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Biomedical subjects

L Tracy

Publications and source records attributed to L Tracy.

5 recordsLinked to original sources
PubMed1991

Early effects of lead on bone marrow cell responsiveness in mice challenged with Listeria monocytogenes.

Listeria monocytogenes challenge of lead-treated mice results in increased mortality. Since macrophage development constitutes the initial phase of the immune response to L. monocytogenes, bone marrow and spleens from Pb-treated mice that were infected with L. monocytogenes were analyzed for their ability to form colonies when exposed to the macrophage growth factor CSF-1. Serum colony-stimulating activity also was evaluated. Data obtained indicate the Pb exposure results in decreased responsiveness of bone marrow and spleen cells to CSF-1 while colony-stimulating activity in serum rises. This lack of bone marrow-derived macrophage development may contribute to the increased mortality observed with L. monocytogenes challenged. Pb-treated mice.

Animals↗
PubMed1989

Lead-induced alterations of in vitro bone marrow cell responses to colony stimulating factor-1.

Bone marrow cell responsiveness to hematopoietic growth factors is an integral part of immune responsiveness. Since host resistance is often dependent on bone marrow cell responsiveness and Pb alters host resistance, the influence of Pb on bone marrow cell responsiveness to the hematopoietic growth factor CSF-1 was evaluated. Cell number, soft agar colony formation, cell cycle analysis, as well as 3H-thymidine incorporation were utilized to determine if CSF-1 driven bone marrow-derived macrophage (BMDM) proliferation in vitro is altered in the presence of PbCl2. Data obtained indicate that Pb potentiates the ability of CSF-1 to stimulate thymidine incorporation by BMDM; however, colony formation is inhibited reversibly, and the absolute number of cells in culture is adversely affected by Pb. Propagation of BMDM appears to be more sensitive to Pb (100 nM) than other immune parameters. The decrease in bone marrow cell responsiveness to CSF-1 in the presence of Pb observed in this system may contribute to the decrease in host resistance observed in Pb-exposed animals.

Animals↗
PubMed1988

Effect of lead on macrophage function.

Lead (Pb) has been shown to alter various parameters of immune function such as host resistance and antibody formation. In addition, various heavy metals have been implicated as inducers of autoimmunity. In these experiments, macrophages, isolated from the peritoneal cavity of mice exposed to various doses of lead in vivo as well as cells exposed in vitro were tested for the following immunologic parameters: phagocytosis, antigen presentation, interleukin 1 production, and their ability to stimulate the autologous mixed lymphocyte reaction (AMLR). The results obtained indicate that Pb appears to alter the ability of macrophages to present antigen by enhancing the AMLR while having no effect on phagocytosis or IL-1 production. These data suggest that Pb may interfere with antigen-specific interactions between macrophages and T cells.

Animals↗
PubMed1987

Transference perspectives of story telling.

Every story teller tells his stories to an imagined reader who is his transference imago. The evident validity of this proposition in the psychoanalytic process is paralleled in the literary process. Disjunctures between process or form and content and the uses of active and passive voices in the grammatical sense reveal the workings of transference in the writer's attempts, through his narrative voice, to influence the imagined reader or imago. Clinical and literary examples are employed to demonstrate these issues.

Communication↗