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Sample records for 4a 4b 4c

  1. Association between C4, C4A, and C4B copy number variations and susceptibility to autoimmune diseases: a meta-analysis

    PubMed Central

    Li, Na; Zhang, Jun; Liao, Dan; Yang, Lu; Wang, Yingxiong; Hou, Shengping

    2017-01-01

    Although several studies have investigated the association between C4, C4A, and C4B gene copy number variations (CNVs) and susceptibility to autoimmune diseases, the results remain inconsistency for those diseases. Thus, in this study, a comprehensive meta-analysis was conducted to assess the role of C4, C4A, and C4B CNVs in autoimmune diseases in different ethnic groups. A total of 16 case-control studies described in 12 articles (8663 cases and 11099 controls) were included in this study. The pooled analyses showed that a low C4 gene copy number (GCN) (<4) was treated as a significant risk factor (odds ratio [OR] = 1.46, 95% confidence interval [CI] = 1.19–1.78) for autoimmune diseases compared with a higher GCN (>4). The pooled statistical results revealed that low C4 (<4) and low C4A (<2) GCNs could be risk factors for systemic lupus erythematosus (SLE) in Caucasian populations. Additionally, the correlation between C4B CNVs and all type of autoimmune diseases could not be confirmed by the current meta-analysis (OR = 1.07, 95% CI = 0.93–1.24). These data suggest that deficiency or absence of C4 and C4A CNVs may cause susceptibility to SLE. PMID:28205620

  2. Complement components C2, C3, and C4 (C4A and C4B) and BF polymorphisms in populations of the Indian subcontinent.

    PubMed

    Ad'hiah, A H; Papiha, S S

    1996-10-01

    Genetic polymorphisms of the complement components (five loci: C2, C3, C4A, C4B, and BF) have been investigated in the Telugu-speaking Hindu population of Hyderabad, Andhra Pradesh, India, and the Bangali-speaking Muslim population of Dacca, Bangladesh. The available data are compared to understand the genetic variation of complement components in populations of the Indian subcontinent. The C3*F and BF*F alleles show wide frequency variations in different ethnic groups of India. The range of variation in the C3*F allele is intermediate between European whites and southeast Asian populations, whereas the BF*F allele places the Indian frequencies between European whites and African blacks. This is the first population study to investigate the C2 and C4 (C4A and C4B) polymorphisms in two distinct groups of the Indian subcontinent. For the C2 polymorphism only the C2*B variant allele was observed, and its frequency was slightly higher than in European populations. In both populations the C4A and C4B loci were highly polymorphic, with a high frequency of the null alleles C4A*QO and C4B*QO, which may account for the greater susceptibility to certain autoimmune diseases in populations of South Asia.

  3. Conspirators in a capital crime: co-deletion of p18INK4c and p16INK4a/p14ARF/p15INK4b in glioblastoma multiforme.

    PubMed

    Solomon, David A; Kim, Jung-Sik; Jean, Walter; Waldman, Todd

    2008-11-01

    Glioblastoma multiforme (GBM) is one of the most dreaded cancer diagnoses due to its poor prognosis and the limited treatment options. Homozygous deletion of the p16(INK4a)/p14(ARF)/p15(INK4b) locus is among the most common genetic alterations in GBM. Two recent studies have shown that deletion and mutation of another INK4 family member, p18(INK4c), also drives the pathogenesis of GBM. This minireview will discuss the known roles for p18(INK4c) in the initiation and progression of cancer and suggest opportunities for future studies.

  4. Results of hydrologic tests and water-chemistry analyses, wells H-4A, H-4B, and H-4C, at the proposed waste isolation pilot plant site, southeastern New Mexico

    USGS Publications Warehouse

    Mercer, Jerry W.; Davis, Paul; Dennehy, K.F.; Goetz, C.L.

    1981-01-01

    Data were collected during hydrologic testing at wells H-4A, H-4B, and H-4C in the southern part of the proposed Waste Isolation Pilot Plant site in southeastern New Mexico. The three water-bearing zones tested, the Magenta and Culebra Dolomite Members of the Rustler Formation and the Rustler Formation-Salado Formation contact, yield water to wells at rates less than 0.9 gallon per minute. Throughout the testing, water-pressure response in the tested zone was monitored by a pressure transducer system. Shut-in and slug tests were conducted to acquire the data from which the following values were derived. Calculated transmissivities for the Magenta, Culebra and the Rustler-Salado contact at wells H-4A, H-4B, and H-4C were 0.06, 0.9, and 0.0006 foot squared per day respectively. Water samples from the Magenta and Culebra had dissolved-solids concentrations of 22,300 and 18,100 milligrams per liter, respectively. The major chemical constituents of ground-water samples from these two zones were sodium, chloride, and sulfate. Water samples from the Rustler-Salado contact had a dissolved-solids concentration of 322,000 milligrams per liter and magnesium, sodium, and chloride were the major constituents. Radium-226, a naturally occurring radioactive element, was present in samples from all three zones. (USGS)

  5. Characterization of Dengue Virus NS4A and NS4B Protein Interaction

    PubMed Central

    Zou, Jing; Xie, Xuping; Wang, Qing-Yin; Dong, Hongping; Lee, Michelle Yueqi; Kang, Congbao

    2015-01-01

    ABSTRACT Flavivirus replication is mediated by a membrane-associated replication complex where viral membrane proteins NS2A, NS2B, NS4A, and NS4B serve as the scaffold for the replication complex formation. Here, we used dengue virus serotype 2 (DENV-2) as a model to characterize viral NS4A-NS4B interaction. NS4A interacts with NS4B in virus-infected cells and in cells transiently expressing NS4A and NS4B in the absence of other viral proteins. Recombinant NS4A and NS4B proteins directly bind to each other with an estimated Kd (dissociation constant) of 50 nM. Amino acids 40 to 76 (spanning the first transmembrane domain, consisting of amino acids 50 to 73) of NS4A and amino acids 84 to 146 (also spanning the first transmembrane domain, consisting of amino acids 101 to 129) of NS4B are the determinants for NS4A-NS4B interaction. Nuclear magnetic resonance (NMR) analysis suggests that NS4A residues 17 to 80 form two amphipathic helices (helix α1, comprised of residues 17 to 32, and helix α2, comprised of residues 40 to 47) that associate with the cytosolic side of endoplasmic reticulum (ER) membrane and helix α3 (residues 52 to 75) that transverses the ER membrane. In addition, NMR analysis identified NS4A residues that may participate in the NS4A-NS4B interaction. Amino acid substitution of these NS4A residues exhibited distinct effects on viral replication. Three of the four NS4A mutations (L48A, T54A, and L60A) that affected the NS4A-NS4B interaction abolished or severely reduced viral replication; in contrast, two NS4A mutations (F71A and G75A) that did not affect NS4A-NS4B interaction had marginal effects on viral replication, demonstrating the biological relevance of the NS4A-NS4B interaction to DENV-2 replication. Taken together, the study has provided experimental evidence to argue that blocking the NS4A-NS4B interaction could be a potential antiviral approach. IMPORTANCE Flavivirus NS4A and NS4B proteins are essential components of the ER membrane

  6. Monoclonal antipeptide antibodies against amino acid residues 1101-1106 of human C4 distinguish C4A from C4B.

    PubMed

    Reilly, B D; Levine, P; Rothbard, J; Skanes, V M

    1991-01-01

    Comparison of amino acid sequences of the alpha-chain fragment of human C4, C4d, has shown C4A- and C4B-specific sequences at residues 1101-1106 in which the aspartic acid-histidine substitution at position 1106 may be related to the amide and ester bond forming properties of these molecules. Peptides containing twelve amino acid residues of the C4A- or C4B-specific sequences were synthesized and injected into female Balb/c mice. Serum from 2 mice, one immunized with the C4A-specific peptide and the other with the C4B-specific peptide, gave strong isotype-specific responses in an enzyme-linked immunosorbent assay against affinity-purified C4A3 and C4B2B1. Spleen cells from these mice were fused with the mouse myeloma SP2/0-Ag 14, and two cloned cell lines, AII-1 and BII-1, were established from hybrids. Enzyme-linked immunosorbent assay and western blotting of monoclonal antibodies AII-1 and BII-1 show that the former reacts with the C4A but not with the C4B alpha-chain and the latter with C4B but not with the C4A alpha-chain. Furthermore, immunoblotting of C4 allelic variants showed that AII-1 reacted with all C4A allotypes tested, including A6, A4, A3 and A2, whereas BII-1 reacted with all C4B allotypes tested, including B5, B3, B2, and B1.

  7. Specificity of the hepatitis C virus NS3 serine protease: effects of substitutions at the 3/4A, 4A/4B, 4B/5A, and 5A/5B cleavage sites on polyprotein processing.

    PubMed Central

    Kolykhalov, A A; Agapov, E V; Rice, C M

    1994-01-01

    Cleavage at four sites (3/4A, 4A/4B, 4B/5A, and 5A/5B) in the hepatitis C virus polyprotein requires a viral serine protease activity residing in the N-terminal one-third of the NS3 protein. Sequence comparison of the residues flanking these cleavage sites reveals conserved features including an acidic residue (Asp or Glu) at the P6 position, a Cys or Thr residue at the P1 position, and a Ser or Ala residue at the P1' position. In this study, we used site-directed mutagenesis to assess the importance of these and other residues for NS3 protease-dependent cleavages. Substitutions at the P7 to P2' positions of the 4A/4B site had varied effects on cleavage efficiency. Only Arg at the P1 position or Pro at P1' substantially blocked processing at this site. Leu was tolerated at the P1 position, whereas five other substitutions allowed various degrees of cleavage. Substitutions with positively charged or other hydrophilic residues at the P7, P3, P2, and P2' positions did not reduce cleavage efficiency. Five substitutions examined at the P6 position allowed complete cleavage, demonstrating that an acidic residue at this position is not essential. Parallel results were obtained with substrates containing an active NS3 protease domain in cis or when the protease domain was supplied in trans. Selected substitutions blocking or inhibiting cleavage at the 4A/4B site were also examined at the 3/4A, 4B/5A, and 5A/5B sites. For a given substitution, a site-dependent gradient in the degree of inhibition was observed, with a 3/4A site being least sensitive to mutagenesis, followed by the 4A/4B, 4B/5A, and 5A/5B sites. In most cases, mutations abolishing cleavage at one site did not affect processing at the other serine protease-dependent sites. However, mutations at the 3/4A site which inhibited cleavage also interfered with processing at the 4B/5A site. Finally, during the course of these studies an additional NS3 protease-dependent cleavage site has been identified in the NS4B

  8. The gene history of zebrafish tlr4a and tlr4b is predictive of their divergent functions.

    PubMed

    Sullivan, Con; Charette, Jeremy; Catchen, Julian; Lage, Christopher R; Giasson, Gregory; Postlethwait, John H; Millard, Paul J; Kim, Carol H

    2009-11-01

    Mammalian immune responses to LPS exposure are typified by the robust induction of NF-kappaB and IFN-beta responses largely mediated by TLR4 signal transduction pathways. In contrast to mammals, Tlr4 signal transduction pathways in nontetrapods are not well understood. Comprehensive syntenic and phylogenetic analyses support our hypothesis that zebrafish tlr4a and tlr4b genes are paralogous rather than orthologous to human TLR4. Furthermore, we provide evidence to support our assertion that the in vivo responsiveness of zebrafish to LPS exposure is not mediated by Tlr4a and Tlr4b paralogs because they fail to respond to LPS stimulation in vitro. Zebrafish Tlr4a and Tlr4b paralogs were also unresponsive to heat-killed Escherichia coli and Legionella pneumophila. Using chimeric molecules in which portions of the zebrafish Tlr4 proteins were fused to portions of the mouse TLR4 protein, we show that the lack of responsiveness to LPS was most likely due to the inability of the extracellular portions of zebrafish Tlr4a and Tlr4b to recognize the molecule, rather than to changes in their capacities to transduce signals through their Toll/IL-1 receptor (TIR) domains. Taken together, these findings strongly support the notion that zebrafish tlr4a and tlr4b paralogs have evolved to provide alternative ligand specificities to the Tlr immune defense system in this species. These data demonstrate that intensive examination of gene histories when describing the Tlr proteins of basally diverging vertebrates is required to obtain fuller appreciation of the evolution of their function. These studies provide the first evidence for the functional evolution of a novel Tlr.

  9. Distinct and overlapping functions of the cullin E3 ligase scaffolding proteins CUL4A and CUL4B

    PubMed Central

    Hannah, Jeffrey

    2016-01-01

    The cullin 4 subfamily of genes includes CUL4A and CUL4B, which share a mostly identical amino acid sequence aside from the elongated N-terminal region in CUL4B. Both act as scaffolding proteins for modular cullin RING ligase 4 (CRL4) complexes which promote the ubiquitination of a variety of substrates. CRL4 function is vital to cells as loss of both genes or their shared substrate adaptor protein DDB1 halts proliferation and eventually leads to cell death. Due to their high structural similarity, CUL4A and CUL4B share a substantial overlap in function. However, in some cases, differences in subcellular localization, spatiotemporal expression patterns and stress-inducibility preclude functional compensation. In this review, we highlight the most essential functions of the CUL4 genes in: DNA repair and replication, chromatin-remodeling, cell cycle regulation, embryogenesis, hematopoiesis and spermatogenesis. CUL4 genes are also clinically relevant as dysregulation can contribute to the onset of cancer and CRL4 complexes are often hijacked by certain viruses to promote viral replication and survival. Also, mutations in CUL4B have been implicated in a subset of patients suffering from syndromic X-linked intellectual disability (AKA mental retardation). Interestingly, the antitumor effects of immunomodulatory drugs are caused by their binding to the CRL4CRBN complex and re-directing the E3 ligase towards the Ikaros transcription factors IKZF1 and IKZF3. Because of their influence over key cellular functions and relevance to human disease, CRL4s are considered promising targets for therapeutic intervention. PMID:26344709

  10. Cell surface trafficking of TLR1 is differentially regulated by the chaperones PRAT4A and PRAT4B.

    PubMed

    Hart, Bryan E; Tapping, Richard I

    2012-05-11

    The subcellular localization of Toll-like receptors (TLRs) is critical to their ability to function as innate immune sensors of microbial infection. We previously reported that an I602S polymorphism of human TLR1 is associated with aberrant trafficking of the receptor to the cell surface, loss of responses to TLR1 agonists, and differential susceptibility to diseases caused by pathogenic mycobacteria. Through an extensive analysis of receptor deletion and point mutants we have discovered that position 602 resides within a short 6 amino acid cytoplasmic region that is required for TLR1 surface expression. This short trafficking motif, in conjunction with the adjacent transmembrane domain, is sufficient to direct TLR1 to the cell surface. A serine at position 602 interrupts this trafficking motif and prevents cell surface expression of TLR1. Additionally, we have found that ER-resident TLR chaperones, PRAT4A and PRAT4B, act as positive and negative regulators of TLR1 surface trafficking, respectively. Importantly, either over-expression of PRAT4A or knock-down of PRAT4B rescues cell surface expression of the TLR1 602S variant. We also report that IFN-γ treatment of primary human monocytes derived from homozygous 602S individuals rescues TLR1 cell surface trafficking and cellular responses to soluble agonists. This event appears to be mediated by PRAT4A whose expression is strongly induced in human monocytes by IFN-γ. Collectively, these results provide a mechanism for the differential trafficking of TLR1 I602S variants, and highlight the distinct roles for PRAT4A and PRAT4B in the regulation of TLR1 surface expression.

  11. Cleavage at a novel site in the NS4A region by the yellow fever virus NS2B-3 proteinase is a prerequisite for processing at the downstream 4A/4B signalase site.

    PubMed Central

    Lin, C; Amberg, S M; Chambers, T J; Rice, C M

    1993-01-01

    Flavivirus proteins are produced by co- and posttranslational proteolytic processing of a large polyprotein by both host- and virus-encoded proteinases. The viral serine proteinase, which consists of NS2B and NS3, is responsible for cleavage of at least four dibasic sites (2A/2B, 2B/3, 3/4A, and 4B/5) in the nonstructural region. Since the amino acid sequence preceding NS4B shares characteristics with signal peptides used for translocation of nascent polypeptides into the lumen of the endoplasmic reticulum, it has been proposed that cleavage at the 4A/4B site is mediated by a cellular signal peptidase. In this report, cell-free translation and in vivo transient expression assays were used to study processing in the NS4 region of the yellow fever virus polyprotein. With a construct which contained NS4B preceded by 17 residues constituting the putative signal peptide (sig4B), membrane-dependent cleavage at the 4A/4B site was demonstrated in vitro. Surprisingly, processing of NS4A-4B was not observed in cell-free translation studies, and in vivo expression of several yellow fever virus polyproteins revealed that the 4A/4B cleavage occurred only during coexpression of NS2B and the proteinase domain of NS3. Examination of mutant derivatives of the NS3 proteinase domain demonstrated that cleavage at the 4A/4B site correlated with expression of an active NS2B-3 proteinase. From these results, we propose a model in which the signalase cleavage generating the N terminus of NS4B requires a prior NS2B-3 proteinase-mediated cleavage at a novel site (called the 4A/2K site) which is conserved among flaviviruses and located 23 residues upstream of the signalase site. In support of this model, mutations at the 4A/4B signalase site did not eliminate processing in the NS4 region. In contrast, substitutions at the 4A/2K site, which were engineered to block NS2B-3 proteinase-mediated cleavage, eliminated signalase cleavage at the 4A/4B site. In addition, the size of the 3(502)-4A

  12. KDM4B and KDM4A promote endometrial cancer progression by regulating androgen receptor, c-myc, and p27kip1

    PubMed Central

    Kwan, Suet-Ying; Chen, Limo; Chen, Jin-Hong; Ying, Zuo-Lin; Zhou, Ye; Gu, Wei; Wang, Li-Hua; Cheng, Wei-Wei; Zeng, Jianfang; Wan, Xiao-Ping; Mok, Samuel C.; Wong, Kwong-Kwok; Bao, Wei

    2015-01-01

    Epidemiological evidence suggests that elevated androgen levels and genetic variation related to the androgen receptor (AR) increase the risk of endometrial cancer (EC). However, the role of AR in EC is poorly understood. We report that two members of the histone demethylase KDM4 family act as major regulators of AR transcriptional activityin EC. In the MFE-296 cell line, KDM4B and AR upregulate c-myc expression, while in AN3CA cells KDM4A and AR downregulate p27kip1. Additionally, KDM4B expression is positively correlated with AR expression in EC cell lines with high baseline AR expression, while KDM4A and AR expression are positively correlated in low-AR cell lines. In clinical specimens, both KDM4B and KDM4A expression are significantly higher in EC tissues than that in normal endometrium. Finally, patients with alterations in AR, KDM4B, KDM4A, and c-myc have poor overall and disease-free survival rates. Together, these findings demonstrate that KDM4B and KDM4A promote EC progression by regulating AR activity. PMID:26397136

  13. Coriolis Interactions in the nu2, nu4a, nu4b, and nu3a States of Phosphine-d1

    PubMed

    Kshirsagar; Job

    1997-10-01

    Spectra of the nu4a (HPH bend) and nu4b (HPD bend) bands of the PH2D molecule have been recorded and analyzed. The Coriolis interactions between the two states as well as the various Coriolis interactions of the nu4a and nu4b states with the nu2 state have been included in the analysis. Several new assignments of transitions which occur with enhanced intensity in the nu2 band also have been made. The parameters of the nu4a and nu4b states, improved parameters of the nu2 state, and the interaction parameters have been determined. The data on the nu3a band of PH2D have been reanalyzed by taking into account the b-axis Coriolis interaction of the nu3a state with the 2nu2 state. Copyright 1997 Academic Press. Copyright 1997Academic Press

  14. Roles of p15Ink4b and p16Ink4a in myeloid differentiation and RUNX1-ETO-associated acute myeloid leukemia

    PubMed Central

    Ko, Rose M.; Kim, Hyung-Gyoon; Wolff, Linda; Klug, Christopher A.

    2008-01-01

    Inactivation of p15Ink4b expression by promoter hypermethylation occurs in up to 80% of acute myeloid leukemia (AML) cases and is particularly common in the FAB-M2 subtype of AML, which is characterized by the presence of the RUNX1-ETO translocation in 40% of cases. To establish whether the loss of p15Ink4b contributes to AML progression in association with RUNX1-ETO, we have expressed the RUNX1-ETO fusion protein from a retroviral vector in hematopoietic progenitor cells isolated from wild-type, p15Ink4b or p16Ink4a knockout bone marrow. Analysis of lethally irradiated recipient mice reconstituted with RUNX1-ETO-expressing cells showed that neither p15Ink4b or p16Ink4a loss significantly accelerated disease progression over the time period of one year post-transplantation. Loss of p15Ink4b alone resulted in increased myeloid progenitor cell frequencies in bone marrow by 10 months post-transplant and a 19-fold increase in the frequency of Lin-c-Kit+Sca-1+ (LKS) cells that was not associated with expansion of long-term reconstituting HSC. These results strongly suggest that p15Ink4b loss must be accompanied by additional oncogenic changes for RUNX1-ETO-associated AML to develop. PMID:18037485

  15. eIF4B stimulates eIF4A ATPase and unwinding activities by direct interaction through its 7-repeats region.

    PubMed

    Andreou, Alexandra Zoi; Harms, Ulf; Klostermeier, Dagmar

    2017-01-02

    Eukaryotic translation initiation starts with binding of the eIF4F complex to the 5'-m(7)G cap of the mRNA. Recruitment of the 43S pre-initiation complex (PIC), formed by the 40S ribosomal subunit and other translation initiation factors, leads to formation of the 48S PIC that then scans the 5'-untranslated region (5'-UTR) toward the start codon. The eIF4F complex consists of eIF4E, the cap binding protein, eIF4A, a DEAD-box RNA helicase that is believed to unwind secondary structures in the 5'-UTR during scanning, and eIF4G, a scaffold protein that binds to both eIF4E and eIF4A. The ATPase and helicase activities of eIF4A are jointly stimulated by eIF4G and the translation initiation factor eIF4B. Yeast eIF4B mediates recruitment of the 43S PIC to the cap-bound eIF4F complex by interacting with the 40S subunit and possibly with eIF4A. However, a direct interaction between yeast eIF4A and eIF4B has not been demonstrated yet. Here we show that eIF4B binds to eIF4A in the presence of RNA and ADPNP, independent of the presence of eIF4G. A stretch of seven moderately conserved repeats, the r1-7 region, is responsible for complex formation, for modulation of the conformational energy landscape of eIF4A by eIF4B, and for stimulating the RNA-dependent ATPase- and ATP-dependent RNA unwinding activities of eIF4A. The isolated r1-7 region only slightly stimulates eIF4A conformational changes and activities, suggesting that communication of the repeats with other regions of eIF4B is required for full stimulation of eIF4A activity, for recruitment of the PIC to the mRNA and for translation initiation.

  16. The Function of HMG-Box Transcription Factors Sox4a and Sox4b in Zebrafish Bone Development and Homeostasis

    NASA Astrophysics Data System (ADS)

    Aceto, J.; Motte, P.; Martial, J. A.; Muller, M.

    2008-06-01

    In mammals, the Sox4 gene is involved in development of endocardial crests, the brain, the lung, teeth, gonads and lymphocytes. Recently, Sox4 was shown to control bone mass and mineralization in mice. In zebrafish, two homologs for the mammalian Sox4 are present, sox4a and sox4b. Here we investigate the function of the sox4a and sox4b genes in cartilage and bone development in zebrafish. Therefore, we focus our attention on the first bone structures to be formed, the head skeleton and more precisely the pharyngeal cartilage. We show that both genes are expressed in the pharyngeal region, albeit at different time points during development. Double in situ hybridization experiments are used to exactly define the particular tissues where they are expressed. Furthermore, microinjection experiments of antisense oligonucleotides are used to block translation of these specific genes and to define their precise function during cartilage and bone development.

  17. The plasma membrane Ca2+ pump isoform 4a differs from isoform 4b in the mechanism of calmodulin binding and activation kinetics: implications for Ca2+ signaling.

    PubMed

    Caride, Ariel J; Filoteo, Adelaida G; Penniston, John T; Strehler, Emanuel E

    2007-08-31

    The inhibition by the regulatory domain and the interaction with calmodulin (CaM) vary among plasma membrane calcium pump (PMCA) isoforms. To explore these differences, the kinetics of CaM effects on PMCA4a were investigated and compared with those of PMCA4b. The maximal apparent rate constant for CaM activation of PMCA4a was almost twice that for PMCA4b, whereas the rates of activation for both isoforms showed similar dependence on Ca2+. The inactivation of PMCA4a by CaM removal was also faster than for PMCA4b, and Ca2+ showed a much smaller effect (2- versus 30-fold modification). The rate constants of the individual steps that determine the overall rates were obtained from stopped-flow experiments in which binding of TA-CaM was observed by changes in its fluorescence. TA-CaM binds to two conformations of PMCA4a, an "open" conformation with high activity, and a "closed" one with lower activity. Compared with PMCA4b (Penheiter, A. R., Bajzer, Z., Filoteo, A. G., Thorogate, R., Török, K., and Caride, A. J. (2003) Biochemistry 41, 12115-12124), the model for PMCA4a predicts less inhibition in the closed form and a much faster equilibrium between the open and closed forms. Based on the available kinetic parameters, we determined the constants to fit the shape of a Ca2+ signal in PMCA4b-overexpressing Chinese hamster ovary cells. Using the constants for PMCA4a, and allowing small variations in parameters of other systems contributing to a Ca2+ signal, we then simulated the effect of PMCA4a on the shape of a Ca2+ signal in Chinese hamster ovary cells. The results reproduce the published data (Brini, M., Coletto, L., Pierobon, N., Kraev, N., Guerini, D., and Carafoli, E. (2003) J. Biol. Chem. 278, 24500-24508), and thereby demonstrate the importance of altered regulatory kinetics for the different functional properties of PMCA isoforms.

  18. Methylation of CpG island of p14(ARK), p15(INK4b) and p16(INK4a) genes in coke oven workers.

    PubMed

    Zhang, H; Li, X; Ge, L; Yang, J; Sun, J; Niu, Q

    2015-02-01

    To detect the blood genomic DNA methylation in coke oven workers and find a possible early screening index for occupational lung cancer, 74 coke oven workers as the exposed group and 47 water pump workers as the controls were surveyed, and urine samples and peripheral blood mononuclear cells (PBMCs) were collected. Airborne benzo[a]pyrene (B[a]P) levels in workplace and urinary 1-hydroxypyrene (1-OH-Py) levels were determined by high-performance liquid chromatography. DNA damage of PBMCs and the p14(ARK), p15(INK4b) and p16(INK4a) gene CpG island methylation in the promoter region were detected by comet assay and methylation-specific polymerase chain reaction techniques, respectively. Results show that compared with the controls, concentration of airborne B[a]Ps was elevated in the coke plant, and urinary 1-OH-Py's level and DNA olive tail moment in comet assay were significantly increased in the coke oven workers, and p14(ARK), p15(INK4b) and p16(INK4a) gene methylation rates were also significantly increased. With the working years and urinary 1-OH-Py's level, the rates of p14(ARK) and p16(INK4a) gene methylation were significantly increased while that of p15(INK4b) gene methylation displayed no statistical change. We conclude that PBMCs' p14(ARK) and p16(INK4a) gene methylation may be used for screening and warning lung cancer in coke oven workers.

  19. Substitution of a single amino acid (aspartic acid for histidine) converts the functional activity of human complement C4B to C4A.

    PubMed Central

    Carroll, M C; Fathallah, D M; Bergamaschini, L; Alicot, E M; Isenman, D E

    1990-01-01

    The C4B isotype of the fourth component of human complement (C4) displays 3- to 4-fold greater hemolytic activity than does its other isotype C4A. This correlates with differences in their covalent binding efficiencies to erythrocytes coated with antibody and complement C1. C4A binds to a greater extent when C1 is on IgG immune aggregates. The differences in covalent binding properties correlate only with amino acid changes between residues 1101 and 1106 (pro-C4 numbering)--namely, Pro-1101, Cys-1102, Leu-1105, and Asp-1106 in C4A and Leu-1101, Ser-1102, Ile-1105, and His-1106 in C4B, which are located in the C4d region of the alpha chain. To more precisely identify the residues that are important for the functional differences, C4A-C4B hybrid proteins were constructed by using recombinant DNA techniques. Comparison of these by hemolytic assay and binding to IgG aggregates showed that the single substitution of aspartic acid for histidine at position 1106 largely accounted for the change in functional activity and nature of the chemical bond formed (ester vs. amide). Surprisingly, substitution of a neutral residue, alanine, for histidine at position 1106 resulted in an increase in binding to immune aggregates without subsequent reduction in the hemolytic activity. This result strongly suggests that position 1106 is not "catalytic" as previously proposed but interacts sterically/electrostatically with potential acceptor sites and serves to "select" binding sites on potential acceptor molecules. Images PMID:2395880

  20. NOGO-A/RTN4A and NOGO-B/RTN4B are simultaneously expressed in epithelial, fibroblast and neuronal cells and maintain ER morphology

    PubMed Central

    Rämö, Olli; Kumar, Darshan; Gucciardo, Erika; Joensuu, Merja; Saarekas, Maiju; Vihinen, Helena; Belevich, Ilya; Smolander, Olli-Pekka; Qian, Kui; Auvinen, Petri; Jokitalo, Eija

    2016-01-01

    Reticulons (RTNs) are a large family of membrane associated proteins with various functions. NOGO-A/RTN4A has a well-known function in limiting neurite outgrowth and restricting the plasticity of the mammalian central nervous system. On the other hand, Reticulon 4 proteins were shown to be involved in forming and maintaining endoplasmic reticulum (ER) tubules. Using comparative transcriptome analysis and qPCR, we show here that NOGO-B/RTN4B and NOGO-A/RTN4A are simultaneously expressed in cultured epithelial, fibroblast and neuronal cells. Electron tomography combined with immunolabelling reveal that both isoforms localize preferably to curved membranes on ER tubules and sheet edges. Morphological analysis of cells with manipulated levels of NOGO-B/RTN4B revealed that it is required for maintenance of normal ER shape; over-expression changes the sheet/tubule balance strongly towards tubules and causes the deformation of the cell shape while depletion of the protein induces formation of large peripheral ER sheets. PMID:27786289

  1. NOGO-A/RTN4A and NOGO-B/RTN4B are simultaneously expressed in epithelial, fibroblast and neuronal cells and maintain ER morphology.

    PubMed

    Rämö, Olli; Kumar, Darshan; Gucciardo, Erika; Joensuu, Merja; Saarekas, Maiju; Vihinen, Helena; Belevich, Ilya; Smolander, Olli-Pekka; Qian, Kui; Auvinen, Petri; Jokitalo, Eija

    2016-10-27

    Reticulons (RTNs) are a large family of membrane associated proteins with various functions. NOGO-A/RTN4A has a well-known function in limiting neurite outgrowth and restricting the plasticity of the mammalian central nervous system. On the other hand, Reticulon 4 proteins were shown to be involved in forming and maintaining endoplasmic reticulum (ER) tubules. Using comparative transcriptome analysis and qPCR, we show here that NOGO-B/RTN4B and NOGO-A/RTN4A are simultaneously expressed in cultured epithelial, fibroblast and neuronal cells. Electron tomography combined with immunolabelling reveal that both isoforms localize preferably to curved membranes on ER tubules and sheet edges. Morphological analysis of cells with manipulated levels of NOGO-B/RTN4B revealed that it is required for maintenance of normal ER shape; over-expression changes the sheet/tubule balance strongly towards tubules and causes the deformation of the cell shape while depletion of the protein induces formation of large peripheral ER sheets.

  2. Purification and characterization of two novel antimicrobial peptides Subpeptin JM4-A and Subpeptin JM4-B produced by Bacillus subtilis JM4.

    PubMed

    Wu, Shimei; Jia, Shifang; Sun, Dandan; Chen, Meiling; Chen, Xiuzhu; Zhong, Jin; Huan, Liandong

    2005-11-01

    An antimicrobial peptides-producing strain was isolated from soil and identified as Bacillus subtilis JM4 according to biochemical tests and 16S rDNA sequence analysis. The corresponding antimicrobial peptides were purified to homogeneity by ammonium sulfate precipitation, sequential SP-Sepharose Fast Flow, Sephadex G-25 and C18 reverse-phase chromatography, and in the final purification step, two active fractions were harvested, designated as Subpeptin JM4-A and Subpeptin JM4-B. The molecular weights, determined by mass spectrometry, were 1422.71 Da for Subpeptin JM4-A and 1422.65 Da for Subpeptin JM4-B, respectively. Amino acid sequencing showed that they differed from each other only at the seventh amino acid except for three unidentified residues, and the two peptides had no significant sequence homology to the known peptides in the database, indicating that they are two novel antimicrobial peptides. In addition, characteristic measurements indicated that both peptides had a relatively broad inhibitory spectrum and remained active over a wide pH and temperature range.

  3. Mutational analysis of genes p14ARF, p15INK4b, p16INK4a, and PTEN in human nervous system tumors.

    PubMed

    Almeida, L O; Custódio, A C; Araújo, J J; Rey, J A; Almeida, J R W; Santos, M J; Clara, C A; Casartelli, C

    2008-05-27

    Cancer is one of the most common and severe problems in clinical medicine, and nervous system tumors represent about 2% of the types of cancer. The central role of the nervous system in the maintenance of vital activities and the functional consequences of the loss of neurons can explain how severe brain cancers are. The cell cycle is a highly complex process, with a wide number of regulatory proteins involved, and such proteins can suffer alterations that transform normal cells into malignant ones. The INK4 family members (CDK inhibitors) are the cell cycle regulators that block the progression of the cycle through the R point, causing an arrest in G1 stage. The p14ARF (alternative reading frame) gene is a tumor suppressor that inhibits p53 degradation during the progression of the cell cycle. The PTEN gene is related to the induction of growth suppression through cell cycle arrest, to apoptosis and to the inhibition of cell adhesion and migration. The purpose of the present study was to assess the mutational state of the genes p14ARF, p15INK4b, p16INK4a, and PTEN in 64 human nervous system tumor samples. Homozygous deletions were found in exon 2 of the p15INK4b gene and exon 3 of the p16INK4a gene in two schwannomas. Three samples showed a guanine deletion (63 codon) which led to a loss of heterozygosity in the p15 gene, and no alterations could be seen in the PTEN gene. Although the group of patients was heterogeneous, our results are in accordance with other different studies that indicate that homozygous deletion and loss of heterozygosity in the INK4 family members are frequently observed in nervous system tumors.

  4. AtCCR4a and AtCCR4b are Involved in Determining the Poly(A) Length of Granule-bound starch synthase 1 Transcript and Modulating Sucrose and Starch Metabolism in Arabidopsis thaliana.

    PubMed

    Suzuki, Yuya; Arae, Toshihiro; Green, Pamela J; Yamaguchi, Junji; Chiba, Yukako

    2015-05-01

    Removing the poly(A) tail is the first and rate-limiting step of mRNA degradation and apparently an effective step not only for modulating mRNA stability but also for translation of many eukaryotic transcripts. Carbon catabolite repressor 4 (CCR4) has been identified as a major cytoplasmic deadenylase in Saccharomyces cerevisiae. The Arabidopsis thaliana homologs of the yeast CCR4, AtCCR4a and AtCCR4b, were identified by sequence-based analysis; however, their role and physiological significance in plants remain to be elucidated. In this study, we revealed that AtCCR4a and AtCCR4b are localized to cytoplasmic mRNA processing bodies, which are specific granules consisting of many enzymes involved in mRNA turnover. Double mutants of AtCCR4a and AtCCR4b exhibited tolerance to sucrose application but not to glucose. The levels of sucrose in the seedlings of the atccr4a/4b double mutants were reduced, whereas no difference was observed in glucose levels. Further, amylose levels were slightly but significantly increased in the atccr4a/4b double mutants. Consistent with this observation, we found that the transcript encoding granule-bound starch synthase 1 (GBSS1), which is responsible for amylose synthesis, is accumulated to a higher level in the atccr4a/4b double mutant plants than in the control plants. Moreover, we revealed that GBSS1 has a longer poly(A) tail in the double mutant than in the control plant, suggesting that AtCCR4a and AtCCR4b can influence the poly(A) length of transcripts related to starch metabolism. Our results collectively suggested that AtCCR4a and AtCCR4b are involved in sucrose and starch metabolism in A. thaliana.

  5. A single-amino acid substitution in West Nile virus 2K peptide between NS4A and NS4B confers resistance to lycorine, a flavivirus inhibitor

    PubMed Central

    Zou, Gang; Puig-Basagoiti, Francesc; Zhang, Bo; Qing, Min; Chen, Liqiang; Pankiewicz, Krzysztof W.; Felczak, Krzysztof; Yuan, Zhiming; Shi, Pei-Yong

    2017-01-01

    Lycorine potently inhibits flaviviruses in cell culture. At 1.2-μM concentration, lycorine reduced viral titers of West Nile (WNV), dengue, and yellow fever viruses by 102- to 104-fold. However, the compound did not inhibit an alphavirus (Western equine encephalitis virus) or a rhabdovirus (vesicular stomatitis virus), indicating a selective antiviral spectrum. The compound exerts its antiviral activity mainly through suppression of viral RNA replication. A Val→Met substitution at the 9th amino acid position of the viral 2K peptide (spanning the endoplasmic reticulum membrane between NS4A and NS4B proteins) confers WNV resistance to lycorine, through enhancement of viral RNA replication. Initial chemistry synthesis demonstrated that modifications of the two hydroxyl groups of lycorine can increase the compound’s potency, while reducing its cytotoxicity. Taken together, the results have established lycorine as a flavivirus inhibitor for antiviral development. The lycorine-resistance results demonstrate a direct role of the 2K peptide in flavivirus RNA synthesis. PMID:19062063

  6. Accidental Conical Intersections in Mixed Trimers of Potassium and Rubidium: a Vibronic Analysis of the 4^4B_2 and 3^4A_1 States

    NASA Astrophysics Data System (ADS)

    Hauser, A. W.; Auböck, G.; Callegari, C.; Ernst, W. E.

    2010-06-01

    We compare the 3^4A_1 and 4^4B_2 states of homonuclear and heteronuclear alkali trimers formed of potassium and rubidium. The Multireference Rayleigh Schrödinger Perturbation Theory of second order is applied to obtain the corresponding adiabatic potential energy surfaces. In the case of homonuclear trimers these pairs of states correspond to the two branches of the E×{}e Jahn-Teller distorted 2^4E^' state. For heteronuclear trimers, the vibrational modes Q_x and Q_y are no longer degenerate, but the two electronic states still show a conical intersection at obtuse (KRb_2) or acute (K_2Rb) isosceles geometries. Spectroscopic consequences of this situation are discussed, vibronic spectra are predicted and compared to LIF spectra obtained in helium droplet isolation spectroscopy experiments of our group. J. Nagl, G. Auböck, A.W. Hauser, O. Allard, C. Callegari and W.E. Ernst, Phys. Rev. Lett. 100, 063001 (2008) J. Nagl, G. Auböck, A.W. Hauser, O. Allard, C. Callegari and W.E. Ernst, J. Chem. Phys. 128, 154320 (2008)

  7. APEX-CHAMP+ high-J CO observations of low-mass young stellar objects. III. NGC 1333 IRAS 4A/4B envelope, outflow, and ultraviolet heating

    NASA Astrophysics Data System (ADS)

    Yıldız, Umut A.; Kristensen, Lars E.; van Dishoeck, Ewine F.; Belloche, Arnaud; van Kempen, Tim A.; Hogerheijde, Michiel R.; Güsten, Rolf; van der Marel, Nienke

    2012-06-01

    Context. The NGC 1333 IRAS 4A and IRAS 4B sources are among the most well-studied Stage 0 low-mass protostars, which drive prominent bipolar outflows. Spectrally resolved molecular emission lines provide crucial information about the physical and chemical structure of the circumstellar material as well as the dynamics of the different components. Most studies have so far concentrated on the colder parts (T ≤ 30 K) of these regions. Aims: The aim is to characterize the warmer parts of the protostellar envelope using the new generation of submillimeter instruments. This will allow us to quantify the feedback of the protostars on their surroundings in terms of shocks, ultraviolet (UV) heating, photodissociation, and outflow dispersal. Methods: The dual frequency 2 × 7 pixel 650/850 GHz array receiver CHAMP+ mounted on APEX was used to obtain a fully sampled, large-scale ~4' × 4' map at 9″ resolution of the IRAS 4A/4B region in the 12CO J = 6-5 line. Smaller maps were observed in the 13CO 6-5 and [C i] J = 2-1 lines. In addition, a fully sampled 12CO J = 3-2 map made with HARP-B on the JCMT is presented and deep isotopolog observations are obtained at selected outflow positions to constrain the optical depth. Complementary Herschel-HIFI and ground-based lines of CO and its isotopologs, from J = 1-0 up to 10-9 (Eu/k ≈ 300 K), are collected at the source positions and used to construct velocity-resolved CO ladders and rotational diagrams. Radiative-transfer models of the dust and lines are used to determine the temperatures and masses of the outflowing and photon-heated gas and infer the CO abundance structure. Results: Broad CO emission-line profiles trace entrained shocked gas along the outflow walls, which have an average temperature of ~100 K. At other positions surrounding the outflow and the protostar, the 6-5 line profiles are narrow indicating UV excitation. The narrow 13CO 6-5 data directly reveal the UV heated gas distribution for the first time. The

  8. International Conference on Harmonisation; guidance on Q4B Evaluation and Recommendation of Pharmacopoeial Texts for use in the International Conference on Harmonisation Regions; Annex 4C on Microbiological Examination of Nonsterile Products: Acceptance Criteria for Pharmaceutical Preparations and Substances for Pharmaceutical Use General Chapter; availability. Notice.

    PubMed

    2009-04-08

    The Food and Drug Administration (FDA) is announcing the availability of a guidance entitled "Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the ICH Regions; Annex 4C: Microbiological Examination of Nonsterile Products: Acceptance Criteria for Pharmaceutical Preparations and Substances for Pharmaceutical Use General Chapter." The guidance was prepared under the auspices of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH). The guidance provides the results of the ICH Q4B evaluation of the Microbiological Examination of Nonsterile Products: Acceptance Criteria for Pharmaceutical Preparations and Substances for Pharmaceutical Use General Chapter harmonized text from each of the three pharmacopoeias (United States, European, and Japanese) represented by the Pharmacopoeial Discussion Group (PDG). The guidance conveys recognition of the three pharmacopoeial methods by the three ICH regulatory regions and provides specific information regarding the recognition. The guidance is intended to recognize the interchangeability between the local regional pharmacopoeias, thus avoiding redundant testing in favor of a common testing strategy in each regulatory region. In the Federal Register of February 21, 2008 (73 FR 9575), FDA made available a guidance on the Q4B process entitled "Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the ICH Regions."

  9. Gene Copy-Number Variations (CNVs) and Protein Levels of Complement C4A and C4B as Novel Biomarkers for Partial Disease Remissions in New-Onset Type 1 Diabetes Patients

    PubMed Central

    Kingery, Suzanne E.; Wu, Yee Ling; Zhou, Bi; Hoffman, Robert P.; Yu, C. Yung

    2014-01-01

    Objective To determine the roles of complement C4A and C4B gene CNVs and their plasma protein concentrations in residual insulin secretion and loss of pancreatic beta-cell function in new-onset type 1 diabetes patients. Methods We studied 34 patients of European ancestry with new-onset type 1 diabetes, aged between 3 and 17 years (10.7±3.45), at Nationwide Children's Hospital in Columbus, Ohio. Gene copy-number and size variations of complement C4A and C4B were determined by genomic Southern blot analyses. C4A and C4B protein phenotypes were elucidated by immunofixation and radial immunodiffusion. Two-digit HLA-DRB1 genotypes were determined by sequence-specific PCR. At 1 month and 9-month post diagnosis, stimulated C-peptide levels were measured after a standardized mixed-meal tolerance test. Results The diploid gene copy-numbers of C4A varied from 0 to 4, and those of C4B from 0 to 3. Patients with higher copy-number of C4A or higher C4A plasma protein concentrations at diagnosis had higher C-peptide levels at 1 month post diagnosis (p=0.008; p=0.008). When controlled by the Z-score of body-mass index, C4A copy-numbers, C4A protein concentrations, the age of disease-onset, the number of HLA-DR3 but not DR4 alleles were significant parameters in determining C-peptide levels. At 9-month post diagnosis, 42.3% of patients remained in partial remission, and these patients were characterized by lower total C4B copy-numbers or lower C4B protein concentrations (p=0.02, p=0.0004). Conclusions C4A appears to associate with the protection of residual beta-cell function in new-onset type 1 diabetes; C4B is correlated with the end of disease remission at 9-month post diagnosis. PMID:22151770

  10. Duplex unwinding and ATPase activities of the DEAD-box helicase eIF4A are coupled by eIF4G and eIF4B.

    PubMed

    Özeş, Ali R; Feoktistova, Kateryna; Avanzino, Brian C; Fraser, Christopher S

    2011-09-30

    Eukaryotic initiation factor (eIF) 4A is a DEAD-box helicase that stimulates translation initiation by unwinding mRNA secondary structure. The accessory proteins eIF4G, eIF4B, and eIF4H enhance the duplex unwinding activity of eIF4A, but the extent to which they modulate eIF4A activity is poorly understood. Here, we use real-time fluorescence assays to determine the kinetic parameters of duplex unwinding and ATP hydrolysis by these initiation factors. To ensure efficient duplex unwinding, eIF4B and eIF4G cooperatively activate the duplex unwinding activity of eIF4A. Our data reveal that eIF4H is much less efficient at stimulating eIF4A unwinding activity than eIF4B, implying that eIF4H is not able to completely substitute for eIF4B in duplex unwinding. By monitoring unwinding and ATPase assays under identical conditions, we demonstrate that eIF4B couples the ATP hydrolysis cycle of eIF4A with strand separation, thereby minimizing nonproductive unwinding events. Using duplex substrates with altered GC contents but similar predicted thermal stabilities, we further show that the rate of formation of productive unwinding complexes is strongly influenced by the local stability per base pair, in addition to the stability of the entire duplex. This finding explains how a change in the GC content of a hairpin is able to influence translation initiation while maintaining the overall predicted thermal stability.

  11. Luminescent Immunoprecipitation System (LIPS) for Detection of Autoantibodies Against ATP4A and ATP4B Subunits of Gastric Proton Pump H+,K+-ATPase in Atrophic Body Gastritis Patients

    PubMed Central

    Lahner, Edith; Brigatti, Cristina; Marzinotto, Ilaria; Carabotti, Marilia; Scalese, Giulia; Davidson, Howard W; Wenzlau, Janet M; Bosi, Emanuele; Piemonti, Lorenzo; Annibale, Bruno; Lampasona, Vito

    2017-01-01

    Objectives: Circulating autoantibodies targeting the H+/K+-ATPase proton pump of gastric parietal cells are considered markers of autoimmune gastritis, whose diagnostic accuracy in atrophic body gastritis, the pathological lesion of autoimmune gastritis, remains unknown. This study aimed to assess autoantibodies against ATP4A and ATP4B subunits of parietal cells H+, K+-ATPase in atrophic body gastritis patients and controls. Methods: One-hundred and four cases with atrophic body gastritis and 205 controls were assessed for serological autoantibodies specific for ATP4A or ATP4B subunits using luminescent immunoprecipitation system (LIPS). Recombinant luciferase-reporter-fused-antigens were expressed by in vitro transcription-translation (ATP4A) or after transfection in Expi293F cells (ATP4B), incubated with test sera, and immune complexes recovered using protein-A-sepharose. LIPS assays were compared with a commercial enzyme immunoassay (EIA) for parietal cell autoantibodies. Results: ATP4A and ATP4B autoantibody titers were higher in cases compared to controls (P<0.0001). The area under the receiver-operating characteristic curve was 0.98 (95% CI 0.965–0.996) for ATP4A, and 0.99 (95% CI 0.979–1.000) for ATP4B, both higher as compared with that of EIA: 0.86 (95% CI 0.809–0.896), P<0.0001. Sensitivity-specificity were 100–89% for ATP4A and 100–90% for ATP4B assay. Compared with LIPS, EIA for parietal cell autoantibodies showed a lower sensitivity (72%, P<0.0001) at a similar specificity (92%, P=0.558). Conclusions: Positivity to both, ATP4A and ATP4B autoantibodies is closely associated with atrophic body gastritis. Both assays had the highest sensitivity, at the cost of diagnostic accuracy (89 and 90% specificity), outperforming traditional EIA. Once validated, these LIPS assays should be valuable screening tools for detecting biomarkers of damaged atrophic oxyntic mucosa. PMID:28102858

  12. An allele-specific PCR system for rapid detection and discrimination of the CYP2C19∗4A, ∗4B, and ∗17 alleles: implications for clopidogrel response testing.

    PubMed

    Scott, Stuart A; Tan, Qian; Baber, Usman; Yang, Yao; Martis, Suparna; Bander, Jeffrey; Kornreich, Ruth; Hulot, Jean-Sébastien; Desnick, Robert J

    2013-11-01

    CYP2C19 is involved in the metabolism of clinically relevant drugs, including the antiplatelet prodrug clopidogrel, which has prompted interest in clinical CYP2C19 genotyping. The CYP2C19∗4B allele is defined by both gain-of-function [c.-806C>T (∗17)] and loss-of-function [c.1A>G (∗4)] variants on the same haplotype; however, current genotyping and sequencing assays are unable to determine the phase of these variants. Thus, the aim of this study was to develop an assay that could rapidly detect and discriminate the related ∗4A, ∗4B, and ∗17 alleles. An allele-specific PCR assay, composed of four unique primer mixes that specifically interrogate the defining ∗17 and ∗4 variants, was developed by using samples (n = 20) with known genotypes, including the ∗4A, ∗4B, and/or ∗17 alleles. The assay was validated by testing 135 blinded samples, and the results were correlated with CYP2C19 genotyping and allele-specific cloning/sequencing. Importantly, among the six ∗4 carriers in the validation cohort, after allele-specific PCR testing both samples with a ∗1/∗4 genotype were reclassified to ∗1/∗4A, all three samples with a ∗4/∗17 genotype were reclassified to ∗1/∗4B, and a sample with a ∗4/∗17/∗17 genotype was reclassified to ∗4B/∗17. In conclusion, this rapid and robust allele-specific PCR assay can refine CYP2C19 genotyping and metabolizer phenotype classification by determining the phase of the defining ∗17 and ∗4 variants, which may have utility when testing CYP2C19 for clopidogrel response.

  13. International Conference on Harmonisation; guidance on Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on Harmonisation Regions; Annex 4A on Microbiological Examination of Nonsterile Products: Microbial Enumeration Tests General Chapter; availability. Notice.

    PubMed

    2009-04-08

    The Food and Drug Administration (FDA) is announcing the availability of a guidance entitled "Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the ICH Regions; Annex 4A: Microbiological Examination of Nonsterile Products: Microbial Enumeration Tests General Chapter." The guidance was prepared under the auspices of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH). The guidance provides the results of the ICH Q4B evaluation of the Microbiological Examination of Nonsterile Products: Microbial Enumeration Tests General Chapter harmonized text from each of the three pharmacopoeias (United States, European, and Japanese) represented by the Pharmacopoeial Discussion Group (PDG). The guidance conveys recognition of the three pharmacopoeial methods by the three ICH regulatory regions and provides specific information regarding the recognition. The guidance is intended to recognize the interchangeability between the local regional pharmacopoeias, thus avoiding redundant testing in favor of a common testing strategy in each regulatory region. In the Federal Register of February 21, 2008 (73 FR 9575), FDA made available a guidance on the Q4B process entitled "Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the ICH Regions."

  14. Anxiogenic-Like Behavioral Phenotype of Mice Deficient in Phosphodiesterase 4B (PDE4B)

    PubMed Central

    Zhang, Han-Ting; Huang, Ying; Masood, Anbrin; Stolinski, Lisa R; Li, Yunfeng; Zhang, Lei; Dlaboga, Daniel; Jin, S-L Catherine; Conti, Marco; O’Donnell, James M

    2009-01-01

    Phosphodiesterase-4 (PDE4), an enzyme that catalyzes the hydrolysis of cyclic AMP and plays a critical role in controlling its intracellular concentration, has been implicated in depression- and anxiety-like behaviors. However, the functions of the four PDE4 subfamilies (PDE4A, PDE4B, PDE4C, and PDE4D) remain largely unknown. In animal tests sensitive to anxiolytics, antidepressants, memory enhancers, or analgesics, we examined the behavioral phenotype of mice deficient in PDE4B (PDE4B−/−). Immunoblot analysis revealed loss of PDE4B expression in the cerebral cortex and amygdala of PDE4B−/− mice. The reduction of PDE4B expression was accompanied by decreases in PDE4 activity in the brain regions of PDE4B−/− mice. Compared to PDE4B + / + littermates, PDE4B−/− mice displayed anxiogenic-like behavior, as evidenced by decreased head-dips and time spent in head-dipping in the holeboard test, reduced transitions and time on the light side in the light–dark transition test, and decreased initial exploration and rears in the open-field test. Consistent with anxiogenic-like behavior, PDE4B−/− mice displayed increased levels of plasma corticosterone. In addition, these mice also showed a modest increase in the proliferation of neuronal cells in the hippocampal dentate gyrus. In the forced-swim test, PDE4B−/− mice exhibited decreased immobility; however, this was not supported by the results from the tail-suspension test. PDE4B−/− mice did not display changes in memory, locomotor activity, or nociceptive responses. Taken together, these results suggest that the PDE4B subfamily is involved in signaling pathways that contribute to anxiogenic-like effects on behavior PMID:17700644

  15. Endothelial nitric oxide synthase (eNOS) T-786C, 4a4b, and G894T polymorphisms and male infertility: study for idiopathic asthenozoospermia and meta-analysis.

    PubMed

    Song, Pingping; Zou, Shasha; Chen, Tingting; Chen, Jianhua; Wang, Yanan; Yang, Juanjuan; Song, Zhijian; Jiang, Huayu; Shi, Huijuan; Huang, Yiran; Li, Zheng; Shi, Yongyong; Hu, Hongliang

    2015-02-01

    Recent studies on the eNOS gene and male infertility show that expression of eNOS regulates normal spermatogenesis in the testis, and the eNOS gene variants (T-786C, 4a4b, and G894T) are potentially involved in impairment of spermatogenesis and sperm function. Thus, we conducted this association and meta-analysis study to further validate whether variants of those three loci affected the risk of idiopathic asthenozoospermia (AZS) and male infertility. Approximately 340 Chinese idiopathic AZS patients and 342 healthy men were included for this case-control study, genotyped by gel electrophoresis analysis or direct sequencing of PCR products. The eNOS mRNA isolated from the semen of patients was further examined by quantitative real-time PCR. Also, a meta-analysis of association between eNOS gene polymorphisms and male infertility was performed. A significant association was identified on allelic level between 4a4b variant and AZS in our study (chi-squared = 7.53, corrected P = 0.018, odds ratio (OR) = 1.808), while there were no significant difference of T-786C and G894T for asthenozoospermia in both genotype and allele distributions. In addition, expression of eNOS was up-regulated in patients compared with controls (about 2.4-fold, P < 0.001). Furthermore, the results of the meta-analysis support the conclusion that the T-786C and 4a4b loci were associated with male infertility in both Asian and Caucasian populations. Our study provides genetic evidence for the eNOS gene being a risk factor for idiopathic AZS and male infertility. Considering genetic differences among populations and complex pathogenesis of male infertility, more validating studies using independent samples are suggested in the future.

  16. Species-specific but not genotype-specific primary and secondary isotype-specific NSP4 antibody responses in gnotobiotic calves and piglets infected with homologous host bovine (NSP4[A]) or porcine (NSP4[B]) rotavirus.

    PubMed

    Yuan, Lijuan; Honma, Shinjiro; Ishida, Shin-Ichi; Yan, Xiao-Yi; Kapikian, Albert Z; Hoshino, Yasutaka

    2004-12-05

    Using recombinant baculoviruses expressing rotavirus NSP4 [A], [B], [C], and [D] genotypes of bovine, porcine, human, simian, or murine origin, we analyzed serum antibody responses to NSP4s in gnotobiotic calves and piglets infected by the oral/alimentary or intraamniotic route with bovine (NSP4[A]) (Wyatt, R.G., Mebus, C.A., Yolken, R.H., Kalica, A.R., James, H.D., Jr., Kapikian, A.Z., Chanock, R.M., 1979. Rotaviral immunity in gnotobiotic calves: heterologous resistance to human virus induced by bovine virus. Science 203(4380), 548-550) or porcine (NSP4[B]) (Hoshino, Y., Saif, L.J., Sereno, M.M., Chanock, R.M., Kapikian, A.Z., 1988. Infection immunity of piglets to either VP3 or VP7 outer capsid protein confers resistance to challenge with a virulent rotavirus bearing the corresponding antigen. J. Virol. 62(3), 744-748) rotaviruses. Following primary infection and challenge with virulent rotaviruses, the animals developed higher or significantly higher antibody titers to homologous host homotypic NSP4s than to heterologous host homotypic or heterologous host heterotypic NSP4s, indicating that antibody responses were species specific rather than genotype specific. Antibody responses to NSP4s corresponded closely with the phylogenetic relationships of NSP4s within a species-specific region of amino acids (aa) 131-141. In contrast, NSP4 genotypes determined by amino acid full-length sequence identity predicted poorly their "serotypes". In piglets, antibodies to NSP4 induced by previous oral infection failed to confer protection against challenge from a porcine rotavirus bearing serotypically different VP4 and VP7 but essentially identical NSP4 to the porcine rotavirus in primary infection. Thus, in an approach to immunization with a live oral rotavirus vaccine, the NSP4 protein does not appear to play an important role in protection against rotavirus disease and infection.

  17. Deregulated E2F-1 blocks terminal differentiation and loss of leukemogenicity of M1 myeloblastic leukemia cells without abrogating induction of p15(INK4B) and p16(INK4A).

    PubMed

    Amanullah, A; Hoffman, B; Liebermann, D A

    2000-07-15

    The transcription factor E2F-1 has been postulated to play a crucial role in the control of cell cycle progression because of its ability to be bound and regulated by the retinoblastoma gene product (pRb). Exogenous expression of E2F-1, under growth restrictive conditions, was shown to result in p53-dependent programmed cell death. The consequences of deregulated expression of E2F-1 on terminal differentiation of hematopoietic cells in the absence of E2F-1-mediated apoptosis, as well as mechanistic insights into how deregulated E2F-1 may affect terminal differentiation, have not been established. The autonomously proliferating M1 myeloblastic leukemia cell line, which is null for p53 expression and can be induced by interleukin-6 (IL-6) to undergo terminal macrophage differentiation with concomitant loss of leukemogenicity, provides a particularly attractive model system to address these issues. Deregulated and continued expression of E2F-1 blocked the IL-6-induced terminal differentiation program at an early blast stage, giving rise to immature cells, which continued to proliferate without undergoing apoptosis and retained their leukemogenic phenotype. Although E2F-1 blocked IL-6-mediated terminal differentiation and its associated growth arrest, it did not prevent the rapid induction of both p15(INK4B) and p16(INK4A), inhibition of cdk4 kinase activity, and subsequent hypophosphorylation of pRb. The results obtained imply that genetic alterations that both impair p53 function and deregulate E2F-1 expression may render hematopoietic cells refractory to the induction of differentiation and are, thereby, likely to play a major role in the progression of leukemias. (Blood. 2000;96:475-482)

  18. Carcinogen-specific mutational and epigenetic alterations in INK4A, INK4B and p53 tumour-suppressor genes drive induced senescence bypass in normal diploid mammalian cells.

    PubMed

    Yasaei, H; Gilham, E; Pickles, J C; Roberts, T P; O'Donovan, M; Newbold, R F

    2013-01-10

    Immortalization (senescence bypass) is a critical rate-limiting step in the malignant transformation of mammalian somatic cells. Human cells must breach at least two distinct senescence barriers to permit unfettered clonal evolution during cancer development: (1) stress- or oncogene-induced premature senescence (SIPS/OIS), mediated via the p16-Rb and/or ARF-p53-p21 tumour-suppressive pathways, and (2) replicative senescence triggered by telomere shortening. In contrast, because their telomerase is constitutively active, cells from small rodents possess only the SIPS/OIS barrier, and are therefore useful for studying SIPS/OIS bypass in isolation. Dermal fibroblasts from the Syrian hamster (SHD cells) are exceptionally resistant to spontaneous SIPS bypass, but it can be readily induced following exposure to a wide range of chemical and physical carcinogens. Here we show that a spectrum of carcinogen-specific mutational and epigenetic alterations involving the INK4A (p16), p53 and INK4B (p15) genes are associated with induced SIPS bypass. With ionizing radiation, immortalization is invariably accompanied by efficient biallelic deletion of the complete INK4/CDKN2 locus. In comparison, SHD cells immortalized by the powerful polycyclic hydrocarbon carcinogen benzo(a)pyrene display transversion point mutations in the DNA-binding domain of p53 coupled with INK4 alterations such as loss of expression of p15. Epimutational silencing of p16 is the primary event associated with immortalization by nickel, a human non-genotoxic carcinogen. As SIPS/OIS bypass is a prerequisite for the immortalization of normal diploid human epithelial cells, our results with the SHD model will provide a basis for delineating combinations of key molecular changes underpinning this important event in human carcinogenesis.

  19. Strong HCV NS3/4a, NS4b, NS5a, NS5b-specific cellular immune responses induced in Rhesus macaques by a novel HCV genotype 1a/1b consensus DNA vaccine.

    PubMed

    Latimer, Brian; Toporovski, Roberta; Yan, Jian; Pankhong, Panyupa; Morrow, Matthew P; Khan, Amir S; Sardesai, Niranjan Y; Welles, Seth L; Jacobson, Jeffrey M; Weiner, David B; Kutzler, Michele A

    2014-01-01

    Chronic HCV is a surreptitious disease currently affecting approximately 3% of the world's population that can lead to liver failure and cancer decades following initial infection. However, there are currently no vaccines available for the prevention of chronic HCV. From patients who acutely resolve HCV infection, it is apparent that a strong and broad cytotoxic T lymphocyte (CTL) response is important in HCV clearance. DNA vaccines are naked plasmid DNA molecules that encode pathogen antigens to induce a pathogen-specific immune response. They are inexpensive to produce and have an excellent safety profile in animals and humans. Additionally, DNA vaccines are able to induce strong CTL responses, making them well-suited for an HCV vaccine. We aimed to maximize vaccine recipients' opportunity to induce a broad T cell response with a novel antigenic sequence, multi-antigen vaccine strategy. We have generated DNA plasmids encoding consensus sequences of HCV genotypes 1a and 1b non-structural proteins NS3/4a, NS4b, NS5a, and NS5b. Rhesus macaques were used to study the immunogenicity of these constructs. Four animals were immunized 3 times, 6 weeks apart, at a dose of 1.0mg per antigen construct, as an intramuscular injection followed by in vivo electroporation, which greatly increases DNA uptake by local cells. Immune responses were measured 2 weeks post-immunization regimen (PIR) in immunized rhesus macaques and showed a broad response to multiple HCV nonstructural antigens, with up to 4680 spot-forming units per million peripheral blood mononuclear cells (PBMCs) as measured by Interferon-γ ELISpot. In addition, multiparametric flow cytometry detected HCV-specific CD4+ and CD8+ T cell responses by intracellular cytokine staining and detected HCV-specific CD107a+/GrzB+ CD8+ T cells indicating an antigen specific cytolytic response 2 weeks PIR compared with baseline measurements. At the final study time point, 6 weeks PIR, HCV-specific CD45RA- memory-like T cells

  20. Amino acid residues 1101-1105 of the isotypic region of human C4B is important to the covalent binding activity of complement component C4.

    PubMed

    Reilly, B D; Levine, R P; Skanes, V M

    1991-11-01

    The C4A and C4B isotypes of human C4 show certain functional differences that stem from their relative preference for transacylation to amino (-NH2) vs hydroxyl (-OH) nucleophiles, respectively, on complement-activating surfaces. Comparison of amino acid sequences of the alpha-chain fragment of C4, C4d, has shown C4A- and C4B-specific sequences at residues 1101-1106 are the only consistent structural difference between isotype, i.e., Pro, Cys, Pro, Val, Leu, Asp in C4A and Leu, Ser, Pro, Val Ile, His in C4B. These residues may be responsible either in part or entirely for properties associated with isotype. To examine the functional role of residues 1101-1106 in C4B-mediated hemolysis, whole serum or immunopurified human C4 with allotypes, A3B1, A3, B2B1, or B1 were preincubated in the presence or absence of an antipeptide mAb (BII-1) specific for amino acid residues 1101-1105 of C4B. Sensitized sheep E and C4-deficient guinea pig serum was then added and lysis measured by absorbance at 415 nm. Our results show lysis of antibody-sensitized sheep E is inhibited by antibody and C4B2B1, C4B1, or C4A3B1 but not antibody and C4A3. The interference of hemolysis by BII-1 could not be explained by inhibition of activation of C4B or inhibition of C3 or C5 convertase activity. Furthermore, results from uptake experiments show that BII-1 interferes with the covalent binding activity of C4B, indicating residues 1101-1105 play a role in the covalent binding reaction of C4B to the target E-antibody complex.

  1. Boeing F4B-4

    NASA Technical Reports Server (NTRS)

    1932-01-01

    The Boeing F4B-4 was seen to differ from earlier F4Bs in having a vertical fin with slightly more area. The Boeing model 235 was not fitted with a NACA cowling, but rather the less efficient 'Townend' ring around the Pratt & Whitney Wasp radials cylinders. This aircraft was much used by both the Navy and the Army Air Corps in the late 1920's and early 1930's. The Army variation was known as the P-12E. The engine cowling was a British development known as the 'Townend' ring. It differed from the NACA cowling and was less effective in reducing the drag.

  2. Characteristics of potential repository wastes: Volume 4, Appendix 4A, Nuclear reactors at educational institutions of the United States; Appendix 4B, Data sheets for nuclear reactors at educational institutions; Appendix 4C, Supplemental data for Fort St. Vrain spent fuel; Appendix 4D, Supplemental data for Peach Bottom 1 spent fuel; Appendix 4E, Supplemental data for Fast Flux Test Facility

    SciTech Connect

    Not Available

    1992-07-01

    Volume 4 contains the following appendices: nuclear reactors at educational institutions in the United States; data sheets for nuclear reactors at educational institutions in the United States(operational reactors and shut-down reactors); supplemental data for Fort St. Vrain spent fuel; supplemental data for Peach Bottom 1 spent fuel; and supplemental data for Fast Flux Test Facility.

  3. Selective Phosphodiesterase 4B Inhibitors: A Review

    PubMed Central

    Azam, Mohammed Afzal; Tripuraneni, Naga Srinivas

    2014-01-01

    Abstract Phosphodiesterase 4B (PDE4B) is a member of the phosphodiesterase family of proteins that plays a critical role in regulating intracellular levels of cyclic adenosine monophosphate (cAMP) by controlling its rate of degradation. It has been demonstrated that this isoform is involved in the orchestra of events which includes inflammation, schizophrenia, cancers, chronic obstructive pulmonary disease, contractility of the myocardium, and psoriatic arthritis. Phosphodiesterase 4B has constituted an interesting target for drug development. In recent years, a number of PDE4B inhibitors have been developed for their use as therapeutic agents. In this review, an up-to-date status of the inhibitors investigated for the inhibition of PDE4B has been given so that this rich source of structural information of presently known PDE4B inhibitors could be helpful in generating a selective and potent inhibitor of PDE4B. PMID:25853062

  4. Familial C4B Deficiency and Immune Complex Glomerulonephritis

    PubMed Central

    Soto, K; Wu, YL; Ortiz, A; Aparício, SR; Yu, CY

    2010-01-01

    Homozygous complement C4B deficiency is described in a Southern European young female patient with Membranoproliferative Glomerulonephritis (MPGN) type III characterized by renal biopsies with strong complement C4 and IgG deposits. Low C4 levels were independent of clinical evolution or type of immunosuppression and were found in three other family members without renal disease or infections. HLA typing revealed that the patient has homozygous A*02, Cw*06, B*50 at the class I region, and DRB1*08 and DQB1*03 at the class II region. Genotypic and phenotypic studies demonstrated that the patient has homozygous monomodular RCCX in the HLA class III region, with single long C4A genes coding for C4A3 and complete C4B deficiency. Her father, mother, son and niece have heterozygous C4B deficiency. The patient’s deceased brother had a history of Henoch-Schönlein Purpura (HSP), an immune complex-mediated proliferative glomerulonephritis. These findings challenge the putative pathophysiological roles of C4A and C4B and underscore the need to perform functional assays, C4 allotyping and genotyping on patients with persistently low serum levels of a classical pathway complement component and glomerulopathy associated with immune deposits. PMID:20580617

  5. Familial C4B deficiency and immune complex glomerulonephritis.

    PubMed

    Soto, K; Wu, Y L; Ortiz, A; Aparício, S R; Yu, C Y

    2010-10-01

    Homozygous complement C4B deficiency is described in a Southern European young female patient with Membranoproliferative Glomerulonephritis (MPGN) type III characterized by renal biopsies with strong complement C4 and IgG deposits. Low C4 levels were independent of clinical evolution or type of immunosuppression and were found in three other family members without renal disease or infections. HLA typing revealed that the patient has homozygous A*02, Cw*06, B*50 at the class I region, and DRB1*08 and DQB1*03 at the class II region. Genotypic and phenotypic studies demonstrated that the patient has homozygous monomodular RCCX in the HLA class III region, with single long C4A genes coding for C4A3 and complete C4B deficiency. Her father, mother, son and niece have heterozygous C4B deficiency. The patient's deceased brother had a history of Henoch-Schönlein Purpura (HSP), an immune complex-mediated proliferative glomerulonephritis. These findings challenge the putative pathophysiological roles of C4A and C4B and underscore the need to perform functional assays, C4 allotyping and genotyping on patients with persistently low serum levels of a classical pathway complement component and glomerulopathy associated with immune deposits.

  6. RDR-4B doppler weather radar with forward looking wind shear detection capability

    NASA Technical Reports Server (NTRS)

    Grasley, Steven S.

    1992-01-01

    The topics are presented in viewgraph form and include the following: Bendix/King atmospheric transport and dispersion (ATAD) position; RDR-4A technical baseline; RTA-4A characteristics; RDR-4 antenna characteristics; modification of RDR-4A to RDR-4B; RDR-4A functional block diagram; RDR-4B characteristics; development/test plan; CV-580 testing capability; CV-580 test results; Continental A300 test configuration; Continental Data Recording Program operational considerations; Continental A300 test results; and display considerations.

  7. Cell Autonomous and Nonautonomous Function of CUL4B in Mouse Spermatogenesis*

    PubMed Central

    Yin, Yan; Liu, Liren; Yang, Chenyi; Lin, Congxing; Veith, George Michael; Wang, Caihong; Sutovsky, Peter; Zhou, Pengbo; Ma, Liang

    2016-01-01

    CUL4B ubiquitin ligase belongs to the cullin-RING ubiquitin ligase family. Although sharing many sequence and structural similarities, CUL4B plays distinct roles in spermatogenesis from its homologous protein CUL4A. We previously reported that genetic ablation of Cul4a in mice led to male infertility because of aberrant meiotic progression. In the present study, we generated Cul4b germ cell-specific conditional knock-out (Cul4bVasa),as well as Cul4b global knock-out (Cul4bSox2) mouse, to investigate its roles in spermatogenesis. Germ cell-specific deletion of Cul4b led to male infertility, despite normal testicular morphology and comparable numbers of spermatozoa. Notably, significantly impaired sperm mobility caused by reduced mitochondrial activity and glycolysis level were observed in the majority of the mutant spermatozoa, manifested by low, if any, sperm ATP production. Furthermore, Cul4bVasa spermatozoa exhibited defective arrangement of axonemal microtubules and flagella outer dense fibers. Our mass spectrometry analysis identified INSL6 as a novel CUL4B substrate in male germ cells, evidenced by its direct polyubiquination and degradation by CUL4B E3 ligase. Nevertheless, Cul4b global knock-out males lost their germ cells in an age-dependent manner, implying failure of maintaining the spermatogonial stem cell niche in somatic cells. Taken together, our results show that CUL4B is indispensable to spermatogenesis, and it functions cell autonomously in male germ cells to ensure spermatozoa motility, whereas it functions non-cell-autonomously in somatic cells to maintain spermatogonial stemness. Thus, CUL4B links two distinct spermatogenetic processes to a single E3 ligase, highlighting the significance of ubiquitin modification during spermatogenesis. PMID:26846852

  8. Pressure- and Additive-Mediated Sintering of B4C at Relatively Low Temperatures

    NASA Astrophysics Data System (ADS)

    Goswami, Ramasis; Qadri, Syed B.; Wollmershauser, James; Kolel-Veetil, Manoj K.; Feygelson, Boris

    2017-03-01

    A significant improvement in sinterability of B4C was achieved at a relatively low temperature by applying high pressure (2 GPa) and adding a small amount (5 wt pct) of Ni. The sintered B4C and Ni powder mixture showed improved hardness in the range of 21 to 32 GPa and improved modulus as compared to the sintered B4C powder without additive. This is mostly attributed to the formation of Ni4B3, as characterized by Reitveld refinement method and transmission electron microscopy (TEM), which enhances the bonding between B4C particles. These results provide a new avenue toward the development of sintering of B4C at relatively low temperatures (<0.5 T m of B4C).

  9. Pressure- and Additive-Mediated Sintering of B4C at Relatively Low Temperatures

    NASA Astrophysics Data System (ADS)

    Goswami, Ramasis; Qadri, Syed B.; Wollmershauser, James; Kolel-Veetil, Manoj K.; Feygelson, Boris

    2017-01-01

    A significant improvement in sinterability of B4C was achieved at a relatively low temperature by applying high pressure (2 GPa) and adding a small amount (5 wt pct) of Ni. The sintered B4C and Ni powder mixture showed improved hardness in the range of 21 to 32 GPa and improved modulus as compared to the sintered B4C powder without additive. This is mostly attributed to the formation of Ni4B3, as characterized by Reitveld refinement method and transmission electron microscopy (TEM), which enhances the bonding between B4C particles. These results provide a new avenue toward the development of sintering of B4C at relatively low temperatures (<0.5T m of B4C).

  10. Structural Basis for the Design of Selective Phosphodiesterase 4B Inhibitors

    PubMed Central

    Fox, David; Burgin, Alex B.; Gurney, Mark E.

