ABSTRACT The seeding efficiency of colony‐forming cells from normal, regenerating and velocity‐sedimented cycling and non‐cycling narrow preparations was compared. Colony‐forming cells in cycle were found to exhibit a 50% reduction in splenic seeding when compared to normal marrow or sedimented non‐cycling cells. The results of this study indicate that the spleen colony assay underestimates the total number of colony‐forming cells by a fraction which is directly related to the number of cells in cycle.
Research Articles| March 17 2009 Mechanisms of Leukocyte Production and Release: IV. Factors Influencing Leukocyte Release from Isolated Perfused Femora of Rats with Chloroleukemia Subject Area: Hematology , Oncology Evelyn E. Varsa; Evelyn E. Varsa Department of Biology, Graduate School of Arts and Science, New York University, New York, N. Y Search for other works by this author on: This Site PubMed Google Scholar Joseph LoBue; Joseph LoBue Department of Biology, Graduate School of Arts and Science, New York University, New York, N. Y Search for other works by this author on: This Site PubMed Google Scholar Eugene S. Handler; Eugene S. Handler Department of Biology, Graduate School of Arts and Science, New York University, New York, N. Y Search for other works by this author on: This Site PubMed Google Scholar Burton S. Dornfest; Burton S. Dornfest Department of Biology, Graduate School of Arts and Science, New York University, New York, N. Y Search for other works by this author on: This Site PubMed Google Scholar Albert S. Gordon; Albert S. Gordon Department of Biology, Graduate School of Arts and Science, New York University, New York, N. Y Search for other works by this author on: This Site PubMed Google Scholar Francis C. Monette Francis C. Monette Department of Biology, Graduate School of Arts and Science, New York University, New York, N. Y Search for other works by this author on: This Site PubMed Google Scholar Acta Haematol (1965) 33 (5): 287–296. https://doi.org/10.1159/000209538 Article history Published Online: March 17 2009 Content Tools Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Evelyn E. Varsa, Joseph LoBue, Eugene S. Handler, Burton S. Dornfest, Albert S. Gordon, Francis C. Monette; Mechanisms of Leukocyte Production and Release: IV. Factors Influencing Leukocyte Release from Isolated Perfused Femora of Rats with Chloroleukemia. Acta Haematol 1 May 1965; 33 (5): 287–296. https://doi.org/10.1159/000209538 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsActa Haematologica Search Advanced Search This content is only available via PDF. 1965Copyright / Drug Dosage / DisclaimerCopyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements. Article PDF first page preview Close Modal You do not currently have access to this content.
The double‐labelling, two‐emulsion autoradiographic technique was used to study DNA synthesis time and related nuclear sub‐cycle durations of erythroid cell precursors in three week‐old rats. As employed in this short‐term investigation, the double‐labelling technique permitted direct estimates of DNA synthesis time to be made independently of labelling indices from the flow of two populations of labelled cells through the S‐phase of the nuclear cycle. The application of a second autoradiographic emulsion over single‐emulsion preparations made possible a more objective distinction between the two labels than can be done with single emulsion preparations. The following estimates were obtained from counts made on nine rats and a total of 45,000 cells: DNA synthesis time, 7.0 ± 0.5 hours; mitotic time (not including early prophase), 20 ± 3 minutes; average turnover time, 19.0 ± 1.8 hours.
Aortic blood from normal, sham-splenectomized, and splenectomized rats was incubated with tritiated thymidine (2 μc/ml) for 1 hour at 37°C and the labeling incidences for the buffy coat leukocytes determined autoradiographically. It was found that a small percentage of mononuclear cells in the peripheral blood of normal rats were capable of incorporating tritiated-thymidine. Following splenectomy the numbers of these cells increased more than 4-fold for 23 days post-operation. The labeled cell types are described and possible causes for their increase in numbers after splenectomy are discussed.
S ummary . Tritiated thymidine autoradiography was used to study the control of granulocyte production and release using the irradiated leg shielded mouse as an experimental model. Neutropenia resulted in a shortening of 24–36 hr in the mean transit time through the non‐proliferating granulocyte compartment. There was little difference between neutropenic and control animals in labelling indices of the cells in the proliferative granulocyte compartments, which suggests that the granulocytic hyperplasia observed in the neutropenic mice was predominantly due to differentiation of morphologically unrecognizable precursor cells rather than increased proliferation of morphologically recognizable cells. The persistence of a labelling index of approximately 60% in the myeloblast‐promyelocyte compartment 24 hr after injection suggests that these precursor cells were rapidly proliferating.
The technique of double‐label, double‐emulsion autoradiography was used to study the proliferative activity of bone marrow eosinophils in male rats of four age groups (weanlings, young adults, adults and aged adults). No alterations in the duration of the cell generative cycle (T c ), DNA synthetic period (T s ), or mitosis (T M ) were observed to accompany aging. Estimates of Ts were 10 1/2–11 hours; of T M , 0.33 hours; of generation time, 22–25 hours. Hourly production rates varied with age only when related to body weight, with estimates ranging from 10.2 ± 2.1 times 10 3 eosinophils/hour/mg. marrow/100 g. in the youngest rats to 1.6 ± 0.3 times 10 3 eosinophils/hour/mg./100 g. in the oldest rats. The data also suggested that approximately 2/3 of the marrow eosinophils were non‐dividing cells and that the maturation of eosinophil precursors in the rat is a highly complex process.
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