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At least 19 recordsLinked to original sources
PubMed1982

[Experimental pathogenicity of isolates of Nocardia asteroides, Nocardia brasiliensis and Nocardia caviae from different sources].

The experimental pathogenicity of 14 isolates of Nocardia brasiliensis, 15 of N. asteroides, and 5 of N. caviae was investigated for the white Swiss mice inoculated intraperitoneally and in the foot pad, and for the guinea-pig and the hamster (Mesocricetus auratus) both inoculated intratesticularly. The guinea-pig was remarkably sensitive to N. asteroides, with an apparent relationship between pathogenicity and thermotolerance, confirming previous observations. Mice were in general less susceptible to this species. In both guinea-pigs and hamsters it was possible to observe typical granules with or without clubs. N. caviae was highly pathogenic for the guinea-pig and the hamster but no mycetomas were produced in the mice inoculated in the foot pad. Isolates of N. brasiliensis from natural sources were scarcely virulent for the different animals. Those of human origin produced significant lesions in the mice inoculated intraperitoneally with granules. Foot pad inoculation of mice with N. brasiliensis caused mycetomas in several animals.

Animals↗
PubMed1963

IMMUNOLOGICALLY ACTIVE POLYSACCHARIDES FROM NOCARDIA ASTEROIDES AND NOCARDIA BRASILIENSIS.

Zamora, A. (University of Mexico, Mexico, D.F.), L. F. Bojalil, and Fernando Bastarrachea. Immunologically active polysaccharides from Nocardia asteroides and Nocardia brasiliensis. J. Bacteriol. 85:549-555. 1963.-Two immunologically active polysaccharides were isolated from Nocardia asteroides (Poly I Na and Poly II Na) and N. brasiliensis (Poly I Nb and Poly II Nb). These polysaccharides were isolated from cell extracts and purified by methanol precipitation, chloroform extraction of extraneous material, and deproteinization with trichloroacetic acid. The crucial step used for separation of Poly I and Poly II from both nocardias was differential solubility. From dried preparations containing both polysaccharides, Poly I was solubilized at pH 10, whereas Poly II remained insoluble and was subsequently solubilized at pH 5. Poly I Na and Poly I Nb are apparently the same. Arabinose and galactose were the monosaccharide constituents of these polysaccharides, and their molar ratios were similar. Furthermore, Poly I Na and Poly I Nb cross-reacted in agar diffusion precipitin tests with rabbit antisera prepared against either N. asteroides or N. brasiliensis. Either polysaccharide absorbed serum antibodies against the other. These polysaccharides can be regarded as groupspecific. Poly II Na and Poly II Nb are different and species-specific. They are composed of arabinose, galactose, and mannose but exhibit different molar ratios of these sugars according to species. They reacted only with homologous antisera.

Allergy and Immunology↗
PubMed1988

Acid phosphatase activity in Nocardia brasiliensis and Nocardia asteroides.

Nocardia asteroides and N. brasiliensis strains were found to possess acid phosphatase activity. This enzyme was found to be cell-associated and its activity paralleled the cell mass increase seen during the Nocardia growth cycle. Of the strains tested, N. brasiliensis exhibited the highest enzymatic activity. Implications of these findings are related to current evidence which indicates that other microbial acid phosphatases may constitute potential pathogenic factors for humans.

Acid Phosphatase↗
PubMed1980

Immunobiology of germfree mice infected with Nocardia asteroides.

Nocardia asteroides GUH-2 was administered either intranasally or by intravenous inoculation into (i) conventionally grown, (ii) germfree, and (iii) lipopolysaccharide-treated germfree NIH:S mice. The number of bacteria within the lungs, brain, kidneys, adrenals, liver, spleen, and blood was quantitated at 3, 24, 72, and 168 h after infection. Further, the histological changes that occurred in each of these organs after infection were studied. The data demonstrated that germfree mice were significantly more susceptible to the acute phase of infection caused by N. asteroides than the conventionally grown animals. The brains and lungs of these mice were affected most dramatically. Pretreatment of the germfree mice with lipopolysaccharide completely reversed this enhanced susceptibility and rendered the animals more resistant to infection than the conventionally grown mice. These observations establish further the role of macrophage activation and the development of cell-mediated immunity in host resistance to nocardia. In addition, the presence of a resident microflora within the host appears to be important in the development of resistance to systemic nocardial infections.

Animals↗
PubMedDate not supplied

[Acute otitis media caused by Nocardia asteroides].

Nocardia asteroides is a bacteria that is distributed widely in nature and produces infection in most organs. Pulmonary nocardiosis is the most common form of clinical presentation. Few references exist regarding ear disease produced by this microorganism. A case of acute otitis media caused by N. asteroides produced subtotal tympanic perforation in a 45-year-old immunocompetent patient. The causal diagnosis was made by pure culture growth, repeated isolation and visualization of the microorganism in Gram-stained specimens of ear exudate. The strain was resistant to cotrimoxazole, but the patient was treated successfully with ciprofloxacin.