    2014-01-01

    Phosphodiesterase-4B (PDE4B) regulates the pro-inflammatory Toll Receptor –Tumor Necrosis Factor α (TNFα) pathway in monocytes, macrophages and microglial cells. As such, it is an important, although under-exploited molecular target for anti-inflammatory drugs. This is due in part to the difficulty of developing selective PDE4B inhibitors as the amino acid sequence of the PDE4 active site is identical in all PDE4 subtypes (PDE4A-D). We show that highly selective PDE4B inhibitors can be designed by exploiting sequence differences outside the active site. Specifically, PDE4B selectivity can be achieved by capture of a C-terminal regulatory helix, now termed CR3 (Control Region 3), across the active site in a conformation that closes access by cAMP. PDE4B selectivity is driven by a single amino acid polymorphism in CR3 (Leu674 in PDE4B1 versus Gln594 in PDE4D). The reciprocal mutations in PDE4B and PDE4D cause a 70-80 fold shift in selectivity. Our structural studies show that CR3 is flexible and can adopt multiple orientations and multiple registries in the closed conformation. The new co-crystal structure with bound ligand provides a guide map for the design of PDE4B selective anti-inflammatory drugs. PMID:24361374

  11. Comparison of the Pharmacological Profiles of Selective PDE4B and PDE4D Inhibitors in the Central Nervous System

    PubMed Central

    Zhang, Chong; Xu, Ying; Zhang, Han-Ting; Gurney, Mark E.; O’Donnell, James M.

    2017-01-01

    Inhibition of cyclic AMP (cAMP)-specific phosphodiesterase 4 (PDE4) has been proposed as a potential treatment for a series of neuropsychological conditions such as depression, anxiety and memory loss. However, the specific involvement of each of the PDE4 subtypes (PDE4A, 4B and 4C) in different categories of behavior has yet to be elucidated. In the present study, we compared the possible pharmacological effects of PDE4B and PDE4D selective inhibitors, A-33 and D159687, in mediating neurological function in mice. Both compounds were equally potent in stimulating cAMP signaling in the mouse hippocampal cell line HT-22 leading to an increase in CREB phosphorylation. In contrast, A-33 and D159687 displayed distinct neuropharmacological effects in mouse behavioral tests. A-33 has an antidepressant-like profile as indicated by reduced immobility time in the forced swim and tail suspension tasks, as well as reduced latency to feed in the novelty suppressed feeding test. D159687, on the other hand, had a procognitive profile as it improved memory in the novel object recognition test but had no antidepressant or anxiolytic benefit. The present data suggests that inhibitors targeting specific subtypes of PDE4 may exhibit differential pharmacological effects and aid a more efficient pharmacotherapy towards neuropsychological conditions. PMID:28054669

  12. An assessment of the MCNP4C weight window

    SciTech Connect

    Christopher N. Culbertson; John S. Hendricks

    1999-12-01

    A new, enhanced weight window generator suite has been developed for MCNP version 4C. The new generator correctly estimates importances in either a user-specified, geometry-independent, orthogonal grid or in MCNP geometric cells. The geometry-independent option alleviates the need to subdivide the MCNP cell geometry for variance reduction purposes. In addition, the new suite corrects several pathologies in the existing MCNP weight window generator. The new generator is applied in a set of five variance reduction problems. The improved generator is compared with the weight window generator applied in MCNP4B. The benefits of the new methodology are highlighted, along with a description of its limitations. The authors also provide recommendations for utilization of the weight window generator.

  13. Cell Autonomous and Nonautonomous Function of CUL4B in Mouse Spermatogenesis.

    PubMed

    Yin, Yan; Liu, Liren; Yang, Chenyi; Lin, Congxing; Veith, George Michael; Wang, Caihong; Sutovsky, Peter; Zhou, Pengbo; Ma, Liang

    2016-03-25

    CUL4B ubiquitin ligase belongs to the cullin-RING ubiquitin ligase family. Although sharing many sequence and structural similarities, CUL4B plays distinct roles in spermatogenesis from its homologous protein CUL4A. We previously reported that genetic ablation ofCul4ain mice led to male infertility because of aberrant meiotic progression. In the present study, we generated Cul4bgerm cell-specific conditional knock-out (Cul4b(Vasa)),as well asCul4bglobal knock-out (Cul4b(Sox2)) mouse, to investigate its roles in spermatogenesis. Germ cell-specific deletion of Cul4bled to male infertility, despite normal testicular morphology and comparable numbers of spermatozoa. Notably, significantly impaired sperm mobility caused by reduced mitochondrial activity and glycolysis level were observed in the majority of the mutant spermatozoa, manifested by low, if any, sperm ATP production. Furthermore,Cul4b(Vasa)spermatozoa exhibited defective arrangement of axonemal microtubules and flagella outer dense fibers. Our mass spectrometry analysis identified INSL6 as a novel CUL4B substrate in male germ cells, evidenced by its direct polyubiquination and degradation by CUL4B E3 ligase. Nevertheless,Cul4bglobal knock-out males lost their germ cells in an age-dependent manner, implying failure of maintaining the spermatogonial stem cell niche in somatic cells. Taken together, our results show that CUL4B is indispensable to spermatogenesis, and it functions cell autonomously in male germ cells to ensure spermatozoa motility, whereas it functions non-cell-autonomously in somatic cells to maintain spermatogonial stemness. Thus, CUL4B links two distinct spermatogenetic processes to a single E3 ligase, highlighting the significance of ubiquitin modification during spermatogenesis.

  14. Accelerated hepatocellular carcinoma development in CUL4B transgenic mice.

    PubMed

    Yuan, Jupeng; Jiang, Baichun; Zhang, Aizhen; Qian, Yanyan; Tan, Haining; Gao, Jiangang; Shao, Changshun; Gong, Yaoqin

    2015-06-20

    Cullin 4B (CUL4B) is a component of the Cullin 4B-Ring E3 ligase (CRL4B) complex that functions in proteolysis and in epigenetic regulation. CUL4B possesses tumor-promoting properties and is markedly upregulated in many types of human cancers. To determine the role of CUL4B in liver tumorigenesis, we generated transgenic mice that expressed human CUL4B in livers and other tissues and evaluated the development of spontaneous and chemically-induced hepatocellular carcinomas. We observed that CUL4B transgenic mice spontaneously developed liver tumors at a high incidence at old ages and exhibited enhanced DEN-induced hepatocarcinogenesis. There was a high proliferation rate in the livers of CUL4B transgenic mice that was accompanied by increased levels of Cdk1, Cdk4 and cyclin D1 and decreased level of p16. The transgenic mice also exhibited increased compensatory proliferation after DEN-induced liver injury, which was accompanied by activation of Akt, Erk, p38 and NF-κB. We also found that Prdx3 was downregulated and that DEN induced a higher level of reactive oxygen species in the livers of transgenic mice. Together, our results demonstrate a critical role of CUL4B in hepatocarcinogenesis in mice.

  15. Variants in CUL4B are Associated with Cerebral Malformations

    PubMed Central

    Vulto-van Silfhout, Anneke T.; Nakagawa, Tadashi; Bahi-Buisson, Nadia; Haas, Stefan A.; Hu, Hao; Bienek, Melanie; Vissers, Lisenka E.L.M.; Gilissen, Christian; Tzschach, Andreas; Busche, Andreas; Müsebeck, Jörg; Rump, Patrick; Mathijssen, Inge B.; Avela, Kristiina; Somer, Mirja; Doagu, Fatma; Philips, Anju K.; Rauch, Anita; Baumer, Alessandra; Voesenek, Krysta; Poirier, Karine; Vigneron, Jacqueline; Amram, Daniel; Odent, Sylvie; Nawara, Magdalena; Obersztyn, Ewa; Lenart, Jacek; Charzewska, Agnieszka; Lebrun, Nicolas; Fischer, Ute; Nillesen, Willy M.; Yntema, Helger G.; Järvelä, Irma; Ropers, Hans-Hilger; de Vries, Bert B.A.; Brunner, Han G.; van Bokhoven, Hans; Raymond, F. Lucy; Willemsen, Michèl A.A.P.; Chelly, Jamel; Xiong, Yue; Barkovich, A. James; Kalscheuer, Vera M.; Kleefstra, Tjitske; de Brouwer, Arjan P.M.

    2015-01-01

    Variants in cullin 4B (CUL4B) are a known cause of syndromic X-linked intellectual disability. Here, we describe an additional 25 patients from 11 families with variants in CUL4B. We identified nine different novel variants in these families and confirmed the pathogenicity of all nontruncating variants. Neuroimaging data, available for 15 patients, showed the presence of cerebral malformations in ten patients. The cerebral anomalies comprised malformations of cortical development (MCD), ventriculomegaly, and diminished white matter volume. The phenotypic heterogeneity of the cerebral malformations might result from the involvement of CUL-4B in various cellular pathways essential for normal brain development. Accordingly, we show that CUL-4B interacts with WDR62, a protein in which variants were previously identified in patients with microcephaly and a wide range of MCD. This interaction might contribute to the development of cerebral malformations in patients with variants in CUL4B. PMID:25385192

  16. Variants in CUL4B are associated with cerebral malformations.

    PubMed

    Vulto-van Silfhout, Anneke T; Nakagawa, Tadashi; Bahi-Buisson, Nadia; Haas, Stefan A; Hu, Hao; Bienek, Melanie; Vissers, Lisenka E L M; Gilissen, Christian; Tzschach, Andreas; Busche, Andreas; Müsebeck, Jörg; Rump, Patrick; Mathijssen, Inge B; Avela, Kristiina; Somer, Mirja; Doagu, Fatma; Philips, Anju K; Rauch, Anita; Baumer, Alessandra; Voesenek, Krysta; Poirier, Karine; Vigneron, Jacqueline; Amram, Daniel; Odent, Sylvie; Nawara, Magdalena; Obersztyn, Ewa; Lenart, Jacek; Charzewska, Agnieszka; Lebrun, Nicolas; Fischer, Ute; Nillesen, Willy M; Yntema, Helger G; Järvelä, Irma; Ropers, Hans-Hilger; de Vries, Bert B A; Brunner, Han G; van Bokhoven, Hans; Raymond, F Lucy; Willemsen, Michèl A A P; Chelly, Jamel; Xiong, Yue; Barkovich, A James; Kalscheuer, Vera M; Kleefstra, Tjitske; de Brouwer, Arjan P M

    2015-01-01

    Variants in cullin 4B (CUL4B) are a known cause of syndromic X-linked intellectual disability. Here, we describe an additional 25 patients from 11 families with variants in CUL4B. We identified nine different novel variants in these families and confirmed the pathogenicity of all nontruncating variants. Neuroimaging data, available for 15 patients, showed the presence of cerebral malformations in ten patients. The cerebral anomalies comprised malformations of cortical development (MCD), ventriculomegaly, and diminished white matter volume. The phenotypic heterogeneity of the cerebral malformations might result from the involvement of CUL-4B in various cellular pathways essential for normal brain development. Accordingly, we show that CUL-4B interacts with WDR62, a protein in which variants were previously identified in patients with microcephaly and a wide range of MCD. This interaction might contribute to the development of cerebral malformations in patients with variants in CUL4B.

  17. PROCEEDINGS: 1993 SO2 CONTROL SYMPOSIUM - VOLUME 2. SESSIONS 4A, 4B, AND 5A

    EPA Science Inventory

    The report documents more than 100 presentations at the 1993 SO2 Control Symposium in Boston, MA, August 24-27, 1993. The presentations covered a wide range of topics: industry's strategies for dealing with Clean Air Act Amendments of 1990, including Phase I strategies, the emiss...

  18. High resolution crystal structure of human Dim2/TXNL4B

    Technology Transfer Automated Retrieval System (TEKTRAN)

    TXNL4A (thioredoxin like 4A) is an essential protein conserved from yeast to human and is a component of the pre-mRNA splicing machinery. TXNL4B was identified as a TXNL4 family protein that also interacts with prp6, an integral component of the U4/U6•U5 tri-snRNP complex, and was shown to function...

  19. Phosphorylation of mammalian initiation factor eIF-4B

    SciTech Connect

    Duncan, R.F.; Milburn, S.C.; Cooper, R.; Gould, K.; Hunter, T.; Hershey, J.W.B.

    1987-05-01

    The phosphorylation of initiation factors appears to be an important mechanism for regulating the rate of translation in mammalian cells. eIF-4B (80 kDa) purified from HeLa cells exhibits a complex array of 8 to 12 spots when analyzed by 2-dimensional isoelectric focusing - SDS polyacrylamide gel electrophoresis. A similar array of eIF-4B spots is seen when total lysate proteins are analyzed by immunoblotting with anti-eIF-4B antiserum or with antibodies affinity-purified from the most basic eIF-4B spot. The multiple forms of eIF-4B are due to phosphorylation, since all but the most basic spot are labeled with (/sup 32/P)phosphate in vivo and the action of alkaline phosphatase in vitro reduces the array to only two spots. Tryptic peptide maps of phosphopeptides from each of the various isoelectric variants of eIF-4B show a similar complexity, suggesting that a number of different sites are phosphorylated in a random order. When serum-deprived HeLa cells are treated with phorbol ester, both the protein synthesis rate and the extent of eIF-4B phosphorylation increase, suggesting that C kinase may be a regulator of translation. Purified C kinase phosphorylates a number of pure initiation factors in vitro, but eIF-4B is the strongest target protein. When pure eIF-4B is treated, the entire mass of eIF-4B is shifted to the most acidic spots, indicating very strong phosphorylation. Attempts are being made to detect differences in the in vitro activities of the non-phosphorylated and highly phosphorylated forms.

  20. Opposing Chromatin Signals Direct and Regulate the Activity of Lysine Demethylase 4C (KDM4C)*

    PubMed Central

    Pack, Lindsey R.; Yamamoto, Keith R.; Fujimori, Danica Galonić

    2016-01-01

    Histone H3 lysine 4 trimethylation (H3K4me3) and histone H3 lysine 9 trimethylation (H3K9me3) are epigenetic marks with opposing roles in transcription regulation. Whereas colocalization of these modifications is generally excluded in the genome, how this preclusion is established remains poorly understood. Lysine demethylase 4C (KDM4C), an H3K9me3 demethylase, localizes predominantly to H3K4me3-containing promoters through its hybrid tandem tudor domain (TTD) (1, 2), providing a model for how these modifications might be excluded. We quantitatively investigated the contribution of the TTD to the catalysis of H3K9me3 demethylation by KDM4C and demonstrated that TTD-mediated recognition of H3K4me3 stimulates demethylation of H3K9me3 in cis on peptide and mononucleosome substrates. Our findings support a multivalent interaction mechanism, by which an activating mark, H3K4me3, recruits and stimulates KDM4C to remove the repressive H3K9me3 mark, thus facilitating exclusion. In addition, our work suggests that differential TTD binding properties across the KDM4 demethylase family may differentiate their targets in the genome. PMID:26747609

  1. Category 4b - A Regulatory Alternative to TMDLs

    EPA Pesticide Factsheets

    The paper describes the extent to which states have successfully employed TMDL alternatives to address impaired waters and assigned these waters to Category 4b, and includes several Washington State examples.

  2. Nanog regulates primordial germ cell migration through Cxcr4b.

    PubMed

    Sánchez-Sánchez, Ana Virginia; Camp, Esther; Leal-Tassias, Aránzazu; Atkinson, Stuart P; Armstrong, Lyle; Díaz-Llopis, Manuel; Mullor, José L

    2010-09-01

    Gonadal development in vertebrates depends on the early determination of primordial germ cells (PGCs) and their correct migration to the sites where the gonads develop. Several genes have been implicated in PGC specification and migration in vertebrates. Additionally, some of the genes associated with pluripotency, such as Oct4 and Nanog, are expressed in PGCs and gonads, suggesting a role for these genes in maintaining pluripotency of the germ lineage, which may be considered the only cell type that perpetually maintains stemness properties. Here, we report that medaka Nanog (Ol-Nanog) is expressed in the developing PGCs. Depletion of Ol-Nanog protein causes aberrant migration of PGCs and inhibits expression of Cxcr4b in PGCs, where it normally serves as the receptor of Sdf1a to guide PGC migration. Moreover, chromatin immunoprecipitation analysis demonstrates that Ol-Nanog protein binds to the promoter region of Cxcr4b, suggesting a direct regulation of Cxcr4b by Ol-Nanog. Simultaneous overexpression of Cxcr4b mRNA and depletion of Ol-Nanog protein in PGCs rescues the migration defective phenotype induced by a loss of Ol-Nanog, whereas overexpression of Sdf1a, the ligand for Cxcr4b, does not restore proper PGC migration. These results indicate that Ol-Nanog mediates PGC migration by regulating Cxcr4b expression.

  3. KDM4C and ATF4 Cooperate in Transcriptional Control of Amino Acid Metabolism.

    PubMed

    Zhao, Erhu; Ding, Jane; Xia, Yingfeng; Liu, Mengling; Ye, Bingwei; Choi, Jeong-Hyeon; Yan, Chunhong; Dong, Zheng; Huang, Shuang; Zha, Yunhong; Yang, Liqun; Cui, Hongjuan; Ding, Han-Fei

    2016-01-26

    The histone lysine demethylase KDM4C is often overexpressed in cancers primarily through gene amplification. The molecular mechanisms of KDM4C action in tumorigenesis are not well defined. Here, we report that KDM4C transcriptionally activates amino acid biosynthesis and transport, leading to a significant increase in intracellular amino acid levels. Examination of the serine-glycine synthesis pathway reveals that KDM4C epigenetically activates the pathway genes under steady-state and serine deprivation conditions by removing the repressive histone modification H3 lysine 9 (H3K9) trimethylation. This action of KDM4C requires ATF4, a transcriptional master regulator of amino acid metabolism and stress responses. KDM4C activates ATF4 transcription and interacts with ATF4 to target serine pathway genes for transcriptional activation. We further present evidence for KDM4C in transcriptional coordination of amino acid metabolism and cell proliferation. These findings suggest a molecular mechanism linking KDM4C-mediated H3K9 demethylation and ATF4-mediated transactivation in reprogramming amino acid metabolism for cancer cell proliferation.

  4. KDM4C and ATF4 Cooperate in Transcriptional Control of Amino Acid Metabolism

    PubMed Central

    Xia, Yingfeng; Liu, Mengling; Ye, Bingwei; Choi, Jeong-Hyeon; Yan, Chunhong; Dong, Zheng; Huang, Shuang; Zha, Yunhong; Yang, Liqun; Cui, Hongjuan; Ding, Han-Fei

    2015-01-01

    SUMMARY The histone lysine demethylase KDM4C is often overexpressed in cancers primarily through gene amplification. The molecular mechanisms of KDM4C action in tumorigenesis are not well defined. Here we report that KDM4C transcriptionally activates amino acid biosynthesis and transport, leading to a significant increase in intracellular amino acid levels. Examination of the serine-glycine synthesis pathway reveals that KDM4C epigenetically activates the pathway genes under steady-state and serine deprivation conditions by removing the repressive histone modification H3 lysine 9 (H3K9) trimethylation. This action of KDM4C requires ATF4, a transcriptional master regulator of amino acid metabolism and stress responses. KDM4C activates ATF4 transcription and interacts with ATF4 to target serine pathway genes for transcriptional activation. We further present evidence for KDM4C in transcriptional coordination of amino acid metabolism and cell proliferation. These findings suggest a molecular mechanism linking KDM4C-mediated H3K9 demethylation and ATF4-mediated transactivation in reprogramming amino acid metabolism for cancer cell proliferation. PMID:26774480

  5. In resting COS1 cells a dominant negative approach shows that specific, anchored PDE4 cAMP phosphodiesterase isoforms gate the activation, by basal cyclic AMP production, of AKAP-tethered protein kinase A type II located in the centrosomal region.

    PubMed

    McCahill, Angela; McSorley, Theresa; Huston, Elaine; Hill, Elaine V; Lynch, Martin J; Gall, Irene; Keryer, Guy; Lygren, Birgitte; Tasken, Kjetil; van Heeke, Gino; Houslay, Miles D

    2005-09-01

    We employ a novel, dominant negative approach to identify a key role for certain tethered cyclic AMP specific phosphodiesterase-4 (PDE4) isoforms in regulating cyclic AMP dependent protein kinase A (PKA) sub-populations in resting COS1 cells. A fraction of PKA is clearly active in resting COS1 cells and this activity increases when cells are treated with the selective PDE4 inhibitor, rolipram. Point mutation of a critical, conserved aspartate residue in the catalytic site of long PDE4A4, PDE4B1, PDE4C2 and PDE4D3 isoforms renders them catalytically inactive. Overexpressed in resting COS1 cells, catalytically inactive forms of PDE4C2 and PDE4D3, but not PDE4A4 and PDE4B1, are constitutively PKA phosphorylated while overexpressed active versions of all these isoforms are not. Inactive and active versions of all these isoforms are PKA phosphorylated in cells where protein kinase A is maximally activated with forskolin and IBMX. By contrast, rolipram challenge of COS1 cells selectively triggers the PKA phosphorylation of recombinant, active PDE4D3 and PDE4C2 but not recombinant, active PDE4A4 and PDE4B1. Purified, recombinant PDE4D3 and PDE4A4 show a similar dose-dependency for in vitro phosphorylation by PKA. Disruption of the tethering of PKA type-II to PKA anchor proteins (AKAPs), achieved using the peptide Ht31, prevents inactive forms of PDE4C2 and PDE4D3 being constitutively PKA phosphorylated in resting cells as does siRNA-mediated knockdown of PKA-RII, but not PKA-RI. PDE4C2 and PDE4D3 co-immunoprecipitate from COS1 cell lysates with 250 kDa and 450 kDa AKAPs that tether PKA type-II and not PKA type-I. PKA type-II co-localises with AKAP450 in the centrosomal region of COS1 cells. The perinuclear distribution of recombinant, inactive PDE4D3, but not inactive PDE4A4, overlaps with AKAP450 and PKA type-II. The distribution of PKA phosphorylated inactive PDE4D3 also overlaps with that of AKAP450 in the centrosomal region of COS1 cells. We propose that a novel role

  6. MQ-4C Triton Unmanned Aircraft System (MQ-4C Triton)

    DTIC Science & Technology

    2015-12-01

    88% at a mission radius of 2,000 nm Level of Interoperability 1-5 BLOS and LOS from MOB / FOB (Land Based) MCS BLOS and LOS from MOB / FOB (Land...Based) MCS BLOS and LOS from the MOB (Land Based) MCS BLOS and LOS from MOB (Land Based) MCS (LOI 4 and 5) BLOS and LOS from MOB (Land Based...Mission Control System MOB - Main Operating Base nm - nautical miles UA - Unmanned Aircraft MQ-4C Triton December 2015 SAR March 23, 2016 15:26:01

  7. A Genetic Interaction between Hepatitis C Virus NS4B and NS3 Is Important for RNA Replication▿

    PubMed Central

    Paredes, Anne M.; Blight, Keril J.

    2008-01-01

    Hepatitis C virus (HCV) nonstructural protein 4B (NS4B), a poorly characterized integral membrane protein, is thought to function as a scaffold for replication complex assembly; however, functional interactions with the other HCV nonstructural proteins within this complex have not been defined. We report that a Con1 chimeric subgenomic replicon containing the NS4B gene from the closely related H77 isolate is defective for RNA replication in a transient assay, suggesting that H77 NS4B is unable to productively interact with the Con1 replication machinery. The H77 NS4B sequences that proved detrimental for Con1 RNA replication resided in the predicted N- and C-terminal cytoplasmic domains as well as the central transmembrane region. Selection for Con1 derivatives that could utilize the entire H77 NS4B or hybrid Con1-H77 NS4B proteins yielded mutants containing single amino acid substitutions in NS3 and NS4A. The second-site mutations in NS3 partially restored the replication of Con1 chimeras containing the N-terminal or transmembrane domains of H77 NS4B. In contrast, the deleterious H77-specific sequences in the C terminus of NS4B, which mapped to a cluster of four amino acids, were completely suppressed by second-site substitutions in NS3. Collectively, these results provide the first evidence for a genetic interaction between NS4B and NS3 important for productive HCV RNA replication. PMID:18715921

  8. Hypovalency--a kinetic-energy density description of a 4c-2e bond.

    PubMed

    Jacobsen, Heiko

    2009-06-07

    A bond descriptor based on the kinetic energy density, the localized-orbital locator (LOL), is used to characterize the nature of the chemical bond in electron deficient multi-center bonds. The boranes B(2)H(6), B(4)H(4), B(4)H(10), [B(6)H(6)](2-), and [B(6)H(7)](-) serve as prototypical examples of hypovalent 3c-2e and 4c-2e bonding. The kinetic energy density is derived from a set of Kohn-Sham orbitals obtained from pure density functional calculations (PBE/TZVP), and the topology of LOL is analyzed in terms of (3,-3) attractors (Gamma). The B-B-B and B-H-B 3c-2e, and the B-B-H-B 4c-2e bonding situations are defined by their own characteristic LOL profiles. The presence of one attractor in relation to the three or four atoms that are engaged in electron deficient bonding provides sufficient indication of the type of 3c-2e or 4c-2e bond present. For the 4c-2e bond in [B(6)H(7)](-) the LOL analysis is compared to results from an experimental QTAIM study.

  9. Pyrazolopyridines as potent PDE4B inhibitors: 5-Heterocycle SAR

    SciTech Connect

    Mitchell, Charlotte J.; Ballantine, Stuart P.; Coe, Diane M.; Cook, Caroline M.; Delves, Christopher J.; Dowle, Mike D.; Edlin, Chris D.; Hamblin, J. Nicole; Holman, Stuart; Johnson, Martin R.; Jones, Paul S.; Keeling, Sue E.; Kranz, Michael; Lindvall, Mika; Lucas, Fiona S.; Neu, Margarete; Solanke, Yemisi E.; Somers, Don O.; Trivedi, Naimisha A.; Wiseman, Joanne O.

    2012-05-03

    Following the discovery of 4-(substituted amino)-1-alkyl-pyrazolo[3,4-b]pyridine-5-carboxamides as potent and selective phosphodiesterase 4B inhibitors, [Hamblin, J. N.; Angell, T.; Ballentine, S., et al. Bioorg. Med. Chem. Lett.2008, 18, 4237] the SAR of the 5-position was investigated further. A range of substituted heterocycles showed good potencies against PDE4. Optimisation using X-ray crystallography and computational modelling led to the discovery of 16, with sub-nM inhibition of LPS-induced TNF-{alpha} production from isolated human peripheral blood mononuclear cells.

  10. MCNP4B{sup {trademark}} verification and validation

    SciTech Connect

    Hendricks, J.S.; Court, J.D.

    1996-08-01

    Several new features and bug fixes have been incorporated into the new release of MCNP. As required by the MCNP Software Quality Assurance Plan, these changes to the code and the test set are documented here for user reference. This document summarizes the new MCNP4B features and corrections, separated into major and minor groupings. Also included are a code cleanup section and a section delineating problems identified in LA-12839 which have not been corrected. Finally, we document the MCNP4B test set modifications and explain how test set coverage has been improved.

  11. RAMONA-4B code for BWR systems analysis

    SciTech Connect

    Cheng, H.S.; Rohatgi, U.S.

    1996-12-31

    The RAMONA-4B code is a coupled thermal-hydraulic, 3D kinetics code for plant transient analyses of a complete Boiling Water Reactor (BWR) system including Reactor Pressure Vessel (RPV), Balance of Plant (BOP) and containment. The complete system representation enables an integrated and coupled systems analysis of a BWR without recourse to prescribed boundary conditions.

  12. Discovery of Dengue Virus NS4B Inhibitors

    PubMed Central

    Wang, Qing-Yin; Dong, Hongping; Zou, Bin; Karuna, Ratna; Wan, Kah Fei; Zou, Jing; Susila, Agatha; Yip, Andy; Shan, Chao; Yeo, Kim Long; Xu, Haoying; Ding, Mei; Chan, Wai Ling; Gu, Feng; Seah, Peck Gee; Liu, Wei; Lakshminarayana, Suresh B.; Kang, CongBao; Lescar, Julien; Blasco, Francesca; Smith, Paul W.

    2015-01-01

    ABSTRACT The four serotypes of dengue virus (DENV-1 to -4) represent the most prevalent mosquito-borne viral pathogens in humans. No clinically approved vaccine or antiviral is currently available for DENV. Here we report a spiropyrazolopyridone compound that potently inhibits DENV both in vitro and in vivo. The inhibitor was identified through screening of a 1.8-million-compound library by using a DENV-2 replicon assay. The compound selectively inhibits DENV-2 and -3 (50% effective concentration [EC50], 10 to 80 nM) but not DENV-1 and -4 (EC50, >20 μM). Resistance analysis showed that a mutation at amino acid 63 of DENV-2 NS4B (a nonenzymatic transmembrane protein and a component of the viral replication complex) could confer resistance to compound inhibition. Genetic studies demonstrate that variations at amino acid 63 of viral NS4B are responsible for the selective inhibition of DENV-2 and -3. Medicinal chemistry improved the physicochemical properties of the initial “hit” (compound 1), leading to compound 14a, which has good in vivo pharmacokinetics. Treatment of DENV-2-infected AG129 mice with compound 14a suppressed viremia, even when the treatment started after viral infection. The results have proven the concept that inhibitors of NS4B could potentially be developed for clinical treatment of DENV infection. Compound 14a represents a potential preclinical candidate for treatment of DENV-2- and -3-infected patients. IMPORTANCE Dengue virus (DENV) threatens up to 2.5 billion people and is now spreading in many regions in the world where it was not previously endemic. While there are several promising vaccine candidates in clinical trials, approved vaccines or antivirals are not yet available. Here we describe the identification and characterization of a spiropyrazolopyridone as a novel inhibitor of DENV by targeting the viral NS4B protein. The compound potently inhibits two of the four serotypes of DENV (DENV-2 and -3) both in vitro and in vivo. Our

  13. Characterization of Nuclear Localization Signal in the N Terminus of CUL4B and Its Essential Role in Cyclin E Degradation and Cell Cycle Progression*

    PubMed Central

    Zou, Yongxin; Mi, Jun; Cui, Jinpeng; Lu, Defen; Zhang, Xiyu; Guo, Chenhong; Gao, Guimin; Liu, Qiji; Chen, Bingxi; Shao, Changshun; Gong, Yaoqin

    2009-01-01

    CUL4A and CUL4B, which are derived from the same ancestor, CUL4, encode scaffold proteins that organize cullin-RING ubiquitin ligase (E3) complexes. Recent genetic studies have shown that germ line mutation in CUL4B can cause mental retardation, short stature, and other abnormalities in humans. CUL4A was observed to be overexpressed in breast and hepatocellular cancers, although no germ line mutation in human CUL4A has been reported. Although CUL4A has been known to be involved in a number of cellular processes, including DNA repair and cell cycle regulation, little is known about whether CUL4B has similar functions. In this report, we tested the functional importance of CUL4B in cell proliferation and characterized the nuclear localization signal (NLS) that is essential for its function. We found that RNA interference silencing of CUL4B led to an inhibition of cell proliferation and a prolonged S phase, due to the overaccumulation of cyclin E, a substrate targeted by CUL4B for ubiquitination. We showed that, unlike CUL4A and other cullins that carry their NLS in their C termini, NLS in CUL4B is located in its N terminus, between amino acid 37 and 40, KKRK. This NLS could bind to importin α1, α3, and α5. NLS-deleted CUL4B was distributed in cytoplasm and failed to promote cell proliferation. Therefore, the nuclear localization of CUL4B mediated by NLS is critical for its normal function in cell proliferation. PMID:19801544

  14. A region rich in aspartic acid, arginine, tyrosine, and glycine (DRYG) mediates eukaryotic initiation factor 4B (eIF4B) self-association and interaction with eIF3.

    PubMed Central

    Méthot, N; Song, M S; Sonenberg, N

    1996-01-01

    The binding of mRNA to the ribosome is mediated by eukaryotic initiation factors eukaryotic initiation factor 4F (eIF4F), eIF4B, eIF4A, and eIF3, eIF4F binds to the mRNA cap structure and, in combination with eIF4B, is believed to unwind the secondary structure in the 5' untranslated region to facilitate ribosome binding. eIF3 associates with the 40S ribosomal subunit prior to mRNA binding. eIF4B copurifies with eIF3 and eIF4F through several purification steps, suggesting the involvement of a multisubunit complex during translation initiation. To understand the mechanism by which eIF4B promotes 40S ribosome binding to the mRNA, we studied its interactions with partner proteins by using a filter overlay (protein-protein [far Western]) assay and the two-hybrid system. In this report, we show that eIF4B self-associates and also interacts directly with the p170 subunit of eIF3. A region rich in aspartic acid, arginine, tyrosine, and glycine, termed the DRYG domain, is sufficient for self-association of eIF4B, both in vitro and in vivo, and for interaction with the p170 subunit of eIF3. These experiments suggest that eIF4B participates in mRNA-ribosome binding by acting as an intermediary between the mRNA and eIF3, via a direct interaction with the p170 subunit of eIF3. PMID:8816444

  15. Generation and characterization of a Cyp4b1 null mouse and the role of CYP4B1 in the activation and toxicity of Ipomeanol.

    PubMed

    Parkinson, Oliver T; Liggitt, H Denny; Rettie, Allan E; Kelly, Edward J

    2013-08-01

    4-Ipomeanol (IPO) is a prototypical pulmonary toxin that requires P450-mediated metabolic activation to reactive intermediates in order to elicit its toxic effects. CYP4B1 is a pulmonary enzyme that has been shown, in vitro, to have a high capacity for bioactivating IPO. In order to determine, unambiguously, the role of CYP4B1 in IPO bioactivation in vivo, we generated Cyp4b1 null mice following targeted disruption of the gene downstream of exon 1. Cyp4b1 (-/-) mice are viable and healthy, with no overt phenotype, and no evidence of compensatory upregulation of other P450 isoforms in any of the tissues examined. Pulmonary and renal microsomes prepared from male Cyp4b1 (-/-) mice exhibited no detectable expression of the protein and catalyzed the in vitro bioactivation of IPO at < 10% of the rates observed in tissue microsomes from Cyp4b1 (+/+) animals. Administration of IPO (20mg/kg) to Cyp4b1 (+/+) mice resulted in characteristic lesions in the lung, and to a lesser extent in the kidney, which were completely absent in Cyp4b1 (-/-) mice. We conclude that CYP4B1 is a critical enzyme for the bioactivation of IPO in vivo and that the Cyp4b1 (-/-) mouse is a useful model for studying CYP4B1-dependent metabolism and toxicity.

  16. SECONDARY ECLIPSE PHOTOMETRY OF WASP-4b WITH WARM SPITZER

    SciTech Connect

    Beerer, Ingrid M.; Knutson, Heather A.; Burrows, Adam; Fortney, Jonathan J.; Laughlin, Gregory; Agol, Eric; Cowan, Nicolas B.; Charbonneau, David; Desert, Jean-Michel; Deming, Drake; Langton, Jonathan; Lewis, Nikole K.; Showman, Adam P.

    2011-01-20

    We present photometry of the giant extrasolar planet WASP-4b at 3.6 and 4.5 {mu}m taken with the Infrared Array Camera on board the Spitzer Space Telescope as part of Spitzer's extended warm mission. We find secondary eclipse depths of 0.319% {+-} 0.031% and 0.343% {+-} 0.027% for the 3.6 and 4.5 {mu}m bands, respectively, and show model emission spectra and pressure-temperature profiles for the planetary atmosphere. These eclipse depths are well fit by model emission spectra with water and other molecules in absorption, similar to those used for TrES-3 and HD 189733b. Depending on our choice of model, these results indicate that this planet has either a weak dayside temperature inversion or no inversion at all. The absence of a strong thermal inversion on this highly irradiated planet is contrary to the idea that highly irradiated planets are expected to have inversions, perhaps due the presence of an unknown absorber in the upper atmosphere. This result might be explained by the modestly enhanced activity level of WASP-4b's G7V host star, which could increase the amount of UV flux received by the planet, therefore reducing the abundance of the unknown stratospheric absorber in the planetary atmosphere as suggested in Knutson et al. We also find no evidence for an offset in the timing of the secondary eclipse and place a 2{sigma} upper limit on |ecos {omega}| of 0.0024, which constrains the range of tidal heating models that could explain this planet's inflated radius.

  17. Homologous Transcription Factors DUX4 and DUX4c Associate with Cytoplasmic Proteins during Muscle Differentiation

    PubMed Central

    Ansseau, Eugénie; Matteotti, Christel; Yip, Cassandre; Liu, Jian; Leroy, Baptiste; Hubeau, Céline; Gerbaux, Cécile; Cloet, Samuel; Wauters, Armelle; Zorbo, Sabrina; Meyer, Pierre; Pirson, Isabelle; Laoudj-Chenivesse, Dalila; Wattiez, Ruddy; Harper, Scott Q.; Belayew, Alexandra; Coppée, Frédérique

    2016-01-01

    Hundreds of double homeobox (DUX) genes map within 3.3-kb repeated elements dispersed in the human genome and encode DNA-binding proteins. Among these, we identified DUX4, a potent transcription factor that causes facioscapulohumeral muscular dystrophy (FSHD). In the present study, we performed yeast two-hybrid screens and protein co-purifications with HaloTag-DUX fusions or GST-DUX4 pull-down to identify protein partners of DUX4, DUX4c (which is identical to DUX4 except for the end of the carboxyl terminal domain) and DUX1 (which is limited to the double homeodomain). Unexpectedly, we identified and validated (by co-immunoprecipitation, GST pull-down, co-immunofluorescence and in situ Proximal Ligation Assay) the interaction of DUX4, DUX4c and DUX1 with type III intermediate filament protein desmin in the cytoplasm and at the nuclear periphery. Desmin filaments link adjacent sarcomere at the Z-discs, connect them to sarcolemma proteins and interact with mitochondria. These intermediate filament also contact the nuclear lamina and contribute to positioning of the nuclei. Another Z-disc protein, LMCD1 that contains a LIM domain was also validated as a DUX4 partner. The functionality of DUX4 or DUX4c interactions with cytoplasmic proteins is underscored by the cytoplasmic detection of DUX4/DUX4c upon myoblast fusion. In addition, we identified and validated (by co-immunoprecipitation, co-immunofluorescence and in situ Proximal Ligation Assay) as DUX4/4c partners several RNA-binding proteins such as C1QBP, SRSF9, RBM3, FUS/TLS and SFPQ that are involved in mRNA splicing and translation. FUS and SFPQ are nuclear proteins, however their cytoplasmic translocation was reported in neuronal cells where they associated with ribonucleoparticles (RNPs). Several other validated or identified DUX4/DUX4c partners are also contained in mRNP granules, and the co-localizations with cytoplasmic DAPI-positive spots is in keeping with such an association. Large muscle RNPs were

  18. Calorimetric measurements on Li{sub 4}C{sub 60} and Na{sub 4}C{sub 60}

    SciTech Connect

    Inaba, Akira; Miyazaki, Yuji; Michałowski, Paweł P.; Gracia-Espino, Eduardo; Wågberg, Thomas; Sundqvist, Bertil

    2015-04-28

    We show specific heat data for Na{sub 4}C{sub 60} and Li{sub 4}C{sub 60} in the range 0.4-350 K for samples characterized by Raman spectroscopy and X-ray diffraction. At high temperatures, the two different polymer structures have very similar specific heats both in absolute values and in general trend. The specific heat data are compared with data for undoped polymeric and pristine C{sub 60}. At high temperatures, a difference in specific heat between the intercalated and undoped C{sub 60} polymers of 100 J K{sup −1} mol{sup −1} is observed, in agreement with the Dulong-Petit law. At low temperatures, the specific heat data for Li{sub 4}C{sub 60} and Na{sub 4}C{sub 60} are modified by the stiffening of vibrational and librational molecular motion induced by the polymer bonds. The covalent twin bonds in Li{sub 4}C{sub 60} affect these motions to a somewhat higher degree than the single intermolecular bonds in Na{sub 4}C{sub 60}. Below 1 K, the specific heats of both materials become linear in temperature, as expected from the effective dimensionality of the structure. The contribution to the total specific heat from the inserted metal ions can be well described by Einstein functions with T{sub E} = 386 K for Li{sub 4}C{sub 60} and T{sub E} = 120 K for Na{sub 4}C{sub 60}, but for both materials we also observe a Schottky-type contribution corresponding to a first approximation to a two-level system with ΔE = 9.3 meV for Li{sub 4}C{sub 60} and 3.1 meV for Na{sub 4}C{sub 60}, probably associated with jumps between closely spaced energy levels inside “octahedral-type” ionic sites. Static magnetic fields up to 9 T had very small effects on the specific heat below 10 K.

  19. Chromosome Conformation Capture on Chip (4C): Data Processing.

    PubMed

    Leblanc, Benjamin; Comet, Itys; Bantignies, Frédéric; Cavalli, Giacomo

    2016-01-01

    4C methods are useful to investigate dependencies between regulatory mechanisms and chromatin structures by revealing the frequency of chromatin contacts between a locus of interest and remote sequences on the chromosome. In this chapter we describe a protocol for the data analysis of microarray-based 4C experiments, presenting updated versions of the methods we used in a previous study of the large-scale chromatin interaction profile of a Polycomb response element in Drosophila. The protocol covers data preparation, normalization, microarray probe selection, and the multi-resolution detection of regions with enriched chromatin contacts. A reanalysis of two independent mouse datasets illustrates the versatility of this protocol and the importance of data processing in 4C. Methods were implemented in the R package MRA.TA (Multi-Resolution Analyses on Tiling Array data), and they can be used to analyze ChIP-on-chip data on broadly distributed chromatin components such as histone marks.

  20. B{sub 4}C thin films for neutron detection

    SciTech Connect

    Hoeglund, Carina; Birch, Jens; Jensen, Jens; Hultman, Lars; Andersen, Ken; Hall-Wilton, Richard; Bigault, Thierry; Buffet, Jean-Claude; Correa, Jonathan; Esch, Patrick van; Guerard, Bruno; Piscitelli, Francesco; Khaplanov, Anton; Vettier, Christian; Vollenberg, Wilhelmus

    2012-05-15

    Due to the very limited availability of {sup 3}He, new kinds of neutron detectors, not based on {sup 3}He, are urgently needed. Here, we present a method to produce thin films of {sup 10}B{sub 4}C, with maximized detection efficiency, intended to be part of a new generation of large area neutron detectors. B{sub 4}C thin films have been deposited onto Al-blade and Si wafer substrates by dc magnetron sputtering from {sup nat}B{sub 4}C and {sup 10}B{sub 4}C targets in an Ar discharge, using an industrial deposition system. The films were characterized with scanning electron microscopy, elastic recoil detection analysis, x-ray reflectivity, and neutron radiography. We show that the film-substrate adhesion and film purity are improved by increased substrate temperature and deposition rate. A deposition rate of 3.8 A/s and substrate temperature of 400 deg. C result in films with a density close to bulk values and good adhesion to film thickness above 3 {mu}m. Boron-10 contents of almost 80 at. % are obtained in 6.3 m{sup 2} of 1 {mu}m thick {sup 10}B{sub 4}C thin films coated on Al-blades. Initial neutron absorption measurements agree with Monte Carlo simulations and show that the layer thickness, number of layers, neutron wavelength, and amount of impurities are determining factors. The study also shows the importance of having uniform layer thicknesses over large areas, which for a full-scale detector could be in total {approx}1000 m{sup 2} of two-side coated Al-blades with {approx}1 {mu}m thick {sup 10}B{sub 4}C films.

  1. Compact binary evolutions with the Z4c formulation

    NASA Astrophysics Data System (ADS)

    Hilditch, David; Bernuzzi, Sebastiano; Thierfelder, Marcus; Cao, Zhoujian; Tichy, Wolfgang; Brügmann, Bernd

    2013-10-01

    Numerical relativity simulations of compact binaries with the Z4c and Baumgarte-Shapiro-Shibata-Nakamura-Oohara-Kojima (BSSNOK) formulations are compared. The Z4c formulation is advantageous in every case considered. In simulations of nonvacuum spacetimes, the constraint violations due to truncation errors are between 1 and 3 orders of magnitude lower in the Z4c evolutions. Improvements are also found in the accuracy of the computed gravitational radiation. For equal-mass irrotational binary neutron star evolutions, we find that the absolute errors in phase and amplitude of the waveforms can be up to a factor of 4 smaller. The quality of the Z4c numerical data is also demonstrated by a remarkably accurate computation of the Arnowitt-Deser-Misner mass from surface integrals. For equal-mass nonspinning binary puncture black hole evolutions, we find that the absolute errors in phase and amplitude of the waveforms can be up to a factor of 2 smaller. In the same evolutions, we find that away from the punctures the Hamiltonian constraint violation is reduced by between 1 and 2 orders of magnitude. Furthermore, the utility of gravitational radiation controlling, constraint preserving boundary conditions for the Z4c formulation is demonstrated. The evolution of spacetimes containing a single compact object confirms earlier results in spherical symmetry. The boundary conditions avoid spurious and nonconvergent effects present in high resolution runs with either formulation with a more naive boundary treatment. We conclude that Z4c is preferable to BSSNOK for the numerical solution of the 3+1 Einstein equations with the puncture gauge.

  2. The deformation of B4C particle in the B4C/2024Al composites after high velocity impact.

    PubMed

    Zhou, Zhisong; Wu, Gaohui; Jiang, Longtao; Xu, Zhongguo

    2014-12-01

    In the present work, B4C/2024Al composites with volume fraction of 45% were prepared by a pressure infiltration method. The microstructure of the crater bottom of B4C/2024Al composite after impact was characterized by transmission electron microscope (TEM), which indicated that recovery and dynamic recrystallization generated in Al matrix, and the grain size distribution was about from dozens of nanometer to 200 nm. Furthermore, the plastic deformation was observed in B4C ceramic, which led to the transformation from monocrystal to polycrystal ceramic grains. The boundary observed in this work was high-angle grain boundary and the two grains at the boundary had an orientation difference of 30°.

  3. Electron photon verification calculations using MCNP4B

    SciTech Connect

    Gierga, D.P.; Adams, K.J.

    1998-07-01

    MCNP4B was released in February 1997 with significant enhancements to electron/photon transport methods. These enhancements have been verified against a wide range of published electron/photon experiments, spanning high energy bremsstrahlung production to electron transmission and reflection. Three sets of bremsstrahlung experiments were simulated. The first verification calculations for bremsstrahlung production used the experimental results in Faddegon for 15 MeV electrons incident on lead, aluminum, and beryllium targets. The calculated integrated bremsstrahlung yields, the bremsstrahlung energy spectra, and the mean energy of the bremsstrahlung beam were compared with experiment. The impact of several MCNP tally options and physics parameters was explored in detail. The second was the experiment of O`Dell which measured the bremsstrahlung spectra from 10 and 20.9 MeV electrons incident on a gold/tungsten target. The final set was a comparison of relative experimental spectra with calculated results for 9.66 MeV electrons incident on tungsten based on the experiment of Starfelt and Koch. The transmission experiments of Ebert were also studied, including comparisons of transmission coefficients for 10.2 MeV electrons incident on carbon, silver, and uranium foils. The agreement between experiment and simulation was usually within two standard deviations of the experimental and calculational errors.

  4. Proper Motion of Components in 4C 39.25

    NASA Technical Reports Server (NTRS)

    Guirado, J. C.; Marcaide, J. M.; Alberdi, A.; Elosegui, P.; Ratner, M. I.; Shapiro, I. I.; Kilger, R.; Mantovani, F.; Venturi, T.; Rius, A.; Ros, E.; Trigilio, C.; Whitney, A. R.

    1995-01-01

    From a series of simultaneous 8.4 and 2.3 GHz VLBI observations of the quasar 4C 39.25 phase referenced to the radio source 0920+390, carried out in 1990-1992, we have measured the proper motion of component b in 4C 39.25: mu(sub alpha) = 90 +/- 43 (mu)as/yr, mu(sub beta) = 7 +/- 68 (mu)as/yr, where the quoted uncertainties account for the contribution of the statistical standard deviation and the errors assumed for the parameters related to the geometry of the interferometric array, the atmosphere, and the source structure. This proper motion is consistent with earlier interpretations of VLBI hybrid mapping results, which showed an internal motion of this component with respect to other structural components. Our differential astrometry analyses show component b to be the one in motion. Our results thus further constrain models of this quasar.

  5. 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Specification 4B welded or brazed steel cylinders... FOR PACKAGINGS Specifications for Cylinders § 178.50 Specification 4B welded or brazed steel cylinders. (a) Type, size, and service pressure. A DOT 4B is a welded or brazed steel cylinder with...

  6. 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Specification 4B welded or brazed steel cylinders... FOR PACKAGINGS Specifications for Cylinders § 178.50 Specification 4B welded or brazed steel cylinders. (a) Type, size, and service pressure. A DOT 4B is a welded or brazed steel cylinder with...

  7. 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Specification 4B welded or brazed steel cylinders... FOR PACKAGINGS Specifications for Cylinders § 178.50 Specification 4B welded or brazed steel cylinders. (a) Type, size, and service pressure. A DOT 4B is a welded or brazed steel cylinder with...

  8. 49 CFR 178.50 - Specification 4B welded or brazed steel cylinders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Specification 4B welded or brazed steel cylinders... FOR PACKAGINGS Specifications for Cylinders § 178.50 Specification 4B welded or brazed steel cylinders. (a) Type, size, and service pressure. A DOT 4B is a welded or brazed steel cylinder with...

  9. Navy Officials Justified the MQ-4C Triton Procurement Quantity

    DTIC Science & Technology

    2015-09-16

    Visit us at www.dodig.mil September 16, 2015 Objective This is the first in a series of audits on the Navy MQ-4C Triton (Triton) Unmanned Aircraft...System (UAS) Program. Our overall objective for the series of audits was to determine whether the Navy effectively managed the Triton UAS...acquisition program. For this audit , we determined whether the Navy adequately justified the overall Triton Unmanned Aircraft procurement quantity

  10. Determinants of the tumor suppressor INPP4B protein and lipid phosphatase activities.

    PubMed

    Lopez, Sandra M; Hodgson, Myles C; Packianathan, Charles; Bingol-Ozakpinar, Ozlem; Uras, Fikriye; Rosen, Barry P; Agoulnik, Irina U

    2013-10-18

    The tumor suppressor INPP4B is an important regulator of phosphatidyl-inositol signaling in the cell. Reduced INPP4B expression is associated with poor outcomes for breast, prostate, and ovarian cancer patients. INPP4B contains a CX5R catalytic motif characteristic of dual-specificity phosphatases, such as PTEN. Lipid phosphatase activity of INPP4B has previously been described. In this report we show that INPP4B can dephosphorylate para-nitrophenyl phosphate (pNPP) and 6,8-difluoro-4-methylumbelliferyl (DiFMUP), synthetic phosphotyrosine analogs, suggesting that INPP4B has protein tyrosine phosphatase (PTP) activity. Using mutagenesis, we examined the functional role of specific amino acids within the INPP4B C842KSAKDR catalytic site. The K843M mutant displayed increased pNPP hydrolysis, the K846M mutant lost lipid phosphatase activity with no effect on PTP activity, and the D847E substitution ablated PTP activity and significantly reduced lipid phosphatase activity. Further, we show that INPP4B but not PTEN is able to reduce tyrosine phosphorylation of Akt1 and both the lipid and PTP activity of INPP4B likely contribute to the reduction of Akt1 phosphorylation. Taken together our data identified key residues in the INPP4B catalytic domain associated with lipid and protein phosphatase activities and found a robust downstream target regulated by INPP4B but not PTEN.

  11. The HMG-box transcription factor Sox4b is required for pituitary expression of gata2a and specification of thyrotrope and gonadotrope cells in zebrafish.

    PubMed

    Quiroz, Yobhana; Lopez, Mauricio; Mavropoulos, Anastasia; Motte, Patrick; Martial, Joseph A; Hammerschmidt, Matthias; Muller, Marc

    2012-06-01

    The pituitary is a complex gland comprising different cell types each secreting specific hormones. The extensive network of signaling molecules and transcription factors required for determination and terminal differentiation of specific cell types is still not fully understood. The SRY-like HMG-box (SOX) transcription factor Sox4 plays important roles in many developmental processes and has two homologs in zebrafish, Sox4a and Sox4b. We show that the sox4b gene is expressed in the pituitary anlagen starting at 24 h after fertilization (hpf) and later in the entire head region including the pituitary. At 48 hpf, sox4b mRNA colocalizes with that for TSH (tshβ), glycoprotein subunit α (gsuα), and the Zn finger transcription factor Gata2a. Loss of Sox4b function, using morpholino knockdown or expression of a dominant-negative Sox4 mutant, leads to a drastic decrease in tshβ and gsuα expression and reduced levels of gh, whereas other anterior pituitary gland markers including prl, slβ, pomc, and lim3 are not affected. Sox4b is also required for expression of gata2a in the pituitary. Knockdown of gata2a leads to decreased tshβ and gsuα expression at 48 hpf, similar to sox4b morphants. Injection of gata2a mRNA into sox4b morphants rescued tshβ and gsuα expression in thyrotrope cells. Finally, sox4b or gata2a knockdown causes a significant decrease of gonadotropin expression (lhβ and fshβ) at 4 d after fertilization. In summary, our results indicate that Sox4b is expressed in zebrafish during pituitary development and plays a crucial role in the differentiation of thyrotrope and gonadotrope cells through induction of gata2a expression in the developing pituitary.

  12. Dosimetrical evaluation of Leksell Gamma Knife 4C radiosurgery unit

    NASA Astrophysics Data System (ADS)

    Sajeev, Thomas; Mustafa, Mohamed M.; Supe, Sanjay S.

    2011-01-01

    A number of experiments was performed using standard protocols, in order to evaluate the dosimetric accuracy of Leksell Gamma Knife 4C unit. Verification of the beam alignment has been performed for all collimators using solid plastic head phantom and Gafchromic™ type MD-55 films. The study showed a good agreement of Leksell Gammaplan calculated dose profiles with experimentally determined profiles in all three axes. Isocentric accuracy is verified using a specially machined cylindrical aluminium film holder tool made with very narrow geometric tolerances aligned between trunnions of 4 mm collimator. Considering all uncertainties in all three dimensions, the estimated accuracy of the unit was 0.1 mm. Dose rate at the centre point of the unit has been determined according to the IAEA, TRS-398 protocol, using Unidose-E (PTW-Freiburg, Germany) with a 0.125 cc ion chamber, over a period of 6 years. The study showed that the Leksell Gamma Knife 4C unit is excellent radiosurgical equipment with high accuracy and precision, which makes it possible to deliver larger doses of radiation, within the limits defined by national and international guidelines, applicable for stereotactic radiosurgery procedures.

  13. Electronic and ionic conductivities in superionic Li4C60

    NASA Astrophysics Data System (ADS)

    Quintavalle, D.; Márkus, B. G.; Jánossy, A.; Simon, F.; Klupp, G.; Győri, M. A.; Kamarás, K.; Magnani, G.; Pontiroli, D.; Riccò, M.

    2016-05-01

    The 10 GHz microwave conductivity, σ (T ) and high field, 222 GHz electron spin resonance (HF-ESR) of Li4C60 fulleride is measured in a wide temperature range. We suggest that the majority of ESR active sites and at least some of the charge carriers for σ (T ) are electrons bound to a small concentration of surplus or vacancy ions in the polymer phase. Both σ (T ) and the ESR line shape depend on ionic motion. A change of the activation energy of σ (T ) at 125 K coincides with the onset of the ionic DC conductivity. The ESR line shape is determined mainly by Li ionic motion within octahedral voids below 150 K. At higher temperatures, fluctuations due to ionic diffusion change the environment of defects from axial to effectively isotropic on the ESR time scale. σ (T ) data up to 700 K through the depolymerization transition confirm that the monomeric phase of Li4C60 is a metal.

  14. Androgen Receptor Coactivator ARID4B Is Required for the Function of Sertoli Cells in Spermatogenesis.

    PubMed

    Wu, Ray-Chang; Zeng, Yang; Pan, I-Wen; Wu, Mei-Yi

    2015-09-01

    Defects in spermatogenesis, a process that produces spermatozoa inside seminiferous tubules of the testis, result in male infertility. Spermatogenic progression is highly dependent on a microenvironment provided by Sertoli cells, the only somatic cells and epithelium of seminiferous tubules. However, genes that regulate such an important activity of Sertoli cells are poorly understood. Here, we found that AT-rich interactive domain 4B (ARID4B), is essential for the function of Sertoli cells to regulate spermatogenesis. Specifically, we generated Sertoli cell-specific Arid4b knockout (Arid4bSCKO) mice, and showed that the Arid4bSCKO male mice were completely infertile with impaired testis development and significantly reduced testis size. Importantly, severe structural defects accompanied by loss of germ cells and Sertoli cell-only phenotype were found in many seminiferous tubules of the Arid4bSCKO testes. In addition, maturation of Sertoli cells was significantly delayed in the Arid4bSCKO mice, associated with delayed onset of spermatogenesis. Spermatogenic progression was also defective, showing an arrest at the round spermatid stage in the Arid4bSCKO testes. Interestingly, we showed that ARID4B functions as a "coactivator" of androgen receptor and is required for optimal transcriptional activation of reproductive homeobox 5, an androgen receptor target gene specifically expressed in Sertoli cells and critical for spermatogenesis. Together, our study identified ARID4B to be a key regulator of Sertoli cell function important for male germ cell development.

  15. BPO4@B2O3 and (BPO4@B2O3):Eu3+: The novel single-emitting-component phosphors for near UV-white LEDs

    NASA Astrophysics Data System (ADS)

    Cao, Xiyu; Liu, Wei; Jiang, Yu; Cao, Lixin; Su, Ge; Gao, Rongjie

    2016-08-01

    Nowadays much effort has been devoted to exploring novel luminescent materials with low-cost, high stability and excellent luminescent properties. In this paper, a new kind of luminescent material BPO4@B2O3 was prepared by using a facile method. The as-obtained samples contain numerous BPO4 nanoparticles enclosed by amorphous and crystalline B2O3 homogeneously, which exhibits a broad emission band ranging from 380 to 700 nm under near-UV irradiation. More importantly, it is worth noting that the BPO4@B2O3 phosphor exhibits the excellent thermal quenching property, which endows it with a promising prospect as phosphors for high power white LEDs. To further promote its application as white light phosphors, Eu3+ ions were doped into the BPO4@B2O3 samples and prepared the (BPO4@B2O3):Eu3+ phosphors with chromaticity coordinates (0.3022, 0.3122). The corresponding packaging of LEDs indicates that both BPO4@B2O3 and (BPO4@B2O3):Eu3+ can be considered as the promising phosphors for WLEDs.

  16. The remarkable optical jet in 4C +00.58

    NASA Astrophysics Data System (ADS)

    Meyer, Eileen T.; Sparks, William B.; Georganopoulos, Markos; Chiaberge, Marco; Perlman, Eric S.

    2017-01-01

    A recent HST program on X-ray detected kpc-scale jets has revealed an infrared/optical jet in the very nearby moderate-power quasar 4C+00.58. At a redshift of only 0.058, it is closer than 3C 273 and also represents a moderate-power analog to that source and the well-studied M87. I will discuss the implications of the multiwavelength data we have on hand, including very recent UV observations with WFC3. In particular, we see evidence of an X-ray excess which may be relevant to the synchrotron/IC origin debate for X-rays in large-scale jets generally.

  17. Dynamical simulation for sputtering of B 4C

    NASA Astrophysics Data System (ADS)

    Kenmotsu, T.; Kawamura, T.; Ono, T.; Yamamura, Y.

    1998-10-01

    Using ACAT-DIFFUSE code, we have simulated the fluence dependence of B 4C sputtering and the associated surface composition change under D + ion bombardment. The ACAT-DIFFUSE is a simulation code, which is based on a Monte Carlo method with a binary collision approximation and solves diffusion equations. In the case of near-threshold sputtering, the preferential sputtering of B atoms is enhanced by the threshold effect. As a result, the total sputtering yield at the steady state is reduced by about 20% compared with low-fluence sputtering. The surface concentration at steady state is determined by the competitive processes between diffusion and surface-atom removal due to sputtering. At normal incidence the interstitial diffusion contributes appreciably to the steady-state surface concentration, but at grazing incidence this effect is small. Therefore, the steady-state surface concentration ratio at grazing incidence is less than that of normal incidence.

  18. Quasar 4C39.25 is not contracting

    NASA Technical Reports Server (NTRS)

    Marcaide, J. M.; Bartel, N.; Gorenstein, M. V.; Shapiro, I. I.; Corey, B. E.; Rogers, A. E. E.; Webber, J. C.; Clark, T. A.; Romney, J. D.; Preston, R. A.

    1985-01-01

    A map has been made of the quasar 4C39.25, which has been described as consisting of two components whose angular separation remains constant at about 2 marc-sec, using VLBI observations made at 3.6 cm during 1983. From the map it is concluded that Shaffer's (1984) suggestion that this source may have been contracting superluminally during 1979-82 is not correct. Three distinct components are found in the quasar structure, two separated by 2.0 marc-sec and a third, presumably new and not previously reported, situated between the other two. It is possible either that the third component is stationary and that its flux density has rapidly increased to render it visible, or that it has recently been ejected from the westernmost component.

  19. Optimization of Al Matrix Reinforced with B4C Particles

    NASA Astrophysics Data System (ADS)

    Shabani, Mohsen Ostad; Mazahery, Ali

    2013-02-01

    In the current study, abrasive wear resistance and mechanical properties of A356 composite reinforced with B4C particulates were investigated. A center particle swarm optimization algorithm (CenterPSO) is proposed to predict the optimal process conditions in fabrication of aluminum matrix composites. Unlike other ordinary particles, the center particle has no explicit velocity and is set to the center of the swarm at every iteration. Other aspects of the center particle are the same as that of the ordinary particle, such as fitness evaluation and competition for the best particle of the swarm. Because the center of the swarm is a promising position, the center particle generally gets good fitness value. More importantly, due to frequent appearance as the best particle of swarm, it often attracts other particles and guides the search direction of the whole swarm.

  20. Peripheral vision horizon display testing in RF-4C aircraft

    NASA Technical Reports Server (NTRS)

    Hammond, L. B., Jr.

    1984-01-01

    A test program to assess the capability of the peripheral vision horizon display (PVHD) to provide peripheral attitude cues to the pilot is described. The system was installed in the rear cockpit of a RF-4C aircraft, selected because its poor instrument crosscheck conditions. The PVHD test plan was designed to assess three primary areas: (1) ability of the system to reduce spatial disorientation; (2) ability of the system to aid the pilot in recovering from unusual attitudes; and (3) improvement in pilot performance during instrument landing system (ILS) approaches. Results of preliminary test flights are summarized. The major problem areas concern the distinction of the display itself and the capability of the display to provide pitch motion cues.

  1. LAPTM4B: an oncogene in various solid tumors and its functions

    PubMed Central

    Meng, Y; Wang, L; Chen, D; Chang, Y; Zhang, M; XU, J-J; Zhou, R; Zhang, Q-Y

    2016-01-01

    The oncogene Lysosome-associated protein transmembrane-4β (LAPTM4B) gene was identified, and the polymorphism region in the 5′-UTR of this gene was certified to be associated with tumor susceptibility. LAPTM4B-35 protein was found to be highly expressed in various solid tumors and could be a poor prognosis marker. The functions of LAPTM4B in solid tumors were also explored. It is suggested that LAPTM4B could promote the proliferation of tumor cells, boost invasion and metastasis, resist apoptosis, initiate autophagy and assist drug resistance. PMID:27212036

  2. The transcription activity of heat shock factor 4b is regulated by FGF2.

    PubMed

    Hu, Yan-Zhong; Zhang, Jun; Li, Shulian; Wang, Chuan; Chu, Liujie; Zhang, Zhi; Ma, Zengyi; Wang, Mingli; Jiang, Qiying; Liu, Guangchao; Qi, Yijun; Ma, Yuanfang

    2013-02-01

    Heat shock factor 4b has been found to be closely associated with postnatal lens development. It expresses in postnatal lens epithelial and secondary fiber cells and controls the expression of small heat shock proteins which are important for lens homeostasis. However, the signal pathways underlying Hsf4b are still not completely understood. Here we present that Hsf4b transcription activity is regulated by FGF2 a key growth factor that is involved in regulating lens development at multiple stages. FGF2 can promote Hsf4b nuclear-translocation and the expression of Hsp25 and αB-crystallin, the key downstream targets of Hsf4b in the Hsf4b-reconstituted mouse hsf4-/- lens epithelial cells. Further study indicates that FGF2 can induce Hsf4b protein stabilization through ERK1/2-mediated posttranslational phosphorylation or sumoylation. Hsf4b can promote FGF2-induced morphology transition from lens epithelial cell to the fiber cell, and this morphology transition can be inhibited by ERK1/2 inhibitor U0126. Taken together, our data demonstrate that Hsf4b is a novel downstream transcription factor of FGF2, and its transcription activity is associated with FGF2-modulated lens epithelial cell-fiber cell transition.

  3. Mapping the Interactions between the NS4B and NS3 Proteins of Dengue Virus

    PubMed Central

    Zou, Jing; Lee, Le Tian; Wang, Qing Yin; Xie, Xuping; Lu, Siyan; Yau, Yin Hoe; Yuan, Zhiming; Geifman Shochat, Susana; Kang, Congbao

    2015-01-01

    ABSTRACT Flavivirus RNA synthesis is mediated by a multiprotein complex associated with the endoplasmic reticulum membrane, named the replication complex (RC). Within the flavivirus RC, NS4B, an integral membrane protein with a role in virulence and regulation of the innate immune response, binds to the NS3 protease-helicase. NS4B modulates the RNA helicase activity of NS3, but the molecular details of their interaction remain elusive. Here, we used dengue virus (DENV) to map the determinants for the NS3-NS4B interaction. Coimmunoprecipitation and an in situ proximity ligation assay confirmed that NS3 colocalizes with NS4B in both DENV-infected cells and cells coexpressing both proteins. Surface plasmon resonance demonstrated that subdomains 2 and 3 of the NS3 helicase region and the cytoplasmic loop of NS4B are required for binding. Using nuclear magnetic resonance (NMR), we found that the isolated cytoplasmic loop of NS4B is flexible, with a tendency to form a three-turn α-helix and two short β-strands. Upon binding to the NS3 helicase, 12 amino acids within the cytoplasmic loop of NS4B exhibited line broadening, suggesting a participation in the interaction. Sequence alignment showed that 4 of these 12 residues are strictly conserved across different flaviviruses. Mutagenesis analysis showed that three (Q134, G140, and N144) of the four evolutionarily conserved NS4B residues are essential for DENV replication. The mapping of the NS3/NS4B-interacting regions described here can assist the design of inhibitors that disrupt their interface for antiviral therapy. IMPORTANCE NS3 and NS4B are essential components of the flavivirus RC. Using DENV as a model, we mapped the interaction between the viral NS3 and NS4B proteins. The subdomains 2 and 3 of NS3 helicase as well as the cytoplasmic loop of NS4B are critical for the interaction. Functional analysis delineated residues within the NS4B cytoplasmic loop that are crucial for DENV replication. Our findings reveal

  4. Mutations in classical swine fever virus NS4B affect virulence in swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NS4B is one of the non-structural proteins of Classical Swine Fever Virus (CSFV), a virus causing a severe disease in swine. Protein domain analysis of the predicted amino acid sequence of NS4B in highly pathogenic CSFV strain Brescia (BICv) identified a Toll/Interleukin-1 receptor like domain (TIR...

  5. Mutations in the classical swine fever virus NS4B protein affects virulence in swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NS4B is one of the non-structural proteins of Classical Swine Fever Virus (CSFV), the etiological agent of a severe, highly lethal disease of swine. Protein domain analysis of the predicted amino acid sequence of the NS4B protein of highly pathogenic CSFV strain Brescia (BICv) identified a Toll/Inte...

  6. 78 FR 63221 - International Conference on Harmonisation; Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-23

    ... Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... availability of a guidance entitled ``Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the... ICH Q4B evaluation of the Bacterial Endotoxins Test General Chapter harmonized text from each of...

  7. 76 FR 37129 - International Conference on Harmonisation; Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... ] availability of a guidance entitled ``Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the... published ICH guidance, ``Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the...

  8. Atypical Listeria monocytogenes Serotype 4b strains harboring a lineage II-specific gene cassette

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Listeria monocytogenes is the etiological agent of listeriosis, a severe foodborne illness. The population of L. monocytogenes is divided into four lineages (I-IV) and serotype 4b in lineage I has been involved in numerous outbreaks. Several serotype 4b epidemic-associated clonal groups (ECI, II, an...

  9. TAF4b Regulates Oocyte-Specific Genes Essential for Meiosis

    PubMed Central

    Grive, Kathryn J.; Gustafson, Eric A.; Seymour, Kimberly A.; Baddoo, Melody; Schorl, Christoph; Golnoski, Kayla; Rajkovic, Aleksandar; Brodsky, Alexander S.; Freiman, Richard N.

    2016-01-01

    TAF4b is a gonadal-enriched subunit of the general transcription factor TFIID that is implicated in promoting healthy ovarian aging and female fertility in mice and humans. To further explore the potential mechanism of TAF4b in promoting ovarian follicle development, we analyzed global gene expression at multiple time points in the human fetal ovary. This computational analysis revealed coordinate expression of human TAF4B and critical regulators and effectors of meiosis I including SYCP3, YBX2, STAG3, and DAZL. To address the functional relevance of this analysis, we turned to the embryonic Taf4b-deficient mouse ovary where, for the first time, we demonstrate, severe deficits in prophase I progression as well as asynapsis in Taf4b-deficient oocytes. Accordingly, TAF4b occupies the proximal promoters of many essential meiosis and oogenesis regulators, including Stra8, Dazl, Figla, and Nobox, and is required for their proper expression. These data reveal a novel TAF4b function in regulating a meiotic gene expression program in early mouse oogenesis, and support the existence of a highly conserved TAF4b-dependent gene regulatory network promoting early oocyte development in both mice and women. PMID:27341508

  10. FourCSeq: analysis of 4C sequencing data

    PubMed Central

    Klein, Felix A.; Pakozdi, Tibor; Anders, Simon; Ghavi-Helm, Yad; Furlong, Eileen E. M.; Huber, Wolfgang

    2015-01-01

    Motivation: Circularized Chromosome Conformation Capture (4C) is a powerful technique for studying the spatial interactions of a specific genomic region called the ‘viewpoint’ with the rest of the genome, both in a single condition or comparing different experimental conditions or cell types. Observed ligation frequencies typically show a strong, regular dependence on genomic distance from the viewpoint, on top of which specific interaction peaks are superimposed. Here, we address the computational task to find these specific peaks and to detect changes between different biological conditions. Results: We model the overall trend of decreasing interaction frequency with genomic distance by fitting a smooth monotonically decreasing function to suitably transformed count data. Based on the fit, z-scores are calculated from the residuals, and high z-scores are interpreted as peaks providing evidence for specific interactions. To compare different conditions, we normalize fragment counts between samples, and call for differential contact frequencies using the statistical method DESeq2 adapted from RNA-Seq analysis. Availability and implementation: A full end-to-end analysis pipeline is implemented in the R package FourCSeq available at www.bioconductor.org. Contact: felix.klein@embl.de or whuber@embl.de Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26034064

  11. Metabolism of [(1)(4)C]prometryn in rats.

    PubMed

    Maynard, M S; Brumback, D; Itterly, W; Capps, T; Rose, R

    1999-09-01

    [(1)(4)C]Prometryn, 2, 4-bis(isopropylamino)-6-(methylthio)-s-triazine, was orally administered to male and female rats at approximately 0.5 and 500 mg/kg; daily urine and feces were collected. After 3 or 7 days rats were sacrificed, and blood and selected tissues were isolated. The urine and feces extracts were characterized for metabolite similarity as well as for metabolite identification. Over 30 metabolites were observed, and of these, 28 were identified mostly by mass spectrometry and/or cochromatography with available reference standards. The metabolism of prometryn was shown to occur by N-demethylation, S-oxidation, S-S dimerization, OH substitution for NH(2) and SCH(3), and conjugation with glutathione or glucuronic acid. Rat liver microsomal incubations of prometryn were conducted and compared to the in vivo metabolism. Both in vivo and in vitro phase I metabolisms of prometryn were similar, with S-oxidation and N-dealkylation predominating. The involvement of cytochrome P-450 and flavin-containing monooxidase in the in vitro metabolism of prometryn was investigated.

  12. Identification of breast cancer cell subtypes sensitive to ATG4B inhibition

    PubMed Central

    Bortnik, Svetlana; Choutka, Courtney; Horlings, Hugo M.; Leung, Samuel; Baker, Jennifer H.; Lebovitz, Chandra; Dragowska, Wieslawa H.; Go, Nancy E.; Bally, Marcel B.; Minchinton, Andrew I.; Gelmon, Karen A.; Gorski, Sharon M.

