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H Brandis

Publications and source records attributed to H Brandis.

At least 55 records · Page 3Linked to original sources
PubMed1979

Studies on a receptor for pyocin in a R mutant of Salmonella minnesota.

Lipopolysaccharide (LPS) isolated from the pyocin sensitive R form strain of Salmonella minnesota F6 (chemotype Rd1) inhibited the activity of bacteriophage tail-like pyocin P1 whereas no inhibition occurred with LPS prepared from the pyocin resistant S form of S. minnesota. Subunits of lipopolysaccharide obtained by treatment with sodium deoxycholate and the polysaccharide fraction of the lipopolysaccharide obtained by acid hydrolysis were shown to be still active whereas lipid A fraction had no pyocin neutralizing activity. The (KDO)3-hepI-hepII unit, which terminates the lipopolysaccharide of S. minnesota F6 was, therefore, suggested to determine the specificity of the pyocin P1 receptor.

Bacteriocins↗
PubMed1979

Maintenance of Fc receptors in hybrid cell lines obtained by fusing mouse splenic macrophages with mouse myeloma cells.

Mouse splenic macrophages were fused with cells of the mouse myeloma line P3-X63-Ag8 in the presence of inactivated Sendai virus. Two continuously growing hybrid cell lines were established from fusion mixtures. These hybrid cell lines exhibited macrophage-like morphology and continued to express macrophage derived Fc receptor activity even after prolonged culture in vitro.

Animals↗
PubMed1979

[A fi- tetracyclin resistance plasmid with specific restriction of phages on salmonella typhi, S. paratyphi B and S. typhi-murium (author's transl)].

Among 262 strains of Salmonella typhi from an epidemic outbreak of typhoid fever in Baden-Württemberg in 1974 2 strains were isolated which were tetracyclin resistant and showed no reactions with the Vi testphages T, D6 and VII whilst all other strains belonged to lysotype A, subtype Tananarive. It turned out that the Tc resistance in both strains was caused by a fi- R plasmid which could be transfered to other S. typhi strains, to E. coli K12, S. paratyphi B, S. java and S. typhi-murium as well as from Tc resistant E. coli K12 back to S. typhi. The Tc R plasmid introduced in S. typhi, lysotype A, caused specific restrictions of typing phages T, D6 and VII. Also, the transfer of the plasmids to strains of S. paratyphi B and S. typhi-murium resulted in restrictions of a number of typing phages. Both plasmids had identical patterns of restriction. In this pattern the Tc R plasmid differed from those described in the literature.

Drug Resistance, Microbial↗
PubMed1978

[Relationship between MIC and Zone Size (author's transl)].

The one antibiotic-one disk agar diffusion test for susceptibility testing of clinical isolates, though technically similar to that used for determining antibiotic concentrations in body fluids, lacks the exactness of the latter. In correlating zone diameters to MICs, stochastic linearity should be evaluated besides the regression lines and the correlation coefficient.

Anti-Bacterial Agents↗
PubMed1978

Characterization of plasmids in bacteriocin producing strains of Streptococcus faecium.

Four bacteriocin (enterocin) producing strains of Streptococcus faecium were examined for extrachromosomal DNA. Three strains proved to harbor minicircular plasmid DNA of uniform length as evidenced by CsCl ethidium bromide density centrifugation and electron microscopy. Molecular weight determination obtained through contour length measurements showed 2.4 X 10(6) dalton for S. faecium 25, 3.4 X 10(6) dalton for S. faecium 3 and 3.8 X 10(6) dalton for S. faecium 59. Elimination experiments for bacteriocin production with intercalating dyes proved sterile. The role of these plasmids remains for the time being unknown.

Anti-Bacterial Agents↗
PubMed1978

Preliminary results of phage typing of coagulase-negative staphylococci with the set of typing phages of Pulverer and co-workers.

