PubMed Health⌕ Search

Biomedical subjects

R Ansorg

Publications and source records attributed to R Ansorg.

At least 73 records · Page 4Linked to original sources
PubMed1981

[Bacterial endocarditis in congenital heart defects (author's transl)].

Seven patients with bacterial endocarditis have been treated at the Department of Pediatric Cardiology University Göttingen from September 1975 to July 1978. All of them had congenital heart defects considered as a predisposing condition and confirmed by previous cardiac catheterization, three patients were cyanotic. Unlike the spectrum of micro-organisms prevalent hitherto Pseudomonas aeruginosa was isolated in three cases. In one of these patients antibiotic drug therapy was unsuccessful and only surgical management with closure of the rest-VSD and excision of the endocardiac lesions was finally helpful. Another patient died and Pseudomonas aeruginosa endocarditis was disclosed by post mortem examination only. The onset of symptoms in four patients was less than six months after cardiac surgery. In two cases aortic valve prosthesis became necessary. No relapse during the further follow up period was observed.

Adolescent↗
PubMed1981

[Prevention of postoperative Candida endomycoses. Candida colonization and Candida antibodies in patients undergoing cardiovascular surgery].

Of 23 patients undergoing heart surgery and 11 patients undergoing vessel surgery 26 (76%) are colonized with Candida albicans on admission to hospital. Postoperatively the yeast quantity in the mucocutaneous flora remains nearly constant in both groups. However, during the 2nd-3rd week after operation 21 heart surgery patients and 3 vessel surgery patients developed a significant rise in Candida antibodies in the Ig-classes G, M and/or A. Eight weeks after surgery the IgM-antibodies once again reached preoperative values in 14 of 16 patients; the IgG- and IgA-antibodies, however, tend to be of longer persistent. The antibody response is most probably due to Candida invasion via tracheal traumatization by prolonged intubation. Persistent elevation of IgM-antibodies indicates preventive antifungal therapy.

Adult↗
PubMed1980

[Immunological and electrophoretic characterization of flagellins of different H-types of Pseudomonas aeruginosa (author's transl)].

P. aeruginosa flagella of the complex serotype a (a0, a2, a3) and the uniform serotype b were isolated, purified, and depolymerized by heat. The flagellins obtained form one precipitin band each and show reactions of non-identity in Ouchterlony tests. The immunologic reaction is not altered by treatment with SDS and mercaptoethanol. In disc microelectrophoresis and SDS gradient gel microelectrophoresis on polyacrylamide gels, the flagellins migrate as homogeneous proteins. They have identical electrophoretic mobilities and a molecular weight of about 50,000.

Antigens, Bacterial↗
PubMed1980

[O-antigen determination and identification of Pseudomonas aeruginosa (author's transl)].

The quality of the morphological-biochemical identification of P. aeruginosa affects the results of group determination with anti-O-sera (Institute Pasteur Production) to a great extent. Out of 563 isolates classified as P. aeruginosa on the basis of colony morphology, haemolysis, pigment formation, odor, gramstaining and oxidase test, 84,2% react with one monovalent antiserum. Out of 498 strains which are more exactly identified by additional use of the Oxi/Ferm tube-system (Hoffmann-La Roche), 94,0% are clearly to be grouped. The O-antigen determination is not appropriate for inter-species differentiation of P. aeruginosa, due to common antigens with P. aeruginosa related species.

Agglutination Tests↗
PubMed1980

[Isolation, depolymerization and repolymerization of flagella of Pseudomonas aeruginosa (author's transl)].

Flagellar filaments of P. aeruginosa are isolated and purified by cultivating the cells in fluid medium, followed by shaking in a rotation-homogenizer and by fractional centrifugation. The electronmicroscopically pure preparations are partially disintegrated by heating at 60-100 degrees C/30 min. The flagellin repolymerizes spontaneously into flagella-like but straight filaments. In the indirect fluorescent antibody test, isolated flagellar filaments and polymerized flagellin-filaments with antiflagellar antibodies like flagella of native cells.

