| Project/Area Number |
04807071
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Pediatrics
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| Research Institution | Kansai Medical University |
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Principal Investigator |
KINOSHITA Yo Kansai Medical University, Medicine, Assistant Professor, 医学部, 講師 (10105778)
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| Co-Investigator(Kenkyū-buntansha) |
KOHDERA Urara Kansai Medical University, Medicine, Instructor, 医学部, 助手 (90198614)
TANIUCHI Shoichiro Kansai Medical University, Medicine, Assistant Professor, 医学部, 講師 (70171832)
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| Project Period (FY) |
1992 – 1993
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| Project Status |
Completed (Fiscal Year 1993)
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| Budget Amount *help |
¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1993: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1992: ¥800,000 (Direct Cost: ¥800,000)
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| Keywords | F-actin / Neutrophil / Neonate / Cytokine / 新生児好中球 / 好中球運動能 / H_2O_2産生能 / フロ-サイトメトリ- / フローサイトメモリー |
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| Research Abstract |
The increased susceptibility of the neonates to bacterial infections is partly due to developmental deficiencies of polymorphonuclear cells(PMN) chemotaxis and adherence. To elucidate the mechanism of such defects, we determined actin polymerization of NBD-phallacidin stained neutrophils following stimulation either with fMLP(N-formyl-methionyl-leucyl-phenylalanine) or PMA(phorbol myristate acetate) and compared between cord blood and adult controls.
Relative F-actin polymerization, i.e. a ratio of stimulated F-actin to basal F-actin, was significantly decreased in cord PMN when compared to that of adult PMN.Basal F-actin level was significantly higher in cord PMN than adult PMN.F-actin level of cord PMN was significantly diminished when compared with adult at 60s after fMLP stimulation. However cord PMN showed similar stimulated F-actin levels when compared with adult PMN following PMA.we also analyzed histograms of F-actin in cord and adult PMN befere and after a stimulation. Distribution of fMLP stimulated F-actin showed a bimodal pattern, whiled adult PMN disclosed a single pattern. Stimulation with PMA indicated similar patterns in both cord and adult PMN.Preincubation (30min) adult PMN with TNF-alpha or G-CSF resulted in increased basal actin level, however it didn't affect stimulated F-actin level and a pattern following fMLP.In addition no significant difference was observed before and after fMLP and PMA between vaginal and c-section delivery. These results suggest that relative deficiency of F-actin polymerization to fMLP in cord PMN may be explained by both of the priming effect of cytokines and the presence of heterogeneity in PMN.
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