882 research outputs found
Targeting the bicarbonate transporter SLC4A4 overcomes immunosuppression and immunotherapy resistance in pancreatic cancer
Electron Energy Loss Spectroscopy Measurement of the Optical Gaps on Individual Boron Nitride Single-Walled and Multiwalled Nanotubes
Spatially resolved electron energy loss spectroscopy experiments have been performed in an electron microscope on several individual boron nitride (BN) single-, double-, and triple-walled nanotubes, whose diameters and number of shells have been carefully measured. In the low-loss region (from 2 to 50 eV) the spectra have been analyzed within the framework of the continuum dielectric theory, leading to the conclusion of a weak influence of out-of-plane contribution to the dielectric response of the tubes. The gap has been measured to be independent of the nanotubes geometry, and close to the in-plane gap value of hexagonal BN (5.8±0.2¿¿eV)
EELS measurements in single wall Boron Nitride nanotubes
We present here the results of an electron energy loss spectroscopy (EELS) study in scanning transmission electron microscopy (STEM) on boron nitride nanotubes (BN-NTs). The low and core-loss regions have been analyzed to provide by the same technique a combined information about chemical bonding in the different materials in the sample and the electronic properties of individual BN-NTs. In particular, we deduce an optical gap value of about 5.8 eV for single walled nanotubes, which is independent on diameter
Finite size effects on thermal denaturation of globular proteins
Finite size effects on the cooperative thermal denaturation of proteins are
considered. A dimensionless measure of cooperativity, Omega, scales as N^zeta,
where N is the number of amino acids. Surprisingly, we find that zeta is
universal with zeta = 1 + gamma, where the exponent gamma characterizes the
divergence of the susceptibility for a self-avoiding walk. Our lattice model
simulations and experimental data are consistent with the theory. Our finding
rationalizes the marginal stability of proteins and substantiates the earlier
predictions that the efficient folding of two-state proteins requires the
folding transition temperature to be close to the collapse temperature.Comment: 3 figures. Physical Review Letters (in press
Exosomes from metastatic cancer cells transfer amoeboid phenotype to non-metastatic cells and increase endothelial permeability: their emerging role in tumor heterogeneity
The goal of this study was to understand if exosomes derived from high-metastatic cells may influence the behavior of less aggressive cancer cells and the properties of the endothelium. We found that metastatic colon cancer cells are able to transfer their amoeboid phenotype to isogenic primary cancer cells through exosomes, and that this morphological transition is associated with the acquisition of a more aggressive behavior. Moreover, exosomes from the metastatic line (SW620Exos) exhibited higher ability to cause endothelial hyperpermeability than exosomes from the non metastatic line (SW480Exos). SWATH-based quantitative proteomic analysis highlighted that SW620Exos are significantly enriched in cytoskeletal-associated proteins including proteins activating the RhoA/ROCK pathway, known to induce amoeboid properties and destabilization of endothelial junctions. In particular, thrombin was identified as a key mediator of the effects induced by SW620Exos in target cells, in which we also found a significant increase of RhoA activity. Overall, our results demonstrate that in a heterogeneous context exosomes released by aggressive sub-clones can contribute to accelerate tumor progression by spreading malignant properties that affect both the tumor cell plasticity and the endothelial cell behavior
Long-Term Effects of Alemtuzumab on CD4+ Lymphocytes in Multiple Sclerosis Patients: A 72-Month Follow-Up
Electron localization and possible phase separation in the absence of a charge density wave in single-phase 1T-VS
We report on a systematic study of the structural, magnetic and transport
properties of high-purity 1T-VS powder samples prepared under high
pressure. The results differ notably from those previously obtained by
de-intercalating Li from LiVS. First, no Charge Density Wave (CDW) is found
by transmission electron microscopy down to 94 K. Though, \textit{ab initio}
phonon calculations unveil a latent CDW instability driven by an acoustic
phonon softening at the wave vector (0.21,0.21,0)
previously reported in de-intercalated samples. A further indication of latent
lattice instability is given by an anomalous expansion of the V-S bond distance
at low temperature. Second, infrared optical absorption and electrical
resistivity measurements give evidence of non metallic properties, consistent
with the observation of no CDW phase. On the other hand, magnetic
susceptibility and NMR data suggest the coexistence of localized moments with
metallic carriers, in agreement with \textit{ab initio} band structure
calculations. This discrepancy is reconciled by a picture of electron
localization induced by disorder or electronic correlations leading to a phase
separation of metallic and non-metallic domains in the nm scale. We conclude
that 1T-VS is at the verge of a CDW transition and suggest that residual
electronic doping in Li de-intercalated samples stabilizes a uniform CDW phase
with metallic properties.Comment: 22 pages, 10 Figures. Full resolution pictures available at
http://journals.aps.org/prb/abstract/10.1103/PhysRevB.89.23512
Investigating the epi-miRNome: Identification of epi-miRNAs using transfection experiments
Aim: Growing evidence shows a strong interplay between post-transcriptional regulation, mediated by miRNAs (miRs) and epigenetic regulation. Nevertheless, the number of experimentally validated miRs (called epi-miRs) involved in these regulatory circuitries is still very small. Material & methods: We propose a pipeline to prioritize candidate epi-miRs and to identify potential epigenetic interactors of any given miR starting from miR transfection experiment datasets. Results & conclusion: We identified 34 candidate epi-miRs: 19 of them are known epi-miRs, while 15 are new. Moreover, using an in-house generated gene expression dataset, we experimentally proved that a component of the polycomb-repressive complex 2, the histone methyltransferase enhancer of zeste homolog 2 (EZH2), interacts with miR-214, a well-known prometastatic miR in melanoma and breast cancer, highlighting a miR-214-EZH2 regulatory axis potentially relevant in tumor progression
A phase Ib study combining the second-generation DNA hypomethylating agent (DHA) guadecitabine (SGI-110) and ipilimumab in patients with metastatic melanoma: The NIBIT-M4 Study
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