% could have led to biased comparisons of different conditions and/or populations in past studies. Our new approach to scaling FMD is flexible for different datasets and is not based on the current assumption that a percentage change is appropriate in all circumstances.

  10. 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

  11. 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

  12. 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.

  13. Cardiovascular dysfunction in obesity and new diagnostic imaging techniques: the role of noninvasive image methods

    Directory of Open Access Journals (Sweden)

    Barbosa JA

    2011-05-01

    Full Text Available José Augusto A Barbosa¹, Alexandre B Rodrigues¹, Cleonice Carvalho C Mota¹, Márcia M Barbosa², Ana C Simões e Silva¹¹Department of Pediatrics, Faculty of Medicine, Federal University of Minas Gerais (UFMG, Belo Horizonte, Minas Gerais, Brazil; ²Ecocenter, Socor Hospital, Belo Horizonte, Minas Gerais, BrazilAbstract: Obesity is a major public health problem affecting adults and children in both developed and developing countries. This condition often leads to metabolic syndrome, which increases the risk of cardiovascular disease. A large number of studies have been carried out to understand the pathogenesis of cardiovascular dysfunction in obese patients. Endothelial dysfunction plays a key role in the progression of atherosclerosis and the development of coronary artery disease, hypertension and congestive heart failure. Noninvasive methods in the field of cardiovascular imaging, such as measuring intima-media thickness, flow-mediated dilatation, tissue Doppler, and strain, and strain rate, constitute new tools for the early detection of cardiac and vascular dysfunction. These techniques will certainly enable a better evaluation of initial cardiovascular injury and allow the correct, timely management of obese patients. The present review summarizes the main aspects of cardiovascular dysfunction in obesity and discusses the application of recent noninvasive imaging methods for the early detection of cardiovascular alterations.Keywords: cardiovascular risk, endothelium dysfunction, obesity, strain and strain rate, tissue Doppler

  14. Acoustic radiation force impulse elastography of the kidneys: is shear wave velocity affected by tissue fibrosis or renal blood flow?

    Science.gov (United States)

    Asano, Kenichiro; Ogata, Ai; Tanaka, Keiko; Ide, Yoko; Sankoda, Akiko; Kawakita, Chieko; Nishikawa, Mana; Ohmori, Kazuyoshi; Kinomura, Masaru; Shimada, Noriaki; Fukushima, Masaki

    2014-05-01

    The aim of this study was to identify the main influencing factor of the shear wave velocity (SWV) of the kidneys measured by acoustic radiation force impulse elastography. The SWV was measured in the kidneys of 14 healthy volunteers and 319 patients with chronic kidney disease. The estimated glomerular filtration rate was calculated by the serum creatinine concentration and age. As an indicator of arteriosclerosis of large vessels, the brachial-ankle pulse wave velocity was measured in 183 patients. Compared to the degree of interobserver and intraobserver deviation, a large variance of SWV values was observed in the kidneys of the patients with chronic kidney disease. Shear wave velocity values in the right and left kidneys of each patient correlated well, with high correlation coefficients (r = 0.580-0.732). The SWV decreased concurrently with a decline in the estimated glomerular filtration rate. A low SWV was obtained in patients with a high brachial-ankle pulse wave velocity. Despite progression of renal fibrosis in the advanced stages of chronic kidney disease, these results were in contrast to findings for chronic liver disease, in which progression of hepatic fibrosis results in an increase in the SWV. Considering that a high brachial-ankle pulse wave velocity represents the progression of arteriosclerosis in the large vessels, the reduction of elasticity succeeding diminution of blood flow was suspected to be the main influencing factor of the SWV in the kidneys. This study indicates that diminution of blood flow may affect SWV values in the kidneys more than the progression of tissue fibrosis. Future studies for reducing data variance are needed for effective use of acoustic radiation force impulse elastography in patients with chronic kidney disease.

  15. 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...

  16. In vivo Raman flow cytometry for real-time detection of carbon nanotube kinetics in lymph, blood, and tissues

    Science.gov (United States)

    Biris, Alexandru S.; Galanzha, Ekaterina I.; Li, Zhongrui; Mahmood, Meena; Xu, Yang; Zharov, Vladimir P.

    2009-03-01

    Nanoparticles are intensively being explored as contrast agents for medical diagnostics and therapies using various optical methods. We present the first demonstration of the use of time-resolved Raman spectroscopy for in vivo real-time detection of circulating carbon nanotubes (CNTs) or cancer cells labeled with CNTs in the lymph, blood, and tissues of live animals with fast spectral acquisition times of down to few milliseconds. After intravenously administering CNTs in the tail vein of the rat, this technique provides the ability to detect the circulation of CNTs in the blood microvessels of the intact rat ear. The capability of Raman spectroscopy is also demonstrated to monitor, identify, and image the CNTs during their transportation by lymphatics in the rat ear and mesentery. The strong and specific Raman scattering properties of CNTs make it possible to detect in vitro and in vivo single cancer cells (HeLa) tagged with CNTs. In vivo Raman flow cytometry opens a new avenue for multiparameter analysis of circulating nanoparticles with strong Raman scattering properties and their pharmokinetics in blood and lymph systems. Moreover, this technology has the potential for molecular detection and identification of circulating tumor cells, and infections labeled with CNTs.

  17. 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

    acid, during acute i.v. beta-adrenergic blockade by propranolol, and during continuous i.v. infusion of glucose. The most pronounced lipid mobilization and utilization during work was seen in the control experiments where ATBF rose 3-fold on average from the initial rest period to the third hour...... 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...

  18. 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.

  19. The histology of human right atrial tissue in patients with high-risk Obstructive Sleep Apnea and underlying cardiovascular disease: A pilot study

    Directory of Open Access Journals (Sweden)

    Erik M. van Oosten

    2015-03-01

    Conclusions: In this pilot study there were no observable histological differences in human right atrial tissue from individuals at high- and low-risk for OSA. Further investigation would be required for more definitive results.

  20. 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

  1. 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

  2. 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

  3. 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 sperm morphology and velocity parameters (CASA) rather indicated subtle physiological variations in sperm quality than effects of a local 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.

  4. Correlation between regional cerebral blood flow and degree of brain tissue injury of interictal epileptic activity in patients with epilepsy

    International Nuclear Information System (INIS)

    Ma Huan; Chen Xuehong; Wang Zhengjiang; Ma Dongmei; Feng Jianzhong; Liu Jiangyan

    2011-01-01

    Objective: To explore the correlation between the change of regional cerebral blood flow (rCBF) and brain tissue injury from interictal epileptic activity in patients with epilepsy. Methods: Forty-eight patients with epilepsy and 30 healthy persons were included in the study from which the serum S100β protein levels were determined by double antibody sandwich ELISA method. SPECT rCBF imaging was performed in all patients. The visual and semi-quantitative analyses were used to analyze the epileptic foci. SPSS 11.0 was applied for variance and linear correlation analyses. Results: Serum S-100β in patients with interictal epileptic activity was significantly higher than that in control group ((0.572±0.163) μg/L vs (0.218±0.134) μg/L, t =9.96, P<0.01). According to epilepsy control criteria, 20 cases achieved complete control (CC), 18 cases achieved partial control (PR). However, 10 cases got no improvement,whose serum S-100β protein ((0.809±0.056) μg/L) and the percentage change of rCBF ((0.337±0.060) %) were significantly higher than those of CC ((0.443±0.083) μg/L, (0.035±0.038) %) and those of PC ((0.585±0.108) μg/L, (0.187±0.075)%), F=56. 740, 92. 316, P<0.01. There were high correlation between serum S-100β and the percentage change of rCBF in epilepsy patients (r =0.887, P<0.01). Conclusion: Serum S-100β protein assay combined with rCBF on SPECT imaging can make semi-quantitative diagnosis of epilepsy and help evaluate the brain damage from interictal epileptic activity. (authors)

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

    Science.gov (United States)

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

    2014-01-01

    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 Lifestyle (GOAL)-project addresses whether SAF is related to Systematic COronary Risk Evaluation (SCORE) risk estimation (% 10-year CVD-mortality risk) in overweight/obese persons in primary care, without diabetes/renal disease, and if after 3-year treatment of risk factors (change in, Δ) SAF is related to ΔSCORE. In a sample of 65 participants from the GOAL study, with a body mass index (BMI) >25-40 kg/m2, hypertension and/or dyslipidemia, but without diabetes/renal disease, SAF and CVD risk factors were measured at baseline, and after 3 years of lifestyle and pharmaceutical treatment. At baseline, the mean SCORE risk estimation was 3.1±2.6%, mean SAF 2.04±0.5AU. In multivariate analysis SAF was strongly related to age, but not to other risk factors/SCORE. After 3 years ΔSAF was 0.34±0.45 AU (phistory of CVD compared to 54 persons without CVD (p=0.002). Baseline and 3-year-Δ SAF are not related to (Δ)SCORE, or its components, except age, in the studied population. ΔSAF was negatively related to Δweight. As 3-year SAF was higher in persons with CVD, these results support a larger study on SAF to assess its contribution to conventional risk factors/SCORE in predicting CVD in overweight persons with low-intermediate cardiovascular risk.

  6. Dose-dependent variations in blood flow evaluation of canine nerve, nerve graft, tendon, and ligament tissue by the radiolabeled-microsphere technique

    International Nuclear Information System (INIS)

    Riggi, K.; Wood, M.B.; Ilstrup, D.M.

    1990-01-01

    This study evaluates the dose-dependent accuracy of the radionuclide-labeled microsphere technique for blood flow evaluation in nerve, tendon, and ligament. In eight dogs, blood flows were determined for nerve, nerve graft, tendon, and ligament tissue by simultaneous injection of high- and low-dose microspheres with different radiolabels. The results demonstrated no significant differences in blood flow as measured from the small number of microspheres (less than 400) and the high number (more than 400) for nerve and tendon tissue. For nerve tissue, microsphere counts of 50 to 100, 100 to 200, 200 to 300, and more than 300 produced mean percentage errors of 12.74% (n = 5, SEM = 4.52), 5.45% (n = 13, SEM = 1.22), 10.22% (n = 6, SEM = 4.37), and 17.08% (n = 12, SEM = 3.30), respectively. For tendon tissue, the same microsphere subdivisions had mean percentage errors of 7.47% (n = 4, SEM = 2.66), 3.63% (n = 6, SEM = 1.34), 15.54% (n = 4, SEM = 4.43), and 12.91% (n = 1), respectively. For ligament tissue, percentage errors were consistently higher; microsphere counts of 30 to 100, 100 to 200, and 200 to 300 produced mean errors of 20.14% (n = 4, SEM = 6.38), 18.66% (n = 4, SEM = 6.24), and 25.78% (n = 2, SEM = 1.97), respectively. Although there was no direct relationship between percentage error and number of microspheres retrieved, we suggest that microsphere counts in the range of 100 to 200 should be considered acceptable for nerve and tendon in the canine. Ligament tissue seems to be less well suited to the microsphere technique; however, further study is warranted

  7. 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

  8. 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.

  9. Blood flow MR imaging of the uterine arteries and of normal and malignant cervical tissue. Initial experiences with a 2D-STAR technique

    International Nuclear Information System (INIS)

    Hawighorst, H.; Bock, M.; Knopp, M.V.; Essig, M.; Schoenberg, S.O.; Schad, L.R.; Kaick, G. van; Knapstein, P.G.

    1998-01-01

    Purpose. The aim of this pilot study was to evaluate a 2D-STAR technique as a non contrast-enhanced approach to demonstrate the uterine artery and its branches and to assess the cervical uterine blood flow in healthy volunteers and in patients with advanced uterine cervical carcinoma. Materials and methods. Seven healthy volunteers (mean age, 29 years) and twentytwo patients (mean age, 52 years) with advanced cancer of the uterine cervix (FIGO IIB-IVA) were prospectively examined by 2D-STAR imaging at different inversion delay times (300 ms-1900 ms) which showed the passage of a blood bolus through normal and malignant tissue of the uterine cervix. Results. The uterine artery was well visualized with short inversion delay times of 300 ms to 500 ms. It was characterized as single or multiple helical loops before dividing into its intracervical branches. The intracervical branching was observed at inversion delay times of 500 ms-700 ms. With longer inversion delay times arterial signal enhancement disappeared and cervical tissue enhancement was noted. Enhancement of benign tissue was observed at inversion delay times of 1100 ms-1700 ms, and in malignant tissue at shorter inversion delay times of 900 ms-1300 ms. The maximum of this diffuse signal enhancement of benign tissue was seen at inversion dealy times of 1500 ms (1100 ms-1700 ms), in malignant tissue at significantly (P [de

  10. 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.

  11. 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.

  12. 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

    In vitro experiments have demonstrated that increasing the molar ratio of extracellular non-esterified fatty acids (NEFA) to albumin stimulates thermogenesis in brown adipocytes. To test these results, in vivo blood flow and local temperature were measured in perirenal brown adipose tissue (BAT...... 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...... production was also reduced. Consequently, the increase in whole body oxygen consumption was not due to stimulation of BAT thermogenesis. It is concluded that in vivo assessment of BAT thermogenesis requires concomitant measurements of both local BAT temperature and blood flow....

  13. 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

  14. Cardiovascular diseases

    International Nuclear Information System (INIS)

    Kodama, Kazunori

    1992-01-01

    This paper is aimed to discuss the involvement of delayed radiation effects of A-bomb exposure in cardiovascular diseases. First, the relationship between radiation and cardiovascular diseases is reviewed in the literature. Animal experiments have confirmed the relationship between ionizing radiation and vascular lesions. There are many reports which describe ischemic heart disease, cervical and cerebrovascular diseases, and peripheral disease occurring after radiation therapy. The previous A-bomb survivor cohort studies, i.e., the RERF Life Span Study and Adult Health Study, have dealt with the mortality rate from cardiovascular diseases, the prevalence or incidence of cardiovascular diseases, pathological findings, clinical observation of arteriosclerosis, ECG abnormality, blood pressure abnormality, and cardiac function. The following findings have been suggested: (1) A-bomb exposure is likely to be involved in the mortality rate and incidence of ischemic heart disease and cerebrovascular diseases; (2) similarly, the involvement of A-bomb exposure is considered in the prevalence of the arch of aorta; (3) ECG abnormality corresponding to ischemic heart disease may reflect the involvement of A-bomb exposure. To confirm the above findings, further studies are required on the basis of more accurate information and the appropriate number of cohort samples. Little evidence has been presented for the correlation between A-bomb exposure and both rheumatic heart disease and congenital heart disease. (N.K.) 88 refs

  15. 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

  16. Bizarre (pseudomalignant) granulation-tissue reactions following ionizing-radiation exposure. A microscopic, immunohistochemical, and flow-cytometric study

    International Nuclear Information System (INIS)

    Weidner, N.; Askin, F.B.; Berthrong, M.; Hopkins, M.B.; Kute, T.E.; McGuirt, F.W.

    1987-01-01

    Two patients developed extremely bizarre (pseudomalignant) granulation-tissue reactions in the larynx and facial sinuses, following radiation therapy for carcinoma. Containing pleomorphic spindle cells and numerous (sometimes atypical) mitotic figures, both tumefactive lesions simulated high grade malignancies. While the pleomorphic cells contained vimentin immunoreactivity, they were nonreactive for low or high molecular weight keratin. Flowcytometric study of paraffin-embedded tissues revealed DNA indexes of 0.75 and 1.0. Neither recurred locally nor spread distantly after therapy. Their granulation-tissue growth pattern, and the presence of stromal and endothelial cells showing similar degrees of cytologic atypia were central to their recognition as benign. These findings show that severely atypical, sometimes aneuploid, granulation-tissue reactions can occur following radiation exposure. Care should be taken not to misinterpret these lesions as malignant

  17. 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.

  18. Sequential chimeric medial femoral condyle and anterolateral thigh flow-through flaps for one-stage reconstructions of composite bone and soft tissue defects: Report of three cases.

    Science.gov (United States)

    Henn, Dominic; Abouarab, Mohamed H; Hirche, Christoph; Hernekamp, Jochen F; Schmidt, Volker J; Kneser, Ulrich; Kremer, Thomas

    2017-10-01

    Small recalcitrant non-unions with poor perfusion require reconstruction with vascularized bone flaps. Cases with concomitant large soft tissue defects are especially challenging, since vascularized soft tissue transfer is often indicated and distant microvascular anastomoses may be required. We introduce a sequential chimeric free flap composed of a medial femoral condyle corticoperiosteal flap anastomosed to an anterolateral thigh flow-through flap (MFC-ALT flap) and report its use for reconstruction of small non-unions with concomitant large soft tissue defects in three exemplary patients. Two female and one male patients ages 39-58 years suffered from composite bone and soft tissue defects of the lower extremity and clavicle caused by tumor resection and postoperative radiation resp. infected tibial pilon fracture. The sizes of the soft tissue defects ranged from 15-23 × 4.5-6 cm and the sizes of the bone defects ranged from 1.5-4 × 2-4 cm. Defect reconstructions were performed in all cases with sequential chimeric MFC-ALT flaps with sizes ranging from 2-4 × 1.6-4 cm for the MFC and 21-23 × 7-8 cm for the ALT skin paddles. Functional reconstructions were achieved in all cases resulting in stable unions and soft tissue coverage enabling the patients to bear full weight without assistance on 5-months follow-up. Postoperative course was uneventful and complications were restricted to a small skin necrosis at the suture line in one case. MFC-ALT flaps may be a safe, and effective procedure for one-stage reconstructions of small, irregularly shaped bone defects with concomitant large soft tissue loss or surrounding instable scarring, particularly in cases of recalcitrant non-unions after radiation exposure. © 2017 Wiley Periodicals, Inc.

  19. 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 ...

  20. Trace Elements in Cardiovascular Diseases

    Energy Technology Data Exchange (ETDEWEB)

    Masironi, R. [Cardiovascular Diseases Unit, World Health Organization, Geneva (Switzerland)

    1970-07-01

    Cardiovascular diseases are the leading cause of death in industrialized countries. Their incidence increases, apparently, as a, function of technological progress so that in the future they may become a major public health problem in developing countries too. Early diagnosis and prevention are the tools best suited to curb such an alarming trend, but our knowledge of these topics is unsatisfactory, Valuable information would be obtained through a systematic investigation of trace elements in relation to cardiovascular function and to various types of cardiovascular diseases. Such studies would provide clues to the following questions: 1. Why does the incidence and type of cardiovascular disease differ from one country to another? May this be related to differences in tissue mineral concentrations among various population groups? 2. Which trace elements if any are beneficial to cardiovascular health, and which are harmful ones that may act as aetiological agents for some cardiovascular diseases? 3. Is it possible to utilize measurements of mineral element concentration for diagnostic purposes in cardiovascular disease? (author)

  1. Relationship between level of forage intake, blood flow and oxygen consumption by splanchnic tissues of sheep fed a tropical grass forage.

    Science.gov (United States)

    Hentz, F; Kozloski, G V; Zeni, D; Brun, M V; Stefanello, S

    2017-02-01

    Four Polwarth castrated male sheep (42 ± 4.4 kg live weight (LW) surgically implanted with chronic indwelling catheters into the mesenteric, portal and hepatic veins, housed in metabolism cages and offered Cynodon sp. hay at rates (g of dry matter (DM)/kg LW) of 7, 14, 21 or ad libitum, were used in a 4 × 4 Latin square experiment to evaluate the effect of the level of forage intake on blood flow and oxygen consumption by the portal-drained viscera (PDV), liver and total splanchnic tissues (ST). The portal blood flow and the oxygen consumption by PDV linearly increased at increased organic matter (OM) intake. No effect of level of OM intake was obtained for the hepatic artery blood flow and oxygen consumption by liver. As a consequence, the level of OM intake only tended to directly affect hepatic blood flow and oxygen consumption by total ST. Oxygen consumption was linearly and positively related to blood flow across PDV, liver and total ST. The heat production by PDV and total ST, as proportion of metabolizable energy (ME) intake, decreased curvilinearly at increased ME intake. In conclusion, the oxygen consumption by PDV, but not by liver, was directly related to the level of forage intake by sheep. Moreover, when ingested at levels below maintenance, most of ME was spent as heat produced by ST. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  2. 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

  3. 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.

  4. Stent revascularization restores cortical blood flow and reverses tissue hypoxia in atherosclerotic renal artery stenosis but fails to reverse inflammatory pathways or glomerular filtration rate.

    Science.gov (United States)

    Saad, Ahmed; Herrmann, Sandra M S; Crane, John; Glockner, James F; McKusick, Michael A; Misra, Sanjay; Eirin, Alfonso; Ebrahimi, Behzad; Lerman, Lilach O; Textor, Stephen C

    2013-08-01

    Atherosclerotic renal artery stenosis (ARAS) is known to reduce renal blood flow, glomerular filtration rate (GFR) and amplify kidney hypoxia, but the relationships between these factors and tubulointerstitial injury in the poststenotic kidney are poorly understood. The purpose of this study was to examine the effect of renal revascularization in ARAS on renal tissue hypoxia and renal injury. Inpatient studies were performed in patients with ARAS (n=17; >60% occlusion) before and 3 months after stent revascularization, or in patients with essential hypertension (n=32), during fixed Na(+) intake and angiotensin converting enzyme/angiotensin receptors blockers Rx. Single kidney cortical, medullary perfusion, and renal blood flow were measured using multidetector computed tomography, and GFR by iothalamate clearance. Tissue deoxyhemoglobin levels (R(2)*) were measured by blood oxygen level-dependent MRI at 3T, as was fractional kidney hypoxia (percentage of axial area with R(2)*>30/s). In addition, we measured renal vein levels of neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α. Pre-stent single kidney renal blood flow, perfusion, and GFR were reduced in the poststenotic kidney. Renal vein neutrophil gelatinase-associated lipocalin, tumor necrosis factor-α, monocyte chemoattractant protein-1, and fractional hypoxia were higher in untreated ARAS than in essential hypertension. After stent revascularization, fractional hypoxia fell (Pblood flow, whereas GFR and neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α remained unchanged. These data demonstrate that despite reversal of renal hypoxia and partial restoration of renal blood flow after revascularization, inflammatory cytokines and injury biomarkers remained elevated and GFR failed to recover in ARAS. Restoration of vessel patency alone failed to reverse tubulointerstitial damage and partly

  5. Reduced brachial flow-mediated vasodilation in young adult ex extremely low birth weight preterm: a condition predictive of increased cardiovascular risk?

    Science.gov (United States)

    Bassareo, P P; Fanos, V; Puddu, M; Demuru, P; Cadeddu, F; Balzarini, M; Mercuro, G

    2010-10-01

    Sporadic data present in literature report how preterm birth and low birth weight constitute the risk factors for the development of cardiovascular diseases in later life. To assess the presence of potential alterations to endothelial function in young adults born preterm at extremely low birth weight (Cesarea, Israel). Endothelial function was significantly reduced in ex-ELBW subjects compared to C (1.94 +/- 0.37 vs. 2.68 +/- 0.41, p < 0.0001). Moreover, this function correlated significantly with gestational age (r = 0.56, p < 0.0009) and birth weight (r = 0.63, p < 0.0001). The results obtained reveal a significant decrease in endothelial function of ex-ELBW subjects compared to controls, underlining a probable correlation with preterm birth and low birth weight. Taken together, these results suggest that an ELBW may underlie the onset of early circulatory dysfunction predictive of increased cardiovascular risk.

  6. 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

  7. Relationship Between Kinetics of Inflow and Outflow as the Basis of a Computer Simulation for Solving Compartmental Models: Example of Electrolyte Transfers in Cardiovascular Tissues

    Energy Technology Data Exchange (ETDEWEB)

    Llaurado, J. G. [Biomedical Engineering Group, Marquette University (United States); Marquette School of Medicine, Milwaukee (United States); Nuclear Medicine Service of Veterans Administration Center, Wood, WI (United States)

    1971-02-15

    A method commonly used for the study of the distribution of a substance among the different spaces ol a biological tissue is the continuous washout (outflow) and isotope counting of fragments of tissue previously incubated with a tracer. A first order kinetics compartmental system can be postulated and characterized by the transport rates (k) at which the substance of interest moves across its different compartments. Direct solution from the outflow data requires knowledge of the initial conditions for, or to have access for measurements in, each compartment. This cannot be fulfilled in most biological problems. In the course of studying {sup 22}Na distribution in segments of arteries a digital computer simulation approach was developed to solve the system. In the belief that the approach transcends this particular application, its mathematical basis is herein presented: the movement of radioactive tracer obeys Divides dq/d Divides = - Divides k Divides Divides q Divides + Divides r Divides (1) where |q| is a vector of response functions for each compartment, |k] is a square matrix of transport rate constants and |r| is a vector of input rates to the system. Solution of Eq. 1 is Divides q Divides = e{sup - Divides k Divides t} {integral}{sub 0}{sup t} e{sup Divides k Divides t} Divides r Divides dt + e{sup - Divides k Divides t} Divides q{sub 0} Divides (2) (i) For an inflow experiment, with 0 initial conditions and a constant unit input rate |r{sub u}| Divides q Divides = ( Divides I Divides - e{sup - Divides k Divides t}) Divides k Divides {sup -1} Divides r{sub u} Divides (3) as t --> {infinity}, Divides q{sub {infinity}} Divides = Divides k Divides {sup -1} Divides r{sub u} Divides , which replaced in Eq. 3, Divides q Divides = Divides q{sub {infinity}} Divides -e{sup - Divides k Divides t} Divides q{sub {infinity}} Divides (4) (ii) For an outflow experiment Divides r Divides = 0 and Eq. 2 becomes Divides q Divides = e{sup - Divides k Divides t} Divides q{sub 0

  8. 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...