Acute Disease↗
PubMed1979

Prosthetic valve endocarditis resulting from Nocardia asteroides.

Nocardia asteroides was isolated from the prosthetic valve of a 64-year-old woman who had died of endocarditis after aortic valve replacement. Multiple blood cultures had all been negative. This organism is increasingly being recognised as a pathogen and is usually sensitive to sulphonamides. These should be tried in culture negative endocarditis unresponsive to standard therapy.

Aortic Valve↗
PubMed2002

Murine polymorphonuclear neutrophils produce interferon-gamma in response to pulmonary infection with Nocardia asteroides.

Nocardia asteroides causes an acute, necrotizing pneumonia characterized by extensive infiltration of polymorphonuclear neutrophils (PMNs) into the lungs. Although PMNs have historically been classified as end-point cells, recent investigations have indicated that PMNs have the ability to secrete cytokines such as interleukin (IL)-4 and IL-12. This study investigated the ability of PMNs to produce cytokines in a murine model of N. asteroides pulmonary infection. Flow cytometric analysis demonstrated the production of interferon-gamma (IFN-gamma), but not IL-4, by PMNs in response to this infection. IFN-gamma production correlated with peak infiltration of PMNs into the lungs. Cell sorting and enzyme-linked immunosorbent assay were used to confirm cytokine production by cells with nuclear morphology characteristic of PMNs. This is the first report of IFN-gamma production by neutrophils in response to an infection in vivo. These results suggest that PMNs play an important role in directing the host toward a T helper cell type 1 phenotypic response in the lungs.

Animals↗
PubMed1992

The timing of exposure of mononuclear phagocytes to recombinant interferon gamma and recombinant tumor necrosis factor alpha alters interactions with Nocardia asteroides.

Nocardia asteroides modulates phagocyte function and grows within macrophages. Because interferon gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) have been shown to activate macrophages to kill a variety of microorganisms, the effects of IFN-gamma and TNF-alpha on the activation of murine macrophages and human monocytes to kill nocardiae were studied. It was found that macrophages or monocytes treated with either IFN-gamma, TNF-alpha, or lipopolysaccharide as a secondary signal did not demonstrate increased microbicidal activity against N. asteroides even though these phagocytes were effective at killing the fungus Coccidioides immitis and the protozoan Toxoplasma gondii. Preincubation of phagocytes for 24 h with these compounds resulted in an enhancement of nocardial growth. In contrast, coincubation of these factors with the nocardiae and mononuclear cells during phagocytosis resulted in inhibition of nocardial growth even though this bacterium was not killed. Therefore, the specific timing of the exposure of the phagocyte in vitro to IFN-gamma or TNF-alpha has a significant effect on its ability to alter nocardial growth.

Colony Count, Microbial↗
PubMed1976

Nocardia asteroides and Nocardia brasiliensis infections in mice.

A model for Nocardia asteroides and Nocardia brasiliensis infections in Swiss white mice has been established without the addition to the inocula of any form of adjuvant. Serial histopathological studies revealed that these two actinomycetes cause lesions that are quite different in their features. An acute suppurative abscess characterizes the lesions of N. asteroides. In the case of N. brasiliensis infections a granuloma is produced in which a striking feature is the presence of large numbers of foam-laden macrophages, although occasional exceptions to this pattern were noted. Electron microscopic studies demonstrated that these macrophages contain within their cytoplasm organisms in varying stages of degeneration. Repeated mortality studies in mice failed to demonstrate differences in mortality rates produced by N. asteroides and N. brasiliensis. Thus, despite relatively trivial biochemical and antigenic differences between these two species of Nocardia, the local pathogenic response is quite different. The presence in the "brasiliensis lesion" of foamy macrophages with intracellular organisms is reminiscent of the histopathological features of lepromatous leprosy and of disseminated Myocobacterium bovis infection when this occurs in the immune suppressed situation. It is possible that N. brasiliensis infection produces a depression of cellular immunity that modifies the local host response to the organism.

Animals↗
PubMed1990

Monoclonal antibodies to Nocardia asteroides and Nocardia brasiliensis antigens.

Nocardia asteroides and Nocardia brasiliensis whole-cell extracts were used as antigens to generate monoclonal antibodies (MAbs). Six stable hybrid cell lines secreting anti-Nocardia spp. MAbs were obtained. These were characterized by enzyme-linked immunosorbent assay, Western blot (immunoblot), and immunofluorescence assay. Although all the MAbs exhibited different degrees of cross-reactivity with N. asteroides and N. brasiliensis antigens as well as with culture-filtrate antigens from Mycobacteria spp., they have the potential for use as reagents in the purification of Nocardia antigens.

