Product Distributions In The CO2-NH3-H2O System From Liquid Conductivity Measurements

The objective of this work was to illustrate how liquid conductivity measurements could be used to provide information about the extent of ionization and the amounts of the various ionic products that are formed in the liquid phase in the CO2-NH3-H2O system. To accomplish this, pressures and liquid-phase conductivities for the CO2-NH3-H2O system were measured at 25 °C and over a range of pressures and concentrations. In order to acquire the desired information from bulk conductivity measurements, calibration curves were established from measurements with several potassium salts. These curves, in conjunction with the experimental conductivity, allowed the (approximate) determination of both the concentration of the NH4+ ion and the distribution of CO2 between singly and doubly charged ions. Comparison to the predictions of two existing models for the CO2-NH3-H2O system showed that these models underpredicted the concentration of the ammonium ion. This suggests that correct predictions of the vapor-phase compositions and pressures by a solution model do not guarantee that the description of the liquid phase is correct. © 1992, American Chemical Society. All rights reserved

Enzymatic Characterization of ER Stress-Dependent Kinase, PERK, and Development of a High-Throughput Assay for Identification of PERK Inhibitors

PERK is serine/threonine kinase localized to the endoplasmic reticulum (ER) membrane. PERK is activated and contributes to cell survival in response to a variety of physiological stresses that affect protein quality control in the ER, such as hypoxia, glucose depravation, increased lipid biosynthesis, and increased protein translation. Pro-survival functions of PERK are triggered by such stresses, suggesting that development of small-molecule inhibitors of PERK may be efficacious in a variety of disease scenarios. Hence, we have conducted a detailed enzymatic characterization of the PERK kinase to develop a high-throughput-screening assay (HTS) that will permit the identification of small-molecule PERK inhibitors. In addition to establishing the Km of PERK for both its primary substrate, eIF2?, and for adenosine triphosphate, further mechanistic studies revealed that PERK targets its substrate via either a random/steady-state ordered mechanism. For HTS, we developed a time-resolved fluorescence resonance energy transfer–based assay that yielded a robust Z? factor and percent coefficient of variation value, enabling the successful screening of 79,552 compounds. This approach yielded one compound that exhibited good in vitro and cellular activity. These results demonstrate the validity of this screen and represent starting points for drug discovery efforts

Lowering of amyloid beta peptide production with a small molecule inhibitor of amyloid-? precursor protein dimerization

The amyloid ? precursor protein (APP) is a single-pass transmembrane glycoprotein that is ubiquitously expressed in many cell types, including neurons. Amyloidogenic processing of APP by ?- and ?-secretases leads to the production of amyloid-? (A?) peptides that can oligomerize and aggregate into amyloid plaques, a characteristic hallmark of Alzheimer’s disease (AD) brains. Multiple reports suggest that dimerization of APP may play a role in A? production; however, it is not yet clear whether APP dimers increase or decrease A? and the mechanism is not fully understood. To better understand the relationship between APP dimerization and production of A?, a high throughput screen for small molecule modulators of APP dimerization was conducted using APP-Firefly luciferase enzyme complementation to detect APP dimerization. Selected modulators identified from a compound library of 77,440 compounds were tested for their effects on A? generation. Two molecules that inhibited APP dimerization produced a reduction in A? levels as measured by ELISA. The inhibitors did not change sAPP? or ?-CTF levels, but lowered sAPP? levels, suggesting that blocking the dimerization is preventing the cleavage by ?-secretase in the amyloidogenic processing of APP. To our knowledge, this is the first High Throughput Screen (HTS) effort to identify small molecule modulators of APP dimerization. Inhibition of APP dimerization has previously been suggested as a therapeutic target in AD. The findings reported here further support that modulation of APP dimerization may be a viable means of reducing the production of A?

Perinatal Exposure to Low Levels of the Environmental Antiandrogen Vinclozolin Alters Sex-Differentiated Social Play and Sexual Behaviors in the Rat

In this study we examined the effects of exposure to the antiandrogenic fungicide vinclozolin (Vz) on the development of two sex-differentiated behaviors that are organized by the perinatal actions of androgens. Pregnant Long-Evans rats were administered a daily oral dose of 0, 1.5, 3, 6, or 12 mg/kg Vz from the 14th day of gestation through postnatal day (PND)3. The social play behavior of juvenile offspring was examined on PND22 and again on PND34 during play sessions with a same-sex littermate. After they reached adulthood, the male offspring were examined with the ex copula penile reflex procedure to assess erectile function. Vz did not produce any gross maternal or neonatal toxicity, nor did it reduce the anogenital distance in male pups. We observed no effects of Vz on play behavior on PND22. However, the 12-mg/kg Vz dose significantly increased play behavior in the male offspring on PND34 compared with controls. The most dramatic increases were seen with the nape contact and pounce behavior components of play. The Vz effect was more pronounced in male than in female offspring. As adults, male offspring showed a significant reduction of erections at all dose levels during the ex copula penile reflex tests. The 12-mg/kg dose was also associated with an increase in seminal emissions. These effects demonstrate that perinatal Vz disrupts the development of androgen-mediated behavioral functions at exposure levels that do not produce obvious structural changes or weight reductions in androgen-sensitive reproductive organs

UBVRI Light Curves of 44 Type Ia Supernovae

We present UBVRI photometry of 44 type-Ia supernovae (SN Ia) observed from 1997 to 2001 as part of a continuing monitoring campaign at the Fred Lawrence Whipple Observatory of the Harvard-Smithsonian Center for Astrophysics. The data set comprises 2190 observations and is the largest homogeneously observed and reduced sample of SN Ia to date, nearly doubling the number of well-observed, nearby SN Ia with published multicolor CCD light curves. The large sample of U-band photometry is a unique addition, with important connections to SN Ia observed at high redshift. The decline rate of SN Ia U-band light curves correlates well with the decline rate in other bands, as does the U-B color at maximum light. However, the U-band peak magnitudes show an increased dispersion relative to other bands even after accounting for extinction and decline rate, amounting to an additional ~40% intrinsic scatter compared to B-band.Comment: 84 authors, 71 pages, 51 tables, 10 figures. Accepted for publication in the Astronomical Journal. Version with high-res figures and electronic data at http://astron.berkeley.edu/~saurabh/cfa2snIa

Brief Report: Comprehensive Clinicogenomic Profiling of Small Cell Transformation From EGFR-Mutant NSCLC Informs Potential Therapeutic Targets

INTRODUCTION: NSCLC transformation to SCLC has been best characterized with METHODS: In this study, we conducted a single-center retrospective analysis of clinical and genomic characteristics of patients with RESULTS: A total of 34 patients were identified in our study. Median age at initial diagnosis was 58, and median time to SCLC transformation was 24.2 months. 68% were female and 82% were never smokers. 79% of patients were diagnosed as stage IV disease, and over half had brain metastases at baseline. Median overall survival of the entire cohort was 38.3 months from initial diagnoses and 12.4 months from time of SCLC transformation. Most patients harbored CONCLUSIONS: SCLC transformation is a potential treatment resistance mechanism in driver-mutant NSCLC. In our cohort of 3

Tumor- and Circulating-Free DNA Methylation Identifies Clinically Relevant Small Cell Lung Cancer Subtypes

Small cell lung cancer (SCLC) is an aggressive malignancy composed of distinct transcriptional subtypes, but implementing subtyping in the clinic has remained challenging, particularly due to limited tissue availability. Given the known epigenetic regulation of critical SCLC transcriptional programs, we hypothesized that subtype-specific patterns of DNA methylation could be detected in tumor or blood from SCLC patients. Using genomic-wide reduced-representation bisulfite sequencing (RRBS) in two cohorts totaling 179 SCLC patients and using machine learning approaches, we report a highly accurate DNA methylation-based classifier (SCLC-DMC) that can distinguish SCLC subtypes. We further adjust the classifier for circulating-free DNA (cfDNA) to subtype SCLC from plasma. Using the cfDNA classifier (cfDMC), we demonstrate that SCLC phenotypes can evolve during disease progression, highlighting the need for longitudinal tracking of SCLC during clinical treatment. These data establish that tumor and cfDNA methylation can be used to identify SCLC subtypes and might guide precision SCLC therapy

