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Sample records for polarized madin-darby canine

  1. Sorting of membrane and fluid at the apical pole of polarized Madin-Darby canine kidney cells.

    PubMed

    Leung, S M; Ruiz, W G; Apodaca, G

    2000-06-01

    When fluid-phase markers are internalized from opposite poles of polarized Madin-Darby canine kidney cells, they accumulate in distinct apical and basolateral early endosomes before meeting in late endosomes. Recent evidence suggests that significant mixing of apically and basolaterally internalized membrane proteins occurs in specialized apical endosomal compartments, including the common recycling endosome and the apical recycling endosome (ARE). The relationship between these latter compartments and the fluid-labeled apical early endosome is unknown at present. We report that when the apical recycling marker, membrane-bound immunoglobulin A (a ligand for the polymeric immunoglobulin receptor), and fluid-phase dextran are cointernalized from the apical poles of Madin-Darby canine kidney cells, they enter a shared apical early endosome (

  2. Sorting of Membrane and Fluid at the Apical Pole of Polarized Madin-Darby Canine Kidney Cells

    PubMed Central

    Leung, Som-Ming; Ruiz, Wily G.; Apodaca, Gerard

    2000-01-01

    When fluid-phase markers are internalized from opposite poles of polarized Madin-Darby canine kidney cells, they accumulate in distinct apical and basolateral early endosomes before meeting in late endosomes. Recent evidence suggests that significant mixing of apically and basolaterally internalized membrane proteins occurs in specialized apical endosomal compartments, including the common recycling endosome and the apical recycling endosome (ARE). The relationship between these latter compartments and the fluid-labeled apical early endosome is unknown at present. We report that when the apical recycling marker, membrane-bound immunoglobulin A (a ligand for the polymeric immunoglobulin receptor), and fluid-phase dextran are cointernalized from the apical poles of Madin-Darby canine kidney cells, they enter a shared apical early endosome (≤2.5 min at 37°C) and are then rapidly segregated from one another. The dextran remains in the large supranuclear EEA1-positive early endosomes while recycling polymeric immunoglobulin receptor–bound immunoglobulin A is delivered to a Rab11-positive subapical recycling compartment. This latter step requires an intact microtubule cytoskeleton. Receptor-bound transferrin, a marker of the basolateral recycling pathway, has limited access to the fluid-rich apical early endosome but is excluded from the subapical elements of the Rab11-positive recycling compartment. We propose that the term ARE be used to describe the subapical Rab11-positive compartment and that the ARE is distinct from both the transferrin-rich common recycling endosome and the fluid-rich apical early endosome. PMID:10848634

  3. Toxin sensitivity of the calcium-dependent rubidium efflux in Madin-Darby canine kidney cells.

    PubMed

    Tauc, M; Gastineau, M; Poujeol, P

    1993-01-29

    86Rb+ efflux was measured on polarized Madin-Darby canine kidney cells under A23187 or ATP stimulation. This efflux, inhibited by barium, Leiurus quinquestriatus hebraeus venom and charybdotoxin was attributed to the stimulation of Ca(++)-activated maxi K+ channels. Snake venom from Dendroaspis polylepis did not alter the stimulation as well as did apamine. ATP was effective on both the apical and basolateral membranes and the Ca(++)-activated maxi K+ channels were predominantly found on the basolateral membrane. This study presents the physiological evidence that dendrotoxin is ineffective on the epithelial Ca(++)-activated maxi K+ channel present in MDCK cells. PMID:7678959

  4. Microtubule-acting drugs lead to the nonpolarized delivery of the influenza hemagglutinin to the cell surface of polarized Madin-Darby canine kidney cells.

    PubMed

    Rindler, M J; Ivanov, I E; Sabatini, D D

    1987-02-01

    The synchronized directed transfer of the envelope glycoproteins of the influenza and vesicular stomatitis viruses from the Golgi apparatus to the apical and basolateral surfaces, respectively, of polarized Madin-Darby canine kidney (MDCK) cells can be achieved using temperature-sensitive mutant viruses and appropriate temperature shift protocols (Rindler, M. J., I. E. Ivanov, H. Plesken, and D. D. Sabatini, 1985, J. Cell Biol., 100:136-151). The microtubule-depolymerizing agents colchicine and nocodazole, as well as the microtubule assembly-promoting drug taxol, were found to interfere with the normal polarized delivery and exclusive segregation of hemagglutinin (HA) to the apical surface but not with the delivery and initial accumulation of G on the basolateral surface. Immunofluorescence analysis of permeabilized monolayers of influenza-infected MDCK cells treated with the microtubule-acting drugs demonstrated the presence of substantial amounts of HA protein on both the apical and basolateral surfaces. Moreover, in cells infected with the wild-type influenza virus, particles budded from both surfaces. Viral counts in electron micrographs showed that approximately 40% of the released viral particles accumulated in the intercellular spaces or were trapped between the cell and monolayer and the collagen support as compared to less than 1% on the basolateral surface of untreated infected cells. The effect of the microtubule inhibitors was not a result of a rapid redistribution of glycoprotein molecules initially delivered to the apical surface since a redistribution was not observed when the inhibitors were added to the cells after the HA was permitted to reach the apical surface at the permissive temperature and the synthesis of new HA was inhibited with cycloheximide. The altered segregation of the HA protein that occurs may result from the dispersal of the Golgi apparatus induced by the inhibitors or from the disruption of putative microtubules containing tracks

  5. Characterization of hormone-sensitive Madin-Darby canine kidney cells

    SciTech Connect

    Lin, M.C.; Beckner, S.K.; Darfler, F.J.

    1985-01-01

    The paper describes the optimal conditions for maintaining hormone responsiveness, measurement of intracellular AMP, and the characteristics of several types of hormone sensitivity in Madin-Darby canine kidney cells. Cyclic AMP is measured by radioimmunoassay with (/sup 175/I) as tracer. The responsiveness of the kidney cells to glucagon, vasopressin, isoproterenol, and prostaglandin in presented.

  6. EphrinA1-EphA2 Signal Induces Compaction and Polarization of Madin-Darby Canine Kidney Cells by Inactivating Ezrin through Negative Regulation of RhoA*

    PubMed Central

    Wakayama, Yuki; Miura, Koichi; Sabe, Hisataka; Mochizuki, Naoki

    2011-01-01

    The epithelial cells exhibit either a columnar or a flat shape dependent on extracellular stimuli or the cell-cell adhesion. Membrane-anchored ephrinA stimulates EphA receptor tyrosine kinases as a ligand in a cell-cell contact-dependent manner. The mechanism through which ephrinA1/EphA2 signal regulates the cell morphology remains elusive. We demonstrate here that ephrinA1/EphA2 signal induces compaction and enhanced polarization (columnar change) of Madin-Darby canine kidney epithelial cells by regulating Ezrin, a linker that connects plasma membrane and actin cytoskeleton. Activation of EphA2 resulted in RhoA inactivation through p190RhoGAP-A and subsequent dephosphorylation of Ezrin on Thr-567 phosphorylated by Rho kinase. Consistently, the cells expressing an active mutant of Ezrin in which Thr-567 was replaced with Asp did not change their shape in response to ephrinA1. Furthermore, depletion of Ezrin led to compaction and enhanced polarization without ephrinA1 stimulation, suggesting the role for active Ezrin in keeping the flat cell shape. Ezrin localized to apical domain irrespective of ephrinA1 stimulation, whereas phosphorylated Ezrin on the apical domain was reduced by ephrinA1 stimulation. Collectively, ephrinA1/EphA2 signal negatively regulates Ezrin and promotes the alteration of cell shape, from flat to columnar shape. PMID:21979959

  7. The Recycling Endosome of Madin-Darby Canine Kidney Cells Is a Mildly Acidic Compartment Rich in Raft Components

    PubMed Central

    Gagescu, Raluca; Demaurex, Nicolas; Parton, Robert G.; Hunziker, Walter; Huber, Lukas A.; Gruenberg, Jean

    2000-01-01

    We present a biochemical and morphological characterization of recycling endosomes containing the transferrin receptor in the epithelial Madin-Darby canine kidney cell line. We find that recycling endosomes are enriched in molecules known to regulate transferrin recycling but lack proteins involved in early endosome membrane dynamics, indicating that recycling endosomes are distinct from conventional early endosomes. We also find that recycling endosomes are less acidic than early endosomes because they lack a functional vacuolar ATPase. Furthermore, we show that recycling endosomes can be reached by apically internalized tracers, confirming that the apical endocytic pathway intersects the transferrin pathway. Strikingly, recycling endosomes are enriched in the raft lipids sphingomyelin and cholesterol as well as in the raft-associated proteins caveolin-1 and flotillin-1. These observations may suggest that a lipid-based sorting mechanism operates along the Madin-Darby canine kidney recycling pathway, contributing to the maintenance of cell polarity. Altogether, our data indicate that recycling endosomes and early endosomes differ functionally and biochemically and thus that different molecular mechanisms regulate protein sorting and membrane traffic at each step of the receptor recycling pathway. PMID:10930469

  8. Toxin pharmacology of the ATP-induced hyperpolarization in Madin-Darby canine kidney cells.

    PubMed

    Tauc, M; Gastineau, M; Poujeol, P

    1992-03-23

    The effects of Leiurus quinquestriatus hebraeus (LQH) venom, mamba venom, Buthus tamulus (BT) venom, purified apamin and synthetic charybdotoxin on the membrane hyperpolarization induced by extracellular ATP were examined in Madin-Darby canine kidney cells. For this we used a membrane potential probe (bisoxonol) to determine the potential variations. The relation between bisoxonal fluorescence and membrane potential was established by treating Madin-Darby canine kidney cells suspended in solutions containing various external sodium concentrations with gramicidin. Extracellular ATP induced a rapid hyperpolarization that was blocked by LQH venom and synthetic charybdotoxin. BT venom also blocked the response but at a much higher concentration than that of LQH. Mamba venom (Dendroaspis polylepis) and apamin did not modify the ATP-induced hyperpolarization. We concluded that the ATP induced hyperpolarization was due to the augmentation of the potassium conductance probably through Ca(2+)-activated K+ channels sensitive to charybdotoxin but not to mamba venom. The interaction previously described between charybdotoxin and dendrotoxin (the main toxin of mamba venom) was not observed in our case. PMID:1373656

  9. Protein 4.1N is required for translocation of inositol 1,4,5-trisphosphate receptor type 1 to the basolateral membrane domain in polarized Madin-Darby canine kidney cells.

    PubMed

    Zhang, Songbai; Mizutani, Akihiro; Hisatsune, Chihiro; Higo, Takayasu; Bannai, Hiroko; Nakayama, Tomohiro; Hattori, Mitsuharu; Mikoshiba, Katsuhiko

    2003-02-01

    Protein 4.1N was identified as a binding molecule for the C-terminal cytoplasmic tail of inositol 1,4,5-trisphosphate receptor type 1 (IP(3)R1) using a yeast two-hybrid system. 4.1N and IP(3)R1 associate in both subconfluent and confluent Madin-Darby canine kidney (MDCK) cells, a well studied tight polarized epithelial cell line. In subconfluent MDCK cells, 4.1N is distributed in the cytoplasm and the nucleus; IP(3)R1 is localized in the cytoplasm. In confluent MDCK cells, both 4.1N and IP(3)R1 are predominantly translocated to the basolateral membrane domain, whereas 4.1R, the prototypical homologue of 4.1N, is localized at the tight junctions (Mattagajasingh, S. N., Huang, S. C., Hartenstein, J. S., and Benz, E. J., Jr. (2000) J. Biol. Chem. 275, 30573-30585), and other endoplasmic reticulum marker proteins are still present in the cytoplasm. Moreover, the 4.1N-binding region of IP(3)R1 is necessary and sufficient for the localization of IP(3)R1 at the basolateral membrane domain. A fragment of the IP(3)R1-binding region of 4.1N blocks the localization of co-expressed IP(3)R1 at the basolateral membrane domain. These data indicate that 4.1N is required for IP(3)R1 translocation to the basolateral membrane domain in polarized MDCK cells. PMID:12444087

  10. Transepithelial transport of aliphatic carboxylic acids studied in Madin Darby canine kidney (MDCK) cell monolayers

    SciTech Connect

    Cho, M.J.; Adson, A.; Kezdy, F.J. )

    1990-04-01

    Transport of 14C-labeled acetic, propionic (PA), butyric, valeric, heptanoic (HA), and octanoic (OA) acids across the Madin Darby canine kidney (MDCK) epithelial cell monolayer grown on a porous polycarbonate membrane was studied in Hanks' balanced salt solution (HBSS) at 37{degrees}C in both apical-to-basolateral and basolateral-to-apical directions. At micromolar concentrations of solutes, metabolic decomposition was significant as evidenced by (14C)CO2 production during the OA transport. The apparent permeability (Pe) indicates that as lipophilicity increases, diffusion across the unstirred boundary layer becomes rate limiting. In support of this notion, transport of OA and HA was enhanced by agitation, showed an activation energy of 3.7 kcal/mol for OA, and resulted in identical Pe values for both transport directions. Analysis of Pe changes with varying alkyl chain length resulted in a delta G of -0.68 +/- 0.09 kcal/mol for -CH2-group transfer from an aqueous phase to the MDCK cells. When the intercellular tight junctions were opened by the divalent chelator EGTA in Ca2+/Mg2(+)-free HBSS, transport of the fluid-phase marker Lucifer yellow greatly increased because of paracellular leakage. PA transport also showed a significant increase, but OA transport was independent of EGTA. Although albumin also undergoes paracellular transport in the presence of EGTA and OA binds strongly to albumin, OA transport in EGTA solution was unchanged by albumin. These observations indicate that transmembrane transport is the major mechanism for lipophilic substances. The present study, together with earlier work on the transport of polar substances, shows that the MDCK cell monolayer is an excellent model of the transepithelial transport barrier.

  11. Three-dimensional imaging of cholesterol and sphingolipids within a Madin-Darby canine kidney cell

    DOE PAGESBeta

    Yeager, Ashley N.; Weber, Peter K.; Kraft, Mary L.

    2016-01-08

    Metabolic stable isotope incorporation and secondary ion mass spectrometry(SIMS) depth profiling performed on a Cameca NanoSIMS 50 were used to image the 18O-cholesterol and 15N-sphingolipid distributions within a portion of a Madin-Darby canine kidney (MDCK) cell. Three-dimensional representations of the component-specific isotope distributions show clearly defined regions of 18O-cholesterol and 15N-sphingolipid enrichment that seem to be separate subcellular compartments. Furthermore, the low levels of nitrogen-containing secondary ions detected at the 18O-enriched regions suggest that these 18O-cholesterol-rich structures may be lipiddroplets, which have a core consisting of cholesterol esters and triacylglycerides.

  12. Three-dimensional imaging of cholesterol and sphingolipids within a Madin-Darby canine kidney cell.

    PubMed

    Yeager, Ashley N; Weber, Peter K; Kraft, Mary L

    2016-06-01

    Metabolic stable isotope incorporation and secondary ion mass spectrometry (SIMS) depth profiling performed on a Cameca NanoSIMS 50 were used to image the (18)O-cholesterol and (15)N-sphingolipid distributions within a portion of a Madin-Darby canine kidney (MDCK) cell. Three-dimensional representations of the component-specific isotope distributions show clearly defined regions of (18)O-cholesterol and (15)N-sphingolipid enrichment that seem to be separate subcellular compartments. The low levels of nitrogen-containing secondary ions detected at the (18)O-enriched regions suggest that these (18)O-cholesterol-rich structures may be lipid droplets, which have a core consisting of cholesterol esters and triacylglycerides. PMID:26746168

  13. Iterative sorting of apical and basolateral cargo in Madin-Darby canine kidney cells.

    PubMed

    Treyer, Aleksandr; Pujato, Mario; Pechuan, Ximo; Müsch, Anne

    2016-07-15

    For several decades, the trans-Golgi network (TGN) was considered the most distal stop and hence the ultimate protein-sorting station for distinct apical and basolateral transport carriers that reach their respective surface domains in the direct trafficking pathway. However, recent reports of apical and basolateral cargoes traversing post-Golgi compartments accessible to endocytic ligands before their arrival at the cell surface and the post-TGN breakup of large pleomorphic membrane fragments that exit the Golgi region toward the surface raised the possibility that compartments distal to the TGN mediate or contribute to biosynthetic sorting. Here we describe the development of a novel assay that quantitatively distinguishes different cargo pairs by their degree of colocalization at the TGN and by the evolution of colocalization during their TGN-to-surface transport. Keys to the high resolution of our approach are 1) conversion of perinuclear organelle clustering into a two-dimensional microsomal spread and 2) identification of TGN and post-TGN cargo without the need for a TGN marker that universally cosegregates with all cargo. Using our assay, we provide the first evidence that apical NTRp75 and basolateral VSVG in Madin-Darby canine kidney cells still undergo progressive sorting after they exit the TGN toward the cell surface. PMID:27226480

  14. Neutrophil-mediated transport of liposomes across the Madin Darby canine kidney epithelial cell monolayer.

    PubMed

    Cho, M J; Scieszka, J F; Cramer, C T; Thompson, D P; Vidmar, T J

    1989-01-01

    Targeted drug delivery to peripheral blood neutrophils (PMNs) should be of therapeutic potential in various disease states. In addition, substances taken up by PMNs in the circulation may be delivered to an extravascular site via the naturally occurring cell infiltration. The present study employs an in vitro chemotaxis model to test whether particulate drug carriers such as liposomes can be transported across a cellular barrier by migrating PMNs. The system contained 10(7) human PMNs/ml, 0.3-micron liposomes at a total lipid concentration of 2.5 mM, and 10% autologous human serum in the apical side of a confluent Madin Darby canine kidney (MDCK) epithelial cell monolayer of 4.71 cm2. The MDCK cells were grown on a polycarbonate membrane with 3-micron pores without any extracellular matrix, and 10(-7) M f-Met-Leu-Phe was added to the basolateral side as a trigger of chemotaxis. The aqueous phase of the reverse-phase evaporation vesicles (REVs) contained lucifer yellow CH (LY) and [14C]sucrose. The lipid bilayer of the REVs was spiked with [3H]dipalmitoylphosphatidylcholine (DPPC). Transmission electron micrographs showed that, in response to the formyl peptide, PMNs adhered to the apical surface of MDCK cells, emigrated across the MDCK cell layer, passed through the 3-micron pores in the polycarbonate membrane, and finally, appeared in the bottom well. Epifluorescence micrographs showed that most, if not all, of the migrated PMNs contained punctate fluorescence derived from LY. Transport data over a 3.5-hr period indicated that those markers that appeared in the basal side were indeed transported by phagocytosis of REVs by PMNs and that intact serum was an essential component in the process.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2717523

  15. Characterization of a Madin-Darby canine kidney cell line stably expressing TRPV5.

    PubMed

    den Dekker, Els; Schoeber, Joost; Topala, Catalin N; van de Graaf, Stan F J; Hoenderop, Joost G J; Bindels, René J M

    2005-07-01

    To provide a cell model for studying specifically the regulation of Ca2+ entry by the epithelial calcium channel transient receptor potential-vanilloid-5 (TRPV5), green fluorescent protein (GFP)-tagged TRPV5 was expressed stably in Madin-Darby canine kidney type I (MDCK) cells. The localization of GFP-TRPV5 in this cell line showed an intracellular granular distribution. Ca2+ uptake in GFP-TRPV5-MDCK cells cultured on plastic supports was threefold higher than in non-transfected cells. Moreover, apical Ca2+ uptake in GFP-TRPV5-MDCK cells cultured on permeable supports was eightfold higher than basolateral Ca2+ uptake, indicating that GFP-TRPV5 is expressed predominantly in the apical membrane. Patch-clamp analysis showed the presence of typical electrophysiological features of GFP-TRPV5, such as inwardly rectifying currents, inhibition by divalent cations and Ca2+-dependent inactivation. Moreover, the TRPV5 inhibitor ruthenium red completely inhibited Ca2+ uptake in GFP-TRPV5-MDCK cells, whereas Ca2+ uptake in non-transfected cells was not inhibited. The characterized GFP-TRPV5-MDCK cell line was used to assess the regulation of TRPV5. The protein kinase C activator phorbol 12-myristate 13-acetate and the cAMP-elevating compounds forskolin/3-isobutyl-1-methylxanthine, 8-Br-cAMP and PGE2 stimulated TRPV5 activity in GFP-TRPV5-MDCK cells by 121+/-7, 79+/-5, 55+/-4 and 61+/-7%, respectively. These compounds did not affect Ca2+ uptake in non-transfected cells. In conclusion, the GFP-TRPV5-MDCK cell line provides a model to specifically study the regulation of TRPV5 activity. PMID:15924239

  16. Apical sorting of a voltage- and Ca2+-activated K+ channel alpha -subunit in Madin-Darby canine kidney cells is independent of N-glycosylation.

    PubMed

    Bravo-Zehnder, M; Orio, P; Norambuena, A; Wallner, M; Meera, P; Toro, L; Latorre, R; González, A

    2000-11-21

    The voltage- and Ca(2+)-activated K(+) (K(V,Ca)) channel is expressed in a variety of polarized epithelial cells seemingly displaying a tissue-dependent apical-to-basolateral regionalization, as revealed by electrophysiology. Using domain-specific biotinylation and immunofluorescence we show that the human channel K(V,Ca) alpha-subunit (human Slowpoke channel, hSlo) is predominantly found in the apical plasma membrane domain of permanently transfected Madin-Darby canine kidney cells. Both the wild-type and a mutant hSlo protein lacking its only potential N-glycosylation site were efficiently transported to the cell surface and concentrated in the apical domain even when they were overexpressed to levels 200- to 300-fold higher than the density of intrinsic Slo channels. Furthermore, tunicamycin treatment did not prevent apical segregation of hSlo, indicating that endogenous glycosylated proteins (e.g., K(V,Ca) beta-subunits) were not required. hSlo seems to display properties for lipid-raft targeting, as judged by its buoyant distribution in sucrose gradients after extraction with either detergent or sodium carbonate. The evidence indicates that the hSlo protein possesses intrinsic information for transport to the apical cell surface through a mechanism that may involve association with lipid rafts and that is independent of glycosylation of the channel itself or an associated protein. Thus, this particular polytopic model protein shows that glycosylation-independent apical pathways exist for endogenous membrane proteins in Madin-Darby canine kidney cells. PMID:11069304

  17. Apical sorting of a voltage- and Ca2+-activated K+ channel α-subunit in Madin-Darby canine kidney cells is independent of N-glycosylation

    PubMed Central

    Bravo-Zehnder, Marcela; Orio, Patricio; Norambuena, Andrés; Wallner, Martin; Meera, Pratap; Toro, Ligia; Latorre, Ramón; González, Alfonso

    2000-01-01

    The voltage- and Ca2+-activated K+ (KV,Ca) channel is expressed in a variety of polarized epithelial cells seemingly displaying a tissue-dependent apical-to-basolateral regionalization, as revealed by electrophysiology. Using domain-specific biotinylation and immunofluorescence we show that the human channel KV,Ca α-subunit (human Slowpoke channel, hSlo) is predominantly found in the apical plasma membrane domain of permanently transfected Madin-Darby canine kidney cells. Both the wild-type and a mutant hSlo protein lacking its only potential N-glycosylation site were efficiently transported to the cell surface and concentrated in the apical domain even when they were overexpressed to levels 200- to 300-fold higher than the density of intrinsic Slo channels. Furthermore, tunicamycin treatment did not prevent apical segregation of hSlo, indicating that endogenous glycosylated proteins (e.g., KV,Ca β-subunits) were not required. hSlo seems to display properties for lipid-raft targeting, as judged by its buoyant distribution in sucrose gradients after extraction with either detergent or sodium carbonate. The evidence indicates that the hSlo protein possesses intrinsic information for transport to the apical cell surface through a mechanism that may involve association with lipid rafts and that is independent of glycosylation of the channel itself or an associated protein. Thus, this particular polytopic model protein shows that glycosylation-independent apical pathways exist for endogenous membrane proteins in Madin-Darby canine kidney cells. PMID:11069304

  18. Synergistic antioxidant activity of resveratrol with genistein in high-glucose treated Madin-Darby canine kidney epithelial cells

    PubMed Central

    CHU, CHISHIH; LU, FUNG-JOU; YEH, RANG-HUI; LI, ZIH-LING; CHEN, CHING-HSEIN

    2016-01-01

    Resveratrol (Re), a stilbenoid, is associated with a potential benefit in controlling certain biomarkers in type II diabetes. Genistein (Ge), a phytoestrogen, may act as an antioxidant and thus may diminish damaging effects of free radicals in tissues. In the present study, a potential synergistic antioxidant effect of an Re/Ge combination on high-glucose (HG) incubation in Madin-Darby canine kidney (MDCK) epithelial cells was evaluated. Compared with the treatment of Re or Ge alone, the Re/Ge combination synergistically decreased intracellular reactive oxygen species (ROS) and hydroxyl radicals in MDCK cells. This synergistic antioxidant effect correlated with the inhibition of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression and an increase in γ-glutamylcysteine synthetase expression. In addition, mitochondrial complex I, NADPH oxidase, xanthine oxidase and lipoxygenase contributed towards ROS overproduction when the MDCK cells were incubated with HG. In conclusion, the Re/Ge combination synergistically enhanced the antioxidant effect in HG-incubated kidney cells, possibly through an enhanced antioxidant regulation mechanism. The Re/Ge combination may be a potential benefit against oxidative stress in diabetes mellitus. PMID:26998274

  19. Sphingomyelin regulates the transbilayer movement of diacylglycerol in the plasma membrane of Madin-Darby canine kidney cells.

    PubMed

    Ueda, Yoshibumi; Makino, Asami; Murase-Tamada, Kotono; Sakai, Shota; Inaba, Takehiko; Hullin-Matsuda, Françoise; Kobayashi, Toshihide

    2013-08-01

    Diacylglycerol (DAG) is a key component in lipid metabolism and signaling. Previous model membrane studies using DAG analogs suggest their rapid membrane transbilayer movement. However, little is known about the DAG distribution and dynamics in cell membranes. Using live-cell fluorescence microscopy, we monitored the transbilayer movement of DAG with the yellow fluorescent protein-tagged C1AB domain from protein kinase C-γ (EYFP-C1AB), which selectively binds DAG. When HeLa cells were treated with Bacillus cereus phospholipase C (Bc-PLC) to produce DAG on the outer leaflet of the plasma membrane, intracellularly expressed EYFP-C1AB probe accumulated at the plasma membrane, indicating the transbilayer movement of the outer leaflet DAG to the inner leaflet. This Bc-PLC-induced translocation of EYFP-C1AB probe to the plasma membrane was not observed in the sphingolipid-enriched plasma membrane of Madin-Darby canine kidney cells, but was recovered after cell treatment with sphingomyelinase or preincubation with an inhibitor of sphingolipid biosynthesis. The inhibitory effect of sphingomyelin (SM) on the transbilayer movement of DAG was reproduced in model membranes using a fluorescent short-chain DAG analog. These results demonstrate that the SM content on the outer leaflet regulates the transbilayer movement of DAG in the plasma membrane, thus providing new insights into the dynamics of DAG in cell pathophysiology. PMID:23682124

  20. Analysis of transcriptomic and proteomic profiles demonstrates improved Madin-Darby canine kidney cell function in a renal microfluidic biochip.

    PubMed

    Snouber, Leila Choucha; Letourneur, Franck; Chafey, Philippe; Broussard, Cedric; Monge, Matthieu; Legallais, Cécile; Leclerc, Eric

    2012-01-01

    We have evaluated the influence of the microfluidic environment on renal cell functionality. For that purpose, we performed a time lapse transcriptomic and proteomic analysis in which we compared gene and protein expressions of Madin-Darby canine kidney cells after 24 h and 96 h of culture in both microfluidic biochips and plates. The transcriptomic and proteomic integration revealed that the ion transporters involved in calcium, phosphate, and sodium homoeostasis and several genes involved in H(+) transporters and pH regulation were up-regulated in microfluidic biochips. Concerning drug metabolism, we found Phase I (CYP P450), Phase II enzymes (GST), various multidrug resistance genes (MRP), and Phase III transporters (SLC) were also up-regulated in the biochips. Furthermore, the study shows that those inductions were correlated with the induction of the Ahr and Nrf-2 dependent pathways, which results in a global cytoprotective response induced by the microenvironment. However, there was no apoptosis situation or cell death in the biochips. Microfluidic biochips may thus provide an important insight into exploring xenobiotic injury and transport modifications in this type of bioartificial microfluidic kidney. Finally, the investigation demonstrated that combining the transcriptomic and proteomic analyses obtained from a cell "on chip" culture would provide a pertinent new tool in the mechanistic interpretation of cellular mechanisms for predicting kidney cell toxicity and renal clearance in vitro. PMID:22095740

  1. Failure-to-thrive syndrome associated with tumor formation by Madin-Darby canine kidney cells in newborn nude mice.

    PubMed

    Brinster, Lauren R; Omeir, Romelda L; Foseh, Gideon S; Macauley, Juliete N; Snoy, Philip J; Beren, Joel J; Teferedegne, Belete; Peden, Keith; Lewis, Andrew M

    2013-08-01

    Tumors that formed in newborn nude mice that were inoculated with 10(7) Madin-Darby canine kidney (MDCK) cells were associated with a failure-to-thrive (FTT) syndrome consisting of growth retardation, lethargy, weakness, and dehydration. Scoliosis developed in 41% of affected pups. Pups were symptomatic by week 2; severely affected pups became moribund and required euthanasia within 3 to 4 wk. Mice with FTT were classified into categories of mild, moderate, and severe disease by comparing their weight with that of age-matched normal nude mice. The MDCK-induced tumors were adenocarcinomas that invaded adjacent muscle, connective tissue, and bone; 6 of the 26 pups examined had lung metastases. The induction of FTT did not correlate with cell-line aggressiveness as estimated by histopathology or the efficiency of tumor formation (tumor-forming dose 50% endpoint range = 10(2.8) to 10(7.5)); however, tumor invasion of the paravertebral muscles likely contributed to the scoliosis noted. In contrast to the effect of MDCK cells, tumor formation observed in newborn mice inoculated with highly tumorigenic, human-tumor-derived cell lines was not associated with FTT development. We suggest that tumor formation and FTT are characteristics of these MDCK cell inocula and that FTT represents a new syndrome that may be similar to the cachexia that develops in humans with cancer or other diseases. PMID:24209967

  2. Depletion of E-Cadherin Disrupts Establishment but Not Maintenance of Cell Junctions in Madin-Darby Canine Kidney Epithelial Cells

    PubMed Central

    Capaldo, Christopher T.

    2007-01-01

    E-cadherin forms calcium-dependent homophilic intercellular adhesions between epithelial cells. These contacts regulate multiple aspects of cell behavior, including the organization of intercellular tight junctions (TJs). To distinguish between the roles of E-cadherin in formation versus maintenance of junctions, Madin-Darby canine kidney (MDCK) cells were depleted of E-cadherin by RNA interference. Surprisingly, reducing E-cadherin expression had little effect on the protein levels or localization of adherens junction (AJ) or TJ markers. The cells underwent morphological changes, as the normally flat apical surface swelled into a dome. However, apical–basal polarity was not compromised, transmembrane resistance was normal, and zonula occludin protein 1 dynamics at the TJs were unchanged. Additionally, an E-cadherin/Cadherin-6 double knockdown also failed to disrupt established TJs, although β-catenin was lost from the cell cortex. Nevertheless, cells depleted of E-cadherin failed to properly reestablish cell polarity after junction disassembly. Recovery of cell–cell adhesion, transepithelial resistance, and the localization of TJ and AJ markers were all delayed. In contrast, depletion of α-catenin caused long-term disruption of junctions. These results indicate that E-cadherin and Cadherin-6 function as a scaffold for the construction of polarized structures, and they become largely dispensable in mature junctions, whereas α-catenin is essential for the maintenance of functional junctions. PMID:17093058

  3. ToF-SIMS and laser-SNMS analysis of Madin-Darby canine kidney II cells with silver nanoparticles using an argon cluster ion beam.

    PubMed

    Nees, Ricarda; Pelster, Andreas; Körsgen, Martin; Jungnickel, Harald; Luch, Andreas; Galla, Hans-Joachim; Arlinghaus, Heinrich F

    2016-06-01

    The use of nanoparticles is one of the fastest expanding fields in industrial as well as in medical applications, owing to their remarkable characteristics. Silver nanoparticles (AgNPs) are among the most-commercialized nanoparticles because of their antibacterial effects. Laser postionization secondary neutral mass spectrometry (laser-SNMS) and time-of-flight secondary ion mass spectrometry in combination with argon cluster ion sputtering was used for the first time to investigate the effects of AgNPs on Madin-Darby canine kidney (MDCK) II cells. Depth profiles and high-resolution three dimensional (3D) images of nanoparticles and organic compounds from cells were obtained using an Ar cluster ion beam for sputtering and Bi3 (+) primary ions for the analysis. The 3D distribution of AgNPs and other organic compounds in MDCK II cells could be readily detected with very high efficiency, sensitivity, and submicron lateral resolution. The argon cluster ion beam is well suited for the sputtering of biological samples. It enables a high sample removal rate along with low molecular degradation. The outer membrane, the cytoplasm, and the nuclei of the cells could be clearly visualized using the signals PO(+) and C3H8N(+) or CN(+) and C3H8N(+). The laser-SNMS images showed unambiguously that AgNPs are incorporated by MDCK II cells and often form silver aggregates with a diameter of a few micrometers, mainly close to the outside of the cell nuclei. PMID:26671480

  4. Effects of cranberry extract on prevention of urinary tract infection in dogs and on adhesion of Escherichia coli to Madin-Darby canine kidney cells.

    PubMed

    Chou, Hsin-I; Chen, Kuan-Sheng; Wang, Hsien-Chi; Lee, Wei-Ming

    2016-04-01

    OBJECTIVE To determine effects of cranberry extract on development of urinary tract infection (UTI) in dogs and on adherence of Escherichia coli to Madin-Darby canine kidney (MDCK) cells. ANIMALS 12 client-owned dogs (in vivo experiment) and 6 client-owned dogs (in vitro experiment). PROCEDURES 12 dogs with a history of recurrent UTI received an antimicrobial (n = 6) or cranberry extract (6) orally for 6 months. Dogs were monitored for a UTI. For the in vitro experiment, cranberry extract was orally administered to 6 dogs for 60 days. Voided urine samples were collected from each dog before and 30 and 60 days after onset of extract administration. Urine was evaluated by use of a bacteriostasis assay. An antiadhesion assay and microscopic examination were used to determine inhibition of bacterial adherence to MDCK cells. RESULTS None of the 12 dogs developed a UTI. The bacteriostasis assay revealed no zone of inhibition for any urine samples. Bacterial adhesion was significantly reduced after culture with urine samples obtained at 30 and 60 days, compared with results for urine samples obtained before extract administration. Microscopic examination revealed that bacterial adherence to MDCK cells was significantly reduced after culture with urine samples obtained at 30 and 60 days, compared with results after culture with urine samples obtained before extract administration. CONCLUSIONS AND CLINICAL RELEVANCE Oral administration of cranberry extract prevented development of a UTI and prevented E coli adherence to MDCK cells, which may indicate it has benefit for preventing UTIs in dogs. PMID:27027843

  5. Expression Profile of Drug and Nutrient Absorption Related Genes in Madin-Darby Canine Kidney (MDCK) Cells Grown under Differentiation Conditions

    PubMed Central

    Quan, Yong; Jin, Yisheng; Faria, Teresa N.; Tilford, Charles A.; He, Aiqing; Wall, Doris A.; Smith, Ronald L.; Vig, Balvinder S.

    2012-01-01

    The expression levels of genes involved in drug and nutrient absorption were evaluated in the Madin-Darby Canine Kidney (MDCK) in vitro drug absorption model. MDCK cells were grown on plastic surfaces (for 3 days) or on Transwell® membranes (for 3, 5, 7, and 9 days). The expression profile of genes including ABC transporters, SLC transporters, and cytochrome P450 (CYP) enzymes was determined using the Affymetrix® Canine GeneChip®. Expression of genes whose probe sets passed a stringent confirmation process was examined. Expression of a few transporter (MDR1, PEPT1 and PEPT2) genes in MDCK cells was confirmed by RT-PCR. The overall gene expression profile was strongly influenced by the type of support the cells were grown on. After 3 days of growth, expression of 28% of the genes was statistically different (1.5-fold cutoff, p < 0.05) between the cells grown on plastic and Transwell® membranes. When cells were differentiated on Transwell® membranes, large changes in gene expression profile were observed during the early stages, which then stabilized after 5–7 days. Only a small number of genes encoding drug absorption related SLC, ABC, and CYP were detected in MDCK cells, and most of them exhibited low hybridization signals. Results from this study provide valuable reference information on endogenous gene expression in MDCK cells that could assist in design of drug-transporter and/or drug-enzyme interaction studies, and help interpret the contributions of various transporters and metabolic enzymes in studies with MDCK cells. PMID:24300234

  6. Effects of oxalate exposure on Madin-Darby canine kidney cells in culture: renal prothrombin fragment-1 mRNA expression.

    PubMed

    Moryama, Manabu T; Domiki, Chizue; Miyazawa, Katsuhito; Tanaka, Tatsuro; Suzuki, Koji

    2005-12-01

    It has been suggested that renal tubular cell damage induced by oxalic acid, one of the components of urinary calculi, may be involved in a variety of ways in the development of urolithiasis. During our study on a calculus related protein, renal prothrombin fragment-1 (RPTF-1), we noted that this is an inflammation related substance that mediates an acute inflammatory reaction, one of the original roles of prothrombin. RPTF-1 is a part of prothrombin that is a coagulation factor known to be expressed in the renal tubule. We examined whether oxalic acid may cause cytotoxic effects on tubular epithelial cells and whether such chemical stimulation may promote the translation of RPTF-1 mRNA into RPTF-1 proteins. We used Madin-Darby canine kidney (MDCK) cells derived from the distal tubule of a dog kidney. In this study, the effects of oxalic acid in culture solution at different concentrations on cytotoxicity were assessed using a MTT assay. The location of active oxygen species was identified using dichlorofluorescein diacetate. After the prothrombin sequence of RPTF-1 was confirmed in MDCK cells, RPTF-1 mRNA expression was determined by RT-PCR. The gene sequence of the same promoter area was ligated, and a luciferase sequence was inserted downstream of the vector. The target sequence was transfected into MDCK cells and the relation between oxalic acid and prothrombin promoter was examined. In addition, the variable expression of RPTF-1 mRNA was quantitatively compared depending on oxalic acid concentrations using real-time PCR. When cytotoxicity was investigated, cells were not damaged but, by contrast, were stimulated and activated under oxalic acid below a certain concentration. The relation between cytotoxicity on the cultured MDCK cell membrane and active oxygen species was confirmed. Luminescence in MDCK cells containing the luciferase gene was detected by the addition of oxalic acid, which activated the prothrombin promoter. A part of the prothrombin gene

  7. Oncogenic H-Ras Reprograms Madin-Darby Canine Kidney (MDCK) Cell-derived Exosomal Proteins Following Epithelial-Mesenchymal Transition*

    PubMed Central

    Tauro, Bow J.; Mathias, Rommel A.; Greening, David W.; Gopal, Shashi K.; Ji, Hong; Kapp, Eugene A.; Coleman, Bradley M.; Hill, Andrew F.; Kusebauch, Ulrike; Hallows, Janice L.; Shteynberg, David; Moritz, Robert L.; Zhu, Hong-Jian; Simpson, Richard J.

