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Muscular Arteries (muscular + artery)
Selected AbstractsClinical methods for the evaluation of endothelial function , a focus on resistance arteriesFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2006Robinson Joannides Abstract Endothelial dysfunction is a key event in the pathophysiology of cardiovascular diseases and appears as a strong independent predictor of cardiovascular events. In this context, biological evaluation of endothelial circulating markers can be helpful. However, functional tests using pharmacological stimuli appear more specific for the study of resistance arteries. These methods consist in the evaluation of the endothelium-dependent changes in regional vascular flow in response to local infusion of substances that act through endothelial receptors without modification of systemic arterial pressure and in comparison with a non endothelium-dependent relaxation. Flow is measured by Doppler and intravascular ultrasound in coronary circulation, laser Doppler in skin and by venous occlusion plethysmography in peripheral muscular arteries. Similar studies can be performed ex vivo using isolated resistance arteries obtained from fat subcutaneous biopsies. In addition, other information can be obtained from reactive hyperemia and the study of the flow-mediated dilatation of conduit arteries to enable a selective and comprehensive approach of the heterogeneity of endothelial function in pathophysiology. [source] Highly accelerated first-pass contrast-enhanced magnetic resonance angiography of the peripheral vasculature: Comparison of gadofosveset trisodium with gadopentetate dimeglumine contrast agentsJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2009Jeffrey H. Maki MD Abstract Purpose: To investigate the blood pool agent gadofosveset trisodium for first-pass, dynamic peripheral contrast-enhanced magnetic resonance angiography (pMRA), and compare the results with a conventional gadolinium contrast agent. Materials and Methods: A total of 16 patients were imaged at 1.5T using a prototype peripheral vascular coil with high SENSE acceleration. Five received gadopentetate dimeglumine (,0.25 mmol/kg), and 11 received gadofosveset trisodium (five standard-dose 0.03 mmol/kg, six high-dose 0.05 mmol/kg). Quantitative contrast-enhancement and qualitative image quality evaluation was compared between agents and doses. Results: High-quality diagnostic images were uniformly obtained. The contrast ratio did not significantly differ between gadopentetate dimeglumine and high-dose gadofosveset trisodium, both of which were greater than standard-dose gadofosveset trisodium. High-dose gadofosveset trisodium was equivalent to gadopentetate dimeglumine in image quality and subjective vessel-to-background ratio, but significantly better for depicting small muscular arteries. Standard-dose gadofosveset trisodium showed equivalent image quality and small artery depiction with a slight but significant decrease in vessel-to-background ratio as compared to gadopentatate dimeglumine. Both gadofosveset trisodium doses trended toward more venous enhancement, but this was not a diagnostic problem. Conclusion: First-pass peripheral CE-MRA using gadofosveset trisodium is feasible, yielding image quality comparable to double to triple-dose gadopentetate dimeglumine. Increasing the gadofosveset trisodium dose to 0.05 mmol/kg yields further improvements. J. Magn. Reson. Imaging 2009;30:1085,1092. © 2009 Wiley-Liss, Inc. [source] Arteriopathy in chronic allograft rejection in liver transplantationLIVER TRANSPLANTATION, Issue 4 2004Aya Miyagawa-Hayashino Chronic rejection is an important cause of liver allograft failures. The allograft undergoing chronic rejection shows affected large- and medium-sized muscular arteries with homing of foamy macrophages and enlargement of the intimal area. The objective of this study was to elucidate the pathogenesis of the intimal lesion that causes obliterative arteriopathy by identifying the origin of the foamy macrophages and mesenchymal cells present in the intimal area. Nine allografted livers (6 male and 3 female patients) from sex-mismatched donors undergoing chronic rejection were studied by combined staining of the macrophages or the mesenchymal cells in the intimal area with immunohistochemistry and in situ hybridization using a probe for the human Y chromosome. By using the specimens from female donor allografts transplanted to male recipients, it was found that 62 ± 11% of CD68+ foamy macrophages and 71 ± 4% of smooth muscle actin-positive mesenchymal cells in the intimal lesions and a few interstitial myofibroblasts were positive for the Y chromosome probe. This indicated that they were derived from the recipients. In conclusion, the thickening intimal lesion seen in obliterative vasculopathy in liver allografts consists of the foamy macrophages and mesenchymal cells of recipient origin. These circulating recipient cells migrated to the areas in advance of remodeling arteries. (Liver Transpl 2004;10:513,519.) [source] Cutaneous polyarteritis nodosa: A report of 16 cases with clinical and histopathological analysis and a review of the published workTHE JOURNAL OF DERMATOLOGY, Issue 1 2010Naoko ISHIGURO Abstract Sixteen cases of cutaneous polyarteritis nodosa referred to our Department from 1985 to 2003 were studied clinically and histopathologically. Laboratory data, treatments and clinical courses were also evaluated retrospectively. All cases had nodules and/or indurated erythemas on their lower extremities. All cases showed necrotizing vasculitis of small muscular arteries in the subcutaneous tissues and/or occlusion of those arteries histopathologically. Fifteen cases also had accumulation of plasma protein in vessels of the dermis and subcutaneous tissues. Laboratory data showed high activity of platelets and coagulation in some cases. Eleven cases had been effectively treated with non-steroidal anti-inflammatory drugs. Eight cases were observed for at least 5 years (the longest for ,19 years) and had good prognoses and no systemic involvement. Cutaneous polyarteritis nodosa seems to be a benign disease, and differs from systemic polyarteritis nodosa although their histopathological features are common. Cutaneous polyarteritis nodosa might involve local dysfunction of the circulation from the dermis to the subcutaneous area. A review of the published work shows that the cause(s) of most cases of cutaneous polyarteritis nodosa is unknown, that no controlled trials for treatment of cutaneous polyarteritis nodosa compared to polyarteritis nodosa have been reported, and that no definitively effective therapy for cutaneous polyarteritis nodosa has been established. [source] Compliance properties of conduits used in vascular reconstruction,BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 11 2000N. R. Tai Background Compliance mismatch between native artery and prosthetic graft used for infrainguinal bypass is implicated in the aetiology of graft failure. The aim was to quantify the elastic properties of a new compliant poly(carbonate)polyurethane (CPU) vascular graft, and to compare the compliance properties of grafts made from CPU, expanded polytetrafluoroethylene (ePTFE), Dacron and human saphenous vein with that of human muscular artery. Methods A pulsatile flow phantom was used to perfuse vessel and prosthetic graft segments at physiological pulse pressure and flow. Intraluminal pressure was measured using a Millar Mikro-tip catheter transducer and vessel wall motion was determined with duplex ultrasonography using an echo-locked wall-tracking system. Diametrical compliance and a stiffness index were then calculated for each type of conduit over mean pressures ranging from 30 to 100 mmHg by 10-mmHg increments. Results The compliance values of CPU and artery (mean over the pressure range) were similar (mean(s.d.) 8·1(0·4) and 8·0(5·9) per cent per mmHg × 10,2 respectively), although the elastic behaviour of artery was anisotropic unlike CPU, which was isotropic. Dacron and ePTFE grafts had lower compliance values (1·8(1·2) and 1·2(0·3) per cent per mmHg × 10,2 respectively, averaged over the pressure range). In both these cases, compliance and stiffness differed significantly from that of artery over a mean pressure range of 30,90 mmHg. Human saphenous vein exhibited anisotropic behaviour and, although compliant at low pressure (30 mmHg), was markedly incompliant at higher pressures. Conclusion Compliant polyurethane grafts offer a greater degree of compliance match than either ePTFE or Dacron. © 2000 British Journal of Surgery Society Ltd [source] | ||||||||||