  9. 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.)

  10. 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.)

  11. Effect of transcervical resection of adhesion combined with low-dose aspirin on uterine artery blood flow and Smad2/3 in endometrial tissue

    Directory of Open Access Journals (Sweden)

    Qian-Wen Chen

    2016-11-01

    Full Text Available Objective: To study the effect of transcervical resection of adhesion combined with lowdose aspirin on uterine artery blood flow and Smad2/3 in endometrial tissue. Methods: A total of 78 patients with severe intrauterine adhesions who received transcervical resection of adhesion in our hospital between June 2012 and October 2014 were prospectively studied and randomly divided into two groups, observation group received postoperative estrogenprogestogen combined with low-dose aspirin therapy, and control group received postoperative estrogen-progestogen therapy. Ultrasound examination was conducted before and after treatment to determine uterine artery and endometrial blood flow parameters, intrauterine adhesion tissue was collected to detect the expression levels of Smad2 and Smad3 as well as downstream molecules, and serum was collected to determine the levels of cytokines. Results: On the ovulation day after 3 cycles of treatment, uterine artery RI and PI of observation group were significantly lower than those of control group, and endometrial VI, FI and VFI were significantly higher than those of control group; uPA expression level in intrauterine adhesion tissue of observation group was significantly higher than that of control group, Smad2, Smad3, PAI-1, ADAM15 and ADAM17 expression levels were significantly lower than those of control group, and serum TGF-β, VEGF, CTGF, IGF-I and TNF-α levels were significantly lower than those of control group. Conclusions: Transcervical resection of adhesion combined with low-dose aspirin therapy can improve the postoperative uterine artery and endometrial blood flow state, inhibit extracellular matrix deposition mediated by Smad2/3 signaling pathway and prevent intrauterine re-adhesion in patients with intrauterine adhesions.

  12. 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.

  13. 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.

  14. 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

    ). Autoregulation was impaired in all of the collaterally perfused areas while the CO2-response always was preserved. Steal phenomena were not seen. In the surrounding brain tissue, autoregulation was normal in 5 patients and impaired in 3 while the CO2-response seemed to be normal. The results confirm...

  15. Development and evaluation of a method for quantitative flow measurement in tissues by means of NMR-tomography

    International Nuclear Information System (INIS)

    Meindl, S.; Seelen, W. von; Hoffmann, K.P.; Emmert, K.

    1985-01-01

    Apart from the known parameters proton density, T1 and T2 the amplitude of an NMR signal is influenced by the movement of the nuclear spins. In NMR-tomography this leads to significant flow-dependent effects appearing differently in the images. Basing on these influences well-defined flow measurement can be carried out using special tomographic measuring programs. The applied phase encoding methods allow such measurements parallel to conventional imaging. Changes in perfusion of defined brain areas caused by neuronal activity were examined with this technique as well as a 2F-2D-glucose-tracer method. (orig.) With 51 refs., 19 figs [de

  16. 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.

  17. Predictive value of reactive hyperemia for cardiovascular events in patients with peripheral arterial disease undergoing vascular surgery.

    Science.gov (United States)

    Huang, Alex L; Silver, Annemarie E; Shvenke, Elena; Schopfer, David W; Jahangir, Eiman; Titas, Megan A; Shpilman, Alex; Menzoian, James O; Watkins, Michael T; Raffetto, Joseph D; Gibbons, Gary; Woodson, Jonathan; Shaw, Palma M; Dhadly, Mandeep; Eberhardt, Robert T; Keaney, John F; Gokce, Noyan; Vita, Joseph A

    2007-10-01

    Reactive hyperemia is the compensatory increase in blood flow that occurs after a period of tissue ischemia, and this response is blunted in patients with cardiovascular risk factors. The predictive value of reactive hyperemia for cardiovascular events in patients with atherosclerosis and the relative importance of reactive hyperemia compared with other measures of vascular function have not been previously studied. We prospectively measured reactive hyperemia and brachial artery flow-mediated dilation by ultrasound in 267 patients with peripheral arterial disease referred for vascular surgery (age 66+/-11 years, 26% female). Median follow-up was 309 days (range 1 to 730 days). Fifty patients (19%) had an event, including cardiac death (15), myocardial infarction (18), unstable angina (8), congestive heart failure (6), and nonhemorrhagic stroke (3). Patients with an event were older and had lower hyperemic flow velocity (75+/-39 versus 95+/-50 cm/s, P=0.009). Patients with an event also had lower flow-mediated dilation (4.5+/-3.0 versus 6.9+/-4.6%, P<0.001), and when these 2 measures of vascular function were included in the same Cox proportional hazards model, lower hyperemic flow (OR 2.7, 95% CI 1.2 to 5.9, P=0.018) and lower flow-mediated dilation (OR 4.2, 95% CI: 1.8 to 9.8, P=0.001) both predicted cardiovascular events while adjusting for other risk factors. Thus, lower reactive hyperemia is associated with increased cardiovascular risk in patients with peripheral arterial disease. Furthermore, flow-mediated dilation and reactive hyperemia incrementally relate to cardiovascular risk, although impaired flow-mediated dilation was the stronger predictor in this population. These findings further support the clinical relevance of vascular function measured in the microvasculature and conduit arteries in the upper extremity.

  18. 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

  19. 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...

  20. Differentiation of human-induced pluripotent stem cell under flow conditions to mature hepatocytes for liver tissue engineering

    DEFF Research Database (Denmark)

    Starokozhko, Viktoriia; Hemmingsen, Mette; Larsen, Layla

    2018-01-01

    Hepatic differentiation of human-induced pluripotent stem cells (hiPSCs) under flow conditions in a 3D scaffold is expected to be a major step forward for construction of bioartificial livers. The aims of this study were to induce hepatic differentiation of hiPSCs under perfusion conditions...... and to perform functional comparisons with fresh human precision-cut liver slices (hPCLS), an excellent benchmark for the human liver in vivo. The majority of the mRNA expression of CYP isoenzymes and transporters and the tested CYP activities, Phase II metabolism, and albumin, urea, and bile acid synthesis...... in the hiPSC-derived cells reached values that overlap those of hPCLS, which indicates a higher degree of hepatic differentiation than observed until now. Differentiation under flow compared with static conditions had a strong inducing effect on Phase II metabolism and suppressed AFP expression but resulted...

  1. Differentiation of human-induced pluripotent stem cell under flow conditions to mature hepatocytes for liver tissue engineering

    DEFF Research Database (Denmark)

    Starokozhko, Viktoriia; Hemmingsen, Mette; Larsen, Layla

    2018-01-01

    and to perform functional comparisons with fresh human precision-cut liver slices (hPCLS), an excellent benchmark for the human liver in vivo. The majority of the mRNA expression of CYP isoenzymes and transporters and the tested CYP activities, Phase II metabolism, and albumin, urea, and bile acid synthesis...... in the hiPSC-derived cells reached values that overlap those of hPCLS, which indicates a higher degree of hepatic differentiation than observed until now. Differentiation under flow compared with static conditions had a strong inducing effect on Phase II metabolism and suppressed AFP expression but resulted...... in slightly lower activity of some of the Phase I metabolism enzymes. Gene expression data indicate that hiPSCs differentiated into both hepatic and biliary directions. In conclusion, the hiPSC differentiated under flow conditions towards hepatocytes express a wide spectrum of liver functions at levels...

  2. Flow cytometric characterization of culture expanded multipotent mesenchymal stromal cells (MSCs) from horse adipose tissue: towards the definition of minimal stemness criteria.

    Science.gov (United States)

    Pascucci, L; Curina, G; Mercati, F; Marini, C; Dall'Aglio, C; Paternesi, B; Ceccarelli, P

    2011-12-15

    In the last decades, multipotent mesenchymal progenitor cells have been isolated from many adult tissues of different species. The International Society for Cellular Therapy (ISCT) has recently established that multipotent mesenchymal stromal cells (MSCs) is the currently recommended designation. In this study, we used flow cytometry to evaluate the expression of several molecules related to stemness (CD90, CD44, CD73 and STRO-1) in undifferentiated, early-passaged MSCs isolated from adipose tissue of four donor horses (AdMSCs). The four populations unanimously expressed high levels of CD90 and CD44. On the contrary, they were unexpectedly negative to CD73. A small percentage of the cells, finally, showed the expression of STRO-1. This last result might be due to the existence of a small subpopulation of STRO-1+ cells or to a poor cross-reactivity of the antibody. A remarkable donor-to-donor consistency and reproducibility of these findings was demonstrated. The data presented herein support the idea that equine AdMSCs may be easily isolated and selected by adherence to tissue culture plastic and exhibit a surface profile characterized by some peculiar differences in comparison to those described in other species. Continued characterization of these cells will help to clarify several aspects of their biology and may ultimately enable the isolation of specific, purified subpopulations. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. 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.

  4. 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

    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...... +/- 3 min on day 0 to 45 +/- 4 min on day 4 (P = 0.019). Neither peak plasma concentration nor area under the curve of insulin aspart changed significantly. CONCLUSIONS: Insertion of a Teflon insulin catheter into the SAT results in increased ATBF and faster absorption of insulin aspart in a period of 4...

  5. 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.

  6. 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.

  7. 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.

  8. Cardiovascular risk and subclinical cardiovascular disease in polycystic ovary syndrome.

    Science.gov (United States)

    Bajuk Studen, Katica; Jensterle Sever, Mojca; Pfeifer, Marija

    2013-01-01

    In addition to its effects on reproductive health, it is now well recognized that polycystic ovary syndrome (PCOS) is a metabolic disorder, characterized by decreased insulin sensitivity which leads to an excess lifetime risk of type 2 diabetes and cardiovascular disease. PCOS patients are often obese, hypertensive, dyslipidemic and insulin resistant; they have obstructive sleep apnea and have been reported to have higher aldosterone levels in comparison to normal healthy controls. These are all components of an adverse cardiovascular risk profile. Many studies exploring subclinical atherosclerosis using different methods (flow-mediated dilatation, intima media thickness, arterial stiffness, coronary artery calcification) as well as assessing circulating cardiovascular risk markers, point toward an increased cardiovascular risk and early atherogenesis in PCOS. The risk and early features of subclinical atherosclerosis can be reversed by non-medical (normalization of weight, healthy lifestyle) and medical (metformin, thiazolidinediones, spironolactone, and statins) interventions. However, the long-term risk for cardiovascular morbidity and mortality as well as the clinical significance of different interventions still need to be properly addressed in a large prospective study. Copyright © 2013 S. Karger AG, Basel.

  9. 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...

  10. 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

  11. Decidual tissue growth and regression in the guinea pig: regulation by uterine blood flow and relation to circulating progesterone concentrations.

    Science.gov (United States)

    Garris, D R

    1984-05-01

    The role of uterine blood flow (UBF) in the modulation of experimentally induced decidua formation was assessed in mature guinea pigs. The response to endometrial trauma, as indexed by uterine weight changes, was dependent upon the type of stimulus used, with deciduogenic effectiveness as follows: saline = oil = knife scratch less than scissor cut. Both the knife scratch and scissor cut techniques induced elevations in UBF compared with control values. Neither uterine weight nor UBF increased when trauma was applied to unresponsive uteri, indicating that inflammation was not the cause of uterine hyperemia. Uterine weight increased from basal levels on the day of trauma (i.e. day 5 of the estrous cycle) to a maximal weight between days 10 and 12 posttrauma. Maximal growth of the induced decidua occurred under conditions of elevated UBF. Subsequently, UBF declined between days 10 and 15 posttrauma, preceding the associate resorption of the induced decidua. During the period of decidua growth, serum progesterone levels were elevated compared with those in control animals. These data indicate that experimentally induced decidua formation in the guinea pig is associated with uterine hyperemia and increased corpus luteum activity, both of which are necessary for proper endometrial differentiation. It is hypothesized that these events mimic the uterine hyperemia associated with blastocyst implanplantation and early placentation in this species.

  12. 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

  13. 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

  14. 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 ...

  15. Advances in cardiovascular fluid mechanics: bench to bedside.

    Science.gov (United States)

    Dasi, Lakshmi P; Sucosky, Philippe; de Zelicourt, Diane; Sundareswaran, Kartik; Jimenez, Jorge; Yoganathan, Ajit P

    2009-04-01

    This paper presents recent advances in cardiovascular fluid mechanics that define the current state of the art. These studies include complex multimodal investigations with advanced measurement and simulation techniques. We first discuss the complex flows within the total cavopulmonary connection in Fontan patients. We emphasize the quantification of energy losses by studying the importance of caval offsets as well as the differences among various Fontan surgical protocols. In our studies of the fluid mechanics of prosthetic heart valves, we reveal for the first time the full three-dimensional complexity of flow fields in the vicinity of bileaflet and trileaflet valves and the microscopic hinge flow dynamics. We also present results of these valves functioning in a patient-specific native aorta geometry. Our in vitro mitral valve studies show the complex mechanism of the native mitral valve apparatus. We demonstrate that the different components of the mitral valve have independent and synergistically complex functions that allow the valve to operate efficiently. We also show how valve mechanics change under pathological and repair conditions associated with enlarged ventricles. Finally, our ex vivo studies on the interactions between the aortic valve and its surrounding hemodynamic environment are aimed at providing insights into normal valve function and valve pathology. We describe the development of organ- and tissue-culture systems and the biological response of the tissue subjected to their respective simulated mechanical environment. The studies noted above have enhanced our understanding of the complex fluid mechanics associated with the cardiovascular system and have led to new translational technologies.

  16. 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).

  17. Subclinical Markers of Cardiovascular Disease Among Police Officers: A Longitudinal Assessment of the Cortisol Awakening Response and Flow Mediated Artery Dilation.

    Science.gov (United States)

    Violanti, John M; Fekedulegn, Desta; Andrew, Michael E; Charles, Luenda E; Gu, Ja K; Miller, Diane B

    2018-05-07

    To examine the association of the cortisol awakening response (CAR) with change in brachial artery flow-mediated dilation (FMD%) in police officers over a seven-year period. Baseline CAR was obtained from four saliva samples taken fifteen minutes apart immediately after awakening. Analysis of covariance was used to compare the change in FMD% (FMD%Follow-up-FMD%Baseline) across tertiles of area under the cortisol curve with respect to increase (AUCI). Regression analysis was use to assess trend. Officers (n = 172; 81% men) had a mean ± SD age of 41 ± 7.6 years. Men in the lowest AUCI tertile (i.e., atypical waking cortisol pattern) had a significantly larger seven-year mean decline in FMD% (mean ± SE: -2.56 ± 0.64) compared to men in the highest tertile (-0.89 ± 0.69) (p = 0.0087). An awakening cortisol AUCI predicted worsening of FMD% approximately seven years later among male officers.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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 ...

  5. APOE Genotyping, Cardiovascular Disease

    Science.gov (United States)

    ... Resources For Health Professionals Subscribe Search APOE Genotyping, Cardiovascular Disease Send Us Your Feedback Choose Topic At a ... help understand the role of genetic factors in cardiovascular disease . However, the testing is sometimes used in clinical ...

  6. 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 ... clear that there is a strong correlation between cardiovascular disease (CVD) and diabetes. At least 68 percent ...

  7. Space research on organs and tissues

    Science.gov (United States)

    Tischler, Marc E.; Morey-Holton, Emily

    1993-01-01

    Studies in space on various physiological systems have and will continue to provide valuable information on how they adapt to reduced gravitational conditions, and how living in a 1 g (gravity) environment has guided their development. Muscle and bone are the most notable tissues that respond to unweighting caused by lack of gravity. The function of specific muscles and bones relates directly to mechanical loading, so that removal of 'normal forces' in space, or in bedridden patients, causes dramatic loss of tissue mass. The cardiovascular system is also markedly affected by reduced gravity. Adaptation includes decreased blood flow to the lower extremities, thus decreasing the heart output requirement. Return to 1 g is associated with a period of reconditioning due to the deconditioning that occurs in space. Changes in the cardiovascular system are also related to responses of the kidney and certain endocrine (hormone-producing) organs. Changes in respiratory function may also occur, suggesting an effect on the lungs, though this adaptation is poorly understood. The neurovestibular system, including the brain and organs of the inner ear, must adapt to the disorientation caused by lack of gravity. Preliminary findings have been reported for liver. Additionally, endocrine organs responsible for release of hormones such as insulin, growth hormone, glucocorticoids, and thyroid hormone may respond to spaceflight.

  8. Association between Serum Osteopontin Levels and Cardiovascular Risk in Hypothyrodism

    OpenAIRE

    Türkan Mete; Gülhan Duman; Eda Melek Ertörer; Emre Bozkırlı; Okan Sefa Bakıner; Neslihan Başçıl Tütüncü

    2016-01-01

    Purpose: Cardiovascular effects of hypothyroidism are well known. Osteopontin (OPN) is a new inflammatory marker which was first isolated from the bone. Flow-mediated dilatation (FMD), a noninvasive technique to measure this endothelium-dependent function, has been used in several clinical studies to show cardiovascular risks. The aim of our study was to assess FMD value in hypothyroidism patients and to investigate whether plasma OPN level is a parameter which can predict cardiovascular risk...

  9. Cardiovascular responses to treadmill exercise in Nigerian ...

    African Journals Online (AJOL)

    2011-07-25

    Jul 25, 2011 ... The systolic blood pressure (SBP) and pressure rate product (PRP) ... Left ventricular hypertrophy (LVH) has been shown to be ... and functional evaluation of patients with cardiovascular ... excursion of the mitral valve leaflets. ..... blood flow reflecting diastolic behavior of the left ventricle in health and.

  10. 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.

  11. 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.

  12. 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....

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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...

  19. Cardiovascular effects. Chapter 3.1

    International Nuclear Information System (INIS)

    Lecomte, J.

    1975-01-01

    The cardiovascular effects of various radioprotective substances are reviewed. Reports of the cardiovascular reactions of different species have been analysed to show that there is no relationship between the principal cardiovascular activities and the specific effects of the radioprotective agents; sometimes radioprotection develops simultaneously with a general lowering of arterial pressure, sometimes it occurs with a rise in blood pressure. In contrast, lowered arterial pressure in the chicken is not sufficient to raise the resistance to X-rays. No common characteristics were revealed by a comparative study of the effects of radioprotective agents on blood pressure, histamine liberation and concentration of catecholamines in blood. The effect on tissue perfusion, at the level of the microcirculation, may be of more significance, but techniques are not yet available for investigating the mechanism of action at this level. (U.K.)

  20. 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...

  1. Qualitative analysis of intracranial CSF flow on cine-MR imaging, with special reference to signal ratio of CSF to fat tissue

    International Nuclear Information System (INIS)

    Kadowaki, Chikafusa; Hara, Mitsuhiro; Numoto, Mitsuo; Takeuchi, Kazuo; Saito, Isamu

    1993-01-01

    Cine magnetic resonance images (MR) dramatically demonstrate the pulsatile flow of cerebrospinal fluid (CSF) stimulated by the pulsatile motion of the brain following cardiac pulsation. Reduced signal intensity, frequently observed especially in the aqueduct of Sylvius, the third ventricle and the fourth ventricle, is believed to reflect the pulsatile motion of the CSF. Qualitative analysis of MR signal intensity of CSF on each cine frame is compared with CSF flow within the ventricles on real-time cine MR images. While the chronological changes in signal intensities of CSF within the ventricles show only marginal changes in signal intensity in the third ventricle related to downward flow of CSF passing through the foramen of Monro during the early stage of cardiac systole, these changes are thought to have no significant correlation with the CSF flow in the CSF pathway. The chronological changes in relative signal ratios, SR [signal intensities of CSF/signal intensities of fat] can show CSF flow and turbulence within the ventricles. Under normal conditions, within the third ventricle the SR decreases due to pulsatile CSF flow through the foramen of Monro during the early stage of cardiac systole, and decreases because of the flow of CSF from the anterior to the posterior part of the third ventricle, the downward flow of CSF through the aqueduct leads to a lower SR during cardiac diastole. These changes in the fourth ventricle are stimulated by the changes in SR in the third ventricle. The new method of analyzing chronological changes in the relative MR signal ratio of CSF to fat [SR] has the distinct advantage of providing an accurate evaluation of CSF dynamics, and it provides us with important diagnostic information leading to clarification of the pathophysiology of CSF dynamics. (author)

  2. 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....

  3. 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....

  4. 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.

  5. Molecular cardiovascular imaging

    International Nuclear Information System (INIS)

    Schaefers, M.

    2007-01-01

    Although huge and long-lasting research efforts have been spent on the development of new diagnostic techniques investigating cardiovascular diseases, still fundamental challenges exist; the main challenge being the diagnosis of a suspected or known coronary artery disease or its consequences (myocardial infarction, heart failure etc.). Beside morphological techniques, functional imaging modalities are available in clinical diagnostic algorithms, whereas molecular cardiovascular imaging techniques are still under development. This review summarizes clinical-diagnostical challenges of modern cardiovascular medicine as well as the potential of new molecular imaging techniques to face these. (orig.)

  6. 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...

  7. Cardiovascular Disease in Acromegaly.

    Science.gov (United States)

    Sharma, Morali D; Nguyen, Anh V; Brown, Spandana; Robbins, Richard J

    2017-01-01

    In patients with acromegaly, chronic excess of growth hormone (GH) and insulin-like growth factor-1 (IGF-1) leads to the development of acromegalic cardiomyopathy. Its main features are biventricular hypertrophy, diastolic dysfunction, and in later stages, systolic dysfunction and congestive heart failure. Surgical and/or pharmacological treatment of acromegaly and control of cardiovascular risk factors help reverse some of these pathophysiologic changes and decrease the high risk of cardiovascular complications.

  8. Intracranial CSF flow on cine-MR. 2. Qualitative analysis in CSF dynamics by MR signal ratio of CSF to fat tissue in healthy subjects and patients with aqueduct stenosis

    International Nuclear Information System (INIS)

    Kadowaki, Chikafusa; Hara, Mitsuhiro; Takeuchi, Kazuo; Saito, Isamu

    1994-01-01

    Changes in MR signal intensities (SIs) of CSF and relative MR signal ratios (SRs) of intraventricular CSF to fat tissue were evaluated in 5 healthy adults on cine MR images during a cardiac cycle in a study of normal intracranial CSF dynamics. The altered patterns of MR SIs and SRs in 6 patients with aqueduct stenosis were compared with normal CSF flow patterns in a demonstration of CSF dynamics changes. MR SIs of CSF within the ventricles were measured on each cine image obtained by cardiac gated, multiframe, cine MR imaging. Chronological changes in MR SIs and SRs during a cardiac cycle were compared with the actual CSF flow visualized on real cine images. In normal CSF circulation, MR SIs of CSF within the ventricles were reduced quickly following an R-wave on ECG to 15% of the R-R interval, after which SIs fluctuated slightly. These changes in MR SIs of CSF could only be related to the pulsatile CSF flow through the foramen of Monro into the anterior part of the third ventricle during early cardiac systole. MR SRs of CSF to fat tissue fluctuated according to the actual CSF flow within the ventricles during a cardiac cycle. MR SRs in the third ventricle decreased to 20-30% of the R-R interval following the R-wave due to downward CSF flow during early cardiac systole, and decreased again from late cardiac systole to diastole due to caudal CSF flow in the third ventricle. In the fourth ventricle, MR SRs of CSF decreased to 60-80% of the R-R interval because of the CSF flow through the aqueduct during cardiac diastole. In patients with aqueduct stenosis, MR SRs of CSF within the ventricles fluctuated randomly, and the amplitude of MR SRs was also greater than in subjects with a patent aqueduct. These changes were identified as turbulence and stagnation due to obstruction in the CSF pathway. Analysis of chronological changes in MR signal ratios of CSF to fat is useful in demonstrating the pathophysiologic features of intracranial CSF dynamics. (author) 52 refs

  9. 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.

  10. A randomized, controlled, double-blind crossover study on the effects of 2-L infusions of 0.9% saline and plasma-lyte® 148 on renal blood flow velocity and renal cortical tissue perfusion in healthy volunteers.

    Science.gov (United States)

    Chowdhury, Abeed H; Cox, Eleanor F; Francis, Susan T; Lobo, Dileep N

    2012-07-01

    We compared the effects of intravenous infusions of 0.9% saline ([Cl] 154 mmol/L) and Plasma-Lyte 148 ([Cl] 98 mmol/L, Baxter Healthcare) on renal blood flow velocity and perfusion in humans using magnetic resonance imaging (MRI). Animal experiments suggest that hyperchloremia resulting from 0.9% saline infusion may affect renal hemodynamics adversely, a phenomenon not studied in humans. Twelve healthy adult male subjects received 2-L intravenous infusions over 1 hour of 0.9% saline or Plasma-Lyte 148 in a randomized, double-blind manner. Crossover studies were performed 7 to 10 days apart. MRI scanning proceeded for 90 minutes after commencement of infusion to measure renal artery blood flow velocity and renal cortical perfusion. Blood was sampled and weight recorded hourly for 4 hours. Sustained hyperchloremia was seen with saline but not with Plasma-Lyte 148 (P Blood volume changes were identical (P = 0.867), but there was greater expansion of the extravascular fluid volume after saline (P = 0.029). There was a significant reduction in mean renal artery flow velocity (P = 0.045) and renal cortical tissue perfusion (P = 0.008) from baseline after saline, but not after Plasma-Lyte 148. There was no difference in concentrations of urinary neutrophil gelatinase-associated lipocalin after the 2 infusions (P = 0.917). This is the first human study to demonstrate that intravenous infusion of 0.9% saline results in reductions in renal blood flow velocity and renal cortical tissue perfusion. This has implications for intravenous fluid therapy in perioperative and critically ill patients. NCT01087853.