    2013-01-01

    Epithelial-mesenchymal transition (EMT) is a highly conserved morphogenic process defined by the loss of epithelial characteristics and the acquisition of a mesenchymal phenotype. EMT is associated with increased aggressiveness, invasiveness, and metastatic potential in carcinoma cells. To assess the contribution of extracellular vesicles following EMT, we conducted a proteomic analysis of exosomes released from Madin-Darby canine kidney (MDCK) cells, and MDCK cells transformed with oncogenic H-Ras (21D1 cells). Exosomes are 40–100 nm membranous vesicles originating from the inward budding of late endosomes and multivesicular bodies and are released from cells on fusion of multivesicular bodies with the plasma membrane. Exosomes from MDCK cells (MDCK-Exos) and 21D1 cells (21D1-Exos) were purified from cell culture media using density gradient centrifugation (OptiPrep™), and protein content identified by GeLC-MS/MS proteomic profiling. Both MDCK- and 21D1-Exos populations were morphologically similar by cryo-electron microscopy and contained stereotypical exosome marker proteins such as TSG101, Alix, and CD63. In this study we show that the expression levels of typical EMT hallmark proteins seen in whole cells correlate with those observed in MDCK- and 21D1-Exos, i.e. reduction of characteristic inhibitor of angiogenesis, thrombospondin-1, and epithelial markers E-cadherin, and EpCAM, with a concomitant up-regulation of mesenchymal makers such as vimentin. Further, we reveal that 21D1-Exos are enriched with several proteases (e.g. MMP-1, -14, -19, ADAM-10, and ADAMTS1), and integrins (e.g. ITGB1, ITGA3, and ITGA6) that have been recently implicated in regulating the tumor microenvironment to promote metastatic progression. A salient finding of this study was the unique presence of key transcriptional regulators (e.g. the master transcriptional regulator YBX1) and core splicing complex components (e.g. SF3B1, SF3B3, and SFRS1) in mesenchymal 21D1-Exos. Taken

  8. Oncogenic H-ras reprograms Madin-Darby canine kidney (MDCK) cell-derived exosomal proteins following epithelial-mesenchymal transition.

    PubMed

    Tauro, Bow J; Mathias, Rommel A; Greening, David W; Gopal, Shashi K; Ji, Hong; Kapp, Eugene A; Coleman, Bradley M; Hill, Andrew F; Kusebauch, Ulrike; Hallows, Janice L; Shteynberg, David; Moritz, Robert L; Zhu, Hong-Jian; Simpson, Richard J

    2013-08-01

    Epithelial-mesenchymal transition (EMT) is a highly conserved morphogenic process defined by the loss of epithelial characteristics and the acquisition of a mesenchymal phenotype. EMT is associated with increased aggressiveness, invasiveness, and metastatic potential in carcinoma cells. To assess the contribution of extracellular vesicles following EMT, we conducted a proteomic analysis of exosomes released from Madin-Darby canine kidney (MDCK) cells, and MDCK cells transformed with oncogenic H-Ras (21D1 cells). Exosomes are 40-100 nm membranous vesicles originating from the inward budding of late endosomes and multivesicular bodies and are released from cells on fusion of multivesicular bodies with the plasma membrane. Exosomes from MDCK cells (MDCK-Exos) and 21D1 cells (21D1-Exos) were purified from cell culture media using density gradient centrifugation (OptiPrep™), and protein content identified by GeLC-MS/MS proteomic profiling. Both MDCK- and 21D1-Exos populations were morphologically similar by cryo-electron microscopy and contained stereotypical exosome marker proteins such as TSG101, Alix, and CD63. In this study we show that the expression levels of typical EMT hallmark proteins seen in whole cells correlate with those observed in MDCK- and 21D1-Exos, i.e. reduction of characteristic inhibitor of angiogenesis, thrombospondin-1, and epithelial markers E-cadherin, and EpCAM, with a concomitant up-regulation of mesenchymal makers such as vimentin. Further, we reveal that 21D1-Exos are enriched with several proteases (e.g. MMP-1, -14, -19, ADAM-10, and ADAMTS1), and integrins (e.g. ITGB1, ITGA3, and ITGA6) that have been recently implicated in regulating the tumor microenvironment to promote metastatic progression. A salient finding of this study was the unique presence of key transcriptional regulators (e.g. the master transcriptional regulator YBX1) and core splicing complex components (e.g. SF3B1, SF3B3, and SFRS1) in mesenchymal 21D1-Exos. Taken

  9. Apical expression of human full-length hCEACAM1-4L protein renders the Madin Darby Canine Kidney cells responsive to lipopolysaccharide leading to TLR4-dependent Erk1/2 and p38 MAPK signalling.

    PubMed

    Liévin-Le Moal, Vanessa; Beau, Isabelle; Rougeaux, Clémence; Kansau, Imad; Fabrega, Sylvie; Brice, Cédric; Korotkova, Natalia; Moseley, Steve L; Servin, Alain L

    2011-05-01

    CEACAM1 expressed by granulocytes and epithelial cells is recognized as a membrane-associated receptor by some Gram-negative pathogens. Here we report a previously unsuspected role of human CEACAM1-4L (hCEACAM1-4L) in polarized epithelial cells. We find that in contrast with non-transfected cells, Madin Darby Canine Kidney strain II (MDCK) engineered for the apical expression of the long cytoplasmic chain protein hCEACAM1-4L showed a serum-independent increase in the phosphorylation of the extracellular signal-regulated kinase 1/2 (Erk1/2) and p38 mitogen-activated protein kinases (MAPKs) after treatment with lipopolysaccharide (LPS) of wild-type, diffusely adhering Afa/Dr Escherichia coli (Afa/Dr DAEC) strain IH11128. Aggregates of FITC-LPS bind the apical domain of MDCK-hCEACAM1-4L cells colocalizing with the apically expressed hCEACAM1-4L protein and do not bind MDCK-pCEP cells, and surface plasmon resonance analysis shows that LPS binds to the extracellular domain of the CEACAM1-4L protein. We showed that cell polarization and lipid rafts positively control the LPS-IH11128-induced phosphorylation of Erk1/2 in MDCK-hCEACAM1-4L cells. Structure-function analysis using mutated hCEACAM1-4L protein shows that the cytoplasmic domain of the protein is needed for LPS-induced MAPK signalling, and that phosphorylation of Tyr-residues is not increased in association with MAPK signalling. The hCEACAM1-4L-dependent Erk1/2 phosphorylation develops in the presence of lipid A and does not develop in the presence of penta-acylated LPS. Finally, small interfering RNA (siRNA) silencing of canine TLR4 abolishes the hCEACAM1-4L-dependent, LPS-induced phosphorylation of Erk1/2. Collectively, our results support the notion that the apically expressed, full-length hCEACAM1-4L protein functions as a novel LPS-conveying molecule at the mucosal surface of polarized epithelial cells for subsequent MD-2/TLR4 receptor-dependent MAPK Erk1/2 and p38 signalling. PMID:21352462

  10. Transformation of Madin-Darby canine kidney (MDCK) epithelial cells by Epstein-Barr virus latent membrane protein 1 (LMP1) induces expression of Ets1 and invasive growth.

    PubMed

    Kim, K R; Yoshizaki, T; Miyamori, H; Hasegawa, K; Horikawa, T; Furukawa, M; Harada, S; Seiki, M; Sato, H

    2000-03-30

    The Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) has a significant role in initiating EBV-associated lymphoproliferative disease and EBV-related malignancies. In view of clinical features related to the type of EBV latency, LMP1 may influence invasiveness of EBV associated tumors categorized as types II and III as represented on nasopharyngeal carcinoma (NPC). To screen for genes associated with invasion of epithelial cells transformed by LMP1, Madin-Darby canine kidney (MDCK) epithelial cells were transformed by LMP1. Stable transfection of a LMP1 gene into MDCK cells induced morphological change from cobblestone to a long spindle-shape, reduced cell-cell adhesion and caused high cell motility. Parental MDCK cells, which form spherical cysts in three-dimensional collagen gel matrix, form branching tubules following exposure to hepatocyte growth factor (HGF). MDCK cells transformed by LMP1 showed invasive growth to form branching tubules into collagen gel without HGF-treatment. mRNA differential display and Northern hybridization identified plasminogen activator inhibitor-1 (PAI-1), urokinase type plasminogen activator (uPA) and ets1 as genes upregulated during transformation by LMP1. Expression of a dominant negative type of Etsl in LMP1-transformed cells downregulated uPA expression and cell motility. Deletion of LMP1 cytoplasmic carboxy-terminal activating region 1 (CTAR1) domain abolished transformation, but a deletion mutant lacking CTAR2 domain still retained transforming and uPA-inducing ability. Expression of Ets1 was immunolocalized in tumor cells of NPC tissue which frequently express LMP1. Taken together, it is suggested that LMP1 induces expression of Ets1 which may contribute to invasion of NPC by stimulating cell motility and uPA expression. PMID:10777210

  11. Solute Carrier Family of the Organic Anion-Transporting Polypeptides 1A2- Madin-Darby Canine Kidney II: A Promising In Vitro System to Understand the Role of Organic Anion-Transporting Polypeptide 1A2 in Blood-Brain Barrier Drug Penetration.

    PubMed

    Liu, Houfu; Yu, Na; Lu, Sijie; Ito, Sumito; Zhang, Xuan; Prasad, Bhagwat; He, Enuo; Lu, Xinyan; Li, Yang; Wang, Fei; Xu, Han; An, Gang; Unadkat, Jashvant D; Kusuhara, Hiroyuki; Sugiyama, Yuichi; Sahi, Jasminder

    2015-07-01

    Organic anion-transporting polypeptide (OATP) 1A2 has the potential to be a target for central nervous system drug delivery due to its luminal localization at the human blood-brain barrier and broad substrate specificity. We found OATP1A2 mRNA expression in the human brain to be comparable to breast cancer resistance protein and OATP2B1 and much higher than P-glycoprotein (P-gp), and confirmed greater expression in the brain relative to other tissues. The goal of this study was to establish a model system to explore OATP1A2-mediated transcellular transport of substrate drugs and the interplay with P-gp. In vitro (human embryonic kidney 293 cells stably expressing Oatp1a4, the closest murine isoform) and in vivo (naïve and Oatp1a4 knock-out mice) studies with OATP1A2 substrate triptan drugs demonstrated that these drugs were not Oatp1a4 substrates. This species difference demonstrates that the rodent is not a good model to investigate the active brain uptake of potential OATP1A2 substrates. Thus, we constructed a novel OATP1A2 expressing Madin-Darby canine kidney (MDCK) II wild type and an MDCKII-multidrug resistance protein 1 (MDR1) system using BacMam virus transduction. The spatial expression pattern of OATP1A2 after transduction in MDCKII-MDR1 cells was superimposed to P-gp, confirming apical membrane localization. OATP1A2-mediated uptake of zolmitriptan, rosuvastatin, and fexofenadine across monolayers increased with increasing OATP1A2 protein expression. OATP1A2 counteracted P-gp efflux for cosubstrates zolmitriptan and fexofenadine. A three-compartment model incorporating OATP1A2-mediated influx was used to quantitatively describe the time- and concentration-dependent apical-to-basolateral transcellular transport of rosuvastatin across OATP1A2 expressing the MDCKII monolayer. This novel, simple and versatile experimental system is useful for understanding the contribution of OATP1A2-mediated transcellular transport across barriers, such as the blood

  12. Zinc Supplementation Protects against Cadmium Accumulation and Cytotoxicity in Madin-Darby Bovine Kidney Cells

    PubMed Central

    Zhang, Ding; Liu, Jingying; Gao, Jianfeng; Shahzad, Muhammad; Han, Zhaoqing; Wang, Zhi; Li, Jiakui; Sjölinder, Hong

    2014-01-01

    Cadmium ions (Cd2+) have been reported to accumulate in bovine tissues, although Cd2+ cytotoxicity has not been investigated thoroughly in this species. Zinc ions (Zn2+) have been shown to antagonize the toxic effects of heavy metals such as Cd2+ in some systems. The present study investigated Cd2+ cytotoxicity in Madin-Darby bovine kidney (MDBK) epithelial cells, and explored whether this was modified by Zn2+. Exposure to Cd2+ led to a dose- and time-dependent increase in apoptotic cell death, with increased intracellular levels of reactive oxygen species and mitochondrial damage. Zn2+ supplementation alleviated Cd2+-induced cytotoxicity and this protective effect was more obvious when cells were exposed to a lower concentration of Cd2+ (10 μM), as compared to 50 μM Cd2+. This indicated that high levels of Cd2+ accumulation might induce irreversible damage in bovine kidney cells. Metallothioneins (MTs) are metal-binding proteins that play an essential role in heavy metal ion detoxification. We found that co-exposure to Zn2+ and Cd2+ synergistically enhanced RNA and protein expression of MT-1, MT-2, and the metal-regulatory transcription factor 1 in MDBK cells. Notably, addition of Zn2+ reduced the amounts of cytosolic Cd2+ detected following MDBK exposure to 10 μM Cd2+. These findings revealed a protective role of Zn2+ in counteracting Cd2+ uptake and toxicity in MDBK cells, indicating that this approach may provide a means to protect livestock from excessive Cd2+ accumulation. PMID:25105504

  13. Protein kinase C is involved in stimulation of arachidonic acid metabolism in Madin-Darby canine kidney (MDCK) cells

    SciTech Connect

    Parker, J.; Daniel, L.W.; Waite, M.

    1986-05-01

    The authors used 12-O-tetradecanoyl-phorbol-13-acetate (TPA) to directly stimulate protein kinase C (PKC) in order to examine the role of PKC in transduction of biological signals that increase metabolism of arachidonic acid. Release of radioactive arachidonic acid and prostaglandins from TPA-stimulated MDCK cells is inhibited by either of two PKC inhibitors: 1-(5-isoquinolinesulfonyl)piperazine and 1-octadecyl-2-methoxy-glycero-3-phosphocholine (ALP). ALP is unable to inhibit cyclooxygenase when added into an in vitro assay for this enzyme. Furthermore, TPA induces de novo synthesis of cyclooxygenase in MDCK cells but ALP fails to prevent this effect of TPA. Thus, cyclooxygenase activity appears to be independent of PKC and TPA can still induce de novo synthesis of cyclooxygenase even in the presence of the PKC inhibitor ALP. Also, ALP has no effect on the release of arachidonic acid which occurs upon addition of the calcium ionophore A23187 to MDCK cells suggesting that there are multiple mechanisms to mobilize arachidonic acid. Their data indicate that activation of PKC by TPA leads to increased release of arachidonic acid through regulation of phospholipase(s) by PKC.

  14. Microtubules and actin filaments are not critically involved in the biogenesis of epithelial cell surface polarity.

    PubMed

    Salas, P J; Misek, D E; Vega-Salas, D E; Gundersen, D; Cereijido, M; Rodriguez-Boulan, E

    1986-05-01

    We have studied the role of microtubules and actin filaments in the biogenesis of epithelial cell surface polarity, using influenza hemagglutinin and vesicular stomatitis G protein as model apical and basolateral proteins in infected Madin-Darby canine kidney cells. Addition of colchicine or nocodazole to confluent monolayers at concentrations sufficient to completely disassemble microtubules did not affect the asymmetric budding of influenza or vesicular stomatitis virus and only slightly reduced the typical asymmetric surface distribution of their envelope proteins, despite extensive cytoplasmic redistribution of the Golgi apparatus. Alteration of microtubular function by taxol or dissociation of actin filaments by cytochalasin D also failed to have a significant effect. Furthermore, neither colchicine nor cytochalasin D pretreatment blocked the ability of subconfluent Madin-Darby canine kidney cells to sustain polarized budding of influenza virus a few hours after attachment to the substrate. Our results indicate that domain-specific microtubule or actin filament "tracks" are not responsible for the vectorial delivery of apically or basolaterally directed transport vesicles. In conjunction with currently available evidence, they are compatible with a model in which receptors in the cytoplasmic aspect of apical or basolateral regions provide vectoriality to the transport of vesicles carrying plasma membrane proteins to their final surface localization. PMID:2871031

  15. 2,3,7,8-Tetrachlorodibenzo-p-dioxin increases Bovine Herpesvirus type-1 (BHV-1) replication in Madin-Darby Bovine Kidney (MDBK) cells in vitro.

    PubMed

    Fiorito, F; Pagnini, U; De Martino, L; Montagnaro, S; Ciarcia, R; Florio, S; Pacilio, M; Fucito, A; Rossi, A; Iovane, G; Giordano, A

    2008-01-01

    Dioxin-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a common environmental toxin of current interest. In the last years, higher levels of TCDD than those permitted in UE [European Commission. 2002. European Commission Recommendation 2002/201/CE. Official Gazette, L 67/69] were detected in milk samples from cow, water buffalo, goat, and sheep raised on some areas of Campania Region (South Italy). Dioxin often causes immunosuppression and might render the animal liable to viral infections. In addition, viral infections are able to alter the pattern of dioxin distribution in different organs of the exposed animals. Bovine Herpesvirus type-1 (BHV-1) is a widespread pathogen, which causes infectious rhinotracheitis and infectious pustular vulvovaginitis in cattle. Herein, we have studied the effects of TCDD and BHV-1 infection, in Madin-Darby Bovine Kidney (MDBK) cells, alone as well as in association, so as cellular proliferation, apoptosis, and virus replication. We have observed an increase in cell viability of confluent monolayers at low TCDD concentrations. TCDD treated cells demonstrated increased viability compared to controls as evaluated by MTT test. TCDD exposure increased cell proliferation but induced no changes on apoptosis. Cells exposed to TCDD along with BHV-1 showed a dose-dependent increase in cytopathy, represented by ample syncytia formation with the elimination of the cellular sheets and increased viral titer. These results suggest that TCDD increases viral replication in MDBK cells while BHV-1 further decreases viability of TCDD exposed cells. Since very low concentrations (0.01 pg/ml) are sufficient to augment BHV-1 titer, TCDD may contribute to reactivate BHV-1 from latency, leading to recurrent disease and increase virus transmission. PMID:17516555

  16. Localization of GFP-tagged concentrative nucleoside transporters in a renal polarized epithelial cell line.

    PubMed

    Mangravite, L M; Lipschutz, J H; Mostov, K E; Giacomini, K M

    2001-05-01

    Many nucleosides undergo active reabsorption within the kidney, probably via nucleoside transporters. To date, two concentrative nucleoside transporters have been cloned, the sodium-dependent purine-selective nucleoside transporter (SPNT) and concentrative nucleoside transporter 1 (CNT1). We report the stable expression of green fluorescence protein (GFP)-tagged SPNT and CNT1 in Madin-Darby canine kidney (MDCK) cells, a polarized renal epithelial line. We demonstrate that the GFP tag does not alter the substrate selectivity and only modestly affects the kinetic activity of the transporters. By using confocal microscopy and functional studies, both SPNT and CNT1 are localized primarily to the apical membrane of MDCK and LLC-PK(1) cells. Apical localization of these transporters suggests a role in renal nucleoside reabsorption and regulation of tubular function via the adenosine pathway. PMID:11292631

  17. Changes in ganglioside content affect the binding of Clostridium perfringens epsilon-toxin to detergent-resistant membranes of Madin-Darby canine kidney cells.

    PubMed

    Shimamoto, Seiko; Tamai, Eiji; Matsushita, Osamu; Minami, Junzaburo; Okabe, Akinobu; Miyata, Shigeru

    2005-01-01

    Epsilon-toxin (ET) of Clostridium perfringens, which causes fatal enterotoxemia in ungulates, was previously shown to bind to and form a heptameric pore within the detergent-resistant membranes (DRMs) of MDCK cells. Depletion of cholesterol has also been shown to decrease the cytotoxicity of ET and its heptamerization. In this study, we investigated the effects of changes in sphingolipids, other DRM components of MDCK cells, on the cells' susceptibility to ET. Treatment with fumonisin B1 and PDMP, inhibitors of sphingolipid and glycosphingolipid syntheses, respectively, increased the susceptibility, while D609, a sphingomyelin synthesis inhibitor, had the opposite effect. The exogenous addition of ganglioside G(M1) dramatically decreased the ET binding, heptamerization and cytotoxicity. These effects were shown not to be due to ET binding to G(M1) or to denaturation of ET. We also found that the ET cytotoxicity towards MDCK cells decreased with an increase in culture time. In accordance with the resistance observed for prolonged cultured cells, G(M3), a major ganglioside component, increased and sialidase treatment increased their susceptibility. These results suggest that membrane-anchored sialic acid of G(M3) within DRMs inhibits ET binding, leading to prevention of the heptamerization of ET and cell death. It is also suggested that sialidase produced by this organism aids the targeting of ET to MDCK cells. PMID:15781998

  18. The pro-inflammatory cytokine tumor necrosis factor α stimulates expression of the carnitine transporter OCTN2 (novel organic cation transporter 2) and carnitine uptake via nuclear factor-κB in Madin-Darby bovine kidney cells.

    PubMed

    Zhou, X; Ringseis, R; Wen, G; Eder, K

    2015-06-01

    Carnitine uptake into tissues is mediated mainly by the novel organic cation transporter 2 (OCTN2), whose expression is upregulated in the liver of early-lactating dairy cows. It has been shown recently that pro-inflammatory cytokines, including tumor necrosis factor α (TNFα), stimulate OCTN2 expression and carnitine uptake in intestinal cells and inflamed intestinal mucosa. Given that many early-lactating dairy cows show typical signs of hepatic and systemic inflammation, such as elevated concentrations of circulating TNFα and activation of the key regulator of inflammation, nuclear factor κB (NF-κB), in tissues, it is possible that upregulation of OCTN2 and increase of carnitine uptake by TNFα is mediated by NF-κB, a mechanism that might contribute to the upregulation of OCNT2 in the liver of early-lactating dairy cows. Thus, in the present study, we tested the hypothesis that TNFα stimulates OCTN2 gene expression and carnitine uptake via NF-κB in the bovine Madin-Darby bovine kidney (MDBK) cell line. Treatment with TNFα caused activation of NF-κB, increased the mRNA and protein concentration of OCTN2, and stimulated the uptake of carnitine in MDBK cells. In contrast, combined treatment of MDBK cells with TNFα and the NF-κB inhibitor BAY 11-7085 completely blocked the effect of TNFα on OCTN2 mRNA and protein concentration and uptake of carnitine. These findings suggest that the bovine OCTN2 gene and carnitine uptake are regulated by NF-κB. Future studies are required to show the in vivo relevance of this regulatory mechanism in cattle. PMID:25892691

  19. Exocyst requirement for endocytic traffic directed toward the apical and basolateral poles of polarized MDCK cells.

    PubMed

    Oztan, Asli; Silvis, Mark; Weisz, Ora A; Bradbury, Neil A; Hsu, Shu-Chan; Goldenring, James R; Yeaman, Charles; Apodaca, Gerard

    2007-10-01

    The octameric exocyst complex is associated with the junctional complex and recycling endosomes and is proposed to selectively tether cargo vesicles directed toward the basolateral surface of polarized Madin-Darby canine kidney (MDCK) cells. We observed that the exocyst subunits Sec6, Sec8, and Exo70 were localized to early endosomes, transferrin-positive common recycling endosomes, and Rab11a-positive apical recycling endosomes of polarized MDCK cells. Consistent with its localization to multiple populations of endosomes, addition of function-blocking Sec8 antibodies to streptolysin-O-permeabilized cells revealed exocyst requirements for several endocytic pathways including basolateral recycling, apical recycling, and basolateral-to-apical transcytosis. The latter was selectively dependent on interactions between the small GTPase Rab11a and Sec15A and was inhibited by expression of the C-terminus of Sec15A or down-regulation of Sec15A expression using shRNA. These results indicate that the exocyst complex may be a multipurpose regulator of endocytic traffic directed toward both poles of polarized epithelial cells and that transcytotic traffic is likely to require Rab11a-dependent recruitment and modulation of exocyst function, likely through interactions with Sec15A. PMID:17686995

  20. Polarized trafficking of the sorting receptor SorLA in neurons and MDCK cells.

    PubMed

    Klinger, Stine C; Højland, Anne; Jain, Shweta; Kjolby, Mads; Madsen, Peder; Svendsen, Anna Dorst; Olivecrona, Gunilla; Bonifacino, Juan S; Nielsen, Morten S

    2016-07-01

    The sorting receptor SorLA is highly expressed in neurons and is also found in other polarized cells. The receptor has been reported to participate in the trafficking of several ligands, some of which are linked to human diseases, including the amyloid precursor protein, TrkB, and Lipoprotein Lipase (LpL). Despite this, only the trafficking in nonpolarized cells has been described so far. Due to the many differences between polarized and nonpolarized cells, we examined the localization and trafficking of SorLA in epithelial Madin-Darby canine kidney (MDCK) cells and rat hippocampal neurons. We show that SorLA is mainly found in sorting endosomes and on the basolateral surface of MDCK cells and in the somatodendritic domain of neurons. This polarized distribution of SorLA respectively depends on an acidic cluster and an extended version of this cluster and involves the cellular adaptor complex AP-1. Furthermore, we show that SorLA can mediate transcytosis across a tight cell layer. PMID:27192064

  1. Pak1 Regulates the Orientation of Apical Polarization and Lumen Formation by Distinct Pathways

    PubMed Central

    Smits, Jos; ter Beest, Martin B.; Zegers, Mirjam M.

    2012-01-01

    The development of the basic architecture of branching tubules enclosing a central lumen that characterizes most epithelial organs crucially depends on the apico-basolateral polarization of epithelial cells. Signals from the extracellular matrix control the orientation of the apical surface, so that it faces the lumen interior, opposite to cell-matrix adhesion sites. This orientation of the apical surface is thought to be intrinsically linked to the formation of single lumens. We previously demonstrated in three-dimensional cyst cultures of Madin-Darby canine kidney (MDCK) cells that signaling by β1 integrins regulates the orientation of the apical surface, via a mechanism that depends on the activity of the small GTPase Rac1. Here, we investigated whether the Rac1 effector Pak1 is a downstream effector in this pathway. Expression of constitutive active Pak1 phenocopies the effect of β1 integrin inhibition in that it misorients the apical surface and induces a multilumen phenotype. The misorientation of apical surfaces depends on the interaction of active Pak1 with PIX proteins and is linked to defects in basement membrane assembly. In contrast, the multilumen phenotype was independent of PIX and the basement membrane. Therefore, Pak1 likely regulates apical polarization and lumen formation by two distinct pathways. PMID:22815903

  2. A Novel Human Cytomegalovirus Glycoprotein, gpUS9, Which Promotes Cell-to-Cell Spread in Polarized Epithelial Cells, Colocalizes with the Cytoskeletal Proteins E-Cadherin and F-Actin

    PubMed Central

    Maidji, Ekaterina; Tugizov, Sharof; Abenes, Gerardo; Jones, Thomas; Pereira, Lenore

    1998-01-01

    Processes by which human herpesviruses penetrate and are released from polarized epithelial cells, which have distinct apical and basolateral membrane domains differing in protein and lipid content, are poorly understood. We recently reported that human cytomegalovirus (CMV) mutants with deletions of the gene US9 formed wild-type plaques in cultures of human fibroblasts but were impaired in the capacity for cell-to-cell spread in polarized human retinal pigment epithelial cells. Unlike the glycoproteins that are required for infection, the protein encoded by CMV US9 plays an accessory role by promoting dissemination of virus across cell-cell junctions of polarized epithelial cells. To identify the product and investigate its specialized functions, we selected Madine-Darby canine kidney II (MDCK) epithelial cells that constitutively express CMV US9 or, as a control, US8. The gene products, designated gpUS9 and gpUS8, were glycosylated proteins of comparable molecular masses but differed considerably in intracellular distribution and solubility. Immunofluorescence laser scanning confocal microscopy indicated that, like gpUS8, gpUS9 was present in the endoplasmic reticulum and Golgi compartments of nonpolarized cells. In polarized epithelial cells, gpUS9 also accumulated along lateral membranes, colocalizing with cadherin and actin, and was insoluble in Triton X-100, a property shared with proteins that associate with the cytoskeleton. We hypothesize that gpUS9 may enhance the dissemination of CMV in infected epithelial tissues by associating with the cytoskeletal matrix. PMID:9621030

  3. p21-Activated kinase 2 (PAK2) inhibits TGF-β signaling in Madin-Darby canine kidney (MDCK) epithelial cells by interfering with the receptor-Smad interaction.

    PubMed

    Yan, Xiaohua; Zhang, Junyu; Sun, Qinyu; Tuazon, Polygena T; Wu, Xiaoping; Traugh, Jolinda A; Chen, Ye-Guang

    2012-04-20

    TGF-β (transforming growth factor β) plays a variety of cellular functions mainly through the Smad pathway. Phosphorylation of the carboxyl SXS motif in R-Smads (Smad2 and Smad3) by the type I receptor TβRI is a key step for their activation. It has been reported that the serine/threonine kinase PAK2 (p21-activated kinase 2) can mediate TGF-β signaling in mesenchymal cells. Here, we report that PAK2 restricts TGF-β-induced Smad2/3 activation and transcriptional responsiveness in MDCK epithelial cells. Mechanistically, PAK2 associates with Smad2 and Smad3 in a kinase activity-dependent manner and blocks their activation. PAK2 phosphorylates Smad2 at Ser-417, which is adjacent to the L3 loop that contributes to the TβRI-R-Smad association. Consistently, substitution of Ser-417 with glutamic acid attenuates the interaction of Smad2 with TβRI. Together, our results indicate that PAK2 negatively modulate TGF-β signaling by attenuating the receptor-Smad interaction and thus Smad activation. PMID:22393057

  4. Infection of polarized MDCK cells with herpes simplex virus 1: two asymmetrically distributed cell receptors interact with different viral proteins.

    PubMed Central

    Sears, A E; McGwire, B S; Roizman, B

    1991-01-01

    Herpes simplex virus 1 attaches to at least two cell surface receptors. In polarized epithelial (Madin-Darby canine kidney; MDCK) cells one receptor is located in the apical surface and attachment to the cells requires the presence of glycoprotein C in the virus. The second receptor is located in the basal surface and does not require the presence of glycoprotein C. Exposure of MDCK cells at either the apical or basal surface to wild-type virus yields plaques and viral products whereas infection by a glycoprotein C-negative mutant yields identical results only after exposure of MDCK cells to virus at the basal surface. Multiple receptors for viral entry into cells expand the host range of the virus. The observation that glycoprotein C-negative mutants are infectious in many nonpolarized cell lines suggests that cells in culture may express more than one receptor and explains why genes that specify the viral proteins that recognize redundant receptors, like glycoprotein C, are expendable. Images PMID:1647025

  5. Infection of Polarized MDCK Cells with Herpes Simplex Virus 1: Two Asymmetrically Distributed Cell Receptors Interact with Different Viral Proteins

    NASA Astrophysics Data System (ADS)

    Sears, Amy E.; McGwire, Bradford S.; Roizman, Bernard

    1991-06-01

    Herpes simplex virus 1 attaches to at least two cell surface receptors. In polarized epithelial (Madin-Darby canine kidney; MDCK) cells one receptor is located in the apical surface and attachment to the cells requires the presence of glycoprotein C in the virus. The second receptor is located in the basal surface and does not require the presence of glycoprotein C. Exposure of MDCK cells at either the apical or basal surface to wild-type virus yields plaques and viral products whereas infection by a glycoprotein C-negative mutant yields identical results only after exposure of MDCK cells to virus at the basal surface. Multiple receptors for viral entry into cells expand the host range of the virus. The observation that glycoprotein C-negative mutants are infectious in many nonpolarized cell lines suggests that cells in culture may express more than one receptor and explains why genes that specify the viral proteins that recognize redundant receptors, like glycoprotein C, are expendable.

  6. Na,K-ATPase β-Subunit Is Required for Epithelial Polarization, Suppression of Invasion, and Cell Motility

    PubMed Central

    Rajasekaran, Sigrid A.; Palmer, Lawrence G.; Quan, Karina; Harper, Jeffrey F.; Ball, William J.; Bander, Neil H.; Soler, Alejandro Peralta; Rajasekaran, Ayyappan K.

    2001-01-01

    The cell adhesion molecule E-cadherin has been implicated in maintaining the polarized phenotype of epithelial cells and suppression of invasiveness and motility of carcinoma cells. Na,K-ATPase, consisting of an α- and β-subunit, maintains the sodium gradient across the plasma membrane. A functional relationship between E-cadherin and Na,K-ATPase has not previously been described. We present evidence that the Na,K-ATPase plays a crucial role in E-cadherin–mediated development of epithelial polarity, and suppression of invasiveness and motility of carcinoma cells. Moloney sarcoma virus-transformed Madin-Darby canine kidney cells (MSV-MDCK) have highly reduced levels of E-cadherin and β1-subunit of Na,K-ATPase. Forced expression of E-cadherin in MSV-MDCK cells did not reestablish epithelial polarity or inhibit the invasiveness and motility of these cells. In contrast, expression of E-cadherin and Na,K-ATPase β1-subunit induced epithelial polarization, including the formation of tight junctions and desmosomes, abolished invasiveness, and reduced cell motility in MSV-MDCK cells. Our results suggest that E-cadherin–mediated cell-cell adhesion requires the Na,K-ATPase β-subunit's function to induce epithelial polarization and suppress invasiveness and motility of carcinoma cells. Involvement of the β1-subunit of Na,K-ATPase in the polarized phenotype of epithelial cells reveals a novel link between the structural organization and vectorial ion transport function of epithelial cells. PMID:11179415

  7. Human cytomegalovirus glycoprotein B contains autonomous determinants for vectorial targeting to apical membranes of polarized epithelial cells.

    PubMed

    Tugizov, S; Maidji, E; Xiao, J; Zheng, Z; Pereira, L

    1998-09-01

    We previously reported that human cytomegalovirus (CMV) glycoprotein B (gB) is vectorially transported to apical membranes of CMV-infected polarized human retinal pigment epithelial cells propagated on permeable filter supports and that virions egress predominantly from the apical membrane domain. In the present study, we investigated whether gB itself contains autonomous information for apical transport by expressing the molecule in stably transfected Madine-Darby canine kidney (MDCK) cells grown on permeable filter supports. Laser scanning confocal immunofluorescence microscopy and domain-selective biotinylation of surface membrane domains showed that CMV gB was transported to apical membranes independently of other envelope glycoproteins and that it colocalized with proteins in transport vesicles of the biosynthetic and endocytic pathways. Determinants for trafficking to apical membranes were located by evaluating the targeting of gB derivatives with deletions in the lumen, transmembrane (TM) anchor, and carboxyl terminus. Derivative gB(Delta717-747), with an internal deletion in the luminal juxtamembrane sequence that preserved the N- and O-glycosylation sites, retained vectorial transport to apical membranes. In contrast, derivatives that lacked the TM anchor and cytosolic domain (gBDelta646-906) or the TM anchor alone (gBDelta751-771) underwent considerable basolateral targeting. Likewise, derivatives lacking the entire cytosolic domain (gBDelta772-906) or the last 73 amino acids (gBDelta834-906) showed disrupted apical transport. Site-specific mutations that deleted or altered the cluster of acidic residues with a casein kinase II phosphorylation site at the extreme carboxyl terminus, which can serve as an internalization signal, caused partial missorting of gB to basolateral membranes. Our studies indicate that CMV gB contains autonomous information for apical targeting in luminal, TM anchor, and cytosolic domain sequences, forming distinct structural

  8. Human Cytomegalovirus Glycoprotein B Contains Autonomous Determinants for Vectorial Targeting to Apical Membranes of Polarized Epithelial Cells

    PubMed Central

    Tugizov, Sharof; Maidji, Ekaterina; Xiao, Jianqiao; Zheng, Zhenwei; Pereira, Lenore

    1998-01-01

    We previously reported that human cytomegalovirus (CMV) glycoprotein B (gB) is vectorially transported to apical membranes of CMV-infected polarized human retinal pigment epithelial cells propagated on permeable filter supports and that virions egress predominantly from the apical membrane domain. In the present study, we investigated whether gB itself contains autonomous information for apical transport by expressing the molecule in stably transfected Madine-Darby canine kidney (MDCK) cells grown on permeable filter supports. Laser scanning confocal immunofluorescence microscopy and domain-selective biotinylation of surface membrane domains showed that CMV gB was transported to apical membranes independently of other envelope glycoproteins and that it colocalized with proteins in transport vesicles of the biosynthetic and endocytic pathways. Determinants for trafficking to apical membranes were located by evaluating the targeting of gB derivatives with deletions in the lumen, transmembrane (TM) anchor, and carboxyl terminus. Derivative gB(Δ717-747), with an internal deletion in the luminal juxtamembrane sequence that preserved the N- and O-glycosylation sites, retained vectorial transport to apical membranes. In contrast, derivatives that lacked the TM anchor and cytosolic domain (gBΔ646-906) or the TM anchor alone (gBΔ751-771) underwent considerable basolateral targeting. Likewise, derivatives lacking the entire cytosolic domain (gBΔ772-906) or the last 73 amino acids (gBΔ834-906) showed disrupted apical transport. Site-specific mutations that deleted or altered the cluster of acidic residues with a casein kinase II phosphorylation site at the extreme carboxyl terminus, which can serve as an internalization signal, caused partial missorting of gB to basolateral membranes. Our studies indicate that CMV gB contains autonomous information for apical targeting in luminal, TM anchor, and cytosolic domain sequences, forming distinct structural elements that

  9. Glycoprotein E of Varicella-Zoster Virus Enhances Cell-Cell Contact in Polarized Epithelial Cells

    PubMed Central

    Mo, Chengjun; Schneeberger, Eveline E.; Arvin, Ann M.

    2000-01-01

    Varicella-zoster virus (VZV) infection involves the cell-cell spread of virions, but how viral proteins interact with the host cell membranes that comprise intercellular junctions is not known. Madin-Darby canine kidney (MDCK) cells were constructed to express the glycoproteins gE, gI, or gE/gI constitutively and were used to examine the effects of these VZV glycoproteins in polarized epithelial cells. At low cell density, VZV gE induced partial tight junction (TJ) formation under low-calcium conditions, whether expressed alone or with gI. Although most VZV gE was intracellular, gE was also shown to colocalize with the TJ protein ZO-1 with or without concomitant expression of gI. Freeze fracture electron microscopy revealed normal TJ strand morphology in gE-expressing MDCK cells. Functionally, the expression of gE was associated with a marked acceleration in the establishment of maximum transepithelial electrical resistance (TER) in MDCK-gE cells; MDCK-gI and MDCK-gE/gI cells exhibited a similar pattern of early TER compared to MDCK cells, although peak resistances were lower than those of gE alone. VZV gE expression altered F-actin organization and lipid distribution, but coexpression of gI modulated these effects. Two regions of the gE ectodomain, amino acids (aa) 278 to 355 and aa 467 to 498, although lacking Ca2+ binding motifs, exhibit similarities with corresponding regions of the cell adhesion molecules, E-cadherin and desmocollin. These observations suggest that VZV gE and gE/gI may contribute to viral pathogenesis by facilitating epithelial cell-cell contacts. PMID:11070038

  10. The Sec6/8 complex in mammalian cells: characterization of mammalian Sec3, subunit interactions, and expression of subunits in polarized cells.

