Morphologische Phasenkontrast-kinematographische Studien zum Verhalten von Knochenmarkzellen in vitro

Abstract

The myeloblast is nearly of the same size as the lymphozyte and has the same nucleus cytoplasma ratio of 0.7 but differs from it in its morphology, its high frequency of multiplication, and by its kinetic behaviour. By phase contrast observation the transformation of the myeloblast into the promyelocyte has been seen several times. The myeloblast like the lymphocyte is able to move although at a much slower speed. By locomotion the myeloblast, and likewise the lymphocyte can move between blood and bone marrow. Of the granulocytopoietic series only the promyelocyte and the myelocyte with their nuclear cytoplasm relation of 0.3 are found in the bone marrow. The monoblast but is about twice its size, and moves less often. Apart from its transformation into promonocyte, monocyte and histiocyte, the monoblast may evalue in another way: it grows into a cell of doubled size with the same nucleus cytoplasm ratio 0.7 in whose cytoplasm are seen a lot of big granules. The cell may now be characterized as a tissue macrophage or mastcell. In consequence a frequently multiplying basophilic cell with a coarse nuclear structure and nucleoli, grows from a diameter of 6.5 to one of 13.0 mum without marked morphologic change apart from becoming alpha-NA-Esterase positive and acquiring big lysosomes. When this haemocytoblast is small (K 1/4 to K 1/2), it can be triggered into the granulocytopoietic series, when it is bigger (K 1/2 to K1) into the monocytopoietic series, or in the size K1 to K2 by erythropoietin into the erythropoietic series. If no triggering takes place, the cell degenerates after having granulated. The lymphopoietic system is not connected to this system of stem cells committed to the granulocytopoietic, the monocytopoietic and the erythropoietic series. Therefore we postulate a dual haematopoietic system. In acute leukemias the spread of size of cells and nuclei is wider and kinetically active stem cells are rarer. Only leukemic promyelocytes are in locomotion vividly, in contrast to the normal ones. In leukemic myeloblasts there are fewer mitoses than in normal ones, but in leukemic promyelocytes and monoblasts the mitotic frequency is not reduced.

Origin of the Early Megakaryopoietic Progenitor Cell and Further Polyploidization in the Thrombopoietic Cell Series. Phase-Contrast Observations of Human Bone Marrow

“…All hematopoietic progenitor cells are characterized in phase-contrast microscopy as having a small cytoplasmic rim around a bright nucleus and prominent nucleoli with a high nucleus/cytoplasm ratio [10,31). We observed 320 progenitor cells with the wide range of nuclear diameters of 5.0-14.5 ,</m [12] for 17 h. Differentiation to better recognizable precursor cells (promye locytes, promonocytes, erythroblasts) and characteristic kinetic behavior allows the distinction of the progenitor cells deter mined to the diverse hematopoietic series [6][7][8].…”

“…Extremely long mito chondria and sometimes birefringent lysosomes occur in the cytoplasm of these cells. Special peculiarities are short, cytoplasmic projections from the cell surface similar to these in megakaryocytes, which give rise to platelets [1,2,11 ] while proerythroblasts form larger blebs on their surface [6,10]. 5 of these 58 multinucleated cells -megakaryoblasts -grew in a similar fashion to other progenitor cells to the double size during 9-56 h of observation.…”

“…The cells were cultured on an au tologous plasma clot for up to 10 days. The behavior of the cells, such as locomotion, pinocytosis and phagocytosis, was observed and particular attention was paid to cell growth, differentiation and mitosis of single progenitor and precursor cells of the various blood cell types [6,8,10]. This article deals with the mitotic anomalies we observed in the human hematopoietic progenitor cell pool [11], leading to octoploid cells, which should be the progenitor cells of the throm bopoietic cell line [27,29] and with the fur ther polyploidization.…”

Klaudios Ptolemaios életműve, hatása, értelmezése

“…For trigonometry on the surface of the sphere Ptolemy uses a figure that we call a Menelaus configuration. It is depicted in Figure 1, where all the arcs AB, BE, and so on are segments of a great circle less than 90°, Ptolemy proves (following Menelaus)that It can be shown that the four basic formulas used in modern trigonometry for the solution of right spherical triangles are directly derivable from (1) and (2). Hence all problems soluble by means of the former can also be solved by the use of Menelaus configurations.…”

“…1 Since he wrote several major works after the Almagest, this evidence fits well with the statement of a scholiast attached to works of Ptolemy in several late manuscripts-that he flourished under Hadrian and lived until the regin of Marcus Aurelius (161-180). 2 The only other explicit date is that of the "Canobic Inscription": this is found in manuscripts of Ptolemy's astronomical works and purports to be a copy of an inscription dedicated by Ptolemy to the "Savior God" at Canopus, a town at the western mouth of the Nile, in the tenth year of Antoninus (A.F. 147-147).…”