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Biomedical subjects

R Takeda

Publications and source records attributed to R Takeda.

At least 163 records · Page 9Linked to original sources
PubMed1992

Usefulness of ultrasonography and Doppler color flow imaging in the diagnosis of internal jugular phlebectasia.

A 20-year-old woman presented to our hospital for investigation of a left neck mass. Ultrasonographic examination of the jugular mass demonstrated an echo-free space, the caliber of which markedly increased when the patient shifted from the sitting to the recumbent position or performed a Valsalva maneuver. On color Doppler flow imaging, a slow flow signal flowing in the direction opposite to that of the common carotid artery was found within this space. Ultrasonography and color Doppler flow imaging thus proved to be useful for correctly diagnosing internal jugular phlebectasia.

Adult↗
PubMed1992

Clinicopathologic study of alcohol-like liver disease in non-alcoholics; non-alcoholic steatohepatitis and fibrosis.

Alcohol-like liver injury (ALLI) in non-alcoholics has not been elucidated in Japan. The present study attempted to characterize the clinicopathologic features of ALLI in routine liver biopsies. ALLI was found in 1% of 561 biopsy cases obtained from 1988 to May, 1991 at Kanazawa University Hospital. Laboratory data characteristically showed only a mild to moderate degree of dysfunction, and none of the cases exhibited jaundice. Hepatic histology showed a mild to moderate degree of perivenular, pericellular and/or portal stellate fibrosis with a varying degree of fatty change and inflammatory cell infiltration. Portal stellate fibrosis with a varying degree of cell infiltration was more severe than the centrilobular or pericellular fibrosis in all cases. Intralobular inflammatory cell infiltration was associated with spotty or single hepatocyte necrosis, but extensive hepatocyte necrosis was not observed. Neutrophil infiltration was absent or minimal, and lymphocytes predominated in all cases. Mallory bodies were rare and were found in a few hepatocytes of only one of the 7 cases. The above histologic findings in ALLI were very similar to those seen in liver disease in Japanese alcoholics, and were somewhat different from ALLI reported in Western countries. In cases in which hepatic fibrosis, characterized by pericellular, perivenular or portal stellate fibrosis dominated without apparent hepatic necrosis and inflammation, the term "non-alcoholic steatofibrosis" is more suitable to depict its liver histology, being very similar to the alcoholic fibrosis frequently seen in Japanese alcoholics.

Adult↗
PubMed1992

Esophageal clearance scintigraphy, in diabetic patients--a preliminary study.

The aim of this preliminary study was to evaluate the predictive value of esophageal clearance scintigraphy (ECS) in the diagnosis of esophageal autonomic neuropathy in diabetic patients without any esophageal symptoms. A single swallow ECS was performed in 12 diabetic patients and 15 normal volunteers, and esophageal transit time (ETT) and esophageal (Es) T 1/2 values were calculated. ETT and Es T 1/2 were found to be significantly prolonged in the diabetic group (p less than 0.01 and p less than 0.05, respectively). In this preliminary study, our results strongly suggest that ECS may be an important noninvasive diagnostic tool in the evaluation of diabetic patients with asymptomatic esophageal autonomic neuropathy.

Adult↗
PubMed1992

Determination of urinary 18-hydroxycortisol in the diagnosis of primary aldosteronism.

Urinary excretion of 18-hydroxycortisol (18-OHF), 18-hydroxycorticosterone (18-OHB) and aldosterone 18-glucuronide (Aldo-18-glu) was measured in 10 patients with primary aldosteronism; 5 with aldosterone-producing adenoma (APA) and 5 with idiopathic hyperaldosteronism (IHA), 10 patients with essential hypertension (EHT) and 11 normotensive subjects. In EHT patients, urinary 18-OHF (172 +/- 15 micrograms/24h) and 18-OHB (3.1 +/- 0.6 micrograms/24h) values were not significantly different from 18-OHF (142 +/- 35 micrograms/24h) and 18-OHB (3.6 +/- 0.5 micrograms/24h) in the controls. Urinary 18-OHF values were significantly higher in APA (640 +/- 213 micrograms/24h) when compared with controls and EHT, whereas 18-OHB (11.3 +/- 1.5 micrograms/24h) values were only slightly elevated. Both 18-OHF and 18-OHB were significantly increased in APA compared with 18-OHF (232 +/- 56 micrograms/24h) and 18-OHB (4.6 +/- 0.3 micrograms/24h) in IHA. The two urinary steroids, especially 18-OHF proved to be a useful marker for the diagnosis of APA, confirming the previous findings. Aldo-18-glu was not significantly different between APA and IHA. In normal subjects when sodium intake was restricted to 48meq/day for four days the urinary 18-OHF was increased two fold to 383 +/- 59 micrograms/24h (p less than 0.01 vs control period) associated with comparable rise in plasma renin activity. This suggests that the biosynthesis of 18-OHF is partly under control of renin-angiotensin axis in normal subjects.

