Evaluation of in vivo breast fine needle aspirates by flow cytometry: an efficacy study.

BACKGROUND: Malignancy of the breast is frequently diagnosed through fine needle aspiration. In the hands of a skilled aspirator and cytopathologist, this can be a highly accurate procedure. PURPOSE: This study was undertaken to evaluate whether sufficient residual cells in the bore of the needle could be harvested and analyzed efficiently by flow cytometry analysis. The goal was then to determine the value of routine flow cytometry as an adjunctive technology in the interpretation of breast fine needle aspirations. METHODS: Cells were rinsed from the needles of 83 consecutive diagnostic fine needle aspirates after preliminary inspection had confirmed adequate material was obtained for cytopathology. Cells were washed, and nuclei prepared by detergent treatment. After ribonuclease treatment, DNA was stained with the fluorescent marker propidium iodide. DNA content per cell was determined by flow cytometry by measurement of right-angle fluorescence. RESULTS: Less than 4% of the samples were rejected for inadequate cell numbers. Flow cytometry criteria for evidence of malignancy included the presence of a DNA aneuploid population or an elevated rate of proliferation (13% or higher) of a diploid population. Accuracy of flow cytometry was based on cytopathologic interpretation in all cases except two which were based on results of excisional biopsy. The sensitivity of the flow cytometry analysis was 76%; the specificity was 100%, with results from flow cytometry pivotal in the correct diagnoses for two patients whose cytopathologic results were equivocal. Analysis of histograms indicated acceptable coefficients of variation for all populations. Gating analysis indicated the suitability of the material for this type of study, with an average of 85% of the events selected, or "gated in." Low recoveries were associated with the presence of necrotic debris in the sample. CONCLUSION: Flow cytometry can be a valuable adjunctive technology, capable of providing the cytopathologist with additional information regarding the character of cells analyzed.

Stimulatory effect of 3', 5'-adenosine monophosphate on protein synthesis in heat-shocked murine leukemia lymphoblasts.

The murine leukemia lymphoblast line L5178Y was tested for its early molecular response to the presence of dibutyryl cyclic AMP. Protein synthesis was reversibly inhibited by short durations of hyperthermia, and against this reduced background of protein synthetic activity, early leucine incorporation (30-120 min) was markedly and consistently stimulated by the presence of the cyclic nucleotide. The effect became one of inhibition with extended times of incubation (longer than 120 min).

Effect of dibutyryl cyclic adenosine 5'-monophosphate on protein synthesis in L5178Y cells after hyperthermia.

Protein synthesis in the L5178Y mouse lymphoma cell line was stimulated after short-duration heat shock by the addition of dibutyryl cyclic AMP. The stimulation was concentration-dependent (range, 0.01-1.0 mM) and was enhanced by preincubation of the cells in the presence of the cyclic nucleotide before the heat shock. Actinomycin, which blocks the recovery of protein synthesis activity after heat shock, did not block the cyclic AMP stimulation.

Thyroid hormones and protein synthesis in fetal mouse liver erythroid cells.

Hemoglobin synthesis represents an important step in the maturation of the developing erythron. In this study, we determined the effect of various thyroid hormones and analogs upon globin synthesis by fetal mouse liver erythroid cells. Globin synthesis was stimulated in 13--15 day fetal liver erythroid cells, whereas cells, whereas cells from 17 day fetuses were unresponsive. There was no correlation between stimulation of globin synthesis and reported calorigenic activity of the various hormones assayed.

Continuous or modulation expression of hematopoietic cell antigens in sublines of the leukemia cell line, K-562.

K-562 is described as a pluripotent leukemic cell line which expresses a diversity of hematopoietic cell differentiation antigens. With the use of monoclonal antibodies (MoAb), we show that the expression of these antigens is either "modulated", i.e. they are not expressed in early logarithmic growth but are expressed in late logarithmic growth, or "continuous", i.e. they are not affected by proliferation and phase of culture growth. Whether an antigen is modulated or continuously expressed appears to be an inherent property of the subline, since the expression of myeloid antigen binding the MoAb, PM81, was modulated on cells from a clone, whereas, the expression of this antigen was continuous by the parent subline and an independent subline F-1. Continuously expressed antigens appear to be an integral component of the K-562 cell surface matrix, while modulated antigen expression appears to be influenced by culture growth conditions.

Comparison of Clostridium difficile detection by monolayer and by inhibition of nucleoside uptake.

Detection and identification of Clostridium difficile toxin by traditional monolayer assay were compared with results obtained by a new procedure based on toxin-dependent inhibition of target cell uptake of a radioactive nucleoside. A high degree of correlation was noted between the two determinations. Although the new procedure was quantitative and objective, its value is seen at present as a rapid screen that may support results obtained in monolayers and as a potential assay for other, currently unidentified, toxins.

