Improved differentiation between MS and vascular brain lesions using FLAIR* at 7 Tesla

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Kilsdonk, Iris D.; Wattjes, Mike P.; Lopez-Soriano, Alexandra; Jong, Marcus C. de; Graaf, Wolter L. de; Conijn, Mandy M.A.; Barkhof, Frederik [VU University Medical Center, Department of Radiology, De Boelelaan 1118, HZ, Amsterdam (Netherlands); Kuijer, Joost P.A. [VU University Medical Center, Department of Physics and Medical Technology, Amsterdam (Netherlands); Polman, Chris H. [VU University Medical Center, Department of Neurology, Amsterdam (Netherlands); Luijten, Peter R. [University Medical Center, Department of Radiology, Utrecht (Netherlands); Geurts, Jeroen J.G. [VU University, Department of Anatomy and Neurosciences, Amsterdam (Netherlands); Geerlings, Mirjam I. [University Medical Center, Julius Center for Health Sciences and Primary Care, Utrecht (Netherlands)

2014-04-15

To investigate whether a new magnetic resonance image (MRI) technique called T2*-weighted fluid attenuation inversion recovery (FLAIR*) can differentiate between multiple sclerosis (MS) and vascular brain lesions, at 7 Tesla (T). We examined 16 MS patients and 16 age-matched patients with (risk factors for) vascular disease. 3D-FLAIR and T2*-weighted images were combined into FLAIR* images. Lesion type and intensity, perivascular orientation and presence of a hypointense rim were analysed. In total, 433 cerebral lesions were detected in MS patients versus 86 lesions in vascular patients. Lesions in MS patients were significantly more often orientated in a perivascular manner: 74 % vs. 47 % (P < 0.001). Ten MS lesions (2.3 %) were surrounded by a hypointense rim on FLAIR*, and 24 MS lesions (5.5 %) were hypointense on T2*. No lesions in vascular patients showed any rim or hypointensity. Specificity of differentiating MS from vascular lesions on 7-T FLAIR* increased when the presence of a central vessel was taken into account (from 63 % to 88 %), most obviously for deep white matter lesions (from 69 % to 94 %). High sensitivity remained (81 %). 7-T FLAIR* improves differentiation between MS and vascular lesions based on lesion location, perivascular orientation and presence of hypointense (rims around) lesions. circle A new MRI technique T2*-weighted fluid attenuation inversion recovery (FLAIR*) was investigated. circle FLAIR* at 7-T MRI combines FLAIR and T2* images into a single image. circle FLAIR* at 7 T does not require enhancement with contrast agents. (orig.)

The unsuitability of implantable Doppler probes for the early detection of renal vascular complications - a porcine model for prevention of renal transplant loss

DEFF Research Database (Denmark)

Amdisen, Chris; Jespersen, Bente; Møldrup, Ulla

2017-01-01

Abstract Background: Vascular occlusion is a rare, but serious complication after kidney transplantation often resulting in graft loss. We therefore aimed to develop an experimental porcine model for stepwise reduction of the renal venous blood flow and to compare an implantable Doppler probe...... and microdialysis for fast detection of vascular occlusion. Methods: In 20 pigs, implantable Doppler probes were placed on the renal artery and vein and a microdialysis catheter was placed in the renal cortex. An arterial flowprobe served as gold standard. Following two-hour baseline measurements, the pigs were....../3 (66%) reduction in renal blood flow. The implantable Doppler probe was not able to detect flow changes until there was total venous occlusion. Microdialysis detected changes in local metabolism after both arterial and venous occlusion; the implantable Doppler probe could only detect vascular...

Quality improvement initiative: Preventative Surgical Site Infection Protocol in Vascular Surgery.

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Parizh, David; Ascher, Enrico; Raza Rizvi, Syed Ali; Hingorani, Anil; Amaturo, Michael; Johnson, Eric

2018-02-01

Objective A quality improvement initiative was employed to decrease single institution surgical site infection rate in open lower extremity revascularization procedures. In an attempt to lower patient morbidity, we developed and implemented the Preventative Surgical Site Infection Protocol in Vascular Surgery. Surgical site infections lead to prolonged hospital stays, adjunctive procedure, and additive costs. We employed targeted interventions to address the common risk factors that predispose patients to post-operative complications. Methods Retrospective review was performed between 2012 and 2016 for all surgical site infections after revascularization procedures of the lower extremity. A quality improvement protocol was initiated in January 2015. Primary outcome was the assessment of surgical site infection rate reduction in the pre-protocol vs. post-protocol era. Secondary outcomes evaluated patient demographics, closure method, perioperative antibiotic coverage, and management outcomes. Results Implementation of the protocol decreased the surgical site infection rate from 6.4% to 1.6% p = 0.0137). Patient demographics and comorbidities were assessed and failed to demonstrate a statistically significant difference among the infection and no-infection groups. Wound closure with monocryl suture vs. staple proved to be associated with decreased surgical site infection rate ( p site infections in the vascular surgery population are effective and necessary. Our data suggest that there may be benefit in the incorporation of MRSA and Gram-negative coverage as part of the Surgical Care Improvement Project perioperative guidelines.

Non-invasive vascular imaging: assessing tumour vascularity

International Nuclear Information System (INIS)

Delorme, S.; Knopp, M.V.

1998-01-01

Non-invasive assessment of vascularity is a new diagnostic approach to characterise tumours. Vascular assessment is based on the pathophysiology of tumour angiogenesis and its diagnostic implications for tumour biology, prognosis and therapy response. Two current techniques investigating vascular features in addition to morphology are Doppler ultrasonography and contrast-enhanced MRI. Diagnostic differentiation has been shown to be possible with Doppler, and a high degree of observed vascularity could be linked to an aggressive course of the disease. Dynamic MRI using gadolinium chelates is already used clinically to detect and differentiate tumours. The histological correlation shows that capillary permeability is increased in malignant tumours and is the best criterion for differentiation from benign processes. Permeability and perfusion factors seem to be more diagnostic than overall vessel density. New clinical applications are currently being established for therapy monitoring. Further instrumental developments will bring harmonic imaging in Doppler, and faster imaging techniques, higher spatial resolution and novel pharmacokinetic concepts in MRI. Upcoming contrast agents for both Doppler and MRI will further improve estimation of intratumoural blood volume and vascular permeability. (orig.)

Incorporation of bone marrow cells in pancreatic pseudoislets improves posttransplant vascularization and endocrine function.

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Christine Wittig

Full Text Available Failure of revascularization is known to be the major reason for the poor outcome of pancreatic islet transplantation. In this study, we analyzed whether pseudoislets composed of islet cells and bone marrow cells can improve vascularization and function of islet transplants. Pancreatic islets isolated from Syrian golden hamsters were dispersed into single cells for the generation of pseudoislets containing 4×10(3 cells. To create bone marrow cell-enriched pseudoislets 2×10(3 islet cells were co-cultured with 2×10(3 bone marrow cells. Pseudoislets and bone marrow cell-enriched pseudoislets were transplanted syngeneically into skinfold chambers to study graft vascularization by intravital fluorescence microscopy. Native islet transplants served as controls. Bone marrow cell-enriched pseudoislets showed a significantly improved vascularization compared to native islets and pseudoislets. Moreover, bone marrow cell-enriched pseudoislets but not pseudoislets normalized blood glucose levels after transplantation of 1000 islet equivalents under the kidney capsule of streptozotocin-induced diabetic animals, although the bone marrow cell-enriched pseudoislets contained only 50% of islet cells compared to pseudoislets and native islets. Fluorescence microscopy of bone marrow cell-enriched pseudoislets composed of bone marrow cells from GFP-expressing mice showed a distinct fraction of cells expressing both GFP and insulin, indicating a differentiation of bone marrow-derived cells to an insulin-producing cell-type. Thus, enrichment of pseudoislets by bone marrow cells enhances vascularization after transplantation and increases the amount of insulin-producing tissue. Accordingly, bone marrow cell-enriched pseudoislets may represent a novel approach to increase the success rate of islet transplantation.

Extravascular lung water and the pulmonary vascular permeability index may improve the definition of ARDS

OpenAIRE

Perel, Azriel

2013-01-01

The recent Berlin definition has made some improvements in the older definition of acute respiratory distress syndrome (ARDS), although the concepts and components of the definition remained largely unchanged. In an effort to improve both predictive and face validity, the Berlin panel has examined a number of additional measures that may reflect increased pulmonary vascular permeability, including extravascular lung water. The panel concluded that although extravascular lung water has improve...

Cognitive Impairment in Chronic Kidney Disease: Vascular Milieu and the Potential Therapeutic Role of Exercise

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Ulf G. Bronas

2017-01-01

Full Text Available Chronic kidney disease (CKD is considered a model of accelerated aging. More specifically, CKD leads to reduced physical functioning and increased frailty, increased vascular dysfunction, vascular calcification and arterial stiffness, high levels of systemic inflammation, and oxidative stress, as well as increased cognitive impairment. Increasing evidence suggests that the cognitive impairment associated with CKD may be related to cerebral small vessel disease and overall impairment in white matter integrity. The triad of poor physical function, vascular dysfunction, and cognitive impairment places patients living with CKD at an increased risk for loss of independence, poor health-related quality of life, morbidity, and mortality. The purpose of this review is to discuss the available evidence of cerebrovascular-renal axis and its interconnection with early and accelerated cognitive impairment in patients with CKD and the plausible role of exercise as a therapeutic modality. Understanding the cerebrovascular-renal axis pathophysiological link and its interconnection with physical function is important for clinicians in order to minimize the risk of loss of independence and improve quality of life in patients with CKD.

Long-term vascular contractility assay using genipin-modified muscular thin films

International Nuclear Information System (INIS)

Hald, Eric S; Steucke, Kerianne E; Reeves, Jack A; Win, Zaw; Alford, Patrick W

2014-01-01

Vascular disease is a leading cause of death globally and typically manifests chronically due to long-term maladaptive arterial growth and remodeling. To date, there is no in vitro technique for studying vascular function over relevant disease time courses that both mimics in vivo-like tissue structure and provides a simple readout of tissue stress. We aimed to extend tissue viability in our muscular thin film contractility assay by modifying the polydimethylsiloxane (PDMS) substrate with micropatterned genipin, allowing extracellular matrix turnover without cell loss. To achieve this, we developed a microfluidic delivery system to pattern genipin and extracellular matrix proteins on PDMS prior to cell seeding. Tissues constructed using this method showed improved viability and maintenance of in vivo-like lamellar structure. Functional contractility of tissues fabricated on genipin-modified substrates remained consistent throughout two weeks in culture. These results suggest that muscular thin films with genipin-modified PDMS substrates are a viable method for conducting functional studies of arterial growth and remodeling in vascular diseases. (paper)

Combined strategy of endothelial cells coating, Sertoli cells coculture and infusion improves vascularization and rejection protection of islet graft.

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Yang Li

Full Text Available Improving islet graft revascularization and inhibiting rejection become crucial tasks for prolonging islet graft survival. Endothelial cells (ECs are the basis of islet vascularization and Sertoli cells (SCs have the talent to provide nutritional support and exert immunosuppressive effects. We construct a combined strategy of ECs coating in the presence of nutritious and immune factors supplied by SCs in a co-culture system to investigate the effect of vascularization and rejection inhibition for islet graft. In vivo, the combined strategy improved the survival and vascularization as well as inhibited lymphocytes and inflammatory cytokines. In vitro, we found the combinatorial strategy improved the function of islets and the effect of ECs-coating on islets. Combined strategy treated islets revealed higher levels of anti-apoptotic signal molecules (Bcl-2 and HSP-32, survival and function related molecules (PDX-1, Ki-67, ERK1/2 and Akt and demonstrated increased vascular endothelial growth factor receptor 2 (KDR and angiogenesis signal molecules (FAk and PLC-γ. SCs effectively inhibited the activation of lymphocyte stimulated by islets and ECs. Predominantly immunosuppressive cytokines could be detected in culture supernatants of the SCs coculture group. These results suggest that ECs-coating and Sertoli cells co-culture or infusion synergistically enhance islet survival and function after transplantation.

Aerobic exercise reduces oxidative stress and improves vascular changes of small mesenteric and coronary arteries in hypertension.

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Roque, Fernanda R; Briones, Ana M; García-Redondo, Ana B; Galán, María; Martínez-Revelles, Sonia; Avendaño, Maria S; Cachofeiro, Victoria; Fernandes, Tiago; Vassallo, Dalton V; Oliveira, Edilamar M; Salaices, Mercedes

2013-02-01

Regular physical activity is an effective non-pharmacological therapy for prevention and control of hypertension. We investigated the effects of aerobic exercise training in vascular remodelling and in the mechanical and functional alterations of coronary and small mesenteric arteries from spontaneously hypertensive rats (SHR). Normotensive Wistar Kyoto (WKY), SHR and SHR trained on a treadmill for 12 weeks were used to evaluate vascular structural, mechanical and functional properties. Exercise did not affect lumen diameter, wall thickness and wall/lumen ratio but reduced vascular stiffness of coronary and mesenteric arteries from SHR. Exercise also reduced collagen deposition and normalized altered internal elastic lamina organization and expression of MMP-9 in mesenteric arteries from SHR. Exercise did not affect contractile responses of coronary arteries but improved the endothelium-dependent relaxation in SHR. In mesenteric arteries, training normalized the increased contractile responses induced by U46619 and by high concentrations of acetylcholine. In vessels from SHR, exercise normalized the effects of the NADPH oxidase inhibitor apocynin and the NOS inhibitor l-NAME in vasodilator or vasoconstrictor responses, normalized the increased O(2) (-) production and the reduced Cu/Zn superoxide dismutase expression and increased NO production. Exercise training of SHR improves endothelial function and vascular stiffness in coronary and small mesenteric arteries. This might be related to the concomitant decrease of oxidative stress and increase of NO bioavailability. Such effects demonstrate the beneficial effects of exercise on the vascular system and could contribute to a reduction in blood pressure. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Aerobic exercise reduces oxidative stress and improves vascular changes of small mesenteric and coronary arteries in hypertension

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Roque, Fernanda R; Briones, Ana M; García-Redondo, Ana B; Galán, María; Martínez-Revelles, Sonia; Avendaño, Maria S; Cachofeiro, Victoria; Fernandes, Tiago; Vassallo, Dalton V; Oliveira, Edilamar M; Salaices, Mercedes

2013-01-01

Background and Purpose Regular physical activity is an effective non-pharmacological therapy for prevention and control of hypertension. We investigated the effects of aerobic exercise training in vascular remodelling and in the mechanical and functional alterations of coronary and small mesenteric arteries from spontaneously hypertensive rats (SHR). Experimental Approach Normotensive Wistar Kyoto (WKY), SHR and SHR trained on a treadmill for 12 weeks were used to evaluate vascular structural, mechanical and functional properties. Key Results Exercise did not affect lumen diameter, wall thickness and wall/lumen ratio but reduced vascular stiffness of coronary and mesenteric arteries from SHR. Exercise also reduced collagen deposition and normalized altered internal elastic lamina organization and expression of MMP-9 in mesenteric arteries from SHR. Exercise did not affect contractile responses of coronary arteries but improved the endothelium-dependent relaxation in SHR. In mesenteric arteries, training normalized the increased contractile responses induced by U46619 and by high concentrations of acetylcholine. In vessels from SHR, exercise normalized the effects of the NADPH oxidase inhibitor apocynin and the NOS inhibitor l-NAME in vasodilator or vasoconstrictor responses, normalized the increased O2− production and the reduced Cu/Zn superoxide dismutase expression and increased NO production. Conclusions and Implications Exercise training of SHR improves endothelial function and vascular stiffness in coronary and small mesenteric arteries. This might be related to the concomitant decrease of oxidative stress and increase of NO bioavailability. Such effects demonstrate the beneficial effects of exercise on the vascular system and could contribute to a reduction in blood pressure. PMID:22994554

SLM Produced Porous Titanium Implant Improvements for Enhanced Vascularization and Osteoblast Seeding

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Julia Matena

2015-04-01

Full Text Available To improve well-known titanium implants, pores can be used for increasing bone formation and close bone-implant interface. Selective Laser Melting (SLM enables the production of any geometry and was used for implant production with 250-µm pore size. The used pore size supports vessel ingrowth, as bone formation is strongly dependent on fast vascularization. Additionally, proangiogenic factors promote implant vascularization. To functionalize the titanium with proangiogenic factors, polycaprolactone (PCL coating can be used. The following proangiogenic factors were examined: vascular endothelial growth factor (VEGF, high mobility group box 1 (HMGB1 and chemokine (C-X-C motif ligand 12 (CXCL12. As different surfaces lead to different cell reactions, titanium and PCL coating were compared. The growing into the porous titanium structure of primary osteoblasts was examined by cross sections. Primary osteoblasts seeded on the different surfaces were compared using Live Cell Imaging (LCI. Cross sections showed cells had proliferated, but not migrated after seven days. Although the cell count was lower on titanium PCL implants in LCI, the cell count and cell spreading area development showed promising results for titanium PCL implants. HMGB1 showed the highest migration capacity for stimulating the endothelial cell line. Future perspective would be the incorporation of HMGB1 into PCL polymer for the realization of a slow factor release.

SLM Produced Porous Titanium Implant Improvements for Enhanced Vascularization and Osteoblast Seeding

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Matena, Julia; Petersen, Svea; Gieseke, Matthias; Kampmann, Andreas; Teske, Michael; Beyerbach, Martin; Murua Escobar, Hugo; Haferkamp, Heinz; Gellrich, Nils-Claudius; Nolte, Ingo

2015-01-01

To improve well-known titanium implants, pores can be used for increasing bone formation and close bone-implant interface. Selective Laser Melting (SLM) enables the production of any geometry and was used for implant production with 250-µm pore size. The used pore size supports vessel ingrowth, as bone formation is strongly dependent on fast vascularization. Additionally, proangiogenic factors promote implant vascularization. To functionalize the titanium with proangiogenic factors, polycaprolactone (PCL) coating can be used. The following proangiogenic factors were examined: vascular endothelial growth factor (VEGF), high mobility group box 1 (HMGB1) and chemokine (C-X-C motif) ligand 12 (CXCL12). As different surfaces lead to different cell reactions, titanium and PCL coating were compared. The growing into the porous titanium structure of primary osteoblasts was examined by cross sections. Primary osteoblasts seeded on the different surfaces were compared using Live Cell Imaging (LCI). Cross sections showed cells had proliferated, but not migrated after seven days. Although the cell count was lower on titanium PCL implants in LCI, the cell count and cell spreading area development showed promising results for titanium PCL implants. HMGB1 showed the highest migration capacity for stimulating the endothelial cell line. Future perspective would be the incorporation of HMGB1 into PCL polymer for the realization of a slow factor release. PMID:25849656

Vacuum-assisted wound closure in vascular surgery - clinical and cost benefits in a developing country

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Končar Igor

2016-01-01

Full Text Available Background/Aim. Surgical and chronic wounds in vascular patients might contribute to limb loss and death. Vacuum-assisted closure (VAC - Kinetic Concepts, Inc. (KCI, has been increasingly used in Western Europe and the USA clinical practice for 15 years. Advantages of this method are faster wound healing, wound approximation, lower wound related treatment costs and improved quality of life during treatment. Evidence related to the usage of VAC therapy in vascular patients and cost effectiveness of VAC therapy in a developing country are lacking. The aim of this study was to explore results of VAC therapy in vascular surgery comparing to conventional methods and to test cost effects in a developing country like Serbia. Methods. All patients with wound infection or dehiscence operated at the tertiary vascular university clinic in the period from January 2011 - January 2012, were treated with VAC therapy. The primary endpoint was wound closure, while secondary endpoints were hospital stay, the number of weekly dressings, costs of wound care, working time of medical personnel. The patients were divided into groups according to the wound type and location: wound with exposed synthetic vascular implant (25%, laparotomy (13%, foot amputation (29%, major limb amputation (21%, fasciotomy (13%. The results of primary and secondary endpoint were compared with the results of conventional treatment during the previous year. Results. There was one death (1/42, 2.38% and one limb loss (1/12, 2.38% in the VAC group, and 8 deaths (8/38, 21.05% and 5 (5/38, 13.15% limb losses in the patients treated with conventional therapy. In the VAC group there was one groin bleeding (1/12, 2.38%, one groin reinfection (1/12, 2.38% and one resistance to therapy with a consequent limb loss. Costs of hospital stay (p < 0.001 and nursing time (p < 0.001 were reduced with VAC therapy in the group with exposed graft. Conclusion. VAC therapy is the effective method for care of

Vacuum-assisted wound closure in vascular surgery--clinical and cost benefits in a developing country.

Science.gov (United States)

Koncar, Igor; Cvetković, Slobodan; Dragas, Marko; Pejkić, Sinisa; Lazović, Goran; Banzić, Igor; Zuvela, Marinko; Marković, Miroslav; Davidović, Lazar

2016-01-01

BACKGROUND/AIM. Surgical and chronic wounds in vascular patients might contribute to limb loss and death. Vacuum-assisted closure (VAC)--Kinetic Concepts, Inc. (KCI), has been increasingly used in Western Europe and the U.S.A. clinical practice for 15 years. Advantages of this method are faster wound healing, wound approximation, lower wound related treatment costs and improved quality of life during treatment. Evidence related to the usage of VAC therapy in vascular patients and cost effectiveness of VAC therapy in a developing country are lacking. The aim of this study was to explore results of VAC therapy in vascular surgery comparing to conventional methods and to test cost effects in a developing country like Serbia. All patients with wound infection or dehiscence operated at the tertiary vascular university clinic in the period from January 2011-January 2012, were treated with VAC therapy. The primary endpoint was wound closure, while secondary endpoints were hospital stay, the number of weekly dressings, costs of wound care, working time of medical personnel. The patients were divided into groups according to the wound type and location: wound with exposed synthetic vascular implant (25%), laparotomy (13%), foot amputation (29%), major limb amputation (21%), fasciotomy (13%). The results of primary and secondary endpoint were compared with the results of conventional treatment during the previous year. There was one death (1/42, 2.38%) and one limb loss (1/12, 2.38%) in the VAC group, and 8 deaths (8/38, 21.05%) and 5 (5/38, 13.15%) limb losses in the patients treated with conventional therapy. In the VAC group there was one groin bleeding (1/12, 2.38%), one groin reinfection (1/12, 2.38%) and one resistance to therapy with a consequent limb loss. Costs of hospital stay (p VAC therapy in the group with exposed graft. VAC therapy is the effective method for care of complicated wounds in vascular surgery. Patients with infection of wound with the exposed

Omentopexy improves vascularization and decreases stricture formation of esophageal anastomoses in a dog model.

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Hayari, Lili; Hershko, Dan D; Shoshani, Hadas; Maor, Ron; Mordecovich, Daniel; Shoshani, Gideon

2004-04-01

Anastomotic strictures are common after primary esophageal anastomosis in pediatric patients. Recent studies provided evidence that omentopexy may improve vascularization of gastroesophageal anastomoses and decrease the rate of stricture-related complications. The effect of omentopexy on primary esophago-esophageal anastomosis, however, is unknown. The aim of the current study was to examine the role of omentopexy on the healing process of primary midesopageal anastomoses. Six dogs were operated on. A 5-cm portion of the midesophagus was resected, and continuity was restored by end-to-end anastomosis. In 3 dogs, an omental pedicle was placed around the anastomotic region. Eating patterns were recorded and functional swallowing was evaluated by fluoroscopic studies. Eight weeks after the operations, the experimental animals were killed and anastomotic lumen diameters and vascularization of the anastomotic sites were evaluated by radiographic studies and histologic examination, respectively. Two dogs in the omentopexy group were able to resume regular feeding, whereas none of the dogs in the control group were able to tolerate solid food intake. Fluoroscopic studies found preserved motility patterns of the esophagus in the omentoesophagopexy group, while prestenotic dilatation and delayed food clearance through the anastomosis were observed in the control group. Histologically, neovascularization was observed at the anastomotic site in the omentoesophagopexy group in contrast to the marked degree of fibrosis displayed in the control group. Omentopexy may improve vascularization and decrease stricture formation after primary esophagoesophageal anastomosis.

Advanced Maternal Age Worsens Postpartum Vascular Function

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Jude S. Morton

2017-06-01

Full Text Available The age at which women experience their first pregnancy has increased throughout the decades. Pregnancy has an important influence on maternal short- and long-term cardiovascular outcomes. Pregnancy at an advanced maternal age increases maternal risk of gestational diabetes, preeclampsia, placenta previa and caesarian delivery; complications which predict worsened cardiovascular health in later years. Aging also independently increases the risk of cardiovascular disease; therefore, combined risk in women of advanced maternal age may lead to detrimental cardiovascular outcomes later in life. We hypothesized that pregnancy at an advanced maternal age would lead to postpartum vascular dysfunction. We used a reproductively aged rat model to investigate vascular function in never pregnant (virgin, previously pregnant (postpartum and previously mated but never delivered (nulliparous rats at approximately 13.5 months of age (3 months postpartum or equivalent. Nulliparous rats, in which pregnancy was spontaneously lost, demonstrated significantly reduced aortic relaxation responses (methylcholine [MCh] Emax: 54.2 ± 12.6% vs. virgin and postpartum rats (MCh Emax: 84.8 ± 3.5% and 84.7 ± 3.2% respectively; suggesting pregnancy loss causes a worsened vascular pathology. Oxidized LDL reduced relaxation to MCh in aorta from virgin and postpartum, but not nulliparous rats, with an increased contribution of the LOX-1 receptor in the postpartum group. Further, in mesenteric arteries from postpartum rats, endothelium-derived hyperpolarization (EDH-mediated vasodilation was reduced and a constrictive prostaglandin effect was apparent. In conclusion, aged postpartum rats exhibited vascular dysfunction, while rats which had pregnancy loss demonstrated a distinct vascular pathology. These data demonstrate mechanisms which may lead to worsened outcomes at an advanced maternal age; including early pregnancy loss and later life cardiovascular dysfunction.

Diabetes and Retinal Vascular Dysfunction

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Eui Seok Shin

2014-01-01

Full Text Available Diabetes predominantly affects the microvascular circulation of the retina resulting in a range of structural changes unique to this tissue. These changes ultimately lead to altered permeability, hyperproliferation of endothelial cells and edema, and abnormal vascularization of the retina with resulting loss of vision. Enhanced production of inflammatory mediators and oxidative stress are primary insults with significant contribution to the pathogenesis of diabetic retinopathy (DR. We have determined the identity of the retinal vascular cells affected by hyperglycemia, and have delineated the cell autonomous impact of high glucose on function of these cells. We discuss some of the high glucose specific changes in retinal vascular cells and their contribution to retinal vascular dysfunction. This knowledge provides novel insight into the molecular and cellular defects contributing to the development and progression of diabetic retinopathy, and will aid in the development of innovative, as well as target specific therapeutic approaches for prevention and treatment of DR.

Fractional non-ablative laser-assisted drug delivery leads to improvement in male and female pattern hair loss.

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Bertin, Ana Carina Junqueira; Vilarinho, Adriana; Junqueira, Ana Lúcia Ariano

2018-02-16

Androgenetic alopecia, also known as male and female pattern hair loss, is a very prevalent condition; however, approved therapeutic options are limited. Fractionated laser has been proposed to assist in penetration of topical medications to the cutaneous tissue. We present four cases of androgenetic alopecia that underwent treatment with a non-ablative erbium glass fractional laser followed by the application of topical finasteride 0,05% and growth factors including basic fibroblast growth factor, insulin-like growth factor, vascular endothelial growth factor, and copper peptide 1%. During all laser treatment sessions, eight passes were performed, at 7 mJ, 3-9% of coverage and density of 120 mzt/cm 2 . A positive response was observed in all of the four patients. Photographs taken 2 weeks after the last session showed improvement in hair regrowth and density. No significant side effects were observed.

Moderate Champagne consumption promotes an acute improvement in acute endothelial-independent vascular function in healthy human volunteers.

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Vauzour, David; Houseman, Emily J; George, Trevor W; Corona, Giulia; Garnotel, Roselyne; Jackson, Kim G; Sellier, Christelle; Gillery, Philippe; Kennedy, Orla B; Lovegrove, Julie A; Spencer, Jeremy P E

2010-04-01

Epidemiological studies have suggested an inverse correlation between red wine consumption and the incidence of CVD. However, Champagne wine has not been fully investigated for its cardioprotective potential. In order to assess whether acute and moderate Champagne wine consumption is capable of modulating vascular function, we performed a randomised, placebo-controlled, cross-over intervention trial. We show that consumption of Champagne wine, but not a control matched for alcohol, carbohydrate and fruit-derived acid content, induced an acute change in endothelium-independent vasodilatation at 4 and 8 h post-consumption. Although both Champagne wine and the control also induced an increase in endothelium-dependent vascular reactivity at 4 h, there was no significant difference between the vascular effects induced by Champagne or the control at any time point. These effects were accompanied by an acute decrease in the concentration of matrix metalloproteinase (MMP-9), a significant decrease in plasma levels of oxidising species and an increase in urinary excretion of a number of phenolic metabolites. In particular, the mean total excretion of hippuric acid, protocatechuic acid and isoferulic acid were all significantly greater following the Champagne wine intervention compared with the control intervention. Our data suggest that a daily moderate consumption of Champagne wine may improve vascular performance via the delivery of phenolic constituents capable of improving NO bioavailability and reducing matrix metalloproteinase activity.

Preparation and features of polycaprolactone vascular grafts with the incorporated vascular endothelial growth factor

Energy Technology Data Exchange (ETDEWEB)

Sevostyanova, V. V., E-mail: sevostyanova.victoria@gmail.com; Khodyrevskaya, Y. I.; Glushkova, T. V.; Antonova, L. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S. [Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo (Russian Federation)

2015-10-27

The development of tissue-engineered small-diameter vascular grafts is an urgent issue in cardiovascular surgery. In this study, we assessed how the incorporation of the vascular endothelial growth factor (VEGF) affects morphological and mechanical properties of polycaprolactone (PCL) vascular grafts along with its release kinetics. Vascular grafts were prepared using two-phase electrospinning. In pursuing our aims, we performed scanning electron microscopy, mechanical testing, and enzyme-linked immunosorbent assay. Our results demonstrated the preservation of a highly porous structure and improvement of PCL/VEGF scaffold mechanical properties as compared to PCL grafts. A prolonged VEGF release testifies the use of this construct as a scaffold for tissue-engineered vascular grafts.

Relaxin as a natural agent for vascular health

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Daniele Bani

2008-06-01

Full Text Available Daniele BaniDepartment of Anatomy, Histology and Forensic Medicine, Sect. Histology, University of Florence, ItalyAbstract: Hypertension, atherothrombosis, myocardial infarction, stroke, peripheral vascular disease, and renal failure are the main manifestations of cardiovascular disease (CVD, the leading cause of death and disability in developed countries. Continuing insight into the pathophysiology of CVD can allow identification of effective therapeutic strategies to reduce the occurrence of death and/or severe disabilities. In this context, a healthy endothelium is deemed crucial to proper functioning and maintenance of anatomical integrity of the vascular system in many organs. Of note, epidemiologic studies indicate that the incidence of CVD in women is very low until menopause and increases sharply thereafter. The loss of protection against CVD in post-menopausal women has been chiefly attributed to ovarian steroid deficiency. However, besides steroids, the ovary also produces the peptide hormone relaxin (RLX, which provides potent vasoactive effects which render it the most likely candidate as the elusive physiological shield against CVD in fertile women. In particular, RLX has a specific relaxant effect on peripheral and coronary vasculature, exerted by the stimulation of endogenous nitric oxide (NO generation by cells of the vascular wall, and can induce angiogenesis. Moreover, RLX inhibits the activation of inflammatory leukocytes and platelets, which play a key role in CVD. Experimental studies performed in vascular and blood cell in vitro and in animal models of vascular dysfunction, as well as pioneer clinical observations, have provided evidence that RLX can prevent and/or improve CVD, thus offering background to clinical trials aimed at exploring the broad therapeutic potential of human recombinant RLX as a new cardiovascular drug.Keywords: relaxin, blood vessels, endothelial cells, vascular smooth muscle, nitric oxide

Combined treatment with atorvastatin and imipenem improves survival and vascular functions in mouse model of sepsis.

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Choudhury, Soumen; Kannan, Kandasamy; Pule Addison, M; Darzi, Sazad A; Singh, Vishakha; Singh, Thakur Uttam; Thangamalai, Ramasamy; Dash, Jeevan Ranjan; Parida, Subhashree; Debroy, Biplab; Paul, Avishek; Mishra, Santosh Kumar

2015-08-01

We have recently reported that pre-treatment, but not the post-treatment with atorvastatin showed survival benefit and improved hemodynamic functions in cecal ligation and puncture (CLP) model of sepsis in mice. Here we examined whether combined treatment with atorvastatin and imipenem after onset of sepsis can prolong survival and improve vascular functions. At 6 and 18h after sepsis induction, treatment with atorvastatin plus imipenem, atorvastatin or imipenem alone or placebo was initiated. Ex vivo experiments were done on mouse aorta to examine the vascular reactivity to nor-adrenaline and acetylcholine and mRNA expressions of α1D AR, GRK2 and eNOS. Atorvastatin plus imipenem extended the survival time to 56.00±4.62h from 20.00±1.66h observed in CLP mice. The survival time with atorvastatin or imipenem alone was 20.50±1.89h and 27.00±4.09h, respectively. The combined treatment reversed the hyporeactivity to nor-adrenaline through preservation of α1D AR mRNA/protein expression and reversal of α1D AR desensitization mediated by GRK2/Gβγ pathway. The treatment also restored endothelium-dependent relaxation to ACh through restoration of aortic eNOS mRNA expression and NO availability. In conclusion, combined treatment with atorvastatin and imipenem exhibited survival benefit and improved vascular functions in septic mice. Copyright © 2015 Elsevier Inc. All rights reserved.

Registry and health insurance claims data in vascular research and quality improvement.

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Behrendt, Christian-Alexander; Heidemann, Franziska; Rieß, Henrik Christian; Stoberock, Konstanze; Debus, Sebastian Eike

2017-01-01

The expansion of procedures in multidisciplinary vascular medicine has sparked a controversy regarding measures of quality improvement. In addition to primary registries, the use of health insurance claims data is becoming of increasing importance. However, due to the fact that health insurance claims data are not collected for scientific evaluation but rather for reimbursement purposes, meticulous validation is necessary before and during usage in research and quality improvement matters. This review highlights the advantages and disadvantages of such data sources. A recent comprehensive expert opinion panel examined the use of health insurance claims data and other administrative data sources in medicine. Results from several studies concerning the validity of administrative data varied significantly. Validity of these data sources depends on the clinical relevance of the diagnoses considered. The rate of implausible information was 0.04 %, while the validity of the considered diagnoses varied between 80 and 97 % across multiple validation studies. A matching study between health insurance claims data of the third-largest German health insurance provider, DAK-Gesundheit, and a prospective primary registry of the German Society for Vascular Surgery demonstrated a good level of validity regarding the mortality of endovascular and open surgical treatment of abdominal aortic aneurysm in German hospitals. In addition, a large-scale international comparison of administrative data for the same disorder presented important results in treatment reality, which differed from those from earlier randomized controlled trials. The importance of administrative data for research and quality improvement will continue to increase in the future. When discussing the internal and external validity of this data source, one has to distinguish not only between its intended usage (research vs. quality improvement), but also between the included diseases and/or treatment procedures

Extravascular lung water and the pulmonary vascular permeability index may improve the definition of ARDS.

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Perel, Azriel

2013-01-24

The recent Berlin definition has made some improvements in the older definition of acute respiratory distress syndrome (ARDS), although the concepts and components of the definition remained largely unchanged. In an effort to improve both predictive and face validity, the Berlin panel has examined a number of additional measures that may reflect increased pulmonary vascular permeability, including extravascular lung water. The panel concluded that although extravascular lung water has improved face validity and higher values are associated with mortality, it is infeasible to mandate on the basis of availability and the fact that it does not distinguish between hydrostatic and inflammatory pulmonary edema. However, the results of a multi-institutional study that appeared in the previous issue of Critical Care show that this latter reservation may not necessarily be true. By using extravascular lung water and the pulmonary vascular permeability index, both of which are derived from transpulmonary thermodilution, the authors could successfully differentiate between patients with ARDS and other patients in respiratory failure due to either cardiogenic edema or pleural effusion with atelectasis. This commentary discusses the merits and limitations of this study in view of the potential improvement that transpulmonary thermodilution may bring to the definition of ARDS.

Vascular dementia: Facts and controversies

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Pavlović Aleksandra

2013-01-01

Full Text Available Vascular dementia (VaD is the second most frequent dementia after Alzheimer’s disease, and is diagnosed during lifetime in 20% of demented patients. Five­year survival rate in VaD is 39%, while it is estimated to be 75% in healthy persons of the same age. It is therefore important to make correct diagnosis of VaD early in the course of the disease. Risk factors for VaD are identical to stroke risk factors, and there are significant possibilities for the prevention of vascular cognitive decline. Cognitive decline develops acutely or step­by­step within three months after stroke, but more gradual progression of intellectual decline is also possible. Neurological examination can reveal pyramidal and extrapyramidal signs, pseudobulbar palsy, gait disturbance and urinary incontinence. Neuropsychological profile comprises the loss of cognitive set shifting, decline in word fluency, verbal learning difficulties, perseverations, difficulties in complex figure copying, and in patients with cortically located lesions also problems with speech and praxia. The basis of the diagnosis is, besides history, neurological examination and neuropsychological assessment, computed tomography and/ or magnetic resonance brain imaging. Vascular risk factors control is the most important measure in VaD prevention. Modern guidelines for the treatment of cognitive decline in VaD emphasize that donepezil can be useful in the improvement of cognitive status at the level of Class IIa recommendation at the level of evidence A, while memantine may be useful in patients with mixed VaD and Alzheimer’s disease dementia. [Projekat Ministarstva nauke Republike Srbije, br. 175022 i br. 175033

Use of 3D models of vascular rings and slings to improve resident education.

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Jones, Trahern W; Seckeler, Michael D

2017-09-01

Three-dimensional (3D) printing is a manufacturing method by which an object is created in an additive process, and can be used with medical imaging data to generate accurate physical reproductions of organs and tissues for a variety of applications. We hypothesized that using 3D printed models of congenital cardiovascular lesions to supplement an educational lecture would improve learners' scores on a board-style examination. Patients with normal and abnormal aortic arches were selected and anonymized to generate 3D printed models. A cohort of pediatric and combined pediatric/emergency medicine residents were then randomized to intervention and control groups. Each participant was given a subjective survey and an objective board-style pretest. Each group received the same 20-minutes lecture on vascular rings and slings. During the intervention group's lecture, 3D printed physical models of each lesion were distributed for inspection. After each lecture, both groups completed the same subjective survey and objective board-style test to assess their comfort with and postlecture knowledge of vascular rings. There were no differences in the basic demographics of the two groups. After the lectures, both groups' subjective comfort levels increased. Both groups' scores on the objective test improved, but the intervention group scored higher on the posttest. This study demonstrated a measurable gain in knowledge about vascular rings and pulmonary artery slings with the addition of 3D printed models of the defects. Future applications of this teaching modality could extend to other congenital cardiac lesions and different learners. © 2017 Wiley Periodicals, Inc.

Adipose derived stromal vascular fraction improves early tendon healing: an experimental study in rabbits

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Mehdi Behfar

2011-11-01

Full Text Available Tendon never restores the complete biological and mechanical properties after healing. Bone marrow and recently adipose tissue have been used as the sources of mesenchymal stem cells, which have been proven to enhance tendon healing. Stromal vascular fraction (SVF, derived from adipose tissue by an enzymatic digestion, represents an alternative source of multipotent cells, which undergo differentiation into multiple lineages to be used in regenerative medicine. In the present study, we investigated potentials of this source on tendon healing. Twenty rabbits were divided into control and treatment groups. Five rabbits were used as donors of adipose tissue. The injury model was unilateral complete transection through the middle one third of deep digital flexor tendon. Immediately after suture repair, either fresh stromal vascular fraction from enzymatic digestion of adipose tissue or placebo was intratendinously injected into the suture site in treatments and controls, respectively. Cast immobilization was continued for two weeks after surgery. Animals were sacrificed at the third week and tendons underwent histological, immunohistochemical, and mechanical evaluations. By histology, improved fibrillar organization and remodeling of neotendon were observed in treatment group. Immunohistochemistry revealed an insignificant increase in collagen type III and I expression in treatments over controls. Mechanical testing showed significant increase in maximum load and energy absorption in SVF treated tendons. The present study showed that intratendinous injection of uncultured adipose derived stromal vascular fraction improved structural and mechanical properties of repaired tendon and it could be an effective modality for treating tendon laceration.

The pathology and pathophysiology of vascular dementia.

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Kalaria, Raj N

2017-12-19

Vascular dementia (VaD) is widely recognised as the second most common type of dementia. Consensus and accurate diagnosis of clinically suspected VaD relies on wide-ranging clinical, neuropsychological and neuroimaging measures in life but more importantly pathological confirmation. Factors defining subtypes of VaD include the nature and extent of vascular pathologies, degree of involvement of extra and intracranial vessels and the anatomical location of tissue changes as well as time after the initial vascular event. Atherosclerotic and cardioembolic diseases combined appear the most common subtypes of vascular brain injury. In recent years, cerebral small vessel disease (SVD) has gained prominence worldwide as an important substrate of cognitive impairment. SVD is characterised by arteriolosclerosis, lacunar infarcts and cortical and subcortical microinfarcts and diffuse white matter changes, which involve myelin loss and axonal abnormalities. Global brain atrophy and focal degeneration of the cerebrum including medial temporal lobe atrophy are also features of VaD similar to Alzheimer's disease. Hereditary arteriopathies have provided insights into the mechanisms of dementia particularly how arteriolosclerosis, a major contributor of SVD promotes cognitive impairment. Recently developed and validated neuropathology guidelines indicated that the best predictors of vascular cognitive impairment were small or lacunar infarcts, microinfarcts, perivascular space dilation, myelin loss, arteriolosclerosis and leptomeningeal cerebral amyloid angiopathy. While these substrates do not suggest high specificity, VaD is likely defined by key neuronal and dendro-synaptic changes resulting in executive dysfunction and related cognitive deficits. Greater understanding of the molecular pathology is needed to clearly define microvascular disease and vascular substrates of dementia. Copyright © 2017 Elsevier Ltd. All rights reserved.

Treating fat grafts with human endothelial progenitor cells promotes their vascularization and improves their survival in diabetes mellitus.

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Hamed, Saher; Ben-Nun, Ohad; Egozi, Dana; Keren, Aviad; Malyarova, Nastya; Kruchevsky, Danny; Gilhar, Amos; Ullmann, Yehuda

2012-10-01

Bone marrow-derived endothelial progenitor cells are required for vascularization of a fat graft to form a functional microvasculature within the graft and to facilitate its integration into the surrounding tissues. Organ transplantation carries a high risk of graft loss and rejection in patients with diabetes mellitus because endothelial progenitor cell function is impaired. The authors investigated the influence of endothelial progenitor cell treatment on the phenotype and survival of human fat grafts in immunocompromised mice with experimentally induced diabetes mellitus. The authors injected 1 ml of human fat tissue into the scalps of 14 nondiabetic and 28 diabetic immunocompromised mice, and then treated some of the grafts with endothelial progenitor cells that was isolated from the blood of a human donor. The phenotype of the endothelial progenitor cell-treated fat grafts from the 14 diabetic mice was compared with that of the untreated fat grafts from 14 nondiabetic and 14 diabetic mice, 18 days and 15 weeks after fat transplantation. Determination of graft phenotype included measurements of weight and volume, vascular endothelial growth factor levels, vascular endothelial growth factor receptor-2, endothelial nitric oxide synthase, and caspase 3 expression levels, and histologic analysis of the extent of vascularization. The untreated grafts from the diabetic mice were fully resorbed 15 weeks after fat transplantation. The phenotype of endothelial progenitor cell-treated fat grafts from the diabetic mice was similar to that of the untreated fat grafts from the nondiabetic mice. Endothelial progenitor cell treatment of transplanted fat can increase the survival of a fat graft by inducing its vascularization and decreasing the extent of apoptosis.

Vascular plants promote ancient peatland carbon loss with climate warming.

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Walker, Tom N; Garnett, Mark H; Ward, Susan E; Oakley, Simon; Bardgett, Richard D; Ostle, Nicholas J

2016-05-01

Northern peatlands have accumulated one third of the Earth's soil carbon stock since the last Ice Age. Rapid warming across northern biomes threatens to accelerate rates of peatland ecosystem respiration. Despite compensatory increases in net primary production, greater ecosystem respiration could signal the release of ancient, century- to millennia-old carbon from the peatland organic matter stock. Warming has already been shown to promote ancient peatland carbon release, but, despite the key role of vegetation in carbon dynamics, little is known about how plants influence the source of peatland ecosystem respiration. Here, we address this issue using in situ (14)C measurements of ecosystem respiration on an established peatland warming and vegetation manipulation experiment. Results show that warming of approximately 1 °C promotes respiration of ancient peatland carbon (up to 2100 years old) when dwarf-shrubs or graminoids are present, an effect not observed when only bryophytes are present. We demonstrate that warming likely promotes ancient peatland carbon release via its control over organic inputs from vascular plants. Our findings suggest that dwarf-shrubs and graminoids prime microbial decomposition of previously 'locked-up' organic matter from potentially deep in the peat profile, facilitating liberation of ancient carbon as CO2. Furthermore, such plant-induced peat respiration could contribute up to 40% of ecosystem CO2 emissions. If consistent across other subarctic and arctic ecosystems, this represents a considerable fraction of ecosystem respiration that is currently not acknowledged by global carbon cycle models. Ultimately, greater contribution of ancient carbon to ecosystem respiration may signal the loss of a previously stable peatland carbon pool, creating potential feedbacks to future climate change. © 2016 John Wiley & Sons Ltd.

Evaluation of a novel thermosensitive heparin-poloxamer hydrogel for improving vascular anastomosis quality and safety in a rabbit model.

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Ying-Zheng Zhao

Full Text Available Despite progress in the design of advanced surgical techniques, stenosis recurs in a large percentage of vascular anastomosis. In this study, a novel heparin-poloxamer (HP hydrogel was designed and its effects for improving the quality and safety of vascular anastomosis were studied. HP copolymer was synthesized and its structure was confirmed by Fourier transform infrared spectroscopy (FTIR and nuclear magnetic resonance spectroscopy ((1H-NMR. Hydrogels containing HP were prepared and their important characteristics related to the application in vascular anastomosis including gelation temperature, rheological behaviour and micromorphology were measured. Vascular anastomosis were performed on the right common carotid arteries of rabbits, and the in vivo efficiency and safety of HP hydrogel to achieve vascular anastomosis was verified and compared with Poloxamer 407 hydrogel and the conventional hand-sewn method using Doppler ultrasound, CT angiograms, scanning electron microscopy (SEM and histological technique. Our results showed that HP copolymer displayed special gel-sol-gel phase transition behavior with increasing temperature from 5 to 60 °C. HP hydrogel prepared from 18 wt% HP solution had a porous sponge-like structure, with gelation temperature at approximately 38 °C and maximum elastic modulus at 10,000 Pa. In animal studies, imaging and histological examination of rabbit common jugular artery confirmed that HP hydrogel group had similar equivalent patency, flow and burst strength as Poloxamer 407 group. Moreover, HP hydrogel was superior to poloxamer 407 hydrogel and hand-sewn method for restoring the functions and epithelial structure of the broken vessel junctions after operation. By combining the advantages of heparin and poloxamer 407, HP hydrogel holds high promise for improving vascular anastomosis quality and safety.

Connections matter: channeled hydrogels to improve vascularization.

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Muehleder, Severin; Ovsianikov, Aleksandr; Zipperle, Johannes; Redl, Heinz; Holnthoner, Wolfgang

2014-01-01

The use of cell-laden hydrogels to engineer soft tissue has been emerging within the past years. Despite, several newly developed and sophisticated techniques to encapsulate different cell types the importance of vascularization of the engineered constructs is often underestimated. As a result, cell death within a construct leads to impaired function and inclusion of the implant. Here, we discuss the fabrication of hollow channels within hydrogels as a promising strategy to facilitate vascularization. Furthermore, we present an overview on the feasible use of removable spacers, 3D laser-, and planar processing strategies to create channels within hydrogels. The implementation of these structures promotes control over cell distribution and increases oxygen transport and nutrient supply in vitro. However, many studies lack the use of endothelial cells in their approaches leaving out an important factor to enhance vessel ingrowth and anastomosis formation upon implantation. In addition, the adequate endothelial cell type needs to be considered to make these approaches bridge the gap to in vivo applications.

The Soluble Epoxide Hydrolase Inhibitor AR9281 Decreases Blood Pressure, Ameliorates Renal Injury and Improves Vascular Function in Hypertension

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Sean Shaw

2009-12-01

Full Text Available Soluble epoxide hydrolase inhibitors (sEHIs are demonstrating promise as potential pharmaceutical agents for the treatment of cardiovascular disease, diabetes, inflammation, and kidney disease. The present study determined the ability of a first-inclass sEHI, AR9281, to decrease blood pressure, improve vascular function, and decrease renal inflammation and injury in angiotensin hypertension. Rats were infused with angiotensin and AR9281 was given orally during the 14-day infusion period. Systolic blood pressure averaged 180 ± 5 mmHg in vehicle treated and AR9281 treatment significantly lowered blood pressure to 142 ± 7 mmHg in angiotensin hypertension. Histological analysis demonstrated decreased injury to the juxtamedullary glomeruli. Renal expression of inflammatory genes was increased in angiotensin hypertension and two weeks of AR9281 treatment decreased this index of renal inflammation. Vascular function in angiotensin hypertension was also improved by AR9281 treatment. Decreased afferent arteriolar and mesenteric resistance endothelial dependent dilator responses were ameliorated by AR9281 treatment of angiotensin hypertensive rats. These data demonstrate that the first-in-class sEHI, AR9281, lowers blood pressure, improves vascular function and reduces renal damage in angiotensin hypertension.

Asthma and obesity: does weight loss improve asthma control? a systematic review

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Juel CTB

2012-06-01

Full Text Available Caroline Trunk-Black Juel,1 Zarqa Ali,1 Lisbeth Nilas,2 Charlotte Suppli Ulrik11Respiratory Section, Internal Medicine Unit, 2Department of Obstetrics and Gynaecology, Hvidovre Hospital and University of Copenhagen, Hvidovre, DenmarkAim and methods: Obesity is a major health problem, and obesity is associated with a high incidence of asthma and poor asthma control. The aim of the present paper is to systematically review the current knowledge of the effect on overall asthma control of weight reduction in overweight and obese adults with asthma.Results: Weight loss in obese individuals with doctor-diagnosed asthma is associated with a 48%–100% remission of asthma symptoms and use of asthma medication. Published studies, furthermore, reveal that weight loss in obese asthmatics improves asthma control, and that especially surgically induced weight loss results in significant improvements in asthma severity, use of asthma medication, dyspnoea, exercise tolerance, and acute exacerbations, including hospitalizations due to asthma. Furthermore, weight loss in obese asthmatics is associated with improvements in level of lung function and airway responsiveness to inhaled methacholine, whereas no significant improvements have been observed in exhaled nitric oxide or other markers of eosinophilic airway inflammation.Conclusion: Overweight and obese adults with asthma experience a high symptomatic remission rate and significant improvements in asthma control, including objective measures of disease activity, after weight loss. Although these positive effects of weight loss on asthma-related health outcomes seem not to be accompanied by remission or improvements in markers of eosinophilic airway inflammation, it has potentially important implications for the future burden of asthma.Keywords: asthma, weight loss, diet, bariatric surgery, asthma control

Vascular-targeted therapies for Duchenne muscular dystrophy

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2013-01-01

Duchenne muscular dystrophy (DMD) is the most common muscular dystrophy and an X-linked recessive, progressive muscle wasting disease caused by the absence of a functional dystrophin protein. Dystrophin has a structural role as a cytoskeletal stabilization protein and protects cells against contraction-induced damage. Dystrophin also serves a signaling role through mechanotransduction of forces and localization of neuronal nitric oxide synthase (nNOS), which produces nitric oxide (NO) to facilitate vasorelaxation. In DMD, the signaling defects produce inadequate tissue perfusion caused by functional ischemia due to a diminished ability to respond to shear stress induced endothelium-dependent dilation. Additionally, the structural defects seen in DMD render myocytes with an increased susceptibility to mechanical stress. The combination of both defects is necessary to generate myocyte damage, which induces successive rounds of myofiber degeneration and regeneration, loss of calcium homeostasis, chronic inflammatory response, fibrosis, and myonecrosis. In individuals with DMD, these processes inevitably cause loss of ambulation shortly after the first decade and an abbreviated life with death in the third or fourth decade due to cardio-respiratory anomalies. There is no known cure for DMD, and although the culpable gene has been identified for more than twenty years, research on treatments has produced few clinically relevant results. Several recent studies on novel DMD therapeutics are vascular targeted and focused on attenuating the inherent functional ischemia. One approach improves vasorelaxation capacity through pharmaceutical inhibition of either phosphodiesterase 5 (PDE5) or angiotensin-converting enzyme (ACE). Another approach increases the density of the underlying vascular network by inducing angiogenesis, and this has been accomplished through either direct delivery of vascular endothelial growth factor (VEGF) or by downregulating the VEGF decoy

Delayed sodium (18)F-fluoride PET/CT imaging does not improve quantification of vascular calcification metabolism

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Blomberg, Björn Alexander; Thomassen, Anders; Takx, Richard A P

2014-01-01

This study aimed to determine if delayed sodium (18)F-fluoride (Na(18)F) PET/CT imaging improves quantification of vascular calcification metabolism. Blood-pool activity can disturb the arterial Na(18)F signal. With time, blood-pool activity declines. Therefore, delayed imaging can potentially...

Using biplanar fluoroscopy to guide radiopaque vascular injections: a new method for vascular imaging.

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Haley D O'Brien

Full Text Available Studying vascular anatomy, especially in the context of relationships with hard tissues, is of great interest to biologists. Vascular studies have provided significant insight into physiology, function, phylogenetic relationships, and evolutionary patterns. Injection of resin or latex into the vascular system has been a standard technique for decades. There has been a recent surge in popularity of more modern methods, especially radiopaque latex vascular injection followed by CT scanning and digital "dissection." This technique best displays both blood vessels and bone, and allows injections to be performed on cadaveric specimens. Vascular injection is risky, however, because it is not a standardizable technique, as each specimen is variable with regard to injection pressure and timing. Moreover, it is not possible to view the perfusion of injection medium throughout the vascular system of interest. Both data and rare specimens can therefore be lost due to poor or excessive perfusion. Here, we use biplanar video fluoroscopy as a technique to guide craniovascular radiopaque latex injection. Cadaveric domestic pigs (Sus scrofa domestica and white-tailed deer (Odocoileus virginianus were injected with radiopaque latex under guidance of fluoroscopy. This method was found to enable adjustments, in real-time, to the rate, location, and pressure at which latex is injected in order to avoid data and specimen loss. In addition to visualizing the injection process, this technique can be used to determine flow patterns, and has facilitated the development of consistent markers for complete perfusion.

Inhibition of Vascular c-Jun N-Terminal Kinase 2 Improves Obesity-Induced Endothelial Dysfunction After Roux-en-Y Gastric Bypass.

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Doytcheva, Petia; Bächler, Thomas; Tarasco, Erika; Marzolla, Vincenzo; Engeli, Michael; Pellegrini, Giovanni; Stivala, Simona; Rohrer, Lucia; Tona, Francesco; Camici, Giovanni G; Vanhoutte, Paul M; Matter, Christian M; Lutz, Thomas A; Lüscher, Thomas F; Osto, Elena

2017-11-14

Roux-en-Y gastric bypass (RYGB) reduces obesity-associated comorbidities and cardiovascular mortality. RYGB improves endothelial dysfunction, reducing c-Jun N-terminal kinase (JNK) vascular phosphorylation. JNK activation links obesity with insulin resistance and endothelial dysfunction. Herein, we examined whether JNK1 or JNK2 mediates obesity-induced endothelial dysfunction and if pharmacological JNK inhibition can mimic RYGB vascular benefits. After 7 weeks of a high-fat high-cholesterol diet, obese rats underwent RYGB or sham surgery; sham-operated ad libitum-fed rats received, for 8 days, either the control peptide D-TAT or the JNK peptide inhibitor D-JNKi-1 (20 mg/kg per day subcutaneous). JNK peptide inhibitor D-JNKi-1 treatment improved endothelial vasorelaxation in response to insulin and glucagon-like peptide-1, as observed after RYGB. Obesity increased aortic phosphorylation of JNK2, but not of JNK1. RYGB and JNK peptide inhibitor D-JNKi-1 treatment blunted aortic JNK2 phosphorylation via activation of glucagon-like peptide-1-mediated signaling. The inhibitory phosphorylation of insulin receptor substrate-1 was reduced, whereas the protein kinase B/endothelial NO synthase pathway was increased and oxidative stress was decreased, resulting in improved vascular NO bioavailability. Decreased aortic JNK2 phosphorylation after RYGB rapidly improves obesity-induced endothelial dysfunction. Pharmacological JNK inhibition mimics the endothelial protective effects of RYGB. These findings highlight the therapeutic potential of novel strategies targeting vascular JNK2 against the severe cardiovascular disease associated with obesity. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Consuming a balanced high fat diet for 16 weeks improves body composition, inflammation and vascular function parameters in obese premenopausal women.

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Silver, Heidi J; Kang, Hakmook; Keil, Charles D; Muldowney, James A; Kocalis, Heidi; Fazio, Sergio; Vaughan, Douglas E; Niswender, Kevin D

2014-04-01

Inflammation, insulin resistance and vascular dysfunction characterize obesity and predict development of cardiovascular disease (CVD). Although women experience CVD events at an older age, vascular dysfunction is evident 10years prior to coronary artery disease. Questions remain whether replacing SFA entirely with MUFA or PUFA is the optimal approach for cardiometabolic benefits. This study tested the hypotheses that: a) body composition, inflammation and vascular function would improve with a high fat diet (HFD) when type of fat is balanced as 1/3 SFA, 1/3 MUFA and 1/3 PUFA; and b) body composition, inflammation and vascular function would improve more when balanced HFD is supplemented with 18C fatty acids, in proportion to the degree of 18C unsaturation. Obese premenopausal women were stabilized on balanced HFD and randomized to consume 9g/d of encapsulated stearate (18:0), oleate (18:1), linoleate (18:2) or placebo. Significant improvements occurred in fat oxidation rate (↑6%), body composition (%fat: ↓2.5±2.1%; %lean: ↑2.5±2.1%), inflammation (↓ IL-1α, IL-1β, 1L-12, Il-17, IFNγ, TNFα, TNFβ) and vascular function (↓BP, ↓PAI-1, ↑tPA activity). When compared to HFD+placebo, HFD+stearate had the greatest effect on reducing IFNγ (↓74%) and HFD+linoleate had the greatest effect on reducing PAI-1 (↓31%). Balancing the type of dietary fat consumed (SFA/MUFA/PUFA) is a feasible strategy to positively affect markers of CVD risk. Moreover, reductions in inflammatory molecules involved in vascular function might be enhanced when intake of certain 18C fatty acids is supplemented. Long term effects need to be determined for this approach. Copyright © 2014 Elsevier Inc. All rights reserved.

CONSUMING A BALANCED HIGH FAT DIET FOR 16 WEEKS IMPROVES BODY COMPOSITION, INFLAMMATION AND VASCULAR FUNCTION PARAMETERS IN OBESE PREMENOPAUSAL WOMEN

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Silver, Heidi J.; Kang, Hakmook; Keil, Charles D.; Muldowney, James A.; Kocalis, Heidi; Fazio, Sergio; Vaughan, Douglas E.; Niswender, Kevin D.

2014-01-01

Objective Inflammation, insulin resistance and vascular dysfunction characterize obesity and predict development of cardiovascular disease (CVD). Although women experience CVD events at an older age, vascular dysfunction is evident 10 years prior to coronary artery disease. Questions remain whether replacing SFA entirely with MUFA or PUFA is the optimal approach for cardiometabolic benefits. This study tested the hypotheses that: a) body composition, inflammation and vascular function would improve with a high fat diet (HFD) when type of fat is balanced as 1/3 SFA, 1/3 MUFA and 1/3 PUFA; and b) body composition, inflammation and vascular function would improve more when balanced HFD is supplemented with 18C fatty acids, in proportion to the degree of 18C unsaturation. Methods Obese premenopausal women were stabilized on balanced HFD and randomized to consume 9 g/d of encapsulated stearate (18:0), oleate (18:1), linoleate (18:2) or placebo. Results Significant improvements occurred in fat oxidation rate (↑6%), body composition (%fat: ↓2.5 ± 2.1%; %lean: ↑2.5 ± 2.1%), inflammation (↓ IL-1α, IL-1β, 1L-12, Il-17, IFNγ, TNFα, TNFβ) and vascular function (↓BP, ↓PAI-1, ↑tPA activity). When compared to HFD+placebo, HFD+stearate had the greatest effect on reducing IFNγ (↓74%) and HFD+linoleate had the greatest effect on reducing PAI-1 (↓31%). Conclusions Balancing the type of dietary fat consumed (SFA/MUFA/PUFA) is a feasible strategy to positively affect markers of CVD risk. Moreover, reductions in inflammatory molecules involved in vascular function might be enhanced when intake of certain 18C fatty acids is supplemented. Long term effects need to be determined for this approach. PMID:24559846

Vascular smooth muscle cells exhibit a progressive loss of rigidity with serial culture passaging.

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Dinardo, Carla Luana; Venturini, Gabriela; Omae, Samantha Vieira; Zhou, Enhua H; da Motta-Leal-Filho, Joaquim Maurício; Dariolli, Rafael; Krieger, José Eduardo; Alencar, Adriano Mesquita; Costa Pereira, Alexandre

2012-01-01

One drawback of in vitro cell culturing is the dedifferentiation process that cells experience. Smooth muscle cells (SMC) also change molecularly and morphologically with long term culture. The main objective of this study was to evaluate if culture passages interfere in vascular SMC mechanical behavior. SMC were obtained from five different porcine arterial beds. Optical magnetic twisting cytometry (OMTC) was used to characterize mechanically vascular SMC from different cultures in distinct passages and confocal microscopy/western blotting, to evaluate cytoskeleton and extracellular matrix proteins. We found that vascular SMC rigidity or viscoelastic complex modulus (G) decreases with progression of passages. A statistically significant negative correlation between G and passage was found in four of our five cultures studied. Phalloidin-stained SMC from higher passages exhibited lower mean signal intensity per cell (confocal microscopy) and quantitative western blotting analysis showed a decrease in collagen I content throughout passages. We concluded that vascular SMC progressively lose their stiffness with serial culture passaging. Thus, limiting the number of passages is essential for any experiment measuring viscoelastic properties of SMC in culture.

Vascular gastric anomalies as a cause of relapsing bleeding

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Golubović Gradimir

2008-01-01

Full Text Available Background. Although relatively rare, gastric vascular anomalies can be recognized as a source of both chronic and acute blood loss, most often presenting as long term iron deficiency anemia, rarely as severe acute gastrointestinal bleeding. Case report. We present five patients with various gastric vascular anomalies, diagnosed during the year of 2003. in the Clinical Hospital Center Zemun. The diagnosis was based on endoscopic appearances, clinical history and characteristic histological findings. Gastric vascular anomalies presented in our review were: portal hypertensive gastropathy, gastric antral vascular ectasia, angiodysplasia, hereditary hemorrhagic telangiectasia and Dieulafoy lesion. The used treatment modalities included surgery and various endoscopic techniques (schlerotherapy, argon plasma coagulation. Conclusion. Patients presented with chronic iron deficiency anemia or acute and recurrent gastrointestinal hemorrhage should be considered as having one of gastric vascular anomalies.

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

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Del Bo, Cristian; Riso, Patrizia; Campolo, Jonica

2013-01-01

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...

Engineering the mechanical and biological properties of nanofibrous vascular grafts for in situ vascular tissue engineering.

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Henry, Jeffrey J D; Yu, Jian; Wang, Aijun; Lee, Randall; Fang, Jun; Li, Song

2017-08-17

Synthetic small diameter vascular grafts have a high failure rate, and endothelialization is critical for preventing thrombosis and graft occlusion. A promising approach is in situ tissue engineering, whereby an acellular scaffold is implanted and provides stimulatory cues to guide the in situ remodeling into a functional blood vessel. An ideal scaffold should have sufficient binding sites for biomolecule immobilization and a mechanical property similar to native tissue. Here we developed a novel method to blend low molecular weight (LMW) elastic polymer during electrospinning process to increase conjugation sites and to improve the mechanical property of vascular grafts. LMW elastic polymer improved the elasticity of the scaffolds, and significantly increased the amount of heparin conjugated to the micro/nanofibrous scaffolds, which in turn increased the loading capacity of vascular endothelial growth factor (VEGF) and prolonged the release of VEGF. Vascular grafts were implanted into the carotid artery of rats to evaluate the in vivo performance. VEGF treatment significantly enhanced endothelium formation and the overall patency of vascular grafts. Heparin coating also increased cell infiltration into the electrospun grafts, thus increasing the production of collagen and elastin within the graft wall. This work demonstrates that LMW elastic polymer blending is an approach to engineer the mechanical and biological property of micro/nanofibrous vascular grafts for in situ vascular tissue engineering.

Connections matter: channeled hydrogels to improve vascularization

Directory of Open Access Journals (Sweden)

Severin eMuehleder

2014-11-01

Full Text Available The use of cell-laden hydrogels to engineer soft tissue has been emerging within the past years. Despite several newly developed and sophisticated techniques to encapsulate different cell types the importance of vascularization of the engineered constructs is often underestimated. As a result, cell death within a construct leads to impaired function and inclusion of the implant. Here, we discuss the fabrication of hollow channels within hydrogels as a promising strategy to facilitate vascularization. Furthermore, we present an overview on the feasible use of removable spacers, 3D laser- and planar processing strategies to create channels within hydrogels. The implementation of these structures promotes control over cell distribution and increases oxygen transport and nutrient supply in vitro. However, many studies lack the use of endothelial cells in their approaches leaving out an important factor to enhance vessel ingrowth and anastomosis formation upon implantation. In addition, the adequate endothelial cell type needs to be considered to make these approaches bridge the gap to in vivo applications.

B vitamins influence vascular cognitive impairment

Science.gov (United States)

As the number of elderly in the USA and globally continues to increase, age-related neurological disorders, such as Alzheimer's disease and vascular dementia, are a growing concern. The loss of memory, emotional changes, and impairments in general cognitive functioning frequently result in social is...

Improving MODPRESS heat loss calculations for PWR pressurizers

International Nuclear Information System (INIS)

Ramos, Natalia V.; Lira, Carlos A. Brayner O.; Castrillho, Lazara S.