120 strains of Staphylococcus epidermidis isolated from clinical material were typed with the set of 16 test phages described by Pulverer et al. (1975). 58 (48%) strains were typable with RTD and additionally 12 strains with 100 times RTD. The pattern Ph10/U14/U16 was observed most common (36 strains), followed by the pattern U14/U16 (11 strains). One strain showed lysis reactions with all typing phages. With 61 strains phage U14 gave a lysis whereas phage U20 reacted only with 4 strains. The S. epidermidis phages were not specific for this species, at least some of these showed lysis reactions with S. aureus strains. The lysis pattern most often observed was Ph10/U14/U16. There was no correlation between the patterns given by the S. aureus test phages and those by the S. epidermidis phages.

Bacteriophage Typing↗
PubMed1978

[Epidemiological investigation of staphylococcal infections in stocks of SPF-animall (author's transl)].

The occurrence and spread of staphylococcal infections in stocks of SPF-animals were studied over a period of more than three years. The results were compared with observations made by other authors. Staphylococcus aureus strains isolated from both sick and healthy animals (mice, rats, rabbits, guinea pigs) as well as from veterinary staff were lysotyped with the international phage set for epidemiological investigations. The majority of the lysotypes demonstrated in sick mice and rats belonged to lysogroup III (77% and 96% respectively). S. aureus strains with the phage patterns III 6/42E/47/53/54/75/83A/ +, III 54/83A and III 54/83A/85 were most common amongst these animals. The lysotype 80/3c/47/53/54/75/84/85 + occurred in rabbits and guinea pigs only. S. aureus strains of lysogroup I and II, which are frequently involved in skin infections of man, were either found only very scarcely or not at all discovered in the animals tested. Among the veterinary personnel staphylococcal strains of the lysogroups I and III as well as non-classificable strains occurred at a similar rate of approximately 25% each. Several lysotypes (I 29, III 42E/47/53/54/75/77/84/ + M 187) persisted in members of the staff over a stretch of two to three years without causing infection to the animals under their charge. On the other hand, lysotypes isolated from infection sites (abscesses) in the animals were mostly found also in swabs from the nasopharynx of healthy animals and the personnel. The implications of the importation and the spreading of Staphylococci in animal stocks by veterinary staff are pointed out. Factors promoting staphylococcal diseases in animals and measures to prevent S. aureus infection from SPF-animal stocks are discussed.

Animals↗
PubMed1977

Specifically immune mouse T-cells can destroy H-2 compatible murine target cells infected with herpes simplex virus types 1 or 2.

Lymphocytes from the spleen (SL) or peritoneal cavities (PL) of HSV-1- or HSV-2-immunized C 3 H mice expressed pronounced cytotoxicity, as measured by 51Cr release assay, against L cells experimentally infected with HSF-types 1 or 2 but not against uninfected L cells. HSV-1 or HSV-2 immune lymphocytes induced substantially more 51Cr release when L-cell targets were infected with homotypic virus compared to those infected with heterotypic virus. Inasmuch as the cytotoxicity of specifically immune C 3 H SL for HSV-infected L cells was selectively eliminated by treatment with AKR anti-theta C 3 H serum plus complement, the effector cells in present system were theta-bearing T cells. Evidence has been provided which indicates that specifically immune T cells express cytotoxicity exclusively directed against different HSV-infected target cells (mouse embryo cells or mouse peritoneal macrophages) which share H-2 antigens with the effector cells.

Animals↗
PubMed1977

[Results of phage typing of Salmonella typhi and Salmonella paratyphi-B in the years 1970-1973 (author's transl)].

Between 1.1.1970 and 31.12.1973 3639 strains were typed with the aid of phage typing. Of these strains 1793 belonged to S. typhi and 1846 to S. parathyphi-B. 40 S. typhi phage types were found. 9 of these occurred in a frequency of more than 1% (relevant to foci). These were E1 (25.7%) (of this E1a 19.7%, E1b 5.9%), A (16.6%), F1 (7.5%), D1 (59%), C1 (5.4%) D2 (2.3%), 46 (2.1%), 28 (1.9%). Among S. paratyphi-B 24 phage types resp. varieties were found, 14 of these occurred in a frequency of more than 1% (relevant to foci). The phage types comprised Taunton (36.8%), 1 m.c. (10.3%), 3aI m.c. (7.5%), B.A.O.R. (6.8%), 3 a m.c. (4.9%), Dundee (4.6%), 3 aI var. 1 (4.6%), Beccles m.c. (2.4%), 3 b m.c. (2.3%), 3 aI var. (2%), 1 var. (1.8%), 3 aI var. 4 (1.1%). As far as it came to be known the epidemiological relations and particularities of the different S. typhi and S. paratyphi-B phage types are discussed. In th period of this report only one larger epidemic outbreak of S. paratyphi-B (type Taunton) occurred. Possibly the cause of this was contaminated milk.

