京都大学 大学院医学研究科 人間健康科学系専攻 病理学研究室（形態形成医療科学）

第60回日本先天異常学会で発表しました。（2020.07.11-12, 神戸）

新型コロナウイルス感染症の影響でon line 学術開催となりました。

金橋　徹、山田重人、米山明男、高桑徹也, ヒト胚子期に起こる生理的臍帯ヘルニアの発生要因‐肝形成との関連に基づいた形態及び形態計測学的検討

藤井 瀬菜, 村中 太河, 松林 潤, 米山 明男, 兵藤 一行, 山田 重人, 高桑　徹也, ヒト胚子期における気管支の非対称性の定量的検討

共同研究者の勝部先生、東島先生が奨励賞を受賞しました。おめでとうございます。

勝部　元紀　先生
Critical Growth Processes for the Midfacial Morphogenesis in the Early Prenatal Period
東島　沙弥佳　先生
Tail reduction process during human embryonic development

第125回日本解剖学会で発表しました(3/25-3/27, 山口）

高桑徹也、寺島芽衣、石川葵、山田重人: ヒト胚子期終期における大脳層構造の三次元的解析

藤井瀬菜、村中 太河、松林 潤、米山明男、兵藤一行、山田重人、高桑徹也：ヒト胚子期における気管支形成の定量的解析 

山口豊、村瀬亜美、児玉竜汰、舩冨卓哉、向川康博、高桑徹也、山田重人：ヒト器官形成期における下肢筋骨格系の形態形成過程の三次元可視化 

コロナウイルス感染症のため、学会は抄録集による誌上開催での発表となりました。

第73回日本人類学会で発表しました（2019.10.12-14、佐賀）。

われわれの研究も人類の研究なので、発表してみました。どの程度受け入れられたでしょうか。

ヒト胚子期における気管支分岐形成の三次元的定量解析
藤井 瀬菜、村中 太河、松林 潤、米山 明男、兵藤 一行、山田 重人、高桑 徹也
ヒト胚子期・胎児期初期における気管・軟骨の3次元的解析
山崎 優、藤井 瀬菜、石川 葵、山田 重人、高桑 徹也
Carnegie Stage (CS) でのヒト後腎における腎小体の発生段階と立体的分布
北沢 遥、石山 華、石川 葵、松林 潤、山田 重人、高桑 徹也

第59回先天異常学会で、発表しました(2019.7.26-28, 名古屋）The 13th World Congress of the International Cleft Lip and Palate Foundation -CLEFT 2019-と合同開催でした。

Nohara A, Owaki N, Manesco C, Katsube M, Yamada S, Imai H, Matsuda T, Yoneyama A, Takakuwa T, Relationship between fusion of lateral palatal shelves and growth of Mandible (Meckel’s cartilage)

Takakuwa　T. Intestinal loop formation: herniation into the extraembryonic coelom and return to the abdominal coelom (招待講演）

Drastic changes occur during the development of the intestinal loop (IL), including physiological umbilical herniation (PUH) and its return. The present study was designed to analyze such developments three-dimensionally during human embryonic and early fetal period.

Materials and Methods: The software AMIRA was used to analyze the 3D digitalized data (high-resolution MRI, phase-contrast X-ray CT) obtained from the Kyoto Collection.

Results and Discussion: Based on the results of our analysis, the following time line and main features of IL formation were revealed:

Herniate phase (Carnegie stage (CS)14-CS23, Crown-rump length (CRL) < 35 mm): IL rotation was initially observed as a slight deviation of the duodenum and colorectum from the median plane up to CS16. The PUH was noticeable after CS16. The IL displayed a hairpin-like structure, with the superior mesenteric artery (SMA) running parallel to the straight part and the cecum located to the left at CS18. The IL rotated around the SMA only during the early stages (until CS19). The IL gradually moved away, running transversely after CS19. Embryos with liver malformation showed PUH, which indicated that PUH occurred independent of liver volume.

Transition phase (CRL = 37, 41, and 43 mm): Intestinal return began from proximal to distal part in samples with CRL of 37 mm. The cecum returned before the distal end of the small intestine (ileum) in samples with CRLs of 41 and 43 mm.

Return phase: The cecum immediately reached its final position in the right lower quadrant of the abdomen (the adult position). The anti-clockwise “en-bloc rotation” described by descent and fixation of the cecum in the abdominal cavity may not exist. A rapid increase in the space available for the intestine in the abdominal coelom that exceeded the intestinal volume in the extraembryonic coelom was observed. The height of the umbilical ring increased in a stepwise manner between the transition and return phases and its height in the return phase was comparable to or higher than that of the hernia tip during the herniation phase. We speculated that the space is generated to accommodate the herniated portion of the intestine, similar to the intestine wrapping into the abdominal coelom as the height of the umbilical ring increases.

Conclusion: The data obtained in the present study demonstrate the precise timeline of IL formations, which indicate several points of discrepancy in the results of previous studies.