    2016-01-01

    Autophagy, a lysosome-mediated degradation and recycling process, functions in advanced malignancies to promote cancer cell survival and contribute to cancer progression and drug resistance. While various autophagy inhibition strategies are under investigation for cancer treatment, corresponding patient selection criteria for these autophagy inhibitors need to be developed. Due to its central roles in the autophagy process, the cysteine protease ATG4B is one of the autophagy proteins being pursued as a potential therapeutic target. In this study, we investigated the expression of ATG4B in breast cancer, a heterogeneous disease comprised of several molecular subtypes. We examined a panel of breast cancer cell lines, xenograft tumors, and breast cancer patient specimens for the protein expression of ATG4B, and found a positive association between HER2 and ATG4B protein expression. We showed that HER2-positive cells, but not HER2-negative breast cancer cells, require ATG4B to survive under stress. In HER2-positive cells, cytoprotective autophagy was dependent on ATG4B under both starvation and HER2 inhibition conditions. Combined knockdown of ATG4B and HER2 by siRNA resulted in a significant decrease in cell viability, and the combination of ATG4B knockdown with trastuzumab resulted in a greater reduction in cell viability compared to trastuzumab treatment alone, in both trastuzumab-sensitive and -resistant HER2 overexpressing breast cancer cells. Together these results demonstrate a novel association of ATG4B positive expression with HER2 positive breast cancers and indicate that this subtype is suitable for emerging ATG4B inhibition strategies. PMID:27556700

  13. (4bS,8aS)-1-Isopropyl-4b,8,8-trimethyl-4b,5,6,7,8,8a,9,10-octa­hydro­phenan­thren-2-yl acetate

    PubMed Central

    Oubabi, Radouane; Auhmani, Aziz; Ait Itto, My Youssef; Auhmani, Abdelwahed; Daran, Jean-Claude

    2014-01-01

    The hemisynthesis of the title compound, C22H32O2, was carried out through direct acetyl­ation reaction of the naturally occurring diterpene totarol [systematic name: (4bS,8aS)-4b,8,8-trimethyl-1-propan-2-yl-5,6,7,8a,9,10-hexa­hydro­phen­an­thren-2-ol]. The mol­ecule is built up from three fused six membered rings, one saturated and two unsaturated. The central unsaturated ring has a half-chair conformation, whereas the other unsaturated ring displays a chair conformation. The absolute configuration is deduced from the chemical pathway. The value of the Hooft parameter [−0.10 (6)] allowed this absolute configuration to be confirmed. PMID:24765017

  14. INPP4B is an oncogenic regulator in human colon cancer

    PubMed Central

    Guo, S T; Chi, M N; Yang, R H; Guo, X Y; Zan, L K; Wang, C Y; Xi, Y F; Jin, L; Croft, A; Tseng, H-Y; Yan, X G; Farrelly, M; Wang, F H; Lai, F; Wang, J F; Li, Y P; Ackland, S; Scott, R; Agoulnik, I U; Hondermarck, H; Thorne, R F; Liu, T; Zhang, X D; Jiang, C C

    2016-01-01

    Inositol polyphosphate 4-phosphatase type II (INPP4B) negatively regulates phosphatidylinositol 3-kinase signaling and is a tumor suppressor in some types of cancers. However, we have found that it is frequently upregulated in human colon cancer cells. Here we show that silencing of INPP4B blocks activation of Akt and serum- and glucocorticoid-regulated kinase 3 (SGK3), inhibits colon cancer cell proliferation and retards colon cancer xenograft growth. Conversely, overexpression of INPP4B increases proliferation and triggers anchorage-independent growth of normal colon epithelial cells. Moreover, we demonstrate that the effect of INPP4B on Akt and SGK3 is associated with inactivation of phosphate and tensin homolog through its protein phosphatase activity and that the increase in INPP4B is due to Ets-1-mediated transcriptional upregulation in colon cancer cells. Collectively, these results suggest that INPP4B may function as an oncogenic driver in colon cancer, with potential implications for targeting INPP4B as a novel approach to treat this disease. PMID:26411369

  15. Mitotic MELK-eIF4B signaling controls protein synthesis and tumor cell survival

    PubMed Central

    Wang, Yubao; Begley, Michael; Li, Qing; Huang, Hai-Tsang; Lako, Ana; Eck, Michael J.; Gray, Nathanael S.; Mitchison, Timothy J.; Cantley, Lewis C.; Zhao, Jean J.

    2016-01-01

    The protein kinase maternal and embryonic leucine zipper kinase (MELK) is critical for mitotic progression of cancer cells; however, its mechanisms of action remain largely unknown. By combined approaches of immunoprecipitation/mass spectrometry and peptide library profiling, we identified the eukaryotic translation initiation factor 4B (eIF4B) as a MELK-interacting protein during mitosis and a bona fide substrate of MELK. MELK phosphorylates eIF4B at Ser406, a modification found to be most robust in the mitotic phase of the cell cycle. We further show that the MELK–eIF4B signaling axis regulates protein synthesis during mitosis. Specifically, synthesis of myeloid cell leukemia 1 (MCL1), an antiapoptotic protein known to play a role in cancer cell survival during cell division, depends on the function of MELK-elF4B. Inactivation of MELK or eIF4B results in reduced protein synthesis of MCL1, which, in turn, induces apoptotic cell death of cancer cells. Our study thus defines a MELK–eIF4B signaling axis that regulates protein synthesis during mitosis, and consequently influences cancer cell survival. PMID:27528663

  16. ATG4B/autophagin-1 regulates intestinal homeostasis and protects mice from experimental colitis

    PubMed Central

    Cabrera, Sandra; Fernández, Álvaro F.; Mariño, Guillermo; Aguirre, Alina; Suárez, María F.; Español, Yaiza; Vega, José A.; Laurà, Rosaria; Fueyo, Antonio; Fernández-García, M. Soledad; Freije, José M.P.; Kroemer, Guido; López-Otín, Carlos

    2013-01-01

    The identification of inflammatory bowel disease (IBD) susceptibility genes by genome-wide association has linked this pathology to autophagy, a lysosomal degradation pathway that is crucial for cell and tissue homeostasis. Here, we describe autophagy-related 4B, cysteine peptidase/autophagin-1 (ATG4B) as an essential protein in the control of inflammatory response during experimental colitis. In this pathological condition, ATG4B protein levels increase in parallel with the induction of autophagy. Moreover, ATG4B expression is significantly reduced in affected areas of the colon from IBD patients. Consistently, atg4b−/− mice present Paneth cell abnormalities, as well as an increased susceptibility to DSS-induced colitis. atg4b-deficient mice exhibit significant alterations in proinflammatory cytokines and mediators of the immune response to bacterial infections, which are reminiscent of those found in patients with Crohn disease or ulcerative colitis. Additionally, antibiotic treatments and bone marrow transplantation from wild-type mice reduced colitis in atg4b−/− mice. Taken together, these results provided additional evidence for the importance of autophagy in intestinal pathologies and describe ATG4B as a novel protective protein in inflammatory colitis. Finally, we propose that atg4b-null mice are a suitable model for in vivo studies aimed at testing new therapeutic strategies for intestinal diseases associated with autophagy deficiency. PMID:23782979

  17. Heat capacity, resistivity, and angular dependent magnetization studies of single crystal Nd1+ϵFe4B4 for ϵ≈17

    DOE PAGES

    Conner, Benjamin S.; Susner, Michael A.; Lampen-Kelley, Paula; ...

    2017-04-04

    Advances in crystal growth have allowed for synthesis of large single crystals of Nd1+ϵFe4B4, a well-known phase with a modulated structure. As a result we are able to report heat capacity and resistivity measurements on a single crystal Nd1+ϵFe4B4 sample with a distribution of ϵ that skews towards the solubility limit of Nd near ϵ ≈ 17. Heat capacity measurements show evidence of crystal field splitting at temperatures higher than the long-range ferromagnetic Curie temperature. Heat capacity, resistivity, and magnetization measurements all confirm a Curie temperature of 7 K which is lower than previously reported values in the Nd1+ϵFe4B4 system.more » Here, we also perform measurements of the angular dependence of the magnetization and discover behavior associated with the magnetic anisotropy that is inconsistent with the simple description previously proposed.« less

  18. A C-terminal di-leucine motif controls plasma membrane expression of PMCA4b.

    PubMed

    Antalffy, Géza; Pászty, Katalin; Varga, Karolina; Hegedűs, Luca; Enyedi, Agnes; Padányi, Rita

    2013-12-01

    Recent evidences show that the localization of different plasma membrane Ca(2+) ATPases (PMCAs) is regulated in various complex, cell type-specific ways. Here we show that in low-density epithelial and endothelial cells PMCA4b localized mostly in intracellular compartments and its plasma membrane localization was enhanced upon increasing density of cells. In good correlation with the enhanced plasma membrane localization a significantly more efficient Ca(2+) clearance was observed in confluent versus non-confluent HeLa cell cultures expressing mCherry-PMCA4b. We analyzed the subcellular localization and function of various C-terminally truncated PMCA4b variants and found that a truncated mutant PMCA4b-ct24 was mostly intracellular while another mutant, PMCA4b-ct48, localized more to the plasma membrane, indicating that a protein sequence corresponding to amino acid residues 1158-1181 contained a signal responsible for the intracellular retention of PMCA4b in non-confluent cultures. Alteration of three leucines to alanines at positions 1167-1169 resulted in enhanced cell surface expression and an appropriate Ca(2+) transport activity of both wild type and truncated pumps, suggesting that the di-leucine-like motif (1167)LLL was crucial in targeting PMCA4b. Furthermore, upon loss of cell-cell contact by extracellular Ca(2+) removal, the wild-type pump was translocated to the early endosomal compartment. Targeting PMCA4b to early endosomes was diminished by the L(1167-69)A mutation, and the mutant pump accumulated in long tubular cytosolic structures. In summary, we report a di-leucine-like internalization signal at the C-tail of PMCA4b and suggest an internalization-mediated loss of function of the pump upon low degree of cell-cell contact.

  19. LAPTM4B Gene Expression and Polymorphism as Diagnostic Markers of Breast Cancer in Egyptian Patients

    PubMed Central

    Shaker, Olfat; Taha, Fatma; Salah, Maha; El-Marzouky, Mohamed

    2015-01-01

    Summary Background The aim of this study was to investigate the association between LAPTM4B gene polymorphism and the risk of breast cancer among Egyptian female patients. Also, measurement was done of its serum level to evaluate its significance as a diagnostic marker for breast cancer. Methods This case control study was done on 88 breast cancer patients, 40 with fibroadenoma and 80 healthy subjects. Genotyping of the LAPTM4B polymorphism was determined by PCR. Serum LAPTM4B level was measured using ELISA. Results There was a significant difference in the (*1/2+ *2/2) genotypes in breast cancer patients (59.1) compared to the control subjects (43.8%) (P=0.047; OR=1.86; 95% CI =1.01–3.43). The frequency of the allele 2* of the LAPTM4B gene was significantly higher in breast cancer patients (36.4%) than in the control (25.6%) (p=0.034; OR=1.66; 95% CI =1.04–2.65). Genotypes (*1/2+*2/2) were significantly associated with the differential classification of TNM. Serum level of LAPTM4B was significantly higher in breast cancer patients than in control and fibroadenoma and in fibroadenoma patients than in control. In breast cancer patients, serum LAPTM4B was significantly higher in stage III and in large tumor size. Serum LAPTM4B was significantly higher in the cancer patients’ genotypes (*1/2+*2/2). Conclusions Genetic polymorphism of LAPTM4B is a potential risk factor for the development of breast cancer. Serum LAPTM4B may be used as a diagnostic and prognostic marker for breast cancer. PMID:28356847

  20. Chronic Cognitive Dysfunction after Traumatic Brain Injury Is Improved with a Phosphodiesterase 4B Inhibitor

    PubMed Central

    Titus, David J.; Wilson, Nicole M.; Freund, Julie E.; Carballosa, Melissa M.; Sikah, Kevin E.; Furones, Concepcion; Dietrich, W. Dalton; Gurney, Mark E.

    2016-01-01

    Learning and memory impairments are common in traumatic brain injury (TBI) survivors. However, there are no effective treatments to improve TBI-induced learning and memory impairments. TBI results in decreased cAMP signaling and reduced cAMP-response-element binding protein (CREB) activation, a critical pathway involved in learning and memory. TBI also acutely upregulates phosphodiesterase 4B2 (PDE4B2), which terminates cAMP signaling by hydrolyzing cAMP. We hypothesized that a subtype-selective PDE4B inhibitor could reverse the learning deficits induced by TBI. To test this hypothesis, adult male Sprague-Dawley rats received sham surgery or moderate parasagittal fluid-percussion brain injury. At 3 months postsurgery, animals were administered a selective PDE4B inhibitor or vehicle before cue and contextual fear conditioning, water maze training and a spatial working memory task. Treatment with the PDE4B inhibitor significantly reversed the TBI-induced deficits in cue and contextual fear conditioning and water maze retention. To further understand the underlying mechanisms of these memory impairments, we examined hippocampal long-term potentiation (LTP). TBI resulted in a significant reduction in basal synaptic transmission and impaired expression of LTP. Treatment with the PDE4B inhibitor significantly reduced the deficits in basal synaptic transmission and rescued LTP expression. The PDE4B inhibitor reduced tumor necrosis factor-α levels and increased phosphorylated CREB levels after TBI, suggesting that this drug inhibited molecular pathways in the brain known to be regulated by PDE4B. These results suggest that a subtype-selective PDE4B inhibitor is a potential therapeutic to reverse chronic learning and memory dysfunction and deficits in hippocampal synaptic plasticity following TBI. SIGNIFICANCE STATEMENT Currently, there are an estimated 3.2–5.3 million individuals living with disabilities from traumatic brain injury (TBI) in the United States, and 8 of

  1. Two New Copper Borates with Mesoscale Cubic Supramolecular Cages Assembled from {Cu4 @B20 } Clusters.

    PubMed

    Wang, Jia-Jia; Wei, Qi; Yang, Bai-Feng; Yang, Guo-Yu

    2017-02-24

    Two new copper borates, namely H6 [(μ4 -O)Cu4 @B20 O32 (OH)8 ]⋅25 H2 O (1) and H6 [(μ4 -O)Cu4 @B20 O32 (OH)8 ]⋅34 H2 O⋅8 H3 BO3 (2), with 3D supramolecular framework have been made under solvothermal conditions, which built by novel cubic supramolecular cages with mesoscale cavities via the H-bondings. Interestingly, the cage is assembled by [(μ4 -O)Cu4 @B20 O32 (OH)8 ] ({Cu4 @B20 }) cluster units with different point-group symmetry. Owing to extra H3 BO3 molecules participated in building the supramolecular framework, 2 has a larger cubic cage size and higher non-framework volume, leading to the cage size extended to mesoporous size set as a version of ''1 plus".

  2. VizieR Online Data Catalog: XO-4b 3yr observations with DEMONEX (Villanueva+, 2016)

    NASA Astrophysics Data System (ADS)

    Villanueva, S. Jr; Eastman, J. D.; Gaudi, B. S.

    2016-06-01

    New observations of XO-4b were made using DEdicated MONitor of EXotransits (DEMONEX). DEMONEX monitored bright stars hosting known transiting planets over a 3yr period from 2008 to 2011 in order to provide a homogeneous data set of precise relative photometry for over 40 transiting systems. There are 20 nights of data from 2008 November to 2010 May taken during primary transits of XO-4b. All observations were made in the Sloan z band. (1 data file).

  3. Current Drug Discovery for Anti-hepatitis C Virus Targeting NS4B.

    PubMed

    Wang, Zhenya; Chen, Xinli; Wu, Chunli; Xu, Haiwei; Liu, Hongmin

    2016-01-01

    Hepatitis C virus (HCV) infection is a major worldwide epidemic disease. It is estimated that more than 170 million individuals are infected with HCV and with three to four million new cases each year. Many new direct-acting antiviral (DAA) agents that specifically target HCV NS3 protease or NS5B polymerase inhibitors are therefore in development, with a significant effect for the patient and for the market recently. The non-structural 4B (NS4B) protein, is among the least characterized of the HCV proteins. A variety of functions have been recognized for NS4B, such as the ability to induce the membranous web replication platform, RNA binding and NTPase activity. In order to maximize antiviral efficacy and prevent the emergence of resistance, novel NS4B inhibitors have been subjected to pharmacological studies. In this review, we discussed current understanding of the structure and function of NS4B, and novel drug discoveries targeting NS4B as anti-hepatitis C virus such as sulfonamide, piperidine, carboxamide, piperazinone and quinoline derivatives within the last three years.

  4. UBE4B targets phosphorylated p53 at serines 15 and 392 for degradation

    PubMed Central

    Du, Cheng; Wu, Hong; Leng, Roger P.

    2016-01-01

    Phosphorylation of p53 is a key mechanism responsible for the activation of its tumor suppressor functions in response to various stresses. In unstressed cells, p53 is rapidly turned over and is maintained at a low basal level. After DNA damage or other forms of cellular stress, the p53 level increases, and the protein becomes metabolically stable. However, the mechanism of phosphorylated p53 regulation is unclear. In this study, we studied the kinetics of UBE4B, Hdm2, Pirh2, Cop1 and CHIP induction in response to p53 activation. We show that UBE4B coimmunoprecipitates with phosphorylated p53 at serines 15 and 392. Notably, the affinity between UBE4B and Hdm2 is greatly decreased after DNA damage. Furthermore, we observe that UBE4B promotes endogenous phospho-p53(S15) and phospho-p53(S392) degradation in response to IR. We demonstrate that UBE4B and Hdm2 repress p53S15A, p53S392A, and p53-2A(S15A, S392A) functions, including p53-dependent transactivation and growth inhibition. Overall, our results reveal that UBE4B plays an important role in regulating phosphorylated p53 following DNA damage. PMID:26673821

  5. O-GlcNAcylation of ATG4B positively regulates autophagy by increasing its hydroxylase activity.

    PubMed

    Jo, Yoon Kyung; Park, Na Yeon; Park, So Jung; Kim, Byung-Gyu; Shin, Ji Hyun; Jo, Doo Sin; Bae, Dong-Jun; Suh, Young-Ah; Chang, Jeong Ho; Lee, Eun Kyung; Kim, Sang-Yeob; Kim, Jin Cheon; Cho, Dong-Hyung

    2016-08-30

    Autophagy is a catabolic degradation process and maintains cellular homeostasis. And autophagy is activated in response to various stress conditions. Although O-GlcNAcylation functions a sensor for nutrient and stress, the relationship between O-GlcNAcylation and autophagy is largely unknown. Here, we identified that ATG4B is novel target for O-GlcNAcylation under metabolic stress condition. Treatment with PugNAc, an O-GlcNAcase inhibitor increased activation of autophagy in SH-SY5Y cells. Both bimolecular fluorescence complementation and immunoprecipitation assay indicated that OGT directly interacts with ATG4B in SH-SY5Y cells. We also found that the O-GlcNAcylated ATG4B was increased in autophagy activation conditions, and down-regulation of OGT reduces O-GlcNAcylation of ATG4B under low glucose condition. Furthermore, the proteolytic activity of ATG4B for LC3 cleavage was enhanced in PugNAc-treated cells. Taken together, these results imply that O-GlcNAcylation of ATG4B regulates autophagy activation by increasing its proteolytic activity under metabolic stress condition.

  6. O-GlcNAcylation of ATG4B positively regulates autophagy by increasing its hydroxylase activity

    PubMed Central

    Jo, Yoon Kyung; Park, Na Yeon; Park, So Jung; Kim, Byung-Gyu; Shin, Ji Hyun; Jo, Doo Sin; Bae, Dong-Jun; Suh, Young-Ah; Chang, Jeong Ho; Lee, Eun Kyung; Kim, Sang-Yeob; Kim, Jin Cheon; Cho, Dong-Hyung

    2016-01-01

    Autophagy is a catabolic degradation process and maintains cellular homeostasis. And autophagy is activated in response to various stress conditions. Although O-GlcNAcylation functions a sensor for nutrient and stress, the relationship between O-GlcNAcylation and autophagy is largely unknown. Here, we identified that ATG4B is novel target for O-GlcNAcylation under metabolic stress condition. Treatment with PugNAc, an O-GlcNAcase inhibitor increased activation of autophagy in SH-SY5Y cells. Both bimolecular fluorescence complementation and immunoprecipitation assay indicated that OGT directly interacts with ATG4B in SH-SY5Y cells. We also found that the O-GlcNAcylated ATG4B was increased in autophagy activation conditions, and down-regulation of OGT reduces O-GlcNAcylation of ATG4B under low glucose condition. Furthermore, the proteolytic activity of ATG4B for LC3 cleavage was enhanced in PugNAc-treated cells. Taken together, these results imply that O-GlcNAcylation of ATG4B regulates autophagy activation by increasing its proteolytic activity under metabolic stress condition. PMID:27527864

  7. Mechanisms of Membrane Binding of Small GTPase K-Ras4B Farnesylated Hypervariable Region*

    PubMed Central

    Jang, Hyunbum; Abraham, Sherwin J.; Chavan, Tanmay S.; Hitchinson, Ben; Khavrutskii, Lyuba; Tarasova, Nadya I.; Nussinov, Ruth; Gaponenko, Vadim

    2015-01-01

    K-Ras4B belongs to a family of small GTPases that regulates cell growth, differentiation and survival. K-ras is frequently mutated in cancer. K-Ras4B association with the plasma membrane through its farnesylated and positively charged C-terminal hypervariable region (HVR) is critical to its oncogenic function. However, the structural mechanisms of membrane association are not fully understood. Here, using confocal microscopy, surface plasmon resonance, and molecular dynamics simulations, we observed that K-Ras4B can be distributed in rigid and loosely packed membrane domains. Its membrane binding domain interaction with phospholipids is driven by membrane fluidity. The farnesyl group spontaneously inserts into the disordered lipid microdomains, whereas the rigid microdomains restrict the farnesyl group penetration. We speculate that the resulting farnesyl protrusion toward the cell interior allows oligomerization of the K-Ras4B membrane binding domain in rigid microdomains. Unlike other Ras isoforms, K-Ras4B HVR contains a single farnesyl modification and positively charged polylysine sequence. The high positive charge not only modulates specific HVR binding to anionic phospholipids but farnesyl membrane orientation. Phosphorylation of Ser-181 prohibits spontaneous farnesyl membrane insertion. The mechanism illuminates the roles of HVR modifications in K-Ras4B targeting microdomains of the plasma membrane and suggests an additional function for HVR in regulation of Ras signaling. PMID:25713064

  8. KDM4B is a master regulator of the estrogen receptor signalling cascade.

    PubMed

    Gaughan, Luke; Stockley, Jacqueline; Coffey, Kelly; O'Neill, Daniel; Jones, Dominic L; Wade, Mark; Wright, Jamie; Moore, Madeleine; Tse, Sandy; Rogerson, Lynsey; Robson, Craig N

    2013-08-01

    The importance of the estrogen receptor (ER) in breast cancer (BCa) development makes it a prominent target for therapy. Current treatments, however, have limited effectiveness, and hence the definition of new therapeutic targets is vital. The ER is a member of the nuclear hormone receptor superfamily of transcription factors that requires co-regulator proteins for complete regulation. Emerging evidence has implicated a small number of histone methyltransferase (HMT) and histone demethylase (HDM) enzymes as regulators of ER signalling, including the histone H3 lysine 9 tri-/di-methyl HDM enzyme KDM4B. Two recent independent reports have demonstrated that KDM4B is required for ER-mediated transcription and depletion of the enzyme attenuates BCa growth in vitro and in vivo. Here we show that KDM4B has an overarching regulatory role in the ER signalling cascade by controlling expression of the ER and FOXA1 genes, two critical components for maintenance of the estrogen-dependent phenotype. KDM4B interacts with the transcription factor GATA-3 in BCa cell lines and directly co-activates GATA-3 activity in reporter-based experiments. Moreover, we reveal that KDM4B recruitment and demethylation of repressive H3K9me3 marks within upstream regulatory regions of the ER gene permits binding of GATA-3 to drive receptor expression. Ultimately, our findings confirm the importance of KDM4B within the ER signalling cascade and as a potential therapeutic target for BCa treatment.

  9. F-4C/D Life Extension Program.

    DTIC Science & Technology

    1982-10-01

    Engineering Laboratory (SEL) Systems 86 digital computer for raw data collection, magnetic tape storage , and on-line data processing for test...calibration/standardization output for all channels. Several random strain gage, load cell, and deflection channels, 41 AFWAL-TR-82-3047 0 0 ui c Ic , 0r 0002...1S’ 31 AFT PINE’! SE�T ON It T r .1 EM.~ t m- v"A. " ICE OF ’ �,140 COOKS -qfGF ON eWft NG’ ’!tI 14 I NKAt 5f 2-32-1-431 4A6 ERAMtN A1 . 4--.K

  10. Neuroblastoma patient outcomes, tumor differentiation, and ERK activation are correlated with expression levels of the ubiquitin ligase UBE4B

    PubMed Central

    Woodfield, Sarah E.; Guo, Rong Jun; Liu, Yin; Major, Angela M.; Hollingsworth, Emporia Faith; Indiviglio, Sandra; Whittle, Sarah B.; Mo, Qianxing; Bean, Andrew J.; Ittmann, Michael; Lopez-Terrada, Dolores; Zage, Peter E.

    2016-01-01

    Background UBE4B is an E3/E4 ubiquitin ligase whose gene is located in chromosome 1p36.22. We analyzed the associations of UBE4B gene and protein expression with neuroblastoma patient outcomes and with tumor prognostic features and histology. Methods We evaluated the association of UBE4B gene expression with neuroblastoma patient outcomes using the R2 Platform. We screened neuroblastoma tumor samples for UBE4B protein expression using immunohistochemistry. FISH for UBE4B and 1p36 deletion was performed on tumor samples. We then evaluated UBE4B expression for associations with prognostic factors and with levels of phosphorylated ERK in neuroblastoma tumors and cell lines. Results Low UBE4B gene expression is associated with poor outcomes in patients with neuroblastoma and with worse outcomes in all patient subgroups. UBE4B protein expression was associated with neuroblastoma tumor differentiation, and decreased UBE4B protein levels were associated with high-risk features. UBE4B protein levels were also associated with levels of phosphorylated ERK. Conclusions We have demonstrated associations between UBE4B gene expression and neuroblastoma patient outcomes and prognostic features. Reduced UBE4B protein expression in neuroblastoma tumors was associated with high-risk features, a lack of differentiation, and with ERK activation. These results suggest UBE4B may contribute to the poor prognosis of neuroblastoma tumors with 1p36 deletions and that UBE4B expression may mediate neuroblastoma differentiation. PMID:27014418

  11. eIF4B stimulates translation of long mRNAs with structured 5′ UTRs and low closed-loop potential but weak dependence on eIF4G

    PubMed Central

    Sen, Neelam Dabas; Zhou, Fujun; Harris, Michael S.; Ingolia, Nicholas T.

    2016-01-01

    DEAD-box RNA helicases eukaryotic translation initiation factor 4A (eIF4A) and Ded1 promote translation by resolving mRNA secondary structures that impede preinitiation complex (PIC) attachment to mRNA or scanning. Eukaryotic translation initiation factor 4B (eIF4B) is a cofactor for eIF4A but also might function independently of eIF4A. Ribosome profiling of mutants lacking eIF4B or with impaired eIF4A or Ded1 activity revealed that eliminating eIF4B reduces the relative translational efficiencies of many more genes than does inactivation of eIF4A, despite comparable reductions in bulk translation, and few genes display unusually strong requirements for both factors. However, either eliminating eIF4B or inactivating eIF4A preferentially impacts mRNAs with longer, more structured 5′ untranslated regions (UTRs). These findings reveal an eIF4A-independent role for eIF4B in addition to its function as eIF4A cofactor in promoting PIC attachment or scanning on structured mRNAs. eIF4B, eIF4A, and Ded1 mutations also preferentially impair translation of longer mRNAs in a fashion mitigated by the ability to form closed-loop messenger ribonucleoprotein particles (mRNPs) via eIF4F–poly(A)-binding protein 1 (Pab1) association, suggesting cooperation between closed-loop assembly and eIF4B/helicase functions. Remarkably, depleting eukaryotic translation initiation factor 4G (eIF4G), the scaffold subunit of eukaryotic translation initiation factor 4F (eIF4F), preferentially impacts short mRNAs with strong closed-loop potential and unstructured 5′ UTRs, exactly the opposite features associated with hyperdependence on the eIF4B/helicases. We propose that short, highly efficient mRNAs preferentially depend on the stimulatory effects of eIF4G-dependent closed-loop assembly. PMID:27601676

  12. Phosphodiesterase 4B negatively regulates endotoxin-activated interleukin-1 receptor antagonist responses in macrophages

    PubMed Central

    Yang, Jing-Xing; Hsieh, Kou-Chou; Chen, Yi-Ling; Lee, Chien-Kuo; Conti, Marco; Chuang, Tsung-Hsien; Wu, Chin-Pyng; Jin, S.-L. Catherine

    2017-01-01

    Activation of TLR4 by lipopolysaccharide (LPS) induces both pro-inflammatory and anti-inflammatory cytokine production in macrophages. Type 4 phosphodiesterases (PDE4) are key cAMP-hydrolyzing enzymes, and PDE4 inhibitors are considered as immunosuppressors to various inflammatory responses. We demonstrate here that PDE4 inhibitors enhance the anti-inflammatory cytokine interleukin-1 receptor antagonist (IL-1Ra) secretion in LPS-activated mouse peritoneal macrophages, and this response was regulated at the transcriptional level rather than an increased IL-1Ra mRNA stability. Studies with PDE4-deficient macrophages revealed that the IL-1Ra upregulation elicited by LPS alone is PKA-independent, whereas the rolipram-enhanced response was mediated by inhibition of only PDE4B, one of the three PDE4 isoforms expressed in macrophages, and it requires PKA but not Epac activity. However, both pathways activate CREB to induce IL-1Ra expression. PDE4B ablation also promoted STAT3 phosphorylation (Tyr705) to LPS stimulation, but this STAT3 activation is not entirely responsible for the IL-1Ra upregulation in PDE4B-deficient macrophages. In a model of LPS-induced sepsis, only PDE4B-deficient mice displayed an increased circulating IL-1Ra, suggesting a protective role of PDE4B inactivation in vivo. These findings demonstrate that PDE4B negatively modulates anti-inflammatory cytokine expression in innate immune cells, and selectively targeting PDE4B should retain the therapeutic benefits of nonselective PDE4 inhibitors. PMID:28383060

  13. The higher level of complexity of K-Ras4B activation at the membrane

    PubMed Central

    Jang, Hyunbum; Banerjee, Avik; Chavan, Tanmay S.; Lu, Shaoyong; Zhang, Jian; Gaponenko, Vadim; Nussinov, Ruth

    2016-01-01

    Is nucleotide exchange sufficient to activate K-Ras4B? To signal, oncogenic rat sarcoma (Ras) anchors in the membrane and recruits effectors by exposing its effector lobe. With the use of NMR and molecular dynamics (MD) simulations, we observed that in solution, farnesylated guanosine 5′-diphosphate (GDP)-bound K-Ras4B is predominantly autoinhibited by its hypervariable region (HVR), whereas the GTP-bound state favors an activated, HVR-released state. On the anionic membrane, the catalytic domain adopts multiple orientations, including parallel (∼180°) and perpendicular (∼90°) alignments of the allosteric helices, with respect to the membrane surface direction. In the autoinhibited state, the HVR is sandwiched between the effector lobe and the membrane; in the active state, with membrane-anchored farnesyl and unrestrained HVR, the catalytic domain fluctuates reinlessly, exposing its effector-binding site. Dimerization and clustering can reduce the fluctuations. This achieves preorganized, productive conformations. Notably, we also observe HVR-autoinhibited K-Ras4B-GTP states, with GDP-bound-like orientations of the helices. Thus, we propose that the GDP/GTP exchange may not be sufficient for activation; instead, our results suggest that the GDP/GTP exchange, HVR sequestration, farnesyl insertion, and orientation/localization of the catalytic domain at the membrane conjointly determine the active or inactive state of K-Ras4B. Importantly, K-Ras4B-GTP can exist in active and inactive states; on its own, GTP binding may not compel K-Ras4B activation.—Jang, H., Banerjee, A., Chavan, T. S, Lu, S., Zhang, J., Gaponenko, V., Nussinov, R. The higher level of complexity of K-Ras4B activation at the membrane. PMID:26718888

  14. Environmental Assessment and Finding of No Significant Impact: Transuranic Waste Retrieval from the 218-W-4B and 218-W-4C Low-Level Burial Grounds, Hanford Site, Richland, Washington

    SciTech Connect

    N /A

    2002-03-22

    The U.S. Department of Energy, Richland Operations Office (DOE-RL) needs to improve management of post-1970, contact-handled (CH) suspect transuranic (TRU) waste containers (primarily drums) that are stacked in modules and covered with soil in the Low-Level Burial Grounds (LLBG).

  15. Essential role for the ATG4B protease and autophagy in bleomycin-induced pulmonary fibrosis

    PubMed Central

    Cabrera, Sandra; Maciel, Mariana; Herrera, Iliana; Nava, Teresa; Vergara, Fabián; Gaxiola, Miguel; López-Otín, Carlos; Selman, Moisés; Pardo, Annie

    2015-01-01

    Autophagy is a critical cellular homeostatic process that controls the turnover of damaged organelles and proteins. Impaired autophagic activity is involved in a number of diseases, including idiopathic pulmonary fibrosis suggesting that altered autophagy may contribute to fibrogenesis. However, the specific role of autophagy in lung fibrosis is still undefined. In this study, we show for the first time, how autophagy disruption contributes to bleomycin-induced lung fibrosis in vivo using an Atg4b-deficient mouse as a model. Atg4b-deficient mice displayed a significantly higher inflammatory response at 7 d after bleomycin treatment associated with increased neutrophilic infiltration and significant alterations in proinflammatory cytokines. Likewise, we found that Atg4b disruption resulted in augmented apoptosis affecting predominantly alveolar and bronchiolar epithelial cells. At 28 d post-bleomycin instillation Atg4b-deficient mice exhibited more extensive and severe fibrosis with increased collagen accumulation and deregulated extracellular matrix-related gene expression. Together, our findings indicate that the ATG4B protease and autophagy play a crucial role protecting epithelial cells against bleomycin-induced stress and apoptosis, and in the regulation of the inflammatory and fibrotic responses. PMID:25906080

  16. Essential role for the ATG4B protease and autophagy in bleomycin-induced pulmonary fibrosis.

    PubMed

    Cabrera, Sandra; Maciel, Mariana; Herrera, Iliana; Nava, Teresa; Vergara, Fabián; Gaxiola, Miguel; López-Otín, Carlos; Selman, Moisés; Pardo, Annie

    2015-04-03

    Autophagy is a critical cellular homeostatic process that controls the turnover of damaged organelles and proteins. Impaired autophagic activity is involved in a number of diseases, including idiopathic pulmonary fibrosis suggesting that altered autophagy may contribute to fibrogenesis. However, the specific role of autophagy in lung fibrosis is still undefined. In this study, we show for the first time, how autophagy disruption contributes to bleomycin-induced lung fibrosis in vivo using an Atg4b-deficient mouse as a model. Atg4b-deficient mice displayed a significantly higher inflammatory response at 7 d after bleomycin treatment associated with increased neutrophilic infiltration and significant alterations in proinflammatory cytokines. Likewise, we found that Atg4b disruption resulted in augmented apoptosis affecting predominantly alveolar and bronchiolar epithelial cells. At 28 d post-bleomycin instillation Atg4b-deficient mice exhibited more extensive and severe fibrosis with increased collagen accumulation and deregulated extracellular matrix-related gene expression. Together, our findings indicate that the ATG4B protease and autophagy play a crucial role protecting epithelial cells against bleomycin-induced stress and apoptosis, and in the regulation of the inflammatory and fibrotic responses.

  17. Discover natural compounds as potential phosphodiesterase-4B inhibitors via computational approaches.

    PubMed

    Li, Jing; Zhou, Nan; Liu, Wen; Li, Jianzong; Feng, Yu; Wang, Xiaoyun; Wu, Chuanfang; Bao, Jinku

    2016-05-01

    cAMP, intracellular cyclic adenosine monophosphate, is a ubiquitous second messenger that plays a key role in many physiological processes. PDE4B which can reduce the cAMP level by hydrolyzing cAMP to 5'-AMP has become a therapeutic target for the treatment of human diseases such as respiratory disorders, inflammation diseases, neurological and psychiatric disorders. However, the use of currently available PDE4B inhibitors is restricted due to serious side effects caused by targeting PDE4D. Hence, we are attempting to find out subfamily-selective PDE4B inhibitors from natural products, using computer-aided approaches such as virtual screening, docking, and molecular dynamics simulation. Finally, four potential PDE4B-selective inhibitors (ZINC67912770, ZINC67912780, ZINC72320169, and ZINC28882432) were found. Compared to the reference drug (roflumilast), they scored better during the virtual screening process. Binding free energy for them was -317.51, -239.44, -215.52, and -165.77 kJ/mol, better than -129.05 kJ/mol of roflumilast. The pharmacophore model of the four candidate inhibitors comprised six features, including one hydrogen bond donor, four hydrogen bond acceptors, and one aromatic ring feature. It is expected that our study will pave the way for the design of potent PDE4B-selective inhibitors of new drugs to treat a wide variety of diseases such as asthma, COPD, psoriasis, depression, etc.

  18. A novel ATG4B antagonist inhibits autophagy and has a negative impact on osteosarcoma tumors.

    PubMed

    Akin, Debra; Wang, S Keisin; Habibzadegah-Tari, Pouran; Law, Brian; Ostrov, David; Li, Min; Yin, Xiao-Ming; Kim, Jae-Sung; Horenstein, Nicole; Dunn, William A

    2014-01-01

    Autophagy has been implicated in the progression and chemoresistance of various cancers. In this study, we have shown that osteosarcoma Saos-2 cells lacking ATG4B, a cysteine proteinase that activates LC3B, are defective in autophagy and fail to form tumors in mouse models. By combining in silico docking with in vitro and cell-based assays, we identified small compounds that suppressed starvation-induced protein degradation, LC3B lipidation, and formation of autophagic vacuoles. NSC185058 effectively inhibited ATG4B activity in vitro and in cells while having no effect on MTOR and PtdIns3K activities. In addition, this ATG4B antagonist had a negative impact on the development of Saos-2 osteosarcoma tumors in vivo. We concluded that tumor suppression was due to a reduction in ATG4B activity, since we found autophagy suppressed within treated tumors and the compound had no effects on oncogenic protein kinases. Our findings demonstrate that ATG4B is a suitable anti-autophagy target and a promising therapeutic target to treat osteosarcoma.

  19. A novel ATG4B antagonist inhibits autophagy and has a negative impact on osteosarcoma tumors

    PubMed Central

    Akin, Debra; Wang, S Keisin; Habibzadegah-Tari, Pouran; Law, Brian; Ostrov, David; Li, Min; Yin, Xiao-Ming; Kim, Jae-Sung; Horenstein, Nicole; Dunn, William A

    2014-01-01

    Autophagy has been implicated in the progression and chemoresistance of various cancers. In this study, we have shown that osteosarcoma Saos-2 cells lacking ATG4B, a cysteine proteinase that activates LC3B, are defective in autophagy and fail to form tumors in mouse models. By combining in silico docking with in vitro and cell-based assays, we identified small compounds that suppressed starvation-induced protein degradation, LC3B lipidation, and formation of autophagic vacuoles. NSC185058 effectively inhibited ATG4B activity in vitro and in cells while having no effect on MTOR and PtdIns3K activities. In addition, this ATG4B antagonist had a negative impact on the development of Saos-2 osteosarcoma tumors in vivo. We concluded that tumor suppression was due to a reduction in ATG4B activity, since we found autophagy suppressed within treated tumors and the compound had no effects on oncogenic protein kinases. Our findings demonstrate that ATG4B is a suitable anti-autophagy target and a promising therapeutic target to treat osteosarcoma. PMID:25483883

  20. Wetting of microstructured alumina fabricated by epitaxial growth of Al4B2O9 whiskers

    NASA Astrophysics Data System (ADS)

    Wang, Yifeng; Feng, Jicai; Chen, Zhe; Song, Xiaoguo; Cao, Jian

    2015-12-01

    Topographical microstructures were fabricated on alumina by epitaxial growth of Al4B2O9 whiskers in air. The products were characterized via scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The whiskers were found to grow along the [0 0 1] crystallographic direction, and the lattice mismatch between Al2O3 and Al4B2O9 was determined to be 0.03%. The wetting of the Al4B2O9-whisker-coated surfaces by Ag-36.7Cu-8.0Ti at.% alloy was studied. The time needed to reach the equilibrium stage reduced as the temperature increased, and the final contact angle for liquid alloy on the rough surface was 27° at 880 °C. The wetting dynamics of the whiskers coated surfaces was investigated. After wetting, a whisker-interconnected region was formed between alumina and the alloy.

  1. Alternative pathways for association and dissociation of the calmodulin-binding domain of plasma membrane Ca(2+)-ATPase isoform 4b (PMCA4b).

    PubMed

    Penniston, John T; Caride, Ariel J; Strehler, Emanuel E

    2012-08-24

    The calmodulin (CaM)-binding domain of isoform 4b of the plasma membrane Ca(2+) -ATPase (PMCA) pump is represented by peptide C28. CaM binds to either PMCA or C28 by a mechanism in which the primary anchor residue Trp-1093 binds to the C-terminal lobe of the extended CaM molecule, followed by collapse of CaM with the N-terminal lobe binding to the secondary anchor Phe-1110 (Juranic, N., Atanasova, E., Filoteo, A. G., Macura, S., Prendergast, F. G., Penniston, J. T., and Strehler, E. E. (2010) J. Biol. Chem. 285, 4015-4024). This is a relatively rapid reaction, with an apparent half-time of ~1 s. The dissociation of CaM from PMCA4b or C28 is much slower, with an overall half-time of ~10 min. Using targeted molecular dynamics, we now show that dissociation of Ca(2+)-CaM from C28 may occur by a pathway in which Trp-1093, although deeply embedded in a pocket in the C-terminal lobe of CaM, leaves first. The dissociation begins by relatively rapid release of Trp-1093, followed by very slow release of Phe-1110, removal of C28, and return of CaM to its conformation in the free state. Fluorescence measurements and molecular dynamics calculations concur in showing that this alternative path of release of the PMCA4b CaM-binding domain is quite different from that of binding. The intermediate of dissociation with exposed Trp-1093 has a long lifetime (minutes) and may keep the PMCA primed for activation.

  2. Identification of New ATG4B Inhibitors Based on a Novel High-Throughput Screening Platform.

    PubMed

    Xu, Danqing; Xu, Zhiheng; Han, Li; Liu, Cheng; Zhou, Zheng; Qiu, Zongxing; Lin, Xianfeng; Tang, Guozhi; Shen, Hong; Aebi, Johannes; Riemer, Claus; Kuhn, Bernd; Stahl, Martin; Mark, David; Qin, Ning; Ding, Haiyuan

    2017-04-01

    Autophagy is an evolutionarily conserved homeostasis process through which aggregated proteins or damaged organelles are enveloped in a double-membrane structure called an autophagosome and then digested in a lysosome-dependent manner. Growing evidence suggests that malfunction of autophagy contributes to the pathogenesis of a variety of diseases, including cancer, viral infection, and neurodegeneration. However, autophagy is a complicated process, and understanding of the relevance of autophagy to disease is limited by lack of specific and potent autophagy modulators. ATG4B, a Cys-protease that cleaves ATG8 family proteins, such as LC3B, is a key protein in autophagosome formation and maturation process. A novel time-resolved fluorescence resonance energy transfer (TR-FRET) assay measuring protease activity of ATG4B was developed, validated, and adapted into a high-throughput screening (HTS) format. HTS was then conducted with a Roche focus library of 57,000 compounds. After hit confirmation and a counterscreen to filter out fluorescence interference compounds, 267 hits were confirmed, constituting a hit rate of 0.49%. Furthermore, among 65 hits with an IC50 < 50 µM, one compound mimics the LC3 peptide substrate (-TFG-). Chemistry modification based on this particular hit gave preliminary structure activity relationship (SAR) resulting in a compound with a 10-fold increase in potency. This compound forms a stable covalent bond with Cys74 of ATG4B in a 1:1 ratio as demonstrated by liquid chromatography/tandem mass spectrometry (LC/MS/MS). Furthermore, this compound displayed cellular ATG4B inhibition activity. Overall, the novel TR-FRET ATG4B protease assay plus counterscreen assay provides a robust platform to identify ATG4B inhibitors, which would help to elucidate the mechanism of the autophagy pathway and offer opportunities for drug discovery.

  3. Hepatitis C Virus NS4B Can Suppress STING Accumulation To Evade Innate Immune Responses

    PubMed Central

    Wen, Yahong; Shu, Chang; Han, Qingxia; Konan, Kouacou V.; Li, Pingwei; Kao, C. Cheng

    2015-01-01

    ABSTRACT The cyclic dinucleotide 2′,3′-cGAMP can bind the adaptor protein STING (stimulator of interferon [IFN] genes) to activate the production of type I IFNs and proinflammatory cytokines. We found that cGAMP added to the culture medium could suppress the replication of the hepatitis C virus (HCV) genotype 1b strain Con1 subgenomic replicon in human hepatoma cells. Knockdown of STING expression diminished the inhibitory effect on replicon replication, while overexpression of STING enhanced the inhibitory effects of cGAMP. The addition of cGAMP into 1b/Con1 replicon cells significantly increased the expression of type I IFNs and antiviral interferon-stimulated genes. Unexpectedly, replication of the genotype 2a JFH1 replicon and infectious JFH1 virus was less sensitive to the inhibitory effect of cGAMP than was that of 1b/Con1 replicon. Using chimeric replicons, 2a NS4B was identified to confer resistance to cGAMP. Transient expression of 2a NS4B resulted in a pronounced inhibitory effect on STING-mediated beta IFN (IFN-β) reporter activation compared to that of 1b NS4B. 2a NS4B was found to suppress STING accumulation in a dose-dependent manner. The predicted transmembrane domain of 2a NS4B was required to inhibit STING accumulation. These results demonstrate a novel genotype-specific inhibition of the STING-mediated host antiviral immune response. IMPORTANCE The cyclic dinucleotide cGAMP was found to potently inhibit the replication of HCV genotype 1b Con1 replicon but was less effective for the 2a/JFH1 replicon and infectious JFH1 virus. The predicted transmembrane domain in 2a NS4B was shown to be responsible for the decreased sensitivity to cGAMP. The N terminus of NS4B has been reported to suppress STING-mediated signaling by disrupting the interaction of STING and TBK1 and/or MAVS. We show that 2a/JFH1 NS4B has an additional mechanism to evade STING signaling through suppressing STING accumulation. PMID:26468527

  4. Genome-first approach diagnosed Cabezas syndrome via novel CUL4B mutation detection.

    PubMed

    Okamoto, Nobuhiko; Watanabe, Miki; Naruto, Takuya; Matsuda, Keiko; Kohmoto, Tomohiro; Saito, Masako; Masuda, Kiyoshi; Imoto, Issei

    2017-01-01

    Cabezas syndrome is a syndromic form of X-linked intellectual disability primarily characterized by a short stature, hypogonadism and abnormal gait, with other variable features resulting from mutations in the CUL4B gene. Here, we report a clinically undiagnosed 5-year-old male with severe intellectual disability. A genome-first approach using targeted exome sequencing identified a novel nonsense mutation [NM_003588.3:c.2698G>T, p.(Glu900*)] in the last coding exon of CUL4B, thus diagnosing this patient with Cabezas syndrome.

  5. Genome-first approach diagnosed Cabezas syndrome via novel CUL4B mutation detection

    PubMed Central

    Okamoto, Nobuhiko; Watanabe, Miki; Naruto, Takuya; Matsuda, Keiko; Kohmoto, Tomohiro; Saito, Masako; Masuda, Kiyoshi; Imoto, Issei

    2017-01-01

    Cabezas syndrome is a syndromic form of X-linked intellectual disability primarily characterized by a short stature, hypogonadism and abnormal gait, with other variable features resulting from mutations in the CUL4B gene. Here, we report a clinically undiagnosed 5-year-old male with severe intellectual disability. A genome-first approach using targeted exome sequencing identified a novel nonsense mutation [NM_003588.3:c.2698G>T, p.(Glu900*)] in the last coding exon of CUL4B, thus diagnosing this patient with Cabezas syndrome. PMID:28144446

  6. Mutation in the AP4B1 gene cause hereditary spastic paraplegia type 47 (SPG47) .

    PubMed

    Bauer, Peter; Leshinsky-Silver, Esther; Blumkin, Lubov; Schlipf, Nina; Schröder, Christopher; Schicks, Julia; Lev, Dorit; Riess, Olaf; Lerman-Sagie, Tally; Schöls, Ludger

    2012-02-01

    We recently identified a new locus for spastic paraplegia type 47 (SPG47) in a consanguineous Arabic family with two affected siblings with progressive spastic paraparesis,intellectual disability, seizures, periventricular white matter changes and thin corpus callosum. Using exome sequencing, we now identified a novel AP4B1 frameshift mutation (c.664delC) in this family. This mutation was homozygous in both affected siblings and heterozygous in both parents. The mutant allele was absent in 316 Caucasian and 200 ethnically matched control chromosomes. We propose that AP4B1 mutations cause SPG47 and should be considered in early onset spastic paraplegia with intellectual disability.

  7. Overview of the Lockheed Martin Compact Fusion Reactor (CFR) T4B Experiment

    NASA Astrophysics Data System (ADS)

    McGuire, Thomas

    2016-10-01

    The Lockheed Martin Compact Fusion Reactor (CFR) Program endeavors to quickly develop a compact fusion power plant with favorable commercial economics and military utility. The CFR uses a diamagnetic, high beta, magnetically encapsulated, linear ring cusp plasma confinement scheme. The goal of the T4B experiment is to demonstrate a suitable plasma target for heating experiments and to characterize the behavior of plasma sources in the CFR configuration. The design of the T4B experiment will be presented, including discussion of predicted behavior, plasma sources, heating mechanisms, diagnostics suite and relevant numerical modeling. ©2016 Lockheed Martin Corporation. All Rights Reserved.

  8. Loss of p15/Ink4b accompanies tumorigenesis triggered by complex DNA double-strand breaks

    PubMed Central

    Camacho, Cristel V.; Mukherjee, Bipasha; McEllin, Brian; Ding, Liang-Hao; Hu, Burong; Habib, Amyn A.; Xie, Xian-Jin; Nirodi, Chaitanya S.; Saha, Debabrata; Story, Michael D.; Balajee, Adayabalam S.; Bachoo, Robert M.; Boothman, David A.; Burma, Sandeep

    2010-01-01

    DNA double-strand breaks (DSBs) are the most deleterious lesion inflicted by ionizing radiation. Although DSBs are potentially carcinogenic, it is not clear whether complex DSBs that are refractory to repair are more potently tumorigenic compared with simple breaks that can be rapidly repaired, correctly or incorrectly, by mammalian cells. We previously demonstrated that complex DSBs induced by high-linear energy transfer (LET) Fe ions are repaired slowly and incompletely, whereas those induced by low-LET gamma rays are repaired efficiently by mammalian cells. To determine whether Fe-induced DSBs are more potently tumorigenic than gamma ray-induced breaks, we irradiated ‘sensitized’ murine astrocytes that were deficient in Ink4a and Arf tumor suppressors and injected the surviving cells subcutaneously into nude mice. Using this model system, we find that Fe ions are potently tumorigenic, generating tumors with significantly higher frequency and shorter latency compared with tumors generated by gamma rays. Tumor formation by Fe-irradiated cells is accompanied by rampant genomic instability and multiple genomic changes, the most interesting of which is loss of the p15/Ink4b tumor suppressor due to deletion of a chromosomal region harboring the CDKN2A and CDKN2B loci. The additional loss of p15/Ink4b in tumors derived from cells that are already deficient in p16/Ink4a bolsters the hypothesis that p15 plays an important role in tumor suppression, especially in the absence of p16. Indeed, we find that reexpression of p15 in tumor-derived cells significantly attenuates the tumorigenic potential of these cells, indicating that p15 loss may be a critical event in tumorigenesis triggered by complex DSBs. PMID:20663777

  9. Preparation of Al8B4C7 composite materials by using oxide raw materials

    NASA Astrophysics Data System (ADS)

    Zhu, H. X.; Pan, C.; Deng, C. J.; Yuan, W. J.

    2011-10-01

    Al8B4C7 composites materials were prepared by using Al, B2O3 and C as raw materials. The effect of sintering temperature and different additives (Al and C) on Al8B4C7 composites materials were investigated. The Al8B4C7 composites materials were characterized from microstructure, apparent porosity, bulk density and compressive strength. The results demonstrated that the increasing of sintering temperatures could make the samples denser and improve compressive strength. The optimal sintering temperature was 1700 °C, and the main phase composition of Al8B4C7 composites materials were Al8B4C7 and Al2O3. Al additive could improve the properties while C additive played an harmful role. The Al8B4C7 grains were irregular flake and the size was 2~4 μm.

  10. [Knockdown of Larp4b in Lin(-) cells does not affect the colony forming ability of mouse hematopoietic cells].

    PubMed

    Wang, Xiao-Juan; Pang, Ya-Kun; Cheng, Hui; Dong, Fang; Liang, Hao-Yue; Zhang, Ying-Chi; Wang, Xiao-Min; Xu, Jing; Cheng, Tao; Yuan, Wei-Ping

    2013-06-01

    Larp4b is a member of the LARP family, which can interact with RNA and generally stimulate the translation of mRNA. Abnormal expression of Larp4b can be found in leukemia patients in our previous study. This study was purposed to detect the relative expression of Larp4b mRNA in different subpopulations of mouse hematopoietic cells, to construct lentivirus vector containing shLarp4b targeting mouse gene Larp4b and to explore its effects on mouse Lin(-) cells infected with shLarp4b by lentivirus. SF-LV-shLarP4b-EGFP and control vectors were constructed and two-plasmid lentivirus packing system was used to transfect 293T cells. After 48 h and 72 h, lentivirus SF-LV-shLarp4b-EGFP was harvested and was used to infect Lin(-) cells. After 48 h, EGFP(+) cells was sorted by flow cytometry (FCM). Meanwhile, semi-quantitative real time-PCR, AnnexinV-PE/7-AAD staining, PI staining and colony forming cell assay (CFC) were performed to determine the expression of Larp4b and its effect on the proliferation of hematopoietic progenitor cells. The results showed that Larp4b was highly expressed in myeloid cells. SF-LV-shLarp4b-EGFP was successfully constructed according to the restriction endonuclease digestion assay. RT-PCR confirmed that Larp4b was efficiently knockdown in mouse Lin(-) cells. The low expression of Larp4b did not affect the colony forming number, the apoptosis and cell cycle of Lin(-) cells. It is concluded that knockdown of Larp4b in mouse Lin(-) cells do not contribute to the colony forming ability and the growth of Lin(-) cells in vitro. This useful knockdown system will be used to study in vivo Larp4b in future.

  11. Potent L-lactic acid assimilation of the fermentative and heterothallic haploid yeast Saccharomyces cerevisiae NAM34-4C.

    PubMed

    Tomitaka, Masataka; Taguchi, Hisataka; Matsuoka, Masayoshi; Morimura, Shigeru; Kida, Kenji; Akamatsu, Takashi

    2014-01-01

    We screened an industrial thermotolerant Saccharomyces cerevisiae strain, KF7, as a potent lactic-acid-assimilating yeast. Heterothallic haploid strains KF7-5C and KF7-4B were obtained from the tetrads of the homothallic yeast strain KF7. The inefficient sporulation and poor spore viability of the haploid strains were improved by two strategies. The first strategy was as follows: (i) the KF7-5C was crossed with the laboratory strain SH6710; (ii) the progenies were backcrossed with KF7-5C three times; and (iii) the progenies were inbred three times to maintain a genetic background close to that of KF7. The NAM12 diploid between the cross of the resultant two strains, NAM11-9C and NAM11-13A, showed efficient sporulation and exhibited excellent growth in YPD medium (pH 3.5) at 35°C with 1.4-h generation time, indicating thermotolerance and acid tolerance. The second strategy was successive intrastrain crosses. The resultant two strains, KFG4-6B and KFG4-4B, showed excellent mating capacity. A spontaneous mutant of KFG4-6B, KFG4-6BD, showed a high growth rate with a generation time of 1.1 h in YPD medium (pH 3.0) at 35°C. The KFG4-6BD strain produced ascospores, which were crossed with NAM11-2C and its progeny to produce tetrads. These tetrads were crossed with KFG4-4B to produce NAM26-14A and NAM26-15A. The latter strain had a generation time of 1.6 h at 35°C in pH 2.5, thus exhibiting further thermotolerance and acid tolerance. A progeny from a cross of NAM26-14A and NAM26-15A yielded the strain NAM34-4C, which showed potent lactic acid assimilation and high transformation efficiency, better than those of a standard laboratory strain.

  12. 32 CFR 1630.42 - Class 4-C: Alien or dual national.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Class 4-C: Alien or dual national. 1630.42... CLASSIFICATION RULES § 1630.42 Class 4-C: Alien or dual national. In Class 4-C shall be placed any registrant who... service in the United States. (b) Is an alien and who has departed from the United States prior to...

  13. 32 CFR 1630.42 - Class 4-C: Alien or dual national.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Class 4-C: Alien or dual national. 1630.42... CLASSIFICATION RULES § 1630.42 Class 4-C: Alien or dual national. In Class 4-C shall be placed any registrant who... service in the United States. (b) Is an alien and who has departed from the United States prior to...

  14. 32 CFR 1630.42 - Class 4-C: Alien or dual national.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Class 4-C: Alien or dual national. 1630.42... CLASSIFICATION RULES § 1630.42 Class 4-C: Alien or dual national. In Class 4-C shall be placed any registrant who... service in the United States. (b) Is an alien and who has departed from the United States prior to...

  15. 32 CFR 1630.42 - Class 4-C: Alien or dual national.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Class 4-C: Alien or dual national. 1630.42... CLASSIFICATION RULES § 1630.42 Class 4-C: Alien or dual national. In Class 4-C shall be placed any registrant who... service in the United States. (b) Is an alien and who has departed from the United States prior to...

  16. 32 CFR 1630.42 - Class 4-C: Alien or dual national.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Class 4-C: Alien or dual national. 1630.42... CLASSIFICATION RULES § 1630.42 Class 4-C: Alien or dual national. In Class 4-C shall be placed any registrant who... service in the United States. (b) Is an alien and who has departed from the United States prior to...

  17. The pathogenesis-related protein PR-4b from Theobroma cacao presents RNase activity, Ca2+ and Mg2+ dependent-DNase activity and antifungal action on Moniliophthora perniciosa

    PubMed Central

    2014-01-01

    Background The production and accumulation of pathogenesis-related proteins (PR proteins) in plants in response to biotic or abiotic stresses is well known and is considered as a crucial mechanism for plant defense. A pathogenesis-related protein 4 cDNA was identified from a cacao-Moniliophthora perniciosa interaction cDNA library and named TcPR-4b. Results TcPR-4b presents a Barwin domain with six conserved cysteine residues, but lacks the chitin-binding site. Molecular modeling of TcPR-4b confirmed the importance of the cysteine residues to maintain the protein structure, and of several conserved amino acids for the catalytic activity. In the cacao genome, TcPR-4b belonged to a small multigene family organized mainly on chromosome 5. TcPR-4b RT-qPCR analysis in resistant and susceptible cacao plants infected by M. perniciosa showed an increase of expression at 48 hours after infection (hai) in both cacao genotypes. After the initial stage (24-72 hai), the TcPR-4b expression was observed at all times in the resistant genotypes, while in the susceptible one the expression was concentrated at the final stages of infection (45-90 days after infection). The recombinant TcPR-4b protein showed RNase, and bivalent ions dependent-DNase activity, but no chitinase activity. Moreover, TcPR-4b presented antifungal action against M. perniciosa, and the reduction of M. perniciosa survival was related to ROS production in fungal hyphae. Conclusion To our knowledge, this is the first report of a PR-4 showing simultaneously RNase, DNase and antifungal properties, but no chitinase activity. Moreover, we showed that the antifungal activity of TcPR-4b is directly related to RNase function. In cacao, TcPR-4b nuclease activities may be related to the establishment and maintenance of resistance, and to the PCD mechanism, in resistant and susceptible cacao genotypes, respectively. PMID:24920373

  18. Intrathecal injection of phosphodiesterase 4B-specific siRNA attenuates neuropathic pain in rats with L5 spinal nerve ligation.

    PubMed

    Ji, Qing; Di, Yan; He, Xiaoyun; Liu, Qingzhen; Liu, Jian; Li, Weiyan; Zhang, Lidong

    2016-02-01

    Phosphodiesterase 4 (PDE4) is an adenosine cyclic 3,5-monophosphate-specific degradative enzyme, which is closely associated with the inflammatory response. Among its four subtypes (A-D), it remains unclear which one exerts suppressive effects on inflammation and reduces neuropathic pain. The present study aimed to examine the modulation of neuroinflammation by PDE4 subtypes in the spinal cord of a rat model of L5 spinal nerve ligation (SNL)-induced neuropathic pain. The expression levels of PDE4A-D were measured in the lumbar spinal cords of naïve rats. The rats were then divided into seven groups: The sham group (sham surgery + saline), the saline group (SNL + saline), the vehicle group (SNL + Lipofectamine® RNAiMAX), the mismatch small interfering (si)RNA group (SNL + mismatch siRNA), the PDE4A-siRNA group (SNL + PDE4A-siRNA), the PDE4B-siRNA group (SNL + PDE4B-siRNA) and the PDE4D-siRNA group (SNL + PDE4D-siRNA). In order to determine behavioral changes, mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were recorded. The mRNA and protein expression levels of PDE4s were also detected. Furthermore, the association between behavioral changes and individual subtypes of PDE4 were studied following intrathecal administration of PDE4A, B and D-specific siRNA. The expression levels of protein kinases, including phosphorylated-extracellular signal-regulated kinases (p-ERK), and inflammatory cytokines were measured, in order to explore the underlying mechanisms. Subtypes A, B and D, but not C, were detected in the naïve rats. After SNL, both MWT and TWL were reduced. The mRNA and protein expression levels of PDE4A, B and D were significantly upregulated after 2, 4, 6 and 8 days of SNL. Subtype-specific siRNA significantly suppressed the elevated expression levels; however, only rats treated with PDE4B siRNA exhibited improved MWT and TWL. Further analysis of the PDE4B siRNA-treated rats demonstrated that 8 days after SNL, the intensity of p

  19. Identification of an NTPase motif in classical swine fever virus NS4B protein

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical swine fever (CSF) is a highly contagious and often fatal disease of swine caused by CSF virus (CSFV), a positive sense single-stranded RNA virus in the genus Pestivirus of the Flaviviridae family. Here, we have identified, within CSFV non-structural (NS) protein NS4B, conserved sequence el...

  20. Identification of immunogenic MAGED4B peptides for vaccine development in oral cancer immunotherapy.

    PubMed

    Lim, Kue Peng; Chun, Nicole Ai Leng; Gan, Chai Phei; Teo, Soo-Hwang; Rahman, Zainal Ariff Abdul; Abraham, Mannil Thomas; Zain, Rosnah Binti; Ponniah, Sathibalan; Cheong, Sok Ching

    2014-01-01

    The ever-increasing number of tumor-associated antigens has provided a major stimulus for the development of therapeutic peptides vaccines. Tumor-associated peptides can induce high immune response rates and have been developed as vaccines for several types of solid tumors, and many are at various stages of clinical testing. MAGED4B, a melanoma antigen, is overexpressed in oral squamous cell carcinoma (OSCC) and this expression promotes proliferation and cell migration. In this study, we have identified 9 short peptides derived from MAGED4B protein that are restricted in binding to the HLA subtypes common in the Asian population (HLA-A2, A11, and A24). The peptides had good binding affinity with the MHC-Class I molecules and stimulated ex-vivo IFN-gamma and Granzyme-B production in blood samples from OSCC patients, suggesting that they are immunogenic. Further, T cells stimulated with peptide-pulsed dendritic cells showed enhanced T-cell cytotoxic activity against MAGED4B-overexpressing OSCC cell lines. In summary, we have identified MAGED4B peptides that induce anti-tumor immune responses advocating that they could be further developed as vaccine candidates for the treatment of OSCC.

  1. 16 CFR 1508.5 - Component spacing test method for § 1508.4(b).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Component spacing test method for § 1508.4(b). 1508.5 Section 1508.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR FULL-SIZE BABY CRIBS § 1508.5 Component spacing test method...

  2. 20. FOUR 4B17Gs BEING CONVERTED TO F9Cs. Photographic copy of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. FOUR 4B-17Gs BEING CONVERTED TO F-9Cs. Photographic copy of historic photograph. Jan.-June 1947 OAMA (original print located at Ogden Air Logistics Center, Hill Air Force Base, Utah). Photographer unknown. - Hill Field, Airplane Repair Hangars No. 1-No. 4, 5875 Southgate Avenue, Layton, Davis County, UT

  3. PSD-95 mediates membrane clustering of the human plasma membrane Ca2+ pump isoform 4b.

    PubMed

    Padányi, Rita; Pászty, Katalin; Strehler, Emanuel E; Enyedi, Agnes

    2009-06-01

    Besides the control of global calcium changes, specific plasma membrane calcium ATPase (PMCA) isoforms are involved in the regulation of local calcium signals. Although local calcium signaling requires the confinement of signaling molecules into microdomains, little is known about the specific organization of PMCA molecules within the plasma membrane. Here we show that co-expression with the postsynaptic density-95 (PSD-95) scaffolding protein increased the plasma membrane expression of PMCA4b and redistributed the pump into clusters. The clustering of PMCA4b was fully dependent on the presence of its PDZ-binding sequence. Using the fluorescence recovery after photobleaching (FRAP) technique, we show that the lateral membrane mobility of the clustered PMCA4b is significantly lower than that of the non-clustered molecules. Disruption of the actin-based cytoskeleton by cytochalasin D resulted in increased cluster size. Our results suggest that PSD-95 promotes the formation of high-density PMCA4b microdomains in the plasma membrane and that the membrane cytoskeleton plays an important role in the regulation of this process.

  4. 75 FR 54153 - International Conference on Harmonisation; Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... Recommendation of Pharmacopoeial Texts for Use in the International Conference on Harmonisation Regions; Annex 11... guidance entitled ``Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the ICH Regions... Electrophoresis General Chapter harmonized text from each of the three pharmacopoeias (United States,...

  5. 75 FR 18509 - International Conference on Harmonisation; Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-12

    ... Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... Texts for Use in the ICH Regions; Annex 10: Polyacrylamide Gel Electrophoresis General Chapter.'' The... ICH Q4B evaluation of the Polyacrylamide Gel Electrophoresis General Chapter harmonized text from...

  6. 75 FR 17148 - International Conference on Harmonisation; Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... availability of a guidance entitled ``Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the... Dissolution Test General Chapter harmonized text from each of the three pharmacopoeias (United...

  7. 75 FR 53973 - International Conference on Harmonisation; Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-02

    ... Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... availability of a guidance entitled ``Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the... Sieving General Chapter harmonized text from each of the three pharmacopoeias (United States,...

  8. 75 FR 17147 - International Conference on Harmonisation; Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... availability of a guidance entitled ``Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the... Friability General Chapter harmonized text from each of the three pharmacopoeias (United States,...

  9. DISC1, PDE4B, and NDE1 at the centrosome and synapse

    SciTech Connect

    Bradshaw, Nicholas J.; Ogawa, Fumiaki; Antolin-Fontes, Beatriz; Chubb, Jennifer E.; Carlyle, Becky C.; Christie, Sheila; Claessens, Antoine; Porteous, David J.; Millar, J. Kirsty

    2008-12-26

    Disrupted-In-Schizophrenia 1 (DISC1) is a risk factor for schizophrenia and other major mental illnesses. Its protein binding partners include the Nuclear Distribution Factor E Homologs (NDE1 and NDEL1), LIS1, and phosphodiesterases 4B and 4D (PDE4B and PDE4D). We demonstrate that NDE1, NDEL1 and LIS1, together with their binding partner dynein, associate with DISC1, PDE4B and PDE4D within the cell, and provide evidence that this complex is present at the centrosome. LIS1 and NDEL1 have been previously suggested to be synaptic, and we now demonstrate localisation of DISC1, NDE1, and PDE4B at synapses in cultured neurons. NDE1 is phosphorylated by cAMP-dependant Protein Kinase A (PKA), whose activity is, in turn, regulated by the cAMP hydrolysis activity of phosphodiesterases, including PDE4. We propose that DISC1 acts as an assembly scaffold for all of these proteins and that the NDE1/NDEL1/LIS1/dynein complex is modulated by cAMP levels via PKA and PDE4.

  10. The Crystal Structure of Cytochrome P450 4B1 (CYP4B1) Monoxygenase Complexed with Octane Discloses Several Structural Adaptations for ω-Hydroxylation.

    PubMed

    Hsu, Mei-Hui; Baer, Brian R; Rettie, Allan E; Johnson, Eric F

    2017-02-06

    P450 family 4 fatty acid ω-hydroxylases preferentially oxygenate primary C-H bonds over adjacent, energetically favored secondary C-H bonds, but the mechanism explaining this intriguing preference is unclear. To this end, the structure of rabbit P450 4B1 complexed with its substrate octane was determined by X-ray crystallography to define features of the active site that contribute to a preference for ω-hydroxylation. The structure indicated that octane is bound in a narrow active site cavity that limits access of the secondary C-H bond to the reactive intermediate. A highly conserved sequence motif on helix I contributes to positioning the terminal carbon of octane for ω-hydroxylation. Glu-310 of this motif auto-catalytically forms an ester bond with the heme 5-methyl, and the immobilized E310 contributes to substrate positioning. The preference for ω-hydroxylation was decreased in a E310A mutant having a shorter side-chain, but overall rates of metabolism were retained. E310D and E310Q substitutions having longer side-chains exhibit lower overall rates, likely due to higher conformational entropy for these residues, but they retained high preferences for octane ω-hydroxylation. Sequence comparisons indicated that active-site residues constraining octane for ω-hydroxylation are conserved in family 4 P450s. Moreover, the heme 7-propionate is positioned in the active site and provides additional restraints on substrate binding. In conclusion, P450 4B1 exhibits structural adaptations for ω-hydroxylation that include changes in the conformation of the heme and changes in a highly conserved helix I motif that is associated with selective oxygenation of un-activated primary C-H bonds.

  11. Instructions for the use of the CIVM-Jet 4C finite-strain computer code to calculate the transient structural responses of partial and/or complete arbitrarily-curved rings subjected to fragment impact

    NASA Technical Reports Server (NTRS)

    Rodal, J. J. A.; French, S. E.; Witmer, E. A.; Stagliano, T. R.

    1979-01-01

    The CIVM-JET 4C computer program for the 'finite strain' analysis of 2 d transient structural responses of complete or partial rings and beams subjected to fragment impact stored on tape as a series of individual files. Which subroutines are found in these files are described in detail. All references to the CIVM-JET 4C program are made assuming that the user has a copy of NASA CR-134907 (ASRL TR 154-9) which serves as a user's guide to (1) the CIVM-JET 4B computer code and (2) the CIVM-JET 4C computer code 'with the use of the modified input instructions' attached hereto.

  12. Two-Dimensional Nb-Based M 4 C 3 Solid Solutions (MXenes)

    DOE PAGES

    Yang, Jian; Naguib, Michael; Ghidiu, Michael; ...

    2015-10-15

    Two new two-dimensional Nb4C3-based solid solutions (MXenes), (Nb0.8,Ti0.2)4C3Tx and (Nb0.8,Zr0.2)4C3Tx (where T is a surface termination) were synthesizedas confirmed by X-ray diffractionfrom their corresponding MAX phase precursors (Nb0.8,Ti0.2)4AlC3 and (Nb0.8,Zr0.2)4AlC3. In our report we discuss Zr-containing MXene. We also studied intercalation of Li ions into these two compositions, and Nb4C3Tx in order to determine the potential of those materials for energy storage applications. Lithiation and delithiation peaks at 2.26 and 2.35 V, respectively, appeared in the case of Nb4C3Tx, but were not present in Nb2CTx. After 20 cycles at a rate of C/4, the specific capacities of (Nb0.8,Ti0.2)4C3Txand (Nb0.8,Ti0.2)4C3Tx weremore » 158 and 132 mAh/g, respectively, both slightly lower than the capacity of Nb4C3Tx.« less

  13. Synthesis and Electrochemical Properties of LiFePO4/C for Lithium Ion Batteries.

    PubMed

    Gao, Hong; Wang, Jiazhao; Yin, Shengyu; Zheng, Hao; Wang, Shengfu; Feng, Chuanqi; Wang, Shiquan

    2015-03-01

    LiFePO4/C was prepared through a facile rheological phase reaction method by using Fe3(PO4)2, Li3PO4 · 8H2O, and glucose as reactants. The LiFePO4/C samples were characterized by X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. The electrochemical properties of the samples were investigated. The results show that the LiFePO4/C samples have single-phase olivine-type structure, and their particles feature a spherical shape. The carbon coating on the particles of LiFePO4 is about 1.8% of the LiFePO4/C by weight. The particle size was distributed from 0.2 to 1 µm. The initial discharge capacity of LiFePO4/C reached 154 mA h/g at 0.1 C. The retained discharge capacity of LiFePO4/C was 152.9 mA h g(-1) after 50 cycles. The LiFePO4/C also showed better cycling performance than that of the bare LiPeO4 at a higher charge/discharge rate (1 C). The LIFePO4/C prepared in this way could be a promising cathode material for lithium ion battery application.

  14. Development and characterization of a replicon-based phenotypic assay for assessing HCV NS4B from clinical isolates.

    PubMed

    Rajyaguru, Sonal; Yang, Huiling; Martin, Ross; Miller, Michael D; Mo, Hongmei

    2013-11-01

    The hepatitis C virus (HCV) NS4B inhibitors have shown potent inhibition of HCV replication in vitro. To assess the effect of viral diversity on the susceptibility to NS4B inhibitors, genotype (GT)-specific GT1a and GT1b replicon shuttle vectors were designed and created for cloning HCV NS4B genes from clinical isolates. For the GT1b NS4B shuttle vector, the S2204I adaptive mutation was introduced in NS5A to improve replication due to the replacement of the K1846T adaptive mutation in NS4B with NS4B from the clinical isolates. In addition to the adaptive mutations, a newly identified Huh-7 cell line, Huh-7-1C, which is highly permissive for both GT1a and GT1b replication, was used to further enhance the replication levels. HCV NS4B gene from clinical isolates was amplified and inserted into the corresponding GT1a and GT1b modified lab strain chimeric replicons. GT1a and GT1b chimeric replicons expressing diverse NS4B genes from corresponding subtypes of clinical isolates replicated at highly efficient levels for phenotypic analysis. Due to natural variation in their amino acid residues in NS4B, these isolates displayed varying drug susceptibilities to an NS4B inhibitor. In mixed populations with wild-type, the sensitivity of resistance detection of NS4B resistant mutants H94R and V105M was between 20% and 80%. The chimeric shuttle vectors can be used to characterize the activity of antiviral drugs targeting NS4B from diverse natural clinical isolates and aid in the development of novel compounds against HCV NS4B.

  15. Expression of human inducible nitric oxide synthase in a tetrahydrobiopterin (H4B)-deficient cell line: H4B promotes assembly of enzyme subunits into an active dimer.

    PubMed Central

    Tzeng, E; Billiar, T R; Robbins, P D; Loftus, M; Stuehr, D J

    1995-01-01

    Murine inducible nitric oxide (NO) synthase (iNOS) is catalytically active only in dimeric form. Assembly of its purified subunits into a dimer requires H4B. To understand the structure-activity relationships of human iNOS, we constitutively expressed recombinant human iNOS in NIH 3T3 cells by using a retroviral vector. These cells are deficient in de novo H4B biosynthesis and the role of H4B in the expression and assembly of active iNOS in an intact cell system could be studied. In the absence of added H4B, NO synthesis by the cells was minimal, whereas cells grown with supplemental H4B or the H4B precursor sepiapterin generated NO (74.1 and 63.3 nmol of nitrite per 10(6) cells per 24 h, respectively). NO synthesis correlated with an increase in intracellular H4B but no increase in iNOS protein. Instead, an increased percentage of dimeric iNOS was observed, rising from 20% in cytosols from unsupplemented cells to 66% in H4B-supplemented cell cytosols. In all cases, only dimeric iNOS displayed catalytic activity. Cytosols prepared from H4B-deficient cells exhibited little iNOS activity but acquired activity during a 60- to 120-min incubation with H4B, reaching final activities of 60-72 pmol of citrulline per mg of protein per min. Reconstitution of cytosolic NO synthesis activity was associated with conversion of monomers into dimeric iNOS during the incubation. Thus, human iNOS subunits dimerize to form an active enzyme, and H4B plays a critical role in promoting dimerization in intact cells. This reveals a post-translational mechanism by which intracellular H4B can regulate iNOS expression. Images Fig. 1 Fig. 3 Fig. 4 Fig. 5 PMID:8524846

  16. Optical and Near-UV Observations of the Transiting Extrasolar Planet TrES-4b

    NASA Astrophysics Data System (ADS)

    Smith, Carter-Thaxton; Turner, J.; Carleton, T.; Crawford, B.; Guvenen, B.; Hardegree-Ullman, K.; Small, L.; Towner, A. P.; Walker-LaFollette, A.; Henz, T.

