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Biomedical subjects

R Takeda

Publications and source records attributed to R Takeda.

At least 469 records · Page 26Linked to original sources

Clinical evaluation of biventriculo-cineangiographic findings in hypertensive left ventricular hypertrophy.

In the present study, we demonstrated that hypertensive left ventricular hypertrophy can be divided angiographically into symmetrical (SH) and asymmetrical septal hypertrophy (ASH) groups. In the SH group, the dynamics of the septal wall and the free wall were almost the same as those of the control group. On the other hand, the ASH group rather resembled the HCM group in the thickness and dynamics of the septal wall and the free wall as well as in the septal configuration. The most characteristic difference of the ASH and HCM groups from the SH group was in the significantly greater thickness of the septal wall at end diastole. However, in view of the developmental mechanism of hypertensive heart, it is interesting to note that the more the septal-free wall ratio increases, the more the thickness of the septal wall increases in the SH group.

Adult↗

Effects of acetaldehyde on the membrane potential and membrane resistance of the identified neurons in the abdominal ganglion of Aplysia kurodai.

Actions of acetaldehyde on membrane potentials and membrane resistances of Aplysia neurons were studied using an intracellular recording and current injection technique. Several functionally different neurons in the abdominal ganglion of A. kurodai were identified on the basis of their morphological and electrophysiological characteristics. Application of between 5 and 50 mM acetaldehyde produced depolarization of the membrane, in all types of cells investigated. This depolarization was accompanied by an increase in the rate of spike discharge. The amplitude and the rates of rise and fall of the action potential were reduced and the duration of the spike was prolonged. Acetaldehyde had no significant effect on the input resistances of ganglion cells. These actions of the aldehyde were observed to be similar in the completely isolated neuron-soma preparation separated from the neighbouring cells or synapses.

Acetaldehyde↗

Effects of acetaldehyde on the membrane resistance in the smooth muscle of the guinea-pig taenia caecum.

The action of acetaldehyde on the membrane resistance of the guinea-pig taenia caecum was investigated with a double sucrose-gap method in different ionic environments. Application of acetaldehyde (10--20 mM) produced hyperpolarization, block of spike discharge and reduction of the membrane resistance. The reduction of the membrane resistance by acetaldehyde was potentiated by increasing the external K+ concentration and by replacement of Cl- with NO3-; it was reduced by lowering the external K+ concentration and by replacement of Cl- with benzenesulfonate. Replacement of NaCl with Tris-Cl, sucrose, or LiCl had no appreciable effect on the action of acetaldehyde on the membrane resistance. It therefore seemed likely that acetaldehyde increased the membrane conductance for K+ and Cl- more than for Na+. Although this action of acetaldehyde was similar to the alpha-action of catecholamine, the decrease of the membrane resistance and hyperpolarization induced by acetaldehyde remained unchanged in the presence of phentolamine.

Acetaldehyde↗

A case of Ménétrier's disease accompanied by severe hypogammaglobulinemia.

We describe a case of Ménétrier's disease accompanied by severe hypoproteinemia with marked decrease of gamma globulin. Roetogenograms and endoscopic findings of the upper gastrointestinal tract demonstrated enlarged gastric rugae and multiple small protuberances of the duodenal mucosa. Histological findings a gastric biopsy specimens showed mucosal thickening and hypertrophy. Plasminogen activator activities were increased in both gastric and jenunal mucosal biopsy specimens. Severe hypoproteinemia was proven by the Gordon test and by determination of protein content of gastric juice to be due to protein loss into the gastric lumen.

Adult↗

[The high pressure liquid chromatography of corticoids. II. Analysis of synthetic corticoids in blood and urine (author's transl)].

The high pressure liquid chromatographic (HPLC) technique was developed to separate and quantitate the synthetic corticosteroids (s-CS) which are widely used clinically. 1) 12 kinds of s-CS in alcoholic solvent and 2) some of their metabolites in the plasma and urine of healthy subjects with oral administration of s-CS were investigated for the preliminary work. The results are summarized as follows: 1) Cortisol sodium phosphate, Dexamethasone 21, disodium phosphate, Paramethasone acetate, Cortisol acetate, Cortisone acetate, Methylprednisolone acetate, Prednisone, Dexamethasone, 9 alpha-fluorocortisol, Betamethasone, Triamcinolone, and Prednisolone in ethanol were clearly separated by HPLC from Cortisol (F). In the suitable condition of the HPLC (LC-2 type) with a Zorbax SIL column, organic solvent (cyclohexane:dichloromethane:ethanol = 9:4:1)-carrier mobile phases and UV detector, the retention time of each s-CS was obviously different from that of F. The calibration curve was obtained in a linear line with regards to each s-CS. The mean recovery was 97.6% and the coefficient of variation were 1.6 (intraassay) and 7.2 (interassay)%. The sensitivity of the steroid determination was 200pg order. 2) The serial changes in plasma concentrations of s-CS; CS-metabolites and endogenous F were shown in 3 healthy males and 2 females following oral administration of the s-CS. The separated metabolites in number and quality depended on the kind of s-CS. Prednisone and other kinds of the acidified products were separated from prednisolone in the plasma and urinary samples of the healthy subjects as well as Addisonian patients. In conclusion, the HPLC method is useful for the separation and quantitation of the UV-absorbing CS of human plasma and urine. The obtained chromatograms may be an indication of the metabolic state of the subject with treatment of s-CS.

