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Biomedical subjects

M Mikami

Publications and source records attributed to M Mikami.

At least 91 records · Page 5Linked to original sources
PubMed1992

Human uterine endometrial adenocarcinoma: characteristic acquirement of synthetic potentials for II3SO3-LacCer and ganglio series sulfoglycosphingolipids after transfer of the cancer cells to culture.

The acidic glycosphingolipid composition of human uterine endometrial adenocarcinoma was compared with those of normal uterine endometrium at the proliferative and the secretory phases. Upon chemical composition analysis, no significant transformation-associated change of these glycolipids was observed. However, when cancer cells from the patients with human uterine endometrial adenocarcinoma were transferred to culture, the composition of glycosphingolipids, particularly sulfoglycosphingolipids, was significantly altered after the 70th doubling time. I3SO3-GalCer, which was contained in the original tissues of uterine endometrial adenocarcinomas, disappeared completely from the cultured cells at the 70th doubling time, whereas II3SO3-LacCer and ganglio series sulfoglycosphingolipids, which were originally contained in a trace amount or not present at all in the cancer tissues, became the major components in the total acidic glycosphingolipids in the cultured cells. Also, among cell lines established from several gynecological cancers, which include uterine cervical squamous carcinoma, uterine endometrial adenocarcinoma, ovarian clear cell carcinoma, choriocarcinoma, uterine sarcoma, ovarian sarcoma, and vulvar melanoma, only those cells derived from uterine endometrial adenocarcinoma expressed II3SO3-LacCer and ganglio series sulfoglycosphingolipids and the synthetic activities of these sulfoglycolipids, indicating that uterine endometrial adenocarcinoma cells characteristically lose the sulfotransferase to GalCer and acquire the sulfotransferase to LacCer after being transferred to culture in vitro. Thus, the unique sulfoglycosphingolipids and sulfotransferase are useful markers for the characterization of uterine endometrial adenocarcinoma among human gynecological cancers.

Adenocarcinoma↗
PubMed1992

Effects of gentamicin on catecholamine levels in the striatum, hypothalamus, adrenal gland and vas deferens.

The effects of gentamicin, an aminoglycoside antibiotic, on changes in the catecholamine levels in the rat striatum, hypothalamus, adrenal medulla and vas deferens were studied. When rats were i.v. injected with gentamicin (1.0 mg/kg), the catecholamine content of all tissues increased 2-4 h after injection. The increases in catecholamine levels induced by gentamicin were about 1.4- to 2.3-fold those induced by saline. The effect of gentamicin was observed at 0.1 or 0.5 mg/kg, and was maximal at 2.0 mg/kg. The activity of tyrosine hydroxylase, a rate-limiting enzyme in catecholamine biosynthesis, was markedly increased in all four tissues of rats treated with gentamicin (1.0 mg/kg, 4 h). However, direct addition of gentamicin to the tyrosine hydroxylase assay medium did not affect tyrosine hydroxylase activity. These data indicate that gentamicin administration to rats increases the catecholamine content of both central and peripheral catecholamine-containing tissues. The results also suggest that the effect of gentamicin is due to an indirect activation of tyrosine hydroxylase.

Adrenal Medulla↗
PubMed1992

Small cell colonies appear in the primary culture of adult rat hepatocytes in the presence of nicotinamide and epidermal growth factor.

Colonies of small hepatocytes appeared after the culture of primary adult rat hepatocytes for 4 days in serum-free modified Dulbecco's modified Eagle's medium containing 10 mmol/L nicotinamide and 10 ng/ml epidermal growth factor. Each colony consisted of cells that had a single nucleus and a higher nucleus/cytoplasm ratio than surrounding hepatocytes, and immunocytochemically these cells were stained with albumin and transferrin. Ultrastructurally these cells had mitochondria, peroxisomes and desmosomes, indicating that they were derived from hepatocytes. When 6 x 10(5) cells were plated on 35-mm dishes, about 5.5 colonies/mm2 were observed. This result suggested that about 1.5% of adult rat hepatocytes has the potential for multiple replications and of forming a focal colony. These cell populations had higher proliferative activities than surrounding hepatocytes. DNA synthetic activity could not be inhibited by 2% dimethyl sulfoxide. Flow cytometric analysis showed that both 2N and 4N nuclei synthesized their DNA until day 4 but that the number of 2N nuclei rapidly increased at day 5. This result correlated with the observation of the appearance of small cell populations indicating that the cells of these focal colonies were predominantly diploid.

