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71.
Barch Deanna M.; Cohen Jonathan D.; Servan-Schreiber David; Steingard Sandra; Steinhauer Stuart S.; van Kammen Daniel P. 《Canadian Metallurgical Quarterly》1996,105(4):592
Semantic priming in word pronunciation was examined at 5 stimulus onset asynchronies (SOAs) in 75 medicated and 25 unmedicated people with schizophrenia (SCZ) and in 10 depressed and 28 normal controls. At SOAs 相似文献
72.
D Elias H Prigozin N Polak M Rapoport AW Lohse IR Cohen 《Canadian Metallurgical Quarterly》1994,43(8):992-998
Administered at a suitably low dose, the toxin streptozotocin (STZ) can trigger an autoimmune process leading to destruction of the beta-cells of the pancreatic islets. In this study, we examined specific immunological reactions in mice before and during the development of STZ-induced autoimmune diabetes. We now report that the development of spontaneous autoantibodies to insulin can serve as a marker of susceptibility to a low dose of STZ. Susceptible male mice of the C57BL/KsJ strain manifested such anti-insulin antibodies, and resistant female mice did not. Administration of a low dose of STZ (five daily doses each of 30 mg/kg) induced transient hyperglycemia approximately 20-30 days later, which temporarily remitted but was followed by intractable diabetes approximately 2.5 months later. The diabetogenic process triggered by the low dose of STZ was associated with an increase in the level of anti-insulin antibodies bearing the Dana and Micha (DM) idiotype, later followed by the appearance of anti-idiotypic antibodies that peaked before the onset of diabetes. Antibodies and T-cells reactive to hsp60 (heat shock protein) were triggered by the low-dose STZ administration and persisted throughout the period that preceded clinical diabetes. T-cells reactive to the p277 peptide of hsp60 were also observed. Finally, active immunization to hsp60 caused transient hyperglycemia by itself and also aggravated the hyperglycemia induced by low-dose STZ. Thus, autoantibodies to insulin can indicate susceptibility to a toxic trigger of diabetes, and a low dose of a toxin can activate the insulin and hsp60 autoimmunity that has been detected previously in the spontaneous autoimmune diabetes of NOD strain mice. 相似文献
73.
JL Cohen J Cheirif DS Segar LD Gillam JS Gottdiener E Hausnerova DE Bruns 《Canadian Metallurgical Quarterly》1998,32(3):746-752
We investigated whether changes in iron metabolism and the transferrin receptor (TRF-R) expression were involved in the antileukaemic effects of arabinoside cytosine (ara-C). Treatment with 100 nM ara-C for 48h reduced thymidine uptake and increased the surface expression of the TRF-R on leukaemic blasts derived from 13/16 (81%) patients and on the HL-60 and U-937 cell lines. Whereas intracellular non-haem iron was strongly depleted 24 h after ara-C addition, TRF-R up-regulation and recovery of intracellular non-haem iron concentration occurred together after a longer exposure of the cultured cells to the drug. Since iron is an essential regulator of cell proliferation we have evaluated the effects of the combination between ara-C and the iron chelator desferioxamine (DSF) on the growth of HL-60 and U-937 cells. We found that desferioxamine strongly potentiated the effects of ara-C on leukaemic cell growth inhibition and apoptosis. This is the first report of a positive interaction between ara-C and an iron chelator in terms of antileukaemic effects. 相似文献
74.
PD Miles S Li M Hart O Romeo J Cheng A Cohen K Raafat AR Moossa JM Olefsky 《Canadian Metallurgical Quarterly》1998,101(1):202-211
The aim of this work was to identify which proteins in horse dander extracts are allergens and to characterise them. Two-dimensional PAGE showed that horse dander preparations are composed of up to 50 proteins, all having acidic isoelectric points in the pH range 3-4.5. Immunoblots of two-dimensional PAGE were used to compare the reactivity of the proteins with IgE from 23 allergic patients. Patient sera were divided into two main groups recognising either allergens of 18.5 kDa or proteins of 27-29 and 31 kDa. The proteins of 27-29 kDa and 31 kDa were all N-glycosylated and their glycan chains seem to play a role in the binding of IgE from allergic patients. The sugar composition of their carbohydrate moiety was determined and lectin-binding experiments indicated presence of terminal sialic acid linked alpha-(2-->6) to galactose, galactose linked beta-(1-->4) to N-acetylglucosamine, and possibly presence of sialic acid linked alpha-(2-->3) to galactose. The 27-29-kDa glycoproteins had heterogeneous isoelectric points, most probably due to different degrees of sialylation in their oligosaccharide chains. The two 18.5-kDa allergens exhibited slightly different isoelectric points and their N-terminal sequences were identical, showing that they most likely were isoforms of the same protein. Sequence analyses revealed that their N-terminal sequences are similar to proteins belonging to the lipocalin family. We named the two 18.5-kDa proteins Equ c 2.0101 and Equ c 2.0102, according to International Allergen Nomenclature recommendations [King, T. P., Hoffman, D., Lowenstein, H., Marsh, D. G., Platts-Mills, T. A. E. & Thomas, W. (1995) J. Allergy Clin. Immunol. 96, 5-14]. The N-terminal of the allergens of 27-29 kDa were blocked and their sequences were not determined. Their amino acid compositions were determined and comparison with acidic mammalian proteins in the Swiss-Prot database revealed high scores with lipocalin proteins. This suggests that the glycosylated horse dander allergens belong to the lipocalin family, like Equ c 2.0101 and Equ c 2.0102. 相似文献
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76.
Bleomycin-induced cleavage was examined in several nicked, gapped, or intact duplex DNA substrates, including a structure designed to mimic a proposed singly nicked intermediate in double-strand cleavage. This nicked structure appeared to correctly target the second cleavage event in the complementary strand, resulting in a blunt-ended double-strand break, similar to that induced directly by bleomycin alone in an intact duplex of the same sequence. A one-base-gapped structure was markedly less efficient in correctly targeting bleomycin attack in the complementary strand. The results are consistent with a model of bleomycin-induced double-strand cleavage in which the nick formed by the initial bleomycin attack serves to target secondary attack to a specific position in the complementary strand, resulting in a double-strand break with a defined geometry. 相似文献
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