Intima structures

Heterozygous carriers of functionally relevant mutations usually present with HDL cholesterol levels that are frequently below the fifth percentile. As would be expected, apoA-I levels are also frequently below the fifth percentile (i.e., < 1.05 g/1 and < 1.1 g/1 in Caucasian men and women, respectively). In most cases, heterozygous carriers of apoA-I variants do not present with specific clinical symptoms. An important exception are some structural apoA-I variants with amino acid substitutions in the amino terminus, which have been detected in patients with familial amyloidosis of the liver, the intestine, the kidney, the heart, peripheral nerves, and in the skin. In addition, some apoA-I variants like apoA-I L178P or L159P have been associated with increased risk of premature coronary heart disease or enhanced progression of carotid intima media thickness, whereas others did not show this association, or were even claimed to have reduced cardiovascular risk and advocated as possible agents for the treatment or prevention of atherosclerosis (notably apoA-I R173CMiiano) [22,43,53]. 

Fibrosis resulting in the loss of normal organ structures is the hallmark of chronic rejection. The fibrosis may be due to wound healing, which is then followed by the cellular necrosis of acute rejection. However, it must be pointed out that chronic rejection develops many times in the absence of acute rejection. Fibrosis may be a result of several diverse factors such as equation of chronic rejection with chronic delayed-type hypersensitivity reaction, injury to blood vessels and resulting response to chronic ischemia, the proliferation of smooth muscle cells in the intima of arterial walls producing vascular occlusion, or persistent viral infections that will induce cellular immune response. 

Furthmayr, H., Wiedemann, H., Timpl, R., Odermatt, E., and Engel,J (1983). Electron microscopical approach to a structural model of intima collagen. Biochem. J. 211, 303-311. 

Blood vessels include capillaries, arterioles, arteries, and veins. Each of these structures is composed of three layers the intima, media, and adventitia (Figure 3.12). For example, in elastic arteries the wall consists of an intimal layer containing endothelial cells and connective tissue a media containing smooth muscle cells, collagen, and elastic fibers and an adventitia containing collagen fibers, nerves, and blood vessels. In cross-section,... 

Figure 3.12. Structure of vessels. All vessels contain three layers the intima, media, and adventitia. In large elastic arteries, the intima is found beneath the internal elastic membrane and interfaces with the lumen. The media is found between the internal and external elastic membranes, and the adventitia is found outside the external elastic membrane. The media is less prominent in the other types of vessles.

The arterial wall of animals contains three layers the intima, media, and adventitia however, the wall structure of different vessels varies somewhat. The intima extends from the blood vessel lumen to the internal elastic... 

Diseases of elastic tissue are few compared with those that affect collagen, and in these destruction of preformed elastic fibers appears to occur only in localized areas, particularly in the walls of blood vessels and in the skin. In arteriosclerosis loss of elasticity and breakdown in the structure of the elastic elements in the media of arteries is accompanied by calcification of the media and the development of calcified plaques in the intima. Since calcification of the media may be seen to occur without the development of atheromata, it is thought that this change may be associated in the first place with age. Other age-related changes looked for have been changes in the gross content of elastin in the media and changes in the amino acid... 

The site of deposition of calcium in the aging human aorta has been studied more closely by Weissman and Weissman (1960). The gross calcification in the atherosclerotic plaques of the intima of the aging aorta is immediately obvious (Duff and McMillan, 19. )1) and appears to have little connection with the elastic structures. On the other hand, apparently independently of the development of plaques, progressive deposition of calcium takes place in the media with advancing age. It is important to know if this calcification of the media, which evidently leads to loss of elasticity, is directly associated with elastin rather than collagen or. some other components of the elastic tissue. 

A blood vessel can be divided anatomically into three distinct cylindrical sections when viewed under the optical microscope. Starting at the inside of the vessel, they are the intima, the media, and the adventitia. These structures have distinct functions in terms of the blood vessel physiology and mechanical properties. 

Vascular tissues comprise arteries, capillaries, and veins. Due to the risk and impact of vascular diseases in arteries, efforts have been focused on replacement and regeneration strategies. Arteries present a complex structure as they are composed of three layers, intima, media, and adventitia, each with a different composition and function. Additionally, artery composition changes depending on its location. 

The plaque deposits are just a few micrometers thick at these locations. The fibrillar structures, distribution of lipids, and smoothness of the surface were different for intima of control arteries as studied in CARS images at 2930 cm [83]. 

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