Biomedical subjects

U Böhm

Publications and source records attributed to U Böhm.

29 records · Page 2Linked to original sources

PubMed1979

Complexed rheumatoid factor measurements in sera, synovial fluids and in immune complex fractions.

Mild acidic treatment increases the rheumatoid factor titre of some sera and synovial fluids (SF) in rheumatoid arthritis (RA), juvenile RA (JRA) and most frequently in rheumatoid vasculitis. This unmasking of 'hidden' RF in serum and SF samples correlated with the RF-immune complexes (RF-IC) and complexed C4 present in the 3% polyethylene glycol (PEG) precipitates, indicating that by means of 'hidden' RF measurements RF-ICs are possibly detected. This method seems to provide a diagnostic tool for detecting RF-ICs in RA and other related diseases.

Antigen-Antibody Complex↗

PubMed1979

Immunoglobulin levels of tonsillar cells.

Immunoglobulin G, A and M contents of homogenized tonsillar lymphocytes were measured. Higher Ig values were found in adults than in children. Inflammatory processes increased the immunoglobulin levels of tonsillar lymphocytes. The changes in tonsillar IgG and IgA levels suggest the importance of local immunoglobulin production in the defence mechanism of tonsils. Two isolated IgA deficiencies were detected among the 85 patients.

Adolescent↗

PubMed1979

Radioimmune double PEG precipitation technique for detecting complexed IgE.

The presence of IgE in immune complex-enriched fractions prepared by 3% polyethylene glycol (PEG) precipitation was studied. The dissolved PEG-insoluble fraction was incubated with [125I]anti-IgE antibodies an then precipitated again with 3% PEG. Radioactivity in the washed pellets was taken as indicating IgE present in immune complex form. A calibration curve was constructed using artificially prepared IgE-anti-IgE complexes. The method developed may be useful to detect other components present in immune complex fractions.

Antibodies, Anti-Idiotypic↗

PubMed1979

Rheumatoid factors bind beta 2 microglobulin. Detection of beta 2 microglobulin-complexes in rheumatoid arthritis.

beta 2 Microglobulin binding rheumatoid factors and occurrence of complexed form of beta 2 microglobulin were found in rheumatoid arthritis (RA) by radioimmunological methods. 1. As related to the appropriate values of control sera and osteoarthritic synovial fluids, one of the six sera and five of the six synovial fluids of RA patients exhibited increased binding activity for 125I-beta 2 microglobulin, 2. Rheumatoid factors (RF) purified by means of immunoadsorbent bound beta 2 microglobulin; 3. Both 19S and 7S components of sera, synovial fluids and purified RF samples had beta 2 microglobulin binding activity, which was inhibited by an excess of unlabeled beta 2 microglobulin; 4. Complexed (3% PEG 6000 insoluble) beta 2 microglobulin was found in three of fourteen sera and in twelve of fourteen synovial fluids of RA patients. Level of complexed beta 2 microglobulin was independent of its total concentration in the original samples; 5. In the fraction of synovial fluids enriched immune complex the amount of beta 2 microglobulin was in positive correlation with quantity of RF. Presumable immunological and pathological significance of "anti-beta 2 microglobulin"-like cross-reactive RF antibodies is discussed.

Arthritis, Rheumatoid↗

PubMed1978

Clinical immunological study of T lymphocytes and EA rosette forming cells in tonsils.

Tonsillar E and EA rosette forming lymphocyte subpopulations were studied in 120 tonsillectomized patients. T cell ratios was usually lower in the tonsils than in the blood. EA binding cells were studied with indicator systems of human or rabbit antibody sensitized red cells, respectively. Poorly sensitized human RBCs (EArabbit) bind much better to tonsillar cells than to blood lymphocytes and so this system proved to be specially suitable to study tonsillar EA binding cells. Increase in E and EA rabbit rosette forming cell frequencies were found with the age of patients. Decrease in percentage of T cells and EA rabbit rosette binding cells were found with high frequency of acut tonsillitis and with clinical sysmptoms of chronic local inflammation. The variation of these lymphocyte subpopulations with the local tonsillar inflammatory processes suggest a considerable clinical immunological role of local T cells and of this portion of Fc receptor postive lymphocytes.

Adenoids↗

PubMed1978

[Study of C3 and C4 complement components of synovial fluids in connective tissue diseases (author's transl)].

C3 and C4 levels and the relative concentration of C3 degradation products were measured in fifty pairs of synovial fluids and sera of patients who suffered from different connective tissue diseases. Inverse correlation between C4 level and C3 breakdown products were found in synovial fluids of different groups. Compared to the other groups of patients, the highest increase of C3 degradation was found in RA. patients and it occurred in the SF all of these patients. In arthrosis cases we failed to find any degradation of C3. Of the seven investigated ankylosing spondylitis only two showed some degree of activation of C3 in the SF. Our results suggest that the occurrence and degree of degradation of C3 complement component is a valuable laboratory parameter in the study of connective tissue diseases.

