Science.gov

Sample records for reduces surface expression

  1. Introduced Amino Terminal Epitopes Can Reduce Surface Expression of Neuronal Nicotinic Receptors

    PubMed Central

    Bracamontes, John R.; Akk, Gustav; Steinbach, Joe Henry

    2016-01-01

    Epitopes accessible on the surface of intact cells are extremely valuable in studies of membrane proteins, allowing quantification and determination of the distribution of proteins as well as identification of cells expressing large numbers of proteins. However for many membrane proteins there are no suitable antibodies to native sequences, due to lack of availability, low affinity or lack of specificity. In these cases the use of an introduced epitope at specific sites in the protein of interest can often provide a suitable tool for studies. However, the introduction of the epitope sequence has the potential to affect protein expression, the assembly of multisubunit proteins or transport to the surface membrane. We find that surface expression of heteromeric neuronal nicotinic receptors containing the α4 and β4 subunits can be affected by introduced epitopes when inserted near the amino terminus of a subunit. The FLAG epitope greatly reduces surface expression when introduced into either α4 or β4 subunits, the V5 epitope has little effect when placed in either, while the Myc epitope reduces expression more when inserted into β4 than α4. These results indicate that the extreme amino terminal region is important for assembly of these receptors, and demonstrate that some widely used introduced epitopes may severely reduce surface expression. PMID:26963253

  2. Rare TREM2 variants associated with Alzheimer's disease display reduced cell surface expression.

    PubMed

    Sirkis, Daniel W; Bonham, Luke W; Aparicio, Renan E; Geier, Ethan G; Ramos, Eliana Marisa; Wang, Qing; Karydas, Anna; Miller, Zachary A; Miller, Bruce L; Coppola, Giovanni; Yokoyama, Jennifer S

    2016-01-01

    Rare variation in TREM2 has been associated with greater risk for Alzheimer's disease (AD). TREM2 encodes a cell surface receptor expressed on microglia and related cells, and the R47H variant associated with AD appears to affect the ability of TREM2 to bind extracellular ligands. In addition, other rare TREM2 mutations causing early-onset neurodegeneration are thought to impair cell surface expression. Using a sequence kernel association (SKAT) analysis in two independent AD cohorts, we found significant enrichment of rare TREM2 variants not previously characterized at the protein level. Heterologous expression of the identified variants showed that novel variants S31F and R47C displayed significantly reduced cell surface expression. In addition, we identified rare variant R136Q in a patient with language-predominant AD that also showed impaired surface expression. The results suggest rare TREM2 variants enriched in AD may be associated with altered TREM2 function and that AD risk may be conferred, in part, from altered TREM2 surface expression. PMID:27589997

  3. SRC Inhibition Reduces NR2B Surface Expression and Synaptic Plasticity in the Amygdala

    ERIC Educational Resources Information Center

    Sinai, Laleh; Duffy, Steven; Roder, John C.

    2010-01-01

    The Src protein tyrosine kinase plays a central role in the regulation of N-methyl-d-aspartate receptor (NMDAR) activity by regulating NMDAR subunit 2B (NR2B) surface expression. In the amygdala, NMDA-dependent synaptic plasticity resulting from convergent somatosensory and auditory inputs contributes to emotional memory; however, the role of Src…

  4. Chronic Morphine Reduces Surface Expression of δ-Opioid Receptors in Subregions of Rostral Striatum.

    PubMed

    Leah, Paul M; Heath, Emily M L; Balleine, Bernard W; Christie, Macdonald J

    2016-03-01

    The delta opioid receptor (DOPr), whilst not the primary target of clinically used opioids, is involved in development of opioid tolerance and addiction. There is growing evidence that DOPr trafficking is involved in drug addiction, e.g., a range of studies have shown increased plasma membrane DOPr insertion during chronic treatment with opioids. The present study used a transgenic mouse model in which the C-terminal of the DOPr is tagged with enhanced-green fluorescence protein to examine the effects of chronic morphine treatment on surface membrane expression in striatal cholinergic interneurons that are implicated in motivated learning following both chronic morphine and morphine sensitization treatment schedules in male mice. A sex difference was noted throughout the anterior striatum, which was most prominent in the nucleus accumbens core region. Incontrast with previous studies in other neurons, chronic exposure to a high dose of morphine for 6 days had no effect, or slightly decreased (anterior dorsolateral striatum) surface DOPr expression. A morphine sensitization schedule produced similar results with a significant decrease in surface DOPr expression in nucleus accumbens shell. These results suggest that chronic morphine and morphine sensitisation treatment may have effects on instrumental reward-seeking behaviours and learning processes related to drug addiction, via effects on striatal DOPr function. PMID:26093651

  5. Cognitive decline is associated with reduced surface GluR1 expression in the hippocampus of aged rats.

    PubMed

    Yang, Yuan-Jian; Chen, Hai-Bo; Wei, Bo; Wang, Wei; Zhou, Ping-Liang; Zhan, Jin-Qiong; Hu, Mao-Rong; Yan, Kun; Hu, Bin; Yu, Bin

    2015-03-30

    Individual differences in cognitive aging exist in humans and in rodent populations, yet the underlying mechanisms remain largely unclear. Activity-dependent delivery of GluR1-containing AMPA receptor (AMPARs) plays an essential role in hippocampal synaptic plasticity, learning and memory. We hypothesize that alterations of surface GluR1 expression in the hippocampus might correlate with age-related cognitive decline. To test this hypothesis, the present study evaluated the cognitive function of young adult and aged rats using Morris water maze. After the behavioral test, the surface expression of GluR1 protein in hippocampal CA1 region of rats was determined using Western blotting. The results showed that the surface expression of GluR1 in the hippocampus of aged rats that are cognitively impaired was much lower than that of young adults and aged rats with preserved cognitive abilities. The phosphorylation levels of GluR1 at Ser845 and Ser831 sites, which promote the synaptic delivery of GluR1, were also selectively decreased in the hippocampus of aged-impaired rats. Correlation analysis reveals that greater decrease in surface GluR1 expression was associated with worse behavioral performance. These results suggest that reduced surface GluR1 expression may contribute to cognitive decline that occurs in normal aging, and different pattern of surface GluR1 expression might be responsible for the individual differences in cognitive aging. PMID:25697598

  6. A novel thromboxane A2 receptor N42S variant results in reduced surface expression and platelet dysfunction.

    PubMed

    Nisar, Shaista P; Lordkipanidzé, Marie; Jones, Matthew L; Dawood, Ban; Murden, Sherina; Cunningham, Margaret R; Mumford, Andrew D; Wilde, Jonathan T; Watson, Steve P; Mundell, Stuart J; Lowe, Gillian C

    2014-05-01

    A small number of thromboxane receptor variants have been described in patients with a bleeding history that result in platelet dysfunction. We have identified a patient with a history of significant bleeding, who expresses a novel heterozygous thromboxane receptor variant that predicts an asparagine to serine substitution (N42S). This asparagine is conserved across all class A GPCRs, suggesting a vital role for receptor structure and function.We investigated the functional consequences of the TP receptor heterozygous N42S substitution by performing platelet function studies on platelet-rich plasma taken from the patient and healthy controls. We investigated the N42S mutation by expressing the wild-type (WT) and mutant receptor in human embryonic kidney (HEK) cells. Aggregation studies showed an ablation of arachidonic acid responses in the patient, whilst there was right-ward shift of the U46619 concentration response curve (CRC). Thromboxane generation was unaffected. Calcium mobilisation studies in cells lines showed a rightward shift of the U46619 CRC in N42S-expressing cells compared to WT. Radioligand binding studies revealed a reduction in BMax in platelets taken from the patient and in N42S-expressing cells, whilst cell studies confirmed poor surface expression. We have identified a novel thromboxane receptor variant, N42S, which results in platelet dysfunction due to reduced surface expression. It is associated with a significant bleeding history in the patient in whom it was identified. This is the first description of a naturally occurring variant that results in the substitution of this highly conserved residue and confirms the importance of this residue for correct GPCR function. PMID:24452735

  7. Functionally Responsive Self-Reactive B Cells of Low-Affinity Express Reduced Levels of Surface IgM1

    PubMed Central

    Kirchenbaum, Greg A.; St. Clair, James B.; Detanico, Thiago; Aviszus, Katja; Wysocki, Lawrence J.

    2014-01-01

    SUMMARY Somatic gene rearrangement generates a diverse repertoire of B cells, including B cell receptors (BCR) possessing a range of affinities for self-Ag. Newly generated B cells express high and relatively uniform amounts of surface IgM (sIgM), while follicular (FO) B cells express sIgM at widely varying levels. It is plausible, therefore, that down-modulation of sIgM serves as a mechanism to maintain weakly self-reactive B cells in a responsive state by decreasing their avidity for self-Ag. We tested this hypothesis by performing comparative functional tests with FO IgMhi and IgMlo B cells from the unrestricted repertoire of wildtype (WT) mice. We found that FO IgMlo B cells mobilized Ca2+ equivalently to IgMhi B cells when the same number of sIgM molecules was engaged. In agreement, FO IgMlo B cells were functionally competent to produce an antibody response following adoptive transfer. The FO IgMlo cell population had elevated levels of Nur77 transcript, and was enriched with nuclear-reactive specificities. Hybridoma sampling revealed that these BCR were of low affinity. Collectively, these results suggest that sIgM down-modulation by low-affinity, self-reactive B cells preserves their immunocompetence and circumvents classical peripheral tolerance mechanisms that would otherwise reduce diversity within the B cell compartment. PMID:24375379

  8. Heterologous expression of rab4 reduces glucose transport and GLUT4 abundance at the cell surface in oocytes.

    PubMed Central

    Mora, S; Monden, I; Zorzano, A; Keller, K

    1997-01-01

    To evaluate the role of the small rab GTP-binding proteins in glucose transporter trafficking, we have heterologously co-expressed rab4 or rab5 and GLUT4 or GLUT1 glucose transporters in Xenopus oocytes. Co-injection of rab4 and GLUT4 cRNAs resulted in a dose-dependent decrease in glucose transport; this effect was specific for rab4, since co-injection of an inactive rab4 mutant or rab5 cRNA did not have any effect on glucose transport. The effect of rab4 was selective for GLUT4, since no effect was detected in GLUT1-expressing oocytes. The inhibitory effect of rab4 on GLUT4-induced glucose transport was not the result of a change in overall cellular levels of GLUT4 glucose transporters. However, rab4 expression caused a marked decrease in the abundance of GLUT4 transporters present at the cell surface. Finally, rab4 and inhibitors of PtdIns 3-kinase showed additive effects in decreasing glucose transport in GLUT4-expressing oocytes. We conclude that rab4 plays an important role in the regulation of the intracellular GLUT4 trafficking pathway, by contributing to the intracellular retention of GLUT4 through a PtdIns 3-kinase-independent mechanism. PMID:9182703

  9. Reducing Xanthomonas from surfaces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Removal of the citrus canker organism, Xanthomonas axonopodis pv citri , from the surfaces of packinglines is just as important an issue facing the citrus fresh fruit packers as removing the bacteria from the fruit surfaces. Current allowable washes and rinses do not adequately clean the lines and ...

  10. Identification of Two Intracellular Mechanisms Leading to Reduced Expression of Oncoretrovirus Envelope Glycoproteins at the Cell Surface

    PubMed Central

    Grange, Marie-Pierre; Blot, Vincent; Delamarre, Lelia; Bouchaert, Isabelle; Rocca, Anna; Dautry-Varsat, Alice; Dokhélar, Marie-Christine

    2000-01-01

    All retrovirus glycoproteins have a cytoplasmic domain that plays several roles in virus replication. We have determined whether and how the cytoplasmic domains of oncoretrovirus glycoproteins modulate their intracellular trafficking, by using chimeric proteins that combined the α-chain of the interleukin-2 receptor with the glycoprotein cytoplasmic domains of five oncoretroviruses: human T-cell leukemia virus type 1 (HTLV-1), Rous sarcoma virus (RSV), bovine leukemia virus (BLV), murine leukemia virus (MuLV), and Mason-Pfizer monkey virus (MPMV). All of these proteins were synthesized and matured in the same way as a control protein with no retrovirus cytoplasmic domain. However, the amounts of all chimeric proteins at the cell surface were smaller than that of the control protein. The protein appearing at and leaving the cell surface and endocytosis were measured in stable transfectants expressing the chimera. We identified two groups of proteins which followed distinct intracellular pathways. Group 1 included chimeric proteins that reached the cell surface normally but were rapidly endocytosed afterwards. This group included the chimeric proteins with HTLV-1, RSV, and BLV cytoplasmic domains. Group 2 included chimeric proteins that were not detected at the cell surface, despite normal intracellular concentrations, and were accumulated in the Golgi complex. This group included the chimeric proteins with MuLV and MPMV cytoplasmic domains. Finally, we verified that the MuLV envelope glycoproteins behaved in the same way as the corresponding chimeras. These results indicate that retroviruses have evolved two distinct mechanisms to ensure a similar biological feature: low concentrations of their glycoproteins at the cell surface. PMID:11090173

  11. Mutations in GFPT1 that underlie limb-girdle congenital myasthenic syndrome result in reduced cell-surface expression of muscle AChR.

    PubMed

    Zoltowska, Katarzyna; Webster, Richard; Finlayson, Sarah; Maxwell, Susan; Cossins, Judith; Müller, Juliane; Lochmüller, Hanns; Beeson, David

    2013-07-15

    Mutations in GFPT1 underlie a congenital myasthenic syndrome (CMS) characterized by a limb-girdle pattern of muscle weakness. Glutamine-fructose-6-phosphate transaminase 1 (GFPT1) is a key rate-limiting enzyme in the hexosamine biosynthetic pathway providing building blocks for the glycosylation of proteins and lipids. It is expressed ubiquitously and it is not readily apparent why mutations in this gene should cause a syndrome with symptoms restricted to muscle and, in particular, to the neuromuscular junction. Data from a muscle biopsy obtained from a patient with GFPT1 mutations indicated that there were reduced endplate acetylcholine receptors. We, therefore, further investigated the relationship between identified mutations in GFPT1 and expression of the muscle acetylcholine receptor. Cultured myotubes derived from two patients with GFPT1 mutations showed a significant reduction in cell-surface AChR expression (Pt1 P < 0.0001; Pt2 P = 0.0097). Inhibition of GFPT1 enzymatic activity or siRNA silencing of GFPT1 expression both resulted in reduced AChR cell-surface expression. Western blot and gene-silencing experiments indicate this is due to reduced steady-state levels of AChR α, δ, ε, but not β subunits rather than altered transcription of AChR-subunit RNA. Uridine diphospho-N-acetylglucosamine, a product of the hexosamine synthetic pathway, acts as a substrate at an early stage in the N-linked glycosylation pathway. Similarity between CMS due to GFPT1 mutations and CMS due to DPAGT1 mutations would suggest that reduced endplate AChR due to defective N-linked glycosylation is a primary disease mechanism in this disorder. PMID:23569079

  12. Ethanol reduces GABAA alpha1 subunit receptor surface expression by a protein kinase Cgamma-dependent mechanism in cultured cerebral cortical neurons.

    PubMed

    Kumar, Sandeep; Suryanarayanan, Asha; Boyd, Kevin N; Comerford, Chris E; Lai, Marvin A; Ren, Qinglu; Morrow, A Leslie

    2010-05-01

    Prolonged ethanol exposure causes central nervous system hyperexcitability that involves a loss of GABAergic inhibition. We previously demonstrated that long-term ethanol exposure enhances the internalization of synaptic GABA(A) receptors composed of alpha1beta2/3gamma2 subunits. However, the mechanisms of ethanol-mediated internalization are unknown. This study explored the effect of ethanol on surface expression of GABA(A) alpha1 subunit-containing receptors in cultured cerebral cortical neurons and the role of protein kinase C (PKC) beta, gamma, and epsilon isoforms in their trafficking. Cultured neurons were prepared from rat pups on postnatal day 1 and maintained for 18 days. Cells were exposed to ethanol, and surface receptors were isolated by biotinylation and P2 fractionation, whereas functional analysis was conducted by whole-cell patch-clamp recording of GABA- and zolpidem-evoked responses. Ethanol exposure for 4 h decreased biotinylated surface expression of GABA(A) receptor alpha1 subunits and reduced zolpidem (100 nM) enhancement of GABA-evoked currents. The PKC activator phorbol-12,13-dibutyrate mimicked the effect of ethanol, and the selective PKC inhibitor calphostin C prevented ethanol-induced internalization of these receptors. Ethanol exposure for 4 h also increased the colocalization and coimmunoprecipitation of PKCgamma with alpha1 subunits, whereas PKCbeta/alpha1 association and PKCepsilon/alpha1 colocalization were not altered by ethanol exposure. Selective PKCgamma inhibition by transfection of selective PKCgamma small interfering RNAs blocked ethanol-induced internalization of GABA(A) receptor alpha1 subunits, whereas PKCbeta inhibition using pseudo-PKCbeta had no effect. These findings suggest that ethanol exposure selectively alters PKCgamma translocation to GABA(A) receptors and PKCgamma regulates GABA(A) alpha1 receptor trafficking after ethanol exposure. PMID:20159950

  13. Cell surface engineering of renal cell carcinoma with glycosylphosphatidylinositol-anchored TIMP-1 blocks TGF- β 1 activation and reduces regulatory ID gene expression.

    PubMed

    Notohamiprodjo, Susan; Djafarzadeh, Roghieh; Rieth, Nicole; Hofstetter, Monika; Jaeckel, Carsten; Nelson, Peter J

    2012-12-01

    Tissue inhibitor of metalloproteinase 1 (TIMP-1) controls matrix metalloproteinase activity through 1:1stoichiometric binding. Human TIMP-1 fused to a glycosylphosphatidylinositol(GPI) anchor (TIMP-1 - GPI) shifts the activity of TIMP-1 from the extracellular matrix to the cell surface. TIMP-1 - GPI treated renal cell carcinoma cells show increased apoptosis and reduced proliferation.Transcriptomic profiling and regulatory pathway mapping were used to identify the potential mechanisms driving these effects. Significant changes in the DNA binding inhibitors, TGF- β 1/SMAD and BMP pathways resulted from TIMP-1 - GPI treatment. These events were linked to reduced TGF- β 1 signaling mediated by inhibition of proteolytic processing of latent TGF- β 1 by TIMP-1 - GPI. PMID:23667903

  14. Hypoxia facilitates tumour cell detachment by reducing expression of surface adhesion molecules and adhesion to extracellular matrices without loss of cell viability.

    PubMed Central

    Hasan, N. M.; Adams, G. E.; Joiner, M. C.; Marshall, J. F.; Hart, I. R.

    1998-01-01

    The effects of acute hypoxia on integrin expression and adhesion to extracellular matrix proteins were investigated in two human melanoma cell lines, HMB-2 and DX3, and a human adenocarcinoma cell line, HT29. Exposure to hypoxia caused a significant down-regulation of cell surface integrins and an associated decrease in cell adhesion. Loss of cell adhesion and integrin expression were transient and levels returned to normal within 24 h of reoxygenation. Other cell adhesion molecules, such as CD44 and N-CAM, were also down-regulated after exposure of cells to hypoxia. Acute exposure to hypoxia of cells at confluence caused rapid cell detachment. Cell detachment preceded loss of viability. Detached HMB-2 and DX3 cells completely recovered upon reoxygenation, and floating cells re-attached and continued to grow irrespective of whether they were left in the original glass dishes or transferred to new culture vessels, while detached HT29 cells partly recovered upon reoxygenation. Cell detachment after decreased adhesion appears to be a stress response, which may be a factor enabling malignant cells to escape hypoxia in vivo, with the potential to form new foci of tumour growth. PMID:9667649

  15. Microenvironmental stresses induce HLA-E/Qa-1 surface expression and thereby reduce CD8(+) T-cell recognition of stressed cells.

    PubMed

    Sasaki, Takanori; Kanaseki, Takayuki; Shionoya, Yosuke; Tokita, Serina; Miyamoto, Sho; Saka, Eri; Kochin, Vitaly; Takasawa, Akira; Hirohashi, Yoshihiko; Tamura, Yasuaki; Miyazaki, Akihiro; Torigoe, Toshihiko; Hiratsuka, Hiroyoshi; Sato, Noriyuki

    2016-04-01

    Hypoxia and glucose deprivation are often observed in the microenvironment surrounding solid tumors in vivo. However, how they interfere with MHC class I antigen processing and CD8(+) T-cell responses remains unclear. In this study, we analyzed the production of antigenic peptides presented by classical MHC class I in mice, and showed that it is quantitatively decreased in the cells exposed to either hypoxia or glucose deprivation. In addition, we unexpectedly found increased surface expression of HLA-E in human and Qa-1 in mouse tumor cells exposed to combined oxygen and glucose deprivation. The induced Qa-1 on the stressed tumor model interacted with an inhibitory NKG2/CD94 receptor on activated CD8(+) T cells and attenuated their specific response to the antigen. Our results thus suggest that microenvironmental stresses modulate not only classical but also nonclassical MHC class I presentation, and confer the stressed cells the capability to escape from the CD8(+) T-cell recognition. PMID:26711740

  16. Mutation Linked to Autosomal Dominant Nocturnal Frontal Lobe Epilepsy Reduces Low-Sensitivity α4β2, and Increases α5α4β2, Nicotinic Receptor Surface Expression

    PubMed Central

    Nichols, Weston A.; Henderson, Brandon J.; Marotta, Christopher B.; Yu, Caroline Y.; Richards, Chris; Dougherty, Dennis A.; Lester, Henry A.

    2016-01-01

    A number of mutations in α4β2-containing (α4β2*) nicotinic acetylcholine (ACh) receptors (nAChRs) are linked to autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE), including one in the β2 subunit called β2V287L. Two α4β2* subtypes with different subunit stoichiometries and ACh sensitivities co-exist in the brain, a high-sensitivity subtype with (α4)2(β2)3 subunit stoichiometry and a low-sensitivity subtype with (α4)3(β2)2 stoichiometry. The α5 nicotinic subunit also co-assembles with α4β2 to form a high-sensitivity α5α4β2 nAChR. Previous studies suggest that the β2V287L mutation suppresses low-sensitivity α4β2* nAChR expression in a knock-in mouse model and also that α5 co-expression improves the surface expression of ADNFLE mutant nAChRs in a cell line. To test these hypotheses further, we expressed mutant and wild-type (WT) nAChRs in oocytes and mammalian cell lines, and measured the effects of the β2V287L mutation on surface receptor expression and the ACh response using electrophysiology, a voltage-sensitive fluorescent dye, and superecliptic pHluorin (SEP). The β2V287L mutation reduced the EC50 values of high- and low-sensitivity α4β2 nAChRs expressed in Xenopus oocytes for ACh by a similar factor and suppressed low-sensitivity α4β2 expression. In contrast, it did not affect the EC50 of α5α4β2 nAChRs for ACh. Measurements of the ACh responses of WT and mutant nAChRs expressed in mammalian cell lines using a voltage-sensitive fluorescent dye and whole-cell patch-clamping confirm the oocyte data. They also show that, despite reducing the maximum response, β2V287L increased the α4β2 response to a sub-saturating ACh concentration (1 μM). Finally, imaging SEP-tagged α5, α4, β2, and β2V287L subunits showed that β2V287L reduced total α4β2 nAChR surface expression, increased the number of β2 subunits per α4β2 receptor, and increased surface α5α4β2 nAChR expression. Thus, the β2V287L mutation alters the subunit

  17. Swimming Motility Reduces Deposition to Silica Surfaces

    SciTech Connect

    Lu, Nanxi; Massoudieh, Arash; Liang, Xiaomeng; Hu, Dehong; Kamai, Tamir; Ginn, Timothy R.; Zilles, Julie L.; Nguyen, Thanh H.

    2015-01-01

    The role of swimming motility on bacterial transport and fate in porous media was evaluated. We present microscopic evidence showing that strong swimming motility reduces attachment of Azotobacter vinelandii cells to silica surfaces. Applying global and cluster statistical analyses to microscopic videos taken under non-flow conditions, wild type, flagellated A. vinelandii strain DJ showed strong swimming ability with an average speed of 13.1 μm/s, DJ77 showed impaired swimming averaged at 8.7 μm/s, and both the non-flagellated JZ52 and chemically treated DJ cells were non-motile. Quantitative analyses of trajectories observed at different distances above the collector of a radial stagnation point flow cell (RSPF) revealed that both swimming and non-swimming cells moved with the flow when at a distance of at least 20 μm from the collector surface. Near the surface, DJ cells showed both horizontal and vertical movement diverging them from reaching surfaces, while chemically treated DJ cells moved with the flow to reach surfaces, suggesting that strong swimming reduced attachment. In agreement with the RSPF results, the deposition rates obtained for two-dimensional multiple-collector micromodels were also lowest for DJ, while DJ77 and JZ52 showed similar values. Strong swimming specifically reduced deposition on the upstream surfaces of the micromodel collectors.

  18. Swimming Motility Reduces Deposition to Silica Surfaces.

    PubMed

    Lu, Nanxi; Massoudieh, Arash; Liang, Xiaomeng; Hu, Dehong; Kamai, Tamir; Ginn, Timothy R; Zilles, Julie L; Nguyen, Thanh H

    2015-09-01

    The transport and fate of bacteria in porous media is influenced by physicochemical and biological properties. This study investigated the effect of swimming motility on the attachment of cells to silica surfaces through comprehensive analysis of cell deposition in model porous media. Distinct motilities were quantified for different strains using global and cluster-based statistical analyses of microscopic images taken under no-flow condition. The wild-type, flagellated strain DJ showed strong swimming as a result of the actively swimming subpopulation whose average speed was 25.6 μm/s; the impaired swimming of strain DJ77 was attributed to the lower average speed of 17.4 μm/s in its actively swimming subpopulation; and both the nonflagellated JZ52 and chemically treated DJ cells were nonmotile. The approach and deposition of these bacterial cells were analyzed in porous media setups, including single-collector radial stagnation point flow cells (RSPF) and two-dimensional multiple-collector micromodels under well-defined hydrodynamic conditions. In RSPF experiments, both swimming and nonmotile cells moved with the flow when at a distance ≥20 μm above the collector surface. Closer to the surface, DJ cells showed both horizontal and vertical movement, limiting their contact with the surface, while chemically treated DJ cells moved with the flow to reach the surface. These results explain how wild-type swimming reduces attachment. In agreement, the deposition in micromodels was also lowest for DJ compared with those for DJ77 and JZ52. Wild-type swimming specifically reduced deposition on the upstream surfaces of the micromodel collectors. Conducted under environmentally relevant hydrodynamic conditions, the results suggest that swimming motility is an important characteristic for bacterial deposition and transport in the environment. PMID:26436254

  19. Solid Surface Combustion at Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Altenkirch, R. A.

    1985-01-01

    The spread of a flame in the gas over the surface of a solid combustible involves in an essential way the transfer of heat from the flame to the solid fuel immediately ahead of it. This heat transfer is affected by the character of the gas phase flame, and so the phenomenon of flame spreading under reduced gravity, in which the flow is generated by gasification of the solid combustible, is apt to be different from what occurs under the Earth's normal gravitational acceleration where the flow is largely buoyancy driven. An experiment is being designed for the Middeck of the Space Shuttle to aid us in understanding the process of flame spreading in the absence of a buoyancy driven flow. A chamber approximately 0.35 cu.m. in volume is to contain either a thin sample of a cellulosic material or a thick sample of polymethyl-methacrylate and an oxidizing environment of O2 and N2. Samples will be ignited at one end, and the ensuing flame spread will be filmed. The spread rate can be determined from the films, and surface and gas-phase temperatures just above the surface will also be recorded. These data will help to clarify the mechanism of forward heat transfer in the low gravity flames.

  20. Aerobic Exercise Program Reduces Anger Expression Among Overweight Children

    PubMed Central

    Tkacz, Joseph; Young-Hyman, Deborah; Boyle, Colleen A.; Davis, Catherine L.

    2009-01-01

    This study tested the effect of a structured aerobic exercise program on anger expression in healthy overweight children. Overweight, sedentary children were randomly assigned to an aerobic exercise program or a no-exercise control condition. All children completed the Pediatric Anger Expression Scale at baseline and posttest. Anger Out and Anger Expression scores were lower for the exercise condition at posttest. Fitness improvements contributed significantly to final models, and points earned for adherence correlated negatively with posttest Anger Out. An aerobic exercise program might be an effective strategy to reduce anger expression, including reduction of aggressive behavior, in overweight children. PMID:19168916

  1. Nanotexturing of surfaces to reduce melting point.

    SciTech Connect

    Garcia, Ernest J.; Zubia, David; Mireles, Jose; Marquez, Noel; Quinones, Stella

    2011-11-01

    This investigation examined the use of nano-patterned structures on Silicon-on-Insulator (SOI) material to reduce the bulk material melting point (1414 C). It has been found that sharp-tipped and other similar structures have a propensity to move to the lower energy states of spherical structures and as a result exhibit lower melting points than the bulk material. Such a reduction of the melting point would offer a number of interesting opportunities for bonding in microsystems packaging applications. Nano patterning process capabilities were developed to create the required structures for the investigation. One of the technical challenges of the project was understanding and creating the specialized conditions required to observe the melting and reshaping phenomena. Through systematic experimentation and review of the literature these conditions were determined and used to conduct phase change experiments. Melting temperatures as low as 1030 C were observed.

  2. Emotional facial expressions reduce neural adaptation to face identity.

    PubMed

    Gerlicher, Anna M V; van Loon, Anouk M; Scholte, H Steven; Lamme, Victor A F; van der Leij, Andries R

    2014-05-01

    In human social interactions, facial emotional expressions are a crucial source of information. Repeatedly presented information typically leads to an adaptation of neural responses. However, processing seems sustained with emotional facial expressions. Therefore, we tested whether sustained processing of emotional expressions, especially threat-related expressions, would attenuate neural adaptation. Neutral and emotional expressions (happy, mixed and fearful) of same and different identity were presented at 3 Hz. We used electroencephalography to record the evoked steady-state visual potentials (ssVEP) and tested to what extent the ssVEP amplitude adapts to the same when compared with different face identities. We found adaptation to the identity of a neutral face. However, for emotional faces, adaptation was reduced, decreasing linearly with negative valence, with the least adaptation to fearful expressions. This short and straightforward method may prove to be a valuable new tool in the study of emotional processing. PMID:23512931

  3. The Arabidopsis Abiotic Stress-Induced TSPO-Related Protein Reduces Cell-Surface Expression of the Aquaporin PIP2;7 through Protein-Protein Interactions and Autophagic Degradation[C][W][OPEN

    PubMed Central

    Hachez, Charles; Veljanovski, Vasko; Reinhardt, Hagen; Guillaumot, Damien; Vanhee, Celine; Chaumont, François

    2014-01-01

    The Arabidopsis thaliana multi-stress regulator TSPO is transiently induced by abiotic stresses. The final destination of this polytopic membrane protein is the Golgi apparatus, where its accumulation is strictly regulated, and TSPO is downregulated through a selective autophagic pathway. TSPO-related proteins regulate the physiology of the cell by generating functional protein complexes. A split-ubiquitin screen for potential TSPO interacting partners uncovered a plasma membrane aquaporin, PIP2;7. Pull-down assays and fluorescence imaging approaches revealed that TSPO physically interacts with PIP2;7 at the endoplasmic reticulum and Golgi membranes in planta. Intriguingly, constitutive expression of fluorescently tagged PIP2;7 in TSPO-overexpressing transgenic lines resulted in patchy distribution of the fluorescence, reminiscent of the pattern of constitutively expressed yellow fluorescent protein-TSPO in Arabidopsis. Mutational stabilization of TSPO or pharmacological inhibition of the autophagic pathway affected concomitantly the detected levels of PIP2;7, suggesting that the complex containing both proteins is degraded through the autophagic pathway. Coexpression of TSPO and PIP2;7 resulted in decreased levels of PIP2;7 in the plasma membrane and abolished the membrane water permeability mediated by transgenic PIP2;7. Taken together, these data support a physiological role for TSPO in regulating the cell-surface expression of PIP2;7 during abiotic stress conditions through protein-protein interaction and demonstrate an aquaporin regulatory mechanism involving TSPO. PMID:25538184

  4. Reducing Sliding Friction with Liquid-Impregnated Surfaces

    NASA Astrophysics Data System (ADS)

    Habibi, Mohammad; Collier, C. Patrick; Boreyko, Jonathan; Nature Inspired Fluids; Interfaces Team; CenterNanophase Materials Sciences Team

    2015-11-01

    Liquid-impregnated surfaces are fabricated by infusing a lubricating liquid into the micro/nano roughness of a textured substrate, such that the surface is slippery for any deposited liquid immiscible with the lubricant. To date, liquid-impregnated surfaces have almost exclusively focused on repelling liquids by minimizing the contact angle hysteresis. Here, we demonstrate that liquid-impregnated surfaces are also capable of reducing sliding friction for solid objects. Ordered arrays of silicon micropillars were infused with lubricating liquids varying in viscosity by two orders of magnitude. Five test surfaces were used: two different micropillared surfaces with and without liquid infusion and a smooth, dry control surface. The static and kinetic coefficients of friction were measured using a polished aluminum cube as the sliding object. Compared to the smooth control surface, the sliding friction was reduced by at least a factor of two on the liquid-impregnated surfaces.

  5. Hemodynamic aspects of reduced platelet adhesion on bioinspired microstructured surfaces.

    PubMed

    Pham, Tam Thanh; Wiedemeier, Stefan; Maenz, Stefan; Gastrock, Gunter; Settmacher, Utz; Jandt, Klaus D; Zanow, Jürgen; Lüdecke, Claudia; Bossert, Jörg

    2016-09-01

    Occlusion by thrombosis due to the absence of the endothelial cell layer is one of the most frequent causes of failure of artificial vascular grafts. Bioinspired surface structures may have a potential to reduce the adhesion of platelets contributing to hemostasis. The aim of this study was to investigate the hemodynamic aspects of platelet adhesion, the main cause of thrombosis, on bioinspired microstructured surfaces mimicking the endothelial cell morphology. We tested the hypothesis that platelet adhesion is statistically significantly reduced on bioinspired microstructured surfaces compared to unstructured surfaces. Platelet adhesion as a function of the microstructure dimensions was investigated under flow conditions on polydimethylsiloxane (PDMS) surfaces by a combined experimental and theoretical approach. Platelet adhesion was statistically significantly reduced (by up to 78%; p≤0.05) on the microstructured PDMS surfaces compared to that on the unstructured control surface. Finite element method (FEM) simulations of blood flow dynamic revealed a micro shear gradient on the microstructure surfaces which plays a pivotal role in reducing platelet adhesion. On the surfaces with the highest differences of the shear stress between the top of the microstructures and the ground areas, platelet adhesion was reduced most. In addition, the microstructures help to reduce the interaction strength between fluid and surfaces, resulting in a larger water contact angle but no higher resistance to flow compared to the unstructured surface. These findings provide new insight into the fundamental mechanisms of reducing platelet adhesion on microstructured bioinspired surfaces and may lay the basis for the development of innovative next generation artificial vascular grafts with reduced risk of thrombosis. PMID:27239904

  6. Possible rainfall reduction through reduced surface temperatures due to overgrazing

    NASA Technical Reports Server (NTRS)

    Otterman, J.

    1975-01-01

    Surface temperature reduction in terrain denuded of vegetation (as by overgrazing) is postulated to decrease air convection, reducing cloudiness and rainfall probability during weak meteorological disturbances. By reducing land-sea daytime temperature differences, the surface temperature reduction decreases daytime circulation of thermally driven local winds. The described desertification mechanism, even when limited to arid regions, high albedo soils, and weak meteorological disturbances, can be an effective rainfall reducing process in many areas including most of the Mediterranean lands.

  7. Development of antifouling surfaces to reduce bacterial attachment

    NASA Astrophysics Data System (ADS)

    Graham, Mary Viola

    Bacteria are exceptionally good at adhering to surfaces and forming complex structures known as biofilms. This process, known as biofouling, can cause problems for infrastructure (eg, clogging and damaging pipes), for the food industry (eg, contamination of processing surfaces and equipment, and for the medical industry (eg, contamination of indwelling medical devices). Accordingly, multiple strategies have been explored to combat biofouling, including chemical modification of surfaces, development of antibiotic coatings, and more recently, the use of engineered surface topography. When designed properly, engineered surface topographies can significantly reduce bacterial surface attachment, ultimately limiting surface colonization. In this work, we hypothesized that the morphology, size, spacing, and surface pre-treatment of topographical features should directly correlate with the size and shape of target organisms, in order to reduce biofouling. Topographical features with size and spacing from 0.25 to 2 mum were fabricated in silicone elastomer and tested against rod shaped bacteria with an average size of 0.5 x 2 mum and spherical bacteria (cocci) ranging from 0.5 - 1 μm in diameter. Antifouling properties of the different topographical features were tested in both static and flow-based assays, and under oxygen plasma-treated (hydrophilic) and untreated (hydrophobic) surface conditions. We found that surface pre-treatment universally affects the ability bacteria to attach to surfaces, while surface topography limits attachment in a manner dependent on the bacterial size/shape and the size/spacing of the topography.

  8. Reduced Ang2 expression in aging endothelial cells.

    PubMed

    Hohensinner, P J; Ebenbauer, B; Kaun, C; Maurer, G; Huber, K; Wojta, J

    2016-06-01

    Aging endothelial cells are characterized by increased cell size, reduced telomere length and increased expression of proinflammatory cytokines. In addition, we describe here that aging reduces the migratory distance of endothelial cells. Furthermore, we observe an increase of the quiescence protein Ang1 and a decrease of the endothelial activation protein Ang2 upon aging. Supplementing Ang2 to aged endothelial cells restored their migratory capacity. We conclude that aging shifts the balance of the Ang1/Ang2 network favouring a quiescent state. Activation of endothelial cells in aging might be necessary to enhance wound healing capacities. PMID:27137842

  9. Surface expression of the Chicxulub crater

    NASA Astrophysics Data System (ADS)

    Pope, Kevin O.; Ocampo, Adriana C.; Kinsland, Gary L.; Smith, Randy

    1996-06-01

    Analyses of geomorphic, soil, and topographic data from the northern Yucatán Peninsula, México, confirm that the buried Chicxulub impact crater has a distinct surface expression and that carbonate sedimentation throughout the Cenozoic has been influenced by the crater. Late Tertiary sedimentation was mostly restricted to the region within the buried crater, and a semicircular moat existed until at least Pliocene time. The topographic expression of the crater is a series of features concentric with the crater. The most prominent is an ˜ 83-km-radius trough or moat containing sinkholes (the Cenote ring). Early Tertiary surfaces rise abruptly outside the moat and form a stepped topography with an outer trough and ridge crest at radii of ˜103 and ˜ 129 km, respectively. Two discontinuous troughs lie within the moat at radii of ˜ 41 and ˜ 62 km. The low ridge between the inner troughs corresponds to the buried peak ring. The moat corresponds to the outer edge of the crater floor demarcated by a major ring fault. The outer trough and the ˜ 62-km-radius inner trough also mark buried ring faults. The ridge crest corresponds to the topographic rim of the crater as modified by postimpact processes. These interpretations support previous findings that the principal impact basin has a diameter of ˜ 180 km, but concentric, low-relief slumping extends well beyond this diameter and the eroded crater rim may extend to a diameter of ˜ 260 km.

  10. Surface expression of the Chicxulub crater

    PubMed

    Pope, K O; Ocampo, A C; Kinsland, G L; Smith, R

    1996-06-01

    Analyses of geomorphic, soil, and topographic data from the northern Yucatan Peninsula, Mexico, confirm that the buried Chicxulub impact crater has a distinct surface expression and that carbonate sedimentation throughout the Cenozoic has been influenced by the crater. Late Tertiary sedimentation was mostly restricted to the region within the buried crater, and a semicircular moat existed until at least Pliocene time. The topographic expression of the crater is a series of features concentric with the crater. The most prominent is an approximately 83-km-radius trough or moat containing sinkholes (the Cenote ring). Early Tertiary surfaces rise abruptly outside the moat and form a stepped topography with an outer trough and ridge crest at radii of approximately 103 and approximately 129 km, respectively. Two discontinuous troughs lie within the moat at radii of approximately 41 and approximately 62 km. The low ridge between the inner troughs corresponds to the buried peak ring. The moat corresponds to the outer edge of the crater floor demarcated by a major ring fault. The outer trough and the approximately 62-km-radius inner trough also mark buried ring faults. The ridge crest corresponds to the topographic rim of the crater as modified by postimpact processes. These interpretations support previous findings that the principal impact basin has a diameter of approximately 180 km, but concentric, low-relief slumping extends well beyond this diameter and the eroded crater rim may extend to a diameter of approximately 260 km. PMID:11539331

  11. Surface seals reduce 1,3-dichloropropene and chloropicrin emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reducing emissions is essential for minimizing the detrimental impact of soil fumigation and for maintaining the availability of fumigants to agricultural uses. This study determined the effectiveness of surface water applications to reduce emissions of 1,3-dichloropropene (1,3-D) and chloropicrin ...

  12. Triptolide reduces the viability of osteosarcoma cells by reducing MKP-1 and Hsp70 expression

    PubMed Central

    ZHAO, LEI; JIANG, BO; WANG, DONG; LIU, WEI; ZHANG, HUAWU; LIU, WEISHENG; QIU, ZHEN

    2016-01-01

    Osteosarcoma is the most common type of malignant bone tumor found in adolescents and young adults. The aim of the present study was to determine whether triptolide, a diterpene epoxide extracted from the Tripterygium plant, was able effectively decrease the viability of osteosarcoma cells. The underlying molecular mechanisms are also investigated. The human osteosarcoma cell lines U-2 OS and MG-63 were used in this study. The U-2 OS and MG-63 cells were treated with 0, 5, 10, 25 or 50 nM triptolide. Cells treated with dimethyl sulfoxide only were used as the no drug treatment control. A commercial MTT kit was used to determine the effects of triptolide on cells. Mitogen-activated protein kinase phosphatase-1 (MKP-1) is frequently overexpressed in tumor tissues, possibly related to the failure of a number of chemotherapeutics. Heat shock protein 70 (Hsp70) is a chaperone molecule that is able to increase drug resistance. The protein expression levels of MKP-1 and Hsp70 were determined using western blot analysis. The results indicate that triptolide effectively reduced the viability of the osteosarcoma cells. Furthermore, triptolide was found to effectively reduce MKP-1 expression and Hsp70 levels. Further analysis showed that triptolide reduced MKP-1 mRNA expression in the U-2 OS and MG-63 cells. Triptolide reduced Hsp70 mRNA expression levels in U-2 OS and MG-63 cells. These results suggest that triptolide effectively decreases the viability of osteosarcoma cells. These effects may be associated with the decreased expression of MKP-1 and Hsp70 levels. These results suggest that triptolide may be used in the treatments of osteosarcoma. PMID:27168842

  13. Mars Express radar collects first surface data

    NASA Astrophysics Data System (ADS)

    2005-08-01

    the middle of August, when the night-time portion of the observations will have almost ended. After that, observation priority will be given to other Mars Express instruments that are best suited to operating in daytime, such as the HRSC camera and Omega mapping spectrometer. However, Marsis will continue its surface and ionospheric investigations in daytime, with ionospheric sounding being reserved for more than 20% of all Mars Express orbits, under all possible Sun illumination conditions. In December, the Mars Express orbit pericentre will enter night-time again. By then, the pericentre will have moved closer to the south pole, allowing Marsis to carry out optimal probing of the subsurface once again, this time in the southern hemisphere. Note to editors The first commissioning phase was given over to testing the Marsis electronics and software and the two 20m-long antennas (dipole). The second commissioning phase, lasting about ten days, will be spent calibrating the 7m ‘monopole’ antenna. This antenna is to be used in conjunction with the Marsis dipole to correct any surface roughness effects caused by the radio waves emitted by the dipole and reflected by an irregular surface. The monopole will find its best use during investigations of areas where surface roughness is greater. The Marsis instrument was developed within the framework of a Memorandum of Understanding between the Italian Space Agency (ASI) and NASA. It was developed by Alenia Spazio under ASI management and the scientific supervision of University of Rome ‘La Sapienza’, in partnership with the Jet Propulsion Laboratory (JPL) and the University of Iowa. JPL provided the antenna manufactured by Astro Aerospace. It is the first instrument designed to actually look below the surface of Mars. Its major goals are to characterise the subsurface layers of sediments and possibly detect underground water or ice, conduct large-scale altimetry mapping and provide data on the planet’s ionosphere. For

  14. Surface nanocrystallization of stainless steel for reduced biofilm adherence.

    PubMed

    Yu, Bin; Davis, Elisabeth M; Hodges, Robert S; Irvin, Randall T; Li, D Y

    2008-08-20

    Stainless steel is one of the most common metallic biomedical materials. For medical applications, its resistance to the adherence of biofilms is of importance to the elimination or minimization of bacterial infections. In this study, we demonstrate the effectiveness of a process combining surface nanocrystallization and thermal oxidation (or a recovery heat treatment in air) for reducing the biofilm's adherence to stainless steel. During this treatment, a target surface was sandblasted and the resultant dislocation cells in the surface layer were turned into nanosized grains by a subsequent recovery treatment in air. This process generated a more protective oxide film that blocked the electron exchange or reduced the surface activity more effectively. As a result, the biofilm's adherence to the treated surface was markedly minimized. A synthetic peptide was utilized as a substitute of biofilms to evaluate the adhesion between a treated steel surface and biofilms using an atomic force microscope (AFM) through measuring the adhesive force between the target surface and a peptide-coated AFM tip. It was shown that the adhesive force decreased with a decrease in the grain size of the steel. The corresponding surface electron work function (EWF) of the steel was also measured, which showed a trend of variation in EWF with the grain size, consistent with corresponding changes in the adhesive force. PMID:21730615

  15. Surface nanocrystallization of stainless steel for reduced biofilm adherence

    NASA Astrophysics Data System (ADS)

    Yu, Bin; Davis, Elisabeth M.; Hodges, Robert S.; Irvin, Randall T.; Li, D. Y.

    2008-08-01

    Stainless steel is one of the most common metallic biomedical materials. For medical applications, its resistance to the adherence of biofilms is of importance to the elimination or minimization of bacterial infections. In this study, we demonstrate the effectiveness of a process combining surface nanocrystallization and thermal oxidation (or a recovery heat treatment in air) for reducing the biofilm's adherence to stainless steel. During this treatment, a target surface was sandblasted and the resultant dislocation cells in the surface layer were turned into nanosized grains by a subsequent recovery treatment in air. This process generated a more protective oxide film that blocked the electron exchange or reduced the surface activity more effectively. As a result, the biofilm's adherence to the treated surface was markedly minimized. A synthetic peptide was utilized as a substitute of biofilms to evaluate the adhesion between a treated steel surface and biofilms using an atomic force microscope (AFM) through measuring the adhesive force between the target surface and a peptide-coated AFM tip. It was shown that the adhesive force decreased with a decrease in the grain size of the steel. The corresponding surface electron work function (EWF) of the steel was also measured, which showed a trend of variation in EWF with the grain size, consistent with corresponding changes in the adhesive force.

  16. Zwitteration: Coating Surfaces with Zwitterionic Functionality to Reduce Nonspecific Adsorption

    PubMed Central

    2015-01-01

    Coating surfaces with thin or thick films of zwitterionic material is an effective way to reduce or eliminate nonspecific adsorption to the solid/liquid interface. This review tracks the various approaches to zwitteration, such as monolayer assemblies and polymeric brush coatings, on micro- to macroscopic surfaces. A critical summary of the mechanisms responsible for antifouling shows how zwitterions are ideally suited to this task. PMID:24754399

  17. Reduced Expression of MYC Increases Longevity and Enhances Healthspan

    PubMed Central

    Hofmann, Jeffrey W.; Zhao, Xiaoai; De Cecco, Marco; Peterson, Abigail L.; Pagliaroli, Luca; Manivannan, Jayameenakshi; Hubbard, Gene B.; Ikeno, Yuji; Zhang, Yongqing; Feng, Bin; Li, Xiaxi; Serre, Thomas; Qi, Wenbo; Van Remmen, Holly; Miller, Richard A.; Bath, Kevin G.; de Cabo, Rafael; Xu, Haiyan; Neretti, Nicola; Sedivy, John M.

    2015-01-01

    SUMMARY MYC is a highly pleiotropic transcription factor whose deregulation promotes cancer. In contrast, we find that Myc haploinsufficient (Myc+/−) mice exhibit increased lifespan. They show resistance to several age-associated pathologies, including osteoporosis, cardiac fibrosis and immunosenescence. They also appear to be more active, with a higher metabolic rate and healthier lipid metabolism. Transcriptomic analysis reveals a gene expression signature enriched for metabolic and immune processes. The ancestral role of MYC as a regulator of ribosome biogenesis is reflected in reduced protein translation, which is inversely correlated with longevity. We also observe changes in nutrient and energy sensing pathways, including reduced serum IGF-1, increased AMPK activity, and decreased AKT, TOR and S6K activities. In contrast to observations in other longevity models, Myc+/− mice do not show improvements in stress management pathways. Our findings indicate that MYC activity has a significant impact on longevity and multiple aspects of mammalian healthspan. PMID:25619689

  18. Reduced expression of MYC increases longevity and enhances healthspan.

    PubMed

    Hofmann, Jeffrey W; Zhao, Xiaoai; De Cecco, Marco; Peterson, Abigail L; Pagliaroli, Luca; Manivannan, Jayameenakshi; Hubbard, Gene B; Ikeno, Yuji; Zhang, Yongqing; Feng, Bin; Li, Xiaxi; Serre, Thomas; Qi, Wenbo; Van Remmen, Holly; Miller, Richard A; Bath, Kevin G; de Cabo, Rafael; Xu, Haiyan; Neretti, Nicola; Sedivy, John M

    2015-01-29

    MYC is a highly pleiotropic transcription factor whose deregulation promotes cancer. In contrast, we find that Myc haploinsufficient (Myc(+/-)) mice exhibit increased lifespan. They show resistance to several age-associated pathologies, including osteoporosis, cardiac fibrosis, and immunosenescence. They also appear to be more active, with a higher metabolic rate and healthier lipid metabolism. Transcriptomic analysis reveals a gene expression signature enriched for metabolic and immune processes. The ancestral role of MYC as a regulator of ribosome biogenesis is reflected in reduced protein translation, which is inversely correlated with longevity. We also observe changes in nutrient and energy sensing pathways, including reduced serum IGF-1, increased AMPK activity, and decreased AKT, TOR, and S6K activities. In contrast to observations in other longevity models, Myc(+/-) mice do not show improvements in stress management pathways. Our findings indicate that MYC activity has a significant impact on longevity and multiple aspects of mammalian healthspan. PMID:25619689

  19. Inhibition of TGFBIp expression reduces lymphangiogenesis and tumor metastasis.

    PubMed

    Maeng, Y-S; Aguilar, B; Choi, S-I; Kim, E K

    2016-01-14

    Transforming growth factor-β-induced protein (TGFBIp) is an extracellular matrix protein that has a role in a wide range of pathological conditions. However, the role of TGFBIp signaling in lymphangiogenesis is poorly understood. The purpose of this study was therefore to analyze the effects of TGFBIp on lymphangiogenesis and determine whether TGFBIp-related lymphangiogenesis is important for the metastasis of tumor cells. TGFBIp increased adhesion, migration, and morphologic differentiation of human lymphatic endothelial cells (LECs), consistent with an increase in lymphatic vessel sprouting in a three-dimensional lymphatic ring assay. TGFBIp also induced phosphorylation of intracellular signaling molecules SRC, FAK, AKT, JNK and ERK. TGFBIp-induced lymphatic vessel sprouting was inhibited by addition of anti-integrin β3 antibody and pharmacologic inhibitors of FAK, AKT, JNK or ERK. TGFBIp increased both CCL21 expression in LECs, a chemokine that actively recruits tumor cells expressing the cognate chemokine receptors to lymphatic vessels and LEC permeability by inducing the dissociation of VE-cadherin junctions between LECs via the activation of SRC signaling. In vivo, inhibition of TGFBIp expression in SW620 cancer cells dramatically reduced tumor lymphangiogenesis and metastasis. Collectively, our findings demonstrate that TGFBIp is a lymphangiogenic factor contributing to tumor dissemination and represents a potential target to inhibit metastasis. PMID:25772247

  20. Textured bearing surface in artificial joints to reduce macrophage activation

    NASA Astrophysics Data System (ADS)

    Nakanishi, Yoshitaka; Nishi, Naoki; Chikaura, Hiroto; Nakashima, Yuta; Miura, Hiromasa; Higaki, Hidehiko; Mizuta, Hiroshi; Iwamoto, Yukihide; Fujiwara, Yukio; Komohara, Yoshihiro; Takeya, Motohiro

    2015-12-01

    Micro slurry-jet erosion has been proposed as a precision machining technique for the bearing surfaces of artificial joints in order to reduce the total amount of polyethylene wear and to enlarge the size of the wear debris. The micro slurry-jet erosion method is a wet blasting technique which uses alumina particles as the abrasive medium along with compressed air and water to create an ideal surface. Pin-on-disc wear tests with multidirectional sliding motion on the textured surface of a \\text{Co}-\\text{Cr}-\\text{Mo} alloy counterface for polyethylene resulted in both a reduction of wear as well as enlargement of the polyethylene debris size. In this study, primary human peripheral blood mononuclear phagocytes were incubated with the debris, and it was elucidated that the wear debris generated on the textured surface regulated secretion of the proinflammatory cytokines IL-6 and TNF-α, indicating a reduction in the induced tissue reaction and joint loosening.

  1. Reducing measurement scale mismatch to improve surface energy flux estimation

    NASA Astrophysics Data System (ADS)

    Iwema, Joost; Rosolem, Rafael; Rahman, Mostaquimur; Blyth, Eleanor; Wagener, Thorsten

    2016-04-01

    Soil moisture importantly controls land surface processes such as energy and water partitioning. A good understanding of these controls is needed especially when recognizing the challenges in providing accurate hyper-resolution hydrometeorological simulations at sub-kilometre scales. Soil moisture controlling factors can, however, differ at distinct scales. In addition, some parameters in land surface models are still often prescribed based on observations obtained at another scale not necessarily employed by such models (e.g., soil properties obtained from lab samples used in regional simulations). To minimize such effects, parameters can be constrained with local data from Eddy-Covariance (EC) towers (i.e., latent and sensible heat fluxes) and Point Scale (PS) soil moisture observations (e.g., TDR). However, measurement scales represented by EC and PS still differ substantially. Here we use the fact that Cosmic-Ray Neutron Sensors (CRNS) estimate soil moisture at horizontal footprint similar to that of EC fluxes to help answer the following question: Does reduced observation scale mismatch yield better soil moisture - surface fluxes representation in land surface models? To answer this question we analysed soil moisture and surface fluxes measurements from twelve COSMOS-Ameriflux sites in the USA characterized by distinct climate, soils and vegetation types. We calibrated model parameters of the Joint UK Land Environment Simulator (JULES) against PS and CRNS soil moisture data, respectively. We analysed the improvement in soil moisture estimation compared to uncalibrated model simulations and then evaluated the degree of improvement in surface fluxes before and after calibration experiments. Preliminary results suggest that a more accurate representation of soil moisture dynamics is achieved when calibrating against observed soil moisture and further improvement obtained with CRNS relative to PS. However, our results also suggest that a more accurate

  2. Subinhibitory Concentrations of Linezolid Reduce Staphylococcus aureus Virulence Factor Expression

    PubMed Central

    Bernardo, Katussevani; Pakulat, Norbert; Fleer, Silke; Schnaith, Annabelle; Utermöhlen, Olaf; Krut, Oleg; Müller, Stefan; Krönke, Martin

    2004-01-01

    The influence of the antibiotic linezolid on the secretion of exotoxins by Staphylococcus aureus was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis combined with matrix-assisted laser desorption ionization-time of flight mass spectrometry and Western blot analysis. S. aureus suspensions were treated with grading subinhibitory concentrations of linezolid (12.5, 25, 50, and 90% of MIC) at different stages of bacterial growth (i.e., an optical density at 540 nm [OD540] of 0.05 or 0.8). When added to S. aureus cultures at an OD540 of 0.05, linezolid reduced in a dose-dependent manner the secretion of specific virulence factors, including staphylococcal enterotoxin A (SEA) and SEB, bifunctional autolysin, autolysin, protein A, and alpha- and beta-hemolysins. In contrast, other presumably nontoxic exoproteins remained unchanged or even accumulated in supernatants in the presence of linezolid at a 90% MIC. Similarily, when added at OD540 of 0.8, that is, after quorum sensing, linezolid reduced the release of virulence factors, whereas the relative abundance of nontoxic exoproteins such as triacylglycerol lipase, glycerol ester hydrolase, DnaK, or translation elongation factor EF-Tu was found to be increased. Consistently, linezolid reduced in a dose-dependent manner the tumor necrosis factor-inducing activity secreted by S. aureus into the culture supernatants. The results of our study suggest that the expression of virulence factors in S. aureus is especially sensitive to the inhibition of protein synthesis by linezolid, which should be an advantage in the treatment of infections with toxin-producing S. aureus. PMID:14742208

  3. Reducing extrinsic damping of surface acoustic waves at gigahertz frequencies

    NASA Astrophysics Data System (ADS)

    Gelda, Dhruv; Sadhu, Jyothi; Ghossoub, Marc G.; Ertekin, Elif; Sinha, Sanjiv

    2016-04-01

    High-frequency surface acoustic waves (SAWs) in the gigahertz range can be generated using absorption from an ultrafast laser in a patterned metallic grating on a substrate. Reducing the attenuation at these frequencies can yield better sensors as well as enable them to better probe phonon and electron-phonon interactions near surfaces. It is not clear from existing experiments which mechanisms dominate damping at high frequencies. We calculate damping times of SAWs due to various mechanisms in the 1-100 GHz range to find that mechanical loading of the grating on the substrate dominates dissipation by radiating energy from the surface into the bulk. To overcome this and enable future measurements to probe intrinsic damping, we propose incorporating distributed acoustic Bragg reflectors in the experimental structure. Layers of alternating materials with contrasting acoustic impedances embedded a wavelength away from the surface serve to reflect energy back to the surface. Using numerical simulations, we show that a single Bragg reflector is sufficient to increase the energy density at the surface by more than five times. We quantify the resulting damping time to find that it is longer than the intrinsic damping time. The proposed structure can enable future measurements of intrinsic damping in SAWs at ˜100 GHz.

  4. Glioma cell proliferation controlled by ERK activity-dependent surface expression of PDGFRA.

    PubMed

    Chen, Dongfeng; Zuo, Duo; Luan, Cheng; Liu, Min; Na, Manli; Ran, Liang; Sun, Yingyu; Persson, Annette; Englund, Elisabet; Salford, Leif G; Renström, Erik; Fan, Xiaolong; Zhang, Enming

    2014-01-01

    Increased PDGFRA signaling is an essential pathogenic factor in many subtypes of gliomas. In this context the cell surface expression of PDGFRA is an important determinant of ligand sensing in the glioma microenvironment. However, the regulation of spatial distribution of PDGFRA in glioma cells remains poorly characterized. Here, we report that cell surface PDGFRA expression in gliomas is negatively regulated by an ERK-dependent mechanism, resulting in reduced proliferation of glioma cells. Glioma tumor tissues and their corresponding cell lines were isolated from 14 patients and analyzed by single-cell imaging and flow cytometry. In both cell lines and their corresponding tumor samples, glioma cell proliferation correlated with the extent of surface expression of PDGFRA. High levels of surface PDGFRA also correlated to high tubulin expression in glioma tumor tissue in vivo. In glioma cell lines, surface PDGFRA declined following treatment with inhibitors of tubulin, actin and dynamin. Screening of a panel of small molecule compounds identified the MEK inhibitor U0126 as a potent inhibitor of surface PDGFRA expression. Importantly, U0126 inhibited surface expression in a reversible, dose- and time-dependent manner, without affecting general PDGFRA expression. Treatment with U0126 resulted in reduced co-localization between PDGFRA and intracellular trafficking molecules e.g. clathrin, RAB11 and early endosomal antigen-1, in parallel with enhanced co-localization between PDGFRA and the Golgi cisternae maker, Giantin, suggesting a deviation of PDGFRA from the endosomal trafficking and recycling compartment, to the Golgi network. Furthermore, U0126 treatment in glioma cells induced an initial inhibition of ERK1/2 phosphorylation, followed by up-regulated ERK1/2 phosphorylation concomitant with diminished surface expression of PDGFRA. Finally, down-regulation of surface PDGFRA expression by U0126 is concordant with reduced glioma cell proliferation. These findings

  5. Multiscale Topographical Analysis of Biogeochemically Reduced Hematite Surfaces

    NASA Astrophysics Data System (ADS)

    Rustad, J.; Rosso, K. M.; Dubuffet, F.; Yuen, D. A.

    2001-12-01

    Establishing the mechanisms and magnitudes of nano-mesoscale influences on interfacial chemical reactivity requires a multiscale description of the structure of the interfacial region. The identification of scaling relationships characterizing mineral surface structure in low-temperature environments is a first step in the construction structure-activity relationships that are potentially applicable over multiple length scales. Using wavelet image processing techniques and scaling relationships such as the evaluation of Hurst exponents and fractal dimension, we systematize and quantify mineral surface topography of a sample of hematite undergoing biochemically induced reductive dissolution. Image mosaicking methods commonly applied in remote sensing and medical imaging contexts are applied to AFM images to obtain large scale images for the evalution of scaling exponents. Gaussian wavelet methods are used to enhance and quantify structural features associated with the biogeochemically reduced surfaces.

  6. Polyelectrolytes Ability in Reducing Atrazine Concentration in Water: Surface Effects

    PubMed Central

    Heijman, S. G. J.; Lopes, S. I. C.; Rietveld, L. C.

    2014-01-01

    This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with a 1 kDa membrane. The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments. In the beginning, the theoretical L-type of the isotherm of Giles' classification was expected with an increase in the dosage of the polymer. However, in this study, the conventional type of isotherm was not observed. It was found that the adsorption of the cationic polymer on the negatively charged glass surface was necessary and influential for the removal of atrazine. Surface-to-volume ratio adsorption experiments were performed to elucidate the mechanisms and the polymer configuration. The glass surface area was determined to be a limiting parameter in the adsorption mechanism. PMID:25197693

  7. Polyelectrolytes ability in reducing atrazine concentration in water: surface effects.

    PubMed

    Mohd Amin, Mohamad Faiz; Heijman, S G J; Lopes, S I C; Rietveld, L C

    2014-01-01

    This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with a 1 kDa membrane. The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments. In the beginning, the theoretical L-type of the isotherm of Giles' classification was expected with an increase in the dosage of the polymer. However, in this study, the conventional type of isotherm was not observed. It was found that the adsorption of the cationic polymer on the negatively charged glass surface was necessary and influential for the removal of atrazine. Surface-to-volume ratio adsorption experiments were performed to elucidate the mechanisms and the polymer configuration. The glass surface area was determined to be a limiting parameter in the adsorption mechanism. PMID:25197693

  8. Reducing Surface Clutter in Cloud Profiling Radar Data

    NASA Technical Reports Server (NTRS)

    Tanelli, Simone; Pak, Kyung; Durden, Stephen; Im, Eastwood

    2008-01-01

    An algorithm has been devised to reduce ground clutter in the data products of the CloudSat Cloud Profiling Radar (CPR), which is a nadir-looking radar instrument, in orbit around the Earth, that measures power backscattered by clouds as a function of distance from the instrument. Ground clutter contaminates the CPR data in the lowest 1 km of the atmospheric profile, heretofore making it impossible to use CPR data to satisfy the scientific interest in studying clouds and light rainfall at low altitude. The algorithm is based partly on the fact that the CloudSat orbit is such that the geodetic altitude of the CPR varies continuously over a range of approximately 25 km. As the geodetic altitude changes, the radar timing parameters are changed at intervals defined by flight software in order to keep the troposphere inside a data-collection time window. However, within each interval, the surface of the Earth continuously "scans through" (that is, it moves across) a few range bins of the data time window. For each radar profile, only few samples [one for every range-bin increment ((Delta)r = 240 m)] of the surface-clutter signature are available around the range bin in which the peak of surface return is observed, but samples in consecutive radar profiles are offset slightly (by amounts much less than (Delta)r) with respect to each other according to the relative change in geodetic altitude. As a consequence, in a case in which the surface area under examination is homogenous (e.g., an ocean surface), a sequence of consecutive radar profiles of the surface in that area contains samples of the surface response with range resolution (Delta)p much finer than the range-bin increment ((Delta)p << r). Once the high-resolution surface response has thus become available, the profile of surface clutter can be accurately estimated by use of a conventional maximum-correlation scheme: A translated and scaled version of the high-resolution surface response is fitted to the observed

  9. Reducing ZnO nanoparticle cytotoxicity by surface modification

    NASA Astrophysics Data System (ADS)

    Luo, Mingdeng; Shen, Cenchao; Feltis, Bryce N.; Martin, Lisandra L.; Hughes, Anthony E.; Wright, Paul F. A.; Turney, Terence W.

    2014-05-01

    Nanoparticulate zinc oxide (ZnO) is one of the most widely used engineered nanomaterials and its toxicology has gained considerable recent attention. A key aspect for controlling biological interactions at the nanoscale is understanding the relevant nanoparticle surface chemistry. In this study, we have determined the disposition of ZnO nanoparticles within human immune cells by measurement of total Zn, as well as the proportions of extra- and intracellular dissolved Zn as a function of dose and surface coating. From this mass balance, the intracellular soluble Zn levels showed little difference in regard to dose above a certain minimal level or to different surface coatings. PEGylation of ZnO NPs reduced their cytotoxicity as a result of decreased cellular uptake arising from a minimal protein corona. We conclude that the key role of the surface properties of ZnO NPs in controlling cytotoxicity is to regulate cellular nanoparticle uptake rather than altering either intracellular or extracellular Zn dissolution.Nanoparticulate zinc oxide (ZnO) is one of the most widely used engineered nanomaterials and its toxicology has gained considerable recent attention. A key aspect for controlling biological interactions at the nanoscale is understanding the relevant nanoparticle surface chemistry. In this study, we have determined the disposition of ZnO nanoparticles within human immune cells by measurement of total Zn, as well as the proportions of extra- and intracellular dissolved Zn as a function of dose and surface coating. From this mass balance, the intracellular soluble Zn levels showed little difference in regard to dose above a certain minimal level or to different surface coatings. PEGylation of ZnO NPs reduced their cytotoxicity as a result of decreased cellular uptake arising from a minimal protein corona. We conclude that the key role of the surface properties of ZnO NPs in controlling cytotoxicity is to regulate cellular nanoparticle uptake rather than

  10. Calreticulin: Roles in Cell-Surface Protein Expression

    PubMed Central

    Jiang, Yue; Dey, Sandeepa; Matsunami, Hiroaki

    2014-01-01

    In order to perform their designated functions, proteins require precise subcellular localizations. For cell-surface proteins, such as receptors and channels, they are able to transduce signals only when properly targeted to the cell membrane. Calreticulin is a multi-functional chaperone protein involved in protein folding, maturation, and trafficking. However, evidence has been accumulating that calreticulin can also negatively regulate the surface expression of certain receptors and channels. In these instances, depletion of calreticulin enhances cell-surface expression and function. In this review, we discuss the role of calreticulin with a focus on its negative effects on the expression of cell-surface proteins. PMID:25230046

  11. Dimethylmercury Formation Mediated by Inorganic and Organic Reduced Sulfur Surfaces

    NASA Astrophysics Data System (ADS)

    Jonsson, Sofi; Mazrui, Nashaat M.; Mason, Robert P.

    2016-06-01

    Underlying formation pathways of dimethylmercury ((CH3)2Hg) in the ocean are unknown. Early work proposed reactions of inorganic Hg (HgII) with methyl cobalamin or of dissolved monomethylmercury (CH3Hg) with hydrogen sulfide as possible bacterial mediated or abiotic pathways. A significant fraction (up to 90%) of CH3Hg in natural waters is however adsorbed to reduced sulfur groups on mineral or organic surfaces. We show that binding of CH3Hg to such reactive sites facilitates the formation of (CH3)2Hg by degradation of the adsorbed CH3Hg. We demonstrate that the reaction can be mediated by different sulfide minerals, as well as by dithiols suggesting that e.g. reduced sulfur groups on mineral particles or on protein surfaces could mediate the reaction. The observed fraction of CH3Hg methylated on sulfide mineral surfaces exceeded previously observed methylation rates of CH3Hg to (CH3)2Hg in seawaters and we suggest the pathway demonstrated here could account for much of the (CH3)2Hg found in the ocean.

  12. Dimethylmercury Formation Mediated by Inorganic and Organic Reduced Sulfur Surfaces

    PubMed Central

    Jonsson, Sofi; Mazrui, Nashaat M.; Mason, Robert P.

    2016-01-01

    Underlying formation pathways of dimethylmercury ((CH3)2Hg) in the ocean are unknown. Early work proposed reactions of inorganic Hg (HgII) with methyl cobalamin or of dissolved monomethylmercury (CH3Hg) with hydrogen sulfide as possible bacterial mediated or abiotic pathways. A significant fraction (up to 90%) of CH3Hg in natural waters is however adsorbed to reduced sulfur groups on mineral or organic surfaces. We show that binding of CH3Hg to such reactive sites facilitates the formation of (CH3)2Hg by degradation of the adsorbed CH3Hg. We demonstrate that the reaction can be mediated by different sulfide minerals, as well as by dithiols suggesting that e.g. reduced sulfur groups on mineral particles or on protein surfaces could mediate the reaction. The observed fraction of CH3Hg methylated on sulfide mineral surfaces exceeded previously observed methylation rates of CH3Hg to (CH3)2Hg in seawaters and we suggest the pathway demonstrated here could account for much of the (CH3)2Hg found in the ocean. PMID:27302323

  13. HLA reduces KIR expression level and frequency in a humanized mouse model1

    PubMed Central

    van Bergen, Jeroen; Thompson, Allan; Retière, Christelle; van Pel, Melissa; Salvatori, Daniela; Lemonnier, François; Raulet, David; Trowsdale, John; Koning, Frits

    2014-01-01

    Many human Natural Killer (NK) cells are prevented from killing autologous cells by virtue of inhibitory Killer cell Immunoglobulin-like Receptors (KIR) binding `self' HLA class I molecules. Individual NK cells stably express a selected set of KIR, but it is currently disputed whether the fraction of NK cells expressing a particular inhibitory KIR is influenced by the presence of the corresponding HLA ligand. This issue has been particularly hard to tackle in a statistically meaningful way due to the extreme polymorphism of the KIR and HLA loci, with widely varying affinities for individual KIR and HLA allele combinations. Here, we use a transgenic mouse model to investigate the effect of HLA on KIR repertoire and function. In this model system, a functional interaction between HLA-Cw3 and KIR2DL2 reduced both the surface expression of KIR2DL2 as well as the frequency of KIR2DL2+ cells. PMID:23390293

  14. Modulated surface nanostructures for enhanced light trapping and reduced surface reflection of crystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Tayagaki, Takeshi; Hoshi, Yusuke; Hirai, Yuji; Matsuo, Yasutaka; Usami, Noritaka

    2016-05-01

    We demonstrated the fabrication of modulated surface nanostructures as a new surface texture design for thin wafer solar cells. Using a combination of conventional alkali etching and colloidal lithography, we fabricated surface textures with micrometer and nanometre scales on a Si substrate. These modulated surface nanostructures exhibit reduced surface reflection in a broad spectral range, compared with conventional micrometer textures. We investigated optical absorption using a rigorous coupled wave analysis simulation, which revealed a significant reduction in surface reflection over a broad spectral range and efficient light trapping (comparable to that of conventional micrometer-scale textures) for the modulated nanostructures. We found that the modulated surface nanostructures have a high potential of improving the performance of thin wafer crystalline Si solar cells.

  15. Thrombospondin-4 reduces binding affinity of [(3)H]-gabapentin to calcium-channel α2δ-1-subunit but does not interact with α2δ-1 on the cell-surface when co-expressed.

    PubMed

    Lana, Beatrice; Page, Karen M; Kadurin, Ivan; Ho, Shuxian; Nieto-Rostro, Manuela; Dolphin, Annette C

    2016-01-01

    The α2δ proteins are auxiliary subunits of voltage-gated calcium channels, and influence their trafficking and biophysical properties. The α2δ ligand gabapentin interacts with α2δ-1, and inhibits calcium channel trafficking. However, α2-1 has also been proposed to play a synaptogenic role, independent of calcium channel function. In this regard, α2δ-1 was identified as a ligand of thrombospondins, with the interaction involving the thrombospondin synaptogenic domain and the α2δ-1 von-Willebrand-factor domain. Co-immunoprecipitation between α2δ-1 and the synaptogenic domain of thrombospondin-2 was prevented by gabapentin. We therefore examined whether interaction of thrombospondin with α2δ-1 might reciprocally influence (3)H-gabapentin binding. We concentrated on thrombospondin-4, because, like α2δ-1, it is upregulated in neuropathic pain models. We found that in membranes from cells co-transfected with α2δ-1 and thrombospondin-4, there was a Mg(2+) -dependent reduction in affinity of (3)H-gabapentin binding to α2δ-1. This effect was lost for α2δ-1 with mutations in the von-Willebrand-factor-A domain. However, the effect on (3)H-gabapentin binding was not reproduced by the synaptogenic EGF-domain of thrombospondin-4. Partial co-immunoprecipitation could be demonstrated between thrombospondin-4 and α2δ-1 when co-transfected, but there was no co-immunoprecipitation with thrombospondin-4-EGF domain. Furthermore, we could not detect any association between these two proteins on the cell-surface, indicating the demonstrated interaction occurs intracellularly. PMID:27076051

  16. Thrombospondin-4 reduces binding affinity of [3H]-gabapentin to calcium-channel α2δ-1-subunit but does not interact with α2δ-1 on the cell-surface when co-expressed

    PubMed Central

    Lana, Beatrice; Page, Karen M.; Kadurin, Ivan; Ho, Shuxian; Nieto-Rostro, Manuela; Dolphin, Annette C.

    2016-01-01

    The α2δ proteins are auxiliary subunits of voltage-gated calcium channels, and influence their trafficking and biophysical properties. The α2δ ligand gabapentin interacts with α2δ-1, and inhibits calcium channel trafficking. However, α2-1 has also been proposed to play a synaptogenic role, independent of calcium channel function. In this regard, α2δ-1 was identified as a ligand of thrombospondins, with the interaction involving the thrombospondin synaptogenic domain and the α2δ-1 von-Willebrand-factor domain. Co-immunoprecipitation between α2δ-1 and the synaptogenic domain of thrombospondin-2 was prevented by gabapentin. We therefore examined whether interaction of thrombospondin with α2δ-1 might reciprocally influence 3H-gabapentin binding. We concentrated on thrombospondin-4, because, like α2δ-1, it is upregulated in neuropathic pain models. We found that in membranes from cells co-transfected with α2δ-1 and thrombospondin-4, there was a Mg2+ -dependent reduction in affinity of 3H-gabapentin binding to α2δ-1. This effect was lost for α2δ-1 with mutations in the von-Willebrand-factor-A domain. However, the effect on 3H-gabapentin binding was not reproduced by the synaptogenic EGF-domain of thrombospondin-4. Partial co-immunoprecipitation could be demonstrated between thrombospondin-4 and α2δ-1 when co-transfected, but there was no co-immunoprecipitation with thrombospondin-4-EGF domain. Furthermore, we could not detect any association between these two proteins on the cell-surface, indicating the demonstrated interaction occurs intracellularly. PMID:27076051

  17. Containment of a silicone fluid free surface in reduced gravity

    NASA Technical Reports Server (NTRS)

    Pline, A.; Jacobson, T.

    1988-01-01

    In support of the surface tension driven convection experiment planned for flight aboard the Space Shuttle, tests were conducted under reduced gravity in the 2.2-sec drop tower and the 5.0-sec Zero-G facility at the Lewis Research Center. The dynamics of controlling the test fluid, a 10-centistoke viscosity silicone fluid, in a low-gravity environment were investigated using different container designs and barrier coatings. Three container edge designs were tested without a barrier coating: a square edge, a sharp edge with a 45-deg slope, and a saw-tooth edge. All three edge designs were successful in containing the fluid below the edge.

  18. Reducing the Surface Degradation of Aluminum Extrusion Dies During Preheating

    NASA Astrophysics Data System (ADS)

    Stratton, Paul

    2010-07-01

    Aluminum extrusion dies are usually made from H13 steel that is ferritically nitrocarburized to minimize wear and pick-up. Before being placed in the extrusion press, the dies are preheated to minimize thermal shock at the start of the extrusion cycle. During the preheating time, the nitrocarburized layer oxidizes. Some of this layer can break away during extrusion leaving marks on the product. Although inerting the preheat furnaces with nitrogen has been found to reduce the oxidation, it does not solve the problem completely. Experiments have shown that a small addition of ammonia to the preheating protective atmosphere could eliminate oxidation and prevent nitrogen loss from the surface nitride layer.

  19. Arterial Shear Stress Reduces Eph-B4 Expression in Adult Human Veins

    PubMed Central

    Model, Lynn S.; Hall, Michael R.; Wong, Daniel J.; Muto, Akihito; Kondo, Yuka; Ziegler, Kenneth R.; Feigel, Amanda; Quint, Clay; Niklason, Laura; Dardik, Alan

    2014-01-01

    Vein graft adaptation to the arterial environment is characterized by loss of venous identity, with reduced Ephrin type-B receptor 4 (Eph-B4) expression but without increased Ephrin-B2 expression. We examined changes of vessel identity of human saphenous veins in a flow circuit in which shear stress could be precisely controlled. Medium circulated at arterial or venous magnitudes of laminar shear stress for 24 hours; histologic, protein, and RNA analyses of vein segments were performed. Vein endothelium remained viable and functional, with platelet endothelial cell adhesion molecule (PECAM)-expressing cells on the luminal surface. Venous Eph-B4 expression diminished (p = .002), Ephrin-B2 expression was not induced (p = .268), and expression of osteopontin (p = .002) was increased with exposure to arterial magnitudes of shear stress. Similar changes were not found in veins placed under venous flow or static conditions. These data show that human saphenous veins remain viable during ex vivo application of shear stress in a bioreactor, without loss of the venous endothelium. Arterial magnitudes of shear stress cause loss of venous identity without gain of arterial identity in human veins perfused ex vivo. Shear stress alone, without immunologic or hormonal influence, is capable of inducing changes in vessel identity and, specifically, loss of venous identity. PMID:25191151

  20. Surface expression of ω-transaminase in Escherichia coli.

    PubMed

    Gustavsson, Martin; Muraleedharan, Madhu Nair; Larsson, Gen

    2014-04-01

    Chiral amines are important for the chemical and pharmaceutical industries, and there is rapidly growing interest to use transaminases for their synthesis. Since the cost of the enzyme is an important factor for process economy, the use of whole-cell biocatalysts is attractive, since expensive purification and immobilization steps can be avoided. Display of the protein on the cell surface provides a possible way to reduce the mass transfer limitations of such biocatalysts. However, transaminases need to dimerize in order to become active, and furthermore, they require the cofactor pyridoxal phosphate; consequently, successful transaminase surface expression has not been reported thus far. In this work, we produced an Arthrobacter citreus ω-transaminase in Escherichia coli using a surface display vector based on the autotransporter adhesin involved in diffuse adherence (AIDA-I), which has previously been used for display of dimeric proteins. The correct localization of the transaminase in the E. coli outer membrane and its orientation toward the cell exterior were verified. Furthermore, transaminase activity was detected exclusively in the outer membrane protein fraction, showing that successful dimerization had occurred. The transaminase was found to be present in both full-length and proteolytically degraded forms. The removal of this proteolysis is considered to be the main obstacle to achieving sufficient whole-cell transaminase activity. PMID:24487538

  1. Reducing crude protein in beef cattle diet reduces ammonia emissions from artificial feedyard surfaces.

    PubMed

    Todd, Richard W; Cole, N Andy; Clark, R Nolan

    2006-01-01

    Concentrated animal feeding operations are major sources of ammonia to the atmosphere. Control methods to reduce emissions include acidifying amendments, urease inhibitors, and absorbents. For beef cattle, decreasing crude protein (CP) in diets may be the most practical and cost-effective method to reduce ammonia emissions. Our objective was to quantify the effect of reducing CP in beef cattle diet on ammonia emissions. Two groups of steers were fed diets with either 11.5 or 13.0% CP and all urine and feces were collected. Manures from the two diet treatments were applied in a replicated laboratory chamber experiment, and ammonia emission was quantified using acid gas washing. In four seasonal field trials, manures from the two diet treatments were applied to two 10-m-diameter, circular, artificial feedyard surfaces, and ammonia emission was quantified using the integrated horizontal flux method. Manure from steers fed 11.5% CP diet had less urine, less urinary N, and a lesser fraction of total N in urine, compared with the 13.0% CP diet. Decreasing crude protein in beef cattle diets from 13 to 11.5% significantly decreased ammonia emission by 44% (p < 0.01) in the closed chamber laboratory experiment, and decreased mean daily ammonia flux by 30% (p = 0.10), 52% (p = 0.08), and 29% (p < 0.01) in summer, autumn, and spring field trials, respectively. No difference was observed in winter. On an annual basis, decreasing crude protein reduced daily ammonia flux by 28%. Reducing crude protein in beef cattle diets may provide the most practical and cost-effective way to reduce ammonia emissions from feedyards. PMID:16455840

  2. Sulfur passivation of GaAs surfaces: A model for reduced surface recombination without band flattening

    NASA Astrophysics Data System (ADS)

    Spindt, C. J.; Spicer, W. E.

