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Biomedical subjects

M Asai

Publications and source records attributed to M Asai.

At least 253 records · Page 14Linked to original sources
PubMed1985

Relationship between maternal prolactin levels during pregnancy and lactation in women with pituitary adenoma.

To evaluate the relationship between maternal prolactin (PRL) levels and post puerperal lactation, serum PRL levels in patients with pituitary adenoma were serially measured throughout pregnancy. The patients were divided into two groups. In patients in group 1 with complete resection of the adenoma by transsphenoidal surgery, the serum PRL level did not show a sharp rise with the onset of pregnancy as can be seen in normal pregnancy, but continued at low levels of 30ng/ml or lower until the term. In patients in group 2 who had successful pregnancies following incomplete resection of pituitary adenoma in combination with bromocriptine or bromocriptine therapy alone, high PRL levels were maintained from early in gestation until term. One out of 3 patients in group 1 showed good lactation despite low PRL levels during pregnancy. Conversely, in 22 patients in group 2 with high PRL levels during pregnancy, there were 3 patients with insufficient lactation. After suckling stimuli, the maternal PRL level did not rise in either group. These results suggest that the PRL level in maternal blood during pregnancy might not influence the amount of lactation in puerperium. In addition, an abnormally high or low PRL level during pregnancy did not affect the PRL level in cord blood or amniotic fluid or the growth of neonates.

Adenoma↗
PubMed1985

Binding capacity of sex-hormone-binding globulin and free testosterone determination in evaluation of hirsute women.

To investigate the relation between free testosterone (T) and binding capacity of sex-hormone-binding globulin (SHBG-BC) and a degree of hirsutism, 34 women were classified into 3 groups according to the criteria of Ferriman and Gallway on the degree of the hirsutism; 11 patients with a total score of 1 to 3 (group 1), 8 patients with a total score of 4 to 10 (group 2), and 15 patients with a total score of 11 or more (group 3). Total plasma T, SHBG-BC, and free plasma T were measured in each group, and they were compared with those of controls. In groups 1 and 2, mean levels of total T were slightly higher than in controls but the differences were not significant. Total T levels were extremely elevated in group 3. Mean level of SHBG-BC in group 1 was slightly lower than in controls but was not statistically significant. SHBG-BC was drastically reduced in groups 2 and 3. The percent free T levels and free T concentrations were significantly higher than those of controls in groups 2 and 3, but not in group 1. The results suggested that decreased SHBG-BC and increased free T might be the cause of hirsutism in women with normal total T levels.

Amenorrhea↗
PubMed1985

[Changes in % free testosterone and sex-hormone binding globulin during danazol administration].

To clarify the androgen balance on the administration of danazol a study was conducted on the levels of % free testosterone (% free T) and sex-hormone-binding globulin (SHBG) during the therapy and the binding properties of danazol to SHBG and androgen receptor. It was found that danazol displaced testosterone (T) from SHBG and R1881 from androgen receptor, in vitro. During treatment with danazol, levels of % free T were increased about three fold, but in contrast the SHBG concentration were significantly decreased. Similar changes in % free T were observed by computer simulation. These data suggest that the androgenic effects of danazol were the results of increased free T levels by the T-displacing ability of danazol from SHBG. The concentration of SHBG might be reduced as a consequence of increased levels of free T. On the other hand, danazol binding to androgen receptor might partially inhibit the action of excess amounts of free T, because the androgenization during therapy was too weak to compare the levels of free T.

Computers↗
PubMed1984

A colorimetric assay for plasma antithrombin III using a new synthetic peptide substrate (PS-915).

