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H Kishida

Publications and source records attributed to H Kishida.

At least 127 records · Page 7Linked to original sources
PubMed1986

Molecular cloning of a xylanase gene from Streptomyces sp. No. 36a and its expression in streptomycetes.

The gene for an extracellular xylanase from Streptomyces sp. No. 36a was cloned into Streptomyces lividans TK21 using pIJ702 as a vector plasmid. The smallest DNA fragment encoding the xylanase gene and its possible promotor was determined to be a 1.04 kb Sph I-Sac I fragment by sub-cloning studies. This xylanase gene fragment was transferred into the pSK2 series of plasmids and introduced into Streptomyces kasugaensis G3 protoplasts. The cloned xylanase gene was expressed in both S. lividans TK21 and S. kasugaensis G3, and these clones produced and secreted high yields of xylanase into the culture medium. The xylanase production was not detected when a foreign DNA fragment was inserted into the Bcl I site locating in the xylanase gene fragment.

Cloning, Molecular↗
PubMed1985

The effects of mexiletine on action potential duration and its restitution in guinea pig ventricular muscles.

To clarify the mechanism of mexiletine-induced changes in action potential duration (APD), we studied the effects of mexiletine (2 micrograms/ml) on APD at 0 mV (APD0mV) and 90% (APD90%) repolarization and on restitution of premature responses in guinea pig ventricular muscle at three extracellular potassium concentrations [( K]0) and three stimulation rates using standard microelectrode techniques. The rates at which APD0mV and APD90% were shortened by mexiletine (S-APD0mV and S-APD90%) expressed as percent change from control were most pronounced at [K]0 = 5.4 mM. The percent changes at the three concentrations were 5.0 +/- 2.1% at a [K]0 of 2.7 mM, 6.0 +/- 3.2% at 5.4 mM and 1.8 +/- 1.2% at 10.0 mM for S-APD0mV and 2.0 +/- 1.9%, 4.7 +/- 2.0% and 1.3 +/- 1.5% for S-APD90% at the same concentrations, respectively. S-APD0mV and S-APD90% were more markedly affected when stimulated at a frequency of 1 Hz than when stimulated at 0.2 or 0.5 Hz. Mexiletine failed to produce any additional APD shortening beyond that produced by the introduction of tetrodotoxin (2.5 X 10(-6) M). Mexiletine and tetrodotoxin did not influence APD restitution that fitted a single exponential curve. We conclude that the shortening of APD by mexiletine results from inhibition of a tetrodotoxin-sensitive sodium current.

Action Potentials↗
PubMed1985

Prominent negative U wave in variant angina pectoris.

The extremely prominent negative U wave occasionally appears during a cardiac attack in variant angina pectoris. The clinical profile of the negative U wave was therefore studied in 80 patients with variant angina pectoris (VA) and 33 controls with resting angina pectoris (RA). The prominent negative U wave appeared in 55 of the patients with VA (68.8% of patients) and in 10 of the patients with RA (30.3%); thus, there was a significant difference in the appearance of the wave between the 2 groups of patients (p less than 0.001). The leads in which the negative U wave appeared were mostly consistent with those in which the ST segment was elevated. The negative U wave began to appear at about the time when ST-segment elevation began to improve; the wave then gradually became very prominent and then eventually disappeared. The patients with VA and also those with RA on whose ECGs the negative U wave appeared during exercise testing also had negative U waves during spontaneous episodes of angina. An investigation of the frequency of appearance of ST deviation and negative U waves during exercise testing, regardless of the type of angina pectoris, disclosed that the negative U wave appeared in 14 of 20 patients with ST-segment elevation (70% of patients), while the negative U wave appeared in only 52 of 519 patients with either no ST change or ST-segment depression (10.4%); thus, there was a significant difference in the appearance of the negative U wave between these 2 groups (p less than 0.001). Coronary cinearteriography failed to disclose any apparent difference between the appearance of the negative U wave and the presence of stenosis. The prognosis of VA and RA in patients with negative U waves was less favorable compared to those without negative U waves. In particular, we noted that of the 10 patients with RA associated with negative U waves, 4 died. Although the mechanism of the negative U wave is not yet known, we believe that the above findings contribute to its elucidation.

Adult↗
PubMed1985

Studies on the delayed neurotoxicity of organophosphorus compounds--(III).

TOCP (Tri-orthocresyl phosphate), an organophosphorus compound, has been implicated in producing neuropathy in the male S. D. rats. Repeated subcutaneous doses of TOCP (600 mg/kg) for up to 6 weeks produced ataxia, most striking at 50 days after final injection, followed by gradual recovery. Ultrastructurally, the internal structure of affected nerve fibers was primarily composed of altered smooth endoplasmic reticulum, tubular membrane system, and mitochondria, although myelin sheath was found to be essentially normal. In the histopathological examination, axonal and myelin degeneration was disclosed in the gracile nucleus and in the gracile fasciculus of the cords as well as in the sciatic nerves. The localization and degree of these changes were considered to be "dying back", showing systemic neuropathy. In addition, muscular lesion showed small group atrophy, corresponding to Type I fiber atrophy.