    1989-10-01

    It has been shown by several workers that the passivation of GaAs surfaces using sulfides results in a large reduction in the surface recombination velocity accompanied by an increase in the band bending on n-type samples. This apparently contradictory pair of results leads to the suggestion that the responsible electronic states are a midgap donor compensated by an acceptor near the valence-band maximum. We explore the consequences of such a model, particularly when the midgap state is assumed to be a double donor. In the double donor case, simple qualitative arguments indicate that the surface recombination velocity can be reduced by a factor much greater than the reduction in surface-state density. The model is consistent with observations made using a variety of experimental techniques. A correlation between the electronic states and surface chemistry is made, and the As and Ga antisite defects are discussed as candidates for the donor and acceptor states.

  3. Imputing gene expression from optimally reduced probe sets

    PubMed Central

    Donner, Yoni; Feng, Ting; Benoist, Christophe; Koller, Daphne

    2012-01-01

    Measuring complete gene expression profiles for a large number of experiments is costly. We propose an approach in which a small subset of probes is selected based on a preliminary set of full expression profiles. In subsequent experiments, only the subset is measured, and the missing values are imputed. We develop several algorithms to simultaneously select probes and impute missing values, and demonstrate that these probe selection for imputation (PSI) algorithms can successfully reconstruct missing gene expression values in a wide variety of applications, as evaluated using multiple metrics of biological importance. We analyze the performance of PSI methods under varying conditions, provide guidelines for choosing the optimal method based on the experimental setting, and indicate how to estimate imputation accuracy. Finally, we apply our approach to a large-scale study of immune system variation. PMID:23064520

  4. Erythropoietin reduces the expression of myostatin in mdx dystrophic mice.

    PubMed

    Feder, D; Rugollini, M; Santomauro, A; Oliveira, L P; Lioi, V P; Santos, R dos; Ferreira, L G; Nunes, M T; Carvalho, M H; Delgado, P O; Carvalho, A A S; Fonseca, F L A

    2014-11-01

    Erythropoietin (EPO) has been well characterized as a renal glycoprotein hormone regulating red blood cell production by inhibiting apoptosis of erythrocyte progenitors in hematopoietic tissues. EPO exerts regulatory effects in cardiac and skeletal muscles. Duchenne muscular dystrophy is a lethal degenerative disorder of skeletal and cardiac muscle. In this study, we tested the possible therapeutic beneficial effect of recombinant EPO (rhEPO) in dystrophic muscles in mdx mice. Total strength was measured using a force transducer coupled to a computer. Gene expression for myostatin, transforming growth factor-β1 (TGF-β1), and tumor necrosis factor-α (TNF-α) was determined by quantitative real time polymerase chain reaction. Myostatin expression was significantly decreased in quadriceps from mdx mice treated with rhEPO (rhEPO = 0.60 ± 0.11, control = 1.07 ± 0.11). On the other hand, rhEPO had no significant effect on the expression of TGF-β1 (rhEPO = 0.95 ± 0.14, control = 1.05 ± 0.16) and TNF-α (rhEPO = 0.73 ± 0.20, control = 1.01 ± 0.09). These results may help to clarify some of the direct actions of EPO on skeletal muscle. PMID:25296358

  5. Saccharomyces cerevisiae expressing bacteriophage endolysins reduce Lactobacillus contamination during fermentation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the challenges facing the fuel ethanol industry is the management of bacterial contamination during fermentation. Lactobacillus species are the predominant contaminants that decrease the profitability of biofuel production by reducing ethanol yields and causing “stuck” fermentations, which i...

  6. Reduced expression of aquaporins in human intestinal mucosa in early stage inflammatory bowel disease

    PubMed Central

    Ricanek, Petr; Lunde, Lisa K; Frye, Stephan A; Støen, Mari; Nygård, Ståle; Morth, Jens P; Rydning, Andreas; Vatn, Morten H; Amiry-Moghaddam, Mahmood; Tønjum, Tone

    2015-01-01

    Objectives The aim of this study was to investigate the relationship between aquaporin (AQP) water channel expression and the pathological features of early untreated inflammatory bowel disease (IBD) in humans. Methods Patients suspected to have IBD on the basis of predefined symptoms, including abdominal pain, diarrhea, and/or blood in stool for more than 10 days, were examined at the local hospital. Colonoscopy with biopsies was performed and blood samples were taken. Patients who did not meet the diagnostic criteria for IBD and who displayed no evidence of infection or other pathology in the gut were included as symptomatic non-IBD controls. AQP1, 3, 4, 5, 7, 8, and 9 messenger RNA (mRNA) levels were quantified in biopsies from the distal ileum and colon by quantitative real-time polymerase chain reaction. Protein expression of selected AQPs was assessed by confocal microscopy. Through multiple alignments of the deduced amino acid sequences, the putative three-dimensional structures of AQP1, 3, 7, and 8 were modeled. Results AQP1, 3, 7, and 8 mRNAs were detected in all parts of the intestinal mucosa. Notably, AQP1 and AQP3 mRNA levels were reduced in the ileum of patients with Crohn’s disease, and AQP7 and AQP8 mRNA levels were reduced in the ileum and the colon of patients with ulcerative colitis. Immunofluorescence confocal microscopy showed localization of AQP3, 7, and 8 at the mucosal epithelium, whereas the expression of AQP1 was mainly confined to the endothelial cells and erythrocytes. The reduction in the level of AQP3, 7, and 8 mRNA was confirmed by immunofluorescence, which also indicated a reduction of apical immunolabeling for AQP8 in the colonic surface epithelium and crypts of the IBD samples. This could indicate loss of epithelial polarity in IBD, leading to disrupted barrier function. Conclusion AQPs 1 and 8 and the aquaglyceroporins AQPs 3 and 7 are the AQPs predominantly expressed in the lower intestinal tract of humans. Their expression is

  7. Structure and expression of two temperature-specific surface proteins in the ciliated protozoan Tetrahymena thermophila.

    PubMed Central

    Bannon, G A; Perkins-Dameron, R; Allen-Nash, A

    1986-01-01

    The presence of specific proteins (known as immobilization antigens) on the surface of the ciliated protozoan Tetrahymena thermophila is under environmental regulation. There are five different classes (serotypes) of surface proteins which appear on the cell surface when T. thermophila is cultured under different conditions of temperature or incubation medium; three of these are temperature dependent. The appearance of these proteins on the cell surface is mutually exclusive. We used polyclonal antibodies raised against 30 degrees C (designated SerH3)- and 40 degrees C (designated SerT)-specific surface antigens to study their structure and expression. We showed that these surface proteins contain at least one disulfide bridge. On sodium dodecyl sulfate-denaturing polyacrylamide gels, the nonreduced 30 degrees C- and 40 degrees C-specific surface proteins migrated with molecular sizes of 69 and 36 kilodaltons, respectively. The reduced forms of the proteins migrated with molecular sizes of 58 and 30 kilodaltons, respectively. The synthesis of the surface proteins responded rapidly and with a time course similar to that of the incubation temperature. The synthesis of each surface protein was greatly reduced within 1 h and undetectable by 2 h after a shift to the temperature at which the protein is not expressed. Surface protein synthesis resumed by the end of 1 h after a shift to the temperature at which the protein is expressed. The temperature-dependent induction of these surface proteins appears to be dependent on the synthesis of new mRNA, as indicated by a sensitivity to actinomycin D. Surface protein syntheses were mutually exclusive except at a transition temperature. At 35 degrees C both surface proteins were synthesized by a cell population. These data support the potential of this system as a model for the study of the effects of environmental factors on the genetic regulation of cell surface proteins. Images PMID:3537733

  8. PAX8 Expression in Ovarian Surface Epithelial Cells

    PubMed Central

    Adler, Emily; Mhawech-Fauceglia, Paulette; Gayther, Simon A; Lawrenson, Kate

    2015-01-01

    High-grade serous ovarian carcinoma (HGSOC) is usually diagnosed at a late stage and is associated with poor prognosis. Understanding early stage disease biology is essential in developing clinical biomarkers to detect HGSOC earlier. While recent studies indicate that HGSOCs arise from fallopian tube secretory epithelial cells (FTSECs), a considerable body of evidence also suggests that HGSOC can also arise from ovarian surface epithelial cells (OSECs). PAX8 is overexpressed in HGSOCs and expressed in FTSECs, but there are conflicting reports about PAX8 expression in OSECs. The purpose of this study was to comprehensively characterize PAX8 expression in a large series of OSECs, and to investigate the role of PAX8 in early HGSOC development. PAX8 protein expression was analyzed in the OSECs of 27 normal ovaries and 7 primary OSEC cultures using immunohistochemistry and immunofluorescent cytochemistry. PAX8 mRNA expression was quantified in 66 primary OSEC cultures. Cellular transformation was evaluated in OSECs expressing a PAX8 construct. PAX8 was expressed by 44-71% of OSECs. Calretinin and E-cadherin were frequently co-expressed with PAX8. Expression of PAX8 in OSECs decreased cellular migration (P=0.028), but had no other effects on cellular transformation. In addition, PAX8 expression was significantly increased (P=0.003) in an in vitro stepwise model of neoplastic transformation. In conclusion, PAX8 is frequently expressed by OSECs and endogenous levels of PAX8 expression are non-transforming. These data indicate that in OSECs PAX8 expression may represent a normal state and that OSECs may represent an origin of HGSOCs. PMID:26079312

  9. Cell surface expression and biosynthesis of epithelial Na+ channels.

    PubMed Central

    Prince, L S; Welsh, M J

    1998-01-01

    The epithelial Na+ channel (ENaC) complex is composed of three homologous subunits: alpha, beta and gamma. Mutations in ENaC subunits can increase the number of channels on the cell surface, causing a hereditary form of hypertension called Liddle's syndrome, or can decrease channel activity, causing pseudohypoaldosteronism type I, a salt-wasting disease of infancy. To investigate surface expression, we studied ENaC subunits expressed in COS-7 and HEK293 cells. Using surface biotinylation and protease sensitivity, we found that when individual ENaC subunits are expressed alone, they traffic to the cell surface. The subunits are glycosylated with high-mannose oligosaccharides, but seem to have the carbohydrate removed before they reach the cell surface. Moreover, subunits form a complex that cannot be disrupted by several non-ionic detergents. The pattern of glycosylation and detergent solubility/insolubility persists when the N-teminal and C-terminal cytoplasmic regions of ENaC are removed. With co-expression of all three ENaC subunits, the insoluble complex is the predominant species. These results show that ENaC and its family members are unique in their trafficking, biochemical characteristics and post-translational modifications. PMID:9841884

  10. Expression of the RNase III enzyme DROSHA is reduced during progression of human cutaneous melanoma

    PubMed Central

    Jafarnejad, Seyed Mehdi; Sjoestroem, Cecilia; Martinka, Magdalena; Li, Gang

    2016-01-01

    Aberrant expression of miRNAs and their biogenesis factors has been frequently observed in different types of cancer. We recently reported that expression of DICER1 is reduced in metastatic melanoma. Nevertheless, so far very little is known about the expression pattern of other miRNA biogenesis factors in this type of malignancy. Here, we investigated the expression pattern of DROSHA in a large set of melanocytic lesions by tissue microarray and immunohistochemistry (n = 409). We found that nuclear expression of DROSHA is markedly reduced in the early stages of melanoma progression (P = 0.0001) and is inversely correlated with melanoma thickness (P = 0.0001), AJCC stages (P = 0.0001), and ulceration status (P = 0.002). We also confirmed the reduced expression of nuclear DROSHA by a second specific antibody raised against a different region of the DROSHA protein. In addition, we observed that the reduced nuclear expression of DROSHA during melanoma progression is accompanied by an increased cytoplasmic expression of this protein (P = 0.0001). Finally, we found that expression pattern of DROSHA varies from that of DICER1 and concomitant loss of expression of both DICER1 and DROSHA confers the worse outcome for melanoma patients. Our results demonstrate a reduced nuclear expression of DROSHA which further highlights a perturbed miRNA biogenesis pathway in melanoma. In addition, the aberrant subcellular localization of DROSHA indicates possible deregulation in the mechanisms responsible for its proper localization in the nucleus. PMID:23370771

  11. Expression of ovule and integument-associated genes in reduced ovules of Santalales.

    PubMed

    Brown, Ryan H; Nickrent, Daniel L; Gasser, Charles S

    2010-01-01

    Santalales comprise mainly parasitic plants including mistletoes and sandalwoods. Bitegmic ovules similar to those found in most other angiosperms are seen in many members of the order, but other members exhibit evolutionary reductions to the unitegmic and ategmic conditions. In some mistletoes, extreme reduction has resulted in the absence of emergent ovules such that embryo sacs appear to remain embedded in placental tissues. Three santalalean representatives (Comandra, Santalum, and Phoradendron), displaying unitegmic, and ategmic ovules, were studied. Observed ovule morphologies were consistent with published reports, including Phoradendron serotinum, which we interpret as having reduced ategmic ovules, consistent with earlier reports on this species. For further understanding of the nature of the ovule reductions we isolated orthologs of the Arabidopsis genes AINTEGUMENTA (ANT) and BELL1 (BEL1), which are associated with ovule development in this species. We observed ovular expression of ANT and BEL1 in patterns largely resembling those seen in the integumented ovules of Arabidopsis. These genes were found to be expressed in the integument of unitegmic ovules and in the surface layers of ategmic ovules, and in some cases, expression of BEL1 was also observed in the surrounding carpel tissue. We hypothesize that ategmic ovules derive from a fusion of the integuments with the nucellus or that the nucellus has taken on some of the characteristics confined to integuments in ancestral species. PMID:20433462

  12. MULTIPLE IMAGING TECHNIQUES DEMONSTRATE THE MANIPULATION OF SURFACES TO REDUCE BACTERIAL CONTAMINATION

    EPA Science Inventory

    Surface imaging techniques were combined to determine appropriate manipulation of technologically important surfaces for commercial applications. Stainless steel surfaces were engineered to reduce bacterial contamination, biofilm formation, and corrosion during product processing...

  13. Downregulation of transferrin receptor surface expression by intracellular antibody

    SciTech Connect

    Peng Jilin; Wu Sha; Zhao Xiaoping; Wang Min; Li Wenhan; Shen Xin; Liu Jing; Lei Ping; Zhu Huifen; Shen Guanxin . E-mail: guanxin_shen@yahoo.com.cn

    2007-03-23

    To deplete cellular iron uptake, and consequently inhibit the proliferation of tumor cells, we attempt to block surface expression of transferrin receptor (TfR) by intracellular antibody technology. We constructed two expression plasmids (scFv-HAK and scFv-HA) coding for intracellular single-chain antibody against TfR with or without endoplasmic reticulum (ER) retention signal, respectively. Then they were transfected tumor cells MCF-7 by liposome. Applying RT-PCR, Western blotting, immunofluorescence microscopy and immunoelectron microscope experiments, we insure that scFv-HAK intrabody was successfully expressed and retained in ER contrasted to the secreted expression of scFv-HA. Flow cytometric analysis confirmed that the TfR surface expression was markedly decreased approximately 83.4 {+-} 2.5% in scFv-HAK transfected cells, while there was not significantly decrease in scFv-HA transfected cells. Further cell growth and apoptosis characteristics were evaluated by cell cycle analysis, nuclei staining and MTT assay. Results indicated that expression of scFv-HAK can dramatically induce cell cycle G1 phase arrest and apoptosis of tumor cells, and consequently significantly suppress proliferation of tumor cells compared with other control groups. For First time this study demonstrates the potential usage of anti-TfR scFv-intrabody as a growth inhibitor of TfR overexpressing tumors.

  14. Loss of NHE8 expression impairs ocular surface function in mice

    PubMed Central

    Xu, Hua; Zhao, Yang; Li, Jing; Wang, Mingwu; Lian, Fangru; Gao, Minghong

    2014-01-01

    Sodium/hydrogen exchanger (NHE) 8 is expressed at the apical membrane of the epithelial cells and plays important roles in neutral sodium absorption in the gastrointestinal tract and the kidney. It also has an important role in epithelial mucosal protection in the gastric gland and the intestine. Although NHE8 has broad tissue distribution, the precise location and the physiological role of NHE8 in the eye remain unknown. In the present study, we successfully detected the expression of NHE8 in the ocular surface by PCR and Western blot in human and mouse eyes. Immunohistochemistry staining located NHE8 protein at the plasma membrane of the epithelial cells in the conjunctiva, the cornea, and the lacrimal gland both in human and mouse. We also detected the expression of downregulated-in-adenoma (DRA, a Cl−/HCO3− transporter) in the ocular surface epithelial cells. Using NHE8−/− mouse model, we found that loss of NHE8 function resulted in reduced tear production and increased corneal staining. These NHE8−/− mice also showed increased expression of TNF-α and matrix metalloproteinase 9 (MMP9) genes. The expression of epithelial keratinization marker genes, small proline-rich protein 2h (Sprr2h) and transglutaminase 1 (Tgm1), were also increased in NHE8−/− eyes. Furthermore, DRA expression in NHE8−/− mice was reduced in the conjunctiva, the cornea, and the lacrimal glands in association with a reduction in conjunctival mucosal pH. Altered ocular surface function and reduced epithelial DRA expression in NHE8−/− mice suggest that the role of NHE8 in ocular surface tissue involve in tear production and ocular epithelial protection. This study reveals a potential novel mechanism of dry eye condition involving abnormal NHE8 function. PMID:25377091

  15. Significantly reduced expression of the proteoglycan decorin in Alzheimer's disease fibroblasts

    PubMed Central

    Brandan, Enrique; Melo, Francisco; García, María; Contreras, Maribel

    1996-01-01

    Aims—To investigate whether proteoglycan synthesis is altered in skin fibroblasts in patients with Alzheimer's disease compared with normal subjects. Methods—Cell lines obtained from donors with Alzheimer's disease and healthy controls were incubated with radioactive sulphate. The proteoglycans synthesised were determined and analysed by chromatographic, sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and glycosaminoglycans-lyase treatment. The amount of decorin synthesised by each cell line was quantified using western blot analysis. Transcripts for human decorin were determined using northern blot analysis. Results—No significant changes in total sulphate incorporation and glycos-aminoglycan (GAG) composition were detected in the incubation media of these cells. However, chromatographic and SDS-PAGE analysis of the proteoglycans secreted by the cell lines showed that a dermatan sulphate proteoglycan of 150-125 kilodaltons was substantially reduced in Alzheimer's disease fibroblasts. The molecular characteristics of this proteoglycan correspond to decorin. Western blot analysis indicated that decorin was reduced in Alzheimer's disease incubation medium compared with normal medium. Northern blotting indicated that in Alzheimer's disease fibroblasts decorin transcripts were significantly reduced compared with normal fibroblasts. Glypican concentrations, a cell surface heparan sulphate proteoglycan, remained the same. Conclusions—These results strongly suggest that the expression and synthesis of decorin is affected in Alzheimer's disease skin fibroblasts. Images PMID:16696102

  16. Landfill disposal of unused medicines reduces surface water releases.

    PubMed

    Tischler, Lial; Buzby, Mary; Finan, Douglas S; Cunningham, Virginia L

    2013-01-01

    The pharmaceutical industry is conducting research to evaluate the pathways and fate of active pharmaceutical ingredients from the consumer to surface waters. One potential pathway identified by the researchers is the disposal of unused pharmaceutical products that are discarded by consumers in household trash and disposed of in municipal solid waste landfills. This study was designed to evaluate relative amounts of surface water exposures through the landfill disposal pathway compared to patient use and flushing of unused medicine pathways. The estimated releases to surface water of 24 example active pharmaceutical ingredients (APIs) in landfill leachate were calculated for 3 assumed disposal scenarios: 5%, 10%, and 15% of the total annual quantity of API sold is discarded and unused. The estimated releases from landfills to surface waters, after treatment of the leachate, were compared to the total amount of each example API that would be released to surface waters from publicly owned treatment works, generated by patient use and excretion. This study indicates that the disposal of unused medications in municipal solid waste landfills effectively eliminates the unused medicine contribution of APIs to surface waters; greater than 99.9% of APIs disposed of in a landfill are permanently retained. PMID:22556107

  17. Quantitative Surface-Enhanced Raman for Gene Expression Estimation

    PubMed Central

    Sun, Lan; Irudayaraj, Joseph

    2009-01-01

    We demonstrate for the first time, to our knowledge, a unique gene expression assay by surface-enhanced Raman scattering (SERS) using nonfluorescent Raman labels to quantify gene expression at the resolution of alternative splicing using RNA extracted from cancer cells without any amplification steps. Our approach capitalizes on the inherent plasmon-phonon mode of SERS substrates as a self-referencing standard for the detection and quantification of genetic materials. A strategy integrating S1 nuclease digestion with SERS detection was developed to quantify the expression levels of splice junction Δ(9,10), a segment of the breast cancer susceptibility gene 1 (BRCA1) from MCF-7 and MDA-MB-231 cells. Quantification results were cross-validated using two Raman tags and qualitatively confirmed by RT-PCR. Our methodology based on SERS technology provides reliable gene expression data with high sensitivity, bypassing the intricacies involved in fabricating a consistent SERS substrate. PMID:19486693

  18. Elevated expression of ABCB5 in ocular surface squamous neoplasia

    PubMed Central

    Jongkhajornpong, Passara; Nakamura, Takahiro; Sotozono, Chie; Nagata, Maho; Inatomi, Tsutomu; Kinoshita, Shigeru

    2016-01-01

    ATP-binding cassette subfamily B member 5 (ABCB5) is a new member of the ATP-binding cassette superfamily and has been reported as a novel marker for limbal stem cell (LSC), which is essential for corneal homeostasis. ABCB5 expression has also been discovered in the subpopulation of several cancer cells containing the cancer stem cell (CSC). However, the pathogenetic relationship between LSC and CSC and ABCB5 in the ocular surface squamous neoplasm (OSSN) is still entirely unknown. To improve understanding of the role of ABCB5 in OSSN, we performed immunohistochemistry for ABCB5 in nine OSSN case series. While expression of ABCB5 is restricted to the basal epithelial cell layer in the normal limbus, elevated expressions of ABCB5 were clearly observed in all OSSN, and there was some breadth in the range of intensity of ABCB5 expression. Interestingly, the elevated expression patterns of ABCB5 in OSSN could be classified in three categories: perivascular, marginal and diffuse patterns. Our findings demonstrated for the first time that the expression of ABCB5 was upregulated in OSSN and that elevated expression of ABCB5 may be involved in the pathogenesis of OSSN. PMID:26843453

  19. Reduced fouling of ultrafiltration membranes via surface fluorination

    SciTech Connect

    Sedath, R.H.; Yates, S.F.; Li, N.N.

    1993-03-01

    Surface fluorination can affect significantly the performance of an ultrafiltration membrane used to concentrate a food-related stream. Membranes fluorinated and tested as flat sheets exhibit higher initial fluxes, and do not foul as rapidly as untreated membranes. This improvement is linked to increased surface hydrophilicity, as shown in decreased contact angle with water. This increased hydrophilicity, in turn, is linked to the addition of fluorine and oxygen to the surface. The pilot plant study did-not show the difference in membrane flux and fouling observed in the flat sheet study. Instead, fluorinated and unfluorinated modules behaved similarly. Fouling by potato waste feed was severe and resulted in formation of an extensive gel layer within the module on the membrane surface. XPS, SEM and FTIR indicate that buildup of organic material occurred on both fluorinated and unfluorinated membranes, but SEM indicates that a fibrous mat of material was observed only on the nonfluorinated membrane. We conclude that in the pilot study, membrane fouling and gel formation were so extensive that the surface interaction effect was overwhelmed.

  20. Face in profile view reduces perceived facial expression intensity: an eye-tracking study.

    PubMed

    Guo, Kun; Shaw, Heather

    2015-02-01

    Recent studies measuring the facial expressions of emotion have focused primarily on the perception of frontal face images. As we frequently encounter expressive faces from different viewing angles, having a mechanism which allows invariant expression perception would be advantageous to our social interactions. Although a couple of studies have indicated comparable expression categorization accuracy across viewpoints, it is unknown how perceived expression intensity and associated gaze behaviour change across viewing angles. Differences could arise because diagnostic cues from local facial features for decoding expressions could vary with viewpoints. Here we manipulated orientation of faces (frontal, mid-profile, and profile view) displaying six common facial expressions of emotion, and measured participants' expression categorization accuracy, perceived expression intensity and associated gaze patterns. In comparison with frontal faces, profile faces slightly reduced identification rates for disgust and sad expressions, but significantly decreased perceived intensity for all tested expressions. Although quantitatively viewpoint had expression-specific influence on the proportion of fixations directed at local facial features, the qualitative gaze distribution within facial features (e.g., the eyes tended to attract the highest proportion of fixations, followed by the nose and then the mouth region) was independent of viewpoint and expression type. Our results suggest that the viewpoint-invariant facial expression processing is categorical perception, which could be linked to a viewpoint-invariant holistic gaze strategy for extracting expressive facial cues. PMID:25531122

  1. Reduced Viscosity of Free Surface in Entangled Polymer Melt Films

    NASA Astrophysics Data System (ADS)

    Koga, Tad; Li, C.; Endoh, M.; Koo, J.; Rafailovich, M.; Narayanan, S.; Lee, D.; Lurio, L.; Sinha, S.

    2010-03-01

    The dynamics of polymer chains near the surface of a melt and within thin films remains a subject of inquiry along with the nature of the glass transition in these systems. By embedding ``dilute'' gold nanoparticles in single polystyrene thin films as ``markers'', we could probe the local viscosity of the free surface at temperatures far above the glass transition temperature (Tg). The technique used was X-ray photon correlation spectroscopy with resonance-enhanced X-ray scattering. The results clearly showed the viscosity was about 30 % lower than the rest of the film. We found that this reduction is strongly associated with chain entanglements at the free surface rather than the reduction in Tg.

  2. Surface modification of clutch plates to reduce disengaged drag torque

    NASA Astrophysics Data System (ADS)

    Aphale, Chinar R.

    2005-11-01

    Viscous drag torque in disengaged clutches is a significant source of power loss in modern transportation. The main way to reduce this drag torque is to introduce air between the plates when disengaged without reducing the transmission fluid flow eventually needed for reengagement. Six different groove patterns are tested experimentally to determine which have the lowest drag characteristics. Our computations using Fluent showed that the contact angle made by oil with the stationary plate is critical in determining aeration initiation. Experiments coating the stationary plate with an oleophobic substance like Teflon, confirmed these simulations. We will show torque comparisons and visualization through a quartz disk acting as one of the clutch plates.

  3. Surface application of biochar to reduce chloropicrin emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biochar is the carbon-enriched and porous material produced by heating organic material under conditions of limited or no oxygen. As biochar has a large surface area and strong sorption capacity, it can enhance the sequestration of organic contaminants such as pesticides in soil. Chloropicrin (CP) i...

  4. Insecticides reduce survival and the expression of traits associated with carnivory of carnivorous plants.

    PubMed

    Jennings, David E; Congelosi, Alexandra M; Rohr, Jason R

    2012-03-01

    While agrochemical pollution is thought to be an important conservation threat to carnivorous plants, the effects of insecticides on these taxa have not been quantified previously. Using a combination of lab- and field-based experiments, we tested the effects of commercial and technical grades of three widely used insecticides (carbaryl, lambda-cyhalothrin, and malathion) on survival and the expression of traits associated with carnivory of pink sundews (Drosera capillaris) and Venus flytraps (Dionaea muscipula). Commercial grades were generally more harmful than technical grades under lab and field conditions, but all three insecticides were capable of reducing both survival and the expression of traits associated with carnivory within recommended application rates. However, pink sundews appeared to be more susceptible to insecticides than Venus flytraps, perhaps because of larger numbers of digestive glands on the leaf surfaces. We make several recommendations for future research directions, such as examining the long-term effects of insecticides on carnivorous plant populations, for example in terms of growth rates and fitness. Additionally, future research should include representative species from a wider-range of carnivorous plant growth forms, and explore the mechanism by which insecticides are harming the plants. Given the effects we observed in the present study, we suggest that the use of insecticides should be carefully managed in areas containing vulnerable carnivorous plant species. PMID:22076028

  5. Reduced ABCB1 Expression and Activity in the Presence of Acrylic Copolymers

    PubMed Central

    Mohammadzadeh, Ramin; Baradaran, Behzad; Valizadeh, Hadi; Yousefi, Bahman; Zakeri-Milani, Parvin

    2014-01-01

    Purpose: P-glycoprotein (P-gp; ABCB1), an integral membrane protein in the apical surface of human intestinal epithelial cells, plays a crucial role in the intestinal transport and efflux leading to changes in the bioavailability of oral pharmaceutical compounds. This study was set to examine the potential effects of three Eudragits RL100, S100 and L100 on the intestinal epithelial membrane transport of rhodammine-123 (Rho-123), a substrate of P-gp using a monolayer of human colon cancer cell line (Caco-2). Methods: The least non-cytotoxic concentrations of the excipients were assessed in Caco-2 cells by the MTT assay. Then the transepithelial transport of Rho-123 across Caco-2 monolayers was determined with a fluorescence spectrophotometer. Besides, the expression of the P-gp in cells exposed to the polymers was demonstrated using Western-blotting analysis. Results: Treatment of cells with Eudragit RL100 and L100 led to a very slight change while Eudragit S100 showed 61% increase in Rho-123 accumulation (P<0.001) and also reduced transporter expression. Conclusion: Our studies suggest that using proper concentrations of the Eudragit S100 in drug formulation would improve intestinal permeability and absorption of p-gp substrate drugs. PMID:24754004

  6. Fucoidan reduces secretion and expression of vascular endothelial growth factor in the retinal pigment epithelium and reduces angiogenesis in vitro.

    PubMed

    Dithmer, Michaela; Fuchs, Sabine; Shi, Yang; Schmidt, Harald; Richert, Elisabeth; Roider, Johann; Klettner, Alexa

    2014-01-01

    Fucoidan is a polysaccharide isolated from brown algae which is of current interest for anti-tumor therapy. In this study, we investigated the effect of fucoidan on the retinal pigment epithelium (RPE), looking at physiology, vascular endothelial growth factor (VEGF) secretion, and angiogenesis, thus investigating a potential use of fucoidan for the treatment of exudative age-related macular degeneration. For this study, human RPE cell line ARPE-19 and primary porcine RPE cells were used, as well as RPE/choroid perfusion organ cultures. The effect of fucoidan on RPE cells was investigated with methyl thiazolyl tetrazolium--assay, trypan blue exclusion assay, phagocytosis assay and a wound healing assay. VEGF expression was evaluated in immunocytochemistry and Western blot, VEGF secretion was evaluated in ELISA. The effect of fucoidan on angiogenesis was tested in a Matrigel assay using calcein-AM vital staining, evaluated by confocal laser scanning microcopy and quantitative image analysis. Fucoidan displays no toxicity and does not diminish proliferation or phagocytosis, but reduces wound healing in RPE cells. Fucoidan decreases VEGF secretion in RPE/choroid explants and RPE cells. Furthermore, it diminishes VEGF expression in RPE cells even when co-applied with bevacizumab. Furthermore, fucoidan reduces RPE-supernatant- and VEGF-induced angiogenesis of peripheral endothelial cells. In conclusion, fucoidan is a non-toxic agent that reduces VEGF expression and angiogenesis in vitro and may be of interest for further studies as a potential therapy against exudative age-related macular degeneration. PMID:24558482

  7. Improving MRI surface coil decoupling to reduce B1 distortion

    NASA Astrophysics Data System (ADS)

    Larson, Christian

    As clinical MRI systems continue to advance, larger focus is being given to image uniformity. Good image uniformity begins with generating uniform magnetic fields, which are easily distorted by induced currents on receive-only surface coils. It has become an industry standard to combat these induced currents by placing RF blocking networks on surface coils. This paper explores the effect of blocking network impedance of phased array surface coils on B1 distortion. It has been found and verified, that traditional approaches for blocking network design in complex phased arrays can leave undesirable B1 distortions at 3 Tesla. The traditional approach of LC tank blocking is explored, but shifts from the idea that higher impedance equals better B1 distortion at 3T. The result is a new design principle for a tank with a finite inductive reactance at the Larmor Frequency. The solution is demonstrated via simulation using a simple, single, large tuning loop. The same loop, along with a smaller loop, is used to derive the new design principle, which is then applied to a complex phased array structure.

  8. On the Use of Surface Porosity to Reduce Unsteady Lift

    NASA Technical Reports Server (NTRS)

    Tinetti, Ana F.; Kelly, Jeffrey J.; Bauer, Steven X. S.; Thomas, Russell H.

    2001-01-01

    An innovative application of existing technology is proposed for attenuating the effects of transient phenomena, such as rotor-stator and rotor-strut interactions, linked to noise and fatigue failure in turbomachinery environments. A computational study was designed to assess the potential of passive porosity technology as a mechanism for alleviating interaction effects by reducing the unsteady lift developed on a stator airfoil subject to wake impingement. The study involved a typical high bypass fan Stator airfoil (solid baseline and several porous configurations), immersed in a free field and exposed to the effects of a transversely moving wake. It was found that, for the airfoil under consideration, the magnitude of the unsteady lift could be reduced more than 18% without incurring significant performance losses.

  9. Analysis of the cell surface expression of cytokine receptors using the surface protein biotinylation method.

    PubMed

    Pavel, Mahmud Arif; Lam, Clarissa; Kashyap, Parul; Salehi-Najafabadi, Zahra; Singh, Gurpreet; Yu, Yong

    2014-01-01

    Cytokines are pleiotropic, low-molecular-weight proteins that regulate the immune responses to infection and inflammation. They stimulate the immune responses by binding to cytokine receptors on the cell plasma membrane. Thus, knowledge of the expression level of particular cytokine receptors on cell surface is crucial for understanding the cytokine function and regulation. One of the techniques to explore the membrane embedded cytokine receptors is cell surface biotinylation. Biotinylated surface proteins can be rapidly purified through the strong interaction between biotin and streptavidin. Here, we describe the procedure for surface biotinylation and purification of biotinylated cytokine receptors for further downstream analysis. PMID:24908305

  10. Reduced expression of Autographa californica nucleopolyhedrovirus ORF34, an essential gene, enhances heterologous gene expression

    SciTech Connect

    Salem, Tamer Z.; Zhang, Fengrui; Thiem, Suzanne M.

    2013-01-20

    Autographa californica multiple nucleopolyhedrovirus ORF34 is part of a transcriptional unit that includes ORF32, encoding a viral fibroblast growth factor (FGF) and ORF33. We identified ORF34 as a candidate for deletion to improve protein expression in the baculovirus expression system based on enhanced reporter gene expression in an RNAi screen of virus genes. However, ORF34 was shown to be an essential gene. To explore ORF34 function, deletion (KO34) and rescue bacmids were constructed and characterized. Infection did not spread from primary KO34 transfected cells and supernatants from KO34 transfected cells could not infect fresh Sf21 cells whereas the supernatant from the rescue bacmids transfection could recover the infection. In addition, budded viruses were not observed in KO34 transfected cells by electron microscopy, nor were viral proteins detected from the transfection supernatants by western blots. These demonstrate that ORF34 is an essential gene with a possible role in infectious virus production.

  11. Detection of CXCR2 cytokine receptor surface expression using immunofluorescence.

    PubMed

    Lam, Clarissa; Pavel, Mahmud Arif; Kashyap, Parul; Salehi-Najafabadi, Zahra; Valentino, Victoria; Yu, Yong

    2014-01-01

    The interleukin-8 (IL-8, CXCL8) chemokine, also known as the neutrophil chemotactic factor, is a cytokine that plays a key role in inflammatory response, cell proliferation, migration, and survival. IL-8 expression is increased not only in inflammatory disorders, but also in many types of cancer, including prostate cancer. IL-8 acts as a ligand for the C-X-C chemokine receptor 2 (CXCR2) protein present on the cell plasma membrane. Binding of the IL-8 ligand to the CXCR2 receptor results in an intracellular signaling pathway mediated by GTP binding proteins coupled to the receptor itself. Knowledge of the CXCR2 expression levels facilitates the understanding of the role and function of IL-8. In this chapter, we describe a protocol that uses the immunofluorescence method and confocal microscopy to analyze the CXCR2 surface expression in human prostate cancer cells. However, this protocol is easily adaptable to analyze the surface expression of other cytokine receptors in different cell types. PMID:24908306

  12. Surface Polysaccharide Mutants Reveal that Absence of O Antigen Reduces Biofilm Formation of Actinobacillus pleuropneumoniae

    PubMed Central

    Hathroubi, S.; Hancock, M. A.; Langford, P. R.; Tremblay, Y. D. N.; Labrie, J.

    2015-01-01

    Actinobacillus pleuropneumoniae is a Gram-negative bacterium belonging to the Pasteurellaceae family and the causative agent of porcine pleuropneumonia, a highly contagious lung disease causing important economic losses. Surface polysaccharides, including lipopolysaccharides (LPS) and capsular polysaccharides (CPS), are implicated in the adhesion and virulence of A. pleuropneumoniae, but their role in biofilm formation is still unclear. In this study, we investigated the requirement for these surface polysaccharides in biofilm formation by A. pleuropneumoniae serotype 1. Well-characterized mutants were used: an O-antigen LPS mutant, a truncated core LPS mutant with an intact O antigen, a capsule mutant, and a poly-N-acetylglucosamine (PGA) mutant. We compared the amount of biofilm produced by the parental strain and the isogenic mutants using static and dynamic systems. Compared to the findings for the biofilm of the parental or other strains, the biofilm of the O antigen and the PGA mutants was dramatically reduced, and it had less cell-associated PGA. Real-time PCR analyses revealed a significant reduction in the level of pgaA, cpxR, and cpxA mRNA in the biofilm cells of the O-antigen mutant compared to that in the biofilm cells of the parental strain. Specific binding between PGA and LPS was consistently detected by surface plasmon resonance, but the lack of O antigen did not abolish these interactions. In conclusion, the absence of the O antigen reduces the ability of A. pleuropneumoniae to form a biofilm, and this is associated with the reduced expression and production of PGA. PMID:26483403

  13. Immobilization of bioactive plasmin reduces the thrombogenicity of metal surfaces.

    PubMed

    Wise, Steven G; Michael, Praveesuda L; Waterhouse, Anna; Santos, Miguel; Filipe, Elysse; Hung, Juichien; Kondyurin, Alexey; Bilek, Marcela M M; Ng, Martin K C

    2015-12-01

    Components of many vascular prostheses including endovascular stents, heart valves and ventricular assist devices are made using metal alloys. In these blood contacting applications, metallic devices promote blood clotting, which is managed clinically by profound platelet suppression and/or anticoagulation. Here it is proposed that the localized immobilization of bioactive plasmin, a critical mediator of blood clot stability, may attenuate metallic prosthesis-induced thrombus formation. Previously described approaches to covalently immobilize biomolecules on implantable materials have relied on complex chemical linker chemistry, increasing the possibility of toxic side effects and reducing bioactivity. We utilize a plasma deposited thin film platform to covalently immobilize biologically active plasmin on stainless steel substrates, including stents. A range of in vitro whole blood assays demonstrate striking reductions in thrombus formation. This approach has profound potential to improve the efficacy of a wide range of metallic vascular implants. PMID:26551872

  14. Detection of embryonic stem cell lysate biomarkers by surface plasmon resonance with reduced nonspecific adsorption.

    PubMed

    Tyagi, Deependra; Perez, Javier Batista; Nand, Amita; Zhiqiang, Cheng; Wang, Peizhe; Na, Jie; Zhu, Jingsong

    2015-02-15

    Surface plasmon resonance imaging (SPRi) has emerged as a versatile biosensor to detect a wide range of biomolecular interactions with divergent potential applications. However, the use of this advanced-level technology for stem cell lysate study is still not much explored. Cell lysates are significant biological analytes used for disease diagnostics and proteomic studies, but their complex nature limits their use as an analyte for SPRi biosensors. Here, we review the problems associated with the use of SPRi for stem cell lysate study and examine the role of surface chemistry, running buffer, and blocking solution in order to minimize nonspecific adsorption (NSA). We detect the expression of Oct4, Sox2, Nanog, Rex1, and Lin28 biomarkers present in mouse embryonic stem cell (mESC) lysate against their corresponding antibodies immobilized on the sensor surface with reduced NSA. The current study shows that the conjunction of SPRi and microarray can be used as a label-free, high-throughput, and rapid technique for detection of biomarkers and their relative abundance in stem cell lysate study. PMID:25447493

  15. Rab25 influences functional Cav1.2 channel surface expression in arterial smooth muscle cells.

    PubMed

    Bannister, John P; Bulley, Simon; Leo, M Dennis; Kidd, Michael W; Jaggar, Jonathan H

    2016-06-01

    Plasma membrane-localized CaV1.2 channels are the primary calcium (Ca(2+)) influx pathway in arterial smooth muscle cells (myocytes). CaV1.2 channels regulate several cellular functions, including contractility and gene expression, but the trafficking pathways that control the surface expression of these proteins are unclear. Similarly, expression and physiological functions of small Rab GTPases, proteins that control vesicular trafficking in arterial myocytes, are poorly understood. Here, we investigated Rab proteins that control functional surface abundance of CaV1.2 channels in cerebral artery myocytes. Western blotting indicated that Rab25, a GTPase previously associated with apical recycling endosomes, is expressed in cerebral artery myocytes. Immunofluorescence Förster resonance energy transfer (immunoFRET) microscopy demonstrated that Rab25 locates in close spatial proximity to CaV1.2 channels in myocytes. Rab25 knockdown using siRNA reduced CaV1.2 surface and intracellular abundance in arteries, as determined using arterial biotinylation. In contrast, CaV1.2 was not located nearby Rab11A or Rab4 and CaV1.2 protein was unaltered by Rab11A or Rab4A knockdown. Rab25 knockdown resulted in CaV1.2 degradation by a mechanism involving both lysosomal and proteasomal pathways and reduced whole cell CaV1.2 current density but did not alter voltage dependence of current activation or inactivation in isolated myocytes. Rab25 knockdown also inhibited depolarization (20-60 mM K(+)) and pressure-induced vasoconstriction (myogenic tone) in cerebral arteries. These data indicate that Rab25 is expressed in arterial myocytes where it promotes surface expression of CaV1.2 channels to control pressure- and depolarization-induced vasoconstriction. PMID:27076616

  16. Plasmodium falciparum Variant Surface Antigen Expression Patterns during Malaria

    PubMed Central

    2005-01-01

    The variant surface antigens expressed on Plasmodium falciparum–infected erythrocytes are potentially important targets of immunity to malaria and are encoded, at least in part, by a family of var genes, about 60 of which are present within every parasite genome. Here we use semi-conserved regions within short var gene sequence “tags” to make direct comparisons of var gene expression in 12 clinical parasite isolates from Kenyan children. A total of 1,746 var clones were sequenced from genomic and cDNA and assigned to one of six sequence groups using specific sequence features. The results show the following. (1) The relative numbers of genomic clones falling in each of the sequence groups was similar between parasite isolates and corresponded well with the numbers of genes found in the genome of a single, fully sequenced parasite isolate. In contrast, the relative numbers of cDNA clones falling in each group varied considerably between isolates. (2) Expression of sequences belonging to a relatively conserved group was negatively associated with the repertoire of variant surface antigen antibodies carried by the infected child at the time of disease, whereas expression of sequences belonging to another group was associated with the parasite “rosetting” phenotype, a well established virulence determinant. Our results suggest that information on the state of the host–parasite relationship in vivo can be provided by measurements of the differential expression of different var groups, and need only be defined by short stretches of sequence data. PMID:16304608

  17. Leukocyte Cell Surface Proteinases: Regulation of Expression, Functions, and Mechanisms of Surface Localization

    PubMed Central

    Owen, Caroline A.

    2008-01-01

    A number of proteinases are expressed on the surface of leukocytes including members of the serine, metallo-, and cysteine proteinase superfamilies. Some proteinases are anchored to the plasma membrane of leukocytes by a transmembrane domain or a glycosyl phosphatidyl inositol (GPI) anchor. Other proteinases bind with high affinity to classical receptors, or with lower affinity to integrins, proteoglycans, or other leukocyte surface molecules. Leukocyte surface levels of proteinases are regulated by: 1) cytokines, chemokines, bacterial products, and growth factors which stimulate synthesis and/or release of proteinase by cells; 2) the availability of surface binding sites for proteinases; and/or 3) internalization or shedding of surface-bound proteinases. The binding of proteinases to leukocyte surfaces serves many functions including: 1) concentrating the activity of proteinases to the immediate pericellular environment; 2) facilitating pro-enzyme activation; 3) increasing proteinase stability and retention in the extracellular space; 4) regulating leukocyte function by proteinases signaling through cell surface binding sites or other surface proteins; and 5) protecting proteinases from inhibition by extracellular proteinase inhibitors. There is strong evidence that membrane-associated proteinases on leukocytes play critical roles in wound healing, inflammation, extracellular matrix remodeling, fibrinolysis, and coagulation. This review will outline the biology of membrane-associated proteinases expressed by leukocytes and their roles in physiologic and pathologic processes. PMID:18329945

  18. Surface-based mapping of gene expression and probabilistic expression maps in the mouse cortex.

    PubMed

    Ng, Lydia; Lau, Chris; Sunkin, Susan M; Bernard, Amy; Chakravarty, M Mallar; Lein, Ed S; Jones, Allan R; Hawrylycz, Michael

    2010-02-01

    The Allen Brain Atlas (ABA, www.brain-map.org) is a genome wide, spatially registered collection of cellular resolution in situ hybridization gene expression image data of the C57Bl/6J mouse brain. Derived from the ABA, the Anatomic Gene Expression Atlas (AGEA, http://mouse.brain-map.org/agea) has demonstrated both laminar and areal spatial gene expression correlations in the mouse cortex. While the mouse cortex is lissencephalic, its curvature and substantial bending in boundary areas renders it difficult to visualize and analyze laminar versus areal effects in a rectilinear coordinate framework. In context of human and non-human primate cortex, surface-based representation has proven useful for understanding relative locations of laminar, columnar, and areal features. In this paper, we describe a methodology for constructing surface-based flatmaps of the mouse cortex that enables mapping of gene expression data from individual genes in the ABA, or probabilistic expression maps from the AGEA, to identify and visualize genetic relationships between layers and areas. PMID:19818854

  19. Effects of space flight on surface marker expression

    NASA Astrophysics Data System (ADS)

    Sonnenfeld, G.

    1999-01-01

    Space flight has been shown to affect expression of several cell surface markers. These markers play important roles in regulation of immune responses, including CD4 and CD8. The studies have involved flight of experimental animals and humans followed by analysis of tissue samples (blood in humans, rats and monkeys, spleen, thymus, lymph nodes and bone marrow in rodents). The degree and direction of the changes induced by space flight have been determined by the conditions of the flight. Also, there may be compartmentalization of the response of surface markers to space flight, with differences in the response of cells isolated from blood and local immune tissue. The same type of compartmentalization was also observed with cell adhesion molecules (integrins). In this case, the expression of integrins from lymph node cells differed from that of splenocytes isolated from rats immediately after space flight. Cell culture studies have indicated that there may be an inhibition in conversion of a precursor cell line to cells exhibiting mature macrophage characteristics after space flight, however, these experiments were limited as a result of technical difficulties. In general, it is clear that space flight results in alterations of cell surface markers. The biological significance of these changes remains to be established.

  20. Expression of Plasmodium falciparum surface antigens in Escherichia coli.

    PubMed Central

    Ardeshir, F; Flint, J E; Reese, R T

    1985-01-01

    The asexual blood stages of the human malarial parasite Plasmodium falciparum produce many antigens, only some of which are important for protective immunity. Most of the putative protective antigens are believed to be expressed in schizonts and merozoites, the late stages of the asexual cycle. With the aim of cloning and characterizing genes for important parasite antigens, we used late-stage P. falciparum mRNA to construct a library of cDNA sequences inserted in the Escherichia coli expression vector pUC8. Nine thousand clones from the expression library were immunologically screened in situ with serum from Aotus monkeys immune to P. falciparum, and 95 clones expressing parasite antigens were identified. Mice were immunized with lysates from 49 of the bacterial clones that reacted with Aotus sera, and the mouse sera were tested for their reactivity with parasite antigens by indirect immunofluorescence, immunoprecipitation, and immunoblotting assays. Several different P. falciparum antigens were identified by these assays. Indirect immunofluorescence studies of extracellular merozoites showed that three of these antigens appear to be located on the merozoite surface. Thus, we have identified cDNA clones to three different P. falciparum antigens that may be important in protective immunity. Images PMID:3887406

  1. The diagnostic utility of reduced immunohistochemical expression of SMARCB1 in synovial sarcomas: a validation study.

    PubMed

    Ito, Junko; Asano, Naofumi; Kawai, Akira; Yoshida, Akihiko

    2016-01-01

    Synovial sarcoma is a malignant mesenchymal neoplasm of uncertain histogenesis, characterized by a specific SS18-SSX fusion. The diagnosis of synovial sarcoma can be challenging based on morphology and conventional immunohistochemistry alone, and identification of the fusion gene by molecular genetics may be necessary for diagnosis. Several recent studies have demonstrated the diagnostic utility of the reduced expression of SMARCB1 in synovial sarcomas as measured using immunohistochemistry. Therefore, we undertook a validation study using synovial sarcomas and other spindle or round cell tumors that could enter differential diagnosis of monophasic or poorly differentiated synovial sarcomas. Among 36 synovial sarcomas that were successfully evaluated, the expression of SMARCB1 was diffusely reduced in 33 cases (92%) at variable degrees. In contrast, the expression of SMARCB1 was not reduced in any of the 93 evaluable non-synovial sarcoma tumors (5 thymomas, 5 sarcomatoid mesotheliomas, 10 schwannomas, 9 mesenchymal chondrosarcomas, 20 solitary fibrous tumors, 19 Ewing sarcomas, and 25 malignant peripheral nerve sheath tumors). A few schwannomas and malignant peripheral nerve sheath tumors showed mosaic or complete loss of SMARCB1 expression. Reduced expression of SMARCB1 immunoreactivity was therefore found to be highly sensitive and specific for synovial sarcoma, and can be useful for rapidly and accurately confirming the diagnosis of synovial sarcoma. This reduction in SMARCB1 expression likely reflects the BAF47 ejection mechanism of the SS18-SSX fusion product and can therefore be viewed as an indirect visualization of this fusion product. PMID:26520417

  2. Interferon-γ Reduces Melanosomal Antigen Expression and Recognition of Melanoma Cells by Cytotoxic T Cells

    PubMed Central

    Le Poole, I. Caroline; Riker, Adam I.; Quevedo, M. Eugenia; Stennett, Lawrence S.; Wang, Ena; Marincola, Francesco M.; Kast, W. Martin; Robinson, June K.; Nickoloff, Brian J.

    2002-01-01

    In malignant melanoma, tumor-infiltrating lymphocytes are frequently reactive with melanosomal antigens. Achieving complete remissions by peptide therapy is frequently hampered by metastases evading immune recognition. The tumor microenvironment seems to favor reduced expression of target antigens by melanoma cells. Among candidate factors, interferon-γ (IFN-γ) (102 to 103 U/ml) suppressed expression of antigens MART-1, TRP-1, and gp100 by M14 melanoma cells as shown by immunohistology and fluorescence-activated cell sorting analysis, reducing MART-1 expression by >65%. Northern blot analysis revealed that reduced expression was regulated at the transcriptional level, demonstrating a 79% reduction in MART-1 transcript abundance after 32 hours of IFN-γ treatment. To evaluate consequences of IFN-γ exposure for immune recognition, MART-1-responsive T cells were reacted with pretreated HLA-matched melanoma cells. Cytotoxicity was reduced up to 78% by IFN-γ pretreatment, and was restored by addition of MART-1 peptide AAGIGILTV for 2 hours. Examination of melanoma lesions by quantitative reverse transcriptase-polymerase chain reaction revealed up to 188-fold more abundant IFN-γ transcripts when compared to control skin. Laser capture microdissection and immunohistology localized most IFN-γ-producing T cells to the tumor stroma. Reduced MART-1 expression was frequently observed in adjacent tumor cells. Consequently, IFN-γ may enhance inflammatory responses yet hamper effective recognition of melanoma cells. PMID:11839572

  3. Reduced Expression of FADS1 Predicts Worse Prognosis in Non-Small-Cell Lung Cancer

    PubMed Central

    Wang, Dong; Lin, Yan; Gao, Bei; Yan, Shumei; Wu, Huini; Li, Yong; Wu, Qiuliang; Wei, Yucheng

    2016-01-01

    Objective: Fatty acid desaturase 1 is a member of the fatty acid desaturase, which is related to a number of diseases. However, its role in cancers remains unclear. This study was to explore the clinical importance of FADS1 expression in non-small-cell lung cancer (NSCLC). Materials and Methods: Immunochemistry was used to evaluate FADS1 expressions in 216 paraffin-embedded specimens. The expression of FADS1 was divided into high and low groups. The clinical and prognostic significance of FADS1 expression was analyzed statistically by Kaplan-Meier estimate and Cox regression model. Results: FADS1 overexpressed in normal bronchial mucosa compared with non-small-cell lung cancer. Reduced FADS1 expression was associated with tumor size (P=0.023) and histological grade (P<0.0001). Patients with lower expression of FADS1 had shorter overall survival and disease free survival (P=0.001 and P=0.002). Multivariate analysis showed FADS1 expression was an independent prognostic factor in NSCLC (P=0.011). Conclusion: Reduced expression of FADS1 suggests pessimistic prognosis for NSCLC patients. Further studies are warranted. PMID:27390597

  4. Increased NY-ESO-1 expression and reduced infiltrating CD3+ T cells in cutaneous melanoma.

    PubMed

    Giavina-Bianchi, Mara; Giavina-Bianchi, Pedro; Sotto, Mirian Nacagami; Muzikansky, Alona; Kalil, Jorge; Festa-Neto, Cyro; Duncan, Lyn M

    2015-01-01

    NY-ESO-1 is a cancer-testis antigen aberrantly expressed in melanomas, which may serve as a robust and specific target in immunotherapy. NY-ESO-1 antigen expression, tumor features, and the immune profile of tumor infiltrating lymphocytes were assessed in primary cutaneous melanoma. NY-ESO-1 protein was detected in 20% of invasive melanomas (16/79), rarely in in situ melanoma (1/10) and not in benign nevi (0/20). Marked intratumoral heterogeneity of NY-ESO-1 protein expression was observed. NY-ESO-1 expression was associated with increased primary tumor thickness (P = 0.007) and inversely correlated with superficial spreading melanoma (P < 0.02). NY-ESO-1 expression was also associated with reduced numbers and density of CD3+ tumor infiltrating lymphocytes (P = 0.017). When NY-ESO-1 protein was expressed, CD3+ T cells were less diffusely infiltrating the tumor and were more often arranged in small clusters (P = 0.010) or as isolated cells (P = 0.002) than in large clusters of more than five lymphocytes. No correlation of NY-ESO-1 expression with gender, age, tumor site, ulceration, lymph node sentinel status, or survival was observed. NY-ESO-1 expression in melanoma was associated with tumor progression, including increased tumor thickness, and with reduced tumor infiltrating lymphocytes. PMID:25954764

  5. Flumazenil decreases surface expression of α4β2δ GABAA receptors by increasing the rate of receptor internalization.

    PubMed

    Kuver, Aarti; Smith, Sheryl S

    2016-01-01

    Increases in expression of α4βδ GABAA receptors (GABARs), triggered by fluctuations in the neurosteroid THP (3α-OH-5α[β]-pregnan-20-one), are associated with changes in mood and cognition. We tested whether α4βδ trafficking and surface expression would be altered by in vitro exposure to flumazenil, a benzodiazepine ligand which reduces α4βδ expression in vivo. We first determined that flumazenil (100 nM-100 μM, IC50=∼1 μM) acted as a negative modulator, reducing GABA (10 μM)-gated current in the presence of 100 nM THP (to increase receptor efficacy), assessed with whole cell patch clamp recordings of recombinant α4β2δ expressed in HEK-293 cells. Surface expression of recombinant α4β2δ receptors was detected using a 3XFLAG reporter at the C-terminus of α4 (α4F) using confocal immunocytochemical techniques following 48 h exposure of cells to GABA (10 μM)+THP (100 nM). Flumazenil (10 μM) decreased surface expression of α4F by ∼60%, while increasing its intracellular accumulation, after 48 h. Reduced surface expression of α4β2δ after flumazenil treatment was confirmed by decreases in the current responses to 100 nM of the GABA agonist gaboxadol. Flumazenil-induced decreases in surface expression of α4β2δ were prevented by the dynamin blocker, dynasore, and by leupeptin, which blocks lysosomal enzymes, suggesting that flumazenil is acting to increase endocytosis and lysosomal degradation of the receptor. Flumazenil increased the rate of receptor removal from the cell surface by 2-fold, assessed using botulinum toxin B to block insertion of new receptors. These findings may suggest new therapeutic strategies for regulation of α4β2δ expression using flumazenil. PMID:26592470

  6. Reduced LIMK2 expression in colorectal cancer reflects its role in limiting stem cell proliferation

    PubMed Central

    Lourenço, Filipe C; Munro, June; Brown, Jennifer; Cordero, Julia; Stefanatos, Rhoda; Strathdee, Karen; Orange, Clare; Feller, Stephan M; Sansom, Owen J; Vidal, Marcos; Murray, Graeme I; Olson, Michael F

    2014-01-01

    Objective Colorectal cancer (CRC) is a major contributor to cancer mortality and morbidity. LIM kinase 2 (LIMK2) promotes tumour cell invasion and metastasis. The objectives of this study were to determine how LIMK2 expression is associated with CRC progression and patient outcome, and to use genetically modified Drosophila and mice to determine how LIMK2 deletion affects gastrointestinal stem cell regulation and tumour development. Design LIMK2 expression and activity were measured by immunostaining tumours from CRC-prone mice, human CRC cell lines and 650 human tumours. LIMK knockdown in Drosophila or Limk2 deletion in mice allowed for assessment of their contributions to gastrointestinal stem cell homeostasis and tumour development. Results LIMK2 expression was reduced in intestinal tumours of cancer-prone mice, as well as in human CRC cell lines and tumours. Reduced LIMK2 expression and substrate phosphorylation were associated with shorter patient survival. Genetic analysis in Drosophila midgut and intestinal epithelial cells isolated from genetically modified mice revealed a conserved role for LIMK2 in constraining gastrointestinal stem cell proliferation. Limk2 deletion increased colon tumour size in a colitis-associated colorectal mouse cancer model. Conclusions This study revealed that LIMK2 expression and activity progressively decrease with advancing stage, and supports the hypothesis that there is selective pressure for reduced LIMK2 expression in CRC to relieve negative constraints imposed upon gastrointestinal stem cells. PMID:23585469

  7. Increased caspase-3 expression and activity contribute to reduced CD3zeta expression in systemic lupus erythematosus T cells.

    PubMed

    Krishnan, Sandeep; Kiang, Juliann G; Fisher, Carolyn U; Nambiar, Madhusoodana P; Nguyen, Hang T; Kyttaris, Vasileios C; Chowdhury, Bhabadeb; Rus, Violeta; Tsokos, George C

    2005-09-01

    T cells isolated from patients with systemic lupus erythematosus (SLE) express low levels of CD3zeta-chain, a critical molecule involved in TCR-mediated signaling, but the involved mechanisms are not fully understood. In this study we examined caspase-3 as a candidate for cleaving CD3zeta in SLE T cells. We demonstrate that SLE T cells display increased expression and activity of caspase-3. Treatment of SLE T cells with the caspase-3 inhibitor Z-Asp-Glu-Val-Asp-FMK reduced proteolysis of CD3zeta and enhanced its expression. In addition, Z-Asp-Glu-Val-Asp-FMK treatment increased the association of CD3zeta with lipid rafts and simultaneously reversed the abnormal lipid raft preclustering, heightened TCR-induced calcium responses, and reduced the expression of FcRgamma-chain exclusively in SLE T cells. We conclude that caspase-3 inhibitors can normalize SLE T cell function by limiting the excessive digestion of CD3zeta-chain and suggest that such molecules can be considered in the treatment of this disease. PMID:16116236

  8. Reduced expression and prognostic implication of inhibitor of growth 4 in human osteosarcoma

    PubMed Central

    ZHAO, DAHANG; LIU, XIANGJIE; ZHANG, YUNGE; DING, ZHAOMING; DONG, FENG; XU, HONGWEI; WANG, BAOXIN; WANG, WENBO

    2016-01-01

    Osteosarcoma is the most prevalent type of primary malignant bone tumor. Inhibitor of growth 4 (ING4) has been demonstrated to function as a tumor suppressor through multiple pathways, and is its expression is understood to be suppressed or reduced in various malignancies. The present study aimed to investigate the expression of ING4 and to determine its prognostic value in osteosarcoma tissue. Formalin-fixed, paraffin-embedded tissue microarrays were analyzed, and contained 41 osteosarcoma specimens and 11 normal bone tissue specimens with duplicate cores. ING4 expression was evaluated by immunohistochemical staining. The association between ING4 expression in the osteosarcoma and normal bone tissues was analyzed, in addition to the association between ING4 expression and Enneking classification of the osteosarcoma tissues. A significant statistical difference was observed in the ING4 immunohistochemical staining score between the osteosarcoma and normal bone tissues (P<0.001). Furthermore, a significant negative correlation was detected between the ING4 immunohistochemical staining scores and the Enneking classification results of the 41 osteosarcoma tissues (P=0.002). Low expression of ING4 was observed in the osteosarcoma specimens, and this reduced expression of ING4 was negatively correlated with Enneking classification. Thus, the results of the present study indicate that ING4 may serve as a promising prognostic marker in osteosarcoma. PMID:27073567

  9. Reduced tissue osmolarity increases TRPV4 expression and pro-inflammatory cytokines in intervertebral disc cells.

    PubMed

    Walter, B A; Purmessur, D; Moon, A; Occhiogrosso, J; Laudier, D M; Hecht, A C; Iatridis, J C

    2016-01-01

    The mechanical behaviour and cellular metabolism of intervertebral discs (IVDs) and articular cartilage are strongly influenced by their proteoglycan content and associated osmotic properties. This osmotic environment is a biophysical signal that changes with disease and may contribute to the elevated matrix breakdown and altered biologic response to loading observed in IVD degeneration and osteoarthritis. This study tested the hypothesis that changes in osmo-sensation by the transient receptor potential vallinoid-4 (TRPV4) ion channel occur with disease and contribute to the inflammatory environment found during degeneration. Immunohistochemistry on bovine IVDs from an inflammatory organ culture model were used to investigate if TRPV4 is expressed in the IVD and how expression changes with degeneration. Western blot, live-cell calcium imaging, and qRT-PCR were used to investigate whether osmolarity changes or tumour necrosis factor α (TNFα) regulate TRPV4 expression, and how altered TRPV4 expression influences calcium signalling and pro-inflammatory cytokine expression. TRPV4 expression correlated with TNFα expression, and was increased when cultured in reduced medium osmolarity and unaltered with TNFα-stimulation. Increased TRPV4 expression increased the calcium flux following TRPV4 activation and increased interleukin-1β (IL-1β) and IL-6 gene expression in IVD cells. TRPV4 expression was qualitatively elevated in regions of aggrecan depletion in degenerated human IVDs. Collectively, results suggest that reduced tissue osmolarity, likely following proteoglycan degradation, can increase TRPV4 signalling and enhance pro-inflammatory cytokine production, suggesting changes in TRPV4 mediated osmo-sensation may contribute to the progressive matrix breakdown in disease. PMID:27434269

  10. Strongly reduced Si surface recombination by charge injection during etching in diluted HF/HNO3.

    PubMed

    Greil, Stefanie M; Schöpke, Andreas; Rappich, Jörg

    2012-08-27

    Herein, we investigate the behaviour of the surface recombination of light-induced charge carriers during the etching of Si in alkaline (KOH) and acidic etching solutions of HF/HNO(3)/CH(3)COOH (HNA) or HF/HNO(3)/H(3)PO(4) (HNP) at different concentration ratios of HF and HNO(3) by means of photoluminescence (PL) measurements. The surface recombination velocity is strongly reduced during the first stages of etching in HF/HNO(3)-containing solutions pointing to a interface well passivated by the etching process, where a positive surface charge is induced by hole injection from NO-related surface species into the Si near-surface region (back surface field effect). This injected charge leads to a change in band bending by about 150 mV that repulses the light-induced charge carriers from the surface and therefore enhances the photoluminescence intensity, since non-radiative surface recombination is reduced. PMID:22761060

  11. ASIC2 Subunits Facilitate Expression at the Cell Surface and Confer Regulation by PSD-95

    PubMed Central

    Harding, Anne Marie S.; Kusama, Nobuyoshi; Hattori, Tomonori; Gautam, Mamta; Benson, Christopher J.

    2014-01-01

    Acid-sensing ion channels (ASICs) are Na+ channels activated by changes in pH within the peripheral and central nervous systems. Several different isoforms of ASICs combine to form trimeric channels, and their properties are determined by their subunit composition. ASIC2 subunits are widely expressed throughout the brain, where they heteromultimerize with their partnering subunit, ASIC1a. However, ASIC2 contributes little to the pH sensitivity of the channels, and so its function is not well understood. We found that ASIC2 increased cell surface levels of the channel when it is coexpressed with ASIC1a, and genetic deletion of ASIC2 reduced acid-evoked current amplitude in mouse hippocampal neurons. Additionally, ASIC2a interacted with the neuronal synaptic scaffolding protein PSD-95, and PSD-95 reduced cell surface expression and current amplitude in ASICs that contain ASIC2a. Overexpression of PSD-95 also reduced acid-evoked current amplitude in hippocampal neurons. This result was dependent upon ASIC2 since the effect of PSD-95 was abolished in ASIC2−/− neurons. These results lend support to an emerging role of ASIC2 in the targeting of ASICs to surface membranes, and allows for interaction with PSD-95 to regulate these processes. PMID:24699665

  12. Modified expression of surface glyconjugates in stored human platelets

    SciTech Connect

    Dhar, A.; Ganguly, P.

    1987-05-01

    Platelets are anucleated cells which play an important part in blood coagulation and thrombosis. These cells may be stored in the blood bank for only 4/5 days. In order to improve the storage of platelets, it is essential to first understand the changes in these cells due to storage. In this work, human platelets were stored in autologous plasma at 4/sup 0/ or 22/sup 0/ and their surface changes were monitored with three lectins - wheat germ afflutinin (WGA), concanavalin A (Con A) and lentil lectin (LL). Blood was drawn from healthy donors and platelet rich plasma (PRP) was collected by slow speed centrifugation. Platelets stored at either temperature for different times showed increased sensitivity to agglutination by WGA after 34-48 hrs. Lectins, Con A and LL, which were not agglutinating to fresh platelets readily caused agglutination after 48-72 hrs. The platelets stored for 25 hrs or longer period were insensitive to thrombin but showed enhanced aggregation with WGA. Labelling of surface glycoconjugates of stored platelets with /sup 3/H-boro-hydride revealed progressive loss of a glycoprotein of Mr 150,000 (GPIb infinity) together with the appearance of components of Mr 69,000; Mr 60,000; Mr 25,000. New high molecular weight glycoproteins were also detected only in stored platelets. The author studies clearly indicate that modification or altered expression of platelets surface glycoproteins may be one factor of storage related dysfunction of platelets.

  13. Reduced expression of Ca2+-regulating proteins in the upper gastrointestinal tract of patients with achalasia

    PubMed Central

    Fischer, Harald; Fischer, Judith; Boknik, Peter; Gergs, Ulrich; Schmitz, Wilhelm; Domschke, Wolfram; Konturek, Jan W; Neumann, Joachim

    2006-01-01

    AIM: To compare expression of Ca2+-regulating proteins in upper gastrointestinal (GI) tract of achalasia patients and healthy volunteers and to elucidate their role in achalasia. METHODS: Sarcoplasmic reticulum Ca2+ ATPase (SERCA) isoforms 2a and 2b, phospholamban (PLB), calsequestrin (CSQ), and calreticulin (CRT) were assessed by quantitative Western blotting in esophagus and heart of rats, rabbits, and humans. Furthermore, expression profiles of these proteins in biopsies of lower esophageal sphincter and esophagus from patients with achalasia and healthy volunteers were analyzed. RESULTS: SERCA 2a protein expression was much higher in human heart (cardiac ventricle) compared to esophagus. However, SERCA 2b was expressed predominantly in the esophagus. The highest CRT expression was noted in the human esophagus, while PLB, although highly expressed in the heart, was below our detection limit in upper GI tissue. Compared to healthy controls, CSQ and CRT expression in lower esophageal sphincter and distal esophageal body were significantly reduced in patients with achalasia (P < 0.05). CONCLUSION: PLB in the human esophagus might be of lesser importance for regulation of SERCA than in heart. Lower expression of Ca2+ storage proteins (CSQ and CRT) might contribute to increased lower esophageal sphincter pressure in achalasia, possibly by increasing free intracellular Ca2+. PMID:17009399

  14. An Acceptance-Based Psychoeducation Intervention to Reduce Expressed Emotion in Relatives of Bipolar Patients

    ERIC Educational Resources Information Center

    Eisner, Lori R.; Johnson, Sheri L.

    2008-01-01

    Expressed emotion (EE) is a robust predictor of outcome in bipolar disorder. Despite decades of research, interventions to reduce EE levels have had only modest effects. This study used an expanded model of EE to develop an intervention. Research has demonstrated a strong link between attributions and EE in families of patients with psychiatric…

  15. GEC-targeted HO-1 expression reduces proteinuria in glomerular immune injury.

    PubMed

    Duann, Pu; Lianos, Elias A

    2009-09-01

    Induction of heme oxygenase (HO)-1 is a key defense mechanism against oxidative stress. Compared with tubules, glomeruli are refractory to HO-1 upregulation in response to injury. This can be a disadvantage as it may be associated with insufficient production of cytoprotective heme-degradation metabolites. We, therefore, explored whether 1) targeted HO-1 expression can be achieved in glomeruli without altering their physiological integrity and 2) this expression reduces proteinuria in immune injury induced by an anti-glomerular basement membrane (GBM) antibody (Ab). We employed a 4.125-kb fragment of a mouse nephrin promoter downstream to which a FLAG-tagged hHO-1 cDNA sequence was inserted and subsequently generated transgenic mice from the FVB/N parental strain. There was a 16-fold higher transgene expression in the kidney than nonspecific background (liver) while the transprotein immunolocalized in glomerular epithelial cells (GEC). There was no change in urinary protein excretion, indicating that GEC-targeted HO-1 expression had no effect on glomerular protein permeability. Urinary protein excretion in transgenic mice with anti-GBM Ab injury (days 3 and 6) was significantly lower compared with wild-type controls. There was no significant change in renal expression levels of profibrotic (TGF-beta1) or anti-inflammatory (IL-10) cytokines in transgenic mice with anti-GBM Ab injury. These observations indicate that GEC-targeted HO-1 expression does not alter glomerular physiological integrity and reduces proteinuria in glomerular immune injury. PMID:19587144

  16. Association of reduced Connexin 43 expression with retinal vascular lesions in human diabetic retinopathy.

    PubMed

    Tien, Thomas; Muto, Tetsuya; Zhang, Joyce; Sohn, Elliott H; Mullins, Robert F; Roy, Sayon

    2016-05-01

    Connexin 43 (Cx43) downregulation promotes apoptosis in retinal vascular cells of diabetic animal models; however, its relevance to human diabetic retinopathy has not been established. In this study, we investigated whether diabetes alters Cx43 expression and promotes retinal vascular lesions in human retinas. Diabetic human eyes (aged 64-94 years) and non-diabetic human eyes (aged 61-90 years) were analyzed in this study. Retinal protein samples and retinal capillary networks were assessed for Cx43 level by Western blot (WB) analysis and immunostaining. In parallel, retinal capillary networks were stained with hematoxylin and periodic acid Schiff to determine the extent of pericyte loss (PL) and acellular capillaries (AC) in these retinas. Cx43 protein expression was significantly reduced in the diabetic retinas compared to non-diabetic retinas as indicated by WB analysis (81 ± 11% of control). Additionally, a significant decrease in the number of Cx43 plaques per unit length of vessel was observed in the diabetic retinas compared to those of non-diabetic retinas (62 ± 10% of control; p < 0.005). Importantly, a strong inverse relationship was noted between Cx43 expression and the relative number of AC (r = -0.89; p < 0.0005), and between Cx43 expression and number of pericyte loss (r = -0.88; p < 0.0005). Overall, these results show that Cx43 expression is reduced in the human diabetic retinas and Cx43 reduction is associated with increased vascular cell death. These findings suggest that diabetes decreases retinal Cx43 expression and that the development of PL and AC is associated with reduced Cx43 expression in human diabetic retinopathy. PMID:26738943

  17. Screening of mRNA Chemical Modification to Maximize Protein Expression with Reduced Immunogenicity.

    PubMed

    Uchida, Satoshi; Kataoka, Kazunori; Itaka, Keiji

    2015-01-01

    Chemical modification of nucleosides in mRNA is an important technology to regulate the immunogenicity of mRNA. In this study, various previously reported mRNA formulations were evaluated by analyzing in vitro protein expression and immunogenicity in multiple cell lines. For the macrophage-derived cell line, RAW 264.7, modified mRNA tended to have reduced immunogenicity and increased protein expression compared to the unmodified mRNA. In contrast, in some cell types, such as hepatocellular carcinoma cells (HuH-7) and mouse embryonic fibroblasts (MEFs), protein expression was decreased by mRNA modification. Further analyses revealed that mRNA modifications decreased translation efficiency but increased nuclease stability. Thus, mRNA modification is likely to exert both positive and negative effects on the efficiency of protein expression in transfected cells and optimal mRNA formulation should be determined based on target cell types and transfection purposes. PMID:26213960

  18. Screening of mRNA Chemical Modification to Maximize Protein Expression with Reduced Immunogenicity

    PubMed Central

    Uchida, Satoshi; Kataoka, Kazunori; Itaka, Keiji

    2015-01-01

    Chemical modification of nucleosides in mRNA is an important technology to regulate the immunogenicity of mRNA. In this study, various previously reported mRNA formulations were evaluated by analyzing in vitro protein expression and immunogenicity in multiple cell lines. For the macrophage-derived cell line, RAW 264.7, modified mRNA tended to have reduced immunogenicity and increased protein expression compared to the unmodified mRNA. In contrast, in some cell types, such as hepatocellular carcinoma cells (HuH-7) and mouse embryonic fibroblasts (MEFs), protein expression was decreased by mRNA modification. Further analyses revealed that mRNA modifications decreased translation efficiency but increased nuclease stability. Thus, mRNA modification is likely to exert both positive and negative effects on the efficiency of protein expression in transfected cells and optimal mRNA formulation should be determined based on target cell types and transfection purposes. PMID:26213960

  19. Hepcidin bound to α2-macroglobulin reduces ferroportin-1 expression and enhances its activity at reducing serum iron levels.

    PubMed

    Huang, Michael Li-Hsuan; Austin, Christopher J D; Sari, Marie-Agnès; Rahmanto, Yohan Suryo; Ponka, Prem; Vyoral, Daniel; Richardson, Des R

    2013-08-30

    Hepcidin regulates iron metabolism by down-regulating ferroportin-1 (Fpn1). We demonstrated that hepcidin is complexed to the blood transport protein, α2-macroglobulin (α2M) (Peslova, G., Petrak, J., Kuzelova, K., Hrdy, I., Halada, P., Kuchel, P. W., Soe-Lin, S., Ponka, P., Sutak, R., Becker, E., Huang, M. L., Suryo Rahmanto, Y., Richardson, D. R., and Vyoral, D. (2009) Blood 113, 6225-6236). However, nothing is known about the mechanism of hepcidin binding to α2M or the effects of the α2M·hepcidin complex in vivo. We show that decreased Fpn1 expression can be mediated by hepcidin bound to native α2M and also, for the first time, hepcidin bound to methylamine-activated α2M (α2M-MA). Passage of high molecular weight α2M·hepcidin or α2M-MA·hepcidin complexes (≈725 kDa) through a Sephadex G-25 size exclusion column retained their ability to decrease Fpn1 expression. Further studies using ultrafiltration indicated that hepcidin binding to α2M and α2M-MA was labile, resulting in some release from the protein, and this may explain its urinary excretion. To determine whether α2M-MA·hepcidin is delivered to cells via the α2M receptor (Lrp1), we assessed α2M uptake and Fpn1 expression in Lrp1(-/-) and Lrp1(+/+) cells. Interestingly, α2M·hepcidin or α2M-MA·hepcidin demonstrated similar activities at decreasing Fpn1 expression in Lrp1(-/-) and Lrp1(+/+) cells, indicating that Lrp1 is not essential for Fpn1 regulation. In vivo, hepcidin bound to α2M or α2M-MA did not affect plasma clearance of α2M/α2M-MA. However, serum iron levels were reduced to a significantly greater extent in mice treated with α2M·hepcidin or α2M-MA·hepcidin relative to unbound hepcidin. This effect could be mediated by the ability of α2M or α2M-MA to retard kidney filtration of bound hepcidin, increasing its half-life. A model is proposed that suggests that unlike proteases, which are irreversibly bound to activated α2M, hepcidin remains labile and available to down

  20. Reduced expression of SRY-box containing gene 17 correlates with an unfavorable melanoma patient survival.

    PubMed

    Lu, Jing; Zhang, Guohong; Cheng, Yabin; Tang, Yun; Dong, Ziming; McElwee, Kevin J; Li, Gang

    2014-12-01

    SRY-box containing gene 17 (Sox17), a transcription factor, is considered as an antagonist to canonical Wnt/β‑catenin signaling in several types of malignant tumors. As the influence of Sox17 in the pathogenesis of human melanoma is still unknown, the investigation of Sox17 expression in melanoma is warranted and its prognostic value is of great interest. In the present study, Sox17 expression was examined in 525 cases of melanocytic lesions (33 common acquired nevi, 59 dysplastic nevi, 291 primary melanomas and 142 metastatic melanomas) at different stages by tissue microarray. The correlation of Sox17 expression with melanoma progression and its prognostic value in melanoma patients were examined. We also analyzed the correlation between Sox17 and cyclin-dependent kinase inhibitor p27 expression in 374 melanoma samples. The results showed that Sox17 expression was significantly decreased in primary and metastatic melanoma compared to common acquired nevi and dysplastic nevi (P=2.4x10-17). Furthermore, Sox17 expression was inversely correlated with American Joint Committee on Cancer stage (P=4.6x10-15), thickness (P=0.00004) and ulceration (P=0.03). Notably, reduced Sox17 expression was correlated with a poorer overall and disease-specific 5- and 10-year survival of the patients. Multivariate Cox regression analyses indicated that Sox17 is an independent prognostic marker for melanoma patients. Moreover, we found a significant positive correlation between Sox17 and p27 expression in melanoma biopsies; their concomitant expression was closely correlated with the survival of melanoma patients. Taken together, decreased Sox17 expression is correlated with melanoma progression, an unfavorable survival of melanoma patients and is an independent molecular prognostic factor for melanoma. PMID:25310020

  1. VIRUS ADSORPTION TO MINERAL SURFACES IS REDUCED BY MICROBIAL OVERGROWTH AND ORGANIC COATINGS

    EPA Science Inventory

    In experiments with strains of poliovirus, reovirus, echovirus and Coxsackievirus, overgrowth with exopolymer-forming bacteria reduced virus adsorption to mineral surfaces. Adsorption was improved when organic materials adsorbed to minerals were removed by low-temperature ashing....

  2. The influence of reduced oxygen availability on pathogenicity and gene expression in Mycobacterium tuberculosis.

    PubMed

    Bacon, Joanna; James, Brian W; Wernisch, Lorenz; Williams, Ann; Morley, Kim A; Hatch, Graham J; Mangan, Joseph A; Hinds, Jason; Stoker, Neil G; Butcher, Philip D; Marsh, Philip D

    2004-01-01

    We investigated how Mycobacterium tuberculosis responded to a reduced oxygen tension in terms of its pathogenicity and gene expression by growing cells under either aerobic or low-oxygen conditions in chemostat culture. The chemostat enabled us to control and vary the oxygen tension independently of other environmental parameters, so that true cause-and-effect relationships of reduced oxygen availability could be established. Cells grown under low oxygen were more pathogenic for guinea pigs than those grown aerobically. The effect of reduced oxygen on global gene expression was determined using DNA microarray. Spearman rank correlation confirmed that microarray expression profiles were highly reproducible between repeat cultures. Using microarray analysis we have identified genes that respond to a low-oxygen environment without the influence of other parameters such as nutrient depletion. Some of these genes appear to be involved in the biosynthesis of cell wall precursors and their induction may have contributed to increased infectivity in the guinea pig. This study has shown that a combination of chemostat culture and microarray presents a biologically robust and statistically reliable experimental approach for studying the effect of relevant and specific environmental stimuli on mycobacterial virulence and gene expression. PMID:15207490

  3. Shear stress reduces protease activated receptor-1 expression in human endothelial cells

    NASA Technical Reports Server (NTRS)

    Nguyen, K. T.; Eskin, S. G.; Patterson, C.; Runge, M. S.; McIntire, L. V.

    2001-01-01

    Shear stress has been shown to regulate several genes involved in the thrombotic and proliferative functions of endothelial cells. Thrombin receptor (protease-activated receptor-1: PAR-1) increases at sites of vascular injury, which suggests an important role for PAR-1 in vascular diseases. However, the effect of shear stress on PAR-1 expression has not been previously studied. This work investigates effects of shear stress on PAR-1 gene expression in both human umbilical vein endothelial cells (HUVECs) and microvascular endothelial cells (HMECs). Cells were exposed to different shear stresses using a parallel plate flow system. Northern blot and flow cytometry analysis showed that shear stress down-regulated PAR-1 messenger RNA (mRNA) and protein levels in both HUVECs and HMECs but with different thresholds. Furthermore, shear-reduced PAR-1 mRNA was due to a decrease of transcription rate, not increased mRNA degradation. Postshear stress release of endothelin-1 in response to thrombin was reduced in HUVECs and HMECs. Moreover, inhibitors of potential signaling pathways applied during shear stress indicated mediation of the shear-decreased PAR-1 expression by protein kinases. In conclusion, shear stress exposure reduces PAR-1 gene expression in HMECs and HUVECs through a mechanism dependent in part on protein kinases, leading to altered endothelial cell functional responses to thrombin.

