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Biomedical subjects

T Takeda

Publications and source records attributed to T Takeda.

At least 1,063 records · Page 59Linked to original sources

Variable neurohumoral and hemodynamic responses to exercise in patients with exertional angina: influence of the severity of coronary artery disease.

To assess neurohumoral and hemodynamic responses to exercise in patients with exertional angina, we measured plasma norepinephrine (NE) concentrations in 23 patients with exertional angina (with no heart failure) and compared the results with their coronary arteriographic findings. The 23 patients were divided into two groups: 14 cases with multiple vessel disease (MVD) and 9 cases with one-vessel disease. At resting state there were no significant differences between the two groups in levels of NE. At maximal exercise there were no significant differences between the groups in increases of heart rate, blood pressure, and rate-pressure product, but exercise-induced increase of plasma NE (%) was significantly larger in MVD (131.6 +/- 95.4%) (mean +/- SD) than in one-vessel disease (69.0 +/- 45.3%) (p less than 0.01). In conclusion, plasma NE responses to exercise differ between patients with multiple vessel disease and patients with one-vessel disease.

Angina Pectoris↗

Clinical significance of U1-RNP immune complexes in mixed connective tissue disease and systemic lupus erythematosus.

We measured U1-RNP: anti-U1-RNP immune complexes (U1-RNP ICs) in patients with mixed connective tissue disease (MCTD) and systemic lupus erythematosus (SLE) to examine the clinical significance of circulating U1-RNP ICs. The level of U1-RNP ICs in 11 patients with MCTD was significantly higher than that in 22 normal subjects and there was a close correlation between the level of U1-RNP ICs and the clinical disease activity index of MCTD. In contrast, the level of U1-RNP ICs in 31 patients with SLE was not significantly higher than that in normal subjects and that was not correlated with the clinical disease activity index of SLE or the renal histologic activity index of lupus nephritis. We conclude that U1-RNP ICs are present in sera of patients with MCTD and SLE, and that the level of U1-RNP ICs may be closely associated with clinical disease activity in patients with MCTD.

Adult↗

Alterations in myocardial systolic and diastolic function in patients with active systemic lupus erythematosus.

Echocardiographic studies were performed to evaluate myocardial function in active patients with systemic lupus erythematosus (SLE). Fourteen patients were studied in the active stage before corticosteroid therapy (active SLE); 10 of them were reexamined after therapy (inactive SLE). Computer-assisted analysis of digitized echoes of the left ventricular dimension was performed. The peak rate of change in dimension during systole (-dD/dt) was reduced in active SLE compared with normal control subjects (2.57 +/- 0.15 cm/sec vs 3.37 +/- 0.14 cm/sec, p less than 0.01). The peak rate of change in dimension during diastole (+dD/dt) was also reduced in active SLE compared with normal control subjects (3.16 +/- 0.19 cm/sec vs 4.41 +/- 0.20 cm/sec, p less than 0.01). After therapy, -dD/dt in inactive SLE was improved compared with active SLE (from 2.56 +/- 0.20 cm/sec to 3.13 +/- 0.19 cm/sec, p less than 0.001). Positive dD/dt in inactive SLE was also improved compared with active SLE (from 3.29 +/- 0.22 cm/sec to 4.23 +/- 0.23 cm/sec, p less than 0.01). No significant differences were found between inactive SLE and normal control subjects as to -dD/dt and +dD/dt. Significant correlations were found between anti-DNA antibody titers and both -dD/dt and +dD/dt (r = -0.97 p less than 0.0001, and r = -0.71 p less than 0.05, respectively). These results suggest that active SLE patients have left ventricular dysfunction that may be caused by an immunopathologic mechanism in SLE.

Adolescent↗

Circulating atrial natriuretic polypeptide in essential hypertension.