Animals↗
PubMed1992

[Continuous monitoring of coronary venous oxygen saturation during PTCA and its relation to electrocardiographic ST changes].

The purpose of this study was to investigate change in coronary venous oxygen saturation (CSO2-Sat) during percutaneous transluminal coronary angioplasty (PTCA) and to compare the results with those of standard 12-lead ECGs (s-ECG) and epicardial ECG induced using an intracoronary guidewire (ic-ECG). CSO2-Sat was measured continuously in 10 patients undergoing PTCA; 5 patients with lesions in the left anterior descending coronary artery (LAD), one with lesions in the left circumflex artery (LCX), and 4 with right coronary artery (RCA) lesions. The results were as follows: 1. In all 6 patients with stenotic lesions in the left coronary artery, CSO2-Sat decreased by 5 to 22% immediately after balloon inflation. Significant changes in ic-ECG (ST deviation > or = 0.1 mV) were observed in 5 of the 6 patients, while significant changes in s-ECG (ST deviation > or = 0.1 mV) were observed in only 3 of the 6 patients. The s-ECG did not seem to be sensitive enough to represent myocardial ischemia in the LCX. 2. The interval from the balloon inflation to the significant change was shorter for CSO2-Sat than for the ECGs in 4 of the 5 patients with LAD lesions, except Case 4. The recovery time of CSO2-Sat to the basal level on balloon deflation was longer than the recovery times of ic-ECG and s-ECG. 3. There was no significant change in the CSO2-Sat in 3 of the 4 patients undergoing PTCA for RCA lesions, while significant changes were observed in the ic-ECG and s-ECG in all 4 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1992

[Inverse relationship between coronary flow velocity and myocardial oxygen extraction during intracoronary infusion of papaverine].

The relationship between coronary blood flow velocity (CBFV) and myocardial oxygen extraction (O2-Ext) was investigated during rapid changes of CBFV after intracoronary papaverine infusion. In 6 patients without stenosis of the left anterior descending artery (LAD), one with hypertrophic cardiomyopathy, 2 with syndrome X and 3 with effort angina pectoris, simultaneous measurements of CBFV using the Doppler catheter system and coronary venous oxygen saturation using the fiberoptic catheter system were continuously performed before and during intracoronary infusion of papaverine. When O2-Ext was related to CBFV in every cardiac cycle, there was a good, inverse linear relationship, both in the increase (r = 0.81 +/- 0.24) and decrease (r = 0.93 +/- 0.04) phases of CBFV. The increase in cross-sectional area of segment 6 in the LAD as observed on orthogonal coronary angiograms was 6.0 +/- 2.0%. These results imply that the increase in CBFV during intracoronary papaverine infusion seems parallel to that of coronary blood flow, and that papaverine induces no significant change in myocardial oxygen consumption. Myocardial oxygen extraction in response to changes in coronary flow is regulated readily to meet the myocardial oxygen demand.

Adult↗
PubMed1992

[Are the first repetitive reentrant VPCs a trigger or an initiation of reentrant circuit for VPCs?: Evaluation by Holter ECG in patients with reentrant sustained ventricular tachycardia].