  11. 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.

  12. 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.

  13. 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.

  14. 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

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

    Science.gov (United States)

    Skomudek, Aleksandra; Gilowska, Iwona; Jasiński, Ryszard; Rożek-Piechura, Krystyna

    2017-01-01

    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. 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. 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. Research results showed that the temperature distribution and the dynamics of blood flow are not significantly different between the right and left extremities in both males and females. However, significant temperature differences were found between the gender groups. Significantly higher temperature values in both the right and left extremities were recorded in males than in females.

  16. 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

  17. Enjoying hobbies is related to desirable cardiovascular effects.

    Science.gov (United States)

    Saihara, Keishi; Hamasaki, Shuichi; Ishida, Sanemasa; Kataoka, Tetsuro; Yoshikawa, Akiko; Orihara, Koji; Ogawa, Masakazu; Oketani, Naoya; Fukudome, Tsuyoshi; Atsuchi, Nobuhiko; Shinsato, Takuro; Okui, Hideki; Kubozono, Takuro; Ichiki, Hitoshi; Kuwahata, So; Mizoguchi, Etsuko; Fujita, Shoji; Takumi, Takuro; Ninomiya, Yuichi; Tomita, Kaai; Tei, Chuwa

    2010-03-01

    An unhealthy lifestyle can increase the risk of cardiovascular disease. However, the mechanism by which lifestyle influences the development of cardiovascular disease remains unclear. Since coronary endothelial function is a predictor of cardiovascular prognosis, the goal of this study was to characterize the effect of enjoying hobbies on coronary endothelial function and cardiovascular outcomes. A total of 121 consecutive patients (76 men, 45 women) with almost normal coronary arteries underwent Doppler flow study of the left anterior descending coronary artery following sequential administration of papaverine, acetylcholine, and nitroglycerin. On the basis of responses to questionnaires, patients were divided into two groups; the Hobby group (n = 71) who enjoyed hobbies, and the Non-hobby group (n = 50) who had no hobbies. Cardiovascular outcomes were assessed at long-term follow-up using medical records or questionnaire surveys for major adverse cardiovascular events (MACE).The average follow-up period was 916 +/- 515 days. There were no significant differences in demographics when comparing the two groups. The percent change in coronary blood flow and coronary artery diameter induced by acetylcholine was significantly greater in the Hobby group than in the Non-hobby group (49% +/- 77% vs 25% +/- 37%, P hobbies was the only independent predictor of MACE (odds ratio 8.1 [95% confidence interval 1.60, 41.90], P = 0.01) among the variables tested. In the early stages of arteriosclerosis, enjoying hobbies may improve cardiovascular outcomes via its favorable effects on coronary endothelial function.

  18. 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

    , and there was a relationship between ScO2 and forehead skin blood flow (Pearson r = 0.55, P = 0.042, 95% confidence interval [CI], = 0.025-0.84; Spearman r = 0.81, P Pearson r = 0.62, P = 0.019, 95% CI, 0.13 to 0.86; Spearman r = 0.64, P = 0.012, 95% CI, 0...

  19. 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.

  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. 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

    in 0.1 ml isotonic saline injected into the subcutaneous adipose tissue in the forefoot. The detector is connected to a memory unit allowing for storage of data. Due to the short distance, the recorded elimination rate constant must be corrected for combined convection and diffusion of the radioactive...... within normal range. SBF during day-time activities decreased by up to 50% postoperatively. This is caused by the reappearance of the local, sympathetic, veno-arteriolar vasoconstrictor response. During sleep SBF increased by 71%. The term postreconstructive hyperaemia seems improper, at least in a long-term...

  2. 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...

  3. 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...... National Patient Register was used to defining the first date of experiencing a cardiovascular event by means of a discharge diagnosis and/or having performed a coronary bypass operation or revascularization of the coronary arteries. The proportion of patients with already established CVD at the diagnosis...

  4. Mannan-Binding Lectin in Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Izabela Pągowska-Klimek

    2014-01-01

    Full Text Available Cardiovascular disease remains the leading cause of mortality and morbidity worldwide so research continues into underlying mechanisms. Since innate immunity and its potent component mannan-binding lectin have been proven to play an important role in the inflammatory response during infection and ischaemia-reperfusion injury, attention has been paid to its role in the development of cardiovascular complications as well. This review provides a general outline of the structure and genetic polymorphism of MBL and its role in inflammation/tissue injury with emphasis on associations with cardiovascular disease. MBL appears to be involved in the pathogenesis of atherosclerosis and, in consequence, coronary artery disease and also inflammation and tissue injury after myocardial infarction and heart transplantation. The relationship between MBL and disease is rather complex and depends on different genetic and environmental factors. That could be why the data obtained from animal and clinical studies are sometimes contradictory proving not for the first time that innate immunity is a “double-edge sword,” sometimes beneficial and, at other times disastrous for the host.

  5. Cardiovascular risk calculation

    African Journals Online (AJOL)

    James A. Ker

    2014-08-20

    Aug 20, 2014 ... smoking and elevated blood sugar levels (diabetes mellitus). These risk ... These are risk charts, e.g. FRS, a non-laboratory-based risk calculation, and ... for hard cardiovascular end-points, such as coronary death, myocardial ...

  6. 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

  7. 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...

  8. 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...

  9. 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...

  10. 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 ... and procedures related to heart disease and stroke. Cardiovascular Conditions • Conditions Home • Arrhythmia and Atrial Fibrillation • Cardiac ...

  11. Nutrition and cardiovascular health.

    Science.gov (United States)

    Berciano, Silvia; Ordovás, José M

    2014-09-01

    A multitude of studies have been published on the relationship between cardiovascular disease risk and a variety of nutrients, foods, and dietary patterns. Despite the well-accepted notion that diet has a significant influence on the development and prevention of cardiovascular disease, the foods considered healthy and harmful have varied over the years. This review aims to summarize the current scientific evidence on the cardioprotective effect of those foods and nutrients that have been considered healthy as well as those that have been deemed unhealthy at any given time in history. For this purpose, we reviewed the most recent literature using as keywords foods and nutrients (ie, meat, omega-3) and cardiovascular disease-related terms (ie, cardiovascular diseases, stroke). Emphasis has been placed on meta-analyses and Cochrane reviews. In general, there is a paucity of intervention studies with a high level of evidence supporting the benefits of healthy foods (ie, fruits and vegetables), whereas the evidence supporting the case against those foods considered less healthy (ie, saturated fat) seems to be weakened by most recent evidence. In summary, most of the evidence supporting the benefits and harms of specific foods and nutrients is based on observational epidemiological studies. The outcome of randomized clinical trials reveals a more confusing picture with most studies providing very small effects in one direction or another; the strongest evidence comes from dietary patterns. The current status of the relationship between diet and cardiovascular disease risk calls for more tailored recommendations based on genomic technologies. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

  12. S.E. Mitchell Vascular Anomalies Flow Chart (SEMVAFC): A visual pathway combining clinical and imaging findings for classification of soft-tissue vascular anomalies

    International Nuclear Information System (INIS)

    Tekes, A.; Koshy, J.; Kalayci, T.O.; Puttgen, K.; Cohen, B.; Redett, R.; Mitchell, S.E.

    2014-01-01

    Classification of vascular anomalies (VAs) is challenging due to overlapping clinical symptoms, confusing terminology in the literature and unfamiliarity with this complex entity. It is important to recognize that VAs include two distinct entities, vascular tumours (VTs) and vascular malformations (VaMs). In this article, we describe SE Mitchell Vascular Anomalies Flow Chart (SEMVAFC), which arises from a multidisciplinary approach that incorporates clinical symptoms, physical examination and magnetic resonance imaging (MRI) findings to establish International Society for the Study of Vascular Anomalies (ISSVA)-based classification of the VAs. SEMVAFC provides a clear visual pathway for physicians to accurately diagnose Vas, which is important as treatment, management, and prognosis differ between VTs and VaMs

  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. 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....

  15. 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- ...

  16. 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)

  17. Cyclooxygenase-2 Selectively Controls Renal Blood Flow Through a Novel PPARβ/δ-Dependent Vasodilator Pathway.

    Science.gov (United States)

    Kirkby, Nicholas S; Sampaio, Walkyria; Etelvino, Gisele; Alves, Daniele T; Anders, Katie L; Temponi, Rafael; Shala, Fisnik; Nair, Anitha S; Ahmetaj-Shala, Blerina; Jiao, Jing; Herschman, Harvey R; Xiaomeng, Wang; Wahli, Walter; Santos, Robson A; Mitchell, Jane A

    2018-02-01

    Cyclooxygenase-2 (COX-2) is an inducible enzyme expressed in inflammation and cancer targeted by nonsteroidal anti-inflammatory drugs. COX-2 is also expressed constitutively in discreet locations where its inhibition drives gastrointestinal and cardiovascular/renal side effects. Constitutive COX-2 expression in the kidney regulates renal function and blood flow; however, the global relevance of the kidney versus other tissues to COX-2-dependent blood flow regulation is not known. Here, we used a microsphere deposition technique and pharmacological COX-2 inhibition to map the contribution of COX-2 to regional blood flow in mice and compared this to COX-2 expression patterns using luciferase reporter mice. Across all tissues studied, COX-2 inhibition altered blood flow predominantly in the kidney, with some effects also seen in the spleen, adipose, and testes. Of these sites, only the kidney displayed appreciable local COX-2 expression. As the main site where COX-2 regulates blood flow, we next analyzed the pathways involved in kidney vascular responses using a novel technique of video imaging small arteries in living tissue slices. We found that the protective effect of COX-2 on renal vascular function was associated with prostacyclin signaling through PPARβ/δ (peroxisome proliferator-activated receptor-β/δ). These data demonstrate the kidney as the principle site in the body where local COX-2 controls blood flow and identifies a previously unreported PPARβ/δ-mediated renal vasodilator pathway as the mechanism. These findings have direct relevance to the renal and cardiovascular side effects of drugs that inhibit COX-2, as well as the potential of the COX-2/prostacyclin/PPARβ/δ axis as a therapeutic target in renal disease. © 2018 The Authors.

  18. [Strategies for cardiovascular disease prevention].

    Science.gov (United States)

    Gabus, Vincent; Wuerzner, Grégoire; Saubade, Mathieu; Favre, Lucie; Jacot Sadowski, Isabelle; Nanchen, David

    2018-02-28

    Atherosclerosis is a disease which develops very gradually over decades. Under the influence of modifiable cardiovascular risk factors, such as blood pressure, LDL-cholesterol level, smoking or lifestyle, clinical symptoms of atherosclerosis manifest more or less early in life. When cardiovascular risk factors accumulate, the risk of having a cardiovascular event increases and the benefits of prevention measures are greater. This article summarizes existing strategies for controlling modifiable cardiovascular risk factors in primary prevention. The physician can rely on an interprofessional network of cardiovascular prevention. Managing risk factors while respecting the autonomy and priorities of the patient will bring the greatest benefit.

  19. 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)

  20. Cardiovascular manifestations of Alkaptonuria.

    Science.gov (United States)

    Pettit, Stephen J; Fisher, Michael; Gallagher, James A; Ranganath, Lakshminarayan R

    2011-12-01

    The cardiovascular manifestations of alkaptonuria relate to deposition of ochronotic pigment within heart valves, endocardium, aortic intima and coronary arteries. We assessed 16 individuals with alkaptonuria for cardiovascular disease, including full electrocardiographic and echocardiographic assessment. The self reported prevalence of valvular heart disease and coronary artery disease was low. There was a significant burden of previously undiagnosed aortic valve disease, reaching a prevalence of over 40% by the fifth decade of life. The aortic valve disease was found to increase in both prevalence and severity with advancing age. In contrast to previous reports, we did not find a significant burden of mitral valve disease or coronary artery disease. These findings are important for the clinical follow-up of patients with alkaptonuria and suggest a role for echocardiographic surveillance of patients above 40 years old.

  1. 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.

  2. Slow breathing and cardiovascular disease

    Directory of Open Access Journals (Sweden)

    Ashish Chaddha

    2015-01-01

    Full Text Available Cardiovascular disease is the leading cause of death for both men and women worldwide. Much emphasis has been placed on the primary and secondary prevention of cardiovascular disease. While depression and anxiety increase the risk of developing cardiovascular disease, cardiovascular disease also increases the risk of developing anxiety and depression. Thus, promoting optimal mental health may be important for both primary and secondary prevention of cardiovascular disease. Like lowering blood pressure, lipids, and body weight, lowering anger and hostility and improving depression and anxiety may also be an important intervention in preventive cardiology. As we strive to further improve cardiovascular outcomes, the next bridge to cross may be one of offering patients nonpharmacologic means for combating daily mental stress and promoting mental health, such as yoga and pranayama. Indeed, the best preventive cardiovascular medicine may be a blend of both Western and Eastern medicine.

  3. 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...

  4. Cardiovascular safety of etoricoxib

    Directory of Open Access Journals (Sweden)

    Viktoriya Georgievna Barskova

    2011-01-01

    Full Text Available Meticulous attention is paid to the cardiovascular safety of nonsteroidal anti-inflammatory drugs (NSAIDs, the so-called selective cyclooxy-genase 2 (COX-2 inhibitors in particular. The author considers precisely this matter in case of Russia's recent NSAID etoricoxib that has been tested along with other most studied medications from this group, by applying one of the latest meta-analyses. The EULAR recommendations to use NSAIDs are given.

  5. Nutritional habits & cardiovascular disease

    OpenAIRE

    Sampaio, Hélia; Capitão, Sandra; Ferro-Lebres, Vera

    2010-01-01

    An elevated predominance of the risk factors associated to the illnesses of the circulatory system, particurily hypercholesterolemia and arterial hypertension aim for a special attention to its prevention. This way, the composition of the digested food daily can influence the sprouting of Cardiovascular Disease (CVD), which has shown association between the risk factors and the things we consume. The present study had an objective to identify the influential factors of social economics...

  6. Cocoa and cardiovascular health

    OpenAIRE

    Corti, R; Flammer, A J; Hollenberg, N K; Lüscher, T F

    2009-01-01

    Epidemiological data demonstrate that regular dietary intake of plant-derived foods and beverages reduces the risk of coronary heart disease and stroke. Among many ingredients, cocoa might be an important mediator. Indeed, recent research demonstrates a beneficial effect of cocoa on blood pressure, insulin resistance, and vascular and platelet function. Although still debated, a range of potential mechanisms through which cocoa might exert its benefits on cardiovascular health have been propo...

  7. [Thyroid and cardiovascular disorders].

    Science.gov (United States)

    Zyśko, Dorota; Gajek, Jacek

    2004-05-01

    In this study three problems concerning interactions between thyroid and cardiovascular system are discussed. Cardiac arrhythmias, congestive heart failure, pleural effusion, hyperlipidaemia, arterial hypertension may be consequences of thyroid disorders leading to inappropriate hormone secretion. During such illnesses as heart failure, myocardial infarction and in patients undergoing coronary artery bypass surgery profound changes may occur in thyroid hormone metabolism known as sick euthyroid syndrome. Treatment with amiodarone may lead to changes in thyroid tests results and to development of hypothyroidism or thyrotoxicosis.

  8. 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

  9. Psoriasis and cardiovascular events

    DEFF Research Database (Denmark)

    Raaby, Line; Ahlehoff, Ole; de Thurah, Annette

    2017-01-01

    So far, systematic reviews have suggested an increased risk of cardiovascular diseases (CVD) in psoriatic patients, though some results have been conflicting. The aim of this study was to update the current level of evidence through a systematic search in MEDLINE, EMBASE and Cochrane Central...... 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...

  10. Tissue types (image)

    Science.gov (United States)

    ... are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue supports ... binds them together (bone, blood, and lymph tissues). Epithelial tissue provides a covering (skin, the linings of the ...

  11. 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.

  12. Trends in Tissue Engineering for Blood Vessels

    Directory of Open Access Journals (Sweden)

    Judee Grace Nemeno-Guanzon

    2012-01-01

    Full Text Available 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.

  13. Molecular imaging in cardiovascular diseases

    International Nuclear Information System (INIS)

    Botnar, R.M.; Ebersberger, H.; Noerenberg, D.

    2015-01-01

    Cardiovascular diseases remain the leading cause of morbidity and mortality in industrialized and developing countries. In clinical practice, the in-vivo identification of atherosclerotic lesions, which can lead to complications such as heart attack or stroke, remains difficult. Imaging techniques provide the reference standard for the detection of clinically significant atherosclerotic changes in the coronary and carotid arteries. The assessment of the luminal narrowing is feasible, while the differentiation of stable and potentially unstable or vulnerable atherosclerotic plaques is currently not possible using non-invasive imaging. With high spatial resolution and high soft tissue contrast, magnetic resonance imaging (MRI) is a suitable method for the evaluation of the thin arterial wall. In clinical practice, native MRI of the vessel wall already allows the differentiation and characterization of components of atherosclerotic plaques in the carotid arteries and the aorta. Additional diagnostic information can be gained by the use of non-specific MRI contrast agents. With the development of targeted molecular probes, that highlight specific molecules or cells, pathological processes can be visualized at a molecular level with high spatial resolution. In this review article, the development of pathophysiological changes leading to the development of the arterial wall are introduced and discussed. Additionally, principles of contrast enhanced imaging with non-specific contrast agents and molecular probes will be discussed and latest developments in the field of molecular imaging of the vascular wall will be introduced.

  14. Microgravity cultivation of cells and tissues

    Science.gov (United States)

    Freed, L. E.; Pellis, N.; Searby, N.; de Luis, J.; Preda, C.; Bordonaro, J.; Vunjak-Novakovic, G.

    1999-01-01

    In vitro studies of cells and tissues in microgravity, either simulated by cultivation conditions on earth or actual, during spaceflight, are expected to help identify mechanisms underlying gravity sensing and transduction in biological organisms. In this paper, we review rotating bioreactor studies of engineered skeletal and cardiovascular tissues carried out in unit gravity, a four month long cartilage tissue engineering study carried out aboard the Mir Space Station, and the ongoing laboratory development and testing of a system for cell and tissue cultivation aboard the International Space Station.

  15. 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.

  16. [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.

  17. Cardiovascular magnetic resonance in adults with previous cardiovascular surgery.

    Science.gov (United States)

    von Knobelsdorff-Brenkenhoff, Florian; Trauzeddel, Ralf Felix; Schulz-Menger, Jeanette

    2014-03-01

    Cardiovascular magnetic resonance (CMR) is a versatile non-invasive imaging modality that serves a broad spectrum of indications in clinical cardiology and has proven evidence. Most of the numerous applications are appropriate in patients with previous cardiovascular surgery in the same manner as in non-surgical subjects. However, some specifics have to be considered. This review article is intended to provide information about the application of CMR in adults with previous cardiovascular surgery. In particular, the two main scenarios, i.e. following coronary artery bypass surgery and following heart valve surgery, are highlighted. Furthermore, several pictorial descriptions of other potential indications for CMR after cardiovascular surgery are given.

  18. Cardiovascular system aging

    OpenAIRE

    Ocampo, José M; Gutiérrez, Javier

    2005-01-01

    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, inot...

  19. 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...

  20. Carbon dioxide balneotherapy and cardiovascular disease

    Science.gov (United States)

    Pagourelias, Efstathios D.; Zorou, Paraskevi G.; Tsaligopoulos, Miltiadis; Athyros, Vasilis G.; Karagiannis, Asterios; Efthimiadis, Georgios K.

    2011-09-01

    Carbon dioxide (CO2) balneotherapy is a kind of remedy with a wide spectrum of applications which have been used since the Middle Ages. However, its potential use as an adjuvant therapeutic option in patients with cardiovascular disease is not yet fully clarified. We performed a thorough review of MEDLINE Database, EMBASE, ISI WEB of Knowledge, COCHRANE database and sites funded by balneotherapy centers across Europe in order to recognize relevant studies and aggregate evidence supporting the use of CO2 baths in various cardiovascular diseases. The three main effects of CO2 hydrotherapy during whole body or partial immersion, including decline in core temperature, an increase in cutaneous blood flow, and an elevation of the score on thermal sensation, are analyzed on a pathophysiology basis. Additionally, the indications and contra-indications of the method are presented in an evidence-based way, while the need for new methodologically sufficient studies examining the use of CO2 baths in other cardiovascular substrates is discussed.

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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

  8. Cardiovascular Complications of Pregnancy

    Directory of Open Access Journals (Sweden)

    Maria Carolina Gongora

    2015-10-01

    Full Text Available 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.

  9. Cardiovascular diseases and periodontology.

    Science.gov (United States)

    Seymour, R A; Preshaw, P M; Thomason, J M; Ellis, J S; Steele, J G

    2003-04-01

    Cardiovascular diseases represent a widespread heterogeneous group of conditions that have significant morbidity and mortality. The various diseases and their treatments can have an impact upon the periodontium and the delivery of periodontal care. In this paper we consider three main topics and explore their relationship to the periodontist and the provision of periodontal treatment. The areas reviewed include the effect of cardiovascular drugs on the periodontium and management of patients with periodontal diseases; the risk of infective endocarditis arising from periodontal procedures; the inter-relationship between periodontal disease and coronary artery disease. Calcium-channel blockers and beta-adrenoceptor blockers cause gingival overgrowth and tooth demineralisation, respectively. Evidence suggests that stopping anticoagulant therapy prior to periodontal procedures is putting patients at a greater risk of thromboembolic disorders compared to the risk of prolonged bleeding. The relationship between dentistry and infective endocarditis remains a controversial issue. It would appear that spontaneous bacteraemia arising from a patient's oral hygiene practices is more likely to be the cause of endocarditis than one-off periodontal procedures. The efficacy of antibiotic prophylaxis is uncertain (and unlikely to be proven), and the risk of death from penicillin appears to be greater than the risk of death arising from infective endocarditis. Finally, the association between periodontal disease and coronary artery disease has been explored and there seem to be many issues with respect to data handling interpretation. Many putative mechanisms have been suggested; however, these only further highlight the need for intervention studies.

  10. 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.

  11. 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...

  12. Computational fluid dynamics modelling in cardiovascular medicine.

    Science.gov (United States)

    Morris, Paul D; Narracott, Andrew; von Tengg-Kobligk, Hendrik; Silva Soto, Daniel Alejandro; Hsiao, Sarah; Lungu, Angela; Evans, Paul; Bressloff, Neil W; Lawford, Patricia V; Hose, D Rodney; Gunn, Julian P

    2016-01-01

    This paper reviews the methods, benefits and challenges associated with the adoption and translation of computational fluid dynamics (CFD) modelling within cardiovascular medicine. CFD, a specialist area of mathematics and a branch of fluid mechanics, is used routinely in a diverse range of safety-critical engineering systems, which increasingly is being applied to the cardiovascular system. By facilitating rapid, economical, low-risk prototyping, CFD modelling has already revolutionised research and development of devices such as stents, valve prostheses, and ventricular assist devices. Combined with cardiovascular imaging, CFD simulation enables detailed characterisation of complex physiological pressure and flow fields and the computation of metrics which cannot be directly measured, for example, wall shear stress. CFD models are now being translated into clinical tools for physicians to use across the spectrum of coronary, valvular, congenital, myocardial and peripheral vascular diseases. CFD modelling is apposite for minimally-invasive patient assessment. Patient-specific (incorporating data unique to the individual) and multi-scale (combining models of different length- and time-scales) modelling enables individualised risk prediction and virtual treatment planning. This represents a significant departure from traditional dependence upon registry-based, population-averaged data. Model integration is progressively moving towards 'digital patient' or 'virtual physiological human' representations. When combined with population-scale numerical models, these models have the potential to reduce the cost, time and risk associated with clinical trials. The adoption of CFD modelling signals a new era in cardiovascular medicine. While potentially highly beneficial, a number of academic and commercial groups are addressing the associated methodological, regulatory, education- and service-related challenges. Published by the BMJ Publishing Group Limited. For permission

  13. Wall shear stress fixed points in cardiovascular fluid mechanics.

    Science.gov (United States)

    Arzani, Amirhossein; Shadden, Shawn C

    2018-05-17

    Complex blood flow in large arteries creates rich wall shear stress (WSS) vectorial features. WSS acts as a link between blood flow dynamics and the biology of various cardiovascular diseases. WSS has been of great interest in a wide range of studies and has been the most popular measure to correlate blood flow to cardiovascular disease. Recent studies have emphasized different vectorial features of WSS. However, fixed points in the WSS vector field have not received much attention. A WSS fixed point is a point on the vessel wall where the WSS vector vanishes. In this article, WSS fixed points are classified and the aspects by which they could influence cardiovascular disease are reviewed. First, the connection between WSS fixed points and the flow topology away from the vessel wall is discussed. Second, the potential role of time-averaged WSS fixed points in biochemical mass transport is demonstrated using the recent concept of Lagrangian WSS structures. Finally, simple measures are proposed to quantify the exposure of the endothelial cells to WSS fixed points. Examples from various arterial flow applications are demonstrated. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. 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...

  15. 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...