18-Hydroxycorticosterone↗
PubMed1992

Effects of halothane on membrane potential and discharge activity in pairs of bulbar respiratory neurons of decerebrate cats.

In aiming to test the possibility of synaptic interactions, the effect of inhalation of halothane (2% for 90 sec) was studied on 45 out of 88 pairs of respiratory neurons, simultaneously recorded with intracellular and extracellular microelectrodes, in both sides of the ventral respiratory group of decerebrate cats. Halothane produced various effects on these respiratory neurons; namely, depolarization (n = 30) or hyperpolarization (n = 15) of intracellularly recorded neurons, an increase (n = 7) or decrease (n = 38) in the firing of extracellularly recorded neurons. However, with repeated application, the agent produced a consistent effect in a given cell. Spike-triggered averaging of synaptic noise, using spikes of non-antidromically-activated respiratory units, did not reveal any unitary postsynaptic potential but a symmetric synaptic wave of medium-frequency-oscillation (35-50 Hz) in 7 pairs. In addition, power spectral analysis of the membrane potential and spike-interval histogram of the paired neuron, displayed no correlated activity suggestive of synaptic interactions. For all the neuronal pairs examined, halothane produced random effects on their patterns of firing and synaptic waves. The present results suggest that halothane exerts a selective effect on each respiratory neuron and that the lack of a correlated response to application of halothane reflects the lack of synaptic interaction between pairs of bilaterally sampled neurons of the ventral respiratory group.

Action Potentials↗
PubMed1992

Enhanced cholesteryl ester transfer protein activities and abnormalities of high density lipoproteins in familial hypercholesterolemia.

Cholesteryl ester transfer protein may play a role in the cholesteryl ester metabolism between high density lipoproteins (HDL) and apolipoprotein B-containing lipoproteins. To investigate relationship between HDL and cholesteryl ester transfer protein (CETP) activity in the development of atherosclerosis, the present study has focused on CETP activity in the patients with familial hypercholesterolemia (GH). HDL-C and HDL-C/apo A-I mass ratio in heterozygous FH were lower than those in normolipidemic controls. There was a 2-fold increase in total CETP activity in incubated FH serum compared with normolipidemic controls. Assays for CETP activity in the lipoprotein deficient serum (d greater than 1.215 g/ml) were carried out by measuring the transfer of radioactive cholesteryl ester from HDL (1.125 less than d less than 1.21 g/ml) to LDL (1.019 less than d less than 1.060 g/ml). CETP activities in heterozygous FH (79 +/- 4 nmol/ml/h) was significantly higher than those in normolipidemic controls (54 +/- 6 nmol/ml/h). The increased total cholesteryl ester transfer mainly results from increased CETP activity in the d greater than 1.215 g/ml, possibly reflecting an increase in CETP mass in serum. Increased CETP activity in the d greater than 1.215 g/ml was correlated positively with IDL-cholesterol/triglyceride mass ratio (r = 0.496, p less than 0.01), and negatively with HDL-cholesterol/apo A-I mass ratio (r = -0.334, p less than 0.05). These results indicate that the enhanced CETP activities may contribute to increase risk for developing atherosclerosis in FH by changing the distribution of cholesteryl ester in serum lipoproteins.

Adult↗
PubMed1992

Long-term course and cardiac sympathetic nerve activity in patients with hypertrophic cardiomyopathy.

OBJECTIVE: To investigate the relation between regional myocardial sympathetic nerve activity and the electrocardiographic and cardiac functional changes in hypertrophic cardiomyopathy. DESIGN: A retrospective study to compare the findings of myocardial scintigraphy with iodine-123 metaiodobenzylguanidine (MIBG) and the serial electrocardiographic changes. SETTING: Myocardial scintigraphy was performed with iodine-123 MIBG and thallium-201 and single photon emission computed tomography (SPECT) in the division of nuclear medicine of Kanazawa University Hospital. Both SPECT studies were performed within a week. PATIENTS: 22 patients with hypertrophic cardiomyopathy classified according to their serial electrocardiographic changes--namely, 15 patients with an increase in or the appearance of a negative T wave (group A) and seven patients with a conduction disturbance or a decrease in or disappearance of the negative T wave (group B). The mean follow up period was 45 (range 12-143) months. RESULTS: Group B showed a high rate of decreased activity or defects in MIBG uptake compared with group A (p less than 0.005). The areas of decreased activity or defects corresponded with the hypertrophied portion of the left ventricular wall. Although the early myocardial uptake (MIBG: thallium ratio) was similar in both groups, the mean (SD) MIBG clearance rate was significantly higher (p less than 0.05) in group B (0.25 (0.17)) than in group A (0.10 (0.15)). CONCLUSION: Abnormalities of regional myocardial sympathetic nerve activity may be important in patients with hypertrophic cardiomyopathy and suspected progression of myocardial damage.