  4. Hedgehog inhibition reduces angiogenesis by downregulation of tumoral VEGF-A expression in hepatocellular carcinoma

    PubMed Central

    Pinter, Matthias; Sieghart, Wolfgang; Schmid, Monika; Dauser, Bernhard; Prager, Gerald; Dienes, Hans Peter; Trauner, Michael

    2013-01-01

    Background Dysregulation and activation of Hedgehog (Hh) signalling may contribute to tumorigenesis, angiogenesis, and metastatic seeding in several solid tumours. Objective We investigated the impact of Hh inhibition on tumour growth and angiogenesis using in-vitro and in-vivo models of hepatocellular carcinoma (HCC). Methods The effect of the Hh pathway inhibitor GDC-0449 on tumour growth was investigated using an orthotopic rat model. Effects on angiogenesis were determined by immunohistochemical staining of von Willebrand factor antigen and by assessing the mRNA expression of several angiogenic factors. In vitro, HCC cell lines were treated with GDC-0449 and evaluated for viability and expression of vascular endothelial growth factor (VEGF). Endothelial cells were evaluated for viability, migration, and tube formation. Results In the orthotopic HCC model, GDC-0449 significantly decreased tumoral VEGF expression which was accompanied by a significant reduction of microvessel density and tumour growth. In HCC cells, GDC-0449 had no effect on cell growth but significantly reduced target gene regulation and VEGF expression while having no direct effect on endothelial cell viability, migration, and tube formation. Conclusions Hh inhibition with GDC-0449 downregulates tumoral VEGF production in vitro and reduces tumoral VEGF expression, angiogenesis, and tumour growth in an orthotopic HCC model. PMID:24917971

  5. A Complex Interaction Between Reduced Reelin Expression and Prenatal Organophosphate Exposure Alters Neuronal Cell Morphology

    PubMed Central

    Mullen, Brian R.; Ross, Brennan; Chou, Joan Wang; Khankan, Rana; Khialeeva, Elvira; Bui, Kimberly

    2016-01-01

    Genetic and environmental factors are both likely to contribute to neurodevelopmental disorders including schizophrenia, autism spectrum disorders, and major depressive disorders. Prior studies from our laboratory and others have demonstrated that the combinatorial effect of two factors—reduced expression of reelin protein and prenatal exposure to the organophosphate pesticide chlorpyrifos oxon—gives rise to acute biochemical effects and to morphological and behavioral phenotypes in adolescent and young adult mice. In the current study, we examine the consequences of these factors on reelin protein expression and neuronal cell morphology in adult mice. While the cell populations that express reelin in the adult brain appear unchanged in location and distribution, the levels of full length and cleaved reelin protein show persistent reductions following prenatal exposure to chlorpyrifos oxon. Cell positioning and organization in the hippocampus and cerebellum are largely normal in animals with either reduced reelin expression or prenatal exposure to chlorpyrifos oxon, but cellular complexity and dendritic spine organization is altered, with a skewed distribution of immature dendritic spines in adult animals. Paradoxically, combinatorial exposure to both factors appears to generate a rescue of the dendritic spine phenotypes, similar to the mitigation of behavioral and morphological changes observed in our prior study. Together, our observations support an interaction between reelin expression and chlorpyrifos oxon exposure that is not simply additive, suggesting a complex interplay between genetic and environmental factors in regulating brain morphology. PMID:27364165

  6. A Complex Interaction Between Reduced Reelin Expression and Prenatal Organophosphate Exposure Alters Neuronal Cell Morphology.

    PubMed

    Mullen, Brian R; Ross, Brennan; Chou, Joan Wang; Khankan, Rana; Khialeeva, Elvira; Bui, Kimberly; Carpenter, Ellen M

    2016-06-01

    Genetic and environmental factors are both likely to contribute to neurodevelopmental disorders including schizophrenia, autism spectrum disorders, and major depressive disorders. Prior studies from our laboratory and others have demonstrated that the combinatorial effect of two factors-reduced expression of reelin protein and prenatal exposure to the organophosphate pesticide chlorpyrifos oxon-gives rise to acute biochemical effects and to morphological and behavioral phenotypes in adolescent and young adult mice. In the current study, we examine the consequences of these factors on reelin protein expression and neuronal cell morphology in adult mice. While the cell populations that express reelin in the adult brain appear unchanged in location and distribution, the levels of full length and cleaved reelin protein show persistent reductions following prenatal exposure to chlorpyrifos oxon. Cell positioning and organization in the hippocampus and cerebellum are largely normal in animals with either reduced reelin expression or prenatal exposure to chlorpyrifos oxon, but cellular complexity and dendritic spine organization is altered, with a skewed distribution of immature dendritic spines in adult animals. Paradoxically, combinatorial exposure to both factors appears to generate a rescue of the dendritic spine phenotypes, similar to the mitigation of behavioral and morphological changes observed in our prior study. Together, our observations support an interaction between reelin expression and chlorpyrifos oxon exposure that is not simply additive, suggesting a complex interplay between genetic and environmental factors in regulating brain morphology. PMID:27364165

  7. Reduced WIF-1 expression stimulates skin hyperpigmentation in patients with melasma.

    PubMed

    Kim, Ji-Young; Lee, Tae-Ryong; Lee, Ai-Young

    2013-01-01

    The expression of Wnt inhibitory factor-1 (WIF-1) gene, which was detected by a microarray analysis of hyperpigmented and normally pigmented skin sets of melasma patients, was significantly reduced in the hyperpigmented skin from melasma patients, but not in healthy controls, regardless of UV irradiation. Wnt signals regulate skin pigmentation; however, WIF-1 is expressed in cultured skin keratinocytes and fibroblasts, but not in melanocytes. Therefore, we examined whether WIF-1 knockdown in neighboring keratinocytes and fibroblasts plays a role in melasma. Additionally, the effect of WIF-1 overexpression on the amelioration of hyperpigmentation was examined. WIF-1 knockdown, either in fibroblasts or in keratinocytes, significantly stimulated tyrosinase expression and melanosome transfer, whereas melanocytes with WIF-1 overexpression significantly reduced those parameters. The WIF-1 knockdown decreased glycogen synthase kinase-3β (GSK-3β), β-catenin, and NFATc2 (nuclear factor of activated T cells, cytoplasmic, calcineurin-dependent 2) phosphorylation and increased microphthalmia-associated transcription factor (MITF) expression as in melanocytes with Wnt-1 overexpression, whereas the WIF-1 overexpression reversed the results. Expression of Wnts, both canonical and noncanonical, was increased in the hyperpigmented skin of melasma patients. Collectively, WIF-1 downregulation, which may occur in epidermal keratinocytes and in dermal fibroblasts, is involved in melasma development because of the stimulation of melanogenesis and melanosome transfer through upregulation of the canonical and the noncanonical Wnt signaling pathway. PMID:22951732

  8. Reduced DOCK4 expression leads to erythroid dysplasia in myelodysplastic syndromes

    PubMed Central

    Sundaravel, Sriram; Duggan, Ryan; Bhagat, Tushar; Ebenezer, David L.; Liu, Hui; Yu, Yiting; Bartenstein, Matthias; Unnikrishnan, Madhu; Karmakar, Subhradip; Liu, Ting-Chun; Torregroza, Ingrid; Quenon, Thomas; Anastasi, John; McGraw, Kathy L.; Pellagatti, Andrea; Boultwood, Jacqueline; Yajnik, Vijay; Artz, Andrew; Le Beau, Michelle M.; Steidl, Ulrich; List, Alan F.; Evans, Todd; Verma, Amit; Wickrema, Amittha

    2015-01-01

    Anemia is the predominant clinical manifestation of myelodysplastic syndromes (MDS). Loss or deletion of chromosome 7 is commonly seen in MDS and leads to a poor prognosis. However, the identity of functionally relevant, dysplasia-causing, genes on 7q remains unclear. Dedicator of cytokinesis 4 (DOCK4) is a GTPase exchange factor, and its gene maps to the commonly deleted 7q region. We demonstrate that DOCK4 is underexpressed in MDS bone marrow samples and that the reduced expression is associated with decreased overall survival in patients. We show that depletion of DOCK4 levels leads to erythroid cells with dysplastic morphology both in vivo and in vitro. We established a novel single-cell assay to quantify disrupted F-actin filament network in erythroblasts and demonstrate that reduced expression of DOCK4 leads to disruption of the actin filaments, resulting in erythroid dysplasia that phenocopies the red blood cell (RBC) defects seen in samples from MDS patients. Reexpression of DOCK4 in −7q MDS patient erythroblasts resulted in significant erythropoietic improvements. Mechanisms underlying F-actin disruption revealed that DOCK4 knockdown reduces ras-related C3 botulinum toxin substrate 1 (RAC1) GTPase activation, leading to increased phosphorylation of the actin-stabilizing protein ADDUCIN in MDS samples. These data identify DOCK4 as a putative 7q gene whose reduced expression can lead to erythroid dysplasia. PMID:26578796

  9. Reduced DOCK4 expression leads to erythroid dysplasia in myelodysplastic syndromes.

    PubMed

    Sundaravel, Sriram; Duggan, Ryan; Bhagat, Tushar; Ebenezer, David L; Liu, Hui; Yu, Yiting; Bartenstein, Matthias; Unnikrishnan, Madhu; Karmakar, Subhradip; Liu, Ting-Chun; Torregroza, Ingrid; Quenon, Thomas; Anastasi, John; McGraw, Kathy L; Pellagatti, Andrea; Boultwood, Jacqueline; Yajnik, Vijay; Artz, Andrew; Le Beau, Michelle M; Steidl, Ulrich; List, Alan F; Evans, Todd; Verma, Amit; Wickrema, Amittha

    2015-11-17

    Anemia is the predominant clinical manifestation of myelodysplastic syndromes (MDS). Loss or deletion of chromosome 7 is commonly seen in MDS and leads to a poor prognosis. However, the identity of functionally relevant, dysplasia-causing, genes on 7q remains unclear. Dedicator of cytokinesis 4 (DOCK4) is a GTPase exchange factor, and its gene maps to the commonly deleted 7q region. We demonstrate that DOCK4 is underexpressed in MDS bone marrow samples and that the reduced expression is associated with decreased overall survival in patients. We show that depletion of DOCK4 levels leads to erythroid cells with dysplastic morphology both in vivo and in vitro. We established a novel single-cell assay to quantify disrupted F-actin filament network in erythroblasts and demonstrate that reduced expression of DOCK4 leads to disruption of the actin filaments, resulting in erythroid dysplasia that phenocopies the red blood cell (RBC) defects seen in samples from MDS patients. Reexpression of DOCK4 in -7q MDS patient erythroblasts resulted in significant erythropoietic improvements. Mechanisms underlying F-actin disruption revealed that DOCK4 knockdown reduces ras-related C3 botulinum toxin substrate 1 (RAC1) GTPase activation, leading to increased phosphorylation of the actin-stabilizing protein ADDUCIN in MDS samples. These data identify DOCK4 as a putative 7q gene whose reduced expression can lead to erythroid dysplasia. PMID:26578796

  10. Methamphetamine reduces expression of caveolin-1 in the dorsal striatum: Implication for dysregulation of neuronal function.

    PubMed

    Somkuwar, Sucharita S; Fannon, McKenzie J; Head, Brian P; Mandyam, Chitra D

    2016-07-22

    Role of striatal dopamine D1 receptors (D1Rs) in methamphetamine (Meth) taking and seeking is recognized from contingent Meth self-administration studies. For example, Meth increases levels of D1Rs in the dorsal striatum in animal models of Meth addiction, and blockade of striatal D1Rs decreased responding for Meth and reduced Meth priming-induced drug seeking. However, the mechanism underlying enhanced expression of striatal D1Rs in animals self-administering Meth is unknown and is hypothesized to involve maladaptive intracellular signal transduction mechanism via hyperphosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). D1Rs are predominantly localized to detergent-resistant membrane/lipid raft fractions (MLR fraction), and in vitro studies indicate that D1R signaling and recycling is regulated by the MLR-resident protein caveolin-1 (Cav-1), in an endocytotic-dependent manner. Notably, expression of Cav-1 is inversely regulated by ERK1/2 activation, suggesting a signaling interplay among D1Rs, ERK1/2 and Cav-1. We therefore evaluated the effects of extended access Meth self-administration on expression of striatal D1Rs, activated ERK1/2 and Cav-1. We first report that Cav-1 is heavily expressed in neurons located in the dorsal striatum. We also report that extended access Meth produces compulsive-like unregulated intake of the drug, and these behavioral outcomes are associated with enhanced expression of D1Rs, increased activity of ERK1/2, and reduced Cav-1 expression in the dorsal striatum. These data suggest a possible cellular mechanism that involves Cav-1 regulation of D1R expression in response to escalated Meth intake, and how this response of altered D1Rs and enhanced ERK1/2 activation to Meth self-administration contributes to contingent-related processes such as addiction. PMID:27138644

  11. Klotho expression is reduced in COPD airway epithelial cells: effects on inflammation and oxidant injury

    PubMed Central

    Gao, Wei; Yuan, Cheng; Zhang, Jingying; Li, Lingling; Yu, Like; Wiegman, Coen H.; Barnes, Peter J.; Adcock, Ian M.; Huang, Mao

    2015-01-01

    COPD (chronic obstructive pulmonary disease) is associated with sustained inflammation, excessive injury, and accelerated lung aging. Human Klotho (KL) is an anti-aging protein that protects cells against inflammation and damage. In the present study, we quantified KL expression in the lungs of COPD patients and in an ozone-induced mouse model of COPD, and investigated the mechanisms that control KL expression and function in the airways. KL distribution and levels in human and mouse airways were measured by immunohistochemistry and Western blotting. The effect of CSE (cigarette smoke extract) on KL expression was detected in human bronchial epithelial cells. Moreover, the effect of KL on CSE-mediated inflammation and hydrogen peroxide-induced cellular injury/apoptosis was determined using siRNAs. KL expression was decreased in the lungs of smokers and further reduced in patients with COPD. Similarly, 6 weeks of exposure to ozone decreased KL levels in airway epithelial cells. CSE and TNFα (tumour necrosis factor α) decreased KL expression and release from airway epithelial cells, which was associated with enhanced pro-inflammatory cytokine expression. Moreover, KL depletion increased cell sensitivity to cigarette smoke-induced inflammation and oxidative stress-induced cell damage. These effects involved the NF-κB (nuclear factor κB), MAPK (mitogen-activated protein kinase) and Nrf2 (nuclear factor erythroid 2-related factor 2) pathways. Reduced KL expression in COPD airway epithelial cells was associated with increased oxidative stress, inflammation and apoptosis. These data provide new insights into the mechanisms associated with the accelerated lung aging in COPD development. PMID:26201096

  12. Betaine reduces the expression of inflammatory adipokines caused by hypoxia in human adipocytes.

    PubMed

    Olli, K; Lahtinen, S; Rautonen, N; Tiihonen, K

    2013-01-14

    Obesity is characterised by a state of chronic low-grade inflammation and the elevated circulating and tissue levels of inflammatory markers, including inflammation-related adipokines, released from white adipose tissue. The expression and release of these adipokines generally rises as the adipose tissue expands and hypoxic conditions start to develop within the tissue. Here, the effect of betaine, a trimethylglycine having a biological role as an osmolyte and a methyl donor, on the expression of inflammation-related markers was tested in human adipocytes under hypoxia. Differentiated adipocytes were cultivated under low (1 %) oxygen tension for 8-20 h. The expression of different adipokines, including IL-6, leptin, PPARγ, TNF-α and adiponectin, was measured by quantitative PCR by determining the relative mRNA level from the adipocytes. Hypoxia, in general, led to a decrease in the expression of PPARγ mRNA in human adipocytes, whereas the expression levels of leptin and IL-6 mRNA were substantially increased by hypoxia. The cultivation of adipocytes under hypoxia also led to a reduction in the expression of TNF-α mRNA. The results showed that hypoxia increased the relative quantification of leptin gene transcription, and that betaine (250 μmol/l) reduced this effect, caused by low oxygen conditions. Under hypoxia, betaine also reduced the mRNA level of the pro-inflammatory markers IL-6 and TNF-α. These results demonstrate that the extensive changes in the expression of inflammation-related adipokines in human adipocytes caused by hypoxia can be diminished by the presence of physiologically relevant concentrations of betaine. PMID:22424556

  13. Klotho expression is reduced in COPD airway epithelial cells: effects on inflammation and oxidant injury.

    PubMed

    Gao, Wei; Yuan, Cheng; Zhang, Jingying; Li, Lingling; Yu, Like; Wiegman, Coen H; Barnes, Peter J; Adcock, Ian M; Huang, Mao; Yao, Xin

    2015-12-01

    COPD (chronic obstructive pulmonary disease) is associated with sustained inflammation, excessive injury, and accelerated lung aging. Human Klotho (KL) is an anti-aging protein that protects cells against inflammation and damage. In the present study, we quantified KL expression in the lungs of COPD patients and in an ozone-induced mouse model of COPD, and investigated the mechanisms that control KL expression and function in the airways. KL distribution and levels in human and mouse airways were measured by immunohistochemistry and Western blotting. The effect of CSE (cigarette smoke extract) on KL expression was detected in human bronchial epithelial cells. Moreover, the effect of KL on CSE-mediated inflammation and hydrogen peroxide-induced cellular injury/apoptosis was determined using siRNAs. KL expression was decreased in the lungs of smokers and further reduced in patients with COPD. Similarly, 6 weeks of exposure to ozone decreased KL levels in airway epithelial cells. CSE and TNFα (tumour necrosis factor α) decreased KL expression and release from airway epithelial cells, which was associated with enhanced pro-inflammatory cytokine expression. Moreover, KL depletion increased cell sensitivity to cigarette smoke-induced inflammation and oxidative stress-induced cell damage. These effects involved the NF-κB (nuclear factor κB), MAPK (mitogen-activated protein kinase) and Nrf2 (nuclear factor erythroid 2-related factor 2) pathways. Reduced KL expression in COPD airway epithelial cells was associated with increased oxidative stress, inflammation and apoptosis. These data provide new insights into the mechanisms associated with the accelerated lung aging in COPD development. PMID:26201096

  14. USE OF NEGATIVE ARI IONIZATION FOR REDUCING BACTERIAL PATHOGENS AND SPORES ON STAINLESS STEEL SURFACES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of chemicals in food plant sanitation for removing and killing microorganisms could be reduced by the use of alternative non-chemical interventions. Negative air ionization is a new technology that has shown potential to effectively reduce airborne and surface microorganisms. Current studies...

  15. Brain SERT Expression of Male Rats Is Reduced by Aging and Increased by Testosterone Restitution

    PubMed Central

    Herrera-Pérez, José Jaime; Fernández-Guasti, Alonso; Martínez-Mota, Lucía

    2013-01-01

    In preclinical and clinical studies aging has been associated with a deteriorated response to antidepressant treatment. We hypothesize that such impairment is explained by an age-related decrease in brain serotonin transporter (SERT) expression associated with low testosterone (T) levels. The objectives of this study were to establish (1) if brain SERT expression is reduced by aging and (2) if the SERT expression in middle-aged rats is increased by T-restitution. Intact young rats (3–5 months) and gonad-intact middle-aged rats with or without T-restitution were used. The identification of the brain SERT expression was done by immunofluorescence in prefrontal cortex, lateral septum, hippocampus, and raphe nuclei. An age-dependent reduction of SERT expression was observed in all brain regions examined, while T-restitution recovered the SERT expression only in the dorsal raphe of middle-aged rats. This last action seems relevant since dorsal raphe plays an important role in the antidepressant action of selective serotonin reuptake inhibitors. All data suggest that this mechanism accounts for the T-replacement usefulness to improve the response to antidepressants in the aged population. PMID:26317087

  16. Expression of surface platelet receptors (CD62P and CD41/61) in horses with recurrent airway obstruction (RAO).

    PubMed

    Iwaszko-Simonik, Alicja; Niedzwiedz, Artur; Graczyk, Stanislaw; Slowikowska, Malwina; Pliszczak-Krol, Aleksandra

    2015-03-15

    Recurrent airway obstruction (RAO) is an allergic disease of horses similar to human asthma, which is characterized by airway inflammation and activation of neutrophils, lymphocytes and platelets. Platelet activation and an increase in circulating platelet-leukocyte aggregates may lead to airway remodeling. The aim of this study was to investigate platelet status in RAO-affected horses based on the platelet morphology and platelet surface expression of CD41/61 and CD62P. Ten RAO-affected horses and ten healthy horses were included in this study. Blood samples were obtained to determine the platelet count (PLT), mean platelet volume (MPV) and platelet large cell ratio (P-LCR). Expression of CD62P and CD41/61 was detected by flow cytometry on activated platelets. The median PLT was significantly reduced in horses with RAO compared to the controls. The MPV and the P-LCR values were significantly higher in RAO horses than controls. Expression of CD41/61 on platelets was increased in RAO horses, while CD62P expression was reduced. This study demonstrated the morphological changes in platelets and expression of platelet surface receptors. Despite the decrease of CD62P expression, the observed increased surface expression of CD41/61 on platelets in horses with RAO may contribute to the formation of platelet aggregates in their respiratory system. PMID:25665521

  17. Elimination of Kalrn Expression in POMC Cells Reduces Anxiety-Like Behavior and Contextual Fear Learning

    PubMed Central

    Mandela, Prashant; Yan, Yan; LaRese, Taylor; Eipper, Betty A.; Mains, Richard E.

    2014-01-01

    Kalirin, a Rho GDP/GTP exchange factor for Rac1 and RhoG, is known to play an essential role in the formation and maintenance of excitatory synapses and in the secretion of neuropeptides. Mice unable to express any of the isoforms of Kalrn in cells that produce POMC at any time during development (POMC cells) exhibited reduced anxiety-like behavior and reduced acquisition of passive avoidance behavior, along with sex-specific alteration in the corticosterone response to restraint stress. Strikingly, lack of Kalrn expression in POMC cells closely mimicked the effects of global Kalrn knockout on anxiety-like behavior and passive avoidance conditioning without causing the other deficits noted in Kalrn knockout mice. Our data suggest that deficits in excitatory inputs onto POMC neurons are responsible for the behavioral phenotypes observed. PMID:25014196

  18. Elimination of Kalrn expression in POMC cells reduces anxiety-like behavior and contextual fear learning.

    PubMed

    Mandela, Prashant; Yan, Yan; LaRese, Taylor; Eipper, Betty A; Mains, Richard E

    2014-07-01

    Kalirin, a Rho GDP/GTP exchange factor for Rac1 and RhoG, is known to play an essential role in the formation and maintenance of excitatory synapses and in the secretion of neuropeptides. Mice unable to express any of the isoforms of Kalrn in cells that produce POMC at any time during development (POMC cells) exhibited reduced anxiety-like behavior and reduced acquisition of passive avoidance behavior, along with sex-specific alteration in the corticosterone response to restraint stress. Strikingly, lack of Kalrn expression in POMC cells closely mimicked the effects of global Kalrn knockout on anxiety-like behavior and passive avoidance conditioning without causing the other deficits noted in Kalrn knockout mice. Our data suggest that deficits in excitatory inputs onto POMC neurons are responsible for the behavioral phenotypes observed. PMID:25014196

  19. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression.

    PubMed

    Liu, Xin-Hua; Yao, Shen; Qiao, Rui-Fang; Levine, Alice C; Kirschenbaum, Alexander; Pan, Jiangping; Wu, Yong; Qin, Weiping; Bauman, William A; Cardozo, Christopher P

    2011-10-14

    Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy. PMID:21945932

  20. Benzylglucosinolate Derived Isothiocyanate from Tropaeolum majus Reduces Gluconeogenic Gene and Protein Expression in Human Cells.

    PubMed

    Guzmán-Pérez, Valentina; Bumke-Vogt, Christiane; Schreiner, Monika; Mewis, Inga; Borchert, Andrea; Pfeiffer, Andreas F H

    2016-01-01

    Nasturtium (Tropaeolum majus L.) contains high concentrations of benzylglcosinolate. We found that a hydrolysis product of benzyl glucosinolate-the benzyl isothiocyanate (BITC)-modulates the intracellular localization of the transcription factor Forkhead box O 1 (FOXO1). FoxO transcription factors can antagonize insulin effects and trigger a variety of cellular processes involved in tumor suppression, longevity, development and metabolism. The current study evaluated the ability of BITC-extracted as intact glucosinolate from nasturtium and hydrolyzed with myrosinase-to modulate i) the insulin-signaling pathway, ii) the intracellular localization of FOXO1 and, iii) the expression of proteins involved in gluconeogenesis, antioxidant response and detoxification. Stably transfected human osteosarcoma cells (U-2 OS) with constitutive expression of FOXO1 protein labeled with GFP (green fluorescent protein) were used to evaluate the effect of BITC on FOXO1. Human hepatoma HepG2 cell cultures were selected to evaluate the effect on gluconeogenic, antioxidant and detoxification genes and protein expression. BITC reduced the phosphorylation of protein kinase B (AKT/PKB) and FOXO1; promoted FOXO1 translocation from cytoplasm into the nucleus antagonizing the insulin effect; was able to down-regulate the gene and protein expression of gluconeogenic enzymes; and induced the gene expression of antioxidant and detoxification enzymes. Knockdown analyses with specific siRNAs showed that the expression of gluconeogenic genes was dependent on nuclear factor (erythroid derived)-like2 (NRF2) and independent of FOXO1, AKT and NAD-dependent deacetylase sirtuin-1 (SIRT1). The current study provides evidence that BITC might have a role in type 2 diabetes T2D by reducing hepatic glucose production and increasing antioxidant resistance. PMID:27622707

  1. Abrogation of Junctional Adhesion Molecule-A Expression Induces Cell Apoptosis and Reduces Breast Cancer Progression

    PubMed Central

    Murakami, Masato; Giampietro, Costanza; Giannotta, Monica; Corada, Monica; Torselli, Ilaria; Orsenigo, Fabrizio; Cocito, Andrea; d'Ario, Giovanni; Mazzarol, Giovanni; Confalonieri, Stefano; Di Fiore, Pier Paolo; Dejana, Elisabetta

    2011-01-01

    Intercellular junctions promote homotypic cell to cell adhesion and transfer intracellular signals which control cell growth and apoptosis. Junctional adhesion molecule-A (JAM-A) is a transmembrane immunoglobulin located at tight junctions of normal epithelial cells of mammary ducts and glands. In the present paper we show that JAM-A acts as a survival factor for mammary carcinoma cells. JAM-A null mice expressing Polyoma Middle T under MMTV promoter develop significantly smaller mammary tumors than JAM-A positive mice. Angiogenesis and inflammatory or immune infiltrate were not statistically modified in absence of JAM-A but tumor cell apoptosis was significantly increased. Tumor cells isolated from JAM-A null mice or 4T1 cells incubated with JAM-A blocking antibodies showed reduced growth and increased apoptosis which paralleled altered junctional architecture and adhesive function. In a breast cancer clinical data set, tissue microarray data show that JAM-A expression correlates with poor prognosis. Gene expression analysis of mouse tumor samples showed a correlation between genes enriched in human G3 tumors and genes over expressed in JAM-A +/+ mammary tumors. Conversely, genes enriched in G1 human tumors correlate with genes overexpressed in JAM-A−/− tumors. We conclude that down regulation of JAM-A reduces tumor aggressive behavior by increasing cell susceptibility to apoptosis. JAM-A may be considered a negative prognostic factor and a potential therapeutic target. PMID:21695058

  2. Reduced keratin expression in colorectal neoplasia and associated fields is reversible by diet and resection

    PubMed Central

    Evans, Caroline A; Rosser, Ria; Waby, Jennifer S; Noirel, Josselin; Lai, Daphne; Wright, Phillip C; Williams, Elizabeth A; Riley, Stuart A; Bury, Jonathan P; Corfe, Bernard M

    2015-01-01

    Background Patients with adenomatous colonic polyps are at increased risk of developing further polyps suggesting field-wide alterations in cancer predisposition. The current study aimed to identify molecular alterations in the normal mucosa in the proximity of adenomatous polyps and to assess the modulating effect of butyrate, a chemopreventive compound produced by fermentation of dietary residues. Methods A cross-sectional study was undertaken in patients with adenomatous polyps: biopsy samples were taken from the adenoma, and from macroscopically normal mucosa on the contralateral wall to the adenoma and from the mid-sigmoid colon. In normal subjects biopsies were taken from the mid-sigmoid colon. Biopsies were frozen for proteomic analysis or formalin-fixed for immunohistochemistry. Proteomic analysis was undertaken using iTRAQ workflows followed by bioinformatics analyses. A second dietary fibre intervention study arm used the same endpoints and sampling strategy at the beginning and end of a high-fibre intervention. Results Key findings were that keratins 8, 18 and 19 were reduced in expression level with progressive proximity to the lesion. Lesional tissue exhibited multiple K8 immunoreactive bands and overall reduced levels of keratin. Biopsies from normal subjects with low faecal butyrate also showed depressed keratin expression. Resection of the lesion and elevation of dietary fibre intake both appeared to restore keratin expression level. Conclusion Changes in keratin expression associate with progression towards neoplasia, but remain modifiable risk factors. Dietary strategies may improve secondary chemoprevention. Trial registration number ISRCTN90852168. PMID:26462274

  3. Bisdemethoxycurcumin inhibits ovarian cancer via reducing oxidative stress mediated MMPs expressions

    PubMed Central

    Pei, Haifeng; Yang, Yi; Cui, Lin; Yang, Jiong; Li, Xiuchuan; Yang, Yongjian; Duan, Haixia

    2016-01-01

    As one main active compound of curcuminoids, Bisdemethoxycurcumin (BDMC) possesses several biological activities, such as anti-inflammation and anti-cancer activities. However, the detailed mechanism of BDMC’s anti-metastasis activity in ovarian cancer has not been clearly elucidated yet. In the present study, cell proliferation, wound healing motility, cell adhesion and invasion with or without BDMC were determined. In addition, western blot was used to examine proteins expressions. The lucigenin-enhanced luminescence was introduced to assess cellular oxidative stress. The luciferase reporter gene assay was introduced to evaluate the transcriptional activity of NF-κB. Finally, BDMC significantly inhibited the adhesion, migration, invasion and metastasis of SKOV-3 cells. Moreover, BDMC inhibited expressions of several degradation-associated proteins, such as matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), CD147, urokinase plasminogen activator (uPA), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), whereas increased expression of tissue inhibitor of metalloproteinase-1 (TIMP-1), in a dose-dependent manner. In addition, BDMC reduced generation of cellular superoxide in a dose-dependent manner. Furthermore, BDMC inhibited the phosphorylation levels of NF-κB p65 and IκB-α, and consequently reduced NF-κB-driven luciferase expression. Collectively, BDMC serves as a therapeutic medicine to suppress ovarian cancer, perhaps via inhibiting cellular oxidative stress and subsequently inactivating NF-κB pathway. PMID:27349797

  4. Gentiana scabra Reduces SR-A Expression and Oxidized-LDL Uptake in Human Macrophages

    PubMed Central

    Lin, Chin-Sheng; Liu, Pang-Yen; Lian, Chen-Hao; Lin, Ching-Heng; Lai, Jenn-Haung; Ho, Ling-Jun; Yang, Shih-Ping; Cheng, Shu-Meng

    2016-01-01

    Background Macrophages can imbibe low-density lipoprotein (LDL) through scavenger receptors to become foam cells, which is critical in the initiation and progression of atherosclerosis. Mounting evidence suggests that the anti-inflammatory nature of Chinese herbs have the capacity to halt the complex mechanisms underlying atherosclerosis. This study examined the effects of Chinese herbs on foam cell formation. Methods Chinese herbs were obtained from the Sun Ten pharmaceutic company. Using oxidized LDL (OxLDL) uptake and a cell toxicity assay, we screened more than 30 types of Chinese herbs. Western blotting was used to determine expressions of scavenger receptors (SRs) and extracellular-signal-regulated kinase (ERK) activities. Results We found that Gentiana scabra reduced oxidized LDL uptake effectively in THP-1 macrophages (p < 0.05 vs. OxLDL treated control). Moreover, treatment with Gentiana scabra in THP-1 macrophages resulted in decreased expression of scavenger receptor- A (SR-A) (p < 0.05 vs. control). Molecular investigation revealed that Gentiana scabra inhibited SR-A protein expression, possibly by regulating ERK signaling pathways (p < 0.05 vs. control). Conclusions By regulating SR-A expression, Gentiana scabra reduced oxidized LDL uptake in human macrophages. These results support the potential use of Gentiana scabra in treating atherosclerosis. PMID:27471359

  5. Improved chemical and electrochemical stability of perovskite oxides with less reducible cations at the surface.

    PubMed

    Tsvetkov, Nikolai; Lu, Qiyang; Sun, Lixin; Crumlin, Ethan J; Yildiz, Bilge

    2016-09-01

    Segregation and phase separation of aliovalent dopants on perovskite oxide (ABO3) surfaces are detrimental to the performance of energy conversion systems such as solid oxide fuel/electrolysis cells and catalysts for thermochemical H2O and CO2 splitting. One key reason behind the instability of perovskite oxide surfaces is the electrostatic attraction of the negatively charged A-site dopants (for example, ) by the positively charged oxygen vacancies () enriched at the surface. Here we show that reducing the surface concentration improves the oxygen surface exchange kinetics and stability significantly, albeit contrary to the well-established understanding that surface oxygen vacancies facilitate reactions with O2 molecules. We take La0.8Sr0.2CoO3 (LSC) as a model perovskite oxide, and modify its surface with additive cations that are more and less reducible than Co on the B-site of LSC. By using ambient-pressure X-ray absorption and photoelectron spectroscopy, we proved that the dominant role of the less reducible cations is to suppress the enrichment and phase separation of Sr while reducing the concentration of and making the LSC more oxidized at its surface. Consequently, we found that these less reducible cations significantly improve stability, with up to 30 times faster oxygen exchange kinetics after 54 h in air at 530 °C achieved by Hf addition onto LSC. Finally, the results revealed a 'volcano' relation between the oxygen exchange kinetics and the oxygen vacancy formation enthalpy of the binary oxides of the additive cations. This volcano relation highlights the existence of an optimum surface oxygen vacancy concentration that balances the gain in oxygen exchange kinetics and the chemical stability loss. PMID:27295099

  6. Reducing the In2O3(111) Surface Results in Ordered Indium Adatoms

    SciTech Connect

    Wagner, Margareta; Seiler, Steffen; Meyer, Bernd; Boatner, Lynn A; Schmid, M.; Diebold, U.

    2014-01-01

    The In2O3(111) surface can be transformed from an oxidized bulk termination to one that is covered by single In adatoms. As each adatom sits at one specific site within the surface unit cell they form a well-ordered (1 1) superstructure. Annealing at 500 C in O2 or in ultrahigh vacuum results in a fully reversible conversion between these two surface terminations; this transformation and intermediate stages were followed with Scanning Tunneling Microscopy (STM). Formation of this novel surface structure under reducing conditions is corroborated by Density Functional Theory (DFT). The reduced adatom-covered and the oxidized In2O3(111) surfaces are expected to exhibit different chemical and electronic properties, which can easily be exploited by the facile and reversible switching between the two terminations.

  7. Reduced gene expression levels after chronic exposure to high concentrations of air pollutants.

    PubMed

    Rossner, Pavel; Tulupova, Elena; Rossnerova, Andrea; Libalova, Helena; Honkova, Katerina; Gmuender, Hans; Pastorkova, Anna; Svecova, Vlasta; Topinka, Jan; Sram, Radim J

    2015-10-01

    We analyzed the ability of particulate matter (PM) and chemicals adsorbed onto it to induce diverse gene expression profiles in subjects living in two regions of the Czech Republic differing in levels and sources of the air pollution. A total of 312 samples from polluted Ostrava region and 154 control samples from Prague were collected in winter 2009, summer 2009 and winter 2010. The highest concentrations of air pollutants were detected in winter 2010 when the subjects were exposed to: PM of aerodynamic diameter <2.5μm (PM2.5) (70 vs. 44.9μg/m(3)); benzo[a]pyrene (9.02 vs. 2.56ng/m(3)) and benzene (10.2 vs. 5.5μg/m(3)) in Ostrava and Prague, respectively. Global gene expression analysis of total RNA extracted from leukocytes was performed using Illumina Expression BeadChips microarrays. The expression of selected genes was verified by quantitative real-time PCR (qRT-PCR). Gene expression profiles differed by locations and seasons. Despite lower concentrations of air pollutants a higher number of differentially expressed genes and affected KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways was found in subjects from Prague. In both locations immune response pathways were affected, in Prague also neurodegenerative diseases-related pathways. Over-representation of the latter pathways was associated with the exposure to PM2.5. The qRT-PCR analysis showed a significant decrease in expression of APEX, ATM, FAS, GSTM1, IL1B and RAD21 in subjects from Ostrava, in a comparison of winter 2010 and summer 2009. In Prague, an increase in gene expression was observed for GADD45A and PTGS2. In conclusion, high concentrations of pollutants in Ostrava were not associated with higher number of differentially expressed genes, affected KEGG pathways and expression levels of selected genes. This observation suggests that chronic exposure to air pollution may result in reduced gene expression response with possible negative health consequences. PMID:26298100

  8. Methoxychlor and fenvalerate induce neuronal death by reducing GluR2 expression.

    PubMed

    Umeda, Kanae; Kotake, Yaichiro; Miyara, Masatsugu; Ishida, Keishi; Sanoh, Seigo; Ohta, Shigeru

    2016-04-01

    GluR2, an α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor subunit, plays important roles in neuronal survival. We previously showed that exposure of cultured rat cortical neurons to several chemicals decreases GluR2 protein expression, leading to neuronal toxicity. Methoxychlor, the bis-p-methoxy derivative of dichlorodiphenyltrichloroethane, and fenvalerate, a synthetic pyrethroid chemical, have been used commercially as agricultural pesticides in several countries. In this study, we investigated the effects of long-term methoxychlor and fenvalerate exposure on neuronal glutamate receptors. Treatment of cultured rat cortical neurons with 1 or 10 µM methoxychlor and fenvalerate for 9 days selectively decreased GluR2 protein expression; the expression of other AMPA receptor subunits GluR1, GluR3, and GluR4 did not change under the same conditions. Importantly, the decreases in GluR2 protein expression were also observed on the cell surface membrane where AMPA receptors typically function. In addition, both chemicals decreased neuronal viability, which was blocked by pretreatment with 1-naphtylacetylspermine, an antagonist of GluR2-lacking AMPA receptors, and MK-801, an N-methyl-d-aspartate (NMDA) receptor antagonist. These results suggest that long-term exposure to methoxychlor and fenvalerate decreases GluR2 protein expression, leading to neuronal death via overactivation of GluR2-lacking AMPA and NMDA receptors. PMID:26961610

  9. Surface expressions of mantle upwellings: Expect the unexpected

    NASA Astrophysics Data System (ADS)

    Druken, K. A.; Kincaid, C. R.; Griffiths, R. W.

    2011-12-01

    Surface expressions of deep mantle upwellings are oftentimes complex and vary from highly simplified schematic models. We present results from a series of 3-D laboratory experiments that examine patterns of strain alignment within mantle upwellings under a variety of tectonic settings (e.g. mid-plate, spreading centers, subduction zones) and compare these to observations from seismic anisotropy studies. Laboratory experiments utilize a glucose working fluid with a temperature dependent density and viscosity. In the strain alignment cases, ~5 mm long synthetic paintbrush hairs, or "whiskers", are embedded within the fluid and used as passive markers for the local orientation of maximum finite strain. Contrary to the common expectation, results show that finite strain aligns tangent, not parallel, to the radial flow within plume heads. In cases where a plume rises under a moving plate or spreading center, strain markers are initially tangential and then evolve towards alignment with the shear flow. Within subduction settings, upwellings are so severely distorted by slab-driven flow that they appear seismically invisible in terms of anisotropy patterns.

  10. Increased Expression of the Diabetes Gene SOX4 Reduces Insulin Secretion by Impaired Fusion Pore Expansion.

    PubMed

    Collins, Stephan C; Do, Hyun Woong; Hastoy, Benoit; Hugill, Alison; Adam, Julie; Chibalina, Margarita V; Galvanovskis, Juris; Godazgar, Mahdieh; Lee, Sheena; Goldsworthy, Michelle; Salehi, Albert; Tarasov, Andrei I; Rosengren, Anders H; Cox, Roger; Rorsman, Patrik

    2016-07-01

    The transcription factor Sox4 has been proposed to underlie the increased type 2 diabetes risk linked to an intronic single nucleotide polymorphism in CDKAL1 In a mouse model expressing a mutant form of Sox4, glucose-induced insulin secretion is reduced by 40% despite normal intracellular Ca(2+) signaling and depolarization-evoked exocytosis. This paradox is explained by a fourfold increase in kiss-and-run exocytosis (as determined by single-granule exocytosis measurements) in which the fusion pore connecting the granule lumen to the exterior expands to a diameter of only 2 nm, which does not allow the exit of insulin. Microarray analysis indicated that this correlated with an increased expression of the exocytosis-regulating protein Stxbp6. In a large collection of human islet preparations (n = 63), STXBP6 expression and glucose-induced insulin secretion correlated positively and negatively with SOX4 expression, respectively. Overexpression of SOX4 in the human insulin-secreting cell EndoC-βH2 interfered with granule emptying and inhibited hormone release, the latter effect reversed by silencing STXBP6 These data suggest that increased SOX4 expression inhibits insulin secretion and increased diabetes risk by the upregulation of STXBP6 and an increase in kiss-and-run exocytosis at the expense of full fusion. We propose that pharmacological interventions promoting fusion pore expansion may be effective in diabetes therapy. PMID:26993066

  11. Increased expression of the diabetes gene SOX4 reduces insulin secretion by impaired fusion pore expansion

    PubMed Central

    Collins, Stephan C.; Do, Hyun Woong; Hastoy, Benoit; Hugill, Alison; Adam, Julie; Chibalina, Margarita V.; Galvanovskis, Juris; Godazgar, Mahdieh; Lee, Sheena; Goldsworthy, Michelle; Salehi, Albert; Tarasov, Andrei I.; Rosengren, Anders H.; Cox, Roger; Rorsman, Patrik

    2016-01-01

    The transcription factor Sox4 has been proposed to underlie the increased type-2 diabetes risk linked to an intronic SNP in CDKAL1. In a mouse model expressing a mutant form of Sox4, glucose-induced insulin secretion is reduced by 40% despite normal intracellular Ca2+ signalling and depolarization-evoked exocytosis. This paradox is explained by a 4-fold increase in kiss-and-run exocytosis (as determined by single-granule exocytosis measurements), in which the fusion pore connecting the granule lumen to the exterior only expands to a diameter of 2 nm that does not allow the exit of insulin. Microarray analysis indicated that this correlated with an increased expression of the exocytosis-regulating protein Stxbp6. In a large collection of human islet preparations (n=63), STXBP6 expression and GIIS correlated positively and negatively with SOX4 expression, respectively. Overexpression of SOX4 in the human insulin-secreting cell EndoC-βH2 interfered with granule emptying and inhibited hormone release, the latter effect was reversed by silencing of STXBP6. These data suggest that increased SOX4 expression inhibits insulin secretion and increased diabetes risk by upregulation of STXBP6 and an increase in kiss-and-run exocytosis at the expense of full fusion. We propose that pharmacological interventions promoting fusion pore expansion may be effective in diabetes therapy. PMID:26993066

  12. Reduced expression of TGF beta is associated with advanced disease in transitional cell carcinoma.

    PubMed Central

    Coombs, L. M.; Pigott, D. A.; Eydmann, M. E.; Proctor, A. J.; Knowles, M. A.

    1993-01-01

    The gene structure and expression of the related peptide regulatory factors TGF beta 1 and TGF beta 2 were studied in a panel of seven urothelial carcinoma cell lines and 40 transitional cell carcinomas. The latter comprised 15 grade 1, 18 grade 2 and 5 grade 3 tumours and two cases of carcinoma in situ. Control tissues included ten matched 'field' biopsies and 17 other biopsies including 11 biopsies of macroscopically normal urothelium, two of which were from patients with no history of bladder cancer. No amplification of rearrangements of either TGF beta 1 or TGF beta 2 were detected in any sample. A complex pattern of expression or the two genes was found in the urothelial cell lines. High, but variable levels of the 2.5 kb TGF beta 1 transcript were detected and lower and more variable levels of the three (4.1 kb, 5.1 kb and 6.5 kb) transcripts of TGF beta 2 were detected. Although those cell lines expressing most TGF beta 1 tended to express less TGF beta 2 transcript there was no clear-cut relationship. In comparison, no TGF beta 2 transcript was identified in any primary transitional cell carcinoma or control tissue. Markedly reduced or undetectable levels of TGF beta 1 transcript were detected in 4/15 (26%) grade 1, 5/18 (28%) grade 2 and 3/5 (60%) grade 3 tumours. There was no clear relationship to tumour stage, lymphocytic infiltration or stromal content of the tumours. Clinical review one year after the 2 year period of tumour collection showed that 6/9 (66%) of patients with tumours with reduced levels of transcript had died or had disease which was not controllable by local resection and 3/9 (33%) had developed tumour re-occurrences. In comparison, in the group with normal levels of expression of TGF beta 1, 3/18 (17%) had disease which was not controllable by local means, 9/18 (50%) had tumour re-occurrence and 6/18 (33%) had no evidence of disease. The association of reduced expression of TGF beta 1 and advanced disease was statistically significant

  13. Inducing a Concurrent Motor Load Reduces Categorization Precision for Facial Expressions

    PubMed Central

    2015-01-01

    Motor theories of expression perception posit that observers simulate facial expressions within their own motor system, aiding perception and interpretation. Consistent with this view, reports have suggested that blocking facial mimicry induces expression labeling errors and alters patterns of ratings. Crucially, however, it is unclear whether changes in labeling and rating behavior reflect genuine perceptual phenomena (e.g., greater internal noise associated with expression perception or interpretation) or are products of response bias. In an effort to advance this literature, the present study introduces a new psychophysical paradigm for investigating motor contributions to expression perception that overcomes some of the limitations inherent in simple labeling and rating tasks. Observers were asked to judge whether smiles drawn from a morph continuum were sincere or insincere, in the presence or absence of a motor load induced by the concurrent production of vowel sounds. Having confirmed that smile sincerity judgments depend on cues from both eye and mouth regions (Experiment 1), we demonstrated that vowel production reduces the precision with which smiles are categorized (Experiment 2). In Experiment 3, we replicated this effect when observers were required to produce vowels, but not when they passively listened to the same vowel sounds. In Experiments 4 and 5, we found that gender categorizations, equated for difficulty, were unaffected by vowel production, irrespective of the presence of a smiling expression. These findings greatly advance our understanding of motor contributions to expression perception and represent a timely contribution in light of recent high-profile challenges to the existing evidence base. PMID:26618622

  14. Inactivation of mitogen-activated protein kinase signaling pathway reduces caspase-14 expression in impaired keratinocytes

    PubMed Central

    Dang, Ningning; Pang, Shuguang; Song, Haiyan; An, Liguo; Ma, Xiaoli

    2016-01-01

    Objective(s): Several investigations have revealed that caspase-14 is responsible for the epidermal differentiation and cornification, as well as the regulation of moisturizing effect. However, the precise regulation mechanism is still not clear. This study was aimed to investigate the expression of caspase-14 in filaggrin-deficient normal human epidermal keratinocytes (NHEKs) and to explore the possible mechanism that contributes to the regulation of caspase-14. Materials and Methods: The filaggrin-deficient NHEKs were induced by transfection with lentivirus (LV) vector encoding small hairpin RNAs (shRNA). The inhibitors SB203580, PD98059 and SP600125 were used for suppressing the expression of p38 mitogen-activated protein kinase (MAPK), p44/42 MAPK and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK). The expression of filaggrin, p38 MAPK, p44/42 MAPK and SAPK/JNK, caspase-14, keratin1and keratin2 were detected by western blot. Results: In filaggrin-deficient NHEKs, the expression of p38, p44/42 MAPK and SAPK/JNK and caspase-14 were significantly decreased. The inhibition of p38 and SAPK/JNK reduced the expression of caspase-14, while the p44/42 MAPK showed no consistent effects. Moreover, the filaggrin knockdown decreased the expression of keratin2, but had no effects on the level of keratin1. Conclusion: The decreased expression of caspase-14 in filaggrin-deficient NHEKs may be induced by the inactivation of MAPK signaling pathway. These provide a novel perspective to understand the mechanism for the protective effects of filaggrin and caspase-14 on skin barrier function. PMID:27096061

  15. Acute Heat Stress and Reduced Nutrient Intake Alter Intestinal Proteomic Profile and Gene Expression in Pigs

    PubMed Central

    Pearce, Sarah C.; Lonergan, Steven M.; Huff-Lonergan, Elisabeth; Baumgard, Lance H.; Gabler, Nicholas K.

    2015-01-01

    Heat stress and reduced feed intake negatively affect intestinal integrity and barrier function. Our objective was to compare ileum protein profiles of pigs subjected to 12 hours of HS, thermal neutral ad libitum feed intake, or pair-fed to heat stress feed intake under thermal neutral conditions (pair-fed thermal neutral). 2D-Differential In Gel Electrophoresis and gene expression were performed. Relative abundance of 281 and 138 spots differed due to heat stress, compared to thermal neutral and pair-fed thermal neutral pigs, respectively. However, only 20 proteins were different due to feed intake (thermal neutral versus pair-fed thermal neutral). Heat stress increased mRNA expression of heat shock proteins and protein abundance of heat shock proteins 27, 70, 90-α and β were also increased. Heat stress reduced ileum abundance of several metabolic enzymes, many of which are involved in the glycolytic or TCA pathways, indicating a change in metabolic priorities. Stress response enzymes peroxiredoxin-1 and peptidyl-prolyl cis-trans isomerase A were decreased in pair-fed thermal neutral and thermal neutral pigs compared to heat stress. Heat stress increased mRNA abundance markers of ileum hypoxia. Altogether, these data show that heat stress directly alters intestinal protein and mRNA profiles largely independent of reduced feed intake. These changes may be related to the reduced intestinal integrity associated with heat stress. PMID:26575181

  16. IL-4 enhances expression and function of surface IgM in CLL cells.

    PubMed

    Aguilar-Hernandez, Maria M; Blunt, Matthew D; Dobson, Rachel; Yeomans, Alison; Thirdborough, Stephen; Larrayoz, Marta; Smith, Lindsay D; Linley, Adam; Strefford, Jonathan C; Davies, Andrew; Johnson, Peter M W; Savelyeva, Natalia; Cragg, Mark S; Forconi, Francesco; Packham, Graham; Stevenson, Freda K; Steele, Andrew J

    2016-06-16

    Kinase inhibitors targeting the B-cell receptor (BCR) are now prominent in the treatment of chronic lymphocytic leukemia (CLL). We have focused here on interleukin 4 (IL-4), a cytokine that protects normal and malignant B cells from apoptosis and increases surface immunoglobulin M (sIgM) expression on murine splenic B cells. First, we have demonstrated that IL-4 treatment increased sIgM expression in vitro on peripheral blood B cells obtained from healthy individuals. In CLL, IL-4 target genes are overexpressed in cells purified from the lymph nodes of patients compared with cells derived from matched blood and bone marrow samples. As for normal B cells, IL-4 increased sIgM expression on CLL cells in vitro, especially in samples expressing unmutated V-genes. IL-4-induced sIgM expression was associated with increased receptor signalling activity, measured by anti-IgM-induced calcium mobilization, and with increased expression of CD79B messenger RNA and protein, and the "mature" glycoform of sIgM. Importantly, the ability of the BCR-associated kinase inhibitors idelalisib and ibrutinib, approved for treatment of CLL and other B-cell malignancies, to inhibit anti-IgM-induced signalling was reduced following IL-4 pretreatment in samples from the majority of patients. In contrast to stimulatory effects on sIgM, IL-4 decreased CXCR4 and CXCR5 expression; therefore, CLL cells, particularly within the progressive unmutated V-gene subset, may harness the ability of IL-4 to promote BCR signalling and B-cell retention within lymph nodes. Effects of IL-4 were mediated via JAK3/STAT6 and we propose a potential role for JAK inhibitors in combination with BCR kinase inhibitors for the treatment of CLL. PMID:27002119

  17. Expression of a bacterial 3-dehydroshikimate dehydratase reduces lignin content and improves biomass saccharification efficiency.

    PubMed

    Eudes, Aymerick; Sathitsuksanoh, Noppadon; Baidoo, Edward E K; George, Anthe; Liang, Yan; Yang, Fan; Singh, Seema; Keasling, Jay D; Simmons, Blake A; Loqué, Dominique

    2015-12-01

    Lignin confers recalcitrance to plant biomass used as feedstocks in agro-processing industries or as source of renewable sugars for the production of bioproducts. The metabolic steps for the synthesis of lignin building blocks belong to the shikimate and phenylpropanoid pathways. Genetic engineering efforts to reduce lignin content typically employ gene knockout or gene silencing techniques to constitutively repress one of these metabolic pathways. Recently, new strategies have emerged offering better spatiotemporal control of lignin deposition, including the expression of enzymes that interfere with the normal process for cell wall lignification. In this study, we report that expression of a 3-dehydroshikimate dehydratase (QsuB from Corynebacterium glutamicum) reduces lignin deposition in Arabidopsis cell walls. QsuB was targeted to the plastids to convert 3-dehydroshikimate - an intermediate of the shikimate pathway - into protocatechuate. Compared to wild-type plants, lines expressing QsuB contain higher amounts of protocatechuate, p-coumarate, p-coumaraldehyde and p-coumaryl alcohol, and lower amounts of coniferaldehyde, coniferyl alcohol, sinapaldehyde and sinapyl alcohol. 2D-NMR spectroscopy and pyrolysis-gas chromatography/mass spectrometry (pyro-GC/MS) reveal an increase of p-hydroxyphenyl units and a reduction of guaiacyl units in the lignin of QsuB lines. Size-exclusion chromatography indicates a lower degree of lignin polymerization in the transgenic lines. Therefore, our data show that the expression of QsuB primarily affects the lignin biosynthetic pathway. Finally, biomass from these lines exhibits more than a twofold improvement in saccharification efficiency. We conclude that the expression of QsuB in plants, in combination with specific promoters, is a promising gain-of-function strategy for spatiotemporal reduction of lignin in plant biomass. PMID:25583257

  18. Expression of a bacterial 3-dehydroshikimate dehydratase reduces lignin content and improves biomass saccharification efficiency

    DOE PAGESBeta

    Eudes, Aymerick; Sathitsuksanoh, Noppadon; Baidoo, Edward E. K.; George, Anthe; Liang, Yan; Yang, Fan; Singh, Seema; Keasling, Jay D.; Simmons, Blake A.; Loqué, Dominique

    2015-01-13

    Lignin confers recalcitrance to plant biomass used as feedstocks in agro-processing industries or as source of renewable sugars for the production of bioproducts. The metabolic steps for the synthesis of lignin building blocks belong to the shikimate and phenylpropanoid pathways. Genetic engineering efforts to reduce lignin content typically employ gene knockout or gene silencing techniques to constitutively repress one of these metabolic pathways. Recently, new strategies have emerged offering better spatiotemporal control of lignin deposition, including the expression of enzymes that interfere with the normal process for cell wall lignification. In this study, we report that expression of a 3-dehydroshikimatemore » dehydratase (QsuB from Corynebacterium glutamicum) reduces lignin deposition in Arabidopsis cell walls. QsuB was targeted to the plastids to convert 3-dehydroshikimate – an intermediate of the shikimate pathway – into protocatechuate. Compared to wild-type plants, lines expressing QsuB contain higher amounts of protocatechuate, p-coumarate, p-coumaraldehyde and p-coumaryl alcohol, and lower amounts of coniferaldehyde, coniferyl alcohol, sinapaldehyde and sinapyl alcohol. 2D-NMR spectroscopy and pyrolysis-gas chromatography/mass spectrometry (pyro-GC/MS) reveal an increase of p-hydroxyphenyl units and a reduction of guaiacyl units in the lignin of QsuB lines. Size-exclusion chromatography indicates a lower degree of lignin polymerization in the transgenic lines. Therefore, our data show that the expression of QsuB primarily affects the lignin biosynthetic pathway. Finally, biomass from these lines exhibits more than a twofold improvement in saccharification efficiency. We conclude that the expression of QsuB in plants, in combination with specific promoters, is a promising gain-of-function strategy for spatiotemporal reduction of lignin in plant biomass.« less

  19. Reduced mRNA expression levels of MBD2 and MBD3 in gastric carcinogenesis.

    PubMed

    Pontes, Thaís Brilhante; Chen, Elizabeth Suchi; Gigek, Carolina Oliveira; Calcagno, Danielle Queiroz; Wisnieski, Fernanda; Leal, Mariana Ferreira; Demachki, Samia; Assumpção, Paulo Pimentel; Artigiani, Ricardo; Lourenço, Laércio Gomes; Burbano, Rommel Rodriguez; Arruda Cardoso Smith, Marília

    2014-04-01

    Aberrant methylation has been reported in several neoplasias, including gastric cancer. The methyl-CpG-binding domain (MBD) family proteins have been implicated in the chromatin remodeling process, leading to the modulation of gene expression. To evaluate the role of MBD2 and MBD3 in gastric carcinogenesis and the possible association with clinicopathological characteristics, we assessed the mRNA levels and promoter methylation patterns in gastric tissues. In this study, MBD2 and MBD3 mRNA levels were determined by RT-qPCR in 28 neoplastic and adjacent nonneoplastic and 27 gastritis and non-gastritis samples. The promoter methylation status was determined by bisulfite sequencing, and we found reduced MBD2 and MBD3 levels in the neoplastic samples compared with the other groups. Moreover, a strong correlation between the MBD2 and MBD3 expression levels was observed in each set of paired samples. Our data also showed that the neoplastic tissues exhibited higher MBD2 promoter methylation than the other groups. Interestingly, the non-gastritis group was the only one with positive methylation in the MBD3 promoter region. Furthermore, a weak correlation between gene expression and methylation was observed. Therefore, our data suggest that DNA methylation plays a minor role in the regulation of MBD2 and MBD3 expression, and the presence of methylation at CpGs that interact with transcription factor complexes might also be involved in the modulation of these genes. Moreover, reduced mRNA expression of MBD2 and MBD3 is implicated in gastric carcinogenesis, and thus, further investigations about these genes should be conducted for a better understanding of the role of abnormal methylation involved in this neoplasia. PMID:24338710

  20. Expression of a bacterial 3-dehydroshikimate dehydratase reduces lignin content and improves biomass saccharification efficiency

    SciTech Connect

    Eudes, Aymerick; Sathitsuksanoh, Noppadon; Baidoo, Edward E. K.; George, Anthe; Liang, Yan; Yang, Fan; Singh, Seema; Keasling, Jay D.; Simmons, Blake A.; Loqué, Dominique

    2015-01-13

    Lignin confers recalcitrance to plant biomass used as feedstocks in agro-processing industries or as source of renewable sugars for the production of bioproducts. The metabolic steps for the synthesis of lignin building blocks belong to the shikimate and phenylpropanoid pathways. Genetic engineering efforts to reduce lignin content typically employ gene knockout or gene silencing techniques to constitutively repress one of these metabolic pathways. Recently, new strategies have emerged offering better spatiotemporal control of lignin deposition, including the expression of enzymes that interfere with the normal process for cell wall lignification. In this study, we report that expression of a 3-dehydroshikimate dehydratase (QsuB from Corynebacterium glutamicum) reduces lignin deposition in Arabidopsis cell walls. QsuB was targeted to the plastids to convert 3-dehydroshikimate – an intermediate of the shikimate pathway – into protocatechuate. Compared to wild-type plants, lines expressing QsuB contain higher amounts of protocatechuate, p-coumarate, p-coumaraldehyde and p-coumaryl alcohol, and lower amounts of coniferaldehyde, coniferyl alcohol, sinapaldehyde and sinapyl alcohol. 2D-NMR spectroscopy and pyrolysis-gas chromatography/mass spectrometry (pyro-GC/MS) reveal an increase of p-hydroxyphenyl units and a reduction of guaiacyl units in the lignin of QsuB lines. Size-exclusion chromatography indicates a lower degree of lignin polymerization in the transgenic lines. Therefore, our data show that the expression of QsuB primarily affects the lignin biosynthetic pathway. Finally, biomass from these lines exhibits more than a twofold improvement in saccharification efficiency. We conclude that the expression of QsuB in plants, in combination with specific promoters, is a promising gain-of-function strategy for spatiotemporal reduction of lignin in plant biomass.

  1. Nanorough titanium surfaces reduce adhesion of Escherichia coli and Staphylococcus aureus via nano adhesion points.

    PubMed

    Lüdecke, Claudia; Roth, Martin; Yu, Wenqi; Horn, Uwe; Bossert, Jörg; Jandt, Klaus D

    2016-09-01

    Microbial adhesion to natural and synthetic materials surfaces is a key issue e.g. in food industry, sewage treatment and most importantly in the biomedical field. The current development and progress in nanoscale structuring of materials surfaces to control microbial adhesion requires an advanced understanding of the microbe-material-interaction. This study aimed to investigate the nanostructure of the microbe-material-interface and link it to microbial adhesion kinetics as function of titanium surface nanoroughness to gain new insight into controlling microbial adhesion via materials' surface nanoroughness. Adhesion of Escherichia coli and Staphylococcus aureus was statistically significantly reduced (p≤0.05) by 55.6 % and 40.5 %, respectively, on physical vapor deposited titanium thin films with a nanoroughness of 6nm and the lowest surface peak density compared to 2nm with the highest surface peak density. Cross-sectioning of the microbial cells with a focused ion beam (FIB) and SEM imaging provided for the first time direct insight into the titanium-microbe-interface. High resolution SEM micrographs gave evidence that the surface peaks are the loci of initial contact between the microbial cells and the material's surface. In a qualitative model we propose that the initial microbial adhesion on nanorough surfaces is controlled by the titanium surface peak density via nano adhesion points. This new understanding will help towards the design of materials surfaces for controlling microbial adhesion. PMID:27288816

  2. Sub-micrometer scale surface roughness of titanium reduces fibroblasts function.

    PubMed

    Migita, Satoshi; Okuyama, So; Araki, Kunitaka

    2016-01-01

    Titanium and its alloys are conventionally used to produce medical devices, but their biocompatibility has not yet been optimized. Surface modification, especially control of the surface roughness of titanium, is one strategy for improving biocompatibility and providing effective binding to hard tissue. However, the soft tissue compatibility of metallic materials is currently poorly understood, and effective techniques for tight binding between metal surfaces and soft tissue are still under development. Therefore, we here investigated whether the surface roughness of titanium affects fibroblast adhesion and proliferation. Our results showed that a surface roughness of ~100 nm reduces fibroblast function. On such surfaces, distinct focal adhesion was not observed. These findings improve the general understanding of the binding compatibility between soft tissues and metallic materials. PMID:26689819

  3. Short-chain ceramides depress integrin cell surface expression and function in colorectal cancer cells.

    PubMed

    Morad, Samy A F; Bridges, Lance C; Almeida Larrea, Alex D; Mayen, Anthony L; MacDougall, Matthew R; Davis, Traci S; Kester, Mark; Cabot, Myles C

    2016-07-01

    Colorectal cancer (CRC) is highly metastatic, significantly so to liver, a characteristic that embodies one of the most challenging aspects of treatment. The integrin family of cell-cell and cell-matrix adhesion receptors plays a central role in migration and invasion, functions that underlie metastatic potential. In the present work we sought to determine the impact of ceramide, which plays a key modulatory role in cancer suppression, on integrin cell surface expression and function in CRC cells in order to reveal possible ceramide-centric effects on tumor cell motility. Human CRC cells LoVo, HT-29, and HCT-116 were employed, which represent lines established from primary and metastatic sites. A cell-permeable, short-chain analog, C6-ceramide, was used as ceramide mimic. Exposure of cells to C6-ceramide (24 h) promoted a dose-dependent (2.5-10 µM) decrease in the expression of cell surface β1 and β4 integrin subunits in all cell lines; at 10 µM C6-ceramide, the decreases ranged from 30 to 50% of the control. Expression of cell surface αVβ6 integrin, which is associated with advanced invasion in CRC, was also suppressed by C6-ceramide. Decreases in integrin expression translated to diminished cellular adhesion, 50% of the control at 5 µM C6-ceramide, and markedly reduced cellular migration, approximately 30-40% of the control in all cell lines. Physicochemical examination revealed potent efficacy of nano-formulated C6-ceramide, but inferior activity of dihydro-C6-ceramide and L-C6-ceramide, compared to the unsaturated counterpart and the natural d-enantiomer, respectively. These studies demonstrate novel actions of ceramides that may have application in suppression of tumor metastasis, in addition to their known tumor suppressor effects. PMID:27045476

  4. The MS Risk Allele of CD40 Is Associated with Reduced Cell-Membrane Bound Expression in Antigen Presenting Cells: Implications for Gene Function

    PubMed Central

    Field, Judith; Shahijanian, Fernando; Schibeci, Stephen; Johnson, Laura; Gresle, Melissa; Laverick, Louise; Parnell, Grant; Stewart, Graeme; McKay, Fiona; Kilpatrick, Trevor; Butzkueven, Helmut; Booth, David

    2015-01-01

    Human genetic and animal studies have implicated the costimulatory molecule CD40 in the development of multiple sclerosis (MS). We investigated the cell specific gene and protein expression variation controlled by the CD40 genetic variant(s) associated with MS, i.e. the T-allele at rs1883832. Previously we had shown that the risk allele is expressed at a lower level in whole blood, especially in people with MS. Here, we have defined the immune cell subsets responsible for genotype and disease effects on CD40 expression at the mRNA and protein level. In cell subsets in which CD40 is most highly expressed, B lymphocytes and dendritic cells, the MS-associated risk variant is associated with reduced CD40 cell-surface protein expression. In monocytes and dendritic cells, the risk allele additionally reduces the ratio of expression of full-length versus truncated CD40 mRNA, the latter encoding secreted CD40. We additionally show that MS patients, regardless of genotype, express significantly lower levels of CD40 cell-surface protein compared to unaffected controls in B lymphocytes. Thus, both genotype-dependent and independent down-regulation of cell-surface CD40 is a feature of MS. Lower expression of a co-stimulator of T cell activation, CD40, is therefore associated with increased MS risk despite the same CD40 variant being associated with reduced risk of other inflammatory autoimmune diseases. Our results highlight the complexity and likely individuality of autoimmune pathogenesis, and could be consistent with antiviral and/or immunoregulatory functions of CD40 playing an important role in protection from MS. PMID:26068105

  5. Reduced expression of PNUTS leads to activation of Rb-phosphatase and caspase-mediated apoptosis.

    PubMed

    De Leon, Gabriel; Sherry, Tara C; Krucher, Nancy A

    2008-06-01

    There is abundant evidence that Retinoblastoma (Rb) activity is important in the control of cell proliferation and apoptosis. Reversible phosphorylation of the Rb protein that is carried out by cyclin dependent kinases and Protein phosphatase 1 (PP1) regulates its functions. A PP1 interacting protein, PNUTS (Phosphatase Nuclear Targeting Subunit) is proposed to be a regulator of Rb phosphorylation. In this study, PNUTS knockdown in MCF7, SKA and HCT116 cancer cells causes a reduction in viability due to increased apoptosis. However, normal cells (MCF10A breast and CCD-18Co colon) do not exhibit reduced viability when PNUTS expression is diminished. PNUTS knockdown has no effect in Rb-null Saos-2 cells. However, when Rb is stably expressed in Saos-2 cells, PNUTS knockdown reduces cell number. Knockdown of PNUTS in p53-/- HCT116 cells indicates that p53 is dispensable for the induction of apoptosis. Loss of PNUTS expression results in increased Rb-phosphatase activity and Rb dephosphorylation. E2F1 dissociates from Rb in cells depleted of PNUTS and the resulting apoptosis is dependent on caspase-8. These results indicate that Rb phosphorylation state can be manipulated by targeting Rb phosphatase activity and suggest that PNUTS may be a potential target for therapeutic pro-apoptotic strategies. PMID:18360108

  6. Reduced expression of the WW domain-containing oxidoreductase in human hematopoietic malignancies

    PubMed Central

    LUO, LINGQING; CHEN, YAN; CHENG, XIAO; LIN, YAZHEN; FU, XIAODAN; LI, DAN; CUI, ZHAOLEI; LIN, DONGHONG

    2016-01-01

    The role of the WW domain-containing oxidoreductase (WWOX) gene in multiple types of solid human cancers has been documented extensively thus far. Recently, we investigated the in vitro effects of WWOX overexpression and observed marked growth arrest in human leukemia cells; however, the clinical characterization of WWOX in leukemia remains poorly investigated. The present study evaluated the WWOX expression profiles of 182 patients with leukemia of different types and 5 leukemic cell lines, using reverse transcription-polymerase chain reaction and immunofluorescence analysis. The results found that WWOX mRNA and WWOX protein expression was significantly reduced or absent in the leukemia cases and cell lines compared with paired controls. The WWOX-positive rate was also lower in the leukemia cases compared with the rate of the normal controls. Notably, the WWOX level was reduced in newly diagnosed and relapsed cases, or in chronic myelogenous leukemia in the blastic phase, yet elevated in remission samples. Moreover, WWOX-negative cases exhibited WWOX expression restoration following induced remission. These findings suggest that WWOX may contribute to the occurrence and development of leukemia, and that it has potential to be a good biomarker or predictor for leukemia therapy. PMID:27313745

  7. Lower expression of Nrdp1 in human glioma contributes tumor progression by reducing apoptosis.

    PubMed

    Shi, Hengliang; Du, Jin; Wang, Lei; Zheng, Bao; Gong, Hui; Wu, Yuxuan; Tang, Yuan; Gao, Yong; Yu, Rutong

    2014-10-01

    Ubiquitin ligase Nrdp1 (neuregulin receptor degradation protein 1) plays important roles in multiple physiological process because it can ubiquitinate various substrates such as ErbB3, BRUCE, MyD88, C/EBPβ, and Parkin, and so forth. In addition to the physiological function, it was also found to be involved in tumor progression. It has been shown that loss of Nrdp1 enhances breast cancer cell growth. Up to now, the role of Nrdp1 in glioma has not been elucidated. Here, we reported that Nrdp1 as well as cleaved caspase 3 was lower expressed in human glioma tissues comparing with the nontumorous. And then we found that the expression of Nrdp1 and cleaved caspase 3 was increased in the treatment of Temozolomide (TMZ), a drug for glioma chemotherapy. Further investigation indicated that transient transfection of Nrdp1 significantly promoted cell apoptosis by aggravating the degradation of BRUCE and activation of caspase 3. In addition, overexpression of Nrdp1 augmented TMZ induced apoptosis by evaluating the degradation of BRUCE and the activation of caspase 3, while silencing of Nrdp1 reduced the sensitivity to the TMZ by inhibiting the degradation of BRUCE and the activation of caspase 3 in human glioma cells. These observations show that Nrdp1 is a pro-apoptotic protein in human glioma and lower expression of Nrdp1 in human glioma may promote tumor progression by reducing apoptosis, suggesting that Nrdp1 may be an important regulator in the development of human glioma. PMID:25355637

  8. Brain-derived neurotrophic factor reduces amyloidogenic processing through control of SORLA gene expression.

    PubMed

    Rohe, Michael; Synowitz, Michael; Glass, Rainer; Paul, Steven M; Nykjaer, Anders; Willnow, Thomas E

    2009-12-01

    Sorting protein-related receptor with A-type repeats (SORLA) is a major risk factor in cellular processes leading to Alzheimer's disease (AD). It acts as sorting receptor for the amyloid precursor protein (APP) that regulates intracellular trafficking and processing into amyloidogenic-beta peptides (A beta). Overexpression of SORLA in neurons reduces while inactivation of gene expression (as in knock-out mouse models) accelerates amyloidogenic processing and senile plaque formation. The current study aimed at identifying molecular pathways that control SORLA gene transcription in vivo and that may contribute to low levels of receptor expression in the brain of patients with AD. Using screening approaches in primary neurons, we identified brain-derived neurotrophic factor (BDNF) as a major inducer of Sorla that activates receptor gene transcription through the ERK (extracellular regulated kinase) pathway. In line with a physiological role as regulator of Sorla, expression of the receptor is significantly impaired in mouse models with genetic (Bdnf(-/-)) or disease-related loss of BDNF activity in the brain (Huntington's disease). Intriguingly, exogenous application of BDNF reduced A beta production in primary neurons and in the brain of wild-type mice in vivo, but not in animals genetically deficient for Sorla. These findings demonstrate that the beneficial effects ascribed to BDNF in APP metabolism act through induction of Sorla that encodes a negative regulator of neuronal APP processing. PMID:20007471

  9. Reduced Myelin Basic Protein and Actin-Related Gene Expression in Visual Cortex in Schizophrenia

    PubMed Central

    Matthews, Paul R.; Eastwood, Sharon L.; Harrison, Paul J.

    2012-01-01

    Most brain gene expression studies of schizophrenia have been conducted in the frontal cortex or hippocampus. The extent to which alterations occur in other cortical regions is not well established. We investigated primary visual cortex (Brodmann area 17) from the Stanley Neuropathology Consortium collection of tissue from 60 subjects with schizophrenia, bipolar disorder, major depression, or controls. We first carried out a preliminary array screen of pooled RNA, and then used RT-PCR to quantify five mRNAs which the array identified as differentially expressed in schizophrenia (myelin basic protein [MBP], myelin-oligodendrocyte glycoprotein [MOG], β-actin [ACTB], thymosin β-10 [TB10], and superior cervical ganglion-10 [SCG10]). Reduced mRNA levels were confirmed by RT-PCR for MBP, ACTB and TB10. The MBP reduction was limited to transcripts containing exon 2. ACTB and TB10 mRNAs were also decreased in bipolar disorder. None of the transcripts were altered in subjects with major depression. Reduced MBP mRNA in schizophrenia replicates findings in other brain regions and is consistent with oligodendrocyte involvement in the disorder. The decreases in expression of ACTB, and the actin-binding protein gene TB10, suggest changes in cytoskeletal organisation. The findings confirm that the primary visual cortex shows molecular alterations in schizophrenia and extend the evidence for a widespread, rather than focal, cortical pathophysiology. PMID:22675524

  10. Blood-Gene Expression Reveals Reduced Circadian Rhythmicity in Individuals Resistant to Sleep Deprivation

    PubMed Central

    Arnardottir, Erna S.; Nikonova, Elena V.; Shockley, Keith R.; Podtelezhnikov, Alexei A.; Anafi, Ron C.; Tanis, Keith Q.; Maislin, Greg; Stone, David J.; Renger, John J.; Winrow, Christopher J.; Pack, Allan I.

    2014-01-01

    Study Objectives: To address whether changes in gene expression in blood cells with sleep loss are different in individuals resistant and sensitive to sleep deprivation. Design: Blood draws every 4 h during a 3-day study: 24-h normal baseline, 38 h of continuous wakefulness and subsequent recovery sleep, for a total of 19 time-points per subject, with every 2-h psychomotor vigilance task (PVT) assessment when awake. Setting: Sleep laboratory. Participants: Fourteen subjects who were previously identified as behaviorally resistant (n = 7) or sensitive (n = 7) to sleep deprivation by PVT. Intervention: Thirty-eight hours of continuous wakefulness. Measurements and Results: We found 4,481 unique genes with a significant 24-h diurnal rhythm during a normal sleep-wake cycle in blood (false discovery rate [FDR] < 5%). Biological pathways were enriched for biosynthetic processes during sleep. After accounting for circadian effects, two genes (SREBF1 and CPT1A, both involved in lipid metabolism) exhibited small, but significant, linear changes in expression with the duration of sleep deprivation (FDR < 5%). The main change with sleep deprivation was a reduction in the amplitude of the diurnal rhythm of expression of normally cycling probe sets. This reduction was noticeably higher in behaviorally resistant subjects than sensitive subjects, at any given P value. Furthermore, blood cell type enrichment analysis showed that the expression pattern difference between sensitive and resistant subjects is mainly found in cells of myeloid origin, such as monocytes. Conclusion: Individual differences in behavioral effects of sleep deprivation are associated with differences in diurnal amplitude of gene expression for genes that show circadian rhythmicity. Citation: Arnardottir ES, Nikonova EV, Shockley KR, Podtelezhnikov AA, Anafi RC, Tanis KQ, Maislin G, Stone DJ, Renger JJ, Winrow CJ, Pack AI. Blood-gene expression reveals reduced circadian rhythmicity in individuals resistant to

  11. Reduced Tau protein expression is associated with frontotemporal degeneration with progranulin mutation.

    PubMed

    Papegaey, Anthony; Eddarkaoui, Sabiha; Deramecourt, Vincent; Fernandez-Gomez, Francisco-Jose; Pantano, Pierre; Obriot, Hélène; Machala, Camille; Anquetil, Vincent; Camuzat, Agnès; Brice, Alexis; Maurage, Claude-Alain; Le Ber, Isabelle; Duyckaerts, Charles; Buée, Luc; Sergeant, Nicolas; Buée-Scherrer, Valérie

    2016-01-01

    Reduction of Tau protein expression was described in 2003 by Zhukareva et al. in a variant of frontotemporal lobar degeneration (FTLD) referred to as diagnosis of dementia lacking distinctive histopathology, then re-classified as FTLD with ubiquitin inclusions. However, the analysis of Tau expression in FTLD has not been reconsidered since then. Knowledge of the molecular basis of protein aggregates and genes that are mutated in the FTLD spectrum would enable to determine whether the "Tau-less" is a separate pathological entity or if it belongs to an existing subclass of FTLD. To address this question, we have analyzed Tau expression in the frontal brain areas from control, Alzheimer's disease and FTLD cases, including FTLD- Tau (MAPT), FTLD-TDP (sporadic, FTLD-TDP-GRN, FTLD-TDP-C9ORF72) and sporadic FTLD-FUS, using western blot and 2D-DIGE (Two-Dimensional fluorescence Difference Gel Electrophoresis) approaches. Surprisingly, we found that most of the FTLD-TDP-GRN brains are characterized by a huge reduction of Tau protein expression without any decrease in Tau mRNA levels. Interestingly, only cases affected by point mutations, rather than cases with total deletion of one GRN allele, seem to be affected by this reduction of Tau protein expression. Moreover, proteomic analysis highlighted correlations between reduced Tau protein level, synaptic impairment and massive reactive astrogliosis in these FTLD-GRN cases. Consistent with a recent study, our data also bring new insights regarding the role of progranulin in neurodegeneration by suggesting its involvement in lysosome and synaptic regulation. Together, our results demonstrate a strong association between progranulin deficiency and reduction of Tau protein expression that could lead to severe neuronal and glial dysfunctions. Our study also indicates that this FTLD-TDP-GRN subgroup could be part as a distinct entity of FTLD classification. PMID:27435172

  12. New Variance-Reducing Methods for the PSD Analysis of Large Optical Surfaces

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin

    2010-01-01

    Edge data of a measured surface map of a circular optic result in large variance or "spectral leakage" behavior in the corresponding Power Spectral Density (PSD) data. In this paper we present two new, alternative methods for reducing such variance in the PSD data by replacing the zeros outside the circular area of a surface map by non-zero values either obtained from a PSD fit (method 1) or taken from the inside of the circular area (method 2).

  13. Self-aligned polysilicon MEMS-reduced mask count surface micromachining

    NASA Astrophysics Data System (ADS)

    Noworolski, J. Mark; Sanders, Seth R.

    1998-09-01

    A self-aligned reduced mask count micromachined polysilicon on nitride (SAMPSON) surface micromachining process is introduced. The self-alignment fabrication concept enables rapid fabrication, improves yields, and reduces parasitic capacitance of MEM devices. For many MEM devices the SAMPSON process results in a one mask savings over more conventional approaches. As a demonstration of the fabrication technique a burst-proof surface micromachined polysilicon resonant pressure sensor is fabricated using the SAMPSON process. This pressure sensor does not require a sealed cavity. It is also insensitive to mechanical property variations of the structural material, rendering its response essentially temperature independent.

  14. Reduced-Enrichment, Fast-Spectrum Lunar/Mars Surface Reactors

    SciTech Connect

    Poston, David I.; Marcille, Thomas F.; Kapernick, Richard J.; Sadasivan, Pratap; Amiri, Benjamin W.

