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Synaptic dysfunction and loss caused by age-dependent accumulation of synaptotoxic beta amyloid (Abeta) 1-42 oligomers is proposed to underlie cognitive decline in Alzheimer's disease (AD). Alterations in membrane trafficking induced by Abeta oligomers mediates reduction in neuronal surface receptor expression that is the basis for inhibition of electrophysiological measures of synaptic plasticity and thus learning and memory. We have utilized phenotypic screens in mature, in vitro cultures of rat brain cells to identify small molecules which block or prevent the binding and effects of Abeta oligomers. Synthetic Abeta oligomers bind saturably to a single site on neuronal synapses and induce deficits in membrane trafficking in neuronal cultures with an EC50 that corresponds to its binding affinity. The therapeutic lead compounds we have found are pharmacological antagonists of Abeta oligomers, reducing the binding of Abeta oligomers to neurons in vitro, preventing spine loss in neurons and preventing and treating oligomer-induced deficits in membrane trafficking. These molecules are highly brain penetrant and prevent and restore cognitive deficits in mouse models of Alzheimer's disease. Counter-screening these compounds against a broad panel of potential CNS targets revealed they are highly potent and specific ligands of the sigma-2/PGRMC1 receptor. Brain concentrations of the compounds corresponding to greater than 80% receptor occupancy at the sigma-2/PGRMC1 receptor restore cognitive function in transgenic hAPP Swe/Ldn mice. These studies demonstrate that synthetic and human-derived Abeta oligomers act as pharmacologically-behaved ligands at neuronal receptors--i.e. they exhibit saturable binding to a target, they exert a functional effect related to their binding and their displacement by small molecule antagonists blocks their functional effect. The first-in-class small molecule receptor antagonists described here restore memory to normal in multiple AD models and sustain improvement long-term, representing a novel mechanism of action for disease-modifying Alzheimer's therapeutics.

Pathophysiological conditions that lead to the release of the prototypic damage-associated molecular pattern molecule high mobility group box 1 (HMGB1) also result in activation of poly(ADP-ribose) polymerase 1 (PARP1; now known as ADP-ribosyl transferase 1 [ARTD1]). Persistent activation of PARP1 promotes energy failure and cell death. The role of poly(ADP-ribosyl)ation in HMGB1 release has been explored previously; however, PARP1 is a versatile enzyme and performs several other functions including cross-talk with another nicotinamide adenine dinucleotide-(NAD + ) dependent member of the Class III histone deacetylases (HDACs), sirtuin-1 (SIRT1). Previously, it has been shown that the hyperacetylation of HMGB1 is a seminal event prior to its secretion, a process that also is dependent on HDACs. Therefore, in this study, we seek to determine if PARP1 inhibition alters LPS-mediated HMGB1 hyperacetylation and subsequent secretion due to its effect on SIRT1. We demonstrate in an in vitro model that LPS treatment leads to hyperacetylated HMGB1with concomitant reduction in nuclear HDAC activity. Treatment with PARP1 inhibitors mitigates the LPS-mediated reduction in nuclear HDAC activity and decreases HMGB1 acetylation. By utilizing an NAD + -based mechanism, PARP1 inhibition increases the activity of SIRT1. Consequently, there is an increased nuclear retention and decreased extracellular secretion of HMGB1. We also demonstrate that PARP1 physically interacts with SIRT1. Further confirmation of this data was obtained in a murine model of sepsis, that is, administration of PJ-34, a specific PARP1 inhibitor, led to decreased serum HMGB1 concentrations in mice subjected to cecal ligation and puncture (CLP) as compared with untreated mice. In conclusion, our study provides new insights in understanding the molecular mechanisms of HMGB1 secretion in sepsis.

Understanding how microscopic spin configuration gives rise to exotic properties at the macroscopic length scale has long been pursued in magnetic materials 1 – 5 . One seminal example is the Einstein–de Haas effect in ferromagnets 1 , 6 , 7 , in which angular momentum of spins can be converted into mechanical rotation of an entire object. However, for antiferromagnets without net magnetic moment, how spin ordering couples to macroscopic movement remains elusive. Here we observed a seesaw-like rotation of reciprocal lattice peaks of an antiferromagnetic nanolayer film, whose gigahertz structural resonance exhibits more than an order-of-magnitude amplification after cooling below the Néel temperature. Using a suite of ultrafast diffraction and microscopy techniques, we directly visualize this spin-driven rotation in reciprocal space at the nanoscale. This motion corresponds to interlayer shear in real space, in which individual micro-patches of the film behave as coherent oscillators that are phase-locked and shear along the same in-plane axis. Using time-resolved optical polarimetry, we further show that the enhanced mechanical response strongly correlates with ultrafast demagnetization, which releases elastic energy stored in local strain gradients to drive the oscillators. Our work not only offers the first microscopic view of spin-mediated mechanical motion of an antiferromagnet but it also identifies a new route towards realizing high-frequency resonators 8 , 9 up to the millimetre band, so the capability of controlling magnetic states on the ultrafast timescale 10 – 13 can be readily transferred to engineering the mechanical properties of nanodevices. Using several ultrafast diffraction and microscopy techniques, demagnetization-driven interlayer shear of a van der Waals antiferromagnet is visualized at the nanoscale.

