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K Endou

Publications and source records attributed to K Endou.

At least 37 records · Page 2Linked to original sources
PubMed1993

Labile 50S ribosome from partial macrolide-resistant Staphylococcus aureus.

Staphylococcus aureus S704 and 8325MMT7 show constitutive resistance to macrolide antibiotics such as erythromycin (EM), oleandomycin, spiramycin, rosamicin and josamycin, except for tylosin, rokitamycin (RKM), and mycinamicin as well as lincosamide and streptogramin type B antibiotics (PM-resistance). Whenever 70S ribosomes from either of them were dissociated into 30S and 50S subunits in a 10-28%(W/W) linear sucrose gradient, the latter subunit was further cleaved into two small apparently equal particles (about 40S). RKM could no longer bind to either of the small particles. A prior exposure of 8325MMT7's 50S subunit to RKM (except EM) did not cause cleavage in any small particles. The largest component (M.W. 33.0kDa) of 50S ribosomal proteins was absent in at least the small particles. The first finding suggests that the lability of the 50S ribosome may be responsible for PM-resistance.

Ammonium Chloride↗
PubMed1993

Characteristics and localization of a determinant conferring partial macrolide resistance in Staphylococcus aureus carrying plasmid.

Staphylococcus aureus TPR-27, a clinically isolated strain, showed constitutive resistance to some macrolide antibiotics (erythromycin, oleandomycin, spiramycin, and josamycin), but susceptibility to the other macrolide (tylosin, rokitamycin, and mycinamicin), lincosamide, and streptogramin type B antibiotics (PM-resistance). The PM-resistant strain TPR-27 has carried for visible plasmids. Attempts to eliminate the resistant determinant in terms of ethidium bromide (about 3 micrograms/ml) did not succeed, and every trial to transduce the PM-resistant determinant into rec- mutant ISP105 using phage 80L2 propagated on strain TPR-27 also failed at the frequency of less than 1.1 x 10(-10) transductants per plaque-forming unit. These results suggest that the PM-resistance determinant is localized in chromosomal DNA.

Anti-Bacterial Agents↗
PubMed1993

[Inducible resistance to macrolide-lincosamide-streptogramin type B antibiotics in Bacillus licheniformis: common structures of macrolide antibiotics capable of inducing the resistance].

Whether or not resistance to macrolide-lincosamide-streptogramin type B antibiotics (MLS) can be induced by many macrolide antibiotics (Mac), was inquired in Bacillus licheniformis EMR. Resistance to MLS in the strain was induced by erythromycin, oleandomycin, clarithromycin, roxithromycin, narbomycin, picromycin, kujimycin A or B, mycinamicin I, or rosamicin. On the contrary, josamycin, spiramycin, tylosin, rokitamycin, midecamycin, and miokamycin as well as lincosamide and streptogramin type B antibiotics could not induce MLS-resistance. The results suggest that two common chemical residues of the inducer Mac, that is, 1) a single monosaccharide at C5 in the 14- and 16-membered lactone rings, and 2) one polar group such as dimethylamino or methoxyl at C3' in the sugar, are likely to be responsible for showing the activity of MLS-resistance inducer in Bacillus licheniformis EMR.

Anti-Bacterial Agents↗
PubMed1993

Implication of cohesive binding of a macrolide antibiotic, rokitamycin, to ribosomes from Staphylococcus aureus.

In a previous paper we reported that rokitamycin (RKM) which killed some types of RKM-susceptible staphylococci bound cohesively to ribosomes obtained from such bacteria whereas other macrolides such as erythromycin and josamycin, which are generally known to be bacteriostatic, bound to these ribosomes only reversibly. From this observation, we speculated that such cohesive binding of RKM to certain ribosomes probably resulted in cell killing (Endou, K. et al., FEMS Microbiology Letters, 72: 93-96, 1990). However, this speculation was based only on circumstantial evidence and we did not show directly that reversible binding of RKM to ribosomes from other strains would bring about bacteriostasis only. A clinically isolated strain. Staphylococcus aureus S704, was found to be susceptible to RKM, mycinamicin and tylosin as well as lincosamide and streptogramin type B antibiotics but not to other macrolides (erythromycin, josamycin, rosamicin, etc.). RKM showed bacteriostatic, but not bactericidal activity, on the strain. Determinant(s) responsible for the bacteriostatic phenotype was transferred into strain NCTC8325 using bacteriophage 80L2; the obtained transductant was referred to as strain 8325MMT7. The drug bound reversibly, not cohesively, to the ribosomes from both strains S704 and 8325MMT7, confirming our earlier hypothesis that rokitamycin can cause bacteriostasis or cell death depending upon whether it binds reversibly or cohesively to the ribosomes of a given strain.

