Makoto Okamoto

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BACKGROUND Hemorrhage is among the most serious complications of colorectal polypectomy and may occur after a longer postprocedure interval. OBJECTIVE We aimed to elucidate the risk factors for delayed postpolypectomy hemorrhage, including both polyp characteristics and the general condition of the patients. DESIGN Retrospective cohort study. PATIENTS(More)
OBJECTIVES Considering the increasing demand for colonoscopy, auxiliary devices that could facilitate the examination would be useful. A hood attached to the tip of the colonoscope has been reported to be helpful in detecting and removing colorectal polyps. However, its usefulness in aiding scope intubation has not been fully evaluated. METHODS Patients(More)
Epidemiologically, the association between chronic Helicobacter pylori infection and development of gastric cancer is well established. Although the possibility of preventing gastric cancer by eradicating H. pylori infection was recently investigated by several research groups, the results remain controversial. The aim of this study was to determine whether(More)
PURPOSE Colonic diverticulosis, although usually asymptomatic, sometimes causes diverticular hemorrhage. Studies about risk factors, other than nonsteroidal anti-inflammatory drugs, for colonic diverticular hemorrhage are limited. We conducted the present study to elucidate their significance as a risk factor. METHODS Colonic diverticulosis was found in(More)
BACKGROUND Colorectal cancer occurs more frequently in older people. Because the population of aged persons is increasing, a better understanding of the characteristics of colorectal cancer with respect to age would be useful. The purpose of this study was to determine whether there is any relationship between the site of colorectal adenoma and(More)
PURPOSE It is important to identify the definitive molecular switches involved in the malignant transformation of premalignant tissues. Cellular senescence is a specific characteristic of precancerous tissues, but not of cancers, which might reflect tumorigenesis-protecting mechanisms in premalignant lesions. Polycomb protein Bmi1, which is a potent(More)
2000) (9,10). Of the two case-patients, one soldier did not leave NDjamena during his 3-month tour of duty, whereas the other had been in contact with livestock in a flooded area before onset of symptoms. Contamination may have occurred through infected animals or mosquitoes, although sheep living in the area did not show any sign of disease (i.e.,(More)
With the concept of 'human-machine interface', designed especially for visually impaired persons, we have developed an electric aid device for use in guiding orientation and locomotion. The device, which we call CyARM, measures the distance between a person and an object with an ultrasonic sensor and transmits the distance information to the user's haptic(More)
Recent advances in colonoscopic techniques have resulted in more frequent detection of superficial-type colorectal tumors, that is, laterally spreading tumors (LSTs), although little is known about the characteristic clinical features and genetic alterations of LSTs. To elucidate the molecular characteristics of LSTs, genetic alterations in the KRAS, BRAF(More)
The BRAF gene is mutated in 66% of melanomas and less frequently in various human cancers. More than 80% of these mutations are T to A transversions at nucleotide 1796 (T1796A), leading to a substitution of glutamic acid for valine at amino acid 599 (V599E). We established a new method for rapidly detecting V599E mutations using real-time polymerase chain(More)