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W Witte

Publications and source records attributed to W Witte.

At least 55 records · Page 3Linked to original sources
PubMed1982

Multiple drug-resistant Staphylococcus aureus with resistance to oxytetracycline and minocycline, an example for the distribution of a multiresistant strain-clone.

Multiresistant S. aureus-strains with chromosomally localized determinant for resistance to oxytetracycline-minocycline (tmn) exhibit uniform characteristics, obviously they have been spread as a clone. These strains harbour two plasmids: one with MW of 18 MD for beta-lactamase and determinants for resistance to mercury and to cadmium and one with MW of 2 MD for resistance to chloramphenicol. Beside the tmn-determinant, also the determinants for resistance to macrolides and to gentamicin are not located on plasmids. The tmn-determinant is specific for defined hospital strains reacting with group-III phages; it was not found in other strains of different origin.

Anti-Bacterial Agents↗
PubMed1981

[Role of phage in the transfer of plasmids in mixed cultures of Staphylococcus aureus (author's transl)].

Lysogenicity with phages of serogroup B is a prerequisite to the transfer of drug resistance plasmids in mixed cultures of Staphylococcus aureus. This is demonstrated by experiments with transfer of the plasmids pII 147, pC 221, pT 127, pE 2222 to strain 8325-4 which was lysogenized for different phages of different serogroups (Table 2). The transfer is also possible, when the donor strain or the recipient strain are lysogenic for the phage mutant phi 11, M 28, which is able to lyse strain 8325-4 but unable to form phage heads (Kretschmer and Egan, 1975). The fact that the induction of prophage phi 11 and steps of phage-propagation are necessary for the transfer, is evident from negative results obtained by use of the rec--mutant of strain 8325 (RN 981) as donor and by use of strain 8325-4 lysogenic for the phage mutant phi 11, A 4 as donor. The phage mutant phi 11, A 4 is defective at an early step of phage propagation. These experiments are shown in Tables 3 and 4. The possibility of transfer using donor or recipient strains which are lysogenic for a phage-mutant but unable to form phage heads clearly shows that the transfer is not based on transduction. Incubation of non lysogenic donor and recipient cells in the culture supernatant of strain 8325-4 (phi 11, M 28) or in the lysate of strain 8325-4 obtained after infection with phage phi 11, M 28 also allows the transfer of plasmids. Obviously one of the components of serogroup B phages is essential for the transfer.

Lysogeny↗
PubMed1980

[Staphylococcus aureus infection in chickens in industrialized poultry units. 2. Microbiological studies: Staphylococcus aureus and other pathogens].

Checks were applied to 3,213 dead or ill broiler chickens and broiler parents for the purpose of elucidating enzootic or epizootic Staphylococcus aureus infections which had occurred on three industrialised poultry units. Rates of Staphylococcus aureus detection and identification declined by the following order: staphylococcal septicaemia (100 per cent), dermatitis (75.42 per cent), arthritis and tenosynovitis or osteomyelitis (64.59 per cent), wound infections (24.02 per cent), infection of bursa suprasternalis (18.94 per cent), underdevelopment (8.70 per cent), navel-yolksac-peritonitis (7.83 per cent), and conjunctivitis (7.14 per cent). Staphylococcus aureus was found to be the most important pathogen of arthritis with synovitis and of osteomyelitis with epiphysiolysis, the rate of detection being directly correlated with the severity of the pathologico-anatomic alterations established. Attempts to culture mycoplasmas from irritated synovial sheaths were successful only in three of 56 examined animals (5.3 per cent). The site variety of gallinae or strains of the crystal-violet Type A with lysis patterns of 84, 53, 77 and 84 accounted for 78.1 per cent of all Staphylococcus aureus strains isolated from infected fowl. Their percentual importance was 85.0 for septicaemia, dermatitis, and arthritis with synovitis and osteomyelitis. For prophylaxis and control of Staphylococcus aureus infections of fowl on elimination of predisposing factors and on the control of epidemic occurrence of the above types.

