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PubMedDate not supplied

Ukrainian National Collection of Microorganisms.

A list which describes microbial pools of the Ukrainian National Collection of Microorganisms created on the basis of the Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine is presented. Collection guarantees maintenance of over 3500 strains of microscopic fungi, yeasts, coryne- and nocardioforms, streptomycetes, methane-oxidizing and methylotrophic bacteria, bacilli, phytopathogenic and nitrogen-fixing bacteria, gram-positive catalase positive aerobic cocci, pseudomonads, lactic-acid bacteria and mycoplasmas. Over 250 type strains and over 300 strains of microorganisms useful for medicine, economy and biotechnology are maintained in the Collection.

Academies and Institutes↗
PubMed1996

Microorganisms as a tool of studying copper metal ions--induced changes in electrophysical cell properties.

Microorganisms are very sensitive to the effect of metal ions and a deficit or an excess of essential metal ions may induce some cell disturbances. The main objective of this research is to evaluate the effect of toxic metal ions. Doing that, the effects of metal ions on the electrophysical properties of the cell membrane, probed by electroorientational spectroscopic techniques and analysis of the electrophoretic mobility of cells have been chosen for investigation. The purpose of this work is to determine the optimal conditions of investigation of different kinds of microorganisms exposed to Cu. pH had a great influence on the electrophysical changes induced by Cu and this may be related to the speciation of the metal, according to its degree of hydroxylation. It will now be possible to compare the effects of toxic metal ions (Cd, Hg, Pb, etc..) or therapeutic metal ions (Pt, Ga, Ru, Ti, Sn, etc..) with those observed for Cu, in the conditions optimized by this study.

Bacteria↗
PubMed1996

Influence of immunoglobulin and interleukin 2 on the translocation of microorganisms from gut into blood.

The aim of this study was to influence the translocation of microorganisms and endotoxin from the gut of septic rats by the intravenous (i.v.) administration of immunoglobulin and interleukin 2. Acute infection was induced in all animals by an intraperitoneal bacterial challenge of 2 x 10(6) microorganisms (Ps. aeruginosa, E. coli, Kleb. pneumoniae). Immediately after the bacterial challenge control animals were given albumin i.v. whereas the experimental groups were given immunoglobulin or interleukin 2. A significant reduction of bacteria in the plasma of rats was observed in immunoglobulin treated animals (10,000 CFU/ml vs 450 CFU/ml). This was accompanied by an increase of plasma endotoxin of nearly 100% within the first 2 h. Interleukin 2 essentially did not change the bacterial count in comparison with albumin-treated control animals but reduced the endotoxin level in plasma up to tenfold. It is concluded that both immunoglobulins and interleukin 2 are involved in severe infections. Whereas immunoglobulins reduce bacterial translocation, interleukin 2 stimulates the elimination of endotoxin.

Animals↗
PubMed1997

RIFLE: rapid identification of microorganisms by fragment length evaluation.

Biological macromolecules represent a valuable source of information for the identification and phylogenetic classification of microorganisms. One of the most commonly used macromolecules for this task is the 16S rDNA. The WWW-based RIFLE system presented here supports large-scale identification tasks by comparing 16S rDNA restriction patterns to a database of restriction patterns derived from sequence databases. Computing efficiency and robustness against experimental errors are gained by employing a new distance measure for restriction patterns, the fragment length distance. Results from the application of the system to the identification of uncultured microorganisms associated with the seagrass halophila stipulacea show the reliability of the method.

Algorithms↗
PubMedDate not supplied

[The photometric determination of the antilysozyme activity of microorganisms].

The method for the determination of the antilysozyme activity (ALA) of microorganisms, based on the photometric determination of the residual activity of enzyme with the use of Micrococcus lysodeikticus test culture after the incubation of the strain under test and lysozyme, is proposed. The new method enhances the reliability of the determination of the ALA of microorganisms due to an increase in the accuracy of the quantitative determination of ALA. The elimination of the stage of interaction between the growing bacterial culture and lysozyme and the presence of the antilysozyme factor in the supernatant fluid confirm the constructive and secretory character of antilysozyme activity.

Bacteria↗
PubMedDate not supplied

[Factors in the persistence of opportunistic microorganisms in dysbacteriosis of the gastrointestinal tract].

