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Apresenta organização e classificação dos sistemas de informação e cultura revistas a partir de O Nome da rosa, livro e filme. Destaca a representação como abordagem conceitual. Amplia a noção de linguagem estabelecida para o Sistema de Recuperação da Informação (SRI) e propõe a identificação de várias linguagens como constituintes dos sistemas de informação e cultura. Essas linguagens, tomadas como instrumentos conceituais e operacionais, são utilizadas para a análise da obra em questão.

T cells mediating chronic rejection (CR) of human kidney allografts were characterized by comparing them with those mediating acute rejection (AR). Two lines of analysis were performed using biopsy specimens (23 CR and 8 AR). First, the extent of infiltration of CD4+ and CD8+ T cells into allografts was assessed from mRNA expression of CD4 and CD8. The group of CR specimens was not significantly different from the group of AR specimens in terms of the extent of CD4+ and CD8+ T cell infiltration, underlining the importance of the immunological contribution to the progress of CR. Second, Th1/Th2 polarization in infiltrating T cells was investigated by measuring mRNA expression of interferon gamma (IFN-γ; a Th1 cytokine) and interleukin 4 (IL-4; a Th2 cytokine). IFN-γ expression was detected in most CR specimens, and was not significantly different between the group of CR specimens and the group of AR specimens. On the other hand, IL-4 expression was detected in only two CR specimens and one AR specimen; from its pathological features, the AR in this last case was concomitant with CR. These results suggest that most cases of CR and of AR are mediated by Th1 mechanisms, although some cases of CR show features of both Th1 and Th2. [ABSTRACT FROM AUTHOR]

We examined whether immunotherapy for recurrent spontaneous abortion (RSA) using paternal lymphocytes induces anti-T-cell receptor (TCR) idiotypic antibodies in RSA patients. The sera of these patients were assessed for inhibitory activity against mixed lymphocyte reactions (MLR) between maternal responder cells and paternal stimulator cells. Sera of four of the five women who maintained pregnancy successfully after immunotherapy showed significant MLR inhibition, whereas none of the five women who had unsuccessful pregnancies showed significant MLR inhibition. These sera inhibited the MLR of autologous responder T-cells, when stimulated with lymphocytes having the same HLA-DR antigens as the patient's husband, but not when stimulated with lymphocytes having unrelated HLA-DR antigens. This MLR inhibitory activity was absorbed by autologous maternal T-lymphoblasts induced by stimulation with lymphocytes having the paternal HLA-DR type but not by those induced by stimulation with lymphocytes having other HLA-DR types. The maternal serum inhibited the proliferation of autologous T-cells, but not of non-autologous T-cells, stimulated with paternal lymphocytes. These results indicate that anti-TCR idiotypic antibodies were induced in RSA patients by immunotherapy. These antibodies may contribute to maintaining pregnancy by negatively regulating maternal T-cells directed against HLA-DR antigens of the fetus. [ABSTRACT FROM PUBLISHER]

In order to analyse the diversity of T-cell receptors (TCRs) expressed by the T-cell population activated by allogeneic HLA-DR stimulation, TCRβ cDNA was synthesized from mRNA of human CD4+ T cells that had been stimulated in a primary mixed lymphocyte reaction (MLR). The TCRβ cDNA was amplified by the polymerase chain reaction (PCR), subjected to bacterial cloning, and sequenced from Vβ through Jβ. Twenty-six different Vβ genes and 10 different Jβ segments were detected among 56 randomly selected cDNA clones. Occurrences of Vβ317.1 and Jβ1.5 were higher than those found in the CD4+ T-cell population activated with a CD3-specific antibody. A total of 53 different CDR3 sequences, two of them occurring more than once, were detected among the 56 cDNA clones. In order to estimate the degree of CDR3 diversity, amino acid similarity in the CDR3 region of the cDNA was calculated and compared with those of the anti-CD3-activated T-cell sequences as well as those of various published T-cell clone sequences, each directed to either alloantigens or single antigenic peptides. It was found that the similarity score among CDR3 sequences obtained from the MLR (56.4 ± 10.3) was comparable to those of anti-CD3-activated T cells (55.7 ± 10.7) and those of T-cell clones directed toward alloantigens (range, 48.4 ± 12.4-59.4 ± 13.1), but significantly smaller than those of T-cell clones directed toward single antigenic peptides such as those derived from myelin basic protein (75.6 ± 17.9) and cytochrome c (76.9 it 20.5). These results provide quantitative proof that TCRs of T cells activated by primary allogeneic HLA-DR stimulation have a larger diversity than those recognizing single antigenic peptides. [ABSTRACT FROM AUTHOR]