    2013-01-01

    Using the Steward Observatory 61” Kuiper Telescope, The University of Arizona Astronomy Club conducted photometric observations of the transiting extrasolar planet TrES-4b as part of the Exoplanet Observation Project. Observations were made in the Bessell U, Harris B, and Harris R filters. Initial observations were made in 2009, with follow up observations in 2011. Basic data reduction and photometry was done using IRAF and determination of transit parameters was done using Transit Analysis Package (TAP) and JKTEBOP transit modeling code. We present an updated planetary mass, radius, density, surface gravity, Safronov number, equilibrium temperature, orbital distance, and orbital inclination for TrES-4b. In addition, we also searched for asymmetries between the near-UV and optical light curves. This project, started in spring 2009, has introduced many undergraduate students to research and given them valuable experience with data reduction and observation techniques.

  17. Qatar Exoplanet Survey : Qatar-3b, Qatar-4b, and Qatar-5b

    NASA Astrophysics Data System (ADS)

    Alsubai, Khalid; Mislis, Dimitris; Tsvetanov, Zlatan I.; Latham, David W.; Bieryla, Allyson; Buchhave, Lars A.; Esquerdo, Gilbert A.; Bramich, D. M.; Pyrzas, Stylianos; Vilchez, Nicolas P. E.; Mancini, Luigi; Southworth, John; Evans, Daniel F.; Henning, Thomas; Ciceri, Simona

    2017-04-01

    We report the discovery of Qatar-3b, Qatar-4b, and Qatar-5b, three new transiting planets identified by the Qatar Exoplanet Survey. The three planets belong to the hot Jupiter family, with orbital periods of {P}{{Q}3{{b}}} = 2.50792 days, {P}{{Q}4{{b}}} = 1.80539 days, and {P}{{Q}5{{b}}} = 2.87923 days. Follow-up spectroscopic observations reveal the masses of the planets to be {M}{{Q}3{{b}}} = 4.31 ± 0.47 {M}{{J}}, {M}{{Q}4{{b}}} = 6.10 ± 0.54 {M}{{J}}, and {M}{{Q}5{{b}}} = 4.32 ± 0.18 {M}{{J}}, while model fits to the transit light curves yield radii of {R}{{Q}3{{b}}} = 1.096 ± 0.14 {R}{{J}}, {R}{{Q}4{{b}}} = 1.135 ± 0.11 {R}{{J}}, and {R}{{Q}5{{b}}} = 1.107 ± 0.064 {R}{{J}}. The host stars are low-mass main sequence stars with masses and radii M Q3 = 1.145 ± 0.064 M ⊙, M Q4 = 0.896 ± 0.048 M ⊙, M Q5 = 1.128 ± 0.056 M ⊙ and R Q3 = 1.272 ± 0.14 R ⊙, R Q4 = 0.849 ± 0.063 R ⊙, and R Q5 = 1.076 ± 0.051 R ⊙ for Qatar-3, 4, and 5 respectively. The V magnitudes of the three host stars are V Q3 = 12.88, V Q4 = 13.60, and V Q5 = 12.82. All three new planets can be classified as heavy hot Jupiters (M > 4 M J).

  18. A Novel Benzodiazepine Compound Inhibits Yellow Fever Virus Infection by Specifically Targeting NS4B Protein.

    PubMed

    Guo, Fang; Wu, Shuo; Julander, Justin; Ma, Julia; Zhang, Xuexiang; Kulp, John; Cuconati, Andrea; Block, Timothy M; Du, Yanming; Guo, Ju-Tao; Chang, Jinhong

    2016-09-21

    Although a highly effective vaccine is available, the number of yellow fever cases has increased over the past two decades, which highlights the pressing need for antiviral therapeutics. In a high throughput screening campaign, we identified an acetic acid benzodiazepine (BDAA) compound, which potently inhibits yellow fever virus (YFV). Interestingly, while treatment of YFV infected cultures with 2 μM of BDAA reduced the virion production by greater than 2 logs, the compound is not active against 21 other viruses from 14 different viral families. Selection and genetic analysis of drug resistant viruses revealed that substitution of proline at amino acid 219 (P219) of the nonstructural protein 4B (NS4B) with serine, threonine or alanine confers YFV resistance to BDAA without apparent loss of replication fitness in cultured mammalian cells. However, substitution of P219 with glycine confers BDAA resistance with significant loss of replication ability. Bioinformatics analysis predicts that the P219 localizes at the endoplasmic reticulum lumen side of the fifth putative trans-membrane domain of NS4B and the mutation may render the viral protein incapable of interacting with BDAA. Our studies thus revealed important role and structural basis for NS4B protein in supporting YFV replication. Moreover, in YFV-infected hamsters, oral administration of BDAA protected 90% of the animals from death, significantly reduced viral load by greater than 2 logs and attenuated viral infection-induced liver injury and body weight loss. The encouraging preclinical results thus warrant further development of BDAA or its derivatives as antiviral agents to treat yellow fever.

  19. Molecular docking NS4B of DENV 1-4 with known bioactive phyto-chemicals

    PubMed Central

    Paul, Anubrata; Vibhuti, Arpana; Raj, Samuel

    2016-01-01

    Dengue disease is a global disease that has no effective treatment. The dengue virus (DENV) NS4B is a target for designing specific antivirals due to its importance in viral replication. Medicinal plants have been a savior for dengue virus as they consist of a class of phytochemicals having anti-viral activity and can pose a new approach ofstrong drug against viruses. The present study analyzes the activity of compounds against NS4B of DENV (1-4) serotypes. In this study Catechin, Cianidanol, Epicatechin, Eupatoretin, Glabranin, Laurifolin, DL-Catechin, astherapeutic agents were filtered by using Lipinski rule’s five and the drug-likeness property of these agents were used for assessment of pharmacological properties. The molecular docking results presented the 2-D structures of bioactive complex, which interacted with especially conserved residues of target domains. Interestingly, we find the Catechin, Laurifolin, Cianidanol have highest binding energy against NS4B in DENV-1,2,4 which is evident by the formation of more hydrogen bonds with the amino acid residues at the binding site of the receptor. Our results revealed that the bioactive compound, especially Catechin has significant anti-dengue activities. In addition, this study may be helpful in further experimental investigations. PMID:28149049

  20. DISTRIBUTION OF CH{sub 3}OH IN NGC 1333 IRAS4B

    SciTech Connect

    Sakai, Nami; Yamamoto, Satoshi; Ceccarelli, Cecilia; Bottinelli, Sandrine; Sakai, Takeshi

    2012-07-20

    Distribution of the CH{sub 3}OH (J{sub K} = 2{sub K}-1{sub K}, 96.7 GHz) emission has been investigated toward NGC 1333 IRAS4B, a low-mass Class 0 protostar which harbors a hot corino, with Nobeyama Millimeter Array. The CH{sub 3}OH emission is found to be prominent in the shocked region caused by an impact of the molecular outflow from the protostars. The direction of the outflow which is responsible for the shock seems to be opposite to that of a compact outflow known previously in the CO (J = 2-1), HCN (J = 1-0), H{sub 2}CO (3{sub 12}-2{sub 11}), and CH{sub 3}OH (J{sub K} = 7{sub K}-6{sub K}) emissions, whereas it is the same as that of the faint second outflow found in the H{sub 2}CO emission. This double outflow structure can be interpreted most naturally by the existence of more than two protostars in IRAS4B. On the other hand, a centrally condensed component associated apparently with IRAS4B cannot be recognized in our CH{sub 3}OH observation. Our observation suggests that, in this source, the CH{sub 3}OH (J{sub K} 2{sub K}-1{sub K}) emission preferentially traces the shocked regions rather than the hot corino around the protostar.

  1. HATS-4b: A dense hot Jupiter transiting a super metal-rich G star

    SciTech Connect

    Jordán, Andrés; Brahm, Rafael; Rabus, M.; Suc, V.; Espinoza, N.; Bakos, G. Á.; Penev, K.; Hartman, J. D.; Csubry, Z.; Bhatti, W.; De Val Borro, M.; Bayliss, D.; Zhou, G.; Mancini, L.; Mohler-Fischer, M.; Ciceri, S.; Csák, B.; Henning, T.; Sato, B.; Buchhave, L.; and others

    2014-08-01

    We report the discovery by the HATSouth survey of HATS-4b, an extrasolar planet transiting a V = 13.46 mag G star. HATS-4b has a period of P ≈ 2.5167 days, mass of M{sub p} ≈ 1.32 M {sub Jup}, radius of R{sub p} ≈ 1.02 R {sub Jup}, and density of ρ {sub p} = 1.55 ± 0.16 g cm{sup –3} ≈1.24 ρ{sub Jup}. The host star has a mass of 1.00 M {sub ☉}, a radius of 0.92 R {sub ☉}, and a very high metallicity [Fe/H]=0.43 ± 0.08. HATS-4b is among the densest known planets with masses between 1 and 2 M {sub J} and is thus likely to have a significant content of heavy elements of the order of 75 M {sub ⊕}. In this paper we present the data reduction, radial velocity measurements, and stellar classification techniques adopted by the HATSouth survey for the CORALIE spectrograph. We also detail a technique for simultaneously estimating vsin i and macroturbulence using high resolution spectra.

  2. Inhibition of HCV replication by humanized-single domain transbodies to NS4B.

    PubMed

    Glab-Ampai, Kittirat; Malik, Aijaz Ahmad; Chulanetra, Monrat; Thanongsaksrikul, Jeeraphong; Thueng-In, Kanyarat; Srimanote, Potjanee; Tongtawe, Pongsri; Chaicumpa, Wanpen

    2016-08-05

    NS4B of hepatitis C virus (HCV) initiates membrane web formation, binds RNA and other HCV proteins for viral replication complex (RC) formation, hydrolyses NTP, and inhibits innate anti-viral immunity. Thus, NS4B is an attractive target of a novel anti-HCV agent. In this study, humanized-nanobodies (VHs/VHHs) that bound to recombinant NS4B were produced by means of phage display technology. The nanobodies were linked molecularly to a cell penetrating peptide, penetratin (PEN), for making them cell penetrable (become transbodies). Human hepatic (Huh7) cells transfected with HCV JFH1-RNA that were treated with transbodies from four Escherichia coli clones (PEN-VHH7, PEN-VHH9, PEN-VH33, and PEN-VH43) had significant reduction of HCV RNA amounts in their culture fluids and intracellularly when compared to the transfected cells treated with control transbody and medium alone. The results were supported by the HCV foci assay. The transbody treated-transfected cells also had upregulation of the studied innate cytokine genes, IRF3, IFNβ and IL-28b. The transbodies have high potential for testing further as a novel anti-HCV agent, either alone, adjunct of existing anti-HCV agents/remedies, or in combination with their cognates specific to other HCV enzymes/proteins.

  3. Oscillations control of a transmission belt by Excitation Clipping using Clutch Clamping Control (E4C)

    NASA Astrophysics Data System (ADS)

    Temporelli, Robin; Micheau, Philippe

    2017-04-01

    A transmission belt deals with non-linear phenomena such as parametric excitations that can bring the belt in an instability region resulting in large transverse oscillations. These oscillations can cause belt life deflection, noise and unexpected vibration on its environment. The present study proposes a new strategy to control oscillations of a transmission belt subject to periodic tension fluctuations. Indeed, for a transmission belt, periodic torque fluctuations cause periodic belt tension fluctuations which can be a source of excitation for the belt and resulting in belt oscillations under certain conditions. The presence of a clutch between the belt end-point and the source of torque fluctuations offers a means to clip torque fluctuations and thus to clip belt excitation. In keeping with this notion, belt oscillations can be controlled by an Excitation Clipping using Clutch Clamping Control (E4C) strategy. Through an example of a transmission belt subject to periodic tension fluctuations, the E4C strategy is presented and a new analytical model of belt behavior with its E4C strategy is constructed. Free belt oscillations (E4C is not activated) and controlled belt oscillations (E4C is activated) are observed through an experimental setup and predicted owing to the new analytical model. Finally, the E4C strategy leads to frequency unlocking that successfully removes belt oscillations. This new analytical model furthermore provides an accurate prediction of belt behavior with its E4C strategy.

  4. (4R,4aS,4bS,7R,10aR)-4-Hy­droxy-4a,7-dimethyl-2-(propan-2-yl)-1,4,4a,4b,5,6,7,8,10,10a-deca­hydro­phenanthren-1-one

    PubMed Central

    Caracelli, Ignez; Zukerman-Schpector, Julio; Machado, André T. Lousada; Brocksom, Timothy J.; Ferreira, M. Lúcia; Tiekink, Edward R. T.

    2011-01-01

    In the title compound, C19H28O2, the A ring adopts a chair conformation, and each of the B and C rings adopts a distorted half-chair conformation with the methine C atom in the CH2C(H)C(=O) residue, common to both rings, lying 0.6397 (19) and 0.6328 (18) Å out of the approximate plane defined by the remaining five C atoms (r.m.s. deviations = 0.0791 and 0.0901 Å for rings B and C, respectively). Helical supra­molecular chains along the a axis mediated by hy­droxy–carbonyl O—H⋯O hydrogen bonds feature in the crystal packing. PMID:22220138

  5. (4R*,4aS*,4bS*,5R*,10aR*)-4-Hy­droxy-4a,5-dimethyl-2-(propan-2-yl)-1,4,4a,4b,5,6,7,8,10,10a-deca­hydro­phenan­thren-1-one

    PubMed Central

    Caracelli, Ignez; Zukerman-Schpector, Julio; Machado, André T. Lousada; Brocksom, Timothy J.; Ferreira, M. Lúcia; Tiekink, Edward R. T.

    2011-01-01

    In the title compound, C19H28O2, the A ring adopts a chair conformation. Both the B and C rings adopt envelope conformations with the C atoms common to both rings and adjacent to the carbonyl and hydroxyl groups, respectively, lying 0.604 (3) and 0.634 (3) Å out of the mean planes defined by the remaining five C atoms of rings B and C, respectively (r.m.s. deviations = 0.0100 and 0.0157 Å, respectively). The formation of linear supra­molecular C(7) chains along the a axis mediated by hy­droxy-O—H⋯O(carbon­yl) hydrogen bonds is the most prominent feature of the crystal packing. PMID:22199834

  6. Structure-based affinity maturation of a chimeric anti-ricin antibody C4C13.

    PubMed

    Luo, Longlong; Luo, Qun; Guo, Leiming; Lv, Ming; Lin, Zhou; Geng, Jing; Li, Xinying; Li, Yan; Shen, Beifen; Qiao, Chunxia; Feng, Jiannan

    2014-01-01

    Ricin is a highly lethal toxin. Anti-ricin chimeric monoclonal antibody (mAb) C4C13 was prepared in our lab; however, its binding affinity was much weaker than that of the parent antibody 4C13. In this study, based on the computer-guided homology modeling and conformational optimization methods, the 3-D structure of C4C13 variable regions Fv was constructed and optimized. Using molecular docking and dynamics simulation methods, the 3-D complex structure of ricin and C4C13 Fv was obtained. Considering the orientation property, surface electrostatic distribution, residues chemical and physical character and intermolecular hydrogen bond, the binding mode and key residues were predicted. According to C4C13 Fv fragment and ricin complementary binding surface, electrostatic attraction periphery and van der Waals interaction interface, three mutants (i.e., M1 (N(H102)F, W(H103)Y); M2 (W(H103)Y) and M3 (R(L90)G)) were designed, in which M1 and M2 were predicted to possess higher antigen-binding activity than C4C13, while M3 was weaker. The relative affinity assays by ELISA showed that M1 and M2 mutations had higher affinity (9.6 and 18.3 nmol/L) than C4C13 (130 nmol/L) and M3 had weaker affinity (234.5 nmol/L) than C4C13. The results showed that the modeling complex structure of the antigen (ricin) and antibody (C4C13) is reasonable. Our work offered affinity maturated antibodies by site mutations, which were beneficial for valuable anti-ricin antibody design and preparation in future.

  7. Vacuolar protein sorting 4B regulates apoptosis of intestinal epithelial cells via p38 MAPK in Crohn's disease.

    PubMed

    Zhang, Dongmei; Wang, Liang; Yan, Lijun; Miao, Xianjing; Gong, Chen; Xiao, Min; Ni, Runzhou; Tang, Qiyun

    2015-02-01

    Vacuolar protein sorting 4B (VPS4B), a member of ATPase family proteins, reportedly possesses multiple biological functions, such as regulating the development of breast cancer and non-small-cell lung cancer, participating in Parkinson's disease, and modulating neuronal apoptosis after cerebral ischemia. However, its expression and potential functions in Crohn's disease (CD) has not been understood. In this study, we reported for the first time that VPS4B was over-expressed in intestinal epithelial cell (IECs) of patients with CD. In TNBS-induced mouse colitis models, we observed the up-regulation of VPS4B was accompanied with the elevated levels of IEC apoptotic markers (active caspase-3 and cleaved PARP) and phosphorylated p38 in colitis IECs. Co-localization of VPS4B and active caspase-3 in IECs of the TNBS group further indicated the possible involvement of VPS4B in IEC apoptosis. Employing the TNF-α-treated HT29 cells as an in vitro IEC apoptosis model, we confirmed the positive correlation of VPS4B with caspase-dependent cellular apoptosis. Knocking VPS4B down by siRNA significantly alleviated TNF-α-induced p38 phosphorylation and cellular apoptosis in HT29 cells. Taken together, our findings suggested that VPS4B may facilitate the IEC apoptosis in CD via p38 MAPK signaling pathway.

  8. w4CSeq: software and web application to analyze 4C-seq data.

    PubMed

    Cai, Mingyang; Gao, Fan; Lu, Wange; Wang, Kai

    2016-11-01

    Circularized Chromosome Conformation Capture followed by deep sequencing (4C-Seq) is a powerful technique to identify genome-wide partners interacting with a pre-specified genomic locus. Here, we present a computational and statistical approach to analyze 4C-Seq data generated from both enzyme digestion and sonication fragmentation-based methods. We implemented a command line software tool and a web interface called w4CSeq, which takes in the raw 4C sequencing data (FASTQ files) as input, performs automated statistical analysis and presents results in a user-friendly manner. Besides providing users with the list of candidate interacting sites/regions, w4CSeq generates figures showing genome-wide distribution of interacting regions, and sketches the enrichment of key features such as TSSs, TTSs, CpG sites and DNA replication timing around 4C sites.

  9. KDM4C Activity Modulates Cell Proliferation and Chromosome Segregation in Triple-Negative Breast Cancer

    PubMed Central

    Garcia, Jeison; Lizcano, Fernando

    2016-01-01

    The Jumonji-containing domain protein, KDM4C, is a histone demethylase associated with the development of several forms of human cancer. However, its specific function in the viability of tumoral lineages is yet to be determined. This work investigates the importance of KDM4C activity in cell proliferation and chromosome segregation of three triple-negative breast cancer cell lines using a specific demethylase inhibitor. Immunofluorescence assays show that KDM4C is recruited to mitotic chromosomes and that the modulation of its activity increases the number of mitotic segregation errors. However, 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) cell proliferation assays demonstrate that the demethylase activity is required for cell viability. These results suggest that the histone demethylase activity of KDM4C is essential for breast cancer progression given its role in the maintenance of chromosomal stability and cell growth, thus highlighting it as a potential therapeutic target. PMID:27840577

  10. Microstructure and Tensile Behaviour of B4C Reinforced ZA43 Alloy Composites

    NASA Astrophysics Data System (ADS)

    Adaveesh, B.; Halesh, G. M.; Nagaral, Madeva; Mohan Kumar, T. S.

    2016-09-01

    The work is carried out to investigate and study the mechanical properties of B4C reinforced ZA43 alloy metal matrix composites. In the present work ZA43 alloy is taken as the base matrix and B4C particulates as reinforcement material to prepare metal matrix composites by stir casting method. For metal matrix composites the reinforcement material was varied from 0 to 6 wt.% in steps of 3 wt.%. For each composite, the reinforcement particulates were preheated to a temperature of 300°C and dispersed into a vortex of molten ZA43 alloy. The microstructural characterization was done using scanning electron microscope. Mechanical properties like hardness, ultimate tensile strength and yield strength were evaluated as per ASTM standards. Further, scanning electron microphotographs revealed that there was uniform distribution of B4C particulates in ZA43 alloy matrix. Hardness, ultimate tensile strength and yield strength increased as wt.% of B4C increased in the base matrix.

  11. INPP4B is upregulated and functions as an oncogenic driver through SGK3 in a subset of melanomas

    PubMed Central

    Wilmott, James S.; Guo, Xiang Yun; Yan, Xu Guang; Wang, Chun Yan; Liu, Xiao Ying; Jin, Lei; Tseng, Hsin-Yi; Liu, Tao; Croft, Amanda; Hondermarck, Hubert; Scolyer, Richard A.; Jiang, Chen Chen; Zhang, Xu Dong

    2015-01-01

    Inositol polyphosphate 4-phosphatase type II (INPP4B) negatively regulates PI3K/Akt signalling and has a tumour suppressive role in some types of cancers. However, we have found that it is upregulated in a subset of melanomas. Here we report that INPP4B can function as an oncogenic driver through activation of serum- and glucocorticoid-regulated kinase 3 (SGK3) in melanoma. While INPP4B knockdown inhibited melanoma cell proliferation and retarded melanoma xenograft growth, overexpression of INPP4B enhanced melanoma cell and melanocyte proliferation and triggered anchorage-independent growth of melanocytes. Noticeably, INPP4B-mediated melanoma cell proliferation was not related to activation of Akt, but was mediated by SGK3. Upregulation of INPP4B in melanoma cells was associated with loss of miRNA (miR)-494 and/or miR-599 due to gene copy number reduction. Indeed, overexpression of miR-494 or miR-599 downregulated INPP4B, reduced SGK3 activation, and inhibited melanoma cell proliferation, whereas introduction of anti-miR-494 or anti-miR-599 upregulated INPP4B, enhanced SGK3 activation, and promoted melanoma cell proliferation. Collectively, these results identify upregulation of INPP4B as an oncogenic mechanism through activation of SGK3 in a subset of melanomas, with implications for targeting INPP4B and restoring miR-494 and miR-599 as novel approaches in the treatment of melanomas with high INPP4B expression. PMID:26573229

  12. The Top 10 Things I LOVE about p4c Hawai'i

    ERIC Educational Resources Information Center

    Ikeda, Jolyn

    2012-01-01

    In 2001, Dr. Thomas Jackson, or Dr. J as the author and her colleagues affectionately call him, spoke to the faculty at Waikiki Elementary. He described philosophy for children (p4c) Hawai'i and encouraged them to try P4C if something about it "resonated" with them. In the beginning, Dr. J held a p4t (philosophy for teachers)…

  13. TL and OSL studies of carbon doped magnesium aluminate (MgAl2O4:C)

    NASA Astrophysics Data System (ADS)

    Raj, Sanu S.; Mishra, D. R.; Soni, Anuj; Grover, V.; Polymeris, G. S.; Muthe, K. P.; Jha, S. K.; Tyagi, A. K.

    2016-10-01

    The MgAl2O4:C has been synthesized by using two different methods by electron gun and vacuum assisted melting of MgAl2O4 in presence of graphite. The MgAl2O4:C phosphor thus developed by these two different methods have similar types of the TL/OSL defects with multiple overlapping TL glow peaks from 100 °C to 400 °C. The Computerized Curve De-convolution Analysis (CCDA) has been used to measure TL parameters such as thermal trap depth, frequency factor and order of kinetic associated with charge transfer process in TL phenomenon. The investigated TL/OSL results show that these two methods of incorporating carbon in MgAl2O4 have generated closely resemble the defects of similar types in MgAl2O4:C lattice. However, the MgAl2O4:C synthesized by electron gun shows relatively larger concentration of the TL/OSL defects as compared to MgAl2O4:C synthesized using vacuum assisted melting method. The photo-ionization cross-section (PIC) associated with fastest OSL component of MgAl2O4: C is found to be ∼ 0.5 times than that of fastest OSL component of commercially available dosimetric grade α-Al2O3:C. The MgAl2O4:C thus developed shows good dynamic OSL dose linearity from few mGy to 1 Gy. This work reveals that MgAl2O4:C could be developed as potential tissue equivalent OSL / TL material.

  14. The Cry4B toxin of Bacillus thuringiensis subsp. israelensis kills Permethrin-resistant Anopheles gambiae, the principal vector of malaria.

    PubMed

    Ibrahim, Mohamed A; Griko, Natalya B; Bulla, Lee A

    2013-04-01

    Resurgence of malaria has been attributed, in part, to the development of resistance by Anopheles gambiae, a principal vector of the disease, to various insecticidal compounds such as Permethrin. Permethrin, a neurotoxicant, is widely used to impregnate mosquito nets. An alternative strategy to control mosquitoes is the use of Bacillus thuringiensis subsp. israelensis (Bti) because there is no observable resistance in the field to the bacterium. Bti kills mosquitoes by targeting cadherin molecules residing in the midgut epithelium of larvae of the insect. Cry proteins (Cry4A, Cry4B, Cry10A and Cry11A) produced by the bacterium during the sporulation phase of its life cycle bind to the cadherin molecules, which serve as receptors for the proteins. These Cry proteins have variable specificity to a variety of mosquitoes, including Culex and Aedes as well as Anopheles. Importantly, selective mosquitocidal action is occasioned by binding of the respective Cry toxins to cadherins distinctive to individual mosquito species. Differential fractionation of the four Cry proteins from a novel Bti isolate (M1) and cloning and expression of their genes in Escherichia coli revealed that Cry4B is the only Cry protein that exerts insecticidal action against An. gambiae. Indeed, it does so against a Permethrin-resistant strain of the mosquito. The other three Cry proteins are ineffective. Multiple sequence alignments of the four Cry proteins revealed a divergent sequence motif in the Cry4B toxin, which most likely determines binding of the toxin to its cognate receptor, BT-R3, in An. gambiae and to its specific toxicity. A model showing Cry4B toxin binding to BT-R3 is presented.

  15. New AP4B1 mutation in an African-American child associated with intellectual disability.

    PubMed

    Lamichhane, Dronacharya

    2013-12-01

    Prevalence of intellectual disability (ID) varies from 1-3%. Genetic causes of ID are being increasingly recognized. Although multiple mutations have been identified as a cause of syndromic ID, the genetic etiology of non-syndromic ID is poorly understood. However, more than 100 loci have been mapped that are associated with non-syndromic ID. There have been a couple of reports of AP4B1 gene mutation causing severe intellectual disability, absent speech, shy character, stereotypic laughter, muscular hypotonia that progressed to spastic paraplegia, microcephaly, foot deformity, decreased muscle mass of the lower limbs, inability to walk, and growth retardation. They had structural brain abnormalities and seizures. The reported cases were from Arab families where consanguineous marriage is common. We encountered an African-American child who presented first at the age of 24 mo with language difficulties and was subsequently found to have moderate to severe intellectual disability by standardized tests. Shortly, he started to have seizures and problems with ambulation. Although he was hypotonic at the time of presentation, legs slowly became spastic at the age of 4 yr. After a thorough work up, he was found to have heterozygous mutation in the AP4B1 gene along with another missense mutation in the same gene. There has been no report of mutation in this gene in the North American population. Although AP4B1 typically is said to be an autosomal recessive disease-causing gene, our case is different in the sense that there are two mutations in the same gene one of which has never been reported before and co-exists with a known disease causing mutation. Yet, the phenotype of the case closely resembles those published previously.

  16. Yersiniosis due to infection by Yersinia pseudotuberculosis 4b in captive meerkats (Suricata suricatta) in Japan.

    PubMed

    Nakamura, Shin-Ichi; Hayashidani, Hideki; Yonezawa, Aya; Suzuki, Isao; Une, Yumi

    2015-09-01

    Two meerkats (Suricata suricatta) housed in the same zoological garden in Japan died due to Yersinia pseudotuberculosis serotype 4b infection. Gross and microscopic lesions included necrotizing enteritis and enlargement of the spleen and liver with multifocal necrosis. Inflammatory cells, primarily neutrophils, and nuclear debris were associated with clusters of Gram-negative bacilli. Additionally, there were aberrant organism forms that were larger than bacilli and appeared as basophilic globular bodies. Immunohistochemical examination showed that the bacilli and globular bodies were strongly positive for Y. pseudotuberculosis O4 antigen. The globular bodies were considered a shape-changed form of Y. pseudotuberculosis, and these morphologically abnormal bacteria could present a diagnostic challenge.

  17. Input files with ORNL—mathematical phantoms of the human body for MCNP-4B

    NASA Astrophysics Data System (ADS)

    Krstić, D.; Nikezić, D.

    2007-01-01

    Protection against ionizing radiation requires information on the absorbed doses in organs of the human body. Implantation of many dosimeters in the human body is undesirable (or impossible), so the doses in organs are not measurable and some kind of dose calculation has to be applied. Calculation of doses in organs requests: (a) an exact description of the geometry of organs, (b) the chemical constitution of tissues, and (c) appropriate computer programs. The first two items, (a) and (b), make a so-called "phantom". In another words, the "phantom of a human body" is a mathematical representation of the human body including all other relevant information. All organs are represented with geometrical bodies (like cylinders, ellipsoids, tori, cones etc.), which are described with suitable mathematical equations. A corresponding chemical constitution for various types of organ tissues is also defined. MCNP-4B ( Monte Carlo N- Particle) is often used as transport code. Users of this software prepare an "input file" providing all necessary information for program execution. This information includes: (a) source definition—type of ionizing radiation, energy spectrum, and geometry of the source; (b) target definition—material constitution, geometry, location in respect to the source etc.; (c) characterization of absorbing media between the source and target; (d) output tally, etc. This paper presents input files with "human phantoms" for the MCNP-4B code. The input files with "phantoms" were prepared based on publications issued by the Oak Ridge National Laboratory (ORNL). Seven input files relating to different age groups (newborn, 1, 5, 10, 15 years, as well as, male and female adults) are presented here. A test example and comparison with other data found in literature are also given. Program summaryTitle of program: INPUT FILES, AMALE, AFEMALE, AGE15, AGE10, AGE5, AGE01, NEWB Catalogue identifier:ADYF_v1_0 Program summary URL

  18. Synergistic interactions between PDE4B and GSK-3: DISC1 mutant mice.

    PubMed

    Lipina, Tatiana V; Wang, Min; Liu, Fang; Roder, John C

    2012-03-01

    Disrupted-In-Schizophrenia-1 (DISC1) is a strong genetic risk factor associated with psychiatric disorders. Two distinct mutations in the second exon of the DISC1 gene (Q31L and L100P) lead to either depression- or schizophrenia-like behavior in mice. Both phosphodiesterase-4B (PDE4B) and glycogen synthase kinase-3 (GSK-3) have common binding sites on N-terminal region of DISC1 and are implicated into etiology of schizophrenia and depression. It is not known if PDE4B and GSK-3 could converge signals in the cell via DISC1 at the same time. The purpose of the present study was to assess whether rolipram (PDE4 inhibitor) might synergize with TDZD-8 (GSK-3 blocker) to produce antipsychotic effects at low doses on the DISC1-L100P genetic model. Indeed, combined treatment of DISC1-L100P mice with rolipram (0.1 mg/kg) and TDZD-8 (2.5 mg/kg) in sub-threshold doses corrected their Pre-Pulse Inhibition (PPI) deficit and hyperactivity, without any side effects at these doses. We have suggested that rolipram-induced increase of cAMP level might influence GSK-3 function and, hence the efficacy of TDZD-8. Our second goal was to estimate how DISC1-Q31L with reduced PDE4B activity, and therefore mimicking rolipram-induced conditions, could alter pharmacological response to TDZD-8, GSK-3 activity and its interaction with DISC1. DISC1-Q31L mutants showed increased sensitivity to GSK-3 inhibitor compare to DISC1-L100P mice. TDZD-8 (2.5 mg/kg) was able to correct PPI deficit, reduce immobility in the forced swim test (FST) and increased social motivation/novelty. In parallel, biochemical analysis revealed significantly reduced binding of GSK-3 to the mutated DISC1-Q31L and increased enzymatic activity of GSK-3. Taken together, genetic variations in DISC1 influence formation of biochemical complex with PDE4 and GSK-3 and strength the possibility of synergistic interactions between these proteins.

  19. Crystal structure features in a new compound C4B25Mg1.42

    NASA Astrophysics Data System (ADS)

    Konovalikhin, S. V.; Ponomarev, V. I.

    2015-09-01

    The composition of C4B25Mg1.42 crystal obtained by self-propagating high-temperature synthesis was determined using X-ray diffraction. This is the first crystalline structure where all boron atoms in the В12 icosahedron occupy crystallographically independent positions; this circumstance allowed us to analyze the effect of substituents on bond lengths in the icosahedron. The crystal structure features, including the channels filled with disordered Mg atoms and the spread of В—В endo- and exo-bond lengths in the icosahedra, are described. A crystallochemical analysis of pair bonds has been performed for the first time.

  20. Complete Genome Sequence of the Larvicidal Bacterium Lysinibacillus sphaericus Strain OT4b.25

    PubMed Central

    Rey, Andrés; Silva-Quintero, Laura

    2016-01-01

    Lysinibacillus sphaericus OT4b.25 is a native Colombian strain isolated from coleopteran larvae in an oak forest near Bogotá D.C.; this strain has shown high levels of pathogenic activity against Culex quinquefasciatus larvae in laboratory assays compared to that of other members of the same species. Using Pacific Biosciences sequencing technology, we propose a chromosomal contig of 4,665,775 bp that, according to comparative analysis, is highly similar to that of reference strain L. sphaericus C3-41. PMID:27151786

  1. Population Structure of Listeria monocytogenes Serotype 4b Isolates from Sporadic Human Listeriosis in the United States, 2003-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Listeria monocytogenes can cause severe foodborne disease (listeriosis). Serotype 4b strains have resulted in numerous outbreaks, repeatedly involving three epidemic clones (ECI, ECII, and ECIa). Little is known about population structure of L. monocytogenes serotype 4b from sporadic listeriosis, ev...

  2. 75 FR 41871 - International Conference on Harmonisation; Draft Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-19

    ... Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... availability of a draft guidance entitled ``Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use... evaluation of the Bacterial Endotoxins Test General Chapter harmonized text from each of the...

  3. Identification of Amino Acid Determinants in CYP4B1 for Optimal Catalytic Processing of 4-Ipomeanol

    PubMed Central

    Wiek, Constanze; Schmidt, Eva M; Roellecke, Katharina; Freund, Marcel; Nakano, Mariko; Kelly, Edward J; Kaisers, Wolfgang; Yarov-Yarovoy, Vladimir; Kramm, Christof M; Rettie, Allan E; Hanenberg, Helmut

    2014-01-01

    Mammalian CYP4B1 enzymes are cytochrome P450 monooxygenases that are responsible for the bioactivation of several exogenous pro-toxins including 4-ipomeanol (4-IPO). In contrast to the orthologous rabbit enzyme, we show here that native human CYP4B1 with a serine at position 427 is unable to bio-activate 4-IPO and does not cause cytotoxicity in HepG2 cells and primary human T-cells that overexpress these enzymes. We also demonstrate that a proline residue in the meander region at position 427 in human CYB4B1 and 422 in rabbit CYP4B1 is important for protein stability and rescues the 4-IPO bioactivation of the human enzyme, but is not essential for the catalytic activity of the rabbit CYP4B1 protein. Systematic substitution of native and p.S427P human CYP4B1 with peptide regions from the highly active rabbit enzyme reveals that 18 amino acids in the wild-type rabbit CYP4B1 protein are key for conferring high 4-IPO metabolizing activity. Introduction of 12 of the 18 amino acids that are also present at corresponding positions in other human CYP4 family members into the p.S427P human CYP4B1 protein results in a mutant human enzyme (P+12) that is as stable and as active as the rabbit wild-type CYP4B1 protein. These 12 mutations cluster in the predicted B–C loop through F-helix regions and reveal new amino acid regions important to P450 enzyme stability. Finally, by minimally re-engineering the human CYP4B1 enzyme for efficient activation of 4-IPO, we have developed a novel human suicide gene system that is a candidate for adoptive cellular therapies in humans. PMID:25247810

  4. The plasma membrane Ca(2+) pump PMCA4b inhibits the migratory and metastatic activity of BRAF mutant melanoma cells.

    PubMed

    Hegedũs, Luca; Garay, Tamás; Molnár, Eszter; Varga, Karolina; Bilecz, Ágnes; Török, Szilvia; Padányi, Rita; Pászty, Katalin; Wolf, Matthias; Grusch, Michael; Kállay, Enikõ; Döme, Balázs; Berger, Walter; Hegedũs, Balázs; Enyedi, Agnes

    2016-11-04

    Oncogenic mutations of BRAF lead to constitutive ERK activity that supports melanoma cell growth and survival. While Ca(2+) signaling is a well-known regulator of tumor progression, the crosstalk between Ca(2+) signaling and the Ras-BRAF-MEK-ERK pathway is much less explored. Here we show that in BRAF mutant melanoma cells the abundance of the plasma membrane Ca(2+) ATPase isoform 4b (PMCA4b, ATP2B4) is low at baseline but markedly elevated by treatment with the mutant BRAF specific inhibitor vemurafenib. In line with these findings gene expression microarray data also shows decreased PMCA4b expression in cutaneous melanoma when compared to benign nevi. The MEK inhibitor selumetinib-similarly to that of the BRAF-specific inhibitor-also increases PMCA4b levels in both BRAF and NRAS mutant melanoma cells suggesting that the MAPK pathway is involved in the regulation of PMCA4b expression. The increased abundance of PMCA4b in the plasma membrane enhances [Ca(2+) ]i clearance from cells after Ca(2+) entry. Moreover we show that both vemurafenib treatment and PMCA4b overexpression induce marked inhibition of migration of BRAF mutant melanoma cells. Importantly, reduced migration of PMCA4b expressing BRAF mutant cells is associated with a marked decrease in their metastatic potential in vivo. Taken together, our data reveal an important crosstalk between Ca(2+) signaling and the MAPK pathway through the regulation of PMCA4b expression and suggest that PMCA4b is a previously unrecognized metastasis suppressor.

  5. LARP4B is an AU-rich sequence associated factor that promotes mRNA accumulation and translation.

    PubMed

    Küspert, Maritta; Murakawa, Yasuhiro; Schäffler, Katrin; Vanselow, Jens T; Wolf, Elmar; Juranek, Stefan; Schlosser, Andreas; Landthaler, Markus; Fischer, Utz

    2015-07-01

    mRNAs are key molecules in gene expression and subject to diverse regulatory events. Regulation is accomplished by distinct sets of trans-acting factors that interact with mRNAs and form defined mRNA-protein complexes (mRNPs). The resulting "mRNP code" determines the fate of any given mRNA and thus controlling gene expression at the post-transcriptional level. The La-related protein 4B (LARP4B) belongs to an evolutionarily conserved family of RNA-binding proteins characterized by the presence of a La-module implicated in direct RNA binding. Biochemical experiments have shown previously direct interactions of LARP4B with factors of the translation machinery. This finding along with the observation of an association with actively translating ribosomes suggested that LARP4B is a factor contributing to the mRNP code. To gain insight into the function of LARP4B in vivo we tested its mRNA association at the transcriptome level and its impact on the proteome. PAR-CLIP analyses allowed us to identify the in vivo RNA targets of LARP4B. We show that LARP4B binds to a distinct set of cellular mRNAs by contacting their 3' UTRs. Biocomputational analysis combined with in vitro binding assays identified the LARP4B-binding motif on mRNA targets. The reduction of cellular LARP4B levels leads to a marked destabilization of its mRNA targets and consequently their reduced translation. Our data identify LARP4B as a component of the mRNP code that influences the expression of its mRNA targets by affecting their stability.

  6. Expression and localization of rat NBC4c in liver and renal uroepithelium.

    PubMed

    Abuladze, Natalia; Pushkin, Alexander; Tatishchev, Sergei; Newman, Debra; Sassani, Pakan; Kurtz, Ira

    2004-09-01

    Previous studies provided functional evidence for electrogenic Na(+)-HCO(3)(-) cotransport in hepatocytes and in intrahepatic bile duct cholangiocytes. The molecular identity of the transporters mediating electrogenic sodium-bicarbonate cotransport in the liver is currently unknown. Of the known electrogenic Na(+)-HCO(3)(-) cotransporters (NBC1 and NBC4), we previously showed that NBC4 mRNA is highly expressed in the liver. In the present study, we performed RT-PCR, immunoblotting, and immunohistochemistry to characterize the expression pattern of NBC4 in rat liver and kidney. For immunodetection, a polyclonal antibody against rat NBC4 was generated and affinity purified. Of the known human NBC4 variants, only the rat NBC4c ortholog was detected by RT-PCR in rat liver, and the molecular mass of the NBC4c protein was approximately 145 kDa. NBC4c protein was expressed in hepatocytes and in the cholangiocytes lining the intrahepatic bile ducts. In hepatocytes, NBC4c was localized to the basolateral plasma membrane, whereas intrahepatic cholangiocytes stained apically. The NBC1 electrogenic sodium cotransporter variants kNBC1 and pNBC1 were not detected by immunoblotting and immunohistochemistry in rat liver. The pattern of localization of NBC4c in the liver suggests that the cotransporter plays a role in mediating Na(+)-HCO(3)(-) cotransport in hepatocytes and intrahepatic cholangiocytes. Unlike the liver, the rat kidney expressed electrogenic sodium-bicarbonate cotransporter proteins kNBC1 and NBC4c. In kidney, NBC4c also had a molecular mass of approximately 145 kDa and was immunolocalized to uroepithelial cells lining the renal pelvis, where the cotransporter may play an important role in protecting the renal parenchyma from alterations in urine pH.

  7. The electron and energy transfer between oligothiophenes and thieno[3,4-b]thiophene units

    NASA Astrophysics Data System (ADS)

    Szarko, Jodi; Guo, Jianchang; Liang, Yongye; Rolczynski, Brian; Yu, Luping; Chen, Lin X.

    2008-08-01

    In a recent study, it has been shown that organic photovoltaic (OPV) solar cells consisting of polymers with certain stoichiometric ratios of alkyl thiophene:thieno[3,4-b]thiophene monomeric units in random sequences, when combined with [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), may have potentials for creating more efficient devices. Such a potential enhancement is mainly due to the light harvesting in most of the visible and near infrared region by these low band-gap polymers. However, very little is known about the photoinduced energy/electron transfer and transport within these copolymers. It is important to understand both the ultrafast interactions between these two monomeric units when they are linked in the copolymers and their interactions with the electron acceptor PCBM in order to determine the transport mechanisms in these systems, and then to create the architectures that optimize electronic transport properties. Therefore, three oligomer molecules have been synthesized to model the local interactions in the copolymers, each of which consists of a thieno[3,4-b] thiophene derivative at its center linked with two alkyl oligothiophene side units. The alkyl oligothiophene units for the three molecules are 2, 4, or 8 units in length. By performing transient absorption and fluorescence upconversion measurements, the nature of the early exciton diffusion and energy transfer between these different units is elucidated.

  8. Geopotential Model Improvement Using POCM_4B Dynamic Ocean Topography Information: PGM2000A

    NASA Technical Reports Server (NTRS)

    Pavlis, N. K.; Chinn, D. S.; Cox, C. M.; Lemoine, Frank G.; Smith, David E. (Technical Monitor)

    2000-01-01

    The two-year mean (1993-1994) Dynamic Ocean Topography (DOT) field implied by the POCM_4B circulation model was used to develop normal equations for DOT, in a surface spherical harmonic representation. These normal equations were combined with normal equations from satellite tracking data, surface gravity data, and altimeter data from TOPEX/Poseidon and ERS-1. Several least-squares combination solutions were developed in this fashion, by varying parameters such as the maximum degree of the estimated DOT and the relative weights of the different data. The solutions were evaluated in terms of orbit fit residuals, GPS/Leveling-derived undulations, and independent DOT information from in situ WOCE hydrographic data. An optimal solution was developed in this fashion which was originally presented at the 1998 EGS meeting in Nice, France. This model, designated here PGM2000A, maintains the orbit and land geoid modeling performance of EGM96, while improving its marine geoid modeling capability. In addition, PGM2000A's error spectrum is considerably more realistic than those of other contemporary gravitational models and agrees well with the error spectrum of EGM96. We will present the development and evaluation of PGM2000A, with particular emphasis on the weighting of the DOT information implied by POCM_4B. We will also present an inter-comparison of PGM2000A with the GRIM5-C1 and TEG-4 models. Directions for future work and problematic areas will be identified.

  9. Prolactin Regulatory Element Binding Protein Is Involved in Hepatitis C Virus Replication by Interaction with NS4B

    PubMed Central

    Kong, Lingbao; Fujimoto, Akira; Nakamura, Mariko; Aoyagi, Haruyo; Matsuda, Mami; Watashi, Koichi; Suzuki, Ryosuke; Arita, Minetaro; Yamagoe, Satoshi; Dohmae, Naoshi; Suzuki, Takehiro; Sakamaki, Yuriko; Ichinose, Shizuko; Suzuki, Tetsuro; Wakita, Takaji

    2016-01-01

    ABSTRACT It has been proposed that the hepatitis C virus (HCV) NS4B protein triggers the membranous HCV replication compartment, but the underlying molecular mechanism is not fully understood. Here, we screened for NS4B-associated membrane proteins by tandem affinity purification and proteome analysis and identified 202 host proteins. Subsequent screening of replicon cells with small interfering RNA identified prolactin regulatory element binding (PREB) to be a novel HCV host cofactor. The interaction between PREB and NS4B was confirmed by immunoprecipitation, immunofluorescence, and proximity ligation assays. PREB colocalized with double-stranded RNA and the newly synthesized HCV RNA labeled with bromouridine triphosphate in HCV replicon cells. Furthermore, PREB shifted to detergent-resistant membranes (DRMs), where HCV replication complexes reside, in the presence of NS4B expression in Huh7 cells. However, a PREB mutant lacking the NS4B-binding region (PREBd3) could not colocalize with double-stranded RNA and did not shift to the DRM in the presence of NS4B. These results indicate that PREB locates at the HCV replication complex by interacting with NS4B. PREB silencing inhibited the formation of the membranous HCV replication compartment and increased the protease and nuclease sensitivity of HCV replicase proteins and RNA in DRMs, respectively. Collectively, these data indicate that PREB promotes HCV RNA replication by participating in the formation of the membranous replication compartment and by maintaining its proper structure by interacting with NS4B. Furthermore, PREB was induced by HCV infection in vitro and in vivo. Our findings provide new insights into HCV host cofactors. IMPORTANCE The hepatitis C virus (HCV) protein NS4B can induce alteration of the endoplasmic reticulum and the formation of a membranous web structure, which provides a platform for the HCV replication complex. The molecular mechanism by which NS4B induces the membranous HCV replication

  10. Hot Deformation and Processing Maps of Al-15%B4C Composites Containing Sc and Zr

    NASA Astrophysics Data System (ADS)

    Qin, Jian; Zhang, Zhan; Chen, X.-Grant

    2017-03-01

    Hot deformation behavior and processing maps of three Al-15%B4C composites denoted as the base composite (Al-15vol.%B4C), S40 (Al-15vol.%B4C-0.4wt.%Sc) and SZ40 (Al-15 vol.%B4C-0.4wt.%Sc-0.24wt.%Zr) were studied by uniaxial compression tests performed at various deformation temperatures and strain rates. The constitutive equations of the three composites were established to describe the effect of the temperature and strain rate on hot deformation behavior. Using the established constitutive equations, the predicted flow stresses on various deformation conditions agreed well with the experimental data. The peak flow stress of the composites increased with the addition of Sc and Zr, attributing to the synthetic effect of solute atoms and dynamic precipitation. The addition of Sc and Zr increased the activation energy for hot deformation of Al-B4C composites. The processing maps of the three composites were constructed to evaluate the hot workability of the composites. The safe domains with optimal deformation conditions were identified for all three composites. In the safe domains, dynamic recovery and dynamic recrystallization were involved as softening mechanisms. The addition of Sc and Zr limited the dynamic softening process, especially for dynamic recrystallization. The microstructure analysis revealed that the flow instability was attributed to the void formation, cracking and flow localization during hot deformation of the composites.

  11. Interfacial microstructure in a B{sub 4}C/Al composite fabricated by pressureless infiltration.

    SciTech Connect

    Luo, Z.; Song, Y.; Zhang, S.; Miller, D. J.

    2012-01-01

    In this work, B{sub 4}C particulate-reinforced Al composite was fabricated by a pressureless infiltration technique, and its interfacial microstructure was studied in detail by X-ray diffraction as well as by scanning and transmission electron microscopy. The B{sub 4}C phase was unstable in Al melt during the infiltration process, forming AlB{sub 10}-type AlB{sub 24}C{sub 4} or Al{sub 2.1}B{sub 51}C{sub 8} as a major reactant phase. The Al matrix was large grains (over 10 {micro}m), which had no definite orientation relationships (ORs) with the randomly orientated B{sub 4}C or its reactant particles, except for possible nucleation sites with {l_brace}011{r_brace}{sub B{sub 4}C} almost parallel to {l_brace}111{r_brace}{sub Al} at a deviation angle of 1.5 deg. Both B{sub 4}C-Al and reactant-Al interfaces are semicoherent and free of other phases. A comparison was made with the SiC/Al composite fabricated similarly by the pressureless infiltration. It was suggested that the lack of ORs between the Al matrix and reinforced particles, except for possible nucleation sites, is the common feature of the composites prepared by the infiltration method.

  12. Mitochondrial haplogroup C4c: a rare lineage entering America through the ice-free corridor?

    PubMed

    Hooshiar Kashani, Baharak; Perego, Ugo A; Olivieri, Anna; Angerhofer, Norman; Gandini, Francesca; Carossa, Valeria; Lancioni, Hovirag; Semino, Ornella; Woodward, Scott R; Achilli, Alessandro; Torroni, Antonio

    2012-01-01

    Recent analyses of mitochondrial genomes from Native Americans have brought the overall number of recognized maternal founding lineages from just four to a current count of 15. However, because of their relative low frequency, almost nothing is known for some of these lineages. This leaves a considerable void in understanding the events that led to the colonization of the Americas following the Last Glacial Maximum (LGM). In this study, we identified and completely sequenced 14 mitochondrial DNAs belonging to one extremely rare Native American lineage known as haplogroup C4c. Its age and geographical distribution raise the possibility that C4c marked the Paleo-Indian group(s) that entered North America from Beringia through the ice-free corridor between the Laurentide and Cordilleran ice sheets. The similarities in ages andgeographical distributions for C4c and the previously analyzed X2a lineage provide support to the scenario of a dual origin for Paleo-Indians. Taking into account that C4c is deeply rooted in the Asian portion of the mtDNA phylogeny and is indubitably of Asian origin, the finding that C4c and X2a are characterized by parallel genetic histories definitively dismisses the controversial hypothesis of an Atlantic glacial entry route into North America.

  13. Challenge of human Jurkat T-cells with the adenylate cyclase activator forskolin elicits major changes in cAMP phosphodiesterase (PDE) expression by up-regulating PDE3 and inducing PDE4D1 and PDE4D2 splice variants as well as down-regulating a novel PDE4A splice variant.

    PubMed Central

    Erdogan, S; Houslay, M D

    1997-01-01

    The cAMP phosphodiesterase (PDE) 3 and PDE4 isoforms provide the major cAMP-hydrolysing PDE activities in Jurkat T-cells, with additional contributions from the PDE1 and PDE2 isoforms. Challenge of cells with the adenylate cyclase activator forskolin led to a rapid, albeit transient, increase in PDE3 activity occurring over the first 45 min, followed by a sustained increase in PDE3 activity which began after approximately 3 h and continued for at least 24 h. Only this second phase of increase in PDE3 activity was blocked by the transcriptional inhibitor actinomycin D. After approximately 3 h of exposure to forskolin, PDE4 activity had increased, via a process that could be inhibited by actinomycin D, and it remained elevated for at least a 24 h period. Such actions of forskolin were mimicked by cholera toxin and 8-bromo-cAMP. Forskolin increased intracellular cAMP concentrations in a time-dependent fashion and its action was enhanced when PDE induction was blocked with actinomycin D. Reverse transcription (RT)-PCR analysis, using generic primers designed to detect transcripts representing enzymically active products of the four PDE4 genes, identified transcripts for PDE4A and PDE4D but not for PDE4B or PDE4C in untreated Jurkat T-cells. Forskolin treatment did not induce transcripts for either PDE4B or PDE4C; however, it reduced the RT-PCR signal for PDE4A transcripts and markedly enhanced that for PDE4D transcripts. Using RT-PCR primers for PDE4 splice variants, a weak signal for PDE4D1 was evident in control cells whereas, in forskolin-treated cells, clear signals for both PDE4D1 and PDE4D2 were detected. RT-PCR analysis of the PDE4A species indicated that it was not the PDE4A isoform PDE-46 (PDE4A4B). Immunoblotting of control cells for PDE4 forms identified a single PDE4A species of approximately 118 kDa, which migrated distinctly from the PDE4A4B isoform PDE-46, with immunoprecipitation analyses showing that it provided all of the PDE4 activity in control

  14. Inhibitor screening and enzymatic activity determination for autophagy target Atg4B using a gel electrophoresis-based assay.

    PubMed

    Cleenewerck, Matthias; Grootaert, Mandy O J; Gladysz, Rafaela; Adriaenssens, Yves; Roelandt, Ria; Joossens, Jurgen; Lambeir, Anne-Marie; De Meyer, Guido R Y; Declercq, Wim; Augustyns, Koen; Martinet, Wim; Van der Veken, Pieter

    2016-11-10

    Atg4B is a cysteine hydrolase that plays a key role in autophagy. Although it has been proposed as an attractive drug target, inhibitor discovery has proven highly challenging. The absence of a standardized, easily implementable enzyme activity/inhibition assay for Atg4B most likely contributes to this situation. Therefore, three different assay types for Atg4B activity/inhibition quantification were first compared: (1) an approach using fluorogenic Atg4B-substrates, (2) an in-gel densitometric quantification assay and (3) a thermal shift protocol. The gel-based approach showed the most promising results and was validated for screening of potential Atg4B inhibitors. A set of 8 literature inhibitors was included. Remarkably, in our hands only 2 literature references were found to have measurable Atg4B affinity. Furthermore, a fragment library (n = 182) was tested for Atg4B inhibition. One library member showed inhibition at high micromolar concentration and was found fit for further, fragment-based inhibitor design.

  15. The LARK/RBM4a protein is highly expressed in cerebellum as compared to cerebrum.

    PubMed

    Pfuhl, Thorsten; Mamiani, Alfredo; Dürr, Matthias; Welter, Susanne; Stieber, Johanna; Ankara, Jasmin; Liss, Michael; Dobner, Thomas; Schmitt, Andrea; Falkai, Peter; Kremmer, Elisabeth; Jung, Volker; Barth, Stephanie; Grässer, Friedrich A

    2008-10-17

    The RNA binding motif protein 4 genes RBM4a and RBM4b are located on human chromosome 11q13.2 and encode highly similar proteins of 363 and 359 amino acids, respectively. They contain two RNA recognition motifs (RRMs) and a retroviral-type Zn-finger. RBM4a binds RNA, is involved in alternative splicing and is also a part of the microRNA-processing RISC complex. In particular, RBM4a is involved in exon 10 inclusion of the tau protein. The function of RBM4b is unknown. With new monoclonal antibodies we show that RBM4a is detectable in virtually all tissues and cell lines tested while RBM4b was only found in kidney and liver. Both RBM4a and RBM4b are nuclear phosphoproteins with half-lives of 2.5h and 4.5h, respectively. To our knowledge, this is the first description of RBM4b protein in human tissue. In human brain, expression of RBM4a was strongly up-regulated in cerebellum as compared to forebrain.

  16. HATS-4b: A Dense Hot Jupiter Transiting a Super Metal-rich G star

    NASA Astrophysics Data System (ADS)

    Jordán, Andrés; Brahm, Rafael; Bakos, G. Á.; Bayliss, D.; Penev, K.; Hartman, J. D.; Zhou, G.; Mancini, L.; Mohler-Fischer, M.; Ciceri, S.; Sato, B.; Csubry, Z.; Rabus, M.; Suc, V.; Espinoza, N.; Bhatti, W.; de Val-Borro, M.; Buchhave, L.; Csák, B.; Henning, T.; Schmidt, B.; Tan, T. G.; Noyes, R. W.; Béky, B.; Butler, R. P.; Shectman, S.; Crane, J.; Thompson, I.; Williams, A.; Martin, R.; Contreras, C.; Lázár, J.; Papp, I.; Sári, P.

    2014-08-01

    We report the discovery by the HATSouth survey of HATS-4b, an extrasolar planet transiting a V = 13.46 mag G star. HATS-4b has a period of P ≈ 2.5167 days, mass of Mp ≈ 1.32 M Jup, radius of Rp ≈ 1.02 R Jup, and density of ρ p = 1.55 ± 0.16 g cm-3 ≈1.24 ρJup. The host star has a mass of 1.00 M ⊙, a radius of 0.92 R ⊙, and a very high metallicity [Fe/H]=0.43 ± 0.08. HATS-4b is among the densest known planets with masses between 1 and 2 M J and is thus likely to have a significant content of heavy elements of the order of 75 M ⊕. In this paper we present the data reduction, radial velocity measurements, and stellar classification techniques adopted by the HATSouth survey for the CORALIE spectrograph. We also detail a technique for simultaneously estimating vsin i and macroturbulence using high resolution spectra. The HATSouth network is operated by a collaboration consisting of Princeton University (PU), the Max Planck Institut für Astronomie (MPIA), and the Australian National University (ANU). The station at Las Campanas Observatory (LCO) of the Carnegie Institution is operated by PU in conjunction with collaborators at the Pontificia Universidad Católica de Chile, the station at the High Energy Spectroscopic Survey site is operated in conjunction with MPIA, and the station at Siding Spring Observatory (SSO) is operated jointly with ANU. This paper includes data gathered with the 6.5 m Magellan Telescopes located at LCO, Chile. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan, and on observations made with the MPG/ESO 2.2 m Telescope at the ESO Observatory in La Silla. This paper uses observations obtained with facilities of the Las Cumbres Observatory Global Telescope.

  17. Correcting the Redshift Measurement of 4C15.05 Using Neutral Hydrogen

    NASA Astrophysics Data System (ADS)

    Jones, Kristen M.; Ghosh, Tapasi; Salter, Christopher J.

    2017-01-01

    4C15.05, (also known as PKS 0202+14 or J0204+15), is a quintessential blazar. It has a flat radio spectrum, a super-luminal jet and gamma-ray detections. Arecibo observations with the experimental 700-800 MHz receiver on the 305-m diameter William E. Gordon Telescope detected, serendipitously, HI in absorption against 4C15.05 while using it as a bandpass calibrator for another object in an HI absorption project. Although the redshift we derive is different to than that attributed to 4C15.05 by Perlman et al. (1998), it agrees very well with the value of z=0.833 determined by Stickel et al. (1996). We note that the erroneous value of z=0.405 has been extensively used in the literature.

  18. Sputtering yield formula for B 4C irradiated with monoenergetic ions at normal incidence

    NASA Astrophysics Data System (ADS)

    Ono, T.; Kawamura, T.; Ishii, K.; Yamamura, Y.

    1996-09-01

    To fill a lack in sputtering yield data for a B 4C material which may be a promising plasma-facing material in fusion devices, the yields of H +, D +, T +, He +, B +, C +, Ne +, Ar + and Kr + ions were calculated for this multi-component material for normal incidence with a computer simulation code ACAT. A fitting formula of sputtering yield for a B 4C was proposed based on an empirical formula for monoatomic target materials at normal incidence. By fitting the formula to the calculated data, best-fit values of the parameters included in it were derived for the material. Good agreement was found between the formula and the data. Thus, the formula proposed for the multi-component material provides a way to estimate the erosion of a B 4C material irradiated with above ions at normal incidence. Preferential sputtering for this material was also mentioned briefly.

  19. Human mononuclear cell function after 4 C storage during 1-G and microgravity conditions of spaceflight

    NASA Technical Reports Server (NTRS)

    Meehan, Richard; Taylor, Gerald; Lionetti, Fabian; Neale, Laurie; Curren, Tim

    1989-01-01

    To investigate the possibility of restoring immune competence of crewmembers during a prolonged spaceflight by infusions of autologous blood components, the effect of storage at 4 C aboard Space Shuttle Columbia (Mission 61-c) on the activity of human peripheral blood mononuclear cells (PBMNCs), stored as leukocyte concentrates in autologous plasa, was investigated. The results of preflight storage at 4 C demonstrated a progressive daily loss in mitogen-stimulated protein synthesis, and thymidine uptake, as well as a progressive reduction in the percentage of PBMNCs expressing cell-surface phenotype markers. The ability of PBMNCs stored at 4 C for 8 d in Columbia's middeck, to become activated and proliferate in vitro was similar to that of cells that remained for 7 d on ground.

  20. Neutron absorption of Al-Si-Mg-B{sub 4}C composite

    SciTech Connect

    Abdullah, Yusof Yusof, Mohd Reusmaazran; Ibrahim, Anis Syukriah; Daud, Abdul Razak

    2016-01-22

    Al-Si-Mg-B{sub 4}C composites containing 2-8 wt% of B{sub 4}C were prepared by stir casting technique. Homogenization treatment was carried out at temperatures of 540°C for 4 houra and followed by ageing at 180°C for 2 houra. Microstructure and phase identification were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD) respectively. Neutron absorption study was investigated using neutron source Am/Be{sup 241}. The result indicated that higher B{sub 4}C content improved the neutron absorption property. Meanwhile homogeneity of the composite was increased by ageing processes. This composite is potential to be used as neutron shielding material especially for nuclear reactor application.

  1. Electronic shell structures of Russian-doll-style Sc 4C 2@C 80

    NASA Astrophysics Data System (ADS)

    Chen, Zhifan; Kah, Cherno B.; Wang, Xiao-Qian

    2011-04-01

    We have studied the electronic properties of a 'Russian-doll'-style endohedral fullerene Sc 4C 2@C 80 based on first-principles density-functional calculations coupled with many-body GW correction. Our calculation results yield a GW rectified gap of 1.8 eV for the 'Russian doll' structured Sc 4C 2@C 80, in very good conformity with experimental observed value of 1.6 eV. The calculated electronic characteristics of the Russian-doll fullerene reveal distinct shell structures, which are embellished in the GW approach. The analysis of vibrational frequency demonstrates profound hybridizations associated with the interactions between the Sc 4C 2 core and C 80 shell.

  2. In situ carbon coated LiFePO4/C microrods with improved lithium intercalation behavior.

    PubMed

    Bhuvaneswari, D; Kalaiselvi, N

    2014-01-28

    LiFePO4/C microrods consisting of building blocks of interconnected nanoparticles surrounded by a thin and amorphous coating of carbon have been prepared by a customized hydrothermal method. Appreciable discharge capacity values of 168 mA h g(-1) at 0.1 C and 130 mA h g(-1) at 5 C rates have been exhibited by the currently synthesized LiFePO4/C cathode. The study enumerates the feasibility of exploiting the hydrothermal method to prepare an in situ carbon coated LiFePO4/C compound with tunable morphological properties and desirable electrochemical properties observed for up to 100 cycles at a 5 C rate.

  3. Neutron absorption of Al-Si-Mg-B4C composite

    NASA Astrophysics Data System (ADS)

    Abdullah, Yusof; Ibrahim, Anis Syukriah; Daud, Abdul Razak; Yusof, Mohd Reusmaazran

    2016-01-01

    Al-Si-Mg-B4C composites containing 2-8 wt% of B4C were prepared by stir casting technique. Homogenization treatment was carried out at temperatures of 540°C for 4 houra and followed by ageing at 180°C for 2 houra. Microstructure and phase identification were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD) respectively. Neutron absorption study was investigated using neutron source Am/Be241. The result indicated that higher B4C content improved the neutron absorption property. Meanwhile homogeneity of the composite was increased by ageing processes. This composite is potential to be used as neutron shielding material especially for nuclear reactor application.

  4. Characterization of an Additional Splice Acceptor Site Introduced into CYP4B1 in Hominoidae during Evolution.

    PubMed

    Schmidt, Eva M; Wiek, Constanze; Parkinson, Oliver T; Roellecke, Katharina; Freund, Marcel; Gombert, Michael; Lottmann, Nadine; Steward, Charles A; Kramm, Christof M; Yarov-Yarovoy, Vladimir; Rettie, Allan E; Hanenberg, Helmut

    2015-01-01

    CYP4B1 belongs to the cytochrome P450 family 4, one of the oldest P450 families whose members have been highly conserved throughout evolution. The CYP4 monooxygenases typically oxidize fatty acids to both inactive and active lipid mediators, although the endogenous ligand(s) is largely unknown. During evolution, at the transition of great apes to humanoids, the CYP4B1 protein acquired a serine instead of a proline at the canonical position 427 in the meander region. Although this alteration impairs P450 function related to the processing of naturally occurring lung toxins, a study in transgenic mice suggested that an additional serine insertion at position 207 in human CYP4B1 can rescue the enzyme stability and activity. Here, we report that the genomic insertion of a CAG triplet at the intron 5-exon 6 boundary in human CYP4B1 introduced an additional splice acceptor site in frame. During evolution, this change occurred presumably at the stage of Hominoidae and leads to two major isoforms of the CYP4B1 enzymes of humans and great apes, either with or without a serine 207 insertion (insSer207). We further demonstrated that the CYP4B1 enzyme with insSer207 is the dominant isoform (76%) in humans. Importantly, this amino acid insertion did not affect the 4-ipomeanol metabolizing activities or stabilities of the native rabbit or human CYP4B1 enzymes, when introduced as transgenes in human primary cells and cell lines. In our 3D modeling, this functional neutrality of insSer207 is compatible with its predicted location on the exterior surface of CYP4B1 in a flexible side chain. Therefore, the Ser207 insertion does not rescue the P450 functional activity of human CYP4B1 that has been lost during evolution.

  5. SLC4A Transporters

    PubMed Central

    Choi, Inyeong

    2016-01-01

    SLC4A gene family proteins include bicarbonate transporters that move HCO3− across the plasma membrane and regulate intracellular pH and transepithelial movement of acid–base equivalents. These transporters are Cl/HCO3 exchangers, electrogenic Na/HCO3 cotransporters, electroneutral Na/HCO3 cotransporters, and Na+-driven Cl/HCO3 exchanger. Studies of the bicarbonate transporters in vitro and in vivo have demonstrated their physiological importance for acid–base homeostasis at the cellular and systemic levels. Recent advances in structure/function analysis have also provided valuable information on domains or motifs critical for regulation, ion translocation, and protein topology. This chapter focuses on the molecular mechanisms of ion transport along with associated structural aspects from mutagenesis of particular residues and from chimeric constructs. Structure/function studies have helped to understand the mechanism by which ion substrates are moved via the transporters. This chapter also describes some insights into the structure of SLC4A1 (AE1) and SLC4A4 (NBCe1) transporters. Finally, as some SLC4A transporters exist in concert with other proteins in the cells, the structural features associated with protein–protein interactions are briefly discussed. PMID:23177984

  6. Monoclonal antibody, mAb 4C13, an effective detoxicant antibody against ricin poisoning.

    PubMed

    Dong, Na; Luo, Longlong; Wu, Junhua; Jia, Peiyuan; Li, Qian; Wang, Yuxia; Gao, Zhongcai; Peng, Hui; Lv, Ming; Huang, Chunqian; Feng, Jiannan; Li, Hua; Shan, Junjie; Han, Gang; Shen, Beifen

    2015-07-31

    Ricin is a glycoprotein produced in castor seeds and consists of two polypeptide chains named Ricin Toxin A Chain (RTA) and Ricin Toxin B Chain (RTB), linked via a disulfide bridge. Due to its high toxicity, ricin is regarded as a high terrorist risk for the public. However, antibodies can play a pivotal role in neutralizing the toxin. In this research, the anti-toxicant effect of mAb 4C13, a monoclonal antibody (mAb) established using detoxicated ricin as the immunized antigen, was evaluated. Compared with mAb 4F2 and mAb 5G6, the effective mechanism of mAb 4C13 was analyzed by experiments relating to its cytotoxicity, epitope on ricin, binding kinetics with the toxin, its blockage on the protein synthesis inhibition induced by ricin and the intracelluar tracing of its complex with ricin. Our result indicated that mAb 4C13 could recognize and bind to RTA, RTB and exert its high affinity to the holotoxin. Both cytotoxicity and animal toxicity of ricin were well blocked by pre-incubating the toxin with mAb 4C13. By intravenous injection, mAb 4C13 could rescue the mouse intraperitoneally (ip) injected with a lethal dose of ricin (20μg/kg) even at 6h after the intoxication and its efficacy was dependent on its dosage. This research indicated that mAb 4C13 could be an excellent candidate for therapeutic antibodies. Its potent antitoxic efficiency was related to its recognition on the specific epitope with very high affinity and its blockage of protein synthesis inhibition in cytoplasm followed by cellular internalization with ricin.

  7. Octahydropyrrolo[3,4-c]pyrrole negative allosteric modulators of mGlu1

    PubMed Central

    Manka, Jason T.; Rodriguez, Alice L.; Morrison, Ryan D.; Venable, Daryl F.; Cho, Hyekyung P.; Blobaum, Anna L.; Daniels, J. Scott; Niswender, Colleen M.; Conn, P. Jeffrey; Lindsley, Craig W.; Emmitte, Kyle A.

    2014-01-01

    Development of SAR in an octahydropyrrolo[3,4-c]pyrrole series of negative allosteric modulators of mGlu1 using a functional cell-based assay is described in this Letter. The octahydropyrrolo[3,4-c]pyrrole scaffold was chosen as an isosteric replacement for the piperazine ring found in the initial hit compound. Characterization of selected compounds in protein binding assays was used to identify the most promising analogs, which were then profiled in P450 inhibition assays in order to further assess the potential for drug-likeness within this series of compounds. PMID:23932792

  8. Mechanical Properties of Injection Molded B 4C-C Ceramics

    NASA Astrophysics Data System (ADS)

    Schwetz, Karl A.; Sigl, Lorenz S.; Pfau, Lothar

    1997-10-01

    Various mechanical properties of carbon-doped boron carbide ceramics, prepared by the fabrication route, injection molding/pressureless sintering/post-hot isostatic pressing (HIP) were investigated as a function of the sintering temperature and the carbon additive level used. An optimum combination of mechanical properties (flexural stregth, fracture toughness, Young's modulus, Knoop's hardness) is thus obtained with 100% dense and very fine grained materials (mean grain size 1-4 μm) which were sintered at temperatures from 2150 to 2175°C and post-HIPed at 2050°/200 MPa Ar, having an approximate final composition of 96 B4C-4C (wt%).

  9. BOREAS Level-4b AVHRR-LAC Ten-Day Composite Images: At-sensor Radiance

    NASA Technical Reports Server (NTRS)

    Cihlar, Josef; Chen, Jing; Nickerson, Jaime; Newcomer, Jeffrey A.; Huang, Feng-Ting; Hall, Forrest G. (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study (BOREAS) Staff Science Satellite Data Acquisition Program focused on providing the research teams with the remotely sensed satellite data products they needed to compare and spatially extend point results. Manitoba Remote Sensing Center (MRSC) and BOREAS Information System (BORIS) personnel acquired, processed, and archived data from the Advanced Very High Resolution Radiometer (AVHRR) instruments on the National Oceanic and Atmospheric Administration (NOAA-11) and -14 satellites. The AVHRR data were acquired by CCRS and were provided to BORIS for use by BOREAS researchers. These AVHRR level-4b data are gridded, 10-day composites of at-sensor radiance values produced from sets of single-day images. Temporally, the 10- day compositing periods begin 11-Apr-1994 and end 10-Sep-1994. Spatially, the data cover the entire BOREAS region. The data are stored in binary image format files.

  10. Hexadecanedionic acid-sepharose 4B: A new tool for preparation of albumin-depleted plasma.

    PubMed

    Soskic, Vukic; Schwall, Gerhard; Nyakatura, Elke; Poznanovic, Slobodan; Stegmann, Werner; Schrattenholz, Andre

    2006-12-01

    Serum and plasma are the major sources of human material for clinical molecular diagnostics and drug discovery. However, due to the high abundance of some proteins, of which serum albumin (SA) is most prominent, lower-abundance proteins often remain undetectable in proteomic analysis of these body fluids. We have used hexadecanedionic acid (HDA) immobilized to Sepharose 4B to develop an affinity resin that is effective in the removal of SA from plasma. Two-dimensional gel analysis of the SA-depleted samples shows a significant enhancement of the low-abundance proteins and highly specific capture of serum albumin. The HDA resin shows better performance in terms of specificity than dye-based resins.

  11. [A novel pyridazino-fused ring system: synthesis of pyridazino[3,4-b]diazepam].

    PubMed

    Károlyházy, L; Horváth, G; Mátyus, P

    2001-08-01

    As an analogue of pyridazino-fused ring systems with pharmacological activities, the novel pyridazinol[3,4-b][1,5]diazepine ring system was prepared. The synthetic pathway includes three steps from 4 5-(N-benzyl-N-3-hydroxypropyl)amino derivative which is easily available through nucleophilic substitution reaction of the known 4,5-dichloro-2-methyl-6-nitro-3(2H)-pyridazinone (2) with N-benzyl-N-(3-hydroxypropyl)amine. In the first step, compound 4 was treated with thionyl chloride to give the chloropropyl derivative 5. In the second step, a Bechamp reduction was carried out with Fe in acetic acid to obtain the amino compound 6, and finally the ring closure reaction of 6 was performed in N,N-dimethylformamide in the presence of potassium carbonate at 110 degrees C for 40 hours. In this way the bicyclic compound 7 could be isolated in 48% yield.

