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Sample records for intestinal brush border

  1. Immunoelectrophoretic studies on pig intestinal brush border proteins

    DEFF Research Database (Denmark)

    Danielsen, Erik Michael; Sjöström, H; Norén, O

    1977-01-01

    Brush borders were prepared from pig intestinal mucosa and the membrane proteins solubilized with either Triton X-100 or papain. Proteins, thus released, were used as antigens to raise antisera in rabbits. The immunoglobulin G fractions were isolated and shown by the double layer immunofluorescence...

  2. Galectin-4 and small intestinal brush border enzymes form clusters.

    Science.gov (United States)

    Danielsen, E M; van Deurs, B

    1997-11-01

    Detergent-insoluble complexes prepared from pig small intestine are highly enriched in several transmembrane brush border enzymes including aminopeptidase N and sucrase-isomaltase, indicating that they reside in a glycolipid-rich environment in vivo. In the present work galectin-4, an animal lectin lacking a N-terminal signal peptide for membrane translocation, was discovered in these complexes as well, and in gradient centrifugation brush border enzymes and galectin-4 formed distinct soluble high molecular weight clusters. Immunoperoxidase cytochemistry and immunogold electron microscopy showed that galectin-4 is indeed an intestinal brush border protein; we also localized galectin-4 throughout the cell, mainly associated with membraneous structures, including small vesicles, and to the rootlets of microvillar actin filaments. This was confirmed by subcellular fractionation, showing about half the amount of galectin-4 to be in the microvillar fraction, the rest being associated with insoluble intracellular structures. A direct association between the lectin and aminopeptidase N was evidenced by a colocalization along microvilli in double immunogold labeling and by the ability of an antibody to galectin-4 to coimmunoprecipitate aminopeptidase N and sucrase-isomaltase. Furthermore, galectin-4 was released from microvillar, right-side-out vesicles as well as from mucosal explants by a brief wash with 100 mM lactose, confirming its extracellular localization. Galectin-4 is therefore secreted by a nonclassical pathway, and the brush border enzymes represent a novel class of natural ligands for a member of the galectin family. Newly synthesized galectin-4 is rapidly "trapped" by association with intracellular structures prior to its apical secretion, but once externalized, association with brush border enzymes prevents it from being released from the enterocyte into the intestinal lumen.

  3. Galectin-4 and small intestinal brush border enzymes form clusters

    DEFF Research Database (Denmark)

    Danielsen, E M; van Deurs, B

    1997-01-01

    that galectin-4 is indeed an intestinal brush border protein; we also localized galectin-4 throughout the cell, mainly associated with membraneous structures, including small vesicles, and to the rootlets of microvillar actin filaments. This was confirmed by subcellular fractionation, showing about half...... lacking a N-terminal signal peptide for membrane translocation, was discovered in these complexes as well, and in gradient centrifugation brush border enzymes and galectin-4 formed distinct soluble high molecular weight clusters. Immunoperoxidase cytochemistry and immunogold electron microscopy showed...... the amount of galectin-4 to be in the microvillar fraction, the rest being associated with insoluble intracellular structures. A direct association between the lectin and aminopeptidase N was evidenced by a colocalization along microvilli in double immunogold labeling and by the ability of an antibody...

  4. Galectin-4 and small intestinal brush border enzymes form clusters

    DEFF Research Database (Denmark)

    Danielsen, E M; van Deurs, B

    1997-01-01

    to galectin-4 to coimmunoprecipitate aminopeptidase N and sucrase-isomaltase. Furthermore, galectin-4 was released from microvillar, right-side-out vesicles as well as from mucosal explants by a brief wash with 100 mM lactose, confirming its extracellular localization. Galectin-4 is therefore secreted...... that galectin-4 is indeed an intestinal brush border protein; we also localized galectin-4 throughout the cell, mainly associated with membraneous structures, including small vesicles, and to the rootlets of microvillar actin filaments. This was confirmed by subcellular fractionation, showing about half...

  5. Kinetics of the intestinal brush border proline (Imino) carrier.

    Science.gov (United States)

    Stevens, B R; Wright, E M

    1987-05-15

    The kinetics of L-proline transport across intestinal brush borders via the Imino carrier were studied using membrane vesicles. The Imino carrier is defined as the agent responsible for L-alanine insensitive. Na+-dependent uptake of L-proline. Initial rate measurements were made under voltage clamped conditions (pD = 0) to investigate L-proline transport as a function of cis and trans Na+ and proline concentrations. Under zero-trans conditions, increasing cis Na+ activated proline uptake with a Hill coefficient of 1.7 and decreased the apparent Kt with no change in Jimax. The Jimax was approximately 60 pmol mg-1 s-1 and the apparent Kt ranged from 0.25 mM at cis Na = 100 to 1.0 mM at cis Na+ = 30 mM. Trans Na inhibited proline uptake via a reduction in Jimax. Trans proline had no significant effect in the absence of trans Na+, but it relieved the trans Na+ inhibition. Under equilibrium exchange conditions, the Jimax was twice that observed under zero-trans conditions. These kinetics of L-proline transport suggest a model in which uptake occurs by a rapid equilibrium iso-ordered ter ter system. Two Na+ ions bind first to the carrier on the cis face of the membrane to increase the affinity of the carrier for proline. The fully loaded complex then isomerizes to release the substrates to the trans side. The partially loaded Na+-only forms are unable to translocate across the membrane. A rate-limiting step appears to be the isomerization of unloaded carrier from the trans to the cis side of the membrane.

  6. The possible role of pancreatic proteases in the turnover of intestinal brush border proteins.

    Science.gov (United States)

    Alpers, D H; Tedesco, F J

    1975-08-05

    1. Intestinal brush border enzymes have heterogeneous rates of turnover, the largest proteins having the fastest turnover. Since the membrane faces the intestinal lumen, the effects of pancreatic factors were examined in mediating this turnover. Surgical subtotal pancreatectomy was used as an experimental model to study the turnover of brush border proteins in the absence of most pancreatic secretions. 2. Subtotal (95%) pancreatectomy of rats was found to cause elevations by about 50% of total activity and specific activities of certain brush border enzymes (maltase, sucrase, lactase), but not of others (alkaline phosphatase, trehalase). Rats were judged to be functionally deficient in pancreatic proteolytic enzymes (a) by demonstration of vitamin B-12 malabsorption, which was corrected by trypsin, and (b) by the finding of only about 20% of proteolytic activity appearing in the lumen after a test meal when compared to control. 3. To measure protein turnover in vivo the method of double labelling was used, where [3H]- and [14C]valine were administered intraduodenally in sequence 10 h apart. With this technique, a high 3H/14C ratio is correlated with rapid turnover. Proteins with apparent molecular weights of about 200 000-270 000 were found to turn over more rapidly than smaller proteins. 3H/14C ranged from 4.7 to 6.2 in animals without pancreatic insufficiency. In the face of decreased pancreatic proteolysis, the 3H/14C ratio was 2.3-3.1, similar to that of proteins with a slow half life. 4. Estimates of relative synthetic rates of large brush border proteins were lower than normal in pancreatectomized animals, but were constant over the period of the labelling experiment. The high enzyme levels in the face of lower synthetic rates confirms that, at the new steady rate, degradation rates must be slower for large brush border proteins in pancreatic insufficiency. 5. In vitro, using purified brush borders, unfractionated pancreatic enzymes were found to remove

  7. Post-translational suppression of expression of intestinal brush border enzymes by fructose

    DEFF Research Database (Denmark)

    Danielsen, E M

    1989-01-01

    The two major dietary sugars, fructose and sucrose, were found to suppress effectively the biosynthetic renewal of brush border enzymes in the gut. When studied in cultured explants of pig small intestine mucosa, 10-50 mM concentrations of fructose completely prevented the expression of mature...... aminopeptidase N and severely reduced that of sucrase-isomaltase. The instantly occurring and reversible suppressive effect manifested itself as a leupeptin-sensitive degradation of newly synthesized brush border enzymes. The likely mechanism of action of the dietary sugar is by causing an abnormal...... cotranslational glycosylation that in turn triggers a rapid proteolytic breakdown. Our findings suggest that renewal of digestive brush border enzymes is transiently suppressed during intake of fructose- or sucrose-rich meals....

  8. Post-translational suppression of expression of intestinal brush border enzymes by fructose

    DEFF Research Database (Denmark)

    Danielsen, E M

    1989-01-01

    The two major dietary sugars, fructose and sucrose, were found to suppress effectively the biosynthetic renewal of brush border enzymes in the gut. When studied in cultured explants of pig small intestine mucosa, 10-50 mM concentrations of fructose completely prevented the expression of mature am...... cotranslational glycosylation that in turn triggers a rapid proteolytic breakdown. Our findings suggest that renewal of digestive brush border enzymes is transiently suppressed during intake of fructose- or sucrose-rich meals.......The two major dietary sugars, fructose and sucrose, were found to suppress effectively the biosynthetic renewal of brush border enzymes in the gut. When studied in cultured explants of pig small intestine mucosa, 10-50 mM concentrations of fructose completely prevented the expression of mature...... aminopeptidase N and severely reduced that of sucrase-isomaltase. The instantly occurring and reversible suppressive effect manifested itself as a leupeptin-sensitive degradation of newly synthesized brush border enzymes. The likely mechanism of action of the dietary sugar is by causing an abnormal...

  9. Effects of divalent cations on vitamin B12 adsorption to brush borders of rat intestine

    International Nuclear Information System (INIS)

    Miyata, Satoru; Inada, Masami

    1976-01-01

    A brush border preparation from rat intestine was incubated with rat intrinsic factor-vitamin B 12 complex in 0.01M Tris-HCl buffer, pH 7.4. The 57 Co-B 12 uptake to brush borders was proportional to the amount of protein or to alkaline phosphatase activity in the preparations. The uptake increased with time of incubation. At 37 0 C, the uptake after incubation for 15 min. was 80-85% of that for one hr. The uptake at 4 0 C was approximately 70% of that at 37 0 C. There was no difference as a result of adding glucose to the incubation medium. The uptake was observed in the alkaline environment above pH 6.3. Maximum uptake occurred at pH 8.0. Brush borders washed with Krebs-Ringer bicarbonate buffer (pH 7.4) exhibited no difference in B 12 uptake, whether in the presence of absence of calcium ion. But brush borders washed with ethylenediaminetetraacetate exhibited no uptake when incubated in calcium-free medium. The uptake reached a maximum by addition of calcium ion at a concentration of 0.3 mM, and was not alter up to 10 mM. Addition of magnesium ion exhibited no uptake. Calcium-dependent B 12 uptake was markedly inhibited by manganese ion. Magnesium ion seemed to slightly inhibit the calcium-dependent uptake. (auth.)

  10. Involvement of detergent-insoluble complexes in the intracellular transport of intestinal brush border enzymes

    DEFF Research Database (Denmark)

    Danielsen, E M

    1995-01-01

    A number of transmembrane digestive enzymes of the porcine small intestinal brush border membrane were found to be partially Triton X-100-insoluble at 0 degree C and colocalized in gradient centrifugation experiments with the GPI-anchored alkaline phosphatase in low-density, detergent-insoluble c......A number of transmembrane digestive enzymes of the porcine small intestinal brush border membrane were found to be partially Triton X-100-insoluble at 0 degree C and colocalized in gradient centrifugation experiments with the GPI-anchored alkaline phosphatase in low-density, detergent......-insoluble complexes commonly known as glycolipid "rafts". Thus, aminopeptidase N (EC 3.4.11.2), aminopeptidase A (EC 3.4.11.7), dipeptidyl peptidase IV (EC 3.4.14.5), and sucrase-isomaltase (EC 3.2.1.48-10) were 34-48% detergent-insoluble. Maltase-glucoamylase (EC 3.2.1.20) was markedly less detergent-insoluble (20......%), and lactase-phlorizin hydrolase (EC 3.2.1.23-62) was essentially fully soluble in detergent. In radioactively labeled, mucosal explants, the newly synthesized brush border enzymes began to associate with detergent-insoluble complexes while still in their transient, high mannose-glycosylated form...

  11. Small molecule pinocytosis and clathrin-dependent endocytosis at the intestinal brush border

    DEFF Research Database (Denmark)

    Danielsen, Erik Michael; Hansen, Gert H

    2016-01-01

    Pinocytosis at the small intestinal brush border was studied in postweaned porcine cultured mucosal explants, using the fluorescent polar probes Alexa hydrazide (AH, MW 570), Texas red dextran (TRD, MW ~ 3000), and Cascade blue dextran (CBD, MW ~ 10,000). Within 1 h, AH appeared in a string...... of subapical punctae in enterocytes, indicative of an ongoing constitutive pinocytosis. By comparison, TRD was taken up less efficiently into the same compartment, and no intracellular labeling of CBD was detectable, indicating that only small molecules are pinocytosed from the postweaned gut lumen. AH...

  12. The Secretion and Action of Brush Border Enzymes in the Mammalian Small Intestine.

    Science.gov (United States)

    Hooton, Diane; Lentle, Roger; Monro, John; Wickham, Martin; Simpson, Robert

    2015-01-01

    Microvilli are conventionally regarded as an extension of the small intestinal absorptive surface, but they are also, as latterly discovered, a launching pad for brush border digestive enzymes. Recent work has demonstrated that motor elements of the microvillus cytoskeleton operate to displace the apical membrane toward the apex of the microvillus, where it vesiculates and is shed into the periapical space. Catalytically active brush border digestive enzymes remain incorporated within the membranes of these vesicles, which shifts the site of BB digestion from the surface of the enterocyte to the periapical space. This process enables nutrient hydrolysis to occur adjacent to the membrane in a pre-absorptive step. The characterization of BB digestive enzymes is influenced by the way in which these enzymes are anchored to the apical membranes of microvilli, their subsequent shedding in membrane vesicles, and their differing susceptibilities to cleavage from the component membranes. In addition, the presence of active intracellular components of these enzymes complicates their quantitative assay and the elucidation of their dynamics. This review summarizes the ontogeny and regulation of BB digestive enzymes and what is known of their kinetics and their action in the peripheral and axial regions of the small intestinal lumen.

  13. Involvement of detergent-insoluble complexes in the intracellular transport of intestinal brush border enzymes

    DEFF Research Database (Denmark)

    Danielsen, E M

    1995-01-01

    was apparent after only 1 h of labeling, where aminopeptidase N, sucrase-isomaltase, and alkaline phosphatase together comprised 25-30% of the total labeled, detergent-insoluble proteins, showing that sorting of newly made brush border membrane proteins into the glycolipid "rafts" does take place...... intracellularly. I therefore propose that, in the enterocyte, the brush border enzymes are targeted directly from the trans-Golgi network toward the apical cell surface....

  14. Methionine and glucose transport by isolated intestinal brush border membrane vesicles from pigs and lambs fed an Aspergillus product

    OpenAIRE

    Jang, Insurk

    1993-01-01

    This study was designed to determine whether feeding an Aspergillus product would influence growth or feed utilization and intestinal mucosal cell function as indicated by uptake of methionine and glucose by isolated intestinal brush border membrane vesicles (BBMV). In Experiment 1, 24 weanling pigs were paired by sex, BW, and litter and were allotted, within pairs, to either an 18% CP corn-soy diet (control) or the same diet supplemented (.15%) with an Aspergillus product. There were no diff...

  15. Brush border Myosin Ia has tumor suppressor activity in the intestine

    Science.gov (United States)

    Mazzolini, Rocco; Dopeso, Higinio; Mateo-Lozano, Silvia; Chang, Wakam; Rodrigues, Paulo; Bazzocco, Sarah; Alazzouzi, Hafid; Landolfi, Stefania; Hernández-Losa, Javier; Andretta, Elena; Alhopuro, Pia; Espín, Eloy; Armengol, Manel; Tabernero, Josep; Ramón y Cajal, Santiago; Kloor, Matthias; Gebert, Johannes; Mariadason, John M.; Schwartz, Simo; Aaltonen, Lauri A.; Mooseker, Mark S.; Arango, Diego

    2012-01-01

    The loss of the epithelial architecture and cell polarity/differentiation is known to be important during the tumorigenic process. Here we demonstrate that the brush border protein Myosin Ia (MYO1A) is important for polarization and differentiation of colon cancer cells and is frequently inactivated in colorectal tumors by genetic and epigenetic mechanisms. MYO1A frame-shift mutations were observed in 32% (37 of 116) of the colorectal tumors with microsatellite instability analyzed, and evidence of promoter methylation was observed in a significant proportion of colon cancer cell lines and primary colorectal tumors. The loss of polarization/differentiation resulting from MYO1A inactivation is associated with higher tumor growth in soft agar and in a xenograft model. In addition, the progression of genetically and carcinogen-initiated intestinal tumors was significantly accelerated in Myo1a knockout mice compared with Myo1a wild-type animals. Moreover, MYO1A tumor expression was found to be an independent prognostic factor for colorectal cancer patients. Patients with low MYO1A tumor protein levels had significantly shorter disease-free and overall survival compared with patients with high tumoral MYO1A (logrank test P = 0.004 and P = 0.009, respectively). The median time-to-disease recurrence in patients with low MYO1A was 1 y, compared with >9 y in the group of patients with high MYO1A. These results identify MYO1A as a unique tumor-suppressor gene in colorectal cancer and demonstrate that the loss of structural brush border proteins involved in cell polarity are important for tumor development. PMID:22307608

  16. Effect of maternal diabetes on postnatal development of brush border enzymes and transport functions in rat intestine.

    Science.gov (United States)

    Sharma, Ruchi; Kaur, Jyotdeep; Mahmood, Akhtar

    2009-07-01

    The effect of alloxan-induced maternal diabetes has been studied on the postnatal development of brush border enzymes in rat intestine. Diabetes was induced by injecting alloxan in rat mothers on day 3 of gestation. There was no change in gestational period (22 days) in control and diabetic groups; however, the litter size was reduced (P border enzymes revealed elevated levels of lactase (76%), sucrase (46%), maltase (25%), trehalase (38%), alkaline phosphatase (57%), and leucine aminopeptidase (56%) up to 21 days of postnatal age in diabetic group compared with controls. However, in 30- to 45-day-old animals, the enzyme levels were either reduced in diabetic group or there was no change compared with controls. Western blot analysis corroborated the enzyme analysis data in purified brush borders. Also, 45 days after birth, the intestinal uptake of D-glucose and glycine was significantly high (30%-61%) in pups from diabetic dams compared with controls. These findings indicate that alloxan-induced maternal diabetes influences the postnatal development of intestine and the expression of various brush border enzymes and transport functions in rat intestine. This could affect the growth and development of the offspring during the postnatal period.

  17. Role of intestinal brush border peptidases in the simulated digestion of milk proteins.

    Science.gov (United States)

    Picariello, Gianluca; Miralles, Beatriz; Mamone, Gianfranco; Sánchez-Rivera, Laura; Recio, Isidra; Addeo, Francesco; Ferranti, Pasquale

    2015-05-01

    This study aimed to assess the impact of the "often neglected" intestinal brush border membranes (BBMs) hydrolases on dietary peptides, exploring the possibility that the disintegration of proteins progressed in the small intestine up to a "core" of intrinsically stable oligopeptides, persisting independently on the up-stream breakdown. Samples of sodium caseinate, skim milk powder, and whey protein isolate were submitted to in vitro simulated gastropancreatic digestion using two different procedures: (i) a simplified model involving the main compartmental specific proteases; (ii) a static digestion method based on a frameset of parameters inferred from in vivo. The gastroduodenal digesta were further hydrolyzed with peptidases from porcine jejunal BBM. The peptidomes arising from the two digestion models, characterized by combined HPLC and MS techniques, differed to some extent. However, only specific protein domains survived digestion, among which are potential bioactive or immunogenic (food allergy) peptides. The degree of hydrolysis (DH) after BBM digestion (70-77%) practically did not differ between the digestion models and significantly increased the DH after duodenal steps. Any in vitro digestion model should be supplemented with a jejunal phase to realistically determine the bioaccessibility and bioavailability of dietary peptides. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Modulation of intestinal brush border membrane chemical composition during postnatal development in rats: effect of gestational diabetes.

    Science.gov (United States)

    Sharma, Ruchi; Chauhan, Shailender Singh; Mahmood, Akhtar

    2012-01-01

    There was a significant increase in fucose (52%), total hexoses (16%) and hexosamine (56%) except sialic acid, which was reduced (77%) in the microvillus membrane of infants born to rat mothers made diabetic by injecting alloxan on day 3 of gestation. Expressed on the protein basis there were a significant increase in membrane, triglyceride, total cholesterol, and phospholipids content of brush border in pups from diabetic group between 5-45 days of postnatal age. Intestinal morphology in diabetic group showed, regression of tubular glands, distorted cellular organization of mucosal cells, reduction in the mucosal cell height and number of secretory goblet cells. These findings suggest that the gestational diabetes affects the sugar and lipid composition of the intestinal brush border membrane in rats during early stages of the postnatal development, which may be associated with compromised tissue functions later in life.

  19. Modifications in the brush border enzymes of the small intestine after irradiation at different times of the day

    Energy Technology Data Exchange (ETDEWEB)

    Becciolini, A.; Lanini, A.; Giache, V.; Balzi, M.; Bini, R. (Florence Univ. (Italy). Ist. di Radiologia)

    1982-01-01

    The behaviour of the brush border enzyme activity of the intestinal epithelium after the same sublethal radiation dose to the abdomen at different times of the day was investigated. Three previously observed post-irradiation phases (initial increase of activity, reduction, and return to control values) were confirmed, although with some differences. A later return to normal of lactase was also confirmed. The same dose produced different behaviour of the enzyme activities both during the initial and the recovery phase, depending on the time of the day when irradiation was performed, i.e. on the functional condition of the epithelial cells.

  20. Zinc uptake in swine intestinal brush border membrane vesicles using a 65Zn/69mZn duel isotope experiment

    International Nuclear Information System (INIS)

    Huntington, C.E.; Morris, J.S.; Veum, T.L.

    2008-01-01

    Supplemental zinc as ZnO is routinely added to nursery pig diets at 15 to 20 times the nutritional requirement to alleviate physiological stress and enhance performance. The mechanism by which Zn accomplishes this function is unknown, however, high concentrations of Zn are excreted in the environment at undesirable levels. To study Zn uptake, we developed a multi-stage digestion model followed by exposure to swine intestinal brush border membrane vesicles (BBMV). We report on the feasibility of using a duel label ( 65 Zn and 69m Zn) to simultaneously quantify the competitive uptake of Zn from co-existing zinc supplements using our BBMV model. (author)

  1. Native proteomic analysis of protein complexes in murine intestinal brush border membranes

    Czech Academy of Sciences Publication Activity Database

    Babušiak, M.; Man, Petr; Petrák, J.; Vyoral, D.

    2007-01-01

    Roč. 7, č. 1 (2007), s. 121-129 ISSN 1615-9853 R&D Projects: GA ČR(CZ) GD204/03/H066; GA AV ČR KJB500200612; GA MŠk LC545 Grant - others:GA ČR(CZ) GA303/04/0003; GA MZd(CZ) NR8930; GA MŠk(CZ) LC06044; CZ(CZ) 023736; GA MZd(CZ) NR8317 Program:NR Institutional research plan: CEZ:AV0Z50200510 Keywords : blue native electrophoresis * brush border membranes * protein complexes Subject RIV: EE - Microbiology, Virology Impact factor: 5.479, year: 2007

  2. Galectin-2 at the enterocyte brush border of the small intestine

    DEFF Research Database (Denmark)

    Thomsen, Martha Kampp; Hansen, Gert H; Danielsen, E Michael

    2009-01-01

    boundary. Together with the membrane glycolipids these lectins form stable lipid raft microdomains that also harbour several of the major digestive microvillar enzymes. In the present work, we identified a lactose-sensitive 14-kDa protein enriched in a microvillar detergent resistant fraction as galectin-2....... Its release from closed, right-side-out microvillar membrane vesicles shows that at least some of the galectin-2 resides at the lumenal surface of the brush border, indicating that it plays a role in the organization/stabilization of the lipid raft domains. Galectin-2 was released more effectively...

  3. Kinetics of sodium D-glucose cotransport in bovine intestinal brush border vesicles.

    Science.gov (United States)

    Kaunitz, J D; Wright, E M

    1984-01-01

    Brush border membrane vesicles ( BBMV ) purified from steer jejunum were used to study the kinetics of sodium D-glucose cotransport under voltage clamped, zero-trans conditions. When the initial rate of glucose transport ( Jgluc ) was measured over a wide range of glucose concentrations ([S] = 0.01-20 mM), curvature of the Woolf - Augustinsson -Hofstee plots was seen, compatible with a diffusional and one major, high capacity (maximal transport rate Jmax = 5.8-8.8 nmol/mg X min) saturable system. Further studies indicated that changes in cis [Na] altered the Kt, but not the Jmax, suggesting the presence of a rapid-equilibrium, ordered bireactant system with sodium adding first. Trans sodium inhibited Jgluc hyperbolically, KCl-valinomycin diffusion potentials, inner membrane face positive, lowered Jgluc , while potentials of the opposite polarity raise Jgluc . At low glucose concentrations ([S] less than 0.05 mM), a second, minor, high affinity transport system was indicated. Further evidence for this second saturable system was provided by sodium activation curves, which were hyperbolic when [S] = 0.5 mM, but were sigmoidal when [S] = 0.01 mM. Simultaneous fluxes of 22Na and [3H]glucose at 1 mM glucose and 30 mM NaCl yielded a cotransport-dependent flux ratio of 2:1 sodium/glucose, suggestive of 1:1 (Na/glucose) high capacity, low affinity system and a approximately 3:1 (Na/glucose) high affinity, low capacity system. Kinetic experiments with rabbit jejunal brush borders revealed two major Na-dependent saturable systems. Extravesicular (cis) Na changed the Kt, but not the Jmax of the major system.

  4. Decreased intestinal calcium absorption in vivo and normal brush border membrane vesicle calcium uptake in cortisol-treated chickens: evidence for dissociation of calcium absorption from brush border vesicle uptake.

    OpenAIRE

    Shultz, T D; Bollman, S; Kumar, R

    1982-01-01

    The influence of cortisol on intestinal calcium transport was studied in isolated duodenal loops and brush border membrane (BBM) vesicles of vitamin D-deficient or replete chickens. Four- to five-week-old vitamin D-deficient cockerels were dosed intraperitoneally with 1 microgram of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] alone 15 hr before sacrifice or in combination with 1, 3, or 5 mg of cortisol 24 and 48 hr before sacrifice. After a 1-microgram dose of 1,25-)OH)2D3 the in situ intestinal ...

  5. Dimeric assembly of enterocyte brush border enzymes

    DEFF Research Database (Denmark)

    Danielsen, E M

    1994-01-01

    The noncovalent, dimeric assembly of small intestinal brush border enzymes was studied by sedimentation analysis in density gradients of extracts of pulse-labeled pig jejunal mucosal explants. Like aminopeptidase N (EC 3.4.11.2), sucrase-isomaltase (EC 3.2.1.48-10), aminopeptidase A (EC 3...... appearance of the liposome-reconstituted enzyme [Norén et al. (1986) J. Biol. Chem. 261, 12306-12309], showing only the inner, membrane-anchored domains of the monomers to be in close contact with one another while the outer domains are far apart. In contrast to the other brush border enzymes studied...

  6. Dietary flaxseed oil supplementation ameliorates the effect of cisplatin on brush border membrane enzymes and antioxidant system in rat intestine.

    Science.gov (United States)

    Naqshbandi, A; Rizwan, S; Khan, M W; Khan, F

    2013-04-01

    Cisplatin (CP; cis-diamminedichloroplatinum II) is a drug widely used against different types of solid tumors. Patients receiving CP, however, experience very profound and long lasting gastrointestinal symptoms. Recently, ω-3 polyunsaturated fatty acid-enriched flaxseed/flaxseed oil (FXO) has shown numerous health benefits. The present study was undertaken to investigate whether FXO can prevent CP-induced adverse biochemical changes in the small intestine of rats. A single intraperitoneal dose of CP (6 mg/kg body weight) was administered to male Wistar rats fed with control diet (CP group) and FXO diet (CPFXO group). Administration of CP led to a significant decline in the specific activities of brush border membrane enzymes both in the mucosal homogenates and in the isolated membrane vesicles. Lipid peroxidation and total sulfhydryl groups were altered upon CP treatment, indicating the generation of oxidative stress. The activities of SOD, catalase and glutathione peroxidase also decreased in CP-treated rats. In contrast, dietary supplementation of FXO prior to and following CP treatment significantly attenuated the CP-induced changes in all these parameters. FXO feeding markedly enhanced resistance to CP-elicited adverse gastrointestinal effects. The results suggest that FXO owing to its intrinsic biochemical/antioxidant properties is an effective agent in reducing the adverse effects of CP on intestine.

  7. Binding kinetics of Clostridium difficile toxins A and B to intestinal brush border membranes from infant and adult hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Rolfe, R.D. (Texas Tech Univ. Health Sciences Center, Lubbock (USA))

    1991-04-01

    This study was undertaken to determine if the relative resistance of neonates and infants to Clostridium difficile-associated intestinal disease can be related to age-dependent differences in intestinal receptors for C. difficile toxins A and B. Brush border membranes (BBMs) from the small intestines of adult and infant hamsters were examined for their ability to bind radiolabeled toxins A and B. (125I)toxin A bound to both infant and adult hamster BBMs at physiological temperature, whereas (125I)toxin B did not bind to the BBMs under any of the conditions examined. The number of (125I)toxin A molecules bound at saturation was approximately 4 x 10(10) per micrograms of membrane protein for adult BBMs and 1 x 10(11) per micrograms of membrane protein for infant BBMs. Scatchard plot analysis suggested the presence of a single class of toxin A binding sites on both infant and adult hamster BBMs. Maximal binding capacity and Kd values were 0.63 pmol/mg of protein and 66.7 nM, respectively, for the infant BBMs, and 0.24 pmol/mg of protein and 27 nM, respectively, for the adult BBMs. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic analyses of extracted BBM proteins revealed differences in the proteins of infant and adult BBMs. However, there were not any detectable differences in the protein bands which bound (125I)toxin A between infant and adult hamsters. The results from these investigations indicate that differences in the binding kinetics of toxins A and/or B to infant and adult hamster BBMs do not account for the observed differences in their susceptibility to C. difficile-associated intestinal disease.

  8. Intestinal alkaline phosphatase: selective endocytosis from the enterocyte brush border during fat absorption

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Niels-Christiansen, Lise-Lotte; Immerdal, Lissi

    2007-01-01

    Absorption of dietary fat in the small intestine is accompanied by a rise of intestinal alkaline phosphatase (IAP) in the serum and of secretion of IAP-containing surfactant-like particles from the enterocytes. In the present work, fat absorption was studied in organ cultured mouse intestinal exp...

  9. A kinetic study of the interactions between amino acids and monosaccharides at the intestinal brush-border membrane.

    Science.gov (United States)

    Alvarado, F; Robinson, J W

    1979-10-01

    1. The influx of amino acids into guinea-pig intestinal rings in vitro is inhibited by monosaccharides, and that of monosaccharides by amino acids. Two hypotheses have been proposed to account for these heterologous interactions. According to the first, the cis hypothesis, there is an allosteric interaction between substrates binding to separate but related sites at the outer face of the brush-border membrane matrix. In contrast, the trans hypothesis envisages the interaction to result from a partial dissipation of the electrochemical sodium gradient due to the cotransport of each substrate with sodium ions. 2. In an attempt to distinguish between the merits of the two hypotheses, we examined the kinetics of the inhibition of phenylalanine influx by two sugars of widely different affinities, galactose and beta-methylglucoside. Since beta-methylglucoside carries more sodium into the cell than galactose, the trans hypothesis would predict it to be the stronger inhibitor, but in fact the opposite result is found. 3. Equations were developed to describe the inhibitions in accordance with the cis hypothesis. The satisfactory agreement between experimental observations and theoretical predictions provides support for the applicability of the model. Further implications of the polyfunctional carrier model are discussed.

  10. Comparison of two pig intestinal brush border peptidases with the corresponding renal enzymes

    DEFF Research Database (Denmark)

    Norén, O; Sjöström, H; Danielsen, Erik Michael

    1979-01-01

    Intestinal dipeptidyl peptidase IV and gamma-glutamyltransferase were compared to the corresponding kidney enzymes with respect to immunological and electrophoretic properties. The influences of selected effectors on the two enzymes were also studied. The two kidney peptidases exhibited...... the reaction of total identity with the corresponding intestinal enzymes in immunodiffusion. Furthermore, the intestinal dipeptidyl peptidase IV and gamma-glutamyl transferase showed the same inhibition patterns as the corresponding kidney enzymes and the acceptor specificity of the intestinal gamma......-glutamyl-transferase was found to be identical to that of the kidney enzyme. The electrophoretic mobilities of dipeptidyl peptidase IV from the two organs differed greatly. The difference was almost abolished by treatment with neuraminidase, suggesting that the variation in mobility was due to different contents of sialic acid...

  11. Effect of fluoride on the intestinal epithelial cell brush border membrane

    Energy Technology Data Exchange (ETDEWEB)

    Rastogi, R.; Upreti, R.K.; Kidwai, A.M.

    1987-07-01

    Fluoride consumed by man and animals is chiefly absorbed in the intestine. Chronic fluoride exposure causes mottled teeth and osteosclerosis. Over-fluoridation (126 mM) of drinking water have been reported to cause nausea, vomiting and diarrhea. Furthermore, the effect of acute and low concentrations of fluoride on gastric secretion, ion transport and other disorders have also been studied. Fluoride also causes alterations in the permeability of membranes and membrane bound enzymes. The intestinal cell lining plays an important role in digestion and absorption. It automatically becomes the most exposed site of contact to fluoride following ingestion. Earlier study have shown significant alterations in the formation of lipid peroxides in rat intestine following oral administration of fluoride. The present study was undertaken to investigate the damage of rat intestinal epithelium in situ caused by relatively high and low fluoride concentrations.

  12. Intestinal microbiota differentially affect brush border enzyme activity and gene expression in the neonatal gnotobiotic pig.

    Science.gov (United States)

    Willing, B P; Van Kessel, A G

    2009-10-01

    To study microbial influence on intestinal development pertaining to nutrient digestion, two separate gnotobiotic experiments were performed, each with 16 piglets allocated to four treatment groups: germfree (GF), monoassociation with Escherichia coli, monoassociation with Lactobacillus fermentum or conventionalization with faecal bacteria (CV). Enzyme activity and gene expression of lactase phlorizin hydrolase (LPH) and aminopeptidase N (APN) were measured in isolated enterocytes, harvested on day 14, using specific substrates and quantitative PCR respectively. Enterocytes of CV pigs had reduced APN activity, but had increased gene expression relative to GF, making the specific activity:mRNA (A:G) ratio dramatically lower (p pigs as compared with GF. The results of co-incubation of L. fermentum, E. coli and faecal bacteria with APN indicate a direct relationship between enzyme inactivation and specific A:G ratio in enterocytes. We conclude that enterocyte up-regulation of APN expression occurs as either a direct response to microbial colonization or as a feedback mechanism in response to reduced enzyme activity through microbial degradation. This mechanism may play a role in ensuring effective competition of the host with the intestinal microbiota for available nutrients.

  13. Decreased intestinal calcium absorption in vivo and normal brush border membrane vesicle calcium uptake in cortisol-treated chickens: evidence for dissociation of calcium absorption from brush border vesicle uptake.

    Science.gov (United States)

    Shultz, T D; Bollman, S; Kumar, R

    1982-06-01

    The influence of cortisol on intestinal calcium transport was studied in isolated duodenal loops and brush border membrane (BBM) vesicles of vitamin D-deficient or replete chickens. Four- to five-week-old vitamin D-deficient cockerels were dosed intraperitoneally with 1 microgram of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] alone 15 hr before sacrifice or in combination with 1, 3, or 5 mg of cortisol 24 and 48 hr before sacrifice. After a 1-microgram dose of 1,25-)OH)2D3 the in situ intestinal ligated loop technique revealed a 60% increase in calcium absorption compared to control birds (P less than or equal to 0.001). However, the administration of cortisol in various doses (3 and 5 mg) to chickens given 1,25-(OH)2D3 resulted in significant decreases in intestinal calcium transport in vivo (P less than or equal to 0.05; P less than or equal to 0.05). When intestinal BBM vesicles were prepared from birds treated in a manner identical with that described above, there was no observable difference between calcium uptake in BBM vesicles of the 1,25-(OH)2D3-treated birds and that of the cortisol plus 1,25-(OH)2D3-treated birds. 1,25-(OH)2D3-treated and 1,25-(OH)2D3 plus cortisol-treated chicks had intestinal BBM vesicle uptakes that were significantly greater than those of vitamin D-deficient controls (P less than or equal to 0.02; P less than or equal to 0.025). These data show that in vivo intestinal calcium transport may be markedly reduced in the presence of normal intestinal BBM vesicle calcium uptake. This suggest that factors other than BBM calcium uptake (e.g., protein synthesis or contraluminal membrane events) play an important role in the movement of calcium from the intestinal lumen into the bloodstream and extracellular fluid of the organism.

  14. (Na+ + K+)-ATPase and plasma membrane polarity of intestinal epithelial cells: Presence of a brush border antigen in the distal large intestine that is immunologically related to beta subunit

    Energy Technology Data Exchange (ETDEWEB)

    Marxer, A.; Stieger, B.; Quaroni, A.; Kashgarian, M.; Hauri, H.P. (Univ. of Basel (Switzerland))

    1989-09-01

    The previously produced monoclonal antibody IEC 1/48 against cultured rat intestinal crypt cells was extensively characterized and found to be directed against the beta subunit of (Na+ + K+)-ATPase as assessed by immunological and enzymatic criteria. Under nondenaturing conditions the antibody precipitated the alpha-beta enzyme complex (98,000 and 48,000 Mr). This probe, together with the monoclonal antibody C 62.4 against the alpha subunit was used to localize (Na+ + K+)-ATPase in epithelial cells along the rat intestinal tract by immunofluorescence and immunoelectron microscopy. Both antibodies exclusively labeled the basolateral membrane of small intestine and proximal colon epithelial cells. However, in the distal colon, IEC 1/48, but not C 62.4, also labeled the brush border membrane. The cross-reacting beta-subunit-like antigen on the apical cell pole was tightly associated with isolated brush borders but was apparently devoid of (Na+ + K+)-ATPase activity. Subcellular fractionation of colonocytes in conjunction with limited proteolysis and surface radioiodination of intestinal segments suggested that the cross-reacting antigen in the brush border may be very similar to the beta subunit. The results support the notion that in the small intestine and proximal colon the enzyme subunits are exclusively targeted to the basolateral membrane while in the distal colon nonassembled beta subunit or a beta-subunit-like protein is also transported to the apical cell pole.

  15. Folding of intestinal brush border enzymes. Evidence that high-mannose glycosylation is an essential early event

    DEFF Research Database (Denmark)

    Danielsen, E M

    1992-01-01

    a posttranslational process. In the presence of fructose, not only the malglycosylated forms but also the electrophoretically normal, high-mannose-glycosylated form of the brush border enzymes were retained in the endoplasmic reticulum and proteolytically degraded. The results obtained demonstrate an intimate...... enzymes. In pulse-labeled mucosal explants, complete synthesis of the polypeptide chains of aminopeptidase N and sucrase-isomaltase required about 2 and 4 min, respectively, whereas maximal antiserum precipitation was acquired with half-times of 4-5 and 8 min, respectively. Fructose, which induces...

  16. Oral administration of thymoquinone mitigates the effect of cisplatin on brush border membrane enzymes, energy metabolism and antioxidant system in rat intestine.

    Science.gov (United States)

    Shahid, Faaiza; Farooqui, Zeba; Abidi, Subuhi; Parwez, Iqbal; Khan, Farah

    2017-10-01

    Cisplatin (CP) is a widely used chemotherapeutic agent that elicits severe gastrointestinal toxicity. Nigella sativa, a member of family Ranunculaceae, is one of the most revered medicinal plant known for its numerous health benefits. Thymoquinone (TQ), a major bioactive component derived from the volatile oil of Nigella sativa seeds, has been shown to improve gastrointestinal functions in animal models of acute gastric/intestinal injury. In view of this, the aim of the present study was to investigate the protective effect of TQ on CP induced toxicity in rat intestine and to elucidate the mechanism underlying these effects. Rats were divided into four groups viz. control, CP, TQ and CP+TQ. Animals in CP+TQ and TQ groups were orally administered TQ (1.5mg/kg bwt) with and without a single intraperitoneal dose of CP (6mg/kg bwt) respectively. The effect of TQ was determined on CP induced alterations in the activities of brush border membrane (BBM), carbohydrate metabolism, and antioxidant defense enzymes in rat intestine. TQ administration significantly mitigated CP induced decline in the specific activities of BBM marker enzymes, both in the mucosal homogenates and in the BBM vesicles (BBMV) prepared from intestinal mucosa. Furthermore, TQ administration restored the redox and metabolic status of intestinal mucosal tissue in CP treated rats. The biochemical results were supported by histopathological findings that showed extensive damage to intestine in CP treated rats and markedly preserved intestinal histoarchitecture in CP and TQ co-treated group. The biochemical and histological data suggest a protective effect of TQ against CP-induced gastrointestinal damage. Thus, TQ may have a potential for clinical application to counteract the accompanying gastrointestinal toxicity in CP chemotherapy. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  17. Oral administration of caffeic acid ameliorates the effect of cisplatin on brush border membrane enzymes and antioxidant system in rat intestine.

    Science.gov (United States)

    Arivarasu, N A; Priyamvada, Shubha; Mahmood, Riaz

    2013-01-01

    Cisplatin (CP) is a widely used antineoplastic drug that exhibits gastrointestinal toxicity. We have previously shown that administration of a single dose of CP results in a decrease in the activities of several brush border membrane (BBM) enzymes, induces oxidative stress and alters the activities of several antioxidant enzymes in the small intestine of rats. In the present study we have investigated the effect of treatment with the dietary antioxidant caffeic acid (CA) on CP induced biochemical changes in the intestine. Administration of a single intraperitoneal dose of CP alone (6 mg/kg body weight) led to a decrease in the activities of the BBM enzymes, increase in lipid peroxidation, decrease in sulfhydryl groups and changes in the activities of catalase, superoxide dismutase, glutathione peroxidase, glucose 6-phosphate dehydrogenase, glutathione reductase, glutathione S-transferase and thioredoxin reductase. Administration of two doses of CA (each of 250 mg/kg body weight), at 15 and 120 min after treatment with CP, significantly attenuated the CP-induced changes in all these parameters but the administration of CA alone had no effect. These results suggest that CA is an effective agent in reducing the effects of CP on the intestine and could prove to be useful in alleviating the gastrointestinal toxicity of this drug. Copyright © 2011 Elsevier GmbH. All rights reserved.

  18. Sodium chlorate, a major water disinfection byproduct, alters brush border membrane enzymes, carbohydrate metabolism and impairs antioxidant system of Wistar rat intestine.

    Science.gov (United States)

    Ali, Shaikh Nisar; Ansari, Fariheen Aisha; Khan, Aijaz Ahmed; Mahmood, Riaz

    2017-05-01

    Sodium chlorate (NaClO 3 ) is a widely used nonselective herbicide. It is also generated as a by-product during disinfection of drinking water by chlorine dioxide. The purpose of this study was to evaluate the effect of NaClO 3 on rat intestine. Adult male rats were randomly divided into five groups: control and remaining four groups were administered orally different doses of NaClO 3 and sacrificed 24 h after the treatment. The administration of NaClO 3 produced acute oxidative stress in the intestine, which manifested in the form of markedly enhanced malondialdehyde levels and carbonyl content and lowered total sulfhydryl groups and glutathione levels. The activities of several brush border membrane (BBM) enzymes were greatly reduced as compared to control. There were alterations in the activities of various enzymes of carbohydrate metabolism and those involved in maintaining the antioxidant defense system. Histological studies support the biochemical results showing NaClO 3 dose-dependent increase in tissue damage. Thus, the present study shows that oral administration of NaClO 3 decreases the activities of BBM enzymes, induces oxidative stress, alters metabolic pathways, and impairs the antioxidant system of rat intestine. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1607-1616, 2017. © 2017 Wiley Periodicals, Inc.

  19. Oral administration of Nigella sativa oil ameliorates the effect of cisplatin on brush border membrane enzymes, carbohydrate metabolism and antioxidant system in rat intestine.

    Science.gov (United States)

    Shahid, Faaiza; Farooqui, Zeba; Rizwan, Sana; Abidi, Subuhi; Parwez, Iqbal; Khan, Farah

    2017-06-14

    Cisplatin (CP) is an effective chemotherapeutic agent that induces gastrointestinal toxicity. Nigella sativa oil (NSO) has been shown to be beneficial in a wide range of gastrointestinal disorders. The present study investigates the possible protective effect of NSO on CP-induced gastrointestinal toxicity. NSO administration (2ml/kg bwt, orally), prior to and following, a single dose CP treatment (6mg/kg bwt. ip), significantly attenuated the CP-induced decrease in brush border membrane (BBM) enzyme activities in intestinal homogenates and BBM vesicles (BBMV). NSO administration also mitigated CP induced alterations in the activities of carbohydrate metabolism enzymes and in the enzymatic and non-enzymatic antioxidant parameters in the intestine. The results suggest that NSO by empowering the endogenous antioxidant system improves intestinal redox and metabolic status and restores BBM integrity in CP treated rats. Histopathological studies supported the biochemical findings. Thus, NSO may help prevent the accompanying gastrointestinal dysfunction in CP chemotherapy. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. Binding of Transmissible Gastroenteritis Coronavirus to Brush Border Membrane Sialoglycoproteins

    OpenAIRE

    Schwegmann-Wessels, Christel; Zimmer, Gert; Schröder, Bernd; Breves, Gerhard; Herrler, Georg

    2003-01-01

    Transmissible gastroenteritis coronavirus (TGEV) is a porcine pathogen causing enteric infections that are lethal for suckling piglets. The enterotropism of TGEV is connected with the sialic acid binding activity of the viral surface protein S. Here we show that, among porcine intestinal brush border membrane proteins, TGEV recognizes a mucin-type glycoprotein designated MGP in a sialic acid-dependent fashion. Virus binding assays with cryosections of the small intestine from a suckling pigle...

  1. Dietary cholesterol induces trafficking of intestinal Niemann-Pick Type C1 Like 1 from the brush border to endosomes

    DEFF Research Database (Denmark)

    Skov, Marianne; Tønnesen, Carina K; Hansen, Gert H

    2011-01-01

    The transmembrane protein Niemann-Pick C1 Like 1 (NPC1L1) belongs to the Niemann-Pick C1 (NPC1) family of cholesterol transporters and is mainly expressed in the liver and the small intestine. NPC1L1 is believed to be the main transporter responsible for the absorption of dietary cholesterol. Lik...

  2. Effect of nonpathogenic Escherichia coli monoassociation on small intestinal brush-border glycoconjugate moieties and cytokine production after colonization in ex-germ-free rats and pigs

    Czech Academy of Sciences Publication Activity Database

    Kolínská, Jiřina; Zákostelecká, Marie; Schwarzer, Martin; Štěpánková, Renata; Hudcovic, Tomáš; Kozáková, Hana

    2010-01-01

    Roč. 2, - (2010), s. 73-84 ISSN 1179-139X R&D Projects: GA MŠk(CZ) ME10017 Grant - others:GA AV ČR(CZ) IAA500200710; GA ČR(CZ) GA303/09/0449 Program:IA; GA Institutional research plan: CEZ:AV0Z50110509; CEZ:AV0Z50200510 Keywords : nonpathogenic E. coli * glycoconjugates * brush-border vesicles Subject RIV: CE - Biochemistry

  3. Probing endocytosis from the enterocyte brush border using fluorescent lipophilic dyes

    DEFF Research Database (Denmark)

    Danielsen, E Michael

    2015-01-01

    The small intestinal brush border is a specialized cell membrane that needs to withstand the solubilizing effect of bile salts during assimilation of dietary nutrients and to achieve detergent resistance; it is highly enriched in glycolipids organized in lipid raft microdomains. In the present work......-toluenesulfonate), and CellMask Orange plasma membrane stain were used to study endocytosis from the enterocyte brush border of organ-cultured porcine mucosal explants. All the dyes readily incorporated into the brush border but were not detectably endocytosed by 5 min, indicating a slow uptake compared with other cell types...

  4. Lipid rafts in epithelial brush borders: atypical membrane microdomains with specialized functions

    DEFF Research Database (Denmark)

    Danielsen, E Michael; Hansen, Gert H

    2003-01-01

    Epithelial cells that fulfil high-throughput digestive/absorptive functions, such as small intestinal enterocytes and kidney proximal tubule cells, are endowed with a dense apical brush border. It has long been recognized that the microvillar surface of the brush border is organized in cholesterol......-dependent lipid rafts of a different type from the glycolipid-based rafts at the microvillar surface. The brush border is thus an example of a complex membrane system that harbours at least two different types of lipid raft microdomains, each suited to fulfil specialized functions. This conclusion is in line......-linked and transmembrane digestive enzymes, most likely as an economizing effort to secure and prolong their digestive capability at the microvillar surface. However, in addition to microvilli, the brush border surface also consists of membrane invaginations between adjacent microvilli, which are the only part...

  5. Oral Nigella sativa oil and thymoquinone administration ameliorates the effect of long-term cisplatin treatment on the enzymes of carbohydrate metabolism, brush border membrane, and antioxidant defense in rat intestine.

    Science.gov (United States)

    Shahid, Faaiza; Farooqui, Zeba; Khan, Aijaz Ahmed; Khan, Farah

    2018-02-01

    We have previously shown that oral administration of Nigella sativa oil (NSO) ameliorates the deleterious gastrointestinal effects of cisplatin (CP), administered as a single dose. Since a typical clinical CP dosing regimen involves multiple cycles of CP administration in lower doses, in the present study we investigate the protective efficacy of NSO and its major bioactive constituent, thymoquinone (TQ), against multiple-dose CP treatment-induced deleterious biochemical and histological changes in rat intestine. Rats were divided into six groups, viz., control, CP, CP+NSO, CP+TQ, NSO, and TQ. Animals in CP+NSO and CP+TQ groups were pre-administered NSO (2 ml/kg bwt, orally) and TQ (1.5 mg/kg bwt, orally), respectively, daily for 14 days and were then treated with five repeated doses of CP (3 mg/kg bwt, i.p.), every fourth day for 20 days while still receiving NSO/TQ. CP treatment alone led to a significant decline in specific activities of brush border membrane (BBM) enzymes while NSO or TQ administration to CP-treated rats significantly prevented the decline in BBM enzyme activities in the isolated brush border membrane vesicles (BBMV) as well as in mucosal homogenates. Furthermore, both NSO and TQ administration markedly ameliorated CP-induced alterations on carbohydrate metabolism enzymes and the enzymatic and non-enzymatic parameters of antioxidant defense system in the intestinal mucosa. However, NSO appeared to be more efficacious than TQ in protecting against CP-induced gastrointestinal dysfunction. Histopathological findings corroborated the biochemical results. Thus, NSO and TQ may prove clinically useful in amelioration of the intestinal toxicity associated with long-term CP chemotherapy.

  6. Studies on the mechanism of cholesterol uptake and on the effects of bile salts on this uptake by brush-border membranes isolated from rabbit small intestine.

    Science.gov (United States)

    Proulx, P; Aubry, H; Brglez, I; Williamson, D G

    1984-12-19

    The effect of bile salts and other surfactants on the rate of incorporation of cholesterol into isolated brush-border membranes was tested. At constant cholesterol concentration, a stimulatory effect of taurocholate was noticed which increased as the bile salt concentration was raised to 20 mM. Taurodeoxycholate was as effective as taurocholate at concentrations of up to 5 mM and inhibited at higher concentrations. Glycocholate was only moderately stimulatory whereas cholate was nearly as effective as taurocholate at concentrations above 5 mM. Other surfactants such as sodium lauryl sulfate and Triton X-100 were very inhibitory at all concentrations tried whereas cetyltrimethyl ammonium chloride was stimulatory only at a very low range of concentrations. These micellizing agents all caused some disruption of the membranes and the greater effectiveness of taurocholate in stimulating sterol uptake was partly relatable to the weaker membrane solubilizing action of this bile salt. Preincubation of membranes with 20 mM taurocholate followed by washing and exposure to cholesterol-containing lipid suspensions lacking bile salt, did not enhance the incorporation of the sterol. In the absence of bile salt the incorporation of cholesterol was unaffected by stirring of the incubation mixtures. Increasing the cholesterol concentration in the mixed micelle while keeping the concentration of bile salt constant caused an increase in rate of sterol incorporation. This increased rate was seen whether the cholesterol suspension was turbid, i.e., contained non-micellized cholesterol, or whether it was optically-clear and contained only monomers and micelles. When the concentration of taurocholate and cholesterol were increased simultaneously such that the concentration ratio of these two components was kept constant, there resulted a corresponding increase in rate of cholesterol uptake. The initial rates of cholesterol incorporation from suspensions containing micellar and monomer

  7. Brush border myosin Ia inactivation in gastric but not endometrial tumors

    NARCIS (Netherlands)

    Mazzolini, Rocco; Rodrigues, Paulo; Bazzocco, Sarah; Dopeso, Higinio; Ferreira, Ana M.; Mateo-Lozano, Silvia; Andretta, Elena; Woerner, Stefan M.; Alazzouzi, Hafid; Landolfi, Stefania; Hernandez-Losa, Javier; Macaya, Irati; Suzuki, Hiromu; Ramon y Cajal, Santiago; Mooseker, Mark S.; Mariadason, John M.; Gebert, Johannes; Hofstra, Robert M. W.; Reventos, Jaume; Yamamoto, Hiroyuki; Schwartz, Simo; Arango, Diego

    2013-01-01

    Brush border Myosin Ia (MYO1A) has been shown to be frequently mutated in colorectal tumors with microsatellite instability (MSI) and to have tumor suppressor activity in intestinal tumors. Here, we investigated the frequency of frameshift mutations in the A8 microsatellite in exon 28 of MYO1A in

  8. Identification of sugar residues involved in the binding of TGEV to porcine brush border membranes.

    Science.gov (United States)

    Schwegmann-Wessels, Christel; Herrler, Georg

    2008-01-01

    Coronaviruses most often infect the respiratory or intestinal tract. Transmissible gastroenteritis virus (TGEV), a group 1 coronavirus, infects the porcine small intestine. Piglets up to the age of 3 weeks die from diarrhea caused by the viral gastroenteritis unless they are protected by antibodies. In addition to the cellular receptor, porcine aminopeptidase N, the TGEV spike protein binds to sialic acid residues. We have shown that the sialic acid binding activity mediates the binding of TGEV to a mucin-like glycoprotein present in porcine brush border membranes. This was shown by performing a virus overlay binding assay with proteins obtained from brush border membranes by lectin precipitation. Because of the reactivity with specific lectins we assume that the recognized glycoprotein has the characteristics of a mucin.

  9. Library of monoclonal antibodies against brush border membrane epithelial antigens

    International Nuclear Information System (INIS)

    Behar, M.; Katz, A.; Silverman, M.

    1986-01-01

    A purified fraction of proximal tubule brush border membranes (BBM) was prepared from dog kidney and used to immunize mice. The standard technique of hybridoma production was followed as described by Kohler and Milstein. Production of antibodies was detected by indirect immunofluorescence on dog kidney slices and by immunodot against the purified fraction on nitrocellulose. Five hybrids exhibited anti BBM activity. These were cloned twice and yielded stable cell lines producing IgG type monoclonal antibodies against BBM. They were designated A 1 , C 7 , D 3 , D 7 and H 4 . As a family these five monoclonals have broad tissue specificity, i.e. positive staining of the surface mucosa of intestinal kidney proximal tubules. D 3 exhibits even broader specificity for epithelium reacting with bile canaliculi and choroid plexus. The authors have verified that at least 4/5 antibodies are directed against BBM protein as revealed by immunoprecipitation of solubilized BBM and detected by Coomassie blue staining or autoradiography of lactoperoxidase labelled BBM. Most interestingly all antibodies bind to the surface of LL CPK 1 cells, a continuous pig kidney cell line of undefined origin but exhibiting many characteristics of proximal tubule cells. The library of monoclonal antibodies obtained provide important probes with which to study membrane biogenesis and polarization in epithelial cells

  10. Faecal excretion of brush border membrane enzymes in patients with clostridium difficile diarrhoea

    Directory of Open Access Journals (Sweden)

    Katyal R

    2002-01-01

    Full Text Available PURPOSE: To look for the presence of intestinal brush border membrane (BBM enzymes in the faecal samples of patients with Clostridium difficile association. METHODS: One hundred faecal samples were investigated for C.difficile toxin (CDT. Simultaneous assays for faecal excretion of intestinal BBM enzymes viz., disaccharidases, alkaline phosphatase (AP and leucine aminopeptidase (LAP were also done. RESULTS: C.difficile toxin was detected in 25 (25% of the samples with a titre ranging from 10 to 160. No significant difference (p>0.05 was seen between the CDT positive and negative groups with any of the disaccharidases studied. However, significant increase (pC.difficile diarrhoea.

  11. Effects of dietary copper on growth, digestive, and brush border enzyme activities and antioxidant defense of hepatopancreas and intestine for young grass carp (Ctenopharyngodon idella).

    Science.gov (United States)

    Tang, Q Q; Feng, L; Jiang, W D; Liu, Y; Jiang, J; Li, S H; Kuang, S Y; Tang, L; Zhou, X Q

    2013-12-01

    To investigate the effects of dietary copper (Cu) on fish growth, digestive and absorptive enzyme activities, and antioxidant status in the hepatopancreas and intestine, young grass carp (Ctenopharyngodon idella) (282±2.8 g) were fed six diets containing 0.74 (basal diet), 2.26, 3.75, 5.25, 6.70, and 8.33 mg Cu /kg diet for 8 weeks. Results showed that percentage weight gain (PWG) and feed intake were increased with dietary Cu levels up to 3.75 mg/kg diet. In addition, the positive effects of dietary Cu at a level 3.75 or 5.25 mg/kg diet on trypsin, chymotrypsin, and lipase activities in the hepatopancreas and of Na(+), K(+)-ATPase, alkaline phosphatase, creatine kinase, and γ-glutamyl transpeptidase activities in three intestine segments produced significantly (Pdietary Cu levels up to 3.75 mg/kg diet (Pdietary Cu at 3.75 or 5.25 mg/kg diet decreased malondialdehyde and protein carbonyl content partly by significantly (Pdietary Cu improved growth and digestive and absorptive capacity and decreased lipid peroxidation and protein oxidation partly by enhancing antioxidant defense in the hepatopancreas and intestine. The dietary Cu requirement for PWG, plasma ceruloplasmin activity, and FE of young grass carp (282-688 g) were 4.78, 4.95, and 4.70 mg/kg diet, respectively.

  12. Effect of dietary crude protein level on jejunal brush border enzyme activities in weaned pigs.

    Science.gov (United States)

    Opapeju, Florence Omobola; Rademacher, Meike; Nyachoti, Charles Martin

    2009-01-01

    Forty weaned pigs (7.0 ± 0.5 kg, mean ± SD) were used to determine the effects of feeding a low crude protein, amino acid-supplemented diet to piglets on the activities of jejunal brush border enzymes. Pigs were randomly allotted to two diets: a 222 g crude protein (HCP) per kg diet, or a 173 g crude protein per kg diet supplemented with amino acids (LCP). Pigs fed the HCP diet had higher small intestine weight compared with those fed the LCP diet on day 7 after weaning. Diet had no effect on the specific activities of jejunal sucrase, lactase, leucine aminopeptidase, aminopeptidase A, aminopeptidase N and dipeptidyl peptidase IV. The activities of sucrase and lactase decreased (p effect on the development of jejunal brush border enzymes.

  13. Alterations in the proteome of the NHERF1 knockout mouse jejunal brush border membrane vesicles

    OpenAIRE

    Donowitz, M.; Singh, S.; Singh, P.; Salahuddin, F. F.; Chen, Y.; Chakraborty, M.; Murtazina, R.; Gucek, M.; Cole, R. N.; Zachos, N. C.; Kovbasnjuk, O.; Broere, N.; Smalley-Freed, W. G.; Reynolds, A. B.; Hubbard, A. L.

    2010-01-01

    Na/H exchanger regulatory factor 1 (NHERF1) is a scaffold protein made up of two PDZ domains and an ERM binding domain. It is in the brush border of multiple epithelial cells where it modulates 1) Na absorption by regulating NHE3 complexes and cytoskeletal association, 2) Cl secretion through trafficking of CFTR, and 3) Na-coupled phosphate absorption through membrane retention of NaPi2a. To further understand the role of NHERF1 in regulation of small intestinal Na absorptive cell function, w...

  14. Alterations in the proteome of the NHERF1 knockout mouse jejunal brush border membrane vesicles.

    Science.gov (United States)

    Donowitz, M; Singh, S; Singh, P; Salahuddin, F F; Chen, Y; Chakraborty, M; Murtazina, R; Gucek, M; Cole, R N; Zachos, N C; Kovbasnjuk, O; Broere, N; Smalley-Freed, W G; Reynolds, A B; Hubbard, A L; Seidler, U; Weinman, E; de Jonge, H R; Hogema, B M; Li, X

    2010-11-15

    Na/H exchanger regulatory factor 1 (NHERF1) is a scaffold protein made up of two PDZ domains and an ERM binding domain. It is in the brush border of multiple epithelial cells where it modulates 1) Na absorption by regulating NHE3 complexes and cytoskeletal association, 2) Cl secretion through trafficking of CFTR, and 3) Na-coupled phosphate absorption through membrane retention of NaPi2a. To further understand the role of NHERF1 in regulation of small intestinal Na absorptive cell function, with emphasis on apical membrane transport regulation, quantitative proteomic analysis was performed on brush border membrane vesicles (BBMV) prepared from wild-type (WT) and homozygous NHERF1 knockout mouse jejunal villus Na absorptive cells. Jejunal architecture appeared normal in NHERF1 null; however, there was increased proliferative activity, as indicated by increased crypt BrdU staining. LC-MS/MS analysis using iTRAQ to compare WT and NHERF1 null BBMV identified 463 proteins present in both WT and NHERF1 null BBMV of simultaneously prepared and studied samples. Seventeen proteins had an altered amount of expression between WT and NHERF1 null in two or more separate preparations, and 149 total proteins were altered in at least one BBMV preparation. The classes of the majority of proteins altered included transport proteins, signaling and trafficking proteins, and proteins involved in proliferation and cell division. Affected proteins also included tight junction and adherens junction proteins, cytoskeletal proteins, as well as metabolic and BB digestive enzymes. Changes in abundance of several proteins were confirmed by immunoblotting [increased CEACAM1, decreased ezrin (p-ezrin), NHERF3, PLCβ3, E-cadherin, p120, β-catenin]. The changes in the jejunal BBMV proteome of NHERF1 null mice are consistent with a more complex role of NHERF1 than just forming signaling complexes and anchoring proteins to the apical membrane and include at least alterations in proteins involved in

  15. The cell adhesion molecule Fasciclin2 regulates brush border length and organization in Drosophila renal tubules.

    Science.gov (United States)

    Halberg, Kenneth A; Rainey, Stephanie M; Veland, Iben R; Neuert, Helen; Dornan, Anthony J; Klämbt, Christian; Davies, Shireen-Anne; Dow, Julian A T

    2016-04-13

    Multicellular organisms rely on cell adhesion molecules to coordinate cell-cell interactions, and to provide navigational cues during tissue formation. In Drosophila, Fasciclin 2 (Fas2) has been intensively studied due to its role in nervous system development and maintenance; yet, Fas2 is most abundantly expressed in the adult renal (Malpighian) tubule rather than in neuronal tissues. The role Fas2 serves in this epithelium is unknown. Here we show that Fas2 is essential to brush border maintenance in renal tubules of Drosophila. Fas2 is dynamically expressed during tubule morphogenesis, localizing to the brush border whenever the tissue is transport competent. Genetic manipulations of Fas2 expression levels impact on both microvilli length and organization, which in turn dramatically affect stimulated rates of fluid secretion by the tissue. Consequently, we demonstrate a radically different role for this well-known cell adhesion molecule, and propose that Fas2-mediated intermicrovillar homophilic adhesion complexes help stabilize the brush border.

  16. Anti-glycosyl antibodies in lipid rafts of the enterocyte brush border: a possible host defense against pathogens

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Pedersen, Esben D K; Immerdal, Lissi

    2005-01-01

    a major part of the immunoglobulins at the lumenal surface of the gut. The antibodies were associated with lipid rafts at the brush border, and they frequently (52%) coclustered with the raft marker galectin 4. A lactose wash increased the susceptibility of the brush border toward lectin peanut agglutin...

