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Background: The incidence of Bacillus cereus bacteremia is increasing, but the identification of Bacillus species remains difficult. Brilliance Bacillus cereus agar (BBC agar; Oxoid, UK) is a new CHROMagar medium that allows selective isolation and identification of B. cereus; however, its clinical usefulness is seldom studied. We evaluated the usefulness of BBC agar to identify B. cereus isolates recovered from blood cultures., Methods: We analyzed a total of 53 blood isolates that showed a Bacillus-like morphology on Gram staining. All isolates were identified by using both the API Coryne (bioMérieux, France) and API 50CH/B (bioMérieux) systems. They were subsequently subcultured on BBC agar, incubated for 24 hr, and then examined for characteristic blue-green colonies. The clinical characteristics of patients whose isolates were identified as B. cereus were assessed., Results: Of the 53 isolates, 18 were identified as B. cereus by API 50CH/B. With the API 50CH/B system used as gold standard, the sensitivity and specificity for the identification of B. cereus were 100% (18/18) and 100% (35/35), respectively, using BBC agar, and 67% (12/18) and 100% (35/35), respectively, using the API Coryne system. Of the 18 patients with B. cereus bacteremia, 15 showed infectious signs, and 3 had more than 2 blood cultures positive for B. cereus on separate days., Conclusions: Our study shows, for the first time, that BBC agar, with its good agreement and ease of use, is a valuable alternative to the API 50CH/B system for the presumptive identification of B. cereus isolates from blood cultures.

Background: The aim of our study was to optimize and establish erythropoietin (EPO) enzyme linked immunosorbent assay (ELISA) system., Methods: We prepared several monoclonal and polyclonal antibodies specific to human-EPO. The best combinations of antibodies for coating and detecting antibodies were selected for the establishment of ELISA. We tested several methods such as a competitive EIA and a sandwich ELISA., Results: The best sandwich ELISA was optimized compared to competitive EIA when purified polyclonal antibody (PoAb) was used as a coating antibody and biotinylated PoAb as a detecting antibody. This sandwich ELISA easily detected EPO when PoAb pairs were used compared to the ELISA using monoclonal antibody and PoAb. There were no significant differences between the effects of various blocking solutions on the performance of sandwich ELISA using biotinylated antibody. The ELISA system using PBST containing 3% BSA as a blocking solution can sensitively detect EPO (10 mU/mL) in a broad range of EPO concentrations (10-2,000 mU/mL) and there were cross-reactions with other cytokines)., Conclusions: EPO can be easily determined by using biotinylated PoAb as a detecting antibody and another PoAb as a coating antibody.