1,473 research outputs found
Expression of human milk fat globulin proteins in cells of haemopoietic origin
Lineage-specific gene expression has been used for the identification of metastasis of cancers with unknown primary site or of disseminated cancer cells in haemopoietic compartments such as bone marrow or in lymph nodes. For the muc1, cytokeratin-19 and the CEA genes, the transcription in haemopoietic cells has been shown recently. Here, the expression of the mammary epithelium related antigens BA46 (lactadherin) and BA70 in lymphoid and myeloid cell lines, and in clinical specimens is analysed. By Northern-hybridization with specific oligonucleotides an ubiquitous transcription of both genes, independent from the provenance of cells or the chromosomal gender was found. Both mRNA molecules were amplified by rtPCR from the samples and the specificity could be confirmed by sequence analysis. Peptide-specific antibodies were raised in rabbits and used for Western-blot analysis and for immunocytochemical studies. Both antibodies reacted with total cell lysates from myeloid and lymphatic cells. In immunocytochemistry antibody P717 (anti-lactadherin) had a significant strong staining of the myeloid cell lines K562 and HL60 suggesting a participation of lactadherin in leukocyte-function. Using antibody P718, strong stains were seen in myeloid line K562 and lymphoid line ST486. In conclusion, our findings expand the results that the concept of lineage-specific gene expression is no longer valid at the molecular level. © 2000 Cancer Research Campaig
Nucleon-resonance decay by the K-0 Sigma(+) channel near threshold
For the combined setup of the Crystal Barrel and TAPS at ELSA in Bonn we have proposed to study the reaction gammap --> K(0)Sigma(+). The reaction is characterised by the final state of 6 photons and a forward emitted proton. Here we report on results of simulations to demonstrate the feasibility of the experiment. From the threshold behaviour of the cross section and angular distributions we aim to search for a 3(rd) S-11 resonance just above the KSigma threshold, which may mix with the two lower lying S-11 resonances and thus provide an explanation for the unusually strong eta branching of the S-11(1535) resonance. The hyperon polarisation can be studied as a sensitive tool to determine the various resonance admixtures
Magainin 2 and PGLa in bacterial membrane mimics III : membrane fusion and disruption
We previously speculated that the synergistically enhanced antimicrobial activity of Magainin 2 and PGLa is related to membrane adhesion, fusion, and further membrane remodelling. Here, we combined computer simulations with time-resolved in vitro fluorescence microscopy, cryogenic electron microscopy (cryo-EM), and small-angle X-ray scattering (SAXS) to interrogate such morphological and topological changes of vesicles at nanoscopic and microscopic length scales in real time. Coarse-grained simulations revealed the formation of an elongated and bent fusion zone between vesicles in the presence of equimolar peptide mixtures. Vesicle adhesion and fusion was observed to occur within few seconds by cryo-EM and corroborated by SAXS measurements. The latter experiments further indicated continued and time-extended structural remodelling also for individual peptides or chemically-linked peptide heterodimers, but with different kinetics. Fluorescence microscopy further captured peptide-dependent adhesion, fusion, and occasional bursting of giant unilamellar vesicles already few seconds after peptide addition. The synergistic interactions between the peptides shorten the time response of vesicles and enhance membrane fusogenic and disrupting properties of the equimolar mixture compared to the individual peptides
A High-resolution Adaptive Moving Mesh Hydrodynamic Algorithm
An algorithm for simulating self-gravitating cosmological astrophysical
fluids is presented. The advantages include a large dynamic range,
parallelizability, high resolution per grid element and fast execution speed.
The code is based on a finite volume flux conservative
Total-Variation-Diminishing (TVD) scheme for the shock capturing hydro, and an
iterative multigrid solver for the gravity. The grid is a time dependent field,
whose motion is described by a generalized potential flow. Approximately
constant mass per cell can be obtained, providing all the advantages of a
Lagrangian scheme. The grid deformation combined with appropriate limiting and
smoothing schemes guarantees a regular and well behaved grid geometry, where
nearest neighbor relationships remain constant. The full hydrodynamic fluid
equations are implemented in the curvilinear moving grid, allowing for
arbitrary fluid flow relative to the grid geometry. This combination retains
all the advantages of the grid based schemes including high speed per fluid
element and a rapid gravity solver.
The current implementation is described, and empirical simulation results are
presented. Accurate execution speed calculations are given in terms of floating
point operations per time step per grid cell. This code is freely available to
the community.Comment: 53 pages including 14 figures, submitted to ApJ
Inner approximated reachability analysis
International audienceComputing a tight inner approximation of the range of a function over some set is notoriously di cult, way beyond obtaining outer approximations. We propose here a new method to compute a tight inner approximation of the set of reachable states of non-linear dynamical systems on a bounded time interval. This approach involves a ne forms and Kaucher arithmetic, plus a number of extra ingredients from set-based methods. An implementation of the method is discussed, and illustrated on representative numerical schemes, discrete-time and continuous-time dynamical systems
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