Vitamin B6 levels in patients with carpal tunnel syndrome.

Vitamin B6 levels were determined in patients with idiopathic carpal tunnel syndrome. Results from this limited study strongly suggest that vitamin B6 deficiency may accompany carpal tunnel syndrome. This study did not address the question of the causal relationship between vitamin B6 status and development of symptoms.

Effect of dibutyryl cyclic AMP on leucine incorporation in L5178Y cells. II. Effect of actinomycin and heat shock.

3H-leucine incorporation was assayed in L5178Y cells as a measure for protein synthesis. Protein synthesis was inhibited by short duration heat shock, actinomycin, cordycepin or a combination of these agents. Dibutyryl cyclic AMP had little or no effect upon protein synthesis in control cells. Dibutyryl cyclic AMP, however, stimulated protein synthesis in cells previously heat shocked and/or inhibited by actinomycin or cordycepin. The results have been interpreted to indicate that the cyclic nucleotide stimulated protein synthesis by influencing the metabolism of some species of RNA which may regulate translation.

Fetal hemoglobin: in vivo stimulation by D-thyroxine in adult marmosets.

Reactivation of fetal hemoglobin gene expressions was studied in new-world monkeys (marmosets). After a series of intraperitoneal injections of D-thyroxine, fetal hemoglobin production was increased in three experimental animals. Control animals were unaffected by the injection of the solvent. Because the percentage of cells containing fetal hemoglobin exceeded the total percentage of fetal hemoglobin, it was concluded that thyroid hormone influenced the synthesis of fetal hemoglobin rather than the development of a population of fetal cells.

Inhibitory effect of cyclic adenosine 2',3'-monophosphate on leucine incorporation by L5178Y cells.

The specificity of the reported stimulation of protein synthesis affected by dibutyryl adenosine cyclic 3',5'-monophosphate in L5178Y cells was tested by assaying the effect of adenosine cyclic 2',3'-monophosphate. Protein synthesis was assayed as total acid precipitable 3H-leucine. Leucine incorporation was inhibited by adenosine cyclic 2',3'-monophosphate. Alone, and in combination with actinomycin, 2',3'-cAMP inhibited leucine incorporation more rapidly and to a greater degree than did actinomycin alone. Since a similar potentiating effect was not observed with cordycepin, the hypothesis has been suggested that adenosine cyclic 2',3'-monophosphate inhibits protein synthesis by interfering with some post transcriptional event, perhaps modification of existing RNA. The results further suggest that 2,3 cyclic AMP may be antagonistic of the effects of 3,5 cyclic AMP, and as such may be useful as an inhibitor of that nucleotide's action.

Structure and synthesis of hemoglobin in marmosets (Saguinus fuscicollis).

Marmoset reticulocytes and bone marrow provide a valuable tissue resource for the study of primate hemoglobin structure and synthesis. The amino acid sequence of the marmoset hemoglobin has been determined, and the close homology between it and that of the human suggest it may be a valuable model for study of the effects of chemical modification on hemoglobin function. Hemoglobin synthesis by fetal bone marrow has been reported to be stimulated by physiologic levels of l-thyroxine. Differences in hormone responsiveness between fetal and adult red cell precursors have tentatively been ascribed to differences in permeability of the fetal and adult clones of cells.

Control of hemoglobin synthesis in fetal erythroid cells by L-thyroxine.

Fetal mouse liver cells were incubated in the presence of L-thyroxine, Globin synthesis by cells from the 13th to 15th days of gestation was stimulated by the presence of the hormone. Although protein synthesis by cells from the 17th day of gestation was stimulated, the protein was not identified as globin. A tentative conclusion was drawn that fetal erythroid tissue may be preferentially stimulated by thyroid hormone.

Flow cytometry of liver fine needle aspirates.

Fine needle aspiration analysis of intraabdominal masses is increasing in frequency. This study was designed to evaluate whether flow cytometry could be of value in the cytopathology interpretation of such specimens. Over a 4-year time span, 129 consecutive liver fine needle aspirates were evaluated by flow cytometry for DNA content, ploidy, and proliferation rate. Only excess cells remaining in the needle after cytology samples were prepared were included in this study. Overall sensitivity was 75% and specificity was 94%. In addition, flow cytometry results were pivotal for at least two specimens in achieving the appropriate diagnosis. For these reasons, it was concluded that flow cytometry could be a valuable adjunctive technology, to the cytopathologist in the interpretation of liver fine needle aspirates.