Search PubMed⌕ Search

Biomedical subjects

T Omae

Publications and source records attributed to T Omae.

At least 217 records · Page 12Linked to original sources

Worsening of anemia induced by long-term use of captopril in hemodialysis patients.

During long-term captopril administration to hypertensive patients on maintenance hemodialysis, a decrease in hemoglobin, hematocrit, and red blood cell count was observed in 9 out of 12 cases. The maximum decrease in hemoglobin, on the average, was detected after 10.9 months of captopril treatment, when the average decrease was 20.5%. The average daily dose of the drug was 27.6 mg/day throughout the observation period. Mean corpuscular constants, reticulocyte count, serum iron, and total iron-binding capacity did not change significantly. Coombs' test was negative. Neither serum total protein nor body weight changed significantly. Fever, skin rashes, leukopenia, and eosinophilia were not observed. There was no significant correlation between the degree of decrease in hematological indices and the dose of captopril. After discontinuation of captopril administration, anemia improved to pretreatment levels. In 2 of the 3 patients who did not show worsening of anemia, an anabolic steroid was administered in association with captopril. It is suggested that captopril should be used with caution in hemodialysis patients.

Adult↗

Autologous immune complex nephritis in streptozotocin-induced diabetic rats.

In order to investigate the influence of diabetes mellitus on immune complex-mediated nephritis , we produced Heymann nephritis in streptozotocin-induced diabetic rats (DM-HN group) in which the clinical course for 24 weeks and histological changes were examined. Nondiabetic rats with Heymann nephritis (HN group) and diabetic rats (DM group) were also examined as controls. The degree of proteinuria, hypoproteinemia, hyperlipidemia and anemia were more pronounced and the mortality rate was higher in the DM-HN group than in the HN group or in the DM group. Histologically, larger and more subepithelial or intramembranous electron-dense deposits as well as a more markedly thickened glomerular basement membrane (GBM) were observed in the DM-HN group than in the HN group. In conclusion, the nephrotic manifestations and histological changes in the GBM in Heymann nephritis were augmented by the association with diabetes mellitus.

Animals↗

Autoregulation of cerebral blood flow in young and aged spontaneously hypertensive rats (SHR).

Autoregulation of cerebral blood flow (CBF) to the controlled hemorrhagic hypotension was studied in young adult spontaneously hypertensive rats (SHR, 3.4 months of age) and aged SHR (20.3 months). There were no differences in average values for mean arterial pressure and baseline CBF between two groups of rats. During hypotension, however, CBF was more reduced in aged SHR than in young SHR, indicating that the lower limit of cerebral autoregulation is shifted to a higher level in aged SHR. Such upward shift of the autoregulation is likely due to a long-lasting hypertension which may lead to the diminished vasodilatory response of the brain to hypotension.

Aging↗

The renin-angiotensin-aldosterone system and circadian rhythm of urine variables in normotensive and hypertensive subjects.

Forty-two middle-age male subjects, aged from 47 to 54 years old, were divided into three groups; 14 normotensives (NT), 16 borderline hypertensives (BHT) and 12 hypertensives (HT). The environmental effects were neutralized as much as possible by keeping their activities synchronized and their plasma and urine variables simultaneously investigated using the same protocol as under normal physiologic conditions. The circadian rhythms of urinary excretions of Na, K, Cl, creatinine, aldosterone, adrenaline and noradrenaline were analyzed by a multivariate method (cosinor method). Both systolic and diastolic blood pressure were statistically significantly different among the three groups and body weight was greater in HT than in NT. Other plasma and urine variables examined, however, were not significantly different among the three groups. A statistically significant circadian rhythm was detected in the urine variables. The rhythm characteristics, such as the mesor, amplitude and acrophase, of the urine variables except for the acrophase of urinary Na excretion were not significantly different among the three groups; the circadian acrophase of urinary Na in HT and BHT appeared significantly earlier than in NT. The pathophysiological and clinical significance of the earlier appearance of the circadian acrophase of urinary Na in hypertensive subjects still remains a unique characteristic requiring further investigation.

Aldosterone↗

A possible role of hypokalemia in the manifestation of high QRS voltage and sinus bradycardia in patients with primary aldosteronism.

We analyzed electrocardiograms obtained from 29 Japanese patients with primary aldosteronism (PA) and in 106 patients with essential hypertension (EHT). QRS voltage was higher (p less than 0.05) and heart rate was slower (p less than 0.01) in cases of PA. A significant reduction in QRS voltage and a significant increase in heart rate were observed after short-term potassium replacement or after short-term administration of spironolactone, preoperatively, and within 2 to 4 weeks after the removal of aldosteronoma. These significant changes in QRS voltage and heart rate were always accompanied by significant increases in the serum potassium concentration but not always by a reduction in blood pressure. The long-term follow-up of EHT-patients showed a slower reduction in their high QRS voltage, despite effective antihypertensive therapy. Thus, hypokalemia, in addition to hypertension, may be relevant to the high QRS voltage in PA. There also appeared to be a relationship between hypokalemia and bradycardia.

