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Found 37769 matches. Displaying 3341-3350
Bellat V, Ting R, Southard TL, Vandat L, Molina H, Fernandez J, Aras O, Stokol T, Law B
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Functional Peptide Nanofibers with Unique Tumor Targeting and Enzyme-Induced Local Retention Properties

ADVANCED FUNCTIONAL MATERIALS 2018 OCT 31; 28(44):? Article 1803969
An effective tumoral delivery system should show minimal removal by the reticuloendothelial system (RES), promote tumor uptake and penetration, and minimize on-site clearance. This study reports the design and synthesis of advanced self-assembling peptide nanofiber precursor (NFP) analogues. The peptidic nature of NFP offers the design flexibility for on-demand customization with imaging agents and surface charges while maintaining a set size, allowing for real-time monitoring of kinetic and dynamic tumoral delivery by multimodal fluorescence/positron emission tomography/computed tomography (fluo/PET/CT) imaging, for formulation optimization. The optimized glutathione (GSH)-NFP displays a reduced capture by the RES as well as excellent tumor targeting and tissue invasion properties compared to naive NFP. Inside a tumor, GSH-NFP can structurally transform into ten times larger interfibril networks, serving as in situ depot that promotes weeks-long local retention. This nanofiber, which can further be designed to release the active pharmacophores within a tumor microenvironment, displays a superior therapeutic efficacy for inhibiting disease progression and improving the survival of animals bearing triple-negative breast cancer tumors compared to free drug and liposome formulation of the drug, in addition to a favorable toxicity profile.
Boyden E, Guo S, Klein R, Rico B, Ruta V
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Building a Better Brain

CELL 2018 OCT 18; 175(3):633-634
What would it take to engineer a brain circuit to perform a new kind of computation or to augment an existing brain computation with additional information? Perhaps you could augment a memory circuit (starting with, say, a mouse) so that it could tap into digital data, boost the capacity of working memory so that dozens of things could be held in mind at once, or enable algorithms from computer science to be run on in-brain wetware.
Nacev BA, Tap WD
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TOMAS: revisiting PARP inhibitor combination therapy

LANCET ONCOLOGY 2018 OCT; 19(10):1269-1270
Chang GQ, Karatayev O, Halkina V, Edelstien J, Ramirez E, Leibowitz SF
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Hypothalamic CCL2/CCR2 Chemokine System: Role in Sexually Dimorphic Effects of Maternal Ethanol Exposure on Melanin-Concentrating Hormone and Behavior in Adolescent Offspring

JOURNAL OF NEUROSCIENCE 2018 OCT 17; 38(42):9072-9090
Clinical and animal studies show that ethanol exposure and inflammation during pregnancy cause similar behavioral disturbances in the offspring. While ethanol is shown to stimulate both neuroimmune and neurochemical systems in adults, little is known about their anatomical relationship in response to ethanol in utero and whether neuroimmune factors mediate ethanol's effects on neuronal development and behavior in offspring. Here we examined in female and male adolescent rats a specific population of neurons concentrated in lateral hypothalamus, which coexpress the inflammatory chemokine C-C motif ligand 2 (CCL2) or its receptor CCR2 with the orexigenic neuropeptide, melanin-concentrating hormone (MCH), that promotes ethanol drinking behavior. We demonstrate that maternal administration of ethanol (2 g/kg/d) from embryonic day 10 (E10) to E15, while having little impact on glia, stimulates expression of neuronal CCL2 and CCR2, increases density of both large CCL2 neurons colocalizing MCH and small CCL2 neurons surrounding MCH neurons, and stimulates ethanol drinking and anxiety in adolescent offspring. We show that these neuronal and behavioral changes are similarly produced by maternal administration of CCL2 (4 or 8 mu g/kg/d, E10-E15) and blocked by maternal administration of a CCR2 antagonist INCB3344 (1 mg/kg/d, E10-E15), and these effects of ethanol and CCL2 are sexually dimorphic, consistently stronger in females. These results suggest that this neuronal CCL2/CCR2 system closely linked to MCH neurons has a role in mediating the effects of maternal ethanol exposure on adolescent offspring and contributes to the higher levels of adolescent risk factors for alcohol use disorders described in women.
Suryawanshi H, Morozov P, Straus A, Sahasrabudhe N, Max KEA, Garzia A, Kustagi M, Tuschl T, Williams Z
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A single-cell survey of the human first-trimester placenta and decidua