To evaluate whether the first repetitive reentrant VPCs are a trigger or an initiation of a reentrant circuit for VPCs, we studied Holter ECGs in 13 patients with sustained ventricular tachycardia, the morphology of reentrant VPCs, the relationship between the coupling interval (N-V) and the first ventricular cycle length (V-V), and the relationship of the coupling interval (N-V) between single VPC and repetitive VPCs. In 7 patients who showed episodes of repetitive VPCs more than twice on one recording of Holter ECG, most of VPCs in the first and second beats were the same in shape (1195 out of 1466 episodes, 82%). No obvious relationship between the coupling interval (N-V) and the first ventricular cycle length (V-V) was found in 5 patients, whereas a weak inverse relationship (r = 0.32) was found in one patient, and a weak positive relationship (r = 0.38) was found in another patient. In addition, the coupling interval in repetitive VPCs was longer than that in single VPCs in 4 out of 7 patients. These results imply that, in most cases, the first VPC is the expression of initiation of a reentrant circuit for repetitive reentrant VPCs developing spontaneously.

Adult↗
PubMed1992

[A case of atrial standstill associated with combined valvular disease].

A 62-year-old man was admitted to our hospital because of general malaise. The chest X-ray film showed severe cardiomegaly (CTR = 81%). The electrocardiogram demonstrated absence of P wave in 12-leads and regular junctional rhythm with incomplete right bundle branch block. Echocardiogram and color Doppler led to the diagnosis of mitral stenosis and regurgitation, tricuspid regurgitation with enlarged left and right atrium. Cardiac catheterization study revealed elevation of the pulmonary artery wedge pressure and the right atrial pressure without A wave. In the electrophysiologic study, no atrial electrical activity was recorded in the right atrium and the coronary sinus. However, when atrial pacing was attempted at multiple sites with stimulum strength of 10 V, there was no atrial activity at various sites. We considered that the atrial overload due to combined valvular disease for seventeen years had resulted in total and persistent atrial standstill. In this report, we discussed atrial standstill in 67 cases recorded in the medical literatures in our country.

Echocardiography↗
PubMed1991

Respiratory stimulation by female hormones in awake male rats.

The respiratory effect of progestin differs among various animal species and humans. The rat does not hyperventilate in response to exogenous progestin. The present study was conducted to determine whether administration of combined progestin and estrogen prompts ventilatory stimulation in the male rat. Ventilation, blood gases, and metabolic rates (O2 consumption and CO2 production) were measured in the awake and unrestrained male Wistar rat. The combined administration of a synthetic potent progestin (TZP4238) and estradiol for 5 days significantly increased tidal volume and minute expiratory ventilation (VE), reduced arterial PCO2, and enhanced the ventilatory response to CO2 inhalation (delta VE/delta PCO2). On the other hand, respiratory frequency, O2 consumption, CO2 production, and body temperature were not affected. The arterial pH increased slightly, with a concomitant decrease in plasma [HCO3-]. Administration of either TZP4238 or estradiol alone or vehicle (Tween 80) had no effect on respiration, blood gases, and ventilatory response to CO2. The results indicated that respiratory stimulation following combined progestin plus estradiol treatment in the male rat involves activation of process(es) that regulate tidal volume and its augmentation during CO2 stimulus.

Animals↗
PubMed1991

Biochemical analysis of glycosphingolipids in murine uterus and human uterine endometrium with special reference to the sexual cycle.

Uterus is an organ in which cellular proliferation and differentiation are strictly controlled by sex steroid hormones. Since we found a characteristic expression of sulfatide (I 3SO3-GalCer) in the human endometrium during its secretory phase, we decided to analyze developmental changes of glycolipids in murine uteri with special reference to the estrous cycle. Moreover, we analyzed sulfotransferase activity for the synthesis of sulfatide in the endometria in the proliferative and secretory phases and that in the epithelial and stromal cells derived from the human uterine endometrium. In the murine uterus, contents of GlcCer, LacCer, and Gb4Cer were relatively constant both during estrus and diestrus, but those of Gb3Cer and Gg4Cer during estrus were significantly greater than those during diestrus. In contrast, GM3 and sulfatide contents during diestrus were higher than those during estrus. This increase in GM3 and sulfatide during diestrus was characteristically observed in the uterus after sexual maturity. In human uterine endometrium, sulfotransferase activity for the synthesis of sulfatide was found only in the epithelial cells, but not in the stromal cells. Furthermore, the synthetic potential of sulfatide in the human endometrium was higher in the secretory phase than in the proliferative phase. Thus, sulfatide metabolism in human endometrial epithelial cells as well as in the murine uterus is supposed to be well controlled under hormonal regulation, and sulfatide may participate in several reproductive functions of the uterus.

