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PubMed1975

The use of Herr four-and-a-half clearing fluid for the rapid microscopic examination of thick sections of normal and neoplastic tissues.

We have demonstrated that Herr's 4 1/2 clearing fluid, developed for use with plant tissues, can be successfully used for the microscopic examination of thick sections of normal and neoplastic mammalian tissues. Rat Novikoff hepatoma, rat liver, and human colon and skin samples were fixed in Bouin's, stained with iron hematoxylin, treated with Herr's 4 1/2 clearing fluid and examined by phase contrast microscopy. Tissue architecture and cytological detail were easily observed by focusing through tissue sections as thick as 70 mu. The method permits rapid microscopic examination of mammalian tissues and enables the investigator to detect readily morphological abnormalities within a tissue.

Animals↗
PubMed1975

Coagulocyte alterations in clotting hemolymph of Carausius morosus L.

1. The structural changes in the coagulocytes of Carausius morosus during hemolymph coagulation in vitro have been studied under the PCM and in the TEM. 2. In agreement with former PCM observations on Carausius morosus, the coagulocytes are the only hemocytes to induce coagulation of the plasma. Immediately or after a few seconds upon withdrawal of the hemolymph, their structural changes consist of a considerable enlargement of the perinuclear cysterna and of direct ejection into the plasma of nuclear and cytoplasmic substances through microruptures of the cytoplasmic membrane. The other categories of hemocytes do not contribute to the plasma coagulation. Their structural alterations take place without breakage of the cytoplasmic membrane when the plasma reactions are already established. 4. These plasma reactions appear in the form of circular islands of granular material around the coagulocytes, of extension of the coagulum in the channels between the islands and of transformation of the clot into a network of threads. 5. As reported in other studies in the TEM, no specific organelle characteristic of the coagulocyte ultrastructure could be found in the coagulocytes of Carausius. 6. Owing to the absence of any specific structural criterion of identification, the results suggest that the functional difference between coagulocytes and the other categories of hemocytes as regards coagulation of the plasma might be caused in part by differences of permeability of the cell membranes.

Animals↗
PubMed1976

Aggregation of platelets and inert particles induced by thrombin.

Thrombin-induced platelet aggregation and release were investigated in washed platelet suspensions and in suspensions of inert particles in order to evaluate the role of fibrinogen-fibrin transformation in aggregometer tracings. Thrombin (0.25-2.0 U/ml) produced two waves of light transmission increase (LTI) in both platelet and inert particle suspensions containing fibrinogen, and concomittantly aggregates were observed under phase microscopy. Without fibrinogen, thrombin induced rapid release of platelet ADP but failed to cause second wave of LTI. The kinetics of LTI in platelet and inert particle systems were related to both thrombin and fibrinogen concentrations. A rapid second wave of LTI could be produced by direct interaction of thrombin-treated platelets or inert particles with polymerizing fibrin, and was inhibited by sodium sulfite and low pH of 5.1 which prevent fibrin monomer polymerization. No fibrin strands were noted in platelet aggregates fixed at the completion of the second wave of LTI. Apyrase and PGE1 inhibited the rate of first but not that of second wave LTI. The results suggest that the release of platelet ADP induced by thrombin primarily affects the first phase aggregation, and the second phase may result from interaction of thrombin-exposed platelets and polymerizing fibrin. Thus, the blood coagulation mechanism may be directly involved in platelet aggregation.

Adenosine Diphosphate↗
PubMed1975

Morphologic and functional characteristics of bone marrow macrophages from imferon-treated mice.

The iron storage macrophage has been isolated from the marrow of Imferon-treated mice and studied in vitro by morphologic, histochemical, and functional tests and isotope labeling techniques. These macrophages on stained preparations are large, many times binucleate cells (up to 150 mu), and show Prussian blue reactivity. In Epon-embedded, stained thick sections they contain elongated narrow basophilic inclusions. These macrophages are actively phagocytic and pinocytic; histochemical studies show that these cells are rich in acid phosphatase, nonspecific esterase, and PAS diastase-resistant activity. Iron storage macrophages do not incorporate the 3H-thymidine. The electron microscopic appearance of this macrophage shows that the cell has ferritin free in the cytoplasm and several types of cytoplasmic granules: those with large quantities of electron-dense ferritin and/or hemosiderin (type A), elongated granules (type B) with moderately electron dense homogeneous matrix and some ferritin at the periphery, and granules with heterogeneous content (type C). The above findings demonstrate that the iron storage cell is a mature macrophage which contains hydrolases, ferritin, and a unique population of cytoplasmic granules which are lysosomal in nature. There is some evidence to suggest that the unusual lysosome (type B granule) occurs after macrophages have ingested erythrocytes.