  12. Low-energy Be4+/B5+ - H2 cross sections

    NASA Astrophysics Data System (ADS)

    Saha, Bidhan

    2000-06-01

    Single electron capture cross sections from molecular hydrogen by Be4+/B5+ have been calculated using the Molecular Orbital formalism in the semiclassical close-coupling scheme. The important interactions leading to state selective charge transfer are confined at large internuclear seperation. We have found that freezing the molecular details of the target turns out to be a convenient strategy [1]. In our investigation we treat H2 as a pseudo-atom with ionization potential 16.1 eV. The results will be presented in the conference. This work is supported by Research Corporation, NSF CREST and Army High Performance Computing Research. [1] A. Kumar and B C Saha, Phys Rev A 59,1273 (1999).

  13. Nitric Oxide Mediates Biofilm Formation and Symbiosis in Silicibacter sp. Strain TrichCH4B

    PubMed Central

    Rao, Minxi; Smith, Brian C.

    2015-01-01

    ABSTRACT Nitric oxide (NO) plays an important signaling role in all domains of life. Many bacteria contain a heme-nitric oxide/oxygen binding (H-NOX) protein that selectively binds NO. These H-NOX proteins often act as sensors that regulate histidine kinase (HK) activity, forming part of a bacterial two-component signaling system that also involves one or more response regulators. In several organisms, NO binding to the H-NOX protein governs bacterial biofilm formation; however, the source of NO exposure for these bacteria is unknown. In mammals, NO is generated by the enzyme nitric oxide synthase (NOS) and signals through binding the H-NOX domain of soluble guanylate cyclase. Recently, several bacterial NOS proteins have also been reported, but the corresponding bacteria do not also encode an H-NOX protein. Here, we report the first characterization of a bacterium that encodes both a NOS and H-NOX, thus resembling the mammalian system capable of both synthesizing and sensing NO. We characterized the NO signaling pathway of the marine alphaproteobacterium Silicibacter sp. strain TrichCH4B, determining that the NOS is activated by an algal symbiont, Trichodesmium erythraeum. NO signaling through a histidine kinase-response regulator two-component signaling pathway results in increased concentrations of cyclic diguanosine monophosphate, a key bacterial second messenger molecule that controls cellular adhesion and biofilm formation. Silicibacter sp. TrichCH4B biofilm formation, activated by T. erythraeum, may be an important mechanism for symbiosis between the two organisms, revealing that NO plays a previously unknown key role in bacterial communication and symbiosis. PMID:25944856

  14. Cul4A is essential for spermatogenesis and male fertility.

    PubMed

    Kopanja, Dragana; Roy, Nilotpal; Stoyanova, Tanya; Hess, Rex A; Bagchi, Srilata; Raychaudhuri, Pradip

    2011-04-15

    The mammalian Cul4 genes, Cul4A and Cul4B, encode the scaffold components of the cullin-based E3 ubiquitin ligases. The two Cul4 genes are functionally redundant. Recent study indicated that mice expressing a truncated CUL4A that fails to interact with its functional partner ROC1 exhibit no developmental phenotype. We generated a Cul4A-/- strain lacking exons 4-8 that does not express any detectable truncated protein. In this strain, the male mice are infertile and exhibit severe deficiencies in spermatogenesis. The primary spermatocytes are deficient in progression through late prophase I, a time point when expression of the X-linked Cul4B gene is silenced due to meiotic sex chromosome inactivation. Testes of the Cul4A-/- mice exhibit extensive apoptosis. Interestingly, the pachytene spermatocytes exhibit persistent double stranded breaks, suggesting a deficiency in homologous recombination. Also, we find that CUL4A localizes to the double stranded breaks generated in pre-pachytene spermatocytes. The observations identify a novel function of CUL4A in meiotic recombination and demonstrate an essential role of CUL4A in spermatogenesis.

  15. Magnetic anisotropy and crystalline electric field effects in RRh{sub 4}B{sub 4} single crystals.

    SciTech Connect

    Zhou, H.; Lambert, S. E.; Maple, M. B.; Dunlap, B. D.; Materials Science Division; Univ. of California at San Diego

    2009-08-01

    Research on polycrystalline RRh{sub 4}B{sub 4} samples has shown that crystalline electric field (CEF) effects play an important role in these compounds. The successful synthesis of single crystal samples of RRh{sub 4}B{sub 4} with R = Y, Sm, Gd, Tb, Dy, Ho, Er, Tm, and Lu has provided an opportunity to further investigate CEF effects in these materials. Magnetization and magnetic susceptibility measurements on the RRh{sub 4}B{sub 4} single crystals revealed strong magnetic anisotropy, and the experimental results could be described well by CEF calculations based on the parameters derived from an analysis of experimental data for ErRh{sub 4}B{sub 4} single crystals. The easy directions of magnetization of these compounds are consistent with the signs of the Stevens factor {alpha}J of the CEF Hamiltonian. A strong influence of magnetic anisotropy on superconductivity was also observed.

  16. 75 FR 43172 - International Conference on Harmonisation; Draft Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... Recommendation of Pharmacopoeial Texts for Use in the ICH Regions; Annex 13: Bulk Density and Tapped Density...

  17. Possible role for increased C4b-binding-protein level in acquired protein S deficiency in type I diabetes.

    PubMed

    Ceriello, A; Giugliano, D; Quatraro, A; Marchi, E; Barbanti, M; Lefebvre, P

    1990-04-01

    In this study, total protein S (PS) immunological levels, free-PS and C4b-binding-protein (C4bBP) concentrations, and PS functional activity were investigated in insulin-dependent (type I) diabetic patients and compared with nondiabetic subjects. Mean total PS antigen concentration was not different between diabetic patients and nondiabetic subjects, whereas free-PS levels and PS functional activity were significantly reduced in diabetic patients. C4bBP was increased in diabetic patients and correlated with HbA1 levels. This study shows that type I diabetic patients have depressed free PS and PS activity despite the presence of normal total PS concentration and suggests that this phenomenon is probably linked to the increase of circulating C4bBP.

  18. Relationship between LAPTM4B Gene Polymorphism and Prognosis of Patients following Tumor Resection for Colorectal and Esophageal Cancers

    PubMed Central

    Xing, Xiaofang; Du, Hong; Zhou, Chunlian; Zhang, Qingyun; Hao, Chunyi; Wen, Xianzi; Ji, Jiafu

    2016-01-01

    Background Lysosome-associated transmembrane-4 beta (LAPTM4B) is an oncogene that participates tumorgenesis in a variety of human solid tumors, and it has two alleles named as LAPTM4B*1 and *2. The present study aimed to identify the association of LAPTM4B genotype with clinicopathological features and prognosis in colorectal and esophageal cancer patients. Method Genotypes of LAPTM4B were determined by PCR in 167 colon cancer cases (72 patients in a discovery cohort and 95 patients in a testing cohort), 160 rectal cancer cases and 164 esophageal cancer cases. Association between the LAPTM4B gene polymorphism and clinicopathological variables was calculated by Chi-square test or Fisher’s exact test. Patient survival differences were calculated by the Kaplan-Meier method. Prognostic factors were determined with Log-rank test and Cox regression model. Results LAPTM4B *1/1 was more frequently detected in colon cancer patients with lymph node metastasis and TNM III+IV stages in total colon cancer (discovery + testing cohorts). LAPTM4B *2/2 decreased in recurrent patients in total colon cancer patients (P = 0.045). Kaplan-Meier survival curves and Log-rank test showed that LAPTM4B*1 was correlated with shorter overall survival (OS) in discovery and testing cohorts of colon cancer (P = 0.0254 and 0.0292, respectively), but not in rectal and esophageal cancer cases (P = 0.7669 and 0.9356, respectively). Multivariate analysis showed that LAPTM4B genotype was an independent prognostic factor for OS in total colon cancer [P = 0.004, hazard ratio (HR) = 0.432; 95% confidence interval (CI) = 0.243–0.768], but not in rectal and esophageal cancers (P = 0.791, HR = 1.073, 95% CI = 0.638–1.804 and 0.998, HR = 1.000, 95% CI = 0.663–1.530, respectively). Conclusion These findings suggested that LAPTM4B allele *1 was a risk factor associated with poor prognosis in patients with colon cancer, but not in patients with rectal or esophageal cancers. LAPTM4B genotype status might

  19. FROM "CANAL BRIDGE, F.A.P. 4C, MAR. 1938." SHOWING WAIKELE BRIDGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FROM "CANAL BRIDGE, F.A.P. 4-C, MAR. 1938." SHOWING WAIKELE BRIDGE PLAN AND ELEVATION. Hawaii Department of Transportation, Design Branch, Project ID 7101-001, drawing 4449.27. - Waikele Canal Bridge and Highway Overpass, Farrington Highway and Waikele Stream, Waipahu, Honolulu County, HI

  20. Tribological behavior of liquid metallurgy-processed AA 6061-B4C composites

    NASA Astrophysics Data System (ADS)

    Monikandan, V. V.; Joseph, M. A.; Rajendrakumar, P. K.; Sreejith, M.

    2015-01-01

    Aluminum metal matrix composites (AMMCs) possess improved properties compared to their monolithic counterparts and serve as a reliable alternative to replace them for applications that are considered as their niche. In the present investigation, 6061 Al alloy-10 wt% B4C composite is fabricated through liquid metallurgy stir casting technique and analyzed for its tribological characteristics. The uniform distribution of B4C reinforcement particles in the composite is achieved by the above route and is characterized using microstructure analysis and x-ray diffraction spectrum. The dry wear tests have been conducted under ambient conditions using a pin-on-disc tribometer. The worn surface and debris of the composite are also characterized using a scanning electron microscope (SEM) and energy-dispersive x-ray spectroscopy (EDS). It is found that the combination of adhesion, delamination and abrasion constitute the predominant wear mechanism and this is influenced by the B4C particles, applied load, sliding distance and speed. The wear and friction coefficient increase with increase in applied load for all the load conditions studied. While the sliding speed fosters the engendering of a mechanically mixed layer (MML) to reduce the wear and friction coefficient, in contrast, the increase in sliding distance scuttles the MML formation owing to abrasion induced by the hard B4C particles.

  1. The 4C technique: the 'Rosetta stone' for genome biology in 3D?

    PubMed

    Ohlsson, Rolf; Göndör, Anita

    2007-06-01

    Despite considerable efforts, the spatial link between the nuclear architecture and the genome remains enigmatic. The 4C method, independently innovated in four different laboratories, might in combination with other methods change that. As this method is based on the unbiased identification of sequences interacting with specific baits, there are unique opportunities for unravelling the secrets of how the genome functions in 3D.

  2. Numerical stability of the Z4c formulation of general relativity

    NASA Astrophysics Data System (ADS)

    Cao, Zhoujian; Hilditch, David

    2012-06-01

    We study numerical stability of different approaches to the discretization of a conformal decomposition of the Z4 formulation of general relativity. We demonstrate that in the linear, constant coefficient regime a novel discretization for tensors is formally numerically stable with a method of lines time integrator. We then perform a full set of “apples with apples” tests on the nonlinear system, and thus present numerical evidence that both the new and standard discretizations are, in some sense, numerically stable in the nonlinear regime. The results of the Z4c numerical tests are compared with those of Baumgarte-Shapiro-Shibata-Nakamura-Oohara-Kojima (BSSNOK) evolutions. We typically do not employ the Z4c constraint damping scheme and find that in the robust stability and gauge wave tests the Z4c evolutions result in lower constraint violation at the same resolution as the BSSNOK evolutions. In the gauge wave tests, we find that the Z4c evolutions maintain the desired convergence factor over many more light-crossing times than the BSSNOK tests. The difference in the remaining tests is marginal.

  3. 29 CFR 4.163 - Section 4(c) of the Act.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... “it was the clear intent of Congress that any revised wage determinations resulting from a section 4(c) proceeding were to have validity with respect to the procurement involved” (53 Comp. Gen. 401, 402, 1973... Review Board, the date of that decision. The legislative history of the 1972 Amendments makes clear...

  4. 29 CFR 4.163 - Section 4(c) of the Act.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... “it was the clear intent of Congress that any revised wage determinations resulting from a section 4(c) proceeding were to have validity with respect to the procurement involved” (53 Comp. Gen. 401, 402, 1973... Review Board, the date of that decision. The legislative history of the 1972 Amendments makes clear...

  5. 29 CFR 4.163 - Section 4(c) of the Act.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... “it was the clear intent of Congress that any revised wage determinations resulting from a section 4(c) proceeding were to have validity with respect to the procurement involved” (53 Comp. Gen. 401, 402, 1973... Review Board, the date of that decision. The legislative history of the 1972 Amendments makes clear...

  6. 29 CFR 4.163 - Section 4(c) of the Act.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... “it was the clear intent of Congress that any revised wage determinations resulting from a section 4(c) proceeding were to have validity with respect to the procurement involved” (53 Comp. Gen. 401, 402, 1973... Review Board, the date of that decision. The legislative history of the 1972 Amendments makes clear...

  7. 29 CFR 4.163 - Section 4(c) of the Act.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... “it was the clear intent of Congress that any revised wage determinations resulting from a section 4(c) proceeding were to have validity with respect to the procurement involved” (53 Comp. Gen. 401, 402, 1973... Review Board, the date of that decision. The legislative history of the 1972 Amendments makes clear...

  8. The compact radio sources in 4C 39.25 and 3C 345. [quasars

    NASA Technical Reports Server (NTRS)

    Shaffer, D. B.; Kellermann, K. I.; Purcell, G. H.; Pauliny-Toth, I. I. K.; Preuss, E.; Witzel, A.; Graham, D.; Schilizzi, R. T.; Cohen, M. H.; Niell, A. E.

    1977-01-01

    Long-baseline interferometry of the quasars 4C 39.25 and 3C 345 at 10.65 and 14.77 GHz shows that the centimeter radio source in each object is double, with component separations of 0.0020 arcsec (4C 39.25) and 0.0013 arcsec (3C 345 at 1974.5). For each source, the separation is the same at both frequencies, as well as similar to the structure observed at 7.85 GHz (and 5.0 GHz for 4C 39.25). The spectra of the individual components are derived and shown to vary with time approximately as expected for expanding self-absorbed synchrotron sources. The magnetic fields in the components are estimated to be as high as 0.1 gauss, but the structure of the sources appears to be unrelated to the magnetic-field orientation derived from low-resolution polarization measurements. The component separation in 4C 39.25 has not changed for several years, whereas 3C 345 shows rapid expansion.

  9. Recent radio activity of the Fermi blazar 4C +38.41

    NASA Astrophysics Data System (ADS)

    Myserlis, I.; Angelakis, E.; Fuhrmann, L.; Karamanavis, V.; Nestoras, I.; Krichbaum, T. P.; Zensus, J. A.; Ungerechts, H.; Sievers, A.

    2012-10-01

    We report the recent activity (raising flux density) seen in the monitored blazar 4C +38.41 (J1635+3808, RA= 16:35:16, DEC=+38:08:05 in J2000), as recorded within the framework of the F-GAMMA program responding to ATels #4389, #4400 and #4437 (gamma, NIR and optical respectively).

  10. Escape Mutations in NS4B Render Dengue Virus Insensitive to the Antiviral Activity of the Paracetamol Metabolite AM404.

    PubMed

    van Cleef, Koen W R; Overheul, Gijs J; Thomassen, Michael C; Marjakangas, Jenni M; van Rij, Ronald P

    2016-04-01

    Despite the enormous disease burden associated with dengue virus infections, a licensed antiviral drug is lacking. Here, we show that the paracetamol (acetaminophen) metabolite AM404 inhibits dengue virus replication. Moreover, we find that mutations in NS4B that were previously found to confer resistance to the antiviral compounds NITD-618 and SDM25N also render dengue virus insensitive to AM404. Our work provides further support for NS4B as a direct or indirect target for antiviral drug development.

  11. Soil Moisture Active Passive Mission L4_C Data Product Assessment (Version 2 Validated Release)

    NASA Technical Reports Server (NTRS)

    Kimball, John S.; Jones, Lucas A.; Glassy, Joseph; Stavros, E. Natasha; Madani, Nima; Reichle, Rolf H.; Jackson, Thomas; Colliander, Andreas

    2016-01-01

    The SMAP satellite was successfully launched January 31st 2015, and began acquiring Earth observation data following in-orbit sensor calibration. Global data products derived from the SMAP L-band microwave measurements include Level 1 calibrated and geolocated radiometric brightness temperatures, Level 23 surface soil moisture and freezethaw geophysical retrievals mapped to a fixed Earth grid, and model enhanced Level 4 data products for surface to root zone soil moisture and terrestrial carbon (CO2) fluxes. The post-launch SMAP mission CalVal Phase had two primary objectives for each science product team: 1) calibrate, verify, and improve the performance of the science algorithms, and 2) validate accuracies of the science data products as specified in the L1 science requirements. This report provides analysis and assessment of the SMAP Level 4 Carbon (L4_C) product pertaining to the validated release. The L4_C validated product release effectively replaces an earlier L4_C beta-product release (Kimball et al. 2015). The validated release described in this report incorporates a longer data record and benefits from algorithm and CalVal refinements acquired during the SMAP post-launch CalVal intensive period. The SMAP L4_C algorithms utilize a terrestrial carbon flux model informed by SMAP soil moisture inputs along with optical remote sensing (e.g. MODIS) vegetation indices and other ancillary biophysical data to estimate global daily net ecosystem CO2 exchange (NEE) and component carbon fluxes for vegetation gross primary production (GPP) and ecosystem respiration (Reco). Other L4_C product elements include surface (10 cm depth) soil organic carbon (SOC) stocks and associated environmental constraints to these processes, including soil moisture and landscape freeze/thaw (FT) controls on GPP and respiration (Kimball et al. 2012). The L4_C product encapsulates SMAP carbon cycle science objectives by: 1) providing a direct link between terrestrial carbon fluxes and

  12. High-temperature mass spectrometry - Vaporization of group 4-B metal carbides. [using Knudsen effusion

    NASA Technical Reports Server (NTRS)

    Stearns, C. A.; Kohl, F. J.

    1974-01-01

    The high temperature vaporization of the metal-carbon systems TiC, ZrC, HfC, and ThC was studied by the Knudsen effusion - mass spectrometric method. For each system the metal dicarbide and tetracarbide molecular species were identified in the gas phase. Relative ion currents of the carbides and metals were measured as a function of temperature. Second- and third-law methods were used to determine enthalpies. Maximum values were established for the dissociation energies of the metal monocarbide molecules TiC, ZrC, HfC, and ThC. Thermodynamic functions used in the calculations are discussed in terms of assumed molecular structures and electronic contributions to the partition functions. The trends shown by the dissociation energies of the carbides of Group 4B are compared with those of neighboring groups and discussed in relation to the corresponding oxides and chemical bonding. The high temperature molecular beam inlet system and double focusing mass spectrometer are described.

  13. Study of Historical 4B/X17 Mega Flare on 28 October 2003 (P58)

    NASA Astrophysics Data System (ADS)

    Uddin, W.; Chandra, R.; Ali, S. S.

    2006-11-01

    wuddin_99@yahoo.com We analysed multi-wavelength data of 28 October 2003 4B/X17.2 class extremely energetic parallel ribbon solar flare, which occurred in NOAA 10486. The flare was well observed in H-alpha at ARIES, Nainital and various space (SOHO, TRACE, RHESSI, WIND etc.) and ground based Observatories. The H-alpha observations show the stretching/detwisting and eruption of helically twisted S shaped (sigmoid) filament in the South-West direction of the active region with bright shock front followed by rapid increase in intensity and area of the gigantic flare. The flare is associated with a bright/fast full halo earth directed CME, strong type II, III and IV radio bursts, an intense proton event and GLE. It seems that the filament eruption triggered the halo CME because the helical structure is clearly visible in the SOHO/LASCO C2, C3 images. This indicates helicity transfer from chromosphere to corona and interplanetary medium. The magnetic field of the flaring region was most complex with high magnetic shear. From the above analysis we feel that the energy buildup/release process of this unique flare support helically twisted magnetic flux rope model.

  14. Intramolecular cycloaddition reactions of furo[3,4-b]indoles for alkaloid synthesis.

    PubMed

    Padwa, Albert; Zou, Yan; Cheng, Bo; Li, Hao; Downer-Riley, Nadale; Straub, Christopher S

    2014-04-04

    Model studies dealing with the Cu(II)- or Rh(II)-catalyzed carbenoid cyclization/cycloaddition cascade of several α-diazo indolo amido esters have been carried out as an approach to the alkaloid scandine. The Cu(II)-catalyzed reaction of an α-diazo indolo diester that contains a tethered oxa-pentenyl side chain was found to give rise to a reactive benzo[c]furan which undergoes a subsequent [4 + 2]-cycloaddition across the tethered π-bond. The reaction proceeds by the initial generation of a copper carbenoid intermediate which cyclizes onto the adjacent carbonyl group to give a reactive benzo[c]furan which in certain cases can be isolated. Disappointingly, the analogous reaction with the related amido indolo ester failed to take place, even when the tethered π-bond contained an electron-withdrawing carbomethoxy group. It would seem that the geometric requirements for the intramolecular cycloaddition of the furo[3,4-b]indole system with the tethered π-bond imposes distinct restrictions upon the bond angles of the reacting centers to prevent the cycloaddition reaction from occurring. However, the incorporation of another carbonyl group on the nitrogen atom of the tethered alkenyl diazo amido indolo ester seemingly provides better orbital overlap between the reacting π-systems and allows the desired cycloaddition reaction to occur.

  15. Inositol polyphosphate 4-phosphatase II (INPP4B) is associated with chemoresistance and poor outcome in AML.

    PubMed

    Rijal, Sewa; Fleming, Shaun; Cummings, Nik; Rynkiewicz, Natalie K; Ooms, Lisa M; Nguyen, Nhu-Y N; Teh, Tse-Chieh; Avery, Sharon; McManus, Julie F; Papenfuss, Anthony T; McLean, Catriona; Guthridge, Mark A; Mitchell, Christina A; Wei, Andrew H

    2015-04-30

    Phosphoinositide signaling regulates diverse cellular functions. Phosphoinositide-3 kinase (PI3K) generates PtdIns(3,4,5)P3 and PtdIns(3,4)P2, leading to the activation of proliferative and anti-apoptotic signaling pathways. Termination of phosphoinositide signaling requires hydrolysis of inositol ring phosphate groups through the actions of PtdIns(3,4,5)P3 3-phosphatase (PTEN), PtdIns(3,4,5)P3 5-phosphatases (eg, SHIP), and PtdIns(3,4)P2 4-phosphatases (eg, INPP4B). The biological relevance of most of these phosphoinositide phosphatases in acute myeloid leukemia (AML) remains poorly understood. Mass spectrometry-based gene expression profiling of 3-, 4- and 5-phosphatases in human AML revealed significant overexpression of INPP4B. Analysis of an expanded panel of 205 AML cases at diagnosis revealed INPP4B overexpression in association with reduced responses to chemotherapy, early relapse, and poor overall survival, independent of other risk factors. Ectopic overexpression of INPP4B conferred leukemic resistance to cytosine arabinoside (ara-C), daunorubicin, and etoposide. Expression of a phosphatase inert variant (INPP4B C842A) failed to abrogate resistance of AML cells to chemotherapy in vitro or in vivo. In contrast, targeted suppression of endogenously overexpressed INPP4B by RNA interference sensitized AML cell lines and primary AML to chemotherapy. These findings demonstrate a previously unsuspected and clinically relevant role for INPP4B gain of function as a mediator of chemoresistance and poor survival outcome in AML independent of its phosphoinositide phosphatase function.

  16. Reaction behavior between B4C, 304 grade of stainless steel and Zircaloy at 1473 K

    NASA Astrophysics Data System (ADS)

    Sasaki, Ryosuke; Ueda, Shigeru; Kim, Sun-Joong; Gao, Xu; Kitamura, Shin-ya

    2016-08-01

    For a better understanding of the decommissioning of the Fukushima-daiichi nuclear power plant, the melting behavior of the control blade and the channel box should be clarified. In Fukushima nuclear reactor, the channel box was made of Zircaloy-4, and the control rode is made of B4C together with stainless steel cladding and sheath. In the study, the interaction among B4C, stainless steel (SUS), and Zircaloy-4 was investigated at 1473 K in either argon or air atmosphere. In argon, Zircaloy is melted by the diffusion of elements from SUS, and SUS was melted at 1473 K by the diffusion of C and B. In air, SUS reacted with B2O3 and formed an oxides melt firstly. Then, the oxidized Zircaloy contacted with this melt and fused. Moreover, the progress of core melting process during severe accident under different atmospheres was firstly discussed.

  17. Determination of Optimum Cutting Parameters for Surface Roughness in Turning AL-B4C Composites

    NASA Astrophysics Data System (ADS)

    Channabasavaraja, H. K.; Nagaraj, P. M.; Srinivasan, D.

    2016-09-01

    Many materials such as alloys, composites find their applications on the basis of machinability, cost and availability. In the present work, machinability of Aluminium 1100 and Boron carbide (AL+ B4C) composite material is examined by using lathe tool dynometers (BANKA Lathe) by varying the cutting parameters like spindle speed, Depth of cut and Feed rate in 3 levels. Also, surface roughness is measured against the weight % of reinforcement in the composite (0, 4 and 8 %). From the study it is observed that the hardness of a composite material increases with increase in weight % of reinforcement material (B4C) by 26.27 and 66.7 % respectively. The addition of reinforcement materials influences the machinability. The cutting force in both X and Z direction were also found increment with the reinforcement percentage.

  18. Cr/B4C multilayer mirrors: Study of interfaces and X-ray reflectance

    DOE PAGES

    Burcklen, C.; Soufli, R.; Gullikson, E.; ...

    2016-03-24

    Here, we present an experimental study of the effect of layer interfaces on the x-ray reflectance in Cr/B4C multilayer interference coatings with layer thicknesses ranging from 0.7 nm to 5.4 nm. The multilayers were deposited by magnetron sputtering and by ion beam sputtering. Grazing incidence x-ray reflectometry, soft x-ray reflectometry, and transmission electron microscopy reveal asymmetric multilayer structures with a larger B4C-on-Cr interface, which we modeled with a 1–1.5 nm thick interfacial layer. Reflectance measurements in the vicinity of the Cr L2,3 absorption edge demonstrate fine structure that is not predicted by simulations using the currently tabulated refractive index (opticalmore » constants) values for Cr.« less

  19. Computational fluid flow in two dimensions using simple T4/C3 element

    NASA Astrophysics Data System (ADS)

    Jan, Y. J.; Huang, S. J.; Lee, T. Y.

    2000-10-01

    The application of the four nodes for velocity and three nodes for pressure (T4/C3) element discretization technique for simulating two-dimensional steady and transitional flows is presented. The newly developed code has been validated by the application to three benchmark test cases: driven cavity flow, flow over a backward-facing step, and confined surface rib flow. In addition, a transitional flow with vortex shedding has been studied. The numerical results have shown excellent agreement with experimental results, as well as with those of other simulations. It should be pointed out that the advantages of the T4/C3 finite element over other higher-order elements lie in its computational simplicity, efficiency, and less computer memory requirement. Copyright

  20. 13. 'Portal and Transverse Bracing, 1 180'01/4' c. to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. 'Portal and Transverse Bracing, 1 - 180'-0-1/4' c. to c. end pins S. Tr. Thro. Truss Span, 16th Crossing Sacramento River, Sacramento Division, So. Pac. Co., The Phoenix Bridge Co., C.O. #842, Draw #6, Engineer C. Scheidl, Draftsman Hermanns, Scale 1' = 1', Apr. 26, 1901.' - Southern Pacific Railroad Shasta Route, Bridge No. 324.99, Milepost 324.99, Shasta Springs, Siskiyou County, CA

  1. Regulation of neuropathic pain behavior by amygdaloid TRPC4/C5 channels.

    PubMed

    Wei, Hong; Sagalajev, Boriss; Yüzer, M Anil; Koivisto, Ari; Pertovaara, Antti

    2015-11-03

    Pain per se may increase anxiety and conversely, anxiety may increase pain. Therefore, a positive feedback loop between anxiety and pain possibly contributes to pain and suffering in some pathophysiological pain conditions, such as that induced by peripheral nerve injury. Recent results indicate that transient receptor channels 4 and 5 (TRPC4/C5) in the amygdala have anxiogenic effects in rodents, while their role in chronic pain conditions is not known. Here, we studied whether the amygdaloid TRPC4/C5 that are known to have anxiogenic properties contribute to the maintenance of sensory or affective aspects of pain in an experimental model of peripheral neuropathy. Rats with a spared nerve injury (SNI) model of neuropathy in the left hind limb had a chronic cannula for microinjections of drugs into the right amygdala or the internal capsule (a control site). Sensory pain was assessed by determining mechanical hypersensitivity with calibrated monofilaments and affective pain by determining aversive place-conditioning. Amygdaloid treatment with ML-204, a TRPC4/C5 antagonist, produced a dose-related (5-10 μg) antihypersensitivity effect, without obvious side-effects. Additionally, amygdaloid administration of ML-204 reduced affective-like pain behavior. In the internal capsule, ML-204 had no effect on hypersensitivity or affective-like pain in SNI animals. In healthy controls, amygdaloid administration of ML-204 failed to influence pain behavior induced by mechanical stimulation or noxious heat. The results indicate that the amygdaloid TRPC4/C5 contribute to maintenance of pain hypersensitivity and pain affect in neuropathy.

  2. 12. 'Erection Plan, 1 180'01/4' c. to c. End ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. 'Erection Plan, 1 - 180'-0-1/4' c. to c. End Pins Sing. Tr. Thro' Span, 16th Crossing over Sacramento River, Pacific System, Southern Pacific Co., Phoenix Bridge Co., C.O. #842, Drawing #13, Scale 1/8' & 1' = 1'-0', Eng'r C. Scheidl, Draftsman D. Sharp, Scale 1' = 1'-0', May 1st 1901.' - Southern Pacific Railroad Shasta Route, Bridge No. 324.99, Milepost 324.99, Shasta Springs, Siskiyou County, CA

  3. The 4C framework for making reasonable adjustments for people with learning disabilities.

    PubMed

    Marsden, Daniel; Giles, Rachel

    2017-01-18

    Background People with learning disabilities experience significant inequalities in accessing healthcare. Legal frameworks, such as the Equality Act 2010, are intended to reduce such disparities in care, and require organisations to make 'reasonable adjustments' for people with disabilities, including learning disabilities. However, reasonable adjustments are often not clearly defined or adequately implemented in clinical practice. Aim To examine and synthesise the challenges in caring for people with learning disabilities to develop a framework for making reasonable adjustments for people with learning disabilities in hospital. This framework would assist ward staff in identifying and managing the challenges of delivering person-centred, safe and effective healthcare to people with learning disabilities in this setting. Method Fourth-generation evaluation, collaborative thematic analysis, reflection and a secondary analysis were used to develop a framework for making reasonable adjustments in the hospital setting. The authors attended ward manager and matron group meetings to collect their claims, concerns and issues, then conducted a collaborative thematic analysis with the group members to identify the main themes. Findings Four main themes were identified from the ward manager and matron group meetings: communication, choice-making, collaboration and coordination. These were used to develop the 4C framework for making reasonable adjustments for people with learning disabilities in hospital. Discussion The 4C framework has provided a basis for delivering person-centred care for people with learning disabilities. It has been used to inform training needs analyses, develop audit tools to review delivery of care that is adjusted appropriately to the individual patient; and to develop competencies for learning disability champions. The most significant benefit of the 4C framework has been in helping to evaluate and resolve practice-based scenarios. Conclusion Use of

  4. Characterization of Al–Al{sub 4}C{sub 3} nanocomposites produced by mechanical milling

    SciTech Connect

    Santos-Beltrán, A.; Morales-Rodriguez, H.; Gallegos-Orozco, V.; Baldenebro-Lopez, F.

    2015-08-15

    In this work, a mixture of Al–C–Al{sub 4}C{sub 3} nanopowder previously synthesized by mechanical milling and subsequent thermal treatment was used to reinforce the Al matrix. The nanocomposites were fabricated via high-energy ball milling and subsequent sintering process for different periods of time at 550 °C. Hardness and compression tests were performed to evaluate the mechanical properties of the nanocomposites in the as-milled and sintered conditions. According to the results the reinforcement located in the grain boundaries is responsible for the brittle behavior observed in the nanocomposites during the compression test. The combined effect of sintering and precipitation mechanisms produced an evident increase of the strength of the Al matrix at a relatively short sintering time. By using the Rietveld method the crystallite size and microstrain measurements were determined and correlated with the microhardness values. For the proper characterization of the nanoparticles present in the Al matrix, atomic force microscopy and high resolution electron microscopy were used. - Highlights: • Nanostructured Al{sub 4}C{sub 3} reinforcement was fabricated via mechanical milling and heat treatment. • We found a significant increase of the mechanical properties at short sintering times. • The formation of Al{sub 4}C{sub 3} with during sintering time restricted the excessive growth of the crystallite. • Al{sub 4}C{sub 3} located in the grain boundaries causes brittle fracture observed in compression tests. • There is a correlation between, crystallite size and microstrain values with microhardness.

  5. Broad band radio outburst of gamma-ray flaring blazar 4C+28.07

    NASA Astrophysics Data System (ADS)

    Nestoras, I.; Fuhrmann, L.; Angelakis, E.; Schmidt, R.; Krichbaum, T. P.; Zensus, J. A.; Ungerechts, H.; Sievers, A.; Riquelme, D.

    2011-10-01

    Responding to ATel #3670 reporting the recent Fermi LAT flaring activity of 4C+28.07 (J0237+2848) at gamma-rays on October 3, 2011, and the optical follow-up reported in ATel #3672, we here report its past and recent behavior at radio bands as observed by the F GAMMA program. Long-term activity: The source has been observed with the Effelsberg 100-m and the IRAM 30-m telescopes since January and June 2007, respectively.

  6. Crystal structure of 7-isopropyl-1,4a,N-trimethyl-1,2,3,4,4a,4b,5,6,7,8,10,10a-dodeca-hydro-phenanthrene-1-carb-ox-amide.

    PubMed

    Liu, Li; Yan, Xin-Yan; Rao, Xiao-Ping

    2015-10-01

    In the title compound, C26H37NO, a new derivative of di-hydro-abietic acid, the two cyclo-hexene rings adopt half chair conformations, whereas the cyclo-hexane ring has a chair conformation. Each of the methyl groups is in an axial position with respect to the tricyclic hydro-phenanthrene residue. In the crystal packing, methyl-ene-C-H⋯π(phen-yl) inter-actions lead to supra-molecular helical chains along [010]; the amide-H atom does not form a significant inter-molecular inter-action owing to steric pressure.

  7. When galaxies collide: understanding the broad absorption-line radio galaxy 4C +72.26

    NASA Astrophysics Data System (ADS)

    Smith, D. J. B.; Simpson, C.; Swinbank, A. M.; Rawlings, S.; Jarvis, M. J.

    2010-05-01

    We present a range of new observations of the `broad absorption-line radio galaxy' 4C +72.26 (z ~ 3.5), including sensitive rest-frame ultraviolet integral field spectroscopy using the Gemini/GMOS-N instrument and Subaru/CISCO K-band imaging and spectroscopy. We show that 4C +72.26 is a system of two vigorously star-forming galaxies superimposed along the line of sight separated by ~1300 +/- 200 km s-1 in velocity, with each demonstrating spectroscopically resolved absorption lines. The most active star-forming galaxy also hosts the accreting supermassive black hole which powers the extended radio source. We conclude that the star formation is unlikely to have been induced by a shock caused by the passage of the radio jet, and instead propose that a collision is a more probable trigger for the star formation. Despite the massive starburst, the ultraviolet-mid-infrared spectral energy distribution suggests that the pre-existing stellar population comprises ~1012Msolar of stellar mass, with the current burst only contributing a further ~2 per cent, suggesting that 4C +72.26 has already assembled most of its final stellar mass.

  8. Analysis of Particle Distribution in Milled Al-Based Composites Reinforced by B4C Nanoparticles

    NASA Astrophysics Data System (ADS)

    Alihosseini, Hamid; Dehghani, Kamran

    2017-03-01

    In the present work, high-energy ball milling was employed to synthesize Al-(5-10 wt.%)B4C nanocomposite. To do this, two sizes of particles of 50 nm as nanoparticles (NPs) and 50 μm as coarse particles (CPs) were used. The morphology and microstructure of the milled powders were characterized using particle size analyzer, SEM, TEM and EDX techniques. It was found that milling time, B4C particles size and their content strongly affect the characteristics of powders during milling process. The breaking and cold welding of powders was recognized as two main competitive actions during the milling process that influence the microstructural evolutions. It was found that the presence of CPs led to the formation of microcracks which promote the fracture process of Al powders. The dominated mechanisms during the fabrication of composites and nanocomposites were discussed. Also, the theoretical issues regarding the changes in morphology and distribution of B4C particles in CPs and NPs are clarified.

  9. Microstructure and mechanical properties of pressureless sintered B4C- C composite using phenolic resin

    NASA Astrophysics Data System (ADS)

    Nikravan, A.; Baharvandi, H. R.; Jebelli, F. B.; Abdizadeh, H.; Ehsani, N.

    2007-10-01

    Boron carbide is an extremely promising material for a variety of applications that require high hardness and good wear resistance. However, due to the very high sintering temperatures which are required for B4C densification, wide spread use of that is limited. Various solutions have been studied to modifying densification behavior of B4C. Pressureless sintering in the presence of different additives has been tried by researchers. The effect of additives such as TiB2, SiC, Al, B, ZrO2, talc and Si have been evaluated. It was shown that the densification and mechanical properties may be improved with sintering aids. The Effects of phenolic resin additive on the microstructure and mechanical properties of B4C were explained in this study. Experimental composition was batched corresponding from 0 to 10 wt% of the additive. All samples were sintered for 60 minutes at 2150°C. The heating and cooling rates were 10°C/min for all samples. It was found that below 7.5 wt% of phenolic resin additive, the density increased with additive increasing and above that, decreased by phenolic resin addition. Mechanical properties such as fracture toughness, strength and hardness increased as a result of densification enhancement.

  10. Microstructure and mechanical properties of pressureless sintered B 4C-C composite using phenolic resin

    NASA Astrophysics Data System (ADS)

    Nikravan, A.; Baharvandi, H. R.; Jebelli, F. B.; Abdizadeh, H.; Ehsani, N.

    2007-07-01

    Boron carbide is an extremely promising material for a variety of applications that require high hardness and good wear resistance. However, due to the very high sintering temperatures which are required for B 4C densification, wide spread use of that is limited. Various solutions have been studied to modifying densification behavior of B 4C. Pressureless sintering in the presence of different additives has been tried by researchers. The effect of additives such as TiB II, SiC, Al, B, ZrO II, talc and Si have been evaluated. It was shown that the densification and mechanical properties may be improved with sintering aids. The Effects of phenolic resin additive on the microstructure and mechanical properties of B 4C were explained in this study. Experimental composition was batched corresponding from 0 to 10 wt% of the additive. All samples were sintered for 60 minutes at 2150°C. The heating and cooling rates were 10°C/min for all samples. It was found that below 7.5 wt% of phenolic resin additive, the density increased with additive increasing and above that, decreased by phenolic resin addition. Mechanical properties such as fracture toughness, strength and hardness increased as a result of densification enhancement.

  11. Structural modifications induced by ion irradiation and temperature in boron carbide B4C

    NASA Astrophysics Data System (ADS)

    Victor, G.; Pipon, Y.; Bérerd, N.; Toulhoat, N.; Moncoffre, N.; Djourelov, N.; Miro, S.; Baillet, J.; Pradeilles, N.; Rapaud, O.; Maître, A.; Gosset, D.

    2015-12-01

    Already used as neutron absorber in the current French nuclear reactors, boron carbide (B4C) is also considered in the future Sodium Fast Reactors of the next generation (Gen IV). Due to severe irradiation conditions occurring in these reactors, it is of primary importance that this material presents a high structural resistance under irradiation, both in the ballistic and electronic damage regimes. Previous works have shown an important structural resistance of boron carbide even at high neutron fluences. Nevertheless, the structural modification mechanisms due to irradiation are not well understood. Therefore the aim of this paper is to study structural modifications induced in B4C samples in different damage regimes. The boron carbide pellets were shaped and sintered by using spark plasma sintering method. They were then irradiated in several conditions at room temperature or 800 °C, either by favoring the creation of ballistic damage (between 1 and 3 dpa), or by favoring the electronic excitations using 100 MeV swift iodine ions (Se ≈ 15 keV/nm). Ex situ micro-Raman spectroscopy and Doppler broadening of annihilation radiation technique with variable energy slow positrons were coupled to follow the evolution of the B4C structure under irradiation.

  12. The interaction between the hepatitis C proteins NS4B and NS5A is involved in viral replication.

    PubMed

    David, Naama; Yaffe, Yakey; Hagoel, Lior; Elazar, Menashe; Glenn, Jeffrey S; Hirschberg, Koret; Sklan, Ella H

    2015-01-15

    Hepatitis C virus (HCV) replicates in membrane associated, highly ordered replication complexes (RCs). These complexes include viral and host proteins necessary for viral RNA genome replication. The interaction network among viral and host proteins underlying the formation of these RCs is yet to be thoroughly characterized. Here, we investigated the association between NS4B and NS5A, two critical RC components. We characterized the interaction between these proteins using fluorescence resonance energy transfer and a mammalian two-hybrid system. Specific tryptophan residues within the C-terminal domain (CTD) of NS4B were shown to mediate this interaction. Domain I of NS5A, was sufficient to mediate its interaction with NS4B. Mutations in the NS4B CTD tryptophan residues abolished viral replication. Moreover, one of these mutations also affected NS5A hyperphosphorylation. These findings provide new insights into the importance of the NS4B-NS5A interaction and serve as a starting point for studying the complex interactions between the replicase subunits.

  13. UBE4B protein couples ubiquitination and sorting machineries to enable epidermal growth factor receptor (EGFR) degradation.

    PubMed

    Sirisaengtaksin, Natalie; Gireud, Monica; Yan, Qing; Kubota, Yoshihisa; Meza, Denisse; Waymire, Jack C; Zage, Peter E; Bean, Andrew J

    2014-01-31

    The signaling of plasma membrane proteins is tuned by internalization and sorting in the endocytic pathway prior to recycling or degradation in lysosomes. Ubiquitin modification allows recognition and association of cargo with endosomally associated protein complexes, enabling sorting of proteins to be degraded from those to be recycled. The mechanism that provides coordination between the cellular machineries that mediate ubiquitination and endosomal sorting is unknown. We report that the ubiquitin ligase UBE4B is recruited to endosomes in response to epidermal growth factor receptor (EGFR) activation by binding to Hrs, a key component of endosomal sorting complex required for transport (ESCRT) 0. We identify the EGFR as a substrate for UBE4B, establish UBE4B as a regulator of EGFR degradation, and describe a mechanism by which UBE4B regulates endosomal sorting, affecting cellular levels of the EGFR and its downstream signaling. We propose a model in which the coordinated action of UBE4B, ESCRT-0, and the deubiquitinating enzyme USP8 enable the endosomal sorting and lysosomal degradation of the EGFR.

  14. The caspase-3 cleavage product of the plasma membrane Ca2+-ATPase 4b is activated and appropriately targeted.

    PubMed

    Pászty, Katalin; Antalffy, Géza; Penheiter, Alan R; Homolya, László; Padányi, Rita; Iliás, Attila; Filoteo, Adelaida G; Penniston, John T; Enyedi, Agnes

    2005-11-01

    The calmodulin-activated transporter hPMCA4 (human plasma membrane Ca2+-ATPase isoform 4) is a target for cleavage by caspase-3 during apoptosis. We have demonstrated that caspase-3 generates a 120 kDa fragment of this pump which lacks the complete autoinhibitory sequence [Paszty, Verma, Padanyi, Filoteo, Penniston and Enyedi (2002) J. Biol. Chem. 277, 6822-6829]. In the present study we analysed further the characteristics of the fragment of hPMCA4b produced by caspase-3. We did this by overexpressing the caspase-3 cleavage product of hPMCA4b in COS-7 and MDCKII (Madin-Darby canine kidney II) cells. This technique made it possible to clearly define the properties of this fragment, and we showed that it is constitutively active, as it forms a phosphoenzyme intermediate and has high Ca2+ transport activity in the absence of calmodulin. When this fragment of hPMCA4b was stably expressed in MDCKII cell clones, it was targeted without degradation to the basolateral plasma membrane. In summary, our studies emphasize that the caspase-3 cleavage product of hPMCA4b is constitutively active, and that the C-terminus is not required for proper targeting of hPMCA4b to the plasma membrane. Also, for the first time, we have generated cell clones that stably express a constitutively active PMCA.

  15. Newly isolated Penicillium oxalicum A592-4B secretes enzymes that degrade milled rice straw with high efficiency.

    PubMed

    Aoyama, Akihisa; Kurane, Ryuichiro; Matsuura, Akira; Nagai, Kazuo

    2015-01-01

    An enzyme producing micro-organism, which can directly saccharify rice straw that has only been crushed without undergoing the current acid or alkaline pretreatment, was found. From the homology with the ITS, 28S rDNA sequence, the strain named A592-4B was identified as Penicillium oxalicum. Activities of the A592-4B enzymes and commercial enzyme preparations were compared by Novozymes Cellic CTec2 and Genencore GC220. In the present experimental condition, activity of A592-4B enzymes was 2.6 times higher than that of CTec2 for degrading milled rice straw. Furthermore, even when a quarter amount of A592-4B enzyme was applied to the rice straw, the conversion rate was still higher than that by CTec2. By utilizing A592-4B enzymes, improved lignocellulose degradation yields can be achieved without pre-treatment of the substrates; thus, contributing to cost reduction as well as reducing environmental burden.

  16. Systems Biology Reveals NS4B-Cyclophilin A Interaction: A New Target to Inhibit YFV Replication.

    PubMed

    Vidotto, Alessandra; Morais, Ana T S; Ribeiro, Milene R; Pacca, Carolina C; Terzian, Ana C B; Gil, Laura H V G; Mohana-Borges, Ronaldo; Gallay, Philippe; Nogueira, Mauricio L

    2017-04-07

    Yellow fever virus (YFV) replication is highly dependent on host cell factors. YFV NS4B is reported to be involved in viral replication and immune evasion. Here interactions between NS4B and human proteins were determined using a GST pull-down assay and analyzed using 1-DE and LC-MS/MS. We present a total of 207 proteins confirmed using Scaffold 3 Software. Cyclophilin A (CypA), a protein that has been shown to be necessary for the positive regulation of flavivirus replication, was identified as a possible NS4B partner. 59 proteins were found to be significantly increased when compared with a negative control, and CypA exhibited the greatest difference, with a 22-fold change. Fisher's exact test was significant for 58 proteins, and the p value of CypA was the most significant (0.000000019). The Ingenuity Systems software identified 16 pathways, and this analysis indicated sirolimus, an mTOR pathway inhibitor, as a potential inhibitor of CypA. Immunofluorescence and viral plaque assays showed a significant reduction in YFV replication using sirolimus and cyclosporine A (CsA) as inhibitors. Furthermore, YFV replication was strongly inhibited in cells treated with both inhibitors using reporter BHK-21-rep-YFV17D-LucNeoIres cells. Taken together, these data suggest that CypA-NS4B interaction regulates YFV replication. Finally, we present the first evidence that YFV inhibition may depend on NS4B-CypA interaction.

  17. AMPK antagonizes hepatic glucagon-stimulated cyclic AMP signalling via phosphorylation-induced activation of cyclic nucleotide phosphodiesterase 4B

    PubMed Central

    Johanns, M.; Lai, Y.-C.; Hsu, M.-F.; Jacobs, R.; Vertommen, D.; Van Sande, J.; Dumont, J. E.; Woods, A.; Carling, D.; Hue, L.; Viollet, B.; Foretz, M; Rider, M H

    2016-01-01

    Biguanides such as metformin have previously been shown to antagonize hepatic glucagon-stimulated cyclic AMP (cAMP) signalling independently of AMP-activated protein kinase (AMPK) via direct inhibition of adenylate cyclase by AMP. Here we show that incubation of hepatocytes with the small-molecule AMPK activator 991 decreases glucagon-stimulated cAMP accumulation, cAMP-dependent protein kinase (PKA) activity and downstream PKA target phosphorylation. Moreover, incubation of hepatocytes with 991 increases the Vmax of cyclic nucleotide phosphodiesterase 4B (PDE4B) without affecting intracellular adenine nucleotide concentrations. The effects of 991 to decrease glucagon-stimulated cAMP concentrations and activate PDE4B are lost in hepatocytes deleted for both catalytic subunits of AMPK. PDE4B is phosphorylated by AMPK at three sites, and by site-directed mutagenesis, Ser304 phosphorylation is important for activation. In conclusion, we provide a new mechanism by which AMPK antagonizes hepatic glucagon signalling via phosphorylation-induced PDE4B activation. PMID:26952277

  18. Coordinated regulation of the ESCRT-III component CHMP4C by the chromosomal passenger complex and centralspindlin during cytokinesis

    PubMed Central

    Capalbo, Luisa; Mela, Ioanna; Abad, Maria Alba; Jeyaprakash, A. Arockia; Edwardson, J. Michael

    2016-01-01

    The chromosomal passenger complex (CPC)—composed of Aurora B kinase, Borealin, Survivin and INCENP—surveys the fidelity of genome segregation throughout cell division. The CPC has been proposed to prevent polyploidy by controlling the final separation (known as abscission) of the two daughter cells via regulation of the ESCRT-III CHMP4C component. The molecular details are, however, still unclear. Using atomic force microscopy, we show that CHMP4C binds to and remodels membranes in vitro. Borealin prevents the association of CHMP4C with membranes, whereas Aurora B interferes with CHMP4C's membrane remodelling activity. Moreover, we show that CHMP4C phosphorylation is not required for its assembly into spiral filaments at the abscission site and that two distinctly localized pools of phosphorylated CHMP4C exist during cytokinesis. We also characterized the CHMP4C interactome in telophase cells and show that the centralspindlin complex associates preferentially with unphosphorylated CHMP4C in cytokinesis. Our findings indicate that gradual dephosphorylation of CHMP4C triggers a ‘relay’ mechanism between the CPC and centralspindlin that regulates the timely distribution and activation of CHMP4C for the execution of abscission. PMID:27784789

  19. Thieno[3,4-b]thiophene-Based Novel Small-Molecule Optoelectronic Materials.

    PubMed

    Zhang, Cheng; Zhu, Xiaozhang

    2017-04-04

    Because of the tailorable photoelectric properties derived from judicious molecular design and large-area and low-temperature processability especially on flexible substrates, design and synthesis of new organic π-functional materials is always a central topic in the field of organic optoelectronics, which siginificantly contributed to the development of high-performance optoelectronic devices such as organic photovoltaics (OPVs), organic field-effect transistors (OFETs), and organic light-emitting diodes (OLEDs). Compared with polymers, small molecules with well-defined molecular structures benefit the establishment of structure-property relationships, which may provide valuable guidelines for the design of new optoelectronic materials to further promote the device performance. New building blocks are essential for the construction of optoelectronic materials. As is well recognized, thiophene-based functional materials have played an indispensable role in the development of organic optoelectronics. Compared with six-membered benzene, five-membered thiophene shows weaker aromaticity and lower steric hindrance and may provide extra sulfur-sulfur interactions in solid state. Among various thiophene building blocks, thieno[3,4-b]thiophene (TbT) is an asymmetric fused bithiophene containing four functionalization positions, in which the proaromatic thiophene can effectively stabilize the quinoidal resonance of the aromatic thiophene. Thus, TbT exhibits a unique characteristic of quinoid-resonance effect that is powerful to modulate electronic structures. Although the application of TbT in polymer donor materials represented by PTB-7 has achieved a great success, its application in small-molecule optoelectronic materials is almost an untouched field. In this Account, we summerize the rational design of a series of TbT-based small-molecule optoelectronic materials designed and optimized by quinoid-resonance effect, regiochemistry, and side-chain engineering and

  20. Investigation of the process chain leading to the development of convection during COP IOP 4b

    NASA Astrophysics Data System (ADS)

    Bauer, H.-S.; Schwitalla, T.; Aoshima, F.; Behrendt, A.; Wulfmeyer, V.

    2012-04-01

    The COPS IOP 4b took place from June 20th to June 21st 2007. It was characterized by widespread convection in the COPS domain. The development was steered by a strong low pressure system southwest of the British Isles. On its eastern side warm and moist subtropical air was directed to central Europe. First convection was triggered over the Vosges Mountains around noon on the 20th of June long before the front approached the COPS region. After a calm early afternoon, severe convection was triggered in wide regions of the COPS region in the evening and moved eastwards to Bavaria during the night to the 21st of June. In contrast to other IOPs, the situation was not captured correctly by most of the involved prediction models, no matter whether they were operated with or without sophisticated data assimilation. Aim of this presentation is to unravel the mechanisms responsible for the triggering of convection and to understand the processes preparing the atmosphere for the development of severe convection during the afternoon and night. For this purpose, many different data sets will be investigated ranging from the high resolution Vienna Enhanced Resolution Analysis (VERA), high resolution radar and satellite images and composites to soundings and data as well as retrieved products from the instruments at the COPS supersites. First impression is that the complicated low-level wind field is the major driver for the preparation of the atmosphere and therefore for the development of convection during the day. The inaccuracies in representing the low level wind field are also expected to be the major reason for the failure of the models to correctly predict the situation.

  1. Skin Involvement and Breast Cancer: Are T4B Lesions of All Sizes Created Equal?

    PubMed Central

    Silverman, Diana; Ruth, Karen; Sigurdson, Elin R.; Egleston, Brian L.; Goldstein, Lori J.; Wong, Yu-Ning; Boraas, Marcia; Bleicher, Richard J.

    2014-01-01

    Background Nonmetastatic non-inflammatory invasive breast cancers having skin involvement (SI) are classified as T4b, regardless of size. This study evaluated disease specific survival (DSS) to determine whether size should be considered for these lesions, rather than grouping them all into Stage III. Study Design Surveillance Epidemiology and End Results data linked to Medicare claims were reviewed. SI and nonSI tumors were reclassified using AJCC 7th Edition groupings using tumor size and nodal involvement alone without considering SI (neostage). DSS was adjusted for demographics, histology and treatment using competing risk methods with propensity score-based weighting and bootstrap standard errors. Results Among 924 SI patients diagnosed between 1992 and 2005, tumors were 0.1–2.0, 2.1–5.0, and >5.0 cm in 11.6%, 51.1%, and 37.3% of cases, respectively. There were no nodal metastases in 22.3%, 1–3 positive nodes in 31.7%, 4–9 positive in 28.6% and ≥10 positive in 17.4% of cases. For SI patients, adjusted 5-year DSS was 95.8% [95%CI: 95.6–96.0] for neostage I, declining progressively to 36.4% [95%CI: 33.8–39.2] for neostage IIIC patients. Adjusted 5-year DSS for SI and nonSI tumors (n=66,185) was similar for neostage I, IIA, and IIB, and markedly lower for IIIA and IIIC. Adjusted DSS for SI IIIA was similar to nonSI IIIC. Conclusions Noninflammatory SI breast cancers have widely varied DSS that differs by tumor size and nodal involvement, and therefore should not all be stage III. SI should be subordinate to T and N groupings to classify SI with nonSI lesions having similar prognoses. PMID:25026875

  2. Preparation and characterization of B4C coatings for advanced research light sources

    PubMed Central

    Störmer, Michael; Siewert, Frank; Sinn, Harald

    2016-01-01

    X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B4C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30–60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B4C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B4C layers are discussed according to thickness uniformity, density, microroughness and thermal stability. The variation of layer thickness in the tangential and sagittal directions was investigated in order to estimate the achieved level of uniformity over the whole deposition area, which is

  3. Preparation and characterization of B4C coatings for advanced research light sources.

    PubMed

    Störmer, Michael; Siewert, Frank; Sinn, Harald

    2016-01-01

    X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B4C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30-60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B4C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B4C layers are discussed according to thickness uniformity, density, microroughness and thermal stability. The variation of layer thickness in the tangential and sagittal directions was investigated in order to estimate the achieved level of uniformity over the whole deposition area, which is considerably

  4. UBE4B Levels Are Correlated with Clinical Outcomes in Neuroblastoma Patients and with Altered Neuroblastoma Cell Proliferation and Sensitivity to EGFR Inhibitors

    PubMed Central

    Zage, Peter E.; Sirisaengtaksin, Natalie; Liu, Yin; Gireud, Monica; Brown, Brandon S.; Palla, Shana; Richards, Kristen N.; Hughes, Dennis P.M.; Bean, Andrew J.

    2012-01-01

    Background The UBE4B gene, located on chromosome 1p36, encodes a ubiquitin ligase that interacts with Hrs, a protein involved in EGFR trafficking, suggesting a link between EGFR trafficking and neuroblastoma pathogenesis. We have analyzed the roles of UBE4B in the outcomes of neuroblastoma patients and in neuroblastoma tumor cell proliferation, EGFR trafficking, and response to EGFR inhibition. Methods We examined the association of UBE4B expression with neuroblastoma patient survival using available microarray datasets. We measured UBE4B and EGFR protein levels in patient tumor samples and EGFR degradation rates in neuroblastoma cell lines and analyzed the effects of UBE4B on neuroblastoma tumor cell growth. The effects of the EGFR inhibitor cetuximab were examined in neuroblastoma cells expressing wild-type and mutant UBE4B. Results Low UBE4B gene expression is associated with poor outcomes in patients with neuroblastoma. UBE4B overexpression reduced neuroblastoma tumor cell proliferation, and UBE4B expression was inversely related to EGFR expression in patient tumor samples. EGFR degradation rates correlated with cellular UBE4B levels. Enhanced expression of catalytically active UBE4B resulted in reduced sensitivity to EGFR inhibition. Conclusions We have demonstrated associations between UBE4B expression and neuroblastoma patient outcomes and between UBE4B and EGFR expression in neuroblastoma tumor samples. Moreover, levels of UBE4B influenced neuroblastoma tumor cell proliferation, EGFR degradation, and response to EGFR inhibition. These results suggest UBE4B-mediated GFR trafficking may contribute to the poor prognosis of neuroblastoma tumors with 1p36 deletions, and that UBE4B expression may be a marker that can predict responses of neuroblastoma tumors to treatment. PMID:22990745

  5. Genome sequence and description of the heavy metal tolerant bacterium Lysinibacillus sphaericus strain OT4b.31

    PubMed Central

    Peña-Montenegro, Tito David; Dussán, Jenny

    2013-01-01

    Lysinibacillus sphaericus strain OT4b.31 is a native Colombian strain having no larvicidal activity against Culex quinquefasciatus and is widely applied in the bioremediation of heavy-metal polluted environments. Strain OT4b.31 was placed between DNA homology groups III and IV. By gap-filling and alignment steps, we propose a 4,096,672 bp chromosomal scaffold. The whole genome (consisting of 4,856,302 bp long, 94 contigs and 4,846 predicted protein-coding sequences) revealed differences in comparison to the L. sphaericus C3-41 genome, such as syntenial relationships, prophages and putative mosquitocidal toxins. Sphaericolysin B354, the coleopteran toxin Sip1A and heavy metal resistance clusters from nik, ars, czc, cop, chr, czr and cad operons were identified. Lysinibacillus sphaericus OT4b.31 has applications not only in bioremediation efforts, but also in the biological control of agricultural pests. PMID:24501644

  6. Local Outbreak of Listeria monocytogenes Serotype 4b Sequence Type 6 Due to Contaminated Meat Pâté.

    PubMed

    Althaus, Denise; Jermini, Marco; Giannini, Petra; Martinetti, Gladys; Reinholz, Danuta; Nüesch-Inderbinen, Magdalena; Lehner, Angelika; Stephan, Roger

    2017-04-01

    In January and February 2016, five cases of confirmed and two cases of probable infection due to Listeria monocytogenes serotype 4b, sequence type (ST) 6 belonging to a single pulsed-field gel electrophoresis pulsotype pattern were registered in a region of southern Switzerland. L. monocytogenes was detected in blood samples (four cases) and pleural fluid (one case). Furthermore, L. monocytogenes 4b ST6 was detected in a stool sample of an asymptomatic person exposed to a common food. Forthwith, the food safety authority and a local gourmet meat producer reported L. monocytogenes contamination of meat pâté. Analysis of further food and environmental samples from the premises of the producer yielded isolates matching the clinical strains and confirmed the presence of L. monocytogenes 4b ST6 in the mincing machine as the cause of the food contamination.

  7. (4aS,4bR,7R,10aS)-3,7-Dimethyl-10a-(propan-2-yl)-1,4,4a,4b,5,6,7,8,10,10a-deca­hydro­phenanthrene-1,4-dione

    PubMed Central

    Caracelli, Ignez; Zukerman-Schpector, Julio; Machado, André T. Lousada; Brocksom, Timothy J.; Ferreira, M. Lúcia; Tiekink, Edward R. T.

    2011-01-01

    In the title compound, C19H26O2, the A ring adopts a chair conformation, whereas the B and C rings both adopt distorted half-chair conformations with the quaternary C atom common to both rings lying 0.577 (3) and 0.648 (3) Å out of the approximate plane defined by the remaining five C atoms (r.m.s. deviations = 0.1386 and 0.1156 Å) for the B and C rings, respectively. Mol­ecules are assembled in the crystal through C—H⋯O inter­actions involving both carbonyl O atoms, which lead to supra­molecular chains aligned along the b axis. PMID:22199712

  8. Upregulation of LAPTM4B-35 promotes malignant transformation and tumorigenesis in L02 human liver cell line.

    PubMed

    Li, Li; Shan, Yi; Yang, Hua; Zhang, Sha; Lin, Ming; Zhu, Ping; Chen, Xin-Yu; Yi, Jing; McNutt, Michael A; Shao, Gen-Ze; Zhou, Rou-Li

    2011-07-01

    Hepatocellular carcinoma (HCC) is one of the most frequent malignant neoplasms worldwide and is the second leading cause of cancer death in China. We have previously demonstrated that LAPTM4B-35, encoded by lysosomal protein transmembrane 4 beta gene, is overexpressed in over 80% of HCCs and is a novel-independent prognostic factor for metastasis, recurrence, and postoperative survival in HCC. In this study, we investigated the role of LAPTM4B-35 in malignant transformation and tumorigenesis using L02 cells, a cell line originated from human normal liver cells. Our data show that replication-deficient adenovirus vector-mediated upregulation of LAPTM4B-35 promotes anchorage-independent proliferation and resistance to adriamycin-induced apoptosis. Study of the underlying mechanisms demonstrated alterations of molecular events involved in these processes, which included the activation of phosphoinositide 3-kinases (PI3K)/serine/threonine protein kinase B (PKB/AKT)/bcl-xL/bcl-2-associated death promoter homolog (Bad) signaling pathway, inhibition of caspase-3 activation, upregulation of Bcl-2, and downregulation of Bax. In addition, upregulation of LAPTM4B-35 in L02 cells resulted in tumorigenesis in 100% (6/6) of inoculated nude mice and accelerated the death of mice with xenografts in vivo. In conclusion, LAPTM4B-35 promotes malignant transformation and tumorigenesis in human liver L02 cell line through promotion of deregulated proliferation and inhibition of apoptosis. These findings suggest that overexpression of LAPTM4B-35 may play a critical role in hepatocarcinogenesis and therefore, may be a therapeutic target for HCC.

  9. Pressure effect on structural, elastic, and thermodynamic properties of tetragonal B{sub 4}C{sub 4}

    SciTech Connect

    Zheng, Baobing; Zhang, Meiguang; Luo, Hong-Gang

    2015-03-15

    The compressibility, elastic anisotropy, and thermodynamic properties of the recently proposed tetragonal B{sub 4}C{sub 4} (t-B{sub 4}C{sub 4}) are investigated under high temperature and high pressure by using of first-principles calculations method. The elastic constants, bulk modulus, shear modulus, Young’s modulus, Vickers hardness, Pugh’s modulus ratio, and Poisson’s ratio for t-B{sub 4}C{sub 4} under various pressures are systematically explored, the obtained results indicate that t-B{sub 4}C{sub 4} is a stiffer material. The elastic anisotropies of t-B{sub 4}C{sub 4} are discussed in detail under pressure from 0 GPa to 100 GPa. The thermodynamic properties of t-B{sub 4}C{sub 4}, such as Debye temperature, heat capacity, and thermal expansion coefficient are investigated by the quasi-harmonic Debye model.

  10. INPP4B-mediated tumor resistance is associated with modulation of glucose metabolism via hexokinase 2 regulation in laryngeal cancer cells

    SciTech Connect

    Min, Joong Won; Kim, Kwang Il; Kim, Hyun-Ah; Kim, Eun-Kyu; Noh, Woo Chul; Jeon, Hong Bae; Cho, Dong-Hyung; Oh, Jeong Su; Park, In-Chul; Hwang, Sang-Gu; Kim, Jae-Sung

    2013-10-11

    Highlights: •HIF-1α-regulated INPP4B enhances glycolysis. •INPP4B regulates aerobic glycolysis by inducing HK2 via Akt-mTOR pathway. •Blockage of INPP4B and HK2 sensitizes radioresistant laryngeal cancer cells to radiation and anticancer drug. •INPP4B is associated with HK2 in human laryngeal cancer tissues. -- Abstract: Inositol polyphosphate 4-phosphatase type II (INPP4B) was recently identified as a tumor resistance factor in laryngeal cancer cells. Herein, we show that INPP4B-mediated resistance is associated with increased glycolytic phenotype. INPP4B expression was induced by hypoxia and irradiation. Intriguingly, overexpression of INPP4B enhanced aerobic glycolysis. Of the glycolysis-regulatory genes, hexokinase 2 (HK2) was mainly regulated by INPP4B and this regulation was mediated through the Akt-mTOR pathway. Notably, codepletion of INPP4B and HK2 markedly sensitized radioresistant laryngeal cancer cells to irradiation or anticancer drug. Moreover, INPP4B was significantly associated with HK2 in human laryngeal cancer tissues. Therefore, these results suggest that INPP4B modulates aerobic glycolysis via HK2 regulation in radioresistant laryngeal cancer cells.

  11. Escape Mutations in NS4B Render Dengue Virus Insensitive to the Antiviral Activity of the Paracetamol Metabolite AM404

    PubMed Central

    van Cleef, Koen W. R.; Overheul, Gijs J.; Thomassen, Michael C.; Marjakangas, Jenni M.

    2016-01-01

    Despite the enormous disease burden associated with dengue virus infections, a licensed antiviral drug is lacking. Here, we show that the paracetamol (acetaminophen) metabolite AM404 inhibits dengue virus replication. Moreover, we find that mutations in NS4B that were previously found to confer resistance to the antiviral compounds NITD-618 and SDM25N also render dengue virus insensitive to AM404. Our work provides further support for NS4B as a direct or indirect target for antiviral drug development. PMID:26856827

  12. Kepler-4b: A Hot Neptune-Like Planet of a G0 Star Near Main-Sequence Turnoff

    DTIC Science & Technology

    2010-04-20

    70 80 90. 100 Planetary Mass (Earth Masses) 1 2 3 4 5 6 7 R ad iu s (E ar th R ad ii) Kepler-4b Uranus Neptune GJ 436b Baraffe Z=0.5, NI, 7Gyr HAT...have masses and radii equal to or larger than those of Neptune and Uranus . The most important differences between the three exoplanets are their host...in Neptune or Uranus ). Nevertheless, we can state with a measure of confidence that there are no possible interior models for Kepler-4b with no H/He

  13. The Development of a Degree 360 Expansion of the Dynamic Ocean Topography of the POCM_4B Global Circulation Model

    NASA Technical Reports Server (NTRS)

    Rapp, Richard H.

    1998-01-01

    This paper documents the development of a degree 360 expansion of the dynamic ocean topography (DOT) of the POCM_4B ocean circulation model. The principles and software used that led to the final model are described. A key principle was the development of interpolated DOT values into land areas to avoid discontinuities at or near the land/ocean interface. The power spectrum of the POCM_4B is also presented with comparisons made between orthonormal (ON) and spherical harmonic magnitudes to degree 24. A merged file of ON and SH computed degree variances is proposed for applications where the DOT power spectrum from low to high (360) degrees is needed.

  14. Synthesis of Substituted 2,3,5,6-tetraarylbenzo(1,2-b:5,4-b')difurans

    NASA Technical Reports Server (NTRS)

    Abdul-Aziz, Mahmoud; Auping, Judith V.; Meador, Michael A.

    1995-01-01

    A series of substituted 2,3,5,6-tetraarylbenzo(l,2-b:5,4-b')difurans 1 was synthesized. This synthesis is based upon the photocyclization of 2,5-dibenzoylresorcinol dibenzyl ethers to the corresponding tetrahydrobenzo(1,2-b:5,4-b')difurans. Treatment of the photoproducts with methanesulfonyl chloride in pyridine afforded 1 in overall yields ranging from 30-72%. A number of these compounds have high fluorescence quantum yields (of phi(sub f) = 0.76-0.90), and their fluorescence spectra exhibit large solvatochromic shifts. These compounds may be suitable for use as fluorescent probes.

  15. Heat shock factor-4 (HSF-4a) is a repressor of HSF-1 mediated transcription.

    PubMed

    Zhang, Y; Frejtag, W; Dai, R; Mivechi, N F

    2001-01-01

    Heat shock transcription factors (HSFs) regulate the expression of heat shock proteins and other molecular chaperones that are involved in cellular processes from higher order assembly to protein degradation and apoptosis. Among the human HSFs, HSF-4 is expressed as at least two splice variants. One isoform (HSF-4b) possesses a transcriptional activation domain, but this region is absent in the other isoform (HSF-4a). We have recently shown that the HSF-4a isoform represses basal transcription from heterologous promoters both in vitro and in vivo. Here we show that HSF-4a and HSF-4b have dramatically different effects on HSF-1-containing nuclear bodies, which form after heat shock. While the expression of HSF-4b colocalizes with nuclear granules, the expression of HSF-4a prevents their formation. In addition, there is a concurrent reduction of HSF-1 in the nucleus, and there is reduction in its DNA binding activity and in HSE-dependent transcription of a reporter gene. To better understand the mechanism by which HSF-4a represses transcription, we inducibly expressed HSF-4a in cells and found that HSF-4a binds to the heat shock element (HSE) during attenuation of the heat shock response. Thus HSF-4a is an active repressor of HSF-1-mediated transcription. This repressor function makes the HSF-4a isoform unique within the HSF family.

  16. On the merging cluster Abell 578 and its central radio galaxy 4C+67.13

    DOE PAGES

    Hagino, K.; Stawarz, Ł.; Siemiginowska, A.; ...

    2015-05-26

    Here we analyze radio, optical, and X-ray data for the peculiar cluster Abell 578. This cluster is not fully relaxed and consists of two merging sub-systems. The brightest cluster galaxy (BCG), CGPG 0719.8+6704, is a pair of interacting ellipticals with projected separation ~10 kpc, the brighter of which hosts the radio source 4C+67.13. The Fanaroff–Riley type-II radio morphology of 4C+67.13 is unusual for central radio galaxies in local Abell clusters. Our new optical spectroscopy revealed that both nuclei of the CGPG 0719.8+6704 pair are active, albeit at low accretion rates corresponding to the Eddington ratiomore » $$\\sim {{10}^{-4}}$$ (for the estimated black hole masses of $$\\sim 3\\times {{10}^{8}}\\;{{M}_{\\odot }}$$ and $$\\sim {{10}^{9}}\\;{{M}_{\\odot }}$$). The gathered X-ray (Chandra) data allowed us to confirm and to quantify robustly the previously noted elongation of the gaseous atmosphere in the dominant sub-cluster, as well as a large spatial offset (~60 kpc projected) between the position of the BCG and the cluster center inferred from the modeling of the X-ray surface brightness distribution. Detailed analysis of the brightness profiles and temperature revealed also that the cluster gas in the vicinity of 4C+67.13 is compressed (by a factor of about ~1.4) and heated (from $$\\simeq 2.0$$ keV up to 2.7 keV), consistent with the presence of a weak shock (Mach number ~1.3) driven by the expanding jet cocoon. As a result, this would then require the jet kinetic power of the order of $$\\sim {{10}^{45}}$$ erg s–1, implying either a very high efficiency of the jet production for the current accretion rate, or a highly modulated jet/accretion activity in the system.« less

  17. On the merging cluster Abell 578 and its central radio galaxy 4C+67.13

    SciTech Connect

    Hagino, K.; Stawarz, Ł.; Siemiginowska, A.; Cheung, C. C.; Kozieł-Wierzbowska, D.; Szostek, A.; Madejski, G.; Harris, D. E.; Simionescu, A.; Takahashi, T.

    2015-05-26

    Here we analyze radio, optical, and X-ray data for the peculiar cluster Abell 578. This cluster is not fully relaxed and consists of two merging sub-systems. The brightest cluster galaxy (BCG), CGPG 0719.8+6704, is a pair of interacting ellipticals with projected separation ~10 kpc, the brighter of which hosts the radio source 4C+67.13. The Fanaroff–Riley type-II radio morphology of 4C+67.13 is unusual for central radio galaxies in local Abell clusters. Our new optical spectroscopy revealed that both nuclei of the CGPG 0719.8+6704 pair are active, albeit at low accretion rates corresponding to the Eddington ratio $\\sim {{10}^{-4}}$ (for the estimated black hole masses of $\\sim 3\\times {{10}^{8}}\\;{{M}_{\\odot }}$ and $\\sim {{10}^{9}}\\;{{M}_{\\odot }}$). The gathered X-ray (Chandra) data allowed us to confirm and to quantify robustly the previously noted elongation of the gaseous atmosphere in the dominant sub-cluster, as well as a large spatial offset (~60 kpc projected) between the position of the BCG and the cluster center inferred from the modeling of the X-ray surface brightness distribution. Detailed analysis of the brightness profiles and temperature revealed also that the cluster gas in the vicinity of 4C+67.13 is compressed (by a factor of about ~1.4) and heated (from $\\simeq 2.0$ keV up to 2.7 keV), consistent with the presence of a weak shock (Mach number ~1.3) driven by the expanding jet cocoon. As a result, this would then require the jet kinetic power of the order of $\\sim {{10}^{45}}$ erg s–1, implying either a very high efficiency of the jet production for the current accretion rate, or a highly modulated jet/accretion activity in the system.

  18. Synthesis and properties of 2'-O,4'-C-ethyleneoxy bridged 5-methyluridine.

    PubMed

    Hari, Yoshiyuki; Morikawa, Tomohiko; Osawa, Takashi; Obika, Satoshi

    2013-07-19

    2'-O,4'-C-Ethyleneoxy bridged 5-methyluridine (EoNA-T), possessing a seven-membered linkage and an anomeric 4'-carbon, was synthesized and introduced into oligonucleotides by using an automated DNA synthesizer. The EoNA-modified oligonucleotides significantly stabilized the duplexes with single-stranded RNA and triplexes with double-stranded DNA relative to the natural oligonucleotide and oligonucleotides modified by another seven-membered bridged 5-methyluridine, 2',4'-BNA(COC)-T. In addition, EoNA-T showed excellent nuclease resistance.

