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A A Steele

Publications and source records attributed to A A Steele.

7 recordsLinked to original sources

Arteriosclerosis.

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Arteriosclerosis

Pulmonary calcification: scanning electron microscopic and X-ray energy-dispersive analysis.

Nine patients with chronic renal failure or neoplastic involvement of bone showed metastatic calcification in their lungs at autopsy. On light microscopy, the calcifications were shaped like threads, beads, elongated rods, or tablets, whereas on scanning electron microscopy they were either amorphous or irregularly crystalline. Energy-dispersive x-ray analysis of the calcification showed the presence of calcium and phosphorus in all cases and traces of magnesium, sulfur, and other elements in some. The calcium-to-phosphorus ratio, obtained using Hall's formula, varied from 1.406 to 2.145, which is quite similar to that of normal bone and dystrophic calcification. Calcium phosphates, therefore, seem to be the principal mineral salts in all three types of calcification. In certain diagnostic and investigative problems, a correlative analysis of structure and chemistry at the ultrastructural level, both qualitatively and quantitatively in terms of their element ratios, can be done on tissue routinely prepared for light microscopy.

Adolescent

Adrenal hemorrhage in the adult.

Bilateral adrenal gland hemorrhage was found in 22 of 2,000 (1.1%) consecutive general hospital autopsies. Clinical features of these 22 patients with diffuse or focal bilateral adrenal hemorrhage have been analyzed and compared with previous series. In our experience, patients with this postmortem finding rarely manifest features of adrenocortical insufficiency and appear instead to die as a consequence of concomitant overwhelming illness, such as septicemia, body surface burns or cardiovascular catastrophe. Two-thirds of the current series had impaired renal function at the time of adrenal hemorrhage and three patients had pituitary gland necrosis. Experimental and clinical observations indicate that the "stressed" adrenal gland--under substantive endogenous or exogenous ACTH stimulation--is unusually susceptible to hemorrhage. While our own experience indicates that bilateral adrenal hemorrhage can infrequently be implicated as a factor contributing to patients' death, the possibility of adrenocortical insufficiency must be considered in patients at risk for adrenal hemorrhage. Such patients are those who are azotemic and have bacteremia, burns, or recent cardiovascular catastrophe, particularly when the latter is managed with anticoagulant administration. In these patients, unexplained clinical deterioration or the appearance of findings consistent with adrenocortical insufficiency mandate measurement of serum cortisol concentration and institution of stress-level corticosteroid replacement therapy until a diagnosis of acute adrenocortical insufficiency can be established or refuted.

Adrenal Cortex

Recovery of hematologic competence without engraftment following attempted bone marrow transplantation for aplastic anemia: Report of a case with diffusion chamber studies.

An 18-year-old male with severe aplastic anemia associated with hepatitis was prepared for bone marrow transplantation with cyclophosphamide (50 mg/kg/day) for 4 consecutive days. He then received 3.47 X 10(8) nucleated bone marrow cells per kilogram of body weight from his HL-A identical sister by intravenous infusion. Although subsequent karyotyping showed that engraftment was not achieved, prompt hematologic recovery ensued by the third week post-transplant. Diffusion chamber culture of the patient's bone marrow stroma, obtained prior to cyclophosphamide therapy, was carried out. A prompt increase in the number of cells in the chambers was observed. A differential cell count of the contents was similar to that seen when normal bone marrow is cultured in a similar manner.

Adolescent

Growth and differentiation of normal and leukemic human bone marrow cells cultured in diffusion chambers.

Bone marrow from healthy, normal volunteers and patients with acute myelocytic leukemia was cultured in diffusion chambers implanted into cyclophosphamide pretreated mice. Chambers were removed at regularly scheduled intervals over a period of 28 days. Total and differential cell counts were then done on the contents of each chamber. Normal human bone marrow showed an orderly pattern of growth and differentiation which was not found with leukemic bone marrow. Monocytes and macrophages were the predominant cell types in the diffusion chambers filled with normal marrow after day 10 of culture. Although leukemic specimens showed predominantly leukemic cells, a few mature polymorphonuclear leukocytes could be found throughout the entire culture period. Questions about the nature of the defect in acute myelocytic leukemia and the significance of the in vivo culture system are discussed. The results of these studies are compared and contrasted with studies of a similar type.

Animals