The presence of correlation between the quantitative content of individual carboxylic acids and aromatic compounds of microbial origin in feces and the degree of the antagonistic activity of feces was proved in experiments on conventional laboratory rats receiving therapeutic doses of tetracyclin and pefloxacin for 8 days. Antagonistic activity was regarded as one of the factors of the colonization resistance of the intestine to the invasion of opportunistic microorganisms, and microbial metabolites studied in this work were regarded as factors contributing to the persistence of these microorganisms.

4-Quinolones↗
PubMedDate not supplied

[The creation and functions of the Depository of Microorganism Strains in the Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine].

The legislative and other standard acts regulating the functioning of the home depositories and the procedure of microorganism strains deposition when patenting the inventions in Ukraine have been developed and came in force. The depository created on the basis of the Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine to deposit nonpathogenic strains of microorganisms and to execute a number of service works in the field of microbiology and biotechnology began its activities (investigation, identification, certification, preservation of cultures, development of the methods of long-term preservation, toxico-biological evaluation of producers, delivery of strains, consultations, obtaining of information materials).

Academies and Institutes↗
PubMed1998

Air-borne microorganisms in the metropolitan area of Graz, Austria.

Urban and rural regions are affected by different microorganism loads depending on their structure and utilization. At 7 sampling sites in the metropolitan area of Graz, counts of airborne bacteria as well as yeasts and molds were conducted over a one-year period at two-week intervals. Bacteria and yeasts/molds counts in a village area to the South of Graz dominated by agriculture exceeded the corresponding counts in a suburban residential area fourfold (327 CFU/m3 air-bacteria) and twofold (185 CFU/m3 air-yeasts/molds) respectively. In the vicinity of a composting facility located in the same residential area, microorganism counts exceeded those of the neighboring "unaffected" area by 29% in the case of bacteria and by 54% in the case of yeasts/molds. At an industrial and business site with heavy traffic, the counts are twice that of the area affected by the composting facility (146 CFU/m3 for bacteria and 168 CFU/m3 for yeasts/molds). The proportion of Aspergillus fumigatus is highest in the village area with 23%, compared to 10% in the open land. 49% of the bacteria and 54% of the yeasts and molds can be shown on stages 4-6 of the Andersen-Volumetric-Sampler registering the respirable particle sizes.

Air Microbiology↗
PubMedDate not supplied

[A quantitative method of determining lecithinases and lipases in microorganisms].

The paper presents a method for quantitative assay of lecithinases and lipases in microorganisms. The method is based on the assessment of changes in the composition of lipid components of yolk media under the influence of corresponding enzymic systems of bacteria. The technique involved lipid extraction from yolk media after cultivation of the microorganisms tested, chromatographic separation by thin-layer chromatography on silicagel into individual fractions, development in iodine vapours and quantitative measurement of lipid components.

Bacteria↗
PubMed1998

Airborne microorganisms associated with grain handling.

There is substantial evidence that workers handling grain develop allergic respiratory symptoms. Microbiological contaminants are likely to be a significant contributing factor. Worker's exposure to microorganisms contaminating grain dust in the UK was therefore examined. Aerobiological studies were made when grain was being handled on farms and also during bulk handling of grain in dockside terminals. A quantitative and qualitative microbiological examination of the airborne grain dust was carried out. Samples of airborne grain dust were collected and viable bacteria, fungi and actinomycetes were grown, isolated and identified. It was found that workers handling grain or working close to grain at farms and docks were frequently exposed to more than 1 million bacteria and fungi per m3 air, and that airborne bacteria and fungi exceeded 10(4) per m3 air in all areas sampled. The qualitative examination of the samples showed that the predominant microorganisms present differed between freshly harvested grain and stored grain, but not between different types of grain.

Agricultural Workers' Diseases↗
PubMed1997

[Study of the relationship between the control of environmental microorganism and infection of patients with leukemia after trasplantation of bone marrow].

After the transplantation of bone marrow, patients with leukemia are easily infected by kinds of microorganism and die. In this paper, F-mice with the 60Co-gamma irradiation (maximum lethal dose) were transplanted bone marrow, then control the microorganism in the environment. Morever the laminar flow wards for the leukemia patient of bone marrow transplantation were designed according to the data combined with the clinic condition. There is no any infection in twelve patients with bone marrow transplantation from 1989 to 1993.

Animals↗
PubMed1983

Microorganisms as antineoplastic agents in CNS tumors.

In two patients, malignant tumors unexpectedly regressed following infections. I reviewed the extensive body of literature, both experimental and clinical, concerning the antineoplastic potential of bacteria and viruses. Substantial evidence exists to indicate that microorganisms may, by growing in or near tumors, completely or partially inhibit tumor growth, or alternatively may have no effect at all. In fact, oncolysis may occur only when a specific organism infects a specific tumor.

