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71.
72.
An interactive CD-ROM program designed to reduce adolescent substance use was developed and evaluated. The program uses video vignettes to teach refusal skills and socially acceptable responses to substance use situations, specifically offers of marijuana. In a randomized pretest-to-posttest experiment with 74 public school students from six classes in three high schools, significant changes were observed at posttest on (1) the adolescent's personal efficacy to refuse the offer of marijuana, (2) the adolescent's intention to refuse marijuana if offered, and (3) the adolescent's perceptions of the social norms associated with substance use and the importance of respecting another's decision to refuse a drug offer. In addition, adolescents in the treatment condition were able to recall approximately 50% of the portrayed refusal strategies. Findings are discussed with regard to the potential benefits of an interactive multimedia approach for conducting substance use interventions. 相似文献
73.
Favorably tipping the balance between cytopathic and regulatory T cells to create transplantation tolerance 总被引:23,自引:0,他引:23
Therapeutic application of broadly reactive anti-T cell antibodies can lead not only to potent immunosuppression but also to profound and long-lived T cell depletion. We reasoned that a strategy that almost exclusively targets activated cytopathic donor reactive T cells and spares immunoregulatory networks might prove to be an exceptionally potent and highly selective means of producing long-term engraftment and tolerance. Herein we show that the combined administration of rapamycin and agonist IL-2- and antagonist IL-15-related cytolytic fusion proteins provides for long-term engraftment/tolerance in exceptionally stringent allotransplant models by (1) limiting the early expansion of activated T cells, (2) preserving and even exaggerating their subsequent apoptotic clearance, and (3) further amplifying the depletion of these activated T cells by antibody-dependent mechanisms, while (4) preserving CD4+CD25+ T cell-dependent immunoregulatory networks. 相似文献
74.
Turner CK Blieden TM Smith TJ Feldon SE Foster DC Sime PJ Phipps RP 《Journal of immunological methods》2004,291(1-2):63-70
The purpose of this study was to develop an enzyme-linked immunospot assay (ELISpot assay) that can be used with human adherent cells. While standard enzyme-linked immunosorbent assays (ELISAs) are available and widely used and ELISpot assays are used for nonadherent lymphocytes, no ELISpot assay has been developed for adherent cells. We used primary human fibroblasts from four different tissues (myometrium, lung, gingiva, and orbit), either unstimulated or interleukin (IL)-1beta-activated, to evaluate an ELISpot assay. Antibody pairs for IL-6 and IL-8 were used and results were compared to a standard ELISA. We found that we could reliably detect IL-6 and IL-8 spots with as few as 10 fibroblasts. Optimal cell numbers were 50 cells per well incubated for 8 h, although spots appeared as early as 2 h after incubation. Spots were absent when cells, primary, or secondary anti-cytokine antibodies were omitted from the protocol. Spot number and size can be ascertained using current automated ELISpot reader technology. The frequency of IL-6 and IL-8-producing human fibroblasts could also be determined. For example, 60% of the lung fibroblasts express IL-6, but IL-8 can be detected from only 40% of the cells. Approximately 80% of the human orbital fibroblasts make IL-6, whereas approximately 50% generate IL-8 following IL-1beta stimulation. These new findings show that fibroblasts from different human tissues display different frequencies of cytokine production and this further supports the concept of fibroblast diversity. The sensitivity of this new ELISpot assay is adequate for cytokine detection in just a few cells, unlike the standard ELISA. It should permit ascertaining the frequency of fibroblasts and other adherent cells that produce cytokines and, if desired, can be used in tandem with a standard ELISA to determine total cytokine produced. Moreover, the assay is suitable for normal human adherent cells that are often short-lived and difficult to cultivate. 相似文献
75.
Chronic schizophrenics from three different hospitals were compared to normal subjects on skin conductance parameters. In addition to “Responders” and “Nonresponders” as reported by Gruzelier and Venables (1972), a group of “Fast Habituator” schizophrenics was found. These subjects produce one or at most two responses before habituation in an orienting series. The SC waveform of fast habituator subjects shows long latency, slow risetime and long recovery, although the amplitude of response is within normal limits. 相似文献
76.
