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Investigative Radiology Sep 2017The aim of this study was to demonstrate a new clinically translatable ultrasound molecular imaging approach, modulated acoustic radiation force-based imaging, which is...
OBJECTIVES
The aim of this study was to demonstrate a new clinically translatable ultrasound molecular imaging approach, modulated acoustic radiation force-based imaging, which is capable of rapid and reliable detection of inflammation as validated in mouse abdominal aorta.
MATERIALS AND METHODS
Animal studies were approved by the Institutional Animal Care and Use Committee at the University of Virginia. C57BL/6 mice stimulated with tumor necrosis factor α, or fed with a high-fat diet, were used as inflammation (MInflammation) and diet-induced obesity (DIO) (MDIO) models, respectively. C57BL/6 mice, not exposed to tumor necrosis factor α or DIO, were used as controls (MNormal). P-selectin-targeted (MBP-selectin), vascular cell adhesion molecule (VCAM)-1-targeted (MBVCAM-1), and isotype control (MBControl) microbubbles were synthesized by conjugating anti-P-selectin, anti-VCAM-1, and isotype control antibodies to microbubbles, respectively. The abdominal aortas were imaged for 180 seconds during a constant infusion of microbubbles. A parameter, residual-to-saturation ratio (RSR), was used to assess P-selectin and VCAM-1. Statistical analysis was performed with the Student t test.
RESULTS
For the inflammation model, RSR of the MInflammation + MBP-selectin group was significantly higher (40.9%, P < 0.0005) than other groups. For the DIO model, RSR of the MDIO + MBVCAM-1 group was significantly higher (60.0%, P < 0.0005) than other groups. Immunohistochemistry staining of the abdominal aorta confirmed the expression of P-selectin and VCAM-1.
CONCLUSIONS
A statistically significant assessment of P-selectin and VCAM-1 in mouse abdominal aorta was achieved. This technique yields progress toward rapid targeted molecular imaging in large blood vessels and thus has the potential for early diagnosis, treatment selection, and risk stratification of atherosclerosis.
Topics: Animals; Aorta, Abdominal; Disease Models, Animal; Inflammation; Mice; Mice, Inbred C57BL; Microbubbles; Molecular Imaging; Reproducibility of Results; Ultrasonography
PubMed: 28430714
DOI: 10.1097/RLI.0000000000000373 -
The Journal of Thoracic and... Jul 2018We sought to identify the risk factors for abdominal aortic remodeling after thoracic endovascular aortic repair in patients with chronic DeBakey IIIb aneurysm.
OBJECTIVES
We sought to identify the risk factors for abdominal aortic remodeling after thoracic endovascular aortic repair in patients with chronic DeBakey IIIb aneurysm.
METHODS
From 2012 to 2016, 70 patients underwent thoracic endovascular aortic repair for chronic DeBakey IIIb aneurysm. The abdominal aortic diameter was measured at 3 different levels (celiac trunk, renal artery, and infrarenal aorta). Abdominal aorta status was classified as expansion or stable. Expansion status was assigned when the abdominal aortic diameter was increased over 5 mm at least 1 level. Otherwise, it was classified as stable status. Forty-six of 70 patients underwent more than 2 postoperative imaging studies. In those patients (n = 46), abdominal aortic volume was measured from celiac trunk to inferior mesenteric artery. A linear mixed-effect model was used to analyze the overall fate of abdominal aortic volume.
RESULTS
No in-hospital mortality occurred. The mean follow-up and imaging follow-up duration were 26 and 17 months, respectively. Sixty-one patients (87.1%) demonstrated thoracic false-lumen thrombosis. Although false-lumen thrombosis was achieved, 15 patients (24.6%) demonstrated the expansion status. In volumetric analysis, the total abdominal aortic volume was increasing over time (0.603 cm/mo; P < .001) and the residual intima tears were identified as an independent anatomic risk factor for an enlarged abdominal aorta.
CONCLUSIONS
An enlarged abdominal aorta in chronic DeBakey IIIb aneurysm can be frequently recognized even after successful endovascular treatment. The residual intima tears were the only identified risk factor for change in a dissected abdominal aneurysm. We suggest careful abdominal aorta evaluation and additional procedures on the false lumen if necessary.
