Search PubMed⌕ Search

Biomedical subjects

Y Abe

Publications and source records attributed to Y Abe.

At least 703 records · Page 39Linked to original sources
PubMed1992

Effect of L-NG-nitro-arginine, inhibitor of nitric oxide synthesis, on autoregulation of renal blood flow in dogs.

The present experiments were designed to evaluate the importance of nitric oxide in the regulation of renal hemodynamics and the autoregulation of renal blood flow (RBF) in anesthetized dogs. RBF was measured by an electromagnetic flowmeter, and renal arterial pressure (RAP) was varied by an adjustable aortic clamp. The RAP-RBF relations were examined during the intrarenal infusion of saline or agents. The intrarenal infusion of L-NG-nitro-arginine (L-NNA, 40 micrograms/kg.min) at normal RAP decreased RBF and urine flow (UF), while the infusion of L-arginine.HCI (1 mg/kg.min) increased RBF and UF. Both agents did not affect the glomerular filtration rate and mean arterial pressure. The autoregulation of RBF was impaired during the L-NNA infusion. The L-arginine infusion did not affect autoregulatory efficiency. When L-NNA (40 micrograms/kg.min) and L-arginine were infused simultaneously into the renal artery, the autoregulation of RBF was maintained. However, a higher dose of L-NNA (200 micrograms/kg.min) impaired the autoregulation of RBF. These results suggest that the basal production and/or the release of nitric oxide contributes to the regulation of renal hemodynamics and urine formation. During the reduction of RAP, nitric oxide may play an important role in the autoregulation of RBF.

Animals↗
PubMed1992

Regional hemodynamic effects of betaxolol, a new selective beta 1-blocker, and atenolol in conscious spontaneously hypertensive rats.

Betaxolol is a new beta-blocker that has been reported to have beta 1-selectivity, and it is devoid of both membrane stabilizing action and intrinsic sympathomimetic action. The effects of betaxolol on systemic and regional hemodynamics were examined in conscious spontaneously hypertensive rats (SHR) by a microsphere method and compared with the effects of atenolol. A single oral administration of betaxolol at 1 and 10 mg/kg decreased the mean arterial pressure in a dose-dependent manner. At the same doses, atenolol also showed a similar but weak hypotensive effect. Both of these drugs at the high dose decreased cardiac output and heart rate and at the low dose, did not. Total peripheral resistance decreased by only betaxolol at the low dose. Betaxolol showed a tendency to normalize the hemodynamic abnormalities which were observed in the kidney, spleen and gastrointestinal tract of SHR, while atenolol did not. It should be noted that betaxolol increased the flow rate in the kidney, which may be explained by its direct vasodilatory action on renal blood vessels. In conclusion, betaxolol showed an antihypertensive action at the doses of 1 and 10 mg/kg, exhibited the characteristics of a beta 1-blocker and produced preferable effects on regional hemodynamics in SHR.

Animals↗
PubMed1992

Cell kinetic study of murine jejunal crypts during multiple doses per day.

We studied cell kinetics of mouse jejunal crypts during multiple fractionation using double labeling methods. Mice were irradiated to the total body once a day or twice a day. Fraction size was 2 Gy. Overall time was 1, 3 and 5 days. Labeling index (LI), duration of S phase (Ts) and potential doubling time (Tpot) were assessed next morning following the irradiation schedule. Mice were administered both bromo-deoxyuridine (BrdUrd) and 3H-Thymidine ([3H]dT) with a constant interval. Removed jejunum were stained with immuno-histochemistry and, then, processed for autoradiography. BrdUrd and [3H]dT LIs were the same and were increased up to 5 days despite the fractionation schedule. After 1 day following 2 fx/day, both Ts and Tpot decreased significantly. For 1 fx/day treatment, neither Tpot nor Ts changed. After 5 day following 1 and 2 fx/day, both Ts and Tpots were the same and Tpots were significantly shorter than that obtained from control. It seems that proliferative responses between 1 and 2 fx/day were different.

Animals↗
PubMed1992

N-(F-18)-fluoroacetyl-D-glucosamine: a new positron labeled pharmaceutical for cancer study.