Binding, Competitive↗
PubMed1992

[Single-dose treatment of tosufloxacin (TFLX) for acute uncomplicated cystitis].

The effectiveness of a single 300-mg dose of tosufloxacin and of 3-day treatment with tosufloxacin (300 mg daily) were compared in a prospective trial in order to clarify the cost-effectiveness of tosufloxacin for acute uncomplicated cystitis. Fifty female patients (25 patients of each group) with acute uncomplicated cystitis received one of these treatment regimens, and the clinical data and follow-up culture results were analyzed. The effectiveness rates of single-dose treatment and 3-day treatment after 3 days were 100% and 96%, respectively. The recurrence rates of single-dose treatment and 3-day treatment after 14 or 28 days were 0% (0/13 patients) and 15% (2/13 patients), respectively. There was no significant difference in the effectiveness rate and the recurrence rate between these two groups, statistically. All isolated strains were eliminated in both regimens. From these results, it is suggested that single-dose treatment of tosufloxacin is effective enough for acute uncomplicated cystitis.

4-Quinolones↗
PubMed1992

Inducible resistance to a 16-membered macrolide, mycinamicin, in Staphylococcus aureus resistant to 14-membered macrolides and streptogramin B antibiotics.

Staphylococcus aureus 8325(pEP2104), a transductant derived from S. aureus PM2104 isolated clinically in Hungary (L. Janosi, and E. Ban, Acta Microbiol. Acad. Sci. Hung., 29: 187-200, 1982), exhibited an inducible resistance to the 14-membered macrolides [erythromycin (EM) and oleandomycin (OL)] and streptogramin B (MKM-B) antibiotics, but not to the 16-membered macrolides and lincosamides. This resistance was referred to as PMS-resistance phenotype (L. Jánosi, Y. Nakajima, and H. Hashimoto, Microbiol. Immunol., 34: 723-735, 1990). In addition to EM, OL, and MKM-B, however, the strain was recently and first observed to have inducible resistance to mycinamicin, a 16-membered ring macrolide. Thereby, we propose that the reference stated just above as PMS-resistance has to be extended to such 16-membered macrolides as mycinamicin. An optimum concentration of erythromycin or oleandomycin for induction of PMS-resistance was 1.35 mu g/ml in the strain 8325(pEP2104). The concentration was about 30 times as great as that (0.05 mu g/ml) required for induction of well-known co-resistance to macrolide-lincosamide-streptogramin B antibiotics in S. aureus ISP447.

Anti-Bacterial Agents↗
PubMed1990

Adhesive binding of rokitamycin to Staphylococcus aureus ribosomes.

Rokitamycin (RKM), a 3"-O-propionyl derivative of leucomycin A5, is bactericidal against staphylococci near the minimum inhibitory concentrations. RKM bound to ribosomes before-hand is only slightly displaced by erythromycin or josamycin, or even by RKM itself. The adhesive binding of the RKM-ribosome complex might prove to be the lethal event for susceptible staphylococci.

Erythromycin↗
PubMed1990

Localization of a determinant mediating partial macrolide resistance in Staphylococcus aureus.

Four out of more than 8,200 Staphylococcus aureus strains isolated in Japan between 1961 and 1980 were constitutively resistant to a variety of macrolide antibiotics except tylosin and rokitamycin, but susceptible to lincosamide and streptogramin type B antibiotics (PM). The data obtained by agarose gel electrophoresis, CsCl-ethidium bromide density gradient analysis, diagnosis with ATP-dependent deoxyribonuclease, and a test transducing into a rec- mutant with phage 80L2 propagated on PM-resistant S. aureus all suggested that the determinant for the PM-resistance is located in chromosome.

Anti-Bacterial Agents↗
PubMed1990

Greatly improved activity of staphylococcal ribosomes in polyadenylate directed polylysine synthesis: as an assay system for investigating their sensitivity to macrolide antibiotics.

In polyadenylate directed polylysine synthesis, homologously cell-free extracts containing ribosomes and S-100 (105,000 x g supernatant) from staphylococcal cells have less than one-half (one-tenth, when the extracts were stored at -80 degrees C within a few weeks) of the activity of the extracts from Escherichia coli Q13. The present study is concerned with further improving the activity of staphylococcal ribosomes. The polylysine-synthesizing ability by staphylococcal ribosomes increased up to about two times as much as that by E. coli Q13 ribosomes, when S-100 from E. coli Q13 was mixed with staphylococcal ribosomes which had been washed with a high salt HEPES buffer containing 10 mM HEPES, 1 mM EGTA, 16 mM magnesium acetate, 1.0 M ammonium chloride and 0.1 mM dithiothreitol (pH7.6). Polylysine synthesis by the heterologous extracts has an advantage over polyuridylate-directed polyphenylalanine synthesis in the analysis of ribosome sensitivity for macrolide antibiotics, especially erythromycin.

