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1.
Khan  Z.U.  Neil  L.  Chandy  R.  Chugh  T.D.  Al-Sayer  H.  Provost  F.  Boiron  P. 《Mycopathologia》1997,137(3):159-163
A pilot study was undertaken to determine the occurrence and distribution of pathogenic nocardiae in Kuwaiti soil. A total of 102 soil samples collected from two localities were investigated by the paraffin bait technique. Nocardia asteroides was the only species isolated from 42 (41%) soil samples. None of the isolates fulfilled the criteria required for identification of N. farcinica or N. nova. Thirty one (73.8%) isolates showed equivalent growth at 45 °C and 35 °C, 17 (40.4%) isolates utilized acetamide for carbon and nitrogen requirements and 3 (7.1%) isolates showed delayed arylsulphatase activity. Only a solitary isolate was resistant to cefamandole. Soil samples originating from the Kuwait University Campus Shuwaikh, which were rich in humus/organic matter, were more productive for N. asteroides (67%) than the samples which were devoid of it but were mixed with crude oil (39%). Sand samples that lacked organic matter and crude oil samples were least productive of N. asteroides. These preliminary findings do not suggest that massive oil contamination of soil in the Ahmadi oil field area during the Gulf war promoted the natural occurrence of N. asteroides. However, isolation of N. asteroides in as many as 41% of the soil sample is a significant observation warranting further epidemiologic studies including its possible role in the operation desert storm sickness syndrome. This is the first report on the natural occurrence of N. asteroides in Kuwait. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

2.
A preliminary investigation of two methods of isolating pathogenic aerobic actinomycetes from a group of Sudanese soils was undertaken. By one method,Nocardia asteroides was isolated from 3 out of 4 soils. By the second method, two strains ofN. brasiliensis and three ofActinomadura madurae were recovered from 4 out of 10 soils. Both procedures seem to be advantageous for isolating pathogenic aerobic actinomycetes from soils.  相似文献   

3.
Immunodiffusion studies of some Nocardia strains   总被引:4,自引:0,他引:4  
Forty-three strains of Nocardia, one of Actinomadura and two of Nocardiopsis were studied using the comparative immunodiffusion technique. Three reference precipitation systems were employed: one represented Nocardia asteroides N10, one N. asteroides ATCC 19247, and one N. otitidis-caviarum ATCC 14629. One tight cluster was formed by the N. otitidis-caviarum strains and another tight cluster was formed by some of the N. asteroides strains studied. However, other strains of N. asteroides were distinct from the latter cluster. Furthermore, N. asteroides ATCC 19247, which is the type strain, differed from most ot the N. asteroides strains tested. Strains of the species N. asteroides, N. brasiliensis, N. farcinica and N. otitidis-caviarum were found to be closely related, while N. amarae strains differed slightly from this group. The strains referred to Actinomadura and Nocardiopsis were clearly distinct from the three Nocardia reference strains; nevertheless, three antigens common to these genera were revealed.  相似文献   

4.
Among the five species of pathogenic Nocardia, i.e., N. asteroides, N. brasiliensis, N. farcinica, N. nova and N. otitidiscaviarum, all strains of N. brasiliensis and N. farcinica showed resistance to an aminoglycoside antibiotic, kanamycin A, showing the MIC (minimum inhibitory concentration) values of more than 100 micrograms/ml. This species-specific difference in sensitivity was found to be explained by the production of an inactivation enzyme, aminoglycoside 3'-phosphotransferase APH(3'). Structural studies by mass and NMR spectroscopy on the inactivated substance produced by a cell-free extract of the Nocardia confirmed the conversion of kanamycin A to an inactive substance, kanamycin A 3'-phosphate. The MIC values of N. otitidiscaviarum and N. nova for kanamycin A, on the other hand, ranged from 0.78 micrograms/ml to 100 micrograms/ml, and both species were non-producers of APH(3'). Sensitivity to the antibiotic and APH(3') productivity of N. asteroides varied depending on the strain.  相似文献   

5.
Morphology--by growth phases-- was studied in the N. asteroides strain isolated from cows suffering from mastitis in Cuba. During the growth N. asteroides culture underwent a number of morphological cyclic changes; definite morphology was typical for each growth phase. There was a similarity between the structure of the surface N. asteroides and mycobacteria; cyclic changes in the structure of the membranes in nocardia were also shown.  相似文献   

