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Biomedical subjects

O Ruuskanen

Publications and source records attributed to O Ruuskanen.

At least 145 records · Page 8Linked to original sources
PubMed1984

Impaired B lymphocyte function during open-heart surgery. Effects of anaesthesia and surgery.

B lymphocyte function in vitro was measured in patients undergoing open-heart surgery. Conventional balanced anaesthesia, or high-dose fentanyl anaesthesia was used. Pokeweed mitogen (PWM) induced lymphocyte transformation was depressed at the end of the operation, but the response to formalinized Staphylococcus aureus Cowan I (StaCw) was not. The numbers of immunoglobulin producing and secreting cells measured by an indirect protein A plaque-forming cell assay decreased after PWM-stimulation, but remained unchanged after StaCw stimulation at the end of the operation. IgG, IgM and IgA secretion by PWM- and StaCw-stimulated lymphocytes, into the culture medium, was depressed in the period after operation. Depressed immune functions occurred after open-heart surgery, but not in association with anaesthesia alone before surgery. The decreases were not mediated by hydrocortisone-sensitive suppressor cells. Minor differences between the two anaesthetic techniques were found in lymphocyte proliferative responses.

Anesthesia, General↗
PubMed1983

Intrafamilial spread of pertussis.

Intrafamilial spread of pertussis was evaluated in 21 families (97 individuals) of patients with whooping cough diagnosed by culture or by ELISA serology. During follow-up (average six months), an infectivity rate of 83% was established by an ELISA within these families. However, 46% of the secondary cases were asymptomatic. Most of the asymptomatic cases were in adults or vaccinated children. Unvaccinated infants had classic whooping cough and were exposed to pertussis by their vaccinated siblings or parents. The incidence of classic symptoms of pertussis decreased with age, and atypical pertussis was usually culture negative but rapidly diagnosed by measurement of the IgM- and IgA-class antibodies by ELISA.

Adolescent↗
PubMed1983

Serologic diagnosis of pertussis: comparison of enzyme-linked immunosorbent assay and bacterial agglutination.

An enzyme-linked immunosorbent assay (ELISA) and bacterial agglutination (BA) method for determining the presence of antibodies to Bordetella pertussis were compared on serum samples from 21 patients with whooping cough and their 76 family members. The overall diagnostic agreement between the two methods was 77%. The data for BA-detected antibodies correlated best with IgG and IgA antibodies to B. pertussis. All of the culture-positive patients showed serologic positivity in both assays during the follow-up. Pertussis was diagnosed by ELISA in most cases from the first serum sample. Both methods proved to be good diagnostic aids in culture-negative patients, although the value of BA is more retrospective because of the need for paired sera. The kinetics of IgM, IgA, IgG, and agglutinating antibodies to B. pertussis is presented.

Adolescent↗
PubMed1983

Immunoassay diagnosis of adenovirus infections in children.

Direct detection of viral antigen in nasopharyngeal secretions and stool specimens by radioimmunoassay and the determination of serum antibody responses by complement fixation and immunoglobulin class-specific enzyme immunoassay against the hexon antigen were compared for diagnostic efficacy in 52 children with acute adenovirus infections. The highest diagnosis rate (85% of the cases) was obtained by antigen detection in nasopharyngeal secretions. Adenovirus antigen was also detected in stools of 72% of the 18 patients tested. The immunoglobulin G (IgG) antibody enzyme immunoassay detected 77% of the cases, being more sensitive than the complement fixation test with a 67% detection rate. The IgM antibody response was variable with no clear correlation with the age of the patient or severity of the clinical symptoms. IgM antibody response was detected in 48% of the patients and had the normal transient course, with a persistence of the IgM antibodies of approximately 2 months. Determination of IgA antibodies gave a diagnostic increase in titer in 37% of the cases and was found less suitable for serological diagnosis. Because of the clinical importance of rapid laboratory diagnosis, the direct detection of viral antigen in nasopharyngeal secretions or stool or both should be used as the primary diagnostic test in adenovirus infections.

Adenoviridae↗
PubMed1983

Defective B cell function associated with inherited interstitial deletion of the short arm of the X chromosome.

