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Sample records for cells specific removal

  1. Metabolism of /sup 125/I-atrial natriuretic factor by vascular smooth muscle cells. Evidence for a peptidase that specifically removes the COOH-terminal tripeptide

    SciTech Connect

    Johnson, G.R.; Arik, L.; Foster, C.J.

    1989-07-15

    The addition of 200 pM monoiodinated human atrial natriuretic factor-(99-126) (125I-hANF) to cultured bovine aortic smooth muscle cells at 37/degree/C resulted in a rapid clearance from the medium (t1/2 approximately 7.5 min). Within 5 min, (125I)iodotyrosine126 (125I-Y), Arg125-(125I)iodotyrosine126 (125I-RY) and Phe124-Arg-(125)iodotyrosine126 (125I-FRY) appeared in the medium. The identities of these degradation products were confirmed by (1) retention time on high performance liquid chromatography (HPLC) relative to standards, (2) products generated by digestion with aminopeptidase M, and (3) the absence of the Met110. Preincubation of the cells with ammonium chloride or chloroquine resulted in a significant increase in the intracellular accumulation of radiolabel, indicative of endocytosis and rapid delivery of 125I-hANF to an acidic intracellular compartment (endosome and/or lysosome). Neither ammonium chloride, chloroquine, nor excess unlabeled hANF blocked the rapid appearance in the medium of 125I-RY or 125I-FRY. Bestatin inhibited the generation of 125I-RY, with a concomitant increase in 125I-FRY, suggesting that the 125I-RY is produced by aminopeptidase action on 125I-FRY. The endopeptidase 24.11 (enkephalinase) inhibitor, SCH 39370, did not inhibit the formation of 125I-FRY. These results provide evidence of a peptidase capable of specifically removing the COOH-terminal tripeptide from 125I-hANF. The COOH-terminal tripeptide, Phe124-Arg-Tyr126, was also isolated from cell digests of hANF by HPLC and its identity confirmed by amino acid analysis. Since it is generally believed that the COOH-terminal tripeptide is critical to many of atrial natriuretic factor-(99-126)'s bioactivities, this enzyme may be involved in the inactivation of atrial natriuretic factor-(99-126) in target tissues.

  2. Dust Removal from Solar Cells

    NASA Technical Reports Server (NTRS)

    Ashpis, David E. (Inventor)

    2015-01-01

    A solar panel cleaning device includes a solar panel having a plurality of photovoltaic cells arranged in rows and embedded in the solar panel with space between the rows. A transparent dielectric overlay is affixed to the solar panel. A plurality of electrode pairs each of which includes an upper and a lower electrode are arranged on opposite sides of the transparent dielectric and are affixed thereto. The electrodes may be transparent electrodes which may be arranged without concern for blocking sunlight to the solar panel. The solar panel may be a dielectric and its dielectric properties may be continuously and spatially variable. Alternatively the dielectric used may have dielectric segments which produce different electrical field and which affects the wind "generated."

  3. Dust removal from solar cells

    NASA Technical Reports Server (NTRS)

    Ashpis, David E. (Inventor)

    2011-01-01

    A solar panel cleaning device includes a solar panel having a plurality of photovoltaic cells arranged in rows and embedded in the solar panel with space between the rows. A transparent dielectric overlay is affixed to the solar panel. A plurality of electrode pairs each of which includes an upper and a lower electrode are arranged on opposite sides of the transparent dielectric and are affixed thereto. The electrodes may be transparent electrodes which may be arranged without concern for blocking sunlight to the solar panel. The solar panel may be a dielectric and its dielectric properties may be continuously and spatially variable. Alternatively the dielectric used may have dielectric segments which produce different electrical field and which affects the wind "generated."

  4. Mechanisms regulating phosphatase specificity and the removal of individual phosphorylation sites during mitotic exit.

    PubMed

    Rogers, Samuel; McCloy, Rachael; Watkins, D Neil; Burgess, Andrew

    2016-07-01

    Entry into mitosis is driven by the activity of kinases, which phosphorylate over 7000 proteins on multiple sites. For cells to exit mitosis and segregate their genome correctly, these phosphorylations must be removed in a specific temporal order. This raises a critical and important question: how are specific phosphorylation sites on an individual protein removed? Traditionally, the temporal order of dephosphorylation was attributed to decreasing kinase activity. However, recent evidence in human cells has identified unique patterns of dephosphorylation during mammalian mitotic exit that cannot be fully explained by the loss of kinase activity. This suggests that specificity is determined in part by phosphatases. In this review, we explore how the physicochemical properties of an individual phosphosite and its surrounding amino acids can affect interactions with a phosphatase. These positive and negative interactions in turn help determine the specific pattern of dephosphorylation required for correct mitotic exit. PMID:27417119

  5. Debris Removal Project K West Canister Cleaning System Performance Specification

    SciTech Connect

    FARWICK, C.C.

    1999-12-09

    Approximately 2,300 metric tons Spent Nuclear Fuel (SNF) are currently stored within two water filled pools, the 105 K East (KE) fuel storage basin and the 105 K West (KW) fuel storage basin, at the U.S. Department of Energy, Richland Operations Office (RL). The SNF Project is responsible for operation of the K Basins and for the materials within them. A subproject to the SNF Project is the Debris Removal Subproject, which is responsible for removal of empty canisters and lids from the basins. Design criteria for a Canister Cleaning System to be installed in the KW Basin. This documents the requirements for design and installation of the system.