    2006-07-01

    This report investigates the potential for reduced-enrichment, un-moderated surface reactors. The potential programmatic advantages of a reduced safeguards classification are discussed, along with design options that could allow a Cat III inventory surface reactor. Two potential reactor Cat III designs are presented, each with a thermal power of 100 kWt and a 5 year life: one is fueled with SS/UO{sub 2} fuel pins and the other with SS/UN fuel pins. The mass and performance parameters of these designs are compared to each other, and to a Cat III UZrH-fueled, moderated-spectrum design. (authors)

  15. Expression of Arabidopsis Hexokinase in Citrus Guard Cells Controls Stomatal Aperture and Reduces Transpiration.

    PubMed

    Lugassi, Nitsan; Kelly, Gilor; Fidel, Lena; Yaniv, Yossi; Attia, Ziv; Levi, Asher; Alchanatis, Victor; Moshelion, Menachem; Raveh, Eran; Carmi, Nir; Granot, David

    2015-01-01

    Hexokinase (HXK) is a sugar-phosphorylating enzyme involved in sugar-sensing. It has recently been shown that HXK in guard cells mediates stomatal closure and coordinates photosynthesis with transpiration in the annual species tomato and Arabidopsis. To examine the role of HXK in the control of the stomatal movement of perennial plants, we generated citrus plants that express Arabidopsis HXK1 (AtHXK1) under KST1, a guard cell-specific promoter. The expression of KST1 in the guard cells of citrus plants has been verified using GFP as a reporter gene. The expression of AtHXK1 in the guard cells of citrus reduced stomatal conductance and transpiration with no negative effect on the rate of photosynthesis, leading to increased water-use efficiency. The effects of light intensity and humidity on stomatal behavior were examined in rooted leaves of the citrus plants. The optimal intensity of photosynthetically active radiation and lower humidity enhanced stomatal closure of AtHXK1-expressing leaves, supporting the role of sugar in the regulation of citrus stomata. These results suggest that HXK coordinates photosynthesis and transpiration and stimulates stomatal closure not only in annual species, but also in perennial species. PMID:26734024

  16. The Inflammatory Cytokines TWEAK and TNFα Reduce Renal Klotho Expression through NFκB

    PubMed Central

    Moreno, Juan A.; Izquierdo, Maria C.; Sanchez-Niño, Maria D.; Suárez-Alvarez, Beatriz; Lopez-Larrea, Carlos; Jakubowski, Aniela; Blanco, Julia; Ramirez, Rafael; Selgas, Rafael; Ruiz-Ortega, Marta; Egido, Jesus; Sanz, Ana B.

    2011-01-01

    Proinflammatory cytokines contribute to renal injury, but the downstream effectors within kidney cells are not well understood. One candidate effector is Klotho, a protein expressed by renal cells that has antiaging properties; Klotho-deficient mice have an accelerated aging-like phenotype, including vascular injury and renal injury. Whether proinflammatory cytokines, such as TNF and TNF-like weak inducer of apoptosis (TWEAK), modulate Klotho is unknown. In mice, exogenous administration of TWEAK decreased expression of Klotho in the kidney. In the setting of acute kidney injury induced by folic acid, the blockade or absence of TWEAK abrogated the injury-related decrease in renal and plasma Klotho levels. TWEAK, TNFα, and siRNA-mediated knockdown of IκBα all activated NFκB and reduced Klotho expression in the MCT tubular cell line. Furthermore, inhibition of NFκB with parthenolide prevented TWEAK- or TNFα-induced downregulation of Klotho. Inhibition of histone deacetylase reversed TWEAK-induced downregulation of Klotho, and chromatin immunoprecipitation showed that TWEAK promotes RelA binding to the Klotho promoter, inducing its deacetylation. In conclusion, inflammatory cytokines, such as TWEAK and TNFα, downregulate Klotho expression through an NFκB-dependent mechanism. These results may partially explain the relationship between inflammation and diseases characterized by accelerated aging of organs, including CKD. PMID:21719790

  17. relA over-expression reduces tumorigenicity and activates apoptosis in human cancer cells

    PubMed Central

    Ricca, A; Biroccio, A; Trisciuoglio, D; Cippitelli, M; Zupi, G; Bufalo, D Del

    2001-01-01

    We previously demonstrated that bcl-2 over-expression increases the malignant behaviour of the MCF7 ADR human breast cancer cell line and enhances nuclear factor-kappa B (NF-k B) transcriptional activity. Here, we investigated the direct effect of increased NF-k B activity on the tumorigenicity of MCF7 ADR cells by over-expressing the NF-k B subunit relA/p65. Surprisingly, our results demonstrated that over-expression of relA determines a considerable reduction of the tumorigenic ability in nude mice as indicated by the tumour take and the median time of tumour appearance. In vitro studies also evidenced a reduced cell proliferation and the activation of the apoptotic programme after relA over-expression. Apoptosis was associated with the production of reactive oxygen species, and the cleavage of the specific substrate Poly-ADP-ribose-polymerrase. Our data indicate that there is no general role for NF-k B in the regulation of apoptosis and tumorigenicity. In fact, even though inhibiting NF-k B activity has been reported to be lethal to tumour cells, our findings clearly suggest that an over-induction of nuclear NF-k B activity may produce the same effect. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11747334

  18. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression

    SciTech Connect

    Liu, Xin-Hua; Yao, Shen; Qiao, Rui-Fang; Levine, Alice C.; Kirschenbaum, Alexander; Pan, Jiangping; Wu, Yong; Qin, Weiping; Bauman, William A.; Cardozo, Christopher P.

    2011-10-14

    Highlights: {yields} Nerve transection increased Notch signaling in paralyzed muscle. {yields} Nandrolone prevented denervation-induced Notch signaling. {yields} Nandrolone induced the expression of an inhibitor of the Notch signaling, Numb. {yields} Reduction of denervation-induced Notch signaling by nandrolone is likely through upregulation of Numb. -- Abstract: Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy.

  19. Expression of Arabidopsis Hexokinase in Citrus Guard Cells Controls Stomatal Aperture and Reduces Transpiration

    PubMed Central

    Lugassi, Nitsan; Kelly, Gilor; Fidel, Lena; Yaniv, Yossi; Attia, Ziv; Levi, Asher; Alchanatis, Victor; Moshelion, Menachem; Raveh, Eran; Carmi, Nir; Granot, David

    2015-01-01

    Hexokinase (HXK) is a sugar-phosphorylating enzyme involved in sugar-sensing. It has recently been shown that HXK in guard cells mediates stomatal closure and coordinates photosynthesis with transpiration in the annual species tomato and Arabidopsis. To examine the role of HXK in the control of the stomatal movement of perennial plants, we generated citrus plants that express Arabidopsis HXK1 (AtHXK1) under KST1, a guard cell-specific promoter. The expression of KST1 in the guard cells of citrus plants has been verified using GFP as a reporter gene. The expression of AtHXK1 in the guard cells of citrus reduced stomatal conductance and transpiration with no negative effect on the rate of photosynthesis, leading to increased water-use efficiency. The effects of light intensity and humidity on stomatal behavior were examined in rooted leaves of the citrus plants. The optimal intensity of photosynthetically active radiation and lower humidity enhanced stomatal closure of AtHXK1-expressing leaves, supporting the role of sugar in the regulation of citrus stomata. These results suggest that HXK coordinates photosynthesis and transpiration and stimulates stomatal closure not only in annual species, but also in perennial species. PMID:26734024

  20. Lactobacilli Reduce Helicobacter pylori Attachment to Host Gastric Epithelial Cells by Inhibiting Adhesion Gene Expression.

    PubMed

    de Klerk, Nele; Maudsdotter, Lisa; Gebreegziabher, Hanna; Saroj, Sunil D; Eriksson, Beatrice; Eriksson, Olaspers Sara; Roos, Stefan; Lindén, Sara; Sjölinder, Hong; Jonsson, Ann-Beth

    2016-05-01

    The human gastrointestinal tract, including the harsh environment of the stomach, harbors a large variety of bacteria, of which Lactobacillus species are prominent members. The molecular mechanisms by which species of lactobacilli interfere with pathogen colonization are not fully characterized. In this study, we aimed to study the effect of lactobacillus strains upon the initial attachment of Helicobacter pylori to host cells. Here we report a novel mechanism by which lactobacilli inhibit adherence of the gastric pathogen H. pylori In a screen with Lactobacillus isolates, we found that only a few could reduce adherence of H. pylori to gastric epithelial cells. Decreased attachment was not due to competition for space or to lactobacillus-mediated killing of the pathogen. Instead, we show that lactobacilli act on H. pylori directly by an effector molecule that is released into the medium. This effector molecule acts on H. pylori by inhibiting expression of the adhesin-encoding gene sabA Finally, we verified that inhibitory lactobacilli reduced H. pylori colonization in an in vivo model. In conclusion, certain Lactobacillus strains affect pathogen adherence by inhibiting sabA expression and thereby reducing H. pylori binding capacity. PMID:26930708

  1. Nuclear protein import is reduced in cells expressing nuclear envelopathy-causing lamin A mutants

    SciTech Connect

    Busch, Albert; Kiel, Tilman; Heupel, Wolfgang-M.; Wehnert, Manfred; Huebner, Stefan

    2009-08-15

    Lamins, which form the nuclear lamina, not only constitute an important determinant of nuclear architecture, but additionally play essential roles in many nuclear functions. Mutations in A-type lamins cause a wide range of human genetic disorders (laminopathies). The importance of lamin A (LaA) in the spatial arrangement of nuclear pore complexes (NPCs) prompted us to study the role of LaA mutants in nuclear protein transport. Two mutants, causing prenatal skin disease restrictive dermopathy (RD) and the premature aging disease Hutchinson Gilford progeria syndrome, were used for expression in HeLa cells to investigate their impact on the subcellular localization of NPC-associated proteins and nuclear protein import. Furthermore, dynamics of the LaA mutants within the nuclear lamina were studied. We observed affected localization of NPC-associated proteins, diminished lamina dynamics for both LaA mutants and reduced nuclear import of representative cargo molecules. Intriguingly, both LaA mutants displayed similar effects on nuclear morphology and functions, despite their differences in disease severity. Reduced nuclear protein import was also seen in RD fibroblasts and impaired lamina dynamics for the nucleoporin Nup153. Our data thus represent the first study of a direct link between LaA mutant expression and reduced nuclear protein import.

  2. Reduced iNOS expression in adenoids from children with otitis media with effusion.

    PubMed

    Granath, Anna; Norrby-Teglund, Anna; Uddman, Rolf; Cardell, Lars-Olaf

    2010-12-01

    Nitric oxide (NO) is a key mediator in the local immune response of human airways. Inducible NO-synthases (iNOS), and endothelial NO-synthases (eNOS) are two enzymes known to regulate its production. The role of NO in middle ear disease is not fully known. Previous studies suggest that NO might have a dual role, both promoting and suppressing middle ear inflammation. The aim of the present study was to compare the eNOS and iNOS expression in adenoids obtained from children with otitis media with effusion (OME) with the expression seen in adenoids derived from children without middle ear disease. In addition, the expression of IL-1β and TNF-α were analyzed, because of their role in the iNOS-induction pathway. The iNOS and eNOS expression were analyzed with real-time PCR in 8 OME and 11 control adenoids. The corresponding proteins were demonstrated by immunohistochemical staining of adenoid tissue. A Luminex(®) assay was performed to analyze IL-1β and TNF-α in nasopharyngeal secretion in 10 OME and 8 controls, and immunohistochemistry was performed on adenoid tissue and imprints from the adenoid surface. Children with OME exhibited lower levels of iNOS than controls without middle ear disease. No such difference was seen for eNOS. The corresponding proteins were found mainly in conjunction with surface epithelium. No significant changes were seen among the cytokines tested. The present results indicate that local induction of iNOS in adenoids might be of importance for preventing development of OME. PMID:21073541

  3. Vitamin D improves endothelial dysfunction and restores myeloid angiogenic cell function via reduced CXCL-10 expression in systemic lupus erythematosus.

    PubMed

    Reynolds, John A; Haque, Sahena; Williamson, Kate; Ray, David W; Alexander, M Yvonne; Bruce, Ian N

    2016-01-01

    Patients with systemic lupus erythematosus (SLE) have accelerated cardiovascular disease and dysfunctional endothelial repair mechanisms. Myeloid angiogenic cells (MACs), derived from circulating monocytes, augment vascular repair by paracrine secretion of pro-angiogenic factors. We observed that SLE MACs are dysfunctional and secrete pro-inflammatory cytokines. We also found that the vitamin D receptor was transiently expressed during MAC differentiation and that in vitro, calcitriol increased differentiation of monocytes into MACs in both SLE and in a model using the prototypic SLE cytokine, interferon-alpha. The active form of vitamin D (calcitriol) restored the SLE MAC phenotype towards that of healthy subjects with reduced IL-6 secretion, and normalised surface marker expression. Calcitriol also augmented the angiogenic capacity of MACs via the down-regulation of CXCL-10. In SLE patients treated with cholecalciferol for 12 weeks, the improvement in endothelial function correlated with increase in serum 25(OH)D concentrations independently of disease activity. We also show that MACs were able to positively modulate eNOS expression in human endothelial cells in vitro, an effect further enhanced by calcitriol treatment of SLE MACs. The results demonstrate that vitamin D can positively modify endothelial repair mechanisms and thus endothelial function in a population with significant cardiovascular risk. PMID:26930567

  4. Vitamin D improves endothelial dysfunction and restores myeloid angiogenic cell function via reduced CXCL-10 expression in systemic lupus erythematosus

    PubMed Central

    Reynolds, John A.; Haque, Sahena; Williamson, Kate; Ray, David W.; Alexander, M. Yvonne; Bruce, Ian N.

    2016-01-01

    Patients with systemic lupus erythematosus (SLE) have accelerated cardiovascular disease and dysfunctional endothelial repair mechanisms. Myeloid angiogenic cells (MACs), derived from circulating monocytes, augment vascular repair by paracrine secretion of pro-angiogenic factors. We observed that SLE MACs are dysfunctional and secrete pro-inflammatory cytokines. We also found that the vitamin D receptor was transiently expressed during MAC differentiation and that in vitro, calcitriol increased differentiation of monocytes into MACs in both SLE and in a model using the prototypic SLE cytokine, interferon-alpha. The active form of vitamin D (calcitriol) restored the SLE MAC phenotype towards that of healthy subjects with reduced IL-6 secretion, and normalised surface marker expression. Calcitriol also augmented the angiogenic capacity of MACs via the down-regulation of CXCL-10. In SLE patients treated with cholecalciferol for 12 weeks, the improvement in endothelial function correlated with increase in serum 25(OH)D concentrations independently of disease activity. We also show that MACs were able to positively modulate eNOS expression in human endothelial cells in vitro, an effect further enhanced by calcitriol treatment of SLE MACs. The results demonstrate that vitamin D can positively modify endothelial repair mechanisms and thus endothelial function in a population with significant cardiovascular risk. PMID:26930567

  5. Huoxue Rongluo Tablet reduces matrix metalloproteinase-9 expression in infarcted brain tissue

    PubMed Central

    Zhou, Desheng; Li, Mei; Hu, Hua; Chen, Yao; Yang, Yang; Zhong, Jie; Liu, Lijuan

    2013-01-01

    Huoxue Rongluo Tablet was made of tall gastrodis tuber, dahurian angelica root, honeysuckle stem, grassleaf sweetflag rhizome, common flowering quince fruit, figwort root, red peony root and peach seed at a ratio of 3:2:6:2:3:3:3:3. Huoxue Rongluo Tablet is a well-established and common pre-scription for the treatment of cerebral infarction. In this study, a rat model of cerebral ischemia was established and the animals were intragastrically administered Huoxue Rongluo Tablet. This treat-ment reduced infarct volume, decreased matrix metalloproteinase-9 expression, and improved neurological function. Moreover, the effects of Huoxue Rongluo Tablet were better than those of buflomedil pyridoxal phosphate. These results indicate that Huoxue Rongluo Tablet is effective in treating cerebral infarction by regulating matrix metalloproteinase-9 protein expression. PMID:25206642

  6. Huoxue Rongluo Tablet reduces matrix metalloproteinase-9 expression in infarcted brain tissue.

    PubMed

    Zhou, Desheng; Li, Mei; Hu, Hua; Chen, Yao; Yang, Yang; Zhong, Jie; Liu, Lijuan

    2013-12-01

    Huoxue Rongluo Tablet was made of tall gastrodis tuber, dahurian angelica root, honeysuckle stem, grassleaf sweetflag rhizome, common flowering quince fruit, figwort root, red peony root and peach seed at a ratio of 3:2:6:2:3:3:3:3. Huoxue Rongluo Tablet is a well-established and common pre-scription for the treatment of cerebral infarction. In this study, a rat model of cerebral ischemia was established and the animals were intragastrically administered Huoxue Rongluo Tablet. This treat-ment reduced infarct volume, decreased matrix metalloproteinase-9 expression, and improved neurological function. Moreover, the effects of Huoxue Rongluo Tablet were better than those of buflomedil pyridoxal phosphate. These results indicate that Huoxue Rongluo Tablet is effective in treating cerebral infarction by regulating matrix metalloproteinase-9 protein expression. PMID:25206642

  7. Green tea extracts reduce adipogenesis by decreasing expression of transcription factors C/EBPα and PPARγ

    PubMed Central

    Yang, Xiuling; Yin, Lei; Li, Tang; Chen, Zhihong

    2014-01-01

    Objectives: This study is to determine if green tea (Camellia sinensis) extracts (GTE) affects adipogenesis and further investigate the related molecular mechanisms. Methods: Patients with metabolic syndrome were recruited in this study. Of them, 70 patients received GTE and 64 received water to serve as the control group. The human serum adiponectin, visfatin, and leptin concentrations were determined by enzyme-linked immunosorbent assay. Adipogenesis of 3T3-L1 preadipocytes was induced with reagents and then the cells were treated with GTE. The lipids were stained with Oil Red O for analysis of adipogenesis of 3T3-L1 preadipocytes. The 3T3-L1 preadipocytes were treated with increasing concentrations (0.2-0.5%, w/v) of GTE for 2 days and the cell viability was determined by MTT assay. Reverse transcription real-time PCR and immunoblotting assays were performed to determine RNA and protein levels of relative molecules. Results: GTE increases the serum concentrations of adiponectin but decreases visfatin levels in patients received GTE. The leptin concentrations in serum were not significantly affected. The GTE reduces the adipogenesis-induced lipid accumulation in 3T3-L1 preadipocytes. GTE decreases the mRNA and protein expression of adipogenic transcription factors C/EBPα and PPARγ in 3T3-L1 cells. Expression levels of the adipocyte-specific genes encoding adipocyte protein 2, lipoprotein lipase, and glucose transporter 4 were also decreased by GTE. Furthermore, it was found that GTE reduces phosphorylation of Akt during adipocyte differentiation. Conclusions: GTE reduces adipogenesis by decreasing expression of transcription factors C/EBPα and PPARγ by reduction of phosphorylation of Akt during adipocyte differentiation. PMID:25663987

  8. Modified Citrus Pectin Reduces Galectin-3 Expression and Disease Severity in Experimental Acute Kidney Injury

    PubMed Central

    Kolatsi-Joannou, Maria; Price, Karen L.; Winyard, Paul J.; Long, David A.

    2011-01-01

    Galectin-3 is a β-galactoside binding lectin with roles in diverse processes including proliferation, apoptosis, inflammation and fibrosis which are dependent on different domains of the molecule and subcellular distribution. Although galectin-3 is known to be upregulated in acute kidney injury, the relative importance of its different domains and functions are poorly understood in the underlying pathogenesis. Therefore we experimentally modulated galectin-3 in folic acid (FA)-induced acute kidney injury utilising modified citrus pectin (MCP), a derivative of pectin which can bind to the galectin-3 carbohydrate recognition domain thereby predominantly antagonising functions linked to this role. Mice were pre-treated with normal or 1% MCP-supplemented drinking water one week before FA injection. During the initial injury phase, all FA-treated mice lost weight whilst their kidneys enlarged secondary to the renal insult; these gross changes were significantly lessened in the MCP group but this was not associated with significant changes in galectin-3 expression. At a histological level, MCP clearly reduced renal cell proliferation but did not affect apoptosis. Later, during the recovery phase at two weeks, MCP-treated mice demonstrated reduced galectin-3 in association with decreased renal fibrosis, macrophages, pro-inflammatory cytokine expression and apoptosis. Other renal galectins, galectin-1 and -9, were unchanged. Our data indicates that MCP is protective in experimental nephropathy with modulation of early proliferation and later galectin-3 expression, apoptosis and fibrosis. This raises the possibility that MCP may be a novel strategy to reduce renal injury in the long term, perhaps via carbohydrate binding-related functions of galectin-3. PMID:21494626

  9. Micro-structuring of polycarbonate-urethane surfaces in order to reduce platelet activation and adhesion.

    PubMed

    Clauser, Johanna; Gester, Kathrin; Roggenkamp, Jan; Mager, Ilona; Maas, Judith; Jansen, Sebastian V; Steinseifer, Ulrich

    2014-01-01

    In the development of new hemocompatible biomaterials, surface modification appears to be a suitable method in order to reduce the thrombogenetic potential of such materials. In this study, polycarbonate-urethane (PCU) tubes with different surface microstructures to be used for aortic heart valve models were investigated with regard to the thrombogenicity. The surface structures were produced by using a centrifugal casting process for manufacturing PCU tubes with defined casting mold surfaces which are conferred to the PCU surface during the process. Tubes with different structures defined by altering groove widths were cut into films and investigated under dynamic flow conditions in contact with porcine blood. The analysis was carried out by laser scanning microscopy which allowed for counting various morphological types of platelets with regard to the grade of activation. The comparison between plain and shaped PCU samples showed that the surface topography led to a decline of the activation of the coagulation cascade and thus to the reduction of the fibrin synthesis. Comparing different types of structures revealed that smooth structures with a small groove width (d ~ 3 μm) showed less platelet activation as well as less adhesion in contrast to a distinct wave structure (d ~ 90 μm). These results prove surface modification of polymer biomaterials to be a suitable method for reducing thrombogenicity and hence give reason for further alterations and improvements. PMID:24484511

  10. Arsenic transport between surface and groundwater in a moderately reducing zone: Geochemical approach

    NASA Astrophysics Data System (ADS)

    Khaska, Mahmoud; Le Gal La Salle, Corinne; Verdoux, Patrick

    2015-04-01

    Arsenic contamination represents a major risk to human health as one of the most prominent environmental causes of cancer mortality. Mining activities, particularly those involving arsenic rich ores have an impact on the environment and on human health that may persist for many decades after mine closure. The relationships between As released from alluvial aquifer in the vicinity of the sulfide-rich mine dumps was demonstrated with geochemical and isotopic tracers (major and traces elements, 87Sr/86Sr, 18O, 2H). Strontium isotopes were used to trace the transport of As downstream from a As rich tailing dam. Increasing As and Fe concentrations in surface water are explained by As release associated with alluvial groundwater discharge to the stream. This process occurs in a moderately reduced section of the stream downgradient from the sulfide-rich tailing dam. High As, total Fe and low Eh in groundwater confirm the discharge of alluvial groundwater and explain its impact on surface water. Transport of As between surface and groundwater can be described as follows: 1- Subsurface moderately reducing conditions prevail in groundwater downgradient from the tailing dams. This suggests a flux of reduced water from sulfide-rich tailing dams which is characterized by its high As and Fe content resulting from the reduction of Fe-sulfides. 2- Upon mixing with surface water, oxidizing conditions prevails and precipitate as Fe hydroxide on the stream bed. As and Sr subsequently adsorbed on the Fe -oxyhydroxide surface. This process contributes to the immobilization of As in surface water. Remaining dissolved As in surface water can be re-introduced in alluvial groundwater downstream of the reducing zone.

  11. Reduced sputum expression of interferon-stimulated genes in severe COPD

    PubMed Central

    Hilzendeger, Clarissa; da Silva, Jane; Henket, Monique; Schleich, Florence; Corhay, Jean Louis; Kebadze, Tatiana; Edwards, Michael R; Mallia, Patrick; Johnston, Sebastian L; Louis, Renaud

    2016-01-01

    Background Exacerbations of COPD are frequent and commonly triggered by respiratory tract infections. The purpose of our study was to investigate innate immunity in stable COPD patients. Methods Induced sputum was collected from 51 stable consecutive COPD patients recruited from the COPD Clinic of CHU Liege and 35 healthy subjects. Expression of interferons beta (IFN-β) and lambda1 (IL-29), IFN-stimulated genes (ISGs) MxA, OAS, and viperin were measured in total sputum cells by reverse transcription quantitative polymerase chain reaction (RT-qPCR). The presence of Picornaviruses was assessed by RT-PCR, while potential pathogenic microorganisms (PPM) were identified by sputum bacteriology. Results Expression of IL-29 was found in 16 of 51 COPD patients (31%) and in nine of 35 healthy subjects (26%), while IFN-β was detected in six of 51 COPD patients (12%) and in two of 35 healthy subjects (6%). ISGs were easily detectable in both groups. In the whole group of COPD patients, OAS expression was decreased (P<0.05), while that of viperin was increased (P<0.01) compared to healthy subjects. No difference was found with respect to MxA. COPD patients from group D of Global Initiative for Chronic Obstructive Lung Disease (GOLD) had reduced expression of all three ISGs (P<0.01 for MxA, P<0.05 for OAS, and P<0.01 for viperin) as compared to those of group B patients. Picornaviruses were detected in eight of 51 (16%) COPD patients vs four of 33 (12%) healthy subjects, while PPM were detected in seven of 39 (18%) COPD patients and associated with raised sputum neutrophil counts. IFN-β expression was raised when either picornavirus or PPM were detected (P=0.06), but no difference was seen regarding IL-29 or ISGs. Conclusion ISGs expression was reduced in severe COPD that may favor exacerbation and contribute to disease progress by altering response to infection. PMID:27418822

  12. Reducing Ice Adhesion on Nonsmooth Metallic Surfaces: Wettability and Topography Effects.

    PubMed

    Ling, Edwin Jee Yang; Uong, Victor; Renault-Crispo, Jean-Sébastien; Kietzig, Anne-Marie; Servio, Phillip

    2016-04-01

    The effects of ice formation and accretion on external surfaces range from being mildly annoying to potentially life-threatening. Ice-shedding materials, which lower the adhesion strength of ice to its surface, have recently received renewed research attention as a means to circumvent the problem of icing. In this work, we investigate how surface wettability and surface topography influence the ice adhesion strength on three different surfaces: (i) superhydrophobic laser-inscribed square pillars on copper, (ii) stainless steel 316 Dutch-weave meshes, and (iii) multiwalled carbon nanotube-covered steel meshes. The finest stainless steel mesh displayed the best performance with a 93% decrease in ice adhesion relative to polished stainless steel, while the superhydrophobic square pillars exhibited an increase in ice adhesion by up to 67% relative to polished copper. Comparisons of dynamic contact angles revealed little correlation between surface wettability and ice adhesion. On the other hand, by considering the ice formation process and the fracture mechanics at the ice-substrate interface, we found that two competing mechanisms governing ice adhesion strength arise on nonplanar surfaces: (i) mechanical interlocking of the ice within the surface features that enhances adhesion, and (ii) formation of microcracks that act as interfacial stress concentrators, which reduce adhesion. Our analysis provides insight toward new approaches for the design of ice-releasing materials through the use of surface topographies that promote interfacial crack propagation. PMID:26953827

  13. Multiple imaging techniques demonstrate the manipulation of surfaces to reduce bacterial contamination and corrosion.

    PubMed

    Arnold, J W; Boothe, D H; Suzuki, O; Bailey, G W

    2004-12-01

    Surface imaging techniques were combined to determine appropriate manipulation of technologically important surfaces for commercial applications. The complementarity of the microscopy methods, scanning electron microscopy, electron probe microanalysis and atomic force microscopy assessed and correlated form and function of the surface modifications. Stainless steel disks (1 cm in diameter) were laser-cut from the same sheets of stainless steel and treated by electropolishing or left untreated for controls. Each treatment was analysed separately using each technique. First, the disks were examined by visual inspection and electron probe microanalysis for surface characteristics and elemental composition, respectively. Aliquots of bacterial suspensions (saline rinses of poultry carcasses from a commercial broiler processing plant) were then diluted in broth and monitored for growth by spectrophotometry. Stainless steel disks (1 cm in diameter) were added and the cultures were grown to sufficient density to allow attachment of bacterial cells to test surfaces. Relative differences in the surface morphology shown by atomic force microscopy, including Z ranges, roughness and other measurements, corresponded by treatment with the differences in reduction of bacterial counts shown by scanning electron microscopy. A model of wet-processing conditions tested the effects of corrosive treatment of surfaces. Less bacterial attachment occurred after corrosive treatment on controls and electropolished samples. Electropolishing significantly reduced bacterial numbers and the effects of corrosive action compared to the controls. Thus, the multiple imaging techniques showed that engineered changes on stainless steel surfaces improved the resistance of the surface finish to bacterial attachment, biofilm formation, and corrosive action. PMID:15566492

  14. Reduced Expression of Antimicrobial PLUNC Proteins in Nasal Polyp Tissues of patients with Chronic Rhinosinusitis

    PubMed Central

    Seshadri, Sudarshan; Lin, David C.; Rosati, Mariel; Carter, Roderick G.; Norton, James E.; Suh, Lydia; Kato, Atsushi; Chandra, Rakesh K.; Harris, Kathleen E.; Chu, Hong Wei; Peters, Anju T.; Tan, Bruce K.; Conley, David B.; Grammer, Leslie C.; Kern, Robert C.; Schleimer, Robert P.

    2012-01-01

    Background Chronic rhinosinusitis (CRS) is a disease characterized by inflammation of the nasal mucosa and paranasal sinuses. This inflammation may result in part from decreased epithelial barrier and innate immune responses, leading to frequent bacterial and fungal colonization. The objectives of this study were to investigate the expression of innate immune proteins of the Palate Lung and Nasal epithelium Clone (PLUNC) family in patients with CRS. Methods Nasal tissue samples were collected from control subjects and CRS patients with and without nasal polyps. Expression of the members of the PLUNC family was analyzed by real-time PCR. Expression of SPLUNC1 and LPLUNC2 proteins was analyzed by ELISA, immunoblot and immunohistochemical analysis. Results Levels of mRNA for most of the members of the PLUNC family were profoundly reduced in nasal polyps (NPs) compared to uncinate tissue from control subjects or CRS patients. LPLUNC2 and SPLUNC1 proteins were decreased in NPs of CRS patients compared to uncinate tissue from control subjects. Immunohistochemical data revealed that within submucosal glands of sinonasal tissues, SPLUNC1 and LPLUNC2 were differentially expressed, in serous and mucous cells, respectively. The decrease in expression of these molecules is probably explained by a decrease in the number of glands in NPs as revealed by correlations with levels of the glandular marker lactoferrin. Conclusions Decreased SPLUNC1 and LPLUNC2 in NPs reflects a profound decrease in the number of submucosal glands. Decreased glands may lead to a localized defect in the production and release of glandular innate defense molecules. PMID:22676062

  15. Hepatic AQP9 expression in male rats is reduced in response to PPARα agonist treatment.

    PubMed

    Lebeck, Janne; Cheema, Muhammad Umar; Skowronski, Mariusz T; Nielsen, Søren; Praetorius, Jeppe

    2015-02-01

    The peroxisome proliferator receptor α (PPARα) is a key regulator of the hepatic response to fasting with effects on both lipid and carbohydrate metabolism. A role in hepatic glycerol metabolism has also been found; however, the results are somewhat contradictive. Aquaporin 9 (AQP9) is a pore-forming transmembrane protein that facilitates hepatic uptake of glycerol. Its expression is inversely regulated by insulin in male rodents, with increased expression during fasting. Previous results indicate that PPARα plays a crucial role in the induction of AQP9 mRNA during fasting. In the present study, we use PPARα agonists to explore the effect of PPARα activation on hepatic AQP9 expression and on the abundance of enzymes involved in glycerol metabolism using both in vivo and in vitro systems. In male rats with free access to food, treatment with the PPARα agonist WY 14643 (3 mg·kg(-1)·day(-1)) caused a 50% reduction in hepatic AQP9 abundance with the effect being restricted to AQP9 expressed in periportal hepatocytes. The pharmacological activation of PPARα had no effect on the abundance of GlyK, whereas it caused an increased expression of hepatic GPD1, GPAT1, and L-FABP protein. In WIF-B9 and HepG2 hepatocytes, both WY 14643 and another PPARα agonist GW 7647 reduced the abundance of AQP9 protein. In conclusion, pharmacological PPARα activation results in a marked reduction in the abundance of AQP9 in periportal hepatocytes. Together with the effect on the enzymatic apparatus for glycerol metabolism, our results suggest that PPARα activation in the fed state directs glycerol into glycerolipid synthesis rather than into de novo synthesis of glucose. PMID:25477377

  16. Soluble calcium amendment: Co-Application with poultry litter to reduce P loss following surface application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper will discuss the utilization of gypsum (CaSO4 .2H2O) to reduce P losses from surface runoff when poultry litter is used as a fertilizer source in agriculture. Utilization of poultry litter as a fertilizer source is common in regions with intense poultry production. While poultry litter ha...

  17. 40 CFR 52.253 - Metal surface coating thinner and reducer.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... described in 40 CFR part 81, dated July 1, 1979, except as follows: (1) In the following portions of the... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Metal surface coating thinner and... coating thinner and reducer. (a) All terms defined in § 52.254 are used herein with the meanings...

  18. Soil solarization reduces Escherichia coli O157:H7 on cattle feedlot pen surfaces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Soils at the feedlot pen surface are a source for transmission of Escherichia coli O157:H7, and therefore a target for control measures to reduce this pathogen in cattle. Soil solarization is a preplanting technique used in food and ornamental crop production, which utilizes solar en...

  19. Airfoil-shaped micro-mixers for reducing fouling on membrane surfaces

    SciTech Connect

    Ho, Clifford K; Altman, Susan J; Clem, Paul G; Hibbs, Michael; Cook, Adam W

    2012-10-23

    An array of airfoil-shaped micro-mixers that enhances fluid mixing within permeable membrane channels, such as used in reverse-osmosis filtration units, while minimizing additional pressure drop. The enhanced mixing reduces fouling of the membrane surfaces. The airfoil-shaped micro-mixer can also be coated with or comprised of biofouling-resistant (biocidal/germicidal) ingredients.

  20. Waste Foundry Sand Soil Amendment to Reduce Atrazine Loading to Surface Runoff

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of experiments was conducted to evaluate the potential for surface applied foundry sand (FS) waste material to reduce atrazine in runoff water from fields having atrazine-based weed management. In the first experiment, the ability of several FSs to remove atrazine from the water column was ...

  1. Surface adhesive forces: a metric describing the drag-reducing effects of superhydrophobic coatings.

    PubMed

    Cheng, Mengjiao; Song, Mengmeng; Dong, Hongyu; Shi, Feng

    2015-04-01

    Nanomaterials with superhydrophobic properties are promising as drag-reducing coatings. However, debates regarding whether superhydrophobic surfaces are favorable for drag reduction require further clarification. A quantified water adhesive force measurement is proposed as a metric and its effectiveness demonstrated using three typical superhydrophobic coatings on model ships with in situ sailing tests. PMID:25418808

  2. Method and apparatus for reducing the drag of flows over surfaces

    NASA Technical Reports Server (NTRS)

    Keefe, Laurence R. (Inventor)

    1998-01-01

    An apparatus, and its accompanying method, for reducing the drag of flows over a surface includes arrays of small disks and sensors. The arrays are embedded in the surface and may extend above, or be depressed below, the surface, provided they remain hydraulically smooth either when operating or when inactive. The disks are arranged in arrays of various shapes, and spaced according to the cruising speed of the vehicle on which the arrays are installed. For drag reduction at speeds of the order of 30 meters/second, preferred embodiments include disks that are 0.2 millimeter in diameter and spaced 0.4 millimeter apart. For drag reduction at speeds of the order of 300 meters/second, preferred embodiments include disks that are 0.045 millimeter in diameter and spaced 0.09 millimeter apart. Smaller and larger dimensions for diameter and spacing are also possible. The disks rotate in the plane of the surface, with their rotation axis substantially perpendicular to the surface. The rotating disks produce velocity perturbations parallel to the surface in the overlying boundary layer. The sensors sense the flow at the surface and connect to control circuitry that adjusts the rotation rates and duty cycles of the disks accordingly. Suction and blowing holes can be interspersed among, or made coaxial with, the disks for creating general three-component velocity perturbations in the near-surface region. The surface can be a flat, planar surface or a nonplanar surface, such as a triangular riblet surface. The present apparatus and method have potential applications in the field of aeronautics for improving performance and efficiency of commercial and military aircraft, and in other industries where drag is an obstacle, including gas and oil delivery through long-haul pipelines.

  3. Apoptosis is associated with reduced expression of complement regulatory molecules, adhesion molecules and other receptors on polymorphonuclear leucocytes: functional relevance and role in inflammation.

    PubMed Central

    Jones, J; Morgan, B P

    1995-01-01

    Human polymorphonuclear leucocytes (PMN) express proteins that protect them from damage by homologous complement. Protection may be particularly important when these cells migrate to inflammatory sites where complement activation is taking place. Resolution of inflammation involves removal of these PMN. The major mechanism of removal is likely to involve PMN apoptosis followed by recognition and engulfment by macrophages. However, little attention has been paid to the possible relevance of apoptosis to PMN susceptibility to immune effectors. Here we describe a reduction in cell surface expression of two complement regulatory proteins, CD59, an inhibitor of the membrane attack complex and CD55 (decay accelerating factor), an inhibitor of the C3/C5 convertase, on a subpopulation of PMN aged in culture. Loss of these proteins, both attached to the membrane by glycosyl phosphatidylinositol (GPI) anchors, correlated closely with the appearance of apoptotic morphology. We also observed a marked reduction in expression of the GPI-anchored molecule CD16 on apoptotic PMN. Reduced expression of membrane proteins was not confined to those anchored through GPI--several transmembrane molecules including CD11a CD11b and CD18 were also reduced on apoptotic PMN, whilst other were little changed (CD35, CD46). The precipitous fall in CD16 surface expression on PMN was not specific for apoptosis--in vitro incubation of PMN with lipopolysaccharide-inhibited apoptosis but caused a reduction in CD16 expression to 'apoptotic' levels. Images Figure 2 PMID:8567034

  4. Hydrocortisone Reduces Toll-Like Receptor 4 Expression on Peripheral CD14+ Monocytes in Patients Undergoing Percutanoues Coronary Intervention

    PubMed Central

    Bagheri, Bahador; Sohrabi, Bahram; Movassaghpour, Ali Akbar; Mashayekhi, Simin; Garjani, Afagh; Shokri, Mehriar; Pezeshkian, Masoud; Garjani, Alireza

    2014-01-01

    Bacground: Evidence from several lines of investigations suggests that Toll-like receptor 4 (TLR4) is involved in atherosclerosis as a bridge between innate and acquired immunity. Percutaneous coronary intervention (PCI) can trigger inflammation through activation of human TLR4 (hTLR4) on monocytes. Hydrocortisone as an anti-inflammatory and immuno-suppressant agent has multiple mechanisms of action. In this study, we aimed at assessing the effects of hydrocortisone on monocyte expression and activity of hTLR4 in patients underwent PCI. Methods: Blood samples were taken from a total of 71 patients with chronic stable angina who were scheduled for a PCI, before the intervention. Thirty patients received 100 mg hydrocortisone prior to the procedure. Control group was composed of 41 patients underwent PCI without receiving hydrocortisone. Blood collection was repeated 2 and 4 h after PCI. The expression of hTLR4 on the surface of CD14+ monocytes and the serum levels of TNF-α and IL-1β were measured using flowcytometry and Sandwich ELISA. Results: Compared with controls, hydrocortisone significantly reduced monocyte expression of hTLR4 in test group (P<0.01). In addition, it had a significant effect on reduction of serum concentrations of TNF-α and IL-1β in test group in a time-dependent manner (P<0.01). Conclusion: In this study, hydrocortisone was able to reduce the hTLR4/CD14 positive monocytes and its related pro-inflammatory cytokines, thus it can decrease inflammatory responses following PCI. PMID:24518547

  5. Carbohydrate Coating Reduces Adhesion of Biofilm-Forming Bacillus subtilis to Gold Surfaces

    PubMed Central

    Kesel, S.; Mader, A.; Seeberger, P. H.; Lieleg, O.

    2014-01-01

    The growth of bacterial biofilms in pipes and food tanks causes severe problems in industry. Biofilms growing on medical implants or catheters are of great concern, as they can cause serious infections and decrease the functionality of the medical device. The prevention of bacterial adhesion—the first step in colonization and biofilm formation—is therefore very important. Current research comprises alterations in surface properties, the prevention of adhesin biosynthesis, inhibition with receptor analogs, or the development of anti-adhesive vaccines. We present a new approach that allows us to study bacterial adhesion with high sensitivity in real-time while testing several different surfaces in parallel. Using the cantilever-array technique we demonstrate that coating of gold surfaces with mono- or disaccharides results in a reduction of the bacterial adhesion of the biofilm-forming bacterium Bacillus subtilis NCIB 3610 to these gold surfaces. This reduction in bacterial adhesion is independent of the studied carbohydrate. Using several mutant strains, we investigate the underlying molecular interactions, and our results suggest that adhesion to gold surfaces is mediated by thiol groups present in proteins of the bacterial cell membrane or biofilm matrix proteins expressed at low levels by the wild-type strain. Furthermore, our data indicate that the adhesion of B. subtilis NCIB 3610 to carbohydrate-coated gold surfaces is facilitated by interactions between carbohydrates installed on the cantilever gold surface and an exopolysaccharide expressed by this strain. Understanding general and specific contributions of molecular interactions mediating bacterial adhesion will enable its prevention in the future. PMID:25038098

  6. Impact of a Reducing Agent on the Dynamic Surface Properties of Lysozyme Solutions.

    PubMed

    Tihonov, Michael M; Kim, Viktoria V; Noskov, Boris A

    2016-05-01

    Disulfide bond shuffling in the presence of the reducing agents dithiothreitol (DTT) or β-mercaptoethanol (BME) strongly affects the surface properties of lysozyme solutions. The addition of 0.32 mM DTT substantially alters the kinetic dependencies of the dynamic surface elasticity and surface tension relative to those of pure protein solutions. The significant increase in the dynamic surface elasticity likely relates to the cross-linking between lysozyme molecules and the formation of a dense layer of protein globules stabilized by intermolecular disulfide bonds at the liquid/gas interface. This effect differs from the previously described influence of chaotropic denaturants, such as guanidine hydrochloride (GuHCl) and urea, on the surface properties of lysozyme solutions. If both chaotropic and reducing agents are added to protein solutions simultaneously, their effects become superimposed. In the case of mixed lysozyme/GuHCl/DTT solutions, the dynamic surface elasticity near equilibrium decreases as the GuHCl concentration increases because of the gradual loosening of the cross-linked layer of protein globules but remains much higher than that of lysozyme/GuHCl solutions. PMID:27086995

  7. Deafness and permanently reduced potassium channel gene expression and function in hypothyroid Pit1dw mutants

    PubMed Central

    Mustapha, Mirna; Fang, Qing; Gong, Tzy-Wen; Dolan, David F.; Raphael, Yehoash; Camper, Sally A.; Duncan, R. Keith

    2012-01-01

    The absence of thyroid hormone (TH) during late gestation and early infancy can cause irreparable deafness in both humans and rodents. A variety of rodent models have been utilized in an effort to identify the underlying molecular mechanism. Here, we characterize a mouse model of secondary hypothyroidism, pituitary transcription factor 1 (Pit1dw), which has profound, congenital deafness that is rescued by oral TH replacement. These mutants have tectorial membrane abnormalities, including a prominent Hensen's stripe, elevated β-tectorin composition, and disrupted striated-sheet matrix. They lack distortion product otoacoustic emissions and cochlear microphonic responses, and exhibit reduced endocochlear potentials, suggesting defects in outer hair cell function and potassium recycling. Auditory system and hair cell physiology, histology and anatomy studies reveal novel defects of hormone deficiency related to deafness: (1) permanently impaired expression of KCNJ10 in the stria vascularis of Pit1dw mice, which likely contributes to the reduced endocochlear potential, (2) significant outer hair cell loss in the mutants, which may result from cellular stress induced by the lower KCNQ4 expression and current levels in Pit1dw mutant outer hair cells and (3) sensory and strial cell deterioration, which may have implications for thyroid hormone dysregulation in age related hearing impairment. In summary, we suggest that these defects in outer hair cell and strial cell function are important contributors to the hearing impairment in Pit1dw mice. PMID:19176829

  8. Decreased Bdnf expression and reduced social behavior in periadolescent rats following prenatal stress.

    PubMed

    Berry, Alessandra; Panetta, Pamela; Luoni, Alessia; Bellisario, Veronica; Capoccia, Sara; Riva, Marco Andrea; Cirulli, Francesca

    2015-04-01

    Prenatal stress (PNS) is a risk factor for the development of neuropsychiatric disorders. This study was aimed at assessing, in a rodent model, changes in gene expression profiles and behavioral output as a result of PNS, during periadolescence, a critical developmental period for the onset of psychopathology. Social behavior was studied in a standardized social interaction paradigm and the expression of Brain-Derived Neurotrophic Factor (Bdnf), a marker of neuronal plasticity, and of inhibitory and excitatory mechanisms (Na(+)-K(+)-2Cl(-) and K(+)-Cl(-) cotransporters ratio, NKCC1/KCC2) was analyzed. Results indicate that PNS reduced Bdnf transcripts while increasing the NKCC1/KCC2 ratio, primarily in the hippocampus. In the prefrontal cortex, changes in Bdnf were found to be gender-dependent. These effects were accompanied by reduced levels of affiliative and investigative social behaviors. Interestingly, interaction with non-stressed subjects was able to improve sociality in PNS rats suggesting that the social environment could be exploited for therapeutic intervention. PMID:25783782

  9. Phenanthrene exposure induces cardiac hypertrophy via reducing miR-133a expression by DNA methylation

    PubMed Central

    Huang, Lixing; Xi, Zhihui; Wang, Chonggang; Zhang, Youyu; Yang, Zhibing; Zhang, Shiqi; Chen, Yixin; Zuo, Zhenghong

    2016-01-01

    Growing evidence indicates that there is an emerging link between environmental pollution and cardiac hypertrophy, while the mechanism is unclear. The objective of this study was to examine whether phenanthrene (Phe) could cause cardiac hypertrophy, and elucidate the molecular mechanisms involved. We found that: 1) Phe exposure increased the heart weight and cardiomyocyte size of rats; 2) Phe exposure led to enlarged cell size, and increased protein synthesis in H9C2 cells; 3) Phe exposure induced important markers of cardiac hypertrophy, such as atrial natriuretic peptide, B-type natriuretic peptide, and c-Myc in H9C2 cells and rat hearts; 4) Phe exposure perturbed miR-133a, CdC42 and RhoA, which were key regulators of cardiac hypertrophy, in H9C2 cells and rat hearts; 5) Phe exposure induced DNA methyltransferases (DNMTs) in H9C2 cells and rat hearts; 6) Phe exposure led to methylation of CpG sites within the miR-133a locus and reduced miR-133a expression in H9C2 cells; 7) DNMT inhibition and miR-133a overexpression could both alleviate the enlargement of cell size and perturbation of CdC42 and RhoA caused by Phe exposure. These results indicated that Phe could induce cardiomyocyte hypertrophy in the rat and H9C2 cells. The mechanism might involve reducing miR-133a expression by DNA methylation. PMID:26830171

  10. Reducing the expression of implicit stereotypes: reflexive control through implementation intentions.

    PubMed

    Mendoza, Saaid A; Gollwitzer, Peter M; Amodio, David M

    2010-04-01

    The authors tested the effectiveness of implementation intentions as a strategy for limiting the behavioral expression of implicit stereotypes. Implementation intentions are if-then plans that link an intended response to an anticipated situational cue, thereby enabling a reflexive form of control. The authors examined whether two different types of implementation intentions could improve response accuracy on the Shooter Task, a reaction time measure of implicit stereotyping. In Study 1, participants used a distraction-inhibiting implementation intention designed to engage control over the perception of goal-irrelevant stimuli (e.g., race). In Study 2, participants used a response-facilitating implementation intention designed to promote goal-directed action. Across studies, implementation intentions improved accuracy, thereby limiting the behavioral expression of implicit stereotypes. Furthermore, process dissociation analyses indicated that the distraction-inhibiting implementation intention increased controlled processing while reducing automatic stereotype activation, whereas the response-facilitating implementation intention increased only controlled processing. Implications for goal strategy approaches to reducing prejudice are discussed. PMID:20363905

  11. Reduced leu operon expression in a miaA mutant of Salmonella typhimurium.

    PubMed Central

    Blum, P H

    1988-01-01

    Salmonella typhimurium miaA mutants lacking the tRNA base modification cis-2-methylthioribosylzeatin (ms2io6A) were examined and found to be sensitive to a variety of chemical oxidants and unable to grow aerobically at 42 degrees C in a defined medium. Leucine supplementation suppressed both of these phenotypes, suggesting that leucine synthesis was defective. Intracellular levels of leucine decreased 40-fold in mutant strains after a shift from 30 to 42 degrees C during growth, and expression of a leu-lacZ transcriptional fusion ceased. Steady-state levels of leu mRNA were also significantly reduced during growth at elevated temperatures. Failure of miaA mutant leu-lacZ expression to be fully derepressed during L-leucine limitation at 30 degrees C and suppression of the miaA mutation by a mutation in the S. typhimurium leu attenuator suggests that translational control of the transcription termination mechanism regulating leu expression is defective. Since the S. typhimurium miaA mutation was also suppressed by the Escherichia coli leu operon in trans, phenotypic differences between E. coli and S. typhimurium miaA mutants may result from a difference between their respective leu operons. Images PMID:3141379

  12. Herpes simplex ICP27 mutant viruses exhibit reduced expression of specific DNA replication genes.

    PubMed Central

    Uprichard, S L; Knipe, D M

    1996-01-01

    Herpes simplex virus type 1 mutants with certain lesions in the ICP27 gene show a 5- to 10-fold reduction in viral DNA synthesis. To determine how ICP27 promotes amplification of viral DNA, we examined the synthesis, accumulation, and stability of the essential viral replication proteins and steady-state levels of the replication gene transcripts throughout the course of ICP27 mutant virus infections. These studies reveal that in the absence of ICP27, expression of the UL5, UL8, UL52, UL9, UL42, and UL30 genes is significantly reduced at the level of mRNA accumulation. In contrast to that of these beta genes, ICP8 expression is unaltered in mutant virus-infected cells, indicating that ICP27 selectively stimulates only a subset of herpes simplex virus beta genes. Analysis of multiple ICP27 mutant viruses indicates a quantitative correlation between the ability of these mutants to replicate viral DNA and the level of replication proteins produced by each mutant. Therefore, we conclude that the primary defect responsible for restricted viral DNA synthesis in cells infected with ICP27 mutants is insufficient expression of most of the essential replication genes. Of further interest, this analysis also provides new information about the structure of the UL52 gene transcripts. PMID:8627723

  13. Mimecan, a Hormone Abundantly Expressed in Adipose Tissue, Reduced Food Intake Independently of Leptin Signaling

    PubMed Central

    Cao, Huang-Ming; Ye, Xiao-Ping; Ma, Jun-Hua; Jiang, He; Li, Sheng-Xian; Li, Rong-Ying; Li, Xue-Song; Guo, Cui-Cui; Wang, Zhi-Quan; Zhan, Ming; Zuo, Chun-Lin; Pan, Chun-Ming; Zhao, Shuang-Xia; Zheng, Cui-Xia; Song, Huai-Dong

    2015-01-01

    Adipokines such as leptin play important roles in the regulation of energy metabolism, particularly in the control of appetite. Here, we describe a hormone, mimecan, which is abundantly expressed in adipose tissue. Mimecan was observed to inhibit food intake and reduce body weight in mice. Intraperitoneal injection of a mimecan-maltose binding protein (-MBP) complex inhibited food intake in C57BL/6J mice, which was attenuated by pretreatment with polyclonal antibody against mimecan. Notably, mimecan-MBP also induced anorexia in Ay/a and db/db mice. Furthermore, the expression of interleukin (IL)-1β and IL-6 was up-regulated in the hypothalamus by mimecan-MBP, as well as in N9 microglia cells by recombinant mouse mimecan. Taken together, the results suggest that mimecan is a satiety hormone in adipose tissue, and that mimecan inhibits food intake independently of leptin signaling by inducing IL-1β and IL-6 expression in the hypothalamus. PMID:26870797

  14. Reduced Expression of the Hyaluronan and Proteoglycan Link Proteins in Malignant Gliomas*

    PubMed Central

    Sim, Hosung; Hu, Bin; Viapiano, Mariano S.

    2009-01-01

    Malignant gliomas have a distinctive ability to infiltrate the brain parenchyma and disrupt the neural extracellular matrix that inhibits motility of axons and normal neural cells. Chondroitin sulfate proteoglycans (CSPGs) are among the major inhibitory components in the neural matrix, but surprisingly, some are up-regulated in gliomas and act as pro-invasive signals. In the normal brain, CSPGs are thought to associate with hyaluronic acid and glycoproteins such as the tenascins and link proteins to form the matrix scaffold. Here, we examined for the first time the expression of link proteins in human brain and malignant gliomas. Our results indicate that HAPLN4 and HAPLN2 are the predominant members of this family in the adult human brain but are strongly reduced in the tumor parenchyma. To test if their absence was related to a pro-invasive gain of function of CSPGs, we expressed HAPLN4 in glioma cells in combination with the CSPG brevican. Surprisingly, HAPLN4 increased glioma cell adhesion and migration and even potentiated the motogenic effect of brevican. Further characterization revealed that HAPLN4 expressed in glioma cells was largely soluble and did not reproduce the strong, hyaluronan-independent association of the native protein to brain subcellular membranes. Taken together, our results suggest that the tumor parenchyma is rich in CSPGs that are not associated to HAPLNs and could instead interact with other extracellular matrix proteins produced by glioma cells. This dissociation may contribute to changes in the matrix scaffold caused by invasive glioma cells. PMID:19633295

  15. Nonspecific transcription factor binding can reduce noise in the expression of downstream proteins

    NASA Astrophysics Data System (ADS)

    Soltani, M.; Bokes, P.; Fox, Z.; Singh, A.

    2015-10-01

    Transcription factors (TFs) interact with a multitude of binding sites on DNA and partner proteins inside cells. We investigate how nonspecific binding/unbinding to such decoy binding sites affects the magnitude and time-scale of random fluctuations in TF copy numbers arising from stochastic gene expression. A stochastic model of TF gene expression, together with decoy site interactions is formulated. Distributions for the total (bound and unbound) and free (unbound) TF levels are derived by analytically solving the chemical master equation under physiologically relevant assumptions. Our results show that increasing the number of decoy binding sides considerably reduces stochasticity in free TF copy numbers. The TF autocorrelation function reveals that decoy sites can either enhance or shorten the time-scale of TF fluctuations depending on model parameters. To understand how noise in TF abundances propagates downstream, a TF target gene is included in the model. Intriguingly, we find that noise in the expression of the target gene decreases with increasing decoy sites for linear TF-target protein dose-responses, even in regimes where decoy sites enhance TF autocorrelation times. Moreover, counterintuitive noise transmissions arise for nonlinear dose-responses. In summary, our study highlights the critical role of molecular sequestration by decoy binding sites in regulating the stochastic dynamics of TFs and target proteins at the single-cell level.

  16. Surface properties and reduced biofouling of graft-copolymers that possess oppositely charged groups.

    PubMed

    Herzberg, Moshe; Sweity, Amer; Brami, Matan; Kaufman, Yair; Freger, Viatcheslav; Oron, Gideon; Belfer, Sophia; Kasher, Roni

    2011-04-11

    Microbial biofilms and their components present a major obstacle for ensuring the long-term effectiveness of membrane processes. Graft polymerization on membrane surfaces, in general, and grafting with oppositely charged monomers, have been shown to reduce biofouling significantly. In this study, surface forces and macromolecular properties of graft copolymers that possess oppositely charged groups were related to their potent antibiofouling behavior. Graft polymerization was performed using the negatively charged 3-sulphopropyl methacrylate (SPM) and positively charged [2-(methacryloyloxy)ethyl]-trimethylammonium (MOETMA) monomers to yield a copolymer layer on polyvinylidene fluoride (PVDF) surface. Quartz crystal microbalance with dissipation monitoring (QCM-D) technology was used to monitor the reduced adsorption of extracellular polymeric substances (EPS) extracted from a membrane bioreactor (MBR) wastewater treatment facility. Complemented measurements of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy provided evaluation of the antifouling properties of the surface. Increase in water content in grafted layer exposed to 100 mM aqueous NaCl solution was observed by QCM-D. Therefore, the grafted copolymer layer is swelled in the presence of 100 mM NaCl because of reversing of polymer self-association by counterions. Force measurements by atomic force microscopy (AFM) showed an increased repulsion between a carboxylate-modified latex (CML) particle probe and a modified PVDF surface, especially in the presence of 100 mM NaCl. The hydration and swelling of the grafted polymer layer are shown to repel EPS and reduce their adsorption. Delineating the surface properties of antifouling grafted layers may lead to the design of novel antifouling surfaces. PMID:21361342

  17. Chemical Inhibition of Kynureninase Reduces Pseudomonas aeruginosa Quorum Sensing and Virulence Factor Expression.

    PubMed

    Kasper, Stephen H; Bonocora, Richard P; Wade, Joseph T; Musah, Rabi Ann; Cady, Nathaniel C

    2016-04-15

    The opportunistic pathogen Pseudomonas aeruginosa utilizes multiple quorum sensing (QS) pathways to coordinate an arsenal of virulence factors. We previously identified several cysteine-based compounds inspired by natural products from the plant Petiveria alliacea which are capable of antagonizing multiple QS circuits as well as reducing P. aeruginosa biofilm formation. To understand the global effects of such compounds on virulence factor production and elucidate their mechanism of action, RNA-seq transcriptomic analysis was performed on P. aeruginosa PAO1 exposed to S-phenyl-l-cysteine sulfoxide, the most potent inhibitor from the prior study. Exposure to this inhibitor down-regulated expression of several QS-regulated virulence operons (e.g., phenazine biosynthesis, type VI secretion systems). Interestingly, many genes that were differentially regulated pertain to the related metabolic pathways that yield precursors of pyochelin, tricarboxylic acid cycle intermediates, phenazines, and Pseudomonas quinolone signal (PQS). Activation of the MexT-regulon was also indicated, including the multidrug efflux pump encoded by mexEF-oprN, which has previously been shown to inhibit QS and pathogenicity. Deeper investigation of the metabolites involved in these systems revealed that S-phenyl-l-cysteine sulfoxide has structural similarity to kynurenine, a precursor of anthranilate, which is critical for P. aeruginosa virulence. By supplementing exogenous anthranilate, the QS-inhibitory effect was reversed. Finally, it was shown that S-phenyl-l-cysteine sulfoxide competitively inhibits P. aeruginosa kynureninase (KynU) activity in vitro and reduces PQS production in vivo. The kynurenine pathway has been implicated in P. aeruginosa QS and virulence factor expression; however, this is the first study to show that targeted inhibition of KynU affects P. aeruginosa gene expression and QS, suggesting a potential antivirulence strategy. PMID:26785289

  18. Dienogest reduces HSD17β1 expression and activity in endometriosis.

    PubMed

    Mori, Taisuke; Ito, Fumitake; Matsushima, Hiroshi; Takaoka, Osamu; Koshiba, Akemi; Tanaka, Yukiko; Kusuki, Izumi; Kitawaki, Jo

    2015-05-01

    Endometriosis is an estrogen-dependent disease. Abnormally biosynthesized estrogens in endometriotic tissues induce the growth of the lesion and worsen endometriosis-associated pelvic pain. Dienogest (DNG), a selective progesterone receptor agonist, is widely used to treat endometriosis and efficiently relieves the symptoms. However, its pharmacological action remains unknown. In this study, we elucidated the effect of DNG on enzymes involved in local estrogen metabolism in endometriosis. Surgically obtained specimens of 23 ovarian endometriomas (OE) and their homologous endometrium (EE), ten OE treated with DNG (OE w/D), and 19 normal endometria without endometriosis (NE) were analyzed. Spheroid cultures of stromal cells (SCs) were treated with DNG and progesterone. The expression of aromatase, 17β-hydroxysteroid dehydrogenase 1 (HSD17β1), HSD17β2, HSD17β7, HSD17β12, steroid sulfatase (STS), and estrogen sulfotransferase (EST) was evaluated by real-time quantitative PCR. The activity and protein level of HSD17β1 were measured with an enzyme assay using radiolabeled estrogens and immunohistochemistry respectively. OESCs showed increased expression of aromatase, HSD17β1, STS, and EST, along with decreased HSD17β2 expression, when compared with stromal cells from normal endometria without endometriosis (NESCs) (P<0.01) or stromal cells from homologous endometrium (EESCs) (P<0.01). In OESCs, DNG inhibited HSD17β1 expression and enzyme activity at 10(-7) M (P<0.01). Results of immunohistochemical analysis displayed reduced HSD17β1 staining intensity in OE w/D (P<0.05). In conclusion, DNG exerts comprehensive inhibition of abnormal estrogen production through inhibition of aromatase and HSD17β1, contributing to a therapeutic effect of DNG on endometriosis. PMID:25767055

  19. Hypertonic saline reduces lipopolysaccharide-induced mouse brain edema through inhibiting aquaporin 4 expression

    PubMed Central

    2012-01-01

    Introduction Three percent sodium chloride (NaCl) treatment has been shown to reduce brain edema and inhibited brain aquaporin 4 (AQP4) expression in bacterial meningitis induced by Escherichia coli. Lipopolysaccharide (LPS) is the main pathogenic component of E. coli. We aimed to explore the effect of 3% NaCl in mouse brain edema induced by LPS, as well as to elucidate the potential mechanisms of action. Methods Three percent NaCl was used to treat cerebral edema induced by LPS in mice in vivo. Brain water content, IL-1β, TNFα, immunoglobulin G (IgG), AQP4 mRNA and protein were measured in brain tissues. IL-1β, 3% NaCl and calphostin C (a specific inhibitor of protein kinase C) were used to treat the primary astrocytes in vitro. AQP4 mRNA and protein were measured in astrocytes. Differences in various groups were determined by one-way analysis of variance. Results Three percent NaCl attenuated the increase of brain water content, IL-1β, TNFα, IgG, AQP4 mRNA and protein in brain tissues induced by LPS. Three percent NaCl inhibited the increase of AQP4 mRNA and protein in astrocytes induced by IL-1β in vitro. Calphostin C blocked the decrease of AQP4 mRNA and protein in astrocytes induced by 3% NaCl in vitro. Conclusions Osmotherapy with 3% NaCl ameliorated LPS-induced cerebral edema in vivo. In addition to its osmotic force, 3% NaCl exerted anti-edema effects possibly through down-regulating the expression of proinflammatory cytokines (IL-1β and TNFα) and inhibiting the expression of AQP4 induced by proinflammatory cytokines. Three percent NaCl attenuated the expression of AQP4 through activation of protein kinase C in astrocytes. PMID:23036239

  20. Decreased tumorigenicity correlates with expression of altered cell surface carbohydrates in Lec9 CHO cells.

    PubMed Central

    Ripka, J; Shin, S; Stanley, P

    1986-01-01

    To investigate a role for surface carbohydrates in cellular malignancy, 15 different glycosylation-defective CHO cell mutants were examined for their tumorigenic and metastatic capacities after subcutaneous injection into nude mice. Most of the glycosylation mutants displayed similar or slightly decreased tumorigenicity compared with parental CHO cells. Neither parental CHO cells nor any of the mutants were observed to metastasize. However, independent isolates of one mutant type, Lec9, showed a dramatic reduction in tumor formation. The altered carbohydrates expressed at the surface of Lec9 cells appeared to be responsible for their loss of tumorigenicity, because revertants for lectin resistance were able to form tumors, and a double mutant (Lec9.Lec1) that expressed a Lec1 glycosylation phenotype also formed tumors. Finally, Lec9 cells were able to form tumors in gamma-irradiated nude mice, suggesting that recognition by an irradiation-sensitive host cell(s) was responsible for their reduced tumorigenicity in untreated nude mice. PMID:3785164

  1. Yeast cell-surface expression of chitosanase from Paenibacillus fukuinensis.

    PubMed

    Fukuda, Takeshi; Isogawa, Danya; Takagi, Madoka; Kato-Murai, Michiko; Kimoto, Hisashi; Kusaoke, Hideo; Ueda, Mitsuyoshi; Suye, Shin-Ichiro

    2007-11-01

    To produce chitoorigosaccharides using chitosan, we attempted to construct Paenibacillus fukuinensis chitosanase-displaying yeast cells as a whole-cell biocatalyst through yeast cell-surface engineering. The localization of the chitosanase on the yeast cell surface was confirmed by immunofluorescence labeling of cells. The chitosanase activity of the constructed yeast was investigated by halo assay and the dinitrosalicylic acid method. PMID:17986777

  2. Understanding the Role of Wind in Reducing the Surface Mass Balance Estimates over East Antarctica

    NASA Astrophysics Data System (ADS)

    Das, I.; Scambos, T. A.; Koenig, L.; Creyts, T. T.; Bell, R. E.; van den Broeke, M. R.; Lenaerts, J.; Paden, J. D.

    2014-12-01

    Accurate quantification of surface snow-accumulation over Antarctica is important for mass balance estimates and climate studies based on ice core records. An improved estimate of surface mass balance must include the significant role near-surface wind plays in the sublimation and redistribution of snow across Antarctica. We have developed an empirical model based on airborne radar and lidar observations, and modeled surface mass balance and wind fields to produce a continent-wide prediction of wind-scour zones over Antarctica. These zones have zero to negative surface mass balance, are located over locally steep ice sheet areas (>0.002) and controlled by bedrock topography. The near-surface winds accelerate over these zones, eroding and sublimating the surface snow. This scouring results in numerous localized regions (≤ 200 km2) with reduced surface accumulation. Each year, tens of gigatons of snow on the Antarctic ice sheet are ablated by persistent near-surface katabatic winds over these wind-scour zones. Large uncertainties remain in the surface mass balance estimates over East Antarctica as climate models do not adequately represent the small-scale physical processes that lead to mass loss through sublimation or redistribution over the wind-scour zones. In this study, we integrate Operation IceBridge's snow radar over the Recovery Ice Stream with a series of ice core dielectric and depth-density profiles for improved surface mass balance estimates that reflect the mass loss over the wind-scour zones. Accurate surface mass balance estimates from snow radars require spatially variable depth-density profiles. Using an ensemble of firn cores, MODIS-derived surface snow grain size, modeled accumulation rates and surface temperatures from RACMO2, we assemble spatially variable depth-density profiles and use our mapping of snow density variations to estimate layer mass and net accumulation rates from snow radar layer data. Our study improves the quantification of

  3. Shugan-decoction relieves visceral hyperalgesia and reduces TRPV1 and SP colon expression

    PubMed Central

    Shang, Jing-Juan; Yuan, Jian-Ye; Xu, Hui; Tang, Rong-Zhu; Dong, Yue-Bin; Xie, Jian-Qun

    2013-01-01

    AIM: To evaluate the therapeutic effect of Shugan-decoction (SGD) on visceral hyperalgesia and colon gene expressions using a rat model. METHODS: Ninety-six adult male Wistar rats were randomized into six equal groups for assessment of SGD effects on psychological stress-induced changes using the classic water avoidance stress (WAS) test. Untreated model rats were exposed to chronic (1 h/d for 10 d consecutive) WAS conditions; experimental treatment model rats were administered with intragastric SGD at 1 h before WAS on consecutive days 4-10 (low-dose: 0.1 g/mL; mid-dose: 0.2 g/mL; high-dose: 0.4 g/mL); control treatment model rats were similarly administered with the irritable bowel syndrome drug, dicetel (0.0042 g/mL); untreated normal control rats received no drug and were not subjected to the WAS test. At the end of the 10-d WAS testing period, a semi-quantitative measurement of visceral sensitivity was made by assessing the abdominal withdrawal reflex (AWR) to colorectal balloon-induced distension (at 5 mmHg increments) to determine the pain pressure threshold (PPT, evidenced by pain behavior). Subsequently, the animals were sacrificed and colonic tissues collected for assessment of changes in expressions of proteins related to visceral hypersensitivity (transient receptor potential vanilloid 1, TRPV1) and sustained visceral hyperalgesia (substance P, SP) by immunohistochemistry and real-time polymerase chain reaction. Inter-group differences were assessed by paired t test or repeated measures analysis of variance. RESULTS: The WAS test successfully induced visceral hypersensitivity, as evidenced by a significantly reduced AWR pressure in the untreated model group as compared to the untreated normal control group (190.4 ± 3.48 mmHg vs 224.0 ± 4.99 mmHg, P < 0.001). SGD treatments at mid-dose and high-dose and the dicetel treatment significantly increased the WAS-reduced PPT (212.5 ± 2.54, 216.5 ± 3.50 and 217.7 ± 2.83 mmHg respectively, all P < 0

  4. Investigation of water washes suitable for very small meat plants to reduce pathogens on beef surfaces.

    PubMed

    Yoder, Sally Flowers; Henning, William R; Mills, Edward W; Doores, Stephanie; Ostiguy, Nancy; Cutter, Catherine N

    2010-05-01

    Water washing with a handheld hose was performed on beef surfaces to ascertain the most effective combination of methods needed to remove potentially harmful microorganisms. For these experiments, beef brisket surfaces were experimentally inoculated with a fecal slurry containing Escherichia coli O157:H7, Salmonella Typhimurium, Campylobacter coli, and Campylobacter jejuni. In a pilot study, surfaces were washed with cold water (15 degrees C) at various water pressures, spray distances, application times, and drip times, and remaining bacterial populations were determined following the enumeration and isolation of pathogens and naturally occurring hygiene indicators (mesophilic aerobic bacteria, coliforms, and E. coli). The most efficacious combinations of these washing conditions were applied subsequently to artificially contaminated beef brisket surfaces in conjunction with hot (77 degrees C), warm (54 degrees C), and additional cold (15 degrees C) water washes. In the cold water washing pilot study, combinations of physical washing conditions significantly reduced all bacterial populations (P < 0.05). Further studies clearly indicated the superior bactericidal effectiveness of hot water washing; E. coli O157:H7 and Salmonella Typhimurium were reduced by 3.8 and 4.1 log CFU/cm(2), respectively. Overall, higher water temperature, longer application times, and shorter spray distances more effectively removed pathogens from inoculated beef surfaces. These findings will be used to formulate water washing recommendations for very small meat processing establishments. PMID:20501042

  5. Allelic imbalance modulates surface expression of the tolerance-inducing HLA-G molecule on primary trophoblast cells.

    PubMed

    Djurisic, S; Teiblum, S; Tolstrup, C K; Christiansen, O B; Hviid, T V F

    2015-03-01

    The HLA-G molecule is expressed on trophoblast cells at the feto-maternal interface, where it interacts with local immune cells, and upholds tolerance against the semi-allogeneic fetus. Aberrant HLA-G expression in the placenta and reduced soluble HLA-G levels are observed in pregnancy complications, partly explained by HLA-G polymorphisms which are associated with differences in the alternative splicing pattern and of the stability of HLA-G mRNA. Of special importance is a 14 bp insertion/deletion polymorphism located in the 3'-untranslated region of the HLA-G gene. In the current study, we present novel evidence for allelic imbalance of the 14 bp insertion/deletion polymorphism, using a very accurate and sensitive Digital droplet PCR technique. Allelic imbalance in heterozygous samples was observed as differential expression levels of 14 bp insertion/deletion allele-specific mRNA transcripts, which was further associated with low levels of HLA-G surface expression on primary trophoblast cells. Full gene sequencing of HLA-G allowed us to study correlations between HLA-G extended haplotypes and single-nucleotide polymorphisms and HLA-G surface expression. We found that a 1:1 expression (allelic balance) of the 14 bp insertion/deletion mRNA alleles was associated with high surface expression of HLA-G and with a specific HLA-G extended haplotype. The 14 bp del/del genotype was associated with a significantly lower abundance of the G1 mRNA isoform, and a higher abundance of the G3 mRNA isoform. Overall, the present study provides original evidence for allelic imbalance of the 14 bp insertion/deletion polymorphism, which influences HLA-G surface expression on primary trophoblast cells, considered to be important in the pathogenesis of pre-eclampsia and other pregnancy complications. PMID:25425608

  6. Stability analysis of surface tension effects on a double-diffusive layer. [in reduced gravity conditions

    NASA Technical Reports Server (NTRS)

    Chen, C. F.; Su, T. F.

    1992-01-01

    The linear stability characteristics of a fluid layer with simultaneous temperature and concentration gradients in a reduced gravity field are examined. The surface tension of the fluid is assumed to be a linear function of temperature and concentration. It is concluded that a small amount of gravity may damp out oscillatory instability or may alter its dynamics so that instability appears as steady convection. The onset of salt-finger instability may be in the overstable mode due to the surface tension method. The Lewis and Prandtl numbers of the material have a strong influence on the stability boundaries and onset characteristics of the system.

  7. Enhanced photothermal effect of surface oxidized silicon nanocrystals anchored to reduced graphene oxide nanosheets

    NASA Astrophysics Data System (ADS)

    Afshani, Parichehr; Moussa, Sherif; Atkinson, Garrett; Kisurin, Vitaly Y.; Samy El-Shall, M.

    2016-04-01

    We demonstrate the coupling of the photothermal effects of silicon nanocrystals and graphene oxide (GO) dispersed in water. Using laser irradiation (532 nm or 355 nm) of suspended Si nanocrystals in an aqueous solution of GO, the synthesis of surface oxidized Si-reduced GO nanocomposites (SiOx/Si-RGO) is reported. The laser reduction of GO is accompanied by surface oxidation of the Si nanocrystals resulting in the formation of the SiOx/Si-RGO nanocomposites. The SiOx/Si-RGO nanocomposites are proposed as promising materials for photothermal therapy and for the efficient conversion of solar energy into usable heat for a variety of thermal and thermomechanical applications.

  8. Inductive pulsed phase thermography for reducing or enlarging the effect of surface emissivity variation

    NASA Astrophysics Data System (ADS)

    Yang, Ruizhen; He, Yunze; Gao, Bin; Tian, Gui Yun

    2014-11-01

    Emissivity variation introduces illusory temperature inhomogeneity and results in false alarms in infrared thermography, thus, it is important to separate the influence of surface emissivity variation. This letter experimentally demonstrates the advantages of phase information to reduce or enlarge the effect of surface emissivity variation with inductive pulsed phase thermography, where inductive excitation is emissivity-independent and avoids the effect of emissivity variation in heating process. The directly heated area and the indirectly heated area are divided in the phasegrams. The emissivity variation is removed or enlarged perfectly at the specific frequency and defect detectability is improved remarkably.

  9. A method for reducing the level of spurious signals in surface acoustic wave filters

    NASA Astrophysics Data System (ADS)

    Borodii, Iu. N.; Grankin, I. M.; Zapunnyi, A. P.; Kolomeiko, A. V.

    1986-03-01

    A method for reducing spurious signals in surface acoustic wave (SAW) filters is proposed whereby both bulk and reflected wave signals are attenuated by electrodes of special configuration providing synphase addition of the useful signal and nonsynphase addition of spurious signal components. The electrodes of the input and output converters are made with a common focus point and equal angular apertures. The shape of the electrodes of the focusing converters on anisotropic crystal surfaces is determined by the corresponding SAW group velocity curve. An implementation of the method proposed here is examined together with some test results.

  10. Plasticity of sarcolemmal KATP channel surface expression: relevance during ischemia and ischemic preconditioning.

    PubMed

    Yang, Hua-Qian; Foster, Monique N; Jana, Kundan; Ho, Joanne; Rindler, Michael J; Coetzee, William A

    2016-06-01

    Myocardial ischemia remains the primary cause of morbidity and mortality in the United States. Ischemic preconditioning (IPC) is a powerful form of endogenous protection against myocardial infarction. We studied alterations in KATP channels surface density as a potential mechanism of the protection of IPC. Using cardiac-specific knockout of Kir6.2 subunits, we demonstrated an essential role for sarcolemmal KATP channels in the infarct-limiting effect of IPC in the mouse heart. With biochemical membrane fractionation, we demonstrated that sarcolemmal KATP channel subunits are distributed both to the sarcolemma and intracellular endosomal compartments. Global ischemia causes a loss of sarcolemmal KATP channel subunit distribution and internalization to endosomal compartments. Ischemia-induced internalization of KATP channels was prevented by CaMKII inhibition. KATP channel subcellular redistribution was also observed with immunohistochemistry. Ischemic preconditioning before the index ischemia reduced not only the infarct size but also prevented KATP channel internalization. Furthermore, not only did adenosine mimic IPC by preventing infarct size, but it also prevented ischemia-induced KATP channel internalization via a PKC-mediated pathway. We show that preventing endocytosis with dynasore reduced both KATP channel internalization and strongly mitigated infarct development. Our data demonstrate that plasticity of KATP channel surface expression must be considered as a potentially important mechanism of the protective effects of IPC and adenosine. PMID:27037371

  11. Surface-layer protein from Caulobacter crescentus: expression, purification and X-ray crystallographic analysis.

    PubMed

    Jones, Michael D; Chan, Anson C K; Nomellini, John F; Murphy, Michael E P; Smit, John

    2016-09-01

    Protein surface layers are self-assembling, paracrystalline lattices on the surface of many prokaryotes. Surface-layer proteins have not benefited from widespread structural analysis owing to their resistance to crystallization. Here, the successful expression of a truncated version of RsaA, the surface-layer protein from Caulobacter crescentus, from a Caulobacter protein-expression system is reported. The purification, crystallization and initial X-ray diffraction analysis of the truncated RsaA, the largest surface-layer protein studied to date and the first from a Gram-negative bacterium, are also reported. PMID:27599857

  12. Nifurtimox reduces N-Myc expression and aerobic glycolysis in neuroblastoma

    PubMed Central

    Cabanillas Stanchi, Karin Melanie; Bruchelt, Gernot; Handgretinger, Rupert; Holzer, Ursula

    2015-01-01

    Neuroblastoma is one of the most common solid tumors in childhood and usually accompanied with poor prognosis and rapid tumor progression when diagnosed with amplification of the proto-oncogene N-Myc. The amplification of N-Myc has major influence on the maintenance of aerobic glycolysis, also known as the Warburg effect. This specific switch in the conversion of pyruvate to lactate instead of the conversion of pyruvate to acetyl-coenzyme A even in the presence of oxygen has important benefits for the tumor, e.g. increased production of enzymes and enzyme substrates that are involved in tumor progression, angiogenesis and inhibition of apoptosis. The antiprotozoal drug nifurtimox, which is generally used for the treatment of infections with the parasitic protozoan Trypanosoma cruzi, has been reported to have cytotoxic properties in the therapy of neuroblastoma. However, its action of mechanism has not been described in detail yet. The presented in vitro study on the neuroblastoma cell lines LA-N-1, IMR-32, LS and SK-N-SH shows an increased production of oxidative stress, a reduced lactate dehydrogenase enzyme activity and reduced lactate production after nifurtimox treatment. Furthermore, nifurtimox leads to reduced mRNA and protein levels of the proto-oncogene protein N-Myc. Thus, the current work gives new insights into the effect of nifurtimox on tumor metabolism revealing a shifted glucose metabolism from production of lactate to oxidative phosphorylation and a reduced expression of the major molecular prognostic factor in neuroblastoma N-Myc, presenting nifurtimox as a possible adjuvant therapeutic agent against (high risk) neuroblastoma. PMID:26177922

  13. Ordered Boolean List (OBL): reducing the footprint for evaluating Boolean expressions.

    PubMed

    Rossignac, Jaroslaw Jarek

    2011-09-01

    An Expanded Boolean Expression (EBE) does not contain any XOR or EQUAL operators. The occurrence of each variable is a different literal. We provide a linear time algorithm that converts an EBE of n literals into a logically equivalent Ordered Boolean List (OBL) and show how to use the OBL to evaluate the EBE in n steps and O(log log n) space, if the values of the literals are each read once in the order prescribed by the OBL. (An evaluation workspace of 5 bits suffices for all EBEs of up to six billion literals.) The primary application is the SIMD architecture, where the same EBE is evaluated in parallel for different input vectors when rendering solid models on the GPU directly from their Constructive Solid Geometry (CSG) representation. We compare OBL to the Reduced Ordered Binary Decision Diagram (ROBDD) and suggest possible applications of OBL to logic verification and to circuit design. PMID:21737862

  14. Reducing the drying shrinkage of cement paste by admixture surface treatments

    SciTech Connect

    Xu, Y.; Chung, D.D.L.

    2000-02-01

    The drying shrinkage of concrete during curing is a source of residual stress and cracks. The problem is particularly severe for a large structure, such as a large concrete floor. Surface treatment of carbon fibers and/or silica fume by silane prior to using these admixtures in cement paste increases the effectiveness of these admixtures for reducing the drying shrinkage. Silane treatment of fibers is more effective than dichromate treatment or ozone treatment.

  15. Surface modifications of photoanodes in dye sensitized solar cells: enhanced light harvesting and reduced recombination

    NASA Astrophysics Data System (ADS)

    Saxena, Vibha; Aswal, D. K.

