30 research outputs found
Weighted sums with two parameters of multiple zeta values and their formulas
A typical formula of multiple zeta values is the sum formula which expresses
a Riemann zeta value as a sum of all multiple zeta values of fixed weight and
depth. Recently weighted sum formulas, which are weighted analogues of the sum
formula, have been studied by many people. In this paper, we give two formulas
of weighted sums with two parameters of multiple zeta values. As applications
of the formulas, we find some linear combinations of multiple zeta values which
can be expressed as polynomials of usual zeta values with coeffcients in the
rational polynomial ring generated by the two parameters, and obtain some
identities for weighted sums of multiple zeta values of small depths.Comment: 14 page
Suppression of Met/HGF Receptor Activation by the Met Juxtamembrane Function and Cell-Cell Contact
Division of Tumor Dynamics and Regulatio
Cell-signalling dynamics in time and space
The specificity of cellular responses to receptor stimulation is encoded by the spatial and temporal dynamics of downstream signalling networks. Computational models provide insights into the intricate relationships between stimuli and responses and reveal mechanisms that enable networks to amplify signals, reduce noise and generate discontinuous bistable dynamics or oscillations. These temporal dynamics are coupled to precipitous spatial gradients of signalling activities, which guide pivotal intracellular processes, but also necessitate mechanisms to facilitate signal propagation across a cell
Congruence identities of regularized multiple zeta values involving a pair of index sets
Suppression of Met/HGF Receptor Activation by the Met Juxtamembrane Function and Cell-Cell Contact
State-of-the-Art Review: Unraveling Distinct Intracellular Signals That Promote Survival and Proliferation: Study of Erythropoietin, Stem Cell Factor, and Constitutive Signaling in Leukemic Cells
Tec family kinases in T lymphocyte development and function
The Tec family tyrosine kinases are now recognized as important mediators of antigen receptor signaling in lymphocytes. Three members of this family, Itk, Rlk, and Tec, are expressed in T cells and activated in response to T cell receptor (TCR) engagement. Although initial studies demonstrated a role for these proteins in TCR-mediated activation of phospholipase C-gamma, recent data indicate that Tec family kinases also regulate actin cytoskeletal reorganization and cellular adhesion following TCR stimulation. In addition, Tec family kinases are activated downstream of G protein-coupled chemokine receptors, where they play parallel roles in the regulation of Rho GTPases, cell polarization, adhesion, and migration. In all these systems, however, Tec family kinases are not essential signaling components, but instead function to modulate or amplify signaling pathways. Although they quantitatively reduce proximal signaling, mutations that eliminate Tec family kinases in T cells nonetheless qualitatively alter T cell development and differentiation
Effect of antiangiogenic therapy on tumor growth, vasculature and kinase activity in basal- and luminal-like breast cancer xenografts
Several clinical trials have investigated the efficacy of bevacizumab in breast cancer, and
even if growth inhibiting effects have been registered when antiangiogenic treatment is
given in combination with chemotherapy no gain in overall survival has been observed.
One reason for the lack of overall survival benefit might be that appropriate criteria for selection of patients likely to respond to antiangiogenic therapy in combination with chemotherapy, are not available.
To determine factors of importance for antiangiogenic treatment response and/or resistance, two representative human basal- and luminal-like breast cancer xenografts were
treated with bevacizumab and doxorubicin alone or in combination. In vivo growth inhibition, microvessel density (MVD) and proliferating tumor vessels (pMVD ¼ proliferative microvessel density) were analysed, while kinase activity was determined using the PamChip
Tyrosine kinase microarray system.
Results showed that both doxorubicin and bevacizumab inhibited basal-like tumor growth
significantly, but with a superior effect when given in combination. In contrast, doxorubicin inhibited luminal-like tumor growth most effectively, and with no additional benefit of
adding antiangiogenic therapy. In agreement with the growth inhibition data, vascular
characterization verified a more pronounced effect of the antiangiogenic treatment in
the basal-like compared to the luminal-like tumors, demonstrating total inhibition of
pMVD and a significant reduction in MVD at early time points (three days after treatment)
and sustained inhibitory effects until the end of the experiment (day 18). In contrast,
luminal-like tumors only showed significant effect on the vasculature at day 10 in the tumors having received both doxorubicin and bevacizumab.
Kinase activity profiling in both tumor models demonstrated that the most effective
treatment in vivo was accompanied with increased phosphorylation of kinase substrates of growth control and angiogenesis, like EGFR, VEGFR2 and PLCg1. This may be a result
of regulatory feedback mechanisms contributing to treatment resistance, and may
suggest response markers of value for the prediction of antiangiogenic treatment
efficacy