  6. Electrochemical antimony removal from accumulator acid: results from removal trials in laboratory cells.

    PubMed

    Bergmann, M E Henry; Koparal, A Savas

    2011-11-30

    Regeneration of spent accumulator acid could be an alternative process for crystallization, neutralisation and disposal. Therefore, for the first time in a study of the possibilities of electrochemical removal of antimony and accumulator acid regeneration on a laboratory scale, two synthetic and several real systems containing sulfuric acid of concentrations ranging between 28% and 36%, and antimony species were tested. Discontinuous electrochemical reactors with anion exchange membranes were successfully used in these experiments, which were conducted at a temperature of 35°C. Removal of antimony using cells that were not divided by a separator, however, was not possible. In selected experiments, by varying the electrode material, type of electrolyte, and cell current, the concentration of antimony could be reduced from the range of 5 ppm to 0.15 ppm. This resulted in current efficiencies between 0.00002% and 0.001%, and in specific electroenergy demands between 100 Wh L(-1) and 2000 Wh L(-1). In other experiments on substances with antimony contents up to 3500 mg L(-1), the current efficiencies obtained were more than a thousandfold higher. In contrast to the formally high relative energy consumption parameters absolute demand parameters are relatively small and favour the electrochemical method in small scale application. Besides plate electrodes, 3D-cathodes were used. Copper- and graphite cathodes produced the best results. PMID:21978586

  7. Specific removal of TACC3–ch-TOG–clathrin at metaphase deregulates kinetochore fiber tension

    PubMed Central

    Cheeseman, Liam P.; Harry, Edward F.; McAinsh, Andrew D.; Prior, Ian A.; Royle, Stephen J.

    2013-01-01

    Summary Microtubule-associated proteins of the mitotic spindle are thought to be important for the initial assembly and the maintenance of spindle structure and function. However, distinguishing assembly and maintenance roles for a given protein is difficult. Most experimental methods for protein inactivation are slow and therefore affect both assembly and maintenance. Here, we have used ‘knocksideways’ to rapidly (∼5 minutes) and specifically remove TACC3–ch-TOG–clathrin non-motor complexes from kinetochore fibers (K-fibers). This method allows the complex to be inactivated at defined stages of mitosis. Removal of TACC3–ch-TOG–clathrin after nuclear envelope breakdown caused severe delays in chromosome alignment. Inactivation at metaphase, following a normal prometaphase, significantly delayed progression to anaphase. In these cells, K-fiber tension was reduced and the spindle checkpoint was not satisfied. Surprisingly, there was no significant loss of K-fiber microtubules, even after prolonged removal. TACC3–ch-TOG–clathrin removal during metaphase also resulted in a decrease in spindle length and significant alteration in kinetochore dynamics. Our results indicate that TACC3–ch-TOG–clathrin complexes are important for the maintenance of spindle structure and function as well as for initial spindle assembly. PMID:23532825

  8. Gas diffusion cell removes carbon dioxide from occupied airtight enclosures

    NASA Technical Reports Server (NTRS)

    1964-01-01

    Small, lightweight permeable cell package separates and removes carbon dioxide from respiratory gas mixtures. The cell is regenerative while chemically inert in the presence of carbon dioxide so that only adsorption takes place.

  9. Surface-modified gold nanorods for specific cell targeting

    NASA Astrophysics Data System (ADS)

    Wang, Chan-Ung; Arai, Yoshie; Kim, Insun; Jang, Wonhee; Lee, Seonghyun; Hafner, Jason H.; Jeoung, Eunhee; Jung, Deokho; Kwon, Youngeun

    2012-05-01

    Gold nanoparticles (GNPs) have unique properties that make them highly attractive materials for developing functional reagents for various biomedical applications including photothermal therapy, targeted drug delivery, and molecular imaging. For in vivo applications, GNPs need to be prepared with very little or negligible cytotoxicitiy. Most GNPs are, however, prepared using growth-directing surfactants such as cetyl trimethylammonium bromide (CTAB), which are known to have considerable cytotoxicity. In this paper, we describe an approach to remove CTAB to a non-toxic concentration. We optimized the conditions for surface modification with methoxypolyethylene glycol thiol (mPEG), which replaced CTAB and formed a protective layer on the surface of gold nanorods (GNRs). The cytotoxicities of pristine and surface-modified GNRs were measured in primary human umbilical vein endothelial cells and human cell lines derived from hepatic carcinoma cells, embryonic kidney cells, and thyroid papillary carcinoma cells. Cytotoxicity assays revealed that treating cells with GNRs did not significantly affect cell viability except for thyroid papillary carcinoma cells. Thyroid cancer cells were more susceptible to residual CTAB, so CTAB had to be further removed by dialysis in order to use GNRs for thyroid cell targeting. PEGylated GNRs are further modified to present monoclonal antibodies that recognize a specific surface marker, Na-I symporter, for thyroid cells. Antibody-conjugated GNRs specifically targeted human thyroid cells in vitro.

  10. Reaction heat used in static water removal from fuel cells

    NASA Technical Reports Server (NTRS)

    Platner, J. L.

    1966-01-01

    Reaction heat is used for removal of water formed at the hydrogen fuel electrode in a hydrogen-oxygen fuel cell. A portion of the heat inherent in the fuel cell current generation reaction is used to transfer excess water into water vapor and cause it to be exhausted from the cell by a porous vapor transport membrane adjoining a vapor cavity.

  11. Benchmark specifications for EBR-II shutdown heat removal tests

    SciTech Connect

    Sofu, T.; Briggs, L. L.