  16. Mortality of mothers from cardiovascular and non-cardiovascular causes following pregnancy complications in first delivery

    DEFF Research Database (Denmark)

    Lykke, Jacob Alexander; Langhoff-Roos, Jens; Lockwood, Charles J

    2010-01-01

    cardiovascular and non-cardiovascular causes following preterm delivery, small-for-gestational-age offspring and hypertensive disorders of pregnancy. We found that preterm delivery and small-for-gestational-age were both associated with subsequent death of mothers from cardiovascular and non...... cardiovascular and non-cardiovascular causes, while hypertensive disorders of pregnancy are markers of early death of mothers from cardiovascular causes....

  17. Wireless Monitoring for Patients with Cardiovascular Diseases and Parkinson's Disease.

    Science.gov (United States)

    Kefaliakos, Antonios; Pliakos, Ioannis; Charalampidou, Martha; Diomidous, Marianna

    2016-01-01

    The use of applications for mobile devices and wireless sensors is common for the sector of telemedicine. Recently various studies and systems were developed in order to help patients suffering from severe diseases such as cardiovascular diseases and Parkinson's disease. They present a challenge for the sector because such systems demand the flow of accurate data in real time and the use of specialized sensors. In this review will be presented some very interesting applications developed for patients with cardiovascular diseases and Parkinson's disease.

  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...... 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...... factors shared by siblings explained the associations between education and the cardiovascular disease outcomes but to varying degrees. This should be taken into account when planning interventions aimed at reducing educational inequalities in the development of cardiovascular disease, ischaemic heart...

  19. Women's cardiovascular health in India.

    Science.gov (United States)

    Chow, Clara K; Patel, Anushka A

    2012-03-01

    Cardiovascular diseases (CVDs) are the leading cause of death among adult women in many parts of India and a major cause of morbidity. In some parts of the world, gender inequities have been observed in cardiovascular healthcare and cardiovascular outcomes. The authors discuss the data for potential disparities in cardiovascular healthcare for women in India. Data on cardiovascular healthcare provision and CVD outcomes among women in India are generally lacking. The little available data suggest that women in rural areas, younger women and girl children with CVD are less likely to receive appropriate management than men, with this disparity most apparent in those of lower socioeconomic status and education. However, there is a particular lack of information about the prevention and management of atherosclerotic heart disease in women from a range of communities that comprise the extremely diverse population of India.

  20. 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...... to contain high amounts of SFA. However, cheese also contributes with several nutrients in the diet such as essential amino acids and calcium. The aim of this thesis was to examine the effect of cheese intake on CVD risk through evidence from both observational, intervention and explorative studies....... By reviewing results from published observational studies it was concluded that cheese does not seem to increase CVD risk, despite of the high SFA content of most cheeses. A human cross-over intervention study was conducted with the purpose of investigating the effect of hard cheese intake on risk markers...

  1. 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?

  2. 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...

  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 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...

  5. Cardiovascular magnetic resonance physics for clinicians: part I.

    Science.gov (United States)

    Ridgway, John P

    2010-11-30

    There are many excellent specialised texts and articles that describe the physical principles of cardiovascular magnetic resonance (CMR) techniques. There are also many texts written with the clinician in mind that provide an understandable, more general introduction to the basic physical principles of magnetic resonance (MR) techniques and applications. There are however very few texts or articles that attempt to provide a basic MR physics introduction that is tailored for clinicians using CMR in their daily practice. This is the first of two reviews that are intended to cover the essential aspects of CMR physics in a way that is understandable and relevant to this group. It begins by explaining the basic physical principles of MR, including a description of the main components of an MR imaging system and the three types of magnetic field that they generate. The origin and method of production of the MR signal in biological systems are explained, focusing in particular on the two tissue magnetisation relaxation properties (T1 and T2) that give rise to signal differences from tissues, showing how they can be exploited to generate image contrast for tissue characterisation. The method most commonly used to localise and encode MR signal echoes to form a cross sectional image is described, introducing the concept of k-space and showing how the MR signal data stored within it relates to properties within the reconstructed image. Before describing the CMR acquisition methods in detail, the basic spin echo and gradient pulse sequences are introduced, identifying the key parameters that influence image contrast, including appearances in the presence of flowing blood, resolution and image acquisition time. The main derivatives of these two pulse sequences used for cardiac imaging are then described in more detail. Two of the key requirements for CMR are the need for data acquisition first to be to be synchronised with the subject's ECG and to be fast enough for the subject

  6. Using Polymeric Scaffolds for Vascular Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Alida Abruzzo

    2014-01-01

    Full Text Available With the high occurrence of cardiovascular disease and increasing numbers of patients requiring vascular access, there is a significant need for small-diameter (<6 mm inner diameter vascular graft that can provide long-term patency. Despite the technological improvements, restenosis and graft thrombosis continue to hamper the success of the implants. Vascular tissue engineering is a new field that has undergone enormous growth over the last decade and has proposed valid solutions for blood vessels repair. The goal of vascular tissue engineering is to produce neovessels and neoorgan tissue from autologous cells using a biodegradable polymer as a scaffold. The most important advantage of tissue-engineered implants is that these tissues can grow, remodel, rebuild, and respond to injury. This review describes the development of polymeric materials over the years and current tissue engineering strategies for the improvement of vascular conduits.

  7. Clinical Application of Induced Pluripotent Stem Cells in Cardiovascular Medicine.

    Science.gov (United States)

    Chi, Hong-jie; Gao, Song; Yang, Xin-chun; Cai, Jun; Zhao, Wen-shu; Sun, Hao; Geng, Yong-Jian

    2015-01-01

    Induced pluripotent stem cells (iPSCs) are generated by reprogramming human somatic cells through the overexpression of four transcription factors: Oct4, Sox2, Klf4 and c-Myc. iPSCs are capable of indefinite self-renewal, and they can differentiate into almost any type of cell in the body. These cells therefore offer a highly valuable therapeutic strategy for tissue repair and regeneration. Recent experimental and preclinical research has revealed their potential for cardiovascular disease diagnosis, drug screening and cellular replacement therapy. Nevertheless, significant challenges remain in terms of the development and clinical application of human iPSCs. Here, we review current progress in research related to patient-specific iPSCs for ex vivo modeling of cardiovascular disorders and drug screening, and explore the potential of human iPSCs for use in the field of cardiovascular regenerative medicine. © 2015 S. Karger AG, Basel.

  8. The Effects of Ocimum Gratissimum Leaf Extract on Cardiovascular ...

    African Journals Online (AJOL)

    At the end of the period the blood pressure, heart rate, packed cell volume ... Also determined were the urine output, urine flow rate and urinary excretion of ... No significant histological changes were observed in renal cortical tissue of O.

  9. 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

  10. 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 ...

  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. Cerebral blood flow changes in response to elevated intracranial pressure in rabbits and bluefish: a comparative study.

    Science.gov (United States)

    Beiner, J M; Olgivy, C S; DuBois, A B

    1997-03-01

    In mammals, the cerebrovascular response to increases in intracranial pressure may take the form of the Cushing response, which includes increased mean systemic arterial pressure, bradycardia and diminished respirations. The mechanism, effect and value of these responses are debated. Using laser-Doppler flowmetry to measure cerebral blood flow, we analyzed the cardiovascular responses to intracranial pressure raised by epidural infusion of mock cerebrospinal fluid in the bluefish and in the rabbit, and compare the results. A decline in cerebral blood flow preceding a rise in mean systemic arterial pressure was observed in both species. Unlike bluefish, rabbits exhibit a threshold of intracranial pressure below which cerebral blood flow was maintained and no cardiovascular changes were observed. The difference in response between the two species was due to the presence of an active autoregulatory system in the cerebral tissue of rabbits and its absence in bluefish. For both species studied, the stimulus for the Cushing response seems to be a decrement in cerebral blood flow. The resulting increase in the mean systemic arterial pressure restores cerebral blood flow to levels approaching controls.

  13. Cardiovascular MRI with ferumoxytol

    International Nuclear Information System (INIS)

    Finn, J.P.; Nguyen, K.-L.; Han, F.; Zhou, Z.; Salusky, I.; Ayad, I.; Hu, P.

    2016-01-01

    The practice of contrast-enhanced magnetic resonance angiography (CEMRA) has changed significantly in the span of a decade. Concerns regarding gadolinium (Gd)-associated nephrogenic systemic fibrosis in those with severely impaired renal function spurred developments in low-dose CEMRA and non-contrast MRA as well as efforts to seek alternative MR contrast agents. Originally developed for MR imaging use, ferumoxytol (an ultra-small superparamagnetic iron oxide nanoparticle), is currently approved by the US Food and Drug Administration for the treatment of iron deficiency anaemia in adults with renal disease. Since its clinical availability in 2009, there has been rising interest in the scientific and clinical use of ferumoxytol as an MR contrast agent. The unique physicochemical and pharmacokinetic properties of ferumoxytol, including its long intravascular half-life and high r 1 relaxivity, support a spectrum of MRI applications beyond the scope of Gd-based contrast agents. Moreover, whereas Gd is not found in biological systems, iron is essential for normal metabolism, and nutritional iron deficiency poses major public health challenges worldwide. Once the carbohydrate shell of ferumoxytol is degraded, the elemental iron at its core is incorporated into the reticuloendothelial system. These considerations position ferumoxytol as a potential game changer in the field of CEMRA and MRI. In this paper, we aim to summarise our experience with the cardiovascular applications of ferumoxytol and provide a brief synopsis of ongoing investigations on ferumoxytol-enhanced MR applications.

  14. Depression and cardiovascular disease.

    Science.gov (United States)

    Elderon, Larkin; Whooley, Mary A

    2013-01-01

    Approximately one out of every five patients with cardiovascular disease (CVD) suffers from major depressive disorder (MDD). Both MDD and depressive symptoms are risk factors for CVD incidence, severity and outcomes. Great progress has been made in understanding potential mediators between MDD and CVD, particularly focusing on health behaviors. Investigators have also made considerable strides in the diagnosis and treatment of depression among patients with CVD. At the same time, many research questions remain. In what settings is depression screening most effective for patients with CVD? What is the optimal screening frequency? Which therapies are safe and effective? How can we better integrate the care of mental health conditions with that of CVD? How do we motivate depressed patients to change health behaviors? What technological tools can we use to improve care for depression? Gaining a more thorough understanding of the links between MDD and heart disease, and how best to diagnose and treat depression among these patients, has the potential to substantially reduce morbidity and mortality from CVD. Published by Elsevier Inc.

  15. Cardiovascular and interventional radiology

    International Nuclear Information System (INIS)

    White, R.I. Jr.

    1985-01-01

    A symposium of eight short but complete papers giving an overview of interventional radiology is presented. Organized by Dr. William Casarella, this symposium is certainly the most current review of the subject available. This year's cardiovascular section is again heavily weighted toward interventional radiology. Abrams and Doubilet's article on the underutilization of angioplasty is important because it describes the cost effectiveness of this method. Most health planners, right or wrong, have complained about overutilization of diagnostic radiology procedures. In general, the opposite is true for interventional procedures - they are underutilized. If the authors draw the attention of their hospital administrators to these approaches and also produce the data on long-term follow-up for our medical colleagues, interventional radiology may realize its full potential. Articles on cardiac magnetic resonance imaging are beginning to appear and this technique seems to have great potential. An important article, which is the first prospective study comparing lung scintigraphy and pulmonary angiography in the diagnosis of pulmonary embolism, supports the increased use of pulmonary angiography. Finally, an article on complications of percutaneous biliary drainage provokes some discussion of its value for routine preoperative use

  16. 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.

  17. 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

  18. 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

  19. Cardiovascular autonomic neuropathy in diabetes

    DEFF Research Database (Denmark)

    Spallone, Vincenza; Ziegler, Dan; Freeman, Roy

    2011-01-01

    Cardiovascular Autonomic Neuropathy (CAN) Subcommittee of Toronto Consensus Panel on Diabetic Neuropathy worked to update CAN guidelines, with regard to epidemiology, clinical impact, diagnosis, usefulness of CAN testing, and management. CAN is the impairment of cardiovascular autonomic control...... in type 2 diabetes. CAN is a risk marker of mortality and cardiovascular morbidity, and possibly a progression promoter of diabetic nephropathy. Criteria for CAN diagnosis and staging are: 1. one abnormal cardio-vagal test identifies possible or early CAN; 2. at least two abnormal cardio-vagal tests....... diagnosis of CAN clinical forms, 2. detection and tailored treatment of CAN clinical correlates (e.g. tachycardia, OH, nondipping, QT interval prolongation), 3. risk stratification for diabetic complications and cardiovascular morbidity and mortality, and 4. modulation of targets of diabetes therapy...

  20. 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

  1. Cardiovascular risk in Turner syndrome.

    Science.gov (United States)

    Donato, Beatriz; Ferreira, Maria João

    2018-06-01

    Turner syndrome is a relatively common genetic disorder of female development, characterized by partial or complete absence of an X chromosome, with a variable clinical presentation. Congenital or acquired cardiovascular disease is highly prevalent and a major cause of early death in this syndrome. The most feared complication is aortic dissection, which can occur at a very young age and requires careful assessment of its risk factors. A systematic literature search identified sixty relevant publications. These were reviewed with regard to the increased risk of cardiovascular disease in women with Turner syndrome, especially in pregnancy. The most common congenital cardiovascular defects are presented and illustrated with appropriate iconography. The current recommendations regarding the screening and monitoring of cardiovascular disease in these patients are discussed. Copyright © 2018 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. Genetic risks for cardiovascular diseases

    NARCIS (Netherlands)

    Zafarmand, M.H.

    2008-01-01

    Atherosclerotic cardiovascular disease (CVD), which involves the heart, brain, and peripheral circulation, is a major health problem world-wide. The development of atherosclerosis is a complex process, and several established risk factors are involved. Nevertheless, these established risk factors

  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. Lycopene Deficiency in Ageing and Cardiovascular Disease

    Science.gov (United States)

    Petyaev, Ivan M.

    2016-01-01

    Lycopene is a hydrocarbon phytochemical belonging to the tetraterpene carotenoid family and is found in red fruit and vegetables. Eleven conjugated double bonds predetermine the antioxidant properties of lycopene and its ability to scavenge lipid peroxyl radicals, reactive oxygen species, and nitric oxide. Lycopene has a low bioavailability rate and appears in the blood circulation incorporated into chylomicrons and other apo-B containing lipoproteins. The recent body of evidence suggests that plasma concentration of lycopene is not only a function of intestinal absorption rate but also lycopene breakdown via enzymatic and oxidative pathways in blood and tissues. Oxidative stress and the accumulation of reactive oxygen species and nitric oxide may represent a major cause of lycopene depletion in ageing, cardiovascular disease, and type 2 diabetes mellitus. It has been shown recently that low carotenoid levels, and especially decreased serum lycopene levels, are strongly predictive of all-cause mortality and poor outcomes of cardiovascular disease. However, there is a poor statistical association between dietary and serum lycopene levels which occurs due to limited bioavailability of lycopene from dietary sources. Hence, it is very unlikely that nutritional intervention alone could be instrumental in the correction of lycopene and carotenoid deficiency. Therefore, new nutraceutical formulations of carotenoids with enhanced bioavailability are urgently needed. PMID:26881023

  5. 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.

  6. 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.

  7. Cardiovascular adaptations to exercise training

    DEFF Research Database (Denmark)

    Hellsten, Ylva; Nyberg, Michael

    2016-01-01

    Aerobic exercise training leads to cardiovascular changes that markedly increase aerobic power and lead to improved endurance performance. The functionally most important adaptation is the improvement in maximal cardiac output which is the result of an enlargement in cardiac dimension, improved...... and peripheral cardiovascular adaptations with a focus on humans, but also covers animal data. © 2016 American Physiological Society. Compr Physiol 6:1-32, 2016....

  8. Platelet-derived growth factor-C and -D in the cardiovascular system and diseases.

    Science.gov (United States)

    Lee, Chunsik; Li, Xuri

    2018-08-01

    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.

  9. Effects of kynurenic acid on cardiovascular system

    Directory of Open Access Journals (Sweden)

    Piotr Kozłowski

    2017-08-01

    Full Text Available Kynurenic Acid (KYNA is an endogenous metabolite of tryptophan (TRP which is produced by aminotransferase KAT I and KAT II in the central nervous system and peripheral tissues. Moreover it has been shown that it can be supplied with food. KYNA is an antagonist of glutamate receptors NMDA and antagonist of acetylcholine α7. As we know KYNA can not penetrate or penetrates in very small amounts through the blood-brain barier. Several studies have demonstrated that kynurenine metabolism plays an important role in many neurodegenerative diseases and psychiatric disorders (Parkinson's disease, Huntington's disease, Alzheimer's disease, amyotrophic lateral sclerosis, multiple sclerosis, depression, schizophrenia. Less is known about a peripheral KYNA. Studies suggest that KYNA may have antiatherosclerotic activity and many other beneficial effects on cardiovascular system.

  10. Environmental Factors and Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Omer Faruk Tekbas

    2008-10-01

    Full Text Available Epidemiological and clinical observations have led to the hypothesis that the risk of developing cardiovascular diseases is influenced not only by genetic, lifestyle and major risk factors, but also by environmental factors. Environmental factors are considered key determinants of cardiovascular diseases. Although lifestyle choices such as smoking, diet, and exercise are viewed as major environmental influences, the contribution of pollutants and environmental chemicals is less clear. Accumulating evidence suggests that exposure to physically and chemical pollutants could elevate the risk of cardiovascular diseases. Many epidemiological studies report that exposure to physically, biologically and socio-cultural environmental factors are associated with an increase in cardiovascular mortality. Relationships between environmental factors and coronary arter disease, arhythmias, and cardiomyopathies have been reported. Exposures to arsenic, lead, cadmium, pollutant gases, solvents, and pesticides have also been linked to increased incidence of cardiovascular disease. In this paper, I review that relationships between exposure to physically, chemical, biologically and socio-cultural environmental factors and cardiovascular diseases. [TAF Prev Med Bull 2008; 7(5.000: 435-444

  11. IgG4-related cardiovascular disease. The emerging role of cardiovascular imaging.

    Science.gov (United States)

    Mavrogeni, Sophie; Markousis-Mavrogenis, George; Kolovou, Genovefa

    2017-01-01

    Immunoglobulin 4-related disease (IgG4-related disease) is a systemic inflammatory disease that presents with increases of serum IgG4. It may affect various systems, including the cardiovascular (CV) system. Assessment of serum IgG4 levels and involved organ biopsy are necessary for diagnosis. IgG4-related disease is characterized by fibrosclerosis, lymphocytic infiltration and presence of IgG4-positive plasma cells. The disease usually responds to treatment with corticosteroids and/or immunosuppressive medication. CV involvement may manifest as cardiac pseudotumors, inflammatory periaortitis, coronary arteritis and/or pericarditis. IgG4-related cardiovascular disorders can severely affect patient prognosis. Various imaging techniques, including echocardiography, Computed Tomography (CT), 18FDG-PET, Cardiovascular Magnetic Resonance (CMR) and cardiac catheterisation, have been successfully used for early disease detection and follow-up. Echocardiography and vascular ultrasound are the most commonly used non-invasive, non-radiating imaging techniques for the evaluation of IgG4-related CV disease. Periaortitis/periarteritis can be also assessed by CT, showing a soft tissue thickening around arteries. Coronary artery aneurysms can be easily diagnosed by coronary CT. In case of active periarterial or coronary artery inflammation, 18FDG-PET will show FDG uptake at the area of the lesion. CMR, due to its capability to perform function and tissue characterisation, can offer an integrated imaging of aorta, coronary arteries and the heart, assessment of disease acuity, extent of fibrosis and guide further treatment. However, multimodality imaging may be necessary for assessment of disease activity and fibrosis extent in those cases with multifocal CV involvement. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. 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.

  13. Obesity and Cardiovascular Disease.

    Science.gov (United States)

    Ortega, Francisco B; Lavie, Carl J; Blair, Steven N

    2016-05-27

    The prevalence of obesity has increased worldwide over the past few decades. In 2013, the prevalence of obesity exceeded the 50% of the adult population in some countries from Oceania, North Africa, and Middle East. Lower but still alarmingly high prevalence was observed in North America (≈30%) and in Western Europe (≈20%). These figures are of serious concern because of the strong link between obesity and disease. In the present review, we summarize the current evidence on the relationship of obesity with cardiovascular disease (CVD), discussing how both the degree and the duration of obesity affect CVD. Although in the general population, obesity and, especially, severe obesity are consistently and strongly related with higher risk of CVD incidence and mortality, the one-size-fits-all approach should not be used with obesity. There are relevant factors largely affecting the CVD prognosis of obese individuals. In this context, we thoroughly discuss important concepts such as the fat-but-fit paradigm, the metabolically healthy but obese (MHO) phenotype and the obesity paradox in patients with CVD. About the MHO phenotype and its CVD prognosis, available data have provided mixed findings, what could be partially because of the adjustment or not for key confounders such as cardiorespiratory fitness, and to the lack of consensus on the MHO definition. In the present review, we propose a scientifically based harmonized definition of MHO, which will hopefully contribute to more comparable data in the future and a better understanding on the MHO subgroup and its CVD prognosis. © 2016 American Heart Association, Inc.

  14. Cardiovascular transition at birth: a physiological sequence.

    Science.gov (United States)

    Hooper, Stuart B; Te Pas, Arjan B; Lang, Justin; van Vonderen, Jeroen J; Roehr, Charles Christoph; Kluckow, Martin; Gill, Andrew W; Wallace, Euan M; Polglase, Graeme R

    2015-05-01

    The transition to newborn life at birth involves major cardiovascular changes that are triggered by lung aeration. These include a large increase in pulmonary blood flow (PBF), which is required for pulmonary gas exchange and to replace umbilical venous return as the source of preload for the left heart. Clamping the umbilical cord before PBF increases reduces venous return and preload for the left heart and thereby reduces cardiac output. Thus, if ventilation onset is delayed following cord clamping, the infant is at risk of superimposing an ischemic insult, due to low cardiac output, on top of an asphyxic insult. Much debate has centered on the timing of cord clamping at birth, focusing mainly on the potential for a time-dependent placental to infant blood transfusion. This has prompted recommendations for delayed cord clamping for a set time after birth in infants not requiring resuscitation. However, recent evidence indicates that ventilation onset before cord clamping mitigates the adverse cardiovascular consequences caused by immediate cord clamping. This indicates that the timing of cord clamping should be based on the infant's physiology rather than an arbitrary period of time and that delayed cord clamping may be of greatest benefit to apneic infants.

  15. 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

  16. Incremental value of PET and MRI in the evaluation of cardiovascular abnormalities.

    Science.gov (United States)

    Chalian, Hamid; O'Donnell, James K; Bolen, Michael; Rajiah, Prabhakar

    2016-08-01

    The cardiovascular system is affected by a wide range of pathological processes, including neoplastic, inflammatory, ischemic, and congenital aetiology. Magnetic resonance imaging (MRI) and positron emission tomography (PET) are state-of-the-art imaging modalities used in the evaluation of these cardiovascular disorders. MRI has good spatial and temporal resolutions, tissue characterization and multi-planar imaging/reconstruction capabilities, which makes it useful in the evaluation of cardiac morphology, ventricular and valvar function, disease characterization, and evaluation of myocardial viability. FDG-PET provides valuable information on the metabolic activity of the cardiovascular diseases, including ischemia, inflammation, and neoplasm. MRI and FDG-PET can provide complementary information on the evaluation of several cardiovascular disorders. For example, in cardiac masses, FDG-PET provides the metabolic information for indeterminate cardiac masses. MRI can be used for localizing and characterizing abnormal hypermetabolic foci identified incidentally on PET scan and also for local staging. A recent advance in imaging technology has been the development of integrated PET/MRI systems that utilize the advantages of PET and MRI in a single examination. The goal of this manuscript is to provide a comprehensive review on the incremental value of PET and MRI in the evaluation of cardiovascular diseases. • MRI has good spatial and temporal resolutions, tissue characterization, and multi-planar reconstruction • FDG-PET provides valuable information on the metabolic activity of cardiovascular disorders • PET and MRI provide complementary information on the evaluation of cardiovascular disorders.

  17. Simulation of Cardiovascular Response to the Head-Up/Head-Down Tilt at Different Angles

    Science.gov (United States)

    Liu, Yang; Lu, Hong-Bing; Jiao, Chun; Zhang, Li-Fan

    2008-06-01

    The disappearance of hydrostatic pressure is the original factor that causes the changes of cardiovascular system under microgravity. The hydrostatical changes can be simulated by postural changes. Especially the head-down position can be used to simulate the effects of microgravity. The goal of this investigation was to develop a mathematical model for simulation of the human cardiovascular responses to acute and prolonged exposure under microgravity environment. We were particularly interested in the redistribution of transmural pressures, flows, blood volume, and the consequent alterations in local hemodynamics in different cardiovascular compartments during acute exposure and chronic adjustments. As a preliminary study, we first developed a multi-element, distributed hemodynamic model of human cardiovascular system, and verified the model to simulate cardiovascular changes during head up/down tilt at various angles.

  18. The Impact of Biomechanics in Tissue Engineering and Regenerative Medicine

    Science.gov (United States)

    Butler, David L.; Goldstein, Steven A.; Guo, X. Edward; Kamm, Roger; Laurencin, Cato T.; McIntire, Larry V.; Mow, Van C.; Nerem, Robert M.; Sah, Robert L.; Soslowsky, Louis J.; Spilker, Robert L.; Tranquillo, Robert T.