Topics: Adult; Aged; Aorta, Abdominal; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Aortography; Blood Vessel Prosthesis Implantation; Chronic Disease; Computed Tomography Angiography; Endovascular Procedures; Female; Humans; Male; Middle Aged; Retrospective Studies; Risk Factors; Time Factors; Treatment Outcome; Vascular Remodeling
PubMed: 29709360
DOI: 10.1016/j.jtcvs.2018.03.118 -
World Journal of Gastroenterology Feb 2004To study the morphologic and cellular immunologic changes after homologous transplantation of the abdominal aorta in rats after programmed cryopreservation (-196...
AIM
To study the morphologic and cellular immunologic changes after homologous transplantation of the abdominal aorta in rats after programmed cryopreservation (-196 degrees).
METHODS
Abdominal aorta was harvested from anesthetized Spraque Dawley (SD) rats for cryopreservation (group B) or immediate implantation (group A). The survival rates and apoptotic rates of aortic endothelial cells (ECs) were examined. The patency rates, histology and cellular immunologic changes of the abdominal aorta were examined on days 1, 3, 7, 14, 30, 60 after transplantation respectively.
RESULTS
The survival rate of ECs after programmed cryopreservation was 90.1+/-1.79%, about 3.4% lower than that of uncryopreservation (93.5+/-1.96%). The apoptotic rates of ECs was increased after cryopreservation (7.15% vs 4.86%, P<0.05). The patency rate of group B was significantly higher than that of group A (91.6+/-12.9% vs 62.5+/-26.2%, P<0.01). CD4/CD8 ratio, TCR alpha beta and CD11b/CD18 ratio of group B were significantly lower than those of group A (P<0.05). Revivification of the cryopreserved abdominal aorta showed normal adventitia and intact smooth muscle cells.
CONCLUSION
Cryopreservation can reduce homologous abdominal aortic antigenecity. Even if without administration of immunosuppressive agents, it is still feasible to implement homologous artery grafting in rats.
Topics: Animals; Aorta, Abdominal; Apoptosis; CD11b Antigen; CD18 Antigens; Cell Survival; Cryopreservation; Endothelium, Vascular; Female; Male; Rats; Rats, Sprague-Dawley; Receptors, Antigen, T-Cell, alpha-beta; T-Lymphocytes; Transplantation, Homologous; Vascular Patency
PubMed: 14966916
DOI: 10.3748/wjg.v10.i4.555 -
Experimental Animals Feb 2023Previous abdominal aortic aneurysm (AAA) animal modeling methodologies were either expensive or complicated. Here, we developed a novel AAA model which was simple to set...
Previous abdominal aortic aneurysm (AAA) animal modeling methodologies were either expensive or complicated. Here, we developed a novel AAA model which was simple to set up and generated minimal calcification. Twenty-four rats were divided randomly into four groups. Groups 1, 2 and 3 underwent surgery in which 15% hydrochloric acid (HCl) was applied periarterially to the abdominal aorta for 5 min, followed by sacrifice 1 week (group 1), 2 weeks (group 2), and 4 weeks (group 3) after surgery. The maximum aortic diameter (MAD) was measured at surgery and before animal sacrifice. Rats in group 4 were sham-treated. The MADs in group 1, 2 and 3 showed significant dilation compared with group 4, with a mean dilation rate of 33.8% in the first week after surgery. Histopathological examination revealed infiltration of macrophages into the adventitia, obvious apoptosis of smooth muscle cells, and rupture and collapse of the elastic fibers. Furthermore, no calcification was observed in the dilated aorta. The mRNA expression levels of inflammatory factors were at least two-fold higher in group 1 than in group 4, indicating significant inflammatory response in the progression of AAA information. In conclusion, periarterial application of 15% HCl is a convenient and reliable model to create an abdominal aortic aneurysm in rats, and the potential development mechanism may be related to the proinflammatory effects of HCl.
Topics: Rats; Animals; Hydrochloric Acid; Aortic Aneurysm, Abdominal; Aorta, Abdominal; Disease Models, Animal; Macrophages
PubMed: 36058844
DOI: 10.1538/expanim.22-0020 -
Cardiovascular Drugs and Therapy Oct 2018Perivascular adipose tissue (PVAT) surrounds the arterial adventitia and plays an important role in vascular homeostasis. PVAT expands in obesity, and inflamed PVAT can...
PURPOSE
Perivascular adipose tissue (PVAT) surrounds the arterial adventitia and plays an important role in vascular homeostasis. PVAT expands in obesity, and inflamed PVAT can locally promote endothelial dysfunction and atherosclerosis. Here, using adipose tissue transplantation, we tested the hypothesis that expansion of PVAT can also remotely exacerbate vascular disease.