  17. The cell adhesion molecule Fasciclin2 regulates brush border length and organization in Drosophila renal tubules

    DEFF Research Database (Denmark)

    Halberg, Kenneth Agerlin; Rainey, Stephanie M.; Veland, Iben Rønn

    2016-01-01

    abundantly expressed in the adult renal (Malpighian) tubule rather than in neuronal tissues. The role Fas2 serves in this epithelium is unknown. Here we show that Fas2 is essential to brush border maintenance in renal tubules of Drosophila. Fas2 is dynamically expressed during tubule morphogenesis...

  18. Acid/base transport in a model of the proximal tubule brush border: impact of carbonic anhydrase.

    Science.gov (United States)

    Krahn, T A; Weinstein, A M

    1996-02-01

    A mathematical model of the brush border of the proximal tubule (T. A. Krahn, P. S. Aronson, and A. M. Weinstein. Bull. Math. Biol, 56: 459-490, 1994) has been extended by the inclusion of CO2 and H2CO3 as diffusible species and by the inclusion of finite rate constants for the hydration of CO2. This permits the simulation of carbonic anhydrase (CA) activity and its inhibition. We confirm the result of our previous study, which is that, in the presence of CA, the unstirred layer has only a modest effect on the observed formic acid permeability. CA inhibition results in disequilibrium pH gradients, and the effect of these gradients on formic acid permeability depends on the presence of other membrane transport proteins. We also examined the impact of CA activity on the flux of total CO2 through the brush border. Under physiological conditions, CA inhibition depressed NaHCO3 reabsorption through the brush border by interfering with the HCO3(-)-facilitated diffusion of CO2. However, the determination of brush-border CO2 permeability, using an imposed CO2 gradient, was relatively uninfluenced by CA activity. Finally, we inserted a kinetic representation of the Na+/H+ exchanger into the brush-border model. Even when luminal and cytosolic diffusion coefficients were increased 1,000-fold, there was no effect on brush-border Na+ flux. This suggests that variations in the unstirred layer cannot be responsible for the flow dependence of Na+ reabsorption.

  19. Orientation of the brush-border membranal proteinase which specifically splits the catalytic subunit of cAMP-dependent protein kinase.

    Science.gov (United States)

    De Jonge, H; Schmeeda, H; Shaltiel, S

    1987-12-15

    The active site of the rat intestinal brush-border membranal proteinase [Alhanaty E. and Shaltiel S. (1979) Biochem. Biophys. Res. Commun. 89, 323-332], which splits the catalytic subunit (C) of cAMP-dependent protein kinase with a remarkable specificity [Alhanaty E., Tauber-Finkelstein, M., Schmeeda, H. and Shaltiel, S. (1985) Curr. Topics Cell. Regul. 27, 267-277], is shown to face predominantly the cell exterior; vesicles prepared from these brush-borders (mostly sealed and right-side-out) fully express the proteinase activity as judged by the fact that there is no increase in activity upon rupture or solubilization of the vesicles. Although the brush-border vesicles contain a cAMP-dependent protein kinase, this membrane-bound kinase is not likely to be the physiological target of the proteinase, since it appears to have an intracellular orientation and, at least in the vesicles, to be inaccessible to the proteinase. It is, therefore, suggested that the physiological substrate of the proteinase might be either an extracellular cAMP-dependent protein kinase, which is lost (e.g. removed, inactivated or degraded) in the course of vesicle isolation, or a kinase domain in one of the family of proteins recently shown to have a considerable structural and conformational homology with C. Alternatively the physiological site of action of this kinase-splitting proteinase might be an intracellular organelle to which it is translocated by endocytosis.

  20. Immunoelectrophoretic studies on pig intestinal brush border proteins

    DEFF Research Database (Denmark)

    Danielsen, Erik Michael; Sjöström, H; Norén, O

    1977-01-01

    aminopeptidase (EC 3.4.11.2), aspartate aminopeptidase (EC 3.4.11.7), dipeptidyl peptidase IV (EC 3.4.14.X), lactase (EC 3.2.1.23), glucoamylase (EC 3.2.1.3), sucrase (EC 3.2.1.48), isomaltase (EC 3.2.1.10) and alkaline phosphatase (EC 3.1.3.1). In addition, at least four faint immunoprecipitates were formed...

  1. Renal brush border enzyme-cleavable linkages for low renal radioactivity levels of radiolabeled antibody fragments.

    Science.gov (United States)

    Akizawa, Hiromichi; Imajima, Mitsuo; Hanaoka, Hirofumi; Uehara, Tomoya; Satake, Satoshi; Arano, Yasushi

    2013-02-20

    We previously demonstrated that Fab fragments labeled with 3'-[(131)I]iodohippuryl N(ε)-maleoyl-l-lysine ([(131)I]HML) showed low renal radioactivity from early postinjection time, due to a liberation of m-[(131)I]iodohippuric acid by the action of renal brush border enzymes. Since there are lots of enzymes on renal brush border membrane, peptide linkages other than the glycyl-l-lysine were evaluated as the cleavable linkages to explore the chemical design. In this study, we evaluated four peptide linkages with a general formula of m-iodobenzoyl-glycyl-X (X: l-tyosine O-methyl, l-asparagine, l-glutamine, and N(ε)-Boc-l-lysine). In vitro studies using renal brush border membrane vesicles (BBMVs) demonstrated that 3'-[(125)I]iodohippuryl O-methyl-l-tyrosine (2c) liberated the highest amount of m-[(125)I]iodohippuric acid among the four substrates and the change in the linkage structure altered enzyme species responsible for the hydrolysis reaction. To further assess the applicability of the linkage, a radioiodination reagent containing a glycyl-tyrosine linkage, 3'-[(125)I]iodohippuryl O-((2-maleimidoethyl)carbamoyl)methyl-l-tyrosine (HMT, 12c), was designed, synthesized, and subsequently conjugated to an Fab fragment. [(125)I]HMT-Fab exhibited renal radioactivity levels similar to and significantly lower than [(125)I]HML-Fab and directly radioiodinated Fab, while the blood clearance rates of the three were similar. The analyses of urine for 24 h postinjection of [(125)I]HMT-Fab showed that m-[(125)I]iodohippuric acid was excreted as the major radiometabolite. The findings indicated that glycyl-tyrosine linkage is also available to reduce renal radioactivity levels of radioiodinated Fab fragments, due to liberation of m-iodohippuric acid by the action of enzymes present on renal brush border membrane. These findings suggest that an appropriate selection of peptide linkages would allow the liberation of a designed radiolabeled compound from covalently conjugated

  2. Thyroid hormones increase Na -H exchange activity in renal brush border membranes

    Energy Technology Data Exchange (ETDEWEB)

    Kinsella, J.; Sacktor, B.

    1985-06-01

    Na -H exchange activity, i.e., amiloride-sensitive Na and H flux, in renal proximal tubule brush border (luminal) membrane vesicles was increased in the hyperthyroid rat and decreased in the hypothyroid rat, relative to the euthyroid animal. A positive correlation was found between Na -H exchange activity and serum concentrations of thyroxine (T4) and triiodothyronine (T3). The thyroid status of the animal did not alter amiloride-insensitive Na uptake. The rate of passive pH gradient dissipation was higher in membrane vesicles from hyperthyroid rats compared to the rate in vesicles from hypothyroid animals, a result which would tend to limit the increase in Na uptake in vesicles from hyperthyroid animals. Na -dependent phosphate uptake was increased in membrane vesicles from hyperthyroid rats; Na -dependent D-glucose and L-proline uptakes were not changed by the thyroid status of the animal. The effect of thyroid hormones in increasing the uptake of Na in the brush border membrane vesicle is consistent with the action of the hormones in enhancing renal Na reabsorption.

  3. Deep-apical tubules: dynamic lipid-raft microdomains in the brush-border region of enterocytes

    DEFF Research Database (Denmark)

    Hansen, Gert H; Pedersen, Jens; Niels-Christiansen, Lise-Lotte

    2003-01-01

    microdomains. Deep-apical tubules were positioned close to the actin rootlets of adjacent microvilli in the terminal web region, which had a diameter of 50-100 nm, and penetrated up to 1 microm into the cytoplasm. Markers for transcytosis, IgA and the polymeric immunoglobulin receptor, as well as the resident...... lipid raft-containing compartments, but little is otherwise known about these raft microdomains. We therefore studied in closer detail apical lipid-raft compartments in enterocytes by immunogold electron microscopy and biochemical analyses. Novel membrane structures, deep-apical tubules, were visualized...... brush-border enzyme aminopeptidase N, were present in these deep-apical tubules. We propose that deep-apical tubules are a specialized lipid-raft microdomain in the brush-border region functioning as a hub in membrane trafficking at the brush border. In addition, the sensitivity to cholesterol depletion...

  4. Effect of increasing the proportion of dietary concentrate on gastrointestinal tract measurements and brush border enzyme activity in Holstein steers.

    Science.gov (United States)

    Górka, P; Schurmann, B L; Walpole, M E; Błońska, A; Li, S; Plaizier, J C; Kowalski, Z M; Penner, G B

    2017-06-01

    The aim of this study was to determine the time course for adaptation of the reticulo-rumen, omasum, abomasum, and small intestine in response to an abrupt increase in the proportion of grain in the diet. Adaptive responses include tissue and digesta mass, small intestinal length, and brush border enzyme activity in the duodenum, proximal jejunum, and ileum. Twenty-five Holstein steers (213 ± 23 kg; 5 to 7 mo of age) were blocked by body weight, and within block were randomly assigned to 1 of 5 treatments: the control diet (CTRL; 92% chopped grass hay and 8% mineral and vitamin supplement on a dry matter basis) or a moderate grain diet (MGD; 50% chopped grass hay, 42% rolled barley grain, and 8% mineral and vitamin supplement) that was fed for 3 (MGD3), 7 (MGD7), 14 (MGD14), or 21 d (MGD21). Dry matter intake was limited to 2.25% of body weight to ensure that changes in dry matter intake did not confound the results. On the last day of the dietary exposure, steers were slaughtered 2 h after feeding. Reticulo-rumen tissue mass and ruminal epithelium mass in the ventral sac of the rumen were not affected by the MGD. Wet reticulo-ruminal digesta mass decreased from CTRL to MGD7 and then increased, but reticulo-ruminal digesta dry matter mass did not differ between treatments. Omasal mass, omasal tissue mass, and omasum digesta mass decreased linearly with the number of days fed MGD, but abomasal tissue mass tended to increase linearly. Duodenal tissue mass tended to increase linearly, and ileal length increased linearly with the number of days fed MGD. Lactase activity in the proximal jejunum increased linearly and maltase activity in duodenum tended to increase linearly with days fed MGD. Aminopeptidase N activity in the proximal jejunum increased cubically with days fed MGD, and dipeptidylpeptidase IV activity in ileum tended to decrease from CTRL to MGD14 and then tended to increase. Adaptation to a diet with a greater proportion of concentrate involves changes in

  5. Rotavirus NSP4114-135 peptide has no direct, specific effect on chloride transport in rabbit brush-border membrane

    Directory of Open Access Journals (Sweden)

    Vasseur Monique

    2006-11-01

    Full Text Available Abstract The direct effect of the rotavirus NSP4114-135 and Norovirus NV464-483 peptides on 36Cl uptake was studied by using villus cell brush border membrane (BBM isolated from young rabbits. Both peptides inhibited the Cl-/H+ symport activity about equally and partially. The interaction involved one peptide-binding site per carrier unit. Whereas in vitro NSP4114-135 caused nonspecific inhibition of the Cl-/H+ symporter, the situation in vivo is different. Because rotavirus infection in young rabbits accelerated both Cl- influx and Cl- efflux rates across villi BBM without stimulating Cl- transport in crypt BBM, we conclude that the NSP4114-135 peptide, which causes diarrhea in young rodents, did not have any direct, specific effect on either intestinal absorption or secretion of chloride. The lack of direct effect of NSP4 on chloride transport strengthens the hypothesis that NSP4 would trigger signal transduction pathways to enhance net chloride secretion at the onset of rotavirus diarrhea.

  6. Lipid rafts exist as stable cholesterol-independent microdomains in the brush border membrane of enterocytes

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Immerdal, Lissi; Thorsen, Evy

    2001-01-01

    Glycosphingolipid/cholesterol-rich membranes ("rafts")can be isolated from many types of cells, but their existence as stable microdomains in the cell membrane has been elusive. Addressing this problem, we studied the distribution of galectin-4, a raft marker, and lactase, a protein excluded from...... rafts, on microvillar vesicles from the enterocyte brush border membrane. Magnetic beads coated with either anti-galectin-4 or anti-lactase antibodies were used for immunoisolation of vesicles followed by double immunogold labeling of the two proteins. A morphometric analysis revealed subpopulations...... of raft-rich and raft-poor vesicles by the following criteria: 1) the lactase/galectin-4 labeling ratio/vesicle captured by the anti-lactase beads was significantly higher (p

  7. H+ V-ATPase-Energized Transporters in Brush Border Membrane Vesicles from Whole Larvae of Aedes Aegypti

    Science.gov (United States)

    Brush Border Membrane vesicles (BBMVs) from Whole larvae of Aedes aegypti (AeBBMVWs ) contain an H+ V-ATPase (V), a Na+/H+ antiporter, NHA1 (A) and a Na+-coupled, nutrient amino acid transporter, NAT8 (N), VAN for short. All V-ATPase subunits are present in the Ae. aegypti genome and in the vesicles...

  8. Generation of stable lipid raft microdomains in the enterocyte brush border by selective endocytic removal of non-raft membrane

    DEFF Research Database (Denmark)

    Danielsen, E Michael; Hansen, Gert H

    2013-01-01

    functions to enrich the contents of lipid raft components in the brush border. The lipophilic fluorescent marker FM, taken up into early endosomes in the terminal web region (TWEEs), was absent from detergent resistant membranes (DRMs), implying an association with non-raft membrane. Furthermore, neither...

  9. Characteristics of glutamine transport in dog jejunal brush-border membrane vesicles.

    Science.gov (United States)

    Bulus, N M; Abumrad, N N; Ghishan, F K

    1989-07-01

    The present study characterizes glutamine transport across brush-border membrane vesicles (BBMV) prepared from dog jejunum. The purity of these vesicles was demonstrated by a 20-fold enrichment of leucine aminopeptidase, a marker for BBM. Glutamine uptake was found to occur into an osmotically active space with no membrane binding and to exhibit temperature and pH dependence (optimal uptake at pH 7-7.5). Glutamine uptake was driven by an inwardly directed Na+ gradient with a distinct overshoot not observed under K+ gradient. Lithium could not substitute for Na+ as a stimulator of glutamine uptake. Na+-dependent glutamine uptake was not inhibited by methylaminoisobutyric acid, a typical substrate for system A, and was found to be electrogenic and saturable with a Km of 0.97 +/- 0.58 mM and a Vmax of 3.93 +/- 0.99 nmol.mg protein-1.10 s-1. A Na+-glutamine coupling ratio of 1:1 could be demonstrated by a plot of Hill transformation. Na+-independent glutamine uptake was found to be electroneutral and saturable with a Km of 3.70 +/- 0.66 mM and a Vmax of 2.70 +/- 1.55 nmol.mg protein-1.10 s-1. Inhibition studies confirmed the presence of a Na+-dependent as well as a Na+-independent carrier for glutamine uptake. We conclude that glutamine uptake across dog BBMV occurs via two transport systems: a Na+-dependent high-affinity system similar to the neutral brush-border system and a Na+-independent lower-affinity system similar to system L.

  10. Peritubular uptake and brush border transport of 28Mg by flounder renal tubules

    International Nuclear Information System (INIS)

    Renfro, J.L.; Shustock, E.

    1985-01-01

    The uptake of 28 Mg by isolated renal tubules of winter flounder, Pseudopleuronectes americanus, was studied by compartmental analysis. Two phases of uptake were seen in steady-state conditions. The slow-exchanging compartment was 46% of the total Mg content, and uptake into this compartment was saturable and inhibited by 10 mM CaCl 2 , dinitrophenol, and ouabain but not by furosemide, Na-free medium, or cytochalasin B. The fast-exchanging compartment was 5% of the total Mg, and uptake into this compartment showed sigmoid saturation kinetics. The fast uptake rate was inhibited by dinitrophenol, ouabain, Na-free medium, 10 mM CaCl 2 , and furosemide but stimulated by cytochalasin B. 28 Mg efflux from brush border membrane vesicles (BBMV) was stimulated by both an inside positive electrical potential generated by 100 mM KCl and by 100 mM NaCl. BBMV uptake was inhibited by 10 mM CaCl 2 and unaffected by furosemide. The relationship of electrical gradient-driven and Na gradient-driven Mg transport to the Mg secretory function of these tubules is discussed

  11. Cimetidine transport in rabbit renal cortical brush-border membrane vesicles

    Energy Technology Data Exchange (ETDEWEB)

    McKinney, T.D.; Kunnemann, M.E.

    1987-03-01

    Cimetidine is an organic cation and commonly prescribed drug that is eliminated primarily by proximal renal tubular secretion. The present studies evaluated cimetidine transport in rabbit renal cortical brush-border membrane vesicles (BBMV). (/sup 3/H)Cimetidine uptake varied inversely with media osmolarity and was stimulated with uphill transport above equilibrium values (overshoot) produced by an initial proton gradient directed from the vesicle interior outwardly. Uphill transport occurred earlier and was of greater magnitude at 25/sup 0/C than at 5/sup 0/C. pH-stimulated (/sup 3/H)cimetidine uptake was inhibited by excess nonradiolabeled cimetidine, quinidine, and procainamide but was affected little by probenecid. Tetraethylammonium inhibited cimetidine uptake in the presence and absence of an initial proton gradient, indicating that nonionic diffusion and simple diffusion cannot totally account for cimetidine transport in BBMV. Preloading BBMV with an excess of procainamide enhanced cimetidine uptake. These results are consistent with the hypothesis that cimetidine is transported across BBMV by organic cation-proton exchange.

  12. Effect of alpha interferon on glucose and alanine transport by rat renal brush border membrane vesicles

    International Nuclear Information System (INIS)

    Batuman, V.; Chadha, I.

    1990-01-01

    To investigate the pathogenetic mechanisms of interferon nephrotoxicity, we studied the effect of recombinant interferon alfa-2b on the uptake of 14 C-D-glucose and 14 C-L-alanine by rat renal brush-border-membrane vesicles. Interferon significantly inhibited 20 sec. sodium-dependent and 5 and 10 min. equilibrium uptake of both glucose and alanine. The inhibitory effect was dose dependent with maximum effect achieved at interferon concentration of 5 x 10 -8 M in the uptake media. The half-maximal inhibitory concentrations, IC 50 , of interferon on glucose uptake was 1.8 x 10 -8 M, and 5.4 x 10 -9 M on alanine uptake. Dixon plot analysis of uptake data was consistent with pure non-competitive inhibition. The inhibition constants, K i , 1.5 x 10 -8 M for glucose uptake, and 7.3 x 10 -9 M for alanine uptake, derived from Dixon plots were in close agreement with the IC 50 s calculated from the semilog dose response curves. These observations reveal that direct interactions at the proximal tubule cell membrane are involved in the pathogenesis of interferon nephrotoxicity, and that its mechanism of nephrotoxicity is similar to that of other low molecular weight proteins

  13. Transport of acidic amino acids by human jejunal brush-border membrane vesicles

    International Nuclear Information System (INIS)

    Rajendran, V.M.; Harig, J.M.; Adams, M.B.; Ramaswamy, K.

    1987-01-01

    This study characterizes the transport of radiolabeled acidic amino acids into brush-border membrane vesicles prepared from human jejunum. The uptakes of L-glutamic, L-aspartic, and D-aspartic acids were stimulated by a Na + gradient. Concentrative uptake (resulting in an overshoot phenomenon) of these dicarboxylic amino acids occurred when there was an outward K + gradient. In addition, increasing K + gradients resulted in enhanced uptake of L-glutamic acid. This K + requirement is somewhat specific as Rb + and Cs + could enhance uptake to a limited extent, whereas Li + and choline + showed no enhancement. The presence of a K + gradient did not affect the affinity of the carrier system for L-glutamic acid but it did increase the V/sub max/. The presence of extravesicular anions having differing membrane permeabilities did not altar L-glutamic acid uptake indicating an absence of an effect of membrane potential on the transport process. Finally, the human transport system for L-glutamic acid appears to be specific for acidic amino acids as demonstrated by inhibition studies. The studies demonstrate a transport system in human jejunum specific for acidic amino acids that is energized by an inward Na + gradient and an outward K + gradient

  14. Uptake and binding of 125I-calmodulin by isolated rat renal brush border membrane vesicles

    International Nuclear Information System (INIS)

    Meezan, E.; Elgavish, A.; Wallace, R.W.

    1986-01-01

    The authors have investigated the interaction of 125 I-calmodulin with isolated rat renal brush border membrane vesicles (BBV) using an experimental protocol which allows us to distinguish between ligand binding to the outside of the vesicles vs. uptake and possible binding to the vesicle interior. By examining the association of 125 I-calmodulin with BBV as a function of medium osmolarity (300-1100 mosm) to alter intravesicular space, virtually all ligand interaction with BBV was found to represent uptake of intact 125 I-calmodulin into the intravesicular space. Uptake appeared specific by the following criteria: (1) it was largely calcium dependent (2) it was inhibited in a dose dependent fashion by calmodulin and the homologous protein troponin C, but not by unrelated proteins (lysozyme, cytochrome C, insulin) (3) it was inhibited by known calmodulin antagonists (calmidazolium, mellitin, trifluoperazine). Calmodulin uptake may be followed by binding of 125 I-calmodulin to intravesicular BBV proteins; calmodulin-binding proteins in BBV with molecular weights of 143K, 118K, 50K, 47.5K, 46.5K and 35K were identified by Western blotting techniques. The specific association of 125 I-calmodulin with isolated BBV is of interest in regard to the possible role of this calcium regulatory protein in the protein reabsorptive and ion transport functions of this renal tubular membrane fraction

  15. Natural Selection at the Brush-Border: Adaptations to Carbohydrate Diets in Humans and Other Mammals.

    Science.gov (United States)

    Pontremoli, Chiara; Mozzi, Alessandra; Forni, Diego; Cagliani, Rachele; Pozzoli, Uberto; Menozzi, Giorgia; Vertemara, Jacopo; Bresolin, Nereo; Clerici, Mario; Sironi, Manuela

    2015-08-28

    Dietary shifts can drive molecular evolution in mammals and a major transition in human history, the agricultural revolution, favored carbohydrate consumption. We investigated the evolutionary history of nine genes encoding brush-border proteins involved in carbohydrate digestion/absorption. Results indicated widespread adaptive evolution in mammals, with several branches experiencing episodic selection, particularly strong in bats. Many positively selected sites map to functional protein regions (e.g., within glucosidase catalytic crevices), with parallel evolution at SI (sucrase-isomaltase) and MGAM (maltase-glucoamylase). In human populations, five genes were targeted by positive selection acting on noncoding variants within regulatory elements. Analysis of ancient DNA samples indicated that most derived alleles were already present in the Paleolithic. Positively selected variants at SLC2A5 (fructose transporter) were an exception and possibly spread following the domestication of specific fruit crops. We conclude that agriculture determined no major selective event at carbohydrate metabolism genes in humans, with implications for susceptibility to metabolic disorders. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  16. Effect of monoassociation with probiotic strain Bifidobacterium bifidum on enterocyte brush-border enzymes in gnotobiotic mice

    Czech Academy of Sciences Publication Activity Database

    Kozáková, Hana; Řeháková, Zuzana; Kolínská, Jiřina; Tlaskalová, Helena

    2002-01-01

    Roč. 88, č. 1 (2002), s. 113 ISSN 0007-1145. [Probiotics and Health /2001./. London, 13.09.2002-14.09.2002] R&D Projects: GA ČR GA306/99/1383; GA ČR GA310/01/0933; GA AV ČR IAA5020101 Keywords : enterocyte * brush * border Subject RIV: EE - Microbiology, Virology Impact factor: 2.491, year: 2002

  17. Inhibition of beta-amino acid transport by diamide does not involve the brush border membrane surface

    International Nuclear Information System (INIS)

    Chesney, R.W.; Gusowski, N.; Albright, P.

    1985-01-01

    Diamide (dicarboxylic acid bis-(N,N-dimethylamide) has been shown in previous studies to block the uptake of the beta-amino acid taurine at its high affinity transport site in rat renal cortex slices. Diamide may act by increasing the efflux of taurine from the slice. Studies performed in rat slices again indicate enhanced efflux over 8-12 minutes. The time course of reduced glutathione (GSH) depletion from renal cortex is similar, indicating a potential interaction between GSH depletion and inhibition of taurine accumulation. The effect of 9 mM diamide on the Na+ -dependent accumulation of taurine (10 and 250 microM) by brush border membrane vesicles was examined, and the taurine uptake value both initially and at equilibrium was the same in the presence and absence of diamide. Isolation of the brush border surface and subsequent transport studies of taurine are not influenced by diamide. Thus, diamide inhibition of taurine uptake does not involve physiochemical alteration of the membrane surface where active amino acid transport occurs, despite the thiol-oxidizing properties of this agent. Further, these studies suggest that diamide either acts at the basolateral surface, rather than the brush border surface of rat renal cortex or requires the presence of an intact tubule, capable of metabolism, prior to its inhibitory action

  18. 13C-labeled 18 : 2n-6 recovered in brush border membrane phospholipids short time after administration

    DEFF Research Database (Denmark)

    Vistisen, Bodil; Høy, Carl-Erik

    2004-01-01

    The purpose of the present study was to examine the short-term effect of dietary specific structured triacylglycerols (MLM, M = 8:0, L = 18:2n-6), LLL and MMM on the fatty acid composition of brush border membrane (BBM) phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Rats were...... fatty acids in the two phospholipid pools. Minor effects on BBM-PC and BBM-PE fatty acid profiles (mole-%) were observed. The present study demonstrated for the first time incorporation of C-13-labeled 18:2n-6 into BBM-PC 2 hours and 6 hours after intragastric administration of L*L*L* or ML...

  19. Scavenger receptor class B type I (SR-BI) in pig enterocytes: trafficking from the brush border to lipid droplets during fat absorption

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Niels-Christiansen, Lise-Lotte W; Immerdal, Lissi

    2003-01-01

    BACKGROUND: Scavenger receptor class B type I (SR-BI) is known to mediate cellular uptake of cholesterol from high density lipoprotein particles and is particularly abundant in liver and steroidogenic tissues. In addition, SR-BI expression in the enterocyte brush border has also been reported but...... fat, SR-BI is endocytosed from the enterocyte brush border and accumulates in cytoplasmic lipid droplets. Internalisation of the receptor occurs mainly by clathrin coated pits rather than by a caveolae/lipid raft based mechanism....

  20. The ferric-reducing activity of duodenal brush-border membrane vesicles is associated with a b-type haem.

    Science.gov (United States)

    Pountney, D J; Raja, K B; Simpson, R J; Wrigglesworth, J M

    1999-03-01

    Rabbit brush-border membrane vesicles possess ferricyanide reducing activity. This activity is preferentially dependent on NADH as reductant, and can be stimulated by the addition of FMN. The latency of activity observed following vesicle solubilisation suggests that the responsible component is transmembranous, and partially sequestered on the inner-face of the vesicles prior to full solubilisation. Subsequent increases in detergent concentration (> 0.3% w/v lauryl maltoside) were found to be inhibitory. Ferricyanide reducing activity was effectively inhibited by the sulphydryl modifying reagents N-ethyl malemide and p-chloromercuribenzoate, but not by the flavin analogue diphenylene iodonium. The ferric-reducing activity co-purified with a b-type haem when applied to Sephacryl S-200 columns. The putative cytochrome was found to be immunologically distinct from neutrophil cytochrome b558.

  1. Isolation and partial characterization of gypsy moth BTR-270, an anionic brush border membrane glycoconjugate that binds Bacillus thuringiensis Cry1A toxins with high affinity

    Science.gov (United States)

    Algimantas P. Valaitis; Jeremy L. Jenkins; Mi Kyong Lee; Donald H. Dean; Karen J. Garner

    2001-01-01

    BTR-270, a gypsy moth (Lymantria dispar) brush border membrane molecule that binds Bacillus thuringiensis (Bt) Cry1A toxins with high affinity, was purified by preparative gel electrophoresis. Rabbit antibodies specific for the Bt toxin-binding molecule were raised. Attempts to label BTR-270 by protein-directed techniques were...

  2. A Ca-activated K channel from rabbit renal brush-border membrane vesicles in planar lipid bilayers.

    Science.gov (United States)

    Zweifach, A; Desir, G V; Aronson, P S; Giebisch, G H

    1991-07-01

    Rabbit renal brush-border membranes were fused to planar lipid bilayers to gain insight into the nature and properties of ion channels from the luminal membrane of the proximal tubule. Fusion was obtained using osmotic gradients. A large conductance channel was commonly observed. Measurements of reversal potentials indicated that the channel was selective for K over Rb, Na, and Cl. Channel open probability was increased by membrane depolarization and by increased Ca activity on the intracellular face of the channel. The channel was inhibited by charybdotoxin (CTX), a protein from leiurus venom, from the external side of the channel. The channel was also blocked by Ba and quinidine added to the intracellular bathing solution. Na added to the intracellular bathing solution reduced current amplitude in a voltage-dependent fashion. In addition, methylisobutyl amiloride, an analogue of the K-sparing diuretic amiloride, inhibited channel activity when added to the external solution. The possible physiological role of the channel is discussed. The usefulness to the study of renal ion channels of the technique of fusing membrane vesicles to planar lipid bilayers is evaluated.

  3. 13C-labeled 18 : 2n-6 recovered in brush border membrane phospholipids short time after administration

    DEFF Research Database (Denmark)

    Vistisen, Bodil; Høy, Carl-Erik

    2004-01-01

    The purpose of the present study was to examine the short-term effect of dietary specific structured triacylglycerols (MLM, M = 8:0, L = 18:2n-6), LLL and MMM on the fatty acid composition of brush border membrane (BBM) phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Rats were...... administered intragastrically a bolus of ML*M, M*LM*, L*L*L* or M*M*M* (* = C-13- labeled fatty acid). Rats were decapitated 2 hours and 6 hours later, and the fatty acid composition and C-13-enrichment of BBM-PC and -PE were determined. C-13-enriched 18:2n-6 was observed in BBM-PC after intragastric...... administration of L*L*L* and ML*M, whereas no C-13-labeled fatty acids were recovered after administration of M*LM* or M*M*M*. Interestingly, no C-13-labeled fatty acids were detected in the BBM-PE fraction. This could be due to a lower turnover of PE than PC and to a different ratio of saturated and unsaturated...

  4. Binding and degradation of 125I-insulin by isolated rat renal brush border membranes: evidence for low affinity, high capacity insulin recognition sites

    International Nuclear Information System (INIS)

    Meezan, E.; Pillion, D.J.; Elgavish, A.

    1988-01-01

    The kidney plays a major role in the handling of circulating insulin in the blood, primarily via reuptake of filtered insulin at the luminal brush border membrane. 125I-insulin associated with rat renal brush border membrane vesicles (BBV) in a time- and temperature-dependent manner accompanied by degradation of the hormone to trichloroacetic acid (TCA)-soluble fragments. Both association and degradation of 125I-insulin were linearly proportional to membrane protein concentration with virtually all of the degradative activity being membrane associated. Insulin, proinsulin and desoctapeptide insulin all inhibited the association and degradation of 125I-insulin by BBV, but these processes were not appreciably affected by the insulin-like growth factors IGF-I and IGF-II or by cytochrome c and lysozyme, low molecular weight, filterable, proteins, which are known to be reabsorbed in the renal tubules by luminal endocytosis. When the interaction of 125I-insulin with BBV was studied at various medium osmolarities (300-1100 mosM) to alter intravesicular space, association of the ligand with the vesicles was unaffected, but degradation of the ligand by the vesicles decreased progressively with increasing medium osmolarity. Therefore, association of 125I-insulin to BBV represented binding of the ligand to the membrane surface and not uptake of the hormone or its degradation products into the vesicles. Attempts to crosslink 125I-insulin to a high-affinity insulin receptor using the bifunctional reagent disuccinimidyl suberate revealed only trace amounts of an 125I-insulin-receptor complex in brush border membrane vesicles in contrast to intact renal tubules where this complex was readily observed. Both binding and degradation of 125I-insulin by brush border membranes did not reach saturation even at concentrations of insulin approaching 10(-5) M

  5. Differential Effect of Bacillus firmus on Immune Response and Enterocyte Brush-Border Levels in BALB/c and B10.BR Mice

    Czech Academy of Sciences Publication Activity Database

    Kozáková, Hana; Mlčková, P.; Kolínská, Jiřina; Čechová, D.; Štěpánková, Renata; Řeháková, Zuzana; Prokešová, L.

    2002-01-01

    Roč. 47, č. 6 (2002), s. 759-765 ISSN 0015-5632 R&D Projects: GA ČR GA303/00/1370; GA AV ČR IAA5020101 Institutional research plan: CEZ:AV0Z5020903; CEZ:MSM 111100005 Keywords : brush- border membrane vesicles * bbacillus firmus Subject RIV: EE - Microbiology, Virology Impact factor: 0.979, year: 2002

  6. Restoring effect of selenium on the molecular content, structure and fluidity of diabetic rat kidney brush border cell membrane.

    Science.gov (United States)

    Gurbanov, Rafig; Bilgin, Mehmet; Severcan, Feride

    2016-04-01

    Diabetic kidney disease (DKD) is a dominant factor standing for kidney impairments during diabetes. In this study, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy was used to disclose the diabetes-induced structural changes in the kidney and evaluate the effects of selenium on diabetes. The increase in the area of the olefinic band indicated increased amount of lipid peroxidation end products in diabetic kidney brush border cell membrane. Moreover, saturated lipid content of this cell membrane considerably diminished. DKD was found to disrupt lipid order and cause a decrease in membrane dynamics. However, the administration of selenium at low and medium doses was shown to improve these conditions by changing the lipid contents toward control values, restoring the ordered structure of the lipids and membrane dynamics. Curve-fitting and artificial neural network (ANN) analyses of secondary structures of proteins demonstrated a relative increase in α-helix and reduction in the β-sheet during diabetes in comparison to the control group, which were ameliorated following selenium treatment at low and medium doses. These findings were further confirmed by applying hierarchical cluster analysis (HCA) and principal component analysis (PCA). A clear separation of the experimental groups was obtained with high heterogeneity in the lipid and protein regions. These chemometric analyses showed that the low and medium doses of selenium-treated diabetic groups are successfully segregated from the diabetic group and clustered closer to the control. The study suggests that medium and, more predominantly, low-dose selenium treatment can be efficient in eliminating diabetes-induced structural alterations. Copyright © 2016 Elsevier B.V. All rights reserved

  7. Inhibition of renal brush border phosphate transport and stimulation of renal gluconeogenesis by cyclic amp and parathyroid hormone.

    Science.gov (United States)

    Kempson, S A; Kowalski, J C; Puschett, J B

    1983-05-01

    The aims of the study were to determine whether 8-bromo-cyclic AMP (8BcAMP) in vivo mimics the inhibitory action of parathyroid hormone (PTH) on phosphate transport across the brush border membrane (BBM) of the renal proximal tubule, and to examine whether changes in BBM transport are accompanied by changes in the rate of renal gluconeogenesis. Thyroparathyroidectomized dogs were anesthetized and equilibrated, and control urine collections were obtained prior to removing the left kidney. Subsequent intravenous infusion of 8BcAMP at 50 mg/hr for 2 hr increased fractional excretion of phosphate from 4 +/- 1 (controls) to 29 +/- 4% (P less than 0.001) without changing glomerular filtration. In BBM vesicles isolated from the renal cortex, the initial Na+-dependent transport of phosphate was decreased from 747 +/- 135 (controls) to 564 +/- 126 pmoles per mg per 0.25 min after 8BcAMP (P less than 0.025), but Na+-independent phosphate uptake and Na+-dependent L-proline uptake were not changed significantly. Renal gluconeogenesis in the same animals was increased from 2.5 +/- 0.3 (controls) to 5.3 +/- 0.5 mumoles glucose per g tissue per hr after infusion of 8BcAMP (P less than 0.001). Infusion of PTH, like 8BcAMP, inhibited BBM phosphate transport and stimulated renal gluconeogenesis. We conclude that the inhibitory action of cyclic AMP and PTH on BBM phosphate transport is accompanied by stimulation of gluconeogenesis which suggests, indirectly, that changes in gluconeogenesis may be part of the intracellular mechanism for regulating BBM phosphate uptake in response to certain stimuli.

  8. Angiotensin 2 directly increases rabbit renal brush-border membrane sodium transport: Presence of local signal transduction system

    Energy Technology Data Exchange (ETDEWEB)

    Morduchowicz, G.A.; Sheikh-Hamad, D.; Dwyer, B.E.; Stern, N.; Jo, O.D.; Yanagawa, N. (Sepulveda Veterans Administration, CA (USA))

    1991-05-01

    In the present study, the authors have examined the direct actions of angiotensin II (AII) in rabbit renal brush border membrane (BBM) where binding sites for AII exist. Addition of AII (10(-11)-10(-7) M) was found to stimulate 22Na+ uptake by the isolated BBM vesicles directly. All did not affect the Na(+)-dependent BBM glucose uptake, and the effect of AII on BBM 22Na+ uptake was inhibited by amiloride, suggesting the involvement of Na+/H+ exchange mechanism. BBM proton permeability as assessed by acridine orange quenching was not affected by AII, indicating the direct effect of AII on Na+/H+ antiport system. In search of the signal transduction mechanism, it was found that AII activated BBM phospholipase A2 (PLA) and that BBM contains a 42-kDa guanine nucleotide-binding regulatory protein (G-protein) that underwent pertussis toxin (PTX)-catalyzed ADP-ribosylation. Addition of GTP potentiated, while GDP-beta S or PTX abolished, the effects of AII on BBM PLA and 22Na+ uptake, suggesting the involvement of G-protein in AII's actions. On the other hand, inhibition of PLA by mepacrine prevented AII's effect on BBM 22Na+ uptake, and activation of PLA by mellitin or addition of arachidonic acid similarly enhanced BBM 22Na+ uptake, suggesting the role of PLA activation in mediating AII's effect on BBM 22Na+ uptake. In summary, results of the present study show a direct stimulatory effect of AII on BBM Na+/H+ antiport system, and suggest the presence of a local signal transduction system involving G-protein mediated PLA activation.

  9. Murine intestinal cells expressing Trpm5 are mostly brush cells and express markers of neuronal and inflammatory cells.

    Science.gov (United States)

    Bezençon, C; Fürholz, A; Raymond, F; Mansourian, R; Métairon, S; Le Coutre, J; Damak, S

    2008-08-10

    To determine the role in chemosensation of intestinal solitary cells that express taste receptors and Trpm5, we carried out a microarray study of the transcriptome of FACS-sorted transgenic mouse intestinal cells expressing enhanced green fluorescent protein (eGFP) under the control of the Trpm5 promoter and compared it with that of intestinal cells that do not express eGFP. The findings of the study are: 1) Morphology and expression of markers show that most eGFP+ cells are brush cells. 2) The majority of proteins known to be involved in taste signal transduction are expressed in the eGFP+ cells, although the isoforms are not always the same. 3) eGFP+ cells express pre- and postsynaptic markers and nerves are often found in close proximity. 4) Several genes that play a role in inflammation are expressed specifically in eGFP+ cells. Furthermore, these cells express the entire biosynthesis pathway of leucotriene C4, an eicosanoid involved in modulation of intestinal smooth muscle contraction. 5) Angiotensinogen, renin, and succinate receptor genes are expressed in the eGFP+ cells, suggesting a role in the regulation of water and sodium transport, vasomotricity, and blood pressure. These data suggest that the Trpm5-expressing cells integrate many signals, including chemical signals from ingested food, and that they may regulate several physiological functions of the gastrointestinal tract. (c) 2008 Wiley-Liss, Inc.

  10. Dietary free fatty acids form alkaline phosphatase-enriched microdomains in the intestinal brush border membrane

    DEFF Research Database (Denmark)

    Hansen, Gert H; Rasmussen, Karina; Niels-Christiansen, Lise-Lotte

    2011-01-01

    mimicking a physiological solution of dietary mixed micelles, rearranged the lipid raft microdomain organization of the membranes. Thus, the fat mixture generated a low-density subpopulation of microvillar detergent resistant membranes (DRMs) highly enriched in alkaline phosphatase (AP). Since this GPI...

  11. The effect of the physical effort on the activity of brush border enzymes and lysosomal enzymes of nephron excreted in the urine

    Directory of Open Access Journals (Sweden)

    E Bakońska-Pacoń

    2003-03-01

    Full Text Available The lysosomal enzymes activities in the athletes urine were designated and presented in this work: N-acetyl-ß-D-glucosaminidase (NAG, ß-glucuronidase (GSR, arylsulfatase A (ASA. The brush border enzymes activities: leucyloaminopeptidase (LAP, alanine aminopeptidase (AAP, ?-glutamyltransferaze (GGT, the trypsin inhibitor activity (UTI and the total protein and creatinine concentrations were determined as well. Values of examined parameters are presented after its conversion to mmol creatinine units. Nine athletes subjected to physical effort in the frame of the training unit with the speed endurance accent were taken under the examination. The urine was taken before, immediately after and 24 h after effort. 9-fold increase of the protein/creatinine index was observed in the postexercise urine. In the urine taken after next 24h this index decreased to over 2-fold higher value than it presented itself before effort. Almost 3-fold increase of the NAG activity and 4-fold decrease of the ASA activity were noticed in the after effort urine. The brush border enzymes values were higher for over 2-3-fold in the postexercise urine but after next 24h they went down below values observed before effort. The correlation between NAG and brush border enzymes was observes at the level of r=0.7. All changes of examined parameters point at the passing glomerular-tubular troubles of nephrons. It may also be suggested that various forms of changes in the lysosomal enzymes activity are connected with their functions in organism and not with the degree of the renal cells structure damage.

  12. Stimulation of calcium uptake by parathyroid hormone in renal brush-border membrane vesicles. Relationship to membrane phosphorylation.

    Science.gov (United States)

    Khalifa, S; Mills, S; Hruska, K A

    1983-12-10

    The effect of parathyroid hormone (PTH) on Ca2+ uptake was studied in brush-border membrane vesicles (BBMV) prepared from the kidneys of dogs administered 4-5 micrograms/kg of bovine PTH 1-84 in vivo. PTH stimulated Ca2+ uptake at 20 s of incubation from control values of 231 +/- 21 to 306 +/- 30 pmol/mg of protein, p less than 0.001. The stimulation of Ca2+ uptake by PTH was not reversed by incubation of the BBMV with the Ca2+ ionophore, despite the fact that Ca2+ uptake was several times greater than the expected uptake at equilibrium, indicating that most of the uptake represented Ca2+ binding to the BBMV. In BBMV from kidneys exposed to PTH, hypotonic lysis or increasing the osmolality of the solution external to the BBMV did not affect Ca2+ uptake. These data also indicated that the largest fraction of Ca2+ uptake in the presence of a chemical potential represented binding of Ca2+ to BBMV. Ca2+ binding was initially to the exterior of the BBMV, then translocated within the membrane and to the interior vesicular face as assessed by chelation of Ca2+ bound to the BBMV by ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid. Incubation of BBMV from kidneys exposed to PTH with gentamicin, which competes with Ca2+ for anionic phospholipid-binding sites, reversed the stimulatory effects of PTH on Ca2+ uptake. Phosphorylation of BBMV and PTH treatment in vivo had similar effects on BBMV phospholipid composition increasing the levels of anionic phospholipids. Phosphorylation of the BBMV also produced gentamicin-inhibitable increases in membrane Ca2+ binding. Phosphorylation of BBMV from kidneys exposed to PTH was inhibited suggesting a higher state of phosphorylation in vivo. The data demonstrate that PTH administered in vivo stimulated Ca2+ binding in BBMV that was gentamicin inhibitable and associated with an increase in the membrane content of anionic phospholipids.

  13. The effect of cadmium chloride in vitro on sodium-glutamate cotransport in brush border membrane vesicles isolated from rabbit kidney.

    Science.gov (United States)

    Kinne, R K; Schütz, H; Kinne-Saffran, E

    1995-12-01

    To further elucidate the mechanism of cadmium inhibition of renal amino acid transport, brush border membrane vesicles were isolated from rabbit renal cortex and the effect of cadmium on the uptake of L-glutamate into the vesicles was investigated. Preincubation of the membranes with CdCl2 decreased sodium-dependent L-glutamate uptake at concentrations higher than 10(-6)M. In the presence of 20 mM potassium inside the vesicles a half-maximal inhibition was observed at 0.5 to 1 x 10(-4) M. Kinetic analysis revealed a strong reduction of Vmax by cadmium but only minor changes in Km for glutamate. The inhibition required preincubation of the vesicles with cadmium, was not elicited by cadmium metallothionein, and was not reversed by ethylenediaminetetraacetic acid. These findings suggest an action of cadmium at the cytoplasmic face of the brush border membrane. Furthermore, the sensitivity of the transport system for cadmium was lower in the absence of potassium. Inhibition increased in a saturable manner when intravesicular potassium was augmented, indicating that the transporter interacts with cadmium most avidly when potassium is bound to the carrier.

  14. Oral administration of a nephrotoxic dose of potassium bromate, a food additive, alters renal redox and metabolic status and inhibits brush border membrane enzymes in rats.

    Science.gov (United States)

    Ahmad, Mir Kaisar; Naqshbandi, Ashreeb; Fareed, Mohd; Mahmood, Riaz

    2012-09-15

    The time dependent effect of orally administered KBrO(3) on redox status and enzymes of brush border membrane (BBM) and carbohydrate metabolism has been studied in rat kidney. Animals were given a single oral dose of KBrO(3) (100mg/kg body weight) and sacrificed at different times after this treatment; control animals were not given KBrO(3). The administration of KBrO(3) resulted in nephrotoxicity, a decline in the specific activities of several BBM marker enzymes and also induced oxidative stress in kidney. The specific activities of enzymes of carbohydrate metabolism were also altered and suggest a shift in energy metabolism from the aerobic to anaerobic mode. The renal effects of single oral dose of KBrO(3) appeared to be reversible; maximum changes in all the parameters were 48 h after administration of KBrO(3) after which recovery took place, in many cases almost to control values, after 168 h. These results suggest that the administration of a single nephrotoxic dose of KBrO(3) inhibits brush border membrane enzymes, induces oxidative stress and alters energy metabolism of the renal system in a reversible manner. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Specificity of Bacillus thuringiensis endotoxins is correlated with the presence of high-affinity binding sites in the brush border membrane of target insect midguts

    International Nuclear Information System (INIS)

    Hofmann, C.; Vanderbruggen, H.; Hoefte, H.; Van Rie, J.; Jansens, S.; Van Mellaert, H.

    1988-01-01

    Binding studies were performed with two 125 I-labeled Bacillus thuringiensis δ-endotoxins on brush border membrane vesicles prepared from the larval midgut of the tobacco hornworm Manduca sexta or the cabbage butterfly Pieris brassicae. One δ-endotoxin, Bt2-protoxin, is a 130-kDa recombinant crystalline protein from B. thuringiensis subsp. berliner. It kills larvae of both insect species. The active Bt2-toxin is a 60-kDa proteolytic fragment of the Bt2-protoxin. It binds saturably and with high affinity to brush border membrane vesicles from the midgut of both species. The other δ-endotoxin, Bt4412-protoxin, is a 136-kDa crystalline protein from B. thuringiensis subsp. thuringiensis, which is highly toxic for P. brassicae, but not for M. sexta larvae. Bt4412-toxin, obtained after proteolytic activation of Bt4412-protoxin, shows high-affinity saturable binding to P. brassicae vesicles but not to M. sexta vesicles. The correlation between toxicity and specific binding is further strengthened by competition studies. Other B. thuringiensis δ-endotoxins active against M. sexta compete for binding of 125 I-labeled Bt2-toxin to M. sexta vesicles, whereas toxins active against dipteran or coleopteran larvae do not compete. Bt2-toxin and Bt4412-toxin bind to different sites on P. brassicae vesicles

  16. Differentiation-dependent activation of the human intestinal alkaline phosphatase promoter by HNF-4 in intestinal cells

    DEFF Research Database (Denmark)

    Olsen, Line; Bressendorff, Simon; Troelsen, Jesper T

    2005-01-01

    The intestinal alkaline phosphatase gene (ALPI) encodes a digestive brush-border enzyme, which is highly upregulated during small intestinal epithelial cell differentiation. To identify new putative promoter motifs responsible for the regulation of ALPI expression during differentiation of the en...

  17. Brush border membrane vesicle and Caco-2 cell line: Two experimental models for evaluation of absorption enhancing effects of saponins, bile salts, and some synthetic surfactants.

    Science.gov (United States)

    Moghimipour, Eskandar; Tabassi, Sayyed Abolghassem Sajadi; Ramezani, Mohammad; Handali, Somayeh; Löbenberg, Raimar

    2016-01-01

    The aim of this study was to investigate the influence of absorption enhancers in the uptake of hydrophilic compounds. The permeation of the two hydrophilic drug models gentamicin and 5 (6)-carboxyfluorescein (CF) across the brush border membrane vesicles and Caco-2 cell lines were evaluated using total saponins of Acanthophyllum squarrosum, Quillaja saponaria, sodium lauryl sulfate, sodium glycocholate, sodium taurodeoxycholate, and Tween 20 as absorption enhancers. Transepithelial electrical resistance (TEER) measurement was utilized to assess the paracellular permeability of cell lines. Confocal laser scanning microscopy (CLSM) was performed to obtain images of the distribution of CF in Caco-2 cells. These compounds were able to loosen tight junctions, thus increasing paracellular permeability. CLSM confirmed the effect of these absorption enhancers on CF transport across Caco-2 lines and increased the Caco-2 permeability via transcellular route. It was also confirmed that the decrease in TEER was transient and reversible after removal of permeation enhancers.

  18. A Tenebrio molitor GPI-anchored alkaline phosphatase is involved in binding of Bacillus thuringiensis Cry3Aa to brush border membrane vesicles.

    Science.gov (United States)

    Zúñiga-Navarrete, Fernando; Gómez, Isabel; Peña, Guadalupe; Bravo, Alejandra; Soberón, Mario

    2013-03-01

    Bacillus thuringiensis Cry toxins recognizes their target cells in part by the binding to glycosyl-phosphatidyl-inositol (GPI) anchored proteins such as aminopeptidase-N (APN) or alkaline phosphatases (ALP). Treatment of Tenebrio molitor brush border membrane vesicles (BBMV) with phospholipase C that cleaves out GPI-anchored proteins from the membranes, showed that GPI-anchored proteins are involved in binding of Cry3Aa toxin to BBMV. A 68 kDa GPI-anchored ALP was shown to bind Cry3Aa by toxin overlay assays. The 68 kDa GPI-anchored ALP was preferentially expressed in early instar larvae in comparison to late instar larvae. Our work shows for the first time that GPI-anchored ALP is important for Cry3Aa binding to T. molitor BBMV suggesting that the mode of action of Cry toxins is conserved in different insect orders. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Brush border membrane vesicle and Caco-2 cell line: Two experimental models for evaluation of absorption enhancing effects of saponins, bile salts, and some synthetic surfactants

    Directory of Open Access Journals (Sweden)

    Eskandar Moghimipour

    2016-01-01

    Full Text Available The aim of this study was to investigate the influence of absorption enhancers in the uptake of hydrophilic compounds. The permeation of the two hydrophilic drug models gentamicin and 5 (6-carboxyfluorescein (CF across the brush border membrane vesicles and Caco-2 cell lines were evaluated using total saponins of Acanthophyllum squarrosum, Quillaja saponaria, sodium lauryl sulfate, sodium glycocholate, sodium taurodeoxycholate , and Tween 20 as absorption enhancers. Transepithelial electrical resistance (TEER measurement was utilized to assess the paracellular permeability of cell lines. Confocal laser scanning microscopy (CLSM was performed to obtain images of the distribution of CF in Caco-2 cells. These compounds were able to loosen tight junctions, thus increasing paracellular permeability. CLSM confirmed the effect of these absorption enhancers on CF transport across Caco-2 lines and increased the Caco-2 permeability via transcellular route. It was also confirmed that the decrease in TEER was transient and reversible after removal of permeation enhancers.

  20. Brush border membrane vesicle and Caco-2 cell line: Two experimental models for evaluation of absorption enhancing effects of saponins, bile salts, and some synthetic surfactants

    Science.gov (United States)

    Moghimipour, Eskandar; Tabassi, Sayyed Abolghassem Sajadi; Ramezani, Mohammad; Handali, Somayeh; Löbenberg, Raimar

    2016-01-01

    The aim of this study was to investigate the influence of absorption enhancers in the uptake of hydrophilic compounds. The permeation of the two hydrophilic drug models gentamicin and 5 (6)-carboxyfluorescein (CF) across the brush border membrane vesicles and Caco-2 cell lines were evaluated using total saponins of Acanthophyllum squarrosum, Quillaja saponaria, sodium lauryl sulfate, sodium glycocholate, sodium taurodeoxycholate, and Tween 20 as absorption enhancers. Transepithelial electrical resistance (TEER) measurement was utilized to assess the paracellular permeability of cell lines. Confocal laser scanning microscopy (CLSM) was performed to obtain images of the distribution of CF in Caco-2 cells. These compounds were able to loosen tight junctions, thus increasing paracellular permeability. CLSM confirmed the effect of these absorption enhancers on CF transport across Caco-2 lines and increased the Caco-2 permeability via transcellular route. It was also confirmed that the decrease in TEER was transient and reversible after removal of permeation enhancers. PMID:27429925

  1. Bacillus thuringiensis Cry1A toxin-binding glycoconjugates present on the brush border membrane and in the peritrophic membrane of the Douglas-fir tussock moth are peritrophins

    Science.gov (United States)

    Algimantas P. Valaitis; John D. Podgwaite

    2013-01-01

    Bacillus thuringiensis (Bt) Cry1A toxin-binding sites in the Douglas fir tussock moth (DFTM) larval gut were localized using immunofluorescence microscopy. Cry1Aa, Cry1Ab and Cry1Ac all bound strongly to the DFTM peritrophic membrane (PM); weaker binding of the Cry1A toxins was observed along the apical brush border of the midgut epithelium....

  2. Mechanism of cis- and trans-substrate interactions at the tetraethylammonium/H+ exchanger of rabbit renal brush-border membrane vesicles

    International Nuclear Information System (INIS)

    Wright, S.H.; Wunz, T.M.

    1988-01-01

    The kinetic basis for trans-effects of intravesicular substrates on the uptake of the organic cation, tetraethylammonium (TEA), into rabbit renal brush-border membrane vesicles (BBMV) was studied. Preloading BBMV with 1, 2, or 4 mM TEA stimulated the initial rate of uptake and the total net accumulation of 0.1 mM [ 3 H]TEA. The stimulatory effect of intravesicular TEA on the initial rate of uptake was a saturable function of the trans-TEA concentration, with a half-maximal effect noted at an intravesicular concentration of 0.28 mM. A 1 mM trans-concentration of TEA increased the Jmax of [ 3 H]TEA uptake (from 4.3 to 6.8 nmol.mg-1.min-1) without affecting the apparent Kt. An outwardly directed H+ gradient also increased Jmax (to 10.7 nmol.mg-1.min-1), although the addition of an outwardly directed TEA gradient did not produce further increases in the rate of TEA uptake. External H+ acted as a competitive inhibitor of TEA uptake, and an increase in external [H+] (from 32 nM to 100 nM) produced an increase in the apparent Kt for TEA transport (from 0.12 to 0.26 mM) without affecting the Jmax. The results suggested that TEA and H+ compete for a common site or set of mutually exclusive sites on the cytoplasmic and luminal aspects of TEA/H+ exchanger in the renal brush border, and that these sites have a similar affinity for TEA

  3. Experimental type II diabetes and related models of impaired glucose metabolism differentially regulate glucose transporters at the proximal tubule brush border membrane.

    Science.gov (United States)

    Chichger, Havovi; Cleasby, Mark E; Srai, Surjit K; Unwin, Robert J; Debnam, Edward S; Marks, Joanne

    2016-06-01

    What is the central question of this study? Although SGLT2 inhibitors represent a promising treatment for patients suffering from diabetic nephropathy, the influence of metabolic disruption on the expression and function of glucose transporters is largely unknown. What is the main finding and its importance? In vivo models of metabolic disruption (Goto-Kakizaki type II diabetic rat and junk-food diet) demonstrate increased expression of SGLT1, SGLT2 and GLUT2 in the proximal tubule brush border. In the type II diabetic model, this is accompanied by increased SGLT- and GLUT-mediated glucose uptake. A fasted model of metabolic disruption (high-fat diet) demonstrated increased GLUT2 expression only. The differential alterations of glucose transporters in response to varying metabolic stress offer insight into the therapeutic value of inhibitors. SGLT2 inhibitors are now in clinical use to reduce hyperglycaemia in type II diabetes. However, renal glucose reabsorption across the brush border membrane (BBM) is not completely understood in diabetes. Increased consumption of a Western diet is strongly linked to type II diabetes. This study aimed to investigate the adaptations that occur in renal glucose transporters in response to experimental models of diet-induced insulin resistance. The study used Goto-Kakizaki type II diabetic rats and normal rats rendered insulin resistant using junk-food or high-fat diets. Levels of protein kinase C-βI (PKC-βI), GLUT2, SGLT1 and SGLT2 were determined by Western blotting of purified renal BBM. GLUT- and SGLT-mediated d-[(3) H]glucose uptake by BBM vesicles was measured in the presence and absence of the SGLT inhibitor phlorizin. GLUT- and SGLT-mediated glucose transport was elevated in type II diabetic rats, accompanied by increased expression of GLUT2, its upstream regulator PKC-βI and SGLT1 protein. Junk-food and high-fat diet feeding also caused higher membrane expression of GLUT2 and its upstream regulator PKC

  4. Fermented soya bean (tempe) extracts reduce adhesion of enterotoxigenic Escherichia coli to intestinal epithelial cells

    NARCIS (Netherlands)

    Roubos-van den Hil, P.J.; Nout, M.J.R.; Beumer, R.R.; Meulen, van der J.; Zwietering, M.H.

    2009-01-01

    Aims: This study aimed to investigate the effect of processed soya bean, during the successive stages of tempe fermentation and different fermentation times, on adhesion of enterotoxigenic Escherichia coli (ETEC) K88 to intestinal brush border cells as well as Caco-2 intestinal epithelial cells; and

  5. VSL#3 Probiotic Upregulates Intestinal Mucosal Alkaline Sphingomyelinase and Reduces Inflammation

    Directory of Open Access Journals (Sweden)

    Isaac Soo

    2008-01-01

    Full Text Available BACKGROUND: Alkaline sphingomyelinase, an enzyme found exclusively in bile and the intestinal brush border, hydrolyzes sphingomyelin into ceramide, sphingosine and sphingosine-1-phosphate, thereby inducing epithelial apoptosis. Reduced levels of alkaline sphingomyelinase have been found in premalignant and malignant intestinal epithelia and in ulcerative colitis tissue. Probiotic bacteria can be a source of sphingomyelinase.

  6. Interaction of Lysinibacillus sphaericus Cry48Aa/Cry49Aa toxin with midgut brush-border membrane fractions from Culex quinquefasciatus larvae.

    Science.gov (United States)

    Guo, Q-Y; Hu, X-M; Cai, Q-X; Yan, J-P; Yuan, Z-M

    2016-04-01

    The Cry48Aa/Cry49Aa mosquitocidal toxin from Lysinibacillus sphaericus was uniquely composed of a three-domain (Cry) toxin and binary (Bin) toxin-like protein, with high toxicity against Culex spp. However, its mode of action against the target mosquitoes is still unknown. In this study, Cry48Aa, Cry49Aa and its N- and C-terminal truncated proteins were expressed and purified, and the binding affinities of the purified proteins with midgut brush-border membrane fractions (BBMFs) from Culex quin-quefasciatus larvae were performed. The results showed that both Cry48Aa and Cry49Aa have specific and high binding affinity to BBMFs, with dissociation constants of 9.5 ± 1.8 and 25.4 ± 3.8 nM, respectively. Competition assays demonstrated that Cry49Aa C-terminal derivatives were able to bind to the BBMFs, whereas Far-Western dot blot analysis revealed that its N-terminal constructs interacted with Cry48Aa. Nevertheless, larvicidal activity was almost lost when Cry49Aa truncated proteins, either individually or in pairs, combined with Cry48Aa. It is concluded that Cry49Aa is responsible for receptor binding and interaction with Cry48Aa and plays an important role in the mechanism of action of these two-component toxins. © 2016 The Royal Entomological Society.

  7. Comparative Proteomic Analysis of the Effect of Periplocoside P from Periploca sepium on Brush Border Membrane Vesicles in Midgut Epithelium of Mythimna separata Larvae

    Directory of Open Access Journals (Sweden)

    Mingxing Feng

    2017-12-01

    Full Text Available Periplocoside P (PSP, a novel compound isolated from Periploca sepium Bunge, possesses insecticidal activity against some lepidopterans, such as Mythimna separata. In M. separata, the brush border membrane vesicles of the midgut epithelium are the initial site of action of periplocosides. We conducted two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time of flight/time of flight mass spectrometry analysis to analyze differentially expressed proteins (DEPs from periplocoside P (PSP-treated M. separata. We successfully isolated seven up-regulated and three down-regulated DEPs that have been previously identified, as well as a novel DEP. The DEPs are implicated in protein degradation, transporter, folding, and synthesis, and in juvenile hormone biosynthesis. DEPs involved in the oxidative phosphorylation energy metabolism pathway are enriched. Through real-time polymerase chain reaction assay, we confirmed that vma1 expression is significantly up-regulated expression levels in PSP-treated M. separata larvae. Enzymology validation further indicated that PSP can significantly inhibit V-type ATPase activity in a concentration-dependent manner. Given these results, we speculate that in M. separata, the V-type ATPase A subunit in the midgut epithelium is the putative target binding site of periplocosides. This finding provides preliminary evidence for the mode of action of periplocosides.

  8. Studies on the effect of sodium arsenate on the enzymes of carbohydrate metabolism, brush border membrane, and oxidative stress in the rat kidney.

    Science.gov (United States)

    Shahid, Faaiza; Rizwan, Sana; Khan, Md Wasim; Khan, Sara Anees; Naqshbandi, Ashreeb; Yusufi, Ahad Noor Khan

    2014-03-01

    Arsenic is an environmental pollutant and its contamination in drinking water poses serious world wide environmental health threats. It produces multiple adverse effects in various tissues, including the kidney. However, biochemical mechanism and renal response to its toxic insult are not completely elucidated. We hypothesized that sodium arsenate (ARS) induces oxidative stress and alters the structure and metabolic functions of kidney. Male Wistar rats were administered ARS (10 mg/kg body weight/day), intraperitoneally daily for 10 days. ARS administration increased blood urea nitrogen, serum creatinine, cholesterol, glucose, and phospholipids but decreased inorganic phosphate, indicating kidney toxicity. The activity of brush border membrane (BBM) enzymes significantly lowered in both cortex and medulla. Activity of hexokinase, lactate dehydrogenase, glucose-6-phosphate dehydrogenases, and NADP-malic enzyme significantly increased whereas malate dehydrogenase, glucose-6-phosphatase, and fructose 1,6 bis phosphatase decreased by ARS exposure. The activity of superoxide dismutase, GSH-peroxidase, and catalase were selectively altered in renal tissues along with an increase in lipid peroxidation. The present results indicated that ARS induced oxidative stress caused severe renal damage that resulted in altered levels of carbohydrate metabolism and BBM enzymes. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Comparative Proteomic Analysis of the Effect of Periplocoside P from Periploca sepium on Brush Border Membrane Vesicles in Midgut Epithelium of Mythimna separata Larvae.

    Science.gov (United States)

    Feng, Mingxing; Li, Yankai; Chen, Xueting; Wei, Quansheng; Wu, Wenjun; Hu, Zhaonong

    2017-12-22

    Periplocoside P (PSP), a novel compound isolated from Periploca sepium Bunge, possesses insecticidal activity against some lepidopterans, such as Mythimna separata . In M. separata, the brush border membrane vesicles of the midgut epithelium are the initial site of action of periplocosides. We conducted two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time of flight/time of flight mass spectrometry analysis to analyze differentially expressed proteins (DEPs) from periplocoside P (PSP)-treated M. separata . We successfully isolated seven up-regulated and three down-regulated DEPs that have been previously identified, as well as a novel DEP. The DEPs are implicated in protein degradation, transporter, folding, and synthesis, and in juvenile hormone biosynthesis. DEPs involved in the oxidative phosphorylation energy metabolism pathway are enriched. Through real-time polymerase chain reaction assay, we confirmed that vma1 expression is significantly up-regulated expression levels in PSP-treated M. separata larvae. Enzymology validation further indicated that PSP can significantly inhibit V-type ATPase activity in a concentration-dependent manner. Given these results, we speculate that in M. separata , the V-type ATPase A subunit in the midgut epithelium is the putative target binding site of periplocosides. This finding provides preliminary evidence for the mode of action of periplocosides.

