Development of a novel polyamide-based agent to inhibit EVI1 function

The EVI1 gene at chromosome 3q26 is associated with acute myeloid leukemogenesis, due to both chromosomal rearrangement and to overexpression in the absence of rearrangement. Some rearrangements such as t(3;3) and inv(3) result in overexpression of EVI1 protein, while translocation t(3;21) yields an AML1-MDS1-EVI1 (AME) fusion protein. EVI1 possesses two zinc finger domains, an N-terminal domain with fingers 1–7, which binds to GACAAGATA, and a C-terminal domain (fingers 8–10) which binds GAAGATGAG. Inhibition of EVI1 function with a small molecule compound may provide a targeted therapy for EVI1-expressing leukemias. As a first step towards inhibiting the leukemogenic function of EVI1, we performed structure-function studies on both EVI1 and AME protein to determine what domains are critical for malignant transformation activity. Assays were Rat1 fibroblasts in a soft agar colony forming assay for EVI1; primary bone marrow cells in a serial replating assay for AME. Both assays revealed that mutation of arginine 205 in zinc finger 6 of EVI1, which completely abrogates sequencespecific DNA binding via the N-terminal zinc finger domain, resulted in complete loss of transforming activity; mutations in other domains, such as the C-terminal zinc finger domain, CtBP binding domain, and the domains of AML1 had less of an effect or no effect on transforming activity. In an effort to inhibit EVI1 leukemogenic function, we developed a polyamide, DH-IV-298, designed to block zinc fingers 1–7 binding to the GACAAGATA motif. DNAseI footprinting revealed a specific interaction between DH-IV-298 and the GACAAGATA motif; no significant interaction was observed elsewhere; a mismatch polyamide failed to footprint at equivalent concentrations; and DH-IV-298 failed to bind to a control DNA lacking the GACAAGATA motif. Electromobility shift assay showed that, at a 1:1 polyamide:DNA ratio, DH-IV-298 lowered EVI1:DNA affinity by over 98%, while mismatch was significantly less effective (74% reduction). To assess the effect of DH-IV-298 on EVI1 binding to DNA in vivo, we performed CAT reporter assays in a NIH-3T3-derived cell line with a chromosome-embedded tet-inducible EVI1-VP16 as well as a EVI1-responsive CAT reporter. Removal of tetracycline resulted in a four-fold increase in CAT activity that was completely blocked by DH-IV-298. The mismatch polyamide was significantly less effective than DH-IV-298. Further studies are being performed to assess the effect on endogenous gene expression, and on growth of leukemic cells that express EVI1. These studies provide evidence that a cell permeable small molecule compound may effectively block the activity of a leukemogenic transcription factor

Context Switching with Multiple Register Windows: A RISC Performance Study

Although previous studies have shown that a large file of overlapping register windows can greatly reduce procedure call/return overhead, the effects of register windows in a multiprogramming environment are poorly understood. This paper investigates the performance of multiprogrammed, reduced instruction set computers (RISCs) as a function of window management strategy. Using an analytic model that reflects context switch and procedure call overheads, we analyze the performance of simple, linearly self-recursive programs. For more complex programs, we present the results of a simulation study. These studies show that a simple strategy that saves all windows prior to a context switch, but restores only a single window following a context switch, performs near optimally

Landslide occurrence in the Blue River Drainage, Oregon

Rapid, shallow soil mass movements (landslides) are examined for a 6,000 ha managed forest area in the Oregon Western Cascades. Analysis of landslide occurrence considers the physical characteristics and frequency, the influence of clearcutting and road construction, and some resource impacts. Nonparametric statistical methods are employed to test the significance of the observed variations in landslide characteristics. Landslide size and site characteristics appear highly consistent. Fifty-five to eighty percent of all landslide length, width, depth, area, and volume measurements fall within the lower 15% of their respective dimension ranges. Landslides occur most frequently at slope angles of 300 - L00, in northern aspects (NW - NNE), and in smooth slope locations. Landslide occurrence does not vary significantly (c(= 0.05) with relative hillslope position. Clearcutting and road construction appear to strongly affect landslide frequency and location. Landslides occur 2k and 253 times more frequently (relative to forest rate) in clearcut and road areas, respectively. Significant variation in landslide geomorphic setting with land use suggests that clearcutting and road construction may increase the landslide susceptibility of hillslope nose and hollow locations. They do not influence landslide size, slope angle, slope aspect, or hillslope position. Resource impacts from landslides are varied. Although on-site disruption is generally substantial, total ground area affected by landslides is small (approximately 0.5%). Roads stand out as an important resource consideration because landslide frequency and the number of stream entries by landslides are significantly higher for road-related failures. Road location, drainage, and fill slope construction methods are the probable causes of this accelerated landslide activity

Implicit complexity for coinductive data: a characterization of corecurrence

We propose a framework for reasoning about programs that manipulate coinductive data as well as inductive data. Our approach is based on using equational programs, which support a seamless combination of computation and reasoning, and using productivity (fairness) as the fundamental assertion, rather than bi-simulation. The latter is expressible in terms of the former. As an application to this framework, we give an implicit characterization of corecurrence: a function is definable using corecurrence iff its productivity is provable using coinduction for formulas in which data-predicates do not occur negatively. This is an analog, albeit in weaker form, of a characterization of recurrence (i.e. primitive recursion) in [Leivant, Unipolar induction, TCS 318, 2004].Comment: In Proceedings DICE 2011, arXiv:1201.034

