未利用エネルギー活用技術学習教具の開発-石油給湯器の排熱による発電-

departmental bulletin pape

車椅子エルゴメータの開発

本研究の目的は車椅子駆動時の発揮トルクやパワーを直接測定可能にするための車椅子エルゴメー夕を開発することである。平成9年度は設計の基本コンセプトについて検討し、それに基づいた設計を行ない、試作機を完成させ、実動テストを行なった。平成10年度は完成した試作機の基本性能の検討を行なった。本研究で開発した車椅子エルゴメータは2本のローラーの間に車椅子を乗せ、ローラーに負荷トルクをかけることにより車椅子駆動時の負荷を発生させる仕組みになっている。この場合、通常の路面や床面と比べ、無負荷時の駆動抵抗である残留抵抗(残留負荷)がやや大きくなることが明らかになった。また、この残留抵抗は車椅子に用いられているタイヤの種類やキャンバー角、乗員の体重を含めた車椅子の総重量等によっても異なることが明らかとなった。したがって、生体側から見た駆動時の実負荷はベルトの摩擦によって加えた設定負荷と残留負荷との和となる。そのため、残留負荷を知ることができなければ駆動中のパワーを正しく計算することができない。そこで、本研究では設定負荷0の状態で人が乗車した車椅子をエルゴメータにのせ、駆動用のローラーをモーターで回転させて、その時に必要なトルクを測定することにより残留負荷を計測する装置(トルク検定器)を開発した。また、このトルク検定器を用いることにより、負荷の設定精度の検討も行えるようにした。異なる種類の車椅子に重りを乗せることにより総重量を変化させ、一定速度で駆動用ローラーを回転させたときのトルクを実負荷として実測した。設定負荷と実負荷の関係を検討したところ、両者の間の直線性は高く、残留負荷の測定さえ行なえば十分な精度で駆動パワーの測定が可能であることが明らかとなった。科学研究費補助金 研究種目:基盤研究(B)(2) 課題番号:09558003 研究代表者:池上 康男 研究期間:1997-1998年度research repor

Pleomorphic adenoma of the trachea: A case report

Introduction and importance Although pleomorphic adenoma is the most common type of parotid gland tumor, its occurrence in the trachea is rare. Here, we describe a successfully resected pleomorphic adenoma of the trachea in a woman with severe respiratory failure that had been preoperatively misdiagnosed as asthma. Case presentation A 69-year-old woman presented to the emergency department with symptoms of worsening dyspnea and subsequent loss of consciousness. She had a history of progressively worsening wheezing and stridor over the course of 2-years and had been diagnosed with asthma. Arterial blood gas sample analysis indicated type II respiratory failure. A chest computed tomographic scan revealed a tumor in the trachea, which was almost completely obstructing the lower tracheal lumen. The tumor was located just above the carina. To alleviate airway constriction and achieve complete resection, carinal resection with reconstruction was performed. The postoperative diagnosis was pleomorphic adenoma of the trachea. Clinical discussion Pleomorphic adenoma is a rare tracheal tumor that may present with obstructive airway symptoms that mimic asthma. Conclusion Tracheal tumors should be considered in patients with chronic respiratory symptoms that do not improve with medication

Radiological features and diagnostic pitfalls of idiopathic azygos vein aneurysm: A case report

