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T Koyanagi

Publications and source records attributed to T Koyanagi.

At least 199 records · Page 11Linked to original sources
PubMed1994

Concentration factors for Cs-137 in marine algae from Japanese coastal waters.

Concentration factors (CF: Bq.kg-1 in wet algae/Bq.kg-1 in filtered seawater) for Cs-137 in Japanese coastal algae, were investigated during 1984-1990. Cs-137/Cs(stable) atom ratios were also examined to clarify the distribution equilibrium of Cs-137 in marine algae and sea water. The CFs in marine algae were within the range of 5.4 approximately 92, and the geometric mean of CF was 28 +/- 2 (standard error) in Japanese coastal species. The CFs in edible species were within the range of 5.4 approximately 67, and the geometric mean of CF was 26 +/- 4 (standard error). The values of Cs-137/Cs atom ratios in marine algae and sea water indicated that Cs-137 reached an equilibrium state in partition between algae and sea water. Therefore, the CF value obtained in the present study can be regarded as an equilibrated value. Our results showed that the CF for Cs-137 in Japanese coastal algae were consistent with the Japanese guideline CFs, but were smaller than the recommended value by IAEA.

Cesium Radioisotopes↗
PubMed1994

[Bladder calculus after augmentation ileocystoplasty in children].

Of 12 children who had undergone augmentation ileocystoplasty for treatment of neurogenic bladder, 3 developed bladder calculi 9 to 19 months after the operation. All these 3 children had simultaneously undergone procedure to ensure urinary continence together with ileocystoplasty, and postoperative persistent bacteriuria was found in these 3 children. Component of bladder calculi was magnesium-ammonium phosphate in 2 and calcium phosphate in the other child, and all were successfully removed by endoscopic lithotripsy. These data suggest that postoperative persistent bacteriuria as well as procedures to ensure urinary continence might play a role in the formation of bladder calculus after augmentation cystoplasty.

Adolescent↗
PubMed1994

[Analysis of growth fractions of renal cell carcinoma by the monoclonal antibody Ki-67].

The monoclonal antibody Ki-67 recognizes a human nuclear antigen that is present in proliferating cells (G1, S, G2 and M cycling stages of cell division) exclusively, but is absent in G0 cycling stage. We performed immunohistochemical analysis of renal cell carcinomas using Ki-67 antibody, and investigated the relationship between the proportion of Ki-67 positive cells and pathological findings of renal cell carcinomas. The tissues were obtained from 36 patients with renal cell carcinoma who underwent radical nephrectomy. Cryostatfrozen sections were cut at 5 microns and stained with avidin-biotin-peroxidase complex method. The percentage of Ki-67 positive cancer cells to the total amount of cancer cells was expressed as growth fraction (GF). We obtained the following results with regard to the relationship between GF and pathological findings of renal cell carcinomas. 1) GFs in pathological grades were 6.58 +/- 4.57% (mean +/- SD) for grade 2 (n = 13) and 1.20 +/- 0.70% for grade 1 (n = 21). GF in grade 2 was significantly higher than that in grade 1 (p < 0.01). GF for Grade 3 (n = 2) were 9.2% and 27.8% respectively. 2) GFs in the pathological stages were 8.12 +/- 7.64% for pT3 (n = 13) and 1.84 +/- 1.30% for pT2 (n = 23). GF in pT3 was significantly higher than that in pT2 (p < 0.01). 3) GFs in the cancers with and without lymph node involvement were 13.84 +/- 8.48% (n = 5) and 2.80 +/- 2.74% (n = 27), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoma, Renal Cell↗
PubMed1994

[Diagnosis of prostate cancer by means of the ratio of prostate specific antigen/gamma-seminoprotein (P/S ratio)].

Prostate specific antigen (PSA) and gamma-seminoprotein (gamma-Sm) are revealed to be the same protein. However, the serum concentrations of PSA and gamma-Sm in the same samples are frequently different. We previously measured a ratio of serum PSA concentration and gamma-Sm concentration (P/S ratio), and evaluated its usefulness for diagnosis of prostate cancers. In this paper, we tried to determine the cutoff value which brings better efficiency and diagnose prostate cancer by means of P/S Ratio. Between April 1988 and September 1992, 221 men underwent prostatic biopsy and/or TUR-P, and were diagnosed pathologically. Of 221 patients, 130 were diagnosed as BPH, prostatis or normal prostate (no cancer; NC) and 91 were diagnosed as prostate cancer (CaP). 1) The mean +/- SD of P/S ratio in 130 patients with NC was 0.919 +/- 0.563. While, the mean +/- SDs of P/S ratio were 12.447 +/- 44.353 in 91 patients with CaP and 2.052 +/- 0.751 in 39 Cap patients with serum PSA level of < or = 10 ng/ml. The mean P/S Ratios in CaP patients with serum PSA of < or = 10 ng/ml as well as in all CaP patients were significantly higher than those in NC patients (p < 0.0001). 2) When the cutoff value of P/S Ratio was determined to be 1.45, the highest efficiency (= sensitivity x specificity divided by 100), 83.4, was obtained. The sensitivity and specificity were 91.2% and 91.5%, respectively as a cutoff value of 1.45.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Neoplasm↗
PubMed1994

[Resection of intra-atrial tumor thrombi from renal malignant tumors with the use of cardiopulmonary bypass and temporary exsanguination. An experience based on 4 cases].

