We have undertaken studies to identify amino acid residues that are involved in the catalytic mechanism of argininosuccinate synthetase [L-citrulline:L-aspartate ligase (AMP-forming), EC 6.3.4.5] and have found that a cysteine residue and an arginine residue are required for activity. The reactive cysteine residues are accessible to solvent and available to react with 5,5'-dithiobis(2-nitrobenz...

Reactive arthritis is associated with demonstrable infection at a distant site without evidence of sepsis at the affected joint(s). We present a rare case reactive arthritis where no bacterial or chlamydial infections could be established, rather larvae of Strongyloides stercoralis could be demonstrated in the stool and duodenal biopsy. Reactive arthritis, psoriasiform lesions and malabsorption...

Dasatinib was approved in 2006 for the treatment of imatinib-resistant chronic myelogenous leukemia and functions primarily through the inhibition of BCR-ABL and Src kinase. Dasatinib is extensively metabolized in humans by CYP3A4. In this study, we report that the bioactivation of dasatinib by CYP3A4 proceeds through a reactive intermediate that leads to CYP3A4 inactivation with K(I) = 6.3 mic...

Eight hundred and three samples from a single HCV antibody negative diagnostic population were tested on the Abbott ARCHITECT HCV Ag assay. All samples initially reactive were retested in duplicate. Samples repeatedly reactive were tested for HCV RNA to determine the true status. Samples that were confirmed as positive were excluded from the specificity and negative delta calculations. A total ...

The effects of adenosine and adenosine analogs on adenylate cyclases from several tissues have been examined. Two adenosine-reactive sites have been identified: (i) the "R" site, occupancy of which usually leads to activation of cyclase and which requires integrity of the ribose ring for activity, and (ii) the "P" site, which mediates inhibition and requires integrity of the purine ring for act...

The goal of the innate immune system is containment of a pathogen at the site of infection prior to the initiation of an effective adaptive immune response. However, effector mechanisms must be kept in check to combat the pathogen while simultaneously limiting undesirable destruction of tissue resulting from these actions. Here we demonstrate that innate immune effector cells contain a peripher...

The amino acid sequences of garden bean (Phaseolus vulgaris) trypsin inhibitor II and a related molecular species II' have been examined. The entire sequence of II' has been determined with the exception of five internal residues. The garden bean inhibitors are highly homologous to the Bowman-Birk soybean inhibitor and lima bean trypsin inhibitor IV. The trypsin-reactive site has been located i...

Ambient concentrations of reactive nitrogen compounds as well as total NO, were measured during June and early July 1992 at a rural site, site SONIA, in the central Piedmont region of North Carolina as a part of the Southern Oxidants Study. The measurements of reactive nitrogen species were made in an effort to provide a comprehensive understanding of nitrogen chemistry and to investigate the t...