Chronic stress influences the immune system through the thyroid axis

The aim of the present work was to analyze the effect of chronic stress on thyroid axis and its influence on the immune response. For this purpose a murine model of chronic stress was developed to evaluate and to correlate thyroid hormone levels with humoral alloimmune response. Results show a reduction in serum levels of thyroid hormones, specially a significant decrease in serum levels of tri-iodotyronine (T3) in stressed animals. On the other hand, alloimmunization was not able to induce an early increment in T3 and thyroxine (T4) levels as it was previously reported in normal animals. In addition, lower titers of alloantibodies were obtained in animals under stress conditions as compared to normal mice. The sustitutive T4 treatment in stressed animals increased significantly alloantibody production as well as the early increment in thyroid hormones after antigenic challenge. These findings suggest that chronic stress induces an alteration of the function of thyroid axis that alters the immune response. (C) 2000 Elsevier Science Inc.Fil: Cremaschi, Graciela Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Gorelik, Gabriela Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Klecha, Alicia Juana. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lysionek, Alexis E.. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Genaro, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentin

Facilitating practitioner response to educational research and dissemination: A social marketing approach

Research generated and disseminated in publication form by National Research Centers, sponsored by the federal Department of Education, is acknowledged to be under-utilized by educational practitioners. Systematic study of that problem has not been a priority for the Centers or the Department of Education. Guided by social marketing theory and an associated model of consumer information processing and advertising effectiveness, the study proposes that a vivid publication, defined by color, copy positioning, contrast and directionality, would stimulate greater practitioner exposure, selective and intensive attention behavior than a publication that did not contain those variables. A cross-sectional design was employed to test those hypotheses, using two different versions of a publication produced by the National Center on Adult Literacy and disseminated to a sample of adult literacy practitioners via direct-mail. Subsequent measures on the dependent variables were taken through a self-administered mail survey. The study found no support for differential exposure, selective and intensive attention as a function of publication design. The findings were attributed to potential limitations in the operationalization of independent variables selected to represent vividness and the questionable efficacy of direct-mail dissemination to facilitate exposure in competitive information environments that appeared characteristic of the sample. The study concluded that experimentation in the selection and operationalization of publication mechanical elements, subsequent evaluation of their effectiveness for generating exposure and attention and the use of an alternate dissemination strategy might prove beneficial in NCAL\u27s future attempts to effect consumption of the informational product contained in the publication. It further suggested that successfully addressing practitioner under-utilization of Center products may require, (a) staff experienced in publication design, (b) evaluation predicated on practitioner behavioral responses toward publications, (c) audience segmentation predicated on media exposure preferences and, (d) the evolution of dissemination strategies compatible with those preferences. With regard to federal initiatives, the study concluded that the Department of Education might evolve improved evaluation criteria to guide Center efforts and undertake the sponsorship of a National Center for the Study of Dissemination

Experimental evidence pointing to the bidirectional interaction between the immune system and the thyroid axis

Among the many examples of neuroendocrine-immune system interactions the relationship between the thyroid axis and the immune function has yet to be clearly established. Here we studied the influence of thyroid hormones on the course of an alloimmune response. Murine T3 and T4 levels were found to be increased a few days after the immunization of mice with allogeneic lymphoid cells. Besides in vivo treatment with T4 was shown to increase alloantibody titers during the early stages of alloimmunization and to enforce lymphoid proliferation in vitro in a mixed lymphocyte reaction. Conversely, lowering thyroid hormone seric levels by propylthiouracil treatment, negatively modulates the humoral and cellular alloimmune responses. The evidence here points to the existence of a bidirectional communication between both systems. The possibility that the antigenic challenge would increase the thyroid gland activity thus leading to a positive modulatory action upon the immune response is also discussed.Fil: Klecha, Alicia Juana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Genaro, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Lysionek, A. E.. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Caro, R. A.. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Coluccia, A. G.. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; ArgentinaFil: Cremaschi, Graciela Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Laboratorio de Radioisótopos; Argentin