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Understanding the molecular mechanisms that underlie the remarkable plasticity of VSMCs may lead to novel approaches to treat and prevent cardiovascular disease and restenosis.

Understanding the molecular mechanisms that underlie the remarkable plasticity of VSMCs may lead to novel approaches to treat and prevent cardiovascular disease and restenosis.Aortic aneurysms are rare manifestations in children with tuberous sclerosis complex (TSC) with life threating implications. Although an association between TSC, aortic and other aneurysms has been recognized, mechanistic insights explaining the pathophysiology behind aneurysm development and genetic aberrations in TSC have so far been lacking. Here, we summarize existing knowledge on aneurysms in TSC and present a case of a 2-year-old boy with an infrarenal aortic aneurysm, successfully treated with open aortic reconstruction. Histologic examination of the excised aneurysm wall showed distortion of vessel wall structure with loss of elastin and a pathologic accumulation of smooth muscle cells. Until now, these pathologic features have puzzled researchers as proliferating smooth muscle cells would rather be expected to preserve vessel wall integrity. Recent reports exploring the biological consequences of the dysregulated intracellular signaling pathways in patients with TSC provide plausible explanations to this paradox, which may support the development of future therapeutic strategies.

Current agents for the intravascular embolization of traumatic hemorrhage are used off-label and have been minimally studied with respect to their performance under differing coagulation conditions. Vorinostat We studied the hemorrhage control efficacy of a novel, liquid, polyethylene glycol-based hydrogel delivered as two liquid precursors that polymerize within the target vessel in a unique animal model of severe solid organ injury with and without dilutional coagulopathy.

Anesthetized swine (n= 36, 45± 3kg) had laparotomy and splenic externalization. Half underwent 50% isovolemic hemodilution with 6% hetastarch and cooling to 33°C-35°C (coagulopathic group). All animals had controlled 20mL/kg hemorrhage and endovascular proximal splenic artery access with a 4F catheter via a right femoral sheath. Splenic transection and 5-minute free bleeding were followed by treatment (n= 5/group) with 5mL of gelfoam slurry, three 6-mm coils, up to 6mL of hydrogel, or no treatment (n= 3, control). Animals received 15mL/kg plasma. This agent represents a promising future treatment for the embolization of traumatic solid organ and other injuries.

Metformin is associated with a reduced incidence and growth of abdominal aortic aneurysms (AAAs). The aim of the present study was to investigate the inhibitory effects of metformin on AAA development and possible underlying mechanisms in experimentally induced AAAs in mice, along with the possible synergistic effects of metformin and imatinib.

Angiotensin II was used to induce AAAs in apolipoprotein E knockout (



) mice for 28days. The mice were treated with metformin (n= 11), metformin combined with imatinib (n= 7), or vehicle (n= 12), starting 3days before angiotensin II infusion. Ultrasound examination was used to analyze aneurysm formation. Cholesterol and blood pressure levels were measured at the start and end of the study. Gene array and quantitative polymerase chain reaction were used to analyze the changes in gene expression in the aorta. Wire myography was used to study vascular function.

Metformin (n= 11) suppressed the formation and progression of AAAs by 50% compared with the vehicle cmportant to study as outcomes in humans. Future clinical trials using metformin are warranted in patients without diabetes with abdominal aortic aneurysms.

Retrospective studies of the effects of metformin in patients with aneurysm have so far only been performed of those with type 2 diabetes. The present study shows that metformin has effects on nondiabetic mice and revealed the mechanistic effects mediated by the drug that could also be important to study as outcomes in humans. Future clinical trials using metformin are warranted in patients without diabetes with abdominal aortic aneurysms.

Novel therapeutic angiogenic concepts for critical limb ischemia are still needed for limb salvage. E-selectin, a cell-adhesion molecule, is vital for recruitment of the stem/progenitor cells necessary for neovascularization in ischemic tissues. We hypothesized that priming ischemic limb tissue with E-selectin/adeno-associated virus (AAV) gene therapy, in a murine hindlimb ischemia and gangrene model, would increase therapeutic angiogenesis and improve gangrene.

FVB/NJ mice were given intramuscular hindlimb injections of either E-selectin/AAV or LacZ/AAV and then underwent induction of gangrene via femoral artery ligation and concomitant systemic injections of the nitric oxide synthesis inhibitor L-NAME (L-N

-Nitro arginine methyl ester; 40mg/kg). Gangrene was evaluated via the Faber hindlimb appearance score. The rate of ischemic limb reperfusion and ischemic tissue angiogenesis were evaluated using laser Doppler perfusion imaging and DiI perfusion with confocal laser scanning microscopy of the ischemicngiogenesis, reperfusion, and limb functionality in mice with hindlimb ischemia and gangrene. Our findings highlight the reported novel gene therapy approach to critical limb ischemia as a potential therapeutic option for future clinical studies.

Quantitative methods for evaluating microstructure of arterial specimens typically rely on histologic techniques that involve random sampling, which cannot account for the unique spatial distribution of features in three dimensions.

To overcome this limitation, we demonstrate a nondestructive method for three-dimensional imaging of intact human blood vessels using microcomputed tomography (microCT). Human artery segments were dehydrated and stained in an iodine solution then imaged with a standard laboratory microCT scanner. Image visualization and segmentation was performed using commercially available and open source software.

