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Biomedical subjects

S Watabe

Publications and source records attributed to S Watabe.

At least 127 records · Page 7Linked to original sources
PubMed1989

Calcium-independent activation of contractile apparatus in smooth muscle by calyculin-A.

Calyculin-A (CL-A), a novel marine toxin isolated from Discodermia calyx, caused contraction in the smooth muscle of guinea pig taenia ceci and rat aorta in the presence or absence (with 1 mM ethylene glycol bis(beta-aminoethyl ether)-N,N'-tetraacetic acid) of external Ca++ at concentrations ranging from 1 X 10(-8) to 1 X 10(-6) M. In the presence of external Ca++, the contraction induced by CL-A was accompanied by an increase in the cytosolic free Ca++ concentration [( Ca++]cyt) as measured by the fluorescence indicator fura-2. Verapamil (3 X 10(-6) M) inhibited the increase in [Ca++]cyt, but not tension development caused by CL-A. In the absence of external Ca++, CL-A still caused contraction without changing [Ca++]cyt. Thus, from studies with intact smooth muscle it was demonstrated that, in the absence of external Ca++, CL-A can induce a contraction that was not accompanied by an increase in [Ca++]cyt. In permeabilized taenia, CL-A caused contraction in the absence of Ca++ (with 2 mM ethylene glycol bis(beta-aminoethyl ether)N,N'-tetraacetic acid) at concentrations similar to those required to contract intact tissue. This contraction was inhibited by the nonselective kinase inhibitors such as amiloride (1 X 10(-3) M) and K-252a (2 X 10(-5) M). Low concentrations of Ca++ (approximately 1 X 10(-6) M) augmented the CL-A-induced contraction in the permeabilized taenia. In native actomyosin prepared from chicken gizzard CL-A induced phosphorylation of the 20 kDa myosin light chain (MLC) in the absence of Ca++.(ABSTRACT TRUNCATED AT 250 WORDS)

2',3'-Cyclic-Nucleotide Phosphodiesterases↗
PubMed1989

[Electrophysiological study on the atrophied pectoralis major muscle after modified radical mastectomy].

In order to clarify the cause of the atrophy of the pectoral muscles after modified radical mastectomy, twenty patients who had had the operation at Nagasaki Chuo National Hospital 40 days to 2 years prior to this study, were investigated by electromyography. Of 20 subjects, 11 had the operation to preserve the pectoralis major muscle and 9 had the operation to preserve both the pectoralis major and minor muscles. The results were as follows: 1) Electromyography revealed some damages to the pectoral nerves in 16 cases of 20 (80%). In 12 cases, development of fibrillation potentials was observed at rest, while motor unit potentials disappeared during voluntary contraction. These findings suggest the damage to the nerves including neutrotomy. 2) The regions with macroscopic muscular atrophy remarkably coincided with those with neurogenic changes on electromyography. This suggests that the atrophy of the pectoralis major after modified radical mastectomy might be mainly caused by the damage to the pectoral nerves. 3) The mastectomy preserving only the pectoralis major tends to cause damage to nerves innervating the sternocostal part of the pectoralis major more frequently than the mastectomy preserving both the pectoralis major and minor muscles. The abdominal part was frequently damaged irrespective of the types of the operation.

Action Potentials↗
PubMed1988

Diagnostic value of Q waves outside standard precordial lead points in left anterior myocardial infarction undetectable by standard 12-lead electrocardiogram.

Body surface potential maps were recorded for 52 patients with solitary anterior myocardial infarction and 57 normal subjects. All patients had pure anterior wall asynergy on a left ventriculogram but no diagnostic Q wave on the standard 12-lead electrocardiogram. Q wave (greater than 30 msec) distributions on the body surface of the patients and normals were compared. The frequency of Q waves in the area above V1-V2 and in the right middle chest was significantly higher in patients than in normals. The sensitivity of Q waves for asynergy in leads from both these areas was 19-60%. The positive predictive value was 67-94%. The frequency of Q waves was significantly higher in severe asynergy than in mild asynergy. A combination of two selected unipolar leads from these areas yielded a sensitivity and specificity of 33% and 95%, respectively. With a combination of three leads, these values were 42% and 93% and with four leads 48% and 88%, respectively. The results indicate that several unipolar leads from the area above V1-V2 and from the right middle chest in addition to the standard 12-lead electrocardiogram may improve the electrocardiographic diagnostic accuracy of myocardial infarction.

Electrocardiography↗
PubMed1988

Properties of two toxins isolated from the blue-green alga Microcystis aeruginosa.