The B cell function of a patient with low serum immunoglobulin (Ig) levels and with an interstitial deletion in the short arm of one of her X chromosomes (del(Xp] and the B cell function of her relatives were analyzed by indirect protein A plaque-forming cell (PFC) assay and by measuring immunoglobulin secretion in vitro by ELISA. B cells were activated by pokeweed mitogen (PWM) with or without hydrocortisone (HC) to inhibit HC-sensitive suppressor cells. The patient, her mother, and one sister, all of them having del(Xp), generated very few PFC induced by PWM, even in the presence of HC, whereas normal PFC responses were found in the patient's cytogenetically normal sisters. The B cells of the subjects with del(Xp) secreted very low amounts, if any, of IgA, IgG, and IgM. Co-culture experiments with B cells from del(Xp) subjects and normal OKT 4+ cells revealed no or very low Ig production. The function of the del(Xp) subjects' OKT 4+ cells was slightly reduced, whereas the activity of their OKT 8+ cells was normal. The cell subset analysis in the peripheral blood revealed decreased OKT 4+:8+ ratios in all del(Xp) subjects. The results indicate an intrinsic B cell defect with a possible concomitant immunoregulatory defect associated with del(Xp). Moreover, the results support the hypothesis that antibody production is at least partially controlled by genes located in the short arm of the X chromosome.

Adult↗
PubMed1983

B-lymphocyte function in cystic fibrosis.

The susceptibility of patients with cystic fibrosis to chronic, progressive bacterial pulmonary infections has not been adequately explained. We explored peripheral blood B-cell function in 21 cystic fibrosis patients and in normal controls. All patients were above 10 years of age, and chronically colonized with Pseudomonas aeruginosa. Spontaneous plaque-forming cells, which reflect B-cell differentiation into immunoglobulin-secreting cells in vivo, and plaque-forming cells formed after activation with pokeweed mitogen or staphylococci in vitro, were studied. Cystic fibrosis patients had significantly higher spontaneous plaque-forming cells than normal individuals. This difference was due to the increase of spontaneous plaque-forming cells than normal individuals. This difference was due to the increase of spontaneous plaque-forming cells in patients with less severe pulmonary disease, since patients with advanced pulmonary disease had numbers of circulating immunoglobulin-secreting cells, similar to normal individuals. Both groups of cystic-fibrosis patients have a significant impairment of B-cell differentiation in response to polyclonal activation in vitro. This functional abnormality could not be explained by the presence of increased numbers of adherent suppressor cells, or by the presence of increased suppression by T-lymphocytes. The implications of our data for the increased susceptibility to infection and for the development of antibody-mediated hypersensitivity reactions are discussed.

Adolescent↗
PubMed1982

Effects of indomethacin on lymphocyte proliferation, suppressor cell function, and leukocyte migration inhibitory factor (lmif) production.

The in vitro effect of indomethacin (IND) on PHA- and Con-A-induced immune responses was studied. The results showed that the enhancement of both PHA and Con A responses by IND does not significantly depend on the concentrations of mitogens or IND. A significant negative correlation was found between the initial PHA response and augmentation index, whereas there was a positive correlation between the initial Con A response and the enhancement of the Con A responses. Indomethacin significantly increased the Con-A-induced suppressor cell activity and PHA-induced leukocyte migration inhibitory factor production (LMIF), whereas the effects on the PHA-induced suppressor cell activity and Con-A-induced LMIF production were not significant. The findings indicate the indomethacin has a dual effect on PHA- and Con-A-induced immune responses probably reflecting intrinsic differences among T cells, for example, distinct lymphokines produced by different T-cell subpopulations.

Cells, Cultured↗
PubMed1982

Pneumococcaemia complicated by meningitis.

Meningitis developed in 3 of 14 children with occult pneumococcaemia; in 2 of them it developed while they were being treated with low doses of intravenous penicillin, in the third child it developed at a time when he was not being treated. All children with occult pneumococcaemia should be treated with intravenous penicillin as are those with pneumococcal meningitis.

Child↗
PubMed1982

Effects of theophylline on the neonatal immune response.