  10. Oral thymoquinone administration ameliorates: the effect of cisplatin on brush border membrane enzymes, energy metabolism, and redox status in rat kidney.

    Science.gov (United States)

    Farooqui, Zeba; Shahid, Faaiza; Abidi, Subuhi; Parwez, Iqbal; Khan, Farah

    2017-12-01

    Therapeutic use of cisplatin (CP), an effective anticancer drug, is limited by dose dependent nephrotoxicity. Thymoquinone (TQ), the major Nigella sativa seed oil constituent has been shown to prevent progression of various renal disorders. The present study investigates the protective effect of TQ on CP-induced nephrotoxicity. Rats were divided into six groups viz. control, CP, CPTQ 1 , CPTQ 2 , CPTQ 3 , and TQ alone group. Animals in CP and TQ combination groups were administered TQ (0.5, 1.5, and 3 mg/kg bwt, orally) with single intraperitoneal dose of CP (6 mg/kg bwt). The effect of TQ administration was determined on CP-induced alterations in various serum/urine parameters and on the enzymes of brush border membrane enzyme (BBM), carbohydrate metabolism, and antioxidant defense system in renal cortex and medulla. Oral administration of TQ in all the three doses prior to and following a single dose CP treatment caused significant recovery of serum creatinine and blood urea nitrogen levels; however, maximum recovery was seen in CPTQ 2 group. TQ administration averted CP-induced decline in BBM activities, both in the cortical and medullary homogenates and in isolated BBM vesicles. TQ administration also ameliorated CP-induced impairments in renal metabolic and antioxidant status. Histopathological studies supported these biochemical findings. TQ ameliorates CP-induced oxidative damage owing to its intrinsic antioxidant properties.

  11. Dietary flaxseed oil supplementation mitigates the effect of lead on the enzymes of carbohydrate metabolism, brush border membrane, and oxidative stress in rat kidney tissues.

    Science.gov (United States)

    Rizwan, Sana; Naqshbandi, Ashreeb; Khan, Farah

    2013-06-01

    Lead is a heavy metal widely distributed in the environment. Lead is a ubiquitous environmental toxin that is capable of causing numerous acute and chronic illnesses. Human and animal exposure demonstrates that lead is nephrotoxic. However, attempts to reduce lead-induced nephrotoxicity were not found suitable for clinical use. Recently, flaxseed oil (FXO), a rich source of ω-3 fatty acids and lignans, has been shown to prevent/reduce the progression of certain types of cardiovascular and renal disorders. In view of this, the present study investigates the protective effect of FXO on lead acetate (PbAc)-induced renal damage. Rats were pre-fed normal diet and the diet rich in FXO for 14 days, and then, four doses of lead acetate (25 mg/kg body weight) were administered intraperitoneally while still on diet. Various serum parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), and oxidative stress were analyzed in rat kidney. PbAc nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. PbAc increased the activities of lactate dehydrogenase and NADP-malic enzyme, whereas it decreased malate and glucose-6-phosphate dehydrogenase, glucose-6-phosphatase, fructose-1, 6-bisphosphatase, and BBM enzyme activities. PbAc caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation and decreased activities of superoxide dismutase, glutathione peroxidase, and catalase. In contrast, FXO alone enhanced the enzyme activities of carbohydrate metabolism, BBM, and antioxidant defense system. FXO feeding to PbAc-treated rats markedly enhanced resistance to PbAc-elicited deleterious effects. In conclusion, dietary FXO supplementation ameliorated PbAc-induced specific metabolic alterations and oxidative damage by empowering antioxidant defense mechanism and improving BBM integrity and energy metabolism.

  12. Endocrine regulation of ion transport in the avian lower intestine

    DEFF Research Database (Denmark)

    Laverty, Gary; Elbrønd, Vibeke Sødring; Árnason, Sighvatur S.

    2006-01-01

    The lower intestine (colon and coprodeum) of the domestic fowl maintains a very active, transporting epithelium, with a microvillus brush border, columnar epithelial cells, and a variety of transport systems. The colon of normal or high salt-acclimated hens expresses sodium-linked glucose and amino...

  13. Adaptation of intestinal hydrolases to starvation in rats: effect of thyroid function

    DEFF Research Database (Denmark)

    Galluser, M; Belkhou, R; Freund, J N

    1991-01-01

    this process. These results indicate that intestinal hydrolases respond non-coordinately to long-term food deprivation. In addition, the thyroid status of the animals has a direct influence on the adaptation of several brush border hydrolases to starvation. This suggests that the drop in plasma thyroid...... hormones during fasting allows a better maintenance of protein content and of hydrolase activities in the brush border membranes of the small intestine. These adaptive processes seemed to be partly controlled at a post-transcriptional level....

  14. Interactions of [14C]phosphonoformic acid with renal cortical brush-border membranes. Relationship to the Na+-phosphate co-transporter

    International Nuclear Information System (INIS)

    Szczepanska-Konkel, M.; Yusufi, A.N.; Dousa, T.P.

    1987-01-01

    Since phosphonoformic acid (PFA) acts as a specific competitive inhibitor of Na+-Pi co-transport across renal brush-border membrane (BBM), we employed the [ 14 C]PFA as a probe to determine the mechanism of its interaction with rat renal BBM. The binding of [ 14 C]PFA to BBM vesicles (BBMV), with Na+ present in extravesicular medium (Na+o), was time- and temperature-dependent. The replacement of Na+o with other monovalent cations reduced the PFA binding by -80%. Cl- was the most effective accompanying monovalent anion as NaCl for maximum PFA binding. The Na+o increased the apparent affinity of BBMV for [ 14 C]PFA binding, but it did not change the maximum binding capacity. The maximum [ 14 C]PFA binding was achieved at Na+o approximately equal to 50 mM. The extent of Na+-dependent [ 14 C]PFA binding correlated with percent inhibition by an equimolar dose of PFA of the dependent BBMV uptake of 32Pi. Intravesicular Na+ (Na+i) decreased [ 14 C]PFA binding, on BBMV, and this inhibition by Na+i was dependent on the presence of Na+o. The increase in Na+i, at constant [Na+]o, decreased the Vmax, but not the Km, for [ 14 C]PFA binding on BBMV. Bound [ 14 C]PFA was displaced from BBMV by phosphonocarboxylic acids proportionally to their ability to inhibit gradient-dependent Pi transport, whereas other monophosphonates, diphosphonates, L-proline, or D-glucose did not influence the [ 14 C]PFA binding. The Na+-dependent binding of [ 14 C]PFA and of [ 3 H]phlorizin by BBMV was 10 times higher than binding of these ligands to renal basolateral membranes and to mitochondria. [ 14 C]PFA probably binds onto the same locus on the luminal surface of BBM, where Pi and Na+ form a ternary complex with the Na+-Pi co-transporter

  15. Bovine colostrum improves intestinal function following formula-induced gut inflammation in preterm pigs

    DEFF Research Database (Denmark)

    Støy, Ann Cathrine Findal; Heegaard, Peter M. H.; Thymann, Thomas

    2014-01-01

    , abundance and location of bacteria, and inflammation markers were investigated. Results NEC severity and interleukins (IL)-1β and -8 protein concentrations were lower, while villus height, galactose absorption, and brush-border enzyme activities were increased in the distal small intestine in COLOS...

  16. Proper Brushing

    Science.gov (United States)

    ... both the tooth surface and the gumline. Gently brush the outer tooth surfaces of 2-3 teeth using a vibrating ... along all of the inner tooth surfaces. Tilt brush vertically behind the front teeth. Make several up & down strokes using the front ...

  17. Experimental type II diabetes and related models of impaired glucose metabolism differentially regulate glucose transporters at the proximal tubule brush border membrane

    OpenAIRE

    Chichger, H.; Cleasby, M.; Srai, S.; Unwin, R.; Debnam, E.; Marks, J.

    2016-01-01

    What is the central question of this study? Although SGLT2 inhibitors represent a promising treatment for patients suffering from diabetic nephropathy, the influence of metabolic disruption on the expression and function of glucose transporters is largely unknown. What is the main finding and its importance? In vivo models of metabolic disruption (Goto-Kakizaki type II diabetic rat and junk-food diet) demonstrate increased expression of SGLT1, SGLT2 and GLUT2 in the proximal tubule brush bord...

  18. Regulation of the epithelial Ca2+ channels in small intestine as studied by quantitative mRNA detection.

    NARCIS (Netherlands)

    Abel, M. van; Hoenderop, J.G.J.; Kemp, J.W.C.M. van der; Leeuwen, J.P.P.M. van; Bindels, R.J.M.

    2003-01-01

    The epithelial Ca2+ channels TRPV5 and TRPV6 are localized to the brush border membrane of intestinal cells and constitute the postulated rate-limiting entry step of active Ca2+ absorption. The aim of the present study was to investigate the hormonal regulation of these channels. To this end, the

  19. Allergic sensitization to ovalbumin in mouse model of food allergy is accompanied by stimulation of enterocyte brush border alkaline phosphatase activity

    Czech Academy of Sciences Publication Activity Database

    Schwarzer, Martin; Kozáková, Hana; Goliáš, Jaroslav; Kverka, Miloslav; Cinová, Jana; Rossmann, Pavel; Tučková, Ludmila

    2012-01-01

    Roč. 6, č. 1 (2012), s. 53-53 ISSN 1555-8932. [Meeting of the European Intestinal Transport Group /24./. 04.09.2012-07.09.2012, Oxford] R&D Projects: GA AV ČR IAA500200913 Institutional research plan: CEZ:AV0Z50200510 Keywords : ovalbumin * allergy Subject RIV: EC - Immunology

  20. Morphological data indicate a stress response at the oral border of strangulated small intestine in horses.

    Science.gov (United States)

    De Ceulaer, K; Delesalle, C; Van Elzen, R; Van Brantegem, L; Weyns, A; Van Ginneken, C

    2011-10-01

    Strangulation colic often leads to surgery. We aimed to document the molecular response in the non-resected intestine in these horses using quantitative Western blot analysis, and immunohistochemistry. The expression of hypoxia-inducible factor 1-alpha (HIF1α) was investigated together with two molecular pathways initiated after protein destruction: proteasome degradation via ubiquitin chain formation and protein restoration via molecular chaperones such as inducible heat shock protein 70 (HSP70). In addition, the expression of c-fos and c-jun could indicate an early proinflammatory response. Ubiquitin, HSP70, c-jun and c-fos protein levels did not differ between the control and colic samples nor were they related to the clinical outcome in case of strangulation colic. However, the immunohistochemical distribution of several of these proteins (ubiquitin, HSP70 and c-jun) differed significantly between colic and control samples. The elevated presence of ubiquitin in the enterocytes' nucleus, of HSP70 in the smooth muscle cells' nucleus and of c-jun in enteric neurons suggest protective and degenerative pathways are activated in the apparently healthy non-resected tissue in case of strangulation obstruction, perhaps providing a molecular and morphological basis for the development of complications like post-operative ileus. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Colonization of germ-free piglets with probiotic E. coli is associated with stimulated production of TNF-alpha and acceleration of brush border enzyme and glycoconjugate development

    Czech Academy of Sciences Publication Activity Database

    Kozáková, Hana; Kolínská, Jiřina; Zákostelecká, Marie; Lojda, Z.

    2005-01-01

    Roč. 17, č. 4 (2005), s. 231-232 ISSN 0891-060X. [Gnotobiology symposium. 20.06.2005-24.06.2005, Tokio] R&D Projects: GA ČR(CZ) GA303/05/2249 Institutional research plan: CEZ:AV0Z50200510; CEZ:AV0Z50110509 Keywords : swine miniature * enterocyte * Escherichia coli * small intestine Subject RIV: EC - Immunology

  2. Human intestinal maltase-glucoamylase: crystal structure of the N-terminal catalytic subunit and basis of inhibition and substrate specificity

    Science.gov (United States)

    Human maltase-glucoamylase (MGAM) is one of the two enzymes responsible for catalyzing the last glucose-releasing step in starch digestion. MGAM is anchored to the small-intestinal brush-border epithelial cells and contains two homologous glycosyl hydrolase family 31 catalytic subunits: an N-termina...

  3. Intestinal surfactant permeation enhancers and their interaction with enterocyte cell membranes in a mucosal explant system

    DEFF Research Database (Denmark)

    Danielsen, E Michael; Hansen, Gert H

    2017-01-01

    Intestinal permeation enhancers (PEs) are agents aimed to improve oral delivery of therapeutic drugs with poor bioavailability. The main permeability barrier for oral delivery is the intestinal epithelium, and PEs act to increase the paracellular and/or transcellular passage of drugs. Transcellular....... In the present work, the interaction of the surfactants lauroyl-L-carnitine, 1-decanoyl-rac-glycerol, and nonaethylene glycol monododecyl ether with the intestinal epithelium was studied in organ cultured pig jejunal mucosal explants. As expected, at 2 mM, these agents rapidly permeabilized the enterocytes...... for the fluorescent polar tracer lucifer yellow, but surprisingly, they all also blocked both constitutive -and receptor-mediated pathways of endocytosis from the brush border, indicating a complete arrest of apical membrane trafficking. At the ultrastructural level, the PEs caused longitudinal fusion of brush border...

  4. Regulation of intestinal calcium absorption by luminal calcium content: role of intestinal alkaline phosphatase.

    Science.gov (United States)

    Brun, Lucas R; Brance, María L; Lombarte, Mercedes; Lupo, Maela; Di Loreto, Verónica E; Rigalli, Alfredo

    2014-07-01

    Intestinal alkaline phosphatase is a brush border enzyme that is stimulated by calcium. Inhibition of intestinal alkaline phosphatase increases intestinal calcium absorption. We hypothesized that intestinal alkaline phosphatase acts as a minute-to-minute regulatory mechanism of calcium entry. The aim of this study was to evaluate the mechanism by which intestinal luminal calcium controls intestinal calcium absorption. We performed kinetic studies with purified intestinal alkaline phosphatase and everted duodenal sacs and showed that intestinal alkaline phosphatase modifies the luminal pH as a function of enzyme concentration and calcium luminal content. A decrease in pH occurred simultaneously with a decrease in calcium absorption. The inhibition of intestinal alkaline phosphatase by l-phenylalanine caused an increase in calcium absorption. This effect was also confirmed in calcium uptake experiments with isolated duodenal cells. Changes in luminal pH arising from intestinal alkaline phosphatase activity induced by luminal calcium concentration modulate intestinal calcium absorption. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Adaptation of intestinal hydrolases to starvation in rats: effect of thyroid function

    DEFF Research Database (Denmark)

    Galluser, M; Belkhou, R; Freund, J N

    1991-01-01

    The effects of long-term starvation on the activities of sucrase, lactase, and aminopeptidase, and on their respective mRNA were determined in the small intestine of thyroidectomized and sham-operated adult rats. Thyroidectomy reduced the protein loss at the level of the intestinal brush border...... membranes during starvation. Prolonged fasting caused a significant decrease in sucrase activity, but thyroidectomy partly prevented this effect. However, the amount of the corresponding mRNA dropped during long term starvation without incidence of thyroidectomy. Lactase activity in the brush border...... membranes was increased by starvation, and thyroidectomy caused a further elevation of the enzyme activity. Simultaneously, lactase mRNA content rose only slightly compared to the enzyme activity. Aminopeptidase activity and mRNA content decreased during starvation and thyroidectomy did not prevent...

  6. Characterization of Mucosal Disaccharidases from Human Intestine

    Directory of Open Access Journals (Sweden)

    Mahdi Amiri

    2017-10-01

    Full Text Available In this study, we used a brush border membrane (BBM preparation from human small intestine to analyze the proportion and the activity of major intestinal disaccharidases, including sucrase-isomaltase (SI, maltase-glucoamylase (MGAM and lactase-phlorizin hydrolase (LPH. SI, MGAM and LPH respectively constituted 8.2%, 2.7% and 1.4% of total BBM protein. The activity of SI and LPH decreased threefold after purification from the brush border membrane, which highlights the effect of membrane microdomains on the functional capacity of these enzymes. All of the disaccharidases showed optimal activity at pH 6, over 50% residual activity between pH 5 to pH 7, and increasing activity with rising temperatures up to 45 °C, along with a stable functional structure. Therefore the enzymes can withstand mild intraluminal pH alterations with adequate function, and are able to increase their activity with elevated core body temperature. Our data provide a functional measure for characterization of intestinal disaccharidases under different physiological and pathological conditions.

  7. Brush border enzyme activities in the small intestine after long-term gliadin feeding in animal models of human coeliac disease

    Czech Academy of Sciences Publication Activity Database

    Kozáková, M.; Štěpánková, R.; Kolínská, Jiřina; Farré Castany, M.; Funda, D. P.; Tučková, L.; Tlaskalová-Hogenová, H.

    1998-01-01

    Roč. 43, č. 5 (1998), s. 497-500 ISSN 0015-5632 R&D Projects: GA ČR GA303/96/1256; GA ČR GA311/97/0784; GA ČR GA310/96/1366; GA AV ČR IAA7020716; GA MZd IZ4150; GA MZd IZ3761 Subject RIV: ED - Physiology Impact factor: 0.518, year: 1998

  8. Postnatal ontogeny of intestinal GCPII and the RFC in pig.

    Science.gov (United States)

    Shafizadeh, Tracy B; Halsted, Charles H

    2009-03-01

    In humans and pigs, hydrolysis of dietary polyglutamyl folates is carried out by intestinal brush border folate hydrolase [glutamate carboxypeptidase II (GCPII)], whereas the transport of the monoglutamyl folate derivatives occurs via the intestinal brush border reduced folate carrier (RFC). The study objective was to measure the expression of intestinal GCPII and RFC during postnatal development of pigs and their effects on plasma and liver folate concentrations. Duodenum, jejunum, ileum, liver, and plasma samples were collected from female Yorkshire pigs at birth, 24 h, 1 wk, 3 wk, and 6 mo (n=6 at each time point). GCPII mRNA transcripts and protein (normalized using beta-actin), and enzyme activity (normalized per mg mucosal protein) were highest in all segments of small intestine at birth and were undetectable in ileum after 1 wk, whereas jejunal protein and activity predominated at 6 mo. RFC mRNA transcripts were present in all segments of small intestine at birth and declined significantly throughout development to 6 mo. Conversely, RFC protein increased twofold during the first 24 h and remained constant throughout development in all segments of small intestine. Liver RFC mRNA transcripts were detected at birth but were reduced by 6 mo. Liver folate concentration increased throughout postnatal development, whereas plasma folate levels increased during the first 24 h but decreased over time, reflecting the pattern of RFC expression in small intestine. These findings show that intestinal GCPII and intestinal and hepatic RFC all exhibit ontogenic changes in the pig that are reflected in postnatal folate status.

  9. The intestinal calcistat

    Directory of Open Access Journals (Sweden)

    M K Garg

    2013-01-01

    Full Text Available The main physiological function of vitamin D is maintenance of calcium homeostasis by its effect on calcium absorption, and bone health in association with parathyroid gland. Vitamin D deficiency (VDD is defined as serum 25-hydroxy vitamin D (25OHD levels <20 ng/ml. Do all subjects with VDD have clinical disease according to this definition? We hypothesize that there exist an intestinal calcistat, which controls the calcium absorption independent of PTH levels. It consists of calcium sensing receptor (CaSR on intestinal brush border, which senses calcium in intestinal cells and vitamin D system in intestinal cells. CaSR dampens the generation of active vitamin D metabolite in intestinal cells and decrease active transcellular calcium transport. It also facilitates passive paracellular diffusion of calcium in intestine. This local adaptation adjusts the fractional calcium absorption according the body requirement. Failure of local adaptation due to decreased calcium intake, decreased supply of 25OHD, mutation in CaSR or vitamin D system decreases systemic calcium levels and systemic adaptations comes into the play. Systemic adaptations consist of rise in PTH and increase in active vitamin D metabolites. These adaptations lead to bone resorption and maintenance of calcium homeostasis. Not all subjects with varying levels of VDD manifest with secondary hyperparathyroidism and decreased in bone mineral density. We suggest that rise in PTH is first indicator of VDD along with decrease in BMD depending on duration of VDD. Hence, subjects with any degree of VDD with normal PTH and BMD should not be labeled as vitamin D deficient. These subjects can be called subclinical VDD, and further studies are required to assess beneficial effect of vitamin D supplementation in this subset of population.

  10. Brushes and proteins

    NARCIS (Netherlands)

    Bosker, W.T.E.

    2011-01-01

      Brushes and Proteins   Wouter T. E. Bosker         Protein adsorption at solid surfaces can be prevented by applying a polymer brush at the surface. A polymer brush consists of polymer chains end-grafted to the surface at such a grafting density that

  11. Compartmentalised expression of meprin in small intestinal mucosa: enhanced expression in lamina propria in coeliac disease.

    Science.gov (United States)

    Lottaz, Daniel; Buri, Caroline; Monteleone, Giovanni; Rösmann, Sandra; Macdonald, Thomas T; Sanderson, Ian R; Sterchi, Erwin E

    2007-03-01

    Epithelial cells in the human small intestine express meprin, an astacin-like metalloprotease, which accumulates normally at the brush border membrane and in the gut lumen. Therefore, meprin is targeted towards luminal components. In coeliac disease patients, peptides from ingested cereals trigger mucosal inflammation in the small intestine, disrupting epithelial cell differentiation and function. Using in situ hybridisation on duodenal tissue sections, we observed a marked shift of meprin mRNA expression from epithelial cells, the predominant expression site in normal mucosa, to lamina propria leukocytes in coeliac disease. Meprin thereby gains access to the substrate repertoire present beneath the epithelium.

  12. Biosynthesis of intestinal microvillar proteins. Dimerization of aminopeptidase N and lactase-phlorizin hydrolase

    DEFF Research Database (Denmark)

    Danielsen, E M

    1990-01-01

    of dimers of this enzyme therefore occurs prior to the Golgi-associated processing, and the slow rate of dimerization may be the rate-limiting step in the transport from the endoplasmic reticulum to the Golgi complex. For lactase-phlorizin hydrolase, the posttranslational processing includes a proteolytic......The pig intestinal brush border enzymes aminopeptidase N (EC 3.4.11.2) and lactase-phlorizin hydrolase (EC 3.2.1.23-62) are present in the microvillar membrane as homodimers. Dimethyl adipimidate was used to cross-link the two [35S]methionine-labeled brush border enzymes from cultured mucosal...... explants. For aminopeptidase N, dimerization did not begin until 5-10 min after synthesis, and maximal dimerization by cross-linking of the transient form of the enzyme required 1 h, whereas the mature form of aminopeptidase N cross-linked with unchanged efficiency from 45 min to 3 h of labeling. Formation...

  13. Fermented soya bean (tempe) extracts reduce adhesion of enterotoxigenic Escherichia coli to intestinal epithelial cells.

    Science.gov (United States)

    Roubos-van den Hil, P J; Nout, M J R; Beumer, R R; van der Meulen, J; Zwietering, M H

    2009-03-01

    This study aimed to investigate the effect of processed soya bean, during the successive stages of tempe fermentation and different fermentation times, on adhesion of enterotoxigenic Escherichia coli (ETEC) K88 to intestinal brush border cells as well as Caco-2 intestinal epithelial cells; and to clarify the mechanism of action. Tempe was prepared at controlled laboratory scale using Rhizopus microsporus var. microsporus as the inoculum. Extracts of raw, soaked and cooked soya beans reduced ETEC adhesion to brush border cells by 40%. Tempe extracts reduced adhesion by 80% or more. ETEC adhesion to Caco-2 cells reduced by 50% in the presence of tempe extracts. ETEC K88 bacteria were found to interact with soya bean extracts, and this may contribute to the observed decrease of ETEC adhesion to intestinal epithelial cells. Fermented soya beans (tempe) reduce the adhesion of ETEC to intestinal epithelial cells of pig and human origin. This reduced adhesion is caused by an interaction between ETEC K88 bacteria and soya bean compounds. The results strengthen previous observations on the anti-diarrhoeal effect of tempe. This effect indicates that soya-derived compounds may reduce adhesion of ETEC to intestinal cells in pigs as well as in humans and prevent against diarrhoeal diseases.

  14. Lactoferrin targets T cells in the small intestine

    DEFF Research Database (Denmark)

    Nielsen, Sanne Mie; Hansen, Gert Helge; Danielsen, E Michael

    2010-01-01

    BACKGROUND: Lactoferrin (Lf) belongs to the transferrin family of non-heme iron-binding proteins and is found in milk and mucosal secretions. Consequently, it is now considered a multifunctional protein mainly involved in both the innate and adaptive immune defenses of the organism against various...... explants of pig small intestine by immunofluorescence and immunogold microscopy. RESULTS: Lf rapidly bound to the brush border and subsequently appeared in punctae in the apical cytoplasm, indicating internalization into an endosomal compartment. Essentially, no labeling was detected elsewhere...

  15. Dermabrasion by wire brush.

    Science.gov (United States)

    Yarborough, J M

    1987-06-01

    While many physicians choose the fraise for all dermabrasive surgery, others prefer the faster abrasiveness and reduced friction of the brush for deep full-faced abrasions, removal of tattoos, and revision of scars. In addition to preoperative preparation and postoperative care of the patient, the author's technique for full-face abrasion with the power-driven rotary brush is described.

  16. [Analysis of the biorhythm frequency of bordered enterocytes during normal and inverted feeding regimens].

    Science.gov (United States)

    Liashko, O G

    1977-10-01

    The study was performed during the period close to equinox in 236 male mice C57 Bl strain, sacrificed at equal intervals during 5 days. In paraffin sections, 5--6 mcm thick, stained after Dominici-Kedrovsky, with additional application of PAS-reaction and alcian blue, the cell height and width in the small intestine border enterocyte zone were determined. Calculation of autocorrelative function with the following determination of spectral density, infradian, circadian and ultradian biorhythmical components were estimated, as well as their changes under the influence of feeding regime inversion. At evening feeding, the greatest width of the brush border coinsides the beginning and the end of the digestion period. The width of the dark apical zone, where mitochondria are concentrated, synchronously changes at the end of digestion with the brush border, and then- with the cell basal zone. At morning feeding, by the degree of circadian phase change, the most liable are the indices reflecting organoid status, which are closely involved in absorbtion processes. Ultradian rhythm produces, on the background of circadian changes, additional raisis and abatements. Spectral composition, under inadequate feeding, is demonstrated to become more complex, mainly at the expense of ultradian rhythms, that speaks of their importance for the processes of adaptive rhythmical rearrangement.

  17. Further characterization of intestinal lactase/phlorizin hydrolase

    DEFF Research Database (Denmark)

    Skovbjerg, H; Norén, O; Sjöström, H

    1982-01-01

    Pig intestinal lactase/phlorizin hydrolase (EC 3.2.1.23/62) was purified in its amphiphilic form by immunoadsorbent chromatography. The purified enzyme was free of other known brush border enzymes and appeared homogeneous in immunoelectrophoresis and polyacrylamide gel electrophoresis in the pres......Pig intestinal lactase/phlorizin hydrolase (EC 3.2.1.23/62) was purified in its amphiphilic form by immunoadsorbent chromatography. The purified enzyme was free of other known brush border enzymes and appeared homogeneous in immunoelectrophoresis and polyacrylamide gel electrophoresis...... in the presence of SDS. Pig lactase/phlorizin hydrolase was shown to have the same quaternary structure as the human enzyme, i.e., built up of two polypeptides of the same molecular weight (160000). In addition to hydrolyzing lactose, phlorizin and a number of synthetic substrates, both the human and the pig...... enzyme were shown to have a considerable activity against cellotriose and cellotetraose, and a low but significant activity against cellulose. The lactase/phlorizin hydrolase isolated from pigs in which the pancreatic ducts had been disconnected 3 days before death and from Ca2+-precipitated enterocyte...

  18. Biosynthesis of intestinal microvillar proteins. Dimerization of aminopeptidase N and lactase-phlorizin hydrolase

    Energy Technology Data Exchange (ETDEWEB)

    Danielsen, E.M. (Univ. of Cophenhagen (Denmark))

    1990-01-09

    The pig intestinal brush border enzymes aminopeptidase and lactase-phlorizin hydrolase are present in the microvilla membrane as homodimers. Dimethyl adipimidate was used to cross-link the two ({sup 35}S)methionine-labeled brush border enzymes from cultured mucosal explants. For aminopeptidase N, dimerization did not begin until 5-10 min after synthesis, and maximal dimerization by cross-linking of the transient form of the enzyme required 1 h, whereas the mature form of aminopeptidase N cross-linked with unchanged efficiency from 45 min to 3 h of labeling. Formation of dimers of this enzyme therefore occurs prior to the Golgi-associated processing, and the slow rate of dimerization may be the rate-limiting step in the transport from the endoplasmic reticulum to the Golgi complex. For lactase-phlorizin hydrolase, the posttranslational processing includes a proteolytic cleavage of its high molecular weight precursor. Since only the mature form and not the precursor of this enzyme could be cross-linked, formation of tightly associated dimers only takes place after transport out of the endoplasmic reticulum. Dimerization of the two brush border enzymes therefore seems to occur in different organelles of the enterocyte.

  19. Trafficking Ion Transporters to the Apical Membrane of Polarized Intestinal Enterocytes.

    Science.gov (United States)

    Engevik, Amy Christine; Goldenring, James R

    2018-01-02

    Epithelial cells lining the gastrointestinal tract require distinct apical and basolateral domains to function properly. Trafficking and insertion of enzymes and transporters into the apical brush border of intestinal epithelial cells is essential for effective digestion and absorption of nutrients. Specific critical ion transporters are delivered to the apical brush border to facilitate fluid and electrolyte uptake. Maintenance of these apical transporters requires both targeted delivery and regulated membrane recycling. Examination of altered apical trafficking in patients with Microvillus Inclusion disease caused by inactivating mutations in MYO5B has led to insights into the regulation of apical trafficking by elements of the apical recycling system. Modeling of MYO5B loss in cell culture and animal models has led to recognition of Rab11a and Rab8a as critical regulators of apical brush border function. All of these studies show the importance of apical membrane trafficking dynamics in maintenance of polarized epithelial cell function. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  20. Application of a pig ligated intestinal loop model for early Lawsonia intracellularis infection

    DEFF Research Database (Denmark)

    Boutrup, Torsten Snogdal; Schauser, Kirsten; Agerholm, Jørgen S

    2010-01-01

    (Enterisol® Ileitis Vet), and 3) vaccine bacteria propagated in cell culture. The bacteria-enterocyte interaction was visualised using immunohistochemistry on specimens derived 1, 3 and 6 h PI respectively. Results Although at a low level, close contact between bacteria and the enterocyte brush border...... including intracellular uptake of bacteria in mature enterocytes was seen at 3 and 6 h PI for the vaccine and the propagated vaccine inocula. Interaction between the wild-type bacteria and villus enterocytes was scarce and only seen at 6 h PI, where a few bacteria were found in close contact with the brush...... and that the bacterium, as shown for the vaccine bacteria, propagated as well as non-propagated, was able to invade mature enterocytes. Thus, the study demonstrates the early intestinal invasion of L. intracellularis in vivo....

  1. Alterations of intestinal glycoprotein hydrolases in congenital diabetes

    Energy Technology Data Exchange (ETDEWEB)

    Najjar, S.M.

    1989-01-01

    The diabetic BioBreed (BB{sub d}) rat was used for the study of the molecular structure of intestinal brush border sucrase-{alpha}-dextrinase (SD) and aminooligopeptidase (AOP) in diabetes mellitus. The specific catalytic activity of S-D and AOP in the BB{sub d} rat is normal. However, solid-phase radioimmunoassay revealed loss of some antigenic determinants in the BB{sub d} rat. S-D and AOP migrated abnormally on 6% SDS-gel electrophoresis in the BB{sub d} rat. S was larger (+5 kDa), D was either smaller (-5 kDa) or unaltered, and AOP was smaller (-5 kDa) in the BB{sub d} than in the normal Wistar. The structural abnormalities were independent of hyperglycemia or ketoacidosis and restored to normal by daily insulin treatment (NPH, 3-4 units/rat) for two to three weeks. Newly-synthesized brush border hydrolases were examined after 6 hours of intraperitoneal injection of ({sup 35}S) methionine (2 mCi) and found to be altered, suggesting that structural abnormality appeared acutely during intracellular synthesis rather than being due to slow extracellular modifications such as non-enzymatic glycosylation. Deglycosylation of brush border proteins by trifluoromethanesulfonic acid resulted in an apoprotein with normal electrophoretic migration in BB{sub d}, indicating that the alteration was due to the carbohydrates component of the glycoprotein. Pulse-chase studies with ({sup 35}S) methionine were consistent with normal protein an co-translational and initial N-linked carbohydrate assembly in association with the endoplasmic reticulum in BB{sub d}. However, the post-translational maturation of N-linked and addition of 0-linked carbohydrate chains in Golgi were prolonged, and produced a larger single-chain precursor of S-D in BB{sub d} than normal.

  2. Alterations of intestinal glycoprotein hydrolases in congenital diabetes

    International Nuclear Information System (INIS)

    Najjar, S.M.

    1989-01-01

    The diabetic BioBreed (BB d ) rat was used for the study of the molecular structure of intestinal brush border sucrase-α-dextrinase (SD) and aminooligopeptidase (AOP) in diabetes mellitus. The specific catalytic activity of S-D and AOP in the BB d rat is normal. However, solid-phase radioimmunoassay revealed loss of some antigenic determinants in the BB d rat. S-D and AOP migrated abnormally on 6% SDS-gel electrophoresis in the BB d rat. S was larger (+5 kDa), D was either smaller (-5 kDa) or unaltered, and AOP was smaller (-5 kDa) in the BB d than in the normal Wistar. The structural abnormalities were independent of hyperglycemia or ketoacidosis and restored to normal by daily insulin treatment (NPH, 3-4 units/rat) for two to three weeks. Newly-synthesized brush border hydrolases were examined after 6 hours of intraperitoneal injection of [ 35 S] methionine (2 mCi) and found to be altered, suggesting that structural abnormality appeared acutely during intracellular synthesis rather than being due to slow extracellular modifications such as non-enzymatic glycosylation. Deglycosylation of brush border proteins by trifluoromethanesulfonic acid resulted in an apoprotein with normal electrophoretic migration in BB d , indicating that the alteration was due to the carbohydrates component of the glycoprotein. Pulse-chase studies with [ 35 S] methionine were consistent with normal protein an co-translational and initial N-linked carbohydrate assembly in association with the endoplasmic reticulum in BB d . However, the post-translational maturation of N-linked and addition of 0-linked carbohydrate chains in Golgi were prolonged, and produced a larger single-chain precursor of S-D in BB d than normal

  3. Brush potential curve tracer

    Science.gov (United States)

    Finch, Hilvan A.

    1987-01-01

    A device for analyzing commutating characteristics of a motor or generator includes a holder for supporting a plurality of probes adjacent a brush of the motor or generator. Measurements of electrical current characteristics in each of the probes provides information useful in analyzing operation of the machine. Methods for employing a device in accordance with the invention are also disclosed.

  4. Immunochemical, biomolecular and biochemical characterization of bovine epithelial intestinal primocultures

    Directory of Open Access Journals (Sweden)

    Mainil Jacques

    2005-12-01

    Full Text Available Abstract Background Cultures of enterocytes and colonocytes represent valuable tools to study growth and differentiation of epithelial cells. In vitro models may be used to evaluate passage or toxicity of drugs, interactions of enteropathogenes bacteria strains with intestinal epithelium and other physiologic or pathologic phenomenon involving the digestive tract. Results Cultures of bovine colonocytes and jejunocytes were obtained from organoid-enriched preparations, using a combination of enzymatic and mechanical disruption of the intestine epithelium, followed by an isopicnic centrifugation discarding most single cells. Confluent cell monolayers arising from plated organoids exhibited epithelium typical features, such as the pavement-like structure, the presence of apical microvilli and tight junctions. Accordingly, cells expressed several markers of enterocyte brush border (i.e. maltase, alkaline phosphatase and fatty acid binding protein as well as an epithelial cytoskeleton component (cytokeratin 18. However, enterocyte primocultures were also positive for the vimentin immunostaining (mesenchyme marker. Vimentin expression studies showed that this gene is constitutively expressed in bovine enterocytes. Comparison of the vimentin expression profile with the pattern of brush border enzymes activities, suggested that the decrease of cell differentiation level observed during the enterocyte isolation procedure and early passages of the primoculture could result from a post-transcriptional de-repression of vimentin synthesis. The low differentiation level of bovine enterocytes in vitro could partly be counteracted adding butyrate (1–2 mM or using a glucose-deprived culture medium. Conclusion The present study describes several complementary approaches to characterize bovine primary cultures of intestinal cells. Cultured cells kept their morphologic and functional characteristics during several generations.

  5. [Improvement of intestinal absorption of poorly absorbable drugs by various sugar esters].

    Science.gov (United States)

    Yamamoto, Akira; Katsumi, Hidemasa; Kusamori, Kosuke; Sakane, Toshiyasu

    2014-01-01

    Effects of sucrose fatty acid esters (sugar esters) on the intestinal absorption of poorly absorbable drugs were examined by an in situ closed loop method in rats. 5(6)-Carboxyfluorescein (CF) and fluorescein isothiocyanate-dextrans (FDs) with various molecular weights were used as model drugs of poorly absorbable drugs. The absorption of CF from the rat small intestine was significantly enhanced in the presence of various sugar esters and a maximal absorption enhancing effect was observed in the presence of 0.5%(w/v) S-1670. The absorption enhancing effect of S-1670 in the small intestine decreased as the molecular weights of drugs increased. Moreover, we evaluated the intestinal membrane damage with or without various sugar esters. These sugar esters (0.5%(w/v)) did not increase the activities of lactate dehydrogenase (LDH), suggesting that these sugar esters did not cause serious membrane damage to the intestinal epithelium. Furthermore, these sugar esters increased membrane fluidity of lipid layers of the intestinal brush border membranes and decreased the transepithelial electrical resistance (TEER) of Caco-2 cells. Therefore, these findings suggested that these sugar esters might improve the intestinal absorption of poorly absorbable drugs via a transcellular and a paracellular pathways.

  6. Molecular aspects of intestinal calcium absorption.

    Science.gov (United States)

    Diaz de Barboza, Gabriela; Guizzardi, Solange; Tolosa de Talamoni, Nori

    2015-06-21

    Intestinal Ca(2+) absorption is a crucial physiological process for maintaining bone mineralization and Ca(2+) homeostasis. It occurs through the transcellular and paracellular pathways. The first route comprises 3 steps: the entrance of Ca(2+) across the brush border membranes (BBM) of enterocytes through epithelial Ca(2+) channels TRPV6, TRPV5, and Cav1.3; Ca(2+) movement from the BBM to the basolateral membranes by binding proteins with high Ca(2+) affinity (such as CB9k); and Ca(2+) extrusion into the blood. Plasma membrane Ca(2+) ATPase (PMCA1b) and sodium calcium exchanger (NCX1) are mainly involved in the exit of Ca(2+) from enterocytes. A novel molecule, the 4.1R protein, seems to be a partner of PMCA1b, since both molecules co-localize and interact. The paracellular pathway consists of Ca(2+) transport through transmembrane proteins of tight junction structures, such as claudins 2, 12, and 15. There is evidence of crosstalk between the transcellular and paracellular pathways in intestinal Ca(2+) transport. When intestinal oxidative stress is triggered, there is a decrease in the expression of several molecules of both pathways that inhibit intestinal Ca(2+) absorption. Normalization of redox status in the intestine with drugs such as quercetin, ursodeoxycholic acid, or melatonin return intestinal Ca(2+) transport to control values. Calcitriol [1,25(OH)₂D₃] is the major controlling hormone of intestinal Ca(2+) transport. It increases the gene and protein expression of most of the molecules involved in both pathways. PTH, thyroid hormones, estrogens, prolactin, growth hormone, and glucocorticoids apparently also regulate Ca(2+) transport by direct action, indirect mechanism mediated by the increase of renal 1,25(OH)₂D₃ production, or both. Different physiological conditions, such as growth, pregnancy, lactation, and aging, adjust intestinal Ca(2+) absorption according to Ca(2+) demands. Better knowledge of the molecular details of intestinal Ca(2

  7. Diagnostic and Research Aspects of Small Intestinal Disaccharidases in Coeliac Disease

    Directory of Open Access Journals (Sweden)

    Tanja Šuligoj

    2017-01-01

    Full Text Available Disaccharidases (DS are brush border enzymes embedded in the microvillous membrane of small intestinal enterocytes. In untreated coeliac disease (CD, a general decrease of DS activities is seen. This manuscript reviews different aspects of DS activities in CD: their utility in the diagnosis and their application to in vitro toxicity testing. The latter has never been established in CD research. However, with the recent advances in small intestinal organoid techniques, DS might be employed as a biomarker for in vitro studies. This includes establishment of self-renewing epithelial cells raised from tissue, which express differentiation markers, including the brush border enzymes. Determining duodenal DS activities may provide additional information during the diagnostic workup of CD: (i quantify the severity of the observed histological lesions, (ii provide predictive values for the grade of mucosal villous atrophy, and (iii aid diagnosing CD where minor histological changes are seen. DS can also provide additional information to assess the response to a gluten-free diet as marked increase of their activities occurs four weeks after commencing it. Various endogenous and exogenous factors affecting DS might also be relevant when considering investigating the role of DS in other conditions including noncoeliac gluten sensitivity and DS deficiencies.

  8. Water Soluble Responsive Polymer Brushes

    Directory of Open Access Journals (Sweden)

    Andrew J. Parnell

    2011-12-01

    Full Text Available Responsive polymer brushes possess many interesting properties that enable them to control a range of important interfacial behaviours, including adhesion, wettability, surface adsorption, friction, flow and motility. The ability to design a macromolecular response to a wide variety of external stimuli makes polymer brushes an exciting class of functional materials, and has been made possible by advances in modern controlled polymerization techniques. In this review we discuss the physics of polymer brush response along with a summary of the techniques used in their synthesis. We then review the various stimuli that can be used to switch brush conformation; temperature, solvent quality, pH and ionic strength as well as the relatively new area of electric field actuation We discuss examples of devices that utilise brush conformational change, before highlighting other potential applications of responsive brushes in real world devices.

  9. Border markets

    DEFF Research Database (Denmark)

    Walther, Olivier

    2014-01-01

    The objective of this issue of Articulo – Journal of Urban Research is to examine the characteristics of border markets in a comparative perspective. In this introductory paper, I first discuss what makes African border markets different from other markets, and examine several factors that explain...

  10. Intestinal glucose transport and salinity adaptation in a euryhaline teleost

    International Nuclear Information System (INIS)

    Reshkin, S.J.; Ahearn, G.A.

    1987-01-01

    Glucose transport by upper and lower intestinal brush-border membrane vesicles of the African tilapia (Oreochromis mossambicus) was characterized in fish acclimated to either freshwater of full-strength sea water. D-[ 3 H]-glucose uptake by vesicles was stimulated by a transmembrane Na gradient, was electrogenic, and was enhanced by countertransport of either D-glucose or D-galactose. Glucose transport was greater in the upper intestine than in the lower intestine and in sea water animals rather than in fish acclimated to freshwater. Glucose influx (10-s uptake) involved both saturable and nonsaturable transport components. Sea water adaptation increased apparent glucose influx K/sub t/, J/sub max/, apparent diffusional permeability (P), and the apparent Na affinity of the cotransport system in both intestinal segments, but the stoichiometry of Na-glucose transfer (1:1) was unaffected by differential saline conditions or gut region. It is suggested that increased sugar transport in sea water animals is due to the combination of enhanced Na-binding properties and an increase in number or transfer rate of the transport proteins. Freshwater animals compensate for reduced Na affinity of the coupled process by markedly increasing the protein affinity for glucose

  11. Bottle-Brush Brushes: Cylindrical Molecular Brushes of Poly(2-oxazoline) on Glassy Carbon

    KAUST Repository

    Zhang, Ning

    2009-07-28

    We report on the synthesis of brushes of bottle-brushes of poly(2-oxazoline)s on polished glassy carbon (GC) substrates. First, homogeneous and stable poly(2-isopropenyl-2-oxazoline) (PIPOx) brush layers with thicknesses up to 160 nm were created directly onto GC by the self-initiated photografting and photopolymerization (SIPGP) of 2-isopropenyl-2-oxazoline (IPOx). Kinetic studies reveal a linear increase in thickness with the polymerization time. In a second reaction, the pendant 2-oxazoline ring of the PIPOx brushes were used for the living cationic ring-opening polymerization (LCROP) with different substituted 2-oxazoline monomers to form the side chains. Also for the second surface-initiatedLCROPfrom the surface-bound macroinitiator brushes, the thickness increase with the polymerization time was found to be linear and reproducible. Characterization of the resulting bottle-brush brushes by FTIR spectroscopy,contact angle, and AFM indicates a high side chain grafting density and quantitative reactions. Finally, we have demonstrated the possibility of functionalizing the bottle-brush brushes side chain end groups with sterically demanding molecules. © 2009 American Chemical Society.

  12. Vascular Endothelial Growth Factor (VEGF) Bioavailability Regulates Angiogenesis and Intestinal Stem and Progenitor Cell Proliferation during Postnatal Small Intestinal Development.

    Science.gov (United States)

    Schlieve, Christopher R; Mojica, Salvador Garcia; Holoyda, Kathleen A; Hou, Xiaogang; Fowler, Kathryn L; Grikscheit, Tracy C

    2016-01-01

    Vascular endothelial growth factor (VEGF) is a highly conserved, master regulatory molecule required for endothelial cell proliferation, organization, migration and branching morphogenesis. Podocoryne carnea and drosophila, which lack endothelial cells and a vascular system, express VEGF homologs, indicating potential roles beyond angiogenesis and vasculogenesis. The role of VEGF in the development and homeostasis of the postnatal small intestine is unknown. We hypothesized regulating VEGF bioavailability in the postnatal small intestine would exhibit effects beyond the vasculature and influence epithelial cell stem/progenitor populations. VEGF mutant mice were created that overexpressed VEGF in the brush border of epithelium via the villin promotor following doxycycline treatment. To decrease VEGF bioavailability, sFlt-1 mutant mice were generated that overexpressed the soluble VEGF receptor sFlt-1 upon doxycycline administration in the intestinal epithelium. Mice were analyzed after 21 days of doxycycline administration. Increased VEGF expression was confirmed by RT-qPCR and ELISA in the intestine of the VEGF mutants compared to littermates. The VEGF mutant duodenum demonstrated increased angiogenesis and vascular leak as compared to littermate controls. The VEGF mutant duodenum revealed taller villi and increased Ki-67-positive cells in the transit-amplifying zone with reduced Lgr5 expression. The duodenum of sFlt-1 mutants revealed shorter villi and longer crypts with reduced proliferation in the transit-amplifying zone, reduced expression of Dll1, Bmp4 and VE-cadherin, and increased expression of Sox9 and EphB2. Manipulating VEGF bioavailability leads to profound effects on not only the intestinal vasculature, but epithelial stem and progenitor cells in the intestinal crypt. Elucidation of the crosstalk between VEGF signaling in the vasculature, mesenchyme and epithelial stem/progenitor cell populations may direct future cell therapies for intestinal

  13. Border installations

    International Nuclear Information System (INIS)

    Lenaerts, Koen

    1988-01-01

    Border installations cover all nuclear plants located near the border with a neighbouring state. However, the actual distance depends on the context. The distance can vary considerably. Also the prohibition on siting near a heavily populated area also defines the actual distance variably. The distance criteria may be modified by other factors of topography, prevailing climate and so on. Various examples which illustrate the problems are given. For example, the Creys-Melville nuclear power plant is 80km from Geneva and the Cattonam installation is 12km from the French border with Luxembourg and Germany. The Cattenom case is explained and the legal position within the European Institutions is discussed. The French licensing procedures for nuclear power stations are described with special reference to the Cattenom power plant. Border installations are discussed in the context of European Community Law and Public International Law. (U.K.)

  14. Effects of dietary glucose and sodium chloride on intestinal glucose absorption of common carp (Cyprinus carpio L.).

    Science.gov (United States)

    Qin, Chaobin; Yang, Liping; Zheng, Wenjia; Yan, Xiao; Lu, Ronghua; Xie, Dizhi; Nie, Guoxing

    2018-01-08

    The co-transport of sodium and glucose is the first step for intestinal glucose absorption. Dietary glucose and sodium chloride (NaCl) may facilitate this physiological process in common carp (Cyprinus carpio L.). To test this hypothesis, we first investigated the feeding rhythm of intestinal glucose absorption. Carps were fed to satiety once a day (09:00 a.m.) for 1 month. Intestinal samples were collected at 01:00, 05:00, 09:00, 13:00, 17:00 and 21:00. Result showed that food intake greatly enhanced sodium/glucose cotransporter 1 (SGLT1) and glucose transporter type 2 (GLUT2) expressions, and improved glucose absorption, with highest levels at 09:00 a.m.. Then we designed iso-nitrogenous and iso-energetic diets with graded levels of glucose (10%, 20%, 30%, 40% and 50%) and NaCl (0%, 1%, 3% and 5%), and submitted to feeding trial for 10 weeks. The expressions of SGLT1 and GLUT2, brush border membrane vesicles (BBMVs) glucose transport and intestinal villus height were determined after the feeding trial. Increasing levels of dietary glucose and NaCl up-regulated mRNA and protein levels of SGLT1 and GLUT2, enhanced BBMVs glucose transport in the proximal, mid and distal intestine. As for histological adaptive response, however, high-glucose diet prolonged while high-NaCl diet shrank intestinal villus height. Furthermore, we also found that higher mRNA levels of SGLT1 and GLUT2, higher glucose transport capacity of BBMVs, and higher intestinal villus were detected in the proximal and mid intestine, compared to the distal part. Taken together, our study indicated that intestinal glucose absorption in carp was primarily occurred in the proximal and mid intestine, and increasing levels of dietary glucose and NaCl enhanced intestinal glucose absorption in carp. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. New insights into the molecular mechanism of intestinal fatty acid absorption

    Science.gov (United States)

    Wang, Tony Y.; Liu, Min; Portincasa, Piero; Wang, David Q.-H.

    2013-01-01

    Background Dietary fat is the most important energy source of all the nutrients. Fatty acids, stored as triacylglycerols in the body, are an important reservoir of stored energy and derive primarily from animal fats and vegetable oils. Design Although the molecular mechanisms for the transport of water-insoluble amphipathic fatty acids across cell membranes have been debated for many years, it is now believed that the dominant means for intestinal fatty acid uptake is via membrane-associated fatty acid-binding proteins, i.e., fatty acid transporters on the apical membrane of enterocytes. Results These findings indicate that intestinal fatty acid absorption is a multistep process that is regulated by multiple genes at the enterocyte level, and intestinal fatty acid absorption efficiency could be determined by factors influencing intraluminal fatty acid molecules across the brush border membrane of enterocytes. To facilitate research on intestinal, hepatic and plasma triacylglycerol metabolism, it is imperative to establish standard protocols for precisely and accurately measuring the efficiency of intestinal fatty acid absorption in humans and animal models. In this review, we will discuss the chemical structure and nomenclature of fatty acids and summarize recent progress in investigating the molecular mechanisms underlying the intestinal absorption of fatty acids, with a particular emphasis on the physical-chemistry of intestinal lipids and the molecular physiology of intestinal fatty acid transporters. Conclusions A better understanding of the molecular mechanism of intestinal fatty acid absorption should lead to novel approaches to the treatment and the prevention of fatty acid-related metabolic diseases that are prevalent worldwide. PMID:24102389

  16. Ontogenetic development of nutrient transporters in rat intestine.

    Science.gov (United States)

    Toloza, E M; Diamond, J

    1992-11-01

    We measured intestinal brush-border uptakes of three sugars and three amino acids, plus intestinal morphometric parameters, in rats from the day of birth until adulthood. Rates of body weight gain had pronounced peaks in the suckling phase and again during weaning, separated by a dip at the onset of weaning. These two peaks coincided with peaks or plateaus in intestinal growth and in glucose (Glc) and proline (Pro) uptake capacities, which may provide the basis for high rates of body growth. Pro uptake declined relative to Glc uptake upon weaning, reflecting decreasing protein needs for growth and decreasing protein intake relative to carbohydrate intake. Fructose (Frc) and lysine uptake increased steeply on weaning, whereas galactose uptake declined relative to that of Glc. Rats prevented from normal weaning by being maintained on dry milk were generally similar to normal rats weaned onto chow. Notably, their Frc uptake still rose steeply on weaning despite low dietary Frc levels, suggesting hard-wired regulation of Frc transporter development. Our in vitro uptakes are similar to modern in vivo values in the same strain of rats. Nutrient uptake capacities exceed normal dietary intakes by only a modest safety margin.

  17. [Intestinal failure and transplantation in microvillous inclusion disease].

    Science.gov (United States)

    Fernández Caamaño, B; Quiles Blanco, M J; Fernández Tomé, L; Burgos Lizáldez, E; Sarría Osés, J; Molina Arias, M; Prieto Bozano, G

    2015-09-01

    Microvillous inclusion disease is a rare autosomal recessive condition, characterized by severe secretory diarrhea that produces a permanent intestinal failure and dependency on parenteral nutrition. It usually begins in the neonatal period, and the only treatment at present is intestinal transplantation. A retrospective review was conducted on 6 patients (three males and three females) diagnosed with microvillous inclusion disease between 1998 and 2013. All debuted in the first month of life, with a median age of three days (range, 3-30 days), and had secretory diarrhea dependent on parenteral nutrition, with fasting fecal volume of 150-200ml/kg/day. Light microscopy of duodenal biopsy samples showed varying degrees of villous atrophy without cryptic hyperplasia, accumulation of PAS positive material in the cytoplasm of enterocytes brush border, and anti-CD10 immunostaining was suggestive of intracytoplasmic inclusions. Diagnostic confirmation was performed with electron microscopy. Two of them had a genetic study, and showed mutations in MYO5B gene. Three died and three are alive; two of them with an intestinal transplantation and the third waiting for a multivisceral transplantation. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  18. Protein tyrosine phosphatase SAP-1 protects against colitis through regulation of CEACAM20 in the intestinal epithelium.

    Science.gov (United States)

    Murata, Yoji; Kotani, Takenori; Supriatna, Yana; Kitamura, Yasuaki; Imada, Shinya; Kawahara, Kohichi; Nishio, Miki; Daniwijaya, Edwin Widyanto; Sadakata, Hisanobu; Kusakari, Shinya; Mori, Munemasa; Kanazawa, Yoshitake; Saito, Yasuyuki; Okawa, Katsuya; Takeda-Morishita, Mariko; Okazawa, Hideki; Ohnishi, Hiroshi; Azuma, Takeshi; Suzuki, Akira; Matozaki, Takashi

    2015-08-04

    Intestinal epithelial cells contribute to regulation of intestinal immunity in mammals, but the detailed molecular mechanisms of such regulation have remained largely unknown. Stomach-cancer-associated protein tyrosine phosphatase 1 (SAP-1, also known as PTPRH) is a receptor-type protein tyrosine phosphatase that is localized specifically at microvilli of the brush border in gastrointestinal epithelial cells. Here we show that SAP-1 ablation in interleukin (IL)-10-deficient mice, a model of inflammatory bowel disease, resulted in a marked increase in the severity of colitis in association with up-regulation of mRNAs for various cytokines and chemokines in the colon. Tyrosine phosphorylation of carcinoembryonic antigen-related cell adhesion molecule (CEACAM) 20, an intestinal microvillus-specific transmembrane protein of the Ig superfamily, was greatly increased in the intestinal epithelium of the SAP-1-deficient animals, suggesting that this protein is a substrate for SAP-1. Tyrosine phosphorylation of CEACAM20 by the protein tyrosine kinase c-Src and the consequent association of CEACAM20 with spleen tyrosine kinase (Syk) promoted the production of IL-8 in cultured cells through the activation of nuclear factor-κB (NF-κB). In addition, SAP-1 and CEACAM20 were found to form a complex through interaction of their ectodomains. SAP-1 and CEACAM20 thus constitute a regulatory system through which the intestinal epithelium contributes to intestinal immunity.

  19. Brush seal performance measurement system

    OpenAIRE

    Aksoy, Serdar; Akşit, Mahmut Faruk; Aksit, Mahmut Faruk; Duran, Ertuğrul Tolga; Duran, Ertugrul Tolga

    2009-01-01

    Brush seals are rapidly replacing conventional labyrinth seals in turbomachinery applications. Upon pressure application, seal stiffness increases drastically due to frictional bristle interlocking. Operating stiffness is critical to determine seal wear life. Typically, seal stiffness is measured by pressing a curved shoe to brush bore. The static-unpressurized measurement is extrapolated to pressurized and high speed operating conditions. This work presents a seal stiffness measurement syste...

  20. Environmental and socio-demographic individual, family and neighborhood factors associated with children intestinal parasitoses at Iguazú, in the subtropical northern border of Argentina.

    Science.gov (United States)

    Rivero, Maria Romina; De Angelo, Carlos; Nuñez, Pablo; Salas, Martín; Motta, Carlos E; Chiaretta, Alicia; Salomón, Oscar D; Liang, Song

    2017-11-01

    Intestinal parasitoses are a major concern for public health, especially in children from middle and low-income populations of tropical and subtropical areas. We examined the presence and co-infection of parasites in humans as well as parasitic environmental contamination in Puerto Iguazú, Argentina. We explored the environmental and socio-demographic characteristics of the persistence of parasites in children and their environment. This cross-section survey was conducted among children population comprised into the area of the public health care centers of Iguazú during June 2013 to May 2016. Copro-parasitological status of 483 asymptomatic children was assessed. Simultaneously, a design-based sampling of 744 soil samples and 530 dog feces was used for characterize the environmental contamination. The 71.5% of these sites were contaminated. Sixteen genera were detected in the environment being hookworms (62.0%) the main pathogens group detected followed by Toxocara spp (16.3%), Trichuris spp (15.2%) and Giardia (6.5%). Total children prevalence raised 58.8%, detecting twelve genera of parasite with Giardia intestinalis as the most prevalent pathogen (29.0%) followed by Enterobius vermicularis (23.0%), Hymenolepis nana (12.4%) and hookworms (4.4%). Through questionnaires and census data, we characterized the socio-demographics conditions at an individual, family and neighborhood levels. A multi-level analysis including environmental contamination data showed that the ´presence of parasites´ was mostly determined by individual (e.g. age, playing habits, previous treatment) and household level (e.g. UBN, WASH, mother's literacy) determinants. Remarkably, to define the level of 'parasite co-infection', besides individual and household characteristics, environmental factors at a neighborhood level were important. Our work represents the major survey of intestinal parasites in human and environmental samples developed in the region. High prevalence was detected in

  1. Environmental and socio-demographic individual, family and neighborhood factors associated with children intestinal parasitoses at Iguazú, in the subtropical northern border of Argentina.

    Directory of Open Access Journals (Sweden)

    Maria Romina Rivero

    2017-11-01

    Full Text Available Intestinal parasitoses are a major concern for public health, especially in children from middle and low-income populations of tropical and subtropical areas. We examined the presence and co-infection of parasites in humans as well as parasitic environmental contamination in Puerto Iguazú, Argentina. We explored the environmental and socio-demographic characteristics of the persistence of parasites in children and their environment.This cross-section survey was conducted among children population comprised into the area of the public health care centers of Iguazú during June 2013 to May 2016. Copro-parasitological status of 483 asymptomatic children was assessed. Simultaneously, a design-based sampling of 744 soil samples and 530 dog feces was used for characterize the environmental contamination. The 71.5% of these sites were contaminated. Sixteen genera were detected in the environment being hookworms (62.0% the main pathogens group detected followed by Toxocara spp (16.3%, Trichuris spp (15.2% and Giardia (6.5%. Total children prevalence raised 58.8%, detecting twelve genera of parasite with Giardia intestinalis as the most prevalent pathogen (29.0% followed by Enterobius vermicularis (23.0%, Hymenolepis nana (12.4% and hookworms (4.4%. Through questionnaires and census data, we characterized the socio-demographics conditions at an individual, family and neighborhood levels. A multi-level analysis including environmental contamination data showed that the ´presence of parasites´ was mostly determined by individual (e.g. age, playing habits, previous treatment and household level (e.g. UBN, WASH, mother's literacy determinants. Remarkably, to define the level of 'parasite co-infection', besides individual and household characteristics, environmental factors at a neighborhood level were important.Our work represents the major survey of intestinal parasites in human and environmental samples developed in the region. High prevalence was

  2. Nature of elevated rat intestinal carbohydrase activities after high-carbohydrate diet feeding

    Energy Technology Data Exchange (ETDEWEB)

    Tsuboi, K.K.; Kwong, L.K.; Yamada, K.; Sunshine, P.; Koldovsky, O.

    1985-10-01

    Adult rats that were maintained on a low-carbohydrate intake showed rapid increase in the activities of sucrase, maltase, and lactase along the length of the small intestine when they were fed a high-starch diet. In the present study, the authors have identified these activity increases, and showed that they reflect proportional accumulations in enzyme-protein of sucrase-isomaltase, maltase-glucoamylase, and neutral lactase. It was determined that each of these enzymes exists in adult rat intestine in single immunoreactive form and accounts as a group for all sucrase, cellobiase, and most maltase and lactase activities. Dietary change from low to high carbohydrate (starch) resulted in an increase in (TH)leucine accumulation in each of the enzymes, without a change in the amount of label accumulation in total intestinal proteins. The increase in label accumulation in the brush-border carbohydrase pools was matched generally by proportional elevation in the pool concentrations of sucrase-isomaltase and lactase but not maltase. These studies suggest that the elevation of intestinal carbohydrase concentrations induced by high-carbohydrate feeding may involve selective stimulation of their synthesis.

  3. Nature of elevated rat intestinal carbohydrase activities after high-carbohydrate diet feeding

    International Nuclear Information System (INIS)

    Tsuboi, K.K.; Kwong, L.K.; Yamada, K.; Sunshine, P.; Koldovsky, O.

    1985-01-01

    Adult rats that were maintained on a low-carbohydrate intake showed rapid increase in the activities of sucrase, maltase, and lactase along the length of the small intestine when they were fed a high-starch diet. In the present study, the authors have identified these activity increases, and showed that they reflect proportional accumulations in enzyme-protein of sucrase-isomaltase, maltase-glucoamylase, and neutral lactase. It was determined that each of these enzymes exists in adult rat intestine in single immunoreactive form and accounts as a group for all sucrase, cellobiase, and most maltase and lactase activities. Dietary change from low to high carbohydrate (starch) resulted in an increase in [ 3 H]leucine accumulation in each of the enzymes, without a change in the amount of label accumulation in total intestinal proteins. The increase in label accumulation in the brush-border carbohydrase pools was matched generally by proportional elevation in the pool concentrations of sucrase-isomaltase and lactase but not maltase. These studies suggest that the elevation of intestinal carbohydrase concentrations induced by high-carbohydrate feeding may involve selective stimulation of their synthesis

  4. Intestinal mucosa in diabetes: synthesis of total proteins and sucrase-isomaltase

    International Nuclear Information System (INIS)

    Olsen, W.A.; Perchellet, E.; Malinowski, R.L.

    1986-01-01

    The effects of insulin deficiency on nitrogen metabolism in muscle and liver have been extensively studied with recent in vivo demonstration of impaired protein synthesis in rats with streptozotocin-induced diabetes. Despite the significant contribution of small intestinal mucosa to overall protein metabolism, the effect of insulin deficiency on intestinal protein synthesis have not been completely defined. The authors studied the effects of streptozotocin-induced diabetes on total protein synthesis by small intestinal mucosa and on synthesis of a single enzyme protein of the enterocyte brush-border membrane sucrase-isomaltase. They used the flood-dose technique to minimize the difficulties of measuring specific radioactivity of precursor phenylalanine and determined incorporation into mucosal proteins and sucrase-isomaltase 20 min after injection of the labeled amino acid. Diabetes did not alter mucosal mass as determined by weight and content of protein and DNA during the 5 days after injection of streptozotocin. Increased rates of sucrase-isomaltase synthesis developed beginning on day 3, and those of total protein developed on day 5. Thus intestinal mucosal protein synthesis is not an insulin-sensitive process

  5. Effect of Npt2b deletion on intestinal and renal inorganic phosphate (Pi) handling.

    Science.gov (United States)

    Ikuta, Kayo; Segawa, Hiroko; Sasaki, Shohei; Hanazaki, Ai; Fujii, Toru; Kushi, Aoi; Kawabata, Yuka; Kirino, Ruri; Sasaki, Sumire; Noguchi, Miwa; Kaneko, Ichiro; Tatsumi, Sawako; Ueda, Otoya; Wada, Naoko A; Tateishi, Hiromi; Kakefuda, Mami; Kawase, Yosuke; Ohtomo, Shuichi; Ichida, Yasuhiro; Maeda, Akira; Jishage, Kou-Ichi; Horiba, Naoshi; Miyamoto, Ken-Ichi

    2017-11-11

    Hyperphosphatemia is common in chronic kidney disease and is associated with morbidity and mortality. The intestinal Na + -dependent phosphate transporter Npt2b is thought to be an important molecular target for the prevention of hyperphosphatemia. The role of Npt2b in the net absorption of inorganic phosphate (Pi), however, is controversial. In the present study, we made tamoxifen-inducible Npt2b conditional knockout (CKO) mice to analyze systemic Pi metabolism, including intestinal Pi absorption. Although the Na + -dependent Pi transport in brush-border membrane vesicle uptake levels was significantly decreased in the distal intestine of Npt2b CKO mice compared with control mice, plasma Pi and fecal Pi excretion levels were not significantly different. Data obtained using the intestinal loop technique showed that Pi uptake in Npt2b CKO mice was not affected at a Pi concentration of 4 mM, which is considered the typical luminal Pi concentration after meals in mice. Claudin, which may be involved in paracellular pathways, as well as claudin-2, 12, and 15 protein levels were significantly decreased in the Npt2b CKO mice. Thus, Npt2b deficiency did not affect Pi absorption within the range of Pi concentrations that normally occurs after meals. These findings indicate that abnormal Pi metabolism may also be involved in tight junction molecules such as Cldns that are affected by Npt2b deficiency.