Attempts were made to characterize the two toxins (P-1 and P-2) isolated from the blue-green alga Microcystis aeruginosa, by amino acid analysis, mass spectrometry, 1H- and 13C-NMR. P-2, the major toxin, had a molecular weight of 1044, and consisted of one molecule each of beta-methylaspartic acid, D-Glu, D-Ala, L-Arg, L-Tyr, N-methyldehydroalanine, and 3-amino-9-methoxy-2,6,8-trimethyl-10-phenyldeca-4,6-dienoic acid (Adda). P-1, with a molecular weight of 994, appeared to have almost the same composition except that it contained L-Leu instead of L-Tyr in P-2. Mass spectrometric studies, along with a negative ninhydrin reaction, indicated that each toxin was a cyclic peptide. P-2 showed an LD99 of 70 micrograms/kg mice when injected i.p. and [alpha]D24 of -72.42 degrees (c = 0.095 in methanol), and was decomposed at around 218 degrees C.

Amino Acids↗
PubMed1988

Physicochemical and immunological properties of myosin light chains from the ordinary muscle of marine teleost fishes.

1. Myosin light chains (A1, A2 and DTNB light chain) were isolated from the ordinary muscle of six marine fishes and the physicochemical and immunological properties were examined. 2. All the isolated light chains were rich in aspartic and glutamic acids, alanine and lysine, but poor in histidine and tyrosine. The contents of alanine, proline and lysine were generally higher in A1 than in A2. Between closely related species such as skipjack and bonito, the amino acid profiles of corresponding light chains were very similar to each other. 3. Structural similarity and difference of A1 light chain were further demonstrated immunologically using anti-A1 antiserum. Precipitation lines were fused with each other among closely related species, whereas strong spurs were observed among phylogenetically distinct species.

Amino Acids↗
PubMed1988

Sites of origin of ventricular premature beats in patients with and without cardiovascular disease evaluated by body surface mapping.

The site of origin of ventricular premature beats (VPBs) was estimated by QRS maps and its distribution in two patient groups was studied. VPB origin was determined by comparing the body surface map of VPBs with that during electrical stimuli applied at various sites of the ventricle. Subjects were 100 patients without obvious underlying cardiovascular disease (Group N) and 289 patients with various heart diseases (Group D). Nine sites of origin of VPB were identified. In group N, VPBs of right ventricular origin were noted in 69%, those of left ventricular origin in 6%. There was a relatively high incidence of VPBs with foci estimated to be the divisions of the left bundle branch, and the age of patients with these VPBs was young. In Group D, VPBs of left ventricular origin showed a higher incidence (34.6%) and those of right ventricular origin a lower incidence (41.2%) than those in group N. The data suggest that VPBs originating from the apex and base of the ventricle strongly indicate the presence of basic heart disease and that VPBs originating in or near the divisions of the left bundle branch in younger subjects do not necessarily indicate cardiac disease.

Adolescent↗
PubMed1988

New diagnostic evidence on the T wave map indicating involved coronary artery in patients with angina pectoris.

To define the clinical significance of T wave map changes in patients with angina at rest, body surface isopotential T distributions were obtained in 48 patients with single-vessel disease (left anterior descending artery, 34; right coronary artery, eight; left circumflex artery, six) documented angiographically and were compared with those in 120 healthy subjects and those in 19 patients with left ventricular overload whose electrocardiograms showed negative T waves accompanied by an increase in R wave amplitude in left precordial leads. The T wave map abnormalities were observed in 24 of 48 patients (50%) with angina and were classified into three types: (1) type I (18 patients, 37.5%) was characterized by a segmental negative potential in the positive area located at the left thorax and the minimum at the peak of T wave positioned in the upper portion of the left anterior chest, (2) type II (three patients, 6.3%) was characterized by a negative potential with a minimum in the inferior thorax and an indentation of negative potential at the lower margin of the positive potential located over the upper thorax, and (3) type III (three patients, 6.3%) was characterized by a negative potential with a minimum at the back throughout the period of T wave. All patients showing T wave map abnormalities of type I had a significant stenosis of the left anterior descending artery. Likewise, all patients with type II or III had single-vessel disease of the right coronary or left circumflex artery, respectively. All types of T wave map changes observed in patients with angina were different from those in patients with left ventricular overload, whose maps showed the generalized negative potential at the inferior thorax and the left back and the minima clustered at the precordium. In seven patients with lesions of the left anterior descending artery, T wave map abnormalities of type I recovered to normal after successful percutaneous transluminal coronary angioplasty. The behavior of the negative potential and its extrema on the T wave map, which was not available from routine electrocardiography, was indicative of the involved coronary artery and probably of its associated ischemic area in one-half of our patients with angina pectoris.

Adult↗
PubMed1988

[Portal blood level of carcinoembryonic antigen (CEA) in colorectal cancer: correlation between tumor CEA content and immunohistochemical staining].

