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D Riley

Publications and source records attributed to D Riley.

At least 109 records · Page 6Linked to original sources

RNA-binding properties of a translational activator, the adenovirus L4 100-kilodalton protein.

The adenovirus L4 100-kDa nonstructural protein (100K protein) is required for efficient initiation of translation of viral late mRNA species during the late mRNA species during the late phase of infection (B. W. Hayes, G. C. Telling, M. M. Myat, J. F. Williams, and S. J. Flint, J. Virol. 64:2732-2742, 1990). The RNA-binding properties of this protein were analyzed in an immunoprecipitation assay with the 100K-specific monoclonal antibody 2100K-1 (C. L. Cepko and P. A. Sharp, Virology 129:137-154, 1983). Coprecipitation of the 100K protein and 3H-infected cell RNA was demonstrated. The RNA-binding activity of the 100K protein was inhibited by single-stranded DNA but not by double-stranded DNA, double-stranded RNA, or tRNA. Competition assays were used to investigate the specificity with which the 100K protein binds to RNA in vitro. Although the protein exhibited a strong preference for the ribohomopolymer poly(U) or poly(G), no specific binding to viral mRNA species could be detected; uninfected or adenovirus type 5-infected HeLa cell poly(A)-containing and poly(A)-lacking RNAs were all effective inhibitors of binding of the protein to viral late mRNA. Similar results were obtained when the binding of the 100K protein to a single, in vitro-synthesized L2 mRNA was assessed. The poly(U)-binding activity of the 100K protein was used to compare the RNA-binding properties of the 100K protein prepared from cells infected by adenovirus type 5 and the H5ts1 mutant (B. W. Hayes, G. C. Telling, M. M. Myat, J. F. Williams, and S. J. Flint, J. Virol. 64:2732-2742, 1990). A temperature-dependent decrease in H5ts1 100K protein binding was observed, correlating with the impaired translational function of this protein in vivo. By contrast, wild-type 100K protein RNA binding was unaffected by temperature. These data suggest that the 100K protein acts to increase the translational efficiency of viral late mRNA species by a mechanism that involves binding to RNA.

Adenoviruses, Human↗

Economic credentialing survey of university teaching hospitals.

Economic credentialing, the process of applying economic criteria to the determination of initial appointments or reappointments of physicians to hospital medical staffs, has become a major issue in hospital medical staff relations. Nearly all major academic health center hospitals have the ability to perform economic analyses of faculty/physician clinical practices, and more than one-third of their CEOs see nothing wrong with terminating or denying hospital privileges for excessive use of hospital resources. Sixty-eight percent of surveyed academic health center respondents currently develop and review physician practice profiles, but only 35 percent of these respondents include economic data.

Academic Medical Centers↗

Results of the Cancer Research Campaign Adjuvant Trial for Perioperative Cyclophosphamide and Long-Term Tamoxifen in Early Breast Cancer reported at the tenth year of follow-up. Cancer Research Campaign Breast Cancer Trials Group.

Over 2,000 patients with early breast cancer were recruited into a trial between 1980 and 1985. This trial was of a factorial 2 x 2 design to investigate the benefits of a short course of perioperative cyclophosphamide or tamoxifen 20 mg daily for 2 years. At the tenth year of follow-up no significant benefit is noted for perioperative cyclophosphamide, however the main effect analysis for adjuvant tamoxifen demonstrates a significant improvement in disease-free survival which increases with time during the follow-up period. These results are in keeping with the World Overview of Trials of Adjuvant Tamoxifen. However, this study is unique, having a large number of node negative patients and over 500 premenopausal women in a comparison of tamoxifen and control. The relative risk reductions for the node negative patients for disease-free survival are greater than for the node positive patients. This might suggest that the absolute benefit for adjuvant tamoxifen is similar in both groups of patients, bearing in mind the increased risk of relapse with the node positive patients. No trend for interaction emerges according to age or menopausal status suggesting an identical benefit for premenopausal women. Of particular interest is the development of contralateral breast cancer. The initial overall effect which emerged at the third year of follow-up ceases to be apparent. However, subgroup analysis according to menopausal status suggests a trend for interaction with a reduction in the risk of contralateral breast cancer in the postmenopausal women and an increase in the risk of contralateral breast cancer in premenopausal women. Plausible mechanisms exist to explain this difference in outcome and these data need to be checked against other large trials of adjuvant tamoxifen at a time when we are considering the chemoprophylaxis of breast cancer in high risk premenopausal women.

Breast Neoplasms↗