In order to evaluate the role of hexosamine metabolism in tumor tissue, we studied the biodistribution of N-(F-18)-fluoroacetyl-D-glucosamine (FAGlu) in male Donryu rats bearing poorly differentiated hepatomas (AH109A and AH272). Compare with the former result of the high tumor uptake of FAGlu in C3H/He mice bearing well differentiated spontaneous hepatoma, the tumor uptakes of FAGlu in these tumors showed the lower values. This suggested that spontaneous hepatoma maintained a high activity of glucosamine metabolism, while poorly differentiated hepatoma had little activity. Metabolism of glucosamine in tumor tissue may be another marker for characterizing tumors. We also discuss the tissue distribution of new F-18 labeled hexosamines, N-(F-18)-fluoroacetyl-D-mannosamine and N-(F-18)-fluoroacetyl-D-galactosamine in tumor bearing rats.

Acetylgalactosamine↗
PubMed1992

Effects of capsaicin desensitization on nasal allergy-like symptoms and histamine release in the nose induced by toluene diisocyanate in guinea pigs.

Intranasal application of toluene diisocyanate (TDI) induced nasal allergy-like symptoms of sneezing and watery rhinorrhea and decreased the histamine content of the nasal mucosa in guinea pigs. However, in the animals pretreated with capsaicin (capsaicin desensitization) before sensitization with TDI, nasal allergy-like symptoms were not induced. Capsaicin desensitization also inhibited histamine release in the nasal mucosa induced by TDI. These findings suggest that antidromic impulses of capsaicin-sensitive sensory nerves stimulated by TDI cause histamine release from mast cells in the nasal mucosa, resulting in nasal discharge and sneezing in guinea pigs. Thus neurogenic inflammation via an axon reflex in the nose may contribute to the pathogenesis of vasomotor rhinitis.

Animals↗
PubMed1992

[Evaluation of renal function and prediction of renal functional recovery in children with unilateral hydronephrosis using renal pelvic urine].

In 29 children with unilateral hydronephrosis who underwent surgery at the age from 2 months to 15 years (27 patients with ureteropelvic junction stenosis and 2 with obstructive megaureter), beta 2-microglobulin (beta 2-MG), alpha 1-microglobulin (alpha 1-MG), N-acetyl-beta-D-glucosaminidase (NAG) and albumin were determined in renal pelvic urine from the hydronephrotic kidney to evaluate renal dysfunction accompanying urinary tract obstruction. Moreover, it was also examined whether it is possible to predict functional recovery of the hydronephrotic kidney on the basis of relation between these indices and pre- and postoperative changes in renal dimercaptosuccinic acid (DMSA) uptake rate. The values of beta 2-MG, alpha 1-MG, NAG and albumin in urine from the renal pelvis were high in 48%, 50%, 75% and 83% of the patients, respectively. Among the patients of one year and up, those with low preoperative DMSA uptake rate tended to have high values of beta 2-MG, alpha 1-MG and NAG. On the contrary, albumin level was high in 78% of patients who had good preoperative DMSA uptake rate. With respect to the relation between pre- and postoperative changes in DMSA uptake rate and each index, beta 2-MG and alpha 1-MG were high in 73% and 62% of patients who exhibited a marked increase in postoperative DMSA uptake rate. In patients without a remarkable change in DMSA uptake rate before and after surgery, on the other hand, the values of these were high only in 25% and 36%.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylglucosaminidase↗
PubMed1992

[A hundred cases of multiple primary neoplasms in association with genitourinary cancer].

There were 970 patients who were diagnosed as having genitourinary cancer at Yamagata Prefectural Central Hospital between 1975 and 1990, and of whom 100 cases (10.3%) had multiple primary malignant neoplasms in addition to their genitourinary cancer. They were compared with 220 patients having single genitourinary cancer and 274 having benign prostatic hypertrophy without past histories of cancer. The genitourinary organs involved with cancers included the prostate (50 patients), urinary bladder (43 patients), ureter or renal pelvis (15 patients) and kidney (7 patients). In the prostate cancer, the incidental carcinomas occupied 30%. The other organs accompanying the genitourinary cancers included the stomach, lung and colon. In patients of multiple primary cancers, single genitourinary cancer and benign prostatic hypertrophy, positive family histories for cancer were observed in 40.0%, 37.7% and 33.2%, respectively, with no significant difference between these groups. Histories of smoking were observed in 54.0%, 38.2% and 34.3% respectively, with significant difference between the multiple primary neoplasm patients and the other 2 groups (p < 0.01). There were two cases in whom the second cancer could be possibly caused by the exposure to radiation for the first cancer. No oncotherapeutic drugs or occupational exposure could be seriously suspected of the cause of the second cancers in the present cases.