2009-01-01

The improvement of heat loss calculations in MODPRESS transient code for PWR pressurizer analysis is the main focus of this investigation. Initially, a heat loss model was built based on heat transfer coefficient (HTC) correlations obtained in handbooks of thermal engineering. A hand calculation for Neptunus experimental test number U47 yielded a thermal power loss of 11.2 kW against 17.3 kW given by MODPRESS at the same conditions, while the experimental estimate is given as 17 kW. This comparison is valid only for steady state or before starting the transient experiment, because MODPRESS does not update HTC's when the transient phase begins. Furthermore, it must be noted that MODPRESS heat transfer coefficients are adjusted to reproduce the experimental value of the specific type of pressurizer. After inserting the new routine for HTC's into MODPRESS, the heat loss was calculated as 11.4 kW, a value very close to the first estimate but far below 17 kW found in the U47 experiment. In this paper, the heat loss model and results will be described. Further research is being developed to find a more general HTC that allows the analysis of the effects of heat losses on transient behavior of Neptunus and IRIS pressurizers. (author)

Radiation Retinopathy Is Treatable With Anti-Vascular Endothelial Growth Factor Bevacizumab (Avastin)

International Nuclear Information System (INIS)

Finger, Paul T.

2008-01-01

Purpose: To report on bevacizumab treatment for radiation retinopathy affecting the macula. Patients and Methods: Twenty-one patients with radiation retinopathy (edema, hemorrhages, capillary dropout, and neovascularization) and a subjective or objective loss of vision were treated. Treatment involved intravitreal injection of bevacizumab (1.25 mg in 0.05 mL) every 6-12 weeks. Treatment was discontinued at patient request or if there was no measurable response to therapy. Main outcome measures included best corrected visual acuity, ophthalmic examination, retinal photography, and angiography. Results: Bevacizumab treatment was followed by reductions in retinal hemorrhage, exudation, and edema. Visual acuities were stable or improved in 86% (n = 18). Three patients discontinued therapy. Each was legally blind before treatment (n = 1), experienced little to no subjective improvement (n = 2), or was poorly compliant (n = 2). Three patients (14%) regained 2 or more lines of visual acuity. No ocular or systemic bevacizumab-related side effects were observed. Conclusions: Intravitreal bevacizumab can be used to treat radiation retinopathy. In most cases treatment was associated with decreased vascular leakage, stabilization, or improved vision. An anti-vascular endothelial growth factor strategy may reduce tissue damage associated with radiation vasculopathy and neuropathy

Vascular Function Is Improved After an Environmental Enrichment Program: The Train the Brain-Mind the Vessel Study.

Science.gov (United States)

Bruno, Rosa Maria; Stea, Francesco; Sicari, Rosa; Ghiadoni, Lorenzo; Taddei, Stefano; Ungar, Andrea; Bonuccelli, Ubaldo; Tognoni, Gloria; Cintoli, Simona; Del Turco, Serena; Sbrana, Silverio; Gargani, Luna; D'Angelo, Gennaro; Pratali, Lorenza; Berardi, Nicoletta; Maffei, Lamberto; Picano, Eugenio

2018-06-01

Environmental enrichment may slow cognitive decay possibly acting through an improvement in vascular function. Aim of the study was to assess the effects of a 7-month cognitive, social, and physical training program on cognitive and vascular function in patients with mild cognitive impairment. In a single-center, randomized, parallel-group study, 113 patients (age, 65-89 years) were randomized to multidomain training (n=55) or usual care (n=58). All participants underwent neuropsychological tests and vascular evaluation, including brachial artery flow-mediated dilation, carotid-femoral pulse wave velocity, carotid distensibility, and assessment of circulating hematopoietic CD34+ and endothelial progenitor cells. At study entry, an age-matched control group (n=45) was also studied. Compared with controls, patients had at study entry a reduced flow-mediated dilation (2.97±2.14% versus 3.73±2.06%; P =0.03) and hyperemic stimulus (shear rate area under the curve, 19.1±15.7 versus 25.7±15.1×10 -3 ; P =0.009); only the latter remained significant after adjustment for confounders ( P =0.03). Training improved Alzheimer disease assessment scale cognitive (training, 14.0±4.8 to 13.1±5.5; nontraining, 12.1±3.9 to 13.2±4.8; P for interaction visit×training=0.02), flow-mediated dilation (2.82±2.19% to 3.40±1.81%, 3.05±2.08% to 2.24±1.59%; P =0.006; P =0.023 after adjustment for diameter and shear rate area under the curve), and circulating hematopoietic CD34 + cells and prevented the decline in carotid distensibility (18.4±5.3 to 20.0±6.6, 23.9±11.0 to 19.5±7.1 Pa -1 ; P =0.005). The only clinical predictor of improvement of cognitive function after training was established hypertension. There was no correlation between changes in measures of cognitive and vascular function. In conclusion, a multidomain training program slows cognitive decline, especially in hypertensive individuals. This effect is accompanied by improved systemic endothelial function

Improved Intratumoral Oxygenation Through Vascular Normalization Increases Glioma Sensitivity to Ionizing Radiation

International Nuclear Information System (INIS)

McGee, Mackenzie C.; Hamner, J. Blair; Williams, Regan F.; Rosati, Shannon F.; Sims, Thomas L.; Ng, Catherine Y.; Gaber, M. Waleed; Calabrese, Christopher; Wu Jianrong; Nathwani, Amit C.; Duntsch, Christopher; Merchant, Thomas E.; Davidoff, Andrew M.

2010-01-01

Purpose: Ionizing radiation, an important component of glioma therapy, is critically dependent on tumor oxygenation. However, gliomas are notable for areas of necrosis and hypoxia, which foster radioresistance. We hypothesized that pharmacologic manipulation of the typically dysfunctional tumor vasculature would improve intratumoral oxygenation and, thus, the antiglioma efficacy of ionizing radiation. Methods and Materials: Orthotopic U87 xenografts were treated with either continuous interferon-β (IFN-β) or bevacizumab, alone, or combined with cranial irradiation (RT). Tumor growth was assessed by quantitative bioluminescence imaging; the tumor vasculature using immunohistochemical staining, and tumor oxygenation using hypoxyprobe staining. Results: Both IFN-β and bevaziumab profoundly affected the tumor vasculature, albeit with different cellular phenotypes. IFN-β caused a doubling in the percentage of area of perivascular cell staining, and bevacizumab caused a rapid decrease in the percentage of area of endothelial cell staining. However, both agents increased intratumoral oxygenation, although with bevacizumab, the effect was transient, being lost by 5 days. Administration of IFN-β or bevacizumab before RT was significantly more effective than any of the three modalities as monotherapy or when RT was administered concomitantly with IFN-β or bevacizumab or 5 days after bevacizumab. Conclusion: Bevacizumab and continuous delivery of IFN-β each induced significant changes in glioma vascular physiology, improving intratumoral oxygenation and enhancing the antitumor activity of ionizing radiation. Additional investigation into the use and timing of these and other agents that modify the vascular phenotype, combined with RT, is warranted to optimize cytotoxic activity.

An improved iron loss estimation for permanent magnet brushless machines

CERN Document Server

Fang, D

1999-01-01

This paper presents an improved approach for predicting iron losses in permanent magnet brushless machines. The new approach is based on the fundamental concept that eddy current losses are proportional to the square of the time rate of change of flux density. Expressions are derived for predicting hysteresis and eddy current losses in the stator teeth and yoke. The so-called anomalous or excess losses, caused by the induced eddy current concentration around moving magnetic domain walls and neglected in the conventional core loss calculation, are also included in the proposed approach. In addition, the model is also capable of accounting for the stator skewing, if present. The core losses obtained from the proposed approach are compared with those measured on an existing PM motor at several operating speeds, showing very good agreement. (14 refs).

NF1 Signal Transduction and Vascular Dysfunction

Science.gov (United States)

2015-05-01

microenvironment that promotes much of the pathology associated with the disease . Moreover we hypothesize that a mechanistic consequence of the loss...obliteration of the normal red pulp architecture. In addition, we found significant peri-aveolar and peri-vascular inflammatory infiltrates in the lung...the mouse model of NF1 disease in the endothelium we proposed and have done experiments investigating the loss of endothelial NF1 in the adult

Using Polymeric Scaffolds for Vascular Tissue Engineering

Directory of Open Access Journals (Sweden)

Alida Abruzzo

2014-01-01

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

Improving PAGER's real-time earthquake casualty and loss estimation toolkit: a challenge

Science.gov (United States)

Jaiswal, K.S.; Wald, D.J.

2012-01-01

We describe the on-going developments of PAGER’s loss estimation models, and discuss value-added web content that can be generated related to exposure, damage and loss outputs for a variety of PAGER users. These developments include identifying vulnerable building types in any given area, estimating earthquake-induced damage and loss statistics by building type, and developing visualization aids that help locate areas of concern for improving post-earthquake response efforts. While detailed exposure and damage information is highly useful and desirable, significant improvements are still necessary in order to improve underlying building stock and vulnerability data at a global scale. Existing efforts with the GEM’s GED4GEM and GVC consortia will help achieve some of these objectives. This will benefit PAGER especially in regions where PAGER’s empirical model is less-well constrained; there, the semi-empirical and analytical models will provide robust estimates of damage and losses. Finally, we outline some of the challenges associated with rapid casualty and loss estimation that we experienced while responding to recent large earthquakes worldwide.

Using a phosphorus loss model to evaluate and improve phosphorus indices.

Science.gov (United States)

Bolster, Carl H; Vadas, Peter A; Sharpley, Andrew N; Lory, John A

2012-01-01

In most states, the phosphorus (P) index (PI) is the adopted strategy for assessing a field's vulnerability to P loss; however, many state PIs have not been rigorously evaluated against measured P loss data to determine how well the PI assigns P loss risk-a major reason being the lack of field data available for such an analysis. Given the lack of P loss data available for PI evaluation, our goal was to demonstrate how a P loss model can be used to evaluate and revise a PI using the Pennsylvania (PA) PI as an example. Our first objective was to compare two different formulations-multiplicative and component-for calculating a PI. Our second objective was to evaluate whether output from a P loss model can be used to improve PI weighting by calculating weights for modified versions of the PA PI from model-generated P loss data. Our results indicate that several potential limitations exist with the original multiplicative index formulation and that a component formulation is more consistent with how P loss is calculated with P loss models and generally provides more accurate estimates of P loss. Moreover, using the PI weights calculated from the model-generated data noticeably improved the correlation between PI values and a large and diverse measured P loss data set. The approach we use here can be used with any P loss model and PI and thus can serve as a guide to assist states in evaluating and modifying their PI. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Ftr82 Is Critical for Vascular Patterning during Zebrafish Development

Directory of Open Access Journals (Sweden)

Hsueh-Wei Chang

2017-01-01

Full Text Available Cellular components and signaling pathways are required for the proper growth of blood vessels. Here, we report for the first time that a teleost-specific gene ftr82 (finTRIM family, member 82 plays a critical role in vasculature during zebrafish development. To date, there has been no description of tripartite motif proteins (TRIM in vascular development, and the role of ftr82 is unknown. In this study, we found that ftr82 mRNA is expressed during the development of vessels, and loss of ftr82 by morpholino (MO knockdown impairs the growth of intersegmental vessels (ISV and caudal vein plexus (CVP, suggesting that ftr82 plays a critical role in promoting ISV and CVP growth. We showed the specificity of ftr82 MO by analyzing ftr82 expression products and expressing ftr82 mRNA to rescue ftr82 morphants. We further showed that the knockdown of ftr82 reduced ISV cell numbers, suggesting that the growth impairment of vessels is likely due to a decrease of cell proliferation and migration, but not cell death. In addition, loss of ftr82 affects the expression of vascular markers, which is consistent with the defect of vascular growth. Finally, we showed that ftr82 likely interacts with vascular endothelial growth factor (VEGF and Notch signaling. Together, we identify teleost-specific ftr82 as a vascular gene that plays an important role for vascular development in zebrafish.

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

Science.gov (United States)

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 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.

Disruption of COX-2 and eNOS does not confer protection from cardiovascular failure in lipopolysaccharide-treated conscious mice and isolated vascular rings

DEFF Research Database (Denmark)

Stæhr, Mette; Madsen, Kirsten; Vanhoutte, Paul M

2011-01-01

(NS 398), disruption of COX-2, endothelium removal, or eNOS deletion (eNOS(-/-)) did not improve vascular reactivity after LPS, while the NO synthase blockers 1400W and N(G)-nitro-l-arginine methyl ester prevented loss of tone. COX-2 and eNOS activities are not necessary for LPS-induced decreases...... in blood pressure, heart rate, and vascular reactivity. Inducible NOS activity appears crucial. COX-2 and eNOS are not obvious therapeutic targets for cardiovascular rescue during gram-negative endotoxemic shock....

Implementing clinical process management of vascular wounds in a tertiary facility: impact evaluation of a performance improvement project.

Science.gov (United States)

Avruscio, Giampiero; Tocco-Tussardi, Ilaria; Bordignon, Greta; Vindigni, Vincenzo

2017-01-01

Chronic vascular wounds have a significant economic and social impact on our society calling for allocation of a great deal of attention and resources. Efforts should be oriented toward the achievement of the most effective and efficient clinical management. The Angiology Unit at the University Hospital of Padova, Italy, developed a performance improvement project to enhance the quality of practice for vascular ulcers. The project consisted in a multistep process comprising a critical revision of the previous clinical process management, staff education, tightening connections between operators and services, and creation of a position for a wound care nurse. The previous standard of practice was modified according to the results of revision and the current evidence-based practice. The new standard of practice reached its full application in September 2015. The number of patients treated and the number of visits in 2015 remained almost unvaried from 2014. However, the total annual expenditure for treating vascular ulcers was reduced by ~60% from the previous year. Standardization of guidelines and practice is effective in creating an efficient clinical management and in reducing the economic burden of vascular ulcers.

Open and endovascular aneurysm repair in the Society for Vascular Surgery Vascular Quality Initiative.

Science.gov (United States)

Spangler, Emily L; Beck, Adam W

2017-12-01

The Society for Vascular Surgery Vascular Quality Initiative is a patient safety organization and a collection of procedure-based registries that can be utilized for quality improvement initiatives and clinical outcomes research. The Vascular Quality Initiative consists of voluntary participation by centers to collect data prospectively on all consecutive cases within specific registries which physicians and centers elect to participate. The data capture extends from preoperative demographics and risk factors (including indications for operation), through the perioperative period, to outcomes data at up to 1-year of follow-up. Additionally, longer-term follow-up can be achieved by matching with Medicare claims data, providing long-term longitudinal follow-up for a majority of patients within the Vascular Quality Initiative registries. We present the unique characteristics of the Vascular Quality Initiative registries and highlight important insights gained specific to open and endovascular abdominal aortic aneurysm repair. Copyright © 2017 Elsevier Inc. All rights reserved.

Estrogen, vascular estrogen receptor and hormone therapy in postmenopausal vascular disease.

Science.gov (United States)

Khalil, Raouf A

2013-12-15

Cardiovascular disease (CVD) is less common in premenopausal women than men of the same age or postmenopausal women, suggesting vascular benefits of estrogen. Estrogen activates estrogen receptors ERα, ERβ and GPR30 in endothelium and vascular smooth muscle (VSM), which trigger downstream signaling pathways and lead to genomic and non-genomic vascular effects such as vasodilation, decreased VSM contraction and growth and reduced vascular remodeling. However, randomized clinical trials (RCTs), such as the Women's Health Initiative (WHI) and Heart and Estrogen/progestin Replacement Study (HERS), have shown little vascular benefits and even adverse events with menopausal hormone therapy (MHT), likely due to factors related to the MHT used, ER profile, and RCT design. Some MHT forms, dose, combinations or route of administration may have inadequate vascular effects. Age-related changes in ER amount, distribution, integrity and post-ER signaling could alter the vascular response to MHT. The subject's age, preexisting CVD, and hormone environment could also reduce the effects of MHT. Further evaluation of natural and synthetic estrogens, phytoestrogens, and selective estrogen-receptor modulators (SERMs), and the design of appropriate MHT combinations, dose, route and 'timing' could improve the effectiveness of conventional MHT and provide alternative therapies in the peri-menopausal period. Targeting ER using specific ER agonists, localized MHT delivery, and activation of specific post-ER signaling pathways could counter age-related changes in ER. Examination of the hormone environment and conditions associated with hormone imbalance such as polycystic ovary syndrome may reveal the causes of abnormal hormone-receptor interactions. Consideration of these factors in new RCTs such as the Kronos Early Estrogen Prevention Study (KEEPS) could enhance the vascular benefits of estrogen in postmenopausal CVD. Copyright © 2013 Elsevier Inc. All rights reserved.

Adherence to a behavioral weight loss treatment program enhances weight loss and improvements in biomarkers

Directory of Open Access Journals (Sweden)

Sushama D Acharya

2009-06-01

treatment component as the intervention intensity was reduced. Adherence to multiple treatment components was associated with greater weight loss and improvements in biomarkers. Future research needs to focus on improving and maintaining adherence to all components of the treatment protocol to promote weight loss and maintenance.Keywords: adherence, obesity, diet, exercise, self-monitoring, biomarkers

Does Successful Weight Loss in an Internet-Based Worksite Weight Loss Program Improve Employee Presenteeism and Absenteeism?

Science.gov (United States)

Harden, Samantha M.; You, Wen; Almeida, Fabio A.; Hill, Jennie L.; Linnan, Laura A.; Allen, Kacie C.; Estabrooks, Paul A.

2017-01-01

Certain risk factors associated with overweight and obesity may lead to reduced productivity in the workforce (i.e., increased absenteeism and presenteeism). Participants in a large, Internet-based worksite weight loss intervention, who were present at follow-up (N = 1,030), completed a self-reported productivity measure (World Health Organization’s Health and Work Performance Questionnaire) at baseline and postintervention. Twenty-two percent of the participants lost a clinically meaningful amount of weight (≥5% weight loss). There were no statistically significant (p absenteeism or for absolute or relative presenteeism. Within a modestly successful Internet-based, worksite weight loss intervention, weight loss did not improve self-reported absenteeism or presenteeism. Further studies are needed to explore the sensitivity of the World Health Organization’s Health and Work Performance Questionnaire and the long-term effects of weight loss on productivity. PMID:25842385

Hibernation Based Therapy to Improve Survival of Severe Blood Loss

Science.gov (United States)

2016-06-01

leaks extravascularly • Necrosis and inflammation involving the ear tip is considered to be a more severe manifestation of vascular damage associated...similar lesions to the 2M test solution, it appears that 2M test solution is more likely to cause vascular necrosis and inflammation (noted at 24 hours...injections • Although DMSO induced similar lesions to the 4M test solution, it appears that 4M test solution is more likely to cause vascular necrosis and

Implementing clinical process management of vascular wounds in a tertiary facility: impact evaluation of a performance improvement project

Directory of Open Access Journals (Sweden)

Avruscio G

2017-10-01

Full Text Available Giampiero Avruscio,1,* Ilaria Tocco-Tussardi,1,2,* Greta Bordignon,3 Vincenzo Vindigni2 1Angiology Unit, Department of Cardiac, Thoracic and Vascular Sciences, University Hospital of Padova, Padova, Italy; 2Clinic of Plastic and Reconstructive Surgery, Department of Neurosciences, University Hospital of Padova, Padova, Italy; 3Clinical Management, University Hospital of Padova, Padova, Italy *These authors contributed equally to this work Background: Chronic vascular wounds have a significant economic and social impact on our society calling for allocation of a great deal of attention and resources. Efforts should be oriented toward the achievement of the most effective and efficient clinical management. The Angiology Unit at the University Hospital of Padova, Italy, developed a performance improvement project to enhance the quality of practice for vascular ulcers.Methods: The project consisted in a multistep process comprising a critical revision of the previous clinical process management, staff education, tightening connections between operators and services, and creation of a position for a wound care nurse. The previous standard of practice was modified according to the results of revision and the current evidence-based practice.Results: The new standard of practice reached its full application in September 2015. The number of patients treated and the number of visits in 2015 remained almost unvaried from 2014. However, the total annual expenditure for treating vascular ulcers was reduced by ~60% from the previous year.Conclusion: Standardization of guidelines and practice is effective in creating an efficient clinical management and in reducing the economic burden of vascular ulcers. Keywords: chronic wounds, clinical process management, cost-effectiveness, vascular ulcers

Does Successful Weight Loss in an Internet-Based Worksite Weight Loss Program Improve Employee Presenteeism and Absenteeism?

Science.gov (United States)

Harden, Samantha M; You, Wen; Almeida, Fabio A; Hill, Jennie L; Linnan, Laura A; Allen, Kacie C; Estabrooks, Paul A

2015-12-01

Certain risk factors associated with overweight and obesity may lead to reduced productivity in the workforce (i.e., increased absenteeism and presenteeism). Participants in a large, Internet-based worksite weight loss intervention, who were present at follow-up (N = 1,030), completed a self-reported productivity measure (World Health Organization's Health and Work Performance Questionnaire) at baseline and postintervention. Twenty-two percent of the participants lost a clinically meaningful amount of weight (≥5% weight loss). There were no statistically significant (p absenteeism or for absolute or relative presenteeism. Within a modestly successful Internet-based, worksite weight loss intervention, weight loss did not improve self-reported absenteeism or presenteeism. Further studies are needed to explore the sensitivity of the World Health Organization's Health and Work Performance Questionnaire and the long-term effects of weight loss on productivity. © 2015 Society for Public Health Education.

Sirtuins, Cell Senescence, and Vascular Aging.

Science.gov (United States)

Kida, Yujiro; Goligorsky, Michael S

2016-05-01

The sirtuins (SIRTs) constitute a class of proteins with nicotinamide adenine dinucleotide-dependent deacetylase or adenosine diphosphate-ribosyltransferase activity. Seven SIRT family members have been identified in mammals, from SIRT1, the best studied for its role in vascular aging, to SIRT7. SIRT1 and SIRT2 are localized in the nucleus and cytoplasm. SIRT3, SIRT4, and SIRT5 are mitochondrial, and SIRT6 and SIRT7 are nuclear. Extensive studies have clearly revealed that SIRT proteins regulate diverse cell functions and responses to stressors. Vascular aging involves the aging process (senescence) of endothelial and vascular smooth muscle cells. Two types of cell senescence have been identified: (1) replicative senescence with telomere attrition; and (2) stress-induced premature senescence without telomere involvement. Both types of senescence induce vascular cell growth arrest and loss of vascular homeostasis, and contribute to the initiation and progression of cardiovascular diseases. Previous mechanistic studies have revealed in detail that SIRT1, SIRT3, and SIRT6 show protective functions against vascular aging, and definite vascular function of other SIRTs is under investigation. Thus, direct SIRT modulation and nicotinamide adenine dinucleotide stimulation of SIRT are promising candidates for cardiovascular disease therapy. A small number of pilot studies have been conducted to assess SIRT modulation in humans. These clinical studies have not yet provided convincing evidence that SIRT proteins alleviate morbidity and mortality in patients with cardiovascular diseases. The outcomes of multiple ongoing clinical trials are awaited to define the efficacy of SIRT modulators and SIRT activators in cardiovascular diseases, along with the potential adverse effects of chronic SIRT modulation. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Hurricane Loss Estimation Models: Opportunities for Improving the State of the Art.

Science.gov (United States)

Watson, Charles C., Jr.; Johnson, Mark E.

2004-11-01

The results of hurricane loss models are used regularly for multibillion dollar decisions in the insurance and financial services industries. These models are proprietary, and this “black box” nature hinders analysis. The proprietary models produce a wide range of results, often producing loss costs that differ by a ratio of three to one or more. In a study for the state of North Carolina, 324 combinations of loss models were analyzed, based on a combination of nine wind models, four surface friction models, and nine damage models drawn from the published literature in insurance, engineering, and meteorology. These combinations were tested against reported losses from Hurricanes Hugo and Andrew as reported by a major insurance company, as well as storm total losses for additional storms. Annual loss costs were then computed using these 324 combinations of models for both North Carolina and Florida, and compared with publicly available proprietary model results in Florida. The wide range of resulting loss costs for open, scientifically defensible models that perform well against observed losses mirrors the wide range of loss costs computed by the proprietary models currently in use. This outcome may be discouraging for governmental and corporate decision makers relying on this data for policy and investment guidance (due to the high variability across model results), but it also provides guidance for the efforts of future investigations to improve loss models. Although hurricane loss models are true multidisciplinary efforts, involving meteorology, engineering, statistics, and actuarial sciences, the field of meteorology offers the most promising opportunities for improvement of the state of the art.

Contemporary vascular smartphone medical applications.

Science.gov (United States)

Carter, Thomas; O'Neill, Stephen; Johns, Neil; Brady, Richard R W

2013-08-01

Use of smartphones and medical mHealth applications (apps) within the clinical environment provides a potential means for delivering elements of vascular care. This article reviews the contemporary availability of apps specifically themed to major vascular diseases and the opportunities and concerns regarding their integration into practice. Smartphone apps relating to major vascular diseases were identified from the app stores for the 6 most popular smartphone platforms, including iPhone, Android, Blackberry, Nokia, Windows, and Samsung. Search terms included peripheral artery (arterial) disease, varicose veins, aortic aneurysm, carotid artery disease, amputation, ulcers, hyperhydrosis, thoracic outlet syndrome, vascular malformation, and lymphatic disorders. Forty-nine vascular-themed apps were identified. Sixteen (33%) were free of charge. Fifteen apps (31%) had customer satisfaction ratings, but only 3 (6%) had greater than 100. Only 13 apps (27%) had documented medical professional involvement in their design or content. The integration of apps into the delivery of care has the potential to benefit vascular health care workers and patients. However, high-quality apps designed by clinicians with vascular expertise are currently lacking and represent an area of concern in the mHealth market. Improvement in the quality and reliability of these apps will require the development of robust regulation. Copyright © 2013 Elsevier Inc. All rights reserved.

The vascular basement membrane in the healthy and pathological brain.

Science.gov (United States)

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.

Biomaterial-mediated strategies targeting vascularization for bone repair.

Science.gov (United States)

García, José R; García, Andrés J

2016-04-01

Repair of non-healing bone defects through tissue engineering strategies remains a challenging feat in the clinic due to the aversive microenvironment surrounding the injured tissue. The vascular damage that occurs following a bone injury causes extreme ischemia and a loss of circulating cells that contribute to regeneration. Tissue-engineered constructs aimed at regenerating the injured bone suffer from complications based on the slow progression of endogenous vascular repair and often fail at bridging the bone defect. To that end, various strategies have been explored to increase blood vessel regeneration within defects to facilitate both tissue-engineered and natural repair processes. Developments that induce robust vascularization will need to consolidate various parameters including optimization of embedded therapeutics, scaffold characteristics, and successful integration between the construct and the biological tissue. This review provides an overview of current strategies as well as new developments in engineering biomaterials to induce reparation of a functional vascular supply in the context of bone repair.

Transforming growth factor β family members in regulation of vascular function: in the light of vascular conditional knockouts.

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Jakobsson, Lars; van Meeteren, Laurens A

2013-05-15

Blood vessels are composed of endothelial cells, mural cells (smooth muscle cells and pericytes) and their shared basement membrane. During embryonic development a multitude of signaling components orchestrate the formation of new vessels. The process is highly dependent on correct dosage, spacing and timing of these signaling molecules. As vessels mature some cascades remain active, albeit at very low levels, and may be reactivated upon demand. Members of the Transforming growth factor β (TGF-β) protein family are strongly engaged in developmental angiogenesis but are also regulators of vascular integrity in the adult. In humans various genetic alterations within this protein family cause vascular disorders, involving disintegration of vascular integrity. Here we summarize and discuss recent data gathered from conditional and endothelial cell specific genetic loss-of-function of members of the TGF-β family in the mouse. Copyright © 2013 Elsevier Inc. All rights reserved.

Nutritional improvement of the endothelial control of vascular tone by polyphenols: role of NO and EDHF.

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Schini-Kerth, Valérie B; Auger, Cyril; Kim, Jong-Hun; Etienne-Selloum, Nelly; Chataigneau, Thierry

2010-05-01

Numerous studies indicate that regular intake of polyphenol-rich beverages (red wine and tea) and foods (chocolate, fruit, and vegetables) is associated with a protective effect on the cardiovascular system in humans and animals. Beyond the well-known antioxidant properties of polyphenols, several other mechanisms have been shown to contribute to their beneficial cardiovascular effects. Indeed, both experimental and clinical studies indicate that polyphenols improve the ability of endothelial cells to control vascular tone. Experiments with isolated arteries have shown that polyphenols cause nitric oxide (NO)-mediated endothelium-dependent relaxations and increase the endothelial formation of NO. The polyphenol-induced NO formation is due to the redox-sensitive activation of the phosphatidylinositol3-kinase/Akt pathway leading to endothelial NO synthase (eNOS) activation subsequent to its phosphorylation on Ser 1177. Besides the phosphatidylinositol3-kinase/Akt pathway, polyphenols have also been shown to activate eNOS by increasing the intracellular free calcium concentration and by activating estrogen receptors in endothelial cells. In addition to causing a rapid and sustained activation of eNOS by phosphorylation, polyphenols can increase the expression level of eNOS in endothelial cells leading to an increased formation of NO. Moreover, the polyphenol-induced endothelium-dependent relaxation also involves endothelium-derived hyperpolarizing factor, besides NO, in several types of arteries. Altogether, polyphenols have the capacity to improve the endothelial control of vascular tone not only in several experimental models of cardiovascular diseases such as hypertension but also in healthy and diseased humans. Thus, these experimental and clinical studies highlight the potential of polyphenol-rich sources to provide vascular protection in health and disease.

The fractionation of adipose tissue procedure to obtain stromal vascular fractions for regenerative purposes

NARCIS (Netherlands)

van Dongen, Joris A.; Stevens, Hieronymus P.; Parvizi, Mojtaba; van der Lei, Berend; Harmsen, Martin C.

2016-01-01

Autologous adipose tissue transplantation is clinically used to reduce dermal scarring and to restore volume loss. The therapeutic benefit on tissue damage more likely depends on the stromal vascular fraction of adipose tissue than on the adipocyte fraction. This stromal vascular fraction can be

Extracellular Matrix Molecules Facilitating Vascular Biointegration

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Martin K.C. Ng

2012-08-01

Full Text Available All vascular implants, including stents, heart valves and graft materials exhibit suboptimal biocompatibility that significantly reduces their clinical efficacy. A range of biomolecules in the subendothelial space have been shown to play critical roles in local regulation of thrombosis, endothelial growth and smooth muscle cell proliferation, making these attractive candidates for modulation of vascular device biointegration. However, classically used biomaterial coatings, such as fibronectin and laminin, modulate only one of these components; enhancing endothelial cell attachment, but also activating platelets and triggering thrombosis. This review examines a subset of extracellular matrix molecules that have demonstrated multi-faceted vascular compatibility and accordingly are promising candidates to improve the biointegration of vascular biomaterials.

Selective cyclooxygenase-1 inhibition improves collateral vascular reactivity in biliary cirrhotic rats

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Ching-Chih Chang

2013-10-01

Conclusion: There was no significant hemodynamic change and renal toxicity after acute administration of COX inhibitor in the FBDL-induced cirrhotic rats. Preincubation of selective COX-1, but not COX-2, inhibitor could enhance collateral vascular response to AVP, indicating that COX-1 plays a major role in the collateral vascular reactivity.

Vascular Endothelial Growth Factor Improves Physico-Mechanical Properties and Enhances Endothelialization of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/Poly(ε-caprolactone) Small-Diameter Vascular Grafts In vivo.

Science.gov (United States)

Antonova, Larisa V; Sevostyanova, Victoria V; Kutikhin, Anton G; Mironov, Andrey V; Krivkina, Evgeniya O; Shabaev, Amin R; Matveeva, Vera G; Velikanova, Elena A; Sergeeva, Evgeniya A; Burago, Andrey Y; Vasyukov, Georgiy Y; Glushkova, Tatiana V; Kudryavtseva, Yuliya A; Barbarash, Olga L; Barbarash, Leonid S

2016-01-01

The combination of a natural polymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and a synthetic hydrophobic polymer poly(ε-caprolactone) (PCL) is promising for the preparation of biodegradable and biocompatible small-diameter vascular grafts for bypass surgery. However, physico-mechanical properties and endothelialization rate of PHBV/PCL grafts are poor. We suggested that incorporation of vascular endothelial growth factor (VEGF) into PHBV/PCL grafts may improve their physico-mechanical properties and enhance endothelialization. Here we compared morphology, physico-mechanical properties, and in vivo performance of electrospun small-diameter vascular grafts prepared from PHBV/PCL with and without VEGF. Structure of the graft surface and physico-mechanical properties were examined by scanning electron microscopy and universal testing machine, respectively. Grafts were implanted into rat abdominal aorta for 1, 3, and 6 months with the further histological, immunohistochemical, and immunofluorescence examination. PHBV/PCL grafts with and without VEGF were highly porous and consisted mostly of nanoscale and microscale fibers, respectively. Mean pore diameter and mean pore area were significantly lower in PHBV/PCL/VEGF compared to PHBV/PCL grafts (1.47 μm and 10.05 μm(2); 2.63 μm and 47.13 μm(2), respectively). Durability, elasticity, and stiffness of PHBV/PCL grafts with VEGF were more similar to internal mammary artery compared to those without, particularly 6 months postimplantation. Both qualitative examination and quantitative image analysis showed that three-fourths of PHBV/PCL grafts with VEGF were patent and had many CD31-, CD34-, and vWF-positive cells at their inner surface. However, all PHBV/PCL grafts without VEGF were occluded and had no or a few CD31-positive cells at the inner surface. Therefore, VEGF enhanced endothelialization and improved graft patency at all the time points in a rat abdominal aorta replacement model. In conclusion, PHBV

Banding the Sleeve Improves Weight Loss in Midterm Follow-up.

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Fink, Jodok M; Hoffmann, Natalie; Kuesters, Simon; Seifert, Gabriel; Laessle, Claudia; Glatz, Torben; Hopt, Ulrich T; Konrad Karcz, W; Marjanovic, Goran

2017-04-01

Laparoscopic sleeve gastrectomy (LSG) can achieve excellent weight loss, yet sleeve dilatation with concomitant weight regain proves to be a relevant issue. Hence, additional restriction might improve results after LSG. In a retrospective matched-pair analysis, 42 patients who underwent banded LSG (BLSG) using a MiniMizer® ring between January 2012 and October 2014 were analysed regarding weight loss, complications and comorbidity. Median follow-up was 3 years. Forty-two patients who had undergone conventional LSG were selected as matched pairs. Mean preoperative BMI was 54.93 ± 7.42 kg/m 2 for BLSG and 53.46 ± 6.69 kg/m 2 for LSG (Mann-Whitney P = 0.540). Total weight loss (%TWL) was significantly greater in the BLSG group 3 years after surgery (BLSG 38.22% ± 7.26; n = 26 vs. LSG 32.69 ± 9.47; n = 26; P = 0.0154). Ring placement had no relevant impact on new-onset reflux (Fisher's exact test P = 1.0) but a tendency towards reflux improvement when reflux pre-existed (odds ratio 1.96). The major side effect of ring implantation was regurgitation with over 44% of patients presenting with regurgitation >1 per week (Fisher's exact test P = 0.0019, odds ratio 18.07). BLSG is a safe procedure showing similar comorbidity to conventional LSG. However, BLSG leads to a higher rate of postoperative regurgitation. Weight loss is significantly improved 3 years after surgery. Hence, additional ring implantation might be an option for increased restriction in LSG surgery.

Habitat-based conservation strategies cannot compensate for climate-change-induced range loss

Science.gov (United States)

Wessely, Johannes; Hülber, Karl; Gattringer, Andreas; Kuttner, Michael; Moser, Dietmar; Rabitsch, Wolfgang; Schindler, Stefan; Dullinger, Stefan; Essl, Franz

2017-11-01

Anthropogenic habitat fragmentation represents a major obstacle to species shifting their range in response to climate change. Conservation measures to increase the (meta-)population capacity and permeability of landscapes may help but the effectiveness of such measures in a warming climate has rarely been evaluated. Here, we simulate range dynamics of 51 species from three taxonomic groups (vascular plants, butterflies and grasshoppers) in Central Europe as driven by twenty-first-century climate scenarios and analyse how three habitat-based conservation strategies (establishing corridors, improving the landscape matrix, and protected area management) modify species' projected range size changes. These simulations suggest that the conservation strategies considered are unable to save species from regional extinction. For those persisting, they reduce the magnitude of range loss in lowland but not in alpine species. Protected area management and corridor establishment are more effective than matrix improvement. However, none of the conservation strategies evaluated could fully compensate the negative impact of climate change for vascular plants, butterflies or grasshoppers in central Europe.

Influence of Androgen Receptor in Vascular Cells on Reperfusion following Hindlimb Ischaemia.

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Junxi Wu

Full Text Available Studies in global androgen receptor knockout (G-ARKO and orchidectomised mice suggest that androgen accelerates reperfusion of the ischaemic hindlimb by stimulating angiogenesis. This investigation used novel, vascular cell-specific ARKO mice to address the hypothesis that the impaired hindlimb reperfusion in G-ARKO mice was due to loss of AR from cells in the vascular wall.Mice with selective deletion of AR (ARKO from vascular smooth muscle cells (SM-ARKO, endothelial cells (VE-ARKO, or both (SM/VE-ARKO were compared with wild type (WT controls. Hindlimb ischaemia was induced in these mice by ligation and removal of the femoral artery. Post-operative reperfusion was reduced in SM-ARKO and SM/VE-ARKO mice. Immunohistochemistry indicated that this was accompanied by a reduced density of smooth muscle actin-positive vessels but no change in the density of isolectin B4-positive vessels in the gastrocnemius muscle. Deletion of AR from the endothelium (VE-ARKO did not alter post-operative reperfusion or vessel density. In an ex vivo (aortic ring culture model of angiogenesis, AR was not detected in vascular outgrowths and angiogenesis was not altered by vascular ARKO or by exposure to dihydrotestosterone (DHT 10-10-10-7M; 6 days.These results suggest that loss of AR from vascular smooth muscle, but not from the endothelium, contributes to impaired reperfusion in the ischaemic hindlimb of G-ARKO. Impaired reperfusion was associated with reduced collateral formation rather than reduced angiogenesis.

Longitudinal visualization of vascular occlusion, reperfusion, and remodeling in a zebrafish model of retinal vascular leakage using OCT angiography

Science.gov (United States)

Spitz, Kathleen; Bozic, Ivan; Desai, Vineet; Rao, Gopikrishna M.; Pollock, Lana M.; Anand-Apte, Bela; Tao, Yuankai K.

2017-02-01

Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are two of the leading causes of blindness and visual impairment in the world. Neovascularization results in severe vision loss in DR and AMD and, thus, there is an unmet need to identify mechanisms of pathogenesis and novel anti-angiogenic therapies. Zebrafish is a leading model organism for studying human disease pathogenesis, and the highly conserved drug activity between zebrafish and humans and their ability to readily absorb small molecules dissolved in water has benefited pharmaceutical discovery. Here, we use optical coherence tomography (OCT) and OCT angiography (OCT-A) to perform noninvasive, in vivo retinal imaging in a zebrafish model of vascular leakage. Zebrafish were treated with diethylaminobenzaldehyde (DEAB) to induce vascular leakage and imaged with OCT and OCT-A at six time points over two weeks: baseline one day before treatment and one, three, six, eight, and ten days post treatment. Longitudinal functional imaging showed significant vascular response immediately after DEAB treatment. Observed vascular changes included partial or complete vascular occlusion immediately after treatment and reperfusion during a two-week period. Increased vascular tortuosity several days post treatment indicated remodeling, and bifurcations and collateral vessel formation were also observed. In addition, significant treatment response variabilities were observed in the contralateral eye of the same animal. Anatomical and functional normalization was observed in most animals by ten days post treatment. These preliminary results motivate potential applications of OCT-A as a tool for studying pathogenesis and therapeutic screening in zebrafish models of retinal vascular disease.

Ebselen does not improve oxidative stress and vascular function in patients with diabetes: a randomized, crossover trial.

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Beckman, Joshua A; Goldfine, Allison B; Leopold, Jane A; Creager, Mark A

2016-12-01

Oxidative stress is a key driver of vascular dysfunction in diabetes mellitus. Ebselen is a glutathione peroxidase mimetic. A single-site, randomized, double-masked, placebo-controlled, crossover trial was carried out in 26 patients with type 1 or type 2 diabetes to evaluate effects of high-dose ebselen (150 mg po twice daily) administration on oxidative stress and endothelium-dependent vasodilation. Treatment periods were in random order of 4 wk duration, with a 4-wk washout between treatments. Measures of oxidative stress included nitrotyrosine, plasma 8-isoprostanes, and the ratio of reduced to oxidized glutathione. Vascular ultrasound of the brachial artery and plethysmographic measurement of blood flow were used to assess flow-mediated and methacholine-induced endothelium-dependent vasodilation of conduit and resistance vessels, respectively. Ebselen administration did not affect parameters of oxidative stress or conduit artery or forearm arteriolar vascular function compared with placebo treatment. There was no difference in outcome by diabetes type. Ebselen, at the dose and duration evaluated, does not improve the oxidative stress profile, nor does it affect endothelium-dependent vasodilation in patients with diabetes mellitus. Copyright © 2016 the American Physiological Society.

ON SOME IDEAS FOR IMPROVEMENT OF IDENTIFICATION AND RECORDING GAINS/LOSSES

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Jaan Alver

2016-09-01

Full Text Available The aim of paper is to analyze the definitions and recording process of revenues and gains. The authors of current paper have worked out some suggestions for improving the reporting process taking into account the definitions of income, revenue, gains, losses and profit. Analyzing the inconsistency in two pairs of opposite terms (Profit and Loss and Gain and Loss the authors came to conclusion that the amount named gain/loss in disposal of property, plant and equipment is rather correction or adjustment of previous miscalculation of depreciation expense due to the formula. To make aforementioned adjustments and show them separately a Contra depreciation expense account or Depreciation adjunct account is recommended.

Bioprinting for vascular and vascularized tissue biofabrication.

Science.gov (United States)

Datta, Pallab; Ayan, Bugra; Ozbolat, Ibrahim T

2017-03-15

Bioprinting is a promising technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision. Bioprinting enables the deposition of various biologics including growth factors, cells, genes, neo-tissues and extra-cellular matrix-like hydrogels. Benefits of bioprinting have started to make a mark in the fields of tissue engineering, regenerative medicine and pharmaceutics. Specifically, in the field of tissue engineering, the creation of vascularized tissue constructs has remained a principal challenge till date. However, given the myriad advantages over other biofabrication methods, it becomes organic to expect that bioprinting can provide a viable solution for the vascularization problem, and facilitate the clinical translation of tissue engineered constructs. This article provides a comprehensive account of bioprinting of vascular and vascularized tissue constructs. The review is structured as introducing the scope of bioprinting in tissue engineering applications, key vascular anatomical features and then a thorough coverage of 3D bioprinting using extrusion-, droplet- and laser-based bioprinting for fabrication of vascular tissue constructs. The review then provides the reader with the use of bioprinting for obtaining thick vascularized tissues using sacrificial bioink materials. Current challenges are discussed, a comparative evaluation of different bioprinting modalities is presented and future prospects are provided to the reader. Biofabrication of living tissues and organs at the clinically-relevant volumes vitally depends on the integration of vascular network. Despite the great progress in traditional biofabrication approaches, building perfusable hierarchical vascular network is a major challenge. Bioprinting is an emerging technology to fabricate design-specific tissue constructs due to its ability to create complex, heterocellular structures with anatomical precision

Age related vascular endothelial function following lifelong sedentariness: positive impact of cardiovascular conditioning without further improvement following low frequency high intensity interval training

OpenAIRE

Grace, Fergal M.; Herbert, Peter; Ratcliffe, John W.; New, Karl J.; Baker, Julien S.; Sculthorpe, Nicholas F.

2015-01-01

Abstract Aging is associated with diffuse impairments in vascular endothelial function and traditional aerobic exercise is known to ameliorate these changes. High intensity interval training (HIIT) is effective at improving vascular function in aging men with existing disease, but its effectiveness remains to be demonstrated in otherwise healthy sedentary aging. However, the frequency of commonly used HIIT protocols may be poorly tolerated in older cohorts. Therefore, the present study invest...

[Can the vascular specialist improve patient awareness about advanced directives?].

Science.gov (United States)

Sanson, H; Priollet, P

2016-05-01

In France, the Leonetti law, adopted on April 22, 2005, stipulates the regulations concerning advanced directives. This is a patient's right that is not well known and rarely applied. In 2015, a new law project was thus presented in which the French National Authority for Health recommended that doctors, including all specialists, bring up the subject, especially during consultation. To evaluate the vascular specialist's possibility to mention the topic of advanced directives during consultations. A single and non-interventional prospective study conducted with the help of patients who consulted a private practitioner vascular specialist: recurrent patients regularly consulting a private practitioner vascular specialist were included. First-time consultants, minors and patients to whom it was not adapted to speak about the subject were not included. Between July 27 and September 23, 2015, 159 consecutive patients were examined. Fifty-five first-time consultants and four patients for whom the interview was unsuitable were excluded. In all, 100 patients were questioned. None of them refused to talk about the subject. Women made up a majority of the population (63 %) with an average age of 67 years (23-97). The principal diagnostics were common to vascular medicine consultations: deep vein thrombosis (20 %), peripheral arterial disease (15 %), varicose veins (11 %), lymphedema (11 %) and leg ulcers (9 %). Thirteen percent of the people had a history of cancer. Half of the patients had had follow-ups for over 10 years. The average time devoted to discussing the topic was 12minutes (5-40). Only 22 % of the patients declared having been familiar with advance directives. Once informed however, 78 % chose to write up an adapted form: 36 % with the help of their doctor and 42 % with a doctor and a relative. Seventy-three percent of the consultants thought that talking about the advance directives would reinforce the confidence link between the doctor and the

Vascular risk factors, cognitve decline, and dementia

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E Duron

2008-04-01

Full Text Available E Duron, Olivier HanonBroca Hospital, Paris, FranceAbstract: Dementia is one of the most important neurological disorders in the elderly. Aging is associated with a large increase in the prevalence and incidence of degenerative (Alzheimer’s disease and vascular dementia, leading to a devastating loss of autonomy. In view of the increasing longevity of populations worldwide, prevention of dementia has turned into a major public health challenge. In the past decade, several vascular risk factors have been found to be associated with vascular dementia but also Alzheimer’s disease. Some longitudinal studies, have found significant associations between hypertension, diabetus mellitus, and metabolic syndrome, assessed at middle age, and dementia. Studies assessing the link between hypercholesterolemia, atrial fibrillation, smoking, and dementia have given more conflicting results. Furthermore, some studies have highlighted the possible protective effect of antihypertensive therapy on cognition and some trials are evaluating the effects of statins and treatments for insulin resistance. Vascular risk factors and their treatments are a promising avenue of research for prevention of dementia, and further long-term, placebo-controlled, randomized studies, need to be performed.Keywords: dementia, hypertension, diabetus mellitus, hypercholesterolemia, metabolic syndrome

Improved FPGA controlled artificial vascular system for plethysmographic measurements

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Laqua Daniel

2016-09-01

Full Text Available The fetal oxygen saturation is an important parameter to determine the health status of a fetus, which is until now mostly acquired invasively. The transabdominal, fetal pulse oximetry is a promising approach to measure this non-invasively and continuously. The fetal pulse curve has to be extracted from the mixed signal of mother and fetus to determine its oxygen saturation. For this purpose efficient algorithms are necessary, which have to be evaluated under constant and reproducable test conditions. This paper presents the improved version of a phantom which can generate artificial pulse waves in a synthetic tissue phantom. The tissue phantom consists of several layers that mimic the different optical properties of the fetal and maternal tissue layers. Additionally an artificial vascular system and a dome, which mimics the bending of the belly of a pregnant woman, are incorporated. To obtain data on the pulse waves, several measurement methods are included, to help understand the behavior of the signals gained from the pulse waves. Besides pressure sensors and a transmissive method we integrated a capacitive approach, that makes use of the so called “Pin Oscillator” method. Apart from the enhancements in the tissue phantom and the measurements, we also improved the used blood substitute, which reproduces the different absorption characteristics of fetal and maternal blood. The results show that the phantom can generate pulse waves similar to the natural ones. Furthermore, the phantom represents a reference that can be used to evaluate the algorithms for transabdominal, fetal pulse oximetry.

Active music therapy improves cognition and behaviour in chronic vascular encephalopathy: a case report.

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Giovagnoli, Anna Rita; Oliveri, Serena; Schifano, Letizia; Raglio, Alfredo

2014-02-01

This study describes the effects of active music therapy (AMT) on cognition and behaviour in chronic vascular encephalopathy. A single case study investigated different cognitive and psycho-behavioural changes after AMT. An adult patient with memory, attention, and verbal fluency deficits associated with Vascular Cognitive Impairment-No Dementia (VCI-ND) was treated. A four-months AMT course was based on creative and interactive music playing. Sixteen sessions were conducted simultaneously to the pharmacological therapy. Cognitive performances, mood, interpersonal interactions, and perceived abilities were assessed using standardized neuropsychological and psycho-behavioural measurements. At baseline, the patient reported a tendency to feel tense, nervous, and angry and difficulties in memory and visuospatial performances, frequently accompanied by attention drops. The social network was a habitual component of the patient's life, but not a source of sharing of personal experiences, safety or comfort. Neuropsychological tests showed deficits in object and figure naming, verbal fluency, short and long-term verbal memory, short-term spatial memory, selective attention, and visuomotor coordination. After AMT, the cognitive profile significantly improved in attention, visuomotor coordination, and verbal and spatial memory. Such positive changes were confirmed at the three-months follow-up. An increase of the interpersonal interactions and consistent reduction of anxiety were also observed. In selected patients with VCI-ND, a well-structured AMT intervention added to standard therapy may contribute in determining a stable improvement of cognitive and psycho-behavioural aspects. Controlled studies are needed to confirm these promising results. Copyright © 2013 Elsevier Ltd. All rights reserved.

Adipokine CTRP6 improves PPARγ activation to alleviate angiotensin II-induced hypertension and vascular endothelial dysfunction in spontaneously hypertensive rats

International Nuclear Information System (INIS)

Chi, Liyi; Hu, Xiaojing; Zhang, Wentao; Bai, Tiao; Zhang, Linjing; Zeng, Hua; Guo, Ruirui; Zhang, Yanhai; Tian, Hongyan

2017-01-01

Angiotensin II (AngII) is the most important component of angiotensin, which has been regarded as a major contributor to the incidence of hypertension and vascular endothelial dysfunction. The adipocytokine C1q/TNF-related protein 6 (CTRP6) was recently reported to have multiple protective effects on cardiac and cardiovascular function. However, the exact role of CTRP6 in the progression of AngII induced hypertension and vascular endothelial function remains unclear. Here, we showed that serum CTRP6 content was significantly downregulated in SHRs, accompanied by a marked increase in arterial systolic pressure and serum AngII, CRP and ET-1 content. Then, pcDNA3.1-mediated CTRP6 delivery or CTRP6 siRNA was injected into SHRs. CTRP6 overexpression caused a significant decrease in AngII expression and AngII-mediated hypertension and vascular endothelial inflammation. In contrast, CTRP6 knockdown had the opposite effect to CTRP6 overexpression. Moreover, we found that CTRP6 positively regulated the activation of the ERK1/2 signaling pathway and the expression of peroxisome proliferator-activated receptor γ (PPARγ), a recently proven negative regulator of AngII, in the brain and vascular endothelium of SHRs. Finally, CTRP6 was overexpressed in endothelial cells, and caused a significant increase in PPARγ activation and suppression in AngII-mediated vascular endothelial dysfunction and apoptosis. The effect of that could be rescued by the ERK inhibitor PD98059. In contrast, silencing CTRP6 suppressed PPARγ activation and exacerbated AngII-mediated vascular endothelial dysfunction and apoptosis. In conclusion, CTRP6 improves PPARγ activation and alleviates AngII-induced hypertension and vascular endothelial dysfunction. - Highlights: • Serum CTRP6 was significantly decreased in spontaneously hypertensive rats (SHRs). • CTRP6 positively regulated the activation of the ERK1/2 signaling pathway. • CTRP6 negatively regulates PPARγ mediated Angiotensin II (Ang

Vascular calcifications on the preoperative radiograph: harbinger of tourniquet failure in patients undergoing total knee arthroplasty?

Energy Technology Data Exchange (ETDEWEB)

Woelfle-Roos, Julia Verena; Dautel, Laura; Bieger, Ralf; Reichel, Heiko [University of Ulm, Department of Orthopaedic Surgery, Ulm (Germany); Mayer, Benjamin [University of Ulm, Institute of Epidemiology and Medical Biometrics, Ulm (Germany); Woelfle, Klaus-Dieter [Klinikum Augsburg, Vascular Surgery Division, Surgical Center, Augsburg (Germany)

2017-09-15

Vascular calcifications on the preoperative radiograph of patients scheduled for total knee arthroplasty (TKA) often give rise to concern, as their clinical relevance remains uncertain. The aim of this study was to investigate whether these vascular calcifications - especially medial artery calcifications (MACs), which increase arterial stiffness - were associated with tourniquet failure and thus with increased intraoperative blood loss. A total of 765 patients who underwent primary TKA with a tourniquet (cuff pressure 350 mmHg) between 2009 and 2011 were screened for vascular calcifications on the preoperative radiograph. Vascular calcifications were classified into intimal and medial artery calcifications. Intraoperative blood loss of patients with and without MAC was compared, and a mixed linear regression model was used to adjust for the presence of several confounding factors (e.g., obesity, operating time). None of the 50 (6.5%) patients with MAC showed signs of tourniquet failure. Intraoperative blood loss of patients with MAC was not significantly elevated compared to the overall study group (p = 0.592) even when corrected for the presence of several confounding factors. We found no evidence that vascular calcifications seen on the preoperative radiograph might be associated with tourniquet failure. However, surgeons should be aware of this possibility as tourniquet failure might become more common considering the ongoing trend toward minimizing cuff pressures. (orig.)

Rare vascular plant species at risk : recovery by seeding?

NARCIS (Netherlands)

Pegtel, Dick M.

. Rare vascular plant species are endangered worldwide. Population losses are most commonly caused by human-related factors. Conservation management seeks to halt this adverse trend and if possible, to enhance long-lasting self-sustainable populations. In general, rare species are poorly recruited

Image Quality in Vascular Radiology

International Nuclear Information System (INIS)

Vanhavere, F.; Struelens, L.

2005-01-01

In vascular radiology, the radiologists use the radiological image to diagnose or treat a specific vascular structure. From literature, we know that related doses are high and that large dose variability exists between different hospitals. The application of the optimization principle is therefore necessary and is obliged by the new legislation. So far, very little fieldwork has been performed and no practical instructions are available to do the necessary work. It's indisputable that obtaining quantitative data is of great interest for optimization purposes. In order to gain insight into these doses and the possible measures for dose reduction, we performed a comparative study in 7 hospitals. Patient doses will be measured and calculated for specific procedures in vascular radiology and evaluated against their most influencing parameters. In view of optimization purposes, a protocol for dose audit will be set-up. From the results and conclusions in this study, experimentally based guidelines will be proposed, in order to improve clinical practice in vascular radiology

Intentional Weight Loss Improved Performance in Obese Ischaemic Heart Patient

DEFF Research Database (Denmark)

Geiker, Nina; Myint, Khin Swe; Heck, Patrick

2014-01-01

Aims: The risk of heart failure (HF) increases with BMI, but paradoxically obesity has been associated with reduced mortality in patients with HF. The effect of intentional or therapeutic weight loss on HF is not well known. We examined the effect of weight loss induced by low energy diet (LED......) on physical performance and cardiovascular risk factors in obese patients with moderate-to-severe HF and/or ischaemic heart disease (IHD). Methods and Results: Results from two weight loss interventions at two centres, one in Denmark (DK - 12 week intervention in 21 subjects (14 LED, 7 controls)) and one.......1 in the intervention group versus -22.1% ± 25.6 in the control group (P=0.000). Treatment also improved triglycerides (P=0.000), very low lipoprotein (P=0.001) and C-reactive protein (P=0.010). Conclusion: Weight loss induced by LED in obese patients with moderate-to-severe HF or IHD resulted in clinically significant...

Dietary nitrate improves vascular function in patients with hypercholesterolemia: a randomized, double-blind, placebo-controlled study123

Science.gov (United States)

Velmurugan, Shanti; Gan, Jasmine Ming; Rathod, Krishnaraj S; Khambata, Rayomand S; Ghosh, Suborno M; Hartley, Amy; Van Eijl, Sven; Sagi-Kiss, Virag; Chowdhury, Tahseen A; Curtis, Mike; Kuhnle, Gunter GC; Wade, William G; Ahluwalia, Amrita

2016-01-01

Background: The beneficial cardiovascular effects of vegetables may be underpinned by their high inorganic nitrate content. Objective: We sought to examine the effects of a 6-wk once-daily intake of dietary nitrate (nitrate-rich beetroot juice) compared with placebo intake (nitrate-depleted beetroot juice) on vascular and platelet function in untreated hypercholesterolemics. Design: A total of 69 subjects were recruited in this randomized, double-blind, placebo-controlled parallel study. The primary endpoint was the change in vascular function determined with the use of ultrasound flow-mediated dilatation (FMD). Results: Baseline characteristics were similar between the groups, with primary outcome data available for 67 patients. Dietary nitrate resulted in an absolute increase in the FMD response of 1.1% (an ∼24% improvement from baseline) with a worsening of 0.3% in the placebo group (P nitrate group, showing a trend (P = 0.06) to improvement in comparison with the placebo group. Dietary nitrate also caused a small but significant reduction (7.6%) in platelet-monocyte aggregates compared with an increase of 10.1% in the placebo group (P = 0.004), with statistically significant reductions in stimulated (ex vivo) P-selectin expression compared with the placebo group (P nitrate were detected. The composition of the salivary microbiome was altered after the nitrate treatment but not after the placebo treatment (P nitrate treatment; of those taxa present, 2 taxa were responsible for >1% of this change, with the proportions of Rothia mucilaginosa trending to increase and Neisseria flavescens (P nitrate treatment relative to after placebo treatment. Conclusions: Sustained dietary nitrate ingestion improves vascular function in hypercholesterolemic patients. These changes are associated with alterations in the oral microbiome and, in particular, nitrate-reducing genera. Our findings provide additional support for the assessment of the potential of dietary nitrate as a

Endothelial Estrogen Receptor-α Does Not Protect Against Vascular Stiffness Induced by Western Diet in Female Mice.

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Manrique, Camila; Lastra, Guido; Ramirez-Perez, Francisco I; Haertling, Dominic; DeMarco, Vincent G; Aroor, Annayya R; Jia, Guanghong; Chen, Dongqing; Barron, Brady J; Garro, Mona; Padilla, Jaume; Martinez-Lemus, Luis A; Sowers, James R

2016-04-01

Consumption of a diet high in fat and refined carbohydrates (Western diet [WD]) is associated with obesity and insulin resistance, both major risk factors for cardiovascular disease (CVD). In women, obesity and insulin resistance abrogate the protection against CVD likely afforded by estrogen signaling through estrogen receptor (ER)α. Indeed, WD in females results in increased vascular stiffness, which is independently associated with CVD. We tested the hypothesis that loss of ERα signaling in the endothelium exacerbates WD-induced vascular stiffening in female mice. We used a novel model of endothelial cell (EC)-specific ERα knockout (EC-ERαKO), obtained after sequential crossing of the ERα double floxed mice and VE-Cadherin Cre-recombinase mice. Ten-week-old females, EC-ERαKO and aged-matched genopairs were fed either a regular chow diet (control diet) or WD for 8 weeks. Vascular stiffness was measured in vivo by pulse wave velocity and ex vivo in aortic explants by atomic force microscopy. In addition, vascular reactivity was assessed in isolated aortic rings. Initial characterization of the model fed a control diet did not reveal changes in whole-body insulin sensitivity, aortic vasoreactivity, or vascular stiffness in the EC-ERαKO mice. Interestingly, ablation of ERα in ECs reduced WD-induced vascular stiffness and improved endothelial-dependent dilation. In the setting of a WD, endothelial ERα signaling contributes to vascular stiffening in females. The precise mechanisms underlying the detrimental effects of endothelial ERα in the setting of a WD remain to be elucidated.

Improving hemocompatibility and accelerating endothelialization of vascular stents by a copper-titanium film

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Liu, Hengquan, E-mail: 99xyxy@163.com [College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059 (China); Pan, Changjiang [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huaiyin 223033 (China); Zhou, Shijie; Li, Junfeng [College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059 (China); Huang, Nan [Key Laboratory for Advanced Technologies of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031 (China); Dong, Lihua [Department of Research & Development, Lifetech Scientific (Shenzhen) Co., Ltd, Shenzhen 518057 (China)

2016-12-01

Bio-inorganic films and drug-eluting coatings are usually used to improve the hemocompatibility and inhibit restenosis of vascular stent; however, above bio-performances couldn't combine together with single materials. In the present study, we reported a simple approach to fabricate a metal film with the aim of imparting the stent with good blood compatibility and accelerating endothelialization. The films with various ratios of Cu and Ti were prepared through the physical vapor deposition. Phase structure and element composition were investigated by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. The releasing volume of copper ion in Cu/Ti film was determined by immersing test. The hemolysis ratio, platelet adhesion and clotting time were applied to evaluate the hemocompatibility. The proliferative behaviors of endothelial cells and smooth muscle cells under certain copper concentration were investigated in vitro and in vivo. Results indicated that copper-titanium films exhibited good hemocompatibility in vitro; however, the increase of Cu/Ti ratio could lead to increasing hemolysis ratio. Endothelial cells displayed more proliferative than smooth muscle cells when the copper concentration was < 7.5 μg/ml, however both cells tended to apoptosis to some degree when the copper concentration was increased. The complete endothelialization of the film with low copper in vivo was observed at the 2nd week, indicating that the copper-titanium film with the lower copper concentration could promote endothelialization. Therefore, the inorganic copper-titanium film could be potential biomaterials to improve blood compatibility and accelerating endothelialization of vascular stents. - Highlight: • The Cu/Ti film with regulating the various responses of ECs and SMCs has been prepared. • The hemocompatibility of Cu/Ti film is favorable and regulatable. • The volume of copper ion released from film could be designed. �

Lipid lowering and HDL raising gene transfer increase endothelial progenitor cells, enhance myocardial vascularity, and improve diastolic function.

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Stephanie C Gordts

Full Text Available BACKGROUND: Hypercholesterolemia and low high density lipoprotein (HDL cholesterol contribute to coronary heart disease but little is known about their direct effects on myocardial function. Low HDL and raised non-HDL cholesterol levels carried increased risk for heart failure development in the Framingham study, independent of any association with myocardial infarction. The objective of this study was to test the hypothesis that increased endothelial progenitor cell (EPC number and function after lipid lowering or HDL raising gene transfer in C57BL/6 low density lipoprotein receptor deficient (LDLr(-/- mice may be associated with an enhanced relative vascularity in the myocardium and an improved cardiac function. METHODOLOGY/PRINCIPAL FINDINGS: Lipid lowering and HDL raising gene transfer were performed using the E1E3E4-deleted LDLr expressing adenoviral vector AdLDLr and the human apolipoprotein A-I expressing vector AdA-I, respectively. AdLDLr transfer in C57BL/6 LDLr(-/- mice resulted in a 2.0-fold (p<0.05 increase of the circulating number of EPCs and in an improvement of EPC function as assessed by ex vivo EPC migration and EPC adhesion. Capillary density and relative vascularity in the myocardium were 28% (p<0.01 and 22% (p<0.05 higher, respectively, in AdLDLr mice compared to control mice. The peak rate of isovolumetric relaxation was increased by 12% (p<0.05 and the time constant of isovolumetric relaxation was decreased by 14% (p<0.05 after AdLDLr transfer. Similarly, HDL raising gene transfer increased EPC number and function and raised both capillary density and relative vascularity in the myocardium by 24% (p<0.05. The peak rate of isovolumetric relaxation was increased by 16% (p<0.05 in AdA-I mice compared to control mice. CONCLUSIONS/SIGNIFICANCE: Both lipid lowering and HDL raising gene transfer have beneficial effects on EPC biology, relative myocardial vascularity, and diastolic function. These findings raise concerns over the

Vascular surgery research in the Gulf Cooperation Council countries

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Ali Jawas

2014-04-01

Conclusion: The quality and quantity of vascular surgery research in the GCC countries should be improved to answer important local questions related to vascular diseases. This needs better strategic planning and more collaboration between various institutions.

Photodynamic therapy induced vascular damage: an overview of experimental PDT

International Nuclear Information System (INIS)

Wang, W; Moriyama, L T; Bagnato, V S

2013-01-01

Photodynamic therapy (PDT) has been developed as one of the most important therapeutic options in the treatment of cancer and other diseases. By resorting to the photosensitizer and light, which convert oxygen into cytotoxic reactive oxygen species (ROS), PDT will induce vascular damage and direct tumor cell killing. Another consequence of PDT is the microvascular stasis, which results in hypoxia and further produces tumor regression. To improve the treatment with PDT, three promising strategies are currently attracting much interest: (1) the combination of PDT and anti-angiogenesis agents, which more effectively prevent the proliferation of endothelial cells and the formation of new blood vessels; (2) the nanoparticle-assisted delivery of photosensitizer, which makes the photosensitizer more localized in tumor sites and thus renders minimal damage to the normal tissues; (3) the application of intravascular PDT, which can avoid the loss of energy during the transmission and expose the target area directly. Here we aim to review the important findings on vascular damage by PDT on mice. The combination of PDT with other approaches as well as its effect on cancer photomedicine are also reviewed. (review)

Oxidative and inflammatory signals in obesity-associated vascular abnormalities.

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Reho, John J; Rahmouni, Kamal

2017-07-15

Obesity is associated with increased cardiovascular morbidity and mortality in part due to vascular abnormalities such as endothelial dysfunction and arterial stiffening. The hypertension and other health complications that arise from these vascular defects increase the risk of heart diseases and stroke. Prooxidant and proinflammatory signaling pathways as well as adipocyte-derived factors have emerged as critical mediators of obesity-associated vascular abnormalities. Designing treatments aimed specifically at improving the vascular dysfunction caused by obesity may provide an effective therapeutic approach to prevent the cardiovascular sequelae associated with excessive adiposity. In this review, we discuss the recent evidence supporting the role of oxidative stress and cytokines and inflammatory signals within the vasculature as well as the impact of the surrounding perivascular adipose tissue (PVAT) on the regulation of vascular function and arterial stiffening in obesity. In particular, we focus on the highly plastic nature of the vasculature in response to altered oxidant and inflammatory signaling and highlight how weight management can be an effective therapeutic approach to reduce the oxidative stress and inflammatory signaling and improve vascular function. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Angiogenesis, Cancer, and Vascular Aging

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Junji Moriya

2017-10-01

Full Text Available Several lines of evidence have revealed that the angiogenic response to ischemic injury declines with age, which might account for the increased morbidity and mortality of cardiovascular disease (CVD among the elderly. While impairment of angiogenesis with aging leads to delayed wound healing or exacerbation of atherosclerotic ischemic diseases, it also inhibits the progression of cancer. Age-related changes of angiogenesis have been considered to at least partly result from vascular aging or endothelial cell senescence. There is considerable evidence supporting the hypothesis that vascular cell senescence contributes to the pathogenesis of age-related CVD, suggesting that vascular aging could be an important therapeutic target. Since therapeutic angiogenesis is now regarded as a promising concept for patients with ischemic CVD, it has become even more important to understand the detailed molecular mechanisms underlying impairment of angiogenesis in older patients. To improve the usefulness of therapeutic angiogenesis, approaches are needed that can compensate for impaired angiogenic capacity in the elderly while not promoting the development or progression of malignancy. In this review, we briefly outline the mechanisms of angiogenesis and vascular aging, followed by a description of how vascular aging leads to impairment of angiogenesis. We also examine potential therapeutic approaches that could enhance angiogenesis and/or vascular function in the elderly, as well as discussing the possibility of anti-senescence therapy or reversal of endothelial cell senescence.

