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At least 19 recordsLinked to original sources
PubMed1992

Bacteriostatic and bactericidal activity of antituberculosis drugs against Mycobacterium tuberculosis, Mycobacterium avium-Mycobacterium intracellulare complex and Mycobacterium kansasii in different growth phases.

Bacteriostatic and bactericidal activities of rifampicin, isoniazid, streptomycin, enviomycin and ethambutol against Mycobacterium tuberculosis, Mycobacterium avium--M. intracellulare complex and Mycobacterium kansasii were studied in different growth phases. Bacteriostatic activities of the drugs were similar in different growth phases, except isoniazid. M. tuberculosis was much less susceptible to isoniazid in the lag phase than in the log and the stationary phases. In contrast, bactericidal activity was influenced by the growth phase. M. tuberculosis was killed by isoniazid, streptomycin and rifampicin. The bactericidal activity of isoniazid was strongest. The bactericidal activity of isoniazid and streptomycin was most marked in the log phase. M. avium complex and M. kansasii resisted the bactericidal activity, but some strains of M. avium complex were killed by streptomycin and enviomycin, and the activities of these two drugs were most marked in the lag phase.

Antitubercular Agents↗
PubMed1990

T-cellular immune reactions (in macrophage inhibition factor assay) against Mycobacterium paratuberculosis, Mycobacterium kansasii, Mycobacterium tuberculosis, Mycobacterium avium in patients with chronic inflammatory bowel disease.

A mycobacterial aetiology has been suggested for Crohn's disease. A slow growing mycobacterium, biochemically and genetically identical to M paratuberculosis, the causative agent of enteritis in ruminants (Johne's disease), has been isolated from gut specimens of patients affected by Crohn's disease. If M paratuberculosis or other mycobacteria play a role in the pathogenesis of Crohn's disease, then patients may have been sensitised to these mycobacteria or show an anergy immune reaction. We therefore investigated the T-cell mediated immune response to sonicates of M paratuberculosis, M kansasii, M avium, and M tuberculosis in 35 patients with Crohn's disease, 28 with ulcerative colitis, and 25 controls using a macrophage inhibition factor assay on peripheral blood lymphocytes. Two types of reaction patterns were identified--that is, 'responders' (subjects with a macrophage inhibition factor assay in which a dose response relation was present and a percentage of inhibition exceeding 20%), and 'non-responders'. There was no significant difference in the prevalence of responders (59%-80%) and non-responders (20%-41%) to these mycobacteria between the group of Crohn's disease, ulcerative colitis, and control group. We found also that a large proportion of controls showed T-cell immunisation to the mycobacteria which supports the contention that the antigens are practically commensal. Our results do not support the proposed involvement of mycobacteria in the pathogenesis of Crohn's disease.

Adult↗
PubMed1990

[Cross-resistance relationship between streptomycin and kanamycin resistances in Mycobacterium smegmatis (strain Jucho)--comparison of the development patterns of resistances to streptomycin and kanamycin among Mycobacterium tuberculosis, Mycobacterium avium complex, and Mycobacterium smegmatis].

The resistance development pattern of Mycobacterium smegmatis strain 17023 (Jucho) to streptomycin and kanamycin was studied. The medium used was Ogawa egg medium, and the level of resistance was determined for each clone derived from single colony by the 'actual count' method. Hence, the resistance level was estimated as the highest concentration of drugs, in which small inocula consisting of 20 to 100 colony-forming units could grow after seven days incubation. Only one type of resistance mutants resistant to more than 1,000 micrograms/ml streptomycin was isolated and these mutants were also resistant to 8 micrograms/ml kanamycin. On the other hand, only one type of kanamycin-resistant mutants resistant to 8 micrograms/ml kanamycin was isolated and these mutants were also resistant to more than 1,000 micrograms/ml streptomycin. Accordingly, there was a complete cross-resistance relationship between streptomycin and kanamycin resistances. Therefore, there existed only one phenotype, which is simultaneously resistant to streptomycin and kanamycin. The mutants occurred at a rate of about 2 x 10(-8) per viable bacterial population of the parent strain. Streptomycin-dependent mutants occurred at a rate of about 2 x 10(-9). The number of resistant phenotypes to streptomycin and kanamycin was only one in M. smegmatis, while it was five in M. tuberculosis and 2 or 3 in M. avium complex (Tsukamura, M. and Mizuno, S.: J. Gen. Microbiol. 88: 269-274, 1975; Tsukamura, M.: Kekkaku 62: 445-458, 1987). The simplicity of the resistance system of M. smegmatis suggests that this organism is evolutionally primitive in the world of mycobacteria.

