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M Tono

Publications and source records attributed to M Tono.

6 recordsLinked to original sources
PubMed1975

Studies of the erythron.

Radionuclide studies of the erythron are valuable to the physician in evaluating the clinical situation in a wide variety of hematologic disorders. A complete and accurate analysis of the life cycle of the red cell can be obtained with a full iron kinetic study, in conjunction with a DF32P red-cell survival study. However, a complete iron kinetic study is not always necessary. It may be abbreviated by deleting the in vitro phase of the iron kinetic procedure. The abbreviated iron kinetic study is also done in conjunction with a DF32P red-cell survival study. It can easily be performed by injecting 59Fe-labeled plasma and monitoring externally over the spleen, liver, and sacrum. Measurements of red-cell survival may be obtained with either 51Cr or DF32P. Although 51Cr provides a relatively uniform label of circulating red cells and is convenient to count in vitro, its highly variable elution rate precludes an accurate measurement of erythrocyte survival. The 51Cr method provides only a rough index of circulating red-cell half-times as a measure of red-cell survival. DF32P, HOWEVER, IS A PERMANENT LABEL OF CIRCULATING RED CELLS. It provides a direct measurement of erythrocyte survival and permits in vivo labeling of red cells simply by means of direct intravenous injection. Because it has an elution rate that is virtually zero after minimal elution on the day of injection, and because it is not reutilized, DF32P is unquestionably the best agent known for the determination of red-cell survival. In addition to these diagnostic data, the complete iron kinetic study can provide data on the deposition of iron in storage and the rate of iron storage exchange. It can also determine if erythropoiesis is quantitatively abnormal and if the abnormality is located in the bone marrow or in other organs such as the liver or spleen. Although the study of hematologic disorders is one of the most rapidly developing areas of medical research, techniques that are currently available can provide an understanding of the life cycle of the red cell and valuable data that can be applied directly to the clinical situation. When performed accurately, these studies provide a thorough analysis of the pathophysiology of the erythron and are valuable clinical tools that can be used successfully in the diagnosis and evaluation of a broad spectrum of hematological disorders.

Anemia↗
PubMed1975

Blood volume.

During the past decade the diagnostic use of blood volume determinations has declined as a result of the generation of largely inaccurate results and inappropriate normalization and interpretation. After historical development of more than 50 years, current methodology employs 125I-labeled human serum albumin and 51Cr-labeled red blood cells to determine plasma volume and red cell volume, respectively. Accurate blood volume determinations require (1) abandoning the use of the mean body hematocrit:venous hematocrit ratio and using simultaneous independent measurements of both volumes; (2) delaying multiple postinjection patient samples until complete mixing and equilibration are complete; (3) backextrapolation of plasma concentrations of 125I to account for albumin loss from the plasma, and, rarely, back-extrapolation of red cell concentrations to account for dilution by red cells transfused during the procedure; (4) normalization of volumes by adjusting patient weight to normal correspondence with lean tissue mass, whenever necessary. A rapid, routine method that fulfills these four requirements is presented. A number of surgical and medical conditions in which blood volume determinations are very useful in diagnosis and therapy are discussed. Recently developed techniques for blood volume measurements include neutron acativation analysis and fluorescent excitation analysis. Correct normalization of accurate blood volume measurements will provide a valuable service to the entire medical community.

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