Increased plasma vaspin concentration in patients with sepsis: an exploratory examination

Introduction: Vaspin (visceral adipose tissue-derived serpin) was first described as an insulin-sensitizing adipose tissue hormone. Recently its anti-inflammatory function has been demonstrated. Since no appropriate data is available yet, we sought to investigate the plasma concentrations of vaspin in sepsis. Materials and methods: 57 patients in intensive care, fulfilling the ACCP/SCCM criteria for sepsis, were prospectively included in our exploratory study. The control group consisted of 48 critically ill patients, receiving intensive care after trauma or major surgery. Patients were matched by age, sex, weight and existence of diabetes before statistical analysis. Blood samples were collected on the day of diagnosis. Vaspin plasma concentrations were measured using a commercially available enzyme-linked immunosorbent assay. Results: Vaspin concentrations were significantly higher in septic patients compared to the control group (0.3 (0.1-0.4) ng/mL vs. 0.1 (0.0-0.3) ng/mL, respectively; P < 0.001). Vaspin concentration showed weak positive correlation with concentration of C-reactive protein (CRP) (r = 0.31, P = 0.002) as well as with SAPS II (r = 0.34, P = 0.002) and maximum of SOFA (r = 0.39, P < 0.001) scoring systems, as tested for the overall study population. Conclusion: In the sepsis group, vaspin plasma concentration was about three-fold as high as in the median surgical control group. We demonstrated a weak positive correlation between vaspin and CRP concentration, as well as with two scoring systems commonly used in intensive care settings. Although there seems to be some connection between vaspin and inflammation, its role in human sepsis needs to be evaluated further

Impact of EMA regulatory label changes on systemic diclofenac initiation, discontinuation, and switching to other pain medicines in Scotland, England, Denmark, and The Netherlands

Purpose: In June 2013 a European Medicines Agency referral procedure concluded that diclofenac was associated with an elevated risk of acute cardiovascular events and contraindications, warnings, and changes to the product information were implemented across the European Union. This study measured the impact of the regulatory action on the prescribing of systemic diclofenac in Denmark, The Netherlands, England, and Scotland. Methods: Quarterly time series analyses measuring diclofenac prescription initiation, discontinuation and switching to other systemic nonsteroidal anti-inflammatory (NSAIDs), topical NSAIDs, paracetamol, opioids, and other chronic pain medication in those who discontinued diclofenac. Absolute effects were estimated using interrupted time series regression. Results: Overall, diclofenac prescription initiations fell during the observation periods of all countries. Compared with Denmark where there appeared to be amore limited effect, the regulatory action was associated with significant immediate reductions in diclofenac initiation in The Netherlands (−0.42%, 95% CI, −0.66% to −0.18%), England (−0.09%, 95% CI, −0.11% to −0.08%), and Scotland (−0.67%, 95% CI, −0.79% to −0.55%); and falling trends in diclofenac initiation in the Netherlands (−0.03%, 95% CI, −0.06% to −0.01% per quarter) and Scotland (−0.04%, 95% CI, −0.05% to −0.02% per quarter). There was no significant impact on diclofenac discontinuation in any country. The regulatory action was associated with modest differences in switching to other pain medicines following diclofenac discontinuation. Conclusions: The regulatory action was associated with significant reductions in overall diclofenac initiation which varied by country and type of exposure. There was no impact on discontinuation and variable impact on switching

Changes in Black Carbon Deposition to Antarctica from Two Ice Core Records, A.D. 1850-2000

Continuous flow analysis was based on a steady sample flow and in-line detection of BC and other chemical substances as described in McConnell et al. (2007). In the cold room, previously cut one meter ice core sticks of 3x3cm, are melted continuously on a heated melter head specifically designed to eliminate contamination from the atmosphere or by the external parts of the ice. The melted ice from the most inner part of the ice stick is continuously pumped by a peristaltic pump and carried to a clean lab by Teflon lines. The recorded signal is continuous, integrating a sample volume of about 0.05 mL, for which the temporal resolution depends on the speed of melting, ice density and snow accumulation rate at the ice core drilling site. For annual accumulation derived from the WAIS and Law Dome ice cores, we assumed ~3.1 cm water equivalent uncertainty in each year's accumulation from short scale spatial variability (glaciological noise) which was determined from several measurements of annual accumulation in multiple parallel ice cores notably from the WAIS Divide ice core site (Banta et al., 2008) and from South Pole site (McConnell et al., 1997; McConnell et al., 2000). Refractory black carbon (rBC) concentrations were determined using the same method as in (Bisiaux et al., 2011) and adapted to continuous flow measurements as described by (McConnell et al., 2007). The technique uses a single particle intracavity laser induced incandescence photometer (SP2, Droplet Measurement Technologies, Boulder, Colorado) coupled to an ultrasonic nebulizer/desolvation (CETAC UT5000) Flow Injection Analysis (FIA). All analyses, sample preparation etc, were performed in a class 100 cleanroom using anti contamination "clean techniques". The samples were not acidified