Anti-Bacterial Agents↗
PubMed1989

[A comparative study between cefodizime (CDZM) and cefotaxime (CTX) in respiratory tract infections].

The clinical efficacy and safety of Cefodizime (CDZM), a new cephem antibiotic, was objectively compared with that of Cefotaxime (CTX) in patients with respiratory infections under a well-controlled comparative study. Patients were administered CDZM or CTX by drip infusion b.i.d. for 14 days in principle at a daily dose of two grams. The parameters assessed were clinical efficacy, safety and clinical usefulness. The following results were obtained: 1. On the basis of committee judgement the clinical efficacy rate was 78.1% (125/160) for the CDZM group, 82.7% (124/150) for the CTX group, and no significant difference was observed between the two drug groups. On the other hand, on the basis of judgement by physicians in charge, the clinical efficacy rate was 83.1% (133/160) for the CDZM group, 83.9% (125/149) for the CTX group, and no significant difference was observed between the two groups. 2. The corresponding figures for patients with pneumonia and pulmonary suppuration were 82.4% (70/85) for the CDZM group, 79.7% (59/74) for the CTX group and no significant difference was observed according to the committee judgement. The judgement by physicians in charge also revealed 83.5% (71/85) for the CDZM group and 82.2% (60/73) for the CTX group. No significant difference was noted between the two groups. While, the committee judgement for the clinical efficacy in patients with chronic respiratory tract infections showed 73.3% (55/75) for the CDZM group, 85.5% (65/76) for the CTX group, and no significant difference was observed between the two drug groups. The corresponding figures were 82.7% (62/75) for the CDZM group, 85.5% (65/76) for the CTX group, and no significant difference was observed between the two drug groups on the judgement by physicians in charge. Furthermore, the clinical efficacy of both drugs on chronic respiratory tract infections was assessed according to "Criteria for Evaluation of Clinical Efficacy of Chemotherapeutics on Chronic Respiratory Tract Infection". It was 76.8% (53/69) for the CDZM group, 76.3% (58/76) for the CTX group, and no significant difference was observed between the two groups. 3. The bacteriological eradication rate of causative pathogens was 92.4% out of 66 patients treated with CDZM and 95.5% out of 67 patients treated with CTX in whom judgement was possible. No significant difference was observed between the two drug groups. 4. The adverse reactions occurred in 4 (2.2%) patients for the CDZM group and 8 (4.5%) patients for the CTX group respectively, with no significant inter-group difference in frequency of these reactions for all cases.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗
PubMed1989

[A new computed tomography method for quantitative analysis of abdominal aortic atherosclerosis].

Clinical evaluation of aortic atherosclerosis has been most commonly performed by visual analysis of aortic calcification on conventional radiographs or X-ray CT. However, precise evaluation of the degree of calcification or mild changes with increasing age can be difficult by these methods of visual analysis. A new quantitative method of evaluating the abdominal aortic atherosclerosis using CT is reported. Target CT scans of the abdominal aorta were performed at the level of the 1st, 3rd and 4th lumbar vertebrae. Two circular regions of interest (ROI) were selected along the outer margin and inner margin of the abdominal aortic wall on CT images, since it was difficult to precisely trace the aortic wall. Histograms of CT value for each pixel were made from two ROIs. A histogram at the ROI of the outer margin was depicted using class values over the maximum CT value in histogram at the ROI of inner margin which indicated flowing blood. A sum of products of the value in each class by the number in that class was divided by the aortic diameter. The value thus obtained was defined as the atherosclerotic index (S.I.). Forty-five cases were studied with this method. Six cases were excluded because of artifacts. The remaining 39 cases (16 males, 23 females) were analyzed. S.I. increased with aging and was higher in men than in women. However, it increased more rapidly in women (8.68/year) than in men (2.73/year). Because this new method employed the CT value, it is more objectively quantitative than previous methods of visual analysis in evaluating abdominal aortic atherosclerosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1987

Comparison of the effects of calcium channel blockers and antiarrhythmic drugs on digitalis-induced oscillatory afterpotentials on canine Purkinje fiber.

