Ultra-Widefield Fluorescein Angiography in Intermediate Uveitis.

PubMed

Laovirojjanakul, Wipada; Acharya, Nisha; Gonzales, John A

2017-10-17

To examine associations between pattern of vascular leakage on ultrawide-field fluorescein angiography (UWFFA) and visual acuity, cystoid macular edema (CME), and inflammatory activity in intermediate uveitis. Single center cross-sectional, retrospective review of medical records, spectral domain optical coherence tomography (SD-OCT) and angiographic images of intermediate uveitis patients who underwent UWFFA over a 12-month period. Forty-one eyes from 24 patients were included. Twelve eyes (29%) exhibited peripheral leakage, 26 eyes (64%) had diffuse leakage and three eyes (7%) had no leakage. Diffuse leakage was associated with 0.2 logMAR worse visual acuity than peripheral leakage (p = 0.02). There was no statistically significant difference in the odds of having CME when diffuse leakage was compared to peripheral leakage. UWFFA identifies retinal vascular pathology in intermediate uveitis not present on clinical examination. Diffuse retinal vascular leakage was associated with worse visual acuity when compared to peripheral and no leakage patterns.

Mitochondrial Respiration after One Session of Calf Raise Exercise in Patients with Peripheral Vascular Disease and Healthy Older Adults

PubMed Central

Wohlwend, Martin; Rognmo, Øivind; Mattsson, Erney J. R.

2016-01-01

Purpose Mitochondria are essential for energy production in the muscle cell and for this they are dependent upon a sufficient supply of oxygen by the circulation. Exercise training has shown to be a potent stimulus for physiological adaptations and mitochondria play a central role. Whether changes in mitochondrial respiration are seen after exercise in patients with a reduced circulation is unknown. The aim of the study was to evaluate the time course and whether one session of calf raise exercise stimulates mitochondrial respiration in the calf muscle of patients with peripheral vascular disease. Methods One group of patients with peripheral vascular disease (n = 11) and one group of healthy older adults (n = 11) were included. Patients performed one session of continuous calf raises followed by 5 extra repetitions after initiation of pain. Healthy older adults performed 100 continuous calf raises. Gastrocnemius muscle biopsies were collected at baseline and 15 minutes, one hour, three hours and 24 hours after one session of calf raise exercise. A multi substrate (octanoylcarnitine, malate, adp, glutamate, succinate, FCCP, rotenone) approach was used to analyze mitochondrial respiration in permeabilized fibers. Mixed-linear model for repeated measures was used for statistical analyses. Results Patients with peripheral vascular disease have a lower baseline respiration supported by complex I and they increase respiration supported by complex II at one hour post-exercise. Healthy older adults increase respiration supported by electron transfer flavoprotein and complex I at one hour and 24 hours post-exercise. Conclusion Our results indicate a shift towards mitochondrial respiration supported by complex II as being a pathophysiological component of peripheral vascular disease. Furthermore exercise stimulates mitochondrial respiration already after one session of calf raise exercise in patients with peripheral vascular disease and healthy older adults. Trial Registration ClinicalTrials.gov NCT01842412 PMID:27760222

Angiogenic T cell expansion correlates with severity of peripheral vascular damage in systemic sclerosis.

PubMed

Manetti, Mirko; Pratesi, Sara; Romano, Eloisa; Bellando-Randone, Silvia; Rosa, Irene; Guiducci, Serena; Fioretto, Bianca Saveria; Ibba-Manneschi, Lidia; Maggi, Enrico; Matucci-Cerinic, Marco

2017-01-01

The mechanisms underlying endothelial cell injury and defective vascular repair in systemic sclerosis (SSc) remain unclear. Since the recently discovered angiogenic T cells (Tang) may have an important role in the repair of damaged endothelium, this study aimed to analyze the Tang population in relation to disease-related peripheral vascular features in SSc patients. Tang (CD3+CD31+CXCR4+) were quantified by flow cytometry in peripheral blood samples from 39 SSc patients and 18 healthy controls (HC). Circulating levels of the CXCR4 ligand stromal cell-derived factor (SDF)-1α and proangiogenic factors were assessed in paired serum samples by immunoassay. Serial skin sections from SSc patients and HC were subjected to CD3/CD31 and CD3/CXCR4 double immunofluorescence. Circulating Tang were significantly increased in SSc patients with digital ulcers (DU) compared either with SSc patients without DU or with HC. Tang levels were significantly higher in SSc patients with late nailfold videocapillaroscopy (NVC) pattern than in those with early/active NVC patterns and in HC. No difference in circulating Tang was found when comparing either SSc patients without DU or patients with early/active NVC patterns and HC. In SSc peripheral blood, Tang percentage was inversely correlated to levels of SDF-1α and CD34+CD133+VEGFR-2+ endothelial progenitor cells (EPC), and positively correlated to levels of vascular endothelial growth factor and matrix metalloproteinase-9. Tang were frequently detected in SSc dermal perivascular inflammatory infiltrates. In summary, our findings demonstrate for the first time that Tang cells are selectively expanded in the circulation of SSc patients displaying severe peripheral vascular complications like DU. In SSc, Tang may represent a potentially useful biomarker reflecting peripheral vascular damage severity. Tang expansion may be an ineffective attempt to compensate the need for increased angiogenesis and EPC function. Further studies are required to clarify the function of Tang cells and investigate the mechanisms responsible for their change in SSc.

False Positive Stress Testing: Does Endothelial Vascular Dysfunction Contribute to ST-Segment Depression in Women? A Pilot Study.

PubMed

Sharma, Shilpa; Mehta, Puja K; Arsanjani, Reza; Sedlak, Tara; Hobel, Zachary; Shufelt, Chrisandra; Jones, Erika; Kligfield, Paul; Mortara, David; Laks, Michael; Diniz, Marcio; Bairey Merz, C Noel

2018-06-19

The utility of exercise-induced ST-segment depression for diagnosing ischemic heart disease (IHD) in women is unclear. Based on evidence that IHD pathophysiology in women involves coronary vascular dysfunction, we hypothesized that coronary vascular dysfunction contributes to exercise electrocardiography (Ex-ECG) ST-depression in the absence of obstructive CAD, so-called "false positive" results. We tested our hypothesis in a pilot study evaluating the relationship between peripheral vascular endothelial function and Ex-ECG. Twenty-nine asymptomatic women without cardiac risk factors underwent maximal Bruce protocol exercise treadmill testing and peripheral endothelial function assessment using peripheral arterial tonometry (Itamar EndoPAT 2000) to measure reactive hyperemia index (RHI). The relationship between RHI and Ex-ECG ST-segment depression was evaluated using logistic regression and differences in subgroups using two-tailed t-tests. Mean age was 54 ± 7 years, body mass index 25 ± 4 kg/m 2 , and RHI 2.51 ± 0.66. Three women (10%) had RHI less than 1.68, consistent with abnormal peripheral endothelial function, while 18 women (62%) met criteria for a positive Ex-ECG based on ST-segment depression in contiguous leads. Women with and without ST-segment depression had similar baseline and exercise vital signs, metabolic equivalents (METS) achieved, and RHI (all p>0.05). RHI did not predict ST-segment depression. Our pilot study demonstrates a high prevalence of exercise-induced ST-segment depression in asymptomatic, middle-aged, overweight women. Peripheral vascular endothelial dysfunction did not predict Ex-ECG ST-segment depression. Further work is needed to investigate the utility of vascular endothelial testing and Ex-ECG for IHD diagnostic and management purposes in women. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

The development of self-expanding peripheral stent with ion-modified surface layer

NASA Astrophysics Data System (ADS)

Lotkov, Alexander I.; Kashin, Oleg A.; Kudryashov, Andrey N.; Krukovskii, Konstantin V.; Kuznetsov, Vladimir M.; Borisov, Dmitry P.; Kretov, Evgenii I.

2016-11-01

In work researches of chemical composition of surface layers of self-expanding stents of nickel-titanium (NiTi) and their functional and mechanical properties after plasma immersion processing by ions of silicon (Si). It is established that in the treatment in the inner and outer surfaces of stents formed doped silicon layer with a thickness of 80 nm. The formation of the doped layer does not impair the functional properties of the stent. At human body temperature, the stent is fully restore its shape after removing the deforming load. The resulting graph of loading of stents during their compression between parallel plates. The research results allow the conclusion that Si-doped stents are promising for treatment of peripheral vascular disease. However, related studies on laboratory animals are required.

Ultra-widefield fluorescein angiography of white without pressure

PubMed Central

Orlin, Anton; Fatoo, Aalya; Ehrlich, Joshua; D’Amico, Donald J; Chan, RV Paul; Kiss, Szilárd

2013-01-01

Purpose To describe ultra-widefield fluorescein angiography (UWFA) findings in eyes with white without pressure (WWOP) and in eyes without any obvious peripheral chorioretinal disease, and to determine if a difference exists between these two groups. Methods A retrospective review of 379 eyes undergoing diagnostic UWFA using the Optos 200Tx imaging system. Eyes were excluded if the quality of the color photograph or UWFA prevented reliable evaluation. Eyes were also excluded if there was any evidence of peripheral retinal or choroidal disease, which was thought to have an effect on UWFA (eg, peripheral background diabetic or hypertensive retinopathy, vein occlusion, or any other peripheral vascular disorder). Eyes were determined to have WWOP, based on a dilated fundus examination and color fundus photography that contained areas of peripheral retinal whitening consistent with the diagnosis. UWFA was evaluated by trained masked graders, and determined to have or not have peripheral vascular leakage and/or staining. Results Of the 379 eyes evaluated, 45 eyes were included in the study. Twelve eyes were determined to have peripheral WWOP; 33 eyes did not have WWOP on examination or color fundus photography. Three common UWFA peripheral patterns were visualized. Eyes with and without WWOP were grouped into one of three patterns. The majority of eyes without WWOP demonstrated UWFA pattern one (69.7%), while those in the WWOP group demonstrated pattern three (50%). The distribution of UWFA patterns is statistically different between those with and without WWOP (P = 0.002). In eyes without WWOP, in patients with no documented systemic microvascular disease (diabetes, hypertension), 71.4% of eyes had UWFA pattern one while 14.3% had both patterns two and three. Conclusion This study is one of the first to specifically evaluate peripheral vascular leakage/staining in eyes with WWOP as well as in eyes without any obvious peripheral chorioretinal disease. We demonstrate that a significant portion of WWOP eyes exhibit peripheral findings on UWFA (pattern one) compared to eyes without WWOP. Importantly, even in eyes that are apparently unremarkable in the periphery on exam and color photography, UWFA can still show peripheral vascular abnormalities. These results warrant further investigation. PMID:23737658

Regional peripheral and CNS hemodynamic effects of intrathecal administration of a substance P receptor agonist.

PubMed

Helke, C J; Phillips, E T; O'Neill, J T

1987-11-01

Regional CNS and peripheral hemodynamic effects of the intrathecal (i.t.) administration of a substance P receptor agonist, [pGlu5,MePhe8,MeGly9]-substance P5-11 ([DiMe]-SP), were studied in anesthetized rats with the radioactive microsphere technique. It was previously shown that [DiMe]-SP caused a sympathetically mediated increase in mean arterial pressure (MAP) by an action within the spinal cord. In this study, [DiMe]-SP (5 and 33 nmol, i.t.) increased MAP. The 5 nmol dose increased resistance in cutaneous, renal, splanchnic, and adrenal vascular beds but decreased resistance, and increased blood flow in some skeletal muscle beds. Total peripheral resistance was unchanged. The 33 nmol dose increased resistance in each peripheral vascular bed analyzed and increased total peripheral resistance. Whereas each dose increased heart rate, stroke volume and cardiac output were unchanged with the 5 nmol dose and were reduced with the 33 nmol dose. Neither dose of [DiMe]-SP significantly altered regional brain or spinal cord blood flows. These data show that the i.t. administration of the SP agonist, [DiMe]-SP, increased vascular tone to most peripheral vascular beds whereas the low dose caused a vasodilation of skeletal muscle. These effects are consistent with the notion of a dose-related activation of SP receptors in the spinal cord affecting sympathetic outflow to the adrenals and to the vasculature.

Whole-mount Confocal Microscopy for Adult Ear Skin: A Model System to Study Neuro-vascular Branching Morphogenesis and Immune Cell Distribution.

PubMed

Yamazaki, Tomoko; Li, Wenling; Mukouyama, Yoh-Suke

2018-03-29

Here, we present a protocol of a whole-mount adult ear skin imaging technique to study comprehensive three-dimensional neuro-vascular branching morphogenesis and patterning, as well as immune cell distribution at a cellular level. The analysis of peripheral nerve and blood vessel anatomical structures in adult tissues provides some insights into the understanding of functional neuro-vascular wiring and neuro-vascular degeneration in pathological conditions such as wound healing. As a highly informative model system, we have focused our studies on adult ear skin, which is readily accessible for dissection. Our simple and reproducible protocol provides an accurate depiction of the cellular components in the entire skin, such as peripheral nerves (sensory axons, sympathetic axons, and Schwann cells), blood vessels (endothelial cells and vascular smooth muscle cells), and inflammatory cells. We believe this protocol will pave the way to investigate morphological abnormalities in peripheral nerves and blood vessels as well as the inflammation in the adult ear skin under different pathological conditions.

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

Contact area affects frequency-dependent responses to vibration in the peripheral vascular and sensorineural systems.

PubMed

Krajnak, Kristine; Miller, G R; Waugh, Stacey

2018-01-01

Repetitive exposure to hand-transmitted vibration is associated with development of peripheral vascular and sensorineural dysfunctions. These disorders and symptoms associated with it are referred to as hand-arm vibration syndrome (HAVS). Although the symptoms of the disorder have been well characterized, the etiology and contribution of various exposure factors to development of the dysfunctions are not well understood. Previous studies performed using a rat-tail model of vibration demonstrated that vascular and peripheral nervous system adverse effects of vibration are frequency-dependent, with vibration frequencies at or near the resonant frequency producing the most severe injury. However, in these investigations, the amplitude of the exposed tissue was greater than amplitude typically noted in human fingers. To determine how contact with vibrating source and amplitude of the biodynamic response of the tissue affects the risk of injury occurring, this study compared the influence of frequency using different levels of restraint to assess how maintaining contact of the tail with vibrating source affects the transmission of vibration. Data demonstrated that for the most part, increasing the contact of the tail with the platform by restraining it with additional straps resulted in an enhancement in transmission of vibration signal and elevation in factors associated with vascular and peripheral nerve injury. In addition, there were also frequency-dependent effects, with exposure at 250 Hz generating greater effects than vibration at 62.5 Hz. These observations are consistent with studies in humans demonstrating that greater contact and exposure to frequencies near the resonant frequency pose the highest risk for generating peripheral vascular and sensorineural dysfunction.

Effect of Vegan Fecal Microbiota Transplantation on Carnitine- and Choline-Derived Trimethylamine-N-Oxide Production and Vascular Inflammation in Patients With Metabolic Syndrome.

PubMed

Smits, Loek P; Kootte, Ruud S; Levin, Evgeni; Prodan, Andrei; Fuentes, Susana; Zoetendal, Erwin G; Wang, Zeneng; Levison, Bruce S; Cleophas, Maartje C P; Kemper, E Marleen; Dallinga-Thie, Geesje M; Groen, Albert K; Joosten, Leo A B; Netea, Mihai G; Stroes, Erik S G; de Vos, Willem M; Hazen, Stanley L; Nieuwdorp, Max

2018-03-26

Intestinal microbiota have been found to be linked to cardiovascular disease via conversion of the dietary compounds choline and carnitine to the atherogenic metabolite TMAO (trimethylamine-N-oxide). Specifically, a vegan diet was associated with decreased plasma TMAO levels and nearly absent TMAO production on carnitine challenge. We performed a double-blind randomized controlled pilot study in which 20 male metabolic syndrome patients were randomized to single lean vegan-donor or autologous fecal microbiota transplantation. At baseline and 2 weeks thereafter, we determined the ability to produce TMAO from d 6 -choline and d 3 -carnitine (eg, labeled and unlabeled TMAO in plasma and 24-hour urine after oral ingestion of 250 mg of both isotope-labeled precursor nutrients), and fecal samples were collected for analysis of microbiota composition. 18 F-fluorodeoxyglucose positron emission tomography/computed tomography scans of the abdominal aorta, as well as ex vivo peripheral blood mononuclear cell cytokine production assays, were performed. At baseline, fecal microbiota composition differed significantly between vegans and metabolic syndrome patients. With vegan-donor fecal microbiota transplantation, intestinal microbiota composition in metabolic syndrome patients, as monitored by global fecal microbial community structure, changed toward a vegan profile in some of the patients; however, no functional effects from vegan-donor fecal microbiota transplantation were seen on TMAO production, abdominal aortic 18 F-fluorodeoxyglucose uptake, or ex vivo cytokine production from peripheral blood mononuclear cells. Single lean vegan-donor fecal microbiota transplantation in metabolic syndrome patients resulted in detectable changes in intestinal microbiota composition but failed to elicit changes in TMAO production capacity or parameters related to vascular inflammation. URL: http://www.trialregister.nl. Unique identifier: NTR 4338. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Fondaparinux for intra and perioperative anticoagulation in patients with heparin-induced thrombocytopenia candidates for peripheral vascular surgery: Report of 4 cases.

PubMed

Illuminati, Giulio; Calio', Francesco G; Pizzardi, Giulia; Amatucci, Chiara; Masci, Federica; Palumbo, Piergaspare

2016-01-01

Intra and perioperative anticoagulation in patients with heparin induced thrombocytopenia (HIT), candidates for peripheral vascular surgery remains a challenge, as the best alternative to heparin has not yet been established. We evaluated the off-label use of fondaparinux in four patients with HIT, undergoing peripheral vascular surgery procedures. Four patients of whom 3 men of a mean age of 66 years, with proven heparin induced thrombocytopenia (HIT) underwent two axillo-femoral bypasses, one femoro-popliteal bypass and one resection of a splenic artery aneurysm under fondaparinux. No intra or perioperative bleeding or thrombosis of new onset was observed. In the absence of a valid alternative to heparin for intra and perioperative anticoagulation in HIT, several other anticoagulants can be used in an off-label setting. However, no general consensus exist on which should be the one of choice. In this small series fondaparinux appeared to be both safe and effective. These preliminary results seem to justify the off-label use of fondaparinux for intra and perioperative anticoagulation in patients with HIT, candidates for peripheral vascular surgery interventions. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Vascular changes on fluorescein angiography of premature infants with low risk of retinopathy of prematurity after high oxygen exposure.

PubMed

Martinez-Castellanos, Maria Ana; Velez-Montoya, Raul; Price, Kenneth; Henaine-Berra, Andree; García-Aguirre, Gerardo; Morales-Canton, Virgilio; Cernichiaro-Espinosa, Linda Alejandra

2017-01-01

To describe a wide array of peripheral vascular changes using fluorescein angiography in preterm neonates, without high risk characteristics for developing retinopathy of prematurity, that were exposed to high oxygen concentration. Retrospective, two center, case series. Newborns at two different hospitals with ≥1500 g or gestational age of ≥32 weeks, fluorescein angiography performed, and with high oxygen exposure without adequate control were included. 294 infants diagnosed with ROP were analyzed. Only 28 eyes from 14 patients with peripheral vascular abnormalities in older and heavier babies were included. Two distinct type of peripheral vascular changes were observed: group 1 or non-proliferative: areas of capillary non-perfusion along with widespread arteriovenous shunting between adjacent primary vessels, tortuosity of primary vessels, abnormal budding of tertiary vessels and capillaries, abnormal capillary tufts and absence of foveal avascular zone; group 2 or proliferative: all of the characteristics of group 1 plus leakage of dye from the boundary between perfused and non-perfused retina and/or optic disc. Peripheral vascular abnormalities different from retinopathy of prematurity are observed in older than 32 weeks of gestational age, and heavier than 1500 g babies. This makes the authors classify these patients as having a disease caused solely by oxygen dysregulation at the neonatal intensive care unit similarly to the oxygen induced retinopathy in experimental studies.

Quantitative analysis of peripheral vasculitis, ischemia, and vascular leakage in uveitis using ultra-widefield fluorescein angiography.

PubMed

Karampelas, Michael; Sim, Dawn A; Chu, Colin; Carreno, Ester; Keane, Pearse A; Zarranz-Ventura, Javier; Westcott, Mark; Lee, Richard W J; Pavesio, Carlos E

2015-06-01

To investigate the relationships between peripheral vasculitis, ischemia, and vascular leakage in uveitis using ultra-widefield fluorescein angiography (FA). Cross-sectional, consecutive case series. Consecutive ultra-widefield FA images were collected from 82 uveitis patients (82 eyes) in a single center. The extent of peripheral vasculitis, capillary nonperfusion, and vessel leakage were quantified. Parameters included: (1) foveal avascular zone area and macular leakage, (2) peripheral diffuse capillary leakage and ischemia, (3) peripheral vasculitis, and (4) leakage from neovascularization. Central macular thickness measurements were derived with optical coherence tomography. Main outcome measures were correlations between central and peripheral fluorangiographic changes as well as associations between visual function, ultra-widefield FA-derived metrics, and central macular thickness. Although central leakage was associated with peripheral leakage (r = 0.553, P = .001), there was no association between foveal avascular zone size and peripheral ischemia (r = 0.114, P = .324), regardless of the underlying uveitic diagnosis. Peripheral ischemia was, however, correlated to neovascularization-related leakage (r = 0.462, P = .001) and focal vasculitis (r = 0.441, P = .001). Stepwise multiple regression analysis revealed that a poor visual acuity was independently associated with foveal avascular zone size and central macular thickness (R(2)-adjusted = 0.45, P = .001). We present a large cohort of patients with uveitis imaged with ultra-widefield FA and further describe novel methods for quantification of peripheral vascular pathology, in an attempt to identify visually significant parameters. Although we observed that relationships exist between peripheral vessel leakage, vasculitis, and ischemia, it was only macular ischemia and increased macular thickness that were independently associated with a reduced visual acuity. Copyright © 2015 Elsevier Inc. All rights reserved.

Physiologic Pressure and Flow Changes During Parabolic Flight (Pilot Study)

NASA Technical Reports Server (NTRS)

Pantalos, George; Sharp, M. Keith; Mathias, John R.; Hargens, Alan R.; Watenpaugh, Donald E.; Buckey, Jay C.

1999-01-01

The objective of this study was to obtain measurement of cutaneous tissue perfusion central and peripheral venous pressure, and esophageal and abdominal pressure in human test subjects during parabolic flight. Hemodynamic data recorded during SLS-I and SLS-2 missions have resulted in the paradoxical finding of increased cardiac stroke volume in the presence of a decreased central venous pressure (CVP) following entry in weightlessness. The investigators have proposed that in the absence of gravity, acceleration-induced peripheral vascular compression is relieved, increasing peripheral vascular capacity and flow while reducing central and peripheral venous pressure, This pilot study seeks to measure blood pressure and flow in human test subjects during parabolic flight for different postures.

Duplex ultrasound

MedlinePlus

Vascular ultrasound; Peripheral vascular ultrasound ... A duplex ultrasound combines: Traditional ultrasound: This uses sound waves that bounce off blood vessels to create pictures. Doppler ultrasound: This ...

Site-specific association between distal aortic pulse wave velocity and peripheral arterial stenosis severity: a prospective cardiovascular magnetic resonance study.

PubMed

van den Bosch, Harrie C M; Westenberg, Jos J M; Setz-Pels, Wikke; Wondergem, John; Wolterbeek, Ron; Duijm, Lucien E M; Teijink, Joep A W; de Roos, Albert

2015-01-20

Vascular disease expression in one location may not be representative for disease severity in other vascular territories, however, strong correlation between disease expression and severity within the same vascular segment may be expected. Therefore, we hypothesized that aortic stiffening is more strongly associated with disease expression in a vascular territory directly linked to that aortic segment rather than in a more remote segment. We prospectively compared the association between aortic wall stiffness, expressed by pulse wave velocity (PWV), sampled in the distal aorta, with the severity of peripheral arterial occlusive disease (PAOD) as compared to atherosclerotic markers sampled in remote vascular territories such as PWV in the proximal aorta and the normalized wall index (NWI), representing the vessel wall thickness, of the left common carotid artery. Forty-two patients (23 men; mean age 64±10 years) underwent velocity-encoded cardiovascular magnetic resonance (CMR) in the proximal and distal aorta, whole-body contrast-enhanced MR angiography (CE-MRA) and carotid vessel wall imaging with black-blood CMR in the work-up for PAOD. Strength of associations between aortic stiffness, carotid NWI and peripheral vascular stenosis grade were assessed and evaluated with multiple linear regression. Stenosis severity correlated well with PWV in the distal aorta (Pearson rP=0.64, p<0.001, Spearman rS=0.65, p<0.001) but to a lesser extent with PWV in the proximal aorta (rP=0.48, p=0.002, rS=0.22, p=0.18). Carotid NWI was not associated with peripheral stenosis severity (rP=0.17, p=0.28, rS=0.14, p=0.37) nor with PWV in the proximal aorta (rP=0.22, p=0.17) nor in the distal aorta (rP=0.21, p=0.18). Correlation between stenosis severity and distal aortic PWV remained statistically significant after correction for age and gender. Distal aortic wall stiffness is more directly related to peripheral arterial stenosis severity than markers from more remote vascular territories such as proximal aortic wall stiffness or carotid arterial wall thickness. Site-specific evaluation of vascular disease may be required for full vascular risk estimation.

Peripheral arteriovenous fistula as vascular access for long-term chemotherapy.

PubMed

Kovalyov, Oleksiy O; Kostyuk, Oleksandr G; Tkachuk, Tetyana V

To provide long-term vascular access in clinical oncology peripheral forearm veins (up to 95% of patients in Ukraine), central venous access and "complete implanted vascular systems" are used most often. Many oncology patients have contraindications to catheterization of superior vena cava. Besides, exploitation of central veins is associated with potential technical and infectious complications. The aim - to study short-term and long-term results of arteriovenous fistula exploitation as vascular access for continuous anticancer therapy. Peripheral venous bed status in 41 oncology patients taking long-term chemotherapy treatment is analyzed in the article. Doppler sonography, morphologic and immune histochemical analyses were used in the study. Doppler sonography found qualitative and quantitative changes in forearm veins at different time periods after initiation of chemotherapy in the majority of patients. The major morphologic manifestations of venous wall damage were chemical phlebitis, local or extended hardening of venous wall, venous thrombosis and extravasations with necrosis and subsequent paravasal tissue sclerosis. Alternative vascular access created in 12 patients completely met the adequacy criteria (safety, multiple use, longevity, realization of the designed therapy program). The conclusion was made about inapplicability of forearm veins for long-term administration of cytostatic agents. If it is impossible to use central veins, arteriovenous fistula can become an alternative vascular access.

Dynamic MRI for distinguishing high-flow from low-flow peripheral vascular malformations.

PubMed

Ohgiya, Yoshimitsu; Hashimoto, Toshi; Gokan, Takehiko; Watanabe, Shouji; Kuroda, Masayoshi; Hirose, Masanori; Matsui, Seishi; Nobusawa, Hiroshi; Kitanosono, Takashi; Munechika, Hirotsugu

2005-11-01

The purpose of our study was to assess the usefulness of dynamic MRI in distinguishing high-flow vascular malformations from low-flow vascular malformations, which do not need angiography for treatment. Between September 2001 and January 2003, 16 patients who underwent conventional and dynamic MRI had peripheral vascular malformations (six high- and 10 low-flow). The temporal resolution of dynamic MRI was 5 sec. Time intervals between beginning of enhancement of an arterial branch in the vicinity of a lesion in the same slice and the onset of enhancement in the lesion were calculated. We defined these time intervals as "artery-lesion enhancement time." Time intervals between the onset of enhancement in the lesion and the time of the maximal percentage of enhancement above baseline of the lesion within 120 sec were measured. We defined these time intervals as "contrast rise time" of the lesion. Diagnosis of the peripheral vascular malformations was based on angiographic or venographic findings. The mean artery-lesion enhancement time of the high-flow vascular malformations (3.3 sec [range, 0-5 sec]) was significantly shorter than that of the low-flow vascular malformations (8.8 sec [range, 0-20 sec]) (Mann-Whitney test, p < 0.05). The mean maximal lesion enhancement time of the high-flow vascular malformations (5.8 sec [range, 5-10 sec]) was significantly shorter than that of the low-flow vascular malformations (88.4 sec [range, 50-100 sec]) (Mann-Whitney test, p < 0.01). Dynamic MRI is useful for distinguishing high-flow from low-flow vascular malformations, especially when the contrast rise time of the lesion is measured.

X-ray irradiation has positive effects for the recovery of peripheral nerve injury maybe through the vascular smooth muscle contraction signaling pathway.

PubMed

Jiang, Bo; Zhang, Yong; She, Chang; Zhao, Jiaju; Zhou, Kailong; Zuo, Zhicheng; Zhou, Xiaozhong; Wang, Peiji; Dong, Qirong

2017-09-01

It is well known that moderate to high doses of ionizing radiation have a toxic effect on the organism. However, there are few experimental studies on the mechanisms of LDR ionizing radiation on nerve regeneration after peripheral nerve injury. We established the rats' peripheral nerve injury model via repaired Peripheral nerve injury nerve, vascular endothelial growth factor a and Growth associated protein-43 were detected from different treatment groups. We performed transcriptome sequencing focusing on investigating the differentially expressed genes and gene functions between the control group and 1Gy group. Sequencing was done by using high-throughput RNA-sequencing (RNA-seq) technologies. The results showed the 1Gy group to be the most effective promoting repair. RNA-sequencing identified 619 differently expressed genes between control and treated groups. A Gene Ontology analysis of the differentially expressed genes revealed enrichment in the functional pathways. Among them, candidate genes associated with nerve repair were identified. Pathways involved in cell-substrate adhesion, vascular smooth muscle contraction and cell adhesion molecule signaling may be involved in recovery from peripheral nerve injury. Copyright © 2017. Published by Elsevier B.V.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, R.N.

One hundred and fifty patients with coronary artery disease (CAD), 14 (9.3%) of whom had coexisting peripheral vascular disease, underwent bilateral internal mammary arteriography to study the incidence and extent of atherosclerosis in these vessels. Significant atherosclerosis of the internal mammary arteries (IMAs) was present in three patients (2%), of whom one had coexisting peripheral vascular disease. Lesions in the IMAs were found either proximally, close to the origin or distally, around the terminal bifurcation. Six of the 14 patients with peripheral vascular disease (4% of total subjects) had significant atherosclerosis of the brachiocephalic arteries. Atherosclerotic involvement of the IMAmore » is very unusual and rarely interferes with the use of these vessels for coronary bypass. More common, however, is atherosclerosis of the subclavian arteries, a contraindication for IMA grafting if the lesion is proximal to the IMA origin.« less

Vasoreactivity in CADASIL: Comparison to structural MRI and neuropsychology.

PubMed

Moreton, Fiona C; Cullen, Breda; Delles, Christian; Santosh, Celestine; Gonzalez, Rosario L; Dani, Krishna; Muir, Keith W

2018-06-01

Impaired cerebrovascular reactivity precedes histological and clinical evidence of CADASIL in animal models. We aimed to more fully characterise peripheral and cerebral vascular function and reactivity in a cohort of adult CADASIL patients, and explore the associations of these with conventional clinical, imaging and neuropsychological measures. A total of 22 adults with CADASIL gave informed consent to participate in an exploratory study of vascular function in CADASIL. Clinical assessment, comprehensive vascular assessment, MRI and neuropsychological testing were conducted. We measured cerebral vasoreactivity with transcranial Doppler and arterial spin labelling MRI with hypercapnia challenge. Number and volume of lacunes, subcortical hyperintensity volume, microbleeds and normalised brain volume were assessed on MRI. Analysis was exploratory and examined the associations between different markers. Cerebrovascular reactivity measured by ASL correlated with peripheral vasoreactivity measured by flow mediated dilatation. Subjects with ≥5 lacunes were older, with higher carotid intima-media thickness and had impaired cerebral and peripheral vasoreactivity. Subjects with depressive symptoms, disability or delayed processing speed also showed a trend to impaired vasoreactivity. Impaired vasoreactivity and vascular dysfunction may play a significant role in the pathophysiology of CADASIL, and vascular assessments may be useful biomarkers of severity in both longitudinal and clinical trials.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joo, Hyung Joon; Seo, Ha-Rim; Jeong, Hyo Eun

Highlights: • Two distinct vascular progenitor cells are induced from adult peripheral blood. • ECFCs induce vascular structures in vitro and in vivo. • SMPCs augment the in vitro and in vivo angiogenic potential of ECFCs. • Both cell types have synergistic therapeutic potential in ischemic hindlimb model. - Abstract: Proangiogenic cell therapy using autologous progenitors is a promising strategy for treating ischemic disease. Considering that neovascularization is a harmonized cellular process that involves both endothelial cells and vascular smooth muscle cells, peripheral blood-originating endothelial colony-forming cells (ECFCs) and smooth muscle progenitor cells (SMPCs), which are similar to mature endothelialmore » cells and vascular smooth muscle cells, could be attractive cellular candidates to achieve therapeutic neovascularization. We successfully induced populations of two different vascular progenitor cells (ECFCs and SMPCs) from adult peripheral blood. Both progenitor cell types expressed endothelial-specific or smooth muscle-specific genes and markers, respectively. In a protein array focused on angiogenic cytokines, SMPCs demonstrated significantly higher expression of bFGF, EGF, TIMP2, ENA78, and TIMP1 compared to ECFCs. Conditioned medium from SMPCs and co-culture with SMPCs revealed that SMPCs promoted cell proliferation, migration, and the in vitro angiogenesis of ECFCs. Finally, co-transplantation of ECFCs and SMPCs induced robust in vivo neovascularization, as well as improved blood perfusion and tissue repair, in a mouse ischemic hindlimb model. Taken together, we have provided the first evidence of a cell therapy strategy for therapeutic neovascularization using two different types of autologous progenitors (ECFCs and SMPCs) derived from adult peripheral blood.« less

MR imaging of iliofemoral peripheral vascular calcifications using proton density-weighted, in-phase three-dimensional stack-of-stars gradient echo.

PubMed

Ferreira Botelho, Marcos P; Koktzoglou, Ioannis; Collins, Jeremy D; Giri, Shivraman; Carr, James C; Gupta, NavYash; Edelman, Robert R

2017-06-01

The presence of vascular calcifications helps to determine percutaneous access for interventional vascular procedures and has prognostic value for future cardiovascular events. Unlike CT, standard MRI techniques are insensitive to vascular calcifications. In this prospective study, we tested a proton density-weighted, in-phase (PDIP) three-dimensional (3D) stack-of-stars gradient-echo pulse sequence with approximately 1 mm 3 isotropic spatial resolution at 1.5 Tesla (T) and 3T to detect iliofemoral peripheral vascular calcifications and correlated MR-determined lesion volumes with CT angiography (CTA). The study was approved by the Institutional Review Board. The prototype PDIP stack-of-stars pulse sequence was applied in 12 patients with iliofemoral peripheral vascular calcifications who had undergone CTA. Vascular calcifications were well visualized in all subjects, excluding segments near prostheses or stents. The location, size, and shape of the calcifications were similar to CTA. Quantitative analysis showed excellent correlation (r 2  = 0.84; P < 0.0001) between MR- and CT-based measures of calcification volume. In one subject in whom three pulse sequences were compared, PDIP stack-of-stars outperformed cartesian 3D gradient-echo and point-wise encoding time reduction with radial acquisition (PETRA). In this pilot study, a PDIP 3D stack-of-stars gradient-echo pulse sequence with high spatial resolution provided excellent image quality and accurately depicted the location and volume of iliofemoral vascular calcifications. Magn Reson Med 77:2146-2152, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

[Evaluation of mixed biofilm formation between Candida albicans and a variety of bacterial species isolated from peripheral catheters at Tlemcen CHU. First study in Algeria].

PubMed

Seghir, A; Boucherit-Otmani, Z; Boucherit, K; Sari-Belkharroubi, L; Anselme-Bertrand, I

2015-06-01

Mixed-species biofilms constitute a reservoir of infection for a group of bacteria and yeasts that coexist on the same support. Peripheral venous catheters make up a good surface for the attachment of microorganisms that promote biofilm formation and this requires complex strategies for antimicrobial treatments. No such studies on formation mixed biofilms have ever been conducted in Algeria. Therefore, we evaluated the potential for the formation of mixed-species biofilms by Candida albicans and some bacterial species isolated from peripheral vascular catheters at the University Hospital of Tlemcen, in Algeria. The results obtained showed that C. albicans have the potential to form mixed biofilms with three bacteria (Enterobacter cloacae, Bordetella spp. and Serratia liquefaciens) isolated from the same catheter as the yeasts. The amount of biofilms produced varies depending on the species and the composition of the growth medium. Observations by scanning electron microscopy showed that the structure of the mixed biofilm depends on the surface support the biofilm was formed on, and varies with the species. A competition was noted between bacteria and yeasts; it depends on the composition of the medium and its pH, which both play an important role in promoting the dominance of one over the other. Copyright © 2015. Published by Elsevier Masson SAS.

Vascular access in lipoprotein apheresis: a retrospective analysis from the UK's largest lipoprotein apheresis centre.

PubMed

Doherty, Daniel J; Pottle, Alison; Malietzis, George; Hakim, Nadey; Barbir, Mahmoud; Crane, Jeremy S

2018-01-01

Lipoprotein apheresis (LA) has proven to be an effective, safe and life-saving therapy. Vascular access is needed to facilitate this treatment but has recognised complications. Despite consistency in treatment indication and duration there are no guidelines in place. The aim of this study is to characterise vascular access practice at the UK's largest LA centre and forward suggestions for future approaches. A retrospective analysis of vascular access strategies was undertaken in all patients who received LA treatment in the low-density lipoprotein (LDL) Apheresis Unit at Harefield Hospital (Middlesex, UK) from November 2000 to March 2016. Fifty-three former and current patients underwent 4260 LA treatments. Peripheral vein cannulation represented 79% of initial vascular access strategies with arteriovenous (AV) fistula use accounting for 15%. Last used method of vascular access was peripheral vein cannulation in 57% versus AV fistula in 32%. Total AV fistula failure rate was 37%. Peripheral vein cannulation remains the most common method to facilitate LA. Practice trends indicate a move towards AV fistula creation; the favoured approach receiving support from the expert body in this area. AV fistula failure rate is high and of great concern, therefore we suggest the implementation of upper limb ultrasound vascular mapping in all patients who meet treatment eligibility criteria. We encourage close ties between apheresis units and specialist surgical centres to facilitate patient counselling and monitoring. Further prospective data regarding fistula failure is needed in this expanding treatment field.

Inter-arm systolic blood pressure differences, relations with future vascular events and mortality in patients with and without manifest vascular disease.

PubMed

Kranenburg, Guido; Spiering, Wilko; de Jong, Pim A; Kappelle, L Jaap; de Borst, Gert Jan; Cramer, Maarten J; Visseren, Frank L J; Aboyans, Victor; Westerink, Jan

2017-10-01

Inter-arm systolic blood pressure difference (SBPD) is an easily obtained patient characteristic which relates to vascular disease. We aimed to identify determinants of large inter-arm SBPD and to investigate the relation between inter-arm SBPD and vascular events in patients with and without manifest vascular disease. In a cohort of 7344 patients with manifest vascular disease or vascular risk factors alone enrolled in the Second Manifestations of ARTerial disease (SMART) study, single bilateral non-simultaneous blood pressure measurements were performed. Logistic and Cox regression was used to identify determinants of large inter-arm SBPD (≥15mmHg) and to investigate the relation between inter-arm SBPD and vascular events (composite of non-fatal myocardial infarction, stroke, and vascular mortality) and all-cause mortality. In all patients the median inter-arm SBPD was 7mmHg (IQR 3-11) and 1182 (16%) patients had inter-arm SBPD ≥15mmHg. Higher age, higher systolic blood pressure, diabetes mellitus, peripheral artery disease, carotid artery stenosis, higher carotid intima-media thickness, and lower ankle-brachial indices were related to large inter-arm SBPD (≥15mmHg). Each 5mmHg increase in inter-arm SBPD was related to a 12% higher risk of vascular events in patients without manifest vascular disease (HR 1.12; 95% CI 1.00-1.27), whereas no relation was apparent in patients with manifest vascular disease (HR 0.98; 95% CI 0.93-1.04, interaction p-value 0.036). Inter-arm SBPD was not related to all-cause mortality (HR 1.05; 95% CI 0.93-1.19). Inter-arm SBPD relates to a higher risk of vascular events in patients without manifest vascular disease, whereas this relation is not apparent in patients with manifest vascular disease. Copyright © 2017 Elsevier B.V. All rights reserved.

[Ischemic origin of diabetic foot disease. Epidemiology, difficulties of diagnosis, options for prevention and revascularization].

PubMed

Kolossváry, Endre; Bánsághi, Zoltán; Szabó, Gábor Viktor; Járai, Zoltán; Farkas, Katalin

2017-02-01

"Diabetic foot" as definition covers a multifactorial clinical condition. According to the recent epidemiological data, the role of lower limb ischemia is getting more influential over other pathological causes, like neuropathy, infections and bone or soft tissue deformity. In diabetes, vascular disease leads to increased risk for leg ulcers and minor or major amputations. The traditional diagnostic tools for recognition of peripheral arterial disease have limited value because of diabetes specific clinical manifestations. Available vascular centers with special expertise and diagnostic tools are the prerequisite for efficient diagnosis supporting timely recognition of peripheral arterial disease. In course of treatment of diabetic foot with ischemic origin, beyond effective medical treatment revascularization (open vascular surgery or endovascular procedures) has paramount importance for prevention of limb loss. Vascular teams of vascular specialists, vascular surgeons and interventional radiologist in dedicated centers in multidisciplinary cooperation with other professions represent public health issue in effective prevention. Orv. Hetil., 2017, 158(6), 203-211.

The effect of hypnosis on pain and peripheral blood flow in sickle-cell disease: a pilot study

PubMed Central

Bhatt, Ravi R; Martin, Sarah R; Evans, Subhadra; Lung, Kirsten; Coates, Thomas D; Zeltzer, Lonnie K; Tsao, Jennie C

2017-01-01

Background Vaso-occlusive pain crises (VOCs) are the “hallmark” of sickle-cell disease (SCD) and can lead to sympathetic nervous system dysfunction. Increased sympathetic nervous system activation during VOCs and/or pain can result in vasoconstriction, which may increase the risk for subsequent VOCs and pain. Hypnosis is a neuromodulatory intervention that may attenuate vascular and pain responsiveness. Due to the lack of laboratory-controlled pain studies in patients with SCD and healthy controls, the specific effects of hypnosis on acute pain-associated vascular responses are unknown. The current study assessed the effects of hypnosis on peripheral blood flow, pain threshold, tolerance, and intensity in adults with and without SCD. Subjects and methods Fourteen patients with SCD and 14 healthy controls were included. Participants underwent three laboratory pain tasks before and during a 30-minute hypnosis session. Peripheral blood flow, pain threshold, tolerance, and intensity before and during hypnosis were examined. Results A single 30-minute hypnosis session decreased pain intensity by a moderate amount in patients with SCD. Pain threshold and tolerance increased following hypnosis in the control group, but not in patients with SCD. Patients with SCD exhibited lower baseline peripheral blood flow and a greater increase in blood flow following hypnosis than controls. Conclusion Given that peripheral vasoconstriction plays a role in the development of VOC, current findings provide support for further laboratory and clinical investigations of the effects of cognitive–behavioral neuromodulatory interventions on pain responses and peripheral vascular flow in patients with SCD. Current results suggest that hypnosis may increase peripheral vasodilation during both the anticipation and experience of pain in patients with SCD. These findings indicate a need for further examination of the effects of hypnosis on pain and vascular responses utilizing a randomized controlled trial design. Further evidence may help determine unique effects of hypnosis and potential benefits of integrating cognitive–behavioral neuromodulatory interventions into SCD treatment. PMID:28769584

Neurovascular patterning cues and implications for central and peripheral neurological disease

PubMed Central

Gamboa, Nicholas T.; Taussky, Philipp; Park, Min S.; Couldwell, William T.; Mahan, Mark A.; Kalani, M. Yashar S.

2017-01-01

The highly branched nervous and vascular systems run along parallel trajectories throughout the human body. This stereotyped pattern of branching shared by the nervous and vascular systems stems from a common reliance on specific cues critical to both neurogenesis and angiogenesis. Continually emerging evidence supports the notion of later-evolving vascular networks co-opting neural molecular mechanisms to ensure close proximity and adequate delivery of oxygen and nutrients to nervous tissue. As our understanding of these biologic pathways and their phenotypic manifestations continues to advance, identification of where pathways go awry will provide critical insight into central and peripheral nervous system pathology. PMID:28966815

Major Adverse Limb Events and Mortality in Patients With Peripheral Artery Disease: The COMPASS Trial.

PubMed

Anand, Sonia S; Caron, Francois; Eikelboom, John W; Bosch, Jackie; Dyal, Leanne; Aboyans, Victor; Abola, Maria Teresa; Branch, Kelley R H; Keltai, Katalin; Bhatt, Deepak L; Verhamme, Peter; Fox, Keith A A; Cook-Bruns, Nancy; Lanius, Vivian; Connolly, Stuart J; Yusuf, Salim

2018-05-22

Patients with lower extremity peripheral artery disease (PAD) are at increased risk of major adverse cardiovascular events (MACE) and major adverse limb events (MALE). There is limited information on the prognosis of patients who experience MALE. Among participants with lower extremity PAD, this study investigated: 1) if hospitalizations, MACE, amputations, and deaths are higher after the first episode of MALE compared with patients with PAD who do not experience MALE; and 2) the impact of treatment with low-dose rivaroxaban and aspirin compared with aspirin alone on the incidence of MALE, peripheral vascular interventions, and all peripheral vascular outcomes over a median follow-up of 21 months. We analyzed outcomes in 6,391 patients with lower extremity PAD who were enrolled in the COMPASS (Cardiovascular Outcomes for People Using Anticoagulation Strategies) trial. COMPASS was a randomized, double-blind placebo-controlled study of low-dose rivaroxaban and aspirin combination or rivaroxaban alone compared with aspirin alone. MALE was defined as severe limb ischemia leading to an intervention or major vascular amputation. A total of 128 patients experienced an incident of MALE. After MALE, the 1-year cumulative risk of a subsequent hospitalization was 61.5%; for vascular amputations, it was 20.5%; for death, it was 8.3%; and for MACE, it was 3.7%. The MALE index event significantly increased the risk of experiencing subsequent hospitalizations (hazard ratio [HR]: 7.21; p < 0.0001), subsequent amputations (HR: 197.5; p < 0.0001), and death (HR: 3.23; p < 0.001). Compared with aspirin alone, the combination of rivaroxaban 2.5 mg twice daily and aspirin lowered the incidence of MALE by 43% (p = 0.01), total vascular amputations by 58% (p = 0.01), peripheral vascular interventions by 24% (p = 0.03), and all peripheral vascular outcomes by 24% (p = 0.02). Among individuals with lower extremity PAD, the development of MALE is associated with a poor prognosis, making prevention of this condition of utmost importance. The combination of rivaroxaban 2.5 mg twice daily and aspirin significantly lowered the incidence of MALE and the related complications, and this combination should be considered as an important therapy for patients with PAD. (Cardiovascular Outcomes for People Using Anticoagulation Strategies [COMPASS]; NCT01776424). Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Reproducibility and repeatability of peripheral microvascular assessment using iontophoresis in conjunction with laser Doppler imaging.

PubMed

Jadhav, Sachin; Sattar, Naveed; Petrie, John R; Cobbe, Stuart M; Ferrell, William R

2007-09-01

Interrogation of peripheral vascular function is increasingly recognized as a noninvasive surrogate marker for coronary vascular function and carries with it important prognostic information regarding future cardiovascular risk. Laser Doppler imaging (LDI) is a completely noninvasive method for looking at peripheral microvascular function. We sought to look at reproducibility and repeatability of LDI-derived assessment of peripheral microvascular function between arms and 8 weeks apart. We used LDI in conjunction with iontophoretic application of ACh and SNP to look at endothelium-dependent and -independent microvascular function, respectively, in a mixture of women with cardiac syndrome X and healthy volunteers. We looked at variation between arms (n = 40) and variation at 8 weeks apart (n = 22). When measurements were corrected for skin resistance, there was nonsignificant variation between arms for ACh (2.7%) and SNP (3.8%) and nonsignificant temporal variation for ACh (3.5%) and SNP (4.7%). Construction of Bland-Altman plots reinforce that measurements have good repeatability. Elimination of the baseline perfusion response had deleterious effects on repeatability. LDI can be used to assess peripheral vascular response with good repeatability as long as measurements are corrected for skin resistance, which affects drug delivery. This has important implications for the future use of LDI.

Whole-Mount Adult Ear Skin Imaging Reveals Defective Neuro-Vascular Branching Morphogenesis in Obese and Type 2 Diabetic Mouse Models.

PubMed

Yamazaki, Tomoko; Li, Wenling; Yang, Ling; Li, Ping; Cao, Haiming; Motegi, Sei-Ichiro; Udey, Mark C; Bernhard, Elise; Nakamura, Takahisa; Mukouyama, Yoh-Suke

2018-01-11

Obesity and type 2 diabetes are frequently associated with peripheral neuropathy. Though there are multiple methods for diagnosis and analysis of morphological changes of peripheral nerves and blood vessels, three-dimensional high-resolution imaging is necessary to appreciate the pathogenesis with an anatomically recognizable branching morphogenesis and patterning. Here we established a novel technique for whole-mount imaging of adult mouse ear skin to visualize branching morphogenesis and patterning of peripheral nerves and blood vessels. Whole-mount immunostaining of adult mouse ear skin showed that peripheral sensory and sympathetic nerves align with large-diameter blood vessels. Diet-induced obesity (DIO) mice exhibit defective vascular smooth muscle cells (VSMCs) coverage, while there is no significant change in the amount of peripheral nerves. The leptin receptor-deficient db/db mice, a severe obese and type 2 diabetic mouse model, exhibit defective VSMC coverage and a large increase in the amount of smaller-diameter nerve bundles with myelin sheath and unmyelinated nerve fibers. Interestingly, an increase in the amount of myeloid immune cells was observed in the DIO but not db/db mouse skin. These data suggest that our whole-mount imaging method enables us to investigate the neuro-vascular and neuro-immune phenotypes in the animal models of obesity and diabetes.

Short-term outcomes of excisional atherectomy in lower limb arterial disease.

PubMed

Werner-Gibbings, Keagan; Dubenec, Steven

2017-06-01

Endovascular interventions are increasingly utilized in managing occlusive peripheral vascular disease. Angioplasty and stenting remain the mainstay of endovascular management; however, newer treatment modalities such as excisional atherectomy provide the clinician with additional treatment options. While demonstrating promising results in available trials, a paucity of data exist regarding peripheral atherectomy. The purpose of this retrospective clinical study was to assess the efficacy and safety of excisional atherectomy with the TurboHawk atherectomy device (Covidien/ev3, Plymouth, MN, USA) in the treatment of lower limb peripheral vascular disease and to evaluate the learning curve involved in the institution of a new treatment modality. A retrospective analysis was performed on all patients undergoing atherectomy for symptomatic lower limb peripheral vascular disease by a single clinician between November 2011 and June 2013. Forty-seven vessels on 28 legs in 24 patients were treated during the period. Atherectomy was possible in 98% of cases. The 6- and 12-month primary patency was 72.6 and 58.9%, respectively. The primary-assisted patency was 93.2% at 6 months and 74.6% at 12 months. There were significantly greater patency rates in the TransAtlantic Inter-Society Consensus A + B lesions and a non-significant trend towards improved patency rates in claudicants versus critical limb ischaemia. There were four instances of embolization and four cases of dissection. Excisional atherectomy provides a further option for the minimally invasive management of peripheral vascular disease. It has similar patency rates to established endovascular therapies and should be considered among the treatment options in patients with favourable pathology. © 2014 Royal Australasian College of Surgeons.

Glycemic control and macrovascular disease in types 1 and 2 diabetes mellitus: Meta-analysis of randomized trials.

PubMed

Stettler, Christoph; Allemann, Sabin; Jüni, Peter; Cull, Carole A; Holman, Rury R; Egger, Matthias; Krähenbühl, Stephan; Diem, Peter

2006-07-01

Uncertainty persists concerning the effect of improved long-term glycemic control on macrovascular disease in diabetes mellitus (DM). We performed a systematic review and meta-analysis of randomized controlled trials comparing interventions to improve glycemic control with conventional treatment in type 1 and type 2 diabetes. Outcomes included the incidence rate ratios for any macrovascular event, cardiac events, stroke, and peripheral arterial disease, and the number needed to treat intensively during 10 years to prevent one macrovascular event. The analysis was based on 8 randomized comparisons including 1800 patients with type 1 DM (134 macrovascular events, 40 cardiac events, 88 peripheral vascular events, 6 cerebrovascular events, 11293 person-years of follow-up) and 6 comparisons including 4472 patients with type 2 DM (1587 macrovascular events, 1197 cardiac events, 87 peripheral vascular events, 303 cerebrovascular events, 43607 person-years). Combined incidence rate ratios for any macrovascular event were 0.38 (95% CI 0.26-0.56) in type 1 and 0.81 (0.73-0.91) in type 2 DM. In type 1 DM, effect was mainly based on reduction of cardiac and peripheral vascular events and, in type 2 DM, due to reductions in stroke and peripheral vascular events. Effects appear to be particularly important in younger patients with shorter duration of diabetes. Our data suggest that attempts to improve glycemic control reduce the incidence of macrovascular events both in type 1 and type 2 DM. In absolute terms, benefits are comparable, although effects on specific manifestations of macrovascular disease differ.

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.

Avascular Retinal Findings in a Child With Achondroplasia.

PubMed

Hua, Hong-Uyen T; Tran, Kimberly D; Medina, Carlos A; Fallas, Brenda; Negron, Cathy; Berrocal, Audina M

2017-03-01

The authors present clinical and angiographic findings in a 12-year-old girl with achondroplasia who presented with bilateral retinal peripheral nonperfusion and unilateral rhegmatogenous retinal detachment, which has not been previously described in achondroplasia. This report contributes incremental knowledge regarding aberrant retinal vascular phenomena observed in pediatric disease states and implicates the possible role of mutations in the FGFR3 gene in peripheral vascular abnormalities. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:272-274.]. Copyright 2017, SLACK Incorporated.

Clinical use of closed-system safety peripheral intravenous cannulas.

PubMed

Barton, Andrew

2018-04-26

Peripheral intravenous (IV) cannulas are the quickest and most effective way of gaining venous vascular access and administering IV therapy. Closed-system peripheral IV cannulas have been shown to be safe and more reliable than open, non-valved peripheral cannulas in clinical practice. This article introduces the Smiths Medical DeltaVen closed-system peripheral IV cannula and includes three case studies describing its use in clinical practice and associated patient outcomes.

Impact of previous vascular burden on in-hospital and long-term mortality in patients with ST-segment elevation myocardial infarction.

PubMed

Consuegra-Sánchez, Luciano; Melgarejo-Moreno, Antonio; Galcerá-Tomás, José; Alonso-Fernández, Nuria; Díaz-Pastor, Angela; Escudero-García, Germán; Jaulent-Huertas, Leticia; Vicente-Gilabert, Marta

2014-06-01

Patients with a current acute coronary syndrome and previous ischemic heart disease, peripheral arterial disease, and/or cerebrovascular disease are reported to have a poorer outcome than those without these previous conditions. It is uncertain whether this association with outcome is observed at long-term follow-up. Prospective observational study, including 4247 patients with ST-segment elevation myocardial infarction. Detailed clinical data and information on previous ischemic heart disease, peripheral arterial disease, and cerebrovascular disease ("vascular burden") were recorded. Multivariate models were performed for in-hospital and long-term (median, 7.2 years) all-cause mortality. One vascular territory was affected in 1131 (26.6%) patients and ≥ 2 territories in 221 (5.2%). The total in-hospital mortality rate was 12.3% and the long-term incidence density was 3.5 deaths per 100 patient-years. A background of previous ischemic heart disease (odds ratio = 0.83; P = .35), peripheral arterial disease (odds ratio = 1.30; P = .34), or cerebrovascular disease (stroke) (odds ratio = 1.15; P = .59) was not independently predictive of in-hospital death. In an adjusted model, previous cerebrovascular disease and previous peripheral arterial disease were both predictors of mortality at long-term follow-up (hazard ratio = 1.57; P < .001; and hazard ratio = 1.34; P = .001; respectively). Patients with ≥ 2 diseased vascular territories showed higher long-term mortality (hazard ratio = 2.35; P < .001), but not higher in-hospital mortality (odds ratio = 1.07; P = .844). In patients with a diagnosis of ST-segment elevation acute myocardial infarction, the previous vascular burden determines greater long-term mortality. Considered individually, previous cerebrovascular disease and peripheral arterial disease were predictors of mortality at long-term after hospital discharge. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.

Premise and promise of mesenchymal stem cell-based therapies in clinical vascularized composite allotransplantation.

PubMed

Schweizer, Riccardo; Gorantla, Vijay S; Plock, Jan A

2015-12-01

Over the past decade, clinical vascularized composite allotransplantation (VCA) has enabled functional and quality of life restoration in a wide range of indications secondary to devastating tissue loss. However, the spectre of toxicity and long-term complications of chronic immunosuppression has curtailed the momentum of VCA. This study summarizes the literature evidence behind successful mesenchymal stem cell (MSC)-based cell therapies highlighting their multipronged immunomodulatory, restorative and regenerative characteristics with special emphasis towards VCA applications. Experimental and clinical studies in solid organs and VCA have confirmed that MSCs facilitate immunosuppression-free allograft survival or tolerance, stimulate peripheral nerve regeneration, attenuate ischaemia-reperfusion injury, and improve tissue healing after surgery. It has been hypothesized that MSC-induced long-term operational tolerance in experimental VCA is mediated by induction of mixed donor-specific chimerism and regulatory T-cell mechanisms. All these characteristics of MSCs could thus help expand the scope and clinical feasibility of VCA. Cellular therapies, especially those focusing on MSCs, are emerging in solid organ transplantation including VCA. Although some clinical trials have begun to assess the effects of MSCs in solid organ transplantation, much scientific domain remains uncharted, especially for VCA.

Association of a difference in systolic blood pressure between arms with vascular disease and mortality: a systematic review and meta-analysis.

PubMed

Clark, Christopher E; Taylor, Rod S; Shore, Angela C; Ukoumunne, Obioha C; Campbell, John L

2012-03-10

Differences in systolic blood pressure (SBP) of 10 mm Hg or more or 15 mm Hg or more between arms have been associated with peripheral vascular disease and attributed to subclavian stenosis. We investigated whether an association exists between this difference and central or peripheral vascular disease, and mortality. We searched Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, Cochrane, and Medline In Process databases for studies published before July, 2011, showing differences in SBP between arms, with data for subclavian stenosis, peripheral vascular disease, cerebrovascular disease, cardiovascular disease, or survival. We used random effects meta-analysis to combine estimates of the association between differences in SBP between arms and each outcome. We identified 28 eligible studies for review, 20 of which were included in our meta-analyses. In five invasive studies using angiography, mean difference in SBP between arms was 36·9 mm Hg (95% CI 35·4-38·4) for proven subclavian stenosis (>50% occlusion), and a difference of 10 mm Hg or more was strongly associated with subclavian stenosis (risk ratio [RR] 8·8, 95% CI 3·6-21·2). In non-invasive studies, pooled findings showed that a difference of 15 mm Hg or more was associated with peripheral vascular disease (nine cohorts; RR 2·5, 95% CI 1·6-3·8; sensitivity 15%, 9-23; specificity 96%, 94-98); pre-existing cerebrovascular disease (five cohorts; RR 1·6, 1·1-2·4; sensitivity 8%, 2-26; specificity 93%, 86-97); and increased cardiovascular mortality (four cohorts; hazard ratio [HR] 1·7, 95% CI 1·1-2·5) and all-cause mortality (HR 1·6, 1·1-2·3). A difference of 10 mm Hg or higher was associated with peripheral vascular disease (five studies; RR 2·4, 1·5-3·9; sensitivity 32%, 23-41; specificity 91%, 86-94). A difference in SBP of 10 mm Hg or more, or of 15 mm Hg or more, between arms might help to identify patients who need further vascular assessment. A difference of 15 mm Hg or more could be a useful indicator of risk of vascular disease and death. Royal College of General Practitioners, South West GP Trust, and Peninsula Collaboration for Leadership in Applied Health Research and Care. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

Ultrawide-field Fluorescein Angiography for Evaluation of Diabetic Retinopathy

PubMed Central

Kong, Mingui; Lee, Mee Yon

2012-01-01

Purpose To investigate the advantages of ultrawide-field fluorescein angiography (FA) over the standard fundus examination in the evaluation of diabetic retinopathy (DR). Methods Ultrawide-field FAs were obtained in 118 eyes of 59 diabetic patients; 11 eyes with no DR, 71 eyes with nonproliferative diabetic retinopathy (NPDR), and 36 eyes with proliferative diabetic retinopathy (PDR), diagnosed by the standard method. The presence of peripheral abnormal lesions beyond the standard seven fields was examined. Results Ultrawide-field FA images demonstrated peripheral microaneurysms in six (54.5%) of 11 eyes with no DR and all eyes with moderate to severe NPDR and PDR. Peripheral retinal neovascularizations were detected in three (4.2%) of 71 eyes with NPDR and in 13 (36.1%) of 36 eyes with PDR. Peripheral vascular nonperfusion and vascular leakage were found in two-thirds of eyes with severe NPDR and PDR. Conclusions Ultrawide-field FA demonstrates peripheral lesions beyond standard fields, which can allow early detection and a close evaluation of DR. PMID:23204797

Comprehensive assessment of impaired peripheral and coronary artery endothelial functions in smokers using brachial artery ultrasound and oxygen-15-labeled water PET.

PubMed

Ochi, Noriki; Yoshinaga, Keiichiro; Ito, Yoichi M; Tomiyama, Yuuki; Inoue, Mamiko; Nishida, Mutsumi; Manabe, Osamu; Shibuya, Hitoshi; Shimizu, Chikara; Suzuki, Eriko; Fujii, Satoshi; Katoh, Chietsugu; Tamaki, Nagara

2016-10-01

Comprehensive evaluation of endothelium-dependent and endothelium-independent vascular functions in peripheral arteries and coronary arteries in smokers has never been performed previously. Through the use of brachial artery ultrasound and oxygen-15-labeled water positron emission tomography (PET), we sought to investigate peripheral and coronary vascular dysfunctions in smokers. Eight smokers and 10 healthy individuals underwent brachial artery ultrasound at rest, during reactive hyperemia [250mmHg cuff occlusion (flow-mediated dilatation (FMD)], and following sublingual nitroglycerin (NTG) administration. Myocardial blood flow (MBF) was assessed through O-15-labeled water PET at rest, during adenosine triphosphate (ATP) administration, and during a cold pressor test (CPT). Through ultrasound, smokers were shown to have significantly reduced %FMD compared to controls (6.62±2.28% vs. 11.29±2.75%, p=0.0014). As assessed by O-15-labeled water PET, smokers were shown to have a significantly lower CPT response than were controls (21.1±9.5% vs. 50.9±16.9%, p=0.0004). There was no relationship between %FMD and CPT response (r=0.40, p=0.097). Endothelium-independent vascular dilatation was similar for both groups in terms of coronary flow reserve with PET (p=0.19). Smokers tended to have lower %NTG in the brachial artery (p=0.055). Smokers exhibited impaired coronary endothelial function as well as peripheral brachial artery endothelial function. In addition, there was no correlation between PET and ultrasound measurements, possibly implying that while smokers may have systemic vascular endothelial dysfunction, the characteristics of that dysfunction may be different in peripheral arteries and coronary arteries. Copyright © 2016. Published by Elsevier Ltd.

Pruning of the Pulmonary Vasculature in Asthma: The SARP Cohort.

PubMed

Ash, Samuel Y; Rahaghi, Farbod N; Come, Carolyn E; Ross, James C; Colon, Alysha G; Cardet-Guisasola, Juan Carlos; Dunican, Eleanor M; Bleecker, Eugene R; Castro, Mario; Fahy, John V; Fain, Sean B; Gaston, Benjamin M; Hoffman, Eric A; Jarjour, Nizar N; Mauger, David T; Wenzel, Sally E; Levy, Bruce D; San Jose Estepar, Raul; Israel, Elliot; Washko, George R

2018-04-19

Loss of the peripheral pulmonary vasculature, termed vascular pruning, is associated with disease severity in patients with chronic obstructive pulmonary disease. To determine if pulmonary vascular pruning is associated with asthma severity and exacerbations. We measured the total pulmonary blood vessel volume (TBV) and the blood vessel volume of vessels less than 5mm2 in cross sectional area (BV5) and of vessels less than 10mm2 (BV10) in cross sectional area on non-contrast computed tomographic scans of participants from the Severe Asthma Research Program. Lower values of the BV5 to TBV ratio (BV5/TBV) and the BV10 to TBV ratio (BV10/TBV) represented vascular pruning (loss of the peripheral pulmonary vasculature). Compared to healthy controls, severe asthmatics had more pulmonary vascular pruning. Among asthmatics, those with poor asthma control had more pruning than those well-controlled disease. Pruning of the pulmonary vasculature was also associated with lower percent predicted forced expiratory volume in one second and forced vital capacity, greater peripheral and sputum eosinophilia and higher bronchoalveolar lavage SAA/LXA4, but not with low attenuation area or with sputum neutrophilia. Compared with individuals with less pruning, individuals with the most vascular pruning had a 150% greater odds of reporting an asthma exacerbation (OR 2.50; CI: 1.05, 5.98; p=0.039 for BV10/TBV), and reported 45% more asthma exacerbations during follow-up (IRR 1.45; CI: 1.02, 2.06; p=0.036 for BV10/TBV). Pruning of the peripheral pulmonary vasculature is associated with asthma severity, control and exacerbations, as well as with lung function and eosinophilia.

Endothelial health in childhood acute lymphoid leukemia survivors: pilot evaluation with peripheral artery tonometry.

PubMed

Ruble, Kathy; Davis, Catherine L; Han, Hae-Ra

2015-03-01

Childhood cancer survivors are a growing population at risk for poor cardiac outcomes. Acute lymphoid leukemia (ALL) survivors are among those at increased risk of cardiovascular complications. Early identification of impaired vascular health may allow for interventions to improve these outcomes. The purpose of this study was to evaluate vascular health using peripheral artery tonometry in ALL survivors and compare results with healthy siblings. Sixteen ALL survivor, healthy sibling pairs, aged 8 to 20 years, were evaluated for vascular health and cardiovascular risk factors (body mass index, central adiposity, blood pressure, and fitness). One-tailed paired t test was used to compare the groups. Survivors were similar to siblings in cardiovascular risk measures but had poorer vascular health as measured by reactive hyperemia index (survivor RHI 1.54 vs. sibling 1.77; P=0.0474). This study reveals that even among survivors who are comparable to their healthy siblings in other traditional cardiovascular risks, there is evidence of poorer vascular health.

Mechanical Properties of High Entropy Alloy Al0.1CoCrFeNi for Peripheral Vascular Stent Application.

PubMed

Alagarsamy, Karthik; Fortier, Aleksandra; Komarasamy, Mageshwari; Kumar, Nilesh; Mohammad, Atif; Banerjee, Subhash; Han, Hai-Chao; Mishra, Rajiv S

2016-12-01

High entropy alloys (HEAs) are new class of metallic materials with five or more principal alloying elements. Due to this distinct concept of alloying, the HEAs exhibit unique properties compared to conventional alloys. The outstanding properties of HEAs include increased strength, superior wear resistance, high temperature stability, increased fatigue properties, good corrosion, and oxidation resistance. Such characteristics of HEAs have generated significant interest among the scientific community. However, their applications are yet to be explored. This paper discusses the mechanical behavior and microstructure of Al 0.1 CoCrFeNi HEA subjected to thermo-mechanical processing, and its potential application in peripheral vascular stent implants that are prone to high failure rates. Results show that Al 0.1 CoCrFeNi alloy possesses characteristics that compare well against currently used stent materials and it can potentially find use in peripheral vascular stent implants and extend their life-cycle.

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

PubMed

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

2015-12-01

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

Regulatory T Cell-Enriching Microparticles for Promoting Vascularized Composite Allotransplant Survival

DTIC Science & Technology

2016-10-01

AWARD NUMBER: W81XWH-15-1-0244 TITLE: Regulatory T Cell-Enriching Microparticles for Promoting Vascularized Composite Allotransplant Survival...2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Regulatory T Cell-Enriching Microparticles for Promoting Vascularized Composite Allotransplant Survival...observed effects these particles have on allograft survival. Key Words CTA Composite Tissue Allotransplantation VCA Vascularized Composite

Peripheral Vascular Disease: The Beneficial Effect of Exercise in Peripheral Vascular Diseases Based on Clinical Trials.

PubMed

Elnady, Basant M; Saeed, Ayman

2017-01-01

Intermittent claudication (IC) due to peripheral artery diseases (PAD) is one of the disabling disease that can affect quality of life (QOL) and functional status of capacity. It is characterized by cramping pain which develops with exercise and eliminated by rest secondary to decrease blood flow to the muscles. The annual incidence rate is increased with age. Exercise rehabilitation has a great impact in improving the functional capacity and prevent the functional disability. The available evidences from current studies have showed that exercise therapy is considered the primary treatment in PAD, which in consequently improves the QOL. In this chapter we will illustrate the current available evidences which support exercise benefit and outcomes in PAD with IC.

Essential Thrombocythaemia and Peripheral Gangrene

PubMed Central

Preston, F. E.; Emmanuel, I. G.; Winfield, D. A.; Malia, R. G.

1974-01-01

Six patients are described in whom gangrene of one or more toes occurred as the presenting feature of essential thrombocythaemia. Spontaneous platelet aggregation was observed in platelet-rich plasma from four patients and platelet aggregation after the addition of adenosine diphosphate and collagen was highly abnormal in samples from all six. All of the patients described dramatic relief of pain within six hours of ingestion of aspirin and this coincided with disappearance of the spontaneous platelet aggregation and collagen-induced platelet aggregation. Treatment with phosphorus-32 corrected the platelet count and there were no further recurrences of peripheral vascular disease. Platelet function tests performed at the time all gave normal results. It is concluded that essential thrombocythaemia is an important and treatable cause of peripheral vascular disease. PMID:4472103

[Infectious risk related to the formation of multi-species biofilms (Candida - bacteria) on peripheral vascular catheters].

PubMed

Seghir, A; Boucherit-Otmani, Z; Sari-Belkharroubi, L; Boucherit, K

2017-03-01

The Candida yeasts are the fourth leading cause of death from systemic infections, the risk may increase when the infection also involves bacteria. Yeasts and bacteria can adhere to medical implants, such as peripheral vascular catheters, and form a multicellular structures called "mixed biofilms" more resistant to antimicrobials agents. However, the formation of mixed biofilms on implants leads to long-term persistent infections because they can act as reservoirs of pathogens that have poorly understood interactions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Splinter haemorrhages, Osler's nodes, Janeway lesions and Roth spots: the peripheral stigmata of endocarditis.

PubMed

Sethi, Karishma; Buckley, Jim; de Wolff, Jacob

2013-09-01

Infective endocarditis is a serious endo-vascular infection, potentially affecting not only native heart valves, but also intra-vascularly implanted foreign materials such as valvular prostheses and pacemaker electrodes (Westphal et al, 2009).

Routine use of PICO dressings may reduce overall groin wound complication rates following peripheral vascular surgery.

PubMed

Fleming, C A; Kuteva, M; O'Hanlon, K; O'Brien, G; McGreal, G

2018-05-01

Approximately 19% of morbidity in peripheral vascular surgery is attributable to wound complications, which can result in delayed healing, and also arterial or graft infection leading to limb loss and even mortality in extreme cases. To determine whether groin wound complications were reduced following the routine introduction of PICO negative pressure wound therapy dressings in patients who underwent peripheral vascular surgery. Patients who underwent peripheral vascular surgery from 2011 to 2016 were identified and divided into PICO and non-PICO groups. Patient, procedure and wound characteristics were tabulated and analysed. Patients were followed-up for at least six weeks postoperatively. Wound complication rates, infection confirmed by microbiology, and requirement for re-admission due to wound complications were noted. Basic cost analysis was performed. In total, 151 patients were analysed (N = 73 PICO, N = 78 non-PICO). No difference in age (P = 0.862), body mass index (P = 0.673), diabetes (P = 0.339), pre-operative albumin (P = 0.196), use of drain (P = 0.343) and history of meticillin-resistant Staphylococcus aureus (P = 0.281) was observed between groups. The PICO group contained more smokers than the non-PICO group (45% vs 29%, P = 0.034). Wound complications were seen in 8% (N = 6) of the PICO group and 19% (N = 15) of the non-PICO group (P = 0.042). No significant difference in infection was found between the two groups (3% vs 6%, P = 0.249), but fewer seromas were observed when PICO dressings were used (1.4% vs 7.7%, P = 0.069). Haematoma (2.7% vs 3.8%, P = 0.531) and dehiscence rates (1.4% vs 1.3%, P = 0.735) were similar between the two groups. Routine use of PICO dressings is associated with a reduction in wound complication rates following peripheral vascular surgery, and is cost-effective. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Intravascular volume in cirrhosis. Reassessment using improved methodology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rector, W.G. Jr.; Ibarra, F.

1988-04-01

Previous studies of blood volume (BV) in cirrhosis have either not adjusted BV properly for body size; determined plasma volume from the dilution of labeled albumin 10-20 min postinjection, when some extravascular redistribution has already occurred; and/or not used the correct whole body-peripheral hematocrit ratio (0.82) in calculating whole BV from plasma volume and the peripheral hematocrit. We measured BV with attention to these considerations in 19 patients with cirrhosis and reexamined the determinants of vascular volume and the relationship between vascular volume and sodium retention. BV was calculated as plasma volume (determined from extrapolated plasma activity of intravenously injectedmore » (/sup 131/I)+albumin at time 0) divided by (peripheral hematocrit X 0.82). The result was expressed per kilogram dry body weight, determined by subtracting the mass of ascites (measured by isotope dilution; 1 liter = 1 kg) from the actual body weight of nonedematous patients. Measured and expressed in this way, BV correlated strongly with esophageal variceal size (r = 0.87, P less than 0.05), although not with net portal, right atrial, inferior vena caval, or arterial pressure, and was significantly greater in patients with sodium retention as compared to patients without sodium retention. The principal modifier of vascular volume in cirrhosis is vascular capacity, which is probably mainly determined by the extent of the portasystemic collateral circulation. Increased vascular volume in patients with sodium retention as compared to patients without sodium retention supports the overflow theory of ascites formation.« less

Circulating vascular cell adhesion molecule-1 in pre-eclampsia, gestational hypertension, and normal pregnancy: evidence of selective dysregulation of vascular cell adhesion molecule-1 homeostasis in pre-eclampsia.

PubMed

Higgins, J R; Papayianni, A; Brady, H R; Darling, M R; Walshe, J J

1998-08-01

Our purpose was to investigate circulating levels of vascular cell adhesion molecule-1 in the peripheral and uteroplacental circulations during normotensive and hypertensive pregnancies. This prospective observational study involved 2 patient groups. Group 1 consisted of 22 women with pre-eclampsia and 30 normotensive women followed up longitudinally through pregnancy and post partum. There were an additional 13 women with established gestational hypertension. Group 2 consisted of 20 women with established pre-eclampsia and 19 normotensive control subjects undergoing cesarean delivery. Plasma levels of vascular cell adhesion molecule-1 were measured in blood drawn from the antecubital vein (group 1) and from both the antecubital and uterine veins (group 2). Data were analyzed by analysis of variance. In group 1 vascular cell adhesion molecule-1 levels did not change significantly throughout normal pregnancy and post partum. Women with established pre-eclampsia had increased vascular cell adhesion molecule-1 levels compared with the normotensive pregnancy group (P = .01). Vascular cell adhesion molecule-1 levels were not elevated in women with established gestational hypertension. In group 2 significantly higher levels of vascular cell adhesion molecule-1 were detected in the uteroplacental (P < .0001) and peripheral (P < .0001) circulations of pre-eclamptic women by comparison with normotensive women. In the pre-eclamptic group there was a tendency toward higher vascular cell adhesion molecule-1 levels in the peripheral circulation than in the uteroplacental circulation (P = .06). In contrast to vascular cell adhesion molecule-1, circulating levels of E-selectin and intercellular adhesion molecule-1, other major leukocyte adhesion molecules expressed by the endothelium, were not different in pre-eclamptic and normotensive pregnancies. Established pre-eclampsia is characterized by selective dysregulation of vascular cell adhesion molecule-1 homeostasis. This event is not an early preclinical feature of pre-eclampsia, does not persist post partum, is not a feature of nonproteinuric gestational hypertension, and is not observed with other major leukocyte adhesion molecules. Induction of vascular cell adhesion molecule-1 expression in pre-eclampsia may contribute to leukocyte-mediated tissue injury in this condition or may reflect perturbation of other, previously unrecognized, functions of this molecule in pregnancy.

B-Flow Imaging in Lower Limb Peripheral Arterial Disease and Bypass Graft Ultrasonography.

PubMed

D'Abate, Fabrizio; Ramachandran, Veni; Young, Mark A; Farrah, John; Ahmed, Mudasar H; Jones, Keith; Hinchliffe, Robert J

2016-09-01

Doppler ultrasonography plays a key role in the diagnosis of peripheral arterial disease, but is often limited by pitfalls that may be overcome by B-flow imaging. Thus far, there is little information on B-flow imaging for the assessment of peripheral arterial disease and bypass grafts in lower limbs. This article describes the authors' early experience with B-flow in the lower extremities. Sixty patients were included among a large cohort of patients routinely referred to the vascular laboratory for peripheral arterial disease and bypass graft assessments. Two experienced vascular sonographers performed all scans, comparing color Doppler ultrasonography with B-flow imaging. All scans were performed using a combination of the 9 L linear and C2-9 curvilinear transducers with the LOGIQ E9 system (GE Healthcare, Waukesha, WI, USA). Our experience indicates that this relatively unexplored technology has the potential to significantly improve peripheral blood flow evaluation. Nevertheless, B-flow imaging is not exempt from limitations and should be considered complementary to color Doppler ultrasonography. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Local Tacrolimus (FK506) Delivery for Prevention of Acute Rejection in the Nonhuman Primate Delayed Mixed Chimerism Vascularized Composite Allograft Tolerance Induction Protocol

DTIC Science & Technology

2016-10-01

Chimerism Vascularized Composite Allograft Tolerance Induction Protocol PRINCIPAL INVESTIGATORS: Dr. Curtis L. Cetrulo CONTRACTING ORGANIZATION...Tacrolimus (FK506) Delivery for Prevention of Acute Rejection in the Nonhuman Primate Delayed Mixed Chimerism Vascularized Composite Allograft Tolerance...tacrolimus, FK506, vascularized composite allografts , immune rejection, preclinical, transplant, nonhuman primate model, degradable polymer, tyrosine

Physiological and Therapeutic Vascular Remodeling Mediated by Hypoxia-Inducible Factor 1

NASA Astrophysics Data System (ADS)

Sarkar, Kakali; Semenza, Gregg L.

Angiogenesis along with arteriogenesis and vasculogenesis is a fundamental process in ischemic repair in adult animals including humans. Hypoxia-inducible factor 1 (HIF-1) plays a central role in mediating adaptive responses to hypoxia/ischemia by expressing angiogenic cytokines/growth factors and their cognate receptors. Angiogenic growth factors are the homing signal for circulating angiogenic cells (CACs), which are mobilized to peripheral blood from bone marrow, recruited to target tissues, and promote vascularization. Impairment of HIF-1-mediated gene transcription contributes to the impaired vascular responses in peripheral vascular disease that are associated with aging and diabetes. Promoting neovascularization in ischemic tissues is a promising strategy for the treatment of peripheral vascular disease when surgical or catheter-based revascularization is not possible. Intramuscular injection of an adenovirus encoding a constitutively active form of HIF-1α (AdCA5), into the ischemic limb of diabetic mice increases the recovery of limb perfusion and function, rescues the diabetes-associated impairment of CACs, and increases vascularization. Administration of AdCA5 overcomes the effect of aging on recovery of blood flow in middle-aged mice following femoral artery ligation in a mouse model of age-dependent critical limb ischemia. Intramuscular injection of AdCA5 along with intravenous injection of bone-marrow-derived angiogenic cells cultured in the presence of prolyl-4-hydroxylase inhibitor dimethyloxalylglycine, increases blood flow and limb salvage in old mice following femoral artery ligation. HIF-1α gene therapy increases homing of bone-marrow-derived cells, whereas induction of HIF-1 in these cells increases their retention in the ischemic tissue by increasing their adhesion to endothelium leading to synergistic effects of combined therapy on improving blood flow.

Keratoacanthoma versus invasive squamous cell carcinoma: a comparison of dermatoscopic vascular features in 510 cases.

PubMed

Pyne, John H; Windrum, Graham; Sapkota, Devendra; Wong, Jian Cheng

2014-07-01

Keratoacanthoma (KA) and invasive squamous cell carcinoma (SCC) are keratinocytic tumors displaying vascular features, imaged using dermatoscopy. Compare the dermatoscopy vascular features of KA to SCC. This prospective study examined consecutive cases of 100 KA and 410 invasive SCC in a single private practice in Sydney, Australia. Vascular features were recorded in vivo direct from patients using a non-polarized Delta 20 Heine dermatoscope. These vascular features were: linear, branching, serpentine, hairpin, glomerular and dot vessels, the presence or absence of large diameter tumor vessels, vessel presence in central verses peripheral tumor areas and tumor pink areas in different proportions. Following full excision, all cases were submitted for histopathologic diagnosis. Branching vessels were the only vessel morphology that varied, with a significant incidence in KA (25.0%), compared to SCC (10.7%), P < 0.01. Large vessels were identified in 20.0% of KA, compared to 12.4% in SCC, P = 0.05. No vessels were observed in the central tumor areas in 43.4 % of KA compared to 58.0% of SCC, P = 0.01. Other data comparing the central versus peripheral tumor areas for vessels present did not reveal any distinctive associations. There were no significant differences between KA and SCC when reviewing the selected proportions of pink within the tumor. The vascular features may be confounded by tumor depth in KA. Polarized dermatoscopy may not produce the same findings. This study found branching vessels to have a higher incidence in KA compared to invasive SCC. Although not statistically significant, large diameter vessels were also more frequent in KA. Proportions of pink within the tumor or central verses peripheral tumor vessel distribution were not useful diagnostic features separating KA from SCC using dermatoscopy.

Initial experience with the Cardiva Boomerang vascular closure device in diagnostic catheterization.

PubMed

Doyle, Brendan J; Godfrey, Michael J; Lennon, Ryan J; Ryan, James L; Bresnahan, John F; Rihal, Charanjit S; Ting, Henry H

2007-02-01

The authors studied the safety and efficacy of the Cardiva Boomerang vascular closure device in patients undergoing diagnostic cardiac catheterization. Conventional vascular closure devices (sutures, collagen plugs, or metal clips) have been associated with catastrophic complications including arterial occlusion and foreign body infections; furthermore, they cannot be utilized in patients with peripheral vascular disease or vascular access site in a vessel other than the common femoral artery. The Cardiva Boomerang device facilitates vascular hemostasis without leaving any foreign body behind at the access site, can be used in peripheral vascular disease, and can be used in vessels other than the common femoral artery A total of 96 patients undergoing transfemoral diagnostic cardiac catheterization were included in this study, including 25 (26%) patients with contraindications to conventional closure devices. Femoral angiography was performed prior to deployment of the Cardiva Boomerang closure device. Patients were ambulated at 1 hr after hemostasis was achieved. The device was successfully deployed and hemostasis achieved with the device alone in 95 (99%) patients. The device failed to deploy in 1 (1%) patient and required conversion to standard manual compression. Minor complications were observed in 5 (5%) patients. No patients experienced major complications including femoral hematoma > 4 cm, red blood cell transfusion, retroperitoneal bleed, arteriovenous fistula, pseudoaneurysm, infection, arterial occlusion, or vascular surgery. The Cardiva Boomerang device is safe and effective in patients undergoing diagnostic cardiac catheterization using the transfemoral approach, facilitating early ambulation with low rates of vascular complications. (c) 2006 Wiley-Liss, Inc.