To investigate the significance of atrial natriuretic polypeptide (ANP) in essential hypertension, we measured plasma ANP concentrations in 43 subjects with essential hypertension uncomplicated by cardiac or renal failure, in 16 subjects with borderline hypertension, and in 17 normotensive control subjects. Plasma ANP levels were significantly higher in hypertensive subjects compared to borderline hypertensive subjects (p less than 0.05) and normotensive control subjects (p less than 0.05). Hypertensive subjects with left ventricular hypertrophy (LVH) had higher plasma ANP levels than the hypertensive group as a whole (p less than 0.05). A significant positive correlation was observed between mean blood pressure and plasma ANP level in the hypertensive group (n = 43, gamma = 0.77, p less than 0.01). Furthermore, plasma ANP level was decreased significantly after 4 weeks of effective antihypertensive therapy compared with the initial value (p less than 0.05). These results suggest that plasma ANP is frequently elevated in hypertensive subjects with markedly high blood pressure or LVH, and it can be reduced by effective therapy with antihypertensive drugs.

Adult↗

Circulating atrial natriuretic peptides in hyperthyroidism and hypothyroidism.

Plasma concentrations of atrial natriuretic peptides were measured in 32 normal control subjects, 25 patients with hyperthyroidism, and 18 patients with hypothyroidism. Atrial natriuretic peptide values were measured before and after successful therapy with methimazole or 1-thyroxine. Plasma atrial natriuretic peptide concentration was increased in patients with hyperthyroidism (48.0 +/- 19.5 pg/ml) but was decreased in patients with severe hypothyroidism (16.3 +/- 5.7 pg/ml) compared with values in normal control subjects (31.2 +/- 9.5 pg/ml). There was no significant difference between values in normal control subjects and mildly hypothyroid patients (35.0 +/- 12.2 pg/ml). The plasma atrial natriuretic peptide concentration was correlated with the serum thyroxine level and heart rate. The elevated atrial natriuretic peptide concentration in hyperthyroidism decreased, whereas the reduced atrial natriuretic peptide concentration in severe hypothyroidism increased, compared with the initial value after successful therapy. These results suggest that plasma atrial natriuretic peptide concentration is frequently increased in hyperthyroidism and is frequently decreased in severe hypothyroidism, and that thyroid hormone is one of the regulatory factors for circulating atrial natriuretic peptides.

Adult↗

Use of sucrose during removal of cryoprotectants after thawing eight-cell mouse embryos.

Eight-cell mouse embryos were frozen in 0.5-ml plastic straws in modified Dulbecco's phosphate buffered saline (PBS) plus 5% steer serum plus either 1.32 M dimethyl sulfoxide (DMSO) or 1.32 M glycerol. Upon thawing, embryos were diluted 1:4 with 0.0, 0.2, 0.6, or 1.0 M sucrose solutions within the straws. Thawing was either in air at ambient temperature or in 8 degrees C or 38 degrees C water. After 48 h of culture, more embryos frozen in DMSO and thawed in 8 degrees C and 37 degrees C water developed to blastocysts (87 and 93%, respectively) than embryos thawed in air (75%; P<0.05). No significant differences in development were noted among the three thawing regimens when embryos were frozen with glycerol. There was no significant effect of concentration of sucrose during dilution on development of embryos postthaw. With glycerol as the cryoprotectant, damage to zonae pellucidae increased as thawing rates increased, whereas the opposite was observed with DMSO as the cryoprotectant (P<0.05).

Journal Article↗

Analysis and in vivo disruption of the gene coding for calmodulin in Schizosaccharomyces pombe.

Calmodulin is a low molecular weight calcium-binding protein that modulates many enzyme systems in eukaryotes. We have cloned the gene encoding calmodulin from the fission yeast, Schizosaccharomyces pombe, by using synthetic oligonucleotide probes that correspond to three distinct regions of Tetrahymena calmodulin. A 1.6-kilobase (kb) DNA fragment that hybridized to all of them contains a gene whose deduced product possesses 74% amino acid homology with bovine calmodulin. This gene, which is unique in the S. pombe genome and is named cam1, encodes 149 amino acids excluding the first methionine and is transcribed into mRNA of 1.2-kb length. It has an intron that apparently starts immediately after the initiation codon and is 126 bp long. S. pombe calmodulin exhibits more homology to vertebrate calmodulin than to that of the budding yeast, Saccharomyces cerevisiae. Gene disruption experiments revealed that cam1 gene function is essential for vegetative growth of S. pombe. Spores bearing disrupted cam1 halt growth soon after germination and rarely carry out the first cell division, indicating that calmodulin does not exist in excess in those cells.

