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Y Minamiya

Publications and source records attributed to Y Minamiya.

29 records · Page 2Linked to original sources
PubMed1996

Ca2+ waves in lung capillary endothelium.

Although cytosolic Ca2+ importantly regulates organ function, lung microvascular [Ca2+]i regulation remains poorly understood because of the lack of direct in situ quantification. In the present study, we report the first endothelial [Ca2+]i quantification by the fura 2 method in microscopically imaged venular capillaries of the isolated blood-perfused rat lung. Sequential images indicated the presence of intercellular Ca2+ waves that spontaneously originated from pacemaker endothelial cells and then spread for short distances along the capillary wall, inducing synchronous endothelial [Ca2+]i oscillations. Fast Fourier analyses of the oscillations revealed a dominant wave component with an amplitude of 37 nmol/L, frequency of 0.4 min-1, and velocity of 5 microns/s. The intracellular Ca2+ wave was unaffected by blood flow stoppage or by infusions of Ca(2+)-containing or Ca(2+)-free dextran. Inhibition of the wave by thapsigargin in Ca(2+)-free dextran and by the gap junction uncoupler, heptanol, indicated that it was generated by endosomal Ca2+ release in the pacemaker cell and was propagated by gap junctional communication. In the presence of histamine, enhancement of the wave accounted for a significant component of the coordinated [Ca2+]i increase in the capillary segment. No intercellular Ca2+ waves were evident in adjoining alveolar epithelial cells. Our findings indicate a novel mechanism of [Ca2+]i regulation in the lung capillary under both resting and stimulated conditions. Pacemaker-induced Ca2+ waves, generated intracellularly by unknown initiating mechanisms, communicated to adjoining cells to determine [Ca2+]i profiles in short interbranch segments of capillary walls.

Animals↗
PubMed1996

[Analysis of specificity of resected esophageal cancer patients with a history of apoplexy].

We studied 15 resected cases with a history of apoplexy (2.5%) among 599 cases of esophageal cancer admitted between 1972 and 1993. Fourteen were male, and female, aged 48 to 77 years. Twelve had suffered from cerebral infarction, 2 intracerebral hemorrhage, and one subarachnoid hemorrhage. Duration from apoplexy to operation was between 2 months and 19 years in the cerebral infarction cases, between 8 and 10 years in the intracerebral hemorrhage cases and 4 years in the subarachnoid hemorrhage case. Preoperative neurological disturbance was found in 7 of the 12 cerebral infarction cases, and in both intracerebral hemorrhage cases. Four cases showed hemiplegia, and the other 5 cases showed partial paralysis of limbs. Preoperative complications were found in 7 of the 15 cases, and consisted of diabetes mellitus in 5, hypertension in 4, bronchial asthma in one, and renal dysfunction in one case. Intra- and postoperative complications were found in 11 of the 15 cases, and consisted of anastomotic leakage in 5, delirium in 3, apoplexy in 2, peritonitis in one, ARDS in one, intraoperative cardiac arrest in one, and wound infection in one. Postoperative disorders of consciousness were found in 5 cases, consisting of delirium in 3, and excitation at awakening of anethesia in 2 cases. Rate of direct operative death was 6.7% in preoperative apoplectic patients, and 8.5% in non-apoplectic patients, and there was no significant difference between the 2 groups. On the other hand, rate of postoperative apoplexy was 13.3% in the preoperative apoplectic patients, and 0.4% in non-apoplectic patients. There was a significant difference between them (p < 0.01). But they were cured of it, and left our hospital. It is concluded that active surgical treatment can be indicated for esophageal cancer patients with a history of apoplexy, if more attention is given to the management of diabetes mellitus or hypertension.

Aged↗
PubMed1995

Endotoxin-induced hydrogen peroxide production in intact pulmonary circulation of rat.

Although the importance of free oxygen radical has been reported in acute lung injury, the direct evidence in vivo model was lacking. We report a new method, which for the first time allows direct detection of hydrogen peroxide in the intact rat pulmonary microcirculation. We used the computer image-analyzing system and 2',7'-dichlorofluorescin diacetate for the marker of hydrogen peroxide production in vivo. A rat sepsis model was produced by continuous infusion of endotoxin for 30, 60, and 120 min. Hydrogen peroxide production in the pulmonary microcirculation of the sepsis rat was higher than in the control rat at each time point (p < 0.01) and increased time-dependently (p < 0.01). Catalase (5,000 U/kg) almost completely inhibited the hydrogen peroxide production in the sepsis rat (p < 0.01). In high-power view, hydrogen peroxide was detected in granulocytes that adhered to the capillaries and endothelial cells that were adjoining adherent granulocytes. These observations suggest that hydrogen peroxide in the endothelium was diffused from granulocytes. In this study, we demonstrated direct evidence of hydrogen peroxide production from adherent granulocytes in intact rat lung treated with endotoxin. We conclude that endotoxin causes the granulocyte adhesion and oxidative stress to the endothelium due to adherent granulocytes within 30 min in the pulmonary microcirculation.

Animals↗
PubMed1995

[Retrospective study of sputum culture after esophagectomy].

