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Kindling-induced after discharge in electroencephalograms depends on the protein associated with glutamatergic and/or GABAergic neuronal transmission. In glutamate transporter knockout (GLAST KO) mice, the kindling phenomena in GLAST KO developed more slowly while the after discharge duration (ADD) was briefer than that of the control C57BL-6J mice. These findings indicate that either the excitatory function was suppressed or the inhibitory function was enhanced in GLAST KO kindling. To explain these phenomena, we used Western blotting to evaluate the alterations in the expression of hippocampal GABA transporter proteins, and the estimation of the effect on the process of epileptogenesis. Although no alterations were observed in the GAT-3 expression, the hippocampal GAT-1 expression was significantly suppressed in comparison to that of C57BL-6J mice. A decreased GAT-1 level in the hippocampus, which might be associated with the increased extracellular GABA level, may therefore inhibit both ADD and seizure propagation as shown by the amygdaloid kindling phenomenon observed in GLAST KO mice. 相似文献
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Takaki M Ueda Y Doi T Nagatomo K Murashima YL Nakajima A Kannan H 《Neuroscience research》2007,58(3):336-338
Electron spin resonance (ESR) spectroscopy combined with in vivo microdialysis was used to analyze the antioxidant ability in the hippocampus of mice in an interictal state of EL mice utilizing decay ratio of an exogenously applied nitroxide radical (3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCAM)). In EL mice with a history of frequent seizures, the half-life of the electron paramagnetism of PCAM in the hippocampus was prolonged. These results revealed decreased antioxidant ability, suggesting vulnerability against oxidative stress. Our data suggest that epileptogenesis in EL mice with chronic seizures is associated with functional failure due to the oxidized redox state and revealed that the decreased hippocampal antioxidant ability is related to the regional vulnerability to oxidative stress in the limbic system of EL mice during epileptogenesis. 相似文献
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Horiguchi S Matsuoka T Okamoto Y Sakurai D Kobayashi K Chazono H Hanazawa T Tanaka Y 《Journal of clinical immunology》2007,27(6):598-604
Tumor-specific peptide-pulsed dendritic cells (DC) were administered via different routes to a group of patients with head
and neck cancers. The migration and homing patterns of such antigen-stimulated cells was carefully studied employing single
photon emission computed tomography (SPECT). The DC administered directly into the nasal submucosa quickly migrated very rapidly
to the regional neck lymph nodes in the neck. However, after inoculation of the cells into the palatine tonsils, the DCs remained
close to the site of administration and did not migrate to the regional lymph nodes or to other mucosal regions. After nasal
submucosal administration of the DC, tumor-antigen-specific cytotoxic T cells were detected in the ipsilaterals but not in
the contra lateral lymph nodes. These results suggest that after antigen processing, the regional lymph nodes serve as inductive
sites for development of mucosal immune responses and for induction of memory cells during the local immunological responses
in the nasopharyngeal-associated lymphoid tissue in man. 相似文献
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Annegret Wuensch Petra Kameritsch Riccardo Sfriso Eva-Maria Jemiller Andrea Bähr Mayuko Kurome Barbara Kessler Elisabeth Kemter Christian Kupatt Bruno Reichart Robert Rieben Eckhard Wolf Nikolai Klymiuk 《Xenotransplantation》2020,27(5):e12585
The activation of the endothelial surface in xenografts is still a poorly understood process and the consequences are unpredictable. The role of Ca2+-messaging during the activation of endothelial cells is well recognized and routinely measured by synthetic Ca2+-sensitive fluorophors. However, these compounds require fresh loading immediately before each experiment and in particular when grown in state-of-the-art 3D cell culture systems, endothelial cells are difficult to access with such sensors. Therefore, we developed transgenic pigs expressing a Ca2+-sensitive protein and examined its principal characteristics. Primary transgenic endothelial cells stimulated by ATP showed a definite and short influx of Ca2+ into the cytosol, whereas exposure to human serum resulted in a more intense and sustained response. Surprisingly, not all endothelial cells reacted identically to a stimulus, rather activation took place in adjacent cells in a timely decelerated way and with distinct intensities. This effect was again more pronounced when cells were stimulated with human serum. Finally, we show clear evidence that antibody binding alone significantly activated endothelial cells, whereas antibody depletion dramatically reduced the stimulatory potential of serum. Transgenic porcine endothelial cells expressing a Ca2+-sensor represent an interesting tool to dissect factors inducing activation of porcine endothelial cells after exposure to human blood or serum. 相似文献
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Jun Deguchi Kaori Horiguchi Chin Piow Wong Takahiro Hosoya Akane Iihoshi Toshio Kaneda Hiroshi Morita 《Journal of natural medicines》2014,68(4):723-729
Previously, we reported the isolation of cassane-type diterpenes, sucutiniranes A–F, from the seeds of Bowdichia nitida. In this study, a series of sucutinirane derivatives was prepared, and their in vitro toxicity in the HL-60 cell line was evaluated. Then the action mechanism of a representative compound that induces cell death was investigated. Whereas C-6 or C-7 diol esters and ether decreased the activity against the HL-60 cell line, furan-oxidized derivatives 12 and 13 showed improvement or retention of the activity compared with those of the natural products sucutinirane A (11), E (1), and F (2). Treatment with sucutinirane derivative 13 elevated caspase 3/7 activity and also decreased expression of Bcl-2 family proteins, Mcl-1, and Bid. Derivative 13 generated reactive oxygen species in HL-60 cells, whose apoptotic effects were attenuated by the addition of an antioxidant, N-acetyl-l-cysteine. These results suggest that cassane butenolide 13 induces apoptosis in HL-60 via its oxidative effects. 相似文献