g. 5 × 107CFU) of bacteria in each lane. Determination of the CFU counts An aliquot of tissue homogenate or bacterial culture was used to determine its CFU/ml by serial dilution with PBS and plating on LB agar plates [45,48]. The bacteria were enumberated after overnight incubation. Each sample HSP inhibitor was analyzed in triplicate and the analysis was repeated at least twice. The CFU of the sample

was expressed as the average of the values obtained. The concentrations of bacteria were recorded as CFU/ml of organ homogenate or culture. The limit of bacteria detection in the organ homogenates was 10 CFU/ml. Those samples that were negative at a 10-1dilution were designated a value of 10 (101) CFU/ml. Acknowledgements We thank Gerry Abenes, Cindy Loui, Hongwei Gu, and Huiyuan Jiang for suggestions and excellent technical assistance. Y. Y. was a visiting scientist from State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University (P. R. China). L.M. was a recipient of a China Graduate Student Scholarship from the Ministry of Education of China. K. K. and Y. B. were partially supported by a Block Grant Predoctoral Fellowship (UC-Berkeley). The research has been supported

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