| Project/Area Number |
07670027
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
General anatomy (including Histology/Embryology)
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| Research Institution | UNIVERSITY OF THE RYUKYUS |
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Principal Investigator |
HIRATA Yukio UNIVERSITY OF THE RYUKYUS/FACULTY OF MEDICINE/PROFESSOR, 医学部, 教授 (70073070)
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| Co-Investigator(Kenkyū-buntansha) |
YAMAGUCHI Keiichiro ibid./ibid./ASSOCIATE PROFESSOR, 医学部附属病院, 助教授 (40210356)
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| Project Period (FY) |
1995 – 1996
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| Project Status |
Completed (Fiscal Year 1996)
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| Budget Amount *help |
¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1996: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1995: ¥400,000 (Direct Cost: ¥400,000)
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| Keywords | HUMAN CHILDREN / BRAIN / WHITE MATTER / DEVELOPMENT / MRI / MYELINATION / BIREFRINGENCE / ヒト胎児・新生児 / 脳組織 / 磁気共鳴断層撮像MRI / 遮光性 / ヒト / 胎児 / MRI |
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| Research Abstract |
The formalin-fixed brains from the autopsy cases of the new born and children were examined 1.5T MRI.Then the brains were either embedded in celloidine for myelin stain or cut on freezing microtome to analyze birefringent structures by crossed Nicol system.
The maturation degrees of the developing brains as assessed morphologically by the stainability of myelinated fibers in the forebrain and the way of birefringence of the white matter were compared with that obtained by MRI.
1. The presence of myelinated fibers becomes detectable earlier by crossed Nicol observation than by the stainability with conventional myelin stain.
2. By rotating the polarizer of the crossed Nicol system, we can differentiate the structural birefringence of parallel nerve fibers in early myelination stage from the intrinsic birefringence of mature myelin sheath which is not influence by the direction of the polarizer.
3. The nerve fascicles with rather mature myelin sheath are distinguished in T1 weighted MRI as the area of low signal intensity from the surrounding zone of rather high intensity corresponding the fibers at early myelination stage.
4. The medulla in front of the anterior horn of the lateral ventricle or the medulla under the prefrontal cortex and the posterior part of the centrum semiovale overlying the posterior horn of the lateral ventricle show progressive changes in their MRI images with the lapse of the postnatal months. These areas appear first heterogeneous in their signal intensity seemingly expressing the heterosynchrony of myelination process among constituent fiber systems (projection fibers vs. association ones, e. g.) but becomes homogeneous with further progress of the late myelination during postnatal growth.
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