    2009-01-01

    Biomechanical factors profoundly influence the processes of tissue growth, development, maintenance, degeneration, and repair. Regenerative strategies to restore damaged or diseased tissues in vivo and create living tissue replacements in vitro have recently begun to harness advances in understanding of how cells and tissues sense and adapt to their mechanical environment. It is clear that biomechanical considerations will be fundamental to the successful development of clinical therapies based on principles of tissue engineering and regenerative medicine for a broad range of musculoskeletal, cardiovascular, craniofacial, skin, urinary, and neural tissues. Biomechanical stimuli may in fact hold the key to producing regenerated tissues with high strength and endurance. However, many challenges remain, particularly for tissues that function within complex and demanding mechanical environments in vivo. This paper reviews the present role and potential impact of experimental and computational biomechanics in engineering functional tissues using several illustrative examples of past successes and future grand challenges. PMID:19583462

  19. 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

  20. Gender bias in cardiovascular advertisements.

    Science.gov (United States)

    Ahmed, Sofia B; Grace, Sherry L; Stelfox, Henry Thomas; Tomlinson, George; Cheung, Angela M

    2004-11-01

    Women with cardiovascular disease are treated less aggressively than men. The reasons for this disparity are unclear. Pharmaceutical advertisements may influence physician practices and patient care. To determine if female and male patients are equally likely to be featured in cardiovascular advertisements. We examined all cardiovascular advertisements from US editions of general medical and cardiovascular journals published between 1 January 1996 and 30 June 1998. For each unique advertisement, we recorded the total number of journal appearances and the number of appearances in journals' premium positions. We noted the gender, age, race and role of both the primary figure and the majority of people featured in the advertisement. Nine hundred and nineteen unique cardiovascular advertisements were identified of which 254 depicted a patient as the primary figure. A total of 20%[95% confidence interval (CI) 15.3-25.5%] of these advertisements portrayed a female patient, while 80% (95% CI 74.5-84.7%) depicted a male patient, P advertisements appeared 249 times (13.3%; 95% CI 8.6-18.9%) while male patient advertisements appeared 1618 times (86.7%; 95% CI 81.1-91.4%), P advertisements also had significantly fewer mean appearances than male patient advertisements in journals' premium positions (0.82 vs. 1.99, P=0.02). Similar results were seen when the advertisements were analysed according to predominant gender. Despite increasing emphasis on cardiovascular disease in women, significant under-representation of female patients exists in cardiovascular advertisements. Physicians should be cognizant of this gender bias.

  1. 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

  2. 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.

  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. MRI of cardiovascular malformations

    International Nuclear Information System (INIS)

    Kastler, Bruno; Universite de Franche-Comte, Besancon; Centre Hospitalier Sherbrooke Univ., PQ

    2011-01-01

    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.)

  5. 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

  6. Cardiovascular Safety Pharmacology of Sibutramine.

    Science.gov (United States)

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

    2015-07-01

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

  7. The cardiovascular system after exercise

    Science.gov (United States)

    Romero, Steven A.; Minson, Christopher T.

    2017-01-01

    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. PMID:28153943

  8. 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.

  9. CELLULAR CONTROL OF CONNECTIVE TISSUE MATRIX TENSION†

    Science.gov (United States)

    Langevin, Helene M.; Nedergaard, Maiken; Howe, Alan

    2013-01-01

    The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occurs during viscoelastic relaxation. We propose that this response of fibroblasts plays a role in regulating extracellular fluid flow into the tissue, and protects against swelling when the matrix is stretched. This article reviews the evidence supporting possible mechanisms underlying this response including autocrine purinergic signaling. We also discuss fibroblast regulation of connective tissue tension with respect to lymphatic flow, immune function and cancer. PMID:23444198

  10. Cellular control of connective tissue matrix tension.

    Science.gov (United States)

    Langevin, Helene M; Nedergaard, Maiken; Howe, Alan K

    2013-08-01

    The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occurs during viscoelastic relaxation. We propose that this response of fibroblasts plays a role in regulating extracellular fluid flow into the tissue, and protects against swelling when the matrix is stretched. This article reviews the evidence supporting possible mechanisms underlying this response including autocrine purinergic signaling. We also discuss fibroblast regulation of connective tissue tension with respect to lymphatic flow, immune function, and cancer. Copyright © 2013 Wiley Periodicals, Inc.

  11. Cardiovascular function in pulmonary emphysema.

    Science.gov (United States)

    Visca, Dina; Aiello, Marina; Chetta, Alfredo

    2013-01-01

    Chronic obstructive pulmonary disease (COPD) and chronic cardiovascular disease, such as coronary artery disease, congestive heart failure, and cardiac arrhythmias, have a strong influence on each other, and systemic inflammation has been considered as the main linkage between them. On the other hand, airflow limitation may markedly affect lung mechanics in terms of static and dynamic hyperinflation, especially in pulmonary emphysema, and they can in turn influence cardiac performance as well. Skeletal mass depletion, which is a common feature in COPD especially in pulmonary emphysema patients, may have also a role in cardiovascular function of these patients, irrespective of lung damage. We reviewed the emerging evidence that highlights the role of lung mechanics and muscle mass impairment on ventricular volumes, stroke volume, and stroke work at rest and on exercise in the presence of pulmonary emphysema. Patients with emphysema may differ among COPD population even in terms of cardiovascular function.

  12. 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...

  13. 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...

  14. Phenylalanine kinetics in human adipose tissue.

    OpenAIRE

    Coppack, S W; Persson, M; Miles, J M

    1996-01-01

    Very little is known about the regulation of protein metabolism in adipose tissue. In this study systemic, adipose tissue, and forearm phenylalanine kinetics were determined in healthy postabsorptive volunteers before and during a 2-h glucose infusion (7 mg.kg-1.min-1). [3H]Phenylalanine was infused and blood was sampled from a radial artery, a subcutaneous abdominal vein, and a deep forearm vein. Adipose tissue and forearm blood flow were measured with 133Xe and plethysmography, respectively...

  15. 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.

  16. 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.

  17. 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...

  18. 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....

  19. 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...

  20. Cardiovascular risk factors in men

    DEFF Research Database (Denmark)

    Gyllenborg, J; Rasmussen, S L; Borch-Johnsen, Knut

    2001-01-01

    Males have higher risk of cardiovascular disease (CVD) than premenopausal females. Gonadal steroids are probably involved in the gender difference in CVD, but previous results have been conflicting. We investigated the associations between CVD risk factors and sex hormones in a cross-sectional de......Males have higher risk of cardiovascular disease (CVD) than premenopausal females. Gonadal steroids are probably involved in the gender difference in CVD, but previous results have been conflicting. We investigated the associations between CVD risk factors and sex hormones in a cross...

  1. Photocurable surgical tissue adhesive glues composed of photoreactive gelatin and poly(ethylene glycol) diacrylate.

    Science.gov (United States)

    Nakayama, Y; Matsuda, T

    1999-01-01

    This article presents a novel photochemically driven surgical tissue adhesive technology using photoreactive gelatins and a water-soluble difunctional macromer (poly(ethylene glycol) diacrylate: PEGDA).The gelatins were partially derivatized with photoreactive groups, such as ultraviolet light (UV)-reactive benzophenone and visible light-reactive xanthene dye (e.g., fluorescein sodium salt, eosin Y, and rose bengal). A series of the prepared photocurable tissue adhesive glues, consisting of the photoreactive gelatin, PEGDA, and a saline solution with or without ascorbic acid as a reducing agent, were viscous solutions under warming, and their effectiveness was evaluated as hemostasis- and anastomosis-aid in cardiovascular surgery. Regardless of the type of photoreactive groups, the irradiation of the photocurable tissue adhesive glues by UV or visible light within 1 min produced water-swollen gels, which had a high adhesive strength to wet collagen film. These were due to the synergistic action of photoreactive group-initiated photo-cross-linking and photograft polymerization. An increase in the irradiation time resulted in increased gel yield and reduced water swellability. A decrease in the molecular weight of PEGDA and an increase in concentration of both gelatin and PEGDA resulted in reduced water swellability and increased tensile and burst strengths of the resultant gels. In rats whose livers were injured with a trephine in laparotomy, the bleeding spots were coated with the photocurable adhesive glue and irradiated through an optical fiber. The coated solution was immediately converted to a swollen gel. The gel was tightly adhered to the liver tissue presumably by interpenetration, and concomitantly hemostasis was completed. The anastomosis treatment with the photocurable glue in the canine abdominal or thoracic aortas incised with a knife resulted in little bleeding under pulsatile flow after declamping. Histological examination showed that the glues

  2. 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.

  3. Soluble elastin peptides in cardiovascular homeostasis: Foe or ally.

    Science.gov (United States)

    Qin, Zhenyu

    2015-05-01

    Elastin peptides, also known as elastin-derived peptides or elastokines, are soluble polypeptides in blood and tissue. The blood levels of elastin peptides are usually low but can increase during cardiovascular diseases, such as atherosclerosis, aortic aneurysm and diabetes with vascular complications. Generally, elastin peptides are derived from the degradation of insoluble elastic polymers. The biological activities of elastin peptides are bidirectional, e.g., a pro-inflammatory effect on monocyte migration induction vs. a protective effect on vasodilation promotion. However, recent in vivo studies have demonstrated that elastin peptides promote the formation of atherosclerotic plaques in hypercholesterolemic mice and induce hyperglycemia and elevations in plasma lipid levels in fasted mice. More important, the detrimental effects induced by elastin peptides can be largely inhibited by genetic or pharmacological blockade of the elastin receptor complex or by neutralization of an antibody against elastin peptides. These studies indicate new therapeutic strategies for the treatment of cardiovascular diseases by targeting elastin peptide metabolism. Therefore, the goal of this review is to summarize current knowledge about elastin peptides relevant to cardiovascular pathologies to further delineate their potential application in cardiovascular disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. 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.

  5. 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.

  6. Emerging issues in radiogenic cataracts and cardiovascular disease

    International Nuclear Information System (INIS)

    Hamada, Nobuyuki; Fujimichi, Yuki; Iwasaki, Toshiyasu; Nomura, Takaharu; Fujii, Noriko; Furuhashi, Masato; Kubo, Eri; Minamino, Tohru; Sato, Hitoshi

    2014-01-01

    In 2011, the International Commission on Radiological Protection issued a statement on tissue reactions (formerly termed non-stochastic or deterministic effects) to recommend lowering the threshold for cataracts and the occupational equivalent dose limit for the crystalline lens of the eye. Furthermore, this statement was the first to list circulatory disease (cardiovascular and cerebrovascular disease) as a health hazard of radiation exposure and to assign its threshold for the heart and brain. These changes have stimulated various discussions and may have impacts on some radiation workers, such as those in the medical sector. This paper considers emerging issues associated with cataracts and cardiovascular disease. For cataracts, topics dealt with herein include (1) the progressive nature, stochastic nature, target cells and trigger events of lens opacification, (2) roles of lens protein denaturation, oxidative stress, calcium ions, tumor suppressors and DNA repair factors in cataractogenesis, (3) dose rate effect, radiation weighting factor, and classification systems for cataracts, and (4) estimation of the lens dose in clinical settings. Topics for cardiovascular disease include experimental animal models, relevant surrogate markers, latency period, target tissues, and roles of inflammation and cellular senescence. Future research needs are also discussed. (author)

  7. 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

  8. 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

  9. Modeling of Cardiovascular Response to Weightlessness

    Science.gov (United States)

    Sharp, M. Keith

    1999-01-01

    It was the hypothesis of this Project that the Simple lack of hydrostatic pressure in microgravity generates several purely physical reactions that underlie and may explain, in part, the cardiovascular response to weightlessness. For instance, hydrostatic pressure within the ventricles of the heart may improve cardiac performance by promoting expansion of ventricular volume during diastole. The lack of hydrostatic pressure in microgravity might, therefore, reduce diastolic filling and cardiac performance. The change in transmural pressure is possible due to the difference in hydrostatic pressure gradients between the blood inside the ventricle and the lung tissue surrounding the ventricle due to their different densities. On the other hand, hydrostatic pressure within the vasculature may reduce cardiac inlet pressures because of the typical location of the heart above the hydrostatic indifference level (the level at which pressure remains constant throughout changes in gravity). Additional physical responses of the body to changing gravitational conditions may influence cardiovascular performance. For instance, fluid shifts from the lower body to the thorax in microgravity may serve to increase central venous pressure (CVP) and boost cardiac output (CO). The concurrent release of gravitational force on the rib cage may tend to increase chest girth and decrease pedcardial pressure, augmenting ventricular filling. The lack of gravity on pulmonary tissue may allow an upward shifting of lung mass, causing a further decrease in pericardial pressure and increased CO. Additional effects include diuresis early in the flight, interstitial fluid shifts, gradual spinal extension and movement of abdominal mass, and redistribution of circulatory impedance because of venous distention in the upper body and the collapse of veins in the lower body. In this project, the cardiovascular responses to changes in intraventricular hydrostatic pressure, in intravascular hydrostatic

  10. Vitamin E and cardiovascular disease

    NARCIS (Netherlands)

    Kleijnen, J.; Knipschild, P.; ter Riet, G.

    1989-01-01

    Randomized clinical trials of the effects of Vitamin E on complaints of intermittent claudication and angina pectoris are reviewed, and their methodological shortcomings are considered. Mechanisms by which Vitamin E might act in cardiovascular disease are discussed. The evidence about the possible

  11. The Relationship Between Microalbuminuria, Cardiovascular ...

    African Journals Online (AJOL)

    Background :In patients with type 2 diabetes, microalbuminuria is an early clinical sign suggestive of vascular damage to the glomerulus. Microalbuminuria has also been currently reported as an important risk factor for cardiovascular disease and becomes relevant in the management of type 2 diabetes. Objectives :This ...

  12. Animal Models of Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Carlos Zaragoza

    2011-01-01

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

  13. Animal models of cardiovascular diseases.

    Science.gov (United States)

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

    2011-01-01

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

  14. NKT cells in cardiovascular diseases

    NARCIS (Netherlands)

    Puijvelde, van G.H.M.; Kuiper, J.

    2017-01-01

    Despite life-style advice and the prescription of cholesterol-lowering and anti-thrombotic drugs, cardiovascular diseases are still the leading cause of death worldwide. Therefore, there is an urgent need for new therapeutic strategies focussing on atherosclerosis, the major underlying pathology of

  15. NKT cells in cardiovascular diseases.

    Science.gov (United States)

    van Puijvelde, Gijs H M; Kuiper, Johan

    2017-12-05

    Despite life-style advice and the prescription of cholesterol-lowering and anti-thrombotic drugs, cardiovascular diseases are still the leading cause of death worldwide. Therefore, there is an urgent need for new therapeutic strategies focussing on atherosclerosis, the major underlying pathology of cardiovascular diseases characterized by an accumulation of lipids in an inflamed arterial/vessel wall. CD1d-restricted lipid-sensing natural killer T (NKT) cells, bridging the innate and adaptive immunity, and CD1d-expressing antigen-presenting cells are detected in atherosclerotic lesions of mice and humans. In this review we will summarize studies that point to a critical role for NKT cells in the pathogenesis of atherosclerosis and other cardiovascular diseases by the secretion of pro-atherogenic cytokines and cytotoxins. These pro-atherogenic NKT cells are potential targets for new therapeutic strategies in the prevention and treatment of cardiovascular diseases. Additionally, proteins transferring lipids during atherosclerosis, which are also important in the loading of lipids onto CD1d and possible endogenous ligands responsible for the activation of NKT cells during atherosclerosis will be discussed. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Digital imaging in cardiovascular radiology

    International Nuclear Information System (INIS)

    Heintzen, P.H.; Brennecke, R.

    1983-01-01

    The present book contains 27 papers presented at an international symposium on digital imaging in cardiovascular radiology held in Kiel in 1982. The main themes were as follows. Introductory reviews, digital systems for X-ray video imaging, quantitative X-ray image analysis, and clinical applications. (MG)

  17. Seasonality of cardiovascular risk factors

    DEFF Research Database (Denmark)

    Marti-Soler, Helena; Gubelmann, Cédric; Aeschbacher, Stefanie

    2014-01-01

    OBJECTIVE: To assess the seasonality of cardiovascular risk factors (CVRF) in a large set of population-based studies. METHODS: Cross-sectional data from 24 population-based studies from 15 countries, with a total sample size of 237 979 subjects. CVRFs included Body Mass Index (BMI) and waist...

  18. Cardiovascular calcification. An inflammatory disease

    International Nuclear Information System (INIS)

    New, S.E.P.; Aikawa, E.

    2011-01-01

    Cardiovascular calcification is an independent risk factor for cardiovascular morbidity and mortality. This disease of dysregulated metabolism is no longer viewed as a passive degenerative disease, but instead as an active process triggered by pro-inflammatory cues. Furthermore, a positive feedback loop of calcification and inflammation is hypothesized to drive disease progression in arterial calcification. Both calcific aortic valve disease and atherosclerotic arterial calcification may possess similar underlying mechanisms. Early histopathological studies first highlighted the contribution of inflammation to cardiovascular calcification by demonstrating the accumulation of macrophages and T lymphocytes in 'early' lesions within the aortic valves and arteries. A series of in vitro work followed, which gave a mechanistic insight into the stimulation of smooth muscle cells to undergo osteogenic differentiation and mineralization. The emergence of novel technology, in the form of animal models and more recently molecular imaging, has enabled accelerated progression of this field, by providing strong evidence regarding the concept of this disorder as an inflammatory disease. Although there are still gaps in our knowledge of the mechanisms behind this disorder, this review discusses the various studies that have helped form the concept of the inflammation-dependent cardiovascular calcification paradigm. (author)

  19. Down Syndrome: A Cardiovascular Perspective

    Science.gov (United States)

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

    2009-01-01

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

  20. Psychosocial perspectives in cardiovascular disease

    NARCIS (Netherlands)

    Pedersen, S.S.; von Kaenel, R.; Tully, P.J.; Denollet, J.

    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.

  1. Cardiovascular Risk in Primary Hyperaldosteronism

    NARCIS (Netherlands)

    Prejbisz, A.; Warchol-Celinska, E.; Lenders, J.W.M.; Januszewicz, A.

    2015-01-01

    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

  2. Lipid measures and cardiovascular disease prediction

    NARCIS (Netherlands)

    van Wijk, D.F.; Stroes, E.S.G.; Kastelein, J.J.P.

    2009-01-01

    Traditional lipid measures are the cornerstone of risk assessment and treatment goals in cardiovascular prevention. Whereas the association between total, LDL-, HDL-cholesterol and cardiovascular disease risk has been generally acknowledged, the rather poor capacity to distinguish between patients

  3. Top 10 Myths about Cardiovascular Disease

    Science.gov (United States)

    ... Thromboembolism Aortic Aneurysm More Top 10 Myths about Cardiovascular Disease Updated:Mar 16,2018 How much do ... Healthy This content was last reviewed July 2015. Cardiovascular Conditions • Conditions Home • Arrhythmia and Atrial Fibrillation • Cardiac ...

  4. Comparative cardiovascular safety of dementia medications

    DEFF Research Database (Denmark)

    Fosbøl, Emil L; Peterson, Eric D; Holm, Ellen

    2012-01-01

    To compare the cardiovascular safety of currently marketed dementia medications in new users in the United States and Denmark.......To compare the cardiovascular safety of currently marketed dementia medications in new users in the United States and Denmark....

  5. Machine learning based analysis of cardiovascular images

    NARCIS (Netherlands)

    Wolterink, JM

    2017-01-01

    Cardiovascular diseases (CVDs), including coronary artery disease (CAD) and congenital heart disease (CHD) are the global leading cause of death. Computed tomography (CT) and magnetic resonance imaging (MRI) allow non-invasive imaging of cardiovascular structures. This thesis presents machine

  6. Detection of cardiovascular anomalies: Hybrid systems approach

    KAUST Repository

    Ledezma, Fernando; Laleg-Kirati, Taous-Meriem

    2012-01-01

    In this paper, we propose a hybrid interpretation of the cardiovascular system. Based on a model proposed by Simaan et al. (2009), we study the problem of detecting cardiovascular anomalies that can be caused by variations in some physiological

  7. Residual generator for cardiovascular anomalies detection

    KAUST Repository

    Belkhatir, Zehor; Laleg-Kirati, Taous-Meriem; Tadjine, Mohamed

    2014-01-01

    This paper discusses the possibility of using observer-based approaches for cardiovascular anomalies detection and isolation. We consider a lumped parameter model of the cardiovascular system that can be written in a form of nonlinear state

  8. Sex steroids and cardiovascular disease

    Directory of Open Access Journals (Sweden)

    Bu Beng Yeap

    2014-04-01

    Full Text Available As men grow older, testosterone (T levels decline and the significance of this change is debated. The evidence supporting a causal role for lower circulating T, or its metabolites dihydrotestosterone (DHT and estradiol, in the genesis of atherosclerosis and cardiovascular disease (CVD in men is limited. Observational studies associate low baseline T levels with carotid atherosclerosis, aortic and peripheral vascular disease, and with the incidence of cardiovascular events and mortality. Studies using mass spectrometry suggest that when total T is assayed optimally, calculation of free T might not necessarily improve risk stratification. There is limited evidence to support an association of estradiol with CVD. Interventional studies of T therapy in men with coronary artery disease have shown beneficial effects on exercise-induced myocardial ischemia. However, placebo-controlled, randomized clinical trials (RCTs of T therapy in men with the prespecified outcomes of cardiovascular events or deaths are lacking. Meta-analyses of randomized controlled trials of T published up to 2010 found no increase in cardiovascular events, mortality, or prostate cancer with therapy. Recently, in a trial of older men with mobility limitations, men randomized to receive a substantial dose of T reported cardiovascular adverse effects. This phenomenon was not reported from a comparable trial where men received a more conservative dose of T, suggesting a prudent approach should be adopted when considering therapy in frail older men with existing CVD. Adequately powered RCTs of T in middle-aged and older men are needed to clarify whether or not hormonal intervention would reduce the incidence of CVD.

  9. [Thyroid hormones and cardiovascular system].

    Science.gov (United States)

    Límanová, Zdeňka; Jiskra, Jan

    Cardiovascular system is essentially affected by thyroid hormones by way of their genomic and non-genomic effects. Untreated overt thyroid dysfunction is associated with higher cardiovascular risk. Although it has been studied more than 3 decades, in subclinical thyroid dysfunction the negative effect on cardiovascular system is much more controversial. Large meta-analyses within last 10 years have shown that subclinical hyperthyroidism is associated with higher cardiovascular risk than subclinical hypothyroidism. Conversely, in patients of age > 85 years subclinical hypothyroidism was linked with lower mortality. Therefore, subclinical hyperthyroidism should be rather treated in the elderly while subclinical hypothyroidism in the younger patients and the older may be just followed. An important problem on the border of endocrinology and cardiology is amiodarone thyroid dysfunction. Effective and safe treatment is preconditioned by distinguishing of type 1 and type 2 amiodarone induced hyperthyroidism. The type 1 should be treated with methimazol, therapeutic response is prolonged, according to recent knowledge immediate discontinuation of amiodarone is not routinely recommended and patient should be usually prepared to total thyroidectomy, or rather rarely 131I radioiodine ablation may be used if there is appropriate accumulation. In the type 2 there is a promt therapeutic response on glucocorticoids (within 1-2 weeks) with permanent remission or development of hypothyroidism. If it is not used for life-threatening arrhytmias, amiodarone may be discontinuated earlier (after several weeks). Amiodarone induced hypothyroidism is treated with levothyroxine without amiodarone interruption.Key words: amiodarone induced thyroid dysfunction - atrial fibrillation - cardiovascular risk - heart failure - hyperthyroidism - hypothyroidism - thyroid stimulating hormone.

