Biomedical subjects

S Onodera

Publications and source records attributed to S Onodera.

At least 145 records · Page 8Linked to original sources

PubMed1992

[A case of obstructive sleep apnea syndrome with increased lung water content during sleep].

A 57-year-old man was admitted complaining of sleep disturbance. All night polysomnography showed a pattern of obstructive sleep apnea. We performed 201Tl scintigraphy to evaluate hemodynamic change and degree of stress on the right ventricle during sleep, and compared it with a 201Tl scintigram during wakefulness. We recognized 201Tl uptake by the lung in the 201Tl scintigram during sleep, but not during wakefulness. To determine the mechanism of 201Tl uptake by the lung during sleep, we measured lung water content during sleep by double indicator dilution method (Nihon Koden, NTV-1100). We recognized an increase of lung water content during sleep. We consider that the increase of lung water content during sleep is caused by sleep apnea, probably by hemodynamic change due to negative pleural pressure swings during sleep apnea.

Extravascular Lung Water↗

PubMed1992

[Effect of potassium channel openers on hypoxic pulmonary vasoconstriction].

The ATP-sensitive potassium channel (K+ATP) has been suggested as an important mechanism for the reactivity of vascular smooth muscle. We investigated the effects of K+ channel openers (lemakalim, pinacidil) on hypoxic pulmonary vasoconstriction (HPV) and angiotensin II (Ag II) induced vasoconstriction in isolated rat lungs (Sprague-Dawley rats: 300-450 g). Ventilation with hypoxic gas (2% O2, 5% CO2) was performed for 6 min after the injection of Ag II (0.1 microgram). Isolated lungs were perfused under constant flow (0.04 ml/g/min) using 20 ml of blood from donor rat. The perfusion pressure was used as the pulmonary artery pressure. Lemakalim or pinacidil was pre-administered through the reservoir. Pretreatment with pinacidil (10(-4) M) or lemakalim (10(-5) M) inhibited the pressor response to hypoxia, but did not inhibit the response to angiotensin II. Although the effect of lemakalim on HPV was reversed by administration of glibenclamide (10(-5) M) or tolbutamide (10(-3) M), the effect of pinacidil on HPV was not influenced by either drug. These results suggest that 1) K+ channel openers (lemakalim and pinacidil) inhibit the pressor response to hypoxia, and 2) lemakalim seems to act through K+ATP, whereas pinacidil may have other mechanisms of inhibition of vascular smooth muscle contraction. K+ATP may play an important role in the regulation of pulmonary vascular reactivity to hypoxia.

Angiotensin II↗

PubMed1992

[Left ventricular aneurysm with normal coronary arteriogram after myocardial infarction].

Left ventricular aneurysms after myocardial infarction are generally considered one of the complications of severe coronary artery disease. Postinfarction ventricular aneurysms with normal coronary arteriogram are rare. Only a few cases have been reported previously in Japan. We examined the incidence and the clinical characteristics of postinfarction ventricular aneurysms without coronary obstruction. Among the consecutive 1800 patients studied in our laboratory with selective coronary cineangiography and left ventriography, we found 5 (4 male, 1 female) patients with left ventricular aneurysms with no or minimal coronary arterial obstruction. The patient's ages ranged from 34 to 83 with a mean of 59. Interestingly, no patient had prior anginal history, and every case occurred with a first sudden attack of chest pain. The likely mechanisms causing the development of myocardial infarction were coronary spasm and/or thromboembolic accident. One patient, in whom a coronary induction test was performed, showed positive findings. It is possible that poor collateral circulation and well preserved contraction of viable myocardium in these patients bring about the formation of left ventricular aneurysm after myocardial infarction with normal coronary arteriogram.

Adult↗

PubMed1992

[A case of humidifier lung associated with BHL].

We encountered a rare case of hypersensitivity pneumonitis associated with bilateral hilar lymphadenopathy (BHL). The patient was a 53-year-old male, who developed dry cough and shortness of breath when using a humidifier since 1982. He was admitted to our hospital for further evaluation in 1987. Chest X-ray films showed BHL and ground glass appearance in the bilateral lung fields. Pulmonary function test indicated disturbance of diffusing capacity. Transbronchial lung biopsy revealed interstitial pneumonitis, and lymph node biopsy by mediastinoscopy showed lymphoid sinus histiocytosis without noncaseating granuloma. Provocation test using the humidifier was positive, and the diagnosis of humidifier lung with BHL was made.

Alveolitis, Extrinsic Allergic↗

PubMed1992

[Case report of angiomyolipoma of the posterior upper mediastinum].