Staining of cadaveric vessels with iodine enabled clear visualization of the arterial wall with microCT, preserved tissue morphology, and generated high-resolution images with a voxel size of 5.4μm. Various components of the arterial wall were segmented using a combination of manual and automatic thresholding algorithms.

Our approach allows for spatial mapping of human artery here is a valuable adjunct that can be used as a research tool to inform finite element modeling of arteries, quantify pathologic response (ie, neointimal hyperplasia and vascular calcification), and evaluate the tissue/device interface of implanted medical devices.

The objective of this study was to better understand the pathophysiology and underlying genetic mechanisms behind two abdominal aortic aneurysm (AAA) subtypes using computed tomographic imaging in combination with whole genome sequencing.

Patients with a known AAA and European ancestry were included in this investigation and underwent genetic and image analysis. Patients with AAAs and indications of descending thoracic aortic pathology (aortic dissection, penetrating aortic ulcers, intramural hematoma, atheromas, ulcerative plaque, and intramural ulceration, and intimal flaps/tears) were classified as having thoracic aortic disease, grouped together, and compared with patients with an AAA and a normal descending thoracic aorta. Whole genome sequencing was then performed on the 93 patients who had imaging features consistent with thoracic aortic disease and the 126 patients with a normal descending thoracic aorta.

The results of this study suggest one variant-level, four gene-level, and one gene set-leveaid surgeons in making future procedural and management decisions.

Abdominal aortic aneurysm (AAA) is a chronic inflammatory disease, which frequently results in fatal rupture; however, no pharmacologic treatment exists to inhibit AAA growth and prevent rupture. In this study, we investigated whether K-134, a novel phosphodiesterase 3 inhibitor, could limit the progression and rupture of AAA using multiple experimental models.

A hypoperfusion-induced AAA rat model was developed by inserting of a small catheter and via tight ligation of the infrarenal aorta. Rats were fed with a 0.15% K-134-containing diet (K-134(+) group) or a normal diet (K-134(-) group) from 7days before the experiment to 28days after model creation (pretreatment protocol). After the administration period, elastin fragmentation, macrophage infiltration, reactive oxygen species expression, matrix metalloproteinase levels, aneurysmal tissue hypoxia, and adventitial vasa vasorum (VV) stenosis were assessed. In the delayed treatment protocol, rats with AAA >3mm were randomly divided to K-134(+) or K-134ing new therapeutic option for AAAs and could undergo clinical trials for patients with small AAA.The development of venous intimal hyperplasia (VIH) has not been fully studied. At present, there are no drugs approved for VIH inhibition; to investigate such alternatives, we aimed to compare paclitaxel with cilostazol in VIH early inhibition in a preliminary experimental model of balloon angioplasty. Twenty-eight male New Zealand rabbits were randomly divided into two groups cilostazol (A) and paclitaxel (B), which underwent femoral vein barotrauma by a 4 mm balloon angioplasty. The VIH model was previously tested in controls obtaining an 80% increase of subintimal area (SIA) compared with veins without injury (from 0.12 mm2 [standard deviation (SD), 0.05] to 0.86 mm2 [SD, 0.08]). Group A received 20 mg/kg twice daily; group B angioplasty was performed with a single-dose paclitaxel-coated balloon. Seven days later rabbits were euthanized, and vein tissue samples were taken for histological analysis. The primary end point was SIA measure expressed in mm2, and the anticipated difference between treatments waprocedures, for example in May Thurner syndrome. Paclitaxel and cilostazol seem to have a promising role. Finally, the present study could inspire a research line to reduce stent placement and increase patency after venous angioplasty.

Although veins have a thinner middle layer compared with arteries, smooth muscle cells appear to play an important role in venous stenosis after angioplasty. The study of smooth muscle cell response after barotrauma may have clinical applications in the endovascular treatment of venous stenosis, because at the moment, there is no medication indicated to prolong patency after venous endovascular procedures, for example in May Thurner syndrome. Paclitaxel and cilostazol seem to have a promising role. Finally, the present study could inspire a research line to reduce stent placement and increase patency after venous angioplasty.

We have previously demonstrated that human abdominal aortic aneurysm (AAA) rupture occurs in zones of low wall shear stress where flow recirculation and intraluminal thrombus (ILT) deposition are increased. Matrix metalloproteinase-9 (MMP-9) is involved in the pathogenesis of AAA via its lytic effect on collagen and elastin. We hypothesize that flow-mediated ILT deposition promotes increased local inflammatory and MMP-9 activity that leads to AAA wall degeneration. The purpose of this study was to examine the correlation between predicted pulsatile flow dynamics and regional differences in MMP-9, elastin, collagen, and ILT deposition in human AAA.

Full-thickness aortic tissue samples were collected from 24 patients undergoing open AAA repair. Control infrarenal aortic tissue was obtained from 6 patients undergoing aortobifemoral bypass. Full-thickness aortic tissue and ILT were assessed for MMP-9 levels using a cytokine array assay. Histologic and immunohistochemical assessment of inflammation, collagen and elastin content, and MMP-9 levels were also measured.

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