We studied the effects of Ca channel blockers and 3 antiarrhythmic drugs on the digitalis-induced oscillatory afterpotential (OAP). The OAP was observed in Purkinje fibers stimulated by pulse trains, with cycle lengths ranging from 1,000 to 300 msec. The Ca channel blockers verapamil, diltiazem and nifedipine (2.0 x 10(-6) M) depressed OAP significantly and abolished triggered activity. Verapamil was more effective than diltiazem. However, nicardipine and nitrendipine (2.0 x 10(-6) M) had no depressant effects on OAP or triggered activity. The antiarrhythmic drugs procainamide (1.0 x 10(-4) M), mexiletine (1.0 x 10(-5) M) and propranolol (1.0 x 10(-4) M) depressed both OAP and triggered activity. There were no significant differences in the depressant effects between the Ca2+ antagonists (except for nitrendipine and nicardipine) and the other antiarrhythmic drugs. The OAP coupling interval was prolonged by verapamil, diltiazem, propranolol, procainamide and mexiletine. Although the APD50 was shortened by verapamil, diltiazem and nifedipine, it was prolonged by propranolol. It is concluded that nifedipine, verapamil, diltiazem, procainamide, mexiletine and propranolol may be effective for digitalis-related arrhythmia.

Animals↗
PubMed1986

[Biliary excretion and clinical evaluation of cefoperazone in the biliary tract infections].

Biliary excretion Cefoperazone (CPZ) in a dose of 1 g was intravenously injected to each of 13 cases with obstructive jaundice. Entire bile was collected through percutaneous transhepatic cholangiodrainage (PTCD) catheter in every 1 hour for 6 hours. The mean concentration of CPZ in serum was 112.1 +/- 17.8 micrograms/ml (mean +/- S.E.) at 1 hour and 55.1 +/- 19.2 micrograms/ml at 6 hours after injection. The mean recovery of CPZ in bile within 6 hours was 1.13 +/- 0.60%. Average CPZ concentrations in bile were 64.0 +/- 45.8 micrograms/ml in the 1 hour fraction, 142.7 +/- 78.4 micrograms/ml in the 2 hours fraction and 72.2 +/- 34.0 micrograms/ml in the 6 hours fraction. Biliary excretion of CPZ was low in cases where the serum concentration of total bilirubin was high, but maximum CPZ level in bile in patients with higher serum bilirubin concentrations than 30 mg/dl was still more than 3 micrograms/ml. Clinical evaluation. CPZ was administered to 43 patients with biliary tract infections. The efficacy ratio was 88.4% (excellent and good cases) in all cases, and especially high in cases with cholecystolithiasis. But no difference in efficacy ratio was observed among cases with cholecystolithiasis, choledocholithiasis without gallstone and cases subjected to PTCD. In 10 patients examined by ultrasonography, 8 cases showed reduced diameters of gallbladder. No adverse effect of CPZ was noted in any cases. These results suggest that a fairly large portion of CPZ was excreted through bile and that CPZ is a very useful drug for the treatment of biliary tract infections.

Adult↗
PubMed1980

Arrhythmia diagnosis by the IBM electrocardiogram analysis program.

A comparative study was made between rhythm diagnosis by computer using the IBM ECG program (Bonner-I), and diagnosis by a physician, 2434 electrocardiograms (ECGs) recorded in Kitasato University Hospital from July to August 1978 were used. Of the 2434 cases the physician made a diagnosis of sinus rhythm in 2185 and of abnormal (other than sinus) rhythm in 249. Among theformer, 32 cases were erroneously classified into abnormal groups by the computer (false positive), and in 30 out of the latter 249 cases, the computer failed to detect abnormalities (false negative). In the remaining 219 cases, 33 of 57 cases of sinus rhythm with VPCs, 19 of 41 sinus rhythm with SVPCs, and 62 of 64 atrial fibrillation were correctly diagnosed by the computer. In 27 out of the 219 cases "undetermined rhythm" was printed out after an unsuccessful dominant rhythm determination by the computer. Cases of artificial pacemaker were not recognized by the computer, but were distributed into 7 classification categories. We were of the opinion that if the computer program had utilized the information on the duration of QRS complexes these cases could have been correctly classified. We repeated ECG sampling and analysis in the cases of complicated arrhythmias, because more valuable information was often supplied by the computer after successive ECG recording. From these results we concluded that the usefulness of the IBM ecg program was confirmed concerning the recognition of sinus rhythm, whereas the detection and identification of complex rhythm disturbances by the computer program was still in need of improvement.

Arrhythmias, Cardiac↗