Research projects

The Nuss procedure, which corrects the chest wall using a titanium bar, is commonly utilized for surgical treatment of pectus excavatum. The varied form of pectus excavatum among patients underscores the importance of understanding its characteristics for effective surgical intervention. Factors such as the degree and asymmetry of the depression, as well as bone sclerosis associated with age, contribute to the complexity of pectus excavatum surgery. Through objective analysis of pectus excavatum morphology via image analysis, we have identified challenges with the Nuss procedure. As a result, we have developed a new surgical approach, the Combined Ravitch and Nuss Procedure (CRN procedure), which integrates the Nuss and Ravitch procedures as an innovative treatment method ready for clinical practice.

Malignant pleural mesothelioma is widely resistant to therapies, and new treatment starategies are needed. We clarified that zoledronic acid reduces cell viavility and cell migration of human malignant pleural mesothelioma cells in vitro, and that induction of autophagic changes may at least in part be involved in this process.

Malignant pleural mesothelioma is widely resistant to therapies, and new treatment starategies are needed. Recent reports have indicated the potential efficacy of statins against malignant pleural mesothelioma cells in vitro. Here we show that lovastatin reduces primary tumor and metastasis in a mouse model of human malignant pleural mesothelioma, and that induction of autophagic changes may at least in part be involved in this process.

肺悪性腫瘍に冷却ガスが通じる専用の凍結端子(プローブ)を刺入して凍結させる凍結融解壊死療法があり、現在、CTガイド下に経皮的に施行し良好な局所制御率を得ている。しかしながら胸壁と胸膜を貫いてプローブを刺入するため、血気胸、播種、空気塞栓などの危険性がある。本研究グループは凍結療法を気管支鏡を用い経気管支的に行うことで合併症が回避でき、より低侵襲となることを初めて提唱した。複数の病変に繰り返し治療でき多発病変の治療にも適している。本研究では肺悪性腫瘍に対する気管支鏡を用いた経気管支的凍結融解壊死療法の有効性と安全性を動物モデルで検証すると共に、気管支鏡専用凍結プローブの開発と手技の確立を行う。

ヒト肺癌細胞株・悪性胸膜中皮腫細胞株に対して、in vitroで一酸化窒素ドナーDETA-NOがアポトーシスを誘導することを確認した。その効果は低酸素(1%)環境下で増強した。ヒト肺癌細胞株・悪性胸膜中皮腫細胞株のマウス胸腔移植モデルを作成した。特に悪性胸膜中皮腫のリンパ節転移モデルはこれまでに報告がない貴重なモデルである。

Cross-linked poly (gamma-glutamic acid) (PGAXL) is a biodegradable polymer capable of forming a hydrogel. In the present study, using a mouse model of thoracotomy, we investigated whether local application of PGAXL could attenuate adhesion formation at the thoracotomy site. We found that local application of PGAXL attenuated adhesion formation at the site of thoracotomy between the lung and the parietal pleura as well as between the chest wall and the chest muscles..

As pericardial effusion separates pericardium and cardiac muscle, cardiac muscle itself seems not to be frozen. However, when treated area of the lung is nearly located to coronary artery, it is afraid that the low temperature might induce the constriction of coronary artery. Therefore, we performed an examination with porcine. Under the general anesthesia, coronary artery's blood flow was measured by electric blood flow meter. The temperature of coronary's surrounding tissue was decreased gradually near to 0℃ by cryoablation. Flow meter showed no decrease of coronary flow under this condition. Next, cryo-probe touched coronary artery directly. Cryoablation could make coronary artery and vein frozen. After thawing, flow meter indicated that the coronary flow was recovered up to the previous level. Cardiac muscle near-by coronary artery was also frozen and after sacrifice of porcine pathological examination showed death of outer half cardiac muscle due to cryoablation. However, during examination, cardiac output, heart rate, and blood pressure were preserved.

肺は大量の空気を含む臓器であるため凍結端子を中心とする凍結領域の時間的空間的拡がりについてこれまでまったく基礎データが得られていなかった。そこで全身麻酔科の豚肺を用いて凍結端子を中心に同心円状に4, 6, 8, 10mmの距離に熱電対を刺入して経時的な温度変化を追跡し、正常肺における凍結時間と凍結距離、温度の関係および融解に要する時間と融解範囲の関係を明らかにした。今後は凍結中に凍結範囲を3次元的に描出する装置の工夫が必要であり、現在作成中である。

With thermal monitoring of porcine lung treated by cryoablation, sequential spread of low temperature zone around cryoprobe in the porcine lung could be imaged theoretically. Then correlation between CT findings and pathological feature after lung cryoablation and low temperature zone(less than-20℃) during cryoablation was evaluated. These data should make possible to construct computed simulation system for optimal insertion of cryoprobe in the lung.