Animals↗
PubMed1991

Effects of carvedilol on serum lipids in patients with essential hypertension.

The purpose of this study was to investigate the effect of carvedilol on serum lipids in patients with mild-to-moderate essential hypertension. Twenty-one patients with blood pressure greater than or equal to 160/95 mm Hg after a 4-week placebo run-in period were initially given 10 mg of carvedilol once daily. The dose was increased to 20 mg after 4 weeks if the target blood pressure was not achieved. The duration of treatment was 12 weeks. After 12 weeks of administration, blood pressure and the pulse rate (PR) declined significantly (blood pressure from 173/105 to 142/91 mm Hg, p less than 0.001; PR from 74 to 67 beats/min, p less than 0.001); however, serum lipids [total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein (HDL), HDL2, and HDL3], lipoprotein fraction (alpha, pre-beta, and beta), apoprotein fraction (A-I, A-II, CII, CIII, and E), and atherogenic index [(total cholesterol - HDL cholesterol) divided by HDL cholesterol] were not altered significantly. There were no side effects reported during the trial. From these results, it can be concluded that carvedilol has no adverse effect on the coronary risk profile as reflected by lipid measurements, and is an efficacious, safe, well-tolerated antihypertensive drug in patients with mild-to-moderate hypertension.

Adrenergic alpha-Antagonists↗
PubMed1991

[A case of adult type of anomalous origin of left coronary artery from pulmonary artery--with a referential consideration to the disease in Japan].

A case of a 33-year-old man with anomalous origin of the left coronary artery from the pulmonary artery (ALCP) was reported with a referential consideration to the adult type of ALCP previously reported in Japan. The patient visited our hospital for further examination of cardiac murmur detected on a mass physical checkup. He was found to have a continuous murmur, the loudest in the left sternal border of 3rd intercostal space, and developed evidence of ischemia during the exercise stress test in the ECG leads of L2, L3, aVF, and V2 through V6. In addition, studies using echocardiography and color Doppler-echocardiography detected a hypertrophied intraventricular septum and a pattern of turbulent blood flow in the proximal pulmonary artery. Cardiac catheterization and aortography proved the existence of ALCP with a markedly developed collateral circulation from the right coronary artery to the left coronary artery. After surgical restoration by ligating the anomalous opening of the left coronary artery, and by bypass grafting to the left coronary artery, it was clear that dilation and kinking of the right coronary artery was lessened and hypoperfusion in the anterior left ventricular wall was improved. As far as we know, this case is the 35th of adult type ALCP reported in our country. Results from this case and others suggest that early detection and therapy for adult type ALCP is important from the point of view preventing ischemic progression, and indicate that restoration by ligation and bypass grafting may be one of the effective surgical procedures for ALCP.

Adult↗
PubMed1991

[A case of Ramsey Hunt syndrome with multiple cranial nerve paralysis and acute respiratory failure].

