Search PubMed⌕ Search

Biomedical subjects

R A Thompson

Publications and source records attributed to R A Thompson.

At least 127 records · Page 7Linked to original sources
PubMed1980

A method for the estimation of the activity of the inhibitor of the first component of complement.

The activated first component of complement (CI) possesses an esterase activity in vitro which will hydrolyse an ester of tyrosine to release H+. The activity of the serum inhibitor of C1 esterase may be measured by monitoring its ability to prevent H+ release under standard conditions. This paper describes a method of measuring such activity, monitoring H+ release by the use of either an acid base indicator of pH meter.

Colorimetry↗
PubMed1980

Detection of monoclonal immunoglobulins by immunoelectrophoresis: a possible source of error.

The technique of immunoelectrophoresis (IEP) is widely employed in the qualitative analysis of serum immunoglobulins. The most commonly used support media are agarose or agar gels, but the mobility of immunoglobulins is different in these two media. The presence of a small amount of a cathodal monoclonal immunoglobulin G may not be detected on IEP in agar if it is masked by larger amounts of polyclonal immunoglobulin of the same class. In these circumstances the use of agarose imparts to the monoclonal protein a different mobility from that of the bulk of the serum IgG and allows its positive identification.

Agar↗
PubMed1980

Plasmapheresis in hereditary angioneurotic edema and systemic lupus erythematosus.

A patient had hereditary angioneurotic edema coincident with systemic lupus erythematosus. This condition resulted in loss of hair, arthralgia, leukoplakia, collitis, and a nephrotic syndrome due to proliferative glomerulonephritis. The renal lesion was resistant to treatment with high-dose prednisolone and cyclophosphamide; however, sustained remission occurred after plasmapheresis. The patient has remained well for over two years since this procedure.

Angioedema↗
PubMed1980

Recurrent bacterial meningitis in patients with genetic defects of terminal complement components.

Isolated genetic deficiencies of complement components in man are rare. We describe two kindreds with inborn deficiencies of either C5 or C6 in which both propositi presented with recurrent bacterial meningitis. Neisseria meningitidis was isolated from the cerebrospinal fluid of the C5-deficient patient and bactericidal activity against his autologous meningococcus was absent from whole fresh patients' serum despite a rising titre of complement-fixing antibody. The stimulated movement of normal leucocytes was impaired in the presence of C5-deficient serum but not in the presence of C6-deficient serum; neither deficiency reduced significantly the complement-dependent opsonization of Saccharomyces cerevisiae. HLA typing and complement component phenotyping showed no segregation with the complement defect in either the C5- or C6-deficient families. Normal individuals and apparent heterozygotes with approximately half the normal levels of the relevant component were found in both families, in keeping with an autosomal codominant inheritance of the defects.

Adult↗
PubMed1980

Gluten-sensitive diarrhea without evidence of celiac disease.

Eight adult female patients suffering from abdominal pain and chronic diarrhea which was often incapacitating and frequently nocturnal, had dramatic relief on a gluten-free diet and return of symptoms after gluten challenge. Previous nonspecific measures and a milk-free diet were ineffective. Multiple jejunal biopsies showed minor, but significant changes in cellularity which returned to normal on the gluten-free diet. Apart from a slight increase in jejunal cellularity, no immunological abnormalities were found after gluten challenge. Steatorrhea or other biochemical defects, common in celiac disease, were not found. It was concluded that these patients had a gluten-sensitive diarrhea, but had no evidence of celiac disease.

Adult↗
PubMed1979

Is faecal alpha 1-antitrypsin excretion a reliable screening test for protein-losing enteropathy?

Estimation of alpha 1-antitrypsin in random faecal samples has been suggested as a reliable index of intestinal protein loss. There was a poor correlation between faecal alpha 1-antitrypsin concentrations and simultaneously measured faecal loss of 51Cr-albumin in twenty adults with suspected protein-losing enteropathy. This indicates that faecal alpha 1-antitrypsin estimation may not be a valid screening test for protein-losing enteropathy.

