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At least 1,207 records · Page 67Linked to original sources
PubMed1990

[Immunologic status in cattle naturally infected with the microorganisms Chlamydia trachomatis and Chlamydia psittaci].

In the present paper there is a description of immunological reactions in 12 to 14 months old bullocks, naturally infected by the microorganisms Chlamydia (Ch.) psittaci and Chlamydia trachomatis. In the course of infection by the above-mentioned microorganisms (chlamydia isolated from semen) without any clinical symptoms the activity of leucocytes and polymorphonuclear cells (PMN) in the peripheral blood is variable and the concentrations of serum immunoglobulins (IG) decrease. It has been demonstrated that the infection of bullocks by Ch. trachomatis increases the bacteria absorbing capacity of PMN cells (from 14.2 to 20.1), percent of phagocytic cells in the peripheral blood (from 13.0 to 26.5%). NBT reduction activity both in a spontaneous test (from 3 to 6) and in a stimulated test (from 8 to 12), and also myeloperoxidase activity (from 0.29 to 0.42). In these animals there were also recorded decreases (although not statistically significant) in the concentrations of serum IgG1, IgG2, IgA by about 10% and by about 30% in IgM. In Ch. psittaci-infected bulls leucocyte migration in the peripheral blood decreased (from 4.5 to 2.7 mm). PMN cell adherence (from 50 to 32), lysosome amount (from 0.63 to 0.35 mg per l) also decreased. In these bullocks decreases in the concentrations of serum Ig from 12.2 to 8.2 g per l in IgG1 and from 3.8 to 1.7 g per l in IgM were also proved.

Animals↗
PubMed1986

[Taxonomy and systematics of pathogenic microorganisms].

The modern state of the problem of the systematics of microorganisms is analyzed and the data on the taxonomy of bacteria belonging to the family Enterobacteriaceae are presented. The importance of studies on the taxonomy of microorganisms is emphasized. These studies play a vital role in the development of diagnostic preparations and techniques for the identification of infective agents, as well as in the realization of epidemiological surveillance. Much attention is given to the works of Soviet microbiologists, discussing such problems as the unification of the classification scheme of dysentery bacteria, the intraspecific taxonomy of Francisella tularensis, the systematic position of Allomonas and the antigenic scheme of Hafnia, included into Bergey's Determinative Bacteriology, edition IX (1984).

DNA, Bacterial↗
PubMed1989

A modified Brown and Hopps stain for identification of gram-positive and gram-negative microorganisms in glycol methacrylate-embedded tissues.

Plastic embedding is a recently developed technique that has been shown to be superior to conventional paraffin embedding in the histopathologic identification of microorganisms in tissue specimens. This report describes a modification of the Brown and Hopps stain for the differentiation of gram-positive and gram-negative microorganisms in 3-micron-thick plastic sections. This technique is easily performed and has a rapid turnaround time. This staining method permits a more precise histopathologic diagnosis of infectious agents than is possible in paraffin-embedded tissues.

Acrylates↗
PubMed1989

[A micromethod for the rapid detection of proteolytic activity of microorganisms].

The author has developed a micromodification of the rapid photoemulsion method for the detection of the microorganism proteolytic activity. The test is carried out on polystyrene plates, meat-peptone broth is used as the suspension fluid. Rectangular film strips are vertically placed into the wells, thus preventing false-negative reactions possible in case of an erroneous horizontal position of the film with the emulsion layer turned upwards if square or round film fragments are used. The proteolytic activities of 120 microorganism strains (95 of these hydrolyze gelatin) have been examined by the micromethod and the routine test with gelatin. The suggested test is 2-4-fold more rapid than the routine one used in investigations of the cultures slowly hydrolyzing gelatin. The fact that the test is carried out on the plates considerably reduces the nutrient medium and the number of laboratory glassware and helps obtain more accurate results.

Bacteria↗
PubMed1989

[Tinctorial properties of microorganisms isolated from blood].

Cultures isolated from human and animal blood have been examined in tests with 3% KOH solution; their sensitivities to various concentrations of sulfanol have been tested in order to specify the tinctorial characteristics of these cultures; antibiotic sensitivity of this group of microorganisms has been studied with the use of discs. The findings evidence that gram-variable nonspore-carrying aerobic bacilli isolated from human and animal blood should be referred to gram-positive microorganisms; their antibiotic sensitivity has been detected. The tests employed in the study may be rationally used for the identification of polychromic bacteria isolated from the blood.

Animals↗
PubMed1989

[A simplified method of counting microorganisms in studying human autoflora].

Formulae for the calculation of the count of microorganisms isolated from natural bacterial biocenoses of a child's body have been derived. The authors suggest a variant of simplified drip method for the computation of microorganism colonies in solid media. The described method helps cut down the nutrient media consumption at least 3-fold and is time-saving.