    2012-07-01

    Argonne National Laboratory (ANL) is hosting an IAEA-coordinated research project on benchmark analyses of sodium-cooled fast reactor passive safety tests performed at the Experimental Breeder Reactor-II (EBR-II). The benchmark project involves analysis of a protected and an unprotected loss of flow tests conducted during an extensive testing program within the framework of the U.S. Integral Fast Reactor program to demonstrate the inherently safety features of EBR-II as a pool-type, sodium-cooled fast reactor prototype. The project is intended to improve the participants' design and safety analysis capabilities for sodium-cooled fast reactors through validation and qualification of safety analysis codes and methods. This paper provides a description of the EBR-II tests included in the program, and outlines the benchmark specifications being prepared to support the IAEA-coordinated research project. (authors)

  12. AMMONIA REMOVAL FROM MAMMALIAN CELL CULTURE MEDIUM

    EPA Science Inventory

    Metabolites such as ammonia and lactic formed during mammalian cell culture can frequently be toxic to the cells themselves beyond a threshold concentration of the metabolites. ell culture conducted in the presence of such accumulated metabolites is therefore limited in productiv...

  13. Regulation of endothelial cell differentiation and specification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The circulatory system is the first organ system to develop in the vertebrate embryo and is critical throughout gestation for the delivery of oxygen and nutrients to, as well as removal of metabolic waste products from, growing tissues. Endothelial cells, which constitute the luminal layer of all bl...

  14. Cell-Type-Specific Optogenetics in Monkeys.

    PubMed

    Namboodiri, Vijay Mohan K; Stuber, Garret D

    2016-09-01

    The recent advent of technologies enabling cell-type-specific recording and manipulation of neuronal activity spurred tremendous progress in neuroscience. However, they have been largely limited to mice, which lack the richness in behavior of primates. Stauffer et al. now present a generalizable method for achieving cell-type specificity in monkeys. PMID:27610562

  15. Cell specific, variable density, polymer microspheres

    NASA Technical Reports Server (NTRS)

    Yen, Shiao-Ping S. (Inventor); Rembaum, Alan (Inventor); Molday, Robert S. (Inventor)

    1977-01-01

    Biocompatible polymeric microspheres having an average diameter below about 3 microns and having density at least 15% greater or lesser than organic cells and having covalent binding sites are provided in accordance with this invention. The microspheres are obtained by copolymerizing a hydroxy or amine substituted acrylic monomer such as hydroxyethylmethacrylate with a light or dense comonomer such as a fluoromonomer. A lectin or antibody is bound to the hydroxy or amine site of the bead to provide cell specificity. When added to a cell suspension the marked bead will specifically label the cell membrane by binding to specific receptor sites thereon. The labelled membrane can then be separated by density gradient centrifugation.

  16. FOXA1 defines cancer cell specificity

    PubMed Central

    Zhang, Gaihua; Zhao, Yongbing; Liu, Yi; Kao, Li-Pin; Wang, Xiao; Skerry, Benjamin; Li, Zhaoyu

    2016-01-01

    A transcription factor functions differentially and/or identically in multiple cell types. However, the mechanism for cell-specific regulation of a transcription factor remains to be elucidated. We address how a single transcription factor, forkhead box protein A1 (FOXA1), forms cell-specific genomic signatures and differentially regulates gene expression in four human cancer cell lines (HepG2, LNCaP, MCF7, and T47D). FOXA1 is a pioneer transcription factor in organogenesis and cancer progression. Genomewide mapping of FOXA1 by chromatin immunoprecipitation sequencing annotates that target genes associated with FOXA1 binding are mostly common to these cancer cells. However, most of the functional FOXA1 target genes are specific to each cancer cell type. Further investigations using CRISPR-Cas9 genome editing technology indicate that cell-specific FOXA1 regulation is attributable to unique FOXA1 binding, genetic variations, and/or potential epigenetic regulation. Thus, FOXA1 controls the specificity of cancer cell types. We raise a “flower-blooming” hypothesis for cell-specific transcriptional regulation based on these observations. PMID:27034986

  17. Specification of germ cell fate in mice.

    PubMed Central

    Saitou, Mitinori; Payer, Bernhard; Lange, Ulrike C; Erhardt, Sylvia; Barton, Sheila C; Surani, M Azim

    2003-01-01

    An early fundamental event during development is the segregation of germ cells from somatic cells. In many organisms, this is accomplished by the inheritance of preformed germ plasm, which apparently imposes transcriptional repression to prevent somatic cell fate. However, in mammals, pluripotent epiblast cells acquire germ cell fate in response to signalling molecules. We have used single cell analysis to study how epiblast cells acquire germ cell competence and undergo specification. Germ cell competent cells express Fragilis and initially progress towards a somatic mesodermal fate. However, a subset of these cells, the future primordial germ cells (PGCs), then shows rapid upregulation of Fragilis with concomitant transcriptional repression of a number of genes, including Hox and Smad genes. This repression may be a key event associated with germ cell specification. Furthermore, PGCs express Stella and other genes, such as Oct-4 that are associated with pluripotency. While these molecules are also detected in mature oocytes as maternally inherited factors, their early role is to regulate development and maintain pluripotency, and they do not serve the role of classical germline determinants. PMID:14511483

