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1.
During the last two decades, nontuberculous mycobacteria (NTM) have gained in importance but there is still a paucity of data, particularly for environmental isolates. We studied, over a period of two years, the spatio-temporal features of NTM isolates obtained from different environmental sources in Wardha district, India. A total of 1398 samples (699 each of soil and water) were tested and 170 (12.2%) yielded NTM isolates, including 123 from soil and 47 from water samples. Out of 170 NTM isolates, 107 (63%) belonged to potentially pathogenic mycobacteria (PPM) and 63 (37%) to the less pathogenic mycobacterial (LPM) group. Overall, maximum isolation was obtained in rainy season (20.3%) followed by winter (13.5%), post rainy (8.7%) and summer seasons (5.8%). Mycobacterium fortuitum, Mycobacterium gordonae and Mycobacterium avium complex (MAC) were common isolates followed by Mycobacterium flavescens, Mycobacterium scrofulaceum, Mycobacterium simiae and Mycobacterium marinum. From soil, isolation of NTM was highest from grounds used for community gatherings (42.8%) followed by soil from residential premises (27.7%) and near the wells (26.0%). From drinking water sources, highest NTM isolation was obtained from wells (15.4%) followed by treated water tanks (6.9%), household receptacles (6.3%), hand pumps (5.6%) and tap water supply (3.5%). Isolation from natural canal water was 6.6%, while from drainage and waste water ponds isolation was 8.3%. The results of the study revealed that in Wardha district, NTM are present both in the soil and drinking water. As NTM can be pathogenic, particularly in immune-compromised individuals, these can be of potential risk to the human population.  相似文献   

2.
A simplified protocol for routine total DNA isolation from salmonid fishes   总被引:20,自引:0,他引:20  
An efficient total DNA isolation protocol, suitable for routine population genetic screening purposes is described. This phenol based extraction can utilize fresh, frozen or ethanol preserved tissues.  相似文献   

3.
An improved, simplified method for the purification of recombinant, tagged DnaA proteins is described. The presented protocol allowed us to purify soluble DnaA proteins from two different bacterial species: Helicobacter pylori and Streptomyces coelicolor, but it can most likely also be used for the isolation of DnaA proteins from other bacteria, as it was adapted for Mycobacterium tuberculosis DnaA. The isolation procedure consists of protein precipitation with ammonium sulphate followed by affinity chromatography. The composition of the buffers used at each purification step is crucial for the successful isolation of the recombinant DnaA proteins. The universality of the method in terms of its application to differently tagged proteins (His-tagged or GST-tagged) as well as different properties of purified proteins (e.g., highly aggregating truncated forms) makes the protocol highly useful for all studies requiring purified and active DnaA proteins.  相似文献   

4.
Procedures are described for the large-scale isolation of purified Na,K-ATPase (EC 3.6.1.3) from frozen lamb kidney outer medulla and for the separation of its two protein subunits by hydroxyapatite chromatography in sodium dodecyl sulfate (SDS). The methods described permit the routine isolation of up to 800 mg of purified Na,K-ATPase in one week, which can subsequently be separated into 500 mg of mr = 95,000 catalytic subunit and 200 mg of glycoprotein with four SDS-hydroxyapatite column runs.  相似文献   

5.
ABSTRACT. We describe the isolation of a mycobacterium from Acanthamoeba castellanii strain Ma (ATCC®50370?). The mycobacterium resides within vacuoles of A. castellanii, can be cultured by routine methodologies, and is a member of the Mycobacterium avium complex. Previously unrecognized mycobacterial endosymbionts are likely common among strains of Acanthamoeba housed at culture collections.  相似文献   

