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Biomedical subjects

A Wiik

Publications and source records attributed to A Wiik.

At least 127 records · Page 7Linked to original sources
PubMed1984

Autoantibodies and vascular events in essential hypertension: a five-year longitudinal study.

The relationship between serum autoantibodies and vascular events was investigated in 140 patients with essential hypertension during a five-year period. The influence of time upon incidence of autoantibodies was assessed in 55 normotensive controls of roughly the same distribution of age and sex. Thirty-four patients experienced a vascular event, which was fatal in 10 cases (7.1%). Eight of these 10 patients had autoantibodies in serum before the events, and the presence of autoantibodies at entry to the study tripled the five-year relative risk for vascular events. Antinuclear antibodies (ANA) and smooth muscle antibodies (SMA) especially contributed to this increased risk. The vascular events were followed by a significantly increased occurrence of ANA. In the control subjects no events occurred and no significant increases in the presence of autoantibodies were found during the five years. ANA and SMA positive sera showed no significant complement fixing properties, and the autoantibodies studied seemed to be secondary to tissue damage. Despite this, they seemed to reflect an ongoing injury of the vascular bed.

Adult↗
PubMed1984

Basal cyclic AMP levels in human blood mononuclear cells.

Basal cyclic AMP levels in blood mononuclear cells from healthy human donors has been studied. A great variation in cyclic AMP content ranging from below 2 to 20 pmol 10(-6) cells was seen. Incubation of the cells at 37 degrees C mostly showed a time-dependent decrease in basal cyclic AMP, levelling off after 16 h. When treated synchronously, cells from blood from the first sample of blood sampling contained more cyclic AMP than that of later samples. Presence of adenosine deaminase, theophylline or indomethacin influenced cyclic AMP concentrations in a non-consistent manner. Variations in cyclic AMP content may in some individuals be ascribed to early increase of cyclic AMP, in others to a progressive reduction in basal cyclic AMP during blood sampling, cell preparation and incubation.

Adenosine↗
PubMed1984

Immunochemical studies on an IgG lambda cryoglobulin in cold-induced urticaria.

A type I cryoglobulinaemia associated with cold-induced urticaria was demonstrated in a 64-year-old woman without primary disease. The cryoglobulin contained only IgG lambda as disclosed by immunofixation technique. Different physicochemical studies indicated that the IgG lambda component was monomeric at temperatures above 35 degrees C, but became polymerized below 35 degrees C. In addition crossed immunoelectrophoresis of plasma fibronectin from the patient showed a heterogeneous precipitate at low temperatures but a homogeneous precipitate at 25 degrees C indicating a complex formation at low temperature between IgG lambda and fibronectin. Fibronectin, however, was not essential for the cold precipitation of the cryoglobulin. The precipitation phenomenon at low temperatures was found to be a result of the physicochemical properties of the cryoglobulin itself unrelated to the antibody specificities tested. The importance of performing the immunochemical and physicochemical techniques at low temperature (7 degrees C) and at high temperature (35 degrees C) to gain knowledge of the nature of the protein, is emphasized. We conclude that only results obtained by relevant laboratory procedures might lead to correct classification and understanding of cryoglobulinaemia.

Aged↗
PubMed1984

Cerebrospinal fluid levels of cyclic nucleotides in meningitis and idiopathic polyneuritis.

Cyclic adenosine 3',5'-monophosphate (cAMP) and cyclic guanosine 3',5'-monophosphate (cGMP) were measured in cerebrospinal fluid (CSF) and plasma from 7 patients with bacterial meningitis, 9 patients with serous meningitis, 5 patients with idiopathic polyneuritis and 15 reference patients. A significantly (P less than 0.01) higher mean concentration of CSF cAMP was found in serous meningitis (33.8 +/- 12.5 nmol/l) compared to the reference group (20.2 +/- 4.0 nmol/l). No significant difference could be observed between the patients with purulent meningitis compared to the reference group. The CSF cAMP concentration (11.0 +/- 2.8 nmol/l) for idiopathic polyneuritis was significantly (P less than 0.01) lower than in the reference group. No difference in CSF levels of cGMP or in the cAMP/cGMP ratios were detected between the groups. Our data suggest that the ratio between cAMP concentrations in CSF and plasma may aid in the differential diagnosis between serous and purulent meningitis.

Adolescent↗
PubMed1984

Phagocytosis by normal polymorphonuclear leukocytes of immune complexes from serum of patients with Felty's syndrome and rheumatoid arthritis with special reference to IgE immune complexes.

