907,031 research outputs found
The expression and signalling patterns of CD180 toll like receptor in Chronic Lymphocytic Leukaemia (CLL)
Chronic lymphocytic leukaemia (CLL) is characterised by a progressive accumulation of mature CD5+CD20+CD23+ lymphocytes. Despite the remarkable progress in our understanding of the immunobiology of CLL, the aetiology of the disease remains unknown. The consensus is that CLL cells are driven by (auto)antigen(s) through the B cell receptor (BCR) and are regulated by a variety of signals received from the microenvironment, including toll-like receptors (TLR).Our group has previously shown that engagement of the CD180 orphan TLR expressed by approximately 60% of CLL cells, can re-wire the sIgM-mediated signalling from a pro-survival pathway, involving phosphatidylinositol-4,5-bisphosphate3-kinase (PI3K) and protein kinase B (AKT) to the potentially pro-apoptotic pathway through mitogen-activated protein kinase (p38MAPK).
However, little is known about the function of the other BCR - sIgD in CLL and its possible interaction with CD180. Here we studied intracellular signalling and apoptosis of CLL cells following sole or sequential ligation of CD180 and sIgD.
Our data indicated that following sequential ligation of CD180 and sIgD, CLL samples demonstrated enhanced p38MAPK phosphorylation leading to increased apoptosis of CLL cells indicating synergistic relationship between CD180 and sIgD. To better understand the prognostic importance of CD180 expression we sought to determine whether CD180 and other prognostic markers such as CD38 and ZAP70 displayed any correlation with the known cytogenetic aberrations:TP53 and DLEU1. Our results suggested that CLL cells with DLEU1 deletion are characterised by the negative expression of both, CD180 and CD38, and this might have a significance for CLL prognosis.
To explain this correlation, we hypothesised that interaction of CLL cells with their microenvironment through TLRs leads to the expansion of leukaemic clones, in vivo, in lymph nodes. Our results indicated that CD180 is heterogeneously expressed in the paraffin tissue sections of the lymph nodes of CLL patients and its expression positively correlates with the expression of Ki-67.
Our data demonstrated, that although CD180 expression and signaling might have negative prognostic importance in CLL due to the enhanced proliferation of leukaemic cells, its interaction with sIgD would re-direct leukaemic cells towards apoptosis thus opening new opportunities for the disease immunotherapy
Unregulated Desires: Anomie, the “Rainbow Underclass” and Second-generation Alevi Kurdish Gangs in London
This article offers a case study of the adaptation strategies of a section of second-generation young male Alevi Kurds in London and the social conditions which make some of them more prone to join gangs and to reject mainstream institutions in their search for instant material rewards. It is instructive to use Durkheim’s analysis of society’s integrative and regulative functions and particularly his concept of anomie to understand a situation where the legitimate means in the pursuit of material wealth and comfort are out of balance with the demand, calling into question the legitimacy of the institutions which provide these functions. Those who cannot compete through existing institutions are more likely to seek alternative means to achieve these ends. Durkheim identified youth as more vulnerable to such unregulated desires and I argue that his approach offers valuable insights into the anomic pressures confronting second-generation migrant young men in particular
Microscopic theory of absorption and emission in nanostructured solar cells: Beyond the generalized Planck formula
Absorption and emission in inorganic bipolar solar cells based on low
dimensional structures exhibiting the effects of quantum confinement is
investigated in the framework of a comprehensive microscopic theory of the
optical and electronic degrees of freedom of the photovoltaic system. In a
quantum-statistical treatment based on non-equilibrium Green's functions, the
optical transition rates are related to the conservation of electronic
currents, providing a quantum version of the balance equations describing the
operation of a photovoltaic device. The generalized Planck law used for the
determination of emission from an excited semiconductor in quasi-equilibrium is
replaced by an expression of extended validity, where no assumptions on the
distribution of electrons and photons are made. The theory is illustrated by
the numerical simulation of single quantum well diodes at the radiative limit.Comment: 6 pages, 5 figures, extended LaTeX version of the EUPVSEC09
proceedings articl
On the influence of the cosmological constant on gravitational lensing in small systems
The cosmological constant Lambda affects gravitational lensing phenomena. The
contribution of Lambda to the observable angular positions of multiple images
and to their amplification and time delay is here computed through a study in
the weak deflection limit of the equations of motion in the Schwarzschild-de
Sitter metric. Due to Lambda the unresolved images are slightly demagnified,
the radius of the Einstein ring decreases and the time delay increases. The
effect is however negligible for near lenses. In the case of null cosmological
constant, we provide some updated results on lensing by a Schwarzschild black
hole.Comment: 8 pages, 1 figure; v2: extended discussion on the lens equation,
references added, results unchanged, in press on PR
Testing the Space-Time Structure of Event Generators
We report on work done in collaboration with Klaus Kinder-Geiger and John
Ellis which aims at connecting the space-time structure of event generator
simulations with observable output.Comment: 16 pages LaTeX, including 5 postscript figures. To appear in the
Proceedings of ``RHIC Physics and Beyond - Kay Kay Gee Day'' (Brookhaven
National Laboratory, 23 Oct 1998), ed. by B. Muller and R.D. Pisarski, AIP
Conference Proceeding
N=2 supersymmetric extension of l-conformal Galilei algebra
N=2 supersymmetric extension of the l-conformal Galilei algebra is
constructed. A relation between its representations in flat spacetime and in
Newton-Hooke spacetime is discussed. An infinite-dimensional generalization of
the superalgebra is given.Comment: V4: 8 pages, references and acknowledgements adde
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