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M Tsukamura

Publications and source records attributed to M Tsukamura.

At least 55 records · Page 3Linked to original sources
PubMed1989

[A supplement study on the in vitro activity of sulfadimethoxine on Mycobacterium avium complex--combined effect with other antituberculosis drugs].

Previously the author observed that sulfadimethoxine is most effective among sulfa drugs against Mycobacterium avium complex strains (Tsukamura, M.: Kekkaku 58: 247-250, 1983) and used this drug in the treatment of pulmonary infection caused by M. avium complex (Tsukamura, M.: Kekkaku 59: 33-37, 1983). In the present study, some supplemental observations were carried out on the in vitro activity of this drug. In vitro susceptibility testing of sulfadimethoxine by the use of Ogawa egg medium was influenced by the number of viable bacteria (colony-forming units) used in the susceptibility testing. By the use of small inocula (50 to 100 colony-forming units), minimal inhibitory concentration (MIC) was determined as 0.8 to 3.13 micrograms/ml, whereas, by the use of large inocula, the MIC was determined as 6.25 to 25 micrograms/ml. Furthermore, the prolongation of incubation time resulted in the elevation of the MIC. The finding shows that the activity of this drug is only to delay the growth. Comparing various combinations with low concentrations of other drugs, combinations with p-aminosalicylate, isoniazid and pyrazinamide seemed to be antagonistic, and combinations with the other drugs seemed to be additive. The influence of the inoculation size on the reading of MICs were compared in Mycobacterium tuberculosis and M. avium complex strains. The susceptibility testings to most drugs were influenced by the inoculation size. However, the testings to ethionamide, ethambutol and isoniazid in M. tuberculosis strains were less influenced by the inoculation size. In contrast, the susceptibility testings to ethionamide and isoniazid in M. avium complex strains seemed to be more influenced.(ABSTRACT TRUNCATED AT 250 WORDS)

Antitubercular Agents↗
PubMed1989

[In vitro susceptibility testing of nontuberculous mycobacteria to streptomycin, kanamycin and enviomycin].

In vitro susceptibility testing to streptomycin, kanamycin and enviomycin was carried out in nontuberculous mycobacteria and the results were compared with those of M. tuberculosis strains. Among nontuberculous mycobacteria tested, only M. xenopi strains exhibited similar minimal inhibitory concentration (MIC) values to streptomycin with M. tuberculosis strains. On the other hand, M. xenopi, M. malmoense and M. marinum strains showed the same MIC values to kanamycin with the MIC values for M. tuberculosis strains. The MICs of enviomycin for M. kansasii, M. malmoense, M. szulgai, M. xenopi and M. marinum strains were similar to those for M. tuberculosis strains. Out of 64 strains of M. avium complex, the MIC value similar to that for M. tuberculosis strains was shown in 16% of strains to streptomycin, in 42% of strains to kanamycin, and in 50% of strains to enviomycin.

Enviomycin↗
PubMed1989

[Evaluation of clinical efficacy of rifampicin in the treatment of nontuberculous mycobacteriosis from in vitro susceptibility testing].

In vitro susceptibility testing of various mycobacteria (a total of 295 strains) to rifampicin was carried out using Ogawa egg medium and inoculation of 0.02 ml-samples from 10 mg wet weight per ml suspensions, which were prepared from 10 day-old cultures (M. tuberculosis, 21 day-old cultures; M. fortuitum, 3 day-old cultures). The minimal inhibitory concentration (MIC) was determined after incubation at 37 degrees C for 14 days (M. tuberculosis and M. xenopi 21 days and M. fortuitum 5 days). MIC of M. tuberculosis strains, which were isolated from patients who were untreated previously by any antituberculosis drugs, was in the range of 3.13 to 12.5 micrograms/ml, thus the critical concentration of rifampicin, in which the clinical efficacy of rifampicin could be expected, was determined as 12.5 micrograms/ml. The percentage of strains of each species which are susceptible to this critical concentration is shown in Table 1. In M. avium complex strains, 50% of the strains were inhibited by rifampicin equal to or lower than the critical concentration. However, it is considered to be difficult to cure the disease completely even in these cases, because of the lack of other effective combination drugs with rifampicin. Monotherapy with rifampicin or that with less effective combined drugs would result in development of rifampicin-resistant population and failure of treatment. In successive studies, we will try to find out best possible combination drugs. From this study, the highest efficacy of rifampicin treatment was expected in the disease due to M. kanasaii and the lowest efficacy in the disease caused by M. fortuitum.

