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Tenofovir disoproxil fumarate induces peripheral neuropathy and alters inflammation and mitochondrial biogenesis in the brains of mice.
Mounting evidence suggests that antiretroviral therapy (ART) drugs may contribute to the prevalence of HIV-associated neurological dysfunction. The HIV envelope glycoprotein (gp120) is neurotoxic and has been linked to alterations in mitochondrial function and increased inflammatory gene expression, which are common neuropathological findings in HIV+ cases on ART with neurological disorders. Tenofovir disproxil fumarate (TDF) has been shown to affect neurogenesis in brains of mice and mitochondria in neurons. In this study, we hypothesized that TDF contributes to neurotoxicity by modulating mitochondrial biogenesis and inflammatory pathways. TDF administered to wild-type (wt) and GFAP-gp120 transgenic (tg) mice caused peripheral neuropathy, as indicated by nerve conduction slowing and thermal hyperalgesia. Conversely TDF protected gp120-tg mice from cognitive dysfunction. In the brains of wt and gp120-tg mice, TDF decreased expression of mitochondrial transcription factor A (TFAM). However, double immunolabelling revealed that TFAM was reduced in neurons and increased in astroglia in the hippocampi of TDF-treated wt and gp120-tg mice. TDF also increased expression of GFAP and decreased expression of IBA1 in the wt and gp120-tg mice. TDF increased tumor necrosis factor (TNF) α in wt mice. However, TDF reduced interleukin (IL) 1β and TNFα mRNA in gp120-tg mouse brains. Primary human astroglia were exposed to increasing doses of TDF for 24 hours and then analyzed for mitochondrial alterations and inflammatory gene expression. In astroglia, TDF caused a dose-dependent increase in oxygen consumption rate, extracellular acidification rate and spare respiratory capacity, changes consistent with increased metabolism. TDF also reduced IL-1β-mediated increases in IL-1β and TNFα mRNA. These data demonstrate that TDF causes peripheral neuropathy in mice and alterations in inflammatory signaling and mitochondrial activity in the brain
Strong lensing constraints on the velocity dispersion and density profile of elliptical galaxies
We use the statistics of strong gravitational lensing from the CLASS survey
to impose constraints on the velocity dispersion and density profile of
elliptical galaxies. This approach differs from much recent work, where the
luminosity function, velocity dispersion and density profile were typically
{\it assumed} in order to constrain cosmological parameters. It is indeed
remarkable that observational cosmology has reached the point where we can
consider using cosmology to constrain astrophysics, rather than vice versa. We
use two different observables to obtain our constraints (total optical depth
and angular distributions of lensing events). In spite of the relatively poor
statistics and the uncertain identification of lenses in the survey, we obtain
interesting constraints on the velocity dispersion and density profiles of
elliptical galaxies. For example, assuming the SIS density profile and
marginalizing over other relevant parameters, we find 168 km/s < sigma_* < 200
km/s (68% CL), and 158 km/s < sigma_* < 220 km/s (95% CL). Furthermore, if we
instead assume a generalized NFW density profile and marginalize over other
parameters, the slope of the profile is constrained to be 1.50 < beta < 2.00
(95% CL). We also constrain the concentration parameter as a function of the
density profile slope in these models. These results are essentially
independent of the exact knowledge of cosmology. We briefly discuss the
possible impact on these constraints of allowing the galaxy luminosity function
to evolve with redshift, and also possible useful future directions for
exploration.Comment: Uses the final JVAS/CLASS sample, more careful choice of ellipticals,
added discussion of possible biases. Final results essentially unchanged.
Matches the MNRAS versio
El Mañana: Año III Número 501 - (26/08/30)
Synchronous, time-resolved DRIFTS/MS/XAS cycling studies of the vapor phase selective aerobic oxidation of crotyl alcohol over nanoparticulate palladium reveal surface oxide as the desired catalytically active phase, with dynamic, reaction-induced palladium redox processes controlling selective versus combustion pathways
Electric Dipole Moments in the MSSM at Large tan(beta)
Within the minimal supersymmetric standard model (MSSM), the large tan(beta)
regime can lead to important modifications in the pattern of CP-violating
sources contributing to low energy electric dipole moments (EDMs). In
particular, four-fermion CP-violating interactions induced by Higgs exchange
should be accounted for alongside the constituent EDMs of quarks and electrons.
To this end, we present a comprehensive analysis of three low energy EDM
observables - namely the EDMs of thallium, mercury and the neutron - at large
tan(beta), in terms of one- and two-loop contributions to the constituent EDMs
and four-fermion interactions. We concentrate on the constrained MSSM as well
as the MSSM with non-universal Higgs masses, and include the CP-violating
phases of mu and A. Our results indicate that the atomic EDMs receive
significant corrections from four-fermion operators, especially when Im(A) is
the only CP-violating source, whereas the neutron EDM remains relatively
insensitive to these effects. As a consequence, in a large portion of the
parameter space, one cannot infer a separate bound on the electron EDM via the
experimental constraint on the thallium EDM. Furthermore, we find that the
electron EDM can be greatly reduced due to the destructive interference of one-
and two-loop contributions with the latter being dominated by virtual staus.Comment: 39 pages, 17 figure
Triton calculations with and exchange three-nucleon forces
The Faddeev equations are solved in momentum space for the trinucleon bound
state with the new Tucson-Melbourne and exchange three-nucleon
potentials. The three-nucleon potentials are combined with a variety of
realistic two-nucleon potentials. The dependence of the triton binding energy
on the cut-off parameter in the three-nucleon potentials is studied
and found to be reduced compared to the case with pure exchange. The
exchange parts of the three-nucleon potential yield an overall repulsive
effect. When the recommended parameters are employed, the calculated triton
binding energy turns out to be very close to its experimental value.
Expectation values of various components of the three-nucleon potential are
given to illustrate their significance for binding.Comment: 17 pages Revtex 3.0, 4 figures. Accepted for publication in Phys.
Rev.
Proposed Lunar Measurements of -Process Radioisotopes to Distinguish Origin of Deep-sea 244Pu
244Pu has recently been discovered in deep-sea deposits spanning the past 10
Myr, a period that includes two 60Fe pulses from nearby supernovae. 244Pu is
among the heaviest -process products, and we consider whether it was created
in the supernovae, which is disfavored by nucleosynthesis simulations, or in an
earlier kilonova event that seeded 244Pu in the nearby interstellar medium that
was subsequently swept up by the supernova debris. We discuss how these
possibilities can be probed by measuring 244Pu and other -process
radioisotopes such as 129I and 182Hf, both in lunar regolith samples returned
to Earth by missions such as Chang'e and Artemis, and in deep-sea deposits.Comment: Extensive rewrite of v1 with added emphasis of lunar sample return
missions, including Artemis and Chang'e. 11 pages, 4 figures, 2 tabl
Brane-world Cosmologies with non-local bulk effects
It is very common to ignore the non-local bulk effects in the study of
brane-world cosmologies using the brane-world approach. However, we shall
illustrate through the use of three different scenarios, that the non-local
bulk-effect does indeed have significant impact on both the
initial and future behaviour of brane-world cosmologies.Comment: 17 pages, no figures, iopart.cls, submitted to CQ
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