We report 4 patients, 1 female and 3 males aged 26-74 years, who underwent surgical treatment for renal malignant tumors with supradiaphragmatic extension into the vena cava. All of their tumor thrombi extended to the right atrium as confirmed by magnetic resonance imaging. The distinctive symptom was liver dysfunction caused by disturbance of the hepatic vein drainage in two patients. However, there was no common symptom in these 4 patients. Preoperative metastasis was found only in the female, whose metastasis was solitary in the lung and seemed to be able to be removed easily after radical nephrectomy. All of these 4 patients had radical nephrectomy and removal of the tumor thrombi with the use of cardiopulmonary bypass and temporary exsanguination. In 3 of these patients, the liver was mobilized to expose the retrohepatic vena cava by incision of the falciform, triangular and coronary ligaments. Two patients with vena caval wall invasion had vena cavectomy and an artificial vascular graft was then sutured to replace the caval wall in one of them. Preoperative liver dysfunction was gradually improved after operation and completely recovered about 1 week later. A postoperative complication, wound infection, occurred in only one patient. Pathological examination revealed renal cell carcinoma in 3 patients and nephroblastoma in the remaining one. In renal cell carcinoma, both patients without distant metastasis were alive about 15 months postoperatively. However, the one with lung metastasis died with newly appeared multiple metastases 9 months postoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

[Transcranial Doppler measurement of middle cerebral artery blood flow during continuous retrograde cerebral perfusion].

This is the first report of cerebral blood flow measurement with transcranial Doppler (TCD) during aortic arch reconstruction using continuous retrograde cerebral perfusion (CRCP) with deep hypothermia. Cerebral blood flow velocity was measured in 6 patients. CRCP was performed via the superior vena cava (SVC) at 30 cmH2O of internal juglar vein pressure and at 18 degrees C or lower of minimum bladder temperature. During the operation, the flow velocity of the middle cerebral artery (MCA) was continuously measured with TCD fixed on the temple. The cerebral blood flow during CRCP was different in each of the 6 patient. The retrograde MCA flow could be measured during CRCP in 3 patients, and the flow velocity was 11-60% of the MCA flow velocity before cardiopulmonary bypass. In the other 3 patients, retrograde MCA flow could not be detected during CRCP, but antegrade MCA flow could be found after antegrade perfusion was resumed. The antegrade flow velocity right after CRCP became more than the MCA flow before CRCP, which was regarded as a reaction due to cerebral ischemia. All the patients awoke within several (2-9) hours after operations and had no permanent neurological complications. But 2 patients developed drowsiness for several days after the operations; their CRCP times were 127 and 131 minutes. It is concluded that CRCP is a simple technique for brain protection, but the cerebral blood flow during CRCP is a simple technique for brain protection, but the cerebral blood flow during CRCP is different in each patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Hormonal abnormalities were improved by weight loss using very low calorie diet in a patient with polycystic ovary syndrome].

A 27-year old woman was admitted to our hospital because of oligomenorrhea, hirsutism and obesity. Her menstrual period has been irregular since she was 14 years old. Her weight increased rapidly after the age of 15 and she became obese. Hirsutism was noticed at the age of 16. The diagnosis of polycystic ovary syndrome was made on her illness through the endocrinological examinations: (1) The response of LH to LH-RH administration was much higher than that of FSH. (2) The concentration of plasma testosterone was increased. (3) Plasma level of E2 was decreased while that of E1 was increased. (4) CT scan showed bilateral ovarian cyctic masses. In addition, hyperinsulinemia was observed during the 75g glucose tolerance test and the presence of insulin resistance was suggested. As she was overweight (BMI; 33.6 kg/m2), weight loss was expected to improve her hormonal abnormalities. She went on a very low calorie diet of 420 kcal/day (Optifast, Sandoz, USA). When she lost around 9kg of weight, her menstruation period started that has not been observed for the previous 5 months. Plasma levels of LH, FSH and testosterone were lowered following the weight loss. The responses of LH to LH-RH and IRI to glucose were decreased as well. She left the hospital after the second menstruation occurred at the proper period. From these results, the importance of weight loss was suggested in overweight patients with polycystic ovary syndrome. The benefit of very low calorie diet was also noticed since it brought a rapid weight loss as well as rapid improvements of hormonal abnormalities.