METHODS
Fifty milligrams of abdominal aortic PVAT was isolated from high-fat diet (HFD)-fed wild-type mice and transplanted onto the abdominal aorta of lean LDL receptor knockout mice. Subcutaneous and visceral adipose tissues were used as controls. After HFD feeding for 10 weeks, body weight, glucose/insulin sensitivity, and lipid levels were measured. Adipocytokine gene expression was assessed in the transplanted adipose tissues, and the thoracic aorta was harvested to quantify atherosclerotic lesions by Oil-Red O staining and to assess vasorelaxation by wire myography.
RESULTS
PVAT transplantation did not influence body weight, fat composition, lipid levels, or glucose/insulin sensitivity. However, as compared with controls, transplantation of PVAT onto the abdominal aorta increased thoracic aortic atherosclerosis. Furthermore, PVAT transplantation onto the abdominal aorta inhibited endothelium-dependent relaxation in the thoracic aorta. MCP-1 and TNF-α expression was elevated, while adiponectin expression was reduced, in the transplanted PVAT tissue, suggesting augmented inflammation as a potential mechanism for the remote vascular effects of transplanted PVAT.
CONCLUSIONS
These data suggest that PVAT expansion and inflammation in obesity can remotely induce endothelial dysfunction and augment atherosclerosis. Identifying the underlying mechanisms may lead to novel approaches for risk assessment and treatment of obesity-related vascular disease.
Topics: Adiponectin; Adipose Tissue, White; Adiposity; Animals; Aorta, Abdominal; Aorta, Thoracic; Atherosclerosis; Chemokine CCL2; Diet, High-Fat; Disease Models, Animal; Disease Progression; Inflammation Mediators; Mice, Inbred C57BL; Mice, Knockout; Paracrine Communication; Plaque, Atherosclerotic; Receptors, LDL; Signal Transduction; Tumor Necrosis Factor-alpha; Vasodilation
PubMed: 30097828
DOI: 10.1007/s10557-018-6821-y -
Annals of Biomedical Engineering Jul 2013The current clinical management of abdominal aortic aneurysm (AAA) disease is based to a great extent on measuring the aneurysm maximum diameter to decide when timely... (Review)
Review
The current clinical management of abdominal aortic aneurysm (AAA) disease is based to a great extent on measuring the aneurysm maximum diameter to decide when timely intervention is required. Decades of clinical evidence show that aneurysm diameter is positively associated with the risk of rupture, but other parameters may also play a role in causing or predisposing the AAA to rupture. Geometric factors such as vessel tortuosity, intraluminal thrombus volume, and wall surface area are implicated in the differentiation of ruptured and unruptured AAAs. Biomechanical factors identified by means of computational modeling techniques, such as peak wall stress, have been positively correlated with rupture risk with a higher accuracy and sensitivity than maximum diameter alone. The objective of this review is to examine these factors, which are found to influence AAA disease progression, clinical management and rupture potential, as well as to highlight on-going research by our group in aneurysm modeling and rupture risk assessment.
Topics: Aorta, Abdominal; Aortic Aneurysm, Abdominal; Biomechanical Phenomena; Humans; Models, Cardiovascular; Risk Assessment
PubMed: 23508633
DOI: 10.1007/s10439-013-0786-6 -
BMC Women's Health Dec 2022Endometrial carcinoma (EC) is a common malignant tumor of the female reproductive system, often accompanied by lymph node metastasis. Artificial vascular implantation is...
Resection of inferior vena cava, abdominal aorta, bilateral common iliac arteries, and bilateral partial external iliac arteries with artificial vessel replacement during radical endometrial cancer surgery: a case report.
BACKGROUND
Endometrial carcinoma (EC) is a common malignant tumor of the female reproductive system, often accompanied by lymph node metastasis. Artificial vascular implantation is a common surgical treatment for mediastinal tumors and abdominal aortic aneurysms but is rarely used in gynecological surgery.
CASE PRESENTATION
A 54-year-old female patient was first admitted to the hospital in January 2018 due to "irregular vaginal bleeding over 3 months". CT showed a mass in the uterine cavity, and several swollen lymph nodes in the retroperitoneum and pelvic cavity. The initial diagnosis was an endometrial malignant tumor. We performed radical endometrial cancer surgery with parallel resection of inferior vena cava, abdominal aorta, bilateral common iliac arteries, bilateral external iliac arteries, and artificial vessel replacement, which was successful, with good postoperative recovery and no lesion progression at 3 years postoperative follow-up.
