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Biomedical subjects

R Takeda

Publications and source records attributed to R Takeda.

At least 361 records · Page 20Linked to original sources
PubMed1985

Serum antioxidant activity in uremic patients.

Serum antioxidant activity (AOA) was examined in 35 healthy subjects and 111 patients with chronic renal failure (CRF), consisting of 13 patients in the predialysis stage, 11 requiring the start of regular dialysis therapy (RDT) and 87 undergoing RDT. Serum AOA was determined by assaying serum activity to inhibit malondialdehyde (MDA) generation. AOA levels were significantly lower in CRF patients, and the lowest levels were noticed in patients with uremic symptoms requiring the start of RDT. These levels were restored to a subnormal level during RDT. Defective serum AOA appears to be an endogenous metabolic consequence in uremia. Sera with low AOA tended to show high MDA levels, indicating that patients with low serum AOA were susceptible to cellular injury by lipid peroxidation. It is proposed that defective serum AOA may contribute to a certain uremic toxicity through peroxidative cell damage.

Adult↗
PubMed1985

Effect of sodium intake on the excretion of urinary natriuretic factor in essential hypertensives.

A simplified method for the determination of natriuretic factor in the urine as measured by digoxin-like substance was studied. Digoxin-like substance in the urine was estimated by RIA using anti-digoxin antibody after being extracted by reversed phase cartridge column but without gel filtration. The values found by radioimmunoassay (RIA) yielded a significant correlation with those of the inhibitory effect of Na-K-ATPase activity which was measured by biochemical assay as described by Hamlyn et al. Using this RIA method, the effect of salt intake on natriuretic factor in urine was studied in patients with essential hypertension. The natriuretic factor on a high sodium diet (NaCl 20 g/day for three days) increased approximately 1.5 times, as compared to those on a low sodium diet (NaCl 3 g/day) (p less than 0.05). The Natriuretic factor showed a positive correlation with urinary Na excretion (P less than 0.050) when the patients were placed on ad. lib. sodium diet. From these results, it is suggested that secretion of natriuretic factor in the urine might be regulated in part by salt intake.

Aldosterone↗
PubMed1985

Cushing's syndrome associated with bilateral adrenal adenomas.

The fifth case of Cushing's syndrome with bilateral adrenocortical tumours is described. By the hormonal dynamic studies both tumours have been shown to be autonomous in the secretion of cortisol. Histopathologically, both tumours were identified as benign adrenocortical adenomas without nodules, and the right one was a so-called black adenoma. A high concentration of cortisol was obtained from both tumour tissue extracts. The differential diagnosis of Cushing's syndrome due to bilateral adrenocortical adenomas from primary adrenocortical nodular dysplasia is briefly discussed.

Adenoma↗
PubMed1985

Reversible hyperkalemia induced by flufenamic acid in asymptomatic hyporeninemic patient.

Reversible hyperkalemia induced by flufenamic acid in an asymptomatic hyporeninemic patient with IgA nephropathy is reported. Flufenamic acid, 600 mg daily, was given for four months to a 64-year-old woman with biopsy proven IgA-nephropathy. This produced hyperkalemia, hypertension and congestive heart failure with slowly progressive renal impairment. We conclude that a further suppression of the renin angiotensin system causing selective hypoaldosteronism together with the nephrotoxic effects of this drug may have been responsible for hyperkalemia in this patient.

Female↗
PubMed1985

Participation of vascular prostacyclin for the pathogenesis of experimental glucocorticoid hypertension in rats.

Prostacyclin (PGI2) generation in the mesenteric arteries from dexamethasone acetate (DX) and deoxycorticosterone acetate (DOCA) treated rats was assessed by ex vivo perfusion method. PGI2 generation which was measured by 6-keto-PGF1 alpha output in the perfusate was significantly reduced in DX treated rats at prehypertensive stage both under the basal conditions and in response to angiotensin (ANG) II, whereas in DOCA group rats, vascular PGI2 production was not impaired. Plasma renin activity (PRA) was significantly suppressed in DOCA but normal in DX rats. These results suggest that the reduced PGI2 generation in the resistance arteries may contribute to the development of hypertension induced by DX.