Humans↗
PubMed1989

[A taxonomic study on a mycobacterium which caused a skin ulcer in a Japanese girl and resembled Mycobacterium ulcerans].

A taxonomic study has been made on a mycobacterial strain isolated from skin ulcer lesion of a 19 year-old Japanese girl who has lived only in Japan. By numerical classification, in which 108 characters were used, 6 isolates of this strain formed one cluster together with Mycobacterium ulcerans strains. However, the isolates were distinguished from the M. ulcerans strains, forming a subcluster. The isolates were differentiated by the characters shown in Table 2 from authentic M. ulcerans strains. The mycolic acids of the strain ATCC 33788 isolated from Japanese girl were distinguished from those of the type strain ATCC 19423 of M. ulcerans. The number of carbon atoms of alpha-mycolate of the former centered at 80, whereas those of the strain ATCC 19423 at 76. The number of carbon atoms of the alpha-unit was 24 in both strains and the number of double bonds was 2 in both strains. The strain ATCC 33788 showed a 100% similarity with the strain ATCC 19423 in DNA hybridization. In view of the above results, we have concluded that the strain belongs to a new subspecies of M. ulcerans (M. ulcerans subsp. shinshuense). Until now, M. ulcerans infection has occurred only in three area of the world, Africa, Oceania, and South and Middle America. Our case is the first case of M. ulcerans infection discovered in an area other than the above. However, the strain was not the same as the M. ulcerans described previously but differed from it in mycolic acids and some biological and biochemical characteristics.

Adult↗
PubMed1989

[Interrelationship among colonial morphology, susceptibility to antituberculosis drugs, growth rate, and viability in Dubos liquid medium in Mycobacterium avium complex strains].

Interrelationship among colonial morphology, susceptibility to antituberculosis drugs, growth rate, and viability in Dubos liquid medium were studied in Mycobacterium avium complex strains, which were not exposed to any antituberculosis drugs. All five strains that were relatively susceptible to the majority of antituberculosis drugs formed smooth, opaque, domed colonies (SmD) on 7H10 agar medium, and all five strains that were naturally resistant to those drugs formed smooth, transparent, flat colonies (SmT). The SmD colony-forming strains showed small, domed, smooth colonies (DS-type) on Ogawa egg medium, and the SmT colony-forming strains usually large, flat, wrinkled colonies (FW-type) on Ogawa egg medium. However, there was one exceptional strain (11004) that formed DS-type colonies on Ogawa egg medium and SmT-type on 7H10 agar medium. Accordingly, the SmD morphology correlated with drug susceptibility and the SmT colonial morphology with drug resistance. All six DS-colony-forming strains had slow growth rates on Ogawa egg medium, whereas all four FW-colony-forming strains had rapid growth rates on Ogawa egg medium. However, such correlation was not observed in Dubos liquid medium. When the viability was defined as a ratio of the number of colony-forming units contained in 1 mg wet weight of bacteria, the five drug-susceptible strains usually showed low viability and the five drug-resistant strains showed high viability in the Dubos liquid medium. The above four characteristics, colonial morphology, drug susceptibility, growth rate on Ogawa egg medium, and viability in Dubos liquid medium, usually correlated with each other.(ABSTRACT TRUNCATED AT 250 WORDS)

Antitubercular Agents↗
PubMed1989

[Cross-resistance relationships of antituberculosis drugs in Mycobacterium avium complex].