INTRODUCTION AND IMPORTANCE We present a case of idiopathic azygos vein aneurysm (AVA) and describe its radiological features. Clinicians should be aware of the imaging findings to avoid the risk of bleeding caused by biopsy. CASE PRESENTATION An asymptomatic 46-year-old woman was found to have an abnormal shadow on a chest computed tomography (CT) scan during a medical checkup. Plain CT revealed a well-defined, homogeneous mass on the posterior side of the right main bronchus. Contrast-enhanced CT revealed a mass with marked enhancement pointing to a vascular structure. Three-dimensional reconstruction showed that the mass was connected to the azygos arch, and inflow to and outflow from the azygos vein was detected. Subsequently, video-assisted thoracic surgery was performed. CLINICAL DISCUSSION Patients with idiopathic AVA often present with accidental findings of a mediastinal or lung mass on a chest radiographs or CT scans, which can be mistakenly diagnosed as a paratracheal tumor, bronchial cyst, or posterior mediastinal tumor. Needle biopsy should be avoided due to the risk of massive bleeding. During the evaluation of thoracic malignancies, AVAs should be considered in the differential diagnosis, especially in area of the right tracheobronchial angle or right upper or posterior mediastinum. Three-dimensional reconstruction can help surgeons to clarify the disease diagnosis. CONCLUSION Imaging findings combined with enhanced CT and three-dimensional reconstruction are useful for diagnosing AVAs.Citation: Mayu Inomata, Fumiya Kawano, Ryusei Yamada, Ryo Maeda, Radiological features and diagnostic pitfalls of idiopathic azygos vein aneurysm: A case report, International Journal of Surgery Case Reports, 122, 110094-110094, 2024-09, https://doi.org/10.1016/j.ijscr.2024.11009

Video-assisted thoracoscopic surgery involving a bronchotomy in the removal of a bronchial foreign body: A novel case report

Introduction and importance Bronchial foreign body aspiration is a life-threatening emergency. Largely, the published literature focuses on the removal of foreign bodies by bronchoscopy, while the surgical removal of endobronchial foreign bodies is rarely reported on. Thus, we presented a case of a bronchial foreign body that was successfully removed by a video-assisted thoracoscopic surgical (VATS) bronchotomy, after multiple failed bronchoscopic attempts. Case presentation A 77-year-old male patient presented with a 2-month duration of a persistent cough and low-grade fever after undergoing dental treatment. Bronchoscopy revealed a dental crown surrounded by granulation tissue in the right basal bronchus. The patient was referred to our department for open surgery after undergoing multiple unsuccessful extractions. The bronchial foreign body was removed by a VATS bronchotomy. The postoperative course was uneventful, and the patient was discharged 2 days postoperatively without any complications. Clinical discussion Most aspirated tracheobronchial foreign bodies can be removed through bronchoscopy; nonetheless, certain aspirated foreign bodies may require surgical intervention. Furthermore, the indications for bronchotomies encompass the failure to remove the foreign body despite repeated attempts, due to immobility, with or without distal bronchial placement. Thoracoscopy is beneficial in providing superior visualization, with an increased likelihood of post-bronchotomy recovery. Conclusion VATS bronchotomy is a safe and effective alternative for the removal of bronchial foreign bodies without sacrificing the functioning of the lung parenchyma.Citation: Fumiya Kawano, Mayu Inomata, Ryusei Yamada, Ryo Maeda, Video-assisted thoracoscopic surgery involving a bronchotomy in the removal of a bronchial foreign body: A novel case report, International Journal of Surgery Case Reports, 121, 110018-110018, 2024-08, https://doi.org/10.1016/j.ijscr.2024.11001

Radiological features of intrathoracic chronic expanding hematoma: A case report

Introduction and importance We present a relatively rare case of intrathoracic chronic expanding hematoma (CEH) after thoracic surgery for lung cancer. CEH is often difficult to distinguish from malignant tumors because of its large size and slow progressive enlargement. In this report, we describe the radiological features of CEH in detail. Case presentation A 67-year-old man who underwent a left upper lobectomy for lung cancer at 46 years of age presented with hemosputum. Computed tomography revealed a large mass with central low attenuation. Calcification was detected in peripheral lesions of the mass. T2-weighted magnetic resonance imaging (MRI) revealed a mass with mixed low and high signal intensities. Based on the clinical course, the patient was diagnosed with an intrathoracic CEH. A left posterolateral thoracotomy was performed with the patient in the lateral position, and a mass encased in a tough capsule was resected. The postoperative histopathological findings were consistent with CEH. Clinical discussion CT of intrathoracic CEH shows a lesion with heterogeneous content, a thick wall, and calcifications. However, differentiation from malignant tumors is difficult using CT alone. MRI is a good diagnostic modality for CEH and often shows a mixture of low- and high-intensity areas on T2-weighted images. In addition, the patient's medical history is important because most cases of CEH have a history of trauma or surgery. Conclusion To diagnose intrathoracic CEH, it is essential to consider the patient's clinical course and MRI findings.Citation: Inomata M, Kuroki S, Nakada H, Kawano F, Maeda R. Radiological features of intrathoracic chronic expanding hematoma: A case report. Int J Surg Case Rep. 2023 Sep;110:108767. doi: 10.1016/j.ijscr.2023.108767. Epub 2023 Aug 29. PMID: 37683511; PMCID: PMC10510069

