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Sample records for peripheral vascular function

  1. Massage Therapy Restores Peripheral Vascular Function following Exertion

    PubMed Central

    Franklin, Nina C.; Ali, Mohamed M.; Robinson, Austin T.; Norkeviciute, Edita; Phillips, Shane A.

    2014-01-01

    Objective To determine if lower extremity exercise-induced muscle injury (EMI) reduces vascular endothelial function of the upper extremity and if massage therapy (MT) improves peripheral vascular function after EMI. Design Randomized, blinded trial with evaluations at 90 minutes, 24 hours, 48 hours, and 72 hours. Setting Clinical research center at an academic medical center and laboratory Participants Thirty-six sedentary young adults were randomly assigned to one of three groups: 1) EMI + MT (n=15; mean age ± standard error (SE): 26.6±0.3), 2) EMI only (n=10; mean age ± SE: 23.6±0.4), and 3) MT only (n=11; mean age ± SE: 25.5 ± 0.4). Intervention Participants were assigned to either EMI only (a single bout of bilateral, eccentric leg-press exercise), MT only (30-minute lower extremity massage using Swedish technique), or EMI + MT. Main outcome measures Brachial artery flow-mediated dilation (FMD) was determined by ultrasound at each time point. Nitroglycerin-induced dilation was also assessed (NTG; 0.4 mg). Results Brachial FMD increased from baseline in the EMI + MT group and the MT only group (7.38±0.18 to 9.02±0.28%, p<0.05 and 7.77±0.25 to 10.20±0.22%, p < 0.05, respectively) at 90 minutes remaining elevated until 72 hrs. In the EMI only group FMD was reduced from baseline at 24 and 48 hrs (7.78±0.14 to 6.75±0.11%, p<0.05 and 6.53±0.11, p<0.05, respectively) returning to baseline after 72 hrs. Dilations to NTG were similar over time. Conclusions Our results suggest that MT attenuates impairment of upper extremity endothelial function resulting from lower extremity EMI in sedentary young adults. PMID:24583315

  2. Association Between Peripheral Vascular Endothelial Function and Progression of Open-Angle Glaucoma.

    PubMed

    Liu, Chun-Hsiu; Su, Wei-Wen; Shie, Shian-Sen; Cheng, Shih-Tsung; Su, Cheng-Wen; Ho, Wang-Jing

    2016-03-01

    The aim of the study is to evaluate the relationship between Humphrey visual field progression and peripheral vascular endothelial function in patients with open-angle glaucoma (OAG), assessed by noninvasive endothelium-dependent flow-mediated vasodilation (FMD).Forty OAG patients, among which 22 had normal-tension glaucoma (NTG) and 18 had primary open-angle glaucoma (POAG) were enrolled. Each enrolled patient underwent a thorough ophthalmological examination including the Humphrey visual field test and measurement of FMD via high-resolution 2-dimensional ultrasonographic imaging of the brachial artery. Blood samples were evaluated for biochemistry and lipid profiles as well as levels of high-sensitivity C-reactive protein (hsCRP). The annual change of threshold sensitivity of the visual field in each test location were analyzed with pointwise linear regression. The correlation between long-term visual field progression and FMD was evaluated.A mean follow-up of 7.47 ± 1.84 years revealed a faster progression rate over the superior visual field in all 40 OAG patients (superior field -0.24 ± 0.67 dB/y, inferior field -0.10 ± 0.59 dB/y, P = 0.37). However, only the annual sensitivity change of the inferior peripheral field showed correlation with baseline FMD. There was no significant difference in the change slope of visual field between NTG and POAG patients.A correlation between baseline brachial artery FMD and visual field progression was observed in the inferior peripheral field in patients with NTG and POAG. This result suggests that peripheral vascular endothelial dysfunction may be related to glaucoma progression. PMID:26962832

  3. Effects of real and simulated weightlessness on the cardiac and peripheral vascular functions of humans: A review.

    PubMed

    Zhu, Hui; Wang, Hanqing; Liu, Zhiqiang

    2015-01-01

    Weightlessness is an extreme environment that can cause a series of adaptive changes in the human body. Findings from real and simulated weightlessness indicate altered cardiovascular functions, such as reduction in left ventricular (LV) mass, cardiac arrhythmia, reduced vascular tone and so on. These alterations induced by weightlessness are detrimental to the health, safety and working performance of the astronauts, therefore it is important to study the effects of weightlessness on the cardiovascular functions of humans. The cardiovascular functional alterations caused by weightlessness (including long-term spaceflight and simulated weightlessness) are briefly reviewed in terms of the cardiac and peripheral vascular functions. The alterations include: changes of shape and mass of the heart; cardiac function alterations; the cardiac arrhythmia; lower body vascular regulation and upper body vascular regulation. A series of conclusions are reported, some of which are analyzed, and a few potential directions are presented. PMID:26224491

  4. Peripheral artery disease is associated with severe impairment of vascular function.

    PubMed

    Kiani, Soroosh; Aasen, Jonathan G; Holbrook, Monika; Khemka, Abhishek; Sharmeen, Farhana; LeLeiko, Rebecca M; Tabit, Corey E; Farber, Alik; Eberhardt, Robert T; Gokce, Noyan; Vita, Joseph A; Hamburg, Naomi M

    2013-04-01

    Patients with peripheral artery disease (PAD) have higher cardiovascular event rates than patients with established coronary artery disease (CAD) and abnormal endothelial function predicts cardiovascular risk in PAD and CAD. We investigated the hypothesis that PAD is associated with a greater degree of impairment in vascular function than CAD. We used several non-invasive tests to evaluate endothelial function in 1320 men and women with combined PAD and CAD (n = 198), PAD alone (n = 179), CAD alone (n = 466), or controls aged > 45 years without CAD or PAD (n = 477). Patients with PAD had lower brachial artery flow-mediated dilation (5.1 ± 3.9% PAD and CAD, 5.9 ± 4.4% PAD alone) compared to patients with CAD alone (7.0 ± 4.5%) and no PAD or CAD (8.1 ± 5.1%, p < 0.0001). In multivariable models adjusting for clinical covariates and the presence of CAD, PAD remained associated with lower flow-mediated dilation (p < 0.0001). PAD was associated also with lower nitroglycerin-mediated dilation and reactive hyperemia. Patients with both PAD and CAD had a lower digital pulse amplitude tonometry (PAT) ratio in unadjusted models but not in adjusted models. Flow-mediated dilation was modestly associated with PAT ratio in patients with atherosclerotic disease (r = 0.23, p < 0.0001) but not among control participants (r = 0.008, p = 0.93). Our findings indicate that patients with PAD have greater impairment of vasodilator function and are consistent with the possibility that endothelial dysfunction may contribute to adverse cardiovascular prognosis in PAD. PMID:23509089

  5. Peripheral artery disease is associated with severe impairment of vascular function

    PubMed Central

    Kiani, Soroosh; Aasen, Jonathan G; Holbrook, Monika; Khemka, Abhishek; Sharmeen, Farhana; LeLeiko, Rebecca M; Tabit, Corey E; Farber, Alik; Eberhardt, Robert T; Gokce, Noyan; Vita, Joseph A; Hamburg, Naomi M

    2013-01-01

    Patients with peripheral artery disease (PAD) have higher cardiovascular event rates than patients with established coronary artery disease (CAD) and abnormal endothelial function predicts cardiovascular risk in PAD and CAD. We investigated the hypothesis that PAD is associated with a greater degree of impairment in vascular function than CAD. We used several non-invasive tests to evaluate endothelial function in 1320 men and women with combined PAD and CAD (n = 198), PAD alone (n = 179), CAD alone (n = 466), or controls aged > 45 years without CAD or PAD (n = 477). Patients with PAD had lower brachial artery flow-mediated dilation (5.1 ± 3.9% PAD and CAD, 5.9 ± 4.4% PAD alone) compared to patients with CAD alone (7.0 ± 4.5%) and no PAD or CAD (8.1 ± 5.1%, p < 0.0001). In multivariable models adjusting for clinical covariates and the presence of CAD, PAD remained associated with lower flow-mediated dilation (p < 0.0001). PAD was associated also with lower nitroglycerin-mediated dilation and reactive hyperemia. Patients with both PAD and CAD had a lower digital pulse amplitude tonometry (PAT) ratio in unadjusted models but not in adjusted models. Flow-mediated dilation was modestly associated with PAT ratio in patients with atherosclerotic disease (r = 0.23, p < 0.0001) but not among control participants (r = 0.008, p = 0.93). Our findings indicate that patients with PAD have greater impairment of vasodilator function and are consistent with the possibility that endothelial dysfunction may contribute to adverse cardiovascular prognosis in PAD. PMID:23509089

  6. Peripheral Vascular Disease

    MedlinePlus

    ... Information Center Back to previous page En español Aneurysms and Dissections Angina Arrhythmia Bundle Branch Block Cardiomyopathy ... blockage including peripheral artery disease or PAD Aortic aneurysms Buerger's Disease Raynaud's Phenomenon Disease of the veins ...

  7. Pretreatment imaging of peripheral vascular malformations

    PubMed Central

    Johnson, Joshua B; Cogswell, Petrice M; McKusick, Michael A; Binkovitz, Larry A; Riederer, Stephen J; Young, Phillip M

    2015-01-01

    Peripheral vascular malformations (VMs) are complex and diverse vascular lesions which require individualized pretreatment planning. Pretreatment imaging using various modalities, especially magnetic resonance imaging and time-resolved magnetic resonance angiography, is a valuable tool for classifying peripheral VMs to allow proper diagnosis, demonstrate complete extent, identify the nidus, and distinguish between low-flow and high-flow dynamics that determines the treatment approach. We discuss pretreatment imaging findings in four patients with peripheral VMs and how diagnostic imaging helped guide management. PMID:25625123

  8. Fingolimod-Associated Peripheral Vascular Adverse Effects.

    PubMed

    Russo, Margherita; Guarneri, Claudio; Mazzon, Emanuela; Sessa, Edoardo; Bramanti, Placido; Calabrò, Rocco Salvatore

    2015-10-01

    Fingolimod is the first oral disease-modifying drug approved for the treatment of multiple sclerosis. The drug is usually well tolerated, and common adverse effects include bradycardia, headache, influenza, diarrhea, back pain, increased liver enzyme levels, and cough. Fingolimod is thought to provide therapeutic benefit by preventing normal lymphocyte egress from lymphoid tissues, thus reducing the infiltration of autoaggressive lymphocytes into the central nervous system. However, because the drug acts on different sphingosine-1-phosphate receptors, it may induce several biological effects by influencing endothelial cell-cell adhesion, angiogenesis, vascular development, and cardiovascular function. We describe a patient with multiple sclerosis who, after 3 weeks of fingolimod administration, developed purplish blotches over the dorsal surface of the distal phalanges of the second and fifth digits and the middle phalanx of the fourth ray, itching, and edema on his left hand, without other evident clinical manifestations. When fingolimod therapy was discontinued, the clinical picture regressed within a few days but reappeared after a rechallenge test. Physicians should be aware of unexpected peripheral vascular adverse effects due to fingolimod use, and patients with vascular-based acropathies should be carefully screened and monitored when taking this drug. PMID:26349949

  9. Peripheral vascular imaging and intervention

    SciTech Connect

    Kim, D. ); Orron, D.E. )

    1990-01-01

    This reference addresses the entire clinical approach to the vascular system from the diagnosis of pathology to surgery or interventional radiological management. All diagnostic imaging modalities currently available are included with specific information on how to interpret various results. It features discussions of the latest therapeutic techniques, including laser angioplasty, intravascular stents, and transluminal embolization.

  10. Antithrombotic Therapy After Peripheral Vascular Intervention.

    PubMed

    Hu, Peter; Jones, Schuyler

    2016-03-01

    Cardioprotective medications and risk-factor modification are the hallmarks of treatment for all patients with peripheral artery disease (PAD). If symptoms are life-limiting and/or do not respond to conservative treatment, endovascular or surgical revascularization can be considered especially for patients with critical limb ischemia or acute limb ischemia. The rates of peripheral vascular intervention (PVI) have risen dramatically over the past few decades and much of this care have shifted from inpatient hospital settings to outpatient settings and office-based clinics. While PVI rates have surged and technology advancements have dramatically changed the face of PVI, the data behind optimal antithrombotic therapy following PVI is scant. Currently in the USA, most patients are treated with indefinite aspirin therapy and a variable duration of clopidogrel (or other P2Y12 inhibitor)-typically 1 month, 3 months, or indefinite therapy. More observational analyses and randomized clinical trials evaluating clinically relevant outcomes such as cardiovascular morbidity/mortality and the risk of bleeding are needed to guide the optimal role and duration of antithrombotic therapy post-PVI. PMID:26841788

  11. Step‐Monitored Home Exercise Improves Ambulation, Vascular Function, and Inflammation in Symptomatic Patients With Peripheral Artery Disease: A Randomized Controlled Trial

    PubMed Central

    Gardner, Andrew W.; Parker, Donald E.; Montgomery, Polly S.; Blevins, Steve M.

    2014-01-01

    Background This prospective, randomized, controlled clinical trial compared changes in primary outcome measures of claudication onset time (COT) and peak walking time (PWT), and secondary outcomes of submaximal exercise performance, daily ambulatory activity, vascular function, inflammation, and calf muscle hemoglobin oxygen saturation (StO2) in patients with symptomatic peripheral artery disease (PAD) following new exercise training using a step watch (NEXT Step) home‐exercise program, a supervised exercise program, and an attention‐control group. Methods and Results One hundred eighty patients were randomized. The NEXT Step program and the supervised exercise program consisted of intermittent walking to mild‐to‐moderate claudication pain for 12 weeks, whereas the controls performed light resistance training. Change scores for COT (P<0.001), PWT (P<0.001), 6‐minute walk distance (P=0.028), daily average cadence (P=0.011), time to minimum calf muscle StO2 during exercise (P=0.025), large‐artery elasticity index (LAEI) (P=0.012), and high‐sensitivity C‐reactive protein (hsCRP) (P=0.041) were significantly different among the 3 groups. Both the NEXT Step home program and the supervised exercise program demonstrated a significant increase from baseline in COT, PWT, 6‐minute walk distance, daily average cadence, and time to minimum calf StO2. Only the NEXT Step home group had improvements from baseline in LAEI, and hsCRP (P<0.05). Conclusions NEXT Step home exercise utilizing minimal staff supervision has low attrition, high adherence, and is efficacious in improving COT and PWT, as well as secondary outcomes of submaximal exercise performance, daily ambulatory activity, vascular function, inflammation, and calf muscle StO2 in symptomatic patients with PAD. Clinical Trial Registration URL: ClinicalTrials.gov. Unique Identifier: NCT00618670. PMID:25237048

  12. Systemic sclerosis induces pronounced peripheral vascular dysfunction characterized by blunted peripheral vasoreactivity and endothelial dysfunction.

    PubMed

    Frech, Tracy; Walker, Ashley E; Barrett-O'Keefe, Zachary; Hopkins, Paul N; Richardson, Russell S; Wray, D Walter; Donato, Anthony J

    2015-05-01

    Systemic sclerosis (SSc) vasculopathy can result in a digital ulcer (DU) and/or pulmonary arterial hypertension (PAH). We hypothesized that bedside brachial artery flow-mediated dilation (FMD) testing with duplex ultrasound could be used in SSc patients to identify features of patients at risk for DU or PAH. Thirty-eight SSc patients were compared to 52 age-matched healthy controls from the VAMC Utah Vascular Research Laboratory. Peripheral hemodynamics, arterial structure, and endothelial function were assessed by duplex ultrasound. A blood pressure cuff was applied to the forearm and 5-min ischemia was induced. Post-occlusion, brachial artery vascular reactivity (peak hyperemia/area under the curve [AUC]), shear rate, and endothelial function (FMD) were measured. SSc patients had smaller brachial artery diameters (p < 0.001) and less reactive hyperemia (p < 0.001), peak shear rate (p = 0.03), and brachial artery FMD (p < 0.001) compared with healthy controls. Brachial artery FMD was lower (p < 0.05) in SSc patients with DU. Tertile analysis suggested the 2 lower FMD tertiles (<5.40 %) had a 40-50 % chance of presenting with DU while the SSc patients with highest FMD tertile (>5.40 %) had less than 15 % chance of DU. All brachial artery FMD measurements were similar between SSc patients with and without PAH (all p > 0.05). Compared to healthy controls, SSc patients had significantly smaller brachial artery diameter and blunted peripheral vascular reactivity and endothelial function. SSc patients with DU have even greater impairments in endothelial function compared to those without DU. FMD testing has clinical utility to identify SSc patients at risk for DU. PMID:25511849

  13. [Thinking and Problems of Peripheral Vascular Disease Research].

    PubMed

    Shang De-jun

    2016-01-01

    It is necessary to study further syndrome differentiation based treatment of peripheral vascular disease. In order to improve the clinical effect and reduce the rate of amputation, early diagnosis and early intervention are important. Meanwhile, treatment of Chinese medicine should be combined with necessary surgical intervention. It should be important to supplement some details about blood stasis syndrome and activating blood and dissolving stasis therapy of peripheral vascular disease. The application of various Chinese medicine external therapies should not be ignored, especially promoting granulation and wound healing therapy. PMID:26955670

  14. The utility of digital subtraction arteriography in peripheral vascular disease.

    PubMed

    Kubal, W S; Crummy, A B; Turnipseed, W D

    1983-01-01

    Digital subtraction angiography (DSA), whether used in conjunction with intravenous or intraarterial injection techniques, has an established role in evaluation of peripheral vascular disease. Use of DSA can reduce the time, cost, and patient discomfort of the standard arteriographic study. While it is limited by field size and patient cooperation in some instances, the utility of noninvasive imaging using intravenous DSA and the added anatomic detail of intraarterial DSA for roadmapping and delineation of small distal vessels provide the basis for future integration of standard arteriographic and DSA methods in assessment of peripheral vascular disease. PMID:6228296

  15. Image-Based Evaluation of Vascular Function and Hemodynamics

    PubMed Central

    Lee, Jongmin

    2013-01-01

    The noticeable characteristics of the blood vascular structure are the inconsistent viscosity of blood and the stiffness of the vascular wall. If we can control these two factors, we can solve more problems related to hemodynamics and vascular wall function. Understanding the properties of hemodynamics and vascular wall function may provide more information applicable to clinical practice for cardiovascular disease. The bedside techniques evaluating vascular function usually measure indirect parameters. In contrast, some medical imaging techniques provide clear and direct depictions of functional cardiovascular characteristics. In this review, image-based evaluation of hemodynamic and vascular wall functions is discussed from the perspective of blood flow velocity, flow volume, flow pattern, peripheral vascular resistance, intraluminal pressure, vascular wall stress, and wall stiffness. PMID:26587430

  16. Infrared thermal imaging for detection of peripheral vascular disorders

    PubMed Central

    Bagavathiappan, S.; Saravanan, T.; Philip, John; Jayakumar, T.; Raj, Baldev; Karunanithi, R.; Panicker, T. M. R.; Korath, M. Paul; Jagadeesan, K.

    2009-01-01

    Body temperature is a very useful parameter for diagnosing diseases. There is a definite correlation between body temperature and diseases. We have used Infrared Thermography to study noninvasive diagnosis of peripheral vascular diseases. Temperature gradients are observed in the affected regions of patients with vascular disorders, which indicate abnormal blood flow in the affected region. Thermal imaging results are well correlated with the clinical findings. Certain areas on the affected limbs show increased temperature profiles, probably due to inflammation and underlying venous flow changes. In general the temperature contrast in the affected regions is about 0.7 to 1° C above the normal regions, due to sluggish blood circulation. The results suggest that the thermal imaging technique is an effective technique for detecting small temperature changes in the human body due to vascular disorders. PMID:20126565

  17. Peripheral vascular responses to fluorocarbon administration.

    PubMed

    Faithfull, N S; King, C E; Cain, S M

    1987-03-01

    To detect the local effect of hyperoxia on skeletal muscle vasculature, 2.5-ml boluses of oxygenated or deoxygenated fluorocarbon emulsion (F-O2 or F-N2) were washed through the hindlimb of anesthetized dogs at prevailing arterial pressure. Instantaneous hematocrit changes at the outflow were registered and stored in digital form with the red cells serving as the nondiffusible tracer in the resulting washout curves. A gamma density function was fitted and the gamma index (1/square root of alpha) was derived as a measure of skewness or perfusion heterogeneity. After recovery from the initial hypotensive reaction to fluorocarbon emulsion, washout curves for F-O2 and F-N2 were registered and blood samples were taken during 40 min of normoxia followed by 40 min of hypoxic hypoxia. The initial reaction to fluorocarbon significantly increased the gamma index so that the experiments began with a high index of perfusion heterogeneity in the limb vasculature. No significant difference was seen between F-O2 and F-N2 in normoxia but F-O2 maintained greater heterogeneity during hypoxia. The increased heterogeneity observed after the fluorocarbon reaction correlated highly with the severity of the hypotensive reaction which was also found to correlate inversely with the ability of the limb musculature to increase the O2 extraction ratio with onset of hypoxia. This blunting of microcirculatory reactivity to hyperoxia and hypoxia was attributed, in part, to the initial transient fluorocarbon reaction, possibly mediated by complement activation. PMID:3587075

  18. Effect of Artificial Nerve Conduit Vascularization on Peripheral Nerve in a Necrotic Bed

    PubMed Central

    Iijima, Yuki; Murayama, Akira; Takeshita, Katsushi

    2016-01-01

    Background: Several types of artificial nerve conduit have been used for bridging peripheral nerve gaps as an alternative to autologous nerves. However, their efficacy in repairing nerve injuries accompanied by surrounding tissue damage remains unclear. We fabricated a novel nerve conduit vascularized by superficial inferior epigastric (SIE) vessels and evaluated whether it could promote axonal regeneration in a necrotic bed. Methods: A 15-mm nerve conduit was implanted beneath the SIE vessels in the groin of a rat to supply it with blood vessels 2 weeks before nerve reconstruction. We removed a 13-mm segment of the sciatic nerve and then pressed a heated iron against the dorsal thigh muscle to produce a burn. The defects were immediately repaired with an autograft (n = 10), nerve conduit graft (n = 8), or vascularized nerve conduit graft (n = 8). Recovery of motor function was examined for 18 weeks after surgery. The regenerated nerves were electrophysiologically and histologically evaluated. Results: The vascularity of the nerve conduit implanted beneath the SIE vessels was confirmed histologically 2 weeks after implantation. Between 14 and 18 weeks after surgery, motor function of the vascularized conduit group was significantly better than that of the nonvascularized conduit group. Electrophysiological and histological evaluations revealed that although the improvement did not reach the level of reinnervation achieved by an autograft, the vascularized nerve conduit improved axonal regeneration more than did the conduit alone. Conclusion: Vascularization of artificial nerve conduits accelerated peripheral nerve regeneration, but further research is required to improve the quality of nerve regeneration. PMID:27257595

  19. Peripherally Inserted Central Catheters Complicated by Vascular Erosion in Neonates.

    PubMed

    Blackwood, Brian P; Farrow, Kathryn N; Kim, Stan; Hunter, Catherine J

    2016-08-01

    Peripherally inserted central catheters (PICCs) are widely used in the pediatric population, and their use continues to grow in popularity. These catheters provide a reliable source of venous access to neonatal patients but can also be the cause of life-threatening complications. There are several well-documented complications such as infections, catheter thrombosis, vascular extravasations, and fractured catheters. However, the complication of vascular erosion into the pleural space using both small and silicone-based catheters is rarely described. After obtaining institutional review board approval, we identified 4 cases to review of PICCs complicated by vascular erosions in the past 2 years. Herein, we also review the current literature of PICC complications. Getting the catheter tip as close to the atrial-caval junction as possible and confirmation of this placement are of the utmost importance. The thick wall of the vena cava near the atrium seems to be less likely to perforate; in addition, this position provides increased volume and turbulence to help dilute the hyperosmolar fluid, which seems to also be a factor in this complication. A daily screening chest x-ray in patients with upper extremity PICCs and ongoing parenteral nutrition (PN) are not necessary at this time given the overall low rate of vascular erosion and concerns regarding excessive radiation exposure in pediatric populations. However, a low threshold for chest x-ray imaging in patients with even mild respiratory symptoms in the setting of upper extremity PN is recommended. PMID:25700180

  20. Association between Bacterial Infection and Peripheral Vascular Disease: A Review.

    PubMed

    Budzyński, Jacek; Wiśniewska, Joanna; Ciecierski, Marek; Kędzia, Anna

    2016-03-01

    There are an increasing number of data showing a clinically important association between bacterial infection and peripheral artery disease (PAD). Bacteria suspected of being involved in PAD pathogenesis are: periodontal bacteria, gut microbiota, Helicobacter pylori, and Chlamydia pneumoniae. Infectious agents may be involved in the pathogenesis of atherosclerosis via activation of a systemic or local host immunological response to contamination of extravascular tissues or the vascular wall, respectively. A systemic immunological reaction may damage vascular walls in the course of autoimmunological cross-reactions between anti-pathogen antibodies and host vascular antigens (immunological mimicry), pathogen burden mechanisms (nonspecific activation of inflammatory processes in the vascular wall), and neuroendocrine-immune cross-talk. Besides activating the inflammatory pathway, bacterial infection may trigger PAD progression or exacerbation by enhancement of platelet reactivity, by a stimulatory effect on von Willebrand factor binding, factor VIII, fibrinogen, P-selectin activation, disturbances in plasma lipids, increase in oxidative stress, and resistance to insulin. Local inflammatory host reaction and induction of atherosclerotic plaque progression and/or instability result mainly from atherosclerotic plaque colonization by microorganisms. Despite these premises, the role of bacterial infection in PAD pathogenesis should still be recognized as controversial, and randomized, controlled trials are required to evaluate the outcome of periodontal or gut bacteria modification (through diet, prebiotics, and probiotics) or eradication (using antibiotics) in hard and surrogate cardiovascular endpoints. PMID:26900306

  1. Endothelial Outgrowth Cells: Function and Performance in Vascular Grafts

    PubMed Central

    Glynn, Jeremy J.

    2014-01-01

    The clinical need for vascular grafts continues to grow. Tissue engineering strategies have been employed to develop vascular grafts for patients lacking sufficient autologous vessels for grafting. Restoring a functional endothelium on the graft lumen has been shown to greatly improve the long-term patency of small-diameter grafts. However, obtaining an autologous source of endothelial cells for in vitro endothelialization is invasive and often not a viable option. Endothelial outgrowth cells (EOCs), derived from circulating progenitor cells in peripheral blood, provide an alternative cell source for engineering an autologous endothelium. This review aims at highlighting the role of EOCs in the regulation of processes that are central to vascular graft performance. To characterize EOC performance in vascular grafts, this review identifies the characteristics of EOCs, defines functional performance criteria for EOCs in vascular grafts, and summarizes the existing work in developing vascular grafts with EOCs. PMID:24004404

  2. Peripheral Vascular Diagnostic Laboratory Record, Office Accounting and Research System

    PubMed Central

    Lofink, Raymond M.; Wolfson, Sidney K.; Lahoda, Edward J.

    1981-01-01

    A computerized Record, Office Accounting, and Research system (“ROAR”) has been developed for use in the Peripheral Vascular Diagnostic Laboratory of Montefiore Hospital, Pittsburgh, Pennsylvania. The interactive, menu-driven system utilizes an in-office microcomputer for maintaining patient records with a dial-up link to a time-sharing system at the University of Pittsburgh for performing research activities. Formats for internal storage, screen editing, and printed reports are easily specified to permit additions of new forms and upward-compatible versions of old forms. An on-line patient directory and an expandable library of floppy diskettes provide a large capacity of storage for permanent patient records. An interestingly simple, cost-effective, but powerful combination of three processors using commercial and custom-written software is presented.

  3. [Sleep quality in aged patients with peripheral vascular diseases].

    PubMed

    Corrêa, Karina; Ceolim, Maria Filomena

    2008-03-01

    Peripheral vascular diseases (PVD) are prevalent among the elderly, and, due to their chronic character, result in poor quality of life and poor sleep quality. This study aimed at evaluating sleep quality of elderly people diagnosed with PVD who undergo clinical ambulatory treatment in a university hospital in Campinas, in the State of São Paulo. Subjects (n=50, aged 74 +/- 8 years old) answered the Pittsburgh Sleep Quality Index (PSQI) and provided basic demographic data and PVD history (35 subjects had arterial blockage in lower limbs). Results showed that 34 subjects presented bad sleep quality; sleep length was 5.8 (+/- 2.3) hours, and, according to 23 subjects, night sleep was frequently disturbed by pain (thrice a week or more). Eighteen subjects took analgesics; four took sleep medicines. Findings may have important implications for nurses working with PVD patients, stressing the need to take into account consequences of PVD on sleep disturbances when planning their interventions. PMID:18450142

  4. Economic evaluation of drugs in peripheral vascular disease and stroke.

    PubMed

    Drummond, M; Davies, L

    1994-01-01

    Increased pressures on health-care budgets mean that governments require good value for money from the resources devoted to health care. In many countries, measures have been introduced to increase efficiency or to contain health-care costs. These include price controls, limitations on reimbursement of health technologies, budgetary reform in health-care institutions, and the encouragement of competition. Given this changing environment, it is important that drugs and other health technologies be shown to give good value for money. The methods of economic evaluation, such as cost-benefit and cost-effectiveness analysis, can be used to assess the value of drugs and other health technologies. They have been widely applied. The economic evaluation of drugs in peripheral vascular disease and stroke would compare the cost of adding the drug with its benefits. These would include improvements in length and quality of life and the savings in treating vascular events that may be postponed, or lessened in intensity, by effective drug therapy. One study, following a clinical trial of naftidrofuryl in stroke, suggested that there would be significant reductions in costs through reductions in hospital stay if recovery was aided. Further research and a large multicenter trial are under way to confirm these findings. In peripheral artery disease there are no economic data collected alongside clinical trials. It is known, however, that the costs of leg ischemia can be significant. A study in the U.K. found that arterial construction would cost around pounds 7,750 per person (1989 prices) and amputation around pounds 11,000 per person.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7517476

  5. Peripheral vascular effects on auscultatory blood pressure measurement.

    PubMed

    Rabbany, S Y; Drzewiecki, G M; Noordergraaf, A

    1993-01-01

    Experiments were conducted to examine the accuracy of the conventional auscultatory method of blood pressure measurement. The influence of the physiologic state of the vascular system in the forearm distal to the site of Korotkoff sound recording and its impact on the precision of the measured blood pressure is discussed. The peripheral resistance in the arm distal to the cuff was changed noninvasively by heating and cooling effects and by induction of reactive hyperemia. All interventions were preceded by an investigation of their effect on central blood pressure to distinguish local effects from changes in central blood pressure. These interventions were sufficiently moderate to make their effect on central blood pressure, recorded in the other arm, statistically insignificant (i.e., changes in systolic [p < 0.3] and diastolic [p < 0.02]). Nevertheless, such alterations were found to modify the amplitude of the Korotkoff sound, which can manifest itself as an apparent change in arterial blood pressure that is readily discerned by the human ear. The increase in diastolic pressure for the cooling experiments was statistically significant (p < 0.001). Moreover, both measured systolic (p < 0.004) and diastolic (p < 0.001) pressure decreases during the reactive hyperemia experiments were statistically significant. The findings demonstrate that alteration in vascular state generates perplexing changes in blood pressure, hence confirming experimental observations by earlier investigators as well as predictions by our model studies. PMID:8463815

  6. Aging and vascular endothelial function in humans

    PubMed Central

    SEALS, Douglas R.; JABLONSKI, Kristen L.; DONATO, Anthony J.

    2012-01-01

    Advancing age is the major risk factor for the development of CVD (cardiovascular diseases). This is attributable, in part, to the development of vascular endothelial dysfunction, as indicated by reduced peripheral artery EDD (endothelium-dependent dilation) in response to chemical [typically ACh (acetylcholine)] or mechanical (intravascular shear) stimuli. Reduced bioavailability of the endothelium-synthesized dilating molecule NO (nitric oxide) as a result of oxidative stress is the key mechanism mediating reduced EDD with aging. Vascular oxidative stress increases with age as a consequence of greater production of reactive oxygen species (e.g. superoxide) without a compensatory increase in antioxidant defences. Sources of increased superoxide production include up-regulation of the oxidant enzyme NADPH oxidase, uncoupling of the normally NO-producing enzyme, eNOS (endothelial NO synthase) (due to reduced availability of the cofactor tetrahydrobiopterin) and increased mitochondrial synthesis during oxidative phosphorylation. Increased bioactivity of the potent endothelial-derived constricting factor ET-1 (endothelin-1), reduced endothelial production of/responsiveness to dilatory prostaglandins, the development of vascular inflammation, formation of AGEs (advanced glycation end-products), an increased rate of endothelial apoptosis and reduced expression of oestrogen receptor α (in postmenopausal females) also probably contribute to impaired EDD with aging. Several lifestyle and biological factors modulate vascular endothelial function with aging, including regular aerobic exercise, dietary factors (e.g. processed compared with non-processed foods), body weight/fatness, vitamin D status, menopause/oestrogen deficiency and a number of conventional and non-conventional risk factors for CVD. Given the number of older adults now and in the future, more information is needed on effective strategies for the prevention and treatment of vascular endothelial aging. PMID

  7. Pulse oximetry in the evaluation of peripheral vascular disease.

    PubMed

    Jawahar, D; Rachamalla, H R; Rafalowski, A; Ilkhani, R; Bharathan, T; Anandarao, N

    1997-08-01

    The role of pulse oximetry in the evaluation of peripheral vascular disease (PVD) was investigated. In addition, the value of elevating the limb to improve the sensitivity of detection of PVD by the pulse oximeter was also determined. Pulse oximetry reading in the toes were obtained in 40 young, healthy volunteers and in 40 randomly selected patients referred to the vascular investigation laboratory over a period of two months. All 40 healthy volunteers had normal pulse oximetry readings. Normal pulse oximetry reading in the toes was defined as > 95% O2 Sat and +/-2 of finger pulse oximetry reading. In all 40 patients, pulse oximetry readings were either normal or not detected at all. Since there was no gradation in decrease in the pulse oximetry reading with severity of disease or with elevation of the patient's lower extremity, an absent or no reading was considered as an abnormal result from the test. The frequency of abnormal pulse oximetry readings increased significantly in groups with abnormal ankle-brachial pressure index (ABPI) and also varied significantly with elevation of the patients' lower limbs. In patients with no PVD detected by Doppler (ABPI > 0.9), pulse oximetry readings were normal in all. However, in patients with moderate PVD (ABPI, 0.5-0.9), 84% of the patients' lower limbs had normal pulse oximetry readings and 16% had an abnormal reading at baseline level (flat). An additional 12% of the lower limbs in this group had an abnormal reading on elevation of the limb to 12 inches. In patients with severe PVD (ABPI < 0.5), 54% of the patients' lower limbs had an abnormal reading at baseline and an additional 23% had an abnormal reading at elevation of the limb to 12 inches. In conclusion, pulse oximetry was not a sensitive test for detecting early PVD. PMID:9269142

  8. Common Aging Signature in the Peripheral Blood of Vascular Dementia and Alzheimer's Disease.

    PubMed

    Luo, Hongbo; Han, Guangchun; Wang, Jiajia; Zeng, Fan; Li, Yuanming; Shao, Shaoju; Song, Fuhai; Bai, Zhouxian; Peng, Xing; Wang, Yan-Jiang; Shi, Xiangqun; Lei, Hongxing

    2016-08-01

    Alzheimer's disease (AD) and vascular dementia (VaD) are the two most dominant forms of dementia in elderly people. Due to the large overlap between AD and VaD in clinical observations, great controversies exist regarding the distinction and connection between these two types of senile dementia. Here for the first time, we resort to the gene expression pattern of the peripheral blood to compare AD and VaD objectively. In our previous work, we have demonstrated that the dysregulation of gene expression in AD is unique among the examined diseases including neurological diseases, cancer, and metabolic diseases. In this study, we found that the dysregulation of gene expression in AD and VaD is quite similar to each other at both functional and gene levels. Interestingly, the dysregulation started at the early stages of the diseases, namely mild cognitive impairment (MCI) and vascular cognitive impairment (VCI). We have also shown that this signature is distinctive from that of peripheral vascular diseases. Comparison with aging studies revealed that the most profound change in AD and VaD, namely ribosome, is consistent with the accelerated aging scenario. This study may have implications to the common mechanism between AD and VaD. PMID:26099307

  9. [Quality standards for ultrasonographic assessment of peripheral vascular malformations and vascular tumors. Report of the French Society for Vascular Medicine].

    PubMed

    Laroche, J-P; Becker, F; Khau-Van-Kien, A; Baudoin, P; Brisot, D; Buffler, A; Coupé, M; Jurus, C; Mestre, S; Miserey, G; Soulier-Sotto, V; Tissot, A; Viard, A; Vignes, S; Quéré, I

    2013-02-01

    THE QUALITY STANDARDS OF THE FRENCH SOCIETY OF VASCULAR MEDICINE FOR THE ULTRASONOGRAPHIC ASSESSMENT OF VASCULAR MALFORMATIONS ARE BASED ON THE TWO FOLLOWING REQUIREMENTS: Technical know-how: mastering the use of ultrasound devices and the method of examination. Medical know-how: ability to adapt the methods and scope of the examination to its clinical indication and purpose, and to rationally analyze and interpret its results. AIMS OF THE QUALITY STANDARDS: To describe an optimal method of examination in relation to the clinical question and hypothesis. To achieve consistent practice, methods, glossary, and reporting. To provide good practice reference points, and promote a high-quality process. ITEMS OF THE QUALITY STANDARDS: The three levels of examination; their clinical indications and goals. The reference standard examination (level 2), its variants according to clinical needs. The minimal content of the examination report; the letter to the referring physician (synthesis, conclusion and proposal for further investigation and/or therapeutic management). Commented glossary (anatomy, hemodynamics, semiology). Technical bases. Settings and use of ultrasound devices. Here, we discuss the methods of using ultrasonography for the assessment of peripheral vascular malformations and tumors. PMID:23312609

  10. A Case of Polyarteritis Nodosa Presenting Initially as Peripheral Vascular Disease

    PubMed Central

    Parikh, Sameer; Lu, Lee

    2008-01-01

    Polyarteritis nodosa is a rare necrotizing vasculitis that can be progressive and fatal, and its initial presenting symptom may be leg claudication due to peripheral vascular ischemia. To date, there have been fewer than ten case reports of polyarteritis nodosa presenting as peripheral vascular disease. We report a case of a 38-year-old man initially diagnosed to have premature peripheral vascular disease who presented 1 year later with symptoms consistent with giant cell arteritis and subsequently developed bowel ischemia leading to a fatal outcome. Based on the autopsy and the patient’s clinical course, the final diagnosis was polyarteritis nodosa. This case illustrates the challenges in diagnosing polyarteritis nodosa and the importance of considering vasculitis in young patients presenting with atypical presentations of diseases such as peripheral vascular disease or giant cell arteritis. PMID:18560943

  11. Exercise performance and peripheral vascular insufficiency improve with AMPK activation in high-fat diet-fed mice.

    PubMed

    Baltgalvis, Kristen A; White, Kathy; Li, Wei; Claypool, Mark D; Lang, Wayne; Alcantara, Raniel; Singh, Baljit K; Friera, Annabelle M; McLaughlin, John; Hansen, Derek; McCaughey, Kelly; Nguyen, Henry; Smith, Ira J; Godinez, Guillermo; Shaw, Simon J; Goff, Dane; Singh, Rajinder; Markovtsov, Vadim; Sun, Tian-Qiang; Jenkins, Yonchu; Uy, Gerald; Li, Yingwu; Pan, Alison; Gururaja, Tarikere; Lau, David; Park, Gary; Hitoshi, Yasumichi; Payan, Donald G; Kinsella, Todd M

    2014-04-15

    Intermittent claudication is a form of exercise intolerance characterized by muscle pain during walking in patients with peripheral artery disease (PAD). Endothelial cell and muscle dysfunction are thought to be important contributors to the etiology of this disease, but a lack of preclinical models that incorporate these elements and measure exercise performance as a primary end point has slowed progress in finding new treatment options for these patients. We sought to develop an animal model of peripheral vascular insufficiency in which microvascular dysfunction and exercise intolerance were defining features. We further set out to determine if pharmacological activation of 5'-AMP-activated protein kinase (AMPK) might counteract any of these functional deficits. Mice aged on a high-fat diet demonstrate many functional and molecular characteristics of PAD, including the sequential development of peripheral vascular insufficiency, increased muscle fatigability, and progressive exercise intolerance. These changes occur gradually and are associated with alterations in nitric oxide bioavailability. Treatment of animals with an AMPK activator, R118, increased voluntary wheel running activity, decreased muscle fatigability, and prevented the progressive decrease in treadmill exercise capacity. These functional performance benefits were accompanied by improved mitochondrial function, the normalization of perfusion in exercising muscle, increased nitric oxide bioavailability, and decreased circulating levels of the endogenous endothelial nitric oxide synthase inhibitor asymmetric dimethylarginine. These data suggest that aged, obese mice represent a novel model for studying exercise intolerance associated with peripheral vascular insufficiency, and pharmacological activation of AMPK may be a suitable treatment for intermittent claudication associated with PAD. PMID:24561866

  12. Perioperative heparin prophylaxis of deep venous thrombosis in patients with peripheral vascular disease

    SciTech Connect

    Spebar, M.J.; Collins, G.J. Jr.; Rich, N.M.; Kang, I.Y.; Clagett, G.P.; Salander, J.M.

    1981-12-01

    Perioperative low dose heparin was administered to 24 patients who were compared with 19 control patients undergoing peripheral vascular surgical procedures. This prophylactic measure was ineffective in reducing the incidence of subclinical, postoperative deep venous thrombosis, as indicated by iodine-125 fibrinogen scanning. The data suggest that patients undergoing vascular surgery will not benefit from the routine application of this prophylactic regimen.

  13. VEGF gene therapy for coronary artery disease and peripheral vascular disease

    SciTech Connect

    Rasmussen, Henrik Sandvad; Rasmussen, Camilla Sandvad; Macko, Jennifer

    2002-06-01

    Coronary artery disease (CAD) and peripheral arterial disease (PAD) are significant medical problems worldwide. Although substantial progress has been made in prevention as well as in the treatment, particularly of CAD, there are a large number of patients, who despite maximal medical treatment have substantial symptomatology and who are not candidates for mechanical revascularization. Therapeutic angiogenesis represents a novel, conceptually appealing treatment option. Ad{sub GV}VEGF121.10 (BIOBYPASS) is an adenovector, carrying the transgene encoding for human vascular endothelial growth factor 121 (VEGF{sub 121}). A number of preclinical studies have demonstrated angiogenic activity of BIOBYPASS, not only anatomically but also functionally. Phase I clinical studies have demonstrated that intramyocardial infection of BIOBYPASS in patients with severe CAD as well as intramuscular injections of BIOBYPASS in patients with severe peripheral vascular disease (PVD) was well tolerated; furthermore, these studies provided some intriguing indications of activity, which led to initiation of major randomized Phase II 'proof-of-concept' studies. This paper provides a review of the rationale behind BIOBYPASS as well as a summary of pertinent preclinical and early clinical data.

  14. The human peripheral lymph node vascular addressin. An inducible endothelial antigen involved in lymphocyte homing.

    PubMed Central

    Michie, S. A.; Streeter, P. R.; Bolt, P. A.; Butcher, E. C.; Picker, L. J.

    1993-01-01

    The extravasation of blood-borne lymphocytes into organized lymphoid tissues and sites of chronic inflammation is directed in part by interactions of lymphocyte surface adhesion molecules, known as homing receptors, with tissue-selective endothelial ligands called vascular addressins. In mice and humans, lymphocyte L-selectin and the peripheral lymph node addressin (PNAd) form a homing receptor-endothelial ligand pair involved in lymphocyte traffic to peripheral lymph node (PLN). We have examined the tissue distribution and function of human PNAd, using monoclonal antibody MECA-79 and in vitro assays of L-selectin-dependent lymphocyte binding. We demonstrate that PNAd is expressed by human high endothelial venules (HEV) in lymphoid tissues which support lymphocyte adhesion via a PLN-associated recognition system. MECA-79 inhibits adhesion to these HEV of a cell line that binds predominantly via the PLN-homing receptor, L-selectin, but has no effect on adhesion by a mucosal HEV-binding cell line. Furthermore, MECA-79 blocks binding of human peripheral blood mononuclear cells to both PLN and tonsil HEV, but not significantly to HEV in the appendix. In addition, we demonstrate PNAd induction on venules at chronic inflammatory sites in humans, particularly sites with severe or long-standing chronic inflammatory involvement. These results confirm that PNAd functions as a PLN vascular addressin in humans, and that in addition to directing normal lymphocyte recirculation to lymph nodes and tonsils, this addressin likely participates in lymphocyte recruitment to sites of chronic inflammation. Images Figure 1 Figure 4 PMID:8256856

  15. Vascular Function in Alzheimer's Disease and Vascular Dementia.

    PubMed

    Tachibana, Hisatsugu; Washida, Kazuo; Kowa, Hisatomo; Kanda, Fumio; Toda, Tatsushi

    2016-08-01

    We investigated vascular functioning in patients with a clinical and radiological diagnosis of either Alzheimer's disease (AD) or vascular dementia (VaD) and examined a possible relationship between vascular function and cognitive status. Twenty-seven patients with AD, 23 patients with VaD, and 26 healthy control patients underwent measurements of flow-mediated dilation (FMD), ankle-brachial index (ABI), cardioankle vascular index (CAVI), and intima-media thickness (IMT). The FMD was significantly lower in patients with AD or VaD compared to controls. There were no significant differences in ABI, CAVI, or IMT among the 3 groups. A significant correlation was found between Mini-Mental State Examination (MMSE) scores and FMD. Furthermore, a multiple regression analysis revealed that FMD was significantly predicted by MMSE scores. These results suggest that endothelial involvement plays a role in AD pathogenesis, and FMD may be more sensitive than other surrogate methods (ABI, CAVI, and IMT) for detecting early-stage atherosclerosis and/or cognitive decline. PMID:27284205

  16. Exercise testing and training in patients with peripheral vascular disease and lower extremity amputation.

    PubMed

    Priebe, M; Davidoff, G; Lampman, R M

    1991-05-01

    Patients with peripheral vascular disease have a high risk of coronary artery disease. The risk is even greater when the peripheral vascular disease leads to lower extremity amputation. Exercise testing using lower extremity exercise has been the "gold standard" for screening for coronary artery disease, but many patients with peripheral vascular disease and those with amputations have difficulty doing this type of exercise. Arm exercise ergometry has been shown to be a safe and effective alternative for the detection of coronary artery disease in patients who cannot do leg exercise. This test has also been used to determine safe exercise levels and may be able to predict the ultimate level of prosthetic use in amputees. Exercise training with arm ergometry also improves cardiovascular efficiency and upper body strength in poorly conditioned patients. Studies are needed to appreciate fully the role of exercise testing and training in the recovery of these patients after amputation. PMID:1866958

  17. Simultaneous hybrid peripheral re-vascularization: early results.

    PubMed

    Yurekli, Ismail; Gokalp, Orhan; Gunes, Tevfik; Yilik, Levent; Gurbuz, Ali

    2013-10-01

    Endovascular and open surgical interventions may be combined in treatment of peripheral arterial disease. In this study, we presented our simultaneous hybrid peripheral interventions under the light of current literature data. Eleven patients who were operated for occlusive peripheral arterial disease without aneurysms between June 2008 and November 2010 at our hybrid operating room were investigated retrospectively. Generally, endovascular intervention was performed initially, and then followed by surgery. After hybrid interventions, control angiograms were held during the same session. None of the patients experienced either stent or graft occlusion during early postoperative period. Primary patency rate was found to be 100% for the postoperative first six months. Ankle-brachial indices (ABI) increased significantly during postoperative period and clinical symptoms were relieved in all patients (mean preoperative ABI: 0.43 ± 0.08, mean postoperative sixth month ABI: 0.87 ± 0.08). Peripheral hybrid interventions may be performed both in separate sessions and also simultaneously by experienced teams if an angiography device is available within the operating room. PMID:23518846

  18. High Temporal and Spatial Resolution Imaging of Peripheral Vascular Malformations

    PubMed Central

    Mostardi, Petrice M.; Young, Phillip M.; McKusick, Michael A.; Riederer, Stephen J.

    2013-01-01

    Purpose To assess the performance of a recently developed 3D time-resolved CE-MRA technique, Cartesian Acquisition with Projection-Reconstruction-like sampling (CAPR), for accurate characterization and treatment planning of vascular malformations of the periphery. Materials and Methods Twelve patient studies were performed (eight female, four male; average age, 33 years). The protocol consisted of three-dimensional (3D) time-resolved CE-MRA followed by a single late phase T1-weighted acquisition. Vascular malformations were imaged in the forearm, hand, thigh, and foot. Imaging evaluation was performed for accurate characterization of lesion type, identification of feeding and draining vessels, involvement with surrounding tissue, overall quality for diagnosis and treatment planning, and correlation with conventional angiography. Results Time-resolved CE-MRA allowed for characterization of malformation flow and type. Feeding and draining vessels were identified in all cases. Overall quality for diagnosis and treatment planning was 3.58/4.0, and correlation with conventional angiography was scored as 3.89/4.0. Conclusion The CAPR time series has been shown to portray the temporal dynamics and structure of vascular malformations as well as the normal vasculature with high quality. CAPR time-resolved imaging is able to accurately characterize high and low flow lesions, allowing for pretreatment lesion assessment and treatment planning. Delayed imaging is important to capture complete filling of very slow flow vascular malformations. PMID:22674646

  19. Central and peripheral pulmonary vascular resistance: Implications for who should undergo pulmonary thromboendarterectomy.

    PubMed

    Poullis, Mike

    2015-08-01

    Pulmonary thromboendarterectomy remains a technically challenging procedure with variable outcomes with regard to improvement in pulmonary function. Reducing the resistance to flow between the pulmonary valve and the pulmonary capillary bed is the key aim of surgery. The resistance to flow is due to the combination of resistance due to the central clot and distal capillary resistance. We hypothesise that the use of fluid mechanics in combination with modern radiology and electronic circuit theory can potentially predict who should or should not undergo a thromboendarterectomy. Electronic circuit theory of two resistors in series was utilised to demonstrate the concept of a model of a central clot and the peripheral pulmonary capillary bed. A simplified 2D model of the lungs utilising finite element analysis and Poiseuille's law was constructed for proof of principle. Modelling predicts that cardiac output and anatomical obstruction interplay and can have profound effects on the outcomes after thromboendarterectomy. Identical pulmonary artery pressures, due to differing cardiac outputs and identical anatomical obstructions due to thrombus can have very different physiological outcomes with regard to changes in pulmonary artery pressure. Modelling the pulmonary vasculature to determine central and peripheral pulmonary vascular resistance may help in predicting who should undergo pulmonary thromboendarterectomy. Mathematical modelling can potentially predict which patients have haemodynamically significant clots in their pulmonary arteries that thromboendarterectomy may potentially help in the setting of pulmonary capillary disease. PMID:25997984

  20. Exercise performance and peripheral vascular insufficiency improve with AMPK activation in high-fat diet-fed mice

    PubMed Central

    Baltgalvis, Kristen A.; White, Kathy; Li, Wei; Claypool, Mark D.; Lang, Wayne; Alcantara, Raniel; Singh, Baljit K.; Friera, Annabelle M.; McLaughlin, John; Hansen, Derek; McCaughey, Kelly; Nguyen, Henry; Smith, Ira J.; Godinez, Guillermo; Shaw, Simon J.; Goff, Dane; Singh, Rajinder; Markovtsov, Vadim; Sun, Tian-Qiang; Jenkins, Yonchu; Uy, Gerald; Li, Yingwu; Pan, Alison; Gururaja, Tarikere; Lau, David; Park, Gary; Hitoshi, Yasumichi; Payan, Donald G.

    2014-01-01

    Intermittent claudication is a form of exercise intolerance characterized by muscle pain during walking in patients with peripheral artery disease (PAD). Endothelial cell and muscle dysfunction are thought to be important contributors to the etiology of this disease, but a lack of preclinical models that incorporate these elements and measure exercise performance as a primary end point has slowed progress in finding new treatment options for these patients. We sought to develop an animal model of peripheral vascular insufficiency in which microvascular dysfunction and exercise intolerance were defining features. We further set out to determine if pharmacological activation of 5′-AMP-activated protein kinase (AMPK) might counteract any of these functional deficits. Mice aged on a high-fat diet demonstrate many functional and molecular characteristics of PAD, including the sequential development of peripheral vascular insufficiency, increased muscle fatigability, and progressive exercise intolerance. These changes occur gradually and are associated with alterations in nitric oxide bioavailability. Treatment of animals with an AMPK activator, R118, increased voluntary wheel running activity, decreased muscle fatigability, and prevented the progressive decrease in treadmill exercise capacity. These functional performance benefits were accompanied by improved mitochondrial function, the normalization of perfusion in exercising muscle, increased nitric oxide bioavailability, and decreased circulating levels of the endogenous endothelial nitric oxide synthase inhibitor asymmetric dimethylarginine. These data suggest that aged, obese mice represent a novel model for studying exercise intolerance associated with peripheral vascular insufficiency, and pharmacological activation of AMPK may be a suitable treatment for intermittent claudication associated with PAD. PMID:24561866

  1. Peripheral Retinal Vascular Patterns in Patients with Rhegmatogenous Retinal Detachment in Taiwan

    PubMed Central

    Chen, San-Ni; Hwang, Jiunn-Feng; Wu, Wen-Chuan

    2016-01-01

    This is an observational study of fluorescein angiography (FA) in consecutive patients with rhegmatogenous retinal detachment (RRD) in Changhua Christian Hospital to investigate the peripheral retinal vascular patterns in those patients. All patients had their age, sex, axial length (AXL), and refraction status (RF) recorded. According to the findings in FA of the peripheral retina, the eyes were divided into 4 groups: in group 1, there was a ramified pattern of peripheral retinal vasculature with gradual tapering; in group 2, there was an abrupt ending of peripheral vasculature with peripheral non-perfusion; in group 3, there was a curving route of peripheral vasculature forming vascular arcades or anastomosis; and in group 4, the same as in group 3, but with one or more wedge-shaped avascular notches. Comparisons of age, sex, AXL, and RF, association of breaks with lattice degeneration and retinal non-perfusion, surgical procedures utilized, and mean numbers of operations were made among the four groups. Of the 73 eyes studied, there were 13 eyes (17.8%) in group 1, 3 eyes (4.1%) in group 2, 40 eyes (54.8%) in group 3 and 17 eyes (23.3%) in group 4. Significant differences in age, AXL and RF, and association of retinal breaks to non-perfusion were noted among the four groups. Patients in group 1 had older ages, while younger ages were noted in groups 3 and 4. Eyes in group 1 had the shortest average AXL and were least myopic in contrast to the eyes in groups 3 and 4. Association of retinal breaks and retinal non-perfusion was significantly higher in groups 2, 3 and 4 than in group 1. In conclusion, peripheral vascular anomalies are common in cases with RRD. Patients with peripheral non-perfusion tend to be younger, with longer axial length and have the breaks associated with retinal non-perfusion. PMID:26909812

  2. Testosterone and Vascular Function in Aging

    PubMed Central

    Lopes, Rhéure A. M.; Neves, Karla B.; Carneiro, Fernando S.; Tostes, Rita C.

    2012-01-01

    Androgen receptors are widely distributed in several tissues, including vascular endothelial and smooth muscle cells. Through classic cytosolic androgen receptors or membrane receptors, testosterone induces genomic and non-genomic effects, respectively. Testosterone interferes with the vascular function by increasing the production of pro-inflammatory cytokines and arterial thickness. Experimental evidence indicates that sex steroid hormones, such as testosterone modulate the synthesis and bioavailability of NO and, consequently, endothelial function, which is key for a healthy vasculature. Of interest, aging itself is accompanied by endothelial and vascular smooth muscle dysfunction. Aging-associated decline of testosterone levels is accompanied by age-related diseases, such as metabolic and cardiovascular diseases, indicating that very low levels of androgens may contribute to cardiovascular dysfunction observed in these age-related disorders or, in other words, that testosterone may have beneficial effects in the cardiovascular system. However, testosterone seems to play a negative role in the severity of renal disease. In this mini-review, we briefly comment on the interplay between aging and testosterone levels, the vascular actions of testosterone and its implications for vascular aging. Renal effects of testosterone and the use of testosterone to prevent vascular dysfunction in elderly are also addressed. PMID:22514541

  3. [Vascular rehabilitation in patients with peripheral arterial disease].

    PubMed

    de Holanda, Ana; Aubourg, Marion; Dubus-Bausière, Valérie; Eveno, Dominique; Abraham, Pierre

    2013-06-01

    Lower limb peripheral arterial disease (PAD) is a frequent debilitating disease associated with a high morbidity and mortality rate. The benefit of rehabilitation in PAD patients has been largely demonstrated, both for patients that undergo amputation, and for patients with claudication. In these latter patients, rehabilitation programs rely on a variety of additional techniques or tools, among which: stretching, specific muscle proprioception, walking and a variety of other physical activities, exercise or situations adapted to community life, lower limb and respiratory physiotherapy, patient's education, support for smoking cessation and healthy nutrition, social support, etc. Whether rehabilitation is performed in specialised integrated structures or performed on a home-based basis, various clinicians are involved. Despite evidence-based proof of efficacy, rehabilitation of PAD patients with claudication is still under-used. PMID:23669319

  4. One minute oxygen uptake in peripheral ischemic vascular disease.

    PubMed Central

    Auchincloss, J H; Meade, J W; Gilbert, R; Chamberlain, B E

    1980-01-01

    Six males, ages 31-58, with ischemic vascular disease of the lower extremities, underwent treadmill testing with measurement of oxygen uptake at 45-60 seconds of exercise (VO2-45-60) as the test score. Tests were performed at 41, 123 and 164 watts of power against gravity. Depressed values were found in five subjects with aortic, iliac or common femoral disease but normal values in a subject with narrowing of the left superficial femoral artery. Reconstructive surgery resulted in normal values in four subjects retested. In three of these a calculation was made of the increased volume of oxygen uptake during the first minute of exercise associated with postsurgical improvement. The average was 430 ml, a value high enough to suggest increased aerobic metabolism of exercising muscles. PMID:7362287

  5. Increased peripheral vascular disease risk progressively constrains perfusion adaptability in the skeletal muscle microcirculation.

    PubMed

    Frisbee, Jefferson C; Butcher, Joshua T; Frisbee, Stephanie J; Olfert, I Mark; Chantler, Paul D; Tabone, Lawrence E; d'Audiffret, Alexandre C; Shrader, Carl D; Goodwill, Adam G; Stapleton, Phoebe A; Brooks, Steven D; Brock, Robert W; Lombard, Julian H

    2016-02-15

    To determine the impact of progressive elevations in peripheral vascular disease (PVD) risk on microvascular function, we utilized eight rat models spanning "healthy" to "high PVD risk" and used a multiscale approach to interrogate microvascular function and outcomes: healthy: Sprague-Dawley rats (SDR) and lean Zucker rats (LZR); mild risk: SDR on high-salt diet (HSD) and SDR on high-fructose diet (HFD); moderate risk: reduced renal mass-hypertensive rats (RRM) and spontaneously hypertensive rats (SHR); high risk: obese Zucker rats (OZR) and Dahl salt-sensitive rats (DSS). Vascular reactivity and biochemical analyses demonstrated that even mild elevations in PVD risk severely attenuated nitric oxide (NO) bioavailability and caused progressive shifts in arachidonic acid metabolism, increasing thromboxane A2 levels. With the introduction of hypertension, arteriolar myogenic activation and adrenergic constriction were increased. However, while functional hyperemia and fatigue resistance of in situ skeletal muscle were not impacted with mild or moderate PVD risk, blood oxygen handling suggested an increasingly heterogeneous perfusion within resting and contracting skeletal muscle. Analysis of in situ networks demonstrated an increasingly stable and heterogeneous distribution of perfusion at arteriolar bifurcations with elevated PVD risk, a phenomenon that was manifested first in the distal microcirculation and evolved proximally with increasing risk. The increased perfusion distribution heterogeneity and loss of flexibility throughout the microvascular network, the result of the combined effects on NO bioavailability, arachidonic acid metabolism, myogenic activation, and adrenergic constriction, may represent the most accurate predictor of the skeletal muscle microvasculopathy and poor health outcomes associated with chronic elevations in PVD risk. PMID:26702145

  6. Association between abdominal aortic diameter and peripheral vascular disease.

    PubMed

    Rajkumar, C; Bonapace, S; Starr, J; Radia, M; Bulpitt, C J

    1997-09-01

    Fifty-four elderly people 81.2 years +/- 7.4 (mean age +/- s.d., range 66-98 years) were selected. These included 20 men (78.6 +/- 6.4 years, range 70-91 years) and 34 women (82.2 +/- 7.6 years, range 66-98 years). The relationship between the size of the abdominal aorta and various cardiovascular risk indicators such as calf:-brachial systolic pressure ratio, plasma cholesterol, triglycerides, and random blood glucose were examined. Abdominal aortic diameter correlated well with calf:-brachial systolic ratio measured by Doppler method over the posterior tibial artery and taking the lowest result of the right and left side (r = -0.28, P = 0.04). This correlation tended to be stronger in men (r = -0.55, P = 0.02) compared to women (r = -0.10, P = 0.57). However, the relationship tended to be confined to the systolic pressure in the left leg, raising the hypothesis that left-sided vascular disease is better related to aortic diameter, possibly due to a difference in the effects of reflected waves between the two sides. This needs further investigation. The contrast between the sexes was seen in the absence of any significant difference in resting blood pressure and calf:brachial systolic pressure ratio between the two. This finding suggests that the sex differences in the relationship between the size of the abdominal aorta and calf:brachial systolic pressure ratio are related to intrinsic properties of the arterial wall. PMID:9364278

  7. Buflomedil. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in peripheral and cerebral vascular diseases.

    PubMed

    Clissold, S P; Lynch, S; Sorkin, E M

    1987-05-01

    Buflomedil hydrochloride is a vasoactive drug with a variety of pharmacodynamic properties. Importantly, it seems to improve nutritional blood flow in ischaemic tissue of patients with peripheral and/or cerebral vascular disease by a combination of pharmacological effects: inhibition of alpha-adrenoceptors, inhibition of platelet aggregation, improved erythrocyte deformability, nonspecific and weak calcium antagonistic effects, and oxygen sparing activity. Therapeutic trials with buflomedil in patients with peripheral vascular diseases have shown that it increases walking distances in those with intermittent claudication and heals trophic lesions and reduces rest pain in many patients with more severe vasculopathies. In open clinical trials a good to very good clinical response was achieved in 57 to 87% of those treated. In comparative studies buflomedil 600 mg/day orally was shown to be significantly superior to placebo and comparable in efficacy to pentoxifylline (oxpentifylline) and naftidrofuryl. In patients with symptoms presumed to be due to cerebrovascular insufficiencies and elderly patients with senile dementia, buflomedil 450 to 600 mg/day alleviated symptoms associated with impairment of cognitive and psychometric function and was significantly superior to placebo and slightly more effective than drugs such as cinnarizine, flunarizine and co-dergocrine mesylate. Overall, buflomedil at dosages of up to 600 mg/day has been very well tolerated and discontinuation of therapy has rarely been necessary. Thus, buflomedil would seem to be a useful adjunct to conservative treatment in patients with mild-to-moderate peripheral vascular disease and/or cerebrovascular insufficiency, and well worth a try in patients with more severe peripheral disease unable to undergo surgery. However, a few well-designed long term studies are needed to fully define its overall place in therapy. PMID:3297620

  8. Optical coherence tomography and hyperspectral imaging of vascular recovery in a model of peripheral arterial disease

    NASA Astrophysics Data System (ADS)

    Poole, Kristin M.; Sit, Wesley W.; Tucker-Schwartz, Jason M.; Duvall, Craig L.; Skala, Melissa C.

    2013-03-01

    Peripheral arterial disease (PAD) leads to an increased risk of myocardial infarction and stroke, increased mortality, and reduced quality of life. The mouse hind limb ischemia (HLI) model is the most commonly used system for studying the mechanisms of collateral vessel formation and for testing new PAD therapies, but there is a lack of techniques for acquiring physiologically-relevant, quantitative data intravitally in this model. In this work, non-invasive, quantitative optical imaging techniques were applied to the mouse HLI model over a time course. Optical coherence tomography (OCT) imaged changes in blood flow (Doppler OCT) and microvessel morphology (speckle variance OCT) through the skin of haired mice with high resolution. Hyperspectral imaging was also used to quantify blood oxygenation. In ischemic limbs, blood oxygenation in the footpad was substantially reduced after induction of ischemia followed by complete recovery by three weeks, consistent with standard measures. Three dimensional images of the vasculature distal to vessel occlusion acquired with speckle variance OCT revealed changes in OCT flow signal and vessel morphology. Taken together, OCT and hyperspectral imaging enable intravital acquisition of both functional and morphological data which fill critical gaps in understanding structure-function relationships that contribute to recovery in the mouse HLI model. Therefore, these optical imaging methods hold promise as tools for studying the mechanisms of vascular recovery and evaluating novel therapeutic treatments in preclinical studies.

  9. Microvascular perfusion heterogeneity contributes to peripheral vascular disease in metabolic syndrome.

    PubMed

    Frisbee, Jefferson C; Goodwill, Adam G; Frisbee, Stephanie J; Butcher, Joshua T; Wu, Fan; Chantler, Paul D

    2016-04-15

    A major challenge facing public health is the increased incidence and prevalence of the metabolic syndrome, a clinical condition characterized by excess adiposity, impaired glycaemic control, dyslipidaemia and moderate hypertension. The greatest concern for this syndrome is the profound increase in risk for development of peripheral vascular disease (PVD) in afflicted persons. However, ongoing studies suggest that reductions in bulk blood flow to skeletal muscle may not be the primary contributor to the premature muscle fatigue that is a hallmark of PVD. Compelling evidence has been provided suggesting that an increasingly spatially heterogeneous and temporally stable distribution of blood flow at successive arteriolar bifurcations in metabolic syndrome creates an environment where a large number of the pre-capillary arterioles have low perfusion, low haematocrit, and are increasingly confined to this state, with limited ability to adapt perfusion in response to a challenged environment. Single pharmacological interventions are unable to significantly restore function owing to a divergence in their spatial effectiveness, although combined therapeutic approaches to correct adrenergic dysfunction, elevated oxidant stress and increased thromboxane A2 improve perfusion-based outcomes. Integrated, multi-target therapeutic interventions designed to restore healthy network function and flexibility may provide for superior outcomes in subjects with metabolic syndrome-associated PVD. PMID:25384789

  10. Vascular Imaging: The Evolving Role of the Multidisciplinary Team Meeting in Peripheral Vascular Disease

    PubMed Central

    Christie, Andrew; Roditi, Giles

    2014-01-01

    This article reviews the importance of preinterventional cross-sectional imaging in the evaluation of peripheral arterial disease, as well as discussing the pros and cons of each imaging modality. The importance of a multidisciplinary team approach is emphasized. PMID:25435657

  11. US-guided peripheral vascular interventions, comments on the EFSUMB guidelines.

    PubMed

    Dietrich, Christoph Frank Frank; Horn, Rudolf; Morf, Susanne; Chiorean, Liliana; Dong, Yi; Cui, Xin Wu; Atkinson, Nathan; Jenssen, Christian

    2016-06-01

    Peripheral venous as well as arterial punctures have traditionally been performed on the basis of designated anatomical landmarks. However, due to patients' individual anatomy and vessel pathology and depending on individual operators' skill, this landmark approach is associated with a significant failure rate and complication risk. This review comments on the evidence-based recommendations on ultrasound (US)-guided vascular access which have been published recently within the framework of Guidelines on Interventional Ultrasound (INVUS) of the European Federation of Societies for US in Medicine and Biology (EFSUMB) from a clinical practice point of view. Part 1 of the review had its focus on general aspects of US- guidance and on central venous access, whereas part 2 refers to peripheral vascular access. PMID:27239660

  12. Acute Changes in Peripheral Vascular Tonus and Systemic Circulation during Static Stretching.

    PubMed

    Inami, Takayuki; Baba, Reizo; Nakagaki, Akemi; Shimizu, Takuya

    2015-01-01

    This study aimed to investigate the acute effect of static stretching (SS) on peripheral vascular tonus and to clarify the effect of SS on systemic circulation. Twenty healthy young male volunteers performed a 1-min SS motion of the right triceps surae muscle, repeated five times. The peripheral vascular tonus (|d/a| ratio) was obtained using second derivatives of the photoplethysmogram readings before, during, and after SS. Heart rate and blood pressure (BP) were also measured. The |d/a| ratio and BP were transiently, but significantly, elevated during SS and returned to baseline immediately after SS. Furthermore, we observed a significant correlation between the amount of change in the |d/a| ratio and the ankle range of motion during SS (r = 0.793 to 0.832, P = 0.01). These responses may be caused by mechanical stress during SS. PMID:25833293

  13. Diacylglycerol Kinase Inhibition and Vascular Function.

    PubMed

    Choi, Hyehun; Allahdadi, Kyan J; Tostes, Rita C A; Webb, R Clinton

    2009-01-01

    Diacylglycerol kinases (DGKs), a family of lipid kinases, convert diacylglycerol (DG) to phosphatidic acid (PA). Acting as a second messenger, DG activates protein kinase C (PKC). PA, a signaling lipid, regulates diverse functions involved in physiological responses. Since DGK modulates two lipid second messengers, DG and PA, regulation of DGK could induce related cellular responses. Currently, there are 10 mammalian isoforms of DGK that are categorized into five groups based on their structural features. These diverse isoforms of DGK are considered to activate distinct cellular functions according to extracellular stimuli. Each DGK isoform is thought to play various roles inside the cell, depending on its subcellular localization (nuclear, ER, Golgi complex or cytoplasm). In vascular smooth muscle, vasoconstrictors such as angiotensin II, endothelin-1 and norepinephrine stimulate contraction by increasing inositol trisphosphate (IP(3)), calcium, DG and PKC activity. Inhibition of DGK could increase DG availability and decrease PA levels, as well as alter intracellular responses, including calcium-mediated and PKC-mediated vascular contraction. The purpose of this review is to demonstrate a role of DGK in vascular function. Selective inhibition of DGK isoforms may represent a novel therapeutic approach in vascular dysfunction. PMID:21547002

  14. Poldip2 sustains vascular structure and function

    PubMed Central

    Sutliff, Roy L.; Hilenski, Lula L.; Amanso, Angélica M.; Parastatidis, Ioannis; Dikalova, Anna E.; Hansen, Laura; Datla, Srinivasa Raju; Long, James S.; El-Ali, Alexander M.; Joseph, Giji; Gleason, Rudolph L.; Taylor, W. Robert; Hart, C. Michael; Griendling, Kathy K.; Lassègue, Bernard

    2013-01-01

    Objective Based on previous evidence that polymerase delta interacting protein 2 (Poldip2) increases NADPH oxidase 4 (Nox4) activity in vascular smooth muscle cells (VSMC), we hypothesized that in vivo knockdown of Poldip2 would inhibit reactive oxygen species (ROS) production and alter vascular function. Approach and Results Because homozygous Poldip2 deletion is lethal, Poldip2+/− mice were employed. Poldip2 mRNA and protein levels were reduced by about 50% in Poldip2+/− aorta, with no change in p22phox, Nox1, Nox2 and Nox4 mRNAs. NADPH oxidase activity was also inhibited in Poldip2+/− tissue. Isolated aortas from Poldip2+/− mice demonstrated impaired phenylephrine and potassium chloride-induced contractions, increased stiffness and reduced compliance, associated with disruption of elastic lamellae and excessive extracellular matrix deposition. Collagen I secretion was elevated in cultured VSMC from Poldip2+/− mice and restored by H2O2 supplementation, suggesting that this novel function of Poldip2 is mediated by reactive oxygen species. Furthermore, Poldip2+/− mice were protected against aortic dilatation in a model of experimental aneurysm, an effect consistent with increased collagen secretion. Conclusions Poldip2 knockdown reduces H2O2 production in vivo, leading to increases in extracellular matrix, greater vascular stiffness and impaired agonist-mediated contraction. Thus, unaltered expression of Poldip2 is necessary for vascular integrity and function. PMID:23825363

  15. Endothelial microparticles: Sophisticated vesicles modulating vascular function

    PubMed Central

    Curtis, Anne M; Edelberg, Jay; Jonas, Rebecca; Rogers, Wade T; Moore, Jonni S; Syed, Wajihuddin; Mohler, Emile R

    2015-01-01

    Endothelial microparticles (EMPs) belong to a family of extracellular vesicles that are dynamic, mobile, biological effectors capable of mediating vascular physiology and function. The release of EMPs can impart autocrine and paracrine effects on target cells through surface interaction, cellular fusion, and, possibly, the delivery of intra-vesicular cargo. A greater understanding of the formation, composition, and function of EMPs will broaden our understanding of endothelial communication and may expose new pathways amenable for therapeutic manipulation. PMID:23892447

  16. Perceptions of Canadian vascular surgeons toward pharmacological risk reduction in patients with peripheral arterial disease.

    PubMed

    Al-Omran, Mohammed; Lindsay, Thomas F; Major, Jennifer; Jawas, Ali; Leiter, Larry A; Verma, Subodh

    2006-09-01

    Patients with peripheral arterial disease (PAD) are at a markedly higher risk of cardiovascular morbidity and mortality, with evidence indicating that risk-reduction pharmacotherapy can serve to attenuate cardiovascular events in these patients. Given the central role of vascular surgeons in the treatment of patients with PAD, we sought to determine their perceptions and knowledge of risk-reduction pharmacotherapy in patients with PAD. We conducted a cross-sectional survey of 79 Canadian vascular surgeons who attended the 2004 annual meeting of the Canadian Society for Vascular Surgery, the largest and most representative meeting of its kind in Canada. The recommended targets of low-density lipoprotein cholesterol, blood glucose, and blood pressure were known to 53.8%, 40.4%, and 57.7% of vascular surgeons, respectively. The majority of vascular surgeons (65.4%) reported screening for risk factors in <50% of cases. Although 90.4% of vascular surgeons would recommend antiplatelet therapy for PAD, only 5.8% would recommend angiotensin converting enzyme (ACE) inhibitors and 19.2% would recommend lipid-lowering therapy with statins. Eighty-four percent of Canadian vascular surgeons indicated that their self-assessment of risk reduction in PAD was average to below average, yet 90.4% of them believed that risk-reduction therapy should be recommended or initiated by vascular surgeons. Canadian vascular surgeons' perceptions toward risk reduction in PAD identify knowledge and action gaps, despite the recognition that recommending and instituting therapy is important to patient care. Given the heightened risk of cardiovascular disease in patients with PAD, these data have important implications. PMID:16871436

  17. Comparison of Angioseal and Manual Compression in Patients Undergoing Transfemoral Coronary and Peripheral Vascular Interventional Procedures

    PubMed Central

    Alshehri, Abdullah M.; Elsharawy, Mohamed

    2015-01-01

    Vascular closure devices (VCDs) were introduced in the early 1990s with the goal of limiting the time, labor, bed rest, and patient discomfort associated with manual compression (MC) for hemostasis after cardiovascular interventions. However, its advantage over MC has not been extensively studied after interventional procedures. The aim of this study was to do prospective, randomized study comparing the safety and efficacy of the Angio-Seal (AS) to that of MC in patients undergoing transfemoral coronary and peripheral vascular interventional procedure. A prospective, randomized trial was undertaken on consecutive series of patients admitted to King Fahd Hospital of the University for transfemoral coronary and peripheral vascular interventional procedures over 1 year. The study was designed to compare the hemostasis time in minutes and the incidence of vascular complications in patients receiving AS with those undergoing MC. All patients were on antiplatelets and received heparin during the procedure. During the study period, 160 patients were included, 80 in each group. There was a significant difference in mean time to hemostasis in minutes (15.83 ± 1.63 minutes for MC and 0.42 ± 0.04 minutes for the AS; p < 0.001), time to ambulation in minutes (280 ± 15 for MC and 120 for AS; p = 0.04) and in minor complications (33.8% in MC vs. AS 5%; p < 0.001). However, the major complication rate did not significantly differ between the two groups (0% in AS vs. 2.5% in MC; p = 0.15). AS was found to achieve rapid closure of the femoral access site safely in patients undergoing coronary and peripheral vascular interventional procedures under antiplatelets and systemic heparinization. PMID:26060385

  18. Arm exercise testing with myocardial scintigraphy in asymptomatic patients with peripheral vascular disease

    SciTech Connect

    Goodman, S.; Rubler, S.; Bryk, H.; Sklar, B.; Glasser, L.

    1989-04-01

    Arm exercise with myocardial scintigraphy and oxygen consumption determinations was performed by 33 men with peripheral vascular disease, 40 to 74 years of age (group 2). None had evidence of coronary disease. Nineteen age-matched male control subjects (group 1) were also tested to determine the normal endurance and oxygen consumption during arm exercise in their age group and to compare the results with those obtained during a standard treadmill performance. The maximal heart rate, systolic blood pressure, pressure rate product, and oxygen consumption were all significantly lower for arm than for leg exercise. However, there was good correlation between all these parameters for both types of exertion. The maximal heart rate, work load and oxygen consumption were greater for group 1 subjects than in patients with peripheral vascular disease despite similar activity status. None of the group 1 subjects had abnormal arm exercise ECGs, while six members of group 2 had ST segment changes. Thallium-201 scintigraphy performed in the latter group demonstrated perfusion defects in 25 patients. After nine to 29 months of follow-up, three patients who had abnormal tests developed angina and one of them required coronary bypass surgery. Arm exercise with myocardial scintigraphy may be an effective method of detecting occult ischemia in patients with peripheral vascular disease. Those with good exercise tolerance and no electrocardiographic changes or /sup 201/T1 defects are probably at lower risk for the development of cardiac complications, while those who develop abnormalities at low exercise levels may be candidates for invasive studies.

  19. Peripheral vascular reactivity and serum BDNF responses to aerobic training are impaired by the BDNF Val66Met polymorphism.

    PubMed

    Lemos, José R; Alves, Cleber R; de Souza, Sílvia B C; Marsiglia, Julia D C; Silva, Michelle S M; Pereira, Alexandre C; Teixeira, Antônio L; Vieira, Erica L M; Krieger, José E; Negrão, Carlos E; Alves, Guilherme B; de Oliveira, Edilamar M; Bolani, Wladimir; Dias, Rodrigo G; Trombetta, Ivani C

    2016-02-01

    Besides neuronal plasticity, the neurotrophin brain-derived neurotrophic factor (BDNF) is also important in vascular function. The BDNF has been associated with angiogenesis through its specific receptor tropomyosin-related kinase B (TrkB). Additionally, Val66Met polymorphism decreases activity-induced BDNF. Since BDNF and TrkB are expressed in vascular endothelial cells and aerobic exercise training can increase serum BDNF, this study aimed to test the hypotheses: 1) Serum BDNF levels modulate peripheral blood flow; 2) The Val66Met BDNF polymorphism impairs exercise training-induced vasodilation. We genotyped 304 healthy male volunteers (Val66Val, n = 221; Val66Met, n = 83) who underwent intense aerobic exercise training on a running track three times/wk for 4 mo. We evaluated pre- and post-exercise training serum BDNF and proBDNF concentration, heart rate (HR), mean blood pressure (MBP), forearm blood flow (FBF), and forearm vascular resistance (FVR). In the pre-exercise training, BDNF, proBDNF, BDNF/proBDNF ratio, FBF, and FVR were similar between genotypes. After exercise training, functional capacity (V̇o2 peak) increased and HR decreased similarly in both groups. Val66Val, but not Val66Met, increased BDNF (interaction, P = 0.04) and BDNF/proBDNF ratio (interaction, P < 0.001). Interestingly, FBF (interaction, P = 0.04) and the FVR (interaction, P = 0.01) responses during handgrip exercise (HG) improved in Val66Val compared with Val66Met, even with similar responses of HR and MBP. There were association between BDNF/proBDNF ratio and FBF (r = 0.64, P < 0.001) and FVR (r = -0.58, P < 0.001) during HG exercise. These results show that peripheral vascular reactivity and serum BDNF responses to exercise training are impaired by the BDNF Val66Met polymorphism and such responsiveness is associated with serum BDNF concentrations in healthy subjects. PMID:26603150

  20. Effects of peripheral sympathectomy on thermoregulatory vascular control in the rabbit ear.

    PubMed

    Smith, T L; Koman, L A; Gordon, E S; Holden, M B; Smith, B P

    1998-01-01

    A rabbit ear model of the human digit was utilized to determine the vascular response to peripheral sympathectomy. Vascular responses were evaluated by subjecting chronically instrumented rabbits to a cold stress before and after sympathectomy surgery. The typical response to cold stress is for ear temperatures and auricular cutaneous perfusion to decrease during the cooling phase of the test and to increase toward baseline levels during the rewarming phase after cold exposure. Following peripheral sympathectomy, ear temperatures were significantly increased during both the cooling and rewarming phase of the cold stress test although overall ear perfusion and skin perfusion were not different from sham-operated rabbits. The responses observed in the rabbit ear following peripheral sympathectomy appear to mimic those noted in patients receiving digital peripheral sympathectomies for the treatment of refractory pain and ulceration. Peripheral sympathectomy may result in clinical improvements in patients because it improves both total digital and nutritional cutaneous blood flow. Peripheral sympathectomy in normal rabbit ears does not result in altered perfusion patterns with cold exposure although ear temperature is significantly higher. This pattern of changes suggests that the distribution of extremity perfusion is altered even though overall extremity perfusion and cutaneous perfusion per se are not significantly different from sham-operated controls. Complete sympathectomy was accompanied by a persistent increase in ear temperature and a dissociation between conductance and microvascular perfusion. Auricular conductance was transiently increased and then decreased to levels below preoperative control values. Microvascular perfusion is decreased immediately following amputation/replantation and thereafter increases. PMID:9674929

  1. Exercise training improves vascular mitochondrial function.

    PubMed

    Park, Song-Young; Rossman, Matthew J; Gifford, Jayson R; Bharath, Leena P; Bauersachs, Johann; Richardson, Russell S; Abel, E Dale; Symons, J David; Riehle, Christian

    2016-04-01

    Exercise training is recognized to improve cardiac and skeletal muscle mitochondrial respiratory capacity; however, the impact of chronic exercise on vascular mitochondrial respiratory function is unknown. We hypothesized that exercise training concomitantly increases both vascular mitochondrial respiratory capacity and vascular function. Arteries from both sedentary (SED) and swim-trained (EX, 5 wk) mice were compared in terms of mitochondrial respiratory function, mitochondrial content, markers of mitochondrial biogenesis, redox balance, nitric oxide (NO) signaling, and vessel function. Mitochondrial complex I and complex I + II state 3 respiration and the respiratory control ratio (complex I + II state 3 respiration/complex I state 2 respiration) were greater in vessels from EX relative to SED mice, despite similar levels of arterial citrate synthase activity and mitochondrial DNA content. Furthermore, compared with the SED mice, arteries from EX mice displayed elevated transcript levels of peroxisome proliferative activated receptor-γ coactivator-1α and the downstream targets cytochrome c oxidase subunit IV isoform 1,isocitrate dehydrogenase(Idh)2, and Idh3a, increased manganese superoxide dismutase protein expression, increased endothelial NO synthase phosphorylation (Ser(1177)), and suppressed reactive oxygen species generation (all P< 0.05). Although there were no differences in EX and SED mice concerning endothelium-dependent and endothelium-independent vasorelaxation, phenylephrine-induced vasocontraction was blunted in vessels from EX compared with SED mice, and this effect was normalized by NOS inhibition. These training-induced increases in vascular mitochondrial respiratory capacity and evidence of improved redox balance, which may, at least in part, be attributable to elevated NO bioavailability, have the potential to protect against age- and disease-related challenges to arterial function. PMID:26825520

  2. Influence of vascular function and pulsatile hemodynamics on cardiac function.

    PubMed

    Bell, Vanessa; Mitchell, Gary F

    2015-09-01

    Interactions between cardiac and vascular structure and function normally are optimized to ensure delivery of cardiac output with modest pulsatile hemodynamic overhead. Aortic stiffening with age or disease impairs optimal ventricular-vascular coupling, increases pulsatile load, and contributes to left ventricular (LV) hypertrophy, reduced systolic function, and impaired diastolic relaxation. Aortic pulse pressure and timing of peak systolic pressure are well-known measures of hemodynamic ventricular-vascular interaction. Recent work has elucidated the importance of direct, mechanical coupling between the aorta and the heart. LV systolic contraction results in displacement of aortic and mitral annuli, thereby producing longitudinal stretch in the ascending aorta and left atrium, respectively. Force associated with longitudinal stretch increases systolic load on the LV. However, the resulting energy stored in the elastic elements of the proximal aorta during systole facilitates early diastolic LV recoil and rapid filling. This review discusses current views on hemodynamics and mechanics of ventricular-vascular coupling. PMID:26164466

  3. VASCULAR ACTIONS OF ESTROGENS: FUNCTIONAL IMPLICATIONS

    PubMed Central

    Miller, Virginia M.; Duckles, Sue P.