Adrenal Cortex Hormones↗

The effects of streptozotocin diabetes on hepatic triglyceride lipase activity in the rat.

The function of the hepatic triglyceride lipase (H-TGL) is not yet clear. The purpose of the present study was to investigate the possible hormonal regulation of H-TGL. Postheparin plasma was obtained 3 min after the intravenous injection of 50 U/250 g body weight of heparin into male Wistar rats. The lipase activities were measured using substrate containing [14C] triolein emulsified with gum arabic and were expressed in mumoles of free fatty acid released/ml/hour (mean +/- SD). H-TGL was the lipase activity remaining after inhibition of lipoprotein lipase (LPL) by 1.0 M NaCl. Diabetic rats were prepared by intravenous injection of streptozotocin (STZ), 65 mg/kg body weight. The contributions of H-TGL and LPL to the total plasma triacylglycerol hydrolase (TGH) activity depend on the amount of heparin injected and the time of blood withdrawal after heparin injection. H-TGL was maximally released at higher heparin (50 U/250 g body weight) concentrations, compared to LPL which was maximally released at lower heparin (5 U/250 g body weight) concentrations. H-TGL was significantly higher at 3 min after the injection of 50 U of heparin/250 g body weight than at 20 min. Twenty-four-hour fasting produced a significant fall in H-TGL compared to H-TGL in fed rats. Total TGH was significantly lower in diabetic rats 3 days after STZ injection. In diabetic rats 3, 5, and 7 days after STZ injection, H-TGL were significantly lower than those in control rats. H-TGL and H-TGL/total TGH were 9.49 +/- 0.99 and 0.551 +/- 0.071, respectively, in rats 3 days after STZ injection, compared to H-TGL (13.46 +/- 0.69) and H-TGL/total TGH (0.739 +/- 0.052) in control nondiabetic rats. When diabetic rats were treated with insulin, total TGH (14.37 +/- 3.01) and H-TGL (6.77 +/- 4.12) rose to 25.16 +/- 1.02 (total TGH) and 16.49 +/- 1.13 (H-TGL), that were comparable to activities in control nondiabetic rats. Separation of H-TGL and LPL was performed using heparin-Sepharose affinity chromatography of postheparin plasma. The enzyme activity of peak I from STZ rats, which is eluted by 0.72 M NaCl-Veronal buffer, pH 7.4 and corresponds to H-TGL, was approximately half the activity from control rats. TGH released by heparin from isolated rat liver parenchymal cells was investigated. The enzyme activites released from isolated liver parenchymal cells prepared from STZ rats was approximately half that from control rats. The role of insulin in the regulation of LPL has been well documented. Our findings suggest that H-TGL also is under hormonal regulation by insulin in rats.

Animals↗

A unique affinity and adaptation of renomedullary interstitial cells for hypertonic medium.

Collagenase-dispersed cells of renal papillary tissue from adult mongrel dogs were directly inoculated in a modified M.E.M. (Eagle's) giving an osmolality of approximately 1,000 mOsm/L by addition of urea and sodium chloride, and were cultured in an atmosphere of 95% air-5%CO2 at 37 degrees C. Within twelve hours after inoculation, spindle-shaped cells attached firmly to the surface of culture dishes, while the other cellular components of the inner medulla remained floating in the medium. After several days in culture, the colonies grew to form a confluent cell layer, which was composed of almost homogenous cells giving spindle-shape. These cells kept on the major characteristics of renomedullary interstitial cell (RIC) in morphology as well as in function to produce prostaglandin E. These results appear to be principally attributable to the unique characteristics of RIC, one of which is affinity for high osmolality and the other is different behavior in attachment to the dish. As the procedure proposed here was relatively simple and did not require a long period up to the development of monolayer, it would provide a promising model "in vitro" to study the humoral regulation of prostaglandin production.

Animals↗

Prolapsing right atrial myxoma.

Echocardiography was of great value in establishing the correct diagnosis in a patient with symptoms of congestive heart failure due to a prolapsing right atrial myxoma. The movement of the tumor into the right ventricle through the atrioventricular orifice during diastole was identified by the echocardiogram and confirmed by angiography and direct observations during surgery. The indicator dilution curve also showed abnormal hemodynamic features simulating tricuspid incompetence, in relation to the movement of the tumor.

Coronary Angiography↗