Accelerated Vascular Aging as a Paradigm for Hypertensive Vascular Disease: Prevention and Therapy.

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Barton, Matthias; Husmann, Marc; Meyer, Matthias R

2016-05-01

Aging is considered the most important nonmodifiable risk factor for cardiovascular disease and death after age 28 years. Because of demographic changes the world population is expected to increase to 9 billion by the year 2050 and up to 12 billion by 2100, with several-fold increases among those 65 years of age and older. Healthy aging and prevention of aging-related diseases and associated health costs have become part of political agendas of governments around the world. Atherosclerotic vascular burden increases with age; accordingly, patients with progeria (premature aging) syndromes die from myocardial infarctions or stroke as teenagers or young adults. The incidence and prevalence of arterial hypertension also increases with age. Arterial hypertension-like diabetes and chronic renal failure-shares numerous pathologies and underlying mechanisms with the vascular aging process. In this article, we review how arterial hypertension resembles premature vascular aging, including the mechanisms by which arterial hypertension (as well as other risk factors such as diabetes mellitus, dyslipidemia, or chronic renal failure) accelerates the vascular aging process. We will also address the importance of cardiovascular risk factor control-including antihypertensive therapy-as a powerful intervention to interfere with premature vascular aging to reduce the age-associated prevalence of diseases such as myocardial infarction, heart failure, hypertensive nephropathy, and vascular dementia due to cerebrovascular disease. Finally, we will discuss the implementation of endothelial therapy, which aims at active patient participation to improve primary and secondary prevention of cardiovascular disease. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Improved ice loss estimate of the northwestern Greenland ice sheet

DEFF Research Database (Denmark)

Kjeldsen, Kristian Kjellerup; Khan, Shfaqat Abbas; Wahr, J.

2013-01-01

We estimate ice volume change rates in the northwest Greenland drainage basin during 2003–2009 using Ice, Cloud and land Elevation Satellite (ICESat) laser altimeter data. Elevation changes are often reported to be largest near the frontal portion of outlet glaciers. To improve the volume change...... estimate, we supplement the ICESat data with altimeter surveys from NASA's Airborne Topographic Mapper from 2002 to 2010 and NASA's Land, Vegetation and Ice Sensor from 2010. The Airborne data are mainly concentrated along the ice margin and thus have a significant impact on the estimate of the volume...... change. Our results show that adding Airborne Topographic Mapper and Land, Vegetation and Ice Sensor data to the ICESat data increases the catchment-wide estimate of ice volume loss by 11%, mainly due to an improved volume loss estimate along the ice sheet margin. Furthermore, our results show...

Smoking Cessation Counseling Improves Quality of Care and Surgical Outcomes with Financial Gain for a Vascular Practice.

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Moses, D A; Mehaffey, J H; Strider, D V; Tracci, M C; Kern, J A; Upchurch, G R

2017-07-01

Cigarette smoking is strongly associated with atherosclerotic disease. It is incumbent on vascular surgeons to provide smoking cessation counseling (SCC) to their patients. The objective of this study was to determine the association of SCC and improvement in quality of care. As a quality project using retrospective data, the study received institutional review board exemption status. A retrospective review of prospectively maintained database from April 2014 through March 2015 of outpatient encounters in a vascular surgery clinic was performed of current smokers. Through the quality support team, providers were encouraged to counsel smokers to quit, document the discussion, and bill specific Evaluate and Management codes (99406 and 99407). The number of outpatients by smoking status, documentation and billing of SCC, demographics of current smokers, and monetary collections were collected. Data were compared using a correlation coefficient calculated and tested for statistical significant using two-tailed t-test. A sample of 1,077 visits by 612 currently smoking patients accounted for 24% of all outpatient vascular surgery visits. The average age was 61 years, and 64% were male. Comorbidities included 77% with hypertension, 32% with diabetes mellitus, and 14% with chronic kidney disease. Medically, 72% were on aspirin, 71% on statin, and 48% on beta blocker. A total of 208 (34%) never underwent a vascular intervention, and 183 (30%) had an intervention during the study period (44% for peripheral artery disease, 10% for carotid stenosis, 14% amputations, and 10% abdominal aortic aneurysm). Documentation improved from 65% of encounters during the first month to 89% in the peak month and 79% of total encounters. All-cause mortality rate was 2%, and this cohort demonstrated 75% SCC for 28 encounters. Fifty-five patients (9%) quit smoking for more than 30 days at the end of the study period, and this cohort had 69% of their 97 encounters with documented SCC

Juvenile nasopharyngeal angiofibroma: vascular determinates for operative complications and tumor recurrence.

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Chan, Kenny H; Gao, Dexiang; Fernandez, Patrick G; Kingdom, Todd T; Kumpe, David A

2014-03-01

Operative complications and tumor recurrence in juvenile nasopharyngeal angiofibroma (JNA) are measurable and meaningful outcomes. This study aimed to assess the association of these two outcomes to various clinical indices and in particular, vascular determinates. Retrospective cohort study. An 18-year retrospective chart review of an academic tertiary center was undertaken. Data from clinical notes, imaging studies, and arteriograms were analyzed. Thirty-seven male (mean age, 14.4 years) patients were included in the study. Tumor stages included: IA (three), IB (three), IIA (14), IIB (three), IIC (five), IIIA (five), and IIIB (four). Four complications (cerebrospinal fluid leak, cerebral vascular accident, and two transient ocular defects) occurred. Eight recurrences occurred within 24 months following surgery. Complications were associated with estimated intraoperative blood loss (EBL) (P = .045). Tumor recurrence was associated with feeding vessels from the contralateral internal carotid artery (ICA) (P = .017). EBL was significantly associated with surgical technique used. EBL, tumor stage, and tumor vascular supply were significantly associated with each other. Vascular factors were associated with JNA complication and tumor recurrence. EBL might affect complications, and contralateral ICA as a feeding vessel might affect recurrence. EBL was influenced by procedure choice and was interrelated to size and vascular supply of the tumor. This study bolsters the need to decrease intraoperative blood loss by preoperative embolization and use of endoscopic removal techniques. Furthermore, when branches of the ICA are found to be feeding vessels, greater surgical attention for a dry surgical field is encouraged. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Endothelium derived nitric oxide synthase negatively regulates the PDGF-survivin pathway during flow-dependent vascular remodeling.

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Jun Yu

Full Text Available Chronic alterations in blood flow initiate structural changes in vessel lumen caliber to normalize shear stress. The loss of endothelial derived nitric oxide synthase (eNOS in mice promotes abnormal flow dependent vascular remodeling, thus uncoupling mechanotransduction from adaptive vascular remodeling. However, the mechanisms of how the loss of eNOS promotes abnormal remodeling are not known. Here we show that abnormal flow-dependent remodeling in eNOS knockout mice (eNOS (-/- is associated with activation of the platelet derived growth factor (PDGF signaling pathway leading to the induction of the inhibitor of apoptosis, survivin. Interfering with PDGF signaling or survivin function corrects the abnormal remodeling seen in eNOS (-/- mice. Moreover, nitric oxide (NO negatively regulates PDGF driven survivin expression and cellular proliferation in cultured vascular smooth muscle cells. Collectively, our data suggests that eNOS negatively regulates the PDGF-survivin axis to maintain proportional flow-dependent luminal remodeling and vascular quiescence.

Formal Nutritional Education Improves Weight Loss in Bariatric Patients Following Laparoscopic Sleeve Gastrectomy.

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Mangieri, Christopher Wesley; Strode, Matthew A

2016-12-01

Laparoscopic sleeve gastrectomy (LSG) is an increasingly performed procedure in the bariatric surgery armamentarium. This study evaluates our experience with LSG at Dwight D. Eisenhower Army Medical Center (DDEAMC) during the time period of 2008-2010. We found that the inclusion of formal nutritional education significantly increased our weight loss results following LSG. This is a retrospective review from our LSG caseload from 2008 to 2010. During that time, we performed 159 LSG. In our review, we performed comparative data of all operative years during 2008-2010 for up to 3 years postoperatively. Our main focus was in regard to weight loss as measured by percentage of excess body weight loss (%EWL), percentage of total weight loss (%TWL), and percentage of excess BMI loss (%EBL). We also evaluated the effect of LSG on diabetes mellitus (DM) and hypertension (HTN) postoperatively. We found an improvement in our %EWL, %TWL, and %EBL rates in our LSG cases following the inclusion of formal nutritional education. There was a mean increase in %EWL of 15 %, %TWL of 7 %, and %EBL of 21 %, which were statistically significant, that was present at all postoperative years of follow-up. We determined the only variable that changed in our bariatric program starting in 2010 was the inclusion of formal nutritional education. We also found a statistically significant improvement in resolution of HTN with the inclusion of formal nutritional education. The addition of formal nutritional education can enhance weight loss following bariatric surgery. We have shown a significant improvement in weight loss results following LSG with the implementation of formal nutritional education; this is the only study to our knowledge evaluating formal nutritional education and LSG.

Audit of the Danish national vascular database

DEFF Research Database (Denmark)

Levi-Mazloum, Niels Donald; Jensen, L P; Schroeder, T V

1996-01-01

The accuracy of data contained in the Danish vascular database was compared with the case notes. A total of 100 case notes were reviewed for 11 pertinent variables in the database. A high error rate ranging from 2 to 34% was found. Also, approximately 10% of patients had never been entered into t...... into the vascular database. Further improvement of the Danish vascular database is necessary for its use as basis for reporting results.......The accuracy of data contained in the Danish vascular database was compared with the case notes. A total of 100 case notes were reviewed for 11 pertinent variables in the database. A high error rate ranging from 2 to 34% was found. Also, approximately 10% of patients had never been entered...

Taurine Supplementation Lowers Blood Pressure and Improves Vascular Function in Prehypertension: Randomized, Double-Blind, Placebo-Controlled Study.

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Sun, Qianqian; Wang, Bin; Li, Yingsha; Sun, Fang; Li, Peng; Xia, Weijie; Zhou, Xunmei; Li, Qiang; Wang, Xiaojing; Chen, Jing; Zeng, Xiangru; Zhao, Zhigang; He, Hongbo; Liu, Daoyan; Zhu, Zhiming

2016-03-01

Taurine, the most abundant, semiessential, sulfur-containing amino acid, is well known to lower blood pressure (BP) in hypertensive animal models. However, no rigorous clinical trial has validated whether this beneficial effect of taurine occurs in human hypertension or prehypertension, a key stage in the development of hypertension. In this randomized, double-blind, placebo-controlled study, we assessed the effects of taurine intervention on BP and vascular function in prehypertension. We randomly assigned 120 eligible prehypertensive individuals to receive either taurine supplementation (1.6 g per day) or a placebo for 12 weeks. Taurine supplementation significantly decreased the clinic and 24-hour ambulatory BPs, especially in those with high-normal BP. Mean clinic systolic BP reduction for taurine/placebo was 7.2/2.6 mm Hg, and diastolic BP was 4.7/1.3 mm Hg. Mean ambulatory systolic BP reduction for taurine/placebo was 3.8/0.3 mm Hg, and diastolic BP was 3.5/0.6 mm Hg. In addition, taurine supplementation significantly improved endothelium-dependent and endothelium-independent vasodilation and increased plasma H2S and taurine concentrations. Furthermore, changes in BP were negatively correlated with both the plasma H2S and taurine levels in taurine-treated prehypertensive individuals. To further elucidate the hypotensive mechanism, experimental studies were performed both in vivo and in vitro. The results showed that taurine treatment upregulated the expression of hydrogen sulfide-synthesizing enzymes and reduced agonist-induced vascular reactivity through the inhibition of transient receptor potential channel subtype 3-mediated calcium influx in human and mouse mesenteric arteries. In conclusion, the antihypertensive effect of chronic taurine supplementation shows promise in the treatment of prehypertension through improvement of vascular function. © 2016 American Heart Association, Inc.

Insulin resistance: vascular function and exercise

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Moon-Hyon Hwang

2016-09-01

Full Text Available Insulin resistance associated with metabolic syndrome and Type 2 diabetes mellitus is an epidemic metabolic disorder, which increases the risk of cardiovascular complications. Impaired vascular endothelial function is an early marker for atherosclerosis, which causes cardiovascular complications. Both experimental and clinical studies indicate that endothelial dysfunction in vasculatures occurs with insulin resistance. The associated physiological mechanisms are not fully appreciated yet, however, it seems that augmented oxidative stress, a physiological imbalance between oxidants and antioxidants, in vascular cells is a possible mechanism involved in various vascular beds with insulin resistance and hyperglycemia. Regardless of the inclusion of resistance exercise, aerobic exercise seems to be beneficial for vascular endothelial function in both large conduit and small resistance vessels in both clinical and experimental studies with insulin resistance. In clinical cases, aerobic exercise over 8 weeks with higher intensity seems more beneficial than the cases with shorter duration and lower intensity. However, more studies are needed in the future to elucidate the physiological mechanisms by which vascular endothelial function is impaired in insulin resistance and improved with aerobic exercise.

Validation of the Society for Vascular Surgery's objective performance goals for critical limb ischemia in everyday vascular surgery practice.

Science.gov (United States)

Goodney, Philip P; Schanzer, Andres; Demartino, Randall R; Nolan, Brian W; Hevelone, Nathanael D; Conte, Michael S; Powell, Richard J; Cronenwett, Jack L

2011-07-01

To develop standardized metrics for expected outcomes in lower extremity revascularization for critical limb ischemia (CLI), the Society for Vascular Surgery (SVS) has developed objective performance goals (OPGs) based on aggregate data from randomized trials of lower extremity bypass (LEB). It remains unknown, however, if these targets can be achieved in everyday vascular surgery practice. We applied SVS OPG criteria to 1039 patients undergoing 1039 LEB operations for CLI with autogenous vein (excluding patients on dialysis) within the Vascular Study Group of New England (VSGNE). Each of the individual OPGs was calculated within the VSGNE dataset, along with its surrounding 95% confidence intervals (CIs) and compared to published SVS OPGs using χ(2) comparisons and survival analysis. Across most risk strata, patients in the VSGNE and SVS OPG cohorts were similar (clinical high-risk [age >80 years and tissue loss]: 15.3% VSGNE; 16.2% SVS OPG; P = .58; anatomic high risk [infrapopliteal target artery]: 57.8% VSGNE; 60.2% SVS OPG; P = .32). However, the proportion of VSGNE patients designated as conduit high-risk (lack of single-segment great saphenous vein) was lower (10.2% VSGNE; 26.9% SVS OPG;P Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Non-invasive stem cell therapy in a rat model for retinal degeneration and vascular pathology.

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Shaomei Wang

Full Text Available BACKGROUND: Retinitis pigmentosa (RP is characterized by progressive night blindness, visual field loss, altered vascular permeability and loss of central vision. Currently there is no effective treatment available except gene replacement therapy has shown promise in a few patients with specific gene defects. There is an urgent need to develop therapies that offer generic neuro-and vascular-protective effects with non-invasive intervention. Here we explored the potential of systemic administration of pluripotent bone marrow-derived mesenchymal stem cells (MSCs to rescue vision and associated vascular pathology in the Royal College Surgeons (RCS rat, a well-established animal model for RP. METHODOLOGY/PRINCIPAL FINDINGS: Animals received syngeneic MSCs (1x10(6 cells by tail vein at an age before major photoreceptor loss. PRINCIPAL RESULTS: both rod and cone photoreceptors were preserved (5-6 cells thick at the time when control animal has a single layer of photoreceptors remained; Visual function was significantly preserved compared with controls as determined by visual acuity and luminance threshold recording from the superior colliculus; The number of pathological vascular complexes (abnormal vessels associated with migrating pigment epithelium cells and area of vascular leakage that would ordinarily develop were dramatically reduced; Semi-quantitative RT-PCR analysis indicated there was upregulation of growth factors and immunohistochemistry revealed that there was an increase in neurotrophic factors within eyes of animals that received MSCs. CONCLUSIONS/SIGNIFICANCE: These results underscore the potential application of MSCs in treating retinal degeneration. The advantages of this non-invasive cell-based therapy are: cells are easily isolated and can be expanded in large quantity for autologous graft; hypoimmunogenic nature as allogeneic donors; less controversial in nature than other stem cells; can be readministered with minor discomfort

Acute ingestion of a novel whey-derived peptide improves vascular endothelial responses in healthy individuals: a randomized, placebo controlled trial

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Kupchak Brian R

2009-07-01

Full Text Available Abstract Background Whey protein is a potential source of bioactive peptides. Based on findings from in vitro experiments indicating a novel whey derived peptide (NOP-47 increased endothelial nitric oxide synthesis, we tested its effects on vascular function in humans. Methods A randomized, placebo-controlled, crossover study design was used. Healthy men (n = 10 and women (n = 10 (25 ± 5 y, BMI = 24.3 ± 2.3 kg/m2 participated in two vascular testing days each preceded by 2 wk of supplementation with a single dose of 5 g/day of a novel whey-derived peptide (NOP-47 or placebo. There was a 2 wk washout period between trials. After 2 wk of supplementation, vascular function in the forearm and circulating oxidative stress and inflammatory related biomarkers were measured serially for 2 h after ingestion of 5 g of NOP-47 or placebo. Macrovascular and microvascular function were assessed using brachial artery flow mediated dilation (FMD and venous occlusion strain gauge plethysmography. Results Baseline peak FMD was not different for Placebo (7.7% and NOP-47 (7.8%. Placebo had no effect on FMD at 30, 60, and 90 min post-ingestion (7.5%, 7.2%, and 7.6%, respectively whereas NOP-47 significantly improved FMD responses at these respective postprandial time points compared to baseline (8.9%, 9.9%, and 9.0%; P P = 0.008 for time × trial interaction. Plasma myeloperoxidase was increased transiently by both NOP-47 and placebo, but there were no changes in markers inflammation. Plasma total nitrites/nitrates significantly decreased over the 2 hr post-ingestion period and were lower at 120 min after placebo (-25% compared to NOP-47 (-18%. Conclusion These findings indicate that supplementation with a novel whey-derived peptide in healthy individuals improves vascular function.

Effect of agmatine on experimental vascular endothelial dysfunction.

Science.gov (United States)

Nader, M A; Gamiel, N M; El-Kashef, H; Zaghloul, M S

2016-05-01

This study was designed to investigate the effect of agmatine sulfate (AG, CAS2482-00-0) in nicotine (NIC)-induced vascular endothelial dysfunction (VED) in rabbits. NIC was administered to produce VED in rabbits with or without AG for 6 weeks. Serum lipid profile, serum thiobarbituric acid reactive substances, reduced glutathione, superoxide dismutase generation, serum nitrite/nitrate, serum vascular cellular adhesion molecule-1 (VCAM-1), and aortic nuclear factor κB (NF-κB) levels were analyzed.Treatment with AG markedly improves lipid profile and prevented NIC-induced VED and oxidative stress. The mechanism of AG in improving NIC-induced VED may be due to the significant reduction in serum VCAM-1 levels and aortic NF-κB. Thus, it may be concluded that AG reduces the oxidative stress, nitric oxide production, VCAM-1 levels, and aortic NF-κB expression, thereby consequently improving the integrity of vascular endothelium. © The Author(s) 2015.

The skeletal vascular system - Breathing life into bone tissue.

Science.gov (United States)

Stegen, Steve; Carmeliet, Geert

2017-08-26

During bone development, homeostasis and repair, a dense vascular system provides oxygen and nutrients to highly anabolic skeletal cells. Characteristic for the vascular system in bone is the serial organization of two capillary systems, each typified by specific morphological and physiological features. Especially the arterial capillaries mediate the growth of the bone vascular system, serve as a niche for skeletal and hematopoietic progenitors and couple angiogenesis to osteogenesis. Endothelial cells and osteoprogenitor cells interact not only physically, but also communicate to each other by secretion of growth factors. A vital angiogenic growth factor is vascular endothelial growth factor and its expression in skeletal cells is controlled by osteogenic transcription factors and hypoxia signaling, whereas the secretion of angiocrine factors by endothelial cells is regulated by Notch signaling, blood flow and possibly hypoxia. Bone loss and impaired fracture repair are often associated with reduced and disorganized blood vessel network and therapeutic targeting of the angiogenic response may contribute to enhanced bone regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

Chronic mild hypoxia promotes profound vascular remodeling in spinal cord blood vessels, preferentially in white matter, via an α5β1 integrin-mediated mechanism.

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Halder, Sebok K; Kant, Ravi; Milner, Richard

2018-05-01

Spinal cord injury (SCI) leads to rapid destruction of neuronal tissue, resulting in devastating motor and sensory deficits. This is exacerbated by damage to spinal cord blood vessels and loss of vascular integrity. Thus, approaches that protect existing blood vessels or stimulate the growth of new blood vessels might present a novel approach to minimize loss or promote regeneration of spinal cord tissue following SCI. In light of the remarkable power of chronic mild hypoxia (CMH) to stimulate vascular remodeling in the brain, the goal of this study was to examine how CMH (8% O 2 for up to 7 days) affects blood vessel remodeling in the spinal cord. We found that CMH promoted the following: (1) endothelial proliferation and increased vascularity as a result of angiogenesis and arteriogenesis, (2) increased vascular expression of the angiogenic extracellular matrix protein fibronectin as well as concomitant increases in endothelial expression of the fibronectin receptor α5β1 integrin, (3) strongly upregulated endothelial expression of the tight junction proteins claudin-5, ZO-1 and occludin and (4) astrocyte activation. Of note, the vascular remodeling changes induced by CMH were more extensive in white matter. Interestingly, hypoxic-induced vascular remodeling in spinal cord blood vessels was markedly attenuated in mice lacking endothelial α5 integrin expression (α5-EC-KO mice). Taken together, these studies demonstrate the considerable remodeling potential of spinal cord blood vessels and highlight an important angiogenic role for the α5β1 integrin in promoting endothelial proliferation. They also imply that stimulation of the α5β1 integrin or controlled use of mild hypoxia might provide new approaches for promoting angiogenesis and improving vascular integrity in spinal cord blood vessels.

A study on improvement of analytical prediction model for spacer grid pressure loss coefficients

International Nuclear Information System (INIS)

Lim, Jonh Seon

2002-02-01

Nuclear fuel assemblies used in the nuclear power plants consist of the nuclear fuel rods, the control rod guide tubes, an instrument guide tube, spacer grids,a bottom nozzle, a top nozzle. The spacer grid is the most important component of the fuel assembly components for thermal hydraulic and mechanical design and analyses. The spacer grids fixed with the guide tubes support the fuel rods and have the very important role to activate thermal energy transfer by the coolant mixing caused to the turbulent flow and crossflow in the subchannels. In this paper, the analytical spacer grid pressure loss prediction model has been studied and improved by considering the test section wall to spacer grid gap pressure loss independently and applying the appropriate friction drag coefficient to predict pressure loss more accurately at the low Reynolds number region. The improved analytical model has been verified based on the hydraulic pressure drop test results for the spacer grids of three types with 5x5, 16x16, 17x17 arrays, respectively. The pressure loss coefficients predicted by the improved analytical model are coincident with those test results within ±12%. This result shows that the improved analytical model can be used for research and design change of the nuclear fuel assembly

Chronic Stress Improves NO- and Ca2+ Flux-Dependent Vascular Function: A Pharmacological Study

Energy Technology Data Exchange (ETDEWEB)

Bruder-Nascimento, Thiago, E-mail: bruderthiago@usp.br [Departamento de Farmacologia - Instituto de Biociências de Botucatu - Universidade do Estado de São Paulo (UNESP), Botucatu, São Paulo (Brazil); Departamento de Clínica Médica - Faculdade de Medicina de Botucatu - Universidade do Estado de São Paulo (UNESP), Botucatu, São Paulo (Brazil); Campos, Dijon Henrique Salome [Departamento de Clínica Médica - Faculdade de Medicina de Botucatu - Universidade do Estado de São Paulo (UNESP), Botucatu, São Paulo (Brazil)

2015-03-15

Stress is associated with cardiovascular diseases. This study aimed at assessing whether chronic stress induces vascular alterations, and whether these modulations are nitric oxide (NO) and Ca2+ dependent. Wistar rats, 30 days of age, were separated into 2 groups: control (C) and Stress (St). Chronic stress consisted of immobilization for 1 hour/day, 5 days/week, 15 weeks. Systolic blood pressure was assessed. Vascular studies on aortic rings were performed. Concentration-effect curves were built for noradrenaline, in the presence of L-NAME or prazosin, acetylcholine, sodium nitroprusside and KCl. In addition, Ca{sup 2+} flux was also evaluated. Chronic stress induced hypertension, decreased the vascular response to KCl and to noradrenaline, and increased the vascular response to acetylcholine. L-NAME blunted the difference observed in noradrenaline curves. Furthermore, contractile response to Ca{sup 2+} was decreased in the aorta of stressed rats. Our data suggest that the vascular response to chronic stress is an adaptation to its deleterious effects, such as hypertension. In addition, this adaptation is NO- and Ca{sup 2+}-dependent. These data help to clarify the contribution of stress to cardiovascular abnormalities. However, further studies are necessary to better elucidate the mechanisms involved in the cardiovascular dysfunction associated with stressors. (Arq Bras Cardiol. 2014; [online].ahead print, PP.0-0)

Vascular function in health, hypertension, and diabetes

DEFF Research Database (Denmark)

Nyberg, Michael Permin; Gliemann, Lasse; Hellsten, Ylva

2015-01-01

muscle, which can affect muscle function. Central aspects in the vascular impairments are alterations in the formation of prostacyclin, the bioavailability of NO and an increased formation of vasoconstrictors and reactive oxygen species (ROS). Regular physical activity effectively improves vascular......, the increase in muscle blood flow required for oxygen supply during exercise is achieved through a substantial increase in vasodilators locally formed in the active muscle tissue that overcome the vasoconstrictor signals. Most of the vasodilator signals are mediated via endothelial cells, which lead...... to the formation of vasodilators such as nitric oxide (NO) and prostacyclin. In essential hypertension and type II diabetes, the endothelial function and regulation of vascular tone is impaired with consequent increases in peripheral vascular resistance and inadequate regulation of oxygen supply to the skeletal...

Pulmonary vascular imaging

International Nuclear Information System (INIS)

Fedullo, P.F.; Shure, D.

1987-01-01

A wide range of pulmonary vascular imaging techniques are available for the diagnostic evaluation of patients with suspected pulmonary vascular disease. The characteristics of any ideal technique would include high sensitivity and specificity, safety, simplicity, and sequential applicability. To date, no single technique meets these ideal characteristics. Conventional pulmonary angiography remains the gold standard for the diagnosis of acute thromboembolic disease despite the introduction of newer techniques such as digital subtraction angiography and magnetic resonance imaging. Improved noninvasive lower extremity venous testing methods, particularly impedance plethysmography, and ventilation-perfusion scanning can play significant roles in the noninvasive diagnosis of acute pulmonary emboli when properly applied. Ventilation-perfusion scanning may also be useful as a screening test to differentiate possible primary pulmonary hypertension from chronic thromboembolic pulmonary hypertension. And, finally, angioscopy may be a useful adjunctive technique to detect chronic thromboembolic disease and determine operability. Optimal clinical decision-making, however, will continue to require the proper interpretation of adjunctive information obtained from the less-invasive techniques, applied with an understanding of the natural history of the various forms of pulmonary vascular disease and with a knowledge of the capabilities and shortcomings of the individual techniques

Major Vascular Neurocognitive Disorder: A Reappraisal to Vascular Dementia

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Emre Kumral

2017-03-01

Full Text Available Major vascular neurocognitive disorder (NCD is the second leading form of dementia after Alzheimer’s disease, accounting for 17-20% of all dementias. Vascular NCD is a progressive disease caused by reduced cerebral blood flow related to multiple large volume or lacunar infarcts that induce a sudden onset and stepwise decline in cognitive abilities. Despite its prevalence and clinical importance, there is still controversy in the terminology of vascular NCD. Only after the release of Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5 (2013 did the American Psychiatric Association define vascular dementia as “major vascular NCD”. This review includes an overview of risk factors, pathophysiology, types, diagnostic and clinical features of major vascular NCD, and current treatment options of vascular NCD regarding to DSM-5 criteria

PLVAP in diabetic retinopathy: A gatekeeper of angiogenesis and vascular permeability

NARCIS (Netherlands)

Wiśniewska-Kruk, J.

2014-01-01

Nowadays, approximately 4 million people worldwide experience blindness or severe vision loss caused by diabetic retinopathy. Diabetic retinopathy is a multifactorial disease that can progress from minor changes in vascular permeability, into a proliferative retinal disorder. The increasing

Improved reading performance using individualized compensation filters for observers with losses in central vision

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Lawton, Teri B.

1989-01-01

A method to improve the reading performance of subjects with losses in central vision is proposed in which the amplitudes of the intermediate spatial frequencies are boosted relative to the lower spatial frequencies. In the method, words are filtered using an image enhancement function which is based on a subject's losses in visual function relative to a normal subject. It was found that 30-70 percent less magnification was necessary, and that reading rates were improved 2-3 times, using the method. The individualized compensation filters improved the clarity and visibility of words. The shape of the enhancement function was shown to be important in determining the optimum compensation filter for improving reading performance.

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

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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.

The use of bovine pericardial patch for vascular reconstruction in infected fields for transplant recipients

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Sandra Garcia Aroz, MD

2017-03-01

Full Text Available Infectious vascular complications affecting transplant recipients may lead to severe morbidity and graft loss. This is a retrospective review of vascular repair with bovine pericardial patch (BPP in infected fields for immunosuppressed patients. BPP was used as either a patch or an interposition graft. Five cases of arterial reconstruction in infected fields using BPP were performed. There were no complications related to bleeding, thrombosis, or recurrent infection. In our limited experience, the use of BPP as a vascular patch is successful, and it represents an alternative when vascular reconstruction is needed in the context of infected fields.

Short-term weight loss attenuates local tissue inflammation and improves insulin sensitivity without affecting adipose inflammation in obese mice.

Science.gov (United States)

Jung, Dae Young; Ko, Hwi Jin; Lichtman, Eben I; Lee, Eunjung; Lawton, Elizabeth; Ong, Helena; Yu, Kristine; Azuma, Yoshihiro; Friedline, Randall H; Lee, Ki Won; Kim, Jason K

2013-05-01

Obesity is a major cause of insulin resistance, and weight loss is shown to improve glucose homeostasis. But the underlying mechanism and the role of inflammation remain unclear. Male C57BL/6 mice were fed a high-fat diet (HFD) for 12 wk. After HFD, weight loss was induced by changing to a low-fat diet (LFD) or exercise with continuous HFD. The weight loss effects on energy balance and insulin sensitivity were determined using metabolic cages and hyperinsulinemic euglycemic clamps in awake mice. Diet and exercise intervention for 3 wk caused a modest weight loss and improved glucose homeostasis. Weight loss dramatically reduced local inflammation in skeletal muscle, liver, and heart but not in adipose tissue. Exercise-mediated weight loss increased muscle glucose metabolism without affecting Akt phosphorylation or lipid levels. LFD-mediated weight loss reduced lipid levels and improved insulin sensitivity selectively in liver. Both weight loss interventions improved cardiac glucose metabolism. These results demonstrate that a short-term weight loss with exercise or diet intervention attenuates obesity-induced local inflammation and selectively improves insulin sensitivity in skeletal muscle and liver. Our findings suggest that local factors, not adipose tissue inflammation, are involved in the beneficial effects of weight loss on glucose homeostasis.

Cell Therapy Applications for Retinal Vascular Diseases: Diabetic Retinopathy and Retinal Vein Occlusion.

Science.gov (United States)

Park, Susanna S

2016-04-01

Retinal vascular conditions, such as diabetic retinopathy and retinal vein occlusion, remain leading causes of vision loss. No therapy exists to restore vision loss resulting from retinal ischemia and associated retinal degeneration. Tissue regeneration is possible with cell therapy. The goal would be to restore or replace the damaged retinal vasculature and the retinal neurons that are damaged and/or degenerating from the hypoxic insult. Currently, various adult cell therapies have been explored as potential treatment. They include mesenchymal stem cells, vascular precursor cells (i.e., CD34+ cells, hematopoietic cells or endothelial progenitor cells), and adipose stromal cells. Preclinical studies show that all these cells have a paracrine trophic effect on damaged ischemic tissue, leading to tissue preservation. Endothelial progenitor cells and adipose stromal cells integrate into the damaged retinal vascular wall in preclinical models of diabetic retinopathy and ischemia-reperfusion injury. Mesenchymal stem cells do not integrate as readily but appear to have a primary paracrine trophic effect. Early phase clinical trials have been initiated and ongoing using mesenchymal stem cells or autologous bone marrow CD34+ cells injected intravitreally as potential therapy for diabetic retinopathy or retinal vein occlusion. Adipose stromal cells or pluripotent stem cells differentiated into endothelial colony-forming cells have been explored in preclinical studies and show promise as possible therapies for retinal vascular disorders. The relative safety or efficacy of these various cell therapies for treating retinal vascular disorders have yet to be determined.

Additive Manufacturing of Vascular Grafts and Vascularized Tissue Constructs.

Science.gov (United States)

Elomaa, Laura; Yang, Yunzhi Peter

2017-10-01

There is a great need for engineered vascular grafts among patients with cardiovascular diseases who are in need of bypass therapy and lack autologous healthy blood vessels. In addition, because of the severe worldwide shortage of organ donors, there is an increasing need for engineered vascularized tissue constructs as an alternative to organ transplants. Additive manufacturing (AM) offers great advantages and flexibility of fabrication of cell-laden, multimaterial, and anatomically shaped vascular grafts and vascularized tissue constructs. Various inkjet-, extrusion-, and photocrosslinking-based AM techniques have been applied to the fabrication of both self-standing vascular grafts and porous, vascularized tissue constructs. This review discusses the state-of-the-art research on the use of AM for vascular applications and the key criteria for biomaterials in the AM of both acellular and cellular constructs. We envision that new smart printing materials that can adapt to their environment and encourage rapid endothelialization and remodeling will be the key factor in the future for the successful AM of personalized and dynamic vascular tissue applications.

Revascularization of diaphyseal bone segments by vascular bundle implantation.

Science.gov (United States)

Nagi, O N

2005-11-01

Vascularized bone transfer is an effective, established treatment for avascular necrosis and atrophic or infected nonunions. However, limited donor sites and technical difficulty limit its application. Vascular bundle transplantation may provide an alternative. However, even if vascular ingrowth is presumed to occur in such situations, its extent in aiding revascularization for ultimate graft incorporation is not well understood. A rabbit tibia model was used to study and compare vascularized, segmental, diaphyseal, nonvascularized conventional, and vascular bundle-implanted grafts with a combination of angiographic, radiographic, histopathologic, and bone scanning techniques. Complete graft incorporation in conventional grafts was observed at 6 months, whereas it was 8 to 12 weeks with either of the vascularized grafts. The pattern of radionuclide uptake and the duration of graft incorporation between vascular segmental bone grafts (with intact endosteal blood supply) and vascular bundle-implanted segmental grafts were similar. A vascular bundle implanted in the recipient bone was found to anastomose extensively with the intraosseous circulation at 6 weeks. Effective revascularization of bone could be seen when a simple vascular bundle was introduced into a segment of bone deprived of its normal blood supply. This simple technique offers promise for improvement of bone graft survival in clinical circumstances.

Theobromine consumption does not improve fasting and postprandial vascular function in overweight and obese subjects.

Science.gov (United States)

Smolders, Lotte; Mensink, Ronald P; van den Driessche, Jose J; Joris, Peter J; Plat, Jogchum

2018-01-12

Theobromine, a component of cocoa, may favorably affect conventional lipid-related cardiovascular risk markers, but effects on flow-mediated dilation (FMD) and other vascular function markers are not known. To evaluate the effects of 4-week theobromine consumption (500 mg/day) on fasting and postprandial vascular function markers. In a randomized, double-blind crossover study, 44 apparently healthy overweight (N = 30) and obese (N = 14) men and women with low HDL-C concentrations, consumed daily 500 mg theobromine or placebo for 4 weeks. After 4 weeks, FMD, peripheral arterial tonometry (PAT), augmentation index (AIx), pulse wave velocity (PWV), blood pressure (BP) and retinal microvasculature measurements were performed. These measurements were carried out under fasting conditions and 2.5 h after a high-fat mixed meal challenge. 4-week theobromine consumption did not change fasting vascular function markers, except for a decrease in central AIx (cAIx, - 1.7 pp, P = 0.037) and a trend towards smaller venular calibers (- 2 µm, P = 0.074). Consuming a high-fat mixed meal decreased FMD (0.89 pp, P = 0.002), reactive hyperemia index (RHI, - 0.30, P Theobromine did not modify these postprandial effects, but increased postprandially the brachial artery diameter (0.03 cm, P = 0.015), and decreased the cAIx corrected for a HR of 75 (cAIx75, - 5.0 pp, P = 0.004) and peripheral AIx (pAIx, - 6.3 pp, P = 0.017). Theobromine consumption did not improve fasting and postprandial endothelial function, but increased postprandial peripheral arterial diameters and decreased the AIx. These findings do not suggest that theobromine alone contributes to the proposed cardioprotective effects of cocoa. This trial was registered on clinicaltrials.gov under study number NCT02209025.

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

Science.gov (United States)

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.

Vascularized nerve grafts: an experimental study.

Science.gov (United States)

Donzelli, Renato; Capone, Crescenzo; Sgulò, Francesco Giovanni; Mariniello, Giuseppe; Maiuri, Francesco

2016-08-01

The aim of this study is to define an experimental model in order to promote the functional recovery of the nerves using grafts with vascular support (Vascular Nerve Grafts - VNG). The aim of this study is to define, on an experimental model in normal recipient bed, whether the functional recovery with VNG is superior to that obtained non-vascularized graft (NNG). Twenty male rabbits, which underwent dissection of sciatic nerve, were later treated by reinnervation through an autograft. In 10 animals the reconstruction of sciatic nerve was realized with VNG; in 10 control animals the reconstruction of sciatic nerve was realized with NNG. The VNG group showed a better axonal organization and a significantly higher number of regenerated axons in the early phases (after 30 days) than the NNG group, whereas the difference in the axonal number at day 90 was less significant; besides, the axon diameter and the myelin thickness were not significantly improved by VNG group. Our data suggests that the use of VNG leads to a faster regeneration process and a better functional recovery, although the final results are comparable to those of the NNG. VNG improve the quality of the axonal regeneration (axonal diameter and Schwann cells), although the increase in the axonal number is not significant and does not improve the long-term functional outcome.

Insight into 144 patients with ocular vascular events during VEGF antagonist injections

Directory of Open Access Journals (Sweden)

Shami M

2012-03-01

Full Text Available Ahmad M Mansour1, Maha Shahin2, Peter K Kofoed3, Maurizio B Parodi4, Michel Shami5, Stephen G Schwartz6, Collaborative Anti-VEGF Ocular Vascular Complications GroupDepartment of Ophthalmology, 1American University of Beirut, Beirut, Lebanon, Rafic Hariri University Hospital, Beirut, Lebanon; 2Mansoura University, Mansoura City, Egypt; 3Glostrup Hospital, University of Copenhagen, Denmark, National Eye Clinic, Kennedy Center, Glostrup, Denmark; 4University Vita-Salute, Scientific Institute San Raffaele, Milan, Italy; 5Texas Tech University Health Sciences Center, Lubbock, TX, USA; 6Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Naples and Miami, FL, USAAim: To record ocular vascular events following injections of vascular endothelium growth factor (VEGF antagonists.Methods: Collaborative multicenter case series (48 cases, literature reviews (32 cases, and reports to the FDA (64 cases of patients that had vascular occlusions during anti-VEGF therapy were collected and analyzed.Results: A total of 144 cases of ocular vascular events were identified, with these diagnosed a median of 15 days after anti-VEGF injection. The majority of patients had pre-existing risk factors for cardiovascular events and nine patients had a prior history of glaucoma. Mean visual acuity dropped by 6.4 lines with severe visual loss after injection to NLP (five eyes, LP (six eyes, and HM (two eyes. The overall risk of ocular vascular events following a VEGF antagonist injection was 0.108% in the general population and 2.61% in the diabetic population. Mean retinal arterial constriction after intravitreal bevacizumab in 13 eyes was 21% (standard deviation = 27%, and mean retinal venous constriction was 8% (standard deviation = 30%.Conclusion: Ocular vascular events are rare during anti-VEGF therapy, but can lead to severe visual loss and may be caused by a number of factors including the vasoconstrictor effect of the drug, a post-injection rise

Inherited thrombophilia and pregnancy loss. Study of an Argentinian cohort.

Science.gov (United States)

Perés Wingeyer, Silvia; Aranda, Federico; Udry, Sebastián; Latino, José; de Larrañaga, Gabriela

2018-03-06

Thrombophilia might increase the risk of suffering from obstetric complications by adversely affecting the normal placental vascular function. Our aim was to study the distributions of five thrombosis-associated genetic variants: factor V Leiden, prothrombin G20210A, -675 4G/5G PAI-1, 10034C/T gamma fibrinogen and 7872C/T factor XI and the frequencies of the deficiencies of protein C, S and antithrombin in Argentinian patients with recurrent pregnancy loss (RPL) and, therefore, to analyse their association with the risk and timing of RPL and the risk of suffering other vascular obstetric pathologies. We performed a case-control study that included 247 patients with idiopathic RPL (cases), 107 fertile controls and 224 subjects from general population (reference group). Cases were stratified according to the gestational time of the losses (early RPL, n = 89; late losses, n = 158; foetal losses, n = 107) and according to the type of vascular obstetric pathologies. No differences were found in the distribution of the genetic variants among RPL group vs. control/reference group (p >.05). Similarly, no differences were observed in their distributions when analysing RPL patients stratified according to gestational times or vascular obstetric pathologies (p >.05), except for the factor V Leiden carriage in patients with foetal growth retardation vs. controls (11.8%, 4/34 vs. 1.9%, 2/107; p = .04) (OR = 7.11 [1.24-40.93], p = .03). Factor V Leiden might have a significant impact on certain obstetric pathologies such as foetal growth retardation. The genetic variants, 10034C/T gamma fibrinogen and 7872C/T factor XI, associated with thromboembolic disease, would not have an impact on PRE. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

Treatment of the diabetic foot from a vascular surgeon's viewpoint.

Science.gov (United States)

Chang, B B; Shah, D M; Darling, R C; Leather, R P

1993-11-01

Diabetic foot lesions are caused by neurologic, orthopaedic, immunologic, and vascular derangements. Whereas some lesions may be initially caused by trauma and others directly caused by vascular disease, improvement of arterial perfusion often plays an important role in the successful salvage of these limbs. Fortunately, in the last several years, there has been a major improvement in the identification and treatment of those patients in whom correction of arterial occlusive disease is necessary for healing.

Retinal vascular segmentation using superpixel-based line operator and its application to vascular topology estimation.

Science.gov (United States)

Na, Tong; Xie, Jianyang; Zhao, Yitian; Zhao, Yifan; Liu, Yue; Wang, Yongtian; Liu, Jiang

2018-05-09

Automatic methods of analyzing of retinal vascular networks, such as retinal blood vessel detection, vascular network topology estimation, and arteries/veins classification are of great assistance to the ophthalmologist in terms of diagnosis and treatment of a wide spectrum of diseases. We propose a new framework for precisely segmenting retinal vasculatures, constructing retinal vascular network topology, and separating the arteries and veins. A nonlocal total variation inspired Retinex model is employed to remove the image intensity inhomogeneities and relatively poor contrast. For better generalizability and segmentation performance, a superpixel-based line operator is proposed as to distinguish between lines and the edges, thus allowing more tolerance in the position of the respective contours. The concept of dominant sets clustering is adopted to estimate retinal vessel topology and classify the vessel network into arteries and veins. The proposed segmentation method yields competitive results on three public data sets (STARE, DRIVE, and IOSTAR), and it has superior performance when compared with unsupervised segmentation methods, with accuracy of 0.954, 0.957, and 0.964, respectively. The topology estimation approach has been applied to five public databases (DRIVE,STARE, INSPIRE, IOSTAR, and VICAVR) and achieved high accuracy of 0.830, 0.910, 0.915, 0.928, and 0.889, respectively. The accuracies of arteries/veins classification based on the estimated vascular topology on three public databases (INSPIRE, DRIVE and VICAVR) are 0.90.9, 0.910, and 0.907, respectively. The experimental results show that the proposed framework has effectively addressed crossover problem, a bottleneck issue in segmentation and vascular topology reconstruction. The vascular topology information significantly improves the accuracy on arteries/veins classification. © 2018 American Association of Physicists in Medicine.

A novel vascular-targeting peptide for gastric cancer delivers low-dose TNFα to normalize the blood vessels and improve the anti-cancer efficiency of 5-fluorouracil.

Science.gov (United States)

Lu, Lan; Li, Zhi Jie; Li, Long Fei; Shen, Jing; Zhang, Lin; Li, Ming Xing; Xiao, Zhan Gang; Wang, Jian Hao; Cho, Chi Hin

2017-11-01

Various vascular-targeted agents fused with tumor necrosis factor α (TNFα) have been shown to improve drug absorption into tumor tissues and enhance tumor vascular function. TCP-1 is a peptide selected through in vivo phage library biopanning against a mouse orthotopic colorectal cancer model and is a promising agent for drug delivery. This study further investigated the targeting ability of TCP-1 phage and peptide to blood vessels in an orthotopic gastric cancer model in mice and assessed the synergistic anti-cancer effect of 5-fluorouracil (5-FU) with subnanogram TNFα targeted delivered by TCP-1 peptide. In vivo phage targeting assay and in vivo colocalization analysis were carried out to test the targeting ability of TCP-1 phage/peptide. A targeted therapy for improvement of the therapeutic efficacy of 5-FU and vascular function was performed through administration of TCP-1/TNFα fusion protein in this model. TCP-1 phage exhibited strong homing ability to the orthotopic gastric cancer after phage injection. Immunohistochemical staining suggested that and TCP-1 phage/TCP-1 peptide could colocalize with tumor vascular endothelial cells. TCP-1/TNFα combined with 5-FU was found to synergistically inhibit tumor growth, induce apoptosis and reduce cell proliferation without evident toxicity. Simultaneously, subnanogram TCP-1/TNFα treatment normalized tumor blood vessels. Targeted delivery of low-dose TNFα by TCP-1 peptide can potentially modulate the vascular function of gastric cancer and increase the drug delivery of chemotherapeutic drugs. Copyright © 2017. Published by Elsevier Inc.

Low-energy extracorporeal shock wave therapy promotes vascular endothelial growth factor expression and improves locomotor recovery after spinal cord injury.

Science.gov (United States)

Yamaya, Seiji; Ozawa, Hiroshi; Kanno, Haruo; Kishimoto, Koshi N; Sekiguchi, Akira; Tateda, Satoshi; Yahata, Kenichiro; Ito, Kenta; Shimokawa, Hiroaki; Itoi, Eiji

2014-12-01

Extracorporeal shock wave therapy (ESWT) is widely used for the clinical treatment of various human diseases. Recent studies have demonstrated that low-energy ESWT upregulates the expression of vascular endothelial growth factor (VEGF) and promotes angiogenesis and functional recovery in myocardial infarction and peripheral artery disease. Many previous reports suggested that VEGF produces a neuroprotective effect to reduce secondary neural tissue damage after spinal cord injury (SCI). The purpose of the present study was to investigate whether low-energy ESWT promotes VEGF expression and neuroprotection and improves locomotor recovery after SCI. Sixty adult female Sprague-Dawley rats were randomly divided into 4 groups: sham group (laminectomy only), sham-SW group (low-energy ESWT applied after laminectomy), SCI group (SCI only), and SCI-SW group (low-energy ESWT applied after SCI). Thoracic spinal cord contusion injury was inflicted using an impactor. Low-energy ESWT was applied to the injured spinal cord 3 times a week for 3 weeks. Locomotor function was evaluated using the Basso, Beattie, and Bresnahan (BBB) Scale (open field locomotor score) at different time points over 42 days after SCI. Hematoxylin and eosin staining was performed to assess neural tissue damage in the spinal cord. Neuronal loss was investigated by immunostaining for NeuN. The mRNA expressions of VEGF and its receptor, Flt-1, in the spinal cord were assessed using real-time polymerase chain reaction. Immunostaining for VEGF was performed to evaluate VEGF protein expression in the spinal cord. In both the sham and sham-SW groups, no animals showed locomotor impairment on BBB scoring. Histological analysis of H & E and NeuN stainings in the sham-SW group confirmed that no neural tissue damage was induced by the low-energy ESWT. Importantly, animals in the SCI-SW group demonstrated significantly better locomotor improvement than those in the SCI group at 7, 35, and 42 days after injury (p

Judicious use of ethanol embolization to improve the curative rate of vascular malformations

International Nuclear Information System (INIS)

Wang Jingbing; Fan Xindong; Cheng Yongde

2010-01-01

The incidence of vascular malformations is very low, and its clinical manifestations are infinite in variety, from an asymptomatic birthmark to life-threatening massive bleeding, even to congestive heart failure. The pathogenesis of vascular malformations is still unknown, therefore, its effective treatment is a real challenge. With the development of interventional technology and the accumulation of clinical experience in ethanol embolization, in local direct puncture injection and in endovascular embolization, the ethanol embolization will hopefully become the therapy of first choice for this kind of complicate and intractable disorders. (authors)

Modification of high saturated fat diet with n-3 polyunsaturated fat improves glucose intolerance and vascular dysfunction

Science.gov (United States)

Lamping, KL; Nuno, DW; Coppey, LJ; Holmes, AJ; Hu, S; Oltman, CL; Norris, AW; Yorek, MA

2013-01-01

Aims The ability of dietary enrichment with monounsaturated (MUFA), n-3, or n-6 polyunsaturated fatty acids (PUFA) to reverse glucose intolerance and vascular dysfunction resulting from excessive dietary saturated fatty acids is not resolved. We hypothesized that partial replacement of dietary saturated fats with n-3 PUFA enriched menhaden oil (MO) would provide greater improvement in glucose tolerance and vascular function compared to n-6 enriched safflower oil (SO) or MUFA-enriched olive oil (OO). Material and Methods We fed mice a high saturated fat diet (60% kcal from lard) for 12 weeks before substituting half the lard with MO, SO or OO for an additional 4 weeks. At the end of 4 weeks, we assessed glucose tolerance, insulin signaling and reactivity of isolated pressurized gracilis arteries. Results After 12 weeks of saturated fat diet, body weights were elevated and glucose tolerance abnormal compared to mice on control diet (13% kcal lard). Diet substituted with MO restored basal glucose levels, glucose tolerance, and indices of insulin signaling (phosphorylated Akt) to normal whereas restoration was limited for SO and OO substitutions. Although dilation to acetylcholine was reduced in arteries from mice on HF, OO and SO diets compared to normal diet, dilation to acetylcholine was fully restored and constriction to phenylephrine reduced in MO fed mice compared to normal. Conclusion We conclude that short term enrichment of an ongoing high fat diet with n-3 PUFA rich MO but not MUFA rich OO or n-6 PUFA rich SO reverses glucose tolerance, insulin signaling, and vascular dysfunction. PMID:22950668

Amiloride Improves Endothelial Function and Reduces Vascular Stiffness in Female Mice Fed a Western Diet

Directory of Open Access Journals (Sweden)

Luis A. Martinez-Lemus

2017-06-01

Full Text Available Obese premenopausal women lose their sex related cardiovascular disease protection and develop greater arterial stiffening than age matched men. In female mice, we have shown that consumption of a Western diet (WD, high in fat and refined sugars, is associated with endothelial dysfunction and vascular stiffening, which occur via activation of mineralocorticoid receptors and associated increases in epithelial Na+ channel (ENaC activity on endothelial cells (EnNaC. Herein our aim was to determine the effect that reducing EnNaC activity with a very-low-dose of amiloride would have on decreasing endothelial and arterial stiffness in young female mice consuming a WD. To this end, we fed female mice either a WD or control diet and treated them with or without a very-low-dose of the ENaC-inhibitor amiloride (1 mg/kg/day in the drinking water for 20 weeks beginning at 4 weeks of age. Mice consuming a WD were heavier and had greater percent body fat, proteinuria, and aortic stiffness as assessed by pulse-wave velocity than those fed control diet. Treatment with amiloride did not affect body weight, body composition, blood pressure, urinary sodium excretion, or insulin sensitivity, but significantly reduced the development of endothelial and aortic stiffness, aortic fibrosis, aortic oxidative stress, and mesenteric resistance artery EnNaC abundance and proteinuria in WD-fed mice. Amiloride also improved endothelial-dependent vasodilatory responses in the resistance arteries of WD-fed mice. These results indicate that a very-low-dose of amiloride, not affecting blood pressure, is sufficient to improve endothelial function and reduce aortic stiffness in female mice fed a WD, and suggest that EnNaC-inhibition may be sufficient to ameliorate the pathological vascular stiffening effects of WD-induced obesity in females.

Incremental value of a genetic risk score for the prediction of new vascular events in patients with clinically manifest vascular disease.

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Weijmans, Maaike; de Bakker, Paul I W; van der Graaf, Yolanda; Asselbergs, Folkert W; Algra, Ale; Jan de Borst, Gert; Spiering, Wilko; Visseren, Frank L J

2015-04-01

Several genetic markers are related to incidence of cardiovascular events. We evaluated whether a genetic risk score (GRS) based on 30 single-nucleotide-polymorphisms associated with coronary artery disease (CAD) can improve prediction of 10-year risk of new cardiovascular events in patients with clinical manifest vascular disease. In 5742 patients with symptomatic vascular disease enrolled in the SMART study, we developed Cox regression models based on the SMART Risk Score (SRS) and based on the SRS plus the GRS in all patients, in patients with a history of acute arterial thrombotic events and in patients with a history of more stable atherosclerosis and without CAD. The discriminatory ability was expressed by the c-statistic. Model calibration was evaluated by calibration plots. The incremental value of adding the GRS was assessed by net reclassification index (NRI) and decision curve analysis. During a median follow-up of 6.5 years (IQR4.0-9.5), the composite outcome of myocardial infarction, stroke, or vascular death occurred in 933 patients. Hazard ratios of GRS ranging from 0.86 to 1.35 were observed. The discriminatory capacity of the SRS for prediction of 10-year risk of cardiovascular events was fairly good (c-statistic 0.70, 95%CI 0.68-0.72), similar to the model based on the SRS plus the GRS. Calibration of the models based on SRS and SRS plus GRS was adequate. No increase in c-statistics, categorical NRIs and decision curves was observed when adding the GRS. The continuous NRI improved only in patients with stable atherosclerosis (0.14, 95%CI 0.03-0.25), increasing further excluding patients with a history of CAD (0.21, 95%CI 0.06-0.36). In patients with symptomatic vascular disease, a GRS did not improve risk prediction of 10-year risk of cardiovascular events beyond clinical characteristics. The GRS might improve risk prediction of first vascular events in the subgroup of patients with a history of stable atherosclerosis. Copyright © 2015 Elsevier

Surface modification and endothelialization of biomaterials as potential scaffolds for vascular tissue engineering applications.

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Ren, Xiangkui; Feng, Yakai; Guo, Jintang; Wang, Haixia; Li, Qian; Yang, Jing; Hao, Xuefang; Lv, Juan; Ma, Nan; Li, Wenzhong

2015-08-07

Surface modification and endothelialization of vascular biomaterials are common approaches that are used to both resist the nonspecific adhesion of proteins and improve the hemocompatibility and long-term patency of artificial vascular grafts. Surface modification of vascular grafts using hydrophilic poly(ethylene glycol), zwitterionic polymers, heparin or other bioactive molecules can efficiently enhance hemocompatibility, and consequently prevent thrombosis on artificial vascular grafts. However, these modified surfaces may be excessively hydrophilic, which limits initial vascular endothelial cell adhesion and formation of a confluent endothelial lining. Therefore, the improvement of endothelialization on these grafts by chemical modification with specific peptides and genes is now arousing more and more interest. Several active peptides, such as RGD, CAG, REDV and YIGSR, can be specifically recognized by endothelial cells. Consequently, graft surfaces that are modified by these peptides can exhibit targeting selectivity for the adhesion of endothelial cells, and genes can be delivered by targeting carriers to specific tissues to enhance the promotion and regeneration of blood vessels. These methods could effectively accelerate selective endothelial cell recruitment and functional endothelialization. In this review, recent developments in the surface modification and endothelialization of biomaterials in vascular tissue engineering are summarized. Both gene engineering and targeting ligand immobilization are promising methods to improve the clinical outcome of artificial vascular grafts.

Improvement of cell infiltration in electrospun polycaprolactone scaffolds for the construction of vascular grafts.

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Wang, Kai; Zhu, Meifeng; Li, Ting; Zheng, Wenting; Li, Li; Xu, Mian; Zhao, Qiang; Kong, Deling; Wang, Lianyong

2014-08-01

The less-than-ideal cell infiltration resulting from inherently small pore size limits the application of electrospinning scaffold in tissue engineering and regeneration medicine. The present study aims to develop a porogenic method which can significantly increase pore size in electrospinning scaffold and enhance cell migration. With this method, composite scaffolds consisting of poly(epsilon-caprolactone) (PCL) fibers and poly(ethylene oxide) (PEO) microparticles were prepared by simultaneously electrospinning and electrospraying. Removal of the PEO microparticles from the composites generated large pores. In vitro culture of NIH3T3 cells and in vivo subcutaneous implantation both demonstrated that the porogenic scaffolds markedly facilitated cell infiltration. With the same technique, vascular grafts with alternative dense and loose layers were prepared by turning on or off electrospraying PEO. SEM showed that there was no a clear delamination between the loose and dense layers. The mechanical strength and burst pressure of these vascular grafts could meet the requirements of vascular implantation. In conclusion, electrospinning PCL fibers with electrospraying PEO microparticles may be an effective and controllable method to increase pore size in electrospinning scaffold and provides a useful tool for the fabrication of vascular grafts that meets the need of blood vessel replacement.

The vascular basement membrane as "soil" in brain metastasis.

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W Shawn Carbonell

2009-06-01

Full Text Available Brain-specific homing and direct interactions with the neural substance are prominent hypotheses for brain metastasis formation and a modern manifestation of Paget's "seed and soil" concept. However, there is little direct evidence for this "neurotropic" growth in vivo. In contrast, many experimental studies have anecdotally noted the propensity of metastatic cells to grow along the exterior of pre-existing vessels of the CNS, a process termed vascular cooption. These observations suggest the "soil" for malignant cells in the CNS may well be vascular, rather than neuronal. We used in vivo experimental models of brain metastasis and analysis of human clinical specimens to test this hypothesis. Indeed, over 95% of early micrometastases examined demonstrated vascular cooption with little evidence for isolated neurotropic growth. This vessel interaction was adhesive in nature implicating the vascular basement membrane (VBM as the active substrate for tumor cell growth in the brain. Accordingly, VBM promoted adhesion and invasion of malignant cells and was sufficient for tumor growth prior to any evidence of angiogenesis. Blockade or loss of the beta1 integrin subunit in tumor cells prevented adhesion to VBM and attenuated metastasis establishment and growth in vivo. Our data establishes a new understanding of CNS metastasis formation and identifies the neurovasculature as the critical partner for such growth. Further, we have elucidated the mechanism of vascular cooption for the first time. These findings may help inform the design of effective molecular therapies for patients with fatal CNS malignancies.

Vascular input function correction of inflow enhancement for improved pharmacokinetic modeling of liver DCE-MRI.

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Ning, Jia; Schubert, Tilman; Johnson, Kevin M; Roldán-Alzate, Alejandro; Chen, Huijun; Yuan, Chun; Reeder, Scott B

2018-06-01

To propose a simple method to correct vascular input function (VIF) due to inflow effects and to test whether the proposed method can provide more accurate VIFs for improved pharmacokinetic modeling. A spoiled gradient echo sequence-based inflow quantification and contrast agent concentration correction method was proposed. Simulations were conducted to illustrate improvement in the accuracy of VIF estimation and pharmacokinetic fitting. Animal studies with dynamic contrast-enhanced MR scans were conducted before, 1 week after, and 2 weeks after portal vein embolization (PVE) was performed in the left portal circulation of pigs. The proposed method was applied to correct the VIFs for model fitting. Pharmacokinetic parameters fitted using corrected and uncorrected VIFs were compared between different lobes and visits. Simulation results demonstrated that the proposed method can improve accuracy of VIF estimation and pharmacokinetic fitting. In animal study results, pharmacokinetic fitting using corrected VIFs demonstrated changes in perfusion consistent with changes expected after PVE, whereas the perfusion estimates derived by uncorrected VIFs showed no significant changes. The proposed correction method improves accuracy of VIFs and therefore provides more precise pharmacokinetic fitting. This method may be promising in improving the reliability of perfusion quantification. Magn Reson Med 79:3093-3102, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Early Weight Loss with Liraglutide 3.0 mg Predicts 1-Year Weight Loss and is Associated with Improvements in Clinical Markers.

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Fujioka, Ken; O'Neil, Patrick M; Davies, Melanie; Greenway, Frank; C W Lau, David; Claudius, Birgitte; Skjøth, Trine Vang; Bjørn Jensen, Christine; P H Wilding, John

2016-11-01

To identify an early response criterion for predicting ≥5% weight loss with liraglutide 3.0 mg at week 56 and to compare efficacy outcomes in early responders (ERs) and early nonresponders (ENRs). Using pooled data from the SCALE Obesity and Prediabetes and SCALE Diabetes trials, weight loss of ≥4% at 16 weeks best predicted ≥5% weight loss after 56 weeks. Weight loss and changes in cardiometabolic risk factors and health-related quality of life were evaluated in ERs (≥4% weight loss at week 16) and ENRs (3.0 mg were 77.3%/22.7% (individuals without type 2 diabetes, T2D) and 62.7%/37.3% (those with T2D). Greater mean weight loss was observed in ERs versus ENRs: 10.8% versus 3.0% (without T2D) and 8.5% versus 3.1% (T2D). In both trials, greater proportions of ERs versus ENRs achieved ≥5%, >10%, and >15% weight loss at week 56 with liraglutide 3.0 mg. Greater improvements in cardiometabolic risk factors and health-related quality of life scores were observed in ERs versus ENRs. The early response criterion was clinically useful to identify individuals who would achieve clinically meaningful weight loss at 56 weeks. © 2016 The Authors Obesity published by Wiley Periodicals, Inc. on behalf of The Obesity Society (TOS).

Plasmalemma Vesicle-Associated Protein Has a Key Role in Blood-Retinal Barrier Loss

NARCIS (Netherlands)

Wisniewska-Kruk, Joanna; van der Wijk, Anne-Eva; van Veen, Henk A.; Gorgels, Theo G. M. F.; Vogels, Ilse M. C.; Versteeg, Danielle; van Noorden, Cornelis J. F.; Schlingemann, Reinier O.; Klaassen, Ingeborg

2016-01-01

Loss of blood-retinal barrier (BRB) properties induced by vascular endothelial growth factor (VEGF) and other factors is an important cause of diabetic macular edema. Previously, we found that the presence of plasmalemma vesicle-associated protein (PLVAP) in retinal capillaries associates with loss

Loss-Aversion or Loss-Attention: The Impact of Losses on Cognitive Performance

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Yechiam, Eldad; Hochman, Guy

2013-01-01

Losses were found to improve cognitive performance, and this has been commonly explained by increased weighting of losses compared to gains (i.e., loss aversion). We examine whether effects of losses on performance could be modulated by two alternative processes: an attentional effect leading to increased sensitivity to task incentives; and a…

Clinical application of the amplatzer vascular plug in the embolization of vascular malformations associated with congenital heart diseasee

International Nuclear Information System (INIS)

Pan Xin; Wang Cheng; Lu Jing; Wu Weihua; Fang Weiyi

2009-01-01

Objective: To evaluate the clinical efficacy of percutaneous transcatheter embolization by using Amplatzer vascular plug (AVP) for the treatment of vascular malformations associated with congenital heart diseases. Methods: During the period of June 2006-June 2008, 12 patients with congenital heart disease accompanied by vascular malformations received transcatheter occlusion of the anomalous vessels with AVP. The vascular malformations included solitary or multiple saccular pulmonary arteriovenous malformation (n = 7), coronary artery fistula (n = 2) and major aortopulmonary collaterals concomitant with severe Fallot' s tetralogy (n = 3). All patients were screened with transthoracic echocardiography (TTE) and thoracic CT angiography (CTA), and all the diagnoses were confirmed by routine cardioangiography. Results: Transcatheter occlusion of vascular malformations with AVP was successfully accomplished in all 12 patients. An angiographic check immediately after the procedure showed that complete occlusion was obtained in all patients and no embolism,migration or residual shunt were seen. Sixteen anomalous vessels were occluded. The mean internal diameter of these vessels was (5.2 ± 1.9) mm,while the mean diameter of AVP used was (9.2 ± 2.4) mm. After the operation (mean 3 months), the follow-up echocardiography and/or thoracic CT angiography showed that in all patients the occlusion remained in satisfactory condition and no residual shunt was found. Conclusions: Percutaneous transcatheter closure of congenital vascular malformations with AVP is technically feasible and clinically effective, this treatment can markedly improve patient's living quality and it is well worth extending its clinical application. (authors)

Comparative Genomics Yields Insights into Niche Adaptation of Plant Vascular Wilt Pathogens

NARCIS (Netherlands)

Klosterman, S.J.; Subbarao, K.V.; Kang, S.; Veronese, P.; Gold, S.E.; Thomma, B.P.H.J.; Chen, Z.J.; Henrissat, B.; Lee, Y.H.; Park, J.; Garcia-Pedrajas, M.D.; Barbara, D.J.; Anchieta, A.; Jonge, de R.; Santhanam, P.; Maruthachalam, K.; Atallah, Z.; Amyotte, S.G.; Paz, Z.; Inderbitzin, P.; Hayes, R.J.; Heiman, D.I.; Young, S.; Zeng, Q.; Engels, R.; Galagan, J.; Cuomo, C.; Dobinson, K.F.; Ma, L.J.