    2009-01-01

    The impact of estrogen exposure in preventing or treating cardiovascular disease is controversial. But it is clear that estrogen has important effects on vascular physiology and pathophysiology, with potential therapeutic implications. Therefore, it is the goal of this review to summarize, using an integrated approach, current knowledge of the vascular effects of estrogen, both in humans and in experimental animals. Aspects of estrogen synthesis and receptors, as well as general mechanisms of estrogenic action are reviewed with an emphasis on issues particularly relevant to the vascular system. Recent understanding of the impact of estrogen on mitochondrial function suggests that the longer lifespan of women compared to men may depend in part on the ability of estrogen to decrease production of reactive oxygen species in mitochondria. Mechanisms by which estrogen increases endothelial vasodilator function, promotes angiogenesis and modulates autonomic function are summarized. Key aspects of the relevant pathophysiology of inflammation, atherosclerosis, stroke, migraine and thrombosis are reviewed concerning current knowledge of estrogenic effects. A number of emerging concepts are addressed throughout. These include the importance of estrogenic formulation and route of administration and the impact of genetic polymorphisms, either in estrogen receptors or in enzymes responsible for estrogen metabolism, on responsiveness to hormone treatment. The importance of local metabolism of estrogenic precursors and the impact of timing for initiation of treatment and its duration are also considered. While consensus opinions are emphasized, controversial views are presented in order to stimulate future research. PMID:18579753

  4. Prostacyclin synthesis stimulating plasma factor in patients with peripheral vascular disease.

    PubMed

    Strobl-Jäger, E; Fitscha, P; Kaliman, J; Sinzinger, H; Peskar, B A

    1987-08-01

    Human plasma contains a factor capable of stimulating vascular prostacyclin generation even in atherosclerotic vessels with minimal in-vitro capacity for PGI2-synthesis. The activity of this prostacyclin stimulating plasma factor (PSPF) has been reported to be elevated in renal failure and hepatic coma. We are not aware of any data as to whether this PSPF plays a role in maintaining hemostatic balance in patients with peripheral vascular lesions. Therefore, we examined 62 patients with peripheral vascular disease (PVD). This study group was subdivided into normo- and hyperlipemic subjects, patients with and without maturity onset diabetes, and plasma beta-thromboglobulin levels higher and lower than 50 ng/ml. 10 healthy sex and age matched persons served as controls. Vascular prostacyclin formation was studied in vitro after incubation of the patients' plasma and a buffer control with various tissue samples (human femoral artery, rat abdominal and thoracic aorta of healthy and of streptozotocin induced diabetic animals, swine endothelial layer and remaining tissue (media and adventitia) and cultured endothelial (EC) and smooth muscle cells (SMC) of minipig arota. In addition, 6-oxo-PFG1 alpha formation by cultured EC and SMC (minipig aorta source) after incubation with tris HCl-buffer or plasma were estimated by means of specific radioimmunoassays. In general, tissue samples and cells incubated in plasma exhibit a marked increase of in-vitro PGI2-formation as compared to buffer. No difference could be found between PSPF of CHD-patients and healthy controls. Similar findings were obtained using incubated vascular tissue and cultured cells by means of the bioassay and specific RIA, respectively. These findings indicate that the PSPF does not seem to be of any clinical relevance in hemostatic regulation in patients with advanced atherosclerosis. PMID:2958884

  5. Mechanisms of Microgravity Effect on Vascular Function

    NASA Technical Reports Server (NTRS)

    Purdy, Ralph E.

    1995-01-01

    The overall goal of the project is to characterize the effects of simulated microgravity on vascular function. Microgravity is simulated using the hindlimb unweighted (HU) rat, and the following vessels are removed from HU and paired control rats for in vitro analysis: abdominal aorta, carotid and femoral arteries, jugular and femoral veins. These vessels are cut into 3 mm long rings and mounted in tissue baths for the measurement of either isometric contraction, or relaxation of pre- contracted vessels. The isolated mesenteric vascular bed is perfused for the measurement of changes in perfusion pressure as an index of arteriolar constriction or dilation. This report presents, in addition to the statement of the overall goal of the project, a summary list of the specific hypotheses to be tested. These are followed by sections on results, conclusions, significance and plans for the next year.

  6. Treatment of a High-Risk Diabetic Patient with Peripheral Vascular Disease and Osteomyelitis.

    PubMed

    Allen, Latricia L; Kalmar, Garrett; Driver, Vickie R

    2016-06-01

    We report a case of calcaneal osteomyelitis that was surgically resected from a patient with diabetes and peripheral vascular disease. A 91-year-old male with history of type 2 diabetes, peripheral vascular disease, balloon angioplasty, and recent (2 months ago) stent of the superficial femoral artery presented to the emergency department with a left heel wound infection probed to bone. The patient reported having been on intravenous Zosyn for several months via an outside infectious disease provider for clinical suspicion of osteomyelitis, but noted no improvement. This report includes information regarding the clinical examination and imaging findings, which were used to assess this high-risk patient. Our patient underwent a partial calcanectomy and completed a 6-week course of intravenous antibiotics. The purpose of this case report is to illustrate limb preservation in a high-risk patient with compromised vascular supply who underwent a partial calcanectomy for treatment of calcaneal osteomyelitis. The patient underwent surgical resection of the calcaneus without complications and healed unremarkably with the ability to ambulate while wearing an ankle foot orthosis with a custom shoe. This report was authorized for publication as an educational report to contribute to generalizable knowledge and does not include any patient health information. PMID:27423990

  7. Increase in whole-body peripheral vascular resistance during three hours of air or oxygen prebreathing

    NASA Technical Reports Server (NTRS)

    Waligora, J. M.; Horrigan, D. J., Jr.; Conkin, J.; Dierlam, J. J.; Stanford, J., Jr.; Riddle, J. R.

    1984-01-01

    Male and female subjects prebreathed air or 100% oxygen through a mask for 3.0 hours while comfortably reclined. Blood pressures, heart rate, and cardiac output were collected before and after the prebreathe. Peripheral vascular resistance (PVR) was calculated from these parameters and increased by 29% during oxygen prebreathing and 15% during air prebreathing. The oxygen contributed substantially to the increase in PVR. Diastolic blood pressure increased by 18% during the oxygen prebreathe while stystolic blood pressure showed no change under either procedure. The increase in PVR during air prebreathing was attributed to procedural stress common to air and oxygen prebreathing.

  8. Clinical evaluation of a near-infrared tissue spectrometer in peripheral vascular disease

    NASA Astrophysics Data System (ADS)

    Cheng, Xuefeng; Mao, Jian-Min; Xu, Xiaorong; Elmandjra, Mohamed; Bush, Robin; Christenson, Linda; O'Keefe, Bill; Bry, John

    2003-07-01

    We report results of a feasibility clinical evaluation of the near-infrared Photonify Tissue Spectrometer in detection of peripheral vascular disease (PVD). In the evaluation, using a blood pressured cuff, we measure changes in oxygen saturation (StO2) during a temporary occlusion of blood inflow. We use the post-occlusive StO2 recovery rate and the time needed for 80% recovery as parameters to differentiate healthy subjects from subjects with PVD, and obtained high diagnostic accuracy in 19 subjects enrolled in the clinical evaluation. This may suggest that the tissue spectrometer could be useful in diagnosis of PVD.

  9. Catheter Securement Systems for Peripherally Inserted and Nontunneled Central Vascular Access Devices

    PubMed Central

    Krenik, Karen M.; Smith, Graham E.

    2016-01-01

    Sutureless catheter securement systems are intended to eliminate risks associated with sutures. The clinical acceptability of a novel system was investigated compared with the current method of securement for peripherally inserted central catheters (19 facilities using StatLock or sutures) or nontunneled central vascular access devices (3 facilities using StatLock or sutures or HubGuard + Sorbaview Shield). More than 94% of respondents rated the novel system as same, better, or much better than their current product. More than 82% of respondents were willing to replace their current system with the new one. PMID:27379679

  10. Vascular function and ocular involvement in sarcoidosis.

    PubMed

    Siasos, Gerasimos; Paraskevopoulos, Theodoros; Gialafos, Elias; Rapti, Aggeliki; Oikonomou, Evangelos; Zaromitidou, Marina; Mourouzis, Konstantinos; Siasou, Georgia; Gouliopoulos, Nikolaos; Tsalamandris, Sotiris; Vlasis, Konstantinos; Stefanadis, Christodoulos; Papavassiliou, Athanasios G; Tousoulis, Dimitris

    2015-07-01

    Ocular involvement occurs in sarcoidosis (Sar) patients mainly in the form of uveitis. This study was designed to determine if uveitis in Sar patients is associated with vascular impairment. We enrolled 82 Sar patients and 77, age and sex matched, control subjects (Cl). Sar patients were divided into those with ocular sarcoidosis (OS) and those without ocular sarcoidosis (WOS). Endothelial function was evaluated by flow-mediated dilation (FMD). Pulse wave velocity (PWV) was measured as an index of aortic stiffness and augmentation index (AIx) as a measure of arterial wave reflections. Although there was no significant difference in sex, age and mean arterial pressure, patients with OS compared to WOS patients and Cl subjects had impaired FMD (p<0.001), increased AIx (p=0.02) and increased PWV (p=0.001). Interestingly, impaired FMD in Sar patients was independently, from possible covariates (age, sex, smoking habits, arterial hypertension, dyslipidemia), associated with increased odds of ocular involvement (odds ratio=1.69, p=0.001). More precisely ROC curve analysis revealed that FMD had a significant diagnostic ability for the detection of OS (AUC=0.77, p<0.001) with a sensitivity of 79% and a specificity of 68% for an FMD value below 6.00%. To conclude in the present study we have shown that ocular involvement in Sar patients is associated with impaired endothelial function and increased arterial stiffness. These results strengthen the vascular theory which considers uveitis a consequence of vascular dysfunction in Sar patients and reveals a possible clinical importance of the use of endothelial function tests. PMID:25937082

  11. [Complex assessment of vasomotor function of vascular endothelium in patients with hypertension].

    PubMed

    Gel'tser, B I; Savchenko, S V; Kotel'nikov, V N; Plotnikova, I V

    2004-01-01

    Vasomotor function of vascular endothelium was studied in 62 patients with grade 1-2 hypertension with moderate and high added risk. Methods included study of brachial and middle cerebral artery endothelium dependent and independent vasodilation/vasoconstriction, measurement of plasma levels of nitric oxide metabolites (NO(n)-), endothelin-1, and antithrombin, as well as registration of their changes during vasomotor tests with calculation of integral indexes. Most patients with hypertension differed from controls by preponderance of vasoconstrictor over vasodilator reactions both in peripheral and cerebral vascular bed. At the same time patients with hypertension had pronounced dissociation between vasomotor responses of cerebral and peripheral vessels compared with subjects with normal blood pressure (p<0.05). Besides lowered basal level of NO(n)- and high concentration of endothelin-1 patients with hypertension were characterized by hyperreactivity of nitricoxidergic system, augmented lability of endothelin producing system, and impaired athrombogenecity of vascular endothelium. Complex assessment of vasomotor function of vascular endothelium by sequential vasoactive tests characterizes functional and metabolic activity of cerebral and peripheral vessels and can be used for improvement of risk stratification and monitoring of efficacy of treatment of patients with hypertension. PMID:15111971

  12. The Discovery of Novel Genomic, Transcriptomic, and Proteomic Biomarkers in Cardiovascular and Peripheral Vascular Disease: The State of the Art

    PubMed Central

    de Franciscis, Stefano; Metzinger, Laurent; Serra, Raffaele

    2016-01-01

    Cardiovascular disease (CD) and peripheral vascular disease (PVD) are leading causes of mortality and morbidity in western countries and also responsible of a huge burden in terms of disability, functional decline, and healthcare costs. Biomarkers are measurable biological elements that reflect particular physiological or pathological states or predisposition towards diseases and they are currently widely studied in medicine and especially in CD. In this context, biomarkers can also be used to assess the severity or the evolution of several diseases, as well as the effectiveness of particular therapies. Genomics, transcriptomics, and proteomics have opened new windows on disease phenomena and may permit in the next future an effective development of novel diagnostic and prognostic medicine in order to better prevent or treat CD. This review will consider the current evidence of novel biomarkers with clear implications in the improvement of risk assessment, prevention strategies, and medical decision making in the field of CD. PMID:27298828

  13. Cross-cultural adaptation and validation of the Peripheral Artery Questionnaire: Korean version for patients with peripheral vascular diseases.

    PubMed

    Lee, Ji Hyun; Cho, Kyoung Im; Spertus, John; Kim, Seong Man

    2012-08-01

    The Peripheral Artery Questionnaire (PAQ), as developed in US English, is a validated scale to evaluate the health status of patients with peripheral artery disease (PAD). The aim of this study was to translate the PAQ into Korean and to evaluate its reliability and validity. A multi-step process of forward-translation, reconciliation, consultation with the developer, back-translation and proofreading was conducted. The test-retest reliability was evaluated at a 2-week interval using the intra-class correlation coefficient (ICC). The validity was assessed by identifying associations between Korean PAQ (KPAQ) scores and Korean Health Assessment Questionnaire (KHAQ) scores. A total of 100 PAD patients were enrolled: 63 without and 37 with severe claudication. The reliability of the KPAQ was adequate, with an ICC of 0.71. There were strong correlations between KPAQ's subscales. Cronbach's alpha for the summary score was 0.94, indicating good internal consistency and congruence with the original US version. The validity was supported by a significant correlation between the total KHAQ score and KPAQ physical function, stability, symptom, social limitation and quality of life scores (r = -0.24 to -0.90; p < 0.001) as well as between the KHAQ walking subscale and the KPAQ physical function score (r = -0.55, p < 0.001). Our results indicate that the KPAQ is a reliable, valid instrument to evaluate the health status of Korean patients with PAD. PMID:22653880

  14. Enhanced Vascular PI3K/Akt-NOX Signaling Underlies the Peripheral NMDAR-Mediated Pressor Response in Conscious Rats

    PubMed Central

    McGee, Marie A.; Abdel-Rahman, Abdel A.

    2014-01-01

    The molecular mechanisms for peripheral N-Methyl-D-Aspartate receptor (NMDAR)-mediated vascular oxidative stress and pressor response are not known. We conducted integrative (in vivo) and ex vivo biochemical studies to test the hypothesis that ROS-dependent calcium influx, triggered by activation of vascular kinases, underlies the NMDAR-mediated pressor response. Pharmacological inhibition of PI3K/Akt (Wortmannin; 15 μg/kg), PKC (Chelerythrine; 5 mg/kg, i.v.), Ca2+ influx (nifedipine; 0.35 or 0.75 mg/kg) or NOX (apocynin; 5 mg/kg) attenuated the peripheral NMDAR-mediated pressor response in conscious male Sprague-Dawley rats. NMDAR activation enhanced the phosphorylation of Akt, ERK1, JNK and p38 (Western blot) and NADPH oxidase (NOX) activity in vascular tissues collected during the pressor response caused by NMDA infusion (180 μg/kg/min, 30 min). Further, ex vivo studies showed that wortmannin, chelerythrine or apocynin abrogated the NMDAR-mediated vascular NO and ROS generation and NOX activation in the vasculature. These findings implicate vascular PI3K/Akt-PKC signaling in the peripheral NMDAR-mediated increases in vascular NO and NOX activation (ROS), which ultimately lead to calcium influx and pressor response in conscious rats. PMID:24336015

  15. Quantitative near-infrared spectroscopy on patients with peripheral vascular disease

    NASA Astrophysics Data System (ADS)

    Franceschini, Maria-Angela; Fantini, Sergio; Palumbo, Renato; Pasqualini, Leonella; Vaudo, Gaetano; Franceschini, Edoardo; Gratton, Enrico; Palumbo, Barbara; Innocente, Salvatore; Mannarino, Elmo

    1998-01-01

    We have used near-infrared spectroscopy to measure the hemoglobin saturation at rest and during exercise on patients affected by peripheral vascular disease (PVD). The instrument used in our study is a frequency-domain tissue oximeter which employs intensity modulated (110 MHz) laser diodes. We examined 9 subjects, 3 of which were controls and 6 were patients affected by stage II PVD. The optical probe was located on the calf muscle of the subjects. The measurement protocol consisted of: (1) baseline (approximately 5 min); (2) stationary bicycle exercise (approximately 5 min); (3) recovery (approximately 15 min). The change in hemoglobin saturation during exercise ((Delta) Y) and the recovery time after exercise (trec) were significantly greater in the PVD patients ((Delta) Y equals -21 +/- 3%, trec equals 5.9 +/- 3.8 min) than in the control subjects ((Delta) Y equals 2 +/- 3%, trec equals 0.6 +/- 0.1 min).

  16. Quantitative near-infrared spectroscopy on patients with peripheral vascular disease

    NASA Astrophysics Data System (ADS)

    Franceschini, Maria A.; Fantini, Sergio; Palumbo, Renato; Pasqualini, Leonella; Vaudo, Gaetano; Franceschini, Edoardo; Gratton, Enrico; Palumbo, Barbara; Innocente, Salvatore; Mannarino, Elmo

    1997-12-01

    We have used near-infrared spectroscopy to measure the hemoglobin saturation at rest and during exercise on patients affected by peripheral vascular disease (PVD). The instrument used in our study is a frequency-domain tissue oximeter which employs intensity modulated (110 MHz) laser diodes. We examined 9 subjects, 3 of which were controls and 6 were patients affected by stage II PVD. The optical probe was located on the calf muscle of the subjects. The measurement protocol consisted of: (1) baseline (approximately 5 min); (2) stationary bicycle exercise (approximately 5 min); (3) recovery (approximately 15 min). The change in hemoglobin saturation during exercise ((Delta) Y) and the recovery time after exercise (trec) were significantly greater in the PVD patients ((Delta) Y equals -21 +/- 3%, trec equals 5.9 +/- 3.8 min) than in the control subjects ((Delta) Y equals 2 +/- 3%, trec equals 0.6 +/- 0.1 min).

  17. Peripheral limb vascular malformations: an update of appropriate imaging and treatment options of a challenging condition

    PubMed Central

    Farrant, J; Chhaya, N; Anwar, I; Marmery, H; Platts, A; Holloway, B

    2015-01-01

    Peripheral vascular malformations encompass a wide spectrum of lesions that can present as an incidental finding or produce potentially life- or limb-threatening complications. They can have intra-articular and intraosseous extensions that will result in more diverse symptomology and present greater therapeutic challenges. Developments in classification, imaging and interventional techniques have helped to improve outcome. The onus is now placed on appropriate detailed preliminary imaging, diagnosis and classification to direct management and exclude other more common mimics. Radiologists are thus playing an increasingly important role in the multidisciplinary teams charged with the care of these patients. By fully understanding the imaging characteristics and image-guided procedures available, radiologists will be armed with the tools to meet these responsibilities. This review highlights the recent advances made in imaging and the options available in interventional therapy. PMID:25525685

  18. Functional preservation of vascular smooth muscle tissue

    NASA Technical Reports Server (NTRS)

    Alexander, W. C.; Hutchins, P. M.; Kimzey, S. L.

    1973-01-01

    The ionic and cellular feedback relationships operating to effect the vascular decompensatory modifications were examined to reveal procedures for implementing protective measures guarding against vascular collapse when returning from a weightless environment to that of the earth's gravity. The surgical procedures for preparing the rat cremaster, and the fixation methods are described. Abstracts of publications resulting from this research are included.

  19. Peripheral vascular effects of beta-adrenoceptor blockade: comparison of two agents.

    PubMed Central

    Cooke, E D; Maltz, M B; Smith, R E; Bowcock, S A; Watkins, C J; Camm, A J

    1987-01-01

    1. The effects of atenolol (100 mg), a beta 1-adrenoceptor blocker, and bevantolol (200 mg) were compared on heart rate, blood pressure, lung function and on the peripheral circulation in normal volunteers before and after isoprenaline infusion. Recordings were obtained 2 and 24 h following a single dose and 24 h after continuous dosage for 7 days. 2. The effect of atenolol on the blockade of beta-adrenergic stimuli, as measured by the ability to reduce isoprenaline-induced tachycardia, was greater than that of bevantolol. Though both drugs achieved a similar reduction in systolic pressure there was a significantly greater reduction in diastolic pressure with bevantolol. The lung function tests gave similar results to those with other beta-adrenoceptor blockers. 3. Atenolol produced a fall in peripheral blood flow consistent with unopposed peripheral alpha-adrenoceptor stimulation. The effect of bevantolol differs from that of atenolol, an initial fall in peripheral blood flow being followed by a rapid recovery to baseline or greater. This effect may be due to partial alpha-adrenoceptor agonist activity. PMID:2889459

  20. Serum Superoxide Dismutase Is Associated with Vascular Structure and Function in Hypertensive and Diabetic Patients.

    PubMed

    Gómez-Marcos, Manuel A; Blázquez-Medela, Ana M; Gamella-Pozuelo, Luis; Recio-Rodriguez, José I; García-Ortiz, Luis; Martínez-Salgado, Carlos

    2016-01-01

    Oxidative stress is associated with cardiac and vascular defects leading to hypertension and atherosclerosis, being superoxide dismutase (SOD) one of the main intracellular antioxidant defence mechanisms. Although several parameters of vascular function and structure have a predictive value for cardiovascular morbidity-mortality in hypertensive patients, there are no studies on the involvement of SOD serum levels with these vascular parameters. Thus, we assessed if SOD serum levels are correlated with parameters of vascular function and structure and with cardiovascular risk in hypertensive and type 2 diabetic patients. We enrolled 255 consecutive hypertensive and diabetic patients and 52 nondiabetic and nonhypertensive controls. SOD levels were measured with an enzyme-linked immunosorbent assay kit. Vascular function and structure were evaluated by pulse wave velocity, augmentation index, ambulatory arterial stiffness index, and carotid intima-media thickness. We detected negative correlations between SOD and pressure wave velocity, peripheral and central augmentation index and ambulatory arterial stiffness index, pulse pressure, and plasma HDL-cholesterol, as well as positive correlations between SOD and plasma uric acid and triglycerides. Our study shows that SOD is a marker of cardiovascular alterations in hypertensive and diabetic patients, since changes in its serum levels are correlated with alterations in vascular structure and function. PMID:26635913

  1. Serum Superoxide Dismutase Is Associated with Vascular Structure and Function in Hypertensive and Diabetic Patients

    PubMed Central

    Gómez-Marcos, Manuel A.; Blázquez-Medela, Ana M.; Gamella-Pozuelo, Luis; Recio-Rodriguez, José I.; García-Ortiz, Luis; Martínez-Salgado, Carlos

    2016-01-01

    Oxidative stress is associated with cardiac and vascular defects leading to hypertension and atherosclerosis, being superoxide dismutase (SOD) one of the main intracellular antioxidant defence mechanisms. Although several parameters of vascular function and structure have a predictive value for cardiovascular morbidity-mortality in hypertensive patients, there are no studies on the involvement of SOD serum levels with these vascular parameters. Thus, we assessed if SOD serum levels are correlated with parameters of vascular function and structure and with cardiovascular risk in hypertensive and type 2 diabetic patients. We enrolled 255 consecutive hypertensive and diabetic patients and 52 nondiabetic and nonhypertensive controls. SOD levels were measured with an enzyme-linked immunosorbent assay kit. Vascular function and structure were evaluated by pulse wave velocity, augmentation index, ambulatory arterial stiffness index, and carotid intima-media thickness. We detected negative correlations between SOD and pressure wave velocity, peripheral and central augmentation index and ambulatory arterial stiffness index, pulse pressure, and plasma HDL-cholesterol, as well as positive correlations between SOD and plasma uric acid and triglycerides. Our study shows that SOD is a marker of cardiovascular alterations in hypertensive and diabetic patients, since changes in its serum levels are correlated with alterations in vascular structure and function. PMID:26635913

  2. IMPAIRED VASCULAR ENDOTHELIAL GROWTH FACTOR-A AND INFLAMMATION IN SUBJECTS WITH PERIPHERAL ARTERY DISEASE

    PubMed Central

    Gardner, Andrew W.; Parker, Donald E.; Montgomery, Polly S.; Sosnowska, Danuta; Casanegra, Ana I.; Esponda, Omar L.; Ungvari, Zoltan; Csiszar, Anna; Sonntag, William E.

    2014-01-01

    We compared apoptosis, cellular oxidative stress, and inflammation of cultured endothelial cells treated with sera from 130 subjects with peripheral artery disease (PAD) and 36 control subjects with high burden of co-morbid conditions and cardiovascular risk factors. Secondly, we compared circulating inflammatory, antioxidant capacity, and vascular biomarkers between the groups. The groups were not significantly different (p>0.05) on apoptosis, hydrogen peroxide, hydroxyl radical antioxidant capacity, and nuclear factor k-light-chain-enhancer of activated B cells. Circulating tissue necrosis factor alpha (TNFα) (p=0.016) and interleukin-8 (p=0.006) were higher in the PAD group, whereas vascular endothelial growth factor-A (VEGF-A) (p=0.023) was lower. PAD does not impair the endothelium beyond that which already occurs from co-morbid conditions and cardiovascular risk factors in subjects with claudication. However, subjects with PAD have lower circulating VEGF-A than controls, and higher circulating inflammatory parameters of TNFα and IL-8. PMID:24006146

  3. Initial trial of argon ion laser endarterectomy for peripheral vascular disease

    SciTech Connect

    Eugene, J.; Ott, R.A.; Baribeau, Y.; McColgan, S.J.; Berns, M.W.; Mason, G.R. )

    1990-08-01

    In the initial of open laser endarterectomy, 16 patients underwent 18 reconstructions for claudication (13 patients), rest pain (3 patients), and gangrene (2 patients). The mean (+/- SD) preoperative ankle arm index was 0.53 +/- 0.18. The laser endarterectomies were aorto-bi-iliac (1 patient), iliac (1 patient), superficial femoral (7 patients), profunda femoral (7 patients), and popliteal-posterior tibial (2 patients). All operations included surgical exposure, vascular control, administration of heparin, and an arteriotomy. Atheromas were dissected from arteries with argon ion laser radiation (power, 1.0 W). End points were welded with laser light. Arteries were closed primarily. The laser endarterectomies were 6 to 60 cm long and required 168 J to 2447.5 J. All patients had symptomatic relief, with a postoperative ankle arm index of 0.97 +/- 0.10. There were no arterial perforations from laser radiation. Surgical complications included early thrombosis requiring thrombectomy (3 patients) and hematoma requiring evacuation (1 patient). The laser endarterectomies have an 88% patency at 1 year. Open endarterectomy can be performed with laser radiation. A larger clinical trial is necessary to define the indications for laser endarterectomy in peripheral vascular disease.

  4. An antiangiogenic isoform of VEGF-A contributes to impaired vascularization in peripheral artery disease.

    PubMed

    Kikuchi, Ryosuke; Nakamura, Kazuto; MacLauchlan, Susan; Ngo, Doan Thi-Minh; Shimizu, Ippei; Fuster, Jose Javier; Katanasaka, Yasufumi; Yoshida, Sumiko; Qiu, Yan; Yamaguchi, Terry P; Matsushita, Tadashi; Murohara, Toyoaki; Gokce, Noyan; Bates, David O; Hamburg, Naomi M; Walsh, Kenneth

    2014-12-01

    Peripheral artery disease (PAD) generates tissue ischemia through arterial occlusions and insufficient collateral vessel formation. Vascular insufficiency in PAD occurs despite higher circulating levels of vascular endothelial growth factor A (VEGF-A), a key regulator of angiogenesis. Here we show that clinical PAD is associated with elevated levels of an antiangiogenic VEGF-A splice isoform (VEGF-A165b) and a corresponding reduction in levels of the proangiogenic VEGF-A165a splice isoform. In mice, VEGF-A165b expression was upregulated by conditions associated with impaired limb revascularization, including leptin deficiency, diet-induced obesity, genetic ablation of the secreted frizzled-related protein 5 (Sfrp5) adipokine and transgenic overexpression of Wnt5a in myeloid cells. In a mouse model of PAD, delivery of VEGF-A165b inhibited revascularization of ischemic hind limbs, whereas treatment with an isoform-specific neutralizing antibody reversed impaired revascularization caused by metabolic dysfunction or perturbations in the Wnt5a-Sfrp5 regulatory system. These results indicate that inflammation-driven expression of the antiangiogenic VEGF-A isoform can contribute to impaired collateralization in ischemic cardiovascular disease. PMID:25362254

  5. Modular peripheral functionalization of thiophene dendrons and dendrimers.

    PubMed

    Deng, Suxiang; Sriwichai, Saengrawee; Taranekar, Prasad; Krueger, Greg; Mays, Jimmy W; Advincula, Rigoberto C

    2011-08-21

    A series of thiophene dendrons and dendrimers with peripheral functional groups were designed and synthesized. Two methodologies using thiophene dendrons and dendrons as synthetic building blocks, namely, (1) periphery functionalization; (2) a combination of focal and periphery functionalization have been demonstrated. PMID:21735024

  6. Age and sex influence the balance between maximal cardiac output and peripheral vascular reserve.

    PubMed

    Ridout, Samuel J; Parker, Beth A; Smithmyer, Sandra L; Gonzales, Joaquin U; Beck, Kenneth C; Proctor, David N

    2010-03-01

    We evaluated the influence of age and sex on the relationship between central and peripheral vasodilatory capacity. Healthy men (19 younger, 12 older) and women (17 younger, 17 older) performed treadmill and knee extensor exercise to fatigue on separate days while maximal cardiac output (Q, acetylene uptake) and peak femoral blood flow (FBF, Doppler ultrasound) were measured, respectively. Maximal Q was reduced with age similarly in men (Y: 23.6 +/- 2.7 vs. O: 17.4 +/- 3.5 l/min; P < 0.05) and women (Y: 17.7 +/- 1.9 vs. O: 12.3 +/- 1.6 l/min; P < 0.05). Peak FBF was similar between younger (Y) and older (O) men (Y: 2.1 +/- 0.5 vs. O: 2.2 +/- 0.7 l/min) but was lower in older women compared with younger women (Y: 1.9 +/- 0.4 vs. O: 1.4 +/- 0.4 l/min; P < 0.05). Maximal Q was positively correlated with peak FBF in men (Y: r = 0.55, O: r = 0.74; P < 0.05) but not in women (Y: r = 0.34, O: r = 0.10). Normalization of cardiac output to appendicular muscle mass and peak FBF to quadriceps mass reduced the correlation between these variables in younger men (r = 0.30), but the significant association remained in older men (r = 0.68; P < 0.05), with no change in women. These data suggest that 1) aerobic capacity is associated with peripheral vascular reserve in men but not women, and 2) aging is accompanied by a more pronounced sex difference in this relationship. PMID:19959767

  7. [Hearing disorders in peripheral arterial vascular diseases. A contribution on hearing loss in the aged].

    PubMed

    Böhme, G

    1987-12-01

    Otologic-audiologic examination was carried out in 171 patients (aged between 37-86; average age 64) with confirmed internal angiologic peripheral arterial vascular disease. Additional findings were observed in 94 of these patients who revealed an obliteration of the internal carotid artery or cerebral ischaemic stroke. Diseases of the ear were excluded clinically and audiologically. The mean hearing loss shows a sensory-neural high-tone loss in the tone audiogram. The range of scatter increases proportionately to the increase in tone loss. If compared with the physiologic examination of geriatric patients, the total word comprehension and minimal discrimination loss in the speech audiogram point towards a pathologic impairment of hearing in old age. The total word comprehension amounts to 251.20% in the 51-60 age group, 250.40% in the persons 61-70 years of age, 180.96% for the 71-80 age group and 131.67% for those over 80 years of age. The minimal discrimination loss comprises 4.00% for the 51-60 age group, 4.19% for the 61-70 group, 21.35% for 71-80 age bracket and 35.62% for those over 80. On the strength of these findings, an arterial sclerotic vascular disease should be considered as one of the multifactorial genesis of hearing impairment in old age. Special attention should be focussed on decompensation of the total word comprehension and minimal discrimination loss before the age of eighty. This would contribute towards a differentiation of physiologic and pathologic hearing diseases in old age. PMID:3431312

  8. Fibrin Sealant Improves Hemostasis in Peripheral Vascular Surgery: A Randomized Prospective Trial

    PubMed Central

    Schenk, Worthington G.; Burks, Sandra G.; Gagne, Paul J.; Kagan, Steven A.; Lawson, Jeffrey H.; Spotnitz, William D.

    2003-01-01

    . Conclusions FS achieved more rapid hemostasis than traditional techniques in this peripheral vascular procedure. FS use appeared to be safe for this procedure. PMID:12796584

  9. Vascular precursors: origin, regulation and function

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this miniseries, we discuss the phenotype, origin, and specialized microenvironment (niche) of distinct populations of stem and progenitor cells that exhibit vascular potential. Their usefulness and effectiveness for clinical therapies are also described. We have learned a great deal about post...

  10. Assessing vascular endothelial function using frequency and rank order statistics

    NASA Astrophysics Data System (ADS)

    Wu, Hsien-Tsai; Hsu, Po-Chun; Sun, Cheuk-Kwan; Liu, An-Bang; Lin, Zong-Lin; Tang, Chieh-Ju; Lo, Men-Tzung

    2013-08-01

    Using frequency and rank order statistics (FROS), this study analyzed the fluctuations in arterial waveform amplitudes recorded from an air pressure sensing system before and after reactive hyperemia (RH) induction by temporary blood flow occlusion to evaluate the vascular endothelial function of aged and diabetic subjects. The modified probability-weighted distance (PWD) calculated from the FROS was compared with the dilatation index (DI) to evaluate its validity and sensitivity in the assessment of vascular endothelial function. The results showed that the PWD can provide a quantitative determination of the structural changes in the arterial pressure signals associated with regulation of vascular tone and blood pressure by intact vascular endothelium after the application of occlusion stress. Our study suggests that the use of FROS is a reliable noninvasive approach to the assessment of vascular endothelial degeneration in aging and diabetes.

  11. Assessment by dipyridamole-thallium-201 myocardial scintigraphy of coronary risk before peripheral vascular surgery

    SciTech Connect

    Sachs, R.N.; Tellier, P.; Larmignat, P.; Azorin, J.; Fischbein, L.; Beaudet, B.; Cadilhac, P.; Cupa, M.; De Saint Florent, G.; Vulpillat, M.

    1988-05-01

    From October 1983 to January 1985, 46 patients (38 men and 8 women; average age, 60 years; range, 37 to 83 years) underwent peripheral vascular surgery of either the internal carotid artery or the arteries of the lower limbs. Each patient had a thorough clinical examination, an ECG, and a dipyridamole-thallium-201 myocardial scan before operation. On the basis of results, they were divided into two groups: 20 patients with and 26 patients without chronic ischemic heart disease. Three major cardiac events were noted during or after a period of 1 month after surgery: There were two deaths due to cardiac ischemic events and one patient had postoperative unstable angina pectoris. These three patients were classified in the coronary group (NS). When the patients were classified on the basis of whether or not there was thallium redistribution on serial images after infusion of dipyridamole, 14 with redistribution and 32 without redistribution were noted. The three patients who had major cardiac events were in the former group (p less than 0.04). Our data suggest that patients in whom redistribution occurs have a high incidence of postoperative ischemic events. These patients should be considered for particular preoperative coronary care to avoid major postoperative cardiac events and to increase chances of survival.

  12. A Methodological Approach to Non-invasive Assessments of Vascular Function and Morphology

    PubMed Central

    Sandoo, Aamer; Kitas, George D.

    2015-01-01

    The endothelium is the innermost lining of the vasculature and is involved in the maintenance of vascular homeostasis. Damage to the endothelium may predispose the vessel to atherosclerosis and increase the risk for cardiovascular disease. Assessments of peripheral endothelial function are good indicators of early abnormalities in the vascular wall and correlate well with assessments of coronary endothelial function. The present manuscript details the important methodological steps necessary for the assessment of microvascular endothelial function using laser Doppler imaging with iontophoresis, large vessel endothelial function using flow-mediated dilatation, and carotid atherosclerosis using carotid artery ultrasound. A discussion on the methodological considerations for each of the techniques is also presented, and recommendations are made for future research. PMID:25741637

  13. Edaravone promotes functional recovery after mechanical peripheral nerve injury

    PubMed Central

    Zhang, Teng; Li, Zhengwei; Dong, Jianli; Nan, Feng; Li, Tao; Yu, Qing

    2014-01-01

    Edaravone has been shown to reduce ischemia/reperfusion-induced peripheral nerve injury. However, the therapeutic effect of edaravone on peripheral nerve injury caused by mechanical factors is unknown. In the present study, we established a peripheral nerve injury model by crushing the sciatic nerve using hemostatic forceps, and then administered edaravone 3 mg/kg intraperitoneally. The sciatic functional index and superoxide dismutase activity of the sciatic nerve were increased, and the malondialdehyde level was decreased in animals in the edaravone group compared with those in the model group. Bcl-2 expression was increased, but Bax expression was decreased in anterior horn cells of the L4-6 spinal cord segments. These results indicated that edaravone has a neuroprotective effect following peripheral nerve injury caused by mechanical factors through alleviating free radical damage to cells and inhibiting lipid peroxidation, as well as regulating apoptosis-related protein expression. PMID:25374594

  14. Exercise and Vascular Function – How Much is too Much?

    PubMed Central

    Durand, Matthew J.; Gutterman, David D.

    2015-01-01

    Exercise is a powerful therapy for preventing the onset and slowing the progression of cardiovascular disease. Increased shear stress during exercise improves vascular homeostasis by both decreasing reactive oxygen species and increasing nitric oxide bioavailability in the endothelium. While these observations are well accepted as they apply to individuals at risk for cardiovascular disease, less is known about how exercise, especially intense exercise, affects vascular function in healthy individuals. This review highlights examples of how vascular function can paradoxically be impaired in otherwise healthy individuals by extreme levels of exercise, with a focus on the causative role that reactive oxygen species play in this impairment. PMID:24873760

  15. Sensitivity and specificity of QTc dispersion for identification of risk of cardiac death in patients with peripheral vascular disease.

    PubMed Central

    Darbar, D.; Luck, J.; Davidson, N.; Pringle, T.; Main, G.; McNeill, G.; Struthers, A. D.

    1996-01-01

    OBJECTIVE: To determine whether QTc dispersion, which is easily obtained from a standard electrocardiogram, can predict those patients with peripheral vascular disease who will subsequently suffer a cardiac death, despite having no cardiac symptoms or signs. DESIGN: Patients with peripheral vascular disease were followed up for five years after they had had coronary angiography, radionuclide ventriculography, and their QTc dispersion calculated from their 12 lead electrocardiogram. SUBJECTS: 49 such patients were then divided into three groups: survivors (34), cardiac death (12), and non-cardiac death (3). MAIN OUTCOME MEASURE: Survival. RESULTS: The mean (SD; range) ejection fractions were similar in all three groups: survivors 45.9 (11.0; 27.0-52.0), cardiac death 44.0 (7.90; 28.5-59.0), and non-cardiac death 45.3 (4.55; 39.0-50.0). QTc dispersion was significantly prolonged in the cardiac death group compared with in the survivors (86.3(23.9; 41.0-139) v 56.5 (25.4; 25.0-164); P = 0.002). A QTc dispersion > or = 60 ms had a 92% sensitivity and 81% specificity in predicting cardiac death, QTc dispersion in patients with diffuse coronary artery disease was significantly (P < 0.05) greater than in those with no disease or disease affecting one, two, or three vessels. CONCLUSIONS: There is a strong link between QTc dispersion and cardiac death in patients with peripheral vascular disease. QTc dispersion may therefore be a cheap and non-invasive way of assessing the risk of cardiac death in patients with peripheral vascular disease. PMID:8611874

  16. Time-of-day variation in vascular function.

    PubMed

    Rodrigo, G C; Denniff, M

    2016-08-01

    What is the topic of this review? This report looks at the role of endothelial nitric oxide signalling in the time-of-day variation in vasoconstriction of resistance vessels. What advances does it highlight? It highlights a time-of-day variation in contraction of mesenteric arteries, characterized by a reduced contractile response to either phenylephrine or high K(+) and increased relaxation in response to acetylcholine during the active period. This time-of-day variation in contraction results from a difference in endothelial nitric oxide synthase (eNOS) signalling that correlates with levels of eNOS expression, which peak during the active period and may have far reaching physiological consequences beyond regulation of blood pressure. There is a strong time-of-day variation in the vasoconstriction in response to sympathetic stimulation that may contribute to the time-of-day variation in blood pressure, which is characterized by a dip in blood pressure during the individual's rest period when sympathetic activity is low. Vasoconstriction is known to be regulated tightly by nitric oxide signalling from the endothelial cells, so we have looked at the effect of time-of-day on levels of endothelial nitric oxide synthase (eNOS) and vascular contractility. Mesenteric arteries isolated from the nocturnal rat exhibit a time-of-day variation in their contractile response to α1 -adrenoreceptor and muscarinic activation, which is characterized by a reduced vasoconstriction in response to phenylephrine and enhanced vasodilatation in response to acetylcholine during the rat's active period at night. An increase in eNOS signalling during the active period is responsible for this time-of-day difference in response to phenylephrine and acetylcholine and correlates with the large increase in eNOS expression (mRNA and protein) during the active period, possibly driven by the presence of a functioning peripheral circadian clock. This increase in eNOS signalling may function to

  17. [Peripheral, central and functional vertigo syndromes].

    PubMed

    Strupp, M; Dieterich, M; Zwergal, A; Brandt, T

    2015-12-01

    Depending on the temporal course, three forms of vertigo syndrome can be differentiated: 1) vertigo attacks, e.g. benign paroxysmal positional vertigo (BPPV), Menière's disease and vestibular migraine, 2) acute spontaneous vertigo lasting for days, e.g. acute unilateral vestibulopathy, brainstem or cerebellar infarction and 3) symptoms lasting for months or years, e.g. bilateral vestibulopathy and functional vertigo. The specific therapy of the various syndromes is based on three principles: 1) physical treatment with liberatory maneuvers for BPPV and balance training for vestibular deficits, 2) pharmacotherapy, e.g. for acute unilateral vestibulopathy (corticosteroids) and Menière's disease (transtympanic administration of gentamicin or steroids and high-dose betahistine therapy); placebo-controlled pharmacotherapy studies are currently being carried out for acute unilateral vestibulopathy, vestibular paroxysmia, prophylaxis of BPPV, vestibular migraine, episodic ataxia type 2 and cerebellar ataxia; 3) psychotherapy for functional dizziness. PMID:26643594

  18. Role of Peripheral Vascular Resistance for the Association Between Major Depression and Cardiovascular Disease

    PubMed Central

    Bouzinova, Elena V.; Wiborg, Ove; Aalkjaer, Christian

    2015-01-01

    Abstract: Major depression and cardiovascular diseases are 2 of the most prevalent health problems in Western society, and an association between them is generally accepted. Although the specific mechanism behind this comorbidity remains to be elucidated, it is clear that it has a complex multifactorial character including a number of neuronal, humoral, immune, and circulatory pathways. Depression-associated cardiovascular abnormalities associate with cardiac dysfunctions and with changes in peripheral resistance. Although cardiac dysfunction in association with depression has been studied in detail, little attention was given to structural and functional changes in resistance arteries responsible for blood pressure control and tissue perfusion. This review discusses recent achievements in studies of depression-associated abnormalities in resistance arteries in humans and animal experimental models. The changes in arterial structure, contractile and relaxing functions associated with depression symptoms are discussed, and the role of these abnormalities for the pathology of major depression and cardiovascular diseases are suggested. PMID:25469807

  19. Inflammatory stimuli acutely modulate peripheral taste function.

    PubMed

    Kumarhia, Devaki; He, Lianying; McCluskey, Lynnette Phillips

    2016-06-01

    Inflammation-mediated changes in taste perception can affect health outcomes in patients, but little is known about the underlying mechanisms. In the present work, we hypothesized that proinflammatory cytokines directly modulate Na(+) transport in taste buds. To test this, we measured acute changes in Na(+) flux in polarized fungiform taste buds loaded with a Na(+) indicator dye. IL-1β elicited an amiloride-sensitive increase in Na(+) transport in taste buds. In contrast, TNF-α dramatically and reversibly decreased Na(+) flux in polarized taste buds via amiloride-sensitive and amiloride-insensitive Na(+) transport systems. The speed and partial amiloride sensitivity of these changes in Na(+) flux indicate that IL-1β and TNF-α modulate epithelial Na(+) channel (ENaC) function. A portion of the TNF-mediated decrease in Na(+) flux is also blocked by the TRPV1 antagonist capsazepine, although TNF-α further reduced Na(+) transport independently of both amiloride and capsazepine. We also assessed taste function in vivo in a model of infection and inflammation that elevates these and additional cytokines. In rats administered systemic lipopolysaccharide (LPS), CT responses to Na(+) were significantly elevated between 1 and 2 h after LPS treatment. Low, normally preferred concentrations of NaCl and sodium acetate elicited high response magnitudes. Consistent with this outcome, codelivery of IL-1β and TNF-α enhanced Na(+) flux in polarized taste buds. These results demonstrate that inflammation elicits swift changes in Na(+) taste function, which may limit salt consumption during illness. PMID:27009163

  20. The Adventitia: Essential Regulator of Vascular Wall Structure and Function

    PubMed Central

    Stenmark, Kurt R.; Yeager, Michael E.; El Kasmi, Karim C.; Nozik-Grayck, Eva; Gerasimovskaya, Evgenia V.; Li, Min; Riddle, Suzette R.; Frid, Maria G.

    2013-01-01

    The vascular adventitia acts as a biological processing center for the retrieval, integration, storage, and release of key regulators of vessel wall function. It is the most complex compartment of the vessel wall and is comprised of a variety of cells including fibroblasts, immunomodulatory cells (dendritic and macrophages), progenitor cells, vasa vasorum endothelial cells and pericytes, and adrenergic nerves. In response to vascular stress or injury, resident adventitial cells are often the first to be activated and re-programmed to then influence tone and structure of the vessel wall, to initiate and perpetuate chronic vascular inflammation, and to act to stimulate expansion of the vasa vasorum, which can act as a conduit for continued inflammatory and progenitor cell delivery to the vessel wall. This review presents the current evidence demonstrating that the adventitia acts as a key regulator of vascular wall function and structure from the “outside-in.” PMID:23216413

  1. The adventitia: essential regulator of vascular wall structure and function.

    PubMed

    Stenmark, Kurt R; Yeager, Michael E; El Kasmi, Karim C; Nozik-Grayck, Eva; Gerasimovskaya, Evgenia V; Li, Min; Riddle, Suzette R; Frid, Maria G

    2013-01-01

    The vascular adventitia acts as a biological processing center for the retrieval, integration, storage, and release of key regulators of vessel wall function. It is the most complex compartment of the vessel wall and is composed of a variety of cells, including fibroblasts, immunomodulatory cells (dendritic cells and macrophages), progenitor cells, vasa vasorum endothelial cells and pericytes, and adrenergic nerves. In response to vascular stress or injury, resident adventitial cells are often the first to be activated and reprogrammed to influence the tone and structure of the vessel wall; to initiate and perpetuate chronic vascular inflammation; and to stimulate expansion of the vasa vasorum, which can act as a conduit for continued inflammatory and progenitor cell delivery to the vessel wall. This review presents the current evidence demonstrating that the adventitia acts as a key regulator of vascular wall function and structure from the outside in. PMID:23216413

  2. Effects of short-term endurance exercise training on vascular function in young males.

    PubMed

    Currie, Katharine D; Thomas, Scott G; Goodman, Jack M

    2009-09-01

    We investigated effects of 6 days of endurance exercise training [cycling at 65% of peak oxygen consumption (VO(2peak)) for 2 h a day on six consecutive days] on vascular function in young males. Measures of VO(2peak), arterial stiffness, calf vascular conductance and heart rate variability were obtained pre- and post-training. Indices of arterial stiffness were obtained by applanation tonometry to determine aortic augmentation index normalized to a heart rate of 75 bpm (AI(x) at 75 bpm), and central and peripheral pulse wave velocity (CPWV, PPWV). Resting and maximal calf vascular conductances were calculated from concurrent measures of blood pressure and calf blood flow using venous occlusion strain-gauge plethysmography. Time and frequency domain measures of heart rate variability were obtained from recording R-R intervals during supine and standing conditions. Both CPWV (5.9 +/- 0.8 vs. 5.4 +/- 0.8 m/s) and PPWV (9.7 +/- 0.8 vs. 8.9 +/- 1.3 m/s) were reduced following the training program. No significant changes were observed in AI(x) at 75 bpm, vascular conductance, heart rate variability or VO(2peak). These data indicate that changes in arterial stiffness independent of changes in heart rate variability or vascular conductance can be achieved in healthy young males following only 6 days of intense endurance exercise. PMID:19554346

  3. Macrophages in Vascular Inflammation: Origins and Functions.

    PubMed

    Decano, Julius L; Mattson, Peter C; Aikawa, Masanori

    2016-06-01

    Macrophages influence various processes of cardiovascular inflammation. Whether they are of embryonic or post-natal hematopoietic origin, their balance in differential activation may direct the course of inflammation. Accelerated macrophage activation and accumulation through a pro-inflammatory signaling pathway may result in extensive tissue damage, adverse repair, and worsened clinical outcomes. Attenuation of such a mechanism and/or promotion of the anti-inflammatory macrophage activation may lead to early resolution of inflammation. Elucidating multiple novel mechanisms of monocyte and macrophage activation leads to a better understanding of their roles in vascular inflammation. In turn, this begets better therapeutic target identification and biomarker discovery. Combined with increasingly sensitive and specific imaging techniques, we continue to push back early detection and monitoring to provide us with a greater window for disease modification. The potential success of cytokine-targeted therapy will be solid proof of the inflammatory hypothesis of atherothrombosis. PMID:27125207

  4. Hindlimb unweighting affects rat vascular capacitance function

    NASA Technical Reports Server (NTRS)

    Dunbar, S. L.; Tamhidi, L.; Berkowitz, D. E.; Shoukas, A. A.

    2001-01-01

    Microgravity is associated with an impaired stroke volume and, therefore, cardiac output response to orthostatic stress. We hypothesized that a decreased venous filling pressure due to increased venous compliance may be an important contributing factor in this response. We used a constant flow, constant right atrial pressure cardiopulmonary bypass procedure to measure total systemic vascular compliance (C(T)), arterial compliance (C(A)), and venous compliance (C(V)) in seven control and seven 21-day hindlimb unweighted (HLU) rats. These compliance values were calculated under baseline conditions and during an infusion of 0.2 microg*kg(-1)*min(-1) norepinephrine (NE). The change in reservoir volume, which reflects changes in unstressed vascular volume (DeltaV(0)) that occurred upon infusion of NE, was also measured. C(T) and C(V) were larger in HLU rats both at baseline and during the NE infusion (P < 0.05). Infusion of NE decreased C(T) and C(V) by 20% in both HLU and control rats (P < 0.01). C(A) was also significantly decreased in both groups of rats by NE (P < 0.01), but values of C(A) were similar between HLU and control rats both at baseline and during the NE infusion. Additionally, the NE-induced DeltaV(0) was attenuated by 53% in HLU rats compared with control rats (P < 0.05). The larger C(V) and attenuated DeltaV(0) in HLU rats could contribute to a decreased filling pressure during orthostasis and thus may partially underlie the mechanism leading to the exaggerated fall in stroke volume and cardiac output seen in astronauts during an orthostatic stress after exposure to microgravity.

  5. Effects of chronic peripheral olfactory loss on functional brain networks.

    PubMed

    Kollndorfer, K; Jakab, A; Mueller, C A; Trattnig, S; Schöpf, V

    2015-12-01

    The effects of sensory loss on central processing in various sensory systems have already been described. The olfactory system holds the special ability to be activated by a sensorimotor act, without the presentation of an odor. In this study, we investigated brain changes related to chronic peripheral smell loss. We included 11 anosmic patients (eight female, three male; mean age, 43.5 years) with smell loss after an infection of the upper respiratory tract (mean disease duration, 4.64 years) and 14 healthy controls (seven female, seven male; mean age, 30.1 years) in a functional magnetic resonance imaging experiment with a sniffing paradigm. Data were analyzed using group-independent component analysis and functional connectivity analysis. Our results revealed a spatially intact olfactory network in patients, whereas major aberrations due to peripheral loss were observed in functional connectivity through a variety of distributed brain areas. This is the first study to show the re-organization caused by the lack of peripheral input. The results of this study indicate that anosmic patients hold the ability to activate an olfaction-related functional network through the sensorimotor component of odor-perception (sniffing). The areas involved were not different from those that emerged in healthy controls. However, functional connectivity appears to be different between the two groups, with a decrease in functional connectivity in the brain in patients with chronic peripheral sensory loss. We can further conclude that the loss of the sense of smell may induce far-reaching effects in the whole brain, which lead to compensatory mechanisms from other sensory systems due to the close interconnectivity of the olfactory system with other functional networks. PMID:26415766

  6. Systemic vascular function is associated with muscular power in adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-associated loss of muscular strength and muscular power are critical determinants of loss of physical function and progression to disability in older adults. In this study, we examined the association of systemic vascular function and measures of muscle strength and power in older adults. Measu...

  7. Functional Human Vascular Network Generated in Photocrosslinkable Gelatin Methacrylate Hydrogels.

    PubMed

    Chen, Ying-Chieh; Lin, Ruei-Zeng; Qi, Hao; Yang, Yunzhi; Bae, Hojae; Melero-Martin, Juan M; Khademhosseini, Ali

    2012-05-23

    The generation of functional, 3D vascular networks is a fundamental prerequisite for the development of many future tissue engineering-based therapies. Current approaches in vascular network bioengineering are largely carried out using natural hydrogels as embedding scaffolds. However, most natural hydrogels present a poor mechanical stability and a suboptimal durability, which are critical limitations that hamper their widespread applicability. The search for improved hydrogels has become a priority in tissue engineering research. Here, the suitability of a photopolymerizable gelatin methacrylate (GelMA) hydrogel to support human progenitor cell-based formation of vascular networks is demonstrated. Using GelMA as the embedding scaffold, it is shown that 3D constructs containing human blood-derived endothelial colony-forming cells (ECFCs) and bone marrow-derived mesenchymal stem cells (MSCs) generate extensive capillary-like networks in vitro. These vascular structures contain distinct lumens that are formed by the fusion of ECFC intracellular vacuoles in a process of vascular morphogenesis. The process of vascular network formation is dependent on the presence of MSCs, which differentiate into perivascular cells occupying abluminal positions within the network. Importantly, it is shown that implantation of cell-laden GelMA hydrogels into immunodeficient mice results in a rapid formation of functional anastomoses between the bioengineered human vascular network and the mouse vasculature. Furthermore, it is shown that the degree of methacrylation of the GelMA can be used to modulate the cellular behavior and the extent of vascular network formation both in vitro and in vivo. These data suggest that GelMA hydrogels can be used for biomedical applications that require the formation of microvascular networks, including the development of complex engineered tissues. PMID:22907987

  8. Functional Human Vascular Network Generated in Photocrosslinkable Gelatin Methacrylate Hydrogels

    PubMed Central

    Chen, Ying-Chieh; Lin, Ruei-Zeng; Qi, Hao; Yang, Yunzhi; Bae, Hojae

    2012-01-01

    The generation of functional, 3D vascular networks is a fundamental prerequisite for the development of many future tissue engineering-based therapies. Current approaches in vascular network bioengineering are largely carried out using natural hydrogels as embedding scaffolds. However, most natural hydrogels present a poor mechanical stability and a suboptimal durability, which are critical limitations that hamper their widespread applicability. The search for improved hydrogels has become a priority in tissue engineering research. Here, the suitability of a photopolymerizable gelatin methacrylate (GelMA) hydrogel to support human progenitor cell-based formation of vascular networks is demonstrated. Using GelMA as the embedding scaffold, it is shown that 3D constructs containing human blood-derived endothelial colony-forming cells (ECFCs) and bone marrow-derived mesenchymal stem cells (MSCs) generate extensive capillary-like networks in vitro. These vascular structures contain distinct lumens that are formed by the fusion of ECFC intracellular vacuoles in a process of vascular morphogenesis. The process of vascular network formation is dependent on the presence of MSCs, which differentiate into perivascular cells occupying abluminal positions within the network. Importantly, it is shown that implantation of cell-laden GelMA hydrogels into immunodeficient mice results in a rapid formation of functional anastomoses between the bioengineered human vascular network and the mouse vasculature. Furthermore, it is shown that the degree of methacrylation of the GelMA can be used to modulate the cellular behavior and the extent of vascular network formation both in vitro and in vivo. These data suggest that GelMA hydrogels can be used for biomedical applications that require the formation of microvascular networks, including the development of complex engineered tissues. PMID:22907987

  9. Hybrid Therapy in Patients with Complex Peripheral Multifocal Steno-obstructive Vascular Disease: Two-Year Results

    SciTech Connect

    Cotroneo, Antonio Raffaele; Iezzi, Roberto Marano, Giuseppe; Fonio, Paolo; Nessi, Franco; Gandini, Giovanni

    2007-06-15

    Purpose. To report the 2-year results after hybrid (combined surgical-endovascular) therapy in patients with complex peripheral multifocal steno-obstructive vascular disease. Methods. From September 2001 through April 2003, 47 combined surgical-endovascular procedures were performed in a single session in 44 patients with peripheral occlusive artery disease. Although the common femoral artery is usually treated with open surgery, endoluminal procedures were performed upward in 23 patients (group A), distally in 18 patients (group B), and both upward and downward of the area treated with open surgery in 3 patients (group C). Patients underwent clinical assessment and color duplex ultrasonography examination at 1, 3, 6, 12, 18, and 24 months after the procedure. Results. The technical success rate was 100%. Two patients died, at 2 and 19 months after treatment, respectively, both from myocardial infarction. Primary and primary-assisted patency rates were 86.2% and 90.8% at 6 months and 79.1% and 86.1% at 24 months, respectively. Thirty-three patients remained free of symptoms, without any secondary interventions, which corresponded to a primary patency rate of 78.6% (33 of 42). Conclusion. Combined therapy simplifies and allows the one-step treatment of patients with complex peripheral multifocal steno-obstructive vascular disease that has indications for revascularization, and it provides excellent long-term patency rates.

  10. Dynamic fluorescence imaging of indocyanine green for reliable and sensitive diagnosis of peripheral vascular insufficiency.

    PubMed

    Kang, Yujung; Lee, Jungsul; Kwon, Kihwan; Choi, Chulhee

    2010-12-01

    Quantitative measurement of functional tissue perfusion is essential for early diagnosis and proper treatment of peripheral arterial occlusive disease (PAOD). We have previously demonstrated that dynamic imaging of near-infrared fluorophore indocyanine green (ICG) can be a noninvasive and sensitive tool to measure tissue perfusion. In the present study, we investigated the clinical efficacy of ICG perfusion imaging method for the diagnosis of PAOD. Total nineteen PAOD patients and age-matched controls (n=10) were evaluated for lower extremity tissue perfusion using ICG perfusion imaging. The perfusion rates of the lower extremities with severe PAOD (n=25 legs, 16.6±8.3%/min) were significantly lower than those of normal controls (38.1±17.3%/min, p<0.001). In cases of mild PAOD, the perfusion rates (n=11 legs, 18.3±10.3%/min) were also significantly lower compared to the control; while the conventional ankle-brachial index (ABI) test failed to detect mild functional impairment. These results collectively indicate that ICG perfusion imaging can be a very effective tool for diagnosis of PAOD with a superior efficacy in comparison to conventional ABI test. PMID:20637783

  11. [Search for Factors Related to Vascular Pain Expression upon Administration of Oxaliplatin into a Peripheral Vein].

    PubMed

    Takagi, Akiko; Yonemoto, Nao; Aoyama, Yuuya; Touma, Yuri; Kajiwara, Michiko; Watanabe, Kosuke; Miyazaki, Yoshiko; Koinuma, Masayoshi

    2015-07-01

    We investigated the relationship between vascular pain and various characteristics (age, sex, cancer stage, performance status [PS], height, weight, body mass index [BMI], body surface area, oxaliplatin dose, and presence and absence of the initial administration of dexamethasone) in colorectal cancer patients who were administered initial doses of oxaliplatin intravenously. The study population included 29 patients treated at Higashi Totsuka Memorial Hospital between June 2010 and April 2014. One-way analysis of variance showed that vascular pain was significantly associated with weight (p=0.015), body surface area (p=0.013), and oxaliplatin doses (p=0.0026), where the significance level was p=0.05. Logistic regression analysis and the likelihood ratio test demonstrated that the likelihood of vascular pain increased with the increase in the oxaliplatin dose. According to the cut-off value of vascular pain determined using the receiver operating characteristic (ROC) analysis, a single dose of oxaliplatin was determined to be 175 mg or more. According to the cut-off value established using the ROC analysis, a single dose of oxaliplatin at which vascular pain is expressed was determined to be 175 mg or more. At this dose, 13 patients complained of vascular pain and 8 did not. At doses less than 175 mg, none of the 8 patients complained of vascular pain. These results suggest that lowering the diluted concentration and reducing the infusion rate of intravenously administered oxaliplatin may reduce vascular pain. PMID:26197757

  12. In vitro assessment of mouse fetal abdominal aortic vascular function

    PubMed Central

    Dilworth, Mark R.; Greenwood, Susan L.; Sibley, Colin P.; Wareing, Mark

    2014-01-01

    Fetal growth restriction (FGR) affects 3–8% of human pregnancies. Mouse models have provided important etiological data on FGR; they permit the assessment of treatment strategies on the physiological function of both mother and her developing offspring. Our study aimed to 1) develop a method to assess vascular function in fetal mice and 2) as a proof of principle ascertain whether a high dose of sildenafil citrate (SC; Viagra) administered to the pregnant dam affected fetal vascular reactivity. We developed a wire myography methodology for evaluation of fetal vascular function in vitro using the placenta-specific insulin-like growth factor II (Igf2) knockout mouse (P0; a model of FGR). Vascular function was determined in abdominal aortas isolated from P0 and wild-type (WT) fetuses at embryonic day (E) 18.5 of gestation. A subset of dams received SC 0.8 mg/ml via drinking water from E12.5; data were compared with water-only controls. Using wire myography, we found that fetal aortic rings exhibited significant agonist-induced contraction, and endothelium-dependent and endothelium-independent relaxation. Sex-specific alterations in reactivity were noted in both strains. Maternal treatment with SC significantly attenuated endothelium-dependent and endothelium-independent relaxation of fetal aortic rings. Mouse fetal abdominal aortas reproducibly respond to vasoactive agents. Study of these vessels in mouse genetic models of pregnancy complications may 1) help to delineate early signs of abnormal vascular reactivity and 2) inform whether treatments given to the mother during pregnancy may impact upon fetal vascular function. PMID:25056105

  13. Mineralocorticoid Receptors Modulate Vascular Endothelial Function in Human Obesity

    PubMed Central

    Hwang, Moon-Hyon; Yoo, Jeung-Ki; Luttrell, Meredith; Kim, Han-Kyul; Meade, Thomas H.; English, Mark; Segal, Mark S.; Christou, Demetra D.

    2015-01-01

    Obesity increases linearly with age and is associated with impaired vascular endothelial function and increased risk for cardiovascular disease. Mineralocorticoid receptors (MR) contribute to impaired vascular endothelial function in cardiovascular disease; however, their role in uncomplicated human obesity is unknown. Because plasma aldosterone levels are elevated in obesity and adipocytes may be a source of aldosterone, we hypothesized that MR modulate vascular endothelial function in older adults in an adiposity-dependent manner. To test this hypothesis, we administered MR blockade (Eplerenone; 100 mg/day) for 1 month in a balanced, randomized, double-blind, placebo-controlled, crossover study to 22 older adults (10 men, 55–79 years) varying widely in adiposity (body mass index: 20–45 kg/m2) but who were free from overt cardiovascular disease. We evaluated vascular endothelial function (brachial artery flow-mediated dilation [FMD] via ultrasonography) and oxidative stress (plasma F2-isoprostanes and vascular endothelial cell protein expression of nitrotyrosine and NADPH oxidase p47phox) during placebo and MR blockade. In the whole group, oxidative stress (P>0.05) and FMD did not change with MR blockade (6.39±0.67 vs. 6.23±0.73 %, P=0.7, placebo vs. Eplerenone). However, individual improvements in FMD in response to Eplerenone were associated with higher total body fat (body mass index: r=0.45, P=0.02 and DXA-derived % body fat: r=0.50, P=0.009) and abdominal fat (total: r=0.61, P=0.005, visceral: r=0.67, P=0.002 and subcutaneous: r=0.48, P=0.03). In addition, greater improvements in FMD with Eplerenone were related with higher baseline fasting glucose (r=0.53, P=0.01). MR influence vascular endothelial function in an adiposity-dependent manner in healthy older adults. PMID:23786536

  14. Dcc Mediates Functional Assembly of Peripheral Auditory Circuits

    PubMed Central

    Kim, Young J.; Wang, Sheng-zhi; Tymanskyj, Stephen; Ma, Le; Tao, Huizhong W.; Zhang, Li I.

    2016-01-01

    Proper structural organization of spiral ganglion (SG) innervation is crucial for normal hearing function. However, molecular mechanisms underlying the developmental formation of this precise organization remain not well understood. Here, we report in the developing mouse cochlea that deleted in colorectal cancer (Dcc) contributes to the proper organization of spiral ganglion neurons (SGNs) within the Rosenthal’s canal and of SGN projections toward both the peripheral and central auditory targets. In Dcc mutant embryos, mispositioning of SGNs occurred along the peripheral auditory pathway with misrouted afferent fibers and reduced synaptic contacts with hair cells. The central auditory pathway simultaneously exhibited similar defective phenotypes as in the periphery with abnormal exit of SGNs from the Rosenthal’s canal towards central nuclei. Furthermore, the axons of SGNs ascending into the cochlear nucleus had disrupted bifurcation patterns. Thus, Dcc is necessary for establishing the proper spatial organization of SGNs and their fibers in both peripheral and central auditory pathways, through controlling axon targeting and cell migration. Our results suggest that Dcc plays an important role in the developmental formation of peripheral and central auditory circuits, and its mutation may contribute to sensorineural hearing loss. PMID:27040640

  15. Catheter Securement Systems for Peripherally Inserted and Nontunneled Central Vascular Access Devices: Clinical Evaluation of a Novel Sutureless Device.

    PubMed

    Krenik, Karen M; Smith, Graham E; Bernatchez, Stéphanie F

    2016-01-01

    Sutureless catheter securement systems are intended to eliminate risks associated with sutures. The clinical acceptability of a novel system was investigated compared with the current method of securement for peripherally inserted central catheters (19 facilities using StatLock or sutures) or nontunneled central vascular access devices (3 facilities using StatLock or sutures or HubGuard + Sorbaview Shield). More than 94% of respondents rated the novel system as same, better, or much better than their current product. More than 82% of respondents were willing to replace their current system with the new one. PMID:27379679

  16. Silent myocardial ischemia and infarction in diabetics with peripheral vascular disease: Assessment by dipyridamole thallium-201 scintigraphy

    SciTech Connect

    Nesto, R.W.; Watson, F.S.; Kowalchuk, G.J.; Zarich, S.W.; Hill, T.; Lewis, S.M.; Lane, S.E. )

    1990-11-01

    We investigated the incidence of silent myocardial ischemia and infarction as assessed by dipyridamole thallium scintigraphy in 30 diabetic patients with peripheral vascular disease and without clinical suspicion of coronary artery disease. Seventeen patients (57%) had thallium abnormalities, with reversible thallium defects compatible with ischemia in 14 patients (47%) and evidence of prior, clinically silent myocardial infarction in 11 patients (37%). Thallium abnormalities were most frequent in patients with concomitant hypertension and cigarette smoking (p = 0.001). These results suggest that unsuspected coronary artery disease is common in this particular group of patients with diabetes mellitus.

  17. Reporting standards of the Society for Vascular Surgery for endovascular treatment of chronic lower extremity peripheral artery disease: Executive summary.

    PubMed

    Stoner, Michael C; Calligaro, Keith D; Chaer, Rabih A; Dietzek, Alan M; Farber, Alik; Guzman, Raul J; Hamdan, Allen D; Landry, Greg J; Yamaguchi, Dean J

    2016-07-01

    Recommended reporting standards for lower extremity ischemia were last published by the Society for Vascular Surgery in 1997. Since that time, there has been a proliferation of endovascular therapies for the treatment of chronic peripheral arterial disease. The purpose of this document is to clarify and update these standards, specifically for reports on endovascular treatment. The document is divided into sections: Claudication Reporting, Critical Limb Ischemia Reporting, Preintervention Assessment and Nonanatomic Treatment, Intervention, Outcome Measures - Procedural, Outcome Measures - Disease Specific, and Complications. PMID:27345507

  18. Regulation of thrombosis and vascular function by protein methionine oxidation.

    PubMed

    Gu, Sean X; Stevens, Jeff W; Lentz, Steven R

    2015-06-18

    Redox biology is fundamental to both normal cellular homeostasis and pathological states associated with excessive oxidative stress. Reactive oxygen species function not only as signaling molecules but also as redox regulators of protein function. In the vascular system, redox reactions help regulate key physiologic responses such as cell adhesion, vasoconstriction, platelet aggregation, angiogenesis, inflammatory gene expression, and apoptosis. During pathologic states, altered redox balance can cause vascular cell dysfunction and affect the equilibrium between procoagulant and anticoagulant systems, contributing to thrombotic vascular disease. This review focuses on the emerging role of a specific reversible redox reaction, protein methionine oxidation, in vascular disease and thrombosis. A growing number of cardiovascular and hemostatic proteins are recognized to undergo reversible methionine oxidation, in which methionine residues are posttranslationally oxidized to methionine sulfoxide. Protein methionine oxidation can be reversed by the action of stereospecific enzymes known as methionine sulfoxide reductases. Calcium/calmodulin-dependent protein kinase II is a prototypical methionine redox sensor that responds to changes in the intracellular redox state via reversible oxidation of tandem methionine residues in its regulatory domain. Several other proteins with oxidation-sensitive methionine residues, including apolipoprotein A-I, thrombomodulin, and von Willebrand factor, may contribute to vascular disease and thrombosis. PMID:25900980

  19. Regulation of thrombosis and vascular function by protein methionine oxidation

    PubMed Central

    Gu, Sean X.; Stevens, Jeff W.

    2015-01-01

    Redox biology is fundamental to both normal cellular homeostasis and pathological states associated with excessive oxidative stress. Reactive oxygen species function not only as signaling molecules but also as redox regulators of protein function. In the vascular system, redox reactions help regulate key physiologic responses such as cell adhesion, vasoconstriction, platelet aggregation, angiogenesis, inflammatory gene expression, and apoptosis. During pathologic states, altered redox balance can cause vascular cell dysfunction and affect the equilibrium between procoagulant and anticoagulant systems, contributing to thrombotic vascular disease. This review focuses on the emerging role of a specific reversible redox reaction, protein methionine oxidation, in vascular disease and thrombosis. A growing number of cardiovascular and hemostatic proteins are recognized to undergo reversible methionine oxidation, in which methionine residues are posttranslationally oxidized to methionine sulfoxide. Protein methionine oxidation can be reversed by the action of stereospecific enzymes known as methionine sulfoxide reductases. Calcium/calmodulin-dependent protein kinase II is a prototypical methionine redox sensor that responds to changes in the intracellular redox state via reversible oxidation of tandem methionine residues in its regulatory domain. Several other proteins with oxidation-sensitive methionine residues, including apolipoprotein A-I, thrombomodulin, and von Willebrand factor, may contribute to vascular disease and thrombosis. PMID:25900980

  20. Role of Mitochondria in Cerebral Vascular Function: Energy Production, Cellular Protection, and Regulation of Vascular Tone.

    PubMed

    Busija, David W; Rutkai, Ibolya; Dutta, Somhrita; Katakam, Prasad V

    2016-01-01

    Mitochondria not only produce energy in the form of ATP to support the activities of cells comprising the neurovascular unit, but mitochondrial events, such as depolarization and/or ROS release, also initiate signaling events which protect the endothelium and neurons against lethal stresses via pre-/postconditioning as well as promote changes in cerebral vascular tone. Mitochondrial depolarization in vascular smooth muscle (VSM), via pharmacological activation of the ATP-dependent potassium channels on the inner mitochondrial membrane (mitoKATP channels), leads to vasorelaxation through generation of calcium sparks by the sarcoplasmic reticulum and subsequent downstream signaling mechanisms. Increased release of ROS by mitochondria has similar effects. Relaxation of VSM can also be indirectly achieved via actions of nitric oxide (NO) and other vasoactive agents produced by endothelium, perivascular and parenchymal nerves, and astroglia following mitochondrial activation. Additionally, NO production following mitochondrial activation is involved in neuronal preconditioning. Cerebral arteries from female rats have greater mitochondrial mass and respiration and enhanced cerebral arterial dilation to mitochondrial activators. Preexisting chronic conditions such as insulin resistance and/or diabetes impair mitoKATP channel relaxation of cerebral arteries and preconditioning. Surprisingly, mitoKATP channel function after transient ischemia appears to be retained in the endothelium of large cerebral arteries despite generalized cerebral vascular dysfunction. Thus, mitochondrial mechanisms may represent the elusive signaling link between metabolic rate and blood flow as well as mediators of vascular change according to physiological status. Mitochondrial mechanisms are an important, but underutilized target for improving vascular function and decreasing brain injury in stroke patients. © 2016 American Physiological Society. Compr Physiol 6:1529-1548, 2016. PMID:27347901

  1. Vascular function in diabetic individuals in association with particulate matter

    EPA Science Inventory

    Rationale: Exposure to ambient air pollution has been shown to be associated with cardiovascular effects, especially in people with chronic diseases such as diabetes. The purpose of this study was to analyze the short-term effects of air pollution on vascular function in two pane...

  2. Abnormalities of vascular structure and function in pediatric hypertension.

    PubMed

    Urbina, Elaine M

    2016-07-01

    Hypertension is associated with adverse cardiovascular (CV) events in adults. Measures of vascular structure and function, including increased carotid intima-media thickness (cIMT) and elevated arterial stiffness predict hard CV events in adulthood. Newer data suggest that abnormalities in target organ damage are occurring in adolescents and young adults with high blood pressure. In this review, we discuss the techniques for measuring vascular dysfunction in young people and the evidence linking blood pressure levels to this type of target organ damage. PMID:26275663

  3. Quantitative optical imaging of vascular response in vivo in a model of peripheral arterial disease.

    PubMed

    Poole, Kristin M; Tucker-Schwartz, Jason M; Sit, Wesley W; Walsh, Alex J; Duvall, Craig L; Skala, Melissa C

    2013-10-15

    The mouse hind limb ischemia (HLI) model is well established for studying collateral vessel formation and testing therapies for peripheral arterial disease, but there is a lack of quantitative techniques for intravitally analyzing blood vessel structure and function. To address this need, non-invasive, quantitative optical imaging techniques were developed to assess the time-course of recovery in the mouse HLI model. Hyperspectral imaging and optical coherence tomography (OCT) were used to non-invasively image hemoglobin oxygen saturation and microvessel morphology plus blood flow, respectively, in the anesthetized mouse after induction of HLI. Hyperspectral imaging detected significant increases in hemoglobin saturation in the ischemic paw as early as 3 days after femoral artery ligation (P < 0.01), and significant increases in distal blood flow were first detected with OCT 14 days postsurgery (P < 0.01). Intravital OCT images of the adductor muscle vasculature revealed corkscrew collateral vessels characteristic of the arteriogenic response to HLI. The hyperspectral imaging and OCT data significantly correlated with each other and with laser Doppler perfusion imaging (LDPI) and tissue oxygenation sensor data (P < 0.01). However, OCT measurements acquired depth-resolved information and revealed more sustained flow deficits following surgery that may be masked by more superficial measurements (LDPI, hyperspectral imaging). Therefore, intravital OCT may provide a robust biomarker for the late stages of ischemic limb recovery. This work validates non-invasive acquisition of both functional and morphological data with hyperspectral imaging and OCT. Together, these techniques provide cardiovascular researchers an unprecedented and comprehensive view of the temporal dynamics of HLI recovery in living mice. PMID:23955718

  4. Quantitative optical imaging of vascular response in vivo in a model of peripheral arterial disease

    PubMed Central

    Poole, Kristin M.; Tucker-Schwartz, Jason M.; Sit, Wesley W.; Walsh, Alex J.; Duvall, Craig L.

    2013-01-01

    The mouse hind limb ischemia (HLI) model is well established for studying collateral vessel formation and testing therapies for peripheral arterial disease, but there is a lack of quantitative techniques for intravitally analyzing blood vessel structure and function. To address this need, non-invasive, quantitative optical imaging techniques were developed to assess the time-course of recovery in the mouse HLI model. Hyperspectral imaging and optical coherence tomography (OCT) were used to non-invasively image hemoglobin oxygen saturation and microvessel morphology plus blood flow, respectively, in the anesthetized mouse after induction of HLI. Hyperspectral imaging detected significant increases in hemoglobin saturation in the ischemic paw as early as 3 days after femoral artery ligation (P < 0.01), and significant increases in distal blood flow were first detected with OCT 14 days postsurgery (P < 0.01). Intravital OCT images of the adductor muscle vasculature revealed corkscrew collateral vessels characteristic of the arteriogenic response to HLI. The hyperspectral imaging and OCT data significantly correlated with each other and with laser Doppler perfusion imaging (LDPI) and tissue oxygenation sensor data (P < 0.01). However, OCT measurements acquired depth-resolved information and revealed more sustained flow deficits following surgery that may be masked by more superficial measurements (LDPI, hyperspectral imaging). Therefore, intravital OCT may provide a robust biomarker for the late stages of ischemic limb recovery. This work validates non-invasive acquisition of both functional and morphological data with hyperspectral imaging and OCT. Together, these techniques provide cardiovascular researchers an unprecedented and comprehensive view of the temporal dynamics of HLI recovery in living mice. PMID:23955718

  5. Pressor response to intravenous tyramine is a marker of cardiac, but not vascular, adrenergic function

    NASA Technical Reports Server (NTRS)

    Meck, Janice V.; Martin, David S.; D'Aunno, Dominick S.; Waters, Wendy W.

    2003-01-01

    Intravenous injections of the indirect sympathetic amine, tyramine, are used as a test of peripheral adrenergic function. The authors measured the time course of increases in ejection fraction, heart rate, systolic and diastolic pressure, popliteal artery flow, and greater saphenous vein diameter before and after an injection of 4.0 mg/m(2) body surface area of tyramine in normal human subjects. The tyramine caused moderate, significant increases in systolic pressure and significant decreases in total peripheral resistance. The earliest changes were a 30% increase in ejection fraction and a 16% increase in systolic pressure, followed by a 60% increase in popliteal artery flow and a later 11% increase in greater saphenous vein diameter. There were no changes in diastolic pressure or heart rate. These results suggest that pressor responses during tyramine injections are primarily due to an inotropic response that increases cardiac output and pressure and causes a reflex decrease in vascular resistance. Thus, tyramine pressor tests are a measure of cardiac, but not vascular, sympathetic function.

  6. Collagen VI regulates peripheral nerve myelination and function.

    PubMed

    Chen, Peiwen; Cescon, Matilde; Megighian, Aram; Bonaldo, Paolo

    2014-03-01

    Collagen VI is an extracellular matrix protein with broad distribution in several tissues. Although Col6a1 is expressed by Schwann cells, the role of collagen VI in the peripheral nervous system (PNS) is yet unknown. Here we show that Schwann cells, but not axons, contribute to collagen VI deposition in peripheral nerves. By using Col6a1-null mice, in which collagen VI deposition is compromised, we demonstrate that lack of collagen VI leads to increased myelin thickness (P<0.001) along with 60-130% up-regulation in myelin-associated proteins and disorganized C fibers in the PNS. The hypermyelination of PNS in Col6a1(-/-) mice is supported by alterations of signaling pathways involved in myelination, including increase of P-FAK, P-AKT, P-ERK1, P-ERK2, and P-p38 (4.15, 1.67, 2.47, 3.34, and 2.60-fold, respectively) and reduction of vimentin (0.49-fold), P-JNK (0.74-fold), and P-c-Jun (0.50-fold). Pathologically, Col6a1(-/-) mice display an impairment of nerve conduction velocity and motor coordination (P<0.05), as well as a delayed response to acute pain stimuli (P<0.001), indicating that lack of collagen VI causes functional defects of peripheral nerves. Altogether, these results indicate that collagen VI is a critical component of PNS contributing to the structural integrity and proper function of peripheral nerves. PMID:24277578

  7. Functional imaging of tumor vascular network in small animal models

    NASA Astrophysics Data System (ADS)

    Kalchenko, Vyacheslav; Madar-Balakirski, Noa; Kuznetsov, Yuri; Meglinski, Igor; Harmelin, Alon

    2011-07-01

    In current report we present synchronized in vivo imaging of tumor vascular network and tumor microenvironment obtained by combined use of Dynamic Light Scattering Imaging, Spectrally Enhanced Microscopy, and Fluorescence Intravital Microscopy. Dynamic Light Scattering Imaging is used for functional imaging of the vascular network and blood microcirculation. Spectrally Enhanced Microscopy provides information regarding blood vessel topography. Fluorescence Intravital Microscopy is used for imaging of tumor microvasculature and tumor microenvironment. These well known modalities have been comprehensively validated in the past and are widely used in various bio-medical applications. As shown here, their combined application has great potential for studies of vascular biology. This multi-modal non-invasive diagnostic technique expands our current capacity to investigate blood microcirculation and tumor angiogenesis in vivo, thereby contributing to the development of cancer research and treatment.