A colorimetric assay for plasma antithrombin III (ATIII) has been developed, using a new synthetic peptide substrate, PS-915 (H-D-Phe-Pro-Arg-CHA). PS-915 is freely water-soluble and its aqueous solution is stable. It is highly specific for thrombin and its Km value is about the same as that of S-2238. By enzyme hydrolysis, the new substrate liberates 3-carboxy-4-hydroxyaniline (CHA), which turns blue in color due to the complex formation with added alkaline-pentacyanoammine ferroate. The assay is a three-stage kinetic, one-point procedure, based on the method of antithrombin (heparin cofactor activity) determination. Since absorption measurements of the CHA are usually obtained at 700 nm, no blank correction is necessary even when hyperbilirubinemic, lipemic and/or hemolyzed plasma are used. The calibration curve for ATIII is linear over the range of 0-175% of normal and has a high degree of reproducibility. The results obtained by this method are well correlated with data obtained by the commonly used chromogenic assay or by radial immunodiffusion.

Adult↗
PubMed1984

Pentylenetetrazol kindling produces a long-lasting elevation of IR-Met-enkephalin but not IR-Leu-enkephalin in rat brain.

Pentylenetetrazol (PTZ) kindling was induced in male Wistar rats by daily i.p. injections of 40 mg/kg of the convulsant agent. IR-Met-enkephalin and IR-Leu-enkephalin were quantified in several brain regions 16 days after the last stimulus. In addition other rats received another PTZ dose on the sixteenth day and the samples were analyzed 1 and 24 h later. The results showed a long-lasting elevation in amygdala, septum, hypothalamus and hippocampus of IR-Met-enkephalin only. These brain structures also showed a decrease of IR-Met-enkephalin 1 h after the PTZ-induced seizure, but reached newly elevated levels 24 h later. IR-Leu-enkephalin levels only showed a decrease in striatum 1 h after PTZ-induced convulsions. The data suggest that Met-enkephalin is related to permanent changes in brain function induced by PTZ kindling, while Leu-enkephalin may depend on the occurrence of epileptic seizures.

Amygdala↗
PubMed1984

Depression and ventricular enlargement.

Compared with controls, 46 depressed patients showed increased ventricular-brain ratio (VBR). Patients with poor outcome, single episode, onset at 50 years or over, or without melancholia were found to have greater VBR than controls.

Adult↗
PubMed1984

Effects of prolyl hydroxylase inhibition on arterial collagen synthesis and blood pressure in hypertensive rats.

Changes in arterial collagen synthesis and the effects of P-1894B, a potent inhibitor of prolyl hydroxylase, were investigated on rat hypertension, induced by deoxycorticosterone acetate (DOCA) and salt. In DOCA-salt hypertensive rats, prolyl hydroxylase activity increased significantly in the abdominal aorta and in the mesenteric artery. Incorporation of 14C-proline into the thoracic aorta, abdominal aorta and mesenteric artery was higher and the hydroxyproline content of the abdominal aorta and mesenteric artery was higher than in the control rats. Treatment with P-1894B significantly inhibited prolyl hydroxylase activity, reduced arterial collagen synthesis, but did not prevent or reverse hypertension.

Animals↗
PubMed1984

[Noninvasive studies of dynamic left ventricular outflow obstruction in patients with sigmoid septum].

