Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Clinical experience with 5 patients who had complications of atherosclerosis within the aorta at the site of the obliterated ductus arteriosus suggested the occurrence of clinically significant preferential atherosclerosis at this location. To examine this hypothesis, the clinical findings in these patients (4 with saccular aneurysm and 1 with systemic emboli from an ulcerated plaque at this location) were correlated with postmortem examination of the aortic isthmus in 40 consecutive cadavers. The point of ductal closure was the area of most severe atheromatous involvement in 32 of the 40 cadavers, and 25 of the 40 specimens demonstrated ulcerated plaques at this location. Microscopical examination consistently demonstrated intimal irregularity or disruption and thinning of the aortic media in this area. These studies indicate that preferential atherosclerosis occurs at the aortic end of the obliterated ducts arteriosus and that these atherosclerotic changes can be a clinically significant development.
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PMID:Preferential atherosclerosis at the aortic junction of the ligamentum arteriosum: clinical significance and pathological correlation. 93 39

Ageing and degenerative changes of the human aorta are associated with medial thinning and a reduced dry weight content of elastin. The metabolic stability of cross-linked elastin was investigated by measuring the accumulation of D-aspartate with ageing in insoluble elastin isolated from human aorta. D-Aspartate accumulation in elastin was compared with D-aspartate accumulation in aortic collagen and an elastin bound glycoprotein fraction. The D-aspartate content of elastin, purified from infrarenal aorta; increased linearly with age from 3% of the total aspartate in youth to 13% in the mid 80s. In contrast the D-aspartate content of aortic collagen remained invariant (3-5% of the total aspartate) from youth to old age. The apparent first order rate constant for the racemization of L-aspartate in elastin was 1.14 x 10(-3). The D-aspartate content of the elastin bound glycoproteins increased by only a small amount, from 3% in the mid 30s to 6% in the mid 80s. These results argue for the metabolic stability of aortic elastin as compared with the fibrillar collagens of the human aorta. Both the rate of racemization and the specific accumulation of D-aspartate in elastin, but not collagen, indicates that mature cross-linked elastin is not synthesized in the adult aorta.
Atherosclerosis 1992 Dec
PMID:On the accumulation of D-aspartate in elastin and other proteins of the ageing aorta. 146 64

1. Atherosclerosis and aneurysm of the abdominal aorta are associated with thinning of the medial connective tissue. We have investigated the presence of the connective-tissue-degrading metalloproteinases in homogenates prepared from atherosclerotic, aneurysmal and control aortic media. 2. Gelatinase activity was much increased in homogenates from atherosclerotic and aneurysmal aorta [10.9 +/- 1.8 and 13.3 +/- 3.3 micrograms of gelatin hydrolysed h-1 (mg of protein)-1 respectively]. This gelatinase activity was highest at the luminal aspect of the aortic media, where the activity increased three- to five-fold after the destruction of alpha 2-macroglobulin. Zymograms demonstrated the principal gelatinase in atherosclerotic aorta to have a molecular mass of about 92 kDa, whereas in aneurysmal aorta there was a spectrum of gelatinase activity from 92 to 55 kDa. 3. Collagenase and stromelysin (proteoglycanase) could be detected by immunoblotting in homogenates of aneurysmal aorta, but rarely in atherosclerotic aorta and never in control aorta. Collagenase and stromelysin activities were low, but increased two- to three-fold after the destruction of tissue inhibitor of metalloproteinases. Collagenase and stromelysin activities were highest at the adventitial aspect of aneurysmal media. 4. The secretion of gelatinase by inflammatory cells at the intima of diseased aorta could have a pathological role in establishing atherosclerotic plaques and medial thinning. Secretion of collagenase, gelatinase and stromelysin from the adventitia could accelerate connective tissue degradation in the media of aneurysmal aorta.
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PMID:Metalloproteinases in degenerative aortic disease. 165 68