Arthritis↗

PubMed1977

Differential binding activity of EA receptor bearing human lymphocyte subpopulations.

Two types of EA rosettes were studied in rheumatoid arthritis patients and control subjects. Heterologous (rabbit) and homologous (anti-D) antibody sensitized human red blood cells (EAr and EAh, respectively) were used for examining the EA binding capacity of human lymphocytes. Both control and rheumatoid arthritis blood samples yielded significantly lower EArRFC levels as compared to the percentage of EArRFCs, the difference being even more expressed with control lymphocytes. No difference, however, was observed in the case of tonsillar lymphocytes, as equal rosette levels were reached in both systems used. Introduction of immunosuppressive therapy resulted in a temporary dissociation of the two rosette values EAr and EAh binding lymphocytes were differently affected by aggregated human IgG, only the latter ones being inhibited, contrasting with the equal inhibitory action of purified Fc fragments. Reducing the density of anti-D antibodies on the surface of erythrocytes, the EAh rosette count dropped to the level of EAr RFCs. The data suggest an activity-depending Fc receptor distribution resulting in different binding capacity for more or less sensitized indicator RBCs.

Animals↗

PubMedDate not supplied

Role of cellulose in wood dust-induced fibrosing alveo-bronchiolitis in rat.

Our experiments suggest that in the development of plant dust-induced fibrosing alveobronchiolitis--Scadding's fibrosing alveolitis--the cellulose content of plant dusts has a decisive aetiological role. Namely, the wood dust (pine) and the cellulose induced morphologically identical granulomatous inflammation and fibrosis, whereas the fibre-free extract of wood dust did not cause pathological changes in the lungs. The induction of H2O2 and superoxide anion production, shown in vitro in leucocytes, probably has an important role in the development of fibrosis.

Animals↗

PubMedDate not supplied

Effectiveness and safety of ultrasonic atherosclerotic plaque ablation: in vitro investigation.

Ultrasound energy was applied to 137 segments of human cadaver atherosclerotic arteries, 90 with calcified and 47 with noncalcified atheromatous plaque, and to 100 segments of healthy swine aorta. The average depth of penetration was dependent on the forward force of the ultrasonic probe, the duration of treatment, and the degree of atherosclerosis. There was one perforation of a fibrous plaque using a forward force of 2 Newton and 45 sec of application time. Injury of healthy intima was minimal. It is concluded that catheter-delivered ultrasound is effective and safe for the disintegration of atherosclerotic plaques. Presently, the main limitations of the system are the lack of flexibility and steerability.

Angioplasty, Balloon↗

PubMedDate not supplied

[Defects in opsonization activity of the serum of patients with chronic arthritis].

The opsonizing capacity of sera from 22 patients with rheumatoid arthritis (RA), from 14 with psoriatic arthritis (AP), from seven with ankylosing spondylitis, and from healthy control persons was investigated by luminol-dependent chemiluminescence, induced during yeast phagocytosis of normal polymorphonuclear leukocytes. The chemiluminescence response using opsonizing sera was compared to that induced by no-opsonized yeast and the opsonizing capacity was expressed as a percentage. For the opsonization, fresh native serum, in some experiments Mg2+-EGTA and EDTA-treated serum, was used. In RA and AP sera, a significantly diminished opsonizing capacity (p less than 0.005) was observed. In healthy controls and in SPA patients, the opsonizing capacity of their sera was over 200%, while in seronegative RA patients, it was only 175%, in seropositive RA 125%, and in AP 150% was measured. There was no correlation between opsonizing capacity and complement or immunoglobulin content of the investigated sera. The amount of C3b, IgG and IgM covalently bound to yeast particles was determined, too. Yeast particles bind significantly less (p less than 0.01) IgG when opsonized with RA and AP sera, while a higher relative amount of IgM (p less than 0.01) was bound to yeast incubated in the sera of seropositive RA patients. No significant differences in the C3b binding were observed.

Arthritis↗

PubMedDate not supplied

[Functional analysis of immune complex-rich serum fractions in autoimmune diseases by in vitro C3 activation of fresh blood].

A method, measuring the activity of circulating immune complexes, based on C3 conversion of fresh human plasma by means of 3 per cent PEG precipitable immune complex-rich sera fractions is reported. Sera of patients suffering from autoimmune diseases of the connective tissue as well as of healthy controls were investigated. In case of standardised protein concentration of immune complexes, significantly low C3 conversion frequency of the isolated fractions has been observed in the control group as compared to the examined patients (rheumatoid arthritis with and without extraarticular manifestations, or juvenile chronic arthritis, or systemic lupus erythematosus). PEG fractions of RA with extraarticular manifestations induced the significantly highest C3 splitting. It is assumed that immune complexes will show a distinct interaction with the complement system also in vivo, and are therefore directly implicated in the systemic course of the disease process.

Arthritis, Juvenile↗