A case of posterior upper mediastinal angiomyolipoma is reported. The patient was an asymptomatic 63-year-old female, in whom an abnormal shadow was detected on chest x-ray at medical examination. On computed tomogram, the mass was located in the right paravertebral upper mediastinum, and its density had a CT-number of 12. It had high MRI intensity. Since there remained a possibility of malignancy, thoracotomy was carried out. The resected tumor was soft in consistency and the size was 20 x 23 x 37 mm. Histological examination showed that the mass was composed of fatty tissue, smooth muscle, and vascular tissue. Therefore, the tumor was diagnosed as angiomyolipoma. Although angiomyolipomas are often found in the kidney, those in the mediastinum are very rare and there have been only 2 cases reported in the literature. We consider that angiomyolipoma is rare, but important in the differential diagnosis of mediastinal tumors.

Aged↗

PubMed1992

[A case of idiopathic aneurysm of the inferior vena cava].

Congenital aneurysms of the inferior vena cava (IVC) are very rare, and to our knowledge, only 4 cases have been previously reported. We describe the fifth case of fusiform aneurysm and briefly review the literature. A 62-year-old woman was admitted to our hospital for investigation of a mass shadow on the right hemidiaphragm on a chest roentgenogram. CT, MRI, and DSA examinations revealed an aneurysmal dilatation of the IVC measuring 51x50x38 mm inferior to the right atrium, and the diagnosis of fusiform aneurysm of the IVC was made. The newer imaging techniques of CT, MRI, and DSA have facilitated the diagnosis of this abnormality.

Aneurysm↗

PubMed1992

[Atrioventricular block in acute inferior myocardial infarction].

The underlying mechanism of atrioventricular block (AVB) in acute inferior myocardial infarction (AIMI) is not clearly understood. In 33 (27 males and 6 females) of 123 patients with AIMI, second and/or high degree AVB was observed. In 14 of the 33 patients (42%), AVB transiently appeared within 24 hours after the onset of AIMI. In 13 patients (39%) AVB appeared after 24 hours. In the remaining 6 patients (18%), AVB appeared within 24 hours and disappeared thereafter. Among these 3 groups, there were no significant differences in age, sex, serum enzymes, the appearance of high degree AVB, pump failure or Forrester's classification II, III and IV and the necessity of temporary pacing. One mg of atropine sulfate was administrated intravenously 35 times in 19 patients. When AVB improved or the ventricular rate increased more than 30%, the drug was regarded as effective. Atropine was more effective when administrated after 24 hours (11%, less than or equal to 24 hours vs 60%, greater than 24 hours, p less than 0.05), and in patients with a slight degree of AVB (28% in high degree vs 80% in second degree, p less than 0.05) and rapid ventricular rate during high degree AVB (0%, less than 40/min vs 45%, greater than or equal to 40/min, p less than 0.05). In the 6 patients not responding to atropine, 250 mg of aminophylline was given intravenously for 15 min. The effect was not seen in 4 patients, including 3 patients to whom it was administrated within 3 days after the onset of AIMI, and one patient to whom it was given on the 5th day. Aminophylline improved atrioventricular conduction on the 5th to 10th day after the onset of AIMI in 2 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine↗

PubMed1992

[Minocycline-induced pneumonia and pleurisy--a case report].

A 24-year-old woman had been treated with minocycline (MINO) for acute upper airway infection. Two days after the start of MINO therapy, she developed fever, cough, dyspnea, and bloody sputum. Her chest X-ray film revealed bilateral pleural effusions and butterfly shadow, and chest computed tomography revealed markedly increased density of pulmonary tissue in the central lung fields. Arterial blood gas analysis demonstrated severe hypoxemia. The characteristics of the pleural effusion were exudative. Based on the history of her illness and the chest X-ray findings, in addition to the laboratory findings of leukocytosis with eosinophilia and increased serum IgE, drug-induced pneumonia was suspected. Once the treatment with MINO was discontinued, her symptoms, laboratory data, and chest X-ray findings improved rapidly. Microscopic examination of a transbronchial lung biopsy specimen showed increased alveolar septal thickness with formation of Masson's bodies. Although the result of a lymphocyte stimulation test was negative for MINO, the skin test was positive for immediate response. Because of her clinical course, the possibility of induction by other drugs was excluded. This patient was therefore diagnosed to have MINO-induced pneumonia. To date, ten cases of MINO-induced pneumonia have been reported, but no previous case was associated with pleurisy.

Acute Disease↗

PubMed1991

Separation and characterization of sialic acid-containing salivary-type amylase from patients' sera with immunoglobulin A-type myeloma.

Isoamylases, with an abnormal anodic migration, were detected by an electrophoretic technique in the sera from two patients with immunoglobulin A-type myeloma. The abnormal isoamylase bands migrate towards the anode faster than the salivary isoamylase (S2) band and were stained more strongly than the S2 sub-band. The abnormal isoamylase could be separated from patients' sera by using size-exclusion high-performance liquid chromatography. The serum abnormal isoamylases were showed to be sialic acid residues containing amylase, after the study of treatment with neuraminidase (EC 3.2.1.18), and to be salivary-type amylase, after the study of reaction with human salivary monoclonal antibody. The abnormal bands were not detected in the saliva from one patient. The two patients had no detectable malignancies except myeloma. These findings strongly suggest that the sialic acid-containing salivary-type amylases were produced ectopically from myeloma cells. In this regard the ectopic amylase production by myeloma cells is discussed.