Culture Media↗
PubMed1979

[Studies on tissue affinity of serogroups of Pseudomonas aeruginosa (author's transl)].

The distributions of serogroups of 316 Pseudomonas aeruginosa strains isolated from respiratory secretions (134), urines (105) and wound secretions (77) of patients in various hospitals show significant accumulations of 0-groups 1 (wound secretions), 4 and 5 (respiratory secretions). The statistical prevalence of these serogroups is due to their overproportional frequency in specimens from particular hospitals and, therefore, caused by local epidemiologic situations. There is no evidence that P. aeruginosa strains with certain 0 antigens have a special affinity to wounds, the respiratory, or the urinary tract.

Humans↗
PubMed1978

[Antibody response to somatic and flagellar antigens of Pseudomonas aeruginosa (author's transl)].

Using the indirect fluorescent antibody technique, the production of antiflagellar and antisomatic antibodies in rabbits immunized with different P. aeruginosa strains is measured. After 6 injections of formalinized cultures in graded doses over 3 weeks, the antiflagellar antibodies reach the peak in the 4th to 5th week, followed by a rapid fall. The antisomatic antibodies reacting with native and boiled cells show a plateau-shaped maximum from the 3rd to 5th/6th week and fell slightly up to the 11th week. A significant dissociation of antiflagellar and antisomatic antibodies, however, is not observed. The antisomatic antibodies are less absorbed by protein A (Staph. aureus) than are the antiflagellar antibodies.

Absorption↗
PubMed1978

[In vitro effect of fosfomycin against Pseudomonas aeruginosa compared to carbenicillin, gentamycin and polymyxin B].

The activity of fosfomycin against Pseudomonas aeruginosa (78 serotyped strains isolated from clinical specimens) is considerably more dependent on test conditions than that of carbenicillin, polymyxin B or gentamicin. Using a degree of standardization of the micro-serial dilution test and agar diffusion test (Iso-Sensitest broth and agar), which yields a high degree of correlation between the values of both techniques with carbenicillin and gentamicin, a moderate degree of correlation is obtained with fosfomycin. In regard to minimal inhibitory concentration (MIC) values in human serum and human urine, fewer "false" results are obtained in Iso-Sensitest broth than in Mueller Hinton broth and in particular glucose caseinhydrolysate broth. On the basis of MIC values in Iso-Sensitest broth P. aeruginosa is much more sensitive to polymyxin B, carbenicillin and gentamicin than to fosfomycin.

Anti-Bacterial Agents↗
PubMed1978

[Flagella specific H antigenic schema of Pseudomonas aeruginosa (author's transl)].

Serogrouping of P. aeruginosa on the basis of heat-stable somatic (O-)agglutinogens is well established, but H-typing on the basis of heat-labile agglutinogens is not accepted generally because of uncertain flagella specificity. In contrast to the agglutination reaction, the indirect fluorescent antibody technique allows the differentiation of soma and flagellum of P. aeruginosa cells at the morphological and serological level simultaneously, and thereby the specific analysis of flagellar (H-)antigens, even with OH-antisera. Using this technique the complex flagella-antigen a with the partial antigens a0, a1, a2, a3, a4 and the uniform flagella-antigen b are differentiated by cross absorption experiments. As the partial factors a1-a4 are independent determinants, a flagellar antigenic schema containing 17 H-types is devised. Type strains, immunization and absorption procedures for preparing diagnostic antisera are described. O-group and H-type show free combination. Completing the extended O antigenic schema of Habs (slide agglutination) with the flagella specific H antigenic schema (indirect fluorescent antibody technique), a detailed OH typing system of P. aeruginosa is obtained, by which clinical isolates are subdivided into 99 serovars.

Antigens, Bacterial↗
PubMed1978

[Antibody induced phase variation in Pseudomonas aeruginosa (author's transl)].