2011-01-01

The vascular wilt fungi Verticillium dahliae and V. albo-atrum infect over 200 plant species, causing billions of dollars in annual crop losses. The characteristic wilt symptoms are a result of colonization and proliferation of the pathogens in the xylem vessels, which undergo fluctuations in

Potential benefits of exercise on blood pressure and vascular function.

Science.gov (United States)

Pal, Sebely; Radavelli-Bagatini, Simone; Ho, Suleen

2013-01-01

Physical activity seems to enhance cardiovascular fitness during the course of the lifecycle, improve blood pressure, and is associated with decreased prevalence of hypertension and coronary heart disease. It may also delay or prevent age-related increases in arterial stiffness. It is unclear if specific exercise types (aerobic, resistance, or combination) have a better effect on blood pressure and vascular function. This review was written based on previous original articles, systematic reviews, and meta-analyses indexed on PubMed from years 1975 to 2012 to identify studies on different types of exercise and the associations or effects on blood pressure and vascular function. In summary, aerobic exercise (30 to 40 minutes of training at 60% to 85% of predicted maximal heart rate, most days of the week) appears to significantly improve blood pressure and reduce augmentation index. Resistance training (three to four sets of eight to 12 repetitions at 10 repetition maximum, 3 days a week) appears to significantly improve blood pressure, whereas combination exercise training (15 minutes of aerobic and 15 minutes of resistance, 5 days a week) is beneficial to vascular function, but at a lower scale. Aerobic exercise seems to better benefit blood pressure and vascular function. Copyright © 2013 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

Group-based exercise combined with dual-task training improves gait but not vascular health in active older adults without dementia.

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Gregory, Michael A; Gill, Dawn P; Zou, Guangyong; Liu-Ambrose, Teresa; Shigematsu, Ryosuke; Fitzgerald, Clara; Hachinski, Vladimir; Shoemaker, Kevin; Petrella, Robert J

2016-01-01

Gait abnormalities and vascular disease risk factors are associated with cognitive impairment in aging. To determine the impact of group-based exercise and dual-task training on gait and vascular health, in active community-dwelling older adults without dementia. Participants [n=44, mean (SD) age: 73.5 (7.2) years, 68% female] were randomized to either intervention (exercise+dual-task; EDT) or control (exercise only; EO). Each week, for 26 weeks, both groups accumulated 50 or 75 min of aerobic exercise from group-based classes and 45 min of beginner-level square stepping exercise (SSE). Participants accumulating only 50 min of aerobic exercise were instructed to participate in an additional 25 min each week outside of class. The EDT group also answered cognitively challenging questions while performing SSE (i.e., dual-task training). The effect of the interventions on gait and vascular health was compared between groups using linear mixed effects models. At 26 weeks, the EDT group demonstrated increased dual-task (DT) gait velocity [difference between groups in mean change from baseline (95% CI): 0.29 m/s (0.16-0.43), pexercise combined with dual-task training can improve DT gait characteristics in active older adults without dementia. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Early kidney allograft loss - is there scope for improvement?

Science.gov (United States)

Ferrari, Paolo

2018-02-17

Increased longevity matching using Kidney Donor Profile Index (KDPI) to optimize long-term kidney allograft survival has been central to the effort of appropriate allocation of deceased donor kidneys. The data by Helenterä and co-workers in this issue, who looked at predictors of early allograft loss, should prompt an analysis of whether predictors of short-term graft survival can improve KDPI-based decisions when considering whether to accept or decline a deceased donor kidney offer. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Early Weight Loss with Liraglutide 3.0 mg Predicts 1‐Year Weight Loss and is Associated with Improvements in Clinical Markers

Science.gov (United States)

O'Neil, Patrick M.; Davies, Melanie; Greenway, Frank; C.W. Lau, David; Claudius, Birgitte; Skjøth, Trine Vang; Bjørn Jensen, Christine; P.H. Wilding, John

2016-01-01

Objective To identify an early response criterion for predicting ≥5% weight loss with liraglutide 3.0 mg at week 56 and to compare efficacy outcomes in early responders (ERs) and early nonresponders (ENRs). Methods Using pooled data from the SCALE Obesity and Prediabetes and SCALE Diabetes trials, weight loss of ≥4% at 16 weeks best predicted ≥5% weight loss after 56 weeks. Weight loss and changes in cardiometabolic risk factors and health‐related quality of life were evaluated in ERs (≥4% weight loss at week 16) and ENRs (3.0 mg were 77.3%/22.7% (individuals without type 2 diabetes, T2D) and 62.7%/37.3% (those with T2D). Greater mean weight loss was observed in ERs versus ENRs: 10.8% versus 3.0% (without T2D) and 8.5% versus 3.1% (T2D). In both trials, greater proportions of ERs versus ENRs achieved ≥5%, >10%, and >15% weight loss at week 56 with liraglutide 3.0 mg. Greater improvements in cardiometabolic risk factors and health‐related quality of life scores were observed in ERs versus ENRs. Conclusions The early response criterion was clinically useful to identify individuals who would achieve clinically meaningful weight loss at 56 weeks. PMID:27804269

The use of acoustically tuned resonators to improve the sound transmission loss of double panel partitions

Science.gov (United States)

Mason, J. M.; Fahy, F. J.

1986-10-01

The effectiveness of tuned Helmholtz resonators connected to the partition cavity in double-leaf partitions utilized in situations requiring low weight structures with high transmission loss is investigated as a method of improving sound transmission loss. This is demonstrated by a simple theoretical model and then experimentally verified. Results show that substantial improvements may be obtained at and around the mass-air-mass frequency for a total resonator volume 15 percent of the cavity volume.

Predicting core losses and efficiency of SRM in continuous current mode of operation using improved analytical technique

International Nuclear Information System (INIS)

Parsapour, Amir; Dehkordi, Behzad Mirzaeian; Moallem, Mehdi

2015-01-01

In applications in which the high torque per ampere at low speed and rated power at high speed are required, the continuous current method is the best solution. However, there is no report on calculating the core loss of SRM in continuous current mode of operation. Efficiency and iron loss calculation which are complex tasks in case of conventional mode of operation is even more involved in continuous current mode of operation. In this paper, the Switched Reluctance Motor (SRM) is modeled using finite element method and core loss and copper loss of SRM in discontinuous and continuous current modes of operation are calculated using improved analytical techniques to include the minor loop losses in continuous current mode of operation. Motor efficiency versus speed in both operation modes is obtained and compared. - Highlights: • Continuous current method for Switched Reluctance Motor (SRM) is explained. • An improved analytical technique is presented for SRM core loss calculation. • SRM losses in discontinuous and continuous current operation modes are presented. • Effect of mutual inductances on SRM performance is investigated

Predicting core losses and efficiency of SRM in continuous current mode of operation using improved analytical technique

Energy Technology Data Exchange (ETDEWEB)

Parsapour, Amir, E-mail: amirparsapour@gmail.com [Department of Electrical Engineering, University of Isfahan, Isfahan (Iran, Islamic Republic of); Dehkordi, Behzad Mirzaeian, E-mail: mirzaeian@eng.ui.ac.ir [Department of Electrical Engineering, University of Isfahan, Isfahan (Iran, Islamic Republic of); Moallem, Mehdi, E-mail: moallem@cc.iut.ac.ir [Department of Electrical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of)

2015-03-15

In applications in which the high torque per ampere at low speed and rated power at high speed are required, the continuous current method is the best solution. However, there is no report on calculating the core loss of SRM in continuous current mode of operation. Efficiency and iron loss calculation which are complex tasks in case of conventional mode of operation is even more involved in continuous current mode of operation. In this paper, the Switched Reluctance Motor (SRM) is modeled using finite element method and core loss and copper loss of SRM in discontinuous and continuous current modes of operation are calculated using improved analytical techniques to include the minor loop losses in continuous current mode of operation. Motor efficiency versus speed in both operation modes is obtained and compared. - Highlights: • Continuous current method for Switched Reluctance Motor (SRM) is explained. • An improved analytical technique is presented for SRM core loss calculation. • SRM losses in discontinuous and continuous current operation modes are presented. • Effect of mutual inductances on SRM performance is investigated.

Endothelial dysfunction in metabolic and vascular disorders.

Science.gov (United States)

Polovina, Marija M; Potpara, Tatjana S

2014-03-01

Vascular endothelium has important regulatory functions in the cardiovascular system and a pivotal role in the maintenance of vascular health and metabolic homeostasis. It has long been recognized that endothelial dysfunction participates in the pathogenesis of atherosclerosis from early, preclinical lesions to advanced, thrombotic complications. In addition, endothelial dysfunction has been recently implicated in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Considering that states of insulin resistance (eg, metabolic syndrome, impaired fasting glucose, impaired glucose tolerance, and T2DM) represent the most prevalent metabolic disorders and risk factors for atherosclerosis, it is of considerable scientific and clinical interest that both metabolic and vascular disorders have endothelial dysfunction as a common background. Importantly, endothelial dysfunction has been associated with adverse outcomes in patients with established cardiovascular disease, and a growing body of evidence indicates that endothelial dysfunction also imparts adverse prognosis in states of insulin resistance. In this review, we discuss the association of insulin resistance and T2DM with endothelial dysfunction and vascular disease, with a focus on the underlying mechanisms and prognostic implications of the endothelial dysfunction in metabolic and vascular disorders. We also address current therapeutic strategies for the improvement of endothelial dysfunction.

Improving Technology for Vascular Imaging

Science.gov (United States)

Rana, Raman

Neuro-endovascular image guided interventions (Neuro-EIGIs) is a minimally invasive procedure that require micro catheters and endovascular devices be inserted into the vasculature via an incision near the femoral artery and guided under low dose fluoroscopy to the vasculature of the head and neck. However, the endovascular devices used for the purpose are of very small size (stents are of the order of 50mum to 100mum) and the success of these EIGIs depends a lot on the accurate placement of these devices. In order to accurately place these devices inside the patient, the interventionalist should be able to see them clearly. Hence, high resolution capabilities are of immense importance in neuro-EIGIs. The high-resolution detectors, MAF-CCD and MAF-CMOS, at the Toshiba Stroke and Vascular Research Center at the University at Buffalo are capable of presenting improved images for better patient care. Focal spot of an x-ray tube plays an important role in performance of these high resolution detectors. The finite size of the focal spot results into the blurriness around the edges of the image of the object resulting in reduced spatial resolution. Hence, knowledge of accurate size of the focal spot of the x-ray tube is very essential for the evaluation of the total system performance. Importance of magnification and image detector blur deconvolution was demonstrated to carry out the more accurate measurement of x-ray focal spot using a pinhole camera. A 30 micron pinhole was used to obtain the focal spot images using flat panel detector (FPD) and different source to image distances (SIDs) were used to achieve different magnifications (3.16, 2.66 and 2.16). These focal spot images were deconvolved with a 2-D modulation transfer function (MTF), obtained using noise response (NR) method, to remove the detector blur present in the images. Using these corrected images, the accurate size of all the three focal spots were obtained and it was also established that effect of

Heterozygote loss of ACE2 is sufficient to increase the susceptibility to heart disease.

Science.gov (United States)

Wang, Wang; Patel, Vaibhav B; Parajuli, Nirmal; Fan, Dong; Basu, Ratnadeep; Wang, Zuocheng; Ramprasath, Tharmarajan; Kassiri, Zamaneh; Penninger, Josef M; Oudit, Gavin Y

2014-08-01

Angiotensin-converting enzyme 2 (ACE2) metabolizes Ang II into Ang 1-7 thereby negatively regulating the renin-angiotensin system. However, heart disease in humans and in animal models is associated with only a partial loss of ACE2. ACE2 is an X-linked gene; and as such, we tested the clinical relevance of a partial loss of ACE2 by using female ACE2(+/+) (wildtype) and ACE2(+/-) (heterozygote) mice. Pressure overload in ACE2(+/-) mice resulted in greater LV dilation and worsening systolic and diastolic dysfunction. These changes were associated with increased myocardial fibrosis, hypertrophy, and upregulation of pathological gene expression. In response to Ang II infusion, there was increased NADPH oxidase activity and myocardial fibrosis resulting in the worsening of Ang II-induced diastolic dysfunction with a preserved systolic function. Ang II-mediated cellular effects in cultured adult ACE2(+/-) cardiomyocytes and cardiofibroblasts were exacerbated. Ang II-mediated pathological signaling worsened in ACE2(+/-) hearts characterized by an increase in the phosphorylation of ERK1/2 and JNK1/2 and STAT-3 pathways. The ACE2(+/-) mice showed an exacerbated pressor response with increased vascular fibrosis and stiffness. Vascular superoxide and nitrotyrosine levels were increased in ACE2(+/-) vessels consistent with increased vascular oxidative stress. These changes occurred with increased renal fibrosis and superoxide production. Partial heterozygote loss of ACE2 is sufficient to increase the susceptibility to heart disease secondary to pressure overload and Ang II infusion. Heart disease in humans with idiopathic dilated cardiomyopathy is associated with a partial loss of ACE2. Heterozygote female ACE2 mutant mice showed enhanced susceptibility to pressure overload-induced heart disease. Heterozygote female ACE2 mutant mice showed enhanced susceptibility to Ang II-induced heart and vascular diseases. Partial loss of ACE2 is sufficient to enhance the susceptibility to

Does the location of a vascular loop in the cerebellopontine angle explain pulsatile and non-pulsatile tinnitus?

International Nuclear Information System (INIS)

Nowe, V.; Wang, X.L.; Gielen, J.; Goethem, J.Van; Oezsarlak, Oe.; De Schepper, A.M.; Parizel, P.M.; Ridder, D. De; Heyning, P.H.Van de

2004-01-01

The purpose was to investigate patients with unexplained pulsatile and non-pulsatile tinnitus by means of MR imaging of the cerebellopontine angle (CPA) and to correlate the clinical subtype of tinnitus with the location of a blood vessel (in the internal auditory canal or at the cisternal part of the VIIIth cranial nerve). Clinical presentation of tinnitus and perceptive hearing loss were correlated. In 47 patients with unexplained tinnitus, an MR examination of the CPA was performed. Virtual endoscopy reconstructions were obtained using a 3D axial thin-section high-resolution heavily T2-weighted gradient echo constructive interference in steady state (CISS) data-set. High-resolution T2-weighted CISS images showed a significantly higher number of vascular loops in the internal auditory canal in patients with arterial pulsatile tinnitus compared to patients with non-pulsatile tinnitus (P<0.00001). Virtual endoscopy images were used to investigate vascular contacts at the cisternal part of the VIIIth cranial nerve in patients with low pitch and high pitch non-pulsatile tinnitus. A significantly different distribution of the vascular contacts (P=0.0320) was found. Furthermore, a correlation between the clinical presentation of non-pulsatile tinnitus (high pitch and low pitch) and the perceptive hearing loss was found (P=0.0235). High-resolution heavily T2-weighted CISS images and virtual endoscopy of the CPA can be used to evaluate whether a vascular contact is present in the internal auditory canal or at the cisternal part of the VIIIth cranial nerve and whether the location of the vascular contact correlates with the clinical subtype of tinnitus. Our findings suggest that there is a tonotopical structure of the cisternal part of the VIIIth cranial nerve. A correlation between the clinical presentation of tinnitus and hearing loss was found. (orig.)

Does the location of a vascular loop in the cerebellopontine angle explain pulsatile and non-pulsatile tinnitus?

Energy Technology Data Exchange (ETDEWEB)

Nowe, V; Wang, X L; Gielen, J; Goethem, J Van; Oezsarlak, Oe; De Schepper, A M; Parizel, P M [University of Antwerp, Department of Radiology, Edegem (Belgium); Ridder, D De [University of Antwerp, Department of Neurosurgery, Edegem (Belgium); Heyning, P.H.Van de [University of Antwerp, Department of Otorhinolaryngology, Edegem (Belgium)

2004-12-01

The purpose was to investigate patients with unexplained pulsatile and non-pulsatile tinnitus by means of MR imaging of the cerebellopontine angle (CPA) and to correlate the clinical subtype of tinnitus with the location of a blood vessel (in the internal auditory canal or at the cisternal part of the VIIIth cranial nerve). Clinical presentation of tinnitus and perceptive hearing loss were correlated. In 47 patients with unexplained tinnitus, an MR examination of the CPA was performed. Virtual endoscopy reconstructions were obtained using a 3D axial thin-section high-resolution heavily T2-weighted gradient echo constructive interference in steady state (CISS) data-set. High-resolution T2-weighted CISS images showed a significantly higher number of vascular loops in the internal auditory canal in patients with arterial pulsatile tinnitus compared to patients with non-pulsatile tinnitus (P<0.00001). Virtual endoscopy images were used to investigate vascular contacts at the cisternal part of the VIIIth cranial nerve in patients with low pitch and high pitch non-pulsatile tinnitus. A significantly different distribution of the vascular contacts (P=0.0320) was found. Furthermore, a correlation between the clinical presentation of non-pulsatile tinnitus (high pitch and low pitch) and the perceptive hearing loss was found (P=0.0235). High-resolution heavily T2-weighted CISS images and virtual endoscopy of the CPA can be used to evaluate whether a vascular contact is present in the internal auditory canal or at the cisternal part of the VIIIth cranial nerve and whether the location of the vascular contact correlates with the clinical subtype of tinnitus. Our findings suggest that there is a tonotopical structure of the cisternal part of the VIIIth cranial nerve. A correlation between the clinical presentation of tinnitus and hearing loss was found. (orig.)

[Premorbid psychological processes in patients with Alzheimer's disease and in patients with vascular dementia].

Science.gov (United States)

Bauer, J; Stadtmüller, G; Qualmann, J; Bauer, H

1995-01-01

We analyzed the premorbid biographies of 21 patients with Alzheimer's disease for possible common features. Eleven age-matched patients suffering from vascular dementia served as a control group. The observations from our qualitative study indicate that persons with a conflict-avoiding, submissive, premorbid personality predominate among Alzheimer patients. Persons who later became Alzheimer patients tended to leave important daily-life decisions to their partners (or other persons of reference). Prior to the onset of the very first neuropsychological deficits, persons who later became Alzheimer patients were found to stay in a lasting situation in which they were subject to a treatment that could be designated as "caring tutelage." Subsequently, most patients became subject to an increasingly patronizing and restricting treatment. Further elements that were frequently found as part of the premorbid development were physical or psychological burden, loss of social contacts, and loss of motivation. In contrast, assertive and dominant premorbid traits predominated in the group of vascular patients. The premorbid biographical situation of persons who later became vascular patients was characterized by a loss of the control which these persons had hitherto exerted over partners, their families, or the situation at their working place. We advance the hypothesis that in Alzheimer's disease the described psychological phenomena are part of a preclinical process, during which biological, psychological, and social factors interact, finally joining into the clinical stage of the disease. Possibilities for psychotherapeutic interventions are discussed.

Glio-vascular changes during ageing in wild-type and Alzheimer's disease-like APP/PS1 mice.

Science.gov (United States)

Janota, C S; Brites, D; Lemere, C A; Brito, M A

2015-09-16

Vascular and glial involvement in the development of neurodegenerative disorders, such as Alzheimer's disease (AD), and age-related brain vulnerabilities have been suggested. Therefore, we sought to: (i) investigate which vascular and glial events are evident in ageing and/or AD, (ii) to establish the temporal evolution of vascular and glial changes in AD-like and wild-type (WT) mice and (iii) to relate them to amyloid-β (Aβ) peptide accumulation. We examined immunohistochemically hippocampi and cortex from APP/PS1dE9 and WT C57BL/6 mice along ageing and disease progression (young-adulthood, middle- and old-age). Ageing resulted in the increase in receptor for advanced glycation endproducts expression, as well as the entrance of thrombin and albumin in hippocampal parenchyma. In contrast, the loss of platelet-derived growth factor receptor-β (PDGFR-β) positive cells, in both regions, was only related to AD pathogenesis. Hypovascularization was affected by both ageing and AD in the hippocampus, but resulted from the interaction between both factors in the cortex. Astrogliosis was a result of AD in hippocampus and of both factors in cortex, while microgliosis was associated with fibrillar amyloid plaques in AD-like mice and with the interaction between both factors in each of the studied regions. In sum, these data show that senile plaques precede vascular and glial alterations only in hippocampus, whereas in cortex, vascular and glial alterations, namely the loss of PDGFR-β-positive cells and astrogliosis, accompanied the first senile plaques. Hence, this study points to vascular and glial events that co-exist in AD pathogenesis and age-related brain vulnerabilities. Copyright © 2015 Elsevier B.V. All rights reserved.

Electrospinning thermoplastic polyurethane/graphene oxide scaffolds for small diameter vascular graft applications

Energy Technology Data Exchange (ETDEWEB)

Jing, Xin [National Engineering Research Center of Novel Equipment for Polymer Processing, The Key Laboratory of Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou (China); Department of Mechanical Engineering, University of Wisconsin–Madison, WI (United States); Wisconsin Institute for Discovery, University of Wisconsin–Madison, WI (United States); Mi, Hao-Yang [National Engineering Research Center of Novel Equipment for Polymer Processing, The Key Laboratory of Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou (China); Salick, Max R. [Wisconsin Institute for Discovery, University of Wisconsin–Madison, WI (United States); Department of Engineering Physics, University of Wisconsin–Madison, WI (United States); Cordie, Travis M. [Wisconsin Institute for Discovery, University of Wisconsin–Madison, WI (United States); Department of Biomedical Engineering, University of Wisconsin–Madison, WI (United States); Peng, Xiang-Fang, E-mail: pmxfpeng@scut.edu.cn [National Engineering Research Center of Novel Equipment for Polymer Processing, The Key Laboratory of Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou (China); Turng, Lih-Sheng, E-mail: turng@engr.wisc.edu [Department of Mechanical Engineering, University of Wisconsin–Madison, WI (United States); Wisconsin Institute for Discovery, University of Wisconsin–Madison, WI (United States)

2015-04-01

Fabrication of small diameter vascular grafts plays an important role in vascular tissue engineering. In this study, thermoplastic polyurethane (TPU)/graphene oxide (GO) scaffolds were fabricated via electrospinning at different GO contents as potential candidates for small diameter vascular grafts. In terms of mechanical and surface properties, the tensile strength, Young's modulus, and hydrophilicity of the scaffolds increased with an increase of GO content while plasma treatment dramatically improved the scaffold hydrophilicity. Mouse fibroblast (3T3) and human umbilical vein endothelial cells (HUVECs) were cultured on the scaffolds separately to study their biocompatibility and potential to be used as vascular grafts. It was found that cell viability for both types of cells, fibroblast proliferation, and HUVEC attachment were the highest at a 0.5 wt.% GO loading whereas oxygen plasma treatment also enhanced HUVEC viability and attachment significantly. In addition, the suture retention strength and burst pressure of tubular TPU/GO scaffolds containing 0.5 wt.% GO were found to meet the requirements of human blood vessels, and endothelial cells were able to attach to the inner surface of the tubular scaffolds. Platelet adhesion tests using mice blood indicated that vascular scaffolds containing 0.5% GO had low platelet adhesion and activation. Therefore, the electrospun TPU/GO tubular scaffolds have the potential to be used in vascular tissue engineering. - Highlights: • TPU/GO vascular scaffolds were prepared via electrospinning. • The addition of GO improved the modulus and hydrophilicity of the scaffolds. • Fibroblast cell culture verified the scaffolds' biocompatibility. • Endothelial cell culture verified the scaffolds' vascular graft affinity. • The mechanical properties fulfilled the requirements of vascular grafts.

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

Science.gov (United States)

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.

Self-Condensation Culture Enables Vascularization of Tissue Fragments for Efficient Therapeutic Transplantation

Directory of Open Access Journals (Sweden)

Yoshinobu Takahashi

2018-05-01

Full Text Available Summary: Clinical transplantation of tissue fragments, including islets, faces a critical challenge because of a lack of effective strategies that ensure efficient engraftment through the timely integration of vascular networks. We recently developed a complex organoid engineering method by “self-condensation” culture based on mesenchymal cell-dependent contraction, thereby enabling dissociated heterotypic lineages including endothelial cells to self-organize in a spatiotemporal manner. Here, we report the successful adaptation of this method for generating complex tissues from diverse tissue fragments derived from various organs, including pancreatic islets. The self-condensation of human and mouse islets with endothelial cells not only promoted functionalization in culture but also massively improved post-transplant engraftment. Therapeutically, fulminant diabetic mice were more efficiently treated by a vascularized islet transplant compared with the conventional approach. Given the general limitations of post-transplant vascularization associated with 3D tissue-based therapy, our approach offers a promising means of enhancing efficacy in the context of therapeutic tissue transplantation. : Takahashi et al. report on generating vascularized islet tissue from humans and mice. After transplantation, vascularized islets significantly improve survival of diabetic mice, demonstrating the quick normalization of blood glucose compared with conventional islet transplantation. Keywords: tissue engineering, tissue-based therapy, vascularization, islet transplantation, organoid

Phase-based vascular input function: Improved quantitative DCE-MRI of atherosclerotic plaques

NARCIS (Netherlands)

van Hoof, R. H. M.; Hermeling, E.; Truijman, M. T. B.; van Oostenbrugge, R. J.; Daemen, J. W. H.; van der Geest, R. J.; van Orshoven, N. P.; Schreuder, A. H.; Backes, W. H.; Daemen, M. J. A. P.; Wildberger, J. E.; Kooi, M. E.

2015-01-01

Purpose: Quantitative pharmacokinetic modeling of dynamic contrast-enhanced (DCE)-MRI can be used to assess atherosclerotic plaque microvasculature, which is an important marker of plaque vulnerability. Purpose of the present study was (1) to compare magnitude-versus phase-based vascular input

Vascular Wall-Resident Multipotent Stem Cells of Mesenchymal Nature within the Process of Vascular Remodeling: Cellular Basis, Clinical Relevance, and Implications for Stem Cell Therapy.

Science.gov (United States)

Klein, Diana

2016-01-01

Until some years ago, the bone marrow and the endothelial cell compartment lining the vessel lumen (subendothelial space) were thought to be the only sources providing vascular progenitor cells. Now, the vessel wall, in particular, the vascular adventitia, has been established as a niche for different types of stem and progenitor cells with the capacity to differentiate into both vascular and nonvascular cells. Herein, vascular wall-resident multipotent stem cells of mesenchymal nature (VW-MPSCs) have gained importance because of their large range of differentiation in combination with their distribution throughout the postnatal organism which is related to their existence in the adventitial niche, respectively. In general, mesenchymal stem cells, also designated as mesenchymal stromal cells (MSCs), contribute to the maintenance of organ integrity by their ability to replace defunct cells or secrete cytokines locally and thus support repair and healing processes of the affected tissues. This review will focus on the central role of VW-MPSCs within vascular reconstructing processes (vascular remodeling) which are absolute prerequisite to preserve the sensitive relationship between resilience and stability of the vessel wall. Further, a particular advantage for the therapeutic application of VW-MPSCs for improving vascular function or preventing vascular damage will be discussed.

Inner Ear Conductive Hearing Loss and Unilateral Pulsatile Tinnitus Associated with a Dural Arteriovenous Fistula: Case Based Review and Analysis of Relationship between Intracranial Vascular Abnormalities and Inner Ear Fluids

Directory of Open Access Journals (Sweden)

Ettore Cassandro

2015-01-01

Full Text Available While pulsatile tinnitus (PT and dural arteriovenous fistula (DAVF are not rarely associated, the finding of a conductive hearing loss (CHL in this clinical picture is unusual. Starting from a case of CHL and PT, diagnosed to be due to a DAVF, we analyzed relationship between intracranial vascular abnormalities and inner ear fluids. DAVF was treated with endovascular embolization. Following this, there was a dramatic recovery of PT and of CHL, confirming their cause-effect link with DAVF. We critically evaluated the papers reporting this association. This is the first case of CHL associated with PT and DAVF. We describe the most significant experiences and theories reported in literature, with a personal analysis about the possible relationship between vascular intracranial system and labyrinthine fluids. In conclusion, we believe that this association may be a challenge for otolaryngologists. So we suggest to consider the possibility of a DAVF or other AVMs when PT is associated with CHL, without alterations of tympanic membrane and middle ear tests.

VA Vascular Injury Study (VAVIS): VA-DoD extremity injury outcomes collaboration.

Science.gov (United States)

Shireman, Paula K; Rasmussen, Todd E; Jaramillo, Carlos A; Pugh, Mary Jo

2015-02-03

Limb injuries comprise 50-60% of U.S. Service member's casualties of wars in Afghanistan and Iraq. Combat-related vascular injuries are present in 12% of this cohort, a rate 5 times higher than in prior wars. Improvements in medical and surgical trauma care, including initial in-theatre limb salvage approaches (IILS) have resulted in improved survival and fewer amputations, however, the long-term outcomes such as morbidity, functional decline, and risk for late amputation of salvaged limbs using current process of care have not been studied. The long-term care of these injured warfighters poses a significant challenge to the Department of Defense (DoD) and Department of Veterans Affairs (VA). The VA Vascular Injury Study (VAVIS): VA-DoD Extremity Injury Outcomes Collaborative, funded by the VA, Health Services Research and Development Service, is a longitudinal cohort study of Veterans with vascular extremity injuries. Enrollment will begin April, 2015 and continue for 3 years. Individuals with a validated extremity vascular injury in the Department of Defense Trauma Registry will be contacted and will complete a set of validated demographic, social, behavioral, and functional status measures during interview and online/ mailed survey. Primary outcome measures will: 1) Compare injury, demographic and geospatial characteristics of patients with IILS and identify late vascular surgery related limb complications and health care utilization in Veterans receiving VA vs. non-VA care, 2) Characterize the preventive services received by individuals with vascular repair and related outcomes, and 3) Describe patient-reported functional outcomes in Veterans with traumatic vascular limb injuries. This study will provide key information about the current process of care for Active Duty Service members and Veterans with polytrauma/vascular injuries at risk for persistent morbidity and late amputation. The results of this study will be the first step for clinicians in VA and

Evaluation and percutaneous management of atherosclerotic peripheral vascular disease

International Nuclear Information System (INIS)

Widlus, D.M.; Osterman, F.A. Jr.

1989-01-01

Atherosclerotic peripheral vascular disease (PVD) of the lower extremities deprives a person of the ability to exercise to their satisfaction, later of the ability to perform the activities of their daily life, and finally of their legs themselves. Peripheral vascular disease has long been managed by the vascular surgeon utilizing endarterectomy and peripheral arterial bypass. Patient acceptance of nonsurgical, percutaneous procedures such as percutaneous transluminal balloon angioplasty (PTA) is high. Increased utilization of these procedures has led to improved techniques and adjuncts to therapy, as well as more critical review of long-term results. This article will review the evaluation and nonoperative management of PVD, with an emphasis on the newer modalities of management presently being investigated

Improved Path Loss Simulation Incorporating Three-Dimensional Terrain Model Using Parallel Coprocessors

Directory of Open Access Journals (Sweden)

Zhang Bin Loo

2017-01-01

Full Text Available Current network simulators abstract out wireless propagation models due to the high computation requirements for realistic modeling. As such, there is still a large gap between the results obtained from simulators and real world scenario. In this paper, we present a framework for improved path loss simulation built on top of an existing network simulation software, NS-3. Different from the conventional disk model, the proposed simulation also considers the diffraction loss computed using Epstein and Peterson’s model through the use of actual terrain elevation data to give an accurate estimate of path loss between a transmitter and a receiver. The drawback of high computation requirements is relaxed by offloading the computationally intensive components onto an inexpensive off-the-shelf parallel coprocessor, which is a NVIDIA GPU. Experiments are performed using actual terrain elevation data provided from United States Geological Survey. As compared to the conventional CPU architecture, the experimental result shows that a speedup of 20x to 42x is achieved by exploiting the parallel processing of GPU to compute the path loss between two nodes using terrain elevation data. The result shows that the path losses between two nodes are greatly affected by the terrain profile between these two nodes. Besides this, the result also suggests that the common strategy to place the transmitter in the highest position may not always work.

Pediatric vascular access

International Nuclear Information System (INIS)

Donaldson, James S.

2006-01-01

Pediatric interventional radiologists are ideally suited to provide vascular access services to children because of inherent safety advantages and higher success from using image-guided techniques. The performance of vascular access procedures has become routine at many adult interventional radiology practices, but this service is not as widely developed at pediatric institutions. Although interventional radiologists at some children's hospitals offer full-service vascular access, there is little or none at others. Developing and maintaining a pediatric vascular access service is a challenge. Interventionalists skilled in performing such procedures are limited at pediatric institutions, and institutional support from clerical staff, nursing staff, and technologists might not be sufficiently available to fulfill the needs of such a service. There must also be a strong commitment by all members of the team to support such a demanding service. There is a slippery slope of expected services that becomes steeper and steeper as the vascular access service grows. This review is intended primarily as general education for pediatric radiologists learning vascular access techniques. Additionally, the pediatric or adult interventional radiologist seeking to expand services might find helpful tips. The article also provides education for the diagnostic radiologist who routinely interprets radiographs containing vascular access devices. (orig.)

Valproic acid reduces hair loss and improves survival in patients receiving temozolomide-based radiation therapy for high-grade glioma.

Science.gov (United States)

Watanabe, Shinichi; Kuwabara, Yui; Suehiro, Satoshi; Yamashita, Daisuke; Tanaka, Mamoru; Tanaka, Akihiro; Ohue, Shiro; Araki, Hiroaki

2017-03-01

Valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, is also used to manage seizures in glioblastoma patients. HDAC inhibitors can protect normal cells and tissues from the deleterious effects of radiotherapy, and VPA is reported to improve the survival of glioblastoma patients receiving chemoradiation therapy. VPA also promotes hair growth, and thus has the potential to reduce the radiotherapy side effect of hair loss while improving the survival of patients with glioblastoma. The purpose of this study was to determine whether VPA use during radiotherapy for high-grade glioma is associated with decreased side effects of radiotherapy and an improvement in overall survival (OS) and progression-free survival (PFS). Medical records of 112 patients with high-grade glioma were retrospectively reviewed. We grouped patients by VPA use or non-use during radiotherapy, and evaluated hair loss, OS, and PFS. The radiation dose and fractionation at the onset of hair loss were 4 Gy and two fractions higher, respectively, in the VPA group compared with the VPA non-use group (P hair loss and improvement in survival. Hair loss prevention benefits patients suffering from the deleterious effects of radiation.

Reciprocal effects of exercise and nutrition treatment-induced weight loss with improved body image and physical self-concept.

Science.gov (United States)

Annesi, James J; Porter, Kandice J

2015-01-01

Improvements in self-image and mood are often reported as outcomes of obesity interventions. However, they may also concurrently influence weight loss, suggesting a reciprocal effect. Although previously reported for overweight women, such relationships were untested in morbidly obese women whose psychosocial responses to treatment may be different, and health-risks greater. Women (N = 161, Meanage = 42 years) with morbid obesity (MeanBMI = 45.1 kg/m(2)) participated in a 6-month, behaviorally based physical activity and nutrition treatment. Significant within-group improvements in weight-loss behaviors (physical activity and eating), weight, body satisfaction, physical self-concept, and depression were found. After controlling for age, mediation analyses indicated that, as a result of the treatment, weight loss was both an outcome and mediator of improvements in body-areas satisfaction and physical self-concept (reciprocal effects), but not depression. Results replicated findings from women with lower degrees of overweight, and suggested that weight-loss treatments emphasize changes in self-perception.

Practical alternatives to chronic caloric restriction for optimizing vascular function with ageing

Science.gov (United States)

Seals, Douglas R.

2016-01-01

Abstract Calorie restriction (CR) in the absence of malnutrition exerts a multitude of physiological benefits with ageing in model organisms and in humans including improvements in vascular function. Despite the well‐known benefits of chronic CR, long‐term energy restriction is not likely to be a feasible healthy lifestyle strategy in humans due to poor sustained adherence, and presents additional concerns if applied to normal weight older adults. This review summarizes what is known about the effects of CR on vascular function with ageing including the underlying molecular ‘energy‐ and nutrient‐sensing’ mechanisms, and discusses the limited but encouraging evidence for alternative pharmacological and lifestyle interventions that may improve vascular function with ageing by mimicking the beneficial effects of long‐term CR. PMID:27641062

Improved loss calculations for the HDM magnets

International Nuclear Information System (INIS)

Mallick, G.T. Jr.; Carr, W.J.; Krefta, M.P.; Johnson, D.

1994-01-01

Losses due to ramped fields and currents, quite adequate for the initial design, were calculated previously by Snitchler, Jayakumar, Kovachev, and Orrell for the high energy booster magnets to be used in the SSC. The present analysis considers the loss problem in more detail

Vascular Tissue Engineering: Effects of Integrating Collagen into a PCL Based Nanofiber Material

Directory of Open Access Journals (Sweden)

Ulf Bertram

2017-01-01

Full Text Available The engineering of vascular grafts is a growing field in regenerative medicine. Although numerous attempts have been made, the current vascular grafts made of polyurethane (PU, Dacron®, or Teflon® still display unsatisfying results. Electrospinning of biopolymers and native proteins has been in the focus of research to imitate the extracellular matrix (ECM of vessels to produce a small caliber, off-the-shelf tissue engineered vascular graft (TEVG as a substitute for poorly performing PU, Dacron, or Teflon prostheses. Blended poly-ε-caprolactone (PCL/collagen grafts have shown promising results regarding biomechanical and cell supporting features. In order to find a suitable PCL/collagen blend, we fabricated plane electrospun PCL scaffolds using various collagen type I concentrations ranging from 5% to 75%. We analyzed biocompatibility and morphological aspects in vitro. Our results show beneficial features of collagen I integration regarding cell viability and functionality, but also adverse effects like the loss of a confluent monolayer at high concentrations of collagen. Furthermore, electrospun PCL scaffolds containing 25% collagen I seem to be ideal for engineering vascular grafts.

Vascular Augmentation in Renal Transplantation: Supercharging and Turbocharging

Directory of Open Access Journals (Sweden)

Euicheol C. Jeong

2017-05-01

Full Text Available The most common anatomic variant seen in donor kidneys for renal transplantation is the presence of multiple renal arteries, which can cause an increased risk of complications. Accessory renal arteries should be anastomosed to the proper source arteries to improve renal perfusion via the appropriate vascular reconstruction techniques. In microsurgery, 2 kinds of vascular augmentation methods, known as ‘supercharging’ and ‘turbocharging,’ have been introduced to ensure vascular perfusion in the transferred flap. Supercharging uses a distant source of the vessels, while turbocharging uses vascular sources within the same flap territory. These technical concepts can also be applied in renal transplantation, and in this report, we describe 2 patients who underwent procedures using supercharging and turbocharging. In one case, the ipsilateral deep inferior epigastric artery was transposed to the accessory renal artery (supercharging, and in the other case, the accessory renal artery was anastomosed to the corresponding main renal artery with a vascular graft (turbocharging. The transplanted kidneys showed good perfusion and proper function. No cases of renal failure, hypertension, rejection, or urologic complications were observed. These microsurgical techniques can be safely utilized for renal transplantation with donor kidneys that have multiple arteries with a lower complication rate and better outcome.

Vascular Augmentation in Renal Transplantation: Supercharging and Turbocharging.

Science.gov (United States)

Jeong, Euicheol C; Hwang, Seung Hwan; Eo, Su Rak

2017-05-01

The most common anatomic variant seen in donor kidneys for renal transplantation is the presence of multiple renal arteries, which can cause an increased risk of complications. Accessory renal arteries should be anastomosed to the proper source arteries to improve renal perfusion via the appropriate vascular reconstruction techniques. In microsurgery, 2 kinds of vascular augmentation methods, known as 'supercharging' and 'turbocharging,' have been introduced to ensure vascular perfusion in the transferred flap. Supercharging uses a distant source of the vessels, while turbocharging uses vascular sources within the same flap territory. These technical concepts can also be applied in renal transplantation, and in this report, we describe 2 patients who underwent procedures using supercharging and turbocharging. In one case, the ipsilateral deep inferior epigastric artery was transposed to the accessory renal artery (supercharging), and in the other case, the accessory renal artery was anastomosed to the corresponding main renal artery with a vascular graft (turbocharging). The transplanted kidneys showed good perfusion and proper function. No cases of renal failure, hypertension, rejection, or urologic complications were observed. These microsurgical techniques can be safely utilized for renal transplantation with donor kidneys that have multiple arteries with a lower complication rate and better outcome.

Carbon nanotubes as VEGF carriers to improve the early vascularization of porcine small intestinal submucosa in abdominal wall defect repair

Directory of Open Access Journals (Sweden)

Liu Z

2014-03-01

��MWNT–PSIS contributed to early vascularization from 2–12 weeks postimplantation and obtained more effective collagen deposition and exhibited improved tensile strength at 24 weeks postimplantation compared to PSIS or PSIS scaffolds, incorporating MWNT without VEGF165 loading (MWNT–PSIS. Keywords: vascular endothelial growth factor165, controlled release, multi-walled carbon nanotube, early vascularization

Music venues and hearing loss: Opportunities for and barriers to improving environmental conditions

NARCIS (Netherlands)

Vogel, I.; Ploeg, C.P.B. van der; Brug, J.; Raat, H.

2009-01-01

This study explores the opportunities for and barriers to improving environmental conditions in order to reduce the risk for music-induced hearing loss in people who attend music venues. Individual semi-structured interviews were held with 20 representatives of music venues and of governmental

Vascular responses to radiotherapy and androgendeprivation therapy in experimental prostate cancer

LENUS (Irish Health Repository)

2012-05-23

AbstractBackgroundRadiotherapy (RT) and androgen-deprivation therapy (ADT) are standard treatments for advanced prostate cancer (PC). Tumor vascularization is recognized as an important physiological feature likely to impact on both RT and ADT response, and this study therefore aimed to characterize the vascular responses to RT and ADT in experimental PC.MethodsUsing mice implanted with CWR22 PC xenografts, vascular responses to RT and ADT by castration were visualized in vivo by DCE MRI, before contrast-enhancement curves were analyzed both semi-quantitatively and by pharmacokinetic modeling. Extracted image parameters were correlated to the results from ex vivo quantitative fluorescent immunohistochemical analysis (qIHC) of tumor vascularization (9 F1), perfusion (Hoechst 33342), and hypoxia (pimonidazole), performed on tissue sections made from tumors excised directly after DCE MRI.ResultsCompared to untreated (Ctrl) tumors, an improved and highly functional vascularization was detected in androgen-deprived (AD) tumors, reflected by increases in DCE MRI parameters and by increased number of vessels (VN), vessel density ( VD), and vessel area fraction ( VF) from qIHC. Although total hypoxic fractions ( HF) did not change, estimated acute hypoxia scores ( AHS) – the proportion of hypoxia staining within 50 μm from perfusion staining – were increased in AD tumors compared to in Ctrl tumors. Five to six months after ADT renewed castration-resistant (CR) tumor growth appeared with an even further enhanced tumor vascularization. Compared to the large vascular changes induced by ADT, RT induced minor vascular changes. Correlating DCE MRI and qIHC parameters unveiled the semi-quantitative parameters area under curve ( AUC) from initial time-points to strongly correlate with VD and VF, whereas estimation of vessel size ( VS) by DCE MRI required pharmacokinetic modeling. HF was not correlated to any DCE MRI parameter, however, AHS may be estimated after

3-D Ultrasound Vascularity Assessment for Breast Cancer Diagnosis

National Research Council Canada - National Science Library

Carson, Paul

1997-01-01

This project is to improve the diagnosis and management of patients with breast cancer through development and evaluation of 3D ultrasound imaging and quantification techniques emphasizing vascularity...

Vitamin K status and vascular calcification: evidence from observational and clinical studies.

Science.gov (United States)

Shea, M Kyla; Holden, Rachel M

2012-03-01

Vascular calcification occurs when calcium accumulates in the intima (associated with atherosclerosis) and/or media layers of the vessel wall. Coronary artery calcification (CAC) reflects the calcium burden within the intima and media of the coronary arteries. In population-based studies, CAC independently predicts cardiovascular disease (CVD) and mortality. A preventive role for vitamin K in vascular calcification has been proposed based on its role in activating matrix Gla protein (MGP), a calcification inhibitor that is expressed in vascular tissue. Although animal and in vitro data support this role of vitamin K, overall data from human studies are inconsistent. The majority of population-based studies have relied on vitamin K intake to measure status. Phylloquinone is the primary dietary form of vitamin K and available supplementation trials, albeit limited, suggest phylloquinone supplementation is relevant to CAC. Yet observational studies have found higher dietary menaquinone, but not phylloquinone, to be associated with less calcification. Vascular calcification is highly prevalent in certain patient populations, especially in those with chronic kidney disease (CKD), and it is plausible vitamin K may contribute to reducing vascular calcification in patients at higher risk. Subclinical vitamin K deficiency has been reported in CKD patients, but studies linking vitamin K status to calcification outcomes in CKD are needed to clarify whether or not improving vitamin K status is associated with improved vascular health in CKD. This review summarizes the available evidence of vitamin K and vascular calcification in population-based studies and clinic-based studies, with a specific focus on CKD patients.

Vascular Access in Children

International Nuclear Information System (INIS)

Krishnamurthy, Ganesh; Keller, Marc S.

2011-01-01

Establishment of stable vascular access is one of the essential and most challenging procedures in a pediatric hospital. Many clinical specialties provide vascular service in a pediatric hospital. At the top of the “expert procedural pyramid” is the pediatric interventional radiologist, who is best suited and trained to deliver this service. Growing awareness regarding the safety and high success rate of vascular access using image guidance has led to increased demand from clinicians to provide around-the-clock vascular access service by pediatric interventional radiologists. Hence, the success of a vascular access program, with the pediatric interventional radiologist as the key provider, is challenging, and a coordinated multidisciplinary team effort is essential for success. However, there are few dedicated pediatric interventional radiologists across the globe, and also only a couple of training programs exist for pediatric interventions. This article gives an overview of the technical aspects of pediatric vascular access and provides useful tips for obtaining vascular access in children safely and successfully using image guidance.

Evaluation of a liquid embolization agent (Onyx) for transcatheter embolization for renal vascular lesions

Energy Technology Data Exchange (ETDEWEB)

Rennert, Janine; Herold, T.; Schreyer, A.G.; Jung, E.M.; Mueller-Wille, R.; Zorger, N. [Inst. fuer Roentgendiagnostik, Klinikum der Univ. Regensburg (Germany); Banas, B.; Feuerbach, S. [Medizinische Klinik, Nephrologie, Univ. Regensburg (Germany); Lenhart, M. [Klinik fuer Diagnostische und Interventionelle Radiologie, Sozialstiftung Bamberg (Germany)

2009-10-15

Purpose: to evaluate the therapeutic outcome after endovascular treatment of renal vascular lesions using the liquid embolization agent, Onyx. Materials and methods: between 2004 and 2008 nine patients with renal vascular lesions were treated with transcatheter arterial embolization using Onyx. The renal vascular lesions consisted of 4 AV-fistulas, a pseudoaneurysm, bleeding from a single subsegmental artery, diffuse parenchymal bleeding after trauma, septic embolizations and multiple aneurysms in endocarditis. All patients underwent selective angiography of the renal artery. A dimethyl sulfoxide (DMSO)-compatible microcatheter was used and Onyx was injected. The technical and clinical success rate, examination time and procedure-related complications were documented. Results: the overall technical and clinical success rate was 100%. One patient had to be treated twice due to recurrent bleeding after an accidental puncture with a drainage catheter. No loss of viable renal tissue occurred in 4 cases. In 4 patients mild to moderate parenchyma loss was noted. In one patient having diffuse renal bleeding, occlusion of the main renal artery was performed. No procedure-related complications were noted. The mean examination time was 16.17 min when treating with Onyx alone and 60 min when using a combination of Onyx and coils. Within an average follow-up period of 21 months, no recurrent renal bleeding or recurrent AV-fistulas occurred. Conclusion: Onyx is an effective embolization agent for the treatment of renal vascular lesions. It allows controlled and quick application with low complication rates and a short examination time as a standalone agent or in combination with coils. (orig.)

32 CFR 644.554 - Insurance against loss or damages to buildings and improvements by fire or acts of God.

Science.gov (United States)

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 true Insurance against loss or damages to buildings and improvements by fire or acts of God. 644.554 Section 644.554 National Defense Department of... Procedure § 644.554 Insurance against loss or damages to buildings and improvements by fire or acts of God...

Loss of cIAP1 attenuates soleus muscle pathology and improves diaphragm function in mdx mice

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Enwere, Emeka K.; Boudreault, Louise; Holbrook, Janelle; Timusk, Kristen; Earl, Nathalie; LaCasse, Eric; Renaud, Jean-Marc; Korneluk, Robert G.

2013-01-01

The cellular inhibitor of apoptosis 1 (cIAP1) protein is an essential regulator of canonical and noncanonical nuclear factor κB (NF-κB) signaling pathways. NF-κB signaling is known to play important roles in myogenesis and degenerative muscle disorders such as Duchenne muscular dystrophy (DMD), but the involvement of cIAP1 in muscle disease has not been studied directly. Here, we asked whether the loss of cIAP1 would influence the pathology of skeletal muscle in the mdx mouse model of DMD. Double-mutant cIAP1−/−;mdx mice exhibited reduced muscle damage and decreased fiber centronucleation in the soleus, compared with single-mutant cIAP1+/+;mdx mice. This improvement in pathology was associated with a reduction in muscle infiltration by macrophages and diminished expression of inflammatory cytokines such as IL-6 and tumor necrosis factor-α. Furthermore, the cIAP1−/−;mdx mice exhibited reduced serum creatine kinase, and improved exercise endurance associated with improved exercise resilience by the diaphragm. Mechanistically, the loss of cIAP1 was sufficient to drive constitutive activation of the noncanonical NF-κB pathway, which led to increased myoblast fusion in vitro and in vivo. Collectively, these results show that the loss of cIAP1 protects skeletal muscle from the degenerative pathology resulting from systemic loss of dystrophin. PMID:23184147

Oscillation of Angiogenesis and Vascular Dropout in Progressive Human Vascular Disease. [Vascular Pattern as Useful Read-Out of Complex Molecular Signaling

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Parsons-Wingerter, Patricia

2010-01-01

When analyzed by VESsel GENeration Analysis (VESGEN) software, vascular patterns provide useful integrative read-outs of complex, interacting molecular signaling pathways. Using VESGEN, we recently discovered and published our innovative, surprising findings that angiogenesis oscillated with vascular dropout throughout progression of diabetic retinopathy, a blinding vascular disease. Our findings provide a potential paradigm shift in the current prevailing view on progression and treatment of this disease, and a new early-stage window of regenerative therapeutic opportunities. The findings also suggest that angiogenesis may oscillate with vascular disease in a homeostatic-like manner during early stages of other inflammatory progressive diseases such as cancer and coronary vascular disease.

Expression of vascular endothelial growth factor in Juvenile Angiofibroma.

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Hota, Ashutosh; Sarkar, Chitra; Gupta, Siddhartha Datta; Kumar, Rakesh; Bhalla, Ashu Seith; Thakar, Alok

2015-06-01

To examine Juvenile Angiofibroma (JA) tissue for expression of vascular endothelial growth factor (VEGF), and to explore its relationship with puberty status, stage, recurrence and the intraoperative blood loss. Retrospective cohort study of 36 histologically proven cases of JA. Minimum follow up period was 3 years. VEGF expression on tumor cells assessed by immunohistochemistry and graded on two criteria--percentage of cells expressing positivity and the intensity of positivity. These two parameters assessed for impact on puberty status, stage, recurrence, and blood loss. VEGF expression noted on the tumor endothelial cells in 36/36, and on the tumor stromal cells in 34/36. The percentage of cells expressing VEGF and the intensity of expression were not significantly related to puberty status, tumor stage, recurrence, or intra-operative blood loss (p values 0.3-1.0). VEGF expression is near universal in JA. Such expression is independent of puberty status and stage, and does not impact on intra operative blood loss and recurrence. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

HNF1A variant, energy-reduced diets and insulin resistance improvement during weight loss: The POUNDS Lost trial and DIRECT.

Science.gov (United States)

Huang, Tao; Wang, Tiange; Heianza, Yoriko; Sun, Dianjianyi; Ivey, Kerry; Durst, Ronen; Schwarzfuchs, Dan; Stampfer, Meir J; Bray, George A; Sacks, Frank M; Shai, Iris; Qi, Lu

2018-06-01

To determine whether weight-loss diets varying in macronutrients modulate the genetic effect of hepatocyte nuclear factor 1α (HNF1A) rs7957197 on weight loss and improvement of insulin resistance. We analysed the interaction between HNF1A rs7957197 and weight-loss diets with regard to weight loss and insulin resistance improvement among 722 overweight/obese adults from a 2-year randomized weight-loss trial, the POUNDS Lost trial. The findings were replicated in another independent 2-year weight-loss trial, the Dietary Intervention Randomized Controlled Trial (DIRECT), in 280 overweight/obese adults. In the POUNDS Lost trial, we found that a high-fat diet significantly modified the genetic effect of HNF1A on weight loss and reduction in waist circumference (P for interaction = .006 and .005, respectively). Borderline significant interactions for fasting insulin and insulin resistance (P for interaction = .07 and .06, respectively) were observed. We replicated the results in DIRECT. Pooled results showed similar significant interactions with weight loss, waist circumference reduction, and improvement in fasting insulin and insulin resistance (P values for interaction = .001, .005, .02 and .03, respectively). Greater decreases in weight, waist circumference, fasting insulin level and insulin resistance were observed in participants with the T allele compared to those without the T allele in the high-fat diet group (P = .04, .03 and .01, respectively). Our replicable findings provide strong evidence that individuals with the HNF1A rs7957197 T allele might obtain more benefits in weight loss and improvement of insulin resistance by choosing a hypocaloric and high-fat diet. © 2018 John Wiley & Sons Ltd.

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

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Paulsen, S J; Miller, J S

2015-05-01

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

Ebselen by modulating oxidative stress improves hypoxia-induced macroglial Müller cell and vascular injury in the retina.

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Tan, Sih Min; Deliyanti, Devy; Figgett, William A; Talia, Dean M; de Haan, Judy B; Wilkinson-Berka, Jennifer L

2015-07-01

Oxidative stress is an important contributor to glial and vascular cell damage in ischemic retinopathies. We hypothesized that ebselen via its ability to reduce reactive oxygen species (ROS) and augment nuclear factor-like 2 (Nrf2) anti-oxidants would attenuate hypoxia-induced damage to macroglial Müller cells and also lessen retinal vasculopathy. Primary cultures of rat Müller cells were exposed to normoxia (21% O2), hypoxia (0.5% O2) and ebselen (2.5 μM) for up to 72 h. Oxygen-induced retinopathy (OIR) was induced in C57BL/6J mice while control mice were housed in room air. Mice received vehicle (saline, 5% dimethyl sulfoxide) or ebselen (10 mg/kg) each day between postnatal days 6-18. In cultured Müller cells, flow cytometry for dihydroethidium revealed that ebselen reduced the hypoxia-induced increase in ROS levels, whilst increasing the expression of Nrf2-regulated anti-oxidant genes, heme oxygenase 1, glutathione peroxidase-1, NAD(P)H dehydrogenase quinone oxidoreductase 1 and glutamate-cysteine ligase. Moreover, in Müller cells, ebselen reduced the hypoxia-induced increase in protein levels of pro-angiogenic and pro-inflammatory factors including vascular endothelial growth factor, interleukin-6, monocyte chemoattractant-protein 1 and intercellular adhesion molecule-1, and the mRNA levels of glial fibrillary acidic protein (GFAP), a marker of Müller cell injury. Ebselen improved OIR by attenuating capillary vaso-obliteration and neovascularization and a concomitant reduction in Müller cell gliosis and GFAP. We conclude that ebselen protects against hypoxia-induced injury of retinal Müller cells and the microvasculature, which is linked to its ability to reduce oxidative stress, vascular damaging factors and inflammation. Agents such as ebselen may be potential treatments for retinopathies that feature oxidative stress-mediated damage to glia and the microvasculature. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Vascular Calcification - Pathological Mechanism and Clinical Application - . Role of vascular smooth muscle cells in vascular calcification].

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Kurabayashi, Masahiko

2015-05-01

Vascular calcification is commonly seen with aging, chronic kidney disese (CKD), diabetes, and atherosclerosis, and is closely associated with cardiovascular morbidity and mortality. Vascular calcification has long been regarded as the final stage of degeneration and necrosis of arterial wall and a passive, unregulated process. However, it is now known to be an active and tightly regulated process involved with phenotypic transition of vascular smooth muscle cells (VSMC) that resembles bone mineralization. Briefly, calcium deposits of atherosclerotic plaque consist of hydroxyapatite and may appear identical to fully formed lamellar bone. By using a genetic fate mapping strategy, VSMC of the vascular media give rise to the majority of the osteochondrogenic precursor- and chondrocyte-like cells observed in the calcified arterial media of MGP (- / -) mice. Osteogenic differentiation of VSMC is characterized by the expression of bone-related molecules including bone morphogenetic protein (BMP) -2, Msx2 and osteopontin, which are produced by osteoblasts and chondrocytes. Our recent findings are that (i) Runx2 and Notch1 induce osteogenic differentiation, and (ii) advanced glycation end-product (AGE) /receptor for AGE (RAGE) and palmitic acid promote osteogenic differentiation of VSMC. To understand of the molecular mechanisms of vascular calcification is now under intensive research area.

Large scale serial two-photon microscopy to investigate local vascular changes in whole rodent brain models of Alzheimer's disease

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Delafontaine-Martel, P.; Lefebvre, J.; Damseh, R.; Castonguay, A.; Tardif, P.; Lesage, F.

2018-02-01

In this study, an automated serial two-photon microscope was used to image a fluorescent gelatin filled rodent's brain in 3D. A method to compute vascular density using automatic segmentation was combined with coregistration techniques to build group-level vasculature metrics. By studying the medial prefrontal cortex and the hippocampal formation of 3 age groups (2, 4.5 and 8 months old), we compared vascular density for both WT and an Alzheimer model transgenic brain (APP/PS1). We observe a loss of vascular density caused by the ageing process and we propose further analysis to confirm our results.

Detailed Vascular Anatomy of the Human Retina by Projection-Resolved Optical Coherence Tomography Angiography

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Campbell, J. P.; Zhang, M.; Hwang, T. S.; Bailey, S. T.; Wilson, D. J.; Jia, Y.; Huang, D.

2017-02-01

Optical coherence tomography angiography (OCTA) is a noninvasive method of 3D imaging of the retinal and choroidal circulations. However, vascular depth discrimination is limited by superficial vessels projecting flow signal artifact onto deeper layers. The projection-resolved (PR) OCTA algorithm improves depth resolution by removing projection artifact while retaining in-situ flow signal from real blood vessels in deeper layers. This novel technology allowed us to study the normal retinal vasculature in vivo with better depth resolution than previously possible. Our investigation in normal human volunteers revealed the presence of 2 to 4 distinct vascular plexuses in the retina, depending on location relative to the optic disc and fovea. The vascular pattern in these retinal plexuses and interconnecting layers are consistent with previous histologic studies. Based on these data, we propose an improved system of nomenclature and segmentation boundaries for detailed 3-dimensional retinal vascular anatomy by OCTA. This could serve as a basis for future investigation of both normal retinal anatomy, as well as vascular malformations, nonperfusion, and neovascularization.

[Vascular complications following kidney transplant: the role of color-Doppler imaging].

Science.gov (United States)

Granata, Antonio; Floccari, Fulvio; Lentini, Paolo; Vittoria, Salvatore; Di Pietro, Fabio; Zamboli, Pasquale; Fiorini, Fulvio; Fatuzzo, Pasquale

2012-01-01

The progressive decline in the incidence of graft rejection has made urological, surgical, parenchymal and vascular complications of kidney transplant more frequent. The latter, although accounting for only 5-10% of all post-transplant complications, are a frequent cause of graft loss. Ultrasonography, both in B-mode and with Doppler ultrasound, is an important diagnostic tool in case of clinical conditions which might impair kidney function. Even though ultrasonography is considered fundamental in the diagnosis of parenchymal and surgical complications of the transplanted kidney, its role is not fully understood in case of vascular complications of the graft. The specificity of Doppler ultrasound is very important in case of stenosis of the transplanted renal artery, pseudoaneurysms, arteriovenous fistulas, and thrombosis with complete or partial artery or vein occlusion. Doppler and color determinations present high diagnostic accuracy, which is higher in case of successive measurements performed during the follow-up of the graft. Modern techniques including contrast-enhanced ultrasound increase the diagnostic power of ultrasonography in case of vascular complications of the transplanted kidney, planted kidney.

The effects of chronic resveratrol treatment on vascular responsiveness of streptozotocin-induced diabetic rats.

Science.gov (United States)

Silan, Coskun

2008-05-01

Deficiency in the vasorelaxant capacity is a result of an oxidative stress in diabetic animals and seems to be an etiological factor of vascular complications of diabetes. The present study was designed to examine whether resveratrol (RSV), a polyphenolic compound which is naturally present in grape and red wine, has a protective effect on diabetic aorta. Resveratrol (5 mg/kg/d, i.p.) was administered for 42 d to streptozotocin (STZ) (60 mg/kg) induced diabetic rats. Loss of weight, hyperglycemia, and elevated levels of plasma malondialdehyde (MDA) were observed in diabetic rats. Resveratrol treatment was significantly effective for these metabolic and biochemical abnormalities. The contractile responses of the aorta were recorded. Compared with control subjects, the aorta showed significantly enhanced contractile responses to noradrenaline (NA), but not to potassium chloride (KCl), in diabetic rats. Treatment of diabetic rats with resveratrol significantly reversed the increases in responsiveness and sensitivity of aorta to noradrenaline. In diabetic aorta, the relaxation response to acetylcholine (Ach) was found to be significantly decreased compared with control subjects, and resveratrol treatment reversed this; no such change was observed in the relaxation response to sodium nitroprusside (SNP). These results indicated that resveratrol significantly improved not only glucose metabolism and oxidative injury but also impaired vascular responses in streptozotocin induced diabetic rats.

Uterine Vascular Lesions

Science.gov (United States)

Vijayakumar, Abhishek; Srinivas, Amruthashree; Chandrashekar, Babitha Moogali; Vijayakumar, Avinash

2013-01-01

Vascular lesions of the uterus are rare; most reported in the literature are arteriovenous malformations (AVMs). Uterine AVMs can be congenital or acquired. In recent years, there has been an increasing number of reports of acquired vascular lesions of the uterus following pregnancy, abortion, cesarean delivery, and curettage. It can be seen from these reports that there is confusion concerning the terminology of uterine vascular lesions. There is also a lack of diagnostic criteria and management guidelines, which has led to an increased number of unnecessary invasive procedures (eg, angiography, uterine artery embolization, hysterectomy for abnormal vaginal bleeding). This article familiarizes readers with various vascular lesions of the uterus and their management. PMID:24340126

Case report: Unilateral conduction hearing loss due to central venous occlusion.

Science.gov (United States)

Ribeiro, Phillip; Patel, Swetal; Qazi, Rizwan A

2016-05-07

Central venous stenosis is a well-known complication in patients with vascular access for hemodialysis. We report two cases involving patients on hemodialysis with arteriovenous fistulas who developed reversible unilateral conductive hearing loss secondary to critical stenosis of central veins draining the arteriovenous dialysis access. A proposed mechanism for the patients' reversible unilateral hearing loss is pterygoid venous plexus congestion leading to decreased Eustachian tube patency. Endovascular therapy was conducted to treat the stenosis and the hearing loss of both patients was returned to near normal after successful central venous angioplasty.

Ursodeoxycholic Acid Attenuates Endoplasmic Reticulum Stress-Related Retinal Pericyte Loss in Streptozotocin-Induced Diabetic Mice

Directory of Open Access Journals (Sweden)

Yoo-Ri Chung

2017-01-01

Full Text Available Loss of pericytes, an early hallmark of diabetic retinopathy (DR, results in breakdown of the blood-retinal barrier. Endoplasmic reticulum (ER stress may be involved in this process. The purpose of this study was to examine the effects of ursodeoxycholic acid (UDCA, a known ameliorator of ER stress, on pericyte loss in DR of streptozotocin- (STZ- induced diabetic mice. To assess the extent of DR, the integrity of retinal vessels and density of retinal capillaries in STZ-induced diabetic mice were evaluated. Additionally, induction of ER stress and the unfolded protein response (UPR were assessed in diabetic mice and human retinal pericytes exposed to advanced glycation end products (AGE or modified low-density lipoprotein (mLDL. Fluorescein dye leakage during angiography and retinal capillary density were improved in UDCA-treated diabetic mice, compared to the nontreated diabetic group. Among the UPR markers, those involved in the protein kinase-like ER kinase (PERK pathway were increased, while UDCA attenuated UPR in STZ-induced diabetic mice as well as AGE- or mLDL-exposed retinal pericytes in culture. Consequently, vascular integrity was improved and pericyte loss reduced in the retina of STZ-induced diabetic mice. Our findings suggest that UDCA might be effective in protecting against DR.

Connective tissue growth factor is involved in structural retinal vascular changes in long-term experimental diabetes

NARCIS (Netherlands)

Van Geest, Rob J; Leeuwis, Jan Willem; Dendooven, Amélie; Pfister, Frederick; Bosch, Klazien; Hoeben, Kees A; Vogels, Ilse M C; Van der Giezen, Dionne M; Dietrich, Nadine; Hammes, Hans-Peter; Goldschmeding, Roel; Klaassen, Ingeborg; Van Noorden, Cornelis J F; Schlingemann, Reinier O

Early retinal vascular changes in the development of diabetic retinopathy (DR) include capillary basal lamina (BL) thickening, pericyte loss and the development of acellular capillaries. Expression of the CCN (connective tissue growth factor/cysteine-rich 61/nephroblastoma overexpressed) family

Connective tissue growth factor is involved in structural retinal vascular changes in long-term experimental diabetes

NARCIS (Netherlands)

van Geest, Rob J.; Leeuwis, Jan Willem; Dendooven, Amélie; Pfister, Frederick; Bosch, Klazien; Hoeben, Kees A.; Vogels, Ilse M. C.; van der Giezen, Dionne M.; Dietrich, Nadine; Hammes, Hans-Peter; Goldschmeding, Roel; Klaassen, Ingeborg; van Noorden, Cornelis J. F.; Schlingemann, Reinier O.