  8. Vascular Tree Reconstruction by Minimizing A Physiological Functional Cost

    PubMed Central

    Jiang, Yifeng; Zhuang, Zhenwu; Sinusas, Albert J.; Papademetris, Xenophon

    2011-01-01

    The reconstruction of complete vascular trees from medical images has many important applications. Although vessel detection has been extensively investigated, little work has been done on how connect the results to reconstruct the full trees. In this paper, we propose a novel theoretical framework for automatic vessel connection, where the automation is achieved by leveraging constraints from the physiological properties of the vascular trees. In particular, a physiological functional cost for the whole vascular tree is derived and an efficient algorithm is developed to minimize it. The method is generic and can be applied to different vessel detection/segmentation results, e.g. the classic rigid detection method as adopted in this paper. We demonstrate the effectiveness of this method on both 2D and 3D data. PMID:21755061

  9. A Novel Protective Function of 5-Methoxytryptophan in Vascular Injury

    PubMed Central

    Ho, Yen-Chun; Wu, Meng-Ling; Su, Chen-Hsuan; Chen, Chung-Huang; Ho, Hua-Hui; Lee, Guan-Lin; Lin, Wei-Shiang; Lin, Wen-Yu; Hsu, Yu-Juei; Kuo, Cheng-Chin; Wu, Kenneth K.; Yet, Shaw-Fang

    2016-01-01

    5-Methoxytryptophan (5-MTP), a 5-methoxyindole metabolite of tryptophan metabolism, was recently shown to suppress inflammatory mediator-induced cancer cell proliferation and migration. However, the role of 5-MTP in vascular disease is unknown. In this study, we investigated whether 5-MTP protects against vascular remodeling following arterial injury. Measurements of serum 5-MTP levels in healthy subjects and patients with coronary artery disease (CAD) showed that serum 5-MTP concentrations were inversely correlated with CAD. To test the role of 5-MTP in occlusive vascular disease, we subjected mice to a carotid artery ligation model of neointima formation and treated mice with vehicle or 5-MTP. Compared with vehicle-treated mice, 5-MTP significantly reduced intimal thickening by 40% 4 weeks after ligation. BrdU incorporation assays revealed that 5-MTP significantly reduced VSMC proliferation both in vivo and in vitro. Furthermore, 5-MTP reduced endothelial loss and detachment, ICAM-1 and VCAM-1 expressions, and inflammatory cell infiltration in the ligated arterial wall, suggesting attenuation of endothelial dysfunction. Signaling pathway analysis indicated that 5-MTP mediated its effects predominantly via suppressing p38 MAPK signaling in endothelial and VSMCs. Our data demonstrate a novel vascular protective function of 5-MTP against arterial injury-induced intimal hyperplasia. 5-MTP might be a therapeutic target for preventing and/or treating vascular remodeling. PMID:27146795

  10. A Novel Protective Function of 5-Methoxytryptophan in Vascular Injury.

    PubMed

    Ho, Yen-Chun; Wu, Meng-Ling; Su, Chen-Hsuan; Chen, Chung-Huang; Ho, Hua-Hui; Lee, Guan-Lin; Lin, Wei-Shiang; Lin, Wen-Yu; Hsu, Yu-Juei; Kuo, Cheng-Chin; Wu, Kenneth K; Yet, Shaw-Fang

    2016-01-01

    5-Methoxytryptophan (5-MTP), a 5-methoxyindole metabolite of tryptophan metabolism, was recently shown to suppress inflammatory mediator-induced cancer cell proliferation and migration. However, the role of 5-MTP in vascular disease is unknown. In this study, we investigated whether 5-MTP protects against vascular remodeling following arterial injury. Measurements of serum 5-MTP levels in healthy subjects and patients with coronary artery disease (CAD) showed that serum 5-MTP concentrations were inversely correlated with CAD. To test the role of 5-MTP in occlusive vascular disease, we subjected mice to a carotid artery ligation model of neointima formation and treated mice with vehicle or 5-MTP. Compared with vehicle-treated mice, 5-MTP significantly reduced intimal thickening by 40% 4 weeks after ligation. BrdU incorporation assays revealed that 5-MTP significantly reduced VSMC proliferation both in vivo and in vitro. Furthermore, 5-MTP reduced endothelial loss and detachment, ICAM-1 and VCAM-1 expressions, and inflammatory cell infiltration in the ligated arterial wall, suggesting attenuation of endothelial dysfunction. Signaling pathway analysis indicated that 5-MTP mediated its effects predominantly via suppressing p38 MAPK signaling in endothelial and VSMCs. Our data demonstrate a novel vascular protective function of 5-MTP against arterial injury-induced intimal hyperplasia. 5-MTP might be a therapeutic target for preventing and/or treating vascular remodeling. PMID:27146795

  11. Distribution and function of peripheral alpha-adrenoceptors in the cardiovascular system.

    PubMed

    Ruffolo, R R

    1985-05-01

    alpha-Adrenoceptors may be subdivided based on their anatomical distribution within the synapse. Presynaptic alpha-adrenoceptors are generally of the alpha 2-subtype and modulate neurotransmitter liberation via a negative feedback mechanism. Postsynaptic alpha-adrenoceptors are usually of the alpha 1-subtype and mediate the response of the effector organ. Although this "anatomical" subclassification is generally applicable, many exceptions exist. A more useful classification of alpha-adrenoceptor subtypes is based on a pharmacological characterization in which selective agonists and antagonists are used. Peripheral alpha-adrenoceptors are critical in the regulation of the cardiovascular system. Postsynaptic alpha-adrenoceptors in arteries and veins represent a mixed population of alpha 1/alpha 2-adrenoceptors, with both subtypes mediating vasoconstriction. In the peripheral arterial circulation, postsynaptic vascular alpha 1-adrenoceptors are found in the adrenergic neuroeffector junction, whereas postsynaptic vascular alpha 2-adrenoceptors are located extrajunctionally. In the venous circulation, it appears that alpha 2-adrenoceptors may be predominantly junctional, whereas alpha 1-adrenoceptors may be predominantly extrajunctional. It has been proposed that junctional alpha-adrenoceptors will respond predominantly to norepinephrine liberated from sympathetic neurons, whereas extrajunctional alpha-adrenoceptors likely respond to circulating catecholamines. The functional role of extrajunctional alpha-adrenoceptors may be more important in disease states such as hypertension and congestive heart failure where circulating levels of catecholamines may be high and contribute to the maintenance of elevated vascular resistance. alpha 2-Adrenoceptors are also associated with the intima and may play a role in the release of an endogenous relaxing factor from the endothelium.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2989947

  12. Mortality After Nontraumatic Major Amputation Among Patients With Diabetes and Peripheral Vascular Disease: A Systematic Review.

    PubMed

    Thorud, Jakob C; Plemmons, Britton; Buckley, Clifford J; Shibuya, Naohiro; Jupiter, Daniel C

    2016-01-01

    High mortality rates have been reported after major amputations of a lower limb secondary to diabetes and peripheral vascular disease. However, the mortality rates have varied across studies. A systematic review of the 5-year mortality after nontraumatic major amputations of the lower extremity was conducted. A data search was performed of Medline using OVID, CINHAL, and Cochrane, 365 abstracts were screened, and 79 full text articles were assessed for eligibility. After review, 31 studies met the inclusion and exclusion criteria. Overall, the 5-year mortality rate was very high among patients with any amputation (major and minor combined), ranging from 53% to 100%, and in patients with major amputations, ranging from 52% to 80%. Mortality after below-the-knee amputation ranged from 40% to 82% and after above-the-knee amputation from 40% to 90%. The risk factors for increased mortality included age, renal disease, proximal amputation, and peripheral vascular disease. Although our previous systematic review of the 5-year mortality after ulceration had much lower rates of death, additional studies are warranted to determine whether amputation hastens death or is a marker for underlying disease severity. PMID:26898398

  13. The plant vascular system: evolution, development and functions.

    PubMed

    Lucas, William J; Groover, Andrew; Lichtenberger, Raffael; Furuta, Kaori; Yadav, Shri-Ram; Helariutta, Ykä; He, Xin-Qiang; Fukuda, Hiroo; Kang, Julie; Brady, Siobhan M; Patrick, John W; Sperry, John; Yoshida, Akiko; López-Millán, Ana-Flor; Grusak, Michael A; Kachroo, Pradeep

    2013-04-01

    The emergence of the tracheophyte-based vascular system of land plants had major impacts on the evolution of terrestrial biology, in general, through its role in facilitating the development of plants with increased stature, photosynthetic output, and ability to colonize a greatly expanded range of environmental habitats. Recently, considerable progress has been made in terms of our understanding of the developmental and physiological programs involved in the formation and function of the plant vascular system. In this review, we first examine the evolutionary events that gave rise to the tracheophytes, followed by analysis of the genetic and hormonal networks that cooperate to orchestrate vascular development in the gymnosperms and angiosperms. The two essential functions performed by the vascular system, namely the delivery of resources (water, essential mineral nutrients, sugars and amino acids) to the various plant organs and provision of mechanical support are next discussed. Here, we focus on critical questions relating to structural and physiological properties controlling the delivery of material through the xylem and phloem. Recent discoveries into the role of the vascular system as an effective long-distance communication system are next assessed in terms of the coordination of developmental, physiological and defense-related processes, at the whole-plant level. A concerted effort has been made to integrate all these new findings into a comprehensive picture of the state-of-the-art in the area of plant vascular biology. Finally, areas important for future research are highlighted in terms of their likely contribution both to basic knowledge and applications to primary industry. PMID:23462277

  14. BP and Vascular Function Following Space Flight

    NASA Technical Reports Server (NTRS)

    Hatton, Daniel C.; Yue, Qi; Chapman, Justin; Xue, Hong; Dierickx, Jacqueline; Roullet, Chantal; Roullet, Jean-Baptiste; Phanouvong, Thongchanh; Watanabe, Mitsuaki; Otsuka, Keiichi; McCarron, David A.

    1997-01-01

    Blood pressure and mesenteric resistance artery function were assessed in 9-week-old spontaneously hypertensive rats following an 18 day shuttle flight on STS-80. Blood pressure was measured twice, first in conscious animals using a tail-cuff method and then while the animals were anesthetized with 2% halothane in O2. Isolated mesenteric resistance artery responses to cumulative additions of norepinephrine, acetylcholine, sodium nitroprusside, and calcium were measured within 17 hours of landing using wire myography. Blood pressure was slightly reduced in conscious animals following flight (p=0.056) but was significantly elevated (p less than.001) above vivarium control group values in anesthetized animals. Maximal contraction of mesenteric arteries to norepinephrine was attenuated in the flight animals (p less than.001)aswasrelaxationtoacetylcholine(p less than .001)andcalcium(p less than .05). There was no difference between flight and control animals in the vessel response to sodium nitroprusside (p greater than .05). The results suggest that there may have been an increase in synthesis and release of nitric oxide in the flight animals.

  15. Markers of inflammation, Vitamin E and peripheral nervous system function

    PubMed Central

    Di Iorio, Angelo; Cherubini, Antonio; Volpato, Stefano; Sparvieri, Eleonora; Lauretani, Fulvio; Franceschi, Claudio; Senin, Umberto; Abate, Giuseppe; Paganelli, Roberto; Martin, Antonio; Andres-Lacueva, Cristina; Ferrucci, Luigi

    2009-01-01

    Background Aging of the peripheral nervous system is associated with several morphologic and functional changes, including a decrease of the nerve conduction velocity. There is evidence that these changes contribute to age-related-decline in muscle strength, sensory discrimination, and autonomic responses. The aim of this study was to characterize the decline in nerve conduction velocity in the peripheral nervous system over the aging process and to identify factors that, independent of age, affect nerve conduction velocity. Methods We measured motor nerve conduction velocity of the right superficial peroneal nerve using a standard neurophysiologic technique in a population-based sample of subjects aged between 20 and 103 years old enrolled in the InCHIANTI study. Results Average conduction velocities in the peripheral nerve decreased linearly with age in both sexes. We found that diabetes, cognitive impairment, uric acid, sIL-6R and α-tocopherol were significant predictors of nerve conduction velocity independently of the potential confounding effect of age, sex, sex × age interaction term, height, lymphocytes, neutrophils number, α1 and α2-globulin serum protein. Conclusion Our findings are consistent with the hypothesis that inflammation and inadequate antioxidant defenses are associated with accelerated decline of nerve conduction velocity over the aging process. PMID:16112778

  16. Enzymatic regulation of functional vascular networks using gelatin hydrogels

    PubMed Central

    Chuang, Chia-Hui; Lin, Ruei-Zeng; Tien, Han-Wen; Chu, Ya-Chun; Li, Yen-Cheng; Melero-Martin, Juan M.; Chen, Ying-Chieh

    2015-01-01

    To manufacture tissue engineering-based functional tissues, scaffold materials that can be sufficiently vascularized to mimic the functionality and complexity of native tissues are needed. Currently, vascular network bioengineering is largely carried out using natural hydrogels as embedding scaffolds, but most natural hydrogels have poor mechanical stability and durability, factors that critically limit their widespread use. In this study, we examined the suitability of gelatin-phenolic hydroxyl (gelatin-Ph) hydrogels that can be enzymatically crosslinked, allowing tuning of the storage modulus and the proteolytic degradation rate, for use as injectable hydrogels to support the human progenitor cell-based formation of a stable and mature vascular network. Porcine gelatin-Ph hydrogels were found to be cytocompatible with human blood-derived endothelial colony-forming cells and white adipose tissue-derived mesenchymal stem cells, resulting in >87% viability, and cell proliferation and spreading could be modulated by using hydrogels with different proteolytic degradability and stiffness. In addition, gelatin was extracted from mouse dermis and murine gelatin-Ph hydrogels were prepared. Importantly, implantation of human cell-laden porcine or murine gelatin-Ph hydrogels into immunodeficient mice resulted in the rapid formation of functional anastomoses between the bioengineered human vascular network and the mouse vasculature. Furthermore, the degree of enzymatic crosslinking of the gelatin-Ph hydrogels could be used to modulate cell behavior and the extent of vascular network formation in vivo. Our report details a technique for the synthesis of gelatin-Ph hydrogels from allogeneic or xenogeneic dermal skin and suggests that these hydrogels can be used for biomedical applications that require the formation of microvascular networks, including the development of complex engineered tissues. PMID:25749296

  17. Quantitative objective assessment of peripheral nociceptive C fibre function.

    PubMed Central

    Parkhouse, N; Le Quesne, P M

    1988-01-01

    A technique is described for the quantitative assessment of peripheral nociceptive C fibre function by measurement of the axon reflex flare. Acetylcholine, introduced by electrophoresis, is used to stimulate a ring of nociceptive C fibre endings at the centre of which the increase in blood flow is measured with a laser Doppler flowmeter. This flare (neurogenic vasodilatation) has been compared with mechanically or chemically stimulated non-neurogenic cutaneous vasodilation. The flare is abolished by local anaesthetic and is absent in denervated skin. The flare has been measured on the sole of the foot of 96 healthy subjects; its size decreases with age in males, but not in females. Images PMID:3351528

  18. Arterial structure and function in vascular ageing: are you as old as your arteries?

    PubMed

    Thijssen, Dick H J; Carter, Sophie E; Green, Daniel J

    2016-04-15

    Advancing age may be the most potent independent predictor of future cardiovascular events, a relationship that is not fully explained by time-related changes in traditional cardiovascular risk factors. Since some arteries exhibit differential susceptibility to atherosclerosis, generalisations regarding the impact of ageing in humans may be overly simplistic, whereas in vivo assessment of arterial function and health provide direct insight. Coronary and peripheral (conduit, resistance and skin) arteries demonstrate a gradual, age-related impairment in vascular function that is likely to be related to a reduction in endothelium-derived nitric oxide bioavailability and/or increased production of vasoconstrictors (e.g. endothelin-1). Increased exposure and impaired ability for defence mechanisms to resist oxidative stress and inflammation, but also cellular senescence processes, may contribute to age-related changes in vascular function and health. Arteries also undergo structural changes as they age. Gradual thickening of the arterial wall, changes in wall content (i.e. less elastin, advanced glycation end-products) and increase in conduit artery diameter are observed with older age and occur similarly in central and peripheral arteries. These changes in structure have important interactive effects on artery function, with increases in small and large arterial stiffness representing a characteristic change with older age. Importantly, direct measures of arterial function and structure predict future cardiovascular events, independent of age or other cardiovascular risk factors. Taken together, and given the differential susceptibility of arteries to atherosclerosis in humans, direct measurement of arterial function and health may help to distinguish between biological and chronological age-related change in arterial health in humans. PMID:26140618

  19. Gender Differences in Bed Rest: Preliminary Analysis of Vascular Function

    NASA Technical Reports Server (NTRS)

    Platts, Steven H.; Stenger, Michael B.; Martin, David S.; Freeman-Perez, Sondra A.; Phillips, Tiffany; Ribeiro, L. Christine

    2008-01-01

    Orthostatic intolerance is a recognized consequence of spaceflight. Numerous studies have shown that women are more susceptible to orthostatic intolerance following spaceflight as well as bed rest, the most commonly used ground-based analog for spaceflight. One of the possible mechanisms proposed to account for this is a difference in vascular responsiveness between genders. We hypothesized that women and men would have differing vascular responses to 90 days of 6-degree head down tilt bed rest. Additionally, we hypothesized that vessels in the upper and lower body would respond differently, as has been shown in the animal literature. Thirteen subjects were placed in bedrest for 90 days (8 men, 5 women) at the Flight Analogs Unit, UTMB. Direct arterial and venous measurements were made with ultrasound to evaluate changes in vascular structure and function. Arterial function was assessed, in the arm and leg, during a reactive hyperemia protocol and during sublingual nitroglycerin administration to gauge the contributions of endothelial dependent and independent dilator function respectively. Venous function was assessed in dorsal hand and foot veins during the administration of pharmaceuticals to assess constrictor and dilator function. Both gender and day effects are seen in arterial dilator function to reactive hyperemia, but none are seen with nitroglycerin. There are also differences in the wall thickness in the arm vs the leg during bed rest, which return toward pre-bed rest levels by day 90. More subjects are required, especially females as there is not sufficient power to properly analyze venous function. Day 90 data are most underpowered.

  20. Impaired Right Ventricular-Pulmonary Vascular Function in Myeloproliferative Neoplasms

    PubMed Central

    Roach, Emir C.; Park, Margaret M.; Tang, W.H. Wilson; Thomas, James D.; Asosingh, Kewal; Kalaycio, Matt; Erzurum, Serpil C.; Farha, Samar

    2014-01-01

    Background Increased bone marrow hemangioblast numbers, alterations in erythroid/myeloid lineages, increased reticulin, and greater circulating bone marrow progenitor cells are present in patients with pulmonary arterial hypertension (PAH). The data suggest that myeloid progenitors contribute to the pathogenesis of PAH, but there is little data on prevalence of pulmonary vascular disease among different forms of myeloid diseases. We hypothesized that there would be a higher prevalence of pulmonary vascular disease in myeloproliferative neoplasms that have high circulating progenitor cells, such as myelofibrosis and chronic myelogenous leukemia (CML), as compared to those with low circulating progenitors, as in aplastic anemia. Methods Patients with myelofibrosis, CML and aplastic anemia who underwent echocardiographic evaluation of cardiac function in preparation for bone marrow transplantation at the Cleveland Clinic between 1997–2012 were identified using electronic medical records for demographic data, blood cell counts, and pulmonary function tests. All echocardiograms were uniformly analyzed in a blinded fashion by an advanced sonographer and cardiologist for measures of right and left ventricular function and estimation of pulmonary vascular disease. Results Gender and race distribution between disease groups were similar. Myelofibrosis [N=19] and aplastic anemia [N=30] had increased right ventricle (RV) wall thickness compared to CML [N=82] [RV Thickness (cm): aplastic anemia 0.7 ± 0.1, CML 0.5 ± 0.1 and myelofibrosis 0.7 ± 0.1; p = 0.02]. Patients with myelofibrosis had higher levels of estimated RV systolic pressure as compared to the other groups [RVSP (mmHg): aplastic anemia 29.9 ± 1.5, CML 26.2 ± 1.1 and myelofibrosis 36.7 ± 3.7; p < 0.01]. Conclusion The findings suggest an important role for myeloid progenitors in maintenance of pulmonary-vascular health, in which abnormal myeloproliferative progenitors are associated with right ventricle

  1. Microsecond-pulsed dielectric barrier discharge plasma stimulation of tissue macrophages for treatment of peripheral vascular disease

    SciTech Connect

    Miller, V. Lin, A.; Brettschneider, J.; Fridman, G.; Fridman, A.; Kako, F.; Gabunia, K.; Kelemen, S.; Autieri, M.

    2015-12-15

    Angiogenesis is the formation of new blood vessels from pre-existing vessels and normally occurs during the process of inflammatory reactions, wound healing, tissue repair, and restoration of blood flow after injury or insult. Stimulation of angiogenesis is a promising and an important step in the treatment of peripheral artery disease. Reactive oxygen species have been shown to be involved in stimulation of this process. For this reason, we have developed and validated a non-equilibrium atmospheric temperature and pressure short-pulsed dielectric barrier discharge plasma system, which can non-destructively generate reactive oxygen species and other active species at the surface of the tissue being treated. We show that this plasma treatment stimulates the production of vascular endothelial growth factor, matrix metalloproteinase-9, and CXCL 1 that in turn induces angiogenesis in mouse aortic rings in vitro. This effect may be mediated by the direct effect of plasma generated reactive oxygen species on tissue.

  2. Microsecond-pulsed dielectric barrier discharge plasma stimulation of tissue macrophages for treatment of peripheral vascular disease

    NASA Astrophysics Data System (ADS)

    Miller, V.; Lin, A.; Kako, F.; Gabunia, K.; Kelemen, S.; Brettschneider, J.; Fridman, G.; Fridman, A.; Autieri, M.

    2015-12-01

    Angiogenesis is the formation of new blood vessels from pre-existing vessels and normally occurs during the process of inflammatory reactions, wound healing, tissue repair, and restoration of blood flow after injury or insult. Stimulation of angiogenesis is a promising and an important step in the treatment of peripheral artery disease. Reactive oxygen species have been shown to be involved in stimulation of this process. For this reason, we have developed and validated a non-equilibrium atmospheric temperature and pressure short-pulsed dielectric barrier discharge plasma system, which can non-destructively generate reactive oxygen species and other active species at the surface of the tissue being treated. We show that this plasma treatment stimulates the production of vascular endothelial growth factor, matrix metalloproteinase-9, and CXCL 1 that in turn induces angiogenesis in mouse aortic rings in vitro. This effect may be mediated by the direct effect of plasma generated reactive oxygen species on tissue.

  3. Value of a 24-hour image (four-phase bone scan) in assessing osteomyelitis in patients with peripheral vascular disease

    SciTech Connect

    Alazraki, N.; Dries, D.; Datz, F.; Lawrence, P.; Greenberg, E.; Taylor, A. Jr.

    1985-07-01

    The delayed images of the four-phase /sup 99m/Tc phosphonate bone scan are compared with the delayed images of the three-phase study in patients with diabetes mellitus and/or peripheral vascular disease and suspected osteomyelitis. Three-phase bone imaging includes an immediate postinjection radionuclide angiogram, a blood-pool image, and delayed static images to 7 hr. The four-phase study adds a 24-hr static image. The scan is positive for osteomyelitis if images show progressively increasing lesion to background activity ratios over time. The results of analyzing 21 three- and four-phase bone scans in 17 patients were correlated with clinical course, cultures, and/or x-rays, gallium scans, and CT scans. The accuracy of four-phase bone imaging for diagnosing osteomyelitis was 85%; for three phase, 80%. Sensitivity for four phase was 80%; specificity was 87%. Sensitivity for three phase was 100%; specificity was 73%.

  4. Percutaneous Treatment of Peripheral Vascular Malformations in Children: Long-Term Clinical Outcome

    SciTech Connect

    Linden, Edwin van der; Otoide-Vree, Marleen; Pattynama, Peter M. T.

    2012-04-15

    Purpose: This study was designed to assess the rate of complications and clinical failure at 3 and 12 months after percutaneous treatment of vascular malformations in children. Furthermore, we describe patient satisfaction of treatment results during 5 years of follow-up. Methods: In a retrospective cohort study, we evaluated 26 patients younger than aged 19 years who were treated for symptomatic vascular malformations. Data on treatment outcomes and patient satisfactions were obtained with a precoded structured questionnaire. Patient files and imaging data were retrieved to obtain information regarding the vascular malformations and treatment. Clinical success was defined as disappearance or partial improvement of the complaints. Patient satisfaction was declared whenever patients answered in the questionnaire that they were satisfied with the treatment results. Results: Of 26 eligible patients, we included 23 (88%). The mean follow-up was 36 (range, 15-127) months. Posttreatment, 87% (20/23; 95% confidence interval (CI), 66-97%) of patients reported clinical success at 3 months. At 1, 2, 3, 4, and 5 years of follow-up this percentage was 74%, 59%, 59%, 59%, and 59%, respectively. Eleven (48%, 95% CI 27-69%) patients had experienced complications and 22% (95% CI 7-44%) had major complications, of which 5 had required additional treatment. In all, 83% (19/23) of the patients reported satisfaction with the treatment. Conclusions: Percutaneous treatment of vascular malformations improved clinical symptoms in 87% of the patients at 3 months and were sustainable for half of all patients during a 5-year follow-up period. However, major complications were seen in 22%.

  5. Non-invasive and quantitative evaluation of peripheral vascular resistances in rats by combined NMR measurements of perfusion and blood pressure using ASL and dynamic angiography.

    PubMed

    Ménard, Jacques C; Giacomini, Eric; Baligand, Céline; Fromes, Yves; Carlier, Pierre G

    2010-02-01

    The in vivo determination of peripheral vascular resistances (VR) is crucial for the assessment of arteriolar function. It requires simultaneous determination of organ perfusion (F) and arterial blood pressure (BP). A fully non-invasive method was developed to measure systolic and diastolic BP in the caudal artery of rats based on dynamic NMR angiography. A good agreement was found between the NMR approach and the gold standard techniques (linear regression slope = 0.98, R(2) = 0.96). This method and the ASL-MRI measurement of skeletal muscle perfusion were combined into one single NMR experiment to quantitatively evaluate the local vascular resistances in the calf muscle of anaesthetized rats, in vivo and non-invasively 1) at rest: VR = 7.0 +/- 1.0 mmHg x min 100 g x ml(-1), F = 13 +/- 3 ml min(-1) x 100 g(-1) and mean BP (MBP) = 88 +/- 10 mmHg; 2) under vasodilator challenge (milrinone): VR = 3.7 +/- 1.1 mmHg min x 100 g ml(-1), F = 21 +/- 4 ml min(-1) x 100 g(-1) and MBP = 75 +/- 14 mmHg; 3) under vasopressor challenge (norepinephrine): VR = 9.8 +/- 1.2 mmHg min 100 g ml(-1), F = 14 +/- 3 ml min(-1) x 100 g(-1) and MBP = 137 +/- 2 mmHg. PMID:19795372

  6. Sustained release nitrite therapy results in myocardial protection in a porcine model of metabolic syndrome with peripheral vascular disease

    PubMed Central

    Bradley, Jessica M.; Islam, Kazi N.; Polhemus, David J.; Donnarumma, Erminia; Brewster, Luke P.; Tao, Ya-Xiong; Goodchild, Traci T.

    2015-01-01

    Metabolic syndrome (MetS) reduces endothelial nitric oxide (NO) bioavailability and exacerbates vascular dysfunction in patients with preexisting vascular diseases. Nitrite, a storage form of NO, can mediate vascular function during pathological conditions when endogenous NO is reduced. The aims of the present study were to characterize the effects of severe MetS and obesity on dyslipidemia, myocardial oxidative stress, and endothelial NO synthase (eNOS) regulation in the obese Ossabaw swine (OS) model and to examine the effects of a novel, sustained-release formulation of sodium nitrite (SR-nitrite) on coronary vascular reactivity and myocardial redox status in obese OS subjected to critical limb ischemia (CLI). After 6 mo of an atherogenic diet, obese OS displayed a MetS phenotype. Obese OS had decreased eNOS functionality and NO bioavailability. In addition, obese OS exhibited increased oxidative stress and a significant reduction in antioxidant enzymes. The efficacy of SR-nitrite therapy was examined in obese OS subjected to CLI. After 3 wk of treatment, SR-nitrite (80 mg·kg−1·day−1 bid po) increased myocardial nitrite levels and eNOS function. Treatment with SR-nitrite reduced myocardial oxidative stress while increasing myocardial antioxidant capacity. Ex vivo assessment of vascular reactivity of left anterior descending coronary artery segments demonstrated marked improvement in vasoreactivity to sodium nitroprusside but not to substance P and bradykinin in SR-nitrite-treated animals compared with placebo-treated animals. In conclusion, in a clinically relevant, large-animal model of MetS and CLI, treatment with SR-nitrite enhanced myocardial NO bioavailability, attenuated oxidative stress, and improved ex vivo coronary artery vasorelaxation. PMID:25957218

  7. Biosynthesis and Functional Significance of Peripheral Node Addressin in Cancer-Associated TLO.

    PubMed

    Weinstein, Aliyah M; Storkus, Walter J

    2016-01-01

    Peripheral node addressin (PNAd) marks high endothelial venules (HEV), which are crucial for the recruitment of lymphocytes into lymphoid organs in non-mucosal tissue sites. PNAd is a sulfated and fucosylated glycoprotein recognized by the prototypic monoclonal antibody, MECA-79. PNAd is the ligand for L-selectin, which is expressed on the surface of naive and central memory T cells, where it mediates leukocyte rolling on vascular endothelial surfaces. Although PNAd was first identified in the HEV of peripheral lymph nodes, recent work suggests a critical role for PNAd in the context of chronic inflammatory diseases, where it can be used as a marker for the formation of tertiary lymphoid organs (TLOs). TLO form in tissues impacted by sustained inflammation, such as the tumor microenvironment where they function as local sites of adaptive immune cell priming. This allows for specific B- and T-cell responses to be initiated or reactivated in inflamed tissues without dependency on secondary lymphoid organs. Recent studies of cancer in mice and humans have identified PNAd as a biomarker of improved disease prognosis. Blockade of PNAd or its ligand, L-selectin, can abrogate protective antitumor immunity in murine models. This review examines pathways regulating PNAd biosynthesis by the endothelial cells integral to HEV and the formation and maintenance of lymphoid structures throughout the body, particularly in the setting of cancer. PMID:27555845

  8. Biosynthesis and Functional Significance of Peripheral Node Addressin in Cancer-Associated TLO

    PubMed Central

    Weinstein, Aliyah M.; Storkus, Walter J.

    2016-01-01

    Peripheral node addressin (PNAd) marks high endothelial venules (HEV), which are crucial for the recruitment of lymphocytes into lymphoid organs in non-mucosal tissue sites. PNAd is a sulfated and fucosylated glycoprotein recognized by the prototypic monoclonal antibody, MECA-79. PNAd is the ligand for L-selectin, which is expressed on the surface of naive and central memory T cells, where it mediates leukocyte rolling on vascular endothelial surfaces. Although PNAd was first identified in the HEV of peripheral lymph nodes, recent work suggests a critical role for PNAd in the context of chronic inflammatory diseases, where it can be used as a marker for the formation of tertiary lymphoid organs (TLOs). TLO form in tissues impacted by sustained inflammation, such as the tumor microenvironment where they function as local sites of adaptive immune cell priming. This allows for specific B- and T-cell responses to be initiated or reactivated in inflamed tissues without dependency on secondary lymphoid organs. Recent studies of cancer in mice and humans have identified PNAd as a biomarker of improved disease prognosis. Blockade of PNAd or its ligand, L-selectin, can abrogate protective antitumor immunity in murine models. This review examines pathways regulating PNAd biosynthesis by the endothelial cells integral to HEV and the formation and maintenance of lymphoid structures throughout the body, particularly in the setting of cancer. PMID:27555845

  9. Initial experience with a novel hybrid vascular graft for peripheral artery disease.

    PubMed

    Willaert, W; Claes, K; Flamme, A; Jacobs, B

    2014-03-01

    This report describes the successful use of a new hybrid vascular graft as a conduit for above knee femoropopliteal bypass surgery. The graft consists of a proximal (heparin coated) expanded polytetrafluoroethylene section but ends distally as a nitinol reinforced selfexpandable stent that is covered and constrained, allowing a sutureless distal anastamosis. With this graft the creation of above knee bypasses in situations where lesions extend to the popliteal artery behind the knee, or in cases where the above knee popliteal artery is severely calcified is still possible. This avoids the necessity of an infragenicular bypass with potentially inferior longterm patency rates, especially when no autologous venous bypass material is available. PMID:24594800

  10. Assessment of vascular function in systemic onset juvenile idiopathic arthritis.

    PubMed

    Sozeri, Betul; Atikan, Basak Yildiz; Ozdemir, Kadriye; Mir, Sevgi

    2016-07-01

    and disease duration (p = 0.003, r = 0.45). Vascular function is impaired in patients with sJIA at a very young age. Vascular dysfunction may be partly attributed to the effects of disease-related characteristics (inflammation, disease activity, and medications). PMID:27075461

  11. A Study on the Relationship between Serum Beta 2-Microglobulin Levels, Underlying Chronic Kidney Disease, and Peripheral Arterial Disease in High-Vascular-Risk Patients

    PubMed Central

    Real de Asúa, Diego; Puchades, Ramón; García-Polo, Iluminada; Suárez, Carmen

    2012-01-01

    Background Serum beta 2-microglobulin (B2M) levels have been found to be increased in patients with peripheral arterial disease (PAD), yet it is still unknown whether B2M correlates with PAD intensity. Objectives We aim to evaluate the correlation between B2M and the ankle-brachial index (ABI) values in high-vascular-risk patients. Methods This is a cross-sectional study of 63 high-vascular-risk patients admitted to the Cardiology Department or evaluated as outpatients in the Internal Medicine Department of our institution. Patients were classified into two groups according to their ABI: patients without PAD (n = 44, ABI values between 0.9 and 1.4) and patients with PAD (n = 19, ABI values lower than 0.9 or higher than 1.4). We performed univariate and multivariate analysis based on a multiple linear regression model. Results Serum B2M levels were higher in patients with pathological ABI values than in those without PAD (2.36 ± 1.13 vs. 1.80 ± 0.65 mg/L; P<0.05). We found no correlation between B2M and ABI in our total population (r = –0.12) or in patients with PAD (r = –0.09; NS for both comparisons). Age, gender, arterial hypertension, estimated glomerular filtration rate (eGFR), uric acid, total cholesterol, and LDL-cholesterol correlated with B2M in the univariate analysis. In the final linear regression model, eGFR, uric acid and total cholesterol correlated independently with B2M (P<0.01). Conclusion We found no correlation between B2M levels and ABI values in high-vascular-risk patients that could usefully help in the subsequent diagnosis of PAD. However, we observed a significant correlation between B2M and eGFR, even when renal function was only slightly impaired. PMID:24757603

  12. Functional role of connexins and pannexins in the interaction between vascular and nervous system.

    PubMed

    Gaete, Pablo S; Lillo, Mauricio A; Figueroa, Xavier F

    2014-10-01

    The microvascular network of the microcirculation works in tight communication with surrounding tissues to control blood supply and exchange of solutes. In cerebral circulation, microvascular endothelial cells constitute a selective permeability barrier that controls the environment of parenchymal brain tissue, which is known as the blood-brain barrier (BBB). Connexin- and pannexin-formed channels (gap junctions and hemichannels) play a central role in the coordination of endothelial and smooth muscle cell function and connexin-mediated signaling in endothelial cells is essential in the regulation of BBB permeability. Likewise, gap junction communication between astrocyte end-feet also contributes to maintain the BBB integrity, but the participation of hemichannels in this process cannot be discarded. Sympathetic and sensory perivascular nerves are also involved in the control and coordination of vascular function through the release of vasoconstrictor or vasodilator signals and by the regulation of gap junction communication in the vessel wall. Conversely, ATP release through pannexin-1-formed channels mediates the α1-adrenergic signaling. Furthermore, here we show that capsaicin-induced CGRP release from mesenteric perivascular sensory nerves induces pannexin-1-formed channel opening, which in turn leads to reduction of pannexin-1 and endothelial nitric oxide synthase (eNOS) expression along the time. Interestingly, blockade of CGRP receptors with CGRP8-37 increased eNOS expression by ∼5-fold, suggesting that capsaicin-sensitive sensory nerves are involved in the control of key signaling proteins for vascular function. In this review, we discuss the importance of connexin-based channels in the control of BBB integrity and the functional interaction of vascular connexins and pannexins with the peripheral nervous system. PMID:24446239

  13. Marvels, Mysteries, and Misconceptions of Vascular Compensation to Peripheral Artery Occlusion

    PubMed Central

    ZIEGLER, MATTHEW A.; DISTASI, MATTHEW R.; BILLS, RANDALL G.; MILLER, STEVEN J.; ALLOOSH, MOUHAMAD; MURPHY, MICHAEL P.; AKINGBA, A. GEORGE; STUREK, MICHAEL; DALSING, MICHAEL C.; UNTHANK, JOSEPH L.

    2010-01-01

    Peripheral arterial disease is a major health problem and there is a significant need to develop therapies to prevent its progression to claudication and critical limb ischemia. Promising results in rodent models of arterial occlusion have generally failed to predict clinical success and led to questions of their relevance. While sub-optimal models may have contributed to the lack of progress, we suggest that advancement has also been hindered by misconceptions of the human capacity for compensation and the specific vessels which are of primary importance. We present and summarize new and existing data from humans, Ossabaw miniature pigs, and rodents which provide compelling evidence that natural compensation to occlusion of a major artery (i) may completely restore perfusion, (ii) occurs in specific pre-existing small arteries, rather than the distal vasculature, via mechanisms involving flow-mediated dilation and remodeling (iii) is impaired by cardiovascular risk factors which suppress the flow-mediated mechanisms and (iv) can be restored by reversal of endothelial dysfunction. We propose that restoration of the capacity for flow-mediated dilation and remodeling in small arteries represents a largely unexplored potential therapeutic opportunity to enhance compensation for major arterial occlusion and prevent the progression to critical limb ischemia in the peripheral circulation. PMID:20141596

  14. Glycomimetic functionalized collagen hydrogels for peripheral nerve repair

    NASA Astrophysics Data System (ADS)

    Masand, Shirley Narain

    Despite the innate regenerative potential of the peripheral nervous system, functional recovery is often limited. The goal of this dissertation was to develop a clinically relevant biomaterial strategy to (1) encourage the regrowth of axons and (2) direct them down their appropriate motor tracts. To this end, we use peptide mimics of two glycans, polysialic acid (PSA) and an epitope first discovered on human natural killer cells (HNK-1), to functionalize type I collagen hydrogels. Previous studies have shown that these molecules, in their glycan and glycomimetic form, are associated with acceleration of neurite outgrowth, glial cell proliferation, and motoneuron targeting. In vitro, we demonstrated the retained functionality of the peptide glycomimetics after conjugation to a type I collagen backbone. While HNK-functionalized collagen increased motor neurite outgrowth, PSA-functionalized collagen encouraged motor and sensory neurite outgrowth and Schwann cell extension and proliferation. When we introduce these glycomimetic-functionalized collagen hydrogels into a critical gap femoral nerve model, we show that both PSA and HNK-functionalized hydrogels yielded a significant increase in functional recovery when compared to saline, native and scramble-coupled hydrogels. However, there was an interesting divergence in the morphological results: PSA-functionalized hydrogels increased axon count and HNK-functionalized hydrogels increased motoneuron targeting and myelination. We believed that these differences may be attributed to distinct mechanisms by which the glycomimetics impart their benefit. Interestingly, however, we found no synergistic gain in recovery with the use of our composite hydrogels which we speculated may be due to an inadequate dose of the individual glycomimetic. To address this possibility, we show that increasing the amount of functionalized peptide functionalized in our composite hydrogels led to increases in axon count and area of regeneration

  15. Maternal Copper Deficiency Perpetuates Altered Vascular Function in Sprague-Dawley Rat Offspring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little is known about the consequences of maternal Cu (Cu) deficiency on the vascular function of offspring or on perpetuation of vascular effects to a second generation. We examined vascular functional responses in mesenteric arteries from Cu-deficient Sprague-Dawley rat dams and from offspring dir...

  16. The Toll of Vascular Insufficiency: Implications for the Management of Peripheral Arterial Disease

    PubMed Central

    Xu, Jun; Sachdev, Ulka

    2016-01-01

    Peripheral artery disease (PAD) can result in limb loss within six months of diagnosis in a subset of patients who cannot undergo endovascular or surgical revascularization yet continues to maintain a marginal position in cardiovascular research. While a body of literature continues to grow describing the role of danger signaling and innate immunity in cardiac biology, the role of these pathways in the ischemic myopathy associated with PAD has not been extensively studied. The following report will review the current literature on the role of Toll-like receptor (TLR) signaling in cardiovascular biology as well as in nonischemic myopathy. While attenuation of TLR signaling has not been shown to be clinically useful in the treatment of infectious inflammation, it may show promise in the management of severe arterial insufficiency. PMID:26998496

  17. Thoracic sympathectomy for peripheral vascular disease can lead to severe bronchospasm and excessive bronchial secretions

    PubMed Central

    Goyal, Vikas Deep; Gupta, Bharti; Kumar, Sanjeev; Pal, Sanjay

    2015-01-01

    A 57-year-old male patient suffering from Buerger's disease presented with pre-gangrenous changes in right foot and ischemic symptoms in right hand. Computed tomographic angiography revealed diffuse distal disease not suitable for vascular bypass and angioplasty. Right lumbar sympathectomy was done using a retroperitoneal approach followed 1 year later by right thoracic sympathectomy using a transaxillary approach. Postoperatively, the patient had severe bronchospasm and excessive secretions in the respiratory tract resistant to theophylline and sympathomimetic group of drugs and without any clinical, laboratory and radiological evidence of infection. The patient was started on anticholinergics in anticipation that sympathectomy might have lead to unopposed cholinergic activity and the symptoms improved rapidly. The patient recovered well and was discharged on 10th post-operative day. PMID:25624604

  18. Quantitative measurement of the blood flow in peripheral vascular diseases by a new radionuclide plethysmography

    SciTech Connect

    Kawakami, K.; Mori, Y.; Mashima, Y.; Shimada, T.; Fukuoka, M.

    1985-05-01

    The purpose of the study is to introduce a new plethysmography using radionuclide (RN) for a quantitative measurement of the blood flow in the extremities following the routine RN angiography. Seventy five patients with various peripheral artery diseases have been examined. RN pletysmography was performed in the supine position 15 min. after the RN angiography using 15 mCi of Tc-99m RBC. The blood flow (F) was calculated by the equation (1) which consists of three parameters, the initial slope of the time-activity curve (dc/dt*t=0) after the venous occlusion on the thigh, changes of radio-activity (C-Co) before and after avascularization by inflation of cuff with 200 mmHg pressure at calf, and the blood volume per unit tissue volume (..beta..=Vb/V,ml/100g tissue). F (ml/min/100g) = ..beta.. (dc/dt*t=0)/C-Co. The blood flow measured simultaneously by RN plethysmography and admittance plethysmography was significantly correlated (r = 0.906,n = 16). The blood flow in 67 normal subjects was 2.78 +- 0.75 ml/min/100g. In the patients with intermittent claudication the blood flow was decreased (1.89 +- 0.75 ml/min/100g,n = 75). In the cases with poorly developed colateral circulation the blood flow markedly decreased (1.62 +- 0.29 ml/min/100g,n = 10). Increases of blood flow after exercise was small in the cases with stenosis, even in patients with collaterals. This method is very useful to evaluate quantitatively the peripheral hemodynamics following the routine RN angiographic examination.

  19. The functions of TRPP2 in the vascular system

    PubMed Central

    Du, Juan; Fu, Jie; Xia, Xian-ming; Shen, Bing

    2016-01-01

    TRPP2 (polycystin-2, PC2 or PKD2), encoded by the PKD2 gene, is a non-selective cation channel with a large single channel conductance and high Ca2+ permeability. In cell membrane, TRPP2, along with polycystin-1, TRPV4 and TRPC1, functions as a mechanotransduction channel. In the endoplasmic reticulum, TRPP2 modulates intracellular Ca2+ release associated with IP3 receptors and the ryanodine receptors. Noteworthily, TRPP2 is widely expressed in vascular endothelial and smooth muscle cells of all major vascular beds, and contributes to the regulation of vessel function. The mutation of the PKD2 gene is a major cause of autosomal dominant polycystic kidney disease (ADPKD), which is not only a common genetic disease of the kidney but also a systemic disorder associated with abnormalities in the vasculature; cardiovascular complications are the leading cause of mortality and morbidity in ADPKD patients. This review provides an overview of the current knowledge regarding the TRPP2 protein and its possible role in cardiovascular function and related diseases. PMID:26725733

  20. The functions of TRPP2 in the vascular system.

    PubMed

    Du, Juan; Fu, Jie; Xia, Xian-ming; Shen, Bing

    2016-01-01

    TRPP2 (polycystin-2, PC2 or PKD2), encoded by the PKD2 gene, is a non-selective cation channel with a large single channel conductance and high Ca(2+) permeability. In cell membrane, TRPP2, along with polycystin-1, TRPV4 and TRPC1, functions as a mechanotransduction channel. In the endoplasmic reticulum, TRPP2 modulates intracellular Ca(2+) release associated with IP3 receptors and the ryanodine receptors. Noteworthily, TRPP2 is widely expressed in vascular endothelial and smooth muscle cells of all major vascular beds, and contributes to the regulation of vessel function. The mutation of the PKD2 gene is a major cause of autosomal dominant polycystic kidney disease (ADPKD), which is not only a common genetic disease of the kidney but also a systemic disorder associated with abnormalities in the vasculature; cardiovascular complications are the leading cause of mortality and morbidity in ADPKD patients. This review provides an overview of the current knowledge regarding the TRPP2 protein and its possible role in cardiovascular function and related diseases. PMID:26725733

  1. Melamine Impairs Renal and Vascular Function in Rats.

    PubMed

    Tian, Xiao Yu; Wong, Wing Tak; Lau, Chi Wai; Wang, Yi-Xiang; Cheang, Wai San; Liu, Jian; Lu, Ye; Huang, Huihui; Xia, Yin; Chen, Zhen Yu; Mok, Chuen-Shing; Lau, Chau-Ming; Huang, Yu

    2016-01-01

    Melamine incident, linked to nephrotoxicity and kidney stone in infants previously exposed to melamine-contaminated milk products, was unprecedentedly grave in China in 2008 as little was known about the mechanistic process leading to renal dysfunction in affected children. This study investigates whether neonatal ingestion of melamine leads to renal and vascular dysfunction in adulthood; and whether ingestion of melamine in pregnant rats leads to renal dysfunction in their offspring. A combination of approaches employed includes functional studies in rat renal arteries, renal blood flow measurement by functional magnetic resonance imaging, assay for pro-inflammatory and fibrotic biomarkers, immunohistochemistry, and detection of plasma and renal melamine. We provide mechanistic evidence showing for the first time that melamine reduces renal blood flow and impairs renal and vascular function associated with overexpression of inflammatory markers, transforming growth factor-β1, bone morphogenic protein 4 and cyclooxygenase-2 in kidney and renal vasculature. Melamine also induces renal inflammation and fibrosis. More importantly, melamine causes nephropathies in offsprings from pregnant rat exposed to melamine during pregnancy, as well as in neonatal rat exposed to melamine afterbirth, thus supporting the clinical observations of kidney stone and acute renal failure in infants consuming melamine-contaminated milk products. PMID:27324576

  2. Melamine Impairs Renal and Vascular Function in Rats

    PubMed Central

    Tian, Xiao Yu; Wong, Wing Tak; Lau, Chi Wai; Wang, Yi-Xiang; Cheang, Wai San; Liu, Jian; Lu, Ye; Huang, Huihui; Xia, Yin; Chen, Zhen Yu; Mok, Chuen-Shing; Lau, Chau-Ming; Huang, Yu

    2016-01-01

    Melamine incident, linked to nephrotoxicity and kidney stone in infants previously exposed to melamine-contaminated milk products, was unprecedentedly grave in China in 2008 as little was known about the mechanistic process leading to renal dysfunction in affected children. This study investigates whether neonatal ingestion of melamine leads to renal and vascular dysfunction in adulthood; and whether ingestion of melamine in pregnant rats leads to renal dysfunction in their offspring. A combination of approaches employed includes functional studies in rat renal arteries, renal blood flow measurement by functional magnetic resonance imaging, assay for pro-inflammatory and fibrotic biomarkers, immunohistochemistry, and detection of plasma and renal melamine. We provide mechanistic evidence showing for the first time that melamine reduces renal blood flow and impairs renal and vascular function associated with overexpression of inflammatory markers, transforming growth factor-β1, bone morphogenic protein 4 and cyclooxygenase-2 in kidney and renal vasculature. Melamine also induces renal inflammation and fibrosis. More importantly, melamine causes nephropathies in offsprings from pregnant rat exposed to melamine during pregnancy, as well as in neonatal rat exposed to melamine afterbirth, thus supporting the clinical observations of kidney stone and acute renal failure in infants consuming melamine-contaminated milk products. PMID:27324576

  3. Vascular function and brain-derived neurotrophic factor: The functional capacity factor.

    PubMed

    Alomari, Mahmoud A; Khabour, Omar F; Maikano, Abubakar; Alawneh, Khaldoon

    2015-12-01

    Brain-derived neurotrophic factor (BDNF) is essential for neurocognitive function. This study aims at establishing a plausible link between level of serum BDNF, functional capacity (FC), and vascular function in 181 young (age 25.5±9.1 years old), apparently healthy adults. Fasting blood samples were drawn from participants' antecubital veins into plain glass tubes while they were in a sitting position to evaluate serum BDNF using enzyme-linked immunosorbent assay (ELISA). Mercury-in-silastic strain-gauge plethysmography was used to determine arterial function indices, blood flow and vascular resistance at rest and following 5 minutes of arterial ischemia. The 6-minute walk distance (6MWD) test was used to determine FC, according to the American Thoracic Society Committee on Proficiency Standards for Clinical Pulmonary Function Laboratories guidelines. It was conducted in an enclosed corridor on a flat surface with a circular track 33 meters long. The walking course was demarcated with bright colored cones. The 6MWD correlated with BDNF (r=0.3, p=0.000), as well as with forearm blood inflow (r=0.5, p=0.000) and vascular resistance (r = -0.4, p=0.000). Subsequent comparison showed that BDNF and blood inflow were greater (p<0.05) while vascular resistance was less (p<0.05) in participants who achieved a longer 6MWD. Similarly, BDNF correlated with forearm blood inflow (r=0.4, p=0.000) and vascular resistance (r = -0.4, p=0.000). Subsequent comparison showed improved vascular function (p<0.05) in the participants with greater BDNF. In conclusion, these findings might suggest that improved vascular function in individuals with greater FC is mediated, at least partially, by an enhanced serum BDNF level. PMID:26285588

  4. Functional Imaging of Working Memory and Peripheral Endothelial Function in Middle-Aged Adults

    ERIC Educational Resources Information Center

    Gonzales, Mitzi M.; Tarumi, Takashi; Tanaka, Hirofumi; Sugawara, Jun; Swann-Sternberg, Tali; Goudarzi, Katayoon; Haley, Andreana P.

    2010-01-01

    The current study examined the relationship between a prognostic indicator of vascular health, flow-mediated dilation (FMD), and working memory-related brain activation in healthy middle-aged adults. Forty-two participants underwent functional magnetic resonance imaging while completing a 2-Back working memory task. Brachial artery…

  5. Results of a Peripheral Cutting Balloon Prospective Multicenter European Registry in Hemodialysis Vascular Access

    SciTech Connect

    Peregrin, Jan H. Rocek, Miloslav

    2007-04-15

    Purpose. To report initial experience with the Peripheral Cutting Balloon (PCB) in treatment of failing hemodialysis shunts. Methods. A total of 190 patients (95 men, 95 women; average age 64.4 {+-} 11.9 years, range 32-87 years) who were treated with the PCB for pressure-resistant stenosis, restenosis or failed percutaneous transluminal angioplasty (PTA) in the venous limb of an arteriovenous shunt were followed in seven European centers using a simple registry. The group consisted of 109 de novo lesions (57%) and 79 restenotic lesions (43%). Results. Technical success was achieved in 88.9% of cases. Primary patency was as follows (the results for whole group and simultaneous results for de novo lesions and restenoses are presented): 1 month (140 patients followed): 94%, 98%, and 93%; 3 months (116 patients followed): 93%, 98%, and 92%; 6 months (40 patients followed): 85%, 92%, and 79%; 12 months (27 patients followed): 74%, 87%, and 48%. No complication occurred. Patients experienced an equal or lower level of pain during the procedure compared with conventional PTA. Conclusion. The PCB proved to be successful in dilating pressure-resistant stenoses. We cannot conclude whether PCB angioplasty can lower the restenosis rate in hemodialysis access lesions, but the long-term patency for de novo lesions is high. A further randomized study is advisable.

  6. Load dependence of changes in forearm and peripheral vascular resistance after acute leg exercise in man.

    PubMed

    Piepoli, M; Isea, J E; Pannarale, G; Adamopoulos, S; Sleight, P; Coats, A J

    1994-07-15

    1. It is known that acute exercise is often followed by a reduction in arterial blood pressure. Little is known about the time course of the recovery of the blood pressure or the influence of the intensity of the exercise on this response. Controversy exists, in particular, concerning the changes in peripheral resistance that occur during this period. 2. Eight normal volunteers performed, in random order on separate days, voluntary upright bicycle exercise of three different intensities (maximal, moderate and minimal load) and, on another day, a control period of sitting on a bicycle. They were monitored for 60 min after each test. 3. Diastolic pressure fell after maximal exercise at 5 min (-15.45 mmHg) and 60 min (-9.45 mmHg), compared with the control day. Systolic and mean pressure also fell (non-significantly) after 45 min; heart rate was significantly elevated for the whole hour of recovery (at 60 min, +7.23 beats min-1). No changes in post-exercise blood pressure and heart rate were observed on the days of moderate and minimal exercises. 4. An increase in cardiac index was observed after maximal exercise compared with control (at 60 min, 2.6 +/- 0.3 vs. 1.9 +/- 0.2 l min-1 m-2). This was entirely accounted for by the persistent increase in heart rate, with no significant alteration in stroke volume after exercise on any day.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7965851

  7. Short-Term Exposure to Air Pollution and Digital Vascular Function

    PubMed Central

    Ljungman, Petter L.; Wilker, Elissa H.; Rice, Mary B.; Schwartz, Joel; Gold, Diane R.; Koutrakis, Petros; Vita, Joseph A.; Mitchell, Gary F.; Vasan, Ramachandran S.; Benjamin, Emelia J.; Mittleman, Murray A.; Hamburg, Naomi M.

    2014-01-01

    We investigated associations between ambient air pollution and microvessel function measured by peripheral arterial tonometry between 2003 and 2008 in the Framingham Heart Study Offspring and Third Generation Cohorts. We measured particulate matter with aerodynamic diameter ≤2.5 µm (PM2.5), black carbon, sulfates, particle number, nitrogen oxides, and ozone by using fixed monitors, and we determined moving averages for 1–7 days preceding vascular testing. We examined associations between these exposures and hyperemic response to ischemia and baseline pulse amplitude, a measure of arterial tone (n = 2,369). Higher short-term exposure to air pollutants, including PM2.5, black carbon, and particle number was associated with higher baseline pulse amplitude. For example, higher 3-day average PM2.5 exposure was associated with 6.3% higher baseline pulse amplitude (95% confidence interval: 2.0, 10.9). However, there were no consistent associations between the air pollution exposures assessed and hyperemic response. Our findings in a community-based sample exposed to relatively low pollution levels suggest that short-term exposure to ambient particulate pollution is not associated with vasodilator response, but that particulate air pollution is associated with baseline pulse amplitude, suggesting potentially adverse alterations in baseline vascular tone or compliance. PMID:25100647

  8. Cytolytic effector function is present in resting peripheral T lymphocytes.

    PubMed

    Geisberg, M; Dupont, B

    1992-11-01

    Antigen-specific cytotoxic killer lymphocytes (CTLs) represent one of the major effector functions of the immune system. It is well established that, as a consequence of TCR recognition of the antigen-bearing target cell, resting T lymphocytes develop into fully active antigen-specific CTLs. In contrast, natural killer (NK) cells are immediately lytic upon contact with an appropriate target cell. The lytic machinery of CTLs and NK cells is thought to include the contents of their cytoplasmic granules, in particular the pore-forming protein perforin. Here we report direct cytolytic activity by resting peripheral CD3+CD8+ T cells as a result of TCR-CD3 binding to the target cell; the murine OKT3 hybridoma (anti-human CD3) was used as a target. The cytotoxicity was more pronounced in the CD8+CD45RO+ population, which contains 'memory' T cells, than in the reciprocal CD8+CD45RA+ subset; CD8+CD4- mature thymocytes were non-cytotoxic. The cytolytic potential of these populations correlated with the presence or absence of perforin. The results demonstrate that the cytolytic machinery of T cells develops post-thymically and can be immediately triggered by TCR-CD3 stimulation. PMID:1472478

  9. Silymarin improves vascular function of aged ovariectomized rats.

    PubMed

    Demirci, Buket; Dost, Turhan; Gokalp, Filiz; Birincioglu, Mustafa

    2014-06-01

    Both aging and estrogen depletion lead to endothelial dysfunction, which is the main reason of many cardiovascular diseases. Previous reports have shown that cell protective effect of silymarin (SM) depends on its antioxidant and phytoestrogenic properties. We investigated the effect of SM on vascular stiffness of aged menopausal rats and the involvement of estrogenic activity in this effect. Isolated rat aortas were obtained from 22-month-old rats, after 18 months of ovariectomy (OVX) follow-up. Each ring was incubated in tissue bath either with SM (50 mg/L) and 17β-estradiol (10 μM, E2) or in the presence of SM/fulvestrant (50 mg/L, 10 μM). Endothelium-intact rings were precontracted with phenylephrine (0.001-30 μM) or high potassium (40 mM); endothelium-dependent/independent relaxant responses were obtained using acetylcholine (0.001-30 μM) and sodium nitroprusside (0.0001-3 μM), respectively. While phenylephrine sensitivity was significantly increased in OVX rats, relaxations were significantly less in aged OVX rats compared with young rats. In spite of the presence of estrogen antagonist, immediate SM treatment restored the endothelial function and vascular tone better than estrogen replacement. Additionally, as a complementary and alternative medicine, it does not cause estrogenic side effects when taken acutely. PMID:24123505

  10. Radionuclide angiography and blood pool imaging to assess skin ulcer healing prognosis in patients with peripheral vascular disease

    SciTech Connect

    Alazraki, N.; Lawrence, P.F.; Syverud, J.B.

    1984-01-01

    Several non-invasive diagnostic techniques including segmental limb blood pressures, skin fluoresence, and photo plethysmography, have been evaluated as predictors of skin ulcer healing in patients with peripheral vascular disease, but none are widely used. Using 20mCi of Tc-99m phosphate compounds, four phase bone scans were obtained, including (1) radionuclide angiogram (2) blood pool image (3) 2 hour and 4-6 hour static images and (4) 24 hour static delayed images. The first two phases were used to assess vacularity to the region of distal extremity ulceration; the last two phases evaluated presence or absence of osteomyelitis. Studies were performed in 30 patients with non-healing ulcers of the lower extremities. Perfusion to the regions of ulceration on images was graded as normal, increased, or reduced with respect to the opposite (presumed normal) limb or some other normal reference area. Hypervascular response was interpreted as good prognosis for healing unless osteomyelitis was present. Clinicians followed patients for 14 days to assess limb healing with optimum care. If there was no improvement, angiography and/or surgery (reconstructive surgery, sympathectomy, or amputation) was done. Results showed: sensitivity for predicting ulcer healing was 94%, specificity 89%. Patients who failed to heal their ulcers showed reduced perfusion, no hypervascular response, or osteomyelitis. Microcirculatory adequacy for ulcer healing appear predictable by this technique.

  11. Electrospray MS/MS reveals extensive and nonspecific oxidation of cholesterol esters in human peripheral vascular lesions[S

    PubMed Central

    Hutchins, Patrick M.; Moore, Ernest E.; Murphy, Robert C.

    2011-01-01

    Although LDL is rendered proatherogenic by various experimental treatments (e.g., acetylation), the exact structural changes that drive LDL transformation in vivo remain enigmatic. Among the many hypothesized targets of oxidative modification are cholesterol esters (CE). This family of neutral lipids, which carries a highly unsaturated pool of fatty acyl groups, is the main component of both LDL particles and atherosclerotic plaques. Tandem mass spectrometry (MS/MS) was employed to reveal abundant and diverse oxidized CEs (oxCE), including novel oxidation products, within human peripheral vascular lesions. These oxCE species composed up to 40% of the total CE pool, with cholesteryl linoleate being oxidized to the greatest extent. Imaging mass spectrometry studies showed that oxCE was entirely confined within the plaque, along with unmodified CE and triacylglyceride (TAG). Interestingly, we found no evidence for TAG oxidation, although polyunsaturated species were abundant. Enzymatic oxidation of cholesteryl linoleate by 15-lipoxygenase (15-LO), an enzyme often invoked in CE oxidation, initially results in a regio- and stereospecific product. Analysis of intact cholesteryl hydroxyoctadecadienoate isomers in human atheromata revealed no regio- or stereospecificity, indicating 15-LO was either not a major source of oxCE or nonenzymatic processes had eroded any product specificity. PMID:21885431

  12. Reporting standards of the Society for Vascular Surgery for endovascular treatment of chronic lower extremity peripheral artery disease.

    PubMed

    Stoner, Michael C; Calligaro, Keith D; Chaer, Rabih A; Dietzek, Alan M; Farber, Alik; Guzman, Raul J; Hamdan, Allen D; Landry, Greg J; Yamaguchi, Dean J

    2016-07-01

    Peripheral arterial disease (PAD) represents a spectrum from asymptomatic stenosis to limb-threatening ischemia. The last decade has seen a tremendous increase in the variety of endovascular devices and techniques to treat occlusive disease. Like many evolving technologies, the literature surrounding therapy for endovascular arterial disease consists of mixed-quality manuscripts without clear standardization. Accordingly, critical evaluation of the reported results may be problematic. As such, providers and their patients make treatment decisions without the full benefit of a comparative effectiveness framework. The purpose of this document is to provide a summary for the reporting of endovascular revascularization techniques in the setting of chronic disease. Much of the work in this document is based on prior publications and standards proposed by the Society for Vascular Surgery. We have also made recommendations based on current literature and have attempted to acknowledge shortcomings and areas for future research. The various sections contain summaries of required reporting standards and should serve as a guide for the design of clinical trials and as reference for journal editors and reviewers when considering scientific work pertaining to endovascular therapy for chronic lower extremity arterial disease. An Appendix is provided with commonly used abbreviations in this document. PMID:27345516

  13. Nifedipine in semi-solid formulations for topical use in peripheral vascular disease: preparation, characterization, and permeation assay.

    PubMed

    Santis, Ana Karla; de Freitas, Zaida Maria Faria; Ricci-Junior, Eduardo; de Brito-Gitirana, Lycia; Fonseca, Laís Bastos; Santos, Elisabete Pereira

    2013-07-01

    Nifedipine (NFD) has been used for the treatment of cutaneous lesions caused by peripheral vascular disease and diabetic ulcers. NFD was formulated at 8% in three semi-solid formulations: Polaxamer 407 Lecithin Organogel (PLO), PLO plus Transcutol(®), and an oil-in-water (o/w) emulsion. In vitro release and permeation tests were carried out using a synthetic (cellulose acetate) or natural membrane (pig ear skin), respectively, mounted in a Franz-type diffusion cell at 37°C in a constant water bath. As a receptor solution, isotonic phosphate buffer at pH 7.4 was used. All samples were analyzed by high-performance liquid chromatography by employing a previously validated method. The drug flow values were 6.126 ± 0.288, 4.030 ± 0.081, and 6.660 ± 0.254 μg/cm(2)/h for PLO, PLO plus Transcutol(®), and o/w emulsion, respectively. The three formulations did not show significant differences in drug flow, considering p > 0.05. Furthermore, their penetration profiles in both the epidermis and dermis were statistically different. Thus, the incorporation of NFD in PLO, PLO plus Transcutol(®), and o/w emulsion changed the drug thermodynamic activity, as expected. In addition, Transcutol(®) increased the solubility of NFD in the formulation and promoted its penetration in both the epidermis and dermis. PMID:22901029

  14. Physiologically Modeled Pulse Dynamics to Improve Function in In Vitro-Endothelialized Small-Diameter Vascular Grafts.

    PubMed

    Uzarski, Joseph S; Cores, Jhon; McFetridge, Peter S

    2015-11-01

    The lack of a functional endothelium on small-diameter vascular grafts leads to intimal hyperplasia and thrombotic occlusion. Shear stress conditioning through controlled hydrodynamics within in vitro perfusion bioreactors has shown promise as a mechanism to drive endothelial cell (EC) phenotype from an activated, pro-inflammatory wound state toward a quiescent functional state that inhibits responses that lead to occlusive failure. As part of an overall design strategy to engineer functional vascular grafts, we present a novel two-phase shear conditioning approach to improve graft endothelialization. Axial rotation was first used to seed uniform EC monolayers onto the lumenal surface of decellularized scaffolds derived from the human umbilical vein. Using computer-controlled perfusion circuits, a flow-ramping paradigm was applied to adapt endothelia to arterial levels of fluid shear stress and pressure without graft denudation. The effects of constant pulse frequencies (CF) on EC quiescence were then compared with pulse frequencies modeled from temporal fluctuations in blood flow observed in vivo, termed physiologically modeled pulse dynamics (PMPD). Constructs exposed to PMPD for 72 h expressed a more functional transcriptional profile, lower metabolic activity (39.8% ± 8.4% vs. 62.5% ± 11.5% reduction, p = 0.012), and higher nitric oxide production (80.42 ± 23.93 vs. 48.75 ± 6.93 nmol/10(5) cells, p = 0.028) than those exposed to CF. By manipulating in vitro flow conditions to mimic natural physiology, endothelialized vascular grafts can be stimulated to express a nonactivated phenotype that would better inhibit peripheral cell adhesion and smooth muscle cell hyperplasia, conditions that typically lead to occlusive failure. Development of robust, functional endothelia on vascular grafts by modulation of environmental conditions within perfusion bioreactors may ultimately improve clinical outcomes in vascular bypass grafting. PMID:25996580

  15. Immunomodulation of vascular endothelium. 1. Ultrastructural changes following ultraviolet B irradiation of peripheral veins

    SciTech Connect

    Marin, M.L.; Gordon, R.E.; Hardy, M.A.; Reemtsma, K.; Benvenisty, A.I. )

    1990-02-01

    Immunologic function of endothelial cells is especially important in consideration of vein allografting for arterial reconstruction and in organ allotransplantation. Ultraviolet B radiation (UVB) has previously been shown to modulate graft immunogenicity, and to alter cell surface receptor function. In this study, superficial epigastric veins were UVB irradiated with 10, 24, 40, 80, and 150 mJ/cm2 while control veins were not irradiated; all specimens were examined for endothelial ultrastructural changes. Veins were perfuse-fixed at 1, 3, 7, 14, and 28 days after irradiation, and were evaluated by transmission electron microscopy and scanning electron microscopy. Control veins had a normal appearing endothelial lining, composed of elongated, attenuated endothelial cells. Veins irradiated with more than 24 mJ/cm2 displayed injured endothelial cells characterized by altered microvilli, defects in the cell surface, and a change in cell shape. The degree of cell damage correlated closely with increasing UVB dose. At doses of 80 mJ/cm2 or greater there was moderate to severe endothelial cell separation from the underlying basement membrane and an increase in cellular lysosomes. The effects of UVB were maximal at 3 days with virtual recovery in resurfacing of all specimens with endothelium 28 days after irradiation. These data suggest that UVB has a dose-dependent effect on venous endothelium that is morphologically reversible with time. Cell membrane changes seen following exposure to UVB may contribute to altered cell surface receptor function.

  16. Relationships between retinal arteriole anatomy and aortic geometry and function and peripheral resistance in hypertensives.

    PubMed

    Rosenbaum, David; Kachenoura, Nadjia; Koch, Edouard; Paques, Michel; Cluzel, Philippe; Redheuil, Alban; Girerd, Xavier

    2016-07-01

    Microvascular remodeling and large artery stiffness are key determinants of cardiovascular hemodynamics and can now be studied with new non-invasive methods. Our objective was to study the relationships between retinal arteriole anatomy and aortic geometry and function and peripheral resistance (total peripheral resistance (TPR)) in hypertensives. In 80 subjects (age 52±13 years; 53% males; including 23 normotensives and 57 hypertensives, among which 29 were uncontrolled hypertensives), we used: (1) the new non-invasive RTX1 adaptive optics (AO) camera (Imagine Eyes, Orsay, France) to measure the wall-to-lumen ratio (WLR) on retinal microvasculature; (2) cardiovascular magnetic resonance (CMR) imaging to assess aortic stiffness, geometry and cardiac output; and (3) the validated SphymoCor Xcel device to measure central blood pressure (BP) and carotido-femoral pulse wave velocity (Cf-PWV). TPR was calculated as the central mean BP/cardiac output ratio. WLR and TPR were significantly higher and aortic distensibility was significantly lower in hypertensives. Aortic dilation and arch elongation were found in uncontrolled hypertensives. In the univariate analysis, WLR was positively correlated with central BP (P<0.001), TPR (P<0.001) and Cf-PWV (P<0.05), and it was negatively correlated with aortic distensibility (P=0.003); however, it was not correlated with age or cardiovascular risk factors. The multivariate analysis indicated that WLR was associated with TPR (P=0.002) independent of age, BMI, gender, antihypertensive treatments, aortic diameter and central SBP. As expected, age was the major correlate of ascending aorta distensibility and Cf-PWV. New non-invasive vascular imaging methods are complementary for the detection of the deleterious effects of aging or high BP on large and small arteries. AO examination could represent a useful tool for the study and follow-up of microvasculature anatomical changes. PMID:27009576

  17. ELIMINATION OF VITAMIN D RECEPTOR IN VASCULAR ENDOTHELIAL CELLS ALTERS VASCULAR FUNCTION

    PubMed Central

    Ni, Wei; Watts, Stephanie W.; Ng, Michael; Chen, Songcang; Glenn, Denis J.; Gardner, David G.

    2014-01-01

    Vitamin D deficiency has been associated with cardiovascular dysfunction. We evaluated the role of the vitamin D receptor (VDR) in vascular endothelial function, a marker of cardiovascular health, at baseline and in the presence of angiotensin II, using an endothelial-specific knockout of the murine VDR gene. In the absence of endothelial VDR, acetylcholine-induced aortic relaxation was significantly impaired (maximal relaxation, endothelial-specific VDR knockout =58% vs. control=73%, p<0.05). This was accompanied by a reduction in eNOS expression and phospho-vasodilator-stimulated phosphoprotein levels in aortae from the endothelial-specific VDR knockout vs. control mice. While blood pressure levels at baseline were comparable at 12 and 24 weeks of age, the endothelial VDR knockout mice demonstrated increased sensitivity to the hypertensive effects of angiotensin II compared to control mice (after 1-week infusion: knockout = 155±15 mmHg vs. control = 133±7 mmHg, p<0.01; after 2-week infusion: knockout = 164±9 mmHg vs. control = 152±13 mmHg, p<0.05). By the end of two weeks, angiotensin II infusion-induced, hypertrophy-sensitive myocardial gene expression was higher in endothelial-specific VDR knockout mice (fold change compared to saline-infused control mice, ANP: knockout mice = 3.12 vs. control= 1.7, p<0.05; BNP: knockout mice= 4.72 vs. control= 2.68, p<0.05). These results suggest that endothelial VDR plays an important role in endothelial cell function and blood pressure control and imply a potential role for VDR agonists in the management of cardiovascular disease associated with endothelial dysfunction. PMID:25201890

  18. Vascular endothelial function of patients with stable coronary artery disease

    PubMed Central

    Wang, Zhe; Yang, Xinchun; Cai, Jun; Shi, Hui; Zhong, Guangzhen; Chi, Hongjie

    2015-01-01

    Objectives: To evaluate vascular endothelial function and contributing factors in coronary heart disease (CHD) patients. Methods: One hundred twenty six CHD outpatients were randomly recruited. Reactive hyperemia index (RHI) <1.67 indicates endothelial dysfunction. Correlation between RHI and different biochemical parameters was evaluated. Results: RHI in patients receiving statins treatment was significantly higher than patients without statins treatment (P<0.05). RHI in patients with more than 3 risk factors for CHD was also markedly lower than that in patients with ≤2 risk factors (P<0.05). Patients with lesions at several branches of coronary artery had a markedly lower RHI when compared with those with coronary lesions at a single branch (P<0.05). For patients without statins treatment, RHI increased significantly after statins treatment for 1 month (P=0.01). In patients with endothelial dysfunction, FBG, HbA1C, hs-CRP and Hcy were significantly higher than those in patients with normal endothelial function (P<0.05 for all). Smokers with CHD had a remarkably lower RHI when compared with non-smokers (P<0.05). Conclusions: Smoking, FBG, HbA1C, Hcy and hs-CRP are significantly associated with endothelial dysfunction. Endothelial dysfunction is also related to the numbers of risk factors for CHD, degree of coronary lesions and statins. Statins treatment may significantly improve the endothelial function of CHD patients. PMID:26150839

  19. Urinary Albumin Excretion and Vascular Function in Rheumatoid Arthritis

    PubMed Central

    2016-01-01

    Rheumatoid arthritis (RA) is associated with significant cardiovascular (CV) morbidity and mortality. Increased urinary albumin excretion is a marker of CV risk. There are only few data on urinary albumin excretion in RA patients. Aim of the present study was to investigate urinary albumin excretion in RA patients and analyze, whether there is an association between urinary albumin excretion and vascular function as measured by the augmentation index (AIx). In a total of 341 participants (215 with RA, 126 without RA) urinary albumin-creatinine ratio (ACR) was determined and the AIx was measured. The Kolmogorov-Smirnov-test was used to cluster patient groups whose distributions of ACR can be considered to be equal. A crude analysis showed a median ACR of 6.6 mg/g in the RA group and 5.7 mg/g in patients without RA (P > 0.05). In order to account for diabetes (DM) we formed 4 distinct patient groups. Group 1: RA-/DM- (n = 74); group 2: RA+/DM- (n = 195); group 3: RA-/DM+ (n = 52); group 4: RA+/DM+ (n = 20). Clustering of these groups revealed two distinct patient groups: those without RA and DM, and those with either RA or DM or both. The latter group showed statistically significant higher ACR (median 8.1 mg/g) as the former (median 4.5 mg/g). We found no significant correlation between AIx and ACR. Urinary albumin excretion in patients with RA or DM or both is higher than in subjects without RA and DM. This can be seen as a sign of vascular alteration and increased CV risk in these patients. PMID:26955238

  20. Urinary Albumin Excretion and Vascular Function in Rheumatoid Arthritis.

    PubMed

    Pieringer, Herwig; Brummaier, Tobias; Piringer, Bettina; Auer-Hackenberg, Lorenz; Hartl, Andreas; Puchner, Rudolf; Pohanka, Erich; Schmid, Michael

    2016-03-01

    Rheumatoid arthritis (RA) is associated with significant cardiovascular (CV) morbidity and mortality. Increased urinary albumin excretion is a marker of CV risk. There are only few data on urinary albumin excretion in RA patients. Aim of the present study was to investigate urinary albumin excretion in RA patients and analyze, whether there is an association between urinary albumin excretion and vascular function as measured by the augmentation index (AIx). In a total of 341 participants (215 with RA, 126 without RA) urinary albumin-creatinine ratio (ACR) was determined and the AIx was measured. The Kolmogorov-Smirnov-test was used to cluster patient groups whose distributions of ACR can be considered to be equal. A crude analysis showed a median ACR of 6.6 mg/g in the RA group and 5.7 mg/g in patients without RA (P > 0.05). In order to account for diabetes (DM) we formed 4 distinct patient groups. Group 1: RA-/DM- (n = 74); group 2: RA+/DM- (n = 195); group 3: RA-/DM+ (n = 52); group 4: RA+/DM+ (n = 20). Clustering of these groups revealed two distinct patient groups: those without RA and DM, and those with either RA or DM or both. The latter group showed statistically significant higher ACR (median 8.1 mg/g) as the former (median 4.5 mg/g). We found no significant correlation between AIx and ACR. Urinary albumin excretion in patients with RA or DM or both is higher than in subjects without RA and DM. This can be seen as a sign of vascular alteration and increased CV risk in these patients. PMID:26955238

  1. VEGF induces sensory and motor peripheral plasticity, alters bladder function, and promotes visceral sensitivity

    PubMed Central

    2012-01-01

    Background This work tests the hypothesis that bladder instillation with vascular endothelial growth factor (VEGF) modulates sensory and motor nerve plasticity, and, consequently, bladder function and visceral sensitivity. In addition to C57BL/6J, ChAT-cre mice were used for visualization of bladder cholinergic nerves. The direct effect of VEGF on the density of sensory nerves expressing the transient receptor potential vanilloid subfamily 1 (TRPV1) and cholinergic nerves (ChAT) was studied one week after one or two intravesical instillations of the growth factor. To study the effects of VEGF on bladder function, mice were intravesically instilled with VEGF and urodynamic evaluation was assessed. VEGF-induced alteration in bladder dorsal root ganglion (DRG) neurons was performed on retrogradly labeled urinary bladder afferents by patch-clamp recording of voltage gated Na+ currents. Determination of VEGF-induced changes in sensitivity to abdominal mechanostimulation was performed by application of von Frey filaments. Results In addition to an overwhelming increase in TRPV1 immunoreactivity, VEGF instillation resulted in an increase in ChAT-directed expression of a fluorescent protein in several layers of the urinary bladder. Intravesical VEGF caused a profound change in the function of the urinary bladder: acute VEGF (1 week post VEGF treatment) reduced micturition pressure and longer treatment (2 weeks post-VEGF instillation) caused a substantial reduction in inter-micturition interval. In addition, intravesical VEGF resulted in an up-regulation of voltage gated Na+ channels (VGSC) in bladder DRG neurons and enhanced abdominal sensitivity to mechanical stimulation. Conclusions For the first time, evidence is presented indicating that VEGF instillation into the mouse bladder promotes a significant increase in peripheral nerve density together with alterations in bladder function and visceral sensitivity. The VEGF pathway is being proposed as a key modulator of

  2. ALDOSTERONE DYSREGULATION WITH AGING PREDICTS RENAL-VASCULAR FUNCTION AND CARDIO-VASCULAR RISK

    PubMed Central

    Brown, Jenifer M.; Underwood, Patricia C.; Ferri, Claudio; Hopkins, Paul N.; Williams, Gordon H.; Adler, Gail K.; Vaidya, Anand

    2014-01-01

    Aging and abnormal aldosterone regulation are both associated with vascular disease. We hypothesized that aldosterone dysregulation influences the age-related risk of renal- and cardio-vascular disease. We conducted an analysis of 562 subjects who underwent detailed investigations under conditions of liberal and restricted dietary sodium intake (1,124 visits) in a Clinical Research Center. Aldosterone regulation was characterized by the ratio of maximal suppression-to-stimulation (supine serum aldosterone on a liberal sodium diet divided by the same measure on a restricted sodium diet). We previously demonstrated that higher levels of this Sodium-modulated Aldosterone Suppression-Stimulation Index (SASSI) indicate greater aldosterone dysregulation. Renal plasma flow (RPF) was determined via p-aminohippurate clearance to assess basal renal hemodynamics, and the renal-vascular responses to dietary sodium manipulation and angiotensin II (AngII) infusion. Cardiovascular risk was calculated using the Framingham Risk Score. In univariate linear regression, older age (β= -4.60, p<0.0001) and higher SASSI (β= -58.63, p=0.001) predicted lower RPF and a blunted RPF response to sodium loading and AngII infusion. We observed a continuous, independent, multivariate-adjusted interaction between age and SASSI, where the inverse relationship between SASSI and RPF was most apparent with older age (p<0.05). Higher SASSI and lower RPF independently predicted higher Framingham Risk Score (p<0.0001) and together displayed an additive effect. Aldosterone regulation and age may interact to mediate renal-vascular disease. Our findings suggest that the combination of aldosterone dysregulation and renal-vascular dysfunction could additively increase the risk of future cardiovascular outcomes; therefore, aldosterone dysregulation may represent a modifiable mechanism of age-related vascular disease. PMID:24664291

  3. Review of gestational diabetes mellitus effects on vascular structure and function.

    PubMed

    Jensen, Louise A; Chik, Constance L; Ryan, Edmond A

    2016-05-01

    Vascular dysfunction has been described in women with a history of gestational diabetes mellitus. Furthermore, previous gestational diabetes mellitus increases the risk of developing Type 2 diabetes mellitus, a risk factor for cardiovascular disease. Factors contributing to vascular changes remain uncertain. The aim of this review was to summarize vascular structure and function changes found to occur in women with previous gestational diabetes mellitus and to identify factors that contribute to vascular dysfunction. A systematic search of electronic databases yielded 15 publications from 1998 to March 2014 that met the inclusion criteria. Our review confirmed that previous gestational diabetes mellitus contributes to vascular dysfunction, and the most consistent risk factor associated with previous gestational diabetes mellitus and vascular dysfunction was elevated body mass index. Heterogeneity existed across studies in determining the relationship of glycaemic levels and insulin resistance to vascular dysfunction. PMID:26940821

  4. Efficacy and Safety of a Novel Vascular Closure Device (Glubran 2 Seal) After Diagnostic and Interventional Angiography in Patients with Peripheral Arterial Occlusive Disease

    SciTech Connect

    Del Corso, Andrea; Bargellini, Irene Cicorelli, Antonio; Perrone, Orsola; Leo, Michele; Lunardi, Alessandro; Alberti, Aldo; Tomei, Francesca; Cioni, Roberto; Ferrari, Mauro; Bartolozzi, Carlo

    2013-04-15

    To prospectively evaluate safety and efficacy of a novel vascular closure device (Glubran 2 Seal) after peripheral angiography in patients with peripheral arterial occlusive disease (PAOD). From December 2010 to June 2011, all consecutive patients with PAOD undergoing peripheral angiography were prospectively enrolled onto the study after percutaneous antegrade or retrograde puncture of the common femoral artery. After angiography, the Glubran 2 Seal device was used to achieve hemostasis. The following data were registered: technical success and manual compression duration, patients' discomfort (scale 0-5), operators' technical difficulty (scale 0-5), and vascular complications. The site of hemostasis was evaluated by clinical inspection and color-coded Duplex ultrasound performed 1 day and 1 month after the procedure. One hundred seventy-eight patients were enrolled (112 male, mean age 70.8 years) with a total of 206 puncture sites, including 104 (50.5 %) antegrade accesses. The device was successful in 198(96.1 %) of 206 procedures, with 8 cases of manual compression lasting longer than 5 min (maximum 20 min). No major vascular complications were observed, resulting in 100 % procedural success. Minor complications occurred in seven procedures (3.4 %), including two cases of pseudoaneurysms, successfully treated by ultrasound-guided glue injection. The mean {+-} standard deviation score for patients' discomfort was 0.9 {+-} 0.7, whereas the mean score for operators' difficulty was 1.2 {+-} 0.9. In patients with PAOD, the Glubran 2 Seal represents a simple, painless, and efficient vascular closure device, able to achieve hemostasis both in antegrade and retrograde accesses.

