Lighting issues in the 1980's

Rubin, Arthur I.

doi:10.6028/nbs.sp.587

Cited by 13 publications

(21 citation statements)

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“…In order to determine whether type II interferon induces the synthesis of proteins similar to those induced by type I interferons, human fibroblast FS-4 cultures were labeled with [a5S]methionine either in the absence of interferon or in the presence of either type I (leukocyte or fibroblast) or type II interferon. Cell extracts were then prepared and analyzed as described (11,12). As reported earlier (11,12), treatment with human leukocyte or human fibroblast interferon induced the synthesis of five proteins, four of which could be detected by NaDodSO4/polyacrylamide gel electrophoresis of the whole extracts ( Fig.…”

Section: Methodsmentioning

confidence: 88%

See 1 more Smart Citation

Differential efficacies of human type I and type II interferons as antiviral and antiproliferative agents.

Rubin¹,

Gupta²

1980

Proc. Natl. Acad. Sci. U.S.A.

244

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Treatment of human fibroblast FS4 cultures with human type II interferon preparations induced the synthesis of at least four proteins that were similar in size to four of the five proteins induced by type I interferons (Mr 120,000, 88,000, 67,000, and 56,000). However, the M, 67,000 and 56,000 proteins were induced more strongly by type II than by type I interferon, and a counterpart of a Mr 80,000 protein induced by type I interferons was not noticeably induced by type II interferon preparations. We therefore compared type I and type II interferons for relative antiviral activities against different viruses (vesicular stomatitis, encephalomyocarditis, and vaccinia viruses and reovirus) and for cell growth-inhibitory activities on various cell types. The replication of vesicular stomatitis and encephalomyocarditis viruses was inhibited more strongly by type I interferon, whereas reovirus and vaccinia virus showed greater sensitivity to type II interferon preparations. This indicates that viruses may differ in their sensitivity to human type I and type II interferons and that the antiviral mechanisms induced by type I and type II interferons may have significant differences. The type I and type II interferons may also differ in their efficacies as antiproliferative agents. Type II interferon preparations at 2.5 units/ml inhibited the incorporation of [3H]thymidine to a greater extent than did type I interferon at 400 units/ml. (For both type I and type II interferons, the unit of interferon activity was defined as the concentration that decreased the yield of vesicular stomatitis virus by 50% in FS-4 cultures.) Furthermore, whereas type II interferon preparations had a reversible cytostatic effect on normal human fibroblasts at 10 units/ml, the transformed cells tested (HeLa, osteosarcoma, U-amnion) showed extensive cell death, thus indicating that it may have a cytocidal effect on certain tumor cells. It appears that human type II interferon (or a factor present in these preparations) may be a potent antitumor agent.Interferons are classified into two groups, called type I and type II interferons, which differ in their acid stability, their antigenic properties, and the nature of stimulus required for their production (reviewed in refs. 1 and 2). The human fibroblast and leukocyte interferons, so named because of their cellular origins, are both acid stable and are thus classified as type I interferons, although they are antigenically different. On the other hand, the interferon produced by human leukocytes in response to mitogenic or specific antigenic stimuli is acid labile and is classified as type II (or immune) interferon. This type II interferon activity is not neutralized by antisera raised against human fibroblast or leukocyte interferons and therefore appears to be distinct (3, 4).The antiviral action of type I interferons requires the expression of certain cellular genes because it is blocked by inhibitors of either transcription or translation (5-8) or by enucleation of cells (9, 10). Our stu...

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Section: Methodsmentioning

confidence: 88%

“…Procedures used for the labeling of cell cultures with [ 5S]-methionine in the presence or absence of interferon, preparation of their extracts, fractionation on poly(I)-poly(C)-agarose columns, and analysis by polyacrylamide gel electrophoresis in the presence of NaDodSO4 have been described (11,12) (see Fig. 1).…”

Section: Methodsmentioning

confidence: 99%

Differential efficacies of human type I and type II interferons as antiviral and antiproliferative agents.

