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S Nishida

Publications and source records attributed to S Nishida.

At least 379 records · Page 21Linked to original sources
PubMed1982

Antimicrobial susceptibility of Clostridium difficile from different sources.

A total of 79 Clostridium difficile strains from healthy young and elderly adults, elderly patients without gastrointestinal disease, elderly patients receiving antibiotics without gastrointestinal complications, and elderly patients with antibiotic-associated diarrhea or pseudomembranous colitis were tested for their susceptibilities to 24 antimicrobial agents. All of the 79 strains were inhibited by low concentrations of rifampicin, metronidazole, fusidic acid, vancomycin, ampicillin, and penicillin G. Strains were highly resistant to aminoglycosides, trimethoprim, sulfamethoxazole, nalidixic acid, and cycloserine and often resistant to neomycin, cefoxitin, and cefalexin. Wide variations in the susceptibility of C. difficile strains to erythromycin, clindamycin, lincomycin, chloramphenicol, and tetracycline were found. Strains resistant to erythromycin, clindamycin, and lincomycin were more frequently found among strains isolated from elderly adults than those isolated from young adults, with particularly high frequency among strains isolated from elderly patients receiving antibiotics. None of the 23 strains isolated from healthy young adults was resistant to chloramphenicol. All of the 14 strains resistant to erythromycin, clindamycin, lincomycin, and chloramphenicol were sensitive to tetracycline and all of the 15 strains resistant to erythromycin, clindamycin, lincomycin, and tetracycline were sensitive to chloramphenicol. Only one out of 19 tetracycline, resistant strains was highly toxigenic, whereas 42 (70%) of the 60 sensitive strains were highly toxigenic.

Adult↗
PubMed1982

Carbohydrate fermentation by Clostridium difficile.

Biochemical properties of Clostridium difficile were reinvestigated for the practical identification of the organism in clinical laboratories. Bacterial growth in 2% proteose peptone medium supplemented with 0.01% L-cysteine.HCl and 0.1% agar supported sufficient growth to read the fermentation results just as well as did pre-reduced anaerobically sterilized medium. Incubation for 2 days was long enough for determining the ability to ferment fructose, glucose, mannitol, mannose, melezitose, and sorbitol. All of the 82 strains liquefied 2% but not 10% gelatin. The significance of mannitol fermentation and gelatin liquefaction is stressed since C. difficile is the only species fermenting mannitol among the gelatin-liquefying species of clostridia having subterminal spores.

Carbohydrate Metabolism↗
PubMed1982

Variable sugar fermentation by clostridia.

Forty-two sugar fermentation characteristics recorded as "d" in the 8th edition of Bergey's Manual of Determinative Bacteriology were reinvestigated by using eight different peptone media and 205 strains of nine species of pathogenic clostridia. In the absence of sugar, the final pH of 7-day cultures in the basal medium varied widely depending on the peptone employed, the species tested, and even the strain of the species. In the presence of sugar, the final pH of 7-day cultures was markedly influenced by these factors. Since the sugars with reactions recorded as "d" were weakly fermented and, consequently, the fermentation reactions were easily affected by cultural variations resulting in strain instability, we employed the pH difference method (delta pH method) in which the pH difference of 0.5 between cultures with and without sugar was used as the critical level. Thirty-six (86%) of the 42 sugar reactions recorded as "d" were sorted into "+" or "-" by the delta pH method. Six sugars, however, still remained as "d" because of their extremely weak fermentation characters. The use of the delta pH method in any peptone medium not only minimizes incorrect evaluation but also can provide some distinct criteria for identification of clostridia.

Carbohydrate Metabolism↗
PubMed1982

Effect of clindamycin on cytotoxin production by Clostridium difficile.

A total of 80 strains of Clostridium difficile, 33 toxigenic and 11 nontoxigenic clindamycin (CLDM)-sensitive (MIC less than 12.5 micrograms/ml), and 23 toxigenic and 13 nontoxigenic CLDM-resistant (MIC 200 to 6,400 micrograms/ml) were tested for cytotoxin production in the presence of CLDM. None of the 24 nontoxigenic strains produced cytotoxin regardless of the presence of CLDM and only six out of the 56 toxigenic strains showed 16- to 64-fold higher levels of cytotoxic activity in the presence of CLDM at the concentrations of 1/2 to 1/32 of the MIC than in the absence of CLDM; all of the six strains were CLDM sensitive. Further studies revealed that addition of CLDM to the culture caused enhanced cytotoxin synthesis, and that the maximum production of cytotoxin was obtained when CLDM was added to the medium at the time of inoculation or of the ensuing early logarithmic phase. Also, the influence of other antibiotics on the effect of CLDM was examined. Addition of metronidazole, vancomycin, chloramphenicol, cephaloridine, or penicillin, which induced cytotoxin to medium containing CLDM did not increase the effect of CLDM any further. Addition of CLDM to medium containing tetracycline, which inhibited cytotoxin production, induced cytotoxin production but not fully.