  5. Grape polyphenols do not affect vascular function in healthy men.

    PubMed

    van Mierlo, Linda A J; Zock, Peter L; van der Knaap, Henk C M; Draijer, Richard

    2010-10-01

    Data suggest that polyphenol-rich products may improve endothelial function and other cardiovascular health risk factors. Grape and wine contain high amounts of polyphenols, but effects of these polyphenols have hardly been investigated in isolation in randomized controlled studies. Our objective in this study was to test the chronic effect of polyphenol-rich solids derived from either a wine grape mix or grape seed on flow-mediated dilation (FMD). Blood pressure and other vascular function measures, platelet function, and blood lipids were secondary outcomes. Thirty-five healthy males were randomized in a double-blind, placebo-controlled crossover study consisting of three 2-wk intervention periods separated by 1-wk washout periods. The test products, containing 800 mg of polyphenols, were consumed as capsules. At the end of each intervention period, effects were measured after consumption of a low-fat breakfast (~751 kJ, 25% fat) and a high-fat lunch (~3136 kJ, 78% fat). After the low-fat breakfast, the treatments did not significantly affect FMD. The absolute difference after the wine grape solid treatment was -0.4% (95% CI = -1.8 to 0.9; P = 0.77) and after grape seed solids, 0.2% (95% CI = -1.2 to 1.5; P = 0.94) compared with after the placebo treatment. FMD effects after the high-fat lunch and effects on secondary outcomes also showed no consistent differences between both of the grape solids and placebo treatment. In conclusion, consumption of grape polyphenols has no major impact on FMD in healthy men. Future studies should address whether grape polyphenols can improve FMD and other cardiovascular health risk factors in populations with increased cardiovascular risk. PMID:20702747

  6. Regulation of Vascular and Renal Function by Metabolite Receptors.

    PubMed

    Peti-Peterdi, János; Kishore, Bellamkonda K; Pluznick, Jennifer L

    2016-01-01

    To maintain metabolic homeostasis, the body must be able to monitor the concentration of a large number of substances, including metabolites, in real time and to use that information to regulate the activities of different metabolic pathways. Such regulation is achieved by the presence of sensors, termed metabolite receptors, in various tissues and cells of the body, which in turn convey the information to appropriate regulatory or positive or negative feedback systems. In this review, we cover the unique roles of metabolite receptors in renal and vascular function. These receptors play a wide variety of important roles in maintaining various aspects of homeostasis-from salt and water balance to metabolism-by sensing metabolites from a wide variety of sources. We discuss the role of metabolite sensors in sensing metabolites generated locally, metabolites generated at distant tissues or organs, or even metabolites generated by resident microbes. Metabolite receptors are also involved in various pathophysiological conditions and are being recognized as potential targets for new drugs. By highlighting three receptor families-(a) citric acid cycle intermediate receptors, (b) purinergic receptors, and PMID:26667077

  7. Functional CB1 cannabinoid receptors in human vascular endothelial cells.

    PubMed Central

    Liu, J; Gao, B; Mirshahi, F; Sanyal, A J; Khanolkar, A D; Makriyannis, A; Kunos, G

    2000-01-01

    Cannabinoid CB1 receptor mRNA was detected using reverse transcription-polymerase chain reaction (RT-PCR) in endothelial cells from human aorta and hepatic artery and in the ECV304 cell line derived from human umbilical vein endothelial cells. CB1 receptor-binding sites were detected by the high-affinity antagonist radioligand [(125)I]AM-251. In ECV304 cells, both the highly potent synthetic cannabinoid agonist HU-210 and the endogenous ligand anandamide induce activation of mitogen-activated protein (MAP) kinase, and the effect of HU-210 was completely blocked, whereas the effect of anandamide was partially inhibited by SR141716A, a selective CB1 receptor antagonist. Transfection of ECV304 cells with CB1 receptor antisense, but not sense, oligonucleotides caused the same pattern of inhibition as SR141716A. This provides more definitive evidence for the involvement of CB1 receptors in MAP kinase activation and suggests that anandamide may also activate MAP kinase via an additional, CB1 receptor-independent, SR141716A-resistant mechanism. The MAP kinase activation by anandamide in ECV304 cells requires genistein-sensitive tyrosine kinases and protein kinase C (PKC), and anandamide also activates p38 kinase and c-Jun kinase. These findings indicate that CB1 receptors located in human vascular endothelium are functionally coupled to the MAP kinase cascade. Activation of protein kinase cascades by anandamide may be involved in the modulation of endothelial cell growth and proliferation. PMID:10698714

  8. Functional properties of ion channels and transporters in tumour vascularization

    PubMed Central

    Fiorio Pla, Alessandra; Munaron, Luca

    2014-01-01

    Vascularization is crucial for solid tumour growth and invasion, providing metabolic support and sustaining metastatic dissemination. It is now accepted that ion channels and transporters play a significant role in driving the cancer growth at all stages. They may represent novel therapeutic, diagnostic and prognostic targets for anti-cancer therapies. On the other hand, although the expression and role of ion channels and transporters in the vascular endothelium is well recognized and subject of recent reviews, only recently has their involvement in tumour vascularization been recognized. Here, we review the current literature on ion channels and transporters directly involved in the angiogenic process. Particular interest will be focused on tumour angiogenesis in vivo as well as in the different steps that drive this process in vitro, such as endothelial cell proliferation, migration, adhesion and tubulogenesis. Moreover, we compare the ‘transportome’ system of tumour vascular network with the physiological one. PMID:24493751

  9. Childhood Obesity Associates Haemodynamic and Vascular Changes That Result in Increased Central Aortic Pressure with Augmented Incident and Reflected Wave Components, without Changes in Peripheral Amplification.

    PubMed

    Castro, Juan M; García-Espinosa, Victoria; Curcio, Santiago; Arana, Maite; Chiesa, Pedro; Giachetto, Gustavo; Zócalo, Yanina; Bia, Daniel

    2016-01-01

    The aims were to determine if childhood obesity is associated with increased central aortic blood pressure (BP) and to characterize haemodynamic and vascular changes associated with BP changes in obese children and adolescents by means of analyzing changes in cardiac output (stroke volume, SV), arterial stiffness (aortic pulse wave velocity, PWV), peripheral vascular resistances (PVR), and net and relative contributions of reflected waves to the aortic pulse wave amplitude. We included 117 subjects (mean/range age: 10 (5-15) years, 49 females), who were obese (OB) or had normal weight (NW). Peripheral and central aortic BP, PWV, and pulse wave-derived parameters (augmentation index, amplitude of forward and backward components) were measured with tonometry (SphygmoCor) and oscillometry (Mobil-O-Graph). With independence of the presence of dyslipidemia, hypertension, or sedentarism, the aortic systolic and pulse BP were higher in OB than in NW subjects. The increase in central BP could not be explained by the elevation in the relative contribution of reflections to the aortic pressure wave and higher PVR or by an augmented peripheral reflection coefficient. Instead, the rise in central BP could be explained by an increase in the amplitude of both incident and reflect wave components associated to augmented SV and/or PWV. PMID:26881081

  10. Childhood Obesity Associates Haemodynamic and Vascular Changes That Result in Increased Central Aortic Pressure with Augmented Incident and Reflected Wave Components, without Changes in Peripheral Amplification

    PubMed Central

    Castro, Juan M.; García-Espinosa, Victoria; Curcio, Santiago; Arana, Maite; Chiesa, Pedro; Giachetto, Gustavo; Zócalo, Yanina; Bia, Daniel

    2016-01-01

    The aims were to determine if childhood obesity is associated with increased central aortic blood pressure (BP) and to characterize haemodynamic and vascular changes associated with BP changes in obese children and adolescents by means of analyzing changes in cardiac output (stroke volume, SV), arterial stiffness (aortic pulse wave velocity, PWV), peripheral vascular resistances (PVR), and net and relative contributions of reflected waves to the aortic pulse wave amplitude. We included 117 subjects (mean/range age: 10 (5–15) years, 49 females), who were obese (OB) or had normal weight (NW). Peripheral and central aortic BP, PWV, and pulse wave-derived parameters (augmentation index, amplitude of forward and backward components) were measured with tonometry (SphygmoCor) and oscillometry (Mobil-O-Graph). With independence of the presence of dyslipidemia, hypertension, or sedentarism, the aortic systolic and pulse BP were higher in OB than in NW subjects. The increase in central BP could not be explained by the elevation in the relative contribution of reflections to the aortic pressure wave and higher PVR or by an augmented peripheral reflection coefficient. Instead, the rise in central BP could be explained by an increase in the amplitude of both incident and reflect wave components associated to augmented SV and/or PWV. PMID:26881081

  11. Schwann cell mitochondrial metabolism supports long-term axonal survival and peripheral nerve function

    PubMed Central

    Viader, Andreu; Golden, Judith P.; Baloh, Robert H.; Schmidt, Robert E.; Hunter, Daniel A.; Milbrandt, Jeffrey

    2011-01-01

    Mitochondrial dysfunction is a common cause of peripheral neuropathies. While the role of neuron and axonal mitochondria in peripheral nerve disease is well appreciated, whether Schwann cell (SC) mitochondrial deficits contribute to peripheral neuropathies is unclear. Here we examine how SC mitochondrial dysfunction affects axonal survival and contributes to the decline of peripheral nerve function by generating mice with SC-specific mitochondrial deficits. These mice (Tfam-SCKOs) were produced through the tissue-specific deletion of the mitochondrial transcription factor A gene (Tfam), which is essential for mitochondrial DNA (mtDNA) transcription and maintenance. Tfam-SCKOs were viable but, as they aged, they developed a progressive peripheral neuropathy characterized by nerve conduction abnormalities as well as extensive muscle denervation. Morphological examination of Tfam-SCKO nerves revealed early preferential loss of small unmyelinated fibers followed by prominent demyelination and degeneration of larger-caliber axons. Tfam-SCKOs displayed sensory and motor deficits consistent with this pathology. Remarkably, the severe mtDNA depletion and respiratory chain abnormalities in Tfam-SCKO mice did not affect SC proliferation or survival. Mitochondrial function in SCs is therefore essential for maintenance of axonal survival and normal peripheral nerve function, suggesting that SC mitochondrial dysfunction contributes to human peripheral neuropathies. PMID:21752989

  12. Conventional and Functional MR Imaging of Peripheral Nerve Sheath Tumors: Initial Experience

    PubMed Central

    Demehri, S.; Belzberg, A.; Blakeley, J.; Fayad, L.M.

    2015-01-01

    BACKGROUND AND PURPOSE Differentiating benign from malignant peripheral nerve sheath tumors can be very challenging using conventional MR imaging. Our aim was to test the hypothesis that conventional and functional MR imaging can accurately diagnose malignancy in patients with indeterminate peripheral nerve sheath tumors. MATERIALS AND METHODS This institutional review board–approved, Health Insurance Portability and Accountability Act–compliant study retrospectively reviewed 61 consecutive patients with 80 indeterminate peripheral nerve sheath tumors. Of these, 31 histologically proved peripheral nerve sheath tumors imaged with conventional (unenhanced T1, fluid-sensitive, contrast-enhanced T1-weighted sequences) and functional MR imaging (DWI/apparent diffusion coefficient mapping, dynamic contrast-enhanced MR imaging) were included. Two observers independently assessed anatomic (size, morphology, signal) and functional (ADC values, early arterial enhancement by dynamic contrast-enhanced MR) features to determine interobserver agreement. The accuracy of MR imaging for differentiating malignant from benign was also determined by receiver operating characteristic analysis. RESULTS Of 31 peripheral nerve sheath tumors, there were 9 malignant (9%) and 22 benign ones (81%). With anatomic sequences, average tumor diameter (6.3 ± 1.8 versus 3.9 ± 2.3 mm, P = .009), ill-defined/infiltrative margins (77% versus 32%; P = .04), and the presence of peritumoral edema (66% versus 23%, P = .01) were different for malignant peripheral nerve sheath tumors and benign peripheral nerve sheath tumors. With functional sequences, minimum ADC (0.47 ± 0.32 × 10−3 mm2/s versus 1.08 ± 0.26 × 10−3 mm2/s; P [H11021] .0001) and the presence of early arterial enhancement (50% versus 11%; P = .03) were different for malignant peripheral nerve sheath tumors and benign peripheral nerve sheath tumors. The minimum ADC (area under receiver operating characteristic curve was 0.89; 95

  13. Vascular Endothelial Growth Factor Modulates Skeletal Myoblast Function

    PubMed Central

    Germani, Antonia; Di Carlo, Anna; Mangoni, Antonella; Straino, Stefania; Giacinti, Cristina; Turrini, Paolo; Biglioli, Paolo; Capogrossi, Maurizio C.

    2003-01-01

    Vascular endothelial growth factor (VEGF) expression is enhanced in ischemic skeletal muscle and is thought to play a key role in the angiogenic response to ischemia. However, it is still unknown whether, in addition to new blood vessel growth, VEGF modulates skeletal muscle cell function. In the present study immunohistochemical analysis showed that, in normoperfused mouse hindlimb, VEGF and its receptors Flk-1 and Flt-1 were expressed mostly in quiescent satellite cells. Unilateral hindlimb ischemia was induced by left femoral artery ligation. At day 3 and day 7 after the induction of ischemia, Flk-1 and Flt-1 were expressed in regenerating muscle fibers and VEGF expression by these fibers was markedly enhanced. Additional in vitro experiments showed that in growing medium both cultured satellite cells and myoblast cell line C2C12 expressed VEGF and its receptors. Under these conditions, Flk-1 receptor exhibited constitutive tyrosine phosphorylation that was increased by VEGF treatment. During myogenic differentiation Flk-1 and Flt-1 were down-regulated. In a modified Boyden Chamber assay, VEGF enhanced C2C12 myoblasts migration approximately fivefold. Moreover, VEGF administration to differentiating C2C12 myoblasts prevented apoptosis, while inhibition of VEGF signaling either with selective VEGF receptor inhibitors (SU1498 and CB676475) or a neutralizing Flk-1 antibody, enhanced cell death approximately 3.5-fold. Finally, adenovirus-mediated VEGF165 gene transfer inhibited ischemia-induced apoptosis in skeletal muscle. These results support a role for VEGF in myoblast migration and survival, and suggest a novel autocrine role of VEGF in skeletal muscle repair during ischemia. PMID:14507649

  14. Mimicking Form and Function of Native Small Diameter Vascular Conduits Using Mulberry and Non-mulberry Patterned Silk Films.

    PubMed

    Gupta, Prerak; Kumar, Manishekhar; Bhardwaj, Nandana; Kumar, Jadi Praveen; Krishnamurthy, C S; Nandi, Samit Kumar; Mandal, Biman B

    2016-06-29

    Autologous graft replacement as a strategy to treat diseased peripheral small diameter (≤6 mm) blood vessel is often challenged by prior vein harvesting. To address this issue, we fabricated native-tissue mimicking multilayered small diameter vascular graft (SDVG) using mulberry (Bombyx mori) and Indian endemic non-mulberry (Antheraea assama and Philosamia ricini) silk. Patterned silk films were fabricated on microgrooved PDMS mold, casted by soft lithography. The biodegradable patterned film templates with aligned cell sheets were rolled onto an inert mandrel to mimic vascular conduit. The hemocompatible and mechanically strong non-mulberry films with RGD motif supported ∼1.2 folds greater proliferation of vascular cells with aligned anchorage. Elicitation of minimal immune response on subcutaneous implantation of the films in mice was complemented by ∼45% lower TNF α secretion by in vitro macrophage culture post 7 days. Pattern-induced alignment favored the functional contractile phenotype of smooth muscle cells (SMCs), expressing the signature markers-calponin, α-smooth muscle actin (α-SMA), and smooth muscle myosin heavy chain (SM-MHC). Endothelial cells (ECs) exhibited a typical punctuated pattern of von Willebrand factor (vWF). Deposition of collagen and elastin by the SMCs substantiated the aptness of the graft with desired biomechanical attributes. Furthermore, the burst strength of the fabricated conduit was in the range of ∼915-1260 mmHg, a prerequisite to withstand physiological pressure. This novel fabrication approach may eliminate the need of maturation in a pulsatile bioreactor for obtaining functional cellular phenotype. This work is thereby an attestation to the immense prospects of exploring non-mulberry silk for bioengineering a multilayered vascular conduit similar to a native vessel in "form and function", befitting for in vivo transplantation. PMID:27269821

  15. Two Serious Complications of Peripherally Inserted Central Catheters Indicating the Need to Formalize Training for Placing Central Venous Vascular Access Devices.

    PubMed

    Gerling, Volker; Feenstra, Nico

    2016-02-15

    Peripherally inserted central catheters are being used in increasing numbers. Common (thrombosis, infection, phlebitis, malfunction, or disconnection) and rare complications (pericardial tamponade) have been well explored. We describe 2 serious complications that resolved without sequelae. Both complications occurred in the context of limited provider competence. We conclude that vascular access is more than "just" placing a catheter; it can have serious clinical impact and has evolved into a specialist skill. With increasing use of intravascular catheters, the need for a formalized training becomes urgent. PMID:26517231

  16. Impairment of endothelial progenitor cell function and vascularization capacity by aldosterone in mice and humans

    PubMed Central

    Thum, Thomas; Schmitter, Kerstin; Fleissner, Felix; Wiebking, Volker; Dietrich, Bernd; Widder, Julian D.; Jazbutyte, Virginija; Hahner, Stefanie; Ertl, Georg; Bauersachs, Johann

    2011-01-01

    Aims Hyperaldosteronism is associated with vascular injury and increased cardiovascular events. Bone marrow-derived endothelial progenitor cells (EPCs) play an important role in endothelial repair and vascular homeostasis. We hypothesized that hyperaldosteronism impairs EPC function and vascularization capacity in mice and humans. Methods and results We characterized the effects of aldosterone and mineralocorticoid receptor (MR) blockade on EPC number and function as well as vascularization capacity and endothelial function. Treatment of human EPC with aldosterone induced translocation of the MR and impaired multiple cellular functions of EPC, such as differentiation, migration, and proliferation in vitro. Impaired EPC function was rescued by pharmacological blockade or genetic ablation of the MR. Aldosterone protein kinase A (PKA) dependently increased reactive oxygen species formation in EPC. Aldosterone infusion in mice impaired EPC function, EPC homing to vascular structures and vascularization capacity in a MR-dependent but blood pressure-independent manner. Endothelial progenitor cells from patients with primary hyperaldosteronism compared with controls of similar age displayed reduced migratory potential. Impaired EPC function was associated with endothelial dysfunction. MR blockade in patients with hyperaldosteronism improved EPC function and arterial stiffness. Conclusion Endothelial progenitor cells express a MR that mediates functional impairment by PKA-dependent increase of reactive oxygen species. Normalization of EPC function may represent a novel mechanism contributing to the beneficial effects of MR blockade in cardiovascular disease prevention and treatment. PMID:20926363

  17. Microfluidic Capture of Endothelial Colony-Forming Cells from Human Adult Peripheral Blood: Phenotypic and Functional Validation In Vivo

    PubMed Central

    Lin, Ruei-Zeng; Hatch, Adam; Antontsev, Victor G.; Murthy, Shashi K.

    2015-01-01

    Introduction: Endothelial colony-forming cells (ECFCs) are endothelial progenitors that circulate in peripheral blood and are currently the subject of intensive investigation due to their therapeutic potential. However, in adults, ECFCs comprise a very small subset among circulating cells, which makes their isolation a challenge. Materials and Methods: Currently, the standard method for ECFC isolation relies on the separation of mononuclear cells and erythrocyte lysis, steps that are time consuming and known to increase cell loss. Alternatively, we previously developed a novel disposable microfluidic platform containing antibody-functionalized degradable hydrogel coatings that is ideally suited for capturing low-abundance circulating cells from unprocessed blood. In this study, we reasoned that this microfluidic approach could effectively isolate rare ECFCs by virtue of their CD34 expression. Results: We conducted preclinical experiments with peripheral blood from four adult volunteers and demonstrated that the actual microfluidic capture of circulating CD34+ cells from unprocessed blood was compatible with the subsequent differentiation of these cells into ECFCs. Moreover, the ECFC yield obtained with the microfluidic system was comparable to that of the standard method. Importantly, we unequivocally validated the phenotypical and functional properties of the captured ECFCs, including the ability to form microvascular networks following transplantation into immunodeficient mice. Discussion: We showed that the simplicity and versatility of our microfluidic system could be very instrumental for ECFC isolation while preserving their therapeutic potential. We anticipate our results will facilitate additional development of clinically suitable microfluidic devices by the vascular therapeutic and diagnostic industry. PMID:25091645

  18. Systemic Vascular Function Is Associated with Muscular Power in Older Adults

    PubMed Central

    Heffernan, Kevin S.; Chalé, Angela; Hau, Cynthia; Cloutier, Gregory J.; Phillips, Edward M.; Warner, Patrick; Nickerson, Heather; Reid, Kieran F.; Kuvin, Jeffrey T.; Fielding, Roger A.

    2012-01-01

    Age-associated loss of muscular strength and muscular power is a critical determinant of loss of physical function and progression to disability in older adults. In this study, we examined the association of systemic vascular function and measures of muscle strength and power in older adults. Measures of vascular endothelial function included brachial artery flow-mediated dilation (FMD) and the pulse wave amplitude reactive hyperemia index (PWA-RHI). Augmentation index (AIx) was taken as a measure of systemic vascular function related to arterial stiffness and wave reflection. Measures of muscular strength included one repetition maximum (1RM) for a bilateral leg press. Peak muscular power was measured during 5 repetitions performed as fast as possible for bilateral leg press at 40% 1RM. Muscular power was associated with brachial FMD (r = 0.43, P < 0.05), PWA-RHI (r = 0.42, P < 0.05), and AIx (r = −0.54, P < 0.05). Muscular strength was not associated with any measure of vascular function. In conclusion, systemic vascular function is associated with lower-limb muscular power but not muscular strength in older adults. Whether loss of muscular power with aging contributes to systemic vascular deconditioning or vascular dysfunction contributes to decrements in muscular power remains to be determined. PMID:22966457

  19. In vivo characterization of regenerative peripheral nerve interface function

    NASA Astrophysics Data System (ADS)

    Ursu, Daniel C.; Urbanchek, Melanie G.; Nedic, Andrej; Cederna, Paul S.; Gillespie, R. Brent

    2016-04-01

    Objective. Regenerative peripheral nerve interfaces (RPNIs) are neurotized free autologous muscle grafts equipped with electrodes to record myoelectric signals for prosthesis control. Viability of rat RPNI constructs have been demonstrated using evoked responses. In vivo RPNI characterization is the next critical step for assessment as a control modality for prosthetic devices. Approach. Two RPNIs were created in each of two rats by grafting portions of free muscle to the ends of divided peripheral nerves (peroneal in the left and tibial in the right hind limb) and placing bipolar electrodes on the graft surface. After four months, we examined in vivo electromyographic signal activity and compared these signals to muscular electromyographic signals recorded from autologous muscles in two rats serving as controls. An additional group of two rats in which the autologous muscles were denervated served to quantify cross-talk in the electrode recordings. Recordings were made while rats walked on a treadmill and a motion capture system tracked the hind limbs. Amplitude and periodicity of signals relative to gait were quantified, correlation between electromyographic and motion recording were assessed, and a decoder was trained to predict joint motion. Main Results. Raw RPNI signals were active during walking, with amplitudes of 1 mVPP, and quiet during standing, with amplitudes less than 0.1 mVPP. RPNI signals were periodic and entrained with gait. A decoder predicted bilateral ankle motion with greater than 80% reliability. Control group signal activity agreed with literature. Denervated group signals remained quiescent throughout all evaluations. Significance. In vivo myoelectric RPNI activity encodes neural activation patterns associated with gait. Signal contamination from muscles adjacent to the RPNI is minimal, as demonstrated by the low amplitude signals obtained from the Denervated group. The periodicity and entrainment to gait of RPNI recordings suggests the

  20. The plant vascular system: Evolution, development and functions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The emergence of the tracheophyte-based vascular system of land plants had major impacts on the evolution of terrestrial biology, in general, through its role in facilitating the development of plants with increased stature, photosynthetic output, and ability to colonize a greatly expanded range of ...

  1. Imaging of vascular dynamics within the foot using dynamic diffuse optical tomography to diagnose peripheral arterial disease

    NASA Astrophysics Data System (ADS)

    Khalil, M. A.; Kim, H. K.; Hoi, J. W.; Kim, I.; Dayal, R.; Shrikande, G.; Hielscher, A. H.

    2013-03-01

    Peripheral Arterial Disease (PAD) is the narrowing of the functional area of the artery generally due to atherosclerosis. It affects between 8-12 million people in the United States and if untreated this can lead to ulceration, gangrene and ultimately amputation. The current diagnostic method for PAD is the ankle-brachial index (ABI). The ABI is a ratio of the patient's systolic blood pressure in the foot to that of the brachial artery in the arm, a ratio below 0.9 is indicative of affected vasculature. However, this method is ineffective in patients with calcified arteries (diabetic and end-stage renal failure patients), which falsely elevates the ABI recording resulting in a false negative reading. In this paper we present our results in a pilot study to deduce optical tomography's ability to detect poor blood perfusion in the foot. We performed an IRB approved 30 patient study, where we imaged the feet of the enrolled patients during a five stage dynamic imaging sequence. The patients were split up into three groups: 10 healthy subjects, 10 PAD patients and 10 PAD patients with diabetes and they were imaged while applying a pressure cuff to their thigh. Differences in the magnitude of blood pooling in the foot and rate at which the blood pools in the foot are all indicative of arterial disease.

  2. Dual-mode imaging of cutaneous tissue oxygenation and vascular function.

    PubMed

    Xu, Ronald X; Huang, Kun; Qin, Ruogu; Huang, Jiwei; Xu, Jeff S; Ding, Liya; Gnyawali, Urmila S; Gordillo, Gayle M; Gnyawali, Surya C; Sen, Chandan K

    2010-01-01

    Accurate assessment of cutaneous tissue oxygenation and vascular function is important for appropriate detection, staging, and treatment of many health disorders such as chronic wounds. We report the development of a dual-mode imaging system for non-invasive and non-contact imaging of cutaneous tissue oxygenation and vascular function. The imaging system integrated an infrared camera, a CCD camera, a liquid crystal tunable filter and a high intensity fiber light source. A Labview interface was programmed for equipment control, synchronization, image acquisition, processing, and visualization. Multispectral images captured by the CCD camera were used to reconstruct the tissue oxygenation map. Dynamic thermographic images captured by the infrared camera were used to reconstruct the vascular function map. Cutaneous tissue oxygenation and vascular function images were co-registered through fiduciary markers. The performance characteristics of the dual-mode image system were tested in humans. PMID:21178967

  3. Peripheral monocytes are functionally altered and invade the CNS in ALS patients.

    PubMed

    Zondler, Lisa; Müller, Kathrin; Khalaji, Samira; Bliederhäuser, Corinna; Ruf, Wolfgang P; Grozdanov, Veselin; Thiemann, Meinolf; Fundel-Clemes, Katrin; Freischmidt, Axel; Holzmann, Karlheinz; Strobel, Benjamin; Weydt, Patrick; Witting, Anke; Thal, Dietmar R; Helferich, Anika M; Hengerer, Bastian; Gottschalk, Kay-Eberhard; Hill, Oliver; Kluge, Michael; Ludolph, Albert C; Danzer, Karin M; Weishaupt, Jochen H

    2016-09-01

    Amyotrophic lateral sclerosis (ALS) is a devastating progressive neurodegenerative disease affecting primarily the upper and lower motor neurons. A common feature of all ALS cases is a well-characterized neuroinflammatory reaction within the central nervous system (CNS). However, much less is known about the role of the peripheral immune system and its interplay with CNS resident immune cells in motor neuron degeneration. Here, we characterized peripheral monocytes in both temporal and spatial dimensions of ALS pathogenesis. We found the circulating monocytes to be deregulated in ALS regarding subtype constitution, function and gene expression. Moreover, we show that CNS infiltration of peripheral monocytes correlates with improved motor neuron survival in a genetic ALS mouse model. Furthermore, application of human immunoglobulins or fusion proteins containing only the human Fc, but not the Fab antibody fragment, increased CNS invasion of peripheral monocytes and delayed the disease onset. Our results underline the importance of peripheral monocytes in ALS pathogenesis and are in agreement with a protective role of monocytes in the early phase of the disease. The possibility to boost this beneficial function of peripheral monocytes by application of human immunoglobulins should be evaluated in clinical trials. PMID:26910103

  4. Tie1 controls angiopoietin function in vascular remodeling and inflammation.

    PubMed

    Korhonen, Emilia A; Lampinen, Anita; Giri, Hemant; Anisimov, Andrey; Kim, Minah; Allen, Breanna; Fang, Shentong; D'Amico, Gabriela; Sipilä, Tuomas J; Lohela, Marja; Strandin, Tomas; Vaheri, Antti; Ylä-Herttuala, Seppo; Koh, Gou Young; McDonald, Donald M; Alitalo, Kari; Saharinen, Pipsa

    2016-09-01

    The angiopoietin/Tie (ANG/Tie) receptor system controls developmental and tumor angiogenesis, inflammatory vascular remodeling, and vessel leakage. ANG1 is a Tie2 agonist that promotes vascular stabilization in inflammation and sepsis, whereas ANG2 is a context-dependent Tie2 agonist or antagonist. A limited understanding of ANG signaling mechanisms and the orphan receptor Tie1 has hindered development of ANG/Tie-targeted therapeutics. Here, we determined that both ANG1 and ANG2 binding to Tie2 increases Tie1-Tie2 interactions in a β1 integrin-dependent manner and that Tie1 regulates ANG-induced Tie2 trafficking in endothelial cells. Endothelial Tie1 was essential for the agonist activity of ANG1 and autocrine ANG2. Deletion of endothelial Tie1 in mice reduced Tie2 phosphorylation and downstream Akt activation, increased FOXO1 nuclear localization and transcriptional activation, and prevented ANG1- and ANG2-induced capillary-to-venous remodeling. However, in acute endotoxemia, the Tie1 ectodomain that is responsible for interaction with Tie2 was rapidly cleaved, ANG1 agonist activity was decreased, and autocrine ANG2 agonist activity was lost, which led to suppression of Tie2 signaling. Tie1 cleavage also occurred in patients with hantavirus infection. These results support a model in which Tie1 directly interacts with Tie2 to promote ANG-induced vascular responses under noninflammatory conditions, whereas in inflammation, Tie1 cleavage contributes to loss of ANG2 agonist activity and vascular stability. PMID:27548530

  5. Antenatal Hypoxia and Pulmonary Vascular Function and Remodeling

    PubMed Central

    Papamatheakis, Demosthenes G.; Blood, Arlin B.; Kim, Joon H.; Wilson, Sean M.

    2015-01-01

    This review provides evidence that antenatal hypoxia, which represents a significant and worldwide problem, causes prenatal programming of the lung. A general overview of lung development is provided along with some background regarding transcriptional and signaling systems of the lung. The review illustrates that antenatal hypoxic stress can induce a continuum of responses depending on the species examined. Fetuses and newborns of certain species and specific human populations are well acclimated to antenatal hypoxia. However, antenatal hypoxia causes pulmonary vascular disease in fetuses and newborns of most mammalian species and humans. Disease can range from mild pulmonary hypertension, to severe vascular remodeling and dangerous elevations in pressure. The timing, length, and magnitude of the intrauterine hypoxic stress are important to disease development, however there is also a genetic-environmental relationship that is not yet completely understood. Determining the origins of pulmonary vascular remodeling and pulmonary hypertension and their associated effects is a challenging task, but is necessary in order to develop targeted therapies for pulmonary hypertension in the newborn due to antenatal hypoxia that can both treat the symptoms and curtail or reverse disease progression. PMID:24063380

  6. Vascular and cognitive functions associated with cardiovascular disease in the elderly

    PubMed Central

    Cohen, Ronald A.; Poppas, Athena; Forman, Daniel E.; Hoth, Karin F.; Haley, Andreana P.; Gunstad, John; Jefferson, Angela L.; Tate, David F.; Paul, Robert H.; Sweet, Lawrence H.; Ono, Mokato; Jerskey, Beth A.; Gerhard-Herman, Marie

    2009-01-01

    This study examines the relationship between systemic vascular function, neurocognitive performance, and structural brain abnormalities on magnetic resonance imaging (MRI) among geriatric outpatients with treated, stable cardiovascular disease and no history of neurological illness (n = 88, ages 56–85 years). Vascular function was assessed by cardiac ejection fraction and output, sequential systolic and diastolic blood pressures, flow mediated brachial artery reactivity (BAR), and carotid intima media thickness (IMT). White matter hyperintensities (WMH) on MRI were quantified and examined relative to cognitive and vascular function. Principal component analysis revealed two primary vascular components: one associated with cardiac function, the other with atherosclerotic burden/endothelial dysfunction. Both factors were significantly associated with cognitive function and WMH volume. Reduced systolic variability and increased IMT were most strongly related to reduced attention, executive function, and information-processing speed. These findings suggest the possibility that systemic vascular indices may provide proxy measures of cerebrovascular dysfunction and reinforce the importance of achieving greater understanding of interaction between systemic vascular disease and brain dysfunction among elderly people with cardiovascular disease. PMID:18608677

  7. A single portion of blueberry (Vaccinium corymbosum L) improves protection against DNA damage but not vascular function in healthy male volunteers.

    PubMed

    Del Bó, Cristian; Riso, Patrizia; Campolo, Jonica; Møller, Peter; Loft, Steffen; Klimis-Zacas, Dorothy; Brambilla, Ada; Rizzolo, Anna; Porrini, Marisa

    2013-03-01

    It has been suggested that anthocyanin-rich foods may exert antioxidant effects and improve vascular function as demonstrated mainly in vitro and in the animal model. Blueberries are rich sources of anthocyanins and we hypothesized that their intake could improve cell protection against oxidative stress and affect endothelial function in humans. The aim of the study was to investigate the effect of one portion (300 g) of blueberries on selected markers of oxidative stress and antioxidant protection (endogenous and oxidatively induced DNA damage) and of vascular function (changes in peripheral arterial tone and plasma nitric oxide levels) in male subjects. In a randomized cross-over design, separated by a wash out period ten young volunteers received one portion of blueberries ground by blender or one portion of a control jelly. Before and after consumption (at 1, 2, and 24 hours), blood samples were collected and used to evaluate anthocyanin absorption (through mass spectrometry), endogenous and H(2)O(2)-induced DNA damage in blood mononuclear cells (through the comet assay), and plasma nitric oxide concentrations (through a fluorometric assay). Peripheral arterial function was assessed by means of Endo-PAT 2000. Blueberries significantly reduced (P < .01) H(2)O(2)-induced DNA damage (-18%) 1 hour after blueberry consumption compared to control. No significant differences were observed for endogenous DNA damage, peripheral arterial function and nitric oxide levels after blueberry intake. In conclusion, one portion of blueberries seems sufficient to improve cell antioxidant defense against DNA damage, but further studies are necessary to understand their role on vascular function. PMID:23507228

  8. Interference with PPARγ Function in Smooth Muscle Causes Vascular Dysfunction and Hypertension

    PubMed Central

    Halabi, Carmen M.; Beyer, Andreas M.; de Lange, Willem J.; Keen, Henry L.; Baumbach, Gary L.; Faraci, Frank M.; Sigmund, Curt D.

    2008-01-01

    Summary Peroxisome proliferator-activated receptor-γ (PPARγ) is a ligand activated transcription factor playing a critical role in metabolism. Thiazolidinediones, high affinity PPARγ ligands used clinically to treat type-II diabetes, have been reported to lower blood pressure and provide other cardiovascular benefits. Some mutations in PPARγ cause type-II diabetes and severe hypertension. We tested the hypothesis that PPARγ in vascular muscle plays a role in the regulation of vascular tone and blood pressure. Transgenic mice expressing dominant negative mutations in PPARγ under the control of a smooth muscle-specific promoter exhibit a loss of responsiveness to nitric oxide and striking alterations in contractility in the aorta, hypertrophy and inward remodeling in the cerebral microcirculation, and systolic hypertension. These results identify PPARγ as pivotal in vascular muscle as a regulator of vascular structure, vascular function and blood pressure, potentially explaining some of the cardioprotective effects of thiazolidinediones. PMID:18316027

  9. Biomechanical regulation of vascular smooth muscle cell functions: from in vitro to in vivo understanding

    PubMed Central

    Qiu, Juhui; Zheng, Yiming; Hu, Jianjun; Liao, Donghua; Gregersen, Hans; Deng, Xiaoyan; Fan, Yubo; Wang, Guixue

    2014-01-01

    Vascular smooth muscle cells (VSMCs) have critical functions in vascular diseases. Haemodynamic factors are important regulators of VSMC functions in vascular pathophysiology. VSMCs are physiologically active in the three-dimensional matrix and interact with the shear stress sensor of endothelial cells (ECs). The purpose of this review is to illustrate how haemodynamic factors regulate VSMC functions under two-dimensional conditions in vitro or three-dimensional co-culture conditions in vivo. Recent advances show that high shear stress induces VSMC apoptosis through endothelial-released nitric oxide and low shear stress upregulates VSMC proliferation and migration through platelet-derived growth factor released by ECs. This differential regulation emphasizes the need to construct more actual environments for future research on vascular diseases (such as atherosclerosis and hypertension) and cardiovascular tissue engineering. PMID:24152813

  10. Peripheral blood lymphocyte phenotype and function in multiple sclerosis.

    PubMed Central

    Hughes, P J; Compston, D A

    1988-01-01

    T suppressor cell function and phenotype are abnormal in patients with multiple sclerosis, especially during the chronic progressive phase but the sub-populations defined by mitogen stimulation and serological methods may not be identical. In this study, involving 45 patients with multiple sclerosis and 33 controls, there was no correlation between T suppressor function and CD8 cell phenotype in patients with multiple sclerosis or in controls. These phenotypic and functional studies cannot therefore be used interchangeably in the assessment of patients with multiple sclerosis since they provide different information about lymphocyte subpopulations. PMID:2976082

  11. Regulation of macrophage development and function in peripheral tissues

    PubMed Central

    Lavin, Yonit; Mortha, Arthur; Rahman, Adeeb; Merad, Miriam

    2015-01-01

    Macrophages are immune cells of haematopoietic origin that provide crucial innate immune defence and have tissue-specific functions in the regulation and maintenance of organ homeostasis. Recent studies of macrophage ontogeny, as well as transcriptional and epigenetic identity, have started to reveal the decisive role of the tissue stroma in the regulation of macrophage function. These findings suggest that most macrophages seed the tissues during embryonic development and functionally specialize in response to cytokines and metabolites that are released by the stroma and drive the expression of unique transcription factors. In this Review, we discuss how recent insights into macrophage ontogeny and macrophage–stroma interactions contribute to our understanding of the crosstalk that shapes macrophage function and the maintenance of organ integrity. PMID:26603899

  12. Association between smoking status and the parameters of vascular structure and function in adults: results from the EVIDENT study

    PubMed Central

    2013-01-01

    Background The present study analyses the relation between smoking status and the parameters used to assess vascular structure and function. Methods This cross-sectional, multi-centre study involved a random sample of 1553 participants from the EVIDENT study. Measurements: The smoking status, peripheral augmentation index and ankle-brachial index were measured in all participants. In a small subset of the main population (265 participants), the carotid intima-media thickness and pulse wave velocity were also measured. Results After controlling for the effect of age, sex and other risk factors, present smokers have higher values of carotid intima-media thickness (p = 0.011). Along the same lines, current smokers have higher values of pulse wave velocity and lower mean values of ankle-brachial index but without statistical significance in both cases. Conclusions Among the parameters of vascular structure and function analysed, only the IMT shows association with the smoking status, after adjusting for confounders. PMID:24289208

  13. Creating Perfused Functional Vascular Channels Using 3D Bio-Printing Technology

    PubMed Central

    Lee, Vivian K.; Kim, Diana Y.; Ngo, Haygan; Lee, Young; Seo, Lan; Yoo, Seung-Schik; Vincent, Peter A.; Dai, Guohao

    2014-01-01

    We developed a methodology using 3D bio-printing technology to create a functional in vitro vascular channel with perfused open lumen using only cells and biological matrices. The fabricated vasculature has a tight, confluent endothelium lining, presenting barrier function for both plasma protein and high-molecular weight dextran molecule. The fluidic vascular channel is capable of supporting the viability of tissue up to 5mm in distance at 5 million cells/mL density under the physiological flow condition. In static-cultured vascular channels, active angiogenic sprouting from the vessel surface was observed whereas physiological flow strongly suppressed this process. Gene expression analysis were reported in this study to show the potential of this vessel model in vascular biology research. The methods have great potential in vascularized tissue fabrication using 3D bio-printing technology as the vascular channel is simultaneously created while cells and matrix are printed around the channel in desired 3D patterns. It can also serve as a unique experimental tool for investigating fundamental mechanisms of vascular remodeling with extracellular matrix and maturation process under 3D flow condition. PMID:24965886

  14. Creating perfused functional vascular channels using 3D bio-printing technology.

    PubMed

    Lee, Vivian K; Kim, Diana Y; Ngo, Haygan; Lee, Young; Seo, Lan; Yoo, Seung-Schik; Vincent, Peter A; Dai, Guohao

    2014-09-01

    We developed a methodology using 3D bio-printing technology to create a functional in vitro vascular channel with perfused open lumen using only cells and biological matrices. The fabricated vasculature has a tight, confluent endothelium lining, presenting barrier function for both plasma protein and high-molecular weight dextran molecule. The fluidic vascular channel is capable of supporting the viability of tissue up to 5 mm in distance at 5 million cells/mL density under the physiological flow condition. In static-cultured vascular channels, active angiogenic sprouting from the vessel surface was observed whereas physiological flow strongly suppressed this process. Gene expression analysis was reported in this study to show the potential of this vessel model in vascular biology research. The methods have great potential in vascularized tissue fabrication using 3D bio-printing technology as the vascular channel is simultaneously created while cells and matrix are printed around the channel in desired 3D patterns. It can also serve as a unique experimental tool for investigating fundamental mechanisms of vascular remodeling with extracellular matrix and maturation process under 3D flow condition. PMID:24965886

  15. Small-diameter biodegradable scaffolds for functional vascular tissue engineering in the mouse model.

    PubMed

    Roh, Jason D; Nelson, Gregory N; Brennan, Matthew P; Mirensky, Tamar L; Yi, Tai; Hazlett, Tyrone F; Tellides, George; Sinusas, Albert J; Pober, Jordan S; Saltzman, W M; Kyriakides, Themis R; Breuer, Christopher K

    2008-04-01

    The development of neotissue in tissue engineered vascular grafts remains poorly understood. Advances in mouse genetic models have been highly informative in the study of vascular biology, but have been inaccessible to vascular tissue engineers due to technical limitations on the use of mouse recipients. To this end, we have developed a method for constructing sub-1mm internal diameter (ID) biodegradable scaffolds utilizing a dual cylinder chamber molding system and a hybrid polyester sealant scaled for use in a mouse model. Scaffolds constructed from either polyglycolic acid or poly-l-lactic acid nonwoven felts demonstrated sufficient porosity, biomechanical profile, and biocompatibility to function as vascular grafts. The scaffolds implanted as either inferior vena cava or aortic interposition grafts in SCID/bg mice demonstrated excellent patency without evidence of thromboembolic complications or aneurysm formation. A foreign body immune response was observed with marked macrophage infiltration and giant cell formation by post-operative week 3. Organized vascular neotissue, consisting of endothelialization, medial generation, and collagen deposition, was evident within the internal lumen of the scaffolds by post-operative week 6. These results present the ability to create sub-1mm ID biodegradable tubular scaffolds that are functional as vascular grafts, and provide an experimental approach for the study of vascular tissue engineering using mouse models. PMID:18164056

  16. Association of digital vascular function with cardiovascular risk factors: a population study

    PubMed Central

    Kuznetsova, Tatiana; Van Vlierberghe, Eline; Knez, Judita; Szczesny, Gregory; Thijs, Lutgarde; Jozeau, Dominique; Balestra, Costantino; D'hooge, Jan; Staessen, Jan A

    2014-01-01

    Objectives Vasodilation of the peripheral arteries during reactive hyperaemia depends in part on release of nitric oxide from endothelial cells. Previous studies mainly employed a fingertip tonometric device to derive pulse wave amplitude (PWA) and PWA hyperaemic changes. An alternative approach is based on photoplethysmography (PPG). We sought to evaluate the correlates of digital PPG PWA hyperaemic responses as a measure of peripheral vascular function. Design The Flemish Study on Environment, Genes and Health Outcomes (FLEMENGHO) is a population-based cohort study. Setting Respondents were examined at one centre in northern Belgium. Participants For this analysis, our sample consisted of 311 former participants (53.5% women; mean age 52.6 years; 43.1% hypertensive), who were examined from January 2010 until March 2012 (response rate 85.1%). Primary outcome measures Using a fingertip PPG device, we measured digital PWA at baseline and at 30 s intervals for 4 min during reactive hyperaemia induced by a 5 min forearm cuff occlusion. We performed stepwise regression to identify correlates of the hyperaemic response ratio for each 30 s interval after cuff deflation. Results The maximal hyperaemic response was detected in the 30–60 s interval. The explained variance for the PPG PWA ratio ranged from 9.7% at 0–30 s interval to 22.5% at 60–90 s time interval. The hyperaemic response at each 30 s interval was significantly higher in women compared with men (p≤0.001). The PPG PWA changes at 0–90 s intervals decreased with current smoking (p≤0.0007) and at 0–240 s intervals decreased with higher body mass index (p≤0.035). These associations with sex, current smoking and body mass index were mutually independent. Conclusions Our study is the first to implement the new PPG technique to measure digital PWA hyperaemic changes in a general population. Hyperaemic response, as measured by PPG, is inversely associated with traditional

  17. Vascular quality of care pilot study: how admission to a vascular surgery service affects evidence-based pharmacologic risk factor modification in patients with lower extremity peripheral arterial disease

    PubMed Central

    Steenhof, Naomi; Le Piane, Francesca; Leblanc, Kori; Eisenberg, Naomi R; Kwan, Yvonne; Malmberg, Christine; Papadopoulos, Alexandra; Roche-Nagle, Graham

    2014-01-01

    Background Peripheral arterial disease (PAD) guidelines recommend aggressive risk factor modification to improve cardiovascular outcomes. Recommended pharmacologic therapies include antiplatelets, angiotensin converting enzyme (ACE) inhibitors, and HMG-CoA-reductase inhibitors (statins). Purpose We studied the degree to which patient admission to a vascular surgery service increased the use of these therapies. Patients and methods The authors conducted a retrospective chart review of 150 patients with PAD admitted to the vascular surgery service at a large Canadian tertiary care hospital. The use of recommended pharmacologic therapies at the time of admission and discharge were compared. A multidisciplinary clinical team established criteria by which patients were deemed ineligible to receive any of the recommended therapies. Angiotensin receptor blockers (ARBs) were considered an alternative to ACE inhibitors. Results Prior to hospital admission, 64% of patients were on antiplatelet therapy, 67% were on an ACE inhibitor or ARB, and 71% were on a statin. At the time of discharge, 91% of patients were on an antiplatelet (or not, with an acceptable reason), 77% were on an ACE inhibitor or an ARB (or not, with an acceptable reason), and 85% were on a statin (or not, with an acceptable reason). While new prescriptions were largely responsible for improved guideline adherence with antiplatelets and statins, most of the apparent improvement in ACE inhibitor and ARB use was the result of identifying an acceptable reason for not having them prescribed. Conclusion This hypothesis generating pilot study supports the findings of others that there is suboptimal prescription of pharmacologic risk reduction therapies in the PAD population. Admission to a vascular service increases these rates. Nevertheless, some patients are still not receiving evidence-based treatment at discharge even after consideration of acceptable reasons. Strategies are needed to improve PAD guideline

  18. Increased Expression of Tissue Factor and Receptor for Advanced Glycation End Products in Peripheral Blood Mononuclear Cells of Patients With Type 2 Diabetes Mellitus with Vascular Complications

    PubMed Central

    Buchs, A. E.; Kornberg, A.; Zahavi, M.; Aharoni, D.; Zarfati, C.; Rapoport, M. J.

    2004-01-01

    The aim of the study was to determine the correlation between the expression of tissue factor (TF) and the receptor for advanced glycation end products (RAGEs) and vascular complications in patients with longstanding uncontrolled type 2 diabetes (T2D). TF and RAGE mRNAs as well as TF antigen and activity were investigated in 21 T2D patients with and without vascular complications. mRNA expression was assessed by reverse transcriptase–polymerase chain reaction (RT-PCR) in nonstimulated and advanced glycation end product (AGE) albumin–stimulated peripheral blood mononuclear cells (PBMCs). TF antigen expression was determined by enzyme-linked immunosorbent assay (ELISA) and TF activity by a modified prothrombin time assay. Basal RAGE mRNA expression was 0.2 ± 0.06 in patients with complications and 0.05 ± 0.06 patients without complications (P = .004). Stimulation did not cause any further increase in either group. TF mRNA was 0.58 ± 0.29 in patients with complications and 0.21 ± 0.18 in patients without complications (P = .003). Stimulation resulted in a nonsignificant increase in both groups. Basal TF activity (U/106 PBMCs) was 18.4 ± 13.2 in patients with complications and 6.96 ± 5.2 in patients without complications (P = .003). It increased 3-fold in both groups after stimulation (P = .001). TF antigen (pg/106 PBMCs) was 33.7 ± 28.6 in patients with complications, 10.4 ± 7.8 in patients without complications (P = .02). Stimulation tripled TF antigen in both groups of patients (P = .001). The RAGE/TF axis is up-regulated inT2Dpatients with vascular complications as compared to patients without complications. This suggests a role for this axis in the pathogenesis of vascular complications in T2D. PMID:15203887

  19. Characterization of peripheral blood and pulmonary leukocyte function in healthy foals.

    PubMed

    Flaminio, M J; Rush, B R; Davis, E G; Hennessy, K; Shuman, W; Wilkerson, M J

    2000-03-15

    Studies in infants and foals indicate an age-dependent maturation of peripheral lymphocyte subsets. The age-dependent relationship for maturation of cellular immune responses, such as phagocytosis and lymphocyte responses of the peripheral and pulmonary-derived leukocytes, has not been characterized in foals. Lymphocyte subpopulations, mitogen stimulation response of lymphocytes, lymphokine-activated killing cell activity, phagocytosis and oxidative burst activity, and serum immunoglobulin (Ig) classes G and M concentrations were determined in developing foals. This study illustrates age-dependent changes in immunoglobulin class concentrations, lymphocyte subsets, and EqMHC Class II expression in cells of the peripheral blood and lungs of developing neonatal-to-weanling foals. The increase in peripheral blood and BAL B-lymphocytes and serum immunoglobulins in developing foals suggests expansion of immune cell populations during a time in which environmental pathogen exposure is great. General immune function, mitogenic responses, LAK cell activity, opsonized phagocytosis, and oxidative burst activity of newborns was similar to the adult horse. Total immune-cell numbers, rather than function, seemed to be the limiting factor in the development of the equine neonatal immune system. There was an age-related percent increase in the appearance of pulmonary lymphocytes, but a percent decrease in macrophages. Although development of the respiratory immune system follows changes in the peripheral blood, cellular expansion, activation, and migration may occur at a slower pace, making the respiratory environment susceptible to pathogens prior to optimal immune system maturity. PMID:10713340

  20. Potassium Channels in Peripheral Pain Pathways: Expression, Function and Therapeutic Potential

    PubMed Central

    Du, Xiaona; Gamper, Nikita

    2013-01-01

    Electrical excitation of peripheral somatosensory nerves is a first step in generation of most pain signals in mammalian nervous system. Such excitation is controlled by an intricate set of ion channels that are coordinated to produce a degree of excitation that is proportional to the strength of the external stimulation. However, in many disease states this coordination is disrupted resulting in deregulated peripheral excitability which, in turn, may underpin pathological pain states (i.e. migraine, neuralgia, neuropathic and inflammatory pains). One of the major groups of ion channels that are essential for controlling neuronal excitability is potassium channel family and, hereby, the focus of this review is on the K+ channels in peripheral pain pathways. The aim of the review is threefold. First, we will discuss current evidence for the expression and functional role of various K+ channels in peripheral nociceptive fibres. Second, we will consider a hypothesis suggesting that reduced functional activity of K+ channels within peripheral nociceptive pathways is a general feature of many types of pain. Third, we will evaluate the perspectives of pharmacological enhancement of K+ channels in nociceptive pathways as a strategy for new analgesic drug design. PMID:24396338

  1. Modular Small Diameter Vascular Grafts with Bioactive Functionalities

    PubMed Central

    Neufurth, Meik; Wang, Xiaohong; Tolba, Emad; Dorweiler, Bernhard; Schröder, Heinz C.; Link, Thorben; Diehl-Seifert, Bärbel; Müller, Werner E. G.

    2015-01-01

    We report the fabrication of a novel type of artificial small diameter blood vessels, termed biomimetic tissue-engineered blood vessels (bTEBV), with a modular composition. They are composed of a hydrogel scaffold consisting of two negatively charged natural polymers, alginate and a modified chitosan, N,O-carboxymethyl chitosan (N,O-CMC). Into this biologically inert scaffold two biofunctionally active biopolymers are embedded, inorganic polyphosphate (polyP) and silica, as well as gelatin which exposes the cell recognition signal, Arg-Gly-Asp (RGD). These materials can be hardened by exposure to Ca2+ through formation of Ca2+ bridges between the polyanions, alginate, N,O-CMC, and polyP (alginate-Ca2+-N,O-CMC-polyP). The bTEBV are formed by pressing the hydrogel through an extruder into a hardening solution, containing Ca2+. In this universal scaffold of the bTEBV biomaterial, polycations such as poly(l-Lys), poly(d-Lys) or a His/Gly-tagged RGD peptide (three RGD units) were incorporated, which promote the adhesion of endothelial cells to the vessel surface. The mechanical properties of the biopolymer material (alginate-Ca2+-N,O-CMC-polyP-silica) revealed a hardness (elastic modulus) of 475 kPa even after a short incubation period in CaCl2 solution. The material of the artificial vascular grafts (bTEBVs with an outer size 6 mm and 1.8 mm, and an inner diameter 4 mm and 0.8 mm, respectively) turned out to be durable in 4-week pulsatile flow experiments at an alternating pressure between 25 and 100 mbar (18.7 and 75.0 mm Hg). The burst pressure of the larger (smaller) vessels was 850 mbar (145 mbar). Incorporation of polycationic poly(l-Lys), poly(d-Lys), and especially the His/Gly-tagged RGD peptide, markedly increased the adhesion of human, umbilical vein/vascular endothelial cells, EA.HY926 cells, to the surface of the hydrogel. No significant effect of the polyP samples on the clotting of human plasma is measured. We propose that the metabolically degradable

  2. Peripheral Chemoreceptors: Function and Plasticity of the Carotid Body

    PubMed Central

    Kumar, Prem; Prabhakar, Nanduri R.

    2014-01-01

    The discovery of the sensory nature of the carotid body dates back to the beginning of the 20th century. Following these seminal discoveries, research into carotid body mechanisms moved forward progressively through the 20th century, with many descriptions of the ultrastructure of the organ and stimulus-response measurements at the level of the whole organ. The later part of 20th century witnessed the first descriptions of the cellular responses and electrophysiology of isolated and cultured type I and type II cells, and there now exist a number of testable hypotheses of chemotransduction. The goal of this article is to provide a comprehensive review of current concepts on sensory transduction and transmission of the hypoxic stimulus at the carotid body with an emphasis on integrating cellular mechanisms with the whole organ responses and highlighting the gaps or discrepancies in our knowledge. It is increasingly evident that in addition to hypoxia, the carotid body responds to a wide variety of blood-borne stimuli, including reduced glucose and immune-related cytokines and we therefore also consider the evidence for a polymodal function of the carotid body and its implications. It is clear that the sensory function of the carotid body exhibits considerable plasticity in response to the chronic perturbations in environmental O2 that is associated with many physiological and pathological conditions. The mechanisms and consequences of carotid body plasticity in health and disease are discussed in the final sections of this article. PMID:23728973

  3. Gpr116 Receptor Regulates Distinctive Functions in Pneumocytes and Vascular Endothelium

    PubMed Central

    Niaudet, Colin; Vanlandewijck, Michael; Ekvärn, Elisabet; Salvado, M. Dolores; Mehlem, Annika; Al Sayegh, Sahar; He, Liqun; Lebouvier, Thibaud; Castro-Freire, Marco; Katayama, Kan; Hultenby, Kjell; Moessinger, Christine; Tannenberg, Philip; Cunha, Sara; Pietras, Kristian; Laviña, Bàrbara; Hong, JongWook; Berg, Tove; Betsholtz, Christer

    2015-01-01

    Despite its known expression in both the vascular endothelium and the lung epithelium, until recently the physiological role of the adhesion receptor Gpr116/ADGRF5 has remained elusive. We generated a new mouse model of constitutive Gpr116 inactivation, with a large genetic deletion encompassing exon 4 to exon 21 of the Gpr116 gene. This model allowed us to confirm recent results defining Gpr116 as necessary regulator of surfactant homeostasis. The loss of Gpr116 provokes an early accumulation of surfactant in the lungs, followed by a massive infiltration of macrophages, and eventually progresses into an emphysema-like pathology. Further analysis of this knockout model revealed cerebral vascular leakage, beginning at around 1.5 months of age. Additionally, endothelial-specific deletion of Gpr116 resulted in a significant increase of the brain vascular leakage. Mice devoid of Gpr116 developed an anatomically normal and largely functional vascular network, surprisingly exhibited an attenuated pathological retinal vascular response in a model of oxygen-induced retinopathy. These data suggest that Gpr116 modulates endothelial properties, a previously unappreciated function despite the pan-vascular expression of this receptor. Our results support the key pulmonary function of Gpr116 and describe a new role in the central nervous system vasculature. PMID:26394398

  4. Gpr116 Receptor Regulates Distinctive Functions in Pneumocytes and Vascular Endothelium.

    PubMed

    Niaudet, Colin; Hofmann, Jennifer J; Mäe, Maarja A; Jung, Bongnam; Gaengel, Konstantin; Vanlandewijck, Michael; Ekvärn, Elisabet; Salvado, M Dolores; Mehlem, Annika; Al Sayegh, Sahar; He, Liqun; Lebouvier, Thibaud; Castro-Freire, Marco; Katayama, Kan; Hultenby, Kjell; Moessinger, Christine; Tannenberg, Philip; Cunha, Sara; Pietras, Kristian; Laviña, Bàrbara; Hong, JongWook; Berg, Tove; Betsholtz, Christer

    2015-01-01

    Despite its known expression in both the vascular endothelium and the lung epithelium, until recently the physiological role of the adhesion receptor Gpr116/ADGRF5 has remained elusive. We generated a new mouse model of constitutive Gpr116 inactivation, with a large genetic deletion encompassing exon 4 to exon 21 of the Gpr116 gene. This model allowed us to confirm recent results defining Gpr116 as necessary regulator of surfactant homeostasis. The loss of Gpr116 provokes an early accumulation of surfactant in the lungs, followed by a massive infiltration of macrophages, and eventually progresses into an emphysema-like pathology. Further analysis of this knockout model revealed cerebral vascular leakage, beginning at around 1.5 months of age. Additionally, endothelial-specific deletion of Gpr116 resulted in a significant increase of the brain vascular leakage. Mice devoid of Gpr116 developed an anatomically normal and largely functional vascular network, surprisingly exhibited an attenuated pathological retinal vascular response in a model of oxygen-induced retinopathy. These data suggest that Gpr116 modulates endothelial properties, a previously unappreciated function despite the pan-vascular expression of this receptor. Our results support the key pulmonary function of Gpr116 and describe a new role in the central nervous system vasculature. PMID:26394398

  5. Ciguatoxin reduces regenerative capacity of axotomized peripheral neurons and delays functional recovery in pre-exposed mice after peripheral nerve injury.

    PubMed

    Au, Ngan Pan Bennett; Kumar, Gajendra; Asthana, Pallavi; Tin, Chung; Mak, Yim Ling; Chan, Leo Lai; Lam, Paul Kwan Sing; Ma, Chi Him Eddie

    2016-01-01

    Ciguatera fish poisoning (CFP) results from consumption of tropical reef fish containing ciguatoxins (CTXs). Pacific (P)-CTX-1 is among the most potent known CTXs and the predominant source of CFP in the endemic region responsible for the majority of neurological symptoms in patients. Chronic and persistent neurological symptoms occur in some CFP patients, which often result in incomplete functional recovery for years. However, the direct effects of exposure to CTXs remain largely unknown. In present study, we exposed mice to CTX purified from ciguatera fish sourced from the Pacific region. P-CTX-1 was detected in peripheral nerves within hours and persisted for two months after exposure. P-CTX-1 inhibited axonal regrowth from axotomized peripheral neurons in culture. P-CTX-1 exposure reduced motor function in mice within the first two weeks of exposure before returning to baseline levels. These pre-exposed animals exhibited delayed sensory and motor functional recovery, and irreversible motor deficits after peripheral nerve injury in which formation of functional synapses was impaired. These findings are consistent with reduced muscle function, as assessed by electromyography recordings. Our study provides strong evidence that the persistence of P-CTX-1 in peripheral nerves reduces the intrinsic growth capacity of peripheral neurons, resulting in delayed functional recovery after injury. PMID:27229176

  6. Ciguatoxin reduces regenerative capacity of axotomized peripheral neurons and delays functional recovery in pre-exposed mice after peripheral nerve injury

    PubMed Central

    Au, Ngan Pan Bennett; Kumar, Gajendra; Asthana, Pallavi; Tin, Chung; Mak, Yim Ling; Chan, Leo Lai; Lam, Paul Kwan Sing; Ma, Chi Him Eddie

    2016-01-01

    Ciguatera fish poisoning (CFP) results from consumption of tropical reef fish containing ciguatoxins (CTXs). Pacific (P)-CTX-1 is among the most potent known CTXs and the predominant source of CFP in the endemic region responsible for the majority of neurological symptoms in patients. Chronic and persistent neurological symptoms occur in some CFP patients, which often result in incomplete functional recovery for years. However, the direct effects of exposure to CTXs remain largely unknown. In present study, we exposed mice to CTX purified from ciguatera fish sourced from the Pacific region. P-CTX-1 was detected in peripheral nerves within hours and persisted for two months after exposure. P-CTX-1 inhibited axonal regrowth from axotomized peripheral neurons in culture. P-CTX-1 exposure reduced motor function in mice within the first two weeks of exposure before returning to baseline levels. These pre-exposed animals exhibited delayed sensory and motor functional recovery, and irreversible motor deficits after peripheral nerve injury in which formation of functional synapses was impaired. These findings are consistent with reduced muscle function, as assessed by electromyography recordings. Our study provides strong evidence that the persistence of P-CTX-1 in peripheral nerves reduces the intrinsic growth capacity of peripheral neurons, resulting in delayed functional recovery after injury. PMID:27229176

  7. Structural and Functional Changes of Peripheral Muscles in Copd Patients

    PubMed Central

    Rabinovich, Roberto A; Vilaró, Jordi

    2010-01-01

    Purpose of Review The purpose of this review is to identify new advances in our understanding of skeletal muscle dysfunction in patients with COPD. Recent findings Recent studies have confirmed the relevance of muscle dysfunction as an independent prognosis factor in COPD. Animal studies have shed light on the molecular mechanisms governing skeletal muscle hypertrophy/atrophy. Recent evidence in patients with COPD highlighted the contribution of protein breakdown and mitochondrial dysfunction as pathogenic mechanisms leading to muscle dysfunction in these patients. Summary Chronic Obstructive Pulmonary Disease (COPD) is a debilitating disease impacting negatively on health status and the functional capacity of patients. COPD goes beyond the lungs and incurs significant systemic effects among which muscle dysfunction/wasting in one of the most important. Muscle dysfunction is a prominent contributor to exercise limitation, healthcare utilization and an independent predictor of morbidity and mortality. Gaining more insight into the molecular mechanisms leading to muscle dysfunction/wasting is key for the development of new and tailored therapeutic strategies to tackle skeletal muscle dysfunction/wasting in COPD patients. PMID:20071991

  8. Genetic Pathways of Vascular Calcification

    PubMed Central

    Bowman, Marion A. Hofmann; McNally, Elizabeth M.

    2012-01-01

    Vascular calcification is an independent risk factor for cardiovascular disease. Arterial calcification of the aorta, coronary, carotid and peripheral arteries becomes more prevalent with age. Genomewide association studies have identified regions of the genome linked to vascular calcification, and these same regions are linked to myocardial infarction risk. The 9p21 region linked to vascular disease and inflammation also associates with vascular calcification. In addition to these common variants, rare genetic defects can serve as primary triggers of accelerated and premature calcification. Infancy-associated calcific disorders are caused by loss of function mutations in ENPP1 an enzyme that produces extracellular pyrophosphate. Adult onset vascular calcification is linked to mutations NTE5, another enzyme that regulates extracellular phosphate metabolism. Common conditions that secondarily enhance vascular calcification include atherosclerosis, metabolic dysfunction, diabetes, and impaired renal clearance. Oxidative stress and vascular inflammation, along with biophysical properties, converge with these predisposing factors to promote soft tissue mineralization. Vascular calcification is accompanied by an osteogenic profile, and this osteogenic conversion is seen within the vascular smooth muscle itself as well as the matrix. Herein we will review the genetic causes of medial calcification in the smooth muscle layer, focusing on recent discoveries of gene mutations that regulate extracellular matrix phosphate production and the role of S100 proteins as promoters of vascular calcification. PMID:23040839

  9. Percutaneous transluminal rotational atherectomy in the treatment of peripheral vascular disease using a transluminal endatherectomy catheter (TEC): Initial results and angiographic follow-up

    SciTech Connect

    Rilinger, Norbert; Goerich, Johannes; Scharrer-Pamler, Reinhard; Vogel, Jochen; Tomczak, Reinhard; Merkle, Elmar; Sokiranski, Roman; Brambs, Hans-Juergen

    1997-07-15

    Purpose. To evaluate the clinical results of percutaneous transluminal rotational atherectomy in the treatment of peripheral vascular disease. Methods. Rotational atherectomy was performed in 39 patients aged 39-87 years (mean 66.6 years). A total of 71 lesions (43 stenoses and 28 occlusions) were treated in 40 limbs. Additional balloon angioplasty was required in 54% of lesions. Fifteen patients (37.5%) presented in Fontaine stage II, 10 patients (25%) in Fontaine stage III and 15 patients (37.5%) in Fontaine stage IV. Rotational atherectomy at 750 rpm was carried out over a 0.014-inch guidewire with continuous aspiration into a vacuum, bottle. Follow-up angiography and color flow Doppler examinations were performed in 22 patients (23 limbs) after a mean period of 6 months (range 2-14 months). Results. There was one primary technical failure. In 36 of 40 lesions there was a good angiographic result with residual stenoses in less than 30%. In 70 lesions treated by rotational atherectomy, however, 54% showed residual stenoses of 30%-50% and these cases required additional balloon angioplasty. The mean ankle-brachial index improved significantly (p<0.001), from 0.49 before the procedure to 1.01 after the procedure. A single distal embolus, related to primary recanalization, occurred and there were two large inguinal hematomas. Cumulative clinical patency after 6 months was 83.8% and cumulative angiographic patency after 6 months was 79.1%. Conclusion. Percutaneous rotational atherectomy is a promising approach for the treatment of chronic peripheral vascular disease. Further prospective, randomized studies are necessary to compare percutaneous transluminal angioplasty with this new technical approach.

  10. Effects of cranberry juice consumption on vascular function in patients with coronary artery disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cranberry juice contains polyphenolic compounds that could improve endothelial function and reduce cardiovascular disease risk. The objective was to examine the effects of cranberry juice on vascular function in subjects with coronary artery disease. We completed an acute pilot study with no placebo...

  11. Alcohol and cardiovascular disease--modulation of vascular cell function.

    PubMed

    Cahill, Paul A; Redmond, Eileen M

    2012-04-01

    Alcohol is a commonly used drug worldwide. Epidemiological studies have identified alcohol consumption as a factor that may either positively or negatively influence many diseases including cardiovascular disease, certain cancers and dementia. Often there seems to be a differential effect of various drinking patterns, with frequent moderate consumption of alcohol being salutary and binge drinking or chronic abuse being deleterious to one's health. A better understanding of the cellular and molecular mechanisms mediating the many effects of alcohol consumption is beginning to emerge, as well as a clearer picture as to whether these effects are due to the direct actions of alcohol itself, or caused in part by its metabolites, e.g., acetaldehyde, or by incidental components present in the alcoholic beverage (e.g., polyphenols in red wine). This review will discuss evidence to date as to how alcohol (ethanol) might affect atherosclerosis that underlies cardiovascular and cerebrovascular disease, and the putative mechanisms involved, focusing on vascular endothelial and smooth muscle cell effects. PMID:22606372

  12. Age-dependent changes in Ca2+ homeostasis in peripheral neurones: implications for changes in function.

    PubMed

    Buchholz, John N; Behringer, Erik J; Pottorf, William J; Pearce, William J; Vanterpool, Conwin K

    2007-06-01

    Calcium ions represent universal second messengers within neuronal cells integrating multiple cellular functions, such as release of neurotransmitters, gene expression, proliferation, excitability, and regulation of cell death or apoptotic pathways. The magnitude, duration and shape of stimulation-evoked intracellular calcium ([Ca2+]i) transients are determined by a complex interplay of mechanisms that modulate stimulation-evoked rises in [Ca2+]i that occur with normal neuronal function. Disruption of any of these mechanisms may have implications for the function and health of peripheral neurones during the aging process. This review focuses on the impact of advancing age on the overall function of peripheral adrenergic neurones and how these changes in function may be linked to age-related changes in modulation of [Ca2+]i regulation. The data in this review suggest that normal aging in peripheral autonomic neurones is a subtle process and does not always result in dramatic deterioration in their function. We present studies that support the idea that in order to maintain cell viability peripheral neurones are able to compensate for an age-related decline in the function of at least one of the neuronal calcium-buffering systems, smooth endoplasmic reticulum calcium ATPases, by increased function of other calcium-buffering systems, namely, the mitochondria and plasmalemma calcium extrusion. Increased mitochondrial calcium uptake may represent a 'weak point' in cellular compensation as this over time may contribute to cell death. In addition, we present more recent studies on [Ca2+]i regulation in the form of the modulation of release of calcium from smooth endoplasmic reticulum calcium stores. These studies suggest that the contribution of the release of calcium from smooth endoplasmic reticulum calcium stores is altered with age through a combination of altered ryanodine receptor levels and modulation of these receptors by neuronal nitric oxide containing neurones

  13. Peripheral Blood-Derived Mesenchymal Stromal Cells Promote Angiogenesis via Paracrine Stimulation of Vascular Endothelial Growth Factor Secretion in the Equine Model.

    PubMed

    Bussche, Leen; Van de Walle, Gerlinde R

    2014-12-01

    Mesenchymal stromal cells (MSCs) have received much attention as a potential treatment of ischemic diseases, including ischemic tissue injury and cardiac failure. The beneficial effects of MSCs are thought to be mediated by their ability to provide proangiogenic factors, creating a favorable microenvironment that results in neovascularization and tissue regeneration. To study this in more detail and to explore the potential of the horse as a valuable translational model, the objectives of the present study were to examine the presence of angiogenic stimulating factors in the conditioned medium (CM) of peripheral blood-derived equine mesenchymal stromal cells (PB-MSCs) and to study their in vitro effect on angiogenesis-related endothelial cell (EC) behavior, including proliferation and vessel formation. Our salient findings were that CM from PB-MSCs contained significant levels of several proangiogenic factors. Furthermore, we found that CM could induce angiogenesis in equine vascular ECs and confirmed that endothelin-1, insulin growth factor binding protein 2, interleukin-8, and platelet-derived growth factor-AA, but not urokinase-type plasminogen activator, were responsible for this enhanced EC network formation by increasing the expression level of vascular endothelial growth factor-A, an important angiogenesis stimulator. PMID:25313202

  14. Abnormal Vascular Function and Hypertension in Mice Deficient in Estrogen Receptor β

    NASA Astrophysics Data System (ADS)

    Zhu, Yan; Bian, Zhao; Lu, Ping; Karas, Richard H.; Bao, Lin; Cox, Daniel; Hodgin, Jeffrey; Shaul, Philip W.; Thorén, Peter; Smithies, Oliver; Gustafsson, Jan-Åke; Mendelsohn, Michael E.

    2002-01-01

    Blood vessels express estrogen receptors, but their role in cardiovascular physiology is not well understood. We show that vascular smooth muscle cells and blood vessels from estrogen receptor β (ERβ)-deficient mice exhibit multiple functional abnormalities. In wild-type mouse blood vessels, estrogen attenuates vasoconstriction by an ERβ-mediated increase in inducible nitric oxide synthase expression. In contrast, estrogen augments vasoconstriction in blood vessels from ERβ-deficient mice. Vascular smooth muscle cells isolated from ERβ-deficient mice show multiple abnormalities of ion channel function. Furthermore, ERβ-deficient mice develop sustained systolic and diastolic hypertension as they age. These data support an essential role for ERβ in the regulation of vascular function and blood pressure.

  15. [Endovascular versus conventional vascular surgery - old-fashioned thinking? : Part 2: carotid artery stenosis and peripheral arterial occlusive disease].

    PubMed

    Debus, E S; Manzoni, D; Behrendt, C-A; Heidemann, F; Grundmann, R T

    2016-04-01

    Endovascular therapy has widely replaced conventional open vascular surgical reconstruction. For this reason, both techniques were widely considered to be competing approaches. Evidence-based data from randomized prospective trials, meta-analyses and clinical registries, however, demonstrated that both techniques should be used to complement each other. It became increasingly more evident that the use of either procedure depends on the underlying disease and the anatomical conditions, whereby a combination of both (hybrid approach) may be the preferred option in certain situations. This review focuses on the treatment of patients with carotid artery stenosis, intermittent claudication, critical limb ischemia and acute limb ischemia. PMID:26801751

  16. Functional defects of peripheral regulatory T lymphocytes in patients with progressive vitiligo.

    PubMed

    Ben Ahmed, M; Zaraa, I; Rekik, R; Elbeldi-Ferchiou, A; Kourda, N; Belhadj Hmida, N; Abdeladhim, M; Karoui, O; Ben Osman, A; Mokni, M; Louzir, H

    2012-01-01

    Auto-reactive cytotoxic T lymphocytes play a key role in the progressive loss or destruction of melanocytes in vitiligo but the mechanism underlying the loss of self-tolerance is unknown. A deregulation of regulatory T-cell biology has recently been suggested. The analysis of the suppressive effects of peripheral T regulatory cells in vitiligo patients revealed a functional defect in seven of 15 cases. This defect was strongly correlated with disease activity. The evaluation of the percentage of peripheral regulatory T lymphocytes did not reveal any intrinsic quantitative defect. Yet, a decrease in the percentage of such cells was noted in patients with progressive forms, suggesting a recruitment of regulatory T cells from the peripheral blood to the site of injury. This was further corroborated by the significant increase of Forkhead box P3 expression in the vitiliginous skin of patients. Our data support the involvement of a functional defect of peripheral regulatory T cells in the pathogenesis of vitiligo and open new possibilities to advance therapeutic approaches. PMID:21985183

  17. Maternal Hyperleptinemia Is Associated with Male Offspring’s Altered Vascular Function and Structure in Mice

    PubMed Central

    Pollock, Kelly E.; Talton, Omonseigho O.; Foote, Christopher A.; Reyes-Aldasoro, Constantino C.; Wu, Ho-Hsiang; Ji, Tieming; Martinez-Lemus, Luis A.; Schulz, Laura C.

    2016-01-01

    Children of mothers with gestational diabetes have greater risk of developing hypertension but little is known about the mechanisms by which this occurs. The objective of this study was to test the hypothesis that high maternal concentrations of leptin during pregnancy, which are present in mothers with gestational diabetes and/or obesity, alter blood pressure, vascular structure and vascular function in offspring. Wildtype (WT) offspring of hyperleptinemic, normoglycemic, Leprdb/+ dams were compared to genotype matched offspring of WT-control dams. Vascular function was assessed in male offspring at 6, and at 31 weeks of age after half the offspring had been fed a high fat, high sucrose diet (HFD) for 6 weeks. Blood pressure was increased by HFD but not affected by maternal hyperleptinemia. On a standard diet, offspring of hyperleptinemic dams had outwardly remodeled mesenteric arteries and an enhanced vasodilatory response to insulin. In offspring of WT but not Leprdb/+ dams, HFD induced vessel hypertrophy and enhanced vasodilatory responses to acetylcholine, while HFD reduced insulin responsiveness in offspring of hyperleptinemic dams. Offspring of hyperleptinemic dams had stiffer arteries regardless of diet. Therefore, while maternal hyperleptinemia was largely beneficial to offspring vascular health under a standard diet, it had detrimental effects in offspring fed HFD. These results suggest that circulating maternal leptin concentrations may interact with other factors in the pre- and post -natal environments to contribute to altered vascular function in offspring of diabetic pregnancies. PMID:27187080

  18. Differential and synergistic effects of mechanical stimulation and growth factor presentation on vascular wall function

    PubMed Central

    Liang, Mao-Shih; Koobatian, Maxwell T.; Lei, Pedro; Swartz, Daniel D.; Andreadis, Stelios T.

    2013-01-01

    We investigated the hypothesis that immobilizing TGF-β1 within fibrin hydrogels may act in synergy with cyclic mechanical stimulation to enhance the properties of vascular grafts. To this end, we engineered a fusion TGF-β1 protein that can covalently anchor to fibrin during polymerization upon the action of factor XIII. We also developed a 24-well based bioreactor in which vascular constructs can be mechanically stimulated by distending the silastic mandrel in the middle of each well. TGF-β1 was either conjugated to fibrin or supplied in the culture medium and the fibrin based constructs were cultured statically for a week followed by cyclic distention for another week. The tissues were examined for myogenic differentiation, vascular reactivity, mechanical properties and ECM content. Our results showed that some aspects of vascular function were differentially affected by growth factor presentation vs. pulsatile force application, while others were synergistically enhanced by both. Overall, this two-prong biomimetic approach improved ECM secretion, vascular reactivity and mechanical properties of vascular constructs. These findings may be applied in other tissue engineering applications such as cartilage, tendon or cardiac regeneration where growth factors TGF-β1 and mechano-stimulation play critical roles. PMID:23810080

  19. [Progress in research on function and mechanism of cardiac vascular system of taurine].

    PubMed

    Hua, Hao-ming; Ito, Takashi; Qiu, Zhi-gang; Azuma, Junichi

    2005-05-01

    The function for cardiac vascular system of taurine is extensive, and the mechanism is complicated. Taurine protects the cells from the cell injury caused by ischemia etc. Through repressing apoptosis, prevents endothelial dysfunction caused by hyperglycemia, hypercholesterolemia, smoking and homocysteine; suppresses the proliferation and calcification in vascular smooth muscle cells, promotes metabolization and excretion of cholesterol in the animal models of hyperlipemia, and confers the resistance to an oxidant, hypochlorous acid, produced by neutrophil on cells, and taurine chrolamine to inhibit activation of NF-kappaB, which might be associated with anti-atherosclerotic effect. Taurine mainly acts inside the cell. However, taurine transport system becomes aberrant in pathological myocardial and vascular tissue. In addition, taurine improves cardiovascular function in fructose-induced hypertension and an iron-overload murine animal models. PMID:16075725

  20. Supplementary motor area deactivation impacts the recovery of hand function from severe peripheral nerve injury

    PubMed Central

    Lu, Ye-chen; Liu, Han-qiu; Hua, Xu-yun; Shen, Yun-dong; Xu, Wen-dong; Xu, Jian-guang; Gu, Yu-dong

    2016-01-01

    Although some patients have successful peripheral nerve regeneration, a poor recovery of hand function often occurs after peripheral nerve injury. It is believed that the capability of brain plasticity is crucial for the recovery of hand function. The supplementary motor area may play a key role in brain remodeling after peripheral nerve injury. In this study, we explored the activation mode of the supplementary motor area during a motor imagery task. We investigated the plasticity of the central nervous system after brachial plexus injury, using the motor imagery task. Results from functional magnetic resonance imaging showed that after brachial plexus injury, the motor imagery task for the affected limbs of the patients triggered no obvious activation of bilateral supplementary motor areas. This result indicates that it is difficult to excite the supplementary motor areas of brachial plexus injury patients during a motor imagery task, thereby impacting brain remodeling. Deactivation of the supplementary motor area is likely to be a serious problem for brachial plexus injury patients in terms of preparing, initiating and executing certain movements, which may be partly responsible for the unsatisfactory clinical recovery of hand function. PMID:27212933

  1. Epoxyeicosatrienoic Acids and 20-Hydroxyeicosatetraenoic Acid on Endothelial and Vascular Function.

    PubMed

    Imig, J D

    2016-01-01

    Endothelial and vascular smooth cells generate cytochrome P450 (CYP) arachidonic acid metabolites that can impact endothelial cell function and vascular homeostasis. The objective of this review is to focus on the physiology and pharmacology of endothelial CYP metabolites. The CYP pathway produces two types of eicosanoid products: epoxyeicosatrienoic acids (EETs), formed by CYP epoxygenases, and hydroxyeicosatetraenoic acids (HETEs), formed by CYP hydroxylases. Advances in CYP enzymes, EETs, and 20-HETE by pharmacological and genetic means have led to a more complete understanding of how these eicosanoids impact on endothelial cell function. Endothelial-derived EETs were initially described as endothelial-derived hyperpolarizing factors. It is now well recognized that EETs importantly contribute to numerous endothelial cell functions. On the other hand, 20-HETE is the predominant CYP hydroxylase synthesized by vascular smooth muscle cells. Like EETs, 20-HETE acts on endothelial cells and impacts importantly on endothelial and vascular function. An important aspect for EETs and 20-HETE endothelial actions is their interactions with hormonal and paracrine factors. These include interactions with the renin-angiotensin system, adrenergic system, puringeric system, and endothelin. Alterations in CYP enzymes, 20-HETE, or EETs contribute to endothelial dysfunction and cardiovascular diseases such as ischemic injury, hypertension, and atherosclerosis. Recent advances have led to the development of potential therapeutics that target CYP enzymes, 20-HETE, or EETs. Thus, future investigation is required to obtain a more complete understanding of how CYP enzymes, 20-HETE, and EETs regulate endothelial cell function. PMID:27451096

  2. Generation of a functional liver tissue mimic using adipose stromal vascular fraction cell-derived vasculatures

    PubMed Central

    Nunes, S. S.; Maijub, J. G.; Krishnan, L.; Ramakrishnan, V. M.; Clayton, L. R.; Williams, S. K.; Hoying, J. B.; Boyd, N. L.