  6. Intestinal absorption and distribution of 14C-palmitic acid in an young Indian freshwater major carp, Labeo rohita (Hamilton)

    International Nuclear Information System (INIS)

    Sinha, G.M.; Chakrabarti, P.

    1983-01-01

    The mechanism of absorption and distribution of radioactive lipids in the various regions of the intestine and hepatopancreas of young Labeo rohita (Ham.) was investigated after feeding with small-sized earthworms (Pheretima posthuma), preinjected with 14 C-Palmitic acid. Dietary free fatty acids were mainly absorbed in the various regions (anterior, middle and posterior) of the intestine-the absorption capacity, however, varying greatly from region to region. The absorption of free fatty acids through the luminal brush border of the various regions of the intestine started at 24 hr of post-feeding (h.p.f.) with labelled diet and recorded its peak during 32 +- 2 h.p.f. However, middle intestine was found to be more active for such absorption than the other two regions (anterior and posterior). Incorporation of labelled Palmitic acid in the columnar epithelial cells and its subsequent transportation in the hepatic tissues, via lymphatic systems took place with in a short interval after absorption. However, absorption was completed within 40 h.p.f. when deposition of radioactive lipids was found to be maximum in the columnar epithelial cells of the various regions of the intestine and hepatic tissues. (author)

  7. Border poetics

    Directory of Open Access Journals (Sweden)

    Liv Lundberg

    2014-07-01

    Full Text Available The language of poetry is a language of inquiry, not the language of a genre. Poetry has the capacity of entering those zones known as borderlands, where you meet strange things and foreign people. In this poetic world view, the border is not an edge along the fringe of lands, societies and experiences, but rather their very middle – and their in-between. The structures of language are social structures in which meanings and intentions are already in place, always fighting for power and dominance, with rhetorical figures and more violent weapons.

  8. Subcloning, localization, and expression of the rat intestinal sodium-hydrogen exchanger isoform 8.

    Science.gov (United States)

    Xu, Hua; Chen, Rongji; Ghishan, Fayez K

    2005-07-01

    Apically expressed intestinal and renal sodium-hydrogen exchangers (NHEs) play a major role in Na(+) absorption. Our previous studies on NHE ontogeny have shown that NHE-2 and NHE-3 are expressed at very low levels in young animals. Furthermore, single and/or double NHE-2 and NHE-3 knockout mice display no obvious abnormalities before weaning. These observations suggest that other transporter(s) may be involved in intestinal Na+ absorption during early life. The present studies were designed to clone the novel rat intestinal NHE-8 cDNA and to decipher the NHE-8 protein localization and gene expression pattern during different developmental stages. The rat NHE-8 cDNA has 2,160 bp and encodes a 575-amino acid protein. An antibody against NHE-8 protein was developed. Immunohistochemistry staining indicated apical localization of NHE-8 protein in rat intestinal epithelial cells. The apical localization of NHE-8 was also confirmed by its presence in brush-border membrane and its absence in basolateral membrane preparations. Northern blotting utilizing a NHE-8-specific probe demonstrated higher NHE-8 mRNA expression in young animals compared with adult animals. Western blot analysis revealed a similar pattern. Tissue distribution with multiple human tissue RNA blot showed that NHE-8 was expressed in multiple tissues including the gastrointestinal tract. In conclusion, we have cloned the full-length NHE-8 cDNA from rat intestine and further showed its apical localization in intestinal epithelial cells. We have also shown that NHE-8 gene expression and protein expression were regulated during ontogeny. Our data suggests that NHE-8 may play an important role in intestinal Na+ absorption during early life.

  9. Circadian phenomena and irradiation. Modifications of enzyme activity in the small intestine after sublethal exposure

    Energy Technology Data Exchange (ETDEWEB)

    Becciolini, A.; Giache, V.; Scubla, E.; D' Abbondio, D.

    1987-01-01

    Irradiation effects after a 3 Gy dose administered at four different times of a 24 h light/darkness cycle were studied: The modifications in the brush border enzyme activity of epithelial cells of the small intestine were determined. In controls the activity of these enzymes showed circadian oscillations with the maximum during the dark period and the minimum during the light period. The trend after irradiation in the various groups was very similar but some differences were present specially at the initial intervals when the effect appeared to be different depending on the enzyme level at the time of exposure. Lactase activity in animals irradiated at 0.00 and 18.00 o'clock returned to control levels later than in the other groups.

  10. Localization and biosynthesis of aminopeptidase N in pig fetal small intestine

    DEFF Research Database (Denmark)

    Danielsen, E M; Niels-Christiansen, L L; Hansen, Gert Helge

    1995-01-01

    BACKGROUND & AIMS: Little is known about the expression of brush border enzymes in fetal enterocytes. The aim of this study was to describe the localization and biosynthesis of porcine fetal aminopeptidase N. METHODS: This study was performed using histochemistry and immunoelectron microscopy......, and large vacuoles in the apical cytoplasm. The transient high mannose-glycosylated form of fetal aminopeptidase N was processed to the mature complex-glycosylated form at a markedly slower rate than the enzyme in adult intestine. Likewise, dimerization occurred slowly compared with the adult form...... in the apical endocytic structures. CONCLUSIONS: In comparison with the adult enzyme, fetal aminopeptidase N has a more widespread subcellular distribution with substantial amounts present in apical endocytic compartments characteristic of the fetal enterocyte....

  11. Sweet brushes and dirty proteins

    NARCIS (Netherlands)

    Bosker, Wouter T. E.; Patzsch, Katja; Stuart, Martien A. Cohen; Norde, Willem

    2007-01-01

    We studied the protein repellency of dextran brushes. Dextran was grafted to a polystyrene surface in a broad range of grafting densities using polystyrene - dextran block copolymers and the Langmuir - Blodgett deposition technique. Ellipsometry measurements confirmed a successful transfer of the

  12. Putative interaction of brush cells with bicarbonate secreting cells in the proximal corpus mucosa

    Directory of Open Access Journals (Sweden)

    Julia Anna-Maria Eberle

    2013-07-01

    Full Text Available The gastric epithelium is protected from the highly acidic luminal content by alkaline mucus which is secreted from specialized epithelial cells. In the stomach of mice strong secretion of alkaline fluid was observed at the gastric groove, the border between corpus and fundus mucosa. Since this region is characterized by numerous brush cells it was proposed that these cells might secrete alkaline solution as suggested for brush cells in the bile duct. In fact, it was found that in this region multiple cells express elements which are relevant for the secretion of bicarbonate, including carbonic anhydrase (CAII, the cystic fibrosis transmembrane conductance regulator (CFTR and the Na+/H+ exchanger (NHE1. However, this cell population was distinct from brush cells which express the TRP-channel TRPM5 and are considered as putative sensory cells. The location of both cell populations in close proximity implies the possibility for a paracrine interaction. This view was substantiated by the finding that brush cells express prostaglandin synthase-1 (COX-1 and the neighbouring cells a specific receptor type for prostaglandins. The notion that brush cells may be able to sense a local acidification was supported by the observation that they express the channel PKD1L3 which contributes to the acid responsiveness of gustatory sensory cells. The results support the concept that brush cells may sense the luminal content and influence via prostaglandins the secretion of alkaline solution.

  13. 75 FR 13489 - Natural Bristle Paint Brushes and Brush Heads from the People's Republic of China: Final Results...

    Science.gov (United States)

    2010-03-22

    ... International Trade Administration (A-570-501) Natural Bristle Paint Brushes and Brush Heads from the People's... order on natural bristle paint brushes and brush heads from the People's Republic of China (``PRC...; Natural Bristle Paint Brushes and Brush Heads From the People's Republic of China, 51 FR 5580 (February 14...

  14. 75 FR 44939 - Natural Bristle Paint Brushes and Brush Heads from the People's Republic of China: Final Results...

    Science.gov (United States)

    2010-07-30

    ... Bristle Paint Brushes and Brush Heads from the People's Republic of China: Final Results of Changed... duty order on natural bristle paint brushes and brush heads from the People's Republic of China (``PRC... antidumping duty order on natural paint brushes and brush head in March 1986. See Antidumping Duty Order...

  15. Border installations

    International Nuclear Information System (INIS)

    Lenaerts, K.

    1988-01-01

    This chapter highlights the legal problems raised by the concept of a border installation. Using the Cattenom nuclear power plant as an example, the author describes the different stages of the legal conflict raised by construction of the plant and analyses the relationship between French administrative law and some provisions of the Euratom Treaty. Based on the Treaty, the Community institutions have adopted directives to strengthen inter-State co-operation and consultation between neighbouring countries. He observes that these principles of co-operation, consultation and vigilance already exist in public international law; however, international case law has not yet made it possible to establish the strict liability of the constructing state in case of a nuclear accident (NEA) [fr

  16. Postnatal development of monosaccharide transport in pig intestine.

    Science.gov (United States)

    Puchal, A A; Buddington, R K

    1992-05-01

    In vitro brush-border transport of three monosaccharides by pig intestine was studied as a function of postnatal age from immediately after birth before suckling to after weaning. Rates of transport normalized to tissue weight or surface area for glucose (Glc), galactose (Gal), and fructose (Fru) were highest at birth, with a steep decline after the onset of suckling, probably caused by any combination of three or more factors: reduced transporter site density, shifts in relative abundances of different monosaccharide transporters, and/or changes in activities of individual transporters. Whereas highest rates of Glc and Fru transport shifted from proximal to midintestine after weaning, Gal transport remained highest in proximal intestine. Postnatal increases in Km values for Gal, but not Glc, indicate there are multiple aldohexose transporters that undergo separate developmental trajectories. The presence of Fru transport in neonatal pigs may reflect a more advanced state of development than neonatal rats and rabbits, or may be an adaptation for early weaning. Changes in Fru-to-Glc and Gal-to-Glc transport ratios before weaning suggest transporter development is partly genetically hard-wired, apparently to prepare pigs for weaning. Curiously, Fru-to-Glc transport ratios were lower than those of rat and rabbit, but closely paralleled those of the carnivorous cat.

  17. Brush Seals for Improved Steam Turbine Performance

    Science.gov (United States)

    Turnquist, Norman; Chupp, Ray; Baily, Fred; Burnett, Mark; Rivas, Flor; Bowsher, Aaron; Crudgington, Peter

    2006-01-01

    GE Energy has retrofitted brush seals into more than 19 operating steam turbines. Brush seals offer superior leakage control compared to labyrinth seals, owing to their compliant nature and ability to maintain very tight clearances to the rotating shaft. Seal designs have been established for steam turbines ranging in size from 12 MW to over 1200 MW, including fossil, nuclear, combined-cycle and industrial applications. Steam turbines present unique design challenges that must be addressed to ensure that the potential performance benefits of brush seals are realized. Brush seals can have important effects on the overall turbine system that must be taken into account to assure reliable operation. Subscale rig tests are instrumental to understanding seal behavior under simulated steam-turbine operating conditions, prior to installing brush seals in the field. This presentation discusses the technical challenges of designing brush seals for steam turbines; subscale testing; performance benefits of brush seals; overall system effects; and field applications.

  18. 75 FR 37823 - Notice of Meeting of the Advisory Committee on Commercial Operations of Customs and Border...

    Science.gov (United States)

    2010-06-30

    ... DEPARTMENT OF HOMELAND SECURITY U.S. Customs and Border Protection [Docket No. USCBP-2010-0022... (COAC) AGENCY: U.S. Customs and Border Protection, Department of Homeland Security (DHS). ACTION: Notice... meeting will be held at the The Atheneum Suite Hotel, 1000 Brush Avenue, Grand Ballroom, 8th floor...

  19. Adaptation of intestinal enzymes to seasonal and dietary changes in a hibernator: the European hamster (Cricetus cricetus).

    Science.gov (United States)

    Galluser, M; Raul, F; Canguilhem, B

    1988-01-01

    Effects of diet, hibernation and seasonal variations on hydrolase activities were determined in mucosa and purified brush border membranes of the small intestine of European hamsters. Wild hamsters captured in April and fed for several weeks with an equilibrated laboratory chow (20% protein, 50% carbohydrates) exhibited a rise in disaccharidase activities (sucrase, isomaltase, lactase) but no changes in aminopeptidase N activity. During deep hibernation, in contrast to sucrase and isomaltase activities which showed only minor changes, lactase activity was significantly enhanced along the jejunoileum, and aminopeptidase N activity was maximum in the ileum. After a short period (48 h) of wakefulness and feeding following 10 days of starvation during the hibernation period, the activities of the disaccharidases and of aminopeptidase N returned to values measured in active animals. In contrast to the nutritional state, which has an important impact on the activities of intestinal enzymes, season has little effect on the intestine of the active animal under a controlled environment. The pattern of enzyme activities which occurs along the small intestine in the hibernating animal may be a prerequisite for optimum digestion during the short phases of waking during the hibernation period of the European hamster.

  20. Intestinal parasites in children, in highly deprived areas in the border region of Chiapas, Mexico Parasitosis intestinal en niños, en áreas de alta marginación socioeconómica de la región fronteriza de Chiapas, México

    Directory of Open Access Journals (Sweden)

    Emma Marianela Morales-Espinoza

    2003-10-01

    Full Text Available OBJECTIVE: To assess the prevalence of intestinal parasitic infections among children in highly deprived areas, and its possible association with demographic and socioeconomic indicators. MATERIAL AND METHODS: From March to September 1998 in a convenience sample of 32 communities of the border region of Chiapas, Mexico, selected at random based on the level of poverty and distance from the community to the nearest health care unit (OBJETIVO: Estimar la prevalencia de parasitosis intestinal en niños de zonas de alta marginación y su asociación con indicadores demográficos y socioeconómicos de interés. MATERIAL Y MÉTODOS: En una muestra de 1478 menores de edad, de entre 1 a 14 años, provenientes de 32 comunidades de la región fronteriza de Chiapas, México, de marzo a septiembre de 1998, se recolectaron tres muestras de heces fecales, seleccionadas aleatoriamente a partir del grado de marginación (alto y muy alto del municipio al que pertenecen, y distancia de la unidad de salud más cercana a la comunidad (<1 hora; 1 hora o más. En una de cada cuatro viviendas con niños menores de 15 años de edad, seleccionadas aleatoriamente, se obtuvieron tres muestras de heces fecales de éstos. Se efectuaron análisis bivariados con la prueba de ji cuadrada y multivariados con modelos lineales generalizados. RESULTADOS: La prevalencia global de parasitosis fue de 67% (intervalo de confianza IC 95% 64-70%. Sesenta por ciento de los niños estaban multiparasitados. La prevalencia de Entamoeba histolytica/E dispar fue de 51.2%, de Giardia lamblia, 18.3% y de Ascaris lumbricoides, 14.5%. La mayor prevalencia de E histolytica/E dispar se asoció con la edad y hablar algún idioma indígena; la de Ascaris lumbricoides con el sitio de obtención de agua y la carencia de refrigerador y electricidad. CONCLUSIONES: Es necesario hacer intervenciones locales de salud (calidad del agua, sistemas de desagüe, programas de educación sanitaria (promoción de la

  1. 1-alpha,25-Dihydroxyvitamin D3up-regulates the expression of 2 types of human intestinal alkaline phosphatase alternative splicing variants in Caco-2 cells and may be an important regulator of their expression in gut homeostasis.

    Science.gov (United States)

    Noda, Seiko; Yamada, Asako; Nakaoka, Kanae; Goseki-Sone, Masae

    2017-10-01

    Vitamin D insufficiency is associated with a greater risk of osteoporosis and also influences skeletal muscle functions, differentiation, and development. The principal function of vitamin D in calcium homeostasis is to increase the absorption of calcium from the intestine, and the level of alkaline phosphatase (ALP) activity, a differentiation marker for intestinal epithelial cells, is regulated by vitamin D. Intestinal-type ALP is expressed at a high concentration in the brush border membrane of intestinal epithelial cells, and is known to be affected by several kinds of nutrients. Recent reviews have highlighted the importance of intestinal-type ALP in gut homeostasis. Intestinal-type ALP controls bacterial endotoxin-induced inflammation by dephosphorylating lipopolysaccharide and is a gut mucosal defense factor. In this study, we investigated the influence of vitamin D on the expression of 2 types of alternative mRNA variants encoding the human alkaline phosphatase, intestinal (ALPI) gene in human Caco-2 cells as an in vitro model of the small intestinal epithelium. After treatment with 1-alpha,25-dihydroxyvitamin D 3 , the biologically active form of vitamin D 3 , there were significant increases in the ALP activities of Caco-2 cells. Inhibitor and thermal inactivation experiments showed that the increased ALP had properties of intestinal-type ALP. Reverse transcription-polymerase chain reaction analysis revealed that expression of the 2 types of alternative mRNA variants from the ALPI gene was markedly enhanced by vitamin D in Caco-2 cells. In conclusion, these findings agree with the hypothesis: vitamin D up-regulated the expression of 2 types of human intestinal alkaline phosphatase alternative splicing variants in Caco-2 cells; vitamin D may be an important regulator of ALPI gene expression in gut homeostasis. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Sodium/glucose cotransporter-1, sweet receptor, and disaccharidase expression in the intestine of the domestic dog and cat: two species of different dietary habit.

    Science.gov (United States)

    Batchelor, D J; Al-Rammahi, M; Moran, A W; Brand, J G; Li, X; Haskins, M; German, A J; Shirazi-Beechey, S P

    2011-01-01

    The domestic cat (Felis catus), a carnivore, naturally eats a very low carbohydrate diet. In contrast, the dog (Canis familiaris), a carno-omnivore, has a varied diet. This study was performed to determine the expression of the intestinal brush border membrane sodium/glucose cotransporter, SGLT1, sweet receptor, T1R2/T1R3, and disaccharidases in these species adapted to contrasting diets. The expression (this includes function) of SGLT1, sucrase, maltase and lactase were determined using purified brush border membrane vesicles and by quantitative immunohistochemistry of fixed tissues. The pattern of expression of subunits of the sweet receptor T1R2 and T1R3 was assessed using fluorescent immunohistochemistry. In proximal, middle, and distal small intestine, SGLT1 function in dogs was 1.9- to 2.3-fold higher than in cats (P = 0.037, P = 0.0011, P = 0.027, respectively), and SGLT1 protein abundance followed an identical pattern. Both cats and dogs express T1R3 in a subset of intestinal epithelial cells, and dogs, but not cats, express T1R2. In proximal and middle regions, there were 3.1- and 1.6-fold higher lactase (P = 0.006 and P = 0.019), 4.4- and 2.9-fold higher sucrase (both P cats. Dogs have a potential higher capacity to digest and absorb carbohydrates than cats. Cats may suffer from carbohydrate malabsorption following ingestion of high-carbohydrate meals. However, dogs have a digestive ability to cope with diets containing significant levels of carbohydrate.

  3. Tooth brushing for oral prophylaxis

    Directory of Open Access Journals (Sweden)

    Haruaki Hayasaki, DDS, PhD

    2014-08-01

    Full Text Available Control of plaque and debris is essential for the prevention of inflammatory periodontal diseases and dental caries, because plaque is the primary etiological factor in the introduction and development of both of these infection-oriented diseases. Plaque removal with a toothbrush is the most frequently used method of oral hygiene. Powered toothbrushes were developed beginning in the 1960s and are now widely used in developed countries. The bristles of a toothbrush should be able to reach and clean efficiently most areas of the mouth, and recently the design of both manual and powered toothbrushes has focused on the ability to reach and clean interproximal tooth surfaces. An individual's tooth brushing behavior, including force, duration, motivation and motion, are also critical to tooth brushing efficacy. Dental floss and the type of toothpaste play additional important roles as auxiliary tools for oral prophylaxis. Dental professionals should help their care-receivers’ meet the requirements of oral hygiene to maintain their QOL. This article reviews these topics.

  4. Dual wound dc brush motor gearhead

    Science.gov (United States)

    Henson, Barrie W.

    1986-01-01

    The design requirements, the design, development tests and problems, the qualification and life test and the findings of the strip examination of a dual wound DC brushed motor gearhead are described. It is the only space qualified dual wound dc brushed motor gearhead in Europe.

  5. BSA adsorption on bimodal PEO brushes

    NARCIS (Netherlands)

    Bosker, WTE; Iakovlev, PA; Norde, W; Stuart, Martien A. Cohen

    2005-01-01

    BSA adsorption onto bimodal PEO brushes at a solid surface was measured using optical reflectometry. Bimodal brushes consist of long (N = 770) and short (N = 48) PEO chains and were prepared on PS surfaces, applying mixtures of PS29-PEO48 and PS37-PEO770 block copolymers and using the

  6. BSA adsorption on bimodal PEO brushes

    NARCIS (Netherlands)

    Bosker, W.T.E.; Iakovlev, P.A.; Norde, W.; Cohen Stuart, M.A.

    2005-01-01

    BSA adsorption onto bimodal PEO brushes at a solid surface was measured using optical reflectometry. Bimodal brushes consist of long (N=770) and short (N=48) PEO chains and were prepared on PS surfaces, applying mixtures of PS 29-PEO48 and PS37-PEO770 block copolymers and using the Langmuir-Blodgett

  7. Tribological Tuft Testing Candidate Brush Seal Materials

    Science.gov (United States)

    DellaCorte, Chris

    1999-01-01

    This paper presents a tribological tuft test method of candidate brush seal materials in viewgraph form. The goals of the research are: 1) To develop test method to tribologically brush seal materials; 2) To evaluate materials to identify potential improvements and trends; and 3) Guide seal material development and selection.

  8. Ionic effects in collapse of polyelectrolyte brushes.

    Science.gov (United States)

    Jiang, Tao; Wu, Jianzhong

    2008-07-03

    We investigated the effect of counterion valence on the structure and swelling behavior of polyelectrolyte brushes using a nonlocal density functional theory that accounts for the excluded-volume effects of all ionic species and intrachain and electrostatic correlations. It was shown that charge correlation in the presence of multivalent counterions results in collapse of a polyelectrolyte brush at an intermediate polyion grafting density. At high grafting density, the brush reswells in a way similar to that in a monovalent ionic solution. In the presence of multivalent counterions, the nonmonotonic swelling of a polyelectrolyte brush in response to the increase of the grafting density can be attributed to a competition of the counterion-mediated electrostatic attraction between polyions with the excluded-volume effect of all ionic species. While a polyelectrolyte brush exhibits an "osmotic brush" regime at low salt concentration and a "salted brush" regime at high salt concentration regardless of the counterion valence, we found a smoother transition as the valence of the counterions increases. As observed in recent experiments, a quasi-power-law dependence of the brush thickness on the concentration ratio can be identified when the monovalent counterions are replaced with trivalent counterions at a fixed ionic strength.

  9. The Border Multiple

    DEFF Research Database (Denmark)

    Addressing and conceptualizing the changing character of borders in contemporary Europe, this book examines developments occurring in the light of European integration processes and an on-going tightening of Europe's external borders. Moreover, the book suggests new ways of investigating the nature...... of European borders by looking at border practices in the light of the mobility turn, and thus as dynamic, multiple, diverse and best expressed in everyday experiences of people living at and with borders, rather than focusing on static territorial divisions between states and regions at geopolitical level....... It provides border scholars and researchers as well as policymakers with new empirical and theoretical evidence on the de- and re-bordering processes going on in diverse border regions in Europe, both within and outside of the EU....

  10. Intestinal Cancer

    Science.gov (United States)

    ... connects your stomach to your large intestine. Intestinal cancer is rare, but eating a high-fat diet ... increase your risk. Possible signs of small intestine cancer include Abdominal pain Weight loss for no reason ...

  11. Characterization of Caco-2 cells stably expressing the protein-based zinc probe eCalwy-5 as a model system for investigating intestinal zinc transport.

    Science.gov (United States)

    Maares, Maria; Keil, Claudia; Thomsen, Susanne; Günzel, Dorothee; Wiesner, Burkhard; Haase, Hajo

    2018-01-29

    Intestinal zinc resorption, in particular its regulation and mechanisms, are not yet fully understood. Suitable intestinal cell models are needed to investigate zinc uptake kinetics and the role of labile zinc in enterocytes in vitro. Therefore, a Caco-2 cell clone was produced, stably expressing the genetically encoded zinc biosensor eCalwy-5. The aim of the present study was to reassure the presence of characteristic enterocyte-specific properties in the Caco-2-eCalwy clone. Comparison of Caco-2-WT and Caco-2-eCalwy cells revealed only slight differences regarding subcellular localization of the tight junction protein occludin and alkaline phosphatase activity, which did not affect basic integrity of the intestinal barrier or the characteristic brush border membrane morphology. Furthermore, introduction of the additional zinc-binding protein in Caco-2 cells did not alter mRNA expression of the major intestinal zinc transporters (zip4, zip5, znt-1 and znt-5), but increased metallothionein 1a-expression and cellular resistance to higher zinc concentrations. Moreover, this study examines the effect of sensor expression level on its saturation with zinc. Fluorescence cell imaging indicated considerable intercellular heterogeneity in biosensor-expression. However, FRET-measurements confirmed that these differences in expression levels have no effect on fractional zinc-saturation of the probe. Copyright © 2018 Elsevier GmbH. All rights reserved.

  12. Intestinal growth and pathology of Giardia duodenalis assemblage subtype A(I), A(II), B and E in the gerbil model.

    Science.gov (United States)

    Bénéré, E; Van Assche, T; Van Ginneken, C; Peulen, O; Cos, P; Maes, L

    2012-04-01

    This study investigated the significance of the genetic differences between assemblages A, B and E on intestinal growth and virulence. Intestinal growth and virulence were studied in 2 laboratory (A(I): WB and B: GS/M-83-H7) and 6 field isolates of assemblage subtype A(I), A(II), B and E(III). Intestinal trophozoite burdens, body weight and faecal consistency were monitored until day 29 post-infection (p.i.), morphological (mucosal architecture and inflammation) and functional (disaccharidase and alkaline phosphatase enzyme activity) damage to the small intestine were evaluated on days 7 and 18 p.i. The assemblage subtypes A(I) and B were more infectious and produced higher trophozoite loads for a longer period compared to the subtypes A(II) and E(III). The body weight of infected gerbils was significantly reduced compared to uninfected controls, but did not differ between the assemblage subtypes. Consistent softening of the faeces was only observed with assemblage B. Assemblage B next to assemblage subtype A(I) elicited relatively higher pathogenicity, characterized by more extensive damage to mucosal architecture, decreased brush-border enzyme function and infiltration of inflammatory cells. Assemblage E(III) and A(II) isolates showed relatively low virulence. The Giardia assemblage subtypes exhibit different levels of growth and virulence in the gerbil model.

  13. The Border Multiple

    DEFF Research Database (Denmark)

    of European borders by looking at border practices in the light of the mobility turn, and thus as dynamic, multiple, diverse and best expressed in everyday experiences of people living at and with borders, rather than focusing on static territorial divisions between states and regions at geopolitical level...

  14. Binary Polymer Brushes of Strongly Immiscible Polymers.

    Science.gov (United States)

    Chu, Elza; Babar, Tashnia; Bruist, Michael F; Sidorenko, Alexander

    2015-06-17

    The phenomenon of microphase separation is an example of self-assembly in soft matter and has been observed in block copolymers (BCPs) and similar materials (i.e., supramolecular assemblies (SMAs) and homo/block copolymer blends (HBCs)). In this study, we use microphase separation to construct responsive polymer brushes that collapse to generate periodic surfaces. This is achieved by a chemical reaction between the minor block (10%, poly(4-vinylpyridine)) of the block copolymer and a substrate. The major block of polystyrene (PS) forms mosaic-like arrays of grafted patches that are 10-20 nm in size. Depending on the nature of the assembly (SMA, HBC, or neat BCP) and annealing method (exposure to vapors of different solvents or heating above the glass transition temperature), a range of "mosaic" brushes with different parameters can be obtained. Successive grafting of a secondary polymer (polyacrylamide, PAAm) results in the fabrication of binary polymer brushes (BPBs). Upon being exposed to specific selective solvents, BPBs may adopt different conformations. The surface tension and adhesion of the binary brush are governed by the polymer occupying the top stratum. The "mosaic" brush approach allows for a combination of strongly immiscible polymers in one brush. This facilitates substantial contrast in the surface properties upon switching, previously only possible for substrates composed of predetermined nanostructures. We also demonstrate a possible application of such PS/PAAm brushes in a tunable bioadhesion-bioadhesive (PS on top) or nonbioadhesive (PAAm on top) surface as revealed by Escherichia coli bacterial seeding.

  15. [Tooth brushing in babies and toddlers].

    Science.gov (United States)

    de Groot-Nievaart, M A; Veerkamp, J S J

    2002-04-01

    The aim of this study was to investigate tooth brushing in toddlers and children younger than 4 years of age and the experiences of their parents. This study was performed in 3 towns in the middle of the Netherlands at the Office for Parent and Childcare. 99.4% of the children were brushed at least once a day during 0.5-1 minute. Tooth brushing is considered as a part of daily health care. Most children are cooperative and their parents enjoy brushing the teeth of their children. 17.5% of all parents experience problems with brushing teeth of their toddler or young child; 46% of them would like more information. But as the total number of children in a family increases, the parents' pleasure in brushing decreases. The Office for Parent and Childcare in the Netherlands has an important place in providing information on oral healthcare and especially tooth brushing for toddlers and children younger than 4 years of age. It would be useful to investigate how these healthcare workers get their dental information.

  16. Interfacial Friction and Adhesion of Polymer Brushes

    KAUST Repository

    Landherr, Lucas J. T.

    2011-08-02

    A bead-probe lateral force microscopy (LFM) technique is used to characterize the interfacial friction and adhesion properties of polymer brushes. Our measurements attempt to relate the physical structure and chemical characteristics of the brush to their properties as thin-film, tethered lubricants. Brushes are synthesized at several chain lengths and surface coverages from polymer chains of polydimethylsiloxane (PDMS), polystyrene (PS), and a poly(propylene glycol)-poly(ethylene glycol) block copolymer (PPG/PEG). At high surface coverage, PDMS brushes manifest friction coefficients (COFs) that are among the lowest recorded for a dry lubricant film (μ ≈ 0.0024) and close to 1 order of magnitude lower than the COF of a bare silicon surface. Brushes synthesized from higher molar mass chains exhibit higher friction forces than those created using lower molar mass polymers. Increased grafting density of chains in the brush significantly reduces the COF by creating a uniform surface of stretched chains with a decreased surface viscosity. Brushes with lower surface tension and interfacial shear stresses manifest the lowest COF. In particular, PDMS chains exhibit COFs lower than PS by a factor of 3.7 and lower than PPG/PEG by a factor of 4.7. A scaling analysis conducted on the surface coverage (δ) in relation to the fraction (ε) of the friction force developing from adhesion predicts a universal relation ε ∼ δ4/3, which is supported by our experimental data. © 2011 American Chemical Society.

  17. Intestinal fructose transport and malabsorption in humans.

    Science.gov (United States)

    Jones, Hilary F; Butler, Ross N; Brooks, Doug A

    2011-02-01

    Fructose is a hexose sugar that is being increasingly consumed in its monosaccharide form. Patients who exhibit fructose malabsorption can present with gastrointestinal symptoms that include chronic diarrhea and abdominal pain. However, with no clearly established gastrointestinal mechanism for fructose malabsorption, patient analysis by the proxy of a breath hydrogen test (BHT) is controversial. The major transporter for fructose in intestinal epithelial cells is thought to be the facilitative transporter GLUT5. Consistent with a facilitative transport system, we show here by analysis of past studies on healthy adults that there is a significant relationship between fructose malabsorption and fructose dose (r = 0.86, P fructose malabsorption with age have been observed in human infants, and this may parallel the developmental regulation of GLUT5 expression. Moreover, a GLUT5 knockout mouse has displayed the hallmarks associated with profound fructose malabsorption. Fructose malabsorption appears to be partially modulated by the amount of glucose ingested. Although solvent drag and passive diffusion have been proposed to explain the effect of glucose on fructose malabsorption, this could possibly be a result of the facilitative transporter GLUT2. GLUT5 and GLUT2 mRNA have been shown to be rapidly upregulated by the presence of fructose and GLUT2 mRNA is also upregulated by glucose, but in humans the distribution and role of GLUT2 in the brush border membrane are yet to be definitively decided. Understanding the relative roles of these transporters in humans will be crucial for establishing a mechanistic basis for fructose malabsorption in gastrointestinal patients.

  18. Comparing the efficiency of Denture brush and Ordinary brush in complete Denture cleaning

    Directory of Open Access Journals (Sweden)

    Amir Fayaz

    2013-11-01

    Full Text Available Please cite this article as: Fayaz A, Shakerian M, Ansari GH. Comparing the Efficiency of Denture brush and Ordinary brush in complete Denture cleaning. Novel Biomed 2013;1(2:62-65.Background & objective: Denture cleansing is a key element in retaining mucosa free of any inflammation. However, many denture users usually ignore this important factor. This investigation was designed to compare the efficacy of a denture brush and an ordinary brush in cleansing process of complete dentures.Materials & Methods: A group of 31 individuals aged 44-76 years were included in this study. Each patient was then instructed to use the denture brush for a period of 4 weeks while an ordinary brush was to be used for the following 4 weeks. Dentures were photographed and evaluated at every two week intervals using a computer photographic software assessment method. Pictures were compared using the image tool for plaque remaining on the denture surfaces. Student t-test was used to analyse data collected.Results: Comparison of the brush type efficacy at 2 and 4 weeks did not show any significant difference ( P>0.05 , however , clinical evaluation indicated that denture brush leaves much less plaque bio-film compare to the ordinary one, with mean plaque traced at 6.88 to 9.24 in 4 weeks.Conclusion: There were no significant differences found between the two brushes’ efficacy, with clinical evaluation significantly in favor of denture brush.

  19. Three-Wheel Brush-Wheel Sampler

    Science.gov (United States)

    Duckworth, Geoffrey A.; Liu, Jun; Brown, Mark G.

    2010-01-01

    A new sampler is similar to a common snow blower, but is robust and effective in sample collection. The brush wheels are arranged in a triangle shape, each driven by a brushless DC motor and planetary gearhead embedded in the wheel shaft. Its speed can be varied from 800 - 2,000 rpm, depending on the surface regolith resistance. The sample-collecting flow path, and internal features, are designed based on flow dynamics, and the sample-collecting rates have consistently exceeded the requirement under various conditions that span the range of expected surface properties. The brush-wheel sampler (BWS) is designed so that the flow channel is the main body of the apparatus, and links the brush-wheel assembly to the sample canister. The combination of the three brush wheels, the sample flow path, and the canister location make sample collection, storage, and transfer an easier task.

  20. Responsive polymer brushes for controlled nanoparticle exposure

    Science.gov (United States)

    Akkilic, Namik; Leermakers, Frans A. M.; de Vos, Wiebe M.

    2015-10-01

    We propose the design of a novel mixed polymer brush system that could act as a selective sensor with a distinct on-off switch. In the proposed system, a (single) nanoparticle (such as an antibody) is end-attached to a responsive chain, which is surrounded by a brush of nonresponsive chains. The collapse of the responsive chain leads to a protected state, where the nanoparticle is hidden in the polymer brush, while swelling of the responsive chain brings the nanoparticle outside of the brush into an exposed and active state. We investigate this system by numerical self-consistent field theory and predict a first-order like transition between the active state and the protective state at a critical decrease in solvent quality for the responsive chain. We show that by careful design of the brush parameters such as grafting density and chain length, for a given particle size, it is possible to fine-tune the desired switching mechanism.We propose the design of a novel mixed polymer brush system that could act as a selective sensor with a distinct on-off switch. In the proposed system, a (single) nanoparticle (such as an antibody) is end-attached to a responsive chain, which is surrounded by a brush of nonresponsive chains. The collapse of the responsive chain leads to a protected state, where the nanoparticle is hidden in the polymer brush, while swelling of the responsive chain brings the nanoparticle outside of the brush into an exposed and active state. We investigate this system by numerical self-consistent field theory and predict a first-order like transition between the active state and the protective state at a critical decrease in solvent quality for the responsive chain. We show that by careful design of the brush parameters such as grafting density and chain length, for a given particle size, it is possible to fine-tune the desired switching mechanism. Electronic supplementary information (ESI) available: Brush density profiles for different grafting

  1. Dependence of intestinal amino acid uptake on dietary protein or amino acid levels

    International Nuclear Information System (INIS)

    Karasov, W.H.; Solberg, D.H.; Diamond, J.M.

    1987-01-01

    To understand how intestinal amino acid (AA) transport is regulated by dietary substrate levels, the authors measured uptake of seven radioactively-labelled AAs and glucose across the jejunal brush-border membrane of mice kept on one of three isocaloric rations differing in nitrogen content. In the high-protein ration, uptake increased by 77-81% for the nonessential, less toxic AAs, proline, and aspartate but only by 32-61% for the more toxic essential AAs tested. In the nitrogen-deficient ration, uptake decreased for the nonessential aspartate and proline but stayed constant or increased for essential AAs and for the nonessential alanine. These patterns imply independent regulation of the intestine's various AA transporters. With decreasing dietary AA (or protein), the imino acid and acidic AA private transporters are repressed, while activities of the basic AA transporter and the neutral AA public transporter decrease to an asymptote or else go through a minimum. These regulatory patterns can be understood as a compromise among conflicting constraints imposed by protein's multiple roles as a source of calories, nitrogen, and essential AAs and by the toxicity of essential AAs at high concentrations

  2. 75 FR 34097 - Natural Bristle Paint Brushes and Brush Heads From the People's Republic of China: Notice of...

    Science.gov (United States)

    2010-06-16

    ... International Trade Administration Natural Bristle Paint Brushes and Brush Heads From the People's Republic of... circumstances review to revoke the antidumping duty order on natural bristle paint brushes and brush heads from the People's Republic of China (``PRC''). See generally, Antidumping Duty Order: Natural Bristle Paint...

  3. Luminal calcium concentration controls intestinal calcium absorption by modification of intestinal alkaline phosphatase activity.

    Science.gov (United States)

    Brun, Lucas R; Brance, María L; Rigalli, Alfredo

    2012-07-01

    Intestinal alkaline phosphatase (IAP) is a brush-border phosphomonoesterase. Its location suggests an involvement in the uptake of nutrients, but its role has not yet been defined. IAP expression parallels that of other proteins involved in Ca absorption under vitamin D stimulation. Experiments carried out in vitro with purified IAP have demonstrated an interaction between Ca and IAP. The gut is prepared to face different levels of Ca intake over time, but high Ca intake in a situation of a low-Ca diet over time would cause excessive entry of Ca into the enterocytes. The presence of a mechanism to block Ca entry and to avoid possible adverse effects is thus predictable. Thus, in the present study, Sprague-Dawley rats were fed with different amounts of Ca in the diet (0.2, 1 and 2 g%), and the percentage of Ca absorption (%Ca) in the presence and absence of L-phenylalanine (Phe) was calculated. The presence of Phe caused a significant increase in %Ca (52.3 (SEM 6.5) % in the presence of Phe v. 31.1 (sem 8.9) % in the absence of Phe, regardless of the amount of Ca intake; paired t test, P = 0.02). When data were analysed with respect to Ca intake, a significant difference was found only in the group with low Ca intake (paired t test, P = 0.03). Additionally, IAP activity increased significantly (ANOVA, P < 0.05) as Ca concentrations increased in the duodenal lumen. The present study provides in vivo evidence that luminal Ca concentration increases the activity of IAP and simultaneously decreases %Ca, acting as a minute-to-minute regulatory mechanism of Ca entry.

  4. Application of tooth brushing behavior to active rest.

    Science.gov (United States)

    Sadachi, Hidetoshi; Murakami, Yoshinori; Tonomura, Manabu; Yada, Yukihiro; Simoyama, Ichiro

    2010-01-01

    We evaluated the usefulness of tooth brushing with toothpaste as active rest using the flicker value as a physiological parameter and a subjective questionnaire as a psychological parameter. Seventeen healthy, right-handed subjects (12 males and 5 females) aged 22.5 +/- 1.5 yr (mean +/- standard deviation) were randomly divided into tooth brushing with toothpaste (N=9) and non-tooth brushing groups (N=8). The subjects performed a serial calculation task for 20 min using personal computers. Subsequently, the tooth brushing group brushed their teeth, and the flicker value and mood were compared before and after the tooth brushing. The flicker value significantly increased in the tooth brushing group compared with the non-tooth brushing group (pbrushing group, the incidence of a "feeling of being refreshed" significantly increased (pbrushing activated cerebral activity, producing refreshing effects. These results suggest the applicability of tooth brushing to active rest.

  5. Stratified polymer brushes from microcontact printing of polydopamine initiator on polymer brush surfaces.

    Science.gov (United States)

    Wei, Qiangbing; Yu, Bo; Wang, Xiaolong; Zhou, Feng

    2014-06-01

    Stratified polymer brushes are fabricated using microcontact printing (μCP) of initiator integrated polydopamine (PDOPBr) on polymer brush surfaces and the following surface initiated atom transfer radical polymerization (SI-ATRP). It is found that the surface energy, chemically active groups, and the antifouling ability of the polymer brushes affect transfer efficiency and adhesive stability of the polydopamine film. The stickiness of the PDOPBr pattern on polymer brush surfaces is stable enough to perform continuous μCP and SI-ATRP to prepare stratified polymer brushes with a 3D topography, which have broad applications in cell and protein patterning, biosensors, and hybrid surfaces. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Mechanisms of mercurial and arsenical inhibition of tyrosine absorption in intestine of the winter flounder Pseudopleuronectus americanus

    International Nuclear Information System (INIS)

    Musch, M.W.; Chauncey, B.; Schmid, E.C.; Kinne, R.K.; Goldstein, L.

    1990-01-01

    Effects of HgCl2 (100 microM) para-chloromercuribenzene sulfonate (PCMBS) (1 mM), and oxophenylarsine (OPA) (250 microM) were determined on (a) the rate of Na pump activity in intact winter flounder intestine; (b) activity of Na-K-ATPase in tissue homogenates; and (c) Na-dependent and Na-independent uptake of tyrosine in brush border membrane vesicles. Initial rate of uptake (influx) of 86Rb from the serosal solution of tissues mounted in Ussing chambers, a measure of Na-K-ATPase activity in the intact cell, was inhibited by all three agents with differing time courses. Rapidly permeating HgCl2 inhibited influx to the same degree as ouabain at 30 min, whereas the effects of PCMBS and OPA required 90 min. Cell potassium was also measured as an indirect indicator of ATPase activity and cell membrane permeability. All three agents decreased cell K, although effects on cell K lagged behind those for inhibition of the ATPase. At the concentrations used in the Ussing chamber (or at one-tenth concentration), all agents completely inhibited Na-K-ATPase activity in enzyme assays performed with tissue homogenates. In contrast, only HgCl2 decreased Na-dependent uptake of tyrosine by brush border membrane vesicles. These results suggest that mercurial and arsenical effects on tyrosine absorption are due to inhibition of the Na-K-ATPase thus decreasing the driving force for the cellular uptake by the Na-tyrosine cotransport system. Direct effects on Na-tyrosine cotransport may play a role in the inhibition observed with HgCl2, but not for PCMBS or OPA

  7. Modulation of intestinal glucose transport in response to reduced nitrogen supply in young goats.

    Science.gov (United States)

    Muscher-Banse, A S; Piechotta, M; Schröder, B; Breves, G

    2012-12-01

    The reduction of dietary protein is a common approach in ruminants to decrease the excretion of N because ruminants are able to recycle N efficiently by the rumino-hepatic circulation. In nonruminant species an impact on other metabolic pathways such as glucose metabolism was observed when dietary protein intake was reduced. However, an impact of dietary N reduction in goats on glucose metabolism especially on intestinal glucose absorption is questionable because ruminants have very efficient endogenous recycling mechanisms. Therefore, the aim of the present study was to characterize the intestinal absorption of glucose in growing goats kept on different N supply under isoenergetic conditions. The different CP concentrations (20, 16, 10, 9, and 7% CP) of the experimental diets were adjusted by adding urea to the rations. Intestinal flux rates of glucose were determined by Ussing chamber experiments. For a more mechanistic approach, the Na(+)-dependent uptake of glucose into intestinal brush-border membrane vesicles (BBMV) and the expression patterns of the Na(+)-dependent glucose transporter SGLT1 and the glucose transporter 2 (GLUT2) were determined. Reduced N intake resulted in a decrease of plasma glucose (P < 0.001) and insulin (P = 0.004) concentrations whereas the intestinal flux rates of glucose were elevated (P < 0.001), which were inhibited by phlorizin. However, the uptake of glucose into intestinal BBMV was not changed whereas the expression of SGLT1 on mRNA (P < 0.05) and protein abundance (P = 0.03) was decreased in response to a reduced N intake. The mRNA expression of GLUT2 was not affected. From these data, it can be concluded that the intestinal absorption of glucose was modulated by changes in dietary N intake. It is suggested that intracellular metabolism or basolateral transport systems or both might be activated during this feeding regimen because the apical located SGLT1 might not be involved. Therefore, an impact of dietary N reduction on

  8. Polymer brushes for antibiofouling and lubrication

    Directory of Open Access Journals (Sweden)

    Wufang Yang

    2017-09-01

    Full Text Available Surface-initiated atom transfer radical polymerization (SI-ATRP could provide many merits for the preparation of polymer brush, such as the well-defined chemical configurations, gradient, architecture and thickness. To date, SI-ATRP has been a popular strategy to tailor the physicochemical properties of material interfaces. In this short review, the recent progresses of our group and others’ in preparing methodologies of polymer brushes through SI-ATRP are highlighted in detail, including the fundamental mechanistic and superior characteristics. Some novel SI-ATRP techniques which are trigged by external-stimuli and the preparation of micro/nanoscale polymer hierarchical architecture with tailorable chemical components are also emphasized. Besides, since the polymer brush with different chemical components (e.g., single-component and multi-components and multi-scale structural characteristics shows great impact on the physicochemical properties at interface and polymer brush are generally sensitive to the external stimuli, the polymer chains modified surfaces acted as smart materials show great potential in many fields. The application advancements of polymer brush are reviewed mainly in two aspects, including antibiofouling and lubrication. Finally, the opportunities and challenges for further application are addressed.

  9. Intestinal Obstruction

    Science.gov (United States)

    ... the obstruction along the intestines. Treatment Suction via nasogastric tube Fluids given by vein Surgery for strangulation Sometimes ... nose and placed in the stomach (called a nasogastric tube) or into the intestine. Suction is applied to ...

  10. Business, brokers and borders

    DEFF Research Database (Denmark)

    Walther, Olivier

    Using social network analysis, this paper studies the structure of trade networks that developed across West African borders. The first part aims to understand the centralization of cross-border trade networks. In a business environment where transaction costs are extremely high, we find that dec......Using social network analysis, this paper studies the structure of trade networks that developed across West African borders. The first part aims to understand the centralization of cross-border trade networks. In a business environment where transaction costs are extremely high, we find...... developed with foreign partners from a different origin, religion or culture. In the second part, we study the spatial structure of trade networks and the influence of national borders on the development of social ties. The paper shows that the spatial form of trade networks is constrained by the historical...

  11. Human intestinal mucus proteins isolated by transanal irrigation and proctosigmoidoscopy

    OpenAIRE

    Paola Andrea Gómez Buitrago; Carlos Augusto González Correa; Mario Santacoloma Osorio; Gonzalo Taborda Ocampo; Marco Aurelio Zezzi Arruda

    2014-01-01

    Human intestinal mucus essentially consists of a network of Mucin2 glycoproteins embedded in many lower molecular weight proteins. This paper contributes to the proteomic study of human intestinal mucus by comparing two sample collection methods (transanal irrigation and brush cytology during proctosigmoidoscopy) and analysis techniques (electrophoresis and digestion in solution). The entire sample collection and treatment process is explained, including protein extraction, digestion and desa...

  12. Experimental evidence for in vitro fluid transport in the presence of a traditional medicinal fruit extract across rat everted intestinal sacs.

    Science.gov (United States)

    Mahomoodally, Mohamad Fawzi; Gurib-Fakim, Ameenah; Subratty, Anwar Hussein

    2005-02-01

    The present study was designed to investigate the effects of aqueous fruit extract of Momordica charantia (MC), a traditional medicinal plant, on the transport of fluid in vitro. Everted intestinal sacs from rats were mounted in an organ bath containing Krebs solution. We compared the effect of MC extract on water transport with increasing inorganic phosphate concentration with or without D-glucose in the buffer. In the control experiments, fluid uptake was enhanced significantly (P side inhibits the uptake of fluid significantly (P 0.05) when incubated with 3.0 mg/mL MC fruit extract. It is hypothesized that an increase in inorganic phosphate enhances oxidative phosphorylation thereby increasing the fluid uptake across everted intestinal sacs of rat. These findings seem to indicate that the MC-induced reduction on intestinal fluid absorption capacity could be mainly the result of an interference with the carrier-mediated coupled entrance of glucose and Na(+) across the brush-border membrane.

  13. Chemoprotective effect of taurine on potassium bromate-induced DNA damage, DNA-protein cross-linking and oxidative stress in rat intestine.

    Directory of Open Access Journals (Sweden)

    Mir Kaisar Ahmad

    Full Text Available Potassium bromate (KBrO3 is widely used as a food additive and is a major water disinfection by-product. It induces multiple organ toxicity in humans and experimental animals and is a probable human carcinogen. The present study reports the protective effect of dietary antioxidant taurine on KBrO3-induced damage to the rat intestine. Animals were randomly divided into four groups: control, KBrO3 alone, taurine alone and taurine+ KBrO3. Administration of KBrO3 alone led to decrease in the activities of intestinal brush border membrane enzymes while those of antioxidant defence and carbohydrate metabolism were also severely altered. There was increase in DNA damage and DNA-protein cross-linking. Treatment with taurine, prior to administration of KBrO3, resulted in significant attenuation in all these parameters but the administration of taurine alone had no effect. Histological studies supported these biochemical results showing extensive intestinal damage in KBrO3-treated animals and greatly reduced tissue injury in the taurine+ KBrO3 group. These results show that taurine ameliorates bromate induced tissue toxicity and oxidative damage by improving the antioxidant defence, tissue integrity and energy metabolism. Taurine can, therefore, be potentially used as a therapeutic/protective agent against toxicity of KBrO3 and related compounds.

  14. Chemoprotective effect of taurine on potassium bromate-induced DNA damage, DNA-protein cross-linking and oxidative stress in rat intestine.

    Science.gov (United States)

    Ahmad, Mir Kaisar; Khan, Aijaz Ahmed; Ali, Shaikh Nisar; Mahmood, Riaz

    2015-01-01

    Potassium bromate (KBrO3) is widely used as a food additive and is a major water disinfection by-product. It induces multiple organ toxicity in humans and experimental animals and is a probable human carcinogen. The present study reports the protective effect of dietary antioxidant taurine on KBrO3-induced damage to the rat intestine. Animals were randomly divided into four groups: control, KBrO3 alone, taurine alone and taurine+ KBrO3. Administration of KBrO3 alone led to decrease in the activities of intestinal brush border membrane enzymes while those of antioxidant defence and carbohydrate metabolism were also severely altered. There was increase in DNA damage and DNA-protein cross-linking. Treatment with taurine, prior to administration of KBrO3, resulted in significant attenuation in all these parameters but the administration of taurine alone had no effect. Histological studies supported these biochemical results showing extensive intestinal damage in KBrO3-treated animals and greatly reduced tissue injury in the taurine+ KBrO3 group. These results show that taurine ameliorates bromate induced tissue toxicity and oxidative damage by improving the antioxidant defence, tissue integrity and energy metabolism. Taurine can, therefore, be potentially used as a therapeutic/protective agent against toxicity of KBrO3 and related compounds.

  15. Chemoprotective Effect of Taurine on Potassium Bromate-Induced DNA Damage, DNA-Protein Cross-Linking and Oxidative Stress in Rat Intestine

    Science.gov (United States)

    Ahmad, Mir Kaisar; Khan, Aijaz Ahmed; Ali, Shaikh Nisar; Mahmood, Riaz

    2015-01-01

    Potassium bromate (KBrO3) is widely used as a food additive and is a major water disinfection by-product. It induces multiple organ toxicity in humans and experimental animals and is a probable human carcinogen. The present study reports the protective effect of dietary antioxidant taurine on KBrO3-induced damage to the rat intestine. Animals were randomly divided into four groups: control, KBrO3 alone, taurine alone and taurine+ KBrO3. Administration of KBrO3 alone led to decrease in the activities of intestinal brush border membrane enzymes while those of antioxidant defence and carbohydrate metabolism were also severely altered. There was increase in DNA damage and DNA-protein cross-linking. Treatment with taurine, prior to administration of KBrO3, resulted in significant attenuation in all these parameters but the administration of taurine alone had no effect. Histological studies supported these biochemical results showing extensive intestinal damage in KBrO3-treated animals and greatly reduced tissue injury in the taurine+ KBrO3 group. These results show that taurine ameliorates bromate induced tissue toxicity and oxidative damage by improving the antioxidant defence, tissue integrity and energy metabolism. Taurine can, therefore, be potentially used as a therapeutic/protective agent against toxicity of KBrO3 and related compounds. PMID:25748174

  16. Self-Assembling Brush Polymers Bearing Multisaccharides.

    Science.gov (United States)

    Lee, Jongchan; Kim, Jin Chul; Lee, Hoyeol; Song, Sungjin; Kim, Heesoo; Ree, Moonhor

    2017-06-01

    Three different series of brush polymers bearing glucosyl, maltosyl, or maltotriosyl moiety at the bristle end are successfully prepared by using cationic ring-opening polymerization and two sequential postmodification reactions. All brush polymers, except for the polymer containing 100 mol% maltotriosyl moiety, demonstrate the formation of multibilayer structure in films, always providing saccharide-enriched surface. These self-assembling features are remarkable, regarding the bulkiness of saccharide moieties and the kink in the bristle due to the triazole linker. The saccharide-enriched film surfaces reveal exceptionally high specific binding affinity to concanavalin A but suppress nonspecific binding of plasma proteins severely. Overall, the brush polymers bearing saccharide moieties of various kinds in this study are highly suitable materials for biomedical applications including biosensors. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. LM2500+ Brush Seal Case Study

    Science.gov (United States)

    Haaser, Fred G.

    2006-01-01

    The LM2500+ industrial aeroderivative gas turbine, a 25% enhanced power derivative of the LM2500 gas turbine, recently completed its development test program during the period 5/96 - 10/96. Early in the engine program a Quality Function Deployment (QFD) process was used to determine customer needs for this project.The feedback obtained from the QFD process showed without doubt that gas turbine customers now emphasize product reliability and availability at the top of their needs. One area of development on the LM2500+ was to investigate the use of a brush seal as a means to reduce undesirable turbine cooling leakages within the turbine mid frame in order to enhance part life. This presentation presents a case study on the factors that went into evaluating a brush seal during engine test, test results, and the ultimate decision not to implement the brush seal for cost and other reasons.

  18. Parents' reasons for brushing or not brushing their child's teeth: a qualitative study.

    Science.gov (United States)

    Trubey, Rob J; Moore, Simon C; Chestnutt, Ivor G

    2014-03-01

    Despite recent improvements in oral health, dental caries remains a significant source of morbidity for young children. Research has shown that regular toothbrushing with fluoride toothpaste reduces the risk of dental caries, but the factors that influence parental decisions about whether or not to brush their infant children's teeth at home are poorly understood. To develop an in-depth understanding of the issues that parents face from socio-economically deprived areas when trying to brush their young children's teeth at home. Fifteen parents of children aged 3-6 years took part in semi-structured telephone interviews, discussing factors relating to brushing their child's teeth at home. Thematic analysis was used to develop three themes. Parents discussed the difficulty of brushing their children's teeth in the evening, due to changing day-to-day routines, and the subsequent difficulty of forming a toothbrushing habit. Motivating factors for brushing children's teeth were largely short term. Satisfaction with brushing frequency was influenced more by perceptions of how often other parents brushed children's teeth than by the 'twice a day' norm or health outcomes. Results are discussed in relation to research and theories from the psychology and behavioural economics literature, and comparisons are drawn with assumptions inherent in more traditional oral health promotion messages. © 2013 John Wiley & Sons Ltd, BSPD and IAPD.

  19. Painting digitally : with Photoshop's brush tool

    OpenAIRE

    Mäkinen, Saara

    2011-01-01

    The reason I wanted to study Photoshop brushes is that with the right settings you can not only paint faster but also create more unique painting effects and styles. Photoshop is my main tool when painting digitally, but I noticed that I tend to use only the same type of default brush for everything I paint, be it smooth surfaces, organic shapes or modern structures. To be a concept artist you have to be able to paint fast. This means you need good tools to speed up the painting process. Look...

  20. Surface and Interface Analyses of Polymer Brushes by Synchrotron Radiation

    Science.gov (United States)

    Hoshino, Taiki; Tanaka, Yoshihito; Jinnai, Hiroshi; Takahara, Atsushi

    2013-02-01

    In the present review, we focus on the characterization of polymer brushes by quantum beam, which is regarded as a promising probe of surface and interface analysis. The polymer brushes were prepared on various shapes of surface, and proved to be benefit to various applications. Among them, the polymer brushes grafted on sphere nanoparticles and flat substrates are investigated as representative cases. The static structure of polymer brushes, especially the chain dimension of polymer brushes grafted on nanoparticles and a flat substrate, have been studied by small angle X-ray scattering (SAXS) and neutron reflectivity (NR), respectively. The microscopic dynamical properties of polymer brushes are also expected to be revealed by quantum beam. X-ray photon correlation spectroscopy (XPCS), a technique using a coherent X-ray, is one of the promising methods for microscopically understanding of dynamical properties of polymer brushes. Some of our recent studies about dynamical behavior of polymer brush immobilized nanoparticle by XPCS are also presented.

  1. Interaction between brushes of root-tethered dendrons

    NARCIS (Netherlands)

    Borisov, O.V.; Zhulina, E.B.; Polotsky, A.A.; Leermakers, F.A.M.; Birshtein, T.M.

    2014-01-01

    Polymer molecules densely tethered to surfaces (polymer brushes) can improve the colloidal stability of dispersion by protecting particles against aggregation. We use mean field and self-consistent field theoretical models to consider repulsive interactions between brushes of branched (dendritic)

  2. Social ranking effects on tooth-brushing behaviour

    OpenAIRE

    Maltby, John; Paterson, Kevin; Day, Liz; Jones, Ceri; Kinnear, Hayley; Buchanan, Heather

    2016-01-01

    Objective: A tooth-brushing social rank hypothesis is tested suggesting tooth-brushing duration is influenced when individuals position their behaviour in a rank when comparing their behaviour with other individuals.\\ud Design: Study 1 used a correlation design, Study 2 used a semi-experimental design, and Study 3 used a randomized intervention design to examine the tooth-brushing social rank hypothesis in terms of self-reported attitudes, cognitions, and behaviour towards tooth-brushing dura...

  3. Lactase-phlorizin hydrolase and aminopeptidase N are differentially regulated in the small intestine of the pig

    DEFF Research Database (Denmark)

    Torp, Niels; Rossi, M; Troelsen, J T

    1993-01-01

    The longitudinal expression of two brush-border enzymes, lactase-phlorizin hydrolase (EC 3.2.1.23/62) and aminopeptidase N (EC 3.4.11.2), was studied in the small intestine of the post-weaned pig. Whereas the level of mRNA, encoding aminopeptidase N (relative to that of beta-actin), only varied...... moderately from the duodenum to the terminal ileum, the amount of lactase-phlorizin hydrolase mRNA exhibited a sharp maximum in the proximal jejunum. For both enzymes, the level of protein synthesis, studied in cultured mucosal explants, correlated well with the level of mRNA, and no major variation in post...... in the gut lumen of pancreatic proteases. In neonatal animals, the level of mRNA for lactase-phlorizin hydrolase in both proximal and distal regions of the intestine was of the same magnitude as in the proximal jejunum of the post-weaned pigs. Our results point to two mechanisms that affect the expression...

  4. Mechanisms of calcium transport in small intestine. Overall review of the contract, September 1, 1972--March 1, 1975

    International Nuclear Information System (INIS)

    DeLuca, H.F.

    1975-01-01

    During the past three years considerable advance has been registered in our understanding of the mechanism of intestinal calcium transport, which is activated in response to 1,25-(OH) 2 D 3 , the active form of the vitamin in the system. In brush borders isolated from vitamin D-deficient chicks, a 200,000 molecular weight protein has been found by disc gel electrophoresis which is not present in chicks given vitamin D. This protein does not bind calcium and does not possess calcium dependent adenosine triphosphatase activity. Following the administration of 1,25-(OH) 2 D 3 to the deficient chicks this protein disappears from the disc gel profiles and a protein of molecular weight 220,000 appears in the gel profiles. This protein has been isolated and shown to possess calcium adenosine triphosphatase activity, alkaline phosphatase activity and it binds calcium. Work is progressing on the purification of these proteins with the ultimate aim of discerning what role they have in intestinal calcium transport. (U.S.)

  5. Identification and characterization of insulin receptors in basolateral membranes of dog intestinal mucosa

    International Nuclear Information System (INIS)

    Gingerich, R.L.; Gilbert, W.R.; Comens, P.G.; Gavin, J.R. III

    1987-01-01

    Little is known about hormonal regulation of substrate transport and metabolism in the mucosal lining of the small intestine. Because insulin regulates these functions in other tissues by binding to its receptor, we have investigated the presence of insulin receptors in canine small intestinal mucosa with basolateral membranes (BLM) and brush border membranes (BBM) prepared by sorbitol density centrifugation. A14-[ 125 I]iodoinsulin was used to study binding and structural characteristics of specific insulin receptors in BLM. Analysis of receptors in BLM identified binding sites with high affinity (Kd 88 pM) and low capacity (0.4 pmol/mg protein) as well as with low affinity (Kd 36 nM) and high capacity (4.7 pmol/mg protein). Binding was time, temperature, and pH dependent, and 125 I-labeled insulin dissociation was enhanced in the presence of unlabeled insulin. Cross-reactivity of these receptors to proinsulin, IGF-II, and IGF-I was 4, 1.8, and less than 1%, respectively. Covalent cross-linking of labeled insulin to BLM insulin receptors with disuccinimidyl suberate revealed a single 135,000-Mr band that was completely inhibited by unlabeled insulin. There was a 16-fold greater specific binding of insulin to BLM (39.0 +/- 2.4%) than to BBM (2.5 +/- 0.6%). These results demonstrate the presence of a highly specific receptor for insulin on the vascular, but not the luminal, surface of the small intestinal mucosa in dogs, and suggest that insulin may play an important role in the regulation of gastrointestinal physiology

  6. VSL#3 probiotic upregulates intestinal mucosal alkaline sphingomyelinase and reduces inflammation

    Science.gov (United States)

    Soo, Isaac; Madsen, Karen L; Tejpar, Qassim; Sydora, Beate C; Sherbaniuk, Richard; Cinque, Benedetta; Di Marzio, Luisa; Cifone, Maria Grazia; Desimone, Claudio; Fedorak, Richard N

    2008-01-01

    BACKGROUND: Alkaline sphingomyelinase, an enzyme found exclusively in bile and the intestinal brush border, hydrolyzes sphingomyelin into ceramide, sphingosine and sphingosine-1-phosphate, thereby inducing epithelial apoptosis. Reduced levels of alkaline sphingomyelinase have been found in premalignant and malignant intestinal epithelia and in ulcerative colitis tissue. Probiotic bacteria can be a source of sphingomyelinase. OBJECTIVE: To determine the effect of VSL#3 probiotic therapy on mucosal levels of alkaline sphingomyelinase, both in a mouse model of colitis and in patients with ulcerative colitis. METHODS: Interleukin-10 gene-deficient (IL10KO) and wild type control mice were treated with VSL#3 (109 colony-forming units per day) for three weeks, after which alkaline sphingomyelinase activity was measured in ileal and colonic tissue. As well, 15 patients with ulcerative colitis were treated with VSL#3 (900 billion bacteria two times per day for five weeks). Alkaline sphingomyelinase activity was measured through biopsies and comparison of ulcerative colitis disease activity index scores obtained before and after treatment. RESULTS: Lowered alkaline sphingomyelinase levels were seen in the colon (P=0.02) and ileum (P=0.04) of IL10KO mice, as compared with controls. Treatment of these mice with VSL#3 resulted in upregulation of mucosal alkaline sphingomyelinase activity in both the colon (P=0.04) and the ileum (P=0.01). VSL#3 treatment of human patients who had ulcerative colitis decreased mean (± SEM) ulcerative colitis disease activity index scores from 5.3±1.8946 to 0.70±0.34 (P=0.02) and increased mucosal alkaline sphingomyelinase activity. CONCLUSION: Mucosal alkaline sphingomyelinase activity is reduced in the intestine of IL10KO mice with colitis and in humans with ulcerative colitis. VSL#3 probiotic therapy upregulates mucosal alkaline sphingomyelinase activity. PMID:18354751

  7. Effect of White Kidney Beans (Phaseolus vulgaris L. var. Beldia) on Small Intestine Morphology and Function in Wistar Rats.