In order to evaluate the clinical significance of the markedly protruding interventricular septum into the left ventricular (LV) cavity (sigmoid septum), we performed non-invasive studies including amyl nitrite (AN) inhalation in 21 patients (pts) with two-dimensional echocardiographic (2DE) documentations. LV outflow tract (LVOT) obstruction was determined by the presence at least three of the following findings at rest or during AN inhalation: 1) a loud apical ejection systolic murmur (ESM), 2) a midsystolic dip in the carotid pulse, 3) systolic anterior motion (SAM) of the mitral valve (MV) or chordae tendineae, and 4) systolic semiclosure of the aortic valve (AV). The 21 pts were subdivided into six pts (group I) with resting (two pts) or provocative (four) obstruction, and 15 pts (group II) without obstruction. Their ages ranged from 40 to 85 years with an average of 65. No pt had evidence of hypertrophic cardiomyopathy. Results were as follows: In five pts of group I a long ESM with a mid-systolic peak was recorded near the apex. After AN inhalation, this murmur was markedly intensified. On the contrary, all pts of group II had a short and early systolic murmur, which was not markedly intensified by AN. In contrast to group II, group I pts had a significantly smaller LV end-diastolic dimension, a smaller LVOT dimension, higher percent thickening of the LV posterior wall, higher fractional shortening and decreased aorto septal angle (the angle between the anterior aortic wall and the interventricular septum by 2DE). On 2DE, each pt of group I showed significant narrowing between the protruded septum and the hypercontractile LV posterior wall with the papillary muscle. Anteriorly shifted chordae tendineae noted as the SAM on the M-mode echocardiogram might also play an important role on the genesis of obstruction. The signs of LVOT obstruction at rest disappeared following oral administration of propranolol in two pts of group I. These observations suggested that LVOT obstruction might occur in some pts with sigmoid septum and the hypercontractile state, and that a systolic murmur observed in this condition should be differentiated from a functional murmur in the aged or a systolic murmur in hypertrophic obstructive cardiomyopathy.

Adult↗
PubMed1984

[Mechanism of an early diastolic posterior motion of the interventricular septum in patients with mitral stenosis: with special reference to left ventricular inflow velocity pattern].

The mechanism of an early diastolic posterior motion of the interventricular septum (IVS) was investigated by means of M-mode, two-dimensional and pulsed Doppler echocardiographies in 53 patients with pure mitral stenosis (MS). Velocity patterns of the blood flow at the inflow tract of the left ventricle (LVIT) were classified into three types as previously reported (cf. Fig.3). The results obtained were as follows: The mitral valve orifice area (MVA) was significantly smaller in patients with type III of the LVIT flow velocity pattern than in patients with type I (p less than 0.001). An amplitude ("a") of the posterior IVS motion in systole (P1) was significantly diminished in type III (4.2 +/- 1.1 mm) than in type I (6.6 +/- 1.5 mm) (p less than 0.001). An amplitude ("b") of the posterior IVS motion in early diastole (P3) showed a significant increase in type III (7.5 +/- 1.2 mm) than in type I (5.2 +/- 1.5 mm) (p less than 0.001). Difference of the amplitude between P1 and P3 ("a-b") was significantly greater in type III (-3.4 +/- 1.1 mm) than in type I (1.4 +/- 0.9 mm) (p less than 0.0001). MVA was correlated statistically with "a" (r = 0.58, p less than 0.001), "b" (r = -0.38, p less than 0.01) and "a-b" (r = 0.80, p less than 0.0001). Deformity of the left ventricular cavity due to the flattened IVS in early diastole was observed in severe MS with an augmented septal P3 dip. A case of severe MS with type III velocity pattern and an augmented P3 dip showed type II velocity pattern and a decreased P3 dip after the attack of acute myocardial infarction. These findings suggested a close relationship between type III of the LVIT flow velocity pattern and the prominent septal P3 dip. The importance of diastolic suction of the left ventricle in producing an early diastolic posterior motion of IVS (P3) was discussed.

Biomechanical Phenomena↗
PubMed1984

[Left ventricular function in patients with right ventricular overload evaluated by exercise echocardiography: comparison of pulmonary hypertension and atrial septal defects].