Antibodies, Bacterial↗
PubMed1980

An ultrastructural comparison of the cell envelopes of selected strains of Nocardia asteroides and Nocardia brasiliensis.

Growth curves were determined for three strains each of Nocardia asteroides and Nocardia brasiliensis. Two strains of N. brasiliensis and one strain of N. asteroides had longer lag periods of growth than the remaining three strains. All strains had generation times of approximately 5.5 hours. The ultrastructure of the cell envelope of each Nocardia strain in early stationary phase growth was also examined. All the strains had typical trilaminar cell walls and cell membranes. The thickness of the cell wall layers, especially the inner peptidoglycan layer, varied from strain to strain. The inner layer of two strains of N. brasiliensis and one strain of N. asteroides was 12 nm or more in thickness, while that of the remaining three strains was 7 nm thick. These observed differences in growth patterns and/or thickness of the cell wall layers could be correlated to the varying degrees of virulence as well as the divergent pathologies exhibited by these organisms.

Cell Wall↗
PubMed1997

Molecular study of persistence of Nocardia asteroides and Nocardia otitidiscaviarum strains in patients with long-term nocardiosis.

Three Nocardia asteroides and five Nocardia otitidiscaviarum isolates recovered from three patients with long-term nocardiosis were compared by random amplification of polymorphic DNA fingerprinting, antibiotic susceptibility testing, and enzymatic characterization. Results obtained with primer DKU49 (P. Palittapongarnpim, S. Chomyc, A. Fanning, and D. Kunimoto, J. Infect. Dis. 167:975-978, 1993) provide evidence that patient A was infected by two N. asteroides strains during a single episode of nocardiosis and that patients B and C remained infected by the same strain, respectively. Resistance to minocycline that was present in the first isolate recovered from patient B reverted to intermediate resistance in the second isolate and reverted to susceptibility in the third isolate. Resistance to penicillin G and beta-lactams was acquired by the second isolate obtained from patient C.

DNA Fingerprinting↗
PubMed1993

Composition and toxicity of diethyl ether soluble lipids from Nocardia asteroides GUH-2 and Nocardia asteroides 10905.

Virulent Nocardia asteroides GUH-2 and avirulent N. asteroides 10905 contained 8.2% and 10.6% of diethyl ether soluble lipids (DESL) per dry cell mass, respectively. Intraperitoneal (i.p.) inoculation of 250 micrograms of DESL from GUH-2 dissolved in mineral oil was toxic to mice, resulting in weight loss and death of 100% of the animals (20/20) within 20 days. In contrast, DESL from 10905 had very little toxicity, and only one mouse (1/10) died within 30 days. Three fractions resulted from DESL by silicic acid column chromatography: (1) neutral lipids and fatty acids (NFA); (2) glycolipids (GL); and (3) phospholipids (PL). Each fraction dissolved in mineral oil was inoculated into mice as described above. The NFA and PL were not toxic. GL from 10905 had low toxicity (30% of the animals died, 3/10) whereas GL from GUH-2 expressed high toxicity (100% of the animals became cachetic and died, 10/10). GL from 10905 represented a minor component (0.6% of dry cell weight) whereas GL from GUH-2 was more prominent (1.5% of dry cell wt.). Approximately 95% of GL from GUH-2 had properties of an authentic trehalose-6,6'-dimycolate standard. Infrared spectrum of the major glycolipid (GUH-2 GL) had characteristic absorptions in the fingerprint region between 800 cm-1 and 1500 cm-1. Upon alkaline hydrolysis GUH-2 GL released 76% mycolic acids in the C50 size range plus 24% trehalose.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1976

Different degrees of morbidity, in the white mouse, induced by Nocardia brasiliensis, Nocardia asteroides and Nocardia caviae.

The respective degrees of morbidity induced by 6 strains each of Nocardia brasiliensis, N. asteroides and N. caviae were investigated by the method of inoculation in the plantar pad of the white mouse, using a suspension of these nocardiae at a concentration of 10 mg/0-1 ml., and inspecting the animals one month, two months and three months following inoculation. All of the strains of N. brasiliensis produced attack greater and more consistent than that of the other species, N. caviae and N. asteroides showing patterns of attack similar to each other, but substantially lower than those obtained with N. brasiliensis. The 6 strains of N. brasiliensis showed different rates of infection at different times of observation, but it was constantly high for all of them; on the other hand, the infectiousness of the different strains of N. caviae and N. asteroides was low, and there were no substantial differences between them. To sum up, these results with 6 strains of each species confirm those that were published in 1973 which dealt with only one strain of each species.

Animals↗