    PubMed

    Matern, H T; Yeaman, C; Nelson, W J; Scheller, R H

    2001-08-14

    The yeast exocyst complex (also called Sec6/8 complex in higher eukaryotes) is a multiprotein complex essential for targeting exocytic vesicles to specific docking sites on the plasma membrane. It is composed of eight proteins (Sec3, -5, -6, -8, -10, and -15, and Exo70 and -84), with molecular weights ranging from 70 to 144 kDa. Mammalian orthologues for seven of these proteins have been described and here we report the cloning and initial characterization of the remaining subunit, Sec3. Human Sec3 (hSec3) shares 17% sequence identity with yeast Sec3p, interacts in the two-hybrid system with other subunits of the complex (Sec5 and Sec8), and is expressed in almost all tissues tested. In yeast, Sec3p has been proposed to be a spatial landmark for polarized secretion (1), and its localization depends on its interaction with Rho1p (2). We demonstrate here that hSec3 lacks the potential Rho1-binding site and GFP-fusions of hSec3 are cytosolic. Green fluorescent protein (GFP)-fusions of nearly every subunit of the mammalian Sec6/8 complex were expressed in Madin-Darby canine kidney (MDCK) cells, but they failed to assemble into a complex with endogenous proteins and localized in the cytosol. Of the subunits tested, only GFP-Exo70 localized to lateral membrane sites of cell-cell contact when expressed in MDCK cells. Cells overexpressing GFP-Exo70 fail to form a tight monolayer, suggesting the Exo70 targeting interaction is critical for normal development of polarized epithelial cells. PMID:11493706

  11. Epoxyeicosatrienoic acids affect electrolyte transport in renal tubular epithelial cells: dependence on cyclooxygenase and cell polarity.

    PubMed

    Nüsing, Rolf M; Schweer, Horst; Fleming, Ingrid; Zeldin, Darryl C; Wegmann, Markus

    2007-07-01

    We investigated the effects of epoxyeicosatrienoic acids (EETs) on ion transport in the polarized renal distal tubular cell line, Madin-Darby canine kidney (MDCK) C7. Of the four EET regioisomers (5,6-EET, 8,9-EET, 11,12-EET, and 14,15-EET) studied, only apical, but not basolateral, application of 5,6-EET increased short-circuit current (I(sc)) with kinetics similar to those of arachidonic acid. The ion transport was blocked by preincubation with the cyclooxygenase inhibitor indomethacin or with the chloride channel blocker NPPB. Furthermore, both a Cl(-)-free bath solution and the Ca(2+) antagonist verapamil blocked 5,6-EET-induced ion transport. Although the presence of the PGE(2) receptors EP2, EP3, and EP4 was demonstrated, apically added PGE(2) was ineffective and basolaterally added PGE(2) caused a different kinetics in ion transport compared with 5,6-EET. Moreover, PGE(2) synthesis in MDCK C7 cells was unaffected by 5,6-EET treatment. GC/MS/MS analysis of cell supernatants revealed the presence of the biologically inactive 5,6-dihydroxy-PGE(1) in 5,6-EET-treated cells, but not in control cells. Indomethacin suppressed the formation of 5,6-dihydroxy-PGE(1). 5,6-Epoxy-PGE(1), the precursor of 5,6-dihydroxy-PGE(1), caused a similar ion transport as 5,6-EET. Cytochrome P-450 enzymes homolog to human CYP2C8, CYP2C9, and CYP2J2 protein were detected immunologically in the MDCK C7 cells. Our findings suggest that 5,6-EET affects Cl(-) transport in renal distal tubular cells independent of PGE(2) but by a mechanism, dependent on its conversion to 5,6-epoxy-PGE(1) by cyclooxygenase. We suggest a role for this P450 epoxygenase product in the regulation of electrolyte transport, especially as a saluretic compound acting from the luminal side of tubular cells in the mammalian kidney. PMID:17494091

  12. Metabolic flux profiling of MDCK cells during growth and canine adenovirus vector production

    PubMed Central

    Carinhas, Nuno; Pais, Daniel A. M.; Koshkin, Alexey; Fernandes, Paulo; Coroadinha, Ana S.; Carrondo, Manuel J. T.; Alves, Paula M.; Teixeira, Ana P.

    2016-01-01

    Canine adenovirus vector type 2 (CAV2) represents an alternative to human adenovirus vectors for certain gene therapy applications, particularly neurodegenerative diseases. However, more efficient production processes, assisted by a greater understanding of the effect of infection on producer cells, are required. Combining [1,2-13C]glucose and [U-13C]glutamine, we apply for the first time 13C-Metabolic flux analysis (13C-MFA) to study E1-transformed Madin-Darby Canine Kidney (MDCK) cells metabolism during growth and CAV2 production. MDCK cells displayed a marked glycolytic and ammoniagenic metabolism, and 13C data revealed a large fraction of glutamine-derived labelling in TCA cycle intermediates, emphasizing the role of glutamine anaplerosis. 13C-MFA demonstrated the importance of pyruvate cycling in balancing glycolytic and TCA cycle activities, as well as occurrence of reductive alphaketoglutarate (AKG) carboxylation. By turn, CAV2 infection significantly upregulated fluxes through most central metabolism, including glycolysis, pentose-phosphate pathway, glutamine anaplerosis and, more prominently, reductive AKG carboxylation and cytosolic acetyl-coenzyme A formation, suggestive of increased lipogenesis. Based on these results, we suggest culture supplementation strategies to stimulate nucleic acid and lipid biosynthesis for improved canine adenoviral vector production. PMID:27004747

  13. A simplified system for generating recombinant E3-deleted canine adenovirus-2.

    PubMed

    Yu, Zuo; Jiang, Qian; Liu, Jiasen; Guo, Dongchun; Quan, Chuansong; Li, Botao; Qu, Liandong

    2015-01-01

    Canine adenovirus type 2 (CAV-2) has been used extensively as a vector for studying gene therapy and vaccine applications. We describe a simple strategy for generating a replication-competent recombinant CAV-2 using a backbone vector and a shuttle vector. The backbone plasmid containing the full-length CAV-2 genome was constructed by homologous recombination in Escherichia coli strain BJ5183. The shuttle plasmid, which has a deletion of 1478 bp in the nonessential E3 viral genome region, was generated by subcloning a fusion fragment containing the flanking sequences of the CAV-2 E3 region and expression cassette sequences from pcDNA3.1(+) into modified pUC18. To determine system effectiveness, a gene for enhanced green fluorescent protein (EGFP) was inserted into the shuttle plasmid and cloned into the backbone plasmid using two unique NruI and SalI sites. Transfection of Madin-Darby canine kidney (MDCK) cells with the recombinant adenovirus genome containing the EGFP expression cassette resulted in infectious viral particles. This strategy provides a solid foundation for developing candidate vaccines using CAV-2 as a delivery vector. PMID:25450764

  14. Hepatocyte growth factor/scatter factor effects on epithelia. Regulation of intercellular junctions in transformed and nontransformed cell lines, basolateral polarization of c-met receptor in transformed and natural intestinal epithelia, and induction of rapid wound repair in a transformed model epithelium.

    PubMed

    Nusrat, A; Parkos, C A; Bacarra, A E; Godowski, P J; Delp-Archer, C; Rosen, E M; Madara, J L

    1994-05-01

    Intestinal epithelial cells rest on a fibroblast sheath. Thus, factors produced by these fibroblasts may influence epithelial function in a paracrine fashion. We examined modulation of intestinal epithelial function by one such fibroblast product, scatter factor/hepatocyte growth factor (HGF/SF). This effect was studied in vitro by using model T84 intestinal epithelial cells. When applied to confluent T84 monolayers, HGF/SF attenuates transepithelial resistance to passive ion flow in a dose-dependent manner (maximum fall at 300 ng/ml, 28% control monolayer resistance, P < 0.001, ED50 of 1.2 nM), t1/2 of 20 h. This functional effect of HGF/SF and distribution of its receptor, c-met, are polarized to the basolateral membranes of T84 intestinal epithelial cells. HGF/SF effects on resistance are not attributable to altered transcellular resistance (opening of Cl- and/or basolateral K+ channels), cytotoxicity, or enhanced cell proliferation; they therefore represent specific regulation of paracellular tight junction resistance. Analysis with biochemically purified rodent HGF/SF and Madin-Darby canine kidney cells reveals that effects on paracellular tight junctions also occur in other nontransformed epithelia. Binding of HGF/SF to its receptor in T84 intestinal epithelial cells is accompanied by tyrosine phosphorylation of the receptor. Because loosening of intercellular junctions between cells could facilitate separation, spreading, and migration of epithelial cells during physiologic processes such as wound resealing, we determined the effects of HGF/SF on intestinal epithelial wound resealing using our previously published in vitro model (Nusrat, A., C. Delp, and J. L. Madara. 1992. J. Clin. Invest. 89:1501-1511). HGF/SF markedly enhanced wound closure (> 450% increase in rate, P < 0.001) by influencing the migratory and spreading response in not only cells adjoining the wound but also cells many positions removed from the wound. We thus speculate that HGF/SF may

  15. Kinetic analysis of human and canine P-glycoprotein-mediated drug transport in MDR1-MDCK cell model: approaches to reduce false-negative substrate classification.

    PubMed

    Li, Jibin; Wang, Ying; Hidalgo, Ismael J

    2013-09-01

    Madin-Darby canine kidney (MDCK) cells transfected with the multidrug resistance 1 (MDR1) gene, MDR1-MDCK, are widely used as an in vitro model to classify compounds as human P-glycoprotein (hPgp) substrates or nonsubstrates. Because MDCK cells express endogenous canine Pgp (cPgp), which is prone to downregulation after transfection with hPgp, this situation could lead to false-negative classification of hPgp substrates. The aim of this study was to investigate factors that influence hPgp substrate classification in MDR1-MDCK model and to seek ways to reduce false classification. Three-compartment models were used to derive flux equations describing the drug transport processes; factors influencing hPgp substrate classification were evaluated by simulations. Pgp functionality was assessed by determining the bidirectional permeability of a series of test compounds. Expressions of hPgp and cPgp were measured by quantitative polymerase chain reaction (qPCR). Kinetic model analysis revealed that the current net flux ratio calculation for hPgp substrate classification is influenced by endogenous cPgp expression as well as hPgp-cPgp expression ratio; the effect was more pronounced in low hPgp-cPgp region and diminished in high ratio region. On the basis of kinetic considerations, this study provides a rational experimental approach and appropriate mathematical corrections to minimize the potential occurrence of false-negative classification of new molecular entities. PMID:23558561

  16. Photoinduced cytotoxicity of a photochromic diarylethene via caspase cascade activation.

    PubMed

    Okuda, Jun-ya; Tanaka, Yukimi; Kodama, Ryuhei; Sumaru, Kimio; Morishita, Kana; Kanamori, Toshiyuki; Yamazoe, Seiji; Hyodo, Kengo; Yamazaki, Shohei; Miyatake, Tomohiro; Yokojima, Satoshi; Nakamura, Sinichiro; Uchida, Kingo

    2015-07-11

    The photo-generated closed-ring isomer of bis(5-methyl-2-phenylthiazoyl)perfluorocyclopentene shows cytotoxicity to Madin-Darby canine kidney (MDCK) cells through a caspase cascade and induces apoptosis of cells. PMID:26063471

  17. Production of canine adenovirus type 2 in serum-free suspension cultures of MDCK cells.

    PubMed

    Castro, R; Fernandes, P; Laske, T; Sousa, M F Q; Genzel, Y; Scharfenberg, K; Alves, P M; Coroadinha, A S

    2015-09-01

    The potential of adherent Madin Darby Canine Kidney (MDCK) cells for the production of influenza viruses and canine adenovirus type 2 (CAV-2) for vaccines or gene therapy approaches has been shown. Recently, a new MDCK cell line (MDCK.SUS2) that was able to grow in suspension in a fully defined system was established. In this work, we investigated whether the new MDCK.SUS2 suspension cell line is suitable for the amplification of CAV-2 under serum-free culture conditions. Cell growth performance and CAV-2 production were evaluated in three serum-free media: AEM, SMIF8, and EXCELL MDCK. CAV-2 production in shake flasks was maximal when AEM medium was used, resulting in an amplification ratio of infectious particles (IP) of 142 IP out/IP in and volumetric and cell-specific productivities of 2.1 × 10(8) IP/mL and 482 IP/cell, respectively. CAV-2 production was further improved when cells were cultivated in a 0.5-L stirred tank bioreactor. To monitor infection and virus production, cells were analyzed by flow cytometry. A correlation between the side scatter measurement and CAV-2 productivity was found, which represents a key feature to determine the best harvesting time during process development of gene therapy vectors that do not express reporter genes. This work demonstrates that MDCK.SUS2 is a suitable cell substrate for CAV-2 production, constituting a step forward in developing a production process transferable to industrial scales. This could allow for the production of high CAV-2 titers either for vaccination or for gene therapy purposes. PMID:25994255

  18. Diagnostic application of H3N8-specific equine influenza real-time reverse transcription polymerase chain reaction assays for the detection of Canine influenza virus in clinical specimens.

    PubMed

    Lu, Zhengchun; Dubovi, Edward J; Zylich, Nancy C; Crawford, P Cynda; Sells, Stephen; Go, Yun Young; Loynachan, Alan T; Timoney, Peter J; Chambers, Thomas M; Balasuriya, Udeni B R

    2010-11-01

    The objective of the current study was to determine the capability of 3 recently described one-step TaqMan real-time reverse transcription polymerase chain reaction (real-time RT-PCR) assays targeting the nucleoprotein (NP), matrix (M), and hemagglutinin (HA) genes of H3N8 Equine influenza virus (EIV NP, EIV M, and EIV HA3 assays, respectively) to detect Canine influenza virus (CIV). The assays were initially evaluated with nucleic acid extracted from tissue culture fluid (TCF) containing the A/canine/FL/43/04 strain of Influenza A virus associated with the 2004 canine influenza outbreak in Florida. The EIV NP, EIV M, and EIV HA3 assays could detect CIV nucleic acid at threshold cycle (Ct) values of 16.31, 23.71, and 15.28, respectively. Three assays using TCF or allantoic fluid (AF) samples containing CIV (n  =  13) and archived canine nasal swab samples (n  =  20) originally submitted for laboratory diagnosis of CIV were further evaluated. All TCF and AF samples, together with 10 nasal swab samples that previously tested positive for virus by attempted isolation in embryonated hens' eggs or Madin-Darby canine kidney cells, were positive in all 3 real-time RT-PCR assays. None of the 3 assays detected the H1N1 Swine influenza virus strain in current circulation. These findings demonstrate that previously described real-time RT-PCR assays targeting NP, M, and H3 HA gene segments of H3N8 EIV are also valuable for the diagnosis of CIV infection in dogs. The assays could expedite the detection and identification of CIV. PMID:21088179

  19. Enhanced replication of avian-origin H3N2 canine influenza virus in eggs, cell cultures and mice by a two-amino acid insertion in neuraminidase stalk.

    PubMed

    Lin, Yan; Xie, Xing; Zhao, Yanbing; Kalhoro, Dildar Hussain; Lu, Chengping; Liu, Yongjie

    2016-01-01

    Canine influenza virus (CIV) is a newly identified, highly contagious respiratory pathogen in dogs. Recent studies indicate that avian-origin H3N2 CIV are circulating in Chinese dogs. To investigate the effects of a two-amino acid (2-aa) insertion naturally occurring at the distal end of the neuraminidase (NA) stalk found in Chinese isolates since 2010 on virus replication and virulence, we rescued the CIV strain, A/canine/Jiangsu/06/2011(H3N2) and its NA mutant without the 2-aa insertion using reverse genetics. The NA stalk length affected virus growth in cell culture. Compared to the short stalk strain (without 2-aa insertion), the long stalk strain (with 2-aa insertion) exhibited higher peak titers and greater yields in Madin-Darby canine kidney (MDCK) cells, chicken embryo fibroblasts and canine bronchiolar epithelial cells, as well as much larger plaques in MDCK cell monolayers. Furthermore, mice inoculated with the long stalk strain showed more severe pathologic damage in lung and higher proportion of detectable viral RNA in tissues. The long stalk strain induced local IFN-γ production with faster kinetics and higher levels in mice. However, in chickens, the two viral strains showed no significant difference with nearly the same proportion of detectable viral RNA loads in tissues. These observations suggest that the 2-aa insertion in the NA stalk acquired by avian-origin H3N2 CIV helps to enhance viral replication and is likely a result of adaptive evolution in canine hosts. PMID:27160077

  20. Characteristics of taurine transport in cultured renal epithelial cell lines: asymmetric polarity of proximal and distal cell lines.

    PubMed

    Jones, D P; Miller, L A; Budreau, A; Chesney, R W

    1992-01-01

    Taurine transport was determined in two continuous, renal epithelial cell lines: LLC-PK1 derived from the proximal tubule of the pig, and the Madin-Darby canine kidney cell (MDCK) from the distal tubule of the dog. In LLC-PK1, taurine transport is maximal at the apical surface, whereas in MDCK cells, transport is greatest at the basolateral surface. Transport is highly dependent on both sodium and chloride in the external medium, and is specific for beta-amino acids. The apical and basolateral surfaces of both cell lines show an adaptive response to extracellular taurine concentration, but only the basolateral surface of the MDCK cell responds to hyperosomolality by increased taurine accumulation. Thus, differential control of the beta-amino acid transport system by substrate and external tonicity exists. The role of the beta-amino acid transport system may differ according to the origin of the cell: in the proximal renal tubular cell, net transepithelial reabsorption of filtered taurine increases the body pool. By contrast, taurine accumulation by distal tubular cells may form a mechanism of cell volume regulation in response to osmotic stress. PMID:1509959

  1. Transepithelial pressure pulses induce nucleotide release in polarized MDCK cells.

    PubMed

    Praetorius, H A; Frøkiaer, J; Leipziger, J

    2005-01-01

    The release of nucleotides is involved in mechanosensation in various epithelial cells. Intriguingly, kidney epithelial cells are absolutely dependent on the primary cilium to sense changes in apical laminar flow. During fluid passage, the renal epithelial cells are subjected to various mechanical stimuli in addition to changes in the laminar flow rate. In the distal part of the collecting duct, the epithelial cells are exposed to pressure changes and possibly distension during papillary contractions. The aim of the present study was to determine whether nucleotide release contributes to mechanosensation in kidney epithelial cells, thereby establishing whether pressure changes are sufficient to produce nucleotide-mediated responses. Madin-Darby canine kidney (MDCK) cells grown on permeable supports were mounted in a closed double perfusion chamber on an inverted microscope. The intracellular Ca(2+) concentration ([Ca(2+)](i)) was monitored with the Ca(2+)-sensitive fluorescence probe fluo 4. Transepithelial pressure pulses of 30-80 mm Hg produced a transient increase in [Ca(2+)](i) of MDCK cells. This response is independent of the primary cilium, since it is readily observed in immature cells that do not yet express primary cilia. The amplitudes of the pressure-induced Ca(2+) transients varied with the applied chamber pressure in a quantity-dependent manner. The ATPase apyrase and the P2Y antagonist suramin significantly reduced the pressure-induced Ca(2+) transients. Applying apyrase or suramin to both sides of the preparation simultaneously nearly abolished the pressure-induced Ca(2+) response. In conclusion, these observations suggest that rapid pressure changes induce both apical and basolateral nucleotide release that contribute to mechanosensation in kidney epithelial cells. PMID:15367389

  2. Galectin-7 modulates the length of the primary cilia and wound repair in polarized kidney epithelial cells.

    PubMed

    Rondanino, Christine; Poland, Paul A; Kinlough, Carol L; Li, Hui; Rbaibi, Youssef; Myerburg, Michael M; Al-bataineh, Mohammad M; Kashlan, Ossama B; Pastor-Soler, Nuria M; Hallows, Kenneth R; Weisz, Ora A; Apodaca, Gerard; Hughey, Rebecca P

    2011-09-01

    Galectins (Gal) are β-galactoside-binding proteins that function in epithelial development and homeostasis. An overlapping role for Gal-3 and Gal-7 in wound repair was reported in stratified epithelia. Although Gal-7 was thought absent in simple epithelia, it was reported in a proteomic analysis of cilia isolated from cultured human airway, and we recently identified Gal-7 transcripts in Madin-Darby canine kidney (MDCK) cells (Poland PA, Rondanino C, Kinlough CL, Heimburg-Molinaro J, Arthur CM, Stowell SR, Smith DF, Hughey RP. J Biol Chem 286: 6780-6790, 2011). We now report that Gal-7 is localized exclusively on the primary cilium of MDCK, LLC-PK(1) (pig kidney), and mpkCCD(c14) (mouse kidney) cells as well as on cilia in the rat renal proximal tubule. Gal-7 is also present on most cilia of multiciliated cells in human airway epithelia primary cultures. Interestingly, exogenous glutathione S-transferase (GST)-Gal-7 bound the MDCK apical plasma membrane as well as the cilium, while the lectin Ulex europeaus agglutinin, with glycan preferences similar to Gal-7, bound the basolateral plasma membrane as well as the cilium. In pull-down assays, β1-integrin isolated from either the basolateral or apical/cilia membranes of MDCK cells was similarly bound by GST-Gal-7. Selective localization of Gal-7 to cilia despite the presence of binding sites on all cell surfaces suggests that intracellular Gal-7 is specifically delivered to cilia rather than simply binding to surface glycoconjugates after generalized secretion. Moreover, depletion of Gal-7 using tetracycline-induced short-hairpin RNA in mpkCCD(c14) cells significantly reduced cilia length and slowed wound healing in a scratch assay. We conclude that Gal-7 is selectively targeted to cilia and plays a key role in surface stabilization of glycoconjugates responsible for integrating cilia function with epithelial repair. PMID:21677144

  3. A critical synopsis: Continuous growth of proximal tubular kidney epithelial cells in hormone-supplemented serum-free medium

    NASA Technical Reports Server (NTRS)

    Chuman, L. M.; FINE; COHEN; Saier, M. H.

    1985-01-01

    The kidney forms urine and reabsorbs electrolytes and water. Kidney cell lines and hormone supplemented serum free medium were used for growth. The hormones were insulin, transferrin, vasopressin, cholesterol, prostaglandins, hydrocortisone, and triidothyronine. Epithelial cell lines are polar and form hemicysts. The Madin-Darby canine kidney(MDCK) cell line used is distal tubulelike. LLC-PK sub 1 cells are derived from pig kidneys and have the properties of different kidney segments. The LLC-PK sub 1 cells with proximal tubule properties were maintained in hormone-supplemented serum free medium. Seven factors (the aforementioned homrones and selenium) were needed for growth. Hormone-defined medium supported LLC-PK sub 1 cell growth, allowed transport (as seen by hemicyst formation), and influenced cell morphology. Vasopressin (used for growth and morphology) could be partially replaced by isobutylmethylxanthine or dibutyryl cAMP. The defined medium was used to isolate rabbit proximal tubule kidney epithelial cells free of fibroblasts.

  4. Basic science track. Entry and release of canine coronavirus from polarized epithelial cells.

    PubMed

    Pratelli, Annamaria

    2011-01-01

    Virus entry into and release from epithelial cells are polarized as a result of the distribution of the viral receptors. In order to establish the polarity of entry and release of CCoV from epithelial cells, the interactions of the virus with A72 and CrFK cells grown on permeable supports was evaluated, and the amount of infective virus in the apical and in the basolateral media was determined and compared. Infection of A72 cells after different times post seeding demonstrated that CCoV grow after infection from both apical and basolateral sides. In CrFK cells, CCoV was observed in both compartments only in the later phase of the infection. To establish the reciprocal binding of CCoV on plasma membrane, A72 cells on a permeable support were preincubated with a mAb specific for CCoV. Infection from the apical side was blocked by mAb applied to that side; in contrast, such treatment on the basolateral side had no effect on the infectious process. Similarly, the low levels of CCoV observed after basolateral exposure to virus was abolished following mAb treatment of that side. The identification of CCoV into the basolateral medium could play an important role in the viral pathogenesis. PMID:21344143

  5. Dynamin Binding Protein (Tuba) Deficiency Inhibits Ciliogenesis and Nephrogenesis in Vitro and in Vivo.

    PubMed

    Baek, Jeong-In; Kwon, Sang-Ho; Zuo, Xiaofeng; Choi, Soo Young; Kim, Seok-Hyung; Lipschutz, Joshua H

    2016-04-15

    Dysfunction of renal primary cilia leads to polycystic kidney disease. We previously showed that the exocyst, a protein trafficking complex, is essential for ciliogenesis and regulated by multiple Rho and Rab family GTPases, such as Cdc42. Cdc42 deficiency resulted in a disruption of renal ciliogenesis and a polycystic kidney disease phenotype in zebrafish and mice. Here we investigate the role of Dynamin binding protein (also known as Tuba), a Cdc42-specific guanine nucleotide exchange factor, in ciliogenesis and nephrogenesis using Tuba knockdown Madin-Darby canine kidney cells and tuba knockdown in zebrafish. Tuba depletion resulted in an absence of cilia, with impaired apical polarization and inhibition of hepatocyte growth factor-induced tubulogenesis in Tuba knockdown Madin-Darby canine kidney cell cysts cultured in a collagen gel. In zebrafish, tuba was expressed in multiple ciliated organs, and, accordingly, tuba start and splice site morphants showed various ciliary mutant phenotypes in these organs. Co-injection of tuba and cdc42 morpholinos at low doses, which alone had no effect, resulted in genetic synergy and led to abnormal kidney development with highly disorganized pronephric duct cilia. Morpholinos targeting two other guanine nucleotide exchange factors not known to be in the Cdc42/ciliogenesis pathway and a scrambled control morpholino showed no phenotypic effect. Given the molecular nature of Cdc42 and Tuba, our data strongly suggest that tuba and cdc42 act in the same ciliogenesis pathway. Our study demonstrates that Tuba deficiency causes an abnormal renal ciliary and morphogenetic phenotype. Tuba most likely plays a critical role in ciliogenesis and nephrogenesis by regulating Cdc42 activity. PMID:26895965

  6. The ectopic expression of Snail in MDBK cells does not induce epithelial-mesenchymal transition

    PubMed Central

    IZAWA, GENYA; KOBAYASHI, WAKAKO; HARAGUCHI, MISAKO; SUDO, AKIHARU; OZAWA, MASAYUKI

    2015-01-01

    Epithelial-mesenchymal transition (EMT), a key process in the tumor metastatic cascade, is characterized by the loss of cell-cell junctions and cell polarity, as well as by the acquisition of migratory and invasive properties. However, the precise molecular events that initiate this complex EMT process are poorly understood. Snail expression induces EMT in Madin-Darby canine kidney (MDCK) cells and the human epidermoid carcinoma cell line, A431. Snail is a zinc finger transcription factor and triggers EMT by suppressing E-cadherin expression. In the present study, to broaden our knowledge of Snail-induced EMT, we generated stable Snail transfectants using Madin-Darby bovine kidney (MDBK) cells. Contrary to the MDCK or A431 cells examined in our previous studies, the MDBK cells transfected with the Snail construct maintained an epithelial morphology and showed no sign of reduced cell-cell adhesiveness compared to the control cells. Consistent with these observations, the down-regulation of epithelial marker proteins, e.g. E-cadherin and desmoglein, and the upregulation of mesenchymal marker proteins, e.g., N-cadherin and fibronectin, were not detected. Furthermore, the E-cadherin promoter was not methylated. Therefore, in the MDBK cells, the ectopic expression of Snail failed to induce EMT. As previously demonstrated, in MDCK cells, Snail expression is accompanied by the increased expression of other EMT-inducing transcription factors, e.g., Slug and zinc finger E-box-binding homeobox 1 (ZEB1). However, the MDBK cells transfected with the Snail construct did not exhibit an increased expression of these factors. Thus, it is possible that the failure to upregulate other EMT-related transcription factors may explain the lack of Snail-mediated induction of EMT in MDBK cells. PMID:25998899

  7. Canine Distemper

    MedlinePlus

    Although this brochure provides basic information about canine distemper, your veterinarian is always your best source of health information. Consult your veterinarian for more information about canine distemper and its prevention. ...

  8. Three-dimensional analysis of post-Golgi carrier exocytosis in epithelial cells.

    PubMed

    Kreitzer, Geri; Schmoranzer, Jan; Low, Seng Hui; Li, Xin; Gan, Yunbo; Weimbs, Thomas; Simon, Sanford M; Rodriguez-Boulan, Enrique

    2003-02-01

    Targeted delivery of proteins to distinct plasma membrane domains is critical to the development and maintenance of polarity in epithelial cells. We used confocal and time-lapse total internal reflection fluorescence microscopy (TIR-FM) to study changes in localization and exocytic sites of post-Golgi transport intermediates (PGTIs) carrying GFP-tagged apical or basolateral membrane proteins during epithelial polarization. In non-polarized Madin Darby Canine Kidney (MDCK) cells, apical and basolateral PGTIs were present throughout the cytoplasm and were observed to fuse with the basal domain of the plasma membrane. During polarization, apical and basolateral PGTIs were restricted to different regions of the cytoplasm and their fusion with the basal membrane was completely abrogated. Quantitative analysis suggested that basolateral, but not apical, PGTIs fused with the lateral membrane in polarized cells, correlating with the restricted localization of Syntaxins 4 and 3 to lateral and apical membrane domains, respectively. Microtubule disruption induced Syntaxin 3 depolarization and fusion of apical PGTIs with the basal membrane, but affected neither the lateral localization of Syntaxin 4 or Sec6, nor promoted fusion of basolateral PGTIs with the basal membrane. PMID:12545172

  9. 4.1N binding regions of inositol 1,4,5-trisphosphate receptor type 1.

    PubMed

    Fukatsu, Kazumi; Bannai, Hiroko; Inoue, Takafumi; Mikoshiba, Katsuhiko

    2006-04-01

    Zhang et al. and Maximov et al. [S. Zhang, A. Mizutani, C. Hisatsune, T. Higo, H. Bannai, T. Nakayama, M. Hattori, and K. Mikoshiba, Protein 4.1N is required for translocation of inositol 1,4,5-trisphosphate receptor type 1 to the basolateral membrane domain in polarized Madin-Darby canine kidney cells, J. Biol. Chem. 278 (2003) 4048-4056; A. Maximov, T. S. Tang, and I. Bezprozvanny, Association of the type 1 inositol (1,4,5)-trisphosphate receptor with 4.1N protein in neurons, Mol. Cell. Neurosci. 22 (2003) 271-283.] reported that 4.1N is a binding partner of inositol 1,4,5-trisphosphate receptor type 1 (IP(3)R1), however the binding site of IP(3)R1 differed: the former determined the C-terminal 14 amino acids of the cytoplasmic tail (CTT14aa) as the binding site, while the latter assigned another segment, cytoplasmic tail middle 1 (CTM1). To solve this discrepancy, we performed immunoprecipitation and found that both the segments had binding activity to 4.1N. Both segments also interfered the 4.1N-regulated IP(3)R1 diffusion in neuronal dendrites. However, IP(3)R1 lacking the CTT14aa (IP(3)R1-DeltaCTT14aa) does not bind to 4.1N [S. Zhang, A. Mizutani, C. Hisatsune, T. Higo, H. Bannai, T. Nakayama, M. Hattori, and K. Mikoshiba, Protein 4.1N is required for translocation of inositol 1,4,5-trisphosphate receptor type 1 to the basolateral membrane domain in polarized Madin-Darby canine kidney cells, J. Biol. Chem. 278 (2003) 4048-4056.] and its diffusion constant is larger than that of IP(3)R1 full-length in neuronal dendrites [K. Fukatsu, H. Bannai, S. Zhang, H. Nakamura, T. Inoue, and K. Mikoshiba, Lateral diffusion of inositol 1,4,5-trisphosphate receptor type 1 is regulated by actin filaments and 4.1N in neuronal dendrites, J. Biol. Chem. 279 (2004) 48976-48982.]. We conclude that both the CTT14aa and CTM1 sequences can bind to 4.1N in peptide fragment forms. However, we propose that the responsible binding site for 4.1N binding in full-length tetramer form of IP

  10. Ouabain modulates ciliogenesis in epithelial cells

    PubMed Central

    Larre, Isabel; Castillo, Aida; Flores-Maldonado, Catalina; Contreras, Ruben G.; Galvan, Ivan; Muñoz-Estrada, Jesus; Cereijido, Marcelino

    2011-01-01

    The exchange of substances between higher organisms and the environment occurs across transporting epithelia whose basic features are tight junctions (TJs) that seal the intercellular space, and polarity, which enables cells to transport substances vectorially. In a previous study, we demonstrated that 10 nM ouabain modulates TJs, and we now show that it controls polarity as well. We gauge polarity through the development of a cilium at the apical domain of Madin-Darby canine kidney cells (MDCK, epithelial dog kidney). Ouabain accelerates ciliogenesis in an ERK1/2-dependent manner. Claudin-2, a molecule responsible for the Na+ and H2O permeability of the TJs, is also present at the cilium, as it colocalizes and coprecipitates with acetylated α-tubulin. Ouabain modulates claudin-2 localization at the cilium through ERK1/2. Comparing wild-type and ouabain-resistant MDCK cells, we show that ouabain acts through Na+,K+-ATPase. Taken together, our previous and present results support the possibility that ouabain constitutes a hormone that modulates the transporting epithelial phenotype, thereby playing a crucial role in metazoan life. PMID:22143774

  11. Canine Parvovirus

    MedlinePlus

    Finally, do not let your puppy or adult dog to come into contact with the fecal waste of other dogs while walking or playing outdoors. Prompt and proper ... advisable as a way to limit spread of canine parvovirus infection as well as other diseases that ...

  12. Two distinct oncornaviruses harbor an intracytoplasmic tyrosine-based basolateral targeting signal in their viral envelope glycoprotein.

    PubMed Central

    Lodge, R; Delamarre, L; Lalonde, J P; Alvarado, J; Sanders, D A; Dokhélar, M C; Cohen, E A; Lemay, G

    1997-01-01

    It has been clearly established that the budding of the human immunodeficiency virus (HIV-1), a lentivirus, occurs specifically through the basolateral membrane in polarized epithelial cells. More recently, the signal was assigned to a tyrosine-based motif located in the intracytoplasmic domain of the envelope glycoprotein, as previously observed on various other viral and cellular basolateral proteins. In the present study, expression of human T-cell leukemia virus type 1 (HTLV-1) or Moloney murine leukemia virus envelope glycoproteins was used for trans-complementation of an envelope-negative HIV-1. This demonstrated the potential of oncornaviral retrovirus envelope glycoproteins to confer polarized basolateral budding in epithelial Madin-Darby canine kidney cells (MDCK cells). Site-directed mutagenesis confirmed the importance of a common motif encompassing at least one crucial membrane-proximal intracytoplasmic tyrosine residue. The conservation of a similar basolateral maturation signal in different retroviruses further supports its importance in the biology of this group of viruses. PMID:9188652

  13. VIP17/MAL expression modulates epithelial cyst formation and ciliogenesis

    PubMed Central

    Takiar, Vinita; Mistry, Kavita; Carmosino, Monica; Schaeren-Wiemers, Nicole

    2012-01-01

    The polarized organization of epithelial cells is required for vectorial solute transport and may be altered in renal cystic diseases. Vesicle integral protein of 17 kDa (VIP17/MAL) is involved in apical vesicle transport. VIP17/MAL overexpression in vivo results in renal cystogenesis of unknown etiology. Renal cystogenesis can occur as a consequence of defects of the primary cilium. To explore the role of VIP17/MAL in renal cystogenesis and ciliogenesis, we examined the polarization and ciliary morphology of wild-type and VIP17/MAL overexpressing Madin-Darby canine kidney renal epithelial cells grown in two-dimensional (2D) and three-dimensional (3D) cyst culture. VIP17/MAL is apically localized when expressed in cells maintained in 2D and 3D culture. VIP17/MAL overexpressing cells produce more multilumen cysts compared with controls. While the distributions of basolateral markers are not affected, VIP17/MAL expression results in aberrant sorting of the apical marker gp135 to the primary cilium. VIP17/MAL overexpression is also associated with shortened or absent cilia. Immunofluorescence analysis performed on kidney sections from VIP17/MAL transgenic mice also demonstrates fewer and shortened cilia within dilated lumens (P < 0.01). These studies demonstrate that VIP17/MAL overexpression results in abnormal cilium and cyst development, in vitro and in vivo, suggesting that VIP17/MAL overexpressing mice may develop cysts secondary to a ciliary defect. PMID:22895261

  14. Canine leishmaniosis.

    PubMed

    Sapierzyński, R

    2008-01-01

    Canine visceral leishmaniosis (CVL) is an infectious disease of zoonotic potential, caused by protozoan parasite of the genus Leishmania. Common clinical manifestations of canine visceral leishmaniosis include decrease of appetite, progressive weight loss, exercise intolerance, peripheral lymph node and spleen enlargement, chronic renal and liver disease, muscle, atrophy, polyarthritis and others. Because the Polish literature in the field contains no information on leishmaniosis in animals the recognised case of this disease is presented. Homeless mongrel, intact female dog, 3 years of age was brought to a veterinary clinic because of apathy, and generalised dermatologic lesions to perform routine examination. Because therapeutic effect of primarily recognised scabies was unsatisfactory, the skin samples from ear margins, trunk and lesion of the area of the left gluteal region for histopatologic examination were taken. Due to suspicion of leishmaniosis, fine-needle aspiration biopsy of lymph nodes, skin lesions, ocular discharge and imprint samples from skin lesion were performed, and tissue collected were examined under optical microscopy for identification of Leishmania amastigotes. To confirm cytologic diagnosis, blood samples for serological tests (enzyme-linked immunoabsorbent assay-ELISA; indirect immunofluorescence assay test-IFAT) were taken. Based on physical examination, histopatology, cytopathology and serology, canine visceral leishmaniosis was finally diagnosed. PMID:18683546

  15. Soybean extracts increase cell surface ZIP4 abundance and cellular zinc levels: a potential novel strategy to enhance zinc absorption by ZIP4 targeting.