Atherectomy in Peripheral Artery Disease: A Review.

PubMed

Bhat, Tariq M; Afari, Maxwell E; Garcia, Lawrence A

2017-04-01

Peripheral arterial disease (PAD) is a clinical manifestation of systemic atherosclerosis and is associated with significant morbidity and mortality. The physiological force and shear stress from angioplasty and stenting have made PAD treatment challenging. Atherectomy devices have continued to emerge as a major therapy in the management of peripheral vascular disease. This article presents a review of the current literature for the atherectomy devices used in PAD.

Monocyte Chemoattractant Protein-1 in the choroid plexus: a potential link between vascular pro-inflammatory mediators and the CNS during peripheral tissue inflammation

PubMed Central

Mitchell, K.; Yang, H.-Y. T.; Berk, J. D.; Tran, J. H.; Iadarola, M. J.

2009-01-01

During peripheral tissue inflammation, inflammatory processes in the CNS can be initiated by blood-borne pro-inflammatory mediators. The choroid plexus, the site of CSF production, is a highly specialized interface between the vascular system and CNS, and thus, this structure may be an important element in communication between the vascular compartment and the CNS during peripheral tissue inflammation. We investigated the potential participation of the choroid plexus in this process during peripheral tissue inflammation by examining expression of the SCYA2 gene which codes for monocyte chemoattractant protein-1 (MCP-1). MCP-1 protein was previously reported to be induced in a variety of cells during peripheral tissue inflammation. In the basal state, SCYA2 is highly expressed in the choroid plexus as compared to other CNS tissues. During hind paw inflammation, SCYA2 expression was significantly elevated in choroid plexus, whereas it remained unchanged in a variety of brain regions. The SCYA2-expressing cells were strongly associated with the choroid plexus as vascular depletion of blood cells by whole-body saline flush did not significantly alter SCYA2 expression in the choroid plexus. In situ hybridization suggested that the SCYA2-expressing cells were localized to the choroid plexus stroma. To elucidate potential molecular mechanisms of SCYA2 increase, we examined genes in the NF-κβ signaling cascade including TNF-α, IL-1β and IκBα in choroid tissue. Given that we also detected increased levels of MCP-1 protein by ELISA, we sought to identify potential downstream targets of MCP-1 and observed altered expression levels of mRNAs encoding tight junction proteins TJP2 and claudin 5. Finally, we detected a substantial up-regulation of the transcript encoding E-selectin, a molecule which could participate in leukocyte recruitment to the choroid plexus along with MCP-1. Together, these results suggest that profound changes occur in the choroid plexus during peripheral tissue inflammation, likely initiated by blood-borne inflammatory mediators, which may modify events in CNS. PMID:19032979

[The magneto-, photo- and laser therapy of headaches in patients with vascular brain lesions].

PubMed

Troshin, V D; Miasnikov, I G; Belousova, T E

1994-01-01

To manage vascular cephalalgia, a combined approach is proposed: segmentally oriented magnetic, photo- and photomagnetic therapy plus intravenous laser treatment. The effect was directly correlated with cerebral hemodynamic condition, damage to vegetative innervation segmental-peripheral link and physiotherapeutic factors.

Safety of contemporary percutaneous peripheral arterial interventions in the elderly insights from the BMC2 PVI (Blue Cross Blue Shield of Michigan Cardiovascular Consortium Peripheral Vascular Intervention) registry.

PubMed

Plaisance, Benjamin R; Munir, Khan; Share, David A; Mansour, M Ashraf; Fox, James M; Bove, Paul G; Riba, Arthur L; Chetcuti, Stanley J; Gurm, Hitinder S; Grossman, P Michael

2011-06-01

This study sought to evaluate the effect of age on procedure type, periprocedural management, and in-hospital outcomes of patients undergoing lower-extremity (LE) peripheral vascular intervention (PVI). Surgical therapy of peripheral arterial disease is associated with significant morbidity and mortality in the elderly. There are limited data related to the influence of advanced age on the outcome of patients undergoing percutaneous LE PVI. Clinical presentation, comorbidities, and in-hospital outcomes of patients undergoing LE PVI in a multicenter, multidisciplinary registry were compared between 3 age groups: < 70 years, between 70 and 80 years, and ≥ 80 years (elderly group). In our cohort, 7,769 patients underwent LE PVI. The elderly patients were more likely to be female and to have a greater burden of comorbidities. Procedural success was lower in the elderly group (74.2% for age ≥ 80 years vs. 78% for age 70 to < 80 years and 81.4% in patients age < 70 years, respectively; p < 0.0001). Unadjusted rates of procedure-related vascular access complications, post-procedure transfusion, contrast-induced nephropathy, amputation, and major adverse cardiac events were higher in elderly patients. After adjustment for baseline covariates, the elderly patients were more likely to experience vascular access complications; however, advanced age was not found to be associated with major adverse cardiac events, transfusion, contrast-induced nephropathy, or amputation. Contemporary PVI can be performed in elderly patients with high procedural and technical success with low rates of periprocedural complications including mortality. These findings may support the notion of using PVI as a preferred revascularization strategy in the treatment of severe peripheral arterial disease in the elderly population. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Tolerance to Vascularized Composite Allografts in Canine Mixed Hematopoietic Chimeras

PubMed Central

Mathes, David W.; Hwang, Billanna; Graves, Scott S.; Edwards, James; Chang, Jeff; Storer, Barry E.; Butts-Miwongtum, Tiffany; Sale, George E.; Nash, Richard A.; Storb, Rainer.

2012-01-01

Background Mixed donor-host chimerism, established through hematopoietic cell transplantation (HCT), is a highly reproducible strategy for the induction of tolerance towards solid organs. Here, we ask whether a nonmyeloablative conditioning regimen establishing mixed donor-host chimerism leads to tolerance of highly antigenic vascularized composite allografts. Methods Stable mixed chimerism was established in dogs given a sublethal dose (1–2 Gy) total body irradiation before and a short course of immunosuppression after dog leukocyte antigen-identical marrow transplantation. Vascularized composite allografts from marrow donors were performed after a median of 36 (range 4-54) months after HCT. Results All marrow recipients maintained mixed donor-host hematopoietic chimerism and accepted composite tissue grafts for periods ranging between 52 and 90 weeks; in turn, marrow donors rejected vascularized composite allografts from their respective marrow recipients within 18–29 days. Biopsies of muscle and skin of vascularized composite allografts from mixed chimeras showed few infiltrating cells compared to extensive infiltrates in biopsies of vascularized composite allografts from marrow donors. Elevated levels of CD3+ FoxP3+ T-regulatory cells were found in skin and muscle of vascularized composite allografts of mixed chimeras compared to normal tissues. In mixed chimeras, increased numbers of T-regulatory cells were found in draining compared to non-draining lymph nodes of vascularized composite allografts. Conclusion These data suggest that nonmyeloablative HCT may form the basis for future clinical applications of solid organ transplantation and that T-regulatory cells may function towards maintenance of the vascularized composite allograft. PMID:22082819

The role of atherectomy in the treatment of lower extremity peripheral artery disease

PubMed Central

2012-01-01

Background The incidence of lower extremity peripheral artery disease (LE-PAD) continues to increase and associated morbidity remains high. Despite the significant development of percutaneous revascularization strategies, over the past decade, LE-PAD still represents a unique challenge for interventional cardiologists and vascular surgeons. Method Typical features of atherosclerosis that affects peripheral vascular bed (diffuse nature, poor distal runoff, critical limb ischemia, chronic total occlusion) contribute to the disappointing results of traditional percutaneous transluminal angioplasty (PTA). New technologies have been developed in attempt to improve the safety and effectiveness of percutaneous revascularization. Among these, atherectomy, debulking and removing atherosclerotic plaque, offers the potential advantage of eliminating stretch on arterial walls and reducing rates of restenosis. Conclusions This review summarizes the features and the current applications of new debulking devices. PMID:23173800

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cotroneo, Antonio Raffaele; Iezzi, Roberto; Marano, Giuseppe

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,more » 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.« less

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

WNTLESS IS REQUIRED FOR PERIPHERAL LUNG DIFFERENTIATION AND PULMONARY VASCULAR DEVELOPMENT

PubMed Central

Cornett, Bridget; Snowball, John; Varisco, Brian M.; Lang, Richard; Whitsett, Jeffrey; Sinner, Debora

2013-01-01

Wntless (Wls), a gene highly conserved across the animal kingdom, encodes for a transmembrane protein that mediates Wnt ligand secretion. Wls is expressed in developing lung, wherein Wnt signaling is necessary for pulmonary morphogenesis. We hypothesize that Wls plays a critical role in modulating Wnt signaling during lung development and therefore affects processes critical for pulmonary morphogenesis. We generated conditional Wls mutant mice utilizing Shh-Cre and Dermo1-Cre mice to delete Wls in the embryonic respiratory epithelium and mesenchyme, respectively. Epithelial deletion of Wls disrupted lung branching morphogenesis, peripheral lung development and pulmonary endothelial differentiation. Epithelial Wls mutant mice died at birth due to respiratory failure caused by lung hypoplasia and pulmonary hemorrhage. In the lungs of these mice, VEGF and Tie2-angiopoietin signaling pathways, which mediate vascular development, were downregulated from early stages of development. In contrast, deletion of Wls in mesenchymal cells of the developing lung did not alter branching morphogenesis or early mesenchymal differentiation. In vitro assays support the concept that Wls acts in part via Wnt5a to regulate pulmonary vascular development. We conclude that epithelial Wls modulates Wnt ligand activities critical for pulmonary vascular differentiation and peripheral lung morphogenesis. These studies provide a new framework for understanding the molecular mechanisms underlying normal pulmonary vasculature formation and the dysmorphic pulmonary vasculature development associated with congenital lung disease. PMID:23523683

Wntless is required for peripheral lung differentiation and pulmonary vascular development.

PubMed

Cornett, Bridget; Snowball, John; Varisco, Brian M; Lang, Richard; Whitsett, Jeffrey; Sinner, Debora

2013-07-01

Wntless (Wls), a gene highly conserved across the animal kingdom, encodes for a transmembrane protein that mediates Wnt ligand secretion. Wls is expressed in developing lung, wherein Wnt signaling is necessary for pulmonary morphogenesis. We hypothesize that Wls plays a critical role in modulating Wnt signaling during lung development and therefore affects processes critical for pulmonary morphogenesis. We generated conditional Wls mutant mice utilizing Shh-Cre and Dermo1-Cre mice to delete Wls in the embryonic respiratory epithelium and mesenchyme, respectively. Epithelial deletion of Wls disrupted lung branching morphogenesis, peripheral lung development and pulmonary endothelial differentiation. Epithelial Wls mutant mice died at birth due to respiratory failure caused by lung hypoplasia and pulmonary hemorrhage. In the lungs of these mice, VEGF and Tie2-angiopoietin signaling pathways, which mediate vascular development, were downregulated from early stages of development. In contrast, deletion of Wls in mesenchymal cells of the developing lung did not alter branching morphogenesis or early mesenchymal differentiation. In vitro assays support the concept that Wls acts in part via Wnt5a to regulate pulmonary vascular development. We conclude that epithelial Wls modulates Wnt ligand activities critical for pulmonary vascular differentiation and peripheral lung morphogenesis. These studies provide a new framework for understanding the molecular mechanisms underlying normal pulmonary vasculature formation and the dysmorphic pulmonary vasculature development associated with congenital lung disease. Copyright © 2013 Elsevier Inc. All rights reserved.

Cilostazol prevents foot ulcers in diabetic patients with peripheral vascular disease.

PubMed

de Franciscis, Stefano; Gallelli, Luca; Battaglia, Luigi; Molinari, Vincenzo; Montemurro, Rossella; Stillitano, Domenico M; Buffone, Gianluca; Serra, Raffaele

2015-06-01

Diabetic patients are at high risk of foot ulcerations that may lead to limb amputations with important socio-economic impact. Peripheral vascular disease may be frequently associated in diabetes mellitus type II with its main symptom, intermittent claudication. Many studies reported the known efficacy of cilostazol in treating vascular claudication. Metalloproteinase-9 (MMP-9) seems to be a biochemical marker implicated in chronic wounds and in particular in diabetic foot ulcers. Cilostazol appears to have a lowering effect on MMP-9 levels and this may suggest a beneficial effect in order to prevent or retard the onset of foot ulcer in diabetic patients. In our study, two groups of diabetic patients with peripheral vascular disease were divided into two groups according to the presence of claudication in order to receive cilostazol. Group A (31 patients without claudication) were not eligible to receive cilostazol whereas Group B (47 patients with claudication) received cilostazol administration for 24 weeks (100 mg orally twice daily). Median follow up was of 16 months. During the follow up, 4·25% of patients of Group B and 35·48% of patients of Group A (P < 0·01) showed onset of foot ulceration. Although further randomised and controlled studies are required cilostazol seems to show beneficial effects for primary prevention of diabetic foot ulcers. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

[Usefulness of the ankle-arm index for detection of peripheral arterial disease in a working population of Junta de Andalucía at Málaga].

PubMed

Alonso, Inmaculada; Valdivielso, Pedro; Josefa Zamudio, María; Sánchez Chaparro, Miguel Angel; Pérez, Francisca; Ramos, Heliodoro; González Santos, Pedro

2009-01-17

Detection of asymptomatic peripheral arterial disease increases the risk of vascular morbibity and mortality. We aimed to estimate the prevalence of clinical and subclinical peripheral arterial disease using the ankle-arm index (AAI) as diagnostic tool in a working population. We included 450 workers, older than 50 years old, attending voluntary regular health check-up at Centro de Prevención de Riesgos Laborales de la Junta de Andalucía in Málaga (Spain). We recorded clinical and anthopometrical data. Blood samples were taken after an overnight fast. Vascular risk was calculated using Framinghan and SCORE scales. Every participant was asked for symptoms of intermittent claudicatio and AAI was measured. AAI was considered normal within 0.9-1.3 values. Most of our workers were at low- or moderate vascular risk. Only 48 (10.6%) of individuals had an abnormal AAI: 9 (2%) showed an AAI<0.9 and 39 (8.6%) showed an AAI>1.3. An AAI<0.9 was found in 19% of those with a SCORE risk > or = 5%, and in 11% of those having a Framinghan risk > or = 20%. Intermittent claudication was present in 4 out of 9 (44%) of those having an AAI<0.9 and in 7 out of 402 (1.7%) with a normal AAI. Systematic screening of peripheral arterial disease using the AAI is not recommended in active working population over 50 years-old of age. Thus, AAI measurement is indicated only for those individuals suffering from intermitent claudicatio and those who are at moderate- or high vascular risk.

Endurance exercise training increases peripheral vascular response in human fingers.

PubMed

Katayama, K; Shimoda, M; Maeda, J; Takemiya, T

1998-10-01

The purpose of this study was to clarify whether peripheral vascular response to alteration of transmural pressure is changed by endurance exercise training. The healthy male subjects (training group; n = 6) performed endurance exercise training that consisted of cycle ergometer exercise 5 d.week-1 and 30 min.d-1 for a period of 8 weeks. Changes in the peripheral vascular response to alteration of transmural pressure in the human finger were measured by a differential digital photoplethysmogram (DeltaDPG) and blood pressure during passive movement of the arm to different vertical hand positions relative to heart level. Following 8 weeks of endurance training, percent changes in DeltaDPG from heart level in the training group increased significantly (mean +/- SD, -48.1 +/- 7. 3 to -58.7 +/- 9.3% at the lowered position, 46.1 +/- 13.4 to 84.6 +/- 8.8% at the elevated position, p<0.05). Similarly, the arterial compliance index, which was calculated from DeltaDPG-P wave amplitude and arterial pulse pressure, also significantly changed in the training group over the 8 weeks (5.6 +/- 1.3 to 2.7 +/- 1.6 mV. V-1.s-1.mmHg-1 at the lowered position, 30.0 +/- 12.4 to 54.4 +/- 18. 9 mV.V-1.s-1.mmHg-1 at the elevated position ). Maximal oxygen uptake (V.O2 max) was significantly increased in the training group. On the other hand, the control group (n = 6) showed no significant changes in all parameters for 8 weeks. Therefore these results suggest that endurance exercise training induces an increase in peripheral vascular response to alteration of transmural pressure in the human finger.

Relationship between vascular endothelium and periodontal disease in atherosclerotic lesions: Review article

PubMed Central

Saffi, Marco Aurélio Lumertz; Furtado, Mariana Vargas; Polanczyk, Carisi Anne; Montenegro, Márlon Munhoz; Ribeiro, Ingrid Webb Josephson; Kampits, Cassio; Haas, Alex Nogueira; Rösing, Cassiano Kuchenbecker; Rabelo-Silva, Eneida Rejane

2015-01-01

Inflammation and endothelial dysfunction are linked to the pathogenesis of atherosclerotic disease. Recent studies suggest that periodontal infection and the ensuing increase in the levels of inflammatory markers may be associated with myocardial infarction, peripheral vascular disease and cerebrovascular disease. The present article aimed at reviewing contemporary data on the pathophysiology of vascular endothelium and its association with periodontitis in the scenario of cardiovascular disease. PMID:25632316

[Magnetotherapy in obliterating vascular diseases of the lower extremities].

PubMed

Kirillov, Iu B; Shval'b, P G; Lastushkin, A V; Baranov, V M; Sigaev, A A; Zueva, G V; Karpov, E I

1992-01-01

The investigators have developed a polymagnetic system "Avrora-MK-01" employing running impulse magnetic field to treat diseases of the leg vessels by the action on peripheral capillary bed. At a pregangrene stage a positive effect on peripheral capillaries was achieved in 75-82% of the patients treated.

Tolerance in Nonhuman Primates by Delayed Mixed Chimerism

DTIC Science & Technology

2015-10-01

Vascularized composite allografts (VCA) are transplants containing multiple tissue types (including bone, muscle, skin, nerves and blood vessels), which offer...15 11. Appendices…………………………………………………………………………………. 15 4 INTRODUCTION Vascularized composite allografts (VCA) are...can be expected to lead to rapid translation into clinical trials. KEYWORDS Vascularized composite allograft, vascularized composite

Effect of histidine on sorafenib-induced vascular damage: Analysis using novel medaka fish model.

PubMed

Shinagawa-Kobayashi, Yoko; Kamimura, Kenya; Goto, Ryo; Ogawa, Kohei; Inoue, Ryosuke; Yokoo, Takeshi; Sakai, Norihiro; Nagoya, Takuro; Sakamaki, Akira; Abe, Satoshi; Sugitani, Soichi; Yanagi, Masahiko; Fujisawa, Koichi; Nozawa, Yoshizu; Koyama, Naoto; Nishina, Hiroshi; Furutani-Seiki, Makoto; Sakaida, Isao; Terai, Shuji

2018-02-05

Sorafenib (SFN) is an anti-angiogenic chemotherapeutic that prolongs survival of patients with hepatocellular carcinoma (HCC); its side effects, including vascular damages such as hand-foot syndrome (HFS), are a major cause of therapy discontinuation. We previously reported that maintenance of peripheral blood flow by intake of dried bonito broth (DBB) significantly prevented HFS and prolonged the administration period. The amino acids contained in DBB probably contribute to its effects, but the mechanism has not been clarified. We hypothesized that histidine, the largest component among the amino acids contained in DBB, has effects on SFN-induced vascular damage, and evaluated this possibility using a novel medaka fish model. The fli::GFP transgenic medaka fish model has a fluorescently visible systemic vasculature. We fed the fish with SFN with and without histidine to compare blood flow and vascular structure among the differently fed models. The vascular cross-sectional area of each fish was measured to determine vascular diameter changes. Our results demonstrated that SFN-fed medaka developed a narrower vascular diameter. In addition, this narrowing was counteracted by addition of histidine to the medaka diet. We observed no positive effect of histidine on regeneration of cut vessels or on cell growth of endothelial cells and HCC cell lines. We proved the efficacy of the medaka model to assess vascular changes after administration of specific chemicals. And our results suggest that SFN causes vascular damage by narrowing peripheral vessel diameter, and that histidine effectively counteracts these changes to maintain blood flow. Copyright © 2018 Elsevier Inc. All rights reserved.

Branding of vascular surgery.

PubMed

Perler, Bruce A

2008-03-01

The Society for Vascular Surgery surveyed primary care physicians (PCPs) to understand how PCPs make referral decisions for their patients with peripheral vascular disease. Responses were received from 250 PCPs in 44 states. More than 80% of the respondents characterized their experiences with vascular surgeons as positive or very positive. PCPs perceive that vascular surgeons perform "invasive" procedures and refer patients with the most severe vascular disease to vascular surgeons but were more than twice as likely to refer patients to cardiologists, believing they are better able to perform minimally invasive procedures. Nevertheless, PCPs are receptive to the notion of increasing referrals to vascular surgeons. A successful branding campaign will require considerable education of referring physicians about the totality of traditional vascular and endovascular care increasingly provided by the contemporary vascular surgical practice and will be most effective at the local grassroots level.

Novel Applications of Radionuclide Imaging in Peripheral Vascular Disease

PubMed Central

Stacy, Mitchel R.; Sinusas, Albert J.

2015-01-01

Peripheral vascular disease (PVD) is a progressive atherosclerotic disease that leads to stenosis or occlusion of blood vessels supplying the lower extremities. Current diagnostic imaging techniques commonly focus on evaluation of anatomy or blood flow at the macrovascular level and do not permit assessment of the underlying pathophysiology associated with disease progression or treatment response. Molecular imaging with radionuclide-based approaches, such as PET and SPECT, can offer novel insight into PVD by providing non-invasive assessment of biological processes such as angiogenesis and atherosclerosis. This review discusses emerging radionuclide-based imaging approaches that have potential clinical applications in the evaluation of PVD progression and treatment. PMID:26590787

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.

[Study of the infectivity of Candida on peripheral vascular catheters collected from the University Hospital of Tlemcen].

PubMed

Seghir, A; Boucherit-Otmani, Z; Boucherit, K; Sari-Belkharroubi, L

2017-12-01

Yeasts can adhere to medical implants and cause infections responsible for high morbidity and mortality among hospitalized patients. The objective of this study is to investigate the infectivity on peripheral vascular catheters collected from general surgery and cardiology in University Hospital of Tlemcen. The results showed that from 29 samples altered by yeast, 35 Candida sp. strains were isolated. However, Candida albicans is the most isolated species in an infectious context. Risk factors that accompanied the infections are the duration of implantation, male gender, and bacterial presence. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Brain-peripheral cell crosstalk in white matter damage and repair.

PubMed

Hayakawa, Kazuhide; Lo, Eng H

2016-05-01

White matter damage is an important part of cerebrovascular disease and may be a significant contributing factor in vascular mechanisms of cognitive dysfunction and dementia. It is well accepted that white matter homeostasis involves multifactorial interactions between all cells in the axon-glia-vascular unit. But more recently, it has been proposed that beyond cell-cell signaling within the brain per se, dynamic crosstalk between brain and systemic responses such as circulating immune cells and stem/progenitor cells may also be important. In this review, we explore the hypothesis that peripheral cells contribute to damage and repair after white matter damage. Depending on timing, phenotype and context, monocyte/macrophage can possess both detrimental and beneficial effects on oligodendrogenesis and white matter remodeling. Endothelial progenitor cells (EPCs) can be activated after CNS injury and the response may also influence white matter repair process. These emerging findings support the hypothesis that peripheral-derived cells can be both detrimental or beneficial in white matter pathology in cerebrovascular disease. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia, edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock. Copyright © 2015 Elsevier B.V. All rights reserved.

Assessment of risk of peripheral vascular disease and vascular care capacity in low- and middle-income countries.

PubMed

Gyedu, A; Stewart, B T; Nakua, E; Quansah, R; Donkor, P; Mock, C; Hardy, M; Yangni-Angate, K H

2016-01-01

This study aimed to describe national peripheral vascular disease (PVD) risk and health burden, and vascular care capacity in Ghana. The gap between PVD burden and vascular care capacity in low- and middle-income countries was defined, and capacity improvement priorities were identified. Data to estimate PVD risk factor burden were obtained from the World Health Organization Study on Global Ageing and Adult Health (SAGE), Ghana, and the Institute of Health Metrics and Evaluation Global Burden of Disease (IHME GBD) database. In addition, a novel nationwide assessment of vascular care capacity was performed, with 20 vascular care items assessed at 40 hospitals in Ghana. Factors contributing to specific item deficiency were described. From the SAGE database, there were 4305 respondents aged at least 50 years with data to estimate PVD risk. Of these, 57·4 per cent were at moderate to risk high of PVD with at least three risk factors; extrapolating nationally, the estimate was 1 654 557 people. Based on IHME GBD data, the estimated disability-adjusted life-years incurred from PVD increased fivefold from 1990 to 2010 (from 6·3 to 31·7 per 100 000 persons respectively). Vascular care capacity assessment demonstrated marked deficiencies in items for diagnosis, and in perioperative and vascular surgical care. Deficiencies were most often due to absence of equipment, lack of training and technology breakage. Risk factor reduction and management as well as optimization of current resources are paramount to avoid the large burden of PVD falling on healthcare systems in low- and middle-income countries. These countries are not well equipped to handle vascular surgical care, and rapid development of such capacity would be difficult and expensive. © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

Positioning Vascularized Composite Allotransplantation within the Spectrum of Transplantation

DTIC Science & Technology

2015-10-01

1 AWARD NUMBER: W81XWH-13-2-0057 TITLE: Positioning Vascularized Composite Allotransplantation within the Spectrum of Transplantation...Positioning Vascularized Composite Allotransplantation within the Spectrum of Transplantation 5b. GRANT NUMBER W81XWH-13-2-0057 5c. PROGRAM ELEMENT...Finally in Aim 8 we will develop standardization of protocols and clinical monitoring and treatment for VCA targeting vascular health. hand and face

Using the Vessel Health and Preservation framework to enhance vein assessment and vascular access device selection.

PubMed

Shaw, Sally Jane

2017-07-12

There is a range of risk factors that can lead to peripheral intravenous (IV) cannula failure, and several failed cannulation attempts can result in the patient experiencing increased pain, discomfort and delays in receiving IV therapy. The Vessel Health and Preservation (VHP) framework is a tool that can be used to improve clinical decision-making and the patient experience in relation to vascular access and IV therapy. Use of the VHP framework can ensure the right vein and right vascular access device (VAD) is selected at the right time for each patient. This article describes how healthcare practitioners can use the VHP framework to support and enhance vein assessment and VAD selection. It outlines the various types of VAD available, focusing on short-term peripheral IV cannulae, which are the most commonly used devices. It also explores the potential benefits of implementing the VHP framework in clinical areas.

Dynamic denitrosylation via S-nitrosoglutathione reductase regulates cardiovascular function

PubMed Central

Beigi, Farideh; Gonzalez, Daniel R.; Minhas, Khalid M.; Sun, Qi-An; Foster, Matthew W.; Khan, Shakil A.; Treuer, Adriana V.; Dulce, Raul A.; Harrison, Robert W.; Saraiva, Roberto M.; Premer, Courtney; Schulman, Ivonne Hernandez; Stamler, Jonathan S.; Hare, Joshua M.

2012-01-01

Although protein S-nitrosylation is increasingly recognized as mediating nitric oxide (NO) signaling, roles for protein denitrosylation in physiology remain unknown. Here, we show that S-nitrosoglutathione reductase (GSNOR), an enzyme that governs levels of S-nitrosylation by promoting protein denitrosylation, regulates both peripheral vascular tone and β-adrenergic agonist-stimulated cardiac contractility, previously ascribed exclusively to NO/cGMP. GSNOR-deficient mice exhibited reduced peripheral vascular tone and depressed β-adrenergic inotropic responses that were associated with impaired β-agonist–induced denitrosylation of cardiac ryanodine receptor 2 (RyR2), resulting in calcium leak. These results indicate that systemic hemodynamic responses (vascular tone and cardiac contractility), both under basal conditions and after adrenergic activation, are regulated through concerted actions of NO synthase/GSNOR and that aberrant denitrosylation impairs cardiovascular function. Our findings support the notion that dynamic S-nitrosylation/denitrosylation reactions are essential in cardiovascular regulation. PMID:22366318

Vascular Disease and Kidney Stones: Abdominal Aortic Calcifications Are Associated with Low Urine pH and Hypocitraturia.

PubMed

Patel, Nishant D; Ward, Ryan D; Calle, Juan; Remer, Erick M; Monga, Manoj

2017-09-01

Vascular calcifications are associated with nephrolithiasis. Although studies have demonstrated correlations with vascular disease and calcium stones in kidney stone formers (KSF), an etiologic link has remained elusive. As a noncontrast CT (NCCT) scan is typically part of a stone evaluation, our objective was to evaluate the association of NCCT-based assessment of abdominal aortic calcifications (AACs) with 24-hour urine parameters and stone composition. Ninety-seven KSF were included with CT imaging and 24-hour urine studies. For each patient, semi-automated CT software was utilized to provide an AAC Agatston score from the celiac axis to the aortic bifurcation. Univariate analysis was performed to compare patients with or without AAC. Multivariate logistic regression was performed to assess for variables associated with 24-hour urine parameters and stone composition. The presence of AAC was associated with hypertension, diabetes, peripheral vascular disease, and coronary artery disease. Patients with any AAC showed lower 24-hour urine citrate (399 vs 593 mg/day, p < 0.001) and lower 24-hour urine pH (5.862 vs 6.328, p = 0.003). When controlling for age, system comorbidities, the presence of AAC was associated with low urine pH <6 (odds ratio [OR] 2.86, p = 0.032) and hypocitraturia <320 mg/day (OR 4.37, p = 0.005). The receiver operating characteristic curve showed that increasing AAC was associated with low urine pH (area under the curve [AUC] 0.683, p = 0.002) and uric acid stone formation (AUC 0.698, p = 0.045). NCCT-based diagnosis of AAC is associated with low urine pH, hypocitraturia, and uric acid stone formation. The presence of AAC could be considered an additional prognosticator for the utility of alkalinization therapy.

Printable Biodegradable Hydrogel for Skin Wound Dressing Using Inkjet Printing Technology

ERIC Educational Resources Information Center

Yanez, Maria

2013-01-01

Chronic wounds are becoming more frequent. Foot ulcers affect approximately 10%-15% of patients with diabetes throughout their lifetimes, and by 2025, it is estimated the prevalence of diabetes will be 250 million people in the worldwide. There is increased potential for patients with peripheral neuropathy and peripheral vascular disease to suffer…

Peripheral nerve injuries secondary to missiles.

PubMed

Katzman, B M; Bozentka, D J

1999-05-01

Peripheral nerve injuries secondary to missiles can present some of the most challenging problems faced by hand surgeons. This article reviews the pertinent neural anatomy, injury classifications, and repair techniques. Options in the management of nerve gaps are presented including the use of vascularized nerve grafts. The results are discussed and a treatment algorithm is presented.

Peripheral Neuropathy and Nerve Compression Syndromes in Burns.

PubMed

Strong, Amy L; Agarwal, Shailesh; Cederna, Paul S; Levi, Benjamin

2017-10-01

Peripheral neuropathy and nerve compression syndromes lead to substantial morbidity following burn injury. Patients present with pain, paresthesias, or weakness along a specific nerve distribution or experience generalized peripheral neuropathy. The symptoms manifest at various times from within one week of hospitalization to many months after wound closure. Peripheral neuropathy may be caused by vascular occlusion of vasa nervorum, inflammation, neurotoxin production leading to apoptosis, and direct destruction of nerves from the burn injury. This article discusses the natural history, diagnosis, current treatments, and future directions for potential interventions for peripheral neuropathy and nerve compression syndromes related to burn injury. Copyright © 2017 Elsevier Inc. All rights reserved.

Protease-Activated Receptor 2 Activation Inhibits N-Type Ca2+ Currents in Rat Peripheral Sympathetic Neurons

PubMed Central

Kim, Young-Hwan; Ahn, Duck-Sun; Kim, Myeong Ok; Joeng, Ji-Hyun; Chung, Seungsoo

2014-01-01

The protease-activated receptor (PAR)-2 is highly expressed in endothelial cells and vascular smooth muscle cells. It plays a crucial role in regulating blood pressure via the modulation of peripheral vascular tone. Although several mechanisms have been suggested to explain PAR-2-induced hypotension, the precise mechanism remains to be elucidated. To investigate this possibility, we investigated the effects of PAR-2 activation on N-type Ca2+ currents (ICa-N) in isolated neurons of the celiac ganglion (CG), which is involved in the sympathetic regulation of mesenteric artery vascular tone. PAR-2 agonists irreversibly diminished voltage-gated Ca2+ currents (ICa), measured using the patch-clamp method, in rat CG neurons, whereas thrombin had little effect on ICa. This PAR-2-induced inhibition was almost completely prevented by ω-CgTx, a potent N-type Ca2+ channel blocker, suggesting the involvement of N-type Ca2+ channels in PAR-2-induced inhibition. In addition, PAR-2 agonists inhibited ICa–N in a voltage-independent manner in rat CG neurons. Moreover, PAR-2 agonists reduced action potential (AP) firing frequency as measured using the current-clamp method in rat CG neurons. This inhibition of AP firing induced by PAR-2 agonists was almost completely prevented by ω-CgTx, indicating that PAR-2 activation may regulate the membrane excitability of peripheral sympathetic neurons through modulation of N-type Ca2+ channels. In conclusion, the present findings demonstrate that the activation of PAR-2 suppresses peripheral sympathetic outflow by modulating N-type Ca2+ channel activity, which appears to be involved in PAR-2-induced hypotension, in peripheral sympathetic nerve terminals. PMID:25410909

An interesting case of peripheral vascular disease, vascular reperfusion, and subsequent development of pain due to Paget's disease of bone.

PubMed

Kwun, Sunna; Tucci, Joseph R

2013-01-01

To present a case of Paget's disease of bone that was unmasked after vascular reperfusion. In this case study, we review the presentation, evaluation, diagnosis, and management of a patient with Paget's disease and peripheral vascular disease. A 79-year-old-woman with a history of coronary artery heart disease and recent finding of a T5 compression fracture was hospitalized for evaluation of right lower extremity claudication. Angiography demonstrated a focal complete occlusion of the distal right femoral and popliteal arteries. A self-expanding stent was placed in the distal femoral and popliteal arteries. Approximately 48 hours after the procedure, the patient developed severe, right lower leg pain. On endocrine evaluation, the patient was found to have clinical signs suggesting Paget's disease of bone, which was subsequently confirmed by imaging. This patient's development of severe pain following reperfusion of distal femoral and popliteal arteries is in keeping with the known and aforementioned hypervascularity of pagetic bone. The finding of increased warmth over an area of skeletal deformation should always raise the possibility of Paget's disease of bone.

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

PubMed

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

2007-10-01

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

Use of a latest-generation vascular plug for peripheral vascular embolization with use of a diagnostic catheter: preliminary clinical experience.

PubMed

Mordasini, Pasquale; Szucs-Farkas, Zsolt; Do, Do-Dai; Gralla, Jan; Kettenbach, Joachim; Hoppe, Hanno

2010-08-01

The latest-generation Amplatzer vascular plug (AVP), the AVP 4, is designed for embolization of smaller vessels without a sheath or guiding catheter. This study evaluated the AVP 4 in peripheral vascular embolization. Embolization with the AVP 4 was attempted in 13 patients (11 men) for trauma (n = 7) and other indications (n = 6). Technical success rate, vascular bed, size of catheter, and number and size of AVP 4 devices were recorded. Embolization with the AVP 4 was successful in 10 of 13 patients (77%). In trauma patients (n = 7), embolization of the splenic artery (n = 4), lumbar artery (n = 2), and superior gluteal artery (n = 1) was performed. In other patients, preoperative embolization of the right portal vein (n = 1), a gastric varix after transjugular intrahepatic portosystemic shunt creation (n = 1), an aneurysm of the internal iliac artery (n = 1), and inferior mesenteric artery (IMA) embolization before aneurysm repair (n = 2) was performed. Sizes of the AVP 4 were 4 mm (n = 6), 6 mm (n = 5), and 8 mm (n = 1). In all patients, 4- and 5-F catheters with a 0.038-inch minimum inner lumen were used. In one patient, IMA embolization was attempted via a femoral approach but was unsuccessful as a result of repeated catheter tip dislocation because of acute angle; coils were used instead. Peripheral embolization with the AVP 4 was successful in the majority of patients. Future comparative study is necessary to evaluate this device's benefits over other embolization materials such as earlier-generation AVPs or microcoils. Copyright (c) 2010 SIR. Published by Elsevier Inc. All rights reserved.

Overlapping Mechanisms of Peripheral Nerve Regeneration and Angiogenesis Following Sciatic Nerve Transection

PubMed Central

Wang, Hongkui; Zhu, Hui; Guo, Qi; Qian, Tianmei; Zhang, Ping; Li, Shiying; Xue, Chengbin; Gu, Xiaosong

2017-01-01

Peripheral nervous system owns the ability of self-regeneration, mainly in its regenerative microenvironment including vascular network reconstruction. More recently, more attentions have been given to the close relationship between tissue regeneration and angiogenesis. To explore the overlap of molecular mechanisms and key regulation molecules between peripheral nerve regeneration and angiogenesis post peripheral nerve injury, integrative and bioinformatic analysis was carried out for microarray data of proximal stumps after sciatic nerve transection in SD rats. Nerve regeneration and angiogenesis were activated at 1 day immediately after sciatic nerve transection simultaneously. The more obvious changes of transcription regulators and canonical pathways suggested a phase transition between 1 and 4 days of both nerve regeneration and angiogenesis after sciatic nerve transection. Furthermore, 16 differentially expressed genes participated in significant biological processes of both nerve regeneration and angiogenesis, a few of which were validated by qPCR and immunofluorescent staining. It was demonstrated that STAT3, EPHB3, and Cdc42 co-expressed in Schwann cells and vascular endothelial cells to play a key role in regulation of nerve regeneration and angiogenesis simultaneously response to sciatic nerve transection. We provide a framework for understanding biological processes and precise molecular correlations between peripheral nerve regeneration and angiogenesis after peripheral nerve transection. Our work serves as an experimental basis and a valuable resource to further understand molecular mechanisms that define nerve injury-induced micro-environmental variation for achieving desired peripheral nerve regeneration. PMID:29085283

Overlapping Mechanisms of Peripheral Nerve Regeneration and Angiogenesis Following Sciatic Nerve Transection.

PubMed

Wang, Hongkui; Zhu, Hui; Guo, Qi; Qian, Tianmei; Zhang, Ping; Li, Shiying; Xue, Chengbin; Gu, Xiaosong

2017-01-01

Peripheral nervous system owns the ability of self-regeneration, mainly in its regenerative microenvironment including vascular network reconstruction. More recently, more attentions have been given to the close relationship between tissue regeneration and angiogenesis. To explore the overlap of molecular mechanisms and key regulation molecules between peripheral nerve regeneration and angiogenesis post peripheral nerve injury, integrative and bioinformatic analysis was carried out for microarray data of proximal stumps after sciatic nerve transection in SD rats. Nerve regeneration and angiogenesis were activated at 1 day immediately after sciatic nerve transection simultaneously. The more obvious changes of transcription regulators and canonical pathways suggested a phase transition between 1 and 4 days of both nerve regeneration and angiogenesis after sciatic nerve transection. Furthermore, 16 differentially expressed genes participated in significant biological processes of both nerve regeneration and angiogenesis, a few of which were validated by qPCR and immunofluorescent staining. It was demonstrated that STAT3, EPHB3, and Cdc42 co-expressed in Schwann cells and vascular endothelial cells to play a key role in regulation of nerve regeneration and angiogenesis simultaneously response to sciatic nerve transection. We provide a framework for understanding biological processes and precise molecular correlations between peripheral nerve regeneration and angiogenesis after peripheral nerve transection. Our work serves as an experimental basis and a valuable resource to further understand molecular mechanisms that define nerve injury-induced micro-environmental variation for achieving desired peripheral nerve regeneration.

Imaging findings of intravascular papillary endothelial hyperplasia presenting in extremities: correlation with pathological findings.

PubMed

Lee, Sun Joo; Choo, Hye Jung; Park, Ji Sung; Park, Yeong-Mi; Eun, Choong Ki; Hong, Sung Hwan; Hwang, Ji Young; Lee, In Sook; Lee, Jongmin; Jung, Soo-Jin

2010-08-01

To describe magnetic resonance imaging (MRI) and ultrasound (US) findings of intravascular papillary endothelial hyperplasia (IPEH) arising in extremities. Six patients with IPEH confirmed by surgical resection were reviewed retrospectively. Before resection, 3 patients underwent both MRI and US and 3 patients underwent only MRI. Two radiologists retrospectively reviewed MR/US imaging results and correlated them with pathological features. The 6 IPEHs were diagnosed as 4 mixed forms and 2 pure forms. The pre-existing pathology of four mixed forms was intramuscular or intermuscular hemangioma. By MRI, the mixed form of IPEH (n = 4) revealed iso- to slightly high signal intensity containing nodule-like foci of high signal intensity on T1-weighted images (T1WI) and high signal intensity-containing nodule-like foci of low signal intensity on T2-weighted images (T2WI). The pure form of IPEH (n = 2) showed homogeneous iso- signal intensity on T1WI and high and low signal intensity containing nodule-like foci of low signal intensity on T2WI. On gadolinium-enhanced fat-suppressed T1WI, 50% of cases (n = 3: mixed forms) revealed peripheral, septal, and central enhancement. The other IPEHs (n = 3: 1 mixed and 2 pure forms) showed peripheral and septal enhancement or only peripheral enhancement. By US, two mixed forms of IPEH showed well-defined hypoechoic masses containing hyperechoic septa and central portion with vascularities. One pure form of IPEH was a homogeneous hypoechoic mass with septal and peripheral vascularities on color Doppler imaging. The foci of high signal intensity on T1WI, foci of low signal intensity on T2WI, and non-enhancing portions on MRI and the hypoechoic portion on US were histopathologically correlated with thrombi and the peripheral/septal or central enhancing areas on MRI, hyperechoic septa and the central portion on US, and septal/central or peripheral vascularities on color Doppler imaging corresponded to hypertrophic papillary epithelium and a fibrovascular core. Even though imaging findings of the pure form of IPEH are rather nonspecific, the mixed form of IPEH should be considered a possible diagnosis when a well-defined mass with T2 hyperintense signal containing nodule-like foci of low signal intensity, T1 iso- to slightly hyperintense signal containing nodule-like foci of high signal intensity, and peripheral/septal or central enhancement on MRI is seen in extremities, along with the US finding of a hypoechoic mass containing hyperechoic septa with vascularities.

Dynamic contrast-enhanced magnetic resonance imaging: fundamentals and application to the evaluation of the peripheral perfusion

PubMed Central

Gordon, Yaron; Partovi, Sasan; Müller-Eschner, Matthias; Amarteifio, Erick; Bäuerle, Tobias; Weber, Marc-André; Kauczor, Hans-Ulrich

2014-01-01

Introduction The ability to ascertain information pertaining to peripheral perfusion through the analysis of tissues’ temporal reaction to the inflow of contrast agent (CA) was first recognized in the early 1990’s. Similar to other functional magnetic resonance imaging (MRI) techniques such as arterial spin labeling (ASL) and blood oxygen level-dependent (BOLD) MRI, dynamic contrast-enhanced MRI (DCE-MRI) was at first restricted to studies of the brain. Over the last two decades the spectrum of ailments, which have been studied with DCE-MRI, has been extensively broadened and has come to include pathologies of the heart notably infarction, stroke and further cerebral afflictions, a wide range of neoplasms with an emphasis on antiangiogenic treatment and early detection, as well as investigations of the peripheral vascular and musculoskeletal systems. Applications to peripheral perfusion DCE-MRI possesses an unparalleled capacity to quantitatively measure not only perfusion but also other diverse microvascular parameters such as vessel permeability and fluid volume fractions. More over the method is capable of not only assessing blood flowing through an organ, but in contrast to other noninvasive methods, the actual tissue perfusion. These unique features have recently found growing application in the study of the peripheral vascular system and most notably in the diagnosis and treatment of peripheral arterial occlusive disease (PAOD). Review outline The first part of this review will elucidate the fundamentals of data acquisition and interpretation of DCE-MRI, two areas that often remain baffling to the clinical and investigating physician because of their complexity. The second part will discuss developments and exciting perspectives of DCE-MRI regarding the assessment of perfusion in the extremities. Emerging clinical applications of DCE-MRI will be reviewed with a special focus on investigation of physiology and pathophysiology of the microvascular and vascular systems of the extremities. PMID:24834412

Multicenter Analysis of Immune Biomarkers and Heart Transplant Outcomes: Results of the Clinical Trials in Organ Transplantation-05 Study.

PubMed

Starling, R C; Stehlik, J; Baran, D A; Armstrong, B; Stone, J R; Ikle, D; Morrison, Y; Bridges, N D; Putheti, P; Strom, T B; Bhasin, M; Guleria, I; Chandraker, A; Sayegh, M; Daly, K P; Briscoe, D M; Heeger, P S

2016-01-01

Identification of biomarkers that assess posttransplant risk is needed to improve long-term outcomes following heart transplantation. The Clinical Trials in Organ Transplantation (CTOT)-05 protocol was an observational, multicenter, cohort study of 200 heart transplant recipients followed for the first posttransplant year. The primary endpoint was a composite of death, graft loss/retransplantation, biopsy-proven acute rejection (BPAR), and cardiac allograft vasculopathy (CAV) as defined by intravascular ultrasound (IVUS). We serially measured anti-HLA- and auto-antibodies, angiogenic proteins, peripheral blood allo-reactivity, and peripheral blood gene expression patterns. We correlated assay results and clinical characteristics with the composite endpoint and its components. The composite endpoint was associated with older donor allografts (p < 0.03) and with recipient anti-HLA antibody (p < 0.04). Recipient CMV-negativity (regardless of donor status) was associated with BPAR (p < 0.001), and increases in plasma vascular endothelial growth factor-C (OR 20; 95%CI:1.9-218) combined with decreases in endothelin-1 (OR 0.14; 95%CI:0.02-0.97) associated with CAV. The remaining biomarkers showed no relationships with the study endpoints. While suboptimal endpoint definitions and lower than anticipated event rates were identified as potential study limitations, the results of this multicenter study do not yet support routine use of the selected assays as noninvasive approaches to detect BPAR and/or CAV following heart transplantation. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

Pharmacologic and Nonpharmacologic Approaches to the Treatment of Hypertension with Implications for the Clinical Nurse Specialist

DTIC Science & Technology

1988-01-01

Hypertension 6 14 that assist in regulation of smooth muscle contraction . This results in a lowered peripheral vascular resistance and 6 thus, a lowering of...the effect of epinephrine and also allows the sustained vascular smooth - muscle contraction caused by the catecholamines; this too, contributing to an...hypertension. These agents cause arteriolar dilatation by acting directly on vascular smooth muscle . They do this by interfering with the calcium gates

Effect of reconstructive vascular surgery on red cell deformability--preliminary results.

PubMed Central

Irwin, S T; Rocks, M J; McGuigan, J A; Patterson, C C; Morris, T C; O'Reilly, M J

1983-01-01

Using a simple filtration method, red cell deformability was measured in healthy control subjects and in patients with peripheral vascular disease. Impaired red cell deformability was demonstrated in patients with rest pain or gangrene and in patients with intermittent claudication. An improvement in red cell deformability was demonstrated after successful reconstructive vascular surgery in both patient groups. An improvement in red cell deformability was demonstrated in patients undergoing major limb amputation. PMID:6619311

Visualization of peripheral vasodilative indices in human skin by use of red, green, blue images

NASA Astrophysics Data System (ADS)

Nishidate, Izumi; Tanaka, Noriyuki; Kawase, Tatsuya; Maeda, Takaaki; Yuasa, Tomonori; Aizu, Yoshihisa; Yuasa, Tetsuya; Niizeki, Kyuichi

2013-06-01

We propose a method to visualize the arterial inflow, the vascular resistance, and the venous capacitance in the skin tissue from red, green, blue (RGB) digital color images. The arterial inflow and the venous capacitance in the skin tissue are visualized based on an increase in the rate of change in the total blood concentration and the change of the total blood concentration during upper limb occlusion at a pressure of 50 mmHg. The resultant arterial inflow with the measured mean arterial pressure also provides an image of the vascular resistance in human skin. The arterial inflow, the vascular resistance, and the venous capacitance acquired by the method are well correlated with those obtained from the conventional strain-gauge plethysmograph. The correlation coefficients R between the estimated values by the method and the measurements by the SPG are calculated to be 0.83 (P<0.001) for the arterial inflow, 0.77 (P<0.01) for the vascular resistance, and 0.77 (P<0.01) for the venous capacitance. The arterial inflow and the venous capacitance in the skin tissue are significantly higher in active subjects compared with the sedentary subjects, whereas the vascular resistance was significantly lower in the active subjects compared with the sedentary subjects. The results of the present study indicate the possibility of using the proposed method for evaluating the peripheral vascular functions in human skin.

Red cell 2, 3-diphosphoglycerate levels among diabetic patents with and without vascular complications.

PubMed

Kanter, Y; Bessman, S P; Bessman, A

1975-08-01

There have been differences of opinion among authors concening in the levels of red cell 2,3-diphosphoglycerate (2,3-DPG) and nucleotides in nonacidotic diabetic patients. Our data suggest that abnormal levels of 2, 3-DPG in diabetic patients are related to the presence of vascular complications and not to the duration of the disease per sec. 2,3-DPG levels are normal in diabetic patients with no evidence of vascular complications (group A). In ambulatory patients with vascular complications (group B), significantly higher levels of 2,3-DPG are found than in normal subjects and patients in group A. In hospitalized diabetic patients with active peripheral vascular complications (group C), levels of 2,3-DPG are likewise significantly increased over those of normal subjects and patients of group A. 2,3-DPG was found to be significantly elevated in patients of group C as compared with group B. 2,3-DPG levels in venous blood from infected legs as compared with those of the peripheral venous blood were not significantly different, thereby ruling out local factors. There were no differences in the blood lactate levels in any of the group studied. The elevation of the 2,3-DPG levels may be a reflection of attempted red blood cell compensation for tissue hypoxia in the diabetic with vascular disease.

Pattern of Bone Generation after Irradiation in Vascularized Tissue Engineered Constructs.

PubMed

Eweida, Ahmad; Fathi, Ibrahim; Eltawila, Ahmed M; Elsherif, Ahmad M; Elkerm, Yasser; Harhaus, Leila; Kneser, Ulrich; Sakr, Mahmoud F

2018-02-01

 Regenerative medicine modalities provide promising alternatives to conventional reconstruction techniques but are still deficient after malignant tumor excision or irradiation due to defective vascularization.  We investigated the pattern of bone formation in axially vascularized tissue engineering constructs (AVTECs) after irradiation in a study that mimics the clinical scenario after head and neck cancer. Heterotopic bone generation was induced in a subcutaneously implanted AVTEC in the thigh of six male New Zealand rabbits. The tissue construct was made up of Nanobone (Artoss GmbH; Rostock, Germany) granules mixed with autogenous bone marrow and 80 μL of bone morphogenic protein-2 at a concentration of 1.5 μg/μL. An arteriovenous loop was created microsurgically between the saphenous vessels and implanted in the core of the construct to induce axial vascularization. The constructs were subjected to external beam irradiation on postoperative day 20 with a single dose of 15 Gy. The constructs were removed 20 days after irradiation and subjected to histological and immunohistochemical analysis for vascularization, bone formation, apoptosis, and cellular proliferation.  The vascularized constructs showed homogenous vascularization and bone formation both in their central and peripheral regions. Although vascularity, proliferation, and apoptosis were similar between central and peripheral regions of the constructs, significantly more bone was formed in the central regions of the constructs.  The study shows for the first time the pattern of bone formation in AVTECs after irradiation using doses comparable to those applied after head and neck cancer. Axial vascularization probably enhances the osteoinductive properties in the central regions of AVTECs after irradiation. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Echocardiography in the flight program

NASA Technical Reports Server (NTRS)

Charles, John B.; Bungo, Michael W.; Mulvagh, Sharon L.

1991-01-01

Observations on American and Soviet astronauts have documented the association of changes in cardiovascular function during orthostasis with space flight. A basic understanding of the cardiovascular changes occurring in astronauts requires the determination of cardiac output and total peripheral vascular resistance as a minimum. In 1982, we selected ultrasound echocardiography as our means of acquiring this information. Ultrasound offers a quick, non-invasive and accurate means of determining stroke volume which, when combined with the blood pressure and heart rate measurements of the stand test, allows calculation of changes in peripheral vascular resistance, the body's major response to orthostatic stress. The history of echocardiography in the Space Shuttle Program is discussed and the results are briefly presented.

Exercise considerations in coronary artery disease, peripheral vascular disease, and diabetes mellitus.

PubMed

Armen, Joseph; Smith, Bryan W

2003-01-01

Physical inactivity is a risk factor for cardiovascular disease. Regular aerobic and resistance training increases exercise capacity and plays a role both in the primary and secondary prevention of cardiovascular disease. Patients with coronary artery disease, peripheral vascular disease, or diabetes mellitus must be considered individually when prescribing exercise because their clinical status can vary greatly. In addition, a majority of these patients have multiple comorbid disorders such as renal, neurologic, and retinal disease that may affect their ability to exercise safely. Therefore, a preparticipation medical evaluation is required. An exercise prescription should be tailored to each person's unique set of circumstances and reflect an effort to maximize the anticipated benefits while minimizing the risks.

Familial exudative vitreoretinopathy mimicking persistent hyperplastic primary vitreous.

PubMed

Chang-Godinich, A; Paysse, E A; Coats, D K; Holz, E R

1999-04-01

To report an unusual case of familial exudative vitreoretinopathy in an infant. Case report. A 6-day-old girl had unilateral microphthalmia in the right eye, with a retrolental plaque initially diagnosed as persistent hyperplastic primary vitreous. Three months later, peripheral retinal vascular changes and a fibrovascular ridge were noted in the left eye, suggesting familial exudative vitreoretinopathy as the cause in both eyes. The microphthalmic right eye was unsalvageable. The left eye developed an exudative retinal detachment despite photocoagulation of the peripheral avascular retina. Additional cryotherapy resulted in resolution of the detachment and regression of the vascular changes. With highly asymmetric involvement, neonatal familial exudative vitreoretinopathy can mimic persistent hyperplastic primary vitreous. Fellow eye involvement can progress rapidly.

Cell Based Therapeutic Approach in Vascular Surgery: Application and Review

PubMed Central

Rocca, Aldo; Tafuri, Domenico; Paccone, Marianna; Giuliani, Antonio; Zamboli, Anna Ginevra Immacolata; Surfaro, Giuseppe; Paccone, Andrea; Compagna, Rita; Amato, Maurizo; Serra, Raffaele; Amato, Bruno

2017-01-01

Abstract Multipotent stem cells - such as mesenchymal stem/stromal cells and stem cells derived from different sources like vascular wall are intensely studied to try to rapidly translate their discovered features from bench to bedside. Vascular wall resident stem cells recruitment, differentiation, survival, proliferation, growth factor production, and signaling pathways transduced were analyzed. We studied biological properties of vascular resident stem cells and explored the relationship from several factors as Matrix Metalloproteinases (MMPs) and regulations of biological, translational and clinical features of these cells. In this review we described a translational and clinical approach to Adult Vascular Wall Resident Multipotent Vascular Stem Cells (VW-SCs) and reported their involvement in alternative clinical approach as cells based therapy in vascular disease like arterial aneurysms or peripheral arterial obstructive disease. PMID:29071303

Single passive leg movement-induced hyperemia: a simple vascular function assessment without a chronotropic response.

PubMed

Venturelli, Massimo; Layec, Gwenael; Trinity, Joel; Hart, Corey R; Broxterman, Ryan M; Richardson, Russell S

2017-01-01

Passive leg movement (PLM)-induced hyperemia is a novel approach to assess vascular function, with a potential clinical role. However, in some instances, the varying chronotropic response induced by PLM has been proposed to be a potentially confounding factor. Therefore, we simplified and modified the PLM model to require just a single PLM (sPLM), an approach that may evoke a peripheral hemodynamic response, allowing a vascular function assessment, but at the same time minimizing central responses. To both characterize and assess the utility of sPLM, in 12 healthy subjects, we measured heart rate (HR), stroke volume, cardiac output (CO), mean arterial pressure (MAP), leg blood flow (LBF), and calculated leg vascular conductance (LVC) during both standard PLM, consisting of passive knee flexion and extension performed at 1 Hz for 60 s, and sPLM, consisting of only a single passive knee flexion and extension over 1 s. During PLM, MAP transiently decreased (5 ± 1 mmHg), whereas both HR and CO increased from baseline (6.0 ± 1.1 beats/min, and 0.8 ± 0.01 l/min, respectively). Following sPLM, MAP fell similarly (5 ± 2 mmHg; P = 0.8), but neither HR nor CO responses were identifiable. The peak LBF and LVC response was similar for PLM (993 ± 189 ml/min; 11.9 ± 1.5 ml·min -1 ·mmHg -1 , respectively) and sPLM (878 ± 119 ml/min; 10.9 ± 1.6 ml·min -1 ·mmHg -1 , respectively). Thus sPLM represents a variant of the PLM approach to assess vascular function that is more easily performed and evokes a peripheral stimulus that induces a significant hyperemia, but does not generate a potentially confounding, chronotropic response, which may make sPLM more useful clinically. Using the single passive leg movement (PLM) technique, a variant of the vascular function assessment PLM, we have identified a novel peripheral vascular assessment method that is more easily performed than PLM, which, by not evoking potentially confounding central hemodynamic responses, may be more useful clinically.

2011 Vascular Research Initiatives Conference: basic foundations of translational research in vascular disease.

PubMed

Ziegler, Kenneth R; Dardik, Alan

2011-07-01

The Vascular Research Initiatives Conference (VRIC) is an annual conference organized by the Society for Vascular Surgery (SVS). The 2011 VRIC was held in Chicago (IL, USA) to precede and coincide with the first day of the meeting of the Council on Arteriosclerosis, Thrombosis and Vascular Biology (ATVB) of the American Heart Association. The event is designed to present world class vascular research results, encourage collaboration between vascular surgeons and basic scientists in related disciplines, as well as to stimulate interest in research among aspiring academic vascular surgeons. The 2011 VRIC featured plenary sessions addressing peripheral arterial disease, vascular endothelium and thrombosis, aneurysms, and stem cells and tissue engineering. Recipients of the SVS partner grants with the National Institutes of Health K08 awardees presented their progress reports, and keynote addresses were given by Linda Graham and Frank LoGerfo.

Effect of long-term hydroxychloroquine on vascular events in patients with systemic lupus erythematosus: a database prospective cohort study.

PubMed

Hsu, Chung-Yuan; Lin, Yu-Sheng; Su, Yu-Jih; Lin, Hsing-Fen; Lin, Ming-Shyan; Syu, Ya-Jhu; Cheng, Tien-Tsai; Yu, Shan-Fu; Chen, Jia-Feng; Chen, Tien-Hsing

2017-12-01

The incidence of thromboembolism in patients with SLE is higher than that in the general population. HCQ, widely used to treat lupus, may have vascular protective effects. The aim of this study was to determine whether long-term HCQ exposure is associated with decreased thromboembolism risk in SLE. We designed a prospective cohort study within an SLE population based on the National Health Insurance Research Database in Taiwan. We divided participants into HCQ and control groups according to HCQ prescription during the first year. These groups were defined by medication possession ratio (MPR) ⩾80% and MPR = 0%, respectively. Patients with an MPR between 0 and 80% were excluded. The primary outcome was a composite vascular event, including acute coronary syndrome, ischaemic stroke, pulmonary embolism, deep vein thrombosis and peripheral arterial disease 1 year after inclusion. We excluded patients from the cohort if they had outcomes within the first year. A total of 8397 patients were eligible for analysis. After propensity-score matching, we included 1946 patients in each group. During a mean follow-up of 7.4 years, the number of events was 139 in the HCQ group (7.1%) and 149 in the control group (7.7%). The risk of vascular events in the HCQ group was similar to that in the control group (hazard ratio = 0.91; 95% CI: 0.72, 1.15). Further subgroup analyses confirmed no statistically significant differences between the groups. Long-term HCQ appears to have no vascular protective effect in patients with SLE. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Feasibility of a clinical trial to assess the effect of dietary calcium v. supplemental calcium on vascular and bone markers in healthy postmenopausal women.

PubMed

Ong, Angel M; Weiler, Hope A; Wall, Michelle; Haddad, Rouba; Gorgui, Jessica; Daskalopoulou, Stella S; Goltzman, David; Morin, Suzanne N

2016-07-01

Whether supplemental Ca has similar effects to dietary Ca on vascular and bone markers is unknown. The present trial investigated the feasibility of applying dietary and supplemental interventions in a randomised-controlled trial (RCT) aiming to estimate the effect of supplemental Ca as compared with dietary Ca on vascular and bone markers in postmenopausal women. In total, thirteen participants were randomised to a Ca supplement group (CaSuppl) (750 mg Ca from CaCO3+450 mg Ca from food+20 µg vitamin D supplement) or a Ca diet group (CaDiet) (1200 mg Ca from food+10 µg vitamin D supplement). Participants were instructed on Ca consumption targets at baseline. Monthly telephone follow-ups were conducted to assess adherence to interventions (±20 % of target total Ca) using the multiple-pass 24-h recall method and reported pill count. Measurements of arterial stiffness, peripheral blood pressure and body composition were performed at baseline and after 6 and 12 months in all participants who completed the trial (n 9). Blood and serum biomarkers were measured at baseline and at 12 months. Both groups were compliant to trial interventions (±20 % of target total Ca intake; pill count ≥80 %). CaSuppl participants maintained a significantly lower average dietary Ca intake compared with CaDiet participants throughout the trial (453 (sd 187) mg/d v. 1241 (sd 319) mg/d; P<0·001). There were no significant differences in selected vascular outcomes between intervention groups over time. Our pilot trial demonstrated the feasibility of conducting a large-scale RCT to estimate the differential effects of supplemental and dietary Ca on vascular and bone health markers in healthy postmenopausal women.

[Atherectomy for peripheral arterial disease].

PubMed

Londero, Louise Skovgaard; Høgh, Annette Langager; Lindholt, Jes Sanddal

2015-04-13

Symptomatic peripheral arterial disease is managed according to national and international guidelines and the number of vascular reconstructions performed each year has increased over the past decade mainly due to an increasing frequency of endovascular procedures. Atherectomy as an alternative to the established treatment of symptomatic peripheral arterial disease has recently been analysed in a Cochrane review. In Denmark, atherectomy is not performed and so far the evidence is poor as the method is not an alternative to the established treatment in this country.

Progression of Diabetic Capillary Occlusion: A Model

PubMed Central

Gens, John Scott; Glazier, James A.; Burns, Stephen A.; Gast, Thomas J.

2016-01-01

An explanatory computational model is developed of the contiguous areas of retinal capillary loss which play a large role in diabetic maculapathy and diabetic retinal neovascularization. Strictly random leukocyte mediated capillary occlusion cannot explain the occurrence of large contiguous areas of retinal ischemia. Therefore occlusion of an individual capillary must increase the probability of occlusion of surrounding capillaries. A retinal perifoveal vascular sector as well as a peripheral retinal capillary network and a deleted hexagonal capillary network are modelled using Compucell3D. The perifoveal modelling produces a pattern of spreading capillary loss with associated macular edema. In the peripheral network, spreading ischemia results from the progressive loss of the ladder capillaries which connect peripheral arterioles and venules. System blood flow was elevated in the macular model before a later reduction in flow in cases with progression of capillary occlusions. Simulations differing only in initial vascular network structures but with identical dynamics for oxygen, growth factors and vascular occlusions, replicate key clinical observations of ischemia and macular edema in the posterior pole and ischemia in the retinal periphery. The simulation results also seem consistent with quantitative data on macular blood flow and qualitative data on venous oxygenation. One computational model applied to distinct capillary networks in different retinal regions yielded results comparable to clinical observations in those regions. PMID:27300722

Peripheral atherectomy practice patterns in the United States from the Vascular Quality Initiative.

PubMed

Mohan, Sathish; Flahive, Julie M; Arous, Edward J; Judelson, Dejah R; Aiello, Francesco A; Schanzer, Andres; Simons, Jessica P

2018-06-21

Peripheral atherectomy has been shown to have technical success in single-arm studies, but clinical advantages over angioplasty and stenting have not been demonstrated, leaving its role unclear. We sought to describe patterns of atherectomy use in a real-world U.S. cohort to understand how it is currently being applied. The Vascular Quality Initiative was queried to identify all patients who underwent peripheral vascular intervention from January 2010 to September 2016. Descriptive statistics were performed to analyze demographics of the patients, comorbidities, indication, treatment modalities, and lesion characteristics. The intermittent claudication (IC) and critical limb ischemia (CLI) cohorts were analyzed separately. Of 85,605 limbs treated, treatment indication was IC in 51% (n = 43,506) and CLI in 49% (n = 42,099). Atherectomy was used in 15% (n = 13,092) of cases, equivalently for IC (15%; n = 6674) and CLI (15%; n = 6418). There was regional variation in use of atherectomy, ranging from a low of 0% in one region to a high of 32% in another region. During the study period, there was a significant increase in the proportion of cases that used atherectomy (11% in 2010 vs 18% in 2016; P < .0001). Compared with nonatherectomy cases, those with atherectomy use had higher incidence of prior peripheral vascular intervention (IC, 55% vs 43% [P < .0001]; CLI, 47% vs 41% [P < .0001]), greater mean number of arteries treated (IC, 1.8 vs 1.6 [P < .0001]; CLI, 2.1 vs 1.7 [P < .0001]), and lower proportion of prior leg bypass (IC, 10% vs 14% [P < .0001]; CLI, 11% vs 17% [P < .0001]). There was lower incidence of failure to cross the lesion (IC, 1% vs 4% [P < .0001]; CLI, 4% vs 7% [P < .0001]) but higher incidence of distal embolization (IC, 1.9% vs 0.8% [P < .0001]; CLI, 3.0% vs 1.4% [P < .0001]) and, in the CLI cohort, arterial perforation (1.4% vs 1.0%; P = .01). Despite a lack of evidence for atherectomy over angioplasty and stenting, its use has increased across the United States from 2010 to 2016. It is applied equally to IC and CLI populations, with no identifiable pattern of comorbidities or lesion characteristics, suggesting that indications are not clearly delineated or agreed on. This study places impetus on further understanding of the optimal role for atherectomy and its long-term clinical benefit in the management of peripheral arterial disease. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Sex, ageing and resting blood pressure: gaining insights from the integrated balance of neural and haemodynamic factors.

PubMed

Hart, Emma C; Joyner, Michael J; Wallin, B Gunnar; Charkoudian, Nisha

2012-05-01

Young women tend to have lower blood pressure, and less risk of hypertension, compared to young men. As people age, both blood pressure and the risk of hypertension increase in both sexes; this occurs most strikingly in women after menopause. However, the mechanisms for these influences of sex and age remain incompletely understood. In this review we are specifically interested in the interaction between neural (sympathetic nerve activity; SNA) and haemodynamic factors (cardiac output, blood pressure and vascular resistance) and how these change with sex and age. While peripheral vascular SNA can vary 7- to 10-fold among normotensive young men and women, it is reproducible in a given individual. Surprisingly, higher levels of SNA are not associated with higher blood pressures in these groups. In young men, high SNA is associated with higher total peripheral vascular resistance (TPR), and appears to be balanced by lower cardiac output and less peripheral vascular responsiveness to adrenergic stimulation. Young women do not exhibit the SNA-TPR relationship. Recent evidence suggests that β-adrenergic vasodilatation offsets the vasoconstrictor effects of α-adrenergic vasoconstriction in young women, which may contribute to the generally lower blood pressures in this group. Sympathetic nerve activity increases with age, and in groups over 40, levels of SNA are more tightly linked to levels of blood pressure. The potentially protective β-adrenergic effect seen in young women appears to be lost after menopause and probably contributes to the increased blood pressure and increased risk of hypertension seen in older women.

N-acetylcysteine improves coronary and peripheral vascular function.

PubMed

Andrews, N P; Prasad, A; Quyyumi, A A

2001-01-01

We investigated whether N-acetylcysteine (NAC), a reduced thiol that modulates redox state and forms adducts of nitric oxide (NO), improves endothelium-dependent vasomotion. Coronary atherosclerosis is associated with endothelial dysfunction and reduced NO activity. In 16 patients undergoing cardiac catheterization, seven with and nine without atherosclerosis, we assessed endothelium-dependent vasodilation with acetylcholine (ACH) and endothelium-independent vasodilation with nitroglycerin (NTG) and sodium nitroprusside (SNP) before and after intracoronary NAC. In 14 patients femoral vascular responses to ACH, NTG and SNP were measured before and after NAC. Intraarterial NAC did not change resting coronary or peripheral vascular tone. N-acetylcysteine potentiated ACH-mediated coronary vasodilation; coronary blood flow was 36 +/- 11% higher (p < 0.02), and epicardial diameter changed from -1.2 +/- 2% constriction to 4.7 +/- 2% dilation after NAC (p = 0.03). Acetylcholine-mediated femoral vasodilation was similarly potentiated by NAC (p = 0.001). Augmentation of the ACH response was similar in patients with or without atherosclerosis. N-acetylcysteine did not affect NTG-mediated vasodilation in either the femoral or coronary circulations and did not alter SNP responses in the femoral circulation. In contrast, coronary vasodilation with SNP was significantly greater after NAC (p < 0.05). Thiol supplementation with NAC improves human coronary and peripheral endothelium-dependent vasodilation. Nitroglycerin responses are not enhanced, but SNP-mediated responses are potentiated only in the coronary circulation. These NO-enhancing effects of thiols reflect the importance of the redox state in the control of vascular function and may be of therapeutic benefit in treating acute and chronic manifestations of atherosclerosis.

[Peripheral arterial thromboembolism in Crohn's disease].

PubMed

Ferrer, Isabel; Benavent, Guillem; Bastida, Guillermo; Arnau, Miguel Ángel; Iborra, Marisa; Beltrán, Belén; Aguas, Mariam; Hinojosa, Joaquín; Nos, Pilar

2013-01-01

Inflammatory Bowel Disease (IBD) usually affects the gastrointestinal tract, although some patients can also develop extraintestinal manifestations, such as vascular symptoms both venous and arterial ones. The former being more frequent than the latter. We report the case of a 62-year-old male, diagnosed of Crohńs disease (CD) (A3,L1+L4,B3), admitted to hospital for treatment of a retroperitoneal abscess. He presented a peripheral arterial thromboembolism during his stay, which required urgent embolectomy. After anticoagulation with low-molecular-weight heparin (LMWH), vascular magnetic resonance imaging revealed a large thrombus involving the descent aorta, which was solved with surgery and long-term anticoagulation. Peripheral arterial thrombosis is a rare extraintestinal manifestation of IBD. Nevertheless it is always important to consider it in patients with IBD. Prophylactic treatment should be made with low-molecular-weight heparin (LMWH) and definitive treatment with a combination of LMWH and surgery. Copyright © 2012 Elsevier España, S.L. and AEEH y AEG. All rights reserved.

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.

Msx1 and Msx2 are expressed in sub-populations of vascular smooth muscle cells.

PubMed

Goupille, Olivier; Saint Cloment, Cécile; Lopes, Miguel; Montarras, Didier; Robert, Benoît

2008-08-01

Using an nlacZ reporter gene inserted at the Msx1 and Msx2 loci, we could analyze the expression of these homeogenes in the adult mouse. We observed that Msx genes are prominently expressed in a subset of blood vessels. The Msx2nlacZ allele is mainly expressed in a restricted population of mural cells in peripheral arteries and veins. Msx1nlacZ is expressed to a lesser extent by vascular smooth muscle cells of peripheral arteries, but is highly expressed in arterioles and capillaries, making Msx1 a novel marker for a subpopulation of pericytes. Expression is set up early in developing vessels and maintained throughout life. In addition, expression of both genes is observed in a few endothelial cells of the aorta at fetal stages, and only Msx2 continues to be expressed in this layer at the adult stage. These results suggest major functions for Msx genes in vascular mural cell formation and remodeling. Copyright (c) 2008 Wiley-Liss, Inc.

(18)F-sodium fluoride PET/CT for the in vivo visualization of Mönckeberg's sclerosis in a diabetic patient.

PubMed

Quirce, R; Martínez-Rodríguez, I; Banzo, I; de Arcocha-Torres, M; Jiménez-Bonilla, J F; Martínez-Amador, N; Ibáñez-Bravo, S; Ramos, L; Amado, J A; Carril, J M

2015-01-01

Diabetes is a major frequent cause of atherosclerosis vascular disease. Arterial calcification in diabetic patients is responsible for peripheral vascular involvement. Molecular imaging using (18)F-sodium fluoride ((18)F-NaF) positron emission tomography (PET)/computed tomography (CT) has been recently proposed as a marker to study the in vivo mineralization process in the atheroma plaque. A 69-year-old man with a history of type 2 diabetes and no clinical evidence of peripheral arterial disease underwent an (18)F-NaF PET/CT scan. A linear, well-defined (18)F-NaF uptake was detected along the femoral arteries. In addition, the CT component of the PET/CT identified an unsuspected "tram-track" calcification in his femoral arteries, suggestive of medial calcification (Mönckeberg's sclerosis). In other vascular territories, focal (18)F-NaF uptake was also detected in carotid and aorta atheroma plaques. Molecular imaging with (18)F-NaF PET/CT might provide new functional information about the in vivo vascular calcification process in diabetic patients. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

[Peripheral MR angiography without contrast agent using fresh blood imaging (FBI) with ECG-trigger: initial experience].

PubMed

Xia, Chun-Chao; Li, Zhen-Lin; Chen, Xian; Sun, Jia-Yu; Li, Chang-Xian; Tang, He-Han; Yuan, Yuan; Song, Bin

2012-07-01

To examine the efficacy of fresh blood imaging (FBI) in detecting vascular diseases in lower extremity. Thirty-six patients suspected of having lower extremity vascular diseases were imaged with a 1.5-T MRI system (Toshiba Excelart Vantage). Contrast-enhanced MRA (CEMRA) and FBI technology, with maximum intensity projection (MIP) reconstruction were adopted to visualize lower extremity vascular. Signal to noise ratios (SNR) were measured on the FBI and CEMRA images. Two experienced radiologists assessed the imaging quality of peripheral artery MRA on MIP reconstructed images. All patients successfully underwent both FBI and CEMRA. All arterial segments were obtained in the 36 patients. The SNR values on FBI and CEMRA were 108.39 +/- 9.76 and 87.46 +/- 14.77 (t = - 6.782, P = 0.001), respectively. There were no significant differences in the overall image quality, arterial anatomy and venous overlap (chi2 = 0.004, P = 0.947; chi2 = 0.000, P = 1; chi2 = 0.681, P = 0.409). The CEMRA motion artifacts were less than FBI (chi2 = 8.744, P = 0.03). The FBI technique, which shows the vascular disease in lower extremity without contrast medium with ECG gating, is considered clinically useful.

A balloon-expandable sheath facilitates transfemoral TAVR in patients with peripheral vascular disease and tortuosity.

PubMed

Goldsweig, Andrew M; Faheem, Osman; Cleman, Michael W; Forrest, John K

2015-06-01

We sought to perform transcatheter aortic valve replacement (TAVR) via the transfemoral approach in patients with peripheral arterial disease (PAD), small caliber ileofemoral vessels and vascular tortuosity. For patients with increased surgical risk, TAVR is associated with a higher 1-year survival rate than surgical aortic valve replacement (SAVR). Transfemoral vascular access for TAVR results in superior outcomes versus procedures performed via other routes in terms of mortality, morbidity and healthcare economics. In many patients, the ability to safely perform the procedure via the transfemoral approach is limited by narrow, diseased and tortuous ileofemoral vasculature. We employed the SoloPath Balloon Expandable TransFemoral Access System (Terumo Med. Corp., Tokyo, Japan) to perform transfemoral TAVR in five patients with PAD, small caliber ileofemoral vessels and vascular tortuosity. We report our experience using this balloon-expandable sheath during 5 cases of transfemoral TAVR in patients with inhospitable ileofemoral vasculature of mean diameter ⩽ 5.8 mm. The unexpanded sheath's malleable structure and hydrophilic coating permitted deployment despite severe stenoses and tortuosity. Subsequent inflation to 18 Fr facilitated successful TAVR. Postprocedural angiography demonstrated no significant vascular access complications. In one case, the entire procedure was performed percutaneously, without common femoral artery surgical cutdown. The SoloPath sheath system permits transfemoral TAVR in patients with PAD small caliber ileofemoral vessels and vascular tortuosity. The transfemoral balloon-expandable sheath allowed these patients to avoid the increased morbidity and mortality risks associated with direct aortic or transapical access. © The Author(s), 2015.

Preoperative frailty assessment predicts loss of independence after vascular surgery.

PubMed

Donald, Graham W; Ghaffarian, Amir A; Isaac, Farid; Kraiss, Larry W; Griffin, Claire L; Smith, Brigitte K; Sarfati, Mark R; Beckstrom, Julie L; Brooke, Benjamin S

2018-05-14

Frailty, a clinical syndrome associated with loss of metabolic reserves, is prevalent among patients who present to vascular surgery clinics for evaluation. The Clinical Frailty Scale (CFS) is a rapid assessment method shown to be highly specific for identifying frail patients. In this study, we sought to evaluate whether the preoperative CFS score could be used to predict loss of independence after major vascular procedures. We identified all patients living independently at home who were prospectively assessed using the CFS before undergoing an elective major vascular surgery procedure (admitted for >24 hours) at an academic medical center between December 2015 and December 2017. Patient- and procedure-level clinical data were obtained from our institutional Vascular Quality Initiative registry database. The composite outcome of discharge to a nonhome location or 30-day mortality was evaluated using bivariate and multivariate regression models. A total of 134 independent patients were assessed using the CFS before they underwent elective open abdominal aortic aneurysm repair (8%), endovascular aneurysm repair (26%), thoracic endovascular aortic repair (6%), suprainguinal bypass (6%), infrainguinal bypass (16%), carotid endarterectomy (19%), or peripheral vascular intervention (20%). Among 39 (29%) individuals categorized as being frail using the CFS, there was no significant difference in age or ASA physical status compared with nonfrail patients. However, frail patients were significantly more likely to need mobility assistance after surgery (62% frail vs 22% nonfrail; P < .01) and to be discharged to a nonhome location (22% frail vs 6% nonfrail; P = .01) or to die within 30 days after surgery (8% frail vs 0% nonfrail; P < .01). Preoperative frailty was associated with a >12-fold higher risk (odds ratio, 12.1; 95% confidence interval, 2.17-66.96; P < .01) of 30-day mortality or loss of independence, independent of the vascular procedure undertaken. The CFS is a practical tool for assessing preoperative frailty among patients undergoing elective major vascular surgery and can be used to predict likelihood of requiring discharge to a nursing facility or death after surgery. The identification of frail patients before major surgery can help manage postoperative expectations and optimize transitions of care. Published by Elsevier Inc.

A practical method to rapidly dissolve metallic stents.

PubMed

Bradshaw, Scott H; Kennedy, Lloyd; Dexter, David F; Veinot, John P

2009-01-01

Metallic stents are commonly used in many clinical applications including peripheral vascular disease intervention, biliary obstruction, endovascular repair of aneurysms, and percutaneous coronary interventions. In the examination of vascular stent placement, it is important to determine if the stent is open or has become obstructed. This is increasingly important in the era of drug-eluting stent usage in coronary arteries. We describe a practical, rapid and cost-effective method to dissolve most metallic stents leaving the vascular and luminal tissues intact. This practical method may replace the laborious and expensive plastic embedding methods currently utilized.

Divergent metabolome and proteome suggest functional independence of dual phloem transport systems in cucurbits

PubMed Central

Zhang, Baichen; Tolstikov, Vladimir; Turnbull, Colin; Hicks, Leslie M.; Fiehn, Oliver

2010-01-01

Cucurbitaceous plants (cucurbits) have long been preferred models for studying phloem physiology. However, these species are unusual in that they possess two different phloem systems, one within the main vascular bundles [fascicular phloem (FP)] and another peripheral to the vascular bundles and scattered through stem and petiole cortex tissues [extrafascicular phloem (EFP)]. We have revisited the assumption that the sap released after shoot incision originates from the FP, and also investigated the long-standing question of why the sugar content of this sap is ~30-fold less than predicted for requirements of photosynthate delivery. Video microscopy and phloem labeling experiments unexpectedly reveal that FP very quickly becomes blocked upon cutting, whereas the extrafascicular phloem bleeds for extended periods. Thus, all cucurbit phloem sap studies to date have reported metabolite, protein, and RNA composition and transport in the relatively minor extrafascicular sieve tubes. Using tissue dissection and direct sampling of sieve tube contents, we show that FP in fact does contain up to 1 M sugars, in contrast to low-millimolar levels in the EFP. Moreover, major phloem proteins in sieve tubes of FP differ from those that predominate in the extrafascicular sap, and include several previously uncharacterized proteins with little or no homology to databases. The overall compositional differences of the two phloem systems strongly indicate functional isolation. On this basis, we propose that the fascicular phloem is largely responsible for sugar transport, whereas the extrafascicular phloem may function in signaling, defense, and transport of other metabolites. PMID:20566864

Low Volume Resuscitation with Cell Impermeants

DTIC Science & Technology

2016-04-01

to rise) and a fall in peripheral vascular resistance . In this model, hemorrhage and blood loss was controlled so any changes in hemoglobin...appealing. The increase in capillary filling together with reduced resistance to flow in these peripheral beds leads to increased blood flow and oxygen...delivery. The low resistance , compared to saline controls, likely represents a physical decompression of the capillary beds by controlling cell and

Ethnic differences in the +405 and -460 vascular endothelial growth factor polymorphisms and peripheral neuropathy in patients with diabetes residing in a North London, community in the United Kingdom.

PubMed

Zitouni, Karima; Tinworth, Lorna; Earle, Kenneth Anthony

2017-06-29

There are marked ethnic differences in the susceptibility to the long-term diabetic vascular complications including sensory neuropathy. The vascular endothelial growth factor (VEGF) +405 (C/G) and -460 (T/C) polymorphisms are associated with retinopathy and possibly with nephropathy, however no information is available on their relationship with peripheral neuropathy. Therefore, we examined the prevalence of these VEGF genotypes in a multi-ethnic cohort of patients with diabetes and their relationship with evident peripheral diabetic neuropathy. In the current investigation, we studied 313 patients with diabetes mellitus of African-Caribbean, Indo-Asian and Caucasian ethnic origin residing in an inner-city community in London, United Kingdom attending a single secondary care centre. Genotyping was performed for the VEGF +405 and VEGF -460 polymorphisms using a pyrosequencing technique. Forty-nine patients (15.6%) had clinical evidence of peripheral neuropathy. Compared to Caucasian patients, African-Caribbean and Indo-Asian patients had lower incidence of neuropathy (24.6%, 14.28%, 6.7%, respectively; P = 0.04). The frequency of the VEGF +405 GG genotype was more common in Indo-Asian patients compared to African-Caribbean and Caucasian patients (67.5%, 45.3%, 38.4%, respectively; p ≤ 0.02). The G allele was more common in patients with type 2 diabetes of Indo-Asian origin compared to African-Caribbean and Caucasian origin (p ≤ 0.02). There was no difference between the ethnic groups in VEGF -460 genotypes. The distributions of the VEGF +405 and VEGF -460 genotypes were similar between the diabetic patients with and without neuropathy. In this cohort of patients, VEGF +405 and VEGF -460 polymorphisms were not associated with evident diabetic peripheral neuropathy, however an association was found between VEGF +405 genotypes and Indo-Asian which might have relevance to their lower rates of ulceration and amputation. This finding highlights the need for further investigation of any possible relationship between VEGF genotype, circulating VEGF concentrations and differential vulnerability to peripheral neuropathy amongst diabetic patients of different ethnic backgrounds.

