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  1. Article: A model for testing drug susceptibility of Pseudomonas aeruginosa and Staphylococcus aureus grown in biofilms on medical devices.

    Kétyi, I

    Acta microbiologica et immunologica Hungarica

    1995  Volume 42, Issue 2, Page(s) 215–219

    Abstract: UV-sterilized polyethylene rings infected with Pseudomonas aeruginosa or with Staphylococcus aureus were implanted into artificial wounds of mice. During 5 days incubation biofilm was formed on the plastic surfaces. To determine the Minimal Bactericidal ... ...

    Abstract UV-sterilized polyethylene rings infected with Pseudomonas aeruginosa or with Staphylococcus aureus were implanted into artificial wounds of mice. During 5 days incubation biofilm was formed on the plastic surfaces. To determine the Minimal Bactericidal Dose on sessile bacteria, rings with biofilm were removed and incubated in Luria broth containing serial dilutions of different antibiotics. Parallel, the sensitivities of planktonic phase organisms were also determined using cells grown in broth. The biofilm mode of growth strongly reduced the sensitivity of the strains against most of the antibiotics used, especially against polymyxin B. On the other hand, beta-lactam type antibiotics were equally effective against bacteria both in the sessile and planktonic phase of growth.
    MeSH term(s) Animals ; Anti-Bacterial Agents/pharmacology ; Biofilms/growth & development ; Equipment and Supplies ; Mice ; Microbial Sensitivity Tests ; Pseudomonas aeruginosa/drug effects ; Pseudomonas aeruginosa/physiology ; Specific Pathogen-Free Organisms ; Staphylococcus aureus/drug effects ; Staphylococcus aureus/physiology
    Chemical Substances Anti-Bacterial Agents
    Language English
    Publishing date 1995
    Publishing country Hungary
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 918256-1
    ISSN 1588-2640 ; 1217-8950
    ISSN (online) 1588-2640
    ISSN 1217-8950
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: Biofilms produced by Pseudomonas aeruginosa and by Staphylococcus aureus on model medical devices.

    Kétyi, I

    Acta microbiologica et immunologica Hungarica

    1995  Volume 42, Issue 2, Page(s) 221–227

    Abstract: Polyethylene, teflon, tygon, polypropylene, silicon rubber, and rubber tubes or rings contaminated with Pseudomonas aeruginosa or Staphylococcus aureus were implanted subcutaneously into mice. After 5 days the colony forming units developing on, and ... ...

    Abstract Polyethylene, teflon, tygon, polypropylene, silicon rubber, and rubber tubes or rings contaminated with Pseudomonas aeruginosa or Staphylococcus aureus were implanted subcutaneously into mice. After 5 days the colony forming units developing on, and attaching to them were determined. The highest numbers of bacteria were observed on rubber and silicon rubber, polyethylene was next in order, while significantly lower values were obtained on teflon and on tygon and polypropylene. Rubber devices were better colonized after heat than after UV sterilization. The number of bacteria rose further, if the already used rubber implant was resterilized, recontaminated and reimplanted. The model seems suitable to test the development of bacterial biofilms on different materials pretreated in different manners.
    MeSH term(s) Animals ; Biofilms/growth & development ; Equipment and Supplies ; Mice ; Plastics ; Pseudomonas aeruginosa/physiology ; Rubber ; Specific Pathogen-Free Organisms ; Staphylococcus aureus/physiology ; Sterilization ; Ultraviolet Rays
    Chemical Substances Plastics ; Rubber (9006-04-6)
    Language English
    Publishing date 1995
    Publishing country Hungary
    Document type Comment ; Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 918256-1
    ISSN 1588-2640 ; 1217-8950
    ISSN (online) 1588-2640
    ISSN 1217-8950
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Effectiveness of antibiotics on the autochthonous Escherichia coli of mice in the intestinal biofilm versus its planktonic phase.