  19. Morphological research on radio loud AGN 4C39.25 using KaVA observations

    NASA Astrophysics Data System (ADS)

    Yoo, Hyemin; Sohn, Bong Won; Yi, Sukyoung; KaVA AGN WG members

    2016-01-01

    4C39.25 (0923+392) is a distant radio loud AGN placed at redshift 0.695. Its kilo-parsec scale jet observed by VLBA(Kollgaard et al. 1990) and parsec scale jet observed by VLBA(Kellermann et al. 1998) are misaligned. This might indicate episodic-jet activity which recently turned on. This object currently shows two stationary compact parsec-scale components:a bright jet component on the east and less luminous core on the west. Also, it is known that there have been superluminal jet components which are flowing from the core toward east, and then merging with the bright jet component (Marscher et al. 1991, Alberdi et al. 2000, Lister et al. 2013). Including the detection of broad emission lines(SDSS), its viewing angle was concluded to be small. However, the jet component being more luminous than the core is abnormal for a source with a small viewing angle. Furthermore, it has young radio galaxy-like properties such as non-variation in total flux(Alberdi et al. 1997, 2000, MOJAVE database) and a high frequency peak in the spectral energy distribution(Orienti et al 2007). In this case, it is more reliable to think that viewing angle of 4C39.25 is large. Korean VLBI Network (KVN) and VLBI Exploration of Radio Astronomy (VERA) Array (KaVA) is a cooperated VLBI system of Korea and Japan which provides high-frequency (23GHz and 43GHz) and high spatial resolution(1.2mas and 0.6mas). Their advantages of multi-wavelength and relatively high S/N ratio relative to its number of baseline allow us to discover the central region and dim structures of 4C39.25. We present results of several epochs observed during 2013 to 2014, focusing on morphological changes of 4C39.25 using KaVA images. According to these results, we were able to find a recently emitted counter-jet component for images of first 6 epochs. Also the counter-jet component propagates along a curved trajectory, and it shows an extreme superluminal motion. This might indicate a necessity of relatively large viewing

  20. Laboratory Spectra of Mixtures of CH4, C2H6, and CH3OH

    NASA Technical Reports Server (NTRS)

    Mastrapa, Rachel; Berry, Matthew T.; Sandford, Scott

    2011-01-01

    Infrared spectroscopy is commonly used as a tool for identifying the composition of objects in the Solar System and beyond. Using laboratory spectra, optical constants can be calculated and used to create model spectra for comparison to spectra obtained from infrared telescopes. In this study, the optical constants of mixtures of simple organics, including CH4, C2H6, and CH3OH were calculated from 15 to 70 K, in the frequency range of 9000-500 cm(sup -1) (1.1-20 micrometers), at a spectral resolution of 1 cm(sup -1).

  1. Inelastic X-ray scattering experiments on B[subscript 4]C under high static pressures

    SciTech Connect

    Kumar, Ravhi S.; Dandekar, Dattatraya; Leithe-Jasper, Andres; Tanaka, Takaho; Xiao, Yuming; Chow, Paul; Nicol, Malcolm F.; Cornelius, Andrew L.

    2010-05-04

    Boron K-edge inelastic X-ray scattering experiments were performed on clean B{sub 4}C and shock impact recovered boron carbide up to 30 GPa and at ambient temperature to understand the pressure induced bonding changes. The spectral features corresponding to the boron site in the interlinking chain remained unchanged up to 30 GPa. The results of our experiments indicate that pressure induces less distortion to the boron sites and the local amorphization observed in the previous reports are due to the rearrangement of carbon atoms under extreme conditions without affecting the boron environment.

  2. Fermi LAT and Swift flare of the FSRQ 4C +40.25

    NASA Astrophysics Data System (ADS)

    Carpenter, Bryce; Ojha, Roopesh; Pivato, Giovanna; Fermi Large Area Telescope Collaboration

    2015-11-01

    The Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope has observed a gamma-ray flare from a source positionally consistent with the flat spectrum radio quasar (FSRQ) 4C +40.25 (also known as B2 1020+40 and 3FGL J1023.1+3952, Acero et al. 2015, ApJS 218, 23) with coordinates RA: 10h 23m 11.5661s, Dec: 39d 48m 15.378s, J2000, (Helmboldt et al. 2007, ApJ, 658, 203) and a redshift of 1.254 (Xu et al. 1994, AJ, 108, 395).

  3. PARTICLE ACCELERATION AND MAGNETIC FIELD AMPLIFICATION IN THE JETS OF 4C74.26

    SciTech Connect

    Araudo, A. T.; Blundell, K. M.; Bell, A. R.

    2015-06-20

    We model the multi-wavelength emission in the southern hotspot of the radio quasar 4C74.26. The synchrotron radio emission is resolved near the shock with the MERLIN radio-interferometer, and the rapid decay of this emission behind the shock is interpreted as the decay of the amplified downstream magnetic field as expected for small scale turbulence. Electrons are accelerated to only 0.3 TeV, consistent with a diffusion coefficient many orders of magnitude greater than in the Bohm regime. If the same diffusion coefficient applies to the protons, their maximum energy is only ∼100 TeV.

  4. Egr-1 regulates irradiation-induced autophagy through Atg4B to promote radioresistance in hepatocellular carcinoma cells

    PubMed Central

    Peng, W-x; Wan, Y-y; Gong, A-h; Ge, L; Jin, J; Xu, M; Wu, C-y

    2017-01-01

    Although hepatocellular carcinoma (HCC) is usually response to radiation therapy, radioresistance is still the major obstacle that limits the efficacy of radiotherapy for HCC patients. Therefore, further investigation of underlying mechanisms in radioresistant HCC cells is warranted. In this study, we determined the effect of early growth response factor (Egr-1) on irradiation-induced autophagy and radioresistance in HCC cell lines SMMC-7721 and HepG2. We showed that autophagy-related gene 4B (Atg4B) is induced by Egr-1 upon ionizing radiation (IR) in HCC cells. Luciferase reporter assays and chromatin immunoprecipitation (ChIP) revealed that Egr-1 binds to the Atg4B promoter to upregulate its expression in HCC cells. Suppression of Egr-1 function by dominant-negative Egr-1 dampens IR-induced autophagy, cell migration, and increases cell sensitivity to radiotherapy. Together, these results suggest that Egr-1 contributes to HCC radioresistance through directly upregulating target gene Atg4B, which may serve as a protective mechanism by preferential activation of the autophagy. PMID:28134935

  5. Near-Zero Thermal Expansion and High Ultraviolet Transparency in a Borate Crystal of Zn4 B6 O13.

    PubMed

    Jiang, Xingxing; Molokeev, Maxim S; Gong, Pifu; Yang, Yi; Wang, Wei; Wang, Shuaihua; Wu, Shaofan; Wang, Yingxia; Huang, Rongjin; Li, Laifeng; Wu, Yicheng; Xing, Xianran; Lin, Zheshuai

    2016-09-01

    Intrinsic isotropic near-zero thermal expansion is discovered in borate crystal Zn4 B6 O13 with high transparency in the ultraviolet region. First-principles calculations demonstrate that the very low thermal expansion originates mainly from the invariability of the solid [B24 O48 ] truncated octahedra that are fixed by the [Zn4 O13 ] clusters in the ZBO structure.

  6. Genetic determinants for cadmium and arsenic resistance among Listeria monocytogenes serotype 4b isolates from sporadic human listeriosis patients

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Listeria monocytogenes serotype 4b from sporadic listeriosis, heavy metal resistance was primarily encountered in certain clonal groups (ECI, ECII, ECIa). All arsenic-resistant isolates harbored the arsenic resistance cassette previously identified in pLI100; ECIa harbored additional arsenic resi...

  7. Increased expression of plasma membrane Ca(2+)ATPase 4b in platelets from hypertensives: a new sign of abnormal thrombopoiesis?

    PubMed

    Dally, Saoussen; Chaabane, Chiraz; Corvazier, Elisabeth; Bredoux, Raymonde; Bobe, Regis; Ftouhi, Bochra; Slimane, Hedia; Raies, Aly; Enouf, Jocelyne

    2007-11-01

    Platelet Ca(2+) homeostasis is controlled by a multi-Ca(2+)ATPase system including two PMCA (plasma membrane Ca(2+)ATPase) and seven SERCA (sarco/endoplasmic reticulum Ca(2+)ATPase) isoforms. Previous studies have shown similar platelet Ca(2+) abnormalities in diabetic and hypertensive patients, including an increase in intracellular [Ca(2+)](I), a possible modulation of PMCA activity and increased PMCA tyrosine phosphorylation. Very recently, we found that platelets from diabetic patients also exhibited increased PMCA4b expression. In the present study we looked for further similarities between diabetic and hypertensive patients. We first confirmed a decrease in Ca(2+)ATPase activity (mean 55 + 7%) in mixed platelet membranes isolated from 10 patients with hypertension compared with those from 10 healthy controls. In addition, the decreased Ca(2+)ATPase activity correlated with the DBP of the different patients, as expected for PMCA activity. Second, we performed a pilot study of six hypertensives to examine their expressions of PMCA and SERCA mRNA and proteins. Like the diabetic patients, 100% of hypertensives were found to present a major increase in PMCA4b expression (mean value of 218 +/- 21%). We thus determined that platelets from diabetic and hypertensive patients showed similar increased PMCA4b isoform. Since increased PMCA4b expression was recently found to be associated with a perturbation of megakaryocytopoiesis, these findings may also point to an abnormality in platelet maturation in hypertension.

  8. 75 FR 40843 - International Conference on Harmonisation; Draft Guidance on Q4B Evaluation and Recommendation of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-14

    ... Q4B Evaluation and Recommendation of Pharmacopoeial Texts for Use in the International Conference on... Pharmacopoeial Texts for Use in the ICH Regions; Annex 13: Bulk Density and Tapped Density of Powders General... General Chapter harmonized text from each of the three pharmacopoeias (United States, European,...

  9. The interaction between the Hepatitis C proteins NS4B and NS5A is involved in viral replication

    PubMed Central

    David, Naama; Yaffe, Yakey; Hagoel, Lior; Elazar, Menashe; Glenn, Jeffrey S.; Hirschberg, Koret; Sklan, Ella H.

    2015-01-01

    Hepatitis C virus (HCV) replicates in membrane associated, highly ordered replication complexes (RCs). These complexes include viral and host proteins necessary for viral RNA genome replication. The interaction network among viral and host proteins underlying the formation of these RCs is yet to be thoroughly characterized. Here, we investigated the association between NS4B and NS5A, two critical RC components. We characterized the interaction between these proteins using fluorescence resonance energy transfer and a mammalian two-hybrid system. Specific tryptophan residues within the C-terminal domain (CTD) of NS4B were shown to mediate this interaction. Domain I of NS5A, was sufficient to mediate its interaction with NS4B. Mutations in the NS4B CTD tryptophan residues abolished viral replication. Moreover, one of these mutations also affected NS5A hyperphosphorylation. These findings provide new insights into the importance of the NS4B–NS5A interaction and serve as a starting point for studying the complex interactions between the replicase subunits. PMID:25462354

  10. Dimeric procyanidins: screening for B1 to B8 and semisynthetic preparation of B3, B4, B6, And B8 from a polymeric procyanidin fraction of white willow bark (Salix alba).

    PubMed

    Esatbeyoglu, Tuba; Wray, Victor; Winterhalter, Peter

    2010-07-14

    Fifty-seven samples have been analyzed with regard to the occurrence of dimeric procyanidins B1-B8 as well as the composition of polymeric procyanidins. Fifty-two samples were found to contain polymeric procyanidins. In most of the samples, (-)-epicatechin was the predominant unit present. In white willow bark (Salix alba), however, large amounts of (+)-catechin (81.0%) were determined by means of phloroglucinolysis. White willow bark has therefore been used for the semisynthetic formation of dimeric procyanidins B3 [(+)-C-4alpha --> 8-(+)-C)], B4 [(+)-C-4alpha --> 8-(-)-EC)], B6 [(+)-C-4alpha --> 6-(+)-C)], and B8 [(+)-C-4alpha --> 6-(-)-EC)]. The reaction mixtures of the semisynthesis were successfully fractionated with high-speed countercurrent chromatography (HSCCC), and dimeric procyanidins B3, B4, B6, and B8 were obtained on a preparative scale.

  11. SiC or B4C-B/low strategic element content composite

    NASA Technical Reports Server (NTRS)

    Petrasek, D. W.

    1982-01-01

    Advancements in materials technologies are needed to provide the aerospace industry with alternate material options in the event of future strategic metal shortages and to optimize performance of engines. Composite materials are promising candidates for such an application. The potential of SiC and B4C-B filament reinforced low strategic element iron-base alloy content composites or use at 760 to 870 C is considered. A limiting factor towards developing this material for high temperature use has been the reaction between the filament and matrix material during fabrication and service which degrades filament strength. A low temperature fabrication process to limit filament/matrix reaction is being developed which involves the use of hollow cathode sputtering to coat the filaments with iron-base alloys of various compositions. An investigation is being conducted to determine the interfacial reaction effects of SiC and B4C-B filaments with iron-base alloys to develop an understanding of filament/matrix alloy compatibility for 760 to 870 C service.

  12. Development of Thick B4C Coatings for the First Wall of W7-X

    NASA Astrophysics Data System (ADS)

    Kötterl, S.; Bolt, H.; Greuner, H.; Huber, A.; Linke, J.; Mayer, M.; Pospieszczyk, A.; Renner, H.; Roth, J.; Schweer, B.; Sergienko, G.; Valenza, D.

    For the actively cooled first wall panels of the W7-X stellarator under construction at Greifswald, Germany, boron carbide (B4C) coatings with a thickness up to 500 μm are being developed as plasma facing surface on the stainless steel component. Different coating technologies (vacuum plasma spray (VPS), atmospherical plasma spray (APS)) are investigated. Characterisation of the coatings comprises metallo"graphic and SEM investigations, impurity determination and measurement of the thermal conductivity, characterisation of the sputtering behaviour and the behaviour under plasma exposure. First in-pile-tests in the tokamak TEXTOR-94 at the Research Centre Juelich have been performed. 10 poloidal limiter elements and 5 test limiters made of copper with a 170 μm thick B4C VPS coating were exposed to plasma discharges with ohmic and additional heating. By varying the limiter positions and plasma density, different loading conditions were imposed. After exposure, the test limiters were removed for further analyses. First results showed the formation of small craters in the coating, probably due to arcing. Although melting occurred within a limited zone around the craters, the coatings did not detach from the substrate or show severe cracking outside the molten area.

  13. Inflation and monopoles in supersymmetric SU(4)c × SU(2)L × SU(2)R

    NASA Astrophysics Data System (ADS)

    Jeannerot, Rachel; Khalil, Shaaban; Lazarides, George; Shafi, Qaisar

    2000-10-01

    We show how hybrid inflation can be successfully realized in a supersymmetric model with gauge group GPS = SU(4)c × SU(2)L × SU(2)R. By including a non-renormalizable superpotential term, we generate an inflationary valley along which GPS is broken to the standard model gauge group. Thus, catastrophic production of the doubly charged magnetic monopoles, which are predicted by the model, cannot occur at the end of inflation. The results of the cosmic background explorer can be reproduced with natural values (of order 10-3) of the relevant coupling constant, and symmetry breaking scale of GPS of the order of 1016 GeV. The spectral index of density perturbations lies between unity and 0.9. Moreover, the μ-term is generated via a Peccei-Quinn symmetry and proton is practically stable. Baryogenesis in the universe takes place via leptogenesis. The low deuterium abundance constraint on the baryon asymmetry, the gravitino limit on the reheat temperature and the requirement of almost maximal νμ-ντ mixing from SUPER-KAMIOKANDE can be simultaneously met with mνμ, mντ and heaviest Dirac neutrino mass determined from the large angle MSW resolution of the solar neutrino problem, the SUPER-KAMIOKANDE results and SU(4)c symmetry respectively.

  14. Nanostructured Fe3O4@C as anode material for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Zeng, Zhipeng; Zhao, Hailei; Wang, Jie; Lv, Pengpeng; Zhang, Tianhou; Xia, Qing

    2014-02-01

    The active particle cracking and electrode pulverization of iron oxide anode material as a result of volume expansion during charge/discharge process cause poor reversibility and significant capacity fading in rechargeable lithium-ion batteries. Here, we demonstrate a facile solvothermal route to immobilize the Fe3O4 particles on the porous active carbon. The present method enables us to obtain nano-porous and mosaic structured Fe3O4@C spheres with an average size of ca. 100 nm. The porous active carbon plays an important role in the improvement of electrochemical properties of Fe3O4. It not only acts as a host for the deposition of Fe3O4 particles, but also provides void spaces for active Fe3O4 to buffer the volume expansion. The good contact between Fe3O4 and active carbon ensures the fast electron/Li-ion transport. As a result, the porous Fe3O4@C shows a high reversible specific capacity of ∼1000 mAh g-1, good cycle stability and excellent rate capability. Therefore, we believe that this composite is a potential candidate for anode material of high-energy lithium-ion battery.

  15. Proteomic analysis of male 4C germ cell proteins involved in mouse meiosis.

    PubMed

    Guo, Xuejiang; Zhang, Ping; Qi, Yujuan; Chen, Wen; Chen, Xiangxiang; Zhou, Zuomin; Sha, Jiahao

    2011-01-01

    Male meiosis is a specialized type of cell division that gives rise to sperm. Errors in this process can result in the generation of aneuploid gametes, which are associated with birth defects and infertility in humans. Until now, there has been a lack of a large-scale identification of proteins involved in male meiosis in mammals. In this study, we report the high-confidence identification of 3625 proteins in mouse male germ cells with 4C DNA content undergoing meiosis I. Of these, 397 were found to be testis specific. Bioinformatics analysis of the proteome led to the identification of 28 proteins known to be essential for male meiosis in mice. We also found 172 proteins that had yeast orthologs known to be essential for meiosis. Chromosome distribution analysis of the proteome showed underrepresentation of the identified proteins on the X chromosome, which may be due to meiotic sex chromosome inactivation. Characterization of the proteome of 4C germ cells from mouse testis provides an inventory of proteins, which is useful for understanding meiosis and the mechanisms of male infertility.

  16. Synthesis and electrochemical performance of nano-metastructured LiFePO4/C cathode material.

    PubMed

    Zhi, Xiaoke; Liang, Guangchuan; Wang, Li; Cui, Junyan; Yang, Limei

    2010-11-01

    The nano-metastructured LiFePO4/C composites were synthesized by carbothermal reduction method using starch gel as carbon source and dispersing media to obtain high tap density LiFePO4 with excellent electrochemical performance. The raw materials were coated by starch gel as compact precursors, which was sintered at 750 degrees C for 8 h to obtain high-density LiFePO4/C composite aggregated with nano-sized particles. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations showed that the primary particles had an average size of about 50-80 nm and the aggregates had a homogeneous particle size distribution of about 400 nm. The asprepared samples had a shortened lithium-ion diffusion length but with higher tap density, thus leading to the excellent electrochemical performance of the cathode materials. Electrochemical results showed that the samples delivered high discharge capacities of 155.6 and 120.7 mAh/g at 0.2C and 5C rates, respectively, with excellent cycling performance.

  17. Processing and characterization of zeta-Ta4C 3-x: A high toughness tantalum carbide

    NASA Astrophysics Data System (ADS)

    Sygnatowicz, Michael M.

    Tantalum carbides are commonly processed by hot-pressing, canned hot-isostatic-pressing, or spark-plasma sintering because of their high melting temperatures and low diffusivities. This study reports processing of dense ζ-Ta4C 3-x by reaction sintering of a Ta and TaC powder mixture (C/Ta atomic ratio = 0.66). ζ-Ta4C3-x is of interest due to its rhombohedral (trigonal) crystal structure that may be characterized as a polytype with both face-centered-cubic (fcc) and hexagonal-close-packed (hcp) Ta stacking sequences interrupted by stacking faults and missing carbon layers. This structure leads to easy cleaving on the basal planes and high fracture toughness. A key step in processing is the hydrogenation of the Ta powder to produce beta-TaH x, a hard and brittle phase that enables efficient comminution during milling and production of small, equiaxed Ta particles that can be packed to high green density with the TaC powder. Studies of phase evolution by quantitative X-ray diffraction during sintering revealed several intermediate reactions: (a) decomposition of beta-TaHx to Ta, (b) diffusion of C from gamma-TaC to Ta leading to the formation of α-Ta2Cy' with the kinetics described by the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation with an exponent, n = 0.5, and an activation energy of 221 kJ/mole, (c) equilibration of α-Ta2Cy' and gamma-TaC 0.78 phases, and (d) formation of ζ-Ta4C2.56 from the equilibrated α-Ta2C and gamma-TaC0.78 phases with the kinetics characterized by a higher JMAK exponent ( n ≈ 3) and higher activation energy (1089 kJ/mole). The microstructure showed evidence of nucleation and growth of the ζ-Ta4C 2.56 phase in both the α-Ta2C and gamma-TaC0.78 parent phases with distinct difference in the morphology due to the different number of variants of the habit plane. A hot-pressed and hot-isostatic-pressed (HIPed) material (C/Ta atomic ratio = 0.66), having formed 95 w% ζ-phase, attained a fracture toughness of 15.6 +/- 0.5 MPa√m and a

  18. KDM4B histone demethylase and G9a regulate expression of vascular adhesion proteins in cerebral microvessels

    PubMed Central

    Choi, Ji-Young; Yoon, Sang-Sun; Kim, Sang-Eun; Ahn Jo, Sangmee

    2017-01-01

    Intercellular adhesion molecule 1 (ICAM1) mediates the adhesion and transmigration of leukocytes across the endothelium, promoting inflammation. We investigated the epigenetic mechanism regulating ICAM1 expression. The pro-inflammatory cytokine TNF-α dramatically increased ICAM1 mRNA and protein levels in human brain microvascular endothelial cells and mouse brain microvessels. Chromatin immunoprecipitation revealed that TNF-α reduced methylation of histone H3 at lysines 9 and 27 (H3K9 and H3K27), well-known residues involved in gene suppression. Inhibition of G9a and EZH2, histone methyltransferases responsible for methylation at H3K9 and H3K27, respectively as well as G9a overexpression demonstrated the involvement of G9a in TNF-α-induced ICAM1 expression and leukocyte adhesion and transmigration. A specific role for KDM4B, a histone demethylase targeting H3K9me2, in TNF-α-induced ICAM1 upregulation was validated with siRNA. Moreover, treating mice with a KDM4 inhibitor ML324 blocked TNF-α-mediated neutrophil adhesion. Similarly, TNF-α-induced VCAM1 expression was suppressed by G9a overexpression and KDM4B knockdown. Collectively, we demonstrated that modification of H3K9me2 by G9a and KDM4B regulates expression of vascular adhesion molecules, and that depletion of these proteins or KDM4B reduces inflammation-induced leukocyte extravasation. Thus, blocking ICAM1 or KDM4B could offer a novel therapeutic opportunity treating brain diseases. PMID:28327608

  19. Interfacial properties and electron structure of Al/B4C interface: A first-principles study

    NASA Astrophysics Data System (ADS)

    Xian, Yajiang; Qiu, Ruizhi; Wang, Xin; Zhang, Pengcheng

    2016-09-01

    This research aims at investigating the structural, mechanical and electronic properties of the Al (111)/B4C (0001) interface by first-principles calculations. This model geometry Al (111)/B4C (0001) is chosen because the close-packed planes of Al and B4C have the (111) and (0001) orientation, respectively, and the lattice mismatch is only ∼2.1%. Among four B4C (0001) surfaces with different terminations, our calculation of surface free energies predicted that C-terminated B4C (0001) surface is the most stable one. Relaxed atomic geometries, the work of adhesion and interfacial free energies were calculated for three C-terminated B4C (0001)/Al (111) interfaces with different stacking sequences (top-site, hollow-site, and bridge-site). Results reveal that the relaxed top-site (hollow-site-like) Al/B4C interface has the best adhesion force and also be the most stable. The interfacial electron structure including charge density difference, Bader charge and density of states (DOS) is analyzed to determine the nature of metal/carbide bonding and we find the formation of Alsbnd C bond and possibly the formation of Al4C3 in the interface.

  20. Formation of Al/B4C Surface Nano-composite Layers on 7075 Al Alloy Employing Friction Stir Processing

    NASA Astrophysics Data System (ADS)

    Kashani-Bozorg, S. F.; Jazayeri, K.

    2009-06-01

    Al/B4C surface nano-composite layers was achieved on commercial 7075 Al substrate employing friction stir processing technique. Agglomeration of B4C particles was occurred after a single pass. The dispersion of B4C particles was found to be affected by the number of FSP passes. A distribution of nano-size B4C particle was achieved after four passes. Moreover, the increasing in number of FSP passes causes a decreasing in matrix grain size of the surface nano-composite layer. The micro hardness of the surface nano-composite layer improves by almost two times as compared to that of the as-received substrate; this is attributed to the finer matrix grains and dispersion of nano-sized B4C particles.

  1. Multifrequency studies of the peculiar quasar 4C +21.35 during the 2010 flaring activity

    SciTech Connect

    Ackermann, M.; Buehler, R.; Ajello, M.; Allafort, A.; Caliandro, G. A.; Cameron, R. A.; Antolini, E.; Bonamente, E.; Cecchi, C.; Barbiellini, G.; Bastieri, D.; Buson, S.; Bellazzini, R.; Bregeon, J.; Bissaldi, E.; Brigida, M.; Bruel, P.; Cavazzuti, E.; Chaves, R. C. G. E-mail: justin.finke@nrl.navy.mil E-mail: tterzic@uniri.hr [Laboratoire AIM, CEA-IRFU Collaboration: Fermi Large Area Telescope Collaboration; MAGIC Collaboration; and others

    2014-05-10

    The discovery of rapidly variable Very High Energy (VHE; E > 100 GeV) γ-ray emission from 4C +21.35 (PKS 1222+216) by MAGIC on 2010 June 17, triggered by the high activity detected by the Fermi Large Area Telescope (LAT) in high energy (HE; E > 100 MeV) γ-rays, poses intriguing questions on the location of the γ-ray emitting region in this flat spectrum radio quasar. We present multifrequency data of 4C +21.35 collected from centimeter to VHE during 2010 to investigate the properties of this source and discuss a possible emission model. The first hint of detection at VHE was observed by MAGIC on 2010 May 3, soon after a γ-ray flare detected by Fermi-LAT that peaked on April 29. The same emission mechanism may therefore be responsible for both the HE and VHE emission during the 2010 flaring episodes. Two optical peaks were detected on 2010 April 20 and June 30, close in time but not simultaneous with the two γ-ray peaks, while no clear connection was observed between the X-ray and γ-ray emission. An increasing flux density was observed in radio and mm bands from the beginning of 2009, in accordance with the increasing γ-ray activity observed by Fermi-LAT, and peaking on 2011 January 27 in the mm regime (230 GHz). We model the spectral energy distributions (SEDs) of 4C +21.35 for the two periods of the VHE detection and a quiescent state, using a one-zone model with the emission coming from a very compact region outside the broad line region. The three SEDs can be fit with a combination of synchrotron self-Compton and external Compton emission of seed photons from a dust torus, changing only the electron distribution parameters between the epochs. The fit of the optical/UV part of the spectrum for 2010 April 29 seems to favor an inner disk radius of

  2. On the Merging Cluster Abell 578 and Its Central Radio Galaxy 4C+67.13

    NASA Astrophysics Data System (ADS)

    Hagino, K.; Stawarz, Ł.; Siemiginowska, A.; Cheung, C. C.; Kozieł-Wierzbowska, D.; Szostek, A.; Madejski, G.; Harris, D. E.; Simionescu, A.; Takahashi, T.

    2015-06-01

    Here we analyze radio, optical, and X-ray data for the peculiar cluster Abell 578. This cluster is not fully relaxed and consists of two merging sub-systems. The brightest cluster galaxy (BCG), CGPG 0719.8+6704, is a pair of interacting ellipticals with projected separation ˜10 kpc, the brighter of which hosts the radio source 4C+67.13. The Fanaroff-Riley type-II radio morphology of 4C+67.13 is unusual for central radio galaxies in local Abell clusters. Our new optical spectroscopy revealed that both nuclei of the CGPG 0719.8+6704 pair are active, albeit at low accretion rates corresponding to the Eddington ratio ˜ {{10}-4} (for the estimated black hole masses of ˜ 3× {{10}8} {{M}⊙ } and ˜ {{10}9} {{M}⊙ }). The gathered X-ray (Chandra) data allowed us to confirm and to quantify robustly the previously noted elongation of the gaseous atmosphere in the dominant sub-cluster, as well as a large spatial offset (˜60 kpc projected) between the position of the BCG and the cluster center inferred from the modeling of the X-ray surface brightness distribution. Detailed analysis of the brightness profiles and temperature revealed also that the cluster gas in the vicinity of 4C+67.13 is compressed (by a factor of about ˜1.4) and heated (from ≃ 2.0 keV up to 2.7 keV), consistent with the presence of a weak shock (Mach number ˜1.3) driven by the expanding jet cocoon. This would then require the jet kinetic power of the order of ˜ {{10}45} erg s-1, implying either a very high efficiency of the jet production for the current accretion rate, or a highly modulated jet/accretion activity in the system. Based on service observations made with the WHT operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias.

  3. Role of p70S6K1-mediated phosphorylation of eIF4B and PDCD4 proteins in the regulation of protein synthesis.

    PubMed

    Dennis, Michael D; Jefferson, Leonard S; Kimball, Scot R

    2012-12-14

    Modulation of mRNA binding to the 40 S ribosomal subunit during translation initiation controls not only global rates of protein synthesis but also regulates the pattern of protein expression by allowing for selective inclusion, or exclusion, of mRNAs encoding particular proteins from polysomes. The mRNA binding step is modulated by signaling through a protein kinase known as the mechanistic target of rapamycin complex 1 (mTORC1). mTORC1 directly phosphorylates the translational repressors eIF4E binding proteins (4E-BP) 1 and 2, releasing them from the mRNA cap binding protein eIF4E, thereby promoting assembly of the eIF4E·eIF4G complex. mTORC1 also phosphorylates the 70-kDa ribosomal protein S6 kinase 1 (p70S6K1), which subsequently phosphorylates eIF4B, and programmed cell death 4 (PDCD4), which sequesters eIF4A from the eIF4E·eIF4G complex, resulting in repressed translation of mRNAs with highly structured 5'-untranslated regions. In the present study, we compared the role of the 4E-BPs in the regulation of global rates of protein synthesis to that of eIF4B and PDCD4. We found that maintenance of eIF4E interaction with eIF4G was not by itself sufficient to sustain global rates of protein synthesis in the absence of mTORC1 signaling to p70S6K1; phosphorylation of both eIF4B and PDCD4 was additionally required. We also found that the interaction of eIF4E with eIF4G was maintained in the liver of fasted rats as well as in serum-deprived mouse embryo fibroblasts lacking both 4E-BP1 and 4E-BP2, suggesting that the interaction of eIF4G with eIF4E is controlled primarily through the 4E-BPs.

  4. Characterization of LiFePO4/C Composite Thin Films Using Electrochemical Impedance Spectroscopy

    NASA Astrophysics Data System (ADS)

    Bajars, G.; Kucinskis, G.; Smits, J.; Kleperis, J.; Lusis, A.

    2012-08-01

    The composite LiFePO4/C thin films were prepared on steel substrate by radio frequency (RF) magnetron sputtering. Electrochemical properties of the obtained thin films were investigated by cyclic voltammetry charge-discharge measurements and electrochemical impedance spectroscopy (EIS). The films annealed at 550 °C exhibited a couple of redox peaks at 3.45 V vs. Li/Li+ characteristic for the electrochemical lithium insertion/extraction in LiFePO4. At low current rate such composite thin film showed a discharge capacity of over 110 mAh g-1. The dependence of charge transfer resistance, double layer capacitance and lithium diffusion coefficients on applied electrode potential were calculated from EIS data. Determined values of lithium diffusion coefficient were in the range from 8.3-10-13 cm2 s1 to 1.2-10-13 cm2 s-1 at 3.4 V and 3.7 V, respectively.

  5. BOREAS Level-4c AVHRR-LAC Ten-Day Composite Images: Surface Parameters

    NASA Technical Reports Server (NTRS)

    Cihlar, Josef; Chen, Jing; Huang, Fengting; Nickeson, Jaime; Newcomer, Jeffrey A.; Hall, Forrest G. (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study (BOREAS) Staff Science Satellite Data Acquisition Program focused on providing the research teams with the remotely sensed satellite data products they needed to compare and spatially extend point results. Manitoba Remote Sensing Center (MRSC) and BOREAS Information System (BORIS) personnel acquired, processed, and archived data from the Advanced Very High Resolution Radiometer (AVHRR) instruments on the NOAA-11 and -14 satellites. The AVHRR data were acquired by CCRS and were provided to BORIS for use by BOREAS researchers. These AVHRR level-4c data are gridded, 10-day composites of surface parameters produced from sets of single-day images. Temporally, the 10-day compositing periods begin 11-Apr-1994 and end 10-Sep-1994. Spatially, the data cover the entire BOREAS region. The data are stored in binary image format files. Note: Some of the data files on the BOREAS CD-ROMs have been compressed using the Gzip program.

  6. Boron analysis by electron microprobe using MoB4C layered synthetic crystals

    USGS Publications Warehouse

    McGee, J.J.; Slack, J.F.; Herrington, C.R.

    1991-01-01

    Preliminary electron microprobe studies of B distribution in minerals have been carried out using MoB4C-layered synthetic crystals to improve analytical sensitivity for B. Any microprobe measurements of the B contents of minerals using this crystal must include analyses for Cl to assess and correct for the interference of Cl X-rays on the BK?? peak. Microprobe analyses for B can be made routinely in tourmaline and other B-rich minerals, and minor B contents also can be determined in common rock-forming minerals. Incorporation of unusually high B contents in minerals other than borosilicates has been discovered in prograde and retrograde minerals in tourmalinites from the Broken Hill district, Australia, and may reflect high B activities produced during the metamorphism of tourmaline-rich rocks. -from Authors

  7. Interferometric Observations of 4C 21.53 and PSR 1937+214 at Decameter Wavelengths

    NASA Astrophysics Data System (ADS)

    Megn, A. V.; Braude, S. Ya.; Rashkovskii, S. L.; Sharykin, N. K.; Shepelev, V. A.; Inyutin, G. A.; Vashchishin, R. V.; Brazhenko, A. I.; Bulatsen, V. G.

    2002-02-01

    Preliminary resuts of interferometric observations of 4C 21.53 and PSR 1937+214 at 25 and 20 MHz are presented. The observations were obtained using the URAN-1 and URAN-2 interferometers, with baselines of 42.4 and 152.3 km. In addition to the pulsar radiation, which provides about 70% of the total flux of the object, radio emission from extended components with dimensions of several tens arcseconds has been detected for the first time. The angular size of the pulsar is 3″ at 25 MHz and 4″.8 at 20 MHz. The pulsar’s low-frequency spectrum deviates appreciably from the power law derived at higher frequencies.

  8. Dry Sliding Tribological Studies of AA6061-B4C-Gr Hybrid Composites

    NASA Astrophysics Data System (ADS)

    Monikandan, V. V.; Joseph, M. A.; Rajendrakumar, P. K.

    2016-10-01

    The dry sliding behavior of stir-cast AA6061-10 wt.% B4C composites containing 2.5, 5 and 7.5 wt.% graphite particles was studied as a function of applied load, sliding speed and sliding distance on a pin-on-disk tribotester. The wear rate and friction coefficient increased with increase in applied load and sliding distance. The increase in graphite addition reduced the increase in wear rate and friction coefficient in the sliding speed range 2-2.5 m/s. Scanning electron microscopy of the worn pin revealed a graphite tribolayer, and transmission electron microscopy revealed overlapping deformation bands under 30 N applied load. Upon increasing the applied load to 40 N, welded region with fine crystalline structure was formed due to dynamic recrystallization of AA6061 alloy matrix.

  9. CRL4B interacts with and coordinates the SIN3A-HDAC complex to repress CDKN1A and drive cell cycle progression.

    PubMed

    Ji, Qinghong; Hu, Huili; Yang, Fan; Yuan, Jupeng; Yang, Yang; Jiang, Liangqian; Qian, Yanyan; Jiang, Baichun; Zou, Yongxin; Wang, Yan; Shao, Changshun; Gong, Yaoqin

    2014-11-01

    CUL4B, a scaffold protein that assembles the CRL4B ubiquitin ligase complex, participates in the regulation of a broad spectrum of biological processes. Here, we demonstrate a crucial role of CUL4B in driving cell cycle progression. We show that loss of CUL4B results in a significant reduction in cell proliferation and causes G1 cell cycle arrest, accompanied by the upregulation of the cyclin-dependent kinase (CDK) inhibitors (CKIs) p21 and p57 (encoded by CDKN1A and CDKN1C, respectively). Strikingly, CUL4B was found to negatively regulate the function of p21 through transcriptional repression, but not through proteolysis. Furthermore, we demonstrate that CRL4B and SIN3A-HDAC complexes interact with each other and co-occupy the CDKN1A and CDKN1C promoters. Lack of CUL4B led to a decreased retention of SIN3A-HDAC components and increased levels of acetylated H3 and H4. Interestingly, the ubiquitylation function of CRL4B is not required for the stable retention of SIN3A-HDAC on the promoters of target genes. Thus, in addition to directly contributing to epigenetic silencing by catalyzing H2AK119 monoubiquitylation, CRL4B also facilitates the deacetylation function of SIN3A-HDAC. Our findings reveal a coordinated action between CRL4B and SIN3A-HDAC complexes in transcriptional repression.

  10. Solubility of alkali metal halides in the ionic liquid [C4C1im][OTf].

    PubMed

    Kuzmina, O; Bordes, E; Schmauck, J; Hunt, P A; Hallett, J P; Welton, T

    2016-06-28

    The solubilities of the metal halides LiF, LiCl, LiBr, LiI, NaF, NaCl, NaBr, NaI, KF, KCl, KBr, KI, RbCl, CsCl, CsI, were measured at temperatures ranging from 298.15 to 378.15 K in the ionic liquid 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([C4C1im][OTf]). Li(+), Na(+) and K(+) salts with anions matching the ionic liquid have also been investigated to determine how well these cations dissolve in [C4C1im][OTf]. This study compares the influence of metal cation and halide anion on the solubility of salts within this ionic liquid. The highest solubility found was for iodide salts, and the lowest solubility for the three fluoride salts. There is no outstanding difference in the solubility of salts with matching anions in comparison to halide salts. The experimental data were correlated employing several phase equilibria models, including ideal mixtures, van't Hoff, the λh (Buchowski) equation, the modified Apelblat equation, and the non-random two-liquid model (NRTL). It was found that the van't Hoff model gave the best correlation results. On the basis of the experimental data the thermodynamic dissolution parameters (ΔH, ΔS, and ΔG) were determined for the studied systems together with computed gas phase metathesis parameters. Dissolution depends on the energy difference between enthalpies of fusion and dissolution of the solute salt. This demonstrates that overcoming the lattice energy of the solid matrix is the key to the solubility of inorganic salts in ionic liquids.

  11. LiFePO4/C nanocomposites for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Eftekhari, Ali

    2017-03-01

    LiFePO4, as the most famous member of the family of olivine-type lithium transition metal phosphates, is one of the promising candidates for the cathodes of lithium-ion batteries. However, its battery performance is limited by its low electrical conductivity and slow Li solid-state diffusion. Various methods have been attempted to improve the battery performance of lithium iron phosphate. Among them, compositing the LiFePO4 with carbon nanomaterials seems to be the most promising, as it is facile and efficient. Carbon nanomaterials usually serve as a conductive agent to improve the electrical conductivity while increasing the material porosity in which the solid-state diffusion distances are significantly shortened. Owing to the popularity of various carbonaceous nanomaterials, there is no straightforward line of research for comparing the LiFePO4/C nanocomposites. This review aims to provide a general perspective based on the research achievements reported in the literature. While surveying the research findings reported in the literature, controversial issues are also discussed. The possible contribution of pseudocapacitance as a result of functionalized carbon or LiFePO4 lattice defects is described, since from a practical perspective, a LiFePO4/C electrode can be considered as a supercapacitor at high C rates (with a specific capacitance as large as 200 F g-1). The Li diffusion in LiFePO4 has not been well understood yet; while the Li diffusion within the LiFePO4 lattice seems to be quite fast, the peculiar interfacial electrochemistry of LiFePO4 slows down the diffusion within the entire electrode by a few orders of magnitude.

  12. 10B areal density: A novel approach for design and fabrication of B4C/6061Al neutron absorbing materials

    NASA Astrophysics Data System (ADS)

    Li, Yuli; Wang, Wenxian; Zhou, Jun; Chen, Hongsheng; Zhang, Peng

    2017-04-01

    In this paper, a novel approach to evaluate the neutron shielding performance of a boron-containing neutron absorbing material was proposed for the first time through the establishment of a direct relationship between 10B areal density (10BAD) of the material and its neutron absorption ratio. It is found when the 10BAD of a material is greater than 0.034 g/cm2, the material will achieve a good neutron shielding performance. Based on this proposed approach, B4C/6061Al composite plates with different B4C content (10 wt%, 20 wt%, 30 wt%) were successfully fabricated using vacuum hot pressing followed by hot-extrusion. The characteristics of the B4C/Al interface were studied in details using transmission electron microscopy (TEM), and the effects of B4C particle content on microstructure and mechanical properties of the Al matrix were investigated. Through current studies, B4C/6061Al composite plates possessing good neutron shielding performance and tensile strength are found to be able to be fabricated using either 20 wt% of B4C content with a plate thickness of 4.5 mm or 30 wt% B4C content with a plate thickness of 3 mm.

  13. Neutrons Flux Distributions of the Pu-Be Source and its Simulation by the MCNP-4B Code

    NASA Astrophysics Data System (ADS)

    Faghihi, F.; Mehdizadeh, S.; Hadad, K.

    Neutron Fluence rate of a low intense Pu-Be source is measured by Neutron Activation Analysis (NAA) of 197Au foils. Also, the neutron fluence rate distribution versus energy is calculated using the MCNP-4B code based on ENDF/B-V library. Theoretical simulation as well as our experimental performance are a new experience for Iranians to make reliability with the code for further researches. In our theoretical investigation, an isotropic Pu-Be source with cylindrical volume distribution is simulated and relative neutron fluence rate versus energy is calculated using MCNP-4B code. Variation of the fast and also thermal neutrons fluence rate, which are measured by NAA method and MCNP code, are compared.

  14. The calculated magnetic, electronic and thermodynamic properties of Ce3Co29Si4B10 compound

    NASA Astrophysics Data System (ADS)

    Huo, Jin-Rong; Wang, Xiao-Xu; Hu, Yao-Wen; Zhang, Guo-Hua; Cheng, Hai-Xia; Li, Lu; Qian, Ping

    2016-05-01

    The magnetic moment, lattice parameter and atom fraction coordinates for Ce3Co29Si4B10 are calculated by the first-principles GGA+U method, and the results indicate that the calculated and experimental values are basically accordant when U=2.6 eV. We study the interaction effect and orbital hybridization between Co and Ce atoms. The projected density of states at U=2.6 eV which provided by Co-2c, Ce-2b and Ce-4d sites are contrasted with else U values. Meanwhile the electron density of states for different sites and the distance between various atoms are exhibited. In addition, the thermodynamic properties of Ce3Co29Si4B10 are evaluated by using a series of interatomic pair potentials.

  15. Report on inspection of compliance with DOE Order 2030.4B at the Savannah River Site

    SciTech Connect

    1997-03-01

    The purpose of this inspection was to evaluate contractor compliance at the Savannah River Site (SRS) with Department of Energy (DOE) Order 2030.4B, {open_quotes}Reporting Fraud, Waste, And Abuse To The Office Of Inspector General.{close_quotes} The specific objective was to determine if the SRS management and operating (M&O) contractors were complying with the requirements in Paragraph 6.c. of DOE Order 2030.4B. These requirements are: (1) annual notification to employees of their duty to report allegations of fraud, waste, abuse, corruption, or mismanagement; (2) display and publish the DOE Office of Inspector General (OIG) Hotline telephone number in common areas of buildings; (3) display and publish the DOE OIG Hotline number in telephone books and newsletters; and (4) notify the OIG cases referred to other law enforcement entities.

  16. Application of trajectory optimization techniques to upper atmosphere sampling flights using the F4-C Phantom aircraft

    NASA Technical Reports Server (NTRS)

    Hague, D. S.; Merz, A. W.

    1975-01-01

    Altitude potential of an off-the-shelf F4-C aircraft is examined. It is shown that the standard F4-C has a maximum altitude capability in the region from 85000 to 95000 ft, depending on the minimum dynamic pressures deemed acceptable for adequate flight control. By using engine overspeed capability and by making use of prevailing winds in the stratosphere, it is suggested that the maximum altitude achievable by an F4-C should be in the vicinity of 95000 ft for routine flight operation. This altitude is well in excess of the minimum altitudes which must be achieved for monitoring the possible growth of suspected aerosol contaminants.

  17. FBXO44-Mediated Degradation of RGS2 Protein Uniquely Depends on a Cullin 4B/DDB1 Complex

    PubMed Central

    Sjögren, Benita; Swaney, Steven; Neubig, Richard R.

    2015-01-01

    The ubiquitin-proteasome system for protein degradation plays a major role in regulating cell function and many signaling proteins are tightly controlled by this mechanism. Among these, Regulator of G Protein Signaling 2 (RGS2) is a target for rapid proteasomal degradation, however, the specific enzymes involved are not known. Using a genomic siRNA screening approach, we identified a novel E3 ligase complex containing cullin 4B (CUL4B), DNA damage binding protein 1 (DDB1) and F-box protein 44 (FBXO44) that mediates RGS2 protein degradation. While the more typical F-box partners CUL1 and Skp1 can bind FBXO44, that E3 ligase complex does not bind RGS2 and is not involved in RGS2 degradation. These observations define an unexpected DDB1/CUL4B-containing FBXO44 E3 ligase complex. Pharmacological targeting of this mechanism provides a novel therapeutic approach to hypertension, anxiety, and other diseases associated with RGS2 dysregulation. PMID:25970626

  18. An improved method for expression and purification of functional human Ca(2+) transporter PMCA4b in Saccharomyces cerevisiae.

    PubMed

    Corbacho, Isaac; García-Prieto, Francisco F; Hinojosa, Ara E; Berrocal, María; Mata, Ana M

    2016-04-01

    Human plasma membrane calcium ATPases (PMCAs) are highly regulated transporters responsible for the extrusion of calcium out of the cell. Since calcium homeostasis is implicated in several diseases and neurodegenerative disorders, understanding PMCAs activity is crucial. One of the major hindrances is the availability of these proteins for functional and structural analysis. Here, using the yeast Saccharomyces cerevisiae system, we show a new and enhanced method for the expression of the full-length human PMCA isoform 4b (hPMCA4b) and a truncated form lacking its auto-inhibitory domain. We have also improved a method for the purification of the native isoform by calmodulin-agarose affinity chromatography, and developed a new method to purify the truncated isoform by glutathione-Sepharose affinity chromatography. One of the most relevant features of this work is that, when compared to PMCAs purification from pig brain, our method provides a pure single isoform instead of a mixture of isoforms, essential for fine-tuning the activity of PMCA4b. Another relevant feature is that the method described in this work has a superior yield of protein than previously established methods to purify PMCA proteins expressed in yeasts.

  19. SCN4B acts as a metastasis-suppressor gene preventing hyperactivation of cell migration in breast cancer

    PubMed Central

    Bon, Emeline; Driffort, Virginie; Gradek, Frédéric; Martinez-Caceres, Carlos; Anchelin, Monique; Pelegrin, Pablo; Cayuela, Maria-Luisa; Marionneau-Lambot, Séverine; Oullier, Thibauld; Guibon, Roseline; Fromont, Gaëlle; Gutierrez-Pajares, Jorge L.; Domingo, Isabelle; Piver, Eric; Moreau, Alain; Burlaud-Gaillard, Julien; Frank, Philippe G.; Chevalier, Stéphan; Besson, Pierre; Roger, Sébastien

    2016-01-01

    The development of metastases largely relies on the capacity of cancer cells to invade extracellular matrices (ECM) using two invasion modes termed ‘mesenchymal' and ‘amoeboid', with possible transitions between these modes. Here we show that the SCN4B gene, encoding for the β4 protein, initially characterized as an auxiliary subunit of voltage-gated sodium channels (NaV) in excitable tissues, is expressed in normal epithelial cells and that reduced β4 protein levels in breast cancer biopsies correlate with high-grade primary and metastatic tumours. In cancer cells, reducing β4 expression increases RhoA activity, potentiates cell migration and invasiveness, primary tumour growth and metastatic spreading, by promoting the acquisition of an amoeboid–mesenchymal hybrid phenotype. This hyperactivated migration is independent of NaV and is prevented by overexpression of the intracellular C-terminus of β4. Conversely, SCN4B overexpression reduces cancer cell invasiveness and tumour progression, indicating that SCN4B/β4 represents a metastasis-suppressor gene. PMID:27917859

  20. Magnetic phase transformations and superconductivity in Dy0.8Y0.2Rh4B4

    NASA Astrophysics Data System (ADS)

    Dmitriev, V. M.; Zaleskiĭ, A.; Khlybov, E. P.; Rybal'Chenko, L. F.; Khristenko, E. V.; Ishchenko, L. A.; Terekhov, A. V.; Kostyleva, I. E.; Lachenkov, S. A.

    2008-11-01

    The results of experimental studies of the magnetic and the superconducting properties of the compound Dy0.8Y0.2Rh4B4 with tetragonal body-centered crystal structure of the perovskite type (LuRu4B4) are presented. It is shown that the compound undergoes a paramagnet-ferrimagnet phase transition at the Curie temperature TC≈30.5K and its magnetic compensation temperature Tcomp≈17K. According to resistance measurements, the compound becomes a ferrimagnetic superconductor at Tconset≈5.9K which undergoes a ferrimagnet-antiferromagnet phase transition at TN≈2.7K while still remaining a superconductor. The specific heat exhibits a sharp maximum at this temperature. Point-contact Andreev reflection spectroscopy is used to measure the temperature and field dependences of the order parameter Δ(T ,H) and the temperature dependence of the upper critical field Hc2(T ). The dependences obtained differ radically from those generally accepted for conventional superconductors. The results obtained are discussed in connection with the possibility of triplet pairing in Dy0.8Y0.2Rh4B4.

  1. Dithiazolo[5,4-b:4',5'-d]phosphole: a highly luminescent electron-accepting building block.

    PubMed

    He, Xiaoming; Woo, Alva Y Y; Borau-Garcia, Javier; Baumgartner, Thomas

    2013-06-03

    A family of highly emissive dithiazolo[5,4-b:4',5'-d]phospholes has been designed and synthesized. The structures of two trivalent P species, as well as their corresponding P oxides, have been confirmed by X-ray crystallography. The parent dithiazolo[5,4-b:4',5'-d]phosphole oxide exhibits strong blue photoluminescence at λem = 442 nm, with an excellent quantum yield efficiency of ϕPL = 0.81. The photophysical properties of these compounds can be easily tuned by extension of the conjugation and modification of the phosphorus center. Compared with the established dithieno[3,2-b:2',3'-d]phosphole system, the incorporation of electronegative nitrogen atoms leads to significantly lowered frontier orbital energy levels, as validated by both electrochemistry and theoretical calculations, thus suggesting that the dithiazolo[5,4-b:4',5'-d]phospholes are valuable, air-stable, n-type conjugated materials. These new building blocks have been further applied to the construction of an extended oligomer with fluorene. Extension of the dithiazolophosphole core with triazole units through click reactions also provides a suitable N,N-chelating moiety for metal binding and a representative molecular species was successfully used as a selective colorimetric and fluorescent sensor for Cu(II) ions.

  2. Association of PDE4B Polymorphisms with Susceptibility to Schizophrenia: A Meta-Analysis of Case-Control Studies

    PubMed Central

    Feng, Yanguo; Cheng, Dejun; Zhang, Chaofeng; Li, Yuchun; Zhang, Zhiying; Wang, Juan; Shi, Yuzhong

    2016-01-01

    Background The PDE4B single nucleotide polymorphisms (SNPs) have been reported to be associated with schizophrenia risk. However, current findings are ambiguous or even conflicting. To better facilitate the understanding the genetic role played by PDE4B in susceptibility to schizophrenia, we collected currently available data and conducted this meta-analysis. Methods A comprehensive electronic literature searching of PubMed, Embase, Web of Science and Cochrane Library was performed. The association between PDE4B SNPs and schizophrenia was evaluated by odds ratios (ORs) and 95% confidence intervals (CIs) under allelic, dominant and recessive genetic models. The random effects model was utilized when high between-study heterogeneity (I2 > 50%) existed, otherwise the fixed effects model was used. Results Five studies comprising 2376 schizophrenia patients and 3093 controls were finally included for meta-analysis. The rs1040716 was statistically significantly associated with schizophrenia risk in Asian and Caucasian populations under dominant model (OR = 0.87, 95% CI: 0.76–0.99, P = 0.04). The rs2180335 was significantly related with schizophrenia risk in Asian populations under allelic (OR = 0.82, 95% CI: 0.72–0.93, P = 0.003) and dominant (OR = 0.75, 95% CI: 0.64–0.88, P < 0.001) models. A significant association was also observed between rs4320761 and schizophrenia in Asian populations under allelic model (OR = 0.87, 95% CI: 0.75–1.00, P = 0.048). In addition, a strong association tendency was found between rs6588190 and schizophrenia in Asian populations under allelic model (OR = 0.87, 95% CI: 0.76–1.00, P = 0.055). Conclusion This meta-analysis suggests that PDE4B SNPs are genetically associated with susceptibility to schizophrenia. However, due to limited sample size, more large-scale, multi-racial association studies are needed to further clarify the genetic association between various PDE4B variants and schizophrenia. PMID:26756575

  3. Two C-terminal variants of NBC4, a new member of the sodium bicarbonate cotransporter family: cloning, characterization, and localization.

    PubMed

    Pushkin, A; Abuladze, N; Newman, D; Lee, I; Xu, G; Kurtz, I

    2000-07-01

    We report the cloning, characterization, and chromosomal assignment of a new member of the sodium bicarbonate cotransporter (NBC) family, NBC4. The NBC4 gene was mapped to chromosome 2p13 and is a new candidate gene for Alstrom syndrome. Two variants of the transporter have been isolated from human testis and heart, which differ in their C termini. NBC4a encodes a 1137-residue polypeptide and is widely expressed in various tissues, including liver, testis, and spleen. NBC4b is identical to NBC4a except that it has a 16-nucleotide insert, creating a C-terminal frame shift. NBC4b encodes a 1074-residue polypeptide and is highly expressed in heart. Amino acids 1-1046 are common to both NBC4 variants. NBC4a has two protein-interacting domains that are lacking in NBC4b: a proline-rich sequence, PPPSVIKIP (amino acids 1102-1110), and a consensus PDZ-interacting domain, SYSL (1134-1137). NBC4b lacks the stretch of charged residues present in the C terminus of NBC4a and other members of the NBC family. Unlike other members of the NBC family, both NBC4a and NBC4b have a unique glycine-rich region (amino acids 440-469). In comparison with other members of the bicarbonate transport superfamily, NBC4a and NBC4b are most similar structurally to the electrogenic sodium bicarbonate cotransporters (NBC1).

  4. Molecular Mechanisms of Viral and Host Cell Substrate Recognition by Hepatitis C Virus NS3/4A Protease

    SciTech Connect

    Romano, Keith P.; Laine, Jennifer M.; Deveau, Laura M.; Cao, Hong; Massi, Francesca; Schiffer, Celia A.

    2011-08-16

    Hepatitis C NS3/4A protease is a prime therapeutic target that is responsible for cleaving the viral polyprotein at junctions 3-4A, 4A4B, 4B5A, and 5A5B and two host cell adaptor proteins of the innate immune response, TRIF and MAVS. In this study, NS3/4A crystal structures of both host cell cleavage sites were determined and compared to the crystal structures of viral substrates. Two distinct protease conformations were observed and correlated with substrate specificity: (i) 3-4A, 4A4B, 5A5B, and MAVS, which are processed more efficiently by the protease, form extensive electrostatic networks when in complex with the protease, and (ii) TRIF and 4B5A, which contain polyproline motifs in their full-length sequences, do not form electrostatic networks in their crystal complexes. These findings provide mechanistic insights into NS3/4A substrate recognition, which may assist in a more rational approach to inhibitor design in the face of the rapid acquisition of resistance.

  5. Molecular Mechanisms of Viral and Host Cell Substrate Recognition by Hepatitis C Virus NS3/4A Protease▿

    PubMed Central

    Romano, Keith P.; Laine, Jennifer M.; Deveau, Laura M.; Cao, Hong; Massi, Francesca; Schiffer, Celia A.

    2011-01-01

    Hepatitis C NS3/4A protease is a prime therapeutic target that is responsible for cleaving the viral polyprotein at junctions 3-4A, 4A4B, 4B5A, and 5A5B and two host cell adaptor proteins of the innate immune response, TRIF and MAVS. In this study, NS3/4A crystal structures of both host cell cleavage sites were determined and compared to the crystal structures of viral substrates. Two distinct protease conformations were observed and correlated with substrate specificity: (i) 3-4A, 4A4B, 5A5B, and MAVS, which are processed more efficiently by the protease, form extensive electrostatic networks when in complex with the protease, and (ii) TRIF and 4B5A, which contain polyproline motifs in their full-length sequences, do not form electrostatic networks in their crystal complexes. These findings provide mechanistic insights into NS3/4A substrate recognition, which may assist in a more rational approach to inhibitor design in the face of the rapid acquisition of resistance. PMID:21507982

  6. REVERSIBLE HYDROGEN STORAGE IN A LiBH{sub 4}-C{sub 60} NANOCOMPOSITE

    SciTech Connect

    Teprovich, J.; Zidan, R.; Peters, B.; Wheeler, J.

    2013-08-06

    Reversible hydrogen storage in a LiBH{sub 4}:C{sub 60} nanocomposite (70:30 wt. %) synthesized by solvent-assisted mixing has been demonstrated. During the solvent-assisted mixing and nanocomposite formation, a chemical reaction occurs in which the C{sub 60} cages are significantly modified by polymerization as well as by hydrogenation (fullerane formation) in the presence of LiBH{sub 4}. We have determined that two distinct hydrogen desorption events are observed upon rehydrogenation of the material, which are attributed to the reversible formation of a fullerane (C{sub 60}H{sub x}) as well as a LiBH4 species. This system is unique in that the carbon species (C{sub 60}) actively participates in the hydrogen storage process which differs from the common practice of melt infiltration of high surface area carbon materials with LiBH{sub 4} (nanoconfinment effect). This nanocomposite demonstrated good reversible hydrogen storage properties as well as the ability to absorb hydrogen under mild conditions (pressures as low as 10 bar H{sub 2} or temperatures as low as 150°C). The nanocomposite was characterized by TGA-RGA, DSC, XRD, LDI-TOF-MS, FTIR, 1H NMR, and APPI MS.

  7. Performance of the MTR core with MOX fuel using the MCNP4C2 code.

    PubMed

    Shaaban, Ismail; Albarhoum, Mohamad

    2016-08-01

    The MCNP4C2 code was used to simulate the MTR-22 MW research reactor and perform the neutronic analysis for a new fuel namely: a MOX (U3O8&PuO2) fuel dispersed in an Al matrix for One Neutronic Trap (ONT) and Three Neutronic Traps (TNTs) in its core. Its new characteristics were compared to its original characteristics based on the U3O8-Al fuel. Experimental data for the neutronic parameters including criticality relative to the MTR-22 MW reactor for the original U3O8-Al fuel at nominal power were used to validate the calculated values and were found acceptable. The achieved results seem to confirm that the use of MOX fuel in the MTR-22 MW will not degrade the safe operational conditions of the reactor. In addition, the use of MOX fuel in the MTR-22 MW core leads to reduce the uranium fuel enrichment with (235)U and the amount of loaded (235)U in the core by about 34.84% and 15.21% for the ONT and TNTs cases, respectively.

  8. Intermittent Jet Activity in the Radio Galaxy 4C29.30?

    SciTech Connect

    Jamrozy, M.; Konar, C.; Saikia, D.J.; Stawarz, L.; Mack, K.-H.; Siemiginowska, A.; /Harvard-Smithsonian Ctr. Astrophys.

    2007-04-02

    We present radio observations at frequencies ranging from 240 to 8460 MHz of the radio galaxy 4C29.30 (J0840+2949) using the Giant Metrewave Radio Telescope (GMRT), the Very Large Array (VLA) and the Effelsberg telescope. We report the existence of weak extended emission with an angular size of {approx} 520 arcsec (639 kpc) within which a compact edge-brightened double-lobed source with a size of 29 arcsec (36 kpc) is embedded. We determine the spectrum of the inner double from 240 to 8460 MHz and show that it has a single power-law spectrum with a spectral index is {approx} 0.8. Its spectral age is estimated to be 33 Myr. The extended diffuse emission has a steep spectrum with a spectral index of {approx} 1.3 and a break frequency 240 MHz. The spectral age is {approx}>200 Myr, suggesting that the extended diffuse emission is due to an earlier cycle of activity. We reanalyze archival x-ray data from Chandra and suggest that the x-ray emission from the hotspots consists of a mixture of nonthermal and thermal components, the latter being possibly due to gas which is shock heated by the jets from the host galaxy.

  9. Electrochemical properties of Li2 FeSiO4 /C nanocomposites prepared by sol-gel and hydrothermal methods

    NASA Astrophysics Data System (ADS)

    Kumar, Ajay; Jayakumar, O. D.; Naik, Vaman M.; Nazri, Gholam A.; Naik, Ratna

    Li2FeSiO4 is considered as potential cathode material for next generation lithium ion batteries because of its high specific theoretical capacity, low cost, and safety. However, it suffers from poor electronic conductivity and slow lithium ion diffusion in the solid phase. To address these issues, we have studied mesoporous Li2FeSiO4/C composites synthesized by sol-gel (SG) and hydrothermal (HT) methods using tri-block copolymer (P123) as carbon source and structure directing agent. The structure and morphology of the composites were characterized by XRD, SEM and TEM and the surface area and pore size distribution were measured by using N2 adsorption/desorption. Galvanostatic cycling, electrochemical impedance spectroscopy, and cyclic voltammetry were used to evaluate the electrochemical performance of the Li2FeSiO4/C composites. The Li2FeSiO4/C (HT) composites show a superior electrochemical performance compared to Li2FeSiO4/C (SG). At C/30 rate, the discharge capacity of Li2FeSiO4/C (HT) reached ~276 mAh/g in the 1.5-4.6 V window and shows better rate capability and stability at high rates. We attribute the improved electrochemical performance of Li2FeSiO4/C (HT) to its large surface area and reduced particle size. The details of the study will be presented.

  10. Isolation and structure of ciguatoxin-4A, a new ciguatoxin precursor, from cultures of dinoflagellate Gambierdiscus toxicus and parrotfish Scarus gibbus.

    PubMed

    Satake, M; Ishibashi, Y; Legrand, A M; Yasumoto, T

    1996-12-01

    A new ciguatoxin congener, ciguatoxin-4A (CTX4A), was isolated from cultures of marine dinoflagellate Gambierdiscus toxicus, and its structure was elucidated to be 52-epiciguatoxin-4B on the basis of spectroscopic data. Chromatographic and spectral comparisons indicated that CTX4A was identical with a structurally unelucidated congener known as scaritoxin or SG1.

  11. Douglas OA-4A Dolphin

    NASA Technical Reports Server (NTRS)

    1938-01-01

    Douglas OA-4A Dolphin: This twin-engine Douglas OA-4A Dolphin was unusual in comparison with other OA-4s in that it employed a nose wheel instead of a tail wheel during its NACA testing at Langley. Here is is seen in the NACA hangar in September 1938.

  12. Giant magnetic coercivity in YNi4B-type SmNi3TB (T=Mn-Cu) solid solutions

    NASA Astrophysics Data System (ADS)

    Yao, Jinlei; Yan, Chang; Yapaskurt, V. O.; Morozkin, A. V.

    2016-12-01

    The effects of transition metal substitution for Ni on the magnetic properties of the YNi4B-type SmNi4B via SmNi3TB (T=Mn, Fe, Co, Cu) solid solutions have been investigated. SmNi4B, SmNi3MnB, SmNi3FeB, SmNi3CoB and SmNi3CuB show ferromagnetic ordering at 40 K, 210 K, 322 K, 90 K and 57 K and field sensitive metamagnetic-like transitions at 15 K, 100 K, 185 K, 55 K and 15 K in a magnetic field of 10 kOe, respectively. The magnetocaloric effects of SmNi3TB (T=Mn-Cu) were calculated in terms of isothermal magnetic entropy change (ΔSm). The magnetic entropy ΔSm reaches value of -0.94 J/kg K at 40 K for SmNi4B, -1.5 J/kg K at 205 K for SmNi3MnB, -0.54 J/kg K at 320 K for SmNi3FeB, -0.49 J/kg K at 90 K for SmNi3CoB and -0.54 J/kg K at 60 K for SmNi3CuB in field change of 0-50 kOe around the Curie temperature. They show positive ΔSm of +0.71 J/kg K at ~10 K for SmNi4B, +1.69 J/kg K at 30 K for SmNi3MnB, +0.89 J/kg K at 110 K for SmNi3FeB, +1.08 J/kg K at 25 K for SmNi3CoB and +1.12 J/kg K at 10 K for SmNi3CuB in field change of 0-50 kOe around the low temperature metamagnetic-like transition. Below the field induced transition temperature (change of magnetic structure), SmNi3TB (T=Mn-Cu) exhibits giant magnetic coercivity of 74 kOe at 5 K for SmNi4B, 69 kOe at 20 K (90 kOe at 10 K) for SmNi3MnB, 77 kOe at 60 K for SmNi3FeB, 88 kOe at 20 K for SmNi3CoB and 52 kOe at 5 K for SmNi3CuB.

  13. Estrogen receptor alpha prevents bladder cancer via INPP4B inhibited akt pathway in vitro and in vivo.

    PubMed

    Hsu, Iawen; Yeh, Chiuan-Ren; Slavin, Spencer; Miyamoto, Hiroshi; Netto, George J; Tsai, Yu-Chieh; Muyan, Mesut; Wu, Xue-Ru; Messing, Edward M; Guancial, Elizabeth A; Yeh, Shuyuan

    2014-09-15

    Clinical reports show males have a higher bladder cancer (BCa) incidence than females. The sexual difference of BCa occurrence suggests that estrogen and its receptors may affect BCa development. Estrogen receptor alpha (ERα) is the classic receptor to convey estrogen signaling, however, the function of ERα in BCa development remains largely unknown. To understand the in vivo role of ERα in BCa development, we generated total and urothelial specific ERα knockout mice (ERαKO) and used the pre- carcinogen BBN to induce BCa. Earlier reports showed that ERα promotes breast and ovarian cancers in females. Surprisingly and of clinical importance, our results showed that ERα inhibits BCa development and loss of the ERα gene results in an earlier onset and higher incidence of BBN-induced in vivo mouse BCa. Supportively, carcinogen induced malignant transformation ability was reduced in ERα expressing urothelial cells as compared to ERα negative cells. Mechanism studies suggest that ERα could control the expression of INPP4B to reduce AKT activity and consequently reduce BCa cell growth. In addition, IHC staining of clinical sample analyses show that INPP4B expression, in correlation with reduced ERα, is significantly reduced in human BCa specimens. Together, this is the first report using the in vivo cre-loxP gene knockout mouse model to characterize ERα roles in BCa development. Our studies provide multiple in vitro cell studies and in vivo animal model data as well as human BCa tissue analyses to prove ERα plays a protective role in BCa initiation and growth at least partly via modulating the INPP4B/Akt pathway.

  14. The warm absorber in the radio-loud quasar 4C +74.26

    NASA Astrophysics Data System (ADS)

    Di Gesu, L.; Costantini, E.

    2016-10-01

    Outflows of photoionized gas are commonly detected in the X-ray spectra of Seyfert 1 galaxies. However, the evidence for this phenomenon in broad line radio galaxies, which are analogous to Seyfert 1 galaxies in the radio-loud regime, has so far been scarce. Here, we present the analysis of the X-ray absorption in the radio-loud quasar 4C +74.26. With the aim of characterizing the kinetic and the ionization conditions of the absorbing material, we fitted jointly the XMM-Newton Reflection Grating Spectrometer (RGS) and the Chandra High Energy Transmission Grating Spectrometer (HETGS) spectra, which were taken 4 months apart. The intrinsic continuum flux did not vary significantly during this time lapse. The spectrum shows the absorption signatures (e.g., Fe-UTA, O vii, and Ne vii-Ne x) of a photoionized gas outflow (NH ~ 3.5 × 1021 cm-2, log ξ ~ 2.6, vout ~ 3600 km s-1) located at the redshift of source. We estimate that the gas is located outside the broad line region but within the boundaries of the putative torus. This ionized absorber is consistent with the X-ray counterpart of a polar scattering outflow reported in the optical band for this source. The kinetic luminosity carried by the outflow is insufficient to produce a significant feedback is this quasar. Finally, we show that the heavy soft X-ray absorption that was noticed in the past for this source arises mostly in the Galactic interstellar medium.

  15. Surface Structure Spread Single Crystals (S4C): Preparation and characterization

    SciTech Connect

    de Alwis, A.; Holsclaw, B.; Pushkarev, V. V.; Reinicker, A.; Lawton, T. J.; Blecher, M. E.; Sykes, E. C. H.; Gellman, A. J.

    2013-02-01

    A set of six spherically curved Cu single crystals referred to as Surface Structure Spread Single Crystals (S{sup 4}Cs) has been prepared in such a way that their exposed surfaces collectively span all possible crystallographic surface orientations that can be cleaved from the face centered cubic Cu lattice. The method for preparing these S{sup 4}Cs and for finding the high symmetry pole point are described. Optical profilometry has been used to determine the true shapes of the S{sup 4}Cs and show that over the majority of the surface, the shape is extremely close to that of a perfect sphere. The local orientations of the surfaces lie within ±1{degree} of the orientation expected on the basis of the spherical shape; their orientation is as good as that of many commercially prepared single crystals. STM imaging has been used to characterize the atomic level structure of the Cu(111)±11{degree}-S{sup 4}C. This has shown that the average step densities and the average step orientations match those expected based on the spherical shape. In other words, although there is some distribution of step-step spacing and step orientations, there is no evidence of large scale reconstruction or faceting. The Cu S{sup 4}Cs have local structures based on the ideal termination of the face centered cubic Cu lattice in the direction of termination. The set of Cu S{sup 4}Cs will serve as the basis for high throughput investigations of structure sensitive surface chemistry on Cu.

  16. First report of severe parainfluenza virus 4B and rhinovirus C coinfection in a liver transplant recipient treated with immunoglobulin.

    PubMed

    Sridhar, Siddharth; Luk, Hayes K H; Lau, Susanna K P; Woo, Patrick C Y

    2014-12-01

    We describe the first reported case of severe pneumonia due to coinfection by parainfluenza virus type 4B and rhinovirus C in a liver transplant recipient. The patient responded promptly to intravenous immunoglobulin and timely infection control measures prevented spreading of the infections. This report highlights respiratory viral coinfections as a possible cause of severe morbidity in transplant recipients and the importance of efficient molecular diagnostic technologies with major impact on clinical practice in a transplant center. It also describes a potential therapeutic strategy for such patients.

  17. Developing VUV spectroscopy for protein folding and material luminescence on beamline 4B8 at the Beijing Synchrotron Radiation Facility.

    PubMed

    Tao, Ye; Huang, Yan; Gao, Zhenghua; Zhuang, Hao; Zhou, Aiyu; Tan, Yinglei; Li, Daowu; Sun, Shuaishuai

    2009-11-01

    The new 4B8 beamline provides UV-VUV light in the wavelength range from 360 to 120 nm. It uniquely enables two kinds of spectroscopy measurements: synchrotron radiation circular dichroism spectroscopy and VUV excited fluorescence spectroscopy. The former is mainly used in protein secondary structure studies, and the latter in VUV excited luminescent materials research. Remote access to fluorescence measurement has been realised and users can collect data online. Besides steady-state measurements, fluorescence lifetime measurements have been established using the time domain method, while a laser-induced temperature jump is under development for protein folding dynamics using circular dichroism as a probe.

  18. ATG4B contains a C-terminal LIR motif important for binding and efficient cleavage of mammalian orthologs of yeast Atg8.

    PubMed

    Skytte Rasmussen, Mads; Mouilleron, Stéphane; Kumar Shrestha, Birendra; Wirth, Martina; Lee, Rebecca; Bowitz Larsen, Kenneth; Abudu Princely, Yakubu; O'Reilly, Nicola; Sjøttem, Eva; Tooze, Sharon A; Lamark, Trond; Johansen, Terje

    2017-02-15

    The cysteine protease ATG4B cleaves off one or more C-terminal residues of the inactive proform of proteins of the ortholog and paralog LC3 and GABARAP subfamilies of yeast Atg8 to expose a C-terminal glycine that is conjugated to phosphatidylethanolamine during autophagosome formation. We show that ATG4B contains a C-terminal LC3-interacting region (LIR) motif important for efficient binding to and cleavage of LC3 and GABARAP proteins. We solved the crystal structures of the GABARAPL1-ATG4B C-terminal LIR complex. Analyses of the structures and in vitro binding assays, using specific point mutants, clearly showed that the ATG4B LIR binds via electrostatic-, aromatic HP1 and hydrophobic HP2 pocket interactions. Both these interactions and the catalytic site-substrate interaction contribute to binding between LC3s or GABARAPs and ATG4B. We also reveal an unexpected role for ATG4B in stabilizing the unlipidated forms of GABARAP and GABARAPL1. In mouse embryonic fibroblast (MEF) atg4b knockout cells, GABARAP and GABARAPL1 were unstable and degraded by the proteasome. Strikingly, the LIR motif of ATG4B was required for stabilization of the unlipidated forms of GABARAP and GABARAPL1 in cells.

