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H Murao

Publications and source records attributed to H Murao.

16 recordsLinked to original sources

Colonic muco-submucosal elongated polyp: diagnosis with endoscopic ultrasound.

Colonic muco-submucosal elongated polyp is a new clinical entity first reported in 1998. The purpose of this report is to determine the value of endoscopic ultrasound in the diagnosis of this condition. We reviewed the endosonographic and histological findings of seven colonic muco-submucosal elongated polyps that were removed completely by endoscopic resection or surgery. The lesions appeared as pedunculated submucosal tumours, measuring 1-4 cm in maximal diameter. Endosonographically, all lesions consisted of mucosal and submucosal layers, and microcystic components were found in the submucosal layer. There were no echogenic masses or muscularis propria within the polyps. These endosonographic features corresponded to histological findings of this type of polyp which was covered with normal mucosa and composed of submucosal layer alone. The submucosal layer consisted of oedematous, loose, connective tissue and/or fibrous tissue, accompanied by dilated blood vessels and lymphatics. Endoscopic ultrasound enabled differentiation of colonic muco-submucosal elongated polyp from other submucosal lesions.

Adult↗

High incidence of silent myocardial ischemia in elderly patients with non insulin-dependent diabetes mellitus.

The present study was designed to reveal the incidence of silent myocardial ischemia in asymptomatic elderly non-insulin-dependent diabetic (NIDDM) patients (aged over 60 years). As a first step screening, maximal treadmill exercise test was performed. Of 140 patients studied, 54 (38.6%) were unable or not expected to achieve diagnostic levels of exercise during treadmill testing. A positive exercise test was noted in 39 of 86 (45.3%) subjects. As a second step examination, dipyridamole thallium scintigraphy was performed for 93 subjects who exhibited a positive exercise test and could not perform a maximal exercise test. Abnormal perfusion pattern was found in 39 of 93 (41.9%), who were finally considered to have a silent myocardial ischemia. Coronary angiography was performed in 18 subjects with diagnosis of silent myocardial ischemia, who gave their consent. Significant coronary artery stenosis was in fact found in 17 of 18 (94.4%) subjects studied, confirming a very high positive predictive value of this diagnostic procedure. In conclusion, elderly NIDDM patients (aged over 60 years) had an extremely high prevalence (estimated 26.3%) of silent myocardial ischemia. This evidence suggests that early and intensive detection may be needed as a part of routine care for this group.

Aged↗

Sodium fluoride increases intracellular calcium in rat renal epithelial cell line NRK-52E.

In our previous experiment using rats, fluoride was reported to cause renal calcification, whose mechanism was deduced to be due to an increase in parathyroid hormone (PTH) secretion. However fluoride-induced renal calcification that was independent of PTH has not been understood well in the nephron of fluoride-treated animals. Thus, we examined the effect of sodium fluoride on intracellular calcium mobilization in a normal rat kidney epithelial cell line (NRK-52E cells). The calcium accumulation was found to be remarkably increased by the addition of sodium fluoride (NaF). The elevation of [Ca2+]i was demonstrated to be due to calcium entry through nifedipine-sensitive calcium channels. In addition, fluoride activates phospholipase C, but inositol 1,4,5-triphosphate (IP3) didn't induce Ca2+ release from the endoplasmic reticulum (ER). Moreover, fluoride alone was deduced to enhance the activity of ER-type Ca2+-ATPase. Finally, on the mechanism of fluoride-induced calcium accumulation in NRK-52E cells, fluoride may activate phospholipase C to generate IP3 and diacylglycerol, and these increases can be elucidated to induce calcium entry through dihydropiridine-sensitive calcium channels. Moreover, fluoride was found to stimulate calcium accumulation through ER-type Ca2+-ATPase into the endoplasmic reticulum. The elevation of ER-type Ca2+-ATPase activity by fluoride was elucidated to operate as a regulatory system to protect against abnormally higher increases in cytosolic calcium concentration via an increase of calcium influx into the endoplasmic reticulum.

Animals↗

Magnetic resonance imaging of anterior cruciate ligament (ACL) tears: diagnostic value of ACL-tibial plateau angle.

Tears of the anterior cruciate ligament (ACL) are often difficult to diagnose on magnetic resonance imaging (MRI), as it is often difficult to interpret the images. We developed a quantitative method for diagnosing ACL tears on MRI; the method involves measuring the angle formed by the intersection between a straight line drawn along the anterior border of the ACL and a straight line drawn along the medial tibial plateau (AT angle) on MRI. The AT angle was measured by two orthopedic surgeons approved by the Japanese Orthopedic Association and one orthopedic resident, none of whom had any prior knowledge of the physical and arthroscopic findings of the patients. Measurements were performed in 30 knees with ACL tears and 57 knees without tears. There was no significant difference between the AT angles measured by the three examiners in either the group with ACL tears or that without ACL tears. The mean value of the AT angle in the torn ACL group (33.9 +/- 1.1 degrees) was significantly smaller than that in the intact ACL group (52.3 +/- 1.0 degrees; mean +/- SE). When 45 degrees or less was set as the criterion defining a tear of the ACL, the diagnostic accuracy of our method was 87.4%; sensitivity was 93.3%, and specificity, 84.2%.

Adolescent↗

[Outcome of long-term nasal intermittent positive pressure ventilation in 41 patients with hypercapnic respiratory failure].

Nasal intermittent positive pressure ventilation (NIPPV) is widely used in domiciliary treatment of chronic ventilatory disorders. The outcomes of long-term NIPPV were analyzed in 41 patients with hypercapnic respiratory failure due to pulmonary tuberculosis sequelae (PTS; n = 17), neuromuscular disease (NMD; n = 8), kyphoscoliosis (KS; n = 7), chronic obstructive pulmonary disease (COPD; n = 6), and miscellaneous diseases (n = 3). Twenty-seven patients with chronic conditions but without acute exacerbations began receiving NIPPV, and fourteen patients began receiving NIPPV after an acute exacerbation. Outcome measures included the probability of continuing NIPPV, survival after starting NIPPV, survival after starting home oxygen therapy (HOT), arterial blood gases, nocturnal oxygen saturation, pulmonary function, and the number of hospital days. Two patients with PTS died, 7 and 40 months after starting NIPPV. Two patients (one with PTS and one with COPD) switched from NIPPV to intermittent positive pressure ventilation via a tracheostomy. The condition of one patient with NMD improved and NIPPV was discontinued. The three-year and five-year probabilities of continuing NIPPV in all patients were 82%, and 71%, respectively. The survival rates three and five years after starting NIPPV were 97% and 85%, respectively. The survival rates one to nine years, and ten to eleven years after starting HOT were 98% and 65%, respectively. The arterial PO2 and PCO2, nocturnal oxygen saturation, vital capacity, and forced expiratory volume, in one second all improved after NIPPV was begun. NIPPV also reduced the number of hospital days, particularly in patients with KS. In conclusion, the long-term outcome of NIPPV in patients with hypercapnic respiratory failure is encouraging.

Adult↗

Ventilatory effects on pulmonary vascular inflow and outflow patterns.

Ventilation of an isolated lung lobe modifies the rate of inflow into its pulmonary artery (Murao and Rodbard, 1971). The present studies show that ventilation also influences the rate of outflow from the pulmonary vein in a manner which differs significantly from the effects on the rate of inflow into the pulmonary artery. Since this difference between instantaneous inflow and outflow rates affects the calculation of vascular conductance (resistance) and its interpretation we have compared and analysed the effects of ventilation on simultaneous flow patterns in the pulmonary artery and vein.

Acetylcholine↗