Drug Resistance, Microbial↗
PubMed1992

Mycobacterium xenopi, Mycobacterium fortuitum, Mycobacterium kansasii, and other nontuberculous mycobacteria in an area of endemicity for AIDS.

Between 1981 and 1990, cultures of specimens from 86 patients at State University of New York-Health Sciences Center at Brooklyn were positive for nontuberculous mycobacteria other than Mycobacterium avium/Mycobacterium intracellulare complex or Mycobacterium gordonae. The most common species isolated were Mycobacterium xenopi (33), Mycobacterium fortuitum (28), Mycobacterium kansasii (7), and Mycobacterium chelonae (6). Thirty-five patients (41%) had clinical and/or serological evidence of human immunodeficiency virus (HIV) infection. Patients from whom M. xenopi and M. kansasii were isolated were significantly more likely to be infected with HIV than were the remaining patients in this series. Most of the mycobacterial isolates were cultured from respiratory secretions. However, extrapulmonary infections with M. fortuitum, M. xenopi, M. kansasii, Mycobacterium terrae, and Mycobacterium scrofulaceum did occur among the HIV-infected patients.

Adolescent↗
PubMed1992

Proposal of Mycobacterium peregrinum sp. nov., nom. rev., and elevation of Mycobacterium chelonae subsp. abscessus (Kubica et al.) to species status: Mycobacterium abscessus comb. nov.

We studied the taxonomic positions of the rapidly growing organism Mycobacterium fortuitum and phenotypically related organisms. We confirmed that "Mycobacterium peregrinum" ATCC 14467T (T = type strain) is genetically independent of M. fortuitum ATCC 6841T by using various DNA hybridization conditions. Strains that were genetically identified as "M. peregrinum" were phenotypically differentiated from M. fortuitum ATCC 6841T. Thus, we propose that "M. peregrinum" should be revived as an independent species, Mycobacterium peregrinum sp. nov., nom. rev. The type strain is strain ATCC 14467. M. fortuitum subsp. acetamidolyticum ATCC 35931T exhibited a high level of DNA relatedness to M. fortuitum ATCC 6841T. The hybridized DNAs maintained stable heteroduplexity at high stringency; thus, we confirmed that M. fortuitum subsp. acetamidolyticum is identical to M. fortuitum ATCC 6841T. We found that M. chelonae subsp. abscessus ATCC 19977T is genetically different from M. chelonae subsp. chelonae NCTC 946T on the basis of the results of quantitative hybridization even under optimal conditions. There was no reason to maintain this organism as a subspecies of M. chelonae. Thus, we propose that M. chelonae subsp. abscessus should be elevated to species status as Mycobacterium abscessus (Kubica et al.) comb. nov. The type strain is strain ATCC 19977.

Colorimetry↗
PubMed1990

Analysis of cellular fatty acids and proteins by capillary gas chromatography and sodium dodecyl sulphate polyacrylamide gel electrophoresis to differentiate Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum (MAIS) complex species.

Infections due to atypical mycobacteria have increased during the past 30 years. Species of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum are among the most common non-tuberculous mycobacteria isolated from patients with AIDS or immunosuppressed. These three organisms are taxonomically closely related and identification, according to cultural characteristics and biochemical tests, is not always evident, so some of these related strains are grouped in a "MAIS" complex. Analysis of cellular constituents is an aid to identification. Gas chromatography was used to study mycolic acids and a secondary alcohol was found which is a discriminating constituent between M. scrofulaceum and the other two species. The lipidic analysis was not able to separate M. avium and M. intracellulare, so cell proteins were considered. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of proteins reflects genetic relatedness between strains; the different patterns obtained from these three species are described and it is shown that this method is very useful in classification and epidemiology.