  19. Human X-linked Intellectual Disability Factor CUL4B Is Required for Post-meiotic Sperm Development and Male Fertility

    PubMed Central

    Lin, Chien-Yu; Chen, Chun-Yu; Yu, Chih-Hsiang; Yu, I-Shing; Lin, Shu-Rung; Wu, June-Tai; Lin, Ying-Hung; Kuo, Pao-Lin; Wu, Jui-Ching; Lin, Shu-Wha

    2016-01-01

    In this study, we demonstrate that an E3-ubiquitin ligase associated with human X-linked intellectual disability, CUL4B, plays a crucial role in post-meiotic sperm development. Initially, Cul4bΔ/Y male mice were found to be sterile and exhibited a progressive loss in germ cells, thereby leading to oligoasthenospermia. Adult Cul4b mutant epididymides also contained very low numbers of mature spermatozoa, and these spermatazoa exhibited pronounced morphological abnormalities. In post-meiotic spermatids, CUL4B was dynamically expressed and mitosis of spermatogonia and meiosis of spermatocytes both appeared unaffected. However, the spermatids exhibited significantly higher levels of apoptosis during spermiogenesis, particularly during the acrosome phase through the cap phase. Comparative proteomic analyses identified a large-scale shift between wild-type and Cul4b mutant testes during early post-meiotic sperm development. Ultrastructural pathology studies further detected aberrant acrosomes in spermatids and nuclear morphology. The protein levels of both canonical and non-canonical histones were also affected in an early spermatid stage in the absence of Cul4b. Thus, X-linked CUL4B appears to play a critical role in acrosomal formation, nuclear condensation, and in regulating histone dynamics during haploid male germ cell differentiation in relation to male fertility in mice. Thus, it is possible that CUL4B-selective substrates are required for post-meiotic sperm morphogenesis. PMID:26832838

  20. 15 CFR 744.9 - Restrictions on certain exports and reexports of cameras controlled by ECCN 6A003.b.4.b.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... reexports of cameras controlled by ECCN 6A003.b.4.b. 744.9 Section 744.9 Commerce and Foreign Trade... on certain exports and reexports of cameras controlled by ECCN 6A003.b.4.b. (a) General prohibitions... license is required to export or reexport to any destination other than Canada cameras described in...

  1. Human X-linked Intellectual Disability Factor CUL4B Is Required for Post-meiotic Sperm Development and Male Fertility.

    PubMed

    Lin, Chien-Yu; Chen, Chun-Yu; Yu, Chih-Hsiang; Yu, I-Shing; Lin, Shu-Rung; Wu, June-Tai; Lin, Ying-Hung; Kuo, Pao-Lin; Wu, Jui-Ching; Lin, Shu-Wha

    2016-02-02

    In this study, we demonstrate that an E3-ubiquitin ligase associated with human X-linked intellectual disability, CUL4B, plays a crucial role in post-meiotic sperm development. Initially, Cul4b(Δ)/Y male mice were found to be sterile and exhibited a progressive loss in germ cells, thereby leading to oligoasthenospermia. Adult Cul4b mutant epididymides also contained very low numbers of mature spermatozoa, and these spermatazoa exhibited pronounced morphological abnormalities. In post-meiotic spermatids, CUL4B was dynamically expressed and mitosis of spermatogonia and meiosis of spermatocytes both appeared unaffected. However, the spermatids exhibited significantly higher levels of apoptosis during spermiogenesis, particularly during the acrosome phase through the cap phase. Comparative proteomic analyses identified a large-scale shift between wild-type and Cul4b mutant testes during early post-meiotic sperm development. Ultrastructural pathology studies further detected aberrant acrosomes in spermatids and nuclear morphology. The protein levels of both canonical and non-canonical histones were also affected in an early spermatid stage in the absence of Cul4b. Thus, X-linked CUL4B appears to play a critical role in acrosomal formation, nuclear condensation, and in regulating histone dynamics during haploid male germ cell differentiation in relation to male fertility in mice. Thus, it is possible that CUL4B-selective substrates are required for post-meiotic sperm morphogenesis.

  2. 15 CFR 744.9 - Restrictions on certain exports and reexports of cameras controlled by ECCN 6A003.b.4.b.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... reexports of cameras controlled by ECCN 6A003.b.4.b. 744.9 Section 744.9 Commerce and Foreign Trade... on certain exports and reexports of cameras controlled by ECCN 6A003.b.4.b. (a) General prohibitions... license is required to export or reexport to any destination other than Canada cameras described in...

  3. 15 CFR 744.9 - Restrictions on certain exports and reexports of cameras controlled by ECCN 6A003.b.4.b.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... reexports of cameras controlled by ECCN 6A003.b.4.b. 744.9 Section 744.9 Commerce and Foreign Trade... on certain exports and reexports of cameras controlled by ECCN 6A003.b.4.b. (a) General prohibitions... license is required to export or reexport to any destination other than Canada cameras described in...

  4. eNOS gene Glu298Asp and 4b/a polymorphisms are associated with renal function parameters in Mexican patients with Fabry disease.

    PubMed

    Marin-Medina, A; Brambila-Tapia, A J L; Picos-Cárdenas, V J; Gallegos-Arreola, M P; Figuera, L E

    2016-10-24

    Fabry disease (FD) is an inherited X-linked lysosomal disease that causes renal failure in a high percentage of affected individuals. The eNOS gene encodes for endothelial nitric oxide synthase, which plays an important role in glomerular hemodynamics. This gene has two main polymorphisms (Glu298Asp and 4b/a) that have been studied in the context of many different diseases, including those involving cardiovascular and renal alterations. Considering the lack of information regarding eNOS variants and FD, we investigated whether there were associations between eNOS genetic variants and renal function parameters in Mexican patients with FD and renal impairment. In total, 15 FD patients with renal alterations were included in the present study, and associations between eNOS polymorphisms and renal function parameters (urea, creatinine, and GFR) were evaluated. The Asp298 and 4a alleles of the eNOS gene were found to be significantly associated with increased levels of urea and creatinine, and a decreased glomerular filtration rate in FD patients, and this association behaved in a co-dominant fashion. Our results coincide with previous reports showing an association between these polymorphisms and kidney disease, and along with other studies regarding their role in the nitric oxide pathway, suggest that these variants affect the severity of nephropathy in patients with FD.

  5. Intracellular membrane association of the N-terminal domain of classical swine fever virus NS4B determines viral genome replication and virulence.

    PubMed

    Tamura, Tomokazu; Ruggli, Nicolas; Nagashima, Naofumi; Okamatsu, Masatoshi; Igarashi, Manabu; Mine, Junki; Hofmann, Martin A; Liniger, Matthias; Summerfield, Artur; Kida, Hiroshi; Sakoda, Yoshihiro

    2015-09-01

    Classical swine fever virus (CSFV) causes a highly contagious disease in pigs that can range from a severe haemorrhagic fever to a nearly unapparent disease, depending on the virulence of the virus strain. Little is known about the viral molecular determinants of CSFV virulence. The nonstructural protein NS4B is essential for viral replication. However, the roles of CSFV NS4B in viral genome replication and pathogenesis have not yet been elucidated. NS4B of the GPE-  vaccine strain and of the highly virulent Eystrup strain differ by a total of seven amino acid residues, two of which are located in the predicted trans-membrane domains of NS4B and were described previously to relate to virulence, and five residues clustering in the N-terminal part. In the present study, we examined the potential role of these five amino acids in modulating genome replication and determining pathogenicity in pigs. A chimeric low virulent GPE- -derived virus carrying the complete Eystrup NS4B showed enhanced pathogenicity in pigs. The in vitro replication efficiency of the NS4B chimeric GPE-  replicon was significantly higher than that of the replicon carrying only the two Eystrup-specific amino acids in NS4B. In silico and in vitro data suggest that the N-terminal part of NS4B forms an amphipathic α-helix structure. The N-terminal NS4B with these five amino acid residues is associated with the intracellular membranes. Taken together, this is the first gain-of-function study showing that the N-terminal domain of NS4B can determine CSFV genome replication in cell culture and viral pathogenicity in pigs.

  6. High-performance, nanostructure LiMnPO4/C composites synthesized via one-step solid state reaction

    NASA Astrophysics Data System (ADS)

    Zheng, Jugong; Ni, Liang; Lu, Yanwen; Qin, Cancan; Liu, Panxing; Wu, Tongfu; Tang, Yuefeng; Chen, Yanfeng

    2015-05-01

    LiMnPO4 is proposed as more promising cathode material as LiFePO4, while poor electronic conductivity and Jahn-Teller effects during charge/discharge processes hinder the electrochemical performance. To overcome these problems, one-step solid state reaction method is developed to synthesize LiMnPO4/C composites, which is with nanostructure, high crystallinity and good carbon coating. Manganese oxide sources and calcination temperature are investigated as factors for preparing high-performance LiMnPO4/C for Li-ion batteries. The results show that the LiMnPO4/C composites prepared with mixed manganese oxide deliver a superior initial capacity of 153 mAh g-1 at 0.05 C and high rate performance with discharge capacities of 123 mAh g-1 at 1 C and 103 mAh g-1 at 2 C. And the LiMnPO4/C composites synthesized at 600 °C can retain 94% of the initial capacity after 200 cycles at 1 C, revealing a stable cycling stability. Therefore, one-step solid state reaction brings to light the synthesis of high performance LiMnPO4/C cathode materials and is suitable for large scale production.

  7. Facile synthesis of Fe3O4@C hollow nanospheres and their application in polluted water treatment

    NASA Astrophysics Data System (ADS)

    Zhang, Yuanguang; Xu, Shihao; Xia, Hongyu; Zheng, Fangcai

    2016-11-01

    Nanostructured carbon-based materials, such as carbon nanotube arrays have shown respectable removal ability for heavy metal ions and organic dyes in aqueous solution. Although the carbon-based materials exhibited excellent removal ability, the separation of them from the aqueous solution is difficult and time-consuming. Here we demonstrated a novel and facile route for the large-scale fabrication of Fe3O4@C hollow nanospheres, with using ferrocene as a single reagent and SiO2 as a template. The as-prepared Fe3O4@C hollow nanospheres exhibited adsorption ability for heavy metal ions and organic dyes from aqueous solution, and can be easily separated by an external magnet. When the as-prepared Fe3O4@C hollow nanospheres were mixed with the aqueous solution of Hg2+ within 15 min, the removal efficiency was 90.3%. The as-prepared Fe3O4@C hollow nanospheres were also exhibited a high adsorption capacity (100%) as the adsorbent for methylene blue (MB). In addition, the as-prepared Fe3O4@C hollow nanospheres can be used as the recyclable sorbent for water treatment via a simple magnetic separation.

  8. Facile Hydrothermal Synthesis of Fe3O4/C Core-Shell Nanorings for Efficient Low-Frequency Microwave Absorption.

    PubMed

    Wu, Tong; Liu, Yun; Zeng, Xiang; Cui, Tingting; Zhao, Yanting; Li, Yana; Tong, Guoxiu

    2016-03-23

    Using elliptical iron glycolate nanosheets as precursors, elliptical Fe3O4/C core-shell nanorings (NRs) [25 ± 10 nm in wall thickness, 150 ± 40 nm in length, and 1.6 ± 0.3 in long/short axis ratio] are synthesized via a one-pot hydrothermal route. The surface-poly(vinylpyrrolidone) (PVP)-protected-glucose reduction/carbonization/Ostwald ripening mechanism is responsible for Fe3O4/C NR formation. Increasing the glucose/precursor molar ratio can enhance carbon contents, causing a linear decrease in saturation magnetization (Ms) and coercivity (Hc). The Fe3O4/C NRs reveal enhanced low-frequency microwave absorption because of improvements to their permittivity and impedance matching. A maximum RL value of -55.68 dB at 3.44 GHz is achieved by Fe3O4/C NRs with 11.95 wt % C content at a volume fraction of 17 vol %. Reflection loss (RL) values (≤-20 dB) are observed at 2.11-10.99 and 16.5-17.26 GHz. Our research provides insights into the microwave absorption mechanism of elliptical Fe3O4/C core-shell NRs. Findings indicate that ring-like and core-shell nanostructures are promising structures for devising new and effective microwave absorbers.

  9. Enhancement of dispersion and adhesion of B 4 C particles in epoxy resin using direct ultrasonic excitation

    NASA Astrophysics Data System (ADS)

    Jun, Jiheon; Kim, Jaewoo; Bae, Yeonjoo; Seo, Young Soo

    2011-09-01

    Enhancement of the mechanical properties of the B 4C/epoxy composites, which is used as a neutron shield for spent nuclear fuel cask, was achieved by direct ultrasonic dispersion of the B 4C particles in the hardener using an immersed horn, while those prepared without direct ultrasonic dispersion showed insufficient adhesion as well as some agglomerates in the epoxy resin. Degrees of agglomeration and adhesion were analyzed by means of the SEM images and the FTIR peaks belong to C-C stretching mode of the hardener ring, which was lowered and flattened by van der Waals interaction between the B 4C particles and the hardener ring substituent. The tensile strength of the B 4C/epoxy composites prepared by direct ultrasonic dispersion was maintained (or increased) compared to that for the neat epoxy matrix, while those prepared without ultrasonic dispersion were degraded significantly. Consequently, direct ultrasonic dispersion process developed in this investigation could achieve uniform dispersion as well as strong adhesion of the B 4C particles in/with the epoxy matrix enhancing the material properties without any chemical treatment resulting unwanted impurities.

  10. Pharmacophore modeling, 3D-QSAR and docking study of 2-phenylpyrimidine analogues as selective PDE4B inhibitors.

    PubMed

    Tripuraneni, Naga Srinivas; Azam, Mohammed Afzal

    2016-04-07

    Pharmacophore modeling, molecular docking, and molecular dynamics (MD) simulation studies have been performed, to explore the putative binding modes of 2-phenylpyrimidine series as PDE4B selective inhibitors. A five point pharmacophore model was developed using 87 molecules having pIC50 ranging from 8.52 to 5.07. The pharmacophore hypothesis yielded a statistically significant 3D-QSAR model, with a high correlation coefficient (R(2)=0.918), cross validation coefficient (Q(2)=0.852), and F value (175) at 4 component PLS factor. The external validation indicated that our QSAR model possessed high predictive power (R(2)=0.70). The generated model was further validated by enrichment studies using the decoy test. To evaluate the effectiveness of docking protocol in flexible docking, we have selected crystallographic bound compound to validate our docking procedure as evident from root mean square deviation. A 10ns molecular dynamics simulation confirmed the docking results of both stability of the 1XMU-ligand complex and the presumed active conformation. Further, similar orientation was observed between the superposition of the conformations of 85 after MD simulation and best XP-docking pose; MD simulation and 3D-QSAR pose; best XP-docking and 3D-QSAR poses. Outcomes of the present study provide insight in designing novel molecules with better PDE4B selective inhibitory activity.

  11. Development of 1H-Pyrazolo[3,4-b]pyridines as Metabotropic Glutamate Receptor 5 Positive Allosteric Modulators.

    PubMed

    Hill, Matthew D; Fang, Haiquan; Brown, Jeffrey M; Molski, Thaddeus; Easton, Amy; Han, Xiaojun; Miller, Regina; Hill-Drzewi, Melissa; Gallagher, Lizbeth; Matchett, Michele; Gulianello, Michael; Balakrishnan, Anand; Bertekap, Robert L; Santone, Kenneth S; Whiterock, Valerie J; Zhuo, Xiaoliang; Bronson, Joanne J; Macor, John E; Degnan, Andrew P

    2016-12-08

    The metabotropic glutamate receptor 5 (mGluR5) is an attractive target for the treatment of schizophrenia due to its role in regulating glutamatergic signaling in association with the N-methyl-d-aspartate receptor (NMDAR). We describe the synthesis of 1H-pyrazolo[3,4-b]pyridines and their utility as mGluR5 positive allosteric modulators (PAMs) without inherent agonist activity. A facile and convergent synthetic route provided access to a structurally diverse set of analogues that contain neither the aryl-acetylene-aryl nor aryl-methyleneoxy-aryl elements, the predominant structural motifs described in the literature. Binding studies suggest that members of our new chemotype do not engage the receptor at the MPEP and CPPHA mGluR5 allosteric sites. SAR studies culminated in the first non-MPEP site PAM, 1H-pyrazolo[3,4-b]pyridine 31 (BMT-145027), to improve cognition in a preclinical rodent model of learning and memory.

  12. Synthesis and optical and electrochemical properties of julolidine-structured pyrido[3,4-b]indole dye.

    PubMed

    Enoki, Toshiaki; Matsuo, Keishi; Ohshita, Joji; Ooyama, Yousuke

    2017-02-01

    The julolidine-structured pyrido[3,4-b]indole dye ET-1 has been newly designed and developed as a small D-A fluorescent dye. ET-1 showed bathochromic shifts of the fluorescence band upon changing from aprotic solvents to protic solvents, as well as positive fluorescence solvatochromism. Moreover, it was found that ET-1 can form a 1 : 1 Py(N)-B complex with boron trifluoride and a hydrogen-bonded proton transfer (Py(N)-H) complex with trifluoroacetic acid, which exhibit photoabsorption and fluorescence bands at a longer wavelength region than the pristine ET-1. Based on optical (photoabsorption and fluorescence spectroscopy) and electrochemical (cyclic voltammetry) measurements, Lippert-Mataga plots, (1)H NMR spectral measurement and density functional theory (DFT) calculation, this work indicated that the Py(N)-B complex or the Py(N)-H complex is effectively formed and stable in solution. This is due to the strong Py(N)-B interaction or Py(N)-hydrogen-bond, which can be attributed to the enhanced basicity or the accumulated electron density on the nitrogen atom of the pyridine ring caused by the introduction of a julolidine (quinolizidine) moiety as a strong electron-donating group. We propose that the D-A-type dye ET-1 based on the julolidine-structured pyrido[3,4-b]indole possesses the ability to act as a calorimetric and fluorescent sensor for Brønsted and Lewis acids.

  13. The Phosphatase PP4c Controls Spindle Orientation to Maintain Proliferative Symmetric Divisions in the Developing Neocortex

    PubMed Central

    Xie, Yunli; Jüschke, Christoph; Esk, Christopher; Hirotsune, Shinji; Knoblich, Juergen A.

    2013-01-01

    Summary In the developing neocortex, progenitor cells expand through symmetric division before they generate cortical neurons through multiple rounds of asymmetric cell division. Here, we show that the orientation of the mitotic spindle plays a crucial role in regulating the transition between those two division modes. We demonstrate that the protein phosphatase PP4c regulates spindle orientation in early cortical progenitor cells. Upon removing PP4c, mitotic spindles fail to orient in parallel to the neuroepithelial surface and progenitors divide with random orientation. As a result, their divisions become asymmetric and neurogenesis starts prematurely. Biochemical and genetic experiments show that PP4c acts by dephosphorylating the microtubule binding protein Ndel1, thereby enabling complex formation with Lis1 to form a functional spindle orientation complex. Our results identify a key regulator of cortical development and demonstrate that changes in the orientation of progenitor division are responsible for the transition between symmetric and asymmetric cell division. PMID:23830831

  14. [Continuous cell subline A4C2/9K and its application to the african swine fever virus study].

    PubMed

    Balysheva, V I; Prudnikova, E Yu; Galnbek, T V; Balyshev, V M

    2015-01-01

    A new continuous cell subline A4C2/9K highly sensitive to the african swine fever virus (ASFV) was prepared. All the tested ASFV strains isolated in the Russian Federation in 2008-2013 proliferated in this cell culture exhibiting hemadsorption and accumulated at a titer of up to 6.5 Ig HAU50/cm3. The cell culture A4C2/9K can be used for ASFV isolation or determination of its infectious activity and serotype identity. The culture versions of the ASFV strain Stavropol 01/08 at passages 24 and 33 in the cell culture A4C2/9K lost their pathogenicity for pigs.

  15. Phase 4B: Commissioning

    DTIC Science & Technology

    2007-11-02

    to discover any single-valued relation between the results of small-scale loading tests and of the settlement of large foundations on stratified...offshore engineering. In a jackup platform, the three legs apply cyclic loads of the order of ten thousand tonnes to spud cans bearing on a sea bed...work has led directly to a revised design approach. Foundation fixity now is described by a yield locus rather than by " bearing capacity factors". The

  16. Og4C3 circulating antigen: a marker of infection and adult worm burden in Wuchereria bancrofti filariasis.

    PubMed

    Chanteau, S; Moulia-Pelat, J P; Glaziou, P; Nguyen, N L; Luquiaud, P; Plichart, C; Martin, P M; Cartel, J L

    1994-07-01

    Og4C3 circulating filarial antigen was detected in the sera of 94.5% (259/274) of microfilaremic patients, 32% (239/751) of persons with presumption of filariasis, and 23% (11/48) of chronic filariasis patients. The antigen level was correlated with the microfilariae (Mf) density and patient age (P < .01). It remained stable in patients treated with microfilaricidal drugs. Og4C3 antigen, undetectable in Mf culture media, was demonstrated to be a rare somatic Mf antigen. It appears to be an excreted or secreted antigen from adult filaria. It could be used as a marker of infection and an indicator of adult worm burden.

  17. The histone demethylase KDM4B interacts with MyoD to regulate myogenic differentiation in C2C12 myoblast cells.

    PubMed

    Choi, Jang Hyun; Song, Young Joon; Lee, Hansol

    2015-01-24

    Enzymes that mediate posttranslational modifications of histone and nonhistone proteins have been implicated in regulation of skeletal muscle differentiation. However, functions of histone demethylases that could counter the actions of H3-K9 specific histone methyltransferases remain still obscure. Here we present evidences that KDM4B histone demethylase regulates expression of myogenic regulators such as MyoD and thereby controls myogenic differentiation of C2C12 myoblast cells. We demonstrate that expression of KDM4B gradually increases during myogenic differentiation and depletion of KDM4B using shRNA results in inhibition of differentiation in C2C12 myoblast cells, which is correlated with decreased expression of MyoD and myogenin. In addition, we find that KDM4B shRNA represses expression of MyoD promoter-driven luciferase reporter and exogenous expression of MyoD rescues myogenic potential in KDM4B-depleted myoblast cells. We further show that KDM4B interacts with MyoD, binds to MyoD and myogenin promoters in vivo, and finally, is involved in demethylation of tri-methylated H3-K9 on promoters of MyoD and myogenin. Taken together, our data suggest that KDM4B plays key roles in myogenic differentiation of C2C12 cells, presumably by its function as a H3-K9 specific histone demethylase.

  18. Small GTPase Rab4b participates in the gene transcription of 20-hydroxyecdysone and insulin pathways to regulate glycogen level and metamorphosis.

    PubMed

    Hou, Li; Cai, Mei-Juan; Liu, Wen; Song, Qian; Zhao, Xiao-Fan

    2012-11-01

    The insulin and 20-hydroxyecdysone (20E) pathways coordinately regulate insect growth and metamorphosis. However, the molecular mechanism of the interaction of these two pathways in regulating insect development is not well understood. In the present study, we found that a small GTPase Rab4b from a lepidopteran insect Helicoverpa armigera participates in gene transcription in the two pathways. The results show that RNA interference of Rab4b in larvae results in a decrease in glycogen levels, small pupae, abnormal metamorphic transition, or larval death. The molecular mechanisms are demonstrated that knockdown of Rab4b in the larvae suppresses the transcription of glycogen synthase (GS), as well as the metamorphic-initiating factor (Br) and hormone receptor 3 (HR3), but increases the transcription of Forkhead box class O (FOXO). Further studies in the cell line confirm that Rab4b is necessary for gene transcription in the insulin and 20E pathways. Rab4b locates in the cytoplasm and takes part in regulation on FOXO cytoplasmic location by insulin induction, but travels toward the cell membrane upon 20E induction without affecting the FOXO location. The transcription of Rab4b could be upregulated by insulin injection or glucose feeding to the larvae, but not by 20E or juvenile hormone analogy methoprene. Our data suggest that Rab4b takes part in metamorphosis by regulating gene transcription and glycogen level in the insulin and 20E pathways.

  19. A novel read-through transcript JMJD7-PLA2G4B regulates head and neck squamous cell carcinoma cell proliferation and survival

    PubMed Central

    Cheng, Yingduan; Wang, Yi; Li, Jiong; Chang, Insoon; Wang, Cun-Yu

    2017-01-01

    Recent findings on the existence of oncogenic fusion genes in a wide array of solid tumors, including head and neck squamous cell carcinoma (HNSCC), suggests that fusion genes have become attractive targets for cancer diagnosis and treatment. In this study, we showed for the first time that a read-through fusion gene JMJD7-PLA2G4B is presented in HNSCC, splicing neighboring jumonji domain containing 7 (JMJD7) and phospholipase A2, group IVB (PLA2G4B) genes together. Ablation of JMJD7-PLA2G4B significantly inhibited proliferation of HNSCC cells by promoting G1 cell cycle arrest and increased starvation-induced cell death compared to JMJD7-only knockdown HNSCC cells. Mechanistically, we found that JMJD7-PLA2G4B modulates phosphorylation of Protein Kinase B (AKT) to promote HNSCC cell survival. Moreover, JMJD7-PLA2G4B also regulated an E3 ligase S-phase kinase-associated protein 2 (SKP2) to control the cell cycle progression from G1 phase to S phase by inhibiting Cyclin-dependent kinase inhibitor 1 (p21) and 1B (p27) expression. Our study provides novel insights into the oncogenic control of JMJD7-PLA2G4B in HNSCC cell proliferation and survival, and suggests that JMJD7-PLA2G4B may serve as an important therapeutic target and prognostic marker for HNSCC development and progression. PMID:28030848

  20. Sites within the complement C3b/C4b receptor important for the specificity of ligand binding.

    PubMed Central

    Krych, M; Hourcade, D; Atkinson, J P

    1991-01-01

    Cysteine-rich repeated units of 40-70 amino acids are building blocks of many mammalian proteins, including 12 proteins of the complement system. Human complement arranged motifs, designated short consensus repeats (SCRs), which constitute the entire extracellular portion of this protein. Klickstein et al. [Klickstein, L. B., Bartow, T. J., Miletic, V., Rabson, L. D., Smith, J. A. & Fearon, D. T. (1988) J. Exp. Med. 168, 1699-1717 (abstr.)] localized a C4b binding domain to SCR-1 and/or SCR-2 and a C3b binding domain to SCR-8 and/or SCR-9. These SCRs bind different ligands, although SCR-1 and SCR-8 are 55% homologous and SCR-2 and SCR-9 are 70% homologous. To examine if one or two SCRs are required for ligand binding and to define sites within the SCRs that determine specificity of binding, mutagenesis analysis of a truncated, secreted form of CR1, called CR1-4 by Hourcade et al. [Hourcade, D., Meisner, D. R., Atkinson, J. P. & Holers, V. M. (1988) J. Exp. Med. 168, 1255-1270], was undertaken. The latter, composed of the first eight and one-half amino-terminal SCRs of CR1, efficiently bound C4b but not iC3. SCR-1 and SCR-2 were necessary for this interaction. Analysis of the mutant CR1-4 proteins, in which amino acids in SCR-1 and SCR-2 were substituted a few at a time with the homologous amino acids of SCR-8 and SCR-9, led to the identification of one amino acid in SCR-1 and three amino acids in SCR-2 important for C4b binding. Furthermore, five amino acids at the end of SCR-9, if placed in the homologous positions of SCR-2, conferred iC3 binding and are likely essential for ligand binding activity of SCR-8 and SCR-9. This iC3 binding occurred only if SCR-1 was present, indicating that two contiguous SCRs are necessary for this interaction. These results provide identification of amino acids within SCRs that are important for ligand binding. Images PMID:1827918

  1. Integrated Avionics Computerized Test Station and Component (F-15) Career Ladder AFS 326X4B. Occupational Survey Report.

    DTIC Science & Technology

    1982-06-01

    K OOZ"’~- OAC’O- WCWM 00 Coo 0% co coGoaoCO0Lin ’ O a 0 -4 %0 w %a E- 0 0 0C/CJ MEl-HomomC)U QCJC.a) u4c uu 31 COMPARISON OF SURVEY DATA TO AFR 39-1...officials. The survey instrument was developed by Captain Gary K . Patterson, Inventory Development Specialist. Mr Bob Vance and Ms Becky Hernandez...types or clusters described above. 8 ~ O DUE-IN-FROM MAINTENANCE (DIFM) MONITORS (GRP034, N=6) SHIFT SUPERVISORS (GRP073, N5 SUPERVISION AND SHOP NCOICs

  2. Plasma membrane calcium ATPase 4b inhibits nitric oxide generation through calcium-induced dynamic interaction with neuronal nitric oxide synthase.

    PubMed

    Duan, Wenjuan; Zhou, Juefei; Li, Wei; Zhou, Teng; Chen, Qianqian; Yang, Fuyu; Wei, Taotao

    2013-04-01

    The activation and deactivation of Ca(2+)- and calmodulindependent neuronal nitric oxide synthase (nNOS) in the central nervous system must be tightly controlled to prevent excessive nitric oxide (NO) generation. Considering plasma membrane calcium ATPase (PMCA) is a key deactivator of nNOS, the present investigation aims to determine the key events involved in nNOS deactivation of by PMCA in living cells to maintain its cellular context. Using time-resolved Förster resonance energy transfer (FRET), we determined the occurrence of Ca(2+)-induced protein-protein interactions between plasma membrane calcium ATPase 4b (PMCA4b) and nNOS in living cells. PMCA activation significantly decreased the intracellular Ca(2+) concentrations ([Ca(2+)]i), which deactivates nNOS and slowdowns NO synthesis. Under the basal [Ca(2+)]i caused by PMCA activation, no protein-protein interactions were observed between PMCA4b and nNOS. Furthermore, both the PDZ domain of nNOS and the PDZ-binding motif of PMCA4b were essential for the protein-protein interaction. The involvement of lipid raft microdomains on the activity of PMCA4b and nNOS was also investigated. Unlike other PMCA isoforms, PMCA4 was relatively more concentrated in the raft fractions. Disruption of lipid rafts altered the intracellular localization of PMCA4b and affected the interaction between PMCA4b and nNOS, which suggest that the unique lipid raft distribution of PMCA4 may be responsible for its regulation of nNOS activity. In summary, lipid rafts may act as platforms for the PMCA4b regulation of nNOS activity and the transient tethering of nNOS to PMCA4b is responsible for rapid nNOS deactivation.

  3. Targeting a novel cancer-driving protein (LAPTM4B-35) by a small molecule (ETS) to inhibit cancer growth and metastasis

    PubMed Central

    Li, Maojin; Zhou, Rouli; Shan, Yi; Li, Li; Wang, Lin; Liu, Gang

    2016-01-01

    Our previous studies demonstrated that LAPTM4B-35 is overexpressed in a variety of solid cancers including hepatocellular carcinoma (HCC), and is an independent factor for prognosis. LAPTM4B-35 overexpression causes carcinogenesis and enhances cancer growth, metastasis and multidrug resistance, and thus may be a candidate for therapeutic targeting. The present study shows ethylglyoxal bisthiosemicarbazon (ETS) has effective anticancer activity through LAPTM4B-35 targeting. Bel-7402 and HepG2 cell lines from human HCC were used as cell models in which LAPTM4B-35 is highly expressed, and a human fetal liver cell line was used as a control. The results showed ETS has a specific and pronounced lethal effect on HCC cells, but not on fetal liver cells in culture. ETS also attenuated growth and metastasis of human HCC xenograft in nude mice, and extended the life span of mice with HCC. ETS induced HCC cell apoptosis, and upregulated a large number of proapoptotic genes and downregulated antiapoptotic genes. When endogenous overexpression of LAPTM4B-35 was knocked down with RNAi, the killing effect of ETS on HepG2 cells was significantly attenuated. ETS also inhibited phosphorylation of LAPTM4B-35 Tyr285, which involves in activation of the PI3K/Akt signaling pathway induced by LAPTM4B-35 overexpression. In addition, the induction of alterations in quantity of c-Myc, Bcl-2, Bax, cyclinD1 and Akt-p molecules in HepG2 cells by LAPTM4B-35 overexpression could be reversed by ETS. Conclusion: ETS is a promising candidate for treatment of HCC through LAPTM4B-35 protein targeting. PMID:27542271

  4. eIF4B is a convergent target and critical effector of oncogenic Pim and PI3K/Akt/mTOR signaling pathways in Abl transformants

    PubMed Central

    Chen, Ke; Yang, Jianling; Li, Jianning; Wang, Xuefei; Chen, Yuhai; Huang, Shile; Chen, Ji-Long

    2016-01-01

    Activation of eIF4B correlates with Abl-mediated cellular transformation, but the precise mechanisms are largely unknown. Here we show that eIF4B is a convergent substrate of JAK/STAT/Pim and PI3K/Akt/mTOR pathways in Abl transformants. Both pathways phosphorylated eIF4B in Abl-transformed cells, and such redundant regulation was responsible for the limited effect of single inhibitor on Abl oncogenicity. Persistent inhibition of one signaling pathway induced the activation of the other pathway and thereby restored the phosphorylation levels of eIF4B. Simultaneous inhibition of the two pathways impaired eIF4B phosphorylation more effectively, and synergistically induced apoptosis in Abl transformed cells and inhibited the growth of engrafted tumors in nude mice. Similarly, the survival of Abl transformants exhibited a higher sensitivity to the pharmacological inhibition, when combined with the shRNA-based silence of the other pathway. Interestingly, such synergy was dependent on the phosphorylation status of eIF4B on Ser422, as overexpression of eIF4B phosphomimetic mutant S422E in the transformants greatly attenuated the synergistic effects of these inhibitors on Abl oncogenicity. In contrast, eIF4B knockdown sensitized Abl transformants to undergo apoptosis induced by the combined blockage. Collectively, the results indicate that eIF4B integrates the signals from Pim and PI3K/Akt/mTOR pathways in Abl-expressing leukemic cells, and is a promising therapeutic target for such cancers. PMID:26848623

  5. LAPTM4B-35, a Cancer-Related Gene, Is Associated with Poor Prognosis in TNM Stages I-III Gastric Cancer Patients

    PubMed Central

    Wu, Xiaojiang; Zhang, Lianhai; Xing, Xiaofang; Wang, Xiaohong; Hu, Ying; Du, Hong; Li, Lin; Li, Shen; Zhou, Rouli; Wen, Xian-Zi; Ji, Jia-Fu

    2015-01-01

    Background Lysosome-associated transmembrane protein 4β-35 (LAPTM4B-35), a member of the mammalian 4-tetratransmembrane spanning protein superfamily, has been reported to be overexpressed in several cancers. However the expression of LAPTM4B-35 and its role in the progression of gastric cancer (GC) remains unknown. The aim of this study was to investigate LAPTM4B-35 expression in GC, its potential relevance to clinicopathologic parameters and role of LAPTM4B-35 during gastric carcinogenesis. Methods In the present study, paraffin-embedded specimens with GC (n = 240, including 180 paired specimens) and 24 paired fresh frozen tissues were analyzed. qRT-PCR and immunohistochemistry (IHC) were used to analyze the expression of LAPTM4B-35 in GC. The effects of LAPTM4B-35 on GC cell proliferation, migration and invasion were determined by overexpression and knockdown assays. Results IHC showed that LAPTM4B-35 was expressed in 68.3% (123/180) of GC tissues, while in 16.1% (29/180) of their paired adjacent noncancerous gastric tissues (P = 0.000). LAPTM4B-35 mRNA levels in GC tissues were also significantly elevated when compared with their paired adjacent noncancerous tissues (P = 0.017). Overexpression of LAPTM4B-35 was significantly associated with degree of differentiation, depth of invasion, lymphovascular invasion and lymph node metastasis (P<0.05). Kaplan-Meier survival curves revealed that patients with LAPTM4B-35 expression had a significant decrease in overall survival (OS) in stages I-III GC patients (P = 0.006). Multivariate analysis showed high expression of LAPTM4B-35 was an independent prognostic factor for OS in stage I-III GC patients (P = 0.025). Conclusion These findings indicate that LAPTM4B-35 overexpression may be related to GC progression and poor prognosis, and thus may serve as a new prediction marker of prognosis in GC patients. PMID:25849595

  6. Synthesis and characterization of thieno[3,4-b]pyrazine-based terthienyls: tunable precursors for low band gap conjugated materials.

    PubMed

    Schwiderski, Ryan L; Rasmussen, Seth C

    2013-06-07

    Synthetic methods have been developed for the preparation of new 2,3-dihalo- and 2,3-ditriflato-5,7-bis(2-thienyl)thieno[3,4-b]pyrazines. From these reactive intermediates, a variety of new 2,3-difunctionalized 5,7-bis(2-thienyl)thieno[3,4-b]pyrazines have been produced as precursors to conjugated materials. Structural, electronic, and optical characterization of these new analogues illustrate the extent to which the electronic nature of the functional groups can be used to tune the electronic properties of these thieno[3,4-b]pyrazine-based terthienyl units.

  7. Purification of human C4b-binding protein and formation of its complex with vitamin K-dependent protein S.

    PubMed Central

    Dahlbäck, B

    1983-01-01

    C4b-binding protein was purified from human plasma in high yield by a simple procedure involving barium citrate adsorption and two subsequent chromatographic steps. Approx. 80% of plasma C4b-binding protein was adsorbed on the barium citrate, presumably because of its complex-formation with vitamin K-dependent protein S. The purified C4b-binding protein had a molecular weight of 570 000, as determined by ultracentrifugation, and was composed of about eight subunits (Mr approx. 70 000). Uncomplexed plasma C4b-binding protein was purified from the supernatant after barium citrate adsorption. On sodium dodecyl sulphate/polyacrylamide-gel electrophoresis in non-reducing conditions and on agarose-gel electrophoresis it appeared as a doublet, indicating two forms differing slightly from each other in molecular weight and net charge. The protein band with the higher molecular weight in the doublet corresponded to the C4b-binding protein purified from the barium citrate eluate. Complex-formation between protein S and C4b-binding protein was studied in plasma, and in a system with purified components, by an agarose-gel electrophoresis technique. Protein S was found to form a 1:1 complex with the higher-molecular-weight form of C4b-binding protein, whereas the lower-molecular-weight form of C4b-binding protein did not bind protein S. The KD for the C4b-binding protein-protein S interaction in a system with purified components was approx. 0.9 X 10(-7) M. Rates of association and dissociation at 37 degrees C were low, namely about 1 X 10(3) M-1 . S-1 and 1.8 X 10(-4)-4.5 X 10(-4) S-1 respectively. In human plasma free protein S and free higher-molecular-weight C4b-binding protein were in equilibrium with the C4b-binding protein-protein S complex. Approx. 40% of both proteins existed as free proteins. From equilibrium data in plasma a KD of about 0.7 X 10(-7) M was calculated for the C4b-binding protein-protein S interaction. Images Fig. 2. Fig. 3. PMID:6223625

  8. Monte Carlo Simulation of Electron Beams for Radiotherapy - EGS4, MCNP4b and GEANT3 Intercomparison

    NASA Astrophysics Data System (ADS)

    Trindade, A.; Rodrigues, P.; Alves, C.; Chaves, A.; Lopes, M. C.; Oliveira, C.; Peralta, L.

    In medical radiation physics, an increasing number of Monte Carlo codes are being used, which requires intercomparison between them to evaluated the accuracy of the simulated results against benchmark experiments. The Monte Carlo code EGS4, commonly used to simulate electron beams from medical linear accelerators, was compared with GEANT3 and MCNP4b. Intercomparison of electron energy spectra, angular and spatial distribution were carried out for the Siemens KD2 linear accelerator, at beam energies of 10 and 15 MeV for a field size of 10x10 cm2. Indirect validation was performed against electron depth doses curves and beam profiles measured in a MP3-PTW water phantom using a Markus planar chamber. Monte Carlo isodose lines were reconstructed and compared to those from commercial treatment planning systems (TPS's) and with experimental data.

  9. Conserved patterns hidden within group A Streptococcus M protein hypervariability recognize human C4b-binding protein

    SciTech Connect

    Buffalo, Cosmo Z.; Bahn-Suh, Adrian J.; Hirakis, Sophia P.; Biswas, Tapan; Amaro, Rommie E.; Nizet, Victor; Ghosh, Partho

    2016-09-05

    No vaccine exists against group A Streptococcus (GAS), a leading cause of worldwide morbidity and mortality. A severe hurdle is the hypervariability of its major antigen, the M protein, with >200 different M types known. Neutralizing antibodies typically recognize M protein hypervariable regions (HVRs) and confer narrow protection. In stark contrast, human C4b-binding protein (C4BP), which is recruited to the GAS surface to block phagocytic killing, interacts with a remarkably large number of M protein HVRs (apparently ~90%). Such broad recognition is rare, and we discovered a unique mechanism for this through the structure determination of four sequence-diverse M proteins in complexes with C4BP. The structures revealed a uniform and tolerant ‘reading head’ in C4BP, which detected conserved sequence patterns hidden within hypervariability. Our results open up possibilities for rational therapies that target the M–C4BP interaction, and also inform a path towards vaccine design.

  10. THE TRANSIT LIGHT CURVE PROJECT. XI. SUBMILLIMAGNITUDE PHOTOMETRY OF TWO TRANSITS OF THE BLOATED PLANET WASP-4b

    SciTech Connect

    Winn, Joshua N.; Carter, Joshua A.; Beatty, Thomas; Holman, Matthew J.; Torres, Guillermo; Osip, David J.

    2009-04-15

    We present photometry of two transits of the giant planet WASP-4b with a photometric precision of 400-800 parts per million and a time sampling of 25-40 s. The two midtransit times are determined to within 6 s. Together with previously published times, the data are consistent with a constant orbital period, giving no compelling evidence for period variations that would be produced by a satellite or additional planets. Analysis of the new photometry, in combination with stellar-evolutionary modeling, gives a planetary mass and radius of 1.237 {+-} 0.064 M {sub Jup} and 1.365 {+-} 0.021 R {sub Jup}, respectively. The planet is 15% larger than expected based on previously published models of solar-composition giant planets. With data of the quality presented here, the detection of transits of a 'super-Earth' of radius 1.75 R {sub +} would have been possible.

  11. Evaluation of a 50-MV Photon Therapy Beam from a Racetrack Microtron Using MCNP4B Monte Carlo Code

    NASA Astrophysics Data System (ADS)

    Gudowska, I.; Sorcini, B.; Svensson, R.

    High energy photon therapy beam from the 50 MV racetrack microtron has been evaluated using the Monte Carlo code MCNP4B. The spatial and energy distribution of photons, radial and depth dose distributions in the phantom are calculated for the stationary and scanned photon beams from different targets. The calculated dose distributions are compared to the experimental data using a silicon diode detector. Measured and calculated depth-dose distributions are in fairly good agreement, within 2-3% for the positions in the range 2-30 cm in the phantom, whereas the larger discrepancies up to 10% are observed in the dose build-up region. For the stationary beams the differences in the calculated and measured radial dose distributions axe about 2-10%.

  12. ORBITAL ORIENTATIONS OF EXOPLANETS: HAT-P-4b IS PROGRADE AND HAT-P-14b IS RETROGRADE

    SciTech Connect

    Winn, Joshua N.; Albrecht, Simon; Howard, Andrew W.; Marcy, Geoffrey W.; Isaacson, Howard; Johnson, John Asher; Crepp, Justin R.; Morton, Timothy D.; Shporer, Avi; Bakos, Gaspar A.; Hartman, Joel D.; Holman, Matthew J.

    2011-02-15

    We present observations of the Rossiter-McLaughlin effect for two exoplanetary systems, revealing the orientations of their orbits relative to the rotation axes of their parent stars. HAT-P-4b is prograde, with a sky-projected spin-orbit angle of {lambda} = -4.9 {+-} 11.9 deg. In contrast, HAT-P-14b is retrograde, with {lambda} = 189.1 {+-} 5.1 deg. These results conform with a previously noted pattern among the stellar hosts of close-in giant planets: hotter stars have a wide range of obliquities and cooler stars have low obliquities. This, in turn, suggests that three-body dynamics and tidal dissipation are responsible for the short-period orbits of many exoplanets. In addition, our data revealed a third body in the HAT-P-4 system, which could be a second planet or a companion star.

  13. The Use of Spray-Dried Mn3O4/C Composites as Electrocatalysts for Li–O2 Batteries

    PubMed Central

    Yang, Hong-Kai; Chin, Chih-Chun; Chen, Jenn-Shing

    2016-01-01

    The electrocatalytic activities of Mn3O4/C composites are studied in lithium–oxygen (Li–O2) batteries as cathode catalysts. The Mn3O4/C composites are fabricated using ultrasonic spray pyrolysis (USP) with organic surfactants as the carbon sources. The physical and electrochemical performance of the composites is characterized by X-ray diffraction, scanning electron microscopy, particle size analysis, Brunauer–Emmett–Teller (BET) measurements, elemental analysis, galvanostatic charge–discharge methods and rotating ring-disk electrode (RRDE) measurements. The electrochemical tests demonstrate that the Mn3O4/C composite that is prepared using Trition X-114 (TX114) surfactant has higher activity as a bi-functional catalyst and delivers better oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic performance in Li–O2 batteries because there is a larger surface area and particles are homogeneous with a meso/macro porous structure. The rate constant (kf) for the production of superoxide radical (O2•−) and the propylene carbonate (PC)-electrolyte decomposition rate constant (k) for M3O4/C and Super P electrodes are measured using RRDE experiments and analysis in the 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF6)/PC electrolyte. The results show that TX114 has higher electrocatalytic activity for the first step of ORR to generate O2•− and produces a faster PC-electrolyte decomposition rate. PMID:28335331

  14. 75 FR 34983 - Order (1) Pursuant to Section 4(c) of the Commodity Exchange Act, Permitting the Kansas City...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-21

    ... of Trade Clearing Corporation To Clear Over-the-Counter Wheat Calendar Swaps and (2) Pursuant to... organization (DCO), requested permission to clear over-the-counter (OTC) swap agreements (swaps) in wheat... section 4(c) of the Act.\\3\\ The order would grant KCBTCC approval to clear OTC wheat calendar swaps,...

  15. Resonant soft x-ray reflectivity of Me/B4C multilayers near the boron K edge

    SciTech Connect

    Ksenzov, Dmitriy; Schlemper, Christoph; Pietsch, Ullrich

    2010-09-01

    Energy dependence of the optical constants of boron carbide in the short period Ru/B4C and Mo/B4C multilayers (MLs) are evaluated from complete reflectivity scans across the boron K edge using the energy-resolved photon-in-photon-out method. Differences between the refractive indices of the B4Cmaterial inside and close to the surface are obtained from the peak profile of the first order ML Bragg peak and the reflection profile near the critical angle of total external reflection close to the surface. Where a Mo/B4C ML with narrow barrier layers appears as a homogeneous ML at all energies, a Ru/B4C ML exhibits another chemical nature of boron at the surface compared to the bulk. From evaluation of the critical angle of total external reflection in the energy range between 184 and 186 eV, we found an enriched concentration of metallic boron inside the Ru-rich layer at the surface, which is not visible in other energy ranges.

  16. 12 CFR 225.104 - “Services” under section 4(c)(1) of Bank Holding Company Act.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false âServicesâ under section 4(c)(1) of Bank Holding Company Act. 225.104 Section 225.104 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF... purchasing installment paper suitable for investment by banking subsidiaries of Holding Company A....

  17. Additive synthesis with DIASS-M4C on Argonne National Laboratory`s IBM POWERparallel System (SP)

    SciTech Connect

    Kaper, H.; Ralley, D.; Restrepo, J.; Tiepei, S.

    1995-12-31

    DIASS-M4C, a digital additive instrument was implemented on the Argonne National Laboratory`s IBM POWER parallel System (SP). This paper discusses the need for a massively parallel supercomputer and shows how the code was parallelized. The resulting sounds and the degree of control the user can have justify the effort and the use of such a large computer.

  18. Fabrication, structure, and properties of Fe3O4@C encapsulated with YVO4:Eu3+ composites

    NASA Astrophysics Data System (ADS)

    Shi, Jianhui; Tong, Lizhu; Liu, Deming; Yang, Hua

    2012-03-01

    The use of carbon shells offers many advantages in surface coating or surface modification due to their surface with activated carboxyl and carbonyl groups. In this study, the Fe3O4@C@YVO4:Eu3+ composites were prepared through a simple sol-gel process. Reactive carbon interlayer was introduced as a key component, which separates lanthanide-based luminescent component from the magnetite, more importantly, it effectively prevent oxidation of the Fe3O4 core during the whole preparation process. The morphology, structure, magnetic, and luminescent properties of the composites were characterized by transmission electron microscopy (TEM), high-resolution TEM, X-ray diffraction, X-ray photoelectron spectra, VSM, and photoluminescent spectrophotometer. As a result, the Fe3O4@C/YVO4:Eu3+ composites with well-crystallized and core-shell structure were prepared and the YVO4:Eu3+ luminescent layer decorating the Fe3O4@C core-shell microspheres are about 10 nm. In addition, the Fe3O4@C@YVO4:Eu3+ composites have the excellent magnetic and luminescent properties, which allow them great potential for bioapplications such as magnetic bioseparation, magnetic resonance imaging, and drug/gene delivery.

  19. Learning Electrical Circuits: The Effects of the 4C-ID Instructional Approach in the Acquisition and Transfer of Knowledge

    ERIC Educational Resources Information Center

    Melo, Mário; Miranda, Guilhermina Lobato

    2015-01-01

    This study was designed to investigate the effects of two instructional approaches (4C-ID versus conventional) on learners' knowledge-acquisition and learning transfer of the electrical circuits content in Physics. Participants were 129 9th graders from a secondary school in Lisbon, M = 14.3 years, SD = 0.54. The participants were divided in two…

  20. Rapid Polyol-Assisted Microwave Synthesis of Nanocrystalline LiFePO4/C Cathode for Lithium-Ion Batteries.

    PubMed

    Paul, Baboo Joseph; Gim, Jihyeon; Baek, Sora; Kang, Jungwon; Song, Jinju; Kim, Sungjin; Kim, Jaekook

    2015-08-01

    Nanocrystalline LiFePO4/C has been synthesized under a very short period of time (90 sec) using a polyol-assisted microwave heating synthesis technique. The X-ray diffraction (XRD) data indicates that the rapidly synthesized materials correspond to phase pure olivine. Post-annealing of the as-prepared sample at 600 °C in argon atmosphere yields highly crystalline LiFePO4/C. The morphology of the samples studied using scanning electron microscopy (SEM) reveals the presence of secondary particles formed from aggregation of primary particles in the range of 30-50 nm. Transmission electron microscopy (TEM) images reveal a thin carbon layer coating on the surface of the primary particle. The charge/discharge studies indicate that the as-prepared and annealed LiFePO4/C samples delivered initial discharge capacities of 126 and 160 mA h g-1, respectively, with good capacity retentions at 0.05 mA cm-2 current densities. The post-annealing process indeed improves the crystallinity of the LiFePO4 nanocrystals, which enhances the electrode performance of LiFePO4/C.

  1. Preparation of V-Doped LiFePO4/C as the Optimized Cathode Material for Lithium Ion Batteries.

    PubMed

    Sun, Pingping; Zhang, Haiyang; Shen, Kai; Fan, Qi; Xu, Qingyu

    2015-04-01

    LiFe1-x,Vx,PO4/C composites were synthesized by solid state reaction. The effect of carbon coating and V doping on the performance of LiFePO4 has been systematically investigated by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), charge/discharge and cyclic voltammetry (CV) measurement. The results show that carbon coating and proper amount of V incorporation do not significantly change the host crystal structure of LiFePO4, while the electrochemical performance of LiFePO4 can be significantly improved. Particularly, the LiFe0.96V0.04PO4/C exhibits the best performance with a specific discharge capacity of 105.5 mA h/g at 5.0 C, 90.3 mA h/g at 10 C and 66.7 mA h/g at 30 C with stable cycle performance, which is significantly improved compared with the pure LiFePO4/C. The cyclic voltammograms result reveals that V doping could decrease the resistance of LiFePO4/C composite electrode drastically and improve its reversibility.

  2. 12 CFR 225.104 - “Services” under section 4(c)(1) of Bank Holding Company Act.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (REGULATION Y) Regulations Financial Holding Companies Interpretations § 225.104 “Services” under section 4(c... payroll, life insurance and budget loan installment account. (2) In the second case, Corporation Y, a..., who made time sales and desired to convert their time sales paper into cash; but Corporation Y made...

  3. 12 CFR 225.104 - “Services” under section 4(c)(1) of Bank Holding Company Act.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... (REGULATION Y) Regulations Financial Holding Companies Interpretations § 225.104 “Services” under section 4(c... payroll, life insurance and budget loan installment account. (2) In the second case, Corporation Y, a..., who made time sales and desired to convert their time sales paper into cash; but Corporation Y made...

  4. Constraints on Asian and European sources of methane from CH4-C2H6-CO correlations in Asian outflow

    NASA Astrophysics Data System (ADS)

    Xiao, Yaping; Jacob, Daniel J.; Wang, James S.; Logan, Jennifer A.; Palmer, Paul I.; Suntharalingam, Parvadha; Yantosca, Robert M.; Sachse, Glen W.; Blake, Donald R.; Streets, David G.

    2004-08-01

    Aircraft observations of Asian outflow from the Transport and Chemical Evolution Over the Pacific (TRACE-P) aircraft mission over the NW Pacific (March and April 2001) show large CH4 enhancements relative to background, as well as strong CH4-C2H6-CO correlations that provide signatures of regional sources. We apply a global chemical transport model simulation of the CH4-C2H6-CO system for the TRACE-P period to interpret these observations in terms of CH4 sources and to explore in particular the unique constraints from the CH4-C2H6-CO correlations. We use as a priori a global CH4 source inventory constrained with National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory (CMDL) surface observations [Wang et al., 2004]. We find that the observed CH4 concentration enhancements and CH4-C2H6-CO correlations in Asian outflow in TRACE-P are determined mainly by anthropogenic emissions from China and Eurasia (defined here as Europe and eastern Russia), with only little contribution from tropical sources (wetlands and biomass burning). The a priori inventory overestimates the observed CH4 enhancements and shows regionally variable biases for the CH4/C2H6 slope. The CH4/CO slopes are simulated without significant bias. Matching both the observed CH4 enhancements and the CH4-C2H6-CO slopes in Asian outflow requires increasing the east Asian anthropogenic source of CH4, and decreasing the Eurasian anthropogenic source, by at least 30% for both. The need to increase the east Asian source is driven by the underestimate of the CH4/C2H6 slope in boundary layer Chinese outflow. The Streets et al. [2003] anthropogenic emission inventory for east Asia fits this constraint by increasing CH4 emissions from that region by 40% relative to the a priori, largely because of higher livestock and landfill source estimates. Eurasian sources (mostly European) then need to be reduced by 30-50% from the a priori value of 68 Tg yr-1. The decrease of

  5. Facile preparation of magnetic mesoporous Fe3O4/C/Cu composites as high performance Fenton-like catalysts

    NASA Astrophysics Data System (ADS)

    Li, Keyan; Zhao, Yongqin; Janik, Michael J.; Song, Chunshan; Guo, Xinwen

    2017-02-01

    Fe-Cu composites with different compositions and morphologies were synthesized by a hydrothermal method combined with precursor thermal transformation. γ-Fe2O3/CuO and α-Fe2O3/CuO were obtained by calcining the Fe and Cu tartrates under air atmosphere at 350 °C and 500 °C, respectively, while Fe3O4/C/Cu was obtained by calcining the tartrate precursor under N2 atmosphere at 500 °C. The Fe3O4/C/Cu composite possessed mesoporous structure and large surface area up to 133 m2 g-1. The Fenton catalytic performance of Fe3O4/C/Cu composite was closely related to the Fe/Cu molar ratio, and only proper amounts of Fe and Cu exhibited a synergistic enhancement in Fenton catalytic activity. Cu inclusion reduced Fe3+ to Fe2+, which accelerated the Fe3+/Fe2+ cycles and favored H2O2 decomposition to produce more hydroxyl radicals for methylene blue (MB) oxidation. Due to the photo-reduction of Fe3+ and Cu2+, the Fenton catalytic performance was greatly improved when amending with visible light irradiation in the Fe3O4/C/Cu-H2O2 system, and MB (100 mg L-1) was nearly removed within 60 min. The Fe3O4/C/Cu composite showed good recyclability and could be conveniently separated by an applied magnetic field. Compared with conventional methods for mesoporous composite construction, the thermolysis method using mixed metal tartrates as precursors has the advantages of easy preparation and low cost. This strategy provides a facile, cheap and green method for the synthesis of mesoporous composites as excellent Fenton-like catalysts, without any additional reductants or organic surfactants.

  6. Hepatitis C virus and its protein NS4B activate the cancer-related STAT3 pathway via the endoplasmic reticulum overload response.

    PubMed

    Kong, Lingbao; Li, Shanshan; Yu, Xilan; Fang, Xiaonan; Xu, Ahui; Huang, Mingjie; Wu, Xiaoyu; Guo, Yunli; Guo, Fenglin; Xu, Jin

    2016-08-01

    Oxidative stress induces the activation of signal transducer and activator of transcription 3 (STAT3), which plays an important role in hepatocellular carcinoma (HCC). We have previously reported that hepatitis C virus (HCV) and its protein NS4B induce the production of reactive oxygen species (ROS) via the endoplasmic reticulum overload response (EOR) in human hepatocytes. Here, we found that NS4B and HCV induce STAT3 activation and stimulate the expression of cancer-related STAT3 target genes, including VEGF, c-myc, MMP-9 and Mcl-1, by EOR in human hepatocytes. Moreover, the cancer-related STAT3 pathway activated by NS4B and HCV via EOR were found to promote human hepatocyte viability. Taken together, these findings revealed that HCV NS4B might contribute to HCC by activating the EOR-mediated cancer-related STAT3 pathway, and this could provide novel insights into HCV-induced HCC.

  7. Targeting a novel cancer-driving protein (LAPTM4B-35) by a small molecule (ETS) to inhibit cancer growth and metastasis.

    PubMed

    Li, Maojin; Zhou, Rouli; Shan, Yi; Li, Li; Wang, Lin; Liu, Gang

    2016-09-06

    Our previous studies demonstrated that LAPTM4B-35 is overexpressed in a variety of solid cancers including hepatocellular carcinoma (HCC), and is an independent factor for prognosis. LAPTM4B-35 overexpression causes carcinogenesis and enhances cancer growth, metastasis and multidrug resistance, and thus may be a candidate for therapeutic targeting. The present study shows ethylglyoxal bisthiosemicarbazon (ETS) has effective anticancer activity through LAPTM4B-35 targeting. Bel-7402 and HepG2 cell lines from human HCC were used as cell models in which LAPTM4B-35 is highly expressed, and a human fetal liver cell line was used as a control. The results showed ETS has a specific and pronounced lethal effect on HCC cells, but not on fetal liver cells in culture. ETS also attenuated growth and metastasis of human HCC xenograft in nude mice, and extended the life span of mice with HCC. ETS induced HCC cell apoptosis, and upregulated a large number of proapoptotic genes and downregulated antiapoptotic genes. When endogenous overexpression of LAPTM4B-35 was knocked down with RNAi, the killing effect of ETS on HepG2 cells was significantly attenuated. ETS also inhibited phosphorylation of LAPTM4B-35 Tyr285, which involves in activation of the PI3K/Akt signaling pathway induced by LAPTM4B-35 overexpression. In addition, the induction of alterations in quantity of c-Myc, Bcl-2, Bax, cyclinD1 and Akt-p molecules in HepG2 cells by LAPTM4B-35 overexpression could be reversed by ETS.

  8. CASK interacts with PMCA4b and JAM-A on the mouse sperm flagellum to regulate Ca2+ homeostasis and motility.

    PubMed

    Aravindan, Rolands G; Fomin, Victor P; Naik, Ulhas P; Modelski, Mark J; Naik, Meghna U; Galileo, Deni S; Duncan, Randall L; Martin-Deleon, Patricia A

    2012-08-01

    Deletion of the highly conserved gene for the major Ca(2+) efflux pump, Plasma membrane calcium/calmodulin-dependent ATPase 4b (Pmca4b), in the mouse leads to loss of progressive and hyperactivated sperm motility and infertility. Here we first demonstrate that compared to wild-type (WT), Junctional adhesion molecule-A (Jam-A) null sperm, previously shown to have motility defects and an abnormal mitochondrial phenotype reminiscent of that seen in Pmca4b nulls, exhibit reduced (P < 0.001) ATP levels, significantly (P < 0.001) greater cytosolic Ca(2+) concentration ([Ca(2+) ](c)) and ∼10-fold higher mitochondrial sequestration, indicating Ca(2+) overload. Investigating the mechanism involved, we used co-immunoprecipitation studies to show that CASK (Ca(2+) /calmodulin-dependent serine kinase), identified for the first time on the sperm flagellum where it co-localizes with both PMCA4b and JAM-A on the proximal principal piece, acts as a common interacting partner of both. Importantly, CASK binds alternatively and non-synergistically with each of these molecules via its single PDZ (PDS-95/Dlg/ZO-1) domain to either inhibit or promote efflux. In the absence of CASK-JAM-A interaction in Jam-A null sperm, CASK-PMCA4b interaction is increased, resulting in inhibition of PMCA4b's enzymatic activity, consequent Ca(2+) accumulation, and a ∼6-fold over-expression of constitutively ATP-utilizing CASK, compared to WT. Thus, CASK negatively regulates PMCA4b by directly binding to it and JAM-A positively regulates it indirectly through CASK. The decreased motility is likely due to the collateral net deficit in ATP observed in nulls. Our data indicate that Ca(2+) homeostasis in sperm is maintained by the relative ratios of CASK-PMCA4b and CASK-JAM-A interactions.

  9. Local Circuits of V1 Layer 4B Neurons Projecting to V2 Thick Stripes Define Distinct Cell Classes and Avoid Cytochrome Oxidase Blobs.

    PubMed

    Yarch, Jeff; Federer, Frederick; Angelucci, Alessandra

    2017-01-11

    Decades of anatomical studies on the primate primary visual cortex (V1) have led to a detailed diagram of V1 intrinsic circuitry, but this diagram lacks information about the output targets of V1 cells. Understanding how V1 local processing relates to downstream processing requires identification of neuronal populations defined by their output targets. In primates, V1 layers (L)2/3 and 4B send segregated projections to distinct cytochrome oxidase (CO) stripes in area V2: neurons in CO blob columns project to thin stripes while neurons outside blob columns project to thick and pale stripes, suggesting functional specialization of V1-to-V2 CO streams. However, the conventional diagram of V1 shows all L4B neurons, regardless of their soma location in blob or interblob columns, as projecting selectively to CO blobs in L2/3, suggesting convergence of blob/interblob information in L2/3 blobs and, possibly, some V2 stripes. However, it is unclear whether all L4B projection neurons show similar local circuitries. Using viral-mediated circuit tracing, we have identified the local circuits of L4B neurons projecting to V2 thick stripes in macaque. Consistent with previous studies, we found the somata of this L4B subpopulation to reside predominantly outside blob columns; however, unlike previous descriptions of local L4B circuits, these cells consistently projected outside CO blob columns in all layers. Thus, the local circuits of these L4B output neurons, just like their extrinsic projections to V2, preserve CO streams. Moreover, the intra-V1 laminar patterns of axonal projections identify two distinct neuron classes within this L4B subpopulation, including a rare novel neuron type, suggestive of two functionally specialized output channels.

  10. The D4A Digitiser

    NASA Astrophysics Data System (ADS)

    de Cuyper, J.-P.; Winter, L.

    2006-07-01

    The D4A (Digital Access to Aerial- and Astro-photographic Archives) project aims to acquire the necessary know-how, hardware and software to digitise the astro-photographic collections of the Royal Observatory of Belgium (ROB) and the aerial-photographic collections of the National Geographic Institute and the Royal Museum of Central Africa in collaboration with AGFA-Gevaert, a world-leader in photographic matters. The final design of the ``D4A Digitiser'' that is being built by the ROB in Brussels is presented. A geometric benchmark testing of different commercial flatbed scanners is given and the results are compared with the requirements needed for the astrometric and photometric data extraction from the digitised images.

  11. LAPTM4B is a PtdIns(4,5)P2 effector that regulates EGFR signaling, lysosomal sorting, and degradation.

    PubMed

    Tan, Xiaojun; Sun, Yue; Thapa, Narendra; Liao, Yihan; Hedman, Andrew C; Anderson, Richard A

    2015-02-12

    Lysosomal degradation is essential for the termination of EGF-stimulated EGF receptor (EGFR) signaling. This requires EGFR sorting to the intraluminal vesicles (ILVs) of multi-vesicular endosomes (MVEs). Cytosolic proteins including the ESCRT machineries are key regulators of EGFR intraluminal sorting, but roles for endosomal transmembrane proteins in receptor sorting are poorly defined. Here, we show that LAPTM4B, an endosomal transmembrane oncoprotein, inhibits EGF-induced EGFR intraluminal sorting and lysosomal degradation, leading to enhanced and prolonged EGFR signaling. LAPTM4B blocks EGFR sorting by promoting ubiquitination of Hrs (an ESCRT-0 subunit), which inhibits the Hrs association with ubiquitinated EGFR. This is counteracted by the endosomal PIP kinase, PIPKIγi5, which directly binds LAPTM4B and neutralizes the inhibitory function of LAPTM4B in EGFR sorting by generating PtdIns(4,5)P2 and recruiting SNX5. PtdIns(4,5)P2 and SNX5 function together to protect Hrs from ubiquitination, thereby promoting EGFR intraluminal sorting. These results reveal an essential layer of EGFR trafficking regulated by LAPTM4B, PtdIns(4,5)P2 signaling, and the ESCRT complex and define a mechanism by which the oncoprotein LAPTM4B can transform cells and promote tumor progression.

  12. Histone deacetylase inhibitor- and PMA-induced upregulation of PMCA4b enhances Ca2+ clearance from MCF-7 breast cancer cells.

    PubMed

    Varga, Karolina; Pászty, Katalin; Padányi, Rita; Hegedűs, Luca; Brouland, Jean-Philippe; Papp, Béla; Enyedi, Agnes

    2014-02-01

    The expression of the plasma membrane Ca2+ ATPase (PMCA) isoforms is altered in several types of cancer cells suggesting that they are involved in cancer progression. In this study we induced differentiation of MCF-7 breast cancer cells by histone deacetylase inhibitors (HDACis) such as short chain fatty acids (SCFAs) or suberoylanilide hydroxamic acid (SAHA), and by phorbol 12-myristate 13-acetate (PMA) and found strong upregulation of PMCA4b protein expression in response to these treatments. Furthermore, combination of HDACis with PMA augmented cell differentiation and further enhanced PMCA4b expression both at mRNA and protein levels. Immunocytochemical analysis revealed that the upregulated protein was located mostly in the plasma membrane. To examine the functional consequences of elevated PMCA4b expression, the characteristics of intracellular Ca2+ signals were investigated before and after differentiation inducing treatments, and also in cells overexpressing PMCA4b. The increased PMCA4b expression - either by treatment or overexpression - led to enhanced Ca2+ clearance from the stimulated cells. We found pronounced PMCA4 protein expression in normal breast tissue samples highlighting the importance of this pump for the maintenance of mammary epithelial Ca2+ homeostasis. These results suggest that modulation of Ca2+ signaling by enhanced PMCA4b expression may contribute to normal development of breast epithelium and may be lost in cancer.

  13. PTC725, an NS4B-Targeting Compound, Inhibits a Hepatitis C Virus Genotype 3 Replicon, as Predicted by Genome Sequence Analysis and Determined Experimentally

    PubMed Central

    Graci, Jason D.; Jung, Stephen P.; Pichardo, John; Tong, Xiao; Gu, Zhengxian

    2016-01-01

    PTC725 is a small molecule NS4B-targeting inhibitor of hepatitis C virus (HCV) genotype (gt) 1 RNA replication that lacks activity against HCV gt2. We analyzed the Los Alamos HCV sequence database to predict susceptible/resistant HCV gt's according to the prevalence of known resistance-conferring amino acids in the NS4B protein. Our analysis predicted that HCV gt3 would be highly susceptible to the activity of PTC725. Indeed, PTC725 was shown to be active against a gt3 subgenomic replicon with a 50% effective concentration of ∼5 nM. De novo resistance selection identified mutations encoding amino acid substitutions mapping to the first predicted transmembrane region of NS4B, a finding consistent with results for PTC725 and other NS4B-targeting compounds against HCV gt1. This is the first report of the activity of an NS4B targeting compound against HCV gt3. In addition, we have identified previously unreported amino acid substitutions selected by PTC725 treatment which further demonstrate that these compounds target the NS4B first transmembrane region. PMID:27620477

  14. Theoretical computation of thermophysical properties of high-temperature F2, CF4, C2F2, C2F4, C2F6, C3F6 and C3F8 plasmas

    NASA Astrophysics Data System (ADS)

    Wang, WeiZong; Wu, Yi; Rong, MingZhe; Éhn, László; Černušák, Ivan

    2012-07-01

    The calculated values of thermodynamic and transport properties of pure F2 and fluorocarbon compounds CF4, C2F2, C2F4, C2F6, C3F6 and C3F8 at high temperatures are presented in this paper. The thermodynamic properties are determined by the method of Gibbs free energy minimization, using standard thermodynamic tables. The transport properties, including electron diffusion coefficients, viscosity, thermal conductivity and electrical conductivity, are evaluated using the Chapman-Enskog method expanded up to the third-order approximation (second order for viscosity). The most accurate cross-section data that could be located are used to evaluate collision integrals. The calculations based on the assumption of local thermodynamic equilibrium are performed for atmospheric-pressure plasmas in the temperature range from 300 to 30 000 K for different pressures between 0.1 and 10 atm. The results of F2, CF4, C2F2, C2F4 and C2F6 are compared with those of previously published studies. Larger discrepancies occur for transport coefficients; these are explained in terms of the different values of the collision integrals that were used. The results presented here are expected to be more accurate because of the improved collision integrals employed.

  15. Kinetic analysis of the calmodulin-binding region of the plasma membrane calcium pump isoform 4b.

    PubMed

    Penheiter, Alan R; Filoteo, Adelaida G; Penniston, John T; Caride, Ariel J

    2005-02-15

    The sequence L(1086)RRGQILWFRGLNRIQTQIKVVKAFHSS(1113) (peptide C28) is responsible for calmodulin binding to PMCA4b. In this work, peptides following the above sequence were progressively shortened either at the N-terminus (C28NDelta3, C28NDelta5, or C28NDelta6) or at the C-terminus (C20, C22, C23, and C25). Competitive inhibition of PMCA activity was used to measure apparent dissociation constants of the complexes between calmodulin and C28 or progressively shortened peptides. Additionally, equilibrium titrations were used to measure the apparent dissociation constants of the various peptides with TA-calmodulin by changes in TA-calmodulin fluorescence and Trp fluorescence of the peptides. At the N-terminus, deletion of five residues did not change calmodulin affinity, but deletion of six residues resulted in a 5-fold decrease in affinity. There were no major differences in the time course of TA-CaM binding, but C28NDelta6 exhibited a different time course of Trp fluorescence change. At the C-terminus, deletion of five residues (C23) or more resulted in a net increase in fluorescence of TA-CaM upon binding, while longer peptides (C25 and C28) produced both a transient increase and a net decrease in the fluorescence of TA-CaM. Global regression analysis revealed that binding of TA-CaM to the C23 peptide could be fit by a two-step model, while longer peptides required three-step models for adequate fitting. TA-calmodulin dissociated rapidly from C23, C22, and C20, resulting in a marked increase in apparent K(d). Thus, the sequence I(1091)LWFRGLNRIQTQIKVVKAF(1110) (C25NDelta5) is required to reproduce the calmodulin-binding properties of C28. When F(1110) was replaced by A, the TA-calmodulin association and dissociation kinetics resembled C23 kinetics, but changing V(1107) to A produced a smaller effect, suggesting that F(1110), rather than V(1107), is the main anchor for the N-terminal lobe of calmodulin in PMCA4b.

  16. C/EBPβ-LAP*/LAP Expression Is Mediated by RSK/eIF4B-Dependent Signalling and Boosted by Increased Protein Stability in Models of Monocytic Differentiation

    PubMed Central

    Christmann, Martin; Friesenhagen, Judith; Westphal, Andreas; Pietsch, Daniel; Brand, Korbinian

    2015-01-01

    The transcription factor C/EBPβ plays a key role in monocytic differentiation and inflammation. Its small isoform LIP is associated with proliferation at early premonocytic developmental stages and regulated via mTOR-dependent signalling. During later stages of (pre)monocytic differentiation there is a considerable increase in the large C/EBPβ isoforms LAP*/LAP which inhibit proliferation thus supporting terminal differentiation. Here, we showed in different models of monocytic differentiation that this dramatic increase in the LAP*/LAP protein and LAP/LIP ratio was accompanied by an only modest/retarded mRNA increase suggesting an important role for (post)translational mechanisms. We found that LAP*/LAP formation was induced via MEK/RSK-dependent cascades, whereas mTOR/S6K1 were not involved. Remarkably, LAP*/LAP expression was dependent on phosphorylated eIF4B, an acceleratory protein of RNA helicase eIF4A. PKR inhibition reduced the expression of eIF4B and C/EBPβ in an eIF2α-independent manner. Furthermore, under our conditions a marked stabilisation of LAP*/LAP protein occurred, accompanied by reduced chymotrypsin-like proteasome/calpain activities and increased calpastatin levels. Our study elucidates new signalling pathways inducing LAP*/LAP expression and indicates new alternative PKR functions in monocytes. The switch from mTOR- to RSK-mediated signalling to orchestrate eIF4B-dependent LAP*/LAP translation, accompanied by increased protein stability but only small mRNA changes, may be a prototypical example for the regulation of protein expression during selected processes of differentiation/proliferation. PMID:26646662

  17. Ferulic acid prevents LPS-induced up-regulation of PDE4B and stimulates the cAMP/CREB signaling pathway in PC12 cells

    PubMed Central

    Huang, Hao; Hong, Qian; Tan, Hong-ling; Xiao, Cheng-rong; Gao, Yue

    2016-01-01

    Aim: Phosphodiesterase 4 (PDE4) isozymes are involved in different functions, depending on their patterns of distribution in the brain. The PDE4 subtypes are distributed in different inflammatory cells, and appear to be important regulators of inflammatory processes. In this study we examined the effects of ferulic acid (FA), a plant component with strong anti-oxidant and anti-inflammatory activities, on lipopolysaccharide (LPS)-induced up-regulation of phosphodiesterase 4B (PDE4B) in PC12 cells, which in turn regulated cellular cAMP levels and the cAMP/cAMP response element binding protein (CREB) pathway in the cells. Methods: PC12 cells were treated with LPS (1 μg/mL) for 8 h, and the changes of F-actin were detected using laser scanning confocal microscopy. The levels of pro-inflammatory cytokines were measured suing ELISA kits, and PDE4B-specific enzymatic activity was assessed with a PDE4B assay kit. The mRNA levels of PDE4B were analyzed with Q-PCR, and the protein levels of CREB and phosphorylated CREB (pCREB) were determined using immunoblotting. Furthermore, molecular docking was used to identify the interaction between PDE4B2 and FA. Results: Treatment of PC12 cells with LPS induced thick bundles of actin filaments appearing in the F-actin cytoskeleton, which were ameliorated by pretreatment with FA (10–40 μmol/L) or with a PDE4B inhibitor rolipram (30 μmol/L). Pretreatment with FA dose-dependently inhibited the LPS-induced production of TNF-α and IL-1β in PC12 cells. Furthermore, pretreatment with FA dose-dependently attenuated the LPS-induced up-regulation of PDE4 activity in PC12 cells. Moreover, pretreatment with FA decreased LPS-induced up-regulation of the PDE4B mRNA, and reversed LPS-induced down-regulation of CREB and pCREB in PC12 cells. The molecular docking results revealed electrostatic and hydrophobic interactions between FA and PDE4B2. Conclusion: The beneficial effects of FA in PC12 cells might be conferred through inhibition of LPS

  18. Two-step infiltration of aluminum melts into Al-Ti-B4C-CuO powder mixture pellets

    NASA Astrophysics Data System (ADS)

    Zhang, Jingjing; Lee, Jung-Moo; Cho, Young-Hee; Kim, Su-Hyeon; Yu, Huashun

    2016-03-01

    Aluminum matrix composites with a high volume fraction of B4C and TiB2 were fabricated by a novel processing technique - a quick spontaneous infiltration process. The process combines a pressureless infiltration with the combustion reaction of Al-Ti-B4C-CuO in molten aluminum. The process is realized in a simple and economical way in which the whole process is performed in air in a few minutes. To verify the rapidity of the process, the infiltration kinetics was calculated based on the Washburn equation in which melt flows into a porous skeleton. However, there was a noticeable deviation from the calculated results with the experimental results. Considering the cross-sections of the samples at different processing times, a new infiltration model (two step infiltration) consisting of macro-infiltration and micro-infiltration is suggested. The calculated kinetics results in light of the proposed model agree well with the experimental results.

