PubMed Health⌕ Search

Biomedical subjects

F G Simpson

Publications and source records attributed to F G Simpson.

34 records · Page 2Linked to original sources

Leucocyte migration inhibition test in coeliac disease - a reappraisal.

Results of the direct leucocyte migration inhibition (LMI) test using gluten fraction III as antigen were unaffected by incorporation of puromycin into the culture medium at concentrations shown to prevent lymphokine mediated inhibition. Results of the LMI test performed with purified polymorphs were similar to and correlated with results of the standard LMI test using mixed leucocytes in both coeliacs and controls. The addition of purified T lymphocytes did not increase migration inhibition. Normal leucocytes incubated with serum from coeliac patients and washed showed marked migration inhibition when incubated with gluten fraction III. This sensitisation of normal leucocytes was prevented by preincubation with aggregated human IgG. These results suggest that leucocyte migration inhibition by gluten in coeliac disease is not due to lymphokine production by sensitised lymphocytes but is caused by cytophilic antibody.

Adolescent↗

Small intestinal ulceration: diagnostic difficulties in relation to coeliac disease.

Seven cases of ulceration of the small intestine are described and the relationship to coeliac disease is discussed. Evidence for coeliac disease is found in all cases but is less strong in some than in others, and coeliac disease was proved in only two cases. The ulcers were examined histologically in each case and in three cases were associated with malignant histiocytosis but the others showed only non-specific chronic inflammation. This suggests a spectrum of disorders with an inconsistent relationship to gluten sensitivity and small intestinal lymphoma.

Adult↗

Jejunal biopsy and lymphocyte co-culture in coeliac disease.

Jejunal biopsies from 13 patients with treated coeliac disease were maintained in organ culture for 24 h with and without the addition of gluten fraction III, in each case with and without autologous peripheral blood mononuclear cells. Biopsies cultured with gluten alone or with lymphocytes alone showed no significant reduction in mean enterocyte height compared with those cultured in control medium, but those cultured with both gluten and lymphocytes had significantly lower enterocyte height than control biopsies, than those cultured with gluten alone, and than those cultured with lymphocytes alone. These results demonstrate that the combination of gluten and lymphocytes is more toxic to treated coeliac mucosa in vitro than either one alone and support the suggestion that immune reactions to gluten may be important in the pathogenesis of the mucosal lesion of coeliac disease.

Adult↗

Splenectomy causes auto-antibody formation.

Serum from 45 splenectomised patients was screened for 8 auto antibodies and compared with controls, either age and sex matched (35) or the same patients measured before splenectomy (10). Sixteen splenectomised patients had demonstrable auto-antibodies compared with 7 controls (p less than 0.05). Three patients who did not have auto-antibodies before splenectomy developed them after an interval of a few months. It is suggested that splenectomy-leads to loss of suppressor cell activity and this permits the development of auto-antibodies.

Adolescent↗

Cell-mediated immunity to dietary antigens in coeliac disease.

By means of the leukocyte migration inhibition test a significant depression of migration index (indicating increased immunity) was found in 10 untreated coeliac patients compared with 24 control subjects with the dietary antigens bovine serum albumin (BSA) and egg white but not with milk. The degree of immunity was similar to that obtained with gluten fraction III as antigen. Treatment with a gluten-free diet led to a decrease in immunity to egg white and BSA, but immunity to gluten fraction III was increased in the early months of treatment.

Adolescent↗

Suppressor cell activity, splenic function and HLA B8 status in man.

The enhanced proliferative response of peripheral blood lymphocytes (P.B.L.) to Concanavalin A (Con A) occurring after a 24 hr period of incubation was used as the basis of a suppressor cell assay and the results expressed as a suppressor index (S.I.) which if low implies impaired suppressor cell activity. S.I. was measured on P.B.L. from 26 patients with coeliac disease and defined splenic function, 8 patients with splenic atrophy not associated with coeliac disease, 30 patients after surgical splenectomy, and 52 controls. S.I. was lower than control in the splenectomy group (P less than 0.01) and in the coeliac group, but coeliacs with splenic atrophy were no different from coeliacs with apparently normal splenic function, nor were the non-coeliac splenic atrophy group different from control. Coeliacs with the HLA B8 gene had lower S.I. than those without, as did controls. Suspensions of cells from spleens removed at laparotomy demonstrated suppressor activity but this was no more marked than in P.B.L. It is concluded that the intact spleen is required for normal activation of suppressor cells in man, but this function is retained in splenic atrophy, and that the HLA B8 gene is associated with low suppressor cell activity in coeliac disease and in health.