SCIENCE ADVANCES 2018 OCT; 4(10):? Article eaau4788
The placenta and decidua interact dynamically to enable embryonic and fetal development. Here, we report single-cell RNA sequencing of 14,341 and 6754 cells from first-trimester human placental villous and decidual tissues, respectively. Bioinformatic analysis identified major cell types, many known and some subtypes previously unknown in placental villi and decidual context. Further detailed analysis revealed proliferating subpopulations, enrichment of cell type-specific transcription factors, and putative intercellular communication in the fetomaternal microenvironment. This study provides a blueprint to further the understanding of the roles of these cells in the placenta and decidua for maintenance of early gestation as well as pathogenesis in pregnancy-related disorders.
Behesti H, Fore TR, Wu P, Horn Z, Leppert M, Hull C, Hatten ME
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ASTN2 modulates synaptic strength by trafficking and degradation of surface proteins

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2018 OCT 9; 115(41):E9717-E9726
Surface protein dynamics dictate synaptic connectivity and function in neuronal circuits. ASTN2, a gene disrupted by copy number variations (CNVs) in neurodevelopmental disorders, including autism spectrum, was previously shown to regulate the surface expression of ASTN1 in glial-guided neuronal migration. Here, we demonstrate that ASTN2 binds to and regulates the surface expression of multiple synaptic proteins in postmigratory neurons by endocytosis, resulting in modulation of synaptic activity. In cerebellar Purkinje cells (PCs), by immunogold electron microscopy, ASTN2 localizes primarily to endocytic and autophagocytic vesicles in the cell soma and in subsets of dendritic spines. Overexpression of ASTN2 in PCs, but not of ASTN2 lacking the FNIII domain, recurrently disrupted by CNVs in patients, including in a family presented here, increases inhibitory and excitatory postsynaptic activity and reduces levels of ASTN2 binding partners. Our data suggest a fundamental role for ASTN2 in dynamic regulation of surface proteins by endocytic trafficking and protein degradation.
Brown M, Cohen JE
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SQUARED COEFFICIENT OF VARIATION OF TAYLOR ' S LAW FOR RANDOM ABSOLUTE DIFFERENCES

PROBABILITY IN THE ENGINEERING AND INFORMATIONAL SCIENCES 2018 OCT; 32(4):483-494
In a family, parameterized by theta, of non-negative random variables with finite, positive second moment, Taylor's law (TL) asserts that the population variance is proportional to a power of the population mean as theta varies: sigma(2)(theta) = alpha[mu(theta)](b) , alpha > 0. TL, sometimes called fluctuation scaling, holds widely in science, probability theory, and stochastic processes. Here we report diverse examples of TL with b = 2 (equivalent to a constant coefficient of variation) arising from a difference of random variables in normed vector spaces of dimension 1 and larger. In these examples, we compute alpha exactly using, in some cases, a simple, new technique. These examples may prove useful in future models that involve differences of random variables, including models of the spatial distribution and migration of human populations.
Raz A, Serrano A, Thaker M, Alston T, Fischetti VA
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Lysostaphin Lysibody Leads to Effective Opsonization and Killing of Methicillin-Resistant Staphylococcus aureus in a Murine Model