    Science.gov (United States)

    Nciri, Nader; Cho, Namjun; Bergaoui, Nacef; El Mhamdi, Faiçal; Ben Ammar, Aouatef; Trabelsi, Najoua; Zekri, Sami; Guémira, Fathi; Ben Mansour, Abderraouf; Sassi, Fayçal Haj; Ben Aissa-Fennira, Fatma

    2015-12-01

    The chronic ingestion of raw or undercooked kidney beans (Phaseolus vulgaris L.) causes functional and morphological derangement in various tissues. The major objectives of this study were to investigate the gavage effects of a raw Beldia bean variety that is widely consumed in Tunisia, on the small intestine morphology and jejunal absorption of water, electrolytes, and glucose in Wistar rats. Twenty young male rats were randomly divided into two groups of 10 rats. The first group served as the control and was gavaged with 300 mg of a rodent pellet flour suspension (RPFS), whereas the second experimental group was challenged with 300 mg of a Beldia bean flour suspension (BBFS) for 10 days. Histological studies were performed using light and electron microcopy. The intestinal transport of water, sodium, potassium, and glucose was studied by perfusing the jejunal loops of the small bowels in vivo. The feeding experiments indicated that BBFS did not affect weight gain. Histomorphometric analyses showed that the villus heights, crypt depths, and crypt/villus ratios in the jejunum and ileum were greater in the BBFS-fed rats than controls. Electron microscopy studies demonstrated that the rats exposed to RPFS exhibited intact intestinal tracts; however, the BBFS-treated rats demonstrated intestinal alterations characterized by abnormal microvillus architectures, with short and dense or long and slender features, in addition to the sparse presence of vesicles near the brush border membrane. BBFS administration did not significantly affect glucose absorption. However, significant decreases were observed in water and electrolyte absorption compared with the uptake of the controls. In conclusion, raw Beldia beans distorted jejunum morphology and disturbed hydroelectrolytic flux.

  8. Brushes and soap : grafted polymers and their interactions with nanocolloids

    NARCIS (Netherlands)

    Currie, E.P.K.

    2000-01-01

    Layers of polymer chains end-attached to a grafting plane at high densities, so-called brushes, are a curious state of matter. The (average) monomer density within the brush is as high as in a semi-dilute polymer solution, resulting in a high osmotic pressure in the brush. Due to the

  9. Increasing operational life of brush-contact device in the turbine generator due to using lubricating molybdenum disulphide brushes

    Science.gov (United States)

    Izotov, A. I.; Fominykh, A. A.; Nikulin, S. V.; Prokoshev, D. K.; Legoti, A. B.; Timina, N. V.

    2018-01-01

    A way of reducing irregular current distribution in multi-brush systems of sliding current transfer with its wear reduction due to installing lubricating molybdenum disulphide brushes on slip rings to ensure a greasing nano-sized cover on the slip ring surface is proposed. The authors give the results of industrial tests estimated on the performance effectiveness of lubricating brushes on slip rings of the TBB-320-2UZ-type turbine generator. The results showed that the lubricating brushes reduce a) the wear of 6110 OM+M and EG2AF+M brushes by 1.2 and 2.1 times respectively, b) current distribution irregularity in parallel operating brushes due to stabilizing the contact arc, and c) the temperature of the electrical brush-contact device due to the friction reduction in brushes.

  10. Border Crossing Entry Data

    Data.gov (United States)

    Department of Transportation — The Bureau of Transportation Statistics (BTS) Border Crossing/Entry Data provides summary statistics for inbound crossings at the U.S.-Canadian and the U.S.-Mexican...

  11. Responsive polymer brushes for biomedical applications

    NARCIS (Netherlands)

    Akkilic, Namik; de Vos, Wiebe Matthijs; Zhang, Johnathan

    2015-01-01

    The development of biomedical devices, biosensors, and medical implants is critically dependent on the engineering of “smart” surfaces that can adapt or respond to their local environment. The responsive polymer brush can be considered one of the most promising systems to create such smart surfaces.

  12. Cigarette smoking, tooth brushing characteristics, and perceived ...

    African Journals Online (AJOL)

    This study was conducted among four hundred non-dental undergraduates of University of Benin, Benin City, Nigeria to assess the prevalence of cigarette smoking, tooth brushing characteristics, perceived efficacy in oral self-care and preventing gingivodental diseases among them. The result showed that the perceived ...

  13. Anthrax Cases Associated with Animal-Hair Shaving Brushes.

    Science.gov (United States)

    Szablewski, Christine M; Hendricks, Kate; Bower, William A; Shadomy, Sean V; Hupert, Nathaniel

    2017-05-01

    During the First World War, anthrax cases in the United States and England increased greatly and seemed to be associated with use of new shaving brushes. Further investigation revealed that the source material and origin of shaving brushes had changed during the war. Cheap brushes of imported horsehair were being made to look like the preferred badger-hair brushes. Unfortunately, some of these brushes were not effectively disinfected and brought with them a nasty stowaway: Bacillus anthracis. A review of outbreak summaries, surveillance data, and case reports indicated that these cases originated from the use of ineffectively disinfected animal-hair shaving brushes. This historical information is relevant to current public health practice because renewed interest in vintage and animal-hair shaving brushes has been seen in popular culture. This information should help healthcare providers and public health officials answer questions on this topic.

  14. Structural and functional development of small intestine in intrauterine growth retarded porcine offspring born to gilts fed diets with differing protein ratios throughout pregnancy.

    Science.gov (United States)

    Mickiewicz, M; Zabielski, R; Grenier, B; Le Normand, L; Savary, G; Holst, J J; Oswald, I P; Metges, C C; Guilloteau, P

    2012-06-01

    Protein level in the maternal diet plays a crucial role in fetal programming during pregnancy. Low or high protein level increases the risk of intrauterine growth retardation (IUGR). The aim of this study was to investigate the structural and functional development of the small intestine in piglets from sows fed a control (C, 12.1% protein), a high protein (HP, 30% protein), or a low protein (LP, 6.5% protein) diet during pregnancy. Newborns were classified as IUGR (birth weight ≤1.18 kg) and non-IUGR (birth weight >1.18 kg). The piglets were euthanized on postnatal day (PD)1, PD28 and PD188. The LP diet in non-IUGR neonates resulted in decreased body weight on PD1. The LP and HP diets resulted in both decreased body weight and delayed catch-up growth in the IUGR piglets. The HP and LP-diets increased the length of villi on PD1 in non-IUGRs but not in IUGRs. At birth, the expressions of Ki67 and active caspase 3 in mid-jejunum epithelium of HP and LP non-IUGR neonates were significantly lower as compared to C non-IUGRs whilst in IUGRs the respective expressions were as high as in C non-IUGRs. The postnatal dynamics of brush border enzyme activities and vacuolated enterocytes disappearance showed significant drop in enterocyte maturation in IUGR as compared to non-IUGR neonates. In conclusion, both HP and LP diets led to retarded development of non-IUGR piglets. In IUGR piglets both HP and LP diets resulted in delayed catch-up growth, without adaptive changes in brush border digestive enzymes.

  15. Receptors for short-chain fatty acids in brush cells at the gastric groove

    Directory of Open Access Journals (Sweden)

    Julia Anna-Maria Eberle

    2014-04-01

    Full Text Available In the stomach of rodents clusters of brush cells are arranged at the gastric groove, immediately at the transition zone from the non-glandular reservoir compartment to the glandular digestive compartment. Based on their taste cell-like molecular phenotype it has been speculated that the cells may be capable to sense constituents of the ingested food, however, searches for nutrient receptors have not been successful. In this study, it was hypothesized that the cells may express receptors for short-chain fatty acids, metabolites generated by microorganisms during the storage of ingested food in the murine forestomach, which lacks the acidic milieu of more posterior regions of the stomach and is colonized with numerous microbiota. Experimental approaches, including RT-PCR analysis and immunohistochemical studies, revealed that the majority of these brush cells express the G-protein coupled receptor types GPR41 (FFAR3 and GPR43 (FFAR2, which are activated by short-chain fatty acids. Both, the GPR41 receptor proteins as well as an appropriate G-protein, α-gustducin, were found to be segregated at the apical brush border of the cells, indicating a direct contact with the luminal content of this gastric region. The exposure of microvillar processes with appropriate receptors and signaling elements to the gastric lumen suggests that the brush cells may in fact be capable to sense the short-chain fatty acids which originate from fermentation processes during the retention of ingested food in the anterior part of the stomach.

  16. Intestine transplantation

    Directory of Open Access Journals (Sweden)

    Tadeja Pintar

    2011-02-01

    Conclusion: Intestine transplantation is reserved for patients with irreversible intestinal failure due to short gut syndrome requiring total paranteral nutrition with no possibility of discontinuation and loss of venous access for patient maintenance. In these patients complications of underlying disease and long-term total parenteral nutrition are present.

  17. Vision, healing brush, and fiber bundles

    Science.gov (United States)

    Georgiev, Todor

    2005-03-01

    The Healing Brush is a tool introduced for the first time in Adobe Photoshop (2002) that removes defects in images by seamless cloning (gradient domain fusion). The Healing Brush algorithms are built on a new mathematical approach that uses Fibre Bundles and Connections to model the representation of images in the visual system. Our mathematical results are derived from first principles of human vision, related to adaptation transforms of von Kries type and Retinex theory. In this paper we present the new result of Healing in arbitrary color space. In addition to supporting image repair and seamless cloning, our approach also produces the exact solution to the problem of high dynamic range compression of17 and can be applied to other image processing algorithms.

  18. Fouling-resistant polymer brush coatings

    KAUST Repository

    Thérien-Aubin, Héloïse

    2011-11-01

    A major problem to be addressed with thin composite films used in processes such as coatings or water purification is the biofouling of the surface. To address this problem in a model system, functionalized polyaramide membranes containing an atom transfer radical polymerization (ATRP) initiator were synthesized as a versatile approach to easily modify the surface properties of the polyaramide. Poly(methacrylic acid) brushes were grown using surface initiated ATRP followed by the functionalization of the poly(methacrylic acid) brushes with different side-chains chosen to reduce adhesion between the membrane and foulant. The relation between membrane fouling and the physicochemical properties of the surface was investigated in detail. © 2011 Elsevier Ltd. All rights reserved.

  19. Hierarchical antifouling brushes for biosensing applications

    Czech Academy of Sciences Publication Activity Database

    de los Santos Pereira, Andres; Riedel, Tomáš; Brynda, Eduard; Rodriguez-Emmenegger, Cesar

    2014-01-01

    Roč. 202, 31 October (2014), s. 1313-1321 ISSN 0925-4005 R&D Projects: GA ČR GAP205/12/1702; GA MŠk(CZ) EE2.3.30.0029; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61389013 Keywords : hierarchically structured brushes * affinity biosensors * fouling Subject RIV: CE - Biochemistry Impact factor: 4.097, year: 2014

  20. Uses of the Westrup brush machine

    Science.gov (United States)

    Jill Barbour

    2002-01-01

    The Westrup brush machine can be used as the first step in the conditioning process of seeds. Even though there are various sizes of the machine, only the laboratory model (LA-H) is described. The machine is designed to separate seed from pods or flowers, dewing tree seed, remove appendages or hairs from seed, split twin seed, de-lint cotton seed, scarify hard coated...

  1. Antifouling polymer brushes displaying antithrombogenic surface properties

    Czech Academy of Sciences Publication Activity Database

    de los Santos Pereira, Andres; Sheikh, S.; Blaszykowski, C.; Pop-Georgievski, Ognen; Fedorov, K.; Thompson, M.; Rodriguez-Emmenegger, Cesar

    2016-01-01

    Roč. 17, č. 3 (2016), s. 1179-1185 ISSN 1525-7797 R&D Projects: GA ČR(CZ) GJ15-09368Y; GA MŠk(CZ) ED1.1.00/02.0109 Grant - others:OPPK(XE) CZ.2.16/3.1.00/21545 Program:OPPK Institutional support: RVO:61389013 Keywords : polymer brushes * surface characterization * antifouling surfaces Subject RIV: BO - Biophysics Impact factor: 5.246, year: 2016

  2. Phototriggered functionalization of hierarchically structured polymer brushes

    Czech Academy of Sciences Publication Activity Database

    de los Santos Pereira, Andres; Kostina, Nina Yu.; Bruns, M.; Rodriguez-Emmenegger, Cesar; Barner-Kowollik, C.

    2015-01-01

    Roč. 31, č. 21 (2015), s. 5899-5907 ISSN 0743-7463 R&D Projects: GA ČR(CZ) GJ15-09368Y; GA MŠk(CZ) ED1.1.00/02.0109 Grant - others:OPPK(XE) CZ.2.16/3.1.00/21545 Program:OPPK Institutional support: RVO:61389013 Keywords : polymer brushes * antifouling * click chemistry Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.993, year: 2015

  3. Border region studies

    DEFF Research Database (Denmark)

    Makkonen, Teemu; Williams, Allan

    2016-01-01

    The contemporary conditions of academic capitalism exert pressures on researchers to avoid ‘peripheral’ journals and ‘unfashionable’ topics. Here an attempt is made to shed light onto the structure of one such ‘offbeat’ field, namely ‘border region studies’, by discussing its geographical...... distribution, key themes, significance and impact. The review suggests that border region studies can be considered a significant and important ‘branch’ of regional studies, which accounts for a small but increasing proportion of regional studies research particularly in Europe and North America. Four main...

  4. Effect of brushing on fluoride release from 3 bracket adhesives.

    Science.gov (United States)

    Staley, Robert N; Mack, Steven J; Wefel, James S; Vargas, Marcos A; Jakobsen, Jane R

    2004-09-01

    The purpose of this in vitro study was to compare fluoride ion release from 3 orthodontic bracket adhesives with and without brushing the bracketed teeth with a fluoridated dentifrice. The bracket adhesives included a light-cured composite resin (Transbond; 3M Unitek, Monrovia, Calif), a fluoride-releasing composite resin (Advance; L D Caulk Division, Dentsply International, Milford, Del), and a resin-modified glass ionomer (Fuji Ortho LC; GC America, Alsip, Ill). The teeth in the control group were not bonded with brackets. Sixty extracted human teeth were randomly assigned to 6 groups of 10 each: (1) Transbond, brushed; (2) Advance, brushed; (3) Advance, not brushed; (4) Fuji, brushed; (5) Fuji, not brushed; and (6) control, brushed. After bonding, each tooth was placed in a sealed plastic test tube containing 4 ml of deionized water. The toothpaste used in brushing contained 0.15% weight per volume sodium fluoride, 1500 parts per million parts fluoride (Winter-fresh gel; Colgate-Palmolive Co., New York, NY). Brushing began 24 hours after the teeth were bonded and placed in deionized water. After brushing, the teeth were thoroughly rinsed with deionized water and returned to a sealed test tube. Fluoride measurements were taken before brushing began, at intervals of 72 hours for 22 days, and 90 and 93 days after bonding. Findings included: (1) brushing significantly increased the release of fluoride ions from the teeth in the composite resin and control groups, (2) the enamel crowns of the unbonded control teeth absorbed and re-released a substantial amount of fluoride ions obtained from the toothpaste, (3) the brushed group of teeth bonded with the fluoride-releasing composite resin released significantly more fluoride on the last 4 days that measurements were taken after brushing than the nonbrushed group bonded with the same adhesive, (4) the brushed group of teeth bonded with the resin-modified glass ionomer released significantly more fluoride on the last 4

  5. Presence of brush cells in the mouse gallbladder.

    Science.gov (United States)

    Luciano, L; Reale, E

    1997-09-15

    The brush cells (BC) are the second most frequent cellular component of the epithelium of the mouse gallbladder. They have a topographical distribution, being present in large numbers toward the neck and in the fundic regions of the organ and are scattered in the body. Serial section studies demonstrate that BC have a characteristic shape consisting of a narrow apical portion, bulky body and basal cytoplasmic projections. BC are located obliquely among the principal cells. Scanning electron microscopy demonstrates that the microvilli forming the prominent brush border, after which the cell was named, have a triangular arrangement. Due to their size and stiffness, the microvilli of BC have more similarity with stereocilia of sensory cells than with conventional microvilli. Furthermore freeze-fracture replicas demonstrate that, like stereocilia, the P face of the microvilli plasma membrane of BC is smoother than the E face but several intramembranous particles form small aggregates on the microvillus tip of both P and E faces. Numerous intramembranous particles are scattered on the lateral plasma membrane. An unusual, spatially organized cytoskeleton characterizes the apical cytoplasm of BC. The use of the appropriate fixative reveals that it consists of bundles of actin filaments originating from the axis of the apical microvilli and stretching continuously up to the supranuclear region of the cell. Microtubuli, also assembled in bundles, flank in alternating manner the actin filaments over their whole course. Due to the strong parallel arrangement of both cytoskeletal structures, the apical cytoplasm of the BC assumes a typical stiffness, observable in both thin sections and freeze-fracture replicas. A variable number of vesicles of different size are aligned between the bundles of actin filaments and microtubuli; their shape is highly influenced by the fixative used. Intraluminal injection of horseradish peroxidase demonstrates that these vesicles are not

  6. Polyelectrolyte brushes: a novel stable lubrication system in aqueous conditions.

    Science.gov (United States)

    Kobayashi, Motoyasu; Terada, Masami; Takahara, Atsushi

    2012-01-01

    Surface-initiated controlled radical copolymerizations of 2-dimethylaminoethyl methacrylate (DMAEMA), 2-(methacryloyloxy)ethyl phosphorylcholine (MPC), 2-(methacryloyloxy)ethyltrimethylammonium chloride) (MTAC), and 3-sulfopropyl methacrylate potassium salt (SPMK) were carried out on a silicon wafer and glass ball to prepare polyelectrolyte brushes with excellent water wettability. The frictional coefficient of the polymer brushes was recorded on a ball-on-plate type tribometer by linear reciprocating motion of the brush specimen at a selected velocity of 1.5 x 10(-3) m s-1 under a normal load of 0.49 N applied to the stationary glass ball (d = 10 mm) at 298 K. The poly(DMAEMA-co-MPC) brush partially cross-linked by bis(2-iodoethoxy)ethane maintained a relatively low friction coefficient around 0.13 under humid air (RH > 75%) even after 200 friction cycles. The poly(SPMK) brush revealed an extremely low friction coefficient around 0.01 even after 450 friction cycles. We supposed that the abrasion of the brush was prevented owing to the good affinity of the poly(SPMK) brush for water forming a water lubrication layer, and electrostatic repulsive interactions among the brushes bearing sulfonic acid groups. Furthermore, the poly(SPMK-co-MTAC) brush with a chemically cross-linked structure showed a stable low friction coefficient in water even after 1400 friction cycles under a normal load of 139 MPa, indicating that the cross-linking structure improved the wear resistance of the brush layer.

  7. Formation of gold nanoparticle assemblies in responsive polymer brushes

    Science.gov (United States)

    Christau, Stephanie; von Klitzing, Regine; Genzer, Jan

    2014-03-01

    The modification of surfaces by means of polymer brushes has become an active area of research during the past few years due to numerous potential applications of such systems in nano- and biotechnology. The structure and conformation of a brush depends on external stimuli such as pH, temperature or solvent type and can be manipulated by varying these attributes. This stimulus-response can be exploited for the development of smart surfaces and for sensor applications. Furthermore, brushes can be used as 3D matrices for immobilization of nanoparticles. In this study, responsive brushes are used as a matrix for the attachment of gold nanoparticles (AuNPs); this hybrid system exhibits intriguing optical properties due to the surface plasmon resonance of the AuNPs. We address the effect of some system parameters such as synthetic procedure, brush thickness, brush grafting density, particle size and particle incubation time on the characteristics of the resultant particle-impregnated brushes. We also discuss the spatial distribution of the AuNPs inside the brush with regard to the particle size, brush density and brush molecular weight.

  8. Dynamics of Brush-grafted Nanoparticles in Polymer Melts

    Science.gov (United States)

    Composto, Russell; Lin, Chia-Chun; Ohno, Kohji; Hore, Michael; Meth, Jeffrey; Clarke, Nigel; Winey, Karen

    2015-03-01

    Grafting a polymer brush to nanoparticles is an effective approach to achieve a good dispersion of nanoparticles in a polymer melt and the structure of this dispersion has been well studied. However, the interplay between the structure of the brush and nanoparticle diffusion is lacking. Here, we study the diffusion of poly (methyl methacrylate), or PMMA,-grafted iron oxide nanoparticles (core diameter=5nm) in PMMA melts. Different brush architectures are obtained by tuning brush molecular weight (16 and 21kg/mol), brush grafting density (0.17, 0.33 and 0.55 chains/nm2) and PMMA matrix molecular weight (4-70kg/mol). Preliminary results show that the diffusion of nanoparticles is slowed down relative to predictions of the classic Stokes-Einstein relation applied to a 5nm particle suggesting that the interpenetration between the brush and matrix influences nanoparticle mobility. Self-consistent field theory is performed to predict the structure of brush and matrix in the vicinity of the particle to quantify the effect of brush-matrix interpenetration. These experiments demonstrate that the structure of the brush could affect nanoparticle center of mass diffusion and the brush-nanoparticle interpenetration should be considered. Primary supports from NSF/EPSRC Materials World Network DMR 1210379 (KIW, RJC) and EP/5065373/1 (NC).

  9. From Borders to Margins

    DEFF Research Database (Denmark)

    Parker, Noel

    2009-01-01

    upon Deleuze's philosophy to set out an ontology in which the continual reformulation of entities in play in ‘post-international' society can be grasped.  This entails a strategic shift from speaking about the ‘borders' between sovereign states to referring instead to the ‘margins' between a plethora...

  10. Librarians Without Borders

    OpenAIRE

    Feridun Büyükyıldız

    2014-01-01

    It is not possible for librarians, who have an universal duty of sharing and presenting professional information, to stuck in their own borders. In this respect, this article gives brief information about the set-up of the Turkey base of “Librarians Without Borders” regarding that librarians also target all humanity just like doctors, lawyers, journalists, architects, teachers.

  11. Librarians Without Borders

    Directory of Open Access Journals (Sweden)

    Feridun Büyükyıldız

    2014-03-01

    Full Text Available It is not possible for librarians, who have an universal duty of sharing and presenting professional information, to stuck in their own borders. In this respect, this article gives brief information about the set-up of the Turkey base of “Librarians Without Borders” regarding that librarians also target all humanity just like doctors, lawyers, journalists, architects, teachers.

  12. Poly(lactic acid) Polymer Brushes as Dynamic Surfaces

    Science.gov (United States)

    Xu, Le Bo

    Degradable Poly(lactic acid), PLA, polymer brushes, were prepared to use as a temporary protective layer on a substrate. The PLA brushes degraded under basic conditions, which distinguished from bulk PLA, as well as PLA oligomer. The underlying substrate was able to be exposed with the removal of PLA brushes, resulting in a dynamic behavior. PLA brushes were grafted from silicon and gold substrates through surface initiated ring opening polymerization, ROP, of lactide catalyzed by tin octoate. The surface silanol groups on silicon and hydroxyl-terminated thiol self-assembled monolayers, SAMs, on gold were used as immobilized initiators for the surface initiated polymerization. The surface silanol groups worked equally well as the alcohol species to serve as initiator for the ROP of lactide. Synthesis conditions, such as temperature, monomer concentration and the type of catalyst and solvent, were explored to pursue the maximum brush thickness and well controlled growth on the surface. It was highlighted the different optimized synthesis conditions between the ROP in solution and the surface initiated ROP due to the equilibrium behavior of ROP. Both molecular weight and monomer conversion were considered in solution ROP. However, monomer conversion was not that important for surface ROP given merely trace amount of polymer was grafted on the surface as brushes. It was also demonstrated that the thickness of PLA brush could be tuned by varying either growth time or grafting density. The PLA brushes with a gradient thickness were prepared by gradually filling a reaction container with reactive solution. PLA brushes were able to be removed by immersing them in basic aqueous solution. The degradation of PLA brushes was found to be unique. Bulk PLA degraded under acidic conditions. The degradation of PLA oligomer occurred under both acidic and basic conditions. While the PLA brushes only degraded under basic conditions. The base-catalyzed degradation suggests the

  13. Professional brushing study comparing the effectiveness of sonic brush heads with manual toothbrushes: a single blinded, randomized clinical trial.

    Science.gov (United States)

    Pelka, Anna-Kristina; Nagler, Tonia; Hopp, Imke; Petschelt, Anselm; Pelka, Matthias Anton

    2011-08-01

    The aim of this study was to evaluate the plaque removal efficacy of four toothbrushes: the Philips Sonicare Elite with medium and mini brush heads, the Elmex Sensitive, and the American Dental Association (ADA) reference toothbrush. This study was a randomized, controlled, investigator-blinded, four-brush crossover design study, which examined plaque removal following a consecutive repeated use. All brushes were used on each participant in a randomly assigned quadrant of the mouth. A total of 90 subjects participated in the study. Prior to the experiment, they received a professional prophylaxis and were requested to refrain from toothbrushing for 48 h. Teeth were professionally brushed consecutively for 10 to 90 s per quadrant. A Turesky-modified Quigley Hein Index score was assessed at baseline and after each brushing interval by one blinded investigator. Results showed reduction of mean plaque scores for all brushes with time from 10 to 90 s. After 30 s (2-min whole mouth equivalent) of brushing, the Sonicare brushes cleaned 19, the ADA brush 16, and the Elmex Sensitive 10 of in average 28 tooth surfaces. With time, the number of additional cleaned surfaces decreased. Time is an important variable in the evaluation of plaque-removing efficacy since absolute efficacy increases with time and differs per toothbrush. No differences could be found between the two brush heads of the Sonicare.

  14. Illela border market: origin and contributions to trans-border ...

    African Journals Online (AJOL)

    Illela border market: origin and contributions to trans-border relations between Nigeria and Niger republic. ... cordial relations between her and her immediate neighbours and thus stem the scourge of smuggling and other trans-border crimes which have negatively affected the Nigerian economy and her international image.

  15. Partition of distinct chromosomal regions: negotiable border and fixed border.

    Science.gov (United States)

    Kimura, Akatsuki; Horikoshi, Masami

    2004-06-01

    Chromosomes are partitioned into distinct functional regions. For example, heterochromatin regions consist of condensed chromatin and contain few transcriptionally active genes, whereas euchromatin regions are less condensed and majority of active genes reside in the euchromatin regions. Because distinct regions reside in each chromosome, borders are accordingly established between these regions. A prevailing view of the borders is that they are 'walls' that actively inhibit communication between distinct regions on chromosomes. Although little is known about the molecular bases of these walls, specific DNA elements are considered to recruit these walls to define the positions of the borders. We call the borders established with this mechanism as 'fixed borders'. Past studies have identified various insulators (boundary DNA elements) that have been suggested to recruit fixed borders to them. Another mechanism, which we introduce and focus on in this review, does not require walls recruited by specific DNA elements at the chromosomal borders. Instead, the borders are defined by a balance of opposing enzymatic activities located at the opposite sides of the resultant borders. We name these borders 'negotiable borders'. Here we review some of the recent progress in the field that offer valuable insight into mechanisms of establishing structural and functional borders on chromosomes. Copyright Blackwell Publishing Limited

  16. "Border Sexualities, Border Families in Schools": Queering Education

    Science.gov (United States)

    Ryan, John

    2012-01-01

    This essay reviews Maria Pallotta-Chiarolli's (2010) Lambda Award-winning monograph "Border Sexualities, Border Families in Schools", in which queer and mestizage pedagogies frame a groundbreaking and highly accessible exploration of the issues that sexual border dwellers experience. Her particular focus areas are bisexual "sexually fluid"…

  17. Intestinal Ischemia

    Science.gov (United States)

    ... weight loss Intestinal ischemia Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  18. Domestic and international border effects

    OpenAIRE

    Hayakawa, Kazunobu

    2016-01-01

    Previous studies in the border-effect literature surprisingly found that domestic border effects are larger than international border effects (e.g., in the United States or Brazil). One interpretation of this result is that these estimates include the effects of producer agglomeration. Therefore, in this study, we estimate those border effects exclusively for transactions for final consumption, in which such agglomeration forces will be weak, in China and Japan. As a result, we found larger i...

  19. Bacterial adhesion and growth on a polymer brush-coating.

    Science.gov (United States)

    Nejadnik, M Reza; van der Mei, Henny C; Norde, Willem; Busscher, Henk J

    2008-10-01

    Biomaterials-related infections pose serious problems in implant surgery, despite the development of non-adhesive coatings. Non-adhesive coatings, like polymer brush-coatings, have so far only been investigated with respect to preventing initial bacterial adhesion, but never with respect to effects on kinetics of bacterial growth. Here, we compare adhesion and 20 h growth of three bacterial strains (Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa) on pristine and brush-coated silicone rubber in a parallel plate flow chamber. Brush-coatings were made using a tri-block copolymer of polyethylene oxide (PEO) and polypropylene oxide (PPO). Brush-coatings prevented adhesion of staphylococci to below 5 x 10(5)cm(-2) after 30 min, which is a 10-fold reduction compared to pristine silicone rubber. Biofilms grew on both brush-coated and pristine silicone rubber, while the viability of biofilms on brush-coatings was higher than on pristine silicone rubber. However, biofilms on brush-coatings developed more slowly and detached almost fully by high fluid shear. Brush-coating remained non-adhesive after S. epidermidis biofilm formation and subsequent removal whereas a part of its functionality was lost after removal of S. aureus biofilms. Adhesion, growth and detachment of P. aeruginosa were not significantly different on brush-coatings as compared with pristine silicone rubber, although here too the viability of biofilms on brush-coatings was higher. We conclude that polymer brush-coatings strongly reduce initial adhesion of staphylococci and delay their biofilm growth. In addition, biofilms on brush-coatings are more viable and easily removed by the application of fluid shear.

  20. [Clinical relevance of tooth brushing in relation to dental caries].

    Science.gov (United States)

    Pita-Fernández, Salvador; Pombo-Sánchez, Antonio; Suárez-Quintanilla, Juan; Novio-Mallón, Silvia; Rivas-Mundiña, Berta; Pértega-Díaz, Sonia

    2010-07-01

    To determine the impact and clinical relevance of tooth brushing on oral health. Prevalence study. Fontiñas Health Centre. (Santiago de Compostela, Spain). Prevalence study (n=281 children aged 5-14 years. Odontological examination according to WHO methodology, to determine the frequency of tooth brushing, frequency of sweet consumption and their impact on the prevalence of caries. Logistic regression and estimation of the relative prevalence difference (RPD) and the Number Needed to Treat in order to prevent one additional bad outcome (NNT). The children who never brush their teeth have a 40% (95% CI: 24.3%-57.8%) of early caries, while those who brush their teeth several times a day have 15.3% (95% CI: 9.4%-23.7%). An association between not brushing the teeth and caries in primary teeth (OR=2.3; 95% CI:1.05-5.3) was observed after adjusting for age, sweet consumption and visits to the dentist. The same occurred with final teeth (OR=3.9; 95% CI:1.4-10.3). The RPD was 62%(95% CI: 30%-79%), meaning that prevalence of caries is 62% lower in children who brush their teeth several times a day as compared to those who never brush their teeth. The NNT is 4 (95% CI: 2.4-14), so for every 4 children who brush their teeth several times a day, there is one less case of caries, compared to those who never brush their teeth. There is a dose-response relationship between prevalence of caries and brushing frequency. The same effect was observed with definitive caries: RPD=55% (95% CI:16%-76%), NNT=5 (95% CI:2.8-53.3). Tooth brushing is related to oral health, with a major clinical impact. The positive effect of tooth brushing was superior to that of a correct diet. 2009 Elsevier España, S.L. All rights reserved.

  1. [Freeze-etch study on the brush border structure of Cysticercus cellulosae].

    Science.gov (United States)

    Meng, X Q; Wang, S S; Zhou, W Q; Wang, B X; Zhang, Y Y; Liu, G S

    1991-01-01

    The images of C. cellulosae detected by freeze-itch technique were exactly similar to those observed in the thin section. The scolex microtriches might be divided into two parts, a thick proximal portion and a thinner spinal distal end, the former measuring about 0.2-0.4 micron in length, the latter measuring about 1-2 microns in length. On the extracellular surface of the proximal portion of microthrix, 1 or 2 particles could occasionally be seen, while numerous particles appeared on the protoplasmic fracture face (PF face) of the proximal portion. The PF face were closely packed and irregularly distributed with membranous particles, which were spherical or subspherical in shape, measured 0.01-0.02 micron in diameter. The extracellular fracture face (EF face), of proximal portion and all four membranous faces of spinal end were smooth. The tegumentary plasmic membrane was 0.02 micron in thickness, with smooth ES face. The PF face of this membrane packed closely with numerous particles, which were similar with those on the PF face of the microthrix. Numerous globular or discoidal vesicles scattered at random in the tegumentary matrix. Most mitochondria were near the basement membrane of the matrix. In the parenchymal layer, the parenchymal cells, calcareous corpuscles and flame-cells could easily be seen. Most of the calcareous corpuscles and flame-cells were located closely beneath the muscle layer. The flame-cell of C. cellulosae mainly consisted of three portions, cell body, a bundle of cilia and a filtered cell lumen. The flame-cell body had a large nucleus and relatively few cytoplasm with several mitochondria.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Bifidobacterium bifidum Monoassociation of Gnotobiotic Mice: Effect on Enterocyte Brush-Border Enzymes

    Czech Academy of Sciences Publication Activity Database

    Kozáková, Hana; Řeháková, Zuzana; Kolínská, Jiřina

    2001-01-01

    Roč. 46, č. 6 (2001), s. 573-576 ISSN 0015-5632 R&D Projects: GA ČR GA306/99/1383; GA ČR GA310/00/1371 Institutional research plan: CEZ:AV0Z5020903 Keywords : bifidum * gnotobiotic * effect Subject RIV: EE - Microbiology, Virology Impact factor: 0.776, year: 2001

  3. "Nonclassical" secretion of annexin A2 to the lumenal side of the enterocyte brush border membrane

    DEFF Research Database (Denmark)

    Danielsen, E Michael; van Deurs, Bo; Hansen, Gert H

    2003-01-01

    side of the microvilli, showing an apical secretion by a "nonclassical" mechanism. In addition, annexin A2 was associated with surface-connected, deep apical tubules in the apical terminal web region and with an underlying pleiomorphic, tubulo-vesicular compartment (subapical compartment...

  4. Lipid rafts in epithelial brush borders: atypical membrane microdomains with specialized functions

    DEFF Research Database (Denmark)

    Danielsen, E Michael; Hansen, Gert H

    2003-01-01

    of the apical surface sterically accessible for membrane fusion/budding events. Many of these invaginations appear as pleiomorphic, deep apical tubules that extend up to 0.5-1 microm into the underlying terminal web region. Their sensitivity to methyl-beta-cyclodextrin suggests them to contain cholesterol...

  5. Dicyclohexylcarbodiimide (DCCD) sensitive organic cation/H/sup +/ antiporter in renal brush border membrane vesicles (BBMV)

    Energy Technology Data Exchange (ETDEWEB)

    Sokol, P.P.; Holohan, P.D.; Ross, C.R.

    1986-03-01

    We tested the hypothesis that organic cation transport in BBMV is coupled to the countertransport of a H/sup +/ by employing a prototypic organic cation, N/sup 1/-methylnicotinamide (NMN), and a rapid filtration assay. Two H/sup +/ gradient uncouplers, carbonyl cyanide m-chlorophenylhydrazone (CCCP)/sub 3/ and gramicidin D were effective in dissipating H/sup +/ driven (/sup 3/H)NMN transport. Nigericin, a K/sup +//H/sup +/ exchanger, generated a H/sup +/ gradient in situ which drove the net accumulation of NMN. The molecular mechanism of H/sup +/ coupling was examined employing DCCD, a hydrophobic carbodiimide, which inactivates essential carboxylate groups, the putative H/sup +/ receptor. DCCD inactivated NMN transport irreversibly with an IC/sub 50/ of 2.6..mu..M whereas the hydrophilic carbodiimide, 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide, did not. DCCD inactivation followed pseudo-first-order kinetics and was not affected by NMN. A double logarithmic plot of the apparent rate constants vs. (DCCD) gave a slope of 0.8. The data are consistent with a simple bimolecular reaction mechanism and imply that one molecule of DCCD inactivates one carboxylate group per active transport unit. The results show that (1) the transport of organic cations is coupled to the countermovement of a H/sup +/ and (2) a carboxylate group is essential for H/sup +/ binding and translocation.

  6. Effect of E.coli association on brush border enzyme function in gnotobiotic pigs

    Czech Academy of Sciences Publication Activity Database

    Kozáková, Hana; Šinkora, Jiří; Cukrowska, Božena; Řeháková, Zuzana; Kolínská, Jiřina; Lojda, Z.; Tlaskalová, Helena

    2001-01-01

    Roč. 54, Suppl 1 (2001), s. 1033 ISSN 0300-9475. [International Congress of Immunology /11./. 22.07.2001-27.07.2001, Stockholm] Institutional research plan: CEZ:AV0Z5020903 Subject RIV: EC - Immunology

  7. Apolipoprotein A-1 (apoA-1) deposition in, and release from, the enterocyte brush border

    DEFF Research Database (Denmark)

    Danielsen, E Michael; Hansen, Gert H; Rasmussen, Karina

    2012-01-01

    resistant membranes (DRMs), indicative of localization in lipid raft microdomains. The apolipoprotein was not readily released from microvillar vesicles by high salt or by incubation with phosphatidylcholine-specific phospholipase C or trypsin, indicating a relatively firm attachment to the membrane bilayer...

  8. Plasma lipopolysaccharide level and enterocyte brush border enzymes in gnotobiotic piglets infected with Salmonella typhimurium

    Czech Academy of Sciences Publication Activity Database

    Trebichavský, Ilja; Kozáková, Hana; Šplíchal, Igor

    2002-01-01

    Roč. 47, - (2002), s. 289-294 ISSN 8750-7943 R&D Projects: GA ČR GA524/01/0917; GA AV ČR IAA5020101 Institutional research plan: CEZ:AV0Z5020903 Keywords : swine * gnotobiotic piglet * salmonella typhimurium Subject RIV: EE - Microbiology, Virology Impact factor: 0.107, year: 2002

  9. Intestinal Coccidia

    OpenAIRE

    MJ Ggaravi

    2007-01-01

    Intestinal Coccidia are a subclass of Apicomplexa phylum. Eucoccidida are facultative heteroxenous, but some of them are monoxenous. They have sexual and asexual life cycle. Some coccidia are human pathogens, for example: Cryptosporidium: Cryptosporidiums has many species that are mammalian intestinal parasites.C. Parvum specie is a human pathogenic protozoa. Cryptosporidum has circle or ellipse shapes and nearly 4-6 mm. It is transmitted in warm seasons. Oocyst is obtained insexual life cycl...

  10. Regulatory signals for intestinal amino acid transporters and peptidases

    International Nuclear Information System (INIS)

    Ferraris, R.P.; Kwan, W.W.; Diamond, J.

    1988-01-01

    Dietary protein ultimately regulates many processes involved in protein digestion, but it is often unclear whether proteins themselves, peptides, or amino acids (AAs) are the proximate regulatory signal. Hence the authors compared several processes involved in protein digestion in mice adapted to one of three rations, identical except for containing 54% of either casein, a partial hydrolysate of casein, or a free AA mixture simulating a complete hydrolysate of casein. The authors measured brush-border uptakes of seven AAs that variously serve as substrates for four AA transporters, and brush-border and cytosolic activities of four peptidases. The three rations yielded essentially the same AA uptake rates. Peptidase activities tended to be lower on the AA ration than on the protein ration. In other studies, all three rations yielded the same rates of brush-border peptide uptake; protein is only modestly more effective than AAs at inducing synthesis of pancreatic proteases; and, depending on the animal species, protein is either much less or much more effective than AAs at stimulating release of cholecystokinin and hence of pancreatic enzymes. Thus the regulators of each process involved in protein digestion are not necessarily that process's substrate

  11. Magnetohydrodynamic instability of a cylindrical liquid-metal brush

    International Nuclear Information System (INIS)

    Hong, S.H.; Wilhelm, H.E.

    1976-01-01

    The stability of a homopolar generator brush, consisting of a liquid-metal-filled cavity between rotating (rotor) and fixed (stator) cylinder electrodes, is analyzed in the presence of radial current transport and an axial homogeneous magnetic field. Within the frame of linear magnetohydrodynamics, it is shown that the liquid-metal flow in the brush is always unstable if the brush transports current. In the absence of current flow (infinite load) the axial magnetic field stabilizes the liquid-metal flow in the brush if the magnetic energy density is larger than a certain fraction of the energy density of the rotating fluid

  12. Antifouling Properties of Fluoropolymer Brushes toward Organic Polymers: The Influence of Composition, Thickness, Brush Architecture, and Annealing.

    Science.gov (United States)

    Wang, Zhanhua; Zuilhof, Han

    2016-07-05

    Fluoropolymer brushes are widely used to prevent nonspecific adsorption of commercial polymeric or biological materials due to their strongly hydrophobic character. Herein, a series of fluoropolymer brushes with different compositions, thicknesses and molecular architectures was prepared via surface-initiated atom transfer radical polymerization (ATRP). Subsequently, the antifouling properties of these fluoropolymer brushes against organic polymers were studied in detail using X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) measurements and polystyrene as a representative fouling polymer. Among all of the molecular architectures studied, homopolymerized methacrylate-based fluoropolymer brushes (PMAF17) show the best antifouling properties. Annealing the fluoropolymer brushes improves the antifouling property dramatically due to the reregulated surface composition. These fluoropolymer brushes can be combined with, e.g., micro- and nanostructuring and other advanced materials properties to yield even better long-term antifouling behavior under harsh environments.

  13. Evaluation of intestinal biopsies for pediatric enteropathy: a proposed immunohistochemical panel approach.

    Science.gov (United States)

    Martin, Brock A; Kerner, John A; Hazard, Florette K; Longacre, Teri A

    2014-10-01

    Congenital enteropathies are rare disorders with significant clinical consequences; however, definitive diagnosis based on morphologic assessment of duodenal biopsies with routine stains alone is often impossible. To determine the role of immunohistochemistry (IHC) in the evaluation for microvillous inclusion disease, congenital tufting enteropathy (intestinal epithelial dysplasia), and enteroendocrine cell dysgenesis, a series of duodenal biopsies from 26 pediatric patients with chronic/intractable diarrhea was retrospectively reviewed. IHC stains for CD10, EpCAM, chromogranin, and villin were performed on all biopsies, and the results were correlated with hematoxylin and eosin and ultrastructural findings using electron microscopy, when available. Biopsies from 2 patients diagnosed with microvillous inclusion disease at the time of original biopsy demonstrated diffuse CD10-positive cytoplasmic inclusions within enterocytes and normal expression of EpCAM and chromogranin. Biopsies from 3 patients, including 2 siblings with confirmed EPCAM mutations, demonstrated complete loss of EpCAM expression and normal expression of CD10 and chromogranin; electron microscopic evaluation revealed characteristic ultrastructural findings of tufting enteropathy. Biopsies from 1 patient with a confirmed NEUROG3 mutation demonstrated an absence of intestinal enteroendocrine cells by chromogranin staining, consistent with enteroendocrine cell dysgenesis. Four patients' biopsies displayed nonspecific staining patterns for CD10 and/or EpCAM with normal expression of chromogranin, and 16 patients' biopsies exhibited normal expression for all 3 markers. Villin stains demonstrated heterogenous brush border labeling with nonspecific cytoplasmic reactivity, a pattern variably present throughout the biopsy series. In conclusion, the routine use of an IHC panel of CD10, EpCAM, and chromogranin is warranted in patients meeting specific age and/or clinical criteria, as the morphologic findings

  14. Adhesion and friction properties of polymer brushes: Fluoro versus nonfluoro polymer brushes at varying thickness

    NARCIS (Netherlands)

    Bhairamadgi, N.S.; Pujari, S.P.; Leermakers, F.A.M.; Rijn, van C.J.M.; Zuilhof, H.

    2014-01-01

    A series of different thicknesses of fluoro poly(2,2,2-trifluoroethyl methacrylate) and its analogous nonfluoro poly(ethyl methacrylate) polymer brushes were prepared via surface-initiated ATRP (SI-ATRP) on Si(111) surfaces. The thiol-yne click reaction was used to immobilize the SI-ATRP initiator

  15. Border cell release

    DEFF Research Database (Denmark)

    Mravec, Jozef

    2017-01-01

    Plant border cells are specialised cells derived from the root cap with roles in the biomechanics of root growth and in forming a barrier against pathogens. The mechanism of highly localised cell separation which is essential for their release to the environment is little understood. Here I present...... in situ analysis of Brachypodium distachyon, a model organism for grasses which possess type II primary cell walls poor in pectin content. Results suggest similarity in spatial dynamics of pectic homogalacturonan during dicot and monocot border cell release. Integration of observations from different...... species leads to the hypothesis that this process most likely does not involve degradation of cell wall material but rather employs unique cell wall structural and compositional means enabling both the rigidity of the root cap as well as detachability of given cells on its surface....

  16. Stretching the Border

    DEFF Research Database (Denmark)

    Horstmann, Alexander

    2014-01-01

    In this paper, I hope to add a complementary perspective to James Scott’s recent work on avoidance strategies of subaltern mountain people by focusing on what I call the refugee public. The educated Karen elite uses the space of exile in the Thai borderland to reconstitute resources and to re-ent......-based organizations succeed to stretch the border by establishing a firm presence that is supported by the international humanitarian economy in the refugee camps in Northwestern Thailand....

  17. Defeating Cross Border Insurgencies

    Science.gov (United States)

    2007-12-14

    population of Pakistan, the Hindus with the Hindu in India and the Buddhists in Ladakh with the Tibetans . The cross border ethnic tie between Pakistan...Ladakh region by Buddhist .9 These demographics of IAK lay out the complexity of the issue. While there is an identifiable Kashmiri ethnicity, the three...Demographics IAK Population Muslim Hindu Buddhist Sikh Jammu 4,4 mio 29 % 65 % Less than 2% Less than 5% Kashmir 5,4 mio 96 % less than 4% None Less

  18. Distance, Borders, and Time

    DEFF Research Database (Denmark)

    Skillicorn, David; Walther, Olivier; Zheng, Quan

    is a combination of the physical geography of the target environment, and the mental and physical cost of following a seemingly random pattern of attacks. Focusing on the distance and time between attacks and taking into consideration the transaction costs that state boundaries impose, we wish to understand what......” of North and West Africa that depicts the permeability to violence. A better understanding of how location, time, and borders condition attacks enables planning, prepositioning, and response....

  19. Small Intestine Disorders

    Science.gov (United States)

    ... disease Crohn's disease Infections Intestinal cancer Intestinal obstruction Irritable bowel syndrome Ulcers, such as peptic ulcer Treatment of disorders of the small intestine depends on the cause.

  20. Brush head composition, wear profile, and cleaning efficacy: an assessment of three electric brush heads using in vitro methods.

    Science.gov (United States)

    Kaiser, Eva; Meyners, Michael; Markgraf, Dirk; Stoerkel, Ulrich; von Koppenfels, Roxana; Adam, Ralf; Soukup, Martin; Wehrbein, Heinrich; Erbe, Christina

    2014-01-01

    The objective of this research was to evaluate a current store brand (SB) brush head for composition/physical characteristics, Wear Index (WI), and cleaning efficacy versus the previous SB brush head refill design (SB control) and the Oral-B Precision Clean brush head (positive control, PC). This research consisted of three parts: 1) Analytical analysis using Fourier Transform Infrared (FT-IR) spectrometry to evaluate the chemical composition of the current SB brush head bristles relative to the SB control. In addition, physical parameters such as bristle count and diameter were determined. 2) Wear Index (WI) investigation to determine the Wear Index scores of in vitro-aged brush heads at four weeks (one month) and 13 weeks (three months) by a trained investigator. To "age" the brush heads, a robot system was used as a new alternative in vitro method to simulate aging by consumer use. 3) Robot testing to determine the cleaning performance of in vitro-aged brush heads, comparing one month-aged current SB brush heads with the SB control (one and three months-aged) and the PC brush heads (three months-aged) in a standardized fashion. 1) FT-IR analysis revealed that the chemical composition of the current and control SB refill brush heads is identical. In terms of physical parameters, the current SB brush head has 12% more bristles and a slightly oval brush head compared to the round brush head of the SB control. 2) Wear Index analysis showed there was no difference in the one month-aged current SB brush head versus the one month-aged SB control (1.67 vs. 1.50, p = 0.65) or versus the three months-aged PC brush head (1.67 vs. 1.50, p = 0.65). The one month-aged current SB brush head demonstrated statistically significantly less wear than the three months-aged SB control (1.67 vs. 2.67, p = 0.01). 3) Analysis of cleaning efficacy shows that the one month-aged current SB brush head had improved cleaning performance over the one month-aged SB control brush head (p < 0

  1. Metrics for border management systems.

    Energy Technology Data Exchange (ETDEWEB)

    Duggan, Ruth Ann

    2009-07-01

    There are as many unique and disparate manifestations of border systems as there are borders to protect. Border Security is a highly complex system analysis problem with global, regional, national, sector, and border element dimensions for land, water, and air domains. The complexity increases with the multiple, and sometimes conflicting, missions for regulating the flow of people and goods across borders, while securing them for national security. These systems include frontier border surveillance, immigration management and customs functions that must operate in a variety of weather, terrain, operational conditions, cultural constraints, and geopolitical contexts. As part of a Laboratory Directed Research and Development Project 08-684 (Year 1), the team developed a reference framework to decompose this complex system into international/regional, national, and border elements levels covering customs, immigration, and border policing functions. This generalized architecture is relevant to both domestic and international borders. As part of year two of this project (09-1204), the team determined relevant relative measures to better understand border management performance. This paper describes those relative metrics and how they can be used to improve border management systems.

  2. Effect of Frequency of Brushing Teeth on Plaque and Calculus Accumulation, and Gingivitis in Dogs.

    Science.gov (United States)

    Harvey, Colin; Serfilippi, Laurie; Barnvos, Donald

    2015-01-01

    The efficacy of brushing the teeth of beagle dogs in a randomized, controlled, blinded study design using a clearly-defined brushing technique was evaluated for 4 brushing frequencies: brushing daily, brushing every other day, brushing weekly and brushing every other week, compared with no brushing in a control group of dogs. All dogs were fed a standard dry kibble diet during the study. Standard plaque, calculus, and gingivitis indices were used to score the teeth. A 'clean tooth' model was used. No gingival or non-gingival lacerations or other signs of injury to oral tissues were found at the end of the 28 day trial period. Brushing more frequently had greater effectiveness in retarding accumulation of plaque and calculus, and reducing the severity of pre-existing gingivitis. Brushing daily or every other day produced statistically significant improved results compared with brushing weekly or every other week. Based on the results of this study, daily brushing is recommended.

  3. A brush stimulator for functional brain imaging.

    Science.gov (United States)

    Jousmäki, V; Nishitani, N; Hari, R

    2007-12-01

    To describe a novel non-magnetic hand-held device to stimulate various parts of the skin and to evaluate its performance in magnetoencephalographic (MEG) recordings. The hand-held part of the device consists of an optic fiber bundle that forms a small brush. Half of the fibers emit modulated red light and the other half detect the reflected light from the skin so that the brush-to-skin contact is detected by means of reflectance. Light tapping of the back of the hand at the innervation area of the radial nerve elicited clear responses in all 10 subjects studied, with the main deflections peaking 40-70 ms after the stimulus. The earliest responses, obtained with a higher number of averaged trials, peaked 27-28 ms after the tap to the left hand dorsum. Source analysis of the MEG signals indicated neuronal sources at the primary somatosensory (SI) cortex, with a clear somatotopical order for face vs. hand. The device seems feasible for both MEG and functional magnetic resonance imaging experiments to address functional anatomy of the human somatosensory system with a real-life like stimulation. Non-magnetic and artefact-free tactile stimulator with a selective stimulus offers new possibilities for experimental designs to study the human mechanoreceptor system.

  4. Brush seal shaft wear resistant coatings

    Science.gov (United States)

    Howe, Harold

    1995-03-01

    Brush seals suffer from high wear, which reduces their effectiveness. This work sought to reduce brush seal wear by identifying and testing several industry standard coatings. One of the coatings was developed for this work. It was a co-sprayed PSZ with boron-nitride added for a high temperature dry lubricant. Other coatings tested were a PSZ, chrome carbide and a bare rotor. Testing of these coatings included thermal shocking, tensile testing and wear/coefficient of friction testing. Wear testing consisted of applying a coating to a rotor and then running a sample tuft of SiC ceramic fiber against the coating. Surface speeds at point of contact were slightly over 1000 ft/sec. Rotor wear was noted, as well as coefficient of friction data. Results from the testing indicates that the oxide ceramic coatings cannot withstand the given set of conditions. Carbide coatings will not work because of the need for a metallic binder, which oxidizes in the high heat produced by friction. All work indicated a need for a coating that has a lubricant contained within itself and the coating must be resistant to an oxidizing environment.

  5. Nanomechanical properties of polymer brushes by colloidal AFM probes

    NARCIS (Netherlands)

    Kutnyanszky, E.; Vancso, Gyula J.

    2012-01-01

    Nanomechanical properties of end grafted polymer layers were studied by AFM based, colloidal probe compression measurements. Zwitterionic poly(sulfobetaine methacrylate) (PSBMA) brush was grafted from planar Si surface and poly(methyl methacrylate) (PMAA) brush was grown on colloidal probe by

  6. Current control by a homopolar machine with moving brushes

    International Nuclear Information System (INIS)

    Vogel, H.

    1978-01-01

    The equation for TNS Doublet's E-coil circuit with moving brush homopolar machine is integrated in the flux of the homopolar for a monotonically increasing current function extending beyond the current reversal into the burn period. The results show that the moving brush feature is not useful for controlling the burn

  7. Switchable adhesion and friction by stimulus responsive polymer brushes

    NARCIS (Netherlands)

    Yu, Yunlong

    2017-01-01

    Controlling friction and adhesion is relevant in nature and in our daily life. Such control can be achieved using stimulus responsive end-anchored polymers forming a brush. These brushes can adapt their physicochemical properties upon changing the surrounding environments, such as temperature,

  8. Carbazole functionalized isocyanide brushes in heterojunction photovoltaic devices

    NARCIS (Netherlands)

    Lim, E.; Gao, F.; Schwartz, E.; Schwartz, E.; Cornelissen, Jeroen Johannes Lambertus Maria; Nolte, R.J.M.; Rowan, A.E.; Greenham, N.C.; Do, L.M.

    2012-01-01

    In this work, carbazole-containing polyisocyanide (PIACz) brushes were used for photovoltaic devices. A photovoltaic device was fabricated on top of the brushes by spin-coating a suitable acceptor and evaporating an Al cathode. Devices with a poly(N-vinylcarbazole) (PVK) bulk polymer were also

  9. Wildlife response to brush management: a contemporary evaluation

    Science.gov (United States)

    Brush management has been widely practiced with the general intent of curtailing or reversing the proliferation of shrubs and trees in grasslands and savannas. The traditional aim of brush management has been to increase livestock forage or to improve water yield. Its potential role for restoring h...

  10. 75 FR 18237 - Natural Bristle Paint Brushes From China

    Science.gov (United States)

    2010-04-09

    ... COMMISSION Natural Bristle Paint Brushes From China AGENCY: United States International Trade Commission... duty order on natural bristle paint brushes from China. SUMMARY: The Commission hereby gives notice....C. 1675(c)(5)) to determine whether revocation of the antidumping duty order on natural bristle...

  11. 75 FR 21347 - Natural Bristle Paint Brushes From China

    Science.gov (United States)

    2010-04-23

    ... COMMISSION Natural Bristle Paint Brushes From China AGENCY: United States International Trade Commission. ACTION: Scheduling of a full five-year review concerning the antidumping duty order on natural bristle... whether revocation of the antidumping duty order on natural bristle paint brushes from China would be...

  12. 75 FR 39706 - Natural Bristle Paint Brushes From China

    Science.gov (United States)

    2010-07-12

    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Natural Bristle Paint Brushes From China AGENCY: United States International Trade Commission... the antidumping duty order on natural bristle paint brushes from China (75 FR 21347, April 23, 2010...

  13. 21 CFR 868.5795 - Tracheal tube cleaning brush.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Tracheal tube cleaning brush. 868.5795 Section 868.5795 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5795 Tracheal tube cleaning brush. (a...

  14. Surface grafted polymer brushes: potential applications in dengue biosensors

    International Nuclear Information System (INIS)

    Baratela, Fernando Jose Costa; Higa, Olga Zazuco; Faria, Henrique Antonio Mendonca de; Queiroz, Alvaro Antonio Alencar de

    2013-01-01

    A polymer brush membrane-based ultrasensitive biosensor for dengue diagnosis was constructed using poly(hydroxyethyl methacrylate) (PHEMA) brushes immobilized onto low density polyethylene (LDPE) films. LDPE surface films were initially modified by Ar + ion irradiation to activate the polymer surface. Subsequently, graft polymerization of 2-hydroxyethyl methacrylate onto the activated LDPE surface was carried out under aqueous conditions to create patterned polymer brushes of PHEMA. The grafted PHEMA brushes were characterized by Fourier transform-infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and contact angle analysis. The SEM observations showed that selective surface activation with Ar+ implantation and graft polymerization on the selectively activated surface had occurred. The PHEMA brushes were electrically characterized in the presence of concentrations of human immunoglobulin (IgG). The proposed amperometric biosensor was successfully used for determination of IgG in physiologic samples with excellent responses. (author)

  15. Surface grafted polymer brushes: potential applications in dengue biosensors

    Energy Technology Data Exchange (ETDEWEB)

    Baratela, Fernando Jose Costa; Higa, Olga Zazuco, E-mail: ozahiga@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Faria, Henrique Antonio Mendonca de; Queiroz, Alvaro Antonio Alencar de, E-mail: alencar@unifei.edu.br [Universidade Federal de Itajuba (UNIFEI), Itajuba, MG (Brazil). Instituto de Fisica e Quimica

    2013-07-01

    A polymer brush membrane-based ultrasensitive biosensor for dengue diagnosis was constructed using poly(hydroxyethyl methacrylate) (PHEMA) brushes immobilized onto low density polyethylene (LDPE) films. LDPE surface films were initially modified by Ar{sup +} ion irradiation to activate the polymer surface. Subsequently, graft polymerization of 2-hydroxyethyl methacrylate onto the activated LDPE surface was carried out under aqueous conditions to create patterned polymer brushes of PHEMA. The grafted PHEMA brushes were characterized by Fourier transform-infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and contact angle analysis. The SEM observations showed that selective surface activation with Ar+ implantation and graft polymerization on the selectively activated surface had occurred. The PHEMA brushes were electrically characterized in the presence of concentrations of human immunoglobulin (IgG). The proposed amperometric biosensor was successfully used for determination of IgG in physiologic samples with excellent responses. (author)

  16. Tooth-brushing behaviour in 6-12 year olds.

    Science.gov (United States)

    Sandström, Anna; Cressey, Janet; Stecksén-Blicks, Christina

    2011-01-01

    A common clinical finding is that many schoolchildren display a nonacceptable oral hygiene. To evaluate the tooth-brushing behaviour in children aged 6-12 years. The study used a cross-sectional descriptive design. Children aged 6, 8, 10, and 12 years in an elementary school in a middle class area in Umeå, a city in northern Sweden, were invited and 82 (82%) consented. Visible plaque on buccal surfaces of incisors and canines was recorded from photographs of the participant's teeth before and after brushing using the scores of the Green and Vermillion Oral Hygiene Index. Brushing technique was recorded with a video camera. A questionnaire was used to collect data about oral hygiene habits at home. The ratio between the sum of plaque scores after and before brushing was statistically significantly higher in the 6-year-old group compared with the 10-year olds, (P brushing and the ratio between the sum of plaque scores after and before brushing (r = -0.31, P 0.05). Six-year olds spent statistically significantly less time for brushing than older children (P brushing was poor and averaged 19% for 6-year olds and 30% for older children. The results of brushing for children aged 8-12 years could benefit from increasing tooth-brushing time. Children could be given an increasing responsibility from 7 to 8 year of age but parental help is motivated up to 10 years of age. © 2010 The Authors. International Journal of Paediatric Dentistry © 2010 BSPD, IAPD and Blackwell Publishing Ltd.

  17. Does knowledge have borders?

    DEFF Research Database (Denmark)

    Tange, Hanne

    International education is often promoted through discourses of openness, cross-cultural relationship-building and global understanding. But how inclusive is the kind of knowledge offered in the so-called “global” learning environments? The paper explores possible limits to knowledge production a...... and represented within their course and academic discipline. We will present in the paper the preliminary findings of our research, pointing to some of the visible and invisible borders that one finds within the field of global education....

  18. Business, brokers and borders

    DEFF Research Database (Denmark)

    Walther, Olivier

    2015-01-01

    in two border regions between Niger, Nigeria, and Benin. In a business environment where transaction costs are extremely high, we find that decentralized networks are well adapted to the various uncertainties induced by long-distance trade. We also find that long-distance trade relies both on the trust...... and cooperation shared among local traders, and on the distant ties developed with foreign partners from a different origin, religion or culture. Studying the spatial structure of trade networks, we find that in those markets where trade is recent and where most of the traders are not native of the region...

  19. Efficiency of the surgical washing of hands with brush and without brush

    Directory of Open Access Journals (Sweden)

    Fresia Canales Carmona

    2013-10-01

    Full Text Available The purpose of this article is to establish the answer to a clinical question regarding the effectiveness ofpreoperative hygiene with hand washing brush or without it. This first technique has been performed on the skinto reduce transient bacteria and to inhibit the growth of resident microorganisms as a common and required actbefore any surgical procedure. Despite this measure and others such as prophylactic antibiotics, the mainoperative complication continues to be the surgical wound infection. Today, it is as prevalent as in the past withthe consequent negative effects derived from it, both for the institutions and for patients. Being controversialtoday which one is the most effective and safe surgical hand washing method for the binomial: professionalsurgical team/ patient, this study is done under the criteria of the Evidence-Based Nursing.A question was builtin PICO format (Personal, Intervention, Comparison and Outcome. After this is done, continues informationsearch in the databases GOOGLE ACADÉMICO, Pub Med, Cochrane y Base de Datos para la Investigación enEnfermería (BDIE We obtained 20 articles related to the topic of them 8, which fulfilled the set CASPe criteriato answer the clinical question, were analyzed. We conclude that washing hands with a brush is equally effectiveas without brush technique in terms of decreased of the superficial skin bacterial flora, although this technique hasadvantages over the traditional practice.

  20. three intelligence methodologies for border defence and border

    African Journals Online (AJOL)

    Administrator

    The main security problem that any state faces today is protecting its citizens in countering organised crime and terrorism. Wars between states are less frequent than in previous eras. Border defence and border security are distinct missions requiring different forces with different training and different equipment.

  1. Cross-border agglomeration benefits

    NARCIS (Netherlands)

    Smit, Martijn J.

    2017-01-01

    Spatial correlations exist for many economic phenomena. We also know such interactions are typically weaker across country borders than within countries, due to institutional, infrastructural or cultural factors. However, in spatial econometric analyses, the effect of borders is rarely taken into

  2. Oficios de frontera - Border trades

    Directory of Open Access Journals (Sweden)

    Santos López, Pascual

    2008-06-01

    Full Text Available Thanks to the efforts of Alfaqueques many captives were recovered from Cieza, following the violent riot Nazari in 1477. Other border trades as ejeas, almocadenes and adalides were known for centuries along the Andalusian border between Murcia and Granada.