  18. Apoptin: specific killer of tumor cells?

    PubMed

    Tavassoli, M; Guelen, L; Luxon, B A; Gäken, J

    2005-08-01

    In the early 1990s it was discovered that the VP3/Apoptin protein encoded by the Chicken Anemia virus (CAV) possesses an inherent ability to specifically kill cancer cells. Apoptin was found to be located in the cytoplasm of normal cells while in tumor cells it was localized mainly in the nucleus.(1) These differences in the localization pattern were suggested to be the main mechanism by which normal cells show resistance to Apoptin-mediated cell killing. Although the mechanism of action of Apoptin is presently unknown, it seems to function by the induction of programmed cell death (PCD) after translocation from the cytoplasm to the nucleus and arresting the cell cycle at G2/M, possibly by interfering with the cyclosome.(2) In addition, cancer specific phosphorylation of Threonine residue 108 has been suggested to be important for Apoptin's function to kill tumor cells.(3) In contrast to the large number of publications reporting that nuclear localization, induction of PCD and phosphorylation of Apoptin is restricted to cancer cells, several recent studies have shown that Apoptin has the ability to migrate to the nucleus and induce PCD in some of the normal cell lines tested. There is evidence that high protein expression levels as well as the cellular growth rate may influence Apoptin's ability to specifically kill tumor cells. Thus far both in vitro and in vivo studies indicate that Apoptin is a powerful apoptosis inducing protein with a promising prospective utility in cancer therapy. However, here we show that several recent findings contradict some of the earlier results on the tumor specificity of Apoptin, thus creating some controversy in the field. The aim of this article is to review the available data, some published and some unpublished, which either agree or contradict the reported "black and white" tumor cell specificity of Apoptin. Understanding what factors appear to influence its function should help to develop Apoptin into a potent anti

  19. Apoptin: Specific killer of tumor cells?

    PubMed Central

    Tavassoli, M.; Guelen, L.; Luxon, B. A.; Gäken, J.

    2010-01-01

    In the early 1990s it was discovered that the VP3/Apoptin protein encoded by the Chicken Anemia virus (CAV) possesses an inherent ability to specifically kill cancer cells. Apoptin was found to be located in the cytoplasm of normal cells while in tumor cells it was localized mainly in the nucleus.1 These differences in the localization pattern were suggested to be the main mechanism by which normal cells show resistance to Apoptin-mediated cell killing. Although the mechanism of action of Apoptin is presently unknown, it seems to function by the induction of programmed cell death (PCD) after translocation from the cytoplasm to the nucleus and arresting the cell cycle at g2/M, possibly by interfering with the cyclosome.2 In addition, cancer specific phosphorylation of Threonine residue 108 has been suggested to be important for Apoptin’s function to kill tumor cells.3 In contrast to the large number of publications reporting that nuclear localization, induction of PCD and phosphorylation of Apoptin is restricted to cancer cells, several recent studies have shown that Apoptin has the ability to migrate to the nucleus and induce PCD in some of the normal cell lines tested. There is evidence that high protein expression levels as well as the cellular growth rate may influence Apoptin’s ability to specifically kill tumor cells. Thus far both in vitro and in vivo studies indicate that Apoptin is a powerful apoptosis inducing protein with a promising prospective utility in cancer therapy. However, here we show that several recent findings contradict some of the earlier results on the tumor specificity of Apoptin, thus creating some controversy in the field. The aim of this article is to review the available data, some published and some unpublished, which either agree or contradict the reported “black and white” tumor cell specificity of Apoptin. Understanding what factors appear to influence its function should help to develop Apoptin into a potent anti

  20. Primordial Germ Cell Specification and Migration

    PubMed Central

    Marlow, Florence

    2015-01-01

    Primordial germ cells are the progenitor cells that give rise to the gametes. In some animals, the germline is induced by zygotic transcription factors, whereas in others, primordial germ cell specification occurs via inheritance of maternally provided gene products known as germ plasm. Once specified, the primordial germ cells of some animals must acquire motility and migrate to the gonad in order to survive. In all animals examined, perinuclear structures called germ granules form within germ cells. This review focuses on some of the recent studies, conducted by several groups using diverse systems, from invertebrates to vertebrates, which have provided mechanistic insight into the molecular regulation of germ cell specification and migration. PMID:26918157

  1. Cell cycle-specific effects of lovastatin.

    PubMed Central

    Jakóbisiak, M; Bruno, S; Skierski, J S; Darzynkiewicz, Z

    1991-01-01

    Lovastatin (LOV), the drug recently introduced to treat hypercholesteremia, inhibits the synthesis of mevalonic acid. The effects of LOV on the cell cycle progression of the human bladder carcinoma T24 cell line expressing activated p21ras were investigated. At a concentration of 2-10 microM, LOV arrested cells in G1 and also prolonged--or arrested a minor fraction of cells in--the G2 phase of the cell cycle; at a concentration of 50 microM, LOV was cytotoxic. The cytostatic effects were reversed by addition of exogenous mevalonate. Cells arrested in the cycle by LOV were viable for up to 72 hr and did not show any changes in RNA or protein content or chromatin condensation, which would be typical of either unbalanced growth or deep quiescence. The expression of the proliferation-associated nuclear proteins Ki-67 and p105 in these cells was reduced by up to 72% and 74%, respectively, compared with exponentially growing control cells. After removal of LOV, the cells resumed progression through the cycle; they entered S phase asynchronously after a lag of approximately 6 hr. Because mevalonate is essential for the posttranslational modification (isoprenylation) of p21ras, which in turn allows this protein to become attached to the cell membrane, the data suggest that the LOV-induced G1 arrest may be a consequence of the loss of the signal transduction capacity of p21ras. Indeed, while exposure of cells to LOV had no effect on the cellular content of p21ras (detected immunocytochemically), it altered the intracellular location of this protein, causing its dissociation from the cell membrane and translocation toward the cytoplasm and nucleus. However, it is also possible that inhibition of isoprenylation of proteins other than p21ras (e.g., nuclear lamins) by LOV may be responsible for the observed suppression of growth of T24 cells. Images PMID:1673788

  2. Cell specific, variable density, polymer microspheres

    NASA Technical Reports Server (NTRS)

    Yen, Shiao-Ping S. (Inventor); Rembaum, Alan (Inventor); Molday, Robert S. (Inventor)

    1978-01-01

    Biocompatible polymeric microspheres having an average diameter below about 3 microns and having a density at least 15% greater or lesser than organic cells and having covalent binding sites are provided in accordance with this invention. The microspheres are obtained by copolymerizing a hydroxy or amine substituted acrylic monomer such as hydroxyethylmethacrylate with a light or dense comonomer such as a fluoromonomer. A lectin or antibody is bound to the hydroxy or amine site of the bead to provide cell specificity. When added to a cell suspension the marked bead will specifically label the cell membrane by binding to specific receptor sites thereon. The labelled membrane can then be separated by density gradient centrifugation.