Bacterial Proteins↗
PubMed1990

Identification of various serovar strains of Mycobacterium avium complex by using DNA probes specific for Mycobacterium avium and Mycobacterium intracellulare.

Reference strains of the Mycobacterium avium complex (MAC) belonging to serovars 1 to 28 were examined with DNA probes (Gen Probe Rapid Diagnostic System for the MAC; Gen Probe Inc., San Diego, Calif.) specific for either M. avium or Mycobacterium intracellulare. This study revealed that the earlier designations of the MAC serovars, in which serovars 1 to 3 and 4 to 28 were regarded as M. avium and M. intracellular, respectively, should be revised as follows. First M. avium includes serovars, 1 to 6, 8 to 11, and 21. Second, M. intracellulare includes serovars 7, 12 to 20, and 25. However, other serovars, such as serovars 22 to 24 and 26 to 28, involve M. intracellulare, Mycobacterium scrofulaceum, and MAC that are lacking in the reactivity with either DNA probe and that are too disordered to enable a conclusive description here, particularly concerning their taxonomic positions in the MAC.

Antigens, Bacterial↗
PubMed1992

Epidemiology of infection by nontuberculous mycobacteria. Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum in acid, brown-water swamps of the southeastern United States and their association with environmental variables.

Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum (MAIS) organisms were isolated and identified from waters, soils, aerosols, and droplets ejected from water collected from four geographically separate aquatic environments (Okefenokee Swamp, GA; Dismal Swamp, VA; Claytor Lake, VA; and Cranberry Glades, WV) during several seasons. Recovery of MAIS was significantly higher from waters, soils, and aerosols collected from the two acid, brown-water swamps located in the southeastern coastal plain. High MAIS numbers correlated with warmer temperature, low pH, low dissolved oxygen, high soluble zinc, high humic acid, and high fulvic acid. This research, in relation to previous findings for the geographic distribution and physiologic ecology of MAIS, supports the conclusion that waters, soils, and aerosols of the acid, brown-water swamps of the southeastern United States coastal plain represent major environmental sources likely connected with the higher incidence of human infection in this region.

Georgia↗
PubMed1991

[Identification of Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium tuberculosis complex by Gen-Probe Rapid Diagnostic System].

DNA probe testing for Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium tuberculosis complex (MTC) was performed using Gen-Probe Rapid Diagnostic System (Gen-Probe Inc., San Diego, Calif., U.S.A.). By DNA probe test carried out blindfold for 48 mycobacterial strains with code numbers obtained from Kyoto University (Prof. F. Kuze), 13, 7, and 5 strains were identified as to be M. avium, M. intracellulare, and MTC, respectively. The diagnostic specificity and sensitivity of this testing were 100%. In this experiment, % hybridization of M. avium complex (MAC) and MTC were 25-55% and 45-52%, respectively. DNA probe test for 54 MTC strains including M. tuberculosis, M. bovis, M. africanum and M. microti revealed that 53 strains, except for one strain donated as a niacin-negative M. tuberculosis, reacted with MTC probe but not with MAC-probes. The one exceptional strain reacted with both the MTC- and M. avium-probes. However, when ten colonies randomly isolated from this strain on 7H11 agar plate were subjected to the DNA probe test again, all of these colonies reacted with M. avium probe, but not with MTC probe. Moreover, one representative colony was found to have alpha-antigen specific for the MAC.

DNA Probes↗
PubMed1992

Separation of Mycobacterium bovis BCG from Mycobacterium tuberculosis and Mycobacterium bovis by using high-performance liquid chromatography of mycolic acids.

