Aorta spectrum

In arteriosclerotic processes, the mucopolysaccharide spectrum changes Buddecke (B17) has demonstrated that the amounts of sulfated mucopolysaccharides are increased by 50, whereas the amounts of hyaluronic acid and chondroitin fall to 40% and 15% of their original values, respectively. The increase of sulfated mucopolysaccharides in arteriosclerotic aortae is related to the increased deposition of calcium. 

Focal disease follows a bacteremic phase and involves a wide spectrum of organs. These include liver, gallbladder, aorta (aortic aneurysms), heart valves with stenosis or insufficiency, joints (septic arthritis), bones, urinary tract and soft tissue. The most common serotypes of Salmonella causing focal infection are S. choleraesuis and S. typhimurium. 

Input impedance measurements have identified a variation in the frequency spectrum. While experimental studies have not provided an explanation for the origin of these variations, the current model ties them to autoregulation delay (tq). The model predicts that the spectrum should follow an oscillatory pattern, particularly for frequencies at and below the heart rate. Moreover, the sinusoidal steady state may not be easily achieved experimentally. The model required over one minute duration to obtain the steady state response. The model further predicts an erratic or random variation in the impedance spectrum if the steady state was not obtained. Another explanation could be that the different vascular beds may possess shghtly different delay times. When measured at the aorta, this may appear as impedance scatter. Other researchers have attributed the source of impedance variations to nonlinear vascular properties [Stergiopulos et al., 1995b]. 

Fig. 3.25. Single reflection spectrum of adult human aorta containing atherosclerotic plaque. The bands near 2320 and 2350 cm" were caused by COj. (Parker and Ans, 1967.)...

Stress relaxation relations for human arteries are not available however, Tanaka and Fung [48] studied the stress relaxation spectrum of the canine aorta. They expressed the stress history with respect to a step change in strain in the form ... 

Figure 18 Comparison of Raman spectra collected of sheep aorta in vivo and in vitro (a) spectrum of aorta collected in vivo arrows indicate most prominent signal contributions of blood (b) in vitro spectrum of aorta (luminal side) (c) in vitro spectrum of freshly drawn heparinized blood. Experimental conditions laser power =100 mW laser wavelength = 830 nm signal collection time = 30 sec Visionex Enviva fiber-optic probe coupled to a customized Renishaw system 100 Raman spectrometer.

The extent of aortic involvement represented a spectrum for the normal and for the diabetic aged monkeys. The normal monkeys ranged from moderate to about 50% sudanophilic blush and some contained roughened streaks and a few small discrete lesions. Of the three aged diabetic monkeys, the one with the least involvement had greater than 75% sudanophilia and numerous lesions at the intercostal and renal arteries and in the arch. The other two had extensive lesion involvement of the aorta which covered 65 to 85% of the surface. The aortas of the juvenile diabetics were clear and free of any atherosclerotic involvement. The most logical... 

Fig. 1. The above pathways for fatty acid synthesis have been demonstrated to be present in the aorta. The thickness of the arrows denotes the author s interpretation of the relative contribution to total synthesis made by the three intracellular sites. The mitochondrial pathway has the largest capacity to utilize acetate for the elongation of available acyl units. The latter are derived from plasma free fatty acid (FFA) and lipolysis of tissue triglyceride (TG). The cytosol has a limited capacity to synthesize fatty acids from acetate because of minimal acetyl-CoA carboxylase (ACC) activity. The significance of fatty acid synthetase (FAS) activity is dubious in the absence of a source of malonyl-CoA. A microsomal elongation-desaturation pathway can synthesize a spectrum of saturated (SAT) and unsaturated (UNSAT) long-chain fatty acids, similar to the products of the mitochondrial system.

I must emphasize the importance of studies of coronary atherosclerosis rather than just aortic atherosclerosis. First, the coronary arteries are anatomically different from the aorta, and consequently have a different overall metabolic behavior. Secondly, arteries from the several parts of the cardiovascular system are subject to a spectrum of dynamic forces from inside and outside the vessel walls which produce different modes of nutrition in the walls of the various kinds of arteries. Metabolic nutrition. Including provision of oxygen to the coronary muscle itself, depends on the integrity of not only the large coronary arteries but to a large extent on the small vessels within the muscle. Whenever the delivery of blood with its oxygen and nutrients is decreased in the heart, further problems develop within the heart muscle, eventually producing diminished performance and finally failures. 

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