    2015-06-01

    In a quest to harvest solar power, dye-sensitized solar cells (DSSCs) have potential for low-cost eco-friendly photovoltaic devices. The major processes which govern the efficiency of a DSSC are photoelectron generation, injection of photo-generated electrons to the conduction band (CB) of the mesoporous nanocrystalline semiconductor (nc-SC); transport of CB electrons through nc-SC and subsequent collection of CB electrons at the counter electrode (CE) through the external circuit; and dye regeneration by redox couple or hole transport layer (HTL). Most of these processes occur at various interfaces of the photoanode. In addition, recombination losses of photo-generated electrons with either dye or redox molecules take place at the interfaces. Therefore, one of the key requirements for high efficiency is to improve light harvesting of the photoanode and to reduce the recombination losses at various interfaces. In this direction, surface modification of the photoanode is the simplest method among the various other approaches available in the literature. In this review, we present a comprehensive discussion on surface modification of the photoanode, which has been adopted in the literature for not only enhancing light harvesting but also reducing recombination. Various approaches towards surface modification of the photoanode discussed are (i) fluorine-doped tin oxide (FTO)/nc-SC interface modified via a compact layer of semiconductor material which blocks exposed sites of FTO to electrolyte (or HTL), (ii) nc-SC/dye interface modification either through acid treatment resulting in enhanced dye loading due to a positively charged surface or by depositing insulating/semiconducting blocking layer on the nc-SC surface, which acts as a tunneling barrier for recombination, (iii) nc-SC/dye interface modified by employing co-adsorbents which helps in reducing the dye aggregation and thereby recombination, and (iv) dye/electrolyte (or dye/HTL) interface modification using

  16. Hyperglycemia reduces functional expression of astrocytic Kir4.1 channels and glial glutamate uptake.

    PubMed

    Rivera-Aponte, D E; Méndez-González, M P; Rivera-Pagán, A F; Kucheryavykh, Y V; Kucheryavykh, L Y; Skatchkov, S N; Eaton, M J

    2015-12-01

    Diabetics are at risk for a number of serious health complications including an increased incidence of epilepsy and poorer recovery after ischemic stroke. Astrocytes play a critical role in protecting neurons by maintaining extracellular homeostasis and preventing neurotoxicity through glutamate uptake and potassium buffering. These functions are aided by the presence of potassium channels, such as Kir4.1 inwardly rectifying potassium channels, in the membranes of astrocytic glial cells. The purpose of the present study was to determine if hyperglycemia alters Kir4.1 potassium channel expression and homeostatic functions of astrocytes. We used q-PCR, Western blot, patch-clamp electrophysiology studying voltage and potassium step responses and a colorimetric glutamate clearance assay to assess Kir4.1 channel levels and homeostatic functions of rat astrocytes grown in normal and high glucose conditions. We found that astrocytes grown in high glucose (25 mM) had an approximately 50% reduction in Kir4.1 mRNA and protein expression as compared with those grown in normal glucose (5mM). These reductions occurred within 4-7 days of exposure to hyperglycemia, whereas reversal occurred between 7 and 14 days after return to normal glucose. The decrease in functional Kir channels in the astrocytic membrane was confirmed using barium to block Kir channels. In the presence of 100-μM barium, the currents recorded from astrocytes in response to voltage steps were reduced by 45%. Furthermore, inward currents induced by stepping extracellular [K(+)]o from 3 to 10mM (reflecting potassium uptake) were 50% reduced in astrocytes grown in high glucose. In addition, glutamate clearance by astrocytes grown in high glucose was significantly impaired. Taken together, our results suggest that down-regulation of astrocytic Kir4.1 channels by elevated glucose may contribute to the underlying pathophysiology of diabetes-induced CNS disorders and contribute to the poor prognosis after stroke

  17. Borrelia burgdorferi intercepts host hormonal signals to regulate expression of outer surface protein A

    PubMed Central

    Scheckelhoff, Mark R.; Telford, Sam R.; Wesley, Mary; Hu, Linden T.

    2007-01-01

    The Borrelia burgdorferi infectious cycle requires that the organism adapt to vast differences in environmental conditions found in its tick and mammalian hosts. Previous studies have shown that B. burgdorferi accomplishes this accomodation in part by regulating expression of its surface proteins. Outer surface protein A (OspA) is a borrelial protein important in colonization of the tick midgut. OspA is up-regulated when the organism is in its tick host and down-regulated when it is in a mammalian host. However, little is known about how it is up-regulated again in a mammalian host in preparation for entry into a feeding tick. Here, we report that the host neuroendocrine stress hormones, epinephrine and norepinephrine, are specifically bound by B. burgdorferi and result in increased expression of OspA. This recognition is specific and blocked by competitive inhibitors of human adrenergic receptors. To determine whether recognition of catecholamines, which are likely to be present at the site of a tick bite, may play a role in preparing the organism for reentry into a tick from a mammalian host, we administered a β-adrenergic blocker, propranolol, to infected mice. Propranolol significantly reduced uptake of B. burgdorferi by feeding ticks and decreased expression of OspA in B. burgdorferi recovered from ticks that fed on propranolol-treated mice. Our studies suggest that B. burgdorferi may co-opt host neuroendocrine signals to inform the organism of local changes that predict the presence of its next host and allow it to prepare for transition to a new environment. PMID:17438273

  18. Kefir reduces insulin resistance and inflammatory cytokine expression in an animal model of metabolic syndrome.

    PubMed

    Rosa, Damiana D; Grześkowiak, Łukasz M; Ferreira, Célia L L F; Fonseca, Ana Carolina M; Reis, Sandra A; Dias, Mariana M; Siqueira, Nathane P; Silva, Leticia L; Neves, Clóvis A; Oliveira, Leandro L; Machado, Alessandra B F; Peluzio, Maria do Carmo G

    2016-08-10

    There is growing evidence that kefir can be a promising tool in decreasing the risk of many diseases, including metabolic syndrome (MetS). The aim of the present study was to evaluate the effect of kefir supplementation in the diet of Spontaneously Hypertensive Rats (SHR) in which MetS was induced with monosodium glutamate (MSG), and to determine its effect on metabolic parameters, inflammatory and oxidation marker expression and glycemic index control. Thirty animals were used in this experiment. For the induction of MetS, twenty two-day-old male SHR received five consecutive intradermal injections of MSG. For the Negative Control, ten newborn male SHR received intradermal injections of saline solution (0.9% saline solution). After weaning, animals received standard diet and water ad libitum until reaching 3 months old, for the development of MetS. They were then divided into three groups (n = 10): negative control (NC, 1 mL saline solution per day), positive control (PC, 1 mL saline solution per day) and the Kefir group (1 mL kefir per day). Feeding was carried out by gavage for 10 weeks and the animals received standard food and water ad libitum. Obesity, insulin resistance, pro- and anti-inflammatory markers, and the histology of pancreatic and adipose tissues were among the main variables evaluated. Compared to the PC group, kefir supplementation reduced plasma triglycerides, liver lipids, liver triglycerides, insulin resistance, fasting glucose, fasting insulin, thoracic circumference, abdominal circumference, products of lipid oxidation, pro-inflammatory cytokine expression (IL-1β) and increased anti-inflammatory cytokine expression (IL-10). The present findings indicate that kefir has the potential to benefit the management of MetS. PMID:27384318

  19. KCTD11 tumor suppressor gene expression is reduced in prostate adenocarcinoma.

    PubMed

    Zazzeroni, Francesca; Nicosia, Daniela; Tessitore, Alessandra; Gallo, Rita; Verzella, Daniela; Fischietti, Mariafausta; Vecchiotti, Davide; Ventura, Luca; Capece, Daria; Gulino, Alberto; Alesse, Edoardo

    2014-01-01

    Prostate cancer is the most common noncutaneous cancer among men in the United States. A genetic contribution to prostate cancer risk has been documented, but knowledge of the molecular mechanisms involved in prostate cancer initiation is still not well understood. Loss of heterozygosity (LOH) of chromosomal regions is crucial in tumor progression. In human prostate cancer, several chromosomal regions demonstrating a high frequency of LOH have been previously identified. KCTD11 (REN) is a tumor suppressor gene mapping on human chromosome 17p13.2, whose expression is frequently lost in human medulloblastoma and in several other cancer types. KCTD11 acts as a negative regulator of the Hedgehog (Hh) signaling. Here, we demonstrated that KCTD11 LOH is a common genetic lesion in human prostate adenocarcinoma. Indeed, nuclear KCTD11 protein expression is strongly reduced in primary prostate cancer, and this event correlated with overexpression of proteins acting into the Hedgehog pathway. Low levels of KCTD11 mRNA have been also observed in prostatic cancer cells, and ectopic overexpression of KCTD11 led to growth arrest. Our study demonstrates and supports that KCTD11, as well as negatively regulated downstream effectors belonging to Hh signaling, plays a role in prostate cancer pathogenesis. This could be suitable to characterize new diagnostic and therapeutic markers. PMID:25045667

  20. KCTD11 Tumor Suppressor Gene Expression Is Reduced in Prostate Adenocarcinoma

    PubMed Central

    Zazzeroni, Francesca; Nicosia, Daniela; Tessitore, Alessandra; Gallo, Rita; Verzella, Daniela; Fischietti, Mariafausta; Vecchiotti, Davide; Ventura, Luca; Capece, Daria; Gulino, Alberto; Alesse, Edoardo

    2014-01-01

    Prostate cancer is the most common noncutaneous cancer among men in the United States. A genetic contribution to prostate cancer risk has been documented, but knowledge of the molecular mechanisms involved in prostate cancer initiation is still not well understood. Loss of heterozygosity (LOH) of chromosomal regions is crucial in tumor progression. In human prostate cancer, several chromosomal regions demonstrating a high frequency of LOH have been previously identified. KCTD11 (REN) is a tumor suppressor gene mapping on human chromosome 17p13.2, whose expression is frequently lost in human medulloblastoma and in several other cancer types. KCTD11 acts as a negative regulator of the Hedgehog (Hh) signaling. Here, we demonstrated that KCTD11 LOH is a common genetic lesion in human prostate adenocarcinoma. Indeed, nuclear KCTD11 protein expression is strongly reduced in primary prostate cancer, and this event correlated with overexpression of proteins acting into the Hedgehog pathway. Low levels of KCTD11 mRNA have been also observed in prostatic cancer cells, and ectopic overexpression of KCTD11 led to growth arrest. Our study demonstrates and supports that KCTD11, as well as negatively regulated downstream effectors belonging to Hh signaling, plays a role in prostate cancer pathogenesis. This could be suitable to characterize new diagnostic and therapeutic markers. PMID:25045667

  1. Disrupting Protein Expression with Peptide Nucleic Acids Reduces Infection by Obligate Intracellular Rickettsia

    PubMed Central

    Pelc, Rebecca S.; McClure, Jennifer C.; Kaur, Simran J.; Sears, Khandra T.; Rahman, M. Sayeedur; Ceraul, Shane M.

    2015-01-01

    Peptide Nucleic Acids (PNAs) are single-stranded synthetic nucleic acids with a pseudopeptide backbone in lieu of the phosphodiester linked sugar and phosphate found in traditional oligos. PNA designed complementary to the bacterial Shine-Dalgarno or start codon regions of mRNA disrupts translation resulting in the transient reduction in protein expression. This study examines the use of PNA technology to interrupt protein expression in obligate intracellular Rickettsia sp. Their historically intractable genetic system limits characterization of protein function. We designed PNA targeting mRNA for rOmpB from Rickettsia typhi and rickA from Rickettsia montanensis, ubiquitous factors important for infection. Using an in vitro translation system and competitive binding assays, we determined that our PNAs bind target regions. Electroporation of R. typhi and R. montanensis with PNA specific to rOmpB and rickA, respectively, reduced the bacteria’s ability to infect host cells. These studies open the possibility of using PNA to suppress protein synthesis in obligate intracellular bacteria. PMID:25781160

  2. Spectroscopic study of surface enhanced Raman scattering of caffeine on borohydride-reduced silver colloids

    NASA Astrophysics Data System (ADS)

    Chen, Xiaomin; Gu, Huaimin; Shen, Gaoshan; Dong, Xiao; Kang, Jian

    2010-06-01

    The surface enhanced Raman scattering (SERS) of caffeine on borohydride-reduced silver colloids system under different aqueous solution environment has been studied in this paper. The relative intensity of SERS of caffeine significantly varies with different concentrations of sodium chloride and silver particles. However, at too high or too low concentration of sodium chloride and silver particle, the enhancement of SERS spectra is not evident. The SERS spectra of caffeine suggest that the contribution of the charge transfer mechanism to SERS may be dominant. The chloride ions can significantly enhance the efficiency of SERS, while the enhancement is selective, as the efficiency in charge transfer enhancement is higher than in electromagnetic enhancement. Therefore, it can be concluded that the active site of chloride ion locates on the bond between the caffeine and the silver surface. In addition, the SERS spectra of caffeine on borohydride-reduced and citrate-reduced silver colloids are different, which may be due to different states caffeine adsorbed on silver surface under different silver colloids.

  3. Ab initio modeling of the bonding of benzotriazole corrosion inhibitor to reduced and oxidized copper surfaces.

    PubMed

    Kokalj, Anton

    2015-01-01

    The bonding of benzotriazole-an outstanding corrosion inhibitor for copper-on reduced and oxidized copper surfaces is discussed on the basis of density functional theory (DFT) calculations. Calculations reveal that benzotriazole is able to bond with oxide-free and oxidized copper surfaces and on both of them it bonds significantly stronger to coordinatively unsaturated Cu sites. This suggests that benzotriazole is able to passivate the reactive under-coordinated surface sites that are plausible microscopic sites for corrosion attack. Benzotriazole can adsorb in a variety of different forms, yet it forms a strong molecule-surface bond only in deprotonated form. The bonding is even stronger when the deprotonated form is incorporated into organometallic adcomplexes. This is consistent with existing experimental evidence that benzotriazole inhibits corrosion by forming protective organometallic complexes. It is further shown that adsorption of benzotriazole considerably reduces the metal work function, which is a consequence of a large permanent molecular dipole and a properly oriented adsorption structure. It is argued that such a pronounced effect on the work function might be relevant for corrosion inhibition, because it should diminish the anodic corrosion reaction, which is consistent with existing experimental evidence that benzotriazole, although a mixed type inhibitor, predominantly affects the anodic reaction. PMID:25955130

  4. Immobilized Silver Nanoparticles on Chitosan with Special Surface State-Enhanced Antimicrobial Efficacy and Reduced Cytotoxicity.

    PubMed

    He, Miao; Lu, Liying; Zhang, Jinchi; Li, Danzhen

    2015-09-01

    Immobilized chitosan-Ag nanoparticles (CTS-Ag NPs) with special surface state have been synthesized successfully through immobilizing Ag NPs on the amino-enriched surface of CTS by reducing Ag (I) in situ. The antimicrobial efficiency and potency of CTS-Ag NPs against Escherichia coli and Staphylococcus aureus were studied. Our results reveal that surface-immobilized CTS-Ag NPs show better antimicrobial efficacy than several other reported monodisperse colloidal Ag NPs, because the unique surface state of our CTS-Ag NPs leads to both "contact killing" and "ion mediated killing" functions. Due to the synergetic effect of CTS and Ag NPs, the immobilized CTS-Ag NPs present a broader antimicrobial spectrum and a more effective antifungal activity against Monilia albican. In addition, CTS as an environment friendly dispersant can help to reduce the cytotoxicity of Ag NPs on higher organisms. The immobilized CTS-Ag NPs are stable and can maintain good disinfection potential after 6 months' shelf-time. PMID:26716197

  5. Reducing bacteria and macrophage density on nanophase hydroxyapatite coated onto titanium surfaces without releasing pharmaceutical agents

    NASA Astrophysics Data System (ADS)

    Bhardwaj, Garima; Yazici, Hilal; Webster, Thomas J.

    2015-04-01

    Reducing bacterial density on titanium implant surfaces has been a major concern because of the increasing number of nosocomial infections. Controlling the inflammatory response post implantation has also been an important issue for medical devices due to the detrimental effects of chronic inflammation on device performance. It has recently been demonstrated that manipulating medical device surface properties including chemistry, roughness and wettability can control both infection and inflammation. Here, we synthesized nanophase (that is, materials with one dimension in the nanoscale) hydroxyapatite coatings on titanium to reduce bacterial adhesion and inflammatory responses (as measured by macrophage functions) and compared such results to bare titanium and plasma sprayed hydroxyapatite titanium coated surfaces used clinically today. This approach is a pharmaceutical-free approach to inhibit infection and inflammation due to the detrimental side effects of any drug released in the body. Here, nanophase hydroxyapatite was synthesized in sizes ranging from 110-170 nm and was subsequently coated onto titanium samples using electrophoretic deposition. Results indicated that smaller nanoscale hydroxyapatite features on titanium surfaces alone decreased bacterial attachment in the presence of gram negative (P. aeruginosa), gram positive (S. aureus) and ampicillin resistant gram-negative (E. coli) bacteria as well as were able to control inflammatory responses; properties which should lead to their further investigation for improved medical applications.

  6. Standing on a declining surface reduces transient prolonged standing induced low back pain development.

    PubMed

    Gallagher, Kaitlin M; Callaghan, Jack P

    2016-09-01

    While alternating standing position on a sloped surface has proven successful at reducing low back pain during standing, the purpose of this study was to evaluate standing solely on a declining surface to isolate the influence of the postural change. Seventeen participants performed two 75-min prolonged standing occupational simulations- level ground and declining surface. Fifty-three percent of participants (9/17) were categorized as pain developers during the level ground standing condition. For these same pain developers, their average maximum pain scores were 58% lower during sloped standing. All participants showed greater hip flexion, trunk-to-thigh angle flexion, and posterior translation of the trunk center of gravity when standing on the sloped surface. These postural changes could cause the muscles crossing the hip posteriorly to increase passive stiffness and assist with stabilizing the pelvis. This study stresses the importance of hip kinematics, not just lumbar spine posture, in reducing prolonged standing induced low back pain. PMID:27184314

  7. Surface expression of the hRSV nucleoprotein impairs immunological synapse formation with T cells

    PubMed Central

    Céspedes, Pablo F.; Bueno, Susan M.; Ramírez, Bruno A.; Gomez, Roberto S.; Riquelme, Sebastián A.; Palavecino, Christian E.; Mackern-Oberti, Juan Pablo; Mora, Jorge E.; Depoil, David; Sacristán, Catarina; Cammer, Michael; Creneguy, Alison; Nguyen, Tuan H.; Riedel, Claudia A.; Dustin, Michael L.; Kalergis, Alexis M.

    2014-01-01

    Human respiratory syncytial virus (hRSV) is the leading cause of bronchiolitis and pneumonia in young children worldwide. The recurrent hRSV outbreaks and reinfections are the cause of a significant public health burden and associate with an inefficient antiviral immunity, even after disease resolution. Although several mouse- and human cell-based studies have shown that hRSV infection prevents naïve T-cell activation by antigen-presenting cells, the mechanism underlying such inhibition remains unknown. Here, we show that the hRSV nucleoprotein (N) could be at least partially responsible for inhibiting T-cell activation during infection by this virus. Early after infection, the N protein was expressed on the surface of epithelial and dendritic cells, after interacting with trans-Golgi and lysosomal compartments. Further, experiments on supported lipid bilayers loaded with peptide-MHC (pMHC) complexes showed that surface-anchored N protein prevented immunological synapse assembly by naive CD4+ T cells and, to a lesser extent, by antigen-experienced T-cell blasts. Synapse assembly inhibition was in part due to reduced T-cell receptor (TCR) signaling and pMHC clustering at the T-cell−bilayer interface, suggesting that N protein interferes with pMHC−TCR interactions. Moreover, N protein colocalized with the TCR independently of pMHC, consistent with a possible interaction with TCR complex components. Based on these data, we conclude that hRSV N protein expression at the surface of infected cells inhibits T-cell activation. Our study defines this protein as a major virulence factor that contributes to impairing acquired immunity and enhances susceptibility to reinfection by hRSV. PMID:25056968

  8. Reduced FOXO1 Expression Accelerates Skin Wound Healing and Attenuates Scarring

    PubMed Central

    Mori, Ryoichi; Tanaka, Katsuya; de Kerckhove, Maiko; Okamoto, Momoko; Kashiyama, Kazuya; Tanaka, Katsumi; Kim, Sangeun; Kawata, Takuya; Komatsu, Toshimitsu; Park, Seongjoon; Ikematsu, Kazuya; Hirano, Akiyoshi; Martin, Paul; Shimokawa, Isao

    2015-01-01

    The forkhead box O (FOXO) family has been extensively investigated in aging and metabolism, but its role in tissue-repair processes remains largely unknown. Herein, we clarify the molecular aspect of the FOXO family in skin wound healing. We demonstrated that Foxo1 and Foxo3a were both up-regulated during murine skin wound healing. Partial knockout of Foxo1 in Foxo1+/− mice throughout the body led to accelerated skin wound healing with enhanced keratinocyte migration, reduced granulation tissue formation, and decreased collagen density, accompanied by an attenuated inflammatory response, but we observed no wound phenotype in Foxo3a−/− mice. Fibroblast growth factor 2, adiponectin, and notch1 genes were significantly increased at wound sites in Foxo1+/− mice, along with markedly altered extracellular signal–regulated kinase 1/2 and AKT phosphorylation. Similarly, transient knockdown of Foxo1 at the wound site by local delivery of antisense oligodeoxynucleotides enhanced skin wound healing. The link between FOXO1 and scarring extends to patients, in particular keloid scars, where we see FOXO1 expression markedly increased in fibroblasts and inflammatory cells within the otherwise normal dermis. This occurs in the immediate vicinity of the keloid by comparison to the center of the mature keloid, indicating that FOXO1 is associated with the overgrowth of this fibrotic response into adjacent normal skin. Overall, our data indicate that molecular targeting of FOXO1 may improve the quality of healing and reduce pathological scarring. PMID:25010393

  9. Inhibition of hypothalamic Foxo1 expression reduced food intake in diet-induced obesity rats

    PubMed Central

    Ropelle, Eduardo R; Pauli, José R; Prada, Patrícia; Cintra, Dennys E; Rocha, Guilherme Z; Moraes, Juliana C; Frederico, Marisa J S; da Luz, Gabrielle; Pinho, Ricardo A; Carvalheira, José B C; Velloso, Licio A; Saad, Mario A; De Souza, Cláudio T

    2009-01-01

    Insulin signalling in the hypothalamus plays a role in maintaining body weight. The forkhead transcription factor Foxo1 is an important mediator of insulin signalling in the hypothalamus. Foxo1 stimulates the transcription of the orexigenic neuropeptide Y and Agouti-related protein through the phosphatidylinositol-3-kinase/Akt signalling pathway, but the role of hypothalamic Foxo1 in insulin resistance and obesity remains unclear. Here, we identify that a high-fat diet impaired insulin-induced hypothalamic Foxo1 phosphorylation and degradation, increasing the nuclear Foxo1 activity and hyperphagic response in rats. Thus, we investigated the effects of the intracerebroventricular (i.c.v.) microinfusion of Foxo1-antisense oligonucleotide (Foxo1-ASO) and evaluated the food consumption and weight gain in normal and diet-induced obese (DIO) rats. Three days of Foxo1-ASO microinfusion reduced the hypothalamic Foxo1 expression by about 85%. i.c.v. infusion of Foxo1-ASO reduced the cumulative food intake (21%), body weight change (28%), epididymal fat pad weight (22%) and fasting serum insulin levels (19%) and increased the insulin sensitivity (34%) in DIO but not in control animals. Collectively, these data showed that the Foxo1-ASO treatment blocked the orexigenic effects of Foxo1 and prevented the hyperphagic response in obese rats. Thus, pharmacological manipulation of Foxo1 may be used to prevent or treat obesity. PMID:19332486

  10. Involvement of aberrant DNA methylation on reduced expression of lysophosphatidic acid receptor-1 gene in rat tumor cell lines

    SciTech Connect

    Tsujiuchi, Toshifumi . E-mail: ttujiuch@life.kindai.ac.jp; Shimizu, Kyoko; Onishi, Mariko; Sugata, Eriko; Fujii, Hiromasa; Mori, Toshio; Honoki, Kanya; Fukushima, Nobuyuki

    2006-10-27

    Lysophosphatidic acid (LPA) is a bioactive phospholipid that stimulates cell proliferation, migration, and protects cells from apoptosis. It interacts with specific G protein-coupled transmembrane receptors. Recently, it has been reported that alterations of LPA receptor expression might be important in the malignant transformation of tumor cells. Therefore, to assess an involvement of DNA methylation in reduced expression of the LPA receptor-1 (lpa1) gene, we investigated the expression of the lpa1 gene and its DNA methylation patterns in rat tumor cell lines. Both rat brain-derived neuroblastoma B103 and liver-derived hepatoma RH7777 cells used in this study indicated no expression of lpa1. For the analysis of methylation status, bisulfite sequencing was performed with B103 and RH7777 cells, comparing with other lpa1 expressed cells and normal tissues of brain and liver. The lpa1 expressed cells and tissues were all unmethylated in this region of lpa1. In contrast, both B103 and RH7777 cells were highly methylated, correlating with reduced expression of the lpa1. Treatment with 5-aza 2'-deoxycytidine induced expression of lpa1 gene in B103 and RH7777 cells after 24 h. In RH7777 cells treated with 5-aza 2'-deoxycytidine, stress fiber formation was also observed in response to LPA in RH7777 cells, but not in untreated RH7777 cells. These results suggest that aberrant DNA methylation of the lpa1 gene may be involved in its reduced expression in rat tumor cells.

  11. MicroRNA-194 Modulates Glucose Metabolism and Its Skeletal Muscle Expression Is Reduced in Diabetes

    PubMed Central

    Latouche, Celine; Natoli, Alaina; Reddy-Luthmoodoo, Medini; Heywood, Sarah E.; Armitage, James A.; Kingwell, Bronwyn A.

    2016-01-01

    Background The regulation of microRNAs (miRNAs) at different stages of the progression of type 2 diabetes mellitus (T2DM) and their role in glucose homeostasis was investigated. Methods Microarrays were used to assess miRNA expression in skeletal muscle biopsies taken from healthy individuals and patients with pre-diabetes or T2DM, and insulin resistant offspring of rat dams fed a high fat diet during pregnancy. Results Twenty-three miRNAs were differentially expressed in patients with T2DM, and 7 in the insulin resistant rat offspring compared to their controls. Among these, only one miRNA was similarly regulated: miR-194 expression was significantly reduced by 25 to 50% in both the rat model and in human with pre-diabetes and established diabetes. Knockdown of miR-194 in L6 skeletal muscle cells induced an increase in basal and insulin-stimulated glucose uptake and glycogen synthesis. This occurred in conjunction with an increased glycolysis, indicated by elevated lactate production. Moreover, oxidative capacity was also increased as we found an enhanced glucose oxidation in presence of the mitochondrial uncoupler FCCP. When miR-194 was down-regulated in vitro, western blot analysis showed an increased phosphorylation of AKT and GSK3β in response to insulin, and an increase in expression of proteins controlling mitochondrial oxidative phosphorylation. Conclusions Type 2 diabetes mellitus is associated with regulation of several miRNAs in skeletal muscle. Interestingly, miR-194 was a unique miRNA that appeared regulated across different stages of the disease progression, from the early stages of insulin resistance to the development of T2DM. We have shown miR-194 is involved in multiple aspects of skeletal muscle glucose metabolism from uptake, through to glycolysis, glycogenesis and glucose oxidation, potentially via mechanisms involving AKT, GSK3 and oxidative phosphorylation. MiR-194 could be down-regulated in patients with early features of diabetes as an

  12. Expression of proinflammatory, proatherogenic genes is reduced by the Mediterranean diet in elderly people.

    PubMed

    Camargo, Antonio; Delgado-Lista, Javier; Garcia-Rios, Antonio; Cruz-Teno, Cristina; Yubero-Serrano, Elena M; Perez-Martinez, Pablo; Gutierrez-Mariscal, Francisco M; Lora-Aguilar, Pilar; Rodriguez-Cantalejo, Fernando; Fuentes-Jimenez, Francisco; Tinahones, Francisco Jose; Malagon, Maria M; Perez-Jimenez, Francisco; Lopez-Miranda, Jose

    2012-08-01

    Ageing is an important determinant of atherosclerosis development rate, mainly by the creation of a chronic low-grade inflammation. Diet, and particularly its fat content, modulates the inflammatory response in the fasting and postprandial states. Our aim was to study the effects of dietary fat on the expression of genes related to inflammation (NF-κB, monocyte chemoattractant protein 1 (MCP-1), TNF-α and IL-6) and plaque stability (matrix metalloproteinase 9, MMP-9) during the postprandial state of twenty healthy, elderly people who followed three diets for 3 weeks each: (1) Mediterranean diet (Med Diet) enriched in MUFA with virgin olive oil; (2) SFA-rich diet; and (3) low-fat, high-carbohydrate diet enriched in n-3 PUFA (CHO-PUFA diet) by a randomised crossover design. At the end of each period, after a 12-h fast, the subjects received a breakfast with a composition similar to the one when the dietary period ended. In the fasting state, the Med Diet consumption induced a lower gene expression of the p65 subunit of NF-κB compared with the SFA-rich diet (P = 0·019). The ingestion of the Med Diet induced a lower gene postprandial expression of p65 (P = 0·033), MCP-1 (P = 0·0229) and MMP-9 (P = 0·041) compared with the SFA-rich diet, and a lower gene postprandial expression of p65 (P = 0·027) and TNF-α (P = 0·047) compared with the CHO-PUFA diet. Direct plasma quantification mostly reproduced the findings. Our data suggest that consumption of a Med Diet reduces the postprandial inflammatory response in mononuclear cells compared with the SFA-rich and CHO-PUFA diets in elderly people. These findings may be partly responsible for the lower CVD risk found in populations with a high adherence to the Med Diet. PMID:22085595

  13. Reducing phosphorus loading of surface water using iron-coated sand.

    PubMed

    Groenenberg, Jan E; Chardon, Wim J; Koopmans, Gerwin F

    2013-01-01

    Phosphorus losses from agricultural soils is an important source of P in surface waters leading to surface water quality impairment. In addition to reducing P inputs, mitigation measures are needed to reduce P enrichment of surface waters. Because drainage of agricultural land by pipe drainage is an important pathway of P to surface waters, removing P from drainage water has a large potential to reduce P losses. In a field trial, we tested the performance of a pipe drain enveloped with Fe-coated sand, a side product of the drinking water industry with a high ability to bind P, to remove P from the drainage water. The results of this trial, encompassing more than one hydrological season, are very encouraging because the efficiency of this mitigation measure to remove P amounted to 94%. During the trial, the pipe drains were below the groundwater level for a prolonged time. Nevertheless, no reduction of Fe(III) in the Fe-coated sand occurred, which was most likely prevented by reduction of Mn oxides present in this material. The enveloped pipe drain was estimated to be able to lower the P concentration in the effluent to the desired water quality criterion for about 14 yr. Manganese oxides are expected to be depleted after 5 to 10 yr. The performance of the enveloped pipe drain, both in terms of its ability to remove P to a sufficiently low level and the stability of the Fe-coated sand under submerged conditions in the long term, needs prolonged experimental research. PMID:23673760

  14. Surface modification on microfluidic devices with 2-methacryloyloxyethyl phosphorylcholine polymers for reducing unfavorable protein adsorption.

    PubMed

    Sibarani, James; Takai, Madoka; Ishihara, Kazuhiko

    2007-01-15

    Surface modification of polymer materials for preparing microfluidic devices including poly(dimethyl siloxane) (PDMS) was investigated with phospholipids polymers such as poly(2-methacryloyloxylethyl phosphorylcholine(MPC)-co-n-butyl methacrylate) (PMB) and poly(MPC-co-2-ethylhexyl methacrylate-co-2-(N,N-dimethylamino)ethyl methacrylate) (PMED). The hydrophilicity of every surface on the polymer materials modified with these MPC polymers increased and the value of zeta-potential became close to zero. The protein adsorption on the polymer materials with and without the surface modification was evaluated using a protein mixture of human plasma fibrinogen and serum albumin. Amount of proteins adsorbed on these polymeric materials showed significant reduction by the surface modification with the MPC polymers compared to the uncoated surfaces ranging from 56 to 90%. Furthermore, we successfully prepared PDMS-based microchannel which was modified by simple coating with the PMB and PMED. The modified microchannel also revealed a significant reduction of adsorption of serum albumin. We conclude that the MPC polymers are useful for reducing unfavorable protein adsorption on microfluidic devices. PMID:17112710

  15. Morphology of gas cavities on patterned hydrophobic surfaces under reduced pressure

    NASA Astrophysics Data System (ADS)

    Xue, Yahui; Lv, Pengyu; Liu, Ying; Shi, Yipeng; Lin, Hao; Duan, Huiling

    2015-09-01

    Gas cavities trapped on structured hydrophobic surfaces play important roles in realizing functionalities such as superhydrophobicity, drag reduction, and surface cleaning. The morphology of the cavities exhibits strong dependence on system parameters which impact the performance of these surfaces. In this work, a complete theoretical analysis is presented to predict cavity morphological change under reduced liquid pressure, on a submerged hydrophobic surface patterned with cylindrical pores. Equilibrium solutions are derived for five different phases, namely, (I) pinned recession, (II) depinned recession, (III) Cassie-Baxter, (IV) expansion, and (V) coalescence; their stabilities are also analyzed. A phase map is developed outlining the different regimes with respect to the gas amount and liquid pressure. Importantly, phase (IV) exhibits a complex stability behavior that leads to two possible routes to coalescence, which lends two different mechanisms of cavitation. Accordingly, the threshold pressure for cavitation can be calculated. The theoretical model is supported by direct experimental measurements via confocal microscopy and demonstrates good quantitative accuracy. This work provides a predictive tool for the design of functional structured hydrophobic surfaces.

  16. Reduced airway surface pH impairs bacterial killing in the porcine cystic fibrosis lung.

    PubMed

    Pezzulo, Alejandro A; Tang, Xiao Xiao; Hoegger, Mark J; Alaiwa, Mahmoud H Abou; Ramachandran, Shyam; Moninger, Thomas O; Karp, Phillip H; Wohlford-Lenane, Christine L; Haagsman, Henk P; van Eijk, Martin; Bánfi, Botond; Horswill, Alexander R; Stoltz, David A; McCray, Paul B; Welsh, Michael J; Zabner, Joseph

    2012-07-01

    Cystic fibrosis (CF) is a life-shortening disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Although bacterial lung infection and the resulting inflammation cause most of the morbidity and mortality, how the loss of CFTR function first disrupts airway host defence has remained uncertain. To investigate the abnormalities that impair elimination when a bacterium lands on the pristine surface of a newborn CF airway, we interrogated the viability of individual bacteria immobilized on solid grids and placed onto the airway surface. As a model, we studied CF pigs, which spontaneously develop hallmark features of CF lung disease. At birth, their lungs lack infection and inflammation, but have a reduced ability to eradicate bacteria. Here we show that in newborn wild-type pigs, the thin layer of airway surface liquid (ASL) rapidly kills bacteria in vivo, when removed from the lung and in primary epithelial cultures. Lack of CFTR reduces bacterial killing. We found that the ASL pH was more acidic in CF pigs, and reducing pH inhibited the antimicrobial activity of ASL. Reducing ASL pH diminished bacterial killing in wild-type pigs, and, conversely, increasing ASL pH rescued killing in CF pigs. These results directly link the initial host defence defect to the loss of CFTR, an anion channel that facilitates HCO(3)(-) transport. Without CFTR, airway epithelial HCO(3)(-) secretion is defective, the ASL pH falls and inhibits antimicrobial function, and thereby impairs the killing of bacteria that enter the newborn lung. These findings suggest that increasing ASL pH might prevent the initial infection in patients with CF, and that assaying bacterial killing could report on the benefit of therapeutic interventions. PMID:22763554

  17. Reduced Airway Surface pH Impairs Bacterial Killing in the Porcine Cystic Fibrosis Lung

    PubMed Central

    Pezzulo, Alejandro A.; Tang, Xiao Xiao; Hoegger, Mark J.; Abou Alaiwa, Mahmoud H.; Ramachandran, Shyam; Moninger, Thomas O.; Karp, Phillip H.; Wohlford-Lenane, Christine L.; Haagsman, Henk P.; van Eijk, Martin; Bánfi, Botond; Horswill, Alexander R.; Stoltz, David A.; McCray, Paul B.; Welsh, Michael J.; Zabner, Joseph

    2012-01-01

    Cystic fibrosis (CF) is a life-shortening disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene 1. Although bacterial lung infection and the resulting inflammation cause most of the morbidity and mortality, how loss of CFTR first disrupts airway host defense has remained uncertain 2–6. We asked what abnormalities impair eradication when a bacterium lands on the pristine surface of a newborn CF airway? To investigate these defects, we interrogated the viability of individual bacteria immobilized on solid grids and placed on the airway surface. As a model we studied CF pigs, which spontaneously develop hallmark features of CF lung disease 7,8. At birth, their lungs lack infection and inflammation, but have a reduced ability to eradicate bacteria 8. Here we show that in newborn wild-type pigs, the thin layer of airway surface liquid (ASL) rapidly killed bacteria in vivo, when removed from the lung, and in primary epithelial cultures. Lack of CFTR reduced bacterial killing. We found that ASL pH was more acidic in CF, and reducing pH inhibited the antimicrobial activity of ASL. Reducing ASL pH diminished bacterial killing in wild-type pigs, and increasing ASL pH rescued killing in CF pigs. These results directly link the initial host defense defect to loss of CFTR, an anion channel that facilitates HCO3− transport 9–13. Without CFTR, airway epithelial HCO3− secretion is defective, ASL pH falls and inhibits antimicrobial function, and thereby impairs killing of bacteria that enter the newborn lung. These findings suggest that increasing ASL pH might prevent the initial infection in patients with CF and that assaying bacterial killing could report on the benefit of therapeutic interventions. PMID:22763554

  18. Reduced adhesion of macrophages on anodized titanium with select nanotube surface features

    PubMed Central

    Rajyalakshmi, Amancherla; Ercan, Batur; Balasubramanian, K; Webster, Thomas J

    2011-01-01

    One of the important prerequisites for a successful orthopedic implant apart from being osteoconductive is the elicitation of a favorable immune response that does not lead to the rejection of the implant by the host tissue. Anodization is one of the simplest surface modification processes used to create nanotextured and nanotubular features on metal oxides which has been shown to improve bone formation. Anodization of titanium (Ti) leads to the formation of TiO2 nanotubes on the surface, and the presence of these nanotubes mimics the natural nanoscale features of bone, which in turn contributes to improved bone cell attachment, migration, and proliferation. However, inflammatory cell responses on anodized Ti remains to be tested. It is hypothesized that surface roughness and surface feature size on anodized Ti can be carefully manipulated to control immune cell (specifically, macrophages) responses. Here, when Ti samples were anodized at 10 V in the presence of 1% hydrofluoric acid (HF) for 1 minute, nanotextured (nonnanotube) surfaces were created. When anodization of Ti samples was carried out with 1% HF for 10 minutes at 15 V, nanotubes with 40–50 nm diameters were formed, whereas at 20 V with 1% HF for 10 minutes, nanotubes with 60–70 nm diameters were formed. In this study, a reduced density of macrophages was observed after 24 hours of culture on nanotextured and nanotubular Ti samples which were anodized at 10, 15, and 20 V, compared with conventional unmodified Ti samples. This in vitro study thus demonstrated a reduced density of macrophages on anodized Ti, thereby providing further evidence of the greater efficacy of anodized Ti for orthopedic applications. PMID:21980239

  19. Construction of a reactive surface barrier to reduce fumigant 1,3-dichloropropene emissions.

    PubMed

    Zheng, Wei; Papiernik, Sharon K; Guo, Mingxin; Dungan, Robert S; Yates, Scott R

    2005-08-01

    Halogenated fumigants have been used extensively in production agriculture to control soilborne pests. These types of pesticides are highly volatile and are prone to affect air quality and imperil public health. In the present study, a chemical tarp approach, termed a reactive surface barrier (RSB), was developed to reduce the emission of fumigant 1,3-dichloropropene (1,3-D) from the soil surface. The agrochemicals thiourea and allylthiourea were tested as active reagents for the construction of a RSB, where these soil amendments react with 1,3-D to form nonvolatile isothiuronium ions at the soil surface and, thereby, impede fumigant emission into the atmosphere. The feasibility of the method largely depends on the reactivity of 1,3-D and the RSB agrochemicals in soil as well as on the mobility, persistence, and toxicity of the transformation products. Therefore, the reaction kinetics and transformation mechanism of 1,3-D by thiourea and allylthiourea were studied comprehensively in aqueous solution and soil. A catalytic process occurring at the surface of soil colloids facilitated the reaction between 1,3-D and thiourea in amended soils. The rate of 1,3-D transformation in thiourea-amended soil increased with decreasing soil moisture or increasing thiourea amendment level. In a field trial, a thiourea RSB reduced cumulative 1,3-D emissions by more than 80% relative to that in bare soil surface. The present results clearly indicate that this chemical remediation technology has great potential to control the emissions of volatile halogenated organic contaminants and to mitigate atmospheric pollution. PMID:16152955

  20. GABA(A) receptor alpha1 subunit mutation A322D associated with autosomal dominant juvenile myoclonic epilepsy reduces the expression and alters the composition of wild type GABA(A) receptors.

    PubMed

    Ding, Li; Feng, Hua-Jun; Macdonald, Robert L; Botzolakis, Emanuel J; Hu, Ningning; Gallagher, Martin J

    2010-08-20

    A GABA(A) receptor (GABA(A)R) alpha1 subunit mutation, A322D (AD), causes an autosomal dominant form of juvenile myoclonic epilepsy (ADJME). Previous studies demonstrated that the mutation caused alpha1(AD) subunit misfolding and rapid degradation, reducing its total and surface expression substantially. Here, we determined the effects of the residual alpha1(AD) subunit expression on wild type GABA(A)R expression to determine whether the AD mutation conferred a dominant negative effect. We found that although the alpha1(AD) subunit did not substitute for wild type alpha1 subunits on the cell surface, it reduced the surface expression of alpha1beta2gamma2 and alpha3beta2gamma2 receptors by associating with the wild type subunits within the endoplasmic reticulum and preventing them from trafficking to the cell surface. The alpha1(AD) subunit reduced surface expression of alpha3beta2gamma2 receptors by a greater amount than alpha1beta2gamma2 receptors, thus altering cell surface GABA(A)R composition. When transfected into cultured cortical neurons, the alpha1(AD) subunit altered the time course of miniature inhibitory postsynaptic current kinetics and reduced miniature inhibitory postsynaptic current amplitudes. These findings demonstrated that, in addition to causing a heterozygous loss of function of alpha1(AD) subunits, this epilepsy mutation also elicited a modest dominant negative effect that likely shapes the epilepsy phenotype. PMID:20551311

  1. Surface Expression Models for Aqueous Oceanic Activity on Titan

    NASA Astrophysics Data System (ADS)

    Clark, B.

    Drawing upon analogs from the rocky planets with geological features, subsurface acquifers and magmatism, the range of surface manifestations of a subsurface ocean on Titan comprise a series of models. Cryovolcanism of aqueous eutectics will produce flows which may be detectable as sporadic outcrops from the hydrocarbon-rich regolith, exhumed by aeolian and/or fluid processes. Solidification of extruded cryomagma, especially if containing a significant water component, should exhibit fractional crystallization of solutes in late-freeze ponds and flow fronts. Abundant higher- Z elements such as Si, S and Fe, as influenced by the Eh-pH field of the liquid phase, might be in evidence, demonstrating communication among the principal mantle components of such bodies. Consequent availability of potential nutrients and chemical energy sources would be a key indicator for habitability by chemoautolithotrophs on Titan. With near-surface mobility and sensing, LIBS as well as active and passive IR mapping spectrometry are all possible in the environment of Titan's lower atmosphere. Although some remote measurements are infeasible because of the atmosphere, near- surface naturally radioactive rock-forming elements such as K, U, and Th could be detected with gamma ray spectrometry. Touch-and-go techniques developed for small- body sampling can provide material for onboard GC, MS, XRD, microscopy and other miniaturized analytical techniques. Surface dwell times of minutes would enable contact XRF with detection of critical element ratio's such as S/Cl, K/Ca, and Mg/Si/Fe, and Raman spectroscopy for organic and mineralogical analysis, . Longer contact times would permit electromagnetic depth sounding. Many IR and particle- detection sensors operate ideally at or near the low temperatures intrinsic to the Titan atmosphere, simplifying those aspects of instrument development. Exploration of Titan by in situ and mobility techniques would capitalize on the investments and lessons

  2. Surface expression of subglacial meltwater movement, Bering Glacier, Alaska

    SciTech Connect

    Cadwell, D.H. ); Fleisher, P.J. . Dept. of Earth Sciences); Bailey, P.K. )

    1993-03-01

    Longitudinal topographic profiles (1988--1992) across the thermokarst terminus of the Grindle Hills Ice-tongue and interlobate moraine of the Bering Piedmont Glacier document annual changes in crevasse patterns and fluctuations in surface elevation related to subglacial water movement. A semi-continuous record of aerial photos (1978--1990), plus field observations (1988--1992), reveal the progressive enlargement of two lateral collapse basin on both sides of the thermokarst, connected by a transverse collapse trough. Seasonally generated meltwater at depth rises within the glacier, fills the basins and other depressions and lifts the thermokarst terminus of the ice-tongue a few meters by buoyancy and hydrostatic pressure. The resulting surface tension creates a chaotic crevasse pattern unrelated to normal glacier movement. The crevasses open (2 m wide, 8--10 m deep) in response to increased water accumulation at depth and close during subsidence as the ice-tongue settles following evacuation of subglacier water. A network of open conduits (>10 m diameter), exposed by surface ablation, provides evidence for the scale of englacial passageways beneath the thermokarst and represents a form of subglacial ablation that leads to removal of support and collapse in stagnant glacier masses.

  3. Heparin coating of tantalum coronary stents reduces surface thrombin generation but not factor IXa generation.

    PubMed

    Blezer, R; Cahalan, L; Cahalan, P T; Lindhout, T

    1998-07-01

    In the present study we used an in-vitro technique to examine initiation and propagation of blood coagulation at the surface of tantalum coronary stents exposed to flowing platelet-rich and platelet-free plasma. The time course of factor IXa production at the surface of the stent was not influenced by platelets. In spite of a significant factor IXa production, no thrombin activity was detected when the tantalum stent was exposed to platelet-free plasma; only when the stent was exposed to platelet-rich plasma was extensive thrombin production observed. These findings indicate that tantalum triggers blood coagulation, but that (adherent) platelets are essential for thrombin generation. Heparin-coated tantalum stents exposed to flowing platelet-rich plasma showed that factor IXa generation was slightly reduced compared with the bare stent. However, the heparin coating drastically delayed the onset of thrombin generation and largely reduced the steady-state production of thrombin. We found a clear relationship between the antithrombin binding capacity and the antithrombogenic potential of the heparin-coated stents. The mode of action of immobilized heparin is thought to abrogate thrombin generation by inhibiting thrombin-dependent positive feedback reactions at the surface of the coronary stent. PMID:9712292

  4. Wear-reducing Surface Functionalization of Implant Materials Using Ultrashort Laser Pulses

    NASA Astrophysics Data System (ADS)

    Oldorf, P.; Peters, R.; Reichel, S.; Schulz, A.-P.; Wendlandt, R.

    The aim of the project called "EndoLas" is the development of a reproducible and reliable method for a functionalization of articulating surfaces on hip joint endoprostheses due to a reduction of abrasion and wear by the generation of micro structures using ultrashort laser pulses. On the one hand, the microstructures shall ensure the capture of abraded particles, which cause third-body wear and thereby increase aseptic loosening. On the other hand, the structures shall improve or maintain the tribologically important lubricating film. Thereby, the cavities serve as a reservoir for the body's own synovial fluid. The dry friction, which promotes abrasion and is a part of the mixed friction in the joint, shall therefore be reduced. In experimental setups it was shown, that the abrasive wear can be reduced significantly due to micro-structuring the articulating implant surfaces. To shape the fine and deterministic cavities on the surfaces, an ultra-short pulsed laser, which is integrated in a high-precision, 5-axes micro-machining system, was used. The laser system, based on an Yb:YAG thin-disk regenerative amplifier, has an average output power of 50 W at the fundamental wavelength of 1030 nm, a maximum repetition rate of 400 kHz and a pulse duration of 6 ps. Due to this, a maximum pulse energy of 125 μJ is achievable. Furthermore external second and third harmonic generation enables the usage of wavelengths in the green and violet spectral range.

  5. Response Surface Energy Modeling of an Electric Vehicle over a Reduced Composite Drive Cycle

    SciTech Connect

    Jehlik, Forrest; LaClair, Tim J.

    2014-04-01

    Response surface methodology (RSM) techniques were applied to develop a predictive model of electric vehicle (EV) energy consumption over the Environmental Protection Agency's (EPA) standardized drive cycles. The model is based on measurements from a synthetic composite drive cycle. The synthetic drive cycle is a minimized statistical composite of the standardized urban (UDDS), highway (HWFET), and US06 cycles. The composite synthetic drive cycle is 20 minutes in length thereby reducing testing time of the three standard EPA cycles by over 55%. Vehicle speed and acceleration were used as model inputs for a third order least squared regression model predicting vehicle battery power output as a function of the drive cycle. The approach reduced three cycles and 46 minutes of drive time to a single test of 20 minutes. Application of response surface modeling to the synthetic drive cycle is shown to predict energy consumption of the three EPA cycles within 2.6% of the actual measured values. Additionally, the response model may be used to predict energy consumption of any cycle within the speed/acceleration envelope of the synthetic cycle. This technique results in reducing test time, which additionally provides a model that may be used to expand the analysis and understanding of the vehicle under consideration.

  6. Successful Surface Treatments for Reducing Instabilities in Advanced Nickel-base Superalloys for Turbine Blades

    NASA Technical Reports Server (NTRS)

    Locci, Ivan E.; MacKay, Rebecca A.; Garg, Anita; Ritzert, Frank J.

    2004-01-01

    An optimized carburization treatment has been developed to mitigate instabilities that form in the microstructures of advanced turbine airfoil materials. Current turbine airfoils consist of a single crystal superalloy base that provides the mechanical performance of the airfoil, a thermal barrier coating (TBC) that reduces the temperature of the base superalloy, and a bondcoat between the superalloy and the TBC, that improves the oxidation and corrosion resistance of the base superalloy and the spallation resistance of the TBC. Advanced nickel-base superalloys containing high levels of refractory metals have been observed to develop an instability called secondary reaction zone (SRZ), which can form beneath diffusion aluminide bondcoats. This instability between the superalloy and the bondcoat has the potential of reducing the mechanical properties of thin-wall turbine airfoils. Controlled gas carburization treatments combined with a prior stress relief heat treatment and adequate surface preparation have been utilized effectively to minimize the formation of SRZ. These additional processing steps are employed before the aluminide bondcoat is deposited and are believed to change the local chemistry and local stresses of the surface of the superalloy. This paper presents the detailed processing steps used to reduce SRZ between platinum aluminide bondcoats and advanced single crystal superalloys.

  7. Laquinimod decreases Bax expression and reduces caspase-6 activation in neurons.

    PubMed

    Ehrnhoefer, Dagmar E; Caron, Nicholas S; Deng, Yu; Qiu, Xiaofan; Tsang, Michelle; Hayden, Michael R

    2016-09-01

    Laquinimod is an immunomodulatory compound that has shown neuroprotective benefits in clinical trials for multiple sclerosis. Laquinimod ameliorates both white and gray matter damage in human patients, and prevents axonal degeneration in animal models of multiple sclerosis. Axonal damage and white matter loss are a common feature shared between different neurodegenerative diseases. Caspase-6 activation plays an important role in axonal degeneration on the molecular level. Increased activity of caspase-6 has been demonstrated in brain tissue from presymptomatic Huntington disease mutation carriers, and it is an early marker of axonal dysfunction. Since laquinimod is currently undergoing a clinical trial in Huntington disease (LEGATO-HD, clinicaltrials.gov ID: NCT02215616), we set out to evaluate its impact on neuronal caspase-6 activation. We find that laquinimod ameliorates DNA-damage induced activation of caspase-6 in primary neuronal cultures. This is an indirect effect that is not mediated by direct inhibition of the enzyme. The investigation of potential caspase-6 activating mechanisms revealed that laquinimod reduces the expression of Bax, a pro-apoptotic molecule that causes mitochondrial cytochrome c release and caspase activation. Bax expression is furthermore increased in striatal tissues from the YAC128 mouse model of HD in an age-dependent manner. Our results demonstrate that laquinimod can directly downregulate neuronal apoptosis pathways relevant for axonal degeneration in addition to its known effects on astrocytes and microglia in the CNS. It targets a pathway that is relevant for the pathogenesis of HD, supporting the hypothesis that laquinimod may provide clinical benefit. PMID:27296315

  8. Milk-soluble formula increases food intake and reduces Il6 expression in elderly rat hypothalami.

    PubMed

    Ould Hamouda, Hassina; Delplanque, Bernadette; Benomar, Yacir; Crépin, Delphine; Riffault, Laure; LeRuyet, Pascale; Bonhomme, Cécile; Taouis, Mohammed

    2015-07-01

    Malnutrition in the elderly is accompanied by several metabolic dysfunctions, especially alterations in energy homeostasis regulation and a loss of insulin responsiveness. Nutritional recommendations aim to enrich food with high protein and energy supplements, and protein composition and lipid quality have been widely studied. Despite the numerous studies that have examined attempts to overcome malnutrition in the elderly through such nutritional supplementation, it is still necessary to study the effects of a combination of protein, lipids, and vitamin D (VitD). This can be done in animal models of elderly malnutrition. In the present study, we investigated the effects of several diet formulae on insulin responsiveness, inflammation, and the hypothalamic expression of key genes that are involved in energy homeostasis control. To mimic elderly malnutrition in humans, elderly Wistar rats were food restricted (R, -50%) for 12 weeks and then refed for 4 weeks with one of four different isocaloric diets: a control diet; a diet where milk soluble protein (MSP) replaced casein; a blend of milk fat, rapeseed, and DHA (MRD); or a full formula (FF) diet that combined MSP and a blend of MRD (FF). All of the refeeding diets contained VitD. We concluded that: (i) food restriction led to the upregulation of insulin receptor in liver and adipose tissue accompanied by increased Tnfα in the hypothalamus; (ii) in all of the refed groups, refeeding led to similar body weight gain during the refeeding period; and (iii) refeeding with MSP and MRD diets induced higher food intake on the fourth week of refeeding, and this increase was associated with reduced hypothalamic interleukin 6 expression. PMID:25994005

  9. Reduced O-GlcNAcase expression promotes mitotic errors and spindle defects.

    PubMed

    Lanza, Chris; Tan, Ee Phie; Zhang, Zhen; Machacek, Miranda; Brinker, Amanda E; Azuma, Mizuki; Slawson, Chad

    2016-05-18

    Alterations in O-GlcNAc cycling, the addition and removal of O-GlcNAc, lead to mitotic defects and increased aneuploidy. Herein, we generated stable O-GlcNAcase (OGA, the enzyme that removes O-GlcNAc) knockdown HeLa cell lines and characterized the effect of the reduction in OGA activity on cell cycle progression. After release from G1/S, the OGA knockdown cells progressed normally through S phase but demonstrated mitotic exit defects. Cyclin A was increased in the knockdown cells while Cyclin B and D expression was reduced. Retinoblastoma protein (RB) phosphorylation was also increased in the knockdown compared to control. At M phase, the knockdown cells showed more compact spindle chromatids than control cells and had a greater percentage of cells with multipolar spindles. Furthermore, the timing of the inhibitory tyrosine phosphorylation of Cyclin Dependent Kinase 1 (CDK1) was altered in the OGA knockdown cells. Although expression and localization of the chromosomal passenger protein complex (CPC) was unchanged, histone H3 threonine 3 phosphorylation was decreased in one of the OGA knockdown cell lines. The Ewing Sarcoma Breakpoint Region 1 Protein (EWS) participates in organizing the CPC at the spindle and is a known substrate for O-GlcNAc transferase (OGT, the enzyme that adds O-GlcNAc). EWS O-GlcNAcylation was significantly increased in the OGA knockdown cells promoting uneven localization of the mitotic midzone. Our data suggests that O-GlcNAc cycling is an essential mechanism for proper mitotic signaling and spindle formation, and alterations in the rate of O-GlcNAc cycling produces aberrant spindles and promotes aneuploidy. PMID:27070276

  10. Prolonged high fat diet reduces dopamine reuptake without altering DAT gene expression.

    PubMed

    Cone, Jackson J; Chartoff, Elena H; Potter, David N; Ebner, Stephanie R; Roitman, Mitchell F

    2013-01-01

    The development of diet-induced obesity (DIO) can potently alter multiple aspects of dopamine signaling, including dopamine transporter (DAT) expression and dopamine reuptake. However, the time-course of diet-induced changes in DAT expression and function and whether such changes are dependent upon the development of DIO remains unresolved. Here, we fed rats a high (HFD) or low (LFD) fat diet for 2 or 6 weeks. Following diet exposure, rats were anesthetized with urethane and striatal DAT function was assessed by electrically stimulating the dopamine cell bodies in the ventral tegmental area (VTA) and recording resultant changes in dopamine concentration in the ventral striatum using fast-scan cyclic voltammetry. We also quantified the effect of HFD on membrane associated DAT in striatal cell fractions from a separate group of rats following exposure to the same diet protocol. Notably, none of our treatment groups differed in body weight. We found a deficit in the rate of dopamine reuptake in HFD rats relative to LFD rats after 6 but not 2 weeks of diet exposure. Additionally, the increase in evoked dopamine following a pharmacological challenge of cocaine was significantly attenuated in HFD relative to LFD rats. Western blot analysis revealed that there was no effect of diet on total DAT protein. However, 6 weeks of HFD exposure significantly reduced the 50 kDa DAT isoform in a synaptosomal membrane-associated fraction, but not in a fraction associated with recycling endosomes. Our data provide further evidence for diet-induced alterations in dopamine reuptake independent of changes in DAT production and demonstrates that such changes can manifest without the development of DIO. PMID:23516454

  11. Nell1-deficient mice have reduced expression of extracellular matrix proteins causing cranial and vertebral defects

    SciTech Connect

    Desai, Jayashree; Shannon, Mark E.; Johnson, Mahlon D.; Ruff, David W.; Hughes, Lori A; Kerley, Marilyn K; Carpenter, D A; Johnson, Dabney K; Rinchik, Eugene M.; Culiat, Cymbeline T

    2006-01-01

    The mammalian Nell1 gene encodes a protein kinase C-b1 (PKC-b1) binding protein that belongs to a new class of cell-signaling molecules controlling cell growth and differentiation. Over-expression of Nell1 in the developing cranial sutures in both human and mouse induces craniosynostosis, the premature fusion of the growing cranial bone fronts. Here, we report the generation, positional cloning and characterization of Nell16R, a recessive, neonatal-lethal point mutation in the mouse Nell1 gene, induced by N-ethyl-N-nitrosourea. Nell16R has a T!A base change that converts a codon for cysteine into a premature stop codon [Cys(502)Ter], resulting in severe truncation of the predicted protein product and marked reduction in steady-state levels of the transcript. In addition to the expected alteration of cranial morphology, Nell16R mutants manifest skeletal defects in the vertebral column and ribcage, revealing a hitherto undefined role for Nell1 in signal transduction in endochondral ossification. Real-time quantitative reverse transcription-PCR assays of 219 genes showed an association between the loss of Nell1 function and reduced expression of genes for extracellular matrix (ECM) proteins critical for chondrogenesis and osteogenesis. Several affected genes are involved in the human cartilage disorder Ehlers-Danlos Syndrome and other disorders associated with spinal curvature anomalies. Nell16R mutant mice are a new tool for elucidating basic mechanisms in osteoblast and chrondrocyte differentiation in the developing skull and vertebral column and understanding how perturbations in the production of ECM proteins can lead to anomalies in these structures.

  12. Targeted deletion of Secisbp2 reduces, but does not abrogate, selenoprotein expression and leads to striatal interneuron loss.

    PubMed

    Seeher, Sandra; Schweizer, Ulrich

    2014-10-01

    Selenoproteins contain the amino acid selenocysteine (Sec). The Sec insertion sequence (SECIS)-binding protein 2 (Secisbp2) binds to SECIS elements in the 3'-UTR of eukaryotic selenoprotein mRNAs. Mutations in SECISBP2 in humans lead to reduced selenoprotein expression thereby affecting thyroid hormone-dependent growth and differentiation processes. The most severe cases also display mental retardation and ataxia. Mouse models are needed to understand selenoprotein-dependent processes underlying the patients' pleiotropic phenotypes. Homozygous Secisbp2 deletion is embryonic lethal. Conditional deletion of Secisbp2 in hepatocytes significantly decreased selenoprotein expression and reduced the abundance of many, but not all, selenoprotein mRNAs. Regarding selenoprotein expression, compensatory Nrf2-dependent gene expression, or embryonic development, phenotypes were always milder in Secisbp2- than in tRNA(Sec)-deficient mice. Neuron-specific inactivation of Secisbp2 reduced cerebral expression of selenoproteins, but allowed to study the development of cortical PVpos interneurons, which are known to depend on selenoproteins. Cre expression spares the cerebellum of these mice, why we suspected that basal ganglia dysfunction may cause the obvious movement phenotype. We observed for the first time that the number of PVpos neurons was reduced by 50% in the caudate putamen of a selenoprotein-deficient mouse model. In situ hybridization for Gad67 showed that selenoprotein deficiency selectively reduced the number of PVpos GABAergic interneurons. We propose that the striatal neuron loss likely causes the movement disorder. The most striking novel finding of this work is the selective damage of PVpos/Gad67pos neurons in the striatum. The second key finding is that selenoprotein expression in hepatocytes and neurons is less dependent on Secisbp2 than on tRNA(Sec). This implies the possibility of Secisbp2-independent selenoprotein expression, albeit on a reduced level. PMID

  13. Surface-epitope masking (SEM): an immunological subtraction approach for developing monoclonal antibodies targeting surface-expressed molecules.

    PubMed

    Goldstein, Neil I; Fisher, Paul B

    2007-01-01

    An immunological subtraction approach, surface-epitope masking (SEM), is described that permits the efficient and selective production of monoclonal antibodies (MAbs) reacting with both known and unknown molecules expressed on the cell surface. The tenet underlying SEM involves blocking (masking) of shared antigens between two target populations, a "driver" and a "tester," and using appropriately modified surface-masked "tester" cells to generate MAbs reacting with surface antigens unique to the "tester population" that differentiate the two antigen sources. SEM has been employed to develop MAbs that react with the multidrug resistance surface-expressed P-glycoprotein (MDR-1) and the human interferon-gamma receptor and two potentially novel tumor-associated antigens (TAAs) expressed on the surface of prostate carcinoma and breast carcinoma cells. In principle, the SEM approach provides an uncomplicated and effective means of developing MAbs, which can also be used to identify genes, associated with important cellular processes involved in normal physiology, such as growth, aging, differentiation, and development. In addition, this strategy is amenable to produce MAbs and identify genes associated with specific disease states, including cancer, neurodegeneration, autoimmunity, and infection with pathogenic agents. PMID:18217690

  14. Two Patients with Dry Eye Disease Followed Up Using an Expression Assay of Ocular Surface Mucin

    PubMed Central

    Machida, Yumiko; Shoji, Jun; Harada, Natsuko; Inada, Noriko

    2016-01-01

    Purpose We report 2 patients with dry eye disease followed up using the expression levels of ocular surface mucin. Case Reports Patient 1: a 57-year-old woman with Sjögren's syndrome-associated dry eyes experienced severe dryness and foreign body sensation in both her eyes, and instilled sodium hyaluronate ophthalmic solution 0.3% about 10–15 times daily. We measured the expression levels of MUC5AC mRNA (MUC5AC) and MUC16 mRNA (MUC16) by using real-time reversed transcription polymerase chain reaction for the specimens of modified impression cytology. Expression levels of MUC5AC and MUC16 on her ocular surface were very low. Subjective symptoms and expression levels of ocular surface mucin improved after combined treatment of rebamipide (4 times daily) and fluorometholone (once daily) ophthalmic suspension. Patient 2: a 62-year-old man with chronic graft-versus-host disease-associated dry eye experienced severe foreign body sensation and developed superficial punctate keratopathy with mucous thread and filamentary keratitis. Expression level of MUC5AC was very high at baseline. Subjective symptoms and expression levels of ocular surface mucin improved by combined treatment of rebamipide (4 times daily) and fluorometholone (once daily) ophthalmic suspension. Conclusion Clinical test for MUC gene expression on the ocular surface was found to be useful in the follow-up of dry eye treatment. PMID:27194990

  15. Reducing premature KCC2 expression rescues seizure susceptibility and spine morphology in atypical febrile seizures.

    PubMed

    Awad, Patricia N; Sanon, Nathalie T; Chattopadhyaya, Bidisha; Carriço, Josianne Nunes; Ouardouz, Mohamed; Gagné, Jonathan; Duss, Sandra; Wolf, Daniele; Desgent, Sébastien; Cancedda, Laura; Carmant, Lionel; Di Cristo, Graziella

    2016-07-01

    Atypical febrile seizures are considered a risk factor for epilepsy onset and cognitive impairments later in life. Patients with temporal lobe epilepsy and a history of atypical febrile seizures often carry a cortical malformation. This association has led to the hypothesis that the presence of a cortical dysplasia exacerbates febrile seizures in infancy, in turn increasing the risk for neurological sequelae. The mechanisms linking these events are currently poorly understood. Potassium-chloride cotransporter KCC2 affects several aspects of neuronal circuit development and function, by modulating GABAergic transmission and excitatory synapse formation. Recent data suggest that KCC2 downregulation contributes to seizure generation in the epileptic adult brain, but its role in the developing brain is still controversial. In a rodent model of atypical febrile seizures, combining a cortical dysplasia and hyperthermia-induced seizures (LHS rats), we found a premature and sustained increase in KCC2 protein levels, accompanied by a negative shift of the reversal potential of GABA. In parallel, we observed a significant reduction in dendritic spine size and mEPSC amplitude in CA1 pyramidal neurons, accompanied by spatial memory deficits. To investigate whether KCC2 premature overexpression plays a role in seizure susceptibility and synaptic alterations, we reduced KCC2 expression selectively in hippocampal pyramidal neurons by in utero electroporation of shRNA. Remarkably, KCC2 shRNA-electroporated LHS rats show reduced hyperthermia-induced seizure susceptibility, while dendritic spine size deficits were rescued. Our findings demonstrate that KCC2 overexpression in a compromised developing brain increases febrile seizure susceptibility and contribute to dendritic spine alterations. PMID:26875662

  16. Modulation of APP Expression Reduces Aβ Deposition in a Mouse Model

    PubMed Central

    Asuni, Ayodeji A.; Guridi, Maitea; Pankiewicz, Joanna E.; Sanchez, Sandrine; Sadowski, Martin J.

    2014-01-01

    Objective Proteolytic cleavage of the amyloid precursor protein (APP) generates β-amyloid (Aβ) peptides. Prolonged accumulation of Aβ in the brain underlies the pathogenesis of Alzheimer’s disease (AD) and is regarded as a principal target for development of disease-modifying therapeutics. Methods Using CHO APP751SW cells we identified and characterized effects of 2-[(pyridine-2-ylmethyl)-amino]-phenol (2-PMAP) on APP steady-state level and Aβ production. Outcomes of 2-PMAP treatment on Aβ accumulation and associated memory deficit were studied in APPSW/PS1dE9 AD transgenic model mice. Results In CHO APP751SW cells, 2-PMAP in a dose-response manner lowered the steady-state APP level and inhibited Aβx-40 and Aβx-42 production with minimum effective concentration ≤0.5μM. The inhibitory effect of 2-PMAP on translational efficiency of APP mRNA into protein was directly confirmed using 35S-methionine/cysteine metabolic labeling technique, while APP mRNA level remained unaltered. Administration of 2-PMAP to APPSW/PS1dE9 mice reduced brain levels of full length APP and its C-terminal fragments along with lowering levels of soluble Aβx-40 and Aβx-42. Four-month chronic treatment of APPSW/PS1dE9 mice revealed no observable toxicity and improved animals’ memory performance. 2-PMAP treatment also caused significant reduction in brain Aβ deposition determined by both unbiased quantification of Aβ plaque load and biochemical analysis of formic acid extracted Aβx-40 and Aβx-42 levels and the level of oligomeric Aβ. Interpretation We demonstrate the potential of modulating APP steady-state expression level as a safe and effective approach for reducing Aβ deposition in AD transgenic model mice. PMID:24687915

  17. Reduced cortical thickness, surface area in patients with chronic obstructive pulmonary disease: a surface-based morphometry and neuropsychological study.

    PubMed

    Chen, Ji; Lin, In-Tsang; Zhang, Haiyan; Lin, Jianzhong; Zheng, Shili; Fan, Ming; Zhang, Jiaxing

    2016-06-01

    Neural impairments accompanying chronic obstructive pulmonary disease (COPD) have received growing research attention. Previous neuroimaging studies exclusively used volumetric methods to measure cortical volume as a whole rather than focusing on anatomical and neuropathological distinct indices. Here we decomposed the cortical architecture into cortical thickness (CTh), surface area (SA), and gyrification, for the first time, to provide a more integrative profile of brain damage in COPD. Clinical T1-weighted MRI scans were acquired in 25 stable COPD patients (mean age 69) and 25 age-matched controls. Images were processed using surface-based morphometry to obtain cortical parameters enabling more accurate measurement in deep sulci and localized regional mapping. Demographic, physiological, and cognitive assessments were made and correlated with cortical indices. Compared to controls, COPD patients showed significantly reduced CTh broadly distributed in motor, parietal, and prefrontal cortices, together with more circumscribed SA reduction in dorsomedial prefrontal cortex and Broca's area (cluster-level P < 0.05 corrected). No abnormal gyrification was detected. Decreased CTh in parietofrontal networks strongly correlated with visuospatial construction impairment in COPD patients. Furthermore, thinner dorsolateral prefrontal cortex (DLPFC) best predicted poorer performance (r (2)  = 0.315, P = 0.004), and was associated with lower arterial oxygen saturation. These data indicate that cortical thinning is a key morphologic feature associated with COPD that could be partly attributed to oxygen desaturation and contributes to COPD visual memory and drawing deficits. Surface-based morphometry provides valuable information concerning COPD, and could ultimately help us to characterize the neurodegenerative pattern and to clarify neurologic mechanisms underlying cognitive dysfunction in COPD patients. PMID:25986304

  18. Superparamagnetic Reduced Graphene Oxide with Large Magnetoresistance: A Surface Modulation Strategy.

    PubMed

    Peng, Jing; Guo, Yuqiao; Lv, Haifeng; Dou, Xinyu; Chen, Qi; Zhao, Jiyin; Wu, Changzheng; Zhu, Xiaojiao; Lin, Yue; Lu, Wei; Wu, Xiaojun; Xie, Yi

    2016-02-24

    The graphene system is actively pursued in spintronics for its nontrivial sp electron magnetism and its potential for the flexible surface chemical tuning of magnetoelectronic functionality. The magnetoresistance (MR) of graphene can be effectively tuned under high magnetic fields at cryogenic temperatures, but it remains a challenge to achieve sensitive magnetoelectric response under ambient conditions. We report the use of surface modulation to realize superparamagnetism in reduced graphene oxide (rGO) with sensitive magnetic field response. The superparamagnetic rGO was obtained by a mild oxidation process to partially remove the thiol groups covalently bound to the carbon framework, which brings about large low-field negative MR at room temperature (-8.6 %, 500 Oe, 300 K). This strategy provides a new approach for optimizing the intrinsic magnetoelectric properties of two-dimensional materials. PMID:26822504

  19. Vibration of structures containing compressible liquids with surface tension and sloshing effects. Reduced-order model

    NASA Astrophysics Data System (ADS)

    Ohayon, R.; Soize, C.

    2015-06-01

    This paper deals with the development of the linear vibration of a general viscoelastic structure, with a local wall acoustic impedance, containing an inviscid compressible liquid (but with an additional volume dissipative term), with surface tension (capillarity) and sloshing effects, and neglecting the effects of internal gravity waves and the elastogravity operator. The sloshing problems of incompressible liquids with capillarity effects in elastic structures exhibit a major difficulty induced by the boundary contact conditions on the triple line because the capillarity forces are forces per unit length while the elastic forces are forces per unit surface. The proposed framework has the following novel features: (i) introducing a new appropriate boundary condition for the contact angle condition compatible with a deformable structure considered here as viscoelastic, (ii) considering a compressible liquid while incompressibility hypothesis is generally used for FSI problems including capillarity phenomena, and (iii) constructing a reduced-order model for the computational coupled problem.

  20. Interface and transport phenomena under reduced gravity. II - Surfaces and wetting

    NASA Astrophysics Data System (ADS)

    Bewersdorff, A.; Mueller, G.; Oertel, H., Jr.; Sahm, P. R.; Sell, P.-J.; Siekmann, J.

    1983-02-01

    Liquids contained in propellant tanks under microgravity conditions are subject to reduced gravity forces, surface forces and boundary adhesion. Based on the principle of the minimum of the total potential energy, the basic equations of capillary hydrostatics are derived and the equilibrium configurations of the free fluid surface in rotationally symmetric containers are calculated. Tank geometries for technical purposes are discussed, as well as the role of outgassing of molten matter in materials processing in space. The Hele-Shaw cell is described as a simple and reliable instrument for terrestrial experiments on bubble dynamics under simulated microgravity and temperature gradients. Finally, the wetting kinetics of model tubes under simulated gravity and microgravity is examined.

  1. Femtosecond laser full and partial texturing of steel surfaces to reduce friction in lubricated contact

    NASA Astrophysics Data System (ADS)

    Ancona, Antonio; Carbone, Giuseppe; De Filippis, Michele; Volpe, Annalisa; Lugarà, Pietro Mario

    2014-12-01

    Minimizing mechanical losses and friction in vehicle engines would have a great impact on reducing fuel consumption and exhaust emissions, to the benefit of environmental protection. With this scope, laser surface texturing (LST) with femtosecond pulses is an emerging technology, which consists of creating, by laser ablation, an array of high-density microdimples on the surface of a mechanical device. The microtexture decreases the effective contact area and, in case of lubricated contact, acts as oil reservoir and trap for wear debris, leading to an overall friction reduction. Depending on the lubrication regime and on the texture geometry, several mechanisms may concur to modify friction such as the local reduction of the shear stress, the generation of a hydrodynamic lift between the surfaces or the formation of eddy-like flows at the bottom of the dimple cavities. All these effects have been investigated by fabricating and characterizing several LST surfaces by femtosecond laser ablation with different features: partial/full texture, circular/elliptical dimples, variable diameters, and depths but equivalent areal density. More than 85% of friction reduction has been obtained from the circular dimple geometry, but the elliptical texture allows adjusting the friction coefficient by changing its orientation with respect to the sliding direction.

  2. Reducing intrinsic loss in superconducting resonators by surface treatment and deep etching of silicon substrates

    SciTech Connect

    Bruno, A.; Lange, G. de; Asaad, S.; Enden, K. L. van der; Langford, N. K.; DiCarlo, L.

    2015-05-04

    We present microwave-frequency NbTiN resonators on silicon, systematically achieving internal quality factors above 1 M in the quantum regime. We use two techniques to reduce losses associated with two-level systems: an additional substrate surface treatment prior to NbTiN deposition to optimize the metal-substrate interface and deep reactive-ion etching of the substrate to displace the substrate-vacuum interfaces away from high electric fields. The temperature and power dependence of resonator behavior indicate that two-level systems still contribute significantly to energy dissipation, suggesting that more interface optimization could further improve performance.

  3. Surface functionalities of gold nanoparticles impact embryonic gene expression responses

    PubMed Central

    Truong, Lisa; Tilton, Susan C.; Zaikova, Tatiana; Richman, Erik; Waters, Katrina M.; Hutchison, James E.; Tanguay, Robert L.

    2012-01-01

    Incorporation of gold nanoparticles (AuNPs) into consumer products is increasing; however, there is a gap in available toxicological data to determine the safety of AuNPs. In this study, we utilised the embryonic zebrafish to investigate how surface functionalisation and charge influence molecular responses. Precisely engineered AuNPs with 1.5 nm cores were synthesised and functionalized with three ligands: 2-mercaptoethanesulfonic acid (MES), N,N,N-trimethylammoniumethanethiol (TMAT), or 2-(2-(2-mercaptoethoxy)ethoxy)ethanol. Developmental assessments revealed differential biological responses when embryos were exposed to the functionalised AuNPs at the same concentration. Using inductively coupled plasma–mass spectrometry, AuNP uptake was confirmed in exposed embryos. Following exposure to MES- and TMAT-AuNPs from 6 to 24 or 6 to 48 h post fertilisation, pathways involved in inflammation and immune response were perturbed. Additionally, transport mechanisms were misregulated after exposure to TMAT and MES-AuNPs, demonstrating that surface functionalisation influences many molecular pathways. PMID:22263968

  4. Proinflammatory Cytokine Gene Expression by Murine Macrophages in Response to Brugia malayi Wolbachia Surface Protein

    PubMed Central

    Porksakorn, Chantima; Nuchprayoon, Surang; Park, Kiwon; Scott, Alan L.

    2007-01-01

    Wolbachia, an endosymbiotic bacterium found in most species of filarial parasites, is thought to play a significant role in inducing innate inflammatory responses in lymphatic filariasis patients. However, the Wolbachia-derived molecules that are recognized by the innate immune system have not yet been identified. In this study, we exposed the murine macrophage cell line RAW 264.7 to a recombinant form of the major Wolbachia surface protein (rWSP) to determine if WSP is capable of innately inducing cytokine transcription. Interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF) mRNAs were all upregulated by the rWSP stimulation in a dose-dependant manner. TNF transcription peaked at 3 hours, whereas IL-1β and IL-6 transcription peaked at 6 hours post-rWSP exposure. The levels of innate cytokine expression induced by a high-dose (9.0 μg/mL) rWSP in the RAW 264.7 cells were comparable to the levels induced by 0.1 μg/mL E. coli-derived lipopolysaccharides. Pretreatment of the rWSP with proteinase-K drastically reduced IL-1β, IL-6, and TNF transcription. However, the proinflammatory response was not inhibited by polymyxin B treatment. These results strongly suggest that the major Wolbachia surface protein molecule WSP is an important inducer of innate immune responses during filarial infections. PMID:17641731

  5. Embryo Microinjection of Selenomethionine Reduces Hatchability and Modifies Oxidant Responsive Gene Expression in Zebrafish

    NASA Astrophysics Data System (ADS)

    Thomas, J. K.; Janz, D. M.

    2016-05-01

    In previous studies we demonstrated that exposure to selenomethionine (SeMet) causes developmental toxicities in zebrafish (Danio rerio). The objectives of this study were to establish a dose-response relationship for developmental toxicities in zebrafish after embryo microinjection of Se (8, 16 or 32 μg/g dry mass of eggs) in the form of SeMet, and to investigate potential underlying mechanism(s) of SeMet-induced developmental toxicities. A dose-dependent increase in frequencies of mortality and total deformities, and reduced hatchability were observed in zebrafish exposed to excess Se via embryo microinjection. The egg Se concentration causing 20% mortality was then used to investigate transcript abundance of proteins involved in antioxidant protection and methylation. Excess Se exposure modified gene expression of oxidant-responsive transcription factors (nuclear factor erythroid 2-related factor nrf2a and nrf2b), and enzymes involved in cellular methylation (methionine adenosyltransferase mat1a and mat2ab) in zebrafish larvae. Notably, excess Se exposure up-regulated transcript abundance of aryl hydrocarbon receptor 2 (ahr2), a signalling pathway involved in the toxicity of dioxin-related compounds. Our findings suggest that oxidative stress or modification of methylation, or a combination of these mechanisms, might be responsible for Se-induced developmental toxicities in fishes.

  6. Protein-poor diet reduces host-specific immune gene expression in Bombus terrestris

    PubMed Central

    Brunner, Franziska S.; Schmid-Hempel, Paul; Barribeau, Seth M.

    2014-01-01

    Parasites infect hosts non-randomly as genotypes of hosts vary in susceptibility to the same genotypes of parasites, but this specificity may be modulated by environmental factors such as nutrition. Nutrition plays an important role for any physiological investment. As immune responses are costly, resource limitation should negatively affect immunity through trade-offs with other physiological requirements. Consequently, nutritional limitation should diminish immune capacity in general, but does it also dampen differences among hosts? We investigated the effect of short-term pollen deprivation on the immune responses of our model host Bombus terrestris when infected with the highly prevalent natural parasite Crithidia bombi. Bumblebees deprived of pollen, their protein source, show reduced immune responses to infection. They failed to upregulate a number of genes, including antimicrobial peptides, in response to infection. In particular, they also showed less specific immune expression patterns across individuals and colonies. These findings provide evidence for how immune responses on the individual-level vary with important elements of the environment and illustrate how nutrition can functionally alter not only general resistance, but also alter the pattern of specific host–parasite interactions. PMID:24850921

  7. Reduced expression of ribosomal proteins relieves microRNA-mediated repression.

    PubMed

    Janas, Maja M; Wang, Eric; Love, Tara; Harris, Abigail S; Stevenson, Kristen; Semmelmann, Karlheinz; Shaffer, Jonathan M; Chen, Po-Hao; Doench, John G; Yerramilli, Subrahmanyam V B K; Neuberg, Donna S; Iliopoulos, Dimitrios; Housman, David E; Burge, Christopher B; Novina, Carl D

    2012-04-27

    MicroRNAs (miRNAs) regulate physiological and pathological processes by inducing posttranscriptional repression of target messenger RNAs (mRNAs) via incompletely understood mechanisms. To discover factors required for human miRNA activity, we performed an RNAi screen using a reporter cell line of miRNA-mediated repression of translation initiation. We report that reduced expression of ribosomal protein genes (RPGs) dissociated miRNA complexes from target mRNAs, leading to increased polysome association, translation, and stability of miRNA-targeted mRNAs relative to untargeted mRNAs. RNA sequencing of polysomes indicated substantial overlap in sets of genes exhibiting increased or decreased polysomal association after Argonaute or RPG knockdowns, suggesting similarity in affected pathways. miRNA profiling of monosomes and polysomes demonstrated that miRNAs cosediment with ribosomes. RPG knockdowns decreased miRNAs in monosomes and increased their target mRNAs in polysomes. Our data show that most miRNAs repress translation and that the levels of RPGs modulate miRNA-mediated repression of translation initiation. PMID:22541556

  8. Embryo Microinjection of Selenomethionine Reduces Hatchability and Modifies Oxidant Responsive Gene Expression in Zebrafish

    PubMed Central

    Thomas, J. K.; Janz, D. M.

