Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression (open access)

Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions …
Date: June 29, 1998
Creator: Lochter, Andre; Navre, Marc; Werb, Zena & Bissell, Mina J
System: The UNT Digital Library
Sixth International Conference on Precipitation: Predictability of Rainfall at the Various Scales. Abstracts (open access)

Sixth International Conference on Precipitation: Predictability of Rainfall at the Various Scales. Abstracts

This volume contains abstracts of the papers presented at the Sixth International Conference on Precipitation: Predictability of Rainfall at the various scales, held at the Mauna Lani Bay and Bungalows, Hawaii, June 29 - July 1, 1998. The main goal of the conference was to bring together meteorologists, hydrologists, mathematicians, physicists, statisticians, and all others who are interested in fundamental principles governing the physical processes of precipitation. The results of the previous conferences have been published in issues of the Journal of Geophysical Research and Journal of Applied Meteorology. A similar format is planned for papers of this conference.
Date: June 29, 1998
Creator: unknown
System: The UNT Digital Library
Modeling of laser knife-edge and pinhole experiments (open access)

Modeling of laser knife-edge and pinhole experiments

We describe simulations of experiments involving laser illumination of a metallic knife edge in the Optical Sciences Laboratory (OSL) at LLNL, and pinhole closure in the Beamlet experiment at LLNL. The plasma evolution is modeled via LASNEX. In OSL, the calculated phases of a probe beam are found to exhibit the same behavior as in experiment but to be consistently larger. The motion of a given phase � contour tends to decelerate at high intensities. At fixed intensity, the speed decreases with atomic mass. We then calculate the plasmas associated with 4-leaf pinholes on the Beamlet transport spatial filter. We employ a new propagation code to follow a realistic input beam through the entire spatial filter, including the plasmas. The detailed behavior of the output wavefronts is obtained. We show how closure depends on the orientation and material of the pinhole blades. As observed in experiment, a diamond orientation is preferable to a square orientation, and tantalum performs better than stainless
Date: June 29, 1998
Creator: Auerbach, J M; Boley, C D; Estabrook, K G; Feit, M D & Rubenchik, A M
System: The UNT Digital Library
Search for high mass photon pairs in p{anti p} collisions at {radical}s = 1.8 TeV (open access)

Search for high mass photon pairs in p{anti p} collisions at {radical}s = 1.8 TeV

The authors present results of a search for diphoton resonances produced inclusively and in association with a vector boson using 100 pb{sup {minus}1} of p{anti p} collisions using the CDF detector. They set upper limits on the product of cross section times branching ratio for p{anti p} {r_arrow} {gamma}{gamma} {r_arrow} X and p{anti p} {r_arrow} {gamma}{gamma} {r_arrow} W/Z. Using a NLO prediction for associated production cross section of a Higgs with a vector boson (W or Z), they set an upper limit on the branching ratio for H {r_arrow} {gamma}{gamma}. They set a lower limit on the mass of a `bosophilic` Higgs boson (e.g. one which couples only to {gamma}, W, and Z bosons with Standard Model couplings) of 82 GeV/c{sup 2} at 95% C.L.
Date: June 29, 1998
Creator: Wilson, P. J.
System: The UNT Digital Library
Nuclear data requirements for fission reactor neutronics calculations. (open access)

Nuclear data requirements for fission reactor neutronics calculations.

The paper discusses current European nuclear data measurement and evaluation requirements for fission reactor technology applications and problems involved in meeting the requirements. Reference is made to the NEA High Priority Nuclear Data Request List and to the production of the new JEFF-3 library of evaluated nuclear data. There are requirements for both differential (or basic) nuclear data measurements and for different types of integral measurement critical facility measurements and isotopic sample irradiation measurements. Cross-section adjustment procedures are being used to take into account the simpler types of integral measurement, and to define accuracy needs for evaluated nuclear data.
Date: June 29, 1998
Creator: Finck, P.
System: The UNT Digital Library
Enhanced Electron Attachment to Highly-Excited States of Molecules: Implications for Plasma Processing Discharges (open access)

Enhanced Electron Attachment to Highly-Excited States of Molecules: Implications for Plasma Processing Discharges

Recent studies show that large negative ion densities exist in plasma processing discharges, including those of weakly electronegative gases such as SiH{sub 4} and CF{sub 4}. Also, there is strong evidence that the negative ions could be the precursors for particulate formation in processing discharges. Even though it is now well established that large concentrations of negative ions exist in processing discharges, and that they play a crucial role in such discharges, the source of such high negative ion densities has not been clarified. In particular, gases like SiH{sub 4} and CH{sub 4}, which are commonly used in processing discharges, attach electrons only weakly in their ground electronic states (see the references). Due to the lack of an alternative mechanism, the origin of large negative ion densities in such weakly electronegative gases has been frequently attributed to electron attachment to radicals (molecular fragments) or other byproducts produced in the discharge. This hypothesis had not been tested in direct electron attachment measurements.
Date: June 29, 1998
Creator: Datskos, P. G.; Ding, W.; McCorkle, D. L. & Pinnaduwage, L. A.
System: The UNT Digital Library
The supercritical pomeron in QCD. (open access)

The supercritical pomeron in QCD.

Deep-inelastic diffractive scaling violations have provided fundamental insight into the QCD pomeron, suggesting a single gluon inner structure rather than that of a perturbative two-gluon bound state. This talk outlines a derivation of a high-energy, transverse momentum cut-off, confining solution of QCD. The pomeron, in first approximation, is a single reggeized gluon plus a ''wee parton'' component that compensates for the color and particle properties of the gluon. This solution corresponds to a super-critical phase of Reggeon Field Theory.
Date: June 29, 1998
Creator: White, A. R.
System: The UNT Digital Library