From tumors obtained from 87 patients with colorectal cancer during operation, portal blood levels of carcinoembryonic antigen (CEA) in drainage vein were measured and evaluated, according to the disease stage and histology, in comparison with cancerous tissue CEA in the extracts of surgical specimens and immunohistochemical analyses graded according to localization patterns and immunoreactivity; thereby trying to clarify a mechanism for the elevation of peripheral CEA levels. Mean value of portal CEA was higher than that of peripheral CEA at each stage of diseases, with a marked elevation by operative procedures. Although no significant correlation was observed between CEA contents of cancerous tissue (ng/g wet weight) and peripheral CEA levels, a close correlation was observed between portal CEA levels and cancerous CEA contents. A high CEA value was noted in moderately differentiated adenocarcinoma, according to cell differentiation (p less than 0.05). High portal CEA level was recognized in those with stain of cytoplasm and stroma, besides cancerous tissue CEA content, by means of immunopathochemical localization pattern, but a more significantly elevated CEA level was observed in those with the cancer pathologically infiltrating over muscle layers. The present study suggests that the route of CEA transfer from tumor to portal blood can be an important contributing factor to the control of peripheral CEA level.

Carcinoembryonic Antigen↗
PubMed1987

Distribution of tritiated tetrodotoxin administered intraperitoneally to pufferfish.

Tetrodotoxin was recoil-tritiated by the 3He(n,p)3H reaction and purified by gel filtration. The [3H]tetrodotoxin gave only one spot in both cellulose acetate strip electrophoresis and thin layer chromatography. The specific toxicity of tetrodotoxin did not decrease during the recoil tritiation and the [3H]tetrodotoxin showed a specific radioactivity of 25 x 10(-6) Ci/mmole. In spite of the low specific radioactivity, the [3H]tetrodotoxin was able to be used to investigate the anatomical distribution of tetrodotoxin in pufferfish. When intraperitoneally injected into 'torafugu' puffer, [3H]tetrodotoxin accumulated in most tissues, the level being highest in the skin, followed by the liver, intestines and muscle. With time, the [3H]tetrodotoxin radioactivity level in the injected pufferfish decreased in most tissues, except for skin and gallbladder. Based on these results, the metabolism of tetrodotoxin in pufferfish is discussed.

Animals↗
PubMed1987

[Eigenvector analysis in body surface potential maps for evaluating right ventricular hypertrophy in primary pulmonary hypertension].

This study related the eigenvectors derived from the QRS complex in body surface isopotential maps of normal subjects to regional myocardial excitation, with special emphasis on the right ventricle. The subjects consisted of 120 normal healthy adults and eight patients with primary pulmonary hypertension and right ventricular hypertrophy (PPH). According to the Karhunen-Loève theory, eigenvectors were derived from the normal group and the eigenvector coefficient of each subject was obtained against time for the first three components. The cumulative proportion of the first three eigenvectors was 90.3% in normals and 80.2% in PPH. The first eigenvector had a peak of eigenvector coefficients early in the QRS and had a bottom late in the QRS. The peak of the second was in the middle of the QRS. The coefficients of the third eigenvector were low compared to the former two eigenvectors, and had no characteristic time pattern. PPH had a similar time pattern of coefficients in the first eigenvector, reduced coefficients in the second, and a definite peak in the mid-QRS in the third. The average eigenvector coefficient of the third eigenvector in PPH was significantly higher than those in normal subjects (p less than 0.01). We conclude that the third eignevector derived from normal subjects strongly reflects right ventricular excitation.

Adult↗
PubMed1987

[Two cases of surgically treated triple cancer].

Two cases of surgically treated triple cancer are reported. Case 1: Three tumors, one in the lung, one in the stomach, and one in the colon of a 74-year-old man were diagnosed preoperatively. First a subtotal gastrectomy and transverse colectomy were performed and, second 27 days later, a lobectomy of the lower left lung. Pathologically, each tumor proved to be a primary sion. Case 2: A 70-year-old woman, treated surgically for left breast cancer 5 years ago, was found to have anemia. Gastric endoscopy showed a cancer in the antrum. A subtotal gastrectomy was performed. Intraoperatively another tumor in the cecum was found and a right hemicolectomy was also performed. Pathologically each tumor was a primary lesion.

Adenocarcinoma↗
PubMed1986

Effects of various tricyclic antidepressants on amine uptake.

A comparative study of the ability to block the amine pump was carried out on tricyclic antidepressants including dothiepin and northiaden in vivo. Dothiepin was found to prevent the 6-OHDA-induced depletion of cardiac noradrenaline but not the PCA-induced depletion of intracerebral serotonin. Northiaden, an active metabolite of dothiepin, also possessed the same ability with a greater potency than the parent drug. Neither compound affected the biosynthesis of catecholamines and indoleamine. However, neither dothiepin nor northiaden affected 5-HT uptake, as was also observed with imipramine and amitriptyline. These results suggest that the clinical efficacy of dothiepin may be due to inhibition of the amine pump, especially of the catecholamine uptake mechanism, which is qualitatively the same as for imipramine and amitriptyline.

Amitriptyline↗