Search PubMed⌕ Search

Biomedical subjects

F De Keyser

Publications and source records attributed to F De Keyser.

100 records · Page 6Linked to original sources
PubMedDate not supplied

Influence of the gut and cytokine patterns in spondyloarthropathy.

Clinical and histological studies have previously shown that spondyloarthropathy (SpA) patients can have subclinical gut inflammation. This gut inflammation is related to enterocolitis in Crohn's disease (CD) and may evolve to overt inflammatory bowel disease in a subset of these patients. Moreover, there is an intriguing clinical link between gut inflammation and peripheral joint inflammation. In order to explore immunologically these concepts, recent studies have characterized phenotypically and functionally the inflammatory cells in both the gut and the synovium of SpA patients and have provided a number of new insights. Firstly, they confirm histological and pre-histological alterations of the gut immune system in SpA, which are redundant of CD and which are linked to alterations of the peripheral joints. Secondly, both the acquired and the innate immune system contribute to these alterations, with an important role for both T cells and macrophages and their cytokines. Thirdly, interpretation of these data support the hypothesis that gut and joint inflammation in SpA are induced by the combination of an impaired anti-bacterial host defence and an uncontrolled pro-inflammatory response of the innate immune system. The insights provided by the study of the gut immunology in SpA have contributed to develop new therapeutic strategies, with TNFalpha blockade as prototype.

Cytokines↗
PubMedDate not supplied

Churg-Strauss syndrome presenting as polymyositis.

Churg-Strauss syndrome is a vasculitis-based pathology, predominantly characterized by asthma and eosinophilia. Histopathologically, the vessel wall infiltration contains a substantial proportion of eosinophils and extravascular granulomata can be demonstrated. We report a case of Churg-Strauss syndrome presenting as polymyositis.

Blood Vessels↗
PubMedDate not supplied

Detection and identification of antinuclear autoantibodies in the serum of normal blood donors.

The occurrence of antinuclear antibodies (ANA) in the serum of 485 healthy volunteer blood donors was assessed. Sixty two sera displayed nuclear immunofluorescence staining on Hep-2 cells using a polyvalent anti-Ig conjugate. In general, the titer of these antibodies was low (42/62 sera displaying a titer lower than or equal to 1:80). In only 23 sera were the ANA of the IgG isotype, which is the more disease-related immunoglobulin class of autoantibodies. In order to define the frequency of antibodies to extractable nuclear antigens and dsDNA within this population, sera were further analyzed by counterimmunoelectrophoresis. Western blot and the Crithidia luciliae assay. One serum displayed weak antids DNA reactivity; another serum had anti-SSA/Ro activity. On Western blot several patterns were found. They could not be identified with any of the available reference antisera.

Adolescent↗
PubMedDate not supplied

Interlaboratory variability of the antiperinuclear factor (APF) test for rheumatoid arthritis.

The antiperinuclear factor (APF) test is as sensitive and specific for rheumatoid arthritis as the classical rheumatoid factor tests. Five European laboratories decided to perform a consensus study on the interlaboratory variability of the APF test. They used different donor cells, different conjugates and different criteria for positivity. However, the results differed by not more than one two-fold dilution step, when expressed in international units using WHO reference rheumatoid arthritis serum as the standard.

Antibodies, Antinuclear↗
PubMedDate not supplied

Etiological factors and underlying conditions in patients with leucocytoclastic vasculitis.

This study concerns a retrospective analysis of 63 consecutive patients presenting with leukocytoclastic vasculitis at the Departments of Dermatology or Rheumatology of the University Hospital Ghent (Belgium) (period 1988-1993). The diagnosis of leukocytoclastic vasculitis was confirmed by histopathology in all cases. All patients were screened for underlying causes, including drugs, infection, systemic autoimmune disease or neoplasia. In 34 patients, an etiological factor was identified: drugs (5 patients), infection (6 patients), drugs or infection (4 patients), systemic autoimmune disease (10 patients), Henoch Shönlein (6 patients), neoplasia (2 patients) and cryoglobulinemia (1 patient). In the group of patients with leukocytoclastic vasculitis in the context of systemic autoimmune disease, 4 patients suffered from systemic lupus erythematosus, 2 from Wegener's disease, 2 from Behçet's disease, 1 from polyarteritis nodosa and 1 from rheumatoid arthritis. In the remaining 29 patients, no cause for the vasculitis could be identified.

Adolescent↗
PubMedDate not supplied

The pathophysiology of lupus erythematosus.

Systemic lupus erythematosus disseminatus in addition to the more restricted, lupus-like syndromes, is the consequence of an attack by the immune system on the cellular and nuclear structures of the body. These disorders are also frequently associated with disturbances of the coagulation cascade. In this review paper, the factors that provoke or enhance these disturbances are considered, as well as the way by which this provocative effect is exerted. An intermutual relation between various elements is described, whereby congenital factors (heredity, race) and non-congenital factors (sex hormones, pregnancy, environment, ultraviolet light, drugs, infection) play a role. These factors induce the activation cascade of the disease, via two different axes: on the one hand modifications in the DNA structure, on the other immune stimulation. This eventually results in tissue damage.

Causality↗
PubMedDate not supplied

Altered expression of alpha E beta 7 integrin on intra-epithelial and lamina propria lymphocytes in patients with Crohn's disease.

OBJECTIVE: To compare the expression of adhesion molecules on intestinal intra-epithelial (IEL) and lamina propria T cells (LPL) from ileum and colon, in patients with Crohn's disease (CD) versus healthy controls, with special reference for the alpha E beta 7 integrin. METHODS: IEL and LPL were obtained from 18 CD patients and 20 controls by enzymatic extraction, and subsequently characterized by flow cytometry for CD3, CD4, CD8, CD25, LFA-1 alpha (CD11a), CD44, alpha 4 and alpha E beta 7 integrin. RESULTS: In LPL of controls, a decreased CD4/CD8 ratio was noted in ileum compared to colon. This regional difference was accompanied by a higher expression of alpha E beta 7 integrin in ileum versus colon. In LPL from left hemicolon of CD patients, a decreased CD4/CD8 ratio was noted versus controls. alpha E beta 7 expression on T cells of LPL did not discriminate CD from controls. However, an overexpression of this beta 7 integrin member was observed on CD25+ T cell subsets from lamina propria of left hemicolon, in CD versus controls. Moreover, in IEL, profound alterations in alpha E beta 7 integrin were observed in CD, compared to controls. A decreased expression of alpha E beta 7 was noted in IEL of ileum of CD patients. This was also apparent in non-inflamed mucosa. CONCLUSION: The observed changes of alpha E beta 7 integrin expression in CD patients versus controls are of pathogenic relevance, especially the decreased expression of alpha E beta 7 in IEL of non-inflamed CD mucosa. This may be one of the earliest events in the pathogenesis of this disease.

Adolescent↗