3-Iodobenzylguanidine↗
PubMed1992

Evidence that glycine and GABA mediate postsynaptic inhibition of bulbar respiratory neurons in the cat.

Experiments were carried out on decerebrate cats to identify transsynaptic mediators of spontaneous postsynaptic inhibition of bulbar inspiratory and postinspiratory neurons. Somatic membrane potentials were recorded through the central micropipette of a coaxial multibarreled electrode. Blockers of type A gamma-aminobutyric acid (GABA-A) and glycine receptors were iontophoresed extracellularly from peripheral micropipettes surrounding the central pipette. Effective antagonism was demonstrated by iontophoresis of agonists with antagonists; application of strychnine antagonized the action of glycine but not GABA, and application of bicuculline antagonized the action of GABA but not glycine. In both types of neurons, iontophoresis of either antagonist depolarized the somatic membrane and increased input resistance throughout the respiratory cycle. Bicuculline preferentially depolarized the somatic membrane in both types of neurons during inactive phases. Strychnine increased the firing rate of inspiratory neurons during inspiration despite maintenance of somatic membrane potential at preiontophoresis levels. Tetrodotoxin reduced the effects of iontophoresed bicuculline and strychnine, suggesting that the action of the antagonists required presynaptic axonal conduction. The present results suggest that presynaptic release of both GABA and glycine contributes to tonic postsynaptic inhibition of bulbar respiratory neurons. GABA-A receptors appear to contribute to inhibition during inactive phases in inspiratory and postinspiratory neurons, whereas glycinergic mechanisms appear to contribute to inspiratory inhibition in inspiratory neurons.

Action Potentials↗
PubMed1992

Effect of sodium restriction on urinary excretion of 19-noraldosterone and 18,19-dihydroxycorticosterone, newly identified mineralocorticoids in man.

19-Noraldosterone, which was recently shown to be synthesized and produced in the human adrenal gland, possesses potent mineralocorticoid activity. 18,19-Dihydroxycorticosterone [18,19-(OH)2B], a possible precursor of 19-noraldosterone, has also been identified in human urine. To elucidate the regulatory mechanism for these newly described steroids, we studied the effect of sodium restriction on the urinary excretion of 19-noraldosterone and 18,19-(OH)2B in six normal subjects. 18,19-(OH)2B and 19-noraldosterone were measured by specific RIAs after purification of the urine extract by high performance liquid chromatography. The 24-h urinary excretion of 19-noraldosterone and 18,19-(OH)2B during the control period were 107 +/- 40 (+/- SE) pmol/day and 5.6 +/- 0.8 nmol/day, respectively. After sodium restriction, the values increased approximately 2-fold (P less than 0.05), to 259 +/- 76 pmol/day and 15.6 +/- 4.5 nmol/day, respectively. Virtually identical responses were seen for aldosterone (from 21 +/- 6.0 to 38 +/- 10 nmol/day), 18-hydroxycorticosterone (from 9.9 +/- 1.1 to 21 +/- 2.8 nmol/day), and 18-hydroxycortisol (from 377 +/- 93 to 554 +/- 129 nmol/day). These observations suggest that 19-noraldosterone and 18,19-(OH)2B are partly under the control of the renin-angiotensin system in normal subjects.

18-Hydroxycorticosterone↗
PubMed1992

Histopathological factors related to diastolic function in myocardial hypertrophy.