2014-01-01

Early retinal vascular changes in the development of diabetic retinopathy (DR) include capillary basal lamina (BL) thickening, pericyte loss and the development of acellular capillaries. Expression of the CCN (connective tissue growth factor/cysteine-rich 61/nephroblastoma overexpressed) family

Neuropsychiatric symptoms in Vascular Cognitive Impairment: A systematic review

Directory of Open Access Journals (Sweden)

Chan Tiel

Full Text Available Neuropsychiatric symptoms or Behavioral and Psychological Symptoms of Dementia (BPSD are common and invariably appear at some point during the course of the disease, mediated both by cerebrovascular disease and neurodegenerative processes. Few studies have compared the profiles of BPSD in Vascular Cognitive Impairment (VCI of different subtypes (subcortical or cortical and clinical stages (Vascular Cognitive Impairment No Dementia [VaCIND] and Vascular Dementia [VaD].Objective:To review the BPSD associated with different subtypes and stages of VCI using the Neuropsychiatric Inventory (NPI.Methods:Medline, Scielo and Lilacs databases were searched for the period January 2000 to December 2014, with the key words: "BPSD AND Vascular Dementia, "NPI AND Vascular Dementia" and "NPI AND VCI. Qualitative analysis was performed on studies evaluating BPSD in VCI, using the Neuropsychiatric Inventory (NPI.Results:A total of 82 studies were retrieved of which 13 were eligible and thus included. Among the articles selected, 4 compared BPSD in Subcortical Vascular Dementia (SVaD versus Cortical-Subcortical Vascular Dementia (CSVaD, 3 involved comparisons between SVaD and VaCIND, 1 study analyzed differences between CSVaD and VaCIND, while 5 studies assessed BPSD in CSVaD. Subcortical and Cortical-Subcortical VaD were associated predominantly with Apathy and Depression. VaCIND may present fewer behavioral symptoms than VaD.Conclusion:The profile of BPSD differs for different stages of VCI. Determining the most prevalent BPSD in VCI subtypes might be helpful for improving early diagnosis and management of these symptoms.

The vascular surgery workforce: a survey of consultant vascular surgeons in the UK, 2014.

Science.gov (United States)

Harkin, D W; Beard, J D; Shearman, C P; Wyatt, M G

2015-04-01

The purpose of this study was to describe the demographics, training, and practice characteristics of consultant vascular surgeons across the UK to provide an assessment of current, and inform future prediction of workforce needs. A questionnaire was developed using a modified Delphi process to generate questionnaire items. The questionnaire was emailed to all consultant vascular surgeons (n = 450) in the UK who were members of the Vascular Society of Great Britain & Ireland. 352 consultant vascular surgeons from 95 hospital trusts across the UK completed the survey (78% response rate). The mean age was 50.6 years old, the majority (62%) were mid-career, but 24% were above the age of 55. Currently, 92% are men and only 8% women. 93% work full-time, with 60% working >50 hours, and 21% working >60 hours per week. The average team was 5 to 6 (range 2-10) vascular surgeons, with 23% working in a large team of ≥8. 17% still work in small teams of ≤3. Over 90% of consultant vascular surgeons perform the major index vascular surgery procedures (aneurysm repair, carotid endarterectomy, infra-inguinal bypass, amputation). While 84% perform standard endovascular abdominal aortic aneurysm repair (EVAR), <50% perform more complex endovascular aortic therapy. The majority of vascular surgeons "like their job" (85%) and are "satisfied" (69%) with their job. 34% of consultant vascular surgeons indicated they were "extremely likely" to retire within the next 10 years. This study provides the first detailed analysis of the new specialty of vascular surgery as practiced in the UK. There is a need to plan for a significant expansion in the consultant vascular surgeon workforce in the UK over the next 10 years to maintain the status quo. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Polyarteritis nodosa presenting as peripheral vascular disease and acute limb ischemia

Directory of Open Access Journals (Sweden)

A Shukla

2017-01-01

Full Text Available Acute limb ischemia and peripheral vascular disease (PVD are unusual presentations of polyarteritis nodosa (PAN. Here, we present a case with PVD of both lower limbs leading to foot claudication. Digital subtraction angiography showed narrowing, irregularity, and occlusion of both lower limb arteries with no involvement of the abdomen visceral arteries. Based on significant weight loss, diastolic blood pressure >90 mmHg, myalgia, testicular pain, and angiographic abnormalities in medium-sized arteries, he was diagnosed as having PAN. He was treated with corticosteroid and bolus intravenous cyclophosphamide following which he had prompt and near-complete recovery of the symptoms without any tissue loss.

A multifaceted approach to maximize erectile function and vascular health.

Science.gov (United States)

Meldrum, David R; Gambone, Joseph C; Morris, Marge A; Ignarro, Louis J

2010-12-01

To review the role of various factors influencing vascular nitric oxide (NO) and cyclic GMP, and consequently, erectile function and vascular health. Pertinent publications are reviewed. Daily moderate exercise stimulates vascular NO production. Maintenance of normal body weight and waist/hip ratio allows NO stimulation by insulin. Decreased intake of fat, sugar, and simple carbohydrates rapidly converted to sugar reduces the adverse effects of fatty acids and sugar on endothelial NO production. Omega-3 fatty acids stimulate endothelial NO release. Antioxidants boost NO production and prevent NO breakdown. Folic acid, calcium, vitamin C, and vitamin E support the biochemical pathways leading to NO release. Cessation of smoking and avoidance of excessive alcohol preserve normal endothelial function. Moderate use of alcohol and certain proprietary supplements may favorably influence erectile and vascular function. Treatment of any remaining testosterone deficit will both increase erectile function and reduce any associated metabolic syndrome. After production of NO and cyclic GMP are improved, use of phosphodiesterase-5 inhibitors should result in greater success in treating remaining erectile dysfunction. Recent studies have also suggested positive effects of phosphodiesterase-5 inhibitors on vascular function. A multifaceted approach will maximize both erectile function and vascular health. Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Automated tracking of the vascular tree on DSA images

International Nuclear Information System (INIS)

Alperin, N.; Hoffmann, K.R.; Doi, K.

1990-01-01

Determination of the vascular tree structure is important for reconstruction of three-dimensional vascular tree from biplane images, for assessment of the significance of a lesion, and for planning treatment for arteriovenous malformation. To automate these analyses, the authors of this paper are developing a method to determine the vascular tree structure from digital subtraction angiography (DSA) images. The authors have previously described a vessel tracking method, based on the double-square-box technique. To improve the tracking accuracy, they have developed and integrated with the previous method a connectivity test and guided-sector-search technique. The connectivity test, based on region growing techniques, eliminates tracking across nonvessel regions. The guided sector-search method incorporates information from a larger are of the image to guide the search for the next tracking point

Tofacitinib Ameliorates Murine Lupus and Its Associated Vascular Dysfunction.

Science.gov (United States)

Furumoto, Yasuko; Smith, Carolyne K; Blanco, Luz; Zhao, Wenpu; Brooks, Stephen R; Thacker, Seth G; Abdalrahman, Zarzour; Sciumè, Giuseppe; Tsai, Wanxia L; Trier, Anna M; Nunez, Leti; Mast, Laurel; Hoffmann, Victoria; Remaley, Alan T; O'Shea, John J; Kaplan, Mariana J; Gadina, Massimo

2017-01-01

Dysregulation of innate and adaptive immune responses contributes to the pathogenesis of systemic lupus erythematosus (SLE) and its associated premature vascular damage. No drug to date targets both systemic inflammatory disease and the cardiovascular complications of SLE. Tofacitinib is a JAK inhibitor that blocks signaling downstream of multiple cytokines implicated in lupus pathogenesis. While clinical trials have shown that tofacitinib exhibits significant clinical efficacy in various autoimmune diseases, its role in SLE and the associated vascular pathology remains to be characterized. MRL/lpr lupus-prone mice were administered tofacitinib or vehicle by gavage for 6 weeks (therapeutic arm) or 8 weeks (preventive arm). Nephritis, skin inflammation, serum levels of autoantibodies and cytokines, mononuclear cell phenotype and gene expression, neutrophil extracellular traps (NETs) release, endothelium-dependent vasorelaxation, and endothelial differentiation were compared in treated and untreated mice. Treatment with tofacitinib led to significant improvement in measures of disease activity, including nephritis, skin inflammation, and autoantibody production. In addition, tofacitinib treatment reduced serum levels of proinflammatory cytokines and interferon responses in splenocytes and kidney tissue. Tofacitinib also modulated the formation of NETs and significantly increased endothelium-dependent vasorelaxation and endothelial differentiation. The drug was effective in both preventive and therapeutic strategies. Tofacitinib modulates the innate and adaptive immune responses, ameliorates murine lupus, and improves vascular function. These results indicate that JAK inhibitors have the potential to be beneficial in SLE and its associated vascular damage. © 2016, American College of Rheumatology.

Features and selection of vascular access devices.

Science.gov (United States)

Sansivero, Gail Egan

2010-05-01

To review venous anatomy and physiology, discuss assessment parameters before vascular access device (VAD) placement, and review VAD options. Journal articles, personal experience. A number of VAD options are available in clinical practice. Access planning should include comprehensive assessment, with attention to patient participation in the planning and selection process. Careful consideration should be given to long-term access needs and preservation of access sites. Oncology nurses are uniquely suited to perform a key role in VAD planning and placement. With knowledge of infusion therapy, anatomy and physiology, device options, and community resources, nurses can be key leaders in preserving vascular access and improving the safety and comfort of infusion therapy. Copyright 2010 Elsevier Inc. All rights reserved.

The SK3 channel promotes placental vascularization by enhancing secretion of angiogenic factors.

Science.gov (United States)

Rada, Cara C; Murray, Grace; England, Sarah K

2014-11-15

Proper placental perfusion is essential for fetal exchange of oxygen, nutrients, and waste with the maternal circulation. Impairment of uteroplacental vascular function can lead to pregnancy complications, including preeclampsia and intrauterine growth restriction (IUGR). Potassium channels have been recognized as regulators of vascular proliferation, angiogenesis, and secretion of vasoactive factors, and their dysfunction may underlie pregnancy-related vascular diseases. Overexpression of one channel in particular, the small-conductance calcium-activated potassium channel 3 (SK3), is known to increase vascularization in mice, and mice overexpressing the SK3 channel (SK3(T/T) mice) have a high rate of fetal demise and IUGR. Here, we show that overexpression of SK3 causes fetal loss through abnormal placental vascularization. We previously reported that, at pregnancy day 14, placentas isolated from SK3(T/T) mice are smaller than those obtained from wild-type mice. In this study, histological analysis reveals that SK3(T/-) placentas at this stage have abnormal placental morphology, and microcomputed tomography shows that these placentas have significantly larger and more blood vessels than those from wild-type mice. To identify the mechanism by which these vascularization defects occur, we measured levels of vascular endothelial growth factor (VEGF), placental growth factor, and the soluble form of VEGF receptor 1 (sFlt-1), which must be tightly regulated to ensure proper placental development. Our data reveal that overexpression of SK3 alters systemic and placental ratios of the angiogenic factor VEGF to antiangiogenic factor sFlt-1 throughout pregnancy. Additionally, we observe increased expression of hypoxia-inducing factor 2α in SK3(T/-) placentas. We conclude that the SK3 channel modulates placental vascular development and fetal health by altering VEGF signaling. Copyright © 2014 the American Physiological Society.

Multimodality optical coherence tomography and fluorescence confocal scanning laser ophthalmoscopy in a zebrafish model of retinal vascular occlusion and remodeling

Science.gov (United States)

Li, Xiaoyue; Spitz, Kathleen; Bozic, Ivan; Tao, Yuankai K.

2018-02-01

Neovascularization in diabetic retinopathy (DR) and age-related macular degeneration (AMD) result in severe vision-loss and are two of the leading causes of blindness. The structural, metabolic, and vascular changes underlying retinal neovascularization are unknown and, thus, there is an unmet need to identify mechanisms of pathogenesis and novel anti-angiogenic therapies. Zebrafish is a robust ophthalmological model because its retina has comparable structure to the human retina and its fecundity and life-cycle enable development of mutant phenotypes of human pathologies. Here, we perform multimodal imaging with OCT and fluorescence confocal scanning laser ophthalmoscopy (cSLO) to identify changes in retinal structure and function in a zebrafish model of vascular leakage. Transgenic zebrafish with EGFP tagged plasma protein were imaged longitudinally at six time points over two weeks to visualize vascular perfusion changes from diethylaminobenzaldehyde (DEAB) treatment. Complementary contrast from OCT-A perfusion maps and cSLO imaging of plasma protein EGFP shows vascular occlusions posttreatment. cSLO images confirm presence of vessels despite loss of OCT-A signal. Plasma protein EGFP contrast also shows significant changes in vessel structure as compared to baseline images. OCT structural volumes show empty vessel cross-sections confirming non-perfusion. In addition, we present algorithms for automated biometric identification of OCT datasets using OCT-A vascular patterns in the presence of significant vascular perfusion changes. These results establish a framework for large-scale in vivo assays to identify novel anti-angiogenic compounds and understand the mechanisms ofneovascularization associated with retinal ocular pathologies.

Relational databases for rare disease study: application to vascular anomalies.

Science.gov (United States)

Perkins, Jonathan A; Coltrera, Marc D

2008-01-01

To design a relational database integrating clinical and basic science data needed for multidisciplinary treatment and research in the field of vascular anomalies. Based on data points agreed on by the American Society of Pediatric Otolaryngology (ASPO) Vascular Anomalies Task Force. The database design enables sharing of data subsets in a Health Insurance Portability and Accountability Act (HIPAA)-compliant manner for multisite collaborative trials. Vascular anomalies pose diagnostic and therapeutic challenges. Our understanding of these lesions and treatment improvement is limited by nonstandard terminology, severity assessment, and measures of treatment efficacy. The rarity of these lesions places a premium on coordinated studies among multiple participant sites. The relational database design is conceptually centered on subjects having 1 or more lesions. Each anomaly can be tracked individually along with their treatment outcomes. This design allows for differentiation between treatment responses and untreated lesions' natural course. The relational database design eliminates data entry redundancy and results in extremely flexible search and data export functionality. Vascular anomaly programs in the United States. A relational database correlating clinical findings and photographic, radiologic, histologic, and treatment data for vascular anomalies was created for stand-alone and multiuser networked systems. Proof of concept for independent site data gathering and HIPAA-compliant sharing of data subsets was demonstrated. The collaborative effort by the ASPO Vascular Anomalies Task Force to create the database helped define a common vascular anomaly data set. The resulting relational database software is a powerful tool to further the study of vascular anomalies and the development of evidence-based treatment innovation.

Vascular responses to radiotherapy and androgen-deprivation therapy in experimental prostate cancer

International Nuclear Information System (INIS)

Røe, Kathrine; Mikalsen, Lars TG; Kogel, Albert J van der; Bussink, Johan; Lyng, Heidi; Ree, Anne H; Marignol, Laure; Olsen, Dag R

2012-01-01

Radiotherapy (RT) and androgen-deprivation therapy (ADT) are standard treatments for advanced prostate cancer (PC). Tumor vascularization is recognized as an important physiological feature likely to impact on both RT and ADT response, and this study therefore aimed to characterize the vascular responses to RT and ADT in experimental PC. Using mice implanted with CWR22 PC xenografts, vascular responses to RT and ADT by castration were visualized in vivo by DCE MRI, before contrast-enhancement curves were analyzed both semi-quantitatively and by pharmacokinetic modeling. Extracted image parameters were correlated to the results from ex vivo quantitative fluorescent immunohistochemical analysis (qIHC) of tumor vascularization (9 F1), perfusion (Hoechst 33342), and hypoxia (pimonidazole), performed on tissue sections made from tumors excised directly after DCE MRI. Compared to untreated (Ctrl) tumors, an improved and highly functional vascularization was detected in androgen-deprived (AD) tumors, reflected by increases in DCE MRI parameters and by increased number of vessels (VN), vessel density (VD), and vessel area fraction (VF) from qIHC. Although total hypoxic fractions (HF) did not change, estimated acute hypoxia scores (AHS) – the proportion of hypoxia staining within 50 μm from perfusion staining – were increased in AD tumors compared to in Ctrl tumors. Five to six months after ADT renewed castration-resistant (CR) tumor growth appeared with an even further enhanced tumor vascularization. Compared to the large vascular changes induced by ADT, RT induced minor vascular changes. Correlating DCE MRI and qIHC parameters unveiled the semi-quantitative parameters area under curve (AUC) from initial time-points to strongly correlate with VD and VF, whereas estimation of vessel size (VS) by DCE MRI required pharmacokinetic modeling. HF was not correlated to any DCE MRI parameter, however, AHS may be estimated after pharmacokinetic modeling. Interestingly, such

Mitochondrial Cyclophilin D in Vascular Oxidative Stress and Hypertension.

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Itani, Hana A; Dikalova, Anna E; McMaster, William G; Nazarewicz, Rafal R; Bikineyeva, Alfiya T; Harrison, David G; Dikalov, Sergey I

2016-06-01

Vascular superoxide (O˙2 (-)) and inflammation contribute to hypertension. The mitochondria are an important source of O˙2 (-); however, the regulation of mitochondrial O˙2 (-) and the antihypertensive potential of targeting the mitochondria remain poorly defined. Angiotensin II and inflammatory cytokines, such as interleukin 17A and tumor necrosis factor-α (TNFα) significantly contribute to hypertension. We hypothesized that angiotensin II and cytokines co-operatively induce cyclophilin D (CypD)-dependent mitochondrial O˙2 (-) production in hypertension. We tested whether CypD inhibition attenuates endothelial oxidative stress and reduces hypertension. CypD depletion in CypD(-/-) mice prevents overproduction of mitochondrial O˙2 (-) in angiotensin II-infused mice, attenuates hypertension by 20 mm Hg, and improves vascular relaxation compared with wild-type C57Bl/6J mice. Treatment of hypertensive mice with the specific CypD inhibitor Sanglifehrin A reduces blood pressure by 28 mm Hg, inhibits production of mitochondrial O˙2 (-) by 40%, and improves vascular relaxation. Angiotensin II-induced hypertension was associated with CypD redox activation by S-glutathionylation, and expression of the mitochondria-targeted H2O2 scavenger, catalase, abolished CypD S-glutathionylation, prevented stimulation mitochondrial O˙2 (-), and attenuated hypertension. The functional role of cytokine-angiotensin II interplay was confirmed by co-operative stimulation of mitochondrial O˙2 (-) by 3-fold in cultured endothelial cells and impairment of aortic relaxation incubated with combination of angiotensin II, interleukin 17A, and tumor necrosis factor-α which was prevented by CypD depletion or expression of mitochondria-targeted SOD2 and catalase. These data support a novel role of CypD in hypertension and demonstrate that targeting CypD decreases mitochondrial O˙2 (-), improves vascular relaxation, and reduces hypertension. © 2016 American Heart Association, Inc.

Enhanced growth and improved vascular function in offspring from successive pregnancies in endothelial nitric oxide synthase knockout mice

NARCIS (Netherlands)

Longo, M; Jain, [No Value; Langenveld, J; Vedernikov, YP; Garfield, RE; Hankins, GDV; Anderson, GD; Saade, GR

2004-01-01

Objective: Transgenic mice that lack endothelial nitric oxide synthase have offspring with growth deficiency and abnormal vascular reactivity in later life. Our objective was to evaluate the role of parity in the modulation of the fetal programming of growth and vascular responses in these

Interventions to improve long-term weight loss in patients following bariatric surgery: challenges and solutions

Directory of Open Access Journals (Sweden)

McGrice M

2015-06-01

Full Text Available Melanie McGrice, Kathlene Don Paul Nutrition Plus Enterprises, Melbourne, VIC, Australia Abstract: Bariatric surgery aims to provide long-term weight loss and improvement in weight-related comorbidities. Unfortunately, some patients do not achieve predicted weight loss targets and many regain a portion of their lost weight within 2–10 years postsurgery. A review of the literature found that behavioral, dietary, psychological, physical, and medical considerations can all play a role in suboptimal long-term weight loss. Recommendations to optimize long-term weight loss include ensuring that the patient understands how the procedure works, preoperative and postoperative education sessions, tailored nutritional supplements, restraint with liquid kilojoules, pureed foods, grazing and eating out of the home, an average of 60 minutes of physical activity per day, and lifelong annual medical, psychological, and dietary assessments.Keywords: weight, bariatric, surgery

Usefulness of semiquantitative analysis of dipyridamole-thallium-201 redistribution for improving risk stratification before vascular surgery

International Nuclear Information System (INIS)

Levinson, J.R.; Boucher, C.A.; Coley, C.M.; Guiney, T.E.; Strauss, H.W.; Eagle, K.A.

1990-01-01

Preoperative dipyridamole-thallium-201 scanning is sensitive in identifying patients prone to ischemic cardiac complications after vascular surgery, but most patients with redistribution do not have an event after surgery. Therefore, its positive predictive value is limited. To determine which patients with thallium redistribution are at highest risk, dipyridamole-thallium-201 images were interpreted semiquantitatively. Sixty-two consecutive patients with redistribution on preoperative dipyridamole-thallium-201 planar imaging studies were identified. Each thallium scan was then analyzed independently by 2 observers for the number of myocardial segments out of 15, the number of thallium views out of 3 and the number of coronary artery territories with redistribution. Seventeen patients (27%) had postoperative ischemic events, including unstable angina pectoris, ischemic pulmonary edema, myocardial infarction and cardiac death. Thallium predictors of ischemic operative complications included thallium redistribution greater than or equal to 4 myocardial segments (p = 0.03), greater than or equal to 2 of the 3 planar views (p = 0.005) and greater than or equal to 2 coronary territories (p = 0.007). No patient with redistribution in only 1 view had an ischemic event (0 of 15). Thus, determining the extent of redistribution by dipyridamole-thallium-201 scanning improves risk stratification before vascular surgery. Patients with greater numbers of myocardial segments and greater numbers of coronary territories showing thallium-201 redistribution are at higher risk for ischemic cardiac complications. In contrast, when the extent of thallium redistribution is limited, there is a lower risk despite the presence of redistribution

VEGF-A, cytoskeletal dynamics, and the pathological vascular phenotype

International Nuclear Information System (INIS)

Nagy, Janice A.; Senger, Donald R.

2006-01-01

Normal angiogenesis is a complex process involving the organization of proliferating and migrating endothelial cells (ECs) into a well-ordered and highly functional vascular network. In contrast, pathological angiogenesis, which is a conspicuous feature of tumor growth, ischemic diseases, and chronic inflammation, is characterized by vessels with aberrant angioarchitecture and compromised barrier function. Herein we review the subject of pathological angiogenesis, particularly that driven by vascular endothelial growth factor (VEGF-A), from a new perspective. We propose that the serious structural and functional anomalies associated with VEGF-A-elicited neovessels, reflect, at least in part, imbalances in the internal molecular cues that govern the ordered assembly of ECs into three dimensional vascular networks and preserve vessel barrier function. Adopting such a viewpoint widens the focus from solely on specific pro-angiogenic stimuli such as VEGF-A to include a key set of cytoskeletal regulatory molecules, the Rho GTPases, which are known to direct multiple aspects of vascular morphogenesis including EC motility, alignment, multi-cellular organization, as well as intercellular junction integrity. We offer this perspective to draw attention to the importance of endothelial cytoskeletal dynamics for proper neovascularization and to suggest new therapeutic strategies with the potential to improve the pathological vascular phenotype

Vascular pattern formation in plants.

Science.gov (United States)

Scarpella, Enrico; Helariutta, Ykä

2010-01-01

Reticulate tissue systems exist in most multicellular organisms, and the principles underlying the formation of cellular networks have fascinated philosophers, mathematicians, and biologists for centuries. In particular, the beautiful and varied arrangements of vascular tissues in plants have intrigued mankind since antiquity, yet the organizing signals have remained elusive. Plant vascular tissues form systems of interconnected cell files throughout the plant body. Vascular cells are aligned with one another along continuous lines, and vascular tissues differentiate at reproducible positions within organ environments. However, neither the precise path of vascular differentiation nor the exact geometry of vascular networks is fixed or immutable. Several recent advances converge to reconcile the seemingly conflicting predictability and plasticity of vascular tissue patterns. A control mechanism in which an apical-basal flow of signal establishes a basic coordinate system for body axis formation and vascular strand differentiation, and in which a superimposed level of radial organizing cues elaborates cell patterns, would generate a reproducible tissue configuration in the context of an underlying robust, self-organizing structure, and account for the simultaneous regularity and flexibility of vascular tissue patterns. Copyright 2010 Elsevier Inc. All rights reserved.

Influence of L-citrulline and watermelon supplementation on vascular function and exercise performance.

Science.gov (United States)

Figueroa, Arturo; Wong, Alexei; Jaime, Salvador J; Gonzales, Joaquin U

2017-01-01

L-Citrulline, either synthetic or in watermelon, may improve vascular function through increased L-arginine bioavailability and nitric oxide synthesis. This article analyses potential vascular benefits of L-citrulline and watermelon supplementation at rest and during exercise. There is clear evidence that acute L-citrulline ingestion increases plasma L-arginine, the substrate for endothelial nitric oxide synthesis. However, the subsequent acute improvement in nitric oxide production and mediated vasodilation is inconsistent, which likely explains the inability of acute L-citrulline or watermelon to improve exercise tolerance. Recent studies have shown that chronic L-citrulline supplementation increases nitric oxide synthesis, decreases blood pressure, and may increase peripheral blood flow. These changes are paralleled by improvements in skeletal muscle oxygenation and performance during endurance exercise. The antihypertensive effect of L-citrulline/watermelon supplementation is evident in adults with prehypertension or hypertension, but not in normotensives. However, L-citrulline supplementation may attenuate the blood pressure response to exercise in normotensive men. The beneficial vascular effects of L-citrulline/watermelon supplementation may stem from improvements in the L-arginine/nitric oxide pathway. Reductions in resting blood pressure with L-citrulline/watermelon supplementation may have major implications for individuals with prehypertension and hypertension. L-Citrulline supplementation, but not acute ingestion, have shown to improve exercise performance in young healthy adults.

[Multicentric hyaline vascular Castleman's disease. A POEMS type variant].

Science.gov (United States)

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.

Disruptive technological advances in vascular access for dialysis: an overview.

Science.gov (United States)

Yeo, Wee-Song; Ng, Qin Xiang

2017-11-29

End-stage kidney disease (ESKD), one of the most prevalent diseases in the world and with increasing incidence, is associated with significant morbidity and mortality. Current available modes of renal replacement therapy (RRT) include dialysis and renal transplantation. Though renal transplantation is the preferred and ideal mode of RRT, this modality may not be available to all patients with ESKD. Moreover, renal transplant recipients are constantly at risk of complications associated with immunosuppression and immunosuppressant use, and posttransplant lymphoproliferative disorder. Dialysis may be the only available modality in certain patients. However, dialysis has its limitations, which include issues associated with lack of vascular access, risks of infections and vascular thrombosis, decreased quality of life, and absence of biosynthetic functions of the kidney. In particular, the creation and maintenance of hemodialysis vascular access in children poses a unique set of challenges to the pediatric nephrologist owing to the smaller vessel diameters and vascular hyperreactivity compared with adult patients. Vascular access issues continue to be one of the major limiting factors prohibiting the delivery of adequate dialysis in ESKD patients and is the Achilles' heel of hemodialysis. This review aims to provide a critical overview of disruptive technological advances and innovations for vascular access. Novel strategies in preventing neointimal hyperplasia, novel bioengineered products, grafts and devices for vascular access will be discussed. The potential impact of these solutions on improving the morbidity encountered by dialysis patients will also be examined.

Memory Loss: 7 Tips to Improve Your Memory

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... re not alone. Everyone forgets things occasionally. Still, memory loss is nothing to take lightly. Although there are no guarantees when it comes to preventing memory loss or dementia, certain activities might help. Consider ...

[Application of 1% lauromacrogol in the treatment of facial refractory hemangioma and vascular malformations].

Science.gov (United States)

Wang, Yin; Zhu, Fei; Ning, Jin-long; Li, Xiao-jing; Liu, Ye

2012-11-01

To investigate the clinical effect of 1% lauromacrogol for the treatment of facial refractory hemangioma and vascular malformation. From Sept 2009 to Nov 2011, 55 patients (20 male, 35 female, 1 month to 30 years) with different types of facial hemangiorwa and vascular malformation about 1.0 cm x (0. 5-5.0) cm x 10.0 cm in size, underwent 1% lauromacrogol intratumor injection therapy. Generally, the injection dose, concentration, frequency were determined by the age of the patients, the volume and depth of the lesion. The dose was limited to 10 mg every time. The injection interval is 14 weeks. After followed up for 3-16 months, 41 cases were cured, 9 cases were greatly improved, and 5 were partially improved. Skin necrosis happened in only 2 cases. Lauromacrogol is safe, simple and effective as a sderosing agent for the treatment of facial refractory hemangioma and vascular malformation. It provides a new and alternative way for the treatment of facial refractory hemangioma and vascular malformation.

Reconstruction of lower end of radius using vascularized upper end of fibula

Directory of Open Access Journals (Sweden)

Koul Ashok

2007-01-01

Full Text Available Background: Giant cell tumor is a fairly common locally invasive tumor in young adults. The lower end of the radius is the second commonest site for this tumor. The most common treatment for this tumor is curettage with or without bone grafting but it carries a significant rate of recurrence. Excision is the treatment of choice, especially for cases in which the cortex has been breached. After excision of the distal end of the radius, different procedures have been described to reconstruct the defect of distal radius. These include partial arthrodesis and hemiarthroplasty using the upper end of the fibula. The upper end of the fibula has a morphological resemblance to the lower end of the radius and has been used to replace the latter. Traditionally it was used as a ′free′ (non-vascularized graft. More recently the upper end of the fibula has been transferred as a vascularized transfer for the same purpose. Though vascularized transfer should be expected to be more physiological, its superiority over the technically simpler non-vascularized transfer has not been conclusively proven. Materials and Methods: Two patients are presented who had giant cell tumor of distal radius. They underwent wide local excision and reconstruction with free vascularized upper end of the fibula. Result: Follow-up period was two and a half years and 12 months respectively. Both patients have returned to routine work. One patient has excellent functional result and the other has a good result. Conclusion: Vascularized upper end of fibula transfer is a reliable method of reconstruction for loss of the distal end of the radius that restores local anatomy and physiology.

Vascular grading of angiogenesis

DEFF Research Database (Denmark)

Hansen, S; Grabau, D A; Sørensen, Flemming Brandt

2000-01-01

The study aimed to evaluate the prognostic value of angiogenesis by vascular grading of primary breast tumours, and to evaluate the prognostic impact of adding the vascular grade to the Nottingham Prognostic Index (NPI). The investigation included 836 patients. The median follow-up time was 11...... years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. Angiogenesis was graded semiquantitatively by subjective scoring into three groups according to the expected number of microvessels in the most vascular tumour area. The vascular grading between observers...... for 24% of the patients, who had a shift in prognostic group, as compared to NPI, and implied a better prognostic dissemination. We concluded that the angiogenesis determined by vascular grading has independent prognostic value of clinical relevance for patients with breast cancer....

Vascular grading of angiogenesis

DEFF Research Database (Denmark)

Hansen, S; Grabau, D A; Sørensen, Flemming Brandt

2000-01-01

The study aimed to evaluate the prognostic value of angiogenesis by vascular grading of primary breast tumours, and to evaluate the prognostic impact of adding the vascular grade to the Nottingham Prognostic Index (NPI). The investigation included 836 patients. The median follow-up time was 11...... years and 4 months. The microvessels were immunohistochemically stained by antibodies against CD34. Angiogenesis was graded semiquantitatively by subjective scoring into three groups according to the expected number of microvessels in the most vascular tumour area. The vascular grading between observers...... impact for 24% of the patients, who had a shift in prognostic group, as compared to NPI, and implied a better prognostic dissemination. We concluded that the angiogenesis determined by vascular grading has independent prognostic value of clinical relevance for patients with breast cancer....

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

Science.gov (United States)

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.

Instrumentalization of eating improves weight loss maintenance in obesity

DEFF Research Database (Denmark)

Christensen, Bodil Just; Iepsen, Eva Pers Winning; Lundgren, Julie Rehné

2017-01-01

Aim: The purpose of this study was to identify psychosocial determinants for maintaining weight loss. Methods: 42 obese individuals who achieved a 12% weight loss before entering a 52-week weight maintenance program were interviewed qualitatively. Psychosocial factors related to weight loss...... weight loss maintenance was associated with an interplay between behavioral, affective and contextual changes. ‘Instrumentalization of eating behavior' seems to be an important element in long-term weight maintenance....

Clinical applications of robotic technology in vascular and endovascular surgery.

Science.gov (United States)

Antoniou, George A; Riga, Celia V; Mayer, Erik K; Cheshire, Nicholas J W; Bicknell, Colin D

2011-02-01

Emerging robotic technologies are increasingly being used by surgical disciplines to facilitate and improve performance of minimally invasive surgery. Robot-assisted intervention has recently been introduced into the field of vascular surgery to potentially enhance laparoscopic vascular and endovascular capabilities. The objective of this study was to review the current status of clinical robotic applications in vascular surgery. A systematic literature search was performed in order to identify all published clinical studies related to robotic implementation in vascular intervention. Web-based search engines were searched using the keywords "surgical robotics," "robotic surgery," "robotics," "computer assisted surgery," and "vascular surgery" or "endovascular" for articles published between January 1990 and November 2009. An evaluation and critical overview of these studies is reported. In addition, an analysis and discussion of supporting evidence for robotic computer-enhanced telemanipulation systems in relation to their applications in laparoscopic vascular and endovascular surgery was undertaken. Seventeen articles reporting on clinical applications of robotics in laparoscopic vascular and endovascular surgery were detected. They were either case reports or retrospective patient series and prospective studies reporting laparoscopic vascular and endovascular treatments for patients using robotic technology. Minimal comparative clinical evidence to evaluate the advantages of robot-assisted vascular procedures was identified. Robot-assisted laparoscopic aortic procedures have been reported by several studies with satisfactory results. Furthermore, the use of robotic technology as a sole modality for abdominal aortic aneurysm repair and expansion of its applications to splenic and renal artery aneurysm reconstruction have been described. Robotically steerable endovascular catheter systems have potential advantages over conventional catheterization systems

Natural antioxidant ice cream acutely reduces oxidative stress and improves vascular function and physical performance in healthy individuals.

Science.gov (United States)

Sanguigni, Valerio; Manco, Melania; Sorge, Roberto; Gnessi, Lucio; Francomano, Davide

2017-01-01

The formation of reactive oxygen species (ROS) contributes to the pathogenesis and progression of several diseases. Polyphenols have been shown to be beneficial against ROS. The aim of this study was to evaluate the effects of a natural antioxidant ice cream on oxidative stress, vascular function, and physical performance. In this controlled, single-blind, crossover study, 14 healthy individuals were randomized to consume 100 g of either antioxidant ice cream containing dark cocoa powder and hazelnut and green tea extracts or milk chocolate ice cream (control ice cream). Participants were studied at baseline and 2 h after ingesting ice cream. Serum polyphenols, antioxidant status (ferric-reducing ability of plasma [FRAP]), nitric oxide (NOx) bioavailability, markers of oxidative stress (determination of reactive oxygen metabolites [d-ROMs] and hydrogen peroxide [H 2 O 2 ]), endothelium function (flow-mediated dilation [FMD] and reactive hyperemia index [RHI]), and exercise tolerance (stress test) were assessed, and the double product was measured. Serum polyphenols (P ice cream ingestion. No changes were found after control ice cream ingestion. To our knowledge, this is the first study to demonstrate that a natural ice cream rich in polyphenols acutely improved vascular function and physical performance in healthy individuals through a reduction in oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

In vitro model of vascularized bone: synergizing vascular development and osteogenesis.

Directory of Open Access Journals (Sweden)

Cristina Correia

Full Text Available Tissue engineering provides unique opportunities for regenerating diseased or damaged tissues using cells obtained from tissue biopsies. Tissue engineered grafts can also be used as high fidelity models to probe cellular and molecular interactions underlying developmental processes. In this study, we co-cultured human umbilical vein endothelial cells (HUVECs and human mesenchymal stem cells (MSCs under various environmental conditions to elicit synergistic interactions leading to the colocalized development of capillary-like and bone-like tissues. Cells were encapsulated at the 1:1 ratio in fibrin gel to screen compositions of endothelial growth medium (EGM and osteogenic medium (OM. It was determined that, to form both tissues, co-cultures should first be supplied with EGM followed by a 1:1 cocktail of the two media types containing bone morphogenetic protein-2. Subsequent studies of HUVECs and MSCs cultured in decellularized, trabecular bone scaffolds for 6 weeks assessed the effects on tissue construct of both temporal variations in growth-factor availability and addition of fresh cells. The resulting grafts were implanted subcutaneously into nude mice to determine the phenotype stability and functionality of engineered vessels. Two important findings resulted from these studies: (i vascular development needs to be induced prior to osteogenesis, and (ii the addition of additional hMSCs at the osteogenic induction stage improves both tissue outcomes, as shown by increased bone volume fraction, osteoid deposition, close proximity of bone proteins to vascular networks, and anastomosis of vascular networks with the host vasculature. Interestingly, these observations compare well with what has been described for native development. We propose that our cultivation system can mimic various aspects of endothelial cell-osteogenic precursor interactions in vivo, and could find utility as a model for studies of heterotypic cellular interactions that

Implementing tactical plans to improve water-energy loss management

OpenAIRE

Loureiro, D.; Alegre, H.; Silva, M. S.; Ribeiro, R.; Mamade, A.; Poças, A.

2015-01-01

Water utilities are aware of the water-energy loss relevance in supply systems. However, they still mainly focus on daily water loss control (real and apparent losses), without considering the impact on embedded energy. Moreover, they are mostly concerned with the economic dimension and, in most cases, tend to disregard the impact that water-energy loss may have on the quality of service, communication with the customers, social awareness, water quality and environment. This paper focuses on ...

Vascular and micro-environmental influences on MSC-coral hydroxyapatite construct-based bone tissue engineering.

Science.gov (United States)

Cai, Lei; Wang, Qian; Gu, Congmin; Wu, Jingguo; Wang, Jian; Kang, Ning; Hu, Jiewei; Xie, Fang; Yan, Li; Liu, Xia; Cao, Yilin; Xiao, Ran

2011-11-01

Bone tissue engineering (BTE) has been demonstrated an effective approach to generate bone tissue and repair bone defect in ectopic and orthotopic sites. The strategy of using a prevascularized tissue-engineered bone grafts (TEBG) fabricated ectopically to repair bone defects, which is called live bone graft surgery, has not been reported. And the quantitative advantages of vascularization and osteogenic environment in promoting engineered bone formation have not been defined yet. In the current study we generated a tissue engineered bone flap with a vascular pedicle of saphenous arteriovenous in which an organized vascular network was observed after 4 weeks implantation, and followed by a successful repaire of fibular defect in beagle dogs. Besides, after a 9 months long term observation of engineered bone formation in ectopic and orthotopic sites, four CHA (coral hydroxyapatite) scaffold groups were evaluated by CT (computed tomography) analysis. By the comparison of bone formation and scaffold degradation between different groups, the influences of vascularization and micro-environment on tissue engineered bone were quantitatively analyzed. The results showed that in the first 3 months vascularization improved engineered bone formation by 2 times of non-vascular group and bone defect micro-environment improved it by 3 times of ectopic group, and the CHA-scaffold degradation was accelerated as well. Copyright © 2011 Elsevier Ltd. All rights reserved.

Sudden visual loss after cardiac resynchronization therapy device implantation.

Science.gov (United States)

De Vitis, Luigi A; Marchese, Alessandro; Giuffrè, Chiara; Carnevali, Adriano; Querques, Lea; Tomasso, Livia; Baldin, Giovanni; Maestranzi, Gisella; Lattanzio, Rosangela; Querques, Giuseppe; Bandello, Francesco

2017-03-10

To report a case of sudden decrease in visual acuity possibly due to a cardiogenic embolism in a patient who underwent cardiac resynchronization therapy (CRT) device implantation. A 62-year-old man with severe left ventricular systolic dysfunction and a left bundle branch block was referred to our department because of a sudden decrease in visual acuity. Nine days earlier, he had undergone cardiac transapical implantation of a CRT device, which was followed, 2 days later, by an inflammatory reaction. The patient underwent several general and ophthalmologic examinations, including multimodal imaging. At presentation, right eye (RE) best-corrected visual acuity (BCVA) was counting fingers and RE pupil was hyporeactive. Fundus examination revealed white-centered hemorrhagic dots suggestive of Roth spots. Fluorescein angiography showed delay in vascular perfusion during early stage, late hyperfluorescence of the macula and optic disk, and peripheral perivascular leakage. The first visual field test showed complete loss of vision RE and a normal left eye. Due to suspected giant cell arteritis, temporal artery biopsy was performed. Thirty minutes after the procedure, an ischemic stroke with right hemisyndrome and aphasia occurred. The RE BCVA worsened to hands motion. Four months later, RE BCVA did not improve, despite improvement in fluorescein angiography inflammatory sign. We report a possible cardiogenic embolism secondary to undiagnosed infective endocarditis causing monocular visual loss after CRT device implantation. It remains unclear how the embolus caused severe functional damage without altering the retinal anatomical structure.

Switching to multiple daily injection therapy with glulisine improves glycaemic control, vascular damage and treatment satisfaction in basal insulin glargine-injected diabetic patients.

Science.gov (United States)

Yanagisawa, Katsuyuki; Ashihara, Junya; Obara, Shinji; Wada, Norio; Takeuchi, Masayoshi; Nishino, Yuri; Maeda, Sayaka; Ishibashi, Yuji; Yamagishi, Sho-ichi

2014-11-01

Basal and bolus insulin therapy is required for strict blood control in diabetic patients, which could lead to prevention of vascular complications in diabetes. However, the optimal combination regimen is not well established. Fifty-nine diabetic patients (49 type 1 and 10 type 2; 52.9 ± 13.3 years old) whose blood glucose levels were uncontrolled (HbA1c  > 6.2%) by combination treatment of basal insulin glargine with multiple daily pre-meal injections of bolus short-acting insulin [aspart (n = 19), lispro (n = 37) and regular human insulin (n = 3)] for at least 8 weeks were enrolled in this study. We examined whether glycaemic control and vascular injury were improved by replacement of short-acting insulin with glulisine. Patient satisfaction was assessed with Diabetes Treatment Satisfaction Questionnaire. Although bolus and basal insulin doses were almost unchanged before and after replacement therapy, switching to glulisine insulin for 24 weeks significantly decreased level of HbA1c , advanced glycation end products (AGEs), soluble receptor for AGEs (sRAGE), monocyte chemoattractant protein-1 (MCP-1) and urinary albumin excretion. In multiple stepwise regression analysis, change in MCP-1 values from baseline (ΔMCP-1) was a sole determinant of log urinary albumin excretion. ΔAGEs and ΔsRAGE were independently correlated with each other. The relationship between ΔMCP-1 and ΔsRAGE was marginally significant (p = 0.05). Replacement of short-acting insulin by glulisine significantly increased Diabetes Treatment Satisfaction Questionnaire scores. Our present study suggests that combination therapy of glargine with multiple daily pre-meal injections of glulisine might show superior efficacy in controlling blood glucose, preventing vascular damage and improving treatment satisfaction in diabetic patients. Copyright © 2014 John Wiley & Sons, Ltd.

Double-filter identification of vascular-expressed genes using Arabidopsis plants with vascular hypertrophy and hypotrophy.

Science.gov (United States)

Ckurshumova, Wenzislava; Scarpella, Enrico; Goldstein, Rochelle S; Berleth, Thomas

2011-08-01

Genes expressed in vascular tissues have been identified by several strategies, usually with a focus on mature vascular cells. In this study, we explored the possibility of using two opposite types of altered tissue compositions in combination with a double-filter selection to identify genes with a high probability of vascular expression in early organ primordia. Specifically, we generated full-transcriptome microarray profiles of plants with (a) genetically strongly reduced and (b) pharmacologically vastly increased vascular tissues and identified a reproducible cohort of 158 transcripts that fulfilled the dual requirement of being underrepresented in (a) and overrepresented in (b). In order to assess the predictive value of our identification scheme for vascular gene expression, we determined the expression patterns of genes in two unbiased subsamples. First, we assessed the expression patterns of all twenty annotated transcription factor genes from the cohort of 158 genes and found that seventeen of the twenty genes were preferentially expressed in leaf vascular cells. Remarkably, fifteen of these seventeen vascular genes were clearly expressed already very early in leaf vein development. Twelve genes with published leaf expression patterns served as a second subsample to monitor the representation of vascular genes in our cohort. Of those twelve genes, eleven were preferentially expressed in leaf vascular tissues. Based on these results we propose that our compendium of 158 genes represents a sample that is highly enriched for genes expressed in vascular tissues and that our approach is particularly suited to detect genes expressed in vascular cell lineages at early stages of their inception. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Vascular defects and sensorineural deafness in a mouse model of Norrie disease.

Science.gov (United States)

Rehm, Heidi L; Zhang, Duan-Sun; Brown, M Christian; Burgess, Barbara; Halpin, Chris; Berger, Wolfgang; Morton, Cynthia C; Corey, David P; Chen, Zheng-Yi

2002-06-01

Norrie disease is an X-linked recessive syndrome of blindness, deafness, and mental retardation. A knock-out mouse model with an Ndp gene disruption was studied. We examined the hearing phenotype, including audiological, histological, and vascular evaluations. As is seen in humans, the mice had progressive hearing loss leading to profound deafness. The primary lesion was localized to the stria vascularis, which houses the main vasculature of the cochlea. Fluorescent dyes showed an abnormal vasculature in this region and eventual loss of two-thirds of the vessels. We propose that one of the principal functions of norrin in the ear is to regulate the interaction of the cochlea with its vasculature.

Contrast-enhanced Harmonic power Doppler ultrasonography: Improved depiction of vascularity and characterization of flow pattern in hepatocellular carcinoma

International Nuclear Information System (INIS)

Baek, Hyung Chul; Yoon, Kwon Ha; Kim, Chang Guhn; Park, Ki Han; Won, Jong Jin

2000-01-01

To evaluate the value of contrast-enhanced harmonic power Doppler ultrasonography (PDUS) in depiction and characterization of tumoral vascularity in hepatocellular carcinoma (HCC). Thirty-three patients with HCC were prospectively evaluated with harmonic PDUS before and after injection of the contrast agent SH U 508A (2.5g, 300 mg/ml ). Unenhanced and serial dynamic scans at 15, 30, 45, 60, 90, 120, 150, 180, 240, 300 seconds after injection of contrast agents were obtained using a tissue harmonic technique with power Doppler imaging. The tumoral vascularity was expressed as percentage of power Doppler area, which was measured quantitatively by a computerized program (Ultrasonic Imaging Tool; Soongsil University, Seoul, Korea). The grade (0, no signal; 1, less than 5%; 2, 5-25%; 3, more than 25%) and flow pattern (intratumoral, detour, basket, and mixed) of tumoral vascularity were analyzed. Peak time of contrast-enhancement was measured on each tumor. After injection of contrast agent, tumoral flow signals increased in all lesions (100%). At unenhanced harmonic PDUS, flow signals were detected in 17 HCCs (52%); 15 tumors (46%) demonstrated grade 1 vascularity; and two (6%), grade 2. At contrast-enhanced harmonic PDUS, all tumors were detected vascularity; five (15%) were grade 1; eight (24%), grade 2; and 20 (61%), grade 3. Flow patterns were demonstated as follows at unenhanced harmonic PDUS; intratumoral pattern in 13 tumors (76%), detour in 2 (12%), and basket in 2 (12%). After injection of contrast agent, intratumoral pattern in 7 tumors (21%), detour 0 (0%), basket in 3 (9%) and mixed in 23 (70%) were demonstrated. Peak time of enhancement after injection of contrast agent was 30- 90 seconds in majority of the patients. Contrast-enhanced harmonic PDUS would be valuable in depiction of vascularity and characterization of flow pattern in HCC.

Contrast-enhanced Harmonic power Doppler ultrasonography: Improved depiction of vascularity and characterization of flow pattern in hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Baek, Hyung Chul; Yoon, Kwon Ha; Kim, Chang Guhn; Park, Ki Han; Won, Jong Jin [Wonkwang University School of Medicine, Iksa (Korea, Republic of)

2000-12-15

To evaluate the value of contrast-enhanced harmonic power Doppler ultrasonography (PDUS) in depiction and characterization of tumoral vascularity in hepatocellular carcinoma (HCC). Thirty-three patients with HCC were prospectively evaluated with harmonic PDUS before and after injection of the contrast agent SH U 508A (2.5g, 300 mg/ml ). Unenhanced and serial dynamic scans at 15, 30, 45, 60, 90, 120, 150, 180, 240, 300 seconds after injection of contrast agents were obtained using a tissue harmonic technique with power Doppler imaging. The tumoral vascularity was expressed as percentage of power Doppler area, which was measured quantitatively by a computerized program (Ultrasonic Imaging Tool; Soongsil University, Seoul, Korea). The grade (0, no signal; 1, less than 5%; 2, 5-25%; 3, more than 25%) and flow pattern (intratumoral, detour, basket, and mixed) of tumoral vascularity were analyzed. Peak time of contrast-enhancement was measured on each tumor. After injection of contrast agent, tumoral flow signals increased in all lesions (100%). At unenhanced harmonic PDUS, flow signals were detected in 17 HCCs (52%); 15 tumors (46%) demonstrated grade 1 vascularity; and two (6%), grade 2. At contrast-enhanced harmonic PDUS, all tumors were detected vascularity; five (15%) were grade 1; eight (24%), grade 2; and 20 (61%), grade 3. Flow patterns were demonstated as follows at unenhanced harmonic PDUS; intratumoral pattern in 13 tumors (76%), detour in 2 (12%), and basket in 2 (12%). After injection of contrast agent, intratumoral pattern in 7 tumors (21%), detour 0 (0%), basket in 3 (9%) and mixed in 23 (70%) were demonstrated. Peak time of enhancement after injection of contrast agent was 30- 90 seconds in majority of the patients. Contrast-enhanced harmonic PDUS would be valuable in depiction of vascularity and characterization of flow pattern in HCC.

Neuronal sFlt1 and Vegfaa determine venous sprouting and spinal cord vascularization

DEFF Research Database (Denmark)

Wild, Raphael; Klems, Alina; Takamiya, Masanari

2017-01-01

Formation of organ-specific vasculatures requires cross-talk between developing tissue and specialized endothelial cells. Here we show how developing zebrafish spinal cord neurons coordinate vessel growth through balancing of neuron-derived Vegfaa, with neuronal sFlt1 restricting Vegfaa......-Kdrl mediated angiogenesis at the neurovascular interface. Neuron-specific loss of flt1 or increased neuronal vegfaa expression promotes angiogenesis and peri-neural tube vascular network formation. Combining loss of neuronal flt1 with gain of vegfaa promotes sprout invasion into the neural tube. On loss...... of neuronal flt1, ectopic sprouts emanate from veins involving special angiogenic cell behaviours including nuclear positioning and a molecular signature distinct from primary arterial or secondary venous sprouting. Manipulation of arteriovenous identity or Notch signalling established that ectopic sprouting...

Improved Wojcik's eavesdropping attack on ping-pong protocol without eavesdropping-induced channel loss

International Nuclear Information System (INIS)

Zhang Zhanjun; Li Yong; Man Zhongxiao

2005-01-01

The eavesdropping scheme proposed by Wojcik [Phys. Rev. Lett. 90 (2003) 157901] on the ping-pong protocol [Phys. Rev. Lett. 89 (2002) 187902] is improved by constituting a new set of attack operations. The improved scheme has a zero eavesdropping-induced channel loss and produces perfect anticorrelation. Therefore, the eavesdropper Eve can safely attack all the transmitted bits and the eavesdropping information gain can always exceed the legitimate user's information gain in the whole domain of the quantum channel transmission efficiency η, i.e., [0,100%]. This means that the ping-pong protocol can be completely eavesdropped in its original version. But the improvement of the ping-pong protocol security produced by Wojcik is also suitable for our eavesdropping attack

Proatherogenic pathways leading to vascular calcification

International Nuclear Information System (INIS)

Mazzini, Michael J.; Schulze, P. Christian

2006-01-01

Cardiovascular disease is the leading cause of morbidity and mortality in the western world and atherosclerosis is the major common underlying disease. The pathogenesis of atherosclerosis involves local vascular injury, inflammation and oxidative stress as well as vascular calcification. Vascular calcification has long been regarded as a degenerative process leading to mineral deposition in the vascular wall characteristic for late stages of atherosclerosis. However, recent studies identified vascular calcification in early stages of atherosclerosis and its occurrence has been linked to clinical events in patients with cardiovascular disease. Its degree correlates with local vascular inflammation and with the overall impact and the progression of atherosclerosis. Over the last decade, diverse and highly regulated molecular signaling cascades controlling vascular calcification have been described. Local and circulating molecules such as osteopontin, osteoprogerin, leptin and matrix Gla protein were identified as critical regulators of vascular calcification. We here review the current knowledge on molecular pathways of vascular calcification and their relevance for the progression of cardiovascular disease

Early Detection System of Vascular Disease and Its Application Prospect

Directory of Open Access Journals (Sweden)

Huan Liu

2016-01-01

Full Text Available Markers of imaging, structure, and function reflecting vascular damage, integrating a long time accumulation effect of traditional and unrecognized cardiovascular risk factors, can be regarded as surrogate endpoints of target organ damage before the occurrence of clinical events. Prevention of cardiovascular disease requires risk stratification and treatment of traditional risk factors, such as smoking, hypertension, hyperlipidemia, and diabetes. However, traditional risk stratification is not sufficient to provide accurate assessment of future cardiovascular events. Therefore, vascular injury related parameters obtained by ultrasound or other noninvasive devices, as a surrogate parameter of subclinical cardiovascular disease, can improve cardiovascular risk assessment and optimize the preventive treatment strategy. Thus, we will summarize the research progress and clinical application of early assessment technology of vascular diseases in the present review.

Management of bleeding in vascular surgery.

Science.gov (United States)

Chee, Y E; Liu, S E; Irwin, M G

2016-09-01

Management of acute coagulopathy and blood loss during major vascular procedures poses a significant haemostatic challenge to anaesthetists. The acute coagulopathy is multifactorial in origin with tissue injury and hypotension as the precipitating factors, followed by dilution, hypothermia, acidemia, hyperfibrinolysis and systemic inflammatory response, all acting as a self-perpetuating spiral of events. The problem is confounded by the high prevalence of antithrombotic agent use in these patients and intraoperative heparin administration. Trials specifically examining bleeding management in vascular surgery are lacking, and much of the literature and guidelines are derived from studies on patients with trauma. In general, it is recommended to adopt permissive hypotension with a restrictive fluid strategy, using a combination of crystalloid and colloid solutions up to one litre during the initial resuscitation, after which blood products should be administered. A restrictive transfusion trigger for red cells remains the mainstay of treatment except for the high-risk patients, where the trigger should be individualized. Transfusion of blood components should be initiated by clinical evidence of coagulopathy such as diffuse microvascular bleeding, and then guided by either laboratory or point-of-care coagulation testing. Prophylactic antifibrinolytic use is recommended for all surgery where excessive bleeding is anticipated. Fibrinogen and prothrombin complex concentrates administration are recommended during massive transfusion, whereas rFVIIa should be reserved until all means have failed. While debates over the ideal resuscitative strategy continue, the approach to vascular haemostasis should be scientific, rational, and structured. As far as possible, therapy should be monitored and goal directed. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The use of acoustically tuned resonators to improve the sound transmission loss of double-panel partitions

Science.gov (United States)

Mason, J. M.; Fahy, F. J.

1988-07-01

Double-leaf partitions are often utilized in situations requiring low weight structures with high transmission loss, an example of current interest being the fuselage walls of propeller-driven aircraft. In this case, acoustic excitation is periodic and, if one of the frequencies of excitation lies in the region of the fundamental mass-air-mass frequency of the partition, insulation performance is considerably less than desired. The potential effectiveness of tuned Helmholtz resonators connected to the partition cavity is investigated as a method of improving transmission loss. This is demonstrated by a simple theoretical model and then experimentally verified. Results show that substantial improvements may be obtained at and around the mass-air-mass frequency for a total resonator volume 15 percent of the cavity volume.

A High Precision Comprehensive Evaluation Method for Flood Disaster Loss Based on Improved Genetic Programming

Institute of Scientific and Technical Information of China (English)

ZHOU Yuliang; LU Guihua; JIN Juliang; TONG Fang; ZHOU Ping

2006-01-01

Precise comprehensive evaluation of flood disaster loss is significant for the prevention and mitigation of flood disasters. Here, one of the difficulties involved is how to establish a model capable of describing the complex relation between the input and output data of the system of flood disaster loss. Genetic programming (GP) solves problems by using ideas from genetic algorithm and generates computer programs automatically. In this study a new method named the evaluation of the grade of flood disaster loss (EGFD) on the basis of improved genetic programming (IGP) is presented (IGPEGFD). The flood disaster area and the direct economic loss are taken as the evaluation indexes of flood disaster loss. Obviously that the larger the evaluation index value, the larger the corresponding value of the grade of flood disaster loss is. Consequently the IGP code is designed to make the value of the grade of flood disaster be an increasing function of the index value. The result of the application of the IGP-EGFD model to Henan Province shows that a good function expression can be obtained within a bigger searched function space; and the model is of high precision and considerable practical significance.Thus, IGP-EGFD can be widely used in automatic modeling and other evaluation systems.

The impact of various scaffold components on vascularized bone constructs.

Science.gov (United States)

Eweida, Ahmad; Schulte, Matthias; Frisch, Oliver; Kneser, Ulrich; Harhaus, Leila

2017-06-01

Bone tissue engineering is gaining more interest in the field of craniofacial surgery where continuous efforts are being made to improve the outcomes via modulation of the scaffold components. In an in vitro three dimensional (3D) culture, the effect of bone morphogenic protein 2 (BMP2, 60 μg/ml) and the effect of different cell seeding densities (0.25, 0.5, and 1 × 104) of rat mesenchymal stem cells seeded on nanocrystalline hydroxyapatite in silica gel matrix (Nanobone ® ) on the cell viability and differentiation were studied. Alkaline phosphatase and viability assays were performed at day 7, day 14, and day 21 to assess the differentiation and the relative fraction of viable cells in the 3D cell cultures. In a subsequent in vivo study, we examined the effect of axial vascularization, the scaffold's particle size and the nature of the matrix (collagen type I vs. diluted fibrin) on vascularization and tissue generation in vascularized bone construct in rats. Regarding vascularization, we compared constructs vascularized randomly by extrinsic vascularization from the periphery of the implanted construct with others vascularized axially via an implanted arteriovenous loop (AVL). Regarding the particle size, we compared constructs having a scaffold particle size of 0.2 mm (powder) with other constructs having a particle size of 2 × 0.6 mm (granules). Regarding the matrix we compared constructs having a collagen matrix with others having a fibrin matrix. Various groups were compared regarding the amount of tissue generation, vascularization, and cellular proliferation. The initial seeding density had a temporary and minimal effect on the overall osteogenic differentiation of the cells. On the contrary, adding BMP2 in a concentration of 60 μg/ml over one week led to an overall enhanced osteogenic differentiation despite depressed cell viability. Axial vascularization was mandatory for efficient tissue formation and vascularization of the bone construct

Phenotypic modulation of smooth muscle cells during formation of neointimal thickenings following vascular injury.

Science.gov (United States)

Thyberg, J

1998-07-01

Smooth muscle cells build up the media of mammalian arteries and constitute one of the principal cell types in atherosclerotic and restenotic lesions. Accordingly, they show a high degree of plasticity and are able to shift from a differentiated, contractile phenotype to a less differentiated, synthetic phenotype, and then back again. This modulation occurs as a response to vascular injury and includes a prominent structural reorganization with loss of myofilaments and formation of an extensive endoplasmic reticulum and a large Golgi complex. At the same time, the expression of cytoskeletal proteins and other gene products is altered. As a result, the cells lose their contractility and become able to migrate from the media to the intima, proliferate, and secrete extracellular matrix components, thereby contributing to the formation of intimal thickenings. The mechanisms behind this change in morphology and function of the smooth muscle cells are still incompletely understood. A crucial role has been ascribed to basement membrane proteins such as laminin and collagen type IV and adhesive proteins such as fibronectin. A significant role is also played by mitogenic proteins such as platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF). An improved knowledge of the regulation of smooth muscle differentiated properties represents an important part in the search for new methods of prevention and treatment of vascular disease.

Vascular Remodeling in Experimental Hypertension

Directory of Open Access Journals (Sweden)

Norma R. Risler

2005-01-01

Full Text Available The basic hemodynamic abnormality in hypertension is an increased peripheral resistance that is due mainly to a decreased vascular lumen derived from structural changes in the small arteries wall, named (as a whole vascular remodeling. The vascular wall is an active, flexible, and integrated organ made up of cellular (endothelial cells, smooth muscle cells, adventitia cells, and fibroblasts and noncellular (extracellular matrix components, which in a dynamic way change shape or number, or reorganize in response to physiological and pathological stimuli, maintaining the integrity of the vessel wall in physiological conditions or participating in the vascular changes in cardiovascular diseases such as hypertension. Research focused on new signaling pathways and molecules that can participate in the mechanisms of vascular remodeling has provided evidence showing that vascular structure is not only affected by blood pressure, but also by mechanisms that are independent of the increased pressure. This review will provide an overview of the evidence, explaining some of the pathophysiologic mechanisms participating in the development of the vascular remodeling, in experimental models of hypertension, with special reference to the findings in spontaneously hypertensive rats as a model of essential hypertension, and in fructose-fed rats as a model of secondary hypertension, in the context of the metabolic syndrome. The understanding of the mechanisms producing the vascular alterations will allow the development of novel pharmacological tools for vascular protection in hypertensive disease.

Diabetic retinopathy: loss of neuroretinal adaptation to the diabetic metabolic environment

Science.gov (United States)

Abcouwer, Steven F.; Gardner, Thomas W.

2014-01-01

Diabetic retinopathy (DR) impairs vision of patients with type 1 and type 2 diabetes, associated with vascular dysfunction and occlusion, retinal edema, hemorrhage, and inappropriate growth of new blood vessels. The recent success of biologic treatments targeting vascular endothelial growth factor (VEGF) demonstrates that treating the vascular aspects in the later stages of the disease can preserve vision in many patients. It would also be highly desirable to prevent the onset of the disease or arrest its progression at a stage preceding the appearance of overt microvascular pathologies. The progression of DR is not necessarily linear but may follow a series of steps that evolve over the course of multiple years. Abundant data suggest that diabetes affects the entire neurovascular unit of the retina, with an early loss of neurovascular coupling, gradual neurodegeneration, gliosis, and neuroinflammation before observable vascular pathologies. In this article, we consider the pathology of diabetic retinopathy from the point of view that diabetes causes measurable dysfunctions in the complex integral network of cell types that produce and maintain human vision. PMID:24673341

MIXED HYALINE VASCULAR AND PLASMA CELL TYPE CASTLEMAN’S DISEASE: REPORT OF A CASE

Directory of Open Access Journals (Sweden)

F. Asgarani

2006-05-01

Full Text Available Castleman’s disease (angiofollicular lymphoid hyperplasia includes a heterogeneous group of lymphoproliferative disorders. The cause of this disease remains uncertain. There are two types of localized Castleman’s disease: the more common hyaline vascular and the plasma cell types. Mixed variant is an uncommon localized lesion in general population. The lesions can occur in any part of the body that contains lymphoid tissue, although seventy percent are found in the anterior mediastinum. We report a thirty years old boy with Castleman’s disease who presented with fever, anorexia, weight loss,sweating, anemia and abdominal mass. The histologic examination of the biopsy specimens revealed a mixed hyaline vascular and plasma cell type of Castleman’s disease.

Regional cerebral blood flow in vascular depression assessed by 123I-IMP SPECT

International Nuclear Information System (INIS)

Kimura, Mahito; Shimoda, Kengo; Mizumura, Sunao; Tateno, Amane; Fujito, Tatsuma; Mori, Takao; Endo, Shunkichi

2003-01-01

As the prevalence of white matter hyperintensities detected on T2 weighted MRI scans in patients with late-onset depression is higher than that in nondepressed patients, the concept of ''vascular depression'' (VDep) was introduced in 1997. However, the pathology of vascular depression has not been clarified. This study examined the differences in functional imaging between vascular and non-vascular depression (non-VDep). We utilized 123 I-IMP single photon emission computed tomography (SPECT) to compare regional cerebral blood flows (rCBF) between 9 patients with VDep (Krishnan criteria) and 11 age- and sex-matched patients with non-VDep in both depressed and remitted states. In both VDep and non-VDep patients, mean rCBF increased significantly as depression improved, partially aided by changes in left anterior temporal blood flow. In addition, compared to non-VDep patients, the left anterior frontal rCBF for VDep patients was significantly lower in both depressed and remitted states. Left anterior temporal rCBF therefore appears to represent a state marker that increases as symptoms associated with late-onset depression improve, regardless of vascular changes. Furthermore, in VDep patients, left anterior frontal rCBF was low in both states compared to non-VDep patients, and might not only represent a trait marker, but also correlated with the duration of disease and likelihood of recurrence and relapse. (author)

Hospital costs associated with surgical site infections in general and vascular surgery patients.

Science.gov (United States)

Boltz, Melissa M; Hollenbeak, Christopher S; Julian, Kathleen G; Ortenzi, Gail; Dillon, Peter W

2011-11-01

Although much has been written about excess cost and duration of stay (DOS) associated with surgical site infections (SSIs) after cardiothoracic surgery, less has been reported after vascular and general surgery. We used data from the National Surgical Quality Improvement Program (NSQIP) to estimate the total cost and DOS associated with SSIs in patients undergoing general and vascular surgery. Using standard NSQIP practices, data were collected on patients undergoing general and vascular surgery at a single academic center between 2007 and 2009 and were merged with fully loaded operating costs obtained from the hospital accounting database. Logistic regression was used to determine which patient and preoperative variables influenced the occurrence of SSIs. After adjusting for patient characteristics, costs and DOS were fit to linear regression models to determine the effect of SSIs. Of the 2,250 general and vascular surgery patients sampled, SSIs were observed in 186 inpatients. Predisposing factors of SSIs were male sex, insulin-dependent diabetes, steroid use, wound classification, and operative time (P surgery. Although the excess costs and DOS associated with SSIs after general and vascular surgery are somewhat less, they still represent substantial financial and opportunity costs to hospitals and suggest, along with the implications for patient care, a continuing need for cost-effective quality improvement and programs of infection prevention. Copyright © 2011 Mosby, Inc. All rights reserved.

Creation of a Bioengineered Skin Flap Scaffold with a Perfusable Vascular Pedicle.