Adult↗
PubMed1976

Abnormal microorganisms and cell-mediated immunity in patients with intraoral cancer.

A substantial number of patients with intraoral malignant neoplasms have abnormal bacterial flora of skin, nasopharynx, and oropharynx, without a demonstrable relationship between tumor size, location, or degree of ulceration. Seventeen consecutive patients were studied to determine what relationship, if any, exists between the presence of abnormal microorganisms and the patients' immunological competence. Ten of 17 patients grew potentially pathogenic organisms, and all reacted to specific skin tests used to infer immunological competence. Thus, there appeared to be no relationship between cellular immunity and the presence of abnormal bacteria in patients with intraoral malignant neoplasms.

Bacteria↗
PubMed1997

Fluorescent brighteners: novel stains for the flow cytometric analysis of microorganisms.

Flow cytometry is a rapid method for measuring the optical properties of individual cells. The technique has found great utility in the study of mammalian cells, but microbiological applications have been more limited. We here show that UV-excited fluorescent whitening agents, in particular Tinopal CBS-X, are effective stains for both vegetative microbial cells and for spores of Gram-positive bacteria. Pretreatment of samples with ethanol speeds the staining process. Under favourable conditions, Tinopal CBS-X may be used to discriminate among organisms, a fact that may be useful when screening for a target microorganism against a high biological background.

Bacillus subtilis↗
PubMed1999

Variable selection and multivariate methods for the identification of microorganisms by flow cytometry.

BACKGROUND: When exploited fully, flow cytometry can be used to provide multiparametric data for each cell in the sample of interest. While this makes flow cytometry a powerful technique for discriminating between different cell types, the data can be difficult to interpret. Traditionally, dual-parameter plots are used to visualize flow cytometric data, and for a data set consisting of seven parameters, one should examine 21 of these plots. A more efficient method is to reduce the dimensionality of the data (e.g., using unsupervised methods such as principal components analysis) so that fewer graphs need to be examined, or to use supervised multivariate data analysis methods to give a prediction of the identity of the analyzed particles. MATERIALS AND METHODS: We collected multiparametric data sets for microbiological samples stained with six cocktails of fluorescent stains. Multivariate data analysis methods were explored as a means of microbial detection and identification. RESULTS: We show that while all cocktails and all methods gave good accuracy of predictions (>94%), careful selection of both the stains and the analysis method could improve this figure (to > 99% accuracy), even in a data set that was not used in the formation of the supervised multivariate calibration model. CONCLUSIONS: Flow cytometry provides a rapid method of obtaining multiparametric data for distinguishing between microorganisms. Multivariate data analysis methods have an important role to play in extracting the information from the data obtained. Artificial neural networks proved to be the most suitable method of data analysis.

Bacillus subtilis↗
PubMed1999

A simple chiral high-performance liquid chromatographic method to study the enantiomer-differentiating action of microorganisms. An assay with DL-tryptophan.

To investigate the 'enantiomer-differentiating' action of the microorganisms colonizing a phosphate-buffered DL-tryptophan solution, a novel chiral high-performance liquid chromatographic (HPLC) arrangement was developed and established. As the HPLC stationary phase, bovine serum albumin (BSA) bonded silica gel was used. In the function of the mobile phase, phosphate-buffered DL-tryptophan solution was applied. The composition of the eluate was monitored by an HPLC spectrophotometric detector. After injecting the assayed sample into the eluent stream, the content of each tryptophan enantiomer was evaluated either from the positive or negative responses of the HPLC detector. The validity and the performance of this novel approach were confirmed by applying another chiral HPLC device working with human serum albumin (HSA) bonded silica gel as the stationary phase and with 1-propanol containing phosphate buffer as the eluent.

Buffers↗
PubMed1980

Heterotrophic nitrification by intestinal microorganisms.

From studies of nitrate balance in man and analyses of fecal and ileostomy samples, the possibility that nitrite and nitrate are formed de novo in the intestine, possibly by heterotrophic nitrification has emerged. This proposition significantly alters our previous conceptions of man's exposure to nitrite and suggests that nitrite may play a role in the cause of intestinal cancer. Heterotrophic nitrification has been demonstrated in various microorganisms. Our work has shown that intestinal heterotrophic microbial isolates from man are able to oxidize nitrogenous compounds to nitrite. These isolates include both procaryotes and eucaryotes.

Actinomyces↗