Regulation of the lysophosphatidylserine and sphingosine 1-phosphate levels in autologous whole blood by the pre-storage leukocyte reduction.

BACKGROUND AND OBJECTIVES: The effect of leukoreduction and storage periods on the accumulation of bioactive lysophospholipids and substances in human autologous blood (AB units) has not been fully investigated. MATERIALS AND METHODS: The accumulation of bioactive lysophospholipids such as sphingosine 1-phosphate (S1P) and lysophosphatidylserine (LysoPS) in AB units during the storage was investigated. The time-dependent changes and the effect of the filtration in pre-storage leuckoreduction (LR) and unmodified samples derived from 46 AB units were analysed. Additionally, the changes of lysophospholipids and platelet releasate, namely ß-thromboglobulin (ß-TG), induced by exposure of whole blood (WB) or platelet-rich plasma (PRP) to the filter material were analysed. RESULTS: LysoPS, but not S1P levels, time-dependently and significantly increased in both unmodified and LR samples. LysoPS significantly decreased in LR compared with unmodified samples, whereas S1P increased in LR compared with unmodified samples. In addition, exposure of WB and/or PRP to the filter material in vitro resulted in increased levels of S1P, LysoPS and ß-TG. CONCLUSIONS: LR effectively reduced the accumulation of LysoPS in AB units. On the other hand, it increased concentrations of S1P due to platelet activation by exposure to the filter material. These suggest that increases of S1P levels in LR and LysoPS in the unmodified samples were mainly caused by the leukocytes and/or platelets and that LR was effective in inhibiting the accumulation of LysoPS.

Note: Application of CR-39 plastic nuclear track detectors for quality assurance of mixed oxide fuel pellets.

A CR-39 plastic nuclear track detector was used for quality assurance of mixed oxide fuel pellets for next-generation nuclear power plants. Plutonium (Pu) spot sizes and concentrations in the pellets are significant parameters for safe use in the plants. We developed an automatic Pu detection system based on dense α-radiation tracks in the CR-39 detectors. This system would greatly improve image processing time and measurement accuracy, and will be a powerful tool for rapid pellet quality assurance screening.

New micro-flow pumping system for liquid chromatography.

This paper deals with the development of practical approaches to a new liquid-delivery system for capillary liquid chromatography. Under different chromatographic conditions, the factors affecting liquid-delivery performance are theoretically described, and the new liquid-delivery system without any splitter is evaluated with its flow-rate accuracy and precision using a variety of solvents. The experimental results demonstrate that the liquid-delivery system is capable of generating accurate, reproducible and conditions-independent micro- and nano-flows.

On-line coupling of solid-phase extraction to gas chromatography with fast solvent vaporization and concentration in an open injector liner. Analysis of pesticides in aqueous samples.

The purpose of this study is to combine solid-phase extraction (SPE) with gas chromatography (GC) for the fully automated determination of pesticides and herbicides in aqueous samples. The interface technique employed for connecting SPE with GC was fast solvent vaporization and concentration in an open injector liner. The interface device consisted of the programmed-temperature vaporizing injector without using the packing material in the liner and the target compounds were concentrated around the inlet of the GC capillary column. This avoided the degradation of target compounds, and no precise control of the injecting speed was required, when an automatic SPE system was connected to GC-MS. The aqueous samples used in this system were prepared by spiking 29 kinds of pesticide and herbicide compounds, which are regulated by the Ministry of Health and Welfare of the Japanese National government, in purified water and river water, to a resulting concentration of 1 microg/l. Employing this system, the recoveries and RSDs (n=6) of most compounds were greater than 75% and within 10%, respectively. From the results of this study, we found that on-line automatic SPE and capillary GC-MS equipped with the fast solvent vaporizing and concentrating method in an open injector liner could be connected in order to obtain good results for the determination of pesticides in water samples.

Novel immunochemical characteristics of glutathione S-transferase isozymes of rat liver cytosol.

Reevaluation of the immunochemical relationships among the individual glutathione S-transferase (GST) isozymes (GSTs 1-1, 1-2, 2-2, 3-3, 3-4, 4-4, and GSTs with isoelectric points of 7.5 and 6.8) of rat liver cytosol was performed utilizing the immunoblot technique. As a result, we found that the respective isozymes of two isozyme classes of rat liver cytosol might possess a common epitope(s) which has been undetected by the Ouchterlony double-diffusion method. The assumption was further supported by the results of the effects of Fab' prepared from some anti-GST antibodies on the enzymatic activity of GSTs.