Science.gov (United States)

Jank, Bernhard J; Goverman, Jeremy; Guyette, Jacques P; Charest, Jon M; Randolph, Mark; Gaudette, Glenn R; Gershlak, Joshua R; Purschke, Martin; Javorsky, Emilia; Nazarian, Rosalynn M; Leonard, David A; Cetrulo, Curtis L; Austen, William G; Ott, Harald C

2017-07-01

Full-thickness skin loss is a challenging problem due to limited reconstructive options, demanding 75 million surgical procedures annually in the United States. Autologous skin grafting is the gold standard treatment, but results in donor-site morbidity and poor aesthetics. Numerous skin substitutes are available on the market to date, however, none truly functions as full-thickness skin due to lack of a vascular network. The creation of an autologous full-thickness skin analogue with a vascular pedicle would result in a paradigm shift in the management of wounds and in reconstruction of full-thickness skin defects. To create a clinically relevant foundation, we generated an acellular skin flap scaffold (SFS) with a perfusable vascular pedicle of clinically relevant size by perfusion decellularization of porcine fasciocutaneous flaps. We then analyzed the yielded SFS for mechanical properties, biocompatibility, and regenerative potential in vitro and in vivo. Furthermore, we assessed the immunological response using an in vivo model. Finally, we recellularized the vascular compartment of an SFS and reconnected it to a recipient's blood supply to test for perfusability. Perfusion decellularization removed all cellular components with preservation of native extracellular matrix composition and architecture. Biaxial testing revealed preserved mechanical properties. Immunologic response and biocompatibility assessed via implantation and compared with native xenogenic skin and commercially available dermal substitutes revealed rapid neovascularization and complete tissue integration. Composition of infiltrating immune cells showed no evidence of allorejection and resembled the inflammatory phase of wound healing. Implantation into full-thickness skin defects demonstrated good tissue integration and skin regeneration without cicatrization. We have developed a protocol for the generation of an SFS of clinically relevant size, containing a vascular pedicle, which can be

Neuroprotection, learning and memory improvement of a standardized extract from Renshen Shouwu against neuronal injury and vascular dementia in rats with brain ischemia.

Science.gov (United States)

Wan, Li; Cheng, Yufang; Luo, Zhanyuan; Guo, Haibiao; Zhao, Wenjing; Gu, Quanlin; Yang, Xu; Xu, Jiangping; Bei, Weijian; Guo, Jiao

2015-05-13

The Renshen Shouwu capsule (RSSW) is a patented Traditional Chinese Medicine (TCM), that has been proven to improve memory and is widely used in China to apoplexy syndrome and memory deficits. To investigate the neuroprotective and therapeutic effect of the Renshen Shouwu standardized extract (RSSW) on ischemic brain neuronal injury and impairment of learning and memory related to Vascular Dementia (VD) induced by a focal and global cerebral ischemia-reperfusion injury in rats. Using in vivo rat models of both focal ischemia/reperfusion (I/R) injuries induced by a middle cerebral artery occlusion (MCAO), and VD with transient global brain I/R neuronal injuries induced by a four-vessel occlusion (4-VO) in Sprague-Dawley (SD) rats, RSSW (50,100, and 200 mg kg(-1) body weights) and Egb761® (80 mg kg(-1)) were administered orally for 20 days (preventively 6 days+therapeutically 14 days) in 4-VO rats, and for 7 days (3 days preventively+4 days therapeutically) in MCAO rats. Learning and memory behavioral performance was assayed using a Morris water maze test including a place navigation trial and a spatial probe trial. Brain histochemical morphology and hippocampal neuron survival was quantified using microscope assay of a puffin brain/hippocampus slice with cresyl violet staining. MCAO ischemia/reperfusion caused infarct damage in rat brain tissue. 4-VO ischemia/reperfusion caused a hippocampal neuronal lesion and learning and memory deficits in rats. Administration of RSSW (50, 100, and 200mg/kg) or EGb761 significantly reduced the size of the insulted brain hemisphere lesion and improved the neurological behavior of MCAO rats. In addition, RSSW markedly reduced an increase in the brain infarct volume from an I/R-induced MCAO and reduced the cerebral water content in a dose-dependent way. Administration of RSSW also increased the pyramidal neuronal density in the hippocampus of surviving rats after transient global brain ischemia and improved the learning and memory

Vascular anatomy of the spinal cord

International Nuclear Information System (INIS)

Thron, A.K.

1988-01-01

The book summarizes the anatomic guidelines of external blood supply to the spinal cord. The basic principles of arterial supply and venous drainage are illustrated by explicit schemes for quick orientation. In the first part of the book, systematic radiologic-anatomic investigations of the superficial and deep vessels of all segments of the spinal cord are introduced. The microvascular morphology is portrayed by numerous microradiographic sections in all three dimensions without overshadowing. The three-dimensional representation of the vascular architecture illustrates elementary outlines and details of arterial territories, anastomotic cross-linking as well as the capillary system, particularly the hitherto unknown structure of the medullary venous system with its functionally important anastomoses and varying regional structures. These often now radiologic-anatomic findings are discussed as to their functional and pathophysiologic impact and constitute the basic on which to improve one's understanding of vascular syndromes of the spinal cord

Cocoa, blood pressure, and vascular function.

Science.gov (United States)

Sudano, Isabella; Flammer, Andreas J; Roas, Susanne; Enseleit, Frank; Ruschitzka, Frank; Corti, Roberto; Noll, Georg

2012-08-01

The consumption of a high amount of fruits and vegetables was found to be associated with a lower risk of coronary heart disease and stroke. Epidemiologically, a similar relationship has been found with cocoa, a naturally polyphenol-rich food. Obviously, double blind randomized studies are difficult to perform with cocoa and chocolate, respectively. However, intervention studies strongly suggest that cocoa has several beneficial effects on cardiovascular health, including the lowering of blood pressure, the improvement of vascular function and glucose metabolism, and the reduction of platelet aggregation and adhesion. Several potential mechanisms through which cocoa might exert its positive effects have been proposed, among them activation of nitric oxide synthase, increased bioavailability of nitric oxide as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on blood pressure and vascular function.

Dark chocolate consumption improves leukocyte adhesion factors and vascular function in overweight men.

Science.gov (United States)

Esser, Diederik; Mars, Monica; Oosterink, Els; Stalmach, Angelique; Müller, Michael; Afman, Lydia A

2014-03-01

Flavanol-enriched chocolate consumption increases endothelium-dependent vasodilation. Most research so far has focused on flow-mediated dilation (FMD) only; the effects on other factors relevant to endothelial health, such as inflammation and leukocyte adhesion, have hardly been addressed. We investigated whether consumption of regular dark chocolate also affects other markers of endothelial health, and whether chocolate enrichment with flavanols has additional benefits. In a randomized double-blind crossover study, the effects of acute and of 4 wk daily consumption of high flavanol chocolate (HFC) and normal flavanol chocolate (NFC) on FMD, augmentation index (AIX), leukocyte count, plasma cytokines, and leukocyte cell surface molecules in overweight men (age 45-70 yr) were investigated. Sensory profiles and motivation scores to eat chocolate were also collected. Findings showed that a 4 wk chocolate intake increased FMD by 1%, which was paralleled by a decreased AIX of 1%, decreased leukocyte cell count, decreased plasma sICAM1 and sICAM3, and decreased leukocyte adhesion marker expression (Peffect), with no difference between HFC and NFC consumption. Flavanol enrichment did affect taste and negatively affected motivation to consume chocolate. This study provides new insights on how chocolate affects endothelial health by demonstrating that chocolate consumption, besides improving vascular function, also lowers the adherence capacity of leukocytes in the circulation.

Coexistence of pheochromocytoma with uncommon vascular lesions

Directory of Open Access Journals (Sweden)

Sunil Kumar Kota

2012-01-01

Full Text Available Background: Pheochromocytoma/paragangliomas have been described to be associated with rare vascular abnormalities like renal artery stenosis. Coexistence of physiologically significant renal artery lesions is a compounding factor that alters management and prognosis of pheochromocytoma patients. Apart from individual case reports, data on such association in Indian population is not available. The aim of this study is to find the nature and prevalence of associated vascular abnormalities. Materials and Methods: From 1990 to 2010, a total of 50 patients were diagnosed with pheochromocytoma/paragangliomas. Hospital charts of these patients were reviewed retrospectively to identify those with unusual vascular abnormalities. Available literature was also reviewed. Results: Of the 50 patients with pheochromocytoma, 7 (14% had coexisting vascular lesions including renal artery stenosis in 4, aortoarteritis in 1, aortic aneurysm in 1 and inferior vena cava thrombosis in 1. Pheochromocytoma was adrenal in 42 and extra adrenal in 8. Laparoscopic adrenalectomy was done in the patients. One patient with renal artery stenosis due to intimal fibrosis was subjected to percutaneous balloon angioplasty; the other three improved after adrenalectomy and lysis of fibrous adhesive bands. The patient with aortoarteritos was treated with oral steroids. Inferior vena cava thrombosis was reversed with anticoagulants. The patient with abdominal aortic aneurysm was advised for annual follow-up on account of its size of 4.5 cm and asymptomatic presentation. Conclusion: There are multiple mechanisms that can lead to renal artery stenosis and other vascular abnormalities in a case of pheochromocytoma. A high index of suspicion is necessary to enable both entities to be diagnosed preoperatively and allow proper planning of surgical therapy. Incomplete diagnosis may lead to persistent hypertension postoperatively in a case of associated renal artery stenosis.

Vascular injuries of the upper extremity Lesões vasculares de membros superiores

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Raafat Shalabi

2006-12-01

Full Text Available OBJECTIVE: This study analyzes the causes of injuries, presentations, surgical approaches, outcome and complications of vascular trauma of the upper limbs, in spite of limited hospital resources. METHODS: A 5-year retrospective analysis. From 01/01/2001 to 31/12/2005, 165 patients were operated for vascular injuries at King Fahd Hospital, Medina, Saudi Arabia. Of all peripheral vascular trauma patients (115, upper limb trauma was present in 58. Diagnosis was made by physical examination and hand-held Doppler alone or in combination with Doppler scan/angiography. Primary vascular repair was performed whenever possible; otherwise, the interposition vein graft was used. Fasciotomy was considered when required. Patients with unsalvageable lower extremity injury requiring primary amputation were excluded from the study. RESULTS: Fifty patients were male (86% and eight were female (14%, aged between 2.5-55 years (mean 23 years. Mean duration of presentation was 8 h after the injury. The most common etiological factor was road traffic accidents, accounting for 50.5% in the blunt trauma group and 33% among all penetrating and stab wound injuries. Incidence of concomitant orthopedic injuries was very high in our study (51%. The brachial artery was the most affected (51%. Interposition vein grafts were used in 53% of the cases. Limb salvage rate was 100%. CONCLUSION: Patients who suffer vascular injuries of the upper extremities should be transferred to vascular surgery centers as soon as possible. Decisive management of peripheral vascular trauma will maximize patient survival and limb salvage. Priorities must be established in the management of associated injuries, and delay must be avoided when ischemic changes are present.OBJETIVO: Este estudo analisa as causas de lesões, apresentação, abordagens cirúrgicas, desfechos e complicações do trauma vascular de membros superiores, apesar de recursos hospitalares limitados. MÉTODOS: An

Leveraging corporate social responsibility to improve consumer safety of dietary supplements sold for weight loss and muscle building.

Science.gov (United States)

Kulkarni, Anvita; Huerto, Ryan; Roberto, Christina A; Austin, S Bryn

2017-03-01

The potential dangers associated with dietary supplements sold for weight loss and muscle building are well documented and increasingly garnering the attention of the media, public, and government leaders. Public health professionals have an opportunity to improve population health in the context of dietary supplement use by translating scientific evidence into action. In this commentary, we discuss the potential to motivate corporate social responsibility (CSR) among manufacturers and retailers of dietary supplements sold for weight loss and muscle building. We examine levers available to public health professionals for generating voluntary corporate self-regulation by reviewing examples from successful CSR initiatives in other domains of public health and offering recommendations highlighting effective advocacy strategies. We encourage public health professionals to use one or multiple advocacy strategies to improve consumer protections for dietary supplements sold for weight loss and muscle building.

CARDIO-VASCULAR RISK FACTORS IN ELDERLY PATIENTS WITH DISEASES OF THE STOMATOGNATHIC SYSTEM

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Botez C

2011-09-01

Full Text Available The association between dental and cardio-vascular diseases is essential as both are highly prevalent. Finding a possible causal relation between cardiovascular disease and chronic periodontal pathology, known to cause tooth loss, is therefore essential. The existence of some risk factors, such as smoking, bacterial infections, malnutrition and nutritional deficiencies, may explain the associations observed between cardio-vascular and oral pathologies. In the case of dental diseases, acceleration of atherosclerosis is supported by the role played by infections. The study – performed between 2008-2009 – analyzed 45 cases, selected from the patients hospitalized in the Medical Clinics of the Military Hospital of Ia[i. The patients included in the study suffered from arterial hypertension (HTA, cardiac insufficiency, ischemic cardiopathy, pectoral angina and subacute infectious endocarditis. All were subjected to a stomatological examination, for establishing their dental hygiene, the stomatological diseases they had had and the treatments performed. There are several ways in which infections of the oral cavity lead to cardiovascular disease. These include: transitory bacteriemia; inflammation and vascular lesions; diet and smoking.

Angiogenesis Research to Improve Therapies for Vascular Leak Syndromes, Intra-Abdominal Adhesions, and Arterial Injuries

National Research Council Canada - National Science Library

Folkman, Judah; Puder, Mark; Bischoff, Joyce

2006-01-01

...) to develop angiogenesis inhibitors which would inhibit post-operative abdominal adhesions; and (iii) to isolate endothelial progenitor cells from blood capable of being expanded in vitro and applied to vascular grafts...

Angiogenesis Research to Improve Therapies for Vascular Leak Syndromes, Intra-Abdominal Adhesions, and Arterial Injuries

National Research Council Canada - National Science Library

Folkman, Judah; Puder, Mark; Bischoff, Joyce

2007-01-01

...) to develop angiogenesis inhibitors which would inhibit post-operative abdominal adhesions; and, (iii) to isolate endothelial progenitor cells from blood, capable of being expanded in vitro and applied to vascular grafts...

Angiogenesis Research to Improve Therapies for Vascular Leak Syndromes, Intra-abdominal Adhesions, and Arterial Injuries

National Research Council Canada - National Science Library

Folkman, Judah

2008-01-01

...) to develop angiogenesis inhibitors which would inhibit post-operative abdominal adhesions; and, (iii) to isolate endothelial progenitor cells from blood, capable of being expanded in vitro and applied to vascular grafts...

Pediatric central nervous system vascular malformations

Energy Technology Data Exchange (ETDEWEB)

Burch, Ezra A. [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Orbach, Darren B. [Boston Children' s Hospital, Neurointerventional Radiology, Boston, MA (United States)

2015-09-15

Pediatric central nervous system (CNS) vascular anomalies include lesions found only in the pediatric population and also the full gamut of vascular lesions found in adults. Pediatric-specific lesions discussed here include infantile hemangioma, vein of Galen malformation and dural sinus malformation. Some CNS vascular lesions that occur in adults, such as arteriovenous malformation, have somewhat distinct manifestations in children, and those are also discussed. Additionally, children with CNS vascular malformations often have associated broader vascular conditions, e.g., PHACES (posterior fossa anomalies, hemangioma, arterial anomalies, cardiac anomalies, eye anomalies and sternal anomalies), hereditary hemorrhagic telangiectasia, and capillary malformation-arteriovenous malformation syndrome (related to the RASA1 mutation). The treatment of pediatric CNS vascular malformations has greatly benefited from advances in endovascular therapy, including technical advances in adult interventional neuroradiology. Dramatic advances in therapy are expected to stem from increased understanding of the genetics and vascular biology that underlie pediatric CNS vascular malformations. (orig.)

Pediatric central nervous system vascular malformations

International Nuclear Information System (INIS)

Burch, Ezra A.; Orbach, Darren B.

2015-01-01

Pediatric central nervous system (CNS) vascular anomalies include lesions found only in the pediatric population and also the full gamut of vascular lesions found in adults. Pediatric-specific lesions discussed here include infantile hemangioma, vein of Galen malformation and dural sinus malformation. Some CNS vascular lesions that occur in adults, such as arteriovenous malformation, have somewhat distinct manifestations in children, and those are also discussed. Additionally, children with CNS vascular malformations often have associated broader vascular conditions, e.g., PHACES (posterior fossa anomalies, hemangioma, arterial anomalies, cardiac anomalies, eye anomalies and sternal anomalies), hereditary hemorrhagic telangiectasia, and capillary malformation-arteriovenous malformation syndrome (related to the RASA1 mutation). The treatment of pediatric CNS vascular malformations has greatly benefited from advances in endovascular therapy, including technical advances in adult interventional neuroradiology. Dramatic advances in therapy are expected to stem from increased understanding of the genetics and vascular biology that underlie pediatric CNS vascular malformations. (orig.)

ROBO4-Mediated Vascular Integrity Regulates the Directionality of Hematopoietic Stem Cell Trafficking

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Stephanie Smith-Berdan

2015-02-01

Full Text Available Despite the use of hematopoietic stem cells (HSCs in clinical therapy for over half a century, the mechanisms that regulate HSC trafficking, engraftment, and life-long persistence after transplantation are unclear. Here, we show that the vascular endothelium regulates HSC trafficking into and out of bone marrow (BM niches. Surprisingly, we found that instead of acting as barriers to cellular entry, vascular endothelial cells, via the guidance molecule ROBO4, actively promote HSC translocation across vessel walls into the BM space. In contrast, we found that the vasculature inhibits the reverse process, as induced vascular permeability led to a rapid increase in HSCs in the blood stream. Thus, the vascular endothelium reinforces HSC localization to BM niches both by promoting HSC extravasation from blood-to-BM and by forming vascular barriers that prevent BM-to-blood escape. Our results uncouple the mechanisms that regulate the directionality of HSC trafficking and show that the vasculature can be targeted to improve hematopoietic transplantation therapies.

Coincidence of calcified carotid atheromatous plaque, osteoporosis, and periodontal bone loss in dental panoramic radiographs

International Nuclear Information System (INIS)

Ramesh, Aruna; Ganguly, Rumpa; Soroushian, Sheila

2013-01-01

This study was performed to assess the correlation of calcified carotid atheromatous plaque (CCAP), the mandibular cortical index, and periodontal bone loss in panoramic radiographs. One hundred eighty-five panoramic radiographs with CCAP and 234 without this finding were evaluated by 3 observers for the presence of osseous changes related to osteoporosis and periodontal bone loss. Chi-squared and Mann-Whitney U tests were used to compare the two groups for an association of CCAP with the mandibular cortical index and periodontal bone loss, respectively. There was a statistically significant coincidence of CCAP and osseous changes related to osteopenia/osteoporosis, with a p-value <0.001. There was no statistically significant coincidence of CCAP and periodontal bone loss. When comparing the 2 groups, 'With CCAP' and 'Without CCAP', there was a statistically significant association with the mean body mass index (BMI), number of remaining teeth, positive history of diabetes mellitus, and vascular accidents. There was no statistically significant association with gender or a history of smoking. This study identified a possible concurrence of CCAP and mandibular cortical changes secondary to osteopenia/osteoporosis in panoramic radiographs. This could demonstrate the important role of dental professionals in screening for these systemic conditions, leading to timely and appropriate referrals resulting in early interventions and thus improving overall health.

Osteonecrosis of femoral head: Treatment by core decompression and vascular pedicle grafting

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Babhulkar Sudhir

2009-01-01

Full Text Available Background: Femoral head-preserving core decompression and bone grafting have shown excellent result in preventing collapse. The use of vascularized grafts have shown better clinical results. The vascular pedicle bone graft is an easy to perform operation and does not require special equipment. We analyzed and report a series of patients of osteonecrosis of femoral head treated by core decompression and vascular pedicle grafting of part of iliac crest based on deep circumflex iliac vessels. Materials and Methods: The article comprises of the retrospective study of 31 patients of osteonecrosis of femoral head in stage II and III treated with core decompression and vascular pedicle grafting by using part of iliac crest with deep circumflex iliac vessels from January 1990 to December 2005. The young patients with a mean age 32 years (18-52 years with a minimum follow-up of five years were included for analysis. Sixteen patients had osteonecrosis following alcohol abuse, 12 patients following corticosteroid consumption, 3 patients had idiopathic osteonecrosis. Nine patients were stage IIB, and 22 patients were stage IIIC according to ARCO′s system. The core decompression and vascular pedicle grafting was performed by anterior approach by using part of iliac crest with deep circumflex iliac vessels. Results: Digital subtraction arteriography performed in 9 patients at the end of 12 weeks showed the patency of deep circumflex artery in all cases, and bone scan performed in 6 other patients showed high uptake in the grafted area of the femoral head proving the efficacy of the operative procedure. Out of 31 patients, only one patient progressed to collapse and total joint replacement was advised. At the final follow up period of 5-8 years, Harris Hip Score improved mean ± SD of 28.2 ± 6.4 ( p < 0.05. Forty-eight percent of patients had an improvement in Harris Hip Score of more that 28 points. Conclusion: The core decompression and vascular pedicle

Improved W\\'{o}jcik's Eavesdropping Attack on Ping-Pong Protocol Without Eavesdropping-Induced Channel Loss

OpenAIRE

Zhang, Zhan-jun; Li, Yong; Man, Zhong-xiao

2004-01-01

The eavesdropping scheme proposed by W\\'{o}jcik [Phys. Rev. Lett. {\\bf 90},157901(2003)] on the ping-pong protocol [Phys. Rev. Lett. {\\bf 89}, 187902(2002)] is improved by constituting a new set of attack operations. The improved scheme has a zero eavesdropping-induced channel loss and produces perfect anticorrelation. Therefore, the eavesdropper Eve can safely attack all the transmitted bits and the eavesdropping information gain can always exceed the legitimate user's information gain in th...

Injuries to the vascular endothelium: vascular wall and endothelial dysfunction.

Science.gov (United States)

Fisher, Mark

2008-01-01

Vascular endothelial injury has multiple elements, and this article focuses on ischemia-related processes that have particular relevance to ischemic stroke. Distinctions between necrotic and apoptotic cell death provide a basic science context in which to better understand the significance of classical core and penumbra concepts of acute stroke, with apoptotic processes particularly prominent in the penumbra. The mitochondria are understood to serve as a reservoir of proteins that mediate apoptosis. Oxidative stress pathways generating reactive oxygen species (ROS) are prominent in endothelial injury, both ischemic and nonischemic, with prominent roles of enzyme- and nonenzymemediated pathways; mitochondria once again have a critical role, particularly in the nonenzymatic pathways generating ROS. Inflammation also contributes to vascular endothelial injury, and endothelial cells have the capacity to rapidly increase expression of inflammatory mediators following ischemic challenge; this leads to enhanced leukocyte-endothelial interactions mediated by selectins and adhesion molecules. Preconditioning consists of a minor version of an injurious event, which in turn may protect vascular endothelium from injury following a more substantial event. Presence of the blood-brain barrier creates unique responses to endothelial injury, with permeability changes due to impairment of endothelial-matrix interactions compounding altered vasomotor tone and tissue perfusion mediated by nitric oxide. Pharmacological protection against vascular endothelial injury can be provided by several of the phosphodiesterases (cilostazol and dipyridamole), along with statins. Optimal clinical responses for protection of brain vascular endothelium may use preconditioning as a model, and will likely require combined protection against apoptosis, ROS, and inflammation.

Heart rate recovery improves after weight loss in overweight and obese women with polycystic ovary syndrome.

Science.gov (United States)

Thomson, Rebecca L; Buckley, Jonathan D; Noakes, Manny; Clifton, Peter M; Norman, Robert J; Brinkworth, Grant D

2010-03-01

To determine the effects of weight loss on heart rate recovery (HRR) in overweight women with polycystic ovary syndrome (PCOS). A 10-week prospective clinical intervention. Clinical research unit. Fifty-seven overweight and obese women with PCOS (age: 29.8 +/- 0.8 years; body mass index [BMI] 36.2 +/- 0.7 kg/m(2)). A dietary plan of 5-6 MJ/day ( approximately 30% energy restricted). Heart rate recovery (defined as the reduction in heart rate after 1 minute from peak heart rate after a graded treadmill test to exhaustion), weight, waist circumference, blood pressure, glucose, insulin, homeostasis model assessment of insulin resistance, and sex steroids before and after the intervention. The mean percentage of weight loss was (-6.7 +/- 0.4%). There were significant reductions in waist circumference (-6.9 +/- 0.6 cm), blood pressure (-4.9/-2.5 +/- 1.2/1.2 mm Hg), fasting insulin (-3.4 +/- 0.7 mU/L), fasting glucose (-0.17 +/- 0.05 mmol/L), homeostasis model assessment of insulin resistance (-0.43 +/- 0.09), T (-0.38 +/- 0.07 nmol/L), free androgen index (-2.86 +/- 0.58), and an increase in sex hormone-binding globulin [SHBG] (5.86 +/- 1.12 nmol/L). The HRR improved from 30.9 +/- 1.1 to 38.0 +/- 1.1 beats/min and that was related to the reduction in body weight (r = -0.34) and waist circumference (r = -0.27). Weight loss in overweight and obese women with PCOS is associated with improvements in HRR, which suggests improved autonomic function. This highlights the importance of weight loss to reduce the cardiovascular disease risk in these women. Crown Copyright 2010. Published by Elsevier Inc. All rights reserved.

Reducing N losses through surface runoff from rice-wheat rotation by improving fertilizer management.

Science.gov (United States)

Cao, Yansheng; Sun, Huifeng; Liu, Yaqin; Fu, Zishi; Chen, Guifa; Zou, Guoyan; Zhou, Sheng

2017-02-01

To better understand N runoff losses from rice-wheat rotation and demonstrate the effectiveness of improved fertilizer management in reducing N runoff losses, a field study was conducted for three consecutive rice-wheat rotations. Nitrogen losses through surface runoff were measured for five treatments, including CK without N application, C200, C300 simulating the conventional practices, CO200, and CO300. Optimum N rate was applied for C200 and CO200, and 30% of chemical fertilizer was substituted with organic fertilizer for CO200 and CO300 with respect to C200 and C300, respectively. Rice season had higher runoff coefficients than wheat season. Approximately 52% of total N was lost as NH 4 + -N in rice season, ranging from 21 to 83%, and in wheat season, the proportion of NO 3 - -N in total N averaged 53% with a variation from 38 to 67%. The N treatments lost less total N in rice season (1.67-10.7 kg N ha -1 ) than in wheat season (1.72-17.1 kg N ha -1 ). These suggested that a key to controlling N runoff losses from rice-wheat rotation was to limit NO 3 - -N accumulation in wheat season. In both seasons, N runoff losses for C200 and CO300 were lower than those for C300. CO200 better cut N losses than C200 and CO300, with 64 and 57% less N in rice and wheat seasons than C300, respectively. Compared with the conventional practices, optimum N inputs integrated with co-application of organic and chemical fertilizers could reduce N runoff losses with a better N balance under rice-wheat rotation.

Role of endoplasmic reticulum stress in the loss of retinal ganglion cells in diabetic retinopathy

Institute of Scientific and Technical Information of China (English)

Liping Yang; Lemeng Wu; Dongmei Wang; Ying Li; Hongliang Dou; Mark OMTso; Zhizhong Ma

2013-01-01

Endoplasmic reticulum stress is closely involved in the early stage of diabetic retinopathy. In the present study, a streptozotocin-induced diabetic animal model was given an intraperitoneal injection of tauroursodeoxycholic acid. Results from immunofluorescent co-localization experiments showed that both caspase-12 protein and c-Jun N-terminal kinase 1 phosphorylation levels significantly in-creased, which was associated with retinal ganglion celldeath in diabetic retinas. The C/ERB ho-mologous protein pathway directly contributed to glial reactivity, and was subsequently responsible for neuronal loss and vascular abnormalities in diabetic retinopathy. Our experimental findings in-dicate that endoplasmic reticulum stress plays an important role in diabetes-induced retinal neu-ronal loss and vascular abnormalities, and that inhibiting the activation of the endoplasmic reticulum stress pathway provides effective protection against diabetic retinopathy.

Long-Lasting Improvements in Liver Fat and Metabolism Despite Body Weight Regain After Dietary Weight Loss

OpenAIRE

Haufe, Sven; Haas, Verena; Utz, Wolfgang; Birkenfeld, Andreas L.; Jeran, Stephanie; Böhnke, Jana; Mähler, Anja; Luft, Friedrich C.; Schulz-Menger, Jeanette; Boschmann, Michael; Jordan, Jens; Engeli, Stefan

2013-01-01

OBJECTIVE Weight loss reduces abdominal and intrahepatic fat, thereby improving metabolic and cardiovascular risk. Yet, many patients regain weight after successful diet-induced weight loss. Long-term changes in abdominal and liver fat, along with liver test results and insulin resistance, are not known. RESEARCH DESIGN AND METHODS We analyzed 50 overweight to obese subjects (46 ± 9 years of age; BMI, 32.5 ± 3.3 kg/m2; women, 77%) who had participated in a 6-month hypocaloric diet and were ra...

Medical Textiles as Vascular Implants and Their Success to Mimic Natural Arteries

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Charanpreet Singh

2015-06-01

Full Text Available Vascular implants belong to a specialised class of medical textiles. The basic purpose of a vascular implant (graft and stent is to act as an artificial conduit or substitute for a diseased artery. However, the long-term healing function depends on its ability to mimic the mechanical and biological behaviour of the artery. This requires a thorough understanding of the structure and function of an artery, which can then be translated into a synthetic structure based on the capabilities of the manufacturing method utilised. Common textile manufacturing techniques, such as weaving, knitting, braiding, and electrospinning, are frequently used to design vascular implants for research and commercial purposes for the past decades. However, the ability to match attributes of a vascular substitute to those of a native artery still remains a challenge. The synthetic implants have been found to cause disturbance in biological, biomechanical, and hemodynamic parameters at the implant site, which has been widely attributed to their structural design. In this work, we reviewed the design aspect of textile vascular implants and compared them to the structure of a natural artery as a basis for assessing the level of success as an implant. The outcome of this work is expected to encourage future design strategies for developing improved long lasting vascular implants.

Cocoa, Blood Pressure, and Vascular Function

Science.gov (United States)

Ludovici, Valeria; Barthelmes, Jens; Nägele, Matthias P.; Enseleit, Frank; Ferri, Claudio; Flammer, Andreas J.; Ruschitzka, Frank; Sudano, Isabella

2017-01-01

Cardiovascular disease (CVD) represents the most common cause of death worldwide. The consumption of natural polyphenol-rich foods, and cocoa in particular, has been related to a reduced risk of CVD, including coronary heart disease and stroke. Intervention studies strongly suggest that cocoa exerts a beneficial impact on cardiovascular health, through the reduction of blood pressure (BP), improvement of vascular function, modulation of lipid and glucose metabolism, and reduction of platelet aggregation. These potentially beneficial effects have been shown in healthy subjects as well as in patients with risk factors (arterial hypertension, diabetes, and smoking) or established CVD (coronary heart disease or heart failure). Several potential mechanisms are supposed to be responsible for the positive effect of cocoa; among them activation of nitric oxide (NO) synthase, increased bioavailability of NO as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on BP and vascular function. PMID:28824916

Cocoa, Blood Pressure, and Vascular Function

Directory of Open Access Journals (Sweden)

Valeria Ludovici

2017-08-01

Full Text Available Cardiovascular disease (CVD represents the most common cause of death worldwide. The consumption of natural polyphenol-rich foods, and cocoa in particular, has been related to a reduced risk of CVD, including coronary heart disease and stroke. Intervention studies strongly suggest that cocoa exerts a beneficial impact on cardiovascular health, through the reduction of blood pressure (BP, improvement of vascular function, modulation of lipid and glucose metabolism, and reduction of platelet aggregation. These potentially beneficial effects have been shown in healthy subjects as well as in patients with risk factors (arterial hypertension, diabetes, and smoking or established CVD (coronary heart disease or heart failure. Several potential mechanisms are supposed to be responsible for the positive effect of cocoa; among them activation of nitric oxide (NO synthase, increased bioavailability of NO as well as antioxidant, and anti-inflammatory properties. It is the aim of this review to summarize the findings of cocoa and chocolate on BP and vascular function.

Vascular lesions of the vocal fold.

Science.gov (United States)

Gökcan, Kürşat Mustafa; Dursun, Gürsel

2009-04-01

The aim of the study was to present symptoms, laryngological findings, clinical course, management modalities, and consequences of vascular lesions of vocal fold. This study examined 162 patients, the majority professional voice users, with vascular lesions regarding their presenting symptoms, laryngological findings, clinical courses and treatment results. The most common complaint was sudden hoarseness with hemorrhagic polyp. Microlaryngoscopic surgery was performed in 108 cases and the main indication of surgery was the presence of vocal fold mass or development of vocal polyp during clinical course. Cold microsurgery was utilized for removal of vocal fold masses and feeding vessels cauterized using low power, pulsed CO(2) laser. Acoustic analysis of patients revealed a significant improvement of jitter, shimmer and harmonics/noise ratio values after treatment. Depending on our clinical findings, we propose treatment algorithm where voice rest and behavioral therapy is the integral part and indications of surgery are individualized for each patient.

Vascular malformations in pediatrics

International Nuclear Information System (INIS)

Reith, W.; Shamdeen, M.G.

2003-01-01

Vascular malformations are the cause of nearly all non-traumatic intracranial hemorrhage in children beyond the neonatal stage. Therefore, any child presenting with spontaneous intracranial hemorrhage should be evaluated for child abuse and for vascular malformations. Intracerebral malformations of the cerebral vasculature include vein of Galen malformations, arteriovenous malformation (AVM), cavernomas, dural arteriovenous fistulas, venous anomalies (DVA), and capillary teleangiectasies. Although a few familial vascular malformation have been reported, the majority are sporadic. Clinical symptoms, diagnostic and therapeutic options are discussed. (orig.) [de

The predictive value of renal vascular resistance for late renal allograft loss

NARCIS (Netherlands)

de Vries, APJ; van Son, WJ; van der Heide, JJH; Ploeg, RJ; Navis, G; de Jong, PE; Gans, ROB; Bakker, SJL; Gansevoort, RT

The renal artery resistance index (RI), assessed by Doppler ultrasonography, was recently identified as a new risk marker for late renal allograft loss. This finding requires confirmation since RI in that study was not measured at predetermined time points and ultrasonography is operator-dependent.

The predictive value of renal vascular resistance for late renal allograft loss

NARCIS (Netherlands)

de Vries, A. P. J.; van Son, W. J.; Homan van der Heide, J. J.; Ploeg, R. J.; Navis, G.; de Jong, P. E.; Gans, R. O. B.; Bakker, S. J. L.; Gansevoort, R. T.

2006-01-01

The renal artery resistance index (RI), assessed by Doppler ultrasonography, was recently identified as a new risk marker for late renal allograft loss. This finding requires confirmation since RI in that study was not measured at predetermined time points and ultrasonography is operator-dependent.

Exercise training improves physical fitness and vascular function in children with type 1 diabetes

NARCIS (Netherlands)

Seeger, J.P.H.; Thijssen, D.H.J.; Noordam, K.; Cranen, M.E.; Hopman, M.T.E.; Nijhuis-Van der Sanden, M.W.G.

2011-01-01

Children with type 1 diabetes mellitus (DM1) show endothelial dysfunction and mild artery wall thickening compared to their age-matched healthy peers. In this study, we examined the effect of 18-week exercise training on physical fitness and vascular function and structure in children with DM1. We

Imaging and modification of the tumor vascular barrier for improvement in magnetic nanoparticle uptake and hyperthermia treatment efficacy

Science.gov (United States)

Hoopes, P. Jack; Petryk, Alicia A.; Tate, Jennifer A.; Savellano, Mark S.; Strawbridge, Rendall R.; Giustini, Andrew J.; Stan, Radu V.; Gimi, Barjor; Garwood, Michael

2013-02-01

The predicted success of nanoparticle based cancer therapy is due in part to the presence of the inherent leakiness of the tumor vascular barrier, the so called enhanced permeability and retention (EPR) effect. Although the EPR effect is present in varying degrees in many tumors, it has not resulted in the consistent level of nanoparticle-tumor uptake enhancement that was initially predicted. Magnetic/iron oxide nanoparticles (mNPs) have many positive qualities, including their inert/nontoxic nature, the ability to be produced in various sizes, the ability to be activated by a deeply penetrating and nontoxic magnetic field resulting in cell-specific cytotoxic heating, and the ability to be successfully coated with a wide variety of functional coatings. However, at this time, the delivery of adequate numbers of nanoparticles to the tumor site via systemic administration remains challenging. Ionizing radiation, cisplatinum chemotherapy, external static magnetic fields and vascular disrupting agents are being used to modify the tumor environment/vasculature barrier to improve mNP uptake in tumors and subsequently tumor treatment. Preliminary studies suggest use of these modalities, individually, can result in mNP uptake improvements in the 3-10 fold range. Ongoing studies show promise of even greater tumor uptake enhancement when these methods are combined. The level and location of mNP/Fe in blood and normal/tumor tissue is assessed via histopathological methods (confocal, light and electron microscopy, histochemical iron staining, fluorescent labeling, TEM) and ICP-MS. In order to accurately plan and assess mNP-based therapies in clinical patients, a noninvasive and quantitative imaging technique for the assessment of mNP uptake and biodistribution will be necessary. To address this issue, we examined the use of computed tomography (CT), magnetic resonance imaging (MRI), and Sweep Imaging With Fourier Transformation (SWIFT), an MRI technique which provides a

Expression of Vascular Endothelial Growth Factor Receptors in Benign Vascular Lesions of the Orbit: A Case Series.

Science.gov (United States)

Atchison, Elizabeth A; Garrity, James A; Castillo, Francisco; Engman, Steven J; Couch, Steven M; Salomão, Diva R

2016-01-01

Vascular lesions of the orbit, although not malignant, can cause morbidity because of their location near critical structures in the orbit. For the same reason, they can be challenging to remove surgically. Anti-vascular endothelial growth factor (VEGF) drugs are increasingly being used to treat diseases with prominent angiogenesis. Our study aimed to determine to what extent VEGF receptors and their subtypes are expressed on selected vascular lesions of the orbit. Retrospective case series of all orbital vascular lesions removed by one of the authors (JAG) at the Mayo Clinic. A total of 52 patients who underwent removal of vascular orbital lesions. The pathology specimens from the patients were retrieved, their pathologic diagnosis was confirmed, demographic and clinical information were gathered, and sections from vascular tumors were stained with vascular endothelial growth factor receptor (VEGFR), vascular endothelial growth factor receptor type 1 (VEGFR1), vascular endothelial growth factor receptor type 2 (VEGFR2), and vascular endothelial growth factor receptor type 3 (VEGFR3). The existence and pattern of staining with VEGF and its subtypes on these lesions. There were 28 specimens of venous malformations, 4 capillary hemangiomas, 7 lymphatic malformations, and 6 lymphaticovenous malformations. All samples stained with VEGF, 55% stained with VEGFR1, 98% stained with VEGFR2, and 96% stained with VEGFR3. Most (94%) of the VEGFR2 staining was diffuse. Most orbital vascular lesions express VEGF receptors, which may suggest a future target for nonsurgical treatment. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Instrumentalization of Eating Improves Weight Loss Maintenance in Obesity

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Bodil Just Christensen

2017-12-01

Full Text Available Aim: The purpose of this study was to identify psychosocial determinants for maintaining weight loss. Methods: 42 obese individuals who achieved a 12% weight loss before entering a 52-week weight maintenance program were interviewed qualitatively. Psychosocial factors related to weight loss maintenance were identified in two contrasting groups: weight reducers and weight regainers. Groups were defined by health-relevant weight maintenance (additional weight loss > 3% at week 52, n = 9 versus weight gain > 3%, at week 52, n = 20. Results: Weight reducers reported structured meal patterns (p = 0.008, no comfort eating (p = 0.016 and less psychosocial stress (p = 0.04 compared to weight regainers. The ability to instrumentalize eating behavior emerged as an important factor (p = 0.007. Nutritional knowledge, motivation or exercise level did not differ between groups (p > 0.05. Conclusions: Successful weight loss maintenance was associated with an interplay between behavioral, affective and contextual changes. ‘Instrumentalization of eating behavior' seems to be an important element in long-term weight maintenance.

Long-term consequences of developmental vascular defects on retinal vessel homeostasis and function in a mouse model of Norrie disease.

Science.gov (United States)

Beck, Susanne C; Feng, Yuxi; Sothilingam, Vithiyanjali; Garcia Garrido, Marina; Tanimoto, Naoyuki; Acar, Niyazi; Shan, Shenliang; Seebauer, Britta; Berger, Wolfgang; Hammes, Hans-Peter; Seeliger, Mathias W

2017-01-01

Loss of Norrin signalling due to mutations in the Norrie disease pseudoglioma gene causes severe vascular defects in the retina, leading to visual impairment and ultimately blindness. While the emphasis of experimental work so far was on the developmental period, we focus here on disease mechanisms that induce progression into severe adult disease. The goal of this study was the comprehensive analysis of the long-term effects of the absence of Norrin on vascular homeostasis and retinal function. In a mouse model of Norrie disease retinal vascular morphology and integrity were studied by means of in vivo angiography; the vascular constituents were assessed in detailed histological analyses using quantitative retinal morphometry. Finally, electroretinographic analyses were performed to assess the retinal function in adult Norrin deficient animals. We could show that the primary developmental defects not only persisted but developed into further vascular abnormalities and microangiopathies. In particular, the overall vessel homeostasis, the vascular integrity, and also the cellular constituents of the vascular wall were affected in the adult Norrin deficient retina. Moreover, functional analyses indicated to persistent hypoxia in the neural retina which was suggested as one of the major driving forces of disease progression. In summary, our data provide evidence that the key to adult Norrie disease are ongoing vascular modifications, driven by the persistent hypoxic conditions, which are ineffective to compensate for the primary Norrin-dependent defects.

Towards the therapeutic use of vascular smooth muscle progenitor cells.

Science.gov (United States)

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.

Deficiency of superoxide dismutase promotes cerebral vascular hypertrophy and vascular dysfunction in hyperhomocysteinemia.

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Sanjana Dayal

Full Text Available There is an emerging consensus that hyperhomocysteinemia is an independent risk factor for cerebral vascular disease and that homocysteine-lowering therapy protects from ischemic stroke. However, the mechanisms by which hyperhomocysteinemia produces abnormalities of cerebral vascular structure and function remain largely undefined. Our objective in this study was to define the mechanistic role of superoxide in hyperhomocysteinemia-induced cerebral vascular dysfunction and hypertrophy. Unlike previous studies, our experimental design included a genetic approach to alter superoxide levels by using superoxide dismutase 1 (SOD1-deficient mice fed a high methionine/low folate diet to produce hyperhomocysteinemia. In wild-type mice, the hyperhomocysteinemic diet caused elevated superoxide levels and impaired responses to endothelium-dependent vasodilators in cerebral arterioles, and SOD1 deficiency compounded the severity of these effects. The cross-sectional area of the pial arteriolar wall was markedly increased in mice with SOD1 deficiency, and the hyperhomocysteinemic diet sensitized SOD1-deficient mice to this hypertrophic effect. Analysis of individual components of the vascular wall demonstrated a significant increase in the content of smooth muscle and elastin. We conclude that superoxide is a key driver of both cerebral vascular hypertrophy and vasomotor dysfunction in this model of dietary hyperhomocysteinemia. These findings provide insight into the mechanisms by which hyperhomocysteinemia promotes cerebral vascular disease and ischemic stroke.

Arctigenin improves vascular tone and decreases inflammation in human saphenous vein.

Science.gov (United States)

Daci, Armond; Neziri, Burim; Krasniqi, Shaip; Cavolli, Raif; Alaj, Rame; Norata, Giuseppe Danilo; Beretta, Giangiacomo

2017-09-05

The goal of this study was to test the effects of bioactive phenylpropanoid dibenzylbutyrolactone lignan arctigenin (ATG) in vascular tone. Human bypass graft vessel, from a saphenous vein (SV), were set up in organ bath system and contracted with potassium chloride (KCl, 40mM). Two concentration-response curves of noradrenaline (NE) (10nM-100μM) separated with an incubation period of 30min without (Control) or with ATG (3-100μM) were established. Inhibitors of nitric oxide, prostaglandins, K + related channels or calcium influx were used to delineate the molecular mechanisms beyond ATG effects. To investigate anti-inflammatory actions, SV were treated with 10μM or 100μM ATG and incubated for 18h in the absence or presence of both interleukin-1beta (IL-1β) and lipopolysaccharide (LPS) to mimic the physiological or inflamed tissue conditions. Proatherogenic and inflammatory mediators İnterleukine-1 beta (IL-1β), Monocyte Chemoattractant Proteine-1 (MCP-1), Tumor Necrosis Factor- α (TNF-α), İnterleukine-6 (IL-6), Prostaglandin E 2 (PGE 2 ) and İnterleukine-8 (IL-8) in the supernatant were measured. ATG significantly decreased vascular contractile response to NE. Moreover, it reduced contractions induced by KCl and cumulative addition of CaCl 2. The mediators were significantly increased in inflammatory conditions compared to normal conditions, an effect which was inhibited by ATG (10 and 100µM). ATG reduces contractions in SV and decreases the production of proinflammatory-proatherogenic mediators, setting the stage for further evaluating the effect of ATG in cardiovascular diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

Intrahepatic tissue pO2 during continuous or intermittent vascular inflow occlusion in a pig liver resection model

NARCIS (Netherlands)

van Wagensveld, B. A.; van Gulik, T. M.; Gabeler, E. E.; van der Kleij, A. J.; Obertop, H.; Gouma, D. J.

1998-01-01

BACKGROUND: Temporary vascular inflow occlusion of the liver (clamping of the hepatic pedicle) can prevent massive blood loss during liver resections. In this study, intrahepatic tissue pO2 was assessed as parameter of microcirculatory disturbances induced by ischemia and reperfusion (I/R) in the

Peritoneal Albumin and Protein Losses Do Not Predict Outcome in Peritoneal Dialysis Patients

NARCIS (Netherlands)

Balafa, Olga; Halbesma, Nynke; Struijk, Dirk G.; Dekker, Friedo W.; Krediet, Raymond T.

2011-01-01

Background and objectives Peritoneal clearance of albumin unlike the transport of small molecules is defined by both vascular surface area and size-selective permeability. Few studies have supported a positive correlation between peritoneal albumin loss and mortality. The aim of this study was to

Nilai Rerata Vascular Pedicle Width, Vascular Pedicle-Cardiac Ratio Vascular Pedicle-Thoracic Ratio Orang Dewasa Normal Indonesia Studi di RS dr. Cipto Mangunkusomo

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Rommy Zunera

2016-03-01

Full Text Available Vascular pedicle width (VPW adalah jarak tepi luar vena kava superior ke tepi luar arteri subklavia kiri. Pemeriksaan VPW di foto toraks bersifat non-invasif, cepat dan mudah untuk memprediksi hipervolemia.Penelitian ini bertujuan untuk mengetahui rerata nilai VPW orang dewasa normal Indonesia. VPW diukurdengan dua metode: pertama pengukuran VPW tunggal yang akurasinya terbatas di foto toraks digital karenarelatif tidak dipengaruhi faktor magnifikasi. Metode kedua untuk foto toraks nondigital yaitu pengukuranrasio:vascular pedicle-cardiac ratio (VPCR dan vascular pedicle-thoracic ratio (VPTR. Pengukuran serupadilakukan terhadap  topogram CT scan toraks AP terlentang dan CT scan toraks lalu dibandingkan akurasipengukuran di topogram dengan CT scan  toraks sebagai standar baku. Sampel terdiri atas 104 foto toraksPA subyek normal dan 103 CT scan  toraks subyek terpilih. Pada pemeriksaan toraks PA didapatkan rerata VPW 48,0±5,5mm, rerata VPCR 40,3±4,6%, dan rerata VPTR 17,2±1,7%. Pada pemeriksaan topogram CTscan didapatkan rerata VPW 50,3±6,2mm, rerata VPTR 45±5,1%, dan rerata VPTR 19,8±2,5%. Rerata VPWpada CT scan toraks 50,4±6,1mm. Pengukuran di foto toraks AP 10% lebih besar dibandingkan pada fototoraks PA dan pengukuranVPW di foto toraks terbukti memiliki akurasi  tinggi. Kata kunci: fototoraks, vascular pedicle width, vascular pedicle-cardiac ratio, vascular pedicle-thoracic ratio, hipervolemia.   The Mean Value of Vascular Pedicle Width, Vascular Pedicle-Cardiac Ratio,Vascular Pedicle-Thoracic Ratio of Normal Indonesian Adult Study In dr. Cipto Mangunkusomo Hospital Abstract Vascular pedicle width (VPW is the distance, from a perpendicular line at the takeoff point of the left subclavian artery off the aorta to the point at which the superior vena cava. Measurement of VPW on chestx-ray is relatively non-invasive, fast and easy technique as  hypervolemia predictor. The purpose of thisstudy is to know the mean VPW value of normal

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

Directory of Open Access Journals (Sweden)

Steenhof N

2014-06-01

Full Text Available Naomi Steenhof,1,2 Francesca Le Piane,1 Kori Leblanc,1–3 Naomi R Eisenberg,4 Yvonne Kwan,1 Christine Malmberg,1,6 Alexandra Papadopoulos,5,7 Graham Roche-Nagle4,7,8 1Department of Pharmacy, University Health Network, 2Leslie Dan Faculty of Pharmacy, University of Toronto, 3Centre for Innovation in Complex Care, University Health Network, 4Division of Vascular Surgery, University Health Network, 5Faculty of Nursing, University of Toronto, Toronto, ON, 6Victoria General Hospital, Vancouver Island Health Authority, Victoria, BC, 7Peter Munk Cardiac Centre, University Health Network, 8Faculty of Medicine, University of Toronto, Toronto, ON, Canada Background: Peripheral arterial disease (PAD guidelines recommend aggressive risk factor modification to improve cardiovascular outcomes. Recommended pharmacologic therapies include antiplatelets, angiotensin converting enzyme (ACE inhibitors, and HMG-CoA-reductase inhibitors (statins. Purpose: We studied the degree to which patient admission to a vascular surgery service increased the use of these therapies. Patients and methods: The authors conducted a retrospective chart review of 150 patients with PAD admitted to the vascular surgery service at a large Canadian tertiary care hospital. The use of recommended pharmacologic therapies at the time of admission and discharge were compared. A multidisciplinary clinical team established criteria by which patients were deemed ineligible to receive any of the recommended therapies. Angiotensin receptor blockers (ARBs were considered an alternative to ACE inhibitors. Results: Prior to hospital admission, 64% of patients were on antiplatelet therapy, 67% were on an ACE inhibitor or ARB, and 71% were on a statin. At the time of discharge, 91% of patients were on an antiplatelet (or not, with an acceptable reason, 77% were on an ACE inhibitor or an ARB (or not, with an acceptable reason, and 85% were on a statin (or not, with an acceptable reason. While new

Calcium dynamics in vascular smooth muscle

OpenAIRE

Amberg, Gregory C.; Navedo, Manuel F.

2013-01-01

Smooth muscle cells are ultimately responsible for determining vascular luminal diameter and blood flow. Dynamic changes in intracellular calcium are a critical mechanism regulating vascular smooth muscle contractility. Processes influencing intracellular calcium are therefore important regulators of vascular function with physiological and pathophysiological consequences. In this review we discuss the major dynamic calcium signals identified and characterized in vascular smooth muscle cells....

Noise-induced hearing loss in construction workers being assessed for hand-arm vibration syndrome.

Science.gov (United States)

House, Ronald A; Sauvé, John T; Jiang, Depeng

2010-01-01

Construction workers are at risk of noise-induced hearing loss (NIHL) but often have no periodic audiometric testing. The participants were construction workers assessed for Hand-Arm Vibration Syndrome (HAVS) at the Occupational Health Clinic, St. Michael's Hospital, Toronto, Ontario. Audiometry was offered and 169 of the 191 workers assessed for HAVS agreed to have the audiometric test. The objective was to examine the prevalence of hearing loss in these 169 workers and to determine the effect on hearing of duration of work in construction (as a proxy for noise exposure) and the severity of vibration white finger (VWF) which previous studies have suggested is a marker for increased individual susceptibility for NIHL. VWF was measured by the Stockholm vascular scale. All participants were men, median age of 57 (range: 28-75), median number of years worked in construction of 35 (range: 4-52). All of the Spearman rank correlations between years worked in construction and the hearing levels at each audiometric frequency were statistically significant (p hearing loss at or above the level at which a workers' compensation pension would be granted in Ontario and the prevalence of this auditory outcome had a statistically significant increase as years worked in construction increased. Multivariate linear regression indicated that VWF also had a statistically significant effect on hearing loss for all audiometric frequencies combined after controlling for years worked in construction. Improved prevention of hearing loss in construction workers is needed.

Cell sheet engineering using the stromal vascular fraction of adipose tissue as a vascularization strategy.

Science.gov (United States)

Costa, Marina; Cerqueira, Mariana T; Santos, Tírcia C; Sampaio-Marques, Belém; Ludovico, Paula; Marques, Alexandra P; Pirraco, Rogério P; Reis, Rui L

2017-06-01

Current vascularization strategies for Tissue Engineering constructs, in particular cell sheet-based, are limited by time-consuming and expensive endothelial cell isolation and/or by the complexity of using extrinsic growth factors. Herein, we propose an alternative strategy using angiogenic cell sheets (CS) obtained from the stromal vascular fraction (SVF) of adipose tissue that can be incorporated into more complex constructs. Cells from the SVF were cultured in normoxic and hypoxic conditions for up to 8days in the absence of extrinsic growth factors. Immunocytochemistry against CD31 and CD146 revealed spontaneous organization in capillary-like structures, more complex after hypoxic conditioning. Inhibition of HIF-1α pathway hindered capillary-like structure formation in SVF cells cultured in hypoxia, suggesting a role of HIF-1α. Moreover, hypoxic SVF cells showed a trend for increased secretion of angiogenic factors, which was reflected in increased network formation by endothelial cells cultured on matrigel using that conditioned medium. In vivo implantation of SVF CS in a mouse hind limb ischemia model revealed that hypoxia-conditioned CS led to improved restoration of blood flow. Both in vitro and in vivo data suggest that SVF CS can be used as simple and cost-efficient tools to promote functional vascularization of TE constructs. Neovascularization after implantation is a major obstacle for producing clinically viable cell sheet-based tissue engineered constructs. Strategies using endothelial cells and extrinsic angiogenic growth factors are expensive and time consuming and may raise concerns of tumorigenicity. In this manuscript, we describe a simplified approach using angiogenic cell sheets fabricated from the stromal vascular fraction of adipose tissue. The strong angiogenic behavior of these cell sheets, achieved without the use of external growth factors, was further stimulated by low oxygen culture. When implanted in an in vivo model of hind limb

Near-infrared spectroscopy for detection of vascular compromise in paediatric supracondylar fractures

International Nuclear Information System (INIS)

Skowno, Justin J; De Lima, Jonathan; Quick, Tom J; Carpenter, Eleanor C; Gibbons, Paul J; Little, David G

2014-01-01

Children suffering supracondylar fractures of the humerus are at risk of vascular compromise, which is currently assessed clinically, although other modalities such as angiography, pulse oximetry, Doppler ultrasound and magnetic resonance angiography have been used. We sought to ascertain whether tissue haemoglobin oxygenation (StO 2 ) measurement could distinguish between patients with and without clinical vascular compromise following supracondylar fractures of the humerus. We prospectively observed StO 2  using near-infrared spectroscopy in 29 paediatric patients with supracondylar fractures requiring operative manipulation. The injured and uninjured volar forearm compartments were monitored immediately before and after fracture reduction. The relationship between StO 2  in the injured and uninjured limb, and the presence of pre-operative vascular compromise was assessed. Seven out of 29 children presented with vascular compromise. Patients with clinical vascular compromise had significantly lower pre-reduction StO 2  (63.5% ± 15%, mean ± standard deviation), compared to those without compromise (80.9% ± 10%). StO 2  normalized following surgery in all children with vascular compromise. These improvements in muscle StO 2  were associated, in all patients, with the clinical return of pulses and resolution of neurological symptoms if present. StO 2  monitoring can identify patients with clinical vascular compromise, can identify the return of adequate perfusion following operative correction of supracondylar fractures, and may be a useful adjunct to clinical assessment. (paper)

Recent Advances in Cerebellar Ischemic Stroke Syndromes Causing Vertigo and Hearing Loss.

Science.gov (United States)

Kim, Hyun-Ah; Yi, Hyon-Ah; Lee, Hyung

2016-12-01

Cerebellar ischemic stroke is one of the common causes of vascular vertigo. It usually accompanies other neurological symptoms or signs, but a small infarct in the cerebellum can present with vertigo without other localizing symptoms. Approximately 11 % of the patients with isolated cerebellar infarction simulated acute peripheral vestibulopathy, and most patients had an infarct in the territory of the medial branch of the posterior inferior cerebellar artery (PICA). A head impulse test can differentiate acute isolated vertigo associated with PICA territory cerebellar infarction from more benign disorders involving the inner ear. Acute hearing loss (AHL) of a vascular cause is mostly associated with cerebellar infarction in the territory of the anterior inferior cerebellar artery (AICA), but PICA territory cerebellar infarction rarely causes AHL. To date, at least eight subgroups of AICA territory infarction have been identified according to the pattern of neurotological presentations, among which the most common pattern of audiovestibular dysfunction is the combined loss of auditory and vestibular functions. Sometimes acute isolated audiovestibular loss can be the initial symptom of impending posterior circulation ischemic stroke (particularly within the territory of the AICA). Audiovestibular loss from cerebellar infarction has a good long-term outcome than previously thought. Approximately half of patients with superior cerebellar artery territory (SCA) cerebellar infarction experienced true vertigo, suggesting that the vertigo and nystagmus in the SCA territory cerebellar infarctions are more common than previously thought. In this article, recent findings on clinical features of vertigo and hearing loss from cerebellar ischemic stroke syndrome are summarized.

Intermittent energy restriction improves weight loss efficiency in obese men: the MATADOR study

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Byrne, N M; Sainsbury, A; King, N A; Hills, A P; Wood, R E

2018-01-01

Background/Objectives: The MATADOR (Minimising Adaptive Thermogenesis And Deactivating Obesity Rebound) study examined whether intermittent energy restriction (ER) improved weight loss efficiency compared with continuous ER and, if so, whether intermittent ER attenuated compensatory responses associated with ER. Subjects/Methods: Fifty-one men with obesity were randomised to 16 weeks of either: (1) continuous (CON), or (2) intermittent (INT) ER completed as 8 × 2-week blocks of ER alternating with 7 × 2-week blocks of energy balance (30 weeks total). Forty-seven participants completed a 4-week baseline phase and commenced the intervention (CON: N=23, 39.4±6.8 years, 111.1±9.1 kg, 34.3±3.0 kg m−2; INT: N=24, 39.8±9.5 years, 110.2±13.8 kg, 34.1±4.0 kg m−2). During ER, energy intake was equivalent to 67% of weight maintenance requirements in both groups. Body weight, fat mass (FM), fat-free mass (FFM) and resting energy expenditure (REE) were measured throughout the study. Results: For the N=19 CON and N=17 INT who completed the intervention per protocol, weight loss was greater for INT (14.1±5.6 vs 9.1±2.9 kg; Penergy balance blocks was minimal (0.0±0.3 kg). While reduction in absolute REE did not differ between groups (INT: -502±481 vs CON: −624±557 kJ d−1; P=0.5), after adjusting for changes in body composition, it was significantly lower in INT (INT: −360±502 vs CON: −749±498 kJ d−1; Penergy balance ‘rest periods’ may reduce compensatory metabolic responses and, in turn, improve weight loss efficiency. PMID:28925405

Effectiveness of Vascular Markers (Immunohistochemical Stains) in Soft Tissue Sarcomas.

Science.gov (United States)

Naeem, Namra; Mushtaq, Sajid; Akhter, Noreen; Hussain, Mudassar; Hassan, Usman

2018-05-01

To ascertain the effectiveness of IHC markers of vascular origin like CD31, CD34, FLI1 and ERG in vascular soft tissue sarcomas including angiosarcomas, Kaposi sarcomas, epithelioid hemangioendothelioma and a non-vascular soft tissue sarcoma (Epithelioid sarcoma). Descriptive study. Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, from 2011 to 2017. Diagnosed cases of angiosarcomas (n=48), epithelioid hemangioendothelioma (n=9), Kaposi sarcoma (n=9) and epithelioid sarcoma (n=20) were selected. Immunohistochemical staining as performed on formalin fixed paraffin embedded sections. The sections were stained for the following markers: CD34 (VENTANA clone Q Bend 10), CD31 (Leica clone 1 A 10), FLI1 (CELL MARQUE clone MRQ-1) and ERG (CELL MARQUE clone EP111). A complete panel of CD34, CD31 and ERG was applied on 8/48 cases of angiosarcomas with triple positivity in 6 cases. Eight cases showed positivity for only CD31 and ERG and 2 cases showed positivity for only ERG. A complete panel of CD34, CD31 and ERG was applied on 3/9 cases of epithelioid hemangioendothelioma with positivity for all markers in 2 cases. Combined positivity for ERG and CD34 was seen in 2 cases and on 4 cases only CD31 immunohistochemical was solely applied with 100% positivity. FLI1 was not applied on any case. Among 9 cases of Kaposi sarcoma, ERG, CD34 and CD31 in combination were applied on only 1 case with triple positivity. Remaining cases show positivity for either CD34, CD31 or FLI1. Majority of cases of epithelioid sarcomas were diagnosed on the basis of cytokeratin and CD34 positivity with loss of INI1. The other vascular markers showed negativity in all cases. Among these four markers, ERG immunohistochemical stain is highly effective for endothelial differentiation due to its specific nuclear staining pattern in normal blood vessel endothelial cells (internal control) as well as neoplastic cells of vascular tumors and lack of background staining.

Towards retrievable vascularized bioartificial pancreas: induction and long-lasting stability of polymeric mesh implant vascularized with the help of acidic and basic fibroblast growth factors and hydrogel coating.

Science.gov (United States)

Prokop, A; Kozlov, E; Nun Non, S; Dikov, M M; Sephel, G C; Whitsitt, J S; Davidson, J M

2001-01-01

We seek to improve existing methodologies for allogenic grafting of pancreatic islets. The lack of success of encapsulated transplanted islets inside the peritoneal cavity is presently attributed to poor vascularization of the implant. A thick, fibrotic capsule often surrounds the graft, limiting survival. We have tested the hypothesis that neovascularization of the graft material can be induced by the addition of proper angiogenic factors embedded within a polymeric coat. Biocompatible and nonresorbable meshes coated with hydrophilic polymers were implanted in rats and harvested after 1-, 6-, and 12-week intervals. The implant response was assessed by histological observations on the degree of vascularity, fibrosis, and inflammation. Macrostructural geometry of meshes was conducive to tissue ingrowth into the interstitial space between the mesh filaments. Hydrogel coating with incorporated acidic or basic FGF in an electrostatic complex with polyelectrolytes and/or with heparin provided a sustained slow release of the angiogenic growth factor. Anti-factor VIII and anti-collagen type IV antibodies and a GSL I-B4 lectin were used to measure the extent of vascularization. Vigorous and persistent vascularization radiated several hundred microns from the implant. The level of vascularization should provide a sufficient diffusion of nutrients and oxygen to implanted islets. Based on our observations, stable vascularization may require a sustained angiogenic signal to allow for the development of a permanent implant structure.

Urea immunoliposome inhibits human vascular endothelial cell proliferation for hemangioma treatment

Science.gov (United States)

2013-01-01

Background Urea injection has been used in hemangioma treatment as sclerotherapy. It shrinks vascular endothelial cells and induces degeneration, necrosis, and fibrosis. However, this treatment still has disadvantages, such as lacking targeting and difficulty in controlling the urea dosage. Thus, we designed a urea immunoliposome to improve the efficiency of treatment. Methods The urea liposome was prepared by reverse phase evaporation. Furthermore, the urea immunoliposome was generated by coupling the urea liposome with a vascular endothelial growth factor receptor (VEGFR) monoclonal antibody using the glutaraldehyde cross-linking method. The influence of the urea immunoliposome on cultured human hemangioma vascular endothelial cells was observed preliminarily. Results Urea immunoliposomes showed typical liposome morphology under a transmission electron microscope, with an encapsulation percentage of 54.4% and a coupling rate of 36.84% for anti-VEGFR. Treatment with the urea immunoliposome significantly inhibited the proliferation of hemangioma vascular endothelial cells (HVECs) in a time- and dose-dependent manner. Conclusions The urea immunoliposome that we developed distinctly and persistently inhibited the proliferation of HVECs and is expected to be used in clinical hemangioma treatment. PMID:24266957

Effects of exercise training and resveratrol on vascular health in aging

DEFF Research Database (Denmark)

Gliemann, Lasse; Nyberg, Michael Permin; Hellsten, Ylva

2016-01-01

Cardiovascular disease is a leading cause of death in the western world with aging being one of the strongest predictors of cardiovascular events. Aging is associated with impaired vascular function due to endothelial dysfunction and altered redox balance, partly caused by an increased formation ...... effects of physical activity. Regular physical activity remains the most effective way of maintaining and improving vascular health status and caution should be taken regarding potential interference of supplements on training adaptations....... of the observed detrimental effects of aging on vascular function. The effects of aging and physical activity on vascular function are, in part, related to alterations in cellular signaling through sirtuin-1, AMPK and the estrogen receptor. The polyphenol resveratrol can activate these same pathways and has......, in animals and in vitro models, been shown to act as a partial mimetic of physical activity. However, support for beneficial effects of resveratrol in human is weak and studies even show that resveratrol supplementation, similarly to supplementation with other antioxidants, can counteract the positive...

PanVascular medicine. 2. ed.

Energy Technology Data Exchange (ETDEWEB)

Lanzer, Peter (ed.) [Health Care Center Bitterfeld (Germany). Division of Cardiovascular Disease

2015-06-01

Vascular management and care has become a truly multidisciplinary enterprise as the number of specialists involved in the treatment of patients with vascular diseases has steadily increased. While in the past, treatments were delivered by individual specialists, in the twenty-first century a team approach is without doubt the most effective strategy. In order to promote professional excellence in this dynamic and rapidly evolving field, a shared knowledge base and interdisciplinary standards need to be established. Pan Vascular Medicine, 2nd edition has been designed to offer such an interdisciplinary platform, providing vascular specialists with state-of-the art descriptive and procedural knowledge. Basic science, diagnostics, and therapy are all comprehensively covered. In a series of succinct, clearly written chapters, renowned specialists introduce and comment on the current international guidelines and present up-to-date reviews of all aspects of vascular care.

PanVascular medicine. 2. ed.

International Nuclear Information System (INIS)

Lanzer, Peter

2015-01-01

Vascular management and care has become a truly multidisciplinary enterprise as the number of specialists involved in the treatment of patients with vascular diseases has steadily increased. While in the past, treatments were delivered by individual specialists, in the twenty-first century a team approach is without doubt the most effective strategy. In order to promote professional excellence in this dynamic and rapidly evolving field, a shared knowledge base and interdisciplinary standards need to be established. Pan Vascular Medicine, 2nd edition has been designed to offer such an interdisciplinary platform, providing vascular specialists with state-of-the art descriptive and procedural knowledge. Basic science, diagnostics, and therapy are all comprehensively covered. In a series of succinct, clearly written chapters, renowned specialists introduce and comment on the current international guidelines and present up-to-date reviews of all aspects of vascular care.

[The age-related macular degeneration as a vascular disease/part of systemic vasculopathy: contributions to its pathogenesis].