    Kétyi, I

    Acta microbiologica et immunologica Hungarica

    1994  Volume 41, Issue 2, Page(s) 189–195

    Abstract: The effectiveness of antibiotics was tested on the autochthonous Escherichia coli in biofilm mode of growth in large bowel pieces as well as on the predominant faecal E. coli isolated from the same SPF mice in planktonic phase of growth. Aminoglycoside ... ...

    Abstract The effectiveness of antibiotics was tested on the autochthonous Escherichia coli in biofilm mode of growth in large bowel pieces as well as on the predominant faecal E. coli isolated from the same SPF mice in planktonic phase of growth. Aminoglycoside antibiotics, chloramphenicol, oxytetracycline, erythromycin and lincomycin-clindamycin treatment had a very limited effect in the intestinal biofilm. Surprising ineffectiveness was found with polymyxins: polymyxin B showed a Minimal Bactericidal Dose of 0.78 microgram in planktonic phase, while it was 400 micrograms for E. coli incorporated in the biofilm matrix. In contrast to the above groups of antibiotics, the beta-lactam drugs were effective both in the biofilm and in the planktonic phase growth of E. coli and their derivatives with broad or broader spectrum exerted an increased biofilm activity. Polymyxin B showed no sign of penetration into the colonic mucus, but on the other side ampicillin concentrated about three-four times in the intestinal matrix.
    MeSH term(s) Aminoglycosides ; Animals ; Anti-Bacterial Agents/pharmacokinetics ; Anti-Bacterial Agents/pharmacology ; Bacterial Adhesion ; Biofilms ; Colon/metabolism ; Colon/microbiology ; Escherichia coli/drug effects ; Escherichia coli/growth & development ; In Vitro Techniques ; Mice ; Microbial Sensitivity Tests ; Mucus/metabolism ; Mucus/microbiology ; Specific Pathogen-Free Organisms
    Chemical Substances Aminoglycosides ; Anti-Bacterial Agents
    Language English
    Publishing date 1994
    Publishing country Hungary
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 918256-1
    ISSN 1588-2640 ; 1217-8950
    ISSN (online) 1588-2640
    ISSN 1217-8950
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Antibiotikumok hatékonysága SPF egerek autochton Escherichia coli intestinális populációjára és planktonikus fázisú izolátumaira.

    Kétyi, I

    Orvosi hetilap

    1993  Volume 134, Issue 8, Page(s) 405–408

    Abstract: Representatives of different groups of antibiotics were tested on the autochtonous Escherichia coli of mice being in biofilm mode of growth, as well as on their isolates in planktonic phase. Aminoglycoside antibiotics, chloramphenicol, oxytetracycline, ... ...

    Title translation Effect of antibiotics on autochtonous intestinal E. coli population in SPF mice and on planktonic phase isolates.
    Abstract Representatives of different groups of antibiotics were tested on the autochtonous Escherichia coli of mice being in biofilm mode of growth, as well as on their isolates in planktonic phase. Aminoglycoside antibiotics, chloramphenicol, oxytetracycline, erythromycin, lincomycin-clindamycin, and polymyxins showed a very reduced effectivity on Escherichia coli embedded in the biofilm matrix. On the other hand, beta-lactam antibiotics were equally effective both for sessile and planktonic bacteria. Derivates with broader, or broad spectra showed an increased biofilm activity. Testing the possibilities of penetration or concentration on mouse colonic pieces exposed to 2 Minimal Bactericidal Doses--polymyxin B showed no sign of penetration into the colonic mucus, while 2.9% of streptomycin and 60% of the exposed quantity of carbenicillin was detected in the intestinal mucus. Ampicillin, however, has concentrated about three-four times in the intestinal matrix.
    MeSH term(s) Aminoglycosides/pharmacology ; Animals ; Anti-Bacterial Agents/pharmacology ; Culture Media ; Escherichia coli/drug effects ; Escherichia coli/isolation & purification ; In Vitro Techniques ; Intestinal Mucosa/microbiology ; Mice ; Microbial Sensitivity Tests/methods ; Plankton
    Chemical Substances Aminoglycosides ; Anti-Bacterial Agents ; Culture Media
    Language Hungarian
    Publishing date 1993-02-20
    Publishing country Hungary
    Document type English Abstract ; Journal Article
    ZDB-ID 123879-6
    ISSN 1788-6120 ; 0030-6002
    ISSN (online) 1788-6120
    ISSN 0030-6002
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Resistance of Escherichia coli to some antibiotics and biocides in the intestinal biofilm of mice.