Adolescent↗
PubMed1979

Long-term parenteral exposure to mercury in patients with hypogammaglobulinaemia.

Patients with hypogammaglobulinaemia commonly receive regular long-term replacement therapy with a concentrate of pooled normal human immunoglobulin G (IgG) containing an organic mercury compound (thiomersal) as a preservative. In 26 such patients the total estimated mercury dosage received ranged from 4 to 734 mg (mean 157 mg) over treatment periods of six months to 17 years (mean 6.5 years). Nineteen patients (73%) had raised urine mercury concentrations, but no correlation was found between urine mercury and the age of the patient, the IgG dose, or the duration of treatment. Urine mercury concentrations are often used to control exposure and evaluate risks in exposed subjects. Hence most patients with hypogammaglobulinaemia are theoretically at risk from mercury exposure, although no clinical evidence of toxicity is yet apparent.

Adolescent↗
PubMed1979

Epidemiologic survey of sylvatic plague by serotesting coyote sentinels with enzyme immunoassay.

The geographic distribution and areas of high sylvatic plague activity in California were verified by using coyotes (Canis latrans) as sentinel animals. Antibody levels against Yersinia pestis were tested using the enzyme-labelled antibody (ELA) test and the microtiter passive hemagglutination and hemagglutination inhibition. A survey using the ELA test indicated that the overall antibody prevalence among 143 coyotes was 21%. By geographic regions, the highest antibody prevalence was 27% among coyotes from mountain areas on the northern and eastern borders of the state. This was followed by 19% in the central coastal area and 12% in the central valley. Areas with a high prevalence of seropositive coyotes or high antibody levels in individual coyotes matched the four areas of human plague exposures reported in 1977 and 1978. These areas included the central Sierra mountains adjacent to Lake Tahoe, southeastern Kern County, the central coastal area and Scott Valley near the Oregon border. The ELA test appears to be a promising tool for future epidemiologic studies of plague.

Animals↗
PubMed1979

Genetic basis of acquired C4 deficiency.

A study of the family of a patient who had an SLE-like syndrome and an extremely low serum C4 revealed an inheritance of C4 types and HLA region markers which indicated that the patient had 60--70% of "normal" C4 level prior to the onset of disease. Thus the extremely low C4 level during her disease may result from a combination of genetically determined low normal C4 and increased consumption/hyposynthesis secondary to her SLE.

Adult↗
PubMed1979

Significance of serum complement levels in patients with gastrointestinal disease.

Levels of the serum complement components, C3 and C4, in patients with Crohn's disease, ulcerative colitis, and miscellaneous gastrointestinal disorders were compared with those of normal blood donors. Significant increases of both components were found in all three patient groups, the highest being in patients with Crohn's disease. Generally, levels of C3 and C4 were lower in patients with inactive rather than active Crohn's disease and ulcerative colitis. These results provide some evidence in support of an immunological basis for inflammatory bowel disease. However, in view of the frequent elevation of C3 and C4 in other gastrointestinal diseases, it is equally possible that the complement components are behaving as acute phase proteins.

Blood Donors↗
PubMed1978

Complement changes during exercise-induced asthma.

Two groups of asthmatic children, one with and one without a history of post-exercise wheezing, and one non-asthmatic adult, were exercised on a treadmill, and their complement levels were measured before and after exercise. The first group of patients had the most obvious fall in FEV 1 and all showed a slight rise in haemolytic complement following exercise. Two of the patients of the second group also had a rise in haemolytic complement. The C4 titre did not change in any of the asthmatic children who did not wheeze after exercise, but there were changes, albeit inconsistent, in the titres of C4 in four of the six patients who exhibited post-exercise wheezing. C3 breakdown products were not detected in any of the sera, following exercise. The role of complement in exercise-induced bronchospasm is not clear, but there does appear to be a greater lability of the complement system in patients who are susceptible to this form of provocation.

Asthma↗