CELLULAR TYPES IN ACUTE LEUKAEMIA: DIAGNOSIS AND SIGNIFICANCE.
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Two independent observers, one using haematological and the other histological methods, analysed material from 68 patients with acute leukaemia. A correct diagnosis of the cell type of leukaemia was made in 70% of cases by haematological methods, and in 83% of those cases histological examination gave the same result. In two-thirds of the haematologically equivocal cases histological examination provided a positive diagnosis. The finally undiagnosed cases amounted to 12% of the total. The types so diagnosed could not be correlated with any clinical features. Differentiation of the cell types in acute leukaemia showed that children with granulocytic types of acute leukaemia survived for shorter periods than those with other types but in adults the type of cell had no significance when related to survival. In adults the immediate prognosis for all cell types was relatively bad. The unfavourable prognosis attached to a high initial leucocyte count was confirmed. (+info)
THE MICROSCOPICAL APPEARANCES OF HUMAN PERIPHERAL ARTERIES DURING GROWTH AND AGING.
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Twelve peripheral arteries are described in 59 patients of all ages. Accumulation of ground substance in the media, accompanied by small foci of calcification of the internal elastic lamina, was found in the large leg arteries of young adults, and progressively in a wider series of arteries throughout life. This picture showed no relationship to hypertension, to Monckeberg's sclerosis, or to the development of atheroma. A notable quantity of ground substance may be a feature of early intimal development, and of a thickened intima in adult life, and probably the major constituent of an organizing thrombus. Organizing thrombi were apparently incidental findings at several sites even in young adults, and showed no association with the state of the arterial wall beneath the lesion, the wall being in fact normal, though accumulated mucopolysaccharide was always present. Atheroma increases with age, and its focal incidence gives way to confluence in the arteries of the leg. Occlusive peripheral artery atheroma was found only in cases where the cause of death was severe atheroma, e.g., coronary artery disease and abdominal aortic aneurysm, or in myxoedema, in which the incidence of occlusive lesions may differ from that in severe generalized atheroma. Elastic tissue is described in all coats of the artery wall, with some variants of the common pattern. The musculo-elastic cushion is not seen after adolescence, and it is suggested that the cushion represents the growing point of the artery. Longitudinal muscle bundles are almost confined to the popliteal artery, where they may form an essential buttress for a large branching artery subject to unusual external stresses. The functions and origin of the ground substance are discussed. (+info)
THE CONTROVERSIAL AND DYNAMIC OVARY.
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The ovaries from 75 females ranging in age from the newborn to 96 years were subjected to histologic scrutiny. Ageing phenomena comprising the gonad's life-long metamorphosis were documented. The cause of menopausal ovarian failure is twofold: (1) Ovarian vessel wall thickening and hyalinization as the cardiovascular system ages reduces perfusion of the gonad. (The blood supply of the ovaries is well designed to permit mobility but longevity of function is sacrificed.) (2) Gradual replacement of egg- and hormone-producing cells by fibrous tissue. This scar tissue accumulates as a result of ovulation and pregnancy and is less efficiently removed from the ovary in the later fertile years. By inhibiting ovulation, the oral contraceptives will likely delay the natural senescence of the ovary. More basic research is indicated to elucidate the mechanism of oogenesis. (+info)
A STUDY OF GRANULES AND OTHER CHANGES IN PHASE-CONTRAST APPEARANCE PRODUCED BY CHEMOTHERAPEUTIC AGENTS IN TRYPANOSOMES.
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The morphological changes produced by four series of organic trypanocidal drugs have been studied by quantitative and by qualitative methods using phase-contrast and fluorescence microscopy. Basic drugs were absorbed rapidly into the region of the kinetoplast; acidic drugs did not affect this region. Faint granules, which were present in some trypanosomes before the administration of drugs, absorbed the drugs and increased in contrast relative to the cytoplasm. Hydroxystilbamidine, quinapyramine, related compounds, and possibly also suramin produced additional granules which did not contain drug. These additional granules are similar to the granules (volutin granules) which occur in trypanosome infections (not treated with drugs) when trypanosomes are about to be cleared from the blood. Homidium did not produce additional granules. (+info)
QUANTITATIVE STUDIES ON PIGMENT MIGRATION AND LIGHT SENSITIVITY IN THE COMPOUND EYE AT DIFFERENT LIGHT INTENSITIES.