    PubMed

    Hashimoto, Ayako; Ohkura, Katsuma; Takahashi, Masakazu; Kizu, Kumiko; Narita, Hiroshi; Enomoto, Shuichi; Miyamae, Yusaku; Masuda, Seiji; Nagao, Masaya; Irie, Kazuhiro; Ohigashi, Hajime; Andrews, Glen K; Kambe, Taiho

    2015-12-01

    Dietary zinc deficiency puts human health at risk, so we explored strategies for enhancing zinc absorption. In the small intestine, the zinc transporter ZIP4 functions as an essential component of zinc absorption. Overexpression of ZIP4 protein increases zinc uptake and thereby cellular zinc levels, suggesting that food components with the ability to increase ZIP4 could potentially enhance zinc absorption via the intestine. In the present study, we used mouse Hepa cells, which regulate mouse Zip4 (mZip4) in a manner indistinguishable from that in intestinal enterocytes, to screen for suitable food components that can increase the abundance of ZIP4. Using this ZIP4-targeting strategy, two such soybean extracts were identified that were specifically able to decrease mZip4 endocytosis in response to zinc. These soybean extracts also effectively increased the abundance of apically localized mZip4 in transfected polarized Caco2 and Madin-Darby canine kidney cells and, moreover, two apically localized mZip4 acrodermatitis enteropathica mutants. Soybean components were purified from one extract and soyasaponin Bb was identified as an active component that increased both mZip4 protein abundance and zinc levels in Hepa cells. Finally, we confirmed that soyasaponin Bb is capable of enhancing cell surface endogenous human ZIP4 in human cells. Our results suggest that ZIP4 targeting may represent a new strategy to improve zinc absorption in humans. PMID:26385990

  16. Epithelial cell invasion by bovine septicemic Escherichia coli.

    PubMed Central

    Korth, M J; Lara, J C; Moseley, S L

    1994-01-01

    Little is known regarding the pathogenesis of Escherichia coli-induced septicemic colibacillosis of calves. To understand the mechanism by which these strains penetrate the intestinal epithelium and gain access to the bloodstream, we examined the potential of bovine septicemic E. coli to invade cultured epithelial cells. By using a gentamicin survival assay, we demonstrated bacterial invasion of Madin-Darby canine kidney (MDCK) cells. Transcytosis of polarized MDCK cell monolayers was also observed, but only when bacteria were added to the basolateral surface. Electron microscopy confirmed the presence of intracellular organisms which appeared to be within membrane-bound vacuoles. The bovine septicemic isolate used in this study expressed the fimbrial adhesion CS31A. To examine the role of CS31A-mediated adherence in invasion and transcytosis of MDCK cell monolayers, a CS31A-deficient mutant was constructed by suicide vector-mediated insertional mutagenesis. Although nonadherent, the mutant showed a level of invasion similar to that of the wild-type parent. E. coli DH5 alpha carrying the cloned CS31A determinant was noninvasive. These findings suggest that expression of CS31A is neither required nor sufficient to mediate invasion. Images PMID:7903284

  17. Glycogen Synthase Kinase 3 (GSK-3) influences epithelial barrier function by regulating Occludin, Claudin-1 and E-cadherin expression

    SciTech Connect

    Severson, Eric A.; Kwon, Mike; Hilgarth, Roland S.; Parkos, Charles A.; Nusrat, Asma

    2010-07-02

    The Apical Junctional Complex (AJC) encompassing the tight junction (TJ) and adherens junction (AJ) plays a pivotal role in regulating epithelial barrier function and epithelial cell proliferative processes through signaling events that remain poorly characterized. A potential regulator of AJC protein expression is Glycogen Synthase Kinase-3 (GSK-3). GSK-3 is a constitutively active kinase that is repressed during epithelial-mesenchymal transition (EMT). In the present study, we report that GSK-3 activity regulates the structure and function of the AJC in polarized model intestinal (SK-CO15) and kidney (Madin-Darby Canine Kidney (MDCK)) epithelial cells. Reduction of GSK-3 activity, either by small molecule inhibitors or siRNA targeting GSK-3 alpha and beta mRNA, resulted in increased permeability to both ions and bulk solutes. Immunofluorescence labeling and immunoblot analyses revealed that the barrier defects correlated with decreased protein expression of AJC transmembrane proteins Occludin, Claudin-1 and E-cadherin without influencing other TJ proteins, Zonula Occludens-1 (ZO-1) and Junctional Adhesion Molecule A (JAM-A). The decrease in Occludin and E-cadherin protein expression correlated with downregulation of the corresponding mRNA levels for these respective proteins following GSK-3 inhibition. These observations implicate an important role of GSK-3 in the regulation of the structure and function of the AJC that is mediated by differential modulation of mRNA transcription of key AJC proteins, Occludin, Claudin-1 and E-cadherin.

  18. AMP-activated protein kinase induces actin cytoskeleton reorganization in epithelial cells

    SciTech Connect

    Miranda, Lisa; Carpentier, Sarah; Platek, Anna; Hussain, Nusrat; Gueuning, Marie-Agnes; Vertommen, Didier; Ozkan, Yurda; Sid, Brice; Hue, Louis; Courtoy, Pierre J.; Rider, Mark H.; Horman, Sandrine

    2010-06-04

    AMP-activated protein kinase (AMPK), a known regulator of cellular and systemic energy balance, is now recognized to control cell division, cell polarity and cell migration, all of which depend on the actin cytoskeleton. Here we report the effects of A769662, a pharmacological activator of AMPK, on cytoskeletal organization and signalling in epithelial Madin-Darby canine kidney (MDCK) cells. We show that AMPK activation induced shortening or radiation of stress fibers, uncoupling from paxillin and predominance of cortical F-actin. In parallel, Rho-kinase downstream targets, namely myosin regulatory light chain and cofilin, were phosphorylated. These effects resembled the morphological changes in MDCK cells exposed to hyperosmotic shock, which led to Ca{sup 2+}-dependent AMPK activation via calmodulin-dependent protein kinase kinase-{beta}(CaMKK{beta}), a known upstream kinase of AMPK. Indeed, hypertonicity-induced AMPK activation was markedly reduced by the STO-609 CaMKK{beta} inhibitor, as was the increase in MLC and cofilin phosphorylation. We suggest that AMPK links osmotic stress to the reorganization of the actin cytoskeleton.

  19. Cell confinement controls centrosome positioning and lumen initiation during epithelial morphogenesis

    PubMed Central

    Rodríguez-Fraticelli, Alejo E.; Auzan, Muriel; Alonso, Miguel A.; Bornens, Michel

    2012-01-01

    Epithelial organ morphogenesis involves sequential acquisition of apicobasal polarity by epithelial cells and development of a functional lumen. In vivo, cells perceive signals from components of the extracellular matrix (ECM), such as laminin and collagens, as well as sense physical conditions, such as matrix stiffness and cell confinement. Alteration of the mechanical properties of the ECM has been shown to promote cell migration and invasion in cancer cells, but the effects on epithelial morphogenesis have not been characterized. We analyzed the effects of cell confinement on lumen morphogenesis using a novel, micropatterned, three-dimensional (3D) Madin-Darby canine kidney cell culture method. We show that cell confinement, by controlling cell spreading, limits peripheral actin contractility and promotes centrosome positioning and lumen initiation after the first cell division. In addition, peripheral actin contractility is mediated by master kinase Par-4/LKB1 via the RhoA–Rho kinase–myosin II pathway, and inhibition of this pathway restores lumen initiation in minimally confined cells. We conclude that cell confinement controls nuclear–centrosomal orientation and lumen initiation during 3D epithelial morphogenesis. PMID:22965908

  20. Mitogen-stimulated and rapamycin-sensitive glucose transporter 12 targeting and functional glucose transport in renal epithelial cells.

    PubMed

    Wilson-O'Brien, Amy L; Dehaan, Carrie L; Rogers, Suzanne

    2008-03-01

    We hypothesized that glucose transporter 12 (GLUT12) is involved in regulation of glucose flux in distal renal tubules in response to elevated glucose. We used the Madin-Darby canine kidney polarized epithelial cell model and neutralizing antibodies to analyze GLUT12 targeting and directional GLUT12-mediated glucose transport. At physiological glucose concentrations, GLUT12 was localized to a perinuclear position. High glucose and serum treatment resulted in GLUT12 localization to the apical membrane. This mitogen-stimulated targeting of GLUT12 was inhibited by rapamycin, the specific inhibitor of mammalian target of rapamycin (mTOR). The functional role of GLUT12 was also examined. We constructed a GLUT12 cDNA containing a c-Myc epitope tag in the fifth exofacial loop. Assays of glucose transport at the apical membrane were performed using Transwell filters. By comparing transport assays in the presence of neutralizing anti-c-Myc monoclonal antibody, we specifically measured GLUT12-mediated glucose transport at the apical surface. GLUT12-mediated glucose transport was mitogen dependent and rapamycin sensitive. Our results implicate mTOR signaling in a novel pathway of glucose transporter protein targeting and glucose transport. Activity of the mTOR pathway has been associated with diabetic kidney disease. Our results provide evidence for a link between GLUT12 protein trafficking, glucose transport and signaling molecules central to the control of metabolic disease processes. PMID:18039784

  1. FSGS3/CD2AP is a barbed-end capping protein that stabilizes actin and strengthens adherens junctions

    PubMed Central

    Brieher, William M.

    2013-01-01

    By combining in vitro reconstitution biochemistry with a cross-linking approach, we have identified focal segmental glomerulosclerosis 3/CD2-associated protein (FSGS3/CD2AP) as a novel actin barbed-end capping protein responsible for actin stability at the adherens junction. FSGS3/CD2AP colocalizes with E-cadherin and α-actinin-4 at the apical junction in polarized Madin-Darby canine kidney (MDCK) cells. Knockdown of FSGS3/CD2AP compromised actin stability and decreased actin accumulation at the adherens junction. Using a novel apparatus to apply mechanical stress to cell–cell junctions, we showed that knockdown of FSGS3/CD2AP compromised adhesive strength, resulting in tearing between cells and disruption of barrier function. Our results reveal a novel function of FSGS3/CD2AP and a previously unrecognized role of barbed-end capping in junctional actin dynamics. Our study underscores the complexity of actin regulation at cell–cell contacts that involves actin activators, inhibitors, and stabilizers to control adhesive strength, epithelial behavior, and permeability barrier integrity. PMID:24322428

  2. BigA is a novel adhesin of Brucella that mediates adhesion to epithelial cells.

    PubMed

    Czibener, Cecilia; Merwaiss, Fernando; Guaimas, Francisco; Del Giudice, Mariela Giselda; Serantes, Diego Armando Rey; Spera, Juan Manuel; Ugalde, Juan Esteban

    2016-04-01

    Adhesion to cells is the initial step in the infectious cycle of basically all pathogenic bacteria, and to do so, microorganisms have evolved surface molecules that target different cellular receptors. Brucella is an intracellular pathogen that infects a wide range of mammals whose virulence is completely dependent on the capacity to replicate in phagocytes. Although much has been done to elucidate how Brucella multiplies in macrophages, we still do not understand how bacteria invade epithelial cells to perform a replicative cycle or what adhesion molecules are involved in the process. We report the identification in Brucella abortus of a novel adhesin that harbours a bacterial immunoglobulin-like domain and demonstrate that this protein is involved in the adhesion to polarized epithelial cells such as the Caco-2 and Madin-Darby canine kidney models targeting the bacteria to the cell-cell interaction membrane. While deletion of the gene significantly reduced adhesion, over-expression dramatically increased it. Addition of the recombinant protein to cells induced cytoskeleton rearrangements and showed that this adhesin targets proteins of the cell-cell interaction membrane in confluent cultures. PMID:26400021

  3. Cd{sup 2+} versus Zn{sup 2+} uptake by the ZIP8 HCO{sub 3}{sup -}-dependent symporter: Kinetics, electrogenicity and trafficking

    SciTech Connect

    Liu Zhiwei; Li Hong; Soleimani, Manoocher; Girijashanker, Kuppuswami; Reed, Jodie M.; He Lei; Dalton, Timothy P.; Nebert, Daniel W.

    2008-01-25

    The mouse Slc39a8 gene encodes the ZIP8 transporter, which has been shown to be a divalent cation/HCO{sub 3}{sup -} symporter. Using ZIP8 cRNA-injected Xenopus oocyte cultures, we show herein that: [a] ZIP8-mediated cadmium (Cd{sup 2+}) and zinc (Zn{sup 2+}) uptake have V{sub max} values of 1.8 {+-} 0.08 and 1.0 {+-} 0.08 pmol/oocyte/h, and K{sub m} values of 0.48 {+-} 0.08 and 0.26 {+-} 0.09 {mu}M, respectively; [b] ZIP8-mediated Cd{sup 2+} uptake is most inhibited by Zn{sup 2+}, second-best inhibited by Cu{sup 2+}, Pb{sup 2+} and Hg{sup 2+}, and not inhibited by Mn{sup 2+} or Fe{sup 2+}; and [c] electrogenicity studies demonstrate an influx of two HCO{sub 3}{sup -} anions per one Cd{sup 2+} (or one Zn{sup 2+}) cation, i.e. electroneutral complexes. Using Madin-Darby canine kidney (MDCK) polarized epithelial cells retrovirally infected with ZIP8 cDNA and tagged with hemagglutinin at the C-terminus, we show that-similar to ZIP4-the ZIP8 eight-transmembrane protein is largely internalized during Zn{sup 2+} homeostasis, but moves predominantly to the cell surface membrane (trafficking) under conditions of Zn{sup 2+} depletion.

  4. Canine lymphoma

    SciTech Connect

    Weller, R.E.

    1986-10-01

    Canine lymphoma has served as the ''workhorse'' for the development of veterinary oncology and as an important animal model for human non-Hodgkins lymphomas. Significant advances have been achieved in understanding the biological behavior of the disease and in its treatment. Although it is unlikely that a cure for lymphoma will be achieved, owners should be encouraged to treat their pets, provided they understand that only prolonged remissions and survivals are likely to result. Cooperative studies, employing large numbers of dogs, are needed to optimize and refine the classification scheme to provide a system with diagnostic and prognostic correlates and derive maximum benefit from therapeutic regimens. Such studies need to be prospective in nature, with a solid statistical base incorporated into their design. Rather than being content with what we have accomplished to date in treatment of canine lymphoma, the opportunity exists for the veterinary profession to make further significant contributions to the understanding and treatment of lymphoma in the dog. 10 refs., 4 tabs.

  5. Canine hyperlipidaemia.

    PubMed

    Xenoulis, P G; Steiner, J M

    2015-10-01

    Hyperlipidaemia refers to an increased concentration of lipids in the blood. Hyperlipidaemia is common in dogs and has recently emerged as an important clinical condition that requires a systematic diagnostic approach and appropriate treatment. Hyperlipidaemia can be either primary or secondary to other diseases. Secondary hyperlipidaemia is the most common form in dogs, and it can be a result of endocrine disorders, pancreatitis, cholestasis, protein-losing nephropathy, obesity, as well as other conditions and the use of certain drugs. Primary hyperlipidaemia is less common in the general canine population but it can be very common within certain breeds. Hypertriglyceridaemia of Miniature Schnauzers is the most common form of primary hyperlipidaemia in dogs but other breeds are also affected. Possible complications of hyperlipidaemia in dogs include pancreatitis, liver disease, atherosclerosis, ocular disease and seizures. Management of primary hyperlipidaemia in dogs is achieved by administration of ultra low-fat diets with or without the administration of lipid lowering drugs such as omega-3 fatty acids, fibrates, niacin and statins. PMID:26456868

  6. A statistical approach to determining criticality of residual host cell DNA.

    PubMed

    Yang, Harry; Wei, Ziping; Schenerman, Mark

    2015-01-01

    We propose a method for determining the criticality of residual host cell DNA, which is characterized through two attributes, namely the size and amount of residual DNA in biopharmaceutical product. By applying a mechanistic modeling approach to the problem, we establish the linkage between residual DNA and product safety measured in terms of immunogenicity, oncogenicity, and infectivity. Such a link makes it possible to establish acceptable ranges of residual DNA size and amount. Application of the method is illustrated through two real-life examples related to a vaccine manufactured in Madin Darby Canine Kidney cell line and a monoclonal antibody using Chinese hamster ovary (CHO) cell line as host cells. PMID:25358029

  7. Cell cytoskeletal conformation under reversible thermal control

    NASA Astrophysics Data System (ADS)

    Chang, Ting-Ya; Yang, Chung-Yao; Liao, Kai-Wei; Andrew Yeh, J.; Cheng, Chao-Min

    2013-12-01

    In order to assess the role of cytoskeletal structure in modulating cell surface topography during cell transformation, we investigated cytoskeletal organization of Madin-Darby canine kidney (MDCK) epithelial cells at different thermal gradients. Specifically, we examined actin polymerization as a function of temperature in a controlled thermal environment. After applying an increase in temperature of 5 °C, we observed fewer actin filaments in the network, as these molecular polymers depolymerized. Partial stress fibers of MDCK cells could be rearranged, but some of them were disrupted irreversibly after a second thermal treatment, and MDCK cells underwent apoptosis at higher temperatures as well.

  8. Dielectric spectroscopy for non-invasive monitoring of epithelial cell differentiation within three-dimensional scaffolds

    NASA Astrophysics Data System (ADS)

    Daoud, Jamal; Asami, Koji; Rosenberg, Lawrence; Tabrizian, Maryam

    2012-08-01

    In this study, we introduce a cellular differentiation cellular model based on dielectric spectroscopy that characterizes epithelial differentiation processes. Non-invasive cellular monitoring was achieved within a three-dimensional microenvironment consisting of a cell-containing collagen I gel seeded onto microfabricated scaffolds. In this proof-of-concept investigation, Madin-Darby canine kidney cells were cultured within microfabricated, geometrically controlled scaffolds and allowed us to differentiate to hollow cyst-like structures. This transformation within the three-dimensional environment is monitored and characterized through dielectric spectroscopy while maintaining cell culture in vitro.

  9. Cysteine mutagenesis to study the structure of claudin-2 paracellular pores.

    PubMed

    Angelow, Susanne; Yu, Alan S L

    2009-05-01

    The structure and transport mechanism of paracellular pores are only poorly understood. Here we describe for the first time how the substituted cysteine accessibility method (SCAM), previously developed to study transmembrane transport, can be applied to analyze the pathway of paracellular ion permeation. Using stable transfected Madin Darby canine kidney type I cells, induced to express claudin-2, we show that paracellular cation transport can be blocked by sulfhydryl-specific methanethiosulfonate (MTS) and that SCAM can be used to identify residues that line paracellular pores. PMID:19538299

  10. Generalized Klein-Kramers equation: solution and application

    NASA Astrophysics Data System (ADS)

    Sau Fa, Kwok; Wang, K. G.

    2013-09-01

    A generalized Klein-Kramers equation based on the continuous time random walk model is investigated. The equation generalizes the ordinary and fractional Klein-Kramers equations. Analytic solutions for the probability density and first two moments (for the force-free case) are obtained, and their dynamic behaviors are investigated in detail. The model is used to describe the cell migration of two migrating transformed renal epithelial Madin-Darby canine kidney (MDCK-F) cell strains: wild-type (NHE+) and NHE-deficient (NHE-) cells. Our theoretical predictions are in good agreement with experimental work in the paper (Dieterich et al 2008 Proc. Nat. Acad. Sci. USA 105 459).

  11. Localization of Impacted Canines

    PubMed Central

    Mehrotra, Praveen; Bhagchandani, Jitendra; Singh, Ashish; Garg, Aarti; Kumar, Snehi; Sharma, Ashish; Yadav, Harsh

    2015-01-01

    Impaction of maxillary canines is a frequently encountered clinical problem. The impaction of canine can be prevented in some situationsif the canine displacement is diagnosed in the early mixed dentition period and this would be extremely useful for the clinician. Hence,it is very important to focus on the means of early diagnosis and interception of this clinical situation. In the present article, the differentmodalities used to diagnose the impacted canine are reviewed with an insight into current 3-D modalities. PMID:25738100

  12. EB1-recruited microtubule +TIP complexes coordinate protrusion dynamics during 3D epithelial remodeling

    PubMed Central

    Gierke, Sarah; Wittmann, Torsten

    2012-01-01

    SUMMARY Background Epithelial remodeling, in which apical-basal polarized cells switch to a migratory phenotype, plays a central role in development and disease of multicellular organisms. Although dynamic microtubules (MTs) are required for directed migration on flat surfaces, how MT dynamics are controlled or contribute to epithelial remodeling in a more physiological three-dimensional (3D) environment is not understood. We use confocal live cell imaging to analyze MT function and dynamics during 3D epithelial morphogenesis and remodeling of polarized Madin-Darby canine kidney (MDCK) epithelial cells that undergo partial epithelial-to-mesenchymal transition (EMT) in response to hepatocyte growth factor (HGF). Results We find that HGF treatment increases MT growth rate before morphological changes are evident, and that large numbers of MTs grow into HGF-induced cell extensions independent of centrosome reorientation. Using lentivirus-mediated shRNA, we demonstrate that EB1, an adaptor protein that mediates recruitment of numerous other +TIP proteins to growing MT plus ends, is required for this HGF-induced MT reorganization. We further show that protrusion and adhesion dynamics are disorganized, and that vesicular trafficking to the tip of HGF-induced cell extensions is disrupted in EB1-depleted cells. Conclusions We conclude that EB1-mediated interactions with growing MTs are important to coordinate cell shape changes and directed migration into the surrounding extracellular matrix during epithelial remodeling in a physiological 3D environment. In contrast, EB1 is not required for the establishment or maintenance of apical-basal cell polarity, suggesting different functions of +TIPs and MTs in different types of cell polarity. PMID:22483942

  13. The exocyst gene Sec10 regulates renal epithelial monolayer homeostasis and apoptotic sensitivity.

    PubMed

    Polgar, Noemi; Lee, Amanda J; Lui, Vanessa H; Napoli, Josephine A; Fogelgren, Ben

    2015-08-01

    The highly conserved exocyst protein complex regulates polarized exocytosis of subsets of secretory vesicles. A previous study reported that shRNA knockdown of an exocyst central subunit, Sec10 (Sec10-KD) in Madin-Darby canine kidney (MDCK) cells disrupted primary cilia assembly and 3D cyst formation. We used three-dimensional collagen cultures of MDCK cells to further investigate the mechanisms by which Sec10 and the exocyst regulate epithelial polarity, morphogenesis, and homeostasis. Sec10-KD cysts initially demonstrated undisturbed lumen formation although later displayed significantly fewer and shorter primary cilia than controls. Later in cystogenesis, control cells maintained normal homeostasis, while Sec10-KD cysts displayed numerous apoptotic cells extruded basally into the collagen matrix. Sec10-KD MDCK cells were also more sensitive to apoptotic triggers than controls. These phenotypes were reversed by restoring Sec10 expression with shRNA-resistant human Sec10. Apico-basal polarity appeared normal in Sec10-KD cysts, whereas mitotic spindle angles differed significantly from controls, suggesting a planar cell polarity defect. In addition, analysis of renal tubules in a newly generated kidney-specific Sec10-knockout mouse model revealed significant defects in primary cilia assembly and in the targeted renal tubules; abnormal epithelial cell extrusion was also observed, supporting our in vitro results. We hypothesize that, in Sec10-KD cells, the disrupted exocyst activity results in increased apoptotic sensitivity through defective primary cilia signaling and that, in combination with an increased basal cell extrusion rate, it affects epithelial barrier integrity and homeostasis. PMID:26040895

  14. Core-glycosylated mucin-like repeats from MUC1 are an apical targeting signal.

    PubMed

    Kinlough, Carol L; Poland, Paul A; Gendler, Sandra J; Mattila, Polly E; Mo, Di; Weisz, Ora A; Hughey, Rebecca P

    2011-11-11

    MUC1 is efficiently delivered to the apical surface of polarized Madin-Darby canine kidney (MDCK) cells by transit through apical recycling endosomes, a route associated with delivery of apical proteins with glycan-dependent targeting signals. However, a role for glycans in MUC1 sorting has not been established. A key feature of MUC1 is a heavily O-glycosylated mucin-like domain with a variable number of nearly perfect tandem repeats and adjacent imperfect repeats. Metabolic labeling, cell surface biotinylation, immobilized lectins, and confocal immunofluorescence microscopy were used to characterize the polarized delivery of MUC1 mutants and chimeras in MDCK cells to identify the apical targeting signal. Both the interleukin-2 receptor α subunit (Tac) and a chimera where the Tac ectodomain replaced that of MUC1 were delivered primarily to the basolateral surface. Attachment of the MUC1 mucin-like domain to the N terminus of Tac enhanced apical but not basolateral delivery when compared with Tac. Conversely, deletions within the mucin-like domain in MUC1 reduced apical but not basolateral delivery when compared with MUC1. In pull-down assays with lectins, we found a notable difference in the presence of core 1 O-glycans, but not poly-N-acetyllactosamine, in apically targeted MUC1 and chimeras when compared with Tac. Consistent with these data, we found no effect on MUC1 targeting when galectin-3, with preference for poly-N-acetyllactosamine, was depleted from polarized MDCK cells. However, we did block the apical targeting activity of the mucin-like repeats when we overexpressed CMP-Neu5Ac:GalNAc-Rα2,6-sialyltransferase-1 to block core O-glycan synthesis. The cumulative data indicate that the core-glycosylated mucin-like repeats of MUC1 constitute an apical targeting signal. PMID:21937430

  15. An acidic cluster in the cytosolic domain of human cytomegalovirus glycoprotein B is a signal for endocytosis from the plasma membrane.

    PubMed

    Tugizov, S; Maidji, E; Xiao, J; Pereira, L

    1999-10-01

    We previously reported that human cytomegalovirus (CMV) glycoprotein B (gB) is transported to apical membranes in CMV-infected polarized retinal pigment epithelial (ARPE-19) cells and in Madin-Darby canine kidney (MDCK) epithelial cells constitutively expressing gB. The cytosolic domain of gB contains a cluster of acidic amino acids, a motif that plays a pivotal role in vectorial trafficking in polarized epithelial cells and may also function as a signal for entry into the endocytic pathway. Here we compared gB internalization and recycling to the plasma membrane in CMV-infected human fibroblasts (HF) and ARPE-19 cells by using antibody-internalization experiments. Immunofluorescence and quantitative assays showed that gB was internalized from the cell surface into clathrin-coated transport vesicles and then recycled to the plasma membrane. gB colocalized with clathrin-coated vesicles containing the transferrin receptor in the early endocytic/recycling pathway, indicating that gB traffics in this pathway. The specific role of the acidic cluster in regulating the sorting of gB-containing vesicles in the early endocytic/recycling pathway was examined in MDCK cells expressing mutated gB derivatives. Immunofluorescence assays showed that derivatives lacking the acidic cluster were impaired in internalization and failed to recycle. These findings, together with our earlier observation that the acidic cluster is a key determinant for targeting gB molecules to apical membranes in epithelial cells, establish that this signal is recognized by cellular proteins that participate in polarized sorting and transport in the early endocytic/recycling pathway. PMID:10482621

  16. An Acidic Cluster in the Cytosolic Domain of Human Cytomegalovirus Glycoprotein B Is a Signal for Endocytosis from the Plasma Membrane

    PubMed Central

    Tugizov, Sharof; Maidji, Ekaterina; Xiao, Jianqiao; Pereira, Lenore

    1999-01-01

    We previously reported that human cytomegalovirus (CMV) glycoprotein B (gB) is transported to apical membranes in CMV-infected polarized retinal pigment epithelial (ARPE-19) cells and in Madin-Darby canine kidney (MDCK) epithelial cells constitutively expressing gB. The cytosolic domain of gB contains a cluster of acidic amino acids, a motif that plays a pivotal role in vectorial trafficking in polarized epithelial cells and may also function as a signal for entry into the endocytic pathway. Here we compared gB internalization and recycling to the plasma membrane in CMV-infected human fibroblasts (HF) and ARPE-19 cells by using antibody-internalization experiments. Immunofluorescence and quantitative assays showed that gB was internalized from the cell surface into clathrin-coated transport vesicles and then recycled to the plasma membrane. gB colocalized with clathrin-coated vesicles containing the transferrin receptor in the early endocytic/recycling pathway, indicating that gB traffics in this pathway. The specific role of the acidic cluster in regulating the sorting of gB-containing vesicles in the early endocytic/recycling pathway was examined in MDCK cells expressing mutated gB derivatives. Immunofluorescence assays showed that derivatives lacking the acidic cluster were impaired in internalization and failed to recycle. These findings, together with our earlier observation that the acidic cluster is a key determinant for targeting gB molecules to apical membranes in epithelial cells, establish that this signal is recognized by cellular proteins that participate in polarized sorting and transport in the early endocytic/recycling pathway. PMID:10482621

  17. A single amino acid in the PB2 gene of influenza A virus is a determinant of host range.

    PubMed Central

    Subbarao, E K; London, W; Murphy, B R

    1993-01-01

    The single gene reassortant virus that derives its PB2 gene from the avian influenza A/Mallard/NY/78 virus and remaining genes from the human influenza A/Los Angeles/2/87 virus exhibits a host range restriction (hr) phenotype characterized by efficient replication in avian tissue and failure to produce plaques in mammalian Madin-Darby canine kidney cells. The hr phenotype is associated with restriction of viral replication in the respiratory tract of squirrel monkeys and humans. To identify the genetic basis of the hr phenotype, we isolated four phenotypic hr mutant viruses that acquired the ability to replicate efficiently in mammalian tissue. Segregational analysis indicated that the loss of the hr phenotype was due to a mutation in the PB2 gene itself. The nucleotide sequences of the PB2 gene of each of the four hr mutants revealed that a single amino acid substitution at position 627 (Glu-->Lys) was responsible for the restoration of the ability of the PB2 single gene reassortant to replicate in Madin-Darby canine kidney cells. Interestingly, the amino acid at position 627 in every avian influenza A virus PB2 protein analyzed to date is glutamic acid, and in every human influenza A virus PB2 protein, it is lysine. Thus, the amino acid at residue 627 of PB2 is an important determinant of host range of influenza A viruses. PMID:8445709

  18. Real-time monitoring of NKCC2 endocytosis by total internal reflection fluorescence (TIRF) microscopy.

    PubMed

    Jaykumar, Ankita Bachhawat; Caceres, Paulo S; Sablaban, Ibrahim; Tannous, Bakhos A; Ortiz, Pablo A

    2016-01-15

    The apical Na-K-2Cl cotransporter (NKCC2) mediates NaCl reabsorption by the thick ascending limb (TAL). The amount of NKCC2 at the apical membrane of TAL cells is determined by exocytic delivery, recycling, and endocytosis. Surface biotinylation allows measurement of NKCC2 endocytosis, but it has low time resolution and does not allow imaging of the dynamic process of endocytosis. We hypothesized that total internal reflection fluorescence (TIRF) microscopy imaging of labeled NKCC2 would allow monitoring of NKCC2 endocytosis in polarized Madin-Darby canine kidney (MDCK) and TAL cells. Thus we generated a NKCC2 construct containing a biotin acceptor domain (BAD) sequence between the transmembrane domains 5 and 6. Once expressed in polarized MDCK or TAL cells, surface NKCC2 was specifically biotinylated by exogenous biotin ligase (BirA). We also demonstrate that expression of a secretory form of BirA in TAL cells induces metabolic biotinylation of NKCC2. Labeling biotinylated surface NKCC2 with fluorescent streptavidin showed that most apical NKCC2 was located within small discrete domains or clusters referred to as "puncta" on the TIRF field. NKCC2 puncta were observed to disappear from the TIRF field, indicating an endocytic event which led to a decrease in the number of surface puncta at a rate of 1.18 ± 0.16%/min in MDCK cells, and a rate 1.09 ± 0.08%/min in TAL cells (n = 5). Treating cells with a cholesterol-chelating agent (methyl-β-cyclodextrin) completely blocked NKCC2 endocytosis. We conclude that TIRF microscopy of labeled NKCC2 allows the dynamic imaging of individual endocytic events at the apical membrane of TAL cells. PMID:26538436

  19. Structural determinants of peripheral O-arylcarbamate FAAH inhibitors render them dual substrates for Abcb1 and Abcg2 and restrict their access to the brain

    PubMed Central

    Moreno-Sanz, Guillermo; Barrera, Borja; Armirotti, Andrea; Bertozzi, Sine M.; Scarpelli, Rita; Bandiera, Tiziano; Prieto, Julio G.; Duranti, Andrea; Tarzia, Giorgio; Merino, Gracia

    2014-01-01

    The blood-brain barrier (BBB) is the main entry route for chemicals into the mammalian central nervous system (CNS). Two transmembrane transporters of the ATP-binding cassette (ABC) family – Breast Cancer Resistance Protein (ABCG2 in humans, Abcg2 in rodents) and P-glycoprotein (ABCB1 in humans, Abcb1 in rodents) – play a key role in mediating this process. Pharmacological and genetic evidence suggests that Abcg2 prevents CNS access to a group of highly potent and selective O-arylcarbamate fatty-acid amidohydrolase (FAAH) inhibitors, which include the compound URB937 (cyclohexylcarbamic acid 3′-carbamoyl-6-hydroxybiphenyl-3-yl ester). To define structure-activity relationships of the interaction of these molecules with Abcg2, in the present study we tested various peripherally restricted and non-restricted O-arylcarbamate FAAH inhibitors for their ability to serve as transport substrates in monolayer cultures of Madin-Darby Canine Kidney-II (MDCKII) cells over-expressing Abcg2. Surprisingly, we found that the majority of compounds tested – even those able to enter the CNS in vivo – were substrates for Abcg2 in vitro. Additional experiments in MDCKII cells overexpressing ABCB1 revealed that only those compounds that were dual substrates for ABCB1 and Abcg2 in vitro were also peripherally restricted in vivo. The extent of such restriction seems to depend upon other physicochemical features of the compounds, in particular the polar surface area. Consistent with these in vitro results, we found that URB937 readily enters the brain in dual knockout mice lacking both Abcg2 and Abcb1, whereas it is either partially or completely excluded from the brain of mice lacking either transporter alone. The results suggest that Abcg2 and Abcb1 act together to restrict the access of URB937 to the CNS. PMID:24993496

  20. Regulation of the Axillary Osmidrosis-Associated ABCC11 Protein Stability by N-Linked Glycosylation: Effect of Glucose Condition

    PubMed Central

    Toyoda, Yu; Takada, Tappei; Miyata, Hiroshi; Ishikawa, Toshihisa; Suzuki, Hiroshi

    2016-01-01

    ATP-binding cassette C11 (ABCC11) is a plasma membrane protein involved in the transport of a variety of lipophilic anions. ABCC11 wild-type is responsible for the high-secretion phenotypes in human apocrine glands, such as that of wet-type ear wax, and the risk of axillary osmidrosis. We have previously reported that mature ABCC11 is a glycoprotein containing two N-linked glycans at Asn838 and Asn844. However, little is known about the role of N-linked glycosylation in the regulation of ABCC11 protein. In the current study, we investigated the effects of N-linked glycosylation on the protein level and localization of ABCC11 using polarized Madin-Darby canine kidney II cells. When the N-linked glycosylation in ABCC11-expressing cells was chemically inhibited by tunicamycin treatment, the maturation of ABCC11 was suppressed and its protein level was significantly decreased. Immunoblotting analyses demonstrated that the protein level of the N-linked glycosylation-deficient mutant (N838Q and N844Q: Q838/844) was about half of the ABCC11 wild-type level. Further biochemical studies with the Q838/844 mutant showed that this glycosylation-deficient ABCC11 was degraded faster than wild-type probably due to the enhancement of the MG132-sensitive protein degradation pathway. Moreover, the incubation of ABCC11 wild-type-expressing cells in a low-glucose condition decreased mature, glycosylated ABCC11, compared with the high-glucose condition. On the other hand, the protein level of the Q838/844 mutant was not affected by glucose condition. These results suggest that N-linked glycosylation is important for the protein stability of ABCC11, and physiological alteration in glucose may affect the ABCC11 protein level and ABCC11-related phenotypes in humans, such as axillary osmidrosis. PMID:27281343

  1. Involvement of intestinal uptake transporters in the absorption of azithromycin and clarithromycin in the rat.

    PubMed

    Garver, Eric; Hugger, Erin D; Shearn, Shawn P; Rao, Anuradha; Dawson, Paul A; Davis, Charles B; Han, Chao

    2008-12-01

    Macrolide antibiotics azithromycin (AZI) and clarithromycin (CLARI) are large molecular weight compounds and are substrates for apically polarized efflux transporters such as P-glycoprotein, which can potentially restrict intestinal absorption. However, despite these undesired physicochemical and biopharmaceutical properties, AZI and CLARI exhibit moderate to excellent p.o. bioavailability in preclinical species and humans. Intestinal uptake transporters, such as organic anion transporting polypeptides (OATPs), can facilitate the uptake of drugs that are substrates and hence increase p.o. absorption. The present study was designed to determine whether the intestinal Oatps are involved in absorption of these macrolides. AZI or CLARI was dosed p.o. to Sprague-Dawley rats after p.o. administration with vehicle or rifamycin SV (RIF), an OATP inhibitor. The p.o. exposures of AZI and CLARI were reduced 65 and 45%, respectively, when coadministered with an optimized RIF regimen. The p.o. RIF had no affect on the total blood clearance of these macrolides and most likely did not cause induction of metabolizing enzymes and/or transporters. Therefore, the results suggest that inhibition of an RIF-sensitive uptake transporter such as Oatp along the rat gastrointestinal tract was responsible for reduced p.o. exposure of AZI and CLARI. In addition, AZI and CLARI caused inhibition of taurocholate uptake in rat Oatp1a5-transfected Madin-Darby canine kidney cell monolayers. The in vitro and in vivo results suggest that the intestinal Oatps are involved in the p.o. absorption of AZI and CLARI in the rat. PMID:18755851

  2. Syntaxin specificity of aquaporins in the inner medullary collecting duct.

    PubMed

    Mistry, Abinash C; Mallick, Rickta; Klein, Janet D; Weimbs, Thomas; Sands, Jeff M; Fröhlich, Otto

    2009-08-01

    Proper targeting of the aquaporin-2 (AQP2) water channel to the collecting duct apical plasma membrane is critical for the urine concentrating mechanism and body water homeostasis. However, the trafficking mechanisms that recruit AQP2 to the plasma membrane are still unclear. Snapin is emerging as an important mediator in the initial interaction of trafficked proteins with target soluble N-ethylmaleimide-sensitive factor attachment protein (SNAP) receptor (t-SNARE) proteins, and this interaction is functionally important for AQP2 regulation. We show that in AQP2-Madin-Darby canine kidney cells subjected to adenoviral-mediated expression of both snapin and syntaxins, the association of AQP2 with both syntaxin-3 and syntaxin-4 is highly enhanced by the presence of snapin. In pull-down studies, snapin detected AQP2, syntaxin-3, syntaxin-4, and SNAP23 from the inner medullary collecting duct. AQP2 transport activity, as probed by AQP2's urea permeability, was greatly enhanced in oocytes that were coinjected with cRNAs of SNARE components (snapin+syntaxin-3+SNAP23) over those injected with AQP2 cRNA alone. It was not enhanced when syntaxin-3 was replaced by syntaxin-4 (snapin+syntaxin-4+SNAP23). On the other hand, the latter combination significantly enhanced the transport activity of the related AQP3 water channel while the presence of syntaxin-3 did not. This AQP-syntaxin interaction agrees with the polarity of these proteins' expression in the inner medullary collecting duct epithelium. Thus our findings suggest a selectivity of interactions between different aquaporin and syntaxin isoforms, and thus in the regulation of AQP2 and AQP3 activities in the plasma membrane. Snapin plays an important role as a linker between the water channel and the t-SNARE complex, leading to the fusion event, and the pairing with specific t-SNAREs is essential for the specificity of membrane recognition and fusion. PMID:19515809

  3. Aqueous extract of Costus arabicus inhibits calcium oxalate crystal growth and adhesion to renal epithelial cells.

    PubMed

    de Cógáin, Mitra R; Linnes, Michael P; Lee, Hyo Jung; Krambeck, Amy E; de Mendonça Uchôa, Julio Cezar; Kim, Sung-Hoon; Lieske, John C

    2015-04-01

    Costus arabicus L. (C. arabicus) is a plant used in Brazilian folk medicine to treat urolithiasis; however, its mechanism of action is unclear. The interaction between calcium oxalate (CaOx) crystals and the renal epithelium is important in calculogenesis, and compounds that modulate this process represent candidate therapeutic agents for stone prevention. Therefore, we assessed the inhibitory activity of C. arabicus on CaOx crystallization and the interaction of CaOx crystals with the renal epithelium. A seeded CaOx monohydrate (COM) crystallization system was used to study the effect of C. arabicus on crystal growth. Madin Darby canine kidney (MDCK) cells were used to study [(14)C] COM crystal adhesion in the presence and absence of an aqueous extract of C. arabicus. Cytotoxicity was assessed using a tetrazolium (MTS) cell proliferation assay. Aqueous extracts of C. arabicus decreased crystal growth in a concentration-dependent fashion. Precoating crystals with C. arabicus extract prevented their adhesion to MDCK cells, while pretreating cells did not show any effect. The extract was non-cytotoxic in concentrations of at least 1 mg/ml, which is likely above concentrations achievable in the urine following oral ingestion and excretion. No inhibitory activity was found in hexane, methyl chloride, n-butanol and ethyl acetate fractions of an ethanol extract of the herb. An aqueous extract of C. arabicus may disrupt calculogenesis by interacting with CaOx crystal surfaces. Activity was present in the aqueous extract; therefore, this agent may be bioavailable when administered orally. Fractionation results suggest that the active agent might be a polar polysaccharide. Further identification and characterization along these lines may be warranted. PMID:25652357

  4. Mutations in the Cytoplasmic Domain of the Newcastle Disease Virus Fusion Protein Confer Hyperfusogenic Phenotypes Modulating Viral Replication and Pathogenicity

    PubMed Central

    Samal, Sweety; Khattar, Sunil K.; Paldurai, Anandan; Palaniyandi, Senthilkumar; Zhu, Xiaoping; Collins, Peter L.

