Background: The timing of the cell division in Escherichia coli is highly regulated, but its mechanism has not been identified. Previously we have found that the cfcA1 mutation uncouples DNA replication and cell division and elevates the frequency of cell division. We further analysed the structure and the role of the cfc genes of cfcA11, a derivative of cfcA1, and another cfc mutant, cfcB1.

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Liposome-encapsulated hemoglobin (LEH) is removed from the circulation and degraded in the reticuloendothelial system, including dendritic cells (DCs) and macrophages. Therefore, LEH at a large dose may overload the system, cause a competitive inhibition in antigen-presenting activity, and impair the immune response of the host. Changes in cellularity of immunocompetent cells were monitored serially up to 4 weeks by flow cytometry in wild-type mice receiving 20 mL/kg of LEH, syngeneic red blood cells (RBCs), or saline. DCs were collected from the host spleen 1, 7, and 28 days after receiving the solution and were cocultured with naïve cluster of differentiation 4 T cells from T-cell receptor transgenic mice in the absence or presence of third-party antigens. After LEH administration, the cellularity of DCs and macrophages in the recipient spleen remained unchanged from control mice receiving RBCs or saline. While subset populations and costimulatory molecule expressions were different, DCs from LEH-administered mice expressed high levels of interleukin-2 production and helper T-cell activation in response to a third-party antigen and superantigens, as did the DCs from control mice receiving RBCs or saline. The results suggest that 20 mL/kg of LEH does not greatly alter antigen-presenting activity to third-party antigens.

Quantitative NMR (qNMR) is applied to determine the absolute quantitative value of analytical standards for HPLC-based quantification. We have previously reported the optimal and reproducible sample preparation method for qNMR of hygroscopic reagents, such as saikosaponin a, which is used as an analytical standard in the assay of crude drug section of Japanese Pharmacopoeia (JP). In this study, we examined the absolute purity determination of a hygroscopic substance, indocyanine green (ICG), listed in the Japanese Pharmaceutical Codex 2002, using qNMR for standardization by focusing on the adaptation of ICG to JP. The purity of ICG, as an official non-Pharmacopoeial reference standard (non-PRS), had high variation (86.12 ± 2.70%) when preparing qNMR samples under non-controlled humidity (a conventional method). Additionally, residual ethanol (0.26 ± 0.11%) was observed in the non-PRS ICG. Next, the purity of non-PRS ICG was determined via qNMR when preparing samples under controlled humidity using a saturated sodium bromide solution. The purity was 84.19 ± 0.47% with a lower variation than that under non-controlled humidity. Moreover, ethanol signal almost disappeared. We estimated that residual ethanol in non-PRS ICG was replaced with water under controlled humidity. Subsequently, qNMR analysis was performed when preparing samples under controlled humidity in a constant temperature and humidity box. It showed excellent results with the lowest variation (82.26 ± 0.19%). As the use of a constant temperature and humidity box resulted in the lowest variability, it is recommended to use the control box if the reference ICG standard is needed for JP assays.