Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.2.1.1 (ACS)
 78,556 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recently, highly sensitive prostate specific antigen (PSA) kits have been developed and reported to be useful for the early identification of a chemical relapse. However, if the measurement time was short and the cost low, such an assay kit should be sufficient for cancer screening when dealing with a large number of samples. The One Step PSA test uses an immunochromatographic method to qualitatively, not quantitatively, judge a positive or negative result. We confirmed the sensitivity of the kit using purified PSA. Serum specimens from 147 men with or without prostate diseases were tested using the kit. PSA concentration of each serum specimen was independently measured by a quantitative ACS-PSA2 EIA kit (Chiron, cut-off: 2.1 ng/ml). The sensitivity of this kit was determined to be 4 ng/ml. All 33 samples with a value of greater than 4 ng/ml were clearly positive. Of the 94 samples with values less than 4 ng/ml, nine were judged as positive. The remaining 85 cases were judged as completely negative. These results indicate that the sensitivity of the One Step PSA test is 100% and the specificity is 90.4%. Tests using this kit can be easily performed at outpatient clinics or elsewhere. This kit is useful for initial cancer screening, because results can be obtained within 15 min and at a cost lower than that of ordinary PSA kits.
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PMID:Evaluation of a rapid qualitative prostate specific antigen assay, the One Step PSA(TM) test. 1114 17

Nonequimolar-response assays for prostate-specific antigen (PSA) are criticized for overestimating total PSA in some men without prostate cancer (PCA), and underestimating total PSA in some men with PCA. We recently studied three nonequimolar-response PSA assays that had undergone modifications. While two of the studied assays achieved equimolar-response characteristics with improved areas under receiver operating characteristic (ROC) curves (AUC), the modification of the Chiron ACS PSA assay (ACS PSA2, Chiron) failed to achieve this. Recently, the ACS assay underwent another modification (ACS PSA, Bayer), which we investigated. Sera from 305 men (155 without and 150 with PCA, PSA > or = 2 and < or = 30 microg/l, Tandem-E) were measured using both modifications of the ACS assay and equimolar-response reference methods (Tandem-R free and Tandem-E, Hybritech). Molar response relative to the reference method and clinical performance (comparison of AUCs) between the previous and new ACS assay modifications were studied. The new modification of the ACS assay (ACS PSA, Bayer) achieved equimolar-response characteristics but reported lower values (average 10%) than the Tandem-E assay. Compared to the previous modification (ACS PSA2, Chiron), a 3% improvement in AUC (p = 0.01) was found. Using results of the redesigned equimolar-response assay (ACS PSA, Bayer), we calculated that 6 of 155 men without PCA in this sample set could be spared unnecessary biopsy compared with the previous nonequimolar-response assay (ACS PSA2, Chiron) without missing additional PCA (90% sensitivity). These data provide additional evidence for clinical advantages of equimolar-response over nonequimolar-response PSA assay formats.
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PMID:A new modification of the Chiron ACS assay for total prostate-specific antigen achieves equimolar response characteristics and improves the detection of prostate cancer. 1263 56