The LatMix summer campaign : submesoscale stirring in the upper ocean

Author Posting. © American Meteorological Society, 2015. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 96 (2015): 1257–1279, doi:10.1175/BAMS-D-14-00015.1.Lateral stirring is a basic oceanographic phenomenon affecting the distribution of physical, chemical, and biological fields. Eddy stirring at scales on the order of 100 km (the mesoscale) is fairly well understood and explicitly represented in modern eddy-resolving numerical models of global ocean circulation. The same cannot be said for smaller-scale stirring processes. Here, the authors describe a major oceanographic field experiment aimed at observing and understanding the processes responsible for stirring at scales of 0.1–10 km. Stirring processes of varying intensity were studied in the Sargasso Sea eddy field approximately 250 km southeast of Cape Hatteras. Lateral variability of water-mass properties, the distribution of microscale turbulence, and the evolution of several patches of inert dye were studied with an array of shipboard, autonomous, and airborne instruments. Observations were made at two sites, characterized by weak and moderate background mesoscale straining, to contrast different regimes of lateral stirring. Analyses to date suggest that, in both cases, the lateral dispersion of natural and deliberately released tracers was O(1) m2 s–1 as found elsewhere, which is faster than might be expected from traditional shear dispersion by persistent mesoscale flow and linear internal waves. These findings point to the possible importance of kilometer-scale stirring by submesoscale eddies and nonlinear internal-wave processes or the need to modify the traditional shear-dispersion paradigm to include higher-order effects. A unique aspect of the Scalable Lateral Mixing and Coherent Turbulence (LatMix) field experiment is the combination of direct measurements of dye dispersion with the concurrent multiscale hydrographic and turbulence observations, enabling evaluation of the underlying mechanisms responsible for the observed dispersion at a new level.The bulk of this work was funded under the Scalable Lateral Mixing and Coherent Turbulence Departmental Research Initiative and the Physical Oceanography Program. The dye experiments were supported jointly by the Office of Naval Research and the National Science Foundation Physical Oceanography Program (Grants OCE-0751653 and OCE-0751734).2016-02-0

Data-analysis strategies for image-based cell profiling

Image-based cell profiling is a high-throughput strategy for the quantification of phenotypic differences among a variety of cell populations. It paves the way to studying biological systems on a large scale by using chemical and genetic perturbations. The general workflow for this technology involves image acquisition with high-throughput microscopy systems and subsequent image processing and analysis. Here, we introduce the steps required to create high-quality image-based (i.e., morphological) profiles from a collection of microscopy images. We recommend techniques that have proven useful in each stage of the data analysis process, on the basis of the experience of 20 laboratories worldwide that are refining their image-based cell-profiling methodologies in pursuit of biological discovery. The recommended techniques cover alternatives that may suit various biological goals, experimental designs, and laboratories' preferences.Peer reviewe

Common variants at theCHEK2gene locus and risk of epithelial ovarian cancer

Genome-wide association studies have identified 20 genomic regions associated with risk of epithelial ovarian cancer (EOC), but many additional risk variants may exist. Here, we evaluated associations between common genetic variants [single nucleotide polymorphisms (SNPs) and indels] in DNA repair genes and EOC risk. We genotyped 2896 common variants at 143 gene loci in DNA samples from 15 397 patients with invasive EOC and controls. We found evidence of associations with EOC risk for variants at FANCA, EXO1, E2F4, E2F2, CREB5 and CHEK2 genes (P ≤ 0.001). The strongest risk association was for CHEK2 SNP rs17507066 with serous EOC (P = 4.74 x 10(-7)). Additional genotyping and imputation of genotypes from the 1000 genomes project identified a slightly more significant association for CHEK2 SNP rs6005807 (r (2) with rs17507066 = 0.84, odds ratio (OR) 1.17, 95% CI 1.11-1.24, P = 1.1×10(-7)). We identified 293 variants in the region with likelihood ratios of less than 1:100 for representing the causal variant. Functional annotation identified 25 candidate SNPs that alter transcription factor binding sites within regulatory elements active in EOC precursor tissues. In The Cancer Genome Atlas dataset, CHEK2 gene expression was significantly higher in primary EOCs compared to normal fallopian tube tissues (P = 3.72×10(-8)). We also identified an association between genotypes of the candidate causal SNP rs12166475 (r (2) = 0.99 with rs6005807) and CHEK2 expression (P = 2.70×10(-8)). These data suggest that common variants at 22q12.1 are associated with risk of serous EOC and CHEK2 as a plausible target susceptibility gene.Other Research Uni