Aged↗

PubMed1991

Prolonged period of global ischemia causes no change in the GTP-binding proteins in the isolated perfused rat heart.

The response of the beta-adrenoceptor transduction system to global ischemia for 40 min was investigated in isolated working heart of rat. The enhancement of beta-adrenoceptors was not observed in the ischemic myocardium. A depression of forskolin-stimulated adenylate cyclase enzyme occurred with global ischemia, but no change in Gs or Gi2 was detected. Thus, the present in vitro ischemic heart model may not necessarily reflect the identical milieu induced by the in vivo myocardial ischemia.

Adenylyl Cyclases↗

PubMed1991

Characterization and determination of organic compounds in the mutagenic XAD-2 extracts of drinking water.

Amberlite XAD-2 extracts, which exhibit mutagenicity in the Ames assays, of drinking water sampled each month during the period from April 1988 to March 1989 were studied in order to characterize and determine the organic pollutants. The major organic pollutants were phthalate ester plasticizers such as dibutyl and di(2-ethylhexyl) phthalate. Several polynuclear aromatic hydrocarbons (PAHs) and the organocholorine pesticide oxadiazon were also identified to be present at low concentrations. The XAD-extractable and chromatographable organic pollutants were found to be composed of PAHs with a mean concentration of 0.136 micrograms/l(ca. 10% of the total amount of organic compounds detected), phthalates with a mean value of 0.405 micrograms/l(ca. 30%) and other compounds with a mean value of 0.845 micrograms/l(ca. 60%). The concentrations and compositions of these organic pollutants were correlated with the effective rainfall content of the river and with the water temperature.

Ion Exchange Resins↗

PubMed1991

Characterization of Mengo virus neutralization epitopes.

A set of four monoclonal antibodies which neutralized the infectivity of Mengo virus was used to select 20 non-neutralizable (escape) mutants. Altered amino acids were identified by sequence analyses of the capsid-coding regions of the mutant virus genomes. Mutations were found predominantly in proteins VP2 and VP3, while mutations in VP1 were detected only as second mutations. The Mengo virus VP2 mutations at amino acid residues 2144, 2145, 2147, and 2148 align with site Nlm II in human rhinovirus-14 and site 2 in polioviruses 1 and 3. The mutation at 2075 as well as those at 3057, 3061, and 3068 in VP3 correspond to site 3 in poliovirus. These alignments notwithstanding, the results of cross-neutralization experiments indicate the existence of a single composite neutralization site on the Mengo virion. Considering the three-dimensional structure of the Mengo capsid, the amino acids which are altered in the escape mutants are all exposed on the outer surface and none are found in the "pit," the probable site for binding of a cellular receptor. The VP3 mutations are located in the VP3 "knob" and the VP2 mutations on a nearby ridge. Together these mutations define a set of epitopes within a single composite antigenic determinant which forms a crescent-shaped area around the three-fold icosahedral axes of the Mengo virion.

Animals↗

PubMed1991

Disposition of amino acid synaptic transmitters, acetylcholine and substance P in the LM-suprageniculate nuclear complex of the cat's thalamus.

Immunocytochemical analysis with antibodies raised against aspartate, glutamate, gamma-aminobutyrate (GABA), choline acetyltransferase (ChAT), and substance P (SP) have allowed the transmitter characterisation and distribution of cells of the lateralis medialis-nucleus suprageniculatus (LM-SG) complex to be made at the level of the light microscope. We have found that the intranuclear distributions of aspartate and glutamate differed substantially from that of GABA, as well as there being specific and, in some cases, major differences in the respective populations of cells labelled with all three amino-acid-sensitive antibodies. ChAT-labelled elements were disposed very similarly to acetylcholinesterase (AChE)-positive subregions of the nuclear complex, while SP labelling was comparatively weak, albeit present, throughout the region. These data provide an important first step towards the further understanding of the details of the neurochemical and functional identity of the LM-SG complex.

Acetylcholine↗

PubMed1991

Principal component analysis of various respiratory function tests: the relationship between factor score and severity of pulmonary circulatory disorder in chronic obstructive pulmonary disease.