Colony Count, Microbial↗
PubMed1989

[The effect of drying on the content of nucleic acids and mutational changes in microorganisms].

The literary and own experimental data on the genetic apparatus changes in microorganisms after drying are reviewed. In the survived drying cells the total content of nucleic acids decreases, some amount of mainly high-molecule ribonucleic acid decomposes. The RNA isolation into the suspended medium is also observed in connection with the destructive processes in the cytoplasmic membrane and the decomposition of some intracellular structures. The dehydration of microbial cells violates the normal processes of DNA replication, and sometimes it leads to the conformational changes in molecule structure. In some cases the damage in the genetic apparatus causes the mutation changes of microorganisms. This should be taken into account in experiments where lyophilized cultures are used.

DNA Replication↗
PubMed1989

[Gardnerella vaginalis: role of a microorganism emerging as a vaginopathic agent and its placement in the vaginal microbial ecosystem].

In this review the role of an emergent pathogen, Gardnerella vaginalis (G. vaginalis), as aetiologic agent of the so called "non specific vaginitis" is systematically evaluated. The microorganism is described in its morphological, biochemical and virulence aspects in the framework of the complex vaginal ecosystem. The diagnostic criteria of the disease as well as a possible association of G. vaginalis with other vaginal bacteria, especially anaerobes, in the aetiology of the disease, are discussed. Literature data on prevalence and incidence of G. vaginalis in different population groups are integrated by more recent investigations of the Authors on prevalence and carriage of microorganism in a group of outpatients in Italy.

Adolescent↗
PubMed1989

[Quantitative patterns of the thermal inactivation of microorganisms as a basis for obtaining high-quality vaccinal preparations].

The model of the thermal inactivation of microorganisms is presented. This model permits the explanation of all existing kinetic dependencies relating to the death of microorganisms, the restoration of sublethal damages, the influence of the medium and the temperature of incubation on the process of the production and control of vaccinal preparations.

Bacterial Physiological Phenomena↗
PubMed1989

Biochemical determinants of aminoglycoside resistance in Gr- microorganisms isolated from urocultures.

The investigation was focused on 60 strains of Gr- microorganisms isolated from urocultures and resistant to gentamicin and/or amikacin. Resistance evaluation by the method of Bauer--Kirby with respect to 7 aminoglycoside aminocyclitols (streptomycin, spectinomycin, kanamycin, gentamicin, tobramycin, sisomicin, netilmicin and amikacin) as well as determination of minimal inhibitory concentrations revealed that the most frequently occurring resistance phenotype was streptomycin kanamycin gentamicin sisomicin tobramycin (91.66% tested microorganisms). Approximately 50% of all tested organisms were found to be susceptible to netilmicin. Assays for aminoglycoside-modifying enzymes using 32P ATP and 14C ATP confirmed APH(3')(5")--I and AAD(2") as resistance determinants regarding 4,6-substituted deoxystreptamines. Acetyltransferase determination by the method of Shannon and Phillips and that by van de Klundert et al. most frequently assumes for the formation of AAC(3)-II and AAC(3)-I. Assays utilizing radioactive labels in amikacin-resistant strains determine the enzymes APH(3') and AAD(2")-II.

Aminoglycosides↗
PubMedDate not supplied

[Clustering of oligotrophic microorganisms on the basis of their antibiotic resistance and dynamic membrane characteristics].

Some oligotrophic microorganisms were characterised in terms of their resistance against a broad spectrum of antibiotics and certain dynamic parameters of membranes obtained by analysing the EPR and NMR spectra. The oligotrophic bacteria differed in these characteristics from eutrophic microorganisms. The oligotrophic bacteria were subdivided into 3-4 subgroups different in many of the studied parameters. A new chemotaxonomic approach was proposed for the oligotrophic bacteria basing on the analysis of antibioticograms.

Anti-Bacterial Agents↗
PubMed1985

[Allomonas--a new group of microorganisms of the Vibrionaceae family. Allomonas enterica in seawater and various hydrobiotas].

Bacteriological investigations made in the Black Sea, the Sea of Azov and the Sea of Japan have revealed that Allomonas enterica are widely spread in sea water and hydrobionts. The prevalence of these microorganisms in biotopes with unfavorable sanitary characteristics and their high correlation with the main indicator microorganisms suggest their importance as indicators, and a high percentage of seafood contaminated with Allomonas necessitates their study as possible causative agents of toxinfections.

Animals↗
PubMed1985

Microorganisms in semen used for artificial insemination.

