262 research outputs found
M. Riesz Theorem on Conjugate Harmonic Functions for Octonion-Valued Monogenic Functions
The classical theorem of M. Riesz about the conjugate harmonic functions is extended onto octonion-valued monogenic functions
Modular Synthetic Approach to Carboranyl‒Biomolecules Conjugates
The development of novel, tumor-selective and boron-rich compounds as potential agents for use in boron neutron capture therapy (BNCT) represents a very important field in cancer treatment by radiation therapy. Here, we report the design and synthesis of two promising compounds that combine meta-carborane, a water-soluble monosaccharide and a linking unit, namely glycine or ethylenediamine, for facile coupling with various tumor-selective biomolecules bearing a free amino or carboxylic acid group. In this work, coupling experiments with two selected biomolecules, a coumarin derivative and folic acid, were included. The task of every component in this approach was carefully chosen: the carborane moiety supplies ten boron atoms, which is a tenfold increase in boron content compared to the l-boronophenylalanine (l-BPA) presently used in BNCT; the sugar moiety compensates for the hydrophobic character of the carborane; the linking unit, depending on the chosen biomolecule, acts as the connection between the tumor-selective component and the boron-rich moiety; and the respective tumor-selective biomolecule provides the necessary selectivity. This approach makes it possible to develop a modular and feasible strategy for the synthesis of readily obtainable boron-rich agents with optimized properties for potential applications in BNCT
Distinct immune signatures in directly treated and distant tumors result from TLR adjuvants and focal ablation.
Both adjuvants and focal ablation can alter the local innate immune system and trigger a highly effective systemic response. Our goal is to determine the impact of these treatments on directly treated and distant disease and the mechanisms for the enhanced response obtained by combinatorial treatments. Methods: We combined RNA-sequencing, flow cytometry and TCR-sequencing to dissect the impact of immunotherapy and of immunotherapy combined with ablation on local and systemic immune components. Results: With administration of a toll-like receptor agonist agonist (CpG) alone or CpG combined with same-site ablation, we found dramatic differences between the local and distant tumor environments, where the directly treated tumors were skewed to high expression of F4/80, Cd11b and Tnf and the distant tumors to enhanced Cd11c, Cd3 and Ifng. When ablation was added to immunotherapy, 100% (n=20/20) of directly treated tumors and 90% (n=18/20) of distant tumors were responsive. Comparing the combined ablation-immunotherapy treatment to immunotherapy alone, we find three major mechanistic differences. First, while ablation alone enhanced intratumoral antigen cross-presentation (up to ~8% of CD45+ cells), systemic cross-presentation of tumor antigen remained low. Combining same-site ablation with CpG amplified cross-presentation in the draining lymph node (~16% of CD45+ cells) compared to the ablation-only (~0.1% of CD45+ cells) and immunotherapy-only cohorts (~10% of CD45+ cells). Macrophages and DCs process and present this antigen to CD8+ T-cells, increasing the number of unique T-cell receptor rearrangements in distant tumors. Second, type I interferon (IFN) release from tumor cells increased with the ablation-immunotherapy treatment as compared with ablation or immunotherapy alone. Type I IFN release is synergistic with toll-like receptor activation in enhancing cytokine and chemokine expression. Expression of genes associated with T-cell activation and stimulation (Eomes, Prf1 and Icos) was 27, 56 and 89-fold higher with ablation-immunotherapy treatment as compared to the no-treatment controls (and 12, 32 and 60-fold higher for immunotherapy-only treatment as compared to the no-treatment controls). Third, we found that the ablation-immunotherapy treatment polarized macrophages and dendritic cells towards a CD169 subset systemically, where CD169+ macrophages are an IFN-enhanced subpopulation associated with dead-cell antigen presentation. Conclusion: While the local and distant responses are distinct, CpG combined with ablative focal therapy drives a highly effective systemic immune response
Serum MicroRNA-21 as a Biomarker for Allergic Inflammatory Disease in Children