    2013-01-01

    One of the major challenges in cell implantation therapies is to promote integration of the microcirculation between the implanted cells and the host. We used adipose-derived stromal vascular fraction (SVF) cells to vascularize a human liver cell (HepG2) implant. We hypothesized that the SVF cells would form a functional microcirculation via vascular assembly and inosculation with the host vasculature. Initially, we assessed the extent and character of neovasculatures formed by freshly isolated and cultured SVF cells and found that freshly isolated cells have a higher vascularization potential. Generation of a 3D implant containing fresh SVF and HepG2 cells formed a tissue in which HepG2 cells were entwined with a network of microvessels. Implanted HepG2 cells sequestered labeled LDL delivered by systemic intravascular injection only in SVF-vascularized implants demonstrating that SVF cell-derived vasculatures can effectively integrate with host vessels and interface with parenchymal cells to form a functional tissue mimic. PMID:23828203

  3. Percutaneous intravascular US as adjunct to catheter-based interventions: preliminary experience in patients with peripheral vascular disease.

    PubMed

    Isner, J M; Rosenfield, K; Losordo, D W; Kelly, S; Palefski, P; Langevin, R E; Razvi, S; Pastore, J O; Kosowsky, B D

    1990-04-01

    Catheter-based ultrasound (US) transducers may be introduced into the vascular system to record high-resolution images of the vessel wall and lumen. The potential advantages and existing liabilities of percutaneous intravascular US as an adjunct to transluminal vascular recanalization were investigated. A 6.6-F braided, polyethylene catheter enclosing a rotary drive shaft with a single-element, 20-MHz transducer at the distal tip was used in 17 patients undergoing percutaneous transluminal (balloon) angioplasty (PTA) alone (10 patients), PTA with implantation of an endovascular stent (two patients), atherectomy alone (two patients), or laser angioplasty with PTA and/or atherectomy (three patients). The arteries treated and examined included the common iliac in five patients, the external iliac in two, the superficial femoral in nine, and a vein graft-arterial anastomosis in one. In 14 cases PTA was employed as sole or adjunctive therapy; plaque cracks were clearly delineated with intravascular US in all 14 (100%) and dissections were observed in 11 (78%). Plaque-arterial wall disruption was less prominent in the arteries treated with mechanical atherectomy. The results of laser angioplasty reflected the adjunctive modality employed. After stent implantation, serial intravascular US documented effacement of PTA-induced plaque cracks and/or dissections. Intravascular US also aided in the quantitative assessment of luminal cross-sectional areas after the procedures (19.0-51.8 mm2). The observations recorded in this preliminary group of 17 patients illustrate the potential utility of intravascular US as an adjunct to conventional angiography in patients undergoing percutaneous revascularization. PMID:2138342

  4. Age-related changes in the function and structure of the peripheral sensory pathway in mice.

    PubMed

    Canta, Annalisa; Chiorazzi, Alessia; Carozzi, Valentina Alda; Meregalli, Cristina; Oggioni, Norberto; Bossi, Mario; Rodriguez-Menendez, Virginia; Avezza, Federica; Crippa, Luca; Lombardi, Raffaella; de Vito, Giuseppe; Piazza, Vincenzo; Cavaletti, Guido; Marmiroli, Paola

    2016-09-01

    This study is aimed at describing the changes occurring in the entire peripheral nervous system sensory pathway along a 2-year observation period in a cohort of C57BL/6 mice. The neurophysiological studies evidenced significant differences in the selected time points corresponding to childhood, young adulthood, adulthood, and aging (i.e., 1, 7, 15, and 25 months of age), with a parabolic course as function of time. The pathological assessment allowed to demonstrate signs of age-related changes since the age of 7 months, with a remarkable increase in both peripheral nerves and dorsal root ganglia at the subsequent time points. These changes were mainly in the myelin sheaths, as also confirmed by the Rotating-Polarization Coherent-Anti-stokes-Raman-scattering microscopy analysis. Evident changes were also present at the morphometric analysis performed on the peripheral nerves, dorsal root ganglia neurons, and skin biopsies. This extensive, multimodal characterization of the peripheral nervous system changes in aging provides the background for future mechanistic studies allowing the selection of the most appropriate time points and readouts according to the investigation aims. PMID:27459934

  5. Peripheral nerve: from the microscopic functional unit of the axon to the biomechanically loaded macroscopic structure.

    PubMed

    Topp, Kimberly S; Boyd, Benjamin S

    2012-01-01

    Peripheral nerves are composed of motor and sensory axons, associated ensheathing Schwann cells, and organized layers of connective tissues that are in continuity with the tissues of the central nervous system. Nerve fiber anatomy facilitates conduction of electrical impulses to convey information over a distance, and the length of these polarized cells necessitates regulated axonal transport of organelles and structural proteins for normal cell function. Nerve connective tissues serve a protective function as the limb is subjected to the stresses of myriad limb positions and postures. Thus, the tissues are uniquely arranged to control the local nerve fiber environment and modulate physical stresses. In this brief review, we describe the microscopic anatomy and physiology of peripheral nerve and the biomechanical properties that enable nerve to withstand the physical stresses of everyday life. PMID:22133662

  6. Promoting plasticity in the spinal cord with chondroitinase improves functional recovery after peripheral nerve repair.

    PubMed

    Galtrey, Clare M; Asher, Richard A; Nothias, Fatiha; Fawcett, James W

    2007-04-01

    Functional recovery after peripheral nerve repair in humans is often disappointing. A major reason for this is the inaccuracy of re-innervation of muscles and sensory structures. We hypothesized that promoting plasticity in the spinal cord, through digestion of chondroitin sulphate proteoglycans (CSPGs) with chondroitinase ABC (ChABC), might allow the CNS to compensate for inaccurate peripheral re-innervation and improve functional recovery. The median and ulnar nerves were injured and repaired to produce three grades of inaccuracy of peripheral re-innervation by (i) crush of both nerves; (ii) correct repair of median to median and ulnar to ulnar; and (iii) crossover of the median and ulnar nerves. Mapping of the motor neuron pool of the flexor carpi radialis muscle showed precise re-innervation after nerve crush, inaccurate regeneration after correct repair, more inaccurate after crossover repair. Recovery of forelimb function, assessed by skilled paw reaching, grip strength and sensory testing varied with accuracy of re-innervation. This was not due to differences in the number of regenerated axons. Single injections of ChABC into the spinal cord led to long-term changes in the extracellular matrix, with hyaluronan and neurocan being removed and not fully replaced after 8 weeks. ChABC treatment produce increased sprouting visualized by MAP1BP staining and improved functional recovery in skilled paw reaching after correct repair and in grip strength after crossover repair. There was no hyperalgesia. Enhanced plasticity in the spinal cord, therefore, allows the CNS to compensate for inaccurate motor and sensory re-innervation of the periphery, and may be a useful adjunct therapy to peripheral nerve repair. PMID:17255150

  7. The role of mechanotransduction on vascular smooth muscle myocytes cytoskeleton and contractile function

    PubMed Central

    Ye, George J.C.; Nesmith, Alexander P.; Parker, Kevin Kit

    2016-01-01

    Smooth muscle exhibits a highly organized structural hierarchy that extends over multiple spatial scales to perform a wide range of functions at the cellular, tissue, and organ levels. Early efforts primarily focused on understanding vascular smooth muscle function through biochemical signaling. However, accumulating evidence suggests that mechanotransduction, the process through which cells convert mechanical stimuli into biochemical cues, is requisite for regulating contractility. Cytoskeletal proteins that comprise the extracellular, intercellular, and intracellular domains are mechanosensitive and can remodel their structure and function in response to external mechanical cues. Pathological stimuli such as malignant hypertension can act through the same mechanotransductive pathways to induce maladaptive remodeling, leading to changes in cellular shape and loss of contractile function. In both health and disease, the cytoskeletal architecture integrates the mechanical stimuli and mediates structural and functional remodeling in the vascular smooth muscle. PMID:25125187

  8. Does high-density lipoprotein protect vascular function in healthy pregnancy?

    PubMed

    Sulaiman, Wan N Wan; Caslake, Muriel J; Delles, Christian; Karlsson, Helen; Mulder, Monique T; Graham, Delyth; Freeman, Dilys J

    2016-04-01

    The maternal adaptation to pregnancy includes hyperlipidaemia, oxidative stress and chronic inflammation. In non-pregnant individuals, these processes are usually associated with poor vascular function. However, maternal vascular function is enhanced in pregnancy. It is not understood how this is achieved in the face of the adverse metabolic and inflammatory environment. Research into cardiovascular disease demonstrates that plasma HDL (high-density lipoprotein), by merit of its functionality rather than its plasma concentration, exerts protective effects on the vascular endothelium. HDL has vasodilatory, antioxidant, anti-thrombotic and anti-inflammatory effects, and can protect against endothelial cell damage. In pregnancy, the plasma HDL concentration starts to rise at 10 weeks of gestation, peaking at 20 weeks. The initial rise in plasma HDL occurs around the time of the establishment of the feto-placental circulation, a time when the trophoblast plugs in the maternal spiral arteries are released, generating oxidative stress. Thus there is the intriguing possibility that new HDL of improved function is synthesized around the time of the establishment of the feto-placental circulation. In obese pregnancy and, to a greater extent, in pre-eclampsia, plasma HDL levels are significantly decreased and maternal vascular function is reduced. Wire myography studies have shown an association between the plasma content of apolipoprotein AI, the major protein constituent of HDL, and blood vessel relaxation. These observations lead us to hypothesize that HDL concentration, and function, increases in pregnancy in order to protect the maternal vascular endothelium and that in pre-eclampsia this fails to occur. PMID:26888561

  9. [Primary Study on Noninvasive Detection of Vascular Function Based on Finger Temperature Change].

    PubMed

    Dong, Qing; Li, Xia; Wan, Yungao; Lu, Gaoquan; Wang, Xinxin; Zhang, Kuan

    2016-02-01

    By studying the relationship between fingertip temperature changes and arterial function during vascular reactivity test, we established a new non-invasive method for detecting vascular function, in order to provide an assistance for early diagnosis and prevention of cardiovascular diseases. We customized three modules respectively for blood occlusion, measurement of finger temperature and blood oxygen acquisition, and then we established the hardware of data acquisition system. And the software was programmed with Labview. Healthy subjects [group A, n = 24, (44.6 ± 9.0) years] and subjects with cardiovascular diseases [group B, n = 33, (57.2 ± 9.9) years)] were chosen for the study. Subject's finger temperature, blood oxygen and occlusion pressure of block side during and after unilateral arm brachial artery occlusion were recorded, as well as some other regular physiological indexes. By time-domain analysis, we extracted 12 parameters from fingertip temperature signal, including the initial temperature (Ti), temperature rebound (TR), the time of the temperature recovering to initial status (RIt) and other parameters from the finger temperature signal. We in the experiment also measured other regular physiological body mass index (BMI), systolic blood pressure (SBP), diastiolic blood pressure (DBP) and so on. Results showed that 8 parameters difference between the two group of data were significant. based on the statistical results. A discriminant function of vascular function status was established afterwards. We found in the study that the changes of finger temperature during unilateral arms brachial artery occlusion and open were closely related to vascular function. We hope that the method presented in this article could lay a foundation of early detection of vascular function. PMID:27382755

  10. Beyond the brain-Peripheral kisspeptin signaling is essential for promoting endometrial gland development and function

    PubMed Central

    León, Silvia; Fernadois, Daniela; Sull, Alexandra; Sull, Judith; Calder, Michele; Hayashi, Kanako; Bhattacharya, Moshmi; Power, Stephen; Vilos, George A.; Vilos, Angelos G.; Tena-Sempere, Manuel; Babwah, Andy V.

    2016-01-01

    Uterine growth and endometrial gland formation (adenogenesis) and function, are essential for fertility and are controlled by estrogens and other regulators, whose nature and physiological relevance are yet to be elucidated. Kisspeptin, which signals via Kiss1r, is essential for fertility, primarily through its central control of the hypothalamic-pituitary-ovarian axis, but also likely through peripheral actions. Using genetically modified mice, we addressed the contributions of central and peripheral kisspeptin signaling in regulating uterine growth and adenogenesis. Global ablation of Kiss1 or Kiss1r dramatically suppressed uterine growth and almost fully prevented adenogenesis. However, while uterine growth was fully rescued by E2 treatment of Kiss1−/− mice and by genetic restoration of kisspeptin signaling in GnRH neurons in Kiss1r−/− mice, functional adenogenesis was only marginally restored. Thus, while uterine growth is largely dependent on ovarian E2-output via central kisspeptin signaling, peripheral kisspeptin signaling is indispensable for endometrial adenogenesis and function, essential aspects of reproductive competence. PMID:27364226

  11. Reduced Numbers and Impaired Function of Regulatory T Cells in Peripheral Blood of Ischemic Stroke Patients.

    PubMed

    Ruhnau, Johanna; Schulze, Juliane; von Sarnowski, Bettina; Heinrich, Marie; Langner, Sönke; Pötschke, Christian; Wilden, Anika; Kessler, Christof; Bröker, Barbara M; Vogelgesang, Antje; Dressel, Alexander

    2016-01-01

    Background and Purpose. Regulatory T cells (Tregs) have been suggested to modulate stroke-induced immune responses. However, analyses of Tregs in patients and in experimental stroke have yielded contradictory findings. We performed the current study to assess the regulation and function of Tregs in peripheral blood of stroke patients. Age dependent expression of CD39 on Tregs was quantified in mice and men. Methods. Total FoxP3(+) Tregs and CD39(+)FoxP3(+) Tregs were quantified by flow cytometry in controls and stroke patients on admission and on days 1, 3, 5, and 7 thereafter. Treg function was assessed by quantifying the inhibition of activation-induced expression of CD69 and CD154 on T effector cells (Teffs). Results. Total Tregs accounted for 5.0% of CD4(+) T cells in controls and <2.8% in stroke patients on admission. They remained below control values until day 7. CD39(+) Tregs were most strongly reduced in stroke patients. On day 3 the Treg-mediated inhibition of CD154 upregulation on CD4(+) Teff was impaired in stroke patients. CD39 expression on Treg increased with age in peripheral blood of mice and men. Conclusion. We demonstrate a loss of active FoxP3(+)CD39(+) Tregs from stroke patient's peripheral blood. The suppressive Treg function of remaining Tregs is impaired after stroke. PMID:27073295

  12. Beyond the brain-Peripheral kisspeptin signaling is essential for promoting endometrial gland development and function.

    PubMed

    León, Silvia; Fernadois, Daniela; Sull, Alexandra; Sull, Judith; Calder, Michele; Hayashi, Kanako; Bhattacharya, Moshmi; Power, Stephen; Vilos, George A; Vilos, Angelos G; Tena-Sempere, Manuel; Babwah, Andy V

    2016-01-01

    Uterine growth and endometrial gland formation (adenogenesis) and function, are essential for fertility and are controlled by estrogens and other regulators, whose nature and physiological relevance are yet to be elucidated. Kisspeptin, which signals via Kiss1r, is essential for fertility, primarily through its central control of the hypothalamic-pituitary-ovarian axis, but also likely through peripheral actions. Using genetically modified mice, we addressed the contributions of central and peripheral kisspeptin signaling in regulating uterine growth and adenogenesis. Global ablation of Kiss1 or Kiss1r dramatically suppressed uterine growth and almost fully prevented adenogenesis. However, while uterine growth was fully rescued by E2 treatment of Kiss1(-/-) mice and by genetic restoration of kisspeptin signaling in GnRH neurons in Kiss1r(-/-) mice, functional adenogenesis was only marginally restored. Thus, while uterine growth is largely dependent on ovarian E2-output via central kisspeptin signaling, peripheral kisspeptin signaling is indispensable for endometrial adenogenesis and function, essential aspects of reproductive competence. PMID:27364226

  13. Hydrogen-rich saline promotes motor functional recovery following peripheral nerve autografting in rats

    PubMed Central

    ZHANG, YONG-GUANG; SHENG, QING-SONG; WANG, ZHI-JUN; LV, LI; ZHAO, WEI; CHEN, JIAN-MEI; XU, HAO

    2015-01-01

    Despite the application of nerve grafts and considerable microsurgical innovations, the functional recovery across a long peripheral nerve gap is generally partial and unsatisfactory. Thus, additional strategies are required to improve nerve regeneration across long nerve gaps. Hydrogen possesses antioxidant and anti-apoptotic properties, which could be neuroprotective in the treatment of peripheral nerve injury; however, such a possibility has not been experimentally tested in vivo. The aim of the present study was to investigate the effectiveness of hydrogen-rich saline in promoting nerve regeneration after 10-mm sciatic nerve autografting in rats. The rats were randomly divided into two groups and intraperitoneally administered a daily regimen of 5 ml/kg hydrogen-rich or normal saline. Axonal regeneration and functional recovery were assessed through a combination of behavioral analyses, electrophysiological evaluations, Fluoro-Gold™ retrograde tracings and histomorphological observations. The data showed that rats receiving hydrogen-rich saline achieved better axonal regeneration and functional recovery than those receiving normal saline. These findings indicated that hydrogen-rich saline promotes nerve regeneration across long gaps, suggesting that hydrogen-rich saline could be used as a neuroprotective agent for peripheral nerve injury therapy. PMID:26622383

  14. Reduced Numbers and Impaired Function of Regulatory T Cells in Peripheral Blood of Ischemic Stroke Patients

    PubMed Central

    Ruhnau, Johanna; Schulze, Juliane; von Sarnowski, Bettina; Heinrich, Marie; Langner, Sönke; Wilden, Anika; Kessler, Christof; Bröker, Barbara M.

    2016-01-01

    Background and Purpose. Regulatory T cells (Tregs) have been suggested to modulate stroke-induced immune responses. However, analyses of Tregs in patients and in experimental stroke have yielded contradictory findings. We performed the current study to assess the regulation and function of Tregs in peripheral blood of stroke patients. Age dependent expression of CD39 on Tregs was quantified in mice and men. Methods. Total FoxP3+ Tregs and CD39+FoxP3+ Tregs were quantified by flow cytometry in controls and stroke patients on admission and on days 1, 3, 5, and 7 thereafter. Treg function was assessed by quantifying the inhibition of activation-induced expression of CD69 and CD154 on T effector cells (Teffs). Results. Total Tregs accounted for 5.0% of CD4+ T cells in controls and <2.8% in stroke patients on admission. They remained below control values until day 7. CD39+ Tregs were most strongly reduced in stroke patients. On day 3 the Treg-mediated inhibition of CD154 upregulation on CD4+ Teff was impaired in stroke patients. CD39 expression on Treg increased with age in peripheral blood of mice and men. Conclusion. We demonstrate a loss of active FoxP3+CD39+ Tregs from stroke patient's peripheral blood. The suppressive Treg function of remaining Tregs is impaired after stroke. PMID:27073295

  15. High peripheral blood th17 percent associated with poor lung function in cystic fibrosis.

    PubMed

    Mulcahy, Emily M; Hudson, Jo B; Beggs, Sean A; Reid, David W; Roddam, Louise F; Cooley, Margaret A

    2015-01-01

    People with cystic fibrosis (CF) have been reported to make lung T cell responses that are biased towards T helper (Th) 2 or Th17. We hypothesized that CF-related T cell regulatory defects could be detected by analyzing CD4+ lymphocyte subsets in peripheral blood. Peripheral blood mononuclear cells from 42 CF patients (6 months-53 years old) and 78 healthy controls (2-61 years old) were analyzed for Th1 (IFN-γ+), Th2 (IL-4+), Th17 (IL-17+), Treg (FOXP3+), IL-10+ and TGF-β+ CD4+ cells. We observed higher proportions of Treg, IL-10+ and TGF-β+ CD4+ cells in CF adults (≥ 18 years old), but not children/adolescents, compared with controls. Within the CF group, high TGF-β+% was associated with chronic Pseudomonas aeruginosa lung infection (p < 0.006). We observed no significant differences between control and CF groups in the proportions of Th1, Th2 or Th17 cells, and no association within the CF group of any subset with sex, CFTR genotype, or clinical exacerbation. However, high Th17% was strongly associated with poor lung function (FEV1 % predicted) (p = 0.0008), and this association was strongest when both lung function testing and blood sampling were performed within one week. Our results are consistent with reports of CF as a Th17 disease and suggest that peripheral blood Th17 levels may be a surrogate marker of lung function in CF. PMID:25803862

  16. A novel approach to the assessment of vascular endothelial function

    NASA Astrophysics Data System (ADS)

    Sathasivam, S.; Phababpha, S.; Sengmeuan, P.; Detchaporn, P.; Siddiqui, Z.; Kukongviriyapan, U.; Greenwald, S.

    2011-08-01

    Impaired endothelial function (EF) is associated with atherogenesis, and its quantitative assessment has prognostic value. Currently, methods based on assessing flow-mediated dilation (FMD) are technically difficult and expensive. We tested a novel way of assessing EF by measuring the time difference between pulses arriving at the middle fingers of each hand (f-fΔT), whilst FMD is induced in one arm. We compared f-fΔT with standard methods in healthy and diseased subjects. Our findings suggest that the proposed simple and inexpensive technique gives comparable results and has the potential to qualitatively assess EF in the clinical setting, although further work is required.

  17. LOWER EXTREMITY MANIFESTATIONS OF PERIPHERAL ARTERY DISEASE: THE PATHOPHYSIOLOGIC AND FUNCTIONAL IMPLICATIONS OF LEG ISCHEMIA

    PubMed Central

    McDermott, Mary McGrae

    2015-01-01

    Lower extremity peripheral artery disease (PAD) is frequently under-diagnosed, in part because of the wide variety of leg symptoms manifested by patients with PAD and in part because of the high prevalence of asymptomatic PAD. In primary care medical practices, 30% to 60% of PAD patients report no exertional leg symptoms and approximately 45–50% report exertional leg symptoms that are not consistent with classic intermittent claudication. The prevalence and extent of functional impairment and functional decline in PAD may also be underappreciated. Functional impairment and functional decline is common in PAD, even among those who are asymptomatic. Lower extremity ischemia is also associated with pathophysiologic changes in calf skeletal muscle including smaller calf muscle area, increased calf muscle fat content, impaired leg strength, and impaired metabolic function. People with severe PAD have poorer peroneal nerve conduction velocity compared to people with mild PAD or no PAD. The degree of ischemia-related pathophysiologic changes in lower extremity muscles and peripheral nerves of people with PAD are associated with the degree of functional impairment. New interventions are needed to improve functional performance and prevent mobility loss in the large number of PAD patients, including in those who are asymptomatic or who have exertional leg symptoms other than claudication. PMID:25908727

  18. Enhanced biocompatibility of CD47-functionalized vascular stents.

    PubMed

    Slee, Joshua B; Alferiev, Ivan S; Nagaswami, Chandrasekaran; Weisel, John W; Levy, Robert J; Fishbein, Ilia; Stachelek, Stanley J

    2016-05-01

    The effectiveness of endovascular stents is hindered by in-stent restenosis (ISR), a secondary re-obstruction of treated arteries due to unresolved inflammation and activation of smooth muscle cells in the arterial wall. We previously demonstrated that immobilized CD47, a ubiquitously expressed transmembrane protein with an established role in immune evasion, can confer biocompatibility when appended to polymeric surfaces. In present studies, we test the hypothesis that CD47 immobilized onto metallic surfaces of stents can effectively inhibit the inflammatory response thus mitigating ISR. Recombinant CD47 (recCD47) or a peptide sequence corresponding to the Ig domain of CD47 (pepCD47), were attached to the surfaces of both 316L-grade stainless steel foils and stents using bisphosphonate coordination chemistry and thiol-based conjugation reactions to assess the anti-inflammatory properties of CD47-functionalized surfaces. Initial in vitro and ex vivo analysis demonstrated that both recCD47 and pepCD47 significantly reduced inflammatory cell attachment to steel surfaces without impeding on endothelial cell retention and expansion. Using a rat carotid stent model, we showed that pepCD47-functionalized stents prevented fibrin and platelet thrombus deposition, inhibited inflammatory cell attachment, and reduced restenosis by 30%. It is concluded that CD47-modified stent surfaces mitigate platelet and inflammatory cell attachment, thereby disrupting ISR pathophysiology. PMID:26914699

  19. Left Ventricular Diastolic Dysfunction in Ischemic Stroke: Functional and Vascular Outcomes

    PubMed Central

    Park, Hong-Kyun; Kim, Beom Joon; Yoon, Chang-Hwan; Yang, Mi Hwa; Han, Moon-Ku; Bae, Hee-Joon

    2016-01-01

    Background and Purpose Left ventricular (LV) diastolic dysfunction, developed in relation to myocardial dysfunction and remodeling, is documented in 15%-25% of the population. However, its role in functional recovery and recurrent vascular events after acute ischemic stroke has not been thoroughly investigated. Methods In this retrospective observational study, we identified 2,827 ischemic stroke cases with adequate echocardiographic evaluations to assess LV diastolic dysfunction within 1 month after the index stroke. The peak transmitral filling velocity/mean mitral annular velocity during early diastole (E/e’) was used to estimate LV diastolic dysfunction. We divided patients into 3 groups according to E/e’ as follows: <8, 8-15, and ≥15. Recurrent vascular events and functional recovery were prospectively collected at 3 months and 1 year. Results Among included patients, E/e’ was 10.6±6.4: E/e’ <8 in 993 (35%), 8-15 in 1,444 (51%), and ≥15 in 378 (13%) cases. Functional dependency or death (modified Rankin Scale score ≥2) and composite vascular events were documented in 1,298 (46%) and 187 (7%) patients, respectively, at 3 months. In multivariable analyses, ischemic stroke cases with E/e’ ≥15 had increased odds of functional dependence or death at 3 months (adjusted OR [95% CI]: 1.73 [1.27-2.35]) or 1 year (1.47 [1.06-2.06]) and vascular events within 1 year (1.65 [1.08-2.51]). Subgroups with normal ejection fraction or sinus rhythm exhibited a similar overall pattern and direction. Conclusions LV diastolic dysfunction was associated with poor functional outcomes and composite vascular events up to 1 year. PMID:27283279

  20. Preeclampsia and Vascular Function: A Window to Future Cardiovascular Disease Risk.

    PubMed

    Enkhmaa, Davaasambuu; Wall, Danielle; Mehta, Puja K; Stuart, Jennifer J; Rich-Edwards, Janet Wilson; Merz, C Noel Bairey; Shufelt, Chrisandra

    2016-03-01

    Preeclampsia affects ∼3%-7% of all pregnancies and is the third leading cause of maternal mortality globally. Growing evidence indicates that preeclampsia results from vascular dysfunction, which also increases the risk for future cardiovascular events. Until recently, preeclampsia was considered a disorder limited to pregnancy, which fully resolved with the delivery of the placenta; however, it is now clear that women with a history of preeclampsia have approximately double the risk of future cardiovascular events compared to women with normotensive pregnancies. The aims of this review were to describe the hemodynamic and vascular changes that occur in normal and preeclamptic pregnancies, to review noninvasive methods to test vascular function, and to discuss the associated increased cardiovascular disease risk related to preeclampsia. PMID:26779584

  1. Alterations in vascular function in primary aldosteronism: a cardiovascular magnetic resonance imaging study.

    PubMed

    Mark, P B; Boyle, S; Zimmerli, L U; McQuarrie, E P; Delles, C; Freel, E M

    2014-02-01

    Excess aldosterone is associated with increased cardiovascular risk. Aldosterone has a permissive effect on vascular fibrosis. Cardiovascular magnetic resonance imaging (CMR) allows study of vascular function by measuring aortic distensibility. We compared aortic distensibility in primary aldosteronism (PA), essential hypertension (EH) and normal controls and explored the relationship between aortic distensibility and pulse wave velocity (PWV). We studied PA (n=14) and EH (n=33) subjects and age-matched healthy controls (n=17) with CMR, including measurement of aortic distensibility, and measured PWV using applanation tonometry. At recruitment, PA and EH patients had similar blood pressure and left ventricular mass. Subjects with PA had significantly lower aortic distensibility and higher PWV compared with EH and healthy controls. These changes were independent of other factors associated with reduced aortic distensibility, including ageing. There was a significant relationship between increasing aortic stiffness and age in keeping with physical and vascular ageing. As expected, aortic distensibility and PWV were closely correlated. These results demonstrate that PA patients display increased arterial stiffness compared with EH, independent of vascular ageing. The implication is that aldosterone invokes functional impairment of arterial function. The long-term implications of arterial stiffening in aldosterone excess require further study. PMID:23884211

  2. Clinical Correlates of Hachinski Ischemic Score and Vascular Factors in Cognitive Function of Elderly

    PubMed Central

    Kim, Youn Ho

    2014-01-01

    The aim of this study is to investigate the relationship between Hachinski ischemic score (HIS) and vascular factors as well as between HIS and the cognitive function in elderly community. Demographic characteristics, such as sex, age, education, history of drinking and smoking, family history of dementia and stroke, diabetes mellitus, hypertension, hyperlipidemia, cardiovascular disease, stroke, and dementia, were surveyed. Neurological examination was administered to every subject and HIS was checked by a neurologist. From a total of 392 participants aged 65 and over in a rural community, 348 completed the survey and were finally enrolled. Among the vascular factors, history of hypertension (P = 0.008), history of stroke (P < 0.001), family history of dementia (P = 0.01), and history of cardiac diseases (P = 0.012) showed a significant relationship with HIS. In the cognitive function tests, both Korean version of the Mini-Mental State Examination and the Clinical Dementia Rating (Global and Sum of Boxes) had a significant relationship with HIS. Our study suggested HIS may have an association with some vascular factors and cognitive scales in community dwelling elderly. In this study, the HIS seemed to contribute to the evaluation of the quantity of vascular factors and to the prediction of status of cognitive function. PMID:25247189

  3. Advances of Peripheral Nerve Repair Techniques to Improve Hand Function: A Systematic Review of Literature

    PubMed Central

    P, Mafi; S, Hindocha; M, Dhital; M, Saleh

    2012-01-01

    Concepts of neuronal damage and repair date back to ancient times. The research in this topic has been growing ever since and numerous nerve repair techniques have evolved throughout the years. Due to our greater understanding of nerve injuries and repair we now distinguish between central and peripheral nervous system. In this review, we have chosen to concentrate on peripheral nerve injuries and in particular those involving the hand. There are no reviews bringing together and summarizing the latest research evidence concerning the most up-to-date techniques used to improve hand function. Therefore, by identifying and evaluating all the published literature in this field, we have summarized all the available information about the advances in peripheral nerve techniques used to improve hand function. The most important ones are the use of resorbable poly[(R)-3-hydroxybutyrate] (PHB), epineural end-to-end suturing, graft repair, nerve transfer, side to side neurorrhaphy and end to side neurorrhaphy between median, radial and ulnar nerves, nerve transplant, nerve repair, external neurolysis and epineural sutures, adjacent neurotization without nerve suturing, Agee endoscopic operation, tourniquet induced anesthesia, toe transfer and meticulous intrinsic repair, free auto nerve grafting, use of distal based neurocutaneous flaps and tubulization. At the same time we found that the patient’s age, tension of repair, time of repair, level of injury and scar formation following surgery affect the prognosis. Despite the thorough findings of this systematic review we suggest that further research in this field is needed. PMID:22431951

  4. VEGF-B selectively regenerates injured peripheral neurons and restores sensory and trophic functions

    PubMed Central

    Guaiquil, Victor H.; Pan, Zan; Karagianni, Natalia; Fukuoka, Shima; Alegre, Gemstonn; Rosenblatt, Mark I.

    2014-01-01

    VEGF-B primarily provides neuroprotection and improves survival in CNS-derived neurons. However, its actions on the peripheral nervous system have been less characterized. We examined whether VEGF-B mediates peripheral nerve repair. We found that VEGF-B induced extensive neurite growth and branching in trigeminal ganglia neurons in a manner that required selective activation of transmembrane receptors and was distinct from VEGF-A–induced neuronal growth. VEGF-B–induced neurite elongation required PI3K and Notch signaling. In vivo, VEGF-B is required for normal nerve regeneration: mice lacking VEGF-B showed impaired nerve repair with concomitant impaired trophic function. VEGF-B treatment increased nerve regeneration, sensation recovery, and trophic functions of injured corneal peripheral nerves in VEGF-B–deficient and wild-type animals, without affecting uninjured nerves. These selective effects of VEGF-B on injured nerves and its lack of angiogenic activity makes VEGF-B a suitable therapeutic target to treat nerve injury. PMID:25404333

  5. The effect of ozone inhalation on metabolic functioning of vascular endothelium and on ventilatory function

    SciTech Connect

    Gross, K.B.; White, H.J.; Sargent, N.E. )

    1991-06-15

    The primary purpose of this research was to determine the effect of ozone inhalation on pulmonary vascular endothelium. Male Fischer-344 rats were exposed to 0.5 or 0.7 ppm ozone, 20 hr/day for 7 days. Lungs were excised and perfused with Krebs medium containing (14C)serotonin or (14C)hippurylhistidylleucine (HHL). When compared to controls, the animals exposed to the lower ozone concentration showed no statistically significant changes in serotonin removal. In contrast, the higher ozone concentration resulted in a 32% decrease (p less than 0.0001) in serotonin removal, but had no effect on HHL. Rats similarly exposed to 0.7 ppm ozone but allowed to recover for 14 days in clean air showed no decrease in serotonin removal compared to their controls. Animals exposed sequentially to 0.5 ppm ozone for 7 days and then to 0.7 ppm for 7 days showed no alteration in serotonin metabolism, suggesting the development of tolerance initiated by the lower dose. After 7 days exposure to 0.7 ppm ozone, lung ventilatory function measurements revealed small though significant decreases in several parameters. Electron microscopic evaluation of lung capillary endothelium from animals exposed to the 0.7 ppm ozone showed no changes. Positive control animals exposed to greater than 95% oxygen, 20 hr/day for 2 days showed a 23% decrease in serotonin removal (p less than 0.03) and a 12% decrease in HHL removal (p less than 0.017). These studies indicate that inhalation of ozone can induce functional alterations in the lung endothelium, and that this effect occurs at a dosage of ozone that produces minimal ventilatory changes and no observable endothelial ultrastructural changes.

  6. Impaired renal function impacts negatively on vascular stiffness in patients with coronary artery disease

    PubMed Central

    2013-01-01

    Background Chronic kidney disease (CKD) and coronary artery disease (CAD) are independently associated with increased vascular stiffness. We examined whether renal function contributes to vascular stiffness independently of CAD status. Methods We studied 160 patients with CAD and 169 subjects without CAD. The 4-variable MDRD formula was used to estimate glomerular filtration rate (eGFR); impaired renal function was defined as eGFR <60 mL/min. Carotid-femoral pulse wave velocity (PWV) was measured with the SphygmoCor® device. Circulating biomarkers were assessed in plasma using xMAP® multiplexing technology. Results Patients with CAD and impaired renal function had greater PWV compared to those with CAD and normal renal function (10.2 [9.1;11.2] vs 7.3 [6.9;7.7] m/s; P < 0.001). In all patients, PWV was a function of eGFR (β = −0.293; P < 0.001) even after adjustment for age, sex, systolic blood pressure, body mass index and presence or absence of CAD. Patients with CAD and impaired renal function had higher levels of adhesion and inflammatory molecules including E-selectin and osteopontin (all P < 0.05) compared to those with CAD alone, but had similar levels of markers of oxidative stress. Conclusions Renal function is a determinant of vascular stiffness even in patients with severe atherosclerotic disease. This was paralleled by differences in markers of cell adhesion and inflammation. Increased vascular stiffness may therefore be linked to inflammatory remodeling of the vasculature in people with impaired renal function, irrespective of concomitant atherosclerotic disease. PMID:23937620

  7. Functional genomics indicate that schizophrenia may be an adult vascular-ischemic disorder

    PubMed Central

    Moises, H W; Wollschläger, D; Binder, H

    2015-01-01

    In search for the elusive schizophrenia pathway, candidate genes for the disorder from a discovery sample were localized within the energy-delivering and ischemia protection pathway. To test the adult vascular-ischemic (AVIH) and the competing neurodevelopmental hypothesis (NDH), functional genomic analyses of practically all available schizophrenia-associated genes from candidate gene, genome-wide association and postmortem expression studies were performed. Our results indicate a significant overrepresentation of genes involved in vascular function (P<0.001), vasoregulation (that is, perivascular (P<0.001) and shear stress (P<0.01), cerebral ischemia (P<0.001), neurodevelopment (P<0.001) and postischemic repair (P<0.001) among schizophrenia-associated genes from genetic association studies. These findings support both the NDH and the AVIH. The genes from postmortem studies showed an upregulation of vascular-ischemic genes (P=0.020) combined with downregulated synaptic (P=0.005) genes, and ND/repair (P=0.003) genes. Evidence for the AVIH and the NDH is critically discussed. We conclude that schizophrenia is probably a mild adult vascular-ischemic and postischemic repair disorder. Adult postischemic repair involves ND genes for adult neurogenesis, synaptic plasticity, glutamate and increased long-term potentiation of excitatory neurotransmission (i-LTP). Schizophrenia might be caused by the cerebral analog of microvascular angina. PMID:26261884

  8. Pathophysiology and burden of infection in patients with diabetes mellitus and peripheral vascular disease: focus on skin and soft-tissue infections.

    PubMed

    Dryden, M; Baguneid, M; Eckmann, C; Corman, S; Stephens, J; Solem, C; Li, J; Charbonneau, C; Baillon-Plot, N; Haider, S

    2015-09-01

    Diabetes mellitus affects 284 million adults worldwide and is increasing in prevalence. Accelerated atherosclerosis in patients with diabetes mellitus contributes an increased risk of developing cardiovascular diseases including peripheral vascular disease (PVD). Immune dysfunction, diabetic neuropathy and poor circulation in patients with diabetes mellitus, especially those with PVD, place these patients at high risk for many types of typical and atypical infections. Complicated skin and soft-tissue infections (cSSTIs) are of particular concern because skin breakdown in patients with advanced diabetes mellitus and PVD provides a portal of entry for bacteria. Patients with diabetes mellitus are more likely to be hospitalized with cSSTIs and to experience related complications than patients without diabetes mellitus. Patients with PVD requiring lower extremity bypass are also at high risk of surgical site and graft infections. Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent causative pathogen in cSSTIs, and may be a significant contributor to surgical site infections, especially in patients who are colonized with MRSA on hospital admission. Patients with cSSTIs and diabetes mellitus or PVD experience lower clinical success rates than patients without these comorbidities, and may also have a longer length of hospital stay and higher risk of adverse drug events. Clinicians should be vigilant in recognizing the potential for infection with multi-drug-resistant organisms, especially MRSA, in these populations and initiating therapy with appropriate antibiotics. PMID:26198368

  9. Nonoccupational environmental exposure to manganese is linked to deficits in peripheral and central olfactory function.

    PubMed

    Guarneros, Marco; Ortiz-Romo, Nahum; Alcaraz-Zubeldia, Mireya; Drucker-Colín, René; Hudson, Robyn

    2013-11-01

    Manganese is of growing concern as a toxic air pollutant. It is readily transported from the olfactory epithelium to the olfactory bulb, and unlike other metals, it is transported transynaptically to structures deep within the brain. However, little is known regarding the possible effect of nonoccupational exposure to manganese on olfactory function. Using the Sniffin' Sticks test battery, we compared the olfactory performance of subjects from a manganese mining district living <1 km from a manganese processing plant, with nonexposed subjects living 50 km from the closest source of exposure (N = 30/group). Groups were matched for age, sex, and schooling, and none had ever worked in mining-related activities. Concentrations of manganese in hair were measured as a biomarker of exposure; exposed subjects had significantly higher concentrations than nonexposed subjects. They were also significantly outperformed by the nonexposed subjects on all olfactory measures (threshold, discrimination, and identification), indicating adverse effects of manganese exposure on a range of olfactory functions, including those involving higher order cognitive processes. This contrasts with previous findings showing adverse peripheral but not central effects on olfactory function of big city air pollution, which mostly consists of toxicants known to affect the olfactory epithelium but with lower transynaptic transport capacity compared with manganese. We conclude that nonoccupational exposure to airborne manganese is associated with decrements in both peripheral and central olfactory function. PMID:24097266

  10. Functional selectivity of kappa opioid receptor agonists in peripheral sensory neurons.

    PubMed

    Jamshidi, Raehannah J; Jacobs, Blaine A; Sullivan, Laura C; Chavera, Teresa A; Saylor, Rachel M; Prisinzano, Thomas E; Clarke, William P; Berg, Kelly A

    2015-11-01

    Activation of kappa opioid receptors (KORs) expressed by peripheral sensory neurons that respond to noxious stimuli (nociceptors) can reduce neurotransmission of pain stimuli from the periphery to the central nervous system. We have previously shown that the antinociception dose-response curve for peripherally restricted doses of the KOR agonist (-)-(trans)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]benzeneacetamide (U50488) has an inverted U shape. Here, we found that the downward phase of the U50488 dose-response curve was blocked by an inhibitor of extracellular signal-regulated kinase (ERK) activation U0126. Local administration of the selective KOR agonist salvinorin A (Sal-A), also resulted in an inverted U-shaped curve; however, the downward phase was insensitive to U0126. By contrast, inhibition of c-Jun N-terminal kinase (JNK) partially blocked the downward phase of the dose-response curve to Sal-A, suggesting a role for JNK. In cultures of peripheral sensory neurons, U50488 and Sal-A inhibited adenylyl cyclase activity with similar efficacies; however, their ability to activate ERK and JNK differed. Whereas U50488 activated ERK but not JNK, Sal-A activated JNK but not ERK. Moreover, although both U50488 and Sal-A produced homologous desensitization, desensitization to U50488 was blocked by inhibition of ERK activation, whereas desensitization to Sal-A was blocked by inhibition of JNK. Substitution of an ethoxymethyl ether for the C2 position acetyl group of Sal-A reduced stimulation of JNK, prevented desensitization by ethoxymethyl ether for the C2 position acetyl group of Sal-A, and resulted in a monotonic antinociception dose-response curve. Collectively, these data demonstrate the functional selectivity of KOR ligands for signaling in peripheral sensory neurons, which results in differential effects on behavioral responses in vivo. PMID:26297384

  11. Mobility-Related Consequences of Reduced Lower-Extremity Peripheral Nerve Function with Age: A Systematic Review

    PubMed Central

    Ward, Rachel E.; Caserotti, Paolo; Cauley, Jane A.; Boudreau, Robert M.; Goodpaster, Bret H.; Vinik, Aaron I.; Newman, Anne B.; Strotmeyer, Elsa S.

    2016-01-01

    The objective of this study is to systematically review the relationship between lower-extremity peripheral nerve function and mobility in older adults. The National Library of Medicine (PubMed) was searched on March 23, 2015 with no limits on publication dates. One reviewer selected original research studies of older adults (≥65 years) that assessed the relationship between lower-extremity peripheral nerve function and mobility-related outcomes. Participants, study design and methods of assessing peripheral nerve impairment were evaluated and results were reported and synthesized. Eight articles were identified, including 6 cross-sectional and 2 longitudinal studies. These articles investigated 6 elderly cohorts (4 from the U.S. and 2 from Italy): 3 community-dwelling (including 1 with only disabled women and 1 without mobility limitations at baseline), 1 with both community-dwelling and institutionalized residents, 1 from a range of residential locations, and 1 of patients with peripheral arterial disease. Mean ages ranged from 71-82 years. Nerve function was assessed by vibration threshold (n=2); sensory measures and clinical signs and symptoms of neuropathy (n=2); motor nerve conduction (n=1); and a combination of both sensory measures and motor nerve conduction (n=3). Each study found that worse peripheral nerve function was related to poor mobility, although relationships varied based on the nerve function measure and mobility domain assessed. Six studies found that the association between nerve function and mobility persisted despite adjustment for diabetes. Evidence suggests that peripheral nerve function impairment at various levels of severity is related to poor mobility independent of diabetes. Relationships varied depending on peripheral nerve measure, which may be particularly important when investigating specific biological mechanisms. Future research needs to identify risk factors for peripheral nerve decline beyond diabetes, especially those

  12. Mobility-Related Consequences of Reduced Lower-Extremity Peripheral Nerve Function with Age: A Systematic Review.

    PubMed

    Ward, Rachel E; Caserotti, Paolo; Cauley, Jane A; Boudreau, Robert M; Goodpaster, Bret H; Vinik, Aaron I; Newman, Anne B; Strotmeyer, Elsa S

    2016-08-01

    The objective of this study is to systematically review the relationship between lower-extremity peripheral nerve function and mobility in older adults. The National Library of Medicine (PubMed) was searched on March 23, 2015 with no limits on publication dates. One reviewer selected original research studies of older adults (≥65 years) that assessed the relationship between lower-extremity peripheral nerve function and mobility-related outcomes. Participants, study design and methods of assessing peripheral nerve impairment were evaluated and results were reported and synthesized. Eight articles were identified, including 6 cross-sectional and 2 longitudinal studies. These articles investigated 6 elderly cohorts (4 from the U.S. and 2 from Italy): 3 community-dwelling (including 1 with only disabled women and 1 without mobility limitations at baseline), 1 with both community-dwelling and institutionalized residents, 1 from a range of residential locations, and 1 of patients with peripheral arterial disease. Mean ages ranged from 71-82 years. Nerve function was assessed by vibration threshold (n=2); sensory measures and clinical signs and symptoms of neuropathy (n=2); motor nerve conduction (n=1); and a combination of both sensory measures and motor nerve conduction (n=3). Each study found that worse peripheral nerve function was related to poor mobility, although relationships varied based on the nerve function measure and mobility domain assessed. Six studies found that the association between nerve function and mobility persisted despite adjustment for diabetes. Evidence suggests that peripheral nerve function impairment at various levels of severity is related to poor mobility independent of diabetes. Relationships varied depending on peripheral nerve measure, which may be particularly important when investigating specific biological mechanisms. Future research needs to identify risk factors for peripheral nerve decline beyond diabetes, especially those

  13. [Vascular vertigo syndromes].

    PubMed

    Dieterich, M

    2002-12-01

    Ischemia,hemorrhages, and other vascular disorders can result in various central or peripheral vestibular syndromes with vertigo, oculomotor/balance disturbances, and nausea. The vascular vertigo syndromes listed in Table 1 can however be brought about by other causes such as demyelitizing focuses in multiple sclerosis or space-occupying lesions, so that not only localization of the damaged structure but also the various etiologies are decisive for the choice of therapy. Occasionally, combined functional disturbances of the peripheral and central vestibular system appear, such as an infarction of the inferior anterior cerebellar artery, which supplies the labyrinth and parts of the brainstem and cerebellum. In rare cases, a central lesion can have the same signs as a peripheral-vertibular disturbance: a lacunar infarct at the root entry zone of the eighth nerve can mimic a unilateral partial loss of labyrinth function as it occurs in vestibular neuritis, thus named "pseudoneuritis". Differential diagnosis between vestibular migraine, vestibular paroxysmia, transient ischemic brainstem attacks, and Meniere's disease is sometimes so difficult that only trial therapies such as prophylaxis with beta blockers, carbamazepine, thrombocyte aggregation inhibitors, antiplatelet drugs, or betahistin can clarify the issue. PMID:12486562

  14. Interleukin-17 as a novel predictor of vascular function in rheumatoid arthritis

    PubMed Central

    Marder, Wendy; Khalatbari, Shokoufeh; Myles, James D.; Hench, Rita; Yalavarthi, Srilakshmi; Lustig, Susan; Brook, Robert; Kaplan, Mariana J.

    2011-01-01

    Objectives Rheumatoid arthritis (RA) is associated with enhanced cardiovascular (CV) risk and subclinical vascular disease. The proinflammatory milieu has been linked to premature atherosclerosis and endothelial dysfunction in RA. While IL-17 is considered pathogenic in RA, its role in determining vascular dysfunction in this disease has not been systematically assessed. We analyzed candidate variables that could determine endothelial function in various vascular territories in a cohort of RA patients on biologic therapy, with minimal traditional CV risk factors and low disease activity score. Methods RA patients (n=51) on stable biologic therapy underwent measurement of conduit artery endothelial function by brachial artery flow-mediated dilatation (FMD); arterial compliance by pulse wave velocity (PWV) assessment; and endothelium-dependent microvascular testing with Endo-PAT2000 device to assess reactive hyperemia index (RHI). IL-17 was quantified by ELISA and disease activity was assessed by DAS-28. Results IL-17 and high sensitivity CRP were the main determinants of lower RHI in univariate (p=0.004, <0.001) and multivariate (p=0.004, <0.0001) analysis, respectively. Traditional and non-traditional CV risk variables determined PWV, with a significant positive association with IL-17 in univariate and multivariate analysis (p=0.02, 0.01, respectively). In contrast, conduit endothelial function was mainly determined by rheumatoid factor titers (p=0.003). Anti-CCP titers and disease activity did not determine vascular function. Conclusion In RA patients treated with biologics, IL-17 is a main predictor of microvascular function and arterial compliance. This study suggests IL-17 may play a significant role in development of endothelial dysfunction and CVD in RA. PMID:21727237

  15. Peripheral artery bypass - leg

    MedlinePlus

    ... P. Peripheral arterial diseases. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's ... noncoronary obstructive vascular disease.In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's ...

  16. ECM-mimetic heparin glycosamioglycan-functionalized surface favors constructing functional vascular smooth muscle tissue in vitro.

    PubMed

    Zhang, Jimin; Wang, Jianing; Wei, Yongzhen; Gao, Cheng; Chen, Xuejiao; Kong, Wei; Kong, Deling; Zhao, Qiang

    2016-10-01

    Contractile vascular smooth muscle accounts for the normal physiological function of artery. Heparin, as a native glycosaminoglycan, has been well known for its important function in promoting or maintaining the contractile phenotype of vascular smooth muscle cells (VSMCs). In this study, heparin-functionalized non-woven poly(ε-caprolactone) (PCL) mat was fabricated by a facile and efficient surface modification protocol, which enables the control of surface heparin density within a broad range. Surface heparization remarkably increased the hydrophilicity of PCL, and reduced platelet adhesion. MTT assay showed that VSMC proliferation was evidently inhibited on the heparin-functionalized PCL surface in a dose-dependent manner. Gene analysis confirmed that surface heparization also promoted the transition of VSMCs from synthetic phenotype to contractile one. Furthermore, with a proper surface density of heparin, it allowed VSMCs to grow in a certain rate, while exhibiting contractile phenotype. Culture of VSMCs on a modified PCL mat with moderate heparin density (PCL-Hep-20) for 2 days resulted in a confluent layer of contractile smooth muscle cells. These data suggest that the heparin-modified PCL scaffolds may be a promising candidate to generate functional vascular tissues in vitro. PMID:27351139

  17. Netrin-1 overexpression in bone marrow mesenchymal stem cells promotes functional recovery in a rat model of peripheral nerve injury

    PubMed Central

    Ke, Xianjin; Li, Qian; Xu, Li; Zhang, Ying; Li, Dongmei; Ma, Jianhua; Mao, Xiaoming

    2015-01-01

    Abstract Transplantation of bone marrow mesenchymal stem cells (BMSCs) has been developed as a new method of treating diseases of the peripheral nervous system. While netrin-1 is a critical molecule for axonal path finding and nerve growth, it may also affect vascular network formation. Here, we investigated the effect of transplanting BMSCs that produce netrin-1 in a rat model of sciatic nerve crush injury. We introduced a sciatic nerve crush injury, and then injected 1×106 BMSCs infected by a recombinant adenovirus expressing netrin-1 Ad5-Netrin-1-EGFP or culture medium into the injured part in the next day. At day 7, 14 and 28 after injection, we measured motor nerve conduction and detected mRNA expressions of netrin-1 receptors UNC5B and Deleted in Colorectal Cancer (DCC), and neurotrophic factors brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) by real-time PCR. We also detected protein expressions of BDNF and NGF by Western blotting assays and examined BMSCs that incorporated into myelin and vascellum. The results showed that BMSCs infected by Ad5-Netrin-1-EGFP significantly improved the function of the sciatic nerve, and led to increased expression of BDNF and NGF (P<0.05). Moreover, 28 days after injury, more Schwann cells were found in BMSCs infected by Ad5-Netrin-1-EGFP compared to control BMSCs. In conclusion, transplantation of BMSCs that produce netrin-1 improved the function of the sciatic nerve after injury. This method may be a new treatment of nerve injury. PMID:26445571

  18. Engineering micropatterned surfaces to modulate the function of vascular stem cells

    SciTech Connect

    Li, Jennifer; Wu, Michelle; Chu, Julia; Sochol, Ryan; Patel, Shyam

    2014-02-21

    Highlights: • We examine vascular stem cell function on microgrooved and micropost patterned polymer substrates. • 10 μm microgrooved surfaces significantly lower VSC proliferation but do not modulate calcified matrix deposition. • Micropost surfaces significantly lower VSC proliferation and decrease calcified matrix deposition. - Abstract: Multipotent vascular stem cells have been implicated in vascular disease and in tissue remodeling post therapeutic intervention. Hyper-proliferation and calcified extracellular matrix deposition of VSC cause blood vessel narrowing and plaque hardening thereby increasing the risk of myocardial infarct. In this study, to optimize the surface design of vascular implants, we determined whether micropatterned polymer surfaces can modulate VSC differentiation and calcified matrix deposition. Undifferentiated rat VSC were cultured on microgrooved surfaces of varied groove widths, and on micropost surfaces. 10 μm microgrooved surfaces elongated VSC and decreased cell proliferation. However, microgrooved surfaces did not attenuate calcified extracellular matrix deposition by VSC cultured in osteogenic media conditions. In contrast, VSC cultured on micropost surfaces assumed a dendritic morphology, were significantly less proliferative, and deposited minimal calcified extracellular matrix. These results have significant implications for optimizing the design of cardiovascular implant surfaces.

  19. Construction of a fucoidan/laminin functional multilayer to direction vascular cell fate and promotion hemocompatibility.

    PubMed

    Ye, Changrong; Wang, Yan; Su, Hong; Yang, Ping; Huang, Nan; F Maitz, Manfred; Zhao, Anshan

    2016-07-01

    Surface biofunctional modification of cardiovascular stents is a versatile approach to reduce the adverse effects after implantation. In this work, a novel multifunctional coating was fabricated by coimmobilization of the sulfated polysaccharide of brown algae fucoidan and laminin to biomimic the vascular intimal conditions in order to support rapid endothelialization, prevent restenosis and improve hemocompatibility. The surface properties of the coating such as hydrophilicity, bonding density of biomolecules and stability were evaluated and optimized. According to the biocompatibility tests, the fucoidan/laminin multilayer coated surface displayed less platelet adhesion with favorable anticoagulant property. In addition, the fucoidan/laminin complex showed function to selectively regulate vascular cells growth behavior. The proliferation of endothelial cells (ECs) on the fucoidan/laminin biofunctional coating was significantly promoted. For the smooth muscle cells (SMCs), inhibitory effects on cell adhesion and proliferation were observed. In conclusion, the fucoidan/laminin biofunctional coating was successfully fabricated with desirable anticoagulant and endothelialization properties which show a promising application in the vascular devices such as vascular stents or grafts surface modification. PMID:27127049

  20. Thrombospondin-1 domain-containing peptide properdistatin improves vascular function in human melanoma xenografts.

    PubMed

    Gaustad, Jon-Vidar; Simonsen, Trude G; Andersen, Lise Mari K; Rofstad, Einar K

    2015-03-01

    Properdistatin is a novel peptide derived from the thrombospondin-1 domain of the plasma protein properdin. The purpose of this study was to investigate the effect of properdistatin treatment on the morphology and function of tumor vasculature. A-07 human melanoma xenografts grown in dorsal window chambers were used as preclinical model. Tumors were treated with 80 mg/kg/day properdistatin or vehicle for 4 days. Morphologic parameters of tumor vascular networks were assessed from high-resolution transillumination images, and tumor blood supply time and plasma velocities were assessed from first-pass imaging movies recorded after a bolus of 155 kDa tetramethylrhodamine isothiocyanate-labeled dextran had been administered intravenously. Properdistatin-treated tumors showed reduced density of small-diameter vessels, reduced blood supply time, and increased plasma velocities. In conclusion, properdistatin treatment inhibited angiogenesis and improved vascular function in A-07 tumors. PMID:24555949

  1. Vascular Function, Inflammation, and Variations in Cardiac Autonomic Responses to Particulate Matter Among Welders

    PubMed Central

    Cavallari, Jennifer M.; Eisen, Ellen A.; Chen, Jiu-Chiuan; Mittleman, Murray A.; Christiani, David C.

    2009-01-01

    Patients with health conditions associated with impaired vascular function and inflammation may be more susceptible to the adverse health effects of fine particulate (particulate matter with a mass median aerodynamic diameter of ≤2.5 μm (PM2.5)) exposure. In 2006, the authors conducted a panel study to investigate directly whether vascular function and inflammation (assessed by C-reactive protein) modify PM2.5-associated reductions in heart rate variability among 23 young male workers (mean age, 40 years) from Massachusetts. Concurrent 24-hour ambulatory electrocardiogram and personal PM2.5 exposure information was collected over a total of 36 person-days, including either or both welding and nonwelding days. Linear mixed models were used to examine the 5-minute standard deviation of normal-to-normal intervals (SDNN) in relation to the moving PM2.5 averages in the preceding 1–4 hours. C-reactive protein levels and 3 measures of vascular function (augmentation index, mean arterial pressure, and pulse pressure) were determined at baseline. The authors observed an inverse association between the 1-hour PM2.5 and 5-minute SDNN. Greater SDNN declines were observed among those with C-reactive protein (Pinteraction < 0.001) and augmentation index (P = 0.06) values at or above the 75th percentile and pulse pressure values below the 75th percentile (P < 0.001). Systemic inflammation and poorer vascular function appear to aggravate particle-related declines in heart rate variability among workers. PMID:19153215

  2. The CRC orthologue from Pisum sativum shows conserved functions in carpel morphogenesis and vascular development

    PubMed Central

    Fourquin, Chloé; Primo, Amparo; Martínez-Fernández, Irene; Huet-Trujillo, Estefanía; Ferrándiz, Cristina

    2014-01-01

    Background and Aims CRABS CLAW (CRC) is a member of the YABBY family of transcription factors involved in carpel morphogenesis, floral determinacy and nectary specification in arabidopsis. CRC orthologues have been functionally characterized across angiosperms, revealing additional roles in leaf vascular development and carpel identity specification in Poaceae. These studies support an ancestral role of CRC orthologues in carpel development, while roles in vascular development and nectary specification appear to be derived. This study aimed to expand research on CRC functional conservation to the legume family in order to better understand the evolutionary history of CRC orthologues in angiosperms. Methods CRC orthologues from Pisum sativum and Medicago truncatula were identified. RNA in situ hybridization experiments determined the corresponding expression patterns throughout flower development. The phenotypic effects of reduced CRC activity were investigated in P. sativum using virus-induced gene silencing. Key Results CRC orthologues from P. sativum and M. truncatula showed similar expression patterns, mainly restricted to carpels and nectaries. However, these expression patterns differed from those of other core eudicots, most importantly in a lack of abaxial expression in the carpel and in atypical expression associated with the medial vein of the ovary. CRC downregulation in pea caused defects in carpel fusion and style/stigma development, both typically associated with CRC function in eudicots, but also affected vascular development in the carpel. Conclusions The data support the conserved roles of CRC orthologues in carpel fusion, style/stigma development and nectary development. In addition, an intriguing new aspect of CRC function in legumes was the unexpected role in vascular development, which could be shared by other species from widely diverged clades within the angiosperms, suggesting that this role could be ancestral rather than derived, as so far

  3. Prevalence of peripheral arterial disease in subjects with moderate cardiovascular risk: Italian results from the PANDORA study Data from PANDORA (Prevalence of peripheral Arterial disease in subjects with moderate CVD risk, with No overt vascular Diseases nor Diabetes mellitus)

    PubMed Central

    2011-01-01

    Background The PANDORA study has recently examined the prevalence of low ankle brachial index (ABI) in subjects with moderate risk of cardiovascular disease. This sub-analysis of the PANDORA study examines the prevalence of asymptomatic peripheral arterial disease (PAD), as determined by ABI, in Italian subjects presenting with moderate cardiovascular risk, in the absence of diabetes or overt vascular disease. Methods PANDORA is a non-interventional, cross-sectional study that was performed in 6 European countries, involving subjects with at least one cardiovascular (CV) risk factor. The primary objective was to evaluate the prevalence of asymptomatic PAD using ABI. For this post-hoc sub-analysis, data were extracted for subjects enrolled in Italy, comprising 51.5% (n = 5298) of subjects from the original PANDORA study. Secondary objectives were to establish the prevalence and treatment of CV risk factors. Results The mean age was 63.9 years and 22.9% (95% CI 21.7-24.0) of subjects presented with asymptomatic PAD. A range of risk factors comprising smoking, hypertension, low HDL-cholesterol, family history of coronary heart disease and habit of moderate-high alcohol intake were significantly associated with asymptomatic PAD (p < 0.0001). Statin treatment had the lowest incidence in Italian subjects. Furthermore, patients treated with statins were significantly less likely to have asymptomatic PAD than those who were not (p = 0.0001). Conclusions Asymptomatic PAD was highly prevalent in Italian subjects, the majority of whom were not candidates for ABI assessment according to current guidelines. Findings from this study suggest that these patients should be carefully examined in clinical practice and ABI measured so that therapeutic interventions known to decrease their CV risk may be offered. Trial registration number ClinicalTrials.gov: NCT00689377 PMID:21981988

  4. Fenofibrate Improves Vascular Endothelial Function by Reducing Oxidative Stress While Increasing eNOS in Healthy Normolipidemic Older Adults

    PubMed Central

    Walker, Ashley E; Kaplon, Rachelle E; Lucking, Sara Marian S; Russell-Nowlan, Molly J; Eckel, Robert H; Seals, Douglas R

    2013-01-01

    Vascular endothelial dysfunction develops with aging, as indicated by impaired endothelium-dependent dilation(EDD), and is related to increased cardiovascular disease risk. We hypothesized that short-term treatment with fenofibrate, a lipid-lowering agent with potential pleiotropic effects, would improve EDD in middle-aged and older normolipidemic adults by reducing oxidative stress. Brachial artery flow-mediated dilation (FMD), a measure of EDD, was assessed in 22healthy adults aged 50-77 years before and after 7days of fenofibrate (145 mg/d; n=12/7M) or placebo (n=10/5M). Brachial FMD was unchanged with placebo, but improved after 2 and 7 days of fenofibrate (5.1±0.7 vs. 2d: 6.0±0.7 and 7d: 6.4±0.6 %Δ; both P<0.005). The improvements in FMD after 7 days remained significant (P<0.05) after accounting for modest changes in plasma total and LDL-cholesterol. Endothelium-independent dilation was not affected by fenofibrate or placebo (P>0.05). Infusion (i.v.) of the antioxidant vitamin C improved brachial FMD at baseline in both groups and during placebo treatment (P<0.05), but not after 2 and 7 days of fenofibrate (P>0.05). Fenofibrate treatment also reduced plasma oxidized LDL, a systemic marker of oxidative stress, compared with placebo (P<0.05). In vascular endothelial cells sampled from peripheral veins of the subjects, endothelial nitric oxide synthase (eNOS) protein expression was unchanged with placebo and after 2 days of fenofibrate, but was increased after 7 days of fenofibrate (0.54±0.03 vs. 2d: 0.52±0.04 and 7d: 0.76±0.11 intensity/HUVEC control; P<0.05 7d). Short-term treatment with fenofibrate improves vascular endothelial function in healthy normolipidemic middle-aged/older adults by reducing oxidative stress and induces increases in eNOS. PMID:23108655

  5. Nitrosylated Hemoglobin Levels in Human Venous Erythrocytes Correlate with Vascular Endothelial Function Measured by Digital Reactive Hyperemia

    PubMed Central

    Lobysheva, Irina I.; Biller, Pauline; Gallez, Bernard; Beauloye, Christophe; Balligand, Jean-Luc

    2013-01-01

    Impaired nitric oxide (NO)–dependent endothelial function is associated with the development of cardiovascular diseases. We hypothesized that erythrocyte levels of nitrosylated hemoglobin (HbNO-heme) may reflect vascular endothelial function in vivo. We developed a modified subtraction method using Electron Paramagnetic Resonance (EPR) spectroscopy to identify the 5-coordinate α-HbNO (HbNO) concentration in human erythrocytes and examined its correlation with endothelial function assessed by peripheral arterial tonometry (PAT). Changes in digital pulse amplitude were measured by PAT during reactive hyperemia following brachial arterial occlusion in a group of healthy volunteers (50 subjects). Erythrocyte HbNO levels were measured at baseline and at the peak of hyperemia. We digitally subtracted an individual model EPR signal of erythrocyte free radicals from the whole EPR spectrum to unmask and quantitate the HbNO EPR signals. Results Mean erythrocyte HbNO concentration at baseline was 219+/−12 nmol/L (n = 50). HbNO levels and reactive hyperemia (RH) indexes were higher in female (free of contraceptive pills) than male subjects. We observed a dynamic increase of HbNO levels in erythrocytes isolated at 1–2 min of post-occlusion hyperemia (120+/−8% of basal levels); post-occlusion HbNO levels were correlated with basal levels. Both basal and post-occlusion HbNO levels were significantly correlated with reactive hyperemia (RH) indexes (r = 0.58; P<0.0001 for basal HbNO). Conclusion The study demonstrates quantitative measurements of 5-coordinate α-HbNO in human venous erythrocytes, its dynamic physiologic regulation and correlation with endothelial function measured by tonometry during hyperemia. This opens the way to further understanding of in vivo determinants of NO bioavailability in human circulation. PMID:24130774

  6. Phenotypic, Ultra-Structural, and Functional Characterization of Bovine Peripheral Blood Dendritic Cell Subsets

    PubMed Central

    Sei, Janet J.; Ochoa, Amanda S.; Bishop, Elizabeth; Barlow, John W.; Golde, William T.

    2014-01-01

    Dendritic cells (DC) are multi-functional cells that bridge the gap between innate and adaptive immune systems. In bovine, significant information is lacking on the precise identity and role of peripheral blood DC subsets. In this study, we identify and characterize bovine peripheral blood DC subsets directly ex vivo, without further in vitro manipulation. Multi-color flow cytometric analysis revealed that three DC subsets could be identified. Bovine plasmacytoid DC were phenotypically identified by a unique pattern of cell surface protein expression including CD4, exhibited an extensive endoplasmic reticulum and Golgi apparatus, efficiently internalized and degraded exogenous antigen, and were the only peripheral blood cells specialized in the production of type I IFN following activation with Toll-like receptor (TLR) agonists. Conventional DC were identified by expression of a different pattern of cell surface proteins including CD11c, MHC class II, and CD80, among others, the display of extensive dendritic protrusions on their plasma membrane, expression of very high levels of MHC class II and co-stimulatory molecules, efficient internalization and degradation of exogenous antigen, and ready production of detectable levels of TNF-alpha in response to TLR activation. Our investigations also revealed a third novel DC subset that may be a precursor of conventional DC that were MHC class II+ and CD11c−. These cells exhibited a smooth plasma membrane with a rounded nucleus, produced TNF-alpha in response to TLR-activation (albeit lower than CD11c+ DC), and were the least efficient in internalization/degradation of exogenous antigen. These studies define three bovine blood DC subsets with distinct phenotypic and functional characteristics which can be analyzed during immune responses to pathogens and vaccinations of cattle. PMID:25295753

  7. Predictive Value of Endothelial Function by Non-invasive Peripheral Arterial Tonometry for Coronary Artery Disease

    PubMed Central

    Matsuzawa, Yasushi; Li, Jing; Aoki, Tatsuo; Guddeti, Raviteja R.; Kwon, Taek-Geun; Cilluffo, Rebecca; Widmer, R. Jay.; Gulati, Rajiv; Lennon, Ryan J.; Lerman, Lilach O.; Lerman, Amir

    2014-01-01

    Background Endothelial dysfunction is a key step in the initiation and progression of atherosclerosis and subsequent cardiovascular complications. We examined whether peripheral endothelial function, as assessed by fingertip reactive hyperemia-peripheral arterial tonometry (RH-PAT) can provide additional clinical value to traditional risk factors for cardiovascular diseases in predicting coronary artery disease (CAD). Methods We included 118 stable patients who were referred for coronary angiography for chest pain evaluation or abnormal stress test. A natural logarithmic value of RH-PAT index (Ln_RHI) was obtained before cardiac catheterization by an independent operator. Significant CAD was defined as luminal stenosis ≥70% (≥50% at left main) and/or fractional flow reserve ≤0.80 in one or more major coronary arteries or their major branches. Results Levels of Ln_RHI were significantly lower in patients with CAD (n=60) compared to patients without CAD (n=58) (0.69±0.29 vs. 0.88±0.27, p<0.001). Ln_RHI was significantly associated with CAD independent from traditional risk factors (odds ratio [OR] for 0.1 decrease in Ln_RHI 1.25, 95% confidence interval [CI] 1.04 to 1.52, p=0.01). The net reclassification index was improved when Ln_RHI was added to traditional risk factors (0.62, 95% CI: 0.27 to 0.97, p=0.001). Conclusions Peripheral endothelial function, as assessed by RH-PAT, improved risk stratification when added to traditional risk factors. RH-PAT is potentially useful for identifying patients at high risk for CAD. PMID:25503420

  8. An adaptive transfer function for deriving the aortic pressure waveform from a peripheral artery pressure waveform.

    PubMed

    Swamy, Gokul; Xu, Da; Olivier, N Bari; Mukkamala, Ramakrishna

    2009-11-01

    We developed a new technique to mathematically transform a peripheral artery pressure (PAP) waveform distorted by wave reflections into the physiologically more relevant aortic pressure (AP) waveform. First, a transfer function relating PAP to AP is defined in terms of the unknown parameters of a parallel tube model of pressure and flow in the arterial tree. The parameters are then estimated from the measured PAP waveform along with a one-time measurement of the wave propagation delay time between the aorta and peripheral artery measurement site (which may be accomplished noninvasively) by exploiting preknowledge of aortic flow. Finally, the transfer function with its estimated parameters is applied to the measured waveform so as to derive the AP waveform. Thus, in contrast to the conventional generalized transfer function, the transfer function is able to adapt to the intersubject and temporal variability of the arterial tree. To demonstrate the feasibility of this adaptive transfer function technique, we performed experiments in 6 healthy dogs in which PAP and reference AP waveforms were simultaneously recorded during 12 different hemodynamic interventions. The AP waveforms derived by the technique showed agreement with the measured AP waveforms (overall total waveform, systolic pressure, and pulse pressure root mean square errors of 3.7, 4.3, and 3.4 mmHg, respectively) statistically superior to the unprocessed PAP waveforms (corresponding errors of 8.6, 17.1, and 20.3 mmHg) and the AP waveforms derived by two previously proposed transfer functions developed with a subset of the same canine data (corresponding errors of, on average, 5.0, 6.3, and 6.7 mmHg). PMID:19783780

  9. Circulating Adipokines and Vascular Function: Cross-Sectional Associations in a Community-Based Cohort.

    PubMed

    Zachariah, Justin P; Hwang, Susan; Hamburg, Naomi M; Benjamin, Emelia J; Larson, Martin G; Levy, Daniel; Vita, Joseph A; Sullivan, Lisa M; Mitchell, Gary F; Vasan, Ramachandran S

    2016-02-01

    Adipokines may be potential mediators of the association between excess adiposity and vascular dysfunction. We assessed the cross-sectional associations of circulating adipokines with vascular stiffness in a community-based cohort of younger adults. We related circulating concentrations of leptin and leptin receptor, adiponectin, retinol-binding protein 4, and fatty acid-binding protein 4 to vascular stiffness measured by arterial tonometry in 3505 Framingham Third Generation cohort participants free of cardiovascular disease (mean age 40 years, 53% women). Separate regression models estimated the relations of each adipokine to mean arterial pressure and aortic stiffness, as carotid femoral pulse wave velocity, adjusting for age, sex, smoking, heart rate, height, antihypertensive treatment, total and high-density lipoprotein cholesterol, diabetes mellitus, alcohol consumption, estimated glomerular filtration rate, glucose, and C-reactive protein. Models evaluating aortic stiffness also were adjusted for mean arterial pressure. Mean arterial pressure was positively associated with blood retinol-binding protein 4, fatty acid-binding protein 4, and leptin concentrations (all P<0.001) and inversely with adiponectin (P=0.002). In fully adjusted models, mean arterial pressure was positively associated with retinol-binding protein 4 and leptin receptor levels (P<0.002 both). In fully adjusted models, aortic stiffness was positively associated with fatty acid-binding protein 4 concentrations (P=0.02), but inversely with leptin and leptin receptor levels (P≤0.03 both). In our large community-based sample, circulating concentrations of select adipokines were associated with vascular stiffness measures, consistent with the hypothesis that adipokines may influence vascular function and may contribute to the relation between obesity and hypertension. PMID:26628673

  10. Assessment of vascular function in Mexican women exposed to polycyclic aromatic hydrocarbons from wood smoke.

    PubMed

    Ruiz-Vera, Tania; Pruneda-Álvarez, Lucia G; Ochoa-Martínez, Ángeles C; Ramírez-GarcíaLuna, José L; Pierdant-Pérez, Mauricio; Gordillo-Moscoso, Antonio A; Pérez-Vázquez, Francisco J; Pérez-Maldonado, Iván N

    2015-09-01

    The use of solid fuels for cooking and heating is likely to be the largest source of indoor air pollution on a global scale; these fuels emit substantial amounts of toxic pollutants such as polycyclic aromatic hydrocarbons (PAHs) when used in simple cooking stoves (such as open "three-stone" fires). Moreover, indoor air pollution from biomass fuels is considered an important risk factor for human health. The aim of this study was to evaluate the relationship between exposure to PAHs from wood smoke and vascular dysfunction; in a group of Mexican women that use biomass combustion as their main energy source inside their homes. We used 1-hydroxypyrene (1-OHP) as an exposure biomarker to PAHs and it was assessed using high performance liquid chromatography. The endothelium-dependent vasodilation was assessed through a vascular reactivity compression test performed with a pneumatic cuff under visualization of the brachial artery using high resolution ultrasonography (HRU). Assessment of the carotid intima-media thickness (CIMT) was used as an atherosclerosis biomarker (also assessed using HRU); and clinical parameters such as anthropometry, blood pressure, glucose, triglycerides, total cholesterol, HDL cholesterol, LDL cholesterol, among others were also evaluated. The mean concentration of urinary 1-OHP found in exposed women was 0.46±0.32μmol/mol Cr (range: 0.086-1.23μmol/mol Cr). Moreover, vascular dysfunction (diminished endothelium dependent vasodilation) was found in 45% of the women participating in the study. Association between vascular function and 1-OHP levels was found to be significant through a logistic regression analysis (p=0.034; r(2)=0.1329). Furthermore, no association between CIMT and clinical parameters, urinary 1-OHP levels or vascular dysfunction was found. Therefore, with the information obtained in this study, we advocate for the need to implement programs to reduce the risk of exposure to PAHs in communities that use biomass fuels as a main

  11. The role of vascular biomarkers for primary and secondary prevention. A position paper from the European Society of Cardiology Working Group on peripheral circulation: Endorsed by the Association for Research into Arterial Structure and Physiology (ARTERY) Society.

    PubMed

    Vlachopoulos, Charalambos; Xaplanteris, Panagiotis; Aboyans, Victor; Brodmann, Marianne; Cífková, Renata; Cosentino, Francesco; De Carlo, Marco; Gallino, Augusto; Landmesser, Ulf; Laurent, Stéphane; Lekakis, John; Mikhailidis, Dimitri P; Naka, Katerina K; Protogerou, Athanasios D; Rizzoni, Damiano; Schmidt-Trucksäss, Arno; Van Bortel, Luc; Weber, Thomas; Yamashina, Akira; Zimlichman, Reuven; Boutouyrie, Pierre; Cockcroft, John; O'Rourke, Michael; Park, Jeong Bae; Schillaci, Giuseppe; Sillesen, Henrik; Townsend, Raymond R

    2015-08-01

    While risk scores are invaluable tools for adapted preventive strategies, a significant gap exists between predicted and actual event rates. Additional tools to further stratify the risk of patients at an individual level are biomarkers. A surrogate endpoint is a biomarker that is intended as a substitute for a clinical endpoint. In order to be considered as a surrogate endpoint of cardiovascular events, a biomarker should satisfy several criteria, such as proof of concept, prospective validation, incremental value, clinical utility, clinical outcomes, cost-effectiveness, ease of use, methodological consensus, and reference values. We scrutinized the role of peripheral (i.e. not related to coronary circulation) noninvasive vascular biomarkers for primary and secondary cardiovascular disease prevention. Most of the biomarkers examined fit within the concept of early vascular aging. Biomarkers that fulfill most of the criteria and, therefore, are close to being considered a clinical surrogate endpoint are carotid ultrasonography, ankle-brachial index and carotid-femoral pulse wave velocity; biomarkers that fulfill some, but not all of the criteria are brachial ankle pulse wave velocity, central haemodynamics/wave reflections and C-reactive protein; biomarkers that do no not at present fulfill essential criteria are flow-mediated dilation, endothelial peripheral arterial tonometry, oxidized LDL and dysfunctional HDL. Nevertheless, it is still unclear whether a specific vascular biomarker is overly superior. A prospective study in which all vascular biomarkers are measured is still lacking. In selected cases, the combined assessment of more than one biomarker may be required. PMID:26117398

  12. Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves.

    PubMed

    Colom, Bartomeu; Poitelon, Yannick; Huang, Wenlong; Woodfin, Abigail; Averill, Sharon; Del Carro, Ubaldo; Zambroni, Desirée; Brain, Susan D; Perretti, Mauro; Ahluwalia, Amrita; Priestley, John V; Chavakis, Triantafyllos; Imhof, Beat A; Feltri, M Laura; Nourshargh, Sussan

    2012-03-01

    Junctional adhesion molecule-C (JAM-C) is an adhesion molecule expressed at junctions between adjacent endothelial and epithelial cells and implicated in multiple inflammatory and vascular responses. In addition, we recently reported on the expression of JAM-C in Schwann cells (SCs) and its importance for the integrity and function of peripheral nerves. To investigate the role of JAM-C in neuronal functions further, mice with a specific deletion of JAM-C in SCs (JAM-C SC KO) were generated. Compared to wild-type (WT) controls, JAM-C SC KO mice showed electrophysiological defects, muscular weakness, and hypersensitivity to mechanical stimuli. In addressing the underlying cause of these defects, nerves from JAM-C SC KO mice were found to have morphological defects in the paranodal region, exhibiting increased nodal length as compared to WTs. The study also reports on previously undetected expressions of JAM-C, namely on perineural cells, and in line with nociception defects of the JAM-C SC KO animals, on finely myelinated sensory nerve fibers. Collectively, the generation and characterization of JAM-C SC KO mice has provided unequivocal evidence for the involvement of SC JAM-C in the fine organization of peripheral nerves and in modulating multiple neuronal responses. PMID:22090315

  13. Electrical stimulation accelerates axonal and functional peripheral nerve regeneration across long gaps.

    PubMed

    Haastert-Talini, Kirsten; Schmitte, Ruth; Korte, Nele; Klode, Dorothee; Ratzka, Andreas; Grothe, Claudia

    2011-04-01

    Short-term low-frequency electrical stimulation (ESTIM) of proximal peripheral nerve stumps prior to end-to-end coaptation or tubular bridging of small distances has been reported to increase preferential motor reinnervation and functional motor recovery in animal models and human patients undergoing carpal tunnel release surgery. We investigated the effects of ESTIM on regeneration across rat sciatic nerve gaps, which exceed distances that allow spontaneous regeneration. Three different reconstruction approaches were combined with ESTIM in the experimental groups. Nerve gaps (13 mm) were bridged using (I) nerve autotransplantation, (II) transplantation of differentially filled silicone tubes, or (III) transplantation of tubular grafts containing fibroblast growth factor-2 overexpressing Schwann cells (SCs) for gene therapy. The regeneration outcome was followed for up to 8 weeks, and functionally as well as histomorphometrically analyzed in comparison to non-stimulated control groups. Combining ESTIM with nerve autotransplantation significantly increased the nerve fiber density in the regenerated nerve, and the grade of functional recovery as detected by electrodiagnostic recordings from the gastrocnemius muscle. The combination of ESTIM with transplantation of naïve SCs increased the regeneration of gap-bridging nerve tissue. Although macroscopic tissue regeneration was not further improved after combining ESTIM with FGF-2(21/23-kD) gene therapy, the latter resulted in a high rate of regenerated nerves that functionally reconnected to the target muscle. Based on our results, brief ESTIM shows high potential to accelerate axonal as well as functional (motor and sensory) outcomes in the clinical setting of peripheral nerve gap reconstruction in human patients. PMID:21265597

  14. The effect of age on the relationship between cardiac and vascular function

    PubMed Central

    Houghton, David; Jones, Thomas W.; Cassidy, Sophie; Siervo, Mario; MacGowan, Guy A.; Trenell, Michael I.; Jakovljevic, Djordje G.