Science.gov (United States)

Fischer, Tamás

2015-03-01

The wall of blood vessels including those in choroids may be harmed by several repeated and/or prolonged mechanical, physical, chemical, microbiological, immunologic, and genetic impacts (risk factors), which may trigger a protracted response, the so-called host defense response. As a consequence, pathological changes resulting in vascular injury (e. g. atherosclerosis, age-related macular degeneration) may be evolved. Risk factors can also act directly on the endothelium through an increased production of reactive oxygen species promoting an endothelial activation, which leads to endothelial dysfunction, the onset of vascular disease. Thus, endothelial dysfunction is a link between the harmful stimulus and vascular injury; any kind of harmful stimuli may trigger the defensive chain that results in inflammation that may lead to vascular injury. It has been shown that even early age-related macular degeneration is associated with the presence of diffuse arterial disease and patients with early age-related macular degeneration demonstrate signs of systemic and retinal vascular alterations. Chronic inflammation, a feature of AMD, is tightly linked to diseases associated with ED: AMD is accompanied by a general inflammatory response, in the form of complement system activation, similar to that observed in degenerative vascular diseases such as atherosclerosis. All these facts indicate that age-related macular degeneration may be a vascular disease (or part of a systemic vasculopathy). This recognition could have therapeutic implications because restoration of endothelial dysfunction may prevent the development or improve vascular disease resulting in prevention or improvement of age-related macular degeneration as well.

[The future of vascular medicine].

Science.gov (United States)

Kroeger, K; Luther, B

2014-10-01

In the future vascular medicine will still have a great impact on health of people. It should be noted that the aging of the population does not lead to a dramatic increase in patient numbers, but will be associated with a changing spectrum of co-morbidities. In addition, vascular medical research has to include the intensive care special features of vascular patients, the involvement of vascular medicine in a holistic concept of fast-track surgery, a geriatric-oriented intensive monitoring and early geriatric rehabilitation. For the future acceptance of vascular medicine as a separate subject area under delimitation of cardiology and radiology is important. On the other hand, the subject is so complex and will become more complex in future specialisations that mixing of surgery and angiology is desirable, with the aim to preserve the vascular surgical knowledge and skills on par with the medical and interventional measures and further develop them. Only large, interdisciplinary guided vascular centres will be able to provide timely diagnosis and therapy, to deal with the growing multi-morbidity of the patient, to perform complex therapies even in an acute emergency and due to sufficient number of cases to present with well-trained and experienced teams. These requirements are mandatory to decrease patients' mortality step by step. Georg Thieme Verlag KG Stuttgart · New York.

Composite vascular repair grafts via micro-imprinting and electrospinning

Energy Technology Data Exchange (ETDEWEB)

Liu, Yuanyuan, E-mail: yuanyuan-liu@shu.edu.cn; Hu, Qingxi, E-mail: huqingxi@shu.edu.cn [Rapid Manufacturing Engineering Center, Shanghai University, Shanghai 200444 (China); Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai 200072 (China); Xiang, Ke, E-mail: xiangke@shu.edu.cn; Chen, Haiping, E-mail: 519673062@qq.com; Li, Yu, E-mail: liyu@hpu.edu.cn [Rapid Manufacturing Engineering Center, Shanghai University, Shanghai 200444 (China)

2015-04-15

Composite vascular grafts formed by micro-imprinting and electrospinning exhibited improved mechanical properties relative to those formed by electrospinning alone. The three-layered composite grafts mimic the three-layered structure of natural blood vessels. The middle layer is made by micro-imprinting poly-p-dioxanone (PPDO), while the inner and outer layers are electrospun mixtures of chitosan and polyvinyl alcohol. The graft morphology is characterized with scanning electron microscopy. For constant graft thicknesses, the PPDO increases the mechanical strength. Cells cultivated on the vascular grafts adhere and proliferate better because of the natural, biological chitosan in the inner and outer layers. Overall, the composite scaffolds could be good candidates for blood vessel repair.

Benign vascular lesions of bone: radiologic and pathologic features

Energy Technology Data Exchange (ETDEWEB)

Wenger, D.E.; Wold, L.E. [Mayo Foundation, Rochester, MN (United States)

2000-02-01

The benign vascular tumors of bone represent a diverse group of tumors that can present with a broad spectrum of clinical signs and symptoms. They can also present a significant diagnostic challenge due to their widely variable radiographic imaging and histologic features. Some of the tumors manifest as clearly benign lesions with tissue-specific diagnostic imaging features, while others have non-specific imaging features that may simulate malignant neoplasm. This article will provide a review of the nomenclature and the characteristic radiographic and pathologic features of the benign vascular lesions of bone. The information will aid in improving our diagnostic accuracy and enhance our understanding of the biologic potential of this diverse group of osseous lesions. (orig.)

Benign vascular lesions of bone: radiologic and pathologic features

International Nuclear Information System (INIS)

Wenger, D.E.; Wold, L.E.

2000-01-01

The benign vascular tumors of bone represent a diverse group of tumors that can present with a broad spectrum of clinical signs and symptoms. They can also present a significant diagnostic challenge due to their widely variable radiographic imaging and histologic features. Some of the tumors manifest as clearly benign lesions with tissue-specific diagnostic imaging features, while others have non-specific imaging features that may simulate malignant neoplasm. This article will provide a review of the nomenclature and the characteristic radiographic and pathologic features of the benign vascular lesions of bone. The information will aid in improving our diagnostic accuracy and enhance our understanding of the biologic potential of this diverse group of osseous lesions. (orig.)

Vascular neurocognitive disorders and the vascular risk factors

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Carmen V. Albu

2018-04-01

Full Text Available Dementias are clinical neurodegenerative diseases characterized by permanent and progressive transformation of cognitive functions such as memory, learning capacity, attention, thinking, language, passing judgments, calculation or orientation. Dementias represent a relatively frequent pathology, encountered at about 10% of the population of 65-year olds and 20% of the population of 80-year olds. This review presents the main etiological forms of dementia, which include Alzheimer form of dementia, vascular dementia, dementia associated with alpha-synucleionopathies, and mixed forms. Regarding vascular dementia, the risk factors are similar to those for an ischemic or hemorrhagic cerebrovascular accident: arterial hypertension, diabetes mellitus, dyslipidemia, smoking, obesity, age, alcohol consumption, cerebral atherosclerosis/ arteriosclerosis. Several studies show that efficient management of the vascular risk factors can prevent the expression and/ or progression of dementia. Thus, lifestyle changes such as stress reduction, regular physical exercise, decreasing dietary fat, multivitamin supplementation, adequate control of blood pressure and serum cholesterol, and social integration and mental stimulation in the elderly population are important factors in preventing or limiting the symptoms of dementia, a disease with significant individual, social, and economic implications.

Frailty assessment in vascular surgery and its utility in preoperative decision making.

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Kraiss, Larry W; Beckstrom, Julie L; Brooke, Benjamin S

2015-06-01

The average patient requiring vascular surgery has become older, as life expectancy within the US population has increased. Many older patients have some degree of frailty and reside near the limit of their physiological reserve with restricted ability to respond to stressors such as surgery. Frailty assessment is an important part of the preoperative decision-making process, in order to determine whether patients are fit enough to survive the vascular surgery procedure and live long enough to benefit from the intervention. In this review, we will discuss different measures of frailty assessment and how they can be used by vascular surgery providers to improve preoperative decision making and the quality of patient care. Copyright © 2015 Elsevier Inc. All rights reserved.

Dietary restriction but not angiotensin II type 1 receptor blockade improves DNA damage-related vasodilator dysfunction in rapidly aging Ercc1Δ/- mice.

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Wu, Haiyan; van Thiel, Bibi S; Bautista-Niño, Paula K; Reiling, Erwin; Durik, Matej; Leijten, Frank P J; Ridwan, Yanto; Brandt, Renata M C; van Steeg, Harry; Dollé, Martijn E T; Vermeij, Wilbert P; Hoeijmakers, Jan H J; Essers, Jeroen; van der Pluijm, Ingrid; Danser, A H Jan; Roks, Anton J M

2017-08-01

DNA damage is an important contributor to endothelial dysfunction and age-related vascular disease. Recently, we demonstrated in a DNA repair-deficient, prematurely aging mouse model ( Ercc1 Δ/- mice) that dietary restriction (DR) strongly increases life- and health span, including ameliorating endothelial dysfunction, by preserving genomic integrity. In this mouse mutant displaying prominent accelerated, age-dependent endothelial dysfunction we investigated the signaling pathways involved in improved endothelium-mediated vasodilation by DR, and explore the potential role of the renin-angiotensin system (RAS). Ercc1 Δ/- mice showed increased blood pressure and decreased aortic relaxations to acetylcholine (ACh) in organ bath experiments. Nitric oxide (NO) signaling and phospho-Ser 1177 -eNOS were compromised in Ercc1 Δ / - DR improved relaxations by increasing prostaglandin-mediated responses. Increase of cyclo-oxygenase 2 and decrease of phosphodiesterase 4B were identified as potential mechanisms. DR also prevented loss of NO signaling in vascular smooth muscle cells and normalized angiotensin II (Ang II) vasoconstrictions, which were increased in Ercc1 Δ/- mice. Ercc1 Δ/ - mutants showed a loss of Ang II type 2 receptor-mediated counter-regulation of Ang II type 1 receptor-induced vasoconstrictions. Chronic losartan treatment effectively decreased blood pressure, but did not improve endothelium-dependent relaxations. This result might relate to the aging-associated loss of treatment efficacy of RAS blockade with respect to endothelial function improvement. In summary, DR effectively prevents endothelium-dependent vasodilator dysfunction by augmenting prostaglandin-mediated responses, whereas chronic Ang II type 1 receptor blockade is ineffective. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

[Experimental study of angiography using vascular interventional robot-2(VIR-2)].

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Tian, Zeng-min; Lu, Wang-sheng; Liu, Da; Wang, Da-ming; Guo, Shu-xiang; Xu, Wu-yi; Jia, Bo; Zhao, De-peng; Liu, Bo; Gao, Bao-feng

2012-06-01

To verify the feasibility and safety of new vascular interventional robot system used in vascular interventional procedures. Vascular interventional robot type-2 (VIR-2) included master-slave parts of body propulsion system, image navigation systems and force feedback system, the catheter movement could achieve under automatic control and navigation, force feedback was integrated real-time, followed by in vitro pre-test in vascular model and cerebral angiography in dog. Surgeon controlled vascular interventional robot remotely, the catheter was inserted into the intended target, the catheter positioning error and the operation time would be evaluated. In vitro pre-test and animal experiment went well; the catheter can enter any branch of vascular. Catheter positioning error was less than 1 mm. The angiography operation in animal was carried out smoothly without complication; the success rate of the operation was 100% and the entire experiment took 26 and 30 minutes, efficiency was slightly improved compared with the VIR-1, and the time what staff exposed to the DSA machine was 0 minute. The resistance of force sensor can be displayed to the operator to provide a security guarantee for the operation. No surgical complications. VIR-2 is safe and feasible, and can achieve the catheter remote operation and angiography; the master-slave system meets the characteristics of traditional procedure. The three-dimensional image can guide the operation more smoothly; force feedback device provides remote real-time haptic information to provide security for the operation.

Improvement in transmission loss of aircraft double wall with resonators

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Sun, Jincai; Shi, Liming; Ye, Xining

1991-08-01

A little volume low frequency resonator applicable to double-wall configuration of propeller-driven aircraft was designed on the basis of the principle of Helmholtz resonator. The normal incidence absorption coefficient of the various single resonator has been measured. The agreement between theoretical and experimental results is encouraging. An array of resonators whose resonant frequency at 85 Hz and 160 Hz, respectively, are installed between aircraft double-panel, and it has been shown that transmission loss of the double wall structure with resonators improve 4 dB and 6.5 dB in 1/3rd octave bandwidth at 80 Hz and 160 Hz center frequency, respectively, and 5 dB and 7 dB at resonant frequencies, compared with that of the double wall configuration without resonators.

Impaired vascular function in physically active premenopausal women with functional hypothalamic amenorrhea is associated with low shear stress and increased vascular tone.

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O'Donnell, Emma; Goodman, Jack M; Mak, Susanna; Harvey, Paula J

2014-05-01

Exercise-trained hypoestrogenic premenopausal women with functional hypothalamic amenorrhea (ExFHA) exhibit impaired endothelial function. The vascular effects of an acute bout of exercise, a potent nitric oxide stimulus, in these women are unknown. Three groups were studied: recreationally active ExFHA women (n = 12; 24.2 ± 1.2 years of age; mean ± SEM), and recreationally active (ExOv; n = 14; 23.5 ± 1.2 years of age) and sedentary (SedOv; n = 15; 23.1 ± 0.5 years of age) ovulatory eumenorrheic women. Calf blood flow (CBF) and brachial artery flow-mediated dilation (FMD) were evaluated using plethysmographic and ultrasound techniques, respectively, both before and 1 hour after 45 minutes of moderate-intensity exercise. Endothelium-independent dilation was assessed at baseline using glyceryl trinitrate. Calf vascular resistance (CVR) and brachial peak shear rate, as determined by the area under the curve (SRAUCpk), were also calculated. FMD and glyceryl trinitrate responses were lower (P .05) the findings. CBF was lower (P .05) between the groups. CBF in ExFHA was increased (P < .05) and CVR decreased (P < .05) to levels observed in ovulatory women. Acute dynamic exercise improves vascular function in ExFHA women. Although the role of estrogen deficiency per se is unclear, our findings suggest that low shear rate and increased vasoconstrictor tone may play a role in impaired basal vascular function in these women.

High-Protein Intake during Weight Loss Therapy Eliminates the Weight-Loss-Induced Improvement in Insulin Action in Obese Postmenopausal Women

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Gordon I. Smith

2016-10-01

Full Text Available High-protein (HP intake during weight loss (WL therapy is often recommended because it reduces the loss of lean tissue mass. However, HP intake could have adverse effects on metabolic function, because protein ingestion reduces postprandial insulin sensitivity. In this study, we compared the effects of ∼10% WL with a hypocaloric diet containing 0.8 g protein/kg/day and a hypocaloric diet containing 1.2 g protein/kg/day on muscle insulin action in postmenopausal women with obesity. We found that HP intake reduced the WL-induced decline in lean tissue mass by ∼45%. However, HP intake also prevented the WL-induced improvements in muscle insulin signaling and insulin-stimulated glucose uptake, as well as the WL-induced adaptations in oxidative stress and cell structural biology pathways. Our data demonstrate that the protein content of a WL diet can have profound effects on metabolic function and underscore the importance of considering dietary macronutrient composition during WL therapy for people with obesity.

Cytomegalovirus (CMV) Infection Causes Degeneration of Cochlear Vasculature and Hearing Loss in a Mouse Model.

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Carraro, Mattia; Almishaal, Ali; Hillas, Elaine; Firpo, Matthew; Park, Albert; Harrison, Robert V

2017-04-01

Cytomegalovirus (CMV) infection is one of the most common causes of congenital hearing loss in children. We have used a murine model of CMV infection to reveal functional and structural cochlear pathogenesis. The cerebral cortex of Balb/c mice (Mus musculus) was inoculated with 2000 pfu (plaque forming units) of murine CMV on postnatal day 3. At 6 weeks of age, cochlear function was monitored using auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) measures. Histological assessment of cochlear vasculature using a corrosion cast technique was made at 8 weeks. Vascular casts of mCMV-damaged cochleas, and those of untreated control animals, were examined using scanning electron microscopy. We find very large variations in the degree of vascular damage in animals given identical viral injections (2000 pfu). The primary lesion caused by CMV infection is to the stria vascularis and to the adjacent spiral limbus capillary network. Capillary beds of the spiral ligament are generally less affected. The initial vascular damage is found in the mid-apical turn and appears to progress to more basal cochlear regions. After viral migration to the inner ear, the stria vascularis is the primary affected structure. We suggest that initial auditory threshold losses may relate to the poor development or maintenance of the endocochlear potential caused by strial dysfunction. Our increased understanding of the pathogenesis of CMV-related hearing loss is important for defining methods for early detection and treatment.

Synergistic actions of hematopoietic and mesenchymal stem/progenitor cells in vascularizing bioengineered tissues.

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Eduardo K Moioli

Full Text Available Poor angiogenesis is a major road block for tissue repair. The regeneration of virtually all tissues is limited by angiogenesis, given the diffusion of nutrients, oxygen, and waste products is limited to a few hundred micrometers. We postulated that co-transplantation of hematopoietic and mesenchymal stem/progenitor cells improves angiogenesis of tissue repair and hence the outcome of regeneration. In this study, we tested this hypothesis by using bone as a model whose regeneration is impaired unless it is vascularized. Hematopoietic stem/progenitor cells (HSCs and mesenchymal stem/progenitor cells (MSCs were isolated from each of three healthy human bone marrow samples and reconstituted in a porous scaffold. MSCs were seeded in micropores of 3D calcium phosphate (CP scaffolds, followed by infusion of gel-suspended CD34(+ hematopoietic cells. Co-transplantation of CD34(+ HSCs and CD34(- MSCs in microporous CP scaffolds subcutaneously in the dorsum of immunocompromised mice yielded vascularized tissue. The average vascular number of co-transplanted CD34(+ and MSC scaffolds was substantially greater than MSC transplantation alone. Human osteocalcin was expressed in the micropores of CP scaffolds and was significantly increased upon co-transplantation of MSCs and CD34(+ cells. Human nuclear staining revealed the engraftment of transplanted human cells in vascular endothelium upon co-transplantation of MSCs and CD34(+ cells. Based on additional in vitro results of endothelial differentiation of CD34(+ cells by vascular endothelial growth factor (VEGF, we adsorbed VEGF with co-transplanted CD34(+ and MSCs in the microporous CP scaffolds in vivo, and discovered that vascular number and diameter further increased, likely owing to the promotion of endothelial differentiation of CD34(+ cells by VEGF. Together, co-transplantation of hematopoietic and mesenchymal stem/progenitor cells may improve the regeneration of vascular dependent tissues such as bone

Acceleration of vascularized bone tissue-engineered constructs in a large animal model combining intrinsic and extrinsic vascularization.

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Weigand, Annika; Beier, Justus P; Hess, Andreas; Gerber, Thomas; Arkudas, Andreas; Horch, Raymund E; Boos, Anja M

2015-05-01

During the last decades, a range of excellent and promising strategies in Bone Tissue Engineering have been developed. However, the remaining major problem is the lack of vascularization. In this study, extrinsic and intrinsic vascularization strategies were combined for acceleration of vascularization. For optimal biomechanical stability of the defect site and simplifying future transition into clinical application, a primary stable and approved nanostructured bone substitute in clinically relevant size was used. An arteriovenous (AV) loop was microsurgically created in sheep and implanted, together with the bone substitute, in either perforated titanium chambers (intrinsic/extrinsic) for different time intervals of up to 18 weeks or isolated Teflon(®) chambers (intrinsic) for 18 weeks. Over time, magnetic resonance imaging and micro-computed tomography (CT) analyses illustrate the dense vascularization arising from the AV loop. The bone substitute was completely interspersed with newly formed tissue after 12 weeks of intrinsic/extrinsic vascularization and after 18 weeks of intrinsic/extrinsic and intrinsic vascularization. Successful matrix change from an inorganic to an organic scaffold could be demonstrated in vascularized areas with scanning electron microscopy and energy dispersive X-ray spectroscopy. Using the intrinsic vascularization method only, the degradation of the scaffold and osteoclastic activity was significantly lower after 18 weeks, compared with 12 and 18 weeks in the combined intrinsic-extrinsic model. Immunohistochemical staining revealed an increase in bone tissue formation over time, without a difference between intrinsic/extrinsic and intrinsic vascularization after 18 weeks. This study presents the combination of extrinsic and intrinsic vascularization strategies for the generation of an axially vascularized bone substitute in clinically relevant size using a large animal model. The additional extrinsic vascularization promotes tissue

Social media in vascular surgery.

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Indes, Jeffrey E; Gates, Lindsay; Mitchell, Erica L; Muhs, Bart E

2013-04-01

There has been a tremendous growth in the use of social media to expand the visibility of various specialties in medicine. The purpose of this paper is to describe the latest updates on some current applications of social media in the practice of vascular surgery as well as existing limitations of use. This investigation demonstrates that the use of social networking sites appears to have a positive impact on vascular practice, as is evident through the incorporation of this technology at the Cleveland Clinic and by the Society for Vascular Surgery into their approach to patient care and physician communication. Overall, integration of social networking technology has current and future potential to be used to promote goals, patient awareness, recruitment for clinical trials, and professionalism within the specialty of vascular surgery. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Proven Weight Loss Methods

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Fact Sheet Proven Weight Loss Methods What can weight loss do for you? Losing weight can improve your health in a number of ways. It can lower ... at www.hormone.org/Spanish . Proven Weight Loss Methods Fact Sheet www.hormone.org

Vascular elastic photoacoustic tomography in humans

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Hai, Pengfei; Zhou, Yong; Liang, Jinyang; Li, Chiye; Wang, Lihong V.

2016-03-01

Quantification of vascular elasticity can help detect thrombosis and prevent life-threatening conditions such as acute myocardial infarction or stroke. Here, we propose vascular elastic photoacoustic tomography (VE-PAT) to measure vascular elasticity in humans. VE-PAT was developed by incorporating a linear-array-based photoacoustic computed tomography system with a customized compression stage. By measuring the deformation of blood vessels under uniaxial loading, VE-PAT was able to quantify the vascular compliance. We first demonstrated the feasibility of VE-PAT in blood vessel phantoms. In large vessel phantoms, VE-PAT detected a decrease in vascular compliance due to simulated thrombosis, which was validated by a standard compression test. In small blood vessel phantoms embedded 3 mm deep in gelatin, VE-PAT detected elasticity changes at depths that are difficult to image using other elasticity imaging techniques. We then applied VE-PAT to assess vascular compliance in a human subject and detected a decrease in vascular compliance when an occlusion occurred downstream from the measurement point, demonstrating the potential of VE-PAT in clinical applications such as detection of deep venous thrombosis.

Diagnosis and management of vascular diseases

International Nuclear Information System (INIS)

Fan Xindong; Zheng Lianzhou

2011-01-01

Vascular disorders mainly include hemangiomas and vascular malformations, and constitute some of the most difficult diagnostic and therapeutic enigmas that can be encountered in the clinical practice. The clinical presentations are extremely variable and can range from an asymptomatic birthmark to life-threatening congestive heart failure. Attributing any of these extremely varied symptoms that a patients may present with to a vascular malformation may be a challenge to the most experienced clinical. This problem is compounded by the extreme rarity of these vascular lesions. If a clinician meets such a patient once every few years, it will be extremely difficult for the physicians to gain a steep learning curve. In such circumstances, it is difficult to formulate a standard of diagnosis and treatment for these vascular disorders. This paper aims to make a comprehensive and detailed description of the classification and diagnosis of the vascular disorders, the common used embolization agents, the concepts of interventional diagnosis and management and the therapies of various hemangiomas and vascular malformations. (authors)

Loss of function mutations in EPHB4 are responsible for vein of Galen aneurysmal malformation.

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Vivanti, Alexandre; Ozanne, Augustin; Grondin, Cynthia; Saliou, Guillaume; Quevarec, Loic; Maurey, Helène; Aubourg, Patrick; Benachi, Alexandra; Gut, Marta; Gut, Ivo; Martinovic, Jelena; Sénat, Marie Victoire; Tawk, Marcel; Melki, Judith

2018-04-01

See Meschia (doi:10.1093/brain/awy066) for a scientific commentary on this article.Vein of Galen aneurysmal malformation is a congenital anomaly of the cerebral vasculature representing 30% of all paediatric vascular malformations. We conducted whole exome sequencing in 19 unrelated patients presenting this malformation and subsequently screened candidate genes in a cohort of 32 additional patients using either targeted exome or Sanger sequencing. In a cohort of 51 patients, we found five affected individuals with heterozygous mutations in EPHB4 including de novo frameshift (p.His191Alafs*32) or inherited deleterious splice or missense mutations predicted to be pathogenic by in silico tools. Knockdown of ephb4 in zebrafish embryos leads to specific anomalies of dorsal cranial vessels including the dorsal longitudinal vein, which is the orthologue of the median prosencephalic vein and the embryonic precursor of the vein of Galen. This model allowed us to investigate EPHB4 loss-of-function mutations in this disease by the ability to rescue the brain vascular defect in knockdown zebrafish co-injected with wild-type, but not truncated EPHB4, mimicking the p.His191Alafs mutation. Our data showed that in both species, loss of function mutations of EPHB4 result in specific and similar brain vascular development anomalies. Recently, EPHB4 germline mutations have been reported in non-immune hydrops fetalis and in cutaneous capillary malformation-arteriovenous malformation. Here, we show that EPHB4 mutations are also responsible for vein of Galen aneurysmal malformation, indicating that heterozygous germline mutations of EPHB4 result in a large clinical spectrum. The identification of EPHB4 pathogenic mutations in patients presenting capillary malformation or vein of Galen aneurysmal malformation should lead to careful follow-up of pregnancy of carriers for early detection of anomaly of the cerebral vasculature in order to propose optimal neonatal care. Endovascular

Atherectomy-Associated Complications in the Southern California Vascular Outcomes Improvement Collaborative.

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Azar, Yara; DeRubertis, Brian; Baril, Donald; Woo, Karen

2018-05-01

Atherectomy has become an increasingly utilized modality for the endovascular treatment of peripheral arterial occlusive disease. The objective of this study was to determine the incidence and risk factors for atherectomy-associated complications. A retrospective review was performed for all atherectomy procedures performed between January 2011 and December 2015 in the Southern California Vascular Outcomes Improvement Collaborative. Atherectomy was defined as laser, orbital, or excisional atherectomy. Complications were dissection, perforation, and distal embolization. Seven hundred twenty-nine atherectomy procedures were performed at 7 institutions by 27 practitioners. The mean age was 73 years with 415 (57%) males. Four hundred nineteen (57%) were diabetic, 673 (92%) hypertensive, 457 (63%) smokers, and 244 (34%) had coronary artery disease. Dissection occurred in 51 (7%) procedures, embolization in 23 (3.1%), and perforation in 12 (1.6%). The mean number of lesions treated per artery was the same at 1.6 in patients with any complication and no complication (P = 0.77). The total occluded length was 7.4 cm for complications versus 7.2 cm for no complication (P = 0.73). The total treated length was 12.9 cm for complications versus 11.3 cm for no complication (P = 0.03). The incidence of complications for Trans-Atlantic Inter-Society Consensus (TASC) C/D lesions were 13% compared to 10% for TASC A/B lesions (P = 0.05). The incidence of complications in superficial femoral/popliteal lesions was 12.9% vs. 10.4% in tibial lesions (P = 0.13). In multivariable analysis, treatment length was associated with a small increased risk of complication (odds ratio = 1.02, 95% confidence interval = 1.0-1.04). Increased treatment length is associated with an increased risk of atherectomy-associated complications. Demographic factors and comorbidities were not predictors of complications. Copyright © 2017 Elsevier Inc. All rights reserved.

Human cord blood progenitors with high aldehyde dehydrogenase activity improve vascular density in a model of acute myocardial infarction

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Creer Michael H

2010-03-01

Full Text Available Abstract Human stem cells from adult sources have been shown to contribute to the regeneration of muscle, liver, heart, and vasculature. The mechanisms by which this is accomplished are, however, still not well understood. We tested the engraftment and regenerative potential of human umbilical cord blood-derived ALDHhiLin-, and ALDHloLin- cells following transplantation to NOD/SCID or NOD/SCID β2m null mice with experimentally induced acute myocardial infarction. We used combined nanoparticle labeling and whole organ fluorescent imaging to detect human cells in multiple organs 48 hours post transplantation. Engraftment and regenerative effects of cell treatment were assessed four weeks post transplantation. We found that ALDHhiLin- stem cells specifically located to the site of injury 48 hours post transplantation and engrafted the infarcted heart at higher frequencies than ALDHloLin- committed progenitor cells four weeks post transplantation. We found no donor derived cardiomyocytes and few endothelial cells of donor origin. Cell treatment was not associated with any detectable functional improvement at the four week endpoint. There was, however, a significant increase in vascular density in the central infarct zone of ALDHhiLin- cell-treated mice, as compared to PBS and ALDHloLin- cell-treated mice. Conclusions Our data indicate that adult human stem cells do not become a significant part of the regenerating tissue, but rapidly home to and persist only temporarily at the site of hypoxic injury to exert trophic effects on tissue repair thereby enhancing vascular recovery.

Tools for evidence-based vascular nursing practice: Achieving information literacy for lifelong learning.

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Jameson, Jodi; Walsh, M Eileen

2017-12-01

Information literacy is essential in facilitating evidence-based practice (EBP) activities. In vascular nursing, the implementation of EBP is of utmost importance. Best practice grounded in research evidence can contribute to improved patient care outcomes for individuals with vascular disease. The following paper discusses information literacy competencies for nurses to develop in the context of EBP, with an emphasis on formulating a clinical question and searching for evidence. Relevant health science information resources are described, including their value and purpose in the 6S model of evidence. Also discussed are practical and supportive solutions with proven effectiveness in ensuring nurses' success with EBP. Copyright © 2017 Society for Vascular Nursing, Inc. Published by Elsevier Inc. All rights reserved.

Vascular disease in cocaine addiction.

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Bachi, Keren; Mani, Venkatesh; Jeyachandran, Devi; Fayad, Zahi A; Goldstein, Rita Z; Alia-Klein, Nelly

2017-07-01

Cocaine, a powerful vasoconstrictor, induces immune responses including cytokine elevations. Chronic cocaine use is associated with functional brain impairments potentially mediated by vascular pathology. Although the Crack-Cocaine epidemic has declined, its vascular consequences are increasingly becoming evident among individuals with cocaine use disorder of that period, now aging. Paradoxically, during the period when prevention efforts could make a difference, this population receives psychosocial treatment at best. We review major postmortem and in vitro studies documenting cocaine-induced vascular toxicity. PubMed and Academic Search Complete were used with relevant terms. Findings consist of the major mechanisms of cocaine-induced vasoconstriction, endothelial dysfunction, and accelerated atherosclerosis, emphasizing acute, chronic, and secondary effects of cocaine. The etiology underlying cocaine's acute and chronic vascular effects is multifactorial, spanning hypertension, impaired homeostasis and platelet function, thrombosis, thromboembolism, and alterations in blood flow. Early detection of vascular disease in cocaine addiction by multimodality imaging is discussed. Treatment may be similar to indications in patients with traditional risk-factors, with few exceptions such as enhanced supportive care and use of benzodiazepines and phentolamine for sedation, and avoiding β-blockers. Given the vascular toxicity cocaine induces, further compounded by smoking and alcohol comorbidity, and interacting with aging of the crack generation, there is a public health imperative to identify pre-symptomatic markers of vascular impairments in cocaine addiction and employ preventive treatment to reduce silent disease progression. Copyright © 2017 Elsevier B.V. All rights reserved.

The vascular pattern in the flower of some Mesembryanthemaceae: Aptenia cordifolia and Dorotheanthus bellidiformis. The effect of an ontogenetical shifting on the vascular pattern and vascular conservatism

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Meulen-Bruijns, van der C.

1976-01-01

1. The vascular pattern in the flower at various stages of maturity of Aptenia cordifolia and Dorotheanthus bellidiformis is examined. 2. The vascular pattern of Dorotheanthus has been compared with that of Aptenia: typologically, Dorotheanthus is derived from Aptenia. 3. The vascular pattern of

Aerobic exercise training does not alter vascular structure and function in chronic obstructive pulmonary disease.

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Gelinas, Jinelle C; Lewis, Nia C; Harper, Megan I; Melzer, Bernie; Agar, Gloria; Rolf, J Douglass; Eves, Neil D

2017-11-01

What is the central question of this study? Chronic obstructive pulmonary disease (COPD) is associated with endothelial dysfunction, arterial stiffness and systemic inflammation, which are linked to increased cardiovascular disease risk. We asked whether periodized aerobic exercise training could improve vascular structure and function in patients with COPD. What is the main finding and its importance? Eight weeks of periodized aerobic training did not improve endothelial function, arterial stiffness or systemic inflammation in COPD, despite improvements in aerobic capacity, blood pressure and dyspnoea. Short-term training programmes may not be long enough to improve vascular-related cardiovascular risk in COPD. Chronic obstructive pulmonary disease (COPD) has been associated with endothelial dysfunction and arterial stiffening, which are predictive of future cardiovascular events. Although aerobic exercise improves vascular function in healthy individuals and those with chronic disease, it is unknown whether aerobic exercise can positively modify the vasculature in COPD. We examined the effects of 8 weeks of periodized aerobic training on vascular structure and function and inflammation in 24 patients with COPD (age, 69 ± 7 years; forced expiratory volume in 1 second as a percentage of predicted (FEV 1 %pred), 68 ± 19%) and 20 matched control subjects (age, 64 ± 5 years; FEV 1 %pred, 113 ± 16%) for comparison. Endothelial function was measured using brachial artery flow-mediated dilatation, whereas central and peripheral pulse wave velocity, carotid artery intima-media thickness, carotid compliance, distensibility and β-stiffness index were measured using applanation tonometry and ultrasound. Peak aerobic power (V̇O2 peak ) was measured using an incremental cycling test. Upper and lower body cycling training was performed three times per week for 8 weeks, and designed to optimize vascular adaptation by increasing and sustaining vascular

Long-term consequences of developmental vascular defects on retinal vessel homeostasis and function in a mouse model of Norrie disease.

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Susanne C Beck

Full Text Available Loss of Norrin signalling due to mutations in the Norrie disease pseudoglioma gene causes severe vascular defects in the retina, leading to visual impairment and ultimately blindness. While the emphasis of experimental work so far was on the developmental period, we focus here on disease mechanisms that induce progression into severe adult disease. The goal of this study was the comprehensive analysis of the long-term effects of the absence of Norrin on vascular homeostasis and retinal function. In a mouse model of Norrie disease retinal vascular morphology and integrity were studied by means of in vivo angiography; the vascular constituents were assessed in detailed histological analyses using quantitative retinal morphometry. Finally, electroretinographic analyses were performed to assess the retinal function in adult Norrin deficient animals. We could show that the primary developmental defects not only persisted but developed into further vascular abnormalities and microangiopathies. In particular, the overall vessel homeostasis, the vascular integrity, and also the cellular constituents of the vascular wall were affected in the adult Norrin deficient retina. Moreover, functional analyses indicated to persistent hypoxia in the neural retina which was suggested as one of the major driving forces of disease progression. In summary, our data provide evidence that the key to adult Norrie disease are ongoing vascular modifications, driven by the persistent hypoxic conditions, which are ineffective to compensate for the primary Norrin-dependent defects.

Vascular loops in the anterior inferior cerebellar artery, as identified by magnetic resonance imaging, and their relationship with otologic symptoms

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Luiz de Abreu Junior

Full Text Available Abstract Objective: To use magnetic resonance imaging to identify vascular loops in the anterior inferior cerebellar artery and to evaluate their relationship with otologic symptoms. Materials and Methods: We selected 33 adults with otologic complaints who underwent magnetic resonance imaging at our institution between June and November 2013. Three experienced independent observers evaluated the trajectory of the anterior inferior cerebellar artery in relation to the internal auditory meatus and graded the anterior inferior cerebellar artery vascular loops according to the Chavda classification. Kappa and chi-square tests were used. Values of p < 0.05 were considered significant. Results: The interobserver agreement was moderate. Comparing ears that presented vascular loops with those that did not, we found no association with tinnitus, hearing loss, or vertigo. Similarly, we found no association between the Chavda grade and any otological symptom. Conclusion: Vascular loops do not appear to be associated with otoneurological manifestations.

Characteristics of patients presenting to the vascular emergency department of a tertiary care hospital: a 2-year study

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Kotsikoris Ioannis

2011-11-01

Full Text Available Abstract Background The structure of health care in Greece is receiving increased attention to improve its cost-effectiveness. We sought to examine the epidemiological characteristics of patients presenting to the vascular emergency department of a Greek tertiary care hospital during a 2-year period. We studied all patients presenting to the emergency department of vascular surgery at Red Cross Hospital, Athens, Greece between 1st January 2009 and 31st December 2010. Results Overall, 2452 (49.4% out of 4961 patients suffered from pathologies that should have been treated in primary health care. Only 2509 (50.6% needed vascular surgical intervention. Conclusions The emergency department of vascular surgery in a Greek tertiary care hospital has to treat a remarkably high percentage of patients suitable for the primary health care level. These results suggest that an improvement in the structure of health care is needed in Greece.

Indian-ink perfusion based method for reconstructing continuous vascular networks in whole mouse brain.

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Songchao Xue

Full Text Available The topology of the cerebral vasculature, which is the energy transport corridor of the brain, can be used to study cerebral circulatory pathways. Limited by the restrictions of the vascular markers and imaging methods, studies on cerebral vascular structure now mainly focus on either observation of the macro vessels in a whole brain or imaging of the micro vessels in a small region. Simultaneous vascular studies of arteries, veins and capillaries have not been achieved in the whole brain of mammals. Here, we have combined the improved gelatin-Indian ink vessel perfusion process with Micro-Optical Sectioning Tomography for imaging the vessel network of an entire mouse brain. With 17 days of work, an integral dataset for the entire cerebral vessels was acquired. The voxel resolution is 0.35×0.4×2.0 µm(3 for the whole brain. Besides the observations of fine and complex vascular networks in the reconstructed slices and entire brain views, a representative continuous vascular tracking has been demonstrated in the deep thalamus. This study provided an effective method for studying the entire macro and micro vascular networks of mouse brain simultaneously.

Coincidence of calcified carotid atheromatous plaque, osteoporosis, and periodontal bone loss in dental panoramic radiographs

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Ramesh, Aruna; Ganguly, Rumpa [Dept. of Diagnosis and Health Promotion, Division of Oral and Maxillofacial Radiology, Tufts University School of Dental Medicine, Boston (United States); Soroushian, Sheila [Dept. of Orthodontics, Howard University College of Dentistry, Washington, DC(United States)

2013-12-15

This study was performed to assess the correlation of calcified carotid atheromatous plaque (CCAP), the mandibular cortical index, and periodontal bone loss in panoramic radiographs. One hundred eighty-five panoramic radiographs with CCAP and 234 without this finding were evaluated by 3 observers for the presence of osseous changes related to osteoporosis and periodontal bone loss. Chi-squared and Mann-Whitney U tests were used to compare the two groups for an association of CCAP with the mandibular cortical index and periodontal bone loss, respectively. There was a statistically significant coincidence of CCAP and osseous changes related to osteopenia/osteoporosis, with a p-value <0.001. There was no statistically significant coincidence of CCAP and periodontal bone loss. When comparing the 2 groups, 'With CCAP' and 'Without CCAP', there was a statistically significant association with the mean body mass index (BMI), number of remaining teeth, positive history of diabetes mellitus, and vascular accidents. There was no statistically significant association with gender or a history of smoking. This study identified a possible concurrence of CCAP and mandibular cortical changes secondary to osteopenia/osteoporosis in panoramic radiographs. This could demonstrate the important role of dental professionals in screening for these systemic conditions, leading to timely and appropriate referrals resulting in early interventions and thus improving overall health.

Does weight loss improve semen quality and reproductive hormones? results from a cohort of severely obese men

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Ernst Emil

2011-08-01

Full Text Available Abstract Background A high body mass index (BMI has been associated with reduced semen quality and male subfecundity, but no studies following obese men losing weight have yet been published. We examined semen quality and reproductive hormones among morbidly obese men and studied if weight loss improved the reproductive indicators. Methods In this pilot cohort study, 43 men with BMI > 33 kg/m2 were followed through a 14 week residential weight loss program. The participants provided semen samples and had blood samples drawn, filled in questionnaires, and had clinical examinations before and after the intervention. Conventional semen characteristics as well as sperm DNA integrity, analysed by the sperm chromatin structure assay (SCSA were obtained. Serum levels of testosterone, estradiol, sex hormone-binding globulin (SHBG, luteinizing hormone (LH, follicle-stimulating hormone (FSH, anti-Müllerian hormone (AMH and inhibin B (Inh-B were measured. Results Participants were from 20 to 59 years of age (median = 32 with BMI ranging from 33 to 61 kg/m2. At baseline, after adjustment for potential confounders, BMI was inversely associated with sperm concentration (p = 0.02, total sperm count (p = 0.02, sperm morphology (p = 0.04, and motile sperm (p = 0.005 as well as testosterone (p = 0.04 and Inh-B (p = 0.04 and positively associated to estradiol (p Conclusion This study found obesity to be associated with poor semen quality and altered reproductive hormonal profile. Weight loss may potentially lead to improvement in semen quality. Whether the improvement is a result of the reduction in body weight per se or improved lifestyles remains unknown.

An anisotropically and heterogeneously aligned patterned electrospun scaffold with tailored mechanical property and improved bioactivity for vascular tissue engineering.

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Xu, He; Li, Haiyan; Ke, Qinfei; Chang, Jiang

2015-04-29

The development of vascular scaffolds with controlled mechanical properties and stimulatory effects on biological activities of endothelial cells still remains a significant challenge to vascular tissue engineering. In this work, we reported an innovative approach to prepare a new type of vascular scaffolds with anisotropically and heterogeneously aligned patterns using electrospinning technique with unique wire spring templates, and further investigated the structural effects of the patterned electrospun scaffolds on mechanical properties and angiogenic differentiation of human umbilical vein endothelial cells (HUVECs). Results showed that anisotropically aligned patterned nanofibrous structure was obtained by depositing nanofibers on template in a structurally different manner, one part of nanofibers densely deposited on the embossments of wire spring and formed cylindrical-like structures in the transverse direction, while others loosely suspended and aligned along the longitudinal direction, forming a three-dimensional porous microstructure. We further found that such structures could efficiently control the mechanical properties of electrospun vascular scaffolds in both longitudinal and transverse directions by altering the interval distances between the embossments of patterned scaffolds. When HUVECs were cultured on scaffolds with different microstructures, the patterned scaffolds distinctively promoted adhesion of HUVECs at early stage and proliferation during the culture period. Most importantly, cells experienced a large shape change associated with cell cytoskeleton and nuclei remodeling, leading to a stimulatory effect on angiogenesis differentiation of HUVECs by the patterned microstructures of electrospun scaffolds, and the scaffolds with larger distances of intervals showed a higher stimulatory effect. These results suggest that electrospun scaffolds with the anisotropically and heterogeneously aligned patterns, which could efficiently control the

Dietary self-monitoring, but not dietary quality, improves with use of smartphone app technology in an 8-week weight loss trial.

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Wharton, Christopher M; Johnston, Carol S; Cunningham, Barbara K; Sterner, Danielle

2014-01-01

Dietary self-monitoring is linked to improved weight loss success. Mobile technologies, such as smartphone applications (apps), might allow for improved dietary tracking adherence. The authors assessed the use of a popular smartphone app for dietary self-monitoring and weight loss by comparing it with traditional diet counseling and entry methods. Diet tracking and weight loss were compared across participants during an 8-week weight loss trial. Participants tracked intake using 1 of 3 methods: the mobile app "Lose It!", the memo feature on a smartphone, or a traditional paper-and-pencil method. App users (n = 19) recorded dietary data more consistently compared with the paper-and-pencil group (n = 15; P = .042) but not the memo group (n = 13). All groups lost weight over the course of the study (P = .001), and no difference in weight loss was noted between groups. Smartphone apps could represent a novel and feasible dietary self-monitoring method for individuals. Copyright © 2014 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Adolescents with vascular frontal lesion: A neuropsychological follow up case study.

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Chávez, Clara L; Yáñez, Guillermina; Catroppa, Cathy; Rojas, Sulema; Escartin, Erick; Hearps, Stephen J C; García, Antonio

2016-01-01

The objective of this research was to identify clinically significant changes in cognitive functions in three adolescents who underwent surgery for resection of a focal vascular lesion in the frontal lobe. Cognitive functions, executive function, behavior regulation, emotion regulation, and social abilities were assessed prior to surgery, six and 24 months post-discharge. Significant clinical changes were observed during all the assessments. Cognitive changes after surgery are not homogeneous. Most of the significant clinical changes were improvements. Especially the significant clinical changes presented in EF domains were only improvements; these results suggest that EF were affected by the vascular lesion and benefitted by the surgery. After resection of a vascular lesion between 15 and 16 years of age the affected executive functions can continue the maturation process. Our results highlight the importance that assessments must include emotional aspects, even if deficits in these domains are not presented in the acute phase. Rehabilitation methods should promote the development of skills that help patients and their families to manage the emotional and behavioral changes that emerge once they are discharged from the hospital. Copyright © 2015 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

Intermittent Moderate Energy Restriction Improves Weight Loss Efficiency in Diet-Induced Obese Mice.

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Radhika V Seimon

Full Text Available Intermittent severe energy restriction is popular for weight management. To investigate whether intermittent moderate energy restriction may improve this approach by enhancing weight loss efficiency, we conducted a study in mice, where energy intake can be controlled.Male C57/Bl6 mice that had been rendered obese by an ad libitum diet high in fat and sugar for 22 weeks were then fed one of two energy-restricted normal chow diets for a 12-week weight loss phase. The continuous diet (CD provided 82% of the energy intake of age-matched ad libitum chow-fed controls. The intermittent diet (ID provided cycles of 82% of control intake for 5-6 consecutive days, and ad libitum intake for 1-3 days. Weight loss efficiency during this phase was calculated as (total weight change ÷ [(total energy intake of mice on CD or ID-(total average energy intake of controls]. Subsets of mice then underwent a 3-week weight regain phase involving ad libitum re-feeding.Mice on the ID showed transient hyperphagia relative to controls during each 1-3-day ad libitum feeding period, and overall ate significantly more than CD mice (91.1±1.0 versus 82.2±0.5% of control intake respectively, n = 10, P<0.05. There were no significant differences between CD and ID groups at the end of the weight loss or weight regain phases with respect to body weight, fat mass, circulating glucose or insulin concentrations, or the insulin resistance index. Weight loss efficiency was significantly greater with ID than with CD (0.042±0.007 versus 0.018±0.001 g/kJ, n = 10, P<0.01. Mice on the CD exhibited significantly greater hypothalamic mRNA expression of proopiomelanocortin (POMC relative to ID and control mice, with no differences in neuropeptide Y or agouti-related peptide mRNA expression between energy-restricted groups.Intermittent moderate energy restriction may offer an advantage over continuous moderate energy restriction, because it induces significantly greater weight loss relative

Development of the Australasian vascular surgical audit.

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Bourke, Bernie M; Beiles, Charles Barry; Thomson, Ian A; Grigg, Michael J; Fitridge, Rob

2012-01-01

possible to create and be maintained by a society of surgeons with a membership of just over 200. The 60% compliance rate for complete data entry has created an immediate constitutional challenge for the Society. Future challenges are to improve total participation to an acceptable level and to ensure accurate data entry via a robust validation system. Copyright © 2012 Society for Vascular Surgery. All rights reserved.

The perspective of the vascular surgery trainee on new ACGME regulations, fatigue, resident training, and patient safety.

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De Martino, Randall R; Brewster, L P; Kokkosis, A A; Glass, C; Boros, M; Kreishman, P; Kauvar, D A; Farber, A

2011-11-01

To assess the opinions of vascular surgery trainees on the new Accreditation Council for Graduate Medical Education (ACGME) guidelines. A questionnaire was developed and electronically distributed to trainee members of the Society for Vascular Surgery. Of 238 eligible vascular trainees, 38 (16%) participated. Respondents were predominantly 30 to 35 years of age (47%), male (69%), in 2-year fellowship (73%), and at large academic centers (61%). Trainees report occasionally working while fatigued (63%). Fellows were more likely to report for duty while fatigued (P = .012) than integrated vascular residents. Respondents thought further work-hour restrictions would not improve patient care or training (P life. Respondents reported that duty hours should vary by specialty (81%) and allow flexibility in the last years of training (P balanced against the need to adequately train vascular surgeons.

Bilateral bone conduction devices: improved hearing ability in children with bilateral conductive hearing loss.

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Dun, Catharina A J; Agterberg, Martijn J H; Cremers, Cor W R J; Hol, Myrthe K S; Snik, Ad F M

2013-01-01

The aim of the study was to investigate whether children with bilateral conductive hearing loss benefit from their second device (i.e., the bilateral bone conduction device [BCD]). Speech recognition in noise was assessed in 10 children fitted with bilateral BCDs during childhood. Speech recognition was measured in 2 conditions with both BCDs active. Spatial resolution was tested with the Minimum Audible Angle test in the bilateral and monaural listening conditions. Children demonstrated an improvement in speech recognition when speech was presented from the front and noise was presented from the right-hand side as compared with both speech and noise being presented from the front. The minimum audible angle decreased from 57° in the best monaural condition to 13° in the bilateral condition. The audiological outcomes demonstrate the advantage of bilateral BCD fitting in children with bilateral conductive hearing loss.

Biomarkers of drug-induced vascular injury

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Brott, D.; Gould, S.; Jones, H.; Schofield, J.; Prior, H.; Valentin, J.P; Bjurstrom, S.; Kenne, K.; Schuppe-Koistinen, I.; Katein, A.; Foster-Brown, L.; Betton, G.; Richardson, R.; Evans, G.; Louden, C.

2005-01-01

In pre-clinical safety studies, drug-induced vascular injury is an issue of concern because there are no obvious diagnostic markers for pre-clinical or clinical monitoring and there is an intellectual gap in our understanding of the pathogenesis of this lesion. While vasodilatation and increased shear stress appear to play a role, the exact mechanism(s) of injury to the primary targets, smooth muscle and endothelial cells are unknown. However, evaluation of novel markers for potential clinical monitoring with a mechanistic underpinning would add value in risk assessment and management. This mini review focuses on the progress to identify diagnostic markers of drug-induced vascular injury. Von Willebrand factor (vWF), released upon perturbation of endothelial cells, is transiently increased in plasma prior to morphological evidence of damage in dogs or rats treated with vascular toxicants. Therefore, vWF might be a predictive biomarker of vascular injury. However, vWF is not an appropriate biomarker of lesion progression or severity since levels return to baseline values when there is morphological evidence of injury. A potential mechanistically linked biomarker of vascular injury is caveolin-1. Expression of this protein, localized primarily to smooth muscle and endothelial cells, decreases with the onset of vascular damage. Since vascular injury involves multiple mediators and cell types, evaluation of a panel rather than a single biomarker may be more useful in monitoring early and severe progressive vascular injury

Pediatric interventional radiology: vascular interventions

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Kandasamy, Devasenathipathy; Gamanagatti, Shivanand; Gupta, Arun Kumar

2016-01-01

Pediatric interventional radiology (PIR) comprises a range of minimally invasive diagnostic and therapeutic procedures that are performed using image guidance. PIR has emerged as an essential adjunct to various surgical and medical conditions. Over the years, technology has undergone dramatic and continuous evolution, making this speciality grow. In this review, the authors will discuss various vascular interventional procedures undertaken in pediatric patients. It is challenging for the interventional radiologist to accomplish a successful interventional procedure. There are many vascular interventional radiology procedures which are being performed and have changed the way the diseases are managed. Some of the procedures are life saving and have become the treatment of choice in those patients. The future is indeed bright for the practice and practitioners of pediatric vascular and non-vascular interventions. As more and more of the procedures that are currently being performed in adults get gradually adapted for use in the pediatric population, it may be possible to perform safe and successful interventions in many of the pediatric vascular lesions that are otherwise being referred for surgery. (author)

Injuries as a result of sports and vacation activities: Fractures with concomitant vascular injuries. Diagnosis and treatment concept

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Schlickewei, W.; Kuner, E.H.; Goetze, B.; Spillner, G.

1989-01-01

Extremity fractures with concomitant vascular injuries are surgical emergencies. Especially injuries of the upper extremities require a preoperative angiographic examination for the localization of the vascular lesion. In vascular lesions of the lower extremities a primary angiography is not necessary, if there is an opportunity for an intraoperative radiologic evaluation. In our traumatological department 104 patients were treated over the last 15 years with that combined injury. The concept of immediate stabilization of the fracture with simultaneous or postponed arterial repair has been proved to be appropriate. The fasziotomy as prophylactic procedure of a postischemic compartment syndrome is also a part of our concept during the last years. The late results in our mostly young patients depended on the degree of soft tissue damage and the time of ischemia. The often untreatable nerve lesions contributed to a loss of use of about 30% in the late courses. (orig.) [de

Weight loss and waist reduction is associated with improvement in gastroesophageal disease reflux symptoms: A longitudinal study of 15 295 subjects undergoing health checkups.

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Park, S-K; Lee, T; Yang, H-J; Park, J H; Sohn, C I; Ryu, S; Park, D I

2017-05-01

General obesity and abdominal obesity is an established risk factor of gastroesophageal reflux disease (GERD). However, the influence of weight or waist change on improvement of GERD is unclear. Our aim was to investigate if weight loss or waist reduction improves GERD symptoms and esophagitis. A retrospective longitudinal study of 15 295 subjects who underwent gastroscopy for a health checkup and reported GERD symptoms between 2011 and 2013, and repeated a checkup until 2014 was conducted. The improvement of GERD symptoms and esophagitis according to weight loss (≥-2, -0.5 to -2 kg/m 2 in body mass index [BMI]), waist reduction (≥-5, -0.1 to -0.5 cm) and baseline BMI/waist circumference (WC) categories was assessed using logistic regression. Weight loss or waist reduction was associated with improvement in GERD symptoms only in subjects with general or abdominal obesity. Among subjects with general obesity (BMI ≥25 kg/m 2 ) and decreased ≥2 kg/m 2 in BMI, the adjusted odds ratio (OR) of improvement in GERD symptoms was 2.34 (95% confidence interval [CI] 1.70-2.83). Among subjects with abdominal obesity (WC ≥90 cm) and decreased ≥5 cm in WC, the corresponding OR was 2.16 (95% CI 1.56-2.90). There was no association between weight loss or waist reduction and improvement in esophagitis. Weight loss or waist reduction was associated with improvement in GERD symptoms only in subjects with general or abdominal obesity. Weight loss or waist reduction will be an important treatment option in obese patients. © 2016 John Wiley & Sons Ltd.

Acute Vision Loss Following Endoscopic Sinus Surgery

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Serena Byrd

2017-01-01

Full Text Available A 41-year-old female with a history of uterine cancer and Celiac and Raynaud’s Disease presented to our institution with frequent migraines and nasal congestion. She underwent functional endoscopic sinus surgery (FESS and experienced acute unilateral vision loss postoperatively. Rapid recognition of the etiology and effective treatment are paramount given the permanent and irreversible vision loss that can result. Arterial vasospasm following FESS is rare. Patients with autoimmune diseases have perhaps an increased risk for vasospasm secondary to an increased vasoreactive profile. We present the first documented case of nitroglycerin sublingual therapy to successfully treat ophthalmic artery vasospasm following FESS. Nitroglycerin sublingual therapy is a promising treatment for ophthalmic vasospasm secondary to its ability to cross the blood-ocular barrier, its rapid onset of action, and its ability to promote relaxation of vascular smooth muscle.

Benfotiamine attenuates nicotine and uric acid-induced vascular endothelial dysfunction in the rat.

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Balakumar, Pitchai; Sharma, Ramica; Singh, Manjeet

2008-01-01

The study has been designed to investigate the effect of benfotiamine, a thiamine derivative, in nicotine and uric acid-induced vascular endothelial dysfunction (VED) in rats. Nicotine (2 mg kg(-1)day(-1), i.p., 4 weeks) and uric acid (150 mg kg(-1)day(-1), i.p., 3 weeks) were administered to produce VED in rats. The development of VED was assessed by employing isolated aortic ring preparation and estimating serum and aortic concentration of nitrite/nitrate. Further, the integrity of vascular endothelium was assessed using the scanning electron microscopy (SEM) of thoracic aorta. Moreover, the oxidative stress was assessed by estimating serum thiobarbituric acid reactive substances (TBARS) and aortic superoxide anion generation. The administration of nicotine and uric acid produced VED by impairing the integrity of vascular endothelium and subsequently decreasing serum and aortic concentration of nitrite/nitrate and attenuating acetylcholine-induced endothelium dependent relaxation. Further, nicotine and uric acid produced oxidative stress, which was assessed in terms of increase in serum TBARS and aortic superoxide generation. However, treatment with benfotiamine (70 mg kg(-1)day(-1), p.o.) or atorvastatin (30 mg kg(-1)day(-1) p.o., a standard agent) markedly prevented nicotine and uric acid-induced VED and oxidative stress by improving the integrity of vascular endothelium, increasing the concentration of serum and aortic nitrite/nitrate, enhancing the acetylcholine-induced endothelium dependent relaxation and decreasing serum TBARS and aortic superoxide anion generation. Thus, it may be concluded that benfotiamine reduces the oxidative stress and consequently improves the integrity of vascular endothelium and enhances the generation of nitric oxide to prevent nicotine and uric acid-induced experimental VED.

Deferoxamine improves coronary vascular responses to sympathetic stimulation in patients with type 1 diabetes mellitus

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Hattori, Naoya; Bengel, Frank M.; Nekolla, Stephan G.; Drzezga, Alexander E.; Schwaiger, Markus [Nuklearmedizinische Klinik und Poliklinik, Klinikum Rechts der Isar, Technischen Universitaet Muenchen (Germany); Schnell, Oliver; Rihl, Julian; Standl, Eberhard [Diabetes Research Center, Schwabing City Hospital, Munich (Germany)

2002-07-01

Effects of oxygen-derived free radicals are suggested to be a potential pathogenic factor for endothelial dysfunction. In this study we sought to evaluate the effect of hydroxyl radicals on the human coronary vascular bed in type I diabetes mellitus using positron emission tomography (PET). Thirteen patients with type 1 diabetes underwent PET using nitrogen-13 ammonia at rest and during sympathetic stimulation with the cold pressor test (CPT). The rest-stress study protocol was repeated twice (on different days) using pre-stress infusion of either saline as placebo or deferoxamine, an iron chelator which inhibits generation of hydroxyl radicals. At rest, global MBF was higher in diabetics than in normal controls (78.1{+-}17.5 vs 63.2{+-}14.9 mg 100 g{sup -1} min{sup -1}, P<0.05) and myocardial vascular resistance (MVR) showed a trend towards lower values (patients, 1.28{+-}0.35; controls, 1.55{+-}0.32, P=NS). CPT increased MBF in all controls while 7/13 diabetics responded normally. CPT decreased MVR in 10/13 controls but in only 4/13 diabetics. There was no significant difference in the duration of diabetes, HbA1c, daily insulin dose, body mass index, or lipid profiles between patients with and patients without abnormal MBF or MVR responses. Pre-stress infusion of deferoxamine normalized MBF response in all six patients, and MVR response in six of the nine patients. Another group consisting of seven patients underwent a rest-rest protocol after infusion of deferoxamine and saline to investigate the effect of deferoxamine on resting MBF. Deferoxamine did not change the resting MBF (deferoxamine, 81{+-}17 ml 100 g{sup -1} min{sup -1}; saline, 75{+-}19 ml 100 g{sup -1} min{sup -1}, P=NS) or MVR (deferoxamine, 1.0{+-}0.5 mmHg ml{sup -1} 100 g{sup -1} min{sup -1}; saline, 1.2{+-}0.6 mmHg ml{sup -1} 100 g{sup -1} min{sup -1}, P=NS). In conclusion, inhibition of hydroxyl radical formation using deferoxamine significantly improved the responses of coronary

Renal posttransplant's vascular complications

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Bašić Dragoslav

2003-01-01

Full Text Available INTRODUCTION Despite high graft and recipient survival figures worldwide today, a variety of technical complications can threaten the transplant in the postoperative period. Vascular complications are commonly related to technical problems in establishing vascular continuity or to damage that occurs during donor nephrectomy or preservation [13]. AIM The aim of the presenting study is to evaluate counts and rates of vascular complications after renal transplantation and to compare the outcome by donor type. MATERIAL AND METHODS A total of 463 kidneys (319 from living related donor LD and 144 from cadaveric donor - CD were transplanted during the period between June 1975 and December 1998 at the Urology & Nephrology Institute of Clinical Centre of Serbia in Belgrade. Average recipients' age was 33.7 years (15-54 in LD group and 39.8 (19-62 in CD group. Retrospectively, we analyzed medical records of all recipients. Statistical analysis is estimated using Hi-squared test and Fischer's test of exact probability. RESULTS Major vascular complications including vascular anastomosis thrombosis, internal iliac artery stenosis, internal iliac artery rupture obliterant vasculitis and external iliac vein rupture were analyzed. In 25 recipients (5.4% some of major vascular complications were detected. Among these cases, 22 of them were from CD group vs. three from LD group. Relative rate of these complications was higher in CD group vs. LD group (p<0.0001. Among these complications dominant one was vascular anastomosis thrombosis which occurred in 18 recipients (17 from CD vs. one from LD. Of these recipients 16 from CD lost the graft, while the rest of two (one from each group had lethal outcome. DISCUSSION Thrombosis of renal allograft vascular anastomosis site is the most severe complication following renal transplantation. In the literature, renal allograft thrombosis is reported with different incidence rates, from 0.5-4% [14, 15, 16]. Data from the

Coronary vascular age: An alternate means for predicting stress-induced myocardial ischemia in patients with suspected coronary artery disease.

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Nappi, Carmela; Gaudieri, Valeria; Acampa, Wanda; Arumugam, Parthiban; Assante, Roberta; Zampella, Emilia; Mannarino, Teresa; Mainolfi, Ciro Gabriele; Imbriaco, Massimo; Petretta, Mario; Cuocolo, Alberto

2018-01-22

Coronary artery calcium (CAC) can be used to estimate vascular age in adults, providing a convenient transformation of CAC from Agatston units into a year's scale. We investigated the role of coronary vascular age in predicting stress-induced myocardial ischemia in subjects with suspected coronary artery disease (CAD). A total of 717 subjects referred to CAC scoring and 82 Rb PET/CT stress-rest myocardial perfusion imaging for suspected CAD were studied. CAC score was measured according to the Agatston method and coronary vascular age by equating estimated CAD risk for chronological age and CAC using the formula 39.1 + 7.25 × ln(CAC + 1). Stress-induced ischemia was present in 105 (15%) patients. Mean chronological age, CAC score, and coronary vascular age were higher (all P age was added to clinical variables. Including vascular age in the model, the global Chi square further increased from 68.77 to 106.38 (P age to clinical data, continuous net reclassification improvement (cNRI) was 0.57, while adding vascular age to clinical data and chronological age cNRI was 0.62. At decision curve analysis, the model including vascular age was associated with the highest net benefit compared to the model including only clinical data, to the model including chronological age and clinical data, and to a strategy considering that all patients had ischemia. The model including vascular age also showed the largest reduction in false-positive rate without missing any ischemic patients. In subjects with suspected CAD, coronary vascular age is strongly associated with stress-induced ischemia. The communication of a given vascular age would have a superior emotive impact improving observance of therapies and healthier lifestyles.

Improved Wojcik's eavesdropping attack on ping-pong protocol without eavesdropping-induced channel loss

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Zhang Zhanjun [School of Physics and Material Science, Anhui University, Hefei 230039 (China) and Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China)]. E-mail: zhangzj@wipm.ac.cn; Li Yong [Department of Physics, Huazhong Normal University, Wuhan 430079 (China); Man Zhongxiao [Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China)

2005-06-27

The eavesdropping scheme proposed by Wojcik [Phys. Rev. Lett. 90 (2003) 157901] on the ping-pong protocol [Phys. Rev. Lett. 89 (2002) 187902] is improved by constituting a new set of attack operations. The improved scheme has a zero eavesdropping-induced channel loss and produces perfect anticorrelation. Therefore, the eavesdropper Eve can safely attack all the transmitted bits and the eavesdropping information gain can always exceed the legitimate user's information gain in the whole domain of the quantum channel transmission efficiency {eta}, i.e., [0,100%]. This means that the ping-pong protocol can be completely eavesdropped in its original version. But the improvement of the ping-pong protocol security produced by Wojcik is also suitable for our eavesdropping attack.

Overview of vascular disease

International Nuclear Information System (INIS)

Bisset, G.S. III

1998-01-01

Vascular disease in the pediatric population is a poorly understood process which is often underestimated in its incidence. The common beginnings of such ubiquitous diseases as atherosclerosis manifest themselves at a cellular level shortly after birth. Other common systemic disorders, including congestive heart failure and sepsis, are also intricately associated with dysfunctional vasculature. Progress in the understanding of normal and pathophysiologic processes within the vascular system begins with the 'control center' - the endothelial cell. The purpose of this review is to consolidate a body of knowledge on the processes that occur at the cellular level within the blood vessel wall, and to simplify the understanding of how imbalances in these physiologic parameters result in vascular disease. (orig.)

Vascularized nerve grafts for lower extremity nerve reconstruction.

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Terzis, Julia K; Kostopoulos, Vasileios K

2010-02-01

Vascularized nerve grafts (VNG) were introduced in 1976 but since then, there have been no reports of their usage in lower extremity reconstruction systematically. The factors influencing outcomes as well as a comparison with conventional nerve grafts will be presented.Since 1981, 14 lower extremity nerve injuries in 12 patients have been reconstructed with VNG. Common peroneal nerve was injured in 12 and posterior tibial nerve in 5 patients. The level of the injury was at the knee or thigh. Twelve sural nerves were used as VNG with or without concomitant vascularized posterior calf fascia.All patients regained improved sensibility and adequate posterior tibial nerve function. For common peroneal nerve reconstructions, all patients with denervation time less than 6 months regained muscle strength of grade at least 4, even when long grafts were used for defects of 20 cm or more. Late cases, yielded inadequate muscle function even with the use of VNG.Denervation time of 6 months or less was critical for reconstruction with vascularized nerve graft. Not only the results were statistically significant compared with late cases, but also all early operated patients achieved excellent results. VNG are strongly recommended in traction avulsion injuries of the lower extremity with lengthy nerve damage.