  3. Border mythology: Turner and modernity

    Directory of Open Access Journals (Sweden)

    Jorge E. Brenna B.

    2011-07-01

    Full Text Available Modernity has been creating spaces, new boundaries and borders, as metaphysical, mythological and symbolic marks of physical and imaginary territories. Modern space and its borders are metaphors, boundaries that are created, walls that rise to identify with some and categorize others. In this short paper we want to approach the problem of the transformation of the idea of border (geographical, cultural, symbolic, etc., for a reflection on the transformations of that civilized obsession called border. The border has always been a reference in facing the identities, names, symbols, different imaginary: it is more confrontational line between two otherness. From the previous framework, we reflect on Turnerian mythology, as we believe that behind the creation of the imagination of the northern border is the mythical vision of the American frontier as ideological canon that explains and confirms the presence of the white race in a border re–made in the image and likeness of the “American Dream”. Frederick Turner’s reflection on the role of the frontier in American history is not only the study of the importance of progress towards the West but –even more so, is the analysis of meaning that had the American frontier as a historical process that ended in 1893, as Turner said, but rather extended into the twentieth century and continues to constantly shaping the process of territorialization of the border.

  4. Brush/gold nanoparticle hybrids: effect of grafting density on the particle uptake and distribution within weak polyelectrolyte brushes.

    Science.gov (United States)

    Christau, Stephanie; Möller, Tim; Yenice, Zuleyha; Genzer, Jan; von Klitzing, Regine

    2014-11-04

    The effect of the brush grafting density on the loading of 13 nm gold nanoparticles (AuNPs) into stimuli-responsive poly(N,N-(dimethylamino ethyl) methacrylate) (PDMAEMA) brushes anchored to flat impenetrable substrates is reported. Atom-transfer radical polymerization (ATRP) is used to grow polymer brushes via a "grafting from" approach from a 2-bromo-2-methyl-N-(3-(triethoxysilyl) propyl) propanamide (BTPAm)-covered silicon substrate. The grafting density is varied by using mixtures of initiator and a "dummy" molecule that is not able to initiate polymerization. A systematic study is carried out by varying the brush grafting density while keeping all of the other parameters constant. X-ray reflectivity is a suitable tool for investigating the spatial structure of the hybrid, and it is combined with scanning electron microscopy and UV/vis spectroscopy to study the particle loading and interpenetration of the particles within the polymer brush matrix. The particle uptake increases with decreasing grafting density and is highest for an intermediate grafting density because more space between the polymer chains is available. For very low grafting densities of PDMAEMA brushes, the particle uptake decreases because of a lack of the polymer matrix for the attachment of particles. The structure of the surface-grafted polymer chains changes after particle attachment. More water is incorporated into the brush matrix after particle immobilization, which leads to a swelling of the polymer chains in the hybrid material. Water can be removed from the brush by decreasing the relative humidity, which leads to brush shrinking and forces the AuNPs to get closer to each other.

  5. On the collapse transition of a polymer brush: the case of lateral mobility

    NARCIS (Netherlands)

    Leermakers, F.A.M.; Egorov, S.A.

    2013-01-01

    We consider a polymer brush composed of end-grafted polymer chains. Classical theory advocates that a worsening of the solvent quality results in a smooth decrease of the brush height from a swollen to a dense brush. We report that a homogeneous brush under poor solvent conditions can have a

  6. Coronavirus Attachment and Replication

    Science.gov (United States)

    1988-03-28

    receptors on intestinal brush border membranes from normal host species were developed for canine (CCV), feline (FIPV), porcine ( TGEV ), human (HCV...229E), and bovine (BCV) coronaviruses. The antigenically related coronaviruses, CCV, FIPV, TGEV , and HCV -229E bound to intestinal brush border...Forest virus SPA staphylococcal protein A STM sample treatment mix TCA trichloroacetic acid TCV turkey corona virus TGEV transmissible

  7. Chemical coding and chemosensory properties of cholinergic brush cells in the mouse gastrointestinal and biliary tract

    Directory of Open Access Journals (Sweden)

    Burkhard eSchütz

    2015-03-01

    Full Text Available The mouse gastro-intestinal and biliary tract mucosal epithelia harbor choline acetyltransferase (ChAT-positive brush cells with taste cell-like traits. With the aid of two transgenic mouse lines that express green fluorescent protein (EGFP under the control of the ChAT promoter (EGFPChAT and by using in situ hybridization and immunohistochemistry we found that EGFPChAT cells were clustered in the epithelium lining the gastric groove. EGFPChAT cells were numerous in the gall bladder and bile duct, and found scattered as solitary cells along the small and large intestine. While all EGFPChAT cells were also ChAT-positive, expression of the high-affinity choline transporter (ChT1 was never detected. Except for the proximal colon, EGFPChAT cells also lacked detectable expression of the vesicular acetylcholine transporter (VAChT. EGFPChAT cells were found to be separate from enteroendocrine cells, however they were all immunoreactive for cytokeratin 18 (CK18, transient receptor potential melastatin-like subtype 5 channel (TRPM5, and for cyclooxygenases 1 (COX1 and 2 (COX2. The ex vivo stimulation of colonic EGFPChAT cells with the bitter substance denatonium resulted in a strong increase in intracellular calcium, while in other epithelial cells such an increase was significantly weaker and also timely delayed. Subsequent stimulation with cycloheximide was ineffective in both cell populations. Given their chemical coding and chemosensory properties, EGFPChAT brush cells thus may have integrative functions and participate in induction of protective reflexes and inflammatory events by utilizing ACh and prostaglandins for paracrine signaling.

  8. Microsensors for border patrol applications

    Science.gov (United States)

    Falkofske, Dwight; Krantz, Brian; Shimazu, Ron; Berglund, Victor

    2005-05-01

    A top concern in homeland security efforts is the lack of ability to monitor the thousands of miles of open border with our neighbors. It is not currently feasible to continually monitor the borders for illegal intrusions. The MicroSensor System (MSS) seeks to achieve a low-cost monitoring solution that can be efficiently deployed for border patrol applications. The modifications and issues regarding the unique requirements of this application will be discussed and presented. The MicroSensor System was developed by the Defense Microelectronics Activity (DMEA) for military applications, but border patrol applications, with their unique sensor requirements, demand careful adaptation and modification from the military application. Adaptation of the existing sensor design for border applications has been initiated. Coverage issues, communications needs, and other requirements need to be explored for the border patrol application. Currently, border patrol has a number of deficiencies that can be addressed with a microsensor network. First, a distributed networked sensor field could mitigate the porous border intruder detection problem. Second, a unified database needs to be available to identify aliens attempting to cross into the United States. This database needs to take unique characteristics (e.g. biometrics, fingerprints) recovered from a specialized field unit to reliably identify intruders. Finally, this sensor network needs to provide a communication ability to allow border patrol officers to have quick access to intrusion information as well as equipment tracking and voice communication. MSS already addresses the sensing portion of the solution, including detection of acoustic, infrared, magnetic, and seismic events. MSS also includes a low-power networking protocol to lengthen the battery life. In addition to current military requirements, MSS needs a solar panel solution to extend its battery life to 5 years, and an additional backbone communication link

  9. The study of functional parameter of the electric coal brushes

    Directory of Open Access Journals (Sweden)

    Claudia Staşac

    2008-05-01

    Full Text Available These paper present a study about the analyzeof the functional parameters of the electrical coal brush.The analyze was made with an experimental device, andthe results was prelucrate in MathCAD software.

  10. Anthrax in Vintage Animal-hair Shaving Brushes

    Centers for Disease Control (CDC) Podcasts

    2017-08-08

    Dr. Kate Hendricks, a CDC anthrax expert, discusses anthrax in vintage shaving brushes.  Created: 8/8/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/8/2017.

  11. Electroosmotic Flow in Mixed Polymer Brush-Grafted Nanochannels

    Directory of Open Access Journals (Sweden)

    Qianqian Cao

    2016-12-01

    Full Text Available Mixed polymer brush-grafted nanochannels—where two distinct species of polymers are alternately grafted on the inner surface of nanochannels—are an interesting class of nanostructured hybrid materials. By using a coarse-grained molecular dynamics simulation method, we are able to simulate the electrokinetic transport dynamics of the fluid in such nanochannels as well as the conformational behaviors of the mixed polymer brush. We find that (1 the brush adopts vertically-layered and longitudinally-separated structures due to the coupling of electroosmotic flow (EOF and applied electric field; (2 the solvent quality affects the brush conformations and the transport properties of the EOF; (3 the EOF flux non-monotonically depends on the grafting density, although the EOF velocity in the central region of the channel monotonically depends on the grafting density.

  12. Switchable Adhesion Properties From Low and High Tg Polymeric Brushes

    Science.gov (United States)

    Retsos, Haris; Tran, Yvette; Gorodyska, Ganna; Kiriy, Anton; Stamm, Manfred; Creton, Costantino

    2006-03-01

    We investigated the adhesive properties of mono-component and bi-component polymeric brushes chemically grafted on silicon wafers from end-functionalized hydrophilic and/or hydrophobic chains by using the technically simple `grafting to' method. The charge state and the molecular organization of high Tg brushes could be varied reversibly by exposure to appropriate solvents or by varying the grafting density. Adhesive properties were tested against soft pressure-sensitive-adhesives (hydrophobic & hydrophilic) with a probe method. In the case of low Tg brushes, an increase in contact time could selectively improve the adhesion with the soft hydrophobic or hydrophilic adhesive layer. This is due to reorganization of the interface at the molecular scale leading to the formation of entanglements or favorable interactions between the polymer brush and the polymers in the soft adhesive.

  13. Astronauts Culbertson and Bursch brush their teeth on Discovery's middeck

    Science.gov (United States)

    1993-01-01

    Astronauts Frank L. Culbertson (right), mission commander, and Daniel W. Bursch, mission specialist, brush their teeth on Discovery's middeck. Two sleep restraints form part of the backdrop for the photograph.

  14. Intestinal phosphate absorption is mediated by multiple transport systems in rats.

    Science.gov (United States)

    Candeal, Eduardo; Caldas, Yupanqui A; Guillén, Natalia; Levi, Moshe; Sorribas, Víctor

    2017-04-01

    Apical inorganic phosphate (P i ) transport in the small intestine seems to be mainly mediated by the sodium/P i cotransporter NaPi2b. To verify this role, we have studied the combined effects of pH, phosphonoformate, and P i deprivation on intestinal P i transport. Rats were fed, ad libitum, three fodders containing 1.2, 0.6, or 0.1% P i for 1, 5, or 10 days. P i deprivation (0.1%) increased both sodium-activated and sodium-independent P i transport in brush-border membrane vesicles from the duodenum and jejunum for all three times. Alkaline pH inhibited P i transport, despite the increasing concentration of [Formula: see text] (NaPi2b substrate), whereas acidity increased transport when the concentration of the PiT1/PiT2 substrate, [Formula: see text], was at its highest. The effect of P i deprivation was maximal at acid pH, but both basal and upregulated transport were inhibited (70%) with phosphonoformate, an inhibitor of NaPi2b. PiT2 and NaPi2b protein abundance increased after 24 h of P i deprivation in the duodenum, jejunum, and ileum, whereas PiT1 required 5-10 days in the duodenum and jejunum. Therefore, whereas transporter expressions are partially correlated with P i transport adaptation, the pH effect precludes NaPi2b, and phosphonoformic acid precludes PiT1 and PiT2 as the main transporters. Transport and transporter expression were also inconsistent when feeding was limited to 4 h daily, because the 1.2% P i diet paradoxically increased P i transport in the duodenum and jejunum, but NaPi2b and PiT1 expressions only increased with the 0.1% diet. These findings suggest the presence of a major transporter that carries [Formula: see text] and is inhibited by phosphonoformate. NEW & NOTEWORTHY The combined effects of dietary inorganic phosphate (P i ) content, pH, and phosphonoformate inhibition suggest that the resulting apical P i transport in the small intestine cannot be fully explained by the presence of NaPi2b, PiT1, or PiT2. We provide evidence of

  15. Macroion induced dehydration of weak polyelectrolyte brushes

    Science.gov (United States)

    Zheng, Zhongli; Zhu, Y. Elaine

    2014-03-01

    The interaction of macroions, including polyelectrolytes, DNAs, and proteins, with polymer and cellular surfaces is critically related to many biomolecular activities, such as protein adsorption and DNA hybridization at probe surfaces. In an experimental approach to examine the macroion electrostatic interaction with a polymer surface while minimizing the long-debated hydrophobic interaction, we study the interaction of molybdenum-based inorganic polyoxometalate (POM) nanoclusters carrying 42 negative charges as model hydrophilic macroions with surface-tethered poly-2-vinylpyridine (P2VP) brushes immersed in aqueous solutions. By AFM, QCM, and contact goniometer, we have observed the collapse of P2VP chains by adding POM macroions at a constant pH. Surprisingly, added POM macroions can cause the shift of swollen-to-collapse transition pH to a lower value, in contrast to the shift to high pH value by adding simple monovalent salts. At sufficiently high POM concentration, a stable POM-P2VP composite layer, showing little dependence on solution pH and additional salts, can be formed, suggesting a simple route to construct meso-porous polymer membranes.

  16. Polyelectrolyte brushes in mixed ionic medium studied via intermolecular forces

    Science.gov (United States)

    Farina, Robert; Laugel, Nicolas; Pincus, Philip; Tirrell, Matthew

    2011-03-01

    The vast uses and applications of polyelectrolyte brushes make them an attractive field of research especially with the growing interest in responsive materials. Polymers which respond via changes in temperature, pH, and ionic strength are increasingly being used for applications in drug delivery, chemical gating, etc. When polyelectrolyte brushes are found in either nature (e.g., surfaces of cartilage and mammalian lung interiors) or commercially (e.g., skin care products, shampoo, and surfaces of medical devices) they are always surrounded by mixed ionic medium. This makes the study of these brushes in varying ionic environments extremely relevant for both current and future potential applications. The polyelectrolyte brushes in this work are diblock co-polymers of poly-styrene sulfonate (N=420) and poly-t-butyl styrene (N=20) which tethers to a hydrophobic surface allowing for a purely thermodynamic study of the polyelectrolyte chains. Intermolecular forces between two brushes are measured using the SFA. As multi-valent concentrations are increased, the brushes collapse internally and form strong adhesion between one another after contact (properties not seen in a purely mono-valent environment).

  17. Controlling the swelling and wettability of weak polyelectrolyte brushes

    Science.gov (United States)

    Gurtowski, Richard; Jing, Benxin; Zhu, Elaine

    2011-03-01

    Weak polyelectrolytes (PE) of tunable ionization shows great potential as ``smart'' polymer materials for diverse applications from drug delivery to energy storage. However, the conformational dynamics of surfaced-tethered weak PE chains remain inadequately understood due to the complexity of their dynamic charge states in response to solvation and surface immobilization conditions. In this work, we investigate the wetting and swelling characteristics of poly(2-vinyl pyridine) (P2VP) brushes grafted to a gold substrate by AFM and water contact angle measurements. We observe the collapse of P2VP brushes, accompanied with increased surface hydrophobicity, as increasing solution pH across a critical transition pH, which is considerably lower than the pKa of free P2VP chains in bulk solution. Surprisingly, the broadness of the transition pH range shows a strong dependence with brush thickness, but not grafting density, suggesting a distribution of chain ionization along grafted P2VP brushes. We further manipulate P2VP brush structures by applying ac-electric fields across the brushes to make tunable and switchable polymer surfaces.

  18. Cues to Action as Motivators for Children's Brushing.

    Science.gov (United States)

    Walker, Kimberly K; Steinfort, Erin L; Keyler, Maria J

    2015-01-01

    Dental caries is the most common chronic childhood disease. Home self-care procedures are the most important strategies to prevent tooth decay. Brushing is the most important single intervention for the prevention of tooth decay, yet compliance is not practiced and there is limited understanding of children's behavioral decisions. Guided by the Health Belief Model, this study consisted of eight focus groups with children in the second through fifth grades at three different socioeconomic-level school districts to determine the cues to action that are motivating or can motivate their brushing behavior. Results indicated children are primarily motivated to brush for aesthetic reasons, mainly due to viewed media pictures of "perfect" teeth. Other less commonly expressed motivations for brushing stemmed from interpersonal connections, such as relatives with dentures. Social media, on the other hand, played a key role in some children's understanding of more advanced oral health connections such as links between cardiovascular and oral disease, and smoking and oral cancer. These links were viewed as threatening to children to motivate better brushing. Additionally, the study found that home computers can be used as an external motivator to deliver tailored messages to encourage better brushing.

  19. Polyelectrolyte brushes at the air/water interface

    International Nuclear Information System (INIS)

    Matsuoka, Hideki

    2005-01-01

    The nanostructure of amphiphilic diblock copolymer monolayer on water surface was investigated by in situ X-ray and neutron reflectivity. The diblock copolymers used have a long hydrophobic chain and a polyelectrolyte chain as a hydrophilic block. The monolayer was found not to have a simple double layer structure (hydrophobic layer / hydrophilic (carpet) layer) but to have a three layer structure consisting of hydrophobic layer, hydrophilic dense carpet layer, and polyelectrolyte brush layer when the polyelectrolyte block is long enough and the surface pressure (i.e. brush density) is high enough. The transition from carpet only to carpet/brush double layer structure in hydrophilic layer was observed as a function of polyelectrolyte chain length, the surface pressure. When the hydrophilic chain is a weak polyelectrolyte, the monolayer first expanded and then shrunk with increasing salt concentration in the subphase. For the strongly ionic polyelectrolyte, the monolayer structure was not affected by salt addition up to ∼0.2 M. These observations can be explained by a balance of the charged state of the brush chain, an electrostatic repulsion between brush chains and salt concentration in the brush layer

  20. What is the best predictor for oral cleanliness after brushing? Results from an observational cohort study.

    Science.gov (United States)

    Harnacke, Daniela; Winterfeld, Tobias; Erhardt, Jörg; Schlueter, Nadine; Ganss, Carolina; Margraf-Stiksrud, Jutta; Deinzer, Renate

    2015-01-01

    Brushing performance is an important factor for brushing success. Thus, observing brushing performance might help to explain deficits in oral hygiene. However, it is unknown how brushing behavior observed at one time relates to brushing capabilities observed at another time. The authors assessed the predictive validity of video-observed habitual brushing behavior for the capability to achieve oral cleanliness several weeks later. Study participants (N = 101) were video-recorded while cleaning their teeth. Two independent, calibrated examiners assessed brushing duration, evenness of distribution of brushing time across areas of the mouth as one indicator of brushing systematics, and duration of specific brushing movements. Weeks later (mean: 6.4 weeks; range: 1 to 24 weeks), 70 participants were asked to remove plaque to the best of their ability, and degree of oral cleanliness was assessed immediately afterward. A forward regression analysis was performed to assess the predictive values of brushing parameters. Regression analysis revealed that evenness of distribution of brushing time and duration of circling movements explained 20.8% of variance of oral cleanliness (P brushing time and duration of circling movements are aspects of observed habitual brushing behavior that predict brushing capabilities in terms of oral cleanliness.

  1. Firemen without borders

    CERN Multimedia

    2005-01-01

    Fire knows no borders and neither should the tools for fighting it. It was with this aim in mind that delegates from 14 different countries came to CERN at the beginning of April to take part in the twentieth of a series of twice-yearly international conferences organised by the Federation of European Union Fire Officer Associations (FEU). This latest conference allowed participants to keep abreast of new developments with a view to improving the safety techniques used in their own countries. The first in the series was held in Tampere, Finland, in 1994. The FEU network's objective is to harmonise safety policies and modernise the fire-fighting programme. In particular, it aims to develop an international system for testing hotels' fire alarm systems and to improve language learning in all countries' fire-fighting services. "We want authorities throughout Europe to be aware of the importance of a good joint fire-prevention policy in order to avoid catastrophes such as the fire that destroyed Madrid's Winds...

  2. Intestinal pseudo-obstruction

    Science.gov (United States)

    Primary intestinal pseudo-obstruction; Acute colonic ileus; Colonic pseudo-obstruction; Idiopathic intestinal pseudo-obstruction; Ogilvie syndrome; Chronic intestinal pseudo-obstruction; Paralytic ileus - pseudo-obstruction

  3. Border Security: Barriers Along the U.S. International Border

    Science.gov (United States)

    2009-03-16

    Nogales, AZ; Naco , AZ; Douglas, AZ; and El Paso, TX. In 1996, Congress passed the Illegal Immigration Reform and Immigrant Responsibility Act... Naco , AZ; Douglas, AZ; and El Paso, TX.80 In a 1999 study which was commissioned by the INS and performed under a Memorandum of Understanding, the...Naturalization Service, Final Environmental Assessment U.S. Border Patrol Temporary Vehicle Barriers Naco and Douglas, Arizona, November 2002. Border Security

  4. Radiological manifestations of intestinal tuberculosis

    International Nuclear Information System (INIS)

    Im, Jae Hoon

    1974-01-01

    Radiological findings of 87 cases of intestinal tuberculosis are analyzed and presented. The diagnosis was based on histopathology in 29 cases, and on clinical ground and radiological findings in 58 cases. The radio of male and female patients was 4:6, and peak incidence is between 10 and 30. Abdominal pain, diarrhea, weight loss, fever and general weakness are frequent symptoms, and tenderness of abdomen, ascites with abdominal distension, malnutrition and emaciation are frequent signs of the patients. Laboratory investigation reveal anemia, raised ESR, hypoalbuminaemia and positive occult blood reaction in the stool in most of the patients. Chest film show activity pulmonary tuberculosis in only 1/3 patients. There is no pathognomonic radiological findings in intestinal tuberculosis and their manifestations are protean, and differentiation from other inflammatory diseases and malignant tumors in gastrointestinal tract is very difficult on radiological ground alone. However, in patients with complaining vague abdominal symptoms and signs, the radiological diagnosis is most certain means in the decision of existence of organic lesion and suggestion of tuberculosis in the gastrointestinal tract and its extent as yet. Multiplicity of the lesion, involvement of adjacent organ such as peritoneum or mesenteric lymph nodes, typical nodularity or irregularity of mesenteric border and existence of active pulmonary tuberculosis are the suggestive findings of intestinal tuberculosis. In the diagnosis of inflammatory disease or malignant tumor of gastrointestinal tract, the possibility of tuberculosis should be borne in mind, and vice versa

  5. Intestinal myiasis

    Directory of Open Access Journals (Sweden)

    U S Udgaonkar

    2012-01-01

    Full Text Available Purpose: Intestinal myiasis is a condition when the fly larvae inhabit the gastrointestinal tract and are passed out in faeces. This type of infestation results when eggs or larvae of the fly, deposited on food are inadvertently taken by man. They survive the unfavourable conditions within the gastrointestinal tract and produce disturbances, which may vary from mild to severe. The condition is not uncommon and is often misdiagnosed as pinworm infestation. Correct diagnosis by the clinical microbiologist is important to avoid unnecessary treatment. Materials and Methods: We had 7 cases of intestinal myiasis. In 2 cases the larvae were reared to adult fly in modified meat and sand medium (developed by Udgaonkar. This medium is simple and can be easily prepared in the laboratory. Results: Of the 7 larvae, 5 were Sarcophaga haemorrhoidalis, 1 Megaselia species and 1 was identified as Muscina stabulans. Conclusions: S. haemorrhoidalis was the commonest maggot involved. A high index of suspicion is required for clinical diagnosis when the patient complains of passing wriggling worms in faeces for a long period without any response to antihelminthics. The reason for long duration of illness and recurrence of infestation is baffling. The nearest to cure was colonic wash. We feel prevention is of utmost importance, which is to avoid eating food articles with easy access to flies.

  6. Typhoid Intestinal Perforation: 24 Perforations in One Patient

    African Journals Online (AJOL)

    There were 24 perforations (21 in terminal ileum and 3 in cecum) present in distal 35‑40 cm of terminal ileum reaching up to ileocecal junction and the Cecum on anti‑mesenteric border as shown in. Figures 1 and 2. Resection of the perforated intestinal segment with ileo‑transverse anastomosis (side‑to‑side) with proximal.

  7. Evaluation of several brushing motion combinations in relation to plaque-removing efficacy with Oral-B CrossAction Power: a professional brushing study.

    Science.gov (United States)

    Versteeg, P A; Timmerman, M F; Paraskevas, S; van der Weijden, G A

    2006-11-01

    The aim of this study was to evaluate the additional effect of a newly developed battery-operated brush Oral-B CrossAction Power with a hybrid brush head design (CAPB). The brush combines an oscillating/rotating part, a PowerHead(R), with a non-moving part with CrissCross bristles. It was compared with a manual control toothbrush Butler GUM 311 (CTB). Thirty subjects were requested not to brush their teeth 48 h prior to the examination, when plaque removal efficacy was assessed by scoring plaque before and after brushing. Plaque was assessed according to the Silness & Loë Index at six sites per tooth. Subjects were brushed by a dentist using one of the four randomly chosen procedures of brushing in each quadrant. The CAPB was used with three different modes of brushing each in different randomly chosen quadrants, with the manual toothbrush being used in the remaining quadrant as a control. The baseline plaque levels ranged from 1.69 to 1.74 and the end levels ranged from 0.39 to 0.45. In terms of percentage, the results with the four procedures run from 75% to 79%. These differences between the battery brush and manual brush irrespective of the brushing mode used were not statistically significant. The results of this Professional Brushing Study show that the CrossAction Power toothbrush was as effective as a regular manual toothbrush.

  8. Cross-border innovation cooperation

    DEFF Research Database (Denmark)

    Hjaltadóttir, Rannveig Edda; Makkonen, Teemu; Sørensen, Nils Karl

    2014-01-01

    of cross-border innovation cooperation. Accordingly, geographical proximity to international borders is found to have a significant, positive effect on choosing partners within EU. The multivariate probit model shows that the decision of choosing a domestic innovation partner is independent of the choice......Finding a suitable partner is paramount for the success of innovation cooperation. Thus, this paper sets out to analyse the determinants of cross-border innovation cooperation in Denmark focusing on partner selection. The aim of the article is to investigate determinants of partner selection taking...... the location of the partners into account. In particular, the discussion is tied to the notion of varying knowledge bases firms utilize in their innovation creation processes. Firm level data from the 2010 Community Innovation Survey in Denmark was used to analyse cross-border innovation cooperation patterns...

  9. Greening transportation at the border.

    Science.gov (United States)

    2011-01-01

    On February 2324, 2011, Federal agencies from the United : States, Canada, and Mexico sponsored a workshop in San : Diego, California, to discuss opportunities for improvement : regarding the greening of transportation at the borders.1 : The works...

  10. Intestinal Failure (Short Bowel Syndrome)

    Science.gov (United States)

    Intestinal Failure (Short Bowel Syndrome) What is intestinal failure? Intestinal failure occurs when a significant portion of the small ... intestine does. Who is at risk for intestinal failure? N Babies (usually premature) who have had surgery ...

  11. The influence of tooth brushing time over saliva buffering capacity

    Directory of Open Access Journals (Sweden)

    Sri Mulyanti

    2014-11-01

    Full Text Available Saliva gives a considerable influence against the growth of dental caries as a natural defense against caries. the things very important about saliva are its flow rate and buffering capacity. the decrease in saliva flow rate might cause food retention that furthermore would turn into dental plaques, meanwhile it’s buffering capacity will play a considerable role in maintaining the saliva’s pH and remineralization process of the teeth. One of the mechanisms which are considered to be effective in preventing dental caries is teeth brushing which could change the pH of 5,6 to a normal level. And the right time of teeth brushing will provide an optimal result.The study aims to reveal the influence of teeth brushing time against saliva buffering capacity. The study is an analytic study using a quasi-experimental design. The samples of the study are 20 (twenty students of dentistry in Health Ministry of Bandung which was purposively selected the sample is divided into 3 groups. The first group is treated by brushing their teeth right after eating bread, the second and third group is treated 15 and 30 minutes after eating bread. The hypothesis uses Kruskal Wallis hypothesis continued by Mann Whitney test, strikethrough. The study reveals that the group brushed their teeth right after eating bread shows low category of saliva buffering is that 55% meanwhile those who brushed their teeth 15 and 30 minutes after eating bread exhibits the result as much as 65% and 25 % Thus the last group is included to those who have a medium risk of suffering from dental carries. The statistics of Kruskal Wallis test within the confidence level of 95% shows that there is an influence of teeth brushing time over the saliva buffering capacity with p<0,001. Mann Whitney test shows that the time of teeth brushing within 15 minutes after eating is better than the group who brush their teeth 30 minutes after eating.

  12. Endobiliary brush biopsy: Intra- and interobserver variation in cytological evaluation of brushings from bile duct strictures

    DEFF Research Database (Denmark)

    Adamsen, S; Olsen, M; Jendresen, MB

    2006-01-01

    OBJECTIVE: Obtaining cytological specimens by wire-guided endobiliary brushing at the time of endoscopic retrograde cholangiopancreatography (ERCP) is a convenient way to reach a diagnosis. Sensitivity for malignant disease is generally around 50% and specificity around 100%. The present study...... was designed to assess the reproducibility of the cytological examination. MATERIAL AND METHODS: Samples were obtained from 55 consecutive patients with biliary duct strictures that eventually turned out to be caused by malignant disease in 41 patients (73%). The cytology specimens were evaluated twice...... in different random order with an interval of at least 4 months by two pathologists blinded to the final diagnoses. Suitability for diagnosis (suitable, suboptimal or unsuitable) and cytologic diagnosis (benign, atypical, suspicious for malignancy and malignant cells) were registered. Kappa analysis...

  13. Surface changes of enamel after brushing with charcoal toothpaste

    Science.gov (United States)

    Pertiwi, U. I.; Eriwati, Y. K.; Irawan, B.

    2017-08-01

    The aim of this study was to determine the surface roughness changes of tooth enamel after brushing with charcoal toothpaste. Thirty specimens were brushed using distilled water (the first group), Strong® Formula toothpaste (the second group), and Charcoal® Formula toothpaste for four minutes and 40 seconds (equivalent to one month) and for 14 minutes (equivalent to three months) using a soft fleece toothbrush with a mass of 150 gr. The roughness was measured using a surface roughness tester, and the results were tested with repeated ANOVA test and one-way ANOVA. The value of the surface roughness of tooth enamel was significantly different (p<0.05) after brushing for an equivalent of one month and an equivalent of three months. Using toothpaste containing charcoal can increase the surface roughness of tooth enamel.

  14. Surface Modification of Nonwoven fabrics by Atmospheric Brush Plasma

    Science.gov (United States)

    Oksuz, Lutfi; Uygun, Emre; Bozduman, Ferhat; Yurdabak Karaca, Gozde; Asan, Orkun Nuri; Uygun Oksuz, Aysegul

    2017-10-01

    Polypropylene nonwoven fabrics (PPNF) are used in disposable absorbent articles, such as diapers, feminine care products, wipes. PPNF need to be wettable by water or aqueous-based liquid. Plasma surface treatment/modification has turned out to be a well-accepted method since it offers superior surface property enhancement than other chemical methods. The cold plasma brush can most efficiently use the discharge power as well as the plasma gas for material and surface treatment. The very low power consumption of such an atmospheric argon plasma brush provides many unique advantages in practical application. The purpose of this study was to reveal the effectiveness of non-thermal atmospheric plasma brush in surface wettability and modification of two different nonwoven surfaces.

  15. A New Tribological Test for Candidate Brush Seal Materials Evaluation

    Science.gov (United States)

    Fellenstein, James A.; Dellacorte, Christopher

    1994-01-01

    A new tribological test for candidate brush seal materials evaluation has been developed. The sliding contact between the brush seal wires and their mating counterface journal is simulated by testing a small tuft of wire against the outside diameter of a high speed rotating shaft. The test configuration is similar to a standard block on ring geometry. The new tester provides the capability to measure both the friction and wear of candidate wire and counterface materials under controlled loading conditions in the gram to kilogram range. A wide test condition latitude of speeds (1 to 27 m/s), temperatures (25 to 700 C), and loads (0.5 to 10 N) enables the simulation of many of the important tribological parameters found in turbine engine brush seals. This paper describes the new test rig and specimen configuration and presents initial data for candidate seal materials comparing tuft test results and wear surface morphology to field tested seal components.

  16. Colloidal lithography for fabricating patterned polymer-brush microstructures

    Directory of Open Access Journals (Sweden)

    Tao Chen

    2012-05-01

    Full Text Available We exploit a series of robust, but simple and convenient colloidal lithography (CL approaches, using a microsphere array as a mask or as a guiding template, and combine this with surface-initiated atom-transfer radical polymerization (SI-ATRP to fabricate patterned polymer-brush microstructures. The advantages of the CL technique over other lithographic approaches for the fabrication of patterned polymer brushes are (i that it can be carried out with commercially available colloidal particles at a relatively low cost, (ii that no complex equipment is required to create the patterned templates with micro- and nanoscale features, and (iii that polymer brush features are controlled simply by changing the size or chemical functionality of the microspheres or the substrate.

  17. Polyacrylic acid polymer brushes as substrates for the incorporation of anthraquinone derivatives. Unprecedented application of decorated polymer brushes on organocatalysis

    Science.gov (United States)

    Ruiz-Muelle, Ana Belén; Contreras-Cáceres, Rafael; Oña-Burgos, Pascual; Rodríguez-Dieguez, Antonio; López-Romero, Juan Manuel; Fernández, Ignacio

    2018-01-01

    The synthesis of amino-terminated anthraquinone derivatives and their incorporation onto polymer brushes for the fabrication of silicon-based nanometric functional coatings are described for the first time. The general process involves the covalent grafting of anthraquinone 1 onto two different polymer-brushes by amidation reactions. They are composed by amino- and carboxy-terminated poly(acrylic acid) chains (PAA-NH2- and PAA-COOH, respectively) tethered by one end to an underlying silicon oxide (SiO2) substrate in a polymer brush configuration. A third substrate is fabricated by UV induced hydrosilylation reaction using undecenoic acid as adsorbate on hydrogen-terminated Si(111) surfaces. One- and two-dimensional nuclear magnetic resonance (NMR), FT-IR, MS and X-ray diffraction (XRD) were used to characterize anthraquinone 1. Ellipsometric and X-ray photoelectron spectroscopy (XPS) measurements demonstrated the presence of the polymer brushes on the silicon wafers, and atomic force microscopy (AFM) was used to study its surface morphology. The covalent linkage between anthraquinone and polymer brushes was proven by XPS and confocal fluorescence microscopy. The resulting surfaces were assayed in the heterogenous organocatalytic transformation of (1H)-indole into 3-benzyl indole with moderate yields but with high recyclability.

  18. A Nanosecond Pulsed Plasma Brush for Surface Decontamination

    Science.gov (United States)

    Neuber, Johanna; Malik, Muhammad; Song, Shutong; Jiang, Chunqi

    2015-11-01

    This work optimizes a non-thermal, atmospheric pressure plasma brush for surface decontamination. The generated plasma plumes with a maximum length of 2 cm are arranged in a 5 cm long, brush-like array. The plasma was generated in ambient air with Acinetobacter baumannii. Laminate surfaces inoculated with over-night cultured bacteria were subject to the plasma treatment for varying water concentrations in He, flow rates and discharge voltages. It was found that increasing the water content of the feed gas greatly enhanced the bactericidal effect. Emission spectroscopy was performed to identify the reactive plasma species that contribute to this variation. Additional affiliation: Frank Reidy Research Center for Bioelectrics

  19. Ontogenic Changes of Villus Growth, Lactase Activity, and Intestinal Glucose Transporters in Preterm and Term Born Calves with or without Prolonged Colostrum Feeding.

    Directory of Open Access Journals (Sweden)

    Julia Steinhoff-Wagner

    Full Text Available Oral glucose supply is important for neonatal calves to stabilize postnatal plasma glucose concentration. The objective of this study was to investigate ontogenic development of small intestinal growth, lactase activity, and glucose transporter in calves (n = 7 per group that were born either preterm (PT; delivered by section 9 d before term or at term (T; spontaneous vaginal delivery or spontaneously born and fed colostrum for 4 days (TC. Tissue samples from duodenum and proximal, mid, and distal jejunum were taken to measure villus size and crypt depth, protein concentration of mucosa and brush border membrane vesicles (BBMV, total DNA and RNA concentration of mucosa, mRNA expression and activity of lactase, and mRNA expression of sodium-dependent glucose co-transporter-1 (SGLT1 and facilitative glucose transporter 2 (GLUT2 in mucosal tissue. Additionally, protein expression of SGLT1 in BBMV and GLUT2 in crude mucosal membranes and immunochemical localization of GLUT2 in the enterocytes were determined. Villus height in distal jejunum was lower in TC than in T. Crypt depth in all segments was largest and the villus height/crypt depth ratio in jejunum was smallest in TC calves. Concentration of RNA was highest in duodenal mucosa of TC calves, but neither lactase mRNA and activity nor SGLT1 and GLUT2 mRNA and protein expression differed among groups. Localization of GLUT2 in the apical membrane was greater, whereas in the basolateral membrane was lower in TC than in T and PT calves. Our study indicates maturation processes after birth for mucosal growth and trafficking of GLUT2 from the basolateral to the apical membrane. Minor differences of mucosal growth, lactase activity, and intestinal glucose transporters were seen between PT and T calves, pointing at the importance of postnatal maturation and feeding for mucosal growth and GLUT2 trafficking.

  20. Localizations of Na(+)-D-glucose cotransporters SGLT1 and SGLT2 in human kidney and of SGLT1 in human small intestine, liver, lung, and heart.

    Science.gov (United States)

    Vrhovac, Ivana; Balen Eror, Daniela; Klessen, Dirk; Burger, Christa; Breljak, Davorka; Kraus, Ognjen; Radović, Nikola; Jadrijević, Stipe; Aleksic, Ivan; Walles, Thorsten; Sauvant, Christoph; Sabolić, Ivan; Koepsell, Hermann

    2015-09-01

    Novel affinity-purified antibodies against human SGLT1 (hSGLT1) and SGLT2 (hSGLT2) were used to localize hSGLT2 in human kidney and hSGLT1 in human kidney, small intestine, liver, lung, and heart. The renal locations of both transporters largely resembled those in rats and mice; hSGLT2 and SGLT1 were localized to the brush border membrane (BBM) of proximal tubule S1/S2 and S3 segments, respectively. Different to rodents, the renal expression of hSGLT1 was absent in thick ascending limb of Henle (TALH) and macula densa, and the expression of both hSGLTs was sex-independent. In small intestinal enterocytes, hSGLT1 was localized to the BBM and subapical vesicles. Performing double labeling with glucagon-like peptide 1 (GLP-1) or glucose-dependent insulinotropic peptide (GIP), hSGLT1 was localized to GLP-1-secreting L cells and GIP-secreting K cells as has been shown in mice. In liver, hSGLT1 was localized to biliary duct cells as has been shown in rats. In lung, hSGLT1 was localized to alveolar epithelial type 2 cells and to bronchiolar Clara cells. Expression of hSGLT1 in Clara cells was verified by double labeling with the Clara cell secretory protein CC10. Double labeling of human heart with aquaporin 1 immunolocalized the hSGLT1 protein in heart capillaries rather than in previously assumed myocyte sarcolemma. The newly identified locations of hSGLT1 implicate several extra renal functions of this transporter, such as fluid absorption in the lung, energy supply to Clara cells, regulation of enteroendocrine cells secretion, and release of glucose from heart capillaries. These functions may be blocked by reversible SGLT1 inhibitors which are under development.

  1. Transport of the photodynamic therapy agent 5-aminolevulinic acid by distinct H+-coupled nutrient carriers coexpressed in the small intestine.

    Science.gov (United States)

    Anderson, Catriona M H; Jevons, Mark; Thangaraju, Muthusamy; Edwards, Noel; Conlon, Nichola J; Woods, Steven; Ganapathy, Vadivel; Thwaites, David T

    2010-01-01

    5-Aminolevulinic acid (ALA) is a prodrug used in photodynamic therapy, fluorescent diagnosis, and fluorescent-guided resection because it leads to accumulation of the photosensitizer protoporphyrin IX (PpIX) in tumor tissues. ALA has good oral bioavailability, but high oral doses are required to obtain selective PpIX accumulation in colonic tumors because accumulation is also observed in normal gut mucosa. Structural similarities between ALA and GABA led us to test the hypothesis that the H(+)-coupled amino acid transporter PAT1 (SLC36A1) will contribute to luminal ALA uptake. Radiolabel uptake and electrophysiological measurements identified PAT1-mediated H(+)-coupled ALA symport after heterologous expression in Xenopus oocytes. The selectivity of the nontransported inhibitors 5-hydroxytryptophan and 4-aminomethylbenzoic acid for, respectively, PAT1 and the H(+)-coupled di/tripeptide transporter PepT1 (SLC15A1) were examined. 5-Hydroxytryptophan selectively inhibited PAT1-mediated amino acid uptake across the brush-border membrane of the human intestinal (Caco-2) epithelium whereas 4-aminomethylbenzoic acid selectively inhibited PepT1-mediated dipeptide uptake. The inhibitory effects of 5-hydroxytryptophan and 4-aminomethylbenzoic acid were additive, demonstrating that both PAT1 and PepT1 contribute to intestinal transport of ALA. This is the first demonstration of overlap in substrate specificity between these distinct transporters for amino acids and dipeptides. PAT1 and PepT1 expression was monitored by reverse transcriptase-polymerase chain reaction using paired samples of normal and cancer tissue from human colon. mRNA for both transporters was detected. PepT1 mRNA was increased 2.3-fold in cancer tissues. Thus, increased PepT1 expression in colonic cancer could contribute to the increased PpIX accumulation observed. Selective inhibition of PAT1 could enhance PpIX loading in tumor tissue relative to that in normal tissue.

  2. Cross-border innovation cooperation

    DEFF Research Database (Denmark)

    Hjaltadóttir, Rannveig Edda; Makkonen, Teemu; Sørensen, Nils Karl

    2017-01-01

    of innovativeness increase the likelihood of cross-border innovation cooperation. Accordingly, geographical proximity to international borders is found to have a significant, positive effect on selecting partners within the European Union. The multivariate probit model shows that the decision of choosing a domestic......Finding a suitable partner is paramount for the success of innovation cooperation. Thus, this paper sets out to analyse the determinants of cross-border innovation cooperation in Denmark by focusing on partner selection. The aim of the article is to investigate determinants of partner selection...... cooperation patterns of Danish firms focusing on their choices of foreign innovation partners. The results indicate that firm size and research and development (R&D) intensity have a positive effect on firm’s propensity to cooperate on innovation and that having R&D activities abroad as well as high level...

  3. Thermal design and development of actively cooled brushes for compact homopolar generators

    Science.gov (United States)

    Makel, D. B.

    1986-11-01

    The thermal and hydraulic design of actively cooled current transfer brushes for compact homopolar generators (HPG) is described. The development of high-energy-density HPG's at the Center for Electromechanics at the University of Texas at Austin requires brushgear capable of handling high current densities and large thermal loads. Platelet technology has been applied in the design of actively cooled brushes with coolant injection directly from the brush contact face into the brush-rotor interface. Coolant channels a few thousandths of an inch in diameter have been designed in brushes constructed of photoetched platelets of copper (0.020 to 0.005 in. thick) and then bonded to form the cooled brush. Platelet construction of brushes also permits the incorporation of internal instrumentation for temperature measurement. The brushes have been designed to provide data on the effects of rotor speed, current level, coolant flow rate, and coolant injection pattern.

  4. Why Iranian adolescents do not brush their teeth: a qualitative study.

    Science.gov (United States)

    Pakpour, A H; Hidarnia, A; Hajizadeh, E; Kumar, S; Fridlund, B

    2012-05-01

    To explore and describe attitudes towards tooth-brushing among Iranian adolescents. A series of focus-group sessions were held with 37 Iranian adolescents in schools. The groups comprised five to eight adolescents. All focus-group discussions were tape-recorded and then transcribed verbatim. All transcripts, codes and categories were read several times to extract a theme. Data were analysed using a qualitative content analysis approach. Four major categories emerged from the analysis: brushing teeth is a necessary evil, parental influence on not brushing teeth, brushing teeth is insignificant, and brushing teeth is a health hazard. The theme identified in the latent content described that tooth-brushing is not part of the adolescents' activities of daily living. Health educators should stress on the engagement of parents, awareness of the adolescents on brushing techniques and causes of toothache, and address any misconceptions regarding tooth-brushing. © 2011 John Wiley & Sons A/S.

  5. The Effect of the Border on Chinese Direct Investments : Evidence from Russian Border Regions

    OpenAIRE

    Novopashina, Alina

    2013-01-01

    This paper describes the effects of the border on Chinese direct investments to Russian border regions. The findings of this paper show that Chinese direct investments to Russia gravitated to industries in the border regions exporting their goods to China and to the production of non-tradable goods in non-border regions. The net Chinese foreign direct investments (FDI) inflow to Russian border regions is very small but the development of border trade led to informal investments be...

  6. Stimuli-Responsive Polyelectrolyte Brushes As a Matrix for the Attachment of Gold Nanoparticles: The Effect of Brush Thickness on Particle Distribution

    Directory of Open Access Journals (Sweden)

    Stephanie Christau

    2014-06-01

    Full Text Available The effect of brush thickness on the loading of gold nanoparticles (AuNPs within stimuli-responsive poly-(N,N-(dimethylamino ethyl methacrylate (PDMAEMA polyelectrolyte brushes is reported. Atom transfer radical polymerization (ATRP was used to grow polymer brushes via a “grafting from” approach. The brush thickness was tuned by varying the polymerization time. Using a new type of sealed reactor, thick brushes were synthesized. A systematic study was performed by varying a single parameter (brush thickness, while keeping all other parameters constant. AuNPs of 13 nm in diameter were attached by incubation. X-ray reflectivity, electron scanning microscopy and ellipsometry were used to study the particle loading, particle distribution and interpenetration of the particles within the brush matrix. A model for the structure of the brush/particle hybrids was derived. The particle number densities of attached AuNPs depend on the brush thickness, as do the optical properties of the hybrids. An increasing particle number density was found for increasing brush thickness, due to an increased surface roughness.

  7. A new insight into the counterion distribution of charged polymer brushes

    Science.gov (United States)

    Chu, Xiao; Liu, Guangming; Zhao, Jiang

    2014-03-01

    Counterions distribution of a number of polyeletrolyte brushes are investigated using a combination of methods as QCM-D, ellipsomety and single molecule fluorescence microscopy. The experiemtnal evidence show that, as the salt level increases, counterions penetrate into the brushes, bringing about enhanced swelling and mechanical response of the brushes. The results have privided a new picture about counterion distribution of charged polymer brushes. Supported by National Natural Science Foundatrion of China.

  8. Contaminated tooth brushes-potential threat to oral and general health

    OpenAIRE

    Rashmi Naik; B R Ahmed Mujib; Neethu Telagi; B S Anil; B R Spoorthi

    2015-01-01

    Background: Tooth brushing is most common method of maintaining oral hygiene. In removing plaque and other soft debris from the teeth, tooth brushes become contaminated with bacteria, blood, saliva and oral debris. These contaminated tooth brushes can be a source of infection. Aims and objectives: The aim of the present study was to evaluate the presence of microorganisms in the tooth brushes and to investigate the effect of disinfectants such as chlorhexidine gluconate, sodium hypochlorite a...

  9. Some metallographic results for brush bristles and brush segments of a shroud ring brush seal tested in a T-700 engine

    Science.gov (United States)

    Hendricks, Robert C.; Griffin, Thomas A.; Bobula, George A.; Bill, Robert C.; Hull, David R.; Csavina, Kristine R.

    1994-07-01

    Post-test investigation of a T-700 engine brush seal found regions void of bristles ('yanked out'), regions of bent-over bristles near the inlet, some 'snapped' bristles near the fence, and a more uniform smeared bristle interface between the first and last axial rows of bristles. Several bristles and four brush segments were cut from the brush seal, wax mounted, polished, and analyzed. Metallographic analysis of the bristle near the rub tip showed tungsten-rich phases uniformly distributed throughout the bristle, no apparent change within 1 mu m of the interface, and possibly a small amount of titanium, which would represent a transfer from the rotor. Analysis of the bristle wear face showed nonuniform tungsten, which is indicative of material resolidification. The cut end contained oxides and internal fractures; the worn end was covered with oxide scale. Material losses due to wear and elastoplastic deformation within the shear zone and third-body lubrication effects in the contact zone are discussed.

  10. Up-regulation of intestinal vascular endothelial growth factor by Afa/Dr diffusely adhering Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Gaëlle Cane

    Full Text Available BACKGROUND: Angiogenesis has been recently described as a novel component of inflammatory bowel disease pathogenesis. The level of vascular endothelial growth factor (VEGF has been found increased in Crohn's disease and ulcerative colitis mucosa. To question whether a pro-inflammatory Escherichia coli could regulate the expression of VEGF in human intestinal epithelial cells, we examine the response of cultured human colonic T84 cells to infection by E. coli strain C1845 that belongs to the typical Afa/Dr diffusely adhering E. coli family (Afa/Dr DAEC. METHODOLOGY: VEGF mRNA expression was examined by Northern blotting and q-PCR. VEGF protein levels were assayed by ELISA and its bioactivity was analysed in endothelial cells. The bacterial factor involved in VEGF induction was identified using recombinant E. coli expressing Dr adhesin, purified Dr adhesin and lipopolysaccharide. The signaling pathway activated for the up-regulation of VEGF was identified using a blocking monoclonal anti-DAF antibody, Western blot analysis and specific pharmacological inhibitors. PRINCIPAL FINDINGS: C1845 bacteria induce the production of VEGF protein which is bioactive. VEGF is induced by adhering C1845 in both a time- and bacteria concentration-dependent manner. This phenomenon is not cell line dependent since we reproduced this observation in intestinal LS174, Caco2/TC7 and INT407 cells. Up-regulation of VEGF production requires: (1 the interaction of the bacterial F1845 adhesin with the brush border-associated decay accelerating factor (DAF, CD55 acting as a bacterial receptor, and (2 the activation of a Src protein kinase upstream of the activation of the Erk and Akt signaling pathways. CONCLUSIONS: Results demonstrate that a Afa/Dr DAEC strain induces an adhesin-dependent activation of DAF signaling that leads to the up-regulation of bioactive VEGF in cultured human intestinal cells. Thus, these results suggest a link between an entero-adherent, pro

  11. Enhanced stability of low fouling zwitterionic polymer brushes in seawater with diblock architecture

    NARCIS (Netherlands)

    Quintana, R.; Gosa, M.; Janczewski, D.; Kutnyanszky, E.; Vancso, Gyula J.

    2013-01-01

    The successful implementation of zwitterionic polymeric brushes as antifouling materials for marine applications is conditioned by the stability of the polymer chain and the brush-anchoring segment in seawater. Here we demonstrate that robust, antifouling, hydrophilic polysulfobetaine-based brushes

  12. A PET activation study of brush-evoked allodynia in patients with nerve injury pain

    DEFF Research Database (Denmark)

    Witting, Nanna; Kupers, Ron; Svensson, Peter

    2006-01-01

    during allodynic brushing. No thalamic activation was observed during allodynic or control brushing. Although no anterior cingulate cortex (ACC) activation could be demonstrated in the group analysis, single subject analysis revealed that four patients activated this region during brush-evoked allodynia...

  13. 46 CFR 108.187 - Ventilation for brush type electric motors in classified spaces.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ventilation for brush type electric motors in classified... Ventilation for brush type electric motors in classified spaces. Ventilation for brush type electric motors in... the motors may cause unsafe conditions. Accommodation Spaces ...

  14. Synthesis and characterization of metal oxide nanorod brushes

    Indian Academy of Sciences (India)

    WINTEC

    ducing chromium ions during the synthesis of alumina rods. Keywords. Metal oxide nanorods; nanorod brushes; alumina nanorods; MoO3 nanorods; ZnO nanorods; ruby nanorods. 1. Introduction. Synthesis of one-dimensional metal oxide nanostructures is getting enormous attention in recent years due to their potential ...

  15. Polymer brush-functionalized chitosan hydrogels as antifouling implant coatings

    Czech Academy of Sciences Publication Activity Database

    Buzzacchera, I.; Vorobii, M.; Kostina, N. Yu.; de los Santos Pereira, Andres; Riedel, Tomáš; Bruns, M.; Ogieglo, W.; Möller, M.; Wilson, C. J.; Rodriguez-Emmenegger, C.

    2017-01-01

    Roč. 18, č. 6 (2017), s. 1983-1992 ISSN 1525-7797 R&D Projects: GA ČR(CZ) GBP205/12/G118 Institutional support: RVO:61389013 Keywords : chitosan * hemocompatible * polymer brushes Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 5.246, year: 2016

  16. Clickable antifouling polymer brushes for polymer pen lithography

    Czech Academy of Sciences Publication Activity Database

    Bog, U.; de los Santos Pereira, Andres; Mueller, S. L.; Havenridge, S.; Parrillo, Viviana; Bruns, M.; Holmes, A. E.; Rodriguez-Emmenegger, C.; Fuchs, H.; Hirtz, M.

    2017-01-01

    Roč. 9, č. 13 (2017), s. 12109-12117 ISSN 1944-8244 R&D Projects: GA ČR(CZ) GJ15-09368Y Institutional support: RVO:61389013 Keywords : antifouling * biofunctional interfaces * polymer brushes Subject RIV: CD - Macromolecular Chemistry OBOR OECD: Polymer science Impact factor: 7.504, year: 2016

  17. Modeling the structure of a polydisperse polymer brush

    NARCIS (Netherlands)

    Vos, de W.M.; Leermakers, F.A.M.

    2009-01-01

    Numerical self-consistent field theory is used to study the structural characteristics of a polydisperse polymer brush. We consider the relevant case of a Schulz–Zimm distribution and find that even a small degree of polydispersity completely destroys the parabolic density profile. The first moment

  18. Bacterial adhesion and growth on a polymer brush-coating

    NARCIS (Netherlands)

    Nejadnik, M.R.; Mei, van der H.C.; Norde, W.; Busscher, H.J.

    2008-01-01

    Biomaterials-related infections pose serious problems in implant surgery, despite the development of non-adhesive coatings. Non-adhesive coatings, like polymer brush-coatings, have so far only been investigated with respect to preventing initial bacterial adhesion, but never with respect to effects

  19. Multifocal Rhizopus microsporus lung infection following brush clearing

    Directory of Open Access Journals (Sweden)

    Artsiom V. Tsyrkunou

    2014-10-01

    Full Text Available We report a case of pulmonary Rhizopus microsporus infection in a patient with untreated diabetes following brush clearing. The patient was successfully treated with a combined medical and surgical approach with complete resolution of the lung lesions and remains asymptomatic at 11-month follow-up.

  20. Suppressing Pseudomonas aeruginosa adhesion via non-fouling polymer brushes

    Czech Academy of Sciences Publication Activity Database

    Rodriguez-Emmenegger, Cesar; Decker, A.; Surman, František; Preuss, C. M.; Sedláková, Zdeňka; Zydziak, N.; Barner-Kowollik, C.; Schwartz, T.; Barner, L.

    2014-01-01

    Roč. 4, č. 110 (2014), s. 64781-64790 ISSN 2046-2069 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0109; GA ČR GAP106/12/1451 Institutional support: RVO:61389013 Keywords : polymer brushes * tissue engineering * biology Subject RIV: CD - Macromolecular Chemistry Impact factor: 3.840, year: 2014

  1. Radiocesium movement in a gray rabbit brush community

    International Nuclear Information System (INIS)

    Klepper, B.; Rogers, L.E.; Hedlund, J.D.; Schreckhise, R.G.; Price, K.R.

    1978-01-01

    Gray rabbit brush, Chrysothamnus nauseosus (Compositae), is the dominant shrub on disturbed land surfaces on much of the Energy Research and Development Administration's Hanford Reservation in south-central Washington State. A stand of rabbit brush growing on an inactive liquid-waste-disposal crib was studied. Thirty percent of the shrubs showed low but detectable radiation levels in a field survey. The primary radionuclide was 137 Cs. The source of 137 Cs in shrubs was the gravel drain field in the crib, at least 2.4 m below the surface, which was the approximate maximum depth of penetration of rabbit brush taproots. Cesium-137 was observed in roots of certain rabbit brush plants, in the upper 1 cm of soil, and in litter beneath contaminated plants but was not detectable in soil samples taken at depths of 15, 50, 100, and 150 cm. Invertebrates associated with a contaminated shrub showed higher concentrations of 137 Cs than did wider-ranging species. Two of seven pocket mice trapped on the crib contaminated detectable amounts of 137 Cs

  2. Superhydrophilic Polyelectrolyte Brush Layers with Imparted Anti-Icing Properties

    DEFF Research Database (Denmark)

    Chernyy, Sergey; Järn, Mikael; Shimizu, Kyoko

    2014-01-01

    by polymerization via the SI-ATRP route. The cationic [2-(methacryloyloxy)ethyl]trimethylammonium chloride] and the anionic [poly(3-sulfopropyl methacrylate), poly(sodium methacrylate)] polyelectrolyte brushes were further exchanged with H(+), Li(+), Na(+), K(+), Ag(+), Ca(2+), La(3+), C16N(+), F(-), Cl(-), BF4...

  3. Tooth brushing, tongue cleaning and snacking behaviour of dental ...

    African Journals Online (AJOL)

    Objective: To determine the tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students. Methods: A descriptive cross-sectional study of students of Federal School of Dental Therapy and Technology Enugu, Nigeria. Self-administered questionnaire was used to obtain information on ...

  4. Crossing borders via mental bridges

    DEFF Research Database (Denmark)

    Keil, Dirk

    administration, and in specific on the attempt to initiate and promote cross-border regional integration via the building of mental bridges between Danish and German parts of the Femern Belt Region. Here one of the first projects aiming primarily at building mental bridges in the Femern Belt Region...

  5. Border Crossing/Entry Data - Boarder Crossing

    Data.gov (United States)

    Department of Transportation — Border Crossing/Entry Data provides summary statistics for incoming crossings at the U.S.-Canadian and the U.S.-Mexican border at the port level. Data are available...

  6. Structure of the animal vitreoretinal border region

    DEFF Research Database (Denmark)

    Heegaard, Steffen

    1994-01-01

    Øjenpatologi, vitreoretinal border region, inner limiting membrane of the retina, animals, ultrastructure, comparative anatomy......Øjenpatologi, vitreoretinal border region, inner limiting membrane of the retina, animals, ultrastructure, comparative anatomy...

  7. Buried, Covalently Attached RGD Peptide Motifs in Poly(methacryllic) Brush Layers; The Effect of Brush Structure on Cell Adhesion

    NARCIS (Netherlands)

    Navarro, Melba; Benetti, Edmondo Maria; Zapotoczny, S.J.; Planell, Josep A.; Vancso, Gyula J.

    2008-01-01

    Iniferter-mediated surface-initiated photopolymerization was used to graft poly(methacrylic acid) (PMAA) brush layers obtained from surface-attached iniferters in self-assembled monolayers to a gold surface. The tethered chains were subsequently functionalized with the cell-adhesive

  8. Intestinal microbiome landscaping

    NARCIS (Netherlands)

    Shetty, Sudarshan A.; Hugenholtz, Floor; Lahti, Leo; Smidt, Hauke; Vos, de Willem M.

    2017-01-01

    High individuality, large complexity and limited understanding of the mechanisms underlying human intestinal microbiome function remain the major challenges for designing beneficial modulation strategies. Exemplified by the analysis of intestinal bacteria in a thousand Western adults, we discuss

  9. Briefing : the Eritrean-Ethiopian border dispute

    NARCIS (Netherlands)

    Abbink, G.J.

    1998-01-01

    On 6 May 1998, a violent conflict erupted in the Ethiopian-Eritrean border area. This article contends that this border crisis is neither unexpected nor the result of a real border dispute. Rather, it is due to three factors: the particular history and relationship of the two insurgent movements

  10. Cross-border merger and domestic welfare

    OpenAIRE

    Arijit Mukherjee

    2006-01-01

    We consider the welfare effect of cross-border merger in presence of international R&D competition. Cross-border merger increases domestic welfare if the bargaining power of the foreign firm and the slope of the marginal cost of R&D are sufficiently low. Otherwise, domestic welfare is lower under cross-border merger.

  11. Cross-Border Exposures and Financial Contagion

    NARCIS (Netherlands)

    Degryse, H.A.; Elahi, M.A.; Penas, M.F.

    2009-01-01

    Integrated financial markets provide opportunities for expansion and improved risk sharing, but also pose threats of contagion risk through cross-border exposures. This paper examines cross-border contagion risk over the period 1999-2006. To that purpose we use aggregate cross-border exposures of

  12. Recent trends in cross-border banking

    NARCIS (Netherlands)

    De Haas, Ralph; van Horen, Neeltje; Beck, Thorsten; Casu, Barbara

    2017-01-01

    This chapter identifies a number of recent trends in European cross-border banking. The authors first distinguish between two main modes of international banking: cross-border versus multinational banking. Cross-border banking occurs when a bank in country A lends directly to a borrower in country

  13. European Banks Straddling Borders: Risky or Rewarding?

    NARCIS (Netherlands)

    P. Duijm (Patty); D. Schoenmaker (Dirk)

    2017-01-01

    textabstractTheory suggests that cross-border banking is beneficial as long as there is a non-perfect correlation across country-specific risks. Using a unique hand-collected dataset with cross-border loans for the 61 largest European banks, we find that cross-border banking in general decreases

  14. The impact of Border policy effect on cross-border ethnic areas

    Science.gov (United States)

    Bie, Q. L.; Zhou, S. Y.; Li, C. S.

    2013-11-01

    Boundary effect analysis is related to border policy making in the cross-border ethnic area. The border effect literatures show that geographic boundaries have obvious impacts on economic, social and cultural relations in both sides of a nation border. Particularly in cross-border ethnic areas, each ethnic group has strong internal spatial structure relevance, and the boundary effect is more obvious. However, most of China's border areas are cross-border ethnic areas, each of border issues is unique. Under this perspective, we analyze the border effects of various boundaries can provide basis for formulating border management policies. For small scale of cross-border ethnic minority areas, how to formulate the boundary management policy is a good question to explore. This paper is demonstrated by a study of the impact of border management policies in Dehong Dai and Jingpo Autonomous Prefecture in Yunnan Province at the border area to Burma. The comparative method is used to analysis the border management policies in past 50 decades for the border area of Yunnan Province .This research aims to define trends within border policy and its influences to national security. This paper also examines Wendy Brown's liberal theory of border management policy. We found that it is not suitable for Sino-Burma border area. The conclusion is that the changes or instability of international economic and political situation has more influence to this cross-border ethnic area, and only innovative policy will be effective in cross-border ethnic area. So the border management policies should reflect the change of international context.

  15. Old Borders and New Bordering Capabilities: Cities as Frontier Zones

    Directory of Open Access Journals (Sweden)

    Saskia Sassen

    2015-12-01

    Full Text Available The global city is a new frontier zone. Deregulation, privatization, and new fiscal and monetary policies create the formal instruments to construct their equivalent of the old military “fort”. The city is also a strategic frontier zone for those who lack power, and allows the making of informal politics. At the same time the border is a mix of regimes, marked by protections and opportunities for corporations and high-level professionals, and implies confinement, capture and detention for migrants. The essay discusses the transformation of the city in a frontier zone and analyses the separation between the capabilities entailed by territoriality and the geographic territory tout court. The analysis focuses on the effects of neoliberal policies that, far from making this a borderless world, have actually multiplied the bordered spaces that allow firms and markets to move across conventional borders. Cities are therefore one of the key sites where new neoliberal norms are made and where new identities emerge.

  16. Small Intestine Cancer Treatment

    Science.gov (United States)

    ... all of an organ that contains cancer. The resection may include the small intestine and nearby organs (if the cancer has spread). The doctor may remove the section of the small intestine that contains cancer and perform an anastomosis (joining the cut ends of the intestine together). ...

  17. Quantitative evaluation of toothbrush and arm-joint motion during tooth brushing.

    Science.gov (United States)

    Inada, Emi; Saitoh, Issei; Yu, Yong; Tomiyama, Daisuke; Murakami, Daisuke; Takemoto, Yoshihiko; Morizono, Ken; Iwasaki, Tomonori; Iwase, Yoko; Yamasaki, Youichi

    2015-07-01

    It is very difficult for dental professionals to objectively assess tooth brushing skill of patients, because an obvious index to assess the brushing motion of patients has not been established. The purpose of this study was to quantitatively evaluate toothbrush and arm-joint motion during tooth brushing. Tooth brushing motion, performed by dental hygienists for 15 s, was captured using a motion-capture system that continuously calculates the three-dimensional coordinates of object's motion relative to the floor. The dental hygienists performed the tooth brushing on the buccal and palatal sides of their right and left upper molars. The frequencies and power spectra of toothbrush motion and joint angles of the shoulder, elbow, and wrist were calculated and analyzed statistically. The frequency of toothbrush motion was higher on the left side (both buccal and palatal areas) than on the right side. There were no significant differences among joint angle frequencies within each brushing area. The inter- and intra-individual variations of the power spectrum of the elbow flexion angle when brushing were smaller than for any of the other angles. This study quantitatively confirmed that dental hygienists have individual distinctive rhythms during tooth brushing. All arm joints moved synchronously during brushing, and tooth brushing motion was controlled by coordinated movement of the joints. The elbow generated an individual's frequency through a stabilizing movement. The shoulder and wrist control the hand motion, and the elbow generates the cyclic rhythm during tooth brushing.