    2016-01-01

    Age-related changes in cardiac and vascular function are associated with increased risk of cardiovascular mortality and morbidity. The aim of the present study was to define the effect of age on the relationship between cardiac and vascular function. Haemodynamic and gas exchange measurements were performed at rest and peak exercise in healthy individuals. Augmentation index was measured at rest. Cardiac power output, a measure of overall cardiac function, was calculated as the product of cardiac output and mean arterial blood pressure. Augmentation index was significantly higher in older than younger participants (27.7 ± 10.1 vs. 2.5 ± 10.1%, P < 0.01). Older people demonstrated significantly higher stroke volume and mean arterial blood pressure (P < 0.05), but lower heart rate (145 ± 13 vs. 172 ± 10 beats/min, P < 0.01) and peak oxygen consumption (22.5 ± 5.2 vs. 41.2 ± 8.4 ml/kg/min, P < 0.01). There was a significant negative relationship between augmentation index and peak exercise cardiac power output (r = −0.73, P = 0.02) and cardiac output (r = −0.69, P = 0.03) in older participants. Older people maintain maximal cardiac function due to increased stroke volume. Vascular function is a strong predictor of overall cardiac function in older but in not younger people. PMID:26590322

  15. Antioxidative effect of aspirin on vascular function of aged ovariectomized rats.

    PubMed

    Demirci, Buket; Demir, Omer; Dost, Turhan; Birincioglu, Mustafa

    2014-02-01

    This study investigated the vascular effects of nonsteroidal anti-inflammatory drugs (NSAIDs) in the very late stage of postmenopausal vascular aging and looked for a better choice of anti-inflammatory drug for women in reducing the cardiovascular risk by decreasing the oxidant status in this term. The rat aorta isolated from young and old rats that were treated with either aspirin (10 mg/kg/day) or indomethacin (INDO, 1 mg/kg/day) within last 10 weeks after 16-month overiectomy (OVX) follow-up. Endothelium-dependant acetylcholine (Ach, 0.001-30 μM) and independent sodium nitroprusside (SNP, 0.0001-3 μM) relaxant; α-receptor phenylephrine (PE, 0.001-30 μM) and voltage-dependant high potassium (KCl; 40 mM) contractile responses were assessed. Total oxidant and antioxidant status were measured from the serum samples. Aged OVX rat's both aortic endothelium and smooth muscle relaxation were significantly less than of younger ones, whereas their contractile functions tended to decrease. INDO did not treat the Ach, SNP responses, whereas it increased the PE and KCl contractility. Aspirin improved the relaxation function and antioxidant capacity and decreased the oxidant status. These data demonstrate that even if they are in the very late stage of life and menopause, the analgesic choices could restore the well established endothelial dysfunction, vascular stiffness, and oxidant status. PMID:23872923

  16. Functions of Müller cell-derived vascular endothelial growth factor in diabetic retinopathy

    PubMed Central

    Wang, Juan-Juan; Zhu, Meili; Le, Yun-Zheng

    2015-01-01

    Müller cells are macroglia and play many essential roles as supporting cells in the retina. To respond to pathological changes in diabetic retinopathy (DR), a major complication in the eye of diabetic patients, retinal Müller glia produce a high level of vascular endothelial growth factor (VEGF or VEGF-A). As VEGF is expressed by multiple retinal cell-types and Müller glia comprise only a small portion of cells in the retina, it has been a great challenge to reveal the function of VEGF or other globally expressed proteins produced by Müller cells. With the development of conditional gene targeting tools, it is now possible to dissect the function of Müller cell-derived VEGF in vivo. By using conditional gene targeting approach, we demonstrate that Müller glia are a major source of retinal VEGF in diabetic mice and Müller cell-derived VEGF plays a significant role in the alteration of protein expression and peroxynitration, which leads to retinal inflammation, neovascularization, vascular leakage, and vascular lesion, key pathological changes in DR. Therefore, Müller glia are a potential cellular target for the treatment of DR, a leading cause of blindness. PMID:26069721

  17. Vascular smooth muscle in hypertension.

    PubMed

    Winquist, R J; Webb, R C; Bohr, D F

    1982-06-01

    The cause of the elevated arterial pressure in most forms of hypertension is an increase in total peripheral resistance. This brief review is directed toward an assessment of recent investigations contributing information about the factors responsible for this increased vascular resistance. Structural abnormalities in the vasculature that characterize the hypertensive process are 1) changes in the vascular media, 2) rarefication of the resistance vessels, and 3) lesions of the intimal vascular surface. These abnormalities are mainly the result of an adaptive process and are secondary to the increase in wall stress and/or to pathological damage to cellular components in the vessel wall. Functional alterations in the vascular smooth muscle are described as changes in agonist-smooth muscle interaction or plasma membrane permeability. These types of changes appear to play a primary, initiating role in the elevation of vascular resistance of hypertension. These alterations are not the result of an increase in wall stress and they often precede the development of high blood pressure. The functional changes are initiated by abnormal function of neurogenic, humoral, and/or myogenic changes that alter vascular smooth muscle activity. PMID:6282652

  18. [Cerebral hemodynamics and statokinetic functions in patients with vertebral basilar vascular insufficiency].

    PubMed

    Butko, D Iu

    2004-01-01

    One hundred and forty-eight patients, aged 29-59 years, with vertebral basilar vascular insufficiency were studied before, during and after betaserc treatment in a dose 48 mg/day during 3 weeks. Along with neurological examination, cerebral dopplerography and computer stabilography methods were used. The main clinical appearances of cerebrovascular pathology of vertebrobasilar system were as follows: vertigo (93.2%), asthenia syndrome (91.2%), autonomic vascular disorders (63.5%) and stato-coordinative disturbances, the latter were represented primarily by disturbances of equilibrium system functions (83.8%). Cerebral dopplerography and computer stabilography were found to be reliable methods for patients with chronic insufficiency of cerebral blood circulation in vertebral basilar area. Drug betaserc (betahystine hydrochloride) effectively stops statokinetic disturbances in patients with discirculatory encelopathy in vertebral basilar area. PMID:15847325

  19. Functional evaluation of peripheral nerve regeneration and target reinnervation in animal models: a critical overview.

    PubMed

    Navarro, Xavier

    2016-02-01

    Peripheral nerve injuries usually lead to severe loss of motor, sensory and autonomic functions in the patients. Due to the complex requirements for adequate axonal regeneration, functional recovery is often poorly achieved. Experimental models are useful to investigate the mechanisms related to axonal regeneration and tissue reinnervation, and to test new therapeutic strategies to improve functional recovery. Therefore, objective and reliable evaluation methods should be applied for the assessment of regeneration and function restitution after nerve injury in animal models. This review gives an overview of the most useful methods to assess nerve regeneration, target reinnervation and recovery of complex sensory and motor functions, their values and limitations. The selection of methods has to be adequate to the main objective of the research study, either enhancement of axonal regeneration, improving regeneration and reinnervation of target organs by different types of nerve fibres, or increasing recovery of complex sensory and motor functions. It is generally recommended to use more than one functional method for each purpose, and also to perform morphological studies of the injured nerve and the reinnervated targets. PMID:26228942

  20. Extracellular functional noncoding nucleic acid bioaptamers and angiotropin RNP ribokines in vascularization and self-tolerance.

    PubMed

    Wissler, Josef H; Wissler, Joerg E; Logemann, Enno

    2008-08-01

    Endogenous extracellular and circulating functional small noncoding nucleic acids (ncNAs; <200 nucleotides) and complexes with proteins (ribonucleoproteins; RNPs) make up varying biolibraries of molecular imprints of cellular histories. They are nascently formed upon cellular activation by extrinsic (environmental) factors, including mitogens, cell-mediated immune memory reactions (Landsteiner-Chase-Lawrence transfer factors), and metabolic (hypoxia) and (physical) shear stress forces. Those factors are conventional models for epigenetic (non-Mendelian) vascular remodeling variations directed rather to proteinaceous gene expression and regulation than genomic DNA sequence changes. Structurally defined ncNAs are described as small hairpin nc-shRNA bioaptamers in interaction with proteins forming functional (Cu,Ca,Na,K)-metalloregulated complexes (CuRNP; angiotropins). As nonmitogenic angiomorphogen cytokines (ribokines), they may reprogram confluent quiescent (contact-inhibited) endothelial cell types to migratory, phagokinetically active phenotypes in the morphogenesis of tolerated neovascular patterns. Their functions in organized and mess-chaotic vascular patterns were investigated with regard to master gene, information, epigenetic, vascular, and tumor factors. Some ncNAs feature three-dimensional codes (3D episcripts) for distinct protein conformer phases. They are suggested as being specific recognition types, the estimated repertoires of which are superior in diversity and specificity to conventional immune (glyco-)proteins. For episcription of phenotype variations, they may address and integrate information flow on molecular shapes to protein-mediated nucleic acid processing and [post-]translational modification mechanisms in ncNA-, redox, and metalloregulated conformation phase pathway-locked loops (CPLL). Several vascular and cancer epigenetic regulator proteins are shown to be entangled by sharing helix-nucleating structural (proteomic) domains for

  1. Long-term Successful Weight Loss Improves Vascular Endothelial Function in Severely Obese Individuals

    PubMed Central

    Bigornia, Sherman J.; Mott, Melanie M.; Hess, Donald T.; Apovian, Caroline M.; McDonnell, Marie E.; Duess, Mai-Ann; Kluge, Matthew A.; Fiscale, Antonino J.; Vita, Joseph A.; Gokce, Noyan

    2010-01-01

    Obesity is associated with increased cardiovascular risk. Although short-term weight loss improves vascular endothelial function, longer term outcomes have not been widely investigated. We examined brachial artery endothelium-dependent vasodilation and metabolic parameters in 29 severely obese subjects who lost ≥10% body weight (age 45 ± 13 years; BMI 48 ± 9 kg/m2) at baseline and after 12 months of dietary and/or surgical intervention. We compared these parameters to 14 obese individuals (age 49 ± 11 years; BMI 39 ± 7 kg/m2) who failed to lose weight. For the entire group, mean brachial artery flow-mediated dilation (FMD) was impaired at 6.7 ± 4.1%. Following sustained weight loss, FMD increased significantly from 6.8 ± 4.2 to 10.0 ± 4.7%, but remained blunted in patients without weight decline from 6.5 ± 4.0 to 5.7 ± 4.1%, P = 0.013 by ANOVA. Endothelium-independent, nitroglycerin-mediated dilation (NMD) was unaltered. BMI fell by 13 ± 7 kg/m2 following successful weight intervention and was associated with reduced total and low-density lipoprotein cholesterol, glucose, hemoglobin A1c, and high-sensitivity C-reactive protein (CRP). Vascular improvement correlated most strongly with glucose levels (r = −0.51, P = 0.002) and was independent of weight change. In this cohort of severely obese subjects, sustained weight loss at 1 year improved vascular function and metabolic parameters. The findings suggest that reversal of endothelial dysfunction and restoration of arterial homeostasis could potentially reduce cardiovascular risk. The results also demonstrate that metabolic changes in association with weight loss are stronger determinants of vascular phenotype than degree of weight reduction. PMID:20057371

  2. Functional spectroscopy approach to the assessment of nitric oxide storage in vascular tissues

    NASA Astrophysics Data System (ADS)

    Rodriguez, Juan; Feelisch, Martin

    2003-10-01

    Much attention has been devoted to the enzymatic production of nitric oxide (NO) by the endothelial layer lining blood vessel walls, which regulates among other things local vasodilatation and platelet adhesion. Considerably less attention, however, has been paid to the accumulation of NO-related products in the vascular wall itself. Such local storage of NO products could conceivably contribute to the local regulation of blood flow and provide additional anti-adhesive protection, if biochemically activated to regenerate NO. Since little is known about their chemical nature, concentrations, and possible role in vascular biology we sought to characterize those species basally resent in rat aorta. To this end we developed a functional form of optical spectroscopy that allows us not only to identify NO-stores in intact tissues but also to monitor their production and disappearance in real-time. The method is based on the ability of NO stores to reversibly release NO when illuminated with light of particular wavelengths, which can be detected as a robust relaxation of vascular smooth muscle (photorelaxation). Characterization of NO-stores is achieved through a careful assessment of photorelaxation action spectra, taking into account the light scattering properties of the tissue, and of depletion of the NO-stores induced by exposure to controlled levels of light. This functional form of optical spectroscopy is applied to rat aortic tissue where the results suggest that the NO photolytically released from tissue stores originated from a low-molecular-weight RSNO as well as from nitrite. The significance of these findings to vascular physiology and pathophysiology is discussed.

  3. The effect of altered peripheral field on motoneurone function in developing rat soleus muscles.

    PubMed Central

    Lowrie, M B; O'Brien, R A; Vrbová, G

    1985-01-01

    In soleus muscles of 4- to 5-day-old rats the quantum content of axon terminals from L4 spinal roots is less than half that from L5. With development the size of L4 motor units decreases and the quantum content of L4 nerves increases to become similar to that of L5 axons. During this time the overlap of territories of L4 and L5 axons is reduced from 46% at 4-6 days to 2% at 18-20 days. This reduction occurs entirely at the expense of L4 territory. Removal of the L5 ventral ramus (v.r.) at 4-6 days prevents the reduction of L4 territory so that at 18 days L4 motor units are about 4 X normal size. In spite of this enlarged peripheral field of L4 axons the quantum content of their terminals increases to normal levels. When L5 v.r. was removed at 16-18 days, i.e. when the reduction of the L4 peripheral field was complete, expansion of L4 motor units was also seen, but in this case the quantum content of L4 terminals was less than normal. Thus it appears that during early stages of development, before synaptic reorganization within the muscle is complete, motoneurones are able to adapt their function to increased peripheral demands more effectively than at later stages of post-natal development. Retrograde labelling of soleus motor pool with horseradish peroxidase (HRP) showed that removal of L5 v.r. either at 4 or 15 days of age reduced the number of motoneurones supplying soleus muscle to less than 20%. No change in size of the remaining motoneurones was seen, indicating that the adjustment of transmitter output at the neuromuscular junctions in the younger group had no effect on the size of the cell. PMID:2867219

  4. The role of mechanotransduction on vascular smooth muscle myocytes' [corrected] cytoskeleton and contractile function.

    PubMed

    Ye, George J C; Nesmith, Alexander P; Parker, Kevin Kit

    2014-09-01

    Smooth muscle (SM) exhibits a highly organized structural hierarchy that extends over multiple spatial scales to perform a wide range of functions at the cellular, tissue, and organ levels. Early efforts primarily focused on understanding vascular SM (VSM) function through biochemical signaling. However, accumulating evidence suggests that mechanotransduction, the process through which cells convert mechanical stimuli into biochemical cues, is requisite for regulating contractility. Cytoskeletal proteins that comprise the extracellular, intercellular, and intracellular domains are mechanosensitive and can remodel their structure and function in response to external mechanical cues. Pathological stimuli such as malignant hypertension can act through the same mechanotransductive pathways to induce maladaptive remodeling, leading to changes in cellular shape and loss of contractile function. In both health and disease, the cytoskeletal architecture integrates the mechanical stimuli and mediates structural and functional remodeling in the VSM. PMID:25125187

  5. Acute Effect of High-Intensity Eccentric Exercise on Vascular Endothelial Function in Young Men.

    PubMed

    Choi, Youngju; Akazawa, Nobuhiko; Zempo-Miyaki, Asako; Ra, Song-Gyu; Shiraki, Hitoshi; Ajisaka, Ryuichi; Maeda, Seiji

    2016-08-01

    Choi, Y, Akazawa, N, Zempo-Miyaki, A, Ra, S-G, Shiraki, H, Ajisaka, R, and Maeda, S. Acute effect of high-intensity eccentric exercise on vascular endothelial function in young men. J Strength Cond Res 30(8): 2279-2285, 2016-Increased central arterial stiffness is as an independent risk factor for cardiovascular disease. Evidence regarding the effects of high-intensity resistance exercise on vascular endothelial function and central arterial stiffness is conflicting. The purpose of this study was to examine the effects of acute high-intensity eccentric exercise on vascular endothelial function and central arterial stiffness. We evaluated the acute changes in endothelium-dependent flow-mediated dilation (FMD), low-flow-mediated constriction (L-FMC), and arterial stiffness after high-intensity eccentric exercise. Seven healthy, sedentary men (age, 24 ± 1 year) performed maximal eccentric elbow flexor exercise using their nondominant arm. Before and 45 minutes after eccentric exercise, carotid arterial compliance and brachial artery FMD and L-FMC in the nonexercised arm were measured. Carotid arterial compliance was significantly decreased, and β-stiffness index significantly increased after eccentric exercise. Brachial FMD was significantly reduced after eccentric exercise, whereas there was no significant difference in brachial L-FMC before and after eccentric exercise. A positive correlation was detected between change in arterial compliance and change in FMD (r = 0.779; p ≤ 0.05), and a negative correlation was detected between change in β-stiffness index and change in FMD (r = -0.891; p < 0.01) with eccentric exercise. In this study, acute high-intensity eccentric exercise increased central arterial stiffness; this increase was accompanied by a decrease in endothelial function caused by reduced endothelium-dependent vasodilation but not by a change in endothelium-dependent vasoconstriction. PMID:24832967

  6. Experimental studies of mitochondrial function in CADASIL vascular smooth muscle cells

    SciTech Connect

    Viitanen, Matti; Sundström, Erik; Baumann, Marc; Tikka, Saara

    2013-02-01

    Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a familiar fatal progressive degenerative disorder characterized by cognitive decline, and recurrent stroke in young adults. Pathological features include a dramatic reduction of brain vascular smooth muscle cells and severe arteriopathy with the presence of granular osmophilic material in the arterial walls. Here we have investigated the cellular and mitochondrial function in vascular smooth muscle cell lines (VSMCs) established from CADASIL mutation carriers (R133C) and healthy controls. We found significantly lower proliferation rates in CADASIL VSMC as compared to VSMC from controls. Cultured CADASIL VSMCs were not more vulnerable than control cells to a number of toxic substances. Morphological studies showed reduced mitochondrial connectivity and increased number of mitochondria in CADASIL VSMCs. Transmission electron microscopy analysis demonstrated increased irregular and abnormal mitochondria in CADASIL VSMCs. Measurements of mitochondrial membrane potential (Δψ{sub m}) showed a lower percentage of fully functional mitochondria in CADASIL VSMCs. For a number of genes previously reported to be changed in CADASIL VSMCs, immunoblotting analysis demonstrated a significantly reduced SOD1 expression. These findings suggest that alteration of proliferation and mitochondrial function in CADASIL VSMCs might have an effect on vital cellular functions important for CADASIL pathology. -- Highlights: ► CADASIL is an inherited disease of cerebral vascular cells. ► Mitochondrial dysfunction has been implicated in the pathogenesis of CADASIL. ► Lower proliferation rates in CADASIL VSMC. ► Increased irregular and abnormal mitochondria and lower mitochondrial membrane potential in CADASIL VSMCs. ► Reduced mitochondrial connectivity and increased number of mitochondria in CADASIL VSMCs.

  7. Pravastatin ameliorates placental vascular defects, fetal growth, and cardiac function in a model of glucocorticoid excess.

    PubMed

    Wyrwoll, Caitlin S; Noble, June; Thomson, Adrian; Tesic, Dijana; Miller, Mark R; Rog-Zielinska, Eva A; Moran, Carmel M; Seckl, Jonathan R; Chapman, Karen E; Holmes, Megan C

    2016-05-31

    Fetoplacental glucocorticoid overexposure is a significant mechanism underlying fetal growth restriction and the programming of adverse health outcomes in the adult. Placental glucocorticoid inactivation by 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) plays a key role. We previously discovered that Hsd11b2(-/-) mice, lacking 11β-HSD2, show marked underdevelopment of the placental vasculature. We now explore the consequences for fetal cardiovascular development and whether this is reversible. We studied Hsd11b2(+/+), Hsd11b2(+/-), and Hsd11b2(-/-) littermates from heterozygous (Hsd11b(+/-)) matings at embryonic day (E)14.5 and E17.5, where all three genotypes were present to control for maternal effects. Using high-resolution ultrasound, we found that umbilical vein blood velocity in Hsd11b2(-/-) fetuses did not undergo the normal gestational increase seen in Hsd11b2(+/+) littermates. Similarly, the resistance index in the umbilical artery did not show the normal gestational decline. Surprisingly, given that 11β-HSD2 absence is predicted to initiate early maturation, the E/A wave ratio was reduced at E17.5 in Hsd11b2(-/-) fetuses, suggesting impaired cardiac function. Pravastatin administration from E6.5, which increases placental vascular endothelial growth factor A and, thus, vascularization, increased placental fetal capillary volume, ameliorated the aberrant umbilical cord velocity, normalized fetal weight, and improved the cardiac function of Hsd11b2(-/-) fetuses. This improved cardiac function occurred despite persisting indications of increased glucocorticoid exposure in the Hsd11b2(-/-) fetal heart. Thus, the pravastatin-induced enhancement of fetal capillaries within the placenta and the resultant hemodynamic changes correspond with restored fetal cardiac function. Statins may represent a useful therapeutic approach to intrauterine growth retardation due to placental vascular hypofunction. PMID:27185937

  8. Endothelial Cords Promote Tumor Initial Growth prior to Vascular Function through a Paracrine Mechanism

    PubMed Central

    Zhao, Chengjian; Zhang, Wei; Zhao, Yuwei; Yang, Yun; Luo, Hui; Ji, Gaili; Dong, E; Deng, Hongxing; Lin, Shuo; Wei, Yuquan; Yang, Hanshuo

    2016-01-01

    The angiogenic switch is an important oncogenic step that determines whether microtumors remain dormant or progresses further. It has been generally perceived that the primary function of this tumorgenic event is to supply oxygen and nutrients through blood circulation. Using in vivo imaging of zebrafish and mouse tumor models, we showed that endothelial cords aggressively penetrated into microtumors and remained non-circulatory for several days before undergoing vascular blood perfusion. Unexpectedly, we found that initial tumor growth in both models was significantly reduced if endothelial cords were removed by blocking VEGF-VEGFR2 signaling or using a vascular deficient zebrafish mutant. It was further shown that soluble factors including IL-8, secreted by endothelial cells (ECs) were responsible for stimulating tumor cells proliferation. These findings establish that tumor angiogenesis play a much earlier and broader role in promoting tumor growth, which is independent of vascular circulation. Understanding this novel mechanism of angiogenic tumor progression offers new entry points for cancer therapeutics. PMID:26762853

  9. External Volume Expansion Modulates Vascular Growth and Functional Maturation in a Swine Model

    PubMed Central

    Kao, Huang-Kai; Hsu, Hsiang-Hao; Chuang, Wen-Yu; Chen, Sheng-Chih; Chen, Bin; Wu, Shinn-Chih; Guo, Lifei

    2016-01-01

    Despite increasing application of the pre-grafting expansion during autologous fat transplantation in breast reconstruction, little is known about its mechanism of action. To address that, ventral skins of miniature pigs were treated over a 10-day or 21-day period, with continuous suction at −50 mm Hg via a 7-cm diameter rubber-lined suction-cup device. Soft tissue thickness increased immediately after this external volume expansion (EVE) treatment, such increase completely disappeared by the next day. In the dermis and subcutaneous fat, the EVE treated groups showed significant increases in blood vessel density evident by CD31 staining as well as in vascular networks layered with smooth muscle cells when compared with the control group. This finding was corroborated by the increased percentage of endothelial cells present in the treatment groups. There was no significant difference in the percentages of proliferating basal keratinocytes or adipocytes, nor in epidermal thickness. Moreover, the EVE had no effect on proliferation or differentiation potential of adipose stem cells. Taken together, the major effects of EVE appeared to be vascular remodeling and maturation of functional blood vessels. This understanding may help clinicians optimize the vascularity of the recipient bed to further improve fat graft survival. PMID:27174509

  10. External Volume Expansion Modulates Vascular Growth and Functional Maturation in a Swine Model.

    PubMed

    Kao, Huang-Kai; Hsu, Hsiang-Hao; Chuang, Wen-Yu; Chen, Sheng-Chih; Chen, Bin; Wu, Shinn-Chih; Guo, Lifei

    2016-01-01

    Despite increasing application of the pre-grafting expansion during autologous fat transplantation in breast reconstruction, little is known about its mechanism of action. To address that, ventral skins of miniature pigs were treated over a 10-day or 21-day period, with continuous suction at -50 mm Hg via a 7-cm diameter rubber-lined suction-cup device. Soft tissue thickness increased immediately after this external volume expansion (EVE) treatment, such increase completely disappeared by the next day. In the dermis and subcutaneous fat, the EVE treated groups showed significant increases in blood vessel density evident by CD31 staining as well as in vascular networks layered with smooth muscle cells when compared with the control group. This finding was corroborated by the increased percentage of endothelial cells present in the treatment groups. There was no significant difference in the percentages of proliferating basal keratinocytes or adipocytes, nor in epidermal thickness. Moreover, the EVE had no effect on proliferation or differentiation potential of adipose stem cells. Taken together, the major effects of EVE appeared to be vascular remodeling and maturation of functional blood vessels. This understanding may help clinicians optimize the vascularity of the recipient bed to further improve fat graft survival. PMID:27174509

  11. Peripheral, functional and postural asymmetries related to the preferred chewing side in adults with natural dentition.

    PubMed

    Rovira-Lastra, B; Flores-Orozco, E I; Ayuso-Montero, R; Peraire, M; Martinez-Gomis, J

    2016-04-01

    The aim of this cross-sectional study was to determine the preferred chewing side and whether chewing side preference is related to peripheral, functional or postural lateral preferences. One hundred and forty-six adults with natural dentition performed three masticatory assays, each consisting of five trials of chewing three pieces of silicon placed into a latex bag for 20 cycles, either freestyle or unilaterally on the right- or left-hand side. Occlusal contact area in the intercuspal position, maximum bite force, masticatory performance and cycle duration were measured and the lateral asymmetry of these variables was calculated. Laterality tests were performed to determine handedness, footedness, earedness and eyedness as functional preferences, and hand-clasping, arm-folding and leg-crossing as postural lateral preferences. The preferred chewing side was determined using three different methods: assessment of the first chewing cycle for each trial, calculation of the asymmetry index from all cycles and application of a visual analogue scale. Bivariate relationship and multiple linear regression analyses were performed. Among unilateral chewers, 77% of them preferred the right side for chewing. The factors most closely related to the preferred chewing side were asymmetry of bite force, asymmetry of masticatory performance and earedness, which explained up to 16% of the variance. Although several functional or postural lateral preferences seem to be related to the preferred chewing side, peripheral factors such as asymmetry of bite force and of masticatory performance are the most closely related to the preferred chewing side in adults with natural dentition. PMID:26549578

  12. On Cross-Sectional Associations of Leukocyte Telomere Length with Cardiac Systolic, Diastolic and Vascular Function: The Asklepios Study

    PubMed Central

    De Buyzere, Marc L.; Van daele, Caroline M.; Segers, Patrick; De Bacquer, Dirk; Van Criekinge, Wim; Bekaert, Sofie; Gillebert, Thierry C.; De Meyer, Tim

    2014-01-01

    Background Systemic telomere length has been associated with measures of diastolic function, vascular stiffness and left ventricular mass mainly in smaller, patient-specific settings and not in a general population. In this study we describe the applicability of these findings in a large, representative population. Methods and Results Peripheral blood leukocyte telomere length (PBL TL) was measured using telomere restriction fragment analysis in the young to middle-aged (>2500 volunteers, ∼35 to 55 years old) Asklepios study population, free from overt cardiovascular disease. Subjects underwent extensive echocardiographic, hemodynamic and biochemical phenotyping. After adjusting for relevant confounders (age, sex, systolic blood pressure, heart rate, body mass index and use of antihypertensive drugs) we found no associations between PBL TL and left ventricular mass index (P = 0.943), ejection fraction (P = 0.933), peak systolic septal annular motion (P = 0.238), pulse wave velocity (P = 0.971) or pulse pressure (P = 0.999). In contrast, our data showed positive associations between PBL TL and parameters of LV filling: the transmitral flow early (E) to late (A) velocity ratio (E/A-ratio; P<0.001), the ratio of early (e′) to late (a′) mitral annular velocities (e′/a′-ratio; P = 0.012) and isovolumic relaxation time (P = 0.015). Interestingly, these associations were stronger in women than in men and were driven by associations between PBL TL and the late diastolic components (A and a′). Conclusions In a generally healthy, young to middle-aged population, PBL TL is not related to LV mass or systolic function, but might be associated with an altered LV filling pattern, especially in women. PMID:25506937

  13. Short-term exercise training improves vascular function in hypercholesterolemic rabbit femoral artery.

    PubMed

    Jen, Chauying J; Liu, Yu-Fan; Chen, Hsiun-Ing

    2005-06-30

    Chronic exercise in healthy or hypercholesteremic animals for at least two months improves their vascular functions. This study is to examine whether short-term exercise training protocols can correct early-stage vascular dysfunction induced by high-cholesterol diet feeding. Male New Zealand White rabbits were fed for 2, 4 or 6 weeks with rabbit chow with or without the addition of 2% (w/w) cholesterol. They were further divided into control and exercise groups. Animals in exercise groups ran on a leveled treadmill for the same time periods as diet intervention. At the end of experiments, femoral arteries were dissected, loaded with fura 2-AM, and mounted in a tissue flow chamber. Phenylephrine-precontracted vessel specimens were exposed to acetylcholine. The endothelial intracellular calcium elevation and vasorelaxation were determined simultaneously under an epifluorescence microscope with ratio imaging capability. En face oil red O staining was used to evaluate fatty streak formation. Our results showed that 1) high-cholesterol diet feeding for > or = 4 weeks caused lipid deposition, reduced the acetylcholine-evoked endothelial calcium signaling, and impaired both endothelium-dependent and endothelium-independent vascular responses in a time-dependent manner; 2) vasorelaxation at given levels of endothelial intracellular calcium elevation decreased in hypercholesterolemia; 3) concomitant exercise program had reverse effects. We conclude that high-cholesterol diet intervention for as short as 4 weeks induces vascular structural changes, impairs endothelial intracellular calcium signaling and vasodilatation in rabbit femoral arteries. Short-term exercise training in parallel completely eliminates these adverse effects so long as the diet intervention is no more than 6 weeks. PMID:16201452

  14. Dissociation between neural and vascular responses to sympathetic stimulation : contribution of local adrenergic receptor function

    NASA Technical Reports Server (NTRS)

    Jacob, G.; Costa, F.; Shannon, J.; Robertson, D.; Biaggioni, I.

    2000-01-01

    Sympathetic activation produced by various stimuli, eg, mental stress or handgrip, evokes regional vascular responses that are often nonhomogeneous. This phenomenon is believed to be the consequence of the recruitment of differential central neural pathways or of a sympathetically mediated vasodilation. The purpose of this study was to determine whether a similar heterogeneous response occurs with cold pressor stimulation and to test the hypothesis that local differences in adrenergic receptor function could be in part responsible for this diversity. In 8 healthy subjects, local norepinephrine spillover and blood flow were measured in arms and legs at baseline and during sympathetic stimulation induced by baroreflex mechanisms (nitroprusside infusion) or cold pressor stimulation. At baseline, legs had higher vascular resistance (27+/-5 versus 17+/-2 U, P=0.05) despite lower norepinephrine spillover (0.28+/-0.04 versus 0.4+/-0.05 mg. min(-1). dL(-1), P=0.03). Norepinephrine spillover increased similarly in both arms and legs during nitroprusside infusion and cold pressor stimulation. On the other hand, during cold stimulation, vascular resistance increased in arms but not in legs (20+/-9% versus -7+/-4%, P=0.03). Increasing doses of isoproterenol and phenylephrine were infused intra-arterially in arms and legs to estimate beta-mediated vasodilation and alpha-induced vasoconstriction, respectively. beta-Mediated vasodilation was significantly lower in legs compared with arms. Thus, we report a dissociation between norepinephrine spillover and vascular responses to cold stress in lower limbs characterized by a paradoxical decrease in local resistance despite increases in sympathetic activity. The differences observed in adrenergic receptor responses cannot explain this phenomenon.

  15. What is the effect of peripheral muscle fatigue, pulmonary function, and body composition on functional exercise capacity in acromegalic patients?

    PubMed Central

    Lopes, Agnaldo José; Guedes da Silva, Débora Pedroza; Ferreira, Arthur de Sá; Kasuki, Leandro; Gadelha, Mônica Roberto; Guimarães, Fernando Silva

    2015-01-01

    [Purpose] The six-minute walk test (6MWT) is increasingly being used as an important tool for analyzing functional capacity in patients with multisystem disorders. The aim of this study was to evaluate the effect of body composition, peripheral muscle function, and pulmonary function on the six-minute walk distance (6MWD) in acromegalic patients. [Subjects and Methods] Thirty-two patients with active acromegaly, with a mean age of 48.6 ± 12.1 years, underwent an evaluation of body composition using electrical bioimpedance, isometric dynamometry with surface electromyography, tests of pulmonary function, and the 6MWT. [Results] The mean ± SD values for the 6MWD, fat-free mass (FFM), and maximal expiratory pressure (MEP) were 65.5 ± 11.7% predicted, 55.1 ± 10.6 kg, and 55.2 ± 16.8% predicted, respectively. There was a significant correlation between the 6MWD and the following parameters: the angle of the linear regression line obtained using the values of the median frequency electromyography signal over time during the fatigability test for the vastus medialis muscle (MDF, r=0.65), FFM (r=0.62), MEP (r=0.60), height(2)/resistance index (r=0.52), resistance (r=−0.50), and forced expiratory volume in 1 second (r=0.50). Multivariate analysis showed that MDF, FFM, and MEP were independent predictors of the 6MWD (R2=0.52). [Conclusion] The fatigability of the peripheral muscles, FFM, and MEP are the primary determinants of the 6MWD in acromegalics. PMID:25931716

  16. What is the effect of peripheral muscle fatigue, pulmonary function, and body composition on functional exercise capacity in acromegalic patients?

    PubMed

    Lopes, Agnaldo José; Guedes da Silva, Débora Pedroza; Ferreira, Arthur de Sá; Kasuki, Leandro; Gadelha, Mônica Roberto; Guimarães, Fernando Silva

    2015-03-01

    [Purpose] The six-minute walk test (6MWT) is increasingly being used as an important tool for analyzing functional capacity in patients with multisystem disorders. The aim of this study was to evaluate the effect of body composition, peripheral muscle function, and pulmonary function on the six-minute walk distance (6MWD) in acromegalic patients. [Subjects and Methods] Thirty-two patients with active acromegaly, with a mean age of 48.6 ± 12.1 years, underwent an evaluation of body composition using electrical bioimpedance, isometric dynamometry with surface electromyography, tests of pulmonary function, and the 6MWT. [Results] The mean ± SD values for the 6MWD, fat-free mass (FFM), and maximal expiratory pressure (MEP) were 65.5 ± 11.7% predicted, 55.1 ± 10.6 kg, and 55.2 ± 16.8% predicted, respectively. There was a significant correlation between the 6MWD and the following parameters: the angle of the linear regression line obtained using the values of the median frequency electromyography signal over time during the fatigability test for the vastus medialis muscle (MDF, r=0.65), FFM (r=0.62), MEP (r=0.60), height((2))/resistance index (r=0.52), resistance (r=-0.50), and forced expiratory volume in 1 second (r=0.50). Multivariate analysis showed that MDF, FFM, and MEP were independent predictors of the 6MWD (R(2)=0.52). [Conclusion] The fatigability of the peripheral muscles, FFM, and MEP are the primary determinants of the 6MWD in acromegalics. PMID:25931716

  17. Functional Mineralocorticoid Receptors in Human Vascular Endothelial Cells Regulate ICAM-1 Expression and Promote Leukocyte Adhesion

    PubMed Central

    Caprio, Massimiliano; Newfell, Brenna G.; la Sala, Andrea; Baur, Wendy; Fabbri, Andrea; Rosano, Giuseppe; Mendelsohn, Michael E.; Jaffe, Iris Z.

    2008-01-01

    In clinical trials, aldosterone antagonists decrease cardiovascular mortality and ischemia by unknown mechanisms. The steroid hormone aldosterone acts by binding to the mineralocorticoid receptor (MR), a ligand-activated transcription factor. In humans, aldosterone causes MR-dependent endothelial cell (EC) dysfunction and in animal models, aldosterone increases vascular macrophage infiltration and atherosclerosis. MR antagonists inhibit these effects without changing blood pressure, suggesting a direct role for vascular MR in EC function and atherosclerosis. Whether human vascular EC express functional MR is not known. Here we show that human coronary artery and aortic EC express MR mRNA and protein and that EC MR mediates aldosterone-dependent gene transcription. Human EC also express the enzyme 11-beta hydroxysteroid dehydrogenase-2(11βHSD2) and inhibition of 11βHSD2 in aortic EC enhances gene transactivation by cortisol, supporting that EC 11βHSD2 is functional. Furthermore, aldosterone stimulates transcription of the proatherogenic leukocyte-EC adhesion molecule Intercellular Adhesion Molecule-1(ICAM1) gene and protein expression on human coronary artery EC, an effect inhibited by the MR antagonist spironolactone and by MR knock-down with siRNA. Cell adhesion assays demonstrate that aldosterone promotes leukocyte-EC adhesion, an effect that is inhibited by spironolactone and ICAM1 blocking antibody, supporting that aldosterone induction of EC ICAM1 surface expression via MR mediates leukocyte-EC adhesion. These data show that aldosterone activates endogenous EC MR and proatherogenic gene expression in clinically important human EC. These studies describe a novel mechanism by which aldosterone may influence ischemic cardiovascular events and support a new explanation for the decrease in ischemic events in patients treated with aldosterone antagonists. PMID:18467630

  18. Proton pump inhibitors and vascular function: A prospective cross-over pilot study

    PubMed Central

    Ghebremariam, Yohannes T.; Cooke, John P.; Khan, Fouzia; Thakker, Rahul N.; Chang, Peter; Shah, Nigam H.; Nead, Kevin T.; Leeper, Nicholas J.

    2015-01-01

    Background Proton pump inhibitors (PPIs) are commonly used drugs for the treatment of gastric reflux. Recent retrospective cohorts and large database studies have raised concern that the use of PPIs is associated with increased cardiovascular (CV) risk. However, there is no prospective clinical study evaluating whether the use of PPIs directly causes CV harm. Methods We conducted a controlled open-label cross-over pilot study among 21 adults aged 18 and older who are healthy (n = 11) or have established clinical cardiovascular disease (n = 10). Study subjects were assigned to receive a PPI (Prevacid; 30 mg) or a placebo pill once daily for 4 weeks. After a 2 week washout period, participants were crossed-over to receive the alternate treatment for the ensuing 4 weeks. Subjects underwent evaluation of vascular function (by the EndoPAT technique) and had plasma levels of asymmetric dimethylarginine (ADMA, an endogenous inhibitor of endothelial function previously implicated in PPI-mediated risk) measured prior to and after each treatment interval. Results We observed a marginal inverse correlation between the EndoPAT score and plasma levels of ADMA (r = −0.364). Subjects experienced a greater worsening in plasma ADMA levels while on PPI than on placebo, and this trend was more pronounced amongst those subjects with a history of vascular disease. However, these trends did not reach statistical significance, and PPI use was also not associated with an impairment in flow mediated vasodilation during the course of this study. Conclusions In this open-label, cross-over pilot study conducted among healthy subjects and coronary disease patients, PPI use did not significantly influence vascular endothelial function. Larger, long-term and blinded trials are needed to mechanistically explain the correlation between PPI use and adverse clinical outcomes, which has recently been reported in retrospective cohort studies. PMID:25835348

  19. Kv7.2 regulates the function of peripheral sensory neurons

    PubMed Central

    King, Chih H.; Lancaster, Eric; Salomon, Daniela; Peles, Elior; Scherer, Steven S.

    2014-01-01

    The Kv7 (KCNQ) family of voltage-gated K+ channels regulates cellular excitability. The functional role of Kv7.2 has been hampered by the lack of a viable Kcnq2-null animal model. In this study, we generated homozygous Kcnq2-null sensory neurons using the Cre-Lox system; in these mice, Kv7.2 expression is absent in the peripheral sensory neurons, whereas the expression of other molecular components of nodes (including Kv7.3), paranodes, and juxtaparanodes is not altered. The conditional Kcnq2-null animals exhibit normal motor performance, but have increased thermal hyperalgesia and mechanical allodynia. Whole cell patch recording technique demonstrates that Kcnq2-null sensory neurons have increased excitability and reduced spike frequency adaptation. Taken together, our results suggest that the loss of Kv7.2 activity increases the excitability of primary sensory neurons. PMID:24687876

  20. Impaired vascular function after exposure to diesel exhaust generated at urban transient running conditions

    PubMed Central

    2010-01-01

    Background Traffic emissions including diesel engine exhaust are associated with increased respiratory and cardiovascular morbidity and mortality. Controlled human exposure studies have demonstrated impaired vascular function after inhalation of exhaust generated by a diesel engine under idling conditions. Objectives To assess the vascular and fibrinolytic effects of exposure to diesel exhaust generated during urban-cycle running conditions that mimic ambient 'real-world' exposures. Methods In a randomised double-blind crossover study, eighteen healthy male volunteers were exposed to diesel exhaust (approximately 250 μg/m3) or filtered air for one hour during intermittent exercise. Diesel exhaust was generated during the urban part of the standardized European Transient Cycle. Six hours post-exposure, vascular vasomotor and fibrinolytic function was assessed during venous occlusion plethysmography with intra-arterial agonist infusions. Measurements and Main Results Forearm blood flow increased in a dose-dependent manner with both endothelial-dependent (acetylcholine and bradykinin) and endothelial-independent (sodium nitroprusside and verapamil) vasodilators. Diesel exhaust exposure attenuated the vasodilatation to acetylcholine (P < 0.001), bradykinin (P < 0.05), sodium nitroprusside (P < 0.05) and verapamil (P < 0.001). In addition, the net release of tissue plasminogen activator during bradykinin infusion was impaired following diesel exhaust exposure (P < 0.05). Conclusion Exposure to diesel exhaust generated under transient running conditions, as a relevant model of urban air pollution, impairs vasomotor function and endogenous fibrinolysis in a similar way as exposure to diesel exhaust generated at idling. This indicates that adverse vascular effects of diesel exhaust inhalation occur over different running conditions with varying exhaust composition and concentrations as well as physicochemical particle properties. Importantly, exposure to diesel exhaust

  1. Low serum magnesium levels are associated with impaired peripheral nerve function in type 2 diabetic patients.

    PubMed

    Chu, Chen; Zhao, Weijing; Zhang, Yinan; Li, Lu; Lu, Jingyi; Jiang, Lan; Wang, Congrong; Jia, Weiping

    2016-01-01

    The aim of this study was to explore the relationship between serum magnesium and peripheral nerve function in patients with type 2 diabetes (T2DM). A total of 978 T2DM patients were included in the study. Patients were divided into tertiles according to serum magnesium concentration (low tertile: ≤0.85 mmol/L; medium tertile: 0.85 to 0.92 mmol/L; and high tertile: >0.92 mmol/L). All participants underwent nerve conduction (NC) studies. Composite z scores of conduction velocity, latency, and amplitude were constructed, respectively. The serum magnesium levels were significantly lower in patients with abnormal NC than in those with normal NC (0.87 [0.82, 0.92] vs. 0.88 [0.83, 0.93] mmol/L, P = 0.048). The composite z score of amplitude significantly increased with increasing tertiles of magnesium (-0.60 ± 0.02 vs. -0.57 ± 0.02 vs. -0.48 ± 0.03, P for trend = 0.001). After adjusting for all potential confounders, lower serum magnesium levels were still associated with lower composite z score of amplitude (β = 0.095, P = 0.014). In patients with T2DM, lower serum magnesium levels were significantly associated with lower composite z score of amplitude, indicating magnesium might affect peripheral nerve function through axonal degeneration. PMID:27601013

  2. Low serum magnesium levels are associated with impaired peripheral nerve function in type 2 diabetic patients

    PubMed Central

    Chu, Chen; Zhao, Weijing; Zhang, Yinan; Li, Lu; Lu, Jingyi; Jiang, Lan; Wang, Congrong; Jia, Weiping

    2016-01-01

    The aim of this study was to explore the relationship between serum magnesium and peripheral nerve function in patients with type 2 diabetes (T2DM). A total of 978 T2DM patients were included in the study. Patients were divided into tertiles according to serum magnesium concentration (low tertile: ≤0.85 mmol/L; medium tertile: 0.85 to 0.92 mmol/L; and high tertile: >0.92 mmol/L). All participants underwent nerve conduction (NC) studies. Composite z scores of conduction velocity, latency, and amplitude were constructed, respectively. The serum magnesium levels were significantly lower in patients with abnormal NC than in those with normal NC (0.87 [0.82, 0.92] vs. 0.88 [0.83, 0.93] mmol/L, P = 0.048). The composite z score of amplitude significantly increased with increasing tertiles of magnesium (−0.60 ± 0.02 vs. −0.57 ± 0.02 vs. −0.48 ± 0.03, P for trend = 0.001). After adjusting for all potential confounders, lower serum magnesium levels were still associated with lower composite z score of amplitude (β = 0.095, P = 0.014). In patients with T2DM, lower serum magnesium levels were significantly associated with lower composite z score of amplitude, indicating magnesium might affect peripheral nerve function through axonal degeneration. PMID:27601013

  3. Peripheral neutrophil functions and cell signalling in Crohn`s disease.

    PubMed

    Somasundaram, Rajesh; Nuij, Veerle J A A; van der Woude, C Janneke; Kuipers, Ernst J; Peppelenbosch, Maikel P; Fuhler, Gwenny M

    2013-01-01

    The role of the innate immunity in the pathogenesis of Crohn's disease (CD), an inflammatory bowel disease, is a subject of increasing interest. Neutrophils (PMN) are key members of the innate immune system which migrate to sites of bacterial infection and initiate the defence against microbes by producing reactive oxygen species (ROS), before undergoing apoptosis. It is believed that impaired innate immune responses contribute to CD, but it is as yet unclear whether intrinsic defects in PMN signal transduction and corresponding function are present in patients with quiescent disease. We isolated peripheral blood PMN from CD patients in remission and healthy controls (HC), and characterised migration, bacterial uptake and killing, ROS production and cell death signalling. Whereas IL8-induced migration and signalling were normal in CD, trans-epithelial migration was significantly impaired. Uptake and killing of E. coli were normal. However, an increased ROS production was observed in CD PMN after stimulation with the bacterial peptide analogue fMLP, which was mirrored by an increased fMLP-triggered ERK and AKT signal activation. Interestingly, cleavage of caspase-3 and caspase-8 during GMCSF-induced rescue from cell-death was decreased in CD neutrophils, but a reduced survival signal emanating from STAT3 and AKT pathways was concomitantly observed, resulting in a similar percentage of end stage apoptotic PMN in CD patients and HC. In toto, these data show a disturbed signal transduction activation and functionality in peripheral blood PMN from patients with quiescent CD, which point toward an intrinsic defect in innate immunity in these patients. PMID:24367671

  4. Nogo-B regulates endothelial sphingolipid homeostasis to control vascular function and blood pressure.

    PubMed

    Cantalupo, Anna; Zhang, Yi; Kothiya, Milankumar; Galvani, Sylvain; Obinata, Hideru; Bucci, Mariarosaria; Giordano, Frank J; Jiang, Xian-Cheng; Hla, Timothy; Di Lorenzo, Annarita

    2015-09-01

    Endothelial dysfunction is a critical factor in many cardiovascular diseases, including hypertension. Although lipid signaling has been implicated in endothelial dysfunction and cardiovascular disease, specific molecular mechanisms are poorly understood. Here we report that Nogo-B, a membrane protein of the endoplasmic reticulum, regulates endothelial sphingolipid biosynthesis with direct effects on vascular function and blood pressure. Nogo-B inhibits serine palmitoyltransferase, the rate-limiting enzyme of the de novo sphingolipid biosynthetic pathway, thereby controlling production of endothelial sphingosine 1-phosphate and autocrine, G protein-coupled receptor-dependent signaling by this metabolite. Mice lacking Nogo-B either systemically or specifically in endothelial cells are hypotensive, resistant to angiotensin II-induced hypertension and have preserved endothelial function and nitric oxide release. In mice that lack Nogo-B, pharmacological inhibition of serine palmitoyltransferase with myriocin reinstates endothelial dysfunction and angiotensin II-induced hypertension. Our study identifies Nogo-B as a key inhibitor of local sphingolipid synthesis and shows that autocrine sphingolipid signaling within the endothelium is critical for vascular function and blood pressure homeostasis. PMID:26301690

  5. Nogo-B regulates endothelial sphingolipid homeostasis to control vascular function and blood pressure

    PubMed Central

    Kothiya, Milankumar; Galvani, Sylvain; Obinata, Hideru; Bucci, Mariarosaria; Giordano, Frank J; Jiang, Xian-Cheng; Hla, Timothy; Di Lorenzo, Annarita

    2015-01-01

    Endothelial dysfunction is a critical factor in many cardiovascular diseases, including hypertension. Although lipid signaling has been implicated in endothelial dysfunction and cardiovascular disease, specific molecular mechanisms are poorly understood. Here we report that Nogo-B, a membrane protein of the endoplasmic reticulum, regulates endothelial sphingolipid biosynthesis with direct effects on vascular function and blood pressure. Nogo-B inhibits serine palmitoyltransferase, the rate-limiting enzyme of the de novo sphingolipid biosynthetic pathway, thereby controlling production of endothelial sphingosine 1-phosphate and autocrine, G protein–coupled receptor–dependent signaling by this metabolite. Mice lacking Nogo-B either systemically or specifically in endothelial cells are hypotensive, resistant to angiotensin II–induced hypertension and have preserved endothelial function and nitric oxide release. In mice that lack Nogo-B, pharmacological inhibition of serine palmitoyltransferase with myriocin reinstates endothelial dysfunction and angiotensin II–induced hypertension. Our study identifies Nogo-B as a key inhibitor of local sphingolipid synthesis and shows that autocrine sphingolipid signaling within the endothelium is critical for vascular function and blood pressure homeostasis. PMID:26301690

  6. Regulator of G Protein Signaling 2: A Versatile Regulator of Vascular Function

    PubMed Central

    Osei-Owusu, Patrick; Blumer, Kendall J.

    2016-01-01

    Regulators of G protein signaling (RGS) proteins of the B/R4 family are widely expressed in the cardiovascular system where their role in fine tuning G protein signaling is critical to maintaining homeostasis. Among members of this family, RGS2 and RGS5 have been shown to play key roles in cardiac and smooth muscle function by tightly regulating signaling pathways that are activated through Gq/11 and Gi/o classes of heterotrimeric G proteins. This chapter reviews accumulating evidence supporting a key role for RGS2 in vascular function and the implication of changes in RGS2 function and/or expression in the pathogenesis of blood pressure disorders, particularly hypertension. With such understanding, RGS2 and the signaling pathways it controls may emerge as novel targets for developing next-generation anti-hypertensive drugs/agents. PMID:26123303

  7. Enzyme-functionalized vascular grafts catalyze in-situ release of nitric oxide from exogenous NO prodrug.

    PubMed

    Wang, Zhihong; Lu, Yaxin; Qin, Kang; Wu, Yifan; Tian, Yingping; Wang, Jianing; Zhang, Jimin; Hou, Jingli; Cui, Yun; Wang, Kai; Shen, Jie; Xu, Qingbo; Kong, Deling; Zhao, Qiang

    2015-07-28

    Nitric oxide (NO) is an important signaling molecule in cardiovascular system, and the sustained release of NO by endothelial cells plays a vital role in maintaining patency and homeostasis. In contrast, lack of endogenous NO in artificial blood vessel is believed to be the main cause of thrombus formation. In this study, enzyme prodrug therapy (EPT) technique was employed to construct a functional vascular graft by immobilization of galactosidase on the graft surface. The enzyme-functionalized grafts exhibited excellent catalytic property in decomposition of the exogenously administrated NO prodrug. Localized and on-demand release of NO was demonstrated by in vitro release assay and fluorescent probe tracing in an ex vivo model. The immobilized enzyme retained catalytic property even after subcutaneous implantation of the grafts for one month. The functional vascular grafts were implanted into the rat abdominal aorta with a 1-month monitoring period. Results showed effective inhibition of thrombus formation in vivo and enhancement of vascular tissue regeneration and remodeling on the grafts. Thus, we create an enzyme-functionalized vascular graft that can catalyze prodrug to release NO locally and sustainably, indicating that this approach may be useful to develop new cell-free vascular grafts for treatment of vascular diseases. PMID:26004323

  8. Widespread Decreased Expression of Immune Function Genes in Human Peripheral Blood Following Radiation Exposure

    PubMed Central

    Paul, Sunirmal; Smilenov, Lubomir B.; Amundson, Sally A.

    2014-01-01

    We report a large-scale reduced expression of genes in pathways related to cell-type specific immunity functions that emerges from microarray analysis 48 h after ex vivo γ-ray irradiation (0, 0.5, 2, 5, 8 Gy) of human peripheral blood from five donors. This response is similar to that seen in patients at 24 h after the start of total-body irradiation and strengthens the rationale for the ex vivo model as an adjunct to human in vivo studies. The most marked response was in genes associated with natural killer (NK) cell immune functions, reflecting a relative loss of NK cells from the population. T- and B-cell mediated immunity genes were also significantly represented in the radiation response. Combined with our previous studies, a single gene expression signature was able to predict radiation dose range with 97% accuracy at times from 6–48 h after exposure. Gene expression signatures that may report on the loss or functional deactivation of blood cell subpopulations after radiation exposure may be particularly useful both for triage biodosimetry and for monitoring the effect of radiation mitigating treatments. PMID:24168352

  9. Flow cytometric probing of mitochondrial function in equine peripheral blood mononuclear cells

    PubMed Central

    Cassart, Dominique; Fett, Thomas; Sarlet, Michaël; Baise, Etienne; Coignoul, Freddy; Desmecht, Daniel

    2007-01-01

    Background The morphopathological picture of a subset of equine myopathies is compatible with a primary mitochondrial disease, but functional confirmation in vivo is still pending. The cationic dye JC-1 exhibits potential-dependent accumulation in mitochondria that is detectable by a fluorescence shift from green to orange. As a consequence, mitochondrial membrane potential can be optically measured by the orange/green fluorescence intensity ratio. A flow cytometric standardized analytic procedure of the mitochondrial function of equine peripheral blood mononuclear cells is proposed along with a critical appraisal of the crucial questions of technical aspects, reproducibility, effect of time elapsed between blood sampling and laboratory processing and reference values. Results The JC-1-associated fluorescence orange and green values and their ratio were proved to be stable over time, independent of age and sex and hypersensitive to intoxication with a mitochondrial potential dissipator. Unless time elapsed between blood sampling and laboratory processing does not exceed 5 hours, the values retrieved remain stable. Reference values for clinically normal horses are given. Conclusion Whenever a quantitative measurement of mitochondrial function in a horse is desired, blood samples should be taken in sodium citrate tubes and kept at room temperature for a maximum of 5 hours before the laboratory procedure detailed here is started. The hope is that this new test may help in confirming, studying and preventing equine myopathies that are currently imputed to mitochondrial dysfunction. PMID:17903245

  10. Aberrant Functional Connectivity and Structural Atrophy in Subcortical Vascular Cognitive Impairment: Relationship with Cognitive Impairments

    PubMed Central

    Zhou, Xia; Hu, Xiaopeng; Zhang, Chao; Wang, Haibao; Zhu, Xiaoqun; Xu, Liyan; Sun, Zhongwu; Yu, Yongqiang

    2016-01-01

    Abnormal structures in the cortical and subcortical regions have been identified in subcortical vascular cognition impairment (SVCI). However, little is known about the functional alterations in SVCI, and no study refers to the functional connectivity in the prefrontal and subcortical regions in this context. The medial prefrontal cortex (MPFC) is an important region of the executive network and default mode network, and the subcortical thalamus plays vital roles in mediating or modulating these two networks. To investigate both thalamus- and MPFC-related functional connectivity as well as its relationship with cognition in SVCI, 32 SVCI patients and 23 control individuals were administered neuropsychological assessments. They also underwent structural and functional magnetic resonance imaging scans. Voxel-based morphometry and functional connectivity analysis were performed to detect gray matter (GM) atrophy and to characterize the functional alterations in the thalamus and the MPFC. For structural data, we observed that GM atrophy was distributed in both cortical regions and subcortical areas. For functional data, we observed that the thalamus functional connectivity in SVCI was significantly decreased in several cortical regions [i.e., the orbitofrontal lobe (OFL)], which are mainly involved in executive function and memory function. However, connectivity was increased in several frontal regions (i.e., the inferior frontal gyrus), which may be induced by the compensatory recruitment of the decreased functional connectivity. The MPFC functional connectivity was also decreased in executive- and memory-related regions (i.e., the anterior cingulate cortex) along with a motor region (i.e., the supplementary motor area). In addition, the cognitive performance was closely correlated with functional connectivity between the left thalamus and the left OFL in SVCI. The present study, thus, provides evidence for an association between structural and functional alterations

  11. Peripheral ammonia and blood brain barrier structure and function after methamphetamine.

    PubMed

    Northrop, Nicole A; Halpin, Laura E; Yamamoto, Bryan K

    2016-08-01

    An effect of the widely abuse psychostimulant, methamphetamine (Meth), is blood-brain-barrier (BBB) disruption; however, the mechanism by which Meth causes BBB disruption remains unclear. Recently it has been shown that Meth produces liver damage and consequent increases in plasma ammonia. Ammonia can mediate oxidative stress and inflammation, both of which are known to cause BBB disruption. Therefore, the current studies examined the role of peripheral ammonia in Meth-induced disruption of BBB structure and function. A neurotoxic Meth regimen (10 mg/kg, ip, q 2 h, ×4) administered to rats increased plasma ammonia and active MMP-9 in the cortex 2 h after the last Meth injection, compared to saline treated rats. At 24 h after Meth treatment, decreased immunoreactivity of BBB structural proteins, occludin and claudin-5, and increased extravasation of 10,000 Da FITC-dextran were observed, as compared to saline controls. Pretreatment with lactulose (5.3 g/kg, po, q 12 h), a drug that remains in the lumen of the intestine and promotes ammonia excretion, prevented the Meth-induced increases in plasma ammonia. These results were paralleled by the prevention of decreases in BBB structural proteins, increases in extravasation of 10,000 Da FITC-dextran and increases in active MMP-9. The results indicate that Meth-induced increases in ammonia produce BBB disruption and suggest that MMP-9 activation mediates the BBB disruption. These findings identify a novel mechanism of Meth-induced BBB disruption that is mediated by plasma ammonia and are the first to identify a peripheral contribution to Meth-induced BBB disruption. PMID:26972828

  12. Endothelial PECAM-1 and its function in vascular physiology and atherogenic pathology.

    PubMed

    Chistiakov, Dimitry A; Orekhov, Alexander N; Bobryshev, Yuri V

    2016-06-01

    Platelet endothelial cell adhesion molecule (PECAM-1) is highly expressed in vascular cells such as endothelial cells (ECs) and blood-borne cells like platelets and leukocytes. In ECs, this molecule controls junctional and adhesive properties. In physiological conditions, PECAM-1 supports the endothelial barrier function. In inflammation that is observed in vessels affected by atherosclerosis, the function of PECAM-1 is impaired, an event that leads to increased adhesion of neutrophils and other leukocytes to ECs, decreased vascular integrity, and higher leukocyte transmigration to the intima media. PECAM-1 has six extracellular immunoglobulin (Ig)-like domains that support attraction and adhesion of leukocytes to ECs. The cytoplasmic tail of PECAM-1 contains two tyrosine residues (Tyr-663 and Tyr-686) that could be phosphorylated by Src family protein kinases is involved in the intracellular signaling. Actually, those tyrosines are the part of the immunoreceptor tyrosine-based inhibition motifs (ITIMs) that inhibit inflammation. However, in atherosclerosis, the PECAM-1-dependent immune suppression is disturbed. This in turn facilitates recruitment of leukocytes and supports proatherogenic inflammation. PMID:27079772

  13. Immortalized Functional Endothelial Progenitor Cell Lines from Umbilical Cord Blood for Vascular Tissue Engineering

    PubMed Central

    Sobhan, Praveen K.; Seervi, Mahendra; Joseph, Jeena; Varghese, Saneesh; Pillai, Prakash Rajappan; Sivaraman, Divya Mundackal; James, Jackson; George, Roshin Elizabeth; Elizabeth, K.E.; Pillai, M. Radhakrishna

    2012-01-01

    Endothelial progenitor cells (EPCs) play a significant role in multiple biological processes such as vascular homeostasis, regeneration, and tumor angiogenesis. This makes them a promising cell of choice for studying a variety of biological processes, toxicity assays, biomaterial–cell interaction studies, as well as in tissue-engineering applications. In this study, we report the generation of two clones of SV40-immortalized EPCs from umbilical cord blood. These cells retained most of the functional features of mature endothelial cells and showed no indication of senescence after repeated culture for more than 240 days. Extensive functional characterization of the immortalized cells by western blot, flow cytometry, and immunofluorescence studies substantiated that these cells retained their ability to synthesize nitric oxide, von Willebrand factor, P-Selectin etc. These cells achieved unlimited proliferation potential subsequent to inactivation of the cyclin-dependent kinase inhibitor p21, but failed to form colonies on soft agar. We also show their enhanced growth and survival on vascular biomaterials compared to parental cultures in late population doubling. These immortalized EPCs can be used as a cellular model system for studying the biology of these cells, gene manipulation experiments, cell–biomaterial interactions, as well as a variety of tissue-engineering applications. PMID:22889128

  14. The Restorative Effects of Eucommia ulmoides Oliver Leaf Extract on Vascular Function in Spontaneously Hypertensive Rats.

    PubMed

    Hosoo, Shingo; Koyama, Masahiro; Kato, Mai; Hirata, Tetsuya; Yamaguchi, Yasuyo; Yamasaki, Hiroo; Wada, Atsunori; Wada, Keiji; Nishibe, Sansei; Nakamura, Kozo

    2015-01-01

    Eucommia ulmoides Oliv. leaf is a traditional Chinese antihypertensive and antidiabetic medicine. We examined the effects of chronic Eucommia leaf extract (ELE) administration on artery function and morphology in spontaneously hypertensive rats (SHRs). ELE was orally administered via normal diet ad libitum to six-week-old male SHRs at a concentration of 5% for seven weeks. Acetylcholine (ACh)-induced endothelium-dependent relaxation, sodium nitroprusside (SNP)-induced endothelium-independent relaxation, plasma nitric oxide (NO) levels, and media thickness were assessed. ELE significantly improved ACh-induced aortic endothelium-dependent relaxation but did not affect SNP-induced endothelium-independent relaxation in the SHRs, as compared to the animals receiving normal diet. Plasma NO levels and media thickness were significantly increased and decreased, respectively, in the ELE-treated SHRs. Therefore, long-term ELE administration may effectively improve vascular function by increasing plasma NO levels and bioavailability, and by preventing vascular hypertrophy in the SHR aorta. PMID:26690110

  15. Omega-3 Polyunsaturated Fatty Acids: Structural and Functional Effects on the Vascular Wall

    PubMed Central

    Zanetti, Michela; Grillo, Andrea; Losurdo, Pasquale; Panizon, Emiliano; Mearelli, Filippo; Cattin, Luigi; Barazzoni, Rocco; Carretta, Renzo

    2015-01-01

    Omega-3 polyunsaturated fatty acids (n-3 PUFA) consumption is associated with reduced cardiovascular disease risk. Increasing evidence demonstrating a beneficial effect of n-3 PUFA on arterial wall properties is progressively emerging. We reviewed the recent available evidence for the cardiovascular effects of n-3 PUFA focusing on structural and functional properties of the vascular wall. In experimental studies and clinical trials n-3 PUFA have shown the ability to improve arterial hemodynamics by reducing arterial stiffness, thus explaining some of its cardioprotective properties. Recent studies suggest beneficial effects of n-3 PUFA on endothelial activation, which are likely to improve vascular function. Several molecular, cellular, and physiological pathways influenced by n-3 PUFA can affect arterial wall properties and therefore interfere with the atherosclerotic process. Although the relative weight of different physiological and molecular mechanisms and the dose-response on arterial wall properties have yet to be determined, n-3 PUFA have the potential to beneficially impact arterial wall remodeling and cardiovascular outcomes by targeting arterial wall stiffening and endothelial dysfunction. PMID:26301252

  16. Exercise training improves vascular function in adolescents with type 2 diabetes.

    PubMed

    Naylor, Louise H; Davis, Elizabeth A; Kalic, Rachelle J; Paramalingam, Niru; Abraham, Mary B; Jones, Timothy W; Green, Daniel J

    2016-02-01

    The impact of exercise training on vascular health in adolescents with type 2 diabetes has not been previously studied. We hypothesized that exercise training would improve micro- and macrovascular health in adolescents with type 2 diabetes. Thirteen adolescents (13-21 years, 10F) with type 2 diabetes were recruited from Princess Margaret Hospital. Participants were randomized to receive either an exercise program along with standard clinical care (n = 8) or standard care alone (n = 5). Those in the intervention group received 12 weeks of gym-based, personalized, and supervised exercise training. Those in the control group were instructed to maintain usual activity levels. Assessments were conducted at baseline and following week 12. The exercise group was also studied 12 weeks following the conclusion of their program. Assessments consisted of conduit artery endothelial function (flow-mediated dilation, FMD) and microvascular function (cutaneous laser Doppler). Secondary outcomes included body composition (dual-energy X-ray absorptiometry, DXA), glycemic control (whole body insulin sensitivity, M) assessed using the euglycemic-hyperinsulinemic clamp protocol, cardiorespiratory fitness (V˙O2peak), and muscular strength (1RM). Exercise training increased FMD (P < 0.05), microvascular function (P < 0.05), total lean mass (P < 0.05), and muscle strength (P < 0.001). There were no changes in cardiorespiratory fitness, body weight, BMI, or M. In the control group, body weight (P < 0.01), BMI (P < 0.01), and total fat mass (P < 0.05) increased. At week 24, improvements in vascular function were reversed. This study indicates that exercise training can improve both conduit and microvascular endothelial function and health, independent of changes in insulin sensitivity in adolescents with type 2 diabetes. PMID:26887327

  17. Omega-6 and omega-3 fatty acids predict accelerated decline of peripheral nerve function in older persons

    PubMed Central

    Lauretani, F.; Bandinelli, S.; Benedetta, B.; Cherubini, A.; Iorio, A. D.; Blè, A.; Giacomini, V.; Corsi, A. M.; Guralnik, J. M.; Ferrucci, L.

    2009-01-01

    Pre-clinical studies suggest that both omega-6 and omega-3 fatty acids have beneficial effects on peripheral nerve function. Rats feed a diet rich in polyunsaturated fatty acids (PUFAs) showed modification of phospholipid fatty acid composition in nerve membranes and improvement of sciatic nerve conduction velocity (NCV). We tested the hypothesis that baseline plasma omega-6 and omega-3 fatty acids levels predict accelerated decline of peripheral nerve function. Changes between baseline and the 3-year follow-up in peripheral nerve function was assessed by standard surface ENG of the right peroneal nerve in 384 male and 443 female participants of the InCHIANTI study (age range: 24–97 years). Plasma concentrations of selected fatty acids assessed at baseline by gas chromatography. Independent of confounders, plasma omega-6 fatty acids and linoleic acid were significantly correlated with peroneal NCV at enrollment. Lower plasma PUFA, omega-6 fatty acids, linoleic acid, ratio omega-6/omega-3, arachidonic acid and docosahexanoic acid levels were significantly predicted a steeper decline in nerve function parameters over the 3-year follow-up. Low plasma omega-6 and omega-3 fatty acids levels were associated with accelerated decline of peripheral nerve function with aging. PMID:17594339

  18. Omega-6 and omega-3 fatty acids predict accelerated decline of peripheral nerve function in older persons.

    PubMed

    Lauretani, F; Bandinelli, S; Bartali, B; Benedetta, B; Cherubini, A; Iorio, A D; Blè, A; Giacomini, V; Corsi, A M; Guralnik, J M; Ferrucci, L

    2007-07-01

    Pre-clinical studies suggest that both omega-6 and omega-3 fatty acids have beneficial effects on peripheral nerve function. Rats feed a diet rich in polyunsaturated fatty acids (PUFAs) showed modification of phospholipid fatty acid composition in nerve membranes and improvement of sciatic nerve conduction velocity (NCV). We tested the hypothesis that baseline plasma omega-6 and omega-3 fatty acids levels predict accelerated decline of peripheral nerve function. Changes between baseline and the 3-year follow-up in peripheral nerve function was assessed by standard surface ENG of the right peroneal nerve in 384 male and 443 female participants of the InCHIANTI study (age range: 24-97 years). Plasma concentrations of selected fatty acids assessed at baseline by gas chromatography. Independent of confounders, plasma omega-6 fatty acids and linoleic acid were significantly correlated with peroneal NCV at enrollment. Lower plasma PUFA, omega-6 fatty acids, linoleic acid, ratio omega-6/omega-3, arachidonic acid and docosahexanoic acid levels were significantly predicted a steeper decline in nerve function parameters over the 3-year follow-up. Low plasma omega-6 and omega-3 fatty acids levels were associated with accelerated decline of peripheral nerve function with aging. PMID:17594339

  19. Peripheral Neuropathy

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS NINDS Peripheral Neuropathy Information Page Condensed from Peripheral Neuropathy Fact Sheet ... Español Additional resources from MedlinePlus What is Peripheral Neuropathy? Peripheral neuropathy describes damage to the peripheral nervous ...

  20. Bilayered vascular graft derived from human induced pluripotent stem cells with biomimetic structure and function

    PubMed Central

    Nakayama, Karina H; Joshi, Prajakta A; Lai, Edwina S; Gujar, Prachi; Joubert, Lydia-M; Chen, Bertha; Huang, Ngan F

    2015-01-01

    Background: We developed an aligned bi-layered vascular graft derived from human induced pluripotent stem cells (iPSCs) that recapitulates the cellular composition, orientation, and anti-inflammatory function of blood vessels. Materials & methods: The luminal layer consisted of longitudinal-aligned nanofibrillar collagen containing primary endothelial cells (ECs) or iPSC-derived ECs (iPSC-ECs). The outer layer contained circumferentially oriented nanofibrillar collagen with primary smooth muscle cells (SMCs) or iPSC-derived SMCs(iPSC-SMCs). Results: On the aligned scaffolds, cells organized F-actin assembly within 8º from the direction of nanofibrils. When compared to randomly-oriented scaffolds, EC-seeded aligned scaffolds had significant reduced inflammatory response, based on adhesivity to monocytes. Conclusion: This study highlights the importance of anisotropic scaffolds in directing cell form and function, and has therapeutic significance as physiologically relevant blood vessels. PMID:26440211

  1. Improved Glycemic Control and Vascular Function in Overweight and Obese Subjects by Glyoxalase 1 Inducer Formulation.

    PubMed

    Xue, Mingzhan; Weickert, Martin O; Qureshi, Sheharyar; Kandala, Ngianga-Bakwin; Anwar, Attia; Waldron, Molly; Shafie, Alaa; Messenger, David; Fowler, Mark; Jenkins, Gail; Rabbani, Naila; Thornalley, Paul J

    2016-08-01

    Risk of insulin resistance, impaired glycemic control, and cardiovascular disease is excessive in overweight and obese populations. We hypothesized that increasing expression of glyoxalase 1 (Glo1)-an enzyme that catalyzes the metabolism of reactive metabolite and glycating agent methylglyoxal-may improve metabolic and vascular health. Dietary bioactive compounds were screened for Glo1 inducer activity in a functional reporter assay, hits were confirmed in cell culture, and an optimized Glo1 inducer formulation was evaluated in a randomized, placebo-controlled crossover clinical trial in 29 overweight and obese subjects. We found trans-resveratrol (tRES) and hesperetin (HESP), at concentrations achieved clinically, synergized to increase Glo1 expression. In highly overweight subjects (BMI >27.5 kg/m(2)), tRES-HESP coformulation increased expression and activity of Glo1 (27%, P < 0.05) and decreased plasma methylglyoxal (-37%, P < 0.05) and total body methylglyoxal-protein glycation (-14%, P < 0.01). It decreased fasting and postprandial plasma glucose (-5%, P < 0.01, and -8%, P < 0.03, respectively), increased oral glucose insulin sensitivity index (42 mL ⋅ min(-1) ⋅ m(-2), P < 0.02), and improved arterial dilatation Δbrachial artery flow-mediated dilatation/Δdilation response to glyceryl nitrate (95% CI 0.13-2.11). In all subjects, it decreased vascular inflammation marker soluble intercellular adhesion molecule-1 (-10%, P < 0.01). In previous clinical evaluations, tRES and HESP individually were ineffective. tRES-HESP coformulation could be a suitable treatment for improved metabolic and vascular health in overweight and obese populations. PMID:27207552

  2. Involvement of the peripheral sensory and sympathetic nervous system in the vascular endothelial expression of ICAM-1 and the recruitment of opioid-containing immune cells to inhibit inflammatory pain.

    PubMed

    Mousa, Shaaban A; Shaqura, Mohammed; Brendl, Ute; Al-Khrasani, Mahmoud; Fürst, Susanna; Schäfer, Michael

    2010-11-01

    Endogenous opioids are known to be released within certain brain areas following stressful stimuli. Recently, it was shown that also leukocytes are a potential source of endogenously released opioid peptides following stress. They activate sensory neuron opioid receptors and result in the inhibition of local inflammatory pain. An important prerequisite for the recruitment of such leukocytes is the expression of intracellular adhesion molecule-1 (ICAM-1) in blood vessels of inflamed tissue. Here, we investigated the contribution of peripheral sensory and/or sympathetic nerves to the enhanced expression of ICAM-1 simultaneously with the increased recruitment of opioid peptide-containing leukocytes to promote the inhibition of inflammatory pain. Selective degeneration of either peripheral sensory or sympathetic nerve fibers by their respective neurotoxins, capsaicin or 6-hydroxydopamime, significantly reduced the subcutaneous immigration of β-endorphin- (END-) and met-enkephalin- (ENK-)-containing polymorphonuclear leukocytes (PMN) (in the early phase) and mononuclear cells (in the late phase) during painful Freund's complete adjuvant (FCA) rat hind paw inflammation. In contrast, this treatment did not alter the percentage of opioid peptide-containing leukocytes in the circulation. Calcitonin gene-related peptide- (CGRP-) and tyrosine hydroxylase- (TH-) immunoreactive (IR) nerve fibers were in close contact to ICAM-1 IR blood vessels within inflamed subcutaneous tissue. The selective degeneration of sensory or sympathetic nerve fibers attenuated the enhanced expression of vascular endothelial ICAM-1 after intraplantar (i.pl.) FCA and abolished endogenous opioid peptide-mediated peripheral analgesia. Our results suggest that, during localized inflammatory pain, peripheral sensory and sympathetic nerve fibers augment the expression of vascular endothelial ICAM-1 simultaneously with the increased recruitment of opioid peptide-containing leukocytes which consequently

  3. Disruption of the nonneuronal tph1 gene demonstrates the importance of peripheral serotonin in cardiac function

    PubMed Central

    Côté, Francine; Thévenot, Etienne; Fligny, Cécile; Fromes, Yves; Darmon, Michèle; Ripoche, Marie-Anne; Bayard, Elisa; Hanoun, Naima; Saurini, Françoise; Lechat, Philippe; Dandolo, Luisa; Hamon, Michel; Mallet, Jacques; Vodjdani, Guilan

    2003-01-01

    Serotonin (5-HT) controls a wide range of biological functions. In the brain, its implication as a neurotransmitter and in the control of behavioral traits has been largely documented. At the periphery, its modulatory role in physiological processes, such as the cardiovascular function, is still poorly understood. The rate-limiting enzyme of 5-HT synthesis, tryptophan hydroxylase (TPH), is encoded by two genes, the well characterized tph1 gene and a recently identified tph2 gene. In this article, based on the study of a mutant mouse in which the tph1 gene has been inactivated by replacement with the β-galactosidase gene, we establish that the neuronal tph2 is expressed in neurons of the raphe nuclei and of the myenteric plexus, whereas the nonneuronal tph1, as detected by β-galactosidase expression, is in the pineal gland and the enterochromaffin cells. Anatomic examination of the mutant mice revealed larger heart sizes than in wild-type mice. Histological investigation indicates that the primary structure of the heart muscle is not affected. Hemodynamic analyses demonstrate abnormal cardiac activity, which ultimately leads to heart failure of the mutant animals. This report links loss of tph1 gene expression, and thus of peripheral 5-HT, to a cardiac dysfunction phenotype. The tph1-/- mutant may be valuable for investigating cardiovascular dysfunction observed in heart failure in humans. PMID:14597720

  4. Association of Hypertension With Erectile Function in Chronic Peripheral Arterial Insufficiency Patients

    PubMed Central

    Spessoto, Luis Cesar Fava; Facio, Fernando Nestor; de Arruda, Jose Germano Ferraz; Arruda, Pedro Francisco F.; Gatti, Marcio; Antoniassi, Thiago Silveira; Facio, Maria Fernanda Warick; de Godoy, Jose Maria Pereira

    2016-01-01

    Background Risk factors may influence the improvement or worsening of erectile dysfunction (ED). The aim of the current study was to evaluate the effect of systemic hypertension on ED in patients with peripheral arterial disease. Methods The effect of hypertension on ED was assessed in 125 consecutive patients in a cross-sectional quantitative study. The ages of the patients ranged from 19 to 88 years old (mean: 59.82 ± 10.48 years). The only exclusion criterion was the amputation of one or both legs. The ankle-arm index was assessed and the international index of ED questionnaire was applied to all participants in the study. Results Of the 125 patients, 22 (17.6%) had mild (grade 1), 50 (40.0%) had moderate (grade 2) and 53 (42.4%) had severe (grade 3) ED. Hypertensive patients have more ED, with ED in hypertensive patients being associated to chronic arterial disease. However, in comparison with normotensive patients, hypertension exerts an immediate protective effect on erectile function. Conclusions In conclusion, although erectile function is initially protected by systemic arterial hypertension in patients with chronic arterial disease, both chronic arterial disease and ED deteriorate over the long term in hypertensive patients. PMID:27429678

  5. Quantitative and functional alterations of peripheral blood neutrophils after 10% and 30% thermal injury.

    PubMed

    D'Alesandro, M M; Gruber, D F

    1990-01-01

    Polymorphonuclear leukocytes (PMNs) comprise the majority of early nonspecific inflammatory responses to infection or trauma and, as such, must be of sufficient number and qualitative function to properly limit and combat inflammation. Peripheral PMNs isolated from rats that received 10% or 30% body surface area full-thickness thermal injuries were quantitated and examined for functional alterations in membrane potential and cytosolic hydrogen peroxide production for 35 days after thermal injury. With 10% thermal injury, leukocytes increased quantitatively to experimental maximums that were 70% above normal on day 7 before a return to normal by day 28. Platelet levels showed a nonsignificant decrease for 2 days after thermal injury before increasing to levels 20% to 40% above normal through day 28. Phorbol myristate acetate-induced PMN membrane depolarization was inhibited as much as 30% for 21 days after 10% thermal injury. No changes in oxidative activity were apparent except for day 14, when hydrogen peroxide production was 40% above normal. With 30% thermal injury, leukocyte quantities were three to five times normal, with increased relative numbers of PMNs and decreased lymphocytes through day 28. Platelet levels decreased for 4 days before increasing to levels 30% to 47% above normal through day 21. Compared with 10% thermal injury, 30% thermal injury further reduced the ability of PMN membranes to depolarize through day 35. In addition, PMN hydrogen peroxide production was 30% lower on day 1 and increased thereafter to levels that were 40% above normal on day 21. PMID:2401683

  6. Phenotypic, ultra-structural and functional characterization of bovine peripheral blood dendritic cell subsets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dendritic cells (DC) are multifunctional cells that bridge the gap between innate and adaptive immune systems. In bovine, significant information is lacking on the precise identity and role of peripheral blood DC subsets. In this study, we identify and characterize bovine peripheral blood DC subsets...

  7. Cardiac and Vascular Function in Bedrested Volunteers: Effects of Artificial Gravity Training

    NASA Technical Reports Server (NTRS)

    Meng, M.; Platts, S.; Stenger, M.; Diedrich, A.; Schlegel, T.; Natapoff, A.; Knapp, C.; Evans, J.

    2007-01-01

    Cardiovascular effects of an artificial gravity (AG) countermeasure on deconditioned male volunteers were studied. In two groups of men we measured cardiovascular parameters at rest and in response to 30 minutes of 80 deg. head up tilt (HUT) before, at the end of, and four days following 21 days of 6 deg. head down bed rest (HDBR). One group (N=7) underwent no countermeasure while the other (N=8) received a daily, one hour, dose (2.5 gz at the foot, decreasing to 1.0 gz at the heart) of AG training on the Johnson Space Center short radius centrifuge. Cardiovascular parameters measured included heart rate, blood pressure, stroke volume, cardiac output, peripheral vascular resistance, plasma volume shifts, and vasoactive hormones. Untrained subjects exhibited shorter tilt survival (on average 8 minutes shorter) compared to trained subjects. By the end of bed rest, mean heart rate (MHR) was elevated in both groups (both supine and during tilt). In addition, treated subjects demonstrated lower, tilt-induced, increases in MHR four days following HDBR, indicating a more rapid return to pre bed rest conditions. Results from an index of autonomic balance (percentage of MHR spectral power in the respiratory frequency range) in control of heart rate are consistent with the interpretation that parasympathetic nervous system withdrawal was responsible for both tilt- and bed rest-induced increases in MHR. Our data support our pre-study hypothesis that AG treatment would lessen cardiovascular effects of deconditioning in bed rested men and suggest that AG should be further pursued as a space flight countermeasure.

  8. Very rapid effect of pitavastatin on microvascular function in comparison to rosuvastatin: reactive hyperemia peripheral arterial tonometric study

    PubMed Central

    Kono, Yasushi; Fukuda, Shota; Shimada, Kenei; Nakanishi, Koki; Otsuka, Kenichiro; Kubo, Tomoichiro; Jissho, Satoshi; Taguchi, Haruyuki; Yoshikawa, Junichi; Yoshiyama, Minoru

    2013-01-01

    Background: It has been reported that pitavastatin improves endothelial function faster than other statins. Recently introduced reactive hyperemia peripheral arterial tonometry (RH-PAT) provides objective and quantitative assessment of peripheral microvascular function. Purpose: This study aimed to investigate whether peripheral microvascular function improved 2 hours after pitavastatin in subjects with coronary artery disease (CAD) using RH-PAT, and the results were compared with those of rosuvastatin. Methods: This study included 94 subjects with CAD, assigned to a group given 2 mg of pitavastatin (n = 36), a group given 2.5 mg of rosuvastatin (n = 38), and a control group (n = 20). RH-PAT examinations were performed before and 2 hours after statin administration. Results: The RH-PAT index increased 2 hours after pitavastatin administration from 1.82 ± 0.45 to 2.16 ± 0.62 (P = 0.02), whereas there were no differences in the RH-PAT index in the rosuvastatin group (1.79 ± 0.71 to 1.91 ± 0.53, P = 0.09) and the control group (1.68 ± 0.36 to 1.84 ± 0.58, P = 0.4). No significant changes were observed at 2 hours in serum cholesterol levels in each group. Conclusion: The present study demonstrated that peripheral microvascular function improved 2 hours after a single clinical dose of pitavastatin, but not after rosuvastatin. PMID:23667308

  9. Measurements of vascular function using strain-gauge plethysmography: technical considerations, standardization, and physiological findings.

