Vascular fragility

Hickey M, Dwarte D, Fraser IS. Superficial endometrial vascular fragility in Norplant users and in women with ovulatory dysfunctional uterine bleeding. Hum Reprod 2000 15(7) 1509-14. 

Vascular fragility may also result from reduced sulfation of proteoglycans in connective tissue, as may also occur in hyperhomocysteinemia (Section 10.3.4.2). Dehydroascorbate catalyzes the oxidation of homocysteine to ho-mocysteic acid, which is the precursor of PAPS, the sulfate donor for sulfation reactions (McCuUy, 1971). 

Vascular fragility may aiso result from reduced sulfation of proteoglycans in connective tissue, as may aiso occur in hyperhomocysteinemia (Section... 

Homocysteine Increase of vascular fragility, loss of endothelium, proliferation of smooth muscle cells promotion of atheroma formation Atherosclerosis synthesis... 

Vascular access ports typically consist of a self-sealing siUcone septum within a rigid housing which is attached to a radiopaque catheter (see Radiopaques). The catheter must be fabricated from a low modulus elastomeric polymer capable of interfacing with both soft tissue and the cardiovascular environment. A low modulus polyurethane-based elastomer is preferred to ensure minimal trauma to the fragile vein. 

Copper is an essential component of numerous key metalloenzymes which are critical in melanin formation, myelin formation and crosslinking of collagen and elastin. Copper plays a vital role in hemopoiesis, maintenance of vascular and skeletal integrity, and structure and function of the nervous system. Thus a deficiency of copper can lead to a variety of adverse effects such as increased fragility in bones, aneurysm formation in arteries and a loss of lysyl oxidase activity in cartilage.54 57 Articles on copper also appear in Siget1, volumes 3 and 5, all of volumes 12 and 13, and volume 14,... 

Other mutations of fibrillar collagen, or mutations that affect collagen-processing, cause Ehlers-Danlos syndrome (EDS), a group of heritable connective tissue disorders causing skin hyperextensibility, articular hypermobility, and tissue fragility. The 3 major types are classic (EDS-I and EDS-II), hypermobility (EDS-III) and vascular (EDS-IV). 

Vascular EDS, (EDS-IV fragile blood vessels) is exclusively associated with mutations of COL3A1, the gene encoding type HI collagen (Table 3.1). Most mutations (66%) are substitutions of glycine for another amino acid in one of the gly-X-Y triplets and nearly all the rest are the result of exon skipping. 

EDS VIII is associated with aggressive periodontal disease. It may be caused by a mutation in one or more genes other than the collagen gene (COL2A1) on chromosome 12. Individuals resemble Marfan s syndrome (Table 6.1), but have normal teeth. They display excessive bleeding around the knees and fragile skin, hallmarks of vascular EDS. 

KI + iodine (Lugol s solution) possible use in thyrotoxicosis used preoperatively, —>4 gland size, fragility, and vascularity... 

Flavones and flavonoids - This group includes heterocyclic compounds, uneasily dissolved in water. Flavones and their derivatives have a yellow color, due to which they obtained their name (flavum=yellow). These compounds (rutin, quercetin, hesperidin, citrin and others) have the ability to decrease the permeability of vascular walls and fragility of capillary walls, have antispasmodic actions used for spasms of vessels and smooth-muscle organs, and are used to treat stomach and duodenal ulcers, and hepatitis. 

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