    2016-01-01

    In previous studies we demonstrated that exposure to selenomethionine (SeMet) causes developmental toxicities in zebrafish (Danio rerio). The objectives of this study were to establish a dose-response relationship for developmental toxicities in zebrafish after embryo microinjection of Se (8, 16 or 32 μg/g dry mass of eggs) in the form of SeMet, and to investigate potential underlying mechanism(s) of SeMet-induced developmental toxicities. A dose-dependent increase in frequencies of mortality and total deformities, and reduced hatchability were observed in zebrafish exposed to excess Se via embryo microinjection. The egg Se concentration causing 20% mortality was then used to investigate transcript abundance of proteins involved in antioxidant protection and methylation. Excess Se exposure modified gene expression of oxidant-responsive transcription factors (nuclear factor erythroid 2-related factor nrf2a and nrf2b), and enzymes involved in cellular methylation (methionine adenosyltransferase mat1a and mat2ab) in zebrafish larvae. Notably, excess Se exposure up-regulated transcript abundance of aryl hydrocarbon receptor 2 (ahr2), a signalling pathway involved in the toxicity of dioxin-related compounds. Our findings suggest that oxidative stress or modification of methylation, or a combination of these mechanisms, might be responsible for Se-induced developmental toxicities in fishes. PMID:27210033

  9. Increased Expression of Alpha-Synuclein Reduces Neurotransmitter Release by Inhibiting Synaptic Vesicle Reclustering After Endocytosis

    PubMed Central

    Nemani, Venu M.; Lu, Wei; Berge, Victoria; Nakamura, Ken; Onoa, Bibiana; Lee, Michael K.; Chaudhry, Farrukh A.; Nicoll, Roger A.; Edwards, Robert H.

    2011-01-01

    Summary The protein α-synuclein accumulates in the brain of patients with sporadic Parkinson’s disease (PD), and increased gene dosage causes a severe, dominantly inherited form of PD, but we know little about the effects of synuclein that precede degeneration. α-Synuclein localizes to the nerve terminal, but the knockout has little if any effect on synaptic transmission. In contrast, we now find that the modest over-expression of α-synuclein, in the range predicted for gene multiplication and in the absence of overt toxicity, markedly inhibits neurotransmitter release. The mechanism, elucidated by direct imaging of the synaptic vesicle cycle, involves a specific reduction in size of the synaptic vesicle recycling pool. Ultrastructural analysis demonstrates reduced synaptic vesicle density at the active zone, and imaging further reveals a defect in the reclustering of synaptic vesicles after endocytosis. Increased levels of α-synuclein thus produce a specific, physiological defect in synaptic vesicle recycling that precedes detectable neuropathology. PMID:20152114

  10. Altered CD94/NKG2A and perforin expression reduce the cytotoxic activity in malignant pleural effusions.

    PubMed

    Pace, Elisabetta; Di Sano, Caterina; Ferraro, Maria; Tipa, Annalisa; Olivieri, Dario; Spatafora, Mario; Santagata, Roberta; Bellia, Vincenzo; Gjomarkaj, Mark

    2011-01-01

    CD94/NKG2A is an inhibitory receptor expressed by NK cells and cytotoxic lymphocytes and, upon activation by HLA-E, downregulates the cytolytic activities of these cells thus representing a tumour immune escape mechanism. This study was aimed at assessing whether cytotoxic lymphocytes (CD8+) and NK cells from malignant pleural effusions have a deregulated expression of CD94/NKG2A. The expression of membrane CD94/NKG2A and perforin was evaluated by flow-cytometry in CD8+ and NK cells from pleural effusions and autologous peripheral blood of cancer (n=19) and congestive heart failure (CHF) (n=11) patients. Intracellular CD94/NKG2A expression was evaluated by flow-cytometry in pleural effusion CD8+ and NK cells from cancer patients (n=10). Cytotoxic activity against cancer cells exerted by pleural and autologous peripheral blood T lymphocytes from cancer patients was assessed by flow-cytometry assay. Pleural CD8+ from cancer patients showed a reduced expression of membrane CD94/NKG2A and perforin when compared to autologous peripheral blood and CHF pleural effusions. Reduced numbers of NK cells were present in pleural effusions from both cancer and CHF patients. Pleural NK from cancer patients showed a reduced expression of membrane CD94/NKG2A and perforin when compared to autologous peripheral blood. Pleural T lymphocytes from cancer patients exhibited a reduced cytotoxic activity against cancer cells when compared to autologous peripheral blood T lymphocytes. The intracellular expression of CD94/NKG2A in CD8+ and NK cells from cancer patients was higher than membrane expression. In conclusion, this study provides compelling evidences of new mechanisms underlying the reduced host defence against cancer within the pleural space. PMID:20932742

  11. Targeted Surface Expression of an Exogenous Antigen in Stably Transfected Babesia bovis

    PubMed Central

    Laughery, Jacob M.; Knowles, Donald P.; Schneider, David A.; Bastos, Reginaldo G.; McElwain, Terry F.; Suarez, Carlos E.

    2014-01-01

    Babesia bovis is a tick-borne intraerythocytic protozoan responsible for acute disease in cattle which can be controlled by vaccination with attenuated B. bovis strains. Emerging B. bovis transfection technologies may increase the usefulness of these live vaccines. One use of transfected B. bovis parasites may be as a vaccine delivery platform. Previous transfection methods for B. bovis were limited by single expression sites and intracellular expression of transfected antigens. This study describes a novel transfection system in which two exogenous genes are expressed: one for selection and the other for a selected antigen designed to be delivered to the surface of the parasites. The strategy for duplicating the number of transfected genes was based on the use of the putative bidirectional promoter of the B. bovis 1.4 Kb ef-1α intergenic region. The ability of this region to regulate two independent expression sites was demonstrated using a luciferase assay on transiently transfected B. bovis parasites and then incorporated into a stable transfection plasmid to control independent expression of the selectable marker GFP-BSD and another gene of interest. A chimeric gene was synthetized using sequences from the protective B-cell epitopes of Rhipicephalus microplus tick antigen Bm86 along with sequences from the surface exposed B. bovis major surface antigen-1. This chimeric gene was then cloned into the additional expression site of the transfection plasmid. Transfection of the B. bovis Mo7 strain with this plasmid resulted in stable insertion into the ef-1α locus and simultaneous expression of both exogenous genes. Expression of the Bm86 epitopes on the surface of transfected merozoites was demonstrated using immunofluorescence analyses. The ability to independently express multiple genes by the inclusion of a bidirectional promoter and the achievement of surface expression of foreign epitopes advances the potential of transfected B. bovis as a future vaccine

  12. Targeted surface expression of an exogenous antigen in stably transfected Babesia bovis.

    PubMed

    Laughery, Jacob M; Knowles, Donald P; Schneider, David A; Bastos, Reginaldo G; McElwain, Terry F; Suarez, Carlos E

    2014-01-01

    Babesia bovis is a tick-borne intraerythocytic protozoan responsible for acute disease in cattle which can be controlled by vaccination with attenuated B. bovis strains. Emerging B. bovis transfection technologies may increase the usefulness of these live vaccines. One use of transfected B. bovis parasites may be as a vaccine delivery platform. Previous transfection methods for B. bovis were limited by single expression sites and intracellular expression of transfected antigens. This study describes a novel transfection system in which two exogenous genes are expressed: one for selection and the other for a selected antigen designed to be delivered to the surface of the parasites. The strategy for duplicating the number of transfected genes was based on the use of the putative bidirectional promoter of the B. bovis 1.4 Kb ef-1α intergenic region. The ability of this region to regulate two independent expression sites was demonstrated using a luciferase assay on transiently transfected B. bovis parasites and then incorporated into a stable transfection plasmid to control independent expression of the selectable marker GFP-BSD and another gene of interest. A chimeric gene was synthetized using sequences from the protective B-cell epitopes of Rhipicephalus microplus tick antigen Bm86 along with sequences from the surface exposed B. bovis major surface antigen-1. This chimeric gene was then cloned into the additional expression site of the transfection plasmid. Transfection of the B. bovis Mo7 strain with this plasmid resulted in stable insertion into the ef-1α locus and simultaneous expression of both exogenous genes. Expression of the Bm86 epitopes on the surface of transfected merozoites was demonstrated using immunofluorescence analyses. The ability to independently express multiple genes by the inclusion of a bidirectional promoter and the achievement of surface expression of foreign epitopes advances the potential of transfected B. bovis as a future vaccine

  13. Synthetic Strategies for Semiconductor Nanocrystals Expressing Localized Surface Plasmon Resonance.

    PubMed

    Niezgoda, J Scott; Rosenthal, Sandra J

    2016-03-01

    The field of semiconductor plasmonics has grown rapidly since its outset, only roughly six years ago, and now includes many crystalline substances ranging from GeTe to wide-bandgap transition-metal oxides. One byproduct of this proliferation is the sea of differing synthetic methods to realize localized surface plasmon resonances (LSPRs) based on the studied material. Strategies vary widely from material to material, but all have the common goal of introducing extremely high carrier densities to the semiconductor system. This doping results in tunable, size-quantized, and on/off-switchable LSPR modes, which are a complete departure from traditional metal-nanoparticle-based plasmon resonances. This Minireview will provide an overview of the current state of nanocrystal and quantum-dot plasmonics and the physical basis thereof, however its main purpose is to summarize the methods for realizing LSPRs in the various syntheses and systems that have been reported to date. PMID:26530667

  14. Mars Express scientists find a different Mars underneath the surface

    NASA Astrophysics Data System (ADS)

    2006-12-01

    Observations by MARSIS, the first subsurface sounding radar used to explore a planet, strongly suggest that ancient impact craters lie buried beneath the smooth, low plains of Mars' northern hemisphere. The technique uses echoes of radio waves that have penetrated below the surface. MARSIS found evidence that these buried impact craters - ranging from about 130 to 470 kilometres in diameter - are present under much of the northern lowlands. The findings appear in the 14 December 2006 issue of the journal Nature. With MARSIS "it's almost like having X-ray vision," said Thomas R. Watters of the National Air and Space Museum's Center for Earth and Planetary Studies, Washington, and lead author of the results. "Besides finding previously unknown impact basins, we've also confirmed that some subtle, roughly circular, topographic depressions in the lowlands are related to impact features." Studies of how Mars evolved help in understanding early Earth. Some signs of the forces at work a few thousand million years ago are harder to detect on Earth because many of them have been obliterated by tectonic activity and erosion. The new findings bring planetary scientists closer to understanding one of the most enduring mysteries about the geological evolution and history of Mars. In contrast to Earth, Mars shows a striking difference between its northern and southern hemispheres. Almost the entire southern hemisphere has rough, heavily cratered highlands, while most of the northern hemisphere is smoother and lower in elevation. Since the impacts that cause craters can happen anywhere on a planet, the areas with fewer craters are generally interpreted as younger surfaces where geological processes have erased the impact scars. The surface of Mars' northern plains is young and smooth, covered by vast amounts of volcanic lava and sediment. However, the new MARSIS data indicate that the underlying crust is extremely old. “The number of buried impact craters larger than 200

  15. Prognostic significance of reduced immunohistochemical expression of E-cadherin in endometrial cancer-results of a meta-analysis

    PubMed Central

    Zheng, Xing; Du, Xue-Lian; Jiang, Tao

    2015-01-01

    Objective: Previous studies which investigated the relationship between reduced E-cadherin and prognosis of endometrial cancer were ambiguous and conflicting. Therefore, the aim of the present study was to evaluate the relationship between reduced expression of E-cadherin and endometrial cancer by meta-analysis approach. Method: AfterPubmed and Embasewere deliberately searched via the internet, 8 pieces of literaturewere totally included in final meta-analysis. After the data had been abstracted, the pulled odds ratio (OR) and hazard ratio (HR) were calculated by STATA with random or fixed effect model depending on their heterogeneity. The publication bias of included literature were tested by Begg’s funnel plot and Egger’s test. Results: The pulled data showed that the reduced expression of E-cadherin was significantly associated with overall survival (OS), HR=2.42, 95% CI: 1.50-3.89. The clinical parameters such as lymph node metastasis (LNM), myometrial invasion (MI), International Federation of Gynecology and Obstetrics (FIGO) stage, histological type and pathological type were also significantly associated with reduced expression of E-cadherin. The results of publication biasshowed there were no significant publication bias. Conclusion: Endometrial cancer patients with reduced expression of E-cadherin may have a poorer prognosis than those with normal or higher expression of E-cadherin. PMID:26770483

  16. Carbon monoxide down-modulates Toll-like receptor 4/MD2 expression on innate immune cells and reduces endotoxic shock susceptibility

    PubMed Central

    Riquelme, Sebastián A; Bueno, Susan M; Kalergis, Alexis M

    2015-01-01

    Carbon monoxide (CO) has been recently reported as the main anti-inflammatory mediator of the haem-degrading enzyme haem-oxygenase 1 (HO-1). It has been shown that either HO-1 induction or CO treatment reduces the ability of monocytes to respond to inflammatory stimuli, such as lipopolysaccharide (LPS), due to an inhibition of the signalling pathways leading to nuclear factor-κB, mitogen-activated protein kinases and interferon regulatory factor 3 activation. Hence, it has been suggested that CO impairs the stimulation of the Toll-like receptor 4 (TLR4)/myeloid differentiation factor-2 (MD2) complex located on the surface of immune cells. However, whether CO can negatively modulate the surface expression of the TLR4/MD2 complex in immune cells remains unknown. Here we report that either HO-1 induction or treatment with CO decreases the surface expression of TLR4/MD2 in dendritic cells (DC) and neutrophils. In addition, in a septic shock model of mice intraperitoneally injected with lipopolysaccharide (LPS), prophylactic treatment with CO protected animals from hypothermia, weight loss, mobility loss and death. Further, mice pre-treated with CO and challenged with LPS showed reduced recruitment of DC and neutrophils to peripheral blood, suggesting that this gas causes a systemic tolerance to endotoxin challenge. No differences in the amount of innate cells in lymphoid tissues were observed in CO-treated mice. Our results suggest that CO treatment reduces the expression of the TLR4/MD2 complex on the surface of myeloid cells, which renders them resistant to LPS priming in vitro, as well as in vivo in a model of endotoxic shock. PMID:25179131

  17. Norepinephrine Reduces Reactive Oxygen Species (ROS) and DNA Damage in Ovarian Surface Epithelial Cells

    PubMed Central

    Patel, Pooja R; Hegde, Muralidhar L; Theruvathu, Jacob; Mitra, Sankar A; Boldogh, Istvan; Sowers, Lawrence

    2015-01-01

    Objective To determine the role of norepinephrine (NE) on DNA damage and reactive oxygen species (ROS) generation in ovarian surface epithelial cells. Method Non-tumorigenic, immortalized ovarian surface epithelial cells were treated with NE, bleomycin, and bleomycin followed by NE. The comet assay was performed on each treatment group to determine the amount of single and double-strand breaks induced by treatments. ROS levels for each treatment group were measured using the H2DCF-DA fluorescence assay. Finally, RNA transcripts were measured for each treatment group with regards to the expression of DNA repair and oxidative stress genes. Results The mean tail moment of untreated cells was significantly greater than that of cells treated with NE (p=0.02). The mean tail moment of cells treated with bleomycin was significantly greater than that of cells treated with bleomycin followed by NE (p<0.01). Treatment with NE resulted in significantly less ROS generation than in untreated cells (p<0.01). NE treatment after hydrogen peroxide treatment resulted in a noticeable decrease in ROS generation. Genes associated with oxidative stress were upregulated in cells treated with bleomycin, however this upregulation was blunted when bleomycin-treated cells were treated subsequently with NE. Conclusion NE is associated with decreased DNA damage and ROS production in ovarian surface epithelial cells. This effect is protective in the presence of the oxidative-damaging agent bleomycin. These results suggest an additional physiologic role for the stress hormone NE, in protecting ovarian surface epithelial cells from oxidative stress. PMID:26167254

  18. VARIABLE BOUND-SITE CHARGING CONTRIBUTIONS TO SURFACE COMPLEXATION MASS ACTION EXPRESSIONS

    EPA Science Inventory

    One and two pK models of surface complexation reactions between reactive surface sites (>SOH) and the proton (H+) use mass action expressions of the form: Ka={[>SOHn-1z-1]g>SOH(0-1)aH+EXP(-xeY/kT)}/{[>SOHnz]g>SOH(n)} where Ka=the acidity constant, [ ]=reactive species concentrati...

  19. Targeting ID2 expression triggers a more differentiated phenotype and reduces aggressiveness in human salivary gland cancer cells.

    PubMed

    Sumida, Tomoki; Ishikawa, Akiko; Nakano, Hiroyuki; Yamada, Tomohiro; Mori, Yoshihide; Desprez, Pierre-Yves

    2016-08-01

    Inhibitors of DNA-binding (ID) proteins are negative regulators of basic helix-loop-helix transcription factors and generally stimulate cell proliferation and inhibit differentiation. We previously determined that ID1 was highly expressed in aggressive salivary gland cancer (SGC) cells in culture. Here, we show that ID2 is also expressed in aggressive SGC cells. ID2 knockdown triggers important changes in cell behavior, that is, it significantly reduces the expression of N-cadherin, vimentin and Snail, induces E-cadherin expression and leads to a more differentiated phenotype exemplified by changes in cell shape. Moreover, ID2 knockdown almost completely suppresses invasion and the expression of matrix metalloproteinase 9. In conclusion, ID2 expression maintains an aggressive phenotype in SGC cells, and ID2 repression triggers a reduction in cell aggressiveness. ID2 therefore represents a potential therapeutic target during SGC progression. ID proteins are negative regulators of basic helix-loop-helix transcription factors and generally stimulate cell proliferation and inhibit differentiation. ID2 knockdown triggers important changes in cell behavior, that is, it significantly reduces the expression of N-cadherin, vimentin and Snail, induces E-cadherin expression and leads to a more differentiated phenotype exemplified by changes in cell shape. ID2 therefore represents a potential therapeutic target during SGC progression. PMID:27364596

  20. A novel allele of Alx4 results in reduced Fgf10 expression and failure of eyelid fusion in mice.

    PubMed

    Curtain, Michelle; Heffner, Caleb S; Maddox, Dennis M; Gudis, Polyxeni; Donahue, Leah Rae; Murray, Stephen A

    2015-04-01

    Normal fusion of developing eyelids requires coordination of inductive signals from the eyelid mesenchyme with migration of the periderm cell layer and constriction of the eyelids across the eye. Failure of this process results in an eyelids open at birth (EOB) phenotype in mice. We have identified a novel spontaneous allele of Alx4 that displays EOB, in addition to polydactyly and cranial malformations. Alx4 is expressed in the eyelid mesenchyme prior to and during eyelid fusion in a domain overlapping the expression of genes that also play a role in normal eyelid development. We show that Alx4 mutant mice have reduced expression of Fgf10, a key factor expressed in the mesenchyme that is required for initiation of eyelid fusion by the periderm. This is accompanied by a reduced number of periderm cells expressing phosphorylated c-Jun, consistent with the incomplete ablation of Fgf10 expression. Together, these data demonstrate that eyelid fusion in mice requires the expression of Alx4, accompanied by the loss of normal expression of essential components of the eyelid fusion pathway. PMID:25673119

  1. Mildly reduced graphene oxide-Ag nanoparticle hybrid films for surface-enhanced Raman scattering

    NASA Astrophysics Data System (ADS)

    Li, Xiaocheng; Tay, Beng Kang; Li, Junshuai; Tan, Dunlin; Tan, Chong Wei; Liang, Kun

    2012-04-01

    Large-area mildly reduced graphene oxide (MR-GO) monolayer films were self-assembled on SiO2/Si surfaces via an amidation reaction strategy. With the MR-GO as templates, MR-GO-Ag nanoparticle (MR-GO-Ag NP) hybrid films were synthesized by immersing the MR-GO monolayer into a silver salt solution with sodium citrate as a reducing agent under UV illumination. SEM image indicated that Ag NPs with small interparticle gap are uniformly distributed on the MR-GO monolayer. Raman spectra demonstrated that the MR-GO monolayer beneath the Ag NPs can effectively quench the fluorescence signal emitted from the Ag films and dye molecules under laser excitation, resulting in a chemical enhancement (CM). The Ag NPs with narrow gap provided numerous hot spots, which are closely related with electromagnetic mechanism (EM), and were believed to remarkably enhance the Raman signal of the molecules. Due to the co-contribution of the CM and EM effects as well as the coordination mechanism between the MR-GO and Ag NPs, the MR-GO-Ag NP hybrid films showed more excellent Raman signal enhancement performance than that of either Ag films or MR-GO monolayer alone. This will further enrich the application of surface-enhanced Raman scattering in molecule detection.

  2. Slotted surface coil with reduced g-factor for SENSE imaging.

    PubMed

    Ocegueda, K; Rodriguez, A O

    2006-01-01

    A new coil design inspired on the slot-and-hole magnetron tube is proposed for SENSE imaging. To investigate its g-factor behaviour: an SNR formula was derived using the quasi-static approach, and combined with the ultimate g-factor formula to compute the ultimate-factor-g-vs-depth plots. A g-factor expression was derived for the circular coil using the same approach for comparison purposes. SNR-vs-depth profiles of an 4-slot coil showed an important improvement over the circular coil. The 4-slot coil g-factor can be up to 58.32% lower than that of a single circular-shaped coil. This improvement makes the slotted surface coil a good choice for SENSE imaging. PMID:17946922

  3. Evaluating cell-surface expression and measuring activation of mammalian odorant receptors in heterologous cells

    PubMed Central

    Zhuang, Hanyi; Matsunami, Hiroaki

    2009-01-01

    A fundamental question in olfaction is which odorant receptors (ORs) are activated by a given odorant. A major roadblock to investigate odorant-OR relationship in mammals has been an inability to express ORs in heterologous cells suitable for screening active ligands for ORs. The discovery of the receptor-transporting protein (RTP) family has facilitated the effective cell-surface expression of ORs in heterologous cells. The establishment of a robust heterologous expression system for mammalian ORs facilitates the high-throughput “deorphanization” of these receptors by matching them to their cognate ligands. This protocol details the method used for evaluating the cell-surface expression and measuring the functional activation of ORs of transiently-expressed mammalian odorant receptors in HEK293T cells. The stages of odorant receptor cell-surface expression include cell culture preparation, transfer of cells, transfection, and immunocytochemistry/flow cytometry, odorant stimulation, and luciferase assay. This protocol can be completed in a period of 3 days from transfer of cells to cell-surface expression detection and/or measurement of functional activation. PMID:18772867

  4. A sensitive electrochemiluminescence cytosensor for quantitative evaluation of epidermal growth factor receptor expressed on cell surfaces.

    PubMed

    Tang, Yanjuan; Zhang, Shaolian; Wen, Qingqing; Huang, Hongxing; Yang, Peihui

    2015-06-30

    A sensitive electrochemiluminescence (ECL) strategy for evaluating the epidermal growth factor receptor (EGFR) expression level on cell surfaces was designed by integrating the specific recognition of EGFR expressed on MCF-7 cell surfaces with an epidermal growth factor (EGF)-funtionalized CdS quantum dots (CdSQDs)-capped magnetic bead (MB) probe. The high sensitivity of ECL probe of EGF-funtionalized CdSQD-capped-MB was used for competitive recognition with EGFR expressed on cell surfaces with recombinant EGFR protein. The changes of ECL intensity depended on both the cell number and the expression level of EGFR receptor on cell surfaces. A wide linear response to cells ranging from 80 to 4×10(6)cellsmL(-1) with a detection limit of 40cellsmL(-1) was obtained. The EGF-cytosensor was used to evaluate EGFR expression levels on MCF-7 cells, and the average number of EGFR receptor on single MCF-7 cells was 1.35×10(5) with the relative standard deviation of 4.3%. This strategy was further used for in-situ and real-time evaluating EGFR receptor expressed on cell surfaces in response to drugs stimulation at different concentration and incubation time. The proposed method provided potential applications in the detection of receptors on cancer cells and anticancer drugs screening. PMID:26041531

  5. Comparisons of soil surface sealing methods to reduce fumigant emission loss.

    PubMed

    Gao, Suduan; Hanson, Bradley D; Qin, Ruijun; Wang, Dong; Yates, Scott R

    2011-01-01

    State and federal regulatory agencies depend on quality field data for determining the effects of agricultural management practices on fumigant emissions to develop sound, science-based policies and regulations on preplant soil fumigants. Field plot tests, using growers' standard field operation procedures, were used to simultaneously determine the effectiveness of several commonly proposed emission reduction methods, in a trial involving shank injection of Telone II [a.i. 1,3-dichloropropnene (1,3-D)] to a sandy loam soil to a target rate of 372 kg ha(-1). The experiment was conducted in late September 2008 in the San Joaquin Valley of California. Fumigant emissions were captured using dynamic flux chambers. The results showed that virtually impermeable film (VIF) reduced emissions >95% when compared to bare soil, and the glue joints in the film did not significantly affect the tarp performance. The VIF also created a more uniform distribution of gaseous fumigant in the soil profile, which would likely benefit pest control efficacy. Standard high-density polyethylene (HDPE) tarp reduced total 1,3-D emissions about 50% (higher than most reported values) in this trial, whereas postfumigation intermittent water treatments (seals) reduced cumulative emission losses by approximately 20%. Adding 49.4 Mg ha (equivalent to 20 tons per acre) of composted dairy manure to surface soils did not reduce 1,3-D emissions during this experiment. Use of VIF was the most promising technique in reducing emissions and has the potential to allow lower application rates while providing satisfactory pest control. PMID:21869510

  6. Infection of vascular endothelial cells with herpes simplex virus enhances tissue factor activity and reduces thrombomodulin expression.

    PubMed Central

    Key, N S; Vercellotti, G M; Winkelmann, J C; Moldow, C F; Goodman, J L; Esmon, N L; Esmon, C T; Jacob, H S

    1990-01-01

    Latent infection of vascular cells with herpes-viruses may play a pathogenic role in the development of human atherosclerosis. In a previous study, we found that cultured human umbilical vein endothelial cells (HUVECs) infected with herpes simplex virus 1 (HSV-1) became procoagulant, exemplified both by their enhanced assembly of the prothrombinase complex and by their inability to reduce adhesion of platelets. We now report two further procoagulant consequences of endothelial HSV infection: loss of surface thrombomodulin (TM) activity and induction of synthesis of tissue factor. Within 4 hr of infection of HUVECs, TM activity measured by thrombin-dependent protein C activation declined 21 +/- 3% (P less than 0.05) and by 18 hr, 48 +/- 5% (P less than 0.001). Similar significant TM decrements accompanied infection of bovine aortic endothelial cells. Identical TM loss was induced with HSV-2 infection but not with adenovirus infection. Decreased surface expression of TM antigen (measured by the specific binding of a polyclonal antibody to bovine TM) closely paralleled the loss of TM activity. As examined by Northern blotting, these losses apparently reflected rapid onset (within 4 hr of HSV infection) loss of mRNA for TM. In contrast, HSV infection induced a viral-dose-dependent increase in synthesis of tissue factor protein, adding to the procoagulant state. The results indicate that loss of endothelial protein-synthetic capacity is not a universal effect of HSV infection. We suggest that the procoagulant state induced by reduction in TM activity and amplified tissue factor activity accompanying HSV infection of endothelium could contribute to deposition of thrombi on atherosclerotic plaques and to the "coagulant-necrosis" state that characterizes HSV-infected mucocutaneous lesions. Images PMID:2169619

  7. Surface expression of NMDA receptor changes during memory consolidation in the crab Neohelice granulata.

    PubMed

    Hepp, Yanil; Salles, Angeles; Carbo-Tano, Martin; Pedreira, Maria Eugenia; Freudenthal, Ramiro

    2016-08-01

    The aim of the present study was to analyze the surface expression of the NMDA-like receptors during the consolidation of contextual learning in the crab Neohelice granulata Memory storage is based on alterations in the strength of synaptic connections between neurons. The glutamatergic synapses undergo various forms of N-methyl-D aspartate receptor (NMDAR)-dependent changes in strength, a process that affects the abundance of other receptors at the synapse and underlies some forms of learning and memory. Here we propose a direct regulation of the NMDAR. Changes in NMDAR's functionality might be induced by the modification of the subunit's expression or cellular trafficking. This trafficking does not only include NMDAR's movement between synaptic and extra-synaptic localizations but also the cycling between intracellular compartments and the plasma membrane, a process called surface expression. Consolidation of contextual learning affects the surface expression of the receptor without affecting its general expression. The surface expression of the GluN1 subunit of the NMDAR is down-regulated immediately after training, up-regulated 3 h after training and returns to naïve and control levels 24 h after training. The changes in NMDAR surface expression observed in the central brain are not seen in the thoracic ganglion. A similar increment in surface expression of GluN1 in the central brain is observed 3 h after administration of the competitive GABAA receptor antagonist, bicuculline. These consolidation changes are part of a plasticity event that first, during the down-regulation, stabilizes the trace and later, at 3-h post-training, changes the threshold for synapse activation. PMID:27421895

  8. Tissue Plasminogen Activator Coating on Implant Surfaces Reduces Staphylococcus aureus Biofilm Formation

    PubMed Central

    Na, Manli; Jarneborn, Anders; Jacobsson, Gunnar; Peetermans, Marijke; Verhamme, Peter

    2015-01-01

    Staphylococcus aureus biofilm infections of indwelling medical devices are a major medical challenge because of their high prevalence and antibiotic resistance. As fibrin plays an important role in S. aureus biofilm formation, we hypothesize that coating of the implant surface with fibrinolytic agents can be used as a new method of antibiofilm prophylaxis. The effect of tissue plasminogen activator (tPA) coating on S. aureus biofilm formation was tested with in vitro microplate biofilm assays and an in vivo mouse model of biofilm infection. tPA coating efficiently inhibited biofilm formation by various S. aureus strains. The effect was dependent on plasminogen activation by tPA, leading to subsequent local fibrin cleavage. A tPA coating on implant surfaces prevented both early adhesion and later biomass accumulation. Furthermore, tPA coating increased the susceptibility of biofilm infections to antibiotics. In vivo, significantly fewer bacteria were detected on the surfaces of implants coated with tPA than on control implants from mice treated with cloxacillin. Fibrinolytic coatings (e.g., with tPA) reduce S. aureus biofilm formation both in vitro and in vivo, suggesting a novel way to prevent bacterial biofilm infections of indwelling medical devices. PMID:26519394

  9. Surface characteristics of coated polyester fabric with reduced graphene oxide and polypyrrole

    NASA Astrophysics Data System (ADS)

    Berendjchi, Amirhosein; Khajavi, Ramin; Yousefi, Ali Akbar; Yazdanshenas, Mohammad Esmail

    2016-03-01

    In this study, the influence of coating polyethylene terephthalate (PET) fabric with reduced graphene oxide (rGO) and polypyrrole (PPy), individually or in combination (rGO-PPy), on surface chemistry and roughness (focusing on wetting behavior), were analyzed systematically. Characterization was carried out by observing the topography (atomic force microscopy - AFM) and stating surface analysis (X-ray photoelectron spectroscopy - XPS), contact angles (goniometry), water shedding angles, and surface energy values of the samples. The results showed that the contact angles of pristine (uncoated), GO and rGO-PPy coated samples were 0°, while it was 92°, 123° and 151° for hot pressed (2nd pristine sample), rGO and PPy samples, respectively. A zero contact angle for PET sample was due to its wicking ability. Results were interpreted with Young, Wenzel and Cassie Baxter equations. It was found that PPy coated samples were consistent with Cassie-Baxter equation, while rGO placed between Wenzel and Cassie-Baxter wetting models.

  10. Rosiglitazone ameliorates diffuse axonal injury by reducing loss of tau and up-regulating caveolin-1 expression

    PubMed Central

    Zhao, Yong-lin; Song, Jin-ning; Ma, Xu-dong; Zhang, Bin-fei; Li, Dan-dong; Pang, Hong-gang

    2016-01-01

    Rosiglitazone up-regulates caveolin-1 levels and has neuroprotective effects in both chronic and acute brain injury. Therefore, we postulated that rosiglitazone may ameliorate diffuse axonal injury via its ability to up-regulate caveolin-1, inhibit expression of amyloid-beta precursor protein, and reduce the loss and abnormal phosphorylation of tau. In the present study, intraperitoneal injection of rosiglitazone significantly reduced the levels of amyloid-beta precursor protein and hyperphosphorylated tau (phosphorylated at Ser404(p-tau (S404)), and it increased the expression of total tau and caveolin-1 in the rat cortex. Our results show that rosiglitazone inhibits the expression of amyloid-beta precursor protein and lowers p-tau (S404) levels, and it reduces the loss of total tau, possibly by up-regulating caveolin-1. These actions of rosiglitazone may underlie its neuroprotective effects in the treatment of diffuse axonal injury. PMID:27482223

  11. Epothilone B Enhances Surface EpCAM Expression in Ovarian Cancer Hey Cells

    PubMed Central

    Shahabi, Shohreh; Yang, Chia-Ping Huang; Goldberg, Gary L.; Horwitz, Susan Band

    2010-01-01

    Objectives Epothilone B (EpoB), like Taxol, stabilizes microtubules resulting in an inhibition of microtubule dynamic instability. The drug is being evaluated in phase III clinical trials. An EpoB analog, Ixabepilone, was approved by the FDA for the treatment of taxane-resistant metastatic breast cancer. Epithelial cell adhesion antigen (EpCAM) expression is significantly higher in epithelial ovarian cancer cells compared to normal cells. The effects of EpoB and other microtubule-interacting agents on surface EpCAM expression were studied. Methods Biochemical methods, immunofluorescence and flow cytometry were used to identify EpCAM expression on the surface of the ovarian cancer cell line, Hey, after exposure to EpoB. The relationship between EpoB-mediated surface EpCAM expression and EpoB-induced α-tubulin acetylation, a surrogate marker for stable microtubules, in Hey cells also were investiaged. Results Nanomolar concentrations of EpoB, Taxol, discodermolide or vinblastine caused a marked increase in surface EpCAM expression in Hey cells. Alpha-tubulin acetylation was increased following treatment with Taxol, EpoB and discodermolide, but not with vinblastine, indicating that drug-enhanced surface EpCAM expression does not correlate with tubulin acetylation or stabilization. Unexpectedly, EpoB did not have a significant effect on EpCAM mRNA expression, nor did it alter the level of total cellular EpCAM in Hey cells. Conclusions The results indicate that disruption of the microtubule cytoskeleton is associated with the redistribution of cell surface antigens in ovarian cancer cells. The increase in cell surface EpCAM antigen density may facilitate the antibody targeting of EpCAM-positive ovarian cancer cells. PMID:20674962

  12. Postprandial dyslipidemia in men with visceral obesity: an effect of reduced LDL receptor expression?

    PubMed

    Mamo, J C; Watts, G F; Barrett, P H; Smith, D; James, A P; Pal, S

    2001-09-01

    Postprandial lipemia after an oral fat challenge was studied in middle-aged men with visceral obesity. The two groups had similar plasma cholesterol levels, but obese subjects had higher levels of plasma triglyceride and reduced amounts of high-density cholesterol. Fasting plasma insulin was fourfold greater in obese subjects because of concomitant insulin resistance, with a calculated HOMA score of 3.1 +/- 0.6 vs. 0.8 +/- 0.2, respectively. Plasma apolipoprotein B(48) (apoB(48)) and retinyl palmitate (RP) after an oral fat challenge were used to monitor chylomicron metabolism. Compared with lean subjects, the fasting concentration of apoB(48) was more than twofold greater in obese individuals, suggestive of an accumulation of posthydrolyzed particles. After the oral lipid load, the incremental areas under the apoB(48) and RP curves (IAUC) were both significantly greater in obese subjects (apoB(48): 97 +/- 17 vs. 44 +/- 12 microg.ml(-1). h; RP: 3,120 +/- 511 vs. 1,308 +/- 177 U. ml(-1). h, respectively). A delay in the conversion of chylomicrons to remnants probably contributed to postprandial dyslipidemia in viscerally obese subjects. The triglyceride IAUC was 68% greater in obese subjects (4.7 +/- 0.6 vs. 2.8 +/- 0.8 mM. h, P < 0.06). Moreover, peak postprandial triglyceride was delayed by approximately 2 h in obese subjects. The reduction in triglyceride lipolysis in vivo did not appear to reflect changes in hydrolytic enzyme activities. Postheparin plasma lipase rates were found to be similar for lean and obese subjects. In this study, low-density lipoprotein (LDL) receptor expression on monunuclear cells was used as a surrogate marker of hepatic activity. We found that, in obese subjects, the binding of LDL was reduced by one-half compared with lean controls (70.9 +/- 15.07 vs. 38.9 +/- 4.6 ng LDL bound/microg cell protein, P = 0.02). Because the LDL receptor is involved in the removal of proatherogenic chylomicron remnants, we suggest that the hepatic

  13. Modeling effectiveness of agricultural BMPs to reduce sediment load and organophosphate pesticides in surface runoff.

    PubMed

    Zhang, Xuyang; Zhang, Minghua

    2011-04-15

    Quantifying effectiveness of agricultural BMPs at the watershed scale is a challenging issue, requiring robust algorithms to simulate not only the agricultural production system but also pollutant transport and fate. This research addresses the challenge to simulate performances of BMPs in reducing organophosphates (OPs) runoff at the watershed scale. The SWAT model is calibrated and validated following a sensitivity analysis combining Latin Hypercube sampling and One-factor-At-a-Time simulation. The calibrated model is then applied in the Orestimba Creek Watershed to simulate BMPs including buffer strips, sediment ponds, vegetated ditches, use reduction, and their combinations. BMP simulation suggested that sediment ponds trap 54-85% of sediment from field runoff, but less than 10% of dissolved diazinon and chlorpyrifos. Use reduction can reduce pesticide load in a close-to-linear fashion. Effectiveness of vegetated ditches and buffers depends on their physical dimension and vegetation cover. Combining individual BMPs provides enhanced mitigation effects. The combination of vegetated ditches, buffer strips and use reduction decreases diazinon and chlorpyrifos load by over 94%. This study has suggested that the SWAT model reasonably predicts BMP effectiveness at the watershed scale. Results will assist decision making in implementing BMPs to reduce pesticide loads in surface runoff. PMID:21377192

  14. Microbial methanogenesis in the sulfate-reducing zone of surface sediments traversing the Peruvian margin

    NASA Astrophysics Data System (ADS)

    Maltby, J.; Sommer, S.; Dale, A. W.; Treude, T.

    2016-01-01

    We studied the concurrence of methanogenesis and sulfate reduction in surface sediments (0-25 cm below sea floor) at six stations (70, 145, 253, 407, 990 and 1024 m) along the Peruvian margin (12° S). This oceanographic region is characterized by high carbon export to the seafloor creating an extensive oxygen minimum zone (OMZ) on the shelf, both factors that could favor surface methanogenesis. Sediments sampled along the depth transect traversed areas of anoxic and oxic conditions in the bottom-near water. Net methane production (batch incubations) and sulfate reduction (35S-sulfate radiotracer incubation) were determined in the upper 0-25 cm b.s.f. of multiple cores from all stations, while deep hydrogenotrophic methanogenesis (> 30 cm b.s.f., 14C-bicarbonate radiotracer incubation) was determined in two gravity cores at selected sites (78 and 407 m). Furthermore, stimulation (methanol addition) and inhibition (molybdate addition) experiments were carried out to investigate the relationship between sulfate reduction and methanogenesis.

    Highest rates of methanogenesis and sulfate reduction in the surface sediments, integrated over 0-25 cm b.s.f., were observed on the shelf (70-253 m, 0.06-0.1 and 0.5-4.7 mmol m-2 d-1, respectively), while lowest rates were discovered at the deepest site (1024 m, 0.03 and 0.2 mmol m-2 d-1, respectively). The addition of methanol resulted in significantly higher surface methanogenesis activity, suggesting that the process was mostly based on non-competitive substrates - i.e., substrates not used by sulfate reducers. In the deeper sediment horizons, where competition was probably relieved due to the decrease of sulfate, the usage of competitive substrates was confirmed by the detection of hydrogenotrophic activity in the sulfate-depleted zone at the shallow shelf station (70 m).

    Surface methanogenesis appeared to be correlated to the availability of labile organic matter (C / N ratio) and organic carbon

  15. Microbial methanogenesis in the sulfate-reducing zone of surface sediments traversing the Peruvian margin

    NASA Astrophysics Data System (ADS)

    Maltby, J.; Sommer, S.; Dale, A. W.; Treude, T.

    2015-09-01

    We studied the concurrence of methanogenesis and sulfate reduction in surface sediments (0-25 cm below sea floor, cmbsf) at six stations (70, 145, 253, 407, 770 and 1024 m) along the Peruvian margin (12° S). This oceanographic region is characterized by high carbon export to the seafloor, creating an extensive oxygen minimum zone (OMZ) on the shelf, both factors that could favor surface methanogenesis. Sediments sampled along the depth transect traversed areas of anoxic and oxic conditions in the bottom-near water. Net methane production (batch incubations) and sulfate reduction (35S-sulfate radiotracer incubation) were determined in the upper 0-25 cmbsf of multicorer cores from all stations, while deep hydrogenotrophic methanogenesis (> 30 cmbsf, 14C-bicarbonate radiotracer incubation) was determined in two gravity cores at selected sites (78 and 407 m). Furthermore, stimulation (methanol addition) and inhibition (molybdate addition) experiments were carried out to investigate the relationship between sulfate reduction and methanogenesis. Highest rates of methanogenesis and sulfate reduction in the surface sediments, integrated over 0-25 cmbsf, were observed on the shelf (70-253 m, 0.06-0.1 and 0.5-4.7 mmol m-2 d-1, respectively), while lowest rates were discovered at the deepest site (1024 m, 0.03 and 0.2 mmol m-2 d-1, respectively). The addition of methanol resulted in significantly higher surface methanogenesis activity, suggesting that the process was mostly based on non-competitive substrates, i.e., substrates not used by sulfate reducers. In the deeper sediment horizons, where competition was probably relieved due to the decline of sulfate, the usage of competitive substrates was confirmed by the detection of hydrogenotrophic activity in the sulfate-depleted zone at the shallow shelf station (70 m). Surface methanogenesis appeared to be correlated to the availability of labile organic matter (C / N ratio) and organic carbon degradation (DIC production

  16. Searching for Reduced Carbon on the Surface of Mars: The SAM Combustion Experiment

    NASA Technical Reports Server (NTRS)

    Stern, J. C.; Malespin, C. A.; Mahaffy, P. R.; Webster, C. R.; Eigenbrode, J. L.; Archer, P. D., Jr.; Brunner, A. E.; Freissinet, C.; Franz, H. B.; Glavin, D. P.; Graham, H. V.; McAdam, A. C.; Ming, D. W.; Navarro-Gonzalez, R.; Niles, P. B.; Steele, A.; Sutter, B.; Trainer, M. G.

    2014-01-01

    The search for reduced carbon has been a major focus of past and present missions to Mars. Thermal evolved gas analysis was used by the Viking and Phoenix landers and is currently in use by the Sample Analysis at Mars (SAM) instrument suite on the Mars Science Laboratory (MSL) to characterize volatiles evolved from solid samples, including those associated with reduced organic species. SAM has the additional capability to perform a combustion experiment, in which a sample of Mars regolith is heated in the presence of oxygen and the composition of the evolved gases is measured using quadrupole mass spectrometry (QMS) and tunable laser spectrometry (TLS) [1]. Organics detection on the Martian surface has been complicated by oxidation and destruction during heating by soil oxidants [2], including oxychlorine compounds, and terrestrial organics in the SAM background contributed by one of the SAM wet chemistry reagents MTBSTFA (N-Methyl-N-tertbutyldimethylsilyl- trifluoroacetamide) [3,4]. Thermal Evolved Gas Analysis (TEGA) results from Phoenix show a mid temperature CO2 release between 400 C - 680 C speculated to be carbonate, CO2 adsorbed to grains, or combustion of organics by soil oxidants [5]. Low temperature CO2 evolutions (approx. 200 C - 400 C) were also present at all three sites in Gale Crater where SAM Evolved Gas Analysis (EGA) was performed, and potential sources include combustion of terrestrial organics from SAM, as well as combustion and/or decarboxylation either indigenous martian or exogenous organic carbon [4,6]. By performing an experiment to intentionally combust all reduced materials in the sample, we hope to compare the bulk abundance of CO2 and other oxidized species evolved by combustion to that evolved during an EGA experiment to estimate how much CO2 could be contributed by reduced carbon sources. In addition, C, O, and H isotopic compositions of CO2 and H2O measured by TLS can contribute information regarding the potential sources of these

  17. Cell surface expression and turnover of the alpha-subunit of the epithelial sodium channel.

    PubMed

    Kleyman, T R; Zuckerman, J B; Middleton, P; McNulty, K A; Hu, B; Su, X; An, B; Eaton, D C; Smith, P R

    2001-08-01

    The renal epithelial cell line A6, derived from Xenopus laevis, expresses epithelial Na(+) channels (ENaCs) and serves as a model system to study hormonal regulation and turnover of ENaCs. Our previous studies suggest that the alpha-subunit of Xenopus ENaC (alpha-xENaC) is detectable as 150- and 180-kDa polypeptides, putative immature and mature alpha-subunit heterodimers. The 150- and 180-kDa alpha-xENaC were present in distinct fractions after sedimentation of A6 cell lysate through a sucrose density gradient. Two anti-alpha-xENaC antibodies directed against distinct domains demonstrated that only 180-kDa alpha-xENaC was expressed at the apical cell surface. The half-life of cell surface-expressed alpha-xENaC was 24-30 h, suggesting that once ENaC matures and is expressed at the plasma membrane, its turnover is similar to that reported for mature cystic fibrosis transmembrane conductance regulator. No significant changes in apical surface expression of alpha-xENaC were observed after treatment of A6 cells with aldosterone for 24 h, despite a 5.3-fold increase in short-circuit current. This lack of change in surface expression is consistent with previous observations in A6 cells and suggests that aldosterone regulates ENaC gating and increases channel open probability. PMID:11457713

  18. Identification of genes affecting expression of phosphoglycerate kinase on the surface of group B streptococcus.

    PubMed

    Boone, Tyler J; Tyrrell, Gregory J

    2012-04-01

    Group B streptococcal phosphoglycerate kinase (GBS-PGK), a glycolytic enzyme, has previously been identified on the surface of group B streptococcus (GBS). To identify genes involved in surface expression of GBS-PGK, we performed Tn917 mutagenesis followed by quantification of PGK expressed on the GBS surface. Tn917 mutagenesis identified 4 genes (sag0966, sag0979, sag0980, and sag1003) that when disrupted, alter expression of GBS-PGK on the bacterial surface. Three of the identified genes were localized to a region of the GBS genome containing genes (sag0973-sag0977) predicted to be involved in resistance to antimicrobial peptides. One mutant isolate, designated NCS13sag1003::Tn917, was found to have increased sensitivity to the antimicrobial peptides bacitracin and nisin. In addition, all of the mutant strains assayed were found to have decreased β-hemolysis. In conclusion, we have identified genes involved in surface expression of GBS-PGK. These genes also appear to be involved in antimicrobial peptide resistance and regulate expression of the β-hemolysin. PMID:22444251

  19. Amyloid precursor protein enhances Nav1.6 sodium channel cell surface expression.

    PubMed

    Liu, Chao; Tan, Francis Chee Kuan; Xiao, Zhi-Cheng; Dawe, Gavin S

    2015-05-01

    Amyloid precursor protein (APP) is commonly associated with Alzheimer disease, but its physiological function remains unknown. Nav1.6 is a key determinant of neuronal excitability in vivo. Because mouse models of gain of function and loss of function of APP and Nav1.6 share some similar phenotypes, we hypothesized that APP might be a candidate molecule for sodium channel modulation. Here we report that APP colocalized and interacted with Nav1.6 in mouse cortical neurons. Knocking down APP decreased Nav1.6 sodium channel currents and cell surface expression. APP-induced increases in Nav1.6 cell surface expression were Go protein-dependent, enhanced by a constitutively active Go protein mutant, and blocked by a dominant negative Go protein mutant. APP also regulated JNK activity in a Go protein-dependent manner. JNK inhibition attenuated increases in cell surface expression of Nav1.6 sodium channels induced by overexpression of APP. JNK, in turn, phosphorylated APP. Nav1.6 sodium channel surface expression was increased by T668E and decreased by T668A, mutations of APP695 mimicking and preventing Thr-668 phosphorylation, respectively. Phosphorylation of APP695 at Thr-668 enhanced its interaction with Nav1.6. Therefore, we show that APP enhances Nav1.6 sodium channel cell surface expression through a Go-coupled JNK pathway. PMID:25767117

  20. The prognostic role and reduced expression of FOXJ2 in human hepatocellular carcinoma

    PubMed Central

    ZHANG, ZHONGBAO; MENG, GUANGJU; WANG, LIANG; MA, YINGYING; GUAN, ZHONGZHENG

    2016-01-01

    The current study aimed to investigate the potential role of the FOXJ2 (forkhead box J2) protein in the pathology of hepatocellular carcinoma (HCC). Western blotting was performed to determine the expression levels of FOXJ2 in HCC tissues and HCC cells. Specimens from 110 patients with HCC undergoing hepatic resection were evaluated for FOXJ2 expression using an immunohistochemical assay. The correlation between FOXJ2 expression and clinicopathological factors of the patients was determined by statistical analysis to determine the prognostic merit of FOXJ2 expression in HCC. The detailed involvement of FOXJ2 in the regulation of HCC proliferation was further investigated using FOXJ2-targeting small interfering RNA (siRNA). FOXJ2 protein was identified to be significantly downregulated in HCC tissues compared with adjacent normal liver tissues. Immunohistochemical analysis demonstrated that the expression of FOXJ2 was negatively correlated with Ki-67 levels in HCC specimens (r=−0.679, P<0.001). Furthermore, statistical analysis indicated FOXJ2 expression was significantly associated with histological differentiation (P=0.005), the size of largest tumor (P=0.002) and metastasis (P=0.036). Using Kaplan-Meier analysis, it was demonstrated that high FOXJ2 expression levels predicted significantly improved patient survival rates compared with low FOXJ2 expression levels (P<0.001). In addition, it was observed that interference of FOXJ2 expression using siRNA oligos led to the promotion of proliferation of HepG2 cells. FOXJ2 was markedly downregulated in HCC tissues. The expression of FOXJ2 was correlated with tumor size, histological differentiation and metastasis. Low expression levels of FOXJ2 predicted poor prognosis for patients with HCC, suggesting that FOXJ2 may be a candidate prognostic marker of HCC. Depletion of FOXJ2 caused the promotion of HCC cell proliferation, implicating that FOXJ2 may serve an inhibitory role in the regulation of HCC cell proliferation

  1. Supercapacitors based on highly dispersed polypyrrole-reduced graphene oxide composite with a folded surface

    NASA Astrophysics Data System (ADS)

    Wang, Anqi; Zhou, Xi; Qian, Tao; Yu, Chenfei; Wu, Shishan; Shen, Jian

    2015-08-01

    Highly dispersed polypyrrole particles were decorated on reduced graphene oxide sheets using a facile in situ synthesis route. The prepared composite, which obtained a folded surface, shows remarkable performance as the electrode material of supercapacitors. The specific capacitance reaches 564.1 F g-1 at a current density of 1 A g-1 and maintains 86.4 % after 1000 charging-discharging cycles at a current density of 20 A g-1, which indicates a good cycling stability. Furthermore, the prepared supercapacitor demonstrates an ultrahigh energy density of 50.13 Wh kg-1 at power density of 0.40 kW kg-1, and remains of 45.33 Wh kg-1 even at high power density of 8.00 kW kg-1, which demonstrate that the hybrid supercapacitor can be a promising energy storage system for fast and efficient energy storage in the future.

  2. Reducing Escherichia coli growth on a composite biomaterial by a surface immobilized antimicrobial peptide.

    PubMed

    Buckholtz, Gavin A; Reger, Nina A; Anderton, William D; Schimoler, Patrick J; Roudebush, Shana L; Meng, Wilson S; Miller, Mark C; Gawalt, Ellen S

    2016-08-01

    A new composite bioceramic consisting of calcium aluminum oxide (CaAlO) and hydroxyapatite (HA) was functionalized with the synthetic antimicrobial peptide Inverso-CysHHC10. CaAlO is a bioceramic that can be mold cast easily and quickly at room temperature. Improved functionality was previously achieved through surface reactions. Here, composites containing 0-5% HA (by mass) were prepared and the elastic modulus and modulus of rupture were mechanically similar to non-load bearing bone. The addition of hydroxyapatite resulted in increased osteoblast attachment (>180%) and proliferation (>140%) on all composites compared to 100% CaAlO. Antimicrobial peptide (AMP) immobilization was achieved using an interfacial alkene-thiol click reaction. The linked AMP persisted on the composite (>99.6% after 24h) and retained its activity against Escherichia coli based on N-phenylnaphthylamine uptake and bacterial turbidity tests. Overall, this simple scaffold system improves osteoblast activity and reduces bacterial activity. PMID:27157735

  3. Fluorogenic Green-Inside Red-Outside (GIRO) Labeling Approach Reveals Adenylyl Cyclase-Dependent Control of BKα Surface Expression

    PubMed Central

    2015-01-01

    The regulation of surface levels of protein is critical for proper cell function and influences properties including cell adhesion, ion channel contributions to current flux, and the sensitivity of surface receptors to ligands. Here we demonstrate a two-color labeling system in live cells using a single fluorogen activating peptide (FAP) based fusion tag, which enables the rapid and simultaneous quantification of surface and internal proteins. In the nervous system, BK channels can regulate neural excitability and neurotransmitter release, and the surface trafficking of BK channels can be modulated by signaling cascades and assembly with accessory proteins. Using this labeling approach, we examine the dynamics of BK channel surface expression in HEK293 cells. Surface pools of the pore-forming BKα subunit were stable, exhibiting a plasma membrane half-life of >10 h. Long-term activation of adenylyl cyclase by forskolin reduced BKα surface levels by 30%, an effect that could not be attributed to increased bulk endocytosis of plasma membrane proteins. This labeling approach is compatible with microscopic imaging and flow cytometry, providing a solid platform for examining protein trafficking in living cells. PMID:26301573

  4. Evaluating the Performance of a Surface Barrier on Reducing Soil-Water Flow

    SciTech Connect

    Zhang, Z. F.; Strickland, Christopher E.; Field, Jim G.; Parker, Danny L.; Clayton, Ray E.

    2012-08-31

    One of the most common effective techniques for contaminant remediation in the vadose zone is to use a surface barrier to reduce or eliminate soil-water flow to reduce the contaminant flux to the underlying groundwater. Confirming the reduction of the soil-water flux rate is challenging because of the difficulty of determining the very low soil-water flux beneath the barrier. We propose a hydraulic-conductivity factor, fK, as a conservative indicator for quantifying the reduction of soil-water flow. The factor can be calculated using the measured soil-water content or pressure but does not require the knowledge of the saturated hydraulic conductivity or the hydraulic gradient. The formulas were tested by comparing with changes in hydraulic conductivity, K, from a drainage experiment. The pressure-based formula was further applied to evaluate the performance of the interim surface barrier at T Tank Farm on Hanford Site. Three years after barrier emplacement, the hydraulic conductivity decreased by a factor between 3.8 and 13.0 at the 1-, 2- and 5-m depths. The difference between the conductivity-reduction factor and the flux-rate-reduction factor, fq, was quantified with a numerical simulation. With the calculated fK, the numerically determined fK/fq ratio, and the assumed pre-barrier soil-water flux rate of 100 mm yr-1, the estimated soil-water flux rate 3 years after barrier emplacement was no more than 8.5 mm yr-1 at or above the 5-m depth.

  5. The Hedgehog Inhibitor Cyclopamine Reduces β-Catenin-Tcf Transcriptional Activity, Induces E-Cadherin Expression, and Reduces Invasion in Colorectal Cancer Cells.

    PubMed

    Qualtrough, David; Rees, Phil; Speight, Beverley; Williams, Ann C; Paraskeva, Christos

    2015-01-01

    Colorectal cancer is a major global health problem resulting in over 600,000 deaths world-wide every year with the majority of these due to metastatic disease. Wnt signalling, and more specifically β-catenin-related transcription, has been shown to drive both tumorigenesis and the metastatic process in colorectal neoplasia, yet its complex interactions with other key signalling pathways, such as hedgehog, remain to be elucidated. We have previously shown that the Hedgehog (HH) signalling pathway is active in cells from colorectal tumours, and that inhibition of the pathway with cyclopamine induces apoptosis. We now show that cyclopamine treatment reduces β-catenin related transcription in colorectal cancer cell lines, and that this effect can be reversed by addition of Sonic Hedgehog protein. We also show that cyclopamine concomitantly induces expression of the tumour suppressor and prognostic indicator E-cadherin. Consistent with a role for HH in regulating the invasive potential we show that cyclopamine reduces the expression of transcription factors (Slug, Snail and Twist) associated with the epithelial-mesenchymal transition and reduces the invasiveness of colorectal cancer cells in vitro. Taken together, Cancers 2015, 7 1886 these data show that pharmacological inhibition of the hedgehog pathway has therapeutic potential in the treatment of colorectal cancer. PMID:26393651

  6. Cell-surface serglycin promotes adhesion of myeloma cells to collagen type I and affects the expression of matrix metalloproteinases.

    PubMed

    Skliris, Antonis; Labropoulou, Vassiliki T; Papachristou, Dionysios J; Aletras, Alexios; Karamanos, Nikos K; Theocharis, Achilleas D

    2013-05-01

    Serglycin (SG) is mainly expressed by hematopoetic cells as an intracellular proteoglycan. Multiple myeloma cells constitutively secrete SG, which is also localized on the cell surface in some cell lines. In this study, SG isolated from myeloma cells was found to interact with collagen type I (Col I), which is a major bone matrix component. Notably, myeloma cells positive for cell-surface SG (csSG) adhered significantly to Col I, compared to cells lacking csSG. Removal of csSG by treatment of the cells with chondroitinase ABC or blocking of csSG by an SG-specific polyclonal antibody significantly reduced the adhesion of myeloma cells to Col I. Significant up-regulation of expression of the matrix metalloproteinases MMP-2 and MMP-9 at both the mRNA and protein levels was observed when culturing csSG-positive myeloma cells on Col I-coated dishes or in the presence of soluble Col I. MMP-9 and MMP-2 were also expressed in increased amounts by myeloma cells in the bone marrow of patients with multiple myeloma. Our data indicate that csSG of myeloma cells affects key functional properties, such as adhesion to Col I and the expression of MMPs, and imply that csSG may serve as a potential prognostic factor and/or target for pharmacological interventions in multiple myeloma. PMID:23387827

  7. Specific Inhibition of Histone Deacetylase 8 Reduces Gene Expression and Production of Proinflammatory Cytokines in Vitro and in Vivo*

    PubMed Central

    Li, Suzhao; Fossati, Gianluca; Marchetti, Carlo; Modena, Daniela; Pozzi, Pietro; Reznikov, Leonid L.; Moras, Maria Luisa; Azam, Tania; Abbate, Antonio; Mascagni, Paolo; Dinarello, Charles A.

    2015-01-01

    ITF2357 (generic givinostat) is an orally active, hydroxamic-containing histone deacetylase (HDAC) inhibitor with broad anti-inflammatory properties, which has been used to treat children with systemic juvenile idiopathic arthritis. ITF2357 inhibits both Class I and II HDACs and reduces caspase-1 activity in human peripheral blood mononuclear cells and the secretion of IL-1β and other cytokines at 25–100 nm; at concentrations >200 nm, ITF2357 is toxic in vitro. ITF3056, an analog of ITF2357, inhibits only HDAC8 (IC50 of 285 nm). Here we compared the production of IL-1β, IL-1α, TNFα, and IL-6 by ITF2357 with that of ITF3056 in peripheral blood mononuclear cells stimulated with lipopolysaccharide (LPS), heat-killed Candida albicans, or anti-CD3/anti-CD28 antibodies. ITF3056 reduced LPS-induced cytokines from 100 to 1000 nm; at 1000 nm, the secretion of IL-1β was reduced by 76%, secretion of TNFα was reduced by 88%, and secretion of IL-6 was reduced by 61%. The intracellular levels of IL-1α were 30% lower. There was no evidence of cell toxicity at ITF3056 concentrations of 100–1000 nm. Gene expression of TNFα was markedly reduced (80%), whereas IL-6 gene expression was 40% lower. Although anti-CD3/28 and Candida stimulation of IL-1β and TNFα was modestly reduced, IFNγ production was 75% lower. Mechanistically, ITF3056 reduced the secretion of processed IL-1β independent of inhibition of caspase-1 activity; however, synthesis of the IL-1β precursor was reduced by 40% without significant decrease in IL-1β mRNA levels. In mice, ITF3056 reduced LPS-induced serum TNFα by 85% and reduced IL-1β by 88%. These data suggest that specific inhibition of HDAC8 results in reduced inflammation without cell toxicity. PMID:25451941

  8. Dehydroepiandrosterone 7-hydroxylase CYP7B: predominant expression in primate hippocampus and reduced expression in Alzheimer's disease.

    PubMed

    Yau, J L W; Rasmuson, S; Andrew, R; Graham, M; Noble, J; Olsson, T; Fuchs, E; Lathe, R; Seckl, J R

    2003-01-01

    Neurosteroids such as dehydroepiandrosterone (DHEA), pregnenolone and 17beta-estradiol are synthesized by cytochrome P450s from endogenous cholesterol. We previously reported a new cytochrome P450 enzyme, CYP7B, highly expressed in rat and mouse brain that metabolizes DHEA and related steroids by hydroxylation at the 7alpha position. Such 7-hydroxylation can enhance DHEA bioactivity in vivo. Here we show that the reaction is conserved across mammalian species: in addition to mouse and rat, DHEA hydroxylation activity was present in brain extracts from sheep, marmoset and human. Northern blotting using a human CYP7B complementary deoxyribonucleic acid (cDNA) probe confirmed the presence of CYP7B mRNA in marmoset and human hippocampus; CYP7B mRNA was present in marmoset cerebellum and brainstem, with lower levels in hypothalamus and cortex. In situ hybridization to human brain revealed higher levels of CYP7B mRNA in the hippocampus than in cerebellum, cortex, or other brain regions. We also measured CYP7B expression in Alzheimer's disease (AD). CYP7B mRNA was significantly decreased (approximately 50% decline; P<0.05) in dentate neurons from AD subjects compared with controls. A decline in CYP7B activity may contribute the loss of effects of DHEA with ageing and perhaps to the pathophysiology of AD. PMID:14521990

  9. High-surface-area nitrogen-doped reduced graphene oxide for electric double-layer capacitors

    DOE PAGESBeta

    Youn, Hee-Chang; Bak, Seong-Min; Kim, Myeong-Seong; Jaye, Cherno; Fischer, Daniel A.; Lee, Chang-Wook; Yang, Xiao-Qing; Roh, Kwang Chul; Kim, Kwang-Bum

    2015-06-08

    A two-step method consisting of solid-state microwave irradiation and heat treatment under NH₃ gas was used to prepare nitrogen-doped reduced graphene oxide (N-RGO) with a high specific surface area (1007m²g⁻¹), high electrical conductivity (1532S m⁻¹), and low oxygen content (1.5 wt%) for electric double-layer capacitor applications. The specific capacitance of N-RGO was 291 Fg⁻¹ at a current density of 1 A g⁻¹, and a capacitance of 261 F g⁻¹ was retained at 50 A g⁻¹, indicating a very good rate capability. N-RGO also showed excellent cycling stability, preserving 96% of the initial specific capacitance after 100,000 cycles. Near-edge X-ray absorptionmore » fine-structure spectroscopy evidenced the recover of π-conjugation in the carbon networks with the removal of oxygenated groups and revealed the chemical bonding of the nitrogen atoms in N-RGO. The good electrochemical performance of N-RGO is attributed to its high surface area, high electrical conductivity, and low oxygen content.« less

  10. High-Surface-Area Nitrogen-Doped Reduced Graphene Oxide for Electric Double-Layer Capacitors.

    PubMed

    Youn, Hee-Chang; Bak, Seong-Min; Kim, Myeong-Seong; Jaye, Cherno; Fischer, Daniel A; Lee, Chang-Wook; Yang, Xiao-Qing; Roh, Kwang Chul; Kim, Kwang-Bum

    2015-06-01

    A two-step method consisting of solid-state microwave irradiation and heat treatment under NH3 gas was used to prepare nitrogen-doped reduced graphene oxide (N-RGO) with a high specific surface area (1007 m(2)  g(-1) ), high electrical conductivity (1532 S m(-1) ), and low oxygen content (1.5 wt %) for electrical double-layer capacitor applications. The specific capacitance of N-RGO was 291 F g(-1) at a current density of 1 A g(-1) , and a capacitance of 261 F g(-1) was retained at 50 A g(-1) , which indicated a very good rate capability. N-RGO also showed excellent cycling stability and preserved 96 % of the initial specific capacitance after 100 000 cycles. Near-edge X-ray absorption fine-structure spectroscopy results provided evidenced for the recovery of π conjugation in the carbon networks with the removal of oxygenated groups and revealed chemical bonding of the nitrogen atoms in N-RGO. The good electrochemical performance of N-RGO is attributed to its high surface area, high electrical conductivity, and low oxygen content. PMID:25916491

  11. High-surface-area nitrogen-doped reduced graphene oxide for electric double-layer capacitors

    SciTech Connect

    Youn, Hee-Chang; Bak, Seong-Min; Kim, Myeong-Seong; Jaye, Cherno; Fischer, Daniel A.; Lee, Chang-Wook; Yang, Xiao-Qing; Roh, Kwang Chul; Kim, Kwang-Bum

    2015-06-08

    A two-step method consisting of solid-state microwave irradiation and heat treatment under NH₃ gas was used to prepare nitrogen-doped reduced graphene oxide (N-RGO) with a high specific surface area (1007m²g⁻¹), high electrical conductivity (1532S m⁻¹), and low oxygen content (1.5 wt%) for electric double-layer capacitor applications. The specific capacitance of N-RGO was 291 Fg⁻¹ at a current density of 1 A g⁻¹, and a capacitance of 261 F g⁻¹ was retained at 50 A g⁻¹, indicating a very good rate capability. N-RGO also showed excellent cycling stability, preserving 96% of the initial specific capacitance after 100,000 cycles. Near-edge X-ray absorption fine-structure spectroscopy evidenced the recover of π-conjugation in the carbon networks with the removal of oxygenated groups and revealed the chemical bonding of the nitrogen atoms in N-RGO. The good electrochemical performance of N-RGO is attributed to its high surface area, high electrical conductivity, and low oxygen content.

  12. Tyrosine phosphorylation regulates the endocytosis and surface expression of GluN3A-containing NMDA receptors.

    PubMed

    Chowdhury, Dhrubajyoti; Marco, Sonia; Brooks, Ian M; Zandueta, Aitor; Rao, Yijian; Haucke, Volker; Wesseling, John F; Tavalin, Steven J; Pérez-Otaño, Isabel

    2013-02-27

    Selective control of receptor trafficking provides a mechanism for remodeling the receptor composition of excitatory synapses, and thus supports synaptic transmission, plasticity, and development. GluN3A (formerly NR3A) is a nonconventional member of the NMDA receptor (NMDAR) subunit family, which endows NMDAR channels with low calcium permeability and reduced magnesium sensitivity compared with NMDARs comprising only GluN1 and GluN2 subunits. Because of these special properties, GluN3A subunits act as a molecular brake to limit the plasticity and maturation of excitatory synapses, pointing toward GluN3A removal as a critical step in the development of neuronal circuitry. However, the molecular signals mediating GluN3A endocytic removal remain unclear. Here we define a novel endocytic motif (YWL), which is located within the cytoplasmic C-terminal tail of GluN3A and mediates its binding to the clathrin adaptor AP2. Alanine mutations within the GluN3A endocytic motif inhibited clathrin-dependent internalization and led to accumulation of GluN3A-containing NMDARs at the cell surface, whereas mimicking phosphorylation of the tyrosine residue promoted internalization and reduced cell-surface expression as shown by immunocytochemical and electrophysiological approaches in recombinant systems and rat neurons in primary culture. We further demonstrate that the tyrosine residue is phosphorylated by Src family kinases, and that Src-activation limits surface GluN3A expression in neurons. Together, our results identify a new molecular signal for GluN3A internalization that couples the functional surface expression of GluN3A-containing receptors to the phosphorylation state of GluN3A subunits, and provides a molecular framework for the regulation of NMDAR subunit composition with implications for synaptic plasticity and neurodevelopment. PMID:23447623

  13. Reduced E-cadherin expression as a cause of distinctive signet-ring cell variant in colorectal carcinoma.

    PubMed Central

    Kim, Hee Cheol; Kim, Ho Jeong; Kim, Jin Cheon

    2002-01-01

    Colorectal signet-ring cell carcinoma (SRCC) is a rare type of adenocarcinoma and presents with distinctive clinicopathological features. This study was performed to assess the biological characteristics of colorectal SRCC regarding the E-cadherin expression. Seventeen patients with primary colorectal SRCC were identified and their clinicopathological characteristics were analyzed. The mean age of the 17 patients was 45.3 yr (14-68). Immunohistochemical staining of E-cadherin and beta-catenin were performed in ten colorectal SRCCs and in 30 ordinary colorectal adenocarcinomas as control. Primary colorectal SRCC occurred in 0.7% of 2,388 colorectal adenocarcinomas. Most patients had advanced stage tumor at surgery (stage III and IV, AJCC: 82%). Five-year survival rate was 16%. Peritoneal seeding was the most common recurrence pattern (41%) and liver metastasis was not identified. All SRCCs showed a markedly reduced or absent expression of E-cadherin on immunohistochemical staining, whereas seven (23.3%) of ordinary carcinomas showed reduced expression, thereby indicating a significant difference between the two groups (p<0.005). In immunohistochemical staining for beta-catenin, eight of ten SRCCs showed reduced membrane expression that did not attain statistical significance compared to ordinary adenocarcinomas. It is suggested that aberrant E-cadherin expression may explain the distinct clinicopathological features in primary colorectal SRCC. PMID:11850584

  14. Mutation of a transcriptional motif of a distant regulatory element reduces the expression of embryonic and fetal globin genes

    PubMed Central

    Navas, Patrick A.; Swank, Richard A.; Yu, Man; Peterson, Kenneth R.; Stamatoyannopoulos, George

    2010-01-01

    High-level β-globin gene expression is dependent on the presence of the locus control region (LCR), a powerful regulatory element physically characterized by five DNase I-hypersensitive sites (HS), designated HS1–HS5. Of these, HS3 contains seven GT motifs that are essential for its activity. One of the motifs, GT6, has been shown by in vivo footprinting to display the largest difference in signal between fetal and adult globin expressing cells. We assessed the contribution of GT6 on the downstream globin gene expression by mutating this motif in a 248 kb β-globin locus yeast artificial chromosome and measuring the activity of β-globin genes in GT6m β-YAC transgenic mice. Seven transgenic lines were established, three of which contained at least one intact copy of the β-globin locus and were further investigated. The mutation of the GT6 motif reduced the expression of ε- and γ-globin genes during embryonic erythropoiesis. During definitive erythropoiesis, γ-globin gene expression was significantly reduced while β-globin gene expression was virtually indistinguishable from wild-type controls. We conclude that the GT6 motif of hypersensitive site 3 of the LCR is required for normal ε- and γ-globin gene expression during embryonic erythropoiesis and for γ-globin gene expression during definitive erythropoiesis in the fetal liver. Our results provide evidence that mutations of single transcriptional motifs of distant regulatory elements can have profound effects on gene expression. PMID:14506128

  15. Reversing the reduced level of endometrial GLUT4 expression in polycystic ovary syndrome: a mechanistic study of metformin action

    PubMed Central

    Li, Xin; Cui, Peng; Jiang, Hong-Yuan; Guo, Yan-Rong; Pishdari, Bano; Hu, Min; Feng, Yi; Billig, Håkan; Shao, Ruijin

    2015-01-01

    Conflicting results have been reported regarding whether or not insulin-regulated glucose transporter 4 (GLUT4) is expressed in human and rodent endometria. There is an inverse relationship between androgen levels and insulin-dependent glucose metabolism in women. Hyperandrogenemia, hyperinsulinemia, and insulin resistance are believed to contribute to endometrial abnormalities in women with polycystic ovary syndrome (PCOS). However, it has been unclear in previous studies if endometrial GLUT4 expression is regulated by androgen-dependent androgen receptors (ARs) and/or the insulin receptor/Akt/mTOR signaling network. In this study, we demonstrate that GLUT4 is expressed in normal endometrial cells (mainly in the epithelial cells) and is down-regulated under conditions of hyperandrogenemia in tissues from PCOS patients and in a 5α-dihydrotestosterone-induced PCOS-like rat model. Western blot analysis revealed reduced endometrial GLUT4 expression and increased AR expression in PCOS patients. However, the reduced GLUT4 level was not always associated with an increase in AR in PCOS patients when comparing non-hyperplasia with hyperplasia. Using a human tissue culture system, we investigated the molecular basis by which GLUT4 regulation in endometrial hyperplasia tissues is affected by metformin in PCOS patients. We show that specific endogenous organic cation transporter isoforms are regulated by metformin, and this suggests a direct effect of metformin on endometrial hyperplasia. Moreover, we demonstrate that metformin induces GLUT4 expression and inhibits AR expression and blocks insulin receptor/PI3K/Akt/mTOR signaling in the same hyperplasia human tissues. These findings indicate that changes in endometrial GLUT4 expression in PCOS patients involve the androgen-dependent alteration of AR expression and changes in the insulin receptor/PI3K/Akt/mTOR signaling network. PMID:26045896

  16. Reversing the reduced level of endometrial GLUT4 expression in polycystic ovary syndrome: a mechanistic study of metformin action.

    PubMed

    Li, Xin; Cui, Peng; Jiang, Hong-Yuan; Guo, Yan-Rong; Pishdari, Bano; Hu, Min; Feng, Yi; Billig, Håkan; Shao, Ruijin

    2015-01-01

    Conflicting results have been reported regarding whether or not insulin-regulated glucose transporter 4 (GLUT4) is expressed in human and rodent endometria. There is an inverse relationship between androgen levels and insulin-dependent glucose metabolism in women. Hyperandrogenemia, hyperinsulinemia, and insulin resistance are believed to contribute to endometrial abnormalities in women with polycystic ovary syndrome (PCOS). However, it has been unclear in previous studies if endometrial GLUT4 expression is regulated by androgen-dependent androgen receptors (ARs) and/or the insulin receptor/Akt/mTOR signaling network. In this study, we demonstrate that GLUT4 is expressed in normal endometrial cells (mainly in the epithelial cells) and is down-regulated under conditions of hyperandrogenemia in tissues from PCOS patients and in a 5α-dihydrotestosterone-induced PCOS-like rat model. Western blot analysis revealed reduced endometrial GLUT4 expression and increased AR expression in PCOS patients. However, the reduced GLUT4 level was not always associated with an increase in AR in PCOS patients when comparing non-hyperplasia with hyperplasia. Using a human tissue culture system, we investigated the molecular basis by which GLUT4 regulation in endometrial hyperplasia tissues is affected by metformin in PCOS patients. We show that specific endogenous organic cation transporter isoforms are regulated by metformin, and this suggests a direct effect of metformin on endometrial hyperplasia. Moreover, we demonstrate that metformin induces GLUT4 expression and inhibits AR expression and blocks insulin receptor/PI3K/Akt/mTOR signaling in the same hyperplasia human tissues. These findings indicate that changes in endometrial GLUT4 expression in PCOS patients involve the androgen-dependent alteration of AR expression and changes in the insulin receptor/PI3K/Akt/mTOR signaling network. PMID:26045896

  17. Multi-resistive Reduced Graphene Oxide Diode with Reversible Surface Electrochemical Reaction induced Carrier Control

    PubMed Central

    Seo, Hyungtak; Ahn, Seungbae; Kim, Jinseo; Lee, Young-Ahn; Chung, Koo-Hyun; Jeon, Ki-Joon

    2014-01-01

    The extended application of graphene-based electronic devices requires a bandgap opening in order to realize the targeted device functionality. Since the bandgap tuning of pristine graphene is limited to 360 meV, the chemical modification of graphene is considered essential to achieve a large bandgap opening at the expense of electrical properties degradation. Reduced graphene oxide (RGO) has attracted significant interest for fabricating graphene-based semiconductors since it has several advantages over other forms of chemically modified graphene; such as tunable bandgap opening, decent electrical properties, and easy synthesis. Because of the reduced bonding nature of RGO, the role of metastable oxygen in the RGO matrix is recently highlighted and it may offer emerging ionic devices. In this study, we show that multi-resistivity RGO/n-Si diodes can be obtained by controlling the RGO thickness at a nanometer scale. This is made possible by (1) a metastable lattice-oxygen drift within bulk RGO and (2) electrochemical ambient hydroxyl (OH) formation at the RGO surface. The effect demonstrated in a p-RGO/n-Si heterojunction diode is equivalent to electrochemically driven reversible electronic manipulation and therefore provides an important basis for the application of O bistability in RGO for chemical sensors and electrocatalysis. PMID:25007942

  18. Surface irrigation reduces the emission of volatile 1,3-dichloropropene from agricultural soils.

    PubMed

    Ashworth, D J; Yates, S R

    2007-04-01

    Low-cost, practicable techniques are required to limit the release of volatile organic compound-containing fumigants such as 1,3-D to the atmosphere. In this study, we aimed to quantify 1,3-D diffusion and emission from laboratory soil columns maintained under realistic conditions and thereby assess the efficacy of soil irrigation as a technique for reducing emissions. In two soils (one relatively high, and one relatively low, in organic matter), irrigation led to a limiting of upward diffusion of the fumigant and to the maintenance of higher soil gas concentrations. Therefore, rather than being emitted from the column, the 1,3-D was maintained in the soil where it was ultimately degraded. As a consequence, emission of 1,3-D from the irrigated columns was around half of thatfrom the nonirrigated columns. It is concluded that surface irrigation represents an effective, low-cost, and readily practicable approach to lessening the environmental impact of 1,3-D fumigant use. In addition, the higher organic matter soil exhibited emissions of around one-fifth of the lower organic matter soil in both irrigated and nonirrigated treatments, due to markedly enhanced degradation of the fumigant. Organic matter amendment of soils may, therefore, also represent an extremely effective, relatively low-cost approach to reducing 1,3-D emissions. PMID:17438768

  19. Using breast cancer cell CXCR4 surface expression to predict liposome binding and cytotoxicity.

    PubMed

    Guo, Peng; You, Jin-Oh; Yang, Jiang; Moses, Marsha A; Auguste, Debra T

    2012-11-01

    The primary cause of mortality in breast cancer is tumor aggressiveness, characterized by metastases to regional lymph nodes, bone marrow, lung, and liver. C-X-C chemokine receptor type 4 (CXCR4) has been shown to mobilize breast cancer cells along chemokine gradients. Quantification of CXCR4 surface expression may predict the efficacy of anti-CXCR4 labeled liposomal therapeutics to target and kill breast cancer cells. We evaluated gene and surface receptor expression of CXCR4 on breast cancer cell lines distinguished as having low and high invasiveness, MDA-MB-175VII and HCC1500, respectively. CXCR4 surface expression did not correlate with invasiveness. MDA-MB-175VII exhibited more binding to anti-CXCR4 labeled liposomes relative to HCC1500. Increased binding correlated with greater cell death relative to IgG labeled liposomes. Quantitative cell characterization may be used to select targeted therapeutics with enhanced efficacy and minimal side effects. PMID:22884683

  20. PHTHALATE ESTER-INDUCED GUBERNACULAR LESIONS ARE ASSOCIATED WITH REDUCED INSL-3 GENE EXPRESSION IN THE FETAL RAT TESTIS

    EPA Science Inventory

    Phthalate ester-induced gubernacular ligament lesions are associated with reduced Insl3 gene expression in the fetal rat testis during sexual differentiation.
    VS Wilson, C Lambright, J Furr, J Ostby, C Wood, G Held, LE Gray Jr.
    U.S. EPA, ORD, NHEERL, Reproductive Toxicology...

  1. 1,25-Dihydroxyvitamin D3 Reduces Extracellular Matrix-Associated Protein Expression in Human Uterine Fibroid Cells1

    PubMed Central

    Halder, Sunil K.; Osteen, Kevin G.; Al-Hendy, Ayman

    2013-01-01

    ABSTRACT Uterine fibroids (leiomyomas) are the most common benign tumors associated with excessive deposition of extracellular matrix (ECM)-associated proteins that increase fibroid tumorigenicity. Herein, we determined the expression levels of vitamin D receptor (VDR) protein in human uterine fibroids and compared these levels to those in adjacent normal myometrium. Using Western blot analysis, we found that more than 60% of uterine fibroids analyzed (25 of 40) expressed low levels of VDR. We also found that the biologically active 1,25-dihydroxyvitamin D3 (1,25[OH]2D3), which functions via binding to its nuclear VDR, induced VDR in a concentration-dependent manner and reduced ECM-associated fibrotic and proteoglycans expression in immortalized human uterine fibroid cell line (HuLM). At 1–10 nM concentrations, 1,25(OH)2D3 significantly induced (P < 0.05) nuclear VDR, which was further stimulated by higher concentrations of 1,25(OH)2D3 in HuLM cells. 1,25(OH)2D3 at 10 nM also significantly reduced (P < 0.05) the protein expression of ECM-associated collagen type 1, fibronectin, and plasminogen activator inhibitor-1 (PAI-1) in HuLM cells. We also found that 1,25(OH)2D3 reduced mRNA and protein expressions of proteoglycans such as fibromodulin, biglycan, and versican in HuLM cells. Moreover, the aberrant expression of structural smooth muscle actin fibers was reduced by 1,25(OH)2D3 treatment in a concentration-dependent manner in HuLM cells. Taken together, our results suggest that human uterine fibroids express reduced levels of VDR compared to the adjacent normal myometrium and that treatment with 1,25(OH)2D3 can potentially reduce the aberrant expression of major ECM-associated proteins in HuLM cells. Thus, 1,25(OH)2D3 might be an effective, safe, nonsurgical treatment option for human uterine fibroids. PMID:24174578

  2. Reducing surface water total and methyl mercury concentrations and bioavailability using a coagulation-wetland system

    NASA Astrophysics Data System (ADS)

    Kraus, T. E.; Fleck, J.; Henneberry, Y. K.; Stumpner, E. B.; Krabbenhoft, D. P.; Bachand, P.; Randall, P.