  10. Sex steroids and cardiovascular disease

    Science.gov (United States)

    Yeap, Bu Beng

    2014-01-01

    As men grow older, testosterone (T) levels decline and the significance of this change is debated. The evidence supporting a causal role for lower circulating T, or its metabolites dihydrotestosterone (DHT) and estradiol, in the genesis of atherosclerosis and cardiovascular disease (CVD) in men is limited. Observational studies associate low baseline T levels with carotid atherosclerosis, aortic and peripheral vascular disease, and with the incidence of cardiovascular events and mortality. Studies using mass spectrometry suggest that when total T is assayed optimally, calculation of free T might not necessarily improve risk stratification. There is limited evidence to support an association of estradiol with CVD. Interventional studies of T therapy in men with coronary artery disease have shown beneficial effects on exercise-induced myocardial ischemia. However, placebo-controlled, randomized clinical trials (RCTs) of T therapy in men with the prespecified outcomes of cardiovascular events or deaths are lacking. Meta-analyses of randomized controlled trials of T published up to 2010 found no increase in cardiovascular events, mortality, or prostate cancer with therapy. Recently, in a trial of older men with mobility limitations, men randomized to receive a substantial dose of T reported cardiovascular adverse effects. This phenomenon was not reported from a comparable trial where men received a more conservative dose of T, suggesting a prudent approach should be adopted when considering therapy in frail older men with existing CVD. Adequately powered RCTs of T in middle-aged and older men are needed to clarify whether or not hormonal intervention would reduce the incidence of CVD. PMID:24407188

  11. Sleep apnea and cardiovascular risk.

    Science.gov (United States)

    Floras, John S

    2014-01-01

    Sleep apnea is evident in approximately 10% of adults in the general population, but in certain cardiovascular diseases, and in particular those characterized by sodium and water retention, its prevalence can exceed 50%. Although sleep apnea is not as yet integrated into formal cardiovascular risk assessment algorithms, there is increasing awareness of its importance in the causation or promotion of hypertension, coronary artery disease, heart failure, atrial arrhythmias, and stroke, and thus, not surprisingly, as a predictor of premature cardiovascular death. Sleep apnea manifests as two principal phenotypes, both characterized by respiratory instability: obstructive (OSA), which arises when sleep-related withdrawal of respiratory drive to the upper airway dilator muscles is superimposed upon a narrow and highly compliant airway predisposed to collapse, and central (CSA), which occurs when the partial pressure of arterial carbon dioxide falls below the apnea threshold, resulting in withdrawal of central drive to respiratory muscles. The present objectives are to: (1) review the epidemiology and patho-physiology of OSA and CSA, with particular emphasis on the role of renal sodium retention in initiating and promoting these processes, and on population studies that reveal the long-term consequences of untreated OSA and CSA; (2) illustrate mechanical, autonomic, chemical, and inflammatory mechanisms by which OSA and CSA can increase cardiovascular risk and event rates by initiating or promoting hypertension, atherosclerosis, coronary artery disease, heart failure, arrhythmias, and stroke; (3) highlight insights from randomized trials in which treating sleep apnea was the specific target of therapy; (4) emphasize the present lack of evidence that treating sleep apnea reduces cardiovascular risk and the current clinical equipoise concerning treatment of asymptomatic patients with sleep apnea; and (5) consider clinical implications and future directions of clinical

  12. The Role of Cardiovascular Magnetic Resonance Imaging in Heart Failure.

    Science.gov (United States)

    Peterzan, Mark A; Rider, Oliver J; Anderson, Lisa J

    2016-11-01

    Cardiovascular imaging is key for the assessment of patients with heart failure. Today, cardiovascular magnetic resonance imaging plays an established role in the assessment of patients with suspected and confirmed heart failure syndromes, in particular identifying aetiology. Its role in informing prognosis and guiding decisions around therapy are evolving. Key strengths include its accuracy; reproducibility; unrestricted field of view; lack of radiation; multiple abilities to characterise myocardial tissue, thrombus and scar; as well as unparalleled assessment of left and right ventricular volumes. T2* has an established role in the assessment and follow-up of iron overload cardiomyopathy and a role for T1 in specific therapies for cardiac amyloid and Anderson-Fabry disease is emerging.

  13. Resting cardiovascular function improvements in adult men ...

    African Journals Online (AJOL)

    Impaired cardiovascular function increases the risk for fatal and non-fatal cardiovascular disease, renal disease and all-cause mortality. Research has demonstrated an inverse relationship between these cardiovascular impairments and exercise. However, previous research has mainly focused on aerobic training since ...

  14. 14 CFR 67.111 - Cardiovascular.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Cardiovascular. 67.111 Section 67.111 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION First-Class Airman Medical Certificate § 67.111 Cardiovascular. Cardiovascular...

  15. 14 CFR 67.311 - Cardiovascular.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Cardiovascular. 67.311 Section 67.311 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Third-Class Airman Medical Certificate § 67.311 Cardiovascular. Cardiovascular...

  16. 14 CFR 67.211 - Cardiovascular.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Cardiovascular. 67.211 Section 67.211 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Second-Class Airman Medical Certificate § 67.211 Cardiovascular. Cardiovascular...

  17. Cardiovascular Responses of Snakes to Gravitational Gradients

    Science.gov (United States)

    Hsieh, Shi-Tong T.; Lillywhite, H. B.; Ballard, R. E.; Hargens, A. R.; Holton, Emily M. (Technical Monitor)

    1998-01-01

    Snakes are useful vertebrates for studies of gravitational adaptation, owing to their elongate body and behavioral diversification. Scansorial species have evolved specializations for regulating hemodynamics during exposure to gravitational stress, whereas, such adaptations are less well developed in aquatic and non-climbing species. We examined responses of the amphibious snake,\\italicize (Nerodia rhombifera), to increments of Gz (head-to-tail) acceleration force on both a short- and long-arm centrifuge (1.5 vs. 3.7 m radius, from the hub to tail end of snake). We recorded heart rate, dorsal aortic pressure, and carotid arterial blood flow during stepwise 0.25 G increments of Gz force (referenced at the tail) in conscious animals. The Benz tolerance of a snake was determined as the Gz level at which carotid blood flow ceased and was found to be significantly greater at the short- than long-arm centrifuge radius (1.57 Gz vs. 2.0 Gz, respectively; P=0.016). A similar pattern of response was demonstrated in semi-arboreal rat snakes,\\italicize{Elaphe obsoleta}, which are generally more tolerant of Gz force (2.6 Gz at 1.5m radius) than are water snakes. The tolerance differences of the two species reflected cardiovascular responses, which differed quantitatively but not qualitatively: heart rates increased while arterial pressure and blood flow decreased in response to increasing levels of Gz. Thus, in both species of snakes, a reduced gradient of Gz force (associated with greater centrifuge radius) significantly decreases the Gz level that can be tolerated.

  18. A clinical perspective of obesity, metabolic syndrome and cardiovascular disease

    Directory of Open Access Journals (Sweden)

    Thang S Han

    2016-02-01

    Full Text Available The metabolic syndrome is a condition characterized by a special constellation of reversible major risk factors for cardiovascular disease and type 2 diabetes. The main, diagnostic, components are reduced HDL-cholesterol, raised triglycerides, blood pressure and fasting plasma glucose, all of which are related to weight gain, specifically intra-abdominal/ectopic fat accumulation and a large waist circumference. Using internationally adopted arbitrary cut-off values for waist circumference, having metabolic syndrome doubles the risk of cardiovascular disease, but offers an effective treatment approach through weight management. Metabolic syndrome now affects 30–40% of people by age 65, driven mainly by adult weight gain, and by a genetic or epigenetic predisposition to intra-abdominal/ectopic fat accumulation related to poor intra-uterine growth. Metabolic syndrome is also promoted by a lack of subcutaneous adipose tissue, low skeletal muscle mass and anti-retroviral drugs. Reducing weight by 5–10%, by diet and exercise, with or without, anti-obesity drugs, substantially lowers all metabolic syndrome components, and risk of type 2 diabetes and cardiovascular disease. Other cardiovascular disease risk factors such as smoking should be corrected as a priority. Anti-diabetic agents which improve insulin resistance and reduce blood pressure, lipids and weight should be preferred for diabetic patients with metabolic syndrome. Bariatric surgery offers an alternative treatment for those with BMI ≥ 40 or 35–40 kg/m 2 with other significant co-morbidity. The prevalence of the metabolic syndrome and cardiovascular disease is expected to rise along with the global obesity epidemic: greater emphasis should be given to effective early weight-management to reduce risk in pre-symptomatic individuals with large waists.

  19. Clinical Perspectives of Urocortin and Related Agents for the Treatment of Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Keiichi Ikeda

    2012-01-01

    Full Text Available The effects of corticotropin-releasing hormone, also known as corticotropin-releasing factor (CRF, on the cardiovascular system have been intensively researched since its discovery. Moreover, the actions of urocortin (Ucn I on the cardiovascular system have also been intensively scrutinized following the cloning and identification of its receptor, CRF receptor type 2 (CRFR2, in peripheral tissues including the heart. Given the cardioprotective actions of CRFR2 ligands, the clinical potential of not only Ucn I but also Ucn II and III, which were later identified as more specific ligands for CRFR2, has received considerable attention from researchers. In addition, recent work has indicated that CRF type 1 receptor may be also involved in cardioprotection against ischemic/reperfusion injury. Here we provide a historical overview of research on Ucn I and related agents, their effects on the cardiovascular system, and the clinical potential of the use of such agents to treat cardiovascular diseases.

  20. Reduced levels of potential circulating biomarkers of cardiovascular diseases in apparently healthy vegetarian men.

    Science.gov (United States)

    Navarro, Julio Acosta; de Gouveia, Luiza Antoniazzi; Rocha-Penha, Lilliam; Cinegaglia, Naiara; Belo, Vanessa; Castro, Michele Mazzaron de; Sandrim, Valeria Cristina

    2016-10-01

    Several evidences report that a vegetarian diet is protector against cardiovascular diseases. Few studies have demonstrated the circulating profile of cardiovascular biomarkers in vegetarians. Therefore, the aims of the current study were compared the plasma concentrations of myeloperoxidase (MPO), metalloproteinase (MMP)-9, MMP-2, tissue inhibitor of MMP (TIMP)-1 and TIMP-2 between healthy vegetarian (Veg) and healthy omnivorous (Omn). Using ELISA and multiplexed bead immunoassay, we measured in plasma from 43 Veg and 41 Omn the cardiovascular biomarkers concentrations cited above. We found significant lower concentrations of MPO, MMP-9, MMP-2 and MMP-9/TIMP-1 ratio in Veg compared to Omn (all Pvegetarian diet is associated with a healthier profile of cardiovascular biomarkers compared to omnivorous. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Lycopene and Its Antioxidant Role in the Prevention of Cardiovascular Diseases-A Critical Review.

    Science.gov (United States)

    Müller, Lars; Caris-Veyrat, Catherine; Lowe, Gordon; Böhm, Volker

    2016-08-17

    The present review is based mainly on papers published between 2000 and 2011 and gives information about the properties of the carotenoid lycopene in chemical and biological systems and its possible role in preventing cardiovascular diseases (CVD). The main aim of this report is to highlight its role as an antioxidant, also reported are bioactive properties that may influence the development of foam cells and protection against endothelial cell damage. The paper will also examine recent observations that lycopene may improve blood flow and reduce inflammatory responses. Lycopene possesses antioxidant properties in vitro, and some epidemiological studies have reported protective effects against the progression of CVD. The oxidation of human low density lipoproteins (LDL) is a fundamental mechanism in the initiation of atherosclerosis. A beneficial role of lycopene as antioxidant in the prevention of CVD is suggested but the data are still controversial. Lycopene is believed to be the most potent carotenoid antioxidant in vitro. Tissue culture experiments and animal studies support potential cardioprotective effects for lycopene and other carotenoids in the blood. Most studies showed beneficial effects of lycopene to individuals who are antioxidant-deficient like elderly patients, or humans exposed to higher levels of oxidative stress like smokers, diabetics, hemodialysis patients and acute myocardial infarction patients. By defining the right population and combining antioxidant potentials of lycopene with vitamins and other bioactive plant compounds, the beneficial role of lycopene in CVD can be clarified in future studies.

  2. NMR techniques in the study of cardiovascular structure and functions

    International Nuclear Information System (INIS)

    Osbakken, M.; Haselgrove, J.

    1987-01-01

    The chapter titles of this book are: Introduction to NMR Techniques;Theory of NMR Probe Design;Overview of Magnetic Resonance Imaging to Study the Cardiovascular System;Vascular Anatomy and Physiology Studied with NMR Techniques;Assessment of Myocardial Ischemia and Infarction by Nuclear Magnetic Resonance Imaging;The Use of MRI in Congenital Heart Disease;Cardiomyopathies and Myocarditis Studied with NMR Techniques;Determination of Myocardial Mechanical Function with Magnetic Resonance Imaging Techniques;Determination of Flow Using NMR Techniques;The Use of Contrast Agents in Cardiac MRI;Can Cardiovascular Disease Be Effectively Evaluated with NMR Spectroscopy? NMR Studies of ATP Synthesis Reactions in the Isolated Heart;Studies of Intermediary Metabolism in the Heart by 13C NMR Spectroscopy;23Na and 39K NMR Spectroscopic Studies of the Intact Beating Heart;and Evaluation of Skeletal Muscle Metabolism in Patients with Congestive Heart Failure Using Phosphorus Nuclear Magnetic Resonance

  3. Risk factors for chronic transplant dysfunction and cardiovascular disease are related to accumulation of advanced glycation end-products in renal transplant recipients

    NARCIS (Netherlands)

    Hartog, Jasper W. L.; de Vries, Aiko P. J.; Bakker, Stephan J. L.; Graaff, Reindert; van Son, Willem J.; van der Heide, Jaap J. Homan; Gans, Reinold O. B.; Wolffenbuttel, Bruce H. R.; de Jong, Paul E.; Smit, Andries J.

    Background. Accumulation of advanced glycation end-products (AGEs) has been implicated in the pathogenesis of chronic transplant dysfunction and cardiovascular disease in renal transplant recipients. We aimed to investigate which factors are associated with tissue AGE accumulation in renal

  4. Risk factors for chronic transplant dysfunction and cardiovascular disease are related to accumulation of advanced glycation end-products in renal transplant recipients

    NARCIS (Netherlands)

    Hartog, Jasper W. L.; de Vries, Aiko P. J.; Bakker, Stephan J. L.; Graaff, Reindert; van Son, Willem J.; Homan van der Heide, Jaap J.; Gans, Reinold O. B.; Wolffenbuttel, Bruce H. R.; de Jong, Paul E.; Smit, Andries J.

    2006-01-01

    Accumulation of advanced glycation end-products (AGEs) has been implicated in the pathogenesis of chronic transplant dysfunction and cardiovascular disease in renal transplant recipients. We aimed to investigate which factors are associated with tissue AGE accumulation in renal transplant

  5. IgG4-related cardiovascular disease. The emerging role of cardiovascular imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mavrogeni, Sophie, E-mail: soma13@otenet.gr; Markousis-Mavrogenis, George; Kolovou, Genovefa

    2017-01-15

    Highlights: • Assessment of serum IgG4 levels and involved organ biopsy are necessary for diagnosis of IgG4-related disease. • CV involvement may manifest as cardiac pseudotumors, inflammatory periaortitis, coronary arteritis and/or pericarditis. • Echocardiography and vascular ultrasound are the most commonly used non-invasive, non-radiating imaging techniques. • CT can assess periarteritis and coronary artery aneurysms, while 18FDG-PET shows FDG uptake at the area of the lesion. • CMR offers an integrated imaging of CV system, including assessment of disease acuity, extent of fibrosis and can guide further treatment. - Abstract: Immunoglobulin 4-related disease (IgG4-related disease) is a systemic inflammatory disease that presents with increases of serum IgG4. It may affect various systems, including the cardiovascular (CV) system. Assessment of serum IgG4 levels and involved organ biopsy are necessary for diagnosis. IgG4-related disease is characterized by fibrosclerosis, lymphocytic infiltration and presence of IgG4-positive plasma cells. The disease usually responds to treatment with corticosteroids and/or immunosuppressive medication. CV involvement may manifest as cardiac pseudotumors, inflammatory periaortitis, coronary arteritis and/or pericarditis. IgG4-related cardiovascular disorders can severely affect patient prognosis. Various imaging techniques, including echocardiography, Computed Tomography (CT), 18FDG-PET, Cardiovascular Magnetic Resonance (CMR) and cardiac catheterisation, have been successfully used for early disease detection and follow-up. Echocardiography and vascular ultrasound are the most commonly used non-invasive, non-radiating imaging techniques for the evaluation of IgG4-related CV disease. Periaortitis/periarteritis can be also assessed by CT, showing a soft tissue thickening around arteries. Coronary artery aneurysms can be easily diagnosed by coronary CT. In case of active periarterial or coronary artery inflammation, 18

  6. IgG4-related cardiovascular disease. The emerging role of cardiovascular imaging

    International Nuclear Information System (INIS)

    Mavrogeni, Sophie; Markousis-Mavrogenis, George; Kolovou, Genovefa

    2017-01-01

    Highlights: • Assessment of serum IgG4 levels and involved organ biopsy are necessary for diagnosis of IgG4-related disease. • CV involvement may manifest as cardiac pseudotumors, inflammatory periaortitis, coronary arteritis and/or pericarditis. • Echocardiography and vascular ultrasound are the most commonly used non-invasive, non-radiating imaging techniques. • CT can assess periarteritis and coronary artery aneurysms, while 18FDG-PET shows FDG uptake at the area of the lesion. • CMR offers an integrated imaging of CV system, including assessment of disease acuity, extent of fibrosis and can guide further treatment. - Abstract: Immunoglobulin 4-related disease (IgG4-related disease) is a systemic inflammatory disease that presents with increases of serum IgG4. It may affect various systems, including the cardiovascular (CV) system. Assessment of serum IgG4 levels and involved organ biopsy are necessary for diagnosis. IgG4-related disease is characterized by fibrosclerosis, lymphocytic infiltration and presence of IgG4-positive plasma cells. The disease usually responds to treatment with corticosteroids and/or immunosuppressive medication. CV involvement may manifest as cardiac pseudotumors, inflammatory periaortitis, coronary arteritis and/or pericarditis. IgG4-related cardiovascular disorders can severely affect patient prognosis. Various imaging techniques, including echocardiography, Computed Tomography (CT), 18FDG-PET, Cardiovascular Magnetic Resonance (CMR) and cardiac catheterisation, have been successfully used for early disease detection and follow-up. Echocardiography and vascular ultrasound are the most commonly used non-invasive, non-radiating imaging techniques for the evaluation of IgG4-related CV disease. Periaortitis/periarteritis can be also assessed by CT, showing a soft tissue thickening around arteries. Coronary artery aneurysms can be easily diagnosed by coronary CT. In case of active periarterial or coronary artery inflammation, 18

  7. Cardiovascular disease in patients with osteogenesis imperfecta - a nationwide, register-based cohort study

    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...

  8. The effects of short-chain fatty acids on the cardiovascular system

    NARCIS (Netherlands)

    Richards, L.B.; Li, M.; van Esch, B.C.A.M.; Garssen, J.; Folkerts, G.

    2016-01-01

    The development of cardiovascular diseases is often attributable to loss of endothelial functions of the vascular tissue or to decreased contractile function of the heart muscle. These disturbances are often caused by imbalances in lipid and glucose metabolism. For instance, these imbalances can

  9. Are women with polycystic ovary syndrome at increased cardiovascular disease risk later in life?

    Science.gov (United States)

    Gunning, M N; Fauser, B C J M

    2017-06-01

    To date, the world's leading cause of death amongst women is cardiovascular disease. Polycystic ovary syndrome (PCOS) is associated with an unfavorable cardiometabolic profile in early life. Apart from dyslipidemia, obesity and onset of type 2 diabetes mellitus, androgens are thought to influence cardiovascular health. The question rises whether women with PCOS are truly at risk for cardiovascular disease in later life. In this review paper, we aim to reflect on this assumed relation based on studies in different stages of life in women with PCOS. Cardiovascular risk factors (type 2 diabetes mellitus, obesity and metabolic syndrome), surrogate outcomes (flow-mediated dilation, carotid intima-media thickness and coronary artery calcium) and clinical long-term outcomes (cardiovascular disease and mortality) will be summarized. Data on cardiovascular disease and mortality in peri- and postmenopausal women with PCOS appear to be controversial. Whether androgens have a protective or unfavorable influence on the manifestation of cardiovascular disease remains uncertain. The need for large, prospective, well-phenotyped cohort studies of women with PCOS is high. Only then will we be able to answer this research question.

  10. Primary Prevention of Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Danny J. Eapen, MD

    2016-09-01

    Full Text Available Cardiovascular disease (CVD is the leading cause of death worldwide. This article focuses on current guidelines for the primary prevention of CVD and addresses management of key risk factors. Dietary modification, weight loss, exercise, and tobacco use cessation are specific areas where focused efforts can successfully reduce CVD risk on both an individual and a societal level. Specific areas requiring management include dyslipidemia, hypertension, physical activity, diabetes, aspirin use, and alcohol intake. These preventive efforts have major public health implications. As the global population continues to grow, health care expenditures will also rise, with the potential to eventually overwhelm the health care system. Therefore it is imperative to apply our collective efforts on CVD prevention to improve the cardiovascular health of individuals, communities, and nations.

  11. Molecular imaging by cardiovascular MR.

    Science.gov (United States)

    Cyrus, Tillmann; Lanza, Gregory M; Wickline, Samuel A

    2007-01-01

    Do molecularly-targeted contrast agents have what it takes to usher in a paradigm shift as to how we will image cardiovascular disease in the near future? Moreover, are non-invasive vulnerable plaque detection and preemptive treatments with these novel nanoparticulate agents within reach for clinical applications? In this article, we attempt to make a compelling case for how the advent of molecularly-targeted nanoparticle technology may change the way we detect atherosclerotic lesions, determine their clinical significance and even provide non-invasive treatments. Focusing on imaging with cardiovascular MR, an overview of the latest developments in this rapidly evolving field of so-called "intelligent" contrast agents that are able to interrogate the vascular wall and various complementary advanced imaging technologies are presented.

  12. Cardiovascular Prevention of Cognitive Decline

    Directory of Open Access Journals (Sweden)

    Jean-Jacques Monsuez

    2011-01-01

    Full Text Available Midlife cardiovascular risk factors, including diabetes, hypertension, dyslipemia, and an unhealthy lifestyle, have been linked to subsequent incidence, delay of onset, and progression rate of Alzheimer disease and vascular dementia. Conversely, optimal treatment of cardiovascular risk factors prevents and slows down age-related cognitive disorders. The impact of antihypertensive therapy on cognitive outcome in patients with hypertension was assessed in large trials which demonstrated a reduction in progression of MRI white matter hyperintensities, in cognitive decline and in incidence of dementia. Large-scale database correlated statin use and reduction in the incidence of dementia, mainly in patients with documented atherosclerosis, but clinical trials failed to reach similar conclusions. Whether a multitargeted intervention would substantially improve protection, quality of life, and reduce medical cost expenditures in patients with lower risk profile has not been ascertained. This would require appropriately designed trials targeting large populations and focusing on cognitive decline as a primary outcome endpoint.

  13. Hiperhomocisteinemia e o risco cardiovascular

    OpenAIRE

    Gannabathula Sree Vani

    2002-01-01

    Nível elevado de homocisteína (Hcy) no plasma é considerado fator de risco de doença cardiovascular. Consumo reduzido de vitaminas B6, B12 e ácido fólico tem sido relacionado com hiperhomocisteinemia. O objetivo desse estudo foi verificar o consumo de vitaminas B6, B12 e ácido fólico nas populações urbana e rural, bem como a correlação dos níveis plasmáticos dessas vitaminas com os níveis plasmáticos de Hcy. Também determinamos os níveis séricos de lipídeos e avaliamos o risco cardiovascular ...

  14. Prediabetes and Cardiovascular Parameters in Obese Children and Adolescents

    Science.gov (United States)

    Eklioğlu, Beray Selver; Atabek, Mehmet Emre; Akyürek, Nesibe; Alp, Hayrullah

    2016-01-01

    Objective: In this study, our aim was to determine cardiovascular risk and cardiac function in prediabetic obese children and adolescents. Methods: The study was conducted on 198 obese children and adolescents 6-18 years of age. Anthropometric measurements, blood pressure measurements, oral glucose tolerance test, lipid profile, and HbA1c levels of patients were assessed. Prediabetes was defined according to American Diabetes Association criteria. Left ventricular mass index (LVMi), carotid intima-media thickness (c-IMT), and tissue Doppler measurements records were used. Results: LVMi was found to be significantly higher in the prediabetes group (p=0.03). There were no statistically significant differences in right ventricular tissue Doppler measurements between the prediabetic and non-prediabetic groups. Left ventricular tissue Doppler measurements were significantly higher in the prediabetes group: LVEEM (left ventricular E/e ratio) (p=0.04); LVEM (left ventricular myocardial velocity cm/s) (p=0.035). LVMi was found to positively correlate with triglyceride level, diastolic blood pressure, waist circumference, body weight standard deviation score and to negatively correlate with high-density lipoprotein cholesterol (p=0.043, r=0.15; p=0.039, r=0.15; p=0.025, r=0.17; p=0.009, r=0.19; p=0.038, r=-0.15, respectively). LVEM was correlated with glucose (p=0.046, r=0.15) and LVEEM was correlated with systolic blood pressure (p=0.035, r=0.15). In linear regression analysis for clinical cardiovascular risk factors, fasting glucose level was the best predictor of LVEM. Conclusion: In this study, deterioration of cardiac function in prediabetic obese children and adolescents was shown. We recommend determining cardiovascular risk and cardiac dysfunction at early stages in prediabetic obese children and adolescents. PMID:26759114

  15. Prediabetes and Cardiovascular Parameters in Obese Children and Adolescents.

    Science.gov (United States)

    Eklioğlu, Beray Selver; Atabek, Mehmet Emre; Akyürek, Nesibe; Alp, Hayrullah

    2016-03-05

    In this study, our aim was to determine cardiovascular risk and cardiac function in prediabetic obese children and adolescents. The study was conducted on 198 obese children and adolescents 6-18 years of age. Anthropometric measurements, blood pressure measurements, oral glucose tolerance test, lipid profile, and HbA1c levels of patients were assessed. Prediabetes was defined according to American Diabetes Association criteria. Left ventricular mass index (LVMi), carotid intima-media thickness (c-IMT), and tissue Doppler measurements records were used. LVMi was found to be significantly higher in the prediabetes group (p=0.03). There were no statistically significant differences in right ventricular tissue Doppler measurements between the prediabetic and non-prediabetic groups. Left ventricular tissue Doppler measurements were significantly higher in the prediabetes group: LVEEM (left ventricular E/e ratio) (p=0.04); LVEM (left ventricular myocardial velocity cm/s) (p=0.035). LVMi was found to positively correlate with triglyceride level, diastolic blood pressure, waist circumference, body weight standard deviation score and to negatively correlate with high-density lipoprotein cholesterol (p=0.043, r=0.15; p=0.039, r=0.15; p=0.025, r=0.17; p=0.009, r=0.19; p=0.038, r=-0.15, respectively). LVEM was correlated with glucose (p=0.046, r=0.15) and LVEEM was correlated with systolic blood pressure (p=0.035, r=0.15). In linear regression analysis for clinical cardiovascular risk factors, fasting glucose level was the best predictor of LVEM. In this study, deterioration of cardiac function in prediabetic obese children and adolescents was shown. We recommend determining cardiovascular risk and cardiac dysfunction at early stages in prediabetic obese children and adolescents.