To clarify the histopathologic influence on diastolic function in the hypertrophied heart, we compared the echocardiographic and histopathologic findings in 9 controls, 10 patients with hypertrophic cardiomyopathy (HCM), and 8 hypertensive patients with asymmetric septal hypertrophy (HT-ASH). M-mode echocardiography was used to determine the left ventricular diastolic function. Mean diameter of myocytes, percentage of fibrosis and disarrangement were quantitatively calculated from right ventricular endomyocardial biopsy specimens. In both HT-ASH and HCM, the isovolumic relaxation time was significantly longer and the rapid filling volume tended to be smaller than in the controls. Histopathologically, the mean diameter of myocytes and percentage of myocardial interstitial fibrosis did not differ significantly between HT-ASH and HCM. However, quantitative disarrangement of myocytes in HCM was significantly greater than that in HT-ASH. Multiple regression analysis showed that the percentage of fibrosis was the most significant factor related to diastolic left ventricular dysfunction in HT-ASH, while disarrangement of myocytes was the most significant in HCM. We conclude that diastolic dysfunction in HT-ASH can be attributed to the percentage of fibrosis, and to disarrangement of myocytes in HCM.

Adult↗
PubMed1992

Altered secretion of corticosteroids and prolactin in adrenal regeneration hypertensive rats.

To assess the possible role of mineralocorticoids in the onset and maintenance of hypertension in adrenal regeneration hypertensive (ARH) rats, the change in plasma mineralocorticoids, with adrenal regeneration after enucleation in ARH rats was investigated and compared with those in unilaterally nephroadrenalectomized, 1% saline-fed (UNA) rats, sham-operated, 1% saline-fed (1% NaCl) rats and water-fed (water) rats. Plasma aldosterone was determined by RIA and the other mineralocorticoids were measured by HPLC. How plasma PRL, a marker of central dopaminergic activity, affected aldosterone secretion was determined by RIA. In ARH, plasma corticosterone (B), 18-OH-DOC and aldosterone levels 2 weeks after operation were as low as 20-30% of corresponding values, but the plasma DOC level was almost 100% of the corresponding value in the other groups. Four weeks after operation plasma B increased to a level comparable with that in the other groups and the plasma aldosterone level remained low. However, plasma DOC and 18-OH-DOC levels 4 weeks after operation were as high as 120-200% of corresponding values in the other groups. Six weeks after operation, the plasma aldosterone level returned to a value comparable with that in UNA and 1% NaCl and plasma DOC and 18-OH-DOC levels returned to corresponding values in the other groups. The plasma PRL level 4 weeks after operation was significantly lower in ARH than in the other groups. These results suggest that transient DOC and 18-OH-DOC increases observed in ARH may be important in the onset of hypertension, while other factors may be involved in its maintenance and that the transient central dopaminergic hyperactivity observed in ARH may be responsible for a delayed return from aldosterone deficiency.

Adrenal Glands↗
PubMed1992

Twenty-four year spironolactone therapy in an aged patient with aldosterone-producing adenoma.

A case of primary aldosteronism treated with spironolactone therapy has been followed up for 24 years. This is probably the longest case of spironolactone therapy for primary aldosteronism that has ever been reported. Long-term treatment with spironolactone controlled the hypertension and prevented hypokalemic alkalosis in this patient, without any deleterious effects on steroid biosynthesis. Based on data obtained during dose reduction and subsequent withdrawal of spironolactone, it is suggested that the suppressed plasma renin activity associated with adenoma-induced aldosteronism develops prior to hypokalemia and hypertension.

Adenoma↗
PubMed1992

Urinary excretion of 19-noraldosterone, 18, 19-dihydroxycorticosterone and 18-hydroxy-19-norcorticosterone in patients with aldosterone-producing adenoma or idiopathic hyperaldosteronism.

Urinary excretion of 19-noraldosterone, 18. 19-dihydroxycorticosterone (18, 19(OH)2-B), 18-hydroxy-19-norcorticosterone (18-OH-19-nor-B), 18-hydroxycorticosterone (18-OH-B), 18-hydroxycortisol (18-OH-F) and aldosterone were measured in 25 patients with primary aldosteronism, 16 with an aldosterone-producing adenoma and 9 with idiopathic hyperaldosteronism. In patients with idiopathic hyperaldosteronism, urinary 19-noraldosterone (207 +/- 51 pmol/day), 18, 19(OH)2-B (21 +/- 4.2 nmol/day) and 18-OH-19-nor-B (879 +/- 213 pmol/day) levels were lower but not significantly different from 19-noraldosterone (263 +/- 56 pmol/day), 18, 19(OH)2-B (40 +/- 8.7 nmol/day) and 18-OH-19-nor-B (1322 +/- 267 pmol/day) seen in patients with aldosterone-producing adenoma. Urinary aldosterone did not differ significantly between patients with idiopathic hyperaldosteronism and those with aldosterone-producing adenoma. Both urinary 18-OH-B and 18-OH-F excretion were significantly higher in aldosterone-producing adenoma (39 +/- 5.2 nmol/day, 1660 +/- 318 nmol/day, respectively) compared with patients with idiopathic hyperaldosteronism (19 +/- 3.3 nmol/day, 541 +/- 93 nmol/day, respectively) (p less than 0.05). Though urinary 18-OH-F and 18-OH-B concentrations were useful markers, the mineralocorticoid steroids which we can only now measure, 19-noraldosterone, 18, 19(OH)2-B and 18-OH-19-nor-B, could not be used to distinguish the two subsets of primary aldosteronism.