  18. Evaluation of multi-brush anode systems in microbial fuel cells

    KAUST Repository

    Lanas, Vanessa

    2013-11-01

    The packing density of anodes in microbial fuel cells (MFCs) was examined here using four different graphite fiber brush anode configurations. The impact of anodes on performance was studied in terms of carbon fiber length (brush diameter), the number of brushes connected in parallel, and the wire current collector gage. MFCs with different numbers of brushes (one, three or six) set perpendicular to the cathode all produced similar power densities (1200±40mW/m2) and coulombic efficiencies (60%±5%). Reducing the number of brushes by either disconnecting or removing them reduced power, demonstrating the importance of anode projected area covering the cathode, and therefore the need to match electrode projected areas to maintain high performance. Multi-brush reactors had the same COD removal as single-brush systems (90%). The use of smaller Ti wire gages did not affect power generation, which will enable the use of less metal, reducing material costs. © 2013 Elsevier Ltd.

  19. Impact of self-tongue brushing on taste perception in Thai older adults: A pilot study.

    Science.gov (United States)

    Madiloggovit, Jirakate; Chotechuang, Nattida; Trachootham, Dunyaporn

    2016-01-01

    Oral hygiene influences taste, affecting appetite and nutrition in older adults. However, the impact of self-administered tongue brushing on their taste perceptions was unclear. This pilot study (N = 44) was aimed to observe the changes in taste thresholds using Filter Paper Disc after tongue brushing in Thai older adults. Based on the results, continuous tongue brushing for 3 months reduced tongue coat (p tongue, while sour and bitter thresholds were reduced only in posterior tongue. No changes in umami (savory) were observed. Daily brushing was more effective than weekly brushing in improving the sweet and bitter tastes. The data suggested that tongue brushing could improve perception of multiple tastes and daily tongue brushing was recommended as routine personal care for older adults. This study supports further investigation in a randomized-controlled setting. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Tooth brushing frequency and risk of new carious lesions.

    Science.gov (United States)

    Holmes, Richard D

    2016-12-01

    Data sourcesMedline, Embase, CINHAL and the Cochrane databases.Study selectionTwo reviewers selected studies, and case-control, prospective cohort, retrospective cohort and experimental trials evaluating the effect of toothbrushing frequency on the incidence or increment of new carious lesions were considered.Data extraction and synthesisTwo reviewers undertook data abstraction independently using pre-piloted forms. Study quality was assessed using a quality assessment tool for quantitative studies developed by the Effective Public Health Practice Project (EPHPP). Meta-analysis of caries outcomes was carried out using RefMan and meta-regressions undertaken to assess the influence of sample size, follow-up period, caries diagnosis level and study methodological quality.ResultsThirty-three studies were included of which 13 were considered to be methodologically strong, 14 moderate and six weak. Twenty-five studies contributed to the quantitative analysis. Compared with frequent brushers, self-reported infrequent brushers demonstrated a higher incidence of carious lesions, OR=1.50 (95%CI: 1.34 -1.69). The odds of having carious lesions differed little when subgroup analysis was conducted to compare the incidence between ≥2 times/d vs Brushing brushing, standardised mean difference [SMD] =0.34; (95%CI; 0.18 - 0.49). Overall, infrequent brushing was associated with an increment of carious lesions, SMD= 0.28; (95%CI; 0.13 - 0.44). Meta-analysis conducted with the type of dentition as subgroups found the effect of infrequent brushing on incidence and increment of carious lesions was higher in deciduous, OR=1.75; (95%CI; 1.49 - 2.06) than permanent dentition OR=1.39; (95% CI: 1.29 -1.49). Meta-regression indicated that none of the included variables influenced the effect estimate.ConclusionsIndividuals who state that they brush their teeth infrequently are at greater risk for the incidence or increment of new carious lesions than those brushing more frequently. The

  1. Internal Border Controls in the European Union

    DEFF Research Database (Denmark)

    Jørgensen, Carsten Willemoes; Sørensen, Karsten Engsig

    2012-01-01

    Recent events, involving inter alia France and Denmark, have stimulated renewed interest in the introduction of different forms of border controls at the internal borders within the European Union. These border control measures are aimed at checking either persons or goods or both. Against...... the background of these events, this article analyses the existing rules regulating controls of persons and goods, and explores how these rules may or may not stand in the way of introducing border controls at the European Union’s internal borders. These events have resulted in a call for reforms of the current...

  2. Cross-border reprogenetic services.

    Science.gov (United States)

    Couture, V; Drouin, R; Tan, S-L; Moutquin, J-M; Bouffard, C

    2015-01-01

    The purpose of this review is to synthesize the current knowledge on the international movement of patients and biopsied embryo cells for pre-implantation genetic diagnosis and its different applications. Thus far, few attempts have been made to identify the specific nature of this phenomenon called 'cross-border reprogenetic services'. There is scattered evidence, both empirical and speculative, suggesting that these services raise major issues in terms of service provision, risks for patients and the children-to-come, the legal liabilities of physicians, as well as social justice. To compile this evidence, this review uses the narrative overview protocol combined with thematic analysis. Five major themes have emerged from the literature at the conjunction of cross-border treatments and reprogenetics: 'scope', 'scale', 'motivations', 'concerns', and 'governance'. Similar themes have already been observed in the case of other medical tourism activities, but this review highlights their singularity with reprogenetic services. It emphasizes the diagnostic and autologous feature of reprogenetics, the constant risk of misdiagnosis, the restriction on certain tests for medically controversial conditions, and the uncertain accessibility of genetic counseling in cross-border settings. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Border malaria in Yunnan, China.

    Science.gov (United States)

    Xu, J; Liu, H

    1997-09-01

    Yunnan Province, due its international borders with Myanmar, Vietnam and Lao PDR has a large number of imported cases of malaria, including a high proportion of Plasmodium falciparum, as a result of the mobility of the population. This movement is due to workers coming from other provinces where there is no malaria to work in the productive tropical lowlands. Chinese nationals who have gone to work in neighboring countries, border trade and refugees from Myanmar. Much of Yunnan is peopled by ethnic minorities living in remote mountainous and forested areas which are difficult to reach. However, surveillance has been strengthened by training 3,900 primary health care workers and combining the search for visiting foreigners, returning Chinese and people from other provinces with public security, customs formalities and employers. Any visitor detected by these services is obliged to have a blood slide taken. This has resulted in an earlier and more complete detection of malaria cases, reducing incidence from 19.19 to 12.12/10,000 in the border area over the last 10 years. This is despite a considerable increase in population movement and the threat of drug resistant malaria.

  4. A randomized clinical trial evaluating gingivitis and plaque reduction of an oscillating-rotating power brush with a new brush head with angled bristles versus a marketed sonic brush with self-adjusting technology.

    Science.gov (United States)

    Klukowska, Malgorzata; Grender, Julie M; Conde, Erinn; Ccahuana-Vasquez, Renzo Alberto; Ram Goyal, C

    2014-08-01

    To compare the efficacy of an oscillating-rotating power toothbrush with a novel brush head incorporating angled CrissCross bristles (Oral-B Pro 7000 SmartSeries and Oral-B CrossAction brush head) versus a marketed sonic toothbrush (Colgate ProClinical A1500 with the Triple Clean brush head) in the reduction of gingivitis and plaque over a 6-week period. This was a single center, randomized, open label, examiner-blind, 2-treatment, parallel group study. Study participants who met the entrance criteria were enrolled in the study and randomly assigned to one of the two toothbrush groups. Study participants brushed with their assigned toothbrush and a marketed fluoride dentifrice for 2 minutes twice daily at home for 6 weeks. Gingivitis and plaque were evaluated at baseline and Week 6. Gingivitis was assessed using the Modified Gingival Index (MGI) and Gingival Bleeding Index (GBI) and plaque was assessed using the Rustogi Modified Navy Plaque Index (RMNPI). Data was analyzed using the ANCOVA with baseline as the covariate. In total, 130 study participants were randomized to treatment resulting in 64 study participants per group completing the study. Both brushes produced statistically significant (P gingivitis and plaque measures relative to baseline. The oscillating-rotating,brush with the novel brush head demonstrated statistically significantly (P gingivitis measures, as well as whole mouth and interproximal plaque measures, compared to the sonic toothbrush. The benefit for the oscillating- rotating brush over the sonic brush was 21.3% for gingivitis, 35.7% for gingival bleeding, 34.7% for number of bleeding sites, 17.4% for whole mouth plaque, and 21.2% for interproximal plaque. There were no adverse events reported or observed for either brush.

  5. Cholera toxin entry into pig enterocytes occurs via a lipid raft- and clathrin-dependent mechanism

    DEFF Research Database (Denmark)

    Hansen, Gert H; Dalskov, Stine-Mathilde; Rasmussen, Christina Rehné

    2005-01-01

    The small intestinal brush border is composed of lipid raft microdomains, but little is known about their role in the mechanism whereby cholera toxin gains entry into the enterocyte. The present work characterized the binding of cholera toxin B subunit (CTB) to the brush border and its...

  6. Cross-border regional innovation systems

    DEFF Research Database (Denmark)

    Makkonen, Teemu; Rohde, Stephan

    2016-01-01

    The concept of cross-border regional innovation systems (CBRIS) surfaced in the literature on economic geography through discourses that highlighted the need of broadening innovation systems to cross-border contexts. Since these early discussions, the theoretical backgrounds of CBRIS have been el...... of understanding how suggested policy measures based on CBRIS reasoning have been implemented in border regions, and their effectiveness in promoting cross-border integration.......The concept of cross-border regional innovation systems (CBRIS) surfaced in the literature on economic geography through discourses that highlighted the need of broadening innovation systems to cross-border contexts. Since these early discussions, the theoretical backgrounds of CBRIS have been...... elaborated through notions of geographical scale, proximity and related variety in a range of conceptual papers proposing CBRIS as a comprehensive framework for analysing regional cross-border integration. However, the empirical literature on CBRIS has failed to keep up with the advances in conceptualisation...

  7. Internal architecture of zwitterionic polymer brushes regulates nonfouling properties.

    Science.gov (United States)

    Huang, Chun-Jen; Li, Yuting; Krause, Jordan B; Brault, Norman D; Jiang, Shaoyi

    2012-06-14

    In this work, we study how film thickness and chain packing density affect the protein-resistant properties of polymer brushes in complex media. Polymer brushes based on dual-functional poly(carboxybetaine acrylamide) (pCB) were prepared via surface-initiated photoiniferter-mediated polymerization. By adjusting UV radiation time and solvent polarity, pCB films with different thicknesses can be achieved and characterized using an ellipsometer. The packing density of pCB polymer chains is directly related to the swelling ratio of swollen to collapsed film thicknesses. Results showed that the dry film thickness alone, used often in the literature, is not sufficient to correlate with nonfouling properties and the chain packing density must be considered for the design of nonfouling surface coatings. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Polyacrylamide brush coatings preventing microbial adhesion to silicone rubber.

    Science.gov (United States)

    Fundeanu, Irina; van der Mei, Henny C; Schouten, Arend J; Busscher, Henk J

    2008-07-15

    Silicone rubber is a frequently used biomaterial in biomedical devices and implants, yet highly prone to microbial adhesion and the development of a biomaterial-centered infection. Effective coating of silicone rubber to discourage microbial adhesion has thus far been impossible due to the hydrophobic character of its surface, surface deterioration upon treatment and instability of coatings under physiological conditions. Here we present a method to successfully grow polyacrylamide (PAAm) brushes from silicone rubber surfaces after removal of low molecular weight organic molecules (LMWOM), such as silane oligomers. PAAm brush coating did not cause any surface deterioration and discouraged microbial adhesion, even after 1-month exposure to physiological fluids. The method presented opens many new avenues for the use of silicone rubber as a biomaterial, without the risk of developing a biomaterial-centered infection.

  9. A test for Creutzfeldt-Jakob disease using nasal brushings.

    Science.gov (United States)

    Orrú, Christina D; Bongianni, Matilde; Tonoli, Giovanni; Ferrari, Sergio; Hughson, Andrew G; Groveman, Bradley R; Fiorini, Michele; Pocchiari, Maurizio; Monaco, Salvatore; Caughey, Byron; Zanusso, Gianluigi

    2014-08-07

    Definite diagnosis of sporadic Creutzfeldt-Jakob disease in living patients remains a challenge. A test that detects the specific marker for Creutzfeldt-Jakob disease, the prion protein (PrP(CJD)), by means of real-time quaking-induced conversion (RT-QuIC) testing of cerebrospinal fluid has a sensitivity of 80 to 90% for the diagnosis of sporadic Creutzfeldt-Jakob disease. We have assessed the accuracy of RT-QuIC analysis of nasal brushings from olfactory epithelium in diagnosing sporadic Creutzfeldt-Jakob disease in living patients. We collected olfactory epithelium brushings and cerebrospinal fluid samples from patients with and patients without sporadic Creutzfeldt-Jakob disease and tested them using RT-QuIC, an ultrasensitive, multiwell plate-based fluorescence assay involving PrP(CJD)-seeded polymerization of recombinant PrP into amyloid fibrils. The RT-QuIC assays seeded with nasal brushings were positive in 30 of 31 patients with Creutzfeldt-Jakob disease (15 of 15 with definite sporadic Creutzfeldt-Jakob disease, 13 of 14 with probable sporadic Creutzfeldt-Jakob disease, and 2 of 2 with inherited Creutzfeldt-Jakob disease) but were negative in 43 of 43 patients without Creutzfeldt-Jakob disease, indicating a sensitivity of 97% (95% confidence interval [CI], 82 to 100) and specificity of 100% (95% CI, 90 to 100) for the detection of Creutzfeldt-Jakob disease. By comparison, testing of cerebrospinal fluid samples from the same group of patients had a sensitivity of 77% (95% CI, 57 to 89) and a specificity of 100% (95% CI, 90 to 100). Nasal brushings elicited stronger and faster RT-QuIC responses than cerebrospinal fluid (PCreutzfeldt-Jakob disease and indicated substantial prion seeding activity lining the nasal vault. (Funded by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases and others.).

  10. A Test for Creutzfeldt–Jakob Disease Using Nasal Brushings

    Science.gov (United States)

    Orrú, Christina D.; Bongianni, Matilde; Tonoli, Giovanni; Ferrari, Sergio; Hughson, Andrew G.; Groveman, Bradley R.; Fiorini, Michele; Pocchiari, Maurizio; Monaco, Salvatore; Caughey, Byron; Zanusso, Gianluigi

    2014-01-01

    BACKGROUND Definite diagnosis of sporadic Creutzfeldt–Jakob disease in living patients remains a challenge. A test that detects the specific marker for Creutzfeldt–Jakob disease, the prion protein (PrPCJD), by means of real-time quaking-induced conversion (RT-QuIC) testing of cerebrospinal fluid has a sensitivity of 80 to 90% for the diagnosis of sporadic Creutzfeldt–Jakob disease. We have assessed the accuracy of RT-QuIC analysis of nasal brushings from olfactory epithelium in diagnosing sporadic Creutzfeldt– Jakob disease in living patients. METHODS We collected olfactory epithelium brushings and cerebrospinal fluid samples from patients with and patients without sporadic Creutzfeldt–Jakob disease and tested them using RT-QuIC, an ultrasensitive, multiwell plate–based fluorescence assay involving PrPCJD-seeded polymerization of recombinant PrP into amyloid fibrils. RESULTS The RT-QuIC assays seeded with nasal brushings were positive in 30 of 31 patients with Creutzfeldt–Jakob disease (15 of 15 with definite sporadic Creutzfeldt–Jakob disease, 13 of 14 with probable sporadic Creutzfeldt–Jakob disease, and 2 of 2 with inherited Creutzfeldt–Jakob disease) but were negative in 43 of 43 patients without Creutzfeldt–Jakob disease, indicating a sensitivity of 97% (95% confidence interval [CI], 82 to 100) and specificity of 100% (95% CI, 90 to 100) for the detection of Creutzfeldt–Jakob disease. By comparison, testing of cerebrospinal fluid samples from the same group of patients had a sensitivity of 77% (95% CI, 57 to 89) and a specificity of 100% (95% CI, 90 to 100). Nasal brushings elicited stronger and faster RT-QuIC responses than cerebrospinal fluid (PCreutzfeldt–Jakob disease and indicated substantial prion seeding activity lining the nasal vault. (Funded by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases and others.) PMID:25099576

  11. Mixed polymer brushes with thermal response amplified by roughness

    Czech Academy of Sciences Publication Activity Database

    Usov, D.; Nitschke, M.; Chytrý, Vladimír; Ulbrich, Karel; Minko, S.; Stamm, M.

    2004-01-01

    Roč. 90, - (2004), s. 622-623 ISSN 0743-0515. [American Chemical Societies Spring Meeting /227./. Anaheim, 28.03.2004-01.04.2004] R&D Projects: GA AV ČR KSK4050111 Grant - others:Deutsche Forschungsgesellschaft(DE) DFG Institutional research plan: CEZ:AV0Z4050913 Keywords : polymer brushes * thermal switching Subject RIV: CD - Macromolecular Chemistry

  12. Cholinergic urethral brush cells are widespread throughout placental mammals.

    Science.gov (United States)

    Deckmann, Klaus; Krasteva-Christ, Gabriela; Rafiq, Amir; Herden, Christine; Wichmann, Judy; Knauf, Sascha; Nassenstein, Christina; Grevelding, Christoph G; Dorresteijn, Adriaan; Chubanov, Vladimir; Gudermann, Thomas; Bschleipfer, Thomas; Kummer, Wolfgang

    2015-11-01

    We previously identified a population of cholinergic epithelial cells in murine, human and rat urethrae that exhibits a structural marker of brush cells (villin) and expresses components of the canonical taste transduction signaling cascade (α-gustducin, phospholipase Cβ2 (PLCβ2), transient receptor potential cation channel melanostatin 5 (TRPM5)). These cells serve as sentinels, monitoring the chemical composition of the luminal content for potentially hazardous compounds such as bacteria, and initiate protective reflexes counteracting further ingression. In order to elucidate cross-species conservation of the urethral chemosensory pathway we investigated the occurrence and molecular make-up of urethral brush cells in placental mammals. We screened 11 additional species, at least one in each of the five mammalian taxonomic units primates, carnivora, perissodactyla, artiodactyla and rodentia, for immunohistochemical labeling of the acetylcholine synthesizing enzyme, choline acetyltransferase (ChAT), villin, and taste cascade components (α-gustducin, PLCβ2, TRPM5). Corresponding to findings in previously investigated species, urethral epithelial cells with brush cell shape were immunolabeled in all 11 mammals. In 8 species, immunoreactivities against all marker proteins and ChAT were observed, and double-labeling immunofluorescence confirmed the cholinergic nature of villin-positive and chemosensory (TRPM5-positive) cells. In cat and horse, these cells were not labeled by the ChAT antiserum used in this study, and unspecific reactions of the secondary antiserum precluded conclusions about ChAT-expression in the bovine epithelium. These data indicate that urethral brush cells are widespread throughout the mammalian kingdom and evolved not later than about 64.5millionyears ago. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Assessment of Pain Response in Capsaicin-Induced Dynamic Mechanical Allodynia Using a Novel and Fully Automated Brushing Device

    Directory of Open Access Journals (Sweden)

    Kristian G du Jardin

    2013-01-01

    Full Text Available BACKGROUND: Dynamic mechanical allodynia is traditionally induced by manual brushing of the skin. Brushing force and speed have been shown to influence the intensity of brush-evoked pain. There are still limited data available with respect to the optimal stroke number, length, force, angle and speed. Therefore, an automated brushing device (ABD was developed, for which brushing angle and speed could be controlled to enable quantitative assessment of dynamic mechanical allodynia.

  14. Male brush-turkeys attempt sexual coercion in unusual circumstances.

    Science.gov (United States)

    Wells, David A; Jones, Darryl N; Bulger, David; Brown, Culum

    2014-07-01

    Sexual coercion by males is generally understood to have three forms: forced copulation, harassment and intimidation. We studied Australian brush-turkeys, Alectura lathami, to determine whether some male behaviours towards females at incubation mounds could be classified as aggressive, whether males were attempting sexual coercion and, if so, whether the coercion was successful. We found that some male behaviours towards females were significantly more likely to be followed by the cessation of female mound activity, and hence could be classified as aggressive, while others were significantly more likely to be followed by the commencement of female mound activity, and hence could be classified as enticing. Copulation was preceded by higher rates of male enticement and by higher rates of certain types of male aggression. It therefore seemed that males were attempting sexual coercion. There was little evidence, however, that this combination of coercion and enticement was successful in obtaining copulations. While forced copulation did occur, it was infrequent, and no evidence could be found for intimidation. We conclude that harassment is the primary form of sexual coercion by male brush-turkeys. Although sexual coercion is understood to be a sub-optimal tactic, brush-turkey sexual coercion was employed as a primary tactic by dominant males who owned incubation mounds. One possible explanation for this apparent paradox is that aggression is the default solution for social conflicts in this species, and hence can be interpreted as a behavioural syndrome. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Reduced Water Density in a Poly(ethylene oxide) Brush

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hoyoung; Kim, Dae Hwan; Park, Hae-Woong; Mahynski, Nathan A.; Kim, Kyungil; Meron, Mati; Lin, Binhua; Won, You-Yeon (Purdue); (UC)

    2012-09-05

    A model poly(ethylene oxide) (PEO) brush system, prepared by spreading a poly(ethylene oxide)-poly(n-butyl acrylate) (PEO-PnBA) amphiphilic diblock copolymer onto an air-water interface, was investigated under various grafting density conditions by using the X-ray reflectivity (XR) technique. The overall electron density profiles of the PEO-PnBA monolayer in the direction normal to the air-water interface were determined from the XR data. From this analysis, it was found that inside of the PEO brush, the water density is significantly lower than that of bulk water, in particular, in the region close to the PnBA-water interface. Separate XR measurements with a PnBA homopolymer monolayer confirm that the reduced water density within the PEO-PnBA monolayer is not due to unfavorable contacts between the PnBA surface and water. The above result, therefore, lends support to the notion that PEO chains provide a hydrophobic environment for the surrounding water molecules when they exist as polymer brush chains.

  16. Technology of high-speed combined machining with brush electrode

    Science.gov (United States)

    Kirillov, O. N.; Smolentsev, V. P.; Yukhnevich, S. S.

    2018-03-01

    The new method was proposed for high-precision dimensional machining with a brush electrode when the true position of bundles of metal wire is adjusted by means of creating controlled centrifugal forces appeared due to the increased frequency of rotation of a tool. There are the ultimate values of circumferential velocity at which the bundles are pressed against a machined area of a workpiece in a stable manner despite the profile of the machined surface and variable stock of the workpiece. The special aspects of design of processing procedures for finishing standard parts, including components of products with low rigidity, are disclosed. The methodology of calculation and selection of processing modes which allow one to produce high-precision details and to provide corresponding surface roughness required to perform finishing operations (including the preparation of a surface for metal deposition) is presented. The production experience concerned with the use of high-speed combined machining with an unshaped tool electrode in knowledge-intensive branches of the machine-building industry for different types of production is analyzed. It is shown that the implementation of high-speed dimensional machining with an unshaped brush electrode allows one to expand the field of use of the considered process due to the application of a multipurpose tool in the form of a metal brush, as well as to obtain stable results of finishing and to provide the opportunities for long-term operation of the equipment without its changeover and readjustment.

  17. Structural analysis of paintings based on brush strokes

    Science.gov (United States)

    Sablatnig, Robert; Kammerer, Paul; Zolda, Ernestine

    1998-05-01

    The origin of works of art can often not be attributed to a certain artist. Likewise it is difficult to say whether paintings or drawings are originals or forgeries. In various fields of art new technical methods are used to examine the age, the state of preservation and the origin of the materials used. For the examination of paintings, radiological methods like X-ray and infra-red diagnosis, digital radiography, computer-tomography, etc. and color analyzes are employed to authenticate art. But all these methods do not relate certain characteristics in art work to a specific artist -- the artist's personal style. In order to study this personal style of a painter, experts in art history and image processing try to examine the 'structural signature' based on brush strokes within paintings, in particular in portrait miniatures. A computer-aided classification and recognition system for portrait miniatures is developed, which enables a semi- automatic classification and forgery detection based on content, color, and brush strokes. A hierarchically structured classification scheme is introduced which separates the classification into three different levels of information: color, shape of region, and structure of brush strokes.

  18. How pre-school children learn to brush their teeth in Sharjah, United Arab Emirates.

    Science.gov (United States)

    Khadri, F A; Gopinath, V K; Hector, M P; Davenport, E S

    2010-05-01

    The objective of this cross-sectional study was to assess tooth brushing habits of pre-school children and to determine the role and amount of supervision given to them by their parents. One hundred pre-school children below 6 years were selected from Maternal and Child Health Center, Sharjah (United Arab Emirates, UAE). A standard piloted questionnaire was used to collect socio-demographic details and information on oral hygiene practise. Tooth brushing was stared at a mean age of 16 months. Thirty-seven per cent of the pre-schoolers used a toothbrush for cleaning their teeth and the brushing habits were mainly (70%) introduced by mothers. The majority (80%) of children's tooth brushing at the age of 3 years and above was supervised by mothers. Younger children were frequently supervised in tooth brushing than older children (P brushing at a mean age of 16 months. Mothers played a pivotal role in introducing and teaching the child how to brush. There was no positive correlation between the brushing behaviour of the mothers and their children. In most cases, the children's brushing was supervised by their mother when they were above 25 months of age. In children less than 12 months of age tooth brushing was not started at all.

  19. Boundary lubrication by brushed salivary conditioning films and their degree of glycosylation.

    Science.gov (United States)

    Veeregowda, Deepak H; van der Mei, Henny C; de Vries, Joop; Rutland, Mark W; Valle-Delgado, Juan J; Sharma, Prashant K; Busscher, Henk J

    2012-10-01

    Toothbrushing, though aimed at biofilm removal, also affects the lubricative function of adsorbed salivary conditioning films (SCFs). Different modes of brushing (manual, powered, rotary-oscillatory or sonically driven) influence the SCF in different ways. Our objectives were to compare boundary lubrication of SCFs after different modes of brushing and to explain their lubrication on the basis of their roughness, dehydrated layer thickness, and degree of glycosylation. A pilot study was performed to relate in vitro lubrication with mouthfeel in human volunteers. Coefficient of friction (COF) on 16-h-old SCFs after manual, rotary-oscillatory, and sonically driven brushing was measured using colloidal probe atomic force microscopy (AFM). AFM was also used to assess the roughness of SCFs prior to and after brushing. Dehydrated layer thicknesses and glycosylation of the SCFs were determined using X-ray photoelectron spectroscopy. Mouthfeel after manual and both modes of powered brushing were evaluated employing a split-mouth design. Compared with unbrushed and manually or sonically driven brushed SCFs, powered rotary-oscillatory brushing leads to deglycosylation of the SCF, loss of thickness, and a rougher film. Concurrently, the COF of a powered rotary-oscillatory brushed SCF increased. Volunteers reported a slightly preferred mouthfeel after sonic brushing as compared to powered rotating-oscillating brushing. Deglycosylation and roughness increase the COF on SCFs. Powered rotary-oscillatory brushing can deglycosylate a SCF, leading to a rougher film surface as compared with manual and sonic brushing, decreasing the lubricative function of the SCF. This is consistent with clinical mouthfeel evaluation after different modes of brushing.

  20. The effect of brushing with toothpaste containing nano calcium carbonate upon nanofill composite resin surface roughness

    Science.gov (United States)

    Ramadhani, A. M.; Herda, E.; Triaminingsih, S.

    2017-08-01

    This study aims to determine the effect of brushing with toothpaste containing nanocalcium carbonate on the roughness of nanofill composite resin surface. Brushing was conducted with 3 types of materials for 3 consecutive brushing periods of 10 minutes each. Surface roughness was measured using a surface-roughness tester and the results were analyzed using the repeated ANOVA and the one-way ANOVA test. The surface morphology was observed using SEM after 3 months’ worth of brushing with the 3 materials. It was found that the nanofill composite resin surface-roughness value increased significantly (p<0.005) after brushing with toothpaste containing nano calcium carbonate for 3 months, but the value was not as high as that obtained when brushing with other types of toothpaste.

  1. Gastric and intestinal surgery.

    Science.gov (United States)

    Fossum, Theresa W; Hedlund, Cheryl S

    2003-09-01

    Gastric surgery is commonly performed to remove foreign bodies and correct gastric dilatation-volvulus and is less commonly performed to treat gastric ulceration or erosion, neoplasia, and benign gastric outflow obstruction. Intestinal surgery, although commonly performed by veterinarians, should never be considered routine. The most common procedures of the small intestinal tract performed in dogs and cats include enterotomy and resection/anastomosis. Surgery of the large intestine is indicated for lesions causing obstruction, perforations, colonic inertia, or chronic inflammation.

  2. Intestinal parasites and tuberculosis

    Directory of Open Access Journals (Sweden)

    Anuar Alonso Cedeño-Burbano

    2017-10-01

    Conclusions: The available evidence was insufficient to affirm that intestinal parasites predispose to developing tuberculous. The studies carried out so far have found statistically insignificant results.

  3. Aymara paradiplomacy: Empowerment in the border

    Directory of Open Access Journals (Sweden)

    Gilberto Aranda Bustamante

    2017-01-01

    Full Text Available This article analyzes the border paradiplomacy used by more than 50 municipalities from Bolivia, Chile and Peru, named “Aymaras without Borders Strategic Alliance”. In spite of the differentiated historical construction of national identities, according to a literature review, it could be argued that there is an unprecedented border relation between these three countries. Furthermore, it is possible to conclude that this non-violent strategy has been successful in the last 15 years.

  4. A model for international border management systems.

    Energy Technology Data Exchange (ETDEWEB)

    Duggan, Ruth Ann

    2008-09-01

    To effectively manage the security or control of its borders, a country must understand its border management activities as a system. Using its systems engineering and security foundations as a Department of Energy National Security Laboratory, Sandia National Laboratories has developed such an approach to modeling and analyzing border management systems. This paper describes the basic model and its elements developed under Laboratory Directed Research and Development project 08-684.

  5. Tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students

    Directory of Open Access Journals (Sweden)

    Clement C. Azodo

    2010-08-01

    Full Text Available Objective: To determine the tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students. Methods: A descriptive cross-sectional study of students of Federal School of Dental Therapy and Technology Enugu, Nigeria. Self-administered questionnaire was used to obtain information on demography, frequency, duration and technique of tooth brushing and tongue cleaning as well as information on consumption of snacks. Results: A total of 242 students responded. Dental technology students made up 52.5% of the respondents and dental therapist in training made up 47.5%. Majority (63.2% of the respondents considered the strength of tooth brush when purchasing a tooth brush and 78.9% use tooth brushes with medium strength. Seven-tenth (71.9% of the respondents brush their teeth twice daily and 52.1% brush for 3–5 minutes. About one-third (30.2% brush their teeth in front of a mirror. Chewing stick was used by 51.7% of respondents in addition to the use of tooth brush. Tongue cleaning was done by 94.2% with only 9.5% using a tongue cleaner. Only 20.2% reported regular snacks consumption. Nine-tenth (90.4% of respondents were previously involved in educating others, apart from their colleagues, on tooth brushing. Conclusion: This survey revealed that most of the dental therapy and technology students had satisfactory tooth-brushing behaviour. The zeal to educate others about proper tooth brushing revealed in this study suggests that the students may be helpful in oral health promotion.

  6. Comparison between observed children's tooth brushing habits and those reported by mothers.

    Science.gov (United States)

    Martins, Carolina C; Oliveira, Maria J; Pordeus, Isabela A; Paiva, Saul M

    2011-09-03

    Information bias can occur in epidemiological studies and compromise scientific outcomes, especially when evaluating information given by a patient regarding their own health. The oral habits of children reported by their mothers are commonly used to evaluate tooth brushing practices and to estimate fluoride intake by children. The aim of the present study was to compare observed tooth-brushing habits of young children using fluoridated toothpaste with those reported by mothers. A sample of 201 mothers and their children (aged 24-48 months) from Montes Claros, Brazil, took part in a cross-sectional study. At day-care centres, the mothers answered a self-administered questionnaire on their child's tooth-brushing habits. The structured questionnaire had six items with two to three possible answers. An appointment was then made with each mother/child pair at day-care centres. The participants were asked to demonstrate the tooth-brushing practice as usually performed at home. A trained examiner observed and documented the procedure. Observed tooth brushing and that reported by mothers were compared for overall agreement using Cohen's Kappa coefficient and the McNemar test. Cohen's Kappa values comparing mothers' reports and tooth brushing observed by the examiner ranged from poor-to-good (0.00-0.75). There were statistically significant differences between observed tooth brushing habits and those reported by mothers (p brushed their teeth alone (33.8%) and those who did not rinse their mouths during brushing (42.0%) were higher than those reported by the mothers (12.1%, 18.9% and 6.5%, respectively; p brushing and mothers' reports. Moreover, the different methods of estimation resulted in differences in the frequencies of tooth brushing habits, indicative of reporting bias. Data regarding children's tooth-brushing habits as reported by mothers should be considered with caution in epidemiological surveys on fluoridated dentifrice use and the risk of dental fluorosis.

  7. Tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students.

    Science.gov (United States)

    Azodo, Clement C; Ehizele, Adebola O; Umoh, Agnes; Ojehanon, Patrick I; Akhionbare, Osagie; Okechukwu, Robinson; Igbinosa, Lawrence

    2010-08-12

    To determine the tooth brushing, tongue cleaning and snacking behaviour of dental technology and therapist students. A descriptive cross-sectional study of students of Federal School of Dental Therapy and Technology Enugu, Nigeria. Self-administered questionnaire was used to obtain information on demography, frequency, duration and technique of tooth brushing and tongue cleaning as well as information on consumption of snacks. A total of 242 students responded. Dental technology students made up 52.5% of the respondents and dental therapist in training made up 47.5%. Majority (63.2%) of the respondents considered the strength of tooth brush when purchasing a tooth brush and 78.9% use tooth brushes with medium strength. Seven-tenth (71.9%) of the respondents brush their teeth twice daily and 52.1% brush for 3-5 minutes. About one-third (30.2%) brush their teeth in front of a mirror. Chewing stick was used by 51.7% of respondents in addition to the use of tooth brush. Tongue cleaning was done by 94.2% with only 9.5% using a tongue cleaner. Only 20.2% reported regular snacks consumption. Nine-tenth (90.4%) of respondents were previously involved in educating others, apart from their colleagues, on tooth brushing. This survey revealed that most of the dental therapy and technology students had satisfactory tooth-brushing behaviour. The zeal to educate others about proper tooth brushing revealed in this study suggests that the students may be helpful in oral health promotion.

  8. Nuclear risk behind the border?

    International Nuclear Information System (INIS)

    Varjoranta, T.

    1995-01-01

    The condition of nuclear wastes and facilities in Russia and in the Baltic countries arouses concern in Finland. Russia has two large nuclear power plants, nuclear weapons, over 300 nuclear submarine reactors and more than ten icebreaker reactors in close proximity to Finland's eastern border. The Lithuanian Ingalina nuclear power plant is also situated close to Finland. Following the Chernobyl accident, considerable improvements have been made to the technology and safety culture of Russian nuclear power plants, for instance, through international support programmes. The unstable social climate in Russia is, however, slowing progress down. Yet it is certain that no accident in the power plants near Finland's borders would cause immediate health risks in Finland, or would threaten the health of large numbers of people in the long term, either. Russia has not always taken proper care of its nuclear waste. In particular, spent fuel from nuclear submarines stored in Northern Russia causes problems. Russians have disposed of some waste by dumping ship reactors, with their fuel, into the Arctic Ocean. Some nuclear-powered submarines have sunk with all their crew. Russia has also conducted many nuclear tests in the vicinity of Finland. (orig.)

  9. Human intestinal mucus proteins isolated by transanal irrigation and proctosigmoidoscopy

    Directory of Open Access Journals (Sweden)

    Paola Andrea Gómez Buitrago

    2014-10-01

    Full Text Available Human intestinal mucus essentially consists of a network of Mucin2 glycoproteins embedded in many lower molecular weight proteins. This paper contributes to the proteomic study of human intestinal mucus by comparing two sample collection methods (transanal irrigation and brush cytology during proctosigmoidoscopy and analysis techniques (electrophoresis and digestion in solution. The entire sample collection and treatment process is explained, including protein extraction, digestion and desalination and peptide characterisation using a nanoAcquity UPLC chromatograph coupled to an HDMS spectrometer equipped with a nanoESI source. Collecting mucus via transanal irrigation provided a larger sample volume and protein concentration from a single patient. The proctosigmoidoscopy sample could be analysed via digestion in solution after depleting albumin. The analysis indicates that a simple mucus lysis method can evaluate the electrophoresis and digestion in solution techniques. Studying human intestinal mucus complexes is important because they perform two essential survival functions for humans as the first biochemical and physical defences for the gastrointestinal tract and a habitat for intestinal microbiota, which are primarily hosted in the colon and exceeds the human genetic information and cell number 100- and 10-fold (1.

  10. The cross-border cooperation agreement

    Directory of Open Access Journals (Sweden)

    Cătălin-Silviu SĂRARU

    2011-06-01

    Full Text Available This study aims to achieve a short analysis of cross-border cooperation agreements between territorial-administrative units in the border areas of Romania and similar structures in neighboring states. The article investigates the form they takes these agreements – contract or treaty –, the role of multinational enterprises and the law applicable to transnational contracts, the cross-border cooperation agreement governed by Law no. 215/2001 on local public administration and its legal nature. The end of the article is discussed cross-border cooperation in international documents signed by Romania with its neighbors.

  11. Border Crossing/Entry Data - Border Crossing/Entry Data Time Series tool

    Data.gov (United States)

    Department of Transportation — The dataset is known as “Border Crossing/Entry Data.” The Bureau of Transportation Statistics (BTS) Border Crossing/Entry Data provides summary statistics to the...

  12. Behavioral Determinants of Brushing Young Children's Teeth: Implications for Anticipatory Guidance

    Science.gov (United States)

    Huebner, Colleen E.; Riedy, Christine A.

    2010-01-01

    Purpose The purposes of this study were to identify parents' motivation, support, and barriers to twice daily tooth-brushing of infants and preschool-age children and to discover new approaches to encourage this important health behavior. Methods Qualitative interviews were conducted with 44 rural parents about tooth-brushing habits and experiences. Results Forty of 44 parents reported that they had begun to brush their child's teeth; 24 (55%) reported brushing twice a day or more. Parents who brushed twice a day, vs less often, were more likely to describe specific skills to overcome barriers; they expressed high self-efficacy and held high self-standards for brushing. Parents who brushed their children's teeth less than twice daily were more likely to: hold false beliefs about the benefits of twice daily tooth-brushing; report little normative pressure or social support for the behavior; have lower self-standards; describe more external constraints; and offer fewer ideas to overcome barriers. Conclusions The findings support an integrative framework in which barriers and support for parents' twice daily brushing of their young children's teeth are multiple and vary among individuals. Knowledge of behavioral determinants specific to individual parents could strengthen anticipatory guidance and recommendations about at-home oral hygiene of young children. PMID:20298653

  13. Programming nanostructures of polymer brushes by dip-pen nanodisplacement lithography (DNL)

    Science.gov (United States)

    Liu, Xuqing; Li, Yi; Zheng, Zijian

    2010-12-01

    We report a facile and versatile scanning probe based approach--dip-pen nanodisplacement lithography (DNL)--for manipulating nanostructures of polymer brushes. Nanostructured polymer brushes with sizes as small as 25 nm are made by DNL patterning of the initiator molecules and subsequent surface-initiated polymerization. Nanoconfinement effects including chain collapsing and spreading are observed in the nanopatterned polymer brushes. In addition to chemical structure, size, topography and shape, our approach can also readily program the grafting density, chain configuration, hierarchical structure and multiplexing of the polymer brushes, which allows for the realization of complex chemical surfaces.We report a facile and versatile scanning probe based approach--dip-pen nanodisplacement lithography (DNL)--for manipulating nanostructures of polymer brushes. Nanostructured polymer brushes with sizes as small as 25 nm are made by DNL patterning of the initiator molecules and subsequent surface-initiated polymerization. Nanoconfinement effects including chain collapsing and spreading are observed in the nanopatterned polymer brushes. In addition to chemical structure, size, topography and shape, our approach can also readily program the grafting density, chain configuration, hierarchical structure and multiplexing of the polymer brushes, which allows for the realization of complex chemical surfaces. Electronic supplementary information (ESI) available: LFM images of MUDBr patterns; digital image of irregular polymer brushes grown on gold caused by random diffusion of MUDBr through the air. See DOI: 10.1039/c0nr00565g

  14. Oral hygiene management of autistic population -an investigation of their tooth brushing-

    OpenAIRE

    田邊, 義浩; 石倉, 優香; 野田, 忠; Tanabe, Yoshihiro; Ishikura, Yuuka; Noda, Tadashi

    1996-01-01

    The purpose of this study was to know the factors influencing on tooth brushing of autistic population. The subjects were 17 utistic patients who commuted to a welfare institution in Niigata city, aged from 16 to 27 years old. The parents of the subjects were asked to answer a questionnaire about the way of tooth brushing in their family life. The subjects were tested for their understanding about the mean of tooth brushing by some series of picture cards of oral health, tooth brushing and de...

  15. Behavioral determinants of brushing young children's teeth: implications for anticipatory guidance.

    Science.gov (United States)

    Huebner, Colleen E; Riedy, Christine A

    2010-01-01

    The purposes of this study were to identify parents' motivation, support, and barriers to twice daily tooth-brushing of infants and preschool-age children and to discover new approaches to encourage this important health behavior. Qualitative interviews were conducted with 44 rural parents about tooth-brushing habits and experiences. Forty of 44 parents reported that they had begun to brush their child's teeth; 24 (55%) reported brushing twice a day or more. Parents who brushed twice a day, vs less often, were more likely to describe specific skills to overcome barriers; they expressed high self-efficacy and held high self-standards for brushing. Parents who brushed their children's teeth less than twice daily were more likely to: hold false beliefs about the benefits of twice daily tooth-brushing; report little normative pressure or social support for the behavior; have lower self-standards; describe more external constraints; and offer fewer ideas to overcome barriers. The findings support an integrative framework in which barriers and support for parents' twice daily brushing of their young children's teeth are multiple and vary among individuals. Knowledge of behavioral determinants specific to individual parents could strengthen anticipatory guidance and recommendations about at-home oral hygiene of young children.

  16. Analysis of carbon fiber brush loading in anodes on startup and performance of microbial fuel cells

    KAUST Repository

    Hutchinson, Adam J.

    2011-11-01

    Flat carbon anodes placed near a cathode in a microbial fuel cell (MFC) are adversely affected by oxygen crossover, but graphite fiber brush anodes placed near the cathode produce high power densities. The impact of the brush size and electrode spacing was examined by varying the distance of the brush end from the cathode and solution conductivity in multiple MFCs. The startup time was increased from 8 ± 1 days with full brushes (all buffer concentrations) to 13 days (50 mM), 14 days (25 mM) and 21 days (8 mM) when 75% of the brush anode was removed. When MFCs were all first acclimated with a full brush, up to 65% of the brush material could be removed without appreciably altering maximum power. Electrochemical impedance spectroscopy (EIS) showed that the main source of internal resistance (IR) was diffusion resistance, which together with solution resistance reached 100 Ω. The IR using EIS compared well with that obtained using the polarization data slope method, indicating no major components of IR were missed. These results show that using full brush anodes avoids adverse effects of oxygen crossover during startup, although brushes are much larger than needed to sustain high power. © 2011 Elsevier B.V.

  17. Contaminated tooth brushes-potential threat to oral and general health.

    Science.gov (United States)

    Naik, Rashmi; Ahmed Mujib, B R; Telagi, Neethu; Anil, B S; Spoorthi, B R

    2015-01-01

    Tooth brushing is most common method of maintaining oral hygiene. In removing plaque and other soft debris from the teeth, tooth brushes become contaminated with bacteria, blood, saliva and oral debris. These contaminated tooth brushes can be a source of infection. The aim of the present study was to evaluate the presence of microorganisms in the tooth brushes and to investigate the effect of disinfectants such as chlorhexidine gluconate, sodium hypochlorite and water to decontaminate them. Twenty-one children were asked to brush their teeth for 5 days with a tooth brush. The tooth brushes were put in Robertson's Cooked Meat broth and were observed for growth of Streptococcal microorganisms. These tooth brushes were then placed in disinfectants such as 0.2% chlorhexidine gluconate (Group I), 1% sodium hypochlorite (Group II) and water (Group III) for 24 hrs and then cultured again. Reduction of growth of microorganisms was seen in Group I, Group II and remnants of growth seen in Group III. We conclude that the use of disinfectant for a tooth brush is a must for every individual at least at regular intervals.

  18. Contaminated tooth brushes-potential threat to oral and general health

    Directory of Open Access Journals (Sweden)

    Rashmi Naik

    2015-01-01

    Full Text Available Background: Tooth brushing is most common method of maintaining oral hygiene. In removing plaque and other soft debris from the teeth, tooth brushes become contaminated with bacteria, blood, saliva and oral debris. These contaminated tooth brushes can be a source of infection. Aims and objectives: The aim of the present study was to evaluate the presence of microorganisms in the tooth brushes and to investigate the effect of disinfectants such as chlorhexidine gluconate, sodium hypochlorite and water to decontaminate them. Materials and Methods: Twenty-one children were asked to brush their teeth for 5 days with a tooth brush. The tooth brushes were put in Robertson′s Cooked Meat broth and were observed for growth of Streptococcal microorganisms. These tooth brushes were then placed in disinfectants such as 0.2% chlorhexidine gluconate (Group I, 1% sodium hypochlorite (Group II and water (Group III for 24 hrs and then cultured again. Reduction of growth of microorganisms was seen in Group I, Group II and remnants of growth seen in Group III. Conclusion: We conclude that the use of disinfectant for a tooth brush is a must for every individual at least at regular intervals.

  19. Is the international border effect larger than the domestic border effect? Evidence from US trade

    OpenAIRE

    Cletus C. Coughlin; Dennis Novy

    2012-01-01

    Many studies have found that international borders represent large barriers to trade. But how do international borders compare to domestic border barriers? We investigate international and domestic border barriers in a unified framework. We consider a data set of exports from individual US states to foreign countries and combine it with trade flows between and within US states. After controlling for distance and country size, we estimate that relative to state-to-state trade, crossing an indi...

  20. Learning Mobility Challenging Borders: Cross-border Experiences of eastern European Immigrants in Spain

    OpenAIRE

    Marcu, Silvia

    2016-01-01

    [EN] This article examines the cross-border mobility practices of eastern European immigrants across and within European Union (EU) borders, taking into account the changes in the patterns of the EU border regime, which have affected mobility in the last 20 years. Drawing on empirical research with references to in-depth qualitative interviews of eastern immigrants in Spain, this article highlights the ways in which the emerging models of cross-border mobility management are producing new geo...

  1. The Borders of "Shopluk" and/or Shops without Borders

    Directory of Open Access Journals (Sweden)

    P. Hristov

    2015-08-01

    Full Text Available A historic and cultural region exists at the heart of the Balkans, known in geographic and ethnographic research as Shopluk. This is a region in which, over the last 150 years, state boundaries were moved several times as a result of 5 different wars. Today, the historic Shopluk is where the borders of three nations converge – Republic of Bulgaria, Republic of Serbia and the Republic of Macedonia – and, during the last decade, the region was declared one of the “Euroregions” on the Balkans. Despite the historical similarities in traditional culture and language of this population, in the 19th century it became a subject of nationalist ambitions and a propaganda “wars” between the new national states of Serbia and Bulgaria. The joining of Bulgarian-inhabited parts of Shopluk (the regions of today’s Dimitrovgrad and Bosilegrad in Serbia to the Kingdom of Serbs, Slovenes and Croats in 1919 created a long-lasting tension between the two countries, some residues of which can be felt in everyday relations even today. On the other hand, it has been a century-long tradition for men in this region to take part in seasonal labour migrations all over the Balkan Peninsula, despite political borders. In this way, preserving their cultural and lingual specifics, the groups of seasonal workers – migrants from Shopluk, became a bridge for cultural interaction and exchange with other regions in the neighbour countries. Even though today the population of Shopluk exhibits different national identities, historical similarities in culture and language can turn the Euroregion between Nish, Sofia and Skopje from one of the poorest on the Balkans to one of the most integrated and prosperous.

  2. The Armchair at the Borders: The "Messy" Ideas of Borders and Border Epistemologies within Multicultural Science Education Scholarship

    Science.gov (United States)

    Carter, Lyn

    2010-01-01

    This paper aims to further articulate multicultural science education scholarship. In particular, it explores the notions of borders and border epistemologies as intellectual resources to think again about the challenges of science education in the global world that demand more sophisticated concepts to unravel some of its complexities. It…

  3. International Issues, High-Stakes Testing, and Border Pedagogy: Social Studies at Border High School

    Science.gov (United States)

    Cashman, Timothy G.; McDermott, Benjamin R.

    2013-01-01

    A recently constructed border wall stands within walking distance of Border High School (BHS) and was created to impede the flow of people, goods, fauna, and contraband from Mexico into the United States (U.S.). The reality, however, is that this geopolitical border is fluid, allowing connections between sociopolitical zones. The researchers…

  4. A Modified Tactile Brush Algorithm for Complex Touch Gestures

    Energy Technology Data Exchange (ETDEWEB)

    Ragan, Eric [Texas A& M University

    2015-01-01

    Several researchers have investigated phantom tactile sensation (i.e., the perception of a nonexistent actuator between two real actuators) and apparent tactile motion (i.e., the perception of a moving actuator due to time delays between onsets of multiple actuations). Prior work has focused primarily on determining appropriate Durations of Stimulation (DOS) and Stimulus Onset Asynchronies (SOA) for simple touch gestures, such as a single finger stroke. To expand upon this knowledge, we investigated complex touch gestures involving multiple, simultaneous points of contact, such as a whole hand touching the arm. To implement complex touch gestures, we modified the Tactile Brush algorithm to support rectangular areas of tactile stimulation.

  5. adhesive intestinal obstruction

    African Journals Online (AJOL)

    2006-06-01

    Jun 1, 2006 ... ABSTRACT. Background: Adhesions after abdominal and pelvic surgery are a major cause of intestinal obstruction in the western world and the pathology is steadily gaining prominence in our practice. Objective: To determine the magnitude of adhesive intestinal obstruction; to determine the types.

  6. Intestinal Barrier and Behavior.

    Science.gov (United States)

    Julio-Pieper, M; Bravo, J A

    2016-01-01

    The intestinal barrier function contributes to gut homeostasis by modulating absorption of water, electrolytes, and nutrients from the lumen into the circulation while restricting the passage of noxious luminal substances and microorganisms. Chronic conditions such as rheumatoid arthritis, inflammatory bowel disease, and celiac disease are associated to intestinal barrier dysfunction. Here, the hypothesis is that a leaky intestinal wall allowing for indiscriminate passage of intraluminal compounds to the vascular compartment could in turn lead to systemic inflammation. An increasing number of studies are now investigating the association between gut permeability and CNS disorders, under the premise that translocation of intestinal luminal contents could affect CNS function, either directly or indirectly. Still, it is unknown whether disruption of intestinal barrier is a causative agent or a consequence in these situations. Here, we discuss the latest evidence pointing to an association between increased gut permeability and disrupted behavioral responses. © 2016 Elsevier Inc. All rights reserved.

  7. Strongly stretched protein resistant poly(ethylene glycol) brushes prepared by grafting-to.

    Science.gov (United States)

    Emilsson, Gustav; Schoch, Rafael L; Feuz, Laurent; Höök, Fredrik; Lim, Roderick Y H; Dahlin, Andreas B

    2015-04-15

    We present a new grafting-to method for resistant "non-fouling" poly(ethylene glycol) brushes, which is based on grafting of polymers with reactive end groups in 0.9 M Na2SO4 at room temperature. The grafting process, the resulting brushes, and the resistance toward biomolecular adsorption are investigated by surface plasmon resonance, quartz crystal microbalance, and atomic force microscopy. We determine both grafting density and thickness independently and use narrow molecular weight distributions which result in well-defined brushes. High density (e.g., 0.4 coils per nm(2) for 10 kDa) and thick (40 nm for 20 kDa) brushes are readily achieved that suppress adsorption from complete serum (10× dilution, exposure for 50 min) by up to 99% on gold (down to 4 ng/cm(2) protein coverage). The brushes outperform oligo(ethylene glycol) monolayers prepared on the same surfaces and analyzed in the same manner. The brush heights are in agreement with calculations based on a simple model similar to the de Gennes "strongly stretched" brush, where the height is proportional to molecular weight. This result has so far generally been considered to be possible only for brushes prepared by grafting-from. Our results are consistent with the theory that the brushes act as kinetic barriers rather than efficient prevention of adsorption at equilibrium. We suggest that the free energy barrier for passing the brush depends on both monomer concentration and thickness. The extraordinary simplicity of the method and good inert properties of the brushes should make our results widely applicable in biointerface science.

  8. Tooth brushing motion patterns with manual and powered toothbrushes-a randomised video observation study.

    Science.gov (United States)

    Ganss, C; Duran, R; Winterfeld, T; Schlueter, N

    2018-03-01

    Systematic reviews have shown that powered toothbrushes (PTs) are more effective than manual toothbrushes (MTs), but with only minor effect sizes. Whether PTs are used adequately, however, has not been investigated so far. The aim of the present study was therefore to analyse motion habits with PT in comparison to MT toothbrushes by video observation. One hundred subjects were enrolled in this observational trial and brushed their teeth in randomised order with a MT and PT while being video-filmed, resulting in 95 analysable sets of recordings. Parameters of interest were brushing duration (s; median (min;max)), type of brushing strokes, area of brushing, changes between areas (n; median (min;max)) and brushing sequence. Brushing duration was 145 s (60;354) and 135 s (48;271) for PT and MT, respectively (p ≤ 0.001). Subjects brushed vestibular surfaces completely, but reached oral surfaces to a much lesser extent, regardless of the toothbrush type. With both toothbrushes, subjects moved frequently between areas (MT 35 (14;79); PT 33 (14;85); n.s.) and brushed predominantly with circling and horizontal strokes; with the PT, 50.5% of the subjects spent only brushing duration with passive brushing (positioning the brush head on the teeth with ≤2 movements/s). Intra-individual motion patterns were similar with both MT and PT, and most subjects persisted in their habitual motion patterns regardless of the toothbrush type. The use of PT and MT may need intensive training and supervision from oral hygiene educators in order to help subjects taking full advantage from these devices.

  9. Efficacy of straight versus angled interdental brushes on interproximal tooth cleaning: a randomized controlled trial.

    Science.gov (United States)

    Jordan, R A; Hong, H M; Lucaciu, A; Zimmer, S

    2014-05-01

    To investigate interproximal biofilm reduction with an angled interdental brush as compared to a straight interdental brush (standard control) in a clinical, single-centre, single-blind, controlled, parallel-group trial. Recruitment and examinations of the subjects were performed at the Witten/Herdecke University School of Dental Medicine. 128 volunteers, aged 20-65 years, were recruited and stratified according to sex and age. Two groups with 64 subjects each used either straight (standard control) or angled (test group) handgripped interdental toothbrushes of the same bristle stiffness. After a 12-day home-care habituation period, participants received a professional tooth cleaning followed by a 48-h plaque regrowth period. At the intervention appointment, plaque was recorded with a fluorescent revelator and soft tissue damage was noted (T0 ). Interdental brushing was performed by the participant for 2 min, and clinical parameters were recorded again (T1 ). The primary efficacy end point was the difference in modified Proximal Plaque Index (mPPI) after brushing compared to baseline. Secondary efficacy end points were mPPI differences in subgroups (anterior vs. posterior teeth; vestibular vs. oral tooth surfaces). Safety end point was the Danser gingival abrasion index (DI). mPPI showed lower scores after brushing within all (sub)groups (P brushing efficacy (ΔT0  - T1 ) in subjects using straight interdental brushes was significantly higher as compared to angled interdental brushes (P brushes were significantly more effective in posterior teeth, when used from vestibular and from oral tooth surfaces (P teeth and concerning soft tissue damage. Straight interdental brushes may better remove plaque interproximally when compared to angled interdental brushes. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Researching Transfronterizo Literacies in Texas Border Colonias

    Science.gov (United States)

    Smith, Patrick H.; Murillo, Luz A.

    2012-01-01

    This study examines literacies practiced in bilingual households located in emerging communities along the Texas-Mexico border known as border colonias. Drawing on theoretical notions of space as geographic and temporal, the simultaneity of global and local forces at work in colonias, and expressions of agency that are "in between"…

  11. Sprouting of dormant buds on border trees

    Science.gov (United States)

    G.R., Jr. Trimble; H. Clay Smith; H. Clay Smith

    1970-01-01

    As part of an evaluation of silvicultura1 systems used in managing Appalachian hardwoods, we are studying degrade of border trees surrounding harvest-cut openings made in the patch cutting and group selection systems. One facet of this research dealt with determining what portion of visually evident dormant buds on border tree boles sprouted when the openings were cut...

  12. Externalization and Border-induced Displacement

    DEFF Research Database (Denmark)

    Lemberg-Pedersen, Martin

    in-depth research of the privatization of border control through the cases of G4S, Finmeccanica and the EU’s EUROSUR system. The chapter links externalization of border control with European state-driven export markets and shows how states’ export credit agencies, the arms industry...

  13. Border Pedagogy Cafes: Grassroots Conversations that Matter

    Science.gov (United States)

    Necochea, Juan; Cline, Zulmara

    2008-01-01

    This exploratory study uses qualitative methods to analyze the impact of conversations in the Border Pedagogy "Cafes" on more than 500 binational educators from the Tijuana/San Diego area on the U.S.-Mexico border. Four important themes emerged from the analysis that describe the impact of the cafes and offer a strong foundation on which…

  14. BEYOND THE BORDER WAR: NEW PERSPECTIVES ON ...

    African Journals Online (AJOL)

    hennie

    they viewed as necessary cross-border-, deep penetration and/or pre-emptive strikes against the People's Liberation ... Beyond the Border War: New Perspectives on Southern Africa's Late Cold War. Conflicts falls in a .... Sasha Gear writes about veterans and the effect of the war on them and those close to them - or rather, ...

  15. Interplay between river dynamics and international borders

    NARCIS (Netherlands)

    Yousefi, Saleh; Keesstra, Saskia; Pourghasemi, Hamid Reza; Surian, Nicola; Mirzaee, Somayeh

    2017-01-01

    Fluvial dynamics in riverine borders can play an important role in political relationships between countries. Rivers move and evolve under the influence of natural processes and external drivers (e.g. land use change in river catchments). The Hirmand River is an important riverine border between

  16. Cross-border mobility of Iraqi refugees

    Directory of Open Access Journals (Sweden)

    Géraldine Chatelard

    2010-02-01

    Full Text Available Far more attention needs to be paid to the circulation of Iraqirefugees across the borders between Iraq and Syria or Jordan. Lackof analysis of this cross-border mobility will be to the detriment ofpolicy planning and the search for durable solutions.

  17. Green Belt Europe - borders separate, nature unites

    Science.gov (United States)

    Uwe Friedel

    2015-01-01

    During the period of the Cold War between 1945 and 1989, a "Green Belt" of valuable pristine landscapes developed along the border line between Eastern and Western Europe, the intensively fortified and guarded so called Iron Curtain. Due to the remoteness of the border areas, a high number of national parks and other large conservation areas can be found...

  18. The plaque removal effects of single rinsings and brushings.

    Science.gov (United States)

    Binney, A; Addy, M; Newcombe, R G

    1993-03-01

    Chemical plaque removal is one mechanism whereby an agent could improve oral hygiene and gingival health. As with toothpastes most agents, when delivered as rinses, would be considered adjunctive to mechanical tooth cleaning procedures. The aim of this study was to determine whether selected commercial rinses exhibited clinically significant plaque removal properties alone or when combined with toothbrushing with water or a toothpaste. A group of 12 volunteers took part in this single blind, randomized placebo-controlled, 12 cell cross-over study, employing 6 rinses. During each regimen subjects accumulated plaque from a zero baseline over 72 hours. Plaque removal was then measured by index and area after first a single rinse of product and second a subsequent brushing with water or toothpaste. Prebrushing rinsing removed less than 5% of the plaque with little difference between agents. No rinse was more adjunctive than water to postrinse brushings. Most statistically significant differences arose with the chlorhexidine rinse being apparently less effective. However, the possibility of a disclosing dye interaction cannot be discounted as explaining this anomalous result. This study could not support any claim of a direct prebrushing rinse benefit greater than that provided by water to mechanical plaque removal by any of the products tested.

  19. A novel music based tooth brushing system for blind children.

    Science.gov (United States)

    Shetty, V; Hegde, A M; Varghese, E; Shetty, V

    2013-01-01

    To assess the Oral Health Status (OHS) of visually impaired children in South India, to devise and implement a specially designed Oral Health Education (OHE) program for them and to assess its efficacy in improving their OHS. OHS of 98 institutionalized visually impaired children aged 6 to 14 years were evaluated at the start of the study (Pre-OHE level) using the Modified Gingival Index (MGI), the Turesky-Gilmore-Glickman modification of the Quigley Hein Plaque Index (MQHPI) and Streptococcus mutans colony count. Oral Health Education was imparted with the help of specially designed models and tooth-brushing taught with specially formulated music aided instructions in a song format. These parameters were re-evaluated after a period of reinforced (two weeks and one month) and non-reinforced (two months) tooth-brushing. Mean values of MGI and MQHPI showed a statistically very highly significant drop from the Pre-OHE level to the end of both the periods of reinforcement and non-reinforcement. There was a significant decrease in the S. mutans counts from the Pre-OHE levels to the period of non-reinforcement (p < 0.0005). The OHE program specially formulated for the visually impaired children was effective in improving their OHS significantly

  20. Dietary protease can alleviate negative effects of a coccidiosis infection on production performance in broiler chickens

    NARCIS (Netherlands)

    Peek, H.W.; Klis, van der J.D.; Vermeulen, B.; Landman, W.J.M.

    2009-01-01

    Two experiments were conducted to determine the effect of dietary protease on coccidiosis infection, production performance, the intestinal mucus layer thickness, and brush border enzyme activity using broilers challenged with Eimeria spp. laboratory isolates (Eimeria acervulina, E. maxima and E.

  1. Revitalising Borders: Memory, Mobility and Materiality in a Latvian-Russian Border Region

    Directory of Open Access Journals (Sweden)

    Aija Lulle

    2016-04-01

    Full Text Available In this paper I investigate how an international border is 'revitalised' in political discourses as opposed to lived experiences. Based on narratives I have collected from border dwellers on both sides of the current border between Latvia and Rus-sia and placing them into a broader context of current border debates, I analyse how geographical and social mobility is remembered from Soviet times and reworked in current contexts. I argue that while politically the border is revitalised through aban-doning and forgetting the Soviet past and through the idea of constant threats in the future, locally it is revitalised through giving a life to the abandoned: memories of 'vigorous times' in life-courses and material things. People who dwell at the border did not move themselves: the international border moved several times in one cen-tury leaving border dwellers' memories and significant places on the 'other' side. I focus on how these borders were crossed in the past, how they are (not crossed now, and the social meanings assigned to these circumstances. In the current con-text I follow diverse paths of reasoning that describe how the uneven flow of goods and people through the Latvian-Russian border shapes the power dynamic against which the people living in the border area used to reconstruct imaginaries of 'Soviet times' versus 'Europe' and 'vigorous times' versus decline.

  2. Description of fuel element brush assembly's fabrication for 105-K west

    International Nuclear Information System (INIS)

    Maassen, D.P.

    1997-01-01

    This report is a description of the process to redesign and fabricate, as well as, describe the features of the Fuel Element Brush Assembly used in the 105-K West Basin. This narrative description will identify problems that occurred during the redesigning and fabrication of the 105-K West Basin Fuel Element Brush Assembly and specifically address their solutions

  3. Synthesis and Direct Imaging of Ultrahigh Molecular Weight Cyclic Brush Polymers

    OpenAIRE

    Xia, Yang; Boydston, Andrew J.; Grubbs, Robert H.