6.
Sved JA 《Genetics》1981,97(1):197-215
It is proposed that mating behavior is normally determined by independent genetic systems in the male and female. A specific model is put forward in which mating behavior is determined by additive gene contributions in both sexes, and the strength of mating attraction is maximized when mating "scores" in the two sexes are equalized. This type of model, which may be described as a "facilitation" model, is related to models proposed by a number of authors. It is pointed out that a second class of models exists, "avoidance" models, and that these, although less tractable analytically, could be more realistic.-An organism is assumed to be divided into two strains, and selection is introduced through lethality or sterility of the hybrid (postmating isolation). The selective tendency for divergence of mating behavior in one sex is then shown to be proportional to the amount of divergence that already exists in the opposite sex, multiplied by a quantity that can be described as the heritability of mating attraction. The situation in which no initial divergence exists in either sex constitutes an equilibrium that is unstable, but one that requires substantial deviations before any selective progress can be made. Thus, the evolution of premating isolation to reinforce postmating isolation may be an inefficient process. The process would occur much more efficiently if some initial chance divergence in mating behavior occurred during the period in which postmating isolation evolved.  相似文献   

7.
A procedure for the isolation of a crude enzyme preparation of esterases fromMycobacterium phlei was worked out. The procedure consists in breaking cells in 1% KCl by ultrasonication, ultracentrifugation at 40,000 r.p.m. and isolation of acetone and ether dried enzyme preparation. Specific activity increased 2.8-fold after completion of the procedure. Esterases fromMycobacterium phlei were separated on Sephadex of G series to two enzymes with different substrate specificity. The first enzyme, acetic ester acetyl-hydrolase (E.C. 3.1.1.6) was found to be relatively specific for ethylacetate, the second, carboxylic ester hydrolase (E.C. 3.1.1.1) for ethylbutyrate and tributyrine. Preparations of both enzymes were made from the crude extracts of cells and from a mixture of macromolecular compounds isolated from the culture filtrate ofMycobacterium phlei.  相似文献   

8.
A remarkable outer cell-wall thickening (up to 1.5 m) was observed on septate hyphae obtained from pus collected from multiple abscesses of a 25-year-old female patient. Ultrastructural examination of the hyphae showed a thick electron dense layer of microfibrillar material surrounding the electron transparent cell wall. The organism was able to grow only on hypertonic media upon initial isolation but on later subculture it grew on normal isotonic media. The thick microfibrillar material diminished progressively upon subculture but could be demonstrated in 7 day secondary cultures in isotonic liquid medium. There, microfibrillar bridges appeared to bind hyphae together. The observations suggested that this microfibrillar material was a true extracellular component. The immunological status of the patient was not examined, but her 10 year history of multiple mycotic abscesses and dermatophytoses suggested some abnormalities.  相似文献   

9.
Mycobacterium szulgai, described for the first time in 1972, is a rare human pathogen that mainly causes pulmonary non-tubercular mycobacteriosis. We report its isolation and identification from a bronchoalveolar lavage specimen by hsp65 gene sequencing analysis in an HIV-positive patient with non-Hodgkin's lymphoma.  相似文献   

10.
The isolation and properties of a desoxyribonucleoprotein of the rat liver cell nucleus are described. This material consists of DNA (desoxyribonucleic acid) bound to the residual chromosomal protein by what appear to be covalent linkages. Lipide is present, but can be removed by extraction in lipide solvents prior to isolation of the nucleoprotein, without much change in the physical properties of the latter. The nucleoprotein in question forms elastic, recoilable gels in molar saline at pH 7.0 or in water at pH 8.0 to 10.0 or even higher, which are similar to those that can be obtained from whole nuclei. The effects of x-rays, heat, and enzymes on the nucleoprotein are discussed, and the composition of the protein component is investigated. The latter contains an "occult" protein that can be liberated by heating in 0.1 N HCl. A study of the enzymatic degradation of the desoxyribonucleoprotein has been made, with the aim of attempting the isolation of small polynucleotide fragments attached to amino acids or short peptides that might be useful in characterizing the mode of attachment of the desoxyribonucleic acid to the protein in the desoxyribonucleoprotein. Evidence is presented indicating that such products can be isolated through the use of electrophoresis on paper.  相似文献   

11.
Benzalkonium chloride (BC) is an unreliable disinfectant. A matched case-control study and environmental investigation were conducted to determine the cause of and risk factors for a cluster of postinjection abscesses at a private medical clinic where BC was used as a disinfectant. Twenty-eight case-patients who had an abscess at the injection site were matched with 126 control patients who had received an intramuscular injection at the clinic on the same day. Risk factors for abscess development in a multivariable logistic model were corticosteroid injection and being female. All case-patients had received a corticosteroid injection from a multidose vial. Cultures of abscesses from 20 of 23 case-patients grew Pseudomonas aeruginosa. Cultures of BC prepared at the clinic also grew P aeruginosa, suggesting that BC was the source of infection. Injection site cleaning with BC did not appear to be the route of infection since use of BC at the time of injection was not associated with abscess development. A more likely route of infection was injection of contaminated corticosteroid from multidose vials that could have been inoculated with pseudomonads via needle puncture after vial septa were wiped with contaminated BC. Benzalkonium chloride should not be used to clean injection vial septa or injection sites.  相似文献   

12.
Mycobacterium malmoense was isolated from a soil sample, and biological, biochemical, antigenic, and genetic characteristics of the isolate were described. This is the first report of isolation of this organism in Japan.  相似文献   

13.
A crude outer-membrane protein (OMP) preparation from a strain of Bacteroides fragilis, grown in supplemented brain-heart infusion broth, was tested for its protective effect against subcutaneous infection in mice. Immunization with six doses, each of 100, 150 or 200 g OMP preparation, gave some protection: abscesses completely disappeared 15 to 22 days after immunization. In non-immunized animals and animals immunized with doses of 10, 20, 40 or 80 g each, well demarcated abscesses were seen beyond day 22 post-immunization. Although crude OMP elicited good antibody response, with maximum titres on day 4 post-immunization, high titres could not be associated with healing of the abscesses.  相似文献   

14.
AIM: The aim of this study was to further characterize a bacterial culture (VUN 10,010) capable of benzo[a]pyrene cometabolism. METHODS AND RESULTS: The bacterial culture, previously characterized as a pure culture of Stenotrophomonas maltophilia (VUN 10,010), was found to also contain another bacterial species (Mycobacterium sp. strain 1B), capable of degrading a similar range of PAH substrates. Analysis of its 16S rRNA gene sequence and growth characteristics revealed the strain to be a fast-growing Mycobacterium sp., closely related to other previously isolated PAH and xenobiotic-degrading mycobacterial strains. Comparison of the PAH-degrading characteristics of Mycobacterium sp. strain 1B with those of S. maltophilia indicated some similarities (ability to degrade phenanthrene and pyrene), but some differences were also noted (S. maltophilia able to degrade fluorene, but not fluoranthene, whereas Mycobacterium sp. strain 1B can degrade fluoranthene, but not fluorene). Unlike the S. maltophilia culture, there was no evidence of benzo[a]pyrene degradation by Mycobacterium sp. strain 1B, even in the presence of other PAHs (ie pyrene) as co-metabolic substrates. Growth of Mycobacterium sp. strain 1B on other organic carbon sources was also limited compared with the S. maltophilia culture. CONCLUSIONS: This study isolated a Mycobacterium strain from a bacterial culture capable of benzo[a]pyrene cometabolism. The Mycobacterium strain displays different PAH-degrading characteristics to those described previously for the PAH-degrading bacterial culture. It is unclear what role the two bacterial strains play in benzo[a]pyrene cometabolism, as the Mycobacterium strain does not appear to have endogenous benzo[a]pyrene degrading ability. SIGNIFICANCE AND IMPACT OF THE STUDY: This study describes the isolation and characterization of a novel PAH-degrading Mycobacterium strain from a PAH-degrading culture. Further studies utilizing this strain alone, and in combination with other members of the consortium, will provide insight into the diverse roles different bacteria may play in PAH degradation in mixed cultures and in the environment.  相似文献   