Angiotensin II↗
PubMed1985

Induction of tumoricidal activity of polymorphonuclear leukocytes by a linear beta-1,3-D-glucan and other immunomodulators in murine cells.

The cytotoxic activity of polymorphonuclear leukocytes (PMN) against tumor cells induced in vitro by antitumor immunomodulators was examined by a 51Cr release cytotoxicity assay. Among 28 immunomodulators and other agents thus far tested, only beta-1,3-glucan from Alcaligenes faecalis var. myxogenes IFO 13140, Bacillus Calmette-Guérin, Propionibacterium acnes, zymosan A, and Nocardia cell wall skeleton were found to cause induction. The cytotoxic activity of PMN with the beta-1,3-glucan was very high, almost 100% cytolysis being observed at an effector:target ratio as low as 3. The other four potent immunomodulators had effects very similar to that of the beta-1,3-glucan. All five tumor cell lines tested, MM46, MM48, MH134, EL-4, and YAC-1, were lysed, whereas normal spleen and thymus cells and PMN were not. Of four types of effector cells tested, PMN and casein-induced macrophages were effective, whereas resident macrophages and J774 cells were not effective. The cytotoxic activity of PMN was greater than that of induced macrophages, although both were induced by casein. From results on the polysaccharides tested, a linear beta-1,3-glucan structure and a minimum number average degree of polymerization of 125 of the beta-1,3-glucan seemed to be required for induction of cytotoxicity of PMN. The cytotoxic features of PMN and possible chemical structures of antitumor polysaccharides for induction of cytotoxicity are discussed.

Adjuvants, Immunologic↗
PubMed1985

Effects of insulin on hypercholesterolemia in the streptozotocin-induced diabetic rats fed a high cholesterol diet.

The effect of dietary cholesterol (Ch) on plasma lipoprotein and apolipoproteins (apo) in diabetic rats was investigated. Ch-fed diabetic rats were severely hypercholesterolemic and hypertriglyceridemic. They had higher concentrations of very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL) and low density lipoprotein (LDL). Concentration of high density lipoprotein (HDL) was decreased. beta-VLDL increased predominantly in Ch-fed diabetic rats, whereas IDL increased in the Ch and propylthiouracil-fed control rats. According to sodium dodecyl sulfate polyacrylamide gel electrophoresis, VLDL and IDL from Ch-fed diabetic rats were unusual in that they contained more apo E, A-I and A-IV. Concentrations of plasma apo A-I and apo E were measured by radioimmunoassay. The diabetic rats fed a labo chow showed a significantly lower concentration of plasma apo E than control rats. Plasma apo E was extremely higher in the diabetic rats fed a cholesterol diet. Plasma apo A-I was significantly increased in the diabetic rats fed a labo chow and those fed a cholesterol. Insulin treatment significantly decreased the concentrations of VLDL, IDL and LDL and plasma concentration and distribution of apolipoproteins in lipoprotein subfractions changed toward normal. However, decreased HDL in the Ch-fed diabetic rats was not recovered by insulin treatment.

Animals↗
PubMed1985

[Biventriculographic and clinicopathologic evaluation of apical hypertrophy: with reference to asymmetrical septal hypertrophy with hypertension].

To clarify the pathogenesis of apical hypertrophy with asymmetrical septal hypertrophy (ASH), left ventriculography in the right anterior oblique projection (LVG), biventriculography (BVG), and endomyocardial biopsy of the right ventricle were performed for patients with ASH. The patients were categorized in four groups according to ECG, LVG and BVG. Patients with hypertrophic cardiomyopathy (HCM) were divided into two subsets; (A) Apical hypertrophy group (AH: nine patients), with ECG showing left ventricular hypertrophy (LVH) and giant negative T waves (GNT), and with LV configurations showing the S or SR form at end-diastole on LVG. (B) Non-apical hypertrophy group (non-AH: 12 patients), with ECG showing LVH without GNT and LV configuration showing R form at end-diastole on LVG (cf: Fig. 1). Patients with ASH and hypertension (ASH-HT) were also divided into two subsets; (A) AH: seven patients. (B) non-AH: nine patients. Analysis of LVG and BVG: In HCM, the septal configuration showed the TS X S form in both two subset groups. The septal configuration in ASH-HT was divided into the NH form, which was clearly distinguishable from the septal configuration in HCM, and the TS X S form as in cases with HCM. In both HCM and ASH-HT, the diastolic thickness of the anterior apical wall was significantly thicker in all patients with AH than that in non AH. In HCM, the diastolic thickness of the septum and the percent systolic thickening did not significantly differ between AH and non-AH groups. In ASH-HT, the NH form showed similar diastolic thickness of the septum and % systolic thickening in AH and non-AH groups. On the other hand, the TS X S form in non-AH group showed greater thickness and lower % systolic thickening similar to those of HCM. Histological analysis of endomyocardial biopsy; In HCM, the transverse diameters of the myocytes and the biopsy scores did not differ significantly between AH and non-AH groups. In ASH-HT, the TS X S form in non-AH group had longer diameters and higher biopsy scores similar to those of HCM compared to the NH form in AH group. In conclusion, both HCM and ASH-HT may have apical hypertrophy manifested by giant negative T waves in the EKG and spade like form of left ventriculogram. In addition, apical hypertrophy in ASH-HT with the NH form of septal configuration seemed to be caused by hypertension.

