29 research outputs found
Lambda and Antilambda polarization from deep inelastic muon scattering
We report results of the first measurements of Lambda and Antilambda
polarization produced in deep inelastic polarized muon scattering on the
nucleon. The results are consistent with an expected trend towards positive
polarization with increasing x_F. The polarizations of Lambda and Antilambda
appear to have opposite signs. A large negative polarization for Lambda at low
positive x_F is observed and is not explained by existing models.A possible
interpretation is presented.Comment: 9 pages, 2 figure
Morbillivirus Glycoprotein Expression Induces ER Stress, Alters Ca2+ Homeostasis and Results in the Release of Vasostatin
Although the pathology of Morbillivirus in the central nervous system (CNS) is well described, the molecular basis of neurodegenerative events still remains poorly understood. As a model to explore Morbillivirus-mediated CNS dysfunctions, we used canine distemper virus (CDV) that we inoculated into two different cell systems: a monkey cell line (Vero) and rat primary hippocampal neurons. Importantly, the recombinant CDV used in these studies not only efficiently infects both cell types but recapitulates the uncommon, non-cytolytic cell-to-cell spread mediated by virulent CDVs in brain of dogs. Here, we demonstrated that both CDV surface glycoproteins (F and H) markedly accumulated in the endoplasmic reticulum (ER). This accumulation triggered an ER stress, characterized by increased expression of the ER resident chaperon calnexin and the proapoptotic transcription factor CHOP/GADD 153. The expression of calreticulin (CRT), another ER resident chaperon critically involved in the response to misfolded proteins and in Ca2+ homeostasis, was also upregulated. Transient expression of recombinant CDV F and H surface glycoproteins in Vero cells and primary hippocampal neurons further confirmed a correlation between their accumulation in the ER, CRT upregulation, ER stress and disruption of ER Ca2+ homeostasis. Furthermore, CDV infection induced CRT fragmentation with re-localisation of a CRT amino-terminal fragment, also known as vasostatin, on the surface of infected and neighbouring non-infected cells. Altogether, these results suggest that ER stress, CRT fragmentation and re-localization on the cell surface may contribute to cytotoxic effects and ensuing cell dysfunctions triggered by Morbillivirus, a mechanism that might potentially be relevant for other neurotropic viruses
Inclusive single-particle distributions and transverse momenta of forward produced charged hadrons in mu p scattering at 470 GeV
Using data from the Fermilab fixed target experiment E665, general properties of forward produced charged hadrons in ÎŒp interactions at a primary muon energy of 470 GeV are investigated. The normalized inclusive single-particle distributions for Feynman-x D(xF) and for the transverse momentum D(pt2, xF) are measured as a function of W and Q2. The dependence of the average transverse momentum squared ăpt2ă on xF, W and Q2 is studied. The increasing contribution from diffractive production as Q2 decreases leads to a reduction of the average charged hadron multiplicities at low (positive) xF and an enhancement at large xF, for Q2 âČ 10 GeV2. It also reduces ăpt2ă for Q2 âČ 5 GeV2 and 0.4 âČ xF < 1.0. © Springer-Verlag 1997