Primary pulmonary colloid adenocarcinoma: A case report of a rare subtype

Introduction and importance Pulmonary colloid adenocarcinoma is an extremely rare subtype of lung adenocarcinoma. Owing to its rarity, the detailed clinical features of colloid adenocarcinoma remain largely unknown. This report describes a case of early-stage colloid adenocarcinoma that recurred soon after resection, including its radiological findings. Case presentation During a routine checkup, a chest roentgenogram revealed an abnormal shadow in the right upper lung field of an asymptomatic 68-year-old man. Computed tomography (CT) showed a well-defined, low-attenuation nodule in the right upper lobe. Right upper lobectomy with mediastinal lymph node dissection was performed. The postoperative histopathological diagnosis indicated pulmonary colloid adenocarcinoma. The pathological stage was classified as T1bN0M0 (stage IA2). Follow-up CT 1 year after the resection revealed an enlarged supraclavicular lymph node and pulmonary nodule in the right lower lobe. Both lesions appeared as well-defined solitary hypoattenuated tumors with minimal enhancement on CT images. Excisional biopsies of both tumors were performed to obtain a definitive diagnosis. Both tumors consisted of abundant mucin in which some tumor cells were floating and were diagnosed as colloid adenocarcinoma recurrences. Clinical discussion Although colloid adenocarcinoma is generally considered to have indolent clinical behavior, it can recur even in early-stage cases. Conclusion Colloid adenocarcinoma is a distinct variant of lung adenocarcinoma, characterized by well-circumscribed mucinous lesions with alveolar wall destruction caused by mucin pools and scant tumor cells. The treatment strategy for colloid adenocarcinoma should follow the guidelines for primary lung cancer.Citation: Ryusei Yamada, Nobuyuki Oguri, Fumiya Kawano, Mayu Inomata, Yuichiro Sato, Ryo Maeda, Primary pulmonary colloid adenocarcinoma: A case report of a rare subtype, International Journal of Surgery Case Reports, 123, 110260-110260, 2024-10, https://doi.org/10.1016/j.ijscr.2024.11026

Relationship of immunonutritional factor with changes in liver volume after portal vein embolization

application/pdfBackground To identify predictors of changes in hepatic volumes after portal vein embolization, we examined the relationship with preoperative nutritional and immunological parameters. Patients and Methods Ninety-three patients who underwent portal vein embolization were included. The control group comprised 13 patients who underwent right hepatectomy without portal vein embolization. Computed tomographic volumetric parameter was measured for changes in embolized and nonembolized liver. Correlation with various candidates of immunonutritional parameters was examined. Results Difference in increased liver ratio was 9.1%. C-reactive protein levels significantly increased after portal vein embolization （P  0.92 and increased liver volume ≥ 10% tended to correlate with lower prevalence of severe complications. Only increased intraoperative blood loss ≥ 1,500 mL was significantly associated with morbidity and mortality （P < .05）. Conclusion Contrary to our hypothesis, immunonutritional parameters, except C-reactive protein and C-reactive protein/albumin ratio, did not reflect hypertrophy after portal vein embolization. Although it is difficult to predict the hypertrophic degree, the strategy of scheduled hepatectomy should be switched in case of impaired inflammatory status after portal vein embolization

Observation of the ηc(2S) in Exclusive B→KKSK-π+ Decays

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Feedback Provision in L2 Writing Classes: The Use of Poster Presentations to Fill a Gap

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