The effect of exercise on normal splenic volume measured with SPECT.

In a study group of 20 healthy young men, splenic volume was determined with SPECT before and after exercise. A randomly chosen control group of 10 comparable men was studied similarly, but without exercise intervention. The mean splenic volume did not change significantly in the control group (i.e., from 292.9 ml to 282.1 ml [P = 0.75]). The mean splenic volume decreased 60.1 ml from 279.4 to 219.3 ml (21.5%) in the study group and this was highly significant (P = 0.01). Although exercise induced splenic autotransfusion is generally considered to be unimportant in humans, significant splenic contractility was observed with this technique. In the normal individual with a large spleen or with functional splenomegaly, the contractility response may become more important and can now be measured in a quick and easy manner.

Difference between splenic volume measured at necropsy and that measured in vivo by radionuclide tomography.

Reference values for splenic volume used in this study are based on necropsy measurements made in 1970. Because the volumes (measured by radionuclide tomography) seemed to be consistently greater than the necropsy values, the splenic volume in 35 healthy male volunteers ranging in age from 18-30 years (median age, 21 years) was studied. Their mean (SD) splenic volume was 281 (73) ml compared with 138 (34) ml in the reference group. The mean splenic volume in healthy volunteers seems to be significantly greater than in cadavers, and these results suggest that reference range for splenic volume in vivo should be revised.

Factors affecting the immunogenicity of Pasteurella haemolytica in mice.

An appreciable level of immunity from intraperitoneal infection with Pasteurella haemolytica was established in mice by using a vaccine prepared in a conventional bacteriological culture medium, with aluminium hydroxide gel as adjuvant. The level of immunity could not be elevated by using bacteria grown in tissue culture media, enriched brain heart infusion broth, the addition of serum to the media or by using bacteria that had been harvested in the logarithmic growth phase. Although various extracts of the bacteria elicited a distinct immunity, the immunogenicity of vaccines containing bacteria could not be enhanced by augmentation with those products. The potential application of the vaccine in cattle and sheep is discussed.