    PubMed

    Alomari, Mahmoud A; Solomito, Angela; Reyes, Rafael; Khalil, Syed Muaz; Wood, Robert H; Welsch, Michael A

    2004-01-01

    The main purpose of the present study was to examine the relationships between measures of fitness [estimated peak oxygen consumption (V(O2) peak) and handgrip strength] and forearm vascular function in 55 young (22.6 +/- 3.5 yr) adults. In addition, the present study considered methodological and technical aspects regarding the examination of the venous system using mercury in-Silastic strain-gauge plethysmography (MSGP). Forearm venous capacitance and outflow were examined using five different [7, 14, 21, 28, and 35 mmHg < diastolic blood pressure (DBP)] venous occlusion pressures and after a 5- and 10-min period of venous occlusion. A pressure of 7 mmHg < DBP and a period of 10 min venous occlusion produced the greatest (P < 0.05) venous capacitance and outflow, without altering arterial indexes. Reproducibility of forearm arterial and venous indexes were evaluated at rest and after 5 min of upper arm arterial occlusion at 240 mmHg on three different occasions within 10 days with the interclass correlation coefficient ranging from 0.70 and 0.94. Estimated V(O2) peak correlated with postocclusion arterial inflow (r = 0.54, P = 0.012) and resting venous outflow (r = 0.56, P = 0.016). Finally, handgrip strength was associated with venous capacitance (r = 0.57, P = 0.007) and outflow (r = 0.67, P = 0.001). These results indicate that the examination of forearm vascular function using MSGP is reproducible. Moreover, the data show the importance of careful consideration of the selection of venous occlusion pressure and period when implementing these measures in longitudinal trials. Finally, the associations between fitness and venous measures suggest a link between venous function and exercise performance. PMID:14512279

  10. Biomechanical activation of vascular endothelium as a determinant of its functional phenotype

    PubMed Central

    García-Cardeña, Guillermo; Comander, Jason; Anderson, Keith R.; Blackman, Brett R.; Gimbrone, Michael A.

    2001-01-01

    One of the striking features of vascular endothelium, the single-cell-thick lining of the cardiovascular system, is its phenotypic plasticity. Various pathophysiologic factors, such as cytokines, growth factors, hormones, and metabolic products, can modulate its functional phenotype in health and disease. In addition to these humoral stimuli, endothelial cells respond to their biomechanical environment, although the functional implications of this biomechanical paradigm of activation have not been fully explored. Here we describe a high-throughput genomic analysis of modulation of gene expression observed in cultured human endothelial cells exposed to two well defined biomechanical stimuli—a steady laminar shear stress and a turbulent shear stress of equivalent spatial and temporal average intensity. Comparison of the transcriptional activity of 11,397 unique genes revealed distinctive patterns of up- and down-regulation associated with each type of stimulus. Cluster analyses of transcriptional profiling data were coupled with other molecular and cell biological techniques to examine whether these global patterns of biomechanical activation are translated into distinct functional phenotypes. Confocal immunofluorescence microscopy of structural and contractile proteins revealed the formation of a complex apical cytoskeleton in response to laminar shear stress. Cell cycle analysis documented different effects of laminar and turbulent shear stresses on cell proliferation. Thus, endothelial cells have the capacity to discriminate among specific biomechanical forces and to translate these input stimuli into distinctive phenotypes. The demonstration that hemodynamically derived stimuli can be strong modulators of endothelial gene expression has important implications for our understanding of the mechanisms of vascular homeostasis and atherogenesis. PMID:11296290

  11. Evolution of peripheral nerve function in humans: novel insights from motor nerve excitability

    PubMed Central

    Farrar, Michelle A; Park, Susanna B; Lin, Cindy S-Y; Kiernan, Matthew C

    2013-01-01

    While substantial alterations in myelination and axonal growth have been described during maturation, their interactions with the configuration and activity of axonal membrane ion channels to achieve impulse conduction have not been fully elucidated. The present study utilized axonal excitability techniques to compare the changes in nerve function across healthy infants, children, adolescents and adults. Multiple excitability indices (stimulus–response curve, strength–duration time constant, threshold electrotonus, current–threshold relationship and recovery cycle) combined with conventional neurophysiological measures were investigated in 57 subjects (22 males, 35 females; age range 0.46–24 years), stimulating the median motor nerve at the wrist. Maturational changes in conduction velocity were paralleled by significant alterations in multiple excitability parameters, similarly reaching steady values in adolescence. Maturation was accompanied by reductions in threshold (P < 0.005) and rheobase (P= 0.001); depolarizing and hyperpolarizing electrotonus progressively reduced (P < 0.001), or ‘fanned-in’; resting current–threshold slope increased (P < 0.0001); accommodation to depolarizing currents prolonged (P < 0.0001); while greater threshold changes in refractoriness (P= 0.001) and subexcitability (P < 0.01) emerged. Taken together, the present findings suggest that passive membrane conductances and the activity of K+ conductances decrease with formation of the axo-glial junction and myelination. In turn, these functional alterations serve to enhance the efficiency and speed of impulse conduction concurrent with the acquisition of motor skills during childhood, and provide unique insight into the evolution of postnatal human peripheral nerve function. Significantly, these findings bring the dynamics of axonal development to the clinical domain and serve to further illuminate pathophysiological mechanisms that occur during development. PMID:23006483

  12. Collateral vessel number, plaque burden, and functional decline in peripheral artery disease

    PubMed Central

    McDermott, Mary M; Carr, James; Liu, Kiang; Kramer, Christopher M; Yuan, Chun; Tian, Lu; Criqui, Michael H; Guralnik, Jack M; Ferrucci, Luigi; Zhao, Lihui; Xu, Dongxiang; Kibbe, Melina; Berry, Jarett; Carroll, Timothy J

    2015-01-01

    Associations of collateral vessels and lower extremity plaque with functional decline are unknown. Among people with peripheral artery disease (PAD), we determined whether greater superficial femoral artery (SFA) plaque burden combined with fewer lower extremity collateral vessels was associated with faster functional decline, compared to less plaque and/or more numerous collateral vessels. A total of 226 participants with ankle–brachial index (ABI) <1.00 underwent magnetic resonance imaging of lower extremity collateral vessels and cross-sectional imaging of the proximal SFA. Participants were categorized as follows: Group 1 (best), maximum plaque area < median and collateral vessel number ≥6 (median); Group 2, maximum plaque area < median and collateral vessel number <6; Group 3, maximum plaque area > median and collateral vessel number ≥6; Group 4 (worst), maximum plaque area > median and collateral vessel number <6. Functional measures were performed at baseline and annually for 2 years. Analyses adjust for age, sex, race, comorbidities, and other confounders. Annual changes in usual-paced walking velocity were: Group 1, +0.01 m/s; Group 2, −0.02 m/s; Group 3, −0.01 m/s; Group 4, −0.05 m/s (p-trend=0.008). Group 4 had greater decline than Group 1 (p<0.001), Group 2 (p=0.029), and Group 3 (p=0.010). Similar trends were observed for fastest-paced 4-meter walking velocity (p-trend=0.018). Results were not substantially changed when analyses were repeated with additional adjustment for ABI. However, there were no associations of SFA plaque burden and collateral vessel number with decline in 6-minute walk. In summary, a larger SFA plaque burden combined with fewer collateral vessels is associated with a faster decline in usual and fastest-paced walking velocity in PAD. PMID:25047855

  13. Variability of residual platelet function despite clopidogrel treatment in patients with peripheral arterial occlusive disease.

    PubMed

    Linnemann, Birgit; Schwonberg, Jan; Toennes, Stefan W; Mani, Helen; Lindhoff-Last, Edelgard

    2010-04-01

    Residual platelet function despite treatment with clopidogrel may predict an unfavourable cardiovascular outcome. The majority of studies have investigated the effects of clopidogrel administration in conjunction with aspirin in patients undergoing percutaneous coronary intervention. The primary objective of the present study was to assess the platelet response to clopidogrel in the absence of aspirin in patients with peripheral arterial occlusive disease (PAOD) and to investigate whether non-responsiveness to clopidogrel is reproducible during long-term follow-up. Fifty-four clinically stable PAOD patients on a maintenance dose of 75 mg/d clopidogrel were enrolled in this study. Platelet function was assessed at baseline and after a median follow-up of 18 months using light transmittance aggregometry (LTA) with 2 microM ADP as an agonist. HPLC-coupled mass spectrometry was used to detect clopidogrel and clopidogrel carboxylic acid, the main metabolite of clopidogrel. Residual platelet function, as defined by late aggregation values within the reference range (i.e., >43%), was observed in 35.2% of patients at baseline and 17.6% during follow-up. During the observation period, 26.5% had switched from responder to non-responder status or vice versa. Among non-responders, either clopidogrel or its metabolite was detected in 89.5% and 83.3% of patients at baseline and at follow-up, respectively. We conclude that non-responsiveness to clopidogrel as determined by ADP-induced LTA is not stable over time. This phenomenon cannot be attributed to non-compliance alone. PMID:20153859

  14. Electrical stimulation accelerates nerve regeneration and functional recovery in delayed peripheral nerve injury in rats.

    PubMed

    Huang, Jinghui; Zhang, Yongguang; Lu, Lei; Hu, Xueyu; Luo, Zhuojing

    2013-12-01

    The present study aims to investigate the potential of brief electrical stimulation (ES; 3 V, 20 Hz, 20 min) in improving functional recovery in delayed nerve injury repair (DNIR). The sciatic nerve of Sprague Dawley rats was transected, and the repair of nerve injury was delayed for different time durations (2, 4, 12 and 24 weeks). Brief depolarizing ES was applied to the proximal nerve stump when the transected nerve stumps were bridged with a hollow nerve conduit (5 mm in length) after delayed periods. We found that the diameter and number of regenerated axons, the thickness of myelin sheath, as well as the number of Fluoro-Gold retrograde-labeled motoneurons and sensory neurons were significantly increased by ES, suggesting that brief ES to proximal nerve stumps is capable of promoting nerve regeneration in DNIR with different delayed durations, with the longest duration of 24 weeks. In addition, the amplitude of compound muscle action potential (gastrocnemius muscle) and nerve conduction velocity were also enhanced, and gastrocnemius muscle atrophy was partially reversed by brief ES, indicating that brief ES to proximal nerve stump was able to improve functional recovery in DNIR. Furthermore, brief ES was capable of increasing brain-derived neurotrophic factor (BDNF) expression in the spinal cord in DNIR, suggesting that BDNF-mediated neurotrophin signaling might be one of the contributing factors to the beneficial effect of brief ES on DNIR. In conclusion, the present findings indicate the potential of using brief ES as a useful method to improve functional recovery for delayed repair of peripheral nerve lesions. PMID:24118464

  15. Cortical Brain Mapping of Peripheral Nerves Using Functional Magnetic Resonance Imaging in a Rodent Model

    PubMed Central

    Cho, Younghoon R.; Jones, Seth R.; Pawela, Christopher P.; Li, Rupeng; Kao, Dennis S.; Schulte, Marie L.; Runquist, Matthew L.; Yan, Ji-Geng; Hudetz, Anthony G.; Jaradeh, Safwan S.; Hyde, James S.; Matloub, Hani S.

    2008-01-01

    The regions of the body have cortical and subcortical representation in proportion to their degree of innervation. The rat forepaw has been studied extensively in recent years using functional magnetic resonance imaging (fMRI)—typically by stimulation using electrodes directly inserted into the skin of the forepaw. Here, we stimulate using surgically implanted electrodes. A major distinction is that stimulation of the skin of the forepaw is mostly sensory, whereas direct nerve stimulation reveals not only the sensory system but also deep brain structures associated with motor activity. In this paper, we seek to define both the motor and sensory cortical and subcortical representations associated with the four major nerves of the rodent upper extremity. We electrically stimulated each nerve (median, ulnar, radial, and musculocutaneous) during fMRI acquisition using a 9.4T Bruker scanner. A current level of 0.5-1.0 mA and a frequency of 5 Hz were used while keeping the duration constant. A distinct pattern of cortical activation was found for each nerve that can be correlated with known sensorimotor afferent and efferent pathways to the rat forepaw. This direct nerve stimulation rat model can provide insight into peripheral nerve injury. PMID:18924070

  16. Anchorage and lymphocyte function. Spreading-capacity distinguishes common thymocytes and peripheral T lymphocytes.

    PubMed Central

    Otteskog, P; Sundqvist, K G

    1983-01-01

    Contact of T-enriched human blood lymphocytes with an adhesive surface in the presence of Concanavalin A (Con A) almost immediately induced a sequence of motile changes in virtually all cells. The initial event in this spreading process was the formation of filopodia distinct from the microvilli of lymphocytes in suspension. The filopodia were accompanied by lamellipodia, ruffles and flattening of the nucleus. Contact with a nonadhesive substratum in the presence of Con A did not trigger this sequence of changes. Cytochalasin B and D or low temperature inhibited the contact-induced changes. With the exception of a small number of cells (5-15%), T-enriched lymphocytes that were allowed to settle in the absence of Con A showed a radius of action (area occupied by the cells/translational movement per hr) of 39 micrometers 2/ less than 1 micrometer. The small 'motile' population showed a radius of action of 74 micrometers 2/8 micrometers. The Con-A-mediated spreading-process yielded a radius of action of the lymphocytes of 117 micrometers 2/6 micrometers. This augmented radius of action markedly facilitated cell-cell interaction in a high frequency of the cells and appeared to be a prerequisite for such interactions at 'low' cell density. Thymocytes reactive with OKT 6 antibodies or belonging to the 'high-density' fraction of cells attached to a Con-A-coated surface to the same extent as peripheral OKT 3 positive lymphocytes, but did not exhibit the morphological changes characteristic of a spreading-process. In contrast, OKT 6 negative thymocytes or thymocytes with a relatively low density showed spreading indistinguishable from that of OKT 3 positive peripheral lymphocytes. These results characterize the spreading-process in human T lymphocytes and demonstrate its functional importance for interactions with the environment. Spreading-capacity appears to reflect the stage of maturation of T cells. Images Figure 1 Figure 2 Figure 3 Figure 4b Figure 4c Figure 7 PMID

  17. Functional role of stromal interaction molecule 1 (STIM1) in vascular smooth muscle cells

    SciTech Connect

    Takahashi, Yoichiro; Watanabe, Hiroyuki; Murakami, Manabu; Ono, Kyoichi; Munehisa, Yoshiko; Koyama, Takashi; Nobori, Kiyoshi; Iijima, Toshihiko; Ito, Hiroshi

    2007-10-05

    We investigated the functional role of STIM1, a Ca{sup 2+} sensor in the endoplasmic reticulum (ER) that regulates store-operated Ca{sup 2+} entry (SOCE), in vascular smooth muscle cells (VSMCs). STIM1 was mainly localized at the ER and plasma membrane. The knockdown of STIM1 expression by small interfering (si) RNA drastically decreased SOCE. In contrast, an EF-hand mutant of STIM1, STIM1{sup E87A}, produced a marked increase in SOCE, which was abolished by co-transfection with siRNA to transient receptor potential canonical 1 (TRPC1). In addition, transfection with siRNA against STIM1 suppressed phosphorylation of cAMP-responsive element binding protein (CREB) and cell growth. These results suggest that STIM1 is an essential component of SOCE and that it is involved in VSMC proliferation.

  18. Acute exercise improves endothelial function despite increasing vascular resistance during stress in smokers and nonsmokers.

    PubMed

    Rooks, Cherie R; McCully, Kevin K; Dishman, Rod K

    2011-09-01

    The present study examined the effect of acute exercise on flow mediated dilation (FMD) and reactivity to neurovascular challenges among female smokers and nonsmokers. FMD was determined by arterial diameter, velocity, and blood flow measured by Doppler ultrasonography after forearm occlusion. Those measures and blood pressure and heart rate were also assessed in response to forehead cold and the Stroop Color-Word Conflict Test (CWT) before and after 30 min of rest or an acute bout of cycling exercise (∼50% VO₂ peak). Baseline FMD and stress responses were not different between smokers and nonsmokers. Compared to passive rest, exercise increased FMD and decreased arterial velocity and blood flow responses during the Stroop CWT and forehead cold in both groups. Overall, acute exercise improved endothelial function among smokers and nonsmokers despite increasing vascular resistance and reducing limb blood flow during neurovascular stress. PMID:21457274

  19. The influence of vascularization of transplanted processed allograft nerve on return of motor function in rats.

    PubMed

    Giusti, Guilherme; Lee, Joo-Yup; Kremer, Thomas; Friedrich, Patricia; Bishop, Allen T; Shin, Alexander Y

    2016-02-01

    Processed nerve allografts have become an alternative to repair segmental nerve defects, with results comparable with autografts regarding sensory recovery; however, they have failed to reproduce comparable motor recovery. The purpose of this study was to determine how revascularizaton of processed nerve allograft would affect motor recovery. Eighty-eight rats were divided in four groups of 22 animals each. A unilateral 10-mm sciatic nerve defect was repaired with allograft (group I), allograft wrapped with silicone conduit (group II), allograft augmented with vascular endothelial growth factor (group III), or autograft (group IV). Eight animals from each group were sacrificed at 3 days, and the remaining animals at 16 weeks. Revascularization was evaluated by measuring the graft capillary density at 3 days and 16 weeks. Measurements of ankle contracture, compound muscle action potential, tibialis anterior muscle weight and force, and nerve histomorphometry were performed at 16 weeks. All results were normalized to the contralateral side. The results of capillary density at 3 days were 0.99% ± 1.3% for group I, 0.33% ± 0.6% for group II, 0.05% ± 0.1% for group III, and 75.6% ± 45.7% for group IV. At 16 weeks, the results were 69.9% ± 22.4% for group I, 37.0% ± 16.6% for group II, 84.6% ± 46.6% for group III, and 108.3% ± 46.8% for group IV. The results of muscle force were 47.5% ± 14.4% for group I, 21.7% ± 13.5% for group II, 47.1% ± 7.9% for group III, and 54.4% ± 10.6% for group IV. The use of vascular endothelial growth factor in the fashion used in this study improved neither the nerve allograft short-term revascularization nor the functional motor recovery after 16 weeks. Blocking allograft vascularization from surrounding tissues was detrimental for motor recovery. The processed nerve allografts used in this study showed similar functional motor recovery compared with that of the autograft. PMID

  20. Vascular Endothelial Function and Blood Pressure Regulation in Afferent Autonomic Failure

    PubMed Central

    Jelani, Qurat-ul-ain; Norcliffe-Kaufmann, Lucy; Kaufmann, Horacio

    2015-01-01

    BACKGROUND Familial dysautonomia (FD) is a rare hereditary disease characterized by loss of afferent autonomic neural fiber signaling and consequent profound impairment of arterial baroreflex function and blood pressure regulation. Whether vascular endothelial dysfunction contributes to defective vasomotor control in this form of afferent autonomic failure is not known. METHODS We assessed blood pressure response to orthostatic stress and vascular endothelial function with brachial artery reactivity testing in 34 FD subjects with afferent autonomic failure and 34 healthy control subjects. RESULTS Forty-four percent of the afferent autonomic failure subjects had uncontrolled hypertension at supine rest (median systolic blood pressure = 148mm Hg, interquartile range (IQR) = 144–155mm Hg; median diastolic blood pressure = 83mm Hg, IQR = 78–105mm Hg), and 88% had abnormal response to orthostatic stress (median decrease in systolic blood pressure after upright tilt = 48mm Hg, IQR = 29–61mm Hg). Flow-mediated brachial artery reactivity did not differ in subjects with afferent autonomic failure vs. healthy control subjects (median = 6.00%, IQR = 1.86–11.77%; vs. median = 6.27%, IQR = 4.65–9.34%; P = 0.75). In afferent autonomic failure subjects, brachial artery reactivity was not associated with resting blood pressure or the magnitude of orthostatic hypotension but was decreased in association with reduced glomerular filtration rate (r = 0.62; P < 0.001). CONCLUSIONS Brachial artery reactivity was preserved in subjects with afferent autonomic failure despite the presence of marked blood pressure dysregulation. Comorbid renal dysfunction was associated with reduced brachial artery reactivity. PMID:25128693

  1. Increasing Muscle Mass Improves Vascular Function in Obese (db/db) Mice

    PubMed Central

    Qiu, Shuiqing; Mintz, James D.; Salet, Christina D.; Han, Weihong; Giannis, Athanassios; Chen, Feng; Yu, Yanfang; Su, Yunchao; Fulton, David J.; Stepp, David W.

    2014-01-01

    Background A sedentary lifestyle is an independent risk factor for cardiovascular disease and exercise has been shown to ameliorate this risk. Inactivity is associated with a loss of muscle mass, which is also reversed with isometric exercise training. The relationship between muscle mass and vascular function is poorly defined. The aims of the current study were to determine whether increasing muscle mass by genetic deletion of myostatin, a negative regulator of muscle growth, can influence vascular function in mesenteric arteries from obese db/db mice. Methods and Results Myostatin expression was elevated in skeletal muscle of obese mice and associated with reduced muscle mass (30% to 50%). Myostatin deletion increased muscle mass in lean (40% to 60%) and obese (80% to 115%) mice through increased muscle fiber size (P<0.05). Myostatin deletion decreased adipose tissue in lean mice, but not obese mice. Markers of insulin resistance and glucose tolerance were improved in obese myostatin knockout mice. Obese mice demonstrated an impaired endothelial vasodilation, compared to lean mice. This impairment was improved by superoxide dismutase mimic Tempol. Deletion of myostatin improved endothelial vasodilation in mesenteric arteries in obese, but not in lean, mice. This improvement was blunted by nitric oxide (NO) synthase inhibitor l‐NG‐nitroarginine methyl ester (l‐NAME). Prostacyclin (PGI2)‐ and endothelium‐derived hyperpolarizing factor (EDHF)‐mediated vasodilation were preserved in obese mice and unaffected by myostatin deletion. Reactive oxygen species) was elevated in the mesenteric endothelium of obese mice and down‐regulated by deletion of myostatin in obese mice. Impaired vasodilation in obese mice was improved by NADPH oxidase inhibitor (GKT136901). Treatment with sepiapterin, which increases levels of tetrahydrobiopterin, improved vasodilation in obese mice, an improvement blocked by l‐NAME. Conclusions Increasing muscle mass by genetic

  2. Coffee polyphenol consumption improves postprandial hyperglycemia associated with impaired vascular endothelial function in healthy male adults.

    PubMed

    Jokura, Hiroko; Watanabe, Isamu; Umeda, Mika; Hase, Tadashi; Shimotoyodome, Akira

    2015-10-01

    Epidemiological studies indicate that habitual coffee consumption lowers the risk of diabetes and cardiovascular diseases. Postprandial hyperglycemia is a direct and independent risk factor for cardiovascular diseases. We previously demonstrated that coffee polyphenol ingestion increased secretion of Glucagon-like peptide 1 (GLP-1), which has been shown to exhibit anti-diabetic and cardiovascular effects. We hypothesized coffee polyphenol consumption may improve postprandial hyperglycemia and vascular endothelial function by increasing GLP-1 release and/or reducing oxidative stress. To examine this hypothesis, we conducted a randomized, acute, crossover, intervention study in healthy male adults, measuring blood parameters and flow-mediated dilation (FMD) after ingestion of a meal with or without coffee polyphenol extract (CPE). Nineteen subjects consumed a test meal with either a placebo- or CPE-containing beverage. Blood biomarkers and FMD were measured at fasting and up to 180 minutes postprandially. The CPE beverage led to a significantly lower peak postprandial increase in blood glucose and diacron-reactive oxygen metabolite, and significantly higher postprandial FMD than the placebo beverage. Postprandial blood GLP-1 increase tended to be higher after ingestion of the CPE beverage, compared with placebo. Subclass analysis revealed that the CPE beverage significantly improved postprandial blood GLP-1 response and reduced blood glucose increase in the subjects with a lower insulinogenic index. Correlation analysis showed postprandial FMD was negatively associated with blood glucose increase after ingestion of the CPE beverage. In conclusion, these results suggest that coffee polyphenol consumption improves postprandial hyperglycemia and vascular endothelial function, which is associated with increased GLP-1 secretion and decreased oxidative stress in healthy humans. PMID:26337017

  3. Muscle-derived follistatin-like 1 functions to reduce neointimal formation after vascular injury

    PubMed Central

    Miyabe, Megumi; Ohashi, Koji; Shibata, Rei; Uemura, Yusuke; Ogura, Yasuhiro; Yuasa, Daisuke; Kambara, Takahiro; Kataoka, Yoshiyuki; Yamamoto, Takashi; Matsuo, Kazuhiro; Joki, Yusuke; Enomoto, Takashi; Hayakawa, Satoko; Hiramatsu-Ito, Mizuho; Ito, Masanori; Van Den Hoff, Maurice J.B.; Walsh, Kenneth; Murohara, Toyoaki; Ouchi, Noriyuki

    2014-01-01

    Aims It is well-established that exercise diminishes cardiovascular risk, but whether humoral factors secreted by muscle confer these benefits has not been conclusively shown. We have shown that the secreted protein follistatin-like 1 (Fstl1) has beneficial actions on cardiac and endothelial function. However, the role of muscle-derived Fstl1 in proliferative vascular disease remains largely unknown. Here, we investigated whether muscle-derived Fstl1 modulates vascular remodelling in response to injury. Methods and results The targeted ablation of Fstl1 in muscle led to an increase in neointimal formation following wire-induced arterial injury compared with control mice. Conversely, muscle-specific Fstl1 transgenic (TG) mice displayed a decrease in the neointimal thickening following arterial injury. Muscle-specific Fstl1 ablation and overexpression increased and decreased, respectively, the frequency of BrdU-positive proliferating cells in injured vessels. In cultured human aortic smooth muscle cells (HASMCs), treatment with human FSTL1 protein decreased proliferation and migration induced by stimulation with PDGF-BB. Treatment with FSTL1 enhanced AMPK phosphorylation, and inhibition of AMPK abrogated the inhibitory actions of FSTL1 on HASMC responses to PDGF-BB. The injured arteries of Fstl1-TG mice exhibited an increase in AMPK phosphorylation, and administration of AMPK inhibitor reversed the anti-proliferative actions of Fstl1 on the vessel wall. Conclusion Our findings indicate that muscle-derived Fstl1 attenuates neointimal formation in response to arterial injury by suppressing SMC proliferation through an AMPK-dependent mechanism. Thus, the release of protein factors from muscle, such as Fstl1, may partly explain why the maintenance of muscle function can have a therapeutic effect on the cardiovascular system. PMID:24743592

  4. Peripheral neuropathy

    MedlinePlus

    Peripheral neuritis; Neuropathy - peripheral; Neuritis - peripheral; Nerve disease; Polyneuropathy ... Neuropathy is very common. There are many types and causes. Often, no cause can be found. Some ...

  5. Low-level X-radiation effects on functional vascular changes in Syrian hamster cheek pouch epithelium during hydrocarbon carcinogenesis

    SciTech Connect

    Lurie, A.G.; Coghill, J.E.; Rippey, R.M.

    1985-07-01

    Effects of repeated low-level X radiation on functional microvascular changes in hamster cheek pouch epithelium during and following carcinogenesis by 7,12-dimethylbenz(a)anthracene (DMBA) were studied. Hamsters were treated with either radiation, DMBA, radiation + DMBA, or no treatment. Animals were sacrificed at 3-week intervals from 0 to 39 weeks after treatments began. Pouch vascular volume and permeability changes were studied by fractional distributions of radiotracers and were analyzed by a variety of statistical methods which explored the vascular parameters, treatment types, elapsed time, presence of the carcinogen, and histopathologic changes. All treatments resulted in significant changes in vascular volume with time, while only DMBA treatments alone resulted in significant changes in vascular permeability with time. As in prior studies, there were significant vascular volume differences between DMBA and DMBA + radiation groups of tumor-bearing cheek pouches. Radiation significantly affected DMBA-associated vascular volume and permeability changes during carcinogenesis. Several possible explanations for the relationship of these changes to the enhancement of DMBA carcinogenesis are discussed.

  6. Differential and synergistic effects of mechanical stimulation and growth factor presentation on vascular wall function.

    PubMed

    Liang, Mao-Shih; Koobatian, Maxwell; Lei, Pedro; Swartz, Daniel D; Andreadis, Stelios T

    2013-10-01

    We investigated the hypothesis that immobilizing TGF-β1 within fibrin hydrogels may act in synergy with cyclic mechanical stimulation to enhance the properties of vascular grafts. To this end, we engineered a fusion TGF-β1 protein that can covalently anchor to fibrin during polymerization upon the action of factor XIII. We also developed a 24-well based bioreactor in which vascular constructs can be mechanically stimulated by distending the silastic mandrel in the middle of each well. TGF-β1 was either conjugated to fibrin or supplied in the culture medium and the fibrin-based constructs were cultured statically for a week followed by cyclic distention for another week. The tissues were examined for myogenic differentiation, vascular reactivity, mechanical properties and ECM content. Our results showed that some aspects of vascular function were differentially affected by growth factor presentation vs. pulsatile force application, while others were synergistically enhanced by both. Overall, this two-prong biomimetic approach improved ECM secretion, vascular reactivity and mechanical properties of vascular constructs. These findings may be applied in other tissue engineering applications such as cartilage, tendon or cardiac regeneration where growth factors TGF-β1 and mechano-stimulation play critical roles. PMID:23810080

  7. Loss-of-Function Mutations in ELMO2 Cause Intraosseous Vascular Malformation by Impeding RAC1 Signaling.

    PubMed

    Cetinkaya, Arda; Xiong, Jingwei Rachel; Vargel, İbrahim; Kösemehmetoğlu, Kemal; Canter, Halil İbrahim; Gerdan, Ömer Faruk; Longo, Nicola; Alzahrani, Ahmad; Camps, Mireia Perez; Taskiran, Ekim Zihni; Laupheimer, Simone; Botto, Lorenzo D; Paramalingam, Eeswari; Gormez, Zeliha; Uz, Elif; Yuksel, Bayram; Ruacan, Şevket; Sağıroğlu, Mahmut Şamil; Takahashi, Tokiharu; Reversade, Bruno; Akarsu, Nurten Ayse

    2016-08-01

    Vascular malformations are non-neoplastic expansions of blood vessels that arise due to errors during angiogenesis. They are a heterogeneous group of sporadic or inherited vascular disorders characterized by localized lesions of arteriovenous, capillary, or lymphatic origin. Vascular malformations that occur inside bone tissue are rare. Herein, we report loss-of-function mutations in ELMO2 (which translates extracellular signals into cellular movements) that are causative for autosomal-recessive intraosseous vascular malformation (VMOS) in five different families. Individuals with VMOS suffer from life-threatening progressive expansion of the jaw, craniofacial, and other intramembranous bones caused by malformed blood vessels that lack a mature vascular smooth muscle layer. Analysis of primary fibroblasts from an affected individual showed that absence of ELMO2 correlated with a significant downregulation of binding partner DOCK1, resulting in deficient RAC1-dependent cell migration. Unexpectedly, elmo2-knockout zebrafish appeared phenotypically normal, suggesting that there might be human-specific ELMO2 requirements in bone vasculature homeostasis or genetic compensation by related genes. Comparative phylogenetic analysis indicated that elmo2 originated upon the appearance of intramembranous bones and the jaw in ancestral vertebrates, implying that elmo2 might have been involved in the evolution of these novel traits. The present findings highlight the necessity of ELMO2 for maintaining vascular integrity, specifically in intramembranous bones. PMID:27476657

  8. Study of the functional state of peripheral vessels in fingers of rheumatological patients by means of laser Doppler flowmetry and cutaneous thermometry measurements

    NASA Astrophysics Data System (ADS)

    Zherebtsova, Angelina I.; Zherebtsov, Evgeny A.; Dunaev, Andrey V.; Podmasteryev, Konstantin V.; Pilipenko, Olga V.; Krupatkin, Alexander I.; Khakhicheva, Lyudmila S.; Muradyan, Vadim F.

    2016-04-01

    Vasospastic disorders are a common class of rheumatic disease. These include syndromes such as vegetative dystonia, Raynaud's syndrome, vibration disease and rheumatoid arthritis among others. The aim of this work is to develop an original method of diagnosing the functional state of peripheral vessels of the fingers, based on the simultaneous recording of LDF- and thermograms during the occlusion test, for determining vascular disorders of rheumatological patients. A diagnostic method was developed for assessing the functional state of the peripheral vessels of fingers, based on carrying out occlusion test in a thermally stabilized environment, with simultaneous recording of signals of laser Doppler flowmetry and skin thermometry. To verify the diagnostic value of the proposed method, a series of experiments were carried out on 41 rheumatological patients: 5 male and 36 females (average age 56.0+/-12.2 years). The most common diagnoses in the patient group were rheumatoid arthritis, arthrosis, gout and systemic lupus erythematosus. The laser analyser of blood microcirculation "LAKK-02" (SPE "LAZMA" Ltd, Russia) and a custom developed multi-channel thermometry device for low inertia thermometry were used for experimental measurements. The measurements of cutaneous temperature and the index of microcirculation were performed on the distal phalanx of the third finger of the right hand. Occlusion tests were performed with water baths at 25 and 42 °C and a tonometer cuff with a pressure of 200-220 mmHg for 3 min on the upper arm. The results of experimental studies are presented and interpreted. These data indicate a violation of the blood supply regulation in the form of a pronounced tendency towards microvascular vasoconstriction in the fingers. Thus, the response displaying a tendency toward angiospasm among patients in the rheumatological diseases profile group was observed mainly in the most severe cases (49 % of this group). The prospects of the developed

  9. Performance-based Physical Functioning and Peripheral Neuropathy in a Population-based Cohort of Women at Midlife

    PubMed Central

    Ylitalo, Kelly R.; Herman, William H.; Harlow, Siobán D.

    2013-01-01

    Peripheral neuropathy is underappreciated as a potential cause of functional limitations. In the present article, we assessed the cross-sectional association between peripheral neuropathy and physical functioning and how the longitudinal association between age and functioning differed by neuropathy status. Physical functioning was measured in 1996–2008 using timed performances on stair-climb, walking, sit-to-stand, and balance tests at the Michigan site of the Study of Women's Health Across the Nation, a population-based cohort study of women at midlife (n = 396). Peripheral neuropathy was measured in 2008 and defined as having an abnormal monofilament test result or 4 or more symptoms. We used linear mixed models to determine whether trajectories of physical functioning differed by prevalent neuropathy status. Overall, 27.8% of the women had neuropathy. Stair-climb time differed by neuropathy status (P = 0.04), and for every 1-year increase in age, women with neuropathy had a 1.82% (95% confidence interval: 1.42, 2.21) increase compared with a 0.95% (95% confidence interval: 0.71, 1.20) increase for women without neuropathy. Sit-to-stand time differed by neuropathy status (P = 0.01), but the rate of change did not differ. No differences between neuropathy groups were observed for the walk test. For some performance-based tasks, poor functioning was maintained or exacerbated for women who had prevalent neuropathy. Peripheral neuropathy may play a role in physical functioning limitations and future disability. PMID:23524038

  10. Genetic Variation in Vascular Endothelial Growth Factor-A and Lung Function

    PubMed Central

    Custovic, Adnan; Tepper, Robert; Graves, Penelope; Stern, Debra A.; Jones, Marcus; Hankinson, Jenny; Curtin, John A.; Wu, Jiakai; Blekic, Mario; Bukvic, Blazenka Kljaic; Aberle, Neda; Marinho, Susana; Belgrave, Danielle; Morgan, Wayne J.; Martinez, Fernando D.

    2012-01-01

    Rationale: Given the role of vascular endothelial growth factor (VEGF) in lung development, we hypothesized that polymorphisms in VEGF-A may be associated with lung function. Objectives: The current study was designed to assess the role of genetic variants in VEGF-A as determinants of airway function from infancy through early adulthood. Methods: Association between five single-nucleotide polymorphisms (SNPs) in VEGF-A and lung function were assessed longitudinally in two unselected birth cohorts and cross-sectionally among infants. Replication with two SNPs was conducted in adults and children with asthma. We investigated the functionality of the SNP most consistently associated with lung function (rs3025028) using Western blotting to measure the ratio of plasma VEGF-A165b/panVEGF-A165 among homozygotes. Measurements and Main Results: In two populations in infancy, C-allele homozygotes of rs3025028 had significantly higher VmaxFRC, forced expiratory flow50, and forced expiratory flow25–75 compared with other genotype groups. Among preschool children (age 3 yr), C allele of rs3025028 was associated with significantly higher specific airway conductance, with similar findings observed for lung function in school-age children. For FEV1/FVC ratio similar findings were observed among adolescents and young adults (birth cohort), and then replicated in adults and schoolchildren with asthma (cross-sectional studies). For rs3025038, plasma VEGF-A165b/panVEGF-A165 was significantly higher among CC versus GG homozygotes (P ≤ 0.02) at birth, in school-age children, and in adults. Conclusions: We report significant associations between VEGF-A SNP rs3025028 and parameters of airway function measured throughout childhood, with the effect persisting into adulthood. We propose that the mechanism may be mediated through the ratios of active and inhibitory isoforms of VEGF-A165, which may be determined by alternative splicing. PMID:22461367

  11. S-glutathionylation uncouples eNOS and regulates its cellular and vascular function

    PubMed Central

    Chen, Chun-An; Wang, Tse-Yao; Varadharaj, Saradhadevi; Reyes, Levy A.; Hemann, Craig; Hassan Talukder, M. A.; Chen, Yeong-Renn; Druhan, Lawrence J.; Zweier, Jay L.

    2012-01-01

    Endothelial nitric oxide synthase (eNOS) is critical in the regulation of vascular function, and can generate both nitric oxide (NO) and superoxide (O2•−), which are key mediators of cellular signalling. In the presence of Ca2+/calmodulin, eNOS produces NO, endothelial-derived relaxing factor, from L-arginine (L-Arg) by means of electron transfer from NADPH through a flavin containing reductase domain to oxygen bound at the haem of an oxygenase domain, which also contains binding sites for tetrahydrobiopterin (BH4) and L-Arg1–3. In the absence of BH4, NO synthesis is abrogated and instead O2•− is generated4–7. While NOS dysfunction occurs in diseases with redox stress, BH4 repletion only partly restores NOS activity and NOS-dependent vasodilation7. This suggests that there is an as yet unidentified redox-regulated mechanism controlling NOS function. Protein thiols can undergo S-glutathionylation, a reversible protein modification involved in cellular signalling and adaptation8,9. Under oxidative stress, S-glutathionylation occurs through thiol–disulphide exchange with oxidized glutathione or reaction of oxidant-induced protein thiyl radicals with reduced glutathione10,11. Cysteine residues are critical for the maintenance of eNOS function12,13; we therefore speculated that oxidative stress could alter eNOS activity through S-glutathionylation. Here we show that S-glutathionylation of eNOS reversibly decreases NOS activity with an increase in O2•− generation primarily from the reductase, in which two highly conserved cysteine residues are identified as sites of S-glutathionylation and found to be critical for redox-regulation of eNOS function. We show that eNOS S-glutathionylation in endothelial cells, with loss of NO and gain of O2•− generation, is associated with impaired endothelium-dependent vasodilation. In hypertensive vessels, eNOS S-glutathionylation is increased with impaired endothelium-dependent vasodilation that is restored by thiol

  12. Changes of Number and Function of Late Endothelial Progenitor Cells in Peripheral Blood of COPD Patients Combined with Pulmonary Hypertension.

    PubMed

    Liu, Pei; Zhang, Hongmei; Liu, Jianxin; Sheng, Chunfeng; Zhang, Linlin; Zeng, Yanjun

    2016-06-01

    Objective The objective of this study was to investigate the changes of number and function of late endothelial progenitor cells (EPCs) in peripheral blood of chronic obstructive pulmonary disease (COPD) patients combined with pulmonary hypertension. Subjects and Methods The study enrolled 120 cases including 40 non-COPD and pulmonary arterial hypertension (PAH) patients (non-COPD group), 40 COPD non-PAH patients (COPD group), and 40 COPD patients combined with PAH (COPD + PAH group). Peripheral blood mononuclear cells were separated by density gradient centrifugation, cultured for 21 days, and then identified as late endothelial progenitor cells. The cell colonies were counted. MTT assay, modified Boyden chamber assay, and human fibronectin plates were used to measure the proliferation, migration, and adhesion functions of the late endothelial progenitor cells, respectively. Results Compared with non-COPD and COPD groups, the number of peripheral blood late EPCs in COPD + PAH group was significantly reduced, and the proliferation, adhesion, and migration capacities were significantly lowered; the differences were statistically significant (p < 0.05). The number and function of late EPCs decreased with the increase of pulmonary artery pressure (p < 0.05). Conclusion The number of late EPCs in COPD patients combined with pulmonary hypertension was reduced, which implies the impaired cell functions. The changes of number and function were negatively correlated with the severity of pulmonary hypertension. PMID:25226359

  13. Treated effect of silymarin on vascular function of aged rats: Dependant on nitric oxide pathway.

    PubMed

    Demirci, Buket; Demir, Omer; Dost, Turhan; Birincioglu, Mustafa

    2013-11-01

    Abstract Context: Aging leads to endothelial dysfunction and vascular stiffness which are the main causes of many cardiovascular diseases. Previous reports have shown that the cell protective effect of silymarin (SM) is dependent on its antioxidant properties. Objectives: We investigated the effect of SM on vascular functions of aged rats and the involvement of nitric oxide or cyclooxygenase (COX) activity in this effect. Materials and methods: Isolated rat aortas were obtained from 22-month old rats. Each ring was incubated with SM (50 mg/L), SM/l-nitro-arginine methyl ester (100 μM, l-NAME) or SM/indomethacin (10 μM, INDO) in tissue bath. Three- to four-month-old rats were used as young controls. Endothelium-intact rings were precontracted with α-receptor agonist phenylephrine (0.001-30 µM) or voltage-dependent high potassium (40 mM), endothelium dependent/independent relaxant responses were obtained using acetylcholine (0.001-30 µM) and sodium nitroprusside (0.0001-3 µM), respectively. Results: Aging increased phenylephrine sensitivity (6.45 ± 0.08; 6.88 ± 0.09) and decreased KCl contraction (882 ± 118.4; 499 ± 80.4). SM treatment decreased the Emax of both agents (548 ± 109; 223 ± 48.9). Aging deteriorated acetylcholine relaxation (93.9 ± 2.09; 72.0 ± 2.56) and SM improved the response (86.3 ± 1.90). l-NAME prevented the SM effect whereas INDO was ineffective. Discussion and Conclusion: Immediate SM treatment partially restored endothelial dysfunction and vascular tone in aging. The possible mechanism might not be mediated by prostacyclin or the COX pathway in acute administration; the nitric oxide pathway and calcium antagonistic features of SM relate to its action on the vessel. PMID:24188646

  14. Heat acclimation improves cutaneous vascular function and sweating in trained cyclists

    PubMed Central

    Lorenzo, Santiago

    2010-01-01

    The aim of this study was to explore heat acclimation effects on cutaneous vascular responses and sweating to local ACh infusions and local heating. We also sought to examine whether heat acclimation altered maximal skin blood flow. ACh (1, 10, and 100 mM) was infused in 20 highly trained cyclists via microdialysis before and after a 10-day heat acclimation program [two 45-min exercise bouts at 50% maximal O2 uptake (V̇o2max) in 40°C (n = 12)] or control conditions [two 45-min exercise bouts at 50% V̇o2max in 13°C (n = 8)]. Skin blood flow was monitored via laser-Doppler flowmetry (LDF), and cutaneous vascular conductance (CVC) was calculated as LDF ÷ mean arterial pressure. Sweat rate was measured by resistance hygrometry. Maximal brachial artery blood flow (forearm blood flow) was obtained by heating the contralateral forearm in a water spray device and measured by Doppler ultrasound. Heat acclimation increased %CVCmax responses to 1, 10, and 100 mM ACh (43.5 ± 3.4 vs. 52.6 ± 2.6% CVCmax, 67.7 ± 3.4 vs. 78.0 ± 3.0% CVCmax, and 81.0 ± 3.8 vs. 88.5 ± 1.1% CVCmax, respectively, all P < 0.05). Maximal forearm blood flow remained unchanged after heat acclimation (290.9 ± 12.7 vs. 269.9 ± 23.6 ml/min). The experimental group showed significant increases in sweating responses to 10 and 100 mM ACh (0.21 ± 0.03 vs. 0.31 ± 0.03 mg·cm−2·min−1 and 0.45 ± 0.05 vs. 0.67 ± 0.06 mg·cm−2·min−1, respectively, all P < 0.05), but not to 1 mM ACh (0.13 ± 0.02 vs. 0.18 ± 0.02 mg·cm−2·min−1, P = 0.147). No differences in any of the variables were found in the control group. Heat acclimation in highly trained subjects induced local adaptations within the skin microcirculation and sweat gland apparatus. Furthermore, maximal skin blood flow was not altered by heat acclimation, demonstrating that the observed changes were attributable to improvement in cutaneous vascular function and not to structural changes that limit maximal vasodilator capacity

  15. Vascular dysregulation in normal-tension glaucoma is not affected by structure and function of the microcirculation or macrocirculation at rest: a case-control study.

    PubMed

    Bossuyt, Jelle; Vandekerckhove, Gwendolijn; De Backer, Tine L M; Van de Velde, Sandrien; Azermai, Majda; Stevens, Anna-Maria; Kestelyn, Philippe; Raemdonck, Tia; Segers, Patrick; Vanmolkot, Floris; Van Bortel, Luc M

    2015-01-01

    In normal-tension glaucoma (NTG), optic nerve damage occurs despite a normal intraocular pressure. Studies implicating systemic blood pressure or, more recently, arterial stiffness in the pathophysiology of NTG have produced conflicting results. Our aim was to investigate whether NTG is associated with alterations in the macrocirculation or microcirculation, cardiac function, and peripheral and central hemodynamics. Thirty patients with NTG (mean age 65 years, range 46-79) and 33 healthy subjects (mean age 67 years, range 42-79) matched for age and sex were included in the study. Exclusion criteria (for both cases and controls) were history of cardiovascular disease, diabetes mellitus, severe hypertension, and hypercholesterolemia. Aortic stiffness was measured using carotid-femoral pulse wave velocity (PWV), central hemodynamics using carotid artery applanation tonometry, and diameter, stiffness, and intima-media thickness (IMT) of the carotid and femoral artery using echo-tracking. Total peripheral resistance index (TPRI) was derived from mean arterial pressure and cardiac index, measured using ultrasound. There were no statistically significant differences in arterial structure nor function between NTG patients and age and sex-matched controls. NTG versus controls, respectively: brachial blood pressure 126 ± 15/77 ± 8 versus 127 ± 16/76 ± 7 mm Hg, P = 0.81; carotid-femoral PWV 9.8 ± 2.1 versus 10.1 ± 1.9 m/s, P = 0.60; TPRI 1833 ± 609 versus 1779 ± 602 dyne.s/cm5/m2, P = 0.79; and carotid IMT 0.65 ± 0.14 versus 0.68 ± 0.13 mm, P = 0.39. This study could not show an association of NTG with altered IMT, arterial stiffness, total peripheral resistance, cardiac output, and peripheral or central hemodynamics at rest. Although the majority of these NTG patients do exhibit symptoms of vascular dysregulation, in the present study this was not translated into alterations in the microcirculation or macrocirculation at rest. PMID:25590850

  16. Peripheral artery bypass - leg - discharge

    MedlinePlus

    ... P. Peripheral arterial diseases. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's ... noncoronary obstructive vascular disease. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's ...

  17. Metabolic rate and vascular function are reduced in women with a family history of type 2 diabetes mellitus.

    PubMed

    Olive, Jennifer L; Ballard, Kevin D; Miller, James J; Milliner, Beth A

    2008-06-01

    Metabolic and vascular abnormalities have been found in individuals with type 2 diabetes mellitus (T2D). Family history is often associated with increased risk of the development of T2D. We sought to determine if young, sedentary, insulin-sensitive individuals with a family history of T2D (FH+) have a reduced resting energy expenditure (REE) and vascular endothelial function compared with individuals who have no family history of T2D (FH-). The REE was determined in 18 FH+ individuals and 15 FH- individuals using indirect open-circuit calorimetry. Vascular endothelial function was measured via flow-mediated dilation (FMD) of the brachial artery. C-reactive protein and interleukin-6 were also measured to look at vascular inflammation. Body composition was measured via bioelectrical impedance analysis to determine fat-free mass and fat mass for each individual. Insulin resistance was calculated using the homeostasis model assessment equation and fasting insulin and glucose concentrations. Subjects (n = 42) were approximately 26 years old and had normal fasting serum insulin or glucose concentrations. The REE normalized for body weight (kilocalories per day per kilogram body weight) was significantly reduced in the FH+ women compared with FH- women (P < .001) but not in the men. The FMD was significantly reduced (34.3%) in the FH+ group compared with the FH- in women (P = .002). However, no between-group difference in FMD was present in male subjects (P = .376). Young, healthy, insulin-sensitive women with a family history of T2D have reduced whole-body metabolic rate and vascular endothelial function compared with those with no family history of disease. These differences in whole-body metabolic rate and vascular endothelial function were not present in male subjects. PMID:18502267

  18. Construction of Large-Volume Tissue Mimics with 3D Functional Vascular Networks.

    PubMed

    Kang, Tae-Yun; Hong, Jung Min; Jung, Jin Woo; Kang, Hyun-Wook; Cho, Dong-Woo

    2016-01-01

    We used indirect stereolithography (SL) to form inner-layered fluidic networks in a porous scaffold by introducing a hydrogel barrier on the luminal surface, then seeded the networks separately with human umbilical vein endothelial cells and human lung fibroblasts to form a tissue mimic containing vascular networks. The artificial vascular networks provided channels for oxygen transport, thus reducing the hypoxic volume and preventing cell death. The endothelium of the vascular networks significantly retarded the occlusion of channels during whole-blood circulation. The tissue mimics have the potential to be used as an in vitro platform to examine the physiologic and pathologic phenomena through vascular architecture. PMID:27228079

  19. Construction of Large-Volume Tissue Mimics with 3D Functional Vascular Networks

    PubMed Central

    Kang, Tae-Yun; Hong, Jung Min; Jung, Jin Woo; Kang, Hyun-Wook; Cho, Dong-Woo

    2016-01-01

    We used indirect stereolithography (SL) to form inner-layered fluidic networks in a porous scaffold by introducing a hydrogel barrier on the luminal surface, then seeded the networks separately with human umbilical vein endothelial cells and human lung fibroblasts to form a tissue mimic containing vascular networks. The artificial vascular networks provided channels for oxygen transport, thus reducing the hypoxic volume and preventing cell death. The endothelium of the vascular networks significantly retarded the occlusion of channels during whole-blood circulation. The tissue mimics have the potential to be used as an in vitro platform to examine the physiologic and pathologic phenomena through vascular architecture. PMID:27228079

  20. Hydrogen sulfide replacement therapy protects the vascular endothelium in hyperglycemia by preserving mitochondrial function.

    PubMed

    Suzuki, Kunihiro; Olah, Gabor; Modis, Katalin; Coletta, Ciro; Kulp, Gabriella; Gerö, Domokos; Szoleczky, Petra; Chang, Tuanjie; Zhou, Zongmin; Wu, Lingyun; Wang, Rui; Papapetropoulos, Andreas; Szabo, Csaba

    2011-08-16

    The goal of the present studies was to investigate the role of changes in hydrogen sulfide (H(2)S) homeostasis in the pathogenesis of hyperglycemic endothelial dysfunction. Exposure of bEnd3 microvascular endothelial cells to elevated extracellular glucose (in vitro "hyperglycemia") induced the mitochondrial formation of reactive oxygen species (ROS), which resulted in an increased consumption of endogenous and exogenous H(2)S. Replacement of H(2)S or overexpression of the H(2)S-producing enzyme cystathionine-γ-lyase (CSE) attenuated the hyperglycemia-induced enhancement of ROS formation, attenuated nuclear DNA injury, reduced the activation of the nuclear enzyme poly(ADP-ribose) polymerase, and improved cellular viability. In vitro hyperglycemia resulted in a switch from oxidative phosphorylation to glycolysis, an effect that was partially corrected by H(2)S supplementation. Exposure of isolated vascular rings to high glucose in vitro induced an impairment of endothelium-dependent relaxations, which was prevented by CSE overexpression or H(2)S supplementation. siRNA silencing of CSE exacerbated ROS production in hyperglycemic endothelial cells. Vascular rings from CSE(-/-) mice exhibited an accelerated impairment of endothelium-dependent relaxations in response to in vitro hyperglycemia, compared with wild-type controls. Streptozotocin-induced diabetes in rats resulted in a decrease in the circulating level of H(2)S; replacement of H(2)S protected from the development of endothelial dysfunction ex vivo. In conclusion, endogenously produced H(2)S protects against the development of hyperglycemia-induced endothelial dysfunction. We hypothesize that, in hyperglycemic endothelial cells, mitochondrial ROS production and increased H(2)S catabolism form a positive feed-forward cycle. H(2)S replacement protects against these alterations, resulting in reduced ROS formation, improved endothelial metabolic state, and maintenance of normal endothelial function. PMID:21808008

  1. Effects of resistance training combined with vascular occlusion or hypoxia on neuromuscular function in athletes.

    PubMed

    Manimmanakorn, Apiwan; Manimmanakorn, Nuttaset; Taylor, Robert; Draper, Nick; Billaut, Francois; Shearman, Jeremy P; Hamlin, Michael J

    2013-07-01

    The aim was to investigate the effects of low-load resistant training combined with vascular occlusion or normobaric hypoxic exposure, on neuromuscular function. In a randomised controlled trial, well-trained athletes took part in a 5-week training of knee flexor/extensor muscles in which low-load resistant exercise (20% of one repetition maximum, 1-RM) was combined with either (1) an occlusion pressure of approximately 230 mmHg (KT, n = 10), (2) hypoxic air to generate an arterial blood oxygen saturation of ~80% (HT, n = 10), or (3) with no additional stimulus (CT, n = 10). Before and after training, participants completed the following tests: 3-s maximal voluntary contraction (MVC₃), 30-s MVC, and an endurance test (maximal number of repetitions at 20% 1-RM, Reps₂₀). Electromyographic activity (root mean square, RMS) was measured during tests and the cross-sectional area (CSA) of the quadriceps and hamstrings was measured pre- and post-training. Relative to CT, KT, and HT showed likely increases in MVC₃ (11.0 ± 11.9 and 15.0 ± 13.1%, mean ± 90% confidence interval), MVC₃₀ (10.2 ± 9.0 and 18.3 ± 17.4%), and Reps₂₀ (28.9 ± 23.7 and 23.3 ± 24.0%). Compared to the CT group, CSA increased in the KT (7.6 ± 5.8) and HT groups (5.3 ± 3.0). KT had a large effect on RMS during MVC₃, compared to CT (effect size 0.8) and HT (effect size 0.8). We suspect hypoxic conditions created within the muscles during vascular occlusion and hypoxic training may play a key role in these performance enhancements. PMID:23412543

  2. Structural and Functional Vascular Alterations and Incident Hypertension in Normotensive Adults

    PubMed Central

    Peralta, Carmen A.; Adeney, Kathryn L.; Shlipak, Michael G.; Jacobs, David; Duprez, Daniel; Bluemke, David; Polak, Joseph; Psaty, Bruce; Kestenbaum, Bryan R.

    2010-01-01

    Vascular abnormalities may exist before clinical hypertension. Using Poisson regression, the authors studied the association of coronary artery calcium (CAC), common carotid intima-media thickness (CIMT), aortic distensibility, and large and small arterial elasticity with incident hypertension among 2,512 normotensive US adults free of cardiovascular disease. Incidence rate ratios for incident hypertension (blood pressure ≥140/90 mm Hg or new antihypertensive medication) were calculated. Increased CAC was associated with incident hypertension in demographics-adjusted models (incidence rate ratio (IRR) = 1.35, 95% confidence interval (CI): 1.04, 1.75; IRR = 1.35, 95% CI: 1.02, 1.78; and IRR = 1.59, 95% CI: 1.12, 2.25 for CAC scores of 30–99, 100–399, and ≥400, respectively) but was attenuated after further adjustment. Increased common CIMT was associated with incident hypertension (IRR = 1.77, 95% CI: 1.28, 2.46 for quintile 4; IRR = 1.80, 95% CI: 1.28, 2.53 for quintile 5). Participants with the lowest, compared with the highest, aortic distensibility had an increased risk of hypertension (IRR = 1.75, 95% CI: 1.10, 2.79), as did those with the lowest large arterial elasticity (IRR = 1.49, 95% CI: 1.11, 1.99). Lower small arterial elasticity was incrementally associated with incident hypertension starting at quintile 2 (IRR = 2.01, 95% CI: 1.39, 2.91; IRR = 2.47, 95% CI: 1.71, 3.57; IRR = 2.73, 95% CI: 1.88, 3.95; and IRR = 2.85, 95% CI: 1.95, 4.16). Structural and functional vascular abnormalities are independent predictors of incident hypertension. These findings are important for understanding the pathogenesis of hypertension. PMID:19951938

  3. Nitroso-Redox Status and Vascular Function in Marginal and Severe Ascorbate Deficiency

    PubMed Central

    Garcia-Saura, Maria-Francisca; Saijo, Fumito; Bryan, Nathan S.; Bauer, Selena; Rodriguez, Juan

    2012-01-01

    Abstract Marginal vitamin C (ascorbic acid) deficiency is a prevalent yet underappreciated risk factor for cardiovascular disease. Along with glutathione, ascorbate plays important roles in antioxidant defense and redox signaling. Production of nitric oxide (NO) and reactive oxygen species and their interaction, giving rise to nitroso and nitrosyl product formation, are key components of the redox regulation/signaling network. Numerous in vitro studies have demonstrated that these systems are interconnected via multiple chemical transformation reactions, but little is known about their dynamics and significance in vivo. Aims: We sought to investigate the time-course of changes in NO/redox status and vascular function during ascorbate depletion in rats unable to synthesize vitamin C. Results: We here show that both redox and protein nitros(yl)ation status in blood and vital organs vary dynamically during development of ascorbate deficiency. Prolonged marginal ascorbate deficiency is associated with cell/tissue-specific perturbations in ascorbate and glutathione redox and NO status. Scurvy develops earlier in marginally deficient compared to adequately supplemented animals, with blunted compensatory NO production and a dissociation of biochemistry from clinical symptomology in the former. Paradoxically, aortic endothelial reactivity is enhanced rather than impaired, irrespective of ascorbate status. Innovation/Conclusion: Enhanced NO production and protein nitros(yl)ation are integral responses to the redox stress of acute ascorbate deprivation. The elevated cardiovascular risk in marginal ascorbate deficiency is likely to be associated with perturbations of NO/redox-sensitive signaling nodes unrelated to the regulation of vascular tone. This new model may have merit for the future study of redox-sensitive events in marginal ascorbate deficiency. Antioxid. Redox Signal. 17, 937–950. PMID:22304648

  4. Impaired Coronary and Renal Vascular Function in Spontaneously Type 2 Diabetic Leptin-Deficient Mice

    PubMed Central

    Westergren, Helena U.; Grönros, Julia; Heinonen, Suvi E.; Miliotis, Tasso; Jennbacken, Karin; Sabirsh, Alan; Ericsson, Anette; Jönsson-Rylander, Ann-Cathrine; Svedlund, Sara; Gan, Li-Ming

    2015-01-01

    Background Type 2 diabetes is associated with macro- and microvascular complications in man. Microvascular dysfunction affects both cardiac and renal function and is now recognized as a main driver of cardiovascular mortality and morbidity. However, progression of microvascular dysfunction in experimental models is often obscured by macrovascular pathology and consequently demanding to study. The obese type 2 diabetic leptin-deficient (ob/ob) mouse lacks macrovascular complications, i.e. occlusive atherosclerotic disease, and may therefore be a potential model for microvascular dysfunction. The present study aimed to test the hypothesis that these mice with an insulin resistant phenotype might display microvascular dysfunction in both coronary and renal vascular beds. Methods and Results In this study we used non-invasive Doppler ultrasound imaging to characterize microvascular dysfunction during the progression of diabetes in ob/ob mice. Impaired coronary flow velocity reserve was observed in the ob/ob mice at 16 and 21 weeks of age compared to lean controls. In addition, renal resistivity index as well as pulsatility index was higher in the ob/ob mice at 21 weeks compared to lean controls. Moreover, plasma L-arginine was lower in ob/ob mice, while asymmetric dimethylarginine was unaltered. Furthermore, a decrease in renal vascular density was observed in the ob/ob mice. Conclusion In parallel to previously described metabolic disturbances, the leptin-deficient ob/ob mice also display cardiac and renal microvascular dysfunction. This model may therefore be suitable for translational, mechanistic and interventional studies to improve the understanding of microvascular complications in type 2 diabetes. PMID:26098416

  5. Peripheral chemoreceptor control of cardiovascular function at rest and during exercise in heart failure patients.

    PubMed

    Edgell, Heather; McMurtry, M Sean; Haykowsky, Mark J; Paterson, Ian; Ezekowitz, Justin A; Dyck, Jason R B; Stickland, Michael K

    2015-04-01

    Peripheral chemoreceptor activity/sensitivity is enhanced in chronic heart failure (HF), and sensitivity is linked to greater mortality. This study aimed to determine the role of the peripheral chemoreceptor in cardiovascular control at rest and during exercise in HF patients and controls. Clinically stable HF patients (n = 11; ejection fraction: 39 ± 5%) and risk-matched controls (n = 10; ejection fraction: 65 ± 2%) performed randomized trials with or without dopamine infusion (2 μg·min(-1)·kg(-1)) at rest and during 40% maximal voluntary contraction handgrip (HG) exercise, and a resting trial of 2 min of inspired 100% oxygen. Both dopamine and hyperoxia were used to inhibit the peripheral chemoreceptor. At rest in HF patients, dopamine decreased ventilation (P = 0.02), decreased total peripheral resistance index (P = 0.003), and increased cardiac and stroke indexes (P ≤ 0.01), yet there was no effect of dopamine on these variables in controls (P ≥ 0.7). Hyperoxia lowered ventilation in HF (P = 0.01), but not in controls (P = 0.9), indicating suppression of the peripheral chemoreceptors in HF. However, no decrease of total peripheral resistance index was observed in HF. As expected, HG increased heart rate, ventilation, and brachial conductance of the nonexercising arm in controls and HF patients. During dopamine infusion, there were no changes in mean arterial pressure, heart rate, or ventilation responses to HG in either group (P ≥ 0.26); however, brachial conductance increased with dopamine in the control group (P = 0.004), but decreased in HF (P = 0.02). Our findings indicate that the peripheral chemoreceptor contributes to cardiovascular control at rest in HF patients and during exercise in risk-matched controls. PMID:25614600

  6. Smooth Muscle-Targeted Overexpression of Peroxisome Proliferator Activated Receptor-γ Disrupts Vascular Wall Structure and Function

    PubMed Central

    Kleinhenz, Jennifer M.; Murphy, Tamara C.; Pokutta-Paskaleva, Anastassia P.; Gleason, Rudolph L.; Lyle, Alicia N.; Taylor, W. Robert; Blount, Mitsi A.; Cheng, Juan; Yang, Qinglin; Sutliff, Roy L.; Hart, C. Michael

    2015-01-01

    Activation of the nuclear hormone receptor, PPARγ, with pharmacological agonists promotes a contractile vascular smooth muscle cell phenotype and reduces oxidative stress and cell proliferation, particularly under pathological conditions including vascular injury, restenosis, and atherosclerosis. However, pharmacological agonists activate both PPARγ-dependent and -independent mechanisms in multiple cell types confounding efforts to clarify the precise role of PPARγ in smooth muscle cell structure and function in vivo. We, therefore, designed and characterized a mouse model with smooth muscle cell-targeted PPARγ overexpression (smPPARγOE). Our results demonstrate that smPPARγOE attenuated contractile responses in aortic rings, increased aortic compliance, caused aortic dilatation, and reduced mean arterial pressure. Molecular characterization revealed that compared to littermate control mice, aortas from smPPARγOE mice expressed lower levels of contractile proteins and increased levels of adipocyte-specific transcripts. Morphological analysis demonstrated increased lipid deposition in the vascular media and in smooth muscle of extravascular tissues. In vitro adenoviral-mediated PPARγ overexpression in human aortic smooth muscle cells similarly increased adipocyte markers and lipid uptake. The findings demonstrate that smooth muscle PPARγ overexpression disrupts vascular wall structure and function, emphasizing that balanced PPARγ activity is essential for vascular smooth muscle homeostasis. PMID:26451838

  7. Effect of Delayed Peripheral Nerve Repair on Nerve Regeneration, Schwann Cell Function and Target Muscle Recovery

    PubMed Central

    Jonsson, Samuel; Wiberg, Rebecca; McGrath, Aleksandra M.; Novikov, Lev N.; Wiberg, Mikael; Novikova, Liudmila N.; Kingham, Paul J.

    2013-01-01

    Despite advances in surgical techniques for peripheral nerve repair, functional restitution remains incomplete. The timing of surgery is one factor influencing the extent of recovery but it is not yet clearly defined how long a delay may be tolerated before repair becomes futile. In this study, rats underwent sciatic nerve transection before immediate (0) or 1, 3, or 6 months delayed repair with a nerve graft. Regeneration of spinal motoneurons, 13 weeks after nerve repair, was assessed using retrograde labeling. Nerve tissue was also collected from the proximal and distal stumps and from the nerve graft, together with the medial gastrocnemius (MG) muscles. A dramatic decline in the number of regenerating motoneurons and myelinated axons in the distal nerve stump was observed in the 3- and 6-months delayed groups. After 3 months delay, the axonal number in the proximal stump increased 2–3 folds, accompanied by a smaller axonal area. RT-PCR of distal nerve segments revealed a decline in Schwann cells (SC) markers, most notably in the 3 and 6 month delayed repair samples. There was also a progressive increase in fibrosis and proteoglycan scar markers in the distal nerve with increased delayed repair time. The yield of SC isolated from the distal nerve segments progressively fell with increased delay in repair time but cultured SC from all groups proliferated at similar rates. MG muscle at 3- and 6-months delay repair showed a significant decline in weight (61% and 27% compared with contra-lateral side). Muscle fiber atrophy and changes to neuromuscular junctions were observed with increased delayed repair time suggestive of progressively impaired reinnervation. This study demonstrates that one of the main limiting factors for nerve regeneration after delayed repair is the distal stump. The critical time point after which the outcome of regeneration becomes too poor appears to be 3-months. PMID:23409189

  8. Effects of endotoxin exposure on cationic amino acid transporter function in ovine peripheral blood mononuclear cells.

    PubMed

    Clark, Megan F; Reade, Michael C; Boyd, C A R; Young, J Duncan

    2003-03-01

    Rodent models of sepsis differ from clinical human disease in that humans make substantially less whole-body nitric oxide and have different cellular responses to endotoxin. Sheep, when exposed to endotoxin, behave in a manner more similar to humans. Many studies of rodent peripheral blood mononuclear cells (PBMCs) exposed to endotoxin demonstrate increased cationic amino acid transporter function (particularly through the y+ transporter) to supply arginine substrate to upregulated nitric oxide synthase. Whether this is true in sheep is not known. We have studied cationic amino acid transport in sheep PBMCs stimulated with endotoxin, using labelled lysine. PBMCs stimulated both in vitro and in vivo show an initial reduction in total and y+ lysine transport (after 1-2 h exposure to endotoxin): a previously undescribed effect of endotoxin. In in vitro activated cells, the reduction in y+ transport was prevented by the lipoxygenase inhibitor, nordihydroguaretic acid (NDGA), and the phospholipase inhibitor 4-bromophenacyl bromide (4-BPAB), but not cyclohexamide or a number of other inhibitors of intracellular second-messenger pathways. In contrast after 14 h incubation, the expected increase in total and y+ lysine transport was seen. The increase in y+ transport could be prevented by cyclohexamide, dexamethasone, ibuprofen, the protein kinase C inhibitor sphingosine, NDGA and 4-BPAB. These results suggest that in response to endotoxin exposure there is an initial decrease in y+ activity mediated by a lipoxygenase product, followed by a substantial increase in y+ activity mediated by the products of either cyclo-oxygenase or lipoxygenase. Cyclo-oxygenase and/or lipoxygenase inhibition might be useful in reducing arginine transport, and hence nitric oxide production, in these cells. PMID:12621525

  9. Mechanics and Function of the Pulmonary Vasculature: Implications for Pulmonary Vascular Disease and Right Ventricular Function

    PubMed Central

    Lammers, Steven; Scott, Devon; Hunter, Kendall; Tan, Wei; Shandas, Robin; Stenmark, Kurt R.

    2012-01-01

    The relationship between cardiac function and the afterload against which the heart muscle must work to circulate blood throughout the pulmonary circulation is defined by a complex interaction between many coupled system parameters. These parameters range broadly and incorporate system effects originating primarily from three distinct locations: input power from the heart, hydraulic impedance from the large conduit pulmonary arteries, and hydraulic resistance from the more distal microcirculation. These organ systems are not independent, but rather, form a coupled system in which a change to any individual parameter affects all other system parameters. The result is a highly nonlinear system which requires not only detailed study of each specific component and the effect of disease on their specific function, but also requires study of the interconnected relationship between the microcirculation, the conduit arteries, and the heart in response to age and disease. Here, we investigate systems-level changes associated with pulmonary hypertensive disease progression in an effort to better understand this coupled relationship. PMID:23487595

  10. Integrated Evaluation of Age-Related Changes in Structural and Functional Vascular Parameters Used to Assess Arterial Aging, Subclinical Atherosclerosis, and Cardiovascular Risk in Uruguayan Adults: CUiiDARTE Project

    PubMed Central

    Bia, Daniel; Zócalo, Yanina; Farro, Ignacio; Torrado, Juan; Farro, Federico; Florio, Lucía; Olascoaga, Alicia; Brum, Javier; Alallón, Walter; Negreira, Carlos; Lluberas, Ricardo; Armentano, Ricardo L.

    2011-01-01

    This work was carried out in a Uruguayan (South American) population to characterize aging-associated physiological arterial changes. Parameters markers of subclinical atherosclerosis and that associate age-related changes were evaluated in healthy people. A conservative approach was used and people with nonphysiological and pathological conditions were excluded. Then, we excluded subjects with (a) cardiovascular (CV) symptoms, (b) CV disease, (c) diabetes mellitus or renal failure, and (d) traditional CV risk factors (other than age and gender). Subjects (n = 388) were submitted to non-invasive vascular studies (gold-standard techniques), to evaluate (1) common (CCA), internal, and external carotid plaque prevalence, (2) CCA intima-media thickness and diameter, (3) CCA stiffness (percentual pulsatility, compliance, distensibility, and stiffness index), (4) aortic stiffness (carotid-femoral pulse wave velocity), and (5) peripheral and central pressure wave-derived parameters. Age groups: ≤20, 21–30, 31–40, 41–50, 51–60, 61–70, and 71–80 years old. Age-related structural and functional vascular parameters profiles were obtained and analyzed considering data from other populations. The work has the strength of being the first, in Latin America, that uses an integrative approach to characterize vascular aging-related changes. Data could be used to define vascular aging and abnormal or disease-related changes. PMID:22187622

  11. Integrated Evaluation of Age-Related Changes in Structural and Functional Vascular Parameters Used to Assess Arterial Aging, Subclinical Atherosclerosis, and Cardiovascular Risk in Uruguayan Adults: CUiiDARTE Project.

    PubMed

    Bia, Daniel; Zócalo, Yanina; Farro, Ignacio; Torrado, Juan; Farro, Federico; Florio, Lucía; Olascoaga, Alicia; Brum, Javier; Alallón, Walter; Negreira, Carlos; Lluberas, Ricardo; Armentano, Ricardo L

    2011-01-01

    This work was carried out in a Uruguayan (South American) population to characterize aging-associated physiological arterial changes. Parameters markers of subclinical atherosclerosis and that associate age-related changes were evaluated in healthy people. A conservative approach was used and people with nonphysiological and pathological conditions were excluded. Then, we excluded subjects with (a) cardiovascular (CV) symptoms, (b) CV disease, (c) diabetes mellitus or renal failure, and (d) traditional CV risk factors (other than age and gender). Subjects (n = 388) were submitted to non-invasive vascular studies (gold-standard techniques), to evaluate (1) common (CCA), internal, and external carotid plaque prevalence, (2) CCA intima-media thickness and diameter, (3) CCA stiffness (percentual pulsatility, compliance, distensibility, and stiffness index), (4) aortic stiffness (carotid-femoral pulse wave velocity), and (5) peripheral and central pressure wave-derived parameters. Age groups: ≤20, 21-30, 31-40, 41-50, 51-60, 61-70, and 71-80 years old. Age-related structural and functional vascular parameters profiles were obtained and analyzed considering data from other populations. The work has the strength of being the first, in Latin America, that uses an integrative approach to characterize vascular aging-related changes. Data could be used to define vascular aging and abnormal or disease-related changes. PMID:22187622

  12. Exploration of the Rapid Effects of Personal Fine Particulate Matter Exposure on Hemodynamics and Vascular Function during the Same Day

    EPA Science Inventory

    Background: Levels of fine particulate matter [≤ 2.5 μm in aerodynamic diameter (PM2.5)] are associated with alterations in arterial hemodynamics and vascular function. However, the characteristics of the same-day exposure–response relationships remain unclear. Object...

  13. Integrin-specific hydrogels functionalized with VEGF for vascularization and bone regeneration of critical-size bone defects.

    PubMed

    García, José R; Clark, Amy Y; García, Andrés J

    2016-04-01

    Vascularization of bone defects is considered a crucial component to the successful regeneration of large bone defects. Although vascular endothelial growth factor (VEGF) has been delivered to critical-size bone defect models to augment blood vessel infiltration into the defect area, its potential to increase bone repair remains ambiguous. In this study, we investigated whether integrin-specific biomaterials modulate the effects of VEGF on bone regeneration. We engineered protease-degradable, VEGF-loaded poly(ethylene glycol) (PEG) hydrogels functionalized with either a triple-helical, α2 β1 integrin-specific peptide GGYGGGP(GPP)5 GFOGER(GPP)5 GPC (GFOGER) or an αv β3 integrin-targeting peptide GRGDSPC (RGD). Covalent incorporation of VEGF into the PEG hydrogel allowed for protease degradation-dependent release of the protein while maintaining VEGF bioactivity. When applied to critical-size segmental defects in the murine radius, GFOGER-functionalized VEGF-free hydrogels exhibited significantly increased vascular volume and density and resulted in a larger number of thicker blood vessels compared to RGD-functionalized VEGF-free hydrogels. VEGF-loaded RGD hydrogels increased vascularization compared to VEGF-free RGD hydrogels, but the levels of vascularization for these VEGF-containing RGD hydrogels were similar to those of VEGF-free GFOGER hydrogels. VEGF transiently increased bone regeneration in RGD hydrogels but had no effect at later time points. In GFOGER hydrogels, VEGF did not show an effect on bone regeneration. However, VEGF-free GFOGER hydrogels resulted in increased bone regeneration compared to VEGF-free RGD hydrogels. These findings demonstrate the importance of integrin-specificity in engineering constructs for vascularization and associated bone regeneration. PMID:26662727

  14. Vascular functioning and the water balance of ripening kiwifruit (Actinidia chinensis) berries

    PubMed Central

    Clearwater, Michael J.; Luo, Zhiwei; Ong, Sam Eng Chye; Blattmann, Peter; Thorp, T. Grant

    2012-01-01

    Indirect evidence suggests that water supply to fleshy fruits during the final stages of development occurs through the phloem, with the xylem providing little water, or acting as a pathway for water loss back to the plant. This inference was tested by examining the water balance and vascular functioning of ripening kiwifruit berries (Actinidia chinensis var. chinensis ‘Hort16A’) exhibiting a pre-harvest ‘shrivel’ disorder in California, and normal development in New Zealand. Dye labelling and mass balance experiments indicated that the xylem and phloem were both functional and contributed approximately equally to the fruit water supply during this stage of development. The modelled fruit water balance was dominated by transpiration, with net water loss under high vapour pressure deficit (Da) conditions in California, but a net gain under cooler New Zealand conditions. Direct measurement of pedicel sap flow under controlled conditions confirmed inward flows in both the phloem and xylem under conditions of both low and high Da. Phloem flows were required for growth, with gradual recovery after a step increase in Da. Xylem flows alone were unable to support growth, but did supply transpiration and were responsive to Da-induced pressure fluctuations. The results suggest that the shrivel disorder was a consequence of a high fruit transpiration rate, and that the perception of complete loss or reversal of inward xylem flows in ripening fruits should be re-examined. PMID:22155631

  15. Investigating surface topology and cyclic-RGD peptide functionalization on vascular endothelialization.

    PubMed

    McNichols, Colton; Wilkins, Justin; Kubota, Atsutoshi; Shiu, Yan T; Aouadi, Samir M; Kohli, Punit

    2014-02-01

    The advantages of endothelialization of a stent surface in comparison with the bare metal and drug-eluting stents used today include reduced late-stent restenosis and in-stent thrombosis. In this article, we study the effect of surface topology and functionalization of tantalum (Ta) with cyclic-(arginine-glycine-aspartic acid-d-phenylalanine-lysine) (cRGDfK) on the attachment, spreading, and growth of vascular endothelial cells. Self-assembled nanodimpling on Ta surfaces was performed using a one-step electropolishing technique. Next, cRGDfK was covalently bonded onto the surface using silane chemistry. Our results suggest that nanotexturing alone was sufficient to enhance cell spreading, but the combination of a nanodimpled surfaces along with the cRGDfK peptide may produce a better endothelialization coating on the surface in terms of higher cell density, better cell spreading, and more cell-cell interactions, when compared to using cRGDfK peptide functionalization alone or nanotexturing alone. We believe that future research should look into how to implement both modifications (topographic and chemical modifications) to optimize the stent surface for endothelialization. PMID:23505215

  16. Localization and function of KLF4 in cytoplasm of vascular smooth muscle cell

    SciTech Connect

    Liu, Yan; Zheng, Bin; Zhang, Xin-hua; Nie, Chan-juan; Li, Yong-hui; Wen, Jin-kun

    2013-06-28

    Highlights: •PDGF-BB prompts the translocation of KLF4 to the cytoplasm. •PDGF-BB promotes interaction between KLF4 and actin in the cytoplasm. •Phosphorylation and SUMOylation of KLF4 participates in regulation of cytoskeletal organization. •KLF4 regulates cytoskeleton by promoting the expression of contraction-associated genes. -- Abstract: The Krüppel-like factor 4 is a DNA-binding transcriptional regulator that regulates a diverse array of cellular processes, including development, differentiation, proliferation, and apoptosis. The previous studies about KLF4 functions mainly focused on its role as a transcription factor, its functions in the cytoplasm are still unknown. In this study, we found that PDGF-BB could prompt the translocation of KLF4 to the cytoplasm through CRM1-mediated nuclear export pathway in vascular smooth muscle cells (VSMCs) and increased the interaction of KLF4 with actin in the cytoplasm. Further study showed that both KLF4 phosphorylation and SUMOylation induced by PDGF-BB participates in regulation of cytoskeletal organization by stabilizing the actin cytoskeleton in VSMCs. In conclusion, these results identify that KLF4 participates in the cytoskeletal organization by stabilizing cytoskeleton in the cytoplasm of VSMCs.

  17. Differentiation and functional connection of vascular elements in compatible and incompatible pear/quince internode micrografts.

    PubMed

    Espen, Luca; Cocucci, Maurizio; Sacchi, Gian Attilio

    2005-11-01

    Micrografts of internodes excised from in vitro grown pear plants (Pyrus communis L. cv. 'Bosc' (B) and cv. 'Butirra Hardy' (BH)) and quince (Cydonia oblonga Mill. East Malling clone C (EMC)), were cultured aseptically to test the effectiveness of their functional vascular reconnection in relation to incompatibility-compatibility relationships that these genotypes exhibit in the field. The incompatible heterograft (B/EMC) showed a marked delay in internode cohesion compared with the autografts (both B/B and BH/BH) and the compatible heterograft (BH/EMC). Even when fused, the translocation of [14C]-sorbitol from upper to lower internode was lower in B/EMC micrografts than in the other combinations. Epifluorescence studies performed with carboxyfluorescin, a specific phloem probe, indicated that the limited translocation was caused by a delay in the establishment of functional phloem continuity between the two internodes. In the B/EMC combination, new differentiated tracheary elements (TE) in the parenchyma tissue at the graft interface between the two internodes were not detected until 30 days after grafting, whereas in the BH/EMC heterograft and both autografts, new xylem connections appeared to cross the interface 20 days after grafting. Immunohistochemical detection (terminal nick-end labeling assay) of the number of cells undergoing nuclear DNA fragmentation at the graft interface confirmed that the limited and delayed TE differentiation in B/EMC heterografts was associated with a decrease in the activity of programmed cell death processes involved in the differentiation of TE. PMID:16105809

  18. Investigating Surface Topology and Cyclic-RGD Peptide functionalization on Vascular Endothelialization

    PubMed Central

    McNichols, Colton; Wilkins, Justin; Kubota, Atsu; Shiu, Yan T.; Aouadi, Samir M.; Kohli, Punit

    2013-01-01

    The advantages of endothelialization of a stent surface in comparison with the bare metal and drug eluting stents used today include reduced late-stent restenosis and in-stent thrombosis. In this paper, we study the effect of surface topology and functionalization of tantalum (Ta) with cyclic-(arginine-glycine-aspartic acid-D-phenylalanine-lysine (cRGDfK)) on the attachment, spreading, and growth of vascular endothelial cells. Self-assembled nano-dimpling on Ta surfaces was performed using a one-step electropolishing technique. Next, cRGDfK was covalently bonded onto the surface using silane chemistry. Our results suggest that nano-texturing alone was sufficient to enhance cell spreading, but the combination of a nano-dimpled surfaces along with the cRGDfK peptide may produce a better endothelialization coating on the surface in terms of higher cell density, better cell spreading, and more cell-cell interactions, when compared to using cRGDfK peptide functionalization alone or nano-texturing alone. We believe that future research should look into how to implement both modifications (topographic and chemical modifications) to optimize the stent surface for endothelialization. PMID:23505215

  19. Influence of Vascular Variant of the Posterior Cerebral Artery (PCA) on Cerebral Blood Flow, Vascular Response to CO2 and Static Functional Connectivity

    PubMed Central

    Emmert, Kirsten; Zöller, Daniela; Preti, Maria Giulia; Van De Ville, Dimitri; Giannakopoulos, Panteleimon; Haller, Sven

    2016-01-01

    Introduction The fetal origin of the posterior cerebral artery (fPCA) is a frequent vascular variant in 11–29% of the population. For the fPCA, blood flow in the PCA originates from the anterior instead of the posterior circulation. We tested whether this blood supply variant impacts the cerebral blood flow assessed by arterial spin labeling (ASL), cerebrovascular reserve as well as resting-state static functional connectivity (sFC) in the sense of a systematic confound. Methods The study included 385 healthy, elderly subjects (mean age: 74.18 years [range: 68.9–90.4]; 243 female). Participants were classified into normal vascular supply (n = 296, 76.88%), right fetal origin (n = 23, 5.97%), left fetal origin (n = 16, 4.16%), bilateral fetal origin (n = 4, 1.04%), and intermediate (n = 46, 11.95%, excluded from further analysis) groups. ASL-derived relative cerebral blood flow (relCBF) maps and cerebrovascular reserve (CVR) maps derived from a CO2 challenge with blocks of 7% CO2 were compared. Additionally, sFC between 90 regions of interest (ROIs) was compared between the groups. Results CVR was significantly reduced in subjects with ipsilateral fPCA, most prominently in the temporal lobe. ASL yielded a non-significant trend towards reduced relCBF in bilateral posterior watershed areas. In contrast, conventional atlas-based sFC did not differ between groups. Conclusions In conclusion, fPCA presence may bias the assessment of cerebrovascular reserve by reducing the response to CO2. In contrast, its effect on ASL-assessed baseline perfusion was marginal. Moreover, fPCA presence did not systematically impact resting-state sFC. Taken together, this data implies that perfusion variables should take into account the vascularization patterns. PMID:27532633

  20. Combined Effects of Gamma Radiation and High Dietary Iron on Peripheral Leukocyte Distribution and Function

    NASA Technical Reports Server (NTRS)

    Crucian, Brian E.; Morgan, Jennifer L. L.; Quiriarte, Heather A.; Sams, Clarence F.; Smith, Scott M.; Zwart, Sara R.