Celiac Disease↗

Blood viscosity after splenectomy.

Blood viscosity and its contributory factors--namely, plasma viscosity, fibrinogen concentration, packed cell volume, red-cell deformability, and platelet count--were measured in 20 asymptomatic patients after splenectomy and compared with those in controls. Whole-blood viscosity was significantly increased after splenectomy and was associated with increased platelet count and, more importantly, decreased red-cell deformability. Blood viscosity was measured in six patients before and after splenectomy and in each an increase in viscosity occurred that did not occur in patients who underwent laparotomy without splenectomy. these findings suggest that the inclusions and protein complexes within the red cell that are normally removed by the spleen decrease red-cell deformability and lead to an increase in blood viscosity. This may account for the observed increase in deaths from ischaemic heart disease many years after splenectomy.

Adolescent↗

Preliminary evaluation of a single-day tubeless test of pancreatic function.

The test for pancreatic exocrine function using N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BTP test) does not require duodenal intubation, but misleadingly abnormal results often occur in patients with liver or bowel disease because the p-aminobenzoic acid (PABA) released by chymotrypsin hydrolysis of the peptide either is not conjugated or is malabsorbed. This study evaluated a modified BTP test, using a tracer dose of 14C-PABA to eliminate misleading results, to assess exocrine function from a single six-hour collection of urine. The test clearly distinguished all patients with pancreatic steatorrhoea from normal subjects and identified patients with less severe pancreatitis as often as did the Lundh test. Furthermore, in patients with bowel or liver disease the misleadingly abnormal results of the unmodified BTP test were eliminated by the modified test in all but one case. These findings suggest that the modified BTP test provides a practical alternative to conventional tests of pancreatic function that entail duodenal intubation.

4-Aminobenzoic Acid↗

HLA-B8 and cell-mediated immunity to gluten.

The leucocyte migration inhibition (LMI) test was used as an indicator of cell mediated immunity to gluten fraction III in 30 healthy controls and 58 patients with adult coeliac disease and the results related to HLA status and duration of treatment with a gluten-free diet. HLA-B8 controls showed significantly lower leucocyte migration indices, indicating greater immune response, than non-HLA B8 controls. Untreated coeliacs showed no difference from HLA-B8 controls. There was no difference between results from HLA-B8 and non-HLA-B8 coeliacs. Leucocyte migration was even lower in coeliacs early in treatment but rose after treatment for over one year. These results may reflect an immune response gene for gluten in linkage disequilibrium with HLA-B8. The increased immune response to gluten as measured in this test cannot be the sole factor in aetiology of coeliac disease. Furthermore, it is necessary to re-evaluate earlier results of cell-mediated immunity in coeliac disease with reference to HLA status of the controls.

Celiac Disease↗

Prospective study of thrombophlebitis and "pseudothrombophlebitis".

43 non-surgical patients presenting with calf pain and a clinical diagnosis of deep venous thrombosis (DVT) were studied by arthrography, venography, and ultrasound. Only 14 had venographic evidence of DVT; 5 of these had popliteal cysts, which in 4 cases probably contributed to symptoms. 11 patients had popliteal cysts and normal venograms, and 9 of these cysts were thought likely to be the cause of the symptoms. In 18 patients all investigations were normal. Physical signs were not helpful in distinguishing between the three groups of patients. Ultrasonography detected only 2 of the 16 popliteal cysts. Popliteal cysts should be considered in the differential diagnosis and as a possible coexisting condition in patients suspected clinically of having DVT. Also, the finding of a Baker's cyst should not deter one from doing a venogram.

Adolescent↗

Radio-opaque pellets as faecal markers for faecal fat estimation in malabsorption.

Thirty-seven patients undergoing routine investigation for malabsorption were given radio-opaque pellets (ROP) which were compared with polyethylene glycol and chromic oxide as continuous faecal markers. Percentage recovery of all markers showed a wide range. The recovery of all markers was very similar, and radio-opaque pellet-corrected daily faecal fat correlated very closely with PEG-and chromic oxide-corrected fat results. Estimation of ROP is precise, simple, and minimises faecal handling. ROP are suitable for routine use in faecal fat studies and have advantages over markers used at present.

Chromium↗

Radiation pancreatitis: a clinical entity?

2 cases of pancreatic disease in patients with malabsorption following small bowel radiation injury are reported. It is suggested that the pancreatic disease present in these patients occurred as a result of previous radiotherapy.

Humans↗