Search PubMed⌕ Search

Biomedical subjects

M Miyamoto

Publications and source records attributed to M Miyamoto.

At least 379 records · Page 21Linked to original sources
PubMed1990

Induction of protective immunity in animals vaccinated with recombinant vaccinia viruses that express PreM and E glycoproteins of Japanese encephalitis virus.

A cDNA clone representing the genome of structural proteins of Japanese encephalitis virus (JEV) was inserted into the thymidine kinase gene of vaccinia virus strains LC16mO and WR under the control of a strong early-late promoter for the vaccinia virus 7.5-kilodalton polypeptide. Indirect immunofluorescence and fluorescence-activated flow cytometric analysis revealed that the recombinant vaccinia viruses expressed JEV E protein on the membrane surface, as well as in the cytoplasm, of recombinant-infected cells. In addition, the E protein expressed from the JEV recombinants reacted to nine different characteristic monoclonal antibodies, some of which have hemagglutination-inhibiting and JEV-neutralizing activities. Radioimmunoprecipitation analysis demonstrated that two major proteins expressed in recombinant-infected cells were processed and glycosylated as the authentic PreM and E glycoproteins of JEV. Inoculation of rabbits with the infectious recombinant vaccinia virus resulted in rapid production of antiserum specific for the PreM and E glycoproteins of JEV. This antiserum had both hemagglutination-inhibiting and virus-neutralizing activities against JEV. Furthermore, mice vaccinated with the recombinant also produced JEV-neutralizing antibodies and were resistant to challenge with JEV.

Amino Acid Sequence↗
PubMed1990

Decrease in rat submandibular acinar cell volume during ACh stimulation.

Changes in acinar cell volume were measured in the perfused submandibular gland of the rat at 23 degrees C during salivary secretion induced by acetylcholine (ACh). Cellular volume was monitored by two methods: the impedance method and the morphometric method using video-enhanced contrast optical microscopy. Both measurements revealed a decrease in acinar cell volume in response to 1 microM ACh. Within the 1st min of stimulation, secretion increased to the initial maximum (initial secretion), and cell shrinkage occurred. During sustained stimulation, secretory rate and cell volume were maintained at the plateau level (steady secretion). The decrease in cell volume was 71.8 +/- 2.9% of resting volume (means +/- SE, n = 8) as measured by the impedance method and 76.1 +/- 2.0% (n = 20) as measured by the morphometric method. With the removal of ACh, cell volume increased to 111.6 +/- 2.7% (n = 8) of the prestimulation level as measured by the impedance method and 108.8 +/- 1.5% (n = 20) as measured by the morphometric method, and then recovered to the prestimulation level slowly. The weight of the gland decreased significantly during stimulation. These findings proved that volume decrease occurred during stimulation. The measurement of cell volume gave the net fluid flux of the acinar cell compartment. The net fluid flux and the rate of salivary secretion gave an estimation of the fluid influx across the basolateral membrane. These findings suggest that a transcellular route for fluid secretion exists in the salivary gland.

Acetylcholine↗
PubMed1990

Antihypertensive effect of CS-905, a novel dihydropyridine calcium blocker, in conscious hypertensive dogs.

CS-905, (+-)-3-(1-diphenylmethylazetidin-3-yl)5-isopropyl 2-amino-1,4-dihydro-6-methyl-4-(m-nitrophenyl)-3,5-pyridine-dicarboxy lat e, is a novel dihydropyridine calcium blocker. Both CS-905 and nicardipine, when administered orally, produced a dose-dependent fall of blood pressure in conscious perinephritic hypertensive dogs. Unlike the hypotensive effect of nicardipine, that of CS-905 has a gradual onset and is long-lasting, with little increase in the heart rate and plasma renin activity (PRA). The lack of both tachycardia and increase of PRA is probably mostly due to the slow onset of antihypertensive action following CS-905.

Animals↗
PubMed1990

Hemodynamic changes following long-term administration of CS-905, a novel dihydropyridine calcium blocker, in conscious SHR.