Animals↗
PubMed1985

[Basic and clinical studies on cefminox in obstetrics and gynecology].

Fundamental and clinical studies on cefminox (CMNX, MT-141), a new cephamycin antibiotic, were carried out and the results were as follows. After the intravenous one shot administration of 1 g CMNX to 17 cases, serum concentrations, tissue concentrations in pelvic organs and protein binding capacities in serum were measured. Blood concentrations ranged between 100-200 micrograms/immediately after the injection and declined gradually. Half-life (T1/2) was 75 minutes. Tissue concentrations were 30-70 micrograms/g (tissue weight) 10 minutes after injection and declined. Half-life was 90 minutes. The average serum protein binding rate was 66.3 +/- 8.4%. Correlation between tissue concentration (Y) and free serum concentration (X) was expressed as Y = 0.42 + 7.14X. Correlation coefficient (r) was 0.80 (r = 0.80). Correlation coefficient in serum concentrations between HPLC and bioassay was 0.83 and that in free concentration was 0.97. In clinical studies, CMNX was administered to 19 cases of obstetric and gynecological infections. The patients were constituted of 3 with puerperal endometritis, 3 with pyometra, 3 with pelvic peritonitis, 3 with parametritis, 3 with adnexitis, 2 with BARTHOLIN's abscess and 1 with retroperitoneal abscess and vulva abscess. Overall clinical efficacy was 89.5% (17/19). Bacteriologically 26 strains were isolated, 6 strains of E. coli, 4 strains of B. fragilis, 2 strains of P. anaerobius and P. asaccharolyticus and each one of E. faecalis, S. epidermidis, N. gonorrhoeae, S. marcescens, P. maltophilia, A. calcoaceticus, K. pneumoniae, P. mirabilis, H. influenzae, S. intermedius, E. lentum and F. varium. Twenty of these 24 strains were eliminated after the administration, K. pneumoniae was decreased, E. faecalis, S. marcescens and P. maltophilia remained unaffected. No side effects were observed but 1 case showed mild elevation of transaminases which normalized 1 week after CMNX was stopped.

Adolescent↗
PubMed1984

Studies on the delayed neurotoxicity of organophosphorus compounds--(II).

Delayed neurotoxicity experiment was carried out on an organophosphorus compound (TOCP) in hens. Fifteen hens, 1.9 kg of their average body weight and 20 months of age, were orally administered with TOCP in a dose of 400 mg/kg body weight. Two animals out of 15 were sacrificed after 7 days to examine alterations in the nervous system under electron microscope. On the remaining 13 animals, histopathological examinations were carried out after 35 days. During the course of the experiment, progressive neuropathy developed in the animals at 10 to 12 days after the exposure to TOCP. Examinations of the sciatic nerve under electron microscope revealed slight axonal degeneration while the myelin sheath was found to be rather intact. On the animals after the observations periods of 35 days, marked axonal and myelin degeneration was observed in the anterior and posterior funiculus, and in the spinocerebellar tracts of the spinal cord as well as in the cerebellar peduncle and in the white matter of the cerebellum associated with glial proliferation. The localization and degree of these changes were considered to be "Dying Back", showing systemic neuropathy. Moreover, the morphological alterations of the nerve cells were observed in the Purkinje cells, in the cerebellar nucleus, gracilis nucleus, and anterior horn cells of the lumbar spinal cords, characterized by loss of nerve cells and/or tigrolysis. Muscular lesions showed small group atrophy, corresponding to Type I fiber atrophy.

Animals↗
PubMed1983

Non-oat cell small cell carcinoma of the esophagus. Report of a case with ultrastructural observation.

A resected case of undifferentiated, non-oat cell type small cell carcinoma of the esophagus in a 78-year-old Japanese male is presented. Biopsy of a lower esophageal tumor that showed protrusions and centrally ulcerated features on esophageal roentgenograms, was initially misinterpreted as probable malignant lymphoma, because the absence of epithelial arrangement and the presence of abundant fine reticulin fibers encircling individual tumor cells. However, sections of the resected specimen disclosed minute foci consisting of nest formations of tumor cells suggesting an epithelial nature. Electron microscopy demonstrated immature round tumor cells, some of which showed occasional villous projections, desmosomal attachment devices, intracytoplasmic filaments resembling primitive tonofilaments. No neurosecretory granules as have been reported in oat-cell carcinoma of the esophagus were identified in the present case. The results suggest that this tumor is derived from the primitive cells of the esophageal mucosal epithelium or the duct of the esophageal glands. This tumor should be discriminated from oat-cell carcinoma on the basis of its histogenesis.

Aged↗
PubMed1983

[Clinical evaluation of BRL 25000 (clavulanic acid-amoxicillin) in the fields of obstetrics and gynecology].