Anti-Bacterial Agents↗
PubMed1982

The discrepancy between plasma 11-deoxycortisol and ACTH concentrations in a single dose metyrapone test in normal men.

A single dose methyrapone test (MTP test) was carried out on 6 normal men by administering 1.0 g of metyrapone at 08.00-09.00 h with and without dexamethasone (DXM-MTP test) pre-treatment. Plasma 11-deoxycortisol, pregnenolone, ACTH and cortisol were measured before administration of the drug, and at hourly intervals for 6 h. In the MTP test, 11-deoxycortisol increased significantly at 1 h with a peak at 5 h, whereas significant increases in pregnenolone and ACTH were not seen until 3 h. There was a definite decrease in the cortisol level at 1 h with the lowest level measured at 2 h. Thus, a time discrepancy between plasma 11-deoxycortisol and ACTH concentrations was observed. The increase in 11-deoxycortisol after metyrapone should be divided into two phases: the increase in phase II (after 3 h) is due to the pituitary ACTH reserve, and that in phase I (the first 2 h) is due to some mechanism other than the pituitary ACTH reserve. The increased amount of 11-dexoycortisol in phase II (218.1 nmol) occupied 60.5% of the total increased amount in phases I and II (360.6 nmol). The cortisol/(cortisol + 11-deoxycortisol) ratio reached its lowest point 3 h after metyrapone treatment. This might be due to the initiation of an additional surge in 11-deoxycortisol by the ACTH reserve at 3 h.

17-Hydroxycorticosteroids↗
PubMed1982

[Seven-year follow-up studies on asymptomatic HBs Ag carriers].

This report covers 7-year follow-up studies on 35 HBs Ag carriers whose anti-HBc titer levels were 10 (log 2) or more and who had normal liver functions at the start of the studies, when 9 of them (25.7%) were HBe Ag positive, 24 (68.6%) anti-HBe positive and 2 (5.7%) negative to both. 1. There was no significant difference in the incidence of abnormal SGPT levels as a whole between HBe Ag positives and anti-HBe positives. But abnormally high SGPT levels of 100 KU or more were observed at a higher percentage among HBe Ag positives (4/9. 44.4%) than among anti-HBe positives (1/24. 4.2%. p less than 0.02). 2. Based on the results of the 7-year studies, all cases were classified into six clinical stages. HBe Ag positives were divided into three groups by the stage with different SGPT levels: 5 cases (15.2%) whose SGPT leves never rose above 50 KU were classified as Stage 1; 3 cases with chronic active hepatitis (9.6%) whose highest SGPT levels were over 200 KU (2 new cases and 1 case with a relapse of chronic inactive hepatitis) as Stage 2 and 1 case (3.0%) seroconverted to anti-HBe positive following an acute relapse of chronic inactive hepatitis as Stage 3. Anti-HBe positives were divided into another three groups similarly according to their mean HBs Ag titer levels: 6 cases (18.2%) whose mean HBs Ag titer levels ranged from 10 to 13 (log 2) were classified as Stage 4; 13 cases (39.4%) whose mean HBs Ag titer levels ranged from 6 to 9 as Stage 5 and 5 cases (15.2%), including 2 cases turned negative to HBs Ag, whose mean HBs Ag titer levels were below 5 as Stage 6. The average age of each group increased wth its clinical stage, namely, 32.6 in Stage 1, 34.3 in Stage 2, 33.0 in Stage 3, 34.5 in Stage 4 and 37.0 in Stage 5, but the average age in Stage 6 was 29.0. 3. All HBe Ag positives showed fluctuations in HBs Ag titer levels. The fluctuations were particularly noteworthy among cases with chronic active hepatitis in Stage 2 during an acute relapse. The HBs Ag titers rose just before the acute relapses in a case of chronic active hepatitis when SGPT levels went over 200 KU. This suggested a proliferation of the virus. On the other hand, in anti-HBe positives, a decrement of the virus was suggested by the fact that an increasing proportion of cases showed their HBs Ag titer levels to fluctuate or to become lower with the progress of stages (p less than 0.05) and two cases turned negative to HBs Ag as plotted in Stage 6. And the proportion of cases with abnormal SGPT levels decreased with the progress of stages (p less than 0.05). One case whose SGPT level was 125 KU, highest among anti-HBe positives, followed the clinical course of chronic inactive hepatitis and lowered in HBs Ag titer. 4. Between HBe Ag and anti-HBe cases, there were considerable differences in the occurrence of liver disturbances and their clinical courses...