15.
多重PCR方法特异性鉴定卡介苗菌株多糖核酸的初探   总被引:1,自引:0,他引:1  
与结核分枝杆菌H37Rv菌株进行比较,BCG菌株可找到一个特殊的缺失片段RD1,它存在于所有有毒分枝杆菌中,而在所有的卡介苗菌株中均缺失。应用多重PCR方法检测RD1区的存在与否,可以区别BCG和其它有毒的分枝杆菌。卡介菌多糖核酸来源于卡介菌,检测成品中DNA是否含有RD1区,能特异性地鉴别该制品。结果显示牛分枝杆菌标准株和结核分枝杆菌H37Rv存在RD1区;而卡介菌多糖核酸注射液和国内皮内注射用BCG疫苗生产用菌株扩增产物一致,提示均缺失RD1区。因此,这种多重PCR方法适用于卡介菌多糖核酸注射液的特异性鉴别试验。  相似文献   

16.
Between May, 1972 and February, 1978, six cases of paratuberculosis (Johne's Disease) caused by Mycobacterium paratuberculosis were diagnosed in free-ranging Rocky Mountain bighorn sheep (Ovis canadensis) and one Rocky Mountain goat (Oreamnos americanus) on or near Mt. Evans in Colorado. Diagnosis of paratuberculosis was based on gross and histopathologic examination of the animals and by isolation of M. paratuberculosis from three sheep and the goat. The clinical signs and pathologic changes seen in the bighorn sheep resembled those described in cattle, while the lesions in the goat were similar to those described for domestic sheep and goats.  相似文献   

17.
18.
It was the aim of the present communication to find a simple test for a reliable discrimination ofMycobacterium bovis BCG fromMycobacterium tuberculosis. A total of 26 BCG strains, out of them 10 Czechoslovak strains (2 lyophilized cultures of BCG of different batch, 6 strains isolated from abscesses of children after BCG-vaccination and 2 strains from fatal cases after BCG-vaccination) and 16 strains obtained from foreign laboratories, were used. Of the tested characteristics a combination of 3 tests, sensitivity to 1 μg of 2-thiophene carbonylhydrazide (TCH), activity of 3 acylamidases (urease, nicotinamidase and pyrazinamidase) and a quantitative nitrate test, was found to be most advantageous. The Czechoslovak strains ofMycobacterium bovis BCG were fully sensitive to TCH, of the 3 acylamidases mentioned above only urease was positive and nitrate was reduced only little or not at all. On the other hand, strains ofMycobacterium tuberculosis were always resistant to TCH, had positive urease, nicotinamidase and pyrazinamidase and reduced nitrate very intensively.  相似文献   

19.
B Laroche  Y Homsy  G Perreault  I Laberge 《CMAJ》1979,121(2):184-187
One child with a pure perinephric abscess and three with renal abscesses, one of which had perinephric extension, are described. All presented with a long course of subacute infection leading to localizing symptoms or signs in the flank. The diagnosis was confirmed by radiologic examination. All the abscesses were surgically drained at various intervals after diagnosis, while the patients were receiving antibiotic therapy. Salvage of renal function was possible in all cases. A rational approach to the diagnosis and management of such abscesses is emphasized.  相似文献   

20.
The open-ended study of the International Working Group on Mycobacterial Taxonomy is an ongoing project to characterize slowly growing strains of mycobacteria that do not belong to well-established or thoroughly characterized species. In this fourth report we describe two numerical taxonomic clusters that represent subspecies or biovars of Mycobacterium simiae, one cluster that encompasses the erstwhile type strain of the presently invalid species "Mycobacterium paraffinicum," one cluster that is phenotypically very similar to Mycobacterium avium and Mycobacterium intracellulare but may be a separate genospecies, one cluster that appears to be phenotypically distinct from M. avium but reacts with a nucleic acid probe specific for M. avium, and three tentatively defined clusters in proximity to a cluster that encompasses the type strain of Mycobacterium malmoense. Of special practical interest is the fact that one of the latter three clusters is composed of clinically significant scotochromogenic bacteria that can be misidentified as the nonpathogenic organism Mycobacterium gordonae if insufficient biochemical tests are performed.  相似文献   

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