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2.
J Clin Invest ; 47(8): 1731-41, Aug. 1968.
Artigo em Inglês | MedCarib | ID: med-12189

RESUMO

The amount of fetal hemoglobin (Hb F) in erythrocytes of patients with sickle cell anemia (Hb SS disease) was measured by two methods: (a) photometry of individual cells strained for Hb F by the Kleihauer-Betke technique; and (b) chemical assay of alkali-resistant hemoglobin in cells distributed according to specific gravity by ultracentrifugation. Irreversibly sickled cells (ISC), which could be identified directly during photometry and which were found to gather in high concentration at the bottom of ultracentrifuged cell columns, contained significantly less Hb F than non-ISC. Cell content of total Hb was constant regardless of cell size, shape, or ultracentrifugal behavior: thus absolute amounts of Hb F and S varied reciprocally from cell to cell. In experiments designed to estimate age, at formation, and rate of destruction of ISC, Hb SS blood was incubated with selenomethionine-75Se (which labels reticulocytes) of 51Cr (which labels erythrocytes at random) and reinfused. Sequential blood samples were separated by ultracentrifugation into fractions rich in reticulocytes, non-ISC, ans ISC; and chronological changes in the specific activity of each fraction were determined. Analogous information was obtained from radioautography of sequential blood samples after reinfusion of whole blood labeled with amino acids-3H: this technique permitted direct visual characterization of labeled erythrocytes as ISC of non-ISC, all of which had been reticulocytes at the time of reinfusion. The transformation of non-ISC into ISC, presumably a manifestation of membrane damage, proved to begin soon after cell release from the marrow; and ISC subsequently underwent rapid removal from the circulating blood. It is therefore apparent from these studies that, in Hb SS disease, relatively small reciprocal changes in the amounts of the two major hemoglobins carry predictive importance: (a) net synthesis of Hb F is least in erythroid cells destined to become ISC; and (b) these irreversibly deformed erythrocytes suffer preferential destruction. (AU)


Assuntos
Humanos , Criança , Adulto , Masculino , Feminino , Anemia Falciforme/sangue , Eritrócitos Anormais/metabolismo , Hemoglobinas Anormais/análise , Aminoácidos/metabolismo , Anemia Falciforme/etiologia , Isótopos do Cromo , Envelhecimento Eritrocítico , Metionina/metabolismo , Fotometria , Radioisótopos , Selênio , Trítio , Ultracentrifugação
3.
Clin Sci ; 19(2): 275-85, May 1960.
Artigo em Inglês | MedCarib | ID: med-14665

RESUMO

Total body water has been estimated with tritiated water in 24 malnourished infants under the age of 2 years: the changes during recovery have been followed. On admission, the mean total body water was 84.5 per cent. of body weight: after recovery, this value fell to 62.6 per cent. Measurements have also shown an absolute decrease in body solids compared with normal for age. It is possible by this method to estimate the extent of tissue depletion (SUMMARY)


Assuntos
Humanos , Lactente , Pré-Escolar , Masculino , Feminino , Água Corporal/análise , Transtornos Nutricionais/fisiopatologia , Trítio/urina
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