Search PubMed⌕ Search

Biomedical subjects

H Rollag

Publications and source records attributed to H Rollag.

At least 91 records · Page 5Linked to original sources
PubMed1981

Effect of interferon preparations on the uptake of non-opsonized Escherichia coli by mouse peritoneal macrophages.

Uptake of non-opsonized Escherichia coli by mouse peritoneal macrophages (MPM) is influenced by pre-treatment of MPM with homologous interferon preparations. Incubation of MPM with 10(2)-10(3) units of interferon per ml for 18 hours resulted in a 30-70 per cent increase in the phagocytosis rate as well as maximal phagocytic capacity. This effect was time dependent. At least seven hours of interferon pre-treatment and a phagocytosis period of 90 minutes were necessary for a statistically significant increase of the phagocytosis. Treatment of MPM with high concentrations of interferon (i.e. more than 10(4) units per ml) had a depressive effect on the phagocytosis. Both the enhancing and the depressive effects were characterized by the standard physico-chemical properties of interferons. Both effects were species specific. The phagocytosis enhancing effect was neutralized by anit-interferon serum.

Animals↗
PubMed1980

Degradation of non-opsonized 32P-labelled E. coli by unstimulated mouse peritoneal macrophages. Evaluation of a method.

Five hours after the ingestion of non-opsonized E. coli by mouse peritoneal macrophages in vitro, 60-70 per cent of the bacteria were killed, estimated as decrease in colony forming units. When employing 32P-labelled E. coli, 50-60 per cent of the radioactivity was released to the medium by the macrophages during the same period of time. The mean number of visually-counted bacteria per macrophage was constant in the post-ingestive period. The macrophages killed the bacteria without early destruction. The release of radioactivity seemed to reflect the degradation of bacteria in the macrophages.

Animals↗
PubMed1980

Pathogenesis of Sendasi virus infection in mice. On the possible role of interferon on the development of disease.

Intraperitoneally (i.p.) injected interferon prolonged the survival time of mice inoculated intranasally (i.n.) with Sendai virus and reduced the mortality in mice inoculated i.n. with Haemophilus influenzae. Moderate concentrations of interferon were demonstrated in homogenized lungs of Sendai virus infected mice as long as the virus was present. Similar concentrations could be produced by i.p. injection of Sendai virus or interferon. Alveolar macrophages from mice treated i.p. with interferon or Sendai virus phagocytized more actively than control macropages. From the present and earlier data it is concluded that interferon may have a direct effect on the Sendai virus infection. The total effect of virus pneumonia is a reduction of the lung macrophage antimicrobial activity, and therefore the phagocytosis-modifying effect of interferon produced in the lungs is probably of minor importance for the outcome of the disease.

Animals↗
PubMed1979

Uptake of non-opsonized E. coli by unstimulated mouse peritoneal macrophages.

A method is described for the study of phagocytosis of 32P-labelled, non-opsonized, viable E. coli by mouse peritoneal macrophages. Factors influencing the uptake, such as medium, number of bacteria and time of phagocytosis, were standardized. The kinetics of the uptake were studied by visual counting of bacteria and by measuring the distribution of radioactive labelling. The uptake of 32P by the macrophages is well correlated to the number of bacteria phagocytized. The amount of phagocytosis depends on the bacterial density of the medium and the time of phagocytosis. When the medium contains more than 10(9) bacteria per ml, the maximum phagocytic capacity is reached after 90 minutes.

Animals↗
PubMed1979

Screening for rubella antibodies by a single radial haemolysis test.

A commercially produced single radial haemolysis (SRH) test for rubella antibodies was compared to the standard haemagglutination inhibition (HAI) test. There was a generally good correlation between haemolysis zone and HAI titres except for a few small and intermediate zones of haemolysis which were not dependable. The haemolysis was determined by the presence of rubella antigen. The SRH test is technically simple and can be recommended for screening programmes. IgM antibodies could not be detected by SRH.

Antibodies, Viral↗
PubMed1979

Sensitivity patterns of bacteria and antibiotic usage at the National Hospital of Norway in 1976 and 1978.

During the first three months of 1976 and 1978 the sensitivity patterns of bacteria and the antibiotic usage at the National Hospital of Norway was recorded. The computerized results showed that bacteria isolated at the department of pediatrics was more resistant to penicillins. Isolates from two other departments did not differ very much in their sensitivity patterns. Comparing the sensitivity patterns, a tendency of increased sensitivity to antibiotics from 1976 to 1978 was seen. Exception was the increasing resistance to gentamicin. Furthermore, tobramycin was found less effective than gentamicin on our isolates. The antibiotics most widely used at the hospital are the penicillins which account for more than 50 per cent of the usage. From 1976 to 1978 the usage of antibiotics increased about 30 per cent. A more extensive use of penicillin V and G, and sulfamethoxazole/trimethoprim was responsible for most of the increase. No clear cut relationship between the antibiotic usage and the changes in sensitivity patterns of the bacteria from 1976 to 1978 was seen. Our work confirms, the usefulness of using "daily defined doses", as recommended by WHO, for estimating the antibiotic usage in a hospital.

Anti-Bacterial Agents↗
PubMed1976

A computer system for handling data from bacterial sensitivity testing.

A computer system for handling data collected from antibiotic sensitivity testing of clinical bacterial isolates is described. The system allows a rapid handling of the information collected, supplying the ward and laboratory with cummulative data on each patient. The bacteriologist and the clinician are thus suitably armed when creating a rational antibiotic therapy.

Computers↗
PubMed1976

Effect of antibiotics on interferon production in mice.

Neomycin, chloramphenicol, gentamycin, rifampicin and oxytetracycline were tested for their influence on virus induced interferon (IF) production in mice. Repeated intraperitoneal (i.p.) injections of antibiotics were given to produce significant serum concentrations during the time of IF production, induced by i.p. injections of Newcastle disease virus (NDV). IF titres in antibiotic-treated mice determined 6 hours after induction were compared to titres in control mice given NDV only. The IF production was not significantly modified in most of the antibiotic treated mice. Only the highest dose of chloramphenicol (2500 mug/mouse) appeared to cause a reduction in IF production (p less than 0.10). Addition of antibiotics in vitro did not alter the antiviral titres of IF.

Animals↗
PubMed1975

[Penicillin V].

Explore the source record for details and available documents.

Child↗