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. Copyright © 2016 the American Physiological Society.

Predictive Value of Reactive Hyperemia for Cardiovascular Events in Patients With Peripheral Arterial Disease Undergoing Vascular Surgery

PubMed Central

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

2008-01-01

Objective Reactive hyperemia is the compensatory increase in blood flow that occurs after a period of tissue ischemia, and this response is blunted in patients with cardiovascular risk factors. The predictive value of reactive hyperemia for cardiovascular events in patients with atherosclerosis and the relative importance of reactive hyperemia compared with other measures of vascular function have not been previously studied. Methods and Results We prospectively measured reactive hyperemia and brachial artery flow-mediated dilation by ultrasound in 267 patients with peripheral arterial disease referred for vascular surgery (age 66±11 years, 26% female). Median follow-up was 309 days (range 1 to 730 days). Fifty patients (19%) had an event, including cardiac death (15), myocardial infarction (18), unstable angina (8), congestive heart failure (6), and nonhemorrhagic stroke (3). Patients with an event were older and had lower hyperemic flow velocity (75±39 versus 95±50 cm/s, P=0.009). Patients with an event also had lower flow-mediated dilation (4.5±3.0 versus 6.9±4.6%, P<0.001), and when these 2 measures of vascular function were included in the same Cox proportional hazards model, lower hyperemic flow (OR 2.7, 95% CI 1.2 to 5.9, P=0.018) and lower flow-mediated dilation (OR 4.2, 95% CI: 1.8 to 9.8, P=0.001) both predicted cardiovascular events while adjusting for other risk factors. Conclusions Thus, lower reactive hyperemia is associated with increased cardiovascular risk in patients with peripheral arterial disease. Furthermore, flow-mediated dilation and reactive hyperemia incrementally relate to cardiovascular risk, although impaired flow-mediated dilation was the stronger predictor in this population. These findings further support the clinical relevance of vascular function measured in the microvasculature and conduit arteries in the upper extremity. PMID:17717291

Patterns of peripheral retinal and central macula ischemia in diabetic retinopathy as evaluated by ultra-widefield fluorescein angiography.

PubMed

Sim, Dawn A; Keane, Pearse A; Rajendram, Ranjan; Karampelas, Michael; Selvam, Senthil; Powner, Michael B; Fruttiger, Marcus; Tufail, Adnan; Egan, Catherine A

2014-07-01

To investigate the association between peripheral and central ischemia in diabetic retinopathy. Retrospective, cross-sectional. Consecutive ultra-widefield fluorescein angiography images were collected from patients with diabetes over a 12-month period. Parameters quantified include the foveal avascular zone (FAZ) area, peripheral ischemic index, peripheral leakage index, and central retinal thickness measurements, as well as visual acuity. The peripheral ischemia or leakage index was calculated as the area of capillary nonperfusion or leakage, expressed as a percentage of the total retinal area. Forty-seven eyes of 47 patients were included. A moderate correlation was observed between the peripheral ischemia index and FAZ area (r = 0.49, P = .0001). A moderate correlation was also observed between the peripheral leakage index and FAZ area, but only in eyes that were laser naïve (r = 0.44, P = .02). A thinner retina was observed in eyes with macular ischemia (217 ± 81.8 μm vs 272 ± 36.0 μm) (P = .02), but not peripheral ischemia (258 ± 76.3 μm vs 276 ± 68.0 μm) (P = .24). The relationships between different patterns of peripheral and central macular pathology and visual acuity were evaluated in a step-wise multivariable regression model, and the variables that remained independently associated were age (r = 0.33, P = .03), FAZ area (r = 0.45, P = .02), and central retinal thickness (r = 0.38, P = .01), (R(2)-adjusted = 0.36). Ultra-widefield fluorescein angiography provides an insight into the relationships between diabetic vascular complications in the retinal periphery and central macula. Although we observed relationships between ischemia and vascular leakage in the macula and periphery, it was only macular ischemia and retinal thinning that was independently associated with a reduced visual function. Copyright © 2014 Elsevier Inc. All rights reserved.

Vascularized nerve graft: a clinical contribution.

PubMed

Luchetti, R; De Santis, G; Soragni, O; Deluca, S; Pederzini, L; Alfarano, M; Landi, A

1990-01-01

The authors present 4 cases of vascularized nerve graft. The results were better than those obtained with traditional grafting. The indication is a rare one, and the experimental results are contradictory. Indications are limited to Volkmann ischemic syndromes, post-actinic lesions of the brachial plexus, infections and finally, post-burning scarring. Nevertheless, traditional nerve grafts remain the treatment of choice for peripheral nerve lesions which cannot undergo direct suturing.

[Peripheral vascular injuries in polytrauma].

PubMed

Richter, A; Silbernik, D; Oestreich, K; Karaorman, M; Storz, L W

1995-09-01

Between 1972 und 1993 a total of 68 patients were treated at the Department of Surgery of the University Clinic of Mannheim for peripheral vascular injury resulting from multiple trauma. The average age of these patients was 31.3 years, and most of them were male (88.2%; n = 60). The injured vessels were localized evenly in all the extremities: 31 patients (45.5%) presented with arterial damage of the upper extremity, and 37 (54.5%) showed lesions along the femoro-popliteal arteries. The most frequent location of injured vessels in the multiply traumatized patient was the popliteal artery (n = 18, 26.5%), the distal part of the superficial femoral artery (n = 12, 17.6%), the brachial artery (n = 14, 20.6%) and the axillary artery (n = 10, 14.6%). The dominant cause, of trauma was road traffic accidents (72%), and 20 patients (29%) acquired their vascular injuries as motorcyclists. There were also 13 occupational accidents (19%) involving vascular injuries. In addition to a vascular trauma 34 patients (50%) had complicated fractures, and a further 34 patients (50%) had multiple fractures: 12 (17.6%) had head and brain damage, 5 (7.3%) had blunt abdominal trauma and 6 (8.8%) had blunt thoracic injury. The general amputation rate was 2.9% (n = 2). One patient died on the table of a torn off subclavian artery combined with multiple other injuries. Paresis of the plexus is a particular problem after vascular lesions of the upper extremity: in 22 patients (71%) paresis of the plexus persisted after successful vascular reconstruction (follow-up period between 3 months and 16 years, median time 3.45 years).(ABSTRACT TRUNCATED AT 250 WORDS)

Vascular tone pathway polymorphisms in relation to primary open-angle glaucoma.

PubMed

Kang, J H; Loomis, S J; Yaspan, B L; Bailey, J C; Weinreb, R N; Lee, R K; Lichter, P R; Budenz, D L; Liu, Y; Realini, T; Gaasterland, D; Gaasterland, T; Friedman, D S; McCarty, C A; Moroi, S E; Olson, L; Schuman, J S; Singh, K; Vollrath, D; Wollstein, G; Zack, D J; Brilliant, M; Sit, A J; Christen, W G; Fingert, J; Forman, J P; Buys, E S; Kraft, P; Zhang, K; Allingham, R R; Pericak-Vance, M A; Richards, J E; Hauser, M A; Haines, J L; Wiggs, J L; Pasquale, L R

2014-06-01

Vascular perfusion may be impaired in primary open-angle glaucoma (POAG); thus, we evaluated a panel of markers in vascular tone-regulating genes in relation to POAG. We used Illumina 660W-Quad array genotype data and pooled P-values from 3108 POAG cases and 3430 controls from the combined National Eye Institute Glaucoma Human Genetics Collaboration consortium and Glaucoma Genes and Environment studies. Using information from previous literature and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, we compiled single-nucleotide polymorphisms (SNPs) in 186 vascular tone-regulating genes. We used the 'Pathway Analysis by Randomization Incorporating Structure' analysis software, which performed 1000 permutations to compare the overall pathway and selected genes with comparable randomly generated pathways and genes in their association with POAG. The vascular tone pathway was not associated with POAG overall or POAG subtypes, defined by the type of visual field loss (early paracentral loss (n=224 cases) or only peripheral loss (n=993 cases)) (permuted P≥0.20). In gene-based analyses, eight were associated with POAG overall at permuted P<0.001: PRKAA1, CAV1, ITPR3, EDNRB, GNB2, DNM2, HFE, and MYL9. Notably, six of these eight (the first six listed) code for factors involved in the endothelial nitric oxide synthase activity, and three of these six (CAV1, ITPR3, and EDNRB) were also associated with early paracentral loss at P<0.001, whereas none of the six genes reached P<0.001 for peripheral loss only. Although the assembled vascular tone SNP set was not associated with POAG, genes that code for local factors involved in setting vascular tone were associated with POAG.

Biophysical markers of the peripheral vasoconstriction response to pain in sickle cell disease

PubMed Central

Khaleel, Maha; Sunwoo, John; Shah, Payal; Detterich, Jon A.; Kato, Roberta M.; Thuptimdang, Wanwara; Meiselman, Herbert J.; Sposto, Richard; Tsao, Jennie; Wood, John C.; Zeltzer, Lonnie; Coates, Thomas D.; Khoo, Michael C. K.

2017-01-01

Painful vaso-occlusive crisis (VOC), a complication of sickle cell disease (SCD), occurs when sickled red blood cells obstruct flow in the microvasculature. We postulated that exaggerated sympathetically mediated vasoconstriction, endothelial dysfunction and the synergistic interaction between these two factors act together to reduce microvascular flow, promoting regional vaso-occlusions, setting the stage for VOC. We previously found that SCD subjects had stronger vasoconstriction response to pulses of heat-induced pain compared to controls but the relative degrees to which autonomic dysregulation, peripheral vascular dysfunction and their interaction are present in SCD remain unknown. In the present study, we employed a mathematical model to decompose the total vasoconstriction response to pain into: 1) the neurogenic component, 2) the vascular response to blood pressure, 3) respiratory coupling and 4) neurogenic-vascular interaction. The model allowed us to quantify the contribution of each component to the total vasoconstriction response. The most salient features of the components were extracted to represent biophysical markers of autonomic and vascular impairment in SCD and controls. These markers provide a means of phenotyping severity of disease in sickle-cell anemia that is based more on underlying physiology than on genotype. The marker of the vascular component (BMv) showed stronger contribution to vasoconstriction in SCD than controls (p = 0.0409), suggesting a dominant myogenic response in the SCD subjects as a consequence of endothelial dysfunction. The marker of neurogenic-vascular interaction (BMn-v) revealed that the interaction reinforced vasoconstriction in SCD but produced vasodilatory response in controls (p = 0.0167). This marked difference in BMn-v suggests that it is the most sensitive marker for quantifying combined alterations in autonomic and vascular function in SCD in response to heat-induced pain. PMID:28542469

76 FR 78216 - Organ Procurement and Transplantation Network

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-16

... composite tissue allograft; however, for the purposes of rulemaking, the Health Resources and Services..., Hand transplantation and vascularized composite tissue allografts in orthopaedics and traumatology... vascularized composite allografts, described below, within the definition of organs covered by the rules...

Effects of antibacterial nanostructured composite films on vascular stents: hemodynamic behaviors, microstructural characteristics, and biomechanical properties.

PubMed

Cheng, Han-Yi; Hsiao, Wen-Tien; Lin, Li-Hsiang; Hsu, Ya-Ju; Sinrang, Andi Wardihan; Ou, Keng-Liang

2015-01-01

The purpose of this research was to investigate stresses resulting from different thicknesses and compositions of hydrogenated Cu-incorporated diamond-like carbon (a-C:H/Cu) films at the interface between vascular stent and the artery using three-dimensional reversed finite element models (FEMs). Blood flow velocity variation in vessels with plaques was examined by angiography, and the a-C:H/Cu films were characterized by transmission electron microscopy to analyze surface morphology. FEMs were constructed using a computer-aided reverse design system, and the effects of antibacterial nanostructured composite films in the stress field were investigated. The maximum stress in the vascular stent occurred at the intersections of net-like structures. Data analysis indicated that the stress decreased by 15% in vascular stents with antibacterial nanostructured composite films compared to the control group, and the stress decreased with increasing film thickness. The present results confirmed that antibacterial nanostructured composite films improve the biomechanical properties of vascular stents and release abnormal stress to prevent restenosis. The results of the present study offer the clinical benefit of inducing superior biomechanical behavior in vascular stents. © 2014 Wiley Periodicals, Inc.

4D phase contrast flow imaging for in-stent flow visualization and assessment of stent patency in peripheral vascular stents--a phantom study.

PubMed

Bunck, Alexander C; Jüttner, Alena; Kröger, Jan Robert; Burg, Matthias C; Kugel, Harald; Niederstadt, Thomas; Tiemann, Klaus; Schnackenburg, Bernhard; Crelier, Gerard R; Heindel, Walter; Maintz, David

2012-09-01

4D phase contrast flow imaging is increasingly used to study the hemodynamics in various vascular territories and pathologies. The aim of this study was to assess the feasibility and validity of MRI based 4D phase contrast flow imaging for the evaluation of in-stent blood flow in 17 commonly used peripheral stents. 17 different peripheral stents were implanted into a MR compatible flow phantom. In-stent visibility, maximal velocity and flow visualization were assessed and estimates of in-stent patency obtained from 4D phase contrast flow data sets were compared to a conventional 3D contrast-enhanced magnetic resonance angiography (CE-MRA) as well as 2D PC flow measurements. In all but 3 of the tested stents time-resolved 3D particle traces could be visualized inside the stent lumen. Quality of 4D flow visualization and CE-MRA images depended on stent type and stent orientation relative to the magnetic field. Compared to the visible lumen area determined by 3D CE-MRA, estimates of lumen patency derived from 4D flow measurements were significantly higher and less dependent on stent type. A higher number of stents could be assessed for in-stent patency by 4D phase contrast flow imaging (n=14) than by 2D phase contrast flow imaging (n=10). 4D phase contrast flow imaging in peripheral vascular stents is feasible and appears advantageous over conventional 3D contrast-enhanced MR angiography and 2D phase contrast flow imaging. It allows for in-stent flow visualization and flow quantification with varying quality depending on stent type. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Peripheral post-ischemic vascular repair is impaired in a murine model of Alzheimer's disease.

PubMed

Merkulova-Rainon, Tatyana; Mantsounga, Chris S; Broquères-You, Dong; Pinto, Cristina; Vilar, José; Cifuentes, Diana; Bonnin, Philippe; Kubis, Nathalie; Henrion, Daniel; Silvestre, Jean-Sébastien; Lévy, Bernard I

2018-03-07

The pathophysiology of sporadic Alzheimer's disease (AD) remains uncertain. Along with brain amyloid-β (Aβ) deposits and neurofibrillary tangles, cerebrovascular dysfunction is increasingly recognized as fundamental to the pathogenesis of AD. Using an experimental model of limb ischemia in transgenic APPPS1 mice, a model of AD (AD mice), we showed that microvascular impairment also extends to the peripheral vasculature in AD. At D70 following femoral ligation, we evidenced a significant decrease in cutaneous blood flow (- 29%, P < 0.001), collateral recruitment (- 24%, P < 0.001), capillary density (- 22%; P < 0.01) and arteriole density (- 28%; P < 0.05) in hind limbs of AD mice compared to control WT littermates. The reactivity of large arteries was not affected in AD mice, as confirmed by unaltered size, and vasoactive responses to pharmacological stimuli of the femoral artery. We identified blood as the only source of Aβ in the hind limb; thus, circulating Aβ is likely responsible for the impairment of peripheral vasculature repair mechanisms. The levels of the majority of pro-angiogenic mediators were not significantly modified in AD mice compared to WT mice, except for TGF-β1 and PlGF-2, both of which are involved in vessel stabilization and decreased in AD mice (P = 0.025 and 0.019, respectively). Importantly, endothelin-1 levels were significantly increased, while those of nitric oxide were decreased in the hind limb of AD mice (P < 0.05). Our results suggest that vascular dysfunction is a systemic disorder in AD mice. Assessment of peripheral vascular function may therefore provide additional tools for early diagnosis and management of AD.

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. Copyright © 2013 Elsevier Inc. All rights reserved.

Autonomic responses to cold face stimulation in sickle cell disease: a time-varying model analysis.

PubMed

Chalacheva, Patjanaporn; Kato, Roberta M; Sangkatumvong, Suvimol; Detterich, Jon; Bush, Adam; Wood, John C; Meiselman, Herbert; Coates, Thomas D; Khoo, Michael C K

2015-07-14

Sickle cell disease (SCD) is characterized by sudden onset of painful vaso-occlusive crises (VOC), which occur on top of the underlying chronic blood disorder. The mechanisms that trigger VOC remain elusive, but recent work suggests that autonomic dysfunction may be an important predisposing factor. Heart-rate variability has been employed in previous studies, but the derived indices have provided only limited univariate information about autonomic cardiovascular control in SCD. To circumvent this limitation, a time-varying modeling approach was applied to investigate the functional mechanisms relating blood pressure (BP) and respiration to heart rate and peripheral vascular resistance in healthy controls, untreated SCD subjects and SCD subjects undergoing chronic transfusion therapy. Measurements of respiration, heart rate, continuous noninvasive BP and peripheral vascular resistance were made before, during and after the application of cold face stimulation (CFS), which perturbs both the parasympathetic and sympathetic nervous systems. Cardiac baroreflex sensitivity estimated from the model was found to be impaired in nontransfused SCD subjects, but partially restored in SCD subjects undergoing transfusion therapy. Respiratory-cardiac coupling gain was decreased in SCD and remained unchanged by chronic transfusion. These results are consistent with autonomic dysfunction in the form of impaired parasympathetic control and sympathetic overactivity. As well, CFS led to a significant reduction in vascular resistance baroreflex sensitivity in the nontransfused SCD subjects but not in the other groups. This blunting of the baroreflex control of peripheral vascular resistance during elevated sympathetic drive could be a potential factor contributing to the triggering of VOC in SCD. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Role of Interventional Radiology in the Management of Peripheral Vascular Malformations: A Tertiary Care Center Experience.

PubMed

Tahir, Misbah; Mumtaz, Muhammad Anees; Sultan, Anum; Iqbal, Jawaid; Sayani, Raza

2018-03-16

Peripheral vascular malformations (PVMs) represent a wide spectrum of vascular abnormalities occurring due to anomalous connections between arteries, veins, capillaries, and lymphatic channels at the microscopic level, in different combinations. They are rare and challenging to treat. Different operators may have different approaches based on their experience and expertise. Sclerotherapy either alone or in combination with embolization has been used as an independent method for the treatment of PVMs. Purpose The aim of this study is to assess the safety and efficacy of sclerotherapy and embolization, with or without surgery, for the treatment of peripheral vascular malformations, based on our approach. Materials and methods A retrospective review of all patients with PVMs treated in our interventional radiology department from 2011 to 2017 was carried out. Medical records, imaging, and follow-up notes were reviewed to evaluate the response to treatment and post-procedure complications. Results Thirty-four sessions were performed in 15 patients (eight male, seven female) with PVMs. Low-flow lesions were identified in 10, intermediate flow in one, and high flow in four patients. Sodium tetradecyl sulfate (STS) was used as the sclerotherapeutic agent in 10 (66.67%), glue with lipoidal in three (20.0%), and bleomycin in one patient (6.67%). Coils with PVA and a covered stent were used in one and a combination of coil, PVA, and gel foam was used in one patient. A marked response was seen in 11 and a partial response in four patients. One patient developed foot gangrene. Stent thrombosis was noted in one patient with no clinical consequences. Recurrence was seen in two patients, who were lost to follow up. Conclusion PVMs are complex lesions. Sclerotherapy with or without embolization is a safe and effective treatment modality, with clinical response approaching 100%.

The Use of Blood Vessel–Derived Stem Cells for Meniscal Regeneration and Repair

PubMed Central

OSAWA, AKI; HARNER, CHRISTOPHER D.; GHARAIBEH, BURHAN; MATSUMOTO, TOMOYUKI; MIFUNE, YUTAKA; KOPF, SEBASTIAN; INGHAM, SHEILA J. M.; SCHREIBER, VERENA; USAS, ARVYDAS; HUARD, JOHNNY

2015-01-01

Purpose Surgical repairs of tears in the vascular region of the meniscus usually heal better than repairs performed in the avascular region; thus, we hypothesized that this region might possess a richer supply of vascular-derived stem cells than the avascular region. Methods In this study, we analyzed 6 menisci extracted from aborted human fetuses and 12 human lateral menisci extracted from adult human subjects undergoing total knee arthroplasty. Menisci were immunostained for CD34 (a stem cell marker) and CD146 (a pericyte marker) in situ, whereas other menisci were dissected into two regions (peripheral and inner) and used to isolate meniscus-derived cells by flow cytometry. Cell populations expressing CD34 and CD146 were tested for their multi-lineage differentiation potentials, including chondrogenic, osteogenic, and adipogenic lineages. Fetal peripheral meniscus cells were transplanted by intracapsular injection into the knee joints of an athymic rat meniscal tear model. Rat menisci were extracted and histologically evaluated after 4 wk posttransplantation. Results Immunohistochemistry and flow cytometric analyses demonstrated that a higher number of CD34- and CD146-positive cells were found in the peripheral region compared with the inner region. The CD34- and CD146-positive cells isolated from the vascular region of both fetal and adult menisci demonstrated multilineage differentiation capacities and were more potent than cells isolated from the inner (avascular) region. Fetal CD34- and CD146-positive cells transplanted into the athymic rat knee joint were recruited into the meniscal tear sites and contributed to meniscus repair. Conclusions The vascularized region of the meniscus contains more stem cells than the avascular region. These meniscal-derived stem cells were multi-potent and contributed to meniscal regeneration. PMID:23247715

Peripheral Vascular Resistance Impairment during Isometric Physical Exercise in Normotensive Offspring of Hypertensive Parents.

PubMed

Portela, Natália; Amaral, Josária Ferraz; Mira, Pedro Augusto de Carvalho; Souza, Livia Victorino de; Martinez, Daniel Godoy; Laterza, Mateus Camaroti

2017-07-10

A family history of hypertension is associated with vascular and autonomic abnormalities, as well as an impaired neurohemodynamic response to exercise. To test the hypothesis that normotensive individuals with a family history of hypertension present an impaired peripheral vascular resistance response to exercise. The study included 37 normotensive volunteers of both sexes who were sedentary, eutrophic, and nonsmokers, comprising 23 with (FH+; 24 ± 3 years) and 14 without (FH-; 27 ± 5 years) a family history of hypertension. Blood pressure, heart rate (DIXTAL®), forearm blood flow (Hokanson®), and peripheral vascular resistance were simultaneously measured for 3 minutes during rest and, subsequently, for 3 minutes during an isometric exercise at 30% of maximal voluntary contraction (Jamar®). At rest, the FH+ and FH- groups present similar mean blood pressure (83 ± 7 versus 83 ± 5 mmHg, p = 0.96), heart rate (69 ± 8 bpm versus 66 ± 7 bpm, p = 0.18), forearm blood flow (3 ± 1 mL/min/100 mL versus 2.7 ± 1 mL/min/100 mL, p = 0.16), and peripheral vascular resistance (30 ± 9 units versus 34±9 units, p = 0.21), respectively. Both groups showed a significant and similar increase in mean blood pressure (∆ = 15 ± 7 mmHg versus 14 ± 7 mmHg, p = 0.86), heart rate (∆ = 12 ± 8 bpm versus 13 ± 7 bpm, p = 0.86), and forearm blood flow (∆ = 0.8 ± 1.2 mL/min/100 mL versus 1.4 ± 1.1 mL/min/100 mL, p = 0.25), respectively, during exercise. However, individuals in the FH+ group showed no reduction in peripheral vascular resistance during exercise, which was observed in the FH- group (∆ = -0.4 ± 8.6 units versus -7.2 ± 6.3 units, p = 0.03). Normotensive individuals with a family history of hypertension present an impaired peripheral vascular resistance response to exercise. O histórico familiar para hipertensão arterial está relacionado a anormalidades vasculares e autonômicas, bem como disfunções no comportamento neuro-hemodinâmico durante o exercício físico. Testar a hipótese de que indivíduos normotensos com histórico familiar de hipertensão arterial apresentam resposta prejudicada da resistência vascular periférica durante o exercício físico. Foram avaliados 37 normotensos de ambos os sexos, sedentários, eutróficos e não tabagistas, sendo 23 com histórico familiar positivo (HF+, 24 ± 3 anos) e 14 com histórico familiar negativo (HF-, 27 ± 5 anos) para hipertensão arterial. Foram identificados pressão arterial, frequência cardíaca (DIXTAL®), fluxo sanguíneo muscular do antebraço e resistência vascular periférica local (Hokanson®) por 3 minutos durante o repouso e, em seguida, 3 minutos durante exercício isométrico de preensão palmar a 30% da contração voluntária máxima (Jamar®). Em repouso, os grupos HF+ e HF- apresentaram valores semelhantes de pressão arterial média (83 ± 7 mmHg versus 83 ± 5 mmHg, p = 0,96), frequência cardíaca (69 ± 8 bpm versus 66 ± 7 bpm, p = 0,18), fluxo sanguíneo muscular (3 ± 1 mL/min/199 mL versus 2,7 ± 1 mL/min/100 mL, p = 0,16) e resistência vascular periférica (30 ± 9 unidades versus 34 ± 9 unidades, p = 0,21), respectivamente. Durante o exercício, HF+ e HF- mostraram aumento significativo e semelhante da pressão arterial média (∆ = 15 ± 7 mmHg versus 14 ± 7 mmHg, p = 0,86), frequência cardíaca (∆ = 12 ± 8 bpm versus 13 ± 7 bpm, p = 0,86) e fluxo sanguíneo muscular (∆ = 0,8 ± 1,2 mL/min/100 mL versus 1,4 ± 1,1 mL/min/100 mL, p = 0,25), respectivamente. Entretanto, no grupo HF+ não houve redução significativa da resistência vascular periférica durante o exercício, fato que ocorreu no grupo HF- (∆ = -0,4 ± 8,6 unidades versus -7,2 ± 6,3 unidades, p = 0,03). Indivíduos normotensos com histórico familiar de hipertensão arterial apresentam resposta prejudicada da resistência vascular periférica durante o exercício físico.

Registry Assessment of Peripheral Interventional Devices (RAPID): Registry assessment of peripheral interventional devices core data elements.

PubMed

Jones, W Schuyler; Krucoff, Mitchell W; Morales, Pablo; Wilgus, Rebecca W; Heath, Anne H; Williams, Mary F; Tcheng, James E; Marinac-Dabic, J Danica; Malone, Misti L; Reed, Terrie L; Fukaya, Rie; Lookstein, Robert A; Handa, Nobuhiro; Aronow, Herbert D; Bertges, Daniel J; Jaff, Michael R; Tsai, Thomas T; Smale, Joshua A; Zaugg, Margo J; Thatcher, Robert J; Cronenwett, Jack L

2018-02-01

The current state of evaluating patients with peripheral artery disease and more specifically of evaluating medical devices used for peripheral vascular intervention (PVI) remains challenging because of the heterogeneity of the disease process, the multiple physician specialties that perform PVI, the multitude of devices available to treat peripheral artery disease, and the lack of consensus about the best treatment approaches. Because PVI core data elements are not standardized across clinical care, clinical trials, and registries, aggregation of data across different data sources and physician specialties is currently not feasible. Under the auspices of the U.S. Food and Drug Administration's Medical Device Epidemiology Network initiative-and its PASSION (Predictable and Sustainable Implementation of the National Registries) program, in conjunction with other efforts to align clinical data standards-the Registry Assessment of Peripheral Interventional Devices (RAPID) workgroup was convened. RAPID is a collaborative, multidisciplinary effort to develop a consensus lexicon and to promote interoperability across clinical care, clinical trials, and national and international registries of PVI. The current manuscript presents the initial work from RAPID to standardize clinical data elements and definitions, to establish a framework within electronic health records and health information technology procedural reporting systems, and to implement an informatics-based approach to promote the conduct of pragmatic clinical trials and registry efforts in PVI. Ultimately, we hope this work will facilitate and improve device evaluation and surveillance for patients, clinicians, health outcomes researchers, industry, policymakers, and regulators. Copyright © 2017 Society for Vascular Surgery. All rights reserved.

VKORC1 and CYP2C9 Gene Polymorphisms and Warfarin Management

ClinicalTrials.gov

2009-09-02

Atrial Fibrillation; Cardiac Thrombus; Deep Vein Thrombosis; Pulmonary Embolism; Heart Valve Replacement (Mechanical or Biological With AF); Cardiomyopathy (Ischemic or Dilated); Peripheral Vascular Disease

Rationale, scope, and 20-year experience of vascular surgical training with lifelike pulsatile flow models.

PubMed

Eckstein, Hans-Henning; Schmidli, Jürg; Schumacher, Hardy; Gürke, Lorenz; Klemm, Klaus; Duschek, Nikolaus; Meile, Toni; Assadian, Afshin

2013-05-01

Vascular surgical training currently has to cope with various challenges, including restrictions on work hours, significant reduction of open surgical training cases in many countries, an increasing diversity of open and endovascular procedures, and distinct expectations by trainees. Even more important, patients and the public no longer accept a "learning by doing" training philosophy that leaves the learning curve on the patient's side. The Vascular International (VI) Foundation and School aims to overcome these obstacles by training conventional vascular and endovascular techniques before they are applied on patients. To achieve largely realistic training conditions, lifelike pulsatile models with exchangeable synthetic arterial inlays were created to practice carotid endarterectomy and patch plasty, open abdominal aortic aneurysm surgery, and peripheral bypass surgery, as well as for endovascular procedures, including endovascular aneurysm repair, thoracic endovascular aortic repair, peripheral balloon dilatation, and stenting. All models are equipped with a small pressure pump inside to create pulsatile flow conditions with variable peak pressures of ~90 mm Hg. The VI course schedule consists of a series of 2-hour modules teaching different open or endovascular procedures step-by-step in a standardized fashion. Trainees practice in pairs with continuous supervision and intensive advice provided by highly experienced vascular surgical trainers (trainer-to-trainee ratio is 1:4). Several evaluations of these courses show that tutor-assisted training on lifelike models in an educational-centered and motivated environment is associated with a significant increase of general and specific vascular surgical technical competence within a short period of time. Future studies should evaluate whether these benefits positively influence the future learning curve of vascular surgical trainees and clarify to what extent sophisticated models are useful to assess the level of technical skills of vascular surgical residents at national or international board examinations. This article gives an overview of our experiences of >20 years of practical training of beginners and advanced vascular surgeons using lifelike pulsatile vascular surgical training models. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Influence of a Multi-parametric Optimization Strategy for General Anesthesia on Postoperative Morbidity and Mortality

ClinicalTrials.gov

2017-11-20

Coronary; Ischemic; Arrhythmias, Cardiac; Heart Failure; Peripheral Vascular Diseases; Dementia; Stroke; Pulmonary Disease, Chronic Obstructive; Respiratory Insufficiency; Alcoholism; Cancer; Diabetes; Renal Insufficiency

Peripherally inserted central catheter - insertion

MedlinePlus

... ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 26. Smith SF, Duell DJ, Martin BC, Gonzalez L, Aebersold M. Central vascular access devices. In: Smith SF, Duell DJ, Martin BC, Gonzalez L, Aebersold ...

Atrial Fibrillation Medications

MedlinePlus

... for Heart.org Arrhythmia About Arrhythmia Why Arrhythmia Matters Understand Your Risk for Arrhythmia Symptoms, Diagnosis & Monitoring ... How HBP Harms Your Health Make Changes That Matter Find HBP Tools & Resources Stroke Vascular Health Peripheral ...

Mechanisms of peripheral immune-cell-mediated analgesia in inflammation: clinical and therapeutic implications.

PubMed

Hua, Susan; Cabot, Peter J

2010-09-01

Peripheral mechanisms of endogenous pain control are significant. In peripheral inflamed tissue, an interaction between immune-cell-derived opioids and opioid receptors localized on sensory nerve terminals results in potent, clinically measurable analgesia. Opioid peptides and the mRNA encoding their precursor proteins are present in immune cells. These cells 'home' preferentially to injured tissue, where they secrete opioids to reduce pain. Investigation of the mechanisms underlying the migration of opioid-containing immune cells to inflamed tissue is an active area of research, with recent data demonstrating the importance of cell adhesion molecules in leukocyte adhesion to both the endothelium in vascular transmigration and to neurons within peripheral inflamed tissue. This review summarizes the physiological mechanisms and clinical significance of this unique endogenous peripheral analgesic pathway and discusses therapeutic implications for the development of novel targeted peripheral analgesics. Copyright 2010 Elsevier Ltd. All rights reserved.

Imaging Stem Cell Therapy for the Treatment of Peripheral Arterial Disease

PubMed Central

Ransohoff, Julia D.; Wu, Joseph C.

2013-01-01

Arteriosclerotic cardiovascular diseases are among the leading causes of morbidity and mortality worldwide. Therapeutic angiogenesis aims to treat ischemic myocardial and peripheral tissues by delivery of recombinant proteins, genes, or cells to promote neoangiogenesis. Concerns regarding the safety, side effects, and efficacy of protein and gene transfer studies have led to the development of cell-based therapies as alternative approaches to induce vascular regeneration and to improve function of damaged tissue. Cell-based therapies may be improved by the application of imaging technologies that allow investigators to track the location, engraftment, and survival of the administered cell population. The past decade of investigations has produced promising clinical data regarding cell therapy, but design of trials and evaluation of treatments stand to be improved by emerging insight from imaging studies. Here, we provide an overview of pre-clinical and clinical experience using cell-based therapies to promote vascular regeneration in the treatment of peripheral arterial disease. We also review four major imaging modalities and underscore the importance of in vivo analysis of cell fate for a full understanding of functional outcomes. PMID:22239638

Peripheral artery bypass - leg

MedlinePlus

... nih.gov/pubmed/23473760 . Society for Vascular Surgery Lower Extremity Guidelines Writing Group; Conte MS, Pomposelli FB, et ... practice guidelines for atherosclerotic occlusive disease of the ... management of asymptomatic disease and claudication. J Vasc ...

Vascular biology: cellular and molecular profiling.

PubMed

Baird, Alison E; Wright, Violet L

2006-02-01

Our understanding of the mechanisms underlying cerebrovascular atherosclerosis has improved in recent years, but significant gaps remain. New insights into the vascular biological processes that result in ischemic stroke may come from cellular and molecular profiling studies of the peripheral blood. In recent cellular profiling studies, increased levels of a proinflammatory T-cell subset (CD4 (+)CD28 (-)) have been associated with stroke recurrence and death. Expansion of this T-cell subset may occur after ischemic stroke and be a pathogenic mechanism leading to recurrent stroke and death. Increases in certain phenotypes of endothelial cell microparticles have been found in stroke patients relative to controls, possibly indicating a state of increased vascular risk. Molecular profiling approaches include gene expression profiling and proteomic methods that permit large-scale analyses of the transcriptome and the proteome, respectively. Ultimately panels of genes and proteins may be identified that are predictive of stroke risk. Cellular and molecular profiling studies of the peripheral blood and of atherosclerotic plaques may also pave the way for the development of therapeutic agents for primary and secondary stroke prevention.

Calcium antagonism: aldosterone and vascular responses to catecholamines and angiotensin II in man.

PubMed

Elliott, H L

1993-12-01

Effects of calcium antagonists on pressor mechanisms: A number of differences have been reported in the variable extent to which calcium antagonists interfere with various pressor mechanisms. In theory, high lipid solubility, membrane-binding characteristics and a prolonged duration of action appear to be requirements for a calcium antagonist to affect mechanisms such as vasodilation, endogenous vasoconstrictor responses, hormone release and natriuretic activity. Reduction in peripheral vascular resistance: A reduction in peripheral vascular resistance is fundamental to the antihypertensive effect not only of calcium antagonists but also of angiotensin converting enzyme inhibitors and alpha 1-adrenoceptor antagonists. However, only the calcium antagonists interfere directly with the pressor responses mediated by both the adrenergic nervous system and the renin-angiotensin system. Mechanism of lacidipine effects: Preliminary results with the new dihydropyridine calcium antagonist lacidipine indicate that it not only has vasodilator activity but that it also interferes with both adrenergic and non-adrenergic endogenous vasoconstrictor mechanisms. This may provide additional potentially beneficial cardiovascular effects, particularly in relation to left ventricular hypertrophy and dysfunction.

Summary of Research Adaptions of Visceral and Cerebral Resistance Arteries to Simulated Microgravity

NASA Technical Reports Server (NTRS)

Delp, Michael

2003-01-01

The proposed studies were designed address the effects of simulated microgravity on vascular smooth muscle and endothelial cell function in resistance arteries isolated from visceral tissues (spleen, mesentery and kidneys) and cerebrum. Alterations in vascular function induced by microgravity are particularly relevant to the problems of orthostatic intolerance and reduced exercise capacity experienced by astronauts upon re-entry into the earth's gravitational field. Decrements in contractile function or enhanced vasodilatory responsiveness of peripheral resistance arteries could lead to decreased peripheral resistance and orthostatic hypotension. Alternatively, augmentation of contractile function in cerebral resistance arteries could lead to increased cerebral vascular resistance and diminished perfusion of the brain. The Specific Aims and hypotheses were proposed in this grant. Following each of the Specific Aims, progress toward addressing that specific aim is presented. With the exception of Specific Aim VI (see aim for details), all aims have been experimentally addressed as proposed. The final six months of the granting period will be used for manuscript preparation; manuscripts in preparation will contain results from Specific Aims I-IV. Results from Specific Aims V and VI have been published.

MRI for peripheral artery disease: Introductory physics for vascular physicians.

PubMed

Roy, Trisha L; Forbes, Thomas L; Dueck, Andrew D; Wright, Graham A

2018-04-01

Magnetic resonance imaging (MRI) has advanced significantly in the past decade and provides a safe and non-invasive method of evaluating peripheral artery disease (PAD), with and without using exogenous contrast agents. MRI offers a promising alternative for imaging patients but the complexity of MRI can make it less accessible for physicians to understand or use. This article provides a brief introduction to the technical principles of MRI for physicians who manage PAD patients. We discuss the basic principles of how MRI works and tailor the discussion to how MRI can evaluate anatomic characteristics of peripheral arterial lesions.

Ginkgo biloba Extract in Vascular Protection: Molecular Mechanisms and Clinical Applications.

PubMed

Tian, Jinfan; Liu, Yue; Chen, Keji

2017-01-01

Leaves of Ginkgo biloba, a "living fossil," have been used as traditional herbal medicine for hundreds of years in China. Currently, its application in vascular protection is garnering much attention. In this manuscript, preclinical studies were reviewed to discuss various mechanisms underlying the vascular protection by Ginkgo biloba extract (GBE). Additionally, we reviewed clinical studies to present the application of GBE in the ischaemic disease. GBE, a commonly used dietary supplement, has been shown to act as an antioxidant and freeradical scavenger, a membrane stabilizer, an inhibitor of the platelet-activating factor, a vasodilator, and a regulator of metabolism. Currently, there exist a growing number of clinical studies about GBE in the application of cardiovascular disease, peripheral vascular disease (PVD) and diabetic vascular complications. GBE, a promising therapeutic agent for cardiovascular and ischaemic diseases, exerts vascular- protection function by a comprehensive mechanisms. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Rolling the Human Amnion to Engineer Laminated Vascular Tissues

PubMed Central

Amensag, Salma

2012-01-01

The prevalence of cardiovascular disease and the limited availability of suitable autologous transplant vessels for coronary and peripheral bypass surgeries is a significant clinical problem. A great deal of progress has been made over recent years to develop biodegradable materials with the potential to remodel and regenerate vascular tissues. However, the creation of functional biological scaffolds capable of withstanding vascular stress within a clinically relevant time frame has proved to be a challenging proposition. As an alternative approach, we report the use of a multilaminate rolling approach using the human amnion to generate a tubular construct for blood vessel regeneration. The human amniotic membrane was decellularized by agitation in 0.03% (w/v) sodium dodecyl sulfate to generate an immune compliant material. The adhesion of human umbilical vein endothelial cells (EC) and human vascular smooth muscle cells (SMC) was assessed to determine initial binding and biocompatibility (monocultures). Extended cultures were either assessed as flat membranes, or rolled to form concentric multilayered conduits. Results showed positive EC adhesion and a progressive repopulation by SMC. Functional changes in SMC gene expression and the constructs' bulk mechanical properties were concomitant with vessel remodeling as assessed over a 40-day culture period. A significant advantage with this approach is the ability to rapidly produce a cell-dense construct with an extracellular matrix similar in architecture and composition to natural vessels. The capacity to control physical parameters such as vessel diameter, wall thickness, shape, and length are critical to match vessel compliance and tailor vessel specifications to distinct anatomical locations. As such, this approach opens new avenues in a range of tissue regenerative applications that may have a much wider clinical impact. PMID:22616610

Vascular corrosion casting of normal and pre-eclamptic placentas.

PubMed

Yin, Geping; Chen, Ming; Li, Juan; Zhao, Xiaoli; Yang, Shujun; Li, Xiuyun; Yuan, Zheng; Wu, Aifang

2017-12-01

Pre-eclampsia is an important cause of maternal and fetal morbidity and mortality that is associated with decreased placental perfusion. In the present study, vascular corrosion casting was used to investigate the differences in structural changes of the fetoplacental vasculature between normal and pre-eclamptic placentas. An improved epoxy resin vascular casting technique was used in the present study. Casting media were infused into 40 normal and 40 pre-eclamptic placentas through umbilical arteries and veins in order to construct three dimensional fetoplacental vasculatures. The number of branches, diameter, morphology and peripheral artery-to-vein ratio were measured for each specimen. The results indicated that the venous system of normal placentas was divided into 5-7 grades of branches and the volume of the vascular bed was 155.5±45.3 ml. In severe pre-eclamptic placentas, the volume was 106.4±36.1 ml, which was significantly lower compared with normal placentas (P<0.01). The venous system of pre-eclamptic placentas was divided into 4-5 grades of branches, which was much more sparse compared with normal placentas. In additions, the diameters of grade 1-3 veins and grade 2-3 arteries were significantly smaller in severe pre-eclampsia (P<0.05). In conclusion, pre-eclamptic placentas displayed a decreased volume of vascular bed, smaller diameters of grade 1-3 veins and grade 2-3 arteries, and an increased peripheral artery-to-vein ratio, which may be a cause of the placental dysfunction during severe pre-eclampsia.

Attenuated flow‐induced dilatation of middle cerebral arteries is related to increased vascular oxidative stress in rats on a short‐term high salt diet

PubMed Central

Cosic, Anita; Jukic, Ivana; Stupin, Ana; Mihalj, Martina; Mihaljevic, Zrinka; Novak, Sanja; Vukovic, Rosemary

2016-01-01

Key points Recent studies have shown that high salt (HS) intake leads to endothelial dysfunction and impaired vascular reactivity in different vascular beds in both animal and human models, due to increased oxidative stress.The objective of this study was to assess vascular response to flow‐induced dilatation (FID) and to elucidate the role of vascular oxidative stress/antioxidative capacity in middle cerebral arteries (MCAs) of HS‐fed rats in vitro.The novelty of this study is in demonstrating impaired flow‐induced dilatation of MCAs and down‐regulation of vascular antioxidant genes with HS intake, leading to increased levels of oxidative stress in blood vessels and peripheral lymph organs, which together contribute to impaired FID.In addition, results show increased oxidative stress in leukocytes of peripheral lymph organs, suggesting the occurrence of inflammatory processes due to HS intake.Recirculation of leukocytes might additionally increase vascular oxidative stress in vivo. Abstract The aim of this study was to determine flow‐induced dilatation (FID) and the role of oxidative stress/antioxidative capacity in isolated, pressurized middle cerebral arteries (MCAs) of high salt (HS)‐fed rats. Healthy male Sprague‐Dawley rats (11 weeks old) were fed low salt (0.4% NaCl; LS group) or high salt (4% NaCl; HS group) diets for 1 week. Reactivity of MCAs in response to stepwise increases in pressure gradient (Δ10–Δ100 mmHg) was determined in the absence or presence of the superoxide dismutase (SOD) mimetic TEMPOL and/or the nitric oxide synthases (NOS) inhibitor N ω‐nitro‐l‐arginine methyl ester (l‐name). mRNA levels of antioxidative enzymes, NAPDH‐oxidase components, inducible (iNOS) and endothelial nitric oxide synthases (eNOS) were determined by quantitative real‐time PCR. Blood pressure (BP), antioxidant enzymes activity, oxidative stress in peripheral leukocytes, lipid peroxidation products and the antioxidant capacity of plasma were measured for both groups. FID was reduced in the HS group compared to the LS group. The presence of TEMPOL restored dilatation in the HS group, with no effect in the LS group. Expression of glutathione peroxidase 4 (GPx4) and iNOS in the HS group was significantly decreased; oxidative stress was significantly higher in the HS group compared to the LS group. HS intake significantly induced basal reactive oxygen species production in the leukocytes of mesenteric lymph nodes and splenocytes, and intracellular production after stimulation in peripheral lymph nodes. Antioxidant enzyme activity and BP were not affected by HS diet. Low GPx4 expression, increased superoxide production in leukocytes, and decreased iNOS expression are likely to underlie increased oxidative stress and reduced nitric oxide bioavailability, leading to impairment of FID in the HS group without changes in BP values. PMID:27061200

Attenuated flow-induced dilatation of middle cerebral arteries is related to increased vascular oxidative stress in rats on a short-term high salt diet.

PubMed

Cosic, Anita; Jukic, Ivana; Stupin, Ana; Mihalj, Martina; Mihaljevic, Zrinka; Novak, Sanja; Vukovic, Rosemary; Drenjancevic, Ines

2016-09-01

Recent studies have shown that high salt (HS) intake leads to endothelial dysfunction and impaired vascular reactivity in different vascular beds in both animal and human models, due to increased oxidative stress. The objective of this study was to assess vascular response to flow-induced dilatation (FID) and to elucidate the role of vascular oxidative stress/antioxidative capacity in middle cerebral arteries (MCAs) of HS-fed rats in vitro. The novelty of this study is in demonstrating impaired flow-induced dilatation of MCAs and down-regulation of vascular antioxidant genes with HS intake, leading to increased levels of oxidative stress in blood vessels and peripheral lymph organs, which together contribute to impaired FID. In addition, results show increased oxidative stress in leukocytes of peripheral lymph organs, suggesting the occurrence of inflammatory processes due to HS intake. Recirculation of leukocytes might additionally increase vascular oxidative stress in vivo. The aim of this study was to determine flow-induced dilatation (FID) and the role of oxidative stress/antioxidative capacity in isolated, pressurized middle cerebral arteries (MCAs) of high salt (HS)-fed rats. Healthy male Sprague-Dawley rats (11 weeks old) were fed low salt (0.4% NaCl; LS group) or high salt (4% NaCl; HS group) diets for 1 week. Reactivity of MCAs in response to stepwise increases in pressure gradient (Δ10-Δ100 mmHg) was determined in the absence or presence of the superoxide dismutase (SOD) mimetic TEMPOL and/or the nitric oxide synthases (NOS) inhibitor N(ω) -nitro-l-arginine methyl ester (l-NAME). mRNA levels of antioxidative enzymes, NAPDH-oxidase components, inducible (iNOS) and endothelial nitric oxide synthases (eNOS) were determined by quantitative real-time PCR. Blood pressure (BP), antioxidant enzymes activity, oxidative stress in peripheral leukocytes, lipid peroxidation products and the antioxidant capacity of plasma were measured for both groups. FID was reduced in the HS group compared to the LS group. The presence of TEMPOL restored dilatation in the HS group, with no effect in the LS group. Expression of glutathione peroxidase 4 (GPx4) and iNOS in the HS group was significantly decreased; oxidative stress was significantly higher in the HS group compared to the LS group. HS intake significantly induced basal reactive oxygen species production in the leukocytes of mesenteric lymph nodes and splenocytes, and intracellular production after stimulation in peripheral lymph nodes. Antioxidant enzyme activity and BP were not affected by HS diet. Low GPx4 expression, increased superoxide production in leukocytes, and decreased iNOS expression are likely to underlie increased oxidative stress and reduced nitric oxide bioavailability, leading to impairment of FID in the HS group without changes in BP values. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Patient's Guide to Taking Warfarin

MedlinePlus

... for Heart.org Arrhythmia About Arrhythmia Why Arrhythmia Matters Understand Your Risk for Arrhythmia Symptoms, Diagnosis & Monitoring ... How HBP Harms Your Health Make Changes That Matter Find HBP Tools & Resources Stroke Vascular Health Peripheral ...

Heart Attack Symptoms in Women

MedlinePlus

... for Heart.org Arrhythmia About Arrhythmia Why Arrhythmia Matters Understand Your Risk for Arrhythmia Symptoms, Diagnosis & Monitoring ... How HBP Harms Your Health Make Changes That Matter Find HBP Tools & Resources Stroke Vascular Health Peripheral ...

Single Photon Emission Computed Tomography (SPECT)

MedlinePlus

... for Heart.org Arrhythmia About Arrhythmia Why Arrhythmia Matters Understand Your Risk for Arrhythmia Symptoms, Diagnosis & Monitoring ... How HBP Harms Your Health Make Changes That Matter Find HBP Tools & Resources Stroke Vascular Health Peripheral ...

Endovascular balloon-assisted embolization of high-flow peripheral vascular lesions using dual-lumen coaxial balloon microcatheter and Onyx: initial experience.

PubMed

Jagadeesan, Bharathi D; Mortazavi, Shabnam; Hunter, David W; Duran-Castro, Olga L; Snyder, Gregory B; Siedel, Glen F; Golzarian, Jafar

2014-04-01

Balloon-assisted embolization performed by delivering Onyx ethylene vinyl alcohol copolymer through a dual-lumen coaxial balloon microcatheter is a new technique for the management of peripheral vascular lesions. This technique does not require an initial reflux of Onyx to form around the tip of the microcatheter before antegrade flow of Onyx can commence. In a series of four patients who were treated with the use of this technique, the absence of significant reflux of Onyx was noted, as were excellent navigability and easy retrieval of the balloon microcatheter. However, in one patient, there was inadvertent adverse embolization of a digital artery, which was not caused by reflux of Onyx but could still be related to balloon inflation. © 2013 SIR Published by SIR All rights reserved.

Applications of Doppler ultrasound in clinical vascular disease

NASA Technical Reports Server (NTRS)

Barnes, R. W.; Hokanson, D. E.; Sumner, D. S.; Strandness, D. E., Jr.

1975-01-01

Doppler ultrasound has become the most useful and versatile noninvasive technique for objective evaluation of clinical vascular disease. Commercially available continuous-wave instruments provide qualitative and quantitative assessment of venous and arterial disease. Pulsed Doppler ultrasound was developed to provide longitudinal and transverse cross-sectional images of the arterial lumen with a resolution approaching that of conventional X-ray techniques. Application of Doppler ultrasound in venous, peripheral arterial, and cerebrovascular diseases is reviewed.

Changes in Central Aortic Pressure Levels, Wave Components and Determinants Associated with High Peripheral Blood Pressure States in Childhood: Analysis of Hypertensive Phenotype.

PubMed

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

2016-10-01

The aims were to determine whether children's high peripheral blood pressure states (HBP) are associated with increased central aortic blood pressure (BP) and to characterize hemodynamic and vascular changes associated with HBP in terms of 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 amplitude. We included 154 subjects (mean age 11; range 4-16 years) assigned to one of two groups: normal peripheral BP (NBP, n = 101), defined as systolic and diastolic BP < 90th percentile, or high BP (HBP, n = 53), defined as average systolic and/or diastolic BP levels ≥90th percentile (curves for sex, age and body height). The HBP group included children with hypertensive and pre-hypertensive BP levels. After a first analysis, groups were compared excluding obese and dyslipidemic children. Peripheral and central aortic BP, PWV and pulse wave-derived parameters (augmentation index, forward and backward wave components' amplitude) were measured using gold-standard techniques, applanation tonometry (SphygmoCor) and oscillometry (Mobil-O-Graph). Independent of the presence of dyslipidemia and/or obesity, aortic systolic and pulse BP were higher in HBP than in NBP children. The increase in central BP could not be explained by an increase in the relative contribution of reflections to the aortic pressure wave, higher PVR or by an augmented peripheral reflection coefficient. Instead, the rise in central BP would be explained by an increase in the amplitude of both incident and reflected wave components.

Lower Limb Arteriovenous Communications in Diabetes Mellitus: A Potential Reason for Aggravation of Ischemic Symptoms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamady, Mohamad S.; Yu, Dominic F.; Sayer, Gabriel L.

2006-10-15

The aim of this study was to assess the prevalence and to evaluate the clinical associations of arteriovenous communications in patients with diabetes mellitus (DM) and lower limb peripheral arterial ischemia. Peripheral arteriography of DM patients from an eight-year period (1993-2000) was evaluated retrospectively by two observers. The presence of arteriovenous communications, defined as occurring without evidence of a preceding precipitating event, and the distribution and severity of the vascular disease were evaluated. The type (non-insulin-dependent DM or insulin-dependent DM) and the duration of the DM, the presenting symptoms, and the presence of a peripheral neuropathy were documented by amore » review of the clinical records. A total of 348 arteriography studies in 285 DM patients were evaluated (duration of DM: median, 16 years; range, 7-42 years); an arteriovenous communication was present in 14/285 patients (4.9%), 9 male and 5 female (median age, 71 years; range, 17-84 years). Symptoms were those of a peripheral leg ulcer (n = 11), claudication (n = 3), and gangrene (n = 1), with symptoms ipsilateral to the side of the arteriovenous communication in 13/14 patients. The sites of the arteriovenous communications were infra popliteal (n = 7), popliteal (n = 3), superficial femoral artery (n = 3), and common femoral artery (n = 1). Features of a peripheral neuropathy were found in 12/14 and ipsilateral to the side of the communication in 11/12. Arteriovenous communications in the peripheral femoral arterial system of patients with DM is an uncommon finding. Although not proven in the current study, arteriovenous communications might be associated with more severe symptoms than that attributable to the underlying vascular disease alone.« less

Composite pheochromocytoma with a malignant peripheral nerve sheath tumor: Case report and review of the literature.

PubMed

Namekawa, Takeshi; Utsumi, Takanobu; Imamoto, Takashi; Kawamura, Koji; Oide, Takashi; Tanaka, Tomoaki; Nihei, Naoki; Suzuki, Hiroyoshi; Nakatani, Yukio; Ichikawa, Tomohiko

2016-07-01

Adrenal tumors with more than one cellular component are uncommon. Furthermore, an adrenal tumor composed of a pheochromocytoma and a malignant peripheral nerve sheath tumor is extremely rare. A composite pheochromocytoma with malignant peripheral nerve sheath tumor in a 42-year-old man is reported here. After adequate preoperative control, left adrenalectomy was performed simultaneously with resection of the ipsilateral kidney for spontaneous rupture of the left adrenal tumor. Pathological findings demonstrated pheochromocytoma and malignant peripheral nerve sheath tumor in a ruptured adrenal tumor. To date, there have been only four reported cases of composite pheochromocytoma with malignant peripheral nerve sheath tumor, so the present case is only the fifth case in the world. Despite the very poor prognosis of patients with pheochromocytoma and malignant peripheral nerve sheath tumors reported in the literature, the patient remains well without evidence of recurrence or new metastatic lesions at 36 months postoperatively. Copyright © 2012. Published by Elsevier Taiwan.

Cambial variations of Piper (Piperaceae) in Taiwan.

PubMed

Yang, Sheng-Zehn; Chen, Po-Hao

2017-12-01

Cambial variations in lianas of Piperaceae in Taiwan have not been studied previously. The stem anatomy of seven Piper species from Taiwan was examined to document cambial variations and better distinguish the species when leaves are absent. A key for the seven species is provided, based on the internal stem anatomy. The seven Piper species climb via adventitious roots, and in cross section, the stems were generally eccentric and oblate, although a transversely elliptic stem was found in P. kadsura (Choisy) Ohwi and P. sintenense Hatus. A cambial variant with secondary growth of external primary vascular bundles and xylem in plates was observed in all species except Piper betle L., which developed another cambium variant with xylem furrowed deeply by parenchyma proliferation. The sclerenchymatous ring surrounding the medullary vascular bundles was always continuous except in P. betle, where it was discontinuous. Mucilage canals varied from absent to present in the center of the pith, or present in the pith and inner cortex. Different sizes of vessels dispersed throughout the stem were ring or diffuse porous. The numbers of medullary and peripheral vascular bundles were distinctive and the widths of rays were noticeably different in each species. Differences in the growth rate of the medullary vascular bundles produced two development types of vascular bundles, although in both types, the peripheral vascular bundles gradually lengthen and become separated from each other by wide rays. We documented the internal stem anatomy of six previously unstudied species of Piper, including three endemic species, P. kwashoense Hayata, P. sintenense, and P. taiwanense Lin and Lu, and found that P. betle had deeply furrowed xylem, which had not been reported for the species before. The descriptions and photographs of seven Piper species will also provide a basis for further morphological studies.

Intravital Imaging of Vascular Transmigration by the Lyme Spirochete: Requirement for the Integrin Binding Residues of the B. burgdorferi P66 Protein.

PubMed

Kumar, Devender; Ristow, Laura C; Shi, Meiqing; Mukherjee, Priyanka; Caine, Jennifer A; Lee, Woo-Yong; Kubes, Paul; Coburn, Jenifer; Chaconas, George

2015-12-01

Vascular extravasation, a key step in systemic infection by hematogenous microbial pathogens, is poorly understood, but has been postulated to encompass features similar to vascular transmigration by leukocytes. The Lyme disease spirochete can cause a variety of clinical manifestations, including arthritis, upon hematogenous dissemination. This pathogen encodes numerous surface adhesive proteins (adhesins) that may promote extravasation, but none have yet been implicated in this process. In this work we report the novel use of intravital microscopy of the peripheral knee vasculature to study transmigration of the Lyme spirochete in living Cd1d-/-mice. In the absence of iNKT cells, major immune modulators in the mouse joint, spirochetes that have extravasated into joint-proximal tissue remain in the local milieu and can be enumerated accurately. We show that BBK32, a fibronectin and glycosaminoglycan adhesin of B. burgdorferi involved in early steps of endothelial adhesion, is not required for extravasation from the peripheral knee vasculature. In contrast, almost no transmigration occurs in the absence of P66, an outer membrane protein that has porin and integrin adhesin functions. Importantly, P66 mutants specifically defective in integrin binding were incapable of promoting extravasation. P66 itself does not promote detectable microvascular interactions, suggesting that vascular adhesion of B. burgdorferi mediated by other adhesins, sets the stage for P66-integrin interactions leading to transmigration. Although integrin-binding proteins with diverse functions are encoded by a variety of bacterial pathogens, P66 is the first to have a documented and direct role in vascular transmigration. The emerging picture of vascular escape by the Lyme spirochete shows similarities, but distinct differences from leukocyte transmigration.

Magnetic resonance imaging-based computational modelling of blood flow and nanomedicine deposition in patients with peripheral arterial disease

PubMed Central

Hossain, Shaolie S.; Zhang, Yongjie; Fu, Xiaoyi; Brunner, Gerd; Singh, Jaykrishna; Hughes, Thomas J. R.; Shah, Dipan; Decuzzi, Paolo

2015-01-01

Peripheral arterial disease (PAD) is generally attributed to the progressive vascular accumulation of lipoproteins and circulating monocytes in the vessel walls leading to the formation of atherosclerotic plaques. This is known to be regulated by the local vascular geometry, haemodynamics and biophysical conditions. Here, an isogeometric analysis framework is proposed to analyse the blood flow and vascular deposition of circulating nanoparticles (NPs) into the superficial femoral artery (SFA) of a PAD patient. The local geometry of the blood vessel and the haemodynamic conditions are derived from magnetic resonance imaging (MRI), performed at baseline and at 24 months post intervention. A dramatic improvement in blood flow dynamics is observed post intervention. A 500% increase in peak flow rate is measured in vivo as a consequence of luminal enlargement. Furthermore, blood flow simulations reveal a 32% drop in the mean oscillatory shear index, indicating reduced disturbed flow post intervention. The same patient information (vascular geometry and blood flow) is used to predict in silico in a simulation of the vascular deposition of systemically injected nanomedicines. NPs, targeted to inflammatory vascular molecules including VCAM-1, E-selectin and ICAM-1, are predicted to preferentially accumulate near the stenosis in the baseline configuration, with VCAM-1 providing the highest accumulation (approx. 1.33 and 1.50 times higher concentration than that of ICAM-1 and E-selectin, respectively). Such selective deposition of NPs within the stenosis could be effectively used for the detection and treatment of plaques forming in the SFA. The presented MRI-based computational protocol can be used to analyse data from clinical trials to explore possible correlations between haemodynamics and disease progression in PAD patients, and potentially predict disease occurrence as well as the outcome of an intervention. PMID:25878124

Intravital Imaging of Vascular Transmigration by the Lyme Spirochete: Requirement for the Integrin Binding Residues of the B. burgdorferi P66 Protein

PubMed Central

Kumar, Devender; Ristow, Laura C.; Shi, Meiqing; Mukherjee, Priyanka; Caine, Jennifer A.; Lee, Woo-Yong; Kubes, Paul; Coburn, Jenifer; Chaconas, George

2015-01-01

Vascular extravasation, a key step in systemic infection by hematogenous microbial pathogens, is poorly understood, but has been postulated to encompass features similar to vascular transmigration by leukocytes. The Lyme disease spirochete can cause a variety of clinical manifestations, including arthritis, upon hematogenous dissemination. This pathogen encodes numerous surface adhesive proteins (adhesins) that may promote extravasation, but none have yet been implicated in this process. In this work we report the novel use of intravital microscopy of the peripheral knee vasculature to study transmigration of the Lyme spirochete in living Cd1d -/-mice. In the absence of iNKT cells, major immune modulators in the mouse joint, spirochetes that have extravasated into joint-proximal tissue remain in the local milieu and can be enumerated accurately. We show that BBK32, a fibronectin and glycosaminoglycan adhesin of B. burgdorferi involved in early steps of endothelial adhesion, is not required for extravasation from the peripheral knee vasculature. In contrast, almost no transmigration occurs in the absence of P66, an outer membrane protein that has porin and integrin adhesin functions. Importantly, P66 mutants specifically defective in integrin binding were incapable of promoting extravasation. P66 itself does not promote detectable microvascular interactions, suggesting that vascular adhesion of B. burgdorferi mediated by other adhesins, sets the stage for P66-integrin interactions leading to transmigration. Although integrin-binding proteins with diverse functions are encoded by a variety of bacterial pathogens, P66 is the first to have a documented and direct role in vascular transmigration. The emerging picture of vascular escape by the Lyme spirochete shows similarities, but distinct differences from leukocyte transmigration. PMID:26684456

Longitudinal Assessment of Vascular Function With Sunitinib in Patients With Metastatic Renal Cell Carcinoma.

PubMed

Catino, Anna B; Hubbard, Rebecca A; Chirinos, Julio A; Townsend, Ray; Keefe, Stephen; Haas, Naomi B; Puzanov, Igor; Fang, James C; Agarwal, Neeraj; Hyman, David; Smith, Amanda M; Gordon, Mary; Plappert, Theodore; Englefield, Virginia; Narayan, Vivek; Ewer, Steven; ElAmm, Chantal; Lenihan, Daniel; Ky, Bonnie

2018-03-01

Sunitinib, used widely in metastatic renal cell carcinoma, can result in hypertension, left ventricular dysfunction, and heart failure. However, the relationships between vascular function and cardiac dysfunction with sunitinib are poorly understood. In a multicenter prospective study of 84 metastatic renal cell carcinoma patients, echocardiography, arterial tonometry, and BNP (B-type natriuretic peptide) measures were performed at baseline and at 3.5, 15, and 33 weeks after sunitinib initiation, correlating with sunitinib cycles 1, 3, and 6. Mean change in vascular function parameters and 95% confidence intervals were calculated. Linear regression models were used to estimate associations between vascular function and left ventricular ejection fraction, longitudinal strain, diastolic function (E/e'), and BNP. After 3.5 weeks of sunitinib, mean systolic blood pressure increased by 9.5 mm Hg (95% confidence interval, 2.0-17.1; P =0.02) and diastolic blood pressure by 7.2 mm Hg (95% confidence interval, 4.3-10.0; P <0.001) across all participants. Sunitinib resulted in increases in large artery stiffness (carotid-femoral pulse wave velocity) and resistive load (total peripheral resistance and arterial elastance; all P <0.05) and changes in pulsatile load (total arterial compliance and wave reflection). There were no statistically significant associations between vascular function and systolic dysfunction (left ventricular ejection fraction and longitudinal strain). However, baseline total peripheral resistance, arterial elastance, and aortic impedance were associated with worsening diastolic function and filling pressures over time. In patients with metastatic renal cell carcinoma, sunitinib resulted in early, significant increases in blood pressure, arterial stiffness, and resistive and pulsatile load within 3.5 weeks of treatment. Baseline vascular function parameters were associated with worsening diastolic but not systolic function. © 2018 American Heart Association, Inc.

Comparative effectiveness of peripheral vascular intervention versus surgical bypass for critical limb ischemia in the Vascular Study Group of Greater New York.

PubMed

Meltzer, Andrew J; Sedrakyan, Art; Isaacs, Abby; Connolly, Peter H; Schneider, Darren B

2016-11-01

In this study, the effectiveness of peripheral vascular intervention (PVI) was compared with surgical bypass grafting (BPG) for critical limb ischemia (CLI) in the Vascular Study Group of Greater New York (VSGGNY). Patients undergoing BPG or PVI for CLI at VSGGNY centers (2011-2013) were included. The Society for Vascular Surgery objective performance goals for CLI were used to directly compare the safety and effectiveness of PVI and BPG. Propensity score matching was used for risk-adjusted comparisons of PVI with BPG. A total of 414 patients (268 PVI, 146 BPG) were treated for tissue loss (69%) or rest pain (31%). Patients undergoing PVI were more likely to have tissue loss (74.6% vs 57.5%; P < .001) and comorbidities such as diabetes (69.3% vs 57.5%; P = .02), heart failure (22% vs 13.7%; P = .04), and severe renal disease (13.1% vs 4.1%; P = .004). No significant differences were found between the groups across a panel of safety objective performance goals. In unadjusted analyses at 1 year, BPG was associated with higher rates of freedom from reintervention, amputation, or restenosis (90.4% vs 81.7%; P = .02) and freedom from reintervention or amputation (92.5% vs 85.8%, P = .045). After propensity score matching, PVI was associated with improved freedom from major adverse limb events and postoperative death at 1 year (95.6% vs 88.5%; P < .05). By unadjusted comparison, early reintervention and restenosis are more prevalent with PVI. However, risk-adjusted comparison underscores the safety and effectiveness of PVI in the treatment of CLI. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Quantification of periodontal pathogens in vascular, blood, and subgingival samples from patients with peripheral arterial disease or abdominal aortic aneurysms.

PubMed

Figuero, Elena; Lindahl, Christeel; Marín, María José; Renvert, Stefan; Herrera, David; Ohlsson, Ola; Wetterling, Thomas; Sanz, Mariano

2014-09-01

The aim of this investigation is to quantify periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Campylobacter rectus, and Tannerella forsythia) in vascular, blood, and subgingival samples. As a secondary objective, two molecular bacterial identification methods (nested polymerase chain reaction [PCR] and quantitative PCR [qPCR]) are compared. Seventy consecutive patients provided a vascular lesion, a blood sample, and 36 subgingival samples. Bacterial DNA was extracted, and qPCR was used to determine the prevalence and amounts of the target pathogens in each sample. Nested PCR was performed only in the samples from vascular lesions. Periodontal examination was performed in 42 patients. Mann-Whitney U or χ(2) tests were used to compare microbiologic results according to periodontal diagnosis. All targeted periodontal pathogens (A. actinomycetemcomitans, P. gingivalis, T. forsythia, or C. rectus) were detected in subgingival samples, with a prevalence rate of 72.2%, 47.2%, 74.3%, and 82.9%, respectively. In 7.1% and 11.4% of vascular and blood samples, bacterial DNA was detected. One patient was positive for A. actinomycetemcomitans in the three types of samples. No differences were found in the levels of targeted bacteria when comparing patients with and without periodontitis. Prevalence rates obtained with nested PCR were significantly higher than those obtained with qPCR. The presence of A. actinomycetemcomitans was demonstrated in vascular, blood, and subgingival samples in one of 36 patients. These results, although with a very low frequency, may support the hypothesis of a translocation of periodontal pathogens from subgingival microbiota to the bloodstream and then to atheromatous plaques in carotid or other peripheral arteries. Nested PCR is not an adequate method for identifying DNA of periodontal pathogens in low quantities because of the high number of false-negative results.

Simultaneous bone marrow and composite tissue transplantation in rats treated with nonmyeloablative conditioning promotes tolerance1

PubMed Central

Xu, Hong; Ramsey, Deborah M.; Wu, Shengli; Bozulic, Larry D.; Ildstad, Suzanne T.

2012-01-01

Background Approaches to safely induce tolerance in vascularized composite allotransplantation (VCA) with chimerism through bone marrow transplantation (BMT) are currently being pursued. However, the VCA were historically performed sequentially after donor chimerism was established. Delayed VCA is not clinically applicable due to the time constraints associated with procurement from deceased donors. A more clinically relevant approach to perform both the BMT and VCA simultaneously was evaluated. Methods WF (RT1Au) rats were treated with a short course of immunosuppressive therapy (anti-αβ-TCR mAb, FK-506, and anti-lymphocyte serum). One day prior to BMT, rats were treated with varying doses of total body irradiation (TBI) followed by transplantation of heterotopic osteomyocutaneous flaps from hind limbs of ACI (RT1Aabl) rats. Results 80% of rats conditioned with 300 cGy TBI and 40% of rats receiving 400 cGy TBI accepted the VCA. Mixed chimerism was detected in peripheral blood at one month post-VCA, but chimerism was lost in all transplant recipients by 4 months. The majority of peripheral donor cells originated from the BMT and not the VCA. Acceptors of VCA were tolerant of a donor skin graft challenge and no anti-donor antibodies were detectable, suggesting a central deletional mechanism for tolerance. Regulatory T cells (Treg) from spleens of acceptors more potently suppressed lymphocyte proliferation than Treg from rejectors in the presence of donor stimulator cells. Conclusions These studies suggest that simultaneous BMT and VCA may establish indefinite allograft survival in rats through Treg-mediated suppression and thymic deletion of alloreactive T cells. PMID:23250336

Modeling plant composition as community continua in a forest landscape with LiDAR and hyperspectral remote sensing.

PubMed

Hakkenberg, C R; Peet, R K; Urban, D L; Song, C

2018-01-01

In light of the need to operationalize the mapping of forest composition at landscape scales, this study uses multi-scale nested vegetation sampling in conjunction with LiDAR-hyperspectral remotely sensed data from the G-LiHT airborne sensor to map vascular plant compositional turnover in a compositionally and structurally complex North Carolina Piedmont forest. Reflecting a shift in emphasis from remotely sensing individual crowns to detecting aggregate optical-structural properties of forest stands, predictive maps reflect the composition of entire vascular plant communities, inclusive of those species smaller than the resolution of the remotely sensed imagery, intertwined with proximate taxa, or otherwise obscured from optical sensors by dense upper canopies. Stand-scale vascular plant composition is modeled as community continua: where discrete community-unit classes at different compositional resolutions provide interpretable context for continuous gradient maps that depict n-dimensional compositional complexity as a single, consistent RGB color combination. In total, derived remotely sensed predictors explain 71%, 54%, and 48% of the variation in the first three components of vascular plant composition, respectively. Among all remotely sensed environmental gradients, topography derived from LiDAR ground returns, forest structure estimated from LiDAR all returns, and morphological-biochemical traits determined from hyperspectral imagery each significantly correspond to the three primary axes of floristic composition in the study site. Results confirm the complementarity of LiDAR and hyperspectral sensors for modeling the environmental gradients constraining landscape turnover in vascular plant composition and hold promise for predictive mapping applications spanning local land management to global ecosystem modeling. © 2017 by the Ecological Society of America.

Comprehensive mechanical characterization of PLA fabric combined with PCL to form a composite structure vascular graft.

PubMed

Li, Chaojing; Wang, Fujun; Douglas, Graeham; Zhang, Ze; Guidoin, Robert; Wang, Lu

2017-05-01

Vascular grafts made by tissue engineering processes are prone to buckling and twisting, which can impede blood flow and lead to collapse of the vessel. These vascular conduits may suffer not only from insufficient tensile strength, but also from vulnerabilities related to compression, torsion, and pulsatile pressurization. Aiming to develop a tissue engineering-inspired blood conduit, composite vascular graft (cVG) prototypes were created by combining a flexible polylactic acid (PLA) knitted fabric with a soft polycaprolactone (PCL) matrix. The graft is to be populated in-situ with cellular migration and proliferation into the device. Comprehensive characterizations probed the relationship between structure and mechanical properties of the different cVG prototypes. The composite grafts exhibited major improvements in mechanical characteristics compared to single-material devices, with particular improvement in compression and torsional resistance. A commercial expanded polytetrafluoroethylene (ePTFE) vascular graft was used as a control against the proposed composite vascular grafts. CVG devices showed high tensile strength, high bursting strength, and improved suture retention. Compression, elastic recovery, and compliance were similar to those for the ePTFE graft. Copyright © 2016 Elsevier Ltd. All rights reserved.

Angina in Women Can Be Different Than Men

MedlinePlus

... for Heart.org Arrhythmia About Arrhythmia Why Arrhythmia Matters Understand Your Risk for Arrhythmia Symptoms, Diagnosis & Monitoring ... How HBP Harms Your Health Make Changes That Matter Find HBP Tools & Resources Stroke Vascular Health Peripheral ...

Vascularized Composite Allografts: Procurement, Allocation, and Implementation.

PubMed

Rahmel, Axel

Vascularized composite allotransplantation is a continuously evolving area of modern transplant medicine. Recently, vascularized composite allografts (VCAs) have been formally classified as 'organs'. In this review, key aspects of VCA procurement are discussed, with a special focus on interaction with the procurement of classical solid organs. In addition, options for a matching and allocation system that ensures VCA donor organs are allocated to the best-suited recipients are looked at. Finally, the different steps needed to promote VCA transplantation in society in general and in the medical community in particular are highlighted.

Suppression of Peripheral Sympathetic Activity Underlies Protease-Activated Receptor 2-Mediated Hypotension

PubMed Central

Kim, Young-Hwan; Ahn, Duck-Sun; Joeng, Ji-Hyun

2014-01-01

Protease-activated receptor (PAR)-2 is expressed in endothelial cells and vascular smooth muscle cells. It plays a crucial role in regulating blood pressure via the modulation of peripheral vascular tone. Although some reports have suggested involvement of a neurogenic mechanism in PAR-2-induced hypotension, the accurate mechanism remains to be elucidated. To examine this possibility, we investigated the effect of PAR-2 activation on smooth muscle contraction evoked by electrical field stimulation (EFS) in the superior mesenteric artery. In the present study, PAR-2 agonists suppressed neurogenic contractions evoked by EFS in endothelium-denuded superior mesenteric arterial strips but did not affect contraction elicited by the external application of noradrenaline (NA). However, thrombin, a potent PAR-1 agonist, had no effect on EFS-evoked contraction. Additionally, ω-conotoxin GVIA (CgTx), a selective N-type Ca2+ channel (ICa-N) blocker, significantly inhibited EFS-evoked contraction, and this blockade almost completely occluded the suppression of EFS-evoked contraction by PAR-2 agonists. Finally, PAR-2 agonists suppressed the EFS-evoked overflow of NA in endothelium-denuded rat superior mesenteric arterial strips and this suppression was nearly completely occluded by ω-CgTx. These results suggest that activation of PAR-2 may suppress peripheral sympathetic outflow by modulating activity of ICa-N which are located in peripheral sympathetic nerve terminals, which results in PAR-2-induced hypotension. PMID:25598663

Vascular pericyte density and angiogenesis associated with adenocarcinoma of the prostate.

PubMed

Killingsworth, Murray C; Wu, Xiaojuan

2011-01-01

Angiogenesis facilitates metabolism, proliferation and metastasis of adenocarcinoma cells in the prostate, as without the development of new vasculature tumor growth cannot be sustained. However, angiogenesis is variable with the well-known phenomenon of vascular 'hotspots' seen associated with viable tumor cell mass. With the recent recognition of pericytes as molecular regulators of angiogenesis, we have examined the interaction of these cells in actively growing new vessels. Pericyte interactions with developing new vessels were examined using transmission electron microscopy. Pericyte distribution was mapped from α-SMA+ immunostained histological sections and quantified using image analysis. Data was obtained from peripheral and more central regions of 27 cases with Gleason scores of 4-9. Pericyte numbers were increased around developing new vessel sprouts at sites of luminal maturation. Numbers were reduced around the actively growing tips of migrating endothelial cells and functional new vessels. Tumor regions internal to a 500-μm peripheral band showed higher microvessel pericyte density than the peripheral region. Pericytes were found to be key cellular components of developing new vessels in adenocarcinoma of the prostate. Their numbers increased at sites of luminal maturation with these cells displaying an activated phenotype different to quiescent pericytes. Increased pericyte density was found internal to the peripheral region, suggesting more mature vessels lie more centrally. Copyright © 2011 S. Karger AG, Basel.

Exercise physiology in heart failure and preserved ejection fraction.

PubMed

Haykowsky, Mark J; Kitzman, Dalane W

2014-07-01

Recent advances in the pathophysiology of exercise intolerance in patients with heart failure with preserved ejection fraction (HFPEF) suggest that noncardiac peripheral factors contribute to the reduced peak V(o2) (peak exercise oxygen uptake) and to its improvement after endurance exercise training. A greater understanding of the peripheral skeletal muscle vascular adaptations that occur with physical conditioning may allow for tailored exercise rehabilitation programs. The identification of specific mechanisms that improve whole body and peripheral skeletal muscle oxygen uptake could establish potential therapeutic targets for medical therapies and a means to follow therapeutic response. Copyright © 2014 Elsevier Inc. All rights reserved.

The Place of Nailfold Capillaroscopy Among Instrumental Methods for Assessment of Some Peripheral Ischaemic Syndromes in Rheumatology.

PubMed

Lambova, Sevdalina N

2016-01-01

Micro- and macrovascular pathology is a frequent finding in a number of common rheumatic diseases. Secondary Raynaud's phenomenon (RP) is among the most common symptoms in systemic sclerosis and several other systemic autoimmune diseases including a broad differential diagnosis. It should be also differential from other peripheral vascular syndromes such as embolism, thrombosis, etc., some of which lead to clinical manifestation of the blue toe syndrome. The current review discusses the instrumental methods for vascular assessments. Nailfold capillaroscopy is the only method among the imaging techniques that can be used for morphological assessment of the nutritive capillaries in the nailfold area. Laser-Doppler flowmetry and laser-Doppler imaging are methods for functional assessment of microcirculation, while thermography and plethysmography reflect both blood flow in peripheral arteries and microcirculation. Doppler ultrasound and angiography visualize peripheral arteries. The choice of the appropriate instrumental method is guided by the clinical presentation. The main role of capillaroscopy is to provide differential diagnosis between primary and secondary RP. In rheumatology, capillaroscopic changes in systemic sclerosis have been recently defined as diagnostic. The appearance of abnormal capillaroscopic pattern inherits high positive predictive value for the development of a connective tissue disease that is higher than the predictive value of antinuclear antibodies. In cases of abrupt onset of peripheral ischaemia, clinical signs of critical ischaemia, unilateral or lower limb involvement, Doppler ultrasound and angiography are indicated. The most common causes for such clinical picture that may be referred to rheumatologic consultation are the antiphospholipid syndrome, mimickers of vasculitides such as atherosclerosis with cholesterol emboli, and neoplasms.

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

PubMed

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

2017-12-01

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

Relation between digital peripheral arterial tonometry and brachial artery ultrasound measures of vascular function in patients with coronary artery disease and in healthy volunteers.

PubMed

Lee, Craig R; Bass, Almasa; Ellis, Kyle; Tran, Bryant; Steele, Savanna; Caughey, Melissa; Stouffer, George A; Hinderliter, Alan L

2012-03-01

Digital peripheral arterial tonometry (PAT) is an emerging, noninvasive method to assess vascular function. The physiology underlying this phenotype, however, remains unclear. Therefore, we evaluated the relation between digital PAT and established brachial artery ultrasound measures of vascular function under basal conditions and after reactive hyperemia. Using a cross-sectional study design, digital PAT and brachial artery ultrasonography with pulsed wave Doppler were simultaneously completed at baseline and after reactive hyperemia in both those with established coronary artery disease (n = 99) and healthy volunteers with low cardiovascular disease risk (n = 40). Under basal conditions, the digital pulse volume amplitude demonstrated a significant positive correlation with the brachial artery velocity-time integral that was independent of the arterial diameter, in both the healthy volunteer (r(s) = 0.64, p <0.001) and coronary artery disease (r(s) = 0.63, p <0.001) cohorts. Similar positive relations were observed with the baseline brachial artery blood flow velocity and blood flow. In contrast, no relation between the reactive hyperemia-evoked digital PAT ratio and either brachial artery flow-mediated dilation or shear stress was observed in either cohort (p = NS). In conclusion, these findings demonstrate that the digital PAT measures of vascular function more closely reflect basal blood flow in the brachial artery than reactive hyperemia-induced changes in the arterial diameter or flow velocity, and the presence of vascular disease does not modify the physiology underlying the digital PAT phenotype. Copyright © 2012 Elsevier Inc. All rights reserved.

Surgical management in patients with coexistent coronary and cerebrovascular disease. Long-term results.

PubMed

Kaul, T K; Fields, B L; Wyatt, D A; Jones, C R; Kahn, D R

1994-11-01

Between January 1980 and December 1992, 3% (210/6,862) of our patients undergoing myocardial revascularization (CABG) had high grade (> 80%) internal carotid stenosis (CS). One hundred seventy-five of these patients with complete follow up for a minimum of 18 months were studied. Bilateral internal CS was present in 60%, and 75% had other vascular lesions, mainly as peripheral vascular disease (PVD) of the lower limb (50.8%). All patients underwent CAE (carotid endarterectomy) followed by CABG under the same anesthesia. Peripheral vascular lesions, contralateral internal CS and recurrent (n = 43) and progressive vascular lesions (n = 50), were subsequently treated as staged procedures. Hospital mortality was 3.42%. By univariate analysis significant predictors of late mortality were congestive heart failure, COPD, PVD, postoperative myocardial infarction, postoperative stroke, and ischemic cardiomyopathy. Only the latter two were also significant by multivariate analysis. At 12 years, actuarial survival in the presence of these risk factors were 46%, 49%, 22%, 37%, 53%, and 27% respectively. All are significantly lower as compared with the corresponding subsets of patients with the risk factor absent. At 12 years, actuarial survival for the entire series was 65%. Cumulative incidence of postoperative strokes was higher in patients with bilateral internal CS than in patients with unilateral internal CS (p < 0.07) and in patients with neurologic symptoms than asymptomatic patients. At 12 years, actuarial freedom from all cardiac related events, postoperative stroke, and symptomatic PVD were 49%, 82%, and 76% respectively. After successful revascularization these patients should be carefully followed for recurrent and progressive vascular lesions.

