ETD Collection

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Now showing 1 - 5 of 5
  • Item
    A study of natural killer cells
    (1984) Herman, Marian Jean
    These studies involved the isolation of populations of peripheral blood leukocytes enriched for large granular lymphocytes (LGL), cells thought to be responsible for natural killer activity. It was found that the degree of cytotoxicity of LGLs could be modulated by various substances, namely, PLC/PRF/5 cell supernatants, interferon, certain monosaccharides and prostaglandin E2. This modulation appears to be due, at least in part, to the regulation of interleukin-1 (TL-) production by LGLs. LGLs are able to produce TL- in response, not only to LPS and Staphlococcus aureus hut also to a variety of NK sensitive target cells. The degree of sensitivity of these cells, to NK lysis, correlates with their ability to stimulate TL-1 production by LGLs„ The observed decrease in cytotoxic activity of LGLs from patients with advanced malignant disease can be ascribed to a defect in TL-1 production by these LGLs, an effect which can be partially corrected by in vitro interferon treatment. Treatment of target cells with IL-1 increased cytotoxicity of cancer patients LGLs to normal levels. This effect r v , appears to he a result, of increased hi ruling of LGLs to the target cells. It is postulated, therefore, that LGLs, coming into contact with K562 cells, produce II.-l which acts on the target cells enhancing their ability to bind further LGLs and thereby increasing the cytotoxicity of the latter.
  • Item
    Growth regulation by heparin in the vascular wall
    (1983-06-10) Karnovsky, Morris, John
    Vascular smooth muscle proliferation follows upon endothelial injury, and is thought to be an early component in the pathogenesis of atherosclerosis, and a possible noxious consequence of vascular surgery. We have shown that heparin suppresses vascular smooth muscle proliferation iri vivo and in vitro. The inhibitory effect is specific for heparin, and not other anions, and is not related to the antithrombin III binding activity of heparin. It is dependent on the size of the molecule, (hexasaccharidees or smaller being ineffective), and O-sulfation, but not N-sulfation
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    Investigation of the immune-modulatory effects of erythromycin
    (1986-06-20) Fernandes, Antonio, Celestino
    The Literature Review covers the immunosuppressive and immunopotentiating properties of antibiotics on the immune system and the effects these could have on the resolution of an infection. The possible pathogenic mechanisms of C. albicans are also reviewed in this section. The experimental section shows that pre-treatment of mice with erythromycin increases the mean survival time following intraperitoneal inoculation of C. albicans. It was shown that erythromycin enhanced lymphocyte transformation and PMNL migration in both in-vivo and in-vitro situations. These enhanced immunological components probably caused improved survival times in the aforementioned animal experiments. To investigate the effects of oral administration of erythromycin on in-vivo PMNL migration in adult volunteers a new quantitative test which could only be applied to humans was developed and is described in detail. Using this method preliminary data were obtained which show that erythromycin increases PMNL migration in-vivo.
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    The role of ferritin in iron absorption
    (1967-01) Torrance, J. D.
    Although reports of the medicinal use of iron date back to ancient times it was not until the present century that the many functions of iron in the body were studied. Once started, the investigation received impetus from the seriousness of iron deficiency anaemia, a major cause of ill health throughout the world. The introduction of radio-isotope tracer techniques in 1939 greatly facilitated investigation of absorption, excretion and the metabolic pathways of iron. The tremendous amount of work already carried out has led to a fairly comprehensive knowledge of the various aspects of iron metabolism. Nevertheless, there remain wide gaps in the overall picture. In
  • Item
    An in vivo and in vitro study of some luminal and cellular factors influencing iron absorption
    (1966-03) Jacobs, Peter
    Although the various factors which influence the absorption of iron from the gastrointestinal tract have been extensively investigated, there still remains uncertainty concerning several basic aspects of this process