At present, infection caused by Mycobacterium avium complex is usually treated by chemotherapy of antituberculosis drugs. However, cross-resistance relationships of antituberculosis drugs in the M. avium complex have not yet been studied. In the present study, we studied on this subject using three strains which were isolated from sputum specimens of patients who were not treated by any antituberculosis drugs: strain 13008 (serotype 20), strain 13016 (serotype 4) and strain 13034 (serotype 18). The methods used for isolating mutants resistant to rifampicin, isoniazid, ethambutol, streptomycin, kanamycin and/or enviomycin were described previously (Tsukamura, M: Kekkaku 62: 445-458, 1987). Mutants resistant to ethionamide were isolated from strains 13008 and 13016 at a rate of 10(-6) and mutants resistant to kitasamycin at a rate of 10(-5) to 10(-6) (these were not isolated from strain 13034). In contrast, mutants resistant to minocycline were isolated from strain 13034 only at a rate of 10(-4). Susceptibility testings to antituberculosis drugs were carried out as follows. Bacterial suspensions, 10 mg wet weight/ml, were prepared from ten day-old cultures of the strains growing on Ogawa egg medium slants. Each 0.02 ml-sample of the suspensions was inoculated onto Ogawa egg medium with or without a drug by a spiral loop. The media inoculated were incubated at 37 degrees C for 14 days. Minimal inhibitory concentration was determined as a concentration, on which no membraneous growth could occur. The results are shown in Tables 1 to 3. Cross-resistance relationships were observed only between ethionamide and isoniazid. Ethionamide-resistant mutant strains were resistant to isoniazid.(ABSTRACT TRUNCATED AT 250 WORDS)

Antitubercular Agents↗
PubMed1989

[Differentiation between Mycobacterium malmoense and Mycobacterium nonchromogenicum by ethambutol susceptibility].

Mycobacterium malmoense strains are resistant to 1 microgram/ml ethambutol in Ogawa egg medium, whereas Mycobacterium nonchromogenicum strains are susceptible to this concentration. Therefore, these two Group III nonphotochromogens are differentiated clearly from each other by the susceptibility test for ethambutol 1 microgram/ml. Ninety-five % of Mycobacterium avium complex strains are resistant to this concentration, while M. nonchromogenicum strains are susceptible. Therefore, the test serves for differentiating M. nonchromogenicum from M. avium complex. Previously, Tsukamura (Kekkaku 45: 237, 1970) reported that pathogenic and nonpathogenic mycobacteria of Group II and Group III are differentiated by the susceptibility test to ethambutol, 5 micrograms/ml. However, the use of Ogawa egg medium containing 1 microgram/ml ethambutol is superior to that of 5 micrograms/ml ethambutol for differentiating pathogenic and nonpathogenic ones of the Group III.

Ethambutol↗
PubMed1989

[Sulfadimethoxine as a promising drug in the treatment of infections caused by Mycobacterium kansasii and Mycobacterium xenopi--differentiation between M. kansasii and M. marinum and between M. gordonae and M. scrofulaceum by the susceptibility testing to sulfadimethoxine].

Susceptibility testing to sulfadimethoxine of various mycobacteria was made using Ogawa egg medium containing various concentrations of the drug. Each medium was inoculated by a 0.02 ml-sample of bacterial suspensions (10 mg wet weight per ml) prepared from 10 day-old (M. tuberculosis, 14 day-old) cultures growing on Ogawa egg medium after homogenizing the bacteria by shaking with glass beads. The media inoculated were incubated at 37 degrees C for 14 days (M. marinum, at 28 degrees C). The minimal inhibitory concentration (MIC) was determined as the lowest drug concentration on which the growth of bacteria was completely inhibited. However, residual growth occurred often. This was regarded as negative growth, because control medium containing no drug always exhibited abundant membraneous growth. Of the mycobacteria tested, M. kansasii (MICs, 0.8-3.2 micrograms/ml) and M. xenopi (MICs, 0.2-3.2 micrograms/ml) were most susceptible to this drug. Other mycobacteria showed the MICs higher than 3.2 micrograms/ml. The drug seemed to be useful in the treatment of infections caused by M. kansasii and M. xenopi. Furthermore, the susceptibility testing to sulfadimethoxine was considered to be useful for differentiation between two photochromogens, M. kansasii and M. marinum and for differentiation between two scotochromogens, M. scrofulaceum and M. gordonae (Fig. 3 and 4).

Humans↗
PubMed1989

[Mycelium formation of Mycobacterium avium complex].

