A trans10-18:1 enriched fraction from beef fed a barley grain-based diet induces lipogenic gene expression and reduces viability of HepG2 cells.

Beef fat is a natural source of trans (t) fatty acids, and is typically enriched with either t10-18:1 or t11-18:1. Little is known about the bioactivity of individual t-18:1 isomers, and the present study compared the effects of t9-18:1, cis (c)9-18:1 and trans (t)-18:1 fractions isolated from beef fat enriched with either t10-18:1 (HT10) or t11-18:1 (HT11). All 18:1 isomers resulted in reduced human liver (HepG2) cell viability relative to control. Both c9-18:1 and HT11were the least toxic, t9-18:1had dose response increased toxicity, and HT10 had the greatest toxicity (P<0.05). Incorporation of t18:1 isomers was 1.8-2.5 fold greater in triacylglycerol (TG) than phospholipids (PL), whereas Δ9 desaturation products were selectively incorporated into PL. Culturing HepG2 cells with t9-18:1 and HT10 increased (P<0.05) the Δ9 desaturation index (c9-16:1/16:0) compared to other fatty acid treatments. HT10 and t9-18:1 also increased expression of lipogenic genes (FAS, SCD1, HMGCR and SREBP2) compared to control (P<0.05), whereas c9-18:1 and HT11 did not affect the expression of these genes. Our results suggest effects of HT11 and c9-18:1 were similar to BSA control, whereas HT10 and t-9 18:1 (i.e. the predominant trans fatty acid isomer found in partially hydrogenated vegetable oils) were more cytotoxic and led to greater expression of lipogenic genes

Semileptonic BcB_c Decay and Heavy Quark Spin Symmetry

Semileptonic decay of the $B_c$ meson is studied in the heavy quark limit. The six possible form factors for $B_c \rightarrow B_s (B^0),B_s^* (B^{*0})$ semileptonic decay are determined by two invariant functions. Only one of these functions contributes at zero recoil, where it is calculable to lowest order in an operator product expansion in terms of the meson decay constant $f_B$ and the $B_c$ wavefunction. A similar result is found for $B_c \rightarrow D^0,D^{*0}$ and for $B_c\rightarrow\eta_c,J/\psi$ semileptonic decay for a restricted kinematic region. Semileptonic $B_c$ decay provides a means for determining the KM mixing angle $|V_{ub}|$.Comment: (12 Pages, no figures

Matched-pair analysis of hematopoietic progenitor cell mobilization using G-CSF vs. cyclophosphamide, etoposide, and G-CSF: Enhanced CD34+ cell collections are not necessarily cost-effective

AbstractUsing matched-pair analysis, we compared two popular methods of stem cell mobilization in 24 advanced-stage breast cancer patients who underwent two consecutive mobilizing procedures as part of a tandem transplant protocol. For the first cycle, 10 microg/kg/day granulocyte colony-stimulating factor (G-CSF) was given and apheresis commenced on day 4 and continued for < or =5 days (median 3 days). One week after the first cycle of apheresis, 4000 mg/m2 cyclophosphamide, 400 mg/m2 etoposide, and 10 microg/kg G-CSF were administered for < or =16 days (cycle 2). Apheresis was initiated when the white blood cell (WBC) count exceeded 5000 cells/microL and continued for < or =5 days (median 3 days). Mean values of peripheral blood WBC (31,700+/-3200 vs. 30,700+/-3300/microL) were not significantly different between cycles 1 and 2. Mean number of mononuclear cells (MNC) collected per day was slightly greater with G-CSF mobilization than with the combination of chemotherapy and G-CSF (2.5+/-0.21x10(8) vs. 1.8+/-0.19x10(8) cells/kg). Mean daily CD34+ cell yield, however, was nearly six times higher (12.9+/-4.4 vs. 2.2+/-0.5x10(6)/kg; p = 0.01) with chemotherapy plus G-CSF. With G-CSF alone, 13% of aphereses reached the target dose of 5x10(6) CD34+ cells/kg in one collection vs. 57% with chemotherapy plus G-CSF. Transfusions of red blood cells or platelets were necessary in 18 of 24 patients in cycle 2. Three patients were hospitalized with fever for a median of 3 days after cycle 2. No patients received transfusions or required hospitalization during mobilization with G-CSF alone. Resource utilization (cost of drugs, aphereses, cryopreservation, transfusions, hospitalization) was calculated comparing the median number of collections to obtain a target CD34+ cell dose of 5x10(6) cells/kg: four using G-CSF vs. one using the combination in this data set. Resources for G-CSF mobilization cost $7326 vs.$8693 for the combination, even though more apheresis procedures were performed using G-CSF mobilization. The cost of chemotherapy administration, more doses of G-CSF, transfusions, and hospitalizations caused cyclophosphamide, etoposide, and G-CSF to be more expensive than G-CSF alone. A less toxic and less expensive treatment than cyclophosphamide, etoposide, and G-CSF is needed to be more cost-effective than G-CSF alone for peripheral blood progenitor cell mobilization.Biol Blood Marrow Transplant 1999;5(6):379-85