ANTIMICROBIAL AGENTS AND CHEMOTHERAPY 2018 OCT; 62(10):? Article e01056-18
The cell wall of Gram-positive bacteria contains abundant surfaceexposed carbohydrate structures that are highly conserved. While these properties make surface carbohydrates ideal targets for immunotherapy, carbohydrates elicit a poor immune response that results primarily in low-affinity IgM antibodies. In a previous publication, we introduced the lysibody approach to address this shortcoming. Lysibodies are engineered molecules that combine a high-affinity carbohydrate-binding domain of bacterial or bacteriophage origin and an Fc effector portion of a human IgG antibody, thus directing effective immunity to conserved bacterial surface carbohydrates. Here, we describe the first example of a lysibody containing the binding domain from a bacteriocin, lysostaphin. We also describe the creation of five lysibodies with binding domains derived from phage lysins, directed against Staphylococcus aureus. The lysostaphin and LysK lysibodies showed the most promise and were further characterized. Both lysibodies bound a range of clinically important staphylococcal strains, fixed complement on the staphylococcal surface, and induced phagocytosis of S. aureus by macrophages and human neutrophils. The lysostaphin lysibody had superior in vitro activity compared to that of the LysK lysibody, as well as that of the previously characterized ClyS lysibody, and it effectively protected mice in a kidney abscess/bacteremia model. These results further demonstrate that the lysibody approach is a reproducible means of creating antibacterial antibodies that cannot be produced by conventional means. Lysibodies therefore are a promising solution for opsonic antibodies that may be used passively to both treat and prevent infection by drug-resistant pathogens.
Petrelli A, Mijnheer G, van Konijnenburg DPH, van der Wal MM, Giovannone B, Mocholi E, Vazirpanah N, Broen JC, Hijnen D, Oldenburg B, Coffer PJ, Vastert SJ, Prakken BJ, Spierings E, Pandit A, Mokry M, van Wijk F
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PD-1(+)CD8(+) T cells are clonally expanding effectors in human chronic inflammation

JOURNAL OF CLINICAL INVESTIGATION 2018 OCT 1; 128(10):4669-4681
Chronic inflammatory diseases are characterized by recurrent inflammatory attacks in the tissues mediated by autoreactive T cells. Identity and functional programming of CD8(+) T cells at the target site of inflammation still remain elusive. One key question is whether, in these antigen-rich environments, chronic stimulation leads to CD8(+) T cell exhaustion comparable to what is observed in infectious disease contexts. In the synovial fluid (SF) of juvenile idiopathic arthritis (JIA) patients, a model of chronic inflammation, an overrepresentation of PD-1(+)CD8(+) T cells was found. Gene expression profiling, gene set enrichment analysis, functional studies, and extracellular flux analysis identified PD-1(+)CD8(+ )T cells as metabolically active effectors, with no sign of exhaustion. Furthermore, PD-1(+)CD8(+) T cells were enriched for a tissue-resident memory (Trm) cell transcriptional profile and demonstrated increased clonal expansion compared with the PD-1(-) counterpart, suggesting antigen-driven expansion of locally adapted cells. Interestingly, this subset was also found increased in target tissues in other human chronic inflammatory diseases. These data indicate that local chronic inflammation drives the induction and expansion of CD8(+) T cells endowed with potential detrimental properties. Together, these findings lay the basis for investigation of PD-1-expressing CD8(+) T cell targeting strategies in human chronic inflammatory diseases.
Lorenzen E, Ceraudo E, Berchiche YA, Rico CA, Furstenberg A, Sakmar TP, Huber T
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G protein subtype-specific signaling bias in a series of CCR5 chemokine analogs

SCIENCE SIGNALING 2018 OCT 16; 11(552):? Article eaao6152
Chemokines and some chemical analogs of chemokines prevent cellular HIV-1 entry when bound to the HIV-1 coreceptors C-C chemokine receptor 5 (CCR5) or C-X-C chemokine receptor 4 (CXCR4), which are G protein-coupled receptors (GPCRs). The ideal HIV-1 entry blocker targeting the coreceptors would display ligand bias and avoid activating G protein-mediated pathways that lead to inflammation. We compared CCR5-dependent activation of second messenger pathways in a single cell line. We studied two endogenous chemokines [ RANTES (also known as CCL5) and MIP-1. (also known as CCL3)] and four chemokine analogs of RANTES (5P12-, 5P14-, 6P4-, and PSC-RANTES). We found that CCR5 signaled through both G(i/o) and G(q/11). IP1 accumulation and Ca2+ flux arose from G(q/11) activation, rather than from G beta gamma subunit release after Gi/o activation as had been previously proposed. The 6P4-and PSC-RANTES analogs were superagonists for G(q/11) activation, whereas the 5P12- and 5P14-RANTES analogs displayed a signaling bias for G(i/o). These results demonstrate that RANTES analogs elicit G protein subtype-specific signaling bias and can cause CCR5 to couple preferentially to G(q/11) rather than to Gi/o signaling pathways. We propose that G protein subtype-specific signaling bias may be a general feature of GPCRs that can couple to more than one G protein family.