6.
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.  相似文献   

7.
Abstract Nocardia asteroides complex organisms derived from human specimens between 1979 and 1992 were identified on the species level. Of 117 N. asteroides complex organisms, 34 (29%) were N. farcinica , 28 (24%) were N. nova , and 55 (47%) were N. asteroides sensu stricto . An analysis of the specimen sites from which the organisms were derived showed that isolates derived from blood, brain, or bone marrow were more likely to be N. farcinica than the other two species. A study of the virulence of ten strains of each species was undertaken, using a mouse model with intravenous inoculation. The 50% lethal doses (LD50) for N. farcinica were significantly lower than those of the other two species. LD50 values for N. nova and N. asteroides were not significantly different. The above data confirming the greater virulence of N. farcinica support the identification of species within the N. asteroides complex.  相似文献   

8.
Changes in membrane potential and conductance were studied in neurons of isolated sympathetic ganglia ofRana ridibunda during perfusion with cholinomimetics and cholinolytics. Activation of nicotinic (N) acetylcholine receptors by carbachol, suberyldicholine, and tetramethylammonium led to depolarization with an increase in conductance, whereas activation of muscarinic (M) acetylcholine receptors by perfusion with carbachol or 5-methylfurmethide, led to depolarization with a decrease or (less frequently) an increase in conductance. The M-cholinolytic atropine was shown to cause depolarization with an increase in conductance if perfusion with atropine was preceded by perfusion with carbachol.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 11, No. 5, pp. 475–482, September–October, 1979.  相似文献   

9.
Actinomycete infections in humans--a review.   总被引:10,自引:0,他引:10  
K P Schaal  H J Lee 《Gene》1992,115(1-2):201-211
Diseases caused by pathogenic aerobic and facultatively anaerobic actinomycetes differ considerably with respect to their etiology, pathogenesis, clinical appearance and epidemiology. Facultatively anaerobic (fermentative) actinomycetes may not only be involved etiologically in the three classical forms of cervicofacial, thoracic and abdominal actinomycoses, but also in infections of the female genital organs, the eye, the tissue adjacent to dental implantation elements and tooth extraction wounds. The species distribution of the fermentative actinomycetes isolated from these conditions varied to a certain, but characteristic, extent, as did the concomitant actinomycotic flora. The sex ratio reported for human Actinomyces infections (male:female = 3:1) appeared to be restricted to actinomycotic abscesses and empyemas. The prevailing pathogenic, obligately aerobic actinomycete species in Germany was found to be Nocardia farcinica followed by Nocardia asteroides. The comparatively high incidence of N. farcinica infections was chiefly due to the occurrence of nosocomial postoperative wound infections by this pathogen observed in two German hospitals. Besides surgical treatment, immunosuppressive treatment appeared to be the most common factor predisposing for nocardiosis. Recent observations strongly suggested that the spectrum of human nocardial infections in Germany has been changing, as regards the overall incidence, the prevalence of N. farcinica, the sex ratio, the mean age of patients, as well as the role of N. farcinica as a possibly important nosocomial pathogen.  相似文献   

10.
Formation of differentiation regulators of the A-factor group in representatives of Nocardia and Nocardia-like actinomyces: N. asteroides, N. brasiliensis, Amycolatopsis mediterranei and "Streptomyces listeri" was observed. The effect of the regulators of different nature (barbital, A-factor and B-factor) on biosynthesis of rifamycin B by A. mediterranei strains was studied. It was shown that the A-factor stimulated rifamycin B production in the adifferentiated low active variant isolated from a natural population of the active strain VNIIA 1713 of the rifamycin B-producing culture. B-Factor insignificantly inhibited biosynthesis of rifamycin B in the studied strains of A. mediterranei.  相似文献   

11.
From the total number of pesticides applied in the USSR, 18 are classified as being particularly dangerous compounds. Taking into account the self-purifying ability of the regional soils, arbitrary doses of these pesticides have been calculated for the administrative units of the Ukrainian SSR, the Moldavian SSR, and the water basin territories of the principal rivers in the region. This index is of greatest significance for arable and long-cultivated regions of the Crimea, Odessa, Kiev, Kherson, and Volynskiy, and for the Moldavian water basin territories of the Prut, the Dniester, and the Southern Bug.  相似文献   