Oxidative stress as a mechanism of added sugar-induced cardiovascular disease.

PubMed

Prasad, Kailash; Dhar, Indu

2014-12-01

Added sugars comprising of table sugar, brown sugar, corn syrup, maple syrup, honey, molasses, and other sweeteners in the prepared processed foods and beverages have been implicated in the pathophysiology of cardiovascular diseases. This article deals with the reactive oxygen species (ROS) as a mechanism of sugar-induced cardiovascular diseases. There is an association between the consumption of high levels of serum glucose with cardiovascular diseases. Various sources of sugar-induced generation of ROS, including mitochondria, nicotinamide adenine dinucleotide phosphate-oxidase, advanced glycation end products, insulin, and uric acid have been discussed. The mechanism by which ROS induce the development of atherosclerosis, hypertension, peripheral vascular disease, coronary artery disease, cardiomyopathy, heart failure, and cardiac arrhythmias have been discussed in detail. In conclusion, the data suggest that added sugars induce atherosclerosis, hypertension, peripheral vascular disease, coronary artery disease, cardiomyopathy, heart failure, and cardiac arrhythmias and that these effects of added sugars are mediated through ROS.

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).

Modeling and processing of laser Doppler reactive hyperaemia signals

NASA Astrophysics Data System (ADS)

Humeau, Anne; Saumet, Jean-Louis; L'Huiller, Jean-Pierre

2003-07-01

Laser Doppler flowmetry is a non-invasive method used in the medical domain to monitor the microvascular blood cell perfusion through tissue. Most commercial laser Doppler flowmeters use an algorithm calculating the first moment of the power spectral density to give the perfusion value. Many clinical applications measure the perfusion after a vascular provocation such as a vascular occlusion. The response obtained is then called reactive hyperaemia. Target pathologies include diabetes, hypertension and peripheral arterial occlusive diseases. In order to have a deeper knowledge on reactive hyperaemia acquired by the laser Doppler technique, the present work first proposes two models (one analytical and one numerical) of the observed phenomenon. Then, a study on the multiple scattering between photons and red blood cells occurring during reactive hyperaemia is carried out. Finally, a signal processing that improves the diagnosis of peripheral arterial occlusive diseases is presented.

Detecting lower extremity vascular dynamics in patients with peripheral artery disease using diffuse optical tomography

NASA Astrophysics Data System (ADS)

Khalil, Michael A.; Kim, Hyun-Keol K.; Kim, In-Kyong; Dayal, Rajeev; Hielscher, Andreas H.

2011-02-01

Peripheral Artery Disease (PAD) affects over 10 million Americans and is associated with significant morbidity and mortality. While in many cases the ankle-brachial index (ABI) can be used for diagnosing the disease, this parameter is not dependable in the diabetic and elderly population. These populations tend to have calcified arteries, which leads to elevated ABI values. Dynamic optical tomography (DDOT) promises to overcome the limitations of the current diagnostic techniques and has the potential to initiate a paradigm shift in the diagnosis of vascular disease. We have performed initial pilot studies involving 5 PAD patients and 3 healthy volunteers. The time traces and tomographic reconstruction obtained from measurements on the feet show significant differences between healthy and affected vasculatures. In addition, we found that DOT is capable of identifying PAD in diabetic patients, who are misdiagnosed by the traditional ABI screening.

Positioning Vascularized Composite Allotransplantation in the Spectrum of Transplantation

DTIC Science & Technology

2015-10-01

composite allograft (VCA) survival without a need for maintenance immunosuppression. 12th Congress of the International Hand and Composite Tissue ...14. ABSTRACT We have continued our studies of the immune mechanisms contributing to rejection of vascularized composite allografts (VCA) in murine...models, and how these may be overcome to promote long-term allograft survival. We have now firmly established an orthotopic hind limb VCA model in our

Optoacoustic angiography of peripheral vasculature

NASA Astrophysics Data System (ADS)

Ermilov, Sergey; Su, Richard; Zamora, Mario; Hernandez, Travis; Nadvoretsky, Vyacheslav; Oraevsky, Alexander

2012-02-01

We developed a new optoacoustic microangiography system (OmAS) intended for in-vivo vascular imaging of a human finger. The system employs an arc-shaped acoustic array that is rotated 360 degrees around the finger providing optoacoustic data necessary for tomographic reconstruction of the three-dimensional images of a finger. A near-infrared Q-switched laser is used to generate optoacoustic signals with increased contrast of blood vessels. The laser is coupled through two randomized fiberoptic bundles oriented in orthogonal optoacoustic mode. To demonstrate OmAS capabilities, we present a time-series of optoacoustic images of a human finger taken after the hypothermia stress test. The images show a detailed vascular anatomy of a finger down to the capillary level. A series of quick 30s scans allowed us to visualize the thermoregulatory response within the studied finger as it was manifested via vasomotor activity during the hypothermia recovery. We propose that the developed system can be used for diagnostics of various medical conditions that are manifested in change of the peripheral (finger) blood flow. Examples of the medical conditions that could be diagnosed and staged using the OmAS include the peripheral arterial disease (PAD), thrombosis, frostbite, and traumas.

Development of a Regenerative Peripheral Nerve Interface for Control of a Neuroprosthetic Limb.

PubMed

Urbanchek, Melanie G; Kung, Theodore A; Frost, Christopher M; Martin, David C; Larkin, Lisa M; Wollstein, Adi; Cederna, Paul S

2016-01-01

Background. The purpose of this experiment was to develop a peripheral nerve interface using cultured myoblasts within a scaffold to provide a biologically stable interface while providing signal amplification for neuroprosthetic control and preventing neuroma formation. Methods. A Regenerative Peripheral Nerve Interface (RPNI) composed of a scaffold and cultured myoblasts was implanted on the end of a divided peroneal nerve in rats (n = 25). The scaffold material consisted of either silicone mesh, acellular muscle, or acellular muscle with chemically polymerized poly(3,4-ethylenedioxythiophene) conductive polymer. Average implantation time was 93 days. Electrophysiological tests were performed at endpoint to determine RPNI viability and ability to transduce neural signals. Tissue samples were examined using both light microscopy and immunohistochemistry. Results. All implanted RPNIs, regardless of scaffold type, remained viable and displayed robust vascularity. Electromyographic activity and stimulated compound muscle action potentials were successfully recorded from all RPNIs. Physiologic efferent motor action potentials were detected from RPNIs in response to sensory foot stimulation. Histology and transmission electron microscopy revealed mature muscle fibers, axonal regeneration without neuroma formation, neovascularization, and synaptogenesis. Desmin staining confirmed the preservation and maturation of myoblasts within the RPNIs. Conclusions. RPNI demonstrates significant myoblast maturation, innervation, and vascularization without neuroma formation.

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

In vivo imaging of pulmonary nodule and vasculature using endoscopic co-registered optical coherence tomography and autofluorescence imaging (Conference Presentation)

NASA Astrophysics Data System (ADS)

Pahlevaninezhad, Hamid; Lee, Anthony; Hohert, Geoffrey; Schwartz, Carely; Shaipanich, Tawimas; Ritchie, Alexander J.; Zhang, Wei; MacAulay, Calum E.; Lam, Stephen; Lane, Pierre M.

2016-03-01

Peripheral lung nodules found by CT-scans are difficult to localize and biopsy bronchoscopically particularly for those ≤ 2 cm in diameter. In this work, we present the results of endoscopic co-registered optical coherence tomography and autofluorescence imaging (OCT-AFI) of normal and abnormal peripheral airways from 40 patients using 0.9 mm diameter fiber optic rotary pullback catheter. Optical coherence tomography (OCT) can visualize detailed airway morphology endoscopically in the lung periphery. Autofluorescence imaging (AFI) can visualize fluorescing tissue components such as collagen and elastin, enabling the detection of airway lesions with high sensitivity. Results indicate that AFI of abnormal airways is different from that of normal airways, suggesting that AFI can provide a sensitive visual presentation for rapidly identifying possible sites of pulmonary nodules. AFI can also rapidly visualize in vivo vascular networks using fast scanning parameters resulting in vascular-sensitive imaging with less breathing/cardiac motion artifacts compared to Doppler OCT imaging. It is known that tumor vasculature is structurally and functionally different from normal vessels. Thus, AFI can be potentially used for differentiating normal and abnormal lung vasculature for studying vascular remodeling.

Retinal vascular abnormalities and dragged maculae in a carrier with a new NDP mutation (c.268delC) that caused severe Norrie disease in the proband.

PubMed

Lin, Phoebe; Shankar, Suma P; Duncan, Jacque; Slavotinek, Anne; Stone, Edwin M; Rutar, Tina

2010-02-01

Norrie disease (ND) is caused by mutations in the ND pseudoglioma (NDP) gene (MIM 300658) located at chromosome Xp11.4-p11.3. ND is characterized by abnormal retinal vascular development and vitreoretinal disorganization presenting at birth. Systemic manifestations include sensorineural deafness, progressive mental disorder, behavioral and psychological problems, growth failure, and seizures. Other vitreoretinopathies that are associated with NDP gene mutations include X-linked familial exudative vitreoretinopathy, Coats disease, persistent fetal vasculature, and retinopathy of prematurity. Phenotypic variability associated with NDP gene mutations has been well documented in affected male patients. However, there are limited data on signs in female carriers, with mild peripheral retinal abnormalities reported in both carrier and noncarrier females of families with NDP gene mutations. Here, we report a family harboring a single base-pair deletion, c.268delC, in the NDP gene causing a severe ND phenotype in the male proband and peripheral retinal vascular abnormalities with dragged maculae similar to those observed in familial exudative vitreoretinopathy in his carrier mother. Copyright (c) 2010 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

Phlebitis and infiltration: vascular trauma associated with the peripheral venous catheter

PubMed Central

Braga, Luciene Muniz; Parreira, Pedro Miguel; Oliveira, Anabela de Sousa Salgueiro; Mónico, Lisete dos Santos Mendes; Arreguy-Sena, Cristina; Henriques, Maria Adriana

2018-01-01

ABSTRACT Objective: to determine the incidence rate and risk factors for the nursing-sensitive indicators phlebitis and infiltration in patients with peripheral venous catheters (PVCs). Method: cohort study with 110 patients. Scales were used to assess and document phlebitis and infiltration. Socio-demographic variables, clinical variables related to the PVC, medication and hospitalization variables were collected. Descriptive and inferential analysis and multivariate logistic models were used. Results: the incidence rate of phlebitis and infiltration was respectively 43.2 and 59.7 per 1000 catheter-days. Most PVCs with these vascular traumas were removed in the first 24 hours. Risk factors for phlebitis were: length of hospital stay (p=0.042) and number of catheters inserted (p<0.001); risk factors for infiltration were: piperacillin/tazobactan (p=0.024) and the number of catheters inserted (p<0.001). Conclusion: the investigation documented the incidence of nursing-sensitive indicators (phlebitis and infiltration) and revealed new risk factors related to infiltration. It also allowed a reflection on the nursing care necessary to prevent these vascular traumas and on the indications and contraindications of the PVC, supporting the implementation of the PICC as an alternative to PVC. PMID:29791668

Increased endothelial progenitor cell circulation and VEGF production in a rat model of noise-induced hearing loss.

PubMed

Yang, Dong; Zhou, Huifang; Zhang, Jianning; Liu, Li

2015-06-01

The vascular endothelial growth factor (VEGF)-mediated mechanism of endothelial progenitor cell (EPC) mobilization, migration, and differentiation may occur in response to noise-induced acoustic trauma of the cochlea, leading to the protection of cochlear function. The purpose of this study was to analyze changes in the cochlear vessel under an intensive noise environment. Sixty male Sprague-Dawley rats were randomly divided into six groups. Acoustic trauma was induced by 120 dB SPL white noise for 4 h. Auditory function was evaluated by the auditory brainstem response threshold. Morphological changes of the cochleae, the expression of VEGF, and the circulation of EPCs in the peripheral blood were studied by immunohistochemistry, Western blotting analysis, scanning electron microscopy, and flow cytometry. Vascular recovery of the cochlea began after noise exposure. The change in the number of EPCs was consistent with the expression of VEGF at different time points after noise exposure. We propose that VEGF evokes specific permeable and chemotactic effects on the vascular endothelial cells. These effects can mobilize EPCs into the peripheral blood, leading the EPCs to target damaged sites and to exert a neoangiogenic effect.

Right line, right patient, right time: every choice matters.

PubMed

Jackson, Tim; Hallam, Carole; Corner, Tracey; Hill, Steve

The field of vascular access has developed significantly over recent decades. It has been adapted to provide a range of techniques for a range of patients much faster than a full appreciation of the risks involved has developed. Improved governance of vascular access procedures in the UK is needed. This is driven by a deeper understanding of risks such as infectious and thrombotic complications, repeated failures of peripheral intravenous (IV) access leading to poor patient experience and treatment inadequacy, and the increasing emphasis on avoiding healthcare-associated infections. The Vessel Health and Preservation (VHP) protocol, which is used to standardise vascular access practice in the US is being evaluated for adoption in the UK. A comprehensive and inclusive approach should be taken to the vascular access needs of all patients.

Austrian Lipid Consensus on the management of metabolic lipid disorders to prevent vascular complications: A joint position statement issued by eight medical societies. 2016 update.

PubMed

Toplak, Hermann; Ludvik, Bernhard; Lechleitner, Monika; Dieplinger, Hans; Föger, Bernhard; Paulweber, Bernhard; Weber, Thomas; Watschinger, Bruno; Horn, Sabine; Wascher, Thomas C; Drexel, Heinz; Brodmann, Marianne; Pilger, Ernst; Rosenkranz, Alexander; Pohanka, Erich; Oberbauer, Rainer; Traindl, Otto; Roithinger, Franz Xaver; Metzler, Bernhard; Haring, Hans-Peter; Kiechl, Stefan

2016-04-01

In 2010, eight Austrian medical societies proposed a joint position statement on the management of metabolic lipid disorders for the prevention of vascular complications. An updated and extended version of these recommendations according to the current literature is presented, referring to the primary and secondary prevention of vascular complications in adults, taking into consideration the guidelines of other societies. The "Austrian Lipid Consensus - 2016 update" provides guidance for individualized risk stratification and respective therapeutic targets, and discusses the evidence for reducing vascular endpoints with available lipid-lowering therapies. Furthermore, specific management in key patient groups is outlined, including subjects presenting with coronary, cerebrovascular, and/or peripheral atherosclerosis; diabetes mellitus and/or metabolic syndrome; nephropathy; and familial hypercholesterolemia.

IGF-1 and Chondroitinase ABC Augment Nerve Regeneration after Vascularized Composite Limb Allotransplantation.

PubMed

Kostereva, Nataliya V; Wang, Yong; Fletcher, Derek R; Unadkat, Jignesh V; Schnider, Jonas T; Komatsu, Chiaki; Yang, Yang; Stolz, Donna B; Davis, Michael R; Plock, Jan A; Gorantla, Vijay S

2016-01-01

Impaired nerve regeneration and inadequate recovery of motor and sensory function following peripheral nerve repair remain the most significant hurdles to optimal functional and quality of life outcomes in vascularized tissue allotransplantation (VCA). Neurotherapeutics such as Insulin-like Growth Factor-1 (IGF-1) and chondroitinase ABC (CH) have shown promise in augmenting or accelerating nerve regeneration in experimental models and may have potential in VCA. The aim of this study was to evaluate the efficacy of low dose IGF-1, CH or their combination (IGF-1+CH) on nerve regeneration following VCA. We used an allogeneic rat hind limb VCA model maintained on low-dose FK506 (tacrolimus) therapy to prevent rejection. Experimental animals received neurotherapeutics administered intra-operatively as multiple intraneural injections. The IGF-1 and IGF-1+CH groups received daily IGF-1 (intramuscular and intraneural injections). Histomorphometry and immunohistochemistry were used to evaluate outcomes at five weeks. Overall, compared to controls, all experimental groups showed improvements in nerve and muscle (gastrocnemius) histomorphometry. The IGF-1 group demonstrated superior distal regeneration as confirmed by Schwann cell (SC) immunohistochemistry as well as some degree of extrafascicular regeneration. IGF-1 and CH effectively promote nerve regeneration after VCA as confirmed by histomorphometric and immunohistochemical outcomes.

RECOVERY OF VASCULAR FUNCTION AFTER EXPOSURE TO A SINGLE BOUT OF SEGMENTAL VIBRATION

PubMed Central

Krajnak, Kristine; Waugh, Stacey; Miller, G. Roger; Johnson, Claud

2015-01-01

Work rotation schedules may be used to reduce the negative effects of vibration on vascular function. This study determined how long it takes vascular function to recover after a single exposure to vibration in rats (125 Hz, acceleration 5g). The responsiveness of rat-tail arteries to the vasoconstricting factor UK14304, an α2C-adrenoreceptor agonist, and the vasodilating factor acetylcholine (ACh) were measured ex vivo 1, 2, 7, or 9 d after exposure to a single bout of vibration. Vasoconstriction induced by UK14304 returned to control levels after 1 d of recovery. However, re-dilation induced by ACh did not return to baseline until after 9 d of recovery. Exposure to vibration exerted prolonged effects on peripheral vascular function, and altered vascular responses to a subsequent exposure. To optimize the positive results of work rotation schedules, it is suggested that studies assessing recovery of vascular function after exposure to a single bout of vibration be performed in humans. PMID:25072825

Vascular Damage and Kidney Transplant Outcomes: An Unfriendly and Harmful Link.

PubMed

Hernández, Domingo; Triñanes, Javier; Armas, Ana María; Ruiz-Esteban, Pedro; Alonso-Titos, Juana; Duarte, Ana; González-Molina, Miguel; Palma, Eulalia; Salido, Eduardo; Torres, Armando

2017-07-01

Kidney transplant (KT) is the treatment of choice for most patients with chronic kidney disease, but this has a high cardiovascular mortality due to traditional and nontraditional risk factors, including vascular calcification. Inflammation could precede the appearance of artery wall lesions, leading to arteriosclerosis and clinical and subclinical atherosclerosis in these patients. Additionally, mineral metabolism disorders and activation of the renin-angiotensin system could contribute to this vascular damage. Thus, understanding the vascular lesions that occur in KT recipients and the pathogenic mechanisms involved in their development could be crucial to optimize the therapeutic management and outcomes in survival of this population. This review focuses on the following issues: (1) epidemiological data framing the problem; (2) atheromatosis in KT patients: subclinical and clinical atheromatosis, involving ischemic heart disease, congestive heart failure, stroke and peripheral vascular disease; (3) arteriosclerosis and vascular calcifications; and (4) potential pathogenic mechanisms and their therapeutic targets. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

The effect of metabolic syndrome components on exercise performance in patients with intermittent claudication.

PubMed

Gardner, Andrew W; Montgomery, Polly S

2008-06-01

To determine the effect of metabolic syndrome components on intermittent claudication, physical function, health-related quality of life, and peripheral circulation in patients with peripheral arterial disease (PAD), and to identify the metabolic syndrome components most predictive of each outcome measure. Patients limited by intermittent claudication with three (n = 48), four (n = 45), or five (n = 40) components of metabolic syndrome were studied. Patients were assessed on PAD-specific measures consisting of ankle-brachial index (ABI), initial claudication distance, absolute claudication distance, physical function measures, health-related quality of life, and calf blood flow and transcutaneous oxygen tension responses after 3 minutes of vascular occlusion. Initial claudication distance (mean +/- SD) progressively declined (P = .019) in those with three (203 +/- 167 m), four (124 +/- 77 m), and five (78 +/- 57 m) metabolic syndrome components, and absolute claudication distance progressively declined (P = .036) in these groups as well (414 +/- 224 m vs 323 +/- 153 m vs 249 +/- 152 m, respectively). Furthermore, compared with patients with only three components of metabolic syndrome, those with all five components had impaired values (P < .05) for peak oxygen uptake, ischemic window, 6-minute walk distance, self-perceived walking ability and health, daily physical activity, health-related quality of life on six of eight domains, calf hyperemia, and calf ischemia after vascular occlusion. Abdominal obesity was the predictor (P < .05) of exercise performance during the treadmill and 6-minute walk tests, as well as physical activity. Elevated fasting glucose was the predictor (P < .05) of peripheral vascular measures, self-perceived walking ability and health, and health-related quality of life. PAD patients with more metabolic syndrome components have worsened intermittent claudication, physical function, health-related quality of life, and peripheral circulation. Abdominal obesity and elevated fasting glucose are the metabolic syndrome components that are most predictive of these outcome measures. Aggressively treating these metabolic syndrome components may be particularly important in managing symptoms and long-term prognosis of PAD patients.

A new Late Devonian genus with seed plant affinities.

PubMed

Wang, Deming; Liu, Le

2015-02-26

Many ovules of Late Devonian (Famennian) seed plants have been well studied. However, because few taxa occur with anatomically preserved stems and/or petioles, the vascular system of these earliest spermatophytes is little understood and available data come mostly from Euramerica. There remains great controversy over the anatomical differentiation of Late Devonian and Carboniferous seed plant groups of Buteoxylonales, Calamopityales and Lyginopteridales. Protostele evolution of these early spermatophytes needs more research. A new taxon Yiduxylon trilobum gen. et sp. nov. with seed plant affinities has been discovered in the Upper Devonian (Famennian) Tizikou Formation of Hubei Province, China. It is represented by stems, helically arranged and bifurcate fronds with two orders of pinnae and planate pinnules. Both secondary pinnae and pinnules are borne alternately. Stems contain a small protostele with three primary xylem ribs possessing a single peripheral protoxylem strand. Thick secondary xylem displays multiseriate bordered pitting on the tangential and radial walls of the tracheids, and has biseriate to multiseriate and high rays. A narrow cortex consists of inner cortex without sclerotic nests and sparganum-type outer cortex with peripheral bands of vertically aligned sclerenchyma cells. Two leaf traces successively arise tangentially from each primary xylem rib and they divide once to produce four circular-oval traces in the stem cortex. Four vascular bundles occur in two C-shaped groups at each petiole base with ground tissue and peripheral bands of sclerenchyma cells. Yiduxylon justifies the assignment to a new genus mainly because of the protostele with protoxylem strands only near the periphery of primary xylem ribs, leaf trace origination and petiolar vascular supply structure. It shares many definitive characters with Calamopityales and Lyginopteridales, further underscoring the anatomical similarities among early seed plants. The primary vascular system, pycnoxylic-manoxylic secondary xylem with bordered pits on both tangential and radial walls of a tracheid and leaf trace divergence of Yiduxylon suggest transitional features between the early spermatophytes and ancestral aneurophyte progymnosperms.

CT Angiography of Peripheral Arterial Disease by 256-Slice Scanner: Accuracy, Advantages and Disadvantages Compared to Digital Subtraction Angiography.

PubMed

Mishra, Atul; Jain, Narendra; Bhagwat, Anand

2017-07-01

Peripheral arterial occlusive disease (PAOD) may cause disabling claudication or critical limb ischemia. Multidetector computed tomography (CT) technology has evolved to the level of 256-slice CT scanners which has significantly improved the spatial and temporal resolution of the images. This has provided the capability of chasing the contrast bolus at a fast speed enabling angiographic imaging of long segments of the body. These images can be reconstructed in various planes and various modes for detailed analysis of the peripheral vascular diseases which helps in making treatment decision. The aim of this retrospective study was to compare the CT angiograms (CTAs) of all cases of PAOD done by 256-slice CT scanner at a tertiary care vascular center and comparing these images with the digital subtraction angiograms (DSAs) of these patients. The retrospective study included 53 patients who underwent both CTA and DSA at our center over a period of 3 years from March 2013 to March 2016. The CTA showed high sensitivity (93%) and specificity (92.7%) for overall assessment of degree of stenosis in a vascular segment in cases of aortic and lower limb occlusive disease. The assessment of lesions of infrapopliteal segment was comparatively inferior (sensitivity 91.6%, accuracy 73.3%, and positive predictive value 78.5%), more so in the presence of significant calcification. The advantages of CTA were its noninvasive nature, ability to image large area of body, almost no adverse effects to the patients, and better assessment of vessel wall disease. However, the CTA assessment of collaterals was inferior with a sensitivity of only 62.7% as compared to DSA. Overall, 256-slice CTA provides fast and accurate imaging of vascular tree which can restrict DSA only in few selected cases as a problem-solving tool where clinico-radiological mismatch is present.

Dacron® vs. PTFE as bypass materials in peripheral vascular surgery – systematic review and meta-analysis

PubMed Central

Roll, Stephanie; Müller-Nordhorn, Jacqueline; Keil, Thomas; Scholz, Hans; Eidt, Daniela; Greiner, Wolfgang; Willich, Stefan N

2008-01-01

Background In peripheral vascular bypass surgery different synthetic materials are available for bypass grafting. It is unclear which of the two commonly used materials, polytetrafluoroethylene (PTFE) or polyester (Dacron®) grafts, is to be preferred. Thus, the aim of this meta-analysis and systematic review was to compare the effectiveness of these two prosthetic bypass materials (Dacron® and PTFE). Methods We performed a systematic literature search in MEDLINE, Cochrane-Library – CENTRAL, EMBASE and other databases for relevant publications in English and German published between 1999 and 2008. Only randomized controlled trials were considered for inclusion. We assessed the methodological quality by means of standardized checklists. Primary patency was used as the main endpoint. Random-effect meta-analysis as well as pooling data in life table format was performed to combine study results. Results Nine randomized controlled trials (RCT) were included. Two trials showed statistically significant differences in primary patency, one favouring Dacron® and one favouring PTFE grafts, while 7 trials did not show statistically significant differences between the two materials. Meta-analysis on the comparison of PTFE vs. Dacron® grafts yielded no differences with regard to primary patency rates (hazard ratio 1.04 (95% confidence interval [0.85;1.28]), no significant heterogeneity (p = 0.32, I2 = 14%)). Similarly, there were no significant differences with regard to secondary patency rates. Conclusion Systematic evaluation and meta-analysis of randomized controlled trials comparing Dacron® and PTFE as bypass materials for peripheral vascular surgery showed no evidence of an advantage of one synthetic material over the other. PMID:19099583

Disabling Outcomes After Peripheral Vascular Catheter Insertion in a Newborn Patient: A Case of Medical Liability?

PubMed Central

Bolcato, Matteo; Russo, Marianna; Donadello, Damiano; Rodriguez, Daniele; Aprile, Anna

2017-01-01

Patient: Female, newborn Final Diagnosis: Loss of falange of the hand Symptoms: Manual disability • Pain Medication: Ampicilline Clinical Procedure: Insert vascular catheter Specialty: Forenscic Medicine Objective: Rare disease Background: The positioning of peripheral venous catheters (PVC) is an invasive procedure commonly performed in pediatrics hospital wards to obtain vascular access for the administration of fluids, medications and other intravenous (IV) therapies. Many studies exist about management of peripheral venous access in adults. On the contrary, scientific evidence on the management of this procedure in children and newborns, especially regarding the optimal duration of infusion and the possible related side effects, is still poor. To minimize the risk of phlebitis, the guidelines of the US Centers for Disease Control and Prevention suggest the replacement of the catheter every 72–96 hours in adult patients, while in pediatric patients the catheter can remain in place for the entire duration of the IV therapy, unless complications arise. Case Report: In the presented case, after the positioning of a PVC in a newborn, no clear signs/symptoms of phlebitis were registered before the sixth day and, despite the immediate removal of the catheter, the thrombotic process, secondary to phlebitis, was already occurring, causing serious and permanent disabling outcomes, susceptible to legal medical evaluation and financial compensation. Conclusions: The knowledge of this case is particularly interesting to clinicians working in the field of neonatal care and to clinical risk management services inside hospital structures, since similar cases may be the source of requests for extremely high financial compensations due to medical liability. PMID:29056746

The roles of early surgery and comorbid conditions on outcomes of severe necrotizing soft-tissue infections.

PubMed

Latifi, Rifat; Patel, Apar S; Samson, David J; Tilley, Elizabeth H; Gashi, Saranda; Bergamaschi, Roberto; El-Menyar, Ayman

2018-05-22

Severe necrotizing soft-tissue infections (NSTIs) require immediate early surgical treatment to avoid adverse outcomes. This study aims to determine the impact of early surgery and comorbid conditions on the outcomes of NSTIs. A retrospective cohort study was performed on all subjects presenting with NSTI at an academic medical center between 2005 and 2016. Patients were identified based on ICD codes. Those under the age of 18 or with intraoperative findings not consistent with NSTI diagnosis were excluded. There were 115 patients with a confirmed diagnosis of NSTI with a mean age of 55 ± 18 years; 41% were females and 55% were diabetics. Thirty percent of patients underwent early surgery (< 6 h). There were no significant differences between groups in baseline characteristics. The late group (≥ 6 h) had prolonged hospital stay (38 vs. 23 days, p < 0.008) in comparison to the early group (< 6 h). With every 1 h delay in time to surgery, there is a 0.268 day increase in length of stay, adjusted for these other variables: alcohol abuse, number of debridements, peripheral vascular disease, previous infection and clinical necrosis. Mortality was 16.5%. Multivariable analysis revealed that alcohol abuse, peripheral vascular disease, diabetes, obesity, hypothyroidism, and presence of COPD were associated with an increase in mortality. Early surgical intervention in patients with severe necrotizing soft-tissue infections reduces length of hospital stay. Presence of comorbid conditions such as alcohol abuse, peripheral vascular disease, diabetes, obesity and hypothyroidism were associated with increased mortality.

Immunological parameters, including CXCL8 (IL-8) characterize cerebro- and cardiovascular events in patients with peripheral artery diseases.

PubMed

Szomjak, E; Der, H; Kerekes, G; Veres, K; Csiba, L; Toth, J; Peter, M; Soltesz, P; Szodoray, P

2010-04-01

The most commonly occurring atherosclerotic manifestations are peripheral artery diseases (PAD). Immune-mediated processes contribute to the development of atherosclerosis, and affect the diseases outcome. The aim of the present study was to assess various immune-competent cells, cytokines and chemokines in patients with PAD and to evaluate whether the base immunological values reflect the subsequent development of cardio/cerebrovascular symptoms. One hundred sixty patients with PAD were followed-up for 42 months. At the time of enrolment, we determined blood lymphocyte subpopulations, both T-helper (Th)1/Th2-type intracytoplasmic cytokines and soluble cytokines, chemokines. Intracellular cytokines were measured on phorbol-myristate-acetate- and ionomycine- stimulated cells. Lymphocyte subgroups were quantified by flow cytometry, soluble cytokines by ELISA and intracellular cytokine levels were measured by flow cytometry. The ankle-brachial index (ABI), indicator of atherosclerosis, was also evaluated. The clinical results were correlated with the immune-parameters to assess the input of immune-inflammatory events in the propagation of vascular manifestation. CD4(+) T-cell proportions in patients with PAD with cerebro- cardio-vascular manifestations were decreased, which further reduced in patients with fatal outcome. Of circulating chemokines, IL-8 (CXCL-8) was increased in patients with subsequent cerebro- cardio-vascular manifestations, compared to those without the symptoms, and further raised in patients with fatal outcome. The percentage of interferon (IFN)-gamma positive cells showed clear negative correlation with ABI. We conclude that altered peripheral lymphocyte subsets and cytokine/chemokine imbalance play important roles in the proinflammatory cascade and reflect disease severity in patients with PAD.

Successful Retrieval of an Embolized Vascular Closure Device (Angio-Seal{sup ®}) After Peripheral Angioplasty

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jud, Philipp, E-mail: philipp.jud@medunigraz.at; Portugaller, Rupert; Bohlsen, Dennis

A 55-year-old male with peripheral arterial disease underwent angioplasty of the right lower limb arteries via antegrade femoral access. Angio-Seal{sup ®} closure device was used to treat the puncture site, whereby the intravascular sealing anchor accidentally embolized into the malleolar region of the right posterior tibial artery. Successful retrieval of the anchor was accomplished by a SpiderFX embolic protection device. This technique may be a useful approach to retrieve embolized foreign bodies via endovascular access.

Aspirin, Plavix, and Other Antiplatelet Medications: What the Oral and Maxillofacial Surgeon Needs to Know.

PubMed

Ghantous, Andre E; Ferneini, Elie M

2016-11-01

Most patients with coronary artery disease and peripheral vascular disease are on long-term antiplatelet therapy and dual therapy. Achieving a balance between ischemic and bleeding risk remains an important factor in managing patients on antiplatelet therapy. For most outpatient surgical procedures, maintenance and continuation of this therapy are recommended. Consultation with the patient's cardiologist, physician, and/or vascular surgeon is always recommended before interrupting or withholding this treatment modality. Copyright © 2016 Elsevier Inc. All rights reserved.

Immunomodulation to Optimize Vascularized Composite Allograft Integration in Limb Loss Therapy

DTIC Science & Technology

2015-10-01

2 AWARD  NUMBER:        W81XWH-­12-­2-­0058   TITLE:      Immunomodulation to Optimize Vascularized Composite Allograft Integration in Limb Loss...NUMBER   Immunomodulation to Optimize Vascularized Composite Allograft Integration in Limb Loss Therapy 5b.  GRANT  NUMBER   W81XWH-­12-­2-­0058...transplanted   tissues  are  now  available   that  may  greatly   reduce   the   risks  associated   with  limb  transplantation.       The  proposal

Behavioral Medicine.

ERIC Educational Resources Information Center

Garfield, Sol L., Ed.

1982-01-01

Contains 18 articles discussing the uses of behavioral medicine in such areas as obesity, smoking, hypertension, and headache. Reviews include discussions of behavioral medicine and insomnia, chronic pain, asthma, peripheral vascular disease, and coronary-prone behavior. Newly emerging topics include gastrointestinal disorders, arthritis,…

ARSENIC - SUSCEPTIBILITY & IN UTERO EFFECTS

EPA Science Inventory

Exposure to inorganic arsenic remains a serious public health problem at many locations worldwide. If has often been noted that prevalences of signs and symptoms of chronic arsenic poisoning differ among various populations. For example, skin lesions or peripheral vascular dis...

Peripheral Arterial Disease study (PERART): prevalence and predictive values of asymptomatic peripheral arterial occlusive disease related to cardiovascular morbidity and mortality.

PubMed

Alzamora, María Teresa; Baena-Díez, José Miguel; Sorribes, Marta; Forés, Rosa; Toran, Pere; Vicheto, Marisa; Pera, Guillem; Reina, María Dolores; Albaladejo, Carlos; Llussà, Judith; Bundó, Magda; Sancho, Amparo; Heras, Antonio; Rubiés, Joan; Arenillas, Juan Francisco

2007-12-11

The early diagnosis of atherosclerotic disease is essential for developing preventive strategies in populations at high risk and acting when the disease is still asymptomatic. A low ankle-arm index (AAI) is a good marker of vascular events and may be diminished without presenting symptomatology (silent peripheral arterial disease). The aim of the PERART study (PERipheral ARTerial disease) is to determine the prevalence of peripheral arterial disease (both silent and symptomatic) in a general population of both sexes and determine its predictive value related to morbimortality (cohort study). This cross-over, cohort study consists of 2 phases: firstly a descriptive, transversal cross-over study to determine the prevalence of peripheral arterial disease, and secondly, a cohort study to evaluate the predictive value of AAI in relation to cardiovascular morbimortality. From September 2006 to June 2007, a total of 3,010 patients over the age of 50 years will be randomly selected from a population adscribed to 24 healthcare centres in the province of Barcelona (Spain). The diagnostic criteria of peripheral arterial disease will be considered as an AAI < 0.90, determined by portable Doppler (8 Mhz probe) measured twice by trained personnel. Cardiovascular risk will be calculated with the Framingham-Wilson tables, with Framingham calibrated by the REGICOR and SCORE groups. The subjects included will be evaluted every 6 months by telephone interview and the clnical history and death registries will be reviewed. The appearance of the following cardiovascular events will be considered as variables of response: transitory ischaemic accident, ictus, angina, myocardial infartction, symptomatic abdominal aneurysm and vascular mortality. In this study we hope to determine the prevalence of peripheral arterial disease, especially the silent forms, in the general population and establish its relationship with cardiovascular morbimortality. A low AAI may be a better marker of arterial disease than the classical cardiovascular risk factors and may, therefore, contribute to improving the predictive value of the equations of cardiovascular risk and thereby allowing optimisation of multifactorial treatment of atherosclerotic disease.

Peripheral Arterial Disease Study (PERART): Prevalence and predictive values of asymptomatic peripheral arterial occlusive disease related to cardiovascular morbidity and mortality

PubMed Central

Alzamora, María Teresa; Baena-Díez, José Miguel; Sorribes, Marta; Forés, Rosa; Toran, Pere; Vicheto, Marisa; Pera, Guillem; Reina, María Dolores; Albaladejo, Carlos; Llussà, Judith; Bundó, Magda; Sancho, Amparo; Heras, Antonio; Rubiés, Joan; Arenillas, Juan Francisco

2007-01-01

Background The early diagnosis of atherosclerotic disease is essential for developing preventive strategies in populations at high risk and acting when the disease is still asymptomatic. A low ankle-arm index (AAI) is a good marker of vascular events and may be diminished without presenting symptomatology (silent peripheral arterial disease). The aim of the PERART study (PERipheral ARTerial disease) is to determine the prevalence of peripheral arterial disease (both silent and symptomatic) in a general population of both sexes and determine its predictive value related to morbimortality (cohort study). Methods/Design This cross-over, cohort study consists of 2 phases: firstly a descriptive, transversal cross-over study to determine the prevalence of peripheral arterial disease, and secondly, a cohort study to evaluate the predictive value of AAI in relation to cardiovascular morbimortality. From September 2006 to June 2007, a total of 3,010 patients over the age of 50 years will be randomly selected from a population adscribed to 24 healthcare centres in the province of Barcelona (Spain). The diagnostic criteria of peripheral arterial disease will be considered as an AAI < 0.90, determined by portable Doppler (8 Mhz probe) measured twice by trained personnel. Cardiovascular risk will be calculated with the Framingham-Wilson tables, with Framingham calibrated by the REGICOR and SCORE groups. The subjects included will be evaluted every 6 months by telephone interview and the clnical history and death registries will be reviewed. The appearance of the following cardiovascular events will be considered as variables of response: transitory ischaemic accident, ictus, angina, myocardial infartction, symptomatic abdominal aneurysm and vascular mortality. Discussion In this study we hope to determine the prevalence of peripheral arterial disease, especially the silent forms, in the general population and establish its relationship with cardiovascular morbimortality. A low AAI may be a better marker of arterial disease than the classical cardiovascular risk factors and may, therefore, contribute to improving the predictive value of the equations of cardiovascular risk and thereby allowing optimisation of multifactorial treatment of atherosclerotic disease. PMID:18070367

Hematopoietic stem cell capture and directional differentiation into vascular endothelial cells for metal stent-coated chitosan/hyaluronic acid loading CD133 antibody.

PubMed

Zhang, Shixuan; Zhang, Fan; Feng, Bo; Fan, Qingyu; Yang, Feng; Shang, Debin; Sui, Jinghan; Zhao, Hong

2015-03-01

A series of metal stents coated with chitosan/hyaluronic acid (CS/HA) loading antibodies by electrostatic self-assembled method were prepared, and the types of cells captured by antibodies and their differentiation in vascular endothelial cells (ECs) evaluated by molecular biology and scanning electron microscope. The results showed that CD133 stent can selectively capture hematopoietic stem cells (HSC),which directionally differentiate into vascular ECs in peripheral blood by (CS/HA) induction, and simultaneously inhibit migration and proliferation of immune cells and vascular smooth muscle cells (MCs). CD34 stent can capture HSC, hematopoietic progenitor cells that differentiate into vascular ECs and immune cells, promoting smooth MCs growth, leading to thrombosis, inflammation, and rejection. CD133 stent can be implanted into miniature pig heart coronary and can repair vascular damage by capturing own HSC, thus contributing to the rapid natural vascular repair, avoiding inflammation and rejection, thrombosis and restenosis. These studies demonstrated that CD133 stent of HSC capture will be an ideal coated metal stent providing a new therapeutic approach for cardiovascular and cerebrovascular disease.

Positioning Bascularized Composite Allotransplantation with the Spectrum of Transplantion

DTIC Science & Technology

2015-10-01

therapeutic option for patients in need of advanced tissue reconstruction. II. Keywords Biorepository, vascularized composite allograft , nonhuman primates... tissues (e.g. hand, face) into a useful therapeutic option for individuals in need of advance tissue reconstruction and replacement. The proposal...death but increased the rate of soft tissue injury. Vascularized composite allotransplantation (VCA) has recently emerged as a promising strategy for

Simultaneous Scalp, Skull, Kidney, and Pancreas Transplant from a Single Donor.

PubMed

Selber, Jesse C; Chang, Edward I; Clemens, Mark W; Gaber, Lilian; Hanasono, Matthew M; Klebuc, Michael; Skoracki, Roman J; Trask, Todd; Yu, Peirong; Gaber, A Osama

2016-06-01

Vascularized composite allotransplantation is an emerging field, but the complications of lifelong immunosuppression limit indications. Vascularized composite allotransplantation in solid organ recipients represents a unique opportunity because immunosuppression has already been accepted. This report of a simultaneous scalp, skull, kidney, and pancreas transplant represents both the first skull-scalp transplant and combination of a vascularized composite allotransplantation with double organ transplantation. A previous recipient of a kidney-pancreas transplant presented with osteoradionecrosis of the calvaria and a large area of unstable scalp following successful, curative treatment of a scalp tumor. His kidney and pancreas functions were also critically poor. A multidisciplinary, multi-institutional plan was developed to perform a simultaneous scalp, skull, and repeated kidney and pancreas transplantation, all from a single donor. Eighteen months after the patient was listed with the United Network for Organ Sharing, a donor was identified and the multiorgan vascularized composite allotransplantation was performed. Twenty physicians and 15 hours were required to perform donor and recipient procedures. The patient recovered well and was discharged on postoperative day 15. He has had one episode of scalp rejection confirmed by biopsy and treated successfully. His creatinine value is currently 0.8 mg/dl, from 5.0 mg/dl, and his blood glucose levels are normal without supplemental insulin. Aesthetic outcome is very satisfactory. The patient is now 1 year post-transplantation and doing well. Vascularized composite allotransplantation in solid organ recipients is an expansion of current indications to already immunosuppressed patients. Rejection of the vascularized composite allotransplant without solid organ rejection can occur and is treatable. Methodical planning, an interdisciplinary approach, and careful management of all organs are critical to success. Therapeutic, V.

Burden of Intracranial Atherosclerosis Is Associated With Long-Term Vascular Outcome in Patients With Ischemic Stroke.

PubMed

Kim, Byung-Su; Chung, Pil-Wook; Park, Kwang-Yeol; Won, Hong-Hee; Bang, Oh Young; Chung, Chin-Sang; Lee, Kwang Ho; Kim, Gyeong-Moon

2017-10-01

Ischemic stroke patients often have intracranial atherosclerosis (ICAS), despite heterogeneity in the cause of stroke. We tested the hypothesis that ICAS burden can independently reflect the risk of long-term vascular outcome. This was a retrospective cohort study analyzing data from a prospective stroke registry enrolling consecutive patients with acute ischemic stroke or transient ischemic attack. A total of 1081 patients were categorized into no ICAS, single ICAS, and advanced ICAS (ICAS ≥2 different intracranial arteries) groups. Primary and secondary end points were time to occurrence of recurrent ischemic stroke and composite vascular outcome, respectively. Study end points by ICAS burden were compared using Cox proportional hazards models in overall and propensity-matched patients. ICAS was present in 405 patients (37.3%). During a median 5-year follow-up, recurrent stroke and composite vascular outcome occurred in 6.8% and 16.8% of patients, respectively. As the number of ICAS increased, the risk for study end points increased after adjustment of potential covariates (hazard ratio per 1 increase in ICAS, 1.19; 95% confidence interval, 1.01-1.42 for recurrent ischemic stroke and hazard ratio, 1.18; 95% confidence interval, 1.05-1.33 for composite vascular outcome). The hazard ratios (95% confidence interval) for recurrent stroke and composite vascular outcome in patients with advanced ICAS compared with those without ICAS were 1.56 (0.88-2.74) and 1.72 (1.17-2.53), respectively, in the overall patients. The corresponding values in the propensity-matched patients were 1.28 (0.71-2.30) and 1.95 (1.27-2.99), respectively. ICAS burden was independently associated with the risk of subsequent composite vascular outcome in patients with ischemic stroke. These findings suggest that ICAS burden can reflect the risk of long-term vascular outcome. © 2017 American Heart Association, Inc.

Peripheral retinopathy in offspring of carriers of Norrie disease gene mutations. Possible transplacental effect of abnormal Norrin.

PubMed

Mintz-Hittner, H A; Ferrell, R E; Sims, K B; Fernandez, K M; Gemmell, B S; Satriano, D R; Caster, J; Kretzer, F L

1996-12-01

The Norrie disease (ND) gene (Xp11.3) (McKusick 310600) consists of one untranslated exon and two exons partially translated as the Norrie disease protein (Norrin). Norrin has sequence homology and computer-predicted tertiary structure of a growth factor containing a cystine knot motif, which affects endothelial cell migration and proliferation. Norrie disease (congenital retinal detachment), X-linked primary retinal dysplasia (congenital retinal fold), and X-linked exudative vitreoretinopathy (congenital macular ectopia) are allelic disorders. Blood was drawn for genetic studies from members of two families to test for ND gene mutations. Sixteen unaffected family members were examined ophthalmologically. If any retinal abnormality were identified, fundus photography and fluorescein angiography was performed. Family A had ND (R109stp), and family B had X-linked exudative vitreoretinopathy (R121L). The retinas of 11 offspring of carrier females were examined: three of seven carrier females, three of three otherwise healthy females, and one of one otherwise healthy male had peripheral inner retinal vascular abnormalities. The retinas of five offspring of affected males were examined: none of three carrier females and none of two otherwise healthy males had this peripheral retinal finding. Peripheral inner retinal vascular abnormalities similar to regressed retinopathy of prematurity were identified in seven offspring of carriers of ND gene mutations in two families. These ophthalmologic findings, especially in four genetically healthy offspring, strongly support the hypothesis that abnormal Norrin may have an adverse transplacental (environmental) effect on normal inner retinal vasculogenesis.

Assessment of vascularization and myelination following peripheral nerve repair using angiographic and polarization sensitive optical coherence tomography (Conference Presentation)

NASA Astrophysics Data System (ADS)

Nam, Ahhyun S.; Chico-Calero, Isabel; Easow, Jeena M.; Villiger, Martin; Welt, Jonathan; Winograd, Jonathan M.; Randolph, Mark A.; Redmond, Robert W.; Vakoc, Benjamin J.

2017-02-01

A severe traumatic injury to a peripheral nerve often requires surgical graft repair. However, functional recovery after these surgical repairs is often unsatisfactory. To improve interventional procedures, it is important to understand the regeneration of the nerve grafts. The rodent sciatic nerve is commonly used to investigate these parameters. However, the ability to longitudinally assess the reinnervation of injured nerves are limited, and to our knowledge, no methods currently exist to investigate the timing of the revascularization in functional recovery. In this work, we describe the development and use of angiographic and polarization-sensitive (PS) optical coherence tomography (OCT) to visualize the vascularization, demyelination and remyelination of peripheral nerve healing after crush and transection injuries, and across a variety of graft repair methods. A microscope was customized to provide 3.6 cm fields of view along the nerve axis with a capability to track the nerve height to maintain the nerve within the focal plane. Motion artifact rejection was implemented in the angiography algorithm to reduce degradation by bulk respiratory motion in the hindlimb site. Vectorial birefringence imaging methods were developed to significantly enhance the accuracy of myelination measurements and to discriminate birefringent contributions from the myelin and epineurium. These results demonstrate that the OCT platform has the potential to reveal new insights in preclinical studies and may ultimately provide a means for clinical intra-surgical assessment of peripheral nerve function.

Vasoregression: A Shared Vascular Pathology Underlying Macrovascular And Microvascular Pathologies?

PubMed Central

Gupta, Akanksha

2015-01-01

Abstract Vasoregression is a common phenomenon underlying physiological vessel development as well as pathological microvascular diseases leading to peripheral neuropathy, nephropathy, and vascular oculopathies. In this review, we describe the hallmarks and pathways of vasoregression. We argue here that there is a parallel between characteristic features of vasoregression in the ocular microvessels and atherosclerosis in the larger vessels. Shared molecular pathways and molecular effectors in the two conditions are outlined, thus highlighting the possible systemic causes of local vascular diseases. Our review gives us a system-wide insight into factors leading to multiple synchronous vascular diseases. Because shared molecular pathways might usefully address the diagnostic and therapeutic needs of multiple common complex diseases, the literature analysis presented here is of broad interest to readership in integrative biology, rational drug development and systems medicine. PMID:26669709

Advances in atheroma imaging in the carotid.

PubMed

Gillard, Jonathan H

2007-01-01

Atherosclerosis affects all vascular beds, including the coronary, carotid, intracerebral, peripheral and aortic vascular beds, and is responsible for tremendous morbidity and mortality, with the most serious outcomes being myocardial infarction, stroke and death. Historically the effects of vascular narrowing and associated thrombosis have been key indicators of disease in the coronary and carotid territories, with degrees of vascular stenosis being of profound importance in carotid surgery trials. Our improving understanding of the biology of atheromatous lesions and the development of alternative therapeutic agents which can initiate actual plaque regression have created a need to attempt to image plaque itself, with the carotid artery being an achievable target. This article reviews current strategies for assessing carotid atherosclerotic disease, particularly with reference to identifying plaque components and risk of rupture, the so-called vulnerable plaque. Copyright 2007 S. Karger AG, Basel.

Biochemical factors modulating female genital sexual arousal physiology.

PubMed

Traish, Abdulmaged M; Botchevar, Ella; Kim, Noel N

2010-09-01

Female genital sexual arousal responses are complex neurophysiological processes consisting of central and peripheral components that occur following sexual stimulation. The peripheral responses in sexual arousal include genital vasocongestion, engorgement and lubrication resulting from a surge of vaginal and clitoral blood flow. These hemodynamic events are mediated by a host of neurotransmitters and vasoactive agents. To discuss the role of various biochemical factors modulating female genital sexual arousal responses. A comprehensive literature review was conducted using the PubMed database and citations were selected, based on topical relevance, and examined for study methodology and major findings. Data from peer-reviewed publications. Adrenergic as well as non-adrenergic non-cholinergic neurotransmitters play an important role in regulating genital physiological responses by mediating vascular and non-vascular smooth muscle contractility. Vasoactive peptides and neuropeptides also modulate genital sexual responses by regulating vascular and non-vascular smooth muscle cells and epithelial function. The endocrine milieu, particularly sex steroid hormones, is critical in the maintenance of tissue structure and function. Reduced levels of estrogens and androgen are associated with dramatic alterations in genital tissue structure, including the nerve network, as well as the response to physiological modulators. Furthermore, estrogen and androgen deficiency is associated with reduced expression of sex steroid receptors and most importantly with attenuated genital blood flow and lubrication in response to pelvic nerve stimulation. This article provides an integrated framework describing the physiological and molecular basis of various pathophysiological conditions associated with female genital sexual arousal dysfunction. © 2010 International Society for Sexual Medicine.

Endothelial progenitor cells bind and inhibit platelet function and thrombus formation.

PubMed

Abou-Saleh, Haissam; Yacoub, Daniel; Théorêt, Jean-François; Gillis, Marc-Antoine; Neagoe, Paul-Eduard; Labarthe, Benoit; Théroux, Pierre; Sirois, Martin G; Tabrizian, Maryam; Thorin, Eric; Merhi, Yahye

2009-12-01

Interactions of endothelial progenitor cells (EPCs) with vascular and blood cells contribute to vascular homeostasis. Although platelets promote the homing of EPCs to sites of vascular injury and their differentiation into endothelial cells, the functional consequences of such interactions on platelets remain unknown. Herein, we addressed the interactions between EPCs and platelets and their impact on platelet function and thrombus formation. Cultured on fibronectin in conditioned media, human peripheral blood mononuclear cells differentiated, within 10 days of culture, into EPCs, which uptake acetylated low-density lipoprotein, bind ulex-lectin, lack monocyte/leukocyte markers (CD14, P-selectin glycoprotein ligand-1, L-selectin), express progenitor/endothelial markers (CD34, vascular endothelial growth factor receptor-2, von Willebrand factor, and vascular endothelial cadherin), and proliferate in culture. These EPCs bound activated platelets via CD62P and inhibited its translocation, glycoprotein IIb/IIIa activation, aggregation, and adhesion to collagen, mainly via prostacyclin secretion. Indeed, this was associated with upregulation of cyclooxygenase-2 and inducible nitric oxide synthase. However, the effects on platelets in vitro were reversed by cyclooxygenase and cyclooxygenase-2 inhibition but not by nitric oxide or inducible nitric oxide synthase inhibition. Moreover, in a ferric chloride-induced murine arterial thrombosis model, injection of EPCs led to their incorporation into sites of injury and impaired thrombus formation, leading to an incomplete occlusion with 50% residual flow. Peripheral blood mononuclear cell-derived EPCs bind platelets via CD62P and inhibit platelet activation, aggregation, adhesion to collagen, and thrombus formation, predominantly via upregulation of cyclooxygenase-2 and secretion of prostacyclin. These findings add new insights into the biology of EPCs and define their potential roles in regulating platelet function and thrombosis.

Endothelial Progenitor Cells Bind and Inhibit Platelet Function and Thrombus Formation

PubMed Central

Abou-Saleh, Haissam; Yacoub, Daniel; Théorêt, Jean-François; Gillis, Marc-Antoine; Neagoe, Paul-Eduard; Labarthe, Benoit; Théroux, Pierre; Sirois, Martin G.; Tabrizian, Maryam; Thorin, Eric; Merhi, Yahye

2013-01-01

Background Interactions of endothelial progenitor cells (EPCs) with vascular and blood cells contribute to vascular homeostasis. Although platelets promote the homing of EPCs to sites of vascular injury and their differentiation into endothelial cells, the functional consequences of such interactions on platelets remain unknown. Herein, we addressed the interactions between EPCs and platelets and their impact on platelet function and thrombus formation. Methods and Results Cultured on fibronectin in conditioned media, human peripheral blood mononuclear cells differentiated, within 10 days of culture, into EPCs, which uptake acetylated low-density lipoprotein, bind ulex-lectin, lack monocyte/leukocyte markers (CD14, P-selectin glycoprotein ligand-1, L-selectin), express progenitor/endothelial markers (CD34, vascular endothelial growth factor receptor-2, von Willebrand factor, and vascular endothelial cadherin), and proliferate in culture. These EPCs bound activated platelets via CD62P and inhibited its translocation, glycoprotein IIb/IIIa activation, aggregation, and adhesion to collagen, mainly via prostacyclin secretion. Indeed, this was associated with upregulation of cyclooxygenase-2 and inducible nitric oxide synthase. However, the effects on platelets in vitro were reversed by cyclooxygenase and cyclooxygenase-2 inhibition but not by nitric oxide or inducible nitric oxide synthase inhibition. Moreover, in a ferric chloride–induced murine arterial thrombosis model, injection of EPCs led to their incorporation into sites of injury and impaired thrombus formation, leading to an incomplete occlusion with 50% residual flow. Conclusions Peripheral blood mononuclear cell– derived EPCs bind platelets via CD62P and inhibit platelet activation, aggregation, adhesion to collagen, and thrombus formation, predominantly via upregulation of cyclooxygenase-2 and secretion of prostacyclin. These findings add new insights into the biology of EPCs and define their potential roles in regulating platelet function and thrombosis. PMID:19917882

Billing code algorithms to identify cases of peripheral artery disease from administrative data

PubMed Central

Fan, Jin; Arruda-Olson, Adelaide M; Leibson, Cynthia L; Smith, Carin; Liu, Guanghui; Bailey, Kent R; Kullo, Iftikhar J

2013-01-01

Objective To construct and validate billing code algorithms for identifying patients with peripheral arterial disease (PAD). Methods We extracted all encounters and line item details including PAD-related billing codes at Mayo Clinic Rochester, Minnesota, between July 1, 1997 and June 30, 2008; 22 712 patients evaluated in the vascular laboratory were divided into training and validation sets. Multiple logistic regression analysis was used to create an integer code score from the training dataset, and this was tested in the validation set. We applied a model-based code algorithm to patients evaluated in the vascular laboratory and compared this with a simpler algorithm (presence of at least one of the ICD-9 PAD codes 440.20–440.29). We also applied both algorithms to a community-based sample (n=4420), followed by a manual review. Results The logistic regression model performed well in both training and validation datasets (c statistic=0.91). In patients evaluated in the vascular laboratory, the model-based code algorithm provided better negative predictive value. The simpler algorithm was reasonably accurate for identification of PAD status, with lesser sensitivity and greater specificity. In the community-based sample, the sensitivity (38.7% vs 68.0%) of the simpler algorithm was much lower, whereas the specificity (92.0% vs 87.6%) was higher than the model-based algorithm. Conclusions A model-based billing code algorithm had reasonable accuracy in identifying PAD cases from the community, and in patients referred to the non-invasive vascular laboratory. The simpler algorithm had reasonable accuracy for identification of PAD in patients referred to the vascular laboratory but was significantly less sensitive in a community-based sample. PMID:24166724

Using a multimedia presentation to improve patient understanding and satisfaction with informed consent for minimally invasive vascular procedures.

PubMed

Bowers, N; Eisenberg, E; Montbriand, J; Jaskolka, J; Roche-Nagle, G

2017-02-01

As vascular procedures become more complex, patient understanding of their treatment(s) can become more difficult. We wished to evaluate the utility of multimedia presentations (MPs) to improve patient understanding of their vascular interventions. Patients undergoing endovascular aneurysm repair (EVAR), peripheral angioplasty, Hickman catheter and peripherally inserted central catheter (PICC) insertion were randomized into a control group receiving traditional verbal consent, and a MP group that were shown a two minute simplified video of their procedure on an iPad™ computer in addition to the traditional verbal consent. After obtaining consent, all patients completed a questionnaire assessing their comprehension of the procedure, and satisfaction with the consent process. Satisfaction was rated on a 5 point Likert scale with 5 being 'very helpful' in understanding the procedure. Ninety-three patients were recruited for this study, 62% of which were male. The intervention significantly increased total comprehension in all procedure types controlling for procedure type (multimedia vs. control; F = 9.14, P = .003). A second ANOVA showed there was a significant main effect by intervention (F = 44.06, p < .000) with those in the intervention group showing higher overall satisfaction scores after controlling for surgery type. This study suggests that patients find the use of MP during the consent process to be helpful in patient understanding and that there is improved satisfaction. Given the rapid rate of innovation in vascular interventions, increased regular use of MPs to help patients understand their procedures would be beneficial in the care of patients undergoing vascular interventions. Copyright © 2015 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

Endothelin A receptor antagonists in congestive heart failure: blocking the beast while leaving the beauty untouched?

PubMed

Spieker, L E; Noll, G; Ruschitzka, F T; Lüscher, T F

2001-12-01

Congestive heart failure (CHF) is a disease process characterized by impaired left ventricular function, increased peripheral and pulmonary vascular resistance and reduced exercise tolerance and dyspnea. Thus, mediators involved in the control of myocardial function and vascular tone may be involved in its pathophysiology. The family of endothelins (ET) consists of four closely related peptides, ET-1, ET-2, ET-3, and ET-4, which cause vasoconstriction, cell proliferation, and myocardial effects through activation of ET(A) receptors. In contrast, endothelial ET(B) receptors mediate vasodilation via release of nitric oxide and prostacyclin. In addition, ET(B) receptors in the lung are a major pathway for the clearance of ET-1 from plasma. Thus, infusion of an ET(A) receptor antagonist into the brachial artery in healthy humans leads to vasodilation whereas infusion of an ET(B) receptor antagonist causes vasoconstriction. ET-1 plasma levels are elevated in CHF and correlate both with the hemodynamic severity and with symptoms. Plasma levels of ET-1 and its precursor, big ET-1, are strong independent predictors of death in patients after myocardial infarction and with CHF. ET-1 contributes to increased systemic and pulmonary vascular resistance, vascular dysfunction, myocardial ischemia, and renal impairment in CHF. Selective ET(A) as well as combined ET(A/B) receptor antagonists have been studied in patients with CHF showing impressive hemodynamic improvements (i.e. reduced peripheral vascular and pulmonary resistance as well as increased cardiac output). These results indicate that ET receptor antagonists indeed have a potential to improve hemodynamics, symptoms, and potentially prognosis of CHF which still carries a high mortality.

The relation of digital vascular function to cardiovascular risk factors in African-Americans using digital tonometry: the Jackson Heart Study.

PubMed

McClendon, Eric E; Musani, Solomon K; Samdarshi, Tandaw E; Khaire, Sushant; Stokes, Donny; Hamburg, Naomi M; Sheffy, Koby; Mitchell, Gary F; Taylor, Herman R; Benjamin, Emelia J; Fox, Ervin R

2017-06-01

Digital vascular tone and function, as measured by peripheral arterial tonometry (PAT), are associated with cardiovascular risk and events in non-Hispanic whites. There are limited data on relations between PAT and cardiovascular risk in African-Americans. PAT was performed on a subset of Jackson Heart Study participants using a fingertip tonometry device. Resting digital vascular tone was assessed as baseline pulse amplitude. Hyperemic vascular response to 5 minutes of ischemia was expressed as the PAT ratio (hyperemic/baseline amplitude ratio). Peripheral augmentation index (AI), a measure of relative wave reflection, also was estimated. The association of baseline pulse amplitude (PA), PAT ratio, and AI to risk factors was assessed using stepwise multivariable models. The study sample consisted of 837 participants from the Jackson Heart Study (mean age, 54 ± 11 years; 61% women). In stepwise multivariable regression models, baseline pulse amplitude was related to male sex, body mass index, and diastolic blood pressure (BP), accounting for 16% of the total variability of the baseline pulse amplitude. Age, male sex, systolic BP, diastolic BP, antihypertensive medication, and prevalent cardiovascular disease contributed to 11% of the total variability of the PAT ratio. Risk factors (primarily age, sex, and heart rate) explained 47% of the total variability of the AI. We confirmed in our cohort of African-Americans, a significant relation between digital vascular tone and function measured by PAT and multiple traditional cardiovascular risk factors. Further studies are warranted to investigate the utility of these measurements in predicting clinical outcomes in African-Americans. Copyright © 2017 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

Scabies in a bilateral hand allograft recipient: An additional mimicker of acute skin rejection in vascularized composite allotransplantation.

PubMed

Kanitakis, Jean; Morelon, Emmanuel

2017-06-01

Vascularized composite tissue allografts include skin, which frequently undergoes, in the early post-graft period, acute rejections. The diagnosis of acute rejection may be difficult as it can be mimicked by several dermatoses. We present a bilateral hand allograft recipient who developed, 16.5 years post-graft, cutaneous lesions raising suspicion about rejection. Physical examination and skin biopsy were diagnostic of scabies. This ectoparasitosis should be added in the list of dermatoses that can mimic allograft rejection in vascular composite allografts. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Long-Term Tolerance Towards Haploidentical Vascularized Composite Allograft Transplantation in a Canine Model Using Bone Marrow or Mobilized Stem Cells

PubMed Central

Chang, Jeff; Graves, Scott S.; Butts-Miwongtum, Tiffany; Sale, George E.; Storb, Rainer; Mathes, David W.

2017-01-01

Background The development of safe and reliable protocols for the transplantation of the face and hands may be accomplished with animal modeling of transplantation of vascularized composite allografts (VCA). Previously, we demonstrated that tolerance to a VCA could be achieved after canine recipients were simultaneously given marrow from a dog leukocyte antigen (DLA) identical donor. In the present study, we extend those findings across a DLA mismatched barrier. Methods Eight Recipient dogs received total body irradiation (4.5 cGy), hematopoietic cell transplantation (HCT), either marrow (n=4) or granulocyte-colony stimulating factor (G-CSF) mobilized peripheral blood stem cells (n=4), and a VCA transplant from the HCT donor. Post grafting immunosuppression consisted of mycophenolate mofetil (28 days) and cyclosporine (35 days). Results In 4 dogs receiving bone marrow, 1 accepted both its marrow transplant and demonstrated long-term tolerance to the donor VCA (>52 weeks). Three dogs rejected both their marrow transplants and VCA at 5–7 weeks posttransplant. Dogs receiving mobilized stem cells all accepted their stem cell transplant and became tolerant to the VCA. However, 3 dogs developed graft-versus-host disease (GVHD) while 1 dog rejected its stem cell graft by week 15 but exhibited long-term tolerance towards its VCA (>90 weeks). Conclusion The data suggest that simultaneous transplantation of mobilized stem cells and a VCA is feasible and leads to tolerance towards the VCA in a haploidentical setting. However, there is a higher rate of donor stem cell engraftment compared to marrow HCT and an increase in the incidence of GVHD. PMID:27861292

Effects of upper-extremity vascular access creation on cardiac events in patients undergoing coronary artery bypass grafting.

PubMed

Han, Youngjin; Choo, Suk Jung; Kwon, Hyunwook; Lee, Jae Won; Chung, Cheol Hyun; Kim, Hyangkyoung; Kwon, Tae-Won; Cho, Yong-Pil

2017-01-01

The present study was conducted to investigate whether upper-extremity vascular access (VA) creation increases the risk for major adverse cardiac events (MACE) and death in patients undergoing coronary artery bypass grafting (CABG) with an in situ left internal thoracic artery (ITA) graft. A total of 111 patients with CABG with a left ITA graft who underwent upper-extremity VA creation were analyzed retrospectively; 93 patients received left VA creation (83.8%, ipsilateral group) and 18 patients received right VA creation (16.2%, contralateral group). The primary outcome was the occurrence of MACE, and the secondary outcome was the composite of MACE or late death. There were no significant differences in the incidence of primary (P = 0.30) or secondary (P = 0.09) outcomes between the two groups. Multivariate regression analysis indicated that prior cerebrovascular accidents (hazard ratio [HR] 3.30; 95% confidence interval [CI] 1.37-7.97; P = 0.01) and type of VA (HR 3.44; 95% CI 1.34-8.82; P = 0.01) were independently associated with MACE; prior peripheral arterial occlusive disease (HR 4.22; 95% CI 1.62-10.98; P<0.01) and type of VA (arteriovenous fistula vs. prosthetic arteriovenous grafting) (HR 3.06; 95% CI, 1.42-6.61; P<0.01) were associated with the composite of MACE or death. The side and location of VA were not associated with MACE or death. Our study showed no definite evidence that ipsilateral VA creation affects the subsequent occurrence of MACE or late death from any cause. The type of VA (a prosthetic arteriovenous grafting) is a significant predictor of the subsequent occurrence of MACE or late death.

Effects of upper-extremity vascular access creation on cardiac events in patients undergoing coronary artery bypass grafting

PubMed Central

Han, Youngjin; Choo, Suk Jung; Kwon, Hyunwook; Lee, Jae Won; Chung, Cheol Hyun; Kim, Hyangkyoung; Kwon, Tae-Won

2017-01-01

The present study was conducted to investigate whether upper-extremity vascular access (VA) creation increases the risk for major adverse cardiac events (MACE) and death in patients undergoing coronary artery bypass grafting (CABG) with an in situ left internal thoracic artery (ITA) graft. A total of 111 patients with CABG with a left ITA graft who underwent upper-extremity VA creation were analyzed retrospectively; 93 patients received left VA creation (83.8%, ipsilateral group) and 18 patients received right VA creation (16.2%, contralateral group). The primary outcome was the occurrence of MACE, and the secondary outcome was the composite of MACE or late death. There were no significant differences in the incidence of primary (P = 0.30) or secondary (P = 0.09) outcomes between the two groups. Multivariate regression analysis indicated that prior cerebrovascular accidents (hazard ratio [HR] 3.30; 95% confidence interval [CI] 1.37–7.97; P = 0.01) and type of VA (HR 3.44; 95% CI 1.34–8.82; P = 0.01) were independently associated with MACE; prior peripheral arterial occlusive disease (HR 4.22; 95% CI 1.62–10.98; P<0.01) and type of VA (arteriovenous fistula vs. prosthetic arteriovenous grafting) (HR 3.06; 95% CI, 1.42–6.61; P<0.01) were associated with the composite of MACE or death. The side and location of VA were not associated with MACE or death. Our study showed no definite evidence that ipsilateral VA creation affects the subsequent occurrence of MACE or late death from any cause. The type of VA (a prosthetic arteriovenous grafting) is a significant predictor of the subsequent occurrence of MACE or late death. PMID:28873444

Design of a Randomized Placebo-Controlled Trial to Assess Dabigatran and Omeprazole in Patients with Myocardial Injury after Noncardiac Surgery (MANAGE).

PubMed

Duceppe, Emmanuelle; Yusuf, Salim; Tandon, Vikas; Rodseth, Reitze; Biccard, Bruce M; Xavier, Denis; Szczeklik, Wojciech; Meyhoff, Christian S; Franzosi, Maria Grazia; Vincent, Jessica; Srinathan, Sadeesh K; Parlow, Joel; Magloire, Patrick; Neary, John; Rao, Mangala; Chaudhry, Navneet K; Mayosi, Bongani; de Nadal, Miriam; Popova, Ekaterine; Villar, Juan Carlos; Botto, Fernando; Berwanger, Otavio; Guyatt, Gordon; Eikelboom, John W; Sessler, Daniel I; Kearon, Clive; Pettit, Shirley; Connolly, Stuart J; Sharma, Mukul; Bangdiwala, Shrikant I; Devereaux, P J

2018-03-01

Worldwide approximately 200 million adults undergo major surgery annually, of whom 8 million are estimated to suffer a myocardial injury after noncardiac surgery (MINS). There is currently no trial data informing the management of MINS. Antithrombotic agents such as direct oral anticoagulants might prevent major vascular complications in patients with MINS. The Management of Myocardial Injury After Noncardiac Surgery (MANAGE) trial is a large international blinded randomized controlled trial of dabigatran vs placebo in patients who suffered MINS. We used a partial factorial design to also determine the effect of omeprazole vs placebo in reducing upper gastrointestinal bleeding and complications. Both study drugs were initiated in eligible patients within 35 days of suffering MINS and continued for a maximum of 2 years. The primary outcome is a composite of major vascular complications for the dabigatran trial and a composite of upper gastrointestinal complications for the omeprazole trial. We present the rationale and design of the trial and baseline characteristics of enrolled patients. The trial randomized 1754 patients between January 2013 and July 2017. Patients' mean age was 69.9 years, 51.1% were male, 14.3% had a history of peripheral artery disease, 6.6% had a history of stroke or transient ischemic attack, 12.9% had a previous myocardial infarction, and 26.0% had diabetes. The diagnosis of MINS was on the basis of an isolated ischemic troponin elevation in 80.4% of participants. MANAGE is the first randomized controlled trial to evaluate a potential treatment of patients who suffered MINS. Copyright © 2018 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Effect of cinacalcet on cardiovascular disease in patients undergoing dialysis.

PubMed

Chertow, Glenn M; Block, Geoffrey A; Correa-Rotter, Ricardo; Drüeke, Tilman B; Floege, Jürgen; Goodman, William G; Herzog, Charles A; Kubo, Yumi; London, Gerard M; Mahaffey, Kenneth W; Mix, T Christian H; Moe, Sharon M; Trotman, Marie-Louise; Wheeler, David C; Parfrey, Patrick S

2012-12-27

Disorders of mineral metabolism, including secondary hyperparathyroidism, are thought to contribute to extraskeletal (including vascular) calcification among patients with chronic kidney disease. It has been hypothesized that treatment with the calcimimetic agent cinacalcet might reduce the risk of death or nonfatal cardiovascular events in such patients. In this clinical trial, we randomly assigned 3883 patients with moderate-to-severe secondary hyperparathyroidism (median level of intact parathyroid hormone, 693 pg per milliliter [10th to 90th percentile, 363 to 1694]) who were undergoing hemodialysis to receive either cinacalcet or placebo. All patients were eligible to receive conventional therapy, including phosphate binders, vitamin D sterols, or both. The patients were followed for up to 64 months. The primary composite end point was the time until death, myocardial infarction, hospitalization for unstable angina, heart failure, or a peripheral vascular event. The primary analysis was performed on the basis of the intention-to-treat principle. The median duration of study-drug exposure was 21.2 months in the cinacalcet group, versus 17.5 months in the placebo group. The primary composite end point was reached in 938 of 1948 patients (48.2%) in the cinacalcet group and 952 of 1935 patients (49.2%) in the placebo group (relative hazard in the cinacalcet group vs. the placebo group, 0.93; 95% confidence interval, 0.85 to 1.02; P=0.11). Hypocalcemia and gastrointestinal adverse events were significantly more frequent in patients receiving cinacalcet. In an unadjusted intention-to-treat analysis, cinacalcet did not significantly reduce the risk of death or major cardiovascular events in patients with moderate-to-severe secondary hyperparathyroidism who were undergoing dialysis. (Funded by Amgen; EVOLVE ClinicalTrials.gov number, NCT00345839.).

Effect of Ezetimibe on Major Atherosclerotic Disease Events and All-Cause Mortality

PubMed Central

Hayek, Sami; Escaro, Fabrizio Canepa; Sattar, Assad; Gamalski, Steven; Wells, Karen E.; Divine, George; Ahmedani, Brian K.; Lanfear, David E.; Pladevall, Manel; Williams, L. Keoki

2012-01-01

Despite ezetimibe’s ability to reduce serum cholesterol levels, there are concerns over its vascular effects and whether it prevents or ameliorates atherosclerotic disease (AD). Our objective was to estimate the effect of ezetimibe use on major AD events and all-cause mortality and to compare these associations to those observed for hydroxy-methylglutaryl-CoA reductase inhibitor (i.e., statin) use. We identified 367 new ezetimibe users between November 1, 2002 and December 31, 2009. These individuals were ≥18 years of age and had no prior statin use. One to four statin user matches were identified for each ezetimibe user resulting in a total of 1,238 closely matched statin users. Pharmacy data and drug dosage information were used to estimate a moving window of ezetimibe and statin exposure for each day of study follow-up. The primary outcome was a composite of major AD events (coronary heart disease, cerebrovascular disease, and peripheral vascular disease events) and all-cause death. Both ezetimibe use (odds ratio [OR] 0.33, 95% CI 0.13–0.86) and statin use (OR 0.61, 95% CI 0.36–1.04) were associated with reductions in the likelihood of the composite outcome. These protective associations were most significant for cerebrovascular disease events and all-cause death. Subgroup analyses by sex, race-ethnicity, prior history of AD, diabetes status, and estimated renal function showed consistent estimates across strata with no significant differences between ezetimibe and statin use. In conclusion, ezetimibe appeared to have a protective effect on major AD events and all-cause death which was not significantly different from that observed for statin use. PMID:23219178

Peripheral vascular disease prevalence increases exponentially withproximity to roadways in an adult cardiac catherization cohort.

EPA Science Inventory

Background: Previous epidemiologic studies have suggested that residential proximity to traffic increases risk ofcardiovascular diseases (CVD) in major urban areas. Objectives: We examined the associations between mobile source air pollution and cardiovascular outcomes in a less ...

Google Maps offers a new way to evaluate claudication.

PubMed

Khambati, Husain; Boles, Kim; Jetty, Prasad

2017-05-01

Accurate determination of walking capacity is important for the clinical diagnosis and management plan for patients with peripheral arterial disease. The current "gold standard" of measurement is walking distance on a treadmill. However, treadmill testing is not always reflective of the patient's natural walking conditions, and it may not be fully accessible in every vascular clinic. The objective of this study was to determine whether Google Maps, the readily available GPS-based mapping tool, offers an accurate and accessible method of evaluating walking distances in vascular claudication patients. Patients presenting to the outpatient vascular surgery clinic between November 2013 and April 2014 at the Ottawa Hospital with vasculogenic calf, buttock, and thigh claudication symptoms were identified and prospectively enrolled in our study. Onset of claudication symptoms and maximal walking distance (MWD) were evaluated using four tools: history; Walking Impairment Questionnaire (WIQ), a validated claudication survey; Google Maps distance calculator (patients were asked to report their daily walking routes on the Google Maps-based tool runningmap.com, and walking distances were calculated accordingly); and treadmill testing for onset of symptoms and MWD, recorded in a double-blinded fashion. Fifteen patients were recruited for the study. Determination of walking distances using Google Maps proved to be more accurate than by both clinical history and WIQ, correlating highly with the gold standard of treadmill testing for both claudication onset (r = .805; P < .001) and MWD (r = .928; P < .0001). In addition, distances were generally under-reported on history and WIQ. The Google Maps tool was also efficient, with reporting times averaging below 4 minutes. For vascular claudicants with no other walking limitations, Google Maps is a promising new tool that combines the objective strengths of the treadmill test and incorporates real-world walking environments. It offers an accurate, efficient, inexpensive, and readily accessible way to assess walking distances in patients with peripheral vascular disease. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

A highly printable and biocompatible hydrogel composite for direct printing of soft and perfusable vasculature-like structures.

PubMed

Suntornnond, Ratima; Tan, Edgar Yong Sheng; An, Jia; Chua, Chee Kai

2017-12-04

Vascularization is one major obstacle in bioprinting and tissue engineering. In order to create thick tissues or organs that can function like original body parts, the presence of a perfusable vascular system is essential. However, it is challenging to bioprint a hydrogel-based three-dimensional vasculature-like structure in a single step. In this paper, we report a new hydrogel-based composite that offers impressive printability, shape integrity, and biocompatibility for 3D bioprinting of a perfusable complex vasculature-like structure. The hydrogel composite can be used on a non-liquid platform and is printable at human body temperature. Moreover, the hydrogel composite supports both cell proliferation and cell differentiation. Our results represent a potentially new vascularization strategy for 3D bioprinting and tissue engineering.

Treatment of human immunodeficiency virus-related peripheral neuropathy with Scrambler Therapy: a case report.

PubMed

Smith, Thomas J; Auwaerter, Paul; Knowlton, Amy; Saylor, Deanna; McArthur, Justin

2017-02-01

Peripheral neuropathy is one of the most common neurological complications of HIV infection with a 30-60% lifetime prevalence. Newer HIV drugs cause less peripheral neuropathy, but patients are now living long enough to develop concomitant diabetes-related, vascular-related, and chemotherapy-related neuropathy so it continues as a major debilitating issue. Recent national CDC guidelines have stressed the importance of non-opioid therapies, especially in this population that may have had drug abuse problems. We treated a 52-year-old man who had severe disabling classic peripheral neuropathy since 1998 with Scrambler Therapy (Calmare), an FDA-cleared peripheral non-invasive neuromodulation device. His pain rapidly improved, as did his motor and sensory function, with just four 45-min treatments, and he was able to come off opioids for the first time in years. When his pain returned six months later, only two treatments were needed to resolve it. This represents the first published use of this novel, inexpensive, and non-invasive pain modality in HIV peripheral neuropathy, and should engender further trials.

The vascular basement membrane in the healthy and pathological brain.

PubMed

Thomsen, Maj S; Routhe, Lisa J; Moos, Torben

2017-10-01

The vascular basement membrane contributes to the integrity of the blood-brain barrier (BBB), which is formed by brain capillary endothelial cells (BCECs). The BCECs receive support from pericytes embedded in the vascular basement membrane and from astrocyte endfeet. The vascular basement membrane forms a three-dimensional protein network predominantly composed of laminin, collagen IV, nidogen, and heparan sulfate proteoglycans that mutually support interactions between BCECs, pericytes, and astrocytes. Major changes in the molecular composition of the vascular basement membrane are observed in acute and chronic neuropathological settings. In the present review, we cover the significance of the vascular basement membrane in the healthy and pathological brain. In stroke, loss of BBB integrity is accompanied by upregulation of proteolytic enzymes and degradation of vascular basement membrane proteins. There is yet no causal relationship between expression or activity of matrix proteases and the degradation of vascular matrix proteins in vivo. In Alzheimer's disease, changes in the vascular basement membrane include accumulation of Aβ, composite changes, and thickening. The physical properties of the vascular basement membrane carry the potential of obstructing drug delivery to the brain, e.g. thickening of the basement membrane can affect drug delivery to the brain, especially the delivery of nanoparticles.

Impaired peripheral vasodilation during graded systemic hypoxia in healthy older adults: role of the sympathoadrenal system

PubMed Central

Richards, Jennifer C.; Crecelius, Anne R.; Larson, Dennis G.; Luckasen, Gary J.

2017-01-01

Systemic hypoxia is a physiological and pathophysiological stress that activates the sympathoadrenal system and, in young adults, leads to peripheral vasodilation. We tested the hypothesis that peripheral vasodilation to graded systemic hypoxia is impaired in older healthy adults and that this age-associated impairment is due to attenuated β-adrenergic mediated vasodilation and elevated α-adrenergic vasoconstriction. Forearm blood flow was measured (Doppler ultrasound), and vascular conductance (FVC) was calculated in 12 young (24 ± 1 yr) and 10 older (63 ± 2 yr) adults to determine the local dilatory responses to graded hypoxia (90, 85, and 80% O2 saturations) in control conditions, following local intra-arterial blockade of β-receptors (propranolol), and combined blockade of α- and β-receptors (phentolamine + propranolol). Under control conditions, older adults exhibited impaired vasodilation to hypoxia compared with young participants at all levels of hypoxia (peak ΔFVC at 80% SpO2 = 4 ± 6 vs. 35 ± 8%; P < 0.01). During β-blockade, older adults actively constricted at 85 and 80% SpO2 (peak ΔFVC at 80% SpO2 = −13 ± 6%; P < 0.05 vs. control), whereas the response in the young was not significantly impacted (peak ΔFVC = 28 ± 8%). Combined α- and β-blockade increased the dilatory response to hypoxia in young adults; however, older adults failed to significantly vasodilate (peak ΔFVC at 80% SpO2= 12 ± 11% vs. 58 ± 11%; P < 0.05). Our findings indicate that peripheral vasodilation to graded systemic hypoxia is significantly impaired in older adults, which cannot be fully explained by altered sympathoadrenal control of vascular tone. Thus, the impairment in hypoxic vasodilation is likely due to attenuated local vasodilatory and/or augmented vasoconstrictor signaling with age. NEW & NOTEWORTHY We found that the lack of peripheral vasodilation during graded systemic hypoxia with aging is not mediated by the sympathoadrenal system, strongly implicating local vascular control mechanisms in this impairment. Understanding these mechanisms may lead to therapeutic advances for improving tissue blood flow and oxygen delivery in aging and disease. PMID:28159810

Effects of acute and chronic cilazapril treatment in spontaneously hypertensive rats

PubMed Central

Fischli, W.; Hefti, F.; Clozel, J.-P.