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Comparative electrophysiological and histological studies were made on the functional significance of the secondary iris pigment migration for the sensitivity of the eye in the noctuid moth Cerapteryx graminis. The pigment position at different adapting light intensities was studied as well as the influence of different positions on the sensitivity of the eye. Adapting light intensities above a certain value hold the pigment in light position. At a 3 log units lower intensity the pigment is brought into dark position and at light intensities between these limiting values the pigment attains intermediate positions. The results indicate that at light intensities between the limiting values the pigment shifts closely follow the changes in intensity of the environmental light. With the pigment in dark position the eye is about 1000 times more sensitive than when the pigment is in light position, there being a close relationship between the sensitivity of the eye and the position of the pigment at intermediate positions. (+info)
STUDIES ON ANTIBODY PRODUCTION X. MODE OF FORMATION OF PLASMOCYTES IN CELL TRANSFER EXPERIMENTS.
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Cells from lymph nodes of rabbits injected repeatedly with bovine serum albumin were transferred subcutaneously to previously irradiated rabbits, and the recipients were immediately injected with bovine serum albumin. A good antibody response resulted. In a series of such animals killed on successive days, skin samples at sites of cell deposition were removed and examined by immunofluorescence and by light microscopy. In these tissues abundant plasmocytes were found to have multiplied and differentiated in a regular progression from immature, to medium, to mature plasmocytes. During the 6 days of the experiment the small plasmocytes accumulated until they reached 85 per cent of the total plasmocytic population. The mitotic index of the large and medium plasmocytes averaged 11 per cent, implying a generation time of 6.3 hours on the basis of a 1 hour mitotic time. This rate of growth is sufficiently rapid to account for all the plasmocytes on the 6th day as deriving from less than 1 per cent of the population initially transferred. This rate and the orderly progression in the evolution of the plasmocytic population, make it highly improbable that plasmocytes arise from transformation of lymphocytes, but rather indicate that they spring from specific precursors already present among the transferred cells. (+info)
FETAL RESPONSE TO ANTIGENIC STIMULUS. IV. REJECTION OF SKIN HOMOGRAFTS BY THE FETAL LAMB.
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The fetal lamb was found to reject orthotopic skin homografts applied at any time after the 77th day of gestation. Prior to this, grafts remained in place without stimulating any detectable immunologic response. Once the fetus achieves the ability to reject the graft, the process occurs with the same competence and rapidity as in the adult. Graft rejection in the fetal lamb is unaccompanied by formation of plasma cells or by the production of typical immunoglobulins, thus supporting the suggestion that circulating antibody does not play an obligatory role in the process. (+info)
STUDIES ON GASTRIN.
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These three papers present studies on gastrin. The first paper describes a method of biological assay using the rat. The second paper demonstrates that the highest concentration of gastrin-like activity occurs in the antral mucosa, with a clear gradient of concentration of activity down the gut. However, it is to be noted that the total amount of extractable activity is greatest in the duodenum, although the concentration there is less than in the antrum. No activity was detected in the pancreas. The third paper studies the contents of gastrin-like activity in patients with duodenal ulcer and demonstrates higher figures when stenosis is present. Patients with benign gastric ulcer and carcinomata showed results equal to or greater than in those with the average uncomplicated duodenal ulcer. It was noted that two patients with dilated antra both had very low total gastrin-like activity. There was no correlation between total activity and maximal histamine-stimulated output of acid. There was, however, a positive correlation between the insulin-stimulated acid secretion and the total gastrin-like activity in the cases of uncomplicated duodenal ulcers. The clinical studies are still tentative in view of the several variables present, but it seems likely that they will in due course clarify the role of gastrin in the ulcer problem. (+info)