    2013-01-01

    The Newcastle disease virus (NDV) fusion protein (F) mediates fusion of viral and host cell membranes and is a major determinant of NDV pathogenicity. In the present study, we demonstrate the effects of functional properties of F cytoplasmic tail (CT) amino acids on virus replication and pathogenesis. Out of a series of C-terminal deletions in the CT, we were able to rescue mutant viruses lacking two or four residues (rΔ2 and rΔ4). We further rescued viral mutants with individual amino acid substitutions at each of these four terminal residues (rM553A, rK552A, rT551A, and rT550A). In addition, the NDV F CT has two conserved tyrosine residues (Y524 and Y527) and a dileucine motif (LL536-537). In other paramyxoviruses, these residues were shown to affect fusion activity and are central elements in basolateral targeting. The deletion of 2 and 4 CT amino acids and single tyrosine substitution resulted in hyperfusogenic phenotypes and increased viral replication and pathogenesis. We further found that in rY524A and rY527A viruses, disruption of the targeting signals did not reduce the expression on the apical or basolateral surface in polarized Madin-Darby canine kidney cells, whereas in double tyrosine mutant, it was reduced on both the apical and basolateral surfaces. Interestingly, in rL536A and rL537A mutants, the F protein expression was more on the apical than on the basolateral surface, and this effect was more pronounced in the rL537A mutant. We conclude that these wild-type residues in the NDV F CT have an effect on regulating F protein biological functions and thus modulating viral replication and pathogenesis. PMID:23843643

  5. Regulation of the Axillary Osmidrosis-Associated ABCC11 Protein Stability by N-Linked Glycosylation: Effect of Glucose Condition.

    PubMed

    Toyoda, Yu; Takada, Tappei; Miyata, Hiroshi; Ishikawa, Toshihisa; Suzuki, Hiroshi

    2016-01-01

    ATP-binding cassette C11 (ABCC11) is a plasma membrane protein involved in the transport of a variety of lipophilic anions. ABCC11 wild-type is responsible for the high-secretion phenotypes in human apocrine glands, such as that of wet-type ear wax, and the risk of axillary osmidrosis. We have previously reported that mature ABCC11 is a glycoprotein containing two N-linked glycans at Asn838 and Asn844. However, little is known about the role of N-linked glycosylation in the regulation of ABCC11 protein. In the current study, we investigated the effects of N-linked glycosylation on the protein level and localization of ABCC11 using polarized Madin-Darby canine kidney II cells. When the N-linked glycosylation in ABCC11-expressing cells was chemically inhibited by tunicamycin treatment, the maturation of ABCC11 was suppressed and its protein level was significantly decreased. Immunoblotting analyses demonstrated that the protein level of the N-linked glycosylation-deficient mutant (N838Q and N844Q: Q838/844) was about half of the ABCC11 wild-type level. Further biochemical studies with the Q838/844 mutant showed that this glycosylation-deficient ABCC11 was degraded faster than wild-type probably due to the enhancement of the MG132-sensitive protein degradation pathway. Moreover, the incubation of ABCC11 wild-type-expressing cells in a low-glucose condition decreased mature, glycosylated ABCC11, compared with the high-glucose condition. On the other hand, the protein level of the Q838/844 mutant was not affected by glucose condition. These results suggest that N-linked glycosylation is important for the protein stability of ABCC11, and physiological alteration in glucose may affect the ABCC11 protein level and ABCC11-related phenotypes in humans, such as axillary osmidrosis. PMID:27281343

  6. Evaluation of the bioavailability of major withanolides of Withania somnifera using an in vitro absorption model system

    PubMed Central

    Devkar, Santosh T.; Kandhare, Amit D.; Sloley, Brian D.; Jagtap, Suresh D.; Lin, James; Tam, Yun K.; Katyare, Surendra S.; Bodhankar, Subhash L.; Hegde, Mahabaleshwar V.

    2015-01-01

    Withania somnifera (L.) Dunal, shows several pharmacological properties which are attributed mainly to the withanolides present in the root. The efficacy of medicinally active withanolides constituents depends on the absorption and transportation through the intestinal epithelium. We examined these characteristics by employing the Sino-Veda Madin-Darby canine kidney cells culture system, which under in vitro condition shows the absorption characteristics similar to the human intestinal epithelium. Thus, the aim of the present investigation was to assess the bioavailability of individual withanolides. Withanolides were diluted in Hank's buffered saline at a concentration of 2 μg/ml were tested for permeability studies carried out for 1 h duration. Permeability was measured in terms of efflux pump (Peff) in cm/s. Peff values of withanolide A (WN A), withanone (WNN), 1,2-deoxywithastramonolide (1,2 DWM), withanolide B (WN B), withanoside IV-V (WS IV-V), and withaferin A were 4.05 × 10−5, 2.06 × 10−5, 1.97 × 10−5, 1.80 × 10−5, 3.19 × 10−6, 3.03 × 10−6 and 3.30 × 10−7 respectively. In conclusion, the nonpolar and low molecular weight compounds (WN A, WNN, 1,2 DWM, and WN B) were highly permeable. As against this, the glycosylated and polar WS IV and WS V showed low permeability. Surprisingly and paradoxically, the highly biologically active withaferin A was completely impermeable, suggesting that further studies possibly using human epithelial colorectal adenocarcinoma (Caco-2) cells may be needed to delineate the absorption characteristics of withanolides, especially withaferin A. PMID:26605156

  7. Molecular Mechanism of Renal Tubular Secretion of the Antimalarial Drug Chloroquine ▿

    PubMed Central

    Müller, Fabian; König, Jörg; Glaeser, Hartmut; Schmidt, Ingrid; Zolk, Oliver; Fromm, Martin F.; Maas, Renke

    2011-01-01

    The antimalarial drug chloroquine is eliminated to a significant extent by renal tubular secretion. The molecular mechanism of renal chloroquine secretion remains unknown. We hypothesized that organic cation transporter 2 (OCT2) and multidrug and toxin extrusion protein 1 (MATE1), localized in the basolateral and luminal membranes of proximal tubule cells, respectively, are involved in chloroquine transport. The interaction of chloroquine with both transporters was investigated using single-transfected human embryonic kidney 293 (HEK293)-MATE1 cells in uptake experiments and single-transfected Madin-Darby canine kidney II (MDCK)-OCT2 and MDCK-MATE1 cells as well as double-transfected MDCK-OCT2-MATE1 cells grown as polarized monolayers on transwell filters. In HEK293-MATE1 cells, chloroquine competitively inhibited MATE1-mediated metformin uptake (Ki = 2.8 μM). Cellular accumulation of chloroquine was significantly lower (P < 0.001) and transcellular chloroquine transport was significantly increased (P < 0.001) in MDCK-MATE1 and MDCK-OCT2-MATE1 cells compared to vector control cells after basal addition of chloroquine (0.1 to 10 μM). In contrast, no difference in cellular accumulation or transcellular transport of chloroquine was observed between MDCK-OCT2 and vector control cells. In line with an oppositely directed proton gradient acting as a driving force for MATE1, basal-to-apical transport of chloroquine by MDCK-OCT2-MATE1 cells increased with decreasing apical pH from 7.8 to 6.0. Transcellular transport of chloroquine by MDCK-OCT2-MATE1 cells was inhibited by cimetidine, trimethoprim, and amitriptyline. Our data demonstrate that chloroquine is a substrate and potent competitive inhibitor of MATE1, whereas OCT2 seems to play no role in chloroquine uptake. Concomitantly administered MATE1 inhibitors are likely to modify the renal secretion of chloroquine. PMID:21518836

  8. Identification and Functional Characterization of the First Nucleobase Transporter in Mammals

    PubMed Central

    Yamamoto, Syunsuke; Inoue, Katsuhisa; Murata, Tomoaki; Kamigaso, Syunsuke; Yasujima, Tomoya; Maeda, Jun-ya; Yoshida, Yukihiro; Ohta, Kin-ya; Yuasa, Hiroaki

    2010-01-01

    Nucleobases are important compounds that constitute nucleosides and nucleic acids. Although it has long been suggested that specific transporters are involved in their intestinal absorption and uptake in other tissues, none of their molecular entities have been identified in mammals to date. Here we describe identification of rat Slc23a4 as the first sodium-dependent nucleobase transporter (rSNBT1). The mRNA of rSNBT1 was expressed highly and only in the small intestine. When transiently expressed in HEK293 cells, rSNBT1 could transport uracil most efficiently. The transport of uracil mediated by rSNBT1 was sodium-dependent and saturable with a Michaelis constant of 21.2 μm. Thymine, guanine, hypoxanthine, and xanthine were also transported, but adenine was not. It was also suggested by studies of the inhibitory effect on rSNBT1-mediated uracil transport that several nucleobase analogs such as 5-fluorouracil are recognized by rSNBT1, but cytosine and nucleosides are not or only poorly recognized. Furthermore, rSNBT1 fused with green fluorescent protein was mainly localized at the apical membrane, when stably expressed in polarized Madin-Darby canine kidney II cells. These characteristics of rSNBT1 were almost fully in agreement with those of the carrier-mediated transport system involved in intestinal uracil uptake. Therefore, it is likely that rSNBT1 is its molecular entity or at least in part responsible for that. It was also found that the gene orthologous to the rSNBT1 gene is genetically defective in humans. This may have a biological and evolutional meaning in the transport and metabolism of nucleobases. The present study provides novel insights into the specific transport and metabolism of nucleobases and their analogs for therapeutic use. PMID:20042597

  9. VAMP7 Modulates Ciliary Biogenesis in Kidney Cells

    PubMed Central

    Szalinski, Christina M.; Labilloy, Anatália; Bruns, Jennifer R.; Weisz, Ora A.

    2014-01-01

    Epithelial cells elaborate specialized domains that have distinct protein and lipid compositions, including the apical and basolateral surfaces and primary cilia. Maintaining the identity of these domains is required for proper cell function, and requires the efficient and selective SNARE-mediated fusion of vesicles containing newly synthesized and recycling proteins with the proper target membrane. Multiple pathways exist to deliver newly synthesized proteins to the apical surface of kidney cells, and the post-Golgi SNAREs, or VAMPs, involved in these distinct pathways have not been identified. VAMP7 has been implicated in apical protein delivery in other cell types, and we hypothesized that this SNARE would have differential effects on the trafficking of apical proteins known to take distinct routes to the apical surface in kidney cells. VAMP7 expressed in polarized Madin Darby canine kidney cells colocalized primarily with LAMP2-positive compartments, and siRNA-mediated knockdown modulated lysosome size, consistent with the known function of VAMP7 in lysosomal delivery. Surprisingly, VAMP7 knockdown had no effect on apical delivery of numerous cargoes tested, but did decrease the length and frequency of primary cilia. Additionally, VAMP7 knockdown disrupted cystogenesis in cells grown in a three-dimensional basement membrane matrix. The effects of VAMP7 depletion on ciliogenesis and cystogenesis are not directly linked to the disruption of lysosomal function, as cilia lengths and cyst morphology were unaffected in an MDCK lysosomal storage disorder model. Together, our data suggest that VAMP7 plays an essential role in ciliogenesis and lumen formation. To our knowledge, this is the first study implicating an R-SNARE in ciliogenesis and cystogenesis. PMID:24466086

  10. The ABCG2 Efflux Transporter in the Mammary Gland Mediates Veterinary Drug Secretion across the Blood-Milk Barrier into Milk of Dairy Cows.

    PubMed

    Mahnke, Hanna; Ballent, Mariana; Baumann, Sven; Imperiale, Fernanda; von Bergen, Martin; Lanusse, Carlos; Lifschitz, Adrian L; Honscha, Walther; Halwachs, Sandra

    2016-05-01

    In human and mice ATP-binding cassette efflux transporter ABCG2 represents the main route for active drug transport into milk. However, there is no detailed information on the role of ABCG2 in drug secretion and accumulation in milk of dairy animals. We therefore examined ABCG2-mediated drug transport in the bovine mammary gland by parallel pharmacokinetic studies in lactating Jersey cows and in vitro flux studies using the anthelmintic drug monepantel (MNP) as representative bovine ABCG2 (bABCG2) drug substrate. Animals received MNP (Zolvix, Novartis Animal Health Inc.) once (2.5 mg/kg per os) and the concentrations of MNP and the active MNP metabolite MNPSO2were assessed by high-performance liquid chromatography. Compared with the parent drug MNP, we detected higher MNPSO2plasma concentrations (expressed as area under the concentration-versus-time curve). Moreover, we observed MNPSO2excretion into milk of dairy cows with a high milk-to-plasma ratio of 6.75. In mechanistic flux assays, we determined a preferential time-dependent basolateral-to-apical (B > A) MNPSO2transport across polarized Madin-Darby canine kidney II cells-bABCG2 monolayers using liquid chromatography coupled with tandem mass spectrometry analysis. The B > A MNPSO2transport was significantly inhibited by the ABCG2 inhibitor fumitremorgin C in bABCG2- but not in mock-transduced MDCKII cells. Additionally, the antibiotic drug enrofloxacin, the benzimidazole anthelmintic oxfendazole and the macrocyclic lactone anthelmintic moxidectin caused a reduction in the MNPSO2(B > A) net efflux. Altogether, this study indicated that therapeutically relevant drugs like the anthelmintic MNP represent substrates of the bovine mammary ABCG2 transporter and may thereby be actively concentrated in dairy milk. PMID:26956640

  11. Evaluation of the bioavailability of major withanolides of Withania somnifera using an in vitro absorption model system.

    PubMed

    Devkar, Santosh T; Kandhare, Amit D; Sloley, Brian D; Jagtap, Suresh D; Lin, James; Tam, Yun K; Katyare, Surendra S; Bodhankar, Subhash L; Hegde, Mahabaleshwar V

    2015-01-01

    Withania somnifera (L.) Dunal, shows several pharmacological properties which are attributed mainly to the withanolides present in the root. The efficacy of medicinally active withanolides constituents depends on the absorption and transportation through the intestinal epithelium. We examined these characteristics by employing the Sino-Veda Madin-Darby canine kidney cells culture system, which under in vitro condition shows the absorption characteristics similar to the human intestinal epithelium. Thus, the aim of the present investigation was to assess the bioavailability of individual withanolides. Withanolides were diluted in Hank's buffered saline at a concentration of 2 μg/ml were tested for permeability studies carried out for 1 h duration. Permeability was measured in terms of efflux pump (P eff) in cm/s. P eff values of withanolide A (WN A), withanone (WNN), 1,2-deoxywithastramonolide (1,2 DWM), withanolide B (WN B), withanoside IV-V (WS IV-V), and withaferin A were 4.05 × 10(-5), 2.06 × 10(-5), 1.97 × 10(-5), 1.80 × 10(-5), 3.19 × 10(-6), 3.03 × 10(-6) and 3.30 × 10(-7) respectively. In conclusion, the nonpolar and low molecular weight compounds (WN A, WNN, 1,2 DWM, and WN B) were highly permeable. As against this, the glycosylated and polar WS IV and WS V showed low permeability. Surprisingly and paradoxically, the highly biologically active withaferin A was completely impermeable, suggesting that further studies possibly using human epithelial colorectal adenocarcinoma (Caco-2) cells may be needed to delineate the absorption characteristics of withanolides, especially withaferin A. PMID:26605156

  12. The inwardly rectifying potassium channel Kir1.1: development of functional assays to identify and characterize channel inhibitors.

    PubMed

    Felix, John P; Priest, Birgit T; Solly, Kelli; Bailey, Timothy; Brochu, Richard M; Liu, Chou J; Kohler, Martin G; Kiss, Laszlo; Alonso-Galicia, Magdalena; Tang, Haifeng; Pasternak, Alexander; Kaczorowski, Gregory J; Garcia, Maria L

    2012-10-01

    The renal outer medullary potassium (ROMK) channel is a member of the inwardly rectifying family of potassium (Kir) channels. ROMK (Kir1.1) is predominantly expressed in kidney where it plays a major role in the salt reabsorption process. Loss-of-function mutations in the human Kir1.1 channel are associated with antenatal Bartter's syndrome type II, a life-threatening salt and water balance disorder. Heterozygous carriers of Kir1.1 mutations associated with antenatal Bartter's syndrome have reduced blood pressure and a decreased risk of developing hypertension by age 60. These data suggest that Kir1.1 inhibitors could represent novel diuretics for the treatment of hypertension. Because little is known about the molecular pharmacology of Kir1.1 channels, assays that provide a robust, reliable readout of channel activity-while operating in high-capacity mode-are needed. In the present study, we describe high-capacity, 384- and 1,536-well plate, functional thallium flux, and IonWorks electrophysiology assays for the Kir1.1 channel that fulfill these criteria. In addition, 96-well (86)Rb(+) flux assays were established that can operate in the presence of 100% serum, and can provide an indication of the effect of a serum shift on compound potencies. The ability to grow Madin-Darby canine kidney cells expressing Kir1.1 in Transwell supports provides a polarized cell system that can be used to study the mechanism of Kir1.1 inhibition by different agents. All these functional Kir1.1 assays together can play an important role in supporting different aspects of drug development efforts during lead identification and/or optimization. PMID:22881347

  13. Regulation of Epithelial-to-Mesenchymal Transition Using Biomimetic Fibrous Scaffolds.

    PubMed

    Ravikrishnan, Anitha; Ozdemir, Tugba; Bah, Mohamed; Baskerville, Karen A; Shah, S Ismat; Rajasekaran, Ayyappan K; Jia, Xinqiao

    2016-07-20

    Epithelial-to-mesenchymal transition (EMT) is a well-studied biological process that takes place during embryogenesis, carcinogenesis, and tissue fibrosis. During EMT, the polarized epithelial cells with a cuboidal architecture adopt an elongated fibroblast-like morphology. This process is accompanied by the expression of many EMT-specific molecular markers. Although the molecular mechanism leading to EMT has been well-established, the effects of matrix topography and microstructure have not been clearly elucidated. Synthetic scaffolds mimicking the meshlike structure of the basement membrane with an average fiber diameter of 0.5 and 5 μm were produced via the electrospinning of poly(ε-caprolactone) (PCL) and were used to test the significance of fiber diameter on EMT. Cell-adhesive peptide motifs were conjugated to the fiber surface to facilitate cell attachment. Madin-Darby Canine Kidney (MDCK) cells grown on these substrates showed distinct phenotypes. On 0.5 μm substrates, cells grew as compact colonies with an epithelial phenotype. On 5 μm scaffolds, cells were more individually dispersed and appeared more fibroblastic. Upon the addition of hepatocyte growth factor (HGF), an EMT inducer, cells grown on the 0.5 μm scaffold underwent pronounced scattering, as evidenced by the alteration of cell morphology, localization of focal adhesion complex, weakening of cell-cell adhesion, and up-regulation of mesenchymal markers. In contrast, HGF did not induce a pronounced scattering of MDCK cells cultured on the 5.0 μm scaffold. Collectively, our results show that the alteration of the fiber diameter of proteins found in the basement membrane may create enough disturbances in epithelial organization and scattering that might have important implications in disease progression. PMID:27322677

  14. Lymphocytes accelerate epithelial tight junction assembly: role of AMP-activated protein kinase (AMPK).

    PubMed

    Tang, Xiao Xiao; Chen, Hao; Yu, Sidney; Zhang, Li; Caplan, Michael J; Chan, Hsiao Chang

    2010-01-01

    The tight junctions (TJs), characteristically located at the apicolateral borders of adjacent epithelial cells, are required for the proper formation of epithelial cell polarity as well as for sustaining the mucosal barrier to the external environment. The observation that lymphocytes are recruited by epithelial cells to the sites of infection [1] suggests that they may play a role in the modulation of epithelial barrier function and thus contribute to host defense. To test the ability of lymphocytes to modulate tight junction assembly in epithelial cells, we set up a lymphocyte-epithelial cell co-culture system, in which Madin-Darby canine kidney (MDCK) cells, a well-established model cell line for studying epithelial TJ assembly [2], were co-cultured with mouse lymphocytes to mimic an infection state. In a typical calcium switch experiment, the TJ assembly in co-culture was found to be accelerated compared to that in MDCK cells alone. This accelaration was found to be mediated by AMP-activated protein kinase (AMPK). AMPK activation was independent of changes in cellular ATP levels but it was found to be activated by the pro-inflammatory cytokine TNF-alpha. Forced suppression of AMPK, either with a chemical inhibitor or by knockdown, abrogated the accelerating effect of lymphocytes on TJ formation. Similar results were also observed in a co-culture with lymphocytes and Calu-3 human airway epithelial cells, suggesting that the activation of AMPK may be a general mechanism underlying lymphocyte-accelerated TJ assembly in different epithelia. These results suggest that signals from lymphocytes, such as cytokines, facilitate TJ assembly in epithelial cells via the activation of AMPK. PMID:20808811

  15. The microenvironmental determinants for kidney epithelial cyst morphogenesis

    PubMed Central

    Guo, Qiusha; Xia, Bing; Moshiach, Simon; Xu, Congfeng; Jiang, Yongde; Chen, Yuanjian; Sun, Yao; Lahti, Jill M.; Zhang, Xin A.

    2011-01-01

    Although epithelial morphogenesis is tightly controlled by intrinsic genetic programs, the microenvironment in which epithelial cells proliferate and differentiate also contributes to the morphogenetic process. The roles of the physical microenvironment in epithelial morphogenesis, however, have not been well dissected. In this study, we assessed the impact of the microenvironment on epithelial cyst formation, which often marks the beginning or end step of morphogenesis of epithelial tissues and the pathological characteristic of some diseases. Previous studies have demonstrated that Madin-Darby canine kidney (MDCK) epithelial cells form cysts when grown in a three-dimensional (3D) extracellullar matrix (ECM) environment. We have now further demonstrated that the presence of ECM in the 3D scaffold is required for the formation of properly polarized cysts. Also, we have found that the full interface of epithelial cells with the ECM environment (in-3D) is not essential for cyst formation, since partial contact (on-3D) is sufficient to induce cystogenesis. In addition, we have defined the minimal ECM environment or the physical threshold for cystogenesis under the on-3D condition. Only above the threshold can the morphological cues from the ECM environment induce cyst formation. Moreover, cyst formation under the on-3D condition described in this study actually defines a novel and more feasible model to analyze in vitro morphogenesis. Finally, we have found that, during cystogenesis, MDCK cells generate basal microprotrusions and produce vesicle-like structures to the basal extracellular space, which are specific to and correlated with cyst formation. For the first time, we have systematically elucidated the microenvironmental determinants for epithelial cystogenesis. PMID:18191498

  16. Vaccines for Canine Leishmaniasis

    PubMed Central

    Foroughi-Parvar, Faeze; Hatam, Gholamreza

    2014-01-01

    Leishmania infantum is the obligatory intracellular parasite of mammalian macrophages and causes zoonotic visceral leishmaniasis (ZVL). The presence of infected dogs as the main reservoir host of ZVL is regarded as the most important potential risk for human infection. Thus the prevention of canine visceral leishmaniasis (CVL) is essential to stop the current increase of the Mediterranean visceral leishmaniasis. Recently considerable advances in achieving protective immunization of dogs and several important attempts for achieving an effective vaccine against CVL lead to attracting the scientists trust in its important role for eradication of ZVL. This paper highlights the recent advances in vaccination against canine visceral leishmaniasis from 2007 until now. PMID:25628897

  17. 9 CFR 113.305 - Canine Hepatitis and Canine Adenovirus Type 2 Vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Canine Hepatitis and Canine Adenovirus... STANDARD REQUIREMENTS Live Virus Vaccines § 113.305 Canine Hepatitis and Canine Adenovirus Type 2 Vaccine. Canine Hepatitis Vaccine and Canine Adenovirus Type 2 Vaccine shall be prepared from virus-bearing...

  18. 9 CFR 113.202 - Canine Hepatitis and Canine Adenovirus Type 2 Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Canine Hepatitis and Canine Adenovirus...; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.202 Canine Hepatitis and Canine Adenovirus Type 2 Vaccine, Killed Virus. Canine Hepatitis and Canine Adenovirus Type 2 Vaccine, Killed...

  19. 9 CFR 113.305 - Canine Hepatitis and Canine Adenovirus Type 2 Vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Canine Hepatitis and Canine Adenovirus... STANDARD REQUIREMENTS Live Virus Vaccines § 113.305 Canine Hepatitis and Canine Adenovirus Type 2 Vaccine. Canine Hepatitis Vaccine and Canine Adenovirus Type 2 Vaccine shall be prepared from virus-bearing...

  20. 9 CFR 113.202 - Canine Hepatitis and Canine Adenovirus Type 2 Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Canine Hepatitis and Canine Adenovirus...; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.202 Canine Hepatitis and Canine Adenovirus Type 2 Vaccine, Killed Virus. Canine Hepatitis and Canine Adenovirus Type 2 Vaccine, Killed...

  1. Vaccines for Canine Leishmaniasis

    PubMed Central

    Palatnik-de-Sousa, Clarisa B.

    2012-01-01

    Leishmaniasis is the third most important vector-borne disease worldwide. Visceral leishmaniasis (VL) is a severe and frequently lethal protozoan disease of increasing incidence and severity due to infected human and dog migration, new geographical distribution of the insect due to global warming, coinfection with immunosuppressive diseases, and poverty. The disease is an anthroponosis in India and Central Africa and a canid zoonosis (ZVL) in the Americas, the Middle East, Central Asia, China, and the Mediterranean. The ZVL epidemic has been controlled by one or more measures including the culling of infected dogs, treatment of human cases, and insecticidal treatment of homes and dogs. However, the use of vaccines is considered the most cost–effective control tool for human and canine disease. Since the severity of the disease is related to the generation of T-cell immunosuppression, effective vaccines should be capable of sustaining or enhancing the T-cell immunity. In this review we summarize the clinical and parasitological characteristics of ZVL with special focus on the cellular and humoral canine immune response and review state-of-the-art vaccine development against human and canine VL. Experimental vaccination against leishmaniasis has evolved from the practice of leishmanization with living parasites to vaccination with crude lysates, native parasite extracts to recombinant and DNA vaccination. Although more than 30 defined vaccines have been studied in laboratory models no human formulation has been licensed so far; however three second-generation canine vaccines have already been registered. As expected for a zoonotic disease, the recent preventive vaccination of dogs in Brazil has led to a reduction in the incidence of canine and human disease. The recent identification of several Leishmania proteins with T-cell epitopes anticipates development of a multiprotein vaccine that will be capable of protecting both humans and dogs against VL. PMID:22566950

  2. The Canine Oral Microbiome

    PubMed Central

    Dewhirst, Floyd E.; Klein, Erin A.; Thompson, Emily C.; Blanton, Jessica M.; Chen, Tsute; Milella, Lisa; Buckley, Catherine M. F.; Davis, Ian J.; Bennett, Marie-Lousie; Marshall-Jones, Zoe V.

    2012-01-01

    Determining the bacterial composition of the canine oral microbiome is of interest for two primary reasons. First, while the human oral microbiome has been well studied using molecular techniques, the oral microbiomes of other mammals have not been studied in equal depth using culture independent methods. This study allows a comparison of the number of bacterial taxa, based on 16S rRNA-gene sequence comparison, shared between humans and dogs, two divergent mammalian species. Second, canine oral bacteria are of interest to veterinary and human medical communities for understanding their roles in health and infectious diseases. The bacteria involved are mostly unnamed and not linked by 16S rRNA-gene sequence identity to a taxonomic scheme. This manuscript describes the analysis of 5,958 16S rRNA-gene sequences from 65 clone libraries. Full length 16S rRNA reference sequences have been obtained for 353 canine bacterial taxa, which were placed in 14 bacterial phyla, 23 classes, 37 orders, 66 families, and 148 genera. Eighty percent of the taxa are currently unnamed. The bacterial taxa identified in dogs are markedly different from those of humans with only 16.4% of oral taxa are shared between dogs and humans based on a 98.5% 16S rRNA sequence similarity cutoff. This indicates that there is a large divergence in the bacteria comprising the oral microbiomes of divergent mammalian species. The historic practice of identifying animal associated bacteria based on phenotypic similarities to human bacteria is generally invalid. This report describes the diversity of the canine oral microbiome and provides a provisional 16S rRNA based taxonomic scheme for naming and identifying unnamed canine bacterial taxa. PMID:22558330

  3. Canine degenerative myelopathy.

    PubMed

    Coates, Joan R; Wininger, Fred A

    2010-09-01

    Canine degenerative myelopathy (DM) is an adult-onset fatal neurodegenerative disease that occurs in many breeds. The initial upper motor neuron spastic paraparesis and general proprioceptive ataxia in the pelvic limbs progress to a flaccid lower motor neuron tetraparesis. Recently, a missense mutation in the superoxide dismutase 1 (SOD1) gene was found to be a risk factor for DM, suggesting that DM is similar to some forms of human amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease). This article reviews the current knowledge of canine DM with regard to its signalment, clinical spectrum, diagnostic approach, and treatment. The implications of the SOD1 mutation on both diseases are discussed, comparing pathogenic mechanisms while conveying perspectives to translational medicine. PMID:20732599

  4. Control of canine distemper.

    PubMed

    Chappuis, G

    1995-05-01

    Control of canine distemper can realistically only be achieved by the use of vaccination. The types of vaccine in current use are described, together with some of the problems encountered such as interference by maternal antibodies, and usage in species other than dogs. Modified live viral vaccines, as used for more than thirty years, have proved very effective. Nevertheless there is scope for some improvement in vaccine efficacy and recent developments in genetic recombinant methods are described. PMID:8588329

  5. Canine ehrlichiosis in Connecticut.

    PubMed Central

    Magnarelli, L A; Litwin, H J; Holland, C J; Anderson, J F; Ristic, M

    1990-01-01

    The first case of canine ehrlichiosis in Connecticut is reported. A female Brittany spaniel from Milford presented with lethargy, anorexia, fever, petechiae, splenomegaly, thrombocytopenia, anemia, elevated serum alkaline phosphatase, lymphopenia, and hypoalbuminemia. Serologic analysis revealed antibodies to Ehrlichia canis (titer, 1:2,560). This documents a more northern geographic distribution in the United States for this infectious agent than had previously been suspected. PMID:2312682

  6. American canine hepatozoonosis.

    PubMed

    Panciera, R J; Ewing, S A

    2003-06-01

    American canine hepatozoonosis is an emerging, tick-transmitted infection of domestic dogs caused by a recently recognized species of apicomplexan parasite, Hepatozoon americanum. The known definitive host of the protozoan is the Gulf Coast tick, Amblyomma maculatum. Presently recognized intermediate hosts include the domestic dog and the coyote, Canis latrans. Laboratory-reared larval or nymphal A. maculatum can be infected readily by feeding to repletion on a parasitemic intermediate host; sporogony requires 35-40 days. Transmission of infection to the dog has been produced experimentally by oral administration of mature oocysts or oocyst-containing ticks. Canine disease follows experimental exposure in 4-6 weeks and is characterized by systemic illness, extreme neutrophilic leukocytosis, muscle and bone pain, and proliferation of periosteal bone. Histopathological findings include multifocal skeletal and cardiac myositis associated with escape of mature merozoites from within the host-cell environment. There is also rapid onset of periosteal activation and osteogenesis and, less frequently, glomerulopathy and amyloidosis. Sequential stages of development of H. americanum in both the dog and the tick have been elucidated. Gamonts potentially infectious to ticks have been observed in peripheral blood leukocytes of the dog in as few as 28 days after exposure to oocysts. Young coyotes experimentally exposed to a canine strain of H. americanum acquired disease indistinguishable from that of similarly exposed young dogs. PMID:12885206

  7. Canine mast cell tumors.

    PubMed

    Macy, D W

    1985-07-01

    Despite the fact that the mast cell tumor is a common neoplasm of the dog, we still have only a meager understanding of its etiology and biologic behavior. Many of the published recommendations for treatment are based on opinion rather than facts derived from careful studies and should be viewed with some skepticism. Because of the infrequent occurrence of this tumor in man, only a limited amount of help can be expected from human oncologists; therefore, burden of responsibility for progress in predicting behavior and developing treatment effective for canine mast cell tumors must fall on the shoulders of the veterinary profession. PMID:3929444

  8. Brazilian canine hepatozoonosis.

    PubMed

    O'Dwyer, Lucia Helena

    2011-01-01

    The genus Hepatozoon includes hundreds of species that infect birds, reptiles, amphibians and mammals, in all continents with tropical and subtropical climates. Two species have been described in domestic dogs: H. canis, reported in Europe, Asia, Africa, South America and the United States; and H. americanum, which so far has only been diagnosed in the United States. In Brazil, the only species found infecting dogs is H. canis. The objective of this review was to detail some aspects of canine hepatozoonosis, caused by H. canis, and the main points of its biology, transmission, pathogenicity, symptoms, epidemiology and diagnostic methods, with emphasis on research developed in Brazil. PMID:21961746

  9. Absence of canine papillomavirus sequences in canine mammary tumours.

    PubMed

    Sardon, D; Blundell, R; Burrai, G P; Alberti, A; Tore, G; Passino, E Sanna; Antuofermo, E

    2015-01-01

    Human papillomaviruses (PVs) are found in human breast cancer tissue; however, it remains controversial as to whether these viruses play a role in the aetiology of this tumour. There has been minimal study of whether PVs are found in normal or abnormal mammary glands of animals. The present study investigated whether a PV sequence could be found in the mammary glands of 33 female dogs by rolling circle amplification and polymerase chain reaction. No PV DNA was found in normal or neoplastic canine mammary tissues, suggesting that canine PVs are probably not involved in the pathogenesis of canine mammary neoplasia. PMID:25435511

  10. Canine rickettsial infections.

    PubMed

    Stiles, J

    2000-09-01

    Dogs that live in tick-infested areas are at risk for contracting rickettsial infections. Clinical signs associated with ehrlichiosis or Rocky Mountain spotted fever may be dramatic or mild. Clinicians must consider the possibility of rickettsial diseases to request laboratory tests that will permit a proper diagnosis. Specific antimicrobial therapy usually brings about clinical improvement, although some dogs may not be cleared of rickettsial organisms, even with prolonged treatment. A small percentage of dogs die of rickettsial infections, either in the acute stage or owing to chronic bone marrow suppression and generalized debilitation. Ocular lesions are an important clinical sign in canine rickettsial infections and may aid the clinician in making a diagnosis and monitoring response to therapy. PMID:11033879

  11. Canine cutaneous leishmaniasis.

    PubMed

    Sasani, F; Javanbakht, J; Samani, R; Shirani, D

    2016-03-01

    Canine cutaneous leishmaniasis (CCL) is a significant veterinary problem. Infected dogs also serve as parasite reservoirs and contribute to human transmission of cutaneous leishmaniasis. Histologically, the lesions were nodular to diffuse interstitial granulomatous dermatitis with histiocytic pseudorosettes together with numerous amastigotes within macrophages and occasionally within the interstitium. Organisms were often contained within clear and intracellular vacuoles. The other inflammatory cells, which were present in the biopsies of the Leishmania-infected dog, were lymphocytes and plasma cells. The histopathology results emphasized the role of dog, particularly asymptomatic dog, as reservoirs for CCL because of the high cutaneous parasite loads. These results may help to explain the maintenance of high transmission rates and numbers of CCL cases in endemic urban regions. PMID:27065598

  12. Knockdown of Sec6 improves cell-cell adhesion by increasing α-E-catenin in oral cancer cells.

    PubMed

    Tanaka, Toshiaki; Iino, Mituyoshi; Goto, Kaoru

    2012-03-23

    The Sec6/8 complex is essential for specific exocytic sites on the plasma membrane and contributes to membrane growth in mammalian cells. In Madin-Darby canine kidney (MDCK) cells, E-cadherin and nectin-based adhesion complexes recruit the Sec6/8 complex to intercellular contacts. However, in cancer cells, the relationship between the Sec6/8 complex and the cell-cell adhesion proteins remains obscure. We demonstrate that the expression of α-E-catenin is increased by Sec6 siRNAs, and E-cadherin and β-catenin localize mainly at the cell-cell contact region in HSC3 cells, which were transfected with Sec6 siRNA. PMID:22381337

  13. Bactericidal effects of antimicrobial agents on epithelial cell-associated Pseudomonas aeruginosa.

    PubMed

    Hirakata, Yoichi; Yano, Hisakazu; Arai, Kazuaki; Kitagawa, Miho; Hatta, Masumitsu; Kunishima, Hiroyuki; Kaku, Mitsuo

    2012-06-01

    It is not clear whether antipseudomonal agents can kill cell-associated bacteria within a short time. Madin-Darby canine kidney (MDCK) and A549 cells were infected with Pseudomonas aeruginosa ATCC 27853 and PAO1 and the bactericidal activity of ceftazidime, imipenem, meropenem, gentamicin, and ciprofloxacin against the organisms was investigated. In both MDCK and A549 cells, β-lactams could not kill epithelial cell-associated bacteria within 2 h. Gentamicin at concentrations ≤32 μg/ml killed more than 99% of epithelial cell-associated bacteria. Ciprofloxacin at 0.5 μg/ml killed more than 99.9% of MDCK cell-associated bacteria. Ciprofloxacin has the strongest and most rapid bactericidal activity against epithelial cell-associated bacteria, which may be explained by the combination of potent in-vitro bactericidal activity and high penetration ability into epithelial cells. PMID:22116462

  14. Synthesis and antiviral activity of 5'-deoxypyrazofurin.

    PubMed

    Chen, X; Schneller, S W; Ikeda, S; Snoeck, R; Andrei, G; Balzarini, J; De Clercq, E

    1993-11-12

    In searching for derivatives of pyrazofurin that could display antiviral properties by means that do not require C-5' phosphorylation, 5'-deoxypyrazofurin (3) has been synthesized in six steps from methyl5-deoxy-2,3-O-isopropylidene-beta-D-ribofuranoside (4). Compound 3 was evaluated for antiviral activity against a large number of viruses including herpes-, pox-, myxo-, toga-, arena-, rhabdo-, picorna-,reo-, and retroviruses. Compound 3 proved active against respiratory syncytial virus (in HeLa cells), vaccinia virus (in embryonic skin-muscle fibroblast cells), vesicular stomatitis virus (in HeLa cells), and influenza A virus (in Madin-Darby canine kidney cells) at concentrations (ranging from 4 to 20 micrograms/mL) that were nontoxic to the confluent host cell cultures. PMID:8246242

  15. Short communication: antiviral activity of subcritical water extract of Brassica juncea against influenza virus A/H1N1 in nonfat milk.

    PubMed

    Lee, N-K; Lee, J-H; Lim, S-M; Lee, K A; Kim, Y B; Chang, P-S; Paik, H-D

    2014-09-01

    Subcritical water extract (SWE) of Brassica juncea was studied for antiviral effects against influenza virus A/H1N1 and for the possibility of application as a nonfat milk supplement for use as an "antiviral food." At maximum nontoxic concentrations, SWE had higher antiviral activity against influenza virus A/H1N1 than n-hexane, ethanol, or hot water (80°C) extracts. Addition of 0.5mg/mL of B. juncea SWE to culture medium led to 50.35% cell viability (% antiviral activity) for Madin-Darby canine kidney cells infected with influenza virus A/H1N1. Nonfat milk supplemented with 0.28mg/mL of B. juncea SWE showed 39.62% antiviral activity against influenza virus A/H1N1. Thus, the use of B. juncea SWE as a food supplement might aid in protection from influenza viral infection. PMID:25022686

  16. Comparison of large-scale mammalian cell culture systems with egg culture for the production of influenza virus A vaccine strains.