To investigate the central and regional hemodynamics after long-term administration of CS-905, a novel calcium blocker, we administered the agent (1 and 3 mg/kg/day) for 15 weeks in spontaneously hypertensive rats. At the end of the dosing period, hemodynamic changes were examined using the radioactive microsphere technique. CS-905 produced a sustained dose-dependent antihypertensive effect without inducing tolerance during the 15-week dosing period and prevented cardiac hypertrophy. The agent increased cardiac output, decreased blood pressure and thus decreased total peripheral resistance in a dose-related manner. Regional blood flows measured by the microsphere technique were increased in the kidney and brain despite the lowered blood pressure. There was no organ where regional blood flow was decreased. These changes after chronic treatment with CS-905 would be beneficial in the long-term therapy of hypertension.

Animals↗
PubMed1990

Myocardial preservation: a comparison of oxygenated crystalloid and blood cardioplegia.

The purpose of this experiment was to compare myocardial protective effect after global ischemia using oxygenated crystalloid (CCcO2) and an oxygenated blood (BCcO2) cardioplegic solutions. Post-ischemic ventricular performance was studied in 2 equal (n = 7) groups of dogs subjected to 120 min of global ischemia induced at average myocardial temperatures of 8 degrees C in the CCcO2 group and 18 degrees C in the BCcO2 group. Left ventricular (LV) function included analysis of LV systolic function (global and regional function), LV diastolic function (chamber and myocardial stiffness) and LV relaxation was measured by sonomicrometry and Millar micrometers. Data were processed with a Dec PDP-11/23 computer. In vitro oxygen content (Vol%) measured 3.2 +/- 1.0 (CCcO2) and 9.5 +/- 0.3 (BCcO2). Percent recoveries of LV global function (LVSP, loop area, % shortening, LV dp/dt, mean VCF and E max) in the CCcO2 group were approximately the same as those in the BCcO2 group. There were no significant differences in LV regional function (loop area and % shortening) after ischemia between the two groups. The chamber and myocardial stiffness after ischemia in the CCcO2 group were almost the same as the baseline values. Values in the BCcO2 group were reduced significantly compared to the baseline level. There were significant differences in post-ischemic chamber and myocardial stiffness between the two groups. Post-ischemic maximum negative LV dp/dt in both groups decreased significantly compared to the baseline values. However, the time constant and diastolic interval after ischemia in both groups were approximately the same as the baseline values. We conclude that there were no significant differences in myocardial protective effect between the CCcO2 and BCcO2 groups, and both methods preserved the ischemic myocardium well.

Animals↗
PubMed1990

[The clinical and etiological study on juvenile periodontal disease].

Seven juvenile periodontally diseased patients were evaluated for clinical, microbiologic and local or systemic host factors. Three patients showed the localized from of periodontitis clinically and radiographically and by deep periodontal pockets associated with the molars and incisors. Four were in the generalized froms, in which in most cases all teeth were affected. The results in both diseased froms on the predominant cultivable subgingival microflora, the composition of which was not different from that in adult periodontitis, consisted of significantly increased proportions of Gram-negative anaerobic rods, Bacteroides sp. and B. gingivalis, Haemophilus sp. and H. actinomycetemcomitans were detected in 1/3 of the localized and 2/4 of the generalized periodontitis. They were of no value in distinguishing activity that enhanced disease in the generalized from. Elevated serum IgG responses were noted with B. gingivalis. No markedly functional abnormalities of neutrophils from peripheral blood have been demonstrated, however it might function with systemic factors, like an insulin-dependent diabetes. Morphologic characteristics of the oral and periodontal tissue in localized periodontitis were that the pattern of destruction was confined to specific teeth groups characterized by extensive the bucco-lingual width ratio of the dental crown to alveolar bone width. These observations indicate that the generalized form of juvenile periodontitis lesions were associated not only with the presence of subgingival bacteria, but also with conditions such as local morphologic and systemic or constitutional factors, individual variation in relation to destructive and protective aspects of the defense mechanisms.

Adolescent↗
PubMed1990

Morphology of the transplantable colon carcinoma derived from the spontaneous colon carcinoma of WF-Osaka rat strain.

Two lines of the transplantable colon carcinoma were established. They were from the spontaneous colon carcinoma of WF-Osaka rat strain which had been set up in our laboratory. Transplant procedure was carried out mainly by the intraperitoneal implantation, and, in particular, the treating with a specified way of HIBITANE for disinfection against colonic flora at the primary transplant was quite effective. The growth speed of the transplanted colon carcinoma was slow at first and gradually increased its speed. Histology of the transplanted tumor altered gradually from the glandular pattern at first to the medullary pattern in the late stage of the transplant generation. Each tumor node in the late stage of transplant generation was composed of numerous small nodules separated by thin stromal tissue. Squamous metaplasia and central necrosis were seen in the center of the small nodules. Two lines of the transplantable colon carcinoma were named C1 and C2 and the former is at now the 101th generation and the latter is at the 107th generation.