    Kétyi, I

    Acta microbiologica Hungarica

    1991  Volume 38, Issue 1, Page(s) 33–41

    Abstract: An artificial monoflora of Escherichia coli in mice, as well as their autochtonous E. coli, exhibited enhanced resistance to streptomycin, chloramphenicol, sodium hypochlorite and silver nitrate. The level of resistance of the monoflora, which was 10-32 ... ...

    Abstract An artificial monoflora of Escherichia coli in mice, as well as their autochtonous E. coli, exhibited enhanced resistance to streptomycin, chloramphenicol, sodium hypochlorite and silver nitrate. The level of resistance of the monoflora, which was 10-32 times higher than the in vitro determined Minimal Bactericidal Dose (MBCD), reached its maximum on the 7th-9th day after implantation. This latency is a requirement for the stabilization of the monoflora. Formaldehyde and carbenicillin were equally effective in the planktonic and in the biofilm mode of growth. In the case of carbenicillin the pieces of mouse colon contained about 60% of the dose used for exposure, in contrast to the 3% rate of streptomycin, showing the excellent penetrating ability of carbenicillin into the intestinal biofilm.
    MeSH term(s) Animals ; Anti-Bacterial Agents/pharmacology ; Carbenicillin/pharmacology ; Chloramphenicol Resistance ; Colon/microbiology ; Colony Count, Microbial ; Drug Resistance, Microbial ; Escherichia coli/drug effects ; Formaldehyde/pharmacology ; Mice ; Microbial Sensitivity Tests ; Penicillin Resistance ; Silver Nitrate/pharmacology ; Sodium Hypochlorite/pharmacology ; Streptomycin/pharmacology
    Chemical Substances Anti-Bacterial Agents ; Formaldehyde (1HG84L3525) ; Silver Nitrate (95IT3W8JZE) ; Sodium Hypochlorite (DY38VHM5OD) ; Carbenicillin (G42ZU72N5G) ; Streptomycin (Y45QSO73OB)
    Language English
    Publishing date 1991
    Publishing country Hungary
    Document type Comparative Study ; Journal Article
    ZDB-ID 605730-5
    ISSN 0231-4622 ; 0001-6187
    ISSN 0231-4622 ; 0001-6187
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Binding of enteric bacteria to hog gastric mucin.

    Kétyi, I

    Acta microbiologica Hungarica

    1990  Volume 37, Issue 1, Page(s) 45–53

    Abstract: The binding features of enteric bacteria were studied using a model mucin of hog gastric origin. The time requirement of binding is short, it is temperature-independent, but dose-dependent. The binding effectiveness of Escherichia coli, Shigella sonnei ... ...

    Abstract The binding features of enteric bacteria were studied using a model mucin of hog gastric origin. The time requirement of binding is short, it is temperature-independent, but dose-dependent. The binding effectiveness of Escherichia coli, Shigella sonnei and Shigella flexneri, as well as Salmonella minnesota had a narrow range: 1.5-9 germs pro pg of mucin. The bacterial ligand of the binding is certainly not a polysaccharide as proved by the uniform binding of the R-mutant series of S. sonnei and S. minnesota. On the basis of inhibition tests by an outer membrane protein fraction, the ligand may be a common outer membrane protein of the enteric bacteria. The outer membrane proteins encoded by the Shigella-EIEC invasivity plasmids do not take part in this binding. The inhibition by killed bacteria or by their culture supernatants of mucin binding of heterologous species may suggest a non-species specific common ligand, too. Similarly to the mucin utilization, the binding ability also seems to be a general phenomenon among the enteric bacteria.
    MeSH term(s) Animals ; Bacterial Outer Membrane Proteins/metabolism ; Enterobacteriaceae/physiology ; Escherichia coli/physiology ; Gastric Mucins/physiology ; Lipopolysaccharides/physiology ; Salmonella/physiology ; Shigella flexneri/physiology ; Shigella sonnei/physiology ; Swine
    Chemical Substances Bacterial Outer Membrane Proteins ; Gastric Mucins ; Lipopolysaccharides
    Language English
    Publishing date 1990
    Publishing country Hungary
    Document type Journal Article
    ZDB-ID 605730-5
    ISSN 0231-4622 ; 0001-6187
    ISSN 0231-4622 ; 0001-6187
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  7. Article: Bakteriális biofilmek és az orvosi gyakorlat.

