Immunological studies in chronic atrophic gastritis and chronic (superficial) gastritis

Detection of autoantibodies, HLA typing and immunofluorescence studies on gastric biopsies were carried out in subjects with histologically proven chronic atrophic gastritis (CAG) and chronic superficial gastritis (CG). All were seronegative for parietal cell antibody and did not have pernicious anemia. Except for positive antismooth muscle and antimitochrondrial antibodies in one patient with CAG, autoantibodies (antinuclear, smooth muscle, mitochrondrial, parietal cell) were absent in patients with CAG and CG. Immunofluorescence studies showed that Ig-G and IgA were presented in the lamina propria of all cases with CAG or CG and of subjects with normal gastric histology. Ig-M was seen less often, in about half the cases. Complement C3 was an uncommon finding, being positive in only one case with CAG and one case with CG and in none of the cases with normal gastric histology. Fibrinogen was more commonly seen in patients with CG (5/5 cases) than in those with CAG (3/11 cases). Fibrinogen was found in one case with normal gastric histology. The most consistent fluorescence was obtained with antiparietal cell antiserum. All subjects with CAG showed negative or weak staining only. In contrast, subjects with CG and normal gastric histology had strong specific fluorescence. An increased frequency of HLA-A1 plus HLA-B8 was found in subjects with CAG (20.7% in controls; 40% in CAG).

Thermal properties of the collagen of jellyfish (Aurella coerulea) and their relation to its thermal behaviour

It has been reported elsewhere (Rigby 1968a, 1968b) that for a number of poikilotherms sudden changes occur in physiological behaviour at temperatures which are the same as the melting temperature of their molecular collagen. A more general statement, which includes the above observations, is that the upper limit of the environmental temperature for an animal corresponds with the melting tempera. ture of its molecular collagen. A number of workers have contributed to this idea and details may be found in Rigby (1968a). It is not suggested that collagen is uniquely involved in these events, although this may be so. No doubt other body proteins are altered at the same time. The useful point is that collagen is one of the few easily prepared body proteins with a characteristic melting point, and as such can serve as an indicator in studies concerned with the temperature relation of poikilotherms. For example, animals, which can be adapted to reproduce at higher or lower temperatures than is usual for them, may produce a collagen which shows a parallel alteration in its melting temperature. Such an experiment would afford a test of the general assumption that the constitution and properties of a protein are determined only by genetic coding (see also Ruda1l1968).