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M R Alvarez

Publications and source records attributed to M R Alvarez.

5 recordsLinked to original sources
PubMed1976

Microfluorometry of nuclear acridine orange metachromasia in lymphocytes of thymus, spleen, and blood of AKR and random-bred mice.

Lymphocyte chromatin lability to acid hyrolysis was studied using acridine orange fluorescence metachromasia in a high-lymphocytic-leukemia-susceptibility strain (AKR) and random-bred mice (ICR). Comparisons were made of blood, thymus, and spleen lymphocytes between random-bred, "normal" AKR, and leukemic AKR animals. The leukemic mice were in the stages of the disease characterized by enlarged thymus and spleen but preceding massive elevation of blood lymphocytes. The ranges of the mean chromatin acid lability overlapped and were nearly identical in peripheral blood lymphocytes. However, thymic and splenic lymphocytes showed a marked rise in mean chromatic acid lability in the leukemic animals. The ranges of the mean values of this parameter were also found to be far greater in the lymphopoietic organs of normal AKR than in the random-bred mice. The data indicate that anatomically normal AKR animals of an age in which they are highly susceptible to spontaneous lymphocytic leukemia may contain a greater number of lymphoblasts in both the spleen and the thymus than do comparable random-bred mice. The implications of these findings are discussed in relation to strain differences and the concept of thymic origin of lymphocytic leukemia in mice.

Acridines↗
PubMed1975

Microfluorometric comparisons of heat-induced nuclear acridine orange metachromasia between normal cells and neoplastic cells from primary tumors of diverse origin.

Nuclear fluorescence metachromasia of heated fixed cells subsequently stained with acridine orange was compared in smears and isolated nuclei of various types of primary tumors and normal cells from the tissues that gave rise to the tumors. The ratios of fluorescence emission at 590 and 530 nm reflect the thermal stability of chromatin in situ. The results show that the mean thermal stability of the chromatin in neoplastic cells was lower than the stability of their normal counterparts in all cases. This was found in both spontaneous and chemically induced tumors as divergent in type as a dog vaginal tumor and murine lymphocytic leukemia. These data, together with our previous observations in other neoplastic systems, indicate that reduced chromatin thermal stability may be a general characteristic of cells that have undergone neoplastic transformation and is not confined to rapidly growing tumors. The present investigation identifies the sources of variability encountered in measuring fluorescence metachromasia in slide preparations, and methods of minimizing this variability for potential cytodiagnostic application are discussed.

Acridines↗