  3. Matrix elasticity directs stem cell lineage specification

    NASA Astrophysics Data System (ADS)

    Discher, Dennis

    2010-03-01

    Adhesion of stem cells - like most cells - is not just a membrane phenomenon. Most tissue cells need to adhere to a ``solid'' for viability, and over the last decade it has become increasingly clear that the physical ``elasticity'' of that solid is literally ``felt'' by cells. Here we show that Mesenchymal Stem Cells (MSCs) specify lineage and commit to phenotypes with extreme sensitivity to the elasticity typical of tissues [1]. In serum only media, soft matrices that mimic brain appear neurogenic, stiffer matrices that mimic muscle are myogenic, and comparatively rigid matrices that mimic collagenous bone prove osteogenic. Inhibition of nonmuscle myosin II activity blocks all elasticity directed lineage specification, which indicates that the cytoskeleton pulls on matrix through adhesive attachments. Results have significant implications for `therapeutic' stem cells and have motivated development of a proteomic-scale method to identify mechano-responsive protein structures [2] as well as deeper physical studies of matrix physics [3] and growth factor pathways [4]. [4pt] [1] A. Engler, et al. Matrix elasticity directs stem cell lineage specification. Cell (2006).[0pt] [2] C.P. Johnson, et al. Forced unfolding of proteins within cells. Science (2007).[0pt] [3] A.E.X. Brown, et al. Multiscale mechanics of fibrin polymer: Gel stretching with protein unfolding and loss of water. Science (2009).[0pt] [4] D.E. Discher, et al. Growth factors, matrices, and forces combine and control stem cells. Science (2009).

  4. Cadmium (II) removal mechanisms in microbial electrolysis cells.

    PubMed

    Colantonio, Natalie; Kim, Younggy

    2016-07-01

    Cadmium is a toxic heavy metal, causing serious environmental and human health problems. Conventional methods for removing cadmium from wastewater are expensive and inefficient for low concentrations. Microbial electrolysis cells (MECs) can simultaneously treat wastewater, produce hydrogen gas, and remove heavy metals with low energy requirements. Lab-scale MECs were operated to remove cadmium under various electric conditions: applied voltages of 0.4, 0.6, 0.8, and 1.0 V; and a fixed cathode potential of -1.0 V vs. Ag/AgCl. Regardless of the electric condition, rapid removal of cadmium was demonstrated (50-67% in 24 h); however, cadmium concentration in solution increased after the electric current dropped with depleted organic substrate under applied voltage conditions. For the fixed cathode potential, the electric current was maintained even after substrate depletion and thus cadmium concentration did not increase. These results can be explained by three different removal mechanisms: cathodic reduction; Cd(OH)2 precipitation; and CdCO3 precipitation. When the current decreased with depleted substrates, local pH at the cathode was no longer high due to slowed hydrogen evolution reaction (2H(+)+2e(-)→H2); thus, the precipitated Cd(OH)2 and CdCO3 started dissolving. To prevent their dissolution, sufficient organic substrates should be provided when MECs are used for cadmium removal. PMID:26970043

  5. Removal of sulfur contaminants in methanol for fuel cell applications

    SciTech Connect

    Lee, S.H.D.; Kumar, R.; Sederquist, R.

    1996-12-31

    Fuel cell power plants are being developed for transit bus and passenger car applications that use methanol as the on-board fuel. Commodity methanol by itself contains very little sulfur; however, it may occasionally be contaminated with up to about 1% diesel fuel or gasoline in current liquid-fuel distribution systems, leading to the presence of sulfur in the methanol fuel. This sulfur must be removed because of its deleterious effect on the reforming catalysts. International Fuel Cells has set the allowable sulfur limit in the methanol fuel at less than 1 ppm. The equilibrium adsorption isotherm and breakthrough data were used to assess the feasibility of developing a granular activated carbon adsorber for the removal of sulfur from transportation fuel cell systems.

  6. Autotrophic nitrite removal in the cathode of microbial fuel cells.

    PubMed

    Puig, Sebastià; Serra, Marc; Vilar-Sanz, Ariadna; Cabré, Marina; Bañeras, Lluís; Colprim, Jesús; Balaguer, M Dolors

    2011-03-01

    Nitrification to nitrite (nitritation process) followed by reduction to dinitrogen gas decreases the energy demand and the carbon requirements of the overall process of nitrogen removal. This work studies autotrophic nitrite removal in the cathode of microbial fuel cells (MFCs). Special attention was paid to determining whether nitrite is used as the electron acceptor by exoelectrogenic bacteria (biologic reaction) or by graphite electrodes (abiotic reaction). The results demonstrated that, after a nitrate pulse at the cathode, nitrite was initially accumulated; subsequently, nitrite was removed. Nitrite and nitrate can be used interchangeably as an electron acceptor by exoelectrogenic bacteria for nitrogen reduction from wastewater while producing bioelectricity. However, if oxygen is present in the cathode chamber, nitrite is oxidised via biological or electrochemical processes. The identification of a dominant bacterial member similar to Oligotropha carboxidovorans confirms that autotrophic denitrification is the main metabolism mechanism in the cathode of an MFC. PMID:21262566

  7. Monoclonal antibodies specific for sickle cell hemoglobin

    SciTech Connect

    Jensen, R.H.; Vanderlaan, M.; Grabske, R.J.; Branscomb, E.W.; Bigbee, W.L.; Stanker, L.H.