Profile analysis of mycolic acid ester patterns of Mycobacterium tuberculosis, Mycobacterium bovis, and Mycobacterium bovis bacillus Calmette-Gúerin (BCG) using high-performance liquid chromatography indicated that separation of BCG from M. tuberculosis and M. bovis by elution and relative retention times is possible. Mycolic acid patterns of BCG eluted from the column 0.5 min before M. tuberculosis or M. bovis, resulting in relative retention times for two peaks not seen in the pattern of M. tuberculosis or M. bovis. Identification was confirmed by phage typing, which has been the standard procedure for confirmation of BCG strains. These results showed that high-performance liquid chromatographic analysis of mycolic acid esters can be used in the mycobacterial reference laboratory for separation of BCG from M. tuberculosis and M. bovis.

Bacteriophage Typing↗
PubMed1990

High-performance liquid chromatography patterns of mycolic acids as criteria for identification of Mycobacterium chelonae, Mycobacterium fortuitum, and Mycobacterium smegmatis.

Rapidly growing mycobacteria of clinical significance were identified by mycolic acids detected with high-performance liquid chromatography. Mycolic acids from whole cells were extracted, derivatized, and detected by a modified high-performance liquid chromatography procedure in less than 3 h. Use of an internal standard allowed differentiation of Mycobacterium chelonae and Mycobacterium fortuitum by comparison of relative retention times. Peak height ratios were used for subidentification of M. chelonae strains; however, M. fortuitum and Mycobacterium smegmatis could not be separated by this system.

Chromatography, High Pressure Liquid↗
PubMed1979

Phagosome-lysosome fusion and cyclic adenosine 3':5'-monophosphate in macrophages infected with Mycobacterium microti, Mycobacterium bovis BCG or Mycobacterium lepraemurium.

When ingested by mouse peritoneal macrophage monolayers, live Mycobacterium microti caused a sustained increase in monolayer cyclic AMP content and fusion of lysosomes with the bacterium-containing phagosomes was impaired. Ingested live M. bovis BCG caused a transient increase in cyclic AMP and the defect in phagolysosome formation was less pronounced. Dead mycobacteria and live M. lepraemurium neither enhanced monolayer cyclic AMP content nor inhibited phagolysosome formation. Mycobacterium microti and BCG exceeded M. lepraemurium in cyclic AMP-synthesizing activity in vitro but the question of whether bacterial cyclic AMP contributed substantially to the increments in infected macrophages was not resolved. Antibody-coated BCG retained the ability to synthesize cyclic AMP and to enhance monolayer cyclic AMP but lost the ability to inhibit phagolysosome formation in macrophages, The observations are discussed in terms of possible control of phagolysosome formation by cyclic nucleotides.

Cyclic AMP↗
PubMed1991

Gen-Probe Rapid Diagnostic System for the Mycobacterium avium complex does not distinguish between Mycobacterium avium and Mycobacterium paratuberculosis.

Three reference and 16 field strains of Mycobacterium paratuberculosis were tested with the Gen-Probe Mycobacterium avium complex DNA probe (Gen-Probe Inc., San Diego, Calif.). All reference strains and 12 of 16 field strains gave positive hybridization results with the probe. This study shows that the M. avium complex probe does not distinguish between M. avium and M. paratuberculosis and indicates heterogeneity in the 16S rRNA gene of M. paratuberculosis.

Animals↗
PubMed1978

Ocular histopathology in animals experimentally infected with Mycobacterium leprae and M. lepraemurium. 1. Mycobacterium leprae and M. lepraemurium infections in the mouse. 2. Mycobacterium leprae infections in the 9-banded armadillo (Dasypus novemcinctus L.).

At varying periods of time following the successful establishment of systemic infections with Mycobacterium leprae or M. lepraemurium in the mouse and the nine-banded armadillo eyes were examined by light microscopy. Inoculation of bacilli was by the intravenous or intraperitoneal route or directly into the hind footpads; eyes were not directly inoculated in this study. During periods of up to 3 years under laboratory conditions no animal showed evidence of impaired vision or blindness, and the external appearance of both eyes was normal. The ocular histopathology and the sites of accumulation of bacilli are described. In immunologically normal mice infected with M. lepraemurium bacilli were much commoner in extraorbital tissues, but they were, nevertheless, found in various tissues within the orbit, including the ciliary body and sclera. In immunologically normal mice (and one rat) injected with M. leprae of human origin no bacilli were found in the eye, but in mice immunologically depressed by thymectomy and total body irradiation considerable numbers of bacilli were present in the iris and ciliary body and also in the limbal cornea. In the armadillo bacilli were found in large numbers in virtually all tissues except the lens, retina, optic nerve, and aqueous and vitreous humours, but the uveal tract was heavily involved. Findings are discussed in relation to the great frequency of ocular involvement and the importance of immune-complex disease in patients with lepromatous leprosy, and to factors wihch may favour the localisation and multiplication of Mycobacterium leprae in the eye.