1989-01-01

1 The effects of acute and chronic treatment with cilazapril, a new ACE inhibitor, on peripheral vasculature and renal excretory function were assessed in spontaneously hypertensive rats. Regional blood flow and cardiac output were measured by the radio-active microspheres technique. 2 Acute treatment (3 mg kg-1 intravenously) reduced mean arterial blood pressure from 171 ± 7 to 140 241 ± 7 mm Hg (P < 0.001), chronic treatment (1 × 10 mg kg-1 day-1 orally for 9 weeks) from 191 ± 5 to 122 ± 3 mm Hg P < 0.001). With both kinds of treatments cardiac output was unchanged. Heart rate was slightly decreased (-9%, P < 0.05) with chronic treatment. Acutely, the main effect of cilazapril was a decrease of the renal vascular resistance (-41%, P < 0.001) associated with an increase of the fraction of the cardiac output distributed to the kidney (+46%, P < 0.001). Chronically, cilazapril decreased regional vascular resistance in most of the peripheral vascular beds except the heart. 3 With a high dose of cilazapril (10 mg kg-1 orally) both acute and chronic treatment increased diuresis (+107% and +92%, P < 0.001) and natriuresis (+124% and +111%, P < 0.001) with a slight increase in kaliuresis. However, with a low dose (1 mg kg-1 orally) the kidneys responded only to chronic treatment. 4 It is concluded that chronic treatment with cilazapril decreases arterial blood pressure more than acute treatment. This effect seems to be due to a greater peripheral vasodilation. In addition, diuretic and natriuretic effects of cilazapril probably contribute to blood pressure reduction. PMID:2527529

The effects of vasoactive agents on flow through saphenous vein grafts during lower-extremity peripheral vascular surgery.

PubMed

Maslow, Andrew D; Bert, Arthur; Slaiby, Jeffrey; Carney, William; Marcaccio, Edward

2007-06-01

The purpose of this study was to assess the effects of hemodynamic alterations on vein graft flow during peripheral vascular surgery. It was hypothesized that vasopressors can be administered without compromising flow through the vein grafts. Tertiary care center, university medical center. Randomized placebo-controlled double-blinded study. The effects of phenylephrine, epinephrine, milrinone, intravenous fluid, and placebo on newly constructed peripheral vein grafts were assessed in 60 patients (12 patients in each of 5 groups). Systemic and central hemodynamics were measured by using intra-arterial and pulmonary artery catheters. Vein graft flow was measured by using a transultrasonic flow probe (Transultrasonic Inc, Ithaca, NY). Phenylephrine increased systemic mean blood pressure (mBP) (68.2-94.0 mmHg, p < 0.01), systemic vascular resistance (SVR) (1,091-1,696 dynes x sec x cm(-5), p < 0.001), and vein graft flow (39.5-58.9 mL/min, p < 0.01), whereas cardiac output remained unchanged. Epinephrine resulted in increased cardiac output (4.4-6.9 L/min, p < 0.01) and mBP (72.7-89.1 mmHg, p < 0.01), whereas vein graft flow was reduced in 6 of 12 patients. Intravenous fluid administration resulted in a relatively smaller increase in graft flow (37.6-46.0 mL/min, p < 0.05), an increase in cardiac output, and an insignificant decrease in SVR. Other treatments had either little or no effect on vein graft flow. The study hypothesis was partly supported. Although both phenylephrine and epinephrine increased blood pressure, only the former increased vein graft flow in all patients. In conjunction with increases in graft flow after fluid administration, these data suggest that factors affecting vein graft flow are not just simply related to systemic hemodynamics.

Anesthesia through an intraosseous line using an 18-gauge intravenous needle for emergency pediatric surgery.

PubMed

Hamed, Riyadh Khudeir; Hartmans, Sharon; Gausche-Hill, Marianne

2013-09-01

To describe the success and complication rate of intraosseous (IO) access for delivery of anesthesia with the use of an 18-gauge (G) intravenous (IV) needle. Prospective study. Children's Welfare Teaching Hospital, Baghdad, Iraq. 300 critically ill infants and toddlers, age 3 weeks to 16 months, requiring emergency surgery for intra-abdominal or pelvic conditions, in whom peripheral or central access was not obtainable. Patients presented for surgery between 2007 and 2010. In 26 patients, the IO catheter was established when peripheral access was not obtained at the outset of surgery; in 4 patients standard peripheral vascular access failed during the surgical procedure and IO access was obtained. An 18-G IV needle was placed into the proximal tibia and attached to an extension set with a 3-way stopcock to deliver anesthesia. For 26 critically ill children and 4 other children, IV access failed during delivery of anesthesia; vascular access was successfully obtained within minutes in all 30 infants (100%) using the intraosseous route. Ninety percent (27/30) of patients awoke immediately postoperatively in good condition; 10% (3/30) went to the pediatric intensive care unit (PICU) for further care due to their critical preoperative condition. Complications associated with use of the IO route were considered minor (3/30 pts [10%]) and included extravasation of fluid in two cases and cellulitis in one. The IO route provided for rapid delivery of anesthesia, induction, and maintenance in this series of critically ill infants undergoing emergency surgery when other vascular access routes failed. Few complications were noted. Intraosseous access was achieved through a simple technique using an 18-gauge IV needle. © 2013 Elsevier Inc. All rights reserved.

Perfusion index derived from a pulse oximeter can predict the incidence of hypotension during spinal anaesthesia for Caesarean delivery.

PubMed

Toyama, S; Kakumoto, M; Morioka, M; Matsuoka, K; Omatsu, H; Tagaito, Y; Numai, T; Shimoyama, M

2013-08-01

Hypotension during spinal anaesthesia for Caesarean delivery is a result of decreased vascular resistance due to sympathetic blockade and decreased cardiac output due to blood pooling in blocked areas of the body. Change in baseline peripheral vascular tone due to pregnancy may affect the degree of such hypotension. The perfusion index (PI) derived from a pulse oximeter has been used for assessing peripheral perfusion dynamics due to changes in peripheral vascular tone. The aim of this study was to examine whether baseline PI could predict the incidence of spinal anaesthesia-induced hypotension during Caesarean delivery. Parturients undergoing elective Caesarean delivery under spinal anaesthesia with hyperbaric bupivacaine 10 mg and fentanyl 20 μg were enrolled in this prospective study. The correlation between baseline PI and the degree of hypotension during spinal anaesthesia and also the predictability of spinal anaesthesia-induced hypotension during Caesarean delivery by PI were investigated. Baseline PI correlated with the degree of decreases in systolic and mean arterial pressure (r=0.664, P<0.0001 and r=0.491, P=0.0029, respectively). The cut-off PI value of 3.5 identified parturients at risk for spinal anaesthesia-induced hypotension with a sensitivity of 81% and a specificity of 86% (P<0.001). The change of PI in parturients with baseline PI ≤ 3.5 was not significant during the observational period, while PI in parturients with baseline PI>3.5 demonstrated marked decreases after spinal injection. We demonstrated that higher baseline PI was associated with profound hypotension and that baseline PI could predict the incidence of spinal anaesthesia-induced hypotension during Caesarean delivery.

Use of a glucose management service improves glycemic control following vascular surgery: an interrupted time-series study.

PubMed

Wallaert, Jessica B; Chaidarun, Sushela S; Basta, Danielle; King, Kathryn; Comi, Richard; Ogrinc, Greg; Nolan, Brian W; Goodney, Philip P

2015-05-01

The optimal method for obtaining good blood glucose control in noncritically ill patients undergoing peripheral vascular surgery remains a topic of debate for surgeons, endocrinologists, and others involved in the care of patients with peripheral arterial disease and diabetes. A prospective trial was performed to evaluate the impact of routine use of a glucose management service (GMS) on glycemic control within 24 hours of lower-extremity revascularization (LER). In an interrupted time-series design (May 1, 2011-April 30, 2012), surgeon-directed diabetic care (Baseline phase) to routine GMS involvement (Intervention phase) was compared following LER. GMS assumed responsibility for glucose management through discharge. The main outcome measure was glycemic control, assessed by (1) mean hospitalization glucose and (2) the percentage of recorded glucose values within target range. Statistical process control charts were used to assess the impact of the intervention. Clinically important differences in patient demographics were noted between groups; the 19 patients in the Intervention arm had worse peripheral vascular disease than the 19 patients in the Baseline arm (74% critical limb ischemia versus 58%; p = .63). Routine use of GMS significantly reduced mean hospitalization glucose (191 mg/dL Baseline versus 150 mg/dL Intervention, p < .001). Further, the proportion of glucose values in target range increased (48% Baseline versus 78% Intervention, p = .05). Following removal of GMS involvement, measures of glycemic control did not significantly decrease for the 19 postintervention patients. Routine involvement of GMS improved glycemic control in patients undergoing LER. Future work is needed to examine the impact of improved glycemic control on clinical outcomes following LER.

Intrathecal administration of a substance P receptor antagonist: studies on peripheral and central nervous system hemodynamics and on specificity of action.

PubMed

Helke, C J; Phillips, E T; O'Neill, J T

1987-07-01

Regional central nervous system and peripheral hemodynamic effects of the intrathecal (i.t.) administration of a substance P (SP) receptor antagonist, [D-Arg1, D-Pro2, D-Trp7,9, Leu11]-substance P ([D-Arg]-SP), were studied in anesthetized rats. It was found that [D-Arg]-SP (3.3 nmol i.t.) reduced mean arterial pressure and cardiac output due to a reduction in stroke volume. Total peripheral resistance was not altered. Whereas most vascular beds showed no alterations in vascular resistance, a renal vasoconstriction was noted. The hypotensive effect of [D-Arg]-SP was blocked by phentolamine (10 mg/kg i.v.) but not by propranolol (1 mg/kg i.v.). In the absence of changes in vascular arterial resistance due to [D-Arg]-SP, it appears that a change in venous return may contribute to the [D-Arg]-SP-induced reduction in stroke volume. These data provide evidence that a spinal cord SP system may tonically affect sympathetic neurons controlling venous, but not arterial, vasomotor tone. [D-Arg]-SP (i.t.) did not alter brain blood flow but significantly decreased blood flow in the thoracolumbar spinal cord 15 to 20 min after administration. The reduction in spinal cord flow did not appear to be responsible for the [D-Arg]-SP-induced hypotension because kainic acid (i.t.), an agent that interacts with glutamate receptors, produced similar pressor responses in the presence and absence of [D-Arg]-SP. In addition, whereas the pressor effect of low doses of a SP agonist [pGlu5, MePhe8, MeGly9]-substance P (5-11) were blocked by [D-Arg]-SP, a higher dose produced the typical pressor effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Silk fibroin enhances peripheral nerve regeneration by improving vascularization within nerve conduits.

PubMed

Wang, Chunyang; Jia, Yachao; Yang, Weichao; Zhang, Cheng; Zhang, Kuihua; Chai, Yimin

2018-07-01

Silk fibroin (SF)-based nerve conduits have been widely used to bridge peripheral nerve defects. Our previous study showed that nerve regeneration in a SF-blended poly (l-lactide-co-ɛ-caprolactone) [P(LLA-CL)] nerve conduit is better than that in a P(LLA-CL) conduit. However, the involved mechanisms remain unclarified. Because angiogenesis within a nerve conduit plays an important role in nerve regeneration, vascularization of SF/P(LLA-CL) and P(LLA-CL) conduits was compared both in vitro and in vivo. In the present study, we observed that SF/P(LLA-CL) nanofibers significantly promoted fibroblast proliferation, and vascular endothelial growth factor secreted by fibroblasts seeded in SF/P(LLA-CL) nanofibers was more than seven-fold higher than that in P(LLA-CL) nanofibers. Conditioned medium of fibroblasts in the SF/P(LLA-CL) group stimulated more human umbilical vein endothelial cells (HUVEC) to form capillary-like networks and promoted faster HUVEC migration. The two kinds of nerve conduits were used to bridge 10-mm-length nerve defects in rats. At 3 weeks of reparation, the blood vessel area in the SF/P(LLA-CL) group was significantly larger than that in the P(LLA-CL) group. More regenerated axons and Schwann cells were also observed in the SF/P(LLA-CL) group, which was consistent with the results of blood vessels. Collectively, our data revealed that the SF/P(LLA-CL) nerve conduit enhances peripheral nerve regeneration by improving angiogenesis within the conduit. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2070-2077, 2018. © 2018 Wiley Periodicals, Inc.

Clinical trials in peripheral vascular disease: pipeline and trial designs: an evaluation of the ClinicalTrials.gov database.

PubMed

Subherwal, Sumeet; Patel, Manesh R; Chiswell, Karen; Tidemann-Miller, Beth A; Jones, W Schuyler; Conte, Michael S; White, Christopher J; Bhatt, Deepak L; Laird, John R; Hiatt, William R; Tasneem, Asba; Califf, Robert M

2014-11-11

Tremendous advances have occurred in therapies for peripheral vascular disease (PVD); until recently, however, it has not been possible to examine the entire clinical trial portfolio of studies for the treatment of PVD (both arterial and venous disease). We examined interventional trials registered in ClinicalTrials.gov from October 2007 through September 2010 (n=40,970) and identified 676 (1.7%) PVD trials (n=493 arterial only, n=170 venous only, n=13 both arterial and venous). Most arterial studies investigated lower-extremity peripheral artery disease and acute stroke (35% and 24%, respectively), whereas most venous studies examined deep vein thrombosis/pulmonary embolus prevention (42%) or venous ulceration (25%). A placebo-controlled trial design was used in 27% of the PVD trials, and 4% of the PVD trials excluded patients >65 years of age. Enrollment in at least 1 US site decreased from 51% of trials in 2007 to 41% in 2010. Compared with noncardiology disciplines, PVD trials were more likely to be double-blinded, to investigate the use of devices and procedures, and to have industry sponsorship and assumed funding source, and they were less likely to investigate drug and behavioral therapies. Geographic access to PVD clinical trials within the United States is limited to primarily large metropolitan areas. PVD studies represent a small group of trials registered in ClinicalTrials.gov, despite the high prevalence of vascular disease in the general population. This low number, compounded by the decreasing number of PVD trials in the United States, is concerning and may limit the ability to inform current clinical practice of patients with PVD. © 2014 American Heart Association, Inc.

Arterial waves in humans during peripheral vascular surgery.

PubMed

Khir, A W; Henein, M Y; Koh, T; Das, S K; Parker, K H; Gibson, D G

2001-12-01

The purpose of this study was to investigate the effect of aortic clamping on arterial waves during peripheral vascular surgery. We measured pressure and velocity simultaneously in the ascending aorta, in ten patients (70+/-5 years) with aortic-iliac disease intra-operatively. Pressure was measured using a catheter tip manometer, and velocity was measured using Doppler ultrasound. Data were collected before aortic clamping, during aortic clamping and after unclamping. Hydraulic work in the aortic root was calculated from the measured data, the reflected waves were determined by wave-intensity analysis and wave speed was determined by the PU-loop (pressure-velocity-loop) method; a new technique based on the 'water-hammer' equation. The wave speed is approx. 32% (P<0.05) higher during clamping than before clamping. Although the peak intensity of the reflected wave does not alter with clamping, it arrives 30 ms (P<0.05) earlier and its duration is 25% (P<0.05) longer than before clamping. During clamping, left ventricule (LV) hydraulic systolic work and the energy carried by the reflected wave increased by 27% (P<0.05) and 20% (P<0.05) respectively, compared with before clamping. The higher wave speed during clamping explains the earlier arrival of the reflected waves suggesting an increase in the afterload, since the LV has to overcome earlier reflected compression waves. The longer duration of the reflected wave during clamping is associated with an increase in the total energy carried by the wave, which causes an increase in hydraulic work. Increased hydraulic work during clamping may increase LV oxygen consumption, provoke myocardial ischaemia and hence contribute to the intra-operative impairment of LV function known in patients with peripheral vascular disease.

Vitamin C prophylaxis promotes oxidative lipid damage during surgical ischemia-reperfusion.

PubMed

Bailey, Damian M; Raman, Sudarsanam; McEneny, Jane; Young, Ian S; Parham, Kelly L; Hullin, David A; Davies, Bruce; McKeeman, Gareth; McCord, Joe M; Lewis, Michael H

2006-02-15

Reactive oxygen species (ROS) have been implicated in the cellular membrane damage and postoperative morbidity associated with obligatory ischemia-reperfusion (I-R) during vascular surgery. Thus, a clinical study was undertaken to evaluate the effects of ascorbate prophylaxis on ROS exchange kinetics in 22 patients scheduled for elective abdominal aortic aneurysm (AAA) or infra-inguinal bypass (IIB) repair. Patients were assigned double-blind to receive intravenous sodium ascorbate (2 g vitamin C, n=10) or placebo (0.9% saline, n=12) administered 2 h prior to surgery. Blood samples were obtained from the arterial and venous circulation proximal to the respective sites of surgical repair (local) and from an antecubital vein (peripheral) during cross-clamping (ischemia) and within 60 s of clamp release (reperfusion). Ascorbate supplementation increased the venoarterial concentration difference (v-adiff) of lipid hydroperoxides (LH), interleukin (IL)-6 and vascular endothelial growth factor (VEGF) protein during ischemia. This increased the peripheral concentration of LH, total creatine phosphokinase (CPK), and VEGF protein during reperfusion (P<0.05 vs placebo). Electron paramagnetic resonance (EPR) spectroscopy confirmed that free iron was available for oxidative catalysis in the local ischemic venous blood of supplemented patients. An increased concentration of the ascorbate radical (A.-) and alpha-phenyl-tert-butylnitrone (PBN) adducts assigned as lipid-derived alkoxyl (LO.) and alkyl (LC.) species were also detected in the peripheral blood of supplemented patients during reperfusion (P<0.05 vs ischemia). In conclusion, these findings suggest that ascorbate prophylaxis may have promoted iron-induced oxidative lipid damage via a Fenton-type reaction initiated during the ischemic phase of surgery. The subsequent release of LH into the systemic circulation may have catalyzed formation of second-generation radicals implicated in the regulation of vascular permeability and angiogenesis.

Mitochondrial DNA damage and vascular function in patients with diabetes mellitus and atherosclerotic cardiovascular disease.

PubMed

Fetterman, Jessica L; Holbrook, Monica; Westbrook, David G; Brown, Jamelle A; Feeley, Kyle P; Bretón-Romero, Rosa; Linder, Erika A; Berk, Brittany D; Weisbrod, Robert M; Widlansky, Michael E; Gokce, Noyan; Ballinger, Scott W; Hamburg, Naomi M

2016-03-31

Prior studies demonstrate mitochondrial dysfunction with increased reactive oxygen species generation in peripheral blood mononuclear cells in diabetes mellitus. Oxidative stress-mediated damage to mitochondrial DNA promotes atherosclerosis in animal models. Thus, we evaluated the relation of mitochondrial DNA damage in peripheral blood mononuclear cells s with vascular function in patients with diabetes mellitus and with atherosclerotic cardiovascular disease. We assessed non-invasive vascular function and mitochondrial DNA damage in 275 patients (age 57 ± 9 years, 60 % women) with atherosclerotic cardiovascular disease alone (N = 55), diabetes mellitus alone (N = 74), combined atherosclerotic cardiovascular disease and diabetes mellitus (N = 48), and controls age >45 without diabetes mellitus or atherosclerotic cardiovascular disease (N = 98). Mitochondrial DNA damage measured by quantitative PCR in peripheral blood mononuclear cells was higher with clinical atherosclerosis alone (0.55 ± 0.65), diabetes mellitus alone (0.65 ± 1.0), and combined clinical atherosclerosis and diabetes mellitus (0.89 ± 1.32) as compared to control subjects (0.23 ± 0.64, P < 0.0001). In multivariable models adjusting for age, sex, and relevant cardiovascular risk factors, clinical atherosclerosis and diabetes mellitus remained associated with higher mitochondrial DNA damage levels (β = 0.14 ± 0.13, P = 0.04 and β = 0.21 ± 0.13, P = 0.002, respectively). Higher mitochondrial DNA damage was associated with higher baseline pulse amplitude, a measure of arterial pulsatility, but not with flow-mediated dilation or hyperemic response, measures of vasodilator function. We found greater mitochondrial DNA damage in patients with diabetes mellitus and clinical atherosclerosis. The association of mitochondrial DNA damage and baseline pulse amplitude may suggest a link between mitochondrial dysfunction and excessive small artery pulsatility with potentially adverse microvascular impact.

Frequency spectrum analysis of finger photoplethysmographic waveform variability during haemodialysis.

PubMed

Javed, Faizan; Middleton, Paul M; Malouf, Philip; Chan, Gregory S H; Savkin, Andrey V; Lovell, Nigel H; Steel, Elizabeth; Mackie, James

2010-09-01

This study investigates the peripheral circulatory and autonomic response to volume withdrawal in haemodialysis based on spectral analysis of photoplethysmographic waveform variability (PPGV). Frequency spectrum analysis was performed on the baseline and pulse amplitude variabilities of the finger infrared photoplethysmographic (PPG) waveform and on heart rate variability extracted from the ECG signal collected from 18 kidney failure patients undergoing haemodialysis. Spectral powers were calculated from the low frequency (LF, 0.04-0.145 Hz) and high frequency (HF, 0.145-0.45 Hz) bands. In eight stable fluid overloaded patients (fluid removal of >2 L) not on alpha blockers, progressive reduction in relative blood volume during haemodialysis resulted in significant increase in LF and HF powers of PPG baseline and amplitude variability (P < 0.01), when expressed in mean-scaled units. The augmentation of LF powers in PPGV during haemodialysis may indicate the recovery and possibly further enhancement of peripheral sympathetic vascular modulation subsequent to volume unloading, whilst the increase in respiratory HF power in PPGV is most likely a sign of preload reduction. Spectral analysis of finger PPGV may provide valuable information on the autonomic vascular response to blood volume reduction in haemodialysis, and can be potentially utilized as a non-invasive tool for assessing peripheral circulatory control during routine dialysis procedure.

Pyridostigmine prevents peripheral vascular endothelial dysfunction in rats with myocardial infarction.

PubMed

Qin, Fangfang; Lu, Yi; He, Xi; Zhao, Ming; Bi, Xueyuan; Yu, Xiaojiang; Liu, Jinjun; Zang, Weijin

2014-03-01

1. Myocardial infarction (MI) is characterized by the withdrawal of vagal activity and increased sympathetic activity. We have shown previously that pyridostigmine (PYR), an acetylcholinesterase inhibitor, was able to improve vagal activity and ameliorate cardiac dysfunction following MI. However, the effect of PYR on endothelial dysfunction in peripheral arteries after MI remains unclear. 2. In the present study, MI was induced by coronary artery ligation in adult Sprague-Dawley rats. Rats were treated intragastrically with saline or PYR (approximately 31 mg/kg per day) for 2 weeks, at which time haemodynamic and parasympathetic parameters and the vascular reactivity of isolated mesenteric arteries were measured and the ultrastructure of the endothelium evaluated. 3. Compared with the MI group, PYR not only improved cardiac function, vagal nerve activity and endothelial impairment, but also reduced intravascular superoxide anion and malondialdehyde. In addition, in the PYR-treated MI group, nitric oxide (NO) bioavailability was increased and attenuated endothelium-dependent relaxations were improved, whereas restored vasodilator responses were inhibited by N(G)-nitro-L-arginine methyl ester. 4. Based on our results, PYR is able to attenuate the impairment of peripheral endothelial function and maintain endothelial ultrastructural integrity in MI rats by inhibiting reactive oxygen species production, enhancing NO bioavailability and improving vagal activity. © 2014 Wiley Publishing Asia Pty Ltd.

Audible handheld Doppler ultrasound determines reliable and inexpensive exclusion of significant peripheral arterial disease.

PubMed

Alavi, Afsaneh; Sibbald, R Gary; Nabavizadeh, Reza; Valaei, Farnaz; Coutts, Pat; Mayer, Dieter

2015-12-01

To determine the accuracy of audible arterial foot signals with an audible handheld Doppler ultrasound for identification of significant peripheral arterial disease as a simple, quick, and readily available bedside screening tool. Two hundred consecutive patients referred to an interprofessional wound care clinic underwent audible handheld Doppler ultrasound of both legs. As a control and comparator, a formal bilateral lower leg vascular study including the calculation of Ankle Brachial Pressure Index and toe pressure (TP) was performed at the vascular lab. Diagnostic reliability of audible handheld Doppler ultrasound was calculated versus Ankle Brachial Pressure Index as the gold standard test. A sensitivity of 42.8%, a specificity of 97.5%, negative predictive value of 94.10%, positive predictive value of 65.22%, positive likelihood ratio of 17.52, and negative likelihood ratio of 0.59. The univariable logistic regression model had an area under the curve of 0.78. There was a statistically significant difference at the 5% level between univariable and multivariable area under the curves of the dorsalis pedis and posterior tibial models (p < 0.001). Audible handheld Doppler ultrasound proved to be a reliable, simple, rapid, and inexpensive bedside exclusion test of peripheral arterial disease in diabetic and nondiabetic patients. © The Author(s) 2015.

Development of a Regenerative Peripheral Nerve Interface for Control of a Neuroprosthetic Limb

PubMed Central

Frost, Christopher M.; Martin, David C.; Larkin, Lisa M.

2016-01-01

Background. The purpose of this experiment was to develop a peripheral nerve interface using cultured myoblasts within a scaffold to provide a biologically stable interface while providing signal amplification for neuroprosthetic control and preventing neuroma formation. Methods. A Regenerative Peripheral Nerve Interface (RPNI) composed of a scaffold and cultured myoblasts was implanted on the end of a divided peroneal nerve in rats (n = 25). The scaffold material consisted of either silicone mesh, acellular muscle, or acellular muscle with chemically polymerized poly(3,4-ethylenedioxythiophene) conductive polymer. Average implantation time was 93 days. Electrophysiological tests were performed at endpoint to determine RPNI viability and ability to transduce neural signals. Tissue samples were examined using both light microscopy and immunohistochemistry. Results. All implanted RPNIs, regardless of scaffold type, remained viable and displayed robust vascularity. Electromyographic activity and stimulated compound muscle action potentials were successfully recorded from all RPNIs. Physiologic efferent motor action potentials were detected from RPNIs in response to sensory foot stimulation. Histology and transmission electron microscopy revealed mature muscle fibers, axonal regeneration without neuroma formation, neovascularization, and synaptogenesis. Desmin staining confirmed the preservation and maturation of myoblasts within the RPNIs. Conclusions. RPNI demonstrates significant myoblast maturation, innervation, and vascularization without neuroma formation. PMID:27294122

Peripheral arterial disease in a female using high-dose combined oral contraceptive pills.

PubMed

Pallavee, P; Samal, Sunita; Samal, Rupal

2013-01-01

The association between oral contraceptive (OC) pills and vascular diseases is well-known, although, the present generation of pills is considered to be relatively safer in this regard. Hormonal treatment for severe abnormal uterine bleeding is usually considered after ruling out malignancy, when such bleeding is resistant to all other forms of treatment. We report a case of severe peripheral arterial disease in a female, who had been on high-dose OC pills for an extended period of time for severe uterine bleeding.

LUMBAR SYMPATHECTOMY BY ELECTROCOAGULATION—Its Use in the Management of Certain Vascular and Visceral Disorders

PubMed Central

Raney, R. B.; Raney, Aidan A.; Silver, Harrison E.

1954-01-01

Although normally the sympathetic nerves aid vascular dilatation during effort, in certain diseases of the vascular system they have a reverse effect. Abolition of sympathetic vasoconstrictive impulses by sympathectomy is the most effective treatment in some chronic peripheral vascular conditions. The authors have used electrocoagulation for a number of years and found it quick, effective and more likely to prevent regeneration of the affected nerves. Improvement was obtained by sympathectomy in arteriosclerotic vascular insufficiency, thromboangiitis obliterans, Raynaud's disease, reflex sympathetic dystrophy following thrombophlebitis or trauma, scleroderma, spinal sympathetic dystrophy and acquired megacolon. A case of causalgia was aggravated by the operation. Abstention from the use of tobacco appears to be sufficient for control of symptoms in many cases. Since vasospasm is manifested in many conditions long before a thrombotic catastrophe occurs, not only relief of symptoms but prevention of irreversible changes may be achieved by early operation. ImagesFigure 1.Figure 2. PMID:13116029

Evaluation of the Effects of Acupuncture on Blood Flow in Humans with Ultrasound Color Doppler Imaging

PubMed Central

Takayama, Shin; Watanabe, Masashi; Kusuyama, Hiroko; Nagase, Satoru; Seki, Takashi; Nakazawa, Toru; Yaegashi, Nobuo

2012-01-01

Color Doppler imaging (CDI) can be used to noninvasively create images of human blood vessels and quantitatively evaluate blood flow in real-time. The purpose of this study was to assess the effects of acupuncture on the blood flow of the peripheral, mesenteric, and retrobulbar arteries by CDI. Statistical significance was defined as P values less than 0.05. Blood flow in the radial and brachial arteries was significantly lower during needle stimulation on LR3 than before in healthy volunteers, but was significantly higher after needle stimulation than before. LR3 stimulation also resulted in a significant decrease in the vascular resistance of the short posterior ciliary artery and no significant change of blood flow through the superior mesenteric artery (SMA) during acupuncture. In contrast, ST36 stimulation resulted in a significant increase in blood flow through the SMA and no significant change in the vascular resistance of the retrobulbar arteries. Additionally, acupuncture at previously determined acupoints in patients with open-angle glaucoma led to a significant reduction in the vascular resistance of the central retinal artery and short posterior ciliary artery. Our results suggest that acupuncture can affect blood flow of the peripheral, mesenteric, and retrobulbar arteries, and CDI can be useful to evaluate hemodynamic changes by acupuncture. PMID:22778772

NEURONAL ACTION ON THE DEVELOPING BLOOD VESSEL PATTERN

PubMed Central

James, Jennifer M.; Mukouyama, Yoh-suke

2011-01-01

The nervous system relies on a highly specialized network of blood vessels for development and neuronal survival. Recent evidence suggests that both the central and peripheral nervous systems (CNS and PNS) employ multiple mechanisms to shape the vascular tree to meet its specific metabolic demands, such as promoting nerve-artery alignment in the PNS or the development the blood brain barrier in the CNS. In this article we discuss how the nervous system directly influences blood vessel patterning resulting in neuro-vascular congruence that is maintained throughout development and in the adult. PMID:21978864

Addition of autologous mesenchymal stem cells to whole blood for bioenhanced ACL repair has no benefit in the porcine model.

PubMed

Proffen, Benedikt L; Vavken, Patrick; Haslauer, Carla M; Fleming, Braden C; Harris, Chad E; Machan, Jason T; Murray, Martha M

2015-02-01

Coculture of mesenchymal stem cells (MSCs) from the retropatellar fat pad and peripheral blood has been shown to stimulate anterior cruciate ligament (ACL) fibroblast proliferation and collagen production in vitro. Current techniques of bioenhanced ACL repair in animal studies involve adding a biologic scaffold, in this case an extracellular matrix-based scaffold saturated with autologous whole blood, to a simple suture repair of the ligament. Whether the enrichment of whole blood with MSCs would further improve the in vivo results of bioenhanced ACL repair was investigated. The addition of MSCs derived from adipose tissue or peripheral blood to the blood-extracellular matrix composite, which is used in bioenhanced ACL repair to stimulate healing, would improve the biomechanical properties of a bioenhanced ACL repair after 15 weeks of healing. Controlled laboratory study. Twenty-four adolescent Yucatan mini-pigs underwent ACL transection followed by (1) bioenhanced ACL repair, (2) bioenhanced ACL repair with the addition of autologous adipose-derived MSCs, and (3) bioenhanced ACL repair with the addition of autologous peripheral blood derived MSCs. After 15 weeks of healing, the structural properties of the ACL (yield load, failure load, and linear stiffness) were measured. Cell and vascular density were measured in the repaired ACL via histology, and its tissue structure was qualitatively evaluated using the advanced Ligament Maturity Index. After 15 weeks of healing, there were no significant improvements in the biomechanical or histological properties with the addition of adipose-derived MSCs. The only significant change with the addition of peripheral blood MSCs was an increase in knee anteroposterior laxity when measured at 30° of flexion. These findings suggest that the addition of adipose or peripheral blood MSCs to whole blood before saturation of an extracellular matrix carrier with the blood did not improve the functional results of bioenhanced ACL repair after 15 weeks of healing in the pig model. Whole blood represents a practical biologic additive to ligament repair, and any other additive (including stem cells) should be demonstrated to be superior to this baseline before clinical use is considered. © 2014 The Author(s).

Safety of Aerobic Exercise in People With Diabetic Peripheral Neuropathy: Single-Group Clinical Trial

PubMed Central

Pasnoor, Mamatha; Singh, Rupali; D'Silva, Linda J.; Yoo, Min; Billinger, Sandra A.; LeMaster, Joseph W.; Dimachkie, Mazen M.; Herbelin, Laura; Wright, Douglas E.

2015-01-01

Background Exercise is recommended for people with diabetes, but little is known about exercise in people with diabetic peripheral neuropathy (DPN). Objective The primary purpose of this preliminary study was to examine adverse events (AEs) during moderate-intensity, supervised aerobic exercise in people with DPN. The secondary purpose was to examine changes in fatigue, aerobic fitness, and other outcomes after intervention. Design This was a single-group preliminary study. Setting The setting was an academic medical center. Participants Participants were 18 people who were sedentary and had type 2 diabetes and peripheral neuropathy (mean age=58.1 years, SD=5). Intervention The intervention was a supervised 16-week aerobic exercise program (3 times per week at 50% to >70% oxygen uptake reserve). Measurements Adverse events were categorized as related or unrelated to the study, anticipated or unanticipated, and serious or not serious. Outcomes included fatigue (Multidimensional Fatigue Inventory), cardiovascular fitness (peak oxygen uptake), body composition (dual-energy x-ray absorptiometry), sleep quality, plasma metabolic markers, and peripheral vascular function. Results During the study, 57 nonserious AEs occurred. Improvements were found in general fatigue (mean change=−3.5; 95% confidence interval [95% CI]=−1.3, −5.3), physical fatigue (mean change=−3.1; 95% CI=−1.2, −5.0), peak oxygen uptake (mean change=1.1 mL·kg−1·min−1; 95% CI=0.2, 1.9), total body fat (mean change=−1%; 95% CI=−0.3, −1.7), fat mass (mean change=−1,780 g; 95% CI=−616.2, −2,938.7), and peripheral blood flow (mean change=2.27%; 95% CI=0.6, 4.0). Limitations This was a small-scale, uncontrolled study. A future randomized controlled trial is needed to fully assess the effects of exercise on the outcomes. Conclusions This study provides new support for supervised aerobic exercise in people with DPN. However, it is important for physical therapists to carefully prescribe initial exercise intensity and provide close monitoring and education to address the anticipated AEs as people who are sedentary and have DPN begin an exercise program. PMID:25278335

Evacetrapib and Cardiovascular Outcomes in High-Risk Vascular Disease.

PubMed

Lincoff, A Michael; Nicholls, Stephen J; Riesmeyer, Jeffrey S; Barter, Philip J; Brewer, H Bryan; Fox, Keith A A; Gibson, C Michael; Granger, Christopher; Menon, Venu; Montalescot, Gilles; Rader, Daniel; Tall, Alan R; McErlean, Ellen; Wolski, Kathy; Ruotolo, Giacomo; Vangerow, Burkhard; Weerakkody, Govinda; Goodman, Shaun G; Conde, Diego; McGuire, Darren K; Nicolau, Jose C; Leiva-Pons, Jose L; Pesant, Yves; Li, Weimin; Kandath, David; Kouz, Simon; Tahirkheli, Naeem; Mason, Denise; Nissen, Steven E

2017-05-18

The cholesteryl ester transfer protein inhibitor evacetrapib substantially raises the high-density lipoprotein (HDL) cholesterol level, reduces the low-density lipoprotein (LDL) cholesterol level, and enhances cellular cholesterol efflux capacity. We sought to determine the effect of evacetrapib on major adverse cardiovascular outcomes in patients with high-risk vascular disease. In a multicenter, randomized, double-blind, placebo-controlled phase 3 trial, we enrolled 12,092 patients who had at least one of the following conditions: an acute coronary syndrome within the previous 30 to 365 days, cerebrovascular atherosclerotic disease, peripheral vascular arterial disease, or diabetes mellitus with coronary artery disease. Patients were randomly assigned to receive either evacetrapib at a dose of 130 mg or matching placebo, administered daily, in addition to standard medical therapy. The primary efficacy end point was the first occurrence of any component of the composite of death from cardiovascular causes, myocardial infarction, stroke, coronary revascularization, or hospitalization for unstable angina. At 3 months, a 31.1% decrease in the mean LDL cholesterol level was observed with evacetrapib versus a 6.0% increase with placebo, and a 133.2% increase in the mean HDL cholesterol level was seen with evacetrapib versus a 1.6% increase with placebo. After 1363 of the planned 1670 primary end-point events had occurred, the data and safety monitoring board recommended that the trial be terminated early because of a lack of efficacy. After a median of 26 months of evacetrapib or placebo, a primary end-point event occurred in 12.9% of the patients in the evacetrapib group and in 12.8% of those in the placebo group (hazard ratio, 1.01; 95% confidence interval, 0.91 to 1.11; P=0.91). Although the cholesteryl ester transfer protein inhibitor evacetrapib had favorable effects on established lipid biomarkers, treatment with evacetrapib did not result in a lower rate of cardiovascular events than placebo among patients with high-risk vascular disease. (Funded by Eli Lilly; ACCELERATE ClinicalTrials.gov number, NCT01687998 .).

Composite vascular scaffold combining electrospun fibers and physically-crosslinked hydrogel with copper wire-induced grooves structure.

PubMed

Liu, Yuanyuan; Jiang, Chen; Li, Shuai; Hu, Qingxi

2016-08-01

While the field of tissue engineered vascular grafts has greatly advanced, many inadequacies still exist. Successfully developed scaffolds require mechanical and structural properties that match native vessels and optimal microenvironments that foster cell integration, adhesion and growth. We have developed a small diameter, three-layered composite vascular scaffold which consists of electrospun fibers and physically-crosslinked hydrogel with copper wire-induced grooves by combining the electrospinning and dip-coating methods. Scaffold morphology and mechanics were assessed, quantified and compared to native vessels. Scaffolds were seeded with Human Umbilical Vein Endothelial Cells (HUVECs), cultured in vitro for 3 days and were evaluated for cell viability and morphology. The results showed that composite scaffolds had adjustable mechanical strength and favorable biocompatibility, which is important in the future clinical application of Tissue-engineered vascular grafts (TEVGs). Copyright © 2016 Elsevier Ltd. All rights reserved.

Overview of classification systems in peripheral artery disease.

PubMed

Hardman, Rulon L; Jazaeri, Omid; Yi, J; Smith, M; Gupta, Rajan

2014-12-01

Peripheral artery disease (PAD), secondary to atherosclerotic disease, is currently the leading cause of morbidity and mortality in the western world. While PAD is common, it is estimated that the majority of patients with PAD are undiagnosed and undertreated. The challenge to the treatment of PAD is to accurately diagnose the symptoms and determine treatment for each patient. The varied presentations of peripheral vascular disease have led to numerous classification schemes throughout the literature. Consistent grading of patients leads to both objective criteria for treating patients and a baseline for clinical follow-up. Reproducible classification systems are also important in clinical trials and when comparing medical, surgical, and endovascular treatment paradigms. This article reviews the various classification systems for PAD and advantages to each system.

Peripherally derived FGF21 promotes remyelination in the central nervous system

PubMed Central

Kuroda, Mariko; Maedera, Noriko; Koyama, Yoshihisa; Hamaguchi, Machika; Fujimura, Harutoshi; Konishi, Morichika; Itoh, Nobuyuki; Mochizuki, Hideki

2017-01-01

Demyelination in the central nervous system (CNS) leads to severe neurological deficits that can be partially reversed by spontaneous remyelination. Because the CNS is isolated from the peripheral milieu by the blood-brain barrier, remyelination is thought to be controlled by the CNS microenvironment. However, in this work we found that factors derived from peripheral tissue leak into the CNS after injury and promote remyelination in a murine model of toxin-induced demyelination. Mechanistically, leakage of circulating fibroblast growth factor 21 (FGF21), which is predominantly expressed by the pancreas, drives proliferation of oligodendrocyte precursor cells (OPCs) through interactions with β-klotho, an essential coreceptor of FGF21. We further confirmed that human OPCs expressed β-klotho and proliferated in response to FGF21 in vitro. Vascular barrier disruption is a common feature of many CNS disorders; thus, our findings reveal a potentially important role for the peripheral milieu in promoting CNS regeneration. PMID:28825598

Some Non-FDA Approved Uses for Neuromodulation: A Review of the Evidence.

PubMed

Lee, Samuel; Abd-Elsayed, Alaa

2016-09-01

Neuromodulation, including spinal cord stimulation and peripheral nerve field stimulation, has been used with success in treating several painful conditions. The FDA approved the use of neuromodulation for a few indications. We review evidence for neuromodulation in treating some important painful conditions that are not currently FDA approved. This review included an online web search for only clinical trials testing the efficacy of neuromodulation in treating coronary artery disease, peripheral vascular disease (PVD), headache, and peripheral field stimulation. Our systematic literature search found 10, 6, and 3 controlled studies relating to coronary artery disease, PVD, and headache, respectively. Our review also included 5 noncontrolled studies relating to peripheral field stimulation, as no controlled studies had been completed. This review article shows compelling evidence based on clinical trials that neuromodulation can be of benefit for patients with serious painful conditions that are not currently approved by the FDA. © 2015 World Institute of Pain.

Identification of local angiogenic and inflammatory markers in the menstrual blood of women with endometriosis.

PubMed

da Silva, Cláudia Maria; Vilaça Belo, Andrezza; Passos Andrade, Sílvia; Peixoto Campos, Paula; Cristina França Ferreira, Márcia; Lopes da Silva-Filho, Agnaldo; Mendonça Carneiro, Márcia

2014-09-01

The aim of this study was to evaluate the presence of myeloperoxidase (MPO), N-acetyl-β-D-glucosaminidase (NAG), tumor necrosis factor alpha (TNF-α) and vascular endothelial growth factor (VEGF) in peripheral and menstrual blood in women with (n=10) and without (n=7) endometriosis. NAG and MPO activities were evaluated by enzymatic methods, whereas TNF-α and VEGF by immunoassay. No significant differences were found for these markers, neither in menstrual nor in peripheral blood between groups. Menstrual blood NAG (P=0.039) and MPO (P=0.0117) activities in the endometriosis group were significantly higher than in peripheral blood. NAG and MPO presented positive linear correlation in peripheral (P=0.07; r=0.641) and menstrual blood (P=0.01; r=0.603). These findings point to the existence of an increased local inflammatory activity in women with endometriosis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Digital gangrene associated with anticentromere antibodies.

PubMed

Grace, Mary; Varada; Dhanesh, Es

2014-03-01

Anticentromere antibodies have been associated with peripheral vascular occlusive disease, but then it is mostly accompanied by sclerodactyly in the context of a connective tissue disorder. We report a case of digital gangrene in a 75 year old lady with no other associations except positive anticentromere antibodies.

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

PubMed Central

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

2015-01-01

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. PMID:26543345

The Impact and Implication of Peripheral Vascular Leakage on Ultra-Widefield Fluorescein Angiography in Uveitis.

PubMed

Thomas, Akshay S; Redd, Travis; Campbell, John P; Palejwala, Neal V; Baynham, Justin T; Suhler, Eric B; Rosenbaum, James T; Lin, Phoebe

2017-10-16

To study if peripheral vascular leakage (PVL) on ultra-widefield fluorescein angiography (UWFFA) prognosticates complications of uveitis or necessitates treatment augmentation. Retrospective cohort study of uveitis patients imaged with UWFFA and ≥1 yr of follow-up. We included 73 eyes of 42 patients with uveitis. There was no difference in baseline, intermediate, final visual acuity (p = 0.47-0.95) or rates of cystoid macular edema (CME) (p = 0.37-0.87) in eyes with PVL vs. those without. Eyes with PVL receiving baseline treatment augmentation were more likely to have baseline CME but were not more likely to have impaired visual acuity at final follow-up. PVL was independently associated with treatment augmentation on generalized estimating equation analysis with multivariable linear regression (OR: 4.39, p = 0.015). PVL did not confer an increased risk of impaired VA or CME at ≥1 yr follow-up but was possibly an independent driver of treatment augmentation.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, V., E-mail: vmiller@coe.drexel.edu; Lin, A.; Brettschneider, J.

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 themore » 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.« less

Expression of very low density lipoprotein receptor mRNA in circulating human monocytes: its up-regulation by hypoxia.

PubMed

Nakazato, K; Ishibashi, T; Nagata, K; Seino, Y; Wada, Y; Sakamoto, T; Matsuoka, R; Teramoto, T; Sekimata, M; Homma, Y; Maruyama, Y

2001-04-01

Although very low density lipoprotein (VLDL) receptor expression by macrophages has been shown in the vascular wall, it is not clear whether or not circulating monocytes express the VLDL receptor. We investigated the expression of VLDL receptor mRNA in human peripheral blood monocytes and monocyte-derived macrophages by reverse transcriptase polymerase chain reaction (RT-PCR) and nucleotide sequencing after subcloning of PCR product. VLDL receptor mRNA was detected both in peripheral blood monocytes and monocyte-derived macrophages. Expression of VLDL receptor mRNA was upregulated by hypoxia in monocytes, whereas treatment with oxidized LDL, interleukin-1beta or monocyte chemoattractant protein-1 did not affect the levels of VLDL receptor mRNA in monocytes and macrophages. The present study shows a novel response of VLDL receptor mRNA to hypoxia, suggesting a role for VLDL receptor in the metabolism of lipoproteins in the vascular wall and the development of atherosclerosis.

VESGEN Software for Mapping and Quantification of Vascular Regulators

NASA Technical Reports Server (NTRS)

Parsons-Wingerter, Patricia A.; Vickerman, Mary B.; Keith, Patricia A.

2012-01-01

VESsel GENeration (VESGEN) Analysis is an automated software that maps and quantifies effects of vascular regulators on vascular morphology by analyzing important vessel parameters. Quantification parameters include vessel diameter, length, branch points, density, and fractal dimension. For vascular trees, measurements are reported as dependent functions of vessel branching generation. VESGEN maps and quantifies vascular morphological events according to fractal-based vascular branching generation. It also relies on careful imaging of branching and networked vascular form. It was developed as a plug-in for ImageJ (National Institutes of Health, USA). VESGEN uses image-processing concepts of 8-neighbor pixel connectivity, skeleton, and distance map to analyze 2D, black-and-white (binary) images of vascular trees, networks, and tree-network composites. VESGEN maps typically 5 to 12 (or more) generations of vascular branching, starting from a single parent vessel. These generations are tracked and measured for critical vascular parameters that include vessel diameter, length, density and number, and tortuosity per branching generation. The effects of vascular therapeutics and regulators on vascular morphology and branching tested in human clinical or laboratory animal experimental studies are quantified by comparing vascular parameters with control groups. VESGEN provides a user interface to both guide and allow control over the users vascular analysis process. An option is provided to select a morphological tissue type of vascular trees, network or tree-network composites, which determines the general collections of algorithms, intermediate images, and output images and measurements that will be produced.

Hematopoietic Stem Cell Capture and Directional Differentiation into Vascular Endothelial Cells for Metal Stent-Coated Chitosan/Hyaluronic Acid Loading CD133 Antibody

PubMed Central

Zhang, Fan; Feng, Bo; Fan, Qingyu; Yang, Feng; Shang, Debin; Sui, Jinghan; Zhao, Hong

2015-01-01

A series of metal stents coated with chitosan/hyaluronic acid (CS/HA) loading antibodies by electrostatic self-assembled method were prepared, and the types of cells captured by antibodies and their differentiation in vascular endothelial cells (ECs) evaluated by molecular biology and scanning electron microscope. The results showed that CD133 stent can selectively capture hematopoietic stem cells (HSC),which directionally differentiate into vascular ECs in peripheral blood by (CS/HA) induction, and simultaneously inhibit migration and proliferation of immune cells and vascular smooth muscle cells (MCs). CD34 stent can capture HSC, hematopoietic progenitor cells that differentiate into vascular ECs and immune cells, promoting smooth MCs growth, leading to thrombosis, inflammation, and rejection. CD133 stent can be implanted into miniature pig heart coronary and can repair vascular damage by capturing own HSC, thus contributing to the rapid natural vascular repair, avoiding inflammation and rejection, thrombosis and restenosis. These studies demonstrated that CD133 stent of HSC capture will be an ideal coated metal stent providing a new therapeutic approach for cardiovascular and cerebrovascular disease. PMID:25404533

Effects of nitroglycerin and nitroprusside on vascular capacitance of anesthetized ganglion-blocked dogs.

PubMed

Ogilvie, R I; Zborowska-Sluis, D

1991-10-01

To determine whether changes in vascular capacitance induced by nitroglycerin (NTG) and nitroprusside were due to changes in compliance or unstressed vascular volume, doses producing similar reductions in arterial pressure (Psa) were studied on separate days in six dogs anesthetized and ventilated with pentobarbital after splenectomy during ganglion blockade with hexamethonium. Mean circulatory filling pressure (Pmcf) was determined during transient circulatory arrest induced by acetylcholine at baseline blood volumes and after increases of 5 and 10 ml/kg. Central blood volumes (CBVs, pulmonary artery to aortic root) were determined from transit times, and separately measured cardiac output (CO) was estimated by thermodilution (right atrium to pulmonary artery). NTG and nitroprusside produced similar reductions in Psa and Pmcf without significantly altering right atrial pressure (Pra), pressure gradient for venous return, or CO. Total vascular compliance was not altered, but total vascular capacitance was increased on an average of 4.0 +/- 1.4 ml/kg after NTG and 3.0 +/- 1.3 ml/kg after nitroprusside by increases in unstressed volume. Both drugs caused a variable reduction in CBV, averaging 2 ml/kg. Thus, both drugs produced a large increase in peripheral venous capacitance by increasing unstressed vascular volume without altering total vascular compliance.

Vascular tissue engineering: the next generation.

PubMed

Cleary, Muriel A; Geiger, Erik; Grady, Conor; Best, Cameron; Naito, Yuji; Breuer, Christopher

2012-07-01

It is the ultimate goal of tissue engineering: an autologous tissue engineered vascular graft (TEVG) that is immunologically compatible, nonthrombogenic, and can grow and remodel. Currently, native vessels are the preferred vascular conduit for procedures such as coronary artery bypass (CABG) or peripheral bypass surgery. However, in many cases these are damaged, have already been harvested, or are simply unusable. The use of synthetic conduits is severely limited in smaller diameter vessels due to increased incidence of thrombosis, infection, and graft failure. Current research has therefore energetically pursued the development of a TEVG that can incorporate into a patient's circulatory system, mimic the vasoreactivity and biomechanics of the native vasculature, and maintain long-term patency. Copyright © 2012. Published by Elsevier Ltd.

Quantifying the vascular response to ischemia with speckle variance optical coherence tomography

PubMed Central

Poole, Kristin M.; McCormack, Devin R.; Patil, Chetan A.; Duvall, Craig L.; Skala, Melissa C.

2014-01-01

Longitudinal monitoring techniques for preclinical models of vascular remodeling are critical to the development of new therapies for pathological conditions such as ischemia and cancer. In models of skeletal muscle ischemia in particular, there is a lack of quantitative, non-invasive and long term assessment of vessel morphology. Here, we have applied speckle variance optical coherence tomography (OCT) methods to quantitatively assess vascular remodeling and growth in a mouse model of peripheral arterial disease. This approach was validated on two different mouse strains known to have disparate rates and abilities of recovering following induction of hind limb ischemia. These results establish the potential for speckle variance OCT as a tool for quantitative, preclinical screening of pro- and anti-angiogenic therapies. PMID:25574425

Clinical impact of exercise in patients with peripheral arterial disease.

PubMed

Novakovic, Marko; Jug, Borut; Lenasi, Helena

2017-08-01

Increasing prevalence, high morbidity and mortality, and decreased health-related quality of life are hallmarks of peripheral arterial disease. About one-third of peripheral arterial disease patients have intermittent claudication with deleterious effects on everyday activities, such as walking. Exercise training improves peripheral arterial disease symptoms and is recommended as first line therapy for peripheral arterial disease. This review examines the effects of exercise training beyond improvements in walking distance, namely on vascular function, parameters of inflammation, activated hemostasis and oxidative stress, and quality of life. Exercise training not only increases walking distance and physiologic parameters in patients with peripheral arterial disease, but also improves the cardiovascular risk profile by helping patients achieve better control of hypertension, hyperglycemia, obesity and dyslipidemia, thus further reducing cardiovascular risk and the prevalence of coexistent atherosclerotic diseases. American guidelines suggest supervised exercise training, performed for a minimum of 30-45 min, at least three times per week, for at least 12 weeks. Walking is the most studied exercise modality and its efficacy in improving cardiovascular parameters in patients with peripheral arterial disease has been extensively proven. As studies have shown that supervised exercise training improves walking performance, cardiovascular parameters and quality of life in patients with peripheral arterial disease, it should be encouraged and more often prescribed.

The heart, macrocirculation and microcirculation in hypertension: a unifying hypothesis.

PubMed

Struijker Boudier, Harry A J; Cohuet, Géraldine M S; Baumann, Marcus; Safar, Michel E

2003-06-01

Epidemiological studies in the past decade have stressed the importance of both pulse pressure and mean arterial pressure (MAP) as important risk factors in hypertension-related cardiovascular disease. Pulse pressure and MAP are determined by different segments of the cardiovascular system. Pulse pressure is the pulsatile component of the blood pressure curve. It is determined by left ventricular ejection, the cushioning capacity (compliance) of the large arteries, and the timing and intensity of wave reflections from the microcirculation. MAP is the steady component; it is determined by cardiac output and peripheral (micro)vascular resistance. To a large degree, the structural design of the heart and vascular tree determine the pulse pressure and MAP, in addition to the propagation of the pressure wave through the vasculature. Pressure and flow, in contrast, influence the composition and geometry of the heart and vasculature. Hypertensive disease is associated with important structural alterations of the heart, such as hypertrophy and fibrosis, and of the vasculature, such as large artery stiffening, small artery remodelling and microvascular rarefaction. Recent basic research has revealed some of the molecular pathways involved in the remodelling of the cardiovascular system under the influence of physical forces. For correct understanding of the pathophysiology of hypertensive disease, its risks for target-organ damage and its effective treatment, both the pulsatile and steady components of the blood pressure curve must be considered.

Semiquantitative analysis of atherosclerotic plaque using optical coherence tomography and time-of-flight secondary ion mass spectrometry

NASA Astrophysics Data System (ADS)

Korol, Renee M.; Togonu-Bickersteth, Babajide; Yang, Victor X.; Dimov, Stamen; Vatsya, Pracha; Gordon, Maggie; Vitkin, Alex; Liu, Liying; Canham, Peter; Clarke, Sharon; Lucas, Alexandra

2003-10-01

Atherosclerosis is the underlying vascular pathology that initiates arterial thromboembolic occlusions (myocardial infarctions, strokes and peripheral vessel blockage). Two imaging modalities, Optical Coherence Tomography (OCT) and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS), were investigated for detection and compositional analysis of unstable plaque associated with plaque erosion and sudden occlusion. OCT produces high resolution images whereas mass spectrometry images provide information on the spatial distribution of chemical elements. Diseased carotid arteries taken from patients with high-risk lesions were imaged with OCT and ToF-SIMS to give molecular and metabolic information, and matched with histopathology. OCT results show clear indications of vascular remodeling by the presence of fatty acid deposits, fibrous tissue and calcifications. ToF-SIMS further characterized changes based on secondary ion topography analysis where a high 23Na/39K ratio was indicative of arterial tissue degradation and the amount of 40Ca corresponded with late stage atherosclerosis. This pilot experiment has demonstrated that in vitro OCT imaging and ToF-SIMS of diseased carotid arteries have scientific merit for targeting clinically relevant morphology and metabolic changes to compare stable and unstable plaque. These optical techniques provide complimentary metabolic and molecular information on unstable plaque, specifically cell break-down with altered ion ratios of 23Na, 39K and 40Ca.

Low-carbohydrate, high-protein, high-fat diet alters small peripheral artery reactivity in metabolic syndrome patients.

PubMed

Merino, Jordi; Kones, Richard; Ferré, Raimon; Plana, Núria; Girona, Josefa; Aragonés, Gemma; Ibarretxe, Daiana; Heras, Mercedes; Masana, Luis

2014-01-01

Low carbohydrate diets have become increasingly popular for weight loss. Although they may improve some metabolic markers, particularly in type 2 diabetes mellitus (T2D) or metabolic syndrome (MS), their net effect on vascular function remains unclear. Evaluate the relation between dietary macronutrient composition and the small artery reactive hyperaemia index (saRHI), a marker of small artery vascular function, in a cohort of MS patients. This cross-sectional study included 160 MS patients. Diet was evaluated by a 3-day food-intake register and reduced to a novel low-carbohydrate diet score (LCDS). Physical examination, demographic, biochemical and anthropometry parameters were recorded, and saRHI was measured in each patient. Individuals in the lowest LCDS quartile (Q1; 45% carbohydrate, 19% protein, 31% fat) had higher saRHI values than those in the top quartile (Q4; 30% carbohydrate, 25% protein, 43% fat) (1.84±0.42 vs. 1.55±0.25, P=.012). These results were similar in T2D patients (Q1=1.779±0.311 vs. Q4=1.618±0.352, P=.011) and also in all of the MS components, except for low HDLc. Multivariate analysis demonstrated that individuals in the highest LCDS quartile, that is, consuming less carbohydrates, had a significantly negative coefficient of saRHI which was independent of confounders (HR: -0.747; 95%CI: 0.201, 0.882; P=.029). These data suggest that a dietary pattern characterized by a low amount of carbohydrate, but reciprocally higher amounts of fat and protein, is associated with poorer vascular reactivity in patients with MS and T2D. Copyright © 2013 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

Profile of Cardiovascular Risk Factors and Mortality in Patients with Symptomatic Peripheral Arterial Disease

PubMed Central

Zanati, Silméia Garcia; Mouraria, Guilherme Grisi; Matsubara, Luiz Shigero; Giannini, Mariângela; Matsubara, Beatriz B

2009-01-01

INTRODUCTION: The present study examines cardiovascular risk factor profiles and 24-month mortality in patients with symptomatic peripheral arterial disease. DESIGN STUDY: Prospective observational study including 75 consecutive patients with PAD (67 ± 9.7 years of age; 52 men and 23 women) hospitalized for planned peripheral vascular reconstruction. Doppler echocardiograms were performed before surgery in 54 cases. Univariate analyses were performed using Student’s t-test or Fisher’s exact test. Survival analysis at 24-month follow-up was performed using the Cox regression model and Kaplan-Meier method including age and chronic use of aspirin as covariates. Survival curves were compared using the log-rank test. RESULTS: Hypertension and smoking were the most frequent risk factors (52 cases and 51 cases, respectively), followed by diabetes (32 cases). Undertreated dyslipidemia was found in 26 cases. Fasting glycine levels (131 ± 69.1 mg/dl) were elevated in 29 cases. Myocardial hypertrophy was found in 18 out of 54 patients. Thirty-four patients had been treated with aspirin. Overall mortality over 24 months was 24% and was associated with age (HR: 0.064; CI95: 0.014–0.115; p=0.013) and lack of use of aspirin, as no deaths occurred among those using this drug (p<0.001). No association was found between cardiovascular death (11 cases) and the other risk factors. CONCLUSION: There is a high prevalence of uncontrolled (treated or untreated) cardiovascular risk factors in patients undergoing planned peripheral vascular reconstruction, and chronic use of aspirin is associated with reduced all-cause mortality in these patients. PMID:19488590

Comparison of TR Band™ and VasoStat™ Hemostasis Devices following Transpedal Catheterization for Lower Extremity Revascularization for Peripheral Arterial Disease.

PubMed

Kwan, Tak W; Patel, Apurva; Parikh, Roosha; Auguste, Uschi; Rosero, Hugo; Huang, Yili; Liou, Michael; Ratcliffe, Justin; Puma, Joseph

2016-08-01

Transpedal access is increasingly utilized for peripheral vascular catheterization. There is a paucity of data on the use of radial hemostasis devices as an alternative to manual compression for achievement of hemostasis after this approach. To compare safety and efficacy of two hemostasis devices following transpedal catheterization for lower extremity revascularization for peripheral arterial disease. A consecutive cohort of patients with bilateral Rutherford 2-5 disease who underwent transpedal catheterization for peripheral vascular interventions were retrospectively analyzed. In each patient, retrograde tibial artery access was obtained, a 4 French sheath was placed, and all revascularization was performed via tibial access. In all patients, a TR Band™ (Terumo Medical, n = 215) and/or VasoStat™ (Forge Medical, n = 99) were used to apply puncture site compression, following removal of the tibial sheath until hemostasis was achieved. Safety and efficacy of each device was compared. Puncture site hemostasis was achieved in all patients within 2 hours of sheath removal facilitating early discharge. Two access site pseudoaneurysms occurred within 30 days of revascularization, one of which followed TR Band™ placement and the other following VasoStat™ placement (P = 0.53). Each patient was successfully treated with ultrasound-guided thrombin injection. Loss of access site patency by duplex ultrasound occurred in 2 patients following the TR Band™ and a single patient following the VasoStat™ (P = 1.0). Both the TR Band™ and the VasoStat™ were effective in achieving hemostasis following transpedal catheterization with low rates of complications. © 2016, Wiley Periodicals, Inc.

HCV RNA Genomic sequences and HCV-E2 glycoprotein in sural nerve biopsies from HCV-infected patients with peripheral neuropathy.

PubMed

Russi, S; Sansonno, D; Monaco, S; Mariotto, S; Ferrari, S; Pavone, F; Lauletta, G; Dammacco, F

2018-06-01

Peripheral neuropathy (PN), the major neurological complication of chronic HCV infection, is frequently associated with mixed cryoglobulinaemia (MC) and small-vessel systemic vasculitis. While humoral and cell-mediated immune mechanisms are suspected to act together in an aberrant immune response that results in peripheral nerve damage, the role of HCV remains largely speculative. The possible demonstration of HCV in peripheral nerve tissue would obviously assume important pathogenic implications. We studied sural nerve biopsies from 11 HCV-positive patients with neuropathic symptoms: five with and six without MC. In situ hybridization (ISH) and immunofluorescence studies were carried out to detect genomic and antigenomic HCV RNA sequences and HCV-encoded E2-glycoprotein, respectively. Epineurial vascular deposits of E2-glycoprotein were found in four (80%) MC and in two (33.3%) non-MC patients, respectively. These findings were enhanced by the perivascular deposition of positive-, though not negative-strand replicative RNA, as also found in the nerve extracts of all patients. Mild inflammatory cell infiltrates with no deposits of immunoglobulins and/or complement proteins were revealed around small vessels, without distinct vasculitis changes between MC and non-MC patients. These results indicate that nerve vascular HCV RNA/E2 deposits associated to perivascular inflammatory infiltrates were similar in chronically HCV-infected patients, regardless of cryoglobulin occurrence. Given the failure to demonstrate HCV productive infection in the examined sural nerve biopsies, nerve damage is likely to result from virus-triggered immune-mediated mechanisms. © 2017 British Neuropathological Society.

Peripheral Vascular Disease

MedlinePlus

... smokers aged 20 to 40. Smoking causes the blood vessels to tighten in everyone who smokes. But in people with Buerger’s disease, there is so much tightening in the vessels that a lack of oxygen to the cells (ischemia) or tissue death (necrosis) may result. The symptoms may be different for ...

Impact of weight loss on ankle-brachial index and interartery blood pressures

USDA-ARS?s Scientific Manuscript database

Objective: To assess whether weight loss improves markers of peripheral artery disease and vascular stenosis. Methods: The Action for Health in Diabetes randomized clinical trial compared intensive lifestyle intervention (ILI) for weight loss to a control condition of diabetes support and education...

Impact of meal fatty acid composition on postprandial lipaemia, vascular function and blood pressure in postmenopausal women.

PubMed

Rathnayake, Kumari M; Weech, Michelle; Jackson, Kim G; Lovegrove, Julie A

2018-03-16

CVD are the leading cause of death in women globally, with ageing associated with progressive endothelial dysfunction and increased CVD risk. Natural menopause is characterised by raised non-fasting TAG concentrations and impairment of vascular function compared with premenopausal women. However, the mechanisms underlying the increased CVD risk after women have transitioned through the menopause are unclear. Dietary fat is an important modifiable risk factor relating to both postprandial lipaemia and vascular reactivity. Meals rich in SFA and MUFA are often associated with greater postprandial TAG responses compared with those containing n-6 PUFA, but studies comparing their effects on vascular function during the postprandial phase are limited, particularly in postmenopausal women. The present review aimed to evaluate the acute effects of test meals rich in SFA, MUFA and n-6 PUFA on postprandial lipaemia, vascular reactivity and other CVD risk factors in postmenopausal women. The systematic search of the literature identified 778 publications. The impact of fat-rich meals on postprandial lipaemia was reported in seven relevant studies, of which meal fat composition was compared in one study described in three papers. An additional study determined the impact of a high-fat meal on vascular reactivity. Although moderately consistent evidence suggests detrimental effects of high-fat meals on postprandial lipaemia in postmenopausal (than premenopausal) women, there is insufficient evidence to establish the impact of meals of differing fat composition. Furthermore, there is no robust evidence to conclude the effect of meal fatty acids on vascular function or blood pressure. In conclusion, there is an urgent requirement for suitably powered robust randomised controlled trials to investigate the impact of meal fat composition on postprandial novel and established CVD risk markers in postmenopausal women, an understudied population at increased cardiometabolic risk.

On the role of vasopressin and angiotensin in the development of irreversible haemorrhagic shock

PubMed Central

Errington, M. L.; e Silva, M. Rocha

1974-01-01

1. Long-lasting haemorrhagic hypotension (4·5 hr at 35 mmHg) leading to irreversible haemorrhagic shock, has been studied in normal dogs, in dogs treated with a bradykinin potentiating nonapeptide (BPP9a), which blocks the conversion of angiotensin I to angiotensin II, and in dogs with experimental chronic diabetes insipidus (DI dogs). BPP9a was given by I.V. injection before the start of bleeding (BPP pre-treated group), 45 min after blood pressure had reached 35 mmHg (BPP early treated group) or 2 hr after blood pressure had reached 35 mmHg (BPP late-treated group). After retransfusion of blood all dogs were allowed to recover and observed for a further period of 3 days. 2. Untreated control dogs developed haemorrhagic shock with tachycardia, low cardiac output, low total peripheral conductance and low stroke volume. All died within 24 hr of retransfusion, with pathological lesions typical of irreversible haemorrhagic shock. 3. BPP pre-treated dogs developed haemorrhagic shock with bradycardia (during early shock), high cardiac output, high peripheral vascular conductance and high stroke volume when compared with the untreated controls. All pre-treated animals survived the 3 day observation period. They were then killed and on post-mortem showed no signs of irreversible haemorrhagic shock. 4. BPP early-treated animals behaved like controls before BPP, but like pre-treated animals after the drug. Only one out of eight died within the 3 day observation period. 5. BPP late-treated dogs behaved like controls before BPP. They responded to the drug with a rise in cardiac output, peripheral vascular conductance and stroke volume, and with a fall in heart rate. These responses were, however, short-lived. Four out of these eight animals died within the 3 day observation period, with lesions of irreversible haemorrhagic shock. 6. DI dogs developed haemorrhagic shock with tachycardia (like controls), but with high cardiac output and peripheral vascular conductance (like BPP pre-treated dogs). The stroke volume of DI dogs was intermediate between those of controls and pre-treated groups. All six dogs survived the 3 day observation period. 7. BPP9a had no measurable effect on the course of endotoxic shock. 8. It is suggested that the normally severe vasoconstriction of the mesenteric vascular bed, which is thought to be responsible for irreversible haemorrhagic shock, is absent or attenuated in the absence of vasopressin or angiotensin. The consequences of this on the development of irreversibility are discussed. PMID:4373570

[Sonoelastography, B-mode sonography, and color Doppler sonography findings of pleomorphic adenomas and Warthin tumors of parotid gland].

PubMed

Yerli, Hasan; Eşki, Erkan

2015-01-01

This study aims to investigate the sonoelastography (SE), B-mode sonography, and color Doppler sonography findings of the pleomorphic adenomas and Warthin tumors of the parotid gland. A total of 84 parotid masses (23 pleomorphic adenomas, 25 Warthin tumors) in 72 patients (37 males, 35 females; mean age 59 years; range 30 to 79 years) were retrospectively analyzed. For each lesion, B-mode sonography, color Doppler sonography, and SE images were evaluated. Vascularity and elasticity scores of the tumors during color Doppler sonography and SE examinations were calculated by 4-scoring method. Lobulated contour and cystic areas were more common in the pleomorphic adenomas and Warthin tumors during the B-mode sonography examination (p<0.05). Peripheral vascularity was common in more than half of the pleomorphic adenoma patients, whereas central or mixed vascularity was seen in a large group of the Warthin tumor patients (p<0.05). The mean scores on color Doppler sonography examination were 1.13±0.81 for pleomorphic adenomas and 1.96±0.97 for Warthin tumors (p<0.05). The mean scores on SE examination were 2.69±0.70 for pleomorphic adenomas and 1.83±0.63 for Warthin tumors (p<0.05). Score 1 on SE examination was found in three of five Warthin tumor patients with peripheral vascularity on color Doppler sonography. B-mode, color Doppler and elastography examinations by sonography provide some helpful findings in the differentiation of pleomorphic adenomas and Warthin tumors.

Marrow-isolated adult multilineage inducible cells embedded within a biologically-inspired construct promote recovery in a mouse model of peripheral vascular disease.

PubMed

Grau-Monge, Cristina; Delcroix, Gaëtan J-R; Bonnin-Marquez, Andrea; Valdes, Mike; Awadallah, Ead Lewis Mazen; Quevedo, Daniel F; Armour, Maxime R; Montero, Ramon B; Schiller, Paul C; Andreopoulos, Fotios M; D'Ippolito, Gianluca

2017-02-17

Peripheral vascular disease is one of the major vascular complications in individuals suffering from diabetes and in the elderly that is associated with significant burden in terms of morbidity and mortality. Stem cell therapy is being tested as an attractive alternative to traditional surgery to prevent and treat this disorder. The goal of this study was to enhance the protective and reparative potential of marrow-isolated adult multilineage inducible (MIAMI) cells by incorporating them within a bio-inspired construct (BIC) made of two layers of gelatin B electrospun nanofibers. We hypothesized that the BIC would enhance MIAMI cell survival and engraftment, ultimately leading to a better functional recovery of the injured limb in our mouse model of critical limb ischemia compared to MIAMI cells used alone. Our study demonstrated that MIAMI cell-seeded BIC resulted in a wide range of positive outcomes with an almost full recovery of blood flow in the injured limb, thereby limiting the extent of ischemia and necrosis. Functional recovery was also the greatest when MIAMI cells were combined with BICs, compared to MIAMI cells alone or BICs in the absence of cells. Histology was performed 28 days after grafting the animals to explore the mechanisms at the source of these positive outcomes. We observed that our critical limb ischemia model induces an extensive loss of muscular fibers that are replaced by intermuscular adipose tissue (IMAT), together with a highly disorganized vascular structure. The use of MIAMI cells-seeded BIC prevented IMAT infiltration with some clear evidence of muscular fibers regeneration.

MIAMI cells embedded within a biologically-inspired construct promote recovery in a mouse model of peripheral vascular disease

PubMed Central

Grau-Monge, Cristina; Delcroix, Gaëtan J.-R; Bonnin-Marquez, Andrea; Valdes, Mike; Awadallah, Ead Lewis Mazen; Quevedo, Daniel F.; Armour, Maxime R.; Montero, Ramon B.; Schiller, Paul C.; Andreopoulos, Fotios M.; D’Ippolito, Gianluca

2017-01-01

Peripheral vascular disease is one of the major vascular complications in individuals suffering from diabetes and in the elderly that is associated with significant burden in terms of morbidity and mortality. Stem cell therapy is being tested as an attractive alternative to traditional surgery to prevent and treat this disorder. The goal of this study was to enhance the protective and reparative potential of marrow-isolated adult multilineage inducible (MIAMI) cells by incorporating them within a bio-inspired construct (BIC) made of 2 layers of gelatin B electrospun nanofibers. We hypothesized that the BIC would enhance MIAMI cell survival and engraftment, ultimately leading to a better functional recovery of the injured limb in our mouse model of critical limb ischemia compared to MIAMI cells used alone. Our study demonstrated that MIAMI cell-seeded BIC resulted in a wide range of positive outcomes with an almost full recovery of blood flow in the injured limb, thereby limiting the extent of ischemia and necrosis. Functional recovery was also the greatest when MIAMI cells were combined with BICs, compared to MIAMI cells alone or BICs in the absence of cells. Histology was performed 28 days after grafting the animals to explore the mechanisms at the source of these positive outcomes. We observed that our critical limb ischemia model induces an extensive loss of muscular fibers that are replaced by intermuscular adipose tissue (IMAT), together with a highly disorganized vascular structure. The use of MIAMI cells-seeded BIC prevented IMAT infiltration with some clear evidence of muscular fibers regeneration. PMID:28211362

Differential impact of diabetes mellitus type II and arterial hypertension on collateral artery growth and concomitant macrophage accumulation.

PubMed

Ito, Wulf D; Lund, Natalie; Sager, Hendrik; Becker, Wiebke; Wenzel, Ulrich

2015-01-01

Diabetes mellitus type II and arterial hypertension are major risk factors for peripheral arterial disease and have been considered to reduce collateral growth (arteriogenesis). Collateral growth proceeds through different stages. Vascular proliferation and macrophage accumulation are hallmarks of early collateral growth. We here compare the impact of arterial hypertension and diabetes mellitus type II on collateral proliferation (Brdu incorporation) and macrophage accumulation (ED 2 staining) as well as collateral vessel function (collateral conductance) in a rat model of peripheral vascular disease (femoral artery occlusion), diabetes mellitus type II (Zucker fatty diabetic rats and Zucker lean rat controls) and arterial hypertension (induced via clip placement around the right renal arteriy). We furthermore tested the impact of monocyte chemoattractant protein-1 (MCP‑1) on collateral proliferation and macrophage accumulation in these models Diabetic animals showed reduced vascular proliferation and macrophage accumulation, which however did not translate into a change of collateral conductance. Hypertensive animals on the contrary had reduced collateral conductances without altered macrophage accumulation and only a marginal reduction in collateral proliferation. Infusion of MCP‑1 only enhanced vascular proliferation in diabetic animals. These findings illustrate that impaired monocyte/macrophage recruitment is responsible for reduced collateral growth under diabetic conditions but not in arterial hypertension suggesting that diabetes mellitus in particular affects early stages of collateral growth whereas hypertension has its impact on later remodeling stages. Successful pro-arteriogenic treatment strategies in a patient population that presents with diabetes mellitus and arterial hypertension need to address different stages of collateral growth and thus different molecular and cellular targets simultaneously.

Could an endoneurial endothelial crosstalk between Wnt/β-catenin and Sonic Hedgehog pathways underlie the early disruption of the infra-orbital blood-nerve barrier following chronic constriction injury?

PubMed

Moreau, Nathan; Mauborgne, Annie; Couraud, Pierre-Olivier; Romero, Ignacio A; Weksler, Babette B; Villanueva, Luis; Pohl, Michel; Boucher, Yves

2017-01-01

Blood–nerve barrier disruption is pivotal in the development of neuroinflammation, peripheral sensitization, and neuropathic pain after peripheral nerve injury. Activation of toll-like receptor 4 and inactivation of Sonic Hedgehog signaling pathways within the endoneurial endothelial cells are key events, resulting in the infiltration of harmful molecules and immunocytes within the nerve parenchyma. However, we showed in a previous study that preemptive inactivation of toll-like receptor 4 signaling or sustained activation of Sonic Hedgehog signaling did not prevent the local alterations observed following peripheral nerve injury, suggesting the implication of another signaling pathway. Using a classical neuropathic pain model, the infraorbital nerve chronic constriction injury (IoN-CCI), we investigated the role of the Wnt/β-catenin pathway in chronic constriction injury-mediated blood–nerve barrier disruption and in its interactions with the toll-like receptor 4 and Sonic Hedgehog pathways. In the IoN-CCI model versus control, mRNA expression levels and/or immunochemical detection of major Wnt/Sonic Hedgehog pathway (Frizzled-7, vascular endothelial-cadherin, Patched-1 and Gli-1) and/or tight junction proteins (Claudin-1, Claudin-5, and Occludin) readouts were assessed. Vascular permeability was assessed by sodium fluorescein extravasation. IoN-CCI induced early alterations in the vascular endothelial-cadherin/β-catenin/Frizzled-7 complex, shown to participate in local blood–nerve barrier disruption via a β-catenin-dependent tight junction protein downregulation. Wnt pathway also mediated a crosstalk between toll-like receptor 4 and Sonic Hedgehog signaling within endoneurial endothelial cells. Nevertheless, preemptive inhibition of Wnt/β-catenin signaling before IoN-CCI could not prevent the downregulation of key Sonic Hedgehog pathway readouts or the disruption of the infraorbital blood–nerve barrier, suggesting that Sonic Hedgehog pathway inhibition observed following IoN-CCI is an independent event responsible for blood–nerve barrier disruption. A crosstalk between Wnt/β-catenin- and Sonic Hedgehog-mediated signaling pathways within endoneurial endothelial cells could mediate the chronic disruption of the blood–nerve barrier following IoN-CCI, resulting in increased irreversible endoneurial vascular permeability and neuropathic pain development.

Clinical application of laser treatment for cardiovascular surgery

PubMed Central

Okada, Masayoshi; Yoshida, Masato; Tsuji, Yoshihiko; Horii, Hiroyuki

2011-01-01

Background: Recently, several kinds of lasers have been widely employed in the field of medicine and surgery. However, laser applications are very rare in the field of cardiovascular surgery throughout the world. So, we have experimentally tried to use lasers in the field of cardiovascular surgery. There were three categories: 1) Transmyocardial laser revascularization (TMLR), 2) Laser vascular anastomosis, and 3) Laser angioplasty in the peripheral arterial diseases. By the way, surgery for ischemic heart disease has been widely performed in Japan. Especially coronary artery bypass grafting (CABG) for these patients has been done as a popular surgical method. Among these patients there are a few cases for whom CABG and percutaneous coronary intervention (PCI) could not be carried out, because of diffuse stenosis and small caliber of coronary arteries. Materials and methods of TMLR: A new method of tranasmyocardial revascularization by CO2 laser (output 100 W, irradiation time 0.2 sec) was experimentally performed to save severely ill patients. In this study, a feasibility of transmyocardial laser revascularization from left ventricular cavity through artificially created channels by laser was precisely evaluated. Results: In trials on dogs laser holes 0.2mm in diameter have been shown microscopically to be patent even 3 years after their creation, thus this procedure could be used as a new method of transmyocardial laser revascularization. Clinical application of TMLR: Subsequently, transmyocardial laser revascularization was employed in a 55-year-old male patient with severe angina pectoris who had undergone pericardiectomy 7 years before. He was completely recovered from severe chest pain. Conclusions of TMLR: This patient was the first successful case in the world with TMLR alone. This method might be done for the patients who percutaneous coronary intervention and coronary artery bypass grafting could be carried out. Laser vascular anastomosis: At present time, in vascular surgery there are some problems to keep long-term patency after anastomosis of the conventional suture method, especially for small-caliber vessels. Materials and methods of Laser vascular anastomosis: From these standpoints, a low energy CO2 laser was employed experimentally in vascular anastomosis for small-caliber vessels. Resullts of Laser vascular anastomosis: From preliminary experiments it could be concluded that the optimal laser output was 20–40 mW and irradiation time was 6–12 sec/mm for vascular anastomosis of small-caliber vessels in the extremities. And then, histologic findings and intensity of the laser anastomotic sites were investigated thereafter. Subseqently, good enough intensity and good healing of laser anastomotic sites as well as the conventional suture method could be observed. There were no statistic differences between laser and suture methods. A feasibility of laser anastomosis could be considered and clinical application could be recognized. Clinical applications of Laser vascular anastomosis: On February 21, 1985, arterio-venous laser anastomosis for the patient with renal failure was smoothly done and she could accept hemodialysis. Conclusions of Laser vascular anastomosis: This patient was the first clinical successful case in the world. Thereafter, Laser vascular anastomosis were in 111 patients with intermittent claudication, refractory crural ulcer, and coronary disorders. Thereafter, they are going well. Laser angioplasty: Laser angioplasty for peripheral arterial diseases. There are many methods to treat peripheral arterial diseases such as balloon method, atherectomy, laser technique and stenting graft in the field of endovascular treatment. Recent years, minimal invasive treatment should be employed even in the surgical treatment. However, there are different images between these methods. Materials and methods of Laser angioplasty: We have chosen to use laser for endovascular treatment for peripheral arterial diseases. We have tried to check between laser energy and vessel wall. Results of Laser angioplasty: Subsequently, it could be concluded that optimal conditions for laser angioplasty were 6 W in output and irradiation time was 5 sec. And with another method of feedback control system, temperature of metal tip probe was 200°C and irradiation time was 5 sec for each shot. And histological study and feasibility of angioscopic guidance could be done and clinical application was started. Until now, 115 patients were successfully treated with their life longevity. Conclusions of Laser angioplasty: Thus, laser applications were useful methods to treat a lot of patients with some ischemic problems. PMID:24155531

Scanning electron microscopy observation of vascularization around hydroxyapatite using vascular corrosion casts.

PubMed

Chang, C S; Su, C Y; Lin, T C

1999-01-01

An intimate relationship exists between the regenerative response of the vascular and osseous elements following hydroxyapatite (HA) implantation. In order to fully comprehend the 3-dimensional vascular architecture around HA, dense HA particles were implanted into the tibiae of dogs. Following healing periods of 2 weeks, 1 month, and 3 months, the tibiae were prepared by the corrosion cast technique. Under scanning electron microscopy (SEM) observation, the characteristic vascular morphology of the HA-implanted cavity was successfully demonstrated. The initial vascularization began in the form of loose sinusoidal capillaries. Many sinusoids formed a complex network by anastomosing with each other. The newly formed vessels extended centripetally from the peripheral cavity wall and from the periosteal surface. Under greater magnification, the tapered vascular sprouting was shown to project into the space that was previously occupied by an HA particle. The presence of vascular sprouting is clearly an important indicator of angiogenesis. Increasing vascularization was demonstrated with time. The presence of vessels in the Haversian's canal indicated the more established vascularization. Almost full vascularization of the HA-implanted cavity was seen 3 months after implantation. The vascular organizational layout of the cavity was also clearly shown in the fractured transverse-sectioned sample. In the control without HA implantation, the central region of the cavity showed a hollow pattern in the initial stage. The vascularization looked like it was collapsing and not fully filling the cavity. However, remarkable differences of the final vascular pattern could not be found between the study and control group after 3-month implantation. The study provides the time-lapsed 3-dimensional vascular changes of the HA-implanted cavity, as well as the value of the corrosion cast technique in examining the bony circulation. Copyright 1999 John Wiley & Sons, Inc.

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…

EFFECT OF ARSENICALS ON CELL CYCLE DISTRIBUTION AND EXPRESSION OF CELL CYCLE PROTEINS IN HUMAN PRIMARY KERATINOCYTES

EPA Science Inventory

Environmental exposure to arsenic is a major public health concern. Epidemiological studies have demonstrated a strong correlation between levels of arsenic in drinking water and incidence of cancers of skin, lung, bladder and peripheral and cerebro vascular diseases. Despite eno...

Physiological measures and mental-state assessment

NASA Technical Reports Server (NTRS)

Stern, John A.

1988-01-01

General considerations regarding monitoring of operators for alertness are discussed, including who should be monitored and what information should be collected. Measures that have been used to ascertain more general and persistent states of alertness are outlined, including cardiac activity, peripheral vascular activity, skin conductance, electroencephalography, pupillography, oculomotor activity, and body movements.

The use of shock waves in peripheral nerve regeneration: new perspectives?