Sera from patients with Felty's syndrome, rheumatoid arthritis (RA) and controls were investigated for the presence of immune complexes (IC) using phagocytosis by normal polymorphonuclear leukocytes and direct immunofluorescence technique. IC visible as large cytoplasmic inclusions were seen in 19 of 24 cases of Felty's syndrome, 3 of 16 cases of RA, and all 3 patients with extraarticular manifestations, and none of 21 control sera. IC containing IgG, IgA and complement C3 were found in nearly all positive cases. IgM IC were found in only 8 of the Felty's syndrome cases, IgE in 5 and beta-2-microglobulin in one case, respectively. A tendency to increasing number of large inclusion positive cells in vitro was found inversely correlated to the number of circulating leukocytes in the Felty patients at the time of serum sampling. In contrast, small cytoplasmic inclusions were found both in Felty's syndrome and RA patients and in some of the controls, and IgG and C3 were the most frequent constituents in these cases. As these inclusions were found in all groups it may have little significance. IgE IC as determined by a PEG precipitation technique were positive in the same 5 cases of Felty's syndrome with IgE containing inclusions, and in one case of RA with extraarticular manifestations. The complexed IgE amounted to about 3% of the total serum concentration of IgE. Phagocytosed IC may be involved in the pathogenesis of neutropenia and contribute to the inflammatory processes in Felty's syndrome.

Adult↗
PubMed1984

IgE class immune complexes in Felty's syndrome: characterisation of antibody activities in isolated complexes.

By means of a double polyethylene glycol (PEG) precipitation and PRIST technique IgE was detected in 3% PEG precipitates and in the immune complex enriched fractions purified by solid-phase Clq adsorption from sera of 11 of 20 patients with Felty's syndrome. No correlation was found between the occurrence of complexed IgE and total protein content of the immune complex enriched material. IgE rheumatoid factor and anti-IgE antibody activity were detected in some of the immune complex fractions. Serum levels of complement C3, C4, and factor B were low in IgE immune complex positive cases. Only 4 of 20 patients with articular rheumatoid arthritis had IgE-containing immune complexes.

Aged↗
PubMed1983

High serum beta-2-microglobulin levels and circulating immune complexes containing beta 2m and anti-beta 2m antibodies in Felty's syndrome.

Serum beta-2-microglobulin (beta 2m) levels, incidence and levels of anti-beta 2m autoantibodies, and quantity of circulating macromolecular complexes containing beta 2m were studied in patients with Felty's syndrome (FS), joint-restricted rheumatoid arthritis (RA), and healthy controls. The serum beta 2m concentrations detected in the FS group (6.95 +/- 2.9 mg/liter) greatly exceeded those of the RA group (3.4 +/- 1.2 mg/liter) and the control group (1.42 +/- 0.69 mg/liter). Autoantibodies to beta 2m were frequent in the FS group. Circulating complexes containing beta 2m, prepared by precipitation in 3% polyethylene glycol, were detected in 65% of FS and 35% of RA patients. In the majority of these cases the solid-phase C1q purified immune complexes also contained beta 2m. Detection of anti-beta 2m antibodies in a significant part of complexes containing beta 2m suggests the presence of specific immune complexes in this fraction of FS and RA patients.

Antibodies↗
PubMed1983

Immunological studies in two children with recurrent parotitis.

In two children with recurrent parotitis, labial salivary gland biopsies showed chronic sialoadenitis. Immunofluorescence studies disclosed deposits of immunoglobulins and complement in juxta-acinar small vessels. Case 1 had gluten enteropathy, IgA deficiency and high titres of antinuclear antibodies (ANA), and in vivo fixation of ANA to nuclei of different cells in lip, skin and jejunum was present. Case 2 showed deposition of IgM in the dermo-epidermal junction of the skin. These findings suggest that autoimmune reactivity and immune complexes may play a role in the pathogenesis of this disorder.

Adolescent↗
PubMed1983

Synovial fluid and blood monocyte influence on lymphocyte proliferation in rheumatoid arthritis and traumatic synovitis.