MicroRNAs (miRs) have emerged as useful biomarkers for different disease states, including allergic inflammatory diseases such as asthma and eosinophilic esophagitis (EoE). Serum miRs are a possible non-invasive method for diagnosis of such diseases. We focused on microRNA-21 (miR-21) levels in serum, in order to assess the feasibility of using this gene as a non-invasive biomarker for these diseases in the clinic, as well as to better understand the expression pattern of miR-21 in allergic inflammation. We used quantitative PCR (QPCR) to assay miR-21 and other control miRs in esophageal biopsies from EoE patients and serum samples from EoE and asthma patients. Serum levels of miR-21 were significantly elevated in patients with asthma, whereas serum miR-21 levels were not associated with the presence of allergen-specific IgE (i.e. atopy). Esophageal biopsies showed a large elevation of miR-21 in EoE and an increase in miR-21 in EoE serum. Control U6 miR did not vary between asthma and control patients, however EoE serum had significantly decreased U6 microRNA compared to controls. The decreased U6 in EoE sera did not completely account for the relative increase in miR-21 in the sera of EoE patients. We report for the first time that miR-21 is elevated in the sera of both asthma and EoE patients. We find no relation between serum miR-21 levels and atopy. Our results thus suggest miR-21 is a novel biomarker for human allergic inflammatory diseases
Renewal-anomalous-heterogeneous files
Renewal-anomalous-heterogeneous files are solved. A simple file is made of
Brownian hard spheres that diffuse stochastically in an effective 1D channel.
Generally, Brownian files are heterogeneous: the spheres' diffusion
coefficients are distributed and the initial spheres' density is non-uniform.
In renewal-anomalous files, the distribution of waiting times for individual
jumps is exponential as in Brownian files, yet obeys: {\psi}_{\alpha}
(t)~t^(-1-{\alpha}), 0<{\alpha}<1. The file is renewal as all the particles
attempt to jump at the same time. It is shown that the mean square displacement
(MSD) in a renewal-anomalous-heterogeneous file, , obeys,
~[_{nrml}]^{\alpha}, where _{nrml} is the MSD in the
corresponding Brownian file. This scaling is an outcome of an exact relation
(derived here) connecting probability density functions of Brownian files and
renewal-anomalous files. It is also shown that non-renewal-anomalous files are
slower than the corresponding renewal ones.Comment: Accepted for publication (August, 2010
Dopamine-modulated dynamic cell assemblies generated by the GABAergic striatal microcircuit
The striatum, the principal input structure of the basal ganglia, is crucial to both motor control and learning. It receives convergent input from all over the neocortex, hippocampal formation, amygdala and thalamus, and is the primary recipient of dopamine in the brain. Within the striatum is a GABAergic microcircuit that acts upon these inputs, formed by the dominant medium-spiny projection neurons (MSNs) and fast-spiking interneurons (FSIs). There has been little progress in understanding the computations it performs, hampered by the non-laminar structure that prevents identification of a repeating canonical microcircuit. We here begin the identification of potential dynamically-defined computational elements within the striatum. We construct a new three-dimensional model of the striatal microcircuit's connectivity, and instantiate this with our dopamine-modulated neuron models of the MSNs and FSIs. A new model of gap junctions between the FSIs is introduced and tuned to experimental data. We introduce a novel multiple spike-train analysis method, and apply this to the outputs of the model to find groups of synchronised neurons at multiple time-scales. We find that, with realistic in vivo background input, small assemblies of synchronised MSNs spontaneously appear, consistent with experimental observations, and that the number of assemblies and the time-scale of synchronisation is strongly dependent on the simulated concentration of dopamine. We also show that feed-forward inhibition from the FSIs counter-intuitively increases the firing rate of the MSNs. Such small cell assemblies forming spontaneously only in the absence of dopamine may contribute to motor control problems seen in humans and animals following a loss of dopamine cells. (C) 2009 Elsevier Ltd. All rights reserved
- …