Atmospheric dynamical cores are a fundamental component of global atmospheric modeling systems and are responsible for capturing the dynamical behavior of the Earth's atmosphere via numerical integration of the Navier–Stokes equations. These systems have existed in one form or another for over half of a century, with the earliest discretizations having now evolved into a complex ecosystem of algorithms and computational strategies. In essence, no two dynamical cores are alike, and their individual successes suggest that no perfect model exists. To better understand modern dynamical cores, this paper aims to provide a comprehensive review of 11 non-hydrostatic dynamical cores, drawn from modeling centers and groups that participated in the 2016 Dynamical Core Model Intercomparison Project (DCMIP) workshop and summer school. This review includes a choice of model grid, variable placement, vertical coordinate, prognostic equations, temporal discretization, and the diffusion, stabilization, filters, and fixers employed by each system.

Albumin-bound paclitaxel, ABI-007 (Abraxane((R))), has a different toxicity profile than solvent-based paclitaxel, including a lower rate of severe neutropenia. The combination of ABI-007 and carboplatin may have significant activity in a variety of tumor types including non-small and small cell lung cancer, ovarian cancer, and breast cancer. The purpose of this study was to determine the maximum tolerated dose (MTD) of ABI-007, on three different schedules in combination with carboplatin. Forty-one patients with solid tumors were enrolled, and received ABI-007 in combination with carboplatin AUC of 6 on day 1. Group A received ABI-007 at doses ranging from 220 to 340 mg/m(2) on day 1 every 21 days; group B received ABI-007 at 100 or 125 mg/m(2) on days 1, 8, and 15 every 28 days; and group C received ABI-007 125 or 150 mg/m(2) on days 1 and 8 every 21 days. Dose-limiting toxicities were assessed after the first cycle. Doses were escalated in cohorts of three to six patients. Fifteen patients participated in a pharmacokinetic study investigating the effects of the sequence of infusion. ABI-007 was infused first followed by carboplatin in cycle 1, and vice versa in cycle 2. The MTD of ABI-007 in combination with carboplatin was 300, 100, and 125 mg/m(2) in groups A, B, and C, respectively. Myelosuppression was the primary dose limiting toxicity. No unexpected or new toxicities were reported. Sequence of infusion did not affect either the pharmacokinetics of ABI-007 or the degree of neutropenia. Responses were seen in melanoma, lung, bladder, esophageal, pancreatic, breast cancer, and cancer of unknown primary. The recommended dose for phase II studies of ABI-007 in combination with carboplatin (AUC of 6) is 300, 100, 125 mg/m(2) for the schedules A, B, and C, respectively. The combination of ABI-007 and carboplatin is well tolerated and active in this heavily pretreated patient population.

Purpose The objectives of this study were to determine whether the midazolam clearance predicted docetaxel pharmacokinetics, CA-125 change, and response and to assess the impact of cytochrome P450 (CYP) 3A5 and ATP-binding cassette, subfamily B, member 1 (ABCB1) genotypes on docetaxel pharmacokinetics and pharmacodynamics in ovarian or primary peritoneal cancer patients. Methods Thirty-four patients with advanced ovarian and primary peritoneal cancer were administered docetaxel at 75 mg/m 2 as a 1-h infusion in combination with carboplatin IV over 30 min at a target AUC of 5 mg/ml min. Cycles were repeated every 21 days for 6 cycles. Midazolam was administered at 2 mg as a 30-min IV infusion the day prior to cycle one of docetaxel administration. Pharmacokinetic studies of docetaxel and CYP3A5 and ABCB1 genotype studies were performed. Results There was an inverse relationship between midazolam clearance (CL) and CA-125 level after cycle 6 where a higher midazolam CL was associated with a CA-125 <10 U/ml ( P  = 0.007) and CA-125 <15 U/ml ( P  = 0.048). The CA-125 categories were associated with response achieved (complete response/partial response) (CR/PR), stable disease (SD), and progressive disease (PD) at the end of therapy ( P  = 0.0173). Docetaxel CL was not related to midazolam CL or genotype. Docetaxel exposure and genotypes were not related to toxicity or response ( P  > 0.05). Conclusions The midazolam CL predicted CA-125 levels and response that was independent of other factors including docetaxel pharmacokinetics. Future studies need to evaluate the mechanism for the relationship between midazolam CL and response in patients with ovarian cancer.