Animals↗
PubMed1980

[Staphylococcus aureus infection in chickens in industrialized poultry units. 3. Experimental infection of chickens and comparison of pathogenicity of Staphylococcus aureus of different origin].

Day-old chicks were subcutaneously infected with Staphylococcus aureus strains of site variety gallinae and crystalviolet Type A. The lysis patterns involved were with phages 84 as well as with phages 53, 77, and 84 of the international base scheme for human staphylococci. In fowl with synovitis and arthritis, osteomyelitis, dermatitis, and septicaemia, 52 of 57 tested strains (91.2 per cent) produced on the site of injection pathognomic oedematous-haemorrhagic and necrotising changes of the skin and hypodermis (haemorrhagic dermatitis) in a way which is characteristic also of natural diseases. However, no specific skin changes could be produced by subcutaneous infection of nine strains of site variety hominis or undefinable category with differentiated biochemical properties and lysis patterns. They had been isolated from cases of compound infection, salpingitis and wound infections as well as from one case of arthritis. Fifty-seven strains, obtained from mammals, were tested subcutaneously, on day-old chicks, among them 21 strains of site varieties of bovis, canis, ovis, and hominis. However, only four of those strains, isolated from miscarried pig foetuses and cattle with mastitis, caused, oedematisation and exudation (7.02 per cent), but no haemorrhagia and only minor lysis and necrosis of skin. The minimum dose required to induce haemolytic dermatitis was 11 x 10(3) pathogens, and the lowest lethal dose of six tested strains was between 11 x 10(5) and 26 x 10(7) pathogens. The lowest dose of mammalian strains with lethality to day-old chicks was [10 bis]10(4) times as high as the lowest dose of fowl strains. Subcutaneous infection of day-old chicks has worked well as a high-speed test by which to differentiate between fowl-pathogenic Staphylococcus aureus strains, on the one hand, and mammalian strains, on the other. The need for delimitation of such strains has been confirmed by the above experimental infections. Against the background of the above results, guidelines are proposed for the control of Staphylococcus aureus infection of fowl.

Animals↗
PubMed1979

[Phage typing and lysogen typing of Staphylococcus aureus].

A comparison was made between the results of phage and lysogenic typing of S. aureus strains isolated during several outbreaks of staphylococcal infection and S. aureus cultures isolated from the same carriers at different periods. The study of the groups of strains having the same origin showed that the differences in the number of reactions were more pronounced in lysogenic typing than in phage typing. For this reason lysogenic typing can be recommended only for the identification of those strains which cannot be identified with the use of the phages of the International Basic Set. The results of the experiments with induced phages proliferating in a restriction-defective strain indicated that restriction and modification were mainly responsible for the specificity of lytic reactions.

Animals↗
PubMed1979

[Staphylococcus aureus infections in domestic fowls. 1. Ecology and epizootiology. (Review)].

The ecological and epizootiological aspects relating to Staphylococcus aureus in domestic fowl are expounded, on the basis of literature, with particular reference being made to five topics: occurrence of these conditionally pathogenic bacteria in domestic fowl, point of attack and routes of infection, conditions for possible occurrence of infections, reciprocal infection between man and animal, as well as aspects of therapy and prophylaxis.

Animals↗
PubMed1978

[The mutual transmission of Staphylococcus aureus between humans and cattle and the environmental adaptation of hemolysin and fibrinolysin formation].

In an ecological investigation in 20 dairy herds of cattle we compared the characteristics of strains isolated from nasal swabs of milkers, from the udder of cows and from cases of mastitis in cows. In 7 herds we found definite strains in the nasal flora of the milkers and in the udder-flora of the cows which only differ in the formation of hemolysin and of fibrinolysin. In the other checked characteristics strains from man and strains from cattle show identical patterns. In 5 herds these strains correspond to the host-specific variety hominis, in 2 herds to the hostspecific--variety bovis. These results refer to an environmental adaptation of the phenotypically detectable formation of hemolysins and fibrinolysin. From the ecological point of view an exchange of strains between man and cattle is likely. The origin of strains which can not be alloted to one ot the known host-specific varieties can be explained by an environmental adaptation. Besides the facts that strains of the host-specific variety bovis occur only very rarely in man and that strains of the host-specific variety hominis occur occasionally in cattle the clinical significance of the reported results has to be clarified by further investigations.

