Biomedical subjects

N Hoiby

Publications and source records attributed to N Hoiby.

32 records · Page 2Linked to original sources

PubMed1975

The serology of Pseudomonas aeruginosa analysed by means of quantitative immunoelectrophoretic methods. II. Comparison of the antibody response in man against thirteen O groups of Ps. aeruginosa.

The occurrence of antibodies against antigens prepared from strains representing 13 O groups of Pseudomonas aeruginosa and against a polyvalent Ps. aeruginosa antigen (St-Ag) has been investigated in sera from 100 patients. By means of fused rocket immunoelectrophoresis with intermediate gel it was found that the humoral immune response against Ps. aeruginosa resulting in precipitating antibodies will be detected by St-Ag as well as by any other of the antigen samples investigated. Six of the sera contained group-specific antibodies which were revealed by only one of the antigen samples used and not by St-Ag. These six sera were further studied by means of various quantitative immunoelectrophoretic methods using St-Ag as well as antigens prepared from the infecting Ps. aeruginosa strain in the patient concerned. In all six sera, only one extra precipitin could be detected using antigens prepared from the homologous strain instead of St-Ag. This extra precipitin corresponded presumably to group-specific O-antigens not included in St-Ag. In sera from patients, these group-specific antibodies were always accompanied by antibodies against antigens common to all strains of Ps. aeruginosa.

Antibodies, Bacterial↗

PubMed1975

The serology of Pseudomonas aeruginosa analysed by means of quantitative immunoelectrophoretic methods. III. Reproducibility of a polyvalent P. aeruginosa reference standard-antigen.

The reproducibility of a polyvalent Pseudomonas aeruginosa antigen (St-Ag) composed of a mixture of antigens from 4 O groups of this bacterium has been studied. Ten batches of St-Ag were produced, and each of these and each of the 10 batches of antigens from the 4 strains of P. aeruginosa were compared with St-Ag batch 1 by means of quantitative immunoelectrophoretic methods and a polyvalent antiserum (St-Ab) raised against St-Ag. Fifty-three of the 55 antigens of St-Ag were stable and could be reproduced with reasonable precision in all 10 batches, and 3 of the 4 strains of P. aeruginosa were stable in antigen composition in all batches. One of the strains (0-5A) had lost 2 antigens in the last 5 batches, and the concentrations of 7 other antigens were simultaneously changed, reflecting a smooth-rough dissociation. The disappearance of the 2 antigens in the latest 5 batches of 0-5A was also reflected in similar changes in the antigen composition of the latest 5 batches of St-Ag.

Antigens, Bacterial↗

PubMed1975

Prevalence of mucoid strains of Pseudomonas aeruginosa in bacteriological specimens from patients with cystic fibrosis and patients with other diseases.

The relative prevalence of mucoid strains compared with non-mucoid strains of Pseudomonas aeruginosa has been investigated in all routine bacteriological specimens received in a department of clinical microbiology during 1973. Pseudomonas aeruginosa was isolated from 1054 of the specimens (5.7 per cent) representing 53 patients with cystic fibrosis (551 isolates) and 169 patients with other diseases (503 isolates). The relative prevalence of mucoid strains was significantly higher in specimens from patients with cystic fibrosis (80 per cent) than in specimens from patients with other diseases (3 per cent). Considering patients without cystic fibrosis, the relative prevalence of mucoid strains was low in specimens from all anatomical regions, and no special preference of these strains for the respiratory tract could be demonstrated in these patients, in contrast to the situation in patients with cystic fibrosis. Alternation between mucoid strains and non-mucoid strains in subsequent specimens was observed in 33 of the patients.

Adolescent↗

PubMed1975

Epidemiological markers for Pseudomonas aeruginosa. 6. Relationship between concomitant non-mucoid and mucoid strains from the respiratory tract in cystic fibrosis.

The simultaneously occurring mucoid (M) and non-mucoid (NM) variants of Pseudomonas aeruginosa frequently observed in cultures from the respiratory tract of chronically infected cystic fibrosis patients have been studied. M cultures in vitro were unstable and easily dissociated NM colonies. In a large proportion of the cases, M and NM variants occurring simultaneously in cultures from one and the same clinical specimen were of the same pyocine type, phage type, and serogroup. In some remaining cases there were small differences between the M and NM variants such that identity between the variants from one and the same specimen was possible, although not definite. The NM dissociants from M strains were of the same type as the M variant. The possible role of cross-infection and the interaction of bacteria and host response factors continuously tending to select the unstable M variant in vivo are discussed.

Adolescent↗

PubMed1974