The effect of freezing semen in a cryopreservative media consisting of egg yolk glycerol with or without erythromycin was tested for its effect on the viability of microorganisms present in donor semen and on sexually transmitted pathogens seeded into semen. All donor semen contained two or three species of microorganisms that could be considered skin flora. Five of ten donor semen specimens contained Ureaplasma urealyticum that was not affected by either freezing or antimicrobial treatment. Some strains of Neisseria gonorrhoeae, when seeded into semen, survived all conditions except freezing in egg yolk glycerol containing erythromycin. Chlamydia trachomatis was erradicated when erythromycin was present in the cryopreservative. There was no detectable effect of any treatment tested on the survival of herpes simplex virus.

Adult↗
PubMed1985

[Taxonomic identification of gram-negative nonfermenting microorganisms in environmental research].

The scheme for the identification of Gram-negative nonfermenting microorganisms is proposed. The scheme comprises the most important key signs, such as the cytochrome oxidase reaction determined by the method of Gaby and Hadley, the oxidation/fermentation test, maltose oxidation and motility, as well as additional key signs, among them gelatinase activity, the oxidation of 10% lactose, nitratase activity with the liberation of free nitrogen, the utilization of the sources of carbon and energy (glucose and sodium acetate) in limited media containing ammonium salts and nitrates as the sources of nitrogen. Additional tests for the identification of nonfermenting microorganisms similar in their main key signs are also recommended.

Bacteriological Techniques↗
PubMed1988

[Oxygen regulation of nitrogen metabolism in microorganisms].

Oxygen is one of the most important environmental factors for microorganisms. Many metabolic reactions of aerobic or facultative anaerobic bacteria are influenced by varying oxygen concentrations. A lot of enzyme reactions in respiration processes, catabolism, anabolism and gene expression depend upon oxygen. Other enzymes such as nitrogenase or hydrogenases can be inhibited by increasing oxygen levels. Also complex metabolic processes including anaerobic respiration and fermentations are regulated by oxygen. Finally toxic oxygen derivatives have to be eliminated by living cells to overcome damage of cell constituents. In this way also bacteria which are included into the nitrogen cycle in the nature are influenced by oxygen. The different strategies of microorganisms to protect their nitrogenases for oxygen inactivation and the regulation of dissimilative nitrate reduction by oxygen are demonstrated in detail.

Bacteria, Aerobic↗
PubMed1988

Disintegration of microorganisms.

The most common methods for the large-scale disintegration of microorganisms are high-pressure homogenization and wet milling. The most-used homogenizer is produced by Manton Gaulin and the common ball mill is the Dyno-Mill. Other manufacturers are now producing similar equipment (e.g., Rannie homogenizers and Netzsch ball mills). However, only relatively limited information on these systems has been published so far. An additional system that might become available for large-scale disintegration is microfluidization. When coming to choose optimal equipment and conditions for cell disintegration, it might be useful to consider some relevant topics that were compiled by the Retsch company for particle disruption and are presented, with modification, in Table XIII. Obviously, the importance of the above points will vary in different processes, but all of them should be considered in any biotechnological large-scale application. It is important to realize that although the mechanical disintegration methods are of general use, it is essential to define the optimal disintegration conditions for each microorganism and/or product. As a starting point, the published data for a similar product should be consulted. This should be followed by laboratory-scale experiments carried out with equipment and conditions that can be easily scaled up.

Cell Fractionation↗
PubMed1988

[Microorganisms isolated from urinary tract infection and their beta-lactamase production and evaluation of clinical efficacy of sulperazone].

Clinical survey of microorganisms isolated from urinary tract infection (UTI) was carried out at the four major hospitals in Mie Prefecture from May to July, 1987, and production of beta-lactamase of the microorganisms was determined by the acidimetric method, "beta-checker". Among the total of 460 strains isolated from urine samples, 135 of gram positive cocci and 325 of gram negative rods were contained. Sixty percent of the gram negative rods and 14% of gram positive cocci produced beta-lactamase. Pseudomonas aeruginosa, E. coli and Serratia marcescens were representative organisms which produced beta-lactamase. Acinetobacter, Klebsiella, Enterobacter and Citrobacter species produced beta-lactamase at a higher rate but those were not so frequently isolated. In the sensitivity test to Sulperazone, the representative organisms isolated from urine, as a whole, had a sensitivity of 74% and E. coli, Klebsiella, S. epidermidis and Pseudomonas aeruginosa were highly sensitive, while Enterobacter cloacae and Serratia marcescens showed low sensitivity. The clinical efficacy of Sulperazone was evaluated in 26 patients with complicated UTI. Overall effectiveness rate and eradication rate of beta-lactamase production organisms were 73.1 and 63%, respectively. Sulperazone is concluded to be a useful antibiotic for treating complicated UTI induced by beta-lactamase production organisms from the point of microbiology and safety.

Adult↗