A Novel Approach for Investigating Upper Airway Hyperresponsiveness Using Micro-CT in Eosinophilic Upper Airway Inflammation such as Allergic Rhinitis Model.

Airway hyperresponsiveness (AHR) has been proposed as a feature of pathogenesis of eosinophilic upper airway inflammation such as allergic rhinitis (AR). The measurement system for upper AHR (UAHR) in rodents is poorly developed, although measurements of nasal resistance have been reported. Here we assessed UAHR by direct measurement of swelling of the nasal mucosa induced by intranasal methacholine (MCh) using micro-computed tomography (micro-CT). Micro-CT analysis was performed in both naïve and ovalbumin-induced AR mice following intranasal administration of MCh. The nasal cavity was segmented into two-dimensional horizontal and axial planes, and the data for nasal mucosa were acquired for the region of interest threshold. Then, a ratio between the nasal mucosa area and nasal cavity area was calculated as nasal mucosa index. Using our novel method, nasal cavity structure was clearly identified on micro-CT, and dose-dependent increased swelling of the nasal mucosa was observed upon MCh treatment. Moreover, the nasal mucosa index was significantly increased in AR mice compared to controls following MCh treatment, while ovalbumin administration did not affect swelling of the nasal mucosa in either group. This UAHR following MCh treatment was completely reversed by pretreatment with glucocorticoids. This novel approach using micro-CT for investigating UAHR reflects a precise assessment system for swelling of the nasal mucosa following MCh treatment; it not only sheds light on the mechanism of AR but also contributes to the development of new therapeutic drugs in AR patients.

Penetrating Aortic Root Injury / 日本心臓血管外科学会雑誌

The patient was a 25-year-old man, who had been stabbed with a weapon siarilar to long ice pick. Thirty minutes later, he was admitted to our emergency center by ambulance. Anchocardiogram on admission revealed moderate pericardial effusion with normal heart function. Contrast medium enhanced computed tomography revealed that the weapon had entered from the left anterolateral chest wall and reached the posterior wall of the aortic root, approximately 1 cm above the left coronary artery orifice, through the left lung. During examinations, he suddenly went into shock and emergency open pericardial drainage was performed immediately. Approximately 400 ml of blood with a clot was removed from the pericardial cavity. After this procedure, there was no continuous bleeding. Subsequently, pseudoaneurysm developed at the aortic root injury site. Twenty seven days later, aortic surgery was performed. The injury site was resected and sutured directly, employing 4-0 polypropylene sutures with felt pledgets. He was discharged 14 days after the operation without any complications.