ミトコンドリア障害細胞における酸化ストレス感受性と細胞膜動態

Oxidative stress is a harmful state for the cell. The state arises from exposure to high levels of reactive oxygen species（ROS）．ROS is a key molecule in maintaining cell proliferation, inflammation and cell death. ROS is also involved in aging and causes many diseases such as Parkinson s disease, Alzheimer s disease, cancer, diabetes mellitus and periodontal disease. The primary site of ROS generation in vivo is mitochondria. Mitochondria have its own DNA（mtDNA）that encodes a part of oxidative phosphorylation component proteins in mitochondria, and mtDNA damage by ROS causes neurodegenerative diseases and various types of cancer. Therefore, these damaged cells will provide valuable cell models to study oxidative stress and overcome ROS derived diseases. To analyze the mechanism of oxidative stress and ROS derived diseases, mtDNA depleted cells（ρ0 cells）are developed by treating low dose ethidium bromide. ρ0 cells do not have mtDNA, can\u27t survive without pyruvate and uridine, produce little amount of ATP, sensitive to oxidative stress and generate higher ROS compared with parental cell. in this review, we describe the cellular response by oxidative stress such as radiation and hydrogen peroxide using ρ0 cells. we also discuss the relationship among oxidative stress sensitivity, mitochondria damage and plasma membrane status

心房中隔ペーシングにより発作性心房細動が抑制された慢性透析患者の1例

Article長野県透析研究会誌 30(1): 33-35(2007)journal articl

Comparative Study of Image Performance for Digitized Image Archiving No.2 : Image evaluation on dental radiographs and CRT imaging in apical periodontitis

Electronic image-reading and storing of radiographs obtained in the field of stomatology is a goal in dental radiology. Using a popular-type image scanner with an 8-bit intensity level, original dental radiographs and images on a CRT monitor have been compared and evaluated visually. To make this evaluating method more concrete, the optimal conditions for image scanning were obtained, then, using actual images on apical periodontitis and the receiver operating characteristics (ROC) analysis, more objective evaluation of the original radiographs and CRT images was attempted. The dental radiographs were converted to electronic signals, and images on CRT were evaluated by the ROC analysis. The evaluations were similar to those obtained with the dental radiographs. In the examination of apical periodontitis, image-reading and diagnosis on CRT is feasible. It appears to be important for the observer to have sufficient priorunderstanding of the characteristics of the scanner and that the radiographic imaging be performed with an adequate X-ray dose