    Kétyi, I

    Orvosi hetilap

    1989  Volume 130, Issue 46, Page(s) 2455–2457

    Abstract: A suboptimal environment with limited supply of nutrients leads to marked changes in the microbial features. Similar conditions exist also on some tissue surfaces of the human body and on biomedical devices implanted. The basic feature of this ... ...

    Title translation Bacterial biofilms and medical practice.
    Abstract A suboptimal environment with limited supply of nutrients leads to marked changes in the microbial features. Similar conditions exist also on some tissue surfaces of the human body and on biomedical devices implanted. The basic feature of this environmental adaptation is the adherence of microbes to some surfaces and production of abundant exopolysaccharides. Microbes embedded in this hydrated, mostly anionic polysaccharide matrix called biofilm. The biofilm acts not only by trapping the nutrient or oxygen molecules, but protects the microbes against phagocytic cells, antibodies, biocids, and antibiotics, too. This protected form is responsible for the special nature of normal flora, as well as for some clinical and therapeutic characters of several diseases. Microbes liberated from the biofilm, being in the so called planctonic phase. In cases where the biofilms have developed on biomedical devices such planctonic microbes may cause persistent or relapsing infections. These planctonic microbes can be eliminated by the host responses or by antibiotic treatments, while those in the biofilm cannot, thus serving as a source of further infections.
    MeSH term(s) Bacteriological Techniques ; Culture Media ; Polysaccharides
    Chemical Substances Culture Media ; Polysaccharides
    Language Hungarian
    Publishing date 1989-11-12
    Publishing country Hungary
    Document type English Abstract ; Journal Article
    ZDB-ID 123879-6
    ISSN 1788-6120 ; 0030-6002
    ISSN (online) 1788-6120
    ISSN 0030-6002
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  8. Article: Epidemiology of the enteroinvasive Escherichia coli. Observations in Hungary.

    Kétyi, I

    Journal of hygiene, epidemiology, microbiology, and immunology

    1989  Volume 33, Issue 3, Page(s) 261–267

    Abstract: The Hungarian experiences on the epidemiology of enteroinvasive Escherichia coli (EIEC) concerning the dominant serogroup 0124 are summarized. One of the basic differences between Shigella and EIEC infections may be attributed to the higher environmental ...

    Abstract The Hungarian experiences on the epidemiology of enteroinvasive Escherichia coli (EIEC) concerning the dominant serogroup 0124 are summarized. One of the basic differences between Shigella and EIEC infections may be attributed to the higher environmental resistance of EIEC, therefore first of all water-borne outbreaks may be frequent. The other essential difference is in te age incidence: the infection rate of infants is low, the rise of incidence rate begins at the 3rd year and its peak is in the school-children age. EIEC, like to other nosological units of E. coli is not a zoonosis. Symptomless carriership is frequent and may be long lasting with the excretion of the virulent agent for over 1 year.
    MeSH term(s) Adolescent ; Adult ; Carrier State/epidemiology ; Child ; Child, Preschool ; Disease Outbreaks ; Dysentery/microbiology ; Escherichia coli Infections/epidemiology ; Escherichia coli Infections/transmission ; Female ; Humans ; Hungary/epidemiology ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Water Microbiology
    Language English
    Publishing date 1989
    Publishing country Czech Republic
    Document type Journal Article
    ZDB-ID 218216-6
    ISSN 0022-1732
    ISSN 0022-1732
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  9. Article: Biofilm model experiments in vitro with Escherichia coli and Shigella strains.

