Takahito Kunimatsu

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It is well known that IL-2 production of CD4(+) T cells from old mice (old T cells) is impaired. In this study, we have examined TCR complex zeta chain expression of old T cells and their TCR downstream signal transduction pathways stimulated with anti-CD3. Activation of protein tyrosine kinases, Fyn and ZAP-70, and turnover of inositol phosphates(More)
We performed real-time monitoring of the extracellular glutamate dynamics in the rat striatum in vivo using the microdialysis electrode technique, during an experimental penumbral condition of moderate global cerebral ischemia and activated glutamate receptors. The local cerebral blood flow (CBF) was measured with a laser-Doppler probe. One minute after(More)
1,5-Anhydro-D-glucitol (1,5-AG) is fairly widespread in food products. It is also one of the major polyols in the human body, and its concentration is homeostatically regulated. We report here on the beneficial effects of 1,5-AG in preventing hyperglycemia and its role in improving metabolic syndrome. The findings revealed that it does not affect blood(More)
Brain hypothermia during ischemia may have a neuroprotective effect on pathological and functional outcomes in vivo. Although a microdialysis study demonstrated that hypothermia decreases glutamate release into the extracellular space, the issue of whether this suppression of the glutamate elevation normally accompanying ischemia is attributable to(More)
Whereas a 2-3 degrees C decrease in intraischemic brain temperature can be neuroprotective, mild brain hyperthermia significantly worsens outcome. Our previous study suggested that an ischemic injury mechanism which is sensitive to temperature may not actually increase the extracellular glutamate concentration ([Glu](e)) during the intraischemic period, but(More)
Our newly developed method using a dialysis electrode has made it possible to perform real time monitoring of extracellular glutamate concentration ([Glu]e) utilizing the oxygen-independent reaction with glutamate oxidase and ferrocene. In this study, we therefore, investigated [Glu]e changes during brain ischemia using both the conventional microdialysis(More)
Increased extracellular glutamate ([GLU]e), under the condition of cerebral ischemia, anoxia or hypoxia, has been recognized as being associated with neuronal cell damage and death. We performed real-time monitoring of [GLU]e dynamics in vivo in the rat striatum during systemic acute anoxia or hypoxia, as well as monitoring the direct current potential (DC)(More)
The Ho crossed aldol condensation provides access to a series of carbon branched iminosugars as exemplified by the synthesis of enantiomeric pairs of isoDMDP, isoDGDP, and isoDAB, allowing comparison of their biological activities with three linear isomeric natural products DMDP, DGDP, and DAB and their enantiomers. L-IsoDMDP(More)
Using a dialysis electrode, previous studies showed a clear biphasic release of glutamate during anoxia and ischemia. In this study, we examined two hypotheses: (1) glutamate is of vesicular origin and its release is thus Ca2+- and ATP-dependent in the first phase, while in the second phase glutamate is derived primarily from the metabolic pool, and (2)(More)
Numerous reports have suggested that anoxic depolarization is a critical event in the pathogenesis of cerebral ischemia. Extracellular glutamate concentration ([Glu]e) is closely related to the pathogenesis of ischemia. Therefore, these pathogenic mechanisms merit study, especially the relationship between [Glu]e elevation and the ionic basis of early(More)