The influence of synovial fluid and blood monocytes on autologous lymphocyte proliferation in vitro was investigated in patients with rheumatoid arthritis (RA) and traumatic synovitis (TS). In cultures stimulated with PHA, PWM and ConA, thymidine incorporation by RA blood mononuclear cells (BMC) increased considerably in most cases after addition of 10% or 30% synovial fluid monocytes and a similar effect was seen after stimulation with Candida extract or PPD. A comparable helper activity was observed after addition of synovial fluid monocytes to monocyte-depleted blood cells in RA. The augmenting effect of synovial fluid monocytes was likewise demonstrated in TS patients. Synovial fluid mononuclear cells (SMC) from RA and TS patients displayed low proliferative responses to PHA and ConA in comparison with BMC, while the responses to microbial antigens were similar or greater. The proliferative activity of SMC or of monocyte-depleted synovial fluid cells after polyclonal and antigenic stimulation was not affected by addition of blood monocytes. This was observed in both RA and TS patients. It is concluded that the regulatory properties of synovial fluid monocytes in RA and TS do not explain the low proliferative responses of SMC to polyclonal activators.

Adult↗
PubMed1983

Use of protein A-positive Staphylococci as adsorbent in a radioimmunoassay for cyclic AMP and cyclic GMP.

A reproducible (SD less than 4%), sensitive (in the 5 to 50 fmoles range) and inexpensive radioimmunoassay has been set up for the quantitation of cyclic. AMP and cyclic GMP based on acetylation or succinylation of the test sample. Separation of antibody-bound from free ligand was achieved by adsorption to formalinized protein A-positive Staphylococci of the Cowan 1 strain. The quantity of adsorbent (5% suspension) needed per 300 microliters of antiserum (diluted 24 x 10(4)) was 10 microliters. The blank value was below 2% and separation could be run at room temperature or at 4 degrees C as convenient. The acetylation or succinylation procedure of the sample totally eliminated interference of test sample immunoglobulins with antiserum binding to the absorbent.

Acetylation↗
PubMed1983

Lack of evidence for granulocyte specific membrane-directed autoantibodies in neutropenic cases of rheumatoid arthritis and in autoimmune neutropenia.

With the purpose of detecting granulocyte-specific membrane-directed autoantibodies, IgG was isolated from 14 patients with Felty's syndrome, from 5 patients with rheumatoid arthritis associated with neutropenia, and from 3 rheumatoid factor positive patients with autoimmune neutropenia. By means of indirect immunofluorescence suspensions of leukocytes from healthy controls were tested for their ability to bind whole IgG fractions or F(ab')2 fragments of IgG isolated from the neutropenic patients. By this method, whole IgG preparations from neutropenic patients and normal controls were invariably found to bind to the surface of granulocytes and a minor proportion of lymphocytes. In contrast. F(ab')2 fragments of IgG from the neutropenic patients failed to bind to the surface of granulocytes. Both whole IgG fractions and F(ab')2 fragments displayed displayed antinuclear antibody activity ruling out the possibility of loss of antibody reactivity during the preparation of F(ab')2 fragments. The neutropenia seen in rheumatoid arthritis with or without splenomegaly thus does not seem to be induced by granulocyte-specific membrane-directed IgG autoantibodies, but rather by a non-specific attachment of IgG most probably in immune complex bound form to Fc gamma receptors on neutrophils which thereby acquire surface properties facilitating removal from the circulating blood cell pool.

Agranulocytosis↗
PubMed1983

Granulocyte specific antinuclear antibodies in ulcerative colitis. Aid in differential diagnosis of inflammatory bowel disease.

40 patients with ulcerative colitis (UC) and 35 patients with Crohn's disease (CD) were studied for the occurrence of granulocyte specific (GS-) antinuclear antibodies (ANA) and organ-non-specific (ON-) ANA. The predominant immunoglobulin class of GS-ANA in UC was IgG, present in 25% of the patients, but only in 3% of the patients with CD (p less than 0.02). ON-ANA were are in both groups and did not allow discrimination between these. Both GS-ANA and ON-ANA lacked complement-fixing properties. No relation was found between the types or titres of IgG ANA and sex, age, duration, disease activity or localization in the two groups of patients. The significance of our serologic observations in relation to these disease parameters has to be determined n larger prospective studies.

Adolescent↗
PubMed1983

Autoantibodies in patients with oral lupus erythematosus, lichen planus and leukoplakia. An aid in diagnosis.