Adaptation, Biological↗
PubMed1978

[Macrolid resistance in Staphylococcus aureus strains from chicken synovitis and dermatitis in industrial production].

In outbreaks of synovitis and dermatitis in chicken caused by Staphylococcus (Staph.) aureus we observed erythromycin-resistant strains. These strains belong to the host-specific variety gallinae of Staph. aureus or can not be alloted to one of the known host-specific varieties. The macrolide-resistance-determinant is not carried by a plasmid, presumably it is located on the chromosome. The strains show constitutively cross-resistance to erythromycin, thurimycin, linomycinc and pristinamycin (M-L-S-phenotype). An ecological investigation in a chicken farm has shown that there is no distribution of Staph. aureus-strains from chicken to workers and no occurence of macrolide-resistance in Staph. aureus-strains from the workers.

Animals↗
PubMed1978

Ecology of Staphylococcus aureus: comparative characterization of strains isolated from man, cattle and sheep in Bulgaria and in the GDR.

Staphylococcus aureus strains from man, cattle and sheep have been differentiated by biochemical tests and by phage typing. Strains from pathological material of human origin mostly belong to the host-specific variety hominis, strains from mastitis in cattle mostly belong to the host-specific variety bovis. However, there are also strains from cattle which cannot be allotted to one of the known host-specific varieties and also strains which belong to the host-specific variety hominis. Strains from mastitis in sheep clearly differ from strains of human and bovine origin; these strains are designated as variety ovis. The frequency distribution of the host-specific varieties in man, cattle and sheep is the same in Bulgaria and in the GDR.

Animals↗
PubMed1978

[Characteristics of Staphylococcus aureus strains from pathological processes in swine].

120 Staphylococcus aureus strains from different and sporadic pathological process in swines have been investigated on biochemical properties and phage patterns. 98 strains (82%) exhibit coagulation of human plasma, no coagulation of bovine plasma, crystal-violet-type C, hemolysin-type beta, no formation of fibrinolysine and sensitivity for phages of group I, III and M. Only in few strains we observed reactions with phages of group II. 26 from 66 strains were resistant to antibiotics, and among them 24 showed resistance to oxytetracacline.

Animals↗
PubMed1978

[Transfer of drug resistance plasmids from Staphylococcus epidermidis to Staphylococcus aureus in mixed culture].

A possibility of transfer of chloramphenicol-resistance and penicillin-resistance plasmids from 4 different donor S. epidermidis strains to 2 S. aureus strains was demonstrated. Chloramphenocol-resistance plasmid was found in S. epidermidis 1065/77 which was not expressed in this strain but could be transferred to and was expressed in Staphylococcus aureus strains. Penicillin-resistance and chloramphenicol-resistance plasmids were transferred simultaneously in 40 per cent of the colonies.

Chloramphenicol↗
PubMed1978

[Chemical and immunogenic properties of the capsular antigen of Staphylococcus aureus. III. Protective activity of capsular antigen in experiments on mice].

Experiments were conducted on 1500 albino mice; protective activity of 7 batches of S. aureus capsular antigen isolated from 5 strains was studied. The animals were immunized subcutaneously with different doses of the preparation (from 0.001 to 10000 microgram) once, twice, and thrice, and infected intraperitoneally with 6 encapsulated cultures. Capsular antigen proved to possess weak protective properties. The following regularities were revealed: 1) high antigen doses (over 5 microgram) increased mouse sensitivity to staphylococcus infection; 2) the greatest protective activity was shown by doses within 0.01-1 microgram; 3) there was no distinct "dose-effect" dependence; 4) single immunization was less effective than double and triple; 5) antigenic specificity of the capsular material was not connected with its protective properties.

Animals↗