To evaluate left ventricular function in patients (pts) with right ventricular overload, exercise echocardiographic studies using a bicycle ergometer were performed for seven pts with pulmonary hypertension (PH), two with cor pulmonale (CP) and 16 with atrial septal defects (ASD), and the results were compared with those of 10 (control I) and 27 (control II) normal persons. These subjects were categorized in two study groups; study I consisting of PH, CP and control group I with an exercise workload of 25 watts for 3 min; and study II consisting of ASD and control group II with an exercise workload of 50 watts for 3 min. The results were as follows: M-mode echocardiography revealed that: During exercise, the stroke volume (SV) was increased with a significant decrease of left ventricular end-systolic dimension (LVDs), but without a change in left ventricular end-diastolic dimension (LVDd) in control groups I and II, with a marked increase of LVDd and a slight decrease of LVDs in the ASD group. By contrast, the SV in the PH group tended to decrease during exercise with a slight decrease of LVDd, but without a significant change in LVDs. Right ventricular dimension (RVD) was significantly increased during exercise in the PH group, but was decreased in the ASD group. In control groups I and II, RVD did not change during exercise. In ASD, and control groups I and II, the peak velocity of circumferential fiber shortening (Vcf) was increased during exercise, and the peak negative Vcf was significantly decreased. However, these parameters exhibited impaired responses during exercise in the PH group. Abnormal interventricular septal (IVS) motion at rest tended to become normal during exercise in 12 of 16 pts with ASD. In all pts with PH, however, IVS motion did not change substantially during exercise. There were similar parameter responses between the PH and CP groups. Two-dimensional echocardiography showed that: The left ventricular short-axis view demonstrated a diastolic left ventricular configuration which changed from oblique to relatively circular orientation during exercise in the ASD group. In four of five pts with PH, the diastolic configuration of the left ventricle was oblique because of a loss of the normal curvature of the IVS at rest and during exercise. The diastolic left ventricular configuration improved during exercise in only one pt with PH, with slightly elevated pulmonary arterial systolic pressure as in the ASD group.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1984

[M-mode echocardiographic standardization of interventricular septal motion and its clinical significance].

Systolic and diastolic motions of the interventricular septum (IVS), especially of its lower portion at the level of the chordae tendineae, were evaluated by M-mode echocardiography in normal subjects and in patients with various cardiac disorders. The following conclusions were derived from this study. In normal subjects, downward motion of the IVS exhibited three patterns; namely, P1, between the onset of electrical depolarization and the onset of the second heart sound; P2, between the onset of the second heart sound and the E point of the anterior mitral leaflet; and P3, between the E point of the anterior mitral leaflet and the end of the left ventricular rapid filling phase, during each cardiac cycle. The systolic IVS pattern (P1) of atrial septal defect was classified as follows: Normal type: nearly normal posterior motion during ventricular systole, Flat type: flat motion during ventricular systole, Paradoxical (early systolic) type: anterior motion during the first half of ventricular systole, followed by normal posterior motion, Paradoxical (pansystolic) type: anterior motion during ventricular systole. In atrial septal defect, the right ventricular dimension was markedly increased in the flat and paradoxical (pansystolic) types compared with those of the normal and paradoxical (early systolic) types. Marked downward IVS motion (P2) was observed in cor pulmonale with paradoxical pulse, pulmonary hypertension, Ebstein's anomaly, pulmonic insufficiency, atrial septal defect, funnel chest, tricuspid insufficiency and constrictive pericarditis. In cor pulmonale with paradoxical pulse, the deep downward motion (P2) was observed more distinctly during inspiration compared to expiration, and right ventricular inflow velocity pattern was characterized by an apparent increase in peak flow in velocity of the diastolic rapid filling wave during inspiration. Two interesting findings were a deep "y" trough of the jugular pulse tracing and prominent P2 in funnel chest. Therefore, it was likely that exaggerated P2 seemed to be direct evidence of a marked increase in right ventricular rapid filling in the presence of normal or decreased left ventricular rapid filling. The augmented septal dip of P3 was observed in cases with the third heart sound as in normal subjects, and those with mitral insufficiency, and ventricular septal defect, constrictive pericarditis and mitral stenosis. We theorized that exaggerated P3 results from the "sucking action" secondary to increased left ventricular rapid filling velocity in cases with the third heart sound or constrictive pericarditis.(ABSTRACT TRUNCATED AT 400 WORDS)

Diastole↗