Cause and Laboratory Diagnosis

The cause of the arthrochalasis type of EDS is the result of mutations leading to loss of exon 6, or part of it, of the mRNA coding for one of the a1 chains (EDS type VIIA) or for the a2 chain (EDS type VIIB) of type I collagen.[18] This exon-skipping mutation leads to the loss of the amino-terminal telopeptide, which links the N-propeptide to the main, triple-helical domain. This N-telopeptide contains the N-proteinase cleavage site as well as the critical cross-linking lysyl residue and the cleavage sites for proteinases such as pepsin and a-chymotrypsin. Hence, lack of this segment leads to deficient processing of the N-propeptide of type I collagen. The biochemical confirmation of the diagnosis is based on electrophoretic demonstration of pNa1(I) (type A) or pNa2(I) (type B) chains of collagen type I extracted from dermal collagen or harvested from cultured skin fibroblasts. Molecular analysis can be performed to confirm the biochemical

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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