The authors report a 56-year-old woman with Ramsey Hunt syndrome with multiple cranial nerve paralysis and acute respiratory failure. Five days before admission, she experienced right otalgia and right facial pain and consulted an otolaryngologist of our hospital, who diagnosed the illness as acute parotitis and laryngopharyngitis. One day before admission, she experienced mild dyspnea and general fatigue and came to our hospital emergency room. A chest X-ray film revealed no abnormalities but some blisters were observed around her right ear. The next day, her dyspnea became more severe and she was admitted. A chest X-ray film on admission revealed right lower lobe consolidation, and neurological examination disclosed multiple cranial nerve paralysis, i.e., paralysis of the right fifth, seventh, eighth, ninth, tenth, eleventh, twelfth and left tenth cranial nerve. The serum titer of anti-herpes zoster antibody was elevated to 1,024, and the patient was diagnosed as having Ramsey Hunt syndrome with multiple cranial nerve paralysis. Arterial blood gas analysis revealed hypoxemia with hypercapnea, which was considered to be due to aspiration pneumonia and central airway obstruction caused by vocal cord paralysis. Mechanical ventilation was soon instituted and several antibiotics and acyclovir were administered intravenously, with marked effects. Three months after admission, the patient was discharged with no sequelae except mild hoarseness. Patients with herpes zoster oticus, facial nerve paralysis and auditory symptoms are diagnosed as having Ramsey Hunt syndrome. This case was complicated by lower cranial nerve paralysis and acute respiratory failure, which is very rare.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1991

[Coronary collateral function evaluated by coronary hemodynamics and myocardial lactate metabolism during rapid atrial pacing].

To elucidate coronary collateral function in the ischemic myocardium, we studied coronary hemodynamics and myocardial lactate metabolism of the collateral-dependent myocardium before and during rapid atrial pacing. Subjects consisted of 38 patients who were categorized into 3 groups according to their coronary and coronary collateral arteriographic findings: 14 patients with normal coronary arteriograms (Group A), 15 with significant stenosis in the left anterior descending coronary artery (LAD) without collaterals (Group B), and 9 with LAD stenosis and collaterals (Group C). Estimates of cross-sectional area (CSA) obtained from the orthogonal coronary arteriograms, and the great cardiac vein flow (GCVF) and myocardial lactate extraction ratio (MLER) before and during rapid atrial pacing were used as parameters to evaluate coronary stenosis. The results were as follows: 1. The cross-sectional areas in Groups B and C were 86% and 91% of that in Group A, respectively. 2. In Group B, there was a good linear relationship between cross-sectional area and % delta GCVF, as shown in % delta GCVF = 2.90 + 36.22 x CSA (r = 0.61, p < 0.05). This relationship was modified in Group C, increasing % delta GCVF against CSA. 3. Myocardial lactate extraction ratio in Groups B and C decreased significantly after rapid atrial pacing, while, it remained unchanged in Group A. This ratio after rapid atrial pacing did not differ significantly between the 2 groups. 4. In 3 of 4 patients with total LAD occlusions, GCVF and anterior coronary resistance before and during rapid atrial pacing were similar to those of Group A.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Pacing, Artificial↗
PubMed1991

[Correlations between redistribution areas observed on exercise thallium-201 myocardial SPECT images and the coronary collateral circulations in patients with myocardial infarction].

The significance of coronary collateral circulation for redistribution in the infarcted zone was evaluated in 16 patients with history of myocardial infarction and severe stenosis (> or = 90%) of the coronary artery. Redistribution areas were quantitatively measured using the redistribution ratios and redistribution indices on the infarction-redistribution map obtained by thallium-201 scintigraphy with single photon emission computed tomography. Coronary collateral findings were categorized in 4 classes according to the Rentrop's grading. There was good, positive linear correlation between the redistribution ratio (Y) and collateral grading (X) (Y = 0.21X + 0.10, r = 0.92, p < 0.01). The redistribution index (X) also correlated well with the collateral grading (Y) using a good, positive quadratic equation (Y = 0.32X2 + 0.24X + 0.04, r = 0.89, p < 0.01). These results suggest that the measurements of the redistribution areas in the ischemic zone in myocardial infarction correlated well with collateral perfusion. Collateral perfusion severer than Rentrop's grade 2 markedly reduces the severity of ischemia and increases redistribution areas.

Collateral Circulation↗
PubMed1991

[Clinical and pathophysiological significance of neutrophil elastase in sputum and the effect of erythromycin in chronic respiratory diseases].