  16. The influence of freezing and tissue porosity on the material properties of vegetable tissues

    Energy Technology Data Exchange (ETDEWEB)

    Ralfs, Julie D

    2002-07-01

    Tissue porosity and fluid flow have been shown to be important parameters affecting the mechanical and sensorial behaviour of edible plant tissues. The quantity of fluid and the manner with which it was released on compression of the plant tissue were also important regarding the sensory perception and a good indication of any structural damage resulting from freezing, for example. Potato, carrot and Chinese water chestnut were used to study the effects freezing has on model plant tissues. Mechanical and structural measurements of the plant tissue were correlated with sensory analysis. Conventional freezing was shown to cause severe structural damage predominantly in the form of cavities between or through cells, resulting in decreases in mechanical strength and stiffness, and samples that were perceived in the mouth as 'soft' and 'wet'. The location and size of the cavities formed from ice crystals, depended on the particular plant tissue being frozen, the processing it was subjected to prior to freezing, the size of the sample and the cooling regime employed to freeze the tissue. Cavitation in the tissue resulted in an increase in tissue porosity, which enabled fluid to flow more easily from the tissue on compression, thus affecting the mechanical properties and sensory perception. Freezing damage to plant tissues was shown to be reduced, and sometimes prevented, when active antifreeze proteins (AFPs) were introduced into the tissues by vacuum infiltration or transformation and the tissue was frozen at a suitable cooling rate. Theoretical modelling was applied to the fluid flow and porosity data to test the validity of the models and to subsequently predict the mechanical behaviour of potato from the structural properties of the tissue. (author)

  17. The influence of freezing and tissue porosity on the material properties of vegetable tissues

    International Nuclear Information System (INIS)

    Ralfs, Julie D.

    2002-01-01

    Tissue porosity and fluid flow have been shown to be important parameters affecting the mechanical and sensorial behaviour of edible plant tissues. The quantity of fluid and the manner with which it was released on compression of the plant tissue were also important regarding the sensory perception and a good indication of any structural damage resulting from freezing, for example. Potato, carrot and Chinese water chestnut were used to study the effects freezing has on model plant tissues. Mechanical and structural measurements of the plant tissue were correlated with sensory analysis. Conventional freezing was shown to cause severe structural damage predominantly in the form of cavities between or through cells, resulting in decreases in mechanical strength and stiffness, and samples that were perceived in the mouth as 'soft' and 'wet'. The location and size of the cavities formed from ice crystals, depended on the particular plant tissue being frozen, the processing it was subjected to prior to freezing, the size of the sample and the cooling regime employed to freeze the tissue. Cavitation in the tissue resulted in an increase in tissue porosity, which enabled fluid to flow more easily from the tissue on compression, thus affecting the mechanical properties and sensory perception. Freezing damage to plant tissues was shown to be reduced, and sometimes prevented, when active antifreeze proteins (AFPs) were introduced into the tissues by vacuum infiltration or transformation and the tissue was frozen at a suitable cooling rate. Theoretical modelling was applied to the fluid flow and porosity data to test the validity of the models and to subsequently predict the mechanical behaviour of potato from the structural properties of the tissue. (author)

  18. A randomized, controlled, double-blind crossover study on the effects of 1-L infusions of 6% hydroxyethyl starch suspended in 0.9% saline (voluven) and a balanced solution (Plasma Volume Redibag) on blood volume, renal blood flow velocity, and renal cortical tissue perfusion in healthy volunteers.

    Science.gov (United States)

    Chowdhury, Abeed H; Cox, Eleanor F; Francis, Susan T; Lobo, Dileep N

    2014-05-01

    We compared the effects of intravenous administration of 6% hydroxyethyl starch (maize-derived) in 0.9% saline (Voluven; Fresenius Kabi, Runcorn, United Kingdom) and a "balanced" preparation of 6% hydroxyethyl starch (potato-derived) [Plasma Volume Redibag (PVR); Baxter Healthcare, Thetford, United Kingdom] on renal blood flow velocity and renal cortical tissue perfusion in humans using magnetic resonance imaging. Hyperchloremia resulting from 0.9% saline infusion may adversely affect renal hemodynamics when compared with balanced crystalloids. This phenomenon has not been studied with colloids. Twelve healthy adult male subjects received 1-L intravenous infusions of Voluven or PVR over 30 minutes in a randomized, double-blind manner, with crossover studies 7 to 10 days later. Magnetic resonance imaging proceeded for 60 minutes after commencement of infusion to measure renal artery blood flow velocity and renal cortical perfusion. Blood was sampled, and weight was recorded at 0, 30, 60, 120, 180, and 240 minutes. Mean peak serum chloride concentrations were 108 and 106 mmol/L, respectively, after Voluven and PVR infusion (P = 0.032). Changes in blood volume (P = 0.867), strong ion difference (P = 0.219), and mean renal artery flow velocity (P = 0.319) were similar. However, there was a significant increase in mean renal cortical tissue perfusion after PVR when compared with Voluven (P = 0.033). There was no difference in urinary neutrophil gelatinase-associated liopcalin to creatinine ratios after the infusion (P = 0.164). There was no difference in the blood volume-expanding properties of the 2 preparations of 6% hydroxyethyl starch. The balanced starch produced an increase in renal cortical tissue perfusion, a phenomenon not seen with starch in 0.9% saline.

  19. Erectile dysfunction in the cardiovascular patient.

    Science.gov (United States)

    Vlachopoulos, Charalambos; Jackson, Graham; Stefanadis, Christodoulos; Montorsi, Piero

    2013-07-01

    Erectile dysfunction is common in the patient with cardiovascular disease. It is an important component of the quality of life and it also confers an independent risk for future cardiovascular events. The usual 3-year time period between the onset of erectile dysfunction symptoms and a cardiovascular event offers an opportunity for risk mitigation. Thus, sexual function should be incorporated into cardiovascular disease risk assessment for all men. A comprehensive approach to cardiovascular risk reduction (comprising of both lifestyle changes and pharmacological treatment) improves overall vascular health, including sexual function. Proper sexual counselling improves the quality of life and increases adherence to medication. This review explores the critical connection between erectile dysfunction and cardiovascular disease and evaluates how this relationship may influence clinical practice. Algorithms for the management of patient with erectile dysfunction according to the risk for sexual activity and future cardiovascular events are proposed.

  20. Cardiovascular effects of air pollution.

    Science.gov (United States)

    Brook, Robert D

    2008-09-01

    Air pollution is a heterogeneous mixture of gases, liquids and PM (particulate matter). In the modern urban world, PM is principally derived from fossil fuel combustion with individual constituents varying in size from a few nanometres to 10 microm in diameter. In addition to the ambient concentration, the pollution source and chemical composition may play roles in determining the biological toxicity and subsequent health effects. Nevertheless, studies from across the world have consistently shown that both short- and long-term exposures to PM are associated with a host of cardiovascular diseases, including myocardial ischaemia and infarctions, heart failure, arrhythmias, strokes and increased cardiovascular mortality. Evidence from cellular/toxicological experiments, controlled animal and human exposures and human panel studies have demonstrated several mechanisms by which particle exposure may both trigger acute events as well as prompt the chronic development of cardiovascular diseases. PM inhaled into the pulmonary tree may instigate remote cardiovascular health effects via three general pathways: instigation of systemic inflammation and/or oxidative stress, alterations in autonomic balance, and potentially by direct actions upon the vasculature of particle constituents capable of reaching the systemic circulation. In turn, these responses have been shown to trigger acute arterial vasoconstriction, endothelial dysfunction, arrhythmias and pro-coagulant/thrombotic actions. Finally, long-term exposure has been shown to enhance the chronic genesis of atherosclerosis. Although the risk to one individual at any single time point is small, given the prodigious number of people continuously exposed, PM air pollution imparts a tremendous burden to the global public health, ranking it as the 13th leading cause of morality (approx. 800,000 annual deaths).

  1. Emotion, motivation, and cardiovascular response

    OpenAIRE

    Kreibig Sylvia D

    2012-01-01

    Cardiovascular (CV) response consists of changes in CV parameters such as heart rate blood pressure and heart contraction force in reaction to an event or set of events. It is significant for multiple reasons perhaps most notably because research suggests that it affects the development and progression of heart disease. Disease models vary but most assume that characteristically strong and prolonged CV responses confer health risk. Psychologists have long suspected linkages between motivation...

  2. Fetal Programming and Cardiovascular Pathology

    Science.gov (United States)

    Alexander, Barbara T.; Dasinger, John Henry; Intapad, Suttira

    2016-01-01

    Low birth weight serves as a crude proxy for impaired growth during fetal life and indicates a failure for the fetus to achieve its full growth potential. Low birth weight can occur in response to numerous etiologies that include complications during pregnancy, poor prenatal care, parental smoking, maternal alcohol consumption or stress. Numerous epidemiological and experimental studies demonstrate that birth weight is inversely associated with blood pressure and coronary heart disease. Sex and age impact the developmental programming of hypertension. In addition, impaired growth during fetal life also programs enhanced vulnerability to a secondary insult. Macrosomia, which occurs in response to maternal obesity, diabetes and excessive weight gain during gestation, is also associated with increased cardiovascular risk. Yet, the exact mechanisms that permanently change the structure, physiology and endocrine health of an individual across their lifespan following altered growth during fetal life are not entirely clear. Transmission of increased risk from one generation to the next in the absence of an additional prenatal insult indicates an important role for epigenetic processes. Experimental studies also indicate that the sympathetic nervous system, the renin angiotensin system, increased production of oxidative stress and increased endothelin play an important role in the developmental programming of blood pressure in later life. Thus, this review will highlight how adverse influences during fetal life and early development program an increased risk for cardiovascular disease including high blood pressure and provide an overview of the underlying mechanisms that contribute to the fetal origins of cardiovascular pathology. PMID:25880521

  3. Apolipoprotein E and cardiovascular disease

    Directory of Open Access Journals (Sweden)

    Adriana Moreno Valladares

    2006-01-01

    Full Text Available Apolipoprotein E is a polymorphic glycoprotein who interacts with the lipoprotein receptors (LRP-Receptor Related Protein and the receptors for low density lipoproteins of (LDL receptors. When lipoproteins bring up the receptors begins lipids captation and degradation which allows cholesterol utilization, taking place an intracellular auto regulation. The three isoforms of greater importance: Apo E2, E3 and E4 are product of three alleles e2, e3, e4 of one only gene. This factor is related with the amount of lipoproteins that contains ApoE for E/B receptors. A low concentration of lipoproteins with ApoE can increase the activity of LDL receptors and consequently downward the circulating LDL. In the other hand particles with Apo E3 or Apo E4, can cause a downward regulation of LDL and in this way produces a LDL plasma elevation. Many studies in human populations have concluded that this polymorphism of apoE and the plasma variation of lipoproteins are associated with cardiovascular risk. Cardiovascular disease is the result of different interaction between factors which are genetic factor specially ApoE polymorphism e4 allelic of ApoE can explain, in some degree, the greater frequency of cardiovascular disease in those who carries it.

  4. Perindopril for improving cardiovascular events

    Directory of Open Access Journals (Sweden)

    DiNicolantonio JJ

    2014-08-01

    Full Text Available James J DiNicolantonio, James H O'Keefe Department of Preventive Cardiology, Saint Luke's Mid America Heart Institute, Kansas City, MO, USAIn a recent review in Vascular Health and Risk Management Wang et al state that “In mainly placebo-controlled cardiovascular (CV-outcome studies in patients with hypertension, CV benefits with perindopril were associated with large reductions in BP.”1 However, perindopril in the European Trial on Reduction of Cardiac Events With Perindopril in Stable Coronary Artery Disease (EUROPA study significantly reduced major cardiovascular events despite a small reduction (approximately 4 mmHg in systolic blood pressure from baseline.2,3 Additionally, the average baseline blood pressure in the EUROPA was just 137/82 mmHg, and in those without hypertension, perindopril still provided a 20% reduction in the combined endpoint of cardiovascular death, myocardial infarction, and cardiac arrest.4,5 In fact, patients receiving perindopril with a baseline systolic blood pressure of <120 mmHg had the greatest reduction in the primary event.6 View original paper by Wang and colleagues. 

  5. Cardiovascular Effects of Calcium Supplements

    Directory of Open Access Journals (Sweden)

    Ian R. Reid

    2013-07-01

    Full Text Available Calcium supplements reduce bone turnover and slow the rate of bone loss. However, few studies have demonstrated reduced fracture incidence with calcium supplements, and meta-analyses show only a 10% decrease in fractures, which is of borderline statistical and clinical significance. Trials in normal older women and in patients with renal impairment suggest that calcium supplements increase the risk of cardiovascular disease. To further assess their safety, we recently conducted a meta-analysis of trials of calcium supplements, and found a 27%–31% increase in risk of myocardial infarction, and a 12%–20% increase in risk of stroke. These findings are robust because they are based on pre-specified analyses of randomized, placebo-controlled trials and are consistent across the trials. Co-administration of vitamin D with calcium does not lessen these adverse effects. The increased cardiovascular risk with calcium supplements is consistent with epidemiological data relating higher circulating calcium concentrations to cardiovascular disease in normal populations. There are several possible pathophysiological mechanisms for these effects, including effects on vascular calcification, vascular cells, blood coagulation and calcium-sensing receptors. Thus, the non-skeletal risks of calcium supplements appear to outweigh any skeletal benefits, and are they appear to be unnecessary for the efficacy of other osteoporosis treatments.

  6. Fetal programming and cardiovascular pathology.

    Science.gov (United States)

    Alexander, Barbara T; Dasinger, John Henry; Intapad, Suttira

    2015-04-01

    Low birth weight serves as a crude proxy for impaired growth during fetal life and indicates a failure for the fetus to achieve its full growth potential. Low birth weight can occur in response to numerous etiologies that include complications during pregnancy, poor prenatal care, parental smoking, maternal alcohol consumption, or stress. Numerous epidemiological and experimental studies demonstrate that birth weight is inversely associated with blood pressure and coronary heart disease. Sex and age impact the developmental programming of hypertension. In addition, impaired growth during fetal life also programs enhanced vulnerability to a secondary insult. Macrosomia, which occurs in response to maternal obesity, diabetes, and excessive weight gain during gestation, is also associated with increased cardiovascular risk. Yet, the exact mechanisms that permanently change the structure, physiology, and endocrine health of an individual across their lifespan following altered growth during fetal life are not entirely clear. Transmission of increased risk from one generation to the next in the absence of an additional prenatal insult indicates an important role for epigenetic processes. Experimental studies also indicate that the sympathetic nervous system, the renin angiotensin system, increased production of oxidative stress, and increased endothelin play an important role in the developmental programming of blood pressure in later life. Thus, this review will highlight how adverse influences during fetal life and early development program an increased risk for cardiovascular disease including high blood pressure and provide an overview of the underlying mechanisms that contribute to the fetal origins of cardiovascular pathology. © 2015 American Physiological Society.

  7. Riesgo cardiovascular, una herramienta útil para la prevención de las enfermedades cardiovasculares Cardiovascular risk, a useful tool for prevention of cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Jorge Vega Abascal

    2011-03-01

    Full Text Available El riesgo cardiovascular se define como la probabilidad de padecer un evento cardiovascular en un determinado período. Mejorar la exactitud en la predicción del riesgo requiere la evaluación y el tratamiento de múltiples factores de riesgo cardiovascular, los que tienen un efecto sinérgico, más que aditivo, sobre el riesgo cardiovascular total. El cálculo utilizando métodos cuantitativos es más preciso que el obtenido con métodos cualitativos. La predicción del riesgo cardiovascular ha constituido, en los últimos años, la piedra angular en las guías clínicas de prevención cardiovascular, y deviene una herramienta útil del Médico de Familia para establecer prioridades en la atención primaria, mejorando la atención a los pacientes y eligiendo más eficazmente la terapéutica a seguir, con el objetivo de acercarnos más a la realidad multifactorial de las enfermedades cardiovasculares y a su prevención.The cardiovascular risk is defined like a probability of suffering a cardiovascular event in a determined period. To improve the accuracy in risk prediction requires the assessment and treatment of different cardiovascular risk factors, which have a synergistic effect more than additive on the total cardiovascular risk. The calculus using quantitative methods is more accurate than that obtained with qualitative methods. The prediction of cardiovascular risk has been in past years the cornerstone in clinical guidances of cardiovascular prevention and becomes an useful tool for Family Physician to establish priorities in the primary care, improving the patients care and selecting in a more effective way the therapy to be followed to bring closer more to multifactor reality of cardiovascular diseases and its prevention.

  8. Adipocytokines, C-reactive protein, and cardiovascular disease

    DEFF Research Database (Denmark)

    Seven, Ekim; Husemoen, Lise L N; Sehested, Thomas S G

    2015-01-01

    BACKGROUND: Being overweight or obese is associated with a greater risk of coronary heart disease and stroke compared with normal weight. The role of the specific adipose tissue-derived substances, called adipocytokines, in overweight- and obesity-related cardiovascular disease (CVD) is still...... defined a composite outcome comprising of the first event of fatal and nonfatal coronary heart disease and fatal and nonfatal stroke. RESULTS: During the follow-up period, 453 composite CV outcomes occurred among participants with complete datasets. In models, including gender, age, smoking status...

  9. 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.

  10. Computational medical imaging and hemodynamics framework for functional analysis and assessment of cardiovascular structures.

    Science.gov (United States)

    Wong, Kelvin K L; Wang, Defeng; Ko, Jacky K L; Mazumdar, Jagannath; Le, Thu-Thao; Ghista, Dhanjoo

    2017-03-21

    Cardiac dysfunction constitutes common cardiovascular health issues in the society, and has been an investigation topic of strong focus by researchers in the medical imaging community. Diagnostic modalities based on echocardiography, magnetic resonance imaging, chest radiography and computed tomography are common techniques that provide cardiovascular structural information to diagnose heart defects. However, functional information of cardiovascular flow, which can in fact be used to support the diagnosis of many cardiovascular diseases with a myriad of hemodynamics performance indicators, remains unexplored to its full potential. Some of these indicators constitute important cardiac functional parameters affecting the cardiovascular abnormalities. With the advancement of computer technology that facilitates high speed computational fluid dynamics, the realization of a support diagnostic platform of hemodynamics quantification and analysis can be achieved. This article reviews the state-of-the-art medical imaging and high fidelity multi-physics computational analyses that together enable reconstruction of cardiovascular structures and hemodynamic flow patterns within them, such as of the left ventricle (LV) and carotid bifurcations. The combined medical imaging and hemodynamic analysis enables us to study the mechanisms of cardiovascular disease-causing dysfunctions, such as how (1) cardiomyopathy causes left ventricular remodeling and loss of contractility leading to heart failure, and (2) modeling of LV construction and simulation of intra-LV hemodynamics can enable us to determine the optimum procedure of surgical ventriculation to restore its contractility and health This combined medical imaging and hemodynamics framework can potentially extend medical knowledge of cardiovascular defects and associated hemodynamic behavior and their surgical restoration, by means of an integrated medical image diagnostics and hemodynamic performance analysis framework.

  11. Electromechanical Model of Blood Flow in Vessels

    OpenAIRE

    Ivo Cap; Barbora Czippelova

    2008-01-01

    The present paper deals with some theoretical derivations connected with very efficient method of solution of hydrodynamic problems of blood flow in human cardiovascular system. The electromechanical analogy of liquid flow in a tube and electromagnetic wave propagating along an electric transmission line is discussed. We have derived a detailed circuit-like model of an elementary section of the elastic tube with viscose Newtonian liquid. The analogy harmonic current electrical cir...

  12. Electromechanical Model of Blood Flow in Vessels

    Directory of Open Access Journals (Sweden)

    Ivo Cap

    2008-01-01

    Full Text Available The present paper deals with some theoretical derivations connected with very efficient method of solution of hydrodynamic problems of blood flow in human cardiovascular system. The electromechanical analogy of liquid flow in a tube and electromagnetic wave propagating along an electric transmission line is discussed. We have derived a detailed circuit-like model of an elementary section of the elastic tube with viscose Newtonian liquid. The analogy harmonic current electrical circuit has been designed

  13. Cardiovascular magnetic resonance in pericardial diseases

    Directory of Open Access Journals (Sweden)

    Francone Marco

    2009-05-01

    Full Text Available Abstract The pericardium and pericardial diseases in particular have received, in contrast to other topics in the field of cardiology, relatively limited interest. Today, despite improved knowledge of pathophysiology of pericardial diseases and the availability of a wide spectrum of diagnostic tools, the diagnostic challenge remains. Not only the clinical presentation may be atypical, mimicking other cardiac, pulmonary or pleural diseases; in developed countries a shift for instance in the epidemiology of constrictive pericarditis has been noted. Accurate decision making is crucial taking into account the significant morbidity and mortality caused by complicated pericardial diseases, and the potential benefit of therapeutic interventions. Imaging herein has an important role, and cardiovascular magnetic resonance (CMR is definitely one of the most versatile modalities to study the pericardium. It fuses excellent anatomic detail and tissue characterization with accurate evaluation of cardiac function and assessment of the haemodynamic consequences of pericardial constraint on cardiac filling. This review focuses on the current state of knowledge how CMR can be used to study the most common pericardial diseases.

  14. Lipoprotein(a in Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Michele Malaguarnera

    2013-01-01

    Full Text Available Lipoprotein(a (Lp(a is an LDL-like molecule consisting of an apolipoprotein B-100 (apo(B-100 particle attached by a disulphide bridge to apo(a. Many observations have pointed out that Lp(a levels may be a risk factor for cardiovascular diseases. Lp(a inhibits the activation of transforming growth factor (TGF and contributes to the growth of arterial atherosclerotic lesions by promoting the proliferation of vascular smooth muscle cells and the migration of smooth muscle cells to endothelial cells. Moreover Lp(a inhibits plasminogen binding to the surfaces of endothelial cells and decreases the activity of fibrin-dependent tissue-type plasminogen activator. Lp(a may act as a proinflammatory mediator that augments the lesion formation in atherosclerotic plaques. Elevated serum Lp(a is an independent predictor of coronary artery disease and myocardial infarction. Furthermore, Lp(a levels should be a marker of restenosis after percutaneous transluminal coronary angioplasty, saphenous vein bypass graft atherosclerosis, and accelerated coronary atherosclerosis of cardiac transplantation. Finally, the possibility that Lp(a may be a risk factor for ischemic stroke has been assessed in several studies. Recent findings suggest that Lp(a-lowering therapy might be beneficial in patients with high Lp(a levels. A future therapeutic approach could include apheresis in high-risk patients in order to reduce major coronary events.

  15. Nitric oxide and cardiovascular risk factors

    Directory of Open Access Journals (Sweden)

    Livio Dai Cas

    2007-06-01

    Full Text Available The endothelium is a dynamic organ with many properties that takes part in the regulation of the principal mechanisms of vascular physiology. Its principal functions include the control of blood-tissue exchange and permeability, the vascular tonus, and the modulation of inflammatory or coagulatory mechanisms. Many vasoactive molecules, produced by the endothelium, are involved in the control of these functions. The most important is nitric oxide (NO, a gaseous molecule electrically neutral with an odd number of electrons that gives the molecule chemically reactive radical properties. Already known in the twentieth century, NO, sometimes considered as a dangerous molecule, recently valued as an important endogenous vasodilator factor. Recently, it was discovered that it is involved in several physiological mechanisms of endothelial protection (Tab. I. In 1992, Science elected it as “molecule of the year”; 6 yrs later three American researchers (Louis Ignarro, Robert Furchgott and Fried Murad obtained a Nobel Prize for Medicine and Physiology “for their discoveries about NO as signal in the cardiovascular system”.

  16. Microsurgical Composite Tissue Transplantation

    Science.gov (United States)

    Serafin, Donald; Georgiade, Nicholas G.