Of 35 patients with oral discoid lupus lesions, 9 (25%) were diagnosed as Systemic (SLE) and 26 as Discoid (dle) lupus erythematosus. Antibodies to whole nuclei (ANAL), dsDNA (anti-DNA ab) and extractable nuclear antigens (anti-RNP ab, anti-Sm ab) as well as serum immunoglobulin levels (Ig) were determined in these patients, in 20 patients with reticular oral lichen planus (LP) and 20 with homogeneous oral leukoplakia (LEUK). High IgG ANA titres were found in the SLE cases, highly increased anti-DNA ab in 6 SLE cases (67%) and one DLE case (4%), slightly increased anti-DNA ab in 9 DLE (35%) but only two (5%) of the LP nd LEUK cases. The prevalence of autoantibodies and increased anti-DNA ab did not differ significantly between DLE cases with oral lesions only and those with cutaneous lesions as well. Increased Ig were present in 6 SLE (67%), 8 DLE (31%), and 3 LEUK (15%) but none of the LP cases. High ANA titres and/or elevated anti-DNA ab disclosed 8 of the 9 SLE and one of 26 DLE cases. Slightly elevated anti-DNA ab and elevated Ig indicated the diagnosis in 9 and 8, respectively, of the 26 DLE cases. It is concluded that determination of ANA, anti-DNA ab and Ig is of diagnostic importance in patients with verified or suspected oral discoid lupus lesions.

Adult↗
PubMed1982

Production and secretion of immunoglobulins by in vitro-activated human B lymphocytes.

Activation induced by pokeweed mitogen in cultures of mononuclear cells from human blood was followed sequentially by simultaneous quantitation of live cells, thymidine incorporation, cells displaying cytoplasmic, IgM, IgG, IgA or IgD, cells secreting IgM, IgG or IgA and cumulated IgM secretion. Maximal cellular activity was found after 7 days of cultures, with means of 16000 IgM-, 20700 IgG- and 9900 IgA-secreting cells per 10(6) originally cultured cells. The cumulated IgM secretion after 21 days of culture averaged 10400 ng per 10(6) originally cultured cells. A close correlation was found between the number of IgM-secreting cells and the cumulated IgM secretion.

Antibody-Producing Cells↗
PubMed1982

Functional characteristics of synovial fluid and blood mononuclear cells in rheumatoid arthritis and traumatic synovitis.

The activity of blood mononuclear cells (BMC) and synovial fluid mononuclear cells (SMC) from patients with rheumatoid arthritis (RA) and traumatic synovitis (TS) was assessed by means of [14C]thymidine incorporation and production of leukocyte migration inhibitory factor (LIF). When compared with normal controls, spontaneous LIF production by BMC was found in 5 of 9 TS patients, whereas spontaneous LIF production by rheumatoid arthritis BMC and by SMC from both patient groups was infrequently seen. ConA-induced LIF production by BMC and SMC from both patient groups did not differ significantly from that of normal controls. Thymidine incorporation by unstimulated SMC and BMC was low in both patient groups. After stimulation with polyclonal activators, SMC showed significantly reduced proliferation in comparison with BMC, but the responses to microbial antigens were equal to or higher than those of BMC. The proliferative responses of stimulated SMC from TS patients were higher than the responses displayed by stimulated SMC from RA patients.

Adult↗
PubMed1981

Possible role of histamine in rheumatoid arthritis. Treatment with cimetidine and mepyramine.

Basophilocytes from patients with rheumatoid arthritis (RA) responded to leukocyte nuclei from normal persons with histamine release; a similar histamine release induced by the nuclear components RNA and DNA has been demonstrated previously. A role of histamine in RA is also supported by the findings of clinical improvement during treatment with H1 and H2 antihistamines in six of 12 patients with RA in active phase, whereas four showed definite deterioration.

Adolescent↗
PubMed1981

Pseudothrombocytopenia. In vitro studies on the underlying mechanism.

In a prospective 9 month study at a medical department with special interest in immunology and rheumatology, 10 patients with spuriously low thrombocyte counts - pseudothrombocytopenia - were registered. The phenomenon was observed when the counting of platelets was performed on a Thrombocounter C apparatus or by manual counting using K2EDTA stabilized blood since platelet agglutination was considerably less pronounced when solution citratis glucosi fortis (ACD) was used as the anticoagulant. Results of our in vitro studies indicate that the mechanisms contributing to pseudothrombocytopenia involve the interaction of circulating immune complexes with platelet membrane Fc receptors causing agglutination. Fab'2-fragments of isolated patient IgG did not react with normal donor thrombocytes. This finding argues against agglutination due to true antiplatelet antibody activity.

Adult↗