Acid Phosphatase↗
PubMed1975

Recognition by pregnancy serums of non-HL-A alloantigens selectively expressed on B lymphocytes.

A group of alloantibodies are found in pregnancy sera which react with antigens present on B lymphocytes and monocytes but are not detectable on the vast majority of unstimulated T cells. This specificity distinguishes them from HL-A antibodies which react with both cell types. They were readily recognized through indirect fluorescent antibody analysis by employing the combination of B-cell lymphoid lines and normal peripheral blood T cells. Different sera gave a variety of patterns of reactivity with a panel of 11 lymphoid lines. Similar differential patterns were also observed with normal B cells from different individuals particularly after concentrating the B cells. The antibodies were also cytotoxic to B cells and this procedure gave parallel results to the fluorescence method. The pattern of reactions obtained indicated a very heterogeneous system similar to that for HL-A. Special study of certain of the sera provided evidence that the lymphocyte-defined determinants of the mixed lymphocyte reaction system were involved. For convenience the term HL-B has been employed for these antigens.

Antibody Specificity↗
PubMed1975

[Demonstration of immunoglobulin determinants on lymphocyte surfaces by membrane immunofluorescence].

Isolated lymphocytes from peripheral blood of 22 healthy donors were examined with the help of the indirect membrane immunofluorescence (MIF) for immunoglobulin determinants on the surface of the cells. The quantity of MIF+-cells for IgM was on the average 8.7% (3-18) and for IgG 15.5%(8-18). Five different anti-IgM-sera were characterised with regard to their use in the MIF (precipitation titre, entire protein content, content of anti-IgM-antibodies). Differences in the quantity of the MIF+-lymphocytes were above all based on differing antibody concentrations of the sera. It was referred to further possible causes for these differences. The influence on the results of the examinations by protein addition and trypsination.

Adult↗
PubMed1975

[Cytotoxic effects of a leukocidin from Staphylococcus aureus (author's transl)].

In an attempt to improve the assay of leukocidin from Staphylococcus aureus a combined vital fluorochrome staining procedure with acridine organe and ethidium bromide was developed. It proved to be more suitable for the demonstration of leukocidic effects on leukocytes than phasecontrastmicroscopy. Damaged leukocytes fluoresced distinctly red and undamaged leukocytes green. With the fluorochrome-method leukocidic changes became also evident in some lymphocytes. These were not clearly demonstrated by phasecontrastmicroscopy.

Acridines↗
PubMed1977

[Morphological diagnosis of Pneumocystis carinii].

Pneumocystis carinii pneumonia can only be diagnosed once the microorganism is demonstrated. The authors review and illustrate various staining technics, and discuss for each of them specific advantages. All samples must by systematically examined both by phase contrast microscopy and by light microscopy after Gomori-Grocott and Gram-Weigert stains. This morphological study is completed by ultrastructural photographs.

Humans↗
PubMed1976

Cell separation using fluorescence emission anisotropy.

The emission anisotropy of selected fluorescent probes which interact with cells and their membranes is a sensitive parameter for studying the structural changes associated with different functional states. Such measurements can now be made on individual living cells at rates of up to 103 per second and the cells separated on the basis of the anisotropy function alone or combined with other physical signals using a multiparameter automated computer-controlled cell separator (MACCS). Thus, selection can be on the basis of simple or complex algorithms reflecting the size, macromolecular content, and rotational mobility of cellular components or liganded reporter molecules. Cells isolated in this manner are sterile, viable, and can be used for outgrowth or biochemical studies related to dynamic changes occurring during differentiation or malignant transformation.

Animals↗
PubMed1977

[Fluorescence microscopy demonstration of mitochondria in tissue culture cells using berberine].

The possibility of fluorescence microscopical examination of mitochondria in living animal cells using fluorochrome berberine sulphate is shown. At concentrations of 30--50 g per ml the chemical is accumulated selectively in mitochondria of living cells. The specificity of berberine sulphate accumulation in mitochondria was shown by comparative phase contrast and fluorescence microscopy. The advantages of the method is its high sensitivity and simplicity, especially when mitochondria can not be examined by the phase contrast microscopy.

Animals↗