    1985-01-01

    Two mouse hybridoma cell lines were isolated which produce monoclonal antibodies that bind hemoglobin S. The mice were immunized with peptide-protein conjugates to stimulate a response to the amino terminal peptide of the beta chain of hemoglobin S, where the single amino acid difference between A and S occurs. Immunocharacterization of the antibodies shows that they bind specifically to the immunogen peptide and to hemoglobin S. The specificity for S is high enough that one AS cell in a mixture with a million AA cells is labeled by antibody, and such cells can be analyzed by flow cytometry. Immunoblotting of electrophoretic gels allows definitive identification of hemoglobin S as compared with other hemoglobins with similar electrophoretic mobility. 12 references, 4 figures.

  8. Specificity of human galectins on cell surfaces.

    PubMed

    Rapoport, E M; Bovin, N V

    2015-07-01

    Galectins are β-galactoside-binding proteins sharing homology in amino acid sequence of their carbohydrate-recognition domain. Their carbohydrate specificity outside cells has been studied previously. The main conclusion of these studies was that several levels of glycan ligand recognition exist for galectins: (i) disaccharide Galβ1-4GlcNAc (LN, N-acetyllactosamine) binds stronger than β-galactopyranose; (ii) substitution at O-2 and O-3 of galactose residue as well as core fragments ("right" from GlcNAc) provides significant increase in affinity; (iii) similarly glycosylated proteins can differ significantly in affinity to galectins. Information about the natural cellular receptors of galectins is limited. Until recently, it was impossible to study specificity of cell-bound galectins. A model based on controlled incorporation of a single protein into glycocalyx of cells and subsequent interaction of loaded cells with synthetic glycoprobes measured by flow cytometry made this possible recently. In this review, data about glycan specificity of proto-, chimera-, and tandem-repeat type galectins on the cell surface are systematized, and comparative analysis of the results with data on specificity of galectins in artificial systems was performed. The following conclusions from these studies were made: (i) cellular galectins have practically no ability to bind disaccharide LNn, but display affinity to 3'-substituted oligolactosamines and oligomers LNn; (ii) tandem-repeat type galectins recognize another disaccharide, namely Galβ1-3GlcNAc (Le(c)); (iii) on the cell surface, tandem-repeat type galectins conserve the ability to display high affinity to blood group antigens of ABH system; (iv) in general, when galectins are immersed into glycocalyx, they are more selective regarding glycan interactions. Thus, we conclude that competitive interaction of galectins with cell microenvironment (endogenous cell glycans) is the main factor providing selectivity of galectins in

  9. Learning LM Specificity for Ganglion Cells

    NASA Technical Reports Server (NTRS)

    Ahumada, Albert J.

    2015-01-01

    Unsupervised learning models have been proposed based on experience (Ahumada and Mulligan, 1990;Wachtler, Doi, Lee and Sejnowski, 2007) that allow the cortex to develop units with LM specific color opponent receptive fields like the blob cells reported by Hubel and Wiesel on the basis of visual experience. These models used ganglion cells with LM indiscriminate wiring as inputs to the learning mechanism, which was presumed to occur at the cortical level.

  10. Evaluation of Alternatives for Hanford 327 Building Hot Cell Removal and Transport

    SciTech Connect

    Stevens, Ray W.; Jasen, William G.

    2003-02-27

    The Department of Energy (DOE) Hanford site 327 Building, built in 1953, played a key role in reactor material and fuel research programs. The facility includes nine shielded hot cells, a fuel storage basin, dry sample storage, and a large inerted hot (SERF) cell. In 1996, the 327 Building was transferred from Pacific Northwest National Laboratory (PNNL) to Fluor Hanford, Inc., to begin the transition from the mission of irradiated fuel examination to stabilization and deactivation. In 2001, a multi-contractor team conducted a review of the concept of intact (one piece) removal, packaging, and disposal of the 327 hot cells. This paper focuses on challenges related to preparing the 327 Building hot cells for intact one-piece disposal as Low Level Waste (LLW) at the Hanford Site. These challenges, described in this paper, are threefold and include: Sampling and characterization of the cells for low level waste designation; Packaging of the cells for transportation and waste disposal; Transportation from the facility to the disposal site. The primary technical challenges in one-piece removal, packaging, and disposal of the hot cells involve the techniques required to characterize, remove, handle, package and transport a large (approximately up to 12-feet long and 8-feet high) contaminated object that weighs 35 to 160 tons. Specific characterization results associated with two hot cells, G and H cells will be reported. A review of the activities and plans to stabilize and deactivate the 327 Building provides insight into the technical challenges faced by this project and identifies a potential opportunity to modify the baseline strategy by removing the hot cells in one piece instead of decontaminating and dismantling the cells.

  11. Assessment of sulfur removal processes for advanced fuel cell systems

    SciTech Connect

    Lorton, G.A.