Adult↗
PubMed1992

[Secretion of atrial natriuretic peptide during artificial pacing: assessments including the influence of ventriculoatrial conduction].

Secretion of atrial natriuretic peptide (ANP) depends on the atrial wall distension which may be caused by ventricular pacing. This study was designed to assess the differences in plasma ANP level between DDD and VVI pacing. We measured ANP from venous blood samples using radio-immunoassay in patients with the sick sinus syndrome (n = 8) and atrioventricular block (n = 2) following DDD implantation. Measurement was made under control conditions during DDD and 15-180 min after the pacing mode was changed to VVI and 60 min after returning to DDD. Serum epinephrine (E), norepinephrine (NE), renin (R) and aldosterone (A) levels were also measured prior to and every 30 min after pacing mode changes. The plasma ANP concentration changed from 71.3 pg/ml (normal value) with DDD to 126.8 (15 min), 180.6 (30 min), 221.8 (60 min), 219.2 (90 min), 270.1 (120 min), 145.4 (150 min) and 115.1 pg/ml (180 min) with VVI. It increased markedly, then gradually decreased. It returned to the control value (66.6 pg/ml) in 60 min with DDD, and it reached the peak level with VVI within 60-120 min, and the peak was significantly higher than that for DDD. The increase related to the retrograde ventriculoatrial conduction during VVI pacing. There was no significant change in the NE, E, R and A concentrations. Systolic blood pressure decreased 15 mmHg in VVI and returned to normal by DDD. These results indicated that plasma ANP levels is elevated by VVI pacing, though it was not explained by ventricular pacing alone.

Aged↗
PubMed1992

[Therapeutic value of hepatectomy and transcatheter arterial embolization (TAE) for hepatocellular carcinoma].

Therapeutic value of hepatectomy and TAE was evaluated retrospectively in 150 hepatectomized and 117 non-hepatectomized patients of hepatocellular carcinoma (HCC). Operative death was seen in 5 patients. Cumulative 5 years survival rate and disease free cumulative 5 years survival rate of the 145 hepatectomized patients were 35.4 per cent and 23.6 per cent respectively. These survival rates were significantly affected by tumor size, intrahepatic metastasis (IM) and vascular invasion (Vp). But the influences of tumor margin (TW) and curative resection (relative curative or relative non-curative) were slight. Ninety-two patients (69:dead, 23:alive) had tumor recurrences. TAE was performed in 56 out of 92 patients effectively and 2 years survival rate was 31.5 per cent. Overall cumulative 5 years survival rate of non-hepatectomized patients was 6.6 per cent, but this group showed a more reduced hepatic reserve and more advanced tumor stage. Six patients treated by TAE survived more than 4 years. Hepatectomy is a first option for the treatment of HCC since complete cure may be estimated. However, because of operative risk and higher recurrence rate, use of current multidisciplinary treatment including TAE is necessary for the prognostic improvement of HCC with or without hepatectomy.

Aged↗
PubMed1992

Effects of the calcium antagonist manidipine on renal hemodynamics and function in dogs: comparison with nifedipine.

The renal effects of manidipine, a new dihydropyridine calcium antagonist, were compared with those of nifedipine in anesthetized dogs. Intrarenal administration of manidipine 1 and 5 micrograms/kg resulted in prolonged (120 min) increases in renal blood flow (RBF), glomerular filtration rate (GFR), urine flow (UF), and urinary excretion of electrolytes. In contrast, the renal effects of nifedipine disappeared within 5 to 10 min after administration. These results demonstrate that manidipine is a long-acting calcium antagonist. Manidipine proportionally increased RBF and GFR. As a result, filtration fraction was kept constant. The changes in afferent and efferent arteriolar resistance suggested that manidipine increases GFR via dilation of afferent arterioles with subsequent elevation of filtration pressure in the glomeruli. Manidipine also proportionally increased Tc H2O and Cosm; Tc H2O/Cosm did not change throughout the experiments. In addition, manidipine increased the fractional excretion of sodium from the distal tubule which was calculated from the lithium and sodium clearance. The mode of diuretic action of manidipine most likely involves inhibition of sodium reabsorption in the proximal and distal tubules, except the medullary portion of the ascending limb of Henle. The renal vascular site of action of manidipine might be the afferent arteriole.