Adult↗

Pulmonary hemorrhage in experimental cerebral ischemia in mongolian gerbils. Brain metabolism and lung pathology.

Pulmonary changes in acute cerebral ischemia were studied in anesthetized Mongolian gerbils, in which both carotid arteries were occluded simultaneously. Lactate, pyruvate and adenosine triphosphate (ATP) in the brain were measured as indicators of the severity of cerebral ischemia. Microscopic changes in the lung were arbitrarily scored from 0 (normal) to 3 points (severely affected) by the grade and the extent of lesions. Mean arterial pressure (MAP) was also measured through the cannulated femoral artery before and after carotid artery occlusion in a separate group of animals. Cerebral lactate was increased while ATP decreased in ischemic animals in which pulmonary changes such as intra-alveolar hemorrhages were prominent and frequent. The lung pathology score averaged 1.3 in animals with severe ischemia (lactate greater than or equal to 10 mM/Kg), 0.7 in moderate ischemia (5-10 mM/Kg) and 0.3 in mild or no ischemia (less than 5 mM/Kg), respectively, suggesting that severe brain ischemia may cause fulminant pulmonary changes. The mechanism of pulmonary lesions in acute cerebral ischemia is discussed.

Adenosine Triphosphate↗

Catecholamines, angiotensin II and sodium concentrations in cerebrospinal fluid in young men with borderline hypertension.

To evaluate the role of central nervous mechanisms and their relationships to the peripheral sympathetic nervous system in borderline hypertension, we measured catecholamines, angiotensin II (AII) and sodium (Na) concentrations in cerebrospinal fluid (CSF) with plasma catecholamines concomitantly in 12 young men with borderline hypertension and 7 age-matched healthy normotensive men on ordinary salt intake. Plasma norepinephrine (NE) and epinephrine (E) were higher in the borderline hypertensives than in the normotensives (NE: 239 +/- 15 vs 190 +/- 11 pg/ml, p less than 0.05, E: 83 +/- 9 vs 43 +/- 6 pg/ml, p less than 0.01). NE levels in CSF were also higher in the borderline hypertensives than in the normotensives (200 +/- 15 vs 150 +/- 18 pg/ml, p less than 0.05). In most of the subjects, CSF E and plasma and CSF dopamine levels were below the sensitivity of the assay. CSF NE correlated positively with both plasma NE (p less than 0.01) and mean blood pressure (p less than 0.05) in all subjects. Immunoreactive AII and Na concentrations in CSF did not differ between the borderline hypertensives and normotensives. These results suggest that peripheral sympathoadrenal overactivity in young subjects with borderline hypertension may be related to an altered function of central noradrenergic neurons. AII and Na in the central nervous system do not appear to have an important role in borderline hypertension.

Adolescent↗

Arrhythmia during insulin-induced hypoglycemia in a diabetic patient.

The temporal relationship between the level of blood glucose and the frequency of ventricular premature contractions (VPCs) during 24 hours was examined in a 45-year-old man with diabetes mellitus who was treated with a regular insulin injection. The number of VPCs increased sharply when the blood glucose level fell to about 50 mg/dL while the patient was awake. There was a minimal increase in VPCs during sleep, despite a decrease to 21 mg/dL in the blood glucose level. The insulin tolerance test produced frequent VPCs during hypoglycemia, which was suppressed by glucose administration. Changes in the level of plasma epinephrine correlated well with changes in the frequency of VPCs. These data suggest that increased levels of plasma epinephrine may have played a role in the genesis of VPCs that occurred during insulin-induced hypoglycemia.

Arrhythmias, Cardiac↗

Necrotizing vascular lesions in spontaneously hypertensive rats with nephrotic syndrome: hypercoagulability as a contributory factor.

