Human leukocyte antigen (HLA)-G exhibits immunotolerogenicity and is related to allograft acceptance. Qa-2 is the murine homolog of HLA-G; it has structure and functions similar to those of HLA-G. We investigated the dynamic expression of Qa-2 in skin allografts by immunohistochemistry and on peripheral blood lymphocyte subsets by flow cytometry during the entire process of acute graft rejectio...

PURPOSE This report describes the value of a voluntary error reporting system and the impact of a series of quality assurance (QA) measures including checklists and timeouts on reported error rates in patients receiving radiation therapy. METHODS AND MATERIALS A voluntary error reporting system was instituted with the goal of recording errors, analyzing their clinical impact, and guiding the ...

IMRT QA requires, among other tests, a time-consuming process of measuring the absorbed dose, at least to a point, in a high-dose, low-dose-gradient region. Some clinics use a technique of measuring this dose with all beams delivered at a single gantry angle (collapsed delivery), as opposed to the beams delivered at the planned gantry angle (rotated delivery). We examined, established, and opti...

Quality assurance (QA) is the total process whereby the quality of laboratory reports can be guaranteed. The term quality control covers that part of QA, which primarily concerns the control of errors in the performance of tests and verification of test results. All materials, equipment and procedures must be adequately controlled. Culture media must be tested for sterility and performance. Eac...

Some of the tryptophan catabolites produced through the kynurenine pathway (KP), and more particularly the excitotoxin quinolinic acid (QA), are likely to play a role in the pathogenesis of Alzheimer's disease (AD). We have previously shown that the KP is over activated in AD brain and that QA accumulates in amyloid plaques and within dystrophic neurons. We hypothesized that QA in pathophysiolo...

Immunological and biochemical characteristics of the Qa-2 murine nonclassical histocompatibility class 1 antigen expressed on tumor cells derived from H-2k (Qa-2-) mice were studied. It was found that the Qa-2 antigen on normal H-2b lymphocytes reacted with Qa-2-specific monoclonal antibodies (mAbs) 34-1.2, 59 (both specific to the alpha 1/alpha 2 region) and 141-15.8 (specific to the alpha 3 d...

Quinolinic acid (QA) is a potent endogenous excitotoxin; elevation of its concentration in an organism has been implicated in the pathogenesis of various disorders. The purpose of this study was the assessment of QA impact on the process of erythropoiesis. Marked increase of QA concentration was observed in plasma and peripheral tissues of uremic rats. These changes were proportional to the amo...

Extracts of 125I-labeled cloned murine cytotoxic T lymphocytes (CTL) were immunoprecipitated with alloantisera to the cloned CTL and rabbit antisera to beta-2 microglobulin. Polyacrylamide gel electrophoresis (PAGE) of the specific precipitates revealed, as expected, 125I-labeled components that corresponded to products of class I genes of the major histocompatibility complex (MHC). However, ad...