Hypertension is a known risk factor for atherosclerosis. We hypothesize that hypertension causes artery wall hypoxia that contributes to the formation of atherosclerotic lesions. Therefore, we examined the effect of hypertension on the transarterial wall oxygen gradient of the rabbit aorta. Hypertensive rabbits were created by unilateral nephrectomy and contralateral renal artery narrowing. Transarterial wall oxygen gradients of the infrarenal aorta were measured using an oxygen microelectrode 14-16 weeks (short-term hypertension) and 56-58 weeks (long-term hypertension) after the rabbits were made hypertensive. The transarterial wall oxygen gradients showed significant differences among the groups. Short-term hypertension caused significantly higher oxygen tensions in the outer 30% of the artery wall and significant thinning of the artery wall when compared with long-term hypertension and control groups. Long-term hypertension caused significantly lower oxygen tensions in the inner 40% of the artery wall and significant thickening of the artery wall when compared with short-term hypertension and control groups. These changes were noted despite no difference in the partial pressure of oxygen in arterial blood or visual evidence of atherosclerotic lesion formation in the three groups. These findings suggest that hypertension alters the transarterial wall oxygen gradient. This altered transarterial wall oxygen gradient may contribute to the formation of atherosclerotic lesions.
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PMID:Changes in the aortic wall oxygen tensions of hypertensive rabbits. Hypertension and aortic wall oxygen. 173 Apr 36

During repair of 12 atherosclerotic abdominal aortic aneurysms, fresh samples of aneurysm wall were obtained. Histology confirmed the presence of advanced atherosclerosis associated with medial thinning and a variable aortic adventitial chronic inflammatory cell infiltrate. Monoclonal antibodies were used to identify the inflammatory cells throughout the aortic wall. The majority of lymphocytes in the aortic adventitia were B-cells. B-cells were not present in atheromatous plaques. T-cells, predominantly T-helper cells, were found in atheromatous plaques and in aortic adventitia. The majority of lymphocytes and macrophages in aortic adventitia and most vascular endothelial cells were HLA-DR positive. Ki-67 staining was found in B-cells and T-helper cells, indicating that these cells were proliferating. Occasional lymphocytes were BerH2 positive, indicating that some lymphocytes were activated. These findings suggest that chronic periaortitis is an active, immunologically mediated, local complication of advanced human atherosclerosis.
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PMID:Immunohistochemical characterization of inflammatory cells associated with advanced atherosclerosis. 207 87

A review of the histology of 440 sections of atherosclerotic aortas and arteries showed that 85% contained advanced atherosclerotic plaques. Of these, 92% showed some degree of adventitial inflammation with subclinical chronic periaortitis in 49%. A review of 20 cases of clinical chronic periaortitis, which included 12 cases of inflammatory aneurysm and 8 cases of idiopathic retroperitoneal fibrosis, showed that there were no significant differences between them apart from an increase in aortic diameter in the former. The term chronic periaortitis is appropriate for the spectrum of subclinical and clinical forms of chronic adventitial inflammation associated with advanced atherosclerosis and medial thinning.
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PMID:The spectrum of chronic periaortitis. 219 63

To determine whether aneurysms form in experimental diet-induced atherosclerosis, we reviewed our experience with cynomolgus monkeys (n = 268) and rhesus monkeys (n = 175) fed an atherogenic diet for various lengths of time. Many animals in long-term experiments were fed "regression" diets and cholestyramine to lower cholesterol levels after lesions were established. No aneurysms were found in animals on normal diet. There were no aneurysms in 252 animals fed an atherogenic diet with or without regression for 12 months or less. However, aneurysms formed in 13% of cynomolgus monkeys (4 of 31) and 1% (1 of 107) rhesus monkeys on an atherogenic regimen for 16 to 24 months. Four of the five animals with aneurysms were on a regression diet and cholestyramine for 4 to 12 months. The fifth was fed the atherogenic diet for 20 months without subsequent regression. Aneurysms were prominent and involved the thoracic and abdominal aorta, innominate artery, carotid arteries, iliac and femoral arteries, and formed in areas most involved with plaque formation in both species. Histologic evidence was found of thinning of the media and atrophy with loss of normal architecture. The higher incidence of aneurysms in cynomolgus monkeys was associated with greater media destruction than was noted in the rhesus. These data support the thesis that aneurysm formation is a manifestation of atherosclerosis. In primate atherosclerosis, aneurysms form only after prolonged exposure to the atherogenic regimen, even in the presence of declining serum cholesterol levels. Matrix fibers in plaques may provide structural support to the aortic wall where there is underlying atrophy of the media. With time or declining serum cholesterol levels or both, plaques may atrophy leaving an aortic wall too thin to support increasing mural tension, leading to aneurysmal enlargement.
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PMID:Aneurysm formation in experimental atherosclerosis: relationship to plaque evolution. 239 95