    Kétyi, I

    Acta microbiologica Hungarica

    1989  Volume 36, Issue 1, Page(s) 41–50

    Abstract: Escherichia coli and Shigella were cultured together in a glucose-free minimal medium completed only by hog gastric mucin. In mixed cultures inoculated simultaneously one member of the pair more or less overgrew the other. This organism remained ... ...

    Abstract Escherichia coli and Shigella were cultured together in a glucose-free minimal medium completed only by hog gastric mucin. In mixed cultures inoculated simultaneously one member of the pair more or less overgrew the other. This organism remained predominant when superinfected with its strain pair after 1, 3, 5 or 7 days incubation. Other signs of the quasi biofilm character of such cultures are the higher level of free polysaccharides and enhanced viscosity in the medium and higher streptomycin resistance of the culture. Around the bacteria a capsule-like material can morphologically be demonstrated.
    MeSH term(s) Biopolymers ; Culture Media/analysis ; Drug Resistance, Microbial/physiology ; Escherichia coli/growth & development ; Escherichia coli/metabolism ; Mucins/metabolism ; Polysaccharides, Bacterial/analysis ; Shigella flexneri/growth & development ; Shigella flexneri/metabolism ; Shigella sonnei/growth & development ; Shigella sonnei/metabolism ; Streptomycin/pharmacology ; Viscosity
    Chemical Substances Biopolymers ; Culture Media ; Mucins ; Polysaccharides, Bacterial ; Streptomycin (Y45QSO73OB)
    Language English
    Publishing date 1989
    Publishing country Hungary
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 605730-5
    ISSN 0231-4622 ; 0001-6187
    ISSN 0231-4622 ; 0001-6187
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Feeding by mucin and intestinal growth of some enteric bacterial pathogens.

    Kétyi, I

    Acta microbiologica Hungarica

    1988  Volume 35, Issue 4, Page(s) 389–395

    Abstract: Enteroinvasive Escherichia coli, Salmonella typhi-murium, Shigella sonnei, Shigella flexneri, as well as E. coli K-12 show dose dependent growth in minimal medium completed with purified hog gastric "Granular Mucin". This ability is based on alpha- ... ...

    Abstract Enteroinvasive Escherichia coli, Salmonella typhi-murium, Shigella sonnei, Shigella flexneri, as well as E. coli K-12 show dose dependent growth in minimal medium completed with purified hog gastric "Granular Mucin". This ability is based on alpha-galactosidase production: defective, melibiose (and galactose) non-fermenting K-12 mutant were unable to utilize mucin. The viability of the parent K-12 strain in the cecal content of mice is significantly higher than that of its Mel- mutant phenotype. In mixed infections of mice the parent strain was the only one to be able to establish a monoflora against its Mel- or Gal- mutants. Among other mechanisms, the growing ability in the intestinal mucous layer may be an additional virulence factor when the enteric pathogens are exposed to a competitive antagonism of the normal flora.
    MeSH term(s) Animals ; Enterobacteriaceae/genetics ; Enterobacteriaceae/growth & development ; Enterobacteriaceae/metabolism ; Enterobacteriaceae/pathogenicity ; Escherichia coli/genetics ; Escherichia coli/growth & development ; Escherichia coli/metabolism ; Escherichia coli/pathogenicity ; Escherichia coli Infections ; Gastric Mucins/metabolism ; Intestinal Diseases/microbiology ; Intestines/microbiology ; Mice ; Shigella/genetics ; Shigella/growth & development ; Shigella/metabolism ; Shigella/pathogenicity ; Species Specificity ; Virulence ; alpha-Galactosidase/genetics ; alpha-Galactosidase/metabolism
    Chemical Substances Gastric Mucins ; alpha-Galactosidase (EC 3.2.1.22)
    Language English
    Publishing date 1988
    Publishing country Hungary
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 605730-5
    ISSN 0231-4622 ; 0001-6187
    ISSN 0231-4622 ; 0001-6187
    Database MEDical Literature Analysis and Retrieval System OnLINE

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