Adult↗
PubMed1985

[Myocardial involvement in diabetic patients evaluated by exercise thallium-201 scintigraphy and cardiac catheterization].

To evaluate myocardial involvement in diabetes mellitus, we studied 39 patients with negative double-Master's test and without hypertension by exercise thallium-201 (T1-201) myocardial scintigraphy using a bicycle ergometer. Among the 39 patients, 12 (30.8%) showed filling defects in the scintigrams (positive cases), including eight with stress-induced defects and four with fixed defects. The positive cases had higher scores of diabetic complications (3.6 +/- 2.4 vs 2.1 +/- 1.8; p less than 0.05) and longer durations of diabetes as compared with those of the negative cases. The frequency of insulin therapy was also greater in the positive cases. Eleven patients (5 positive and 6 negative cases) who underwent cardiac catheterization had no significant stenotic lesions of their coronary arteries. However, all of the positive cases showed abnormal wall motion, mainly hypokinesis, by left ventriculography (LVG). The abnormalities of the LVG corresponded to the findings of the scintigrams (i.e. filling defects and decrease in washout ratios by circumferential profile analysis). These results suggest that in some diabetics myocardial involvement exists in the early stage without overt cardiac disease and exercise T1-201 scintigraphy is useful in detecting pre-clinical cardiomyopathy. Cardiomyopathy in diabetics seems to be due to disturbances of the myocardial microcirculation.

Adult↗
PubMed1984

[The role of prostaglandins for norepinephrine clearance in borderline hypertension].

Studies were done to determine the role of endogenous prostaglandins (PGs) for norepinephrine (NE) clearance in 10 male borderline hypertensives (BHT) (age: 20-28) and six age-matched male normotensives (NT). Two experimental protocols were followed in these subjects: 10 min orthostasis with blood sampling (protocol I), and 100 ng/kg/min of L-NE infusion for 60 min at supine position. Blood was collected from indwelling catheter at every min for 10 min after stopping the NE infusion (protocol II). Plasma NE was measured by THI method using HPLC. Disappearance curve of plasma NE was analyzed following the two compartment open model. The orthostasis and the steady state NE infusion were repeated after 150 mg/day of indomethacin (Ind) for three days. There were significant increases in plasma NE after orthostasis in both groups: from 180.8 +/- 28.0 pg/ml to 346.2 +/- 78.0 pg/ml (p less than 0.05) in NT and from 120.1 +/- 12.8 pg/ml to 289.6 +/- 20.3 pg/ml (p less than 0.001) in BHT, but there were no significant differences between the two groups. Ind pretreatment did not alter these responses. The calculated half-time of the first exponential phase (T 1/2) was 1.50 +/- 0.07 min in NT which decreased to 0.98 +/- 0.10 min (p less than 0.05) after Ind pretreatment. In BHT, T 1/2 was 1.03 +/- 0.08 min (p less than 0.01 vs NT), which was not significantly changed after Ind. These results may suggest that endogenous PGs have some role(s) in NT for NE clearance, probably exerting inhibitory action on neuronal uptake. In BHT, neuronal uptake of NE is increased, probably due to an adaptation mechanism to elevated blood pressure.

Adult↗