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101.
Carole Yaacoub Mariam Rifi Dany El-Obeid Hiba Mawlawi Jean-Marc Sabatier Bruno Coutard Ziad Fajloun 《Molecules (Basel, Switzerland)》2021,26(8)
Colon carcinogenesis is ranked second globally among human diseases after cardiovascular failures. Bee venom (BV) has been shown to possess in vitro anticancer effects against several types of cancer cells. The two main biopeptides of Apis mellifera BV, namely, melittin (MEL) and phospholipase A2 (PLA2), are suspected to be the biomolecules responsible for the anticancer activity. The present work aims to evaluate the cytotoxic effect of the A. mellifera venom on human colon carcinoma cells (HCT116), and to assess the synergistic effect of MEL and PLA2 on these cells. After analyzing, through high-pressure liquid chromatography, the proportions of MEL and PLA2 on BV, we have established a cell viability assay to evaluate the effect of BV, MEL, PLA2, and a mixture of MEL and PLA2 on the HCT116 cells. Results obtained showed a strong cytotoxicity effect induced by the A. mellifera venom and to a lower extent MEL or PLA2 alone. Remarkably, when MEL and PLA2 were added together, their cytotoxic effect was greatly improved, suggesting a synergistic activity on HCT116 cells. These findings confirm the cytotoxic effect of the A. mellifera venom and highlight the presence of synergistic potential activities between MEL and PLA2, possibly inducing membrane disruption of HCT116 cancer cells. Altogether, these results could serve as a basis for the development of new anticancer treatments. 相似文献
102.
This article extends our previous analysis Stránský et al. (2014) of Excited-State Quantum Phase Transitions (ESQPTs) in systems of dimension two. We focus on the oscillatory component of the quantum state density in connection with ESQPT structures accompanying a first-order ground-state transition. It is shown that a separable (integrable) system can develop rather strong finite-size precursors of ESQPT expressed as singularities in the oscillatory component of the state density. The singularities originate in effectively 1-dimensional dynamics and in some cases appear in multiple replicas with increasing excitation energy. Using a specific model example, we demonstrate that these precursors are rather resistant to proliferation of chaotic dynamics. 相似文献
103.
Alicia Maroto Dany Jeanne dit Fouque Rémy Lartia Antony Memboeuf 《Journal of mass spectrometry : JMS》2024,59(5):e5025
Energy-resolved mass spectrometry (ERMS) and an isotopically labelled internal standard were successfully combined to accurately quantify a tryptic peptide despite the presence of an isobaric interference. For this purpose, electrospray ionisation tandem mass spectrometry (ESI-MS/MS) experiments were conducted into an ion trap instrument using an unconventional 8 m/z broadband isolation window, which encompassed both the tryptic peptide and its internal standard. Interference removal was assessed by determining an excitation voltage that was high enough to maintain a constant value for the analyte/internal standard peaks intensity ratio, thus ensuring accurate quantification even in the presence of isobaric contamination. Pseudo-multiple reaction monitoring (MRM) was employed above this excitation voltage to quantify the trypic peptide. The internal standard calibration model showed no lack of fit and exhibited a linear dynamic range from 0.5 μM up to 2.5 μM. The detection limit was 0.08 μM. The accuracy of the method was evaluated by quantifying the tryptic peptide of three reference samples intentionally contaminated with the isobaric interference. All the reference samples were accurately quantified with ∼1% deviation despite the isobaric contamination. Furthermore, we have demonstrated that this methodology can also be applied to quantify the isobaric peptide by standard additions down to 0.2 μM. Finally, liquid chromatography ERMS (LC ERMS) experiments yielded similar results, suggesting the potential of the proposed methodology for analysing complex samples. 相似文献
104.
We prove that a convex functionf ∈ L
p[−1, 1], 0<p<∞, can be approximated by convex polynomials with an error not exceeding Cω
3
ϕ
(f,1/n)p where ω
3
ϕ
(f,·) is the Ditzian-Totik modulus of smoothness of order three off. We are thus filling the gap between previously known estimates involving ω
3
ϕ
(f,1/n)p, and the impossibility of having such estimates involving ω4. We also give similar estimates for the approximation off by convexC
0 andC
1 piecewise quadratics as well as convexC
2 piecewise cubic polynomials.
Communicated by Dietrich Braess 相似文献
105.
Summary The paper deals with approximation of a continuous function, on a finite interval, which changes convexity finitely many times,
by algebraic polynomials which are coconvex with it. We give final answers to open questions concerning the validity of Jackson
type estimates involving the weighted Ditzian-Totik moduli of smoothness. 相似文献
106.
In recent years there have been various attempts at the
representations of {\mbox multivariate} signals such as images, which
outperform wavelets. As is well known, wavelets are not optimal in
that they do not take full advantage of the geometrical
regularities and singularities of the images. Thus these
approaches have been based on tracing curves of singularities and
applying bandlets, curvelets, ridgelets, etc., or allocating some weights to curves of
singularities like the Mumford–Shah functional and its
modifications. In the latter approach a function is approximated
on subdomains where it is smoother but there is a penalty in the
form of the total length (or other measurement) of the
partitioning curves. We introduce a combined measure of smoothness
of the function in several dimensions by augmenting its smoothness
on subdomains by the smoothness of the partitioning curves.
Also, it is known that classical smoothness spaces fail to
characterize approximation spaces corresponding to multivariate
piecewise polynomial nonlinear approximation. We show how the
proposed notion of smoothness can almost characterize these
spaces. The question whether the characterization proposed in this
work can be further simplified remains open. 相似文献
107.
R. A. DeVore G. Kyriazis D. Leviatan V. M. Tikhomirov 《Advances in Computational Mathematics》1993,1(2):197-214
It is shown that certain algorithms of compression based on wavelet decompositions are optimal in the sense of nonlinearn-widths.This research was supported by the Office of Naval Research Contract N0014-91-J1343 and a Binational Science Foundation Grant 89-00505.This research was completed while D. Leviatan and V.M. Tikhomirov were visiting scholars at the University of South Carolina. 相似文献
108.
A. Leviatan 《Zeitschrift für Physik A Hadrons and Nuclei》1985,321(3):467-472
We discuss the spontaneous symmetry breaking of O(3) and O(5) rotations occurring in an exact ground state of certain schematic IBM-interactions. The ground state is a condensate built from one of six bosons forming a general non-spherical boson basis whose members depend continuously on the deformation parametersβ andγ. Interpreting some of the basis members as Goldstone bosons allows a convenient separation between bosons representing physical and spurious modes. The schematic interactions are shown to be suitable for forming Hamiltonians whose eigenstates are clustered into bands. 相似文献
109.
110.