The morphology of mycobacteria is usually examined by taking a sample from colonies already developed on the medium surface. By this method, Mycobacterium avium complex is considered to form short rods or a little longer rods and occasionally some filaments. We inoculated test strains on Ogawa egg medium slants by a loop and incubated at 37 degrees C. After incubation for 2, 3 and 4 days, unvisible or only scarcely visible growth was taken by loop and placed on slides. The samples were stained by the Ziehl-Neelsen method and observed microscopically. Of 50 strains of M. avium complex examined, 4 strains showed mycelia after incubation for 3 days. These mycelia were not observed after incubation for 7 days when visible colonies developed but rods were observed. Other 46 strains did not show mycelium but showed filamentous growth after 3 days. The change observed was very similar to morphological change of nocardiae which first formed mycelia and thereafter the mycelia were divided into rods. In other slowly growing mycobacteria, M. tuberculosis, M. bovis, M. kansasii, M. scrofulaceum, M. gordonae, M. marinum and M. nonchromogenicum, such mycelium formation was not observed. The mycelium or filament formation in early stage of the growth seemed to be specific for M. avium complex together with M. xenopi.

Mycobacterium avium Complex↗
PubMed1989

[Evaluation of clinical efficacy of isoniazid and ethambutol in the treatment of nontuberculous mycobacteriosis based on in vitro susceptibility testing].

Comparing minimal inhibitory concentrations (MICs) determined in various nontuberculous mycobacteria with those for Mycobacterium tuberculosis strains, which were isolated from patients who were untreated previously by any antituberculosis drugs, clinical efficacy of isoniazid and ethambutol in the treatment of nontuberculous mycobacteriosis was evaluated. The MICs of isoniazid for M. tuberculosis strains were 0.03-0.1 microgram/ml, whereas the MICs for M. xenopi strains were 0.1-0.4 microgram/ml, those for M. szulgai 0.2-0.8, and those for M. kansasii 0.8-1.6 micrograms/ml. The fact that M. xenopi strains are susceptible to isoniazid was reported previously, and in this study, it was shown that M. szulgai and M. kansasii are also considerably susceptible to isoniazid. Isoniazid may be useful in the treatment of infection due to these mycobacteria. The MICs of ethambutol for M. tuberculosis strains ranged from 0.8 to 3.13 micrograms/ml. The percentages of strains of various mycobacteria, which are susceptible to 3.13 micrograms/ml ethambutol, were 100% in M. szulgai, 100% in M. nonchromogenicum, 90% in M. gordonae, 88% in M. marinum, 77% in M. kansasii, 46% in M. malmoense, and 30% in M. scrofulaceum. In contrast, the percentage in M. avium complex strains remained only 19%. It has been suggested that ethambutol is effective in the treatment of diseases caused by M. szulgai, M. marinum and M. kansasii.

Drug Resistance, Microbial↗
PubMed1988

Changes of the biotype of Mycobacterium avium-Mycobacterium intracellulare complex causing lung disease in Japan.

A survey was carried out on the biological and biochemical characteristics of 661 strains of Mycobacterium avium-M. intracellulare complex that caused lung disease in the period 1976 to 1986. The results showed that the proportion of strains which showed 2-week-arylsulphatase activity and that of those which were able to utilize glucose as sole carbon source in the presence of glutamate-nitrogen decreased markedly, and that the proportion of those which utilized neither n-butanol nor iso-butanol as sole carbon sources in the presence of ammoniacal nitrogen increased markedly over these 11 years. These findings indicate that the predominant biotype changed from M. intracellulare to M. avium during the period under study. This postulate is supported by a limited study of the serovars present among the isolates.

Arylsulfatases↗
PubMed1988

Human disease due to Mycobacterium smegmatis.

Mycobacterium smegmatis is a rapidly growing environmental species not considered a human pathogen. We identified 22 human isolates of M. smegmatis from Australia and the southern United States: 19 were from skin or soft-tissue infections, and none were from urine or the male genital tract. These isolates closely resembled Mycobacterium fortuitum, except for a negative three-day arylsulfatase test; growth at 43-45 C; a low semiquantitative catalase test; and, in 50% of isolates, a late-developing, yellow-to-orange pigment. The isolates were biochemically identical to four reference strains and the type strain of M. smegmatis. Isolates were resistant to isoniazid and rifampin but susceptible to ethambutol, doxycycline, sulfamethoxazole, ciprofloxacin, imipenem, and amikacin. Eleven patients treated on the basis of in vitro susceptibility tests responded well to therapy. The similarity of M. smegmatis to M. fortuitum and the failure to recognize that the former is an environmental species may have contributed to previous failures to recognize it as a human pathogen.