Adult↗
PubMed1994

[Is extensive usage of arterial grafts in revascularization of the circumflex appropriate?: comparative study with the saphenous vein].

From September 1975 to March 1992, 584 patients underwent coronary artery bypass grafting (CABG) including revascularization of the circumflex artery (LCX) with either saphenous vein (Group S, n = 496) or arterial grafts (Group A, n = 88). Group S was divided into two subgroups. Group S I is the patients who underwent CABG before April 1988, when the first case of arterial revascularization of the LCX, and Group S II is the patients who underwent CABG after April 1988. No significant differences were noted in early mortality, late mortality, or event free curve among three groups. Although graft flow was significantly less in Group A (27.8 +/- 12.8 ml/min) than Group S (60.0 +/- 35.7 ml/min), the patency rate was better in Group A (94.3%) than Group S I (88.6%) or Group S II (87.7%). The proportion of usage of arterial grafts in revascularization of the left anterior descending artery (LAD) was smaller in Group A (65.5%) than Group S II (80.3%), but the patency rate was acceptably good in both groups (Group A: 98.8%, Group S II: 99.5%). These findings justify extensive usage of arterial grafts to the LCX area under proper assignment of grafts to obtain good patency rate and long-term results with keeping quality of revascularization of the LAD area.

Abdominal Muscles↗
PubMed1994

[Seventy coronary reoperations: indication and results].

Seventy consecutive patients undergoing reoperative coronary artery bypass grafting (re-CABG) were reviewed to determine operative and late results, and indications of re-CABG. There was no operative death (within 30 days after re-CABG) but 3 (4.3%) hospital deaths in patients with emergency re-CABG. Although graft patency rate was acceptable (92.5%), the rate of complete revascularization was only 70%. Including non-cardiac death, the actuarial survival rate at 8 years was 88.2%, and event free rate including all deaths, the third time CABG, PTCA and myocardial infarction was 78.4% at 8 years. At re-CABG, no old arterial grafts and only 4.7% (2/43) of the old saphenous vein grafts to the left anterior descending artery (LAD) were patent without stenosis. Success rate of PTCA was 90.9% in the saphenous vein graft and 95.2% in the internal thoracic artery graft. Restenosis rate was significantly higher in the saphenous vein graft (55%) than the arterial graft (10%) (p < 0.001), and restenosis rate of repeat PTCA to the saphenous vein graft was 100%. In conclusion, re-CABG should be mainly indicated to the patients with persistent symptom and diseased grafts to the LAD, and PTCA to the old saphenous vein graft should be limited to once to avoid acute deterioration requiring emergency re-CABG.

Adult↗
PubMed1994

[Coronary intervention in patients less than 40 years of age].

Forty-eight patients less than 40 years of age who underwent coronary intervention (coronary artery bypass grafting, CABG or percutaneous transluminal coronary angioplasty, PTCA) were identified and compared with a control group (patients more than 40 years of age who underwent coronary intervention). In addition, the treatment of hyperlipidemia after coronary intervention was studied in patients who required re-intervention and in those who were event free. There were no early nor late deaths and good early results were obtained in young patients, but late follow-up demonstrated that a re-intervention rate in young CABG patients was significantly higher than that in patients aged over 40 years (23.3% vs 9.3%), while in PTCA patients it was also higher in younger patients than in older patients (5.6% vs 1.3%). However, early results in PTCA patients showed the restenosis rate in young patients was significantly lower than that in older patients (7.7% vs 40.7%). Event free curve showed that earlier re-intervention was necessary for PTCA patients than for CABG patients. Hyperlipidemia was not well controlled by treatment in either group. The use of arterial grafts will improve the late results of younger patients. The patency of grafts and the quality of life of young patients should be the focus of future investigation.

Adult↗
PubMed1994

Possible mechanism of vascular damage in pre-eclampsia.

To clarify the pathophysiological changes of pre-eclampsia, we investigated the injurious effect of sera from women with pre-eclampsia on cultured endothelial cells, vascular smooth muscle cells and fibroblasts. We obtained serum samples from 32 Japanese women, including 10 healthy nonpregnant women, 12 normal pregnant women and 10 women with pre-eclampsia. Cell injury was measured by the release of radiolabelled chromium from the cells into the culture medium. The mean values +/- SD of percentage chromium release from endothelial cells in normal nonpregnant, normal pregnant and pre-eclamptic subjects were 8.5 +/- 2.4, 8.8 +/- 2.1 and 19.7 +/- 3.6%, respectively. Sera from women with pre-eclampsia demonstrated significantly greater endothelial cell injury than did sera from normal pregnant and nonpregnant subjects. However, normal pregnant and pre-eclamptic subjects did not differ with respect to both vascular smooth muscle cell injury and fibroblast injury. These results indicate that a serum cytotoxic to endothelial cells is present in pre-eclampsia and that this activity has a cellular specificity for endothelial cells.

