- 著者
- Hiroyuki TAKAO Dai WATANABE Satoshi TANI Hiroki OHASHI Tosihiro ISHIBASHI Kohei TAKESHITA Shigeyuki MURAKAMI Tetsuya NISHIMOTO Kohei YUGE Kostadin KARAGIOZOV Toshiaki ABE Yuichi MURAYAMA
- 出版者
- The Japan Neurosurgical Society
- 雑誌
- Neurologia medico-chirurgica (ISSN:04708105)
- 巻号頁・発行日
- pp.oa.2021-0149, (Released:2021-10-14)
- 参考文献数
- 18
- 被引用文献数
- 1
A simulation model was developed to better understand the mechanisms of brain injuries in sports. A three-dimensional model comprising approximately 1.22 million elements was constructed from cranial computed tomography images of adult male volunteers by the voxel method. To simulate contact sports that permit actions such as tackling, a sinusoidal wave with duration of 10 ms and maximum acceleration of 2000 m/s2 was applied to the lowest point of the model to apply rotational acceleration to the head from different directions. The von Mises stress was then observed at five points in the coronal plane of the brain: cingulate gyrus (CG), corpus callosum (CC), brain stem (BS), lateral temporal lobe (LT), and medial temporal lobe (MT). LS-DYNA universal finite element analysis software with explicit time integration was used for the analysis. Concentrations of stress started to appear in the CC and BS at 10 ms post-impact, after which they also became evident in the CG and MT. The maximum changes in stress at each location occurred 10–15 ms post-impact. The von Mises stress was 9–14 kPa in the CG, 8–24 kPa in the CC, 12–24 kPa in the BS, 7–12 kPa in the LT, and 12–18 kPa in the MT. The highest stress in every part of the brain occurred after lateral impact, followed by oblique impact and sagittal impact. Such simulations may help elucidate the mechanisms of brain injuries in sports and help develop measures to prevent chronic traumatic encephalopathy.
- 著者
- Tetsuya Okazaki Kaori Adachi Kaori Matsuura Yoshitaka Oyama Madoka Nose Emi Shirahata Toshiaki Abe Takeshi Hasegawa Toshiro Maihara Yoshihiro Maegaki Eiji Nanba
- 出版者
- Tottori University Medical Press
- 雑誌
- Yonago Acta Medica (ISSN:13468049)
- 巻号頁・発行日
- vol.64, no.1, pp.30-33, 2021 (Released:2021-02-22)
- 参考文献数
- 13
- 被引用文献数
- 4
Background Fragile X syndrome (FXS) is a well-known X-linked disorder clinically characterized by intellectual disability and autistic features. However, diagnosed Japanese FXS cases have been fewer than expected, and clinical features of Japanese FXS patients remain unknown.Methods We evaluated the clinical features of Japanese FXS patients using the results of a questionnaire-based survey.Results We presented the characteristics of seven patients aged 6 to 20 years. Long face and large ears were observed in five of seven patients. Macrocephaly was observed in four of five patients. The meaningful word was first seen at a certain time point between 18 and 72 months (median = 60 months). Developmental quotient or intellectual quotient ranged between 20 and 48 (median = 29). Behavioral disorders were seen in all patients (autistic spectrum disorder in six patients, hyperactivity in five patients). Five patients were diagnosed by polymerase chain reaction analysis, and two patients were diagnosed by the cytogenetic study. All physicians ordered FXS genetic testing for suspicious cases because of clinical manifestations.Conclusion In the present study, a long face, large ears, macrocephaly, autistic spectrum disorder, and hyperactivity were observed in almost cases, and these characteristics might be common features in Japanese FXS patients. Our finding indicated the importance of clinical manifestations to diagnosis FXS. However, the sample size of the present study is small, and these features are also seen to patients with other disorders. We consider that genetic testing for FXS should be performed on a wider range of intellectually disabled cases.