To extend the flagella specific H antigenic schema of P. aeruginosa (ANSORG, 1978), investigations are carried out to reveal phase variation in this species as in Salmonella or Arizona. With conventional methods, i.e. examination of single colonies after plating the cultures on standard nutrient agar or the phase reversal techniques of Craigie (1931) and Gard (1938) by adding homologous anti-OH-serum of different amounts in semisolid agar medium, no change of the flagellar antigens of various P. aeruginosa strains is observed using the indirect fluorescent antibody technique. When subcultivated in pure homologous anti-OH-serum, however, the cells express stepwise a second H phase, which is different from the original flagellar antigens. In control experiments with serum from non-immunized rabbits the original flagellar antigens remain constant. The phase variation affects only the H antigen, is reversible by cultivation on soft agar medium and is characterized by the nonspecific type-overlapping antigen u. After absorption of immunserum prepared with cells cultivated in homologous anti-OH-serum by cells cultivated on soft agar medium, an antiserum specific for factor u is obtained. Since fresh isolates do not react with anti-u-serum, the diphasic nature of P. aeruginosa is probably of minor significance for H typing in practice.

Antigens, Bacterial↗
PubMed1978

[Studies on the antimicrobial effect of natural and synthetic humic acids (author's transl)].

Preparations of humic acids extracted from different soils by various methods and model humus substances obtained synthetically by oxidation of hydroquinone and pyrocatechin are tested for growth inhibition of representative strains of human pathogenic microorganisms using a micro serial dilution technique. Within the concentration range of less than or equal to 2500 micrograms/ml 57 of 81 natural and also the two synthetic humic acids show antimicrobial activity with differing spectra. These substances inhibit St. epidermidis, St. aureus, Str. pyogenes, S. typhimurium, Prot. vulgaris, Ent. cloacae, Ps. aeruginosa and C. albicans, but not Str. faecalis and E. coli. The degree of activity or the sensitivity of test organisms, respectively, amounts to 2500--1250 micrograms/ml predominantly, partially 625--312 micrograms/ml and can reach values of up to 39 micrograms/ml with synthetic hydroquinone humic acid. The spectrum and degree of activity vary according to the origin and extraction mode of the natural humic acids. The in vitro evidence of efficiacy against human pathogenic microorganisms gives a rational basis of therapeutic use of substances of humic acid type in infectious conditions.

Anti-Bacterial Agents↗
PubMed1978

[Permanence and parellelism of serogroups of Pseudomonas aeruginosa in hospitalized patients (author's transl)].

The determination of O-antigens of 248 serial isolates of Ps. aeruginosa from 50 patients with respiratory, urinary tract or wound infections reveals that over a period of 41 (8-178) days in 12% of cases a change, in 88% no variation of serogroup at the infection site occurs. Simultaneous incidence of different serogroups in the same specimen is not observed. 55 parallel isolates from the various lesions of 26 multiinfected patients have in 46% of cases different serogroups, in 54% the same serogroup. The striking permanence of serogroups at a particular infection site indicates that the O-antigens of Ps. aeruginosa remain constant under natural infection conditions. A change in serogroup suggests--considering the frequent parallelism of different serogroups--reinfection by a new strain.

Antigens, Bacterial↗
PubMed1977

Drug elimination by hemofiltration.

Elimination by hemofiltration of gentamicin, doxycylin, ampicillin, sulfamethoxazole and clofibrate was measured in patients with chronic renal insufficiency. Clearance values of ampicillin and clofibrate were roughly in the range that might be expected according to the reported protein binding values of these drugs, whereas doxycyclin and sulfamethoxazole were eliminated to a much higher degree. Gentamicin clearances during a 6-hour hemofiltration treatment were lower than should be expected from reported protein binding values. For gentamicin and doxycyclin the filtered fraction linearly increased with time, a phenomenon which may be explained by membrane polarization.

Ampicillin↗