The relationship between pulmonary haemodynamics and values of various respiratory function tests was studied in patients with mild chronic obstructive pulmonary disease (COPD) and the following results were obtained. (1) The value of mean pulmonary artery pressure (mPAP) at rest in COPD patients was slightly elevated to 19.4 mmHg on average compared with our control value of less than 18 mmHg. (2) Analysis of the data of 11 routine respiratory function tests in 88 COPD patients extracted two principal components: an index of the expiratory function and an index for overinflation of the lung. (3) In individual patients, mPAP expressed the severity of pulmonary circulatory disorder roughly inverse to the factor score of the first principal component (index of expiratory function) but not to that of the second principal component (overinflation of the lung). (4) Discriminant analysis was performed in all 88 COPD patients according to data from the 11 respiratory function tests. The probability of mPAP being above or below 18 mmHg was 18.2%. (5) The relationship between the predicted EPOI value and the factor score was similar to that between mPAP and the factor score. EPOI (exercise pulmonary artery pressure-oxygen consumption index) was calculated with the following equation: EPOI = (mPAPex#-mPAPrest)/[VO2ex-VO2rest)/BSA##). On the other hand, EPOIpred was calculated with the prediction equation obtained from multiple linear regression (dependent variable; EPOI, independent variable; respiratory function).

Adult↗

PubMed1991

[A study of methicillin-resistant Staphylococcus aureus (MRSA) infection in the urological field].

Clinical backgrounds of 35 patients with urogenital infection, from whom methicillin-resistant Staphylococcus aureus (MRSA) was isolated, were analyzed. Susceptibilities of these MRSA strains to various antimicrobial agents were also measured. Out of 35 MRSA strains, 29, 4 and 2 were isolated from urine, pus and sputum specimens, respectively, showing a definitely high isolation rate from urine. As for underlying diseases, 22 patients (62.8%), 11 (31.4%) and one each had a malignant tumor of the urinary tract or genital organ, prostatic hypertrophy, urolithiasis and vesicoureteral reflux, respectively. Patients aged at over 60 years numbered 20 (57%), and 32 patients (91.4%) were treated with some antimicrobial agent at the time of MRSA isolation. Out of 35 strains, 17 were isolated after total cystectomy with urinary diversion or transurethral surgery. As for the state of MRSA infection, 9 and 26 patients had single and polymicrobial infections, respectively, but none of patients had serious symptoms definitely thought to be caused by MRSA. On evaluation of susceptibilities of MRSA to various antimicrobial agents, the MRSA strains were found to be sensitive to minocycline, netilmicin and ofloxacin. From these results, MRSA strains isolated from patients treated in the field of urology were thought to rarely cause serious infectious symptoms, especially true for those isolated from the urine.

Adolescent↗

PubMed1991

Transient pulsus alternans induced by isosorbide dinitrate: echocardiographic and hemodynamic evidence of reduced venous return--a case report.

Transient pulsus alternans was induced by isosorbide dinitrate (ISDN) in a patient with postmyocarditis congestive heart failure under diuretic therapy. The severity and duration of pulsus alternans depended on the dose of ISDN. According to the echocardiographic and hemodynamic examinations, the superimposed preload reduction caused by ISDN combined with decreased blood volume owing to diuretic therapy most likely contributed to the development of pulsus alternans.

Adult↗

PubMed1991

Presence of the basement membrane component--heparan sulfate proteoglycan--in bovine lens capsules.

Heparan sulfate proteoglycan was extracted from bovine lens capsules by 0.45 M NaCl/2 M urea and purified using ion-exchange chromatography and gel filtration. The proteoglycan was found to consist of protein and carbohydrate in a ratio of 75 to 25. The estimated average molecular weight of the heparan sulfate proteoglycan eluted by 0.2 M NaCl on a diethylaminoethyl (DEAE)-cellulose column was 400 kilodaltons (kDa) and that of its glycosaminoglycan was 18.8 kDa. The amino acid composition of the proteoglycan was quite similar to that of the bovine glomelular basement membrane.

Amino Acids↗

PubMed1991

Elevation of intracellular cyclic adenosine 3',5'-monophosphate levels in macrophages activated with lipopolysaccharide for tumor cell killing.

The macrophage activation for tumor cytotoxicity with lipopolysaccharide (LPS) was remarkably inhibited by adding indomethacin (5 x 10(-6) M) or 10mM LiCl which is known to inhibit adenylate cyclase activity. The tumor cytotoxicity of macrophages inhibited with these agents was recovered by adding dibutyryl cyclic adenosine 3',5'-monophosphate (cAMP) (10(-4) or 10(-5) M) and furthermore tumor cell killing activity was augmented as compared with LPS-activated macrophage. Macrophages showed a 5 to 6 times increased intracellular cAMP concentration over the control within 30 min when incubated with LPS. However, the increased intracellular cAMP concentration was decreased by adding LiCl (10 mM). Thus, these findings indicate that there is an important relation between intracellular cAMP concentration and the mechanism of macrophage activation. One can then conclude that at least the initial enhancement of intracellular cAMP was important for tumor cell killing as a signal transmission in macrophage activated by LPS.

Animals↗