The concentration and activity of neutrophil elastase (NE) in sputa were measured in 24 patients with chronic respiratory diseases such as diffuse pan-bronchiolitis, bronchiectasis and and chronic bronchitis. The results were compared to the clinico-pathophysiological parameters such as clinical impairment score, concentration of albumin and ciliary transport velocity of the sputum. Furthermore, the relationship between the post-therapeutic change of NE in sputum and clinical effect of erythromycin (EM) was investigated in the same cases. Physico-chemical properties of the sputum, including rheological characteristics, mucus transport velocity, phospholipid composition, concentration of albumin and fucose were also analyzed before and after EM therapy. There was a significant positive correlation between NE in sputum and the clinical impairment score, which suggested that the concentration and activity of NE in sputum reflected the clinical severity in such diseases. The concentration and activity of NE also had significant positive and negative correlation to the concentration of albumin and ciliary transport velocity, respectively. Therefore, it was considered that NE in airway could bring the leakage of albumin from serum and interfere with mucociliary transport. The patients were divided into responders (n = 12) and non-responders (n = 12) after EM therapy based on the change of the clinical impairment score. The clinical effect of EM in chronic respiratory diseases was not associated with its bacteriostatic action, but with the quantitative and qualitative suppression of sputum NE. The decrease of the adhesive properties of the sputum, which was observed in responders after administration of EM, was considered to depend on the reduction of the concentration of albumin in sputum. Concerning the phospholipid composition of sputum, sphingomyelin and phosphatidyl-ethanolamine, which had been suggested to be components of serum and cellular membrane, had a tendency to decrease in responders. The proportion of phosphatidylcholine increased in responders. The improvement of ciliary transport velocity of the sputum, which was noted in responders, was probably due to the results mentioned above. In non-responders, these findings were not observed after EM therapy. EM had no influence on the production, release and activity of NE as a result of in vitro experiments using human peripheral neutrophils. Neutrophil chemotaxis was however suppressed after incubation with EM. These results suggest that the mechanisms of the effect of EM is not direct action on NE but through suppression of neutrophil chemotaxis.

Adult↗
PubMed1991

[A case of Schönlein-Henoch purpura with myocardial complications].

A rare case of Schönlein-Henoch purpura with myocardial complications was reported. A 64-year-old man was admitted to our hospital for further examination of hematuria, associated with arthralgia, proteinuria, and previous episodes of anasarca and orthopnea. The examinations revealed moderate renal dysfunction due to mesangial proliferative glomerulonephritis secondary to Schönlein-Henoch purpura. In addition, the patient proved to have cardiac dilatation and dysfunction of the left ventricle. The histological examination of the right ventricular subendocardium sampled by myocardial biopsy showed myocardial damage, suggesting the invasion of microvasculitis in Schönlein-Henoch purpura to the peripheral coronary vessels. These findings indicate that myocardial damage induced in the patient may be one of the complications caused by Schönlein-Henoch purpura.

Cardiac Catheterization↗
PubMed1991

[Coronary venous oxygen saturation dynamics during intracoronary infusion of ergonovine or acetylcholine in vasospastic angina].

We investigated changes in coronary venous oxygen saturation (CSO2-Sat) dynamics during intracoronary infusion of ergonovine (ERG) or acetylcholine (ACh) in patients with vasospastic angina. In 16 patients with suspected vasospasm in the left coronary artery, intracoronary ERG injection provoked vasospasm in 4 out of 6 patients, and intracoronary ACh in 6 out of 11 patients. A gradual decrease in CSO2-Sat, anteceding angina and ischemic ECG evidence, was characteristic in ERG-induced vasospastic patients, while no significant change of CSO2-Sat was observed in non ERG-induced patients. Intracoronary infusion of ACh was followed in all 11 patients by a transient increase in CSO2-Sat, suggesting decreased myocardial oxygen extraction due to increased coronary blood flow with ACh. However, earlier and sudden decreases in CSO2-Sat below the control levels were characteristic in 6 patients with ACh-induced vasospastic angina. These findings suggest that effects of ERG and ACh on coronary flow dynamics are essentially different although both drugs can provoke vasospasm.

Acetylcholine↗