Amino Acid Sequence↗

Expression of epithelial markers in sarcomatoid carcinoma: an immunohistochemical study.

Thirty-four cases of sarcomatoid carcinoma with minimal epithelial components (SC) and six cases of sarcomatous tumour without any epithelial component (ST) in various organs were studied by the immunoperoxidase technique for the expression of epithelial markers, cytokeratins and epithelial membrane antigen (EMA). Employing antibodies against both high and low molecular weight cytokeratins, sarcomatoid components in 30 examples of SC were stained positively. Epithelial membrane antigen was demonstrated in 19 out of 34 SC. The positive cells for epithelial markers within sarcomatoid components in some cases of SC, which were regarded as originating from squamous cell carcinoma, tended to be seen less frequently than in the tumours derived from adenocarcinoma or transitional cell carcinoma. In six cases of ST, stain for EMA was negative and stain for cytokeratins was positive in three examples. The immunohistochemical examination of epithelial markers in the tumours of these types may be of value in differentiating these tumours from true sarcomas.

Adenocarcinoma↗

Involvement of sympathetic nervous system inhibition in the hypotensive effect of bromocriptine in spontaneously hypertensive rats.

The hypotensive effect of bromocriptine in young (6 week old) spontaneously hypertensive rats (SHR) was studied. Blood pressure and plasma norepinephrine level in bromocriptine-treated SHR were significantly lower than those in vehicle-treated SHR after 3 weeks of treatment (5 mg/kg per day, i.p.), while no significant decrease of blood pressure or plasma norepinephrine level was observed after 2 weeks of treatment. These results suggest the involvement of sympathetic nervous system inhibition in the hypotensive effect of bromocriptine in SHR.

Aging↗

Enterotoxicity of El Tor-like hemolysin of non-O1 Vibrio cholerae.

The enterotoxicity of an El Tor-like hemolysin purified from non-O1 Vibrio cholerae was investigated. Fluid accumulation was induced by injection of purified hemolysin into the ligated intestinal loops in adult rabbits (De test), intraintestinal administration in infant rabbits (Dutta test), and oral inoculation in suckling mice. The accumulated fluid was invariably mucous and bloody, and a histological change in the mucosa was observed. These results suggest that the hemolysin is an enterotoxic factor that is responsible for non-O1 V. cholerae gastroenteritis.

Animals↗

Analysis of cell proteins in lymphoblasts of acute lymphocytic leukemia by two-dimensional gel electrophoresis.

The two-dimensional gel electrophoresis (2-DE) method developed by O'Farrell was used to analyze the differences of major proteins between lymphoblasts from children with acute lymphocytic leukemia (ALL) at diagnosis (lymphoblasts, n = 6), normal lymphocytes (n = 6) and lymphocytes from children with ALL in complete remission (lymphocytes in CR, n = 12). Among all the spots, those which were deeply stained and large were termed 'major spots'. Their number was 118. Two spots (No. B1 and B2) were characteristic of lymphoblasts, three spots (No. N1-N3) were characteristic of normal lymphocytes. In lymphocytes in CR, the latter spots were not always detected, and furthermore, the former spots were detected in several gels. These findings may relate to the insufficient recovery of functions of lymphocytes in CR. Several spots (No. 6, 55 and 57) in lymphoblasts were remarkably larger than those in normal lymphocytes. Spot No. 67, an actin spot, in lymphoblasts was smaller than that in normal lymphocytes. Spots No. 6, 55 and 57 in lymphocytes in CR were relatively small in size.

Adolescent↗

Central alpha 2-adrenergic stimulation increases neurointermediate lobe immunoreactive beta-endorphin in spontaneously hypertensive rats.

