Arteries blockage

A number of rare genetic diseases involve collagen abnormalities, including Marfan s syndrome and the Ehlers-Danlos syndromes, which result in hyperextensible joints and skin. The formation of atheroselerotie plaques, which cause arterial blockages in advanced stages, is due in part to the abnormal formation of collagenous structures in blood vessels. 

Ellipsometry is useful in examining the behavior of enzymes on electrodes. Another excellent tool is the atomic force microsope (Section 7.5.18). Eppel (1993) used AFM to examine the absorption of a glycoprotein on some biosurfaces (AFM does not need conduction electrons to function), and was able to measure its elliptical cross section in the absorbed state. It was possible to map changes in the charge density of the protein (which plays a role in thrombus formation in arterial blockage) upon absorption by the change in the height of various parts of the molecule. This is an excellent example of the detail in which absorbed species can be examined. 

When most people think about the arteries at all, it s in terms of plumbing. The arteries are simply pipes, conduits, for blood flow. Problems occur when those pipes get clogged, although not in the simplistic way that s commonly imagined. The plaque, as arterial blockage is properly termed, doesn t accumulate on the inner walls of the arteries the way calcium builds up on bathroom plumbing. Rather, it s a complex process that develops inside the layers of the walls of those arteries. 

The Baylor doctors reported in 1967 a case of right vertebral artery blockage. The vertebral arteries are small, extremely important, and totally inaccessible blood vessels that travel from the heart, up the back of the spinal column, to the back of the brain. If one or both of these arteries become blocked you are in deep trouble. You lose speech, vision, and balance. Some victims of this type of blockage have "drop attacks." They drop to the floor just as if someone had cut their legs from under them. This happens without the slightest loss of consciousness. An inexperienced doctor will think the patient is faking because of the lack of mental change with the episode. It is a peculiar and mysterious medical phenomenon. 

Summarize how "cold" areas in thallium-201 scans could correspond to artery blockages. 

A double-blind, placebo-controUed, prospective trial [37] enrolled 97 patients with diabetes in whom angiography had revealed coronary artery blockages. The patients were randomized to either a loading dose of 8 mg of rosiglitazone before angiography and stent placement, followed by 4 mg of rosiglitazone for 6 months or placebo on the same schedule. At the end of the 6-month period. 

The effect of fats and oils on health has been widely debated. Some diets call for drastic reduction of daily intake of fats and oils whereas other diets actually call for an increase in fats and oils. The Food and Drug Administration (FDA) recommends that fats and oils compose less than 30% of total caloric intake. However, because fats and oils have a higher caloric content per gram than other food types, it is easy to eat too much of them. The FDA also recommends that of those fats that are consumed, no more than one-third (10% of total caloric intake) should be saturated fats. This is because a diet high in saturated fats increases the risk of artery blockages that can lead to stroke and heart attack. Monounsaturated fats, by contrast, may help protect against these threats. 

Thromboangitis obliterans is arterial blockage caused by the inflammation and fibrosis of the connective tissue that surrounds the medium-sized arteries and veins. 

Special small ultrasound transducers, often referred to as endoscopic transducers, have been designed which can be inserted into blood vessels to examine blockages in arteries (43). These transducers operate at approximately 20 MHz and have a viewing distance of less than a centimeter. Such devices are capable of producing ultrasound images of the inside of arteries and veins. The quaUty of the ultrasound image is sufficient to determine the type of blockage. 

Fig. 5. In coronary bypass, an autologous saphenous vein is used to provide critical blood to the heart muscle, bypassing a blockage in the coronary artery.

Meticulous care needs to be used in the application of this tissue adhesive. Only a very thin layer of adhesive should be used to assist with reapproximation of the intima and adventitia. It is important to remember that the material should not be allowed to drip into or onto critical areas such as the ostium of the coronary arteries. Inadvertent placement of this agent in such areas can result in blockage of a critical artery and a potentially fatal myocardial infarction. In addition. 

Papaverine is an opium alkaloid initially isolated in the mid-1800s. It relaxes smooth muscle and is a potent vasodilator. As such it is used to dilate pulmonary and other arteries. It is therefore sometimes of use in the treatment of angina pectoris (usually caused by partial blockage of the coronary artery), heart attacks and bronchial spasms. 

Our most common lethal disease is atherosclerosis, which causes constriction and blockage of arteries of the heart, brain, and other organs. In the United States, Europe, and Japan half of all deaths can be attributed to this ailment.a,b There seems to be a variety of causes. However, there is agreement that the disease begins with injury to the endothelial cells that form the inner lining of the arteries.3/C/d This is followed by the aggregation of blood platelets at the sites of injury and infiltration of smooth muscle cells, which may be attracted by 12-hydrox-yeicosotetraenoic acid and other chemoattractants formed by activated platelets.c "Foam cells" laden with cholesterol and other lipids appear, and the lesions enlarge to become the characteristic plaques (atheromas). 

Angina pectoris is typically associated with some degree of coronary artery occlusion. To help prevent further blockage of the coronary arteries, certain anticoagulant drugs can be administered so that a partially occluded artery does not become completely... 

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