Heymann nephritis was induced in rats with spontaneous hypertension (group HN), and renal lesions were investigated at the twentieth and thirty-sixth week. An identical group given antihypertensive drugs (group HN-AH), an identical group given anticoagulant drugs (group HN-AC), and a nonimmunized control group of spontaneously hypertensive rats (controls) were also examined. Massive proteinuria, hypoalbuminemia, and hyperlipidemia were present in groups with induced Heymann nephritis (HN, HN-AH, and HN-AC). Coagulation studies demonstrated a shortening of prothrombin time, an increase in serum fibrinogen and thrombocytes, and a reduction of antithrombin III in the groups HN and HN-AH. Necrotizing lesions were observed only in group HN and without further elevation in blood pressure. Intravascular thrombosis was prominent at the twentieth week, and marked fibrinoid necrosis appeared at the thirty-sixth week. These vascular lesions were not observed in the HN-AH, HN-AC, and control groups. Thus, a state of hypercoagulability in addition to high blood pressure probably contributes to the genesis of necrotizing vascular lesions in spontaneously hypertensive rats with nephritis.

Animals↗

[Central pontine and extrapontine myelinolysis following rapid correction of hyponatremia--report of an autopsy case].

A case of central pontine myelinolysis (CPM) following rapid correction of hyponatremia was reported and literatures were reviewed. The case was 61-year-old nonalcoholic female who had taken an operation of craniopharyngioma 23 years ago. Fifteen years later, she received re-operation for the recurrent tumor, followed by replacement therapy of corticosteroid and clofibrate. She was otherwise well until two weeks before entry, when she noticed abrupt onset of high grade fever, nausea, vomiting and general malaise. She was admitted to an emergency hospital because of weakness, disorientation and a slight impairment of consciousness, but she was able to speak and to take some food per os. Laboratory studies disclosed urinary tract infection and showed a serum sodium level of 117 mEq/l, potassium 2.9 mEq/l, a serum osmolarity 232 mO sm/l and urine osmolarity 141 mEq/l. She was diagnosed to have an exacerbation of adrenal insufficiency with hyponatremia and hypotonic dehydration triggered by urinary tract infection. Intravenous administration of vitamin B complex, electrolytes including KCL, 5% glucose solution and physiological saline with a large amount of corticosteroid was performed aggressively. Serum sodium concentration was raised to 161 mEq/l in two days, and the increased level had been maintained more than five days, resulting in coma and flaccid quadriplegia. During this period, there was no episode of hypotension, hypoglycemia, hypoxia nor hepatic failure which could have caused brain damage.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Insufficiency↗

[Protective effects of 4-(o-benzylphenoxy)-N-methylbutylamine hydrochloride (bifemelane) on acutely induced cerebral ischemia in Mongolian gerbils and spontaneously hypertensive rats (SHR)].

Effects of new antihypoxic agent (bifemelane) on survival and brain metabolism were studied in acute cerebral ischemia induced by bilateral carotid artery ligation in mongolian gerbils and SHR. Either 10 mg/kg or 30 mg/kg body weight of bifemelane solved in distilled water was intraperitoneally administered 1 hr in gerbils and 1.5 hrs in SHR prior to carotid ligation, and same amount of vehicle was also given in similar manner for control animals. Brain tissue metabolites such as lactate, pyruvate and ATP were determined by using the enzymatic technique in the ischemic brain frozen in situ 1 hr after carotid ligations in SHR. Mean survival times following carotid ligations were 186 +/- 255 min (+/- SD) in control gerbils, 429 +/- 455 min in those with 10 mg/kg of bifemelane, and 310 +/- 429 min in those with 30 mg/kg respectively, its difference between control and 10 mg/kg group being significant (P less than 0.05). Supratentorial lactate concentrations in the ischemic brains of SHR were substantially the same among the groups, whereas ATP levels were 0.62 +/- 0.24 mM/kg in control animals, 1.10 +/- 0.67 mM/kg in rats with 10 mg/kg of the drug, and 1.13 +/- 0.42 mM/kg in those with 30 mg/kg, respectively. In animals with a high dose pretreatment, the reduction of ATP was significantly smaller than that in control (P less than 0.02), indicating that this agent prevents a decline of high energy phosphate in the ischemic brain although anaerobic metabolites increase similarly in animals of all experiment groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Clinical importance of reversibility in primary goitrous hypothyroidism.

Twenty seven hypothyroid patients with a serum concentration of thyroid stimulating hormone (TSH) of over 40 mU/1 were followed up for three to 20 weeks without replacement therapy. The serum thyroid hormone concentrations increased with a dramatic decrease in serum TSH values in 14 patients (reversible group) but there was no significant change in the other 13 (irreversible group). Fourteen out of 19 patients with goitre but none of the eight patients without goitre belonged to the reversible group. All of the 11 patients with a high uptake of iodide by the thyroid, three of the six with a normal uptake, and none of the 10 with a low uptake belonged to the reversible group. These observations indicate that patients with goitrous hypothyroidism with a preserved thyroid uptake of iodide are likely to become euthyroid spontaneously without replacement therapy.

Adult↗