A possible influence of the central alpha 2-adrenergic system on beta-endorphin was examined in rat anterior pituitary, neurointermediate lobe, and plasma. The concentration of beta-endorphin in anterior pituitary, neurointermediate lobe, and plasma was determined by radioimmunoassay 15 minutes after subcutaneous injection of clonidine in 14-week-old spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). Clonidine reduced the concentration of the plasma beta-endorphinlike immunoreactivity in SHR and to a lesser extent in WKY. No significant changes in the concentration of beta-endorphinlike immunoreactivity were observed in anterior pituitary. Clonidine increased the concentration of neurointermediate lobe beta-endorphinlike immunoreactivity in SHR in a dose-related manner but did not affect the concentration in WKY. Administration of yohimbine (1 mg/kg) completely blocked the clonidine-induced increase of neurointermediate lobe beta-endorphinlike immunoreactivity in SHR, while prazosin (1 mg/kg) had no effect. These data suggest that the central alpha 2-adrenergic activation increases the neurointermediate lobe concentration of beta-endorphinlike immunoreactivity in SHR by suppressing beta-endorphin release from the neurointermediate lobe into the circulation.

Animals↗

Cardiac function of patients with essential hypertension during exercise and isoproterenol infusion.

The left ventricular function of patients with essential hypertension was examined during exercise and isoproterenol (ISP) infusion echocardiography. Twenty-eight hypertensive patients without cardiac hypertrophy (Group NH), 20 patients with cardiac hypertrophy (Group HH), 7 patients with cardiac dilatation (Group D), and 13 normotensives (Group N), were studied during multistage exercise using a supine bicycle ergometer. In addition, 23 hypertensives (Group NH: 13 patients, Group HH: 10 patients) and 10 normotensives were studied during ISP infusion (0.005 microgram/kg/min, and 0.01 microgram/kg/min, respectively, for 5 min). To assess the left ventricular function, an M-mode echocardiogram was utilized at rest and during exercise and ISP infusion. At rest, the isovolumic relaxation time (IRT) of each hypertensive group was significantly longer than that of Group N. IRT of Group HH and Group D was significantly longer than that of Group NH. Only the shortening fraction (SF) of Group D was significantly smaller than that of Group N. During exercise the SF increased in all groups, and only the SF of Group D was significantly smaller than that of Group N at a load of 75 W as well as at rest. The SF of Group HH tended to be smaller. There was no significant difference in peak negative dD/dt (-dD/dt) between any of the groups at rest; however, the -dD/dt of Group HH was significantly smaller than that of Group N during ISP infusion. We concluded that left ventricular diastolic function was disturbed in each hypertensive group at rest. Diastolic dysfunction worsened in Group HH and Group D. Only the left ventricular systolic function of Group D was already depressed at rest. Furthermore, unmanifested systolic dysfunction of the left ventricle seemed to be present in Group HH, because SF during exercise tended to be smaller and -dD/dt during ISP infusion was significantly smaller than that of Group N.

Adult↗

Prediction of PaO2 during treadmill walking in patients with COPD.

We studied the possibility of predicting PaO2 during exercise of a given oxygen uptake (VO2) from resting pulmonary function tests (PFTs) in patients with chronic obstructive pulmonary disease (COPD). The three-minute incremental treadmill exercise was performed with serial measurements of PaO2 via intra-arterial catheter in 46 patients (mean FEV1 = 1.09 +/- 0.49L, mean FEV1/FVC = 44 +/- 15 percent). In most of the patients, the changes of PaO2 were quite linear in relation to the oxygen uptake, so a slope (PaO2/VO2) could be obtained from the regression equation in each patient. The mean value of the slope (SL) was -23.0 +/- 16.6 mm Hg/L VO2/min. Correlation between SL and all parameters of resting PFTs were computed. Because of the high correlation coefficient between SL and %DCO (SL = -59.3 + 0.501 X %DCO, r = 0.851, p less than 0.001), it was possible to predict PaO2 at a given VO2 using the following equation: PaO2 predicted = PaO2 rest + SL X (VO2 -0.25), where SL was derived from measured %DCO and resting VO2 was assumed 0.25 L/min. There was a high correlation between the predicted PaO2 at VO2 of 1.0 L/min and the estimated PaO2 obtained from individual PaO2 regression with an r value = 0.898 and SEE = +/- 5.8 mm Hg. A prospective study in 12 patients with COPD was then carried out. There was a high correlation (r = 0.857) between the predicted PaO2 obtained from the present equation and the estimated PaO2 at VO2 = 1.0 L/min. It was concluded that PaO2 during treadmill walking with a given oxygen uptake is predictable from a resting PaO2 and a diffusing capacity. This predicted value may be useful in the management of patients with COPD.

Aged↗