Rubin¹,

Gupta²

1980

Proc. Natl. Acad. Sci. U.S.A.

244

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“…Inhibitors of transcription and translation block the induction of synthetase E (5)(6)(7)(8). The same is true of the IFN-induced eukaryotic initiation factor 2 protein kinase (5) and of [5][6][7][8][9][10] other proteins which can be detected by one-or two-dimensional polyacrylamide gel electrophoresis (9)(10)(11)(12)(13). Induction of these proteins by IFN therefore is likely to take place at the gene level.…”

mentioning

confidence: 99%

Interferon-dependent induction of mRNA for the major histocompatibility antigens in human fibroblasts and lymphoblastoid cells.

Fellous¹,

Nir²,

Wallach³

et al. 1982

Proc. Natl. Acad. Sci. U.S.A.

242

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In human cells treated with interferons, there is an increase in the amount of HLA-ABC and (32-microglobulin exposed on the cell surface. We have used a cloned HLA-A,B,C cDNA probe to demonstrate by molecular hybridization that this effect of interferon is preceded by a large increase in the amount of HLA mRNA in the cell. Thiseffect was found in five different human cell lines, with purified leukocyte and fibroblast interferons. The increase in HLA mRNA is comparable in its Idnetics and dose-response to the induction of (2'-5') oligo(A) synthetase mRNA by interferons. Therefore, interferons seem to activate at least two cellular genes which have different biochemical functions. Studies on the mechanism by which interferons (IFNs) inhibit virus multiplication have led to the discovery of several enzymes, inhibitors ofprotein biosynthesis, which are induced in cells exposed to IFNs (for review, see refs. 1-3). An assay for the mRNA of one of these enzymes, (2'-5') oligoadenylate synthetase (synthetase E), was developed and it was shown that IFNs induce, within a few hours, the accumulation of specific synthetase E mRNA in the cytoplasm of treated cells (4). Inhibitors of transcription and translation block the induction of synthetase E (5-8). The same is true of the IFN-induced eukaryotic initiation factor 2 protein kinase (5) and of 5-10 other proteins which can be detected by one-or two-dimensional polyacrylamide gel electrophoresis (9-13). Induction of these proteins by IFN therefore is likely to take place at the gene level.In addition to the above effects, IFNs also cause complex changes in the plasma membranes of cells (14). These changes alter the electric charge ofthe cells (15), decrease their motility (16), and influence cell-cell recognition events involved in the immune response (14,17). Biochemically, these membrane changes affect both the lipids (18) and several surface protein antigens (19,20). Thus, human IFNs increase the amounts of HLA-A,B,C antigens and of P2-microglobulin available for interaction with specific antibodies on the surface of human cells (21,22). These changes are specific because there is no increase in HLA-DR or in many other surface antigens. We wondered whether these membrane effects of IFNs were topical modifications in the exposure ofantigens on the cell surface or involved changes in gene expression similar to those found for synthetase E.To investigate this question we used a cloned HLA cDNA probe, pHLA-1 (23), to study the HLA-A,B,C mRNA levels in IFN-treated cells. Our results show that, in five human cell lines of lymphoblastoid and fibroblastic origins, both leukocyte IFN (IFN-a), and fibroblast IFN (IFN-,B) produce a large and rapid increase in HLA-A,B,C mRNA, which often precedes the increase in synthetase E mRNA. air. All cultures were grown at 37°C in the presence of 100 units of penicillin and 100 pg of streptomycin per ml. Human IFN-a was purified (31) from Sendai virus-infected chronic myelogenous leukemic cells, obtained from Institut Merieux (Lyon, F...

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“…Il est possible de préciser davantage les différences entre les situations de langage faisant partie de ce continuum à l'aide des sept vecteurs suivants mis en évidence par Rubin (1980) : la modalité de transmission du message (orale ou écrite); l'interaction entre l'émetteur et le récepteur; la participation de l'émetteur, c'est-à-dire son aptitude à tenir compte du récepteur; la proximité spatiale entre l'émetteur et le récepteur, dimension faisant référence au partage de l'environ-nement physique; la simultanéité, dans le temps, entre la situation décrite par l'émetteur et celle décodée par le récepteur (Celui-ci vit-il la situation en même temps que l'émetteur ou doit-il se mettre à la place de ce dernier pour l'interpréter? ); le degré d'abstraction du référent se mesurant en fonction de la pré-sence concrète de ce dernier; et, enfin, la distinction entre les interlocuteurs où l'on tient compte du partage des commentaires (association d'une déclaration à une personne ou à un personnage).…”

Section: Le Langage éCrit : Un Langage Décontextualiséunclassified

Les interactions lors de la lecture d’histoires en première année

Beaudoin

Giasson

Boisclair

1997

Nouveaux c@hiers de la recherche en éducation

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Réalisée auprès de dix enseignantes de première année et de quarante enfants fréquentant leur classe, la présente étude s’intéresse à la nature des interactions enseignante-élèves soulevées lors de la lecture d’une histoire. Celles-ci ont été classées selon leur niveau de décontextualisation. De cette manière, nous avons jugé pertinent de faire la distinction entre deux types de verbalisations : 1) les interactions décontextualisées accordant plus d’importance aux informations allant au-delà du texte et voulant être, par le fait même, cognitivement stimulantes, 2) les interactions contextualisées mettant l’accent sur l’information immédiatement disponible dans le texte ou sur l’illustration et faisant ainsi appel à des habiletés cognitives de niveau inférieur. Les résultats obtenus indiquent que les enseignantes recourent davantage à des interventions décontextualisées que contextualisées. De plus, le même phénomène a été observé chez leurs élèves qui, comme le prouvent nos analyses, ont tendance à imiter leur enseignante.This study, conducted with ten first-grade teachers and forty children in their classes, was concerned with the nature of teacher-pupil interaction elicited during story reading. These interactions were classified according to their degree of decontextualization. Thus we found it appropriate to distinguish between two kinds of verbalization: 1) non-context-bound interactions, assigning more importance to information beyond the text and aiming thereby to be cognitively stimulating; 2) context-bound interactions, emphasizing information immediately available from the text or the illustration and thereby calling upon lower-level cognitive abilities. The results obtained indicate that teachers tend to resort more to non-context-bound than context-bound interventions. Moreover, the same phenomenon was observed among their pupils who, as shown by our analyses, tend to imitate their teacher.Este estudio ha sido efectuado con diez profesores de primer grado y cuarenta niños que asisten a sus clases. El estudio trata sobre la naturaleza de la interacción profesoralumno surgida en la lectura de una historia. Esta interacción ha sido clasificada según su nivel de descontextualización; de esta manera, hemos creído pertinente hacer la distinción entre dos tipos de verbalización: 1) La interacción descontextualizada da más importancia a las informaciones que van más allá del texto y que pretenden ser, por el mismo hecho, cognitivamente estimulantes. 2) La interacción contextualizada hace énfasis sobre la información disponible inmediatamente en el texto o en las ilustraciones, recurriendo asi a las habilidades cognitivas de nivel inferior. Los resultados obtenidos indican que los docentes recurren más a intervenciones descontextualizadas que a aquellas en contexto. Además, el mismo fenómeno ha sido observado en sus alumnos quienes, tal como lo demuestran nuestros análisis, tienen tendencia a imitar a sus profesores.Die vorliegende Untersuchung wurde bei zehn Lehrerinnen der ersten Klasse und vierzig ihrer Sch...

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Lighting issues in the 1980's

Cited by 13 publications

References 0 publications

Differential efficacies of human type I and type II interferons as antiviral and antiproliferative agents.

Differential efficacies of human type I and type II interferons as antiviral and antiproliferative agents.

Interferon-dependent induction of mRNA for the major histocompatibility antigens in human fibroblasts and lymphoblastoid cells.

Les interactions lors de la lecture d’histoires en première année

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