Arylsulfatases↗
PubMed1988

Structure and molecular species composition of three homologous series of alpha-mycolic acids from Mycobacterium spp.

Three homologous series of alpha-mycolic acids (dicyclopropanoyl acids, monocyclopropanoyl monoenoic acids and dienoic acids) from 16 rapidly growing and 14 slowly growing mycobacteria were separated by argentation thin-layer chromatography and analysed by gas chromatography/mass spectrometry of their trimethylsilyl ether derivatives. Mycobacterial species were separated into five groups. Strains of group A contained similar amounts of even and odd carbon-numbered dienoic acids, with a methyl branch on the odd acids and a C24-alpha-unit, as typified by Mycobacterium fortuitum and M. chitae. Group B strains possessed similar amounts of even carbon-numbered dicyclopropanoyl alpha-mycolic acids and odd carbon-numbered unsaturated acids with C22- and C24-alpha-units, as found in M. phlei and M. diernhoferi. Group C strains contained mainly even carbon-numbered dicyclopropanoyl acids with C22- and C24-alpha-units, as shown by M. vaccae and M. aurum. Group D strains possessed mainly odd carbon-numbered dienoic acids with a methyl branch and a C24-alpha-unit, as seen in M. triviale and M. nonchromogenicum. Group E strains had mainly even carbon-numbered dicyclopropanoyl acids with C24- or C26-alpha-units, as found in M. avium and M. tuberculosis. Many rapidly growing mycobacteria also produced alpha'-mycolic acids which were shorter in the length of the main carbon chain but whose alpha-units were the same as those in alpha-mycolic acids from the same species. These alpha'-mycolic acids had either one or two double bonds and showed variations in both their unsaturation and overall size, which may be useful in taxonomic studies.

Carboxylic Acids↗
PubMed1988

Differentiation between genera Rhodococcus and Nocardia by susceptibility testing to kanamycin and some other antituberculosis agents.

The test for susceptibility to kanamycin is useful for differentiating between the genera Rhodococcus and Nocardia. All rhodococci except R. equi, R. erythropolis, and R. aurantiacus are susceptible to kanamycin, whereas all nocardiae except N. otitidis-caviarum are resistant to kanamycin. Tests for susceptibility to rifampicin, streptomycin, and minocycline also are useful for differentiating among the species of each genus.

Animals↗
PubMed1988

Relationship between mycobacterial species and their carotenoid pigments.

A study of the relationship between mycobacterial species and their carotenoid pigments was carried out. According to the carotenoid pigments contained, the mycobacterial species tested were divided into four groups: the first group of Mycobacterium kansasii and M. marinum, which formed principally only beta-carotene; the second group of M. gordonae, M. scrofulaceum, M. szulgai, M. xenopi, M. flavescens, M. phlei, M. rhodesiae, M. neoaurum, and M. aichiense, which formed beta-carotene and a zeaxanthin-like substance; the third group of M. aurum and M. obuense, which formed beta-carotene and an eschscholtzxanthin-like substance; and the fourth group of M. chubuense and M. tokaiense, which formed beta-carotene and zeaxanthin- and eschscholtzxanthin-like substances. The common carotenoid pigment throughout the genus Mycobacterium was beta-carotene and the hypophasic carotenoids differed according to the species.

Carotenoids↗
PubMed1988

A case of lung infection caused by an unusual strain of Nocardia farcinica.

A case of lung infection caused by an unusual strain of Nocardia farcinica is reported. This is the third case of the N. farcinica infection in this country. The strain failed to utilize rhamnose as sole carbon source, but could be identified by a numerical identification method. The mycolic acids contained 1-3 double bonds and the numbers of the carbon atoms of the mycolic acids were 50 to 60, average 56.

Aged↗
PubMed1988

The isolation of Mycobacterium avium complex from soil, water, and dusts.

Previously, it was difficult to isolate the Mycobacterium avium complex from soil, water, and dusts, because rapidly growing mycobacteria always overgrew slowly growing ones. We used Ogawa egg medium containing both ethambutol and ofloxacin, which inhibit the nonpathogenic slowly growing mycobacteria and most rapidly growing mycobacteria, respectively, as an aid to screen for pathogenic slowly growing mycobacteria; we could thereby isolate a number of the M. avium complex and M. scrofulaceum strains from soil, water, and dusts in this country.

Bacteriological Techniques↗