    2013-12-01

    With the recent passage of laws regulating concentrations and loads of mercury (Hg) in surface waters, there is a need to develop management practices that will reduce the export of Hg from both point and non-point sources. Coagulation with metal based salts to remove particles and dissolved organic matter (DOM) from solution is a practice commonly employed by drinking water utilities. Because dissolved Hg is associated with particles and DOM, it follows that Hg should also be removed during the coagulation process and end up associated with the organo-metal precipitate, termed flocculate (floc). The effectiveness of iron- and aluminum-based coagulants for removing both inorganic and methyl mercury (IHg and MeHg, respectively) from solution was demonstrated in laboratory studies conducted on agricultural drainage waters of the Sacramento-San Joaquin Delta: dissolved concentrations of MeHg decreased by 80% while IHg decreased by 97% following coagulation. To test the field application of this technology, samples were collected from the inflows and outflows of wetland treatment cells constructed in the central Delta of California. This replicated field experiment includes three replicates each of three inflow waters treatments: (1) iron sulfate addition, (2) polyaluminum chloride addition, and (3) untreated controls. Water entering and exiting the nine treatment cells was sampled approximately monthly over a 1-year period for total Hg and MeHg in both the dissolved and particulate aqueous phases. Initial results confirm that coagulant addition is removing Hg (total and methyl, particulate and dissolved) from solution and sequestering it in the floc. Seasonal effects on DOM concentration and other factors appear to effect whether passage through the wetland cells alters surface water dissolved organic carbon (DOC) and Hg concentrations. Related studies will examine whether the presence of the floc affects the production and fate of MeHg within the wetland cells. If

  3. Hypoxia reduces constitutive and TNF-{alpha}-induced expression of monocyte chemoattractant protein-1 in human proximal renal tubular cells

    SciTech Connect

    Li Xuan; Kimura, Hideki . E-mail: hkimura@fmsrsa.fukui-med.ac.jp; Hirota, Kiichi; Sugimoto, Hidehiro; Yoshida, Haruyoshi

    2005-10-07

    Chronic hypoxia has been reported to be associated with macrophage infiltration in progressive forms of kidney disease. Here, we investigated the regulatory effects of hypoxia on constitutive and TNF-{alpha}-stimulated expression of monocyte chemoattractant protein-1 (MCP-1) in cultured human proximal renal tubular cells (HPTECs). Hypoxia reduced constitutive MCP-1 expression at the mRNA and protein levels in a time-dependent fashion for up to 48 h. Hypoxia also inhibited MCP-1 up-regulation by TNF-{alpha}. Treatment with actinomycin D showed that hypoxic down-regulation of MCP-1 expression resulted mainly from a decrease in the transcription but not the mRNA stability. Immunoblot and immunofluorescence analyses revealed that treatment with hypoxia or an iron chelator, desferrioxamine, induced nuclear accumulation of hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) in HPTECs. Desferrioxamine mimicked hypoxia in the reduction of MCP-1 expression. However, overexpression of a dominant negative form of HIF-1{alpha} did not abolish the hypoxia-induced reduction of MCP-1 expression in HPTECs. These results suggest that hypoxia is an important negative regulator of monocyte chemotaxis to the renal inflamed interstitium, by reducing MCP-1 expression partly via hypoxia-activated signals other than the HIF-1 pathway.

  4. Enkephalins stimulate leukemia cell migration and surface expression of CD9.

    PubMed Central

    Heagy, W; Duca, K; Finberg, R W

    1995-01-01

    Opioid peptides have been implicated in the regulation of tumor growth and biology; however, little attention has been given to the mechanisms that are involved. In this study we show that physiological concentrations of the endogenous opioid neuropeptide methionine-enkephalin (MET-ENK) and the synthetic enkephalins D-Ala2, Me-Phe4, Gly(ol)5 and D-Ala2, D-Leu5 are stimulants for the in vitro migration of pre-B acute lymphoblastoid leukemia (ALL) cells. Activation of the human pre-B ALL cell lines NALM 6 and LAZ 221 with MET-ENK resulted in both an increase in their migration and an augmentation in the surface expression of the leukemia cell marker CD9. The opiate receptor antagonist naloxone reversed these enkephalin-induced effects on the leukemia cells. When the pre-B ALL cells were preincubated with an anti-CD9 mAb before challenge with MET-ENK their migration to the enkephalin was markedly reduced. These studies show that endogenous and synthetic opioid peptides are stimulants for pre-B ALL cell migration and suggest that CD9 is important in the regulation of leukemia cell motility. Images PMID:7657811

  5. Tn5 insertion mutants of Pseudomonas aeruginosa deficient in surface expression of ferripyochelin-binding protein

    SciTech Connect

    Sokol, P.A.

    1987-07-01

    Transposon (Tn5) insertion mutants were isolated in Pseudomonas aeruginosa PAO. These mutants were screened for expression of the ferripyochelin-binding protein with monoclonal antibody in a whole-cell immunoblot assay. Fourteen mutants were identified which did not express ferripyochelin-binding protein on the cell surface. These mutants did not take up /sup 59/Fe-labeled pyochelin and grew slowly in the presence of iron chelators.

  6. Increased matrix metalloproteinase-2 expression and reduced tissue factor pathway inhibitor-2 expression correlate with angiogenesis and early postoperative recurrence of pancreatic carcinoma

    PubMed Central

    Zhai, Lu-Lu; Wu, Yang; Huang, Da-Wei; Tang, Zhi-Gang

    2015-01-01

    Matrix metalloproteinase (MMP)-2 and tissue factor pathway inhibitor (TFPI)-2 are known to influence tumor angiogenesis and progression. This work aimed to describe the levels of MMP-2 and TFPI-2 expression associated with tumor angiogenesis and early postoperative recurrence in patients with pancreatic carcinoma. Expression of MMP-2 and TFPI-2 in carcinoma tissues and paracarcinomatous tissues was assayed by immunostaining. Expression of vascular endothelial growth factor (VEGF) and CD34 in tumor tissues was also assayed by immunostaining. The correlations of MMP-2 and TFPI-2 with VEGF, microvessel density (MVD), and early postoperative recurrence were analyzed. The results showed that MMP-2 expression was significantly increased (P < 0.05) and TFPI-2 expression was significantly decreased (P < 0.001) in carcinoma tissues compared with paracarcinomatous tissues. MMP-2 expression was positively correlated with VEGF (r = 0.594, P < 0.001) and MVD (r = 0.432, P < 0.001) in carcinoma tissues. TFPI-2 expression was negatively correlated with VEGF (r = -0.654, P < 0.001) and MVD (r = -0.360, P < 0.001) in carcinoma tissues. Multivariate logistic regression analysis showed that up-regulated MMP-2 and down-regulated TFPI-2 were independent predictors of early postoperative recurrence of pancreatic carcinoma. Receiver operating characteristic curve analysis showed that the combination of MMP-2 and TFPI-2 was a reliable predictive model of early recurrence. We conclude that increased MMP-2 expression and reduced TFPI-2 expression are closely linked to angiogenesis and early postoperative recurrence of pancreatic carcinoma. Immunohistochemical assay of MMP-2 and TFPI-2 may be useful for predicting early relapse of pancreatic carcinoma after surgery. PMID:26807187

  7. Cell surface expression of LDL receptor in chronic hepatitis C: correlation with viral load.

    PubMed

    Petit, Jean-Michel; Minello, Anne; Duvillard, Laurence; Jooste, Valérie; Monier, Serge; Texier, Véronique; Bour, Jean-Baptiste; Poussier, Alix; Gambert, Philippe; Verges, Bruno; Hillon, Patrick

    2007-07-01

    The LDL receptor (LDL-R) has been proposed as the viral receptor for Hepatitis C virus (HCV). This hypothesis has been based exclusively on in vitro studies. In human mononuclear cells, LDL-R gene expression has been demonstrated to be parallel and be coordinately regulated to gene expression in the human liver. The purpose of the current study was to determine the mononuclear cell surface expression of the LDL receptor in patients with HCV chronic infection according to viral load. Sixty-eight consecutive untreated chronic hepatitis C patients were studied to determine the mononuclear cell surface expression of the LDL-R. LDL-Rs were quantified at the surface of mononuclear cells in fresh blood samples taken after fasting using flow cytometry. LDL-R expression was significantly associated with LDL-cholesterol (r = -0.25; P = 0.03) and HCV-viral load (r = 0.37, P = 0.002). In multivariate analysis, the LDL-R expression was significantly associated with HCV viral load, whereas genotype, age, body mass index, and fibrosis were not. In conclusion, our data provided by a human study, suggest that the LDL-R may be one of the receptors implicated in HCV replication. PMID:17473053

  8. Reduced catabolic protein expression in Clostridium butyricum DSM 10702 correlate with reduced 1,3-propanediol synthesis at high glycerol loading

    PubMed Central

    2014-01-01

    Higher initial glycerol loadings (620 mM) have a negative effect on growth and 1,3-propanediol (1,3-PDO) synthesis in Clostridium butyricum DSM 10702 relative to lower initial glycerol concentrations (170 mM). To help understand metabolic shifts associated with elevated glycerol, protein expression levels were quantified by LC/MS/MS analyses. Thirty one (31) proteins involved in conversion of glycerol to 1,3-PDO and other by-products were analyzed by multiple reaction monitoring (MRM). The analyses revealed that high glycerol concentrations reduced cell growth. The expression levels of most proteins in glycerol catabolism pathways were down-regulated, consistent with the slower growth rates observed. However, at high initial glycerol concentrations, some of the proteins involved in the butyrate synthesis pathways such as a putative ethanol dehydrogenase (CBY_3753) and a 3-hydroxybutyryl-CoA dehydrogenase (CBY_3045) were up-regulated in both exponential and stationary growth phases. Expression levels of proteins (CBY_0500, CBY_0501 and CBY_0502) involved in the reductive pathway of glycerol to 1,3-PDO were consistent with glycerol consumption and product concentrations observed during fermentation at both glycerol concentrations, and the molar yields of 1,3-PDO were similar in both cultures. This is the first report that correlates expression levels of glycerol catabolism enzymes with synthesis of 1,3-PDO in C. butyricum. The results revealed that significant differences in the expression of a small subset of proteins were observed between exponential and stationary growth phases at both low and high glycerol concentrations. PMID:25401066

  9. Delphinidin prevents disuse muscle atrophy and reduces stress-related gene expression.

    PubMed

    Murata, Motoki; Kosaka, Reia; Kurihara, Kana; Yamashita, Shuya; Tachibana, Hirofumi

    2016-08-01

    Delphinidin is a member of the anthocyanidin class of plant pigments. We examined the effects of delphinidin on muscle atrophy. Oral administration of delphinidin suppressed the muscle weight loss induced by mechanical unloading. Microarray analysis showed that delphinidin suppresses the upregulation of oxidative stress-related gene expression, including the expression of Cbl-b. Thus, delphinidin may prevent unloading-mediated muscle atrophy. PMID:27180787

  10. Weight-loss changes PPAR expression, reduces atherosclerosis and improves cardiovascular function in obese insulin-resistant mice

    SciTech Connect

    Verreth, Wim; Verhamme, Peter; Pelat, Michael; Ganame, Javier; Bielicki, John K.; Mertens, Ann; Quarck, Rozenn; Benhabiles, Nora; Marguerie, Gerard; Mackness, Bharti; Mackness, Mike; Ninio, Ewa; Herregods, Marie-Christine; Balligand, Jean-Luc; Holvoet, Paul

    2003-09-01

    Weight-loss in obese insulin-resistant, but not in insulin-sensitive, persons reduces CHD risk. It is not known to what extent changes in the adipose gene expression profile are important for reducing CHD risk. We studied the effect of diet restriction-induced weight-loss on gene expression in adipose tissue, atherosclerosis and cardiovascular function in mice with combined leptin and LDL-receptor deficiency. Obesity, hypertriglyceridemia and insulin-resistance are associated with hypertension, impaired left ventricle function and accelerated atherosclerosis in those mice. Diet restriction during 12 weeks caused a 45% weight-loss and changes in the gene expression in adipose tissue of PPARa and PPAR? and of key genes regulating glucose transport and insulin sensitivity, lipid metabolism, oxidative stress and inflammation, most of which are under the transcriptional control of PPARs. These changes were associated with increased insulin-sensitivity, decreased hypertriglyceridemia, reduced mean 24-hour blood pressure and heart rate, restored circadian variations of blood pressure and heart rate, increased ejection fraction, and reduced atherosclerosis. Thus, induction of PPARa and PPAR? in adipose tissue is a key mechanism for reducing atherosclerosis and improving cardiovascular function resulting from weight-loss. Our observations point to the critical role of PPARs in the pathogenesis of cardiovascular features of the metabolic syndrome.

  11. Estimation of Land Surface Energy Balance Using Satellite Data of Spatial Reduced Resolution

    NASA Astrophysics Data System (ADS)

    Vintila, Ruxandra; Radnea, Cristina; Savin, Elena; Poenaru, Violeta

    2010-12-01

    The paper presents preliminary results concerning the monitoring at national level of several geo-biophysical variables retrieved by remote sensing, in particular those related to drought or aridisation. The study, which is in progress, represents also an exercise for to the implementation of a Land Monitoring Core Service for Romania, according to the Kopernikus Program and in compliance with the INSPIRE Directive. The SEBS model has been used to retrieve land surface energy balance variables, such as turbulent heat fluxes, evaporative fraction and daily evaporation, based on three information types: (1) surface albedo, emissivity, temperature, fraction of vegetation cover (fCover), leaf area index (LAI) and vegetation height; (2) air pressure, temperature, humidity and wind speed at the planetary boundary layer (PBL) height; (3) downward solar radiation and downward longwave radiation. AATSR and MERIS archived reprocessed images have provided several types of information. Thus, surface albedo, emissivity, and land surface temperature have been retrieved from AATSR, while LAI and fCover have been estimated from MERIS. The vegetation height has been derived from CORINE Land Cover and PELCOM Land Use databases, while the meteorological information at the height of PBL have been estimated from the measurements provided by the national weather station network. Other sources of data used during this study have been the GETASSE30 digital elevation model with 30" spatial resolution, used for satellite image orthorectification, and the SIGSTAR-200 geographical information system of soil resources of Romania, used for water deficit characterisation. The study will continue by processing other AATSR and MERIS archived images, complemented by the validation of SEBS results with ground data collected on the most important biomes for Romania at various phenological stages, and the transformation of evaporation / evapotranspiration into a drought index using the soil texture

  12. Mass spectrometry analysis of surface tension reducing substances produced by a pah-degrading Pseudomonas citronellolis strain

    PubMed Central

    Jacques, Rodrigo J. S.; Santos, Eder C.; Haddad, Renato; Catharino, Rodrigo R.; Eberlin, Marcos N.; Bento, Fátima M.; de Oliveira Camargo, Flávio A.

    2008-01-01

    In this work we investigated the structure of the iron-stimulated surface tension reducing substances produced by P. citronellolis 222A isolated from a 17-years old landfarming used for sludge treatment in petrochemical industries and oil refinery. Its mass spectrum differs from P. aeruginosa spectrum, indicating that the surface tension reducing substances produced by P. citronellolis can be a new kind of biosurfactant. PMID:24031229

  13. Maternal High-Fat Feeding Increases Placental Lipoprotein Lipase Activity by Reducing SIRT1 Expression in Mice.

    PubMed

    Qiao, Liping; Guo, Zhuyu; Bosco, Chris; Guidotti, Stefano; Wang, Yunfeng; Wang, Mingyong; Parast, Mana; Schaack, Jerome; Hay, William W; Moore, Thomas R; Shao, Jianhua

    2015-09-01

    This study investigated how maternal overnutrition and obesity regulate expression and activation of proteins that facilitate lipid transport in the placenta. To create a maternal overnutrition and obesity model, primiparous C57BL/6 mice were fed a high-fat (HF) diet throughout gestation. Fetuses from HF-fed dams had significantly increased serum levels of free fatty acid and body fat. Despite no significant difference in placental weight, lipoprotein lipase (LPL) protein levels and activity were remarkably elevated in placentas from HF-fed dams. Increased triglyceride content and mRNA levels of CD36, VLDLr, FABP3, FABPpm, and GPAT2 and -3 were also found in placentas from HF-fed dams. Although both peroxisome proliferator-activated receptor-γ (PPARγ) and CCAAT/enhancer binding protein-α protein levels were significantly increased in placentas of the HF group, only PPARγ exhibited a stimulative effect on LPL expression in cultured JEG-3 human trophoblasts. Maternal HF feeding remarkably decreased SIRT1 expression in placentas. Through use of an SIRT1 activator and inhibitor and cultured trophoblasts, an inhibitory effect of SIRT1 on LPL expression was demonstrated. We also found that SIRT1 suppresses PPARγ expression in trophoblasts. Most importantly, inhibition of PPARγ abolished the SIRT1-mediated regulatory effect on LPL expression. Together, these results indicate that maternal overnutrition induces LPL expression in trophoblasts by reducing the inhibitory effect of SIRT1 on PPARγ. PMID:25948680

  14. MicroRNA-142 Reduces Monoamine Oxidase A Expression and Activity in Neuronal Cells by Downregulating SIRT1

    PubMed Central

    Datta Chaudhuri, Amrita; Yelamanchili, Sowmya V.; Fox, Howard S.

    2013-01-01

    Aberrant expression of microRNAs (miRs) has been implicated in the pathogenesis of several neurodegenerative disorders. In HIV-associated neurocognitive disorders (HAND), miR-142 was found to be upregulated in neurons and myeloid cells in the brain. We investigated the downstream effects of chronic miR-142 upregulation in neuronal cells by comparing gene expression in stable clones of the human neuroblastoma cell line BE(2)M17 expressing miR-142 to controls. Microarray analysis revealed that miR-142 expression led to a reduction in monoamine oxidase (MAO) A mRNA, which was validated by qRT-PCR. In addition to the mRNA, the MAOA protein level and enzyme activity were also reduced. Examination of primary human neurons revealed that miR-142 expression indeed resulted in a downregulation of MAOA protein level. Although MAOA is not a direct target of miR-142, SIRT1, a key transcriptional upregulator of MAOA is, thus miR-142 downregulation of MAOA expression is indirect. MiR-142 induced decrease in MAOA expression and activity may contribute to the changes in dopaminergic neurotransmission reported in HAND. PMID:24244526

  15. Analytical evaluation of a surface integral expressing the coupling between interior and exterior volumes in a FE-IE approach

    NASA Technical Reports Server (NTRS)

    Zuffada, C.; Cwik, T.; Jamnejad, V.

    1993-01-01

    Recently an approach which combines the finite element technique and an integral equation to determine the fields scattered by inhomogeneous bodies of complicated shape has been proposed. Basically, a mathematical surface which encloses the scatterers is introduced, thus dividing the space into an interior and an exterior volume, in which the finite element technique and an integral equation for EM scattering, respectively, are applied. The integral equation is set up for the tangential components of the fields at the surface, while the interior volume the unknowns are the total fields. Continuity of the tangential fields at the boundary, as required by Maxwell's equations, is imposed, thus coupling the two methods to obtain a consistent solution. The coupling term is expressed by a surface integral formed by the dot product of a FE basis function and an IE testing function, or viceversa. By choosing the boundary to be a surface of revolution and by making a convenient selection of IE basis (testing) functions, it is possible to evaluate the integrals analytically on surfaces such as curved triangles, curved quadrilaterals and curved pentagons. We will illustrate the salient steps involved in setting up and carrying out these integrals and discuss what class of basis (testing) functions and analytic surfaces of revolution they are applicable to. Analytic calculations offer the advantage of better accuracy than purely numerical ones, and, when combined with them, often shed light on issues of numerical convergence and limiting values. Furthermore, they may reduce computation time and storage requirements.

  16. Reduced miRNA-218 expression in pancreatic cancer patients as a predictor of poor prognosis.

    PubMed

    Li, B-S; Liu, H; Yang, W-L

    2015-01-01

    microRNA-218 (miR-218) is a vertebrate-specific miRNA that plays a crucial role in tumorigenesis and tumor progression. This study analyzed the miR-218 expression level and clinical significance in pancreatic cancer. One hundred and seven pairs of pancreatic cancer and adjacent normal tissues were analyzed by quantitative reverse-transcriptase polymerase chain reaction. The correlation between miR-218 expression and clinicopathological characters was determined by the two-sample Student t-test. The survival correlations were analyzed by the Kaplan-Meier method and Cox proportional hazards model. The relative expression of miR-218 in pancreatic cancer tissues (2.63 ± 1.59) was significantly lower than that in matched noncancerous pancreatic tissues (6.52 ± 2.50, P < 0.001). The low expression of miR-218 in the pancreatic cancer tissues were strongly correlated with the TNM classification (P = 0.02), distant metastasis (P = 0.001), and tumor differentiation (P = 0.003). The low level of miR-218 expression was significantly correlated with the shorter overall survival time of pancreatic cancer patients (5-year overall survival rate: 7.5 vs 34.9%; log-rank test: P < 0.001). Multivariate analyses confirmed that a low level of miR-218 expression was an independent predictor of poor prognosis in pancreatic cancer patients (Hazard ratio: 7.24; 95% confidence interval: 2.01-18.28; P = 0.007). Our findings suggested a significant downregulation in the expression of miR-218; this might have considerable potential value in the prognosis for pancreatic cancer. PMID:26662432

  17. Corneal Expression of SLURP-1 by Age, Sex, Genetic Strain, and Ocular Surface Health

    PubMed Central

    Swamynathan, Sudha; Delp, Emili E.; Harvey, Stephen A. K.; Loughner, Chelsea L.; Raju, Leela; Swamynathan, Shivalingappa K.

    2015-01-01

    Purpose Although secreted Ly6/urokinase-type plasminogen activator receptor–related protein-1 (Slurp1) transcript is highly abundant in the mouse cornea, corresponding protein expression remains uncharacterized. Also, SLURP1 was undetected in previous tear proteomics studies, resulting in ambiguity about its baseline levels. Here, we examine mouse corneal Slurp1 expression in different sexes, age groups, strains, and health conditions, and quantify SLURP1 in human tears from healthy or inflamed ocular surfaces. Methods Expression of Slurp1 in embryonic day-13 (E13), E16, postnatal day-1 (PN1), PN10, PN20, and PN70 Balb/C, FVBN, C57Bl/6, and DBA/2J mouse corneas, Klf4Δ/ΔCE corneas with corneal epithelial–specific ablation of Klf4, migrating cells in wild-type corneal epithelial wound edge, and in corneas exposed to pathogen-associated molecular patterns (PAMPs) poly(I:C), zymosan-A, or Pam3Csk4 was examined by QPCR, immunoblots, and immunofluorescent staining. Human SLURP1 levels were quantified by ELISA in tears from 34 men and women aged 18 to 80 years. Results Expression of Slurp1, comparable in different strains and sexes, was low in E13, E16, PN1, and PN10 mouse corneas, and increased rapidly after eyelid opening in a Klf4-dependent manner. We found Slurp1 was downregulated in corneas exposed to PAMPs, and in migrating cells at the wound edge. Human SLURP1 expression, comparable in different sexes and age groups, was significantly decreased in tears from inflamed ocular surfaces (0.34%) than those from healthy individuals (0.77%). Conclusions These data describe the influence of age, sex, genetic background, and ocular surface health on mouse corneal expression of Slurp1, establish the baseline for human tear SLURP1 expression, and identify SLURP1 as a useful diagnostic and/or therapeutic target for inflammatory ocular surface disorders. PMID:26670825

  18. Reduced Expression of α-Synuclein in Alcoholic Brain: Influence of SNCA-Rep1 Genotype

    PubMed Central

    Janeczek, Paulina; MacKay, Rachel K.; Lea, Rodney A.; Dodd, Peter R.; Lewohl, Joanne M.

    2012-01-01

    α-Synuclein has recently been implicated in the pathophysiology of alcohol abuse due to its role in dopaminergic neurotransmission. In these studies, genetic variability in the α-synuclein gene influences its expression which may contribute to susceptibility to chronic alcohol abuse. Real-time PCR was used to quantify α-synuclein mRNA expression in autopsy samples of human dorsolateral prefrontal cortex. Because of the association between length of the α-synuclein-repeat 1 microsatellite marker and expression levels of the gene, this marker was genotyped in a Caucasian sample of 126 controls and 117 alcoholics using capillary gel electrophoresis. The allele and genotype frequencies of α-synuclein-repeat 1 marker differed significantly between alcoholics and controls. Alcoholics had greater frequencies of the shortest allele found (267 bp). The shortest allele of the α-synuclein-repeat 1 marker was associated with decreased expression of α-synuclein in prefrontal cortex. Individuals with at least one copy of the 267 bp allele were more likely to exhibit an alcohol abuse phenotype. These results suggest that individuals with the 267 bp allele may be at increased risk of developing alcoholism and that genetic variation at the α-synuclein-repeat 1 locus may influence α-synuclein expression in the prefrontal cortex. PMID:22974310

  19. Reduced expression of exocytotic proteins caused by anti-cholinesterase pesticides in Brachionus calyciflorus (Rotifera: Monogononta).

    PubMed

    Pérez-Legaspi, I A; Rico-Martínez, R; Quintanar, J L

    2015-08-01

    The organophosphate and carbamate pesticides methyl-parathion and carbaryl have a common action mechanism: they inhibit acetylcholinesterase enzyme by blocking the transmission of nerve impulses. However, they can alter the expression of exocytotic membrane proteins (SNARE), by modifying release of neurotransmitters and other substances. This study evaluated the adverse effects of the pesticides methyl-parathion and carbaryl on expression of SNARE proteins: Syntaxin-1, Syntaxin-4 and SNAP-23 in freshwater rotifer Brachionus calyciflorus. Protein expression of these three proteins was analyzed before and after exposure to these two pesticides by Western Blot. The expression of Syntaxin-1, Syntaxin-4 and SNAP-23 proteins in B. calyciflorussignificantly decreases with increasing concentration of either pesticides. This suggests that organophosphates and carbamates have adverse effects on expression of membrane proteins of exocytosis by altering the recognition, docking and fusion of presynaptic and vesicular membranes involved in exocytosis of neurotransmitters. Our results demonstrate that the neurotoxic effect of anticholinesterase pesticides influences the interaction of syntaxins and SNAP-25 and the proper assembly of the SNARE complex. PMID:26465735

  20. Reduced Susceptibility to Xanthomonas citri in Transgenic Citrus Expressing the FLS2 Receptor From Nicotiana benthamiana.

    PubMed

    Hao, Guixia; Pitino, Marco; Duan, Yongping; Stover, Ed

    2016-02-01

    Overexpression of plant pattern-recognition receptors by genetic engineering provides a novel approach to enhance plant immunity and broad-spectrum disease resistance. Citrus canker disease associated with Xanthomonas citri is one of the most important diseases damaging citrus production worldwide. In this study, we cloned the FLS2 gene from Nicotiana benthamiana cDNA and inserted it into the binary vector pBinPlus/ARS to transform Hamlin sweet orange and Carrizo citrange. Transgene presence was confirmed by polymerase chain reaction (PCR) and gene expression of NbFLS2 was compared by reverse transcription quantitative PCR. Reactive oxygen species (ROS) production in response to flg22Xcc was detected in transgenic Hamlin but not in nontransformed controls. Low or no ROS production was detected from nontransformed Hamlin seedlings challenged with flg22Xcc. Transgenic plants highly expressing NbFLS2 were selected and were evaluated for resistance to canker incited by X. citri 3213. Our results showed that the integration and expression of the NbFLS2 gene in citrus can increase canker resistance and defense-associated gene expression when challenged with X. citri. These results suggest that canker-susceptible Citrus genotypes lack strong basal defense induced by X. citri flagellin and the resistance of these genotypes can be enhanced by transgenic expression of the flagellin receptor from a resistant species. PMID:26554734

  1. Investigation of chemical rinses suitable for very small meat plants to reduce pathogens on beef surfaces.

    PubMed

    Yoder, Sally F; Henning, William R; Mills, Edward W; Doores, Stephanie; Ostiguy, Nancy; Cutter, Catherine N

    2012-01-01

    Numerous antimicrobial interventions are capable of reducing the prevalence of harmful bacteria on raw meat products. There is a need to identify effective and inexpensive antimicrobial interventions that could, in practice, be used in very small meat plants because of limited financial, space, and labor resources. Eight antimicrobial compounds (acetic acid, citric acid, lactic acid, peroxyacetic acid, acidified sodium chlorite, chlorine dioxide, sodium hypochlorite, and aqueous ozone) were applied at various concentrations with small, hand-held spraying equipment, and bactericidal effectiveness was examined. Beef plate pieces were inoculated with fecal slurry containing a pathogen cocktail (Escherichia coli O157:H7, Salmonella Typhimurium, Campylobacter coli, and Campylobacter jejuni) and natural populations of aerobic plate counts, coliforms, and E. coli. Antimicrobial solutions were applied to beef surfaces via a portable, pressurized hand-held spray tank, and treated surfaces were subjected to appropriate methods for the enumeration and isolation of pathogens and hygiene indicators. Relative antimicrobial effectiveness was determined (from greatest to least): (i) organic acids, (ii) peroxyacetic acid, (iii) chlorinated compounds, and (iv) aqueous ozone. Using the equipment described, a 2% lactic acid rinse provided 3.5- to 6.4-log CFU/cm(2) reductions across all bacterial populations studied. Conversely, aqueous ozone yielded 0.02- to 2.9-log CFU/cm(2) reductions in pathogens and hygiene indicators, and did not differ significantly from a control tap water rinse (P = 0.055 to 0.731). This 2% lactic acid rinse will be subsequently combined with a previously described water wash to create a multistep antimicrobial intervention that will be examined under laboratory conditions and validated in very small meat plants. PMID:22221350

  2. Reducing saturated fatty acids in Arabidopsis seeds by expression of a Caenorhabditis elegans 16:0-specific desaturase.

    PubMed

    Fahy, Deirdre; Scheer, Barbara; Wallis, James G; Browse, John

    2013-05-01

    Plant oilseeds are a major source of nutritional oils. Their fatty acid composition, especially the proportion of saturated and unsaturated fatty acids, has important effects on human health. Because intake of saturated fats is correlated with the incidence of cardiovascular disease and diabetes, a goal of metabolic engineering is to develop oils low in saturated fatty acids. Palmitic acid (16:0) is the most abundant saturated fatty acid in the seeds of many oilseed crops and in Arabidopsis thaliana. We expressed FAT-5, a membrane-bound desaturase cloned from Caenorhabditis elegans, in Arabidopsis using a strong seed-specific promoter. The FAT-5 enzyme is highly specific to 16:0 as substrate, converting it to 16:1∆9; expression of fat-5 reduced the 16:0 content of the seed by two-thirds. Decreased 16:0 and elevated 16:1 levels were evident both in the storage and membrane lipids of seeds. Regiochemical analysis of phosphatidylcholine showed that 16:1 was distributed at both positions on the glycerolipid backbone, unlike 16:0, which is predominately found at the sn-1 position. Seeds from a plant line homozygous for FAT-5 expression were comparable to wild type with respect to seed set and germination, while oil content and weight were somewhat reduced. These experiments demonstrate that targeted heterologous expression of a desaturase in oilseeds can reduce the level of saturated fatty acids in the oil, significantly improving its nutritional value. PMID:23279079

  3. Reduced SOD2 expression is associated with mortality of hepatocellular carcinoma patients in a mutant p53-dependent manner

    PubMed Central

    Yang, Xian-Zi; Yang, Yang; Zhang, Mei-Yin; Wang, Hui-Yun; Zheng, X.F. Steven

    2016-01-01

    The development and progression of hepatocellular carcinoma (HCC) is accompanied with persistent oxidative stress, but the molecular basis is not well defined. Superoxide dismutase 2 (SOD2) is an important mitochondrial antioxidant and a key aging factor. Here we investigated the expression and clinical significance of SOD2 in a large cohort of HBV-positive HCC tumors. Both SOD2 mRNA and protein are reduced in human primary HCCs compared with matching liver tissues. Consistently, the SOD2 DNA copy numbers are decreased in HCCs, providing a genetic basis for the decrease in SOD2 mRNA expression. Reduced SOD2 expression in HCCs is correlated with older age, larger tumor size, multiple tumor nodules and tumor emboli, and cancer recurrence. Moreover, low SOD2 expression is strongly associated with poor overall survival (OS) and recurrence-free survival (RFS). Univariate and multivariate Cox regression analyses indicates that SOD2 is an independent prognostic predictor for OS and RFS. Intriguingly, reduced SOD2 mRNA is strongly associated with poor survival in a separate cohort of HCC patients carrying mutant p53. Altogether, our results provide clinical evidence for the importance of SOD2 in tumor progression and mortality, and the close relationship of SOD2 and p53 in HCC. PMID:27221200

  4. Ultrastructural and biochemical studies of two dynamically expressed cell surface determinants on Candida albicans.

    PubMed Central

    Brawner, D L; Cutler, J E

    1986-01-01

    Variability in the expression of two different cell surface carbohydrate determinants was examined with two agglutinating immunoglobulin M monoclonal antibodies (H9 and C6) and immunoelectron microscopy during growth of three strains of Candida albicans. A single strain of Candida parapsilosis did not express either antigen at any time during growth. Antigens were detected on the surface of C. albicans by agglutination tests with either H9 or C6 over a 48-h growth period. The difference in specificities of the monoclonal antibodies was demonstrated by Ouchterlony double-diffusion tests with solubilized antigens and by variabilities in the reactivity of the agglutinins among yeast strains. The antigenic determinants were isolated by specific immunoprecipitation and protease digestion and characterized by methods including high-pressure liquid chromatography, gas-liquid chromatography, and mass spectroscopy with both chemical and electron ionization. These determinants both contain mannose and glucose. In the case of antigen H9, an additional carbohydrate was detected with gas chromatography and mass spectroscopy. The location of antigens on individual cells was determined by indirect labeling of the determinants, first reacting cells with H9 or C6 followed by goat anti-mouse antibody conjugated with 20-nm colloidal gold particles. Transmission electron microscopy was used to examine cells. The antigens that were reactive with the monoclonal antibodies were associated with a flocculent surface layer. Expression of this layer and expression of the antigens is a dynamic process which is growth phase and strain dependent. The antigens were not expressed on very young cells and disappeared from the cell surface of most C. albicans strains with age. The use of monoclonal antibody to cell surface determinants may allow characterization of cell surface antigens of C. albicans and be helpful in establishing receptors which mediate adherence. Images PMID:3510174

  5. Surface expression, peptide repertoire, and thermostability of chicken class I molecules correlate with peptide transporter specificity.

    PubMed

    Tregaskes, Clive A; Harrison, Michael; Sowa, Anna K; van Hateren, Andy; Hunt, Lawrence G; Vainio, Olli; Kaufman, Jim

    2016-01-19

    The chicken major histocompatibility complex (MHC) has strong genetic associations with resistance and susceptibility to certain infectious pathogens. The cell surface expression level of MHC class I molecules varies as much as 10-fold between chicken haplotypes and is inversely correlated with diversity of peptide repertoire and with resistance to Marek's disease caused by an oncogenic herpesvirus. Here we show that the average thermostability of class I molecules isolated from cells also varies, being higher for high-expressing MHC haplotypes. However, we find roughly the same amount of class I protein synthesized by high- and low-expressing MHC haplotypes, with movement to the cell surface responsible for the difference in expression. Previous data show that chicken TAP genes have high allelic polymorphism, with peptide translocation specific for each MHC haplotype. Here we use assembly assays with peptide libraries to show that high-expressing B15 class I molecules can bind a much wider variety of peptides than are found on the cell surface, with the B15 TAPs restricting the peptides available. In contrast, the translocation specificity of TAPs from the low-expressing B21 haplotype is even more permissive than the promiscuous binding shown by the dominantly expressed class I molecule. B15/B21 heterozygote cells show much greater expression of B15 class I molecules than B15/B15 homozygote cells, presumably as a result of receiving additional peptides from the B21 TAPs. Thus, chicken MHC haplotypes vary in several correlated attributes, with the most obvious candidate linking all these properties being molecular interactions within the peptide-loading complex (PLC). PMID:26699458

  6. Surface expression, peptide repertoire, and thermostability of chicken class I molecules correlate with peptide transporter specificity

    PubMed Central

    Tregaskes, Clive A.; Harrison, Michael; Sowa, Anna K.; van Hateren, Andy; Hunt, Lawrence G.; Vainio, Olli; Kaufman, Jim

    2016-01-01

    The chicken major histocompatibility complex (MHC) has strong genetic associations with resistance and susceptibility to certain infectious pathogens. The cell surface expression level of MHC class I molecules varies as much as 10-fold between chicken haplotypes and is inversely correlated with diversity of peptide repertoire and with resistance to Marek’s disease caused by an oncogenic herpesvirus. Here we show that the average thermostability of class I molecules isolated from cells also varies, being higher for high-expressing MHC haplotypes. However, we find roughly the same amount of class I protein synthesized by high- and low-expressing MHC haplotypes, with movement to the cell surface responsible for the difference in expression. Previous data show that chicken TAP genes have high allelic polymorphism, with peptide translocation specific for each MHC haplotype. Here we use assembly assays with peptide libraries to show that high-expressing B15 class I molecules can bind a much wider variety of peptides than are found on the cell surface, with the B15 TAPs restricting the peptides available. In contrast, the translocation specificity of TAPs from the low-expressing B21 haplotype is even more permissive than the promiscuous binding shown by the dominantly expressed class I molecule. B15/B21 heterozygote cells show much greater expression of B15 class I molecules than B15/B15 homozygote cells, presumably as a result of receiving additional peptides from the B21 TAPs. Thus, chicken MHC haplotypes vary in several correlated attributes, with the most obvious candidate linking all these properties being molecular interactions within the peptide-loading complex (PLC). PMID:26699458

  7. Soil solarization reduces Escherichia coli O157:H7 and total Escherichia coli on cattle feedlot pen surfaces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feedlot pen soils are a source for transmission of Escherichia coli O157:H7, and therefore a target for preharvest strategies to reduce this pathogen in cattle. The objective of this study was to determine the ability of soil solarization to reduce E. coli O157:H7 in feedlot surface material (FSM)....

  8. Reduced expression of plasma membrane calcium ATPase 2 and collapsin response mediator protein 1 promotes death of spinal cord neurons.

    PubMed

    Kurnellas, M P; Li, H; Jain, M R; Giraud, S N; Nicot, A B; Ratnayake, A; Heary, R F; Elkabes, S

    2010-09-01

    The mechanisms underlying neuronal pathology and death in the spinal cord (SC) during inflammation remain elusive. We previously showed the important role of plasma membrane calcium ATPases (PMCAs) in the survival of SC neurons, in vitro. We also postulated that a decrease in PMCA2 expression could cause neuronal death during experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. The current studies were undertaken to define the specific contribution of PMCA2 to degeneration of SC neurons, the effectors downstream to PMCA2 mediating neuronal death and the triggers that reduce PMCA2 expression. We report that knockdown of PMCA2 in SC neurons decreases collapsin response mediator protein 1 (CRMP1) levels. This is followed by cell death. Silencing of CRMP1 expression also leads to neuronal loss. Kainic acid reduces both PMCA2 and CRMP1 levels and induces neuronal death. Administration of an alpha-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA)/kainate receptor antagonist, at onset or peak of EAE, restores the decreased PMCA2 and CRMP1 levels to control values and ameliorates clinical deficits. Thus, our data link the reduction in PMCA2 expression with perturbations in the expression of CRMP1 and the ensuing death of SC neurons. This represents an additional mechanism underlying AMPA/kainate receptor-mediated excitotoxicity with relevance to neurodegeneration in EAE. PMID:20489728

  9. Impaired B cell receptor signaling is responsible for reduced TACI expression and function in X-linked immunodeficient mice.

    PubMed

    Uslu, Kadriye; Coleman, Adam S; Allman, Windy R; Katsenelson, Nora; Bram, Richard J; Alugupalli, Kishore R; Akkoyunlu, Mustafa

    2014-04-15

    Immune response to T cell independent type 2 (TI-2) Ags, such as bacterial polysaccharides, is severely impaired in X-linked immunodeficient (XID) mice. In this study, we investigated the involvement of a proliferation-inducing ligand (APRIL) or BAFF and their receptors in the unresponsiveness of XID mouse to TI-2 Ags. We discovered that whereas serum BAFF levels were increased, the expression of the APRIL and BAFF receptor transmembrane activator and calcium-modulator and cyclophilin ligand interactor (TACI) was severely reduced in XID B cells. Moreover, B cells from XID mouse were unable to secrete Igs in response to APRIL or BAFF. In correlation with reduced TACI expression and impaired TACI function, APRIL or BAFF did not activate the classical NF-κB pathway in XID cells. Also correlating with the unaltered expression of BAFF receptor, BAFF stimulation induced the activation of the alternative NF-κB pathway in XID cells. Moreover, activation of MAPK pathway was ablated in APRIL-stimulated XID cells. Prestimulation of XID B cells with the TLR9 agonist, CpG led to a significant increase in TACI expression and restored TACI-mediated functions. CpG prestimulation also restored TACI-mediated signaling in APRIL- or BAFF-stimulated XID B cells. Finally, immunization of XID mouse with the prototype TI-2 Ag NP-Ficoll induced IgG and IgM Abs when CpG was given with NP-Ficoll. Collectively, these results suggest that reduced TACI expression is responsible for the unresponsiveness of XID mouse to TI-2 Ags and BCR activation controls TACI expression. PMID:24646744

  10. Anti-interleukin-33 Reduces Ovalbumin-Induced Nephrotoxicity and Expression of Kidney Injury Molecule-1

    PubMed Central

    2016-01-01

    Purpose: To evaluate the effect of anti-interleukin-33 (anti-IL-33) on a mouse model of ovalbumin (OVA)-induced acute kidney injury (AKI). Methods: Twenty-four female BALB/c mice were assigned to 4 groups: group A (control, n=6) was administered sterile saline intraperitoneally (i.p.) and intranasally (i.n.); group B (allergic, n=6) was administered i.p./i.n. OVA challenge; group C (null treatment, n=6) was administered control IgG i.p. before OVA challenge; and group D (anti-IL-33, n=6) was pretreated with 3.6 µg of anti-IL-33 i.p. before every OVA challenge. The following were evaluated after sacrifice: serum blood urea nitrogen and creatinine levels, Kidney injury molecule-1 gene (Kim-1) and protein (KIM-1) expression in renal parenchyma, and expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), phosphorylated endothelial NOS (p-eNOS), and phosphorylated AMP kinase (p-AMPK) proteins in renal parenchyma. Results: After OVA injection and intranasal challenge, mice in groups B and C showed significant increases in the expression of Kim-1 at both the mRNA and protein levels. After anti-IL-33 treatment, mice in group D showed significant Kim-1 down-regulation at the mRNA and protein levels. Group D also showed significantly lower COX-2 protein expression, marginally lesser iNOS expression than groups B and C, and p-eNOS and p-AMPK expression at baseline levels. Conclusions: Kim-1 could be a useful marker for detecting early-stage renal injury in mouse models of OVA-induced AKI. Further, anti-IL-33 might have beneficial effects on these mouse models. PMID:27377943

  11. Suberoylanilide Hydroxamic Acid Restores Estrogen Reduced-cTnI Expression in Neonatal Hearts of Mice.

    PubMed

    Peng, Chang; Luo, Xiaomei; Xing, Qianlu; Sun, Huichao; Huang, Xupei

    2016-10-01

    Diastolic cardiac dysfunction can be caused by abnormality in cTnI expression during cardiogenesis. In this study, we investigated the effects of estrogen on the abnormal expression of cTnI in the hearts of neonatal mice and its potential epigenetic mechanisms. We then evaluated suberoylanilide hydroxamic acid (SAHA), a HDAC inhibitor, as a new target treatment of diastolic cardiac dysfunction. Postnatal day 0.5 C57BL/6 mice were injected with estrogen for 1 week, then the hearts of 7-day-old neonatal mice were retrieved for examination. The activities of HDAC and HAT were assayed by colorimetry, and the interaction of cTnI with HDAC5 in mice hearts were examined using chromatin immunoprecipitation assays. The expression of cTnI was tested by quantitative real-time RT-PCR and Western blot. Estrogen treated groups displayed a significantly increased HDAC activity in the hearts of neonatal mice while HAT activity remained unchanged. Additionally, HDAC5 was higher at the cTnI promoter, as compared to the saline treated control groups. The acetylation of histone H3K9ac on cTnI promoter significantly decreased in the hearts of neonatal mice treated with estrogen, and the expression of cTnI at transcriptional and protein levels also decreased. SAHA was shown to increase the acetylation of histone H3K9ac and upregulate the expression of cTnI. The data demonstrated that SAHA can correct cTnI expression abnormality caused by estrogen through inhibiting the binding of HDAC5 to the promoter of cTnI. J. Cell. Biochem. 117: 2377-2384, 2016. © 2016 Wiley Periodicals, Inc. PMID:27379430

  12. Femtosecond laser surface texturing of titanium as a method to reduce the adhesion of Staphylococcus aureus and biofilm formation

    NASA Astrophysics Data System (ADS)

    Cunha, Alexandre; Elie, Anne-Marie; Plawinski, Laurent; Serro, Ana Paula; Botelho do Rego, Ana Maria; Almeida, Amélia; Urdaci, Maria C.; Durrieu, Marie-Christine; Vilar, Rui

    2016-01-01

    The aim of the present work was to investigate the possibility of using femtosecond laser surface texturing as a method to reduce the colonization of Grade 2 Titanium alloy surfaces by Staphylococcus aureus and the subsequent formation of biofilm. The laser treatments were carried out with a Yb:KYW chirped-pulse-regenerative amplification laser system with a central wavelength of 1030 nm and a pulse duration of 500 fs. Two types of surface textures, consisting of laser-induced periodic surface structures (LIPSS) and nanopillars, were produced. The topography, chemical composition and phase constitution of these surfaces were investigated by atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, micro-Raman spectroscopy, and X-ray diffraction. Surface wettability was assessed by the sessile drop method using water and diiodomethane as testing liquids. The response of S. aureus put into contact with the laser treated surfaces in controlled conditions was investigated by epifluorescence microscopy and scanning electron microscopy 48 h after cell seeding. The results achieved show that the laser treatment reduces significantly the bacterial adhesion to the surface as well as biofilm formation as compared to a reference polished surfaces and suggest that femtosecond laser texturing is a simple and promising method for endowing dental and orthopedic titanium implants with antibacterial properties, reducing the risk of implant-associated infections without requiring immobilized antibacterial substances, nanoparticles or coatings.

  13. Surface expression and cytolytic function of natural killer cell receptors is altered in chronic hepatitis C

    PubMed Central

    Nattermann, J; Feldmann, G; Ahlenstiel, G; Langhans, B; Sauerbruch, T; Spengler, U

    2006-01-01

    Introduction Impaired activity of natural killer (NK) cells has been proposed as a mechanism contributing to viral persistence in hepatitis C virus (HCV) infection. As the function of NK cells is primarily regulated by NK cell receptors (NKR), we analysed whether decreased NK cell function in hepatitis C may be related to dysregulated NKR expression. Patients and methods Expression of NK cell was analysed by flow cytometry on lymphocytes from HCV(+) subjects (n = 30), patients who became HCV(−) after antiviral therapy (n = 10), healthy individuals (n = 10), and hepatitis B virus (HBV) infected patients (n = 9). Cytolytic function of lymphocytes was studied in a redirected lysis assay and in a standard 51chromium release cytotoxicity assay, respectively. Results In patients with chronic hepatitis C, we found a significantly reduced proportion of NKp46 and NKp30 expressing NK cells compared with healthy and HBV infected subjects. Low expression of natural cytotoxicity receptor (NCR) was also confirmed in in vitro activated NK cell populations derived from HCV patients compared with uninfected donors. In contrast, patients who cleared HCV under antiviral therapy showed normal expression of NKp44, NKp30, and NKp46. Reduced NCR expression in chronic hepatitis C was associated with a parallel decrease in NCR mediated target cell killing. Furthermore, we found a significantly increased proportion of NKG2A expressing NK cells and CD8+ T cells in HCV positive patients, resulting in a reduced cytolytic activity against cells incubated with the HLA‐E stabilising peptide HCV core35–44. Conclusion The present study indicates that defective expression of NKR represents a novel mechanism contributing to impaired function of NK cells and CD8+ T cells in chronic hepatitis C. PMID:16322112

  14. Specific tracheal migration is mediated by complementary expression of cell surface proteins

    PubMed Central

    Boube, Muriel; Martin-Bermudo, Maria D.; Brown, Nicholas H.; Casanova, Jordi

    2001-01-01

    Migration of the Drosophila tracheal cells relies on cues provided by nearby cells; however, little is known about how these signals specify a migratory path. Here we investigate the role of cell surface proteins in the definition of such a pathway. We have found that the PS1 integrin is required in the tracheal cells of the visceral branch, whereas the PS2 integrin is required in the visceral mesoderm; both integrins are necessary for the spreading of the visceral branch over its substratum. This is the first identification of a cell surface molecule with expression restricted to a subset of tracheal cells that all migrate in a given direction. We have also found that expression of PS1 in the visceral branch is regulated by the genes that direct tracheal cell migration, showing that integrin expression is part of the cell-fate program that they specify. These results support a model in which signal transduction determines the tracheal migratory pathways by regulating the expression of cell surface proteins, which in turn interact with surface molecules on the surrounding cell population. PMID:11410535

  15. Multiple Effects of Mutation on Expression of Alternative Cell Surface Protein Genes in Tetrahymena Thermophila

    PubMed Central

    Smith, D. L.; Doerder, F. P.

    1992-01-01

    Genes at the SerH locus of the ciliated protist Tetrahymena thermophila specify the major (H) surface protein on cells grown at 20-36°. Alternative proteins L, T, S and I are expressed under different conditions of temperature and culture media. Mutants unable to express SerH genes were examined for expression of these proteins, also called immobilization or i-antigens, at both H and non-H conditions. In all instances, one or more i-antigens were expressed in the absence of H, and, in most instances, expression of i-antigens under non-H conditions was also affected. Examples of the latter include both the continued expression of H-replacement antigens and the inability to express certain other i-antigens. Such multiple effects were observed in mutants with trans-acting (rseA, rseB, rseC, RseD) and cis-acting (H1-1 and H1-2) mutations, but not in mutants in which SerH is affected developmentally (B2092, B2101, B2103, B2107). These interactions suggest that the wild-type genes identified by mutation exert both positive and negative effects in the regulation of i-antigen gene expression. PMID:1732170

  16. High sea surface temperatures driven by a strengthening current reduce foraging success by penguins

    PubMed Central

    Carroll, Gemma; Everett, Jason D.; Harcourt, Robert; Slip, David; Jonsen, Ian

    2016-01-01

    The world’s oceans are undergoing rapid, regionally specific warming. Strengthening western boundary currents play a role in this phenomenon, with sea surface temperatures (SST) in their paths rising faster than the global average. To understand how dynamic oceanography influences food availability in these ocean warming “hotspots”, we use a novel prey capture signature derived from accelerometry to understand how the warm East Australian Current shapes foraging success by a meso-predator, the little penguin. This seabird feeds on low trophic level species that are sensitive to environmental change. We found that in 2012, prey capture success by penguins was high when SST was low relative to the long-term mean. In 2013 prey capture success was low, coincident with an unusually strong penetration of warm water. Overall there was an optimal temperature range for prey capture around 19–21 °C, with lower success at both lower and higher temperatures, mirroring published relationships between commercial sardine catch and SST. Spatially, higher SSTs corresponded to a lower probability of penguins using an area, and lower prey capture success. These links between high SST and reduced prey capture success by penguins suggest negative implications for future resource availability in a system dominated by a strengthening western boundary current. PMID:26923901

  17. Containment of a silicone fluid free surface in reduced gravity using barrier coatings

    NASA Technical Reports Server (NTRS)

    Pline, Alexander D.; Jacobson, Thomas P.

    1988-01-01

    In support of the Surface Tension Driven Convection Experiment planned for flight aboard the Space Shuttle, tests were conducted under reduced gravity in the 2.2-sec Drop Tower and the 5.0-sec Zero-G facility at the NASA Lewis Research Center. The dynamics of controlling the test fluid, a 10-cSt viscosity silicone fluid in a low gravity environment were investigated using different container designs and barrier coatings. Three container edge designs were tested without a barrier coating; a square edge, a sharp edge with a 45-deg slope, and a sawtooth edge. All three edge designs were successful in containing the fluid below the edge. G-jitter experiments were made in scaled down containers subjected to horizontal accelerations. The data showed that a barrier coating is effective in containing silicone fluid under g-levels up to 10 sup -1 sub g sub 0. In addition, a second barrier coating was found which has similar anti-wetting characteristics and is also more durable.

  18. Surface color perception under two illuminants: the second illuminant reduces color constancy

    NASA Technical Reports Server (NTRS)

    Yang, Joong Nam; Shevell, Steven K.

    2003-01-01

    This study investigates color perception in a scene with two different illuminants. The two illuminants, in opposite corners, simultaneously shine on a (simulated) scene with an opaque dividing wall, which controls how much of the scene is illuminated by each source. In the first experiment, the height of the dividing wall was varied. This changed the amount of each illuminant reaching objects on the opposite side of the wall. Results showed that the degree of color constancy decreased when a region on one side of the wall had cues to both illuminants, suggesting that cues from the second illuminant are detrimental to color constancy. In a later experiment, color constancy was found to improve when the specular highlight cues from the second illuminant were altered to be consistent with the first illuminant. This corroborates the influence of specular highlights in surface color perception, and suggests that the reduced color constancy in the first experiment is due to the inconsistent, though physically correct, cues from the two illuminants.

  19. The role of wastewater treatment in reducing pollution of surface waters with zearalenone.

    PubMed

    Gromadzka, Karolina; Waśkiewicz, Agnieszka; Świetlik, Joanna; Bocianowski, Jan; Goliński, Piotr

    2015-06-01

    Zearalenone (ZEA) is a mycotoxin produced by some Fusarium species in food and feed. The toxicity of ZEA and its metabolites is related to the chemical structure of the mycotoxin, which is similar to naturally occurring oestrogens. Currently, there is increasing awareness of the presence of fungi and their toxic metabolites in the aquatic environment. One of the sources of these compounds are the effluents from wastewater treatment plants. The average annual efficiency of zearalenone reduction in the Łęczyca plant in our three-year study was in the range from 51.35 to 69.70 %. The threeway analysis of variance (year, month, and kind of wastewater) shows that the main effects of all factors and all interactions between them were significant for zearalenone and dissolved organic carbon content. Our findings suggest that wastewater is not the main source of surface water pollution with zearalenone. Future research should investigate the means to reduce ZEA and its migration from the fields through prevention strategies such as breeding for crops, plant debris management (crop rotation, tillage), and/or chemical and biological control. PMID:26110478

  20. High sea surface temperatures driven by a strengthening current reduce foraging success by penguins.

    PubMed

    Carroll, Gemma; Everett, Jason D; Harcourt, Robert; Slip, David; Jonsen, Ian

    2016-01-01

    The world's oceans are undergoing rapid, regionally specific warming. Strengthening western boundary currents play a role in this phenomenon, with sea surface temperatures (SST) in their paths rising faster than the global average. To understand how dynamic oceanography influences food availability in these ocean warming "hotspots", we use a novel prey capture signature derived from accelerometry to understand how the warm East Australian Current shapes foraging success by a meso-predator, the little penguin. This seabird feeds on low trophic level species that are sensitive to environmental change. We found that in 2012, prey capture success by penguins was high when SST was low relative to the long-term mean. In 2013 prey capture success was low, coincident with an unusually strong penetration of warm water. Overall there was an optimal temperature range for prey capture around 19-21 °C, with lower success at both lower and higher temperatures, mirroring published relationships between commercial sardine catch and SST. Spatially, higher SSTs corresponded to a lower probability of penguins using an area, and lower prey capture success. These links between high SST and reduced prey capture success by penguins suggest negative implications for future resource availability in a system dominated by a strengthening western boundary current. PMID:26923901

  1. Reduced secretion of IgA to skin surface of patients with atopic dermatitis.

    PubMed

    Imayama, S; Shimozono, Y; Hoashi, M; Yasumoto, S; Ohta, S; Yoneyama, K; Hori, Y

    1994-08-01

    To investigate whether the secretory form of immunoglobulin A (sIgA) was reduced on the skin surface in atopic dermatitis, the amount of sIgA present in sweat was measured in 40 patients with atopic dermatitis and in 50 healthy volunteers by attaching a cellulose membrane disk (10 x 10 mm) to the inner aspect of the upper arm skin for 24 hours. The secretory form of IgA, which was absorbed to the membrane and accumulated during the period of application, was revealed as dots by an enzyme immunoassay in which antibodies for IgA and for the secretory component were used. The density and number of dots (per mm2/day), which corresponded to the openings of eccrine excretory ducts, were determined with a densitometer. The mean amount of sIgA secreted by those patients was 3.86 +/- 0.71 pg/mm2/day (range, 0 to 21.17 pg/mm2/day), whereas that of the control subjects was significantly higher (p < 0.001), 16.79 +/- 2.80 pg/mm2/day (range, 0.79 to 133.77 pg/mm2/day). This may be related to the high incidence of bacterial and viral skin infections seen in patients with atopic dermatitis, and in addition, to the development of eczematous lesions through a defect in ridding the skin of allergens and/or microorganisms. PMID:8064071

  2. Variable Source Watershed Model for Reducing Dissolved Phosphorus Concentrations in Surface Waters

    NASA Astrophysics Data System (ADS)

    Steenhuis, T. S.; Hoang, L.; Schneiderman, E. M.; Pacenka, S.; Vermeulen, P. J.; Moore, K. E.; Owens, E. M.

    2015-12-01

    Although established procedures for treatment of point sources have been available for the last fifty years, effective and efficient management procedures for reducing non-point source pollution are still being developed. One of the reasons for the slow development is that the various management practices need to be tailored to the landscape in order to be optimal. Water quality simulation models for watersheds would be ideal for designing these effective practices but in many cases are only validated at the watershed outlet where the monitored data are available which does not guarantee that the spatial distribution of runoff and pollution sources inside the watershed are simulated correctly. Especially, in rural, humid regions where runoff is associated with saturation-excess processes from variable source areas our modeling of the hydrology and water quality is limiting. Recently, we adapted successfully a watershed model El-SWAT that realistically can simulate saturation excess surface runoff and interflow by introducing a perched water table reservoir that can transfer water via the subsurface to the wet areas in the watershed and thereby overcomes one of the major limitation of the SWAT model. For this presentation, we have combined El-SWAT with a set of spatially dependent phosphorus sub routines developed by us for simulating spatially dependent phosphorus losses in upstate New York State. In this presentation we will show its application in designing effective best management practices in the New York City Source Watersheds in the Catskill Mountains.

  3. Laser surface modification of medical grade alloys for reduced heating in a magnetic resonance imaging environment

    SciTech Connect

    Benafan, O. E-mail: raj@ucf.edu; Vaidyanathan, R. E-mail: raj@ucf.edu; Chen, S.-Y.; Kar, A.

    2015-12-15

    Nanoscale surface modification of medical grade metallic alloys was conducted using a neodymium-doped yttrium aluminum garnet laser-based dopant diffusion technique. The objective of this approach was to minimize the induction heating by reducing the absorbed radio frequency field. Such an approach is advantageous in that the dopant is diffused into the alloy and is not susceptible to detachment or spallation as would an externally applied coating, and is expected to not deteriorate the mechanical and electrical properties of the base alloy or device. Experiments were conducted using a controlled environment laser system with the ability to control laser properties (i.e., laser power, spot size, and irradiation time) and dopant characteristics (i.e., temperature, concentration, and pressure). The reflective and transmissive properties of both the doped and untreated samples were measured in a radio frequency (63.86 MHz) magnetic field using a system comprising a high power signal generator, a localized magnetic field source and sensor, and a signal analyzer. The results indicate an increase in the reflectivity of the laser-treated samples compared to untreated samples. The effect of reflectivity on the heating of the alloys is investigated through a mathematical model incorporating Maxwell’s equations and heat conduction.

  4. Laser surface modification of medical grade alloys for reduced heating in a magnetic resonance imaging environment.

    PubMed

    Benafan, O; Chen, S-Y; Kar, A; Vaidyanathan, R

    2015-12-01

    Nanoscale surface modification of medical grade metallic alloys was conducted using a neodymium-doped yttrium aluminum garnet laser-based dopant diffusion technique. The objective of this approach was to minimize the induction heating by reducing the absorbed radio frequency field. Such an approach is advantageous in that the dopant is diffused into the alloy and is not susceptible to detachment or spallation as would an externally applied coating, and is expected to not deteriorate the mechanical and electrical properties of the base alloy or device. Experiments were conducted using a controlled environment laser system with the ability to control laser properties (i.e., laser power, spot size, and irradiation time) and dopant characteristics (i.e., temperature, concentration, and pressure). The reflective and transmissive properties of both the doped and untreated samples were measured in a radio frequency (63.86 MHz) magnetic field using a system comprising a high power signal generator, a localized magnetic field source and sensor, and a signal analyzer. The results indicate an increase in the reflectivity of the laser-treated samples compared to untreated samples. The effect of reflectivity on the heating of the alloys is investigated through a mathematical model incorporating Maxwell's equations and heat conduction. PMID:26724043

  5. Evaluation of an ATP Assay to Quantify Bacterial Attachment to Surfaces in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Birmele, Michele N.; Roberson, Luke B.; Roberts, Michael S.

    2010-01-01

    Aim: To develop an assay to quantify the biomass of attached cells and biofilm formed on wetted surfaces in variable-gravity environments. Methods and Results: Liquid cultures of Pseudomonas aeruginosa were exposed to 30-35 brief cycles of hypergravity (< 2-g) followed by free fall (i.e., reduced gravity) equivalent to either lunar-g (i.e., 0.17 normal Earth gravity) or micro-g (i.e., < 0.001 normal Earth gravity) in an aircraft flying a series of parabolas. Over the course of two days of parabolic flight testing, 504 polymer or metal coupons were exposed to a stationary-phase population of P. aeruginosa strain ERC1 at a concentration of 1.0 x 10(exp 5) cells per milliliter. After the final parabola on each flight test day, half of the material coupon samples were treated with either 400 micro-g/L ionic silver fluoride (microgravity-exposed cultures) or 1% formalin (lunar-gravity-exposed cultures). The remaining sample coupons from each flight test day were not treated with a fixative. All samples were returned to the laboratory for analysis within 2 hours of landing, and all biochemical assays were completed within 8 hours of exposure to variable gravity. The intracellular ATP luminescent assay accurately reflected cell physiology compared to both cultivation-based and direct-count microscopy analyses. Cells exposed to variable gravity had more than twice as much intracellular ATP as control cells exposed only to normal Earth gravity.

  6. Laser surface modification of medical grade alloys for reduced heating in a magnetic resonance imaging environment

    NASA Astrophysics Data System (ADS)

    Benafan, O.; Chen, S.-Y.; Kar, A.; Vaidyanathan, R.

    2015-12-01

    Nanoscale surface modification of medical grade metallic alloys was conducted using a neodymium-doped yttrium aluminum garnet laser-based dopant diffusion technique. The objective of this approach was to minimize the induction heating by reducing the absorbed radio frequency field. Such an approach is advantageous in that the dopant is diffused into the alloy and is not susceptible to detachment or spallation as would an externally applied coating, and is expected to not deteriorate the mechanical and electrical properties of the base alloy or device. Experiments were conducted using a controlled environment laser system with the ability to control laser properties (i.e., laser power, spot size, and irradiation time) and dopant characteristics (i.e., temperature, concentration, and pressure). The reflective and transmissive properties of both the doped and untreated samples were measured in a radio frequency (63.86 MHz) magnetic field using a system comprising a high power signal generator, a localized magnetic field source and sensor, and a signal analyzer. The results indicate an increase in the reflectivity of the laser-treated samples compared to untreated samples. The effect of reflectivity on the heating of the alloys is investigated through a mathematical model incorporating Maxwell's equations and heat conduction.

  7. Thymoquinone inhibits cancer metastasis by downregulating TWIST1 expression to reduce epithelial to mesenchymal transition

    PubMed Central

    Khan, Md. Asaduzzaman; Tania, Mousumi; Wei, Chunli; Mei, Zhiqiang; Fu, Shelly; Cheng, Jingliang; Xu, Jianming; Fu, Junjiang

    2015-01-01

    Proteins that promote epithelial to mesenchymal transition (EMT) are associated with cancer metastasis. Inhibition of EMT regulators may be a promising approach in cancer therapy. In this study, Thymoquinone (TQ) was used to treat cancer cell lines to investigate its effects on EMT-regulatory proteins and cancer metastasis. We show that TQ inhibited cancer cell growth, migration and invasion in a dose-dependent manner. At the molecular level, TQ treatment decreased the transcriptional activity of the TWIST1 promoter and the mRNA expression of TWIST1, an EMT-promoting transcription factor. Accordingly, TQ treatment also decreased the expression of TWIST1-upregulated genes such as N-Cadherin and increased the expression of TWIST1-repressed genes such as E-Cadherin, resulting in a reduction of cell migration and invasion. TQ treatment also inhibited the growth and metastasis of cancer cell-derived xenograft tumors in mice but partially attenuated the migration and invasion in TWIST1-overexpressed cell lines. Furthermore, we found that TQ treatment enhanced the promoter DNA methylation of the TWIST1 gene in BT 549 cells. Together, these results demonstrate that TQ treatment inhibits TWIST1 promoter activity and decreases its expression, leading to the inhibition of cancer cell migration, invasion and metastasis. These findings suggest TQ as a potential small molecular inhibitor of cancer growth and metastasis. PMID:26023736

  8. Expression of a foreign Rubisco small subunit in tobacco with reduced levels of the native protein

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cDNA, ArRbcS3, for the small subunit of Rubisco from Amaranthus retroflexus (pigweed) was expressed in tobacco (Nicotiana tabacum) under the control of a strong leaf-specific Lhcb promoter. The coding region of the ArRbcS3 was fused to the plastid targeting sequence of the native tobacco rbcS to...

  9. Suppressing male spermatogenesis-associated protein 5-like gene expression reduces vitellogenin gene expression and fecundity in Nilaparvata lugens Stål

    PubMed Central

    Ge, Lin-Quan; Xia, Ting; Huang, Bo; Song, Qi-Sheng; Zhang, Hong-Wei; Stanley, David; Yang, Guo-Qing; Wu, Jin-Cai

    2016-01-01

    In our previous study with the brown planthopper (BPH), Nilaparvata lugens, triazophos (tzp) treatments led to substantial up-regulation of a male spermatogenesis-associated protein 5-like gene (NlSPATA5) compared to untreated controls. Mating with tzp-treated males significantly increased fecundity (as numbers of eggs laid), relative to females mated with untreated males. Because SPATA5 acts in mammalian sperm development and is expressed in testes, we posed the hypothesis that NlSPATA5 occurs in BPH seminal fluid and it operates in fecundity via mating. We tested the hypothesis by investigating the influence of suppressing NlSPATA5 expression in BPH males on fecundity. Reduced expression of NlSPATA5 led to decreased male accessory gland protein content and reproductive system development compared to controls. These changes in males led to prolonged pre-oviposition periods and decreased fecundity in females. For both genders, we recorded no difference in the body weight, oviposition periods, and longevity compared to controls. NlSPATA5 suppression in males also led to decreased fat body and ovarian protein content, yeast-like symbionts abundance and ovarian development as well as vitellogenin gene expression in their mating partners. We infer that increased NlSPATA5 expression may be one molecular mechanism of tzp-driven reproduction and population increases in BPH. PMID:27305948

  10. Suppressing male spermatogenesis-associated protein 5-like gene expression reduces vitellogenin gene expression and fecundity in Nilaparvata lugens Stål.

    PubMed

    Ge, Lin-Quan; Xia, Ting; Huang, Bo; Song, Qi-Sheng; Zhang, Hong-Wei; Stanley, David; Yang, Guo-Qing; Wu, Jin-Cai

    2016-01-01

    In our previous study with the brown planthopper (BPH), Nilaparvata lugens, triazophos (tzp) treatments led to substantial up-regulation of a male spermatogenesis-associated protein 5-like gene (NlSPATA5) compared to untreated controls. Mating with tzp-treated males significantly increased fecundity (as numbers of eggs laid), relative to females mated with untreated males. Because SPATA5 acts in mammalian sperm development and is expressed in testes, we posed the hypothesis that NlSPATA5 occurs in BPH seminal fluid and it operates in fecundity via mating. We tested the hypothesis by investigating the influence of suppressing NlSPATA5 expression in BPH males on fecundity. Reduced expression of NlSPATA5 led to decreased male accessory gland protein content and reproductive system development compared to controls. These changes in males led to prolonged pre-oviposition periods and decreased fecundity in females. For both genders, we recorded no difference in the body weight, oviposition periods, and longevity compared to controls. NlSPATA5 suppression in males also led to decreased fat body and ovarian protein content, yeast-like symbionts abundance and ovarian development as well as vitellogenin gene expression in their mating partners. We infer that increased NlSPATA5 expression may be one molecular mechanism of tzp-driven reproduction and population increases in BPH. PMID:27305948

  11. Reduced expression of β-catenin inhibitor Chibby in colon carcinoma cell lines

    PubMed Central

    Schuierer, Marion M; Graf, Elisabeth; Takemaru, Ken-Ichi; Dietmaier, Wolfgang; Bosserhoff, Anja-Katrin

    2006-01-01

    AIM: To analyse the Chibby expression and its function in colon carcinoma cell lines and colorectal carcinoma (CRC). METHODS: Chibby expression levels were investigated by quantitative RT-PCR in a panel of seven different colon carcinoma cell lines. By sequencing, we analysed mutational status of Chibby. To test whether Chibby exhibited effects on β-catenin signalling in colon carcinoma cells, we transfected SW480 cells with Chibby expression plasmid and, subsequently, analysed activity of β-catenin and tested for alterations in cellular phenotype. In addition, we examined Chibby mRNA levels in samples of colorectal carcinomas and adjacent normal tissues by using quantitative RT-PCR and hybridised gene chips with samples from CRC and normal tissues. RESULTS: Chibby mRNA expression was strongly down-regulated in colon carcinoma cell lines in comparison to normal colon epithelial cells and no mutation in any of the examined colon carcinoma cell lines was found. Further, we could show that Chibby inhibited β-catenin activity in TOPflash assays when over-expressed in SW480 cells. Proliferation and invasion assays with Chibby transfected SW480 cells did not reveal profound differences compared to control cells. In contrast to these in vitro data, quantitative RT-PCR analyses of Chibby mRNA levels in CRC tumor samples did not show significant differences to specimens in adjacent non-cancerous tissue. Consistent with these findings, gene chips analysing tissue samples of tumors and corresponding normal tissue did not show altered Chibby expression CONCLUSION: Altered Chibby expression might be observed in vitro in different colon carcinoma cell lines. However, this finding could not be confirmed in vitro in CRC tumors, indicating that Chibby is not likely to promote CRC tumor development or progression. As Chibby is an important inhibitor of ß-catenin signalling, our data implicate that the usability of colon carcinoma cell lines for in vitro studies analysing the Wnt

  12. Dysregulated expression of cell surface glycoprotein CDCP1 in prostate cancer

    PubMed Central

    Yang, Lifang; Dutta, Sucharita M.; Troyer, Dean A.; Lin, Jefferson B.; Lance, Raymond A.; Nyalwidhe, Julius O.; Drake, Richard R; Semmes, O. John

    2015-01-01

    CUB-domain-containing protein 1 (CDCP1) is a trans-membrane protein regulator of cell adhesion with a potent pro-migratory function in tumors. Given that proteolytic cleavage of the ectodomain correlates with outside-in oncogenic signaling, we characterized glycosylation in the context of cellular processing and expression of CDCP1 in prostate cancer. We detected 135 kDa full-length and proteolytic processed 70 kDa species in a panel of PCa cell models. The relative expression of full-length CDCP1 correlated with the metastatic potential of syngeneic cell models and an increase in surface membrane expression of CDCP1 was observed in tumor compared to adjacent normal prostate tissues. We demonstrated that glycosylation of CDCP1 is a prerequisite for protein stability and plasma membrane localization, and that the expression level and extent of N-glycosylation of CDCP1 correlated with metastatic status. Interestingly, complex N-linked glycans with sialic acid chains were restricted to the N-terminal half of the ectodomain and absent in the truncated species. Characterization of the extracellular expression of CDCP1 identified novel circulating forms and revealed that extracellular vesicles provide additional processing pathways. Employing immunoaffinity mass spectrometry, we detected elevated levels of circulating CDCP1 in patient urine with high-risk disease. Our results establish that differential glycosylation, cell surface presentation and extracellular expression of CDCP1 are hallmarks of PCa progression. PMID:26497208

  13. Optimization of Recombinant Expression of Synthetic Bacterial Phytase in Pichia pastoris Using Response Surface Methodology

    PubMed Central

    Akbarzadeh, Ali; Dehnavi, Ehsan; Aghaeepoor, Mojtaba; Amani, Jafar

    2015-01-01

    Background: Escherichia coli phytase is an acidic histidine phytase with great specific activity. Pichia pastoris is a powerful system for the heterologous expression of active and soluble proteins which can express recombinant proteins in high cell density fermenter without loss of product yield and efficiently secrete heterologous proteins into the media. Recombinant protein expression is influenced by expression conditions such as temperature, concentration of inducer, and pH. By optimization, the yield of expressed proteins can be increase. Response surface methodology (RSM) has been widely used for the optimization and studying of different parameters in biotechnological processes. Objectives: In this study, the expression of synthetic appA gene in P. pastoris was greatly improved by adjusting the expression condition. Materials and Methods: The appA gene with 410 amino acids was synthesized by P. pastoris codon preference and cloned in expression vector pPinkα-HC, under the control of AOX1 promoter, and it was transformed into P. pastoris GS115 by electroporation. Recombinant phytase was expressed in buffered methanol-complex medium (BMMY) and the expression was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and enzymatic assay. To achieve the highest level of expression, methanol concentration, pH and temperature were optimized via RSM. Finally, the optimum pH and temperature for recombinant phytase activity was determined. Results: Escherichia coli phytase was expressed in P. pastoris under different cultivation conditions (post-induction temperature, methanol concentration, and post-induction pH). The optimized conditions by RSM using face centered central composite design were 1% (v/v) methanol, pH = 5.8, and 24.5°C. Under the optimized conditions, appA was successfully expressed in P. pastoris and the maximum phytase activity was 237.2 U/mL after 72 hours of expression. Conclusions: By optimization of recombinant

  14. Reduced proximal tubule angiotensin II receptor expression in streptozotocin-induced diabetes mellitus.

    PubMed

    Cheng, H F; Burns, K D; Harris, R C

    1994-12-01

    Diabetes mellitus is characterized by alterations in the intrarenal renin-angiotensin system, including decreases in glomerular angiotensin II (Ang II) receptor density. Since Ang II regulates proximal tubule transport function, the present studies examined whether diabetes altered expression of proximal tubule receptors. In basolateral membranes from 14 day streptozotocin-induced diabetic rats, specific binding of 125I Ang II was decreased to 53 +/- 8% of control (3.2 +/- 0.5 vs. 1.5 +/- 0.2 fmol/mg protein; N = 7; P < 0.02). Similarly, in proximal tubule brush border membranes from diabetic animals, specific binding was decreased to 63 +/- 11% of control (1.1 +/- 0.2 vs 0.6 +/- 0.1 fmol/mg protein; N = 9; P < 0.05). Concomitant insulin treatment reversed the decrease in specific binding of 125I Ang II to basolateral membranes (109 +/- 26% of control; N = 3) and to brush border membranes (85 +/- 17% of control; N = 6). In order to determine if changes in expression of type-1 Ang II receptors (AT1R) accompanied the changes in binding, quantitative polymerase chain reaction of AT1R mRNA was performed and expressed as the ratio of the amplified AT1R to that of an Msc1/Msc1 internal deletion mutant and normalized to that of beta-actin. In total RNA from proximal tubule suspensions of diabetic animals, AT1R mRNA expression decreased by 38% (21 +/- 3 vs. 13 +/- 2 cpm AT1R/cpm deletion mutant/cpm beta actin/10(6); N = 4; P < 0.0025). Insulin treatment reverted AT1R mRNA expression to control levels (22 +/- 3 cpm AT1R/cpm deletion mutant/cpm beta actin/10(6); P < 0.001 compared to the untreated group).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7700017

  15. Interactive Exploration of Microarray Gene Expression Patterns in a Reduced Dimensional Space

    PubMed Central

    Misra, Jatin; Schmitt, William; Hwang, Daehee; Hsiao, Li-Li; Gullans, Steve; Stephanopoulos, George; Stephanopoulos, Gregory

    2002-01-01

    The very high dimensional space of gene expression measurements obtained by DNA microarrays impedes the detection of underlying patterns in gene expression data and the identification of discriminatory genes. In this paper we show the use of projection methods such as principal components analysis (PCA) to obtain a direct link between patterns in the genes and patterns in samples. This feature is useful in the initial interactive pattern exploration of gene expression data and data-driven learning of the nature and types of samples. Using oligonucleotide microarray measurements of 40 samples from different normal human tissues, we show that distinct patterns are obtained when the genes are projected on a two-dimensional plane spanned by the loadings of the two major principal components. These patterns define the particular genes associated with a sample class (i.e., tissue). When used separately from the other genes, these class-specific (i.e., tissue-specific) genes in turn define distinct tissue patterns in the projection space spanned by the scores of the two major principal components. In this study, PCA projection facilitated discriminatory gene selection for different tissues and identified tissue-specific gene expression signatures for liver, skeletal muscle, and brain samples. Furthermore, it allowed the classification of nine new samples belonging to these three types using the linear combination of the expression levels of the tissue-specific genes determined from the first set of samples. The application of the technique to other published data sets is also discussed. [Online supplementary material available at www.genome.org.] PMID:12097349

  16. Long-term controlled GDNF over-expression reduces dopamine transporter activity without affecting tyrosine hydroxylase expression in the rat mesostriatal system.

    PubMed

    Barroso-Chinea, Pedro; Cruz-Muros, Ignacio; Afonso-Oramas, Domingo; Castro-Hernández, Javier; Salas-Hernández, Josmar; Chtarto, Abdelwahed; Luis-Ravelo, Diego; Humbert-Claude, Marie; Tenenbaum, Liliane; González-Hernández, Tomás

    2016-04-01

    The dopamine (DA) transporter (DAT) is a plasma membrane glycoprotein expressed in dopaminergic (DA-) cells that takes back DA into presynaptic neurons after its release. DAT dysfunction has been involved in different neuro-psychiatric disorders including Parkinson's disease (PD). On the other hand, numerous studies support that the glial cell line-derived neurotrophic factor (GDNF) has a protective effect on DA-cells. However, studies in rodents show that prolonged GDNF over-expression may cause a tyrosine hydroxylase (TH, the limiting enzyme in DA synthesis) decline. The evidence of TH down-regulation suggests that another player in DA handling, DAT, may also be regulated by prolonged GDNF over-expression, and the possibility that this effect is induced at GDNF expression levels lower than those inducing TH down-regulation. This issue was investigated here using intrastriatal injections of a tetracycline-inducible adeno-associated viral vector expressing human GDNF cDNA (AAV-tetON-GDNF) in rats, and doxycycline (DOX; 0.01, 0.03, 0.5 and 3mg/ml) in the drinking water during 5weeks. We found that 3mg/ml DOX promotes an increase in striatal GDNF expression of 12× basal GDNF levels and both DA uptake decrease and TH down-regulation in its native and Ser40 phosphorylated forms. However, 0.5mg/ml DOX promotes a GDNF expression increase of 3× basal GDNF levels with DA uptake decrease but not TH down-regulation. The use of western-blot under non-reducing conditions, co-immunoprecipitation and in situ proximity ligation assay revealed that the DA uptake decrease is associated with the formation of DAT dimers and an increase in DAT-α-synuclein interactions, without changes in total DAT levels or its compartmental distribution. In conclusion, at appropriate GDNF transduction levels, DA uptake is regulated through DAT protein-protein interactions without interfering with DA synthesis. PMID:26777664

  17. Hypoxia/hepatoma dual specific suicide gene expression plasmid delivery using bio-reducible polymer for hepatocellular carcinoma therapy.