Adult↗
PubMed1981

Gel chromatographic separation of human C-peptide and proinsulin.

The immunoreactivity of circulating C-peptide is separated into two main peaks on a Bio-Gel column; the faster peak should not be proinsulin but an associated C-peptide without a covalent bond. Proinsulin is in fact eluted in the fraction prior to the faster eluting peak of C-peptide immunoreactivity with 1 M acetic acid as the eluting buffer. Therefore the use of gel chromatography to study C-peptide and proinsulin needs to be carefully re-evaluated, although the method has been established as one of the standard methods.

C-Peptide↗
PubMed1981

Comparison of coronary arteriographic findings during angina pectoris associated with S-T elevation or depression.

Coronary arteriographic findings during an attack of angina pectoris associated with S-T segment elevation and angina associated with S-T depression were compared in 54 patients. Thirty-eight attacks with S-T segment elevation included 2 that were spontaneous, 6 induced by methacholine, 4 by epinephrine with or without propranolol, 9 by arm exercise, 5 by hyperventilation with or without Tris-buffer infusion and 12 by ergonovine maleate. Twenty-nine of the 38 attacks were associated with total occlusion, 8 with subtotal occlusion and 1 with diffuse narrowing of a major coronary artery caused by spasm. Twenty-six attacks with S-T segment depression included 3 induced by methacholine, 13 by arm exercise, 3 by hyperventilation with or without Tris-buffer infusion and 7 by ergonovine maleate. Eight of the 26 attacks were associated with subtotal occlusion and 9 with diffuse narrowing of a major coronary artery caused by spasm; 3 attacks were associated with total occlusion of a major coronary artery well supplied with collateral vessels and 2 with total occlusion of a small coronary branch caused by spasm. Four attacks were associated not with spasm but with fixed subtotal occlusion of a major coronary artery (3 attacks) or total occlusion of a major coronary artery receiving collateral vessels (1 attack). Only 2 of the 31 patients with S-T segment elevation had collateral vessels compared with 8 of the 16 patients with S-T segment depression (p less than 0.001). It is concluded that angina pectoris associated with S-T segment elevation usually indicates more severe myocardial ischemia than angina associated with S-T segment depression.

Adult↗
PubMed1981

Isolation of Clostridium difficile from the feces and the antibody in sera of young and elderly adults.

Attempts were made to isolate Clostridium difficile from a total of 431 fecal specimens from 149 young and 213 elderly healthy adults, and 69 elderly adults with cerebrovascular disease but no gastrointestinal disease. C difficile was isolated from 49 specimens, and the frequency of isolation was 15.4% in healthy young adults, 7.0% in healthy elderly adults, and 15.9% in elderly adults with cerebrovascular disease. Thirty-four (about 70%) of the 49 C. difficile strains isolated produced cytotoxin which was neutralized by Clostridium sordellii antitoxin in vitro; in both young and elderly adults approximately 30% of the C. difficile isolates were nontoxigenic. The mean concentration of C. difficile in feces was 10(4.1)/g in young adults and 10(4.6)/g in elderly adults, with a range of 10(2.0) to 10(6.9)/g. Antibody against C. difficile toxin was found in most of the sera obtained from young adults carrying toxigenic C. difficile, but not in sera of elderly adults, no matter how abundant was toxigenic C. difficile in the feces.

Adult↗
PubMed1981

Agglutination, toxigenicity and sorbitol fermentation of Clostridium difficile.

A total of 79 Clostridium difficile strains from different sources (50 strains from the fecal specimens of healthy adults, 13 from patients receiving antibiotics without gastrointestinal complications, 13 from antibiotic-associated pseudomembranous colitis (PMC) or diarrhea patients, and three strains from ATCC) were investigated for agglutinability, using formol-treated cells as antigen, in relation to toxigenicity. C. difficile strains tested were divided into four serovars, I, II, III, and IV, by the cross-agglutination test. The agglutinin absorption test revealed that strains of serovar I, agglutinable with high titers (5,120-10,240) to antiserum prepared against a highly toxigenic C. difficile strain, ATCC 17859, possessed the serovar-specific antigen. All of the strains of serovar I were highly toxigenic and all 13 strains isolated from the fecal specimens of antibiotic-associated PMC or diarrhea patients belonged to this serovar, whereas 19 (38%) out of 50 strains from healthy adults and four (30.8%) out of 13 strains from patients receiving antibiotics without gastrointestinal complications possessed this antigen. None of the strains of other clostridial species than C. difficile were agglutinated by the three reference antisera used. Further study on the sugar fermentation test disclosed that sorbitol-fermenting property of C. difficile if very closely related to the toxigenicity and agglutinability.

Agglutination Tests↗