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Biomedical subjects

C Charland

Publications and source records attributed to C Charland.

5 recordsLinked to original sources
PubMed1979

Effects of sulfasalazine on selected lymphocyte subpopulations in vivo and in vitro.

Sulfasalazine has proven to be an effective agent in the therapy of inflammatory bowel disease (IBD). Despite long and widespread usage, the mechanism of action of this drug is still not understood. Several investigators have suggested that the drug might act as an immunosuppressant. To examine this possibility, an in vivo study was undertaken to ascertain any quantitative change in the circulating T cells, Ig-bearing B cells, and complement receptor-bearing lymphocytes (CRL) of patients before and during therapy with sulfaslazine. Concomitant responses to skin test antigens were also evaluated. In vitro studies with control cells were performed to determine the influence of sulfasalazine and its components (sulfapyridine or 5-aminosalicylic acid) on the extent of antibody-dependent cellular cytotoxicity (ADCC), as well as on the number of T cells and CRL. Results indicate that neither sulfasalazine nor either of its components quantitatively alters those subpopulations of circulating mononuclear cells studied in vivo or in vitro--nor are these compounds responsible for any functional inhibition of ADCC.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1979

Circulating Clq binding complexes in inflammatory bowel diseases.

To determine whether circulating immune complexes are present in the sera of patients with inflammatory bowel disease (IBD), a 125I-Clq binding assay was performed. Of the 55 IBD serum samples tested, the 24 ulcerative colitis samples demonstrated significant binding (33.1 +/- 8.3%, p = 0.02), whereas the 31 Crohn's samples bound essentially normal amounts (29.2 +/- 7.4%). A positive control group consisting of 27 patients with rheumatoid arthritis was also studied. Sera from 4 patients wiht IBD and colonic cancer when tested, bound 40.2 +/- 8.0% of the available 125I-Clq, while 10 patients with previous colectomies and ileostomies gave results similar to those of 15 healthy controls and 11 patients with irritable colon.

Antigen-Antibody Complex↗
PubMed1978

Skin test reactivity in inflammatory bowel disease in the United States and Czechoslovakia.

Inflammatory bowel disease (IBD) patients in the United States of America (USA) and Czechoslovakia (CSSR) were categorized by clinical, pathological, and radiological criteria as having Crohn's disease (CD) or ulcerative colitis (UC) and were tested with five skin test antigens [Candida, mumps, purified protein derivative (PPD), streptokinase-streptodornase (SK-SD), and trichophytin] at two different dilutions in an attempt to elicit some evidence of anergy. No significant differences were encountered between the USA and CSSR populations or between any patient group and its controls.

Allergens↗
PubMed1976

The subpopulations of circulating white blood cells in inflammatory bowel disease.

A detailed analysis of the species of lymphocytes was carried out in 58 patients with inflammatory bowel disease (IBD). These individuals were further divided into 31 with Crohn's disease (CD) and 27 with ulcerative colitis (UC). There were 13 CD patients with only small bowel involvement called "regional enteritis" and 18 who had some degree of colonic involvement called "ileocolitis". Similarly, the UC group was subdivided into 9 patients with disease confined to the rectosigmoid area called "proctosigmoiditis" and 18 with more extensive involvement called "universal colitis". We also studied 13 patients who had undergone previous colectomy and ileostomy and 78 healthy age- and sex-matched controls. Although there was no increase in the absolute number of lymphocytes in patients with ileocolitis and universal colitis, the percentage of these cells was decreased because of an increase in both polymorphonuclear leukocytes and monocytes. In IBD and its subgroups, mean T lymphocytes, determined by the sheep red blood cell rosette technique, were not significantly different from the controls either in percentage or absolute number. Furthermore, no difference was noted between UC and CD. However, there seems to be a subpopulation of patients with UC or CD whose T cells are reduced below 1 SD of the mean. There was also no difference in the number of immunoglobulin-bearing B cells in both diseases; however, when the B cells were enumerated by their ability to rosette with antibody-complement-coated sheep cells (EAC), we found a marked decrease in percentage (P less than 0.001) and absolute number (P less than 0.0005) relative to the control population. The decrease bore a direct relation to the severity of the disease process and, although more marked in patients with UC, was present in CD also.

B-Lymphocytes↗