Epidemiological aspects of Crohn's disease in Clydesdale 1961-1970

A retrospective study of Crohn's disease has been carried out in Clydesdale covering the decade 1961-1970. Three hundred and fifty-seven patients had acceptable evidence of either acute ileitis or of chronic granulomatous bowel disease. Of those fulfilling the criteria for inclusion in the study of chronic disease, 95% had accurate pathological and/or operative documentation of the lesions. Overall, females outnumbered males by 1-6:1 but colonic disease alone tended to affect females, particularly those over the age of 50. The annual incidence of all forms of the chronic disease in both sexes has increased during the decade, but diagnosis of colonic disease alone increased two-fold in the latter half of the study.

Neurological and pathological effects of second lumbar spondylectomy and spinal column shortening in the dog

The second lumbar vertebra was surgically removed from 10 dogs, and the shortened vertebral column was stabilized by internal fixation with two types of plastic plates. Shortening of the spinal column was usually not associated with detectable loss of function or neurological deficit. Histological lesions, however, included widely disseminated axonal degeneration, gliosis, and atrophy of spinal nerve roots in the surgical area. The spinal cord adapted to shortening of the vertebral column by becoming intrinsically shorter, rather than be being displaced within the spinal canal.

Cardiac responses to snout immersion in trained dogs

1. Four dogs were trained to immerse their snout voluntarily for durations up to 30 sec. Indwelling instrumentation was implanted to measure blood flow velocity in the circumflex branch of the left coronary artery, to sample blood from the left atrium and coronary sinus for the determination of P(O2), P(CO2), pH, oxygen saturation and haemoglobin concentration, and to pace the heart. An index of myocardial oxygen consumption was calculated by multiplying the mean flow velocity by the arteriovenous difference in oxygen content.2. Mean coronary flow velocity decreased significantly during simulated diving by 26 +/- 27% (+/- S.D.). The range of decrease in seventeen out of twenty experiments was from -5 to -81%. Heart rate decreased by 48 +/- 7% and this bradycardia was abolished by I.V. atropine.3. Coronary sinus oxygen saturation increased significantly with snout immersion (three dogs) and arteriovenous difference decreased from 67 +/- 10 to 47 +/- 5%. The index of myocardial oxygen consumption decreased by 42 +/- 19%. This decrease was attenuated slightly by beta-blockade but was abolished by cardiac pacing in three out of four experiments.4. The present study indicates that the heart consumes oxygen at a considerably reduced rate during simulated diving and therefore plays a direct role in the overall conservation of oxygen. This response appears to result primarily from a negative chronotropic effect induced by increased vagal tone.

Directional Differences in the Colour Sensitivity of Daphnia Magna

1. The Daphnia compound eye movements can be driven by a flashing light.

2. The action spectrum for the threshold light intensity required to evoke this response depends on the orientation of the stimulus light beam with respect to the animal.

3. If the light falls on the eye through the top of the animal's head the action spectrum peaks at the low wavelength end of the spectrum, while if it falls on the eye through the side of the head the peak is in the yellow-green.

4. Eye movements cannot be evoked by illuminating any part of the animal except the compound eye so neither of these action spectra is due to a light receptor other than the compound eye.

5. Some anomalous action spectra in the literature on the behaviour of free-swimming Daphnia are accounted for.

Differentiation in breast cancer

Images

The biochemical and ultrastructural localisation of phosphoprotein-containing particles in lactating mammary glands of rats

Portions of rat mammary glands taken during lactation were subjected to homogenisation and to electron microscopy.

Biochemical evidence after homogenisation indicated that the phosphoprotein content was highest in the cellular supernatant fraction.

Electron microscopy revealed numerous spherical structures in the supernatant fraction and in milk.

These spherical structures were similar in size to the protein droplets that are found in the cytoplasm of mammary epithelium during lactation and which have been shown to contain abundant phosphoprotein.

This is further evidence for the hypothesis that the spherical protein particles contain casein.