3-O-Methylfunicone, a Selective Inhibitor of Mammalian Y-Family DNA Polymerases from an Australian Sea Salt Fungal Strain

We isolated a pol inhibitor from the cultured mycelia extract of a fungal strain isolated from natural salt from a sea salt pan in Australia, which was identified as 3-O-methylfunicone by spectroscopic analyses. This compound selectively inhibited the activities of mammalian Y-family DNA polymerases (pols) (i.e., pols η, ι and κ). Among these pols, human pol κ activity was most strongly inhibited, with an IC50 value of 12.5 μM. On the other hand, the compound barely influenced the activities of the other families of mammalian pols, such as A-family (i.e., pol γ), B-family (i.e., pols α, δ and ɛ) or X-family (i.e., pols β, λ and terminal deoxynucleotidyl transferase), and showed no effect on the activities of fish pol δ, plant pols, prokaryotic pols and other DNA metabolic enzymes, such as calf primase of pol α, human immunodeficiency virus type-1 (HIV-1) reverse transcriptase, human telomerase, T7 RNA polymerase, mouse IMP dehydrogenase (type II), human topoisomerases I and II, T4 polynucleotide kinase or bovine deoxyribonuclease I. This compound also suppressed the growth of two cultured human cancer cell lines, HCT116 (colon carcinoma cells) and HeLa (cervix carcinoma cells), and UV-treated HeLa cells exhibited lower clonogenic survival in the presence of inhibitor

Heat Capacity of Pd-Si, Ni-Si-B and Zr-Based Metallic Glasses

The specific heat of metallic glasses containing Si and B (Ni_Si_B_ and Pd_Si_) and Zr-based metallic glasses(Zr_Al_Cu_Ni_Co_, Zr_Al_Cu_ and Zr_Cu_) was measured in the temperature range 77-800 K using an a.c. calorimeter. Several exothermic and endothermic processes were observed correspondingly to the transformation sequences for complete crystallization of all the glasses. The structural relaxation process appears with a decrease in heat capacity. For Ni-Si-B and Pd-Si glasses an abrupt increase in the specific heat is observed at the glass transition temperature T_g. For Zr-based glasses, however, a monotonous increase in the specific heat is observed just below T_g. Then the specific heat makes a peak and decrease abruptly with increasing temperature. The height of the peak increases with heating rate

Chemical Bonding, Interfaces and Defects in Hafnium Oxide/Germanium Oxynitride Gate Stacks on Ge (100)

Correlations among interface properties and chemical bonding characteristics in HfO{sub 2}/GeO{sub x}N{sub y}/Ge MIS stacks were investigated using in-situ remote nitridation of the Ge (100) surface prior to HfO{sub 2} atomic layer deposition (ALD). Ultra thin ({approx}1.1 nm), thermally stable and aqueous etch-resistant GeO{sub x}N{sub y} interfaces layers that exhibited Ge core level photoelectron spectra (PES) similar to stoichiometric Ge{sub 3}N{sub 4} were synthesized. To evaluate GeO{sub x}N{sub y}/Ge interface defects, the density of interface states (D{sub it}) was extracted by the conductance method across the band gap. Forming gas annealed (FGA) samples exhibited substantially lower D{sub it} ({approx} 1 x 10{sup 12} cm{sup -2} eV{sup -1}) than did high vacuum annealed (HVA) and inert gas anneal (IGA) samples ({approx} 1x 10{sup 13} cm{sup -2} eV{sup -1}). Germanium core level photoelectron spectra from similar FGA-treated samples detected out-diffusion of germanium oxide to the HfO{sub 2} film surface and apparent modification of chemical bonding at the GeO{sub x}N{sub y}/Ge interface, which is related to the reduced D{sub it}

Gene Organization in Rice Revealed by Full-Length cDNA Mapping and Gene Expression Analysis through Microarray

Rice (Oryza sativa L.) is a model organism for the functional genomics of monocotyledonous plants since the genome size is considerably smaller than those of other monocotyledonous plants. Although highly accurate genome sequences of indica and japonica rice are available, additional resources such as full-length complementary DNA (FL-cDNA) sequences are also indispensable for comprehensive analyses of gene structure and function. We cross-referenced 28.5K individual loci in the rice genome defined by mapping of 578K FL-cDNA clones with the 56K loci predicted in the TIGR genome assembly. Based on the annotation status and the presence of corresponding cDNA clones, genes were classified into 23K annotated expressed (AE) genes, 33K annotated non-expressed (ANE) genes, and 5.5K non-annotated expressed (NAE) genes. We developed a 60mer oligo-array for analysis of gene expression from each locus. Analysis of gene structures and expression levels revealed that the general features of gene structure and expression of NAE and ANE genes were considerably different from those of AE genes. The results also suggested that the cloning efficiency of rice FL-cDNA is associated with the transcription activity of the corresponding genetic locus, although other factors may also have an effect. Comparison of the coverage of FL-cDNA among gene families suggested that FL-cDNA from genes encoding rice- or eukaryote-specific domains, and those involved in regulatory functions were difficult to produce in bacterial cells. Collectively, these results indicate that rice genes can be divided into distinct groups based on transcription activity and gene structure, and that the coverage bias of FL-cDNA clones exists due to the incompatibility of certain eukaryotic genes in bacteria

Tunneling Spectra of Skutterudite PrOs_4Sb_{12}

The tunnel conductance in normal-metal / insulator / PrOs$_4$Sb$_{12}$ junctions is theoretically studied, where skutterudite PrOs$_4$Sb$_{12}$ is considered to be an unconventional superconductor. The conductance are calculated for several pair potentials which have been proposed in recent works. The results show that the conductance is sensitive to the relation between the direction of electric currents and the position of point nodes. We also show that the conductance spectra often deviate from the shape of the bulk density of states and that the sub gap spectra have peak structures in the case of the spin-triplet pair potentials. The results indicate that the tunnel conductance is a useful tool to obtain an information of the pairing symmetry.Comment: 9 page

An Econometric Analysis of Insurance Markets with Separate Identification for Moral Hazard and Selection

This paper proposes a simple microeconometric framework that can separately identify moral hazard and selection problems in insurance markets. Our econometric model is equivalent to the approach that is utilized for entry game analyses. We employ a Bayesian estimation approach that avoids a partial identification problem. Due to the standard identification, we propose a statistical model selection method to detect an information structure that consumers face. Our method is applied to the dental insurance market in the United States. In this market, we find not only standard moral hazard but also advantageous selection, which has an intuitive interpretation in the context of dental insurance

Duopoly in the Japanese Airline Market : Bayesian Estimation for the Entry Game

This paper provides an econometric analysis on a duopoly game in the Japanese domestic airline market. We establish a novel Bayesian estimation approach for the entry game, which is free from the conventional identification problem and thus allows the incorporation of flexible inference techniques. We find asymmetric strategic interactions between Japanese firms, which implies that competition will still be influenced by the former regulation regime. Furthermore, our prediction analysis indicates that the new Shizuoka airport will suffer from a lack of demand.Revised version of CIRJE-F-556 (2008); revised as CIRJE-F-797 (2011)

An Econometric Analysis of Insurance Markets with Separate Identification for Moral Hazard and Selection Problems

This paper proposes a simple econometric framework that can identify moral hazard and selection problems separately in insurance markets. Although our methodology requires behavioral assumptions on the consumer\u27s optimization, we show that these assumptions are necessary for the separate identification of the two sources of information asymmetry. Our method is applied to the dental insurance market in the United States. In addition to standard moral hazard, we find advantageous selection, which is not detected by a conventional methodology.本文フィルはリンク先を参照のこ