PubMed

Hausner, Thomas; Nógrádi, Antal

2013-01-01

Low-energy extracorporeal shock wave treatment (ESWT) is a relatively new therapeutic tool that is widely used for the treatment of epicondylitis and plantar fasciitis and to foster bone and wound healing. Shock waves, sonic pulses with high energy impact, are thought to induce biochemical changes within the targeted tissues through mechanotransduction. The biological effects of ESWT are manifested in improved vascularization, the local release of growth factors, and local anti-inflammatory effects, but the target cells too are influenced. ESWT appears to have differential effects on peripheral nerves and has been proved to promote axonal regeneration after axotomy. This review discusses the effects of ESWT on intact and injured peripheral nerves and suggests a multiple mechanism of action. © 2013 Elsevier Inc. All rights reserved.

Subclavian Artery Pseudoaneurysm in an Unusual Case of Digital Gangrene.

PubMed

Majhi, Bhuban; Pal, Nandita

2017-01-01

A young male patient presented at a tertiary care hospital with cold and bluish left upper limb accompanied with digital gangrene arousing suspicion of peripheral vascular disease. History did not reveal any high-risk behavior. Clinical examination and subsequent investigations lead to the diagnosis of acute infective endocarditis of native aortic valve along with peripheral embolism caused by methicillin-resistant Staphylococcus aureus . Fogarty's balloon embolectomy was done following which patient developed pseudoaneurysm of the left subclavian artery. These iatrogenic sequelae were managed with the resection of the pseudoaneurysm and prolonged antibiotic therapy as per the culture and sensitivity report.

Cytocompatibility and biologic characteristics of synthetic scaffold materials of rabbit acellular vascular matrix combining with human-like collagen I.

PubMed

Liu, Xuqian; Wang, Jie; Dong, Fusheng; Song, Peng; Tian, Songbo; Li, Hexiang; Hou, Yali

2017-10-01

Scaffold material provides a three-dimensional growing environment for seed cells in the research field of tissue engineering. In the present study, rabbit arterial blood vessel cells were chemically removed with trypsin and Triton X-100 to prepare rabbit acellular vascular matrix scaffold material. Observation by He&Masson staining revealed that no cellular components or nuclei existed in the vascular intima and media after decellularization. Human-like collagen I was combined with acellular vascular matrix by freeze-drying to prepare an acellular vascular matrix-0.25% human-like collagen I scaffold to compensate for the extracellular matrix loss during the decellularization process. We next performed a series of experiments to test the water absorbing quality, biomechanics, pressure resistance, cytotoxicity, and ultra-micro structure of the acellular vascular matrix composite material and natural rabbit artery and found that the acellular vascular matrix-0.25% human-like collagen I material behaved similarly to natural rabbit artery. In conclusion, the acellular vascular matrix-0.25% human-like collagen I composite material provides a new approach and lays the foundation for novel scaffold material research into tissue engineering of blood vessels.

Importance of the splanchnic vascular bed in human blood pressure regulation.

NASA Technical Reports Server (NTRS)

Rowell, L. B.; Detry, J.-M. R.; Blackmon, J. R.; Wyss, C.

1972-01-01

Three-part experiment in which five subjects were exposed to lower body negative pressure (LBNP) at -50 mm Hg below the iliac crests. Duration of LBNP to earliest vagal symptoms was 7 to 21 min; all data are expressed as changes from control period to the last measurements before these symptoms. In part I, forearm blood flow (by Whitney gauge) fell 45% during LBNP. In part II, splanchnic blood flow (from arterial clearance hepatic extraction of indocyanine green) fell 32% and splanchnic vascular resistance rose 30%. In part III, cardiac output fell 28%, stroke volume 51%, and central blood volume 21%. Total peripheral resistance and heart rate rose 19% and 52%. Of the reduction in total vascular conductance, decreased splanchnic conductance accounted for approximately 33%; skin plus muscle conductance decreased similarly.

Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange

PubMed Central

Porter, William Ruger; Witmer, Lawrence M.

2015-01-01

Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature, as well as pathways that would bypass neurosensory tissues. The orbital region houses a large venous sinus that receives cooled blood from the nasal region. Blood vessels from the nasal region and orbital sinus show anastomotic connections to the dural sinus system, allowing for the direct modulation of brain temperatures. The generality of the vascular patterns discovered in iguanas were assessed by firsthand comparison with other squamates taxa (e.g., via dissection and osteological study) as well as the literature. Similar to extant archosaurs, iguanas and other squamates have highly vascularized sites of thermal exchange that likely support physiological thermoregulation that “fine tunes” temperatures attained through behavioral thermoregulation. PMID:26466378

Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

PubMed

Porter, William Ruger; Witmer, Lawrence M

2015-01-01

Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature, as well as pathways that would bypass neurosensory tissues. The orbital region houses a large venous sinus that receives cooled blood from the nasal region. Blood vessels from the nasal region and orbital sinus show anastomotic connections to the dural sinus system, allowing for the direct modulation of brain temperatures. The generality of the vascular patterns discovered in iguanas were assessed by firsthand comparison with other squamates taxa (e.g., via dissection and osteological study) as well as the literature. Similar to extant archosaurs, iguanas and other squamates have highly vascularized sites of thermal exchange that likely support physiological thermoregulation that "fine tunes" temperatures attained through behavioral thermoregulation.

Acute effect of L-arginine on hemodynamics and vascular capacitance in the canine pacing model of heart failure.

PubMed

Ogilvie, R I; Zborowska-Sluis, D

1995-09-01

The effect of L-arginine, 250 mg/kg over 10 min, on hemodynamics and venous function was studied in nine splenectomized dogs under light pentobarbital anesthesia before and after 17 +/- 1 days of rapid right ventricular pacing (RRVP) at 250 beats/min. Chronic RRVP induced mild congestive heart failure with increased mean circulatory filling (Pmcf), right atrial (Pra) and pulmonary capillary wedge pressures (Ppcw), and reduced cardiac output (CO). During the development of heart failure, total vascular compliance assessed from Pmcf-blood volume relationships during circulatory arrest was unchanged, but total vascular capacitance was markedly reduced, with an increase in stressed and reduction in unstressed blood volumes. At baseline but not after RRVP, L-arginine increased CO and reduced pulmonary vascular resistance. There were no significant changes in Pra, Ppcw, or total peripheral resistance. L-Arginine failed to alter total vascular compliance and capacitance or central blood volume in the baseline or failure state. These results do not support the hypothesis that increased Pmcf and reduced total vascular capacitance in the early stages of pacing-induced heart failure are caused by reduced substrate availability for or an endogenous competitive antagonist of NO synthase in venous endothelial cells.

Magnetic resonance imaging-derived arterial peak flow in peripheral arterial disease: towards a standardized measurement.

PubMed

Versluis, B; Nelemans, P J; Wildberger, J E; Schurink, G-W; Leiner, T; Backes, W H

2014-08-01

To determine the best location to measure the arterial peak flow (APF) in patients with peripheral arterial disease in order to facilitate clinical standardization. Two hundred and fifty-nine patients with varying degrees of peripheral artery disease (PAD) and 48 patients without PAD were included. All patients underwent magnetic resonance phase-contrast imaging of the common femoral artery (CFA), superficial femoral artery (SFA), and popliteal artery (PA). APF values of patients with PAD were compared with patients with no PAD. The discriminative ability to identify PAD was evaluated by means of receiver-operator characteristic curves and the corresponding areas under the curve (AUC). Mean APF values in patients with PAD were reduced by 42%, 55% and 59% compared with non-PAD patients for the CFA, SFA, and PA, respectively (p < .01). The AUC's were 0.84, 0.92, and 0.93 for the CFA, SFA, and PA, respectively. The APF measured at the level of the PA shows the largest differences between patients with PAD and patients with no PAD and the best discriminative ability compared with the APF acquired in the CFA or SFA. The PA seems to be the most suitable level for standardized flow measurements in patients with PAD in order to obtain relevant functional information about the vascular status. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Technology evaluation: VEGF165 gene therapy, Valentis Inc.

PubMed

Morse, M A

2001-02-01

Valentis Inc, formerly GeneMedicine, is developing a vascular endothelial growth factor (VEGF165) non-viral gene therapy using its proprietary PINC polymer for plasmid condensation. Two physician-initiated phase II angioplasty trials are ongoing, one for treating peripheral vascular disease and one for treating coronary artery disease [281714], [347153]. In February 2000, the trials were expected to be completed in the fourth quarter of 2000 [356225]; however, in October 2000, it was reported that the trial for peripheral vascular disease would be completed in the first quarter of 2001 [385232]. In March 2000, Valentis initiated a trial incorporating Valentis's DOTMA-based cationic lipid gene delivery system and the VEGF165 gene with Eurogene's local collar-reservoir delivery device. The trial is designed to demonstrate that the VEGF165 gene, delivered locally to the outside surface of a blood vessel, will transfect and express in the smooth muscle cells of the vessel wall [360683]. In March 1999, Valentis was awarded with a Phase II SBIR grant of $686,260. The aim of grant was to advance the development of non-viral gene therapies for ischemia. Specifically, Valentis intended to select an optimal promoter to be used with the VEGF expression plasmid. Valentis also intended to evaluate the gene therapy system in a rabbit ischemia model and complete the necessary preclinical studies for submission of an IND [318137].

Effect of upright tilt on ventricular/vascular coupling in chronically instrumented primates

NASA Technical Reports Server (NTRS)

Tran, C. C.; Latham, R. D.; Self, D. A.; Fanton, J. W.; White, C. D.; Owens, R. W.

1993-01-01

Studies of the hydraulic loading conditions on the heart in humans, especially pulsatile load, have primarily been limited to the supine state. Therefore, we have chosen a nonhuman primate model, the baboon, to assess left ventricular/vascular coupling in both supine and upright positions. Primate subjects were studied by catheterization under sedation and then after surgical implantation of transducers. This allowed the evaluation of postural stress in the chronically instrumented conscious baboon and then after light dissociative doses of ketamine. Basic hemodynamic variables were evaluated for baboons in supine and upright positions. Fourier analysis was applied to aortic pressure and flow to obtain input and characteristic impedance and the ratio of pulsatile (Wp) to total (Wt) left ventricular power (Wp/Wt). The aortic reflected, or backward, pressure was also calculated. Peripheral resistance increased (P = 0.01) and reflected pressure decreased (17.74 +/- 1.50 vs. 15.21 +/- 2 mmHg; P < 0.01) in upright subjects. Characteristic impedance and Wp/Wt were unchanged. Postoperatively, peripheral resistance increased (2,651 +/- 311 vs. 3,667 +/- 276; P < 0.05) and mean power and Wt decreased (P < 0.01) without changes in reflected pressure. All variables were unchanged after light dissociative doses of ketamine. Thus there is no significant change in efficiency of left ventricular/vascular coupling formulated in terms of Wp/Wt or input impedance with postural stress.

Twenty-four hour blood flow in the forefoot after reconstructive vascular surgery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jelnes, R.

Local blood flow in the forefoot (SBF) was measured continuously during 24 hours by 133xenon clearance technique in 10 patients prior to and at least 1 year after successful reconstructive vascular surgery for severe arterial insufficiency (mean: 18 months, range: 12-36). A group of 10 patients with normal peripheral circulation served as a control group. In spite of a considerable increase of the ankle/arm systolic blood pressure index--preoperative: 0.30 +/- 0.12, postoperative: 0.78 +/- 0.28 (mean +/- 1 SD)--the SBF decreased by 50% (p less than 0.001) following reconstructive vascular surgery during day activities. During sleep, however, SBF increased bymore » 80% (p less than 0.001). The relative changes in SBF from day to night at the postoperative examination did not differ from that of the control group, i.e., the normal 24-hour blood flow pattern had been obtained. These changes in SBF are explained by the reappearance of peripheral vasoregulatory mechanisms. Postreconstructive hyperemia was evaluated by the same technique. The changes in SBF following surgery in the positions supine, awake and supine, asleep were found to be insignificant (0.80 less than p less than 0.90). It is concluded that the long-term postreconstructive hyperemia merely is a reflection of the normal 24-hour blood flow pattern.« less

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.

Vascular and non-vascular plant community response to silvicultural practices and resultant microtopography creation in a forested wetland

Treesearch

Heidi M. Anderson; Margeret R. Gale; Martin F. Jurgensen; Carl C. Trettin

2007-01-01

Forested wetlands are important ecosystems valued for their indigenous plant communities, spatial heterogeneity, wildlife habitat, water quality, and timber resources. When harvested for timber, plant composition in these wetlands may change due to alteration in microsite habitats. Harvest severity also may affect plant composition. In this study, a mineral conifer...

Vascular complications following intra-aortic balloon pump implantation: an updated review

PubMed Central

de Jong, Monique M; Lorusso, Roberto; Al Awami, Fatima; Matteuci, Francesco; Parise, Orlando; Lozekoot, Pieter; Bonacchi, Massimo; Maessen, Jos G; Johnson, Daniel M; Gelsomino, Sandro

2017-01-01

Background: The use of the intra-aortic balloon pump (IABP) as a support device remains controversial due to the fact that a number of studies have shown no benefit in end mortality whilst using this device. One of the reasons for this could be the increase in vascular complications when using the pump. Therefore, the aim of the present review was to assess the current literature available with regards to IABP vascular complications during the clinical situation. Methods: A literature search was performed, searching for IABP complications in adult human studies between 1990 and 2016. Results: A total of 20 reports were identified as fitting the criteria of this study. The majority of vascular complications were limb ischemia, bleeding or mesenteric ischemia. The overall incidence of vascular complications ranged from 0.94% to 31.1%. Diabetes, peripheral vascular disease and hypertension, as well as smoking were all identified as risk factors for complications following IABP. Furthermore, studies supported the use of sheathless balloon insertion to reduce the risk of complications. Conclusion: Major vascular complications, including limb and mesenteric ischemia as well as bleeding and hemorrhage, have been associated with IABP. However, the incidence of these complications was generally low. Further studies are still required to truly understand the risk/benefit associated with the use of IABP. PMID:28816093

Mechanistic insights into the vascular effects of blueberries: Evidence from recent studies.

PubMed

Cutler, Brett Ronald; Petersen, Chrissa; Anandh Babu, Pon Velayutham

2017-06-01

Cardiovascular disease is the leading cause of death in the United States. Dietary habits influence a variety of cardiovascular complications such as peripheral artery disease, heart failure, and kidney disease. We along with others have previously reported the cardiovascular beneficial effects of dietary flavonoids. Anthocyanins, one class of flavonoids widely available in berries, have recently drawn wide scientific attention because of their diverse health benefits. Epidemiological, clinical, and animal studies indicate that blueberry anthocyanins exert protection against cardiovascular complications by acting on multiple targets in the vascular system. These include activating endothelial nitric oxide synthase signaling, reducing oxidative stress, improving inflammatory pathways, and ameliorating dyslipidemia. Anthocyanins are extensively metabolized in humans suggesting that their vascular benefits are likely mediated by their circulating metabolites. However, the bioactivities of blueberry metabolites are unknown. Evaluating the bioactivities of metabolites, analyzing their structure-activity relationship, and well-designed human trials are needed to understand the potential vascular effects of blueberries and their metabolites. Understanding the vascular effects will provide a solid scientific foundation to recommend blueberries to improve vascular health. This review highlights the recent developments in the understanding of the vascular effects of blueberries with special emphasis on the molecular mechanisms involved. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Interactive effects between plant functional types and soil factors on tundra species diversity and community composition.

PubMed

Iturrate-Garcia, Maitane; O'Brien, Michael J; Khitun, Olga; Abiven, Samuel; Niklaus, Pascal A; Schaepman-Strub, Gabriela

2016-11-01

Plant communities are coupled with abiotic factors, as species diversity and community composition both respond to and influence climate and soil characteristics. Interactions between vegetation and abiotic factors depend on plant functional types (PFT) as different growth forms will have differential responses to and effects on site characteristics. However, despite the importance of different PFT for community assembly and ecosystem functioning, research has mainly focused on vascular plants. Here, we established a set of observational plots in two contrasting habitats in northeastern Siberia in order to assess the relationship between species diversity and community composition with soil variables, as well as the relationship between vegetation cover and species diversity for two PFT (nonvascular and vascular). We found that nonvascular species diversity decreased with soil acidity and moisture and, to a lesser extent, with soil temperature and active layer thickness. In contrast, no such correlation was found for vascular species diversity. Differences in community composition were found mainly along soil acidity and moisture gradients. However, the proportion of variation in composition explained by the measured soil variables was much lower for nonvascular than for vascular species when considering the PFT separately. We also found different relationships between vegetation cover and species diversity according the PFT and habitat. In support of niche differentiation theory, species diversity and community composition were related to edaphic factors. The distinct relationships found for nonvascular and vascular species suggest the importance of considering multiple PFT when assessing species diversity and composition and their interaction with edaphic factors. Synthesis : Identifying vegetation responses to edaphic factors is a first step toward a better understanding of vegetation-soil feedbacks under climate change. Our results suggest that incorporating differential responses of PFT is important for predicting vegetation shifts, primary productivity, and in turn, ecosystem functioning in a changing climate.

Correlation Between Arterial FDG Uptake and Biomarkers in Peripheral Artery Disease

PubMed Central

Myers, Kelly S.; Rudd, James H. F.; Hailman, Eric P.; Bolognese, James A.; Burke, Joanne; Pinto, Cathy Anne; Klimas, Michael; Hargreaves, Richard; Dansky, Hayes M.; Fayad, Zahi A.

2014-01-01

OBJECTIVES A prospective, multicenter 18fluorine-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) imaging study was performed to estimate the correlations among arterial FDG uptake and atherosclerotic plaque biomarkers in patients with peripheral artery disease. BACKGROUND Inflammation within atherosclerotic plaques is associated with instability of the plaque and future cardiovascular events. Previous studies have shown that 18F-FDG-PET/CT is able to quantify inflammation within carotid artery atherosclerotic plaques, but no studies to date have investigated this correlation in peripheral arteries with immunohistochemical confirmation. METHODS Thirty patients across 5 study sites underwent 18F-FDG-PET/CT imaging before Silver-Hawk atherectomy (FoxHollow Technologies, Redwood City, California) for symptomatic common or superficial femoral arterial disease. Vascular FDG uptake (expressed as target-to-background ratio) was measured in the carotid arteries and aorta and femoral arteries, including the region of atherectomy. Immunohistochemistry was performed on the excised atherosclerotic plaque extracts, and cluster of differentiation 68 (CD68) level as a measure of macrophage content was determined. Correlations between target-to-background ratio of excised lesions, as well as entire arterial regions, and CD68 levels were determined. Imaging was performed during the 2 weeks before surgery in all cases. RESULTS Twenty-one patients had adequate-quality 18F-FDG-PET/CT peripheral artery images, and 34 plaque specimens were obtained. No significant correlation between lesion target-to-background ratio and CD68 level was observed. CONCLUSIONS There were no significant correlations between CD68 level (as a measure of macrophage content) and FDG uptake in the peripheral arteries in this multicenter study. Differences in lesion extraction technique, lesion size, the degree of inflammation, and imaging coregistration techniques may have been responsible for the failure to observe the strong correlations with vascular FDG uptake observed in previous studies of the carotid artery and in several animal models of atherosclerosis. PMID:22239891

A national survey of evolving management patterns for vascular injury.

PubMed

Burkhardt, Gabriel E; Rasmussen, Todd E; Propper, Brandon W; Lopez, Peter L; Gifford, Shaun M; Clouse, W Darrin

2009-01-01

The modern era has witnessed an increase in endovascular techniques used by physicians to treat vascular injury and age-related disease. As a consequence, the number of open vascular operations available for general surgical education has decreased dramatically. This changing paradigm threatens competence in vascular injury management achieved during surgical residency. The objective of this study is to sample perceptions on vascular injury treatment in the United States to highlight the need for planning for this important tenet of surgical education. An electronic survey was extended to board-certified surgeons through 3 professional societies, the Peripheral Vascular Surgery Society (PVSS), the Eastern Association for the Surgery of Trauma (EAST), and the American College of Surgeons (ACS). A total of 520 respondents were self-categorized as trauma (59%; n = 307), vascular (17%; n = 90), or general (19%; n = 99) surgeons. Respondents reported that general surgeons currently manage less than 10% of vascular injuries at their respective institutions. A 2.5-fold increase in endovascular treatment of vascular injury during the past decade was reported with interventional radiologists now involved in the management of up to 25% of injuries. Few general or trauma surgeons surveyed possessed a catheter-based skill set, although 38% of trauma surgeons expressed great interest in endovascular training. Additionally, a cadre of vascular surgeons (67%) affirmed a commitment to teaching vascular injury management. The results of this study confirm a diminished role for non-fellowship-trained surgeons in managing vascular injury. Despite an increased acceptance of endovascular techniques to manage trauma, general and trauma surgeons do not possess the skill set. Collaboration between surgical communities will be especially important to maintain high standards in vascular injury management.

A PEGylated platelet free plasma hydrogel based composite scaffold enables stable vascularization and targeted cell delivery for volumetric muscle loss.

PubMed

Aurora, Amit; Wrice, Nicole; Walters, Thomas J; Christy, Robert J; Natesan, Shanmugasundaram

2018-01-01

Extracellular matrix (ECM) scaffolds are being used for the clinical repair of soft tissue injuries. Although improved functional outcomes have been reported, ECM scaffolds show limited tissue specific remodeling response with concomitant deposition of fibrotic tissue. One plausible explanation is the regression of blood vessels which may be limiting the diffusion of oxygen and nutrients across the scaffold. Herein we develop a composite scaffold as a vasculo-inductive platform by integrating PEGylated platelet free plasma (PFP) hydrogel with a muscle derived ECM scaffold (m-ECM). In vitro, adipose derived stem cells (ASCs) seeded onto the composite scaffold differentiated into two distinct morphologies, a tubular network in the hydrogel, and elongated structures along the m-ECM scaffold. The composite scaffold showed a high expression of ITGA5, ITGB1, and FN and a synergistic up-regulation of ang1 and tie-2 transcripts. The in vitro ability of the composite scaffold to provide extracellular milieu for cell adhesion and molecular cues to support vessel formation was investigated in a rodent volumetric muscle loss (VML) model. The composite scaffold delivered with ASCs supported robust and stable vascularization. Additionally, the composite scaffold supported increased localization of ASCs in the defect demonstrating its ability for localized cell delivery. Interestingly, ASCs were observed homing in the injured muscle and around the perivascular space possibly to stabilize the host vasculature. In conclusion, the composite scaffold delivered with ASCs presents a promising approach for scaffold vascularization. The versatile nature of the composite scaffold also makes it easily adaptable for the repair of soft tissue injuries. Decellularized extracellular matrix (ECM) scaffolds when used for soft tissue repair is often accompanied by deposition of fibrotic tissue possibly due to limited scaffold vascularization, which limits the diffusion of oxygen and nutrients across the scaffold. Although a variety of scaffold vascularization strategies has been investigated, their limitations preclude rapid clinical translation. In this study we have developed a composite scaffold by integrating bi-functional polyethylene glycol modified platelet free plasma (PEGylated PFP) with adipose derived stem cells (ASCs) along with a muscle derived ECM scaffold (m-ECM). The composite scaffold provides a vasculo-inductive and an effective cell delivery platform for volumetric muscle loss. Copyright © 2017 Acta Materialia Inc. All rights reserved.

Altered Blood Flow Response to Small Muscle Mass Exercise in Cancer Survivors Treated With Adjuvant Therapy.

PubMed

Didier, Kaylin D; Ederer, Austin K; Reiter, Landon K; Brown, Michael; Hardy, Rachel; Caldwell, Jacob; Black, Christopher; Bemben, Michael G; Ade, Carl J

2017-02-07

Adjuvant cancer treatments have been shown to decrease cardiac function. In addition to changes in cardiovascular risk, there are several additional functional consequences including decreases in exercise capacity and increased incidence of cancer-related fatigue. However, the effects of adjuvant cancer treatment on peripheral vascular function during exercise in cancer survivors have not been well documented. We investigated the vascular responses to exercise in cancer survivors previously treated with adjuvant cancer therapies. Peripheral vascular responses were investigated in 11 cancer survivors previously treated with adjuvant cancer therapies (age 58±6 years, 34±30 months from diagnosis) and 9 healthy controls group matched for age, sex, and maximal voluntary contraction. A dynamic handgrip exercise test at 20% maximal voluntary contraction was performed with simultaneous measurements of forearm blood flow and mean arterial pressure. Forearm vascular conductance was calculated from forearm blood flow and mean arterial pressure. Left ventricular ejection time index (LVETi) was derived from the arterial pressure wave form. Forearm blood flow was attenuated in cancer therapies compared to control at 20% maximal voluntary contraction (189.8±53.8 vs 247.9±80.3 mL·min -1 , respectively). Forearm vascular conductance was not different between groups at rest or during exercise. Mean arterial pressure response to exercise was attenuated in cancer therapies compared to controls (107.8±10.8 vs 119.2±16.2 mm Hg). LEVTi was lower in cancer therapies compared to controls. These data suggest an attenuated exercise blood flow response in cancer survivors ≈34 months following adjuvant cancer therapy that may be attributed to an attenuated increase in mean arterial pressure. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Surgical and Antimicrobial Treatment of Prosthetic Vascular Graft Infections at Different Surgical Sites: A Retrospective Study of Treatment Outcomes

PubMed Central

Elzi, Luigia; Gurke, Lorenz; Battegay, Manuel; Widmer, Andreas F.; Weisser, Maja

2014-01-01

Objective Little is known about optimal management of prosthetic vascular graft infections, which are a rare but serious complication associated with graft implants. The goal of this study was to compare and characterize these infections with respect to the location of the graft and to identify factors associated with outcome. Methods This was a retrospective study over more than a decade at a tertiary care university hospital that has an established multidisciplinary approach to treating graft infections. Cases of possible prosthetic vascular graft infection were identified from the hospital's infectious diseases database and evaluated against strict diagnostic criteria. Patients were divided into groups according to the locations of their grafts: thoracic-aortic, abdominal-aortic, or peripheral-arterial. Statistical analyses included evaluation of patient and infection characteristics, time to treatment failure, and factors associated specifically with cure rates in aortic graft infections. The primary endpoint was cure at one year after diagnosis of the infection. Results Characterization of graft infections according to the graft location did show that these infections differ in terms of their characteristics and that the prognosis for treatment seems to be influenced by the location of the infection. Cure rate and all-cause mortality at one year were 87.5% and 12.5% in 24 patients with thoracic-aortic graft infections, 37.0% and 55.6% in 27 patients with abdominal-aortic graft infections, and 70.0% and 30.0% in 10 patients with peripheral-arterial graft infections. In uni- and multivariate analysis, the type of surgical intervention used in managing infections (graft retention versus graft replacement) did not affect primary outcome, whereas a rifampicin-based antimicrobial regimen was associated with a higher cure rate. Conclusions We recommend that future prospective studies differentiate prosthetic vascular graft infections according to the location of the grafts and that rifampicin-based antimicrobial regimens be evaluated in clinical trials involving vascular graft infections caused by staphylococci. PMID:25393400

Substantial adverse association of visual and vascular comorbidities on visual disability in multiple sclerosis.

PubMed

Marrie, Ruth Ann; Cutter, Gary; Tyry, Tuula

2011-12-01

Visual comorbidities are common in multiple sclerosis (MS) but the impact of visual comorbidities on visual disability is unknown. We assessed the impact of visual and vascular comorbidities on severity of visual disability in MS. In 2006, we queried participants of the North American Research Committee on Multiple Sclerosis (NARCOMS) about cataracts, glaucoma, uveitis, hypertension, hypercholesterolemia, heart disease, diabetes and peripheral vascular disease. We assessed visual disability using the Vision subscale of Performance Scales. Using Cox regression, we investigated whether visual or vascular comorbidities affected the time between MS symptom onset and the development of mild, moderate and severe visual disability. Of 8983 respondents, 1415 (15.9%) reported a visual comorbidity while 4745 (52.8%) reported a vascular comorbidity. The median (interquartile range) visual score was 1 (0-2). In a multivariable Cox model the risk of mild visual disability was higher among participants with vascular (hazard ratio [HR] 1.45; 95% confidence interval [CI]: 1.39-1.51) and visual comorbidities (HR 1.47; 95% CI: 1.37-1.59). Vascular and visual comorbidities were similarly associated with increased risks of moderate and severe visual disability. Visual and vascular comorbidities are associated with progression of visual disability in MS. Clinicians hearing reports of worsening visual symptoms in MS patients should consider visual comorbidities as contributing factors. Further study of these issues using objective, systematic neuro-ophthalmologic evaluations is warranted.

'Multi-associations': predisposed to misinterpretation of peripheral tissue oxygenation and circulation in neonates.

PubMed

Pichler, Gerhard; Pocivalnik, Mirjam; Riedl, Regina; Pichler-Stachl, Elisabeth; Morris, Nicholas; Zotter, Heinz; Müller, Wilhelm; Urlesberger, Berndt

2011-08-01

Interpretation of peripheral circulation in ill neonates is crucial but difficult. The aim was to analyse parameters potentially influencing peripheral oxygenation and circulation. In a prospective observational cohort study in 116 cardio-circulatory stable neonates, peripheral muscle near-infrared spectroscopy (NIRS) with venous occlusion was performed. Tissue oxygenation index (TOI), mixed venous oxygenation (SvO(2)), fractional oxygen extraction (FOE), fractional tissue oxygen extraction (FTOE), haemoglobin flow (Hbflow), oxygen delivery (DO(2)), oxygen consumption (VO(2)), and vascular resistance (VR) were assessed. Correlation coefficients between NIRS parameters and demographic parameters (gestational age, birth weight, age, actual weight, diameter of calf, subcutaneous adipose tissue), monitoring parameters (heart rate, arterial oxygen saturation (SaO(2)), mean blood pressure (MAP), core/peripheral temperature, central/peripheral capillary refill time) and laboratory parameters (haemoglobin concentration (Hb-blood), pCO(2)) were calculated. All demographic parameters except for Hbflow and DO(2) correlated with NIRS parameters. Heart rate correlated with TOI, SvO(2), VO(2) and VR. SaO(2) correlated with FOE/FTOE. MAP correlated with Hbflow, DO(2), VO(2) and VR. Core temperature correlated with FTOE. Peripheral temperature correlated with all NIRS parameters except VO(2). Hb-blood correlated with FOE and VR. pCO(2) levels correlated with TOI and SvO(2). The presence of multiple interdependent factors associated with peripheral oxygenation and circulation highlights the difficulty in interpreting NIRS data. Nevertheless, these findings have to be taken into account when analysing peripheral oxygenation and circulation data.

The Retrograde Transvenous Push-Through Method: A Novel Treatment of Peripheral Arteriovenous Malformations with Dominant Venous Outflow

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wohlgemuth, Walter A., E-mail: walter.wohlgemuth@ukr.de; Müller-Wille, René, E-mail: Rene.Mueller-Wille@ukr.de; Teusch, Veronika I., E-mail: Veronika.Teusch@gmx.de

2015-06-15

PurposeTo evaluate the efficacy and safety of a novel retrograde transvenous embolization technique of peripheral arteriovenous malformations (AVMs) using Onyx.Materials and MethodsWe conducted a retrospective analysis of all patients who underwent transvenous retrograde Onyx embolization of peripheral AVMs with dominant venous outflow over a 29-month period. The embolization is aimed at retrograde filling of the nidus after building a solid plug in the dominant venous outflow (push-through). Classification, clinical signs, technical aspects, clinical and technical success rates, and complications were recorded. Short-term outcome was assessed.Results11 Symptomatic patients (8 female; mean age 31.4 years) were treated at our Vascular Anomalies Center withmore » this method between January 2012 and May 2014. The AVMs were located on the upper extremity (n = 3), pelvis (n = 2), buttock (n = 2), and lower extremity (n = 4). Retrograde embolization was successfully carried out after preparatory transarterial-flow reduction in eight cases (73 %) and venous-flow reduction with Amplatzer Vascular Plugs in four cases (36 %). Complete devascularization (n = 10; 91 %) or 95 % devascularization (n = 1; 9 %) led to complete resolution (n = 8; 73 %) or improvement of clinical symptoms (n = 3; 27 %). One minor complication occurred (pain and swelling). During a mean follow-up time of 8 months, one clinically asymptomatic recurrence of AVM was detected.ConclusionInitial results suggest that retrograde transvenous Onyx embolization of peripheral AVMs with dominant venous outflow is a safe and effective novel technique with a low complication rate.« less

Peripheral Endothelial Function After Arterial Switch Operation for D-looped Transposition of the Great Arteries.

PubMed

Sun, Heather Y; Stauffer, Katie Jo; Nourse, Susan E; Vu, Chau; Selamet Tierney, Elif Seda

2017-06-01

Coronary artery re-implantation during arterial switch operation in patients with D-looped transposition of the great arteries (D-TGA) can alter coronary arterial flow and increase shear stress, leading to local endothelial dysfunction, although prior studies have conflicting results. Endothelial pulse amplitude testing can predict coronary endothelial dysfunction by peripheral arterial testing. This study tested if, compared to healthy controls, patients with D-TGA after arterial switch operation had peripheral endothelial dysfunction. Patient inclusion criteria were (1) D-TGA after neonatal arterial switch operation; (2) age 9-29 years; (3) absence of known cardiovascular risk factors such as hypertension, diabetes, hypercholesterolemia, vascular disease, recurrent vasovagal syncope, and coronary artery disease; and (4) ability to comply with overnight fasting. Exclusion criteria included (1) body mass index ≥85th percentile, (2) use of medications affecting vascular tone, or (3) acute illness. We assessed endothelial function by endothelial pulse amplitude testing and compared the results to our previously published data in healthy controls (n = 57). We tested 20 D-TGA patients (16.4 ± 4.8 years old) who have undergone arterial switch operation at a median age of 5 days (0-61 days). Endothelial pulse amplitude testing indices were similar between patients with D-TGA and controls (1.78 ± 0.61 vs. 1.73 ± 0.54, p = 0.73).In our study population of children and young adults, there was no evidence of peripheral endothelial dysfunction in patients with D-TGA who have undergone arterial switch operation. Our results support the theory that coronary arterial wall thickening and abnormal vasodilation reported in these patients is a localized phenomenon and not reflective of overall atherosclerotic burden.

Catastrophic secondary antiphospholipid syndrome with peripheral nervous system involvement: a case report.

PubMed

Erten, Nilgun; Saka, Bulent; Karan, M Akif; Parman, Yesim; Umman, Berrin; Tascioglu, Cemil

2004-04-01

A 34-year-old woman was admitted to our emergency room with a high fever, abdominal pain, dyspnea and confusion. High fever and abdominal pain had first occured after a cystocele operation 5 months earlier. Later, congestive heart failure with mural thrombus formation, peripheral polyneuropathy and ischemic cerebrovascular accident were identified in clinical follow-ups, and multiple arterial and venous thromboses were seen on cranial and abdominal magnetic resonance imaging angiography. The patient's symptoms improved with anticoagulant treatment. Antiphospholipid syndrome with elevated serum anticardiolipin IgG levels was diagnosed, and ischemic peripheral polyneuropathy with axonal degeneration was determined by sural nerve biopsy. In antiphospholipid syndrome, elevated anticardiolipin antibodies appear to be the most common acquired blood protein defect causing thrombosis. Disseminated vascular thrombosis in catastrophic antiphospholipid syndrome can result in multiorgan failure with increased morbidity and mortality. It rarely occurs secondary to various infections as in the case of our patient, who suffered postoperative intraabdominal infection. It is important to note that peripheral nervous system involvement is rare in antiphospholipid syndrome.

Association of peripheral neuropathy with circulating advanced glycation end products, soluble receptor for advanced glycation end products and other risk factors in patients with type 2 diabetes.

PubMed

Aubert, C E; Michel, P-L; Gillery, P; Jaisson, S; Fonfrede, M; Morel, F; Hartemann, A; Bourron, O

2014-11-01

The pathogenesis of diabetic peripheral neuropathy remains uncertain and nonenzymatic glycoxidation is one of the contributing mechanisms. The aim of this study was to assess the respective relationship of diabetic peripheral neuropathy with glycoxidation, compared with other identified risk factors, in patients with type 2 diabetes. We included 198 patients with type 2 diabetes and high risk for vascular complications. Circulating concentrations of three advanced glycation end products (carboxymethyllysine, methyl-glyoxal-hydroimidazolone-1, pentosidine) and of their soluble receptor (sRAGE) were measured. Peripheral neuropathy was assessed by the neuropathy disability score and by the monofilament test and defined as either an abnormal monofilament test and/or a neuropathy disability score ≥6. Multivariate regression analyses were performed adjusting for potential confounding factors for neuropathy: age, gender, diabetes duration, current smoking, systolic blood pressure, waist circumference, height, peripheral arterial occlusive disease, glycated haemoglobin, estimated glomerular filtration rate and lipid profile. Prevalence of peripheral neuropathy was 20.7%. sRAGE and carboxymethyllysine were independently and positively associated with the presence of peripheral neuropathy. No significant association was found between peripheral neuropathy and methyl-glyoxal-hydroimidazolone-1 or pentosidine. Waist circumference, height and peripheral arterial occlusive disease were independently associated with peripheral neuropathy. Carboxymethyllysine and sRAGE were independently associated with peripheral neuropathy in patients with type 2 diabetes. Although the conclusions are limited by the absence of a healthy control population, this study confirms the relationship between advanced glycoxidation and diabetic peripheral neuropathy, independently of other risk factors. Copyright © 2014 John Wiley & Sons, Ltd.

Presence of intracranial artery calcification is associated with mortality and vascular events in patients with ischemic stroke after hospital discharge: a cohort study.

PubMed

Bugnicourt, Jean-Marc; Leclercq, Claire; Chillon, Jean-Marc; Diouf, Momar; Deramond, Hervé; Canaple, Sandrine; Lamy, Chantal; Massy, Ziad A; Godefroy, Olivier

2011-12-01

Although intracranial artery calcification (IAC) has been reported to be a risk factor for ischemic stroke, the prognostic implications of IAC in stroke outcome are unknown. The purpose of this study was to determine the association between IAC and risk of vascular events and death in patients with stroke after hospital discharge. All patients with ischemic stroke over a 1-year period were included (n=302). IAC, assessed by multidetector CT, was defined as hyperdense foci (peak density>130 Hounsfield units) and assessed in the 7 major cerebral arteries. The IAC scores ranged from 0 (no calcification) to 7. Follow-up information on major clinical events (including fatal or nonfatal ischemic stroke, cardiac and peripheral artery events, and all-cause death) was obtained by means of a structured phone interview. IAC was present in 260 patients (83%). With a mean follow-up of 773±223 days, 88 major clinical events occurred in 67 patients (22%): 45 new ischemic vascular events (ischemic stroke: n=22; cardiac event: n=15; peripheral artery event: n=8) and 43 deaths from any cause. Patients with the highest IAC scores had significantly higher rates of death and vascular events than those with the lowest IAC scores (log rank test, P=0.029). In the Cox proportional hazards regression model, the IAC score was significantly associated with major clinical events (hazard ratio, 1.34; 95% CI, 1.11-1.61; P=0.002). In patients with ischemic stroke, IAC detection may constitute a simple marker of a high risk of future major clinical events.

Glioblastoma: Vascular Habitats Detected at Preoperative Dynamic Susceptibility-weighted Contrast-enhanced Perfusion MR Imaging Predict Survival.

PubMed

Juan-Albarracín, Javier; Fuster-Garcia, Elies; Pérez-Girbés, Alexandre; Aparici-Robles, Fernando; Alberich-Bayarri, Ángel; Revert-Ventura, Antonio; Martí-Bonmatí, Luis; García-Gómez, Juan M

2018-06-01

Purpose To determine if preoperative vascular heterogeneity of glioblastoma is predictive of overall survival of patients undergoing standard-of-care treatment by using an unsupervised multiparametric perfusion-based habitat-discovery algorithm. Materials and Methods Preoperative magnetic resonance (MR) imaging including dynamic susceptibility-weighted contrast material-enhanced perfusion studies in 50 consecutive patients with glioblastoma were retrieved. Perfusion parameters of glioblastoma were analyzed and used to automatically draw four reproducible habitats that describe the tumor vascular heterogeneity: high-angiogenic and low-angiogenic regions of the enhancing tumor, potentially tumor-infiltrated peripheral edema, and vasogenic edema. Kaplan-Meier and Cox proportional hazard analyses were conducted to assess the prognostic potential of the hemodynamic tissue signature to predict patient survival. Results Cox regression analysis yielded a significant correlation between patients' survival and maximum relative cerebral blood volume (rCBV max ) and maximum relative cerebral blood flow (rCBF max ) in high-angiogenic and low-angiogenic habitats (P < .01, false discovery rate-corrected P < .05). Moreover, rCBF max in the potentially tumor-infiltrated peripheral edema habitat was also significantly correlated (P < .05, false discovery rate-corrected P < .05). Kaplan-Meier analysis demonstrated significant differences between the observed survival of populations divided according to the median of the rCBV max or rCBF max at the high-angiogenic and low-angiogenic habitats (log-rank test P < .05, false discovery rate-corrected P < .05), with an average survival increase of 230 days. Conclusion Preoperative perfusion heterogeneity contains relevant information about overall survival in patients who undergo standard-of-care treatment. The hemodynamic tissue signature method automatically describes this heterogeneity, providing a set of vascular habitats with high prognostic capabilities. © RSNA, 2018.

Bioresorbable Everolimus-Eluting Vascular Scaffold for Patients With Peripheral Artery Disease (ESPRIT I): 2-Year Clinical and Imaging Results.

PubMed

Lammer, Johannes; Bosiers, Marc; Deloose, Koen; Schmidt, Andrej; Zeller, Thomas; Wolf, Florian; Lansink, Wouter; Sauguet, Antoine; Vermassen, Frank; Lauwers, Geert; Scheinert, Dierk; Popma, Jeffrey J; McGreevy, Robert; Rapoza, Richard; Schwartz, Lewis B; Jaff, Michael R

2016-06-13

This is the first-in-human study of a drug-eluting bioresorbable vascular scaffold (BVS) for treatment of peripheral artery disease (PAD) involving the external iliac artery (EIA) and superficial femoral artery (SFA). Drug-eluting BVS has shown promise in coronary arteries. The ESPRIT BVS system is a device-drug combination consisting of an everolimus-eluting poly-l-lactide scaffold. Safety and performance were evaluated in 35 subjects with symptomatic claudication. Lesions were located in the SFA (88.6%) and EIA (11.4%). Mean lesion length was 35.7 ± 16.0 mm. The study device was successfully deployed in 100% of cases, without recoil. Procedure-related minor complications were observed in 3 patients (groin hematoma, dissection). Within 2 years there was 1 unrelated death, but no patients in this cohort had an amputation. At 1 and 2 years, the binary restenosis rates were 12.1% and 16.1%, respectively, and target lesion revascularization was performed in 3 of 34 patients (8.8%) and 4 of 32 patients (11.8%), respectively. The ankle brachial index 0.75 ± 0.14 improved from pre-procedure to 0.96 ± 0.16 at 2 years' follow-up. At 2 years, 71.0% of the patients were Rutherford-Becker 0, and 93.5% achieved a maximum walking distance of 1,500 feet. The safety of the ESPRIT BVS was demonstrated with no procedure or device-related deaths or amputations within 2 years. The low occurrence of revascularizations was consistent with duplex-ultrasonography showing sustained patency at 2-years. (A Clinical Evaluation of the Abbott Vascular ESPRIT BVS [Bioresorbable Vascular Scaffold] System [ESPRIT I]; NCT01468974). Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Lateral saphenous vein responses to serotonergic and a-adrenergic receptor agonists increase with time off endophyte-infected tall fescue

USDA-ARS?s Scientific Manuscript database

Previous research has indicated that serotonergic and a-adrenergic receptors in peripheral vasculature are affected by exposure of cattle grazing toxic endophyte-infected (E+) tall fescue (TF; Lolium arundinaceum). This study was conducted to investigate changes in vascular contractile response over...

Nutrition in the prevention of Coronary Heart Disease and the management of lipoprotein disorders

USDA-ARS?s Scientific Manuscript database

Cardiovascular disease (CVD) is comprised of coronary heart disease (CHD), stroke, and peripheral vascular disease (PVD). CVD is caused by progressive narrowing and blockage of arteries supplying the heart, brain, and other tissues and organs. CVD is the leading cause of death and disability in our ...

[The use of low-frequency magnetotherapy and EHF puncture in the combined treatment of arterial hypertension in vibration-induced disease].

PubMed

Drobyshev, V A; Filippova, G N; Loseva, M I; Shpagina, L A; Shelepova, N V; Zhelezniak, M S

2000-01-01

Combination of EHF therapy + magnetotherapy + drugs results in faster and persistent hypotensive and analgetic effect compared to standard drug therapy, potentiates action of vascular drugs on cerebral and peripheral circulation, reduces dose of hypotensive drugs in patients with arterial hypertension and vibration disease.

[Low-energy wideband electromagnetic radiation and manual therapy in the treatment of neurological manifestations of spinal osteochondrosis].

PubMed

Afoshin, S A; Gerasimenko, M Iu

2006-01-01

It is shown that the advanced technique of low-energy wideband electromagnetic radiation improves vascular tonicity and peripheral circulation while a modified technique of manual therapy facilitates movements in the affected part of the spine and reduces tonicity of the muscles involved in the pathological process.

Peripheral Applications of Drug-Coated Balloons: Past, Present and Future

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krokidis, Miltiadis, E-mail: mkrokidis@hotmail.com; Spiliopoulos, Stavros, E-mail: stavspiliop@upatras.gr; Katsanos, Konstantinos, E-mail: katsanos@med.upatras.gr

2013-04-15

Drug-coated balloon (DCB) technologies represent the latest and hottest development in the field of endovascular treatment of peripheral arterial disease. Initial experience with paclitaxel-coated balloon use in the femoral artery has demonstrated lower mid-term restenosis and superior mid-term clinical outcomes in terms of improved wound healing and reduced repeat angioplasty rates compared with standard balloon angioplasty. Many companies are presently developing and/or improving DCB catheters and therefore ongoing, technical improvements of the already existing platforms, new drugs, and innovative carriers are expected. The ongoing basic research studies and various multicenter randomized, controlled trials that are currently in progress will offermore » valuable scientific insights regarding the long-term effectiveness and other crucial issues, such as efficacy in various vascular beds, optimal balloon dosage, and post angioplasty antiplatelet therapy. Future applications of these devices also could include in-stent restenosis, anastomotic stenosis of surgical bypass, and benign stenoses of the central venous system. The authors envision that DCB angioplasty will evolve to a major paradigm shift in the endovascular treatment of occlusive vascular diseases.« less

Ulcer osteoma and periosteal reactions to chronic leg ulcers.

PubMed

Karasick, D; Schweitzer, M E; Deely, D M

1997-01-01

The purpose of this study was to describe the types of periosteal reaction seen in response to long-standing leg ulcers and to differentiate the types associated with osteomyelitis. Over a 10-year span, we retrospectively evaluated the radiographs of 20 patients with lower leg soft-tissue ulceration and adjacent periosteal bone reaction of the tibia or fibula. Two of us evaluated the location and appearance of periosteal reaction, and one of us evaluated the patients' medical records for evidence of peripheral vascular disease, systemic illnesses, and osteomyelitis. Twelve patients had organized periosteal reactions that resulted in the appearance of ulcer osteoma. None of these patients subsequently developed osteomyelitis. Eight patients had interrupted lamellar nodular periosteal reactions; six of the eight patients had superimposed osteomyelitis. Our study showed two types of periosteal response to chronic leg ulcers: a solid organized type that over time formed an ulcer osteoma and a lamellar nodular type that was often associated with osteomyelitis. Both types of ulcers were seen in patients with peripheral vascular disease, IV drug abuse, sickle cell disease, and neurologic impairment.

Endoscopic high-resolution auto fluorescence imaging and optical coherence tomography of airways in vivo (Conference Presentation)

NASA Astrophysics Data System (ADS)

Pahlevaninezhad, Hamid; Lee, Anthony; Hohert, Geoffrey; Schwartz, Carley; Shaipanich, Tawimas; Ritchie, Alexander J.; Zhang, Wei; MacAulay, Calum E.; Lam, Stephen; Lane, Pierre M.

2016-03-01

In this work, we present multimodal imaging of peripheral airways in vivo using an endoscopic imaging system capable of co-registered optical coherence tomography and autofluorescence imaging (OCT-AFI). This system employs a 0.9 mm diameter double-clad fiber optic-based catheter for endoscopic imaging of small peripheral airways. Optical coherence tomography (OCT) can visualize detailed airway morphology in the lung periphery and autofluorescence imaging (AFI) can visualize fluorescent tissue components such as collagen and elastin, improving the detection of airway lesions. Results from in vivo imaging of 40 patients indicate that OCT and AFI offer complementary information that may increase the ability to identify pulmonary nodules in the lung periphery and improve the safety of biopsy collection by identifying large blood vessels. AFI can rapidly visualize in vivo vascular networks using fast scanning parameters resulting in vascular-sensitive imaging with less breathing/cardiac motion artifacts compared to Doppler OCT imaging. By providing complementary information about structure and function of tissue, OCT-AFI may improve site selection during biopsy collection in the lung periphery.

Multidisciplinary approach to the diagnosis and management of patients with peripheral arterial disease

PubMed Central

Walker, Craig M; Bunch, Frank T; Cavros, Nick G; Dippel, Eric J

2015-01-01

Peripheral arterial disease (PAD) is frequently diagnosed after permanent damage has occurred, resulting in a high rate of morbidity, amputation, and loss of life. Early and ongoing diagnosis and treatment is required for this progressive disease. Lifestyle modifications can prevent or delay disease progression and improve symptoms. Limb-sparing endovascular interventions can restore circulation based on appropriate diagnostic testing to pinpoint vascular targets, and intervention must occur as early as possible to ensure optimal clinical outcomes. An algorithm for the diagnosis and management of PAD was developed to enable a collaborative approach between the family practice and primary care physician or internist and various specialists that may include a diabetologist, endocrinologist, smoking cessation expert, hypertension and lipid specialist, endovascular interventionalist, vascular surgeon, orthopedist, neurologist, nurse practitioner, podiatrist, wound healing expert, and/or others. A multidisciplinary team working together has the greatest chance of providing optimal care for the patient with PAD and ensuring ongoing surveillance of the patient’s overall health, ultimately resulting in better quality of life and increased longevity for patients with PAD. PMID:26203234

Novel Strategies to Improve Immunomodulatin and Non Invasive Clinical Monitoring in VCA

DTIC Science & Technology

2016-08-01

to patients with severe, unreconstructable vascularized composite tissue defects by safe VCA protocols with minimal side effects. Our specific aims...histology and ultrasound biomicroscopy (UBM). We are enrolling 5 subjects for VCA. ɛ months after VCA, once recipient and allograft are stable, we will...their treatment outcomes. Vascularized composite allotransplants provide a mean to functionally and cosmetically restore these tissues ; however, at

Influences of maternal nutritional status on vascular function in the offspring.

PubMed

Poston, Lucilla

2007-08-01

Fetal growth restriction leading to low birthweight is associated with increased risk of ischaemic heart disease and hypertension in later life. Increasingly, it is recognised that cardiovascular risk may also be initiated in early life when the fetus and neonate are exposed to maternal nutritional excess. This review summarises the studies in man and animals that have investigated the potential role of vascular disorders in the aetiology of atherosclerosis and hypertension arising from early life nutritional deprivation or excess. Malfunction of the arterial endothelial cell layer in the offspring has been frequently described in association with both maternal under and overnutritional states and may play a permissive role in the origin of these disorders. Also prevalent is evidence for increased stiffness of the large arteries which may contribute to systolic hypertension. Further investigation is required into the intriguing suggestion that early life nutritional imbalance may adversely influence vascular angiogenesis leading to rarefaction and increased peripheral vascular resistance.

Vascular surgery knowledge and exposure obtained during medical school and the potential impact on career decisions.

PubMed

Singh, Niten; Causey, Wayne; Brounts, Lionel; Clouse, W Darrin; Curry, Thomas; Andersen, Charles

2010-01-01

The pathway to primary certification in vascular surgery is evolving, requiring trainees to make earlier career decisions. The goal of this study was to evaluate exposure to and knowledge of vascular surgery obtained during medical school that could affect career decisions. A survey was conducted of recent medical school graduates entering military residency programs. Questions were designed to ascertain the medical school attended and degree obtained, exposure to and perception of vascular surgery, and basic vascular surgery knowledge. Of 316 individuals who were identified and sent surveys, 218 (69%) responded. There were 131 allopathic graduates (60%), 87 (40%) osteopathic graduates, and 53 (25%) were entering a surgical residency. Clinical clerkships (32%) were the primary reason for specialty selection, followed by lifestyle (29%). Most respondents (66%) did not have a vascular clinical clerkship. Regarding perception, 56% of respondents would consult interventional radiology for a peripheral arteriogram vs vascular surgery (39%). The mean score of the knowledge-based questions was 69%. Incoming postgraduate year (PGY) 1 surgical residents had a statistically higher mean score on the knowledge portion (P < .001). In addition, a positive correlation was noted with the number of weeks spent on a surgical (P < .03) and a vascular surgical (P < .001) rotation and the mean score. Subgroup analysis revealed a higher percentage of individuals with a vascular clerkship achieved a "high" score vs those without a vascular surgery clerkship (P < .001). Our cohort of medical school graduates had limited exposure to and knowledge of vascular surgery. Providing more clinical exposure in medical school appears necessary to ensure success of the modified pathways for primary certification in vascular surgery. Published by Mosby, Inc.

Insulin sensitizers prevent fine particulate matter-induced vascular insulin resistance and changes in endothelial progenitor cell homeostasis

PubMed Central

McCracken, James P.; Bhatnagar, Aruni; Conklin, Daniel J.

2016-01-01

Exposure to fine particular matter (PM2.5) increases the risk of developing cardiovascular disease and Type 2 diabetes. Because blood vessels are sensitive targets of air pollutant exposure, we examined the effects of concentrated ambient PM2.5 (CAP) on vascular insulin sensitivity and circulating levels of endothelial progenitor cells (EPCs), which reflect cardiovascular health. We found that CAP exposure for 9 days decreased insulin-stimulated Akt phosphorylation in the aorta of mice maintained on control diet. This change was accompanied by the induction of IL-1β and increases in the abundance of cleaved IL-18 and p10 subunit of Casp-1, consistent with the activation of the inflammasome pathway. CAP exposure also suppressed circulating levels of EPCs (Flk-1+/Sca-1+ cells), while enhancing the bone marrow abundance of these cells. Although similar changes in vascular insulin signaling and EPC levels were observed in mice fed high-fat diet, CAP exposure did not exacerbate diet-induced changes in vascular insulin resistance or EPC homeostasis. Treatment with an insulin sensitizer, metformin or rosiglitazone, prevented CAP-induced vascular insulin resistance and NF-κB and inflammasome activation and restored peripheral blood and bone marrow EPC levels. These findings suggest that PM2.5 exposure induces diet-independent vascular insulin resistance and inflammation and prevents EPC mobilization, and that this EPC mobilization defect could be mediated by vascular insulin resistance. Impaired vascular insulin sensitivity may be an important mechanism underlying PM2.5-induced vascular injury, and pharmacological sensitization to insulin action could potentially prevent deficits in vascular repair and mitigate vascular inflammation due to exposure to elevated levels of ambient air pollution. Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/particulate-matter-induced-vascular-insulin-resistance/. PMID:27016579

Skin temperature and core-peripheral temperature gradient as markers of hemodynamic status in critically ill patients: a review.

PubMed

Schey, Bernadette M; Williams, David Y; Bucknall, Tracey

2010-01-01

To examine the evidential basis underpinning the monitoring of skin temperature and core-peripheral temperature gradient as elements of hemodynamic assessment in critically ill and adult cardiac surgical patients. Twenty-six studies examining the efficacy of skin temperature or temperature gradient as markers of hemodynamic status were selected as part of an integrative review. Evidence pertaining to the efficacy of these parameters as markers of cardiac function is equivocal and has not been well appraised in the adult cardiac surgical population. Skin temperature and systemic vascular resistance are also affected by factors other than cardiac output. Skin temperature and core-peripheral temperature gradient should not be considered in isolation from other hemodynamic parameters when assessing cardiac status until they are validated by further large-scale prospective studies. 2010. Published by Mosby, Inc.

Microencapsulated VEGF gene-modified umbilical cord mesenchymal stromal cells promote the vascularization of tissue-engineered dermis: an experimental study.

PubMed

Han, Yanfu; Tao, Ran; Han, Yanqing; Sun, Tianjun; Chai, Jiake; Xu, Guang; Liu, Jing

2014-02-01

Tissue-engineered dermis (TED) is thought to be the best treatment for skin defect wounds; however, lack of vascular structures in these products can cause slow vascularization or even transplant failure. We assessed the therapeutic potential of microencapsulated human umbilical cord mesenchymal stromal cells (hUCMSCs) expressing vascular endothelial growth factor (VEGF) in vascularization of TED. hUCMSCs were isolated by means of enzymatic digestion and identified by means of testing biological characteristics. hUCMSCs were induced to differentiate into dermal fibroblasts in conditioned induction media. Collagen-chitosan laser drilling acellular dermal matrix (ADM) composite scaffold was prepared by means of the freeze dehydration and dehydrothermal cross-linking method. hUCMSC-derived fibroblasts were implanted on composite scaffolds to construct TED. TED with microencapsulated VEGF gene-modified hUCMSCs was then transplanted into skin defect wounds in pigs. The angiogenesis of TED at 1 week and status of wound healing at 3 weeks were observed. The collagen-chitosan laser ADM composite has a uniform microporous structure. This composite has been used to grow hUCMSC-derived fibroblasts in vitro and to successfully construct stem cell-derived TED. Microencapsulated VEGF gene-modified hUCMSCs were prepared with the use of a sodium alginate-barium chloride one-step encapsulation technology. Seven days after the transplantation of the stem cell-derived TED and microencapsulated VEGF gene-modified hUCMSCs into the skin defect wounds on the backs of miniature pigs, the VEGF expression increased and the TED had a higher degree of vascularization. Re-epithelialization of the wound was completed after 3 weeks. Microencapsulated VEGF gene-modified hUCMSCs can effectively improve the vascularization of TED and consequently the quality of wound healing. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Simultaneous acute deep vein thrombosis and acute brucellosis. A case report.

PubMed

Salihi, Salih; Andaç, Şeyda; Kalender, Mehmet; Yıldırım, Onur; İmre, Ayfer

2016-06-01

Brucellosis is a zoonotic disease common in developing countries. Vascular complications, including arterial and venous, associated with Brucella infection have rarely been reported. A case of deep venous thrombosis (DVT) developing after a diagnosis of acute brucellosis in a young milkman is presented. A 26-year-old man presented with pain in the right leg. The patient's medical history included a diagnosis of brucellosis in our hospital where he had presented with complaints of weakness and fever. Peripheral venous Doppler ultrasound showed DVT, and the patient was treated with anticoagulants. The patient was discharged with warfarin therapy and anti-brucellosis treatment. Although rare, some infectious agents may cause vascular pathologies. Patients presenting with symptoms of DVT or similar vascular pathologies should be assessed for infectious agents, particularly in those coming from Brucella-endemic areas.

Chlamydia pneumoniae Infection in Atherosclerotic Lesion Development through Oxidative Stress: A Brief Overview

PubMed Central

Di Pietro, Marisa; Filardo, Simone; De Santis, Fiorenzo; Sessa, Rosa

2013-01-01

Chlamydia pneumoniae, an obligate intracellular pathogen, is known as a leading cause of respiratory tract infections and, in the last two decades, has been widely associated with atherosclerosis by seroepidemiological studies, and direct detection of the microorganism within atheroma. C. pneumoniae is presumed to play a role in atherosclerosis for its ability to disseminate via peripheral blood mononuclear cells, to replicate and persist within vascular cells, and for its pro-inflammatory and angiogenic effects. Once inside the vascular tissue, C. pneumoniae infection has been shown to induce the production of reactive oxygen species in all the cells involved in atherosclerotic process such as macrophages, platelets, endothelial cells, and vascular smooth muscle cells, leading to oxidative stress. The aim of this review is to summarize the data linking C. pneumoniae-induced oxidative stress to atherosclerotic lesion development. PMID:23877837

Improved Photodynamic Efficacy of Zn(II) Phthalocyanines via Glycerol Substitution

PubMed Central

Chin, Yunni; Lim, Siang Hui; Zorlu, Yunus; Ahsen, Vefa; Kiew, Lik Voon; Chung, Lip Yong; Dumoulin, Fabienne; Lee, Hong Boon

2014-01-01

Phthalocyanines are excellent photosensitizers for photodynamic therapy as they have strong absorbance in the near infra-red region which is most relevant for in vivo activation in deeper tissular regions. However, most phthalocyanines present two major challenges, ie, a strong tendency to aggregate and low water-solubility, limiting their effective usage clinically. In the present study, we evaluated the potential enhancement capability of glycerol substitution on the photodynamic properties of zinc (II) phthalocyanines (ZnPc). Three glycerol substituted ZnPc, 1–3, (tetra peripherally, tetra non-peripherally and mono iodinated tri non-peripherally respectively) were evaluated in terms of their spectroscopic properties, rate of singlet oxygen generation, partition coefficient (log P), intracellular uptake, photo-induced cytotoxicity and vascular occlusion efficiency. Tetrasulfonated ZnPc (ZnPcS4) was included as a reference compound. Here, we showed that 1–3 exhibited 10–100 nm red-shifted absorption peaks with higher molar absorptivity, and at least two-fold greater singlet oxygen generation rates compared to ZnPcS4. Meanwhile, phthalocyanines 1 and 2 showed more hydrophilic log P values than 3 consistent with the number of glycerol attachments but 3 was most readily taken up by cells compared to the rest. Both phthalocyanines 2 and 3 exhibited potent phototoxicity against MCF-7, HCT-116 and HSC-2 cancer cell-lines with IC50 ranging 2.8–3.2 µM and 0.04–0.06 µM respectively, while 1 and ZnPcS4 (up to 100 µM) failed to yield determinable IC50 values. In terms of vascular occlusion efficiency, phthalocyanine 3 showed better effects than 2 by causing total occlusion of vessels with diameter <70 µm of the chorioallantoic membrane. Meanwhile, no detectable vascular occlusion was observed for ZnPcS4 with treatment under similar experimental conditions. These findings provide evidence that glycerol substitution, in particular in structures 2 and 3, is able to improve the photodynamic properties of ZnPc. PMID:24840576

Improved photodynamic efficacy of Zn(II) phthalocyanines via glycerol substitution.

PubMed

Chin, Yunni; Lim, Siang Hui; Zorlu, Yunus; Ahsen, Vefa; Kiew, Lik Voon; Chung, Lip Yong; Dumoulin, Fabienne; Lee, Hong Boon

2014-01-01

Phthalocyanines are excellent photosensitizers for photodynamic therapy as they have strong absorbance in the near infra-red region which is most relevant for in vivo activation in deeper tissular regions. However, most phthalocyanines present two major challenges, ie, a strong tendency to aggregate and low water-solubility, limiting their effective usage clinically. In the present study, we evaluated the potential enhancement capability of glycerol substitution on the photodynamic properties of zinc (II) phthalocyanines (ZnPc). Three glycerol substituted ZnPc, 1-3, (tetra peripherally, tetra non-peripherally and mono iodinated tri non-peripherally respectively) were evaluated in terms of their spectroscopic properties, rate of singlet oxygen generation, partition coefficient (log P), intracellular uptake, photo-induced cytotoxicity and vascular occlusion efficiency. Tetrasulfonated ZnPc (ZnPcS4) was included as a reference compound. Here, we showed that 1-3 exhibited 10-100 nm red-shifted absorption peaks with higher molar absorptivity, and at least two-fold greater singlet oxygen generation rates compared to ZnPcS4. Meanwhile, phthalocyanines 1 and 2 showed more hydrophilic log P values than 3 consistent with the number of glycerol attachments but 3 was most readily taken up by cells compared to the rest. Both phthalocyanines 2 and 3 exhibited potent phototoxicity against MCF-7, HCT-116 and HSC-2 cancer cell-lines with IC50 ranging 2.8-3.2 µM and 0.04-0.06 µM respectively, while 1 and ZnPcS4 (up to 100 µM) failed to yield determinable IC50 values. In terms of vascular occlusion efficiency, phthalocyanine 3 showed better effects than 2 by causing total occlusion of vessels with diameter <70 µm of the chorioallantoic membrane. Meanwhile, no detectable vascular occlusion was observed for ZnPcS4 with treatment under similar experimental conditions. These findings provide evidence that glycerol substitution, in particular in structures 2 and 3, is able to improve the photodynamic properties of ZnPc.

Survival rates in dysvascular lower limb amputees.

PubMed

Kulkarni, J; Pande, S; Morris, J

2006-01-01

To assess the 5-year and 10-year survival rates of major (above ankle disarticulation level) dysvascular lower limb amputees attending a sub-regional Disablement Services Centre (DSC) specialising in amputee rehabilitation. Also to investigate the association between survival rates, cause of dysvascularity, level of amputation, smoking status and occupational status. The study was undertaken in sub-regional DSC for amputee rehabilitation covering a base population of about 3.5million people. Over 80% of lower limb amputations were done for dysvascularity (peripheral vascular disease, diabetic or combination). All these patients were followed up in the DSC for their prosthetic/amputee rehabilitation. Modular case records of 201 consecutive patients from 1994 to 1995 who had diagnosis of dysvascularity as the cause of major lower limb amputations, were scrutinised regarding their 10-year survival; demographic details, level of lower limb amputations, Above Knee (AK=Transfemoral), Below Knee (BK=Transtibial), smoking status, occupational status, healing of the stump at first assessment, cause of amputation and association of these factors with survival rates. Of 201 individuals with either AK or BK amputations, 60% (121) had AK amputations and 67% (134) were males, the mean age was 69years of age. Sixty-seven percent (97) had history of smoking, either current 43% (62) or prior 24% (35) smoking, and 59% (68) were skilled or non-skilled manual workers. Fifty-one percent (99) had diagnosis of peripheral vascular disease, whilst 34% (65) had combination of peripheral vascular disease and diabetes, diabetes on its own in 4% (7). In 12% (23) other causes were noted such as embolism, acute ischaemia, venous ulcers, etc. Regarding stumps healing at first assessment, healing was noted in 54% (109) whilst stump was unhealed in 46% (92). The median survival was 48months. Using Cox proportional hazards regression to identify association with survival, the hazard ratio (HR) was significant regarding level of amputation: HR 2.34; 95% confidence interval (CI) (1.58, 3.47), P<0.001 (a recent BK amputation increases the risk by 2.3 compared to a recent AK amputation in diabetic cohort and also in the peripheral vascular disease/diabetes cohort). Hazard ratio was less than 1.0 in bilateral amputees: HR 0.35, 95% CI (0.21, 0.60), P<0.001 (bilateral amputation decreases risk by 0.35). Our study indicates that the median survival remains at 4years, which is similar to the previously published evidence in the Finish study of 1998 and the earlier study from Scotland in 1992. Unlike the previous data, our study indicates that patients with BK amputations have a higher hazard ratio than the AK amputees, and an association with diabetes has poorer prognosis regarding survival.

Cost-effectiveness of medical, endovascular and surgical management of peripheral vascular disease☆

PubMed Central

Fanari, Zaher; Weintraub, William S.

2015-01-01

Peripheral arterial disease (PAD) is responsible for 20% of all US hospital admissions. Management of PAD has evolved over time to include many medical and transcatheter interventions in addition to the traditional surgical approach. Non-invasive interventions including supervised exercise programs and antiplatelets use are economically attractive therapies that should be considered in all patients at risk. While surgery offers so far a clinically and economically appropriate option, the improvement of percutaneous transluminal angioplasty (PTA) technique with the addition of drug-coated balloons offers a reasonably clinically and economically attractive alternative that will continue to evolve in the future. PMID:26238266

Positioning Vascularized Composite Allotransplantation in the Spectrum of Transplantation

DTIC Science & Technology

2016-10-01

did not reject the third-party cardiac allografts , but instead rejected the original VCA tissues (Fig. 2, left panel). To test whether RPM impaired...long-term VCA survival, but the rejection of VCA tissues as a result of third party cardiac allografting suggests the incomplete regulation of host...mechanisms contributing to rejection of vascularized composite allografts (VCA) in murine models, and how these may be overcome to promote long-term

Social network composition of vascular patients and its associations with health behavior and clinical risk factors.

PubMed

Heijmans, Naomi; van Lieshout, Jan; Wensing, Michel

2017-01-01

This study aimed to explore linkages of patients' social network composition with health behaviors and clinical risk factors. This observational study was embedded in a project aimed at improving cardiovascular risk management (CRVM) in primary care. 657 vascular patients (227 with cardiovascular disease, 380 at high vascular risk), mean age 72.4 (SD 9.4) years, were recruited as were individuals patients considered important for dealing with their disease, so called alters (n = 487). Network composition was measured with structured patient questionnaires. Both patients and alters completed questionnaires to measure health behavior (habits for physical activity, diet, and smoking). Clinical risk factors (systolic blood pressure, LDL cholesterol level, and body mass index) were extracted from patients' medical records. Six logistic regression analyses, using generalized estimating equations, were used to test three hypothesized effects of network composition (having alters with healthful behaviors, without depression, and with specialized knowledge) on six outcomes, adjusted for demographic, personal and psychological characteristics. Having alters with overall healthful behavior was related to healthful patient diet (OR 2.14, 95%CI: 1.52-3.02). Having non-smoking alters in networks was related to reduced odds for patient smoking (OR 0.17, 95%CI: 0.05-0.60). No effects of presence of non-depressed alters were found. Presence of alters with specialized knowledge on CVRM was inversely related to healthful diet habits of patients (OR 0.47, 95%CI 0.24-0.89). No significant associations between social network composition and clinical risk factors were found. Diet and smoking, but not physical exercise and clinical risk factors, were associated with social network composition of patients with vascular conditions. In this study of vascular patients, controlling for both personal and psychological factors, fewer network influences were found compared to previous research. Further research is needed to examine network structure characteristics as well as the role of psychological factors to enhance understanding health behavior of patients involved in CVRM.

The use of breast ultrasound color Doppler vascular pattern morphology improves diagnostic sensitivity with minimal change in specificity.

PubMed

Svensson, W E; Pandian, A J; Hashimoto, H

2010-10-01

The aim of this study was to evaluate the use of vascular morphology, around and within the B-mode region of abnormality, for improving the diagnostic accuracy of two of the most common solid breast pathologies. The B-mode and Doppler images of 117 breast cancers and 366 fibroadenomas and lesions with a fibroadenoma-like appearance were reviewed retrospectively and the morphology of the vascular pattern was evaluated. The ratio of external to internal color Doppler, the external vascular pattern and the connecting vessels to internal vessels were assessed and differentiated into benign and malignant vascular patterns. These patterns were correlated with the histological diagnosis. Vascularity was demonstrated in 95 % of cancers and in 46 % of benign lesions with a trend to increasing vascularity in cancers. This provided poor specificity for excluding cancer in fibroadenomas. Variations in vascular pattern were recorded. The observed benign vascular patterns were avascularity, vascularity in the periphery and peripheral marginal vessels connecting with internal vascularity. The observed malignant vascular patterns were radially aligned external vessels with internal vessels being more numerous than external vessels which connected to radial vessels. (Fisher exact test p < 0.0001). Analysis of the vascular morphology improved the sensitivity for identifying cancers from 97 % (B-mode) to 99 % (B-mode and color Doppler) with a minimal reduction in specificity (93.7 to 92.6 %) or accuracy (94.6 to 94.2 %). The presence of vascularity within a lesion, by itself, is no longer a good predictor of malignancy because of the increase in Doppler sensitivity associated with improvements in ultrasound technology. The color Doppler ultrasound vascular pattern morphology improves the accuracy and sensitivity of B-mode image diagnosis, breast cancers and fibroadenomas with a minimal loss of specificity. Any breast lesion with radial rather than marginal connecting vessels should be regarded with suspicion. © Georg Thieme Verlag KG Stuttgart · New York.

Agmatine suppresses peripheral sympathetic tone by inhibiting N-type Ca(2+) channel activity via imidazoline I2 receptor activation.

PubMed

Kim, Young-Hwan; Jeong, Ji-Hyun; Ahn, Duck-Sun; Chung, Seungsoo

2016-08-26

Agmatine, a putative endogenous ligand of imidazoline receptors, suppresses cardiovascular function by inhibiting peripheral sympathetic tone. However, the molecular identity of imidazoline receptor subtypes and its cellular mechanism underlying the agmatine-induced sympathetic suppression remains unknown. Meanwhile, N-type Ca(2+) channels are important for the regulation of NA release in the peripheral sympathetic nervous system. Therefore, it is possible that agmatine suppresses NA release in peripheral sympathetic nerve terminals by inhibiting Ca(2+) influx through N-type Ca(2+) channels. We tested this hypothesis by investigating agmatine effect on electrical field stimulation (EFS)-evoked contraction and NA release in endothelium-denuded rat superior mesenteric arterial strips. We also investigated the effect of agmatine on the N-type Ca(2+) current in superior cervical ganglion (SCG) neurons in rats. Our study demonstrates that agmatine suppresses peripheral sympathetic outflow via the imidazoline I2 receptor in rat mesenteric arteries. In addition, the agmatine-induced suppression of peripheral vascular sympathetic tone is mediated by modulating voltage-dependent N-type Ca(2+) channels in sympathetic nerve terminals. These results suggest a potential cellular mechanism for the agmatine-induced suppression of peripheral sympathetic tone. Furthermore, they provide basic and theoretical information regarding the development of new agents to treat hypertension. Copyright © 2016 Elsevier Inc. All rights reserved.

Addition of Autologous Mesenchymal Stem Cells to Whole Blood for Bio-Enhanced ACL Repair has No Benefit in the Porcine Model

PubMed Central

Proffen, Benedikt L.; Vavken, Patrick; Haslauer, Carla M.; Fleming, Braden C.; Harris, Chad E.; Machan, Jason T.; Murray, Martha M.

2015-01-01

Background Co-culture of mesenchymal stem cells (MSCs) from the retropatellar fat pad and peripheral blood has been shown to stimulate anterior cruciate ligament (ACL) fibroblast proliferation and collagen production in vitro. Current techniques of bio-enhanced ACL repair in animal studies involve adding a biologic scaffold, in this case an extracellular matrix based scaffold saturated with autologous whole blood, to a simple suture repair of the ligament. Whether the enrichment of whole blood with MSCs would further improve the in vivo results of bio-enhanced ACL repair was investigated. Hypothesis/Purpose The hypothesis was that the addition of MSCs derived from adipose tissue or peripheral blood to the blood-extracellular matrix composite, which is used in bio-enhanced ACL repair to stimulate healing, would improve the biomechanical properties of a bio-enhanced ACL repair after 15 weeks of healing. Study Design Controlled laboratory study. Methods Twenty-four adolescent Yucatan mini-pigs underwent ACL transection followed by: 1) bio-enhanced ACL repair, 2) bio-enhanced ACL repair with the addition of autologous adipose-derived MSCs and 3) bio-enhanced ACL repair with the addition of autologous peripheral blood derived MSCs. After fifteen weeks of healing, structural properties of the ACL (yield & failure load, linear stiffness) were measured. Cell and vascular density were measured in the repaired ACL via histology, and its tissue structure was qualitatively evaluated using the Advanced Ligament Maturity Index. Results After fifteen weeks of healing, there were no significant improvements in the biomechanical or histological properties with the addition of adipose-derived MSCs. The only significant change with the addition of peripheral blood MSCs was an increase in knee anteroposterior (AP) laxity when measured at 30 degrees of flexion. Conclusions These findings suggest that the addition of adipose or peripheral blood MSCs to whole blood prior to saturation of an extracellular matrix carrier with the blood did not improve the functional results of bio-enhanced ACL repair after 15 weeks of healing in the pig model. Clinical Relevance Whole blood represents a practical biologic additive to ligament repair, and any other additive (including stem cells) should be demonstrated to be superior to this baseline before clinical use is considered. PMID:25549633

Inflammation markers and prediction of post-stroke vascular disease recurrence: the MITICO study.

PubMed

Castillo, J; Alvarez-Sabín, J; Martínez-Vila, E; Montaner, J; Sobrino, T; Vivancos, J

2009-02-01

Vascular disease recurrence following stroke is the main cause of morbidity and mortality. The MITICO study was designed to assess the prognostic value of markers of inflammation in relation to the risk of recurrence of vascular disease. Multi-centered prospective observational study, in patients with ischemic stroke not receiving anti-coagulation therapy and who were recruited within 1-3 months from stroke onset. Blood samples were obtained at baseline and follow- up for the determination of high-sensitive C reactive protein (CRP), IL-6, IL-10, ICAM-1, VCAM- 1, MMP-9 and cellular fibronectin. Four follow-up visits within the first year were to rule out recurrence. Of 965 patients from 65 hospitals, 780 (aged 67.5+/-11.2 years, 33.6 % female) were valid for main analysis. One-hundred and three patients (13.2 %) had a new adverse vascular event and 116 patients (14.9 %) a vascular event or vascular death (66.4 % stroke, 21.5 % coronary and 12.1 % peripheral). Levels of IL-6 > 5 pg/mL and VCAM-1 > 1350 ng/mL (ROC curve analyses) were associated with vascular disease recurrence risk (OR: 28.7; 95 % CI: 14.2-58.0 vs. OR: 4.1; 95 % CI: 2.4-7.1, respectively) following adjustment for confounding variables. Risk of adverse vascular event or death from vascular disease were associated with IL-6 (OR: 21.2; 95 % CI: 11.6-38.7) and VCAM-1 (OR: 3.8; 95 % CI: 2.3-6.4). Baseline values of IL-6 > 5 pg/mL and VCAM-1 > 1350 ng/mL increase 21-fold and 4-fold, respectively, the risk of new vascular disease event or death from vascular disease in patients with ischemic stroke not receiving anti-coagulation treatment.

Insulin sensitizers prevent fine particulate matter-induced vascular insulin resistance and changes in endothelial progenitor cell homeostasis.

PubMed

Haberzettl, Petra; McCracken, James P; Bhatnagar, Aruni; Conklin, Daniel J

2016-06-01

Exposure to fine particular matter (PM2.5) increases the risk of developing cardiovascular disease and Type 2 diabetes. Because blood vessels are sensitive targets of air pollutant exposure, we examined the effects of concentrated ambient PM2.5 (CAP) on vascular insulin sensitivity and circulating levels of endothelial progenitor cells (EPCs), which reflect cardiovascular health. We found that CAP exposure for 9 days decreased insulin-stimulated Akt phosphorylation in the aorta of mice maintained on control diet. This change was accompanied by the induction of IL-1β and increases in the abundance of cleaved IL-18 and p10 subunit of Casp-1, consistent with the activation of the inflammasome pathway. CAP exposure also suppressed circulating levels of EPCs (Flk-1(+)/Sca-1(+) cells), while enhancing the bone marrow abundance of these cells. Although similar changes in vascular insulin signaling and EPC levels were observed in mice fed high-fat diet, CAP exposure did not exacerbate diet-induced changes in vascular insulin resistance or EPC homeostasis. Treatment with an insulin sensitizer, metformin or rosiglitazone, prevented CAP-induced vascular insulin resistance and NF-κB and inflammasome activation and restored peripheral blood and bone marrow EPC levels. These findings suggest that PM2.5 exposure induces diet-independent vascular insulin resistance and inflammation and prevents EPC mobilization, and that this EPC mobilization defect could be mediated by vascular insulin resistance. Impaired vascular insulin sensitivity may be an important mechanism underlying PM2.5-induced vascular injury, and pharmacological sensitization to insulin action could potentially prevent deficits in vascular repair and mitigate vascular inflammation due to exposure to elevated levels of ambient air pollution. Copyright © 2016 the American Physiological Society.

Effects of snake venom from Saudi cobras and vipers on hormonal levels in peripheral blood.

PubMed

Abdel-Galil, Khidir A; Al-Hazimi, Awdah M

2004-08-01

Knowledge about the effects of snake venoms on endocrine glands in the Kingdom of Saudi Arabia (KSA) is meager. The aim of the present study is to investigate the acute and chronic envenomation from 4 snakes out of 8 species of Saudi Cobras and Vipers on the tissues of endocrine glands and peripheral hormonal levels in male rats. The peripheral blood levels of 4 hormones mainly testosterone, cortisol, insulin and thyroxin were investigated in male Wistar rats following acute and chronic treatment of the rats with poisonous snake venoms at the Department of Physiology, Faculty of Medicine, King Abdul-Aziz University, Jeddah, Kingdom of Saudi Arabia between September 2000 to May 2001. Using radio immunoassay for hormonal analysis, a rise in testosterone levels in peripheral blood was obtained following acute treatment, which is due to the effect of the venoms on vascular permeability and increased blood flow. In contrast, the chronic treatment with venoms resulted in a delayed effect on vascular permeability and testicular degeneration resulting in a decreased blood flow and a significant drop in testosterone concentration. Cortisol levels were no different from the controls during acute treatment but it demonstrates gradual rise following chronic treatment to withstand the stress imposed on the animals. Similar results were obtained for insulin, which showed normal values with acute treatment but decreased levels of chronic treatment suggesting insulin insufficiently. Likewise, the thyroxin levels were decreased with chronic treatment suggesting a toxic effect of the poison on the rich blood supply of the thyroid follicles with a subsequent decrease in blood flow to the tissues and therefore, decreased thyroid hormone levels. The effects of venom toxicity on testosterone levels were either normal or stimulatory with acute treatment or inhibitory with chronic treatment depending on the vascular blood flow and testicular degeneration. Cortisol levels were normal at acute treatment but showed a gradual rise reflecting the stress imposed on the animals. The rise in cortisol levels was visualized to potentiate the cardiovascular and metabolic changes. The effects on insulin and thyroxin were similar to those of testosterone level showing normal or stimulatory effect with acute treatment followed by decreased levels of hormones with chronic treatment.

Evaluation of a static stretching intervention on vascular endothelial function and arterial stiffness.

PubMed

Shinno, Hiromi; Kurose, Satoshi; Yamanaka, Yutaka; Higurashi, Kyoko; Fukushima, Yaeko; Tsutsumi, Hiromi; Kimura, Yutaka

2017-06-01

Maintenance and enhancement of vascular endothelial function contribute to the prevention of cardiovascular disease and prolong a healthy life expectancy. Given the reversible nature of vascular endothelial function, interventions to improve this function might prevent arteriosclerosis. Accordingly, we studied the effects of a 6-month static stretching intervention on vascular endothelial function (reactive hyperaemia peripheral arterial tonometry index: RH-PAT index) and arterial stiffness (brachial-ankle pulse wave velocity: baPWV) and investigated the reversibility of these effects after a 6-month detraining period following intervention completion. The study evaluated 22 healthy, non-smoking, premenopausal women aged ≥40 years. Subjects were randomly assigned to the full-intervention (n = 11; mean age: 48.6 ± 2.8 years) or a half-intervention that included a control period (n = 11; mean age: 46.9 ± 3.6 years). Body flexibility and vascular endothelial function improved significantly after 3 months of static stretching. In addition to these improvements, arterial stiffness improved significantly after a 6-month intervention. However, after a 6-month detraining period, vascular endothelial function, flexibility, and arterial stiffness all returned to preintervention conditions, demonstrating the reversibility of the obtained effects. A 3-month static stretching intervention was found to improve vascular endothelial function, and an additional 3-month intervention also improved arterial stiffness. However, these effects were reversed by detraining.

Reduced H3K27me3 expression in radiation-associated angiosarcoma of the breast.