    PubMed

    Tree, J A; Richardson, C; Fooks, A R; Clegg, J C; Looby, D

    2001-05-14

    Different types of microcarriers were assessed for the large-scale culture of influenza virus in the Madin-Darby canine kidney (MDCK) cells. Both porous and solid carriers were examined. A higher titre of influenza A/PR8/34 virus was recovered from cultures using solid (1.3x10(9) PFU per ml) rather than porous carriers (4.0x10(8) PFU per ml). High titres of virus (1.0x10(9) PFU per ml) were also obtained from roller bottle cultures of MDCK cells and the traditional culture technique using embryonated hens' eggs (3.9x10(9) PFU per ml). We found that solid carriers composed of dextran with a positive charge are the most suitable carriers for the large-scale growth of influenza A virus in MDCK cells using serum-free media. PMID:11348709

  17. Inhibitors of influenza viruses replication: a patent evaluation (WO2013019828).

    PubMed

    Xie, Yuanchao; Song, Weiguo; Xiao, Weidong; Gu, Changjuan; Xu, Wenfang

    2013-11-01

    A series of compounds incorporating two aromatic heterocycles were prepared as inhibitors of influenza virus replication in the patent. Some of them presented potent activity against influenza virus in Madin-Darby canine kidney (MDCK) cells and in influenza therapeutic mouse model. These compounds in the patent were also defined to be pharmaceutically acceptable salts and pharmaceutical compositions that were claimed to be useful for treating influenza. In view of the threat of influenza pandemic, it is necessary to discover new anti-influenza drugs. Although there is a lack of essential biological data and the molecular mechanisms are not clear, these compounds with potent antiviral activity stand for a new type of anti-influenza agents and deserve further studies. PMID:23967861

  18. Anti-H5N1 virus flavonoids from Capparis sinaica Veill.

    PubMed

    Ibrahim, Amany K; Youssef, Ahmed I; Arafa, Abdel Satar; Ahmed, Safwat A

    2013-01-01

    Methanolic extract of Capparis sinaica Veill was tested for its in vitro antiviral activity against highly pathogenic avian influenza strain H5N1 using plaque inhibition assay in Madin-Darby canine kidney. The results indicated that the extract possessed potent antiviral activity (100% inhibition at the concentration of 1 μg/ml). Based on this result, C. sinaica Veill was selected for further study by applying bioactivity-guided fractionation to isolate its antiviral principles. The fractions eluted with EtOAc and 25% MeOH in EtOAc were found to hold the antiviral activity. Further chromatographic separation of the fractions holding the antiviral activity led to the isolation of quercetin (1), isoquercetin (2) and rutin (3) for the first time from this species. The isolates showed reduction in the virus titre by 68.13%, 79.66% and 73.22% inhibition at a concentration of 1 ng/ml, respectively. PMID:23651316

  19. Resistance of ovine, caprine and bovine endothelial cells to Clostridium perfringens type D epsilon toxin in vitro.

    PubMed

    Uzal, F A; Rolfe, B E; Smith, N J; Thomas, A C; Kelly, W R

    1999-08-01

    Ovine, caprine and bovine endothelial cells were grown in vitro and challenged with Clostridium perfringens type D epsilon toxin to compare their susceptibility to this toxin. Madin Darby canine kidney (MDCK) cells, which are known to be susceptible to epsilon toxin, were used as a positive control. No morphological alterations were observed in any of the endothelial cell cultures tested, even after challenging with doses as high as 1200 MLD50/ml of epsilon toxin. MDCK cells showed contour rounding and nuclear condensation as early as 30 min after exposure to 100 MLD50/ml of epsilon toxin and after 60 min of exposure to 12.5 MLD50/ml of the same toxin. All the MDCK cells were dead after 3 h of exposure to all concentrations of epsilon toxin. The results indicate that ovine, caprine and bovine endothelial cells are not morphologically responsive to the action of epsilon toxin in vitro. PMID:10493114

  20. BRAF Mutations in Canine Cancers

    PubMed Central

    Mochizuki, Hiroyuki; Kennedy, Katherine; Shapiro, Susan G.; Breen, Matthew

    2015-01-01

    Activating mutations of the BRAF gene lead to constitutive activation of the MAPK pathway. Although many human cancers carry the mutated BRAF gene, this mutation has not yet been characterized in canine cancers. As human and canine cancers share molecular abnormalities, we hypothesized that BRAF gene mutations also exist in canine cancers. To test this hypothesis, we sequenced the exon 15 of BRAF, mutation hot spot of the gene, in 667 canine primary tumors and 38 control tissues. Sequencing analysis revealed that a single nucleotide T to A transversion at nucleotide 1349 occurred in 64 primary tumors (9.6%), with particularly high frequency in prostatic carcinoma (20/25, 80%) and urothelial carcinoma (30/45, 67%). This mutation results in the amino acid substitution of glutamic acid for valine at codon 450 (V450E) of canine BRAF, corresponding to the most common BRAF mutation in human cancer, V600E. The evolutional conservation of the BRAF V600E mutation highlights the importance of MAPK pathway activation in neoplasia and may offer opportunity for molecular diagnostics and targeted therapeutics for dogs bearing BRAF-mutated cancers. PMID:26053201

  1. Canine leishmaniosis in South America

    PubMed Central

    Dantas-Torres, Filipe

    2009-01-01

    Canine leishmaniosis is widespread in South America, where a number of Leishmania species have been isolated or molecularly characterised from dogs. Most cases of canine leishmaniosis are caused by Leishmania infantum (syn. Leishmania chagasi) and Leishmania braziliensis. The only well-established vector of Leishmania parasites to dogs in South America is Lutzomyia longipalpis, the main vector of L. infantum, but many other phlebotomine sandfly species might be involved. For quite some time, canine leishmaniosis has been regarded as a rural disease, but nowadays it is well-established in large urbanised areas. Serological investigations reveal that the prevalence of anti-Leishmania antibodies in dogs might reach more than 50%, being as high as 75% in highly endemic foci. Many aspects related to the epidemiology of canine leishmaniosis (e.g., factors increasing the risk disease development) in some South American countries other than Brazil are poorly understood and should be further studied. A better understanding of the epidemiology of canine leishmaniosis in South America would be helpful to design sustainable control and prevention strategies against Leishmania infection in both dogs and humans. PMID:19426440

  2. Sodium-Calcium Exchanger 1 Regulates Epithelial Cell Migration via Calcium-dependent Extracellular Signal-regulated Kinase Signaling*

    PubMed Central

    Balasubramaniam, Sona Lakshme; Gopalakrishnapillai, Anilkumar; Gangadharan, Vimal; Duncan, Randall L.; Barwe, Sonali P.

    2015-01-01

    Na+/Ca2+ exchanger-1 (NCX1) is a major calcium extrusion mechanism in renal epithelial cells enabling the efflux of one Ca2+ ion and the influx of three Na+ ions. The gradient for this exchange activity is provided by Na,K-ATPase, a hetero-oligomer consisting of a catalytic α-subunit and a regulatory β-subunit (Na,K-β) that also functions as a motility and tumor suppressor. We showed earlier that mice with heart-specific ablation (KO) of Na,K-β had a specific reduction in NCX1 protein and were ouabain-insensitive. Here, we demonstrate that Na,K-β associates with NCX1 and regulates its localization to the cell surface. Madin-Darby canine kidney cells with Na,K-β knockdown have reduced NCX1 protein and function accompanied by 2.1-fold increase in free intracellular calcium and a corresponding increase in the rate of cell migration. Increased intracellular calcium up-regulated ERK1/2 via calmodulin-dependent activation of PI3K. Both myosin light chain kinase and Rho-associated kinase acted as mediators of ERK1/2-dependent migration. Restoring NCX1 expression in β-KD cells reduced migration rate and ERK1/2 activation, suggesting that NCX1 functions downstream of Na,K-β in regulating cell migration. In parallel, inhibition of NCX1 by KB-R7943 in Madin-Darby canine kidney cells, LLC-PK1, and human primary renal epithelial cells (HREpiC) increased ERK1/2 activation and cell migration. This increased migration was associated with high myosin light chain phosphorylation by PI3K/ERK-dependent mechanism in HREpiC cells. These data confirm the role of NCX1 activity in regulating renal epithelial cell migration. PMID:25770213

  3. Inhibition of A/Human/Hubei/3/2005 (H3N2) influenza virus infection by silver nanoparticles in vitro and in vivo

    PubMed Central

    Xiang, Dongxi; Zheng, Yang; Duan, Wei; Li, Xiujing; Yin, Jianjian; Shigdar, Sarah; O’Connor, Michael Liam; Marappan, Manju; Zhao, Xiaojuan; Miao, Yingqiu; Xiang, Bin; Zheng, Conglong

    2013-01-01

    Silver nanoparticles (AgNPs) have attracted much attention as antimicrobial agents and have demonstrated efficient inhibitory activity against various viruses, including human immunodeficiency virus, hepatitis B virus, and Tacaribe virus. In this study, we investigated if AgNPs could have antiviral and preventive effects in A/Human/Hubei/3/2005 (H3N2) influenza virus infection. Madin-Darby canine kidney cells infected with AgNP-treated H3N2 influenza virus showed better viability (P<0.05 versus influenza virus control) and no obvious cytopathic effects compared with an influenza virus control group and a group treated with the solvent used for preparation of the AgNPs. Hemagglutination assay indicated that AgNPs could significantly inhibit growth of the influenza virus in Madin-Darby canine kidney cells (P<0.01 versus the influenza virus control). AgNPs significantly reduced cell apoptosis induced by H3N2 influenza virus at three different treatment pathways (P<0.05 versus influenza virus control). H3N2 influenza viruses treated with AgNPs were analyzed by transmission electron microscopy and found to interact with each other, resulting in destruction of morphologic viral structures in a time-dependent manner in a time range of 30 minutes to 2 hours. In addition, intranasal AgNP administration in mice significantly enhanced survival after infection with the H3N2 influenza virus. Mice treated with AgNPs showed lower lung viral titer levels and minor pathologic lesions in lung tissue, and had a marked survival benefit during secondary intranasal passage in vivo. These results provide evidence that AgNPs have beneficial effects in preventing H3N2 influenza virus infection both in vitro and in vivo, and demonstrate that AgNPs can be used as potential therapeutics for inhibiting outbreaks of influenza. PMID:24204140

  4. Molecular cloning and characterization of canine ICOS.

    PubMed

    Lee, Je-Hwan; Joo, Young-Don; Yim, Daesong; Lee, Richard; Ostrander, Elaine A; Loretz, Carol; Little, Marie-Térèse; Storb, Rainer; Kuhr, Christian S

    2004-10-01

    Inducible costimulatory receptor (ICOS) is one recently identified member of the CD28 family of costimulatory molecules. Evidence suggests ICOS functions as a critical immune regulator and, to evaluate these effects, we employed the canine model system that has been used to develop strategies currently in clinical use for hematopoietic stem cell transplantation. To investigate the effects of blocking the ICOS pathway in the canine hematopoietic cell transplantation model, we tested existing murine and human reagents and cloned the full length of the open reading frame of canine ICOS cDNA to allow the development of reagents specific for the canine ICOS. Canine ICOS contains a major open reading frame of 624 nucleotides, encoding a protein of 208 amino acids, and localizes to chromosome 37. Canine ICOS shares 79% sequence identity with human ICOS, 70% with mouse, and 69% with rat. Canine ICOS expression is limited to stimulated PBMC. PMID:15475250

  5. Canine lymphoma: a review.

    PubMed

    Zandvliet, M

    2016-06-01

    Canine lymphoma (cL) is a common type of neoplasia in dogs with an estimated incidence rate of 20-100 cases per 100,000 dogs and is in many respects comparable to non-Hodgkin lymphoma in humans. Although the exact cause is unknown, environmental factors and genetic susceptibility are thought to play an important role. cL is not a single disease, and a wide variation in clinical presentations and histological subtypes is recognized. Despite this potential variation, most dogs present with generalized lymphadenopathy (multicentric form) and intermediate to high-grade lymphoma, more commonly of B-cell origin. The most common paraneoplastic sign is hypercalcemia that is associated with the T-cell immunophenotype. Chemotherapy is the treatment of choice and a doxorubicin-based multidrug protocol is currently the standard of care. A complete remission is obtained for most dogs and lasts for a median period of 7-10 months, resulting in a median survival of 10-14 months. Many prognostic factors have been reported, but stage, immunophenotype, tumor grade, and response to chemotherapy appear of particular importance. Failure to respond to chemotherapy suggests drug resistance, which can be partly attributed to the expression of drug transporters of the ABC-transporter superfamily, including P-gp and BCRP. Ultimately, most lymphomas will become drug resistant and the development of treatments aimed at reversing drug resistance or alternative treatment modalities (e.g. immunotherapy and targeted therapy) are of major importance. This review aims to summarize the relevant data on cL, as well as to provide an update of the recent literature. PMID:26953614

  6. What's eating you? Canine scabies.

    PubMed

    Burroughs, Richard F; Elston, Dirk M

    2003-08-01

    Infestation with Sarcoptes scabiei var canis, the causative strain of canine scabies, can produce a pruritic rash in humans. The rash generally manifests within 24 to 96 hours of contact with the affected pet. Scrapings are generally negative, and the correct diagnosis requires a high index of suspicion. PMID:12953932

  7. 9 CFR 113.305 - Canine Hepatitis and Canine Adenovirus Type 2 Vaccine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... dilution in a varying serum-constant virus neutralization test using 50 to 300 TCID50 of canine adenovirus... virus neutralization test using 50 to 300 TCID50 of canine adenovirus. (i) A geometric mean titer of...

  8. 9 CFR 113.305 - Canine Hepatitis and Canine Adenovirus Type 2 Vaccine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... dilution in a varying serum-constant virus neutralization test using 50 to 300 TCID50 of canine adenovirus... virus neutralization test using 50 to 300 TCID50 of canine adenovirus. (i) A geometric mean titer of...

  9. 9 CFR 113.305 - Canine Hepatitis and Canine Adenovirus Type 2 Vaccine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... dilution in a varying serum-constant virus neutralization test using 50 to 300 TCID50 of canine adenovirus... virus neutralization test using 50 to 300 TCID50 of canine adenovirus. (i) A geometric mean titer of...

  10. Genetics of Human and Canine Dilated Cardiomyopathy

    PubMed Central

    Simpson, Siobhan; Edwards, Jennifer; Ferguson-Mignan, Thomas F. N.; Cobb, Malcolm; Mongan, Nigel P.; Rutland, Catrin S.

    2015-01-01

    Cardiovascular disease is a leading cause of death in both humans and dogs. Dilated cardiomyopathy (DCM) accounts for a large number of these cases, reported to be the third most common form of cardiac disease in humans and the second most common in dogs. In human studies of DCM there are more than 50 genetic loci associated with the disease. Despite canine DCM having similar disease progression to human DCM studies into the genetic basis of canine DCM lag far behind those of human DCM. In this review the aetiology, epidemiology, and clinical characteristics of canine DCM are examined, along with highlighting possible different subtypes of canine DCM and their potential relevance to human DCM. Finally the current position of genetic research into canine and human DCM, including the genetic loci, is identified and the reasons many studies may have failed to find a genetic association with canine DCM are reviewed. PMID:26266250

  11. Canine mammary tumours, an overview.

    PubMed

    Sleeckx, N; de Rooster, H; Veldhuis Kroeze, E J B; Van Ginneken, C; Van Brantegem, L

    2011-12-01

    Canine mammary tumours (CMTs) are the most common neoplasms in intact female dogs. Although the prevalence of these tumours decreases in regions where preventive ovari(ohyster)ectomy is performed, it remains an important disease entity in veterinary medicine. Moreover, treatment options are limited in comparison with human breast cancer. Nevertheless, recent human treatment protocols might have potential in bitches suffering from CMTs. PMID:21645126

  12. Canine adenovirus based rabies vaccines.

    PubMed

    Tordo, N; Foumier, A; Jallet, C; Szelechowski, M; Klonjkowski, B; Eloit, M

    2008-01-01

    Adenovirus based vectors are very attractive candidates for vaccination purposes as they induce in mammalian hosts potent humoral, mucosal and cellular immune responses to antigens encoded by the inserted genes. We have generated E1-deleted and replication-competent recombinant canine type-2 adenoviruses expressing the rabies virus glycoprotein (G). The effectiveness of both vectors to express a native G protein has been characterized in vitro in permissive cell lines. We compared the humoral and cellular immune responses induced in mice by intramuscular injection of the recombinant canine adenovirus vectors with those induced by a human (Ad5) E1-deleted virus expressing the same rabies G protein. Humoral responses specific to the adenoviruses or the rabies glycoprotein antigens were studied. The influence of the mouse strain was observed using replication-competent canine adenovirus. A high level of rabies neutralizing antibody was observed upon i.m. inoculation, and 100% of mice survived lethal challenge. These results are very promising in the perspective of oral vaccine for dog rabies control. PMID:18634509

  13. Genome Sequence of Canine Herpesvirus

    PubMed Central

    Papageorgiou, Konstantinos V.; Suárez, Nicolás M.; Wilkie, Gavin S.; McDonald, Michael; Graham, Elizabeth M.; Davison, Andrew J.

    2016-01-01

    Canine herpesvirus is a widespread alphaherpesvirus that causes a fatal haemorrhagic disease of neonatal puppies. We have used high-throughput methods to determine the genome sequences of three viral strains (0194, V777 and V1154) isolated in the United Kingdom between 1985 and 2000. The sequences are very closely related to each other. The canine herpesvirus genome is estimated to be 125 kbp in size and consists of a unique long sequence (97.5 kbp) and a unique short sequence (7.7 kbp) that are each flanked by terminal and internal inverted repeats (38 bp and 10.0 kbp, respectively). The overall nucleotide composition is 31.6% G+C, which is the lowest among the completely sequenced alphaherpesviruses. The genome contains 76 open reading frames predicted to encode functional proteins, all of which have counterparts in other alphaherpesviruses. The availability of the sequences will facilitate future research on the diagnosis and treatment of canine herpesvirus-associated disease. PMID:27213534

  14. Canine leishmaniosis - an emerging disease.

    PubMed

    Kaszak, Ilona; Planellas, Marta; Dworecka-Kaszak, Bożena

    2015-01-01

    Canine leishmaniosis (CanL) is an invasive disease of dogs, caused by Leishmania spp. parasites transmitted by the bite of an infected phlebotomine sand fly. CanL is declared an important disease by World Organisation for Animal Health (OIE). Due to its zoonotic potential is of a great importance the prevention of this disease in non endemic areas. Canine leishmaniosis is endemic disease in more than 70 countries and is a common disease in Mediterranean region. Recently, many cases have been reported in non endemic areas, like United Kingdom, Germany and Poland as well, where this disease is considered exotic. The aim of this article is to summarize shortly canine leishmaniosis, it's transmission, clinical manifestations, diagnostics procedure, treatment, prognosis and prevention. Increasing knowledge about this disease can be of a great use for veterinary surgeons from countries where CanL is an emerging disease. Multiple clinical presentations of CanL should aware clinicians to include leishmaniosis in the differential diagnosis of most clinical cases. Unfortunately, even if dogs recover clinically after treatment, complete elimination of Leishmania spp. is rarely achieved, and they remain infected and may relapse. PMID:26342500

  15. Protein 4.1-mediated membrane targeting of human discs large in epithelial cells.

    PubMed

    Hanada, Toshihiko; Takeuchi, Atsuko; Sondarva, Gautam; Chishti, Athar H

    2003-09-01

    Human discs large (hDlg) protein binds to protein 4.1R via a motif encoded by an alternatively spliced exon located between the SH3 and the C-terminal guanylate kinase-like domains. To evaluate the functional significance of protein 4.1R binding for subcellular localization of hDlg in vivo, we expressed full-length recombinant constructs of two naturally occurring isoforms of hDlg termed hDlg-I2 and hDlg-I3. The hDlg-I3 but not the hDlg-I2 isoform binds to the FERM (Four.1-Ezrin-Radixin-Moesin) domain of protein 4.1R in vitro. Upon transient transfection into subconfluent Madine-Darby canine kidney (MDCK) epithelial cells, the hDlg-I3 fused with the green fluorescent protein accumulated predominantly at the plasma membrane of cell-cell contact sites, whereas the hDlg-I2 fusion protein distributed in the cytoplasm. In contrast, in stably transfected confluent MDCK cells, both hDlg-I2 and -I3 isoforms localized efficiently to the lateral membrane, consistent with the previous notion that the N-terminal domain of hDlg mediates its membrane targeting in polarized epithelial cells. We introduced a double mutation (I38A/I40A) into the N-terminal domain of hDlg, which disrupted its interaction with DLG2, a key event in the membrane targeting of hDlg. Interestingly, the hDlg-I2 isoform harboring the I38A/I40A mutation mislocalized from the membrane into cytoplasm. Importantly, the hDlg-I3 isoform with the same mutation localized efficiently to the membrane of confluent MDCK cells. Together, our results demonstrate that in addition to the N-terminal targeting domain, the alternatively spliced I3 insertion plays a critical role in recruiting hDlg to the lateral membrane in epithelial cells via its interaction with protein 4.1R. PMID:12807908

  16. Coupling of epithelial Na+ and Cl− channels by direct and indirect activation by serine proteases

    PubMed Central

    Gondzik, Veronika; Weber, Wolf Michael

    2012-01-01

    The mammalian collecting duct (CD) is continuously exposed to urinary proteases. The CD expresses an epithelial Na+ channel (ENaC) that is activated after cleavage by serine proteases. ENaC also exists at the plasma membrane in the uncleaved form, rendering activation by extracellular proteases an important mechanism for regulating Na+ transport. Many exogenous and a small number of endogenous extracellular serine proteases have been shown to activate the channel. Recently, kallikrein 1 (KLK1) was shown to increase γENaC cleavage in the native CD indicating a possible direct role of this endogenous protease in Na+ homeostasis. To explore this process, we examined the coordinated effect of this protease on Na+ and Cl− transport in a polarized renal epithelial cell line (Madin-Darby canine kidney). We also examined the role of native urinary proteases in this process. Short-circuit current (Isc) was used to measure transport of these ions. The Isc exhibited an ENaC-dependent Na+ component that was amiloride blockable and a cystic fibrosis transmembrane conductance regulator (CFTR)-dependent Cl− component that was blocked by inhibitor 172. Apical application of trypsin, an exogenous S1 serine protease, activated IENaC but was without effects on ICFTR. Subtilisin an exogenous S8 protease that mimics endogenous furin-type proteases activated both currents. A similar activation was also observed with KLK1 and native rat urinary proteases. Activation with urinary proteases occurred within minutes and at protease concentrations similar to those in the CD indicating physiological significance of this process. ENaC activation was irreversible and mediated by enhanced cleavage of γENaC. The activation of CFTR was indirect and likely dependent on activation of an endogenous apical membrane protease receptor. Collectively, these data demonstrate coordinated stimulation of separate Na+ and Cl− transport pathways in renal epithelia by extracellular luminal proteases. They

  17. Functional expression and apical localization of the cystic fibrosis transmembrane conductance regulator in MDCK I cells.

    PubMed

    Mohamed, A; Ferguson, D; Seibert, F S; Cai, H M; Kartner, N; Grinstein, S; Riordan, J R; Lukacs, G L

    1997-02-15

    The gene product affected in cystic fibrosis, the cystic fibrosis transmembrane conductance regulator (CFTR), is a chlorideselective ion channel that is regulated by cAMP-dependent protein kinase-mediated phosphorylation, ATP binding and ATP hydrolysis. Mutations in the CFTR gene may result in cystic fibrosis characterized by severe pathology (e.g. recurrent pulmonary infection, male infertility and pancreatic insufficiency) involving organs expressing the CFTR. Interestingly, in the kidney, where expression of the CFTR has been reported, impaired ion transport in patients suffering from cystic fibrosis could not be observed. To understand the role of the CFTR in chloride transport in the kidney, we attempted to identify an epithelial cell line that can serve as a model. We demonstrate that the CFTR is expressed constitutively in Madine-Darby canine kidney (MDCK) type I cells, which are thought to have originated from the distal tubule of the dog nephron. We show expression at the mRNA level, using reverse transcriptase-PCR, and at the protein level, using Western blot analysis with three different monoclonal antibodies. Iodide efflux measurements indicate that CFTR expression confers a plasma membrane anion conductance that is responsive to stimulation by cAMP. The cAMP-stimulated iodide release is sensitive to glybenclamide, diphenylamine carboxylic acid and 5-nitro-2-(3-phenylpropylamino)benzoic acid, but not to 4,4'-di-isothiocyanostilbene-2,2'-disulphonic acid, an inhibitor profile characteristic of the CFTR chloride channel. Finally, the polarized localization of the CFTR to the apical plasma membrane was established by iodide efflux measurements and cell-surface biotinylation on MDCK I monolayers. Interestingly, MDCK type II cells, which are thought to have originated from the proximal tubule of the kidney, lack CFTR protein expression and cAMP-stimulated chloride conductance. In conclusion, we propose that MDCK type I and II cells can serve as convenient

  18. Functional expression and apical localization of the cystic fibrosis transmembrane conductance regulator in MDCK I cells.

    PubMed Central

    Mohamed, A; Ferguson, D; Seibert, F S; Cai, H M; Kartner, N; Grinstein, S; Riordan, J R; Lukacs, G L

    1997-01-01

    The gene product affected in cystic fibrosis, the cystic fibrosis transmembrane conductance regulator (CFTR), is a chlorideselective ion channel that is regulated by cAMP-dependent protein kinase-mediated phosphorylation, ATP binding and ATP hydrolysis. Mutations in the CFTR gene may result in cystic fibrosis characterized by severe pathology (e.g. recurrent pulmonary infection, male infertility and pancreatic insufficiency) involving organs expressing the CFTR. Interestingly, in the kidney, where expression of the CFTR has been reported, impaired ion transport in patients suffering from cystic fibrosis could not be observed. To understand the role of the CFTR in chloride transport in the kidney, we attempted to identify an epithelial cell line that can serve as a model. We demonstrate that the CFTR is expressed constitutively in Madine-Darby canine kidney (MDCK) type I cells, which are thought to have originated from the distal tubule of the dog nephron. We show expression at the mRNA level, using reverse transcriptase-PCR, and at the protein level, using Western blot analysis with three different monoclonal antibodies. Iodide efflux measurements indicate that CFTR expression confers a plasma membrane anion conductance that is responsive to stimulation by cAMP. The cAMP-stimulated iodide release is sensitive to glybenclamide, diphenylamine carboxylic acid and 5-nitro-2-(3-phenylpropylamino)benzoic acid, but not to 4,4'-di-isothiocyanostilbene-2,2'-disulphonic acid, an inhibitor profile characteristic of the CFTR chloride channel. Finally, the polarized localization of the CFTR to the apical plasma membrane was established by iodide efflux measurements and cell-surface biotinylation on MDCK I monolayers. Interestingly, MDCK type II cells, which are thought to have originated from the proximal tubule of the kidney, lack CFTR protein expression and cAMP-stimulated chloride conductance. In conclusion, we propose that MDCK type I and II cells can serve as convenient

  19. Bilateral Mandibular Supernumerary Canines: A Case Report

    PubMed Central

    Abouei Mehrizi, Ehsan; Semyari, Hassan; Eslami Amirabadi, Gholamreza

    2010-01-01

    Supernumerary teeth are defined as the teeth developed in excess of the number found in a normal dentition. Supernumerary canine is an extremely rare finding particularly in the mandible. This case report presents a 25-year-old female patient with the unique feature of bilateral mandibular supplemental supernumerary canines. The patient was non-syndromic without any other supernumerary teeth. PMID:23346342

  20. Canine and feline parasitic zoonoses in China

    PubMed Central

    2012-01-01

    Canine and feline parasitic zoonoses have not been given high priority in China, although the role of companion animals as reservoirs for zoonotic parasitic diseases has been recognized worldwide. With an increasing number of dogs and cats under unregulated conditions in China, the canine and feline parasitic zoonoses are showing a trend towards being gradually uncontrolled. Currently, canine and feline parasitic zoonoses threaten human health, and cause death and serious diseases in China. This article comprehensively reviews the current status of major canine and feline parasitic zoonoses in mainland China, discusses the risks dogs and cats pose with regard to zoonotic transmission of canine and feline parasites, and proposes control strategies and measures. PMID:22839365

  1. Concomitant canine distemper, infectious canine hepatitis, canine parvoviral enteritis, canine infectious tracheobronchitis, and toxoplasmosis in a puppy.

    PubMed

    Headley, Selwyn Arlington; Alfieri, Amauri Alcindo; Fritzen, Juliana Torres Tomazi; Garcia, João Luis; Weissenböck, Herbert; da Silva, Ana Paula; Bodnar, Livia; Okano, Werner; Alfieri, Alice Fernandes

    2013-01-01

    The concomitant infections of Canine distemper virus (CDV), Canine adenovirus A types 1 (CAdV-1) and 2 (CAdV-2), Canine parvovirus type 2 (CPV-2), and Toxoplasma gondii are described in a 43-day-old mixed-breed puppy. Clinically, there were convulsions and blindness with spontaneous death; 14 siblings of this puppy, born to a 10-month-old dam, which was seropositive (titer: 1,024) for T. gondii, also died. Necropsy revealed unilateral corneal edema (blue eye), depletion of intestinal lymphoid tissue, non-collapsible lungs, congestion of meningeal vessels, and a pale area in the myocardium. Histopathology demonstrated necrotizing myocarditis associated with intralesional apicomplexan protozoa; necrotizing and chronic hepatitis associated with rare intranuclear inclusion bodies within hepatocytes; necrotizing bronchitis and bronchiolitis; interstitial pneumonia associated with eosinophilic intracytoplasmic inclusion bodies within epithelial cells; atrophy and fusion of intestinal villi with cryptal necrosis; and white matter demyelination of the cerebrum and cerebellum associated with intranuclear inclusion bodies within astrocytes. Polymerase chain reaction (PCR) amplified the partial fragments (bp) of the CDV N gene (290 bp), CPV-2c VP2 capsid protein gene (583 bp), and CAdV-1 (508 bp) and CAdV-2 (1,030 bp) E gene from urine and tissue samples. The PCR assays demonstrated that the apicomplexan protozoa observed within several organs contained DNA specific for T. gondii; genotyping revealed T. gondii type III. The findings support the characterization of concomitant infections of CDV, CAdV-1, CAdV-2, CPV-2, and T. gondii in this puppy. Further, seroreactivity to T. gondii of the dam in association with the systemic disease observed in the puppy described herein is suggestive of congenital toxoplasmosis. PMID:23293164

  2. Canine procalcitonin messenger RNA expression.

    PubMed

    Kuzi, Sharon; Aroch, Itamar; Peleg, Keren; Karnieli, Ohad; Klement, Eyal; Dank, Gillian

    2008-09-01

    Procalcitonin is considered an acute phase protein used as both a marker of infection and prognosis in human medicine. Canine procalcitonin has been previously sequenced; however, its use as a diagnostic or prognostic tool in dogs has never been assessed. A quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay for canine procalcitonin messenger RNA (mRNA) was developed. Whole blood samples were collected from ill and healthy dogs. RNA was extracted and the real-time PCR was assessed. The patients' diagnoses, complete blood cell count, and differential leukocyte count results were recorded. Based on the diagnosis, dogs were divided into 5 groups: inflammatory, infectious, neoplastic, other diseases, and healthy controls. Procalcitonin mRNA expression and the hematological measures were compared between groups, and their correlations were assessed. Procalcitonin mRNA expression was assessed in 70 dogs, including infectious (17), noninfectious inflammatory (17), neoplastic (18), other diseases (7), and healthy controls (11), and was significantly (P < 0.001) higher in all ill dogs versus controls. Procalcitonin may therefore be considered an acutephase protein in dogs. However, there were no significant differences in procalcitonin mRNA expression between ill dog groups and no correlations between its expression levels and hematological measures. In 5 dogs of all disease categories, procalcitonin mRNA expression was measured twice during the course of disease. The changes in its levels were in agreement with the clinical evaluation of improvement or deterioration, suggesting a possible prognostic value. PMID:18776098

  3. Neuroinflammation in advanced canine glaucoma

    PubMed Central

    Jiang, Bing; Harper, Matthew M.; Kecova, Helga; Adamus, Grazyna; Kardon, Randy H.; Grozdanic, Sinisa D.

    2010-01-01

    Purpose The pathophysiological events that occur in advanced glaucoma are not well characterized. The principal purpose of this study is to characterize the gene expression changes that occur in advanced glaucoma. Methods Retinal RNA was obtained from canine eyes with advanced glaucoma as well as from healthy eyes. Global gene expression patterns were determined using oligonucleotide microarrays and confirmed by real-time PCR. The presence of tumor necrosis factor (TNF) and its receptors was evaluated by immunolabeling. Finally, we evaluated the presence of serum autoantibodies directed against retinal epitopes using western blot analyses. Results We identified over 500 genes with statistically significant changes in expression level in the glaucomatous retina. Decreased expression levels were detected for large number of functional groups, including synapse and synaptic transmission, cell adhesion, and calcium metabolism. Many of the molecules with decreased expression levels have been previously shown to be components of retinal ganglion cells. Genes with elevated expression in glaucoma are largely associated with inflammation, such as antigen presentation, protein degradation, and innate immunity. In contrast, expression of many other pro-inflammatory genes, such as interferons or interleukins, was not detected at abnormal levels. Conclusions This study characterizes the molecular events that occur in the canine retina with advanced glaucoma. Our data suggest that in the dog this stage of the disease is accompanied by pronounced retinal neuroinflammation. PMID:21042562

  4. Evidence for canine rehabilitation and physical therapy.

    PubMed

    Millis, Darryl L; Ciuperca, Ionut Alexandru

    2015-01-01

    This article reviews some important studies regarding canine physical rehabilitation. Bones, cartilage, muscles, ligaments, and tendons undergo atrophy if loading is decreased. Knowledge of the changes that occur with immobilization and the time course of events helps in the development of a rehabilitation program to improve tissue integrity. Outcome assessment instruments are clinically useful indicators of patient progress and the success of rehabilitation programs. A number of physical modalities are used in canine rehabilitation, although there are relatively few canine-specific studies. Rehabilitation has specific benefits in the treatment of various orthopedic and neurologic conditions. PMID:25432679

  5. Comparative functional characterization of canine IgG subclasses.

    PubMed

    Bergeron, Lisa M; McCandless, Erin E; Dunham, Steve; Dunkle, Bill; Zhu, Yaqi; Shelly, John; Lightle, Sandra; Gonzales, Andrea; Bainbridge, Graeme

    2014-01-15

    To date, very little is known about the functional characteristics of the four published canine IgG subclasses. It is not clear how each subclass engages the immune system via complement-dependent cytotoxicity (CDC) or antibody-dependent cell-mediated cytotoxicity (ADCC), or how long each antibody may last in serum. Such information is critical for understanding canine immunology and for the discovery of canine therapeutic monoclonal antibodies. Through both in vitro and ex vivo experiments to evaluate canine Fc's for effector function, complement binding, FcRn binding, and ADCC, we are now able to categorize canine subclasses by function. The subclasses share functional properties with the four human IgG subclasses and are reported herein with their function-based human analog. Canine Fc fusions, canine chimeras, and caninized antibodies were characterized. Canine subclasses A and D appear effector-function negative while subclasses B and C bind canine Fc gamma receptors and are positive for ADCC. All canine subclasses bind the neonatal Fc receptor except subclass C. By understanding canine IgGs in this way, we can apply what is known of human immunology toward translational and veterinary medicine. Thus, this body of work lays the foundation for evaluating canine IgG subclasses for therapeutic antibody development and builds upon the fundamental scholarship of canine immunology. PMID:24268690

  6. Estimating canine tooth crown height in early Australopithecus.

    PubMed

    Plavcan, J Michael; Ward, Carol V; Paulus, Faydre L

    2009-07-01

    Canine tooth size reduction and the associated reduction in canine dimorphism is a basal hominin character that also provides important evidence for models of behavioral evolution. Two specimens of Australopithecus anamensis (KNM-KP 29287 and KNM-KP 29283) that do not preserve the canine crown, but do preserve the root or alveolus, appear to suggest that canine size variation and canine dimorphism in this species may have been greater than in other hominins. We evaluate canine root and crown dimensions in a series of extant hominoids, and estimate canine crown height in Australopithecus afarensis and A. anamensis. Our results demonstrate that it is possible to generate estimates of canine crown height from basal canine crown and root dimensions with a moderate degree of accuracy. Estimates of maxillary canine crown size for A. anamensis are slightly larger than those of A. afarensis, and are approximately the same size as canines of modern female chimpanzees. Estimated mandibular canine crown height is very similar in the two species. Variation within the A. anamensis sample of estimated canine crown heights is similar to that of modern humans, suggesting a low degree of sexual dimorphism. Inclusion of estimates for KNM-KP 29287 and KNM-KP 29283 does not substantially increase either the estimate of overall canine size or variation for A. anamensis. PMID:19482334

  7. The role of pro- and anti-inflammatory cytokines in the pathogenesis of spontaneous canine CNS diseases.

    PubMed

    Spitzbarth, I; Baumgärtner, W; Beineke, A

    2012-06-15

    Dogs are comparatively frequently affected by various spontaneously occurring inflammatory and degenerative central nervous system (CNS) conditions, and immunopathological processes are a hallmark of the associated neuropathology. Due to the low regenerative capacity of the CNS a sophisticated understanding of the underlying molecular basis for disease initiation, progression and remission in canine CNS diseases represents a prerequisite for the development of novel therapeutical approaches. In addition, as many spontaneous canine CNS diseases share striking similarities with their human counterpart, knowledge about the immune pathogenesis may in part be translated for a better understanding of certain human diseases. In addition to cytokine-driven differentiation of peripheral leukocytes including different subsets of T cells recent research suggests a pivotal role of these mediators also in phenotype polarization of resident glial cells. Cytokines thus represent the key mediators of the local and systemic immune response in CNS diseases and their orchestration significantly decides on either lesion progression or remission. The aim of the present review is to summarize the growing number of data focusing on the molecular basis of the immune response during spontaneous canine CNS diseases and to detail the effect of cytokines on the immune pathogenesis of selected idiopathic, infectious, and traumatic canine CNS diseases. Steroid-responsive meningitis arteritis (SRMA) represents a unique idiopathic disease of leptomeningeal blood vessels characterized by excessive IgA secretion into the cerebrospinal fluid. Recent reports have given sophisticated insights into the cytokine-driven, immune-mediated pathogenesis of SRMA that is characterized by a biased T helper 2 cell response. Canine distemper associated leukoencephalitis represents an important spontaneously occurring disease that allows investigations on the basic pathogenesis of immune-mediated myelin loss. It

  8. Etiology of maxillary canine impaction: a review.

    PubMed

    Becker, Adrian; Chaushu, Stella

    2015-10-01

    This article is a review that enumerates the causes of impaction of the maxillary permanent canines, including hard tissue obstructions, soft tissue lesions, and anomalies of neighboring teeth, and discusses the much-argued relationship between environmental and genetic factors. These phenomena have been shown in many investigations to accompany the diagnosis of canine impaction and have been presented as unrelated anomalous features, each of which is etiologically construed as genetic, including the aberrant canine itself. While in general the influence of genetics pervades the wider picture, a guidance theory proposes an alternative etiologic line of reasoning and interpretation of these studies, in which the same genetically determined anomalous features provide an abnormal milieu in which the canine is reared and from which it is guided in its misdirected and often abortive path of eruption. PMID:26432311

  9. Canine adenovirus type 1 in a fennec fox (Vulpes zerda).

    PubMed

    Choi, Jeong-Won; Lee, Hyun-Kyoung; Kim, Seong-Hee; Kim, Yeon-Hee; Lee, Kyoung-Ki; Lee, Myoung-Heon; Oem, Jae-Ku

    2014-12-01

    A 10-mo-old female fennec fox (Vulpes zerda) with drooling suddenly died and was examined postmortem. Histologic examination of different tissue samples was performed. Vacuolar degeneration and diffuse fatty change were observed in the liver. Several diagnostic methods were used to screen for canine parvovirus, canine distemper virus, canine influenza virus, canine coronavirus, canine parainfluenza virus, and canine adenovirus (CAdV). Only CAdV type 1 (CAdV-1) was detected in several organs (liver, lung, brain, kidney, spleen, and heart), and other viruses were not found. CAdV-1 was confirmed by virus isolation and nucleotide sequencing. PMID:25632689

  10. [Nonsurgical endodontic treatment of an invaginated canine].

    PubMed

    Fernández Guerrero, F; Miñana Laliga, R; Bullon Fernandez, P

    1989-01-01

    We present a case of a maxillary canine with a dens invaginatus treated successfully. The patient had pain, swelling and a sinus tract coming from the inmature apex of the canine. The canals were enlarged and cleaned and the main canal was filled with Calcium Hydroxide to allow the root development. Seven months later, the patient was asymptomatic and the tooth was obturated with guttapercha. One year later it was confirm the success in the treatment. PMID:2638021

  11. Rootless eruption of a mandibular permanent canine.

    PubMed

    Shapira, Yehoshua; Kuftinec, Mladen M

    2011-04-01

    The purpose of this article was to describe the rootless eruption of a mandibular permanent canine in a 10-year-old boy; his mandible had been fractured in a car accident. The fracture was at the region of the developing canine, resulting in arrested root formation and causing abnormal, rootless eruption. Current theories on tooth eruption and the important role of the dental follicle in the process of eruption are discussed. PMID:21457868

  12. Canine Cytogenetics - From band to basepair

    PubMed Central

    Breen, Matthew

    2008-01-01

    Humans and dogs have coexisted for thousands of years, during which time we have developed a unique bond, centered on companionship. Along the way, we have developed purebred dog breeds in a manner that has resulted unfortunately in many of them being affected by serious genetic disorders, including cancers. With serendipity and irony the unique genetic architecture of the 21st Century genome of Man's best friend may ultimately provide many of the keys to unlock some of nature's most intriguing biological puzzles. Canine cytogenetics has advanced significantly over the past 10 years, spurred on largely by the surge of interest in the dog as a biomedical model for genetic disease and the availability of advanced genomics resources. As such the role of canine cytogenetics has moved rapidly from one that served initially to define the gross genomic organization of the canine genome and provide a reliable means to determine the chromosomal location of individual genes, to one that enabled the assembled sequence of the canine genome to be anchored to the karyotype. Canine cytogenetics now presents the biomedical research community with a means to assist in our search for a greater understanding of how genome architectures altered during speciation and in our search for genes associated with cancers that affect both dogs and humans. The cytogenetics ‘toolbox’ for the dog is now loaded. This review aims to provide a summary of some of the recent advancements in canine cytogenetics. PMID:18467825

  13. Environmental contamination by canine geohelminths

    PubMed Central

    2014-01-01

    Intestinal nematodes affecting dogs, i.e. roundworms, hookworms and whipworms, have a relevant health-risk impact for animals and, for most of them, for human beings. Both dogs and humans are typically infected by ingesting infective stages, (i.e. larvated eggs or larvae) present in the environment. The existence of a high rate of soil and grass contamination with infective parasitic elements has been demonstrated worldwide in leisure, recreational, public and urban areas, i.e. parks, green areas, bicycle paths, city squares, playgrounds, sandpits, beaches. This review discusses the epidemiological and sanitary importance of faecal pollution with canine intestinal parasites in urban environments and the integrated approaches useful to minimize the risk of infection in different settings. PMID:24524656

  14. Environmental contamination by canine geohelminths.

    PubMed

    Traversa, Donato; Frangipane di Regalbono, Antonio; Di Cesare, Angela; La Torre, Francesco; Drake, Jason; Pietrobelli, Mario

    2014-01-01

    Intestinal nematodes affecting dogs, i.e. roundworms, hookworms and whipworms, have a relevant health-risk impact for animals and, for most of them, for human beings. Both dogs and humans are typically infected by ingesting infective stages, (i.e. larvated eggs or larvae) present in the environment. The existence of a high rate of soil and grass contamination with infective parasitic elements has been demonstrated worldwide in leisure, recreational, public and urban areas, i.e. parks, green areas, bicycle paths, city squares, playgrounds, sandpits, beaches. This review discusses the epidemiological and sanitary importance of faecal pollution with canine intestinal parasites in urban environments and the integrated approaches useful to minimize the risk of infection in different settings. PMID:24524656

  15. Age estimation from canine volumes.

    PubMed

    De Angelis, Danilo; Gaudio, Daniel; Guercini, Nicola; Cipriani, Filippo; Gibelli, Daniele; Caputi, Sergio; Cattaneo, Cristina

    2015-08-01

    Techniques for estimation of biological age are constantly evolving and are finding daily application in the forensic radiology field in cases concerning the estimation of the chronological age of a corpse in order to reconstruct the biological profile, or of a living subject, for example in cases of immigration of people without identity papers from a civil registry. The deposition of teeth secondary dentine and consequent decrease of pulp chamber in size are well known as aging phenomena, and they have been applied to the forensic context by the development of age estimation procedures, such as Kvaal-Solheim and Cameriere methods. The present study takes into consideration canines pulp chamber volume related to the entire teeth volume, with the aim of proposing new regression formulae for age estimation using 91 cone beam computerized scans and a freeware open-source software, in order to permit affordable reproducibility of volumes calculation. PMID:25698302

  16. CANINE: a robotic mine dog

    NASA Astrophysics Data System (ADS)

    Stancil, Brian A.; Hyams, Jeffrey; Shelley, Jordan; Babu, Kartik; Badino, Hernán.; Bansal, Aayush; Huber, Daniel; Batavia, Parag

    2013-01-01

    Neya Systems, LLC competed in the CANINE program sponsored by the U.S. Army Tank Automotive Research Development and Engineering Center (TARDEC) which culminated in a competition held at Fort Benning as part of the 2012 Robotics Rodeo. As part of this program, we developed a robot with the capability to learn and recognize the appearance of target objects, conduct an area search amid distractor objects and obstacles, and relocate the target object in the same way that Mine dogs and Sentry dogs are used within military contexts for exploration and threat detection. Neya teamed with the Robotics Institute at Carnegie Mellon University to develop vision-based solutions for probabilistic target learning and recognition. In addition, we used a Mission Planning and Management System (MPMS) to orchestrate complex search and retrieval tasks using a general set of modular autonomous services relating to robot mobility, perception and grasping.

  17. 9 CFR 113.202 - Canine Hepatitis and Canine Adenovirus Type 2 Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... serum-constant virus neutralization test using 50 to 300 TCID50 of canine adenovirus. (i) The 20 dogs to... negative at a 1:2 final serum dilution in a varying serum-constant virus neutralization test using 50 to.... (2) Potency test for canine hepatitis—serum neutralization test. Bulk or final container samples...

  18. Effects of vaccines on the canine immune system.

    PubMed Central

    Phillips, T R; Jensen, J L; Rubino, M J; Yang, W C; Schultz, R D

    1989-01-01

    The effects of several commercially available polyvalent canine vaccines on the immune system of the dog were examined. The results demonstrated that the polyvalent vaccines used in this study significantly suppressed the absolute lymphocyte count and that most of the polyvalent vaccines significantly suppressed lymphocyte response to mitogen, but had no effect on natural effector cell activity, neutrophil chemiluminescence, nor antibody response to canine distemper virus. The individual vaccine components from the polyvalent vaccines when inoculated alone did not significantly suppress the lymphocyte response to mitogen. However, when canine distemper virus was combined with canine adenovirus type 1 or canine adenovirus type 2, significant suppression in lymphocyte responsiveness to mitogen occurred. The results indicate that interactions between canine distemper virus and canine adenovirus type 1 or canine adenovirus type 2 are responsible for the polyvalent vaccine induced suppression of lymphocyte responsiveness. PMID:2540897

  19. Transmigration of mandibular canine – case report

    PubMed Central

    Gruszka, Katarzyna; Różyło, T. Katarzyna; Różyło-Kalinowska, Ingrid; Denkiewicz, Katarzyna; Masłowska, Klaudia

    2014-01-01

    Summary Background Transmigration is a phenomenon of movement of an unerupted tooth in the bone across the midline. This anomaly is not often found. Transmigration is more prevalent in females than in males, and more often encountered in the mandible than maxilla, it affects mostly canines. Case Report The aim of this study was to present a case report of a mandibular canine transmigration in a patient aged 12. Intraoral examination determined hypodontia of right second premolar and delayed eruption of left second premolar in maxilla, as well as persistent deciduous teeth: right second molar, left canine and second molar. The patient was referred for a Cone-Beam CT examination, which allowed precise visualization of the transmigrating canine as well as ruled out resorption of roots of mandibular incisors. Results The treatment with a maxillary fixed orthodontic appliance was finished after obtaining a satisfactory result. Proper alignment of the incisors in the anterior-posterior plane and correct midline position were accepted by the patient. Transmigrating canine after consultation with the surgeon was designed to further radiological observation. PMID:24520309

  20. Canine kobuvirus infections in Korean dogs.

    PubMed

    Oem, Jae-Ku; Choi, Jeong-Won; Lee, Myoung-Heon; Lee, Kyoung-Ki; Choi, Kyoung-Seong

    2014-10-01

    To investigate canine kobuvirus (CaKoV) infection, fecal samples (n = 59) were collected from dogs with or without diarrhea (n = 21 and 38, respectively) in the Republic of Korea (ROK) in 2012. CaKoV infection was detected in four diarrheic samples (19.0 %) and five non-diarrheic samples (13.2 %). All CaKoV-positive dogs with diarrhea were found to be infected in mixed infections with canine distemper virus and canine parvovirus or canine adenovirus. There was no significant difference in the prevalence of CaKoV in dogs with and without diarrhea. By phylogenetic analysis based on partial 3D genes and complete genome sequences, the Korean isolates were found to be closely related to each other regardless of whether they were associated with diarrhea, and to the canine kobuviruses identified in the USA and UK. This study supports the conclusion that CaKoVs from different countries are not restricted geographically and belong to a single lineage. PMID:24906525

  1. Immunologic Observations in Canine Interstitial Nephritis

    PubMed Central

    Krohn, Kai; Mero, Matti; Oksanen, Aili; Sandholm, Markus

    1971-01-01

    Immunofluorescence studies in cases of chronic interstitial nephritis (CIN) in the dog demonstrated deposition of canine IgC and C'3 in the thickened capillary walls of the glomeruli and in the mesangium. Eluates obtained from the nephritic kidneys contained antibodies of IgG type and reacted with autologous or homologous nephritic kidneys but not with normal kidneys or with any normal canine tissue. The staining pattern of fluorescein-conjugated eluates was similar to that obtained with anti-canine IgG or anti-canine C'3. The eluates did not contain leptospiral antibodies. The findings indicate that complement-fixing immune complexes are deposited in the damaged glomeruli in CIN. The nature of the antigen involved in these complexes is unknown, but it does not seem to be a component of normal canine tissue and could thus be viral or bacterial. ImagesFig 5Fig 6Fig 7Fig 8Fig 13Fig 14Fig 15Fig 16Fig 9Fig 10Fig 11Fig 12Fig 1Fig 2Fig 3Fig 4 PMID:4106382

  2. Canine rabies ecology in southern Africa.

    PubMed

    Bingham, John

    2005-09-01

    Rabies is a widespread disease in African domestic dogs and certain wild canine populations. Canine rabies became established in Africa during the 20th century, coinciding with ecologic changes that favored its emergence in canids. I present a conceptual and terminologic framework for understanding rabies ecology in African canids. The framework is underpinned by 2 distinct concepts: maintenance and persistence. Maintenance encompasses the notion of indefinite transmission of infection within a local population and depends on an average transmission ratio > or =1. Maintenance in all local populations is inherently unstable, and the disease frequently becomes extinct. Persistence, the notion of long-term continuity, depends on the presence of rabies in > or =1 local population within the canine metapopulation at any time. The implications for understanding rabies ecology and control are reviewed, as are previous studies on rabies ecology in African canids. PMID:16229759

  3. Furcation lesion in a mandibular canine.

    PubMed

    Fonseca, Dimitri Ribas; Sena, Larryson Goncalves; Santos, Maria Helena; Goncalves, Patricia Furtado

    2011-01-01

    Morphological changes can complicate dental treatment. This report presents a rare case of a furcation lesion in a mandibular canine with two roots. A 39-year-old man in general good health sought dental care for severe pain in his maxillary anterior teeth. The clinical examination showed localized swelling in the vestibular mucosa close to the mandibular left canine. Radiographic examination revealed two distinct roots and vertical bone resorption in the canine's mesial surface. Periodontal evaluation led to a diagnosis of periodontal abscess associated with furcation lesion. Despite the occurrence in an atypical location, the site of periodontal furcation received conventional therapy for initial decontamination, including tissue debridement and a combination of polyvinylpyrrolidone irrigation and antibiotics. To improve access, the decontamination was completed with surgical techniques and scaling and root planing. Early diagnosis of this rare morphological change helped to determine appropriate, timely treatment planning and optimal patient recovery. PMID:21903558

  4. Canine neuroendocrine carcinoma. A tumor resembling histiocytoma.

    PubMed

    Nickoloff, B J; Hill, J; Weiss, L M

    1985-12-01

    The clinical and light- and electron microscopic features of 20 cases of canine neuroendocrine carcinoma, initially classified as atypical histiocytomas, are reported. The locally expansile well-circumscribed dermal tumor nodules were composed of solid masses of cells with high mitotic index and multinucleation, arranged in a trabecular pattern with prominent fibrovascular connective tissue stroma rich in reticulin fibers that outlined compact cell nests. Ultrastructural studies revealed evenly dispersed chromatin, focally indented nuclei and abundant cytoplasm with perinuclear filaments, membrane-bound dense core granules, and prominent interdigitating plasma membrane projections with primitive intercellular junctions. Clinical and pathological comparisons between canine neuroendocrine carcinoma, canine histiocytomas, and human Merkel cell neoplasms are discussed. PMID:4091229

  5. The orthodontic management of ectopic canine

    PubMed Central

    Thirunavukkarasu, R.; Sriram, G.; Satish, R.

    2015-01-01

    The canines being the cornerstone of the arch and smile is one of the teeth, which has the longest eruption passage that gets influenced by local and general etiological factors easily. The initial calcification of the crowns starts at 4–5 months of age and proceeds toward eruption about 11–13 years of age with mesiobuccal crown angulation that gets corrected toward occlusion. It gets displaced buccally or palatally or may sometimes get impacted. Early intervention is the best suited to manage canine eruption patterns. Once erupted ectopically, they possess a great challenge in repositioning them back into their correct position. This case report discusses an orthodontic treatment planning and execution to correct a buccally placed canine with an anterior crossbite in an adult. PMID:26538959

  6. A Study of Transmigrated Canine in an Indian Population

    PubMed Central

    Sharma, Gaurav; Nagpal, Archna

    2014-01-01

    Aim. The purpose of this study was to investigate the prevalence of transmigrated canines in a north Indian population and association with gender, side, associated pathologies, and dental anomalies. Subjects and methods. The prospective study consisted of panoramic radiographs of 3000 patients from two dental colleges in north India. The panoramic radiographs were screened for radiographically identified position of the transmigrated tooth, retained canine, and other coexisting dental anomalies. Results. The overall prevalence of transmigrated canines (15 mandibular and 5 maxillary) was 0.66%. The prevalence of mandibular transmigrated canine was 0.5% and maxillary transmigrated canine was 0.16%. All the transmigrated canines were unilateral. The age range was 15–53 years (average age 24.1 years) and there were 12 males (60%) and 8 females (40%). Type 1 mandibular canine transmigration was the commonest type found in our study (10 cases), followed by types 2 and 4 (2 cases each) and 1 case of type 5 transmigration. Conclusion. The prevalence of transmigrated canines in the north Indian population was 0.66% and no gender predilection was evident. The transmigrated canines have a low complication rate (10.0%) and no correlation with other dental anomalies was found. Type 3 canine is the rarest form of mandibular canine transmigration.

  7. Canine Mammary Mixed Tumours: A Review

    PubMed Central

    Dantas Cassali, Geovanni; Cavalheiro Bertagnolli, Angélica; Ferreira, Enio; Araújo Damasceno, Karine; de Oliveira Gamba, Conrado; Bonolo de Campos, Cecília

    2012-01-01

    Mammary mixed tumours are the most frequent neoplasias in female dogs. In humans, mixed tumours are frequently found in the salivary glands and are known as pleomorphic adenomas. In addition to their histomorphologic similarities, mixed tumours and pleomorphic adenomas have the potential to become malignant and give rise to carcinomas in mixed tumours and carcinomas ex-pleomorphic adenoma, respectively. The factors associated with malignant transformation are still poorly known in the case of canine mixed tumours. However, this form of neoplasia tends to be associated with a better prognosis than other malignant histological types. This paper discusses the main features associated with female canine mammary mixed tumours. PMID:23193497

  8. Oncolytic Virotherapy of Canine and Feline Cancer

    PubMed Central

    Gentschev, Ivaylo; Patil, Sandeep S.; Petrov, Ivan; Cappello, Joseph; Adelfinger, Marion; Szalay, Aladar A.

    2014-01-01

    Cancer is the leading cause of disease-related death in companion animals such as dogs and cats. Despite recent progress in the diagnosis and treatment of advanced canine and feline cancer, overall patient treatment outcome has not been substantially improved. Virotherapy using oncolytic viruses is one promising new strategy for cancer therapy. Oncolytic viruses (OVs) preferentially infect and lyse cancer cells, without causing excessive damage to surrounding healthy tissue, and initiate tumor-specific immunity. The current review describes the use of different oncolytic viruses for cancer therapy and their application to canine and feline cancer. PMID:24841386

  9. A report of canine tooth syndrome.

    PubMed

    Lee, William B; O'Halloran, Henry S

    2004-03-01

    The authors describe the case of a 5-year-old girl traumatized from a dog bite to the superior aspect of the orbit in the right eye. The dog's canine tooth penetrated deep into the posterior orbit and severed the attachment of the superior oblique muscle from the globe posterior to the trochlea. The management and clinical course of the patient are described and photographs documenting the initial ocular damage and postoperative course are provided. In addition, the entity known as 'canine tooth syndrome' is reviewed. PMID:15513022

  10. Evaluation of the Broad-Range PCR-Electrospray Ionization Mass Spectrometry (PCR/ESI-MS) System and Virus Microarrays for Virus Detection

    PubMed Central

    Taliaferro, Lanyn P.; Galvin, Teresa A.; Ma, Hailun; Shaheduzzaman, Syed; Williams, Dhanya K.; Glasner, Dustin R.; Khan, Arifa S.

    2014-01-01

    Advanced nucleic acid-based technologies are powerful research tools for novel virus discovery but need to be standardized for broader applications such as virus detection in biological products and clinical samples. We have used well-characterized retrovirus stocks to evaluate the limit of detection (LOD) for broad-range PCR with electrospray ionization mass spectrometry (PCR/ESI-MS or PLEX-ID), RT-PCR assays, and virus microarrays. The results indicated that in the absence of background cellular nucleic acids, PLEX-ID and RT-PCR had a similar LOD for xenotropic murine retrovirus-related virus (XMRV; 3.12 particles per µL) whereas sensitivity of virus detection was 10-fold greater using virus microarrays. When virus was spiked into a background of cellular nucleic acids, the LOD using PLEX-ID remained the same, whereas virus detection by RT-PCR was 10-fold less sensitive, and no virus could be detected by microarrays. Expected endogenous retrovirus (ERV) sequences were detected in cell lines tested and known species-specific viral sequences were detected in bovine serum and porcine trypsin. A follow-up strategy was developed using PCR amplification, nucleotide sequencing, and bioinformatics to demonstrate that an RD114-like retrovirus sequence that was detected by PLEX-ID in canine cell lines (Madin-Darby canine kidney (MDCK) and Cf2Th canine thymus) was due to defective, endogenous gammaretrovirus-related sequences. PMID:24777034

  11. Canine adenovirus downstream processing protocol.

    PubMed

    Puig, Meritxell; Piedra, Jose; Miravet, Susana; Segura, María Mercedes

    2014-01-01

    Adenovirus vectors are efficient gene delivery tools. A major caveat with vectors derived from common human adenovirus serotypes is that most adults are likely to have been exposed to the wild-type virus and exhibit active immunity against the vectors. This preexisting immunity limits their clinical success. Strategies to circumvent this problem include the use of nonhuman adenovirus vectors. Vectors derived from canine adenovirus type 2 (CAV-2) are among the best-studied representatives. CAV-2 vectors are particularly attractive for the treatment of neurodegenerative disorders. In addition, CAV-2 vectors have shown great promise as oncolytic agents in virotherapy approaches and as vectors for recombinant vaccines. The rising interest in CAV-2 vectors calls for the development of scalable GMP compliant production and purification strategies. A detailed protocol describing a complete scalable downstream processing strategy for CAV-2 vectors is reported here. Clarification of CAV-2 particles is achieved by microfiltration. CAV-2 particles are subsequently concentrated and partially purified by ultrafiltration-diafiltration. A Benzonase(®) digestion step is carried out between ultrafiltration and diafiltration operations to eliminate contaminating nucleic acids. Chromatography purification is accomplished in two consecutive steps. CAV-2 particles are first captured and concentrated on a propyl hydrophobic interaction chromatography column followed by a polishing step using DEAE anion exchange monoliths. Using this protocol, high-quality CAV-2 vector preparations containing low levels of contamination with empty viral capsids and other inactive vector forms are typically obtained. The complete process yield was estimated to be 38-45 %. PMID:24132487

  12. Polarization developments

    SciTech Connect

    Prescott, C.Y.

    1993-07-01

    Recent developments in laser-driven photoemission sources of polarized electrons have made prospects for highly polarized electron beams in a future linear collider very promising. This talk discusses the experiences with the SLC polarized electron source, the recent progress with research into gallium arsenide and strained gallium arsenide as a photocathode material, and the suitability of these cathode materials for a future linear collider based on the parameters of the several linear collider designs that exist.

  13. Canine brachycephalic airway syndrome: surgical management.

    PubMed

    Trappler, Michelle; Moore, Kenneth

    2011-05-01

    Many surgical options have been described to treat various aspects of canine brachycephalic airway syndrome (BAS). This article describes the surgical management, postoperative care, and prognosis of this condition. The pathophysiology and medical therapy of BAS are described in a companion article. PMID:21870354

  14. Production of monoclonal antibodies against canine leukocytes.

    PubMed

    Aguiar, Paulo Henrique Palis; Borges dos Santos, Roberto Robson; Lima, Carla Andrade; Rios de Sousa Gomes, Hilton; Larangeira, Daniela Farias; Santos, Patrícia Meira; Barrouin-Melo, Stella Maria; Conrado dos-Santos, Washington Luis; Pontes-de-Carvalho, Lain

    2004-04-01

    A panel of anti-canine leukocyte monoclonal antibodies (MAbs) was produced by immunizing BALB/c mice with canine peripheral blood mononuclear cells (PBMC), either resting or stimulated with concanavalin A (ConA). Three out of 28 clones-IH1, AB6, and HG6-screened by ELISA and producing antibody with the highest specificity for canine cell immunostaining, were subjected to three subsequent subcloning steps by limiting dilution, and selected for further characterization. These MAbs belonged to IgG1 (HG6 and IH1) and IgG2a (AB6) isotypes. The distribution of cell populations expressing the antigen recognized by the antibodies was identified by indirect immunoflorescence on canine PBMC and on tissue sections of lymph node, spleen, liver and skin. The possible crossreactivity with human PBMC was also examined in immunocytochemistry. One of the antibodies specifically recognized macrophages. The MAbs presented here can be foreseen as possible valuable diagnostic and research tools to study immune functions in dogs. PMID:15165486

  15. DELINEATING TOXIC AREAS BY CANINE OLFACTION

    EPA Science Inventory

    A research project was undertaken to learn how the highly acute olfactory sensitivity of the canine could be applied with advantage to environmental problems. The objectives were to determine how dogs could be trained to detect hazardous and toxic pollutants in the environment an...

  16. Experimental Forelimb Allotransplantation in Canine Model.

    PubMed

    Hong, Sa-Hyeok; Eun, Seok-Chan

    2016-01-01

    As reconstructive transplantation is gaining popularity as a viable alternative for upper limb amputees, it is becoming increasingly important for plastic surgeons to renew surgical skills and knowledge of this area. Forelimb allotransplantation research has been performed previously in rodent and swine models. However, preclinical canine forelimb allotransplantation studies are lacking in the literature. The purpose of this paper is to provide an overview of the surgical skills necessary to successfully perform forelimb transplantation in canines as a means to prepare for clinical application. A total of 18 transplantation operations on canines were performed. The recipient limb was shortened at the one-third proximal forearm level. The operation was performed in the following order: bones (two reconstructive plates), muscles and tendons (separately sutured), nerves (median, ulnar, and radial nerve), arteries (two), and veins (two). The total mean time of transplantation was 5 hours ± 30 minutes. All of the animals that received transplantation were treated with FK-506 (tacrolimus, 2 mg/kg) for 7 days after surgery. Most allografts survived with perfect viability without vascular problems during the early postoperative period. The canine forelimb allotransplantation model is well qualified to be a suitable training model for standard transplantation and future research work. PMID:27597952

  17. [Backshifting of lower canines in occlusion regulation].

    PubMed

    Michałowska-Sarosiek, A; Wedrychowska-Szulc, B; Doniec-Zawidzka, I

    1990-08-01

    In 17 patients the lower canines were shifted back during treatment of prognathic malocclusion and cross-bites. Stable devices with retraction loops, rubber or spring traction were used. The duration of active treatment was about 3 months, on average. During the treatment gaps after the removed premolars were closed completely, although this is nearly impossible when removable devices are applied. PMID:2104380

  18. Prostate histotripsy for BPH: initial canine results

    NASA Astrophysics Data System (ADS)

    Roberts, William W.; Hall, Timothy L.; Hempel, Christopher R.; Cain, Charles A.

    2009-02-01

    Histotripsy is an extracorporeal ablative technology that utilizes microsecond pulses of intense ultrasound (< 1% duty cycle) to produce nonthermal, mechanical fractionation of targeted tissue. We have previously demonstrated the feasibility of histotripsy prostate ablation. In this study we sought to assess the chronic tissue response, tolerability and safety of histotripsy in a chronic in vivo canine model. Five acute and thirteen chronic canine subjects were anesthetized and treated with histotripsy targeting the prostate. Pulses consisted of 3 cycle bursts of 750 kHz ultrasound at a repetition rate of 300 Hz delivered transabdominally from a highly focused 15 cm aperture array. Transrectal ultrasound imaging provided accurate targeting and real-time monitoring of histotripsy treatment. Prostates were harvested at 0, 7, 28, or 56 days after treatment. Consistent mechanical tissue fractionation and debulking of prostate tissue was seen acutely and at delayed time points without collateral injury. Urothelialization of the treatment cavity was apparent 28 days after treatment. Canine subjects tolerated histotripsy with minimal hematuria or discomfort. Only mild transient lab abnormalities were noted. Histotripsy is a promising non-invasive therapy for prostate tissue fractionation and debulking that appears safe and well tolerated without systemic side effects in the canine model.

  19. Experimental Forelimb Allotransplantation in Canine Model

    PubMed Central

    2016-01-01

    As reconstructive transplantation is gaining popularity as a viable alternative for upper limb amputees, it is becoming increasingly important for plastic surgeons to renew surgical skills and knowledge of this area. Forelimb allotransplantation research has been performed previously in rodent and swine models. However, preclinical canine forelimb allotransplantation studies are lacking in the literature. The purpose of this paper is to provide an overview of the surgical skills necessary to successfully perform forelimb transplantation in canines as a means to prepare for clinical application. A total of 18 transplantation operations on canines were performed. The recipient limb was shortened at the one-third proximal forearm level. The operation was performed in the following order: bones (two reconstructive plates), muscles and tendons (separately sutured), nerves (median, ulnar, and radial nerve), arteries (two), and veins (two). The total mean time of transplantation was 5 hours ± 30 minutes. All of the animals that received transplantation were treated with FK-506 (tacrolimus, 2 mg/kg) for 7 days after surgery. Most allografts survived with perfect viability without vascular problems during the early postoperative period. The canine forelimb allotransplantation model is well qualified to be a suitable training model for standard transplantation and future research work. PMID:27597952

  20. Polarization Aberrations

    NASA Technical Reports Server (NTRS)

    Mcguire, James P., Jr.; Chipman, Russell A.

    1990-01-01

    The analysis of the polarization characteristics displayed by optical systems can be divided into two categories: geometrical and physical. Geometrical analysis calculates the change in polarization of a wavefront between pupils in an optical instrument. Physical analysis propagates the polarized fields wherever the geometrical analysis is not valid, i.e., near the edges of stops, near images, in anisotropic media, etc. Polarization aberration theory provides a starting point for geometrical design and facilitates subsequent optimization. The polarization aberrations described arise from differences in the transmitted (or reflected) amplitudes and phases at interfaces. The polarization aberration matrix (PAM) is calculated for isotropic rotationally symmetric systems through fourth order and includes the interface phase, amplitude, linear diattenuation, and linear retardance aberrations. The exponential form of Jones matrices used are discussed. The PAM in Jones matrix is introduced. The exact calculation of polarization aberrations through polarization ray tracing is described. The report is divided into three sections: I. Rotationally Symmetric Optical Systems; II. Tilted and Decentered Optical Systems; and Polarization Analysis of LIDARs.

  1. Neuronal polarization.

    PubMed

    Takano, Tetsuya; Xu, Chundi; Funahashi, Yasuhiro; Namba, Takashi; Kaibuchi, Kozo

    2015-06-15

    Neurons are highly polarized cells with structurally and functionally distinct processes called axons and dendrites. This polarization underlies the directional flow of information in the central nervous system, so the establishment and maintenance of neuronal polarization is crucial for correct development and function. Great progress in our understanding of how neurons establish their polarity has been made through the use of cultured hippocampal neurons, while recent technological advances have enabled in vivo analysis of axon specification and elongation. This short review and accompanying poster highlight recent advances in this fascinating field, with an emphasis on the signaling mechanisms underlying axon and dendrite specification in vitro and in vivo. PMID:26081570

  2. Mandibular canine dimensions as an aid in gender estimation

    PubMed Central

    Rajarathnam, Basetty Neelakantam; David, Maria Priscilla; Indira, Annamalai Ponnuswamy

    2016-01-01

    Background: All humans have an identity in life; compassionate societies require this identity to be recognized even after death. Objectives: To measure the dimensions of the mandibular canine and assess the usefulness of the mandibular canine as an aid in gender estimation. Materials and Methods: The study population comprised 200 subjects inclusive of 100 males and 100 females with an age range of 18–25 years. Measurements made in mm at the contact point were of mesiodistal width of the right and left canines and intercanine distance both intraorally and on casts, and the mandibular canine index (MCI) was calculated. The obtained data were subjected to t-test/Mann-Whitney test and discriminant function analysis. Results: All parameters of mandibular canines, namely, intercanine distance, canine width, and canine index were greater in males compared to females suggesting significant sexual dimorphism of mandibular canines. On subjecting the data to discriminant function analysis, it classified sex correctly in 73% of the samples. Conclusion: The result of our study establishes the existence of significant sexual dimorphism in mandibular canines. We can therefore, recommend the use of mandibular canine dimensions as an applicable and additional method for gender determination in human identification. PMID:27555724

  3. Canine cytochrome P450 (CYP) pharmacogenetics

    PubMed Central

    Court, Michael H.

    2013-01-01

    Synopsis The cytochrome P450 (CYP) drug metabolizing enzymes are essential for the efficient elimination of many clinically used drugs. These enzymes typically display high interindividual variability in expression and function resulting from enzyme induction, inhibition, and genetic polymorphism thereby predisposing patients to adverse drug reactions or therapeutic failure. There are also substantial species differences in CYP substrate specificity and expression that complicate direct extrapolation of information from humans to veterinary species. This article reviews the available published data regarding the presence and impact of genetic polymorphisms on CYP-dependent drug metabolism in dogs in the context of known human-dog CYP differences. Canine CYP1A2, which metabolizes phenacetin, caffeine, and theophylline, is the most widely studied polymorphic canine CYP. A single nucleotide polymorphism resulting in a CYP1A2 premature stop codon (c.1117C>T; R383X) with a complete lack of enzyme is highly prevalent in certain dog breeds including Beagle and Irish wolfhound. This polymorphism was shown to substantially affect the pharmacokinetics of several experimental compounds in Beagles during preclinical drug development. However, the impact on the pharmacokinetics of phenacetin (a substrate specific for human CYP1A2) was quite modest probably because other canine CYPs are capable of metabolizing phenacetin. Other canine CYPs with known genetic polymorphisms include CYP2C41 (gene deletion), as well as CYP2D15, CYP2E1, and CYP3A12 (coding SNPs). However the impact of these variants on drug metabolism in vitro or on drug pharmacokinetics is unknown. Future systematic investigations are needed to comprehensively identify CYP genetic polymorphisms that are predictive of drug effects in canine patients. PMID:23890236

  4. Canine visceral leishmaniasis in Sicily.

    PubMed

    Orndorff, G R; Cooper, B A; Smith, W; Ryan, J R

    2000-01-01

    The Sicilian province of Catania is an active foci for human visceral leishmaniasis (VL) in the Mediterranean area. Approximately 10 to 15 cases of VL are diagnosed via hospital admissions each year in this community. Recently, an increase in VL case reporting by Sicilian physicians was noted, with 38 and 37 VL cases in 1996 and 1997, respectively. Before 1995, there were no reported VL cases among U.S. military personnel or their family members living in Sicily. However, since 1996, there have been four cases referred to Walter Reed Army Medical Center for diagnosis and treatment, all involving the children of personnel assigned to Naval Air Station Sigonella. Exposure histories for all infected individuals excluded exposure to Leishmania parasites outside of Sicily. All patients lived in areas where vectoring sandflies are present. All had dogs as family pets. To evaluate the level of infection among dogs owned by Navy personnel and their families, U.S. Navy Environmental and Preventive Medicine Unit 7, in a collaborative study with the U.S. Army Veterinary Clinic, Naval Air Station Sigonella, and the Walter Reed Army Institute of Research, performed clinical evaluation and serological testing of 50 dogs residing with U.S. personnel assigned to Naval Air Station Sigonella. The data indicate a high exposure rate to Leishmania (60% of the animals tested had elevated immunoglobulin M antibody levels) in the study population, suggesting that they were infected with Leishmania infantum. Distribution of seropositive dogs by sex was equal. Most of the dogs studied appeared to be in good health. However, inapparent infection of dogs, seen by Italian veterinarians, has been observed throughout all areas of Catania. Sandflies responsible for vectoring L. infantum were trapped in the same locations as the dogs sampled in this study. The level of subclinical infection was 75% among seropositive dogs. The overall level of canine infection observed was higher than expected

  5. Polar Bear

    USGS Publications Warehouse

    Amstrup, S.D.; DeMaster

    1988-01-01

    Polar bears are long-lived, late-maturing carnivores that have relatively low rates of reproduction and natural mortality. Their populations are susceptible to disturbance from human activities, such as the exploration and development of mineral resources or hunting. Polar bear populations have been an important renewable resource available to coastal communities throughout the Arctic for thousands of years.

  6. Effects of canine serum collected from dogs at different estrous cycle stages on in vitro nuclear maturation of canine oocytes.