We retrospectively investigated the sputum cultures of patients who underwent esophagectomy (n = 104) from just after operation to 11 postoperative days and evaluated the factors which influenced the cultures. We divided the 0-11 postoperative days into three periods (0-3 postoperative days (p.o.d.), 4-7 p.o.d., 8-11 p.o.d.). The sputum cultures were positive at a rate of 56.7% to 65.4% of patients during the period of observation (0-11 p.o.d.). Gram-negative bacillus was mostly detected. MRSA increased time-dependently. Diabetes mellitus, preoperative irradiation recurrent nerve palsy did not influence the positive rate of the sputum cultures. The positive rate of gram-negative bacillus and gram gram-positive coccus in the sputum of the patients who were given sefem-first generation antibiotics was lower than of patients who were given sefem-second generation antibiotics at 8-11 p.o.d. (p < 0.05). The positive rate of gram-negative bacillus in the sputum of patients who underwent esophagectomy with laryngectomy for cervical esophageal cancer was lower than that of patients who underwent esophagectomy without laryngectomy for thoracic or abdominal esophageal cancer at 4-7 p.o.d. (p < 0.05). The positive rate of gram-negative bacillus in the sputum of patients who underwent intraoperative tracheostomy was lower than that of patients who did not undergo intraoperative tracheostomy at 4-11 p.o.d. No patients had pneumonia during the period of observation except for the secondary lung complications. In conclusion, although we have done a good job of management, we should select the appropriate antibiotics with the patient's background in mind.

Aged↗
PubMed1993

[A resected case of well-differentiated adenocarcinoma simulating fetal lung tubules which is a variant of pulmonary blastoma].

A case of well-differentiated adenocarcinoma simulating fetal lung tubules which is a variant of pulmonary blastoma is reported. A 31-year-old female with an abnormal shadow in the right upper lung field detected by chest X-P during a follow-up for sarcoidosis during pregnancy underwent right upper lobectomy. Post operative histological diagnosis was well-differentiated adenocarcinoma simulating fetal lung tubules. This tumor might be a variant of pulmonary blastoma lacking the sarcomatous features and showing one-sided development of the epithelial component. However, it has been reported by various names, and classifications of pulmonary blastoma differed slightly depending on the reporter. There are also some discrepancies in the clinical course and prognosis of the tumor. Therefore it is considered that further examination of this tumor is necessary.

Adenocarcinoma↗
PubMed1993

[The significance of body weight measurement of esophageal cancer patients in intra- and postoperative fluid administration].

We tried to clarify the intra- and postoperative pathological state in resected thoracic esophageal cancer patients and analyze the particularity of fluid administration by measuring body weight at certain time serially. We studied 26 resected thoracic esophageal cancer patients between September, 1989 and January, 1991 who underwent an operation through right thoracotomy prior to laparotomy at the same time, and all cases were under general anesthesia combined with epidural anesthesia. We measured body weight preoperatively, just after operation, on the first, second and third postoperative days by means of LIFTER (Ted Hoyer & Co. Inc), and also calculated water balance and measured pressures and cardiac output by Swan-Ganz catheter in 19 cases. As a result, change in body weight was remarkable in resected thoracic esophageal cancer patients intra- and postoperatively. The peak of weight gain was noticed and they gained about 3 kilograms in weight on the 1st postoperative day, while in circulation hypovolemia was found on the data by means of Swan-Ganz catheter. There was a high correlation between rate of change in weight (kg/hr) and water balance (ml/kg/hr) (r = 0.91). We calculated insensible loss by the difference between water balance and body weight. It was about 1.73 intraoperatively, 0 postoperatively, 0.35-0.5 ml/kg/hr on from the 1st through the 3rd postoperative day. It is concluded that body weight measurement is a very easy, precise and useful bedside technique in the intra- and postoperative fluid administration of esophageal cancer patients, because it is very important not only to understand the circulation volume but also to know the interstitial fluid change.

Body Weight↗
PubMed1993

[Evaluation of the right ventricular function in postoperative esophageal cancer patients].

We evaluated the right ventricular function in pre- and post-operative esophageal cancer patients who had no complications after surgery by measurement of cardiopulmonary hemodynamics, right ventricular ejection fraction (RVEF) and right ventricular end-diastolic volume index (RVEDVI) using Swan-Ganz catheter and the thermodilution technique. The measurement of RVEF, RVEDVI and other cardiopulmonary hemodynamics were performed from the preoperative day to the 3rd postoperative day. The values of RVEF were stable about 40% from preoperative day to 3rd. RVEDVI was varied at 93.6 +/- 26.3 ml/m2 (preoperative day), 83.6 +/- 15.0 ml/m2 (after surgery), 70.2 +/- 10.6 mg/m2 (morning of the 1st POD), 95.6 +/- 19.4 ml/m2 (evening of the 1st POD), 103.2 +/- 17.9 m/lm2 (morning of the 2nd POD), 1108.3 +/- 14.2 ml/m2 (evening of the 2nd POD) and 112.4 +/- 31.0 ml/m2 (morning of the 3rd POD). The values of RVEDVI on the morning of the 1st POD were statistically lower than those at other times (p < 0.05). The values of RVEDVI were not correlated with mean pulmonary arterial pressure and pulmonary arteriolar resistance which were the afterload of the right ventricle. These data suggest that the right ventricular function of the patients who underwent esophagectomy with no complication does not change and that the changes of RVEDVI are influenced by the preload of the right ventricle.

Cardiac Output↗