Electroweak Corrections in Technicolor Reconsidered

Radiative corrections to electroweak parameters in technicolor theories may be evaluated by one of two techniques: either one estimates spectral function integrals using scaled QCD data, or one uses naive dimensional analysis with a chiral Lagrangian. The former yields corrections to electroweak parameters proportional to the number of flavors and the number of colors, while the latter is proportional to the number of flavors squared and is independent of the number of colors. We attempt to resolve this apparent contradiction by showing that the spectrum of technicolor one obtains by scaling QCD data to high energies is unlikely to resemble that of an actual technicolor theory. The resonances are likely to be much lighter than naively supposed and the radiative corrections to electroweak parameters may by much larger. We also argue that much less is known about the spectrum and the radiative corrections in technicolor than was previously believed.Comment: 17 pages (which incl 3 figures), BUHEP-92-25 HUTP-92/A033, text uses harvmac, figures use picte

The Higgs Boson Width is Adjustable

We show that it is possible to construct models in which the width of the Higgs boson is arbitrary - either smaller or larger than a standard model Higgs boson of the same mass. There are no new fields into which the Higgs boson decays. Instead, the coupling of the Higgs boson to the gauge bosons is adjusted. We construct and analyze weakly--coupled models with arbitrary--width Higgs bosons to investigate the phenomenology one might find in a strongly interacting model. In any such model new physics must enter at a mass scale which decreases as the Higgs boson width is adjusted away from its standard model value. In particular, if the Higgs boson is wider than the standard model Higgs boson, then interesting new physics must appear in the isospin--two channel.Comment: 16 pages, uses harvmac for tex and pictex (optional) for the figures. BUHEP-94-10, HUTP-94/A01

Electrical and material properties of hydrothermally grown single crystal (111) UO2

The semiconductor and optical properties of UO2 are investigated. The very long drift carrier lifetimes, obtained from current-voltage I(V) and capacitance-voltage C(V) measurements, along with the well-defined optical properties provide little evidence of an abundance of material defects away from the surface region. Schottky barrier formation may be possible, but very much dependent on the choice of contact and surface stoichiometry and we find that Ohmic contacts are in fact favored. Depth resolved photoemission provided evidence of a chemical shift at the surface. Density functional theory, with the Heyd-Scuseria-Ernzerhof (HSE) functional, indicates a band gap of a 2.19 eV and an anti-ferromagnetic ground state. Ellipsometry measurements indicates at UO2 is relatively isotropic with a band gap of approximately 2.0 eV band gap, consistent with theoretical expectations

Analyticity, Crossing Symmetry and the Limits of Chiral Perturbation Theory

The chiral Lagrangian for Goldstone boson scattering is a power series expansion in numbers of derivatives. Each successive term is suppressed by powers of a scale, $\Lambda_\chi$, which must be less than of order $4\pi f/\sqrt{N}$ where $f$ is the Goldstone boson decay constant and $N$ is the number of flavors. The chiral expansion therefore breaks down at or below $4 \pi f/\sqrt{N}$. We argue that the breakdown of the chiral expansion is associated with the appearance of physical states other than Goldstone bosons. Because of crossing symmetry, some ``isospin'' channels will deviate from their low energy behavior well before they approach the scale at which their low energy amplitudes would violate unitarity. We argue that the estimates of ``oblique'' corrections from technicolor obtained by scaling from QCD are untrustworthy.Comment: harvmac, 18 pages (3 figures), HUTP-92/A025, BUHEP-92-18, new version fixes a TeX problem in little mod

Spinning Particles, Braid Groups and Solitons

We develop general techniques for computing the fundamental group of the configuration space of $n$ identical particles, possessing a generic internal structure, moving on a manifold $M$. This group generalizes the $n$-string braid group of $M$ which is the relevant object for structureless particles. In particular, we compute these generalized braid groups for particles with an internal spin degree of freedom on an arbitrary $M$. A study of their unitary representations allows us to determine the available spectrum of spin and statistics on $M$ in a certain class of quantum theories. One interesting result is that half-integral spin quantizations are obtained on certain manifolds having an obstruction to an ordinary spin structure. We also compare our results to corresponding ones for topological solitons in $O(d+1)$-invariant nonlinear sigma models in $(d+1)$-dimensions, generalizing recent studies in two spatial dimensions. Finally, we prove that there exists a general scalar quantum theory yielding half-integral spin for particles (or $O(d+1)$ solitons) on a closed, orientable manifold $M$ if and only if $M$ possesses a ${\rm spin}_c$ structure.Comment: harvmac, 34 pages, HUTP-93/A037; UICHEP-TH/93-18; BUHEP-93-2