    2012-01-01

    Both radiation and increased iron stores can independently increase oxidative damage, resulting in protein, lipid and DNA oxidation. Oxidative stress increases the risk of many health problems including cancer, cataracts, and heart disease. This study, a subset of a larger interdisciplinary investigation of the combined effect of iron overload on sensitivity to radiation injury, monitored immune parameters in the peripheral blood of rats subjected to gamma radiation, high dietary iron or both. Specific immune measures consisted of: (1) peripheral leukocyte distribution, (2) plasma cytokine levels and (3) cytokine production profiles following whole blood mitogenic stimulation

  1. Detrimental effects of high-fat diet loading on vascular endothelial function and therapeutic efficacy of ezetimibe and statins in patients with type 2 diabetes.

    PubMed

    Kurozumi, Akira; Okada, Yosuke; Mori, Hiroko; Kobayashi, Takuya; Masuda, Daisaku; Yamashita, Shizuya; Tanaka, Yoshiya

    2016-05-31

    Several recent reports from large clinical trials have described the role of postprandial hyperlipidemia in the onset of atherosclerosis. In this pilot study, the effects of postprandial lipid abnormalities induced by high-fat diet loading on vascular endothelial function in type 2 diabetes were investigated and the effects of ezetimibe and statins on endothelial function were compared. In 20 patients in Study 1, peripheral arterial tonometry tests were performed before and 4h after loading to measure the reactive hyperemia index (RHI). In Study 2, the same patients were randomly allocated to ezetimibe or rosuvastatin. After 1 week of treatment, loading tests were conducted in the same manner. In Study 1, the RHI decreased from 1.86 to 1.60. There were no significant correlations between changes in RHI and the area under the curve (AUC) or coefficient of variation (CV) of each metabolic marker. In Study 2, ezetimibe treatment resulted in a significant improvement in RHI. The two drugs had comparable effects on changes in AUC. There were no significant correlations between changes in RHI and changes in AUC or changes in CV. When age, sex, drug, hemoglobin A1c, and changes in each lipid were evaluated as independent variables with RHI improvement as the dependent variable, drug differences were found to exert the greatest effect on RHI improvement using a stepwise procedure. The results of this study suggest that the progression of atherosclerosis is due to abnormalities in postprandial lipid metabolism and that ezetimibe can potentially inhibit the aggravation of vascular endothelial dysfunction after high-fat diet loading. PMID:26842592

  2. Pioglitazone treatment increases COX-2-derived prostacyclin production and reduces oxidative stress in hypertensive rats: role in vascular function

    PubMed Central

    Hernanz, Raquel; Martín, Ángela; Pérez-Girón, Jose V; Palacios, Roberto; Briones, Ana M; Miguel, Marta; Salaices, Mercedes; Alonso, María J

    2012-01-01

    BACKGROUND AND PURPOSE PPARγ agonists, glitazones, have cardioprotective and anti-inflammatory actions associated with gene transcription interference. In this study, we determined whether chronic treatment of adult spontaneously hypertensive rats (SHR) with pioglitazone alters BP and vascular structure and function, and the possible mechanisms involved. EXPERIMENTAL APPROACH Mesenteric resistance arteries from untreated or pioglitazone-treated (2.5 mg·kg−1·day−1, 28 days) SHR and normotensive [Wistar Kyoto (WKY)] rats were used. Vascular structure was studied by pressure myography, vascular function by wire myography, protein expression by Western blot and immunohistochemistry, mRNA levels by RT-PCR, prostanoid levels by commercial kits and reactive oxygen species (ROS) production by dihydroethidium-emitted fluorescence. KEY RESULTS In SHR, pioglitazone did not modify either BP or vascular structural and mechanical alterations or phenylephrine-induced contraction, but it increased vascular COX-2 levels, prostacyclin (PGI2) production and the inhibitory effects of NS 398, SQ 29,548 and tranylcypromine on phenylephrine responses. The contractile phase of the iloprost response, which was reduced by SQ 29,548, was greater in pioglitazone-treated and pioglitazone-untreated SHR than WKY. In addition, pioglitazone abolished the increased vascular ROS production, NOX-1 levels and the inhibitory effect of apocynin and allopurinol on phenylephrine contraction, whereas it did not modify eNOS expression but restored the potentiating effect of N-nitro-L-arginine methyl ester on phenylephrine responses. CONCLUSIONS AND IMPLICATIONS Although pioglitazone did not reduce BP in SHR, it increased COX-2-derived PGI2 production, reduced oxidative stress, and increased NO bioavailability, which are all involved in vasoconstrictor responses in resistance arteries. These effects would contribute to the cardioprotective effect of glitazones reported in several pathologies. PMID

  3. Vascular Endothelial Growth Factor Prevents Apoptosis and Preserves Contractile Function in Hypertrophied Infant Heart

    PubMed Central

    Friehs, Ingeborg; Barillas, Rodrigo; Vasilyev, Nikolay V.; Roy, Nathalie; McGowan, Francis X.; del Nido, Pedro J.

    2012-01-01

    Background Cardiac hypertrophy is an adaptive response to increased workload that, if unrelieved, leads to heart failure. It has been reported that cardiomyocyte apoptosis contributes to failure, and that vascular endothelial growth factor (VEGF) treatment of hypertrophied myocardium increases capillary density and improves myocardial perfusion. In this study we hypothesized that VEGF treatment reduces cardiomyocyte apoptosis and thereby preserves myocardial contractile function. Methods and Results Newborn rabbits underwent aortic banding. At 4 and 6 weeks of age, hypertrophied animals were treated with intrapericardial administration of recombinant VEGF protein. Three groups of animals were investigated: age-matched controls (C), untreated hypertrophied (H), and VEGF-treated hypertrophied hearts (T). Cardiomyocyte apoptosis was determined by TUNEL staining and PARP cleavage (immunoblotting of nuclear extracts) and cardiac function by transthoracic echocardiography. Death attributable to severe heart failure occurred in 14 of 43 untreated and 2 of 29 VEGF-treated animals (P<0.01). TUNEL-positive cardiomyocyte nuclei (n/1000 nuclei) were significantly increased in untreated hearts at 5 weeks (H: 10±1.8 versus T: 3±0.7) and at 7 weeks (H: 13±3.6 versus T: 5±1.5; P<0.05). Increased apoptosis in untreated hypertrophy was also confirmed by the presence of PARP cleavage (H: 74±7 versus T: 41±4 arbitrary densitometry units; P<0.05). VEGF treatment preserved left ventricular mass, prevented dilation (T: 1.01±0.06 versus H: 0.77±0.07; P<0.05), and preserved contractility indices compared with untreated hearts. Conclusions Lack of adaptive capillary growth impairs myocardial perfusion and substrate delivery in hypertrophying myocardium. VEGF treatment reduces myocardial apoptosis and prolongs survival in a model of severe progressive left ventricular hypertrophy. Promoting capillary growth with VEGF reduces apoptosis, preserves myocardial contractile function, and

  4. Agonist-mediated changes in intracellular pH: role in vascular smooth muscle cell function

    SciTech Connect

    Berk, B.C.; Canessa, M.; Vallega, G.; Alexander, R.W.

    1988-01-01

    Changes in intracellular pH (pHi) are likely to play an important role in regulation of vascular smooth muscle cell (VSMC) function. In most blood vessels, acidification is associated with decreased contractile tone and alkalinization with increased tone. However, the nature of agonist-mediated alterations in pHi and the role of pHi in other VSMC responses has been little studied. We have used the pH sensitive dye, BCECF, to study pHi in cultured rat aortic VSMC. Basal pHi at 37 degrees C in physiologic saline buffer (pH 7.3) was 7.08 in suspended VSMC and 7.26 in substrate-attached VSMC. An amiloride-sensitive Na+/H+ exchanger mediated pHi recovery following an acid load. Angiotensin II- and platelet-derived growth factor typified one class of VSMC agonists, causing an initial transient (less than 5 min) acidification followed by a sustained (greater than 20 min) alkalinization. The acidification phase was associated with increased Ca2+ mobilization as demonstrated by increases in intracellular Ca2+ and 45Ca2+ efflux. The alkalinization was associated with Na+ influx and H+ efflux consistent with Na+/H+ exchange. Epidermal growth factor and phorbol esters typified another class of agonists which stimulated only a sustained alkalinization. Alterations in regulation of VSMC pHi may play an important role in VSMC hypertrophy and/or proliferation as suggested by the finding of increased cell growth and Na+/H+ exchange in spontaneously hypertensive rat VSMC compared to Wistar-Kyoto VSMC. Although no functional correlate for initial acidification has been identified, cytoplasmic alkalinization appears to be required for the sustained formation of diacylglycerol following angiotensin II stimulation. These findings suggest that alterations in pHi may regulate several VSMC functions such as agonist-mediated signal transduction, excitation-response coupling, and growth.

  5. Right ventricular diastolic function in dialysis patients could be affected by vascular access.

    PubMed

    Di Lullo, Luca; Floccari, Fulvio; Polito, Pasquale

    2011-01-01

    Tricuspid annular plane excursion (TAPSE) measurement in echocardiography is a measure of heart diastolic distensibility: a low TAPSE indicates reduced ventricular distensibility leading to diastolic dysfunction. It is a good prognostic index for cardiac mortality risk in congestive heart failure patients, adding significant prognostic information to the NYHA clinical classification. Our study was designed to evaluate the effect of a single hemodialysis (HD) session on diastolic function and TAPSE, focusing on the effects of vascular access typology. Twenty chronically uremic patients (age 51 ± 10 years, dialytic age 24 ± 8 months), without overt heart disease, underwent conventional two-dimensional and Doppler echocardiography immediately before starting and 15 min after ending a mid-week HD session. Ten patients had distal radiocephalic arterovenous fistula (AVF), and 10 had permanent central venous catheters (CVC). The amount of fluid removed by HD was 2,706 ± 1,047 g/session. HD led to a reduction in TAPSE, left ventricle end-diastole volume, left ventricle end-systole volume, right ventricle end-diastole diameter, peak early transmitral flow velocity, and the ratio of early to late Doppler velocities of diastolic mitral flow. AVF patients showed greater right ventricle diameters versus CVC patients, while TAPSE appeared higher in the latter. Only the AVF patient group showed TAPSE values <15 mm. Our data confirm the effects of terminal uremia on right ventricle function (chamber dilation, impaired diastolic function), showing that these abnormalities are more frequent in AVF patients as opposed to CVC patients. It is reasonable to explain these clinical features as the effect of preload increase operated by AVF. PMID:21196771

  6. The effects of temperature on peripheral neuronal function in eurythermal and stenothermal crustaceans.

    PubMed

    Young, John S; Peck, Lloyd S; Matheson, Thomas

    2006-05-01

    To determine whether neuronal function in Antarctic crustaceans is adapted to the low and narrow range of temperatures at which these animals live, we have compared conduction velocities in the peripheral nervous systems of two temperate species, the decapod Carcinus maenas and the isopod Ligia oceanica, and two Antarctic species, the isopod Glyptonotus antarcticus and the amphipod Paraceradocus gibber. Neuronal conduction velocity differs among the species in the order C. maenas > G. antarcticus > P. gibber > L. oceanica. When measured at the normal environmental temperatures characteristic of each species, conduction velocity of the Antarctic peracarid P. gibber is greater than that of its similar sized temperate relative L. oceanica, demonstrating complete thermal compensation. The temperate decapod C. maenas has a higher thermal dependence of neuronal conduction velocity than either of the Antarctic species, G. antarcticus and P. gibber, but the temperate L. oceanica does not. These data, when collated with published values, indicate that peracarid crustaceans (L. oceanica, G. antarcticus and P. gibber) have lower neuronal conduction velocities and a lower thermal dependence of neuronal conduction velocity than do other arthropods, irrespective of habitat. There is a linear dependence of conduction velocity on temperature down to -1.8 degrees C in all three species. Our data extend by more than 10 degrees the lower range of temperatures at which conduction velocities have been tested systematically in previous studies. The upper thermal block of neuronal conduction is similar in C. maenas, G. antarcticus, P. gibber and L. oceanica at 24.5, 19.5, 21.5 and 19.5 degrees C, respectively. This suggests that failure to conduct action potentials is not what determines the mortality of Antarctic invertebrates at approximately 10 degrees C. The excitability of axons in the leg nerve of G. antarcticus is not affected by temperatures ranging from -1.8 to +18 degrees C

  7. Endothelin B receptor contribution to peripheral microvascular function in women with polycystic ovary syndrome

    PubMed Central

    Wenner, Megan M; Taylor, Hugh S; Stachenfeld, Nina S

    2011-01-01

    Abstract Endothelin-1 is elevated in women with polycystic ovary syndrome (PCOS), and may play a role in the endothelial dysfunction associated with PCOS. Endothelin-1 binds two receptor subtypes, endothelin A (ET-A) and endothelin B (ET-B). We hypothesized that ET-A mediates vasoconstriction in the cutaneous microvasculature in women with and without PCOS. We further hypothesized that while the ET-B receptors mediate vasodilatation in both groups of women, this response would be blunted in women with PCOS. During local skin warming, we used laser Doppler flowmetry combined with intradermal microdialysis to measure skin blood flow (SkBF) during graded ET-A (BQ-123) and ET-B (BQ-788) antagonist infusions in women with (n = 6) and without (n = 8) PCOS. In both groups, SkBF increased during local heating. The percentage of maximal SkBF–[BQ123] sigmoidal dose–response curve indicated a vasodilatory response as the concentration of the antagonist increased (Hill slope 4.96 ± 4.77, 4.74 ± 5.01; logED50 2.53 ± 0.09, 2.49 ± 0.09 nm, for PCOS and Control, respectively). In contrast, the % max SkBF–[BQ788] curve indicated a vasoconstrictive response (Hill slope –4.69 ± 3.85, –4.03 ± 3.85; logED50, 2.56 ± 0.09, 2.41 ± 0.12 nm, in PCOS and Control). Moreover, the SkBF–[BQ788] curve shifted to the right in women with PCOS, suggesting attenuated ET-B receptor mediated vasodilatation during local skin warming compared to Controls. Thus, the endothelium located ET-B receptors function similarly in women with and without PCOS, although with blunted responsiveness in women with PCOS. Our studies suggest that the lower ET-B receptor responsiveness associated with PCOS may reflect lower endothelial-mediated vasodilatation independent of generally lower vascular reactivity. PMID:21825025

  8. Chloride ion currents contribute functionally to norepinephrine-induced vascular contraction.

    PubMed

    Lamb, F S; Barna, T J

    1998-07-01

    Norepinephrine (NE) increases Cl- efflux from vascular smooth muscle (VSM) cells. An increase in Cl- conductance produces membrane depolarization. We hypothesized that if Cl- currents are important for agonist-induced depolarization, then interfering with cellular Cl- handling should alter contractility. Isometric contraction of rat aortic rings was studied in a bicarbonate buffer. Substitution of extracellular Cl- with 130 mM methanesulfonate (MS; 8 mM Cl-) did not cause contraction. NE- and serotonin-induced contractions were potentiated in this low-Cl- buffer, whereas responses to K+, BAY K 8644, or NE in the absence of Ca2+ were unaltered. Substitution of Cl- with I- or Br- suppressed responses to NE. Inhibition of Cl- transport with bumetanide (10(-5) M) or bicarbonate-free conditions (10 mM HEPES) inhibited NE- but not KCl-induced contraction. The Cl--channel blockers DIDS (10(-3) M), anthracene-9-carboxylic acid (10(-3) M), and niflumic acid (10(-5) M) all inhibited NE-induced contraction, whereas tamoxifen (10(-5) M) did not. Finally, disruption of sarcoplasmic reticular function with cyclopiazonic acid (10(-7) M) or ryanodine (10(-5) M) prevented the increase in the peak response to NE produced by low-Cl- buffer. We conclude that a Cl- current with a permeability sequence of I- > Br- > Cl- > MS is critical to agonist-induced contraction of VSM. PMID:9688908

  9. Non-invasive functional imaging of Cerebral Blood Volume with Vascular-Space-Occupancy (VASO) MRI

    PubMed Central

    Lu, Hanzhang; Hua, Jun; van Zijl, Peter C.M.

    2013-01-01

    Functional MRI (fMRI) based on changes in cerebral blood volume (CBV) can directly probe vasodilatation and vasoconstriction during brain activation or physiologic challenges, and can provide important insights into the mechanism of Blood-Oxygenation-Level-Dependent (BOLD) signal changes. At present, the most widely used CBV fMRI technique in humans is called Vascular-Space-Occupancy (VASO) MRI and this article provides a technical review of this method. VASO MRI utilizes T1 differences between blood and tissue to distinguish these two compartments within a voxel and uses blood-nulling inversion recovery sequence to yield an MR signal proportional to 1-CBV. As such, vasodilatation will result in a VASO signal decrease and vasoconstriction will have the reverse effect. The VASO technique can be performed dynamically with a temporal resolution comparable to several other fMRI methods such as BOLD or Arterial-Spin-Labeling (ASL), and is particularly powerful when conducted in conjunction with these complementary techniques. The pulse sequence and imaging parameters of VASO can be optimized such that the signal change is predominantly of CBV origin, but careful considerations should be taken to minimize other contributions, such as those from the BOLD effect, CBF, and CSF. Sensitivity of the VASO technique remains to be the primary disadvantage when compared to BOLD, but this technique is increasingly demonstrating utility in neuroscientific and clinical applications. PMID:23355392

  10. Nitinol-based Nanotubular and Nanowell Coatings for the Modulation of Human Vascular Cell Functions

    NASA Astrophysics Data System (ADS)

    Lee, Phin Peng

    Current approaches to reducing restenosis do not balance the reduction of vascular smooth muscle cell proliferation with the increase in the healing of the endothelium. Here, I present my study on the synthesis and characterization of a nanotubular coating on Nitinol substrates. I found that the coating demonstrated 'pro-healing' properties by increasing primary human aortic endothelial cell spreading, migration and collagen and elastin production. Certain cellular functions such as collagen and elastin production were also found to be affected by changes in nanotube diameter. The coating also reduced the proliferation and mRNA expression of collagen I and MMP2 for primary human aortic smooth muscle cells. I will also demonstrate the synthesis of a nanowell coating on Nitinol stents as well as an additional poly(lactic-co-glycolic acid) coating on top of the nanowells that has the potential for controlling drug release. These findings demonstrate the potential for the coatings to aid in the prevention of restenosis and sets up future explorations of ex vivo and in vivo studies.

  11. Circulating HIV-Specific Interleukin-21(+)CD4(+) T Cells Represent Peripheral Tfh Cells with Antigen-Dependent Helper Functions.

    PubMed

    Schultz, Bruce T; Teigler, Jeffrey E; Pissani, Franco; Oster, Alexander F; Kranias, Gregory; Alter, Galit; Marovich, Mary; Eller, Michael A; Dittmer, Ulf; Robb, Merlin L; Kim, Jerome H; Michael, Nelson L; Bolton, Diane; Streeck, Hendrik

    2016-01-19

    A central effort in HIV vaccine development is to generate protective broadly neutralizing antibodies, a process dependent on T follicular helper (Tfh) cells. The feasibility of using peripheral blood counterparts of lymph node Tfh cells to assess the immune response and the influence of viral and vaccine antigens on their helper functions remain obscure. We assessed circulating HIV-specific IL-21(+)CD4(+) T cells and showed transcriptional and phenotypic similarities to lymphoid Tfh cells, and hence representing peripheral Tfh (pTfh) cells. pTfh cells were functionally active and B cell helper quality differed depending on antigen specificity. Furthermore, we found higher frequency of pTfh cells in peripheral blood mononuclear cell specimens from the ALVAC+AIDSVAX (RV144) HIV vaccine trial associated with protective antibody responses compared to the non-protective DNA+Ad5 vaccine trial. Together, we identify IL-21(+)CD4(+) T cells as pTfh cells, implicating them as key populations in the generation of vaccine-evoked antibody responses. PMID:26795249

  12. A divergent route to core- and peripherally functionalized diazacoronenes that act as colorimetric and fluorescence proton sensors

    DOE PAGESBeta

    He, Bo; Dai, Jing; Zherebetskyy, Danylo; Chen, Teresa L.; Zhang, Benjamin A.; Teat, Simon J.; Zhang, Qichun; Wang, Linwang; Liu, Yi

    2015-03-31

    Combining core annulation and peripheral group modification, we have demonstrated a divergent synthesis of a family of highly functionalized coronene derivatives from a readily accessible dichlorodiazaperylene intermediate. Various reactions, such as aromatic nucleophilic substitution, Kumada coupling and Suzuki coupling proceed effectively on α-positions of the pyridine sites, giving rise to alkoxy, thioalkyl, alkyl or aryl substituted polycyclic aromatic hydrocarbons. In addition to peripheral group modulation, the aromatic core structures can be altered by annulation with thiophene or benzene ring systems. Corresponding single crystal X-ray diffraction and optical studies indicate that the heteroatom linkages not only impact the solid state packing,more » but also significantly influence the optoelectronic properties. Moreover, these azacoronene derivatives display significant acid-induced spectroscopic changes, suggesting their great potential as colorimetric and fluorescence proton sensors.« less

  13. A divergent route to core- and peripherally functionalized diazacoronenes that act as colorimetric and fluorescence proton sensors

    SciTech Connect

    He, Bo; Dai, Jing; Zherebetskyy, Danylo; Chen, Teresa L.; Zhang, Benjamin A.; Teat, Simon J.; Zhang, Qichun; Wang, Linwang; Liu, Yi

    2015-03-31

    Combining core annulation and peripheral group modification, we have demonstrated a divergent synthesis of a family of highly functionalized coronene derivatives from a readily accessible dichlorodiazaperylene intermediate. Various reactions, such as aromatic nucleophilic substitution, Kumada coupling and Suzuki coupling proceed effectively on α-positions of the pyridine sites, giving rise to alkoxy, thioalkyl, alkyl or aryl substituted polycyclic aromatic hydrocarbons. In addition to peripheral group modulation, the aromatic core structures can be altered by annulation with thiophene or benzene ring systems. Corresponding single crystal X-ray diffraction and optical studies indicate that the heteroatom linkages not only impact the solid state packing, but also significantly influence the optoelectronic properties. Moreover, these azacoronene derivatives display significant acid-induced spectroscopic changes, suggesting their great potential as colorimetric and fluorescence proton sensors.

  14. Differential Effects of Hormone Therapy on Serotonin, Vascular Function and Mood in the KEEPS

    PubMed Central

    Raz, Limor; Hunter, Larry; Dowling, N. Maritza; Wharton, Whitney; Gleason, Carey; Jayachandran, Muthuvel; Anderson, Layne; Asthana, Sanjay; Miller, Virginia

    2016-01-01

    Background Serotonin (5-hydroxytryptamine, 5-HT) is modulated by sex steroid hormones and affects vascular function and mood. In the Kronos Early Estrogen Prevention Cognitive and Affective Ancillary Study (KEEPS-Cog), women randomized to oral conjugated equine estrogens (oCEE) showed greater benefit on affective mood states than women randomized to transdermal 17β-estradiol (tE2) or placebo (PL). This study examined the effect of these treatments on the platelet content of 5-HT as a surrogate measure of 5-HT synthesis and uptake in the brain. Methods The following were measured in a subset (n = 79) of women enrolled in KEEPS-Cog: 5-HT by ELISA, carotid intima-medial thickness (CIMT) by ultrasound, endothelial function by reactive hyperemia index (RHI), and self-reported symptoms of affective mood states by the Profile of Mood States (POMS) questionnaire. Results Mean platelet content of 5-HT increased by 107.0%, 84.5% and 39.8%, in tE2, oCEE and PL groups, respectively. Platelet 5-HT positively correlated with estrone in the oCEE group and with 17β- estradiol in the tE2 group. Platelet 5-HT showed a positive association with RHI, but not CIMT, in the PL and oCEE groups. Reduction in mood scores for depression-dejection and anger-hostility associated with elevations in platelet 5-HT only in the oCEE group (r = −0.5, p = 0.02). Conclusions Effects of oCEE compared to tE2 on RHI and mood may be related to mechanisms involving platelet, and perhaps neuronal, uptake and release of 5-HT and reflect conversion of estrone to bioavailable 17β- estradiol in platelets and the brain. PMID:26652904

  15. Deletion of thioredoxin-interacting protein preserves retinal neuronal function by preventing inflammation and vascular injury

    PubMed Central

    El-Azab, M F; Baldowski, B R B; Mysona, B A; Shanab, A Y; Mohamed, I N; Abdelsaid, M A; Matragoon, S; Bollinger, K E; Saul, A; El-Remessy, A B

    2014-01-01

    BACKGROUND AND PURPOSE Retinal neurodegeneration is an early and critical event in several diseases associated with blindness. Clinically, therapies that target neurodegeneration fail. We aimed to elucidate the multiple roles by which thioredoxin-interacting protein (TXNIP) contributes to initial and sustained retinal neurodegeneration. EXPERIMENTAL APPROACH Neurotoxicity was induced by intravitreal injection of NMDA into wild-type (WT) and TXNIP-knockout (TKO) mice. The expression of apoptotic and inflammatory markers was assessed by immunohistochemistry, elisa and Western blot. Microvascular degeneration was assessed by periodic acid-Schiff and haematoxylin staining and retinal function by electroretinogram. KEY RESULTS NMDA induced early (1 day) and significant retinal PARP activation, a threefold increase in TUNEL-positive nuclei and 40% neuronal loss in ganglion cell layer (GCL); and vascular permeability in WT but not TKO mice. NMDA induced glial activation, expression of TNF-α and IL-1β that co-localized with Müller cells in WT but not TKO mice. In parallel, NMDA triggered the expression of NOD-like receptor protein (NLRP3), activation of caspase-1, and release of IL-1β and TNF-α in primary WT but not TKO Müller cultures. After 14 days, NMDA induced 1.9-fold microvascular degeneration, 60% neuronal loss in GCL and increased TUNEL-labelled cells in the GCL and inner nuclear layer in WT but not TKO mice. Electroretinogram analysis showed more significant reductions in b-wave amplitudes in WT than in TKO mice. CONCLUSION AND IMPLICATIONS Targeting TXNIP expression prevented early retinal ganglion cell death, glial activation, retinal inflammation and secondary neuro/microvascular degeneration and preserved retinal function. TXNIP is a promising new therapeutic target for retinal neurodegenerative diseases. PMID:24283717

  16. Augmented EGF receptor tyrosine kinase activity impairs vascular function by NADPH oxidase-dependent mechanism in type 2 diabetic mouse.

    PubMed

    Kassan, Modar; Ait-Aissa, Karima; Ali, Maha; Trebak, Mohamed; Matrougui, Khalid

    2015-10-01

    We previously determined that augmented EGFR tyrosine kinase (EGFRtk) impairs vascular function in type 2 diabetic mouse (TD2). Here we determined that EGFRtk causes vascular dysfunction through NADPH oxidase activity in TD2. Mesenteric resistance arteries (MRA) from C57/BL6 and db-/db- mice were mounted in a wired myograph and pre-incubated for 1h with either EGFRtk inhibitor (AG1478) or exogenous EGF. The inhibition of EGFRtk did not affect the contractile response to phenylephrine-(PE) and thromboxane-(U46619) or endothelium-dependent relaxation (EDR) to acetylcholine in MRA from control group. However, in TD2 mice, AG1478 reduced the contractile response to U46619, improved vasodilatation and reduced p22phox-NADPH expression, but had no effect on the contractile response to PE. The incubation of MRA with exogenous EGF potentiated the contractile response to PE in MRA from control and diabetic mice. However, EGF impaired the EDR and potentiated the vasoconstriction to U46619 only in the control group. Interestingly, NADPH oxidase inhibition in the presence of EGF restored the normal contraction to PE and improved the EDR but had no effect on the potentiated contraction to U46619. Vascular function improvement was associated with the rescue of eNOS and Akt and reduction in phosphorylated Rho-kinase, NOX4 mRNA levels, and NADPH oxidase activity. MRA from p47phox-/- mice incubated with EGF potentiated the contraction to U46619 but had no effect to PE or ACh responses. The present study provides evidence that augmented EGFRtk impairs vascular function by NADPH oxidase-dependent mechanism. Therefore, EGFRtk and oxidative stress should be potential targets to treat vascular dysfunction in TD2. PMID:26036345

  17. A Functional Role for VEGFR1 Expressed in Peripheral Sensory Neurons in Cancer Pain

    PubMed Central

    Selvaraj, Deepitha; Gangadharan, Vijayan; Michalski, Christoph W.; Kurejova, Martina; Stösser, Sebastian; Srivastava, Kshitij; Schweizerhof, Matthias; Waltenberger, Johannes; Ferrara, Napoleone; Heppenstall, Paul; Shibuya, Masabumi; Augustin, Hellmut G.; Kuner, Rohini

    2015-01-01

    Summary Cancer pain is a debilitating disorder and a primary determinant of the poor quality of life. Here, we report a non-vascular role for ligands of the Vascular Endothelial Growth Factor (VEGF) family in cancer pain. Tumor-derived VEGF-A, PLGF-2, and VEGF-B augment pain sensitivity through selective activation of VEGF receptor 1 (VEGFR1) expressed in sensory neurons in human cancer and mouse models. Sensory-neuron-specific genetic deletion/silencing or local or systemic blockade of VEGFR1 prevented tumor-induced nerve remodeling and attenuated cancer pain in diverse mouse models in vivo. These findings identify a therapeutic potential for VEGFR1-modifying drugs in cancer pain and suggest a palliative effect for VEGF/VEGFR1-targeting anti-angiogenic tumor therapies. PMID:26058077

  18. Spatial and Functional Selectivity of Peripheral Nerve Signal Recording With the Transversal Intrafascicular Multichannel Electrode (TIME).

    PubMed

    Badia, Jordi; Raspopovic, Stanisa; Carpaneto, Jacopo; Micera, Silvestro; Navarro, Xavier

    2016-01-01

    The selection of suitable peripheral nerve electrodes for biomedical applications implies a trade-off between invasiveness and selectivity. The optimal design should provide the highest selectivity for targeting a large number of nerve fascicles with the least invasiveness and potential damage to the nerve. The transverse intrafascicular multichannel electrode (TIME), transversally inserted in the peripheral nerve, has been shown to be useful for the selective activation of subsets of axons, both at inter- and intra-fascicular levels, in the small sciatic nerve of the rat. In this study we assessed the capabilities of TIME for the selective recording of neural activity, considering the topographical selectivity and the distinction of neural signals corresponding to different sensory types. Topographical recording selectivity was proved by the differential recording of CNAPs from different subsets of nerve fibers, such as those innervating toes 2 and 4 of the hindpaw of the rat. Neural signals elicited by sensory stimuli applied to the rat paw were successfully recorded. Signal processing allowed distinguishing three different types of sensory stimuli such as tactile, proprioceptive and nociceptive ones with high performance. These findings further support the suitability of TIMEs for neuroprosthetic applications, by exploiting the transversal topographical structure of the peripheral nerves. PMID:26087496

  19. α4-Integrin Antibody Treatment Blocks Monocyte/Macrophage Traffic to, Vascular Cell Adhesion Molecule-1 Expression in, and Pathology of the Dorsal Root Ganglia in an SIV Macaque Model of HIV-Peripheral Neuropathy.

    PubMed

    Lakritz, Jessica R; Thibault, Derek M; Robinson, Jake A; Campbell, Jennifer H; Miller, Andrew D; Williams, Kenneth C; Burdo, Tricia H

    2016-07-01

    Traffic of activated monocytes into the dorsal root ganglia (DRG) is critical for pathology in HIV peripheral neuropathy. We have shown that accumulation of recently recruited (bromodeoxyuridine(+) MAC387(+)) monocytes is associated with severe DRG pathology and loss of intraepidermal nerve fibers in SIV-infected macaques. Herein, we blocked leukocyte traffic by treating animals with natalizumab, which binds to α4-integrins. SIV-infected CD8-depleted macaques treated with natalizumab either early (the day of infection) or late (28 days after infection) were compared with untreated SIV-infected animals sacrificed at similar times. Histopathology showed diminished DRG pathology with natalizumab treatment, including decreased inflammation, neuronophagia, and Nageotte nodules. Natalizumab treatment resulted in a decrease in the number of bromodeoxyuridine(+) (early), MAC387(+) (late), CD68(+) (early and late), and SIVp28(+) (late) macrophages in DRG tissues. The number of CD3(+) T lymphocytes in DRGs was not affected by natalizumab treatment. Vascular cell adhesion molecule 1, an adhesion molecule that mediates leukocyte traffic, was diminished in DRGs of all natalizumab-treated animals. These data show that blocking monocyte, but not T lymphocyte, traffic to the DRG results in decreased inflammation and pathology, supporting a role for monocyte traffic and activation in HIV peripheral neuropathy. PMID:27157989

  20. ACCF/ACR/AIUM/ASE/ASN/ICAVL/SCAI/SCCT/SIR/SVM/SVS 2012 appropriate use criteria for peripheral vascular ultrasound and physiological testing part I: Arterial ultrasound and physiological testing

    PubMed Central

    Mohler, Emile R.; Gornik, Heather L.; Gerhard-Herman, Marie; Misra, Sanjay; Olin, Jeffrey W.; Zierler, R. Eugene

    2015-01-01

    The American College of Cardiology Foundation (ACCF), in partnership with key specialty and subspecialty societies, conducted a review of common clinical scenarios where noninvasive vascular testing (ultrasound and physiological testing) is frequently considered. The indications (clinical scenarios) were derived from common applications or anticipated uses, as well as from current clinical practice guidelines and results of studies examining the implementation of the original appropriate use criteria (AUC). The 159 indications in this document were developed by a diverse writing group and scored by a separate independent technical panel on a scale of 1 to 9, to designate appropriate use (median 7 to 9), uncertain use (median 4 to 6), and inappropriate use (median 1 to 3). A total of 255 indications (with the inclusion of surveillance timeframes) were rated. One hundred and seventeen indications were rated as appropriate, 84 were rated as uncertain, and 54 were rated as inappropriate. The AUC for peripheral vascular disease have the potential to impact physician decision making, healthcare delivery, and reimbursement policy. Furthermore, recognition of uncertain clinical scenarios facilitates identification of areas that would benefit from future research. PMID:22694919

  1. ACCF/ACR/AIUM/ASE/ASN/ICAVL/SCAI/SCCT/SIR/SVM/SVS 2012 Appropriate Use Criteria for Peripheral Vascular Ultrasound and Physiological Testing Part I: Arterial Ultrasound and Physiological Testing

    PubMed Central

    Mohler, Emile R.; Gornik, Heather L.; Gerhard-Herman, Marie; Misra, Sanjay; Olin, Jeffrey W.; Zierler, R. Eugene; Wolk, Michael J.; Mohler, Emile R.; Dixon, Bradley S.; Driver, Vickie R.; Fail, Peter S.; Fazel, Reza; Findeiss, Laura; Fuchs, Richard; Gillespie, John; Hughes, Joseph P.; Jaigobin, Cheryl; Leers, Steven A.; Moore, Colleen; Pellerito, John S.; Robbin, Michelle L.; Shugart, Rita E.; Weaver, Fred A.; White, Christopher J.; Yevzlin, Alexander S.; Wolk, Michael J.; Bailey, Steven R.; Douglas, Pamela S.; Hendel, Robert C.; Kramer, Christopher M.; Min, James K.; Patel, Manesh R.; Shaw, Leslee; Stainback, Raymond F.; Allen, Joseph M.

    2015-01-01

    The American College of Cardiology Foundation (ACCF), in partnership with key specialty and subspecialty societies, conducted a review of common clinical scenarios where noninvasive vascular testing (ultrasound and physiological testing) is frequently considered. The indications (clinical scenarios) were derived from common applications or anticipated uses, as well as from current clinical practice guidelines and results of studies examining the implementation of the original appropriate use criteria (AUC). The 159 indications in this document were developed by a diverse writing group and scored by a separate independent technical panel on a scale of 1 to 9, to designate appropriate use (median 7 to 9), uncertain use (median 4 to 6), and inappropriate use (median 1 to 3). A total of 255 indications (with the inclusion of surveillance timeframes) were rated. One hundred and seventeen indications were rated as appropriate, 84 were rated as uncertain, and 54 were rated as inappropriate. The AUC for peripheral vascular disease have the potential to impact physician decision making, healthcare delivery, and reimbursement policy. Furthermore, recognition of uncertain clinical scenarios facilitates identification of areas that would benefit from future research. PMID:22694840

  2. The Effects of Long-Term Oral Benfotiamine Supplementation on Peripheral Nerve Function and Inflammatory Markers in Patients With Type 1 Diabetes

    PubMed Central

    Fraser, David A.; Diep, Lien M.; Hovden, Inger Anette; Nilsen, Kristian B.; Sveen, Kari Anne; Seljeflot, Ingebjørg; Hanssen, Kristian F.

    2012-01-01

    OBJECTIVE To study the effects of long-term oral benfotiamine supplementation on peripheral nerve function and soluble inflammatory markers in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS The study randomly assigned 67 patients with type 1 diabetes to receive 24-month benfotiamine (300 mg/day) or placebo supplementation. Peripheral nerve function and levels of soluble inflammatory variables were assessed at baseline and at 24 months. RESULTS Fifty-nine patients completed the study. Marked increases in whole-blood concentrations of thiamine and thiamine diphosphate were found in the benfotiamine group (both P < 0.001 vs. placebo). However, no significant differences in changes in peripheral nerve function or soluble inflammatory biomarkers were observed between the groups. CONCLUSIONS Our findings suggest that high-dose benfotiamine (300 mg/day) supplementation over 24 months has no significant effects upon peripheral nerve function or soluble markers of inflammation in patients with type 1 diabetes. PMID:22446172

  3. Atomic resolution view into the structure–function relationships of the human myelin peripheral membrane protein P2

    SciTech Connect

    Ruskamo, Salla; Yadav, Ravi P.; Sharma, Satyan; Lehtimäki, Mari; Laulumaa, Saara; Aggarwal, Shweta; Simons, Mikael; Bürck, Jochen; Ulrich, Anne S.; Juffer, André H.; Kursula, Inari; Kursula, Petri

    2014-01-01

    The structure of the human myelin peripheral membrane protein P2 has been refined at 0.93 Å resolution. In combination with functional experiments in vitro, in vivo and in silico, the fine details of the structure–function relationships in P2 are emerging. P2 is a fatty acid-binding protein expressed in vertebrate peripheral nerve myelin, where it may function in bilayer stacking and lipid transport. P2 binds to phospholipid membranes through its positively charged surface and a hydrophobic tip, and accommodates fatty acids inside its barrel structure. The structure of human P2 refined at the ultrahigh resolution of 0.93 Å allows detailed structural analyses, including the full organization of an internal hydrogen-bonding network. The orientation of the bound fatty-acid carboxyl group is linked to the protonation states of two coordinating arginine residues. An anion-binding site in the portal region is suggested to be relevant for membrane interactions and conformational changes. When bound to membrane multilayers, P2 has a preferred orientation and is stabilized, and the repeat distance indicates a single layer of P2 between membranes. Simulations show the formation of a double bilayer in the presence of P2, and in cultured cells wild-type P2 induces membrane-domain formation. Here, the most accurate structural and functional view to date on P2, a major component of peripheral nerve myelin, is presented, showing how it can interact with two membranes simultaneously while going through conformational changes at its portal region enabling ligand transfer.

  4. Hepatocyte growth factor regulated tyrosine kinase substrate in the peripheral development and function of B-cells

    SciTech Connect

    Nagata, Takayuki; Murata, Kazuko; Murata, Ryo; Sun, Shu-lan; Saito, Yutaro; Yamaga, Shuhei; Tanaka, Nobuyuki; Tamai, Keiichi; Moriya, Kunihiko; Kasai, Noriyuki; Sugamura, Kazuo; Ishii, Naoto

    2014-01-10

    Highlights: •ESCRT-0 protein regulates the development of peripheral B-cells. •BCR expression on cell surface should be controlled by the endosomal-sorting system. •Hrs plays important roles in responsiveness to Ag stimulation in B lymphocytes. -- Abstract: Hepatocyte growth factor (HGF)-regulated tyrosine kinase substrate (Hrs) is a vesicular sorting protein that functions as one of the endosomal-sorting proteins required for transport (ESCRT). Hrs, which binds to ubiquitinated proteins through its ubiquitin-interacting motif (UIM), contributes to the lysosomal transport and degradation of ubiquitinated membrane proteins. However, little is known about the relationship between B-cell functions and ESCRT proteins in vivo. Here we examined the immunological roles of Hrs in B-cell development and functions using B-cell-specific Hrs-deficient (Hrs{sup flox/flox};mb1{sup cre/+}:Hrs-cKO) mice, which were generated using a cre-LoxP recombination system. Hrs deficiency in B-cells significantly reduced T-cell-dependent antibody production in vivo and impaired the proliferation of B-cells treated in vitro with an anti-IgM monoclonal antibody but not with LPS. Although early development of B-cells in the bone marrow was normal in Hrs-cKO mice, there was a significant decrease in the number of the peripheral transitional B-cells and marginal zone B-cells in the spleen of Hrs-cKO mice. These results indicate that Hrs plays important roles during peripheral development and physiological functions of B lymphocytes.

  5. Targeted axonal import (TAxI) peptide delivers functional proteins into spinal cord motor neurons after peripheral administration.

    PubMed

    Sellers, Drew L; Bergen, Jamie M; Johnson, Russell N; Back, Heidi; Ravits, John M; Horner, Philip J; Pun, Suzie H

    2016-03-01

    A significant unmet need in treating neurodegenerative disease is effective methods for delivery of biologic drugs, such as peptides, proteins, or nucleic acids into the central nervous system (CNS). To date, there are no operative technologies for the delivery of macromolecular drugs to the CNS via peripheral administration routes. Using an in vivo phage-display screen, we identify a peptide, targeted axonal import (TAxI), that enriched recombinant bacteriophage accumulation and delivered protein cargo into spinal cord motor neurons after intramuscular injection. In animals with transected peripheral nerve roots, TAxI delivery into motor neurons after peripheral administration was inhibited, suggesting a retrograde axonal transport mechanism for delivery into the CNS. Notably, TAxI-Cre recombinase fusion proteins induced selective recombination and tdTomato-reporter expression in motor neurons after intramuscular injections. Furthermore, TAxI peptide was shown to label motor neurons in the human tissue. The demonstration of a nonviral-mediated delivery of functional proteins into the spinal cord establishes the clinical potential of this technology for minimally invasive administration of CNS-targeted therapeutics. PMID:26888285

  6. Targeted axonal import (TAxI) peptide delivers functional proteins into spinal cord motor neurons after peripheral administration

    PubMed Central

    Sellers, Drew L.; Bergen, Jamie M.; Johnson, Russell N.; Back, Heidi; Ravits, John M.; Horner, Philip J.; Pun, Suzie H.

    2016-01-01

    A significant unmet need in treating neurodegenerative disease is effective methods for delivery of biologic drugs, such as peptides, proteins, or nucleic acids into the central nervous system (CNS). To date, there are no operative technologies for the delivery of macromolecular drugs to the CNS via peripheral administration routes. Using an in vivo phage-display screen, we identify a peptide, targeted axonal import (TAxI), that enriched recombinant bacteriophage accumulation and delivered protein cargo into spinal cord motor neurons after intramuscular injection. In animals with transected peripheral nerve roots, TAxI delivery into motor neurons after peripheral administration was inhibited, suggesting a retrograde axonal transport mechanism for delivery into the CNS. Notably, TAxI-Cre recombinase fusion proteins induced selective recombination and tdTomato-reporter expression in motor neurons after intramuscular injections. Furthermore, TAxI peptide was shown to label motor neurons in the human tissue. The demonstration of a nonviral-mediated delivery of functional proteins into the spinal cord establishes the clinical potential of this technology for minimally invasive administration of CNS-targeted therapeutics. PMID:26888285

  7. Stem cells as a new treatment for peripheral artery disease: hype or hope? The point of view of a vascular surgeon.

    PubMed

    Lehalle, Bertrand

    2015-01-01

    Because many of patients with peripheral arterial disease are not eligible for direct or conventional revascularization procedures, because stem cell therapy is being investigated as to its possible role in the treatment of limb ischemia, there is a need to evaluate this treatment and his true application. On the basis of experimental data, preliminary clinical studies have established the safety and feasibility of stem cells implantation in case of critical limb ischemia. Forthcoming large studies, especially randomized placebo controlled double blind studies, related to the optimal cell type, dosage, administration route, will consolidate this evidence and establish mid and long term effectiveness. PMID:25538058

  8. [INTERRELATION BETWEEN THE PREOPERATIVE MORPHOLOGICAL CHARACTERISTICS OF PERIPHERAL BLOOD AND THE QUALITY OF ENGRAFTMENT OF VASCULARIZED ADIPO-FASCIO-CUTANEOUS FLAPS IN RATS].

    PubMed

    Shchudlo, N A; Shchudlo, M M; Sbrodova, L I

    2016-01-01

    The aim of this work was to determine the interrelation between the preoperative blood counts and the quality of vascularized adipo-fascio-cutaneous flap survival. In 10 adult male Wistar rats, a flap with the area of 18 cm2 was formed on the basis of superficial inferior epigastric artery; after a 90 min ischemic period it was replanted. 12 days after operation the quality of flap survival was assessed with computer-assisted planimetry. It was found that the combination of preoperative leukocyte, thrombocyte, neutrophil and eosinophil counts as well as reactive lymphocyte counts close to the maximal reference values increased the probability of epidermolysis. PMID:27487668

  9. Treadmill Exercise Induced Functional Recovery after Peripheral Nerve Repair Is Associated with Increased Levels of Neurotrophic Factors

    PubMed Central

    Park, Jae-Sung; Höke, Ahmet

    2014-01-01

    Benefits of exercise on nerve regeneration and functional recovery have been reported in both central and peripheral nervous system disease models. However, underlying molecular mechanisms of enhanced regeneration and improved functional outcomes are less understood. We used a peripheral nerve regeneration model that has a good correlation between functional outcomes and number of motor axons that regenerate to evaluate the impact of treadmill exercise. In this model, the median nerve was transected and repaired while the ulnar nerve was transected and prevented from regeneration. Daily treadmill exercise resulted in faster recovery of the forelimb grip function as evaluated by grip power and inverted holding test. Daily exercise also resulted in better regeneration as evaluated by recovery of compound motor action potentials, higher number of axons in the median nerve and larger myofiber size in target muscles. Furthermore, these observations correlated with higher levels of neurotrophic factors, glial derived neurotrophic factor (GDNF), brain derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1), in serum, nerve and muscle suggesting that increase in muscle derived neurotrophic factors may be responsible for improved regeneration. PMID:24618564

  10. Neurophysiological assessment of auditory, peripheral nerve, somatosensory, and visual system functions after developmental exposure to ethanol vapors.

    PubMed

    Boyes, William K; Degn, Laura L; Martin, Sheppard A; Lyke, Danielle F; Hamm, Charles W; Herr, David W

    2014-01-01

    Ethanol-blended gasoline entered the market in response to demand for domestic renewable energy sources, and may result in increased inhalation of ethanol vapors in combination with other volatile gasoline constituents. It is important to understand potential risks of inhalation of ethanol vapors by themselves, and also as a baseline for evaluating the risks of ethanol combined with a complex mixture of hydrocarbon vapors. Because sensory dysfunction has been reported after developmental exposure to ethanol, we evaluated the effects of developmental exposure to ethanol vapors on neurophysiological measures of sensory function as a component of a larger project evaluating developmental ethanol toxicity. Pregnant Long-Evans rats were exposed to target concentrations 0, 5000, 10,000, or 21,000 ppm ethanol vapors for 6.5h/day over GD9-GD20. Sensory evaluations of male offspring began between PND106 and PND128. Peripheral nerve function (compound action potentials, nerve conduction velocity (NCV)), somatosensory (cortical and cerebellar evoked potentials), auditory (brainstem auditory evoked responses), and visual evoked responses were assessed. Visual function assessment included pattern elicited visual evoked potentials (VEPs), VEP contrast sensitivity, and electroretinograms recorded from dark-adapted (scotopic), light-adapted (photopic) flashes, and UV flicker and green flicker. No consistent concentration-related changes were observed for any of the physiological measures. The results show that gestational exposure to ethanol vapor did not result in detectable changes in peripheral nerve, somatosensory, auditory, or visual function when the offspring were assessed as adults. PMID:24607749

  11. Prevention of Hippocampal Neuronal Damage and Cognitive Function Deficits in Vascular Dementia by Dextromethorphan.

    PubMed

    Xu, Xiaofeng; Zhang, Bin; Lu, Kaili; Deng, Jiangshan; Zhao, Fei; Zhao, Bing-Qiao; Zhao, Yuwu

    2016-07-01

    Dextromethorphan (DM) is a non-competitive antagonist of NMDA receptors and a widely used component of cough medicine. Recently, its indication has been extended experimentally to a wide range of disorders including inflammation-mediated central nervous system disorders such as Parkinson disease (PD) and multiple sclerosis (MS). In this study, we investigate whether DM treatment has protective effects on the hippocampal neuron damage induced by bilateral occlusion of the common carotid arteries (two-vessel occlusion [2VO]), an animal model of vascular dementia (VaD). Sprague-Dawley (SD) (10 weeks of age) rats were subjected to the 2VO, and DM was injected intraperitoneally once per day for 37 days. Neuron death, glial activation, and cognitive function were assessed at 37 days after 2VO (0.2 mg/kg, i.p., "DM-0.2" and 2 mg/kg, i.p., "DM-2"). DM-2 treatment provided protection against neuronal death and glial activation in the hippocampal CA1 subfield and reduced cognitive impairment induced by 2VO in rats. The study also demonstrates that activation of the Nrf2-HO-1 pathway and upregulation of superoxide dismutase (SOD) play important roles in these effects. These results suggest that DM is effective in treating VaD and protecting against oxidative stress, which is strongly implicated in the pathogenesis of VaD. Therefore, the present study suggests that DM treatment may represent a new and promising protective strategy for treating VaD. PMID:26887382

  12. IL-33 and IL-4 impair barrier functions of human vascular endothelium via different mechanisms.

    PubMed

    Chalubinski, Maciej; Wojdan, Katarzyna; Luczak, Emilia; Gorzelak, Paulina; Borowiec, Maciej; Gajewski, Adrian; Rudnicka, Karolina; Chmiela, Magdalena; Broncel, Marlena

    2015-10-01

    The vascular endothelium forms a barrier that controls flow of solutes and proteins and the entry of leukocytes into tissue. Injured tissue releases IL-33, which then alarms the immune system and attracts Th2 cells, thus increasing local concentration of IL-4. The aim of the study was to assess the influence of IL-33 and IL-4 on barrier functions of the human endothelium, expression of tight and adherent junction proteins, apoptosis and adhesive molecule surface expression in human endothelium in order to describe the mechanism of this effect. IL-33 and IL-4 decreased endothelial integrity and increased permeability. When added together, both cytokines lowered the endothelial integrity twice as much as used alone. This effect was accompanied by the down-regulation of occludin and VE-cadherin mRNA expression. Additionally, IL-4, but not IL-33, induced cell apoptosis. Both IL-33 and IL-4 showed the additive potency to down-regulate VE-cadherin mRNA expression. IL-33, unlike IL-4, increased the surface expression of ICAM-1, but not PECAM-1 in endothelial cells. Our results indicate that IL-33 may reversibly destabilize the endothelial barrier, thus accelerating the supply with immunomodulators and assisting leukocytes to reach wounded tissue. However, extended and less-controlled down-regulation of endothelial barrier, which may be a consequence of IL-33-initiated, but in fact IL-4-induced apoptosis of endothelial cells, may be deleterious and may eventually lead to the aggravation of inflammatory processes and the prolongation of tissue dysfunction. PMID:26231284

  13. TLR4-Activated MAPK-IL-6 Axis Regulates Vascular Smooth Muscle Cell Function.

    PubMed

    Lee, Guan-Lin; Wu, Jing-Yiing; Tsai, Chien-Sung; Lin, Chih-Yuan; Tsai, Yi-Ting; Lin, Chin-Sheng; Wang, Yi-Fu; Yet, Shaw-Fang; Hsu, Yu-Juei; Kuo, Cheng-Chin

    2016-01-01

    Migration of vascular smooth muscle cells (VSMCs) into the intima is considered to be a vital event in the pathophysiology of atherosclerosis. Despite substantial evidence supporting the pathogenic role of Toll-like receptor 4 (TLR4) in the progression of atherogenesis, its function in the regulation of VSMC migration remains unclear. The goal of the present study was to elucidate the mechanism by which TLR4 regulates VSMC migration. Inhibitor experiments revealed that TLR4-induced IL-6 secretion and VSMC migration were mediated via the concerted actions of MyD88 and TRIF on the activation of p38 MAPK and ERK1/2 signaling. Neutralizing anti-IL-6 antibodies abrogated TLR4-driven VSMC migration and F-actin polymerization. Blockade of p38 MAPK or ERK1/2 signaling cascade inhibited TLR4 agonist-mediated activation of cAMP response element binding protein (CREB). Moreover, siRNA-mediated suppression of CREB production repressed TLR4-induced IL-6 production and VSMC migration. Rac-1 inhibitor suppressed TLR4-driven VSMC migration but not IL-6 production. Importantly, the serum level of IL-6 and TLR4 endogenous ligand HMGB1 was significantly higher in patients with coronary artery diseases (CAD) than in healthy subjects. Serum HMGB1 level was positively correlated with serum IL-6 level in CAD patients. The expression of both HMGB1 and IL-6 was clearly detected in the atherosclerotic tissue of the CAD patients. Additionally, there was a positive association between p-CREB and HMGB1 in mouse atherosclerotic tissue. Based on our findings, we concluded that, upon ligand binding, TLR4 activates p38 MAPK and ERK1/2 signaling through MyD88 and TRIF in VSMCs. These signaling pathways subsequently coordinate an additive augmentation of CREB-driven IL-6 production, which in turn triggers Rac-1-mediated actin cytoskeleton to promote VSMC migration. PMID:27563891

  14. Changes in vascular plant functional types drive carbon cycling in peatlands

    NASA Astrophysics Data System (ADS)

    Zeh, Lilli; Bragazza, Luca; Erhagen, Björn; Limpens, Juul; Kalbitz, Karsten

    2016-04-01

    Northern peatlands store a large organic carbon (C) pool that is highly exposed to future environmental changes with consequent risk of releasing enormous amounts of C. Biotic changes in plant community structure and species abundance might have an even stronger impact on soil organic C dynamics in peatlands than the direct effects of abiotic changes. Therefore, a sound understanding of the impact of vegetation dynamics on C cycling will help to better predict the response of peatlands to environmental changes. Here, we aimed to assess the role of plant functional types (PFTs) in affecting peat decomposition in relation to climate warming. To this aim, we selected two peatlands at different altitude (i.e. 1300 and 1700 m asl) on the south-eastern Alps of Italy. The two sites represent a contrast in temperature, overall vascular plant biomass and relative ericoids abundance, with the highest biomass and ericoids occurrence at the low latitude. Within the sites we selected 20 plots of similar microtopographical position and general vegetation type (hummocks). All plots contained both graminoids and ericoids and had a 100% cover of Sphagnum mosses. The plots were subjected to four treatments (control, and three clipping treatments) in which we selectively removed aboveground biomass of ericoids, graminoids or both to explore the contribution of the different PFTs for soil respiration (n=5) and peat chemistry. Peat chemical composition was determined by the analysis of C and N and their stable isotopes in association with pyrolysis GC/MS. Soil respiration was measured after clipping with a Licor system. Preliminary findings suggest that peat decomposition pathway and rate depend on plant species composition and particularly on differences in root activity between PFTs. Finally, this study underlines the importance of biotic drivers to predict the effects of future environmental changes on peatland C cycling.

  15. Tertiary structure and function of an RNA motif required for plant vascular entry to initiate systemic trafficking.

    PubMed

    Zhong, Xuehua; Tao, Xiaorong; Stombaugh, Jesse; Leontis, Neocles; Ding, Biao

    2007-08-22

    Vascular entry is a decisive step for the initiation of long-distance movement of infectious and endogenous RNAs, silencing signals and developmental/defense signals in plants. However, the mechanisms remain poorly understood. We used Potato spindle tuber viroid (PSTVd) as a model to investigate the direct role of the RNA itself in vascular entry. We report here the identification of an RNA motif that is required for PSTVd to traffic from nonvascular into the vascular tissue phloem to initiate systemic infection. This motif consists of nucleotides U/C that form a water-inserted cis Watson-Crick/Watson-Crick base pair flanked by short helices that comprise canonical Watson-Crick/Watson-Crick base pairs. This tertiary structural model was inferred by comparison with X-ray crystal structures of similar motifs in rRNAs and is supported by combined mutagenesis and covariation analyses. Hydration pattern analysis suggests that water insertion induces a widened minor groove conducive to protein and/or RNA interactions. Our model and approaches have broad implications to investigate the RNA structural motifs in other RNAs for vascular entry and to study the basic principles of RNA structure-function relationships. PMID:17660743

  16. In vitro modeling of endothelial interaction with macrophages and pericytes demonstrates Notch signaling function in the vascular microenvironment.

    PubMed

    Tattersall, Ian W; Du, Jing; Cong, Zhuangzhuang; Cho, Bennet S; Klein, Alyssa M; Dieck, Chelsea L; Chaudhri, Reyhaan A; Cuervo, Henar; Herts, James H; Kitajewski, Jan

    2016-04-01

    Angiogenesis is regulated by complex interactions between endothelial cells and support cells of the vascular microenvironment, such as tissue myeloid cells and vascular mural cells. Multicellular interactions during angiogenesis are difficult to study in animals and challenging in a reductive setting. We incorporated stromal cells into an established bead-based capillary sprouting assay to develop assays that faithfully reproduce major steps of vessel sprouting and maturation. We observed that macrophages enhance angiogenesis, increasing the number and length of endothelial sprouts, a property we have dubbed "angiotrophism." We found that polarizing macrophages toward a pro-inflammatory profile further increased their angiotrophic stimulation of vessel sprouting, and this increase was dependent on macrophage Notch signaling. To study endothelial/pericyte interactions, we added vascular pericytes directly to the bead-bound endothelial monolayer. These pericytes formed close associations with the endothelial sprouts, causing increased sprout number and vessel caliber. We found that Jagged1 expression and Notch signaling are essential for the growth of both endothelial cells and pericytes and may function in their interaction. We observed that combining endothelial cells with both macrophages and pericytes in the same sprouting assay has multiplicative effects on sprouting. These results significantly improve bead-capillary sprouting assays and provide an enhanced method for modeling interactions between the endothelium and the vascular microenvironment. Achieving this in a reductive in vitro setting represents a significant step toward a better understanding of the cellular elements that contribute to the formation of mature vasculature. PMID:26965898

  17. Role of Vascular Networks in Extending Glucose Sensor Function: Impact of Angiogenesis and Lymphangiogenesis on Continuous Glucose Monitoring in vivo

    PubMed Central

    Klueh, Ulrike; Antar, Omar; Qiao, Yi; Kreutzer, Donald L.

    2014-01-01

    The concept of increased blood vessel (BV) density proximal to glucose sensors implanted in the interstitial tissue increases the accuracy and lifespan of sensors is accepted, despite limited existing experimental data. Interestingly, there is no previous data or even conjecture in the literature on the role of lymphatic vessels (LV) alone, or in combination with BV, in enhancing continuous glucose monitoring (CGM) in vivo. To investigate the impact of inducing vascular networks (BV and LV) at sites of glucose sensor implantation, we utilized adenovirus based local gene therapy of vascular endothelial cell growth factor-A (VEGF-A) to induce vessels at sensor implantation sites. The results of these studies demonstrated that 1) VEGF-A based local gene therapy increases vascular networks (blood vessels and lymphatic vessels) at sites of glucose sensor implantation; and 2) this local increase of vascular networks enhances glucose sensor function in vivo from 7 days to greater than 28 days post sensor implantation. This data provides “proof of concept” for the effective usage of local angiogenic factor (AF) gene therapy in mammalian models in an effort to extend CGM in vivo. It also supports the practice of a variety of viral and non-viral vectors as well as gene products (e.g. anti-inflammatory and anti-fibrosis genes) to engineer “implant friendly tissues” for the usage with implantable glucose sensors as well as other implantable devices. PMID:24243850

  18. Regulation of Microvascular Function by Adipose Tissue in Obesity and Type 2 Diabetes: Evidence of an Adipose-Vascular Loop

    PubMed Central

    Zhang, Hanrui; Zhang, Cuihua

    2009-01-01

    In recent years, the general concept has emerged that chronic low-grade inflammation is the condition linking excessive development of adipose tissue and obesity-associated pathologies such as type 2 diabetes and cardiovascular diseases. Obesity and type 2 diabetes are characterized by a diminished production of protective factors such as adiponectin and increased detrimental adipocytokines such as leptin, resistin, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNFα), and monocyte chemoattractant protein-1 (MCP-1) by adipose tissue. Moreover, the evidence that the growth of the fat mass is associated with an accumulation of adipose tissue macrophages and T-lymphocytes has raised the hypothesis that the development of an inflammatory process within the growing fat mass is a primary event involved in the genesis of systemic metabolic and vascular alterations. This crosstalk of adipocyte, macrophage, lymphocyte, endothelial cells, and vascular smooth muscle cells contribute to the production of various cytokines, chemokines, and hormone-like factors, which actively participate in the regulation of vascular function by an endocrine and/or paracrine pattern. Thus, the signaling from perivascular adipose to the blood vessels is emerging as a potential therapeutic target for obesity and diabetes-associated vascular dysfunction. PMID:20098632

  19. Effects of bosentan on peripheral endothelial function in patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension

    PubMed Central

    Adachi, Shiro; Nakano, Yoshihisa; Kamimura, Yoshihiro; Shimokata, Shigetake; Takeshita, Kyosuke; Murohara, Toyoaki; Kondo, Takahisa

    2016-01-01

    Abstract Endothelin receptor antagonists (ERAs) have been shown to improve the prognosis of patients with pulmonary arterial hypertension (PAH). However, the effect of the oral dual ERA bosentan on peripheral endothelial dysfunction (PED), as assessed by flow-mediated vasodilation (FMD), in patients with pulmonary hypertension is not well characterized. We investigated the effect of bosentan on PED in patients with PAH or inoperable chronic thromboembolic pulmonary hypertension (CTEPH). A total of 18 patients with PAH and 8 with CTEPH were treated with bosentan. All patients underwent FMD assessment before and after 3 months of bosentan treatment. Whereas FMD increased from 6.01% ± 2.42% at baseline to 8.07% ± 3.18% after 3 months (P < 0.0001) in patients with PAH, those with CTEPH showed no change in FMD after bosentan therapy. In addition, FMD at baseline showed no correlation with pulmonary vascular resistance (r = 0.09) or plasma brain natriuretic peptide levels (r = −0.23) in patients with PAH. Bosentan treatment ameliorated PED in patients with PAH but not in those with inoperable CTEPH. In addition, FMD did not correlate with PAH severity. PMID:27252842

  20. Treatment of peripheral arterial disease in diabetes: a consensus of the Italian Societies of Diabetes (SID, AMD), Radiology (SIRM) and Vascular Endovascular Surgery (SICVE).

    PubMed

    Aiello, A; Anichini, R; Brocco, E; Caravaggi, C; Chiavetta, A; Cioni, R; Da Ros, R; De Feo, M E; Ferraresi, R; Florio, F; Gargiulo, M; Galzerano, G; Gandini, R; Giurato, L; Graziani, L; Mancini, L; Manzi, M; Modugno, P; Setacci, C; Uccioli, L

    2014-04-01

    Diabetic foot (DF) is a chronic and highly disabling complication of diabetes. The prevalence of peripheral arterial disease (PAD) is high in diabetic patients and, associated or not with peripheral neuropathy (PN), can be found in 50% of cases of DF. It is worth pointing out that the number of major amputations in diabetic patients is still very high. Many PAD diabetic patients are not revascularised due to lack of technical expertise or, even worse, negative beliefs because of poor experience. This despite the progress obtained in the techniques of distal revascularisation that nowadays allow to reopen distal arteries of the leg and foot. Italy has one of the lowest prevalence rates of major amputations in Europe, and has a long tradition in the field of limb salvage by means of an aggressive approach in debridement, antibiotic therapy and distal revascularisation. Therefore, we believe it is appropriate to produce a consensus document concerning the treatment of PAD and limb salvage in diabetic patients, based on the Italian experience in this field, to share with the scientific community. PMID:24486336

  1. You're Only as Old as Your Arteries: Translational Strategies for Preserving Vascular Endothelial Function with Aging

    PubMed Central

    Kaplon, Rachelle E.; Gioscia-Ryan, Rachel A.; LaRocca, Thomas J.

    2014-01-01

    Endothelial dysfunction develops with age and increases the risk of age-associated vascular disorders. Nitric oxide insufficiency, oxidative stress, and chronic low-grade inflammation, induced by upregulation of adverse cellular signaling processes and imbalances in stress resistance pathways, mediate endothelial dysfunction with aging. Healthy lifestyle behaviors preserve endothelial function with aging by inhibiting these mechanisms, and novel nutraceutical compounds that favorably modulate these pathways hold promise as a complementary approach for preserving endothelial health. PMID:24985329

  2. Vascular function and nitric oxide production in chronic social-stress-exposed rats with various family history of hypertension.

    PubMed

    Bernatowa, I; Csizmadiova, Z; Kopincova, J; Puzserova, A

    2007-09-01

    The study investigated the effect of chronic crowding stress on vascular function and nitric oxide (NO) production in rats with various family history of hypertension. Wistar (W), wBHR (offspring of W dams and spontaneously hypertensive sires), sBHR (offspring of spontaneously hypertensive dams and W sires) and spontaneously hypertensive rats (SHR) were used. Twelve-week-old males were divided into the control or crowded group for eight weeks. Basal blood pressure (BP, determined by tail-cuff plethysmography) of W, wBHR, sBHR and SHR rats was 112 +/- 3, 129 +/- 2, 135 +/- 2 and 187 +/- 3 mmHg, respectively. Crowding increased BP and reduced aortic NO synthase activity only in sBHR and SHR rats, without alterations in hypothalamic NO production. Acetylcholine-induced vasorelaxation of the femoral artery of stress-exposed rats was improved in W, unaltered in wBHR and sBHR and reduced in SHR. Crowding reduced serotonin-induced vasoconstriction in W and wBHR rats but had no effect in sBHR and SHR rats. In conclusion, the results suggest that crowded offspring of normotensive mothers were able to modify their vascular function in order to maintain BP at normal levels. On the other hand, offspring of hypertensive mothers were unable of effective adaptation of vascular function in stressful conditions resulting in gradual development of hypertension. PMID:17928645

  3. Classical cardiovascular disease risk factors associate with vascular function and morphology in rheumatoid arthritis: a six-year prospective study

    PubMed Central

    2013-01-01

    Introduction Patients with rheumatoid arthritis (RA) are at an increased risk for cardiovascular disease (CVD). An early manifestation of CVD is endothelial dysfunction which can lead to functional and morphological vascular abnormalities. Classical CVD risk factors and inflammation are both implicated in causing endothelial dysfunction in RA. The objective of the present study was to examine the effect of baseline inflammation, cumulative inflammation, and classical CVD risk factors on the vasculature following a six-year follow-up period. Methods A total of 201 RA patients (155 females, median age (25th to 75th percentile): 61 years (53 to 67)) were examined at baseline (2006) for presence of classical CVD risk factors and determination of inflammation using C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). At follow-up (2012) patients underwent assessments of microvascular and macrovascular endothelium-dependent and endothelium-independent function, along with assessment of carotid atherosclerosis. The CRP and ESR were recorded from the baseline study visit to the follow-up visit for each patient to calculate cumulative inflammatory burden. Results Classical CVD risk factors, but not RA disease-related inflammation, predicted microvascular endothelium-dependent and endothelium-independent function, macrovascular endothelium-independent function and carotid atherosclerosis. These findings were similar in a sub-group of patients free from CVD, and not receiving non-steroidal anti-inflammatory drugs, cyclooxygenase 2 inhibitors or biologics. Cumulative inflammation was not associated with microvascular and macrovascular endothelial function, but a weak association was apparent between area under the curve for CRP and carotid atherosclerosis. Conclusions Classical CVD risk factors may be better long-term predictors of vascular function and morphology than systemic disease-related inflammation in patients with RA. Further studies are needed to

  4. Postprandial hyperglycemia impairs vascular endothelial function in healthy men by inducing lipid peroxidation and increasing asymmetric dimethylarginine:arginine.

    PubMed

    Mah, Eunice; Noh, Sang K; Ballard, Kevin D; Matos, Manuel E; Volek, Jeff S; Bruno, Richard S

    2011-11-01

    Postprandial hyperglycemia induces vascular endothelial dysfunction (VED) and increases future cardiovascular disease risk. We hypothesized that postprandial hyperglycemia would decrease vascular function in healthy men by inducing oxidative stress and proinflammatory responses and increasing asymmetric dimethylarginine:arginine (ADMA:arginine), a biomarker that is predictive of reduced NO biosynthesis. In a randomized, cross-over design, healthy men (n = 16; 21.6 ± 0.8 y) ingested glucose or fructose (75 g) after an overnight fast. Brachial artery flow-mediated dilation (FMD), plasma glucose and insulin, antioxidants, malondialdehyde (MDA), inflammatory proteins, arginine, and ADMA were measured at regular intervals during the 3-h postprandial period. Baseline FMD did not differ between trials (P > 0.05). Postprandial FMD was reduced following the ingestion of glucose only. Postprandial MDA concentrations increased to a greater extent following the ingestion of glucose compared to fructose. Plasma arginine decreased and the ratio of ADMA:arginine increased to a greater extent following the ingestion of glucose. Inflammatory cytokines and cellular adhesion molecules were unaffected by the ingestion of either sugar. Postprandial AUC(0-3 h) for FMD and MDA were inversely related (r = -0.80; P < 0.05), suggesting that hyperglycemia-induced lipid peroxidation suppresses postprandial vascular function. Collectively, these findings suggest that postprandial hyperglycemia in healthy men reduces endothelium-dependent vasodilation by increasing lipid peroxidation independent of inflammation. Postprandial alterations in arginine and ADMA:arginine also suggest that acute hyperglycemia may induce VED by decreasing NO bioavailability through an oxidative stress-dependent mechanism. Additional work is warranted to define whether inhibiting lipid peroxidation and restoring arginine metabolism would mitigate hyperglycemia-mediated decreases in vascular function. PMID:21940510

  5. Vascular permeability, vascular hyperpermeability and angiogenesis

    PubMed Central

    Nagy, Janice A.; Benjamin, Laura; Zeng, Huiyan; Dvorak, Ann M.

    2008-01-01

    The vascular system has the critical function of supplying tissues with nutrients and clearing waste products. To accomplish these goals, the vasculature must be sufficiently permeable to allow the free, bidirectional passage of small molecules and gases and, to a lesser extent, of plasma proteins. Physiologists and many vascular biologists differ as to the definition of vascular permeability and the proper methodology for its measurement. We review these conflicting views, finding that both provide useful but complementary information. Vascular permeability by any measure is dramatically increased in acute and chronic inflammation, cancer, and wound healing. This hyperpermeability is mediated by acute or chronic exposure to vascular permeabilizing agents, particularly vascular permeability factor/vascular endothelial growth factor (VPF/VEGF, VEGF-A). We demonstrate that three distinctly different types of vascular permeability can be distinguished, based on the different types of microvessels involved, the composition of the extravasate, and the anatomic pathways by which molecules of different size cross-vascular endothelium. These are the basal vascular permeability (BVP) of normal tissues, the acute vascular hyperpermeability (AVH) that occurs in response to a single, brief exposure to VEGF-A or other vascular permeabilizing agents, and the chronic vascular hyperpermeability (CVH) that characterizes pathological angiogenesis. Finally, we list the numerous (at least 25) gene products that different authors have found to affect vascular permeability in variously engineered mice and classify them with respect to their participation, as far as possible, in BVP, AVH and CVH. Further work will be required to elucidate the signaling pathways by which each of these molecules, and others likely to be discovered, mediate the different types of vascular permeability. PMID:18293091

  6. Circulating immune complexes of calves with bronchopneumonia modulate the function of peripheral blood leukocytes: In vitro evaluation.

    PubMed

    Buač, Marijana; Mojsilović, Slavko; Mišić, Dušan; Vuković, Dejan; Savić, Olivera; Valčić, Olivera; Marković, Dragana; Gvozdić, Dragan; Ilić, Vesna; Fratrić, Natalija

    2016-06-01

    In this work we studied if circulating immune complexes (CIC) of calves with bronchopneumonia have the capacity to modulate function of peripheral blood leukocytes of healthy cattle. CIC of three month old calves (6 healthy and 6 diseased) were isolated by PEG precipitation. Peripheral blood mononuclear cells (MNCs) and granulocytes from healthy calves and cows were the CIC responder cells in in vitro tests. The most remarkable increase of adhesiveness to polystyrene and ROS synthesis (assessed by NBT test) was detected in cows' granulocytes stimulated with CIC of diseased calves. Results of MTT test showed that CIC of both healthy and diseased calves reduced granulocytes' viability. The strongest effect of inhibition of cows' granulocytes resulted from CIC of diseased calves. CIC only moderately reduced spontaneous viability of calves' MNCs. Again, the strongest effect of CIC isolated from diseased calves was observed. In contrast to the low impact of CIC on non-stimulated cells, their inhibitory effect on viability of mitogen stimulated MNCs was very strong. With CFSE assay we showed that both types of CIC stimulated spontaneous, but inhibited mitogen induced proliferation of calves' MNCs. Propidium iodide staining reviled that CIC increased apoptosis/necrosis of both non-stimulated and mitogen stimulated MNCs. CIC of both healthy and diseased calves modulated the function of peripheral blood MNCs and granulocytes, but a stronger effect of CIC of diseased calves was shown. The age of the donors (calves or cows) of the responder cells, and the activation state of these cells, were also of influence. PMID:27234551

  7. Aldosterone-Induced Vascular Remodeling and Endothelial Dysfunction Require Functional Angiotensin Type 1a Receptors.

    PubMed

    Briet, Marie; Barhoumi, Tlili; Mian, Muhammad Oneeb Rehman; Coelho, Suellen C; Ouerd, Sofiane; Rautureau, Yohann; Coffman, Thomas M; Paradis, Pierre; Schiffrin, Ernesto L

    2016-05-01

    We investigated the role of angiotensin type 1a receptors (AGTR1a) in vascular injury induced by aldosterone activation of mineralocorticoid receptors in Agtr1a(-/-) and wild-type (WT) mice infused with aldosterone for 14 days while receiving 1% NaCl in drinking water. Aldosterone increased systolic blood pressure (BP) by ≈30 mm Hg in WT mice and ≈50 mm Hg in Agtr1a(-/-) mice. Aldosterone induced aortic and small artery remodeling, impaired endothelium-dependent relaxation in WT mice, and enhanced fibronectin and collagen deposition and vascular inflammation. None of these vascular effects were observed in Agtr1a(-/-) mice. Aldosterone effects were prevented by the AGTR1 antagonist losartan in WT mice. In contrast to aldosterone, norepinephrine caused similar BP increase and mesenteric artery remodeling in WT and Agtr1a(-/-) mice. Agtr1a(-/-) mice infused with aldosterone did not increase sodium excretion in response to a sodium chloride challenge, suggesting that sodium retention could contribute to the exaggerated BP rise induced by aldosterone. Agtr1a(-/-) mice had decreased mesenteric artery expression of the calcium-activated potassium channel Kcnmb1, which may enhance myogenic tone and together with sodium retention, exacerbate BP responses to aldosterone/salt in Agtr1a(-/-) mice. We conclude that although aldosterone activation of mineralocorticoid receptors raises BP more in Agtr1a(-/-) mice, AGTR1a is required for mineralocorticoid receptor stimulation to induce vascular remodeling and inflammation and endothelial dysfunction. PMID:27045029

  8. In vitro effects of waterpipe smoke condensate on endothelial cell function: A potential risk factor for vascular disease

    PubMed Central

    Rammah, Mayyasa; Dandachi, Farah; Salman, Rola; Shihadeh, Alan; El-Sabban, Marwan

    2013-01-01

    Aim Despite its increasing popularity, little is known about the health effects of waterpipe smoking (WPS), particularly on the cardiovascular system. To investigate the role of WPS as a risk factor for vascular disease, we evaluated its effect on endothelial cell function, which is an early event in vascular disease pathogenesis. We assessed the changes in cell viability, ROS generation, inflammatory and vasodilatory markers and in vitro angiogenesis of human aortic endothelial cells in response to waterpipe smoke condensate exposure. Methods and results Mainstream waterpipe smoke condensate (WSC) was generated using a standard laboratory machine protocol. Compared to control, WSC induced cell cycle arrest, apoptosis, and oxidative stress in human primary endothelial cells. In addition, we assayed for impaired endothelium-dependent vasodilation and induced inflammation by studying the effect of WPS on the content and activity of AMPK, eNOS proteins and NF-κB p65 ser536 phosphorylation, respectively. WSC inhibited AMPK/eNOS phosphorylation and induced phosphorylation of p65. Moreover, we evaluated endothelial cells repair mechanism related properties that include migration/invasion and in vitro tube formation upon treatment with WSC. WSC reduced the motility and inhibited angiogenic potential of HAEC cells. Conclusions WPS induced endothelial cell dysfunction as evident by exerting oxidative stress, inflammation, and impaired endothelial vasodilatory function and repair mechanisms. All together these data provide evidence for the potential contribution of WPS to endothelial dysfunction and thus to vascular disease. PMID:23454654

  9. Effect of soy isoflavone supplementation on vascular endothelial function and oxidative stress in postmenopausal women: a community randomized controlled trial.

    PubMed

    Pusparini; Dharma, Rahayuningsih; Suyatna, Fransiscus D; Mansyur, Muchtaruddin; Hidajat, Adi

    2013-01-01

    A 12-month randomized double blind controlled trial was conducted among 182 Indonesian postmenopausal women aged 47 to 60 years to determine the effect of 100 mg/day soy isoflavone supplementation on vascular endothelial function such as vascular cell adhesion molecule-1 (VCAM-1), nitric oxide (NO) and malondialdehyde (MDA) as oxidative stress marker. The subjects were randomized to the intervention group receiving tablets consisting of 100 mg soy isoflavones and calcium carbonate 500 mg, and to the control group receiving 500 mg calcium carbonate. The concentrations of VCAM-1, NO and MDA were measured at baseline, and postsupplementation at 6 months and 12 months. After supplementation, the MDA concentrations were significantly lower in the soy isoflavone group compared with the control group (p=0.001). The concentrations of VCAM-1 and NO were not affected (p=0.992 and p=0.759, respectively). In all group the MDA concentration increased compared with baseline concentrations but the relative change of MDA concentrations was significantly lower in the soy isoflavone group compared with the control group. This study demonstrates that supplemental intake of soy isoflavones for 6 months and 12 months had an effect on oxidative stress by decreasing MDA concentration, but did not improve vascular endothelial function. PMID:23945405

  10. Catechin averts experimental diabetes mellitus-induced vascular endothelial structural and functional abnormalities.

    PubMed

    Bhardwaj, Pooja; Khanna, Deepa; Balakumar, Pitchai

    2014-03-01

    Diabetes mellitus is associated with an induction of vascular endothelial dysfunction (VED), an initial event that could lead to the pathogenesis of atherosclerosis and hypertension. Previous studies showed that catechin, a key component of green tea, possesses vascular beneficial effects. We investigated the effect of catechin hydrate in diabetes mellitus-induced experimental vascular endothelial abnormalities (VEA). Streptozotocin (50 mg/kg, i.p., once) administration to rats produced diabetes mellitus, which subsequently induced VEA in 8 weeks by markedly attenuating acetylcholine-induced endothelium-dependent relaxation in the isolated aortic ring preparation, decreasing aortic and serum nitrite/nitrate concentrations and impairing aortic endothelial integrity. These abnormalities in diabetic rats were accompanied with elevated aortic superoxide anion generation and serum lipid peroxidation in addition to hyperglycemia. Catechin hydrate treatment (50 mg/kg/day p.o., 3 weeks) markedly prevented diabetes mellitus-induced VEA and vascular oxidative stress. Intriguingly, in vitro incubation of L-NAME (100 μM), an inhibitor of nitric oxide synthase, or Wortmannin (100 nM), a selective inhibitor of phosphatidylinositol 3-kinase (PI3K), markedly prevented catechin hydrate-induced improvement in acetylcholine-provoked endothelium-dependent relaxation in the diabetic rat aorta. Moreover, catechin hydrate treatment considerably reduced the elevated level of serum glucose in diabetic rats. In conclusion, catechin hydrate treatment prevents diabetes mellitus-induced VED through the activation of endothelial PI3K signal and subsequent activation of eNOS and generation of nitric oxide. In addition, reduction in high glucose, vascular oxidative stress, and lipid peroxidation might additionally contribute to catechin hydrate-associated prevention of diabetic VEA. PMID:24048981

  11. Localized and Sustained Delivery of Erythropoietin from PLGA Microspheres Promotes Functional Recovery and Nerve Regeneration in Peripheral Nerve Injury

    PubMed Central

    Zhang, Wei; Gao, Yuan; Zhou, Yan; Liu, Jianheng; Zhang, Licheng; Long, Anhua; Zhang, Lihai; Tang, Peifu

    2015-01-01

    Erythropoietin (EPO) has been demonstrated to exert neuroprotective effects on peripheral nerve injury recovery. Though daily intraperitoneal injection of EPO during a long period of time was effective, it was a tedious procedure. In addition, only limited amount of EPO could reach the injury sites by general administra