Neuropsychological performance in patients with subcortical stroke Perfil neuropsicológico em pacientes com lesões vasculares subcorticais

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Silviane Pinheiro Campos de Andrade

2012-05-01

Full Text Available Vascular cognitive impairment (VCI is characterized by cognitive compromise predominantly of executive dysfunction. OBJECTIVES: To assess cognitive functions in VCI, focusing on executive functions, to observe functional losses in relation to activities of daily living (ADLs and to detect early symptoms prior to the onset of dementia. METHODS: We evaluated healthy subjects matched for gender, education and age to patients with diagnosis of subcortical vascular disease who had a stroke classified into three groups: 1 vascular lesions and no impairment; 2 vascular cognitive impairment with no dementia (VCIND; 3 vascular dementia (VaD. RESULTS AND DISCUSSION: The performance on neuropsychological tests differed among groups, worsening with increased impairment level. The probable VaD group demonstrated impaired performance in memory, processing speed and verbal production, while the VCIND group showed attention deficits. CONCLUSION: Impairment in executive functions and difficulties in ADLs allow us to differentiate levels of impairment in groups of subcortical vascular disease.O comprometimento cognitivo vascular (CCV é caracterizado por comprometimento cognitivo predominantemente sob a forma de disfunção executiva. OBJETIVOS: Avaliar as funções cognitivas no CCV, enfocando as funções executivas, observar as perdas funcionais em relação às atividades cotidianas (AVDs e detectar os primeiros sintomas antes do início da demência. MÉTODOS: Foram avaliados indivíduos controles saudáveis pareados por sexo, escolaridade e idade com pacientes com diagnóstico de doença vascular subcortical que sofreram derrame classificados em três grupos: 1 lesões vasculares sem déficit; 2 comprometimento cognitivo vascular sem demência (CCVSD; 3 demência vascular (DV. RESULTADOS E DISCUSSÃO: O desempenho em testes neuropsicológicos diferiu entre os grupos, sendo o desempenho tanto pior quanto maior o comprometimento. O grupo DV prov

Exercise Training Could Improve Age-Related Changes in Cerebral Blood Flow and Capillary Vascularity through the Upregulation of VEGF and eNOS

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Sheepsumon Viboolvorakul

2014-01-01

Full Text Available This study aimed to investigate the effect of exercise training on age-induced microvascular alterations in the brain. Additionally, the association with the protein levels of vascular endothelial growth factor (VEGF and endothelial nitric oxide synthase (eNOS was also assessed. Male Wistar rats were divided into four groups: sedentary-young (SE-Young, n=5, sedentary aged (SE-Aged, n=8, immersed-aged (IM-Aged, n=5, and exercise trained-aged (ET-Aged, 60 minutes/day and 5 days/week for 8 weeks, n=8 rats. The MAPs of all aged groups, SE-Aged, IM-Aged, and ET-Aged, were significantly higher than that of the SE-Young group. The regional cerebral blood flow (rCBF in the SE-Aged and IM-Aged was significantly decreased as compared to SE-Young groups. However, rCBF of ET-Aged group was significantly higher than that in the IM-Aged group (P<0.05. Moreover, the percentage of capillary vascularity (%CV and the levels of VEGF and eNOS in the ET-Aged group were significantly increased compared to the IM-Aged group (P<0.05. These results imply that exercise training could improve age-induced microvascular changes and hypoperfusion closely associated with the upregulation of VEGF and eNOS.

Regionalization of Emergent Vascular Surgery for Patients With Ruptured AAA Improves Outcomes.

Science.gov (United States)

Warner, Courtney J; Roddy, Sean P; Chang, Benjamin B; Kreienberg, Paul B; Sternbach, Yaron; Taggert, John B; Ozsvath, Kathleen J; Stain, Steven C; Darling, R Clement

2016-09-01

Safe and efficient endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysm (r-AAA) requires advanced infrastructure and surgical expertise not available at all US hospitals. The objective was to assess the impact of regionalizing r-AAA care to centers equipped for both open surgical repair (r-OSR) and EVAR (r-EVAR) by vascular surgeons. A retrospective review of all patients with r-AAA undergoing open or endovascular repair in a 12-hospital region. Patient demographics, transfer status, type of repair, and intraoperative variables were recorded. Outcomes included perioperative morbidity and mortality. Four hundred fifty-one patients with r-AAA were treated from 2002 to 2015. Three hundred twenty-one patients (71%) presented initially to community hospitals (CHs) and 130 (29%) presented to the tertiary medical center (MC). Of the 321 patients presenting to CH, 133 (41%) were treated locally (131 OSR; 2 EVAR) and 188 (59%) were transferred to the MC. In total, 318 patients were treated at the MC (122 OSR; 196 EVAR). At the MC, r-EVAR was associated with a lower mortality rate than r-OSR (20% vs 37%, P = 0.001). Transfer did not influence r-EVAR mortality (20% in r-EVAR presenting to MC vs 20% in r-EVAR transferred, P > 0.2). Overall, r-AAA mortality at the MC was 20% lower than CH (27% vs 46%, P AAA repair to centers equipped for both r-EVAR and r-OSR decreased mortality by approximately 20%. Transfer did not impact the mortality of r-EVAR at the tertiary center. Care of r-AAA in the US should be centralized to centers equipped with available technology and vascular surgeons.

Peptide-modified PELCL electrospun membranes for regulation of vascular endothelial cells

Energy Technology Data Exchange (ETDEWEB)

Zhou, Fang [School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072 (China); Jia, Xiaoling [Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083 (China); Yang, Yang [School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072 (China); Yang, Qingmao; Gao, Chao [Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083 (China); Zhao, Yunhui [School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072 (China); Fan, Yubo, E-mail: yubofan@buaa.edu.cn [Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083 (China); National Research Center for Rehabilitation Technical Aids, Beijing 100176 (China); Yuan, Xiaoyan, E-mail: yuanxy@tju.edu.cn [School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072 (China)

2016-11-01

The efficiency of biomaterials used in small vascular repair depends greatly on their ability to interact with vascular endothelial cells (VECs). Rapid endothelialization of the vascular grafts is a promising way to prevent thrombosis and intimal hyperplasia. In this work, modification of electrospun membranes of poly(ethylene glycol)-b-poly(L-lactide-co-ε-caprolactone) (PELCL) by three different peptides for regulation of VECs were studied in order to obtain ideal bioactive biomaterials as small diameter vascular grafts. QK (a mimetic peptide to vascular endothelial growth factor), Arg-Glu-Asp-Val (REDV, a specific adhesive peptide to VECs) and Val-Ala-Pro-Gly (VAPG, a specific adhesive peptide to vascular smooth muscle cells) were investigated. Surface properties of the modified membranes and the response of VECs were verified. It was found that protein adsorption and platelet adhesion were effectively suppressed with the introduction of QK, REDV or VAPG peptides on the PELCL electrospun membranes. Both QK- and REDV-modified electrospun membranes could accelerate the proliferation of VECs in the first 9 days, and the QK-modified electrospun membrane promoted cell proliferation more significantly than the REDV-modified one. The REDV-modified PELCL membrane was the most favorable for VECs adhesion than QK- and VAPG-modified membranes. It was suggested that QK- or REDV-modified PELCL electrospun membranes may have great potential applications in cardiovascular biomaterials for rapid endothelialization in situ. - Highlights: • A series of peptide-modified PELCL electrospun membranes were prepared. • Hemocompatibility of the membranes was greatly improved by the modification. • QK-modified PELCL membrane promoted VECs proliferation more significantly. • REDV-modified PELCL membrane was the most favorable for VEC adhesion.

Peptide-modified PELCL electrospun membranes for regulation of vascular endothelial cells

International Nuclear Information System (INIS)

Zhou, Fang; Jia, Xiaoling; Yang, Yang; Yang, Qingmao; Gao, Chao; Zhao, Yunhui; Fan, Yubo; Yuan, Xiaoyan

2016-01-01

The efficiency of biomaterials used in small vascular repair depends greatly on their ability to interact with vascular endothelial cells (VECs). Rapid endothelialization of the vascular grafts is a promising way to prevent thrombosis and intimal hyperplasia. In this work, modification of electrospun membranes of poly(ethylene glycol)-b-poly(L-lactide-co-ε-caprolactone) (PELCL) by three different peptides for regulation of VECs were studied in order to obtain ideal bioactive biomaterials as small diameter vascular grafts. QK (a mimetic peptide to vascular endothelial growth factor), Arg-Glu-Asp-Val (REDV, a specific adhesive peptide to VECs) and Val-Ala-Pro-Gly (VAPG, a specific adhesive peptide to vascular smooth muscle cells) were investigated. Surface properties of the modified membranes and the response of VECs were verified. It was found that protein adsorption and platelet adhesion were effectively suppressed with the introduction of QK, REDV or VAPG peptides on the PELCL electrospun membranes. Both QK- and REDV-modified electrospun membranes could accelerate the proliferation of VECs in the first 9 days, and the QK-modified electrospun membrane promoted cell proliferation more significantly than the REDV-modified one. The REDV-modified PELCL membrane was the most favorable for VECs adhesion than QK- and VAPG-modified membranes. It was suggested that QK- or REDV-modified PELCL electrospun membranes may have great potential applications in cardiovascular biomaterials for rapid endothelialization in situ. - Highlights: • A series of peptide-modified PELCL electrospun membranes were prepared. • Hemocompatibility of the membranes was greatly improved by the modification. • QK-modified PELCL membrane promoted VECs proliferation more significantly. • REDV-modified PELCL membrane was the most favorable for VEC adhesion.

Multifunctional silk-heparin biomaterials for vascular tissue engineering applications

Science.gov (United States)

Seib, F. Philipp; Herklotz, Manuela; Burke, Kelly A.; Maitz, Manfred F.; Werner, Carsten; Kaplan, David L.

2013-01-01

Over the past 30 years, silk has been proposed for numerous biomedical applications that go beyond its traditional use as a suture material. Silk sutures are well tolerated in humans, but the use of silk for vascular engineering applications still requires extensive biocompatibility testing. Some studies have indicated a need to modify silk to yield a hemocompatible surface. This study examined the potential of low molecular weight heparin as a material for refining silk properties by acting as a carrier for vascular endothelial growth factor (VEGF) and improving silk hemocompatibility. Heparinized silk showed a controlled VEGF release over 6 days; the released VEGF was bioactive and supported the growth of human endothelial cells. Silk samples were then assessed using a humanized hemocompatibility system that employs whole blood and endothelial cells. The overall thrombogenic response for silk was very low and similar to the clinical reference material polytetrafluoroethylene. Despite an initial inflammatory response to silk, apparent as complement and leukocyte activation, the endothelium was maintained in a resting, anticoagulant state. The low thrombogenic response and the ability to control VEGF release support the further development of silk for vascular applications. PMID:24099708

Rates of Water Loss and Uptake in Recalcitrant Fruits of Quercus Species Are Determined by Pericarp Anatomy

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Xia, Ke; Daws, Matthew I.; Stuppy, Wolfgang; Zhou, Zhe-Kun; Pritchard, Hugh W.

2012-01-01

Desiccation-sensitive recalcitrant seeds and fruits are killed by the loss of even moderate quantities of water. Consequently, minimizing the rate of water loss may be an important ecological factor and evolutionary driver by reducing the risk of mortality during post-dispersal dry-spells. For recalcitrant fruits of a range of Quercus species, prolonged drying times have been observed previously. However, the underlying mechanism(s) for this variation is unknown. Using nine Quercus species we investigated the major route(s) of water flow into and out of the fruits and analysed the relative importance of the different pericarp components and their anatomy on water uptake/loss. During imbibition (rehydration), the surface area of the cupule scar and the frequency and area of the vascular bundles contained therein were significantly correlated with the rates of water uptake across the scar. The vascular bundles serving the apex of the fruit were a minor contributor to overall water. Further, the rate of water uptake across the remainder of the pericarp surface was significantly correlated with the thickness of the vascularised inner layer in the pericarp. Fruits of Q. franchetii and Q. schottkyana dried most slowly and had a comparatively small scar surface area with few vascular bundles per unit area. These species inhabit drier regions than the other species studied, suggesting these anatomical features may have ecological value by reducing the risk of desiccation stress. However, this remains to be tested in the field. PMID:23071795

Bioengineering vascularized tissue constructs using an injectable cell-laden enzymatically crosslinked collagen hydrogel derived from dermal extracellular matrix.

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Kuo, Kuan-Chih; Lin, Ruei-Zeng; Tien, Han-Wen; Wu, Pei-Yun; Li, Yen-Cheng; Melero-Martin, Juan M; Chen, Ying-Chieh

2015-11-01

-Ph hydrogel resulted in not only improving the long-term differentiation of transplanted MSCs into mineralized osteoblasts, but the collagen-Ph hydrogel also improved an increased of adipocytes within the vascularized bioengineered tissue in a mouse after 1 month of implantation. We reported a method for preparing autologous extracellular matrix scaffolds, murine collagen-Ph hydrogels, and demonstrated its suitability for use in supporting human progenitor cell-based formation of 3D vascular networks in vitro and in vivo. Results showed extensive human vascular networks can be generated within 7 days, engineered vascular density inside collagen-Ph constructs can be manipulated through refinable mechanical properties and proteolytic degradability, and these networks can form functional anastomoses with existing vasculature to further support the survival of host muscle tissues. Moreover, optimized conditions of cell-laden collagen-Ph hydrogel resulted in not only improving the long-term differentiation of transplanted MSCs into mineralized osteoblasts, but the collagen-Ph hydrogel also improved an increased of adipocytes within the vascularized bioengineered tissue in a mouse. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Factors modulating bioavailability of quercetin-related flavonoids and the consequences of their vascular function.

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Terao, Junji

2017-09-01

Nowadays dietary flavonoids attract much attention in the prevention of chronic diseases. Epidemiological and intervention studies strongly suggest that flavonoid intake has beneficial effects on vascular health. It is unlikely that flavonoids act as direct antioxidants, although oxidative stress profoundly contributes to vascular impairment leading to cardiovascular diseases. Instead, flavonoids may exert their function by tuning the cellular redox state to an adaptive response or tolerable stress. However, the optimum intake of flavonoids from supplements or diet has not been clarified yet, because a number of exogenous and endogenous factors modulating their bioavailability affect their vascular function. This review will focus on the current knowledge of the bioavailability and vascular function of quercetin as a representative of antioxidative flavonoids. Current intervention studies imply that intake of quercetin-rich onion improves vascular health. Onion may be superior to quercetin supplement from the viewpoint of quercetin bioavailability, probably because the food matrix enhances the intestinal absorption of quercetin. α-Glucosylation increases its bioavailability by elevating the accessibility to the absorptive cells. Prenylation may enhance bioaccumulation at the target site by increasing the cellular uptake. However, these chemical modifications do not guarantee health benefits to the vascular system. Dietary quercetin is exclusively present as their conjugated form in the blood stream. Quercetin may exert its vascular function as an aglycone within macrophage cells after inflammation-induced deconjugation and as conjugated metabolites by targeting endothelial cells. The relationship between the bioavailability and bio-efficacy should be clarified, to evaluate the vascular function of a wide variety of dietary flavonoids. Copyright © 2017 Elsevier Inc. All rights reserved.

Small Intestinal Bypass Induces a Persistent Weight-Loss Effect and Improves Glucose Tolerance in Obese Rats.

Science.gov (United States)

Cao, Jiaqing; Ren, Quan; Tan, Cai; Duan, Jinyuan

2017-07-01

This study investigated the role of proximal small intestinal bypass (PSIB) and distal small intestinal bypass (DSIB) as well as their long-term effects on weight loss and glucose metabolism in high-sugar and high-fat diet-induced obese rats. Sprague-Dawley rats were divided into four groups: PSIB, bypassing 60% of the proximal small intestine length; DSIB, bypassing 60% of the distal small intestine length; sham-operated (Sham) animals; and control animals. All rats were fed a high-sugar and high-fat diet after surgery. The primary outcome measures were body weight, food intake, fasting blood glucose (FBG) levels, oral glucose tolerance test (OGTT), and the insulin tolerance test (ITT). Global body weight (BW) and food intake in the PSIB and DSIB groups were lower than those in the Sham group at postoperative week 2. BW and food intake in the PSIB group were lower than those in the DSIB group at postoperative week 24. The PSIB and DSIB groups exhibited improvement in glucose tolerance at postoperative weeks 4, 8, and 24. The PSIB and DSIB groups exhibited improvement in FBG at postoperative week 24, and only the DSIB group exhibited improvement in insulin sensitivity. This study provides experimental evidence that PSIB surgery induced a better and more persistent weight loss effect than DSIB surgery and that the two types of intestinal bypass surgeries yielded equivalent and stable long-term improvement in glucose tolerance in an obese rat model.

Enhanced Recovery after Vascular Surgery

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Milena D. Stojanovic

2018-01-01

Full Text Available The beginnings of the enhanced recovery after surgery (ERAS program were first developed for patients in colorectal surgery, and after it was established as the standard of care in this surgical field, it began to be applied in many others surgical areas. This is multimodal, evidence-based approach program and includes simultaneous optimization of preoperative status of patients, adequate selection of surgical procedure and postoperative management. The aim of this program is to reduce complications, the length of hospital stay and to improve the patients outcome. Over the past decades, special attention was directed to the postoperative management in vascular surgery, especially after major vascular surgery because of the great risk of multiorgan failure, such as: respiratory failure, myocardial infarction, hemodynamic instability, coagulopathy, renal failure, neurological disorders, and intra-abdominal complications. Although a lot of effort was put into it, there is no unique acceptable program for ERAS in this surgical field, and there is still a need to point out the factors responsible for postoperative outcomes of these patients. So far, it is known that special attention should be paid to already existing diseases, type and the duration of the surgical intervention, hemodynamic and fluid management, nutrition, pain management, and early mobilization of patients.

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

International Nuclear Information System (INIS)

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

2012-01-01

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

Photoacoustic imaging of breast tumor vascularization: a comparison with MRI and histopathology

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Heijblom, Michelle; Piras, Daniele; van den Engh, Frank M.; Klaase, Joost M.; Brinkhuis, Mariël.; Steenbergen, Wiendelt; Manohar, Srirang

2013-06-01

Breast cancer is the most common form of cancer and the leading cause of cancer death among females. Early diagnosis improves the survival chances for the disease and that is why there is an ongoing search for improved methods for visualizing breast cancer. One of the hallmarks of breast cancer is the increase in tumor vascularization that is associated with angiogenesis: a crucial factor for survival of malignancies. Photoacoustic imaging can visualize the malignancyassociated increased hemoglobin concentration with optical contrast and ultrasound resolution, without the use of ionizing radiation or contrast agents and is therefore theoretically an ideal method for breast imaging. Previous clinical studies using the Twente Photoacoustic Mammoscope (PAM), which works in forward mode using a single wavelength (1064 nm), showed that malignancies can indeed be identified in the photoacoustic imaging volume as high contrast areas. However, the specific appearance of the malignancies led to questions about the contrast mechanism in relation to tumor vascularization. In this study, the photoacoustic lesion appearance obtained with an updated version of PAM is compared with the lesion appearance on Magnetic Resonance Imaging (MRI), both in general (19 patients) and on an individual basis (7 patients). Further, in 3 patients an extended histopathology protocol is being performed in which malignancies are stained for vascularity using an endothelial antibody: CD31. The correspondence between PAM and MRI and between PAM and histopathology makes it likely that the high photoacoustic contrast at 1064 nm is indeed largely the consequence of the increased tumor vascularization.

WNT5A-JNK regulation of vascular insulin resistance in human obesity.

Science.gov (United States)

Farb, Melissa G; Karki, Shakun; Park, Song-Young; Saggese, Samantha M; Carmine, Brian; Hess, Donald T; Apovian, Caroline; Fetterman, Jessica L; Bretón-Romero, Rosa; Hamburg, Naomi M; Fuster, José J; Zuriaga, María A; Walsh, Kenneth; Gokce, Noyan

2016-12-01

Obesity is associated with the development of vascular insulin resistance; however, pathophysiological mechanisms are poorly understood. We sought to investigate the role of WNT5A-JNK in the regulation of insulin-mediated vasodilator responses in human adipose tissue arterioles prone to endothelial dysfunction. In 43 severely obese (BMI 44±11 kg/m 2 ) and five metabolically normal non-obese (BMI 26±2 kg/m 2 ) subjects, we isolated arterioles from subcutaneous and visceral fat during planned surgeries. Using videomicroscopy, we examined insulin-mediated, endothelium-dependent vasodilator responses and characterized adipose tissue gene and protein expression using real-time polymerase chain reaction and Western blot analyses. Immunofluorescence was used to quantify endothelial nitric oxide synthase (eNOS) phosphorylation. Insulin-mediated vasodilation was markedly impaired in visceral compared to subcutaneous vessels from obese subjects (p<0.001), but preserved in non-obese individuals. Visceral adiposity was associated with increased JNK activation and elevated expression of WNT5A and its non-canonical receptors, which correlated negatively with insulin signaling. Pharmacological JNK antagonism with SP600125 markedly improved insulin-mediated vasodilation by sixfold (p<0.001), while endothelial cells exposed to recombinant WNT5A developed insulin resistance and impaired eNOS phosphorylation (p<0.05). We observed profound vascular insulin resistance in the visceral adipose tissue arterioles of obese subjects that was associated with up-regulated WNT5A-JNK signaling and impaired endothelial eNOS activation. Pharmacological JNK antagonism markedly improved vascular endothelial function, and may represent a potential therapeutic target in obesity-related vascular disease. © The Author(s) 2016.

Small GTP-Binding Protein Rac Is an Essential Mediator of Vascular Endothelial Growth Factor-Induced Endothelial Fenestrations and Vascular Permeability

DEFF Research Database (Denmark)

Eriksson, A.; Cao, R.; Tritsaris, K.

2003-01-01

fenestrated endothelium, a feature linked with increased vascular permeability. A cell-permeable Rac antagonist (TAT-RacN17) converted VEGF-induced, leaky vascular plexuses into well-defined vascular networks. In addition, this Rac mutant blocked formation of VEGF-induced endothelial fenestrations...... in mediation of VEGF-induced vascular permeability but less so in neovascularization. This may have conceptual implications for applying Rac antagonists in treatment and prevention of VEGF-induced vascular leakage and edema in connection with ischemic disorders....

Does weight loss improve semen quality and reproductive hormones? Results from a cohort of severely obese men

DEFF Research Database (Denmark)

Håkonsen, Linn Berger; Thulstrup, Ane Marie; Aggerholm, Anette Skærbech

2011-01-01

A high body mass index (BMI) has been associated with reduced semen quality and male subfecundity, but no studies following obese men losing weight have yet been published. We examined semen quality and reproductive hormones among morbidly obese men and studied if weight loss improved...

Trends in a changing vascular practice environment for members of the Society for Vascular Surgery

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Matthews, Mika A. B.; Satiani, Bhagwan; Lohr, Joann M.

2013-01-01

Objective To survey the Society for Vascular Surgery (SVS) membership with regard to practice trends related to work effort, employment status, practice ownership, endovascular cases, and anticipated changes in practice in the near future. Methods A survey questionnaire was developed to gather information about member demographics and practice, hours worked, full-time (FT) or part-time status, employment status, practice ownership, competition for referrals, proportion of endovascular vs open procedures, and anticipated changes in practice in the next 3 years. We used SurveyMonkey and distributed the survey to all active vascular surgeon (VS) members of the SVS. Results The response rate was 207 of 2230 (10.7%). Two thirds were in private practice, and 21% were in solo practice. Twenty-four percent were employed by hospitals/health systems. Those VS under the age of 50 years were more likely to exclusively practice vascular surgery compared with VS over the age of 50 years (P = .0003). Sixty-eight of the physicians (32.7%) were between 50 and 59 years old, 186 (90.3%) were men, 192 (92.8%) worked FT (>36 hours of patient care per week), and almost two thirds worked >60 hours per week. Those in physician-owned practices worked >40 hours of patient care per week more often than did FT employed VS (P = .012). Younger VS (age 50% of their workload being endovascular compared with older VS (age ≥50 years; P 40 hours of patient care per week than are FT employed VS. Longitudinal surveys of SVS members are imperative to help tailor educational, training, and practice management offerings, guide governmental activities, advocate for issues important to members, improve branding initiatives, and sponsor workforce analyses. PMID:23254185

Complicação vascular de osteocondroma: relato de caso Vascular complication of osteochondroma: case report

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Fábio André Tornquist

2007-03-01

Full Text Available Osteocondromas ou exostoses são os tumores benignos mais comuns do tecido ósseo. Eles surgem durante o período de crescimento e, raramente, são responsáveis por complicações vasculares. No presente relato, reportamos um caso de paciente com osteocondroma no membro inferior e complicação vascular provocada pela compressão da artéria poplítea. O paciente apresentava queixas de dor em membro inferior direito quando foi investigado com angiografia e radiografia, que identificaram a lesão vascular e a tumoração óssea. Os tratamentos cirúrgicos simultâneos de ambas as lesões foram realizados com boa evolução pós-operatória.Osteochondromas or exostoses are the most common benign tumors of the bone. They occur during the growth period and are rarely responsible for vascular complications. We report a case of a patient with osteochondroma in the lower limb and vascular complication caused by compression of the popliteal artery. The patient complained of pain at the right lower limb during angiography and radiography screening, which identified the vascular lesion and the bone tumor. A simultaneous surgical treatment of both lesions was performed with good postoperative evolution.

Effect of electroacupuncture on the expression of mTOR and eIF4E in hippocampus of rats with vascular dementia.

Science.gov (United States)

Zhu, Yanzhen; Zeng, Yanjun; Wang, Xuan; Ye, Xiaobao

2013-07-01

Clinically, electroacupuncture is proved to be an effective therapy for vascular dementia; however, their mechanisms remain uncertain. The aim of the current study was to investigate the mechanism of electroacupuncture therapy for vascular dementia. One month after a vascular dementia animal model was established by bilateral occlusion of common carotid arteries, electroacupuncture treatment was given at "Baihui" (DU20), "Dazhui" (DU14), and "Shenshu" (BL23). Morris water maze was used to assess the learning and memory ability of rats. Western blot assay was performed to detect the expression of mammalian target of rapamycin (mTOR) and eukaryotic translation initiation factor 4E (eIF4E) in hippocampus of rats. Morris water maze test showed that electroacupuncture improved the learning ability of vascular dementia rats. Western blot assay revealed that the expression level of mTOR and eIF4E in the electroacupuncture group and sham-operated group was higher than that in the vascular dementia group (P Electroacupuncture improves learning and memory ability by up-regulating expression of mTOR and eIF4E in the hippocampus of vascular dementia rats.

Vascular retraction driven by matrix softening

Science.gov (United States)

Valentine, Megan

We recently discovered we can directly apply physical forces and monitor the downstream responses in a living organism in real time through manipulation of the blood vessels of a marine organism called, Botryllus schlosseri. The extracellular matrix (ECM) plays a key role in regulating vascular growth and homeostasis in Botryllus,a basal chordate which has a large, transparent extracorporeal vascular network that can encompass areas >100 cm2. We have determined that lysyl oxidase 1 (LOX1), which is responsible for cross-linking collagen, is expressed in all vascular cells and is critically important for vascular maintenance. Inhibition of LOX1 activity in vivo by the addition of a specific inhibitor, ß-aminopropionitrile (BAPN), caused a rapid, global regression of the entire vascular bed, with some vessels regressing >10 mm within 16 hrs. In this talk, I will discuss the molecular and cellular origins of this systemic remodeling event, which hinges upon the ability of the vascular cells to sense and respond to mechanical signals, while introducing this exciting new model system for studies of biological physics and mechanobiology. Collaborators: Anthony DeTomaso, Delany Rodriguez, Aimal Khankhel (UCSB).

Effects of ouabain on vascular reactivity

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Vassallo D.V.

1997-04-01

Full Text Available Ouabain is an endogenous substance occurring in the plasma in the nanomolar range, that has been proposed to increase vascular resistance and induce hypertension. This substance acts on the a-subunit of Na+,K+-ATPase inhibiting the Na+-pump activity. In the vascular smooth muscle this effect leads to intracellular Na+ accumulation that reduces the activity of the Na+/Ca2+ exchanger and to an increased vascular tone. It was also suggested that circulating ouabain, even in the nanomolar range, sensitizes the vascular smooth muscle to vasopressor substances. We tested the latter hypothesis by studying the effects of ouabain in the micromolar and nanomolar range on phenylephrine (PE-evoked pressor responses. The experiments were performed in normotensive and hypertensive rats in vivo, under anesthesia, and in perfused rat tail vascular beds. The results showed that ouabain pretreatment increased the vasopressor responses to PE in vitro and in vivo. This sensitization after ouabain treatment was also observed in hypertensive animals which presented an enhanced vasopressor response to PE in comparison to normotensive animals. It is suggested that ouabain at nanomolar concentrations can sensitize vascular smooth muscle to vasopressor stimuli possibly contributing to increased tone in hypertension

Frequency dependent loss analysis and minimization of system losses in switchmode audio power amplifiers

DEFF Research Database (Denmark)

Yamauchi, Akira; Knott, Arnold; Jørgensen, Ivan Harald Holger

2014-01-01

In this paper, frequency dependent losses in switch-mode audio power amplifiers are analyzed and a loss model is improved by taking the voltage dependence of the parasitic capacitance of MOSFETs into account. The estimated power losses are compared to the measurement and great accuracy is achieved...

LRP1 functions as an atheroprotective integrator of TGFbeta and PDFG signals in the vascular wall: implications for Marfan syndrome.

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Philippe Boucher

2007-05-01

Full Text Available The multifunctional receptor LRP1 controls expression, activity and trafficking of the PDGF receptor-beta in vascular smooth muscle cells (VSMC. LRP1 is also a receptor for TGFbeta1 and is required for TGFbeta mediated inhibition of cell proliferation.We show that loss of LRP1 in VSMC (smLRP(- in vivo results in a Marfan-like syndrome with nuclear accumulation of phosphorylated Smad2/3, disruption of elastic layers, tortuous aorta, and increased expression of the TGFbeta target genes thrombospondin-1 (TSP1 and PDGFRbeta in the vascular wall. Treatment of smLRP1(- animals with the PPARgamma agonist rosiglitazone abolished nuclear pSmad accumulation, reversed the Marfan-like phenotype, and markedly reduced smooth muscle proliferation, fibrosis and atherosclerosis independent of plasma cholesterol levels.Our findings are consistent with an activation of TGFbeta signals in the LRP1-deficient vascular wall. LRP1 may function as an integrator of proliferative and anti-proliferative signals that control physiological mechanisms common to the pathogenesis of Marfan syndrome and atherosclerosis, and this is essential for maintaining vascular wall integrity.

Metabolic and vascular effects of tumor necrosis factor-alpha blockade with etanercept in obese patients with type 2 diabetes

DEFF Research Database (Denmark)

Dominguez, Helena; Storgaard, Heidi; Rask-Madsen, Christian

2005-01-01

OBJECTIVE: The pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) impairs insulin action in insulin-sensitive tissues, such as fat, muscle and endothelium, and causes endothelial dysfunction. We hypothesized that TNF-alpha blockade with etanercept could reverse vascular and metabolic...... glucose uptake remained unchanged as well. Beta-cell function tended to improve. CONCLUSION: Although short-term etanercept treatment had a significant beneficial effect on systemic inflammatory markers, no improvement of vascular or metabolic insulin sensitivity was observed....

Vascular endothelial growth factor receptor-3 is a novel target to improve net ultrafiltration in methylglyoxal-induced peritoneal injury.

Science.gov (United States)

Terabayashi, Takeshi; Ito, Yasuhiko; Mizuno, Masashi; Suzuki, Yasuhiro; Kinashi, Hiroshi; Sakata, Fumiko; Tomita, Takako; Iguchi, Daiki; Tawada, Mitsuhiro; Nishio, Ryosuke; Maruyama, Shoichi; Imai, Enyu; Matsuo, Seiichi; Takei, Yoshifumi

2015-09-01

Appropriate fluid balance is important for good clinical outcomes and survival in patients on peritoneal dialysis. We recently reported that lymphangiogenesis associated with fibrosis developed in the peritoneal cavity via the transforming growth factor-β1-vascular endothelial growth factor-C (VEGF-C) pathway. We investigated whether VEGF receptor-3 (VEGFR-3), the receptor for VEGF-C and -D, might be a new target to improve net ultrafiltration by using adenovirus-expressing soluble VEGFR-3 (Adeno-sVEGFR-3) in rodent models of peritoneal injury induced by methylglyoxal (MGO). We demonstrated that lymphangiogenesis developed in these MGO models, especially in the diaphragm, indicating that lymphangiogenesis is a common feature in the peritoneal cavity with inflammation and fibrosis. In MGO models, VEGF-D was significantly increased in the diaphragm; however, VEGF-C was not significantly upregulated. Adeno-sVEGFR-3, which was detected on day 50 after administration via tail vein injections, successfully suppressed lymphangiogenesis in the diaphragm and parietal peritoneum in mouse MGO models without significant effects on fibrosis, inflammation, or neoangiogenesis. Drained volume in the peritoneal equilibration test using a 7.5% icodextrin peritoneal dialysis solution (the 7.5% icodextrin peritoneal equilibration test) was improved by Adeno-sVEGFR-3 on day 22 (Ptarget to improve net ultrafiltration by suppressing lymphatic absorption and that the 7.5% icodextrin peritoneal equilibration test is useful for estimation of lymphatic absorption.

Vascular Response of the Segments Adjacent to the Proximal and Distal Edges of the ABSORB Everolimus-Eluting Bioresorbable Vascular Scaffold

DEFF Research Database (Denmark)

Gogas, Bill D; Serruys, Patrick W; Diletti, Roberto

2012-01-01

This study sought to investigate in vivo the vascular response at the proximal and distal edges of the second-generation ABSORB everolimus-eluting bioresorbable vascular scaffold (BVS).......This study sought to investigate in vivo the vascular response at the proximal and distal edges of the second-generation ABSORB everolimus-eluting bioresorbable vascular scaffold (BVS)....

Improving patient access to prevent sight loss: ophthalmic electronic referrals and communication (Scotland).

Science.gov (United States)

Khan, A A; Mustafa, M Z; Sanders, R

2015-02-01

With the number of people with sight loss predicted to double to four million people in the UK by the year 2050, preventable visual loss is a significant public health issue. Sight loss is associated with an increased risk of falls, accidents and depression and evidence suggests that 50% of sight loss can be avoided. Timely diagnosis is central to the prevention of sight loss. Access to care can be a limiting factor in preventable cases. By improving referrals and access to hospital eye services it is possible to treat and minimise the number of patients with preventable sight loss and the impact this has on wider society. In 2005, NHS Fife took part in a flagship pilot funded by the Scottish government e-health department to evaluate the feasibility, safety, clinical effectiveness, and cost of electronic referral with images of patients directly from community optometrists to Hospital Eye Service (HES). The pilot study showed that electronic referral was feasible, fast, safe, and obviated the need for outpatient appointments in 128 (37%) patients with a high patient satisfaction. The results of the pilot study were presented and in May 2007, the electronic referral system was rolled out regionally in southeast Scotland. Referrals were accepted at a single site with vetting by a trained team and appointments were allocated within 48 hours. Following the implementation of electronic referral, waiting times were reduced from a median of 14 to 4 weeks. Significantly fewer new patients were seen (7462 vs 8714 [p electronic communication between community optometry practices and hospital eye departments. Five electronic forms were specifically designed for cataract, glaucoma, macula, paediatric and general ophthalmic disease. A Virtual Private Network was created which enabled optometrists to connect to the Scottish clinical information gateway system and send referrals to hospital and receive referral status feedback. Numerous hurdles have been encountered and overcome

Detection of vascularity in wrist tenosynovitis: power doppler ultrasound compared with contrast-enhanced grey-scale ultrasound.

Science.gov (United States)

Klauser, Andrea S; Franz, Magdalena; Arora, Rohit; Feuchtner, Gudrun M; Gruber, Johann; Schirmer, Michael; Jaschke, Werner R; Gabl, Markus F

2010-01-01

We sought to assess vascularity in wrist tenosynovitis by using power Doppler ultrasound (PDUS) and to compare detection of intra- and peritendinous vascularity with that of contrast-enhanced grey-scale ultrasound (CEUS). Twenty-six tendons of 24 patients (nine men, 15 women; mean age ± SD, 54.4 ± 11.8 years) with a clinical diagnosis of tenosynovitis were examined with B-mode ultrasonography, PDUS, and CEUS by using a second-generation contrast agent, SonoVue (Bracco Diagnostics, Milan, Italy) and a low-mechanical-index ultrasound technique. Thickness of synovitis, extent of vascularized pannus, intensity of peritendinous vascularisation, and detection of intratendinous vessels was incorporated in a 3-score grading system (grade 0 to 2). Interobserver variability was calculated. With CEUS, a significantly greater extent of vascularity could be detected than by using PDUS (P < 0.001). In terms of peri- and intratendinous vessels, CEUS was significantly more sensitive in the detection of vascularization compared with PDUS (P < 0.001). No significant correlation between synovial thickening and extent of vascularity could be found (P = 0.089 to 0.097). Interobserver reliability was calculated to be excellent when evaluating the grading score (κ = 0.811 to 1.00). CEUS is a promising tool to detect tendon vascularity with higher sensitivity than PDUS by improved detection of intra- and peritendinous vascularity.

Modular tissue engineering for the vascularization of subcutaneously transplanted pancreatic islets.

Science.gov (United States)

Vlahos, Alexander E; Cober, Nicholas; Sefton, Michael V

2017-08-29

The transplantation of pancreatic islets, following the Edmonton Protocol, is a promising treatment for type I diabetics. However, the need for multiple donors to achieve insulin independence reflects the large loss of islets that occurs when islets are infused into the portal vein. Finding a less hostile transplantation site that is both minimally invasive and able to support a large transplant volume is necessary to advance this approach. Although the s.c. site satisfies both these criteria, the site is poorly vascularized, precluding its utility. To address this problem, we demonstrate that modular tissue engineering results in an s.c. vascularized bed that enables the transplantation of pancreatic islets. In streptozotocin-induced diabetic SCID/beige mice, the injection of 750 rat islet equivalents embedded in endothelialized collagen modules was sufficient to restore and maintain normoglycemia for 21 days; the same number of free islets was unable to affect glucose levels. Furthermore, using CLARITY, we showed that embedded islets became revascularized and integrated with the host's vasculature, a feature not seen in other s.c. Collagen-embedded islets drove a small (albeit not significant) shift toward a proangiogenic CD206 + MHCII - (M2-like) macrophage response, which was a feature of module-associated vascularization. While these results open the potential for using s.c. islet delivery as a treatment option for type I diabetes, the more immediate benefit may be for the exploration of revascularized islet biology.

Melatonin Decreases Pulmonary Vascular Remodeling and Oxygen Sensitivity in Pulmonary Hypertensive Newborn Lambs

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Cristian R. Astorga

2018-03-01

Full Text Available Background: Chronic hypoxia and oxidative stress during gestation lead to pulmonary hypertension of the neonate (PHN, a condition characterized by abnormal pulmonary arterial reactivity and remodeling. Melatonin has strong antioxidant properties and improves pulmonary vascular function. Here, we aimed to study the effects of melatonin on the function and structure of pulmonary arteries from PHN lambs.Methods: Twelve lambs (Ovis aries gestated and born at highlands (3,600 m were instrumented with systemic and pulmonary catheters. Six of them were assigned to the control group (CN, oral vehicle and 6 were treated with melatonin (MN, 1 mg.kg−1.d−1 during 10 days. At the end of treatment, we performed a graded oxygenation protocol to assess cardiopulmonary responses to inspired oxygen variations. Further, we obtained lung and pulmonary trunk samples for histology, molecular biology, and immunohistochemistry determinations.Results: Melatonin reduced the in vivo pulmonary pressor response to oxygenation changes. In addition, melatonin decreased cellular density of the media and diminished the proliferation marker KI67 in resistance vessels and pulmonary trunk (p < 0.05. This was associated with a decreased in the remodeling markers α-actin (CN 1.28 ± 0.18 vs. MN 0.77 ± 0.04, p < 0.05 and smoothelin-B (CN 2.13 ± 0.31 vs. MN 0.88 ± 0.27, p < 0.05. Further, melatonin increased vascular density by 134% and vascular luminal surface by 173% (p < 0.05. Finally, melatonin decreased nitrotyrosine, an oxidative stress marker, in small pulmonary vessels (CN 5.12 ± 0.84 vs. MN 1.14 ± 0.34, p < 0.05.Conclusion: Postnatal administration of melatonin blunts the cardiopulmonary response to hypoxia, reduces the pathological vascular remodeling, and increases angiogenesis in pulmonary hypertensive neonatal lambs.These effects improve the pulmonary vascular structure and function in the neonatal period under chronic hypoxia.

Melatonin Decreases Pulmonary Vascular Remodeling and Oxygen Sensitivity in Pulmonary Hypertensive Newborn Lambs

Science.gov (United States)

Astorga, Cristian R.; González-Candia, Alejandro; Candia, Alejandro A.; Figueroa, Esteban G.; Cañas, Daniel; Ebensperger, Germán; Reyes, Roberto V.; Llanos, Aníbal J.; Herrera, Emilio A.

2018-01-01

Background: Chronic hypoxia and oxidative stress during gestation lead to pulmonary hypertension of the neonate (PHN), a condition characterized by abnormal pulmonary arterial reactivity and remodeling. Melatonin has strong antioxidant properties and improves pulmonary vascular function. Here, we aimed to study the effects of melatonin on the function and structure of pulmonary arteries from PHN lambs. Methods: Twelve lambs (Ovis aries) gestated and born at highlands (3,600 m) were instrumented with systemic and pulmonary catheters. Six of them were assigned to the control group (CN, oral vehicle) and 6 were treated with melatonin (MN, 1 mg.kg−1.d−1) during 10 days. At the end of treatment, we performed a graded oxygenation protocol to assess cardiopulmonary responses to inspired oxygen variations. Further, we obtained lung and pulmonary trunk samples for histology, molecular biology, and immunohistochemistry determinations. Results: Melatonin reduced the in vivo pulmonary pressor response to oxygenation changes. In addition, melatonin decreased cellular density of the media and diminished the proliferation marker KI67 in resistance vessels and pulmonary trunk (p < 0.05). This was associated with a decreased in the remodeling markers α-actin (CN 1.28 ± 0.18 vs. MN 0.77 ± 0.04, p < 0.05) and smoothelin-B (CN 2.13 ± 0.31 vs. MN 0.88 ± 0.27, p < 0.05). Further, melatonin increased vascular density by 134% and vascular luminal surface by 173% (p < 0.05). Finally, melatonin decreased nitrotyrosine, an oxidative stress marker, in small pulmonary vessels (CN 5.12 ± 0.84 vs. MN 1.14 ± 0.34, p < 0.05). Conclusion: Postnatal administration of melatonin blunts the cardiopulmonary response to hypoxia, reduces the pathological vascular remodeling, and increases angiogenesis in pulmonary hypertensive neonatal lambs.These effects improve the pulmonary vascular structure and function in the neonatal period under chronic hypoxia. PMID:29559926

Vascular Contributions to Cognitive Impairment and Dementia

Science.gov (United States)

Gorelick, Philip B.; Scuteri, Angelo; Black, Sandra E.; DeCarli, Charles; Greenberg, Steven M.; Iadecola, Costantino; Launer, Lenore J.; Laurent, Stephane; Lopez, Oscar L.; Nyenhuis, David; Petersen, Ronald C.; Schneider, Julie A.; Tzourio, Christophe; Arnett, Donna K.; Bennett, David A.; Chui, Helena C.; Higashida, Randall T.; Lindquist, Ruth; Nilsson, Peter M.; Roman, Gustavo C.; Sellke, Frank W.; Seshadri, Sudha

2013-01-01

, clinical-pathological-neuroimaging studies to improve knowledge of the pathological basis of neuroimaging change and the complex interplay between vascular and Alzheimer disease pathologies in the evolution of clinical VCI and Alzheimer disease. Long-term vascular risk marker interventional studies beginning as early as midlife may be required to prevent or postpone the onset of VCI and Alzheimer disease. Studies of intensive reduction of vascular risk factors in high-risk groups are another important avenue of research. PMID:21778438

Advanced Coats’ disease treated with intravitreal bevacizumab combined with laser vascular ablation

Directory of Open Access Journals (Sweden)

Villegas VM

2014-05-01

Full Text Available Victor M Villegas,1 Aaron S Gold,1 Audina M Berrocal,2 Timothy G Murray11Ocular Oncology and Retina, Miami, FL, USA; 2Department of Ophthalmology, Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, FL, USAPurpose: To evaluate the impact of intravitreal bevacizumab combined with laser vascular ablation in the management of advanced Coats’ disease presenting with exudative retinal detachment.Methods: This was a retrospective review of 24 children that presented with exudative retinal detachments associated with advanced Coats’ disease. Mean patient age was 62 months (range 9–160 months. Presenting signs included retinal detachment in 24 children (100%, vascular telangiectasia in 24 children (100%, and retinal ischemia in 24 children (100%. Twenty of 24 children presented with elevated, vascular leakage in the fovea (83%. Two children presented with sub-retinal fibrosis associated with presumed long-standing retinal detachment without evidence of rhegmatogenous retinal detachment. Ten patients exhibited vascular alterations in the periphery of the second eye without clinical evidence of exudation. All 24 children were treated with a large-spot-size diode laser directly to areas of abnormal telangiectatic vasculature. All 24 children received intravitreal bevacizumab injection. Results: All 24 children had resolution of exudative retinal detachment, ablation of vascular telangiectasia, and anatomic improvement of the retina. No child exhibited progressive retinal detachment and no eye required enucleation. No cases of neovascular glaucoma were seen. Fellow eyes with peripheral vascular alterations showed no progression to exudative vasculopathy during the observation period. Intravitreal bevacizumab injection was not associated with endophthalmitis or systemically-observed complications.Conclusion: Repetitive intravitreal bevacizumab combined with laser vascular ablation may be utilized effectively

CIRSE Vascular Closure Device Registry

NARCIS (Netherlands)

Reekers, Jim A.; Müller-Hülsbeck, Stefan; Libicher, Martin; Atar, Eli; Trentmann, Jens; Goffette, Pierre; Borggrefe, Jan; Zeleňák, Kamil; Hooijboer, Pieter; Belli, Anna-Maria

2011-01-01

Vascular closure devices are routinely used after many vascular interventional radiology procedures. However, there have been no major multicenter studies to assess the safety and effectiveness of the routine use of closure devices in interventional radiology. The CIRSE registry of closure devices

The vascular secret of Klotho

DEFF Research Database (Denmark)

Lewin, Ewa; Olgaard, Klaus

2015-01-01

Klotho is an evolutionarily highly conserved protein related to longevity. Increasing evidence of a vascular protecting effect of the Klotho protein has emerged and might be important for future treatments of uremic vascular calcification. It is still disputed whether Klotho is locally expressed ...

Enhanced elastin synthesis and maturation in human vascular smooth muscle tissue derived from induced-pluripotent stem cells.

Science.gov (United States)

Eoh, Joon H; Shen, Nian; Burke, Jacqueline A; Hinderer, Svenja; Xia, Zhiyong; Schenke-Layland, Katja; Gerecht, Sharon

2017-04-01

Obtaining vascular smooth muscle tissue with mature, functional elastic fibers is a key obstacle in tissue-engineered blood vessels. Poor elastin secretion and organization leads to a loss of specialization in contractile smooth muscle cells, resulting in over proliferation and graft failure. In this study, human induced-pluripotent stem cells (hiPSCs) were differentiated into early smooth muscle cells, seeded onto a hybrid poly(ethylene glycol) dimethacrylate/poly (l-lactide) (PEGdma-PLA) scaffold and cultured in a bioreactor while exposed to pulsatile flow, towards maturation into contractile smooth muscle tissue. We evaluated the effects of pulsatile flow on cellular organization as well as elastin expression and assembly in the engineered tissue compared to a static control through immunohistochemistry, gene expression and functionality assays. We show that culturing under pulsatile flow resulted in organized and functional hiPSC derived smooth muscle tissue. Immunohistochemistry analysis revealed hiPSC-smooth muscle tissue with robust, well-organized cells and elastic fibers and the supporting microfibril proteins necessary for elastic fiber assembly. Through qRT-PCR analysis, we found significantly increased expression of elastin, fibronectin, and collagen I, indicating the synthesis of necessary extracellular matrix components. Functionality assays revealed that hiPSC-smooth muscle tissue cultured in the bioreactor had an increased calcium signaling and contraction in response to a cholinergic agonist, significantly higher mature elastin content and improved mechanical properties in comparison to the static control. The findings presented here detail an effective approach to engineering elastic human vascular smooth muscle tissue with the functionality necessary for tissue engineering and regenerative medicine applications. Obtaining robust, mature elastic fibers is a key obstacle in tissue-engineered blood vessels. Human induced-pluripotent stem cells have

Vascular Gene Expression: A Hypothesis

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Angélica Concepción eMartínez-Navarro

2013-07-01

Full Text Available The phloem is the conduit through which photoassimilates are distributed from autotrophic to heterotrophic tissues and is involved in the distribution of signaling molecules that coordinate plant growth and responses to the environment. Phloem function depends on the coordinate expression of a large array of genes. We have previously identified conserved motifs in upstream regions of the Arabidopsis genes, encoding the homologs of pumpkin phloem sap mRNAs, displaying expression in vascular tissues. This tissue-specific expression in Arabidopsis is predicted by the overrepresentation of GA/CT-rich motifs in gene promoters. In this work we have searched for common motifs in upstream regions of the homologous genes from plants considered to possess a primitive vascular tissue (a lycophyte, as well as from others that lack a true vascular tissue (a bryophyte, and finally from chlorophytes. Both lycophyte and bryophyte display motifs similar to those found in Arabidopsis with a significantly low E-value, while the chlorophytes showed either a different conserved motif or no conserved motif at all. These results suggest that these same genes are expressed coordinately in non- vascular plants; this coordinate expression may have been one of the prerequisites for the development of conducting tissues in plants. We have also analyzed the phylogeny of conserved proteins that may be involved in phloem function and development. The presence of CmPP16, APL, FT and YDA in chlorophytes suggests the recruitment of ancient regulatory networks for the development of the vascular tissue during evolution while OPS is a novel protein specific to vascular plants.

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

Science.gov (United States)

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.

Fresh frozen cadaver workshops for advanced vascular surgical training.

Science.gov (United States)

Jansen, Shirley; Cowie, Margaret; Linehan, John; Hamdorf, Jeffery M

2014-11-01

Reduction in working hours, streamlined training schemes and increasing use of endovascular techniques has meant a reduction in operative experience for newer vascular surgical trainees, especially those exposures which are not routinely performed such as thoracoabdominal, thoracotomy and retroperitoneal aortic, for example. This paper describes an Advanced Anatomy of Exposure course which was designed and convened at the Clinical Training & Evaluation Centre in Western Australia and uses fresh frozen cadavers. Feedback was obtained from the participants who attended over three courses by questionnaire. Feedback was strongly positive for the course meeting both its learning outcomes and personal learning objectives, and in addition, making a significant contribution to specialty skills. Most participants thought the fresh frozen cadaveric model significantly improved the learning objectives for training. The fresh frozen cadaver is an excellent teaching model highly representative of the living open surgical scenario where advanced trainees and newly qualified consultants can improve their operative confidence and consequently patient safety in vascular surgery. An efficient fresh frozen cadaver teaching programme can benefit many health professionals simultaneously maximizing the use of donated human tissue. © 2013 Royal Australasian College of Surgeons.

Adiposity, adipocytokines & microvesicles in the etiology of vascular disease

NARCIS (Netherlands)

Kanhai, D.A.N.I.S.

2013-01-01

Vascular disease, in this thesis the terms vascular and cardiovascular are used interchangeably, is the number 1 cause of death worldwide. In 2008, 30% of all mortality had a vascular origin. Vascular mortality rates after a first manifestation of vascular disease are decreasing in Western society,

Robust Improvement in Estimation of a Covariance Matrix in an Elliptically Contoured Distribution Respect to Quadratic Loss Function

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Z. Khodadadi

2008-03-01

Full Text Available Let S be matrix of residual sum of square in linear model Y = Aβ + e where matrix e is distributed as elliptically contoured with unknown scale matrix Σ. In present work, we consider the problem of estimating Σ with respect to squared loss function, L(Σˆ , Σ = tr(ΣΣˆ −1 −I 2 . It is shown that improvement of the estimators were obtained by James, Stein [7], Dey and Srivasan [1] under the normality assumption remains robust under an elliptically contoured distribution respect to squared loss function

Enhanced endothelial cell functions on rosette nanotube-coated titanium vascular stents

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Eli Fine

2009-04-01

Full Text Available Eli Fine1, Lijie Zhang1, Hicham Fenniri2, Thomas J Webster1 1Department of Engineering, Brown University, Providence, RI, USA; 2National Institute for Nanotechnology and Department of Chemistry, University of Alberta, Edmonton, AB, CanadaAbstract: One of the main problems with current vascular stents is a lack of endothelial cell interactions, which if sufficient, would create a uniform healthy endothelium masking the underlying foreign metal from inflammatory cell interference. Moreover, if endothelial cells from the arterial wall do not adhere to the stent, the stent can become loose and dislodge. Therefore, the objective of this in vitro study was to design a novel biomimetic nanostructured coating (that does not contain drugs on conventional vascular stent materials (specifically, titanium for improving vascular stent applications. Rosette nanotubes (RNTs are a new class of biomimetic nanotubes that self-assemble from DNA base analogs and have been shown in previous studies to sufficiently coat titanium and enhance osteoblast cell functions. RNTs have many desirable properties for use as vascular stent coatings including spontaneous self-assembly in body fluids, tailorable surface chemistry for specific implant applications, and nanoscale dimensions similar to those of the natural vascular extracellular matrix. Importantly, the results of this study provided the first evidence that RNTs functionalized with lysine (RNT–K, even at low concentrations, significantly increase endothelial cell density over uncoated titanium. Specifically, 0.01 mg/mL RNT–K coated titanium increased endothelial cell density by 37% and 52% compared to uncoated titanium after 4 h and three days, respectively. The excellent cytocompatibility properties of RNTs (as demonstrated here for the first time for endothelial cells suggest the need for the further exploration of these novel nanostructured materials for vascular stent applications.Keywords: stents

Nova técnica para treinamento em acessos vasculares guiados por ultrassom utilizando modelo de tecido animal New technique for ultrasound-guided vascular access training using an animal tissue model

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Robson Barbosa de Miranda

2012-03-01

Full Text Available A ultrassonografia Doppler deixou de ter seu uso apenas como método diagnóstico e vem galgando espaço nos procedimentos terapêuticos. Com maior aplicabilidade e uso de cateteres venosos centrais e procedimentos guiados por ultrassom, há preocupação com a melhora da eficácia e segurança durante o procedimento, assim como com a diminuição das potenciais complicações. Para isso, o treinamento da técnica em modelos (phantoms é desejável. Os modelos industrializados para treinamento em acesso vascular guiado por ultrassom são caros e não reproduzem adequadamente a ecotextura e a densidade dos tecidos humanos. Na tentativa de treinar e aprimorar os profissionais para o uso do ultrassom em procedimentos de acessos vasculares, desenvolveu-se um modelo animal de baixo custo, fácil confecção e excelente aplicabilidade.Duplex ultrasonography has not been used only as a noninvasive diagnostic method. Recently it has been applied for therapeutic procedures. Due to the increasing use and applicability of central venous catheters and eco-guided vascular procedures, there are concerns about improving results regarding accuracy and safety, reducing complication rates during those procedures. It would be desirable that training was accomplished using phantoms before actual procedures in human subjects. Industrialized phantoms are expensive and they do not reproduce human's ecographic density and texture. In order to train and improve ultrasound guided vascular access, we have developed a cheap animal tissue model, which is of easy preparation and applicability.

Emergent endovascular embolization of iatrogenic renal vascular injuries

International Nuclear Information System (INIS)

Liu Fengyong; Wang Maoqiang; Duan Feng; Wang Zhijun; Wang Zhongpu

2007-01-01

Objective: To evaluate the efficacy and safety of the interventional techniques for emergent treatment of iatrogenic renal injuries. Methods: Nine patients with iatrogenic renal vascular injuries were treated with superselective renal arterial embolization. The causes of renal injury included post-renal biopsy in 5 patients, endovascular interventional procedure-related in 2, post-renal surgery in 1, and post-percutaneous nephrostomy in 1 patient. The patients presented clinically with hemodynamical unstability with blood loss shock in 7 patients, severe flank pain in 7, and hematuria in 8 patients. Perirenal hematoma was confirmed in 8 patients by CT and ultrasonography. The embolization materials used were microcoils in 7 and standard stainless steel coils in 2 patients, associated with polyvinyl alcohol particles (PVA) in 5, and gelfoam particles in 2 cases. Results: Renal angiogram revealed intra-renal arteriovenous fistula in 6 cases, intrarenal pseudoaneurysm in 2 cases, and the contrast media extravasation in 1 patient. The technical success of the arterial embolization was achieved in all 9 cases within a single session. All angiographies documented complete obliteration of the abnormal vessels together with all major intrarenal arterial branches maintaining patent. Seven patients with hemodynamically compromise experienced immediate relief of their blood loss related symptoms, and another 7 with severe flank pain got relief progressively.. Hematuria ceased in 8 patients within 2-14 days after the embolization and impairment of renal function occurred after the procedure in 5 cases, including transient aggravation (n=3 )and developed new renal dysfunction (n=2). Two of these patients required hemodialysis. Perirenal hematoma were gradually absorbed on ultrasonography during 2-4 months after the procedures. Follow-up time ranged from 6-78 months (mean, 38 months), 4 patients died of other primary diseases of renal and multi-organ failures. Five patients are

Three-dimensional bioprinting of thick vascularized tissues

Science.gov (United States)

Kolesky, David B.; Homan, Kimberly A.; Skylar-Scott, Mark A.; Lewis, Jennifer A.

2016-03-01

The advancement of tissue and, ultimately, organ engineering requires the ability to pattern human tissues composed of cells, extracellular matrix, and vasculature with controlled microenvironments that can be sustained over prolonged time periods. To date, bioprinting methods have yielded thin tissues that only survive for short durations. To improve their physiological relevance, we report a method for bioprinting 3D cell-laden, vascularized tissues that exceed 1 cm in thickness and can be perfused on chip for long time periods (>6 wk). Specifically, we integrate parenchyma, stroma, and endothelium into a single thick tissue by coprinting multiple inks composed of human mesenchymal stem cells (hMSCs) and human neonatal dermal fibroblasts (hNDFs) within a customized extracellular matrix alongside embedded vasculature, which is subsequently lined with human umbilical vein endothelial cells (HUVECs). These thick vascularized tissues are actively perfused with growth factors to differentiate hMSCs toward an osteogenic lineage in situ. This longitudinal study of emergent biological phenomena in complex microenvironments represents a foundational step in human tissue generation.

Dynamic adaption of vascular morphology

DEFF Research Database (Denmark)

Okkels, Fridolin; Jacobsen, Jens Christian Brings

2012-01-01

The structure of vascular networks adapts continuously to meet changes in demand of the surrounding tissue. Most of the known vascular adaptation mechanisms are based on local reactions to local stimuli such as pressure and flow, which in turn reflects influence from the surrounding tissue. Here ...

Dynamics of nephron-vascular network

DEFF Research Database (Denmark)

Postnov, Dmitry; Postnov, D E; Marsh, D J

2012-01-01

The paper presents a modeling study of the spatial dynamics of a nephro-vascular network consisting of individual nephrons connected via a tree-like vascular branching structure. We focus on the effects of nonlinear mechanisms that are responsible for the formation of synchronous patterns in order...

Diagnostic criteria for vascular dementia

NARCIS (Netherlands)

Scheltens, P.; Hijdra, A. H.

1998-01-01

The term vascular dementia implies the presence of a clinical syndrome (dementia) caused by, or at least assumed to be caused by, a specific disorder (cerebrovascular disease). In this review, the various sets of criteria used to define vascular dementia are outlined. The various sets of criteria

Weight-loss changes PPAR expression, reduces atherosclerosis and improves cardiovascular function in obese insulin-resistant mice

Energy Technology Data Exchange (ETDEWEB)

Verreth, Wim; Verhamme, Peter; Pelat, Michael; Ganame, Javier; Bielicki, John K.; Mertens, Ann; Quarck, Rozenn; Benhabiles, Nora; Marguerie, Gerard; Mackness, Bharti; Mackness, Mike; Ninio, Ewa; Herregods, Marie-Christine; Balligand, Jean-Luc; Holvoet, Paul

2003-09-01

Weight-loss in obese insulin-resistant, but not in insulin-sensitive, persons reduces CHD risk. It is not known to what extent changes in the adipose gene expression profile are important for reducing CHD risk. We studied the effect of diet restriction-induced weight-loss on gene expression in adipose tissue, atherosclerosis and cardiovascular function in mice with combined leptin and LDL-receptor deficiency. Obesity, hypertriglyceridemia and insulin-resistance are associated with hypertension, impaired left ventricle function and accelerated atherosclerosis in those mice. Diet restriction during 12 weeks caused a 45% weight-loss and changes in the gene expression in adipose tissue of PPARa and PPAR? and of key genes regulating glucose transport and insulin sensitivity, lipid metabolism, oxidative stress and inflammation, most of which are under the transcriptional control of PPARs. These changes were associated with increased insulin-sensitivity, decreased hypertriglyceridemia, reduced mean 24-hour blood pressure and heart rate, restored circadian variations of blood pressure and heart rate, increased ejection fraction, and reduced atherosclerosis. Thus, induction of PPARa and PPAR? in adipose tissue is a key mechanism for reducing atherosclerosis and improving cardiovascular function resulting from weight-loss. Our observations point to the critical role of PPARs in the pathogenesis of cardiovascular features of the metabolic syndrome.

Vascular corrosion casting of normal and pre-eclamptic placentas.

Science.gov (United States)

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.

Vascular ATP-sensitive potassium channels are over-expressed and partially regulated by nitric oxide in experimental septic shock.

Science.gov (United States)

Collin, Solène; Sennoun, Nacira; Dron, Anne-Gaëlle; de la Bourdonnaye, Mathilde; Montemont, Chantal; Asfar, Pierre; Lacolley, Patrick; Meziani, Ferhat; Levy, Bruno

2011-05-01

To study the activation and expression of vascular (aorta and small mesenteric arteries) potassium channels during septic shock with or without modulation of the NO pathway. Septic shock was induced in rats by peritonitis. Selective inhibitors of vascular K(ATP) (PNU-37883A) or BK(Ca) [iberiotoxin (IbTX)] channels were used to demonstrate their involvement in vascular hyporeactivity. Vascular response to phenylephrine was measured on aorta and small mesenteric arteries mounted on a wire myograph. Vascular expression of potassium channels was studied by PCR and Western blot, in the presence or absence of 1400W, an inducible NO synthase (iNOS) inhibitor. Aortic activation of the transcriptional factor nuclear factor-kappaB (NF-κB) was assessed by electrophoretic mobility shift assay. Arterial pressure as well as in vivo and ex vivo vascular reactivity were reduced by sepsis and improved by PNU-37883A but not by IbTX. Sepsis was associated with an up-regulation of mRNA and protein expression of vascular K(ATP) channels, while expression of vascular BK(Ca) channels remained unchanged. Selective iNOS inhibition blunted the sepsis-induced increase in aortic NO, decreased NF-κB activation, and down-regulated vascular K(ATP) channel expression. Vascular K(ATP) but not BK(Ca) channels are activated, over-expressed, and partially regulated by NO via NF-κB activation during septic shock. Their selective inhibition restores arterial pressure and vascular reactivity and decreases lactate concentration. The present data suggest that selective vascular K(ATP) channel inhibitors offer potential therapeutic perspectives for septic shock.

3D bioprinting for vascularized tissue fabrication

Science.gov (United States)

Richards, Dylan; Jia, Jia; Yost, Michael; Markwald, Roger; Mei, Ying

2016-01-01

3D bioprinting holds remarkable promise for rapid fabrication of 3D tissue engineering constructs. Given its scalability, reproducibility, and precise multi-dimensional control that traditional fabrication methods do not provide, 3D bioprinting provides a powerful means to address one of the major challenges in tissue engineering: vascularization. Moderate success of current tissue engineering strategies have been attributed to the current inability to fabricate thick tissue engineering constructs that contain endogenous, engineered vasculature or nutrient channels that can integrate with the host tissue. Successful fabrication of a vascularized tissue construct requires synergy between high throughput, high-resolution bioprinting of larger perfusable channels and instructive bioink that promotes angiogenic sprouting and neovascularization. This review aims to cover the recent progress in the field of 3D bioprinting of vascularized tissues. It will cover the methods of bioprinting vascularized constructs, bioink for vascularization, and perspectives on recent innovations in 3D printing and biomaterials for the next generation of 3D bioprinting for vascularized tissue fabrication. PMID:27230253

Progenitor cells in pulmonary vascular remodeling

Science.gov (United States)

Yeager, Michael E.; Frid, Maria G.; Stenmark, Kurt R.

2011-01-01

Pulmonary hypertension is characterized by cellular and structural changes in the walls of pulmonary arteries. Intimal thickening and fibrosis, medial hypertrophy and fibroproliferative changes in the adventitia are commonly observed, as is the extension of smooth muscle into the previously non-muscularized vessels. A majority of these changes are associated with the enhanced presence of α-SM-actin+ cells and inflammatory cells. Atypical abundances of functionally distinct endothelial cells, particularly in the intima (plexiform lesions), and also in the perivascular regions, are also described. At present, neither the origin(s) of these cells nor the molecular mechanisms responsible for their accumulation, in any of the three compartments of the vessel wall, have been fully elucidated. The possibility that they arise from either resident vascular progenitors or bone marrow–derived progenitor cells is now well established. Resident vascular progenitor cells have been demonstrated to exist within the vessel wall, and in response to certain stimuli, to expand and express myofibroblastic, endothelial or even hematopoietic markers. Bone marrow–derived or circulating progenitor cells have also been shown to be recruited to sites of vascular injury and to assume both endothelial and SM-like phenotypes. Here, we review the data supporting the contributory role of vascular progenitors (including endothelial progenitor cells, smooth muscle progenitor cells, pericytes, and fibrocytes) in vascular remodeling. A more complete understanding of the processes by which progenitor cells modulate pulmonary vascular remodeling will undoubtedly herald a renaissance of therapies extending beyond the control of vascular tonicity and reduction of pulmonary artery pressure. PMID:22034593

Congenital vascular malformations in scintigraphic evaluation

International Nuclear Information System (INIS)

Pilecki, Stanisław; Gierach, Marcin; Gierach, Joanna; Świętaszczyk, Cyprian; Junik, Roman; Lasek, Władysław

2014-01-01

Congenital vascular malformations are tumour-like, non-neoplastic lesions caused by disorders of vascular tissue morphogenesis. They are characterised by a normal cell replacement cycle throughout all growth phases and do not undergo spontaneous involution. Here we present a scintigraphic image of familial congenital vascular malformations in two sisters. A 17-years-old young woman with a history of multiple hospitalisations for foci of vascular anomalies appearing progressively in the upper and lower right limbs, chest wall and spleen. A Parkes Weber syndrome was diagnosed based on the clinical picture. Due to the occurrence of new foci of malformations, a whole-body scintigraphic examination was performed. A 12-years-old girl reported a lump in the right lower limb present for approximately 2 years, which was clinically identified as a vascular lesion in the area of calcaneus and talus. Phleboscintigraphy visualized normal radiomarker outflow from the feet via the deep venous system, also observed in the superficial venous system once the tourniquets were released. In static and whole-body examinations vascular malformations were visualised in the area of the medial cuneiform, navicular and talus bones of the left foot, as well as in the projection of right calcaneus and above the right talocrural joint. People with undiagnosed disorders related to the presence of vascular malformations should undergo periodic follow-up to identify lesions that may be the cause of potentially serious complications and to assess the results of treatment. Presented scintigraphic methods may be used for both diagnosing and monitoring of disease progression