Anesthesia↗
PubMed1992

[CD7 (+) stem cell leukemia presenting different phenotypes in lymph node and bone marrow].

A 27-year-old male with systemic lymphadenopathy was diagnosed as lymphoblastic-type lymphoma by inguinal lymph node biopsy in September, 1990. Bone marrow at the initial diagnosis contained 55.4% lymphoblasts with a phenotype of peroxidase (-), CD7 (+), CD4 (-), CD8 (-). Lymphadenopathy and lymphoblasts in bone marrow disappeared after MACOP-B therapy. In December, 1990, however, the patient again noticed swelling of cervical lymph nodes. At this time, the bone marrow contained 36.4% myeloblasts with a peroxidase (+), CD7 (+), CD13 (+), CD33 (+) phenotype. Cytogenetic and genetic study revealed that the lymphoblasts at the initial diagnosis and the myeloblasts at relapse shared an common abnormal karyotype, 11p-, and the same rearranged band of T-cell receptor delta, gamma, beta genes, suggesting that these two blasts originated from the same clone. The blasts obtained from the cervical lymph node at relapse were still negative for peroxidase, in contrast to the blasts from bone marrow. These findings suggest that this leukemia originated from a stem cell and differentiated along multilineage pathways.

Adult↗
PubMed1992

[Plasma lipid peroxides in the operation of esophageal cancer].

Lipid peroxides are formed by autooxidation of polyunsaturated fatty acids found primarily in cell membranes. An increase level of lipid peroxides in the tissue therefore reflects membrane damage. We reported that water immersion restraint rats caused significant increase of gastric mucosal lipid peroxide which reflected on gastric mucosal injury. The gastric mucosal injury is also known as the post-operative complication due to physical stress. So we studied plasma lipid peroxide and its related substances in the operation of esophageal cancer. Lipid peroxide levels increased significantly in pre- and post-operation but temporal decrease was found during the operation. Vitamin E is thought to be an important structural component of biologic membranes and is believed to act as a free radical scavenger in lipid peroxidation. Vitamin E also increased in the patients of esophageal cancer and decreased significantly during the operation. Superoxide dismutase changed frequently during the operation but there was no deficit tendency in its changes. Catalase levels also changes frequently and showed temporal but statistical elevation after the operation. These results indicated that lipid peroxidation may contribute to the development of organic damage in the operation of esophageal cancer.

Catalase↗
PubMed1992

[A successful operative case of congenital mitral stenosis associated with double outlet right ventricle, patent ductus arteriosus, persistent left superior vena cava and severe pulmonary hypertension in adult].

A 29-year-old woman, who was diagnosed as congenital mitral stenosis associated with DORV, PDA, PLSVC and severe pulmonary hypertension, was reported. The mitral valve, consisting of leaflet dysplasia, shortened and thickened chordae tendineae, obliteration of interchordal spaces, under-development of papillary muscle, and stenotic supravalvular membrane, was replaced with 25 SJM prosthesis. Simultaneously, patch closure of VSD and intrapulmonary direct closure of PDA was performed. Her postoperative course was uneventful and systolic pulmonary arterial pressure fell down from 95 mmHg to 56 mmHg. She is doing well after correction. To our knowledge, this is very rare corrective case with congenital mitral stenosis in adult to be reported in the literature in Japan.

Adult↗
PubMed1992

[A case of adult pulmonary supravalvular membranous stenosis which was successfully treated by percutaneous transluminal balloon dilatation].

We report a case of adult pulmonary supravalvular stenosis which was successfully treated with percutaneous transluminal balloon dilatation (PTBD). A 42-year-old man was admitted for a heart murmur and abnormal findings in the screening chest roentgenogram. Having no symptoms on admission, his physical activity was evaluated as Class I according to the classification of the New York Heart Association. A systolic murmur (Levine III/VI) with split second sound was audible at the left sternal border in the 3rd intercostal space. Chest roentgenogram revealed 57% of the cardio-thoracic ratio and no signs of increased pulmonary vascular markings. ECG showed incomplete right bundle branch block. Echocardiography and right ventriculography visualized the supravalvular membranous structured stenosed pulmonary artery 1cm above the pulmonic valve. Systolic pressure gradient between the right ventricle and the distal main pulmonary trunk was 54mmHg. The patient was diagnosed as having pulmonary supravalvular membranous stenosis. PTBD was applied using Inoue balloon catheter, where inflation was initiated from approximately 120% of pulmonary arterial diameter and terminated at 150%. This procedure decreased systolic pressure gradient from 54mmHg to 36mmHg without complication. After PTBD right ventriculography demonstrated that a part of the membranous structure had become floppy and movable. Pulmonary arterial diameter was unchanged. We considered that PTBD tore the membranous structure, which consequently resulted in the decrease of systolic pressure gradient. Systolic murmur diminished to Levine II/VI. Six months later, cardiac catheterization showed no change in systolic pressure gradient compared with that immediately after PTBD. This is the first report on pulmonary supravalvular membranous stenosis successfully treated with PTBD.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Transforming growth factor-beta 1 down-regulates expression of membrane-associated lymphotoxin and secretion of soluble lymphotoxin by human lymphokine-activated killer T cells in vitro.

Lymphokine-activated T killer lymphocytes (T-LAK) are important effector cells in various diseases of tissue destructive reactions. They require stimulation with various cytokines to proliferate and mature into function effector cells. We have examined the role of various endogenously and exogenously added cytokines, and tumor necrosis factor (TNF)/lymphotoxin (LT) receptors in this process in vitro. The present report is a continuation of these studies. We found that human T-LAK cells express membrane-associated LT (mLT) but not TNF, and secrete high amount of soluble LT (sLT) but low levels of TNF. When added to the initial cultures or immature T-LAK cells, transforming growth factor-beta 1 (TGF-beta 1) suppressed both mLT expression and sLT secretion by 30-40%. Coculture of mature T-LAK cells with TGF-beta 1 caused 35% down-regulation of both mLT expression and sLT secretion after 18 h of incubation. Kinetic experiments indicated reduction of LT mRNA synthesis could occur in as little as 1 h when cocultured with 5 ng/ml of TGF-beta 1. TGF-beta 1 also reduced mLT induced T-LAK cell cytolytic activity on L929 cells in vitro. It appears TGF-beta 1 can down-regulate LT mRNA syntheses, mLT expression, and sLT secretion of human T-LAK cells in vitro.

Cells, Cultured↗
PubMed1992

[Two cases of acute promyelocytic leukemia in pregnancy and the effect of anthracyclines on fetal development].

Two patients with acute promyelocytic leukemia (APL) in 2nd and 3rd trimester of pregnancy are reported on. Case 1: 38-year-old female consulted our hospital because of bleeding tendency and pancytopenia in April, 1988. She was diagnosed as having APL with disseminated intravascular coagulopathy (DIC) and was found to be in the 14th week of gestation. Combined chemotherapy (BHAC-DMP) including the total dose (440 mg) of daunorubicin (DNR) resulted in intrauterine fetal death at 19 weeks of gestation. The fetus was severely anemic and the bone marrow was hypoplastic. Case 2: A 27-year-old female was diagnosed as having APL with DIC at 29 weeks of gestation. BHAC-DMP including 440 mg DNR achieved complete remission. At 35 weeks of gestation, she delivered a normal infant by Caesarean section. The child had normal hematological findings and showed normal growth. Both cases developed APL accompanied by DIC during pregnancy and were treated with a similar regimen including high dose of anthracyclines. Case 2 treated in the late period of gestation delivered a normal infant, while fetal death resulted in case 1, treated in the early period of gestation. We reviewed the literature regarding chemotherapy using anthracyclines during pregnancy.

Adult↗
PubMed1992

[Histological evidence of prolonged coronary artery spasm in a necropsy case of recurrent myocardial infarction].

A 69-year-old male had acute inferior infarction during an operation of an aneurysm of the abdominal aorta and died from multiple organ failure 3 weeks after the operation. His initial coronary angiogram (CAG) showed no significant stenosis, but repeated CAG showed that the patients had developed a prolonged spasm in the mid-portion of the right coronary artery. Histologically, we observed eccentric luminal narrowing with atheromatous plaque where the spasms had been demonstrated, and a "waving form" of elastic fibers accompanied by intimal thickening in the opposite site of the atheromatous plaque. These findings suggest that organic stenosis may be underestimated angiographically because of compensatory enlargement of the non-atheromatous site in some patients with coronary artery spasm, and prolonged spasms may augment organic stenosis by following intimal thickening.

Aged↗