PubMed

Mentzel, Thomas; Kiss, Katalin

2018-03-01

The diagnosis of radiation-associated angiosarcoma is challenging and there are overlapping clinicopathological features between radiation-associated benign, atypical and malignant vascular lesions. It has been shown convincingly, that the majority of radiation-associated angiosarcomas are characterised by amplification and subsequent overexpression of MYC in contrast to benign and atypical vascular lesions. Given the fact that epigenetic changes play an important role in carcinogenesis and loss of histone H3K27 trimethylation (H3K27me3) has been found in a number of malignant neoplasms including malignant peripheral nerve sheath tumours, especially when associated with previous radiotherapy, we evaluated the immunohistochemical reaction pattern for H3K27me3 in 49 vascular lesions and control cases: normal skin and benign vascular lesions not associated with previous radiotherapy, radiation-associated benign, atypical and malignant vascular lesions and angiosarcomas not associated with previous radiotherapy. We found loss of H3K27me3 expression in most cases of radiation-associated angiosarcomas, whereas endothelial cells in benign and atypical vascular lesions arising after previous radiotherapy stained positively for H3K27me3. The sporadic angiosarcomas stained inconsistently for H3K27me3. Loss of H3K27me3 is typically seen in radiation-associated angiosarcomas, representing an additional diagnostic tool and raises questions in regard to the carcinogenesis of malignant vascular neoplasms.

Local Drug Delivery to Prevent Restenosis

PubMed Central

Seedial, Stephen M.; Ghosh, Soumojit; Saunders, R. Scott; Suwanabol, Pasithorn A.; Shi, Xudong; Liu, Bo; Kent, K. Craig

2013-01-01

Introduction Despite significant advances in vascular biology, bioengineering and pharmacology, restenosis remains a limitation to the overall efficacy of vascular reconstructions, both percutaneous and open. Although the pathophysiology of intimal hyperplasia is complex, a number of drugs and/or molecular tools have been identified that can prevent restenosis. Moreover, the focal nature of this process lends itself to treatment with local drug administration. In this article we provide a broad overview of current and future techniques for local drug delivery that have been developed to prevent restenosis following vascular intervention. Methods A systematic electronic literature search using PubMed was performed for all accessible published articles through September 2012. In an effort to remain current, additional searches were performed for abstracts presented at relevant societal meetings, filed patents, clinical trials and funded NIH awards. Results The efficacy of local drug delivery has been demonstrated in the coronary circulation with the current clinical use of drug-eluting stents (DES). Until recently, however, DES were not found to be efficacious in the peripheral circulation. Further pursuit of intraluminal devices has led to the development of balloon-based technologies with a recent surge in trials involving drug-eluting balloons. Early data appears encouraging, particularly for treatment of lesions in the superficial femoral artery, with several devices having recently received the CE mark in Europe. Investigators have also explored periadventitial application of biomaterials containing anti-restenotic drugs, an approach that could be particularly useful for surgical bypass or endarterectomy. In the past systemic drug delivery has been unsuccessful, however, there has been recent exploration of intravenous delivery of drugs designed specifically to target injured or reconstructed arteries. Our review revealed a multitude of additional interesting strategies including more than 65 new patents issued over the past two years for approaches to local drug delivery focused on preventing restenosis. Conclusion Restenosis following intraluminal or open vascular reconstruction remains an important clinical problem. Success in the coronary circulation has not translated into solutions for the peripheral arteries. However, our review of the literature reveals a number of promising approaches including drug-eluting balloons, periadventitial drug delivery as well as targeted systemic therapies. These innovations as well as others suggest that the future is bright and a solution for preventing restenosis in peripheral vessels will soon be at hand. PMID:23601595

Towards the therapeutic use of vascular smooth muscle progenitor cells.

PubMed

Merkulova-Rainon, Tatyana; Broquères-You, Dong; Kubis, Nathalie; Silvestre, Jean-Sébastien; Lévy, Bernard I

2012-07-15

Recent advances in the development of alternative proangiogenic and revascularization processes, including recombinant protein delivery, gene therapy, and cell therapy, hold the promise of greater efficacy in the management of cardiovascular disease in the coming years. In particular, vascular progenitor cell-based strategies have emerged as an efficient treatment approach to promote vessel formation and repair and to improve tissue perfusion. During the past decade, considerable progress has been achieved in understanding therapeutic properties of endothelial progenitor cells, while the therapeutic potential of vascular smooth muscle progenitor cells (SMPC) has only recently been explored; the number of the circulating SMPC being correlated with cardiovascular health. Several endogenous SMPC populations with varying phenotypes have been identified and characterized in the peripheral blood, bone marrow, and vascular wall. While the phenotypic entity of vascular SMPC is not fully defined and remains an evolving area of research, SMPC are increasingly recognized to play a special role in cardiovascular biology. In this review, we describe the current approaches used to define vascular SMPC. We further summarize the data on phenotype and functional properties of SMPC from various sources in adults. Finally, we discuss the role of SMPC in cardiovascular disease, including the contribution of SMPC to intimal proliferation, angiogenesis, and atherosclerotic plaque instability as well as the benefits resulting from the therapeutic use of SMPC.

Can vascular risk factors influence number and size of cerebral metastases? A 3D-MRI study in patients with different tumor entities.

PubMed

Nagel, Sandra; Berk, Benjamin-Andreas; Kortmann, Rolf-Dieter; Hoffmann, Karl-Titus; Seidel, Clemens

2018-02-01

There is increasing evidence that cerebral microangiopathy reduces number of brain metastases. Aim of this study was to analyse if vascular risk factors (arterial hypertension, diabetes mellitus, smoking, and hypercholesterolemia) or the presence of peripheral arterial occlusive disease (PAOD) can have an impact on number or size of brain metastases. 200 patients with pre-therapeutic 3D-brain MRI and available clinical data were analyzed retrospectively. Mean number of metastases (NoM) and mean diameter of metastases (mDM) were compared between patients with/without vascular risk factors (vasRF). No general correlation of vascular risk factors with brain metastases was found in this monocentric analysis of a patient cohort with several tumor types. Arterial hypertension, diabetes mellitus, hypercholesterolemia and smoking did not show an effect in uni- and multivariate analysis. In patients with PAOD the number of BM was lower than without PAOD. This was the case independent from cerebral microangiopathy but did not persist in multivariate analysis. From this first screening approach vascular risk factors do not appear to strongly influence brain metastasation. However, larger prospective multi-centric studies with better characterized severity of vascular risk are needed to more accurately detect effects of individual factors. Copyright © 2018 Elsevier B.V. All rights reserved.

Contribution of central and peripheral adaptations to changes in VO₂max following four weeks of sprint interval training.

PubMed

Raleigh, James P; Giles, Matthew D; Islam, Hashim; Nelms, Matthew William; Bentley, Robert F; Jones, Joshua H; Neder, J Alberto; Boonstra, Kristen; Quadrilatero, Joe; Simpson, Craig A; Tschakovsky, Michael E; Gurd, Brendon J

2018-05-07

The current study examined the contribution of central and peripheral adaptations to changes in maximal oxygen uptake (VO₂max) following sprint interval training (SIT). Twenty-three males completed four weekly SIT sessions (8 x 20 second cycling bouts at ~170% of work rate at VO₂max, 10 second recovery) for four weeks. Following completion of training, the relationship between changes in VO₂max and changes in central (cardiac output) and peripheral (a-vO₂diff, muscle capillary density, oxidative capacity, fibre-type distribution) adaptations was determined in all participants using correlation analysis. Participants were then divided in to tertiles based on the magnitude of their individual VO₂max responses and differences in central/peripheral adaptations were examined in the top (HI; ~10 mL/kg/min increase in VO₂max, p<0.05) and bottom (LO; no change in VO₂max, p>0.05) tertiles (n=8 each). Training had no impact on Qmax and no differences were observed between the LO and HI groups (p>0.05). A-vO₂diff increased in the HI group only (p<0.05) and correlated significantly (r=0.71, p<0.01) with changes in VO₂max across all participants. Muscle capillary density (p<0.02) and ß-hydroxyacyl-CoA dehydrogenase maximal activity (p<0.05) increased in both groups, with no between-group differences (p>0.05). Citrate synthase maximal activity (p<0.01) and type IIA fibre composition (p<0.05) increased in the LO group only. Collectively, while the heterogeneity in the observed VO₂max response following four weeks of SIT appears to be attributable to individual differences in systemic vascular and/or muscular adaptations, the markers examined in the current study were unable to explain the divergent VO₂max responses in the LO and HI groups.

Blindness, Diabetes, and Amputation: Alleviation of Depression and Pain through Thermal Biofeedback Therapy.

ERIC Educational Resources Information Center

Needham, W. E.; And Others

1993-01-01

A 39-year-old man who was blind, diabetic, and had a double amputation with chronic renal failure and peripheral vascular disease was treated with thermal biofeedback to reduce his depression through increased self-control, to minimize pain, and to facilitate healing of a pregangrenous hand. On treatment discharge, his mental and physical states…

Using Machine-Learned Bayesian Belief Networks to Predict Perioperative Risk of Clostridium Difficile Infection Following Colon Surgery

DTIC Science & Technology

2012-01-01

resections without C-Diff (n = 111,368) General characteristics 8500 (7.5).06116 (6.3)8384 (7.5)CM_HYPOTHY ( Hypothyroidism ) 1772 (1.6).04839 (2.1)1733 (1.6...CM_COAG), hypothyroidism (CM_HYPOTHY), liver disease (CM_LIVER), neurological disorders (CM_NEURO), paralysis (CM_PARA), peripheral vascular disorders

Phenotypic heterogeneity associated with a novel mutation (Gly112Glu) in the Norrie disease protein.

PubMed

Allen, R C; Russell, S R; Streb, L M; Alsheikheh, A; Stone, E M

2006-02-01

To determine the molecular pathology and clinical severity of two pedigrees with a history of early retinal detachment and peripheral retinal vascular abnormalities. Longitudinal cohort study. A longitudinal clinical study and DNA analysis was performed on 49 family members of two pedigrees. Nine individuals were found to be hemizygous for a mutation at codon 112 (Gly112Glu) of the Norrie disease protein (NDP) in one pedigree. Significant phenotypic heterogeneity was found. The proband presented with a unilateral subtotal retinal detachment at the age of 3 years, and subsequently developed a slowly progressive tractional retinal detachment involving the macula in the contralateral eye at the age of 4 years. One individual had only mild peripheral retinal pigmentary changes with normal vision at the age of 79 years. The remaining seven individuals had varying degrees of peripheral retinal vascular abnormalities and anterior segment findings. Seven affected members of a second pedigree affected by a previously reported mutation, Arg74Cys, also demonstrated wide ocular phenotypic variation. A novel mutation (Gly112Glu), which represents the most carboxy located, NDP mutation reported, results in significant phenotypic heterogeneity. These data support the contention that the spectrum of ocular disease severity associated with these NDP mutations is broad. Use of terms that characterize this entity by phenotypic appearance, such as familial exudative vitreoretinopathy, do not adequately communicate the potential spectrum of severity of this disorder to affected or carrier family members.

Improving Peripheral and Central Vascular Adjustments during Exercise through a Training Program in Adolescents with Obesity.

PubMed

Julian, Valérie; Thivel, David; Pereira, Bruno; Costes, Frédéric; Richard, Ruddy; Duclos, Martine

2016-01-01

The effects of a training program (TP) on muscle microvascularization during exercise remained to be explored in adolescents with obesity. We hypothesized that a TP would lead to better microvascular adaptations to exercise in skeletal muscle. 15 inactive adolescents followed a 12-week TP where both peripheral (muscular microvascularization) and central (cardiac) adaptations to exercise (40 min exercise set at 70% V̇O2peak) were assessed before and after intervention. Microvascular adaptations were evaluated in the Musculus vastus lateralis with near-infrared spectroscopy, by measurement of muscular blood volume (IR-BV) and tissue oxygen saturation (IR-SO2). Central adaptations were evaluated using thoracic impedance. The TP favored lower BMI (p < 0.001), lower total and abdominal fat (p < 0.001), and a trend for the decrease in insulin resistance index (p = 0.07). V̇O2peak relative to weight (p = 0.008) and maximum power output increased (p = 0.0003). A smaller initial drop in IR-BV and IR-SO2 (p < 0.001), a prompter return of these parameters to their base values, and a higher IR-BV and IR-SO2 all times taken together (p < 0.001) were observed after completing the TP. Concerning central adaptation, cardiac output decreased (p < 0.001). We demonstrate for the first time by noninvasive techniques that a training program induces peripheral and central vascular adaptations to exercise in adolescents with obesity. © 2016 The Author(s) Published by S. Karger GmbH, Freiburg.

Baroreflex Responses to Acute Changes in Blood Volume in Humans

NASA Technical Reports Server (NTRS)

Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

1990-01-01

To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro- reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationships of the cardiopulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venotis Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). Altered vascular volume had no effect on response relations of the carotid-cardiac baroreflex but did alter the gain of the cardiopulmonary baroreflex (-7.93 q 1.71, -4.36 q 1.38, and -2.56 q 1.59 peripheral resistance units/mmHg for hypovolemic, normovolemic, and hypervolemic, respectively) independent of shifts in baseline FVR and PVP. These results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulnionary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

Impaired Production and Diurnal Regulation of Vascular RvDn-3 DPA Increase Systemic Inflammation and Cardiovascular Disease.

PubMed

Colas, Romain A; Souza, Patricia R; Walker, Mary E; Burton, Maudrian; Zasłona, Zbigniew; Curtis, Annie M; Marques, Raquel M; Dalli, Jesmond

2018-03-16

Diurnal mechanisms are central to regulating host responses. Recent studies uncovered a novel family of mediators termed as specialized proresolving mediators that terminate inflammation without interfering with the immune response. Herein, we investigated the diurnal regulation of specialized proresolving mediators in humans and their role in controlling peripheral blood leukocyte and platelet activation. Using lipid mediator profiling and healthy volunteers, we found that plasma concentrations of n-3 docosapentaenoic acid-derived D-series resolvins (RvD n-3 DPA ) were regulated in a diurnal manner. The production and regulation of these mediators was markedly altered in patients at risk of myocardial infarct. These changes were associated with decreased 5-lipoxygenase expression and activity, as well as increased systemic adenosine concentrations. We also found a significant negative correlation between plasma RvD n-3 DPA and markers of platelet, monocyte, and neutrophil activation, including CD63 and CD11b. Incubation of RvD n-3 DPA with peripheral blood from healthy volunteers and patients with cardiovascular disease significantly and dose-dependently decreased platelet and leukocyte activation. Furthermore, administration of RvD5 n-3 DPA to ApoE -/- (apolipoprotein E deficient) mice significantly reduced platelet-leukocyte aggregates, vascular thromboxane B 2 concentrations, and aortic lesions. These results demonstrate that peripheral blood RvD n-3 DPA are diurnally regulated in humans, and dysregulation in the production of these mediators may lead to cardiovascular disease. © 2018 The Authors.

UKPDS 59: hyperglycemia and other potentially modifiable risk factors for peripheral vascular disease in type 2 diabetes.

PubMed

Adler, Amanda I; Stevens, Richard J; Neil, Andrew; Stratton, Irene M; Boulton, Andrew J M; Holman, Rury R

2002-05-01

To determine the role of hyperglycemia in prospective analyses of peripheral vascular disease (PVD) in type 2 diabetes, taking into account other potential risk factors. Potential risk factors for the development of PVD were examined in 3,834 of 5,102 individuals enrolled in the U.K. Prospective Diabetes Study (UKPDS) without PVD at diagnosis of diabetes, followed for 6 years, and for whom relevant data were available. PVD was defined as two of the following: ankle-arm blood pressure index < 0.8, absence of both dorsalis pedis and posterior tibial pulses to palpation in one or both legs, and intermittent claudication. Logistic regression was used to estimate the association between potential risk factors measured 3-4 months after diagnosis of diabetes and incident PVD. The prevalence of PVD at 3-year intervals to 18 years was determined. Hyperglycemia, assessed as HbA(1c), was associated with an increased risk for incident PVD, independent of other risk factors including age, increased systolic blood pressure, reduced HDL cholesterol, smoking, prior cardiovascular disease, peripheral sensory neuropathy, and retinopathy. Each 1% increase in HbA(1c) was associated with a 28% increased risk of PVD (95% CI 12-46), and each 10-mmHg increase in systolic blood pressure with a 25% increase in risk (95% CI 10-43). Hyperglycemia, as well as smoking, dyslipidemia, and blood pressure are potentially modifiable risk factors for the development of PVD.

Real time imaging of peripheral nerve vasculature using optical coherence angiography

NASA Astrophysics Data System (ADS)

Vasudevan, Srikanth; Kumsa, Doe; Takmakov, Pavel; Welle, Cristin G.; Hammer, Daniel X.

2016-03-01

The peripheral nervous system (PNS) carries bidirectional information between the central nervous system and distal organs. PNS stimulation has been widely used in medical devices for therapeutic indications, such as bladder control and seizure cessation. Investigational uses of PNS stimulation include providing sensory feedback for improved control of prosthetic limbs. While nerve safety has been well documented for stimulation parameters used in marketed devices, novel PNS stimulation devices may require alternative stimulation paradigms to achieve maximum therapeutic benefit. Improved testing paradigms to assess the safety of stimulation will expedite the development process for novel PNS stimulation devices. The objective of this research is to assess peripheral nerve vascular changes in real-time with optical coherence angiography (OCA). A 1300-nm OCA system was used to image vasculature changes in the rat sciatic nerve in the region around a surface contacting single electrode. Nerves and vasculature were imaged without stimulation for 180 minutes to quantify resting blood vessel diameter. Walking track analysis was used to assess motor function before and 6 days following experiments. There was no significant change in vessel diameter between baseline and other time points in all animals. Motor function tests indicated the experiments did not impair functionality. We also evaluated the capabilities to image the nerve during electrical stimulation in a pilot study. Combining OCA with established nerve assessment methods can be used to study the effects of electrical stimulation safety on neural and vascular tissue in the periphery.

Amplatzer vascular plug for arteriovenous hemodialysis access occlusion: initial experience.

PubMed

Bui, J T; Gaba, R C; Knuttinen, M G; West, D L; Owens, C A

2009-01-01

The Amplatzer Vascular Plug (AVP; AGA Medical, Golden Valley, MN) is a recently developed self-expanding metallic device indicated for peripheral vascular embolizations. Herein, we describe use of this device in the treatment of vascular complications related to arteriovenous hemodialysis fistulas and grafts. This HIPAA compliant retrospective study was approved by the institutional review board with informed consent waived. Six patients with problematic arteriovenous access underwent access occlusion using the AVP. Procedure indications included vascular steal syndrome in five patients, and enlarging vascular aneurysms in one patient. Contraindications for surgical correction were determined by the referring surgeon. AVP embolizations were performed using devices oversized by 50% introduced through vascular sheaths positioned within vein segments just beyond the arteriovenous anastomoses. Noninvasive evaluation of the involved extremity was performed pre- and post-embolization in addition to clinical follow-up examinations. Measured outcomes included success of angiographic occlusion, improvement in distal arterial flow, AVP number, AVP diameter, time to access occlusion, and clinical symptomatic improvement. Technical success was 100%, with complete arteriovenous access occlusion accomplished in all cases, with an average of 1.5 AVPs used per patient. Mean time to access occlusion was 19.3 minutes. Angiographic improvement in distal arterial flow was immediately evident and resolution of clinical symptoms occurred in all patients, with mean long-term follow-up of 16 months. No procedure-related complications were encountered. The Amplatzer Vascular Plug provides a minimally invasive and efficacious method for embolization of problematic arteriovenous hemodialysis access.

Ultrasound-guided, percutaneous peripheral nerve stimulation: technical note.

PubMed

Chan, Isaac; Brown, Anthony R; Park, Kenneth; Winfree, Christopher J

2010-09-01

Peripheral nerve stimulation is a form of neuromodulation that applies electric current to peripheral nerves to induce stimulation paresthesias within the painful areas. To report a method of ultrasound-guided, percutaneous peripheral nerve stimulation. This technique utilizes real-time imaging to avoid injury to adjacent vascular structures during minimally invasive placement of peripheral nerve stimulator electrodes. We describe a patient that presented with chronic, bilateral foot pain following multiple foot surgeries, for whom a comprehensive, pain management treatment strategy had failed. We utilized ultrasound-guided, percutaneous tibial nerve stimulation at a thigh level to provide durable pain relief on the right side, and open peripheral nerve stimulation on the left. The patient experienced appropriate stimulation paresthesias and excellent pain relief on the plantar aspect of the right foot with the percutaneous electrode. On the left side, we were unable to direct the stimulation paresthesias to the sole of the foot, despite multiple electrode repositionings. A subsequent, open placement of a left tibial nerve stimulator was performed. This revealed that the correct electrode position against the tibial nerve was immediately adjacent to the popliteal artery, and was thus not appropriate for percutaneous placement. We describe a method of ultrasound-guided peripheral nerve stimulation that avoids the invasiveness of electrode placement via an open procedure while providing excellent pain relief. We further describe limitations of the percutaneous approach when navigating close to large blood vessels, a situation more appropriately managed with open peripheral nerve stimulator placement. Ultrasound-guided placement may be considered for patients receiving peripheral nerve stimulators placed within the deep tissues, and not easily placed in a blind fashion.

Renal Artery Stenosis in Patients with Peripheral Artery Disease: Prevalence, Risk Factors and Long-term Prognosis.

PubMed

Aboyans, V; Desormais, I; Magne, J; Morange, G; Mohty, D; Lacroix, P

2017-03-01

The objective was to determine the prevalence and clinical determinants of renal artery stenosis (RAS) in patients undergoing digital subtraction angiography (DSA) for the assessment of peripheral artery disease (PAD), and to evaluate its prognostic significance. All DSAs performed from January 2000 to January 2006 were retrospectively reviewed for assessment of PAD in patients naive for any prior revascularisation of lower-limb arteries. All DSA studies were read by two senior physicians blinded to outcome, and consensus was reached in cases of disagreement. RAS was defined as the presence of ≥50% stenosis in either renal artery. Patients' electronic medical files were systematically reviewed and follow-up was completed by contact with family physicians until January 2014. The primary outcome was composite, including death, peripheral revascularisation, or any limb amputation. Secondary outcomes were all-cause mortality, and another composite, including death and non-fatal myocardial infarction or stroke or coronary or carotid revascularisation. In total, 400 consecutive patients having a first DSA of lower extremities, two thirds of whom were for critical limb ischaemia, were studied. Thirteen patients were excluded owing to poor renal artery imaging. RAS was detected in 57 patients (14%). Only two factors were independently and significantly associated with RAS in multivariate analysis: diffuse PAD (involving both proximal and distal segments [odds ratio {OR} 3.50, 95% confidence interval {CI} 1.16-10.54; p = .026]) and decreased glomerular filtration rate (OR 0.55 per 30 mL/minute/1.73 m 2 , 95% CI 0.41-0.75; p < .001). During follow-up (mean ± SD 62 ± 47 months), 25% experienced limb amputation and 54% died. In multivariate analysis, no significant association was found between RAS and primary outcome (hazard ratio 0.80; 95% CI 0.57-1.10). No significant association was found with secondary outcomes. Incidental RAS is frequent (14%) among patients with PAD undergoing lower extremity imaging. No difference in outcome in patients with RAS versus those without RAS was seen. Larger studies are necessary to draw definite conclusions. Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Quantitative analysis for peripheral vascularity assessment based on clinical photoacoustic and ultrasound images

NASA Astrophysics Data System (ADS)

Murakoshi, Dai; Hirota, Kazuhiro; Ishii, Hiroyasu; Hashimoto, Atsushi; Ebata, Tetsurou; Irisawa, Kaku; Wada, Takatsugu; Hayakawa, Toshiro; Itoh, Kenji; Ishihara, Miya

2018-02-01

Photoacoustic (PA) imaging technology is expected to be applied to clinical assessment for peripheral vascularity. We started a clinical evaluation with the prototype PA imaging system we recently developed. Prototype PA imaging system was composed with in-house Q-switched Alexandrite laser system which emits short-pulsed laser with 750 nm wavelength, handheld ultrasound transducer where illumination optics were integrated and signal processing for PA image reconstruction implemented in the clinical ultrasound (US) system. For the purpose of quantitative assessment of PA images, an image analyzing function has been developed and applied to clinical PA images. In this analyzing function, vascularity derived from PA signal intensity ranged for prescribed threshold was defined as a numerical index of vessel fulfillment and calculated for the prescribed region of interest (ROI). Skin surface was automatically detected by utilizing B-mode image acquired simultaneously with PA image. Skinsurface position is utilized to place the ROI objectively while avoiding unwanted signals such as artifacts which were imposed due to melanin pigment in the epidermal layer which absorbs laser emission and generates strong PA signals. Multiple images were available to support the scanned image set for 3D viewing. PA images for several fingers of patients with systemic sclerosis (SSc) were quantitatively assessed. Since the artifact region is trimmed off in PA images, the visibility of vessels with rather low PA signal intensity on the 3D projection image was enhanced and the reliability of the quantitative analysis was improved.

Epidemiological perspective on infections in chronic dialysis patients.

PubMed

Bloembergen, W E; Port, F K

1996-07-01

Infectious complications are a source of substantial morbidity and a common cause of death among dialysis patients. This article considers the magnitude and impact of the problem of infection among patients treated with hemodialysis (HD) and peritoneal dialysis (PD) using data from national registries and large cohort studies of patients with end-stage renal disease (ESRD). United States Renal Data System (USRDS) data indicate that in the United States for years 1991 to 1992, infection accounted for 12% of all deaths among HD patients and 15% of all deaths among PD patients. Septicemia was the underlying cause in 76% of these infectious deaths among HD patients, of which the vascular access, peritonitis, peripheral vascular disease, and other causes accounted for 12%, 5%, 24%, and 59% respectively. Among PD patients, septicemia accounted for 79% of infectious deaths. Of these deaths attributable to septicemia, peritonitis, peripheral vascular disease, and other causes were reported as the cause in 35%, 23%, and 41% respectively. Infection is also a major cause of morbidity in the dialysis population. Among HD patients, an average of 7.6 bacteremic episodes per 100 patient years (0.076 per year) has been described, of which 48% were associated with access infections. Among PD patients, studies have reported peritonitis rates ranging from 1 in 7.6 to 21.5 months (0.56 to 1.58 per patient year) and exit and/or tunnel infections occurring at a rate of 0.6 episodes per year. The known predictors of infectious complications among these populations are reviewed.

The 2006 William Feinberg lecture: shifting the paradigm from stroke to global vascular risk estimation.

PubMed

Sacco, Ralph L

2007-06-01

By the year 2010, it is estimated that 18.1 million people worldwide will die annually because of cardiovascular diseases and stroke. "Global vascular risk" more broadly includes the multiple overlapping disease silos of stroke, myocardial infarction, peripheral arterial disease, and vascular death. Estimation of global vascular risk requires consideration of a variety of variables including demographics, environmental behaviors, and risk factors. Data from multiple studies suggest continuous linear relationships between the physiological vascular risk modulators of blood pressure, lipids, and blood glucose rather than treating these conditions as categorical risk factors. Constellations of risk factors may be more relevant than individual categorical components. Exciting work with novel risk factors may also have predictive value in estimates of global vascular risk. Advances in imaging have led to the measurement of subclinical conditions such as carotid intima-media thickness and subclinical brain conditions such as white matter hyperintensities and silent infarcts. These subclinical measurements may be intermediate stages in the transition from asymptomatic to symptomatic vascular events, appear to be associated with the fundamental vascular risk factors, and represent opportunities to more precisely quantitate disease progression. The expansion of studies in molecular epidemiology and detection of genetic markers underlying vascular risks also promises to extend our precision of global vascular risk estimation. Global vascular risk estimation will require quantitative methods that bundle these multi-dimensional data into more precise estimates of future risk. The power of genetic information coupled with data on demographics, risk-inducing behaviors, vascular risk modulators, biomarkers, and measures of subclinical conditions should provide the most realistic approximation of an individual's future global vascular risk. The ultimate public health benefit, however, will depend on not only identification of global vascular risk but also the realization that we can modify this risk and prove the prediction models wrong.

Predictors of Clinical Outcome after Reconstruction of Complex Soft Tissue Defects Involving the Achilles Tendon with the Composite Anterolateral Thigh Flap with Vascularized Fascia Lata.

PubMed

Jandali, Zaher; Lam, Martin C; Merwart, Benedikt; Möhring, Bernd; Geil, Stephanie; Müller, Klaus; Ionac, Mihai; Jiga, Lucian P

2018-06-26

 The composite anterolateral thigh flap with vascularized fascia lata (ALT-FL flap) for covering complex soft tissue defects involving the Achilles tendon has shown promising results. The age and body mass index (BMI) are important predictors of clinical outcome after surgical treatment of Achilles tendon ruptures. In this study, we investigate whether these also influence the outcome of patients after Achilles tendon reconstruction using the ALT-FL flap.  Twenty patients (mean age: 55.9 ± 8.7 years) with complex tissue defects involving the Achilles tendon underwent reconstruction with the ALT-FL flap. Both the Achilles tendon Total Rupture Score (ATRS) and the American Orthopaedic Foot and Ankle Society (AOFAS) score were assessed preoperatively and 12 months postoperatively. In addition, postoperative magnetic resonance imaging (MRI) studies and measurements of the ankle range of motion were performed and results compared with existing literature.  All flaps survived and MRI studies confirmed complete anatomical integration of the fascia lata as "neotendon" at the recipient site. In our patient cohort, the age did not correlate with the outcome measurements, whereas the BMI showed significant negative correlation with the postoperative ATRS ( p  < 0.001) and AOFAS scores ( p  < 0.05). The ATRS and AOFAS scores of all patients improved significantly ( p  < 0.001). However, obese patients with a BMI of more than 30 kg/m 2 achieved significant lower ATRS ( p  < 0.001) and AOFAS scores ( p  < 0.01), as well as patients with peripheral artery disease (PAD) ( p  < 0.05). The mean ankle range of motion after ALT-FL flap reconstruction remained statistical insignificant compared with previous avascular or vascularized tendon repairs of the Achilles tendon.  The ALT-FL flap enables reconstruction of complex tissue defects involving the Achilles tendon with good functional results. However, the presence of an increased BMI or PAD, but not necessarily the age, proves to be a predictor of poor clinical outcome and therefore should be subject to scrutiny during patient selection. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

[Multicentric hyaline vascular Castleman's disease. A POEMS type variant].

PubMed

Gracia-Ramos, Abraham Edgar; Cruz-Domínguez, María del Pilar; Vera-Lastra, Olga Lidia

2013-01-01

Castleman's disease is an atypical lymphoproliferative disorder which may be compatible with paraneoplastic manifestations of POEMS syndrome. a 53 year old man with a history of type 2 diabetes, hypothyroidism and Addison's disease presented with numbness and weakness in limbs, dyspnea, skin hardening, Raynaud's phenomenon, weight loss and fatigue. A physical exam showed tachypnea, generalized cutaneous hyperpigmentation and skin hardening of extremities, muscle weakness, hypoesthesia and hyporeflexia. Laboratory showed hyperprolactinemia, low testosterone, hypothyroidism and Addison's disease. Electrophoresis of proteins showed polyclonal hypergammaglobulinemia. Somatosensory evoked potentials reported peripheral neuropathy and severe axonal polyneuropathy by electromyography. Chest X-rays showed bilateral reticular infiltrates and mediastinal widening. An echocardiogram displayed moderate pulmonary hypertension. Skin biopsy had no evidence of scleroderma. CT reported axillar, mediastinal and retroperitoneal nodes. The mediastinal lesion biopsy reported hyaline vascular Castleman's disease, multicentric variety. He was treated with rituximab. the case meet criteria for multicentric hyaline vascular Castleman's disease, POEMS variant, treated with rituximab.

Pathophysiology of hypertension: interactions between macro and microvascular alterations through endothelial dysfunction.

PubMed

Yannoutsos, Alexandra; Levy, Bernard I; Safar, Michel E; Slama, Gerard; Blacher, Jacques

2014-02-01

Hypertension is a multifactorial systemic chronic disorder through functional and structural macrovascular and microvascular alterations. Macrovascular alterations are featured by arterial stiffening, disturbed wave reflection and altered central to peripheral pulse pressure amplification. Microvascular alterations, including altered wall-to-lumen ratio of larger arterioles, vasomotor tone abnormalities and network rarefaction, lead to disturbed tissue perfusion and susceptibility to ischemia. Central arterial stiffness and microvascular alterations are common denominators of organ damages. Vascular alterations are intercorrelated, amplifying the haemodynamic load and causing further damage in the arterial network. A plausible precursor role of vascular alterations in incident hypertension provides new insights for preventive and therapeutic strategies targeting macro and microvasculature. Cumulative metabolic burden and oxidative stress lead to chronic endothelial injury, promoting structural and functional vascular alterations, especially in the microvascular network. Pathophysiology of hypertension may then be revisited, based on both macrovascular and microvascular alterations, with a precursor role of endothelial dysfunction for the latter.

Microparticles Engineered to Highly Express Peroxisome Proliferator-Activated Receptor-γ Decreased Inflammatory Mediator Production and Increased Adhesion of Recipient Monocytes

PubMed Central

Sahler, Julie; Woeller, Collynn F.; Phipps, Richard P.

2014-01-01

Circulating blood microparticles are submicron vesicles released primarily by megakaryocytes and platelets that act as transcellular communicators. Inflammatory conditions exhibit elevated blood microparticle numbers compared to healthy conditions. Direct functional consequences of microparticle composition, especially internal composition, on recipient cells are poorly understood. Our objective was to evaluate if microparticle composition could impact the function of recipient cells, particularly during inflammatory provocation. We therefore engineered the composition of megakaryocyte culture-derived microparticles to generate distinct microparticle populations that were given to human monocytes to assay for influences recipient cell function. Herein, we tested the responses of monocytes exposed to either control microparticles or microparticles that contain the anti-inflammatory transcription factor, peroxisome proliferator-activated receptor-γ (PPARγ). In order to normalize relative microparticle abundance from two microparticle populations, we implemented a novel approach that utilizes a Nanodrop Spectrophotometer to assay for microparticle density rather than concentration. We found that when given to peripheral blood mononuclear cells, microparticles were preferentially internalized by CD11b+ cells, and furthermore, microparticle composition had a profound functional impact on recipient monocytes. Specifically, microparticles containing PPARγ reduced activated monocyte production of the proinflammatory cytokines interleukin-8 and monocyte chemotactic protein-1 compared to activated monocytes exposed to control microparticles. Additionally, treatment with PPARγ microparticles greatly increased monocyte cell adherence. This change in morphology occurred simultaneously with increased production of the key extracellular matrix protein, fibronectin and increased expression of the fibronectin-binding integrin, ITGA5. PPARγ microparticles also changed monocyte mRNA levels of several genes including those under PPARγ control. Overall, the delivery of PPARγ from microparticles to human monocytes influenced gene expression, decreased inflammatory mediator production and increased monocyte adherence. These results support the concept that the composition of blood microparticles has a profound impact on the function of cells with which they interact, and likely plays a role in vascular inflammation. PMID:25426628

Microparticles engineered to highly express peroxisome proliferator-activated receptor-γ decreased inflammatory mediator production and increased adhesion of recipient monocytes.

PubMed

Sahler, Julie; Woeller, Collynn F; Phipps, Richard P

2014-01-01

Circulating blood microparticles are submicron vesicles released primarily by megakaryocytes and platelets that act as transcellular communicators. Inflammatory conditions exhibit elevated blood microparticle numbers compared to healthy conditions. Direct functional consequences of microparticle composition, especially internal composition, on recipient cells are poorly understood. Our objective was to evaluate if microparticle composition could impact the function of recipient cells, particularly during inflammatory provocation. We therefore engineered the composition of megakaryocyte culture-derived microparticles to generate distinct microparticle populations that were given to human monocytes to assay for influences recipient cell function. Herein, we tested the responses of monocytes exposed to either control microparticles or microparticles that contain the anti-inflammatory transcription factor, peroxisome proliferator-activated receptor-γ (PPARγ). In order to normalize relative microparticle abundance from two microparticle populations, we implemented a novel approach that utilizes a Nanodrop Spectrophotometer to assay for microparticle density rather than concentration. We found that when given to peripheral blood mononuclear cells, microparticles were preferentially internalized by CD11b+ cells, and furthermore, microparticle composition had a profound functional impact on recipient monocytes. Specifically, microparticles containing PPARγ reduced activated monocyte production of the proinflammatory cytokines interleukin-8 and monocyte chemotactic protein-1 compared to activated monocytes exposed to control microparticles. Additionally, treatment with PPARγ microparticles greatly increased monocyte cell adherence. This change in morphology occurred simultaneously with increased production of the key extracellular matrix protein, fibronectin and increased expression of the fibronectin-binding integrin, ITGA5. PPARγ microparticles also changed monocyte mRNA levels of several genes including those under PPARγ control. Overall, the delivery of PPARγ from microparticles to human monocytes influenced gene expression, decreased inflammatory mediator production and increased monocyte adherence. These results support the concept that the composition of blood microparticles has a profound impact on the function of cells with which they interact, and likely plays a role in vascular inflammation.

A free vascularized tibia-fibular composite graft for the traumatic femoral bony defect of a 6-year-old boy with 10-year follow up: a case report

PubMed Central

2013-01-01

Introduction Free vascularized fibular grafts have been widely used for the reconstruction of long bone defects. However, the use of a vascularized tibial graft is precluded by its weight-bearing function and unacceptable donor site morbidity. Case presentation We present a rare case of using a vascularized tibia-fibular composite graft taken from a 6-year-old Chinese boy’s ipsilateral lower leg to reconstruct a large bony defect of his traumatic femur. Hypertrophy of the tibial graft, good remodeling of the femoral shaft, and atrophy of the unloaded fibular graft were noted at the 10-year follow up. He was able to participate in outdoor activities such as basketball while wearing his prosthesis. Conclusions The 10-year follow up demonstrates the feasibility of this salvage procedure for a floating knee injury with neurovascular compromise. PMID:23714102

Retinal microvascular changes and subsequent vascular events after ischemic stroke.

PubMed

De Silva, D A; Manzano, J J F; Liu, E Y; Woon, F-P; Wong, W-X; Chang, H-M; Chen, C; Lindley, R I; Wang, J J; Mitchell, P; Wong, T-Y; Wong, M-C

2011-08-30

Retinal microvasculature changes are associated with vascular events including stroke in healthy populations. It is not known whether retinal microvascular changes predict recurrent vascular events after ischemic stroke. We examined the relationship between retinal microvascular signs and subsequent vascular events in a prospective cohort of 652 acute ischemic stroke patients admitted to a tertiary hospital in Singapore from 2005 to 2007. Retinal photographs taken within 1 week of stroke onset were assessed in a masked manner for quantitative and qualitative measures. Follow-up data over 2-4 years were obtained by standardized telephone interview and then were verified from medical records. Predictors of recurrent vascular events (cerebrovascular, coronary, vascular death, and composite vascular events) were determined using Cox regression models. Follow-up data over a median of 29 months were obtained for 89% (652 patients) of the cohort. After adjustment for covariates including traditional risk factors and index stroke etiology, patients with severe arteriovenous nicking (AVN) were more likely to have a recurrent cerebrovascular event (hazard ratio [HR] 2.28, 95% confidence interval [CI] 1.20-4.33) compared with those without AVN. Patients with severe focal arteriolar narrowing (FAN) were more likely to have a recurrent cerebrovascular event (HR 2.75, 95% CI 1.14-6.63) or subsequent composite vascular event (HR 2.77, 95% CI 1.31-5.86) compared to those without FAN. Retinal microvascular changes predicted subsequent vascular events after ischemic stroke, independent of traditional risk factors and stroke subtype. Thus, retinal imaging has a potential role in predicting the risk of recurrent vascular events after ischemic stroke and in understanding novel vascular risk factors.

A PC-PU nanoparticle/PU/decellularized scaffold composite vascular patch: Synergistically optimized overall performance promotes endothelialization.

PubMed

Zhang, Jun; Liu, Cheng; Feng, Fuling; Wang, Dawei; Lu, Shuaishuai; Wei, Guo; Mo, Hong; Qiao, Tong

2017-12-01

Composite vascular patches have gained increasingly attention due to the limited availability of autologous patches (vascular graft materials made from the blood vessels of the same recipient), the lack of growth capability of nonautologous patches (vascular graft materials made from the blood vessels of a different donor) and the disadvantages of synthetic patches. In this study, we report a highly biocompatible phosphatidylcholine-polyurethane nanoparticle/polyurethane/decellularized scaffold composite vascular patch (PCVP). It was fabricated by a facile method - cosedimentation. Its in vitro blood and cell compatibility including hemolysis, plasma recalcification time, coagulation time, platelet adhesion and cytotoxicity was evaluated. The surface modified with phosphatidylcholine-polyurethane (PC-PU) nanoparticles exhibited the improved anticoagulation activity. The in vivo performance of the PCVP was investigated in a mouse model. The nanopatterned surface that resembled the concave-convex structure of the luminal surface of native blood vessels enhanced cell attachment, proliferation, migration and differentiation. The decellularized scaffold had the mechanical property similar to that of the targeted blood vessels, which could withstand in vivo dynamic blood pressure. The overall performance of the PCVP was synergistically optimized by each layer of the multilayer design. The patched artery remained patent and the formation of endothelial tissue - endothelialization was achieved 30days after the in vivo implantation in a mouse model. Copyright © 2017 Elsevier B.V. All rights reserved.

Incidence and severity of phlebitis in patients receiving peripherally infused amiodarone.

PubMed

Boyce, Brenda A Brady; Yee, Barbara Homer

2012-08-01

Nurses noted that the rate of phlebitis was high when intravenous amiodarone was infused via a peripheral site. Hospital policy recommends a central vascular catheter, but this method is often not feasible because the drug is administered in emergent situations for short periods. To determine the rate and severity of phlebitis in patients given peripherally infused amiodarone. The literature, policy, and procedures for administration of amiodarone were reviewed; the pharmacy was consulted; and a data collection tool was developed. The tool was pilot tested and revised, and face validation was established. Data were collected during a 6-month period. A convenience sample was used. The study included a total of 12 patients. Each new infusion of intravenous amiodarone was considered a separate occurrence, for a total of 24 infusions. Various grades of phlebitis developed in 8 patients (67%). Phlebitis developed at 12 of the 24 infusion sites (50%). Patients receiving peripherally infused amiodarone are at high risk for phlebitis. This complication may lead to infection, additional medical intervention, delay in treatment, and prolonged hospitalization.

[Vasculitic Peripheral Neuropathies: Clinical Features and Diagnostic Laboratory Tests].

PubMed

Ogata, Katsuhisa

2016-03-01

Vasculitic peripheral neuropathy (VPN) occurs due to ischemic changes of peripheral nerves, resulting from a deficit of vascular blood supply due to damaged vasa nervorum leading to vasculitis. VPN usually manifests as sensorimotor or sensory disturbances accompanied by pain, presenting as a type of multiple mononeuropathy, with a scattered distribution in distal limbs. VPN may also present as a mononeuropathy, distal symmetric polyneuropathy, plexopathy, or radiculopathy. The rapidity of VPN is variable, ranging from days to months, with symptoms occasionally changing with the appearance of new lesions. Careful history taking and neurological examination provides an exact diagnosis. The most common cause of VPN is primary vasculitis predominantly affecting small vessels, including vasa nervorum, anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, and polyarteritis nodosa. Similar vasculitic processes can also result from a systemic collagen disorder or secondary vasculitis. Electrophysiological studies and pathological investigation of biopsied peripheral nerves and muscles are important for diagnosis of vasculitis. Serological tests, including ANCA, are useful for diagnosis of vasculitis. Accurate neurological examinations are essential for diagnosis and evaluation of clinical course.

[Histocompatibility of nano-hydroxyapatite/poly-co-glycolic acid tissue engineering bone modified by mesenchymal stem cells with vascular endothelial frowth factor].

PubMed

Zhang, Minglei; Wang, Dapeng; Yin, Ruofeng

2015-10-06

To explorec Histocompatibility of nano-hydroxyapatite/poly-co-glycolic acid tissue engineering bone modified by mesenchymal stem cells with vascular endothelial frowth factor transinfected. Rat bone marrow mesenchymal stem cells (BMSCs) was separated, using BMSCs as target cells, and then vascular endothelial growth factor (VEGF) gene was transfected. Composite bone marrow mesenchymal stem cells and cells transfected with nano-hydroxyapatite (HA)/polylactic-co-glycolic acid (PLGA). The composition of cell and scaffold was observed. The blank plasmid transfection was 39.1%, 40.1% in VEGF group. The cell adhesion and growth was found on the scaffold pore wall after 5 days, and the number of adherent cells in the nano-HA/PLGA composite scaffold material basically had no significant difference in both. Although the nano-HA/PLGA scaffold material is still not fully meet the requirements of the matrix material for bone tissue engineering, but good biocompatibility, structure is its rich microporous satisfaction in material mechanics, toughening, enhanced obviously. Composition scaffold with BMSCs transfected by VEGF plasmid, the ability of angiogenesis is promoted.

P14.21 Can vascular risk factors influence number of brain metastases?

PubMed Central

Berk, B.; Nagel, S.; Kortmann, R.; Hoffmann, K.; Gaudino, C.; Seidel, C.

2017-01-01

Abstract BACKGROUND: Up to 30-40% of patients with solid tumors develop cerebral metastases. Number of cerebral metastases is relevant for treatment and prognosis. However, factors that determine number of metastases are not well defined. Distribution of metastases is influenced by blood vessels and cerebral small vessel disease can reduce number of metastases. Aim of this pilot study was to analyze the influence of vascular risk factors (arterial hypertension, diabetes mellitus, smoking, hypercholesterolemia) and of peripheral arterial occlusive disease (PAOD) on number of brain metastases. METHODS: 200 patients with pre-therapeutic 3D-brain MRI and available clinical data were analyzed retrospectively. Number of metastases (NoM) was compared between patients with/without vascular risk factors (vasRF). Results: Patients with PAOD had significant less brain metastases than patients without PAOD (NoM=4.43 vs. 6.02, p=0.043), no other single vasRF conferred a significant effect on NoM. NoM differed significantly between different tumor entities. CONCLUSION: Presence of PAOD showed some effect on number of brain metastases implying that tumor-independent vascular factors can influence brain metastasation.

IR imaging of blood circulation of patients with vascular disease

NASA Astrophysics Data System (ADS)

Wang, Hsin; Wade, Dwight R., Jr.; Kam, Jack

2004-04-01

We conducted a preliminary IR imaging study of blood circulation in patients with peripheral vascular diseases. Abnormal blood flow is common in older adults, especially those with elevated blood lipids, diabetes, hypertension, and a history of smoking. All of these conditions have a high prevalence in our population, often with more than one condition in the same individual. The differences in blood flow is revealed by temperature differences in areas of the extremities as well as other regions of the body. However, what is needed is an imaging technique that is relatively inexpensive and can reveal the blood flow in real time. The IR imaging can show detailed venous system and small tempearture changes associated with blood flow. Six patients with vascular diseases were tested in a clinic set up. Their legs and feet were imaged. We observed large temperature differences (cooling of more than 10° C) at the foot, especially toes. More valuable information were obtained from the temperature distribution maps. IR thermography is potentially a very valuable tool for medical application, especially for vascular diseases.

Strategies for the Segmentation of Subcutaneous Vascular Patterns in Thermographic Images

NASA Astrophysics Data System (ADS)

Chan, Eric K. Y.; Pearce, John A.

1989-05-01

Computer-assisted segmentation of vascular patterns in thermographic images provides the clinician with graphic outlines of thermally significant subcutaneous blood vessels. Segmentation strategies compared here consist of image smoothing protocols followed by thresholding and zero-crossing edge detectors. Median prefiltering followed by the Frei-Chen algorithm gave the most reproducible results, with an execution time of 143 seconds for 256 X 256 images. The Laplacian of Gaussian operator was not suitable due to streak artifacts in the thermographic imaging system. This computerized process may be adopted in a fast paced clinical environment to aid in the diagnosis and assessment of peripheral circulatory diseases, Raynaud's Disease3, phlebitis, varicose veins, as well as diseases of the autonomic nervous system. The same methodology may be applied to enhance the appearance of abnormal breast vascular patterns, and hence serve as an adjunct to mammography in the diagnosis of breast cancer. The automatically segmented vascular patterns, which have a hand drawn appearance, may also be used as a data reduction precursor to higher level pattern analysis and classification tasks.

Clarification of serotonin-induced effects in peripheral artery disease observed through the femoral artery response in models of diabetes and vascular occlusion: The role of calcium ions.

PubMed

Stojanović, Marko; Prostran, Milica; Janković, Radmila; Radenković, Miroslav

2017-07-01

Recent findings have demonstrated that serotonin is an important participant in the development and progression of peripheral artery diseases. Taking this into consideration, the goals of this study were to investigate the effects of serotonin on isolated Wistar rat femoral arteries in both healthy and diabetic animals, with and without artery occlusion, with a particular focus on determining the role of calcium in this process. Contraction experiments with serotonin on intact and denuded femoral artery rings, in the presence or absence of nifedipine and ouabain (both separately, or in combination), as well as Ca 2+ -free Krebs-Ringer bicarbonate solution were performed. The serotonin-induced results were concentration dependent, but only in healthy animals. The endothelium-dependent contraction of the femoral artery was assessed. In healthy animals, the endothelium-reliant part of contraction was dependent on the extracellular calcium, while the smooth muscle-related part was instead dependent on the intracellular calcium. In diabetic animals, both nifedipine and ouabain influenced serotonin-induced vascular effects by blocking intracellular calcium pathways. However, this was diminished after the simultaneous administration of both blockers. © 2017 John Wiley & Sons Australia, Ltd.

Akt1 Controls the Timing and Amplitude of Vascular Circadian Gene Expression

PubMed Central

Luciano, Amelia K.; Santana, Jeans M.; Velazquez, Heino; Sessa, William C.

2017-01-01

The AKT signaling pathway is important for circadian rhythms in mammals and flies (Drosophila). However, AKT signaling in mammals is more complicated since there are 3 isoforms of AKT, each performing slightly different functions. Here we study the most ubiquitous AKT isoform, Akt1, and its role at the organismal level in the central and vascular peripheral clocks. Akt1−/− mice exhibit relatively normal behavioral rhythms with only minor differences in circadian gene expression in the liver and heart. However, circadian gene expression in the Akt1−/− aorta, compared with control aorta, follows a distinct pattern. In the Akt1−/− aorta, positive regulators of circadian transcription have lower amplitude rhythms and peak earlier in the day, and negative circadian regulators are expressed at higher amplitudes and peak later in the day. In endothelial cells, negative circadian regulators exhibit an increased amplitude of expression, while the positive circadian regulators are arrhythmic with a decreased amplitude of expression. This indicates that Akt1 conditions the normal circadian rhythm in the vasculature more so than in other peripheral tissues where other AKT isoforms or kinases might be important for daily rhythms. PMID:28452287

Biomechanics and functional morphology of a climbing monocot

PubMed Central

Hesse, Linnea; Wagner, Sarah T.; Neinhuis, Christoph

2016-01-01

Plants with a climbing growth habit possess unique biomechanical properties arising from adaptations to changing loading conditions connected with close attachment to mechanical supports. In monocot climbers, mechanical adaptation is restricted by the absence of a bifacial vascular cambium. Flagellaria indica was used to investigate the mechanical properties and adaptations of a monocot climber that, uniquely, attaches to the surrounding vegetation via leaf tendrils. Biomechanical methods such as three-point bending and torsion tests were used together with anatomical studies on tissue development, modification and distribution. In general, the torsional modulus was lower than the bending modulus; hence, torsional stiffness was less than flexural stiffness. Basal parts of mature stems showed the greatest stiffness while that of more apical stem segments levelled off. Mechanical properties were modulated via tissue maturation processes mainly affecting the peripheral region of the stem. Peripheral vascular bundles showed a reduction in the amount of conducting tissue while the proportion and density of the bundle sheath increased. Furthermore, adjacent bundle sheaths merged resulting in a dense ring of fibrous tissue. Although F. indica lacks secondary cambial growth, the climbing habit is facilitated by a complex interaction of tissue maturation and attachment. PMID:26819259

Analysis of Tumor Vessel Supply in Lewis Lung Carcinoma in Mice by Fluorescent Microsphere Distribution and Imaging with Micro- and Flat-Panel Computed Tomography

PubMed Central

Savai, Rajkumar; Wolf, Joachim C.; Greschus, Susanne; Eul, Bastian G.; Schermuly, Ralph T.; Hänze, Jörg; Voswinckel, Robert; Langheinrich, Alexander C.; Grimminger, Friedrich; Traupe, Horst; Seeger, Werner; Rose, Frank

2005-01-01

In lung carcinomas the blood supply varies depending on tumor type and stage and can develop from pulmonary or bronchial circulation, or both. To examine this in vivo, primary bronchogenic Lewis lung carcinoma cells were intratracheally instilled in C57BL/6 mice. Within 7 days, histological examinations showed progressive tumor growth at the peripheral parenchymal region. The relative contribution of tumor blood supply via the pulmonary and systemic arteries was studied in detail using fluorescent microspheres (10 μm). When compared to healthy lung parenchyma (13:1), Lewis lung carcinoma tumor tissue (52:1) showed a fourfold increase in pulmonary to systemic microspheres, indicating that the pulmonary arteries are the predominant tumor-feeding vessels. After filling the vessels with a vascular cast, the microanatomy of vessels being derived from the pulmonary artery was visualized with micro computed tomography. Flat-panel volumetric computed tomography provided longitudinal visualization of tissue bridges between the growing tumor and the pulmonary vasculature. In this model of peripheral parenchymal malignancy, new imaging techniques allowed effective visualization of lung tumor growth and vascularization in living mice, demonstrating a pulmonary blood supply for lung tumors. PMID:16192630

New modalities of ultrasound-based intima-media thickness, arterial stiffness and non-coronary vascular calcifications detection to assess cardiovascular risk.

PubMed

Flore, R; Ponziani, F R; Tinelli, G; Arena, V; Fonnesu, C; Nesci, A; Santoro, L; Tondi, P; Santoliquido, A

2015-04-01

Carotid intima-media thickness (c-IMT), arterial stiffness (AS) and vascular calcification (VC) are now considered important new markers of atherosclerosis and have been associated with increased prevalence of cardiovascular events. An accurate, reproducible and easy detection of these parameters could increase the prognostic value of the traditional cardiovascular risk factors in many subjects at low and intermediate risk. Today, c-IMT and AS can be measured by ultrasound, while cardiac computed tomography is the gold standard to quantify coronary VC, although concern about the reproducibility of the former and the safety of the latter have been raised. Nevertheless, a safe and reliable method to quantify non-coronary (i.e., peripheral) VC has not been detected yet. To review the most innovative and accurate ultrasound-based modalities of c-IMT and AS detection and to describe a novel UltraSound-Based Carotid, Aortic and Lower limbs Calcification Score (USB-CALCs, simply named CALC), allowing to quantify peripheral calcifications. Finally, to propose a system for cardiovascular risk reclassification derived from the global evaluation of "Quality Intima-Media Thickness", "Quality Arterial Stiffness", and "CALC score" in addition to the Framingham score.

Akt1 Controls the Timing and Amplitude of Vascular Circadian Gene Expression.

PubMed

Luciano, Amelia K; Santana, Jeans M; Velazquez, Heino; Sessa, William C

2017-06-01

The AKT signaling pathway is important for circadian rhythms in mammals and flies ( Drosophila). However, AKT signaling in mammals is more complicated since there are 3 isoforms of AKT, each performing slightly different functions. Here we study the most ubiquitous AKT isoform, Akt1, and its role at the organismal level in the central and vascular peripheral clocks. Akt1 -/- mice exhibit relatively normal behavioral rhythms with only minor differences in circadian gene expression in the liver and heart. However, circadian gene expression in the Akt1 -/- aorta, compared with control aorta, follows a distinct pattern. In the Akt1 -/- aorta, positive regulators of circadian transcription have lower amplitude rhythms and peak earlier in the day, and negative circadian regulators are expressed at higher amplitudes and peak later in the day. In endothelial cells, negative circadian regulators exhibit an increased amplitude of expression, while the positive circadian regulators are arrhythmic with a decreased amplitude of expression. This indicates that Akt1 conditions the normal circadian rhythm in the vasculature more so than in other peripheral tissues where other AKT isoforms or kinases might be important for daily rhythms.

Circadian Rhythms in Diet-Induced Obesity.

PubMed

Engin, Atilla

2017-01-01

The biological clocks of the circadian timing system coordinate cellular and physiological processes and synchronizes these with daily cycles, feeding patterns also regulates circadian clocks. The clock genes and adipocytokines show circadian rhythmicity. Dysfunction of these genes are involved in the alteration of these adipokines during the development of obesity. Food availability promotes the stimuli associated with food intake which is a circadian oscillator outside of the suprachiasmatic nucleus (SCN). Its circadian rhythm is arranged with the predictable daily mealtimes. Food anticipatory activity is mediated by a self-sustained circadian timing and its principal component is food entrained oscillator. However, the hypothalamus has a crucial role in the regulation of energy balance rather than food intake. Fatty acids or their metabolites can modulate neuronal activity by brain nutrient-sensing neurons involved in the regulation of energy and glucose homeostasis. The timing of three-meal schedules indicates close association with the plasma levels of insulin and preceding food availability. Desynchronization between the central and peripheral clocks by altered timing of food intake and diet composition can lead to uncoupling of peripheral clocks from the central pacemaker and to the development of metabolic disorders. Metabolic dysfunction is associated with circadian disturbances at both central and peripheral levels and, eventual disruption of circadian clock functioning can lead to obesity. While CLOCK expression levels are increased with high fat diet-induced obesity, peroxisome proliferator-activated receptor (PPAR) alpha increases the transcriptional level of brain and muscle ARNT-like 1 (BMAL1) in obese subjects. Consequently, disruption of clock genes results in dyslipidemia, insulin resistance and obesity. Modifying the time of feeding alone can greatly affect body weight. Changes in the circadian clock are associated with temporal alterations in feeding behavior and increased weight gain. Thus, shift work is associated with increased risk for obesity, diabetes and cardio-vascular diseases as a result of unusual eating time and disruption of circadian rhythm.

Emerging Roles of GPER in Diabetes and Atherosclerosis

PubMed Central

Barton, Matthias; Prossnitz, Eric R.

2015-01-01

G protein-coupled estrogen receptor (GPER) is a 7-transmembrane receptor implicated in rapid estrogen signaling. Originally cloned from vascular endothelial cells, GPER plays a central role in the regulation of vascular tone and cell growth, as well as lipid and glucose homeostasis. This review highlights our knowledge of the physiological and pathophysiological functions of GPER in the pancreas, peripheral and immune tissues, and the arterial vasculature. Recent findings of its roles in obesity, diabetes, and atherosclerosis, including the GPER-dependent regulation of lipid metabolism and inflammation, are presented. The therapeutic potential of targeting GPER-dependent pathways in chronic diseases such as coronary artery disease and diabetes and in the context of menopause is also discussed. PMID:25767029

Patent foramen ovale transcatheter closure vs. medical therapy on recurrent vascular events: a systematic review and meta-analysis of randomized controlled trials.

PubMed

Rengifo-Moreno, Pablo; Palacios, Igor F; Junpaparp, Parichart; Witzke, Christian F; Morris, D Lynn; Romero-Corral, Abel

2013-11-01

In patients with cryptogenic stroke, transcatheter (TC) closure of a patent foramen ovale (PFO) has not been shown to better prevent recurrent vascular events than medical therapy. However, randomized controlled trials (RCT) to date have included few vascular events, and lack of power has been raised as an important concern. To conduct a systematic review and meta-analysis of existing RCT published studies assessing the recurrence of vascular events after TC PFO closure when compared to medical therapy. Using the search terms "patent foramen ovale", "PFO", "stroke", "percutaneous closure" and "transcatheter closure", Medline, Pubmed, Embase, and Cochrane databases were reviewed from inception through April 2013, with no language restrictions. Only studies in adult humans were considered. Additional references were obtained from the bibliographies of studies reviewed. The following criteria were used for study selection: 1) randomized controlled trial, 2) subjects were adult patients with cryptogenic stroke who were randomized to TC PFO closure or medical treatment (antiplatelet therapy and/or anticoagulation), and 3) reported outcomes included cardiac death, all death, stroke, transient ischemic attack, and peripheral embolism. Methodological and descriptive data, adverse events (including raw data and risk estimates), as well as procedural success and complications were abstracted in duplicate from each study independently, and agreement was tested. We followed rigorously the recommended guidelines for reporting and conducting and assessing quality of meta-analysis of RCT. The primary endpoints pre-specified in advance were recurrent vascular events, and composite endpoint of death, and recurrent vascular events. Three studies were identified as meeting selection criteria. These included a total of 2,303 patients, with 1,150 patients randomized to TC PFO closure and 1,153 patients randomized to medical therapy. Mean follow-up was 3.5 years. Baseline characteristics (age, sex, and cardiovascular risk factors) were similar across studies. Intention-to-treat analyses showed a statistically significant risk reduction in stroke and/or transient ischemic attack in the TC PFO closure group when compared to medical treatment, pooled HR = 0.59, 95%CI (0.36-0.97), P = 0.04. The combined outcome of death, and vascular events, showed a borderline statistically significant benefit for TC PFO closure when compared to medical treatment, pooled HR = 0.67, 95%CI (0.44-1.00), P = 0.05 Subjects with a substantial PFO shunt seem to benefit the most with TC PFO closure, pooled HR = 0.35, 95%CI (0.12-1.03), P = 0.06, however, it did not reach statistical significance. These results suggest that in patients with cryptogenic stroke, TC PFO closure may be beneficial in reducing the risk of recurrent vascular events when compared to medical treatment. The benefit of TC PFO closure may be greater in patients with a substantial shunt.

HEMATOPOIETIC STEM CELL INFUSION/TRANSPLANTATION FOR INDUCTION OF ALLOGRAFT TOLERANCE

PubMed Central

Granados, Jose M. Marino; Benichou, Gilles; Kawai, Tatsuo

2015-01-01

Purpose of review This review updates the current status of basic, preclinical, and clinical research on donor hematopoietic stem cell infusion for allograft tolerance induction. Recent findings Recent basic studies in mice provide evidence of significant involvement of both central deletional and peripheral regulatory mechanisms in induction and maintenance of allograft tolerance effected through a mixed chimerism approach with donor hematopoietic stem cell infusion. The presence of heterologous memory T cells in primates hampers the induction of persistent chimerism. Durable mixed chimerism, however, now has been recently induced in inbred major histocompatibility complex-mismatched swine, resulting in tolerance of vascularized composite tissue allografts. In clinical transplantation, allograft tolerance has been achieved in human leukocyte antigen-mismatched kidney transplantation after the induction of transient mixed chimerism or persistent full donor chimerism. Summary Tolerance induction in clinical kidney transplantation has been achieved by donor hematopoietic stem cell infusion. Improving the consistency and safety of tolerance induction and extending successful protocols to other organs, as well as to organs from deceased donors, are critical next steps to bringing tolerance to a wider range of clinical applications. PMID:25563992

Handling of peripheral intravenous cannulae: effects of evidence-based clinical guidelines.

PubMed

Ahlqvist, Margary; Bogren, Agneta; Hagman, Sari; Nazar, Isabel; Nilsson, Katarina; Nordin, Karin; Valfridsson, Berit Sunde; Söderlund, Mona; Nordström, Gun

2006-11-01

This study aimed at evaluating the outcome of implemented evidence-based clinical guidelines by means of surveying the frequency of thrombophlebitis, nurses' care, handling and documentation of peripheral intravenous cannulae. Peripheral intravenous cannulae are frequently used for vascular access and, thereby, the patients will be exposed to local and systemic infectious complications. Evidence-based knowledge of how to prevent these complications and how to care for patients with peripheral intravenous cannula is therefore of great importance. Deficient care, handling and documentation of peripheral intravenous cannulae have previously been reported. A cross-sectional survey was conducted by a group of nurses at three wards at a university hospital before and after the implementation of the evidence-based guidelines. A structured observation protocol was used to review the frequency of thrombophlebitis, the nurses' care, handling and the documentation of peripheral intravenous cannulae in the patient's record. A total of 107 and 99 cannulae respectively were observed before and after the implementation of the guidelines. The frequency of peripheral intravenous cannulae without signs of thrombophlebitis increased by 21% (P < 0.01) and the use of cannula size 0.8 mm increased by 22% (P < 0.001). Nurses' documentation of peripheral intravenous cannula improved significantly (P < 0.001). We conclude that implementation of the guidelines resulted in significant improvements by means of decreased frequency of signs of thrombophlebitis, increased application of smaller cannula size (0.8 mm), as well as of the nurses' documentation in the patient's record. Further efforts to ameliorate care and handling of peripheral intravenous cannulae are needed. This can be done by means of increasing nurses' knowledge and recurrent quality reviews. Well-informed patients can also be more involved in the care than is common today.

[SICI-GISE position paper on the requirements for diagnostic and interventional procedures in patients with peripheral arterial disease].

PubMed

Cremonesi, Alberto; Setacci, Carlo; Rubino, Paolo; Stabile, Eugenio; Castriota, Fausto; Reimers, Bernhard; Inglese, Luigi; Berti, Sergio; Sbarzaglia, Paolo; Biamino, Giancarlo; Guagliumi, Giulio

2013-10-01

Interventional procedures on peripheral vessels are the field of a novel specialty dedicated to the diagnosis and minimally invasive endovascular treatment of diseases involving the cerebral, thoracic and abdominal arteries (including renal and visceral arteries), as well as the peripheral arteries (femoro-popliteal arteries and the arteries below the knee). At present, physicians with three different types of medical training, each involving particular strengths and characteristics, specialize in endovascular treatment of patients with peripheral arterial disease: vascular surgeons, interventional radiologists and interventional cardiologists. Treatment of high-risk patients in terms of anatomical and clinical (serious comorbidities) complexity raised the need for the interventional cardiologist to face issues related to technical aspects of the procedure, multilevel pathology management and adequate indication. To achieve this goal, interventional cardiologists require particular facilities and clinical skills. The objectives of this position paper from the Italian Society of Interventional Cardiology (SICI-GISE) are (i) to define the theoretical background and practical training required to ensure that interventional cardiologists maintain high-quality standards also in the field of treatment of peripheral arterial disease, by establishing shared rules and drafting papers; (ii) to standardize the procedures of interventional cardiology operational units that treat patients with peripheral arterial disease in Italy on the basis of scientific evidence, and (iii) to establish common requirements in terms of facilities and regulations.

Use of peripherally inserted central catheters as an alternative to central catheters in neurocritical care units.

PubMed

DeLemos, Christi; Abi-Nader, Judy; Akins, Paul T

2011-04-01

Patients in neurological critical care units often have lengthy stays that require extended vascular access and invasive hemodynamic monitoring. The traditional approach for these patients has relied heavily on central venous and pulmonary artery catheters. The aim of this study was to evaluate peripherally inserted central catheters as an alternative to central venous catheters in neurocritical care settings. Data on 35 patients who had peripherally inserted central catheters rather than central venous or pulmonary artery catheters for intravascular access and monitoring were collected from a prospective registry of neurological critical care admissions. These data were cross-referenced with information from hospital-based data registries for peripherally inserted central catheters and subarachnoid hemorrhage. Complete data were available on 33 patients with Hunt-Hess grade IV-V aneurysmal subarachnoid hemorrhage. Catheters remained in place a total of 649 days (mean, 19 days; range, 4-64 days). One patient (3%) had deep vein thrombosis in an upper extremity. In 2 patients, central venous pressure measured with a peripherally inserted catheter was higher than pressure measured concurrently with a central venous catheter. None of the 33 patients had a central catheter bloodstream infection or persistent insertion-related complications. CONCLUSIONS Use of peripherally inserted central catheters rather than central venous catheters or pulmonary artery catheters in the neurocritical care unit reduced procedural and infection risk without compromising patient management.

Smooth Muscle Ion Channels and Regulation of Vascular Tone in Resistance Arteries and Arterioles

PubMed Central

Tykocki, Nathan R.; Boerman, Erika M.; Jackson, William F.

2017-01-01

Vascular tone of resistance arteries and arterioles determines peripheral vascular resistance, contributing to the regulation of blood pressure and blood flow to, and within the body’s tissues and organs. Ion channels in the plasma membrane and endoplasmic reticulum of vascular smooth muscle cells (SMCs) in these blood vessels importantly contribute to the regulation of intracellular Ca2+ concentration, the primary determinant of SMC contractile activity and vascular tone. Ion channels provide the main source of activator Ca2+ that determines vascular tone, and strongly contribute to setting and regulating membrane potential, which, in turn, regulates the open-state-probability of voltage gated Ca2+ channels (VGCCs), the primary source of Ca2+ in resistance artery and arteriolar SMCs. Ion channel function is also modulated by vasoconstrictors and vasodilators, contributing to all aspects of the regulation of vascular tone. This review will focus on the physiology of VGCCs, voltage-gated K+ (KV) channels, large-conductance Ca2+-activated K+ (BKCa) channels, strong-inward-rectifier K+ (KIR) channels, ATP-sensitive K+ (KATP) channels, ryanodine receptors (RyRs), inositol 1,4,5-trisphosphate receptors (IP3Rs), and a variety of transient receptor potential (TRP) channels that contribute to pressure-induced myogenic tone in resistance arteries and arterioles, the modulation of the function of these ion channels by vasoconstrictors and vasodilators, their role in the functional regulation of tissue blood flow and their dysfunction in diseases such as hypertension, obesity, and diabetes. PMID:28333380

The reliability of differentiating neurogenic claudication from vascular claudication based on symptomatic presentation.

PubMed

Nadeau, Mélissa; Rosas-Arellano, M Patricia; Gurr, Kevin R; Bailey, Stewart I; Taylor, David C; Grewal, Ruby; Lawlor, D Kirk; Bailey, Chris S

2013-12-01

Intermittent claudication can be neurogenic or vascular. Physicians use a profile based on symptom attributes to differentiate the 2 types of claudication, and this guides their investigations for diagnosis of the underlying pathology. We evaluated the validity of these symptom attributes in differentiating neurogenic from vascular claudication. Patients with a diagnosis of lumbar spinal stenosis (LSS) or peripheral vascular disease (PVD) who reported claudication answered 14 questions characterizing their symptoms. We determined the sensitivity, specificity and positive and negative likelihood ratios (PLR and NLR) for neurogenic and vascular claudication for each symptom attribute. We studied 53 patients. The most sensitive symptom attribute to rule out LSS was the absence of "triggering of pain with standing alone" (sensitivity 0.97, NLR 0.050). Pain alleviators and symptom location data showed a weak clinical significance for LSS and PVD. Constellation of symptoms yielded the strongest associations: patients with a positive shopping cart sign whose symptoms were located above the knees, triggered with standing alone and relieved with sitting had a strong likelihood of neurogenic claudication (PLR 13). Patients with symptoms in the calf that were relieved with standing alone had a strong likelihood of vascular claudication (PLR 20.0). The classic symptom attributes used to differentiate neurogenic from vascular claudication are at best weakly valid independently. However, certain constellation of symptoms are much more indicative of etiology. These results can guide general practitioners in their evaluation of and investigation for claudication.

Continuous exposure to low amplitude extremely low frequency electrical fields characterizing the vascular streaming potential alters elastin accumulation in vascular smooth muscle cells.

PubMed

Bergethon, Peter R; Kindler, Dean D; Hallock, Kevin; Blease, Susan; Toselli, Paul

2013-07-01

In normal development and pathology, the vascular system depends on complex interactions between cellular elements, biochemical molecules, and physical forces. The electrokinetic vascular streaming potential (EVSP) is an endogenous extremely low frequency (ELF) electrical field resulting from blood flowing past the vessel wall. While generally unrecognized, it is a ubiquitous electrical biophysical force to which the vascular tree is exposed. Extracellular matrix elastin plays a central role in normal blood vessel function and in the development of atherosclerosis. It was hypothesized that ELF fields of low amplitude would alter elastin accumulation, supporting a link between the EVSP and the biology of vascular smooth muscle cells. Neonatal rat aortic smooth muscle cell cultures were exposed chronically to electrical fields characteristic of the EVSP. Extracellular protein accumulation, DNA content, and electron microscopic (EM) evaluation were performed after 2 weeks of exposure. Stimulated cultures showed no significant change in cellular proliferation as measured by the DNA concentration. The per-DNA normalized protein in the extracellular matrix was unchanged while extracellular elastin accumulation decreased 38% on average. EM analysis showed that the stimulated cells had a 2.85-fold increase in mitochondrial number. These results support the formulation that ELF fields are a potential factor in both normal vessel biology and in the pathogenesis of atherosclerotic diseases including heart disease, stroke, and peripheral vascular disease. Copyright © 2013 Wiley Periodicals, Inc.

[Contrast enhanced power Doppler and color Doppler ultrasound in breast masses: Efficiency in diagnosis and contributions to differential diagnosis].

PubMed

Algül, Ali; Balci, Pinar; Seçil, Mustafa; Canda, Tülay

2003-06-01

To compare ability of detection of vascular structures by utilizing ultrasonographic contrast agent (Levovist) prior to and following power Doppler ultrasound (PDUS) and colour Doppler ultrasound (CDUS) and to determine useful parameters in the differentiation of malignant and benign breast masses by means of verified data. Vascularisation characteristics of 38 breast masses (22 malignant, 16 benign) which were confirmed by mammography and B-mode sonography were evaluated by both CDUS and PDUS following and prior to intravenous contrast application. In addition, Vmax and RI values of vascular structures were calculated by Doppler spectral evaluation. Malignant lesions showed more vascularity than benign lesions both with and without contrast enhancement. With both methods, by utilizing contrast agent, central, penetrating and tortuous vascular structures became more significant in malignant lesions when compared with benign lesions. PDUS was able to detect vascular structures better than CDUS; however, the difference was not statistically significant. Presence of peripheral vascularity was not useful in differentiating malignant from benign lesions. Vmax and RI values were higher in malignant lesions and the difference was statistically significant. In both methods, Vmax > 15 cm/sec and RI > 0.80 (CDUS), and RI > 0.70 (PDUS) were accepted as malignancy parameters. Vascular patterns of breast masses as determined with PDUS and CDUS with contrast enhancement and Doppler spectral examinations enabled differentiation of malignant and benign breast lesions. Thus, it is possible to decrease the number of unnecessary surgical interventions.

Vascular wall progenitor cells in health and disease.

PubMed

Psaltis, Peter J; Simari, Robert D

2015-04-10

The vasculature plays an indispensible role in organ development and maintenance of tissue homeostasis, such that disturbances to it impact greatly on developmental and postnatal health. Although cell turnover in healthy blood vessels is low, it increases considerably under pathological conditions. The principle sources for this phenomenon have long been considered to be the recruitment of cells from the peripheral circulation and the re-entry of mature cells in the vessel wall back into cell cycle. However, recent discoveries have also uncovered the presence of a range of multipotent and lineage-restricted progenitor cells in the mural layers of postnatal blood vessels, possessing high proliferative capacity and potential to generate endothelial, smooth muscle, hematopoietic or mesenchymal cell progeny. In particular, the tunica adventitia has emerged as a progenitor-rich compartment with niche-like characteristics that support and regulate vascular wall progenitor cells. Preliminary data indicate the involvement of some of these vascular wall progenitor cells in vascular disease states, adding weight to the notion that the adventitia is integral to vascular wall pathogenesis, and raising potential implications for clinical therapies. This review discusses the current body of evidence for the existence of vascular wall progenitor cell subpopulations from development to adulthood and addresses the gains made and significant challenges that lie ahead in trying to accurately delineate their identities, origins, regulatory pathways, and relevance to normal vascular structure and function, as well as disease. © 2015 American Heart Association, Inc.

Risk factors for vascular complications and treatment patterns at diagnosis of 2389 PV and ET patients: Real-world data from the Swedish MPN Registry.

PubMed

Abdulkarim, Khadija; Samuelsson, Jan; Johansson, Peter; Andréasson, Björn

2017-06-01

The study mainly aimed at investigating possible correlations between peripheral blood counts, erythropoietin (EPO), JAK2 V617F mutation, and vascular complications prior to diagnosis of a population-based cohort of newly diagnosed patients with myeloproliferative neoplasms (MPN). The study comprises 1105 patients with polycythemia vera (PV) and 1284 patients with essential thrombocythemia (ET) registered in the Swedish MPN Registry. Vascular complications, prior to diagnosis, were registered in 37% of PV patients. In multivariate analysis, low hemoglobin was the only significant risk factor (P=.0120). Among ET patients, 35% had encountered a vascular complication. Risk factors for thromboembolic complications in ET were identified as age>65 years, white cell count>12×10 9 /L, and the presence of JAK2 V617F mutation (P=.0004, P=.0038, and P=.0016, respectively). A JAK2 V617F mutation was present in 71% of ET patients with vascular complications, compared to 60% in patients without. A majority of complications were thromboembolic, in both PV and ET. We conclude that vascular complications among newly diagnosed patients had affected more than one-third of our study population. Risk factors for vascular complications prior to diagnosis were lower hemoglobin in PV, and the presence of JAK2 V617F mutation, higher age, and leukocytosis in ET. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Salmonella Typhimurium gastroenteritis leading to chronic prosthetic vascular graft infection.

PubMed

Cullinan, Milo; Clarke, Michael; Dallman, Tim; Peart, Steven; Wilson, Deborah; Weiand, Daniel

2017-08-01

Introduction. It is estimated up to 6 % of prosthetic vascular grafts become infected. Staphylococcus aureus is predominant in early infection and coagulase-negative staphylococci are predominant in late infections. Enterobacteriaceae cause 14-40 % of prosthetic vascular graft infections. This is, to our knowledge the first reported case of Salmonella gastroenteritis causing chronic prosthetic vascular graft infection (PVGI). Case presentation. A 57 years old lady presented with signs and symptoms of prosthetic vascular graft infection. Three years earlier, she had undergone a prosthetic axillo-femoral bypass graft for critical limb ischaemia. The infected prosthetic vascular graft was removed and Salmonella Typhimurium was isolated on culture. In the intervening period, Salmonella Typhimurium was isolated from a faecal specimen, collected during an episode of acute gastroenteritis. Whole-genome sequencing (WGS) showed that the respective Salmonella Typhimurium isolates differed by only a single nucleotide polymorphism (SNP). Salmonella Typhimurium was not isolated on culture of a faecal specimen collected five days following cessation of antimicrobial therapy. Six months after removal of the prosthetic graft, the patient remains under follow-up for her peripheral vascular disease, which currently requires no further surgical intervention. Conclusion. This case has clear implications for the management of chronic PVGI. It is vital to collect high-quality surgical specimens for microbiological analysis and empirical choices of antibiotics are unlikely to cover all potential pathogens. It may also be prudent to enquire about a history of acute gastroenteritis when assessing patients presenting with chronic PVGI.

Destructive effect of HIFU on rabbit embedded endometrial carcinoma tissues and their vascularities

PubMed Central

Guan, Liming; Xu, Gang

2017-01-01

Objectives To evaluate damage effect of High-intensity focused ultrasound on early stage endometrial cancer tissues and their vascularities. Materials and Methods Rabbit endometrial cancer models were established via tumor blocks implantation for a prospective control study. Ultrasonic ablation efficacy was evaluated by pathologic and imaging changes. The target lesions of experimental rabbits before and after ultrasonic ablation were observed after autopsy. The slides were used for hematoxylin-eosin staining, elastic fiber staining and endothelial cell staining; the slides were observed by optical microscopy. One slide was observed by electron microscopy. Then the target lesions of experimental animals with ultrasonic ablation were observed by vascular imaging, one group was visualized by digital subtract angiography, one group was quantified by color Doppler flow imaging, and one group was detected by dye perfusion. SPSS 19.0 software was used for statistical analyses. Results Histological examination indicated that High-intensity focused ultrasound caused the tumor tissues and their vascularities coagulative necrosis. Tumor vascular structure components including elastic fiber, endothelial cells all were destroyed by ultrasonic ablation. Digital subtract angiography showed tumor vascular shadow were dismissed after ultrasonic ablation. After ultrasonic ablation, gray-scale of tumor nodules enhanced in ultrasonography, tumor peripheral and internal blood flow signals disappeared or significantly reduced in color Doppler flow imaging. Vascular perfusion performed after ultrasonic ablation, tumor vessels could not filled by dye liquid. Conclusion High-intensity focused ultrasound as a noninvasive method can destroy whole endometrial cancer cells and their supplying vascularities, which maybe an alternative approach of targeted therapy and new antiangiogenic strategy for endometrial cancer. PMID:28121624

Destructive effect of HIFU on rabbit embedded endometrial carcinoma tissues and their vascularities.

PubMed

Guan, Liming; Xu, Gang

2017-03-21

To evaluate damage effect of High-intensity focused ultrasound on early stage endometrial cancer tissues and their vascularities. Rabbit endometrial cancer models were established via tumor blocks implantation for a prospective control study. Ultrasonic ablation efficacy was evaluated by pathologic and imaging changes. The target lesions of experimental rabbits before and after ultrasonic ablation were observed after autopsy. The slides were used for hematoxylin-eosin staining, elastic fiber staining and endothelial cell staining; the slides were observed by optical microscopy. One slide was observed by electron microscopy. Then the target lesions of experimental animals with ultrasonic ablation were observed by vascular imaging, one group was visualized by digital subtract angiography, one group was quantified by color Doppler flow imaging, and one group was detected by dye perfusion.SPSS 19.0 software was used for statistical analyses. Histological examination indicated that High-intensity focused ultrasound caused the tumor tissues and their vascularities coagulative necrosis. Tumor vascular structure components including elastic fiber, endothelial cells all were destroyed by ultrasonic ablation. Digital subtract angiography showed tumor vascular shadow were dismissed after ultrasonic ablation. After ultrasonic ablation, gray-scale of tumor nodules enhanced in ultrasonography, tumor peripheral and internal blood flow signals disappeared or significantly reduced in color Doppler flow imaging. Vascular perfusion performed after ultrasonic ablation, tumor vessels could not filled by dye liquid. High-intensity focused ultrasound as a noninvasive method can destroy whole endometrial cancer cells and their supplying vascularities, which maybe an alternative approach of targeted therapy and new antiangiogenic strategy for endometrial cancer.

Social network composition of vascular patients and its associations with health behavior and clinical risk factors

PubMed Central

Heijmans, Naomi; van Lieshout, Jan; Wensing, Michel

2017-01-01

Background This study aimed to explore linkages of patients’ social network composition with health behaviors and clinical risk factors. Methods/Design This observational study was embedded in a project aimed at improving cardiovascular risk management (CRVM) in primary care. 657 vascular patients (227 with cardiovascular disease, 380 at high vascular risk), mean age 72.4 (SD 9.4) years, were recruited as were individuals patients considered important for dealing with their disease, so called alters (n = 487). Network composition was measured with structured patient questionnaires. Both patients and alters completed questionnaires to measure health behavior (habits for physical activity, diet, and smoking). Clinical risk factors (systolic blood pressure, LDL cholesterol level, and body mass index) were extracted from patients’ medical records. Six logistic regression analyses, using generalized estimating equations, were used to test three hypothesized effects of network composition (having alters with healthful behaviors, without depression, and with specialized knowledge) on six outcomes, adjusted for demographic, personal and psychological characteristics. Results Having alters with overall healthful behavior was related to healthful patient diet (OR 2.14, 95%CI: 1.52–3.02). Having non-smoking alters in networks was related to reduced odds for patient smoking (OR 0.17, 95%CI: 0.05–0.60). No effects of presence of non-depressed alters were found. Presence of alters with specialized knowledge on CVRM was inversely related to healthful diet habits of patients (OR 0.47, 95%CI 0.24–0.89). No significant associations between social network composition and clinical risk factors were found. Discussion Diet and smoking, but not physical exercise and clinical risk factors, were associated with social network composition of patients with vascular conditions. In this study of vascular patients, controlling for both personal and psychological factors, fewer network influences were found compared to previous research. Further research is needed to examine network structure characteristics as well as the role of psychological factors to enhance understanding health behavior of patients involved in CVRM. PMID:28957372

Vascular Trauma Operative Experience is Inadequate in General Surgery Programs.