CONCLUSION
This is an early case of gynecological clinical use of prostheses. Through multidisciplinary cooperation, the surgical resection rate of patients with EC in radical surgery was improved without serious fatal complications and achieved a high long-term postoperative survival rate.
Topics: Humans; Female; Middle Aged; Aorta, Abdominal; Iliac Artery; Vena Cava, Inferior; Lymph Node Excision; Endometrial Neoplasms
PubMed: 36578004
DOI: 10.1186/s12905-022-02120-2 -
Journal of Biological Physics Mar 2015Different material models for an idealized three-layered abdominal aorta are compared using computational techniques to study aneurysm initiation and fully developed...
Investigation of material modeling in fluid-structure interaction analysis of an idealized three-layered abdominal aorta: aneurysm initiation and fully developed aneurysms.
Different material models for an idealized three-layered abdominal aorta are compared using computational techniques to study aneurysm initiation and fully developed aneurysms. The computational model includes fluid-structure interaction (FSI) between the blood vessel and the blood. In order to model aneurysm initiation, the medial region was degenerated to mimic the medial loss occurring in the inception of an aneurysm. Various cases are considered in order to understand their effects on the initiation of an abdominal aortic aneurysm. The layers of the blood vessel were modeled using either linear elastic materials or Mooney-Rivlin (otherwise known as hyperelastic) type materials. The degenerated medial region was also modeled in either linear elastic or hyperelastic-type materials and assumed to be in the shape of an arc with a thin width or a circular ring with different widths. The blood viscosity effect was also considered in the initiation mechanism. In addition, dynamic analysis of the blood vessel was performed without interaction with the blood flow by applying time-dependent pressure inside the lumen in a three-layered abdominal aorta. The stresses, strains, and displacements were compared for a healthy aorta, an initiated aneurysm and a fully developed aneurysm. The study shows that the material modeling of the vessel has a sizable effect on aneurysm initiation and fully developed aneurysms. Different material modeling of degeneration regions also affects the stress-strain response of aneurysm initiation. Additionally, the structural analysis without considering FSI (called noFSI) overestimates the peak von Mises stress by 52% at the interfaces of the layers.
Topics: Aorta, Abdominal; Aortic Aneurysm, Abdominal; Blood Viscosity; Disease Progression; Elasticity; Humans; Linear Models; Models, Cardiovascular; Stress, Mechanical
PubMed: 25624113
DOI: 10.1007/s10867-014-9372-x -
Journal of Vascular Surgery Feb 2014
Topics: Aorta, Abdominal; Aorta, Thoracic; Cardiovascular Agents; Female; Humans; Male; Vascular System Injuries; Wounds, Nonpenetrating
PubMed: 24342061
DOI: 10.1016/j.jvs.2013.09.056 -
Biomedical Engineering Online Nov 2003The goal of this work was to determine wall shear stress (WSS) patterns in the human abdominal aorta and to compare these patterns to measurements of intimal thickness... (Comparative Study)
Comparative Study
PURPOSE
The goal of this work was to determine wall shear stress (WSS) patterns in the human abdominal aorta and to compare these patterns to measurements of intimal thickness (IT) from autopsy samples.
METHODS
The WSS was experimentally measured using the laser photochromic dye tracer technique in an anatomically faithful in vitro model based on CT scans of the abdominal aorta in a healthy 35-year-old subject. IT was quantified as a function of circumferential and axial position using light microscopy in ten human autopsy specimens.
RESULTS
The histomorphometric analysis suggests that IT increases with age and that the distribution of intimal thickening changes with age. The lowest WSS in the flow model was found on the posterior wall inferior to the inferior mesenteric artery, and coincided with the region of most prominent IT in the autopsy samples. Local geometrical features in the flow model, such as the expansion at the inferior mesenteric artery (common in younger individuals), strongly influenced WSS patterns. The WSS was found to correlate negatively with IT (r2 = 0.3099; P = 0.0047).
CONCLUSION
Low WSS in the abdominal aorta is co-localized with IT and may be related to atherogenesis. Also, rates of IT in the abdominal aorta are possibly influenced by age-related geometrical changes.
Topics: Adult; Aging; Aorta, Abdominal; Autopsy; Computer Simulation; Female; Hemodynamics; Humans; Male; Middle Aged; Models, Cardiovascular; Radiography; Reference Values; Stress, Mechanical; Tunica Intima
PubMed: 14641919
DOI: 10.1186/1475-925X-2-18