    PubMed

    Kim, Hyun Ah; Nam, Kihoon; Lee, Minhyung; Kim, Sung Wan

    2013-10-10

    Gene therapy is suggested as a promising alternative strategy of hepatocellular carcinoma (HCC, also called hepatoma) therapy. To achieve a successful and safe gene therapy, tight regulation of gene expression is required to minimize side-effects in normal tissues. In this study, we developed a novel hypoxia and hepatoma dual specific gene expression vector. The constructed vectors were transfected into various cell lines using bio-reducible polymer, PAM-ABP. First, pAFPS-Luc or pAFPL-Luc vector was constructed with the alpha-fectoprotein (AFP) promoter and enhancer for hepatoma tissue specific gene expression. Then, pEpo-AFPL-Luc was constructed by insertion of the erythropoietin (Epo) enhancer for hypoxic cancer specific gene expression. In vitro transfection assay showed that pEpo-AFPL-Luc transfected hepatoma cell increased gene expression under hypoxic condition. To confirm the therapeutic effect of dual specific vector, herpes simplex virus thymidine kinase (HSV-TK) gene was introduced for cancer cell killing. The pEpo-AFPL-TK was transfected into hepatoma cell lines in the presence of ganciclovir (GCV) pro-drug. Caspase-3/7, MTT and TUNEL assays elucidated that pEpo-AFPL-TK transfected cells showed significant increasing of death rate in hypoxic hepatoma cells compared to controls. Therefore, the hypoxia/hepatoma dual specific gene expression vector with the Epo enhancer and AFP promoter may be useful for hepatoma specific gene therapy. PMID:23830978

  18. Expression of a repeating phosphorylated disaccharide lipophosphoglycan epitope on the surface of macrophages infected with Leishmania donovani.

    PubMed

    Tolson, D L; Turco, S J; Pearson, T W

    1990-11-01

    Murine peritoneal macrophages were infected with living, virulent Leishmania donovani promastigotes. At intervals after infection, the macrophage surfaces were probed for the expression of lipophosphoglycan (LPG) epitopes by immunofluorescence with anti-LPG monoclonal antibodies. A repeating phosphorylated disaccharide epitope of LPG was detected as early as 5 to 10 min postinfection and was initially localized to the immediate area of internalization of the promastigote into the macrophage. The epitopes were evenly distributed over the entire macrophage surface by 25 min postinfection. Treatments which inhibited macrophage phagolysosomal degradation processes had no effect on epitope expression, whereas reagents that affected macrophage membrane flow and, thus, phagocytosis drastically reduced or abolished expression. Purified LPG or phosphoglycan, the delipidated form of the LPG molecule, was also shown to bind to a variety of different cell types in a temperature-independent manner. Since LPG has been implicated as having an immunoprotective role in leishmaniasis, these results suggest a further mechanism(s) by which Leishmania LPG might be involved in parasite pathogenicity and virulence. PMID:1699895

  19. Increased expression of surface CD44 in hypoxia-DCs skews helper T cells toward a Th2 polarization

    PubMed Central

    Yang, Meixiang; Liu, Yanguo; Ren, Guangwen; Shao, Qianqian; Gao, Wenjuan; Sun, Jintang; Wang, Huayang; Ji, Chunyan; Li, Xingang; Zhang, Yun; Qu, Xun

    2015-01-01

    A low partial oxygen pressure (hypoxia) occurs in many pathological environments, such as solid tumors and inflammatory lesions. Understanding the cellular response to hypoxic stress has broad implications for human diseases. As we previously reported, hypoxia significantly altered dendritic cells (DCs) to a DC2 phenotype and promoted a Th2 polarization of naïve T cells with increased IL-4 production. However, the underlying mechanisms still remain largely unknown. In this study, we found the over-expression of surface CD44 in DCs was involved in this process via ligand binding. Further investigation showed hypoxia could reduce the surface expression of membrane type 1 metalloprotease (MT1-MMP) via down-regulating the kinesin-like protein KIF2A, which subsequently alleviated the shedding of CD44 from DCs. Moreover, KIF2A expression was found negatively regulated by HIF-1α in hypoxic microenvironment. These results suggest a previously uncharacterized mechanism by which hypoxia regulates the function of DCs via KIF2A/MT1-MMP/CD44 axis, providing critical information to understand the immune response under hypoxia. PMID:26323509

  20. Mesenchymal Stromal Cells Express GARP/LRRC32 on Their Surface: Effects on Their Biology and Immunomodulatory Capacity

    PubMed Central

    Carrillo-Galvez, Ana Belén; Cobo, Marién; Cuevas-Ocaña, Sara; Gutiérrez-Guerrero, Alejandra; Sánchez-Gilabert, Almudena; Bongarzone, Pierpaolo; García-Pérez, Angélica; Muñoz, Pilar; Benabdellah, Karim; Toscano, Miguel G; Martín, Francisco; Anderson, Per

    2015-01-01

    Mesenchymal stromal cells (MSCs) represent a promising tool for therapy in regenerative medicine, transplantation, and autoimmune disease due to their trophic and immunomodulatory activities. However, we are still far from understanding the mechanisms of action of MSCs in these processes. Transforming growth factor (TGF)-β1 is a pleiotropic cytokine involved in MSC migration, differentiation, and immunomodulation. Recently, glycoprotein A repetitions predominant (GARP) was shown to bind latency-associated peptide (LAP)/TGF-β1 to the cell surface of activated Foxp3+ regulatory T cells (Tregs) and megakaryocytes/platelets. In this manuscript, we show that human and mouse MSCs express GARP which presents LAP/TGF-β1 on their cell surface. Silencing GARP expression in MSCs increased their secretion and activation of TGF-β1 and reduced their proliferative capacity in a TGF-β1-independent manner. Importantly, we showed that GARP expression on MSCs contributed to their ability to inhibit T-cell responses in vitro. In summary, we have found that GARP is an essential molecule for MSC biology, regulating their immunomodulatory and proliferative activities. We envision GARP as a new target for improving the therapeutic efficacy of MSCs and also as a novel MSC marker. Stem Cells 2015;33:183–195 PMID:25182959

  1. The mycotoxin deoxynivalenol inhibits the cell surface expression of activation markers in human macrophages.

    PubMed

    Waché, Yann J; Hbabi-Haddioui, Laila; Guzylack-Piriou, Laurence; Belkhelfa, Haouaria; Roques, Christine; Oswald, Isabelle P

    2009-08-21

    Deoxynivalenol (DON) is the most prevalent trichothecene mycotoxin in crops in Europe and North America. It exhibits several toxic effects including impaired growth and immune dysregulation. Macrophages play pivotal role in the host defense; upon activation, they express several specific cell surface receptors that are important in adhesion and cell signaling. Several studies have demonstrated that DON can affect macrophages, however, very few data are available concerning the effect of DON on human macrophages, and the effect on macrophage cell surface receptors is unknown. In the present study, human blood monocytes, differentiated in vitro into macrophages, were activated with IFN-gamma, in the presence or absence of low concentrations of DON. The expression of CD11c, CD13, CD14, CD18, CD33, CD35, CD54, CD119 and HLA-DP/DQ/DR was analyzed by flow cytometry. As expected, macrophage activation by IFN-gamma upregulated the expression of CD54, CD14, CD119 and HLA-DP/DQ/DR. Incubation with DON decrease the cell surface expression of these activation markers in a dose-dependent manner. When cells were treated with 5muM DON, the mean fluorescence intensity measured for the expression of these receptors was the same as that observed in non-activated macrophages. This inhibitory effect of DON was only observed when the mycotoxin was applied before the activation signal. Taken together, our results suggest that low concentration of DON alter macrophage activation as measured by the expression of cell surface markers. This may have implications for human health when consuming DON contaminated feed. PMID:19549553

  2. Improved free-surface expression for frequency-domain elastic optimal mixed-grid modeling

    NASA Astrophysics Data System (ADS)

    Cao, Jian; Chen, Jing-Bo; Dai, Meng-Xue

    2016-07-01

    An accurate and efficient forward modeling is the foundation of full-waveform inversion (FWI). In elastic wave modeling, one of the key problems is how to deal with the free-surface boundary condition appropriately. For the representation of the free-surface boundary condition, conventional displacement-based approaches and staggered-grid approaches are often used in time-domain. In frequency-domain, considering the saving of storage and CPU time, we integrate the idea of physical parameter-modified staggered-grid approach in time-domain with an elastic optimal mixed-grid modeling scheme to design an improved parameter-modified free-surface expression. Accuracy analysis shows that an elastic optimal mixed-grid modeling scheme using the parameter-modified free-surface expression can provide more accurate solutions with only 4 grid points per smallest shear wavelength than conventional displacement-based approaches and is stable for most Poisson ratios. Besides, it also yields smaller condition number of the resulting impedance matrix than conventional displacement-based approaches in laterally varying complex media. These advantages reveal great potential of this free-surface expression in big-data practical application.

  3. Regulation of Cardiac ATP-sensitive Potassium Channel Surface Expression by Calcium/Calmodulin-dependent Protein Kinase II*

    PubMed Central

    Sierra, Ana; Zhu, Zhiyong; Sapay, Nicolas; Sharotri, Vikas; Kline, Crystal F.; Luczak, Elizabeth D.; Subbotina, Ekaterina; Sivaprasadarao, Asipu; Snyder, Peter M.; Mohler, Peter J.; Anderson, Mark E.; Vivaudou, Michel; Zingman, Leonid V.; Hodgson-Zingman, Denice M.

    2013-01-01

    Cardiac ATP-sensitive potassium (KATP) channels are key sensors and effectors of the metabolic status of cardiomyocytes. Alteration in their expression impacts their effectiveness in maintaining cellular energy homeostasis and resistance to injury. We sought to determine how activation of calcium/calmodulin-dependent protein kinase II (CaMKII), a central regulator of calcium signaling, translates into reduced membrane expression and current capacity of cardiac KATP channels. We used real-time monitoring of KATP channel current density, immunohistochemistry, and biotinylation studies in isolated hearts and cardiomyocytes from wild-type and transgenic mice as well as HEK cells expressing wild-type and mutant KATP channel subunits to track the dynamics of KATP channel surface expression. Results showed that activation of CaMKII triggered dynamin-dependent internalization of KATP channels. This process required phosphorylation of threonine at 180 and 224 and an intact 330YSKF333 endocytosis motif of the KATP channel Kir6.2 pore-forming subunit. A molecular model of the μ2 subunit of the endocytosis adaptor protein, AP2, complexed with Kir6.2 predicted that μ2 docks by interaction with 330YSKF333 and Thr-180 on one and Thr-224 on the adjacent Kir6.2 subunit. Phosphorylation of Thr-180 and Thr-224 would favor interactions with the corresponding arginine- and lysine-rich loops on μ2. We concluded that calcium-dependent activation of CaMKII results in phosphorylation of Kir6.2, which promotes endocytosis of cardiac KATP channel subunits. This mechanism couples the surface expression of cardiac KATP channels with calcium signaling and reveals new targets to improve cardiac energy efficiency and stress resistance. PMID:23223335

  4. The O-Antigen Capsule of Salmonella enterica Serovar Typhimurium Facilitates Serum Resistance and Surface Expression of FliC

    PubMed Central

    Marshall, Joanna M.

    2015-01-01

    Group IV polysaccharide capsules are common in enteric bacteria and have more recently been described in nontyphoidal Salmonella species. Such capsules are known as O-antigen (O-Ag) capsules, due to their high degree of similarity to the O-Ag of the lipopolysaccharide (LPSO-Ag). Capsular polysaccharides are known virulence factors of many bacterial pathogens, facilitating evasion of immune recognition and systemic dissemination within the host. Previous studies on the O-Ag capsule of salmonellae have focused primarily on its role in bacterial surface attachment and chronic infection; however, the potential effects of the O-Ag capsule on acute pathogenesis have yet to be investigated. While much of the in vivo innate immune resistance of Salmonella enterica serovar Typhimurium is attributed to the high-molecular-weight LPS, we hypothesized that the O-Ag capsule may enhance this resistance by diminishing surface expression of pathogen-associated molecular patterns, such as flagella, and increasing resistance to host immune molecules. To test this hypothesis, O-Ag capsule-deficient mutants were constructed, and the loss of O-Ag capsular surface expression was confirmed through microscopy and immunoblotting. Loss of O-Ag capsule production did not alter bacterial growth or production of LPS. Western blot analysis and confocal microscopy revealed that O-Ag capsule-deficient mutants demonstrate reduced resistance to killing by human serum. Furthermore, O-Ag capsule-deficient mutants produced exclusively phase I flagellin (FliC). Although O-Ag capsule-deficient mutants did not exhibit reduced virulence in a murine model of acute infection, in vitro results indicate that the O-Ag capsule may function to modify the antigenic nature of the bacterial surface, warranting additional investigation of a potential role of the structure in pathogenesis. PMID:26195553

  5. EGCG decreases binding of calcium oxalate monohydrate crystals onto renal tubular cells via decreased surface expression of alpha-enolase.

    PubMed

    Kanlaya, Rattiyaporn; Singhto, Nilubon; Thongboonkerd, Visith

    2016-06-01

    Crystal retention on tubular cell surface inside renal tubules is considered as the earliest and crucial step for kidney stone formation. Therapeutics targeting this step would cease the development of kidney stone. This study thus aimed to investigate the potential role of epigallocatechin-3-gallate (EGCG), a major antioxidant found in green tea leaves, in the reduction of calcium oxalate monohydrate (COM) crystal binding onto renal tubular cells. Pretreatment of the cells with EGCG for up to 6 h significantly diminished crystal-binding capability in a dose-dependent manner. Indirect immunofluorescence assay without and with cell permeabilization followed by laser-scanning confocal microscopy revealed that EGCG significantly reduced surface expression of alpha-enolase, whereas its intracellular level was increased. Western blot analysis confirmed such contradictory changes in membrane and cytosolic fractions of EGCG-treated cells, whereas the total level in whole cell lysate remained unchanged. Moreover, overexpression of surface alpha-enolase and enhancement of cell-crystal adhesion induced by 10 mM sodium oxalate were completely abolished by EGCG. Taken together, these data indicate that EGCG decreases binding of COM crystals onto renal tubular cells by decreasing the surface expression of alpha-enolase via re-localization or inhibition of alpha-enolase shuttling from the cytoplasm to the plasma membrane. These findings may also explain the effects of EGCG in reducing COM crystal deposition in previous animal models of kidney stone disease. Thus, EGCG may be useful for the prevention of new or recurrent stone formation. PMID:26898643

  6. Patterned CoCrMo and Al2 O3 surfaces for reduced free wear debris in artificial joint arthroplasty.

    PubMed

    Tarabolsi, Mohamad; Klassen, Thomas; Mantwill, Frank; Gärtner, Frank; Siegel, Frank; Schulz, Arndt-Peter

    2013-12-01

    Surface wear of corresponding tribological pairings is still a major problem in the application of artificial joint surgery. This study aims at developing wear reduced surfaces to utilize them in total joint arthroplasty. Using a pico-second laser, samples of medical CoCrMo metal alloy and Al2 O3 ceramic were patterned by laser material removal. The subsequent tribological investigations employed a ring-on-disc method. The results showed that those samples with modified surfaces show less mass or volume loss than those with a regular, smooth surface. Using calf serum as lubricating medium, the volume loss of the structured CoCrMo samples was eight times lower than that of regular samples. By structuring Al2 O3 surfaces, the wear volume could be reduced by 4.5 times. The results demonstrate that defined surface channels or pits enable the local sedimentation of wear debris. Thus, the amount of free debris could be reduced. Fewer abrasives in the lubricated so-called three-body-wear between the contact surfaces should result in less surface damage. Apart from direct influences on the wear behavior, less amounts of free debris of artificial joints should also be beneficial for avoiding undesired reactions with the surrounding soft tissues. The results from this study are very promising. Future investigations should involve the use of simulators meeting the natural conditions in the joint and in vivo studies with living organisms. PMID:23595908

  7. Liver-specific expression of carboxylesterase 1g/esterase-x reduces hepatic steatosis, counteracts dyslipidemia and improves insulin signaling.

    PubMed

    Bahitham, Wesam; Watts, Russell; Nelson, Randal; Lian, Jihong; Lehner, Richard

    2016-05-01

    Ces1g/Es-x deficiency in mice results in weight gain, insulin resistance, fatty liver and hyperlipidemia through upregulation of de novo lipogenesis and oversecretion of triacylglycerol (TG)-rich lipoproteins. Here, we show that restoration of Ces1g/Es-x expression only in the liver significantly reduced hepatic TG concentration accompanied by decreased size of lipid droplets, reduced secretion of very low-density lipoproteins and improved insulin-mediated signal transduction in the liver. Collectively, these results demonstrate that hepatic Ces1g/Es-x plays a critical role in limiting hepatic steatosis, very low-density lipoprotein assembly and in augmenting insulin sensitivity. PMID:26976727

  8. Reduced glycine transporter type 1 expression leads to major changes in glutamatergic neurotransmission of CA1 hippocampal neurones in mice

    PubMed Central

    Martina, Marzia; Turcotte, Marie-Eve B; Halman, Samantha; Tsai, Guochuan; Tiberi, Mario; Coyle, Joseph T; Bergeron, Richard

    2005-01-01

    To investigate the effects of persistent elevation of synaptic glycine at Schaffer collateral–CA1 synapses of the hippocampus, we studied the glutamatergic synaptic transmission in acute brain slices from mice with reduced expression of glycine transporter type 1 (GlyT1+/−) as compared to wild type (WT) littermates using whole-cell patch-clamp recordings of CA1 pyramidal cells. We observed faster decay kinetics, reduced ifenprodil sensitivity and increased zinc-induced antagonism in N-methyl-d-aspartate receptor (NMDAR) currents of GlyT1+/− mice. Moreover, the ratio α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR)/NMDAR was decreased in mutants compared to WT. Surprisingly, this change was associated with a reduction in the number of AMPARs expressed at the CA1 synapses in the mutants compared to WT. Overall, these findings highlight the importance of GlyT1 in regulating glutamatergic neurotransmission. PMID:15661817

  9. Purification, characterization, cloning, and expression of a novel xyloglucan-specific glycosidase, oligoxyloglucan reducing end-specific cellobiohydrolase.

    PubMed

    Yaoi, Katsuro; Mitsuishi, Yasushi

    2002-12-13

    A novel oligoxyloglucan-specific glycosidase, oligoxyloglucan reducing end-specific cellobiohydrolase (OXG-RCBH), with a molecular mass of 97 kDa and a pI of 6.1, was isolated from the fungus Geotrichum sp. M128. Analysis of substrate specificity using various xyloglucan oligosaccharide structures revealed that OXG-RCBH had exoglucanase activity. It recognized the reducing end of oligoxyloglucan and released two glucosyl residue segments from the main chain. The full-length cDNA encoding OXG-RCBH was cloned and sequenced, and it had a 2436-bp open reading frame encoding an 812amino acid protein. The deduced protein showed approximately 35% identity to members of glycoside hydrolase family 74. The cDNA encoding OXG-RCBH was then expressed in Escherichia coli. Although the recombinant protein was expressed as an inclusion body, renaturation was successful, and enzymatically active recombinant OXG-RCBH was obtained. PMID:12374797

  10. Reduced sensitivity to both positive and negative reinforcement in mice over-expressing the 5-hydroxytryptamine transporter.

    PubMed

    Line, Samantha J; Barkus, Chris; Rawlings, Nancy; Jennings, Katie; McHugh, Stephen; Sharp, Trevor; Bannerman, David M

    2014-12-01

    The 5-hydroxytryptamine (5-HT) transporter (5-HTT) is believed to play a key role in both normal and pathological psychological states. Much previous data suggest that the s allele of the polymorphic regulatory region of the 5-HTT gene promoter is associated with reduced 5-HTT expression and vulnerability to psychiatric disorders, including anxiety and depression. In comparison, the l allele, which increases 5-HTT expression, is generally considered protective. However, recent data link this allele to both abnormal 5-HT signalling and psychopathic traits. Here, we studied the processing of aversive and rewarding cues in transgenic mice that over-express the 5-HTT (5-HTTOE mice). Compared with wild-type mice, 5-HTTOE mice froze less in response to both a tone that had previously been paired with footshock, and the conditioning context. In addition, on a decision-making T-maze task, 5-HTTOE mice displayed reduced preference for a larger, delayed reward and increased preference for a smaller, immediate reward, suggesting increased impulsiveness compared with wild-type mice. However, further inspection of the data revealed that 5-HTTOE mice displayed a relative insensitivity to reward magnitude, irrespective of delay. In contrast, 5-HTTOE mice appeared normal on tests of spatial working and reference memory, which required an absolute choice between options associated with either reward or no reward. Overall, the present findings suggest that 5-HTT over-expression results in a reduced sensitivity to both positive and negative reinforcers. Thus, these data show that increased 5-HTT expression has some maladaptive effects, supporting recent suggestions that l allele homozygosity may be a potential risk factor for disabling psychiatric traits. PMID:25283165

  11. Expressing ScACR3 in rice enhanced arsenite efflux and reduced arsenic accumulation in rice grains.

    PubMed

    Duan, Guilan; Kamiya, Takehiro; Ishikawa, Satoru; Arao, Tomohito; Fujiwara, Toru

    2012-01-01

    Arsenic (As) accumulation in rice grain poses a serious health risk to populations with high rice consumption. Extrusion of arsenite [As(III)] by ScAcr3p is the major arsenic detoxification mechanism in Saccharomyces cerevisiae. However, ScAcr3p homolog is absent in higher plants, including rice. In this study, ScACR3 was introduced into rice and expressed under the control of the Cauliflower mosaic virus (CaMV) 35S promoter. In the transgenic lines, As concentrations in shoots and roots were about 30% lower than in the wild type, while the As translocation factors were similar between transgenic lines and the wild type. The roots of transgenic plants exhibited significantly higher As efflux activities than those of the wild type. Within 24 h exposure to 10 μM arsenate [As(V)], roots of ScACR3-expressing plants extruded 80% of absorbed As(V) to the external solution as As(III), while roots of the wild type extruded 50% of absorbed As(V). Additionally, by exposing the As-containing rice plants to an As-lacking solution for 24 h, about 30% of the total As derived from pre-treatment was extruded to the external solution by ScACR3-expressing plants, while about 15% of As was extruded by wild-type plants. Importantly, ScACR3 expression significantly reduced As accumulation in rice straws and grains. When grown in flooded soil irrigated with As(III)-containing water, the As concentration in husk and brown rice of the transgenic lines was reduced by 30 and 20%, respectively, compared with the wild type. This study reports a potential strategy to reduce As accumulation in the food chain by expressing heterologous genes in crops. PMID:22107880

  12. Overwintering Is Associated with Reduced Expression of Immune Genes and Higher Susceptibility to Virus Infection in Honey Bees

    PubMed Central

    Steinmann, Nadja; Corona, Miguel; Neumann, Peter; Dainat, Benjamin

    2015-01-01

    The eusocial honey bee, Apis mellifera, has evolved remarkable abilities to survive extreme seasonal differences in temperature and availability of resources by dividing the worker caste into two groups that differ in physiology and lifespan: summer and winter bees. Most of the recent major losses of managed honey bee colonies occur during the winter, suggesting that winter bees may have compromised immune function and higher susceptibility to diseases. We tested this hypothesis by comparing the expression of eight immune genes and naturally occurring infection levels of deformed wing virus (DWV), one of the most widespread viruses in A. mellifera populations, between summer and winter bees. Possible interactions between immune response and physiological activity were tested by measuring the expression of vitellogenin and methyl farnesoate epoxidase, a gene coding for the last enzyme involved in juvenile hormone biosynthesis. Our data show that high DWV loads in winter bees correlate with reduced expression of genes involved in the cellular immune response and physiological activity and high expression of humoral immune genes involved in antibacterial defense compared with summer bees. This expression pattern could reflect evolutionary adaptations to resist bacterial pathogens and economize energy during the winter under a pathogen landscape with reduced risk of pathogenic viral infections. The outbreak of Varroa destructor infestation could have overcome these adaptations by promoting the transmission of viruses. Our results suggest that reduced cellular immune function during the winter may have increased honey bee’s susceptibility to DWV. These results contribute to our understanding of honey bee colony losses in temperate regions. PMID:26121358

  13. Overwintering Is Associated with Reduced Expression of Immune Genes and Higher Susceptibility to Virus Infection in Honey Bees.

    PubMed

    Steinmann, Nadja; Corona, Miguel; Neumann, Peter; Dainat, Benjamin

    2015-01-01

    The eusocial honey bee, Apis mellifera, has evolved remarkable abilities to survive extreme seasonal differences in temperature and availability of resources by dividing the worker caste into two groups that differ in physiology and lifespan: summer and winter bees. Most of the recent major losses of managed honey bee colonies occur during the winter, suggesting that winter bees may have compromised immune function and higher susceptibility to diseases. We tested this hypothesis by comparing the expression of eight immune genes and naturally occurring infection levels of deformed wing virus (DWV), one of the most widespread viruses in A. mellifera populations, between summer and winter bees. Possible interactions between immune response and physiological activity were tested by measuring the expression of vitellogenin and methyl farnesoate epoxidase, a gene coding for the last enzyme involved in juvenile hormone biosynthesis. Our data show that high DWV loads in winter bees correlate with reduced expression of genes involved in the cellular immune response and physiological activity and high expression of humoral immune genes involved in antibacterial defense compared with summer bees. This expression pattern could reflect evolutionary adaptations to resist bacterial pathogens and economize energy during the winter under a pathogen landscape with reduced risk of pathogenic viral infections. The outbreak of Varroa destructor infestation could have overcome these adaptations by promoting the transmission of viruses. Our results suggest that reduced cellular immune function during the winter may have increased honey bee's susceptibility to DWV. These results contribute to our understanding of honey bee colony losses in temperate regions. PMID:26121358

  14. Electroacupuncture Reduces Aβ Production and BACE1 Expression in SAMP8 Mice

    PubMed Central

    Dong, Wei-Guo; Wang, Feng; Chen, Ye; Zheng, Xue-Hua; Xie, Yong-Cai; Guo, Wan-Qing; Shi, Hong

    2015-01-01

    Electroacupuncture (EA) has been reported to have beneficial effects on Alzheimer’s disease (AD). BACE1 (β-site amyloid precursor protein-cleaving enzyme 1) is involved in the abnormal production of amyloid-β plaque (Aβ), a hallmark of AD pathophysiology. Thus, the present study investigated the effects of EA on memory impairment, Aβ production, and BACE1 expression in senescence-accelerated mouse prone 8 (SAMP8) mice. We found that EA improved spatial learning and memory impairment of SAMP8 mice. Furthermore, EA attenuated Aβ production and repressed the expression of BACE1 in the hippocampus of SAMP8 mice. Taken together, our results suggest that EA could have a potential therapeutic application in AD and that BACE1 may be an important target of EA in the treatment of AD. PMID:26283960

  15. Per a 10 protease activity modulates CD40 expression on dendritic cell surface by nuclear factor-kappaB pathway

    PubMed Central

    Goel, C; Kalra, N; Dwarakanath, B S; Gaur, S N; Arora, N

    2015-01-01

    Serine protease activity of Per a 10 from Periplaneta americana modulates dendritic cell (DC) functions by a mechanism(s) that remains unclear. In the present study, Per a 10 protease activity on CD40 expression and downstream signalling was evaluated in DCs. Monocyte-derived DCs from cockroach-allergic patients were treated with proteolytically active/heat-inactivated Per a 10. Stimulation with active Per a 10 demonstrated low CD40 expression on DCs surface (P < 0·05), while enhanced soluble CD40 level in the culture supernatant (P < 0·05) compared to the heat-inactivated Per a 10, suggesting cleavage of CD40. Per a 10 activity reduced the interleukin (IL)-12 and interferon (IFN)-γ secretion by DCs (P < 0·05) compared to heat-inactivated Per a 10, indicating that low CD40 expression is associated with low levels of IL-12 secretion. Active Per a 10 stimulation caused low nuclear factor-kappa B (NF-κB) activation in DCs compared to heat-inactivated Per a 10. Inhibition of the NF-κB pathway suppressed the CD40 expression and IL-12 secretion by DCs, further indicating that NF-κB is required for CD40 up-regulation. CD40 expression activated the tumour necrosis factor (TNF) receptor-associated factor 6 (TRAF6), thereby suggesting its involvement in NF-κB activation. Protease activity of Per a 10 induced p38 mitogen-activated protein kinase (MAPK) activation that showed no significant effect on CD40 expression by DCs. However, inhibiting p38 MAPK or NF-κB suppressed the secretion of IL-12, IFN-γ, IL-6 and TNF-α by DCs. Such DCs further reduced the secretion of IL-4, IL-6, IL-12 and TNF-α by CD4+ T cells. In conclusion, protease activity of Per a 10 reduces CD40 expression on DCs. CD40 down-regulation leads to low NF-κB levels, thereby modulating DC-mediated immune responses. PMID:25492061

  16. Biosynthetic Pathway of the Reduced Polyketide Product Citreoviridin in Aspergillus terreus var. aureus Revealed by Heterologous Expression in Aspergillus nidulans.

    PubMed

    Lin, Tzu-Shyang; Chiang, Yi-Ming; Wang, Clay C C

    2016-03-18

    Citreoviridin (1) belongs to a class of F1-ATPase β-subunit inhibitors that are synthesized by highly reducing polyketide synthases. These potent mycotoxins share an α-pyrone polyene structure, and they include aurovertin, verrucosidin, and asteltoxin. The identification of the citreoviridin biosynthetic gene cluster in Aspergillus terreus var. aureus and its reconstitution using heterologous expression in Aspergillus nidulans are reported. Two intermediates were isolated that allowed the proposal of the biosynthetic pathway of citreoviridin. PMID:26954888

  17. Mice expressing markedly reduced striatal dopamine transporters exhibit increased locomotor activity, dopamine uptake turnover rate, and cocaine responsiveness.

    PubMed

    Rao, Anjali; Sorkin, Alexander; Zahniser, Nancy R

    2013-10-01

    Variations in the expression levels of the dopamine transporter (DAT) can influence responsiveness to psychostimulant drugs like cocaine. To better understand this relationship, we studied a new DAT-low expresser (DAT-LE) mouse model and performed behavioral and biochemical studies with it. Immunoblotting and [(3) H]WIN 35,428 binding analyses revealed that these mice express ∼35% of wildtype (WT) mouse striatal DAT levels. Compared to WT mice, DAT-LE mice were hyperactive in a novel open-field environment. Despite their higher basal locomotor activity, cocaine (10 or 20 mg/kg, i.p.) induced greater locomotor activation in DAT-LE mice than in WT mice. The maximal velocity (Vmax ) of DAT-mediated [(3) H]DA uptake into striatal synaptosomes was reduced by 46% in DAT-LE mice, as compared to WT. Overall, considering the reduced number of DAT binding sites (Bmax ) along with the reduced Vmax in DAT-LE mice, a 2-fold increase in DA uptake turnover rate (Vmax /Bmax ) was found, relative to WT mice. This suggests that neuroadaptive changes have occurred in the DAT-LE mice that would help to compensate for their low DAT numbers. Interestingly, these changes do not include a reduction in tyrosine hydroxylase levels, as was previously reported in DAT knockout homozygous and heterozygous animals. Further, these changes are not sufficient to prevent elevated novelty- and cocaine-induced locomotor activity. Hence, these mice represent a unique model for studying changes of in vivo DAT function and regulation that result from markedly reduced levels of DAT expression. PMID:23564231

  18. Liver-specific transgenic expression of cholesteryl ester hydrolase reduces atherosclerosis in Ldlr-/- mice.

    PubMed

    Bie, Jinghua; Wang, Jing; Yuan, Quan; Kakiyama, Genta; Ghosh, Siddhartha S; Ghosh, Shobha

    2014-04-01

    The liver plays a central role in the final elimination of cholesterol from the body either as bile acids or as free cholesterol (FC), and lipoprotein-derived cholesterol is the major source of total biliary cholesterol. HDL is the major lipoprotein responsible for removal and transport of cholesterol, mainly as cholesteryl esters (CEs), from the peripheral tissues to the liver. While HDL-FC is rapidly secreted into bile, the fate of HDL-CE remains unclear. We have earlier demonstrated the role of human CE hydrolase (CEH, CES1) in hepatic hydrolysis of HDL-CE and increasing bile acid synthesis, a process dependent on scavenger receptor BI expression. In the present study, we examined the hypothesis that by enhancing the elimination of HDL-CE into bile/feces, liver-specific transgenic expression of CEH will be anti-atherogenic. Increased CEH expression in the liver significantly increased the flux of HDL-CE to bile acids. In the LDLR(-/-) background, this enhanced elimination of cholesterol led to attenuation of diet-induced atherosclerosis with a consistent increase in fecal sterol secretion primarily as bile acids. Taken together with the observed reduction in atherosclerosis by increasing macrophage CEH-mediated cholesterol efflux, these studies establish CEH as an important regulator in enhancing cholesterol elimination and also as an anti-atherogenic target. PMID:24563511

  19. Polyphenols from Chilean Propolis and Pinocembrin Reduce MMP-9 Gene Expression and Activity in Activated Macrophages

    PubMed Central

    Saavedra, Nicolás; Cuevas, Alejandro; Cavalcante, Marcela F.; Dörr, Felipe A.; Saavedra, Kathleen; Zambrano, Tomás; Abdalla, Dulcineia S. P.; Salazar, Luis A.

    2016-01-01

    Polyphenols from diverse sources have shown anti-inflammatory activity. In the context of atherosclerosis, macrophages play important roles including matrix metalloproteinases synthesis involved in degradation of matrix extracellular components affecting the atherosclerotic plaque stability. We prepared a propolis extract and pinocembrin in ethanol solution. Propolis extract was chemically characterized using LC-MS. The effect of treatments on gene expression and proteolytic activity was measured in vitro using murine macrophages activated with LPS. Cellular toxicity associated with both treatments and the vehicle was determined using MTT and apoptosis/necrosis detection assays. MMP-9 gene expression and proteolytic activity were measured using qPCR and zymography, respectively. Thirty-two compounds were identified in the propolis extract, including pinocembrin among its major components. Treatment with either ethanolic extract of propolis or pinocembrin inhibits MMP-9 gene expression in a dose-dependent manner. Similarly, an inhibitory effect was observed in proteolytic activity. However, the effect showed by ethanolic extract of propolis was higher than the effect of pinocembrin, suggesting that MMP-9 inhibition results from a joint contribution between the components of the extract. These data suggest a potential role of polyphenols from Chilean propolis in the control of extracellular matrix degradation in atherosclerotic plaques. PMID:27119082

  20. Reduced frequency of T lymphocytes expressing CTLA-4 in frontotemporal dementia compared to Alzheimer's disease.

    PubMed

    Santos, Rodrigo Ribeiro; Torres, Karen C; Lima, Giselle S; Fiamoncini, Carolina M; Mapa, Filipe C; Pereira, Patricia A; Rezende, Vitor B; Martins, Luiza C; Bicalho, Maria A; Moraes, Edgar N; Reis, Helton J; Teixeira, Antonio L; Romano-Silva, Marco A

    2014-01-01

    Studies suggest that inflammation is involved in the neurodegenerative cascade of dementias. Immunological mechanisms may be part of the pathophysiological process in frontotemporal dementia (FTD), but up till now only vague evidence of such mechanisms has been presented. The B7- CD28/CTLA-4 pathway is an important immunological signaling pathway involved in modulation of T cell activation. The aim of this study was to compare the expression of molecules associated with co-stimulatory signaling in peripheral blood mononuclear cells (PBMC) of FTD to Alzheimer disease (AD) and control groups. Our results confirm the previous demonstrated increased expression of CD80 in CD14+ Alzheimer patients T cells but show, for the first time, a reduction in the expression of CTLA-4 in CD4+ FTD cells. As CTLA-4 is the most potent negative regulators of T-cell activation we speculated that peripheral T lymphocytes in FTD are more activated and this could be involved in the neurodegeneration observed in this dementia. PMID:23891730

  1. Reducing Ventral Tegmental Dopamine D2 Receptor Expression Selectively Boosts Incentive Motivation

    PubMed Central

    de Jong, Johannes W; Roelofs, Theresia J M; Mol, Frédérique M U; Hillen, Anne E J; Meijboom, Katharina E; Luijendijk, Mieneke C M; van der Eerden, Harrie A M; Garner, Keith M; Vanderschuren, Louk J M J; Adan, Roger A H

    2015-01-01

    Altered mesolimbic dopamine signaling has been widely implicated in addictive behavior. For the most part, this work has focused on dopamine within the striatum, but there is emerging evidence for a role of the auto-inhibitory, somatodendritic dopamine D2 receptor (D2R) in the ventral tegmental area (VTA) in addiction. Thus, decreased midbrain D2R expression has been implicated in addiction in humans. Moreover, knockout of the gene encoding the D2R receptor (Drd2) in dopamine neurons has been shown to enhance the locomotor response to cocaine in mice. Therefore, we here tested the hypothesis that decreasing D2R expression in the VTA of adult rats, using shRNA knockdown, promotes addiction-like behavior in rats responding for cocaine or palatable food. Rats with decreased VTA D2R expression showed markedly increased motivation for both sucrose and cocaine under a progressive ratio schedule of reinforcement, but the acquisition or maintenance of cocaine self-administration were not affected. They also displayed enhanced cocaine-induced locomotor activity, but no change in basal locomotion. This robust increase in incentive motivation was behaviorally specific, as we did not observe any differences in fixed ratio responding, extinction responding, reinstatement or conditioned suppression of cocaine, and sucrose seeking. We conclude that VTA D2R knockdown results in increased incentive motivation, but does not directly promote other aspects of addiction-like behavior. PMID:25735756

  2. Simulation and preparation of surface EVA in reduced gravity at the Marseilles Bay subsea analogue sites

    NASA Astrophysics Data System (ADS)

    Weiss, P.; Gardette, B.; Chirié, B.; Collina-Girard, J.; Delauze, H. G.

    2012-12-01

    Extravehicular activity (EVA) of astronauts during space missions is simulated nowadays underwater in neutral buoyancy facilities. Certain aspects of weightlessness can be reproduced underwater by adding buoyancy to a diver-astronaut, therefore exposing the subject to the difficulties of working without gravity. Such tests were done at the COMEX' test pool in Marseilles in the 1980s to train for a French-Russian mission to the MIR station, for the development of the European HERMES shuttle and the COLUMBUS laboratory. However, space agencies are currently studying missions to other destinations than the International Space Station in orbit, such as the return to the Moon, NEO (near-Earth objects) or Mars. All these objects expose different gravities: Moon has one sixth of Earth's gravity, Mars has a third of Earth's gravity and asteroids have virtually no surface gravity; the astronaut "floats" above the ground. The preparation of such missions calls for a new concept in neutral buoyancy training, not on man-made structures, but on natural terrain, underwater, to simulate EVA operations such as sampling, locomotion or even anchoring in low gravity. Underwater sites can be used not only to simulate the reduced gravity that astronauts will experience during their field trips, also human factors like stress are more realistically reproduced in such environment. The Bay of Marseille hosts several underwater sites that can be used to simulate various geologic morphologies, such as sink-holes which can be used to simulate astronaut descends into craters, caves where explorations of lava tubes can be trained or monolithic rock structures that can be used to test anchoring devices (e.g., near Earth objects). Marseilles with its aerospace and maritime/offshore heritage hosts the necessary logistics and expertise that is needed to perform such simulations underwater in a safe manner (training of astronaut-divers in local test pools, research vessels, subsea robots and

  3. The effect of surface characteristics of reduced graphene oxide on the performance of a pseudocapacitor

    NASA Astrophysics Data System (ADS)

    Chang, M. S.; Kim, T.; Kang, J. H.; Park, J.; Park, C. R.

    2015-03-01

    In this research, we have analyzed the electrochemical characteristics of the different rGO/Co3O4 composites prepared by controlling the rGO surface characteristics and its relationship between the growth of Co3O4 nanoparticles and the performance of the pseudocapacitor. Reduced graphene oxide/cobalt oxide (rGO/Co3O4) nanocomposites of different morphologies were prepared through the simple hydrothermal method. First, different kinds of graphite precursors, crumpled and planar with different properties, were used to determine the most suitable substrate to grow Co3O4 nanoparticles. As a result, rGO/Co3O4 composite synthesized from planar graphite shows a higher specific capacitance of 207.2, 170.1, and 141.5 Fg-1 at 1, 2, and 5 Ag-1 than the one prepared from crumpled graphite. In the second part, planar graphite, confirmed to be the most suitable substrate from the previous part, was oxidized under various oxidation conditions to increase the oxygen functional groups attached on the GO surfaces and observed to see how it affects the growth of Co3O4 nanoparticles and its influence on the electrochemical performance of the rGO/Co3O4 pseudocapacitor. As a result, the one with the largest amount of functional groups had the Co3O4 nanoparticles well dispersed and grown on the rGO substrate in small nanoparticle sizes, as small as 5.9 nm, leading to an improved electrochemical performance. Thus, the specific capacitance with the least amount of oxygen functional groups are 207.2, 170.1, and 141.5 Fg-1 and for the largest amount of functional groups are 411.5, 371.4, and 292.7 Fg-1, at 1, 2, and 5 Ag-1 respectively. This approach could become a guideline for the ideal fabrication of rGO/metal oxide composite for further research involving rGO based pseudocapacitors.

  4. Reduced Surface Ocean Temperature Variability in the Eastern Equatorial Pacific During the Late Glacial Maximum

    NASA Astrophysics Data System (ADS)

    Ford, H. L.; Ravelo, A. C.; Polissar, P. J.

    2012-12-01

    El Niño-Southern Oscillation is the largest source of global interannual variability with far-reaching climatic effects. Climate model simulations of future warming exhibit widely divergent behavior indicating an incomplete understanding of the factors that dictate tropical climate variability. Generating records of past tropical Pacific variability during times with different climate states is one approach to deepening our understanding of tropical climate change processes and improving predictions of future change. Here we reconstruct tropical Pacific ocean variability from the Last Glacial Maximum (LGM) and from the Holocene at ODP Sites 806 and 849, located in the western equatorial Pacific (WEP) warm pool and eastern equatorial Pacific (EEP) cold tongue, respectively. We reconstruct ocean temperature variability using the intra-sample distribution of Mg/Ca values from individual foraminifera. Sea surface temperature variability is reconstructed from individual specimens of G. sacculifer analyzed for Mg/Ca values with laser ablation ICP-MS (Photon Machines Analyte.193 with HelEx sample cell coupled with a Thermo ElementXS ICP-MS, LA-ICP-MS). Subsurface temperature variability is reconstructed from individual specimens of G. tumida analyzed for Mg/Ca values by ICP-OES. Our results indicate that the cooling of last glacial maximum SSTs was greater in the WEP compared to the EEP. Furthermore, we show this cooling is not an artifact of changes in seasonal or interannual foraminiferal fluxes, but rather, reflects overall cooler temperatures and thus changes in seasonal/interannual heat fluxes. At Site 806 in the WEP, variability during the Holocene and LGM was similar, suggesting the cooling was a direct response to pCO2-radiative forcing. In contrast, at Site 849, sea surface temperature variability during the LGM was greatly diminished in comparison to the Holocene suggesting reduced ENSO and seasonal variability. Therefore conditions in the EEP responded to both

  5. Protostylid expression at the enamel-dentine junction and enamel surface of mandibular molars of Paranthropus robustus and Australopithecus africanus.

    PubMed

    Skinner, Matthew M; Wood, Bernard A; Hublin, Jean-Jacques

    2009-01-01

    Distinctive expressions and incidences of discrete dental traits at the outer enamel surface (OES) contribute to the diagnoses of many early hominin taxa. Examination of the enamel-dentine junction (EDJ), imaged non-destructively using micro-computed tomography, has elucidated the morphological development of dental traits and improved interpretations of their variability within and among taxa. The OES expressions of one of these dental traits, the protostylid, have been found to differ among African Plio-Pleistocene fossil hominin taxa. In this study protostylid expression is examined at the OES and at the EDJ of Paranthropus robustus (n=23) and Australopithecus africanus (n=28) mandibular molars, with the goals of incorporating EDJ morphology into the definition of the protostylid and assessing the relative contribution of the EDJ and enamel cap to its expression in these taxa. The results provide evidence (a) of statistically significant taxon-specific patterns of protostylid morphology at the EDJ that are not evident at the OES; (b) that in P. robustus, thick enamel reduces the morphological correspondence between the form of the protostylid seen at the EDJ and the OES, and (c) that if EDJ images can be obtained, then the protostylid retains its taxonomic value even in worn teeth. PMID:18986683

  6. Metformin reduces the endotoxin-induced down-regulation of apolipoprotein E gene expression in macrophages

    SciTech Connect

    Stavri, Simona; Trusca, Violeta G.; Simionescu, Maya; Gafencu, Anca V.

    2015-05-29

    The atheroprotective role of macrophage-derived apolipoprotein E (apoE) is well known. Our previous reports demonstrated that inflammatory stress down-regulates apoE expression in macrophages, aggravating atherogenesis. Metformin, extensively used as an anti-diabetic drug, has also anti-inflammatory properties, and thus confers vascular protection. In this study, we questioned whether metformin could have an effect on apoE expression in macrophages in normal conditions or under lipopolysaccharide (LPS)-induced stress. The results showed that metformin slightly increases the apoE expression only at high doses (5–10 mM). Low doses of metformin (1–3 mM) significantly reduce the LPS down-regulatory effect on apoE expression in macrophages. Our experiments demonstrated that LPS-induced NF-κB binds to the macrophage-specific distal regulatory element of apoE gene, namely to the multienhancer 2 (ME.2) and its 5′-deletion fragments. The NF-κB binding on ME.2 and apoE promoter has a down-regulatory effect. In addition, data revealed that metformin impairs NF-κB nuclear translocation, and thus, improves the apoE levels in macrophages under inflammatory stress. The positive effect of metformin in the inflammatory states, its clinical safety and low cost, make this drug a potential adjuvant in the therapeutic strategies for atherosclerosis. - Highlights: • High doses of metformin slightly increase apoE expression in macrophages. • Low doses of metformin up-regulate apoE gene in endotoxin-stressed macrophages. • Metformin reduces the negative effect of LPS on apoE expression by NF-κB inhibition.

  7. Over-expression of miR375 reduces glucose-induced insulin secretion in Nit-1 cells.

    PubMed

    Xia, Hua-Qiang; Pan, Yi; Peng, Ju; Lu, Guang-Xiu

    2011-06-01

    MicroRNAs (miRNAs) are 19- to 25-nt fragments cleaved from 70- to 100-nt hairpin precursors. These molecules participate in essential biological processes. It was estimated that 30% of all protein-coding genes are miRNA targets. Thousands of miRNAs have already been identified in plants and animals, but little is known about their biological roles. MicroRNA375 (miR375) is highly expressed in pancreatic islets of humans and mice and regulates insulin secretion in isolated pancreatic cells. To improve our understanding of the biological roles of miR375, we constructed the plasmid pAAV-miR375 and transfected it into mouse Nit-1 cells. Real-time PCR and Northern blot analysis showed that the Nit-1 cells transfected with pAAV-miR375 over-expressed the mature miR375 compared with Nit-1 cells transfected with control plasmid or untransfected cells. The expression of myotrophin (Mtpn) decreased and insulin secretion was reduced in Nit-1 cells transfected with pAAV-miR375. In this study, we successfully established an over-expression system for miR375 and a technique to study the biological function of miRNAs by over-expression. We verified that miR375 reduced glucose-induced insulin secretion by down-regulating the expression of Mtpn in Nit-1 cells in vitro, suggesting that miR375 has potential therapeutic applications in type II diabetes. PMID:20221699

  8. Angiogenin Reduces Immune Inflammation via Inhibition of TANK-Binding Kinase 1 Expression in Human Corneal Fibroblast Cells

    PubMed Central

    Min, Kyong-Mi; Kim, Kyu-Wan; Chang, Soo-Ik

    2014-01-01

    Angiogenin (ANG) is reportedly multifunctional, with roles in angiogenesis and autoimmune diseases. This protein is involved in the innate immune system and has been implicated in several inflammatory diseases. Although ANG may be involved in the anti-inflammatory response, there is no evidence that it has direct anti-inflammatory effects. In this study we sought to determine whether ANG has an anti-inflammatory effect in human corneal fibroblasts (HCFs) exposed to media containing tumor necrosis factor-alpha (TNF-α). We found that ANG reduced the mRNA expression of interleukin-1 beta (IL-1β), -6, -8 and TNF-α receptors (TNFR) 1 and 2. In contrast, ANG increased the mRNA expression of IL-4 and -10. Protein levels of TANK-binding kinase 1 (TBK1) were reduced by ANG in HCFs treated with TNF-α. Moreover, ANG diminished the expression of IL-6 and -8 and monocyte chemotactic protein- (MCP-) 1. The protein expression of nuclear factor-κB (NF-κB) was downregulated by ANG treatment. These findings suggest that ANG suppressed the TNF-α-induced inflammatory response in HCFs through inhibition of TBK1-mediated NF-κB nuclear translocation. These novel results are likely to play a significant role in the selection of immune-mediated inflammatory therapeutic targets and may shed light on the pathogenesis of immune-mediated inflammatory diseases. PMID:24860242

  9. Reduced Tyk2 gene expression in β-cells due to natural mutation determines susceptibility to virus-induced diabetes.

    PubMed

    Izumi, Kenichi; Mine, Keiichiro; Inoue, Yoshitaka; Teshima, Miho; Ogawa, Shuichiro; Kai, Yuji; Kurafuji, Toshinobu; Hirakawa, Kanako; Miyakawa, Daiki; Ikeda, Haruka; Inada, Akari; Hara, Manami; Yamada, Hisakata; Akashi, Koichi; Niho, Yoshiyuki; Ina, Keisuke; Kobayashi, Takashi; Yoshikai, Yasunobu; Anzai, Keizo; Yamashita, Teruo; Minagawa, Hiroko; Fujimoto, Shuji; Kurisaki, Hironori; Shimoda, Kazuya; Katsuta, Hitoshi; Nagafuchi, Seiho

    2015-01-01

    Accumulating evidence suggests that viruses play an important role in the development of diabetes. Although the diabetogenic encephalomyocarditis strain D virus induces diabetes in restricted lines of inbred mice, the susceptibility genes to virus-induced diabetes have not been identified. We report here that novel Tyrosine kinase 2 (Tyk2) gene mutations are present in virus-induced diabetes-sensitive SJL and SWR mice. Mice carrying the mutant Tyk2 gene on the virus-resistant C57BL/6 background are highly sensitive to virus-induced diabetes. Tyk2 gene expression is strongly reduced in Tyk2-mutant mice, associated with low Tyk2 promoter activity, and leads to decreased expression of interferon-inducible genes, resulting in significantly compromised antiviral response. Tyk2-mutant pancreatic β-cells are unresponsive even to high dose of Type I interferon. Reversal of virus-induced diabetes could be achieved by β-cell-specific Tyk2 gene expression. Thus, reduced Tyk2 gene expression in pancreatic β-cells due to natural mutation is responsible for susceptibility to virus-induced diabetes. PMID:25849081

  10. Polyunsaturated fatty acid supplementation alters proinflammatory gene expression and reduces the incidence of necrotizing enterocolitis in a neonatal rat model.

    PubMed

    Lu, Jing; Jilling, Tamas; Li, Dan; Caplan, Michael S

    2007-04-01

    Although supplementation of preterm formula with polyunsaturated fatty acids (PUFA) has been shown to reduce the incidence of necrotizing enterocolitis (NEC) in animal models and clinical trials, the mechanisms remain elusive. We hypothesized that the protective effect of PUFA on NEC may be due to the ability of PUFA to suppress Toll-like receptor (TLR) 4 and platelet-activating factor receptor (PAFR) gene expression (molecules that are important in the pathogenesis of NEC) in epithelial cells. To investigate the efficacy of different PUFA preparations on NEC in a neonatal rat model, we compared the incidence of NEC among the four PUFA supplemented groups--A: arachidonic acid and docosahexaenoic acid (AA+DHA), B: egg phospholipids (EP), C: DHA, and D: control without PUFA. PUFA supplementation reduced the incidence of NEC and inhibited intestinal PAFR and TLR4 gene expression compared with the controls. To validate the in vivo observations, IEC-6 cells were exposed to PAF after pretreatment with AA or DHA. Both AA and DHA supplementation blocked PAF-induced TLR4 and PAFR mRNA expression in these enterocytes. These results suggest that PUFA modulates gene expression of key factors involved in experimental NEC pathogenesis. These effects might in part explain the protective effect of PUFA on neonatal NEC. PMID:17515866

  11. Reduced Tyk2 gene expression in β-cells due to natural mutation determines susceptibility to virus-induced diabetes

    PubMed Central

    Izumi, Kenichi; Mine, Keiichiro; Inoue, Yoshitaka; Teshima, Miho; Ogawa, Shuichiro; Kai, Yuji; Kurafuji, Toshinobu; Hirakawa, Kanako; Miyakawa, Daiki; Ikeda, Haruka; Inada, Akari; Hara, Manami; Yamada, Hisakata; Akashi, Koichi; Niho, Yoshiyuki; Ina, Keisuke; Kobayashi, Takashi; Yoshikai, Yasunobu; Anzai, Keizo; Yamashita, Teruo; Minagawa, Hiroko; Fujimoto, Shuji; Kurisaki, Hironori; Shimoda, Kazuya; Katsuta, Hitoshi; Nagafuchi, Seiho

    2015-01-01

    Accumulating evidence suggests that viruses play an important role in the development of diabetes. Although the diabetogenic encephalomyocarditis strain D virus induces diabetes in restricted lines of inbred mice, the susceptibility genes to virus-induced diabetes have not been identified. We report here that novel Tyrosine kinase 2 (Tyk2) gene mutations are present in virus-induced diabetes-sensitive SJL and SWR mice. Mice carrying the mutant Tyk2 gene on the virus-resistant C57BL/6 background are highly sensitive to virus-induced diabetes. Tyk2 gene expression is strongly reduced in Tyk2-mutant mice, associated with low Tyk2 promoter activity, and leads to decreased expression of interferon-inducible genes, resulting in significantly compromised antiviral response. Tyk2-mutant pancreatic β-cells are unresponsive even to high dose of Type I interferon. Reversal of virus-induced diabetes could be achieved by β-cell-specific Tyk2 gene expression. Thus, reduced Tyk2 gene expression in pancreatic β-cells due to natural mutation is responsible for susceptibility to virus-induced diabetes. PMID:25849081

  12. The development of response surface pathway design to reduce animal numbers in toxicity studies

    PubMed Central

    2014-01-01

    Background This study describes the development of Response Surface Pathway (RSP) design, assesses its performance and effectiveness in estimating LD50, and compares RSP with Up and Down Procedures (UDPs) and Random Walk (RW) design. Methods A basic 4-level RSP design was used on 36 male ICR mice given intraperitoneal doses of Yessotoxin. Simulations were performed to optimise the design. A k-adjustment factor was introduced to ensure coverage of the dose window and calculate the dose steps. Instead of using equal numbers of mice on all levels, the number of mice was increased at each design level. Additionally, the binomial outcome variable was changed to multinomial. The performance of the RSP designs and a comparison of UDPs and RW were assessed by simulations. The optimised 4-level RSP design was used on 24 female NMRI mice given Azaspiracid-1 intraperitoneally. Results The in vivo experiment with basic 4-level RSP design estimated the LD50 of Yessotoxin to be 463 μg/kgBW (95% CI: 383–535). By inclusion of the k-adjustment factor with equal or increasing numbers of mice on increasing dose levels, the estimate changed to 481 μg/kgBW (95% CI: 362–566) and 447 μg/kgBW (95% CI: 378–504 μg/kgBW), respectively. The optimised 4-level RSP estimated the LD50 to be 473 μg/kgBW (95% CI: 442–517). A similar increase in power was demonstrated using the optimised RSP design on real Azaspiracid-1 data. The simulations showed that the inclusion of the k-adjustment factor, reduction in sample size by increasing the number of mice on higher design levels and incorporation of a multinomial outcome gave estimates of the LD50 that were as good as those with the basic RSP design. Furthermore, optimised RSP design performed on just three levels reduced the number of animals from 36 to 15 without loss of information, when compared with the 4-level designs. Simulated comparison of the RSP design with UDPs and RW design demonstrated the superiority of RSP. Conclusion

  13. Reducing the Discrepancy Between ASTER and MODIS Land Surface Temperature Products

    PubMed Central

    Liu, Yuanbo; Yamaguchi, Yasushi; Ke, Changqing

    2007-01-01

    Human-induced global warming has significantly increased the importance of satellite monitoring of land surface temperature (LST) on a global scale. The MODerate-resolution Imaging Spectroradiometer (MODIS) provides a 1-km resolution LST product with almost daily coverage of the Earth, invaluable to both local and global change studies. The Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) provides a LST product with a high spatial resolution of 90-m and a 16-day recurrent cycle, simultaneously acquired at the same height and nadir view as MODIS. ASTER and MODIS are complementary in resolution, offering a unique opportunity for scale-related studies. ASTER and MODIS LST have been widely used but the errors in LST were mostly disregarded. Correction of ASTER-to-MODIS LST discrepancies is essential for studies reliant upon the joint use of these sensors. In this study, we compared three correction approaches: the Wan et al.'s approach, the refined Wan et al.'s approach, and the generalized split window (GSW) algorithm based approach. The Wan et al.'s approach corrects the MODIS 1-km LST using MODIS 5-km LST. The refined approach modifies the Wan et al.'s approach through incorporating ASTER emissivity and MODIS 5-km data. The GSW algorithm approach does not use MODIS 5-km but only ASTER emissivity data. We examined the case over a semi-arid terrain area for the part of the Loess Plateau of China. All the approaches reduced the ASTER-to-MODIS LST discrepancy effectively. With terrain correction, the original ASTER-to-MODIS LST difference reduced from 2.7±1.28 K to -0.1±1.87 K for the Wan et al.'s approach, 0.2±1.57 K for the refined approach, and 0.1±1.33 K for the GSW algorithm based approach. Among all the approaches, the GSW algorithm based approach performed best in terms of mean, standard deviation, root mean square root, and correlation coefficient.

  14. Abrogation of epithelial BMP2 and BMP4 causes Amelogenesis Imperfecta by reducing MMP20 and KLK4 expression.

    PubMed

    Xie, Xiaohua; Liu, Chao; Zhang, Hua; Jani, Priyam H; Lu, Yongbo; Wang, Xiaofang; Zhang, Bin; Qin, Chunlin

    2016-01-01

    Amelogenesis Imperfecta (AI) can be caused by the deficiencies of enamel matrix proteins, molecules responsible for the transportation and secretion of enamel matrix components, and proteases processing enamel matrix proteins. In the present study, we discovered the double deletion of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) in the dental epithelium by K14-cre resulted in hypoplastic enamel and reduced density in X-ray radiography as well as shortened enamel rods under scanning electron microscopy. Such enamel phenotype was consistent with the diagnosis of hypoplastic amelogenesis imperfecta. Histological and molecular analyses revealed that the removal of matrix proteins in the mutant enamel was drastically delayed, which was coincided with the greatly reduced expression of matrix metalloproteinase 20 (MMP20) and kallikrein 4 (KLK4). Although the expression of multiple enamel matrix proteins was down-regulated in the mutant ameloblasts, the cleavage of ameloblastin was drastically impaired. Therefore, we attributed the AI primarily to the reduction of MMP20 and KLK4. Further investigation found that BMP/Smad4 signaling pathway was down-regulated in the K14-cre;Bmp2(f/f);Bmp4(f/f)ameloblasts, suggesting that the reduced MMP20 and KLK4 expression may be due to the attenuated epithelial BMP/Smad4 signaling. PMID:27146352

  15. Increased Bacterial Load and Expression of Antimicrobial Peptides in Skin of Barrier-Deficient Mice with Reduced Cancer Susceptibility.

    PubMed

    Natsuga, Ken; Cipolat, Sara; Watt, Fiona M

    2016-01-01

    Mice lacking three epidermal barrier proteins-envoplakin, periplakin, and involucrin (EPI-/- mice)-have a defective cornified layer, reduced epidermal γδ T cells, and increased dermal CD4(+) T cells. They are also resistant to developing skin tumors. The tumor-protective mechanism involves signaling between Rae-1 expressing keratinocytes and the natural killer group 2D receptor on immune cells, which also plays a role in host defenses against infection. Given the emerging link between bacteria and cancer, we investigated whether EPI-/- mice have an altered skin microbiota. The bacterial phyla were similar in wild-type and EPI-/- skin. However, bacteria were threefold more abundant in EPI-/- skin and penetrated deeper into the epidermis. The major epithelial defense mechanism against bacteria is production of antimicrobial proteins (AMPs). EPI-/- skin exhibited enhanced expression of antimicrobial peptides. However, reducing the bacterial load by antibiotic treatment or breeding mice under specific pathogen-free conditions did not reduce AMP expression or alleviate the abnormalities in T-cell populations. We conclude that the atopic characteristics of EPI-/- skin are a consequence of the defective barrier rather than a response to the increased bacterial load. It is therefore unlikely that the increase in skin microbiota contributes directly to the observed cancer resistance. PMID:26763429

  16. Increased Bacterial Load and Expression of Antimicrobial Peptides in Skin of Barrier-Deficient Mice with Reduced Cancer Susceptibility

    PubMed Central

    Natsuga, Ken; Cipolat, Sara; Watt, Fiona M.

    2016-01-01

    Mice lacking three epidermal barrier proteins—envoplakin, periplakin, and involucrin (EPI-/- mice)—have a defective cornified layer, reduced epidermal γδ T cells, and increased dermal CD4+ T cells. They are also resistant to developing skin tumors. The tumor-protective mechanism involves signaling between Rae-1 expressing keratinocytes and the natural killer group 2D receptor on immune cells, which also plays a role in host defenses against infection. Given the emerging link between bacteria and cancer, we investigated whether EPI-/- mice have an altered skin microbiota. The bacterial phyla were similar in wild-type and EPI-/- skin. However, bacteria were threefold more abundant in EPI-/- skin and penetrated deeper into the epidermis. The major epithelial defense mechanism against bacteria is production of antimicrobial proteins (AMPs). EPI-/- skin exhibited enhanced expression of antimicrobial peptides. However, reducing the bacterial load by antibiotic treatment or breeding mice under specific pathogen-free conditions did not reduce AMP expression or alleviate the abnormalities in T-cell populations. We conclude that the atopic characteristics of EPI-/- skin are a consequence of the defective barrier rather than a response to the increased bacterial load. It is therefore unlikely that the increase in skin microbiota contributes directly to the observed cancer resistance. PMID:26763429

  17. Abrogation of epithelial BMP2 and BMP4 causes Amelogenesis Imperfecta by reducing MMP20 and KLK4 expression

    PubMed Central

    Xie, Xiaohua; Liu, Chao; Zhang, Hua; Jani, Priyam H.; Lu, Yongbo; Wang, Xiaofang; Zhang, Bin; Qin, Chunlin

    2016-01-01

    Amelogenesis Imperfecta (AI) can be caused by the deficiencies of enamel matrix proteins, molecules responsible for the transportation and secretion of enamel matrix components, and proteases processing enamel matrix proteins. In the present study, we discovered the double deletion of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) in the dental epithelium by K14-cre resulted in hypoplastic enamel and reduced density in X-ray radiography as well as shortened enamel rods under scanning electron microscopy. Such enamel phenotype was consistent with the diagnosis of hypoplastic amelogenesis imperfecta. Histological and molecular analyses revealed that the removal of matrix proteins in the mutant enamel was drastically delayed, which was coincided with the greatly reduced expression of matrix metalloproteinase 20 (MMP20) and kallikrein 4 (KLK4). Although the expression of multiple enamel matrix proteins was down-regulated in the mutant ameloblasts, the cleavage of ameloblastin was drastically impaired. Therefore, we attributed the AI primarily to the reduction of MMP20 and KLK4. Further investigation found that BMP/Smad4 signaling pathway was down-regulated in the K14-cre;Bmp2f/f;Bmp4f/fameloblasts, suggesting that the reduced MMP20 and KLK4 expression may be due to the attenuated epithelial BMP/Smad4 signaling. PMID:27146352

  18. Generation of transgenic cattle expressing human β-defensin 3 as an approach to reducing susceptibility to Mycobacterium bovis infection.

    PubMed

    Su, Feng; Wang, Yongsheng; Liu, Guanghui; Ru, Kun; Liu, Xin; Yu, Yuan; Liu, Jun; Wu, Yongyan; Quan, Fusheng; Guo, Zekun; Zhang, Yong

    2016-03-01

    Bovine tuberculosis results from infection with Mycobacterium bovis, a member of the Mycobacterium tuberculosis family. Worldwide, M. bovis infections result in economic losses in the livestock industry; cattle production is especially hard-hit by this disease. Generating M. bovis-resistant cattle may potentially mitigate the impact of this disease by reducing M. bovis infections. In this study, we used transgenic somatic cell nuclear transfer to generate cattle expressing the gene encoding human β-defensin 3 (HBD3), which confers resistance to mycobacteria in vitro. We first generated alveolar epithelial cells expressing HBD3 under the control of the bovine MUC1 promoter, and confirmed that these cells secreted HBD3 and possessed anti-mycobacterial capacity. We then generated and identified transgenic cattle by somatic cell nuclear transfer. The cleavage and blastocyst formation rates of genetically modified embryos provided evidence that monoclonal transgenic bovine fetal fibroblast cells have an integral reprogramming ability that is similar to that of normal cells. Five genetically modified cows were generated, and their anti-mycobacterial capacities were evaluated. Alveolar epithelial cells and macrophages from these cattle expressed higher levels of HBD3 protein compared with non-transgenic cells and possessed effective anti-mycobacterial capacity. These results suggest that the overall risk of M. bovis infection in transgenic cattle is efficiently reduced, and support the development of genetically modified animals as an effective tool to reduce M. bovis infection. PMID:26782926

  19. Batroxobin protects against spinal cord injury in rats by promoting the expression of vascular endothelial growth factor to reduce apoptosis

    PubMed Central

    YU, HUI; LIN, BIN; HE, YONGZHI; ZHANG, WENBIN; XU, YANG

    2015-01-01

    The host response to spinal cord injury (SCI) can lead to an ischemic environment that can induce cell death. Therapeutic interventions using neurotrophic factors have focused on the prevention of such reactions in order to reduce this cell death. Vascular endothelial growth factor (VEGF) is a potent angiogenic and vascular permeability factor. We hypothesized in this study that batroxobin would exhibit protective effects following SCI by promoting the expression of VEGF to reduce the levels of apoptosis in a rat model of SCI. Ninety adult female Sprague Dawley rats were divided randomly into sham injury (group I), SCI (group II) and batroxobin treatment (group III) groups. The Basso-Bettie-Bresnahan (BBB) scores, number of apoptotic cells and expression of VEGF were assessed at 1, 3, 5, 7, 14 and 28 days post-injury. The BBB scores were significantly improved in group III compared with those in group II between days 5 and 28 post-injury (P<0.05). At each time-point subsequent to the injury, the number of apoptotic cells in group III was reduced compared with that in group II. Compared with group II, treatment with batroxobin significantly increased the expression of VEGF from day 3 until 2 weeks post-SCI (P<0.05), while no significant difference was observed at day 28. These data suggest that batroxobin has multiple beneficial effects on SCI, indicating a potential clinical application. PMID:26136870

  20. Reduced expression of sushi domain containing 2 is associated with progression of non-small cell lung cancer

    PubMed Central

    CAI, CUIXIA; SHI, RONG; GAO, YUAN; ZENG, JUN; WEI, MIN; WANG, HANDUO; ZHENG, WENLING; MA, WENLI

    2015-01-01

    Sushi domain containing 2 (SUSD2) has been identified as a gene encoding an 822-amino acid protein, which contains a transmembrane domain and functional domains inherent to adhesion molecules. Previous studies have reported that increased expression of SUSD2 has a critical role in tumorigenesis in human breast cancer. However, to the best of our knowledge, SUSD2 expression status and its correlation with the clinicopathological features of non-small cell lung cancer (NSCLC) have not previously been investigated. In the present study, reverse transcription-quantitative polymerase chain reaction and western blotting were used to evaluate SUSD2 messenger RNA (mRNA) and protein expression in NSCLC and adjacent normal lung tissues. The clinicopathological significance of SUSD2 was investigated by immunohistochemical analysis of an NSCLC tissue microarray. Receiver operating characteristic analysis was used to determine the cut-off score for positive expression of SUSD2. Furthermore, the correlation between SUSD2 expression and the clinicopathological features of NSCLC was analyzed by χ2 test. The results revealed that SUSD2 mRNA (P<0.0001) and protein (P<0.0001) expression levels were significantly decreased in NSCLC tissues compared with those of adjacent normal tissues. When the SUSD2 positive expression percentage was determined to be >47.5% (area under ROC curve, 0.799; P<0.000), positive expression of SUSD2 was observed in 100% (32/32) of normal lung tissues and 55% (88/160) of NSCLC tissues by immunohistochemistry (χ2=21.160; P<0.000). Furthermore, it was demonstrated that the reduced SUSD2 protein levels in cancer tissues were positively correlated with poor histological grade (χ2=41.764; P<0.000), advanced clinical stage (χ2=10.790; P=0.013), higher pT (χ2=9.070; P=0.028) and positive regional lymph node metastasis (χ2=15.399; P=0.002). In conclusion, these data suggest that the reduced expression of SUSD2 is associated with the progression of NSCLC and

  1. Variable expression of epitopes on the surface of Mycoplasma gallisepticum demonstrated with monoclonal antibodies.

    PubMed

    Bencina, D; Kleven, S H; Elfaki, M G; Snoj, A; Dovc, P; Dorrer, D; Russ, I

    1994-03-01

    Twelve monoclonal antibodies (Mabs) against Mycoplasma gallisepticum (Mg) strains F, R, S6(208) and PET2 were used for analysis of epitopes of 22 Mg strains. Six Mabs recognized surface epitopes in the majority of strains, but did not react with variant strains like K 503 and K 703. Two Mabs reacted with epitopes on about 56 kilodalton (kDa) proteins and showing consistent expression on Mg colonies. Three Mabs recognized three different variable surface epitopes associated with about 67 kDa proteins and one Mab variable epitope on about 33 and 80 kDa proteins. Two-dimensional immunoblotting showed considerable differences in the charge of proteins bearing variable surface epitopes in different Mg strains. Subcloning of four low passage Mg strains using Mabs for screening populations that derived from a single colony with defined surface epitopes showed that some colonies may switch surface epitopes associated with 67 and 80 kDa proteins. This switching was reversible and generated subpopulations of Mg expressing different combinations of surface epitopes. Phenotypic switching of epitopes probably occurs also in vivo and may be the mechanism enabling Mg to evade the host immune response. PMID:18671069

  2. Reducing phosphorus flux from organic soils in surface flow treatment wetlands.

    PubMed

    Lindstrom, Susan M; White, John R

    2011-10-01

    Treatment wetlands have a finite period of effective nutrient removal after which treatment efficiency declines. This is due to the accumulation of organic matter which decreases the capacity and hydraulic retention time of the wetland. We investigated four potential solutions to improve the soluble reactive P (SRP) removal of a municipal wastewater treatment wetland soil including; dry down, surface additions of alum or calcium carbonate and physical removal of the accreted organic soil under both aerobic and anaerobic water column conditions. The flux of SRP from the soil to the water column under aerobic conditions was higher for the continuously flooded controls (1.1±0.4 mg P m(-2) d(-1)), dry down (1.5±0.9 mg P m(-2) d(-1)) and CaCO3 (0.8±0.7 mg P m(-2) d(-1)) treatments while the soil removal and alum treatments were significantly lower at 0.02±0.10 and -0.07±0.02 mg P m(-2) d(-1), respectively. These results demonstrate that the two most effective management strategies at sequestering SRP were organic soil removal and alum additions. There are difficulties and costs associated with removal and disposal of soils from a treatment wetland. Therefore our findings suggest that alum addition may be the most cost effective and efficient means of increasing the sequestering of P in aging treatment wetlands experiencing reduced P removal rates. However, more research is needed to determine the longer term effects of alum buildup in the organic soil on the wetland biota, in particular, on the macrophytes and invertebrates. Since alum effectiveness is time limited, a longer term solution to P flux may favor the organic soil removal. PMID:21802114

  3. A High Soy Diet Reduces Programmed Cell Death and Enhances Bcl-xL Expression In Experimental Stroke

    PubMed Central

    Lovekamp-Swan, Tara; Glendenning, Michele; Schreihofer, Derek A.

    2009-01-01

    Soy phytoestrogens have been proposed as an alternative to estrogen replacement therapy and have demonstrated potential neuroprotective effects in the brain. We have shown that a high soy diet significantly reduces infarct size following permanent middle cerebral artery occlusion (MCAO). Here, we tested the hypothesis that a high soy diet would attenuate programmed cell death after stroke. Adult female Sprague-Dawley rats were ovariectomized and fed either an isoflavone-reduced diet (IFP) or a high soy diet (SP) for 2 weeks before undergoing 90 minutes of transient MCAO (tMCAO) followed by 22.5 hr reperfusion. Infarct size, as assessed by TTC staining, was significantly reduced by a high soy diet (p< 0.05). Apoptosis in the ischemic cortex, measured by TUNEL staining, was significantly reduced by the high soy diet. The number of active caspase-3 positive cells and caspase-mediated α-spectrin cleavage was also significantly decreased in the ischemic cortex of SP rats. Furthermore, nuclear translocation of apoptosis-inducing factor (AIF) was significantly reduced in the ischemic cortex of SP rats. Soy significantly increased bcl-xL mRNA and protein expression in the ischemic cortex compared to IFP rats. Immunohistochemistry revealed increased neuronal expression of bcl-2 and bcl-xL in the ischemic cortex of both IFP and SP rats following tMCAO. These results suggest that a high soy diet decreases both caspase-dependent and caspase-independent programmed cell death following tMCAO. Further, a high soy diet enhances expression of the cell survival factor bcl-xL following tMCAO, contributing to the neuroprotective effects of soy in the ischemic cortex. PMID:17706879

  4. Does Expressive Writing Reduce Stress and Improve Health for Family Caregivers of Older Adults?

    ERIC Educational Resources Information Center

    Mackenzie, Corey S.; Wiprzycka, Ursula J.; Hasher, Lynn; Goldstein, David

    2007-01-01

    Purpose: We examined whether written emotional disclosure reduces stress and improves health outcomes for family caregivers of physically frail and cognitively impaired older adults, as it has been shown to do for certain student and clinical populations. Design and Methods: Primary caregivers of older adults attending a day program were randomly…

  5. Density enhanced phosphatase-1 down-regulates urokinase receptor surface expression in confluent endothelial cells

    PubMed Central

    Brunner, Patrick M.; Heier, Patricia C.; Mihaly-Bison, Judit; Priglinger, Ute; Binder, Bernd R.

    2011-01-01

    VEGF165, the major angiogenic growth factor, is known to activate various steps in proangiogenic endothelial cell behavior, such as endothelial cell migration and invasion, or endothelial cell survival. Thereby, the urokinase-type plasminogen activator (uPA) system has been shown to play an essential role not only by its proteolytic capacities, but also by induction of intracellular signal transduction. Therefore, expression of its cell surface receptor uPAR is thought to be an essential regulatory mechanism in angiogenesis. We found that uPAR expression on the surface of confluent endothelial cells was down-regulated compared with subconfluent proliferating endothelial cells. Regulation of uPAR expression was most probably affected by extracellular signal-regulated kinase 1/2 (ERK1/2) activation, a downstream signaling event of the VEGF/VEGF-receptor system. Consistently, the receptor-like protein tyrosine phosphatase DEP-1 (density enhanced phosphatase-1/CD148), which is abundantly expressed in confluent endothelial cells, inhibited the VEGF-dependent activation of ERK1/2, leading to down-regulation of uPAR expression. Overexpression of active ERK1 rescued the DEP-1 effect on uPAR. That DEP-1 plays a biologic role in angiogenic endothelial cell behavior was demonstrated in endothelial cell migration, proliferation, and capillary-like tube formation assays in vitro. PMID:21304107

  6. Gene expression profiling and mechanism study of neural stem cells response to surface chemistry

    PubMed Central

    Wang, Ying; Yao, Shenglian; Meng, Qingyuan; Yu, Xiaolong; Wang, Xiumei; Cui, Fuzhai

    2014-01-01

    To declare the mechanisms of neural stem cells (NSCs) in response to material surface chemistry, NSCs were exposed to the self-assemble monolayers of alkanethiolates on gold surfaces terminated with amine (NH2), hydroxyl (OH) and methyl (CH3) for analysis. The morphological responses of NSCs were recorded; the gene expression profilings were detected by genechips; the gene expressions data of NSCs responded to different chemical groups were declared through the gene ontology term and pathway analyses. It showed that cells behaved dissimilar on the three chemical groups, the adhesion, proliferation and migration were easier on the NH2 and OH groups; the gene expressions of NSCs were induced differently, either, involved in several functional processes and signaling pathways. CH3 group induced genes enriched much in chemistry reactions and death processes, whereas many genes of cellular nucleotide metabolism were down-regulated. NH2 group induced NSCs to express many genes of receptors on membrane, and participated in cellular signal transduction of cell adhesion and interactions, or associated with axon growth. OH group was similar to NH2 group to induce the membrane response, but it also down regulated metabolism of cells. Therefore, it declared the chemical groups affected NSCs through inner way and the NH2, OH and CH3 groups triggered the cellular gene expression in different signaling pathways. PMID:26816623

  7. CDK5 interacts with Slo and affects its surface expression and kinetics through direct phosphorylation

    PubMed Central

    Bai, Jun-Ping; Surguchev, Alexei; Joshi, Powrnima; Gross, Liza

    2012-01-01

    Large-conductance calcium-activated potassium (BK) channels are ubiquitous and play an important role in a number of diseases. In hair cells of the ear, they play a critical role in electrical tuning, a mechanism of frequency discrimination. These channels show variable kinetics and expression along the tonotopic axis. Although the molecular underpinnings to its function in hair cells are poorly understood, it is established that BK channels consist of a pore-forming α-subunit (Slo) and a number of accessory subunits. Here we identify CDK5, a member of the cyclin-dependent kinase family, as an interacting partner of Slo. We show CDK5 to be present in hair cells and expressed in high concentrations in the cuticular plate and in the circumferential zone. In human embryonic kidney cells, we show that CDK5 inhibits surface expression of Slo by direct phosphorylation of Slo. Similarly, we note that CDK5 affects Slo voltage activation and deactivation kinetics, by a direct phosphorylation of T847. Taken together with its increasing expression along the tonotopic axis, these data suggest that CDK5 likely plays a critical role in electrical tuning and surface expression of Slo in hair cells. PMID:22094329

  8. Zinc-ion implanted and deposited titanium surfaces reduce adhesion of Streptococccus mutans

    NASA Astrophysics Data System (ADS)

    Xu, Juan; Ding, Gang; Li, Jinlu; Yang, Shenhui; Fang, Bisong; Sun, Hongchen; Zhou, Yanmin

    2010-10-01

    While titanium (Ti) is a commonly used dental implant material with advantageous biocompatible and mechanical properties, native Ti surfaces do not have the ability to prevent bacterial colonization. The objective of this study was to evaluate the chemical composition and bacterial adhesive properties of zinc (Zn) ion implanted and deposited Ti surfaces (Zn-PIIID-Ti) as potential dental implant materials. Surfaces of pure Ti (cp-Ti) were modified with increasing concentrations of Zn using plasma immersion ion implantation and deposition (PIIID), and elemental surface compositions were characterized by X-ray photoelectron spectrometry (XPS). To evaluate bacterial responses, Streptococcus mutans were seeded onto the modifiedTi surfaces for 48 h and subsequently observed by scanning electron microscopy. Relative numbers of bacteria on each surface were assessed by collecting the adhered bacteria, reculturing and counting colony forming units after 48 h on bacterial grade plates. Ti, oxygen and carbon elements were detected on all surfaces by XPS. Increased Zn signals were detected on Zn-PIIID-Ti surfaces, correlating with an increase of Zn-deposition time. Substantial numbers of S. mutans adhered to cp-Ti samples, whereas bacterial adhesion on Zn-PIIID-Ti surfaces signficantly decreased as the Zn concentration increased ( p < 0.01). In conclusion, PIIID can successfully introduce Zn onto a Ti surface, forming a modified surface layer bearing Zn ions that consequently deter adhesion of S. mutans, a common bacterium in the oral environment.

  9. Phase Variation Mediates Reductions in Expression of Surface Proteins during Persistent Meningococcal Carriage

    PubMed Central

    Alamro, Mohamed; Bidmos, Fadil A.; Chan, Hannah; Oldfield, Neil J.; Newton, Emma; Bai, Xilian; Aidley, Jack; Care, Rory; Mattick, Claire; Turner, David P. J.; Neal, Keith R.; Ala'Aldeen, Dlawer A. A.; Feavers, Ian; Borrow, Ray

    2014-01-01

    Asymptomatic and persistent colonization of the upper respiratory tract by Neisseria meningitidis occurs despite elicitation of adaptive immune responses against surface antigens. A putative mechanism for facilitating host persistence of this bacterial commensal and pathogen is alterations in expression of surface antigens by simple sequence repeat (SSR)-mediated phase variation. We investigated how often phase variation occurs during persistent carriage by analyzing the SSRs of eight loci in multiple isolates from 21 carriers representative of 1 to 6 months carriage. Alterations in repeat number were detected by a GeneScan analysis and occurred at 0.06 mutations/gene/month of carriage. The expression states were determined by Western blotting and two genes, fetA and nadA, exhibited trends toward low expression states. A critical finding from our unique examination of combinatorial expression states, “phasotypes,” was for significant reductions in expression of multiple phase-variable surface proteins during persistent carriage of some strains. The immune responses in these carriers were examined by measuring variant-specific PorA IgG antibodies, capsular group Y IgG antibodies and serum bactericidal activity in concomitant serum samples. Persistent carriage was associated with high levels of specific IgG antibodies and serum bactericidal activity while recent strain acquisition correlated with a significant induction of antibodies. We conclude that phase-variable genes are driven into lower expression states during long-term persistent meningococcal carriage, in part due to continuous exposure to antibody-mediated selection, suggesting localized hypermutation has evolved to facilitate host persistence. PMID:24686058