Theophylline has recently shown to affect lymphocyte reactivity. In view of its widespread use in newborn intensive care units, the effects of both lymphocyte proliferation and immunoglobulin production at varied theophylline concentrations were measured. In 12 adults and 10 term infants lymphocyte proliferation, as assessed by a whole blood micromethod, was significantly decreased in vitro at 7.5 micrograms/ml. Immunoglobulin production in adults was decreased, by both a plaque forming cell assay and a radioimmunoassay in vitro at 12.5 micrograms/ml. Ten premature infants on theophylline, mean serum level 7.8 +/- 0.4 micrograms/ml, followed for 3-5 wk, showed a slight increase in lymphocyte proliferative responses to pokeweed mitogen. These data demonstrate no in vivo suppression of lymphocyte proliferation in theophylline-treated neonates at low theophylline levels.

Humans↗
PubMed1982

Serological diagnosis of pertussis: IgM, IgA and IgG antibodies against Bordetella pertussis measured by enzyme-linked immunosorbent assay (ELISA).

Igm, IgA and IgG antibodies against Bordetella pertussis were measured by enzyme-linked immunosorbent assay (ELISA) with an ultrasonicate of formalin-killed bacteria (a mixture of strains 1, 2 and 1, 2, 3) as antigen and disposable polystyrene 9-cuvette blocks as the solid phase. The specificity properties of the assay were assessed by an inhibition technique. Of the microbes tested, only B. parapertussis was able to cause a significant inhibition. In addition, IgM and IgA antibodies against B. pertussis were only found in some sporadic cases of respiratory infections caused by other microbes. Sera, nasal swabs and cough plates were received from 198 patients with suspected whooping-cough. ELISA determinations were mostly made from only one serum sample of each patient. Paired sera were studied only from the culture-positive infants under 3 months of age. The number of positive cultures was highest in group under 3 months of age (41%), where the frequency of positive ELISA was lowest (20%). The use of paired sera strikingly increased the number of ELISA-positive individuals in this youngest patient group. In later life, the relationship between these tests changed: isolation was positive in only about 10% of the patients, whereas 29-64% yielded positive titres in ELISA. This study shows that pertussis ELISA is a valuable aid in the rapid diagnosis of pertussis, particularly of the atypical forms of the disease which mostly are culture-negative.

Antibodies, Bacterial↗
PubMed1982

Current status of pertussis and pertussis vaccination in Finland.

The pertussis vaccination programme was started in Finland in 1952. Since then the incidence of the disease has decreased. No major epidemics have occurred during the last two decades. The majority of the patients with pertussis are children of school age. Their disease is characterized by prolonged cough without whooping and it is difficult to diagnose. The patients with atypical pertussis are, however, the major reservoir for transmission of the disease to young infants, in whom it can be serious. Recently developed ELISA for measuring antipertussis IgM and IgA antibodies is a valuable aid in the diagnosis of these cases. Pertussis vaccination has been a subject of considerable controversy in recent years. The vaccine used in Finland has proved to be safe and effective. This observation emphasizes the need for careful comparison of the vaccines used in different countries.

Adolescent↗
PubMed1981

Thymic morphology during in vitro culture.

Morphology of guinea-pig thymic fragments was studied sequentially during in vitro organ culture by using light and electron microscopy and 3H-thymidine autoradiography. In culture the fragments became alymphoid. Thymic lymphocytes started to disappear first at the corticomedullary border, which gradually broadened, giving rise to the alymphoid epithelial fragments. As the lymphoid cells disappeared the thymic epithelium began to transform into a keratinized squamous epithelium. The keratinization started in the cells surrounding the Hassall's corpuscles, causing the enlargement of the corpuscles and finally total keratinization of the cultured epithelial fragments. In autoradiographic studies cell proliferation could be observed in uncultured thymuses at the cortical pericapsular area. In cultured alymphoid fragments labelled cells were distributed diffusely in the epithelium. Later labelling was concentrated to epithelial cells transforming to keratinized epithelium. Ultrastructural studies similarly showed transformation of the epithelial cells to squamous keratinized epithelium. The observation support the view that Hassall's corpuscles are derived from the keratinized thymic epithelium and that their existence is connected to the normal function of the epithelium.

Animals↗