12.
Culture filtrates of virulent Nocardia asteroides GUH-2 after growth in acetate minimal medium displayed an absorbance maximum at 320 nm. After isolation by polyamide extraction and anion chromatography, a UV-active compound with this absorbance was shown to be 2,3-dihydroxybenzoic acid (DHB) by nuclear magnetic resonance, gas chromatographic, and mass spectrometric techniques. DHB production under several culture conditions was quantified by a standard high-pressure liquid chromatography assay. Under iron deficiency conditions, N. asteroides GUH-2 excreted up to 11 mg of DHB per liter into the culture medium. No DHB was detected when N. asteroides GUH-2 was grown in an iron-rich medium. With the less virulent strain N. asteroides 10905, DHB was not found under any condition tested.  相似文献   

13.
Efficacy of the β-tubulin introns lenght polymorphism method (TBP) was used for Ukrainian bredeed flax cultivars genotyping. For this purpose, TBP data were compared with data produced using the two most effective species-specific SSR markers. Both methods were used to evaluate intra- and intercultivar flax polymorphism. For each cultivar, PIC data (Polymorphism Information Content) and the range of allele lenghts, as well as the number of allele phenotypes, were calculated using TBP and SSR markers. The dendrograms, built using Nei and Li’s similarity coefficient, differ for SSR and TBP markers. Most flax cultivars of Ukrainian selection were genetically heterogeneous. The TBP method was highly efficient for differentiation of flax genotypes versus SSR analysis.  相似文献   

14.
Distribution of HLA system leukocytic (tissue) antigens among the population of Carpathian genogeographic zone and among Ukrainian population of the native inhabitants of this region was studied, for the first time. The data characterizing the distribution, gene set and relationships of HLA antigens in A, B and C loci were obtained. It will be possible to discuss the distribution peculiarities of HLA system leukocytic antigens among the population of Carpathian zone after the work in all genogeographic zones of the Ukrainian SSR is completed and and the maps are published.  相似文献   

15.
P Boiron  D Stynen 《Gene》1992,115(1-2):219-222
A specific immunodominant 54-kDa antigen was purified from a culture filtrate of Nocardia asteroides by immunoaffinity chromatography. The chromatography column was prepared with immunoglobulin G obtained from sera from patients with lepromatous leprosy. Unbound solutes consisted of specific, partially purified N. asteroides antigens, primarily a 54-kDa band, accompanied by two others of 31 and 62 kDa. The Western blot (immunoblot) technique was applied to detecting the immunologic response to nocardiae in the serum of nocardiosis patients. Each of the serum samples from immunosuppressed or immunocompetent patients infected with N. asteroides reacted with the 54-kDa band, and two reacted with the 31- and 62-kDa bands. There was no reaction to either the 54- or the 31-kDa antigen with all serum samples obtained from patients with tuberculosis, except for one, with all serum samples obtained from patients with leprosy, or with all sera obtained from healthy controls. The partially purified 54-kDa antigen, specific for N. asteroides, was used as the immunogen to generate monoclonal antibodies (mAbs) and two mAbs were selected. As determined by Western blot, both mAbs reacted with the 54-kDa band. Using indirect immunofluorescence or enzyme immunoassay with whole N. asteroides micro-organisms, the mAbs did not react with N. asteroides cells. No cross-reactivity with mycobacterial antigens, either culture-filtrate antigens or tuberculin, was exhibited with any of the two mAbs. These mAbs are candidates to be used for the development of a sensitive and specific diagnostic test for nocardiosis.  相似文献   