Bacteriophage Typing↗
PubMed1977

[Electronenmicroscopic Studies on Cells of Listeria monocytogenes Treated with Enterocin (author's transl)].

Purified enterocin E1A, a bacteriocin produced by Streptococcus faecium E1, had a strong bactericidal activity on susceptible cells of Listeria monocytogenes. Electronmicroscopic observation of thin sections of L. monocytogenes, treated with enterocin E1A at a concentration that gave 0.1% survivors, revealed that the predominant features of morphological alterations concern the partial dissolution of the cell content and the damage of the cell envelope which enabled an efflux of cell-material. Not frequently intact protoplasts and greatly elongated cells were observed.

Bacteriocins↗
PubMed1977

Search for the presence of lectin-binding sites on Toxoplasma gondii.

Evidence for the presence of carbohydrate on the surface membrane of Toxoplasma gondii trophozoites and on the cell wall of toxoplasma brain cysts was sought by fluorescent lectin staining. Using FITC-conjugated preparations of Concanavalin A (Con A), wheat germ agglutinin (WGA), or soy bean agglutinin (SBA), we have failed to obtain evidence for the binding of these lectins on the surface of T. gondii trophozoites. In contrast, the three test lectins bound effectively and specifically to the wall of toxoplasma brain cysts. Prefixation of cysts with glutaraldehyde or brief trypsinization of cysts did not affect the intensity of cyst wall fluorescence when stained with FITC-conjugated Con A, SBA, or WGA. The results are interpreted to indicate that whereas exposed Con A, SBA, and WGA binding sites are associated with the wall of toxoplasma brain cysts, such lectin-binding saccharide residues are not present on the surface of trophozoites in exposed or reactive form.

Animals↗
PubMed1976

Appearance of IgG (Fc) receptor(s) on cultured human fibroblasts infected with human cytomegalovirus.

Cultured human diploid fibroblasts (WI-38) after infection with human cytomegalovirus (CMV) but not when uninfected, could hemadsorb sheep red blood cells (SRBC) coated with rabbit anti-SRBC IgG. The adsorption of IgG-coated SRBC to virus-infected cells was completely abolished if the tests were carried out in the simultaneous presence of rabbit antiserum elicited against CMV. Normal sera of rabbit or human origin as well as purified human IgG but not Fab fragment of human IgG could also abolish the binding of sensitized SRBC to CMV-infected fibroblasts. Active metabolism on the part of CMV-infected fibroblasts proved to be an important requisite for demonstrating binding of sensitized SRBC to their surfaces. By using an indicator Staphylococcus aureus to which rabbit antiserum against normal human IgG, IgM, or IgA was bound via Fc fragments, evidence has been obtained which suggests the existence of receptor(s) on CMV-infected WI-38 cells that react specifically with Fc region of human IgG.

Animals↗
PubMed1975

[Nature of bacteriocins].

The bacteriocins comprise a large, heterogeneous group of bactericidal substances produced by bacteria from widely differing species. The best known bacteriocins are the colicins. Some aspects of research on colicins are discussed especially their chemical nature and mode of action, and their genetic determinants.

Bacteriocins↗
PubMed1975

Effects of enterocin E1A on the ultrastructure of Streptococcus faecium.

Streptococcus faecium 158 cells were examined by electron microscopy at sequential intervals after addition of enterocin E1A, a bacteriocin produced by Streptococcus faecium E1. After addition of enterocin E1A, the nuclear material began to concentrate into distinct areas at the center of the bacteria. In a later stage, extensive condensation of the nuclear filaments left a small cluster of dense granules within a cytoplasmic vacuole, and 10-20% of the cells underwent a complete lysis.

Enterobactin↗