Animals↗
PubMed1979

Comparison of proteins from Mycobacterium fortuitum, Mycobacterium nonchromogenicum and Mycobacterium terrae using flat bed electrophoresis.

Polyacrylamide gel electrophoresis of bacterial lysates in a flat bed gives a linear relationship between 1n mol. wt of the proteins and the square root of their migration distances, thereby allowing standardization of different electrophoresis runs and precise comparison between homologous bands. The results obtained with Mycobacterium fortuitum, M. terrae and M. nonchromogenicum strains were used in numerical analysis. Mycobacterium fortuitum and M. nonchromogenicum showed a greater internal similarity than M. terrae, while two strains of the latter clustered with M. nonchromogenicum. The method described allows the comparison of mycobacteria with different generation times and provides a large number of good characters for numerical taxonomy.

Bacterial Proteins↗
PubMed1991

Evaluation of acridinium-ester-labeled DNA probes for identification of Mycobacterium tuberculosis and Mycobacterium avium-Mycobacterium intracellulare complex in culture.

The detectability of mycobacteria in culture by the use of nonisotopic, chemiluminescent DNA probes for Mycobacterium tuberculosis and the M. avium-M. intracellulare complex (MAC) was evaluated and compared with that by the use of 125I-labeled DNA probes for the same mycobacteria. In the assay, rRNA-directed DNA probes labeled with acridinium ester (AE-DNA probes) were used. Unhybridized probes were chemically degraded, and the esterified acridinium on the hybridized probes was hydrolyzed by the addition of alkaline hydrogen peroxide solution, resulting in the production of visible light which was measured with a luminometer. The detection limits of the AE-DNA probes were almost the same as those of the 125I-labeled DNA probes. A total of 107 clinical isolates of mycobacteria (47 isolates of M. tuberculosis, 36 MAC, and 24 atypical mycobacteria other than MAC) were tested. The sensitivity and specificity of the AE-DNA probes for M. tuberculosis were 100% both for the conventional method and with the 125I-labeled DNA probe. The sensitivity and specificity of the AE-DNA probes for MAC were 97.2 and 100%, respectively, for the conventional method and were both 100% with the 125I-labeled DNA probes. Because the procedure is simple, reliable, rapid (it can be completed within an hour), and safe (it does not use radioisotopes), it can easily be performed in any clinical laboratory.

Acridines↗
PubMed1990

Epidemiology of infection by nontuberculous mycobacteria IX. Evidence for two DNA homology groups among small plasmids in Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum.

A 12.9 kb plasmid, pVT2, from a clinical Mycobacterium avium isolate, MD1, was cloned and radiolabeled for use as a DNA probe to examine the relatedness of plasmids in M. avium complex. That probe hybridized with plasmids isolated from M. avium complex strains from the environment (7 of 16) and from non-acquired immunodeficiency syndrome (AIDS) (10 of 17) and AIDS (5 of 6) clinical isolates. The similarity of plasmids from the environment with those from patients supports the hypothesis that the environment is a source of human M. avium complex infection. More striking was the observation that pVT2 hybridized with every plasmid (13 of 13 clinical and 5 of 5 environmental isolates) of 13.5 kb or smaller. A second probe, consisting of a 15.3 kb plasmid (pLR7) from another clinical isolate of the M. avium complex, hybridized with plasmids of 15.3 to 25 kb from environmental and clinical (AIDS and non-AIDS) isolates. There was no hybridization between pVT2 and pLR7. Thus, these two probes define two different groups of small mycobacterial plasmids.

Acquired Immunodeficiency Syndrome↗