Adult↗
PubMed1994

Extensive use of arterial grafts for coronary artery bypass grafting in Japanese patients.

Between August 1985 and December 1992, 298 patients underwent coronary artery bypass grafting with two or more distal anastomoses using arterial grafts. There were 279 males and 19 females, with an average age of 58.4 years. Thirty-one patients underwent sequential bypass with the left internal mammary artery. The remaining 267 patients received two or more arterial grafts. The three major combinations were the left and right internal mammary arteries (120 cases), the left internal mammary and right gastroepiploic arteries (100 cases) and the left and right internal mammary and right gastroepiploic arterial (43 cases). An additional saphenous vein bypass was constructed in 113 patients, and the average number of distal anastomoses was 2.70 per patient. The operative mortality rate was 1.0% (three patients), and hospital mortality rate 0.7% (two patients). Angiographic patency rate was 97.9% in arterial grafts and 94.3% in venous grafts. There were seven late deaths (three due to cardiac causes), and the 7-year actuarial survival and event-free rates were 92.8% and 86.6%, respectively. In conclusion, the extensive usage of arterial grafts in Japanese patients was accompanied by excellent long-term results without increased operative mortality and morbidity.

Adolescent↗
PubMed1994

[Sequential coronary artery bypass grafting using arterial conduits].

Fourty one patients underwent sequential coronary artery bypass grafting (CABG) using in situ arterial conduits as sequential bypass grafts. Included were sequential bypass from diagonal branch to left anterior descending artery (LAD) using the left internal thoracic artery (LITA) in 29 patients, skip bypass from segment 7 to segment 8 (AHA classification) of LAD using LITA in 5 patients and sequential bypass to the distal branches of the right coronary and circumflex arteries using the right gastroepiploic artery in 7 patients. There were no hospital deaths and only one patient who received skip bypass died of heart attack a couple of years after-operation. The overall patency rate was 95% (77/81). Reoperations were done in three patients all of whom received sequential bypass using LITA. It was characteristic that the distal anastomoses of sequential graft occluded in 7 of 9 patients and those proximal anastomoses were patent. This procedure is one available and reliable option for multiple coronary bypass grafting. However, if the arterial conduits are too small in caliber to use for sequential grafts, they should be used as individual grafts.

Adult↗
PubMed1994

Coronary artery bypass grafting with the right gastroepiploic artery and evaluation of flow with transcutaneous Doppler echocardiography.

From December 1988 to December 1992, 174 patients (160 men, 14 women, mean age 59.7 years, range 38 to 79 years) underwent coronary artery bypass grafting with the right gastroepiploic artery. The graft was anastomosed to the right coronary artery (n = 137), the circumflex artery (n = 18), the left anterior descending artery (n = 23), and the diagonal artery (n = 1). Three early deaths (1.7%) and one late death (0.6%) occurred. Graft patency and flow were evaluated noninvasively in 44 of the patients, selected at random between 1990 and 1993. They underwent transcutaneous Doppler echocardiographically to detect postoperative gastroepiploic artery flow. The patients were divided into two groups on the basis of the angiographic study: group I, good patency (n = 38); group II, poor flow in the graft or more than 75% stenosis of the anastomosis (n = 6). Biphasic Doppler flow signals were identified in 39 patients (88.6%) (group I, 35/38; group II, 4/6). The ratio of diastolic to total flow measured by time-velocity integral was 0.68 +/- 0.07 in group I and 0.32 +/- 0.09 in group II (p < 0.001). We conclude that the right gastroepiploic artery is an effective graft and that Doppler echocardiography may be a useful tool to noninvasively evaluate the patency and flow of the gastroepiploic artery graft as a coronary artery graft.

Adult↗
PubMed1994

[Combined operations of coronary artery bypass grafting using the right gastro-epiploic artery and other abdominal operation].

We carried out combined operation of coronary artery bypass grafting using the right gastro-epiploic artery (GEA) and other abdominal operation in four patients. The abdominal operation were one total gastrectomy for double early gastric cancer, one bypass with Y-shaped graft for arteriosclerosis obliterans in iliac region and two peritoneal dialysis for chronic renal failure. There were no early death. The postoperative course was uneventful without any mediastinitis or other infectious events. Doing careful maneuver, we can use the GEA for grafts in such cases.

Aged↗