Biomedical subjects

Masaharu Nagayama

Publications and source records attributed to Masaharu Nagayama.

5 recordsLinked to original sources

PubMed2006

[Two cases of acute respiratory failure due to idiopathic interstitial pneumonia successfully treated with sivelestat sodium hydrate and steroid therapy].

We encountered two patients with clinically diagnosed idiopathic interstitial pneumonia with acute respiratory distress syndrome (ARDS). Both patients required mechanical ventilation within 24 hours after admission. We managed these patients using lower tidal volume ventilation (tidal volume: 5-6 ml/kg), antibiotics, sivelestat sodium hydrate and steroid pulse therapy followed by oral prednisolone therapy. Respiratory failure was relieved within 2 weeks following treatment There was no four-fold rise in screen viral titers and screening investigations of autoantibodies were negative. Based on these findings, we diagnosed these cases as having acute interstitial pneumonia (AIP). AIP represents a small subset of patients with ARDS without any associated or predisposing factor. Sivelestat sodium hydrate is an anti-neutrophil elastase inhibitor and is used for the treatment of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Therefore, sivelestat sodium hydrate may be one of the treatment options for acute respiratory failure due to idiopathic interstitial pneumonia.

Acute Disease↗

PubMed2005

Chemosensitive running droplet.

Chemical control of the spontaneous motion of a reactive oil droplet moving on a glass substrate under an aqueous phase is reported. Experimental results show that the self-motion of an oil droplet is confined on an acid-treated glass surface. The transient behavior of oil-droplet motion is also observed with a high-speed video camera. A mathematical model that incorporates the effect of the glass surface charge is built based on the experimental observation of oil-droplet motion. A numerical simulation of this mathematical model reproduced the essential features concerning confinement of oil droplet motion within a certain chemical territory and also its transient behavior. Our results may shed light on physical aspects of reactive spreading and a chemotaxis in living things.

Journal Article↗

PubMed2005

[Placement of an ultraflex nitinol stent for severe tracheobronchial obstruction in a case of relapsing polychondritis].

A 59-year-old man, who had been treated for bronchial asthma since 2000, was hospitalized with high fever and productive cough in November 2003. Chest radiography on admission showed consolidations in both lower lung fields, and computed tomography demonstrated anteroposterior narrowing of both main bronchi. A physical examination revealed deformity of auricular cartilage and saddle nose, and we diagnosed him relapsing polychondritis (RP). When he was readmitted 4 months later because of severe tracheobronchial stenosis and respiratory failure he required mechanical ventilation, but it was difficult to wean him from the ventilator. Self-expandable metallic stents were placed in the left main bronchus and the trachea. After the procedure, he was successfully weared from mechanical ventilation. Since airway complications of RP can be fatal, stent implantation should be considered in the management of RP with airway manifestations.

Alloys↗

PubMed2002

[Follicular bronchiolitis preceding rheumatoid arthritis].

A 52-year-old woman visited our hospital because of a cough and stridor in 1994. She had a history of non-tuberculous mycobacteriosis and chronic paranasal sinusitis. Her chest CT scan showed scattered centrilobular nodular shadows and peribronchial thickening, and so we suspected recurrent non-tuberculous mycobacteriosis or diffuse panbronchiolitis. Clarithromycin treatment was initiated, but she soon ceased taking the drug. She visited our hospital again because of a severe cough three and half years later. A new chest CT scan showed increased abnormal shadows, and so we suspected worsening non-tuberculous mycobacteriosis or diffuse panbronchiolitis. Consequently, we commenced treatment with rifampicin, ethambutol hydrochloride as well as clarithromycin. One year later, rheumatoid arthritis was diagnosed because of a swollen proximal interphalangeal joint in both fourth fingers. Her respiratory symptoms were not relieved with clarithromycin or antituberculous drugs, so a thoracoscopic biopsy was performed for a more accurate diagnosis. Histological examination revealed follicular bronchiolitis.

Arthritis, Rheumatoid↗

PubMed1997

Nonannihilation dynamics in an exothermic reaction-diffusion system with mono-stable excitability.

We consider a 2-component excitable and diffusive system which describes a simple exothermic reaction process. In some parameter regime, there are two characteristics of travelling pulses of the system: (i) travelling pulses are planarly unstable; (ii) when two travelling pulses approach closely, they do not annihilate each other and repel like elastic objects. Under this situation, it is shown that ring patterns break down into complex patterns in 2-dimensions, which are totally different from those arising in the well-known excitable and diffusive system with the FitzHugh-Nagumo nonlinearity. (c) 1997 American Institute of Physics.

Journal Article↗