Animals↗
PubMed1990

Analysis of Japanese encephalitis (JE) virus genome and implications for recombinant JE vaccine.

From the information of nucleotide sequences and deduced amino acid sequences of flaviviruses including JEV, we can postulate processing mechanisms of a polyprotein translated from single long open reading frame of the genome and mechanisms of construction of antigenic structures of structural proteins with biologically active forms after these proteins are translated. The results of comparative analysis of amino acid sequences among flaviviruses and epitope analysis on the E proteins which are the most important antigens for protective immunity suggest that the E protein of flaviviruses may have a similar structure closely related to each other. PrM and E proteins which had predictable signal sequences upstream on the N terminals were expressed with antigenically active form and molecular size the same as the authentic ones by the recombinant viruses. However, the recombinant viruses which had no such signal sequence expressed unprocessed proteins with antigenically denatured forms. These results suggest that normal proteolytic processing is needed to construct biologically active structures of JEV structural proteins. The E proteins which were expressed by the recombinant viruses as antigenically active form could elicit nutralizing and HI antibodies in animals and protective immunity in mice. The recombinant vaccinia viruses which express the E protein could induce strong immunologic memory against the E protein in mice. These results indicate that the development of a new type of vaccine against JEV will become possible in future.

Amino Acid Sequence↗
PubMed1990

[Clinical evaluation of midazolam as an anesthetic for geriatric patients and patients with hepatic dysfunction].

This study evaluated the usefulness of midazolam in inducing a anesthetic state in 60 patients who underwent surgery under general anesthesia. The patients were divided into 3 groups; a geriatric group, a hepatic dysfunction group, and a control group (adults without complications). To induce sleep 0.15 mg.kg-1 or 0.2 mg.kg-1 of midazolam was administered intravenously to all three groups. After the administration of midazolam, the mean time for obtaining absence of response to calling name and absence of ciliary reflex were not significantly different in the three groups. The pulse rate and respiratory rate also did not change remarkably. But significant decreases were observed in the systolic blood pressure and tidal volume in all three groups. However, they were not significantly different among the three groups. These results indicate that midazolam is a useful drug for inducing anesthetic state in geriatric patients and patients with hepatic dysfunction.

Adult↗
PubMed1990

Crystalline light-chain deposition and amyloidosis in the thyroid gland and kidneys of a patient with myeloma.

A 48-year-old Japanese woman died of multiple myeloma (lambda light-chain type) with chronic renal failure. Histological examination revealed deposition of a homogeneous substance and crystals in the kidneys and thyroid gland. The homogeneous substance was stained with Congo red after permanganate treatment but did not stain with antibody to amyloid A protein, and it was recognized as AL-type amyloid. Crystals were not stained with Congo red, but crystals were stained with antibody to the lambda light chain. Since AL-type amyloid is considered to be derived from a myeloma light chain, the present case showed two different types of deposition, both of which were derived from the same myeloma protein.

Amyloid↗
PubMed1990

[Effect of glucagon on bile acid after hepatectomy in patients with hepatocellular carcinoma associated with cirrhosis].

Hepatic function frequently becomes worse, after hepatectomy in patients with hepatocellular carcinoma associated with cirrhosis. We usually use insulin and glucagon to treat patients with poor hepatic function, so we examined hepatic function in these patients in relation to bile acid metabolism. 1) Total serum bile acid levels were increased in patients with cirrhosis, and serum GCDCA, TCDCA values were especially high. After surgery, they rose even higher. 2) Glucagon was shown to stimulate C-AMP and decreased total serum bile acid, and especially serum GCDCA and TCDCA values.

Bile Acids and Salts↗
PubMed1990

[The effect of the co-existence of verapamil and residual propranolol on the left ventricular contractility].