The thickness of the sclera has been morphologically examined in 165 cadaver eyes and the thickness of the reticular plate (RP) in 68 eyes in open-angle glaucoma, atherosclerosis, and involution. The measurements have shown that the sclera and RP are thinner in atherosclerosis than in the control, this process being more manifest in the RP. The RP supporting characteristics deteriorate even in vascular abnormalities. Open-angle glaucoma is associated with a most significant thinning of the sclera (t up to 5.33), but when this process develops far, the thinning ceases (t = 0.06). RP thinning is more marked (t = 2.2 = 7.58) and does not cease in case of a far-developed process. The values of the pressure on the posterior segment of the eye in health and in glaucoma are presented; this pressure is drastically elevated in glaucoma, which fact may explain the stretching of the entire posterior segment (of the sclera by 1.5 times and of the RP by 8.5 times). Since the mechanical properties of the RP are poor and the plate virtually disappears, the optic nerve is devoid of its support.
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PMID:[Quantitative biochemical shifts in the connective tissue of the rear section of the eyeball in glaucoma and atherosclerosis]. 272 63

An immunohistochemical study was undertaken in an attempt to localise immunoglobulin in sections of human advanced atherosclerosis with thinning of the media (sub-clinical periaortitis) and without thinning of the media as well as sections of artery from patients with clinical periaortitis. The findings were that in routinely processed sections of advanced atherosclerosis showing medial attenuation and in sections from cases of clinical periaortitis IgG, and to a lesser extent IgM, was localised to insoluble lipid, ceroid, within the atheroma itself. It is suggested that these observations support the hypothesis that chronic periaortitis has an auto-allergic cause and that the allergen may be a component of ceroid, which is elaborated within the atheroma.
Atherosclerosis 1986 Aug
PMID:The localisation of immunoglobulin in chronic periaortitis. 353 Feb 62

The usefulness of coronal and sagittal sections of the cardiovascular system by magnetic resonance imaging was evaluated. Coronal, sagittal and transverse spin echo scans using ECG-non-gating and gating during systole and diastole were performed for five normal volunteers, 91 with heart diseases (25 valvular disease, 28 ischemic heart disease, 14 cardiomyopathies, 14 congenital malformations, four pericardial diseases, and six others) and 32 patients with aortic abnormalities (17 aneurysms, 10 dissections and five others) using a 2.5 KGauss unit. Cardiac gating necessitated six to eight min per scan, but it was mandatory to obtain clear images of the details. On the other hand, in most of the aortic abnormalities, diagnostic images were obtained by the ECG-non-gating technique which required only about 2.5 min per scan. Coronal and sagittal sections were useful for estimating the entire shape and size of each cardiac chamber and intracardiac thrombi, the extent of postinfarctional wall thinning and cardiac aneurysms, and hypertrophy or narrowing of both the ventricular outflow tracts and apex. These planes were particularly useful, and more contributory than transverse planes for detecting inferior myocardial damage such as infarction. A few coronal and sagittal scans were sufficient to diagnose extensive lesions of the aorta, such as atherosclerosis, dissections and the aortitis syndrome. Local lesions such as coarctation, supravalvular aortic stenosis, annulo-aortic ectasia and aneurysm, especially those originating in the inferior wall of the aortic arch were easily discovered. Since the main arteries, such as the innominate, left common carotid, left subclavian and renal arteries, were clearly demonstrated by coronal images, coronal scans were considered more useful than transverse ones for observing the relationship between these arteries and dissections or aneurysms of the arch and of the abdominal aorta.
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PMID:[Magnetic resonance imaging of cardiovascular diseases: advantages of coronal and sagittal planes]. 384 98


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