    PubMed

    Oh, Hyun Ju; Fibrianto, Yuda Heru; Kim, Min Kyu; Jang, Goo; Hossein, M Shamim; Kim, Hye Jin; Kang, Sung Keun; Lee, Byeong Chun; Hwang, Woo Suk

    2005-08-01

    Canine oocytes are ovulated at prophase of the first meiotic division and undergo maturation in the distal part of the oviduct for at least 48-72 h. Because of these differences from other domestic mammals, the efficiency of in vitro maturation (IVM) of canine oocyte is very low. The present study was conducted to evaluate the effects of canine serum on IVM of canine oocytes recovered from ovaries in various reproductive states (follicular, luteal or anestrous stages). Oocytes were recovered by mincing ovaries from bitches presented for ovariohysterectomy at various stages of the estrous cycle. Heat-inactivated canine serum was prepared with blood taken from dogs at the anestrous, estrous or diestrous stage of the estrous cycle as determined by progesterone concentration and vaginal cytology. Oocytes were cultured for 72 h in tissue culture medium (TCM)-199 supplemented with 10% canine anestrous, estrous or diestrous serum or fetal bovine serum (FBS) (experiment 1), or supplemented with 0 (control), 5%, 10% or 20% canine estrous serum (experiment 2). In experiment 1, IVM of oocytes collected at the follicular stage of the estrous cycle to metaphase II (MII) stage was higher (p < 0.05) with canine estrous serum (14.2%) than with canine anestrous (5.2%) or diestrous serum (6.3%), FBS (2.2%) or in the control (2.2%). In experiment 2, oocytes collected at the follicular stage of the estrous cycle cultured in TCM-199 with 10% canine estrous serum showed a higher maturation rate to MII stage (13.5%, p < 0.05) compared with those cultured with 5% (1.3% MII) or 20% canine estrous serum (5.1% MII) or the control (2.7% MII). In conclusion, our results demonstrate that supplementing culture medium with 10% canine estrous serum improves IVM of canine follicular stage oocytes. PMID:16261767

  7. Canine preprorelaxin: nucleic acid sequence and localization within the canine placenta.

    PubMed

    Klonisch, T; Hombach-Klonisch, S; Froehlich, C; Kauffold, J; Steger, K; Steinetz, B G; Fischer, B

    1999-03-01

    Employing uteroplacental tissue at Day 35 of gestation, we determined the nucleic acid sequence of canine preprorelaxin using reverse transcription- and rapid amplification of cDNA ends-polymerase chain reaction. Canine preprorelaxin cDNA consisted of 534 base pairs encoding a protein of 177 amino acids with a signal peptide of 25 amino acids (aa), a B domain of 35 aa, a C domain of 93 aa, and an A domain of 24 aa. The putative receptor binding region in the N'-terminal part of the canine relaxin B domain GRDYVR contained two substitutions from the classical motif (E-->D and L-->Y). Canine preprorelaxin shared highest homology with porcine and equine preprorelaxin. Northern analysis revealed a 1-kilobase transcript present in total RNA of canine uteroplacental tissue but not of kidney tissue. Uteroplacental tissue from two bitches each at Days 30 and 35 of gestation were studied by in situ hybridization to localize relaxin mRNA. Immunohistochemistry for relaxin, cytokeratin, vimentin, and von Willebrand factor was performed on uteroplacental tissue at Day 30 of gestation. The basal cell layer at the core of the chorionic villi was devoid of relaxin mRNA and immunoreactive relaxin or vimentin but was immunopositive for cytokeratin and identified as cytotrophoblast cells. The cell layer surrounding the chorionic villi displayed specific hybridization signals for relaxin mRNA and immunoreactivity for relaxin and cytokeratin but not for vimentin, and was identified as syncytiotrophoblast. Those areas of the chorioallantoic tissue with most intense relaxin immunoreactivity were highly vascularized as demonstrated by immunoreactive von Willebrand factor expressed on vascular endothelium. The uterine glands and nonplacental uterine areas of the canine zonary girdle placenta were devoid of relaxin mRNA and relaxin. We conclude that the syncytiotrophoblast is the source of relaxin in the canine placenta. PMID:10026098

  8. Polarized rainbow.

    PubMed

    Können, G P; de Boer, J H

    1979-06-15

    The Airy theory of the rainbow is extended to polarized light. For both polarization directions a simple analytic expression is obtained for the intensity distribution as a function of the scattering angle in terms of the Airy function and its derivative. This approach is valid at least down to droplet diameters of 0.3 mm in visible light. The degree of polarization of the rainbow is less than expected from geometrical optics; it increases with droplet size. For a droplet diameter >1 mm the locations of the supernumerary rainbows are equal for both polarization directions, but for a diameter <1 mm the supernumerary rainbows of the weaker polarization component are located between those in the strong component. PMID:20212586

  9. Combined orthodontic-surgical management of a transmigrated mandibular canine.

    PubMed

    Cavuoti, Serena; Matarese, Giovanni; Isola, Gaetano; Abdolreza, Jamilian; Femiano, Felice; Perillo, Letizia

    2016-07-01

    The presence of an impacted mandibular canine is one of the most difficult challenges that an orthodontist will meet. Orthodontic treatment is planned on an individual basis after thoroughly considering the patient's overall facial and dentoskeletal characteristics; the duration, risks, and costs of treatment; patient preferences; and the orthodontist's experience. This article reports an orthodontic treatment of a boy, age 12.9 years, with an impacted mandibular canine in the permanent dentition that was successfully managed. Radiographic analysis indicated a transmigration of the mandibular right canine. The orthodontic treatment plan included extraction of the deciduous right canine followed by surgical exposure and ligation of the permanent canine. Eruption was properly guided, and the correct position of the tooth was achieved. This challenging treatment approach is described in detail, including the mechanics used to align the impacted canine. PMID:26502299

  10. Survivin inhibition via EZN-3042 in canine lymphoma and osteosarcoma.

    PubMed

    Shoeneman, J K; Ehrhart, E J; Charles, J B; Thamm, D H

    2016-06-01

    Canine lymphoma (LSA) and osteosarcoma (OS) have high mortality rates and remain in need of more effective therapeutic approaches. Survivin, an inhibitor of apoptosis (IAP) family member protein that inhibits apoptosis and drives cell proliferation, is commonly elevated in human and canine cancer. Survivin expression is a negative prognostic factor in dogs with LSA and OS, and canine LSA and OS cell lines express high levels of survivin. In this study, we demonstrate that survivin downregulation in canine LSA and OS cells using a clinically applicable locked nucleic acid antisense oligonucleotide (EZN-3042, Enzon Pharmaceuticals, Piscataway Township, NJ, USA) inhibits growth, induces apoptosis and enhances chemosensitivity in vitro, and inhibits survivin transcription and protein production in orthotopic canine OS xenografts. Our findings strongly suggest that survivin-directed therapies might be effective in treatment of canine LSA and OS and support evaluation of EZN-3042 in dogs with cancer. PMID:24923332

  11. Unilateral Maxillary Canine Agenesis: A Case Report and Literature Review

    PubMed Central

    Koç, Nagihan; Çağırankaya, L. Berna; Akkaya, Nursel

    2014-01-01

    Congenital absence of maxillary permanent canines is an extremely rare condition, which may appear as part of a syndrome or as a nonsyndromic form. Nonsyndromic canine agenesis combined with other types of tooth agenesis has occasionally been described in the literature but isolated cases are rarely observed. This report presents an isolated case of maxillary permanent canine agenesis in a healthy 18-year-old female patient and a literature review on the prevalence, etiology, and differential diagnosis of the condition. PMID:25177502

  12. Polar Glaciology

    NASA Technical Reports Server (NTRS)

    Robin, G. D.

    1984-01-01

    Two fields of research on polar ice sheets are likely to be of dominant interest during the 1990s. These are: the role of polar ice sheets in the hydrological cycle ocean-atmosphere-ice sheets-oceans, especially in relation to climate change; and the study and interpretation of material in deep ice cores to provide improved knowledge of past climates and of the varying levels of atmospheric constituents such as CO2, NOx, SO2, aerosols, etc., over the past 200,000 years. Both topics require a better knowledge of ice dynamics. Many of the studies that should be undertaken in polar regions by Earth Observing System require similar instruments and techniques to those used elsewhere over oceans and inland surfaces. However to study polar regions two special requirements need to be met: Earth Observing System satellite(s) need to be in a sufficiently high inclination orbit to cover most of the polar regions. Instruments must also be adapted, often by relatively limited changes, to give satisfactory data over polar ice. The observational requirements for polar ice sheets in the 1990s are summarized.

  13. Myoepithelial cells in canine mammary tumours.

    PubMed

    Sánchez-Céspedes, Raquel; Millán, Yolanda; Guil-Luna, Silvia; Reymundo, Carlos; Espinosa de Los Monteros, Antonio; Martín de Las Mulas, Juana

    2016-01-01

    Mammary tumours are the most common neoplasms of female dogs. Compared to mammary tumours of humans and cats, myoepithelial (ME) cell involvement is common in canine mammary tumours (CMT) of any subtype. Since ME cell involvement in CMT influences both histogenetic tumour classification and prognosis, correct identification of ME cells is important. This review describes immunohistochemical methods for identification of canine mammary ME cells used in vivo. In addition, phenotypic and genotypic methods to isolate ME cells for in vitro studies to analyse tumour-suppressor protein production and gene expression are discussed. The contribution of ME cells to both histogenetic classifications and the prognosis of CMT is compared with other species and the potential use of ME cells as a method to identify carcinoma in situ is discussed. PMID:26639832

  14. Rhabdomyolysis as a complication of canine babesiosis.

    PubMed

    Jacobson, L S; Lobetti, R G

    1996-06-01

    Rhabdomyolysis was diagnosed in two dogs with babesiosis. The first animal presented with muscle pain and caramel-coloured urine, and had markedly elevated serum myoglobin and muscle enzymes. Acute renal failure complicated the clinical picture. The second dog exhibited muscle pain and tremors, together with neurological signs and pulmonary oedema, and died soon after admission. Muscle necrosis and haemorrhage were found at necropsy. In human malaria, a disease clinically similar to canine babesiosis, rhabdomyolysis is unusual, but clinically silent muscle damage appears to be common. Likewise, biochemical evidence of muscle damage is readily found in experimental bovine babesiosis. Muscle enzymes were mildly elevated in three dogs with severe babesiosis and pigmenturia but there was no obvious muscle damage, indicating that this might also apply to canine babesiosis. The pathogenesis of infection-associated rhabdomyolysis and acute renal failure remains unclear, but inflammatory cytokines and nitric oxide could play an important role. PMID:8965483

  15. Characterization of pantropic canine coronavirus from Brazil.

    PubMed

    Pinto, Luciane D; Barros, Iracema N; Budaszewski, Renata F; Weber, Matheus N; Mata, Helena; Antunes, Jéssica R; Boabaid, Fabiana M; Wouters, Angélica T B; Driemeier, David; Brandão, Paulo E; Canal, Cláudio W

    2014-12-01

    Characterization of canine coronavirus (CCoV) strains currently in circulation is essential for understanding viral evolution. The aim of this study was to determine the presence of pantropic CCoV type IIa in tissue samples from five puppies that died in Southern Brazil as a result of severe gastroenteritis. Reverse-transcriptase PCR was used to generate amplicons for sequence analysis. Phylogenetic analysis of the CCoV-IIa strains indicated that they were similar to those found in other countries, suggesting a common ancestor of these Brazilian isolates. This is the first report of pantropic CCoV-II in puppies from Latin America and our findings highlight that CCoV should be included as a differential diagnosis when dogs present with clinical signs and lesions typically seen with canine parvovirus infection. PMID:25294661

  16. Polarizing cues.

    PubMed

    Nicholson, Stephen P

    2012-01-01

    People categorize themselves and others, creating ingroup and outgroup distinctions. In American politics, parties constitute the in- and outgroups, and party leaders hold sway in articulating party positions. A party leader's endorsement of a policy can be persuasive, inducing co-partisans to take the same position. In contrast, a party leader's endorsement may polarize opinion, inducing out-party identifiers to take a contrary position. Using survey experiments from the 2008 presidential election, I examine whether in- and out-party candidate cues—John McCain and Barack Obama—affected partisan opinion. The results indicate that in-party leader cues do not persuade but that out-party leader cues polarize. This finding holds in an experiment featuring President Bush in which his endorsement did not persuade Republicans but it polarized Democrats. Lastly, I compare the effect of party leader cues to party label cues. The results suggest that politicians, not parties, function as polarizing cues. PMID:22400143

  17. Polar motion

    NASA Technical Reports Server (NTRS)

    Kolenkiewicz, R.

    1973-01-01

    Tracking of the Beacon Explorer-C satellite by a precision laser system was used to measure the polar motion and solid earth tide. The tidal perturbation of satellite latitude is plotted as variation in maximum latitude in seconds of arc on earth's surface as a function of the date, and polar motion is shown by plotting the variation in latitude of the laser in seconds of arc along the earth's surface as a function of date

  18. Treatment of canine scabies with milbemycin oxime.

    PubMed

    Miller, W H; de Jaham, C; Scott, D W; Cayatte, S M; Bagladi, M S; Buerger, R G

    1996-04-01

    The purpose of this study was to determine the efficacy of orally administered milbemycin oxime in the treatment of canine scabies. Forty dogs were treated. Mean drug dosage for all dogs was approximately 2 mg/kg body weight. Twenty-seven dogs received 3 doses separated by 7 d, and 13 dogs received 2 doses separated by 14 d. All dogs were clinically normal following treatment and no adverse reactions were detected. PMID:8801016

  19. Ultrasonographic characteristics of canine renal lymphoma.

    PubMed

    Taylor, Angela J; Lara-Garcia, Ana; Benigni, Livia

    2014-01-01

    There is little published information on the ultrasonographic appearance of canine renal lymphoma. The purpose of this retrospective study was to provide additional information regarding the ultrasonographic characteristics of canine renal lymphoma, suggest ultrasonographic description criteria, and evaluate the role of fine-needle aspirate cytology in the diagnosis of this disease. The ultrasonographic features of confirmed renal lymphoma were reviewed in ten dogs. Pyelectasia was found in all dogs. Other ultrasonographic findings were loss of corticomedullary distinction (9/10 dogs), renomegaly (8/10 dogs), renal deformity (6/10 dogs), hypoechoic lesion(s) (6/10 dogs), and hyperechoic lesion(s) (2/10 dogs). Hypoechoic lesions were described as masses, nodules, and indistinct areas. In 30% of the cases (3/10 dogs) ultrasound revealed only minor abnormalities, including grade 1 pyelectasia, mild renomegaly, and focal loss of corticomedullary definition. Bilateral lesions were seen in nine dogs (90%). Renal fine-needle aspirates were performed in 9/10 dogs, yielding a diagnosis in seven on first attempt (78%). Two dogs had been given a provisional cytological diagnosis of round cell neoplasia; in one dog lymphoma was confirmed by second aspirate and by tissue core biopsy in the other. In 1/10 dogs, lymphoma was found at necropsy. Findings indicated that ultrasonographic signs of canine renal lymphoma may be subtle, canine renal lymphoma should be included in the differential diagnosis when the above ultrasonographic features are observed, and fine-needle aspirate cytology is a useful method for diagnosing this disease. PMID:24629062

  20. Remote detection of explosives using trained canines

    SciTech Connect

    Smith, J.C.

    1983-03-01

    Use of dogs is a search method which combines high probability of detection, speed of search, and low cost. It was concluded that the canine could be used for explosive screening of personnel, but that it was imperative that the dog be in a position remote from employees and employee traffic. A study was made of the design of booths and air flow for this purpose. Results of tests and conclusions are given and discussed. (DLC)

  1. Canine kobuviruses in diarrhoeic dogs in Italy.

    PubMed

    Di Martino, Barbara; Di Felice, Elisabetta; Ceci, Chiara; Di Profio, Federica; Marsilio, Fulvio

    2013-09-27

    Canine kobuviruses (CaKVs) are newly recognized picornaviruses recently detected in dogs in the US. By molecular analysis of the whole genome, CaKV that appeared genetically closest to the murine kobuvirus (MuKV) and to the human Aichi virus (AiV), may be classified in the Kobuvirus genus as new genotype (CaKV type 1) within the species Aichivirus A. To date, there are no information on the epidemiology of these novel viruses in other continents. In this study, by screening a collection of 256 dog fecal samples either from diarrhoeic or asymptomatic animals, CaKV was identified in six specimens with an overall prevalence of 2.34% (6/256). All the positive dogs presented diarrhea and were found to be infected by CaKV alone or in mixed infections with canine coronavirus (CCoV) and/or canine parvovirus type 2 (CPV-2). By molecular analysis of the partial 3D gene, all the strains detected displayed a close relatedness with the CaKVs recently identified in the US. This study provides evidence that CaKVs circulate in diarrhoeic dogs in Italy and are not geographically restricted to the North American continent, where they were first signaled. PMID:23806200

  2. Increasing Incidence of Canine Leptospirosis in Switzerland

    PubMed Central

    Major, Andrea; Schweighauser, Ariane; Francey, Thierry

    2014-01-01

    A marked increase in canine leptospirosis was observed in Switzerland over 10 years with a peak incidence of 28.1 diagnosed cases/100,000 dogs/year in the most affected canton. With 95% affected dogs living at altitudes <800 m, the disease presented a seasonal pattern associated with temperature (r2 0.73) and rainfall (r2 0.39), >90% cases being diagnosed between May and October. The increasing yearly incidence however was only weakly correlated with climatic data including number of summer (r2 0.25) or rainy days (r2 0.38). Serovars Australis and Bratislava showed the highest seropositivity rates with 70.5% and 69.1%, respectively. Main clinical manifestations included renal (99.6%), pulmonary (76.7%), hepatic (26.0%), and hemorrhagic syndromes (18.2%), leading to a high mortality rate (43.3%). Similar to the human disease, liver involvement had the strongest association with negative outcome (OR 16.3). Based on these data, canine leptospirosis presents similar features and severity as the human infection for which it therefore can be considered a model. Its re-emergence in a temperate country with very high incidence rates in canines should thus be viewed as a warning and emphasize the need for increased awareness in other species. PMID:25032740

  3. Increasing incidence of canine leptospirosis in Switzerland.

    PubMed

    Major, Andrea; Schweighauser, Ariane; Francey, Thierry

    2014-07-01

    A marked increase in canine leptospirosis was observed in Switzerland over 10 years with a peak incidence of 28.1 diagnosed cases/100,000 dogs/year in the most affected canton. With 95% affected dogs living at altitudes <800 m, the disease presented a seasonal pattern associated with temperature (r2 0.73) and rainfall (r2 0.39), >90% cases being diagnosed between May and October. The increasing yearly incidence however was only weakly correlated with climatic data including number of summer (r2 0.25) or rainy days (r2 0.38). Serovars Australis and Bratislava showed the highest seropositivity rates with 70.5% and 69.1%, respectively. Main clinical manifestations included renal (99.6%), pulmonary (76.7%), hepatic (26.0%), and hemorrhagic syndromes (18.2%), leading to a high mortality rate (43.3%). Similar to the human disease, liver involvement had the strongest association with negative outcome (OR 16.3). Based on these data, canine leptospirosis presents similar features and severity as the human infection for which it therefore can be considered a model. Its re-emergence in a temperate country with very high incidence rates in canines should thus be viewed as a warning and emphasize the need for increased awareness in other species. PMID:25032740

  4. Cytodiagnostics of canine lymphomas - possibilities and limitations.

    PubMed

    Sapierzyński, R; Kliczkowska-Klarowicz, K; Jankowska, U; Jagielski, D

    2016-01-01

    Malignant lymphomas are one of the most common malignant tumours occurring in dogs. The basic method of lymphoma diagnosis in human, as well as in canine oncology is histopathology supported by immunohistochemistry. It was suggested that in veterinary medicine excisional biopsy of lymph node and histopathology should be considered only where the cytologic diagnosis is equivocal or needs to be confirmed. There are at least three basic reasons for which cytological examination ought to be accepted as a sufficient and reliable diagnostic method for lymphoma in dogs. Firstly, most dog owners consider the fine-needle biopsy as an acceptable non-harmful method of sample collection. Secondly, an increasing number of studies recommend cytology as an accurate test for diagnosing and subtyping canine lymphoma. Finally, the vast majority of canine lymphoma subtypes belong to 4-5 categories characterized by a typical cytological picture. Immunocytochemical staining of cytological smears gives new diagnostic possibilities, such as detection of markers better characterizing given growth or a potential goal for target therapy in individual cases (for example inhibitors of platelet-derived growth factor). PMID:27487521

  5. Mechanisms of cell death in canine parvovirus-infected cells provide intuitive insights to developing nanotools for medicine.

    PubMed

    Nykky, Jonna; Tuusa, Jenni E; Kirjavainen, Sanna; Vuento, Matti; Gilbert, Leona

    2010-01-01

    Viruses have great potential as nanotools in medicine for gene transfer, targeted gene delivery, and oncolytic cancer virotherapy. Here we have studied cell death mechanisms of canine parvovirus (CPV) to increase the knowledge on the CPV life cycle in order to facilitate the development of better parvovirus vectors. Morphological studies of CPV-infected Norden laboratory feline kidney (NLFK) cells and canine fibroma cells (A72) displayed characteristic apoptotic events. Apoptosis was further confirmed by activation of caspases and cellular DNA damage. However, results from annexin V-propidium iodide (PI) labeling and membrane polarization assays indicated disruption of the plasma membrane uncommon to apoptosis. These results provide evidence that secondary necrosis followed apoptosis. In addition, two human cancer cell lines were found to be infected by CPV. This necrotic event over apoptotic cell death and infection in human cells provide insightful information when developing CPV as a nanotool for cancer treatments. PMID:20957163

  6. Mechanisms of cell death in canine parvovirus-infected cells provide intuitive insights to developing nanotools for medicine

    PubMed Central

    Nykky, Jonna; Tuusa, Jenni E; Kirjavainen, Sanna; Vuento, Matti; Gilbert, Leona

    2010-01-01

    Viruses have great potential as nanotools in medicine for gene transfer, targeted gene delivery, and oncolytic cancer virotherapy. Here we have studied cell death mechanisms of canine parvovirus (CPV) to increase the knowledge on the CPV life cycle in order to facilitate the development of better parvovirus vectors. Morphological studies of CPV-infected Norden laboratory feline kidney (NLFK) cells and canine fibroma cells (A72) displayed characteristic apoptotic events. Apoptosis was further confirmed by activation of caspases and cellular DNA damage. However, results from annexin V-propidium iodide (PI) labeling and membrane polarization assays indicated disruption of the plasma membrane uncommon to apoptosis. These results provide evidence that secondary necrosis followed apoptosis. In addition, two human cancer cell lines were found to be infected by CPV. This necrotic event over apoptotic cell death and infection in human cells provide insightful information when developing CPV as a nanotool for cancer treatments. PMID:20957163

  7. Elastase Deficiency Phenotype of Pseudomonas aeruginosa Canine Otitis Externa Isolates

    PubMed Central

    Petermann, Shana R.; Doetkott, Curt; Rust, Lynn

    2001-01-01

    Pseudomonas aeruginosa veterinary isolates were assayed for elastase and total matrix protease activity. The elastase activity of canine ear isolates was much less than that of strain PAO1 and that of all other veterinary isolates (P < 0.0001). The results indicate that canine ear isolates have a distinct elastase phenotype. PMID:11329471

  8. Canine evolution in sabretoothed carnivores: natural selection or sexual selection?

    PubMed

    Randau, Marcela; Carbone, Chris; Turvey, Samuel T

    2013-01-01

    The remarkable elongated upper canines of extinct sabretoothed carnivorous mammals have been the subject of considerable speculation on their adaptive function, but the absence of living analogues prevents any direct inference about their evolution. We analysed scaling relationships of the upper canines of 20 sabretoothed feliform carnivores (Nimravidae, Barbourofelidae, Machairodontinae), representing both dirk-toothed and scimitar-toothed sabretooth ecomorphs, and 33 non-sabretoothed felids in relation to body size in order to characterize and identify the evolutionary processes driving their development, using the scaling relationships of carnassial teeth in both groups as a control. Carnassials display isometric allometry in both sabretooths and non-sabretooths, supporting their close relationship with meat-slicing, whereas the upper canines of both groups display positive allometry with body size. Whereas there is no statistical difference in allometry of upper canine height between dirk-toothed and scimitar-toothed sabretooth ecomorphs, the significantly stronger positive allometry of upper canine height shown by sabretooths as a whole compared to non-sabretooths reveals that different processes drove canine evolution in these groups. Although sabretoothed canines must still have been effective for prey capture and processing by hypercarnivorous predators, canine morphology in these extinct carnivores was likely to have been driven to a greater extent by sexual selection than in non-sabretooths. Scaling relationships therefore indicate the probable importance of sexual selection in the evolution of the hypertrophied sabretooth anterior dentition. PMID:23951334

  9. Sex differences in anthropoid mandibular canine lateral enamel formation.

    PubMed

    Guatelli-Steinberg, Debbie; Ferrell, Rebecca J; Spence, Jennifer; Talabere, Tiffany; Hubbard, Amelia; Schmidt, Stacey

    2009-10-01

    Previous research has demonstrated that great ape and macaque males achieve large canine crown sizes primarily through extended canine growth periods. Recent work has suggested, however, that platyrrhine males may achieve larger canine sizes by accelerating rather than prolonging growth. This study tested the hypothesis that the ontogenetic pathway leading to canine sexual dimorphism in catarrhines differs from that of platyrrhines. To test this hypothesis, males and females of several catarrhine genera (Hylobates, Papio, Macaca, Cercopithecus, and Cercocebus) and three platyrrhine genera (Cebus, Ateles, and Callicebus) were compared in the number and spacing of perikymata (enamel growth increments) on their canine crowns. In addition, perikymata periodicities (the number of days of growth perikymata represent) were determined for five genera (Hylobates, Papio, Macaca, Cebus, and Ateles) using previously published as well as original data gathered for this study. The central findings are as follows: 1) males have more perikymata than females for seven of eight genera (in five of the seven, the differences are statistically significant); 2) in general, the greater the degree of sexual dimorphism, the greater the sex difference in male and female perikymata numbers; 3) there is no evidence of a systematic sex difference in primate periodicities; and 4) there is some evidence that sex differences in enamel formation rates may make a minor contribution to canine sexual dimorphism in Papio and Cercopithecus. These findings strongly suggest that in both catarrhines and platyrrhines prolongation of male canine growth is the primary mechanism by which canine crown sexual dimorphism is achieved. PMID:19350641

  10. 9 CFR 113.306 - Canine Distemper Vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.306 Canine Distemper Vaccine. Canine Distemper Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  11. 9 CFR 113.306 - Canine Distemper Vaccine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.306 Canine Distemper Vaccine. Canine Distemper Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  12. 9 CFR 113.306 - Canine Distemper Vaccine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.306 Canine Distemper Vaccine. Canine Distemper Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  13. 9 CFR 113.306 - Canine Distemper Vaccine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.306 Canine Distemper Vaccine. Canine Distemper Vaccine shall be prepared from virus-bearing cell culture fluids or embryonated chicken eggs. Only Master Seed Virus which has been...

  14. 9 CFR 113.306 - Canine Distemper Vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Canine Distemper Vaccine. 113.306 Section 113.306 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Live Virus Vaccines § 113.306 Canine...

  15. First detection of canine parvovirus type 2c in Brazil

    PubMed Central

    Streck, André Felipe; de Souza, Carine Kunzler; Gonçalves, Karla Rathje; Zang, Luciana; Pinto, Luciane Dubina; Canal, Cláudio Wageck

    2009-01-01

    The presence of canine parvovirus type 2 (CPV-2), 2a and 2b has been described in Brazil, however, the type 2c had not been reported until now. In the current study, seven out of nine samples from dogs with diarrhea were characterized as CPV-2c, indicating that this virus is already circulating in the Brazilian canine population. PMID:24031389

  16. Cutaneous immune mechanisms in canine leishmaniosis due to Leishmania infantum.

    PubMed

    Papadogiannakis, E I; Koutinas, A F

    2015-02-15

    Canine leishmaniosis (CanL) caused by the parasite Leishmania infantum is a systemic disease with variable clinical signs. The disease is endemic in the Mediterranean countries and dogs are the main domestic reservoir of the parasite. The quite complicated immune response against the parasite is crucial for the evolution of CanL infection with the skin playing a major role in its immunopathogenesis. After the inoculation of Leishmania promastigotes into the dermis by sand fly bites, complement factors, Langerhan's cells, neutrophils, fibroblasts and keratinocytes are involved in the activation of the innate arm of the skin immune system, with the macrophages and dendritic cells to play a major key role. The effective activation of cellular immunity is the cornerstone of dog's resistance against the parasite. Promastigotes reaching the dermis are engulfed, processed and transferred by APCs to draining lymph nodes to stimulate naïve T-cells for proliferation and differentiation into armed effector T-cells. Th1 cells activate the infected macrophages to kill Leishmania, whereas Th2 cells divert the immune response to humoral immunity and down regulation of cellular immunity with Th1 cell anergy. Inhibition of co-stimulatory molecules expression by infected macrophages contributes to T-cell anergy. In canine subclinical infections cutaneous lymphocytic infiltrate and parasites are absent, as opposed to dogs with clinical leishmaniosis. CD8+ cells constitute a significant population of cellular immunity in CanL since they outnumber CD4+ cells in the dermis, producing IFN-γ in sub clinically infected dogs and high levels of IL-4 in dogs with clinical leishmaniosis. Numerous B-lymphocytes have been shown to heavily infiltrate the dermis at least in exfoliative dermatitis in CanL. A mixed Th1/Th2 cytokine profile has been found in the dermis of naturally infected with L. infantum dogs. In the skin of dogs with clinical leishmaniosis, where plasma cells outnumber T

  17. Cyclooxygenase-2 (COX-2) expression in canine intracranial meningiomas.

    PubMed

    Rossmeisl, J H; Robertson, J L; Zimmerman, K L; Higgins, M A; Geiger, D A

    2009-09-01

    Meningiomas are the most common canine intracranial tumour. Neurologic disability and death from treatment failure remain problematic despite current surgical and radiotherapeutic treatments for canine intracranial meningiomas. Cyclooxygenase-2 (COX-2) over-expression has been demonstrated in multiple canine malignancies, and COX-2 inhibitory treatment strategies have been shown to have both preventative and therapeutic effects in spontaneous and experimental models of cancer. The purpose of this study was to evaluate COX-2 expression in canine intracranial meningiomas. Immunohistochemical and Western blot (WB) analyses showed COX-2 expression in multiple tissues of the normal canine brain, and 87% (21/24) of intracranial meningiomas studied were immunoreactive to COX-2. No significant associations between COX-2 immunoreactivity and tumour grade were identified. Further studies are required to elucidate the physiologic roles of constitutive COX-2 expression in the central nervous system as well as its participation in meningioma tumourigenesis. PMID:19691646

  18. The effects of oncolytic reovirus in canine lymphoma cell lines.

    PubMed

    Hwang, C C; Umeki, S; Igase, M; Coffey, M; Noguchi, S; Okuda, M; Mizuno, T

    2016-08-01

    Reovirus is a potent oncolytic virus in many human neoplasms that has reached phase II and III clinical trials. Our laboratory has previously reported the oncolytic effects of reovirus in canine mast cell tumour (MCT). In order to further explore the potential of reovirus in veterinary oncology, we tested the susceptibility of reovirus in 10 canine lymphoma cell lines. Reovirus-induced cell death, virus replication and infectivity were confirmed in four cell lines with variable levels of susceptibility. The level of Ras activation varied among the cell lines with no correlation with reovirus susceptibility. Reovirus-susceptible cell lines underwent apoptosis as proven by propidium iodide (PI) staining, Annexin V-FITC/PI assay, cleavage of PARP and inhibition of cell death by caspase inhibitor. A single intratumoral injection of reovirus suppressed the growth of canine lymphoma subcutaneous tumour in NOD/SCID mice. Unlike canine MCT, canine lymphoma is less susceptible to reovirus. PMID:25319493

  19. Apicotomy: surgical management of maxillary dilacerated or ankylosed canines.

    PubMed

    Araújo, Eustáquio A; Araújo, Cristiana V; Tanaka, Orlando M

    2013-12-01

    This clinical article reports a technique, apicotomy, for managing dilacerated or ankylosed canines. The records of 3 patients successfully treated with apicotomy are presented. Orthodontists observe clinically significant incidences of impacted maxillary canines in their daily practices. Several procedures have been described to bring an ankylosed, impacted tooth into occlusion. Luxation is the most widely used solution, but there are risks involved with that approach, and the success rate is low. Surgical repositioning has also been used, but morbidity is high, and the aggressiveness of the procedure might also contraindicate it. Ankylosis might be related to the anatomic position of the canine's root apex and its adjacent anatomic structures. Apicotomy is a guided fracture of a canine root apex, followed by its orthodontic traction. It is a conservative surgical alternative for treating impacted canines with dilacerations or apical root ankylosis. PMID:24286914

  20. Recombinant canine distemper virus serves as bivalent live vaccine against rabies and canine distemper.

    PubMed

    Wang, Xijun; Feng, Na; Ge, Jinying; Shuai, Lei; Peng, Liyan; Gao, Yuwei; Yang, Songtao; Xia, Xianzhu; Bu, Zhigao

    2012-07-20

    Effective, safe, and affordable rabies vaccines are still being sought. Attenuated live vaccine has been widely used to protect carnivores from canine distemper. In this study, we generated a recombinant canine distemper virus (CDV) vaccine strain, rCDV-RVG, expressing the rabies virus glycoprotein (RVG) by using reverse genetics. The recombinant virus rCDV-RVG retained growth properties similar to those of vector CDV in Vero cell culture. Animal studies demonstrated that rCDV-RVG was safe in mice and dogs. Mice inoculated intracerebrally or intramuscularly with rCDV-RVG showed no apparent signs of disease and developed a strong rabies virus (RABV) neutralizing antibody response, which completely protected mice from challenge with a lethal dose of street virus. Canine studies showed that vaccination with rCDV-RVG induced strong and long-lasting virus neutralizing antibody responses to RABV and CDV. This is the first study demonstrating that recombinant CDV has the potential to serve as bivalent live vaccine against rabies and canine distemper in animals. PMID:22698451

  1. Breed predisposition to canine gastric carcinoma - a study based on the Norwegian canine cancer register

    PubMed Central

    2013-01-01

    Background Previous research has indicated a breed predisposition to gastric carcinoma in dogs. However, results to date are inconsistent since several studies have failed to prove such a predisposition. Better knowledge of breeds at risk could facilitate early detection of gastric carcinoma in dogs. The aim of the study was to retrospectively investigate the proportion and possible breed predisposition to canine gastric carcinoma using the Norwegian Canine Cancer Register for calculations of proportional morbidity ratios (PMRs) for the period 1998–2009. Results Histologically verified tumours recorded in the Norwegian Canine Cancer Register were studied (n = 19,715). A total of 31 (0.16%) cases of canine gastric carcinomas were identified. The median age of affected dogs was 10 years. The most commonly reported clinical signs were vomiting, anorexia, and weight loss. Males had significantly higher odds of gastric carcinoma than females (P = 0.02). The PMR with 95% confidence interval (CI) was calculated for each breed, and a breed predisposition was identified. Individuals of the breeds Tervuren (PMR 56.1), Bouvier des Flandres (PMR 36.5), Groenendael (PMR 34.5), Collie (PMR 26.1), Standard poodle (PMR 7.6), and Norwegian elkhound (PMR 6.1) had a significantly increased risk of developing gastric carcinoma. Discussion and conclusion The proportion of cases of gastric carcinoma recorded in the Norwegian Canine Cancer Register was found to be 0.16%, and a breed predisposition was identified. The breed predisposition observed in the current study indicates a genetic susceptibility to gastric carcinoma. PMID:23514604

  2. Political polarization

    PubMed Central

    Dixit, Avinash K.; Weibull, Jörgen W.

    2007-01-01

    Failures of government policies often provoke opposite reactions from citizens; some call for a reversal of the policy, whereas others favor its continuation in stronger form. We offer an explanation of such polarization, based on a natural bimodality of preferences in political and economic contexts and consistent with Bayesian rationality. PMID:17452633

  3. Polar Stratigraphy

    NASA Technical Reports Server (NTRS)

    1999-01-01

    These three images were taken on three different orbits over the north polar cap in April 1999. Each shows a different part of the same ice-free trough. The left and right images are separated by a distance of more than 100 kilometers (62 miles). Note the similar layers in each image.

  4. Extraglandular and intraglandular vascularization of canine prostate.

    PubMed

    Stefanov, Miroslav

    2004-03-01

    The literature on the vascularization of the canine prostate is reviewed and the clinical significance of prostate morphology is described. Scanning Electron Microscopy (SEM), combined with improved corrosion casting methods, reveal new morphological details that promise better diagnostics and treatment but also require expansion of clinical nomenclature. A proposal is made for including two previously unnamed veins in Nomina Anatomica Veterinaria (NAV). The canine prostate has two lobes with independent vascularization. Each lobe is supplied through the left and right a. prostatica, respectively. The a. prostatica sprouts three small vessels (cranial, middle, and caudal) towards the prostate gland. A. prostatica is a small-size artery whose wall structure is similar to the arteries of the muscular type. V. prostatica is a small-size valved vein. The canine prostate has capsular, parenchymal, and urethral vascular zones. The surface vessels of the capsule are predominantly veins and the diameter of arterial vessels is larger than that of the veins. The trabecular vessels are of two types: direct and branched. The prostate parenchyma is supplied by branches of the trabecular vessels. The periacinary capillaries are fenestrated and form a net in a circular pattern. The processes of the myoepithelial cells embrace both the acins and the periacinar capillaries. In the prostate ductal system. there are spermatozoa. The prostatic part of the urethra is supplied by an independent branch of a. prostatica. The prostatic urethral part is drained by v. prostatica, the vein of the urethral bulb and the ventral prostate veins. M. urethralis begins as early as the urethral prostatic part. The greater part of the white muscle fibers in m. urethralis suggest an enhanced anaerobic metabolism. PMID:14988915

  5. Canine hip extension range during gait.

    PubMed

    van der Walt, A M; Stewart, A V; Joubert, K E; Bekker, P

    2008-12-01

    Assessment of canine gait is frequently used by veterinary clinicians to establish the presence of orthopaedic pain. As up to 30% of canine orthopaedic conditions affect the pelvic limb, knowledge of pelvic limb biomechanics during gait is very important. Previous studies have investigated the biomechanics at the tarsus and stifle, but little information is available regarding hip motion during gait. The aim of this study was to determine the maximum hip extension range achieved during the stance phase of gait in normal canines. In addition, this study aimed to determine the difference between maximum passive hip extension and maximum hip extension during gait. Using a sample of 30 morphologically similar normal dogs, mean maximum passive hip extension was measured using a goniometer and mean maximum hip extension range during gait was determined videographically. Inter- and intra-assessor reliability studies performed at the start of the study showed that the measurement tools and techniques used in this study were valid and reliable. The goniometric data showed that mean maximum passive hip extension range was 162.44 degrees (+/-3.94) with no significant difference between the left and the right hind limbs. The videographic data showed that mean maximum hip extension range during gait was 119.9 degrees (+/-9.26) with no significant difference between the left and right hind limbs. The results of this study provided reference values for active and passive hip extension range and showed that the degree of hip extension range required for normal gait is significantly less than maximum passive hip extension range. PMID:19496317

  6. Diagnosis and management of canine claw diseases.

    PubMed

    Mueller, R S

    1999-11-01

    The diagnostic workup for canine claw disease consists of a good history and complete clinical examination which may provide clues for a possible underlying disorder. In dogs with claw disease but no other clinical or historical signs, further recommended diagnostic procedures include cytological evaluation of impression smears or discharge from the claw fold, bacterial culture and sensitivity testing, biopsy of the claw matrix, and an elimination diet for 6 to 8 weeks. If no underlying disease can be identified, trial treatment with essential fatty acid supplementation, vitamin E, or a combination of doxycycline hydrochloride and niacinamide may be useful. In some patients, onychectomy of all claws may be considered. PMID:10563005

  7. Definition, Classification, and Pathophysiology of Canine Glaucoma.

    PubMed

    Pizzirani, Stefano

    2015-11-01

    Glaucoma is a common ocular condition in humans and dogs leading to optic nerve degeneration and irreversible blindness. Primary glaucoma is a group of spontaneous heterogeneous diseases. Multiple factors are involved in its pathogenesis and these factors vary across human ethnic groups and canine breeds, so the clinical phenotypes are numerous and their classification can be challenging and remain superficial. Aging and oxidative stress are major triggers for the manifestation of disease. Multiple, intertwined inflammatory and biochemical cascades eventually alter cellular and extracellular physiology in the optic nerve and trabecular meshwork and lead to vision loss. PMID:26456751

  8. The Genetics of Canine Skull Shape Variation

    PubMed Central

    Schoenebeck, Jeffrey J.; Ostrander, Elaine A.

    2013-01-01

    A dog’s craniofacial diversity is the result of continual human intervention in natural selection, a process that began tens of thousands of years ago. To date, we know little of the genetic underpinnings and developmental mechanisms that make dog skulls so morphologically plastic. In this Perspectives, we discuss the origins of dog skull shapes in terms of history and biology and highlight recent advances in understanding the genetics of canine skull shapes. Of particular interest are those molecular genetic changes that are associated with the development of distinct breeds. PMID:23396475

  9. Canine congenital portosystemic shunts: Disconnections dissected.

    PubMed

    Van den Bossche, L; van Steenbeek, F G

    2016-05-01

    Canine congenital portosystemic shunts (CPSS) are vascular anomalies that connect the portal vein with the systemic circulation, therefore bypassing the hepatic parenchyma. Portosystemic shunts exist in two different subtypes: extrahepatic and intrahepatic. This congenital disorder is also described in mice, cat, sheep and man. Research has been focused on pathophysiology, diagnostics and treatment of CPSS and this has resulted in increased knowledge, although the aetiology of the disease remains unclear. This review focuses on the aetiology and genetic basis of both intra- and extrahepatic shunts. PMID:27061656

  10. Canine blood groups: description of 20 specificities.

    PubMed

    Symons, M; Bell, K

    1992-01-01

    Twenty blood typing reagents, four agglutinins and 16 operable in the antiglobulin test, were prepared from 54 antisera which were produced in 24 dogs. Two of the reagents were identified as anti-B and Nf6. Two of the antigens were shown by absorption and family studies to be linear subtypes. In most cases, detailed family studies demonstrated a Mendelian dominant inheritance for the genes controlling the canine red cell antigens. Gene frequencies were determined in various breeds of dogs and in the dingo. PMID:1492701