    1978-01-01

    Since 1974, 69 patients with extensive defects have undergone reconstruction by microsurgical composite tissue transplantation. Using this method, donor composite tissue is isolated on its blood supply, removed to a distant recipient site, and the continuity of blood flow re-established by microvascular anastomoses. In this series, 56 patients (81%) were completely successful. There have been eight (12%) failures, primarily in the extremities. There have been five (7%) partial successes, (i.e., a microvascular flap in which a portion was lost requiring a secondary procedure such as a split thickness graft). In those patients with a severely injured lower extremity, the failure rate was the greatest. Most of these were arterial (six of seven). These failures occurred early in the series and were thought to be related to a severely damaged recipient vasculature. This problem has been circumvented by an autogenous interpositional vein graft, permitting more mobility of flap placement. In the upper extremity, all but one case were successful. Early motion was permitted, preventing joint capsular contractures and loss of function. Twenty-three cases in the head and neck region were successful (one partial success). This included two composite rib grafts to the mandible. Prolonged delays in reconstruction following extirpation of a malignancy were avoided. A rapid return to society following complete reconstruction was ensured. Nine patients presented for reconstruction of the breast and thorax following radical mastectomy. All were successfully reconstructed with this new technique except one patient. Its many advantages include immediate reconstruction without delayed procedures and no secondary deformity of the donor site. Healthy, well vascularized tissue can now be transferred to a previously irradiated area with no tissue loss. This new method offers many advantages to older methods of reconstruction. Length of hospital stay and immobilization are reduced. The

  17. Rotating flow

    CERN Document Server

    Childs, Peter R N

    2010-01-01

    Rotating flow is critically important across a wide range of scientific, engineering and product applications, providing design and modeling capability for diverse products such as jet engines, pumps and vacuum cleaners, as well as geophysical flows. Developed over the course of 20 years' research into rotating fluids and associated heat transfer at the University of Sussex Thermo-Fluid Mechanics Research Centre (TFMRC), Rotating Flow is an indispensable reference and resource for all those working within the gas turbine and rotating machinery industries. Traditional fluid and flow dynamics titles offer the essential background but generally include very sparse coverage of rotating flows-which is where this book comes in. Beginning with an accessible introduction to rotating flow, recognized expert Peter Childs takes you through fundamental equations, vorticity and vortices, rotating disc flow, flow around rotating cylinders and flow in rotating cavities, with an introduction to atmospheric and oceanic circul...

  18. [Cardiovascular resistance to orthostatic stress in athletes after aerobic exercise].

    Science.gov (United States)

    Mel'nikov, A A; Popov, S G; Vikulov, A D

    2014-01-01

    In the paper cardiovascular resistance to orthostatic stress in the athletes in the two-hour recovery period after prolonged aerobic exercise was investigated. The reaction of the cardiac (stroke volume and cardiac output) and peripheral blood volumes in the lower and upper limbs, abdominal and neck regions in response to the tilt-test before and during two hours after exercise (30 min, heart rate = 156 +/- 8 beats/min) was determined by impedance method: It is found that: (1) at baseline distribution of blood flow in favor of the neck-region in response to the tilt-test, in spite of the decrease in cardiac output, was more efficient in athletes, that was due to a large decrease in blood flow to the lower extremities, and increased blood flow in the neck region; (2) after exercise it was established symptoms of potential orthostatic intolerance: postural hypotension and tachycardia, reduced peripheral pulse blood volume, expressed in a standing position, and reduced effectiveness of the distribution of blood flow in the direction of the neck region; (3) the abilityto effectively distribute blood flow in favor of the neck region in athletes after exercise remained elevated, which was due to a large decrease in blood flow in the abdominal region at the beginning, and in the lower limbs at the end of the recovery period.

  19. Mixed Connective Tissue Disease

    Science.gov (United States)

    Mixed connective tissue disease Overview Mixed connective tissue disease has signs and symptoms of a combination of disorders — primarily lupus, scleroderma and polymyositis. For this reason, mixed connective tissue disease ...

  20. Undifferentiated Connective Tissue Disease

    Science.gov (United States)

    ... Home Conditions Undifferentiated Connective Tissue Disease (UCTD) Undifferentiated Connective Tissue Disease (UCTD) Make an Appointment Find a Doctor ... by Barbara Goldstein, MD (February 01, 2016) Undifferentiated connective tissue disease (UCTD) is a systemic autoimmune disease. This ...

  1. Soft Tissue Sarcoma

    Science.gov (United States)

    ... muscles, tendons, fat, and blood vessels. Soft tissue sarcoma is a cancer of these soft tissues. There ... have certain genetic diseases. Doctors diagnose soft tissue sarcomas with a biopsy. Treatments include surgery to remove ...

  2. 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

  3. AT2 Receptor and Tissue Injury

    DEFF Research Database (Denmark)

    Namsolleck, Pawel; Recarti, Chiara; Foulquier, Sébastien

    2014-01-01

    The renin-angiotensin system (RAS) plays an important role in the initiation and progression of tissue injuries in the cardiovascular and nervous systems. The detrimental actions of the AT1 receptor (AT1R) in hypertension and vascular injury, myocardial infarction and brain ischemia are well...... established. In the past twenty years, protective actions of the RAS, not only in the cardiovascular, but also in the nervous system, have been demonstrated. The so-called protective arm of the RAS includes AT2-receptors and Mas receptors (AT2R and MasR) and is characterized by effects different from...... and often opposing those of the AT1R. These include anti-inflammation, anti-fibrosis, anti-apoptosis and neuroregeneration that can counterbalance pathological processes and enable recovery from disease. The recent development of novel, small-molecule AT2R agonists offers a therapeutic potential in humans...

  4. The use of soft robotics in cardiovascular therapy.

    Science.gov (United States)

    Wamala, Isaac; Roche, Ellen T; Pigula, Frank A

    2017-10-01

    Robots have been employed in cardiovascular therapy as surgical tools and for automation of hospital systems. Soft robots are a new kind of robot made of soft deformable materials, that are uniquely suited for biomedical applications because they are inherently less likely to injure body tissues and more likely to adapt to biological environments. Awareness of the soft robotic systems under development will help promote clinician involvement in their successful clinical translation. Areas covered: The most advanced soft robotic systems, across the size scale from nano to macro, that have shown the most promise for clinical application in cardiovascular therapy because they offer solutions where a clear therapeutic need still exists. We discuss nano and micro scale technology that could help improve targeted therapy for cardiac regeneration in ischemic heart disease, and soft robots for mechanical circulatory support. Additionally, we suggest where the gaps in the technology currently lie. Expert commentary: Soft robotic technology has now matured from the proof-of-concept phase to successful animal testing. With further refinement in materials and clinician guided application, they will be a useful complement for cardiovascular therapy.

  5. The role of urocortins in the cardiovascular system.

    Science.gov (United States)

    Walczewska, J; Dzieza-Grudnik, A; Siga, O; Grodzicki, T

    2014-12-01

    Urocortins (Ucn) 1, 2 and 3 are a group of endogenous peptide hormones belonging to the corticotropin-releasing hormone (CRH) family of peptides. The presence of urocortins has been detected in the central nervous system as well as in peripheral tissues. They play an important role in a stress response (with respect to its duration, intensity and restoration of homeostasis). They also act as regulatory factors of the cardiovascular, gastrointestinal, reproductive and immune systems. Urocortins act by binding to G-protein-coupled receptors (GPCR). The "central" effects of urocortins are mediated mainly by activation of CRH receptor 1 (CRH-R1), and the "peripheral" effects by activation of CRH-R2. Ucn2 and Ucn3 are selective CRH-R2 agonists and have much higher binding affinity to this receptor than CRH and Ucn1. Recent studies have shown that urocortins exert various biological effects in the cardiovascular system, such as vasodilation, positive inotropic and lusitropic effects, as well as cardioprotection against ischemia-reperfusion injury. They also suppress the renin-angiotensin system and may have an impact on the sympathetic nervous system. Urocortins and CRH-R2 may be a potential therapeutic target in coronary heart disease, congestive heart failure and hypertension. This review summarizes the data published to date on the role of urocortins in the cardiovascular system.

  6. The effects of age on the spontaneous low-frequency oscillations in cerebral and systemic cardiovascular dynamics

    International Nuclear Information System (INIS)

    Peng, Tingying; Rowley, Alex B; Payne, Stephen J; Ainslie, Philip N; Murrell, Carissa; Thomas, Kate; Cotter, James D; Williams, Michael J A; George, Keith; Shave, Rob

    2008-01-01

    Although the effects of ageing on cardiovascular control and particularly the response to orthostatic stress have been the subject of many studies, the interaction between the cardiovascular and cerebral regulation mechanisms is still not fully understood. Wavelet cross-correlation is used here to assess the coupling and synchronization between low-frequency oscillations (LFOs) observed in cerebral hemodynamics, as measured using cerebral blood flow velocity (CBFV) and cerebral oxygenation (O 2 Hb), and systemic cardiovascular dynamics, as measured using heart rate (HR) and arterial blood pressure (ABP), in both old and young healthy subjects undergoing head-up tilt table testing. Statistically significant increases in correlation values are found in the interaction of cerebral and cardiovascular LFOs for young subjects (P 2 Hb and ABP–O 2 Hb), but not in old subjects under orthostatic stress. The coupling between the cerebrovascular and wider cardiovascular systems in response to orthostatic stress thus appears to be impaired with ageing

  7. Amplatzer vascular plugs in congenital cardiovascular malformations

    International Nuclear Information System (INIS)

    Barwad, Parag; Ramakrishnan, Sivasubramanian; Kothari, Shyam S; Saxena, Anita; Gupta, Saurabh K; Juneja, Rajnish; Gulati, Gurpreet Singh; Jagia, Priya; Sharma, Sanjiv

    2013-01-01

    Amplatzer vascular plugs (AVPs) are devices ideally suited to close medium-to-large vascular communications. There is limited published literature regarding the utility of AVPs in congenital cardiovascular malformations (CCVMs). To describe the use of AVPs in different CCVMs and to evaluate their safety and efficacy. All patients who required an AVP for the closure of CCVM were included in this retrospective review of our catheterization laboratory data. The efficacy and safety of AVPs are reported. A total of 39 AVPs were implanted in 31 patients. Thirteen (33%) were AVP type I and 23 (59%) were AVP type II. AVP type III were implanted in two patients and type IV in one patient. The major indications for their use included closure of pulmonary arteriovenous malformation (AVM) (n = 7), aortopulmonary collaterals (n = 7), closure of a patent Blalock-Taussig shunt (n = 5), systemic AVM (n = 5), coronary AVM (n = 4), patent ductus arteriosus (PDA) (n = 3), pulmonary artery aneurysms (n = 3), and venovenous collaterals (n = 2). Deployment of the AVP was done predominantly via the 5 – 7F Judkin's right coronary guide catheter. Overall 92% of the AVPs could be successfully deployed and resulted in occlusion of the target vessel in all cases, within 10 minutes. No procedure-related or access site complication occurred. AVPs are versatile, easy to use, and effective devices to occlude the vascular communications in a variety of settings. AVP II is especially useful in the closure of tubular structures with a high flow

  8. The Emerging Role of TLR and Innate Immunity in Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Rolf Spirig

    2012-01-01

    Full Text Available Cardiovascular disease is a complex disorder involving multiple pathophysiological processes, several of which involve activation of toll-like receptors (TLRs of the innate immune system. As sentinels of innate immunity TLRs are nonclonally germline-encoded molecular pattern recognition receptors that recognize exogenous as well as tissue-derived molecular dangers signals promoting inflammation. In addition to their expression in immune cells, TLRs are found in other tissues and cell types including cardiomyocytes, endothelial and vascular smooth muscle cells. TLRs are differentially regulated in various cell types by several cardiovascular risk factors such as hypercholesterolemia, hyperlipidemia, and hyperglycemia and may represent a key mechanism linking chronic inflammation, cardiovascular disease progression, and activation of the immune system. Modulation of TLR signaling by specific TLR agonists or antagonists, alone or in combination, may be a useful therapeutic approach to treat various cardiovascular inflammatory conditions such as atherosclerosis, peripheral arterial disease, secondary microvascular complications of diabetes, autoimmune disease, and ischemia reperfusion injury. In this paper we discuss recent developments and current evidence for the role of TLR in cardiovascular disease as well as the therapeutic potential of various compounds on inhibition of TLR-mediated inflammatory responses.

  9. A role for collagen IV in cardiovascular disease?

    DEFF Research Database (Denmark)

    Steffensen, Lasse Bach; Rasmussen, Lars M

    2018-01-01

    Over the past decade, studies have repeatedly found single nucleotide polymorphisms located in the COL4A1 and COL4A2 genes to be associated with cardiovascular disease (CVD), and the 13q34 locus harboring these genes is one of approximately 160 genome-wide significant risk loci for coronary artery...... disease. COL4A1 and COL4A2 encode the ⍺1- and ⍺2-chains of collagen IV, a major component of basement membranes in various tissues including arteries. In spite of the growing body of evidence indicating a role for collagen IV in CVD, remarkably few studies aim at directly investigating such a role....... The purpose of this review is to summarize the clinical reports linking 13q34 to coronary artery disease, atherosclerosis and artery stiffening and to assemble the scattered pieces of evidence from experimental studies based on vascular cells and -tissue collectively supporting a role for collagen IV...

  10. Flow regimes

    International Nuclear Information System (INIS)

    Kh'yuitt, G.

    1980-01-01

    An introduction into the problem of two-phase flows is presented. Flow regimes arizing in two-phase flows are described, and classification of these regimes is given. Structures of vertical and horizontal two-phase flows and a method of their identification using regime maps are considered. The limits of this method application are discussed. The flooding phenomena and phenomena of direction change (flow reversal) of the flow and interrelation of these phenomena as well as transitions from slug regime to churn one and from churn one to annular one in vertical flows are described. Problems of phase transitions and equilibrium are discussed. Flow regimes in tubes where evaporating liquid is running, are described [ru

  11. Oxidative stress in cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Shyamal K Goswami

    2015-01-01

    Full Text Available Oxidative stress caused by various oxygen containing free radicals and reactive species (collectively called "Reactive Oxygen Species" or ROS has long been attributed to cardiovascular diseases. In human body, major oxidizing species are super oxide, hydrogen peroxide, hydroxyl radical, peroxy nitrite etc. ROS are produced from distinct cellular sources, enzymatic and non-enzymatic; have specific physicochemical properties and often have specific cellular targets. Although early studies in nineteen sixties and seventies highlighted the deleterious effects of these species, later it was established that they also act as physiological modulators of cellular functions and diseases occur only when ROS production is deregulated. One of the major sources of cellular ROS is Nicotinamide adenine dinucleotide phosphate oxidases (Noxes that are expressed in almost all cell types. Superoxide and hydrogen peroxide generated from them under various conditions act as signal transducers. Due to their immense importance in cellular physiology, various Nox inhibitors are now being developed as therapeutics. Another free radical of importance in cardiovascular system is nitric oxide (a reactive nitrogen species generated from nitric oxide synthase(s. It plays a critical role in cardiac function and its dysregulated generation along with superoxide leads to the formation of peroxynitrite a highly deleterious agent. Despite overwhelming evidences of association between increased level of ROS and cardiovascular diseases, antioxidant therapies using vitamins and omega 3 fatty acids have largely been unsuccessful till date. Also, there are major discrepancies between studies with laboratory animals and human trials. It thus appears that the biology of ROS is far complex than anticipated before. A comprehensive understanding of the redox biology of diseases is thus needed for developing targeted therapeutics.

  12. Cardiovascular screening in Turner syndrome

    International Nuclear Information System (INIS)

    Dawson, K.L.; Wright, A.M.; Pitlick, P.T.

    1990-01-01

    This paper determines the utility of MR imaging as a cardiovascular screening method in patients with Turner syndrome and to compare its utility with that of echocardiography. Forty females with karytotypically proved Turner syndrome were prospectively evaluated with MR imaging and echocardiography. A 0.38-T resistive magnet was used to obtain ECG-gated axial and off-sagittal oblique images through the thorax with a spin-echo pulse sequence and TR 400--600 msec, TE 15--30 msec. Two-dimensional, M-mode, and Doppler echocardiography were performed and standard echocardiographic views were obtained

  13. Cell Therapy in Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Hoda Madani

    2014-05-01

    Full Text Available   Recently, cell therapy has sparked a revolution in ischemic heart disease that will in the future help clinicians to cure patients. Earlier investigations in animal models and clinical trials have suggested that positive paracrine effects such as neoangiogenesis and anti-apoptotic can improve myocardial function. In this regard the Royan cell therapy center designed a few trials in collaboration with multi hospitals such as Baqiyatallah, Shahid Lavasani, Tehran Heart Center, Shahid rajaee, Masih daneshvari, Imam Reza, Razavi and Sasan from 2006. Their results were interesting. However, cardiac stem cell therapy still faces great challenges in optimizing the treatment of patients. Keyword: Cardiovascular disease, Cell therapy.  

  14. Dynamic interactions between musical, cardiovascular, and cerebral rhythms in humans.

    Science.gov (United States)

    Bernardi, Luciano; Porta, Cesare; Casucci, Gaia; Balsamo, Rossella; Bernardi, Nicolò F; Fogari, Roberto; Sleight, Peter

    2009-06-30

    Reactions to music are considered subjective, but previous studies suggested that cardiorespiratory variables increase with faster tempo independent of individual preference. We tested whether compositions characterized by variable emphasis could produce parallel instantaneous cardiovascular/respiratory responses and whether these changes mirrored music profiles. Twenty-four young healthy subjects, 12 musicians (choristers) and 12 nonmusician control subjects, listened (in random order) to music with vocal (Puccini's "Turandot") or orchestral (Beethoven's 9th Symphony adagio) progressive crescendos, more uniform emphasis (Bach cantata), 10-second period (ie, similar to Mayer waves) rhythmic phrases (Giuseppe Verdi's arias "Va pensiero" and "Libiam nei lieti calici"), or silence while heart rate, respiration, blood pressures, middle cerebral artery flow velocity, and skin vasomotion were recorded.Common responses were recognized by averaging instantaneous cardiorespiratory responses regressed against changes in music profiles and by coherence analysis during rhythmic phrases. Vocal and orchestral crescendos produced significant (P=0.05 or better) correlations between cardiovascular or respiratory signals and music profile, particularly skin vasoconstriction and blood pressures, proportional to crescendo, in contrast to uniform emphasis, which induced skin vasodilation and reduction in blood pressures. Correlations were significant both in individual and group-averaged signals. Phrases at 10-second periods by Verdi entrained the cardiovascular autonomic variables. No qualitative differences in recorded measurements were seen between musicians and nonmusicians. Music emphasis and rhythmic phrases are tracked consistently by physiological variables. Autonomic responses are synchronized with music, which might therefore convey emotions through autonomic arousal during crescendos or rhythmic phrases.

  15. E-cigarettes and cardiovascular risk: beyond science and mysticism.

    Science.gov (United States)

    Lippi, Giuseppe; Favaloro, Emmanuel J; Meschi, Tiziana; Mattiuzzi, Camilla; Borghi, Loris; Cervellin, Gianfranco

    2014-02-01

    Cigarette smoking is the most important cause of premature death, and it is currently listed as a major independent risk factor for cardiovascular disease. Because of restrictive measures and widespread control policies, tobacco companies are now using aggressive marketing strategies in favor of smokeless tobacco, including electronic nicotine delivery systems, which are also known as electronic cigarettes or e-cigarettes. Although the regular use of these devices appears less hazardous than traditional cigarettes or other forms of smokeless tobacco, recent studies have shown that various potentially harmful substances, especially nicotine, ultraparticles, and volatile organic compounds, may be effectively inhaled or liberated in exhaled air during repeated e-cigarette puffing. This would enhance the risk of cardiac arrhythmias and hypertension, which may predispose some users to increased risk of cardiovascular events, which may be further magnified by other potential adverse effects such as arrhythmias, increased respiratory, and flow respiratory resistance. Some cases of intoxication have also been described, wherein large amounts of nicotine and other harmful compounds may be effectively absorbed. As the use of e-cigarettes is continuously rising, and it is also considered a potentially effective method for smoking cessation, more focused research is urgently needed to definitely establish the cardiovascular safeness of these devices. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  16. Prevalence of stroke/cardiovascular risk factors in Hungary

    Science.gov (United States)

    Bodo, M.; Sipos, K.; Thuroczy, G.; Panczel, G.; Ilias, L.; Szonyi, P.; Bodo, M., Jr.; Nebella, T.; Banyasz, A.; Nagy, Z.

    2010-04-01

    A cross-sectional survey was conducted in Hungary using the Cerberus system which includes: 1) a questionnaire addressing the risk factors for stroke/cardiovascular disease; 2) amplifiers to record the pulse waves of cerebral arteries (rheoencephalography) and peripheral arteries, electrocardiogram and electroencephalogram. Additionally, subjects were measured for carotid stenosis by Doppler ultrasound and 12-lead electrocardiogram; subjects were also screened for blood cholesterol, glucose, and triglyceride levels. Prevalence of the following stroke risk factors was identified: overweight, 63.25%; sclerotic brain arteries (by rheoencephalogram), 54.29%; heart disease, 37.92%; pathologic carotid flow, 34.24%; smoking, 30.55%; high blood cholesterol, 28.70%; hypertension, 27.83%; high triglyceride, 24.35%; abnormality in electrocardiogram, 20%; high glucose, 15.95%; symptoms of transient ischemic attack, 16.07%; alcohol abuse, 6.74%; and diabetes, 4.53%. The study demonstrates a possible model for primary cardiovascular disease/stroke prevention. This method offers a standardizable, cost effective, practical technique for mass screenings by identifying the population at high risk for cardiovascular disturbances, especially cerebrovascular disease (primary prevention). In this model, the rheoencephalogram can detect cerebrovascular arteriosclerosis in the susceptibility/presymptomatic phase, earlier than the Doppler ultrasound technique. The method also provides a model for storing analog physiological signals in a computer-based medical record and is a first step in applying an expert system to stroke prevention.

  17. Evaluation of the cardiovascular effects of varenicline in rats

    Directory of Open Access Journals (Sweden)

    Selçuk EB

    2015-10-01

    prolongation was statistically significant in both the control and acute varenicline groups. Caspase-9 activity was also significantly increased by chronic exposure. Moreover, histopathological observations revealed severe morphological heart damage in both groups.Conclusion: Adverse effects of chronic varenicline exposure on cardiovascular tissue were confirmed by our electrocardiographic, biochemical, and histopathological analyses. This issue needs to be investigated with new experimental and clinical studies to evaluate the exact mechanism(s of the detrimental effects of varenicline. Physicians should bear in mind the toxic effects of varenicline on the cardiovascular system when prescribing it for smoking cessation.Keywords: varenicline, smoking, cardiovascular, rat, electrocardiogram, histopathological evaluation

  18. Influenza vaccines for preventing cardiovascular disease

    OpenAIRE

    Clar,Christine; Oseni,Zainab; Flowers,Nadine; Keshtkar-Jahromi,Maryam; Rees,Karen

    2015-01-01

    ABSTRACTBACKGROUND: This is an update of the original review published in 2008. The risk of adverse cardiovascular outcomes is increased with influenza-like infection, and vaccination against influenza may improve cardiovascular outcomes.OBJECTIVES: To assess the potential benefits of influenza vaccination for primary and secondary prevention of cardiovascular disease.METHODS:Search methods:We searched the following electronic databases on 18 October 2013: The Cochrane Library (including Coch...

  19. Tissue engineered tumor models.

    Science.gov (United States)

    Ingram, M; Techy, G B; Ward, B R; Imam, S A; Atkinson, R; Ho, H; Taylor, C R

    2010-08-01

    Many research programs use well-characterized tumor cell lines as tumor models for in vitro studies. Because tumor cells grown as three-dimensional (3-D) structures have been shown to behave more like tumors in vivo than do cells growing in monolayer culture, a growing number of investigators now use tumor cell spheroids as models. Single cell type spheroids, however, do not model the stromal-epithelial interactions that have an important role in controlling tumor growth and development in vivo. We describe here a method for generating, reproducibly, more realistic 3-D tumor models that contain both stromal and malignant epithelial cells with an architecture that closely resembles that of tumor microlesions in vivo. Because they are so tissue-like we refer to them as tumor histoids. They can be generated reproducibly in substantial quantities. The bioreactor developed to generate histoid constructs is described and illustrated. It accommodates disposable culture chambers that have filled volumes of either 10 or 64 ml, each culture yielding on the order of 100 or 600 histoid particles, respectively. Each particle is a few tenths of a millimeter in diameter. Examples of histological sections of tumor histoids representing cancers of breast, prostate, colon, pancreas and urinary bladder are presented. Potential applications of tumor histoids include, but are not limited to, use as surrogate tumors for pre-screening anti-solid tumor pharmaceutical agents, as reference specimens for immunostaining in the surgical pathology laboratory and use in studies of invasive properties of cells or other aspects of tumor development and progression. Histoids containing nonmalignant cells also may have potential as "seeds" in tissue engineering. For drug testing, histoids probably will have to meet certain criteria of size and tumor cell content. Using a COPAS Plus flow cytometer, histoids containing fluorescent tumor cells were analyzed successfully and sorted using such criteria.

  20. Regional blood flow in the domestic fowl immediately following chronic acceleration

    International Nuclear Information System (INIS)

    Weidner, W.J.; Hoffman, L.F.; Clark, S.D.

    1982-01-01

    In order to examine the effects of chronic low G acceleration on blood flow distribution and cardiac output, chickens (N.10) were centrifuged at +2Gz for 30-61 d. Controls (N.12) were not centrifuged. The animals were anesthetized with sodium pentobarbital after removal from the centrifuge and surgically prepared in order to measure cardiac output and regional blood flows by the reference sample method with 85 Sr labeled microspheres (15 +/- 5 mum diam.). Both brachial arteries were cannulated to withdraw timed, paired blood samples at a known rate. The chest was opened and a cannula inserted into the left ventricle for administration of microspheres. Tissue samples were taken after completion of experimental procedures and their radioactivity was determined. The cardiac outputs in the two groups were not significantly different. Regional blood flows to the kidney, eyes, and skeletal muscle were significantly increased in the animals subjected to chronic +2Gz. While the mechanism by which these increases in blood flow occurred is not known, results indicate that chronic exposure to hyperdynamic gravitational fields can alter circulatory dynamics. We conclude that the cardiovascular system is directly involved in the process of adaptation to chronic positive acceleration