  19. Time-dependent radio fine structure of the compact sources NRAO 150 and 4C 39.25

    NASA Technical Reports Server (NTRS)

    Baath, L. B.; Cotton, W. D.; Counselman, C. C.; Shapiro, I. I.; Wittels, J. J.; Hinteregger, H. F.; Knight, C. A.; Rogers, A. E. E.; Whitney, A. R.; Clark, T. A.

    1980-01-01

    Very long baseline interferometer observations at 7.85 GHz have been used to probe the milliarcsecond structure of the unidentified, very compact radio source NRAO 150 and QSO 4 C 39.25. NRAO 150 exhibited no structural variations from 1972 to the end of 1974. A model with two circular Gaussian components fits the data well. NRAO 150 had a flux density of 7.6 plus or minus 0.5 Jy in the compact component; 4 C 39.25 showed a two-component structure, the components having a separation of (2.02 plus or minus 0.05 arc sec) x 10 to the -3rd power. The upper bound on the speed of transverse separation is 0.0001 arc sec per year or less than 2.7 c. From the spectrum there are also indications of a third, larger component.

  20. Synthesis and characterization of LiFePO4/C cathode materials by sol-gel method.

    PubMed

    Liu, Shuxin; Yin, Hengbo; Wang, Haibin; Wang, Hong

    2014-09-01

    The carbon coated LiFePO4 cathode materials (LiFePO4/C) were successfully synthesized by sol-gel method with glucose, citric acid and PEG-4000 as dispersant and carbon source, respectively. The microstructure and grain size of LiFePO4/C composite were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy. The results showed that the carbon source and calcination temperature had important effect on the graphitization degree of carbon; the carbon decomposed by citric acid had higher graphitization degree; with calcination temperature rising, the graphitization degree of carbon increased and the particles size increased. The graphitization degree and grain size were very important for improving the electrochemical performance of LiFePO4 cathode materials, according to the experimental results, the sample LFP-700 (LFP-C) which was synthesized with citric acid as dispersant at 700 degree C had lower polarization and larger discharge capacity.

  1. Formation mechanism of LiFePO 4/C composite powders investigated by X-ray absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Hsu, Kuei-Feng; Hu, Shao-Kang; Chen, Chinh-Hsiang; Cheng, Ming-Yao; Tsay, Sun-Yuan; Chou, Tse-Chuan; Sheu, Hwo-Shuenn; Lee, Jyh-Fu; Hwang, Bing-Joe

    The local structure and oxidation states for both the precursors and the LiFePO 4/C composite powders were investigated by X-ray absorption spectroscopy (XAS) to provide a deep insight into their formation mechanism. It was found that the local structure and oxidation states of the precursors and the synthesized LiFePO 4/C powders as well as the electrochemical properties of the synthesized powders were strongly influenced by the R ratio (R: molar ratio of citric acid to total metal ions). The oxidation states of iron ions of the precursors for R = 1 and 0.75 consist mainly of Fe(II) and traces of Fe(III). However, the oxidation state of iron ions of the precursor for R = 0.5 comprises mainly of Fe(III). The oxidation state of iron ions of all the synthesized powders is Fe(II). The structure of the precursors and the synthesized powders for R = 1 and 0.75 is more ordering than that for R = 0.5. It is in good agreement with the observation of the cation mixing obtained from the Riteveld analysis of the XRD data. The better the electrochemical performance is, the more ordering the structure or the less the cation mixing. However, the effect of the R values on the carbon content is also essential for the electrochemical properties of the synthesized LiFePO 4/C composite powders. Increasing the carbon content leads to the increase in the electronic conductivity but impedes the Li + ion diffusion of the composite materials. Consequently, the powders synthesized at the optimal R ratio of 0.75 exhibited the highest initial capacity, about 150 mAh g -1 when cycled at 1/40 C rate at room temperature. The structural scheme of the precursors and the synthesized powders and the formation mechanism of the LiFePO 4/C composite powders are also addressed in this work.

  2. Synthesis and properties of novel 2'-C,4'-C-ethyleneoxy-bridged 2'-deoxyribonucleic acids with exocyclic methylene groups.

    PubMed

    Osawa, Takashi; Obika, Satoshi; Hari, Yoshiyuki

    2016-10-12

    Three 2'-C,4'-C-ethyleneoxy-bridged 2'-deoxyribonucleic acids possessing six-membered bridges with 6'-oxygen and 8'-exocyclic methylene groups (methylene-EoDNAs) were designed and synthesized in nine to ten steps from 5-methyluridine. The methylene-EoDNA-modified oligonucleotides showed excellent binding affinity with target ssRNA and extremely high nuclease resistance compared with natural oligonucleotides. These results proved the potential of methylene-EoDNAs for nucleic acid based technology.

  3. First-principles study of configurational disorder in B4C using a superatom-special quasirandom structure method

    NASA Astrophysics Data System (ADS)

    Ektarawong, A.; Simak, S. I.; Hultman, L.; Birch, J.; Alling, B.

    2014-07-01

    Configurationally disordered crystalline boron carbide, with the composition B4C, is studied using first-principles calculations. We investigate both dilute and high concentrations of carbon-boron substitutional defects. For the latter purpose, we suggest a superatom's picture of the complex structure and combine it with a special quasirandom structure approach for disorder. In this way, we model a random distribution of high concentrations of the identified low-energy defects: (1) bipolar defects and (2) rotation of icosahedral carbon among the three polar-up sites. Additionally, the substitutional disorder of the icosahedral carbon at all six polar sites, as previously discussed in the literature, is also considered. Two configurational phase transitions from the ordered to the disordered configurations are predicted to take place upon an increase in temperature using a mean-field approximation for the entropy. The first transition, at 870 K, induces substitutional disorder of the icosahedral carbon atoms among the three polar-up sites; meanwhile the second transition, at 2325 K, reveals the random substitution of the icosahedral carbon atoms at all six polar sites coexisting with bipolar defects. Already the first transition removes the monoclinic distortion existing in the ordered ground-state configuration and restore the rhombohedral system (R3m). The restoration of inversion symmetry yielding the full rhombohedral symmetry (R3¯m ) on average, corresponding to what is reported in the literature, is achieved after the second transition. Investigating the effects of high pressure on the configurational stability of the disordered B4C phases reveals a tendency to stabilize the ordered ground-state configuration as the configurationally ordering/disordering transition temperature increases with pressure exerted on B4C. The electronic density of states, obtained from the disordered phases, indicates a sensitivity of the band gap to the degree of configurational

  4. Effects of Nb-doped on the structure and electrochemical performance of LiFePO{sub 4}/C composites

    SciTech Connect

    Ma, Zhipeng; Shao, Guangjie; Wang, Guiling; Zhang, Ying; Du, Jianping

    2014-02-15

    The olivine-type niobium doping Li{sub 1−x}Nb{sub x}FePO{sub 4}/C (x=0, 0.005, 0.010, 0.015, 0.025) cathode materials were synthesized via a two-step ball milling solid state reaction. The effects of Nb doping were charactered by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), galvanostatic intermittent titration technique (GITT), cyclic voltammetry (CV), electrochemical impedance spectra (EIS) and galvanostatic charge–discharge. It is found that Nb doping enlarges the interplanar distance of crystal plane parallel to [0 1 0] direction in LiFePO{sub 4}. In other words, it widens the one dimensional diffusion channels of Li{sup +} along the [0 1 0] direction. Electrochemical test results indicate that the Li{sub 0.99}Nb{sub 0.01}FePO{sub 4}/C composite exhibits the best electrochemical performance with initial special discharge capacity of 139.3 mA h g{sup −1} at 1 C rate. The present synthesis route is promising in making the solid state reaction method more practical for preparation of the LiFePO{sub 4} material. - Graphical abstract: The proper amount of Nb doping widens the one dimensional diffusion channels of Li{sup +} along the [0 1 0] direction. Display Omitted - Highlights: • The Nb doping LiFePO{sub 4}/C is prepared by a facile two-step ball milling solid state reaction. • The sample possesses the better high-rate performance. • The tap density of Li{sub 0.99}Nb{sub 0.01}FePO{sub 4}/C sample is 1.76 g cm{sup −3}.

  5. Boron uptake in tumors, cerebrum and blood from [10B]NA4B24H22S2

    DOEpatents

    Slatkin, Daniel N.; Micca, Peggy L.; Fairchild, Ralph G.

    1988-01-01

    A stable boronated (.sup.10 B-labeled) compound, sodium mercaptoundecahydrododecaborate is infused in the form of the disulfide dimer, [.sup.10 B]Na.sub.4 B.sub.24 H.sub.22 S.sub.2, at a dose of about 200 .mu.g .sup.10 B per gm body weight. The infusion is performed into the blood or peritoneal cavity of the patient slowly over a period of many days, perhaps one week or more, at the rate of roughly 1 .mu.g .sup.10 B per gm body weight per hour. Use of this particular boronated dimer in the manner or similarly to the manner so described permits radiotherapeutically effective amounts of boron to accumulate in tumors to be treated by boron neutron capture radiation therapy and also permits sufficient retention of boron in tumor after the cessation of the slow infusion, so as to allow the blood concentration of .sup.10 B to drop or to be reduced artificially to a radiotherapeutically effective level, less than one-half of the concentration of .sup.10 B in the tumor.

  6. Boron uptake in tumors, cerebrum and blood from [10B]NA4B24H22S2

    DOEpatents

    Slatkin, Daniel N.; Micca, Peggy L.; Fairchild, Ralph G.

    1988-08-02

    A stable boronated (.sup.10 B-labeled) compound, sodium mercaptoundecahydrododecaborate is infused in the form of the disulfide dimer, [.sup.10 B]Na.sub.4 B.sub.24 H.sub.22 S.sub.2, at a dose of about 200 .mu.g .sup.10 B per gm body weight. The infusion is performed into the blood or peritoneal cavity of the patient slowly over a period of many days, perhaps one week or more, at the rate of roughly 1 .mu.g .sup.10 B per gm body weight per hour. Use of this particular boronated dimer in the manner or similarly to the manner so described permits radiotherapeutically effective amounts of boron to accumulate in tumors to be treated by boron neutron capture radiation therapy and also permits sufficient retention of boron in tumor after the cessation of the slow infusion, so as to allow the blood concentration of .sup.10 B to drop or to be reduced artificially to a radiotherapeutically effective level, less than one-half of the concentration of .sup.10 B in the tumor.

  7. Analysis of C3b/C4b receptor (CR1) polymorphic variants by tryptic peptide mapping.

    PubMed

    Nickells, M W; Seya, T; Holers, V M; Atkinson, J P

    1986-06-01

    The human C3b/C4b receptor (CR1) binds the major activation and opsonic fragments of the third (C3) and fourth (C4) components of complement. CR1 is a single chain integral membrane glycoprotein widely distributed on peripheral blood cells. Four codominantly inherited allelic variants with Mrs of 160,000, 190,000, 220,000 and 250,000 have been described. To address the structural basis for this unusual polymorphism, CR1 from donors expressing three of the four allelic variants was purified from surface labeled (125I) erythrocytes by iC3-Sepharose affinity chromatography and the variants compared by tryptic peptide mapping (TPM). The TPMs of each variant contained the same major peaks and minor peak areas and were nearly identical to one another. Tryptic peptide mappings of the 190,000 Mr erythrocyte CR1, which was purified prior to iodination, were similar to those derived from surface iodinated CR1. The TPMs of erythrocyte and granulocyte CR1 from the same donor differed by a single peak of increased prominence in the granulocyte map. These results indicate a conservation in amino acid sequence for those peptides detected. In view of these data and those of other studies of the structure and genetics of CR1 and related proteins, it is suggested in this paper that the allelic variation relates to CR1, being composed of repeating amino acid sequences.

  8. Modulation of C4b-binding protein isoforms during the acute phase response caused by orthopedic surgery.

    PubMed

    Criado-García, O; González-Rubio, C; López-Trascasa, M; Pascual-Salcedo, D; Munuera, L; Rodríguez de Córdoba, S

    1997-01-01

    Orthopedic surgery is described as an event with a high risk of thromboembolic diseases. This is probably a consequence of a synergistic combination of different risk factors in the patients subjected to this type of surgery, including age, immobilization, anesthesia and different hypercoagulable states. After surgery patients develop an acute-phase response that leads to changes in several plasma proteins. One of these proteins is the complement regulator C4b-binding protein (C4BP). We have recently shown that in some acute-phase patients C4BP is incorrectly controlled (with elevation of the C4BP beta-containing isoforms), leading to a potential hypercoagulable state by decreasing the plasma levels of free (active) protein S. Here we have studied whether patients subjected to orthopedic surgery have an appropriate modulation of the C4BP isoforms during their postoperative acute-phase responses. We have analyzed the evolution of the C4BP isoforms in serial samples from 11 patients who have undergone knee (or hip) prosthesis surgery (mean age 70 years), or scoliosis surgery (mean age 18 years). Our data suggest a similar evolution of C4BP isoforms in all these patients, with an almost exclusive increase of C4BP isoforms lacking C4BP beta polypeptides and steady levels of free protein S.

  9. Heterodyne coherent detection of WDM PDM-QPSK signals with spectral efficiency of 4b/s/Hz.

    PubMed

    Li, Xinying; Dong, Ze; Yu, Jianjun; Yu, Jianguo; Chi, Nan

    2013-04-08

    We experimentally demonstrate heterodyne coherent detection of 8 × 112-Gb/s ultra-density wavelength-division-multiplexing (WDM) polarization-division-multiplexing quadrature-phase-shift-keying (PDM-QPSK) signal after 1120-km single-mode fiber-28 (SMF-28) transmission. The spectral efficiency (SE) is 4b/s/Hz. It is the first time to realize WDM signal transmission with high SE by adopting heterodyne coherent detection. At the heterodyne coherent receiver, intermediate frequency (IF) down conversion is realized in digital frequency domain after analog-to-digital conversion. A digital post filter and 1-bit maximum likelihood sequence estimation (MLSE) adopted after carrier phase estimation (CPE) in the conventional digital-signal-processing (DSP) process is used to suppress the enhanced noise and crosstalk as well as overcome the filtering effects. The bit-error ratio (BER) for all channels is under the forward-error-correction (FEC) limit of 3.8 × 10(-3) after 1120-km SMF-28 transmission.

  10. Heterodyne detection and transmission of 60-Gbaud PDM-QPSK signal with SE of 4b/s/Hz.

    PubMed

    Li, Xinying; Xiao, Jiangnan; Yu, Jianjun

    2014-04-21

    We experimentally demonstrate 8 × 240-Gb/s super-Nyquist wavelength-division-multiplexing (WDM) polarization-division-multiplexing quadrature-phase-shift-keying (PDM-QPSK) signal transmission on a 50-GHz grid with a net spectral efficiency (SE) of 4b/s/Hz adopting hardware-efficient simplified heterodyne detection. 9-ary quadrature-amplitude-modulation-like (9QAM-like) processing based on multi-modulus blind equalization (MMBE) is adopted to reduce analog-to-digital converter (ADC) bandwidth requirement and improve receiver sensitivity. The transmission distance at the soft-decision forward-error-correction (SD-FEC) threshold of 2 × 10(-2) is 2 × 420 km based on digital post filtering while largely extended to over 5 × 420 km based on 9QAM-like processing, which well illustrates 9QAM-like processing is more efficient for heterodyne coherent WDM system. Moreover, only two ADC channels are needed for simplified heterodyne detection of one 60-Gbaud PDM-QPSK WDM channel, and thus only one commercial oscilloscope (OSC) with two input ports can work well for each WDM channel.

  11. Electron transport behaviour and soft magnetic properties of bulk amorphous Fe72Si4B20Nb4 alloy

    NASA Astrophysics Data System (ADS)

    Panda, A. K.; Ghosh Chowdhury, S.; Mitra, A.; Nishiyama, N.; Inoue, A.

    2006-08-01

    The crystallization behaviour, electrical resistivity, magnetic and mechanical properties of as-quenched bulk amorphous Fe72Si4B20Nb4 alloy was investigated. The alloy, prepared in the form of rods by a copper mould casting technique, revealed an amorphous structure as observed from x-ray diffractometry. Differential scanning calorimetry and thermal variation of electrical resistivity measurements showed distinct glass transition temperature, Tg occurring 50-60 K below the crystallization onset (TX). Such a wide supercooled range was also attributed to the highly reduced glass transition temperature, Trg which was in the range of 0.56-0.58 found to be prevalent in good glass forming alloys. The alloy also showed a non-linear decrease in stability time at different temperatures between Tg and TX. The bulk amorphous alloy exhibited a drastic decrease in electrical resistivity around the glass transition temperature which was attributed to high electron propagation due to enhanced stress relaxation as result of a decrease in viscosity. The material exhibited superior soft magnetic properties with a coercivity value of 212 mOe, which is fairly low with respect to reported bulk amorphous alloys. The amorphous alloy also showed saturation induction of 12 kG and a moderate Curie temperature of 595 K. The as-quenched bulk amorphous alloy exhibited a high mechanical hardness of 1250 HV (Vickers). The superior soft magnetic properties coupled with high mechanical hardness opens up the scope for bulk amorphous Fe-Si-B systems with Nb incorporation.

  12. Intermittent microwave heating synthesized high performance spherical LiFePO{sub 4}/C for Li-ion batteries

    SciTech Connect

    Zou, Hongli; Zhang, Guanghui; Shen, Pei Kang

    2010-02-15

    An intermittent microwave heating method was used to synthesize spherical LiFePO{sub 4}/C in the presence of glucose as reductive agent and carbon source without the use of the inert gas in the oven processes. The FePO{sub 4} was used as iron precursor to reduce the cost and three lithium salts of Li{sub 2}CO{sub 3}, LiOH and CH{sub 3}COOLi were chosen for comparison of the resulting materials. The materials can be alternatively heated by this method at a temperature controllable mode for crystallization and phase transformation and to provide relaxation time for protecting particles growth. The X-ray diffraction and scanning electron microscope measurements confirmed that the LiFePO{sub 4}/C is olivine structured with the average particle size of 50-100 nm. The spherical LiFePO{sub 4}/C as cathode material showed better electrochemical performance in terms of the specific capacity and the cycling stability, which might be attributed to the highly crystallized phase, small particle distribution and improved conductivity by carbon connection.

  13. Characterization of a phage-like pyocin from the plant growth-promoting rhizobacterium Pseudomonas fluorescens SF4c.

    PubMed

    Fischer, Sonia; Godino, Agustina; Quesada, José Miguel; Cordero, Paula; Jofré, Edgardo; Mori, Gladys; Espinosa-Urgel, Manuel

    2012-06-01

    R-type and F-type pyocins are high-molecular-mass bacteriocins produced by Pseudomonas aeruginosa that resemble bacteriophage tails. They contain no head structures and no DNA, and are used as defence systems. In this report, we show that Pseudomonas fluorescens SF4c, a strain isolated from the wheat rhizosphere, produces a high-molecular-mass bacteriocin which inhibits the growth of closely related bacteria. A mutant deficient in production of this antimicrobial compound was obtained by transposon mutagenesis. Sequence analysis revealed that the transposon had disrupted a gene that we have named ptm, since it is homologous to that encoding phage tape-measure protein in P. fluorescens Pf0-1, a gene belonging to a prophage similar to phage-like pyocin from P. aeruginosa PAO1. In addition, we have identified genes from the SF4c pyocin cluster that encode a lytic system and regulatory genes. We constructed a non-polar ptm mutant of P. fluorescens SF4c. Heterologous complementation of this mutation restored the production of bacteriocin. Real-time PCR was used to analyse the expression of pyocin under different stress conditions. Bacteriocin was upregulated by mitomycin C, UV light and hydrogen peroxide, and was downregulated by saline stress. This report constitutes, to our knowledge, the first genetic characterization of a phage tail-like bacteriocin in a rhizosphere Pseudomonas strain.

  14. Effect of Al content on impact resistance behavior of Al-Ti-B4C composite fabricated under air atmosphere.

    PubMed

    Zhao, Qian; Liang, Yunhong; Zhang, Zhihui; Li, Xiujuan; Ren, Luquan

    2016-12-01

    Reaction behavior, mechanical property and impact resistance of TiC-TiB2/Al composite reacted from Al-Ti-B4C system with various Al content via combination method of combustion synthesis and hot pressed sintering under air was investigated. Al content was the key point to the variation of mechanical property and impact resistance. Increasing Al content could increase the density, strength and toughness of the composite. Due to exorbitant ceramic content, 10wt.% and 20wt.% Al-Ti-B4C composites exhibited poor molding ability and machinability. Flexural strength, fracture toughness, compressive strength and impact toughness of 30-50wt.% Al-Ti-B4C composite were higher than those of Al matrix. The intergranular fracture dispersed and defused impact load and restricted crack extension, enhancing the impact resistance of the composite. The composite with 50wt.% Al content owned highest mechanical properties and impact resistance. The results were useful for the application of TiC-TiB2/Al composite in impact resistance field of ceramic reinforced Al matrix composite.

  15. Effect of carbon source on the morphology and electrochemical performances of LiFePO4/C nanocomposites.

    PubMed

    Liu, Shuxin; Wang, Haibin; Yin, Hengbo; Wang, Hong; He, Jichuan

    2014-03-01

    The carbon coated LiFePO4 (LiFePO4/C) nanocomposites materials were successfully synthesized by sol-gel method. The microstructure and morphology of LiFePO4/C nanocomposites were characterized by X-ray diffraction, Raman spectroscopy and scanning electron microscopy. The results showed that the carbon layers decomposed by different dispersant and carbon source had different graphitization degree, and the sugar could decompose to form more graphite-like structure carbon. The carbon source and heat-treatment temperature had some effect on the particle size and morphology, the sample LFP-S700 synthesized by adding sugar as carbon source at 700 degrees C had smaller particle size, uniform size distribution and spherical shape. The electrochemical behavior of LiFePO4/C nanocomposites was analyzed using galvanostatic measurements and cyclic voltammetry (CV). The results showed that the sample LFP-S700 had higher discharge specific capacities, higher apparent lithium ion diffusion coefficient and lower charge transfer resistance. The excellent electrochemical performance of sample LFP-S700 could be attributed to its high graphitization degree of carbon, smaller particle size and uniform size distribution.

  16. The D4A Digitiser

    NASA Astrophysics Data System (ADS)

    de Cuyper, J.; Winter, L.

    2005-12-01

    The D4A (Digital Access to Aerial- and Astro-photographic Archives) project aims to acquire the necessary know-how, hardware and software to digitise the astro-photographic collections of the Royal Observatory of Belgium and the aerial-photographic collections of the National Geographic Institute and the Royal Museum of Central Africa in collaboration with AGFA-Gevaert. The D4A digitiser under construction consists of a granite based Aerotech ABL 3600 open frame air bearing XY positioning system, with custom build hardware to mount glass plates, film sheets and film rolls. The optical subsystem consists of a C-Cam Technologies CMOS camera mounted to a Schneider telecentric Xenoplan lens and will be illuminated by a computer controlled LED. The maximum scanning area is 350mm × 350mm with a speed of 6 plates (240mm × 240mm) per hour. A first benchmark of a prototype ABL 3600 was done and the proposed illumination system tested as detailed below.

  17. Pepper pathogenesis-related protein 4c is a plasma membrane-localized cysteine protease inhibitor that is required for plant cell death and defense signaling.

    PubMed

    Kim, Nak Hyun; Hwang, Byung Kook

    2015-01-01

    Xanthomonas campestris pv. vesicatoria (Xcv) type III effector AvrBsT triggers programmed cell death (PCD) and activates the hypersensitive response (HR) in plants. Here, we isolated and identified the plasma membrane localized pathogenesis-related (PR) protein 4c gene (CaPR4c) from pepper (Capsicum annuum) leaves undergoing AvrBsT-triggered HR cell death. CaPR4c encodes a protein with a signal peptide and a Barwin domain. Recombinant CaPR4c protein expressed in Escherichia coli exhibited cysteine protease-inhibitor activity and ribonuclease (RNase) activity. Subcellular localization analyses revealed that CaPR4c localized to the plasma membrane in plant cells. CaPR4c expression was rapidly and specifically induced by avirulent Xcv (avrBsT) infection. Transient expression of CaPR4c caused HR cell death in pepper leaves, which was accompanied by enhanced accumulation of H2 O2 and significant induction of some defense-response genes. Deletion of the signal peptide from CaPR4c abolished the induction of HR cell death, indicating a requirement for plasma membrane localization of CaPR4c for HR cell death. CaPR4c silencing in pepper disrupted both basal and AvrBsT-triggered resistance responses, and enabled Xcv proliferation in infected leaves. H2 O2 accumulation, cell-death induction, and defense-response gene expression were distinctly reduced in CaPR4c-silenced pepper. CaPR4c overexpression in transgenic Arabidopsis plants conferred greater resistance against infection by Pseudomonas syringae pv. tomato and Hyaloperonospora arabidopsidis. These results collectively suggest that CaPR4c plays an important role in plant cell death and defense signaling.

  18. Synthesis and antimicrobial activities of some novel 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles and 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazines carrying thioalkyl and sulphonyl phenoxy moieties.

    PubMed

    Karabasanagouda, T; Adhikari, Airody Vasudeva; Shetty, N Suchetha

    2007-04-01

    Thirty one new 6-aryl-3-{(4-substituted phenoxy) methyl}-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles (6a-s) and 6-aryl-3-[(4-substituted phenoxy methyl]-7H-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazines (7a-l) have been synthesized from 4-thioalkyl phenols (1a-b) through a multi-step reaction sequence. Compounds 1a-b reacted with ethyl chloroacetate in presence of acetone and potassium carbonate to give ethyl [4-(thioalkyl) phenoxy] acetates (2a-b). Further, 2a was oxidized to [4-(methyl sulphonyl) phenoxy] acetate (2c) using hydrogen peroxide in acetic acid. Reactions of (2a-c) with hydrazine hydrate in alcoholic medium furnished 2-[4-thiosubstituted phenoxy] acetohydrazides (3a-b) and 2-[4-methyl sulphonyl phenoxy] acetohydrazide (3c) which on treatment with carbon disulphide and methanolic potassium hydroxide yielded corresponding potassium dithiocarbazates (4a-c). They were then converted to 4-amino-5-[(4-thioalkyl phenoxy) methyl]-4H-1,2,4-triazole-3-thiols (5a-b) and 4-amino-5-[(4-methyl sulphonyl phenoxy) methyl]-4H-1,2,4-triazole-3-thiol (5c) by refluxing them with aqueous hydrazine hydrate. The title compounds 6a-s were prepared by condensing 5a-c with various aromatic carboxylic acids in presence of phosphorus oxychloride. The intermediates 5a-c, on condensation with various substituted phenacyl bromides afforded a series of title compounds (7a-l). The structures of new compounds 2a-7l were established on the basis of their elemental analysis, IR, (1)H NMR, (13)C NMR and mass spectral data. All the title compounds were subjected to in vitro antibacterial testing against four pathogenic strains and antifungal screening against three fungi. Preliminary results indicate that some of them exhibited promising activities and they deserve more consideration as potential antimicrobials.

  19. EWS-Oct-4B, an alternative EWS-Oct-4 fusion gene, is a potent oncogene linked to human epithelial tumours

    PubMed Central

    Kim, S; Lim, B; Kim, J

    2010-01-01

    Background: Characterisation of EWS-Oct-4 translocation fusion product in bone and soft-tissue tumours revealed a chimeric gene resulting from an in-frame fusion between EWS (Ewing's sarcoma gene) exons 1–6 and Oct-4 exons 1–4. Recently, an alternative form of the fusion protein between the EWS and Oct-4 genes, named EWS-Oct-4B, was reported in two types of epithelial tumours, a hidradenoma of the skin and a mucoepidermoid carcinoma of the salivary glands. As the N-terminal and POU domains of the EWS-Oct-4 and EWS-Oct-4B proteins are not structurally identical, we decided to investigate the functional consequences of the EWS-Oct-4B fusion. Methods: In this report, we have characterised the EWS-Oct-4B fusion protein. To investigate how the EWS-Oct-4B protein contributes to tumourigenesis in human cancers, we analysed its DNA-binding activity, subcellular localisation, transcriptional activation behaviour, and oncogenic properties. Results: We found that this new chimeric gene encodes a nuclear protein that binds DNA with the same sequence specificity as the parental Oct-4 protein or the fusion EWS-Oct-4 protein. We show that the nuclear localisation signal of EWS-Oct-4B is dependent on the POU DNA-binding domain, and we identified a cluster of basic amino acids, 269RKRKR273, in the POU domain that specifically mediates the nuclear localisation of EWS-Oct-4B. Comparison of the properties of EWS-Oct-4B and EWS-Oct-4 indicated that EWS-Oct-4B is a less-potent transcriptional activator of a reporter construct carrying the Oct-4-binding sites. Deletion analysis of the functional domains of EWS-Oct-4B revealed that the EWS N-terminal domain (NTD)B, POU, and C-terminal domain (CTD) are necessary for its full transactivation potential. Despite its reduced activity as a transcriptional activator, EWS-Oct-4B regulated the expression of fgf-4 (fibroblast growth factor-4) and nanog, which are potent mitogens, as well as of Oct-4 downstream target genes, the promoters of

  20. Farnesylated and methylated KRAS4b: high yield production of protein suitable for biophysical studies of prenylated protein-lipid interactions

    PubMed Central

    Gillette, William K.; Esposito, Dominic; Abreu Blanco, Maria; Alexander, Patrick; Bindu, Lakshman; Bittner, Cammi; Chertov, Oleg; Frank, Peter H.; Grose, Carissa; Jones, Jane E.; Meng, Zhaojing; Perkins, Shelley; Van, Que; Ghirlando, Rodolfo; Fivash, Matthew; Nissley, Dwight V.; McCormick, Frank; Holderfield, Matthew; Stephen, Andrew G.

    2015-01-01

    Prenylated proteins play key roles in several human diseases including cancer, atherosclerosis and Alzheimer’s disease. KRAS4b, which is frequently mutated in pancreatic, colon and lung cancers, is processed by farnesylation, proteolytic cleavage and carboxymethylation at the C-terminus. Plasma membrane localization of KRAS4b requires this processing as does KRAS4b-dependent RAF kinase activation. Previous attempts to produce modified KRAS have relied on protein engineering approaches or in vitro farnesylation of bacterially expressed KRAS protein. The proteins produced by these methods do not accurately replicate the mature KRAS protein found in mammalian cells and the protein yield is typically low. We describe a protocol that yields 5–10 mg/L highly purified, farnesylated, and methylated KRAS4b from insect cells. Farnesylated and methylated KRAS4b is fully active in hydrolyzing GTP, binds RAF-RBD on lipid Nanodiscs and interacts with the known farnesyl-binding protein PDEδ. PMID:26522388

  1. KEY COMPARISON: EURAMET regional key comparison EURAMET.M.FF-K4.b: Volume intercomparison at 20 L

    NASA Astrophysics Data System (ADS)

    Batista, Elsa; Lau, Peter

    2009-01-01

    In the sequence of CIPM key comparisons concerning volume calibrations an interregional comparison CCM.FF-K4 was performed between December 2003 and March 2005 for volume standards of 20 L and 100 mL. The corresponding regional part of this comparison within Europe was performed in 2006 for a 100 mL Gay-Lussac Pycnometer—EUROMET.M.FF-K4 (EUROMET project number 692). It was decided during the EUROMET meeting in Istanbul 2007 to also perform the regional part of this key comparison at 20 L, as EURAMET.M.FF-K4.b (EURAMET project number 1008). This comparison was guided by IPQ (Portugal) with SP (Sweden) acting has the pilot laboratory having taken part in the interregional exercise. Fourteen countries decided to participate in this comparison. One of three 20 L pipettes, 710-04FyV used in the CCM.FF K4, was readjusted by CENAM (Mexico), which initiated this key comparison and produced the transfer standard. The main purpose of this project was to compare the experimental results and uncertainty calculations in calibrating this 20 L pipette and linking the intra-regional European results with the results obtained in the previous inter-regional CIPM key comparison. The results of all laboratories participating in EURAMET project 1008 are presented in this report as well as their equivalence with the reference value of the key comparison CCM.FF-K4. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  2. A Novel Interaction between Complement Inhibitor C4b-binding Protein and Plasminogen That Enhances Plasminogen Activation*

    PubMed Central

    Agarwal, Vaibhav; Talens, Simone; Grandits, Alexander M.; Blom, Anna M.

    2015-01-01

    The complement, coagulation, and fibrinolytic systems are crucial for the maintenance of tissue homeostasis. To date numerous interactions and cross-talks have been identified between these cascades. In line with this, here we propose a novel, hitherto unknown interaction between the complement inhibitor C4b-binding protein (C4BP) and plasminogen of the fibrinolytic pathway. Binding of C4BP to Streptococcus pneumoniae is a known virulence mechanism of this pathogen and it was increased in the presence of plasminogen. Interestingly, the acute phase variant of C4BP lacking the β-chain and protein S binds plasminogen much stronger than the main isoform containing the β-chain and protein S. Indeed, the complement control protein (CCP) 8 domain of C4BP, which would otherwise be sterically hindered by the β-chain, primarily mediates this interaction. Moreover, the lysine-binding sites in plasminogen kringle domains facilitate the C4BP-plasminogen interaction. Furthermore, C4BP readily forms complexes with plasminogen in fluid phase and such complexes are present in human serum and plasma. Importantly, whereas the presence of plasminogen did not affect the factor I cofactor activity of C4BP, the activation of plasminogen by urokinase-type plasminogen activator to active plasmin was significantly augmented in the presence of C4BP. Taken together, our data demonstrate a novel interaction between two proteins of the complement and fibrinolytic system. Most complexes might be formed during the acute phase of inflammation and have an effect on the homeostasis at the site of injury or acute inflammation. PMID:26067271

  3. Atomistic study on the site preference and lattice vibration of Gd3-xYxCo29T4B10 (T=Al and Ge)

    NASA Astrophysics Data System (ADS)

    Cheng, Hai-Xia; Wang, Xiao-Xu; Hu, Yao-Wen; Zhang, Guo-Hua; Shen, Jiang; Qian, Ping; Chen, Nan-Xian

    2015-04-01

    The effects of the Y substitution for Gd on the structural stability and the site preference of intermetallics Gd3-xYxCo29T4B10 (T=Al and Ge) are studied by using a series of interatomic pair potentials. The calculated results show Y can stabilize Gd3-xYxCo29T4B10 with the tetragonal structure, and Y substitute for Gd with a strong preference for the 2b sites. The calculated lattice parameters are in good agreement with the experimental data. Furthermore, the total and partial phonon densities of states are evaluated for the Gd3-xYxCo29T4B10 compounds with the tetragonal structure. A qualitative analysis is carried out with the relevant potentials for the vibrational modes, which makes it possible to predict some properties related to lattice vibration.

  4. Absence of p16INK4a and truncation of ARF tumor suppressors in chickens

    PubMed Central

    Kim, Soo-Hyun; Mitchell, Michael; Fujii, Hideta; Llanos, Susana; Peters, Gordon

    2003-01-01

    The INK4b-ARF-INK4a locus on human chromosome 9p21 (Human Genome Organization designation CDKN2B-CDKN2A), and the corresponding locus on mouse chromosome 4, encodes three distinct products: two members of the INK4 cyclin-dependent kinase inhibitor family and a completely unrelated protein, ARF, whose carboxyl-terminal half is specified by the second exon of INK4a but in an alternative reading frame. As INK4 proteins block the phosphorylation of the retinoblastoma gene product and ARF protects p53 from degradation, the locus plays a key role in tumor suppression and the control of cell proliferation. To gain further insights into the relative importance of INK4a and ARF in different settings, we have isolated and characterized the equivalent locus in chickens. Surprisingly, although we identified orthologues of INK4b and ARF, chickens do not encode an equivalent of INK4a. Moreover, the reading frame for chicken ARF does not extend into exon 2, because splicing occurs in a different register to that used in mammals. The resultant 60-aa product nevertheless shares functional attributes with its mammalian counterparts. As well as indicating that the locus has been subject to dynamic evolutionary pressures, these unexpected findings suggest that in chickens, the tumor-suppressor functions of INK4a have been compensated for by other genes. PMID:12506196

  5. The D4A Digitiser

    NASA Astrophysics Data System (ADS)

    de Cuyper, J.-P.; Winter, L.; Vanommeslaeghe, J.

    2004-07-01

    The aim of the pilot-project "Digital Access to Aero- and Astrophotographic Archives - D4A" is to preserve the historic-scientific information contained in the aerial photographic archives of the National Geographical Institute and the Royal Museum of Central Africa, and in the astrophotographic plate archive of the Royal Observatory of Belgium. In collaboration with the astronomical institutes of the Vrije Universiteit Brussel and the Universiteit Antwerpen, and AGFA-Gevaert, a world-leader in photographic matters, the goal is to acquire the necessary know-how, hardware and software to digitise the information contained in the photographic plates, as well as the associated metadata. The project set out to offer the results to the public and to make them directly usable for scientific research through the modern techniques of the information society. A digital catalogue is under construction as well as an air-bearing digitiser of high geometric and radiometric resolution and precision. This digitiser will be housed in a temperature and humidity stabilised clean room with adjacent archive room.

  6. Bidirectional RNA helicase activity of eucaryotic translation initiation factors 4A and 4F.

    PubMed Central

    Rozen, F; Edery, I; Meerovitch, K; Dever, T E; Merrick, W C; Sonenberg, N

    1990-01-01

    The mechanism of ribosome binding to eucaryotic mRNAs is not well understood, but it requires the participation of eucaryotic initiation factors eIF-4A, eIF-4B, and eIF-4F and the hydrolysis of ATP. Evidence has accumulated in support of a model in which these initiation factors function to unwind the 5'-proximal secondary structure in mRNA to facilitate ribosome binding. To obtain direct evidence for initiation factor-mediated RNA unwinding, we developed a simple assay to determine RNA helicase activity, and we show that eIF-4A or eIF-4F, in combination with eIF-4B, exhibits helicase activity. A striking and unprecedented feature of this activity is that it functions in a bidirectional manner. Thus, unwinding can occur either in the 5'-to-3' or 3'-to-5' direction. Unwinding in the 5'-to-3' direction by eIF-4F (the cap-binding protein complex), in conjunction with eIF-4B, was stimulated by the presence of the RNA 5' cap structure, whereas unwinding in the 3'-to-5' direction was completely cap independent. These results are discussed with respect to cap-dependent versus cap-independent mechanisms of ribosome binding to eucaryotic mRNAs. Images PMID:2304461

  7. Targeting the MIR34C-5p-ATG4B-autophagy axis enhances the sensitivity of cervical cancer cells to pirarubicin.

    PubMed

    Wu, Yaran; Ni, Zhenhong; Yan, Xiaojing; Dai, Xufang; Hu, Changjiang; Zheng, Yingru; He, Fengtian; Lian, Jiqin

    2016-07-02

    Pirarubicin (THP) is a newer generation anthracycline anticancer drug. In the clinic, THP and THP-based combination therapies have been demonstrated to be effective against various tumors without severe side effects. However, previous clinical studies have shown that most patients with cervical cancer are not sensitive to THP treatment, and the associated mechanisms are not clear. Consistent with the clinical study, we confirmed that cervical cancer cells were resistant to THP in vitro and in vivo. Our data demonstrated that THP induced a protective macroautophagy/autophagy response in cervical cancer cells, and suppression of this autophagy dramatically enhanced the cytotoxicity of THP. By scanning the mRNA level change of autophagy-related genes, we found that the upregulation of ATG4B (autophagy-related 4B cysteine peptidase) plays an important role in THP-induced autophagy. Moreover, THP increased the mRNA level of ATG4B in cervical cancer cells by promoting mRNA stability without influencing its transcription. Furthermore, THP triggered a downregulation of MIR34C-5p, which was associated with the upregulation of ATG4B and autophagy induction. Overexpression of MIR34C-5p significantly decreased the level of ATG4B and attenuated autophagy, accompanied by enhanced cell death and apoptosis in THP-treated cervical cancer cells. These results for the first time reveal the presence of a MIR34C-5p-ATG4B-autophagy signaling axis in THP-treated cervical cancer cells in vitro and in vivo, and the axis, at least partially, accounts for the THP nonsensitivity in cervical cancer patients. This study may provide a new insight for improving the chemotherapeutic effect of THP, which may be beneficial to the further clinical application of THP in cervical cancer treatment.

  8. Excellent Temperature Performance of Spherical LiFePO4/C Composites Modified with Composite Carbon and Metal Oxides

    PubMed Central

    Zhang, Bao; Zeng, Tao; Zhang, Jiafeng; Peng, Chunli; Zheng, Junchao; Chen, Guomin

    2014-01-01

    Nanosized spherical LiFePO4/C composite was synthesized from nanosized spherical FePO4·2H2O, Li2C2O4, aluminum oxide, titanium oxide, oxalic acid, and sucrose by binary sintering process. The phases and morphologies of LiFePO4/C were characterized using SEM, TEM, CV, EIS, EDS, and EDX as well as charging and discharging measurements. The results showed that the as-prepared LiFePO4/C composite with good conductive webs from nanosized spherical FePO4·2H2O exhibits excellent electrochemical performances, delivering an initial discharge capacity of 161.7 mAh·g−1 at a 0.1 C rate, 152.4 mAh·g−1 at a 1 C rate and 131.7 mAh·g−1 at a 5 C rate, and the capacity retention of 99.1%, 98.7%, and 95.8%, respectively, after 50 cycles. Meanwhile, the high and low temperature performance is excellent for 18650 battery, maintaining capacity retention of 101.7%, 95.0%, 88.3%, and 79.3% at 55°C, 0°C, −10°C, and −20°C by comparison withthat of room temperature (25°C) at the 0.5 C rate over a voltage range of 2.2 V to 3.6 V, respectively. PMID:24526888

  9. Excellent temperature performance of spherical LiFePO4/C composites modified with composite carbon and metal oxides.

    PubMed

    Zhang, Bao; Zeng, Tao; Zhang, Jiafeng; Peng, Chunli; Zheng, Junchao; Chen, Guomin

    2014-01-01

    Nanosized spherical LiFePO4/C composite was synthesized from nanosized spherical FePO4 ·2H2O, Li2C2O4, aluminum oxide, titanium oxide, oxalic acid, and sucrose by binary sintering process. The phases and morphologies of LiFePO4/C were characterized using SEM, TEM, CV, EIS, EDS, and EDX as well as charging and discharging measurements. The results showed that the as-prepared LiFePO4/C composite with good conductive webs from nanosized spherical FePO4 ·2H2O exhibits excellent electrochemical performances, delivering an initial discharge capacity of 161.7 mAh·g(-1) at a 0.1 C rate, 152.4 mAh·g(-1) at a 1 C rate and 131.7 mAh·g(-1) at a 5 C rate, and the capacity retention of 99.1%, 98.7%, and 95.8%, respectively, after 50 cycles. Meanwhile, the high and low temperature performance is excellent for 18650 battery, maintaining capacity retention of 101.7%, 95.0%, 88.3%, and 79.3% at 55°C, 0°C, -10°C, and -20°C by comparison withthat of room temperature (25°C) at the 0.5 C rate over a voltage range of 2.2 V to 3.6 V, respectively.

  10. Mistargeting of SH3TC2 away from the recycling endosome causes Charcot-Marie-Tooth disease type 4C.

    PubMed

    Roberts, Rhys C; Peden, Andrew A; Buss, Folma; Bright, Nicholas A; Latouche, Morwena; Reilly, Mary M; Kendrick-Jones, John; Luzio, J Paul

    2010-03-15

    Mutations in the functionally uncharacterized protein SH3TC2 are associated with the severe hereditary peripheral neuropathy, Charcot-Marie-Tooth disease type 4C (CMT4C). Similarly, to other proteins mutated in CMT, a role for SH3TC2 in endocytic membrane traffic has been previously proposed. However, recent descriptions of the intracellular localization of SH3TC2 are conflicting. Furthermore, no clear functional pathogenic mechanisms have so far been proposed to explain why both nonsense and missense mutations in SH3TC2 lead to similar clinical phenotypes. Here, we describe our intracellular localization studies, supported by biochemical and functional data, using wild-type and mutant SH3TC2. We show that wild-type SH3TC2 targets to the intracellular recycling endosome by associating with the small GTPase, Rab11, which is known to regulate the recycling of internalized membrane and receptors back to the plasma membrane. Furthermore, we demonstrate that SH3TC2 interacts preferentially with the GTP-bound form of Rab11, identifying SH3TC2 as a novel Rab11 effector. Of clinical pathological relevance, all SH3TC2 constructs harbouring disease-causing mutations are shown to be unable to associate with Rab11 with consequent loss of recycling endosome localization. Moreover, we show that wild-type SH3TC2, but not mutant SH3TC2, influences transferrin receptor dynamics, consistent with a functional role on the endocytic recycling pathway. Our data therefore implicate mistargeting of SH3TC2 away from the recycling endosome as the fundamental molecular defect that leads to CMT4C.

  11. The effects of fluoride on cell migration, cell proliferation, and cell metabolism in GH4C1 pituitary tumour cells.

    PubMed

    Mendoza-Schulz, A; Solano-Agama, C; Arreola-Mendoza, L; Reyes-Márquez, B; Barbier, O; Del Razo, L M; Mendoza-Garrido, M E

    2009-10-28

    The consumption of drinking water rich in fluoride has toxic effects on the central nervous system. In cell biology research, fluoride is currently used as a phosphatase inhibitor. The aim of the present study was to evaluate the effect of fluoride on different physiological processes in GH4C1 pituitary tumour cells. We used a range of different fluoride concentrations, from levels below normal human serum concentrations (0.23 and 1.2 micromol/L) to those observed in chronically exposed persons (10.7 micromol/L) and above (107 and 1072 micromol/L). Treatment of 10.7 micromol/L fluoride resulted in a discrete induction of DNA synthesis, without a change in cell number. Cell migration, a behaviour stimulated by growth factors, was increased in cells treated with 2.4 micromol/L. At this fluoride concentration, changes in phosphorylation status of both cytoskeletal and cytosolic protein fractions, as well as in actin cytoskeletal arrangements were observed. The GH4C1 fluoride treated cells had significantly less cellular protein than control cells, suggesting an effect of fluoride on hormone secretion and protein synthesis in this endocrine cell. The bioreduction of MTT was significantly increased with a wide range of fluoride concentrations. With the highest fluoride concentration, 1072 micromol/L, all of the analysed parameters were significantly reduced, suggesting that this dose is highly toxic in GH4C1 cells. Our results show that biologically relevant concentrations of fluoride are capable of increasing cell migration in tumour cells, suggesting that exposure to fluoride could stimulate tumour invasion.

  12. Mechanical Properties and Strengthening Mechanisms of Al-15 Pct B4C Composites with Sc and Zr at Elevated Temperatures

    NASA Astrophysics Data System (ADS)

    Qin, Jian; Zhang, Zhan; Chen, X.-Grant

    2016-09-01

    The mechanical properties at ambient and elevated temperatures of two Al-15 vol pct B4C composites, S40 with 0.4 wt pct Sc and SZ40 with 0.4 wt pct Sc and 0.24 wt pct Zr, are investigated during long-term thermal annealing. The presence of large B4C particles in the microscale has a moderate but stable strengthening effect on Al-B4C composites at ambient and elevated temperatures, while the precipitation of nanoscale Al3Sc and Al3(Sc, Zr) in the composite matrix provides a predominate contribution to the composite strength, which is varied by tested temperatures. The Al3Sc precipitates in S40 remain coarsening resistant at 523 K (250 °C), whereas the Al3(Sc, Zr) precipitates in SZ40 are thermally stable at 573 K (300 °C) over 2000 hours of annealing. At higher annealing temperatures (573 K (300 °C) for S40 and 623 K (350 °C) for SZ40), both Al3Sc and Al3(Sc, Zr) precipitates become coarsening with prolonged annealing time. The yield strength of S40 and SZ40 at ambient temperature decreases with the increasing precipitate size, which can be explained by the classical precipitate shearing and Orowan bypass mechanisms. At elevated temperatures [523 K to 623 K (250 °C to 350 °C)], considerably lower yield stresses are observed compared to those at ambient temperature, which invokes a dislocation climb mechanism. The predicted yield strengths at elevated temperatures by the combination of dislocation climb and Orowan models are in good agreement with the experimental data.

  13. Deposition and characterization of B4C/CeO2 multilayers at 6.x nm extreme ultraviolet wavelengths

    NASA Astrophysics Data System (ADS)

    Sertsu, M. G.; Giglia, A.; Brose, S.; Park, D.; Wang, Z. S.; Mayer, J.; Juschkin, L.; Nicolosi, P.

    2016-03-01

    New multilayers of boron carbide/cerium dioxide (B4C/CeO2) combination on silicon (Si) substrate are manufactured to represent reflective-optics candidates for future lithography at 6.x nm wavelength. This is one of only a few attempts to make multilayers of this kind. Combination of several innovative experiments enables detailed study of optical properties, structural properties, and interface profiles of the multilayers in order to open up a room for further optimization of the manufacturing process. The interface profile is visualized by high-angle annular dark-field imaging which provides highly sensitive contrast to atomic number. Synchrotron based at-wavelength extreme ultraviolet (EUV) reflectance measurements near the boron (B) absorption edge allow derivation of optical parameters with high sensitivity to local atom interactions. X-ray reflectivity measurements at Cu-Kalpha (8 keV ) determine the period of multilayers with high in-depth resolution. By combining these measurements and choosing robust nonlinear curve fitting algorithms, accuracy of the results has been significantly improved. It also enables a comprehensive characterization of multilayers. Interface diffusion is determined to be a major cause for the low reflectivity performance. Optical constants of B4C and CeO2 layers are derived in EUV wavelengths. Besides, optical properties and asymmetric thicknesses of inter-diffusion layers (interlayers) in EUV wavelengths near the boron edge are determined. Finally, ideal reflectivity of the B4C/CeO2 combination is calculated by using optical constants derived from the proposed measurements in order to evaluate the potentiality of the design.

  14. Fermi LAT Detection of a GeV Flare from the Blazar 4C +01.28

    NASA Astrophysics Data System (ADS)

    Krauss, Felicia; Carpen, Bryce

    2014-02-01

    The Large Area Telescope (LAT), one of the two instruments on the Fermi Gamma-ray Space Telescope, has observed increasing gamma-ray flux from a source positionally consistent with 4C +01.28 (also known as PKS 1055+018) RA=10h58m29.6052s, Dec=+01d33m58.824s (J2000; Johnston et al. 1995, AJ, 110, 880) at z= 0.888 (Wills and Lynds 1978, ApJS, 36, 317).

  15. PROCESSING, MICROSTRUCTURE AND MECHANICAL PROPERTY CORRELATION IN Al-B4C SURFACE COMPOSITE PRODUCED VIA FRICTION STIR PROCESSING

    SciTech Connect

    Komarasamy, Mageshwari; Mishra, Rajiv S.; Baumann, John A.; Grant, Glenn J.; Hovanski, Yuri

    2013-01-29

    Friction stir processing (FSP) was employed to prepare surface composites (SC) composed of B4C particles in 5024 Al matrix. The processing parameters, such as hole pattern and geometry,and the number of FSP passes, were optimized to obtain uniform powder distribution. The micrographs revealed a homogeneous distribution of the particles with good interfacial bonding. The hardness of the composite was uniform across the processed region which again indicates the uniformity of powder distribution. The modulus of the surface composite was measured using strain gage and showed a significant improvement. This improvement in modulus lies in the load sharing capability from the soft matrix to the hard particles.

  16. An analysis of the deformation approach to calculation of the life of hydrogen impregnated 1Kh16N4B steel in low-cycle fatigue

    SciTech Connect

    Litvin, V.V.; Anan'evskii, V.A.; Mints, A.I.

    1986-01-01

    This paper presents the results of experimental investigations and an analysis of the applicability of the deformation approach for calculation of the life of 1Kh16N4B steel in low-cycle fatigue. Hydrogen impregnation was done with use of cathodic polarization in a special cell with a polarization current density of 35 mA/cm/sup 2/ for 60 min. The test results are presented, and it can be seen that the influence of hydrogen absorption significantly changes the life of 1Kh16N4B steel, but the Coffin-Kavomoto criterion does not give satisfactory results.

  17. Rapid, Microwave Accelerated Synthesis of [1,2,4]Triazolo[3,4-b][1,3,4]oxadiazoles from 4-Acylamino-1,2,4-Triazoles.

    PubMed

    Breunig, Stesphanie L; Olson, Margaret E; Harki, Daniel A

    2016-09-07

    1,2,4-Triazoles and 1,3,4-oxadiazoles are prevalent moieties in pharmaceutical agents, yet fused [1,2,4]-triazolo[3,4-b][1,3,4]oxadiazoles are surprisingly under-represented for both synthesis and biological application. We report a rapid, two-step synthesis of [1,2,4]-triazolo[3,4-b][1,3,4]oxadiazoles from commercial 4-amino-1,2,4-triazoles that is highlighted by a microwave accelerated intramolecular cyclization to generate the fused ring system. Our efforts to optimize reaction conditions and elucidate reaction mechanism are also described.

  18. Synthesis and biological evaluation of 3,6-diamino-1H-pyrazolo[3,4-b]pyridine derivatives as protein kinase inhibitors.

    PubMed

    Chioua, Mourad; Samadi, Abdelouahid; Soriano, Elena; Lozach, Olivier; Meijer, Laurent; Marco-Contelles, José

    2009-08-15

    The synthesis and biological evaluation of a number of differently substituted 3,6-diamino-1H-pyrazolo[3,4-b]pyridine derivatives are reported. From the inhibition results on a selection of disease-relevant protein kinases [IC(50) (microM) DYRK1A=11; CDK5=0.41; GSK-3=1.5] we have observed that 3,6-diamino-4-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile (4) constitutes a potential new and simple lead compound in the search of drugs for the treatment of Alzheimer's disease.

  19. Stem cells with FGF4-bFGF fused gene enhances the expression of bFGF and improves myocardial repair in rats

    SciTech Connect

    Chen, Xiang-Qi; Chen, Liang-Long Fan, Lin; Fang, Jun; Chen, Zhao-Yang; Li, Wei-Wei

    2014-04-25

    Highlights: • BFGF exists only in the cytoplasm of live cells. • BFGF cannot be secreted into the extracellular space to promote cell growth. • We combine the secretion-promoting signal peptide of FGF4. • We successfully modified BMSCs with the fused genes of FGF4-bFGF. • We promoted the therapeutic effects of transplanted BMSCs in myocardial infarction. - Abstract: The aim of this study was to investigate whether the modification of bone marrow-derived mesenchymal stem cells (BMSCs) with the fused FGF4 (fibroblast growth factor 4)-bFGF (basic fibroblast growth factor) gene could improve the expression and secretion of BFGF, and increase the efficacies in repairing infarcted myocardium. We used In-Fusion technique to construct recombinant lentiviral vectors containing the individual gene of bFGF, enhanced green fluorescent protein (EGFP), or genes of FGF4-bFGF and EGFP, and then transfected these lentiviruses into rat BMSCs. We conducted an in vitro experiment to compare the secretion of bFGF in BMSCs infected by these lentiviruses and also examined their therapeutic effects in the treatment of myocardial infraction in a rodent study. Sixty rats were tested in the following five conditions: Group-SHAM received only sham operation as controls; Group-AMI received only injection of placebo PBS buffer; Group-BMSC, Group-bFGF and Group-FGF4-bFGF received implantation of BMSCs with empty lentivirus, bFGF lentivirus, and FGF4-bFGF lentivirus, respectively. Our results found out that the transplanted FGF4-bFGF BMSCs had the highest survival rate, and also the highest myocardial expression of bFGF and microvascular density as evidenced by Western blotting and immunohistochemistry, respectively. As compared to other groups, the Group-FGF4-BFGF rats had the lowest myocardial fibrotic fraction, and the highest left ventricular ejection fraction. These results suggest that the modification of BMSCs with the FGF4-bFGF fused gene can not only increase the expression of

  20. Up-regulation of Vps4A promotes neuronal apoptosis after intracerebral hemorrhage in adult rats.

    PubMed

    Ren, Jianbing; Yuan, Debin; Xie, Lili; Tao, Xuelei; Duan, Chenwei; Bao, Yifeng; He, Yunfeng; Ge, Jianbin; Lu, Hongjian

    2017-04-01

    Vps4, vacuolar protein sorting 4, belongs to ATPases Associated with diverse cellular Activities (AAA) protein family which is made up of Vps4A and Vps4B. Previous studies demonstrated that Vps4A plays vital roles in diverse aspects such as virus budding, the efficient transport of H-Ras to the PM (plasma membrane) and the involvement in the MVB (multivesiculate bodies) pathway. Interestingly, Vps4A is also expressed in the brain. However, the distribution and function of Vps4A in ICH diseases remain unclear. In this study, we show that Vps4A may be involved in neuronal apoptosis during pathophysiological processes of intracerebral hemorrhage (ICH). Based on the results of Western blot and immunohistochemistry, we found a remarkable up-regulation of Vps4A expression surrounding the hematoma after ICH. Double labeled immunofluorescence showed that Vps4A was co-expressed with NeuN but rarely with astrocytes and microglia. Morever, we detected that neuronal apoptosis marker active caspase-3 had co-localizations with Vps4A. Additionaly, Vps4A knockdown in vitro specifically leads to decreasing neuronal apoptosis coupled with increased Akt phosphorylation. All datas suggested that Vps4A was involved in promoting neuronal apoptosis via inhibiting Akt phosphorylation after ICH.

  1. Detecting long-range chromatin interactions using the chromosome conformation capture sequencing (4C-seq) method.

    PubMed

    Gheldof, Nele; Leleu, Marion; Noordermeer, Daan; Rougemont, Jacques; Reymond, Alexandre

    2012-01-01

    Eukaryotic transcription is tightly regulated by transcriptional regulatory elements, even though these elements may be located far away from their target genes. It is now widely recognized that these regulatory elements can be brought in close proximity through the formation of chromatin loops, and that these loops are crucial for transcriptional regulation of their target genes. The chromosome conformation capture (3C) technique presents a snapshot of long-range interactions, by fixing physically interacting elements with formaldehyde, digestion of the DNA, and ligation to obtain a library of unique ligation products. Recently, several large-scale modifications to the 3C technique have been presented. Here, we describe chromosome conformation capture sequencing (4C-seq), a high-throughput version of the 3C technique that combines the 3C-on-chip (4C) protocol with next-generation Illumina sequencing. The method is presented for use in mammalian cell lines, but can be adapted to use in mammalian tissues and any other eukaryotic genome.

  2. Neutron reflectometry on highly absorbing films and its application to 10B4C-based neutron detectors

    PubMed Central

    Piscitelli, F.; Khaplanov, A.; Devishvili, A.; Schmidt, S.; Höglund, C.; Birch, J.; Dennison, A. J. C.; Gutfreund, P.; Hall-Wilton, R.; Van Esch, P.

    2016-01-01

    Neutron reflectometry is a powerful tool used for studies of surfaces and interfaces. The absorption in the typical studied materials is neglected and this technique is limited only to the reflectivity measurement. For strongly absorbing nuclei, the absorption can be directly measured by using the neutron-induced fluorescence technique which exploits the prompt particle emission of absorbing isotopes. This technique is emerging from soft matter and biology where highly absorbing nuclei, in very small quantities, are used as a label for buried layers. Nowadays, the importance of absorbing layers is rapidly increasing, partially because of their application in neutron detection; a field that has become more active also due to the 3He-shortage. We extend the neutron-induced fluorescence technique to the study of layers of highly absorbing materials, in particular 10B4C. The theory of neutron reflectometry is a commonly studied topic; however, when a strong absorption is present the subtle relationship between the reflection and the absorption of neutrons is not widely known. The theory for a general stack of absorbing layers has been developed and compared to measurements. We also report on the requirements that a 10B4C layer must fulfil in order to be employed as a converter in neutron detection. PMID:26997902

  3. Effects of Nb-doped on the structure and electrochemical performance of LiFePO4/C composites

    NASA Astrophysics Data System (ADS)

    Ma, Zhipeng; Shao, Guangjie; Wang, Guiling; Zhang, Ying; Du, Jianping

    2014-02-01

    The olivine-type niobium doping Li1-xNbxFePO4/C (x=0, 0.005, 0.010, 0.015, 0.025) cathode materials were synthesized via a two-step ball milling solid state reaction. The effects of Nb doping were charactered by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), galvanostatic intermittent titration technique (GITT), cyclic voltammetry (CV), electrochemical impedance spectra (EIS) and galvanostatic charge-discharge. It is found that Nb doping enlarges the interplanar distance of crystal plane parallel to [0 1 0] direction in LiFePO4. In other words, it widens the one dimensional diffusion channels of Li+ along the [0 1 0] direction. Electrochemical test results indicate that the Li0.99Nb0.01FePO4/C composite exhibits the best electrochemical performance with initial special discharge capacity of 139.3 mA h g-1 at 1 C rate. The present synthesis route is promising in making the solid state reaction method more practical for preparation of the LiFePO4 material.

  4. Synthesis and characterization of magnetically recyclable Ag nanoparticles immobilized on Fe3O4@C nanospheres with catalytic activity

    NASA Astrophysics Data System (ADS)

    Li, Wei-hong; Yue, Xiu-ping; Guo, Chang-sheng; Lv, Jia-pei; Liu, Si-si; Zhang, Yuan; Xu, Jian

    2015-04-01

    A novel approach for the synthesis of Ag-loaded Fe3O4@C nanospheres (Ag-Fe3O4@C) was successfully developed. The catalysts possessed a carbon-coated magnetic core and grew active silver nanoparticles on the outer shell using hydrazine monohydrate as the AgNO3 reductant in ethanol. The morphology, inner structure, and magnetic properties of the as-prepared composites were studied with transmission electron microscopy (TEM), X-ray powder diffraction (XRD), fourier translation infrared spectroscopy (FT-IR), and vibrating sample magnetometer (VSM) techniques. Catalytic activity was investigated by degrading rhodamine B (RhB) in the designed experiment. The obtained products were monodispersed and bifunctional with high magnetization, as well as exhibited excellent catalytic activity toward organic dye with 98% of RhB conversion within 20 min in the presence of NaBH4. The product also exhibited convenient magnetic separability and maintained high catalytic activity after six cycle runs.

  5. Zoom-climb altitude maximization of the F-4C and F-15 aircraft for stratospheric sampling missions

    NASA Technical Reports Server (NTRS)

    Hague, D. S.; Merz, A. W.; Page, W. A.

    1976-01-01

    Some predictions indicate that byproducts of aerosol containers may lead to a modification of the ultraviolet-radiation shielding properties of the upper atmosphere. NASA currently monitors atmospheric properties to 70,000 feet using U-2 aircraft. Testing is needed at about 100,000 feet for adequate monitoring of possible aerosol contaminants during the next decade. To study this problem the F-4C and F-15 aircraft were analyzed to determine their maximum altitude ability in zoom-climb maneuvers. These trajectories must satisfy realistic dynamic pressure and Mach number constraints. Maximum altitudes obtained for the F4-C are above 90,000 feet, and for the F-15 above 100,000 feet. Sensitivities of the zoom-climb altitudes were found with respect to several variables including vehicle thrust, initial weight, stratospheric winds and the constraints. A final decision on aircraft selection must be based on mission modification costs and operational considerations balanced against their respective zoom altitude performance capabilities.

  6. Optical and structural characterization of CeO2/B4C multilayers near boron K-edge energy

    NASA Astrophysics Data System (ADS)

    Sertsu, M. G.; Giglia, A.; Brose, S.; Comisso, A.; Wang, Z. S.; Juschkin, L.; Nicolosi, P.

    2015-05-01

    A search for novel materials for making multilayers of high reflectivity has been driven by the vigorous demand towards miniaturizing photonics. A typical consumer of high performance multilayers (MLs) is the extreme ultraviolet lithography (EUVL) based on the 13.5 nm laser produced plasma (LPP) source. To sustain "Moore's law" and print fine features below 10 nm on integrated circuits (IC), source of radiation for the EUVL has to shift towards even shorter wavelengths where 6.x nm wavelength seems to be immediate successor. However, the 6.x nm EUV lithography needs MLs of reflectivity performance above 70 % to support high volume manufacturing (HVM). It is clear that more work is required particularly on the development of MLs with high reflectance, stable to thermal heat and sufficient lifetime. In this work new MLs of B4C/CeO2 are deposited, analyzed and characterized for the first time. Combinations of X-ray reflectometry (XRR) and EUV reflectance measurements near resonance edge of boron are analyzed to derive structural and optical parameters of MLs. ML coatings of B4C/CeO2 MLs have shown similar reflectance performance with the leading candidate MLs around 6.x nm wavelength. Analysis shows that interlayer diffusion is a major reason for low reflectivity performance. Cross-sectional scanning electron microscopy (SEM) images of the MLs have proved formation of interlayer diffusion.

  7. Factor-dependent processivity in human eIF4A DEAD-box helicase

    PubMed Central

    García-García, Cuauhtémoc; Frieda, Kirsten L.; Feoktistova, Kateryna; Fraser, Christopher S.; Block, Steven M.

    2015-01-01

    During eukaryotic translation initiation, the small ribosomal subunit, assisted by initiation factors, locates the messenger RNA start codon by scanning from the 5′ cap. This process is powered by the eukaryotic initiation factor 4A (eIF4A), a DEAD-box helicase. eIF4A has been thought to unwind structures formed in the untranslated 5′ region via a nonprocessive mechanism. Using a single-molecule assay, we found that eIF4A functions instead as an adenosine triphosphate–dependent processive helicase when complexed with two accessory proteins, eIF4G and eIF4B. Translocation occurred in discrete steps of 11 ± 2 base pairs, irrespective of the accessory factor combination. Our findings support a memory-less stepwise mechanism for translation initiation and suggest that similar factor-dependent processivity may be shared by other members of the DEAD-box helicase family. PMID:26113725

  8. Draft Genome Sequences of Pseudomonas fluorescens Strains SF39a and SF4c, Potential Plant Growth Promotion and Biocontrol Agents

    PubMed Central

    Ly, Lindsey K.; Underwood, Grace E.; McCully, Lucy M.; Bitzer, Adam S.; Godino, Agustina; Bucci, Vanni; Brigham, Christopher J.; Príncipe, Analía; Fischer, Sonia E.

    2015-01-01

    Pseudomonas fluorescens SF4c and SF39a, strains isolated from wheat rhizosphere, have potential applications in plant growth promotion and biocontrol of fungal diseases of crop plants. We report the draft genome sequences of SF4c and SF39a with estimated sizes of 6.5 Mb and 5.9 Mb, respectively. PMID:25814613

  9. An AP4B1 frameshift mutation in siblings with intellectual disability and spastic tetraplegia further delineates the AP-4 deficiency syndrome.

    PubMed

    Abdollahpour, Hengameh; Alawi, Malik; Kortüm, Fanny; Beckstette, Michael; Seemanova, Eva; Komárek, Vladimír; Rosenberger, Georg; Kutsche, Kerstin

    2015-02-01

    The recently proposed adaptor protein 4 (AP-4) deficiency syndrome comprises a group of congenital neurological disorders characterized by severe intellectual disability (ID), delayed or absent speech, hereditary spastic paraplegia, and growth retardation. AP-4 is a heterotetrameric protein complex with important functions in vesicle trafficking. Mutations in genes affecting different subunits of AP-4, including AP4B1, AP4E1, AP4S1, and AP4M1, have been reported in patients with the AP-4 deficiency phenotype. We describe two siblings from a non-consanguineous couple who presented with severe ID, absent speech, microcephaly, growth retardation, and progressive spastic tetraplegia. Whole-exome sequencing in the two patients identified the novel homozygous 2-bp deletion c.1160_1161delCA (p.(Thr387Argfs*30)) in AP4B1. Sanger sequencing confirmed the mutation in the siblings and revealed it in the heterozygous state in both parents. The AP4B1-associated phenotype has previously been assigned to spastic paraplegia-47. Identification of a novel AP4B1 alteration in two patients with clinical manifestations highly similar to other individuals with mutations affecting one of the four AP-4 subunits further supports the observation that loss of AP-4 assembly or functionality underlies the common clinical features in these patients and underscores the existence of the clinically recognizable AP-4 deficiency syndrome.

  10. Identification of a novel SBF2 frameshift mutation in charcot-marie-tooth disease type 4B2 using whole-exome sequencing.

    PubMed

    Chen, Meiyan; Wu, Jing; Liang, Ning; Tang, Lihui; Chen, Yanhua; Chen, Huishuang; Wei, Wei; Wei, Tianying; Huang, Hui; Yi, Xin; Qi, Ming

    2014-10-01

    Charcot-Marie-Tooth disease type 4B2 with early-onset glaucoma (CMT4B2, OMIM 604563) is a genetically-heterogeneous childhood-onset neuromuscular disorder. Here, we report the case of a 15-year-old male adolescent with lower extremity weakness, gait abnormalities, foot deformities and early-onset glaucoma. Since clinical diagnosis alone was insufficient for providing pathogenetic evidence to indicate that the condition belonged to a consanguineous family, we applied whole-exome sequencing to samples from the patient, his parents and his younger brother, assuming that the patient's condition is transmitted in an autosomal recessive pattern. A frame-shift mutation, c.4571delG (P.Gly1524Glufs∗42), was revealed in the CMT4B2-related gene SBF2 (also known as MTMR13, MIM 607697), and this mutation was found to be homozygous in the proband and heterozygous in his parents and younger brother. Together with the results of clinical diagnosis, this case was diagnosed as CMT4B2. Our finding further demonstrates the use of whole-exome sequencing in the diagnosis and treatment of rare diseases.

  11. Draft Genome Sequences of Listeria monocytogenes Serotype 4b Strains 944 and 2993 and Serotype 1/2c Strains 198 and 2932

    PubMed Central

    Casey, Aidan; Fox, Edward M.; Leong, Dara; Gahan, Cormac G. M.; Jordan, Kieran

    2016-01-01

    Listeria monocytogenes is a foodborne pathogen and the causative agent of listeriosis among humans and animals. The draft genome sequences of L. monocytogenes serotype 4b strains 944 and 2993 and serotype 1/2c strains 198 and 2932 are reported here. PMID:27257200

  12. First Draft Genome Sequences of Neisseria sp. Strain 83E34 and Neisseria sp. Strain 74A18, Previously Identified as CDC Eugonic Fermenter 4b Species

    PubMed Central

    Greninger, Alexander L.; Streithorst, Jessica

    2016-01-01

    We report the first draft genome sequences of two isolates previously classified as CDC EF-4b species, Neisseria sp. 83E34 and Neisseria sp. 74A18. Both strains were isolated from patients with animal bites and likely constitute novel genomospecies with average nucleotide identities of <95% to other sequenced strains. PMID:27834718

  13. Synergistic effects of sodium chloride, Glucose, and temperature on biofilm formation by Listeria monocytogenes serotype 1/2a and 4b strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biofilm formation by Listeria monocytogenes is generally associated with its persistence in the food processing environment. Serotype 1/2a strains make up more than 50% of the total isolates recovered from food and environment, while serotype 4b strains are most often associated with major outbreaks...

  14. The discovery and structure-activity relationships of pyrano[3,4-b]indole based inhibitors of hepatitis C virus NS5B polymerase.

    PubMed

    LaPorte, Matthew G; Draper, Tandy L; Miller, Lori E; Blackledge, Charles W; Leister, Lara K; Amparo, Eugene; Hussey, Alison R; Young, Dorothy C; Chunduru, Srinivas K; Benetatos, Christopher A; Rhodes, Gerry; Gopalsamy, Ariamala; Herbertz, Torsten; Burns, Christopher J; Condon, Stephen M

    2010-05-01

    We describe the structure-activity relationship of the C1-group of pyrano[3,4-b]indole based inhibitors of HCV NS5B polymerase. Further exploration of the allosteric binding site led to the discovery of the significantly more potent compound 12.

  15. Acquisition of complement inhibitor serine protease factor I and its cofactors C4b-binding protein and factor H by Prevotella intermedia.

    PubMed

    Malm, Sven; Jusko, Monika; Eick, Sigrun; Potempa, Jan; Riesbeck, Kristian; Blom, Anna M

    2012-01-01

    Infection with the Gram-negative pathogen Prevotella intermedia gives rise to periodontitis and a growing number of studies implies an association of P. intermedia with rheumatoid arthritis. The serine protease Factor I (FI) is the central inhibitor of complement degrading complement components C3b and C4b in the presence of cofactors such as C4b-binding protein (C4BP) and Factor H (FH). Yet, the significance of complement inhibitor acquisition in P. intermedia infection and FI binding by Gram-negative pathogens has not been addressed. Here we show that P. intermedia isolates bound purified FI as well as FI directly from heat-inactivated human serum. FI bound to bacteria retained its serine protease activity as shown in degradation experiments with (125)I-labeled C