The combined effect of the residual propranolol, which was administrated up to the coronary revasculization, and verapamil, anti-supraventricular tachycardia drug, on the left ventricular contractility was evaluated with left ventricular end-systolic pressure-diameter relationship. Methods; Eighteen sheep were instrumented with ultrasonic crystals on the anterior and posterior wall, endocardium and epicardium. A pressure transducer was placed in the left ventricle. Propranolol (0.15 mg/kg) (n = 6) or verapamil (0.15 mg/kg) (n = 6) or both drugs (n = 6) were administrated intravenously, and cardiac function was evaluated. Results; In combined group, end-systolic pressure-diameter ratio (Emax) was significantly decreased (2.95 +/- 0.24 mmHg/mm) as compared to the control group (7.95 +/- 0.83), propranolol group (6.27 +/- 0.78), and verapamil group (4.54 +/- 0.77). Conclusion; Co-existence of propranolol and verapamil significantly decreased cardiac contractility. Therefore verapamil should be administrated carefully in the presence of residual propranolol, and the co-existence of both drugs must be limited.

Animals↗
PubMed1990

[A case of triple carcinomas: stomach carcinoma surgically removed, renal tumor, and carcinoma of the remnant stomach].

Reported is the case of a 57-year-old male patient, who manifested tarry stool and who had undergone a subtotal gastrectomy at our hospital in 1983 for an early carcinoma, type IIc, which proved to be a well differentiated tubular adenocarcinoma. Three years later, he returned complaining of epigastralgia, although no evidence of a recurrence could be seen. An abdominal ultrasonogram and a CT scan, however, revealed a right renal tumor and he subsequently underwent an operation for the removal of a renal cell carcinoma, a clear cell type. In 1988, he again was readmitted to hospital, this time because he easily became fatigued. An upper GI series and gastroscopy located a polypoid lesion in the remnant stomach. Thus, a total gastric resection was performed, and the lesion was diagnosed as being a well differentiated tubular carcinoma, an early gastric cancer, type I. Triple carcinomas are very rare, and the details of this case are discussed.

Adenocarcinoma↗
PubMed1990

[A successful removal of a left atrial massive ball thrombus caused by mitral stenosis].

A 66-year-old female with a mitral stenosis and a left atrial massive ball thrombus is presented. She was admitted due to a transient right hemiplegia and a speech disturbance. This thrombus had been detected preoperatively by an echocardiogram and a left atriography. A mitral valve replacement using a Björk-Shiley valve 27 mm, accompanied with the removal of the thrombus was performed. The ball thrombus was dark red, 55 x 35 x 32 mm in size and 15 g in weight. After the surgery, the patient progressed well. Because of the high frequency of peripheral embolism and of sudden death, a left atrial ball thrombus should be removed immediately.

Female↗
PubMed1990

[Noonan syndrome associated with atrial septal defect, ventricular septal defect and pulmonary stenosis--a case report].

A 10 year old girl with diagnosis of Noonan syndrome was admitted to our hospital because of easy fatiguability and cardiac murmur. She had a peculiar face with hypertelorism, saddle nose, webbed neck and kyphosis. Chromosomal analysis demonstrated normal 46 XX pattern. Associated cardiac anomalies in this case were atrial septal defect, ventricular septal defect and pulmonary stenosis caused by pulmonary valvular dysplasia. The cardiac anomalies were corrected successfully and postoperative clinical course was uneventful.

Child↗
PubMed1990

[Significance of measuring Cu, Zn-superoxide dismutase (SOD) levels in open heart surgery].

Cu, Zn-SOD levels, free hemoglobin (Hb) and CPK-MB were measured in 18 patients undergoing open heart surgery. In order to evaluate the serum level of Cu, Zn-SOD, the ratio of Cu, Zn-SOD/free Hb was used to eliminate an influx of Cu, Zn-SOD released from erythrocytes during cardiopulmonary bypass. The value of Cu, Zn-SOD/free Hb was decreased significantly 30 minutes after aortic declamping and the minimal value was indicated 1 hour after the termination of cardiopulmonary bypass compared with the preoperative status. We thought that the decrease was due to the consumption of SOD competing against free radical generation. The correlation between the minimal value of Cu, Zn-SOD/free Hb and the ischemic time was apparent but the correlation between the minimal value of Cu, Zn-SOD/free Hb and the value of peak CPK-MB was not determined. It was suggested that the serum free radicals were not only derived from the heart but also from the lung or other parts of the body during open heart surgery.

Adult↗