BRL 25000 was administered to 37 cases with infections in the fields of obstetrics and gynecology, and the following results were obtained. The drug was administered to 17 cases with adnexitis, 13 cases with intrauterine infection and 7 cases with parametritis and/or inflammation of pelvic dead space, etc. The percentage of efficacy (excellent and good) was 74.3%. Of 7 cases where no therapeutic effect was obtained with other drugs, the percentage of efficacy was 57.1%. Antibacterial effect of BRL 25000 was studied in terms of percentage of eradication (including replacement) of clinical isolates. A high percentage of eradication (94.4% or 17/18) was obtained. Among all clinical isolates, 37.9% or 11/29 were beta-lactamase producing organisms. Eradication or replacement by BRL 25000 was noted in all these 9 strains, and BRL 25000 was proved to have a high efficacy also against penicillin or cephalosporin resistant organisms. No abnormality was noted in any patient in hematological, hepatic and renal function before and after administration of BRL 25000. As adverse reaction, diarrhea was found in 1 of 37 cases (2.7%), but it reduced after off-dose.

Adult↗
PubMed1983

[Clinical use of ticarcillin in the field of obstetrics and gynecology. Efficacy of ticarcillin in single administration and in combination therapy with S-sulfonated human immunoglobulin].

Single use of ticarcillin (TIPC, Monapen) was administered in 57 cases and combination therapy of TIPC and S-sulfonated human immunoglobulin (Venilon) was carried out in 23 patients who were either with severe infection, very old or in poor general conditions. The results obtained were as follows. Effective rate of single use of TIPC was 100% (3/3) in cases with infection, 50% (3/6) in cases with infection in which prior antibiotics therapy was poorly effective and 100% (48/48) in post operative cases. Effective rate of combination therapy of TIPC with S-sulfonated human immunoglobulin was 85.7% (6/7) in cases with infection, 71.4% (5/7) in cases with infection in which prior antibiotics therapy was poorly effective and 100% (9/9) in post operative cases. In laboratory findings, mild elevations of transaminase were recognized in 6 cases but restored to normal values without specific therapy. Side effect such as diarrhea, exanthema, fever, nausea and vomiting was not found in our cases.

Adult↗
PubMed1982

Negative U wave: a highly specific but poorly understood sign of heart disease.

A negative U wave is highly specific for the presence of heart disease and is associated with other electrocardiographic abnormalities in more than 90 percent of patients. The three most common conditions associated with a negative U wave are systemic hypertension, aortic and mitral regurgitation and ischemic heart disease. The U wave vector is directed opposite to the QRS axis in the horizontal plane in patients with both left and right ventricular hypertrophy. In patients with ischemic heart disease, the U wave vector tends to be directed away from the site of the akinetic or dyskinetic region. The change from a negative to an upright U wave after a reduction in blood pressure, renal transplantation, insertion of a valve prosthesis or a coronary arterial bypass graft procedure is associated with a decrease in the QRS amplitude but with no consistent changes in T wave polarity. The timing of the U wave apex is dependent on the duration of ventricular repolarization but not on the duration of the QRS complex. This finding and other electrocardiographic observations are explained better by the ventricular relaxation than by the Purkinje fiber repolarization theory of U wave genesis.

Aortic Valve Insufficiency↗
PubMed1982

Effects of calcium antagonists, especially nifedipine, on variant angina, resting angina, and unstable angina.

The effects of drugs were evaluated in 47 cases with variant angina (VA), 19 with resting angina showing ST depression (RA), and 84 with unstable angina (UA). In VA patients, calcium antagonists were effective in 87.1% of the cases, while other drugs were effective in 56.3%. The difference was statistically significant. In RA patients, calcium antagonists were effective in 80.0% of the cases and other drugs in 44.4%. Nifedipine was effective in all 5 cases with coronary stenosis of more than 75.0%. All cases of RA had multiple vessel disease and nifedipine was effective in 80.0% of the patients. Nifedipine was effective in 83.3% of VA cases showing ST elevation during an exercise test, and was particularly effective in all patients having attacks only at rest. The effects of nifedipine were confirmed in 83.3% of UA cases. These results indicate that calcium antagonists are effective in VA, RA, and UA.

Aged↗
PubMed1982

Chondromyxoid fibroma of bone. An electron microscopic observation.

A resected case of chondromyxoid fibroma of the right fibula in a 31-year-old male is presented. The histology was composed of characteristic lobular features of this tumor with abundant cartilaginous matrix. The ultrastructural study exhibited stellate, ovoid or elongated tumor cells with features of cartilage cells and abundant loose matrix with many fine filamentous structures. The nuclei were often of peculiarly indented contour and revealed thick fibrous lamina. The villous cell processes and intracytoplasmic fine filaments were prominent. No cells suggesting a fibroblast were recognized in this study. From the light microscopical and ultrastructural findings of this case, it is supported that this tumor might be derived from adult cartilage cells most likely related to the epiphyseal cartilage rather than fibroblasts.

Adult↗