18-Hydroxycorticosterone↗
PubMed1992

Disproportionate hypertrophy of the interventricular septum and its regression in Cushing's syndrome. Report of three cases.

Three patients of Cushing's syndrome with severe disproportionate hypertrophy of the interventricular septum are reported. All three underwent adrenalectomy and the diagnosis of Cushing's syndrome was confirmed by the presence of adrenal adenoma. All three showed hypertension before the adrenalectomy and two remained hypertensive following adrenalectomy. Before the operations the electrocardiograms revealed inverted T waves in broad leads, and mechanocardiogram systolic and diastolic dysfunction. After the adrenalectomies, abnormal findings on electrocardiograms were normalized and septal hypertrophy was completely regressed. It appears that not only high aortic pressure but also excessive plasma cortisol may be an etiologic factor of the left ventricular hypertrophy in Cushing's syndrome.

Adrenalectomy↗
PubMed1992

Hereditary angioedema complicated with chronic renal failure: report of sibling cases.

Hereditary angioedema (HAE) is known as a deficiency state of C1 inhibitor (C1 INH), an important protease inhibitor protein involved in the complement system. As with other components of the classical pathway of the complement system, a state of its deficiency often causes clinical immunoregulatory disorders. A 45-yr-old brother and a 63-yr-old sister with HAE both developed chronic renal failure, probably due to chronic glomerulonephritis, and required regular hemodialysis. This is, to our knowledge, the first report of sibling cases of HAE associated with chronic renal failure.

Angioedema↗
PubMed1992

[Guanidino compounds in the elderly].

To examine the metabolism of guanidino compounds in the elderly, we measured the serum concentrations of urea nitrogen, creatinine (Cr), guanidinoacetic acid (GAA) and creatine (CR) in middle-aged and elderly subjects. We also measured muscle mass in the elderly. The elderly subjects tended to have lower serum GAA concentrations than middle-aged subjects. On the contrary, CR concentrations of elderly subjects were higher than those of middle-aged subjects. Bedridden elderly subjects tended to have lower serum GAA concentrations and lighter muscle mass than ambulatory elderly subjects. On the contrary, serum CR concentrations of bedridden subjects were higher than those of ambulatory subjects. CR is an essential substance for muscle energy metabolism. These results indicate that high serum CR concentrations due to low CR metabolism in skeletal muscle might suppress glycine amidinotransferase (GAT) activity, resulting in decreased GAA production in the elderly.

Aged↗
PubMed1992

[Left atrial booster pump function in patients with hypertrophic cardiomyopathy and essential hypertension: evaluations based on left atrial pressure-volume relationship].

In patients with hypertrophic cardiomyopathy (HCM) and essential hypertension (HT), left ventricular dysfunction in early diastole which is associated with left atrial contraction plays an important role in left ventricular filling. To evaluate left atrial booster pump function, we analyzed left atrial preload (left atrial pressure at the end of diastasis; LAPd, left atrial volume index at the end of diastasis; LAVd), left atrial afterload (left ventricular end-diastolic pressure; LVEDP, left ventricular chamber stiffness constant; K), and left atrial ejection indices (left atrial ejection fraction during atrial contraction; LAEF, left atrial ejection volume index during atrial contraction; ACVI). The study subjects consisted of control subjects (n = 5), HT patients (n = 6), and HCM patients (n = 11). The left ventricular wall was significantly thicker in the HT and HCM groups. The left ventricular rapid filling volume index was less in the HT group, and significantly less in the HCM than in the control group. LAPd and LAVd were greater in the HT group than in the control group, and greater in the HCM group than in the HT group. LVEDP and K were greater in the HT group than in the control group, and significantly greater in the HCM group than in the other 2 groups. ACVI was greater in the HT group than in the control group, but in the HCM group, ACVI was significantly less than in the HT group and did not differ significantly from that in the control group. LAEF was significantly less in the HCM group than in the other 2 groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