16.
Mycolic acids from twelve Nocardia species were analyzed for structure using capillary gas chromatography and mass spectrometry. This high-resolution procedure permitted good separation of the trimethylsilyl (TMS) ether derivatives of mycolic acid methyl ester according to the total number of carbon and double bonds. The profiles of the mycolic acid molecular species were used as models to illustrate the difference in the structures of each species, even in the case of N. asteroides complex; N. asteroides, N. farcinica and N. nova. Although N. asteroides and N. farcinica had similar lengths of carbon skeleton, i.e., 51.9-53.7 was the average carbon number (Av.Nc.), they had different compositions of unsaturated acids. Mycolic acids from N. asteroides were composed of abundant saturated acids and less than 1% tetraenoic acids; mycolic acids from N. farcinica were composed of unsaturated acids, which were composed of abundant dienoic acids, 2-12% of tetraenoic acids and a trace of pentaenoic acids. In contrast, Av.Nc. of mycolic acids from N. nova were 55.7-56.3, which were relatively longer than those from N. asteroides or N. farcinica. Regarding the characteristics of the structure of alpha-branch, major components were C16:0 and C18:0 for N. asteroides 23206T, and C16:0 and C14:0 for N. farcinica 23157T, respectively. The presence of monounsaturated alpha-branch (C18:1 and C16:1) was characteristic of N. nova.  相似文献   

17.
Representative strains of the genus Nocardia, when grown on iron-deficient media, produce intracellular lipid-soluble, iron-binding compounds known as nocobactins. However, strains representing the 'rhodochrous' taxon fail to form such compounds. The formation of the nocobactins is completely repressed in bacteria grown on iron-sufficient media. Procedures for purifying the nocobactins are described. From their various properties (u.v. and visible spectra of the the ferri- and desferri-materials, mobility upon thin-layer chromatography, and dissociation patterns in HCl), they can be distinguished from the mycobactins (related compounds from mycobacteria) and divided into three main classes. The classes correspond to the three well-described species of the genus Norcardia: N. asteroides, N. brasiliensis and N. caviae. The correlation of the nocobactin data with previous results of conventional numerical taxonomy is high. Two strains of N. asteroides, however, did not produce nocobactins of the group type.  相似文献   

18.
The effects were investigated of allapinine, diterpene alkaloid on ionic currents in voltage-clamped trigeminal neurons and cardiomyocytes isolated from rats. Allapinine application was found to exert an inhibitory effect on inward tetrodotoxin-sensitive sodium currents without changing their voltage dependence. Potential differences between the mechanisms of antiarrhythmic action of diterpene alkaloids and standard antiarrhythmic substances are examined.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Institute of Plant Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Neirofiziologiya, Vol. 22, No. 2, pp. 201–206, March–April, 1990.  相似文献   

19.
Khan  Z.U.  Chugh  T.D.  Chandy  R.  Provost  F.  Boiron  P. 《Mycopathologia》1998,143(3):151-154
In this study, using the API-ZYM system, we have reported the enzyme profile of 42 soil strains and 2 clinical strains of Nocardia asteroides isolated locally. Of the 19 enzymes tested, only 7 were demonstrable in over 90% of the soil isolates. These included alkaline phosphatase, esterase lipase, leucine arylamidase, acid phosphatase, phosphohydrolase, α-glucosidase and β-glucosidase. In addition, β-galactosidase activity was demonstrated in all the strains by the O-nitrophenyl-β-D-galactopyranoside (ONPG) test. The enzymes which were not demonstrable in >95% of the strains included valine arylamidase, cystine arylamidase, trypsin, chymotrypsin, α-galactosidase, β-glucoronidase, N-acetyl-β-glucosaminidase, α-mannosidase and α-fucosidase. With the exception of valine arylamidase, which was lacking in all but one isolate, the enzyme profiles of the soil isolates were comparable with the clinical isolates of N. asteroides reported in previous studies. The reasons for this difference in the two sets of isolates is not clear. The study reinforces the view that specific differences in the enzymatic profiles of Nocardia species could be used for their rapid identification. However, more extensive studies are needed to establish the reproducibility of this method. To the best of our knowledge, this is the first study of the enzymatic profile of soil isolates of N. asteroides originating from a single geographic region. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

20.
Membrane proteins with a molecular weight of 290, 180, and 55 kDa were isolated using immunosorbent attached to sepharose and rabbit antibodies to cytoplasmic tetrodotoxin-sensitive protein from beef brain gray matter. A technique used for research into voltage-dependent sodium channels was applied to reconstruction of these proteins and investigation of toxin-dependent sodium flows through the lipoprotein membrane. Findings are interpreted as evidence of the similarity between cytoplasmic tetrodotoxin-sensitive protein and that of sodium channels at the cell membrane.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev; A. V. Palladin Institute of Biochemistry, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 21, No. 4, pp. 485–489, July–August, 1989.  相似文献   

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