PubMed

Yan, Huan; Maximus, Steven; Koopmann, Matthew; Keeley, Jessica; Smith, Brian; Virgilio, Christian de; Kim, Dennis Y

2016-05-01

Vascular injuries may be challenging, particularly for surgeons who have not received formal vascular surgery fellowship training. Lack of experience and improper technique can result in significant complications. The objective of this study was to examine changes in resident experience with operative vascular trauma over time. A retrospective review was performed using Accreditation Council for Graduate Medical Education (ACGME) case logs of general surgery residents graduating between 2004 and 2014 at 2 academic, university-affiliated institutions associated with level 1 trauma centers. The primary outcome was number of reported vascular trauma operations, stratified by year of graduation and institution. A total of 112 residents graduated in the study period with a median 7 (interquartile range 4.5-13.5) vascular trauma cases per resident. Fasciotomy and exposure and/or repair of peripheral vessels constituted the bulk of the operative volume. Linear regression showed no significant trend in cases with respect to year of graduation (P = 0.266). Residents from program A (n = 53) reported a significantly higher number of vascular trauma cases when compared with program B (n = 59): 12.0 vs. 5.0 cases, respectively (P < 0.001). Level 1 trauma center verification does not guarantee sufficient exposure to vascular trauma. The operative exposure in program B is reflective of the national average of 4.0 cases per resident as reported by the ACGME, and this trend is unlikely to change in the near future. Fellowship training may be critical for surgeons who plan to work in a trauma setting, particularly in areas lacking vascular surgeons. Copyright © 2016 Elsevier Inc. All rights reserved.

Sensory and motor peripheral nerve function and lower-extremity quadriceps strength: the health, aging and body composition study.

PubMed

Strotmeyer, Elsa S; de Rekeneire, Nathalie; Schwartz, Ann V; Resnick, Helaine E; Goodpaster, Bret H; Faulkner, Kimberly A; Shorr, Ronald I; Vinik, Aaron I; Harris, Tamara B; Newman, Anne B

2009-11-01

To determine whether sensory and motor nerve function is associated cross-sectionally with quadriceps or ankle dorsiflexion strength in an older community-based population. Cross-sectional analyses within a longitudinal cohort study. Two U.S. clinical sites. Two thousand fifty-nine Health, Aging and Body Composition Study (Health ABC) participants (49.5% male, 36.7% black, aged 73-82) in 2000/01. Quadriceps and ankle strength were measured using an isokinetic dynamometer. Sensory and motor peripheral nerve function in the legs and feet was assessed using 10-g and 1.4-g monofilaments, vibration threshold, and peroneal motor nerve conduction amplitude and velocity. Monofilament insensitivity, poorest vibration threshold quartile (>60 mu), and poorest motor nerve conduction amplitude quartile (<1.7 mV) were associated with 11%, 7%, and 8% lower quadriceps strength (all P<.01), respectively, than in the best peripheral nerve function categories in adjusted linear regression models. Monofilament insensitivity and lowest amplitude quartile were both associated with 17% lower ankle strength (P<.01). Multivariate analyses were adjusted for demographic characteristics, diabetes mellitus, body composition, lifestyle factors, and chronic health conditions and included all peripheral nerve measures in the same model. Monofilament insensitivity (beta=-7.19), vibration threshold (beta=-0.097), and motor nerve conduction amplitude (beta=2.01) each contributed independently to lower quadriceps strength (all P<.01). Monofilament insensitivity (beta=-5.29) and amplitude (beta=1.17) each contributed independently to lower ankle strength (all P<.01). Neither diabetes mellitus status nor lean mass explained the associations between peripheral nerve function and strength. Reduced sensory and motor peripheral nerve function is related to poorer lower extremity strength in older adults, suggesting a mechanism for the relationship with lower extremity disability.

Transcription factor fos-related antigen-2 induces progressive peripheral vasculopathy in mice closely resembling human systemic sclerosis.

PubMed

Maurer, Britta; Busch, Nicole; Jüngel, Astrid; Pileckyte, Margarita; Gay, Renate E; Michel, Beat A; Schett, Georg; Gay, Steffen; Distler, Jörg; Distler, Oliver

2009-12-08

Microvascular damage is one of the first pathological changes in systemic sclerosis. In this study, we investigated the role of Fos-related antigen-2 (Fra-2), a transcription factor of the activator protein-1 family, in the peripheral vasculopathy of systemic sclerosis and examined the underlying mechanisms. Expression of Fra-2 protein was significantly increased in skin biopsies of systemic sclerosis patients compared with healthy controls, especially in endothelial and vascular smooth muscle cells. Fra-2 transgenic mice developed a severe loss of small blood vessels in the skin that was paralleled by progressive skin fibrosis at 12 weeks of age. The reduction in capillary density was preceded by a significant increase in apoptosis in endothelial cells at week 9 as detected by immunohistochemistry. Similarly, suppression of Fra-2 by small interfering RNA prevented human microvascular endothelial cells from staurosporine-induced apoptosis and improved both the number of tubes and the cumulative tube lengths in the tube formation assay. In addition, cell migration in the scratch assay and vascular endothelial growth factor-dependent chemotaxis in a modified Boyden chamber assay were increased after transfection of human microvascular endothelial cells with Fra-2 small interfering RNA, whereas proliferation was not affected. Fra-2 is present in human systemic sclerosis and may contribute to the development of microvasculopathy by inducing endothelial cell apoptosis and by reducing endothelial cell migration and chemotaxis. Fra-2 transgenic mice are a promising preclinical model to study the mechanisms and therapeutic approaches of the peripheral vasculopathy in systemic sclerosis.

Analysis of novel cardiovascular biomarkers in patients with peripheral artery disease (PAD).

PubMed

Jirak, Peter; Mirna, Moritz; Wernly, Bernhard; Paar, Vera; Thieme, Marcus; Betge, Stefan; Franz, Marcus; Hoppe, Uta; Lauten, Alexander; Kammler, Jürgen; Schulze, Paul C; Lichtenauer, Michael; Kretzschmar, Daniel

2018-04-12

Peripheral artery disease (PAD) is a common form of manifestation of atherosclerosis. PAD has a considerable impact on morbidity, hospitalisation rates and health- care costs. Biomarkers have been introduced in many cardiovascular disease entities over the last years. However, an analysis on the correlation of biomarker levels and PAD is still lacking. A total of 106 patients were enrolled in this current study, 51 that were diagnosed with PAD and 55 with excluded coronary and peripheral artery disease as controls. During outpatient visits, plasma samples of all patients were obtained and analyzed for sST2 (hemodynamics and inflammation), Galectin-3 (fibrosis and remodeling), GDF-15 (remodeling and inflammation), suPAR (inflammation), and Fetuin-A (vascular calcification) by use of ELISA after informed consent. Compared with controls, patients with PAD showed significantly higher levels of sST2 (5248 vs. 7503 pg/ml, p<0.001), suPAR (2267 vs. 2414 pg/ml, p=0.02), Galectin-3 (2795 vs. 4494 pg/ml, p<0.001), and GDF-15 (549 vs. 767 pg/ml, p<0.001). Fetuin-A showed a trend towards lower levels in patients with PAD (117 vs. 100 ng/ml, p=0.119). Circulating levels of sST2, suPAR, Galectin-3, and GDF-15 were significantly elevated in PAD patients. In contrast, Fetuin-A levels showed a decrease in PAD patients indicating increased vascular calcification. Thus, by incorporating different pathophysiological processes present in PAD, tested novel biomarkers facilitate a more precise diagnosis as well as a more accurate evaluation of disease severity and progression.

Frequency of cancer in patients operated on for acute peripheral arterial thrombosis and the impact on prognosis.

PubMed

Nicolajsen, Chalotte Winther; Dickenson, Maja Holch; Budtz-Lilly, Jacob; Eldrup, Nikolaj

2015-12-01

Little is known about acute peripheral arterial thrombosis in patients with concomitant cancer. Small studies suggest that revascularization in this patient group is associated with thrombosis and increased risk of amputation and death. We investigated the frequency of cancer in patients operated on for acute peripheral arterial thrombosis and the long-term risk of amputation, mortality, myocardial infarction, and stroke in a national cohort. This was a prospective case/noncase study comprising all Danish citizens undergoing vascular surgery for acute arterial thrombosis from 1986 to 2012 with up to 26 years of follow-up. A total of 7840 patients were treated surgically for acute arterial thrombosis; 2384 (30.4%) were previously diagnosed with cancer or developed cancer during the observation period. Risk of amputation was not significantly different in patients with or without cancer, except in patients with cancer diagnosed <24 months before acute limb ischemia (hazard ratio, 2.0). Mortality was significantly greater in all patients having or developing cancer within 24 months after surgery (hazard ratio, 1.2-2.2). The frequencies of myocardial infarction and stroke were similar to those among patients without cancer. One of five patients operated on for acute limb ischemia has a diagnosis of cancer, and a further 3.4% will develop cancer within 24 months. The data further show that patients with acute limb ischemia and concomitant cancer can be successfully revascularized and that the majority of these patients preserve their limb. Cancer should therefore not contravene interventional treatment. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

[Retinopathy of prematurity].

PubMed

Promelle, V; Milazzo, S

2017-05-01

Retinopathy of prematurity is a retinal vasoproliferative disease affecting extremely preterm infants exposed to high concentrations of oxygen therapy. Infants born before 32 post-menstrual weeks or with a birth weight of less than 1500g should systematically have a dilated fundus examination. The time of screening and schedule for follow-up are guided by the various risk factors. This disease results from immaturity of the peripheral retinal vessels at the time of premature birth. The classification of ROP depends on the anteroposterior extent of involvement (from center to periphery: zone I, II and III), its extension in 30° sectors (clock hours) and its stage (stage 1 to 5). "Plus" disease is defined as dilation and tortuosity of the retinal blood vessels in the posterior pole of the eye and represents a major risk factor for rapid unfavorable progression. A majority of patients will spontaneously recover, but patients with a high risk of progression will require treatment to prevent retinal detachment and blindness. The indications for treatment are threshold disease and type 1 pre-threshold disease. The current treatment of choice is peripheral retinal ablation with transpupillary laser, but ab externo cryotherapy may be used instead. Intravitreal injection of vascular endothelial growth factor inhibitors may be an attractive therapeutic option and is currently under investigation. After laser treatment, unfavorable outcomes occur in only 9 to 14 % of eyes, but at the price of peripheral retinal destruction. For all patients, whether treated or not, a regular fundus examination should be insured until complete retinal vascularization has occurred. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Flow-mediated dilation and peripheral arterial tonometry are disturbed in preeclampsia and reflect different aspects of endothelial function.

PubMed

Mannaerts, Dominique; Faes, Ellen; Goovaerts, Inge; Stoop, Tibor; Cornette, Jerome; Gyselaers, Wilfried; Spaanderman, Marc; Van Craenenbroeck, Emeline M; Jacquemyn, Yves

2017-11-01

Endothelial function and arterial stiffness are known to be altered in preeclamptic pregnancies. Previous studies have shown conflicting results regarding the best technique for assessing vascular function in pregnancy. In this study, we made a comprehensive evaluation of in vivo vascular function [including flow-mediated dilatation (FMD), peripheral arterial tonometry (PAT), and arterial stiffness] in preeclamptic patients and compared them with normal pregnancies. In addition, we assessed the relation between vascular function and systemic inflammation. Fourteen patients with preeclampsia (PE) and 14 healthy pregnant controls were included. Endothelial function was determined by FMD and PAT and arterial stiffness by carotid-femoral pulse-wave velocity and augmentation index. Systemic inflammation was assessed using mean platelet volume (MPV) and neutrophil-lymphocyte ratio (NLR). The reactive hyperemia index, assessed using PAT, is decreased at the third trimester compared with the first trimester in a normal, uncomplicated pregnancy ( P = 0.001). Arterial stiffness is significantly higher in PE versus normal pregnancy ( P < 0.001). Endothelial function, obtained by FMD, is deteriorated in PE versus normal pregnancy ( P = 0.015), whereas endothelial function assessment by PAT is improved in PE versus normal pregnancy ( P = 0.001). Systemic inflammation (MPV and NLR) increases during normal pregnancy. FMD and PAT are disturbed in PE. Endothelial function, assessed by FMD and PAT, shows distinct results. This may indicate that measurements with FMD and PAT reflect different aspects of endothelial function and that PAT should not be used as a substitute for FMD as a measure of endothelial function in pregnancy. Copyright © 2017 the American Physiological Society.

Microfibrillar-associated protein 4 variation in symptomatic peripheral artery disease.

PubMed

Hemstra, Line Ea; Schlosser, Anders; Lindholt, Jes Sanddal; Sorensen, Grith L

2018-06-08

Symptomatic peripheral artery disease (PAD) is an atherosclerotic occlusive disease affecting the lower extremities. The cause of symptomatic PAD is atherosclerosis, vascular dysfunctions, impaired angiogenesis and neointima formation. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein, which is highly expressed in the heart and arteries and recently introduced as a potential mediator of pathological vascular remodeling and neointima formation. We aimed to investigate the relationship between serum MFAP4 (sMFAP4) and symptomatic PAD outcomes. A total of 286 PAD patients were analyzed if they had either intermittent claudication or critical lower-extremity ischemia (CLI) and followed for 7 years. The level of serum MFAP4 (sMFAP4) was measured by alphaLISA. Kaplan-Meier, Cox proportional hazard and logistic regression analysis were used to analyze the associations between upper tertile sMFAP4 and symptomatic PAD outcomes. Patients with upper tertile sMFAP4 had an odds ratio (OR) of 2.65 (p < 0.001) for having CLI diagnosis. Further analysis indicated that patients with upper tertile sMFAP4 had a hazard ratio (HR) of 1.97 (p = 0.04) for cardiovascular death during the 7-years follow-up. However, analysis of 2-year primary patency showed that patients with upper tertile sMFAP4 had decreased risk of vascular occlusion after reconstructive surgery with HR of 0.15 (p = 0.02). sMFAP4 has potential as a prognostic marker for cardiovascular death, primary patency of reconstructed vessels and CLI diagnosis in symptomatic PAD patients. Confirmation of observations in larger cohorts is warranted.

Rating scale for the assessment of competence in ultrasound-guided peripheral vascular access - a Delphi Consensus Study.

PubMed

Primdahl, Stine C; Todsen, Tobias; Clemmesen, Louise; Knudsen, Lars; Weile, Jesper

2016-09-21

Peripheral vascular access is vital for treatment and diagnostics of hospitalized patients. Ultrasound-guided vascular access (UGVA) is superior to the landmark technique. To ensure competence-based education, an assessment tool of UGVA competence is needed. We aimed to develop a global rating scale (RS) for assessment of UGVA competence based on opinions on the content from ultrasound experts in a modified Delphi consensus study. We included experts from anesthesiology, emergency medicine and radiology across university hospitals in Denmark. Nine elements were drafted based on existing literature and recommendations from international societies. In a multi-round survey, the experts rated the elements on a five-point Likert scale according to importance, and suggested missing elements. The final Delphi round occurred when >80% of the experts rated all elements ≥4 on the Likert scale. Sixteen experts consented to participate in the study, one withdrew consent prior to the first Delphi round, and 14 completed all three Delphi rounds. In the first Delphi round the experts excluded one element from the scale and changed the content of two elements. In the second Delphi round, the experts excluded one element from the scale. In the third Delphi round, consensus was obtained on the eight elements: preparation of utensils, ergonomics, preparation of the ultrasound device, identification of blood vessels, anatomy, hygiene, coordination of the needle, and completion of the procedure. We developed an RS for assessment of UGVA competence based on opinions of ultrasound experts through a modified Delphi consensus study.

The consequence of biologic graft processing on blood interface biocompatibility and mechanics.

PubMed

Van de Walle, Aurore B; Uzarski, Joseph S; McFetridge, Peter S

2015-09-01

Processing ex vivo derived tissues to reduce immunogenicity is an effective approach to create biologically complex materials for vascular reconstruction. Due to the sensitivity of small diameter vascular grafts to occlusive events, the effect of graft processing on critical parameters for graft patency, such as peripheral cell adhesion and wall mechanics, requires detailed analysis. Isolated human umbilical vein sections were used as model allogenic vascular scaffolds that were processed with either: 1. sodium dodecyl sulfate (SDS), 2. ethanol/acetone (EtAc), or 3. glutaraldehyde (Glu). Changes in material mechanics were assessed via uniaxial tensile testing. Peripheral cell adhesion to the opaque grafting material was evaluated using an innovative flow chamber that allows direct observation of the blood-graft interface under physiological shear conditions. All treatments modified the grafts tensile strain and stiffness properties, with physiological modulus values decreasing from Glu 240±12 kPa to SDS 210±6 kPa and EtAc 140±3 kPa, P<.001. Relative to glutaraldehyde treatments, neutrophil adhesion to the decellularized grafts increased, with no statistical difference observed between SDS or EtAc treatments. Early platelet adhesion (% surface coverage) showed no statistical difference between the three treatments; however, quantification of platelet aggregates was significantly higher on SDS scaffolds compared to EtAc or Glu. Tissue processing strategies applied to the umbilical vein scaffold were shown to modify structural mechanics and cell adhesion properties, with the EtAc treatment reducing thrombotic events relative to SDS treated samples. This approach allows time and cost effective prescreening of clinically relevant grafting materials to assess initial cell reactivity.

Numerical assessment of the stiffness index.

PubMed

Epstein, Sally; Vergnaud, Anne-Claire; Elliott, Paul; Chowienczyk, Phil; Alastruey, Jordi

2014-01-01

Elevated systemic vascular stiffness is associated with increased risk of cardiovascular disease. It has been suggested that the time difference between the two characteristic peaks of the digital volume pulse (DVP) measured at the finger using photoplethysmography is related to the stiffness of the arterial tree, and inversely proportional to the stiffness index (SI). However, the precise physical meaning of the SI and its relation to aortic pulse wave velocity (aPWV) is yet to be ascertained. In this study we investigated numerically the effect of changes in arterial wall stiffness, peripheral resistances, peripheral compliances or peripheral wave reflections on the SI and aPWV. The SI was calculated from the digital area waveform simulated using a nonlinear one-dimensional model of pulse wave propagation in a 75-artery network, which includes the larger arteries of the hand. Our results show that aPWV is affected by changes in aortic stiffness, but the SI is primarily affected by changes in the stiffness of all conduit vessels. Thus, the SI is not a direct substitute for aPWV. Moreover, our results suggest that peripheral reflections in the upper body delay the time of arrival of the first peak in the DVP. The second peak is predominantly caused by the impedance mismatch within the 75 arterial segments, rather than by peripheral reflections.

Sleep-Disordered Breathing and Cardiovascular Correlates in College Football Players.

PubMed

Kim, Jonathan H; Hollowed, Casey; Irwin-Weyant, Morgan; Patel, Keyur; Hosny, Kareem; Aida, Hiroshi; Gowani, Zaina; Sher, Salman; Gleason, Patrick; Shoop, James L; Galante, Angelo; Clark, Craig; Ko, Yi-An; Quyyumi, Arshed A; Collop, Nancy A; Baggish, Aaron L

2017-10-15

This study sought to determine the cardiovascular physiologic correlates of sleep-disordered breathing (SDB) in American-style football (ASF) participants using echocardiography, vascular applanation tonometry, and peripheral arterial tonometry. Forty collegiate ASF participants were analyzed at pre- and postseason time points with echocardiography and vascular applanation tonometry. WatchPAT (inclusive of peripheral arterial tonometry) used to assess for SDB was then performed at the postseason time point. Twenty-two of 40 (55%) ASF participants demonstrated SDB with an apnea-hypopnea index (pAHI) ≥5. ASF participants with SDB were larger (109 ± 20 vs 92 ± 14 kg, p = 0.004) and more likely linemen position players (83% vs 50%, p = 0.03). Compared with those without SDB, ASF participants with SDB demonstrated relative impairments in left ventricular diastolic and vascular function as reflected by lower lateral e' (14 ± 3 vs 17 ± 3 cm/s, p = 0.007) and septal e' (11 ± 2 vs 13 ± 2 cm/s, p = 0.009) tissue velocities and higher pulse wave velocity (5.4 ± 0.9 vs 4.8 ± 0.5 m/s, p = 0.02). In the total cohort, there were significant positive correlations between pAHI and pulse wave velocity (r = 0.42, p = 0.008) and inverse correlations between pAHI and the averaged e' tissue velocities (r = -0.42, p = 0.01). In conclusion, SDB is highly prevalent in youthful collegiate ASF participants and associated with relative impairments in cardiac and vascular function. Targeted efforts to identify youthful populations with SDB, including ASF participants, and implement SDB treatment algorithms, represent important future clinical directives. Copyright © 2017 Elsevier Inc. All rights reserved.

The free-radical scavenger, edaravone, augments NO release from vascular cells and platelets after laser-induced, acute endothelial injury in vivo.

PubMed

Yamashita, T; Shoge, M; Oda, E; Yamamoto, Y; Giddings, J C; Kashiwagi, S; Suematsu, M; Yamamoto, J

2006-05-01

In vitro and in vivo experimental models have demonstrated that vascular endothelial function is significantly impaired as a result of oxidative stress, mediated by the generation of oxygen-derived free radicals in response to chronic or acute inflammation. In particular, super-oxide () at specific concentrations leads to the impairment of nitric oxide (NO) bioactivity, and it is known that NO plays a fundamental role in the maintenance of vascular homeostasis. The relationship between reactive oxygen species (ROS) and NO release in thrombosis-related endothelial damage in the peripheral microvasculature remains unclear, however. The purpose of the present study was to investigate the effect of the free-radical scavenger, edaravone, on NO synthesis and thrombotic potential in arterioles after exposure to laser irradiation. Highly sensitive electrochemical NO microsensors were positioned in femoral arterioles of mice, and the kinetics of NO release were recorded in response to standardized laser irradiation in vivo. In addition, images of NO release from damaged vascular cells were investigated in a similar rat model using the NO-sensitive dye 4,5-diaminofluorescein diacetate (DAF-2DA). Thrombogenesis was assessed in carotid arterioles by continuous video microscopy using image analysis software. Laser irradiation led to NO release from perturbed endothelial cells and from platelet-rich thrombi. Edaravone had no significant effect on NO release in non-laser treated, intact endothelium compared with placebo. In contrast, edaravone demonstrated a dose-dependent effect on NO release and thrombogenicity. At a concentration of 10.5 mg/kg per h, edaravone promoted a 5-fold increase in NO and a reduction in platelet-rich thrombus volume to 58% of the placebo values. Our data provide direct evidence to confirm that acute endothelial damage in peripheral microvessels initially induces NO release and that the free-radical scavenger, edaravone, augments NO synthesis leading to suppression of platelet thrombus formation.

Impact of biological soil crusts and desert plants on soil microfaunal community composition

USGS Publications Warehouse

Darby, B.J.; Neher, D.A.; Belnap, J.

2010-01-01

Carbon and nitrogen are supplied by a variety of sources in the desert food web; both vascular and non-vascular plants and cyanobacteria supply carbon, and cyanobacteria and plant-associated rhizosphere bacteria are sources of biological nitrogen fixation. The objective of this study was to compare the relative influence of vascular plants and biological soil crusts on desert soil nematode and protozoan abundance and community composition. In the first experiment, biological soil crusts were removed by physical trampling. Treatments with crust removed had fewer nematodes and a greater relative ratio of bacterivores to microphytophages than treatments with intact crust. However, protozoa composition was similar with or without the presence of crusts. In a second experiment, nematode community composition was characterized along a spatial gradient away from stems of grasses or shrubs. Although nematodes generally occurred in increasing abundance nearer to plant stems, some genera (such as the enrichment-type Panagrolaimus) increased disproportionately more than others (such as the stress-tolerant Acromoldavicus). We propose that the impact of biological soil crusts and desert plants on soil microfauna, as reflected in the community composition of microbivorous nematodes, is a combination of carbon input, microclimate amelioration, and altered soil hydrology. ?? Springer Science + Business Media B.V. 2009.

Fabrication and spin tests of composite flywheels

NASA Astrophysics Data System (ADS)

Hamamoto, A.; Inutake, T.; Kogai, K.

Energy storage flywheels consisting of carbon fiber epoxy composite rims and aluminum or carbon fabric cloth epoxy composite hubs were designed, fabricated and tested. The composite rims were 38O mm in outer diameter and 300 mm in inner diameter with a thickness of 25 mm. The test rotor with a aluminum hub was spun to maximum peripheral speed of 982 m/s on burst test. This corresponds to an energy density, based upon total rotor weight, of approximately 71 Wh/kg. Another rotor, made use of a four rims configuration, was tested to 800 m/s successfully with no damage and no dynamic problem. The energy stored in the rotor is more than 500 Wh and the energy density is about 55 Wh/kg at that speed. The rotor with a composite hub was tested to the peripheral speed of 820 m/s. It was restricted by rotor dynamic problems.

Hybrid use of combined and sequential delivery of growth factors and ultrasound stimulation in porous multilayer composite scaffolds to promote both vascularization and bone formation in bone tissue engineering.

PubMed

Yan, Haoran; Liu, Xia; Zhu, Minghua; Luo, Guilin; Sun, Tao; Peng, Qiang; Zeng, Yi; Chen, Taijun; Wang, Yingying; Liu, Keliang; Feng, Bo; Weng, Jie; Wang, Jianxin

2016-01-01

In this study, a multilayer coating technology would be adopted to prepare a porous composite scaffold and the growth factor release and ultrasound techniques were introduced into bone tissue engineering to finally solve the problems of vascularization and bone formation in the scaffold whilst the designed multilayer composite with gradient degradation characteristics in the space was used to match the new bone growth process better. The results of animal experiments showed that the use of low intensity pulsed ultrasound (LIPUS) combined with growth factors demonstrated excellent capabilities and advantages in both vascularization and new bone formation in bone tissue engineering. The degradation of the used scaffold materials could match new bone formation very well. The results also showed that only RGD-promoted cell adhesion was insufficient to satisfy the needs of new bone formation while growth factors and LIPUS stimulation were the key factors in new bone formation. © 2015 Wiley Periodicals, Inc.

Alzheimer's disease, cerebrovascular dysfunction and the benefits of exercise: from vessels to neurons.

PubMed

Lange-Asschenfeldt, Christian; Kojda, Georg

2008-06-01

Exercise training promotes extensive cardiovascular changes and adaptive mechanisms in both the peripheral and cerebral vasculature, such as improved organ blood flow, induction of antioxidant pathways, and enhanced angiogenesis and vascular regeneration. Clinical studies have demonstrated a reduction of morbidity and mortality from cardiovascular disease among exercising individuals. However, evidence from recent large clinical trials also suggests a substantial reduction of dementia risk - particularly regarding Alzheimer's disease (AD) - with regular exercise. Enhanced neurogenesis and improved synaptic plasticity have been implicated in this beneficial effect. However, recent research has revealed that vascular and specifically endothelial dysfunction is essentially involved in the disease process and profoundly aggravates underlying neurodegeneration. Moreover, vascular risk factors (VRFs) are probably determinants of incidence and course of AD. In this review, we emphasize the interconnection between AD and VRFs and the impact of cerebrovascular and endothelial dysfunction on AD pathophysiology. Furthermore, we describe the molecular mechanisms of the beneficial effects of exercise on the vasculature such as activation of the vascular nitric oxide (NO)/endothelial NO synthase (eNOS) pathway, upregulation of antioxidant enzymes, and angiogenesis. Finally, recent prospective clinical studies dealing with the effect of exercise on the risk of incident AD are briefly reviewed. We conclude that, next to upholding neuronal plasticity, regular exercise may counteract AD pathophysiology by building a vascular reserve.

Potential advantages of treatment of transplanted saphenous vein aorto-coronary artery bypass grafts with beta irradiation to prevent graft occlusion.

PubMed

Smith, R G

1997-01-01

Intimal proliferation or Neointimal hyperplasia (NIH) is a vascular lesion that often arises in arteries after balloon angioplasty or other vessel wall injuries. FIH is a vascular lesion that develops in autologous saphenous vein grafts (SVG) after transplantation into the aorto-coronary circulation or the peripheral vascular circulation. FIH shares elements of smooth muscle migration, proliferation and fibrous tissue deposition in common with nibrointimal proliferation (NIH). Either NIH of a coronary artery or FIH of a SVG obstruct the vascular lumen and result in myocardial dysfunction. Local radiotherapy has been used for several decades to reduce the post-operative recurrence of the fibrovascular proliferations of pterygia and keloids. Similarly, in animal and human experiments, endovascular radiotherapy has been shown to reduce arterial smooth muscle proliferation. Consideration of the similarities of vascular smooth muscle cell proliferation in NIH and FIH leads one to suggest that endovascular beta irradiation can reduce FIH as well as it reduces NIH. The goal of such treatment is to achieve a clinically significant decrease in the morbidity and mortality resulting from SVG occlusions. The potential for large reduction of the consequences of SVG occlusion, the very large number of patients at risk, and the simplicity of the proposed intervention encourages prompt scientific evaluation of this technique.

Real-Time Elastography Visualization and Histopathological Characterization of Rabbit Atherosclerotic Carotid Arteries.

PubMed

Wang, ZhenZhen; Liu, NaNa; Zhang, LiFeng; Li, XiaoYing; Han, XueSong; Peng, YanQing; Dang, MeiZheng; Sun, LiTao; Tian, JiaWei

2016-01-01

To evaluate the feasibility of non-invasive vascular real-time elastography imaging (RTE) in visualizing the composition of rabbit carotid atherosclerotic plaque as determined by histopathology, a rabbit model of accelerated carotid atherosclerosis was used. Thirty rabbits were randomly divided into two groups of 15 rabbits each. The first group was fed a cholesterol-rich diet and received balloon-induced injury the left common carotid artery endothelium, whereas the second group only received a cholesterol-rich diet. The rabbits were all examined in vivo with HITACHI non-invasive vascular real-time elastography (Hi-RTE) at baseline and 12 wk, and results from the elastography were compared with American Heart Association histologic classifications. Hi-RTE and the American Heart Association histologic classifications had good agreement, with weighted Cohen's kappa (95% confidence internal) of 0.785 (0.649-0.920). Strains of segmented plaques that were stained in different colors were statistically different (p < 0.0001). The sensitivity and specificity of elastograms for detecting a lipid core were 95.5% and 61.5%, respectively, and the area under the receiver operating characteristic curve was 0.789, with a 95% confidence interval of 0.679 to 0.876. This study is the first to indicate the feasibility of utilizing Hi-RTE in visualizing normal and atherosclerotic rabbit carotid arteries non-invasively. This affordable and reliable method can be widely applied in research of both animal and human peripheral artery atherosclerosis. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Early alterations in vascular contractility associated to changes in fatty acid composition and oxidative stress markers in perivascular adipose tissue.

PubMed

Rebolledo, Alejandro; Rebolledo, Oscar R; Marra, Carlos A; García, María E; Roldán Palomo, Ana R; Rimorini, Laura; Gagliardino, Juan J

2010-10-21

To test the early effect of fructose-induced changes in fatty acid composition and oxidative stress markers in perivascular adipose tissue (PVAT) upon vascular contractility. Adult male Wistar rats were fed a commercial diet without (CD) or with 10% fructose (FRD) in the drinking water for 3 weeks. We measured plasma metabolic parameters, lipid composition and oxidative stress markers in aortic PVAT. Vascular contractility was measured in aortic rings sequentially, stimulated with serotonin (5-HT) and high K+-induced depolarization using intact and thereafter PVAT-deprived rings. Comparable body weights were recorded in both groups. FRD rats had increased plasma triglyceride and fructosamine levels. Their PVAT had an increased saturated to mono- or poly-unsaturated fatty acid ratio, a significant decrease in total superoxide dismutase and glutathione peroxidase activities and in the total content of glutathione. Conversely, lipid peroxidation (TBARS), nitric oxide content, and gluthathione reductase activity were significantly higher, indicating an increase in oxidative stress. In aortic rings, removal of PVAT increased serotonin-induced contractions, but the effect was significantly lower in rings from FRD rats. This effect was no longer observed when the two contractions were performed in PVAT-deprived rings. PVAT did not affect the contractions triggered by high K+-induced depolarization either in CD or FRD rats. FRD induces multiple metabolic and endocrine systemic alterations which also alter PVAT and the vascular relaxant properties of this tissue. The changes in PVAT would affect its paracrine modulation of vascular function.

[Anatomo-functional changes in the prostate and seminal vesicles with aging].

PubMed

Mantovani, F; Mastromarino, G; Colombo, F; Canclini, L; Fenice, O

1993-10-01

The anatomo-functional modifications of the prostate and the seminal pathways during the genital apparatus aging, (prostatic hyperplasia and hypotrophy of the seminal pathways and testis), are caused by hormonal modifications (inconstant increase of the gonadotropins LH-FSH, decrease of the peripheric utilization of testosterone, alterations of the adrenal secretion), by anatomical involutions (degenerations of the glandular, stromal and vascular components).

Instructional Methods for Neuroscience in Nurse Anesthesia Graduate Programs: A Survey of Educational Programs

DTIC Science & Technology

1999-10-01

Sciences A. Anatomy, physiology and pathophysiology 1. Cardiovascular a. Arrhythmias b. Ischemic heart disease/angina c. Myocardial infarction d...Hypertension e. Congestive Heart Failure f. Shock Instructional Methods 66 g. Valvular Heart disease h. Cardiomyopathy i. Peripheral vascular disease j...Pulmonary artery pressure monitoring Instructional Methods 71 3. Precordial/esophageal stethoscope /Doppler 4. Respiratory monitoring a. Apnea monitor b

How to utilize Ca²⁺ signals to rejuvenate the repairative phenotype of senescent endothelial progenitor cells in elderly patients affected by cardiovascular diseases: a useful therapeutic support of surgical approach?

PubMed

Moccia, Francesco; Dragoni, Silvia; Cinelli, Mariapia; Montagnani, Stefania; Amato, Bruno; Rosti, Vittorio; Guerra, Germano; Tanzi, Franco

2013-01-01

Endothelial dysfunction or loss is the early event that leads to a host of severe cardiovascular diseases, such as atherosclerosis, hypertension, brain stroke, myocardial infarction, and peripheral artery disease. Ageing is regarded among the most detrimental risk factor for vascular endothelium and predisposes the subject to atheroscleorosis and inflammatory states even in absence of traditional comorbid conditions. Standard treatment to restore blood perfusion through stenotic arteries are surgical or endovascular revascularization. Unfortunately, ageing patients are not the most amenable candidates for such interventions, due to high operative risk or unfavourable vascular involvement. It has recently been suggested that the transplantation of autologous bone marrow-derived endothelial progenitor cells (EPCs) might constitute an alternative and viable therapeutic option for these individuals. Albeit pre-clinical studies demonstrated the feasibility of EPC-based therapy to recapitulate the diseased vasculature of young and healthy animals, clinical studies provided less impressive results in old ischemic human patients. One hurdle associated to this kind of approach is the senescence of autologous EPCs, which are less abundant in peripheral blood and display a reduced pro-angiogenic activity. Conversely, umbilical cord blood (UCB)-derived EPCs are more suitable for cellular therapeutics due to their higher frequency and sensitivity to growth factors, such as vascular endothelial growth factor (VEGF). An increase in intracellular Ca(2+) concentration is central to EPC activation by VEGF. We have recently demonstrated that the Ca(2+) signalling machinery driving the oscillatory Ca(2+) response to this important growth factor is different in UCB-derived EPCs as compared to their peripheral counterparts. In particular, we focussed on the so-called endothelial colony forming cells (ECFCs), which are the only EPC population belonging to the endothelial lineage and able to form capillary-like structures in vitro and stably integrate with host vasculature in vivo. The present review provides a brief description of how exploiting the Ca(2+) toolkit of juvenile EPCs to restore the repairative phenotype of senescent EPCs to enhance their regenerative outcome in therapeutic settings.

The Effect of Clinical Care Location on Clinical Outcomes After Peripheral Vascular Intervention in Medicare Beneficiaries.

PubMed

Turley, Ryan S; Mi, Xiaojuan; Qualls, Laura G; Vemulapalli, Sreekanth; Peterson, Eric D; Patel, Manesh R; Curtis, Lesley H; Jones, W Schuyler

2017-06-12

Modifications in reimbursement rates by Medicare in 2008 have led to peripheral vascular interventions (PVI) being performed more commonly in outpatient and office-based clinics. The objective of this study was to determine the effects of this shift in clinical care setting on clinical outcomes after PVI. Modifications in reimbursement have led to peripheral vascular intervention (PVI) being more commonly performed in outpatient hospital settings and office-based clinics. Using a 100% national sample of Medicare beneficiaries from 2010 to 2012, we examined 30-day and 1-year rates of all-cause mortality, major lower extremity amputation, repeat revascularization, and all-cause hospitalization by clinical care location of index PVI. A total of 218,858 Medicare beneficiaries underwent an index PVI between 2010 and 2012. Index PVIs performed in inpatient settings were associated with higher 1-year rates of all-cause mortality (23.6% vs. 10.4% and 11.7%; p < 0.001), major lower extremity amputation (10.1% vs. 3.7% and 3.5%; p < 0.001), and all-cause repeat hospitalization (63.3% vs. 48.5% and 48.0%; p < 0.001), but lower rates of repeat revascularization (25.1% vs. 26.9% vs. 38.6%; p < 0.001) when compared with outpatient hospital settings and office-based clinics, respectively. After adjustment for potential confounders, patients treated in office-based clinics remained more likely than patients in inpatient hospital settings to require repeat revascularization within 1 year across all specialties. There was also a statistically significant interaction effect between location of index revascularization and geographic region on the occurrence of all-cause hospitalization, repeat revascularization, and lower extremity amputation. Index PVI performed in office-based settings was associated with a higher hazard of repeat revascularization when compared with other settings. Differences in clinical outcomes across treatment settings and geographic regions suggest that inconsistent application of PVI may exist and highlights the need for studies to determine optimal delivery of PVI in clinical practice. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Influence of endurance and resistance exercise order on the postexercise hemodynamic responses in hypertensive women.

PubMed

Menêses, Annelise Lins; Forjaz, Cláudia Lúcia de Moraes; de Lima, Paulo Fernando Marinho; Batista, Rafael Marinho Falcão; Monteiro, Maria de Fátima; Ritti-Dias, Raphael Mendes

2015-03-01

The study aims to evaluate the effects of the order of endurance and resistance exercises on postexercise blood pressure (BP) and hemodynamics in hypertensive women. Nineteen hypertensive women underwent 3 sessions: control (50 minutes rest), endurance (50-60% of heart rate reserve) followed by resistance exercise (50% of 1 repetition maximum) (E + R), and resistance followed by endurance exercise (R + E). Before and 30 minutes after each session, BP, peripheral vascular resistance, cardiac output, stroke volume, and heart rate were measured. Postexercise increases in systolic (E + R: +1 ± 3 mm Hg and R + E: +3 ± 3 mm Hg), diastolic (E + R: +3 ± 1 mm Hg and R + E: +3 ± 2 mm Hg), and mean BP (E + R: +3 ± 1 mm Hg and R + E: +3 ± 2 mm Hg) were significantly lower after the exercise sessions compared with the control session (p ≤ 0.05). The exercise sessions abolished the increases in peripheral vascular resistance (E + R: +0.00 ± 0.04 mm Hg·min·L and R + E: +0.05 ± 0.05 mm Hg·min·L) and the decreases in cardiac output (E + R: +0.04 ± 0.28 L·min and R + E: -0.26 ± 0.28 L·min) observed after the control session (p ≤ 0.05). After the exercise sessions, stroke volume decreased (E + R: -14 ± 3 ml and R + E: -9 ± 4 ml) and heart rate increased (E + R: +5 ± 1 b·min and R + E: +4 ± 1 b·min) in comparison with the control session (p ≤ 0.05). For all the variables, there were no significant differences between the exercise sessions. Regardless of the order of endurance and resistance exercises, combined exercise sessions abolished increases in BP observed in a control condition due to a reduction in peripheral vascular resistance and increases in cardiac output. Thus, combined exercises should be prescribed to individuals with hypertension to control their BP, regardless of the order they are accomplished.

Diabetic foot syndrome: Immune-inflammatory features as possible cardiovascular markers in diabetes

PubMed Central

Tuttolomondo, Antonino; Maida, Carlo; Pinto, Antonio

2015-01-01

Diabetic foot ulcerations have been extensively reported as vascular complications of diabetes mellitus associated with a high degree of morbidity and mortality. Diabetic foot syndrome (DFS), as defined by the World Health Organization, is an “ulceration of the foot (distally from the ankle and including the ankle) associated with neuropathy and different grades of ischemia and infection”. Pathogenic events able to cause diabetic foot ulcers are multifactorial. Among the commonest causes of this pathogenic pathway it’s possible to consider peripheral neuropathy, foot deformity, abnormal foot pressures, abnormal joint mobility, trauma, peripheral artery disease. Several studies reported how diabetic patients show a higher mortality rate compared to patients without diabetes and in particular these studies under filled how cardiovascular mortality and morbidity is 2-4 times higher among patients affected by type 2 diabetes mellitus. This higher degree of cardiovascular morbidity has been explained as due to the observed higher prevalence of major cardiovascular risk factor, of asymptomatic findings of cardiovascular diseases, and of prevalence and incidence of cardiovascular and cerebrovascular events in diabetic patients with foot complications. In diabetes a fundamental pathogenic pathway of most of vascular complications has been reported as linked to a complex interplay of inflammatory, metabolic and procoagulant variables. These pathogenetic aspects have a direct interplay with an insulin resistance, subsequent obesity, diabetes, hypertension, prothrombotic state and blood lipid disorder. Involvement of inflammatory markers such as IL-6 plasma levels and resistin in diabetic subjects as reported by Tuttolomondo et al confirmed the pathogenetic issue of the a “adipo-vascular” axis that may contribute to cardiovascular risk in patients with type 2 diabetes. This “adipo-vascular axis” in patients with type 2 diabetes has been reported as characterized by lower plasma levels of adiponectin and higher plasma levels of interleukin-6 thus linking foot ulcers pathogenesis to microvascular and inflammatory events. The purpose of this review is to highlight the immune inflammatory features of DFS and its possible role as a marker of cardiovascular risk in diabetes patients and to focus the management of major complications related to diabetes such as infections and peripheral arteriopathy. PMID:25621212

Preventing collapsing of vascular scaffolds: The mechanical behavior of PLA/PCL composite structure prostheses during in vitro degradation.

PubMed

Li, Chaojing; Wang, Fujun; Chen, Peifeng; Zhang, Ze; Guidoin, Robert; Wang, Lu

2017-11-01

The success of blood conduit replacement with synthetic graft is highly dependent on the architecture, and mechanical properties of the graft, especially for biodegradable grafts serving as scaffolds for in-situ tissue engineering. Particularly, the property of the radial compression recovery represents a critical to keep the patency during biointegration. Bi-component composite vascular grafts (cVG) made of polylactic acid (PLA) fabric and polycaprolactone (PCL) were developed with superior mechanical properties. In this research, the compressive and tensile properties of the prototypes were characterized when they were subjected to accelerated degradation. In addition, the prepared cVG were analyzed by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and wide angle X-ray diffraction (WAXD) to illustrate the gradual loss of mechanical properties. The results demonstrated that the cVG retained the circular cross-section even through its tensile strength decreased during degradation. The cVG samples containing a high percentage of PLA fibers lost their tensile strength faster, while the samples with lower PLA percentage lost the compressive resistance strength more quickly. This unique fabric-based composite biodegradable vascular prosthesis with an outstanding radical compression recovery could be a good candidate for in-situ formation of tissue engineered vascular graft. Copyright © 2017 Elsevier Ltd. All rights reserved.

Vascularization of repaired limb bone defects using chitosan-β-tricalcium phosphate composite as a tissue engineering bone scaffold.

PubMed

Yang, Le; Wang, Qinghua; Peng, Lihua; Yue, Hong; Zhang, Zhendong

2015-08-01

Ensuring histocompatibility in the tissue engineering of bones is a complex issue. The aim of this study was to observe the feasibility of chitosan-β-tricalcium phosphate composite in repairing limb bone defects, and to evaluate the therapeutic effects on osteogenesis. Beagle mesenchymal stem cells (MSCs) were divided into an experimental group that was cultured with an injectable form of chitosan-β-tricalcium phosphate composite and a control group. The effect of the composite on bone tissue growth was evaluated by MTT assay. In addition, 12-month-old beagles were subjected to 15-mm femur defects and subsequently implanted with scaffolds to observe the effects on osteogenesis and vascularization. The dogs were subdivided into two groups of five animals: Group A, which was implanted with scaffold-MSC compounds, and Group B, which was implanted with scaffolds alone. The dogs were observed on the 2nd, 4th, 8th and 12th weeks post-implantation. Scanning electron microscopy analysis revealed that the composite was compatible with MSCs, with similar outcomes in the control and experimental groups. MTT analysis additionally showed that the MSCs in the experimental group grew in a similar manner to those in the control group. The composite did not significantly affect the MSC growth or proliferation. In combination with MSCs, the scaffold materials were effective in the promotion of osteogenesis and vascularization. In conclusion, the chitosan-β-tricalcium phosphate composite was compatible with the MSCs and did not affect cellular growth or proliferation, therefore proving to be an effective injectable composite for tissue engineered bone. Simultaneous implantation of stem cells with a carrier composite proved to function effectively in the repair of bone defects.

Real-time, label-free, intraoperative visualization of peripheral nerves and micro-vasculatures using multimodal optical imaging techniques

PubMed Central

Cha, Jaepyeong; Broch, Aline; Mudge, Scott; Kim, Kihoon; Namgoong, Jung-Man; Oh, Eugene; Kim, Peter

2018-01-01

Accurate, real-time identification and display of critical anatomic structures, such as the nerve and vasculature structures, are critical for reducing complications and improving surgical outcomes. Human vision is frequently limited in clearly distinguishing and contrasting these structures. We present a novel imaging system, which enables noninvasive visualization of critical anatomic structures during surgical dissection. Peripheral nerves are visualized by a snapshot polarimetry that calculates the anisotropic optical properties. Vascular structures, both venous and arterial, are identified and monitored in real-time using a near-infrared laser-speckle-contrast imaging. We evaluate the system by performing in vivo animal studies with qualitative comparison by contrast-agent-aided fluorescence imaging. PMID:29541506

Conditions Presenting with Symptoms of Peripheral Arterial Disease

PubMed Central

Sharma, Aditya M.; Norton, Patrick T.; Zhu, Daisy

2014-01-01

Peripheral artery disease (PAD) is estimated to affect more than 20% of people older than 65 years. The vast majority of patients with symptoms suggestive of PAD have atherosclerosis often associated with conventional vascular risk factors such as smoking, diabetes, dyslipidemia, and inflammation. A minority of people presenting with symptoms suggesting PAD have an alternative etiology. These groups of disorders are often underdiagnosed, and if diagnosed correctly the diagnosis may be delayed. Understanding these pathologies well is important, as they can be very debilitating and optimal treatment may vary significantly. Inappropriate treatment of these disorders can lead to worsening morbidity and mortality. This article discusses the underlying causes of nonatherosclerotic PAD, including the diagnosis and treatment of these disorders. PMID:25435652

Protective effect of Tribulus terrestris linn on liver and kidney in cadmium intoxicated rats.

PubMed

Lakshmi, G Dhana; Kumar, P Ravi; Bharavi, K; Annapurna, P; Rajendar, B; Patel, Pankaj T; Kumar, C S V Satish; Rao, G S

2012-02-01

Administration of cadmium (Cd) significantly increased the peroxidation markers such as malondialdehyde and protein carbonyls along with significant decrease in antioxidant markers such as super oxide dismutase and reduced glutathione in liver and kidney tissues. Cadmium also caused a significant alteration in hepatic and renal functional markers in serum viz. total protein, albumin, alanine transaminase, blood urea nitrogen and creatinine. Prominent pathological changes observed in liver were severe vascular and sinusoidal congestion with diffuse degenerative changes and mononuclear infiltration into peripheral areas, while the kidney showed vascular and glomerular congestion, cloudy swelling of tubular epithelium. Coadministration of ethonolic extract of T. terrestris or vitamin E along with Cd significantly reversed the Cd induced changes along with significant reduction in Cd load.

Emerging roles of GPER in diabetes and atherosclerosis.

PubMed

Barton, Matthias; Prossnitz, Eric R

2015-04-01

The G protein-coupled estrogen receptor (GPER) is a 7-transmembrane receptor implicated in rapid estrogen signaling. Originally cloned from vascular endothelial cells, GPER plays a central role in the regulation of vascular tone and cell growth as well as lipid and glucose homeostasis. This review highlights our knowledge of the physiological and pathophysiological functions of GPER in the pancreas, peripheral and immune tissues, and the arterial vasculature. Recent findings on its roles in obesity, diabetes, and atherosclerosis, including GPER-dependent regulation of lipid metabolism and inflammation, are presented. The therapeutic potential of targeting GPER-dependent pathways in chronic diseases such as coronary artery disease and diabetes and in the context of menopause is also discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

[THE STATE OF HEPATIC AND SPLANCHNIC BLOOD FLOW IN VARIOUS TYPES OF COMPLICATED PANCREATIC PSEUDOCYSTS].

PubMed

Kryvoruchko, I A; Goncharova, N M; Andreyeshchev, S A; Yavorska, T P

2015-05-01

Investigations were conducted in 37 patients, suffering complicated pancreatic pseudocysts. In accordance to data of ultrasound Doppler flowmetry for the blood flow along portal vein, a. hepatis communis, a. mesenterica superior in complicated pancreatic pseudocysts compensatory--adaptive reactions on level of hepatic--spanchnic blood flow are directed towards restriction of the blood inflow through the portal vein system. This is accompanied by the common peripheral vascular resistence raising in basin of a. mesenterica superior, which have depended upon the patients' state severity, caused by reduction of the volume blood flow in a certan vascular collector. The oxygen debt of the liver in these patients is compensated by the volume blood flow enhancement along a. hepatis communis.

Biological Strategies to Enhance Healing of the Avascular Area of the Meniscus

PubMed Central

Longo, Umile Giuseppe; Campi, Stefano; Romeo, Giovanni; Spiezia, Filippo; Maffulli, Nicola; Denaro, Vincenzo

2012-01-01

Meniscal injuries in the vascularized peripheral part of the meniscus have a better healing potential than tears in the central avascular zone because meniscal healing principally depends on its vascular supply. Several biological strategies have been proposed to enhance healing of the avascular area of the meniscus: abrasion therapy, fibrin clot, organ culture, cell therapy, and applications of growth factors. However, data are too heterogeneous to achieve definitive conclusions on the use of these techniques for routine management of meniscal lesions. Although most preclinical and clinical studies are very promising, they are still at an experimental stage. More prospective randomised controlled trials are needed to compare the different techniques for clinical results, applicability, and cost-effectiveness. PMID:22220179

A Network-Biology Informed Computational Drug Repositioning Strategy to Target Disease Risk Trajectories and Comorbidities of Peripheral Artery Disease.

PubMed

Shameer, Khader; Dow, Garrett; Glicksberg, Benjamin S; Johnson, Kipp W; Ze, Yi; Tomlinson, Max S; Readhead, Ben; Dudley, Joel T; Kullo, Iftikhar J

2018-01-01

Currently, drug discovery approaches focus on the design of therapies that alleviate an index symptom by reengineering the underlying biological mechanism in agonistic or antagonistic fashion. For example, medicines are routinely developed to target an essential gene that drives the disease mechanism. Therapeutic overloading where patients get multiple medications to reduce the primary and secondary side effect burden is standard practice. This single-symptom based approach may not be scalable, as we understand that diseases are more connected than random and molecular interactions drive disease comorbidities. In this work, we present a proof-of-concept drug discovery strategy by combining network biology, disease comorbidity estimates, and computational drug repositioning, by targeting the risk factors and comorbidities of peripheral artery disease, a vascular disease associated with high morbidity and mortality. Individualized risk estimation and recommending disease sequelae based therapies may help to lower the mortality and morbidity of peripheral artery disease.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wexler, J.P.; Davis, L.; Mancini, D.

Cardioactive drugs may effect both the central and peripheral circulatory systems. The effects on the central and peripheral circulatory systems of chronic Captorpril therapy in 7 pts with severe congestive heart failure (CHF) were evaluated simultaneously. Skeletal muscle blood flow (SMBF) determined using 133-Xe washout and a Cd/Te detector, oxygen consumption (VO/sub 2/), and radial artery and femoral vein O/sub 2/ concentration difference (A-V) were determined at rest and peak upright bicycle exercise before (BT) and after (AT) 6-12 weeks of Captopril therapy. In CI pts there was a significant increase in VO/sub 2/ and SMBF AT vs BT. Inmore » contrast, in CNC pts there was no change in VO/sub 2/ and a significant decrease in SMBF AT vs BT. In pts with severe CHF who are CI, there is an apparent fall in peripheral vascular resistance (PVR). In contrast, in CNC pts there is an increase in PVR. This study demonstrates that SMBF determines using 133-Xe is an important method for determining the effects of cardioactive drugs.« less

Topical Nitroglycerine for Neonatal Arterial Associated Peripheral Ischemia following Cannulation: A Case Report and Comprehensive Literature Review

PubMed Central

Mosalli, Rafat; Elbaz, Mohamed; Paes, Bosco

2013-01-01

Arterial cannulation in neonates is usually performed for frequent blood pressure monitoring and blood sampling. The procedure, while easily executed by skilled neonatal staff, can be associated with serious complications such as vasospasm, thrombosis, embolism, hematoma, infection, peripheral nerve damage, ischemia, and tissue necrosis. Several treatment options are available to reverse vascular induced ischemia and tissue damage. Applied interventions depend on the extent of tissue involvement and whether the condition is progressive and deemed life threatening. Standard, noninvasive measures include immediate catheter removal, limb elevation, and warming the contralateral extremity. Topical vasodilators, anticoagulation, thrombolysis, and surgery are considered secondary therapeutic strategies. A comprehensive literature search indicates that topical nitroglycerin has been utilized for the treatment of tissue ischemia in three preterms with umbilical arterial catheters and four with peripheral arterial lines. We report the first successful use of nitroglycerine ointment in a critically ill preterm infant with ischemic hand changes after brachial artery cannulation. PMID:24251058

Percutaneous treatment of peripheral vascular disease: The role of diabetes and inflammation

PubMed Central

Nguyen, Louis L.

2010-01-01

Peripheral arterial disease (PAD) is a growing health problem for many Americans and often occurs along with other cardiovascular risk factors, including diabetes mellitus (DM), low-grade inflammation, hypertension, and lipid disorders. Intermittent claudication (IC), an early manifestation of PAD, commonly leads to reduced quality of life for patients who are limited in their ambulation. While recent wide adoption of percutaneous peripheral interventional (PPI) techniques has increased the number patients being aggressively treated for IC, the overall effectiveness of PPI for the treatment of IC is not well known, especially for DM patients who have both hemodynamic and functional obstacles to treatment success. This review is designed to illustrate how treatment outcomes for IC can be measured by different modalities and how diabetes and inflammation can influence those outcomes. In the setting of greater concern for health care resources and clinical accountability, better understanding of treatment outcomes and efficacy will help us manage these complex challenges. PMID:17544036

A Network-Biology Informed Computational Drug Repositioning Strategy to Target Disease Risk Trajectories and Comorbidities of Peripheral Artery Disease

PubMed Central

Shameer, Khader; Dow, Garrett; Glicksberg, Benjamin S.; Johnson, Kipp W.; Ze, Yi; Tomlinson, Max S.; Readhead, Ben; Dudley, Joel T.; Kullo, Iftikhar J.

2018-01-01

Currently, drug discovery approaches focus on the design of therapies that alleviate an index symptom by reengineering the underlying biological mechanism in agonistic or antagonistic fashion. For example, medicines are routinely developed to target an essential gene that drives the disease mechanism. Therapeutic overloading where patients get multiple medications to reduce the primary and secondary side effect burden is standard practice. This single-symptom based approach may not be scalable, as we understand that diseases are more connected than random and molecular interactions drive disease comorbidities. In this work, we present a proof-of-concept drug discovery strategy by combining network biology, disease comorbidity estimates, and computational drug repositioning, by targeting the risk factors and comorbidities of peripheral artery disease, a vascular disease associated with high morbidity and mortality. Individualized risk estimation and recommending disease sequelae based therapies may help to lower the mortality and morbidity of peripheral artery disease. PMID:29888052

[Assertiveness and peripheral intravenous catheters dwell time with ultrasonography-guided insertion in children and adolescents].

PubMed

Avelar, Ariane Ferreira Machado; Peterlini, Maria Angélica Sorgini; da Pedreira, Mavilde Luz Gonçalves

2013-06-01

Randomized controlled trial which aimed to verify whether the use of vascular ultrasound (VUS) increases assertiveness in the use of peripheral venous catheter in children, and the catheter dwell time, when compared to traditional puncture. Data were collected after approval of theethical merit. Children and adolescents undergoing VUS-guided peripheral intravenous (GVUS) or puncture guided by clinical assessment of the venous conditions(CG) were included in the study. Significance level was set at p< or =0.05. The sample was composed of 382 punctures, 188 (49.2%) in VUS Gand 194 (50.8%) in CG, performed in 335 children. Assertiveness was found in 73 (71.6%) GVUS catheters and in 84(71.8%) of the CG (p=0.970), and catheter dwell time presented a median of less than one day in both groups (p=0.121), showing nostatistically significant difference. VUS did not significantly influence the results of the dependent variables investigated. ClinicalTrials.govNCT00930254.

Endocannabinoids in Liver Disease

PubMed Central

Tam, Joseph; Liu, Jie; Mukhopadhyay, Bani; Cinar, Resat; Godlewski, Grzegorz; Kunos, George

2010-01-01

Endocannabinoids are lipid mediators of the same cannabinoid (CB) receptors that mediate the effects of marijuana. The endocannabinoid system (ECS) consists of CB receptors, endocannabinoids, and the enzymes involved in their biosynthesis and degradation, and is present both in brain and peripheral tissues, including the liver. The hepatic ECS is activated in various liver diseases, which contributes to the underlying pathologies. In cirrhosis of various etiologies, activation of vascular and cardiac CB1 receptors by macrophage- and platelet-derived endocannabinoids contribute to the vasodilated state and cardiomyopathy, which can be reversed by CB1 blockade. In mouse models of liver fibrosis, activation of CB1 receptors on hepatic stellate cells is fibrogenic, and CB1 blockade slows the progression of fibrosis. Fatty liver induced by high-fat diets or chronic alcohol feeding depend on activation of peripheral, including hepatic CB1 receptors, which also contribute to insulin resistance and dyslipidemias. Although the documented therapeutic potential of CB1 blockade is limited by neuropsychiatric side effects, these may be mitigated by using novel, peripherally restricted CB1 antagonists. PMID:21254182

Perfusion-decellularization of human ear grafts enables ECM-based scaffolds for auricular vascularized composite tissue engineering.

PubMed

Duisit, Jérôme; Amiel, Hadrien; Wüthrich, Tsering; Taddeo, Adriano; Dedriche, Adeline; Destoop, Vincent; Pardoen, Thomas; Bouzin, Caroline; Joris, Virginie; Magee, Derek; Vögelin, Esther; Harriman, David; Dessy, Chantal; Orlando, Giuseppe; Behets, Catherine; Rieben, Robert; Gianello, Pierre; Lengelé, Benoît

2018-06-01

Human ear reconstruction is recognized as the emblematic enterprise in tissue engineering. Up to now, it has failed to reach human applications requiring appropriate tissue complexity along with an accessible vascular tree. We hereby propose a new method to process human auricles in order to provide a poorly immunogenic, complex and vascularized ear graft scaffold. 12 human ears with their vascular pedicles were procured. Perfusion-decellularization was applied using a SDS/polar solvent protocol. Cell and antigen removal was examined by histology and DNA was quantified. Preservation of the extracellular matrix (ECM) was assessed by conventional and 3D-histology, proteins and cytokines quantifications. Biocompatibility was assessed by implantation in rats for up to 60 days. Adipose-derived stem cells seeding was conducted on scaffold samples and with human aortic endothelial cells whole graft seeding in a perfusion-bioreactor. Histology confirmed cell and antigen clearance. DNA reduction was 97.3%. ECM structure and composition were preserved. Implanted scaffolds were tolerated in vivo, with acceptable inflammation, remodeling, and anti-donor antibody formation. Seeding experiments demonstrated cell engraftment and viability. Vascularized and complex auricular scaffolds can be obtained from human source to provide a platform for further functional auricular tissue engineered constructs, hence providing an ideal road to the vascularized composite tissue engineering approach. The ear is emblematic in the biofabrication of tissues and organs. Current regenerative medicine strategies, with matrix from donor tissues or 3D-printed, didn't reach any application for reconstruction, because critically missing a vascular tree for perfusion and transplantation. We previously described the production of vascularized and cell-compatible scaffolds, from porcine ear grafts. In this study, we ---- applied findings directly to human auricles harvested from postmortem donors, providing a perfusable matrix that retains the ear's original complexity and hosts new viable cells after seeding. This approach unlocks the ability to achieve an auricular tissue engineering approach, associated with possible clinical translation. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

The distribution and ultrastructure of the forming blood capillaries and the effect of apoptosis on vascularization in mouse embryonic molar mesenchyme.

PubMed

Yuan, Guohua; Zhang, Li; Yang, Guobin; Yang, Jingwen; Wan, Chunyan; Zhang, Lu; Song, Guangtai; Chen, Shuo; Chen, Zhi

2014-04-01

Vascularization is essential for organ and tissue development. Teeth develop through interactions between epithelium and mesenchyme. The developing capillaries in the enamel organ, the dental epithelial structure, occur simultaneously by mechanisms of vasculogenesis and angiogenesis at the onset of dentinogenesis. The vascular neoformation in the dental mesenchyme has been reported to start from the cap stage. However, the mechanisms of vascularization in the dental mesenchyme remain unknown. In the hope of understanding the mechanisms of the formation of dental mesenchymal vasculature, mouse lower molar germs from embryonic day (E) 13.5 to E16.5 were processed for immunostaining of CD31 and CD34, terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) and transmission electron microscopy (TEM). In addition, the role of apoptosis for the vascularization in dental mesenchyme was examined by in vitro culture of E14.0 lower molars in the presence of the apoptosis inhibitor (z-VAD-fmk) and a subsequent subrenal culture. Our results showed that CD31- and CD34-positive cells progressively entered the central part of the dental papilla from the peridental mesenchyme. For TEM, angioblasts, young capillaries with thick endothelium and endothelial cells containing vacuoles were observed in peripheral dental mesenchyme, suggesting vasculogenesis was taking place. The presence of lateral sprouting, cytoplasmic filopodia and transluminal bridges in the dental papilla suggested angiogenesis was also occurring. Inhibition of apoptosis delayed the angiogenic vascularization of the dental papilla. Therefore, these data demonstrated that molar mesenchyme is progressively vascularized by mechanisms of both vasculogenesis and angiogenesis and apoptosis partially contributes to the vascularization of the dental papilla.

NLRP3 Inflammasome Mediates Aldosterone-Induced Vascular Damage.

PubMed

Bruder-Nascimento, Thiago; Ferreira, Nathanne S; Zanotto, Camila Z; Ramalho, Fernanda; Pequeno, Isabela O; Olivon, Vania C; Neves, Karla B; Alves-Lopes, Rheure; Campos, Eduardo; Silva, Carlos Alberto A; Fazan, Rubens; Carlos, Daniela; Mestriner, Fabiola L; Prado, Douglas; Pereira, Felipe V; Braga, Tarcio; Luiz, Joao Paulo M; Cau, Stefany B; Elias, Paula C; Moreira, Ayrton C; Câmara, Niels O; Zamboni, Dario S; Alves-Filho, Jose Carlos; Tostes, Rita C

2016-12-06

Inflammation is a key feature of aldosterone-induced vascular damage and dysfunction, but molecular mechanisms by which aldosterone triggers inflammation remain unclear. The NLRP3 inflammasome is a pivotal immune sensor that recognizes endogenous danger signals triggering sterile inflammation. We analyzed vascular function and inflammatory profile of wild-type (WT), NLRP3 knockout (NLRP3 -/- ), caspase-1 knockout (Casp-1 -/- ), and interleukin-1 receptor knockout (IL-1R -/- ) mice treated with vehicle or aldosterone (600 µg·kg -1 ·d -1 for 14 days through osmotic mini-pump) while receiving 1% saline to drink. Here, we show that NLRP3 inflammasome plays a central role in aldosterone-induced vascular dysfunction. Long-term infusion of aldosterone in mice resulted in elevation of plasma interleukin-1β levels and vascular abnormalities. Mice lacking the IL-1R or the inflammasome components NLRP3 and caspase-1 were protected from aldosterone-induced vascular damage. In vitro, aldosterone stimulated NLRP3-dependent interleukin-1β secretion by bone marrow-derived macrophages by activating nuclear factor-κB signaling and reactive oxygen species generation. Moreover, chimeric mice reconstituted with NLRP3-deficient hematopoietic cells showed that NLRP3 in immune cells mediates aldosterone-induced vascular damage. In addition, aldosterone increased the expression of NLRP3, active caspase-1, and mature interleukin-1β in human peripheral blood mononuclear cells. Hypertensive patients with hyperaldosteronism or normal levels of aldosterone exhibited increased activity of NLRP3 inflammasome, suggesting that the effect of hyperaldosteronism on the inflammasome may be mediated through high blood pressure. Together, these data demonstrate that NLRP3 inflammasome, through activation of IL-1R, is critically involved in the deleterious vascular effects of aldosterone, placing NLRP3 as a potential target for therapeutic interventions in conditions with high aldosterone levels. © 2016 American Heart Association, Inc.

Vascular plant-mediated controls on atmospheric carbon assimilation and peat carbon decomposition under climate change.

PubMed

Gavazov, Konstantin; Albrecht, Remy; Buttler, Alexandre; Dorrepaal, Ellen; Garnett, Mark H; Gogo, Sebastien; Hagedorn, Frank; Mills, Robert T E; Robroek, Bjorn J M; Bragazza, Luca

2018-03-23

Climate change can alter peatland plant community composition by promoting the growth of vascular plants. How such vegetation change affects peatland carbon dynamics remains, however, unclear. In order to assess the effect of vegetation change on carbon uptake and release, we performed a vascular plant-removal experiment in two Sphagnum-dominated peatlands that represent contrasting stages of natural vegetation succession along a climatic gradient. Periodic measurements of net ecosystem CO 2 exchange revealed that vascular plants play a crucial role in assuring the potential for net carbon uptake, particularly with a warmer climate. The presence of vascular plants, however, also increased ecosystem respiration, and by using the seasonal variation of respired CO 2 radiocarbon (bomb- 14 C) signature we demonstrate an enhanced heterotrophic decomposition of peat carbon due to rhizosphere priming. The observed rhizosphere priming of peat carbon decomposition was matched by more advanced humification of dissolved organic matter, which remained apparent beyond the plant growing season. Our results underline the relevance of rhizosphere priming in peatlands, especially when assessing the future carbon sink function of peatlands undergoing a shift in vegetation community composition in association with climate change. © 2018 John Wiley & Sons Ltd.

Role of Glyceraldehyde-Derived AGEs and Mitochondria in Superoxide Production in Femoral Artery of OLETF Rat and Effects of Pravastatin.

PubMed

Hori, Eisei; Kikuchi, Chigusa; Nagami, Chie; Kajikuri, Junko; Itoh, Takeo; Takeuchi, Masayoshi; Matsunaga, Tamihide

2017-11-01

A complication of diabetes mellitus is the over-production of vascular superoxides, which contribute to the development of arteriosclerosis and peripheral arterial disease (PAD). Hyperglycemia induces the formation and accumulation of advanced glycation end-products (AGEs), which in turn stimulate vascular superoxide production. The mechanism underlying AGE-mediated vascular superoxide production remains to be clarified in lower limb complications associated with diabetes. In the present study, we investigated the role of AGEs and the mitochondrial respiratory complex in superoxide production in femoral arteries using the type 2 diabetes model Otsuka Long-Evans Tokushima Fatty (OLETF) rats [vs. non-diabetic Long-Evans Tokushima Otsuka (LETO) rats]. The effects of in vivo administration of pravastatin on superoxide production in femoral arteries were also examined. Using chemiluminescent assays, luminescence microscopy, and competitive enzyme-linked immunosorbent assay (ELISA), we determined that vascular superoxide production and serum glyceraldehyde-derived AGEs (Glycer-AGEs) increased in OLETF rats. Pravastatin inhibited these responses without changing serum total cholesterol concentrations. The mitochondrial complex II inhibitor thenoyltrifluoroacetone (TTFA) also inhibited vascular superoxide production. Application of Glycer-AGEs in situ increased superoxide production in the vascular wall of femoral arteries from pravastatin-treated OLETF rats, which was then inhibited by TTFA. These results suggest that hyperglycemia increases serum Glycer-AGEs, which subsequently induce superoxide production in the femoral artery of OLETF rats in a mitochondrial complex II-dependent manner. Collectively, our results have partially elucidated the pathological mechanisms leading to diabetes-related PAD, and indicate dual beneficial actions of pravastatin for the prevention of oxidative damage to the vascular wall.

Vascular dysfunction in preeclampsia.

PubMed

Brennan, Lesley J; Morton, Jude S; Davidge, Sandra T

2014-01-01

Preeclampsia is a complex disorder which affects an estimated 5% of all pregnancies worldwide. It is diagnosed by hypertension in the presence of proteinuria after the 20th week of pregnancy and is a prominent cause of maternal morbidity and mortality. As delivery is currently the only known treatment, preeclampsia is also a leading cause of preterm delivery. Preeclampsia is associated with maternal vascular dysfunction, leading to serious cardiovascular risk both during and following pregnancy. Endothelial dysfunction, resulting in increased peripheral resistance, is an integral part of the maternal syndrome. While the cause of preeclampsia remains unknown, placental ischemia resulting from aberrant placentation is a fundamental characteristic of the disorder. Poor placentation is believed to stimulate the release of a number of factors including pro- and antiangiogenic factors and inflammatory activators into the maternal systemic circulation. These factors are critical mediators of vascular function and impact the endothelium in distinctive ways, including enhanced endothelial oxidative stress. The mechanisms of action and the consequences on the maternal vasculature will be discussed in this review. © 2013 John Wiley & Sons Ltd.

Vascular Access Tracking System: a Web-Based Clinical Tracking Tool for Identifying Catheter Related Blood Stream Infections in Interventional Radiology Placed Central Venous Catheters.

PubMed

Morrison, James; Kaufman, John

2016-12-01

Vascular access is invaluable in the treatment of hospitalized patients. Central venous catheters provide a durable and long-term solution while saving patients from repeated needle sticks for peripheral IVs and blood draws. The initial catheter placement procedure and long-term catheter usage place patients at risk for infection. The goal of this project was to develop a system to track and evaluate central line-associated blood stream infections related to interventional radiology placement of central venous catheters. A customized web-based clinical database was developed via open-source tools to provide a dashboard for data mining and analysis of the catheter placement and infection information. Preliminary results were gathered over a 4-month period confirming the utility of the system. The tools and methodology employed to develop the vascular access tracking system could be easily tailored to other clinical scenarios to assist in quality control and improvement programs.

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

PubMed

Recio-Rodriguez, Jose I; Gomez-Marcos, Manuel A; Patino Alonso, Maria C; Martin-Cantera, Carlos; Ibañez-Jalon, Elisa; Melguizo-Bejar, Amor; Garcia-Ortiz, Luis

2013-12-01

The present study analyses the relation between smoking status and the parameters used to assess vascular structure and function. This cross-sectional, multi-centre study involved a random sample of 1553 participants from the EVIDENT study. 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. 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. Among the parameters of vascular structure and function analysed, only the IMT shows association with the smoking status, after adjusting for confounders.

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

The Promise of Cell Based Therapies for Diabetic Complications: challenges and solutions

PubMed Central

Jarajapu, Yagna P.R.; Grant, Maria B.

2013-01-01

The discovery of endothelial progenitor cells (EPCs) in human peripheral blood advanced the field of cell-based therapeutics for many pathological conditions. Despite the lack of agreement about the existence and characteristics of EPCs, autologous EPC populations represent a novel treatment option for complications requiring therapeutic revascularization and vascular repair. Patients with diabetic complications represent a population of patients that may benefit from cellular therapy yet their broadly dysfunctional cells may limit the feasibility of this approach. Diabetic EPCs have decreased migratory prowess and reduced proliferative capacity and an altered cytokine/ growth factor secretory profile that can accelerates deleterious repair mechanisms rather than support proper vascular repair. Furthermore, the diabetic environment poses additional challenges for the autologous transplantation of cells. The present review is focused on correcting diabetic EPC dysfunction and the challenges involved in the application of cell-based therapies for treatment of diabetic vascular complications. In addition, ex vivo and in vivo functional manipulation(s) of EPCs to overcome these hurdles are discussed. PMID:20299675

Cystathionine γ-Lyase-Produced Hydrogen Sulfide Controls Endothelial NO Bioavailability and Blood Pressure.

PubMed

Szijártó, István András; Markó, Lajos; Filipovic, Milos R; Miljkovic, Jan Lj; Tabeling, Christoph; Tsvetkov, Dmitry; Wang, Ning; Rabelo, Luiza A; Witzenrath, Martin; Diedrich, André; Tank, Jens; Akahoshi, Noriyuki; Kamata, Shotaro; Ishii, Isao; Gollasch, Maik

2018-06-01

Hydrogen sulfide (H 2 S) and NO are important gasotransmitters, but how endogenous H 2 S affects the circulatory system has remained incompletely understood. Here, we show that CTH or CSE (cystathionine γ-lyase)-produced H 2 S scavenges vascular NO and controls its endogenous levels in peripheral arteries, which contribute to blood pressure regulation. Furthermore, eNOS (endothelial NO synthase) and phospho-eNOS protein levels were unaffected, but levels of nitroxyl were low in CTH-deficient arteries, demonstrating reduced direct chemical interaction between H 2 S and NO. Pretreatment of arterial rings from CTH-deficient mice with exogenous H 2 S donor rescued the endothelial vasorelaxant response and decreased tissue NO levels. Our discovery that CTH-produced H 2 S inhibits endogenous endothelial NO bioavailability and vascular tone is novel and fundamentally important for understanding how regulation of vascular tone is tailored for endogenous H 2 S to contribute to systemic blood pressure function. © 2018 American Heart Association, Inc.

Preliminary application of a novel algorithm to monitor changes in pre-flight total peripheral resistance for prediction of post-flight orthostatic intolerance in astronauts

NASA Astrophysics Data System (ADS)

Arai, Tatsuya; Lee, Kichang; Stenger, Michael B.; Platts, Steven H.; Meck, Janice V.; Cohen, Richard J.

2011-04-01

Orthostatic intolerance (OI) is a significant challenge for astronauts after long-duration spaceflight. Depending on flight duration, 20-80% of astronauts suffer from post-flight OI, which is associated with reduced vascular resistance. This paper introduces a novel algorithm for continuously monitoring changes in total peripheral resistance (TPR) by processing the peripheral arterial blood pressure (ABP). To validate, we applied our novel mathematical algorithm to the pre-flight ABP data previously recorded from twelve astronauts ten days before launch. The TPR changes were calculated by our algorithm and compared with the TPR value estimated using cardiac output/heart rate before and after phenylephrine administration. The astronauts in the post-flight presyncopal group had lower pre-flight TPR changes (1.66 times) than those in the non-presyncopal group (2.15 times). The trend in TPR changes calculated with our algorithm agreed with the TPR trend calculated using measured cardiac output in the previous study. Further data collection and algorithm refinement are needed for pre-flight detection of OI and monitoring of continuous TPR by analysis of peripheral arterial blood pressure.

Registry Assessment of Peripheral Interventional Devices (RAPID)　- Registry Assessment of Peripheral Interventional Devices Core Data Elements.

PubMed

Jones, W Schuyler; Krucoff, Mitchell W; Morales, Pablo; Wilgus, Rebecca W; Heath, Anne H; Williams, Mary F; Tcheng, James E; Marinac-Dabic, J Danica; Malone, Misti L; Reed, Terrie L; Fukaya, Rie; Lookstein, Robert; Handa, Nobuhiro; Aronow, Herbert D; Bertges, Daniel J; Jaff, Michael R; Tsai, Thomas T; Smale, Joshua A; Zaugg, Margo J; Thatcher, Robert J; Cronenwett, Jack L; Nc, Durham; Md, Silver Spring; Japan, Tokyo; Ny, New York; Ri, Providence; Vt, Burlington; Mass, Newton; Colo, Denver; Ariz, Tempe; Calif, Santa Clara; Minn, Minneapolis; Nh, Lebanon

2018-01-25

The current state of evaluating patients with peripheral artery disease and more specifically of evaluating medical devices used for peripheral vascular intervention (PVI) remains challenging because of the heterogeneity of the disease process, the multiple physician specialties that perform PVI, the multitude of devices available to treat peripheral artery disease, and the lack of consensus about the best treatment approaches. Because PVI core data elements are not standardized across clinical care, clinical trials, and registries, aggregation of data across different data sources and physician specialties is currently not feasible.Methods and Results:Under the auspices of the U.S. Food and Drug Administration's Medical Device Epidemiology Network initiative-and its PASSION (Predictable and Sustainable Implementation of the National Registries) program, in conjunction with other efforts to align clinical data standards-the Registry Assessment of Peripheral Interventional Devices (RAPID) workgroup was convened. RAPID is a collaborative, multidisciplinary effort to develop a consensus lexicon and to promote interoperability across clinical care, clinical trials, and national and international registries of PVI. The current manuscript presents the initial work from RAPID to standardize clinical data elements and definitions, to establish a framework within electronic health records and health information technology procedural reporting systems, and to implement an informatics-based approach to promote the conduct of pragmatic clinical trials and registry efforts in PVI. Ultimately, we hope this work will facilitate and improve device evaluation and surveillance for patients, clinicians, health outcomes researchers, industry, policymakers, and regulators.

Position of peripheral venous cannulae and the incidence of thrombophlebitis: an observational study.

PubMed

Cicolini, Giancarlo; Bonghi, Antonia Pollidoro; Di Labio, Luisa; Di Mascio, Rocco

2009-06-01

This paper is a report of a study conducted to investigate the most suitable location of peripheral venous cannulae to reduce the incidence of thrombophlebitis. Peripheral intravenous cannulae are used for vascular access, but the site of insertion and size of the cannula could expose patients to local and systemic infectious complications. Small cannula size is an important factor in reducing the incidence of thrombophlebitis, but cannula location has not yet been studied. Evidence-based knowledge on how to prevent these complications is needed. An observational survey carried out was carried out in 2007 with 427 patients in one Italian hospital. A structured observation protocol was used to survey the frequency of thrombophlebitis and the relationship of location and size of peripheral intravenous cannulae. The variables evaluated were age, gender, cannula size and site of cannula location. Chi-square or Student t tests were used, and the adjusted odds ratios and relative 95% confidence intervals are reported. The frequency of peripheral intravenous cannulae thrombophlebitis was higher in females (OR:1.91;CI:1.20-3.03;P < 0.006). The highest incidence was found in patients with cannulae inserted in the dorsal side of the hand veins compared to those with cannulae inserted in cubital fossa veins (OR:3.33;CI:1.37-8.07; P < 0.001). The use of cubital fossa veins rather than forearm and hand veins should be encouraged to reduce the risk of thrombophlebitis in patients with peripheral intravenous cannulae.

Impact of CT perfusion imaging on the assessment of peripheral chronic pulmonary thromboembolism: clinical experience in 62 patients.

PubMed

Le Faivre, Julien; Duhamel, Alain; Khung, Suonita; Faivre, Jean-Baptiste; Lamblin, Nicolas; Remy, Jacques; Remy-Jardin, Martine

2016-11-01

To evaluate the impact of CT perfusion imaging on the detection of peripheral chronic pulmonary embolisms (CPE). 62 patients underwent a dual-energy chest CT angiographic examination with (a) reconstruction of diagnostic and perfusion images; (b) enabling depiction of vascular features of peripheral CPE on diagnostic images and perfusion defects (20 segments/patient; total: 1240 segments examined). The interpretation of diagnostic images was of two types: (a) standard (i.e., based on cross-sectional images alone) or (b) detailed (i.e., based on cross-sectional images and MIPs). The segment-based analysis showed (a) 1179 segments analyzable on both imaging modalities and 61 segments rated as nonanalyzable on perfusion images; (b) the percentage of diseased segments was increased by 7.2 % when perfusion imaging was compared to the detailed reading of diagnostic images, and by 26.6 % when compared to the standard reading of images. At a patient level, the extent of peripheral CPE was higher on perfusion imaging, with a greater impact when compared to the standard reading of diagnostic images (number of patients with a greater number of diseased segments: n = 45; 72.6 % of the study population). Perfusion imaging allows recognition of a greater extent of peripheral CPE compared to diagnostic imaging. • Dual-energy computed tomography generates standard diagnostic imaging and lung perfusion analysis. • Depiction of CPE on central arteries relies on standard diagnostic imaging. • Detection of peripheral CPE is improved by perfusion imaging.

Gastrin-releasing peptide induces monocyte adhesion to vascular endothelium by upregulating endothelial adhesion molecules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Mi-Kyoung; Park, Hyun-Joo; Department of Dental Pharmacology, BK21 PLUS Project, School of Dentistry, Pusan National University, Yangsan 626-870

Gastrin-releasing peptide (GRP) is a neuropeptide that plays roles in various pathophysiological conditions including inflammatory diseases in peripheral tissues; however, little is known about whether GRP can directly regulate endothelial inflammatory processes. In this study, we showed that GRP promotes the adhesion of leukocytes to human umbilical vein endothelial cells (HUVECs) and the aortic endothelium. GRP increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by activating nuclear factor-κB (NF-κB) in endothelial cells. In addition, GRP activated extracellular signal-regulated kinase 1/2 (ERK1/2), p38MAPK, and AKT, and the inhibition of these signaling pathways significantly reduced GRP-inducedmore » monocyte adhesion to the endothelium. Overall, our results suggested that GRP may cause endothelial dysfunction, which could be of particular relevance in the development of vascular inflammatory disorders. - Highlights: • GRP induces adhesion of monocytes to vascular endothelium. • GRP increases the expression of endothelial adhesion molecules through the activation of NF-κB. • ERK1/2, p38MAPK, and Akt pathways are involved in the GRP-induced leukocyte adhesiveness to endothelium.« less

Teaching medical students ultrasound-guided vascular access - which learning method is best?

PubMed

Lian, Alwin; Rippey, James C R; Carr, Peter J

2017-05-15

Ultrasound is recommended to guide insertion of peripheral intravenous vascular cannulae (PIVC) where difficulty is experienced. Ultrasound machines are now common-place and junior doctors are often expected to be able to use them. The educational standards for this skill are highly varied, ranging from no education, to self-guided internet-based education, to formal, face-to-face traditional education. In an attempt to decide which educational technique our institution should introduce, a small pilot trial comparing educational techniques was designed. Thirty medical students were enrolled and allocated to one of three groups. PIVC placing ability was then observed, tested and graded on vascular access phantoms. The formal, face-to-face traditional education was rated best by the students, and had the highest success rate in PIVC placement, the improvement statistically significant compared to no education (p = 0.01) and trending towards significance when compared to self-directed internet-based education (p<0.06). The group receiving traditional face-to-face teaching on ultrasound-guided vascular access, performed significantly better than those not receiving education. As the number of ultrasound machines in clinical areas increases, it is important that education programs to support their safe and appropriate use are developed.