Rare complications of hyperbaric oxygen therapy

Hyperbaric oxygen therapy (HBOT) for carbon monoxide (CO) poisoning is widely performed to prevent delayed neuropsychiatric syndrome. Although HBOT can generally be performed with safety, the appropriate management of HBOT still remains unestablished. A 31-year-old man was transferred to our facility to undergo HBOT in a multiplace chamber with a diagnosis of CO poisoning. The first HBOT session ended uneventfully. During the second HBOT session, the patient suddenly experienced convulsive seizures. The accompanying doctor administered intravenous propofol to stop the convulsion and terminated the HBOT. Soon after the convulsion, the patient developed frothy secretions through the endotracheal-tube with impaired oxygenation. Head computed tomography scan showed no abnormalities, suggesting the seizure was associated with complications of HBOT. A chest X-ray revealed bilateral pulmonary edema, and echocardiography revealed normal cardiac function, indicating that the pulmonary edema resulted from HBOT or neurogenic mechanism secondary to the seizure. The patient’s respiratory status improved without recurrence of the seizure and no delayed neurological sequelae was seen afterwards. Here we report unexpected rare adverse events during HBOT. Hyperbaric oxygen therapy for acute indications should be performed in multiplace chambers, with appropriate preparation and medical equipment

The renin–angiotensin system promotes arrhythmogenic substrates and lethal arrhythmias in mice with non-ischaemic cardiomyopathy

[Aims]The progression of pathological left ventricular remodelling leads to cardiac dysfunction and contributes to the occurrence of malignant arrhythmias and sudden cardiac death. The underlying molecular mechanisms remain unclear, however. Our aim was to examine the role of the renin–angiotensin system (RAS) in the mechanism underlying arrhythmogenic cardiac remodelling using a transgenic mouse expressing a cardiac-specific dominant-negative form of neuron-restrictive silencer factor (dnNRSF-Tg). This mouse model exhibits progressive cardiac dysfunction leading to lethal arrhythmias. [Methods and results]Subcutaneous administration of aliskiren, a direct renin inhibitor, significantly suppressed the progression of pathological cardiac remodelling and improved survival among dnNRSF-Tg mice while reducing arrhythmogenicity. Genetic deletion of the angiotensin type 1a receptor (AT1aR) similarly suppressed cardiac remodelling and sudden death. In optical mapping analyses, spontaneous ventricular tachycardia (VT) and fibrillation (VF) initiated by breakthrough-type excitations originating from focal activation sites and maintained by functional re-entry were observed in dnNRSF-Tg hearts. Under constant pacing, dnNRSF-Tg hearts exhibited markedly slowed conduction velocity, which likely contributes to the arrhythmogenic substrate. Aliskiren treatment increased conduction velocity and reduced the incidence of sustained VT. These effects were associated with suppression of cardiac fibrosis and restoration of connexin 43 expression in dnNRSF-Tg ventricles. [Conclusion]Renin inhibition or genetic deletion of AT1aR suppresses pathological cardiac remodelling that leads to the generation of substrates maintaining VT/VF and reduces the occurrence of sudden death in dnNRSF-Tg mice. These findings demonstrate the significant contribution of RAS activation to the progression of arrhythmogenic substrates

MRTF-Aとmyocardinの相反的発現変化のマウス病的血管リモデリングにおける重要性

京都大学0048新制・課程博士博士(医学)甲第17413号医博第3756号新制||医||996(附属図書館)30179京都大学大学院医学研究科医学専攻(主査)教授 山下 潤, 教授 瀬原 淳子, 教授 木村 剛学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDA

A method of ion temperature determination with retar ding potential analyzer by computer

We have been measuring the ion temperature by means of a retarding potential analyzer (RPA) aboard the sounding rocket whose velocity is comparable to the ion thermal velocity. In order to determine the ion temperature T_i from the RPA data, an optimum fitting procedure is used. It was believed that the deduction of T_i at low ram velocity by computer methods without assumption of ion mass number was impossible. This paper deals with an improved accurate fitting procedure to obtain T_i and mixed ion mass number. We advocate the usefulness of the improved error evaluation function. We also show the actual data analysis procedure

Differential Resonance Probe (Electron Density Probe)

This paper deals with "differential resonance probe method", which is one of the RF plasma probe techniques. This probe method is compared with other electron density probe method

Meaning of the vertical profile of ion temperature over the Antarctic

The existence of horizontal stratifications of ion temperature has been reported by several workers. In the mid-latitude region we too observed such a wavelike temperature variation using a sounding rocket. These phenomena may be caused by atmospheric oscillations. The observations are thought to be important over the polar region. In this paper we propose an explanation for the observation of the vertical profile of the ion temperature over the Antarctic

サドウ レゾナンスプローブ デンシ ミツド ソクテイ

This paper deals with "differential resonance probe method", which is one of the RF plasma probe techniques. This probe method is compared with other electron density probe method