Martin Elhay Michelle Kelleher Antony Bacic Malcolm J. McConville Douglas L. Tolson Terry W. Pearson Emanuela Handman 《Molecular and biochemical parasitology》1990,40(2)
Lipophosphoglycan (LPG) of Leishmania is a polymorphic molecule comprising an alkylglycerol anchor, a conserved oligosaccharide core and a species-specific polymer of oligosaccharide repeats joined by phosphodiester bonds. This molecule, together with the membrane polypeptide gp63, has been implicated as a parasite receptor for host macrophages. To examine the role of LPG in parasite infectivity glycosylation variants of Leishmania major were generated by chemical mutagenesis of a virulent cloned line V121 and variants with modified LPG selected using the galactose-specific lectin Ricinus communis II (RCA II). Twenty RCA II-resistant primary clones were generated. Analysis of LPG profile by immunoblotting using LPG-specific monoclonal and polyclonal antibodies revealed that some of the clones were LPG-deficient. Three clones that did not bind any LPG-specific antibodies but expressed normal levels of the Mr 63 000 glycoprotein (gp63), a second parasite receptor for host, were chosen for detailed studies.All three clones expressed, at least to some extent, a surface molecule which could be labeled by mild periodate oxidation and sodium borotritide and behaved like LPG by hydrophobic interaction chromatography. All clones also bound a well-characterized monoclonal antibody L157 directed to the core oligosaccharide of LPG, but did not bind another monoclonal antibody, CA7AE, to an epitope on a repeating unit shared by Leishmania donovani and L. major LPG. A third monoclonal antibody, 5E6, recognizing LPG on the surface of wild-type V121 promastigotes bound only to RCA II-resistant clone 3A2-C3 and was restricted to an internal structure. The LPG molecule that this clone expressed was a form of LPG by its chromatographic behavior and by its monosaccharide and alkylglycerol composition. Clone 3A2-C3 was the only one to infect mice in vivo and survive in macrophages in vitro, albeit at a much reduced rate compared to wild-type V121 promastigotes. The data suggest that some form of LPG may be necessary to ensure parasite infectivity. 相似文献
77.
78.
Smith TJ 《Autoimmunity》2003,36(6-7):409-415
Graves' disease when fully expressed affects the thyroid gland and connective tissues of the orbit and pretibium. While the glandular disease is relatively well-characterized, the pathogenesis of the orbital and dermal components remains enigmatic. In the following article, we review some of the evidence suggesting that fibroblast activation in Graves' disease might play an integral role in the tissue remodeling associated with ophthalmopathy. The thyrotropin receptor (TSHR) is expressed at low levels in several connective tissue depots and by their derivative fibroblasts, including those from the orbit. Little direct evidence currently links extra-thyroidal TSHR expression with Graves' disease. Very recent observations now implicate the insulin-like growth factor-1 receptor (IGF-1R) as a fibroblast activating antigen. When immunoglobulins from patients with the disease, with or without clinical ophthalmopathy, bind IGF-1R on the surface of fibroblasts, the receptor becomes activated and upregulates the expression of two T lymphocyte chemoattractants, IL-16 and RANTES. Thus, IGF-1R may represent a second self-antigen with a pathogenic role in extra-thyroidal Graves' disease. 相似文献
79.
For both practical and methodological reasons, mice have been the most widely employed species for development of transgenic and gene knockin and knockout animals. However, basic behavioral and physiology control and regulatory mechanisms in mice are not well characterized. To broaden our understanding of the processes maintaining body fluid and blood pressure homeostasis in the mouse, the objectives of this study were to evaluate voluntary water, and sodium intakes during the development of renal hypertension and to examine the relationship between hypertension and the quantities of water and salt ingested. In male, C57BL/6J mice, two-kidney, one-clip renal hypertension (2K-1C) was induced, and water and 1.8% NaCl intakes were monitored for 2 weeks. At the end of this period, all animals received arterial catheters for direct recording of blood pressure. The mice that received renal artery clips were sorted into hypertensive (152+/-4 mm Hg) and normotensive (122+/-2 mm Hg) groups and were compared to control (117+/-4 mm Hg) animals that underwent a sham renal clipping procedure. Hypertensive 2K-1C animals had significantly elevated water intake compared to control animals. On most of the postsurgical days, the normotensive 2K-1C animals did not display increased water intake in comparison to the control group. No significant effect was detected for 1.8% saline intake between any of the pairs of groups. In summary, the reduction of blood flow to a single kidney in the 2K-1C model of renal hypertension induces high blood pressure accompanied by sustained hyperdipsia in the mouse. 相似文献
80.
J. Philip Kuebler Terry D. Oberley Lorraine F. Meisner Younan A. Sidky Catherine A. Reznikoff Ernest C. Borden Kenneth B. Cummings George T. Bryan 《Investigational new drugs》1987,5(1):21-29
Interferon-, interferon-, and interferon- differ in their antiproliferative effects for several cell lines. Interferons were thus assessed for their activity in inhibiting proliferation of three renal cell carcinoma cell lines. The malignant epithelial phenotype of each of these cell lines was confirmed by electron microscopy, histology, karyotype and tumorigenicity. When compared on an anti-viral unit basis, naturally produced interferon- was more effective than natural interferon- for all cell lines and clones. Proliferation of each of the cell lines was inhibited by interferon-. In all cases, removal of interferons from culture media resulted in resumption of the rate of cell growth after a variable delay of 6–10 days. If the antiproliferative effects of interferons predominate in mediating tumor regression, clinical response may depend upon the type of interferon to which the tumor is exposed. 相似文献