Summary Purpose. Epidermal growth factor receptor (EGFR) inhibition may overcome chemotherapy resistance by inhibiting important anti-apoptotic signals that are constitutively activated by an overstimulated EGFR pathway. Methods. This phase I dose escalation trial assessed the safety and efficacy of vinflunine, a novel vinca alkaloid microtubule inhibitor, with erlotinib, an EGFR tyrosine kinase inhibitor, in patients with refractory solid tumors. Results . Seventeen patients were treated, 10 with continuous erlotinib, and 7 with intermittent erlotinib. At dose level 1, vinflunine 280 mg/m 2 IV day 1 and erlotinib 75 mg PO days 2–21 (“continuous erlotinib”) in 21 day cycles, two of four patients experienced DLTs. At dose level −1 (vinflunine 250 mg/m 2 every 21 days and erlotinib 75 mg/day), two of six patients experienced DLTs. The study was amended to enroll to “intermittent erlotinib” dosing: vinflunine day 1 and erlotinib days 2–15 of a 21 day cycle. Two of seven experienced DLTs and the study was terminated. One patient with breast cancer had a partial response; three had stable disease ≥6 cycles. All were treated in the continuous erlotinib group. Conclusions . Given the marked toxicity in our patient population, the combination of vinflunine and erlotinib cannot be recommended for further study with these dosing schemas.

Summary Background Vinflunine is a novel vinca alkaloid with promising single agent clinical activity. Pemetrexed has at least additive activity with other vincas. A phase I trial was undertaken to assess the safety of vinflunine and pemetrexed in patients with refractory solid tumors. Methods A standard 3-patient cohort dose escalation scheme was used to determine the dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) of the vinflunine/pemetrexed combination. Pemetrexed 500 mg/m 2 was given with vinflunine 280 mg/m 2 (cohort 1), 300 mg/m 2 (cohort 2) or 320 mg/m 2 (cohort 3) on day 1 of a 21-day cycle. Results 19 patients were enrolled, median age 58 years (range 32 to 77) and had a median of 3 (range 1–6) prior therapies. DLT occured 1 of 6 pts in cohort 1 (thrombocytopenia, hyponatremia), 2 of 10 pts in cohort 2 (febrile neutropenia, hyponatremia, hyperbilirubinema; febrile neutropenia), and 2 of 3 pts in cohort 3 (febrile neutropenia, hypokalemia; febrile neutropenia). 1 pt in cohort 2 died prior to completion of cycle 1 likely from disease progression. Most common grade 3/4 adverse events were neutropenia (7), leukopenia (5). Febrile neutropenia occurred in 4 patients (21%). No objective responses were seen. Two patients (breast and lung) had prolonged stable disease for 25 and 20 cycles respectively. Conclusions Based on this experience we recommend vinflunine 300 mg/m 2 and pemetrexed 500 mg/m 2 in combination every 3 weeks for future study. At these doses, the combination of vinflunine and pemetrexed was tolerable in this heavily pretreated population. Hematologic toxicity, including febrile neutropenia, was prominent.

The development of next generation perovskite-based optoelectronic devices relies critically on the understanding of the interaction between charge carriers and the polar lattice in out-of-equilibrium conditions. While it has become increasingly evident for CsPbBr3 perovskites that the Pb-Br framework flexibility plays a key role in their light-activated functionality, the corresponding local structural rearrangement has not yet been unambiguously identified. In this work, we demonstrate that the photoinduced lattice changes in the system are due to a specific polaronic distortion, associated with the activation of a longitudinal optical phonon mode at 18 meV by electron-phonon coupling, and we quantify the associated structural changes with atomic-level precision. Key to this achievement is the combination of time-resolved and temperature-dependent studies at Br K-edge and Pb L3-edge X-ray absorption with refined ab-initio simulations, which fully account for the screened core-hole final state effects on the X-ray absorption spectra. From the temporal kinetics, we show that carrier recombination reversibly unlocks the structural deformation at both Br and Pb sites. The comparison with the temperature-dependent XAS results rules out thermal effects as the primary source of distortion of the Pb-Br bonding motif during photoexcitation. Our work provides a comprehensive description of the CsPbBr3 perovskites photophysics, offering novel insights on the light-induced response of the system and its exceptional optoelectronic properties.

This report analyses the financial position of non-financial enterprises in the euro area, in particular the amount of external financing, the choice between debt and equity and the composition and maturity structure of debt. It aims at identifying the main features of the euro area, as well as the peculiarities that depend on the country of origin and the sector of activity. Attention is also devoted to assessing whether a country's institutional features are correlated with different financial structures by firms. In light of the particular interest in the access of small and medium-sized enterprises (SMEs) to financing, the report also analyses how financing patterns differ across large, medium-sized and small enterprises. Finally, the report discusses the recent trends observed in the corporate finance landscape of the euro area over the past few years. Although it is still too early to pass final judgement, vast structural changes are underway that could have already influenced in a positive way in the availability of external funds for firms. All in all, a comprehensive understanding of corporate finance in the euro area is important from a monetary policy perspective, given its impact on the transmission mechanism and for productivity and economic growth. Moreover, such an understanding is also relevant from a financial stability perspective. A first assessment is now possible eight years into the third stage of Economic and Monetary Union (EMU), given that sufficient data have been accumulated during this period. This assessment is particularly important as the introduction of the single currency has had significant structural effects on the working of financial markets, increasing their size and liquidity, and fostering cross-border competition. The data available for this report generally cover the period 1995-2005, and the cut-off date for the statistics included is 10 March 2007. JEL Classification: D92, G30, G10, O16, K40