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B. Vogelstein, E.R. Fearon, S.R. Hamilton, S.E. Kern, et al., “Genetic alterations during colorectal-tumor development,” The New England Journal of Medicine, 319,525-32, 1 September 1988. Bert Vogelstein (Molecular Genetics Laboratory, Johns Hopkins Oncology Center, Baltimore): “It is widely believed that cancer is the result of a series of genetic alterations. This paper is important because it lends substantial support to this belief with regard to one of the most common human tumor types. The data in the paper suggest that colorectal neoplasia results from the mutational activation of an oncogne coupled with the loss of several genes that normally suppress tumorigenesis. The proposed model for colorectal cancers may also apply to other tumors in which such studies are more difficult to perform. G.J. Dehmer, J.J. Pompa, E.K. van den Berg, E.J. Eichhorn, et al. “Reduction in the rate of early restenosis after coronary angioplasty by a diet supplemented with n-3 fatty acids,” The New England Journal of Medicine, 319, 733-40, 22 September 1988. Gregory J. Dehmer (C.V. Richardson Cardiac Catheterization Laboratory, University of North Carolina Hospitals, Chapel Hill): “One of the recognized limitations of coronary artery angioplasty is the recurrence of the blockage or stenosis (so-called restenosis) within six months in approximately 25% to 40% of all treated arteries. While certain clinical and procedural factors may be associaated with a higher incidence of restenosis, the response of vascular tissue to the injury induced by angioplasty also may be important. Internal damage to the blood vessel activates blood platelets. The platelets ahere to the area, forming a blood clot. Current speculation suggests that the subsequent organization of this blood clot, perhaps in conjunction with the growth of smooth muscle cells and the release of certain mitogens from the vessel wall, contributes to restenosis. “Although n-3 fatty acid therapy has shown an effect in our investigation, other studies have different results. There are four studies evaluating the use of fish oil for the prevention of restenosis after angioplasty: two show a favorable effect, while two others do not. Further studies clearly need to be done. There has been considerable interest in this work because of the postulated mechanisms that may cause restenosis. Our work provides a clinical model for understanding the response of vascular tissue to injury and the factors that can potentially modify this response. This may have wide-reaching applications to our understanding of vascular biology and the development and prevention of atherosclerosis. PHYSICS S. Witanachchi, H.S. Kwok, X.W. Wang, D.T. Shaw, “Deposition of superconducting Y-Ba-Cu-O films at 400 C without post-annealing,” Applied Physics Letters, 53, 234-6, 18 July 1988. Sarath Witanachchi (Institute on Superconductivity, State University of New York, Buffalo): “Most of the electronic and microwave applications of superconducting thin films require in situ growth techniques with low processing temperatures, to obtain smooth surfaces and minimum interfacial diffusion. In this paper, we described such a technique. “ In vacuum evaporation-deposition processes, the energy of the evaporated atoms and molecules that impinge on the substrate plays a major role in determining the crystallinity of the growing film. Increased adatom mobility by high-energy atoms may lead to low recrystallization temperatures. Excimer laser evaporation has been proved to be an excellent technique. By introducing a weak oxygen plasma in the evaporation zone, we have been able to grow as-deposited films at low substrate temperatures. This has been accomplished by the increased adatom mobility on the substrate caused by O2, collisions, In addition, the increased activation energy of O2, compared with O2, aided in the film oxidation process

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