    2011-01-01

    Convenient route to cyclic polymers: Ultrahigh molecular weight cyclic brush polymers were synthesized through ring-expansion metathesis polymerization of various macromonomers. Atomic force microscopy was used to visualize toroidal shapes and large opening pores, along with linear chains, which may result from high sensitivity of brush polymers to mechanical degradation.

  4. Preparation of plasmonic vesicles from amphiphilic gold nanocrystals grafted with polymer brushes

    OpenAIRE

    Song, Jibin; Huang, Peng; Chen, Xiaoyuan

    2016-01-01

    Gold nanovesicles contain multiple nanocrystals within a polymeric coating. The strong plasmonic coupling between adjacent nanoparticles in their vesicular shell makes ultrasensitive biosensing and bioimaging possible. In our laboratory, multifunctional plasmonic vesicles are assembled from amphiphilic gold nanocrystals (such as gold nanoparticles and gold nanorods) coated with mixed hydrophilic and hydrophobic polymer brushes or amphiphilic diblock co-polymer brushes. To fulfill the differen...

  5. Comparison of Saudi child versus parent-report of child tooth-brushing practices.

    Science.gov (United States)

    Salama, F; Abobakr, I; Al-Khodair, N; Al-Wakeel, M

    2016-01-01

    This cross-sectional study compared Saudi children's tooth-brushing practices as reported by children and parents and then matched the agreement of reports. A sample of 100 Saudi parents and their children of ages 8-12 years participated in this cross-sectional investigation. A self-administered structured questionnaire regarding the current tooth-brushing practice and habits at home was filled by the child. The same questionnaire was filled independently by parents. Mothers were more likely to teach children about tooth-brushing and fathers were minimally helping children during tooth-brushing. Mothers were the first to teach the children and approximately 33% of the children started brushing their teeth by age 5. Children and parents reported that children clean their teeth using a tooth-brush (73.74% and 76.77%), miswak (5.05% and 5.05%), or both (21.21% and 18.18%), respectively. There was some agreement between reported tooth-brushing practice of children and their parents. It is important to question both the child and parent regarding oral hygiene practice and compare their answers to get more broad knowledge about their practices. Approximately, one-third of the children started brushing their teeth by age 5, which differs from recommended oral hygiene practices.

  6. In Vitro Assessment of the Abrasion Resistance of Two Types of Artificial Teeth Submitted to Brushing.

    Science.gov (United States)

    Policastro, Vivian Barnabé; Giro, Gabriela; Leite, Andressa Rosa Perin; Mendoza-Marin, Danny Omar; Paleari, André Gustavo; Compagnoni, Marco Antonio; Pero, Ana Carolina

    2016-08-01

    To assess the effect of brushing with different solutions on the abrasion resistance of two types of acrylic resin teeth. Maxillary premolars from two types of acrylic teeth (Biotone and Biotone IPN) were divided into six groups (n = 12), according to the solution used during brushing: distilled water (control), coconut soap, or dentifrice. A mechanical brushing machine was used to simulate approximately 1 year of brushing (11,000 strokes). The weight loss (WL) of teeth was obtained from the difference between the initial (IW) and final weight (FW) of each specimen, and the mean of percentage of weight loss (PWL) was calculated for each group. Data were analyzed using the Kruskal-Wallis test, followed by Bonferroni's post-test comparison (α = 0.05). A statistically significant difference was found for the factor solution (p Brushing using dentifrice caused the highest values of weight loss (-0.50%), in comparison with the groups brushed with coconut soap (0.00%) or distilled water (0.00%). For both types of artificial teeth, brushing with dentifrice produced higher abrasion than brushing with coconut soap or water. © 2016 by the American College of Prosthodontists.

  7. Production rates for United States Forest Service brush disposal planning in the northern Rocky Mountains

    Science.gov (United States)

    Dan Loeffler; Stu Hoyt; Nathaniel Anderson

    2017-01-01

    Timber harvesting operations generate brush and other vegetative debris, which often has no marketable value. In many western U.S. forests, these materials represent a fire hazard and a potential threat to forest health and must be removed or burned for disposal. Currently, there is no established, consistent method to estimate brush disposal production rates in the U....

  8. Gallium-containing polymer brush film as efficient supported Lewis acid catalyst in a glass microreactor

    NARCIS (Netherlands)

    Munirathinam, Rajesh; Ricardi, Roberto; Egberink, Richard J.M.; Huskens, Jurriaan; Holtkamp, Michael; Wormeester, Herbert; Karst, U.; Verboom, Willem

    2013-01-01

    Polystyrene sulfonate polymer brushes, grown on the interior of the microchannels in a microreactor, have been used for the anchoring of gallium as a Lewis acid catalyst. Initially, gallium-containing polymer brushes were grown on a flat silicon oxide surface and were characterized by FTIR,

  9. A Low Cost Brush Deflection System for Bank Stabilization and Revegetation

    Science.gov (United States)

    Mary Elizabeth Meyer

    1989-01-01

    A series of brush deflectors were installed along an eroding, undercut streambank on Lindo Channel in Chico, California. Pieces of brush were wired to sets of metal fenceposts driven into the bank perpendicular to stream flow and at strategic points upstream. Dormant cuttings of riparian plants were added for revegetation and long-term bank protection. To date (two...

  10. "Hearing Loss" in QCM Measurement of Protein Adsorption to Protein Resistant Polymer Brush Layers.

    Science.gov (United States)

    Luan, Yafei; Li, Dan; Wei, Ting; Wang, Mengmeng; Tang, Zengchao; Brash, John L; Chen, Hong

    2017-04-04

    Accurate quantification of nonspecific protein adsorption on biomaterial surfaces is essential for evaluation of their antifouling properties. The quartz crystal microbalance (QCM) is an acoustic sensor widely used for the measurement of protein adsorption. However, although the QCM is highly sensitive, it does have performance limitations when working with surfaces modified with thick viscous layers. In the case of polymer brush surfaces, factors such as the thickness and viscosity of the brush may bring such limitations. In the present work, three types of antifouling molecules were used to explore the applicability of QCM for the evaluation of the protein resistance of hydrophilic polymer brush surfaces. Adsorption was also measured by surface plasmon resonance (SPR) as a reference. It was shown that the detection of adsorbed protein requires that protein be located within a critical distance from the QCM chip surface, determined by the viscosity of polymer brush. For larger proteins like fibrinogen, adsorption is expected to occur mainly "on top" of the polymer brush, and brush thickness determines whether protein is located in the "detectable zone". For smaller proteins like lysozyme, adsorption is expected to occur mainly at the chip surface and within the polymer brush layer and to be detectable by QCM. However, the quantity of adsorbed lysozyme may be underestimated when secondary adsorption also occurred. It is concluded that QCM data suggesting very low protein adsorption on polymer brush surfaces should take account of these considerations and should be treated generally with caution.

  11. Mycotoxins and the intestine

    Directory of Open Access Journals (Sweden)

    Leon Broom

    2015-12-01

    Full Text Available Fungal biochemical pathways can yield various compounds that are not considered to be necessary for their growth and are thus referred to as secondary metabolites. These compounds have been found to have wide ranging biological effects and include potent poisons (mycotoxins. Mycotoxins invariably contaminate crops and (thus animal feeds. The intestine is the key link between ingested mycotoxins and their detrimental effects on the animal. Effects on the intestine, or intestinal environment, and immune system have been reported with various mycotoxins. These effects are almost certainly occurring across species. Most, if not all, of the reported effects of mycotoxins are negative in terms of intestinal health, for example, decreased intestinal cell viability, reductions in short chain fatty acid (SCFA concentrations and elimination of beneficial bacteria, increased expression of genes involved in promoting inflammation and counteracting oxidative stress. This challenge to intestinal health will predispose the animal to intestinal (and systemic infections and impair efficient digestion and absorption of nutrients, with the associated effect on animal productivity.

  12. The effects of different multiple daily fractionation (MDF) on the small intestine

    International Nuclear Information System (INIS)

    Becciolini, A.; Balzi, M.; Cremonini, D.; Fabbrica, D.; Giache, V.

    1985-01-01

    The effects of 3 MDF were studied: 2Gyx3 x 2 with 8 h intervals (A), 2Gyx3 with 4 h intervals and after 16 h again 2Gyx3 (B), 3Gyx2 x 2 with 12 h intervals among fractions (C). The anaesthetized animals were exposed to a 60Co unit only on the abdomen. Brush border enzyme activity, lysosomal enzymes, protein content were studied. Qualitative and quantitative morphologic observations were carried on the proximal jejunum. Number of crypt and villus epithelial cells, mitotic and labelling indices, number of goblet cells and distribution of labelled cells in the crypt (after /sup 3/H Thymidine administration) were determined

  13. Buried, covalently attached RGD peptide motifs in poly(methacrylic acid) brush layers: the effect of brush structure on cell adhesion.

    Science.gov (United States)

    Navarro, Melba; Benetti, Edmondo M; Zapotoczny, Szczepan; Planell, Josep A; Vancso, G Julius

    2008-10-07

    Iniferter-mediated surface-initiated photopolymerization was used to graft poly(methacrylic acid) (PMAA) brush layers obtained from surface-attached iniferters in self-assembled monolayers to a gold surface. The tethered chains were subsequently functionalized with the cell-adhesive arginine-glycine-aspartic acid (RGD) motif. The modified brushes were extended by reinitiating the polymerization to obtain an additional layer of PMAA, thereby burying the peptide-functionalized segments inside the brush structure. Contact angle measurements and Fourier transform infrared (FTIR) spectroscopy were employed to characterize the wettability and the chemical properties of these platforms. Time of flight secondary ion mass spectroscopy (TOF-SIMS) measurements were performed to monitor the chemical composition of the polymer layer as a function of the distance to the gold surface and obtain information concerning the depth of the RGD motifs inside the brush structure. The brush thickness was evaluated as a function of the polymerization (i.e., UV-irradiation) time with atomic force microscopy (AFM) and ellipsometry. Cell adhesion tests employing human osteoblasts were performed on substrates with the RGD peptides exposed at the surface as well as covered by a PMAA top brush layer. Immunofluorescence studies demonstrated a variation of the cell morphology as a function of the position of the peptide units along the grafted chains.

  14. The border effects in Spain: an industry-level analysis

    OpenAIRE

    Llano Verduras, Carlos; Requena, Francisco

    2010-01-01

    A gravity-model approach is used to estimate the magnitude of the internal border (home bias) and external border (frontier) effects in Spain using industry-level trade flows. We find that the average border effects are about 30 and 10, respectively. Next we explore the variation in the industry-specific border effects. First, the border effects are larger in highly product differentiated industries. Second, the internal border effect is twice bigger for trade in intermediate g...

  15. Employment of Personnel at the Tucson Border Patrol Station

    Science.gov (United States)

    2017-06-09

    and Sells, Arizona. Tucson Station Border Patrol Agents (BPAs) drive to the border to perform their duties each day and night in different forms of...Station Border Patrol Agents (BPAs) drive to the border to perform their duties each day and night in different forms of personnel employment once...comprised of eight stations responsible for 262 linear miles of border from the New Mexico and Arizona border in the east to Yuma County, Arizona to

  16. Nitroxide polymer brushes prepared by surface-initiated ARGET ATRP and their selective oxidation performances

    Directory of Open Access Journals (Sweden)

    S. J. Liu

    2014-11-01

    Full Text Available Polymer brushes with 2,2,6,6-tetramethyl-4-piperidyl methacrylate (TMPM units, grafted on the cross-linked polystyrene (PS microspheres, were synthesized via surface-initiated ARGET (activators regenerated by electron transfer ATRP (atom transfer radical polymerization. They were further oxidized to yield nitroxide polymer brushes containing nitroxide radical units (TEMPO. The obtained polymer brushes were characterized by Fourier transform infrared spectroscopy (FT-IR, scanning electron microscopy (SEM, transmission electron microscopy (TEM, electron spin resonance (ESR and gel permeation chromatography (GPC. The catalytic properties of nitroxide polymer brushes for selective oxidation of benzyl alcohol were investigated. The results showed that the performances were good and the yield was up to 96%. Furthermore, the block brush had similar catalyst properties to non-supported TEMPO in terms of activity and selectivity. It could be recovered by centrifugation. The unity of high catalyst property and easy recovery was achieved.

  17. Intestinal solute carriers

    DEFF Research Database (Denmark)

    Steffansen, Bente; Nielsen, Carsten Uhd; Brodin, Birger

    2004-01-01

    A large amount of absorptive intestinal membrane transporters play an important part in absorption and distribution of several nutrients, drugs and prodrugs. The present paper gives a general overview on intestinal solute carriers as well as on trends and strategies for targeting drugs and...... membrane transporters in the small intestine in order to increase oral bioavailabilities of drug or prodrug, the major influence on in vivo pharmacokinetics is suggested to be dose-dependent increase in bioavailability as well as prolonged blood circulation due to large capacity facilitated absorption...

  18. Intestinal solute carriers

    DEFF Research Database (Denmark)

    Steffansen, Bente; Nielsen, Carsten Uhd; Brodin, Birger

    2004-01-01

    membrane transporters in the small intestine in order to increase oral bioavailabilities of drug or prodrug, the major influence on in vivo pharmacokinetics is suggested to be dose-dependent increase in bioavailability as well as prolonged blood circulation due to large capacity facilitated absorption......A large amount of absorptive intestinal membrane transporters play an important part in absorption and distribution of several nutrients, drugs and prodrugs. The present paper gives a general overview on intestinal solute carriers as well as on trends and strategies for targeting drugs and...

  19. Comparison between observed children's tooth brushing habits and those reported by mothers

    Directory of Open Access Journals (Sweden)

    Pordeus Isabela A

    2011-09-01

    Full Text Available Abstract Background Information bias can occur in epidemiological studies and compromise scientific outcomes, especially when evaluating information given by a patient regarding their own health. The oral habits of children reported by their mothers are commonly used to evaluate tooth brushing practices and to estimate fluoride intake by children. The aim of the present study was to compare observed tooth-brushing habits of young children using fluoridated toothpaste with those reported by mothers. Methods A sample of 201 mothers and their children (aged 24-48 months from Montes Claros, Brazil, took part in a cross-sectional study. At day-care centres, the mothers answered a self-administered questionnaire on their child's tooth-brushing habits. The structured questionnaire had six items with two to three possible answers. An appointment was then made with each mother/child pair at day-care centres. The participants were asked to demonstrate the tooth-brushing practice as usually performed at home. A trained examiner observed and documented the procedure. Observed tooth brushing and that reported by mothers were compared for overall agreement using Cohen's Kappa coefficient and the McNemar test. Results Cohen's Kappa values comparing mothers' reports and tooth brushing observed by the examiner ranged from poor-to-good (0.00-0.75. There were statistically significant differences between observed tooth brushing habits and those reported by mothers (p Conclusions In general, there was low agreement between observed tooth brushing and mothers' reports. Moreover, the different methods of estimation resulted in differences in the frequencies of tooth brushing habits, indicative of reporting bias. Data regarding children's tooth-brushing habits as reported by mothers should be considered with caution in epidemiological surveys on fluoridated dentifrice use and the risk of dental fluorosis.

  20. Plaque removal efficacy of two electric toothbrushes with different brush head designs.

    Science.gov (United States)

    Sharma, N C; Qaqish, J G; Galustians, H J; Goyal, C R; Cugini, M A; Thompson, M C; Warren, P R

    2005-06-01

    To compare the safety and plaque removal efficacy of two electric toothbrushes, one a rechargeable oscillating/pulsating toothbrush with a small round brush head (Oral-B ProfessionalCare 7000; PC 7000), the other a battery-operated toothbrush with a dual moving brush head (Crest SpinBrush Pro; SBP). The study had a randomised, examiner-blind, two-arm crossover design. All subjects received an oral prophylaxis and used both toothbrushes on alternating days for a two-week practice period. After abstaining from all oral hygiene procedures for 23-25 hours, subjects received an oral tissue examination and those with pre-brushing whole mouth mean plaque scores > or = 0.60 measured by the Rustogi et al. Modified Navy Plaque Index were randomly assigned to treatment sequence. Subjects brushed with their assigned toothbrush for 2 minutes using a commercially available dentifrice. Oral tissues were then re-examined and post-brushing plaque scores recorded. After a brief washout period, the above procedures were repeated with the alternate toothbrush. One examiner, blinded to the treatment sequence, performed all clinical measurements. A total of 70 subjects (24 males and 46 females) were enrolled and completed the study. Each toothbrush was found to be safe and significantly reduced plaque levels after a single brushing. The PC 7000 was significantly more effective in plaque removal than the SBP at all tooth areas, reducing whole mouth plaque by 61% versus 58% and plaque from approximal surfaces by 69% versus 65%, respectively. The action of the oscillating/pulsating toothbrush with a small round brush head, Oral-B ProfessionalCare 7000, is more effective in plaque removal than the battery-operated Crest SpinBrush Pro toothbrush with a larger dual moving brush head.

  1. Effects of whitening dentifrice on yttria-stabilized tetragonal zirconia polycrystal surfaces after simulating brushing.

    Science.gov (United States)

    Pinelli, Lígia Antunes Pereira; Gimenes Olbera, Amanda Caroline; Candido, Lucas Miguel; Miotto, Larissa Natiele; Antonio, Selma Gutierrez; Fais, Laiza Maria Grassi

    2017-01-01

    The changes that occur after brushing yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) are unknown. These changes may favor the retention of microorganisms and chemisorption of water, impairing its longevity. The purpose of this in vitro study was to evaluate the effects of a whitening dentifrice on Y-TZP surfaces after simulating 10 years of brushing. Seventy-two bar-shaped specimens (20×4×1.2 mm) were divided into 4 groups: storage in distilled water (SW, control), brushing with distilled water (BW), brushing with dentifrice (BD), and brushing with whitening dentifrice (BWD). Brushing was conducted using a linear brushing machine (878400 cycles, 0.98 N, soft toothbrush). The mean roughness (Ra) was analyzed with a profilometer and the superficial topography with scanning electron microscopy (SEM) at baseline and after treatment. Crystalline phases were characterized using x-ray diffraction. Baseline and posttreatment Ra were analyzed using the 1-way ANOVA and Tukey HSD multiple comparison test; the paired t test was used for intragroup comparison (all α=.05). The Ra (μm) means (before/after treatment) were SW 0.28/0.28; BW 0.32/0.31; BD 0.28/0.36; BWD 0.30/0.20. No statistically significant difference was found for Ra at baseline (P=.108) than for posttreatment results (P<.001); the BD group had higher Ra values when compared with baseline (P=.019); the BWD group had the lowest values (P<.001). The BD surfaces showed pronounced scratches and detachment of the surface, while BWD showed smoother surfaces; similar crystallographic results among groups were observed. Brushing Y-TZP with conventional dentifrice increased roughness, while brushing with whitening dentifrice reduced roughness. Neither dentifrice changed the crystallographic phases after brushing. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  2. Experience of racism and tooth brushing among pregnant Aboriginal Australians: exploring psychosocial mediators.

    Science.gov (United States)

    Ben, J; Jamieson, L M; Priest, N; Parker, E J; Roberts-Thomson, K F; Lawrence, H P; Broughton, J; Paradies, Y

    2014-09-01

    Despite burgeoning evidence regarding the pathways by which experiences of racism influence health outcomes, little attention has been paid to the relationship between racism and oral health-related behaviours in particular. We hypothesised that self-reported racism was associated with tooth brushing, and that this association was mediated by perceived stress and sense of control and moderated by social support. Data from 365 pregnant Aboriginal Australian women were used to evaluate tooth brushing behaviour, sociodemographic factors, psychosocial factors, general health, risk behaviours and racism exposure. Bivariate associations were explored and hierarchical logistic regression models estimated odds ratios (OR) and 95% confidence intervals (CI) for tooth brushing. Perceived stress and sense of control were examined as mediators of the association between self-reported racism and tooth brushing using binary mediation with bootstrapping. High levels of self-reported racism persisted as a risk indicator for tooth brushing (OR 0.51, 95%CI 0.27,0.98) after controlling for significant covariates. Perceived stress mediated the relationship between self-reported racism and tooth brushing: the direct effect of racism on tooth brushing was attenuated, and the indirect effect on tooth brushing was significant (beta coefficient -0.09; bias-corrected 95%CI -0.166,-0.028; 48.1% of effect mediated). Sense of control was insignificant as a mediator of the relationship between racism and tooth brushing. High levels of self-reported racism were associated with non-optimal tooth brushing behaviours, and perceived stress mediated this association among this sample of pregnant Aboriginal women.. Limitations and implications are discussed.

  3. Effectiveness of Chewable Tooth Brush in Children-A Prospective Clinical Study.

    Science.gov (United States)

    Govindaraju, Lavanya; Gurunathan, Deepa

    2017-03-01

    Dental plaque is one of the aetiological factors in causation of dental caries. Effective removal of plaque can reduce the incidence of caries. Various agents for removing plaque has been introduced, of which, chewable brush is a recent advance. There is limited evidence assessing the effectiveness of using chewable brush in children. The aim of this study was to evaluate the effectiveness of chewable brush in relation to efficiency in plaque removal and reduction in S.mutans counts in saliva. Ten children of six-nine years with their first molars erupted were included in the study and the children were supervised for their normal brushing for 7 days. The baseline Oral Hygiene Index-Simplified (OHI-S), Plaque Index (PI) and Decay, Missing Filled Tooth Index (DMFT-I) were noted and the saliva sample was collected from the children. The sample was sent for microbiological examination of S.mutans count and the pH of the saliva was also determined. The children were advised to brush their teeth twice daily for seven days using chewable brush. On the seventh day, the indices were noted again and the saliva sample was collected and sent for microbiological examination. Statistical analysis was done using paired t-test to compare the pre and post-brushing index scores, S. mutans count and salivary pH. There was a significant reduction in the debris index (pbrushing with chewable brush. However, the calculus index remained unchanged (p=0.168). Chewable brush can be used as an effective alternative to manual brushing in children.

  4. Languaging the Borders of Europe

    Directory of Open Access Journals (Sweden)

    Olivier Kramsch

    2015-11-01

    Full Text Available Emerging from a discomfort with the blind spots encountered within and across theorizations of language and space in the field of human geography, in this article, we argue for “making space” for conceptualizations that speak from and through the everyday territories of migrants in Europe today. Inspired by a range of writers thinking postcolonially and multi/trans-lingually, the authors draw on their own embodied migrant experience to argue for re-envisioning Europe’s borders through multiple languaging practices. “Languaging”, in this view, takes linguistic practices in a migrant context as an inherently prosthetic activity, whereby any dominant, national host language is inevitably subject to the subterranean rumblings of all the languages a migrant brings with her on her global journeys. Conceived as being saturated with prosthetic “absence(s”, migrant languaging practices rework cultural geography’s bounded, inward-looking, and security-fixated understanding of the language/territory nexus, the better to open a vital space for re-envisioning language’s everyday territories as sites for translational solidarity and becoming.

  5. Borders, boundaries and desirable wishes

    Directory of Open Access Journals (Sweden)

    Luca Pinciaroli

    2015-05-01

    Full Text Available “Borders, boundaries and desirable wishes” is the title of the residential workshop offered to a group of young adults (aged 18-25 of the Centro di Salute Mentale (Mental Health Center of the DSM Basaglia of ASL TO2 in Turin. The idea of the workshop, the definition of the objectives and the topics, which are clearly expressed in the title, come from the work of the team dedicated to group psychotherapies, which has been offering group psychodrama sessions to young adults of this age since 2008. In the delicate move to the adult age, these young adults are lost and stuck in static realities where it is not possible to open up to the dimension of desire nor to the transforming encounter with the Other, since they didn’t have the experience of boundaries and lack. These two elements are necessary to acquire the ability to make projects for oneself. During the workshop the following instruments were used: group, psychodrama and art therapy. The group, as a paternal function, ensured the presence of safe boundaries enabling individuals to experiment; psychodrama and art therapy enabled the bodies to experience encounters and transformations, using doing as a metaphor for the movement against the inhibition of doing and as a way to show oneself to the Other and be able to see the Other. 

  6. Semantic Borders and Incomplete Understanding.

    Science.gov (United States)

    Silva-Filho, Waldomiro J; Dazzani, Maria Virgínia

    2016-03-01

    In this article, we explore a fundamental issue of Cultural Psychology, that is our "capacity to make meaning", by investigating a thesis from contemporary philosophical semantics, namely, that there is a decisive relationship between language and rationality. Many philosophers think that for a person to be described as a rational agent he must understand the semantic content and meaning of the words he uses to express his intentional mental states, e.g., his beliefs and thoughts. Our argument seeks to investigate the thesis developed by Tyler Burge, according to which our mastery or understanding of the semantic content of the terms which form our beliefs and thoughts is an "incomplete understanding". To do this, we discuss, on the one hand, the general lines of anti-individualism or semantic externalism and, on the other, criticisms of the Burgean notion of incomplete understanding - one radical and the other moderate. We defend our understanding that the content of our beliefs must be described in the light of the limits and natural contingencies of our cognitive capacities and the normative nature of our rationality. At heart, anti-individualism leads us to think about the fact that we are social creatures, living in contingent situations, with important, but limited, cognitive capacities, and that we receive the main, and most important, portion of our knowledge simply from what others tell us. Finally, we conclude that this discussion may contribute to the current debate about the notion of borders.

  7. Dyck Words, Lattice Paths, and Abelian Borders

    OpenAIRE

    Blanchet-Sadri, F.; Chen, Kun; Hawes, Kenneth

    2017-01-01

    We use results on Dyck words and lattice paths to derive a formula for the exact number of binary words of a given length with a given minimal abelian border length, tightening a bound on that number from Christodoulakis et al. (Discrete Applied Mathematics, 2014). We also extend to any number of distinct abelian borders a result of Rampersad et al. (Developments in Language Theory, 2013) on the exact number of binary words of a given length with no abelian borders. Furthermore, we generalize...

  8. The effectivity of toothpick tooth brushing method on plaque control

    Directory of Open Access Journals (Sweden)

    Chiquita Prahasanti

    2011-06-01

    Full Text Available Background: Periodontal diseases are associated with bacteria species which present in biofilms that colonize on dental surfaces. Several tooth brushing methods had been known and proved to be effective in maintaining oral hygiene. Among them, tooth pick technique was a relatively new method and its superiority in removing interproximal plaque was better than other methods. Purpose: The purpose of this study was to examine the effectivity of toothpick tooth brushing method to conventional method on periodontal health. Methods: This research was designed as an analytical observational study. Thirty samples selected from five hundred and twelve males Indonesian Air-force members in Malang, aged 18–40 yrs, with periodontal pockets (≤ 5 mm in upper or lower teeth, without crowding, gingival index minimal > 1 (moderate gingivitis, OHI-S score minimal ≥ 1.3 (moderate, without systemic diseases, do not undergone medical therapy/drug prescriptions, without using mouth rinse during study, and without prosthesis. There were thirty samples in this research and devided to two groups, fifteen samples easch. The groups were toothpick tooth brusing method and conventional method (control group. In this study oral hygiene index simplified (OHI-S, gingival index (GI, bleeding on probing (BOP and pocket depth were examined. Results: There were significant differences (p = .001 in OHI-S, GI, BOP, and PD before and after conducting each toothbrushing method, as well as differences between means (quarrel means, that were p = .003; p = .001; p = .001 and p = .001 consecutively. Conclusion: Toothpick brushing method was more effective in plaque control compared to conventional method.Latar belakang: Penyakit periodontal berhubungan dengan bakteri yang berkoloni dalam biofilm yang terdapat di permukaan gigi. Saat ini telah dikenal berbagai macam metode menyikat gigi tetapi masih belum ada penelitian tentang efek metode tersebut terhadap OHI-S. Penelitian in ingin

  9. Everybody Brush! Consumer Satisfaction with a Tooth Decay Prevention Program.

    Science.gov (United States)

    Cunha-Cruz, Joana; Huebner, Colleen E; Ludwig, Sharity; Dysert, Jeanne; Mitchell, Melissa; Allen, Gary; Shirtcliff, R Mike; Scott, JoAnna M; Milgrom, Peter

    2017-01-01

    Twice-daily caregiver-supervised toothbrushing with fluoridated toothpaste is an effective and widely recommended strategy to prevent tooth decay in children. Qualitative research suggests that low-income caregivers know the recommendation but would benefit from toothbrushing supplies and advice about how to introduce this health behavior especially as the child becomes older and asserts autonomy to do it "myself." Our objective is to assess consumer satisfaction with the evidence-based theory-informed campaign and usefulness of materials that were home delivered. The focus of the evaluation was families with children tooth decay among low-income children. Caregivers were highly satisfied with the Everybody Brush! program and toothbrushing supplies were considered the most useful, followed by printed messages. Voice telephone messages were rated least useful. Further evaluation of the impact of the program on toothbrushing behavior and dental-care utilization is underway.

  10. Cross-border shopping and tourism destination marketing

    DEFF Research Database (Denmark)

    Makkonen, Teemu

    2016-01-01

    This article addresses the economic impact that cross-border shopping has on the local tourism industry and the ways that cross-border shopping is taken advantage of in tourism destination marketing. Southern Jutland–situated in Denmark just north of the German border, where border shops situated......-border shopping into tourism destination marketing strategies. The results have wider relevance for other border regions.......This article addresses the economic impact that cross-border shopping has on the local tourism industry and the ways that cross-border shopping is taken advantage of in tourism destination marketing. Southern Jutland–situated in Denmark just north of the German border, where border shops situated...... just south of the same border enable Danes to capitalize on the lower value added tax levels in Germany–is utilized as an illustrative case example. The data was collected by analysing the relevant tourism destination marketing material and via interviews with local destination marketing organizations...

  11. Borders in Europe: From history to everyday life

    Directory of Open Access Journals (Sweden)

    Narcís Bassols

    2017-01-01

    Full Text Available

    This article reflects on European borders and their everyday dynamics from a cross-border perspective. The article begins with a discussion of recent events that question current border policies in the European Union, reviews the literature on borders and border territories, and finally moves on to a discussion of the everyday effects of cross-border practices on the inhabitants of border spaces. Occasional reference is made to borders in the Americas to complete the picture of this topic. Although the issue of security is indeed relevant, we focus on the economic and social dimensions of cooperation. Three aspects are essential for border residents who attempt to use the advantages of the territories for their global nature: work, shopping, and place of residence. In conclusion, there has been a tendency toward the softening of borders and greater integration of border zones in the European Union.

  12. Borders as barriers to tourism: tourists experiences at the Beitbridge Border Post (Zimbabwean side

    Directory of Open Access Journals (Sweden)

    Getrude Kwanisai

    2014-01-01

    Full Text Available International borders greatly influence tourism development. In 2012 and 2013, a decline in tourists to Zimbabwe from South Africa was partially attributed to tourist border facilitation issues. It is against this background that this study sought to establish the nature of challenges faced by tourists when using the Beitbridge border post (Zimbabwean side. Questionnaire responses were thematically analysed and the study concluded that border administrative management related issues are a major barrier to tourism. Key among the study's recommendations is that the depressed tourists' border experiences obtaining at Beitbridge border post among other constraints have to be addressed as a matter of urgency. This will enhance Zimbabwe's accessibility, tourist satisfaction and the image of the country as a destination. The paper further identifies several destination managerial implications and future research priorities.

  13. Elastic and hegemonic borders and discourse theory: Mexico’s southern border

    Directory of Open Access Journals (Sweden)

    Jorge Marengo Camacho

    2015-12-01

    Full Text Available Discourse theory is useful for understanding the creation of borders, whether material or imaginary. This paper addresses three situations on Mexico’s southern border between 2000 and 2015 in which elements of discourse theory may be applied. The outcomes were the following: 1 correlations may be made between the elements of the discourse moving from the northern to the southern border, but not in the opposite direction; 2 the process of securitising the discourse about migrants is continuous, and new securitising elements are regularly added; 3 an “elastic borders” phenomenon exists, where borders extend or retract, thereby creating new border regions; and 4 discourses around the southern border are constructed with more pejorative elements than the northern, despite the fact that crime rates are higher in the north.

  14. Externalization and Border-induced Displacement

    DEFF Research Database (Denmark)

    Lemberg-Pedersen, Martin

    This multidisciplinary Ph.D. dissertation engages with the timely and much debated topic of European border control. The first two chapters discuss several moral arguments claiming that border control facilitates solidarity and autonomy. These are assessed with reference to central debates...... in political philosophy concerning coercion, entry/exit, protection elsewhere and self-determination, and against the backdrop of empirical cases, such as the EU Commission’s UNHCR-donations, the Dublin II Regulation and the export of migrant camps to North Africa. In the third article the governance of asylum...... and the international banking sector all have overlapping interests in privatized border control. Chapter five identifies the multiple flows, technological, personnel, funds and data, maintaining Europe’s border infrastructure, As migrants are circulated between detention camps and countries, dumped in deserts...

  15. Abuses at Europe’s borders

    Directory of Open Access Journals (Sweden)

    Duncan Breen

    2016-01-01

    Full Text Available Refugees and migrants have been regularly subjected to widespread rights violations by officials at some European borders. The EU needs to allow more legal avenues for people seeking protection to reach Europe safely.

  16. Conservative Libertarianism and the Ethics of Borders

    Directory of Open Access Journals (Sweden)

    Enrique Camacho Beltran

    2015-06-01

    Full Text Available Many conservatives endorse a defence of closed borders grounded in basic liberal rights such as the basic right of association. Some conservatives also endorse libertarian principles of legitimacy. It is not clear though that this sort of defence of closed borders is somehow coherent with these libertarian ideals. I argue that conservative libertarians of this kind must reject this defence of closed borders because either it collapses into a form of statism incoherent with libertarian principles of legitimacy, or into an ideal precept without appeal regarding reality in the here and now that could only be applied to changing the very nature of the societies we know. As a result, at least conservative libertarians need to find a different source of justification for closed borders.

  17. The optimal sequence for bronchial brushing and forceps biopsy in lung cancer diagnosis: a random control study.

    Science.gov (United States)

    Hou, Gang; Miao, Yuan; Hu, Xue-Jun; Wang, Wei; Wang, Qiu-Yue; Wu, Guang-Ping; Wang, En-Hua; Kang, Jian

    2016-03-01

    Optimizing basic techniques in diagnostic bronchoscopy is important for improving medical services in developing countries. In this study, the optimal sequence of bronchial brushing relative to bronchial biopsy for lung cancer diagnosis was evaluated. A total of 420 patients with visible endobronchial tumors were prospectively and randomly enrolled in two groups: a pre-biopsy brushing group, receiving two brushings before biopsy; two brushings which performed afterwards; were set as self-control and compared with the pre-biopsy brushings as the intra-group comparison; and a post-biopsy brushing group, only receiving two brushings after biopsy, which were compared with the pre-biopsy brushings as the inter-group comparison. Diagnostic yield of brushing was compared before and after biopsy, and as well as for different tumor pathologies and bronchoscopic morphologies. The occurrence of treated bleeding which defined as bleeding needed further intervention with argon plasma coagulation and/or anti-coagulation drugs in two groups was also compared. Only patients with a definitive cytological or histological diagnosis of lung cancer based on bronchoscopy or other confirmatory techniques were included. Patients were excluded if they had submucosal lesions, extrinsic compressions, pulmonary metastasis of extrapulmonary malignancies or uncommon non-small cell lung carcinoma (NSCLC). A total of 362 patients who met the inclusion criteria were analyzed. Diagnostic yield for pre-biopsy brushing (49.2%, 88/179) was significantly higher than for post-biopsy brushing within the same pre-biopsy brushing group (31.8%, 57/179) (P=0.007) as the intra-group comparison, and significantly higher than for post-biopsy brushing in the post group (30.6%, 56/183) (Pcancer. In cases of endobronchial exophytic tumors, pre-biopsy brushing appears to be superior to post-biopsy brushing.

  18. Border Security: A Conceptual Model of Complexity

    Science.gov (United States)

    2013-12-01

    to aid stranded drivers with no food, water, or toilets.5 Computer manufacturers in Taiwan, Singapore, and South Korea could not ship their 3...border inspections. Washington State, for example, experienced a 50% drop in tourism and lost over $100 million in local revenue because of the...in large part because of what is known as “The Amistad Case.” The Spanish cargo ship La Amistad ran aground on the coastal border of New York

  19. Territorial borders, toleration and the English school.

    OpenAIRE

    Williams, J.

    2002-01-01

    This article offers an assessment of the ethical status of territorial borders, arguing for a partial defence of their role in international relations. Utilising the English School as one way such a defence has been developed, it assesses pluralist and solidarist arguments, suggesting both are flawed. The article develops a notion of territorial borders as contributing to the value of tolerating difference in international relations, and that this is an ethically desirable thing to do. In doi...

  20. The Effects of Tooth Brushing on Whole Salivary Flow Rate in Older Adults

    Directory of Open Access Journals (Sweden)

    R. H. Affoo

    2018-01-01

    Full Text Available Objectives. (1 To determine whether manual (MTB, or electric, tooth brushing (ETB modulates whole salivary flow rate in older adults who are free of systemic disease. (2 To determine the duration of the brushing-related modulation of salivary flow rate. (3 To compare salivary flow rate modulation associated with MTB and ETB. Method. Twenty-one adults aged 60 years and older participated in two experimental sessions during which they used a manual, or electric, toothbrush to brush their teeth, tongue, and palate. Whole salivary flow rates were determined using the draining method before, during, and after brushing. Differences in salivary flow rates across time periods, and between conditions, were examined using paired samples t-tests applying a Holm-Bonferroni sequential procedure (pcorr<0.0045. The relationship between tooth brushing and age with respect to maximum salivary flow rate increase was examined using Pearson’s correlation coefficient (p<0.05. Results/Conclusion. Whole salivary flow rates increased during, and for up to 5 minutes following, tooth brushing in adults aged 60 years and older who were free of systemic disease. The salivary effects of MTB and ETB were not significantly different. A moderate, positive correlation was observed between tooth-brushing-related maximum salivary flow rate increase and age.

  1. Control of Cell Attachment and Spreading on Poly(acrylamide) Brushes with Varied Grafting Density.

    Science.gov (United States)

    Lilge, Inga; Schönherr, Holger

    2016-01-26

    To achieve spatial control of fibroblast cell attachment and spreading on a biocompatible polymer coating, the effect of poly(acrylamide) (PAAm) brushes with varied grafting density was investigated. The synthesis of the brushes was performed by surface-initiated atom transfer radical polymerization (SI-ATRP). Gold substrates were modified with binary self-assembled monolayers (SAMs) of an initiator and 16-mercaptohexadecanoic acid (MHDA) as an "inert" thiol to initiate the ATRP of AAm. By using different mixtures for the binary SAMs, a series of polymer brushes with varied grafting densities were prepared. The fractional coverage of surface bound initiator was determined by grazing incidence Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and contact angle measurements. A linear relationship between the Br/S ratio determined by XPS and ToF-SIMS versus the fraction of initiator on the surface determined by water contact angle measurements was observed. The varied initiation concentration on the gold substrates yielded PAAm brushes with different thicknesses, indicating a transition from mushroom to brush regimes with increasing grafting density. Thereby we achieved exquisite control of the degree of cell adhesion. Cell attachment experiments with NIH 3T3 fibroblast cells revealed cell spreading on PAAm brushes with low grafting densities (initiator fractional coverage <0.2) as well as a complete passivation by polymer brushes with higher grafting densities.

  2. Nanocomposites Consisting of Nanoparticles with Multidentate PS Brushes Mixed with PS Matrices

    Science.gov (United States)

    Lee, Hyemin; Wooh, Sanghyuk; Lim, Jaehoon; Zorn, Matthias; Zentel, Rudolf; Char, Kookheon

    2011-03-01

    In order to prevent massive phase separation of nanoparticles (NP) in a polymer matrix, the relevant hybridization of NPs with polymer matrices has proven to be an effective method for the high performance of nanocomposites in applications. The surface of inorganic (gold or QD) NPs of various size was modified with polystyrene (PS) polymer brushes, poly(styrene)-block-poly(cysteamine methyl disulfide), by the ligand exchange procedure. The disulfide groups in the PS brushes act as anchoring blocks for NPs. Different PS brushes were prepared with different total molecular weights and mole fractions of disulfide moieties. Compared with NPs dispersed in PS without disulfide anchoring groups, NPs anchored with PS brushes through disulfide groups were uniformly distributed within PS matrices. The dispersion of NPs within a polymer matrix was found to be influenced by the total molecular weight of PS brushes as well as the number of anchoring disulfide groups. Furthermore, the effect of the ratio between relative size of NP and the radius of gyration of a polymer brush as well as the grafting density of PS brushes anchored onto NPs on the NP distribution within a polymer matrix is discussed.

  3. Tooth brushing skills for the children aged 3-11 years

    Directory of Open Access Journals (Sweden)

    Das U

    2009-06-01

    Full Text Available Objectives: The objective of this study was to evaluate tooth brushing management and ability of children in relation to age and gender. Materials and Methods: The study population consisted of 45 children, who attended Department of Pedodontics and Preventive Dentistry at V.S Dental College and Hospital Bangalore. Children were divided into three groups according to age: Group I: 3-5 years, Group II: 6-8 years, and Group III: 9-11 years. Each child selected his/her favorite toothbrush and brushed his/her teeth under supervision of one instructor. The grip type during tooth brushing was recorded on a videotape and duration of tooth brushing also was noted. The data were analyzed in relation to the age and gender using the chi-square test. ANOVA was used to find if there is any significant difference between the mean brushing times in the different groups. Results: The results of statistical analysis showed that in all cases P> 0.05 for grip preferences and P < 0.001 between age groups 3-5 years and 9-11 years with respect to the mean brushing time. Conclusion: The required manual dexterity for tooth brushing was present in younger age groups.

  4. Facilitators and barriers to twice daily tooth brushing among children with special health care needs.

    Science.gov (United States)

    Campanaro, Maria; Huebner, Colleen E; Davis, Beth Ellen

    2014-01-01

    The oral hygiene routines of preschool-age children with special health care needs (CSHCN) were examined to identify caregiver behaviors and beliefs associated with twice daily tooth brushing. Ninety caregivers of CSHCN, ages 23 to 62 months, were interviewed to determine supports or barriers to tooth brushing. Ninety-eight percent of caregivers had begun brushing their child's teeth and half reported brushing twice daily. Caregivers' brushing skills and the availability of child-friendly supplies were associated with twice daily versus less frequent brushing (p = .02). This study adds insight into the challenges of establishing daily oral health care for children who must rely on others for their care. The facilitators and barriers to tooth brushing by caregivers of CSHCN are similar to those noted previously among parents of typically developing children. Efforts to improve all caregivers' oral hygiene skills are needed. For caregivers of CSHCN, oral health teaching opportunities may exist among professionals who provide ongoing medical care, special services and therapies. © 2014 Special Care Dentistry Association and Wiley Periodicals, Inc.

  5. Children's toothbrushing frequency: the influence of parents' rationale for brushing, habits and family routines.

    Science.gov (United States)

    Trubey, Rob J; Moore, Simon C; Chestnutt, Ivor G

    2015-01-01

    To assess the relationship between parental and family factors and children's toothbrushing frequency at different times of day. A cross-sectional questionnaire survey of predominantly low-socio-economic status parents of children aged 3-6 years (n = 296) in South Wales, UK. Data were collected on the child's weekly toothbrushing frequency (morning and evening), the parents' rationale for brushing their child's teeth in the morning and evening, the strength of a parent's habit for brushing a child's teeth in the morning and evening, and the extent to which the family's daily routines were stable from day to day. Socio-demographic details were also collected. Reported weekly brushing frequency was significantly (p brushing in the evening. The extent to which brushing a child's teeth was 'habitual' was significantly (p brushing their children's teeth can vary at both an individual level and at different times of day. Understanding these variations is important in designing interventions to improve brushing frequency for at-risk children. The results also demonstrate habituation as being an important factor in understanding toothbrushing frequency. Further research is required to understand the mechanisms involved in habit formation and maintenance with children's oral hygiene behaviour.

  6. Experience of maintaining tooth brushing for children born with a cleft lip and/or palate.

    Science.gov (United States)

    Lin, Yin-Ling; Davies, Karen; Callery, Peter

    2017-08-24

    Children with a Cleft Lip and/or Palate (CL/P) have been reported to have poorer oral health than those without the condition. The consequences for these children can be particularly problematic due to implications for future treatments. Tooth brushing is an important behaviour contributing to children's oral health, but is under researched in the CL/P population. The aim of the study is to explore the experience of maintaining tooth brushing among children in the United Kingdom (UK) with a CL/P and their parents. Semi-structured interviews were carried out with twenty-two parents and sixteen children with a CL/P (5-11 years), recruited at a cleft centre in the UK. Thematic analysis was used for data analysis. Three key themes were drawn from the qualitative data: first, parents of children with a CL/P generally had strong motivation to look after their children's teeth but children's motivation was inconsistent. Second, parents were primary enablers of children's tooth brushing behaviour, often employing approaches adapted to their child's characteristics to encourage tooth brushing. Third, a range of obstacles were encountered by parents and children in maintaining regular tooth brushing behaviours. They reported obstacles such as issues related to CL/P, 'forgetting' and childhood illness. The paper suggests that parents of children with a CL/P need support to enact their intention to maintain regular tooth brushing and prioritise tooth brushing within the context of demanding and dynamic family life.

  7. Relationship of tooth brushing to metabolic syndrome in middle-aged adults.

    Science.gov (United States)

    Tanaka, Akihiko; Takeuchi, Kenji; Furuta, Michiko; Takeshita, Toru; Suma, Shino; Shinagawa, Takashi; Shimazaki, Yoshihiro; Yamashita, Yoshihisa

    2018-02-08

    To examine the effect of tooth brushing on the development of metabolic syndrome, including assessment of periodontal status, in middle-aged adults. This 5-year follow-up retrospective study was performed in 3722 participants (2897 males and 825 females) aged 35-64 years who underwent both medical check-ups and dental examinations. Metabolic components included obesity, elevated triglycerides, blood pressure, fasting glucose, and reduced high-density lipoprotein. Tooth brushing frequency was assessed using a questionnaire. Periodontal disease was defined as having at least one site with a pocket depth of ≥4 mm. Logistic regression analysis was performed to evaluate the relationship between tooth brushing frequency at the baseline examination and the development of metabolic syndrome (≥3 components). During follow-up, 11.1% of participants developed metabolic syndrome. After adjusting for potential confounders including periodontal disease, participants with more frequent daily tooth brushing tended to have significantly lower odds of developing metabolic syndrome (P for trend = 0.01). The risk of development of metabolic syndrome was significantly lower in participants brushing teeth ≥3 times/day than in those brushing teeth ≤1 time/day (odds ratio = 0.64, 95% confidence interval: 0.45-0.92). Frequent daily tooth brushing was associated with lower risk of development of metabolic syndrome. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. Polyelectrolyte Brush-Grafted Polydopamine-Based Catalysts with Enhanced Catalytic Activity and Stability.

    Science.gov (United States)

    Kaang, Byung Kwon; Han, Nara; Lee, Ha-Jin; Choi, Won San

    2018-01-10

    Three types of surface treatments, namely, polyethyleneimine (PEI) coating, short PEI (S-PEI) grafting, and long PEI (L-PEI) grafting, were performed on polydopamine (Pdop)-based catalysts to enhance their catalytic activity and stability. Brush-grafted catalysts were prepared by the stepwise synthesis of Au and short (or long) PEI brushes on Pdop particles (PdopP/Au/S- or L-PEI grafting). PEI-coated Pdop-based catalysts (PdopP/Au/PEI coating) were also prepared as non-brush-grafted catalysts. Among the surface-treated PdopP/Au catalysts, the brush-grafted catalysts (S-PEI and L-PEI grafting) exhibited excellent and stable catalytic performance because the brush grafting enabled the protection of the catalysts against harsh conditions, effective transfer of reactants to the catalysts, and confinement of reactants around the catalysts. The brush-grafted catalysts could also more effectively decompose larger dyes than the non-brush-grafted catalysts. The process-to-effectiveness of PEI coating is the best because the release of Pdop from PdopP/Au was moderately inhibited by the presence of only one layer of PEI coating on the PdopP/Au. Thus, this approach could be an alternative method to enhance the stability of PdopP/Au catalysts.

  9. Sequential nucleophilic substitutions permit orthogonal click functionalization of multicomponent PEG brushes.

    Science.gov (United States)

    Sha, Jin; Lippmann, Ethan S; McNulty, Jason; Ma, Yulu; Ashton, Randolph S

    2013-09-09

    Multicomponent poly(ethylene glycol) (PEG) brushes (i.e., ≥ 2 adjacent PEG brushes) can be used to engineer culture substrates with microscale, nonfouling regions decorated with covalently immobilized ligands that mediate biospecific interactions. However, synthesizing such brushes with orthogonal immobilization chemistries to permit differential biofunctionalization is nontrivial and often requires synthesis of PEG-co-polymers. To simplify synthesis and enhance the versatility of such substrates, we developed a protocol for generating orthogonal click-functionalized multicomponent PEG brushes using sequential nucleophilic substitutions by sodium azide, ethanolamine, and propargylamine. The novel application of propargylamine-mediated substitution functionalizes PEG brushes with acetylene groups, and for the first time, ethanolamine-mediated substitution is shown to be sufficient for passivating the "living" polymer chain ends between brush synthesis steps. Thus, our multicomponent PEG brushes present dual orthogonal chemistries (i.e., azido and acetylene groups) for ligand immobilization via versatile copper-free click reactions, which are useful for in situ surface modifications during cell culture.

  10. Comparison of the tooth brushing habits of primary school age children and their parents.

    Science.gov (United States)

    Ozbek, Ceren Damla; Eser, Didem; Bektas-Kayhan, Kivanc; Unur, Meral

    2015-01-01

    As they grow, children develop their attitude and behavior related to tooth brushing by taking their parents' oral-dental health behavior as an example. The purpose of this study was to assess whether there was a similarity in tooth brushing between primary school-age children and their parents presenting to the Department of Oral, Dental and Jaw Diseases and Surgery and the Department of Pedodontics, School of Dental Medicine, Istanbul University. The study included 126 children and their parents, as totally 252 subjects. The data on oral hygiene of the subjects were obtained using a questionnaire form including questions on the qualitative-quantitative tooth brushing habits of the children and their parents and the socio-demographic characteristics of their families. In most of the cases, there was a similarity between children and their parents in terms of the frequency of dentist visits, the therapy they underwent in their last dentist visit, the cause of caries, the frequency of tooth brushing, the material used for oral hygiene, the duration of tooth brushing, method of tooth brushing, and tooth sites most brushed, which showed a significant association between children and their parents (p<0.01). Correct knowledge given to the children by their families will positively affect the oral-dental health of the children. Thus, firstly, correct knowledge should be given to the parents so that they can successfully carry out their responsibility in being the correct model for their children in oral-dental health.

  11. Compression induced phase transition of nematic brush: A mean-field theory study.

    Science.gov (United States)

    Tang, Jiuzhou; Zhang, Xinghua; Yan, Dadong

    2015-11-28

    Responsive behavior of polymer brush to the external compression is one of the most important characters for its application. For the flexible polymer brush, in the case of low grafting density, which is widely studied by the Gaussian chain model based theory, the compression leads to a uniform deformation of the chain. However, in the case of high grafting density, the brush becomes anisotropic and the nematic phase will be formed. The normal compression tends to destroy the nematic order, which leads to a complex responsive behaviors. Under weak compression, chains in the nematic brush are buckled, and the bending energy and Onsager interaction give rise to the elasticity. Under deep compression, the responsive behaviors of the nematic polymer brush depend on the chain rigidity. For the compressed rigid polymer brush, the chains incline to re-orientate randomly to maximize the orientational entropy and its nematic order is destroyed. For the compressed flexible polymer brush, the chains incline to fold back to keep the nematic order. A buckling-folding transition takes place during the compressing process. For the compressed semiflexible brush, the chains are collectively tilted to a certain direction, which leads to the breaking of the rotational symmetry in the lateral plane. These responsive behaviors of nematic brush relate to the properties of highly frustrated worm-like chain, which is hard to be studied by the traditional self-consistent field theory due to the difficulty to solve the modified diffusion equation. To overcome this difficulty, a single chain in mean-field theory incorporating Monte Carlo simulation and mean-field theory for the worm-like chain model is developed in present work. This method shows high performance for entire region of chain rigidity in the confined condition.

  12. Factors Affecting Oral Hygiene and Tooth Brushing in Preschool Children, Shiraz/Iran.

    Science.gov (United States)

    S, Shaghaghian; M, Zeraatkar

    2017-06-01

    Inadequate tooth brushing and inappropriate oral hygiene can lead to dental caries, the most common chronic diseases of childhood with several side effects. To evaluate factors affecting on preschool children's oral hygiene and tooth brushing in Shiraz, Iran. In this cross-sectional study, we selected 453 children registered in Shiraz kindergartens in 2013 by randomized cluster sampling. The children's tooth brushing and oral hygiene were assessed using a reliable and valid questionnaire and Simplified Debris Index (DI-S), respectively. A dental student examined all the children in each kindergarten to determine their DI-S. The relationship between the children's demographic variables and their oral hygiene and tooth brushing status were evaluated. Tooth brushing for 272 children (71.2%) had been started after the age of 2 years. The teeth in 96 children (24.2%) had been brushed lower than once daily. The mean of the children's DI-S was 1.19 ± (0.77). The DI-S of only 126 children (31.8%) was found to be good and very good. After controlling the effect of confounding factors, we found that the children's tooth brushing frequency was significantly associated with the number of children in the family and mothers' employment status. The age at which tooth brushing had been started was significantly associated with the fathers' education. Furthermore, the DI-S was associated with children's age, number of the children in the family, and their mothers' education. Oral hygiene and tooth brushing of the preschool children were not in a desirable status. Interventional procedures, especially educational programs, are recommended for children and their parents. These programs seem to be more necessary for older children, low socioeconomic families, and families with more than one child.

  13. Features of Running Brush Motors in Dry Nitrogen Environment When Using in Electrohydraulic Actuators

    Directory of Open Access Journals (Sweden)

    Y. A. Petrov

    2014-01-01

    Full Text Available The work concerns the constructive characteristics optimization of brushless D.C. (direct current motors used in electromechanical spacecraft drives.The spacecraft electromechanical drives and units use rather widely the brushless D.C. motors in which a motor commutator is replaced with more reliable semiconductor commutator controlled by the rotor position sensors. However, these motors are of low power.Electrohydraulic actuators (EHA use simple permanent-magnet motors (PMM of rather high power and commutator motors with graphite brush variable contacts.High reliability of brush motors, and, therefore a reliability of EHA in general, substantially depends on the quality of motor commutator operation. There are different reasons for a possible impact on the normal motor commutator operation. One of them is brush wear. Sparking brushes and burning commutator bars are possible in case brushes are poorly grinded to fit, brushes cannot freely move true in the brush holder box, and in case an incorrect force to clamp brushes to the commutator is chosen.It is established that drive wear resistance and operability depends on the gas environment composition being under sealed motor housing. In dry nitrogen environment brush wear suddenly raises because of the changing tribological performances of the commutator thus leading to essentially falling isolation resistance and no motor start.It is recommended to fill a space under sealed motor housing with air. Positive experience of operating spacecraft device containers with mobile electromechanical couples allowed us to find that in this case a dew point of filled air must be minus 20˚C.The paper offers an electromechanical alternative of design to the electrohydraulic actuators, with a ball-screw gear of the actuation mechanism, possessing a number of advantages.

  14. Factors Affecting Oral Hygiene and Tooth Brushing in Preschool Children, Shiraz/Iran

    Science.gov (United States)

    S, Shaghaghian; M, Zeraatkar

    2017-01-01

    Statement of Problem: Inadequate tooth brushing and inappropriate oral hygiene can lead to dental caries, the most common chronic diseases of childhood with several side effects. Objectives: To evaluate factors affecting on preschool children’s oral hygiene and tooth brushing in Shiraz, Iran Materials and Methods: In this cross-sectional study, we selected 453 children registered in Shiraz kindergartens in 2013 by randomized cluster sampling. The children’s tooth brushing and oral hygiene were assessed using a reliable and valid questionnaire and Simplified Debris Index (DI-S), respectively. A dental student examined all the children in each kindergarten to determine their DI-S. The relationship between the children’s demographic variables and their oral hygiene and tooth brushing status were evaluated. Results: Tooth brushing for 272 children (71.2%) had been started after the age of 2 years. The teeth in 96 children (24.2%) had been brushed lower than once daily. The mean of the children’s DI-S was 1.19 ± (0.77). The DI-S of only 126 children (31.8%) was found to be good and very good. After controlling the effect of confounding factors, we found that the children’s tooth brushing frequency was significantly associated with the number of children in the family and mothers’ employment status. The age at which tooth brushing had been started was significantly associated with the fathers’ education. Furthermore, the DI-S was associated with children’s age, number of the children in the family, and their mothers’ education. Conclusions: Oral hygiene and tooth brushing of the preschool children were not in a desirable status. Interventional procedures, especially educational programs, are recommended for children and their parents. These programs seem to be more necessary for older children, low socioeconomic families, and families with more than one child. PMID:28959771

  15. A hybrid floating brush seal (HFBS) for improved sealing and wear performance in turbomachinery applications

    Science.gov (United States)

    Lattime, Scott Byran

    A conceptually new type of seal has been developed for gas turbine applications which dramatically reduces wear and leakage associated with current labyrinth and brush seal technologies. The Hybrid Floating Brush Seal (HFBS) combines brush seal and film riding face seal technologies to create a hybrid seal that allows both axial and radial excursions of the sealed shaft, while simultaneously eliminating interface surface speeds (friction and heat) between the rotor and the brush material that characterize standard brush seal technology. A simple test rig was designed to evaluate feasibility of the HFBS under relatively low pressures and rotational speeds (50psig, 5krpm). A second test stand was created to study the effects of centrifugal force on bristle deflection. A third test facility was constructed for prototype development and extensive room temperature testing at moderate pressures and fairly high rotational speeds (100psig, 40krpm). This test rig also allowed the evaluation of the HFBS during axial movement of a rotating shaft. An analytical model to predict the effects of centrifugal force on the bristles of a rotating brush seal was developed. Room temperature analysis of the HFBS proved successful for relatively high operating rotational velocities at moderate pressures with very acceptable leakage rates for gas turbine engines. Brush seals were able to track rotor speeds up to 24krpm while maintaining sealing integrity. The HFBS's ability to function under axial shaft displacement and synchronous dynamic radial loading was also proven successful. Hydrodynamic performance of the face seal was proven to provide adequate stiffness and load carrying capacity to keep the brush seal from contacting the face seal at pressure drops across the brush of up to 100psi. Leakage performance over standard brush seal and labyrinth technology was quite dramatic. The HFBS showed its sealing advantage using much higher radial interference between the rotor and the bristle

  16. Development of the Upgraded DC Brush Gear Motor for Spacebus Platforms

    Science.gov (United States)

    Berning, Robert H.; Viout, Olivier

    2010-01-01

    The obsolescence of materials and processes used in the manufacture of traditional DC brush gear motors has necessitated the development of an upgraded DC brush gear motor (UBGM). The current traditional DC brush gear motor (BGM) design was evaluated using Six-Sigma process to identify potential design and production process improvements. The development effort resulted in a qualified UBGM design which improved manufacturability and reduced production costs. Using Six-Sigma processes and incorporating lessons learned during the development process also improved motor performance for UBGM making it a more viable option for future use as a deployment mechanism in space flight applications.

  17. Experimental and theoretical rotordynamic stiffness coefficients for a three-stage brush seal

    Science.gov (United States)

    Pugachev, A. O.; Deckner, M.

    2012-08-01

    Experimental and theoretical results are presented for a multistage brush seal. Experimental stiffness is obtained from integrating circumferential pressure distribution measured in seal cavities. A CFD analysis is used to predict seal performance. Bristle packs are modeled by the porous medium approach. Leakage is predicted well by the CFD method. Theoretical stiffness coefficients are in reasonable agreement with the measurements. Experimental results are also compared with a three-teeth-on-stator labyrinth seal. The multistage brush seal gives about 60% leakage reduction over the labyrinth seal. Rotordynamic stiffness coefficients are also improved: the brush seal has positive direct stiffness and smaller cross-coupled stiffness.

  18. Diagnosis of intestinal and extra intestinal amoebiasis

    International Nuclear Information System (INIS)

    Lopez, Myriam Consuelo; Quiroz, Damian Arnoldo; Pinilla, Analida Elizabeth

    2007-01-01

    The objective is to carry out a review of the national and international literature as of the XXth century in order to update the advances for the diagnosis of complex odd Entamoeba histolytic / Entamoeba dispar and that of intestinal and extra intestinal amoebiasis that may be of use to the scientific community. As well as to unify the diagnostic criteria of this parasitosis known as a public health problem, and as a consequence of that, optimize the quality of population care. Data source: there was a systematic search for the scientific literature Publisher in Spanish and English since 1960 until today, this selection started on the first semester of 2006 until 2007, in the development of the line on intestinal and extra-intestinal amoebiasis of the Medical School of the National University of Colombia. A retrospective search process was carried out, systematically reviewing the most relevant articles as well as the products of this research line. In deciding how to make this article, there was a continuous search in different data bases such as Medline, SciELO and other bases in the library of the National University of Colombia, as well as other classical books related to the subject. For that purpose the terms amoebiasis, odd Entamoeba histolytic, Entamoeba, diagnosis, epidemiology, dysentery, amoebic liver abscess, were used. Studies selection: titles and abstracts were reviewed to select the original publications and the most representative ones related to this article's subject. Data extraction: the articles were classified according to the subject, the chronology and the authors according to the scientific contribution to solve the problem. Synthesis of the data: in the fi rst instance, a chronological critical analysis was carried out to order and synthesize the progress made in the diagnosis until confirmation of the experts' agreements in the field of amoebiasis was obtained throughout the world. Conclusion: this article summarizes what has taken place

  19. The California Border Health Collaborative: A Strategy for Leading the Border to Better Health

    Directory of Open Access Journals (Sweden)

    Charles Edwards Matthews III

    2015-05-01

    Full Text Available There are hundreds of departments and organizations working on border health issues in the California/Baja California border region trying to protect and improve health without a collaborative structure that integrates jurisdictions and organizations. As a result, there is a need to effectively improve the health in the border region by coordinating these organizations to work together and benefit from each other’s best practices. The newly developed California Border Health Collaborative (CBHC can provide the leadership and collaborative culture to positively improve the health of the border region. This article aims to describe the development process of this collaborative to include key ingredients to success, the roles of mulit-level jurisdictions, and policy implications.This article describes the methods used to develop key aspects of collaborative leadership, strategic alignment and a common vision toward the building of this collective impact approach to border health. In addition, we describe the role of key local County (County of San Diego Live Well San Diego initiative, State, (California Department of Public Health- Office of Binational Border Health, Federal (US-Mexico Border Health Commission’s Leaders across Borders, Academia (e.g., University of California San Diego and San Diego State University and non-profit entities (e.g., Project Concern International, San Ysidro Health Center in forming the BHCC. Evaluating the consortium development process included a literature review of similar processes, a review of internal documents and an analysis of developmental events. To this point the CBHC has built a strong, cohesive collaborative on the U.S. side of the border. It is sharing and leveraging local expertise to address many border health issues. Even more importantly, the BHCC has reached a key stage in which it can effectively engage its Baja California, Mexico counterparts in a manner that will prove extremely powerful

  20. Radiation safety without borders initiative

    International Nuclear Information System (INIS)

    Dibblee, Martha; Dickson, Howard; Krieger, Ken; Lopez, Jose; Waite, David; Weaver, Ken

    2008-01-01

    The Radiation Safety Without Borders (RSWB) initiative provides peer support to radiation safety professionals in developing countries, which bolsters the country's infrastructure and may lead the way for IRPA Associate membership. The Health Physics Society (HPS) recognizes that many nations do not possess the infrastructure to adequately control and beneficially use ionizing radiation. In a substantial number of countries, organized radiation protection programs are minimal. The RSWB initiative relies on HPS volunteers to assist their counterparts in developing countries with emerging health physics and radiation safety programs, but whose resources are limited, to provide tools that promote and support infrastructure and help these professionals help themselves. RSWB experience to date has shown that by providing refurbished instruments, promoting visits to a HPS venue, or visiting a country just to look provide valuable technical and social infrastructure experiences often missing in the developing nation's cadre of radiation safety professionals. HPS/RSWB with the assistance of the International Atomic Energy Agency (IAEA) pairs chapters with a country, with the expectation that the country's professional radiation safety personnel will form a foreign HPS chapter, and the country eventually will become an IRPA Associate. Although still in its formative stage, RSWB nonetheless has gotten valuable information in spite of the small number of missions. The RSWB initiative continues to have significant beneficial impacts, including: Improving the radiation safety infrastructure of the countries that participate; Assisting those countries without professional radiation safety societies to form one; Strengthening the humanitarian efforts of the United States; Enhancing Homeland Security efforts through improved control of radioactive material internationally. Developing countries, including those in Latin America, underwritten by IAEA, may take advantage of resources