    1980-01-01

    This study consisted of a technical evaluation and economic comparison of sulfur removal processes for integration into a coal gasification-molten carbonate (CGMC) fuel cell power plant. Initially, the performance characteristics of potential sulfur removal processes were evaluated and screened for conformance to the conditions and requirements expected in commercial CGMC power plants. Four of these processes, the Selexol process, the Benfield process, the Sulfinol process, and the Rectisol process, were selected for detailed technical and economic comparison. The process designs were based on a consistent set of technical criteria for a grass roots facility with a capacity of 10,000 tons per day of Illinois No. 6 coal. Two raw gas compositions, based on oxygen-blown and air-blown Texaco gasification, were used. The bulk of the sulfur was removed in the sulfur removal unit, leaving a small amount of sulfur compounds in the gas (1 ppMv or 25 ppMv). The remaining sulfur compounds were removed by reaction with zinc oxide in the sulfur polishing unit. The impact of COS hydrolysis pretreatment on sulfur removal was evaluated. Comprehensive capital and O and M cost estimates for each of the process schemes were developed for the essentially complete removal of sulfur compounds. The impact on the overall plant performance was also determined. The total capital requirement for sulfur removal schemes ranged from $59.4/kW to $84.8/kW for the oxygen-blown cases and from $89.5/kW to $133/kW for the air-blown cases. The O and M costs for sulfur removal for 70% plant capacity factor ranged from 0.82 mills/kWh to 2.76 mills/kWh for the oxygen-blown cases and from 1.77 mills/kWh to 4.88 mills/kWh for the air-blown cases. The Selexol process benefitted the most from the addition of COS hydrolysis pretreatment.

  12. Cell-Specific Aptamers as Emerging Therapeutics

    PubMed Central

    Meyer, Cindy; Hahn, Ulrich; Rentmeister, Andrea

    2011-01-01

    Aptamers are short nucleic acids that bind to defined targets with high affinity and specificity. The first aptamers have been selected about two decades ago by an in vitro process named SELEX (systematic evolution of ligands by exponential enrichment). Since then, numerous aptamers with specificities for a variety of targets from small molecules to proteins or even whole cells have been selected. Their applications range from biosensing and diagnostics to therapy and target-oriented drug delivery. More recently, selections using complex targets such as live cells have become feasible. This paper summarizes progress in cell-SELEX techniques and highlights recent developments, particularly in the field of medically relevant aptamers with a focus on therapeutic and drug-delivery applications. PMID:21904667

  13. Targeting ALDHbright human carcinoma initiating cells with ALDH1A1- specific CD8+ T cells

    PubMed Central

    Visus, Carmen; Wang, Yangyang; Lozano-Leon, Antonio; Ferris, Robert L.; Silver, Susan; Szczepanski, Miroslaw J.; Brand, Randall E.; Ferrone, Cristina R.; Whiteside, Theresa L.; Ferrone, Soldano; DeLeo, Albert B.; Wang, Xinhui

    2011-01-01

    Purpose Tumor cells expressing elevated aldehyde dehydrogenase (ALDH) activity attributed to ALDH1/3 isoforms have been identified as ALDHbright cells and have the properties attributed to cancer initiating cells (CIC). CIC represent the subpopulation of tumor cells that are resistant to conventional cancer treatments and highly tumorigenic in immunodeficient mice. They are considered to be responsible for tumor recurrence and metastasis. The ALDH1A1 isoform was previously identified as a tumor antigen recognized by CD8+ T cells. This study examines the ability of ALDH1A1-specific CD8+ T cells to eliminate ALDHbright cells and control tumor growth and metastases. Experimental Design ALDHbright cells were isolated by flow cytometry from HLA-A2+ human head and neck, breast and pancreas carcinoma cell lines using ALDEFLUOR® and tested for their tumorigenicity in immunodeficient mice. ALDH1A1-specific CD8+ T cells were generated in vitro and tested for their ability to eliminate CIC in vitro and in vivo by adoptive transfer to immunodeficient mice bearing human tumor xenografts. Results ALDHbright cells isolated by flow cytometry from HLA-A2+ breast, head and neck and pancreas carcinoma cell lines at low numbers (500 cells) were tumorigenic in immunodeficient mice. ALDHbright cells present in these cell lines, xenografts or surgically removed lesions were recognized by ALDH1A1-specific CD8+ T cells in vitro. Adoptive therapy with ALDH1A1-specific CD8+ T cells eliminated ALDHbright cells, inhibited tumor growth, metastases or prolonged survival of xenograft-bearing immunodeficient mice. Conclusions The results of this translational study strongly support the potential of ALDH1A1-based immunotherapy to selectively target CIC in human cancer. PMID:21856769

  14. 2,4-Dichlorophenol hydroxylase for chlorophenol removal: Substrate specificity and catalytic activity.

    PubMed

    Ren, Hejun; Li, Qingchao; Zhan, Yang; Fang, Xuexun; Yu, Dahai

    2016-01-01

    Chlorophenols (CPs) are common environmental pollutants. As such, different treatments have been assessed to facilitate their removal. In this study, 2,4-dichlorophenol (2,4-DCP) hydroxylase was used to systematically investigate the activity and removal ability of 19CP congeners at 25 and 0 °C. Results demonstrated that 2,4-DCP hydroxylase exhibited a broad substrate specificity to CPs. The activities of 2,4-DCP hydroxylase against specific CP congeners, including 3-CP, 2,3,6-trichlorophenol, 2-CP, and 2,3-DCP, were higher than those against 2,4-DCP, which is the preferred substrate of previously reported 2,4-DCP hydroxylase. To verify whether cofactors are necessary to promote hydroxylase activity against CP congeners, we added FAD and found that the added FAD induced a 1.33-fold to 5.13-fold significant increase in hydroxylase activity against different CP congeners. The metabolic pathways of the CP degradation in the enzymatic hydroxylation step were preliminarily proposed on the basis of the analyses of the enzymatic activities against 19CP congeners. We found that the high activity and removal rate of 2,4-DCP hydroxylase against CPs at 0 °C enhance the low-temperature-adaptability of this enzyme to the CP congeners; as such, the proposed removal process may be applied to biochemical, bioremediation, and industrial processes, particularly in cold environments. PMID:26672451

  15. Cell Specific eQTL Analysis without Sorting Cells

    PubMed Central

    Esko, Tõnu; Peters, Marjolein J.; Schurmann, Claudia; Schramm, Katharina; Kettunen, Johannes; Yaghootkar, Hanieh; Fairfax, Benjamin P.; Andiappan, Anand Kumar; Li, Yang; Fu, Jingyuan; Karjalainen, Juha; Platteel, Mathieu; Visschedijk, Marijn; Weersma, Rinse K.; Kasela, Silva; Milani, Lili; Tserel, Liina; Peterson, Pärt; Reinmaa, Eva; Hofman, Albert; Uitterlinden, André G.; Rivadeneira, Fernando; Homuth, Georg; Petersmann, Astrid; Lorbeer, Roberto; Prokisch, Holger; Meitinger, Thomas; Herder, Christian; Roden, Michael; Grallert, Harald; Ripatti, Samuli; Perola, Markus; Wood, Andrew R.; Melzer, David; Ferrucci, Luigi; Singleton, Andrew B.; Hernandez, Dena G.; Knight, Julian C.; Melchiotti, Rossella; Lee, Bernett; Poidinger, Michael; Zolezzi, Francesca; Larbi, Anis; Wang, De Yun; van den Berg, Leonard H.; Veldink, Jan H.; Rotzschke, Olaf; Makino, Seiko; Salomaa, Veikko; Strauch, Konstantin; Völker, Uwe; van Meurs, Joyce B. J.; Metspalu, Andres; Wijmenga, Cisca; Jansen, Ritsert C.; Franke, Lude

    2015-01-01

    The functional consequences of trait associated SNPs are often investigated using expression quantitative trait locus (eQTL) mapping. While trait-associated variants may operate in a cell-type specific manner, eQTL datasets for such cell-types may not always be available. We performed a genome-environment interaction (GxE) meta-analysis on data from 5,683 samples to infer the cell type specificity of whole blood cis-eQTLs. We demonstrate that this method is able to predict neutrophil and lymphocyte specific cis-eQTLs and replicate these predictions in independent cell-type specific datasets. Finally, we show that SNPs associated with Crohn’s disease preferentially affect gene expression within neutrophils, including the archetypal NOD2 locus. PMID:25955312

  16. Cell Specific eQTL Analysis without Sorting Cells.

    PubMed

    Westra, Harm-Jan; Arends, Danny; Esko, Tõnu; Peters, Marjolein J; Schurmann, Claudia; Schramm, Katharina; Kettunen, Johannes; Yaghootkar, Hanieh; Fairfax, Benjamin P; Andiappan, Anand Kumar; Li, Yang; Fu, Jingyuan; Karjalainen, Juha; Platteel, Mathieu; Visschedijk, Marijn; Weersma, Rinse K; Kasela, Silva; Milani, Lili; Tserel, Liina; Peterson, Pärt; Reinmaa, Eva; Hofman, Albert; Uitterlinden, André G; Rivadeneira, Fernando; Homuth, Georg; Petersmann, Astrid; Lorbeer, Roberto; Prokisch, Holger; Meitinger, Thomas; Herder, Christian; Roden, Michael; Grallert, Harald; Ripatti, Samuli; Perola, Markus; Wood, Andrew R; Melzer, David; Ferrucci, Luigi; Singleton, Andrew B; Hernandez, Dena G; Knight, Julian C; Melchiotti, Rossella; Lee, Bernett; Poidinger, Michael; Zolezzi, Francesca; Larbi, Anis; Wang, De Yun; van den Berg, Leonard H; Veldink, Jan H; Rotzschke, Olaf; Makino, Seiko; Salomaa, Veikko; Strauch, Konstantin; Völker, Uwe; van Meurs, Joyce B J; Metspalu, Andres; Wijmenga, Cisca; Jansen, Ritsert C; Franke, Lude

    2015-05-01

    The functional consequences of trait associated SNPs are often investigated using expression quantitative trait locus (eQTL) mapping. While trait-associated variants may operate in a cell-type specific manner, eQTL datasets for such cell-types may not always be available. We performed a genome-environment interaction (GxE) meta-analysis on data from 5,683 samples to infer the cell type specificity of whole blood cis-eQTLs. We demonstrate that this method is able to predict neutrophil and lymphocyte specific cis-eQTLs and replicate these predictions in independent cell-type specific datasets. Finally, we show that SNPs associated with Crohn's disease preferentially affect gene expression within neutrophils, including the archetypal NOD2 locus. PMID:25955312

  17. Copper cation removal in an electrokinetic cell containing zeolite.

    PubMed

    Elsayed-Ali, Omar H; Abdel-Fattah, Tarek; Elsayed-Ali, Hani E

    2011-01-30

    Zeolites are used in environmental remediation of soil or water to immobilize or remove toxic materials by cation exchange. An experiment was conducted to test the use a low electric field to direct the toxic cations towards the zeolite. An electrokinetic cell was constructed using carbon electrodes. Synthetic Linde Type A (LTA) zeolite was placed in the cell. Copper(II) chloride dissolved in water was used as a contaminant. The Cu(2+) concentration was measured for ten hours with and without an applