Assignment Of Hexuronic Acid Stereochemistry In Synthetic Heparan Sulfate Tetrasaccharides With 2--Sulfo Uronic Acids Using Electron Detachment Dissociation.

The present work focuses on the assignment of uronic acid stereochemistry in heparan sulfate (HS) oligomers. The structural elucidation of HS glycosaminoglycans is the subject of considerable importance due to the biological and biomedical significance of this class of carbohydrates. They are highly heterogeneous due to their non-template biosynthesis.

The residue mass of L-pyrrolysine in three distinct methylamine methyltransferases.

Single in-frame amber (UAG) codons are found in the genes encoding MtmB, MtbB, or MttB, the methyltransferases initiating methane formation from monomethylamine, dimethylamine, or trimethylamine, respectively, in certain Archaea. The crystal structure of MtmB demonstrated that the amber codon codes for pyrrolysine, the 22nd genetically encoded amino acid found in nature. Previous attempts to visualize the amber-encoded residue by mass spectrometry identified only lysine, leaving information on the existence and structure of pyrrolysine resting entirely on crystallography of a single protein.

Mass Spectrometry for the Analysis of Highly Charged Sulfated Carbohydrates.

Sulfated polysaccharides and their oligosaccharide components play an important biological role in physiological and pathophysiological processes. Glycosaminoglycans, such as heparin, are currently used as pharmaceutical agents to control coagulation. Moreover, there arc intensive efforts in developing rapid approaches for the analysis of such bioactive carbohydrates to assess their pharmacological activity and in glycomic applications.

Idiopathic cerebral infarction and upper limb ischemia in neonates.

Idiopathic cerebral infarction is very rare in neonates and has been described as being associated with upper extremity ischemia in a handful of cases. We report on two cases in which no etiology was found and review the literature on this interesting entity.

MRI of trauma and sports-related injuries of tendons and ligaments. Part I: Spine and upper extremities.

MRI is valuable in evaluation of tendons and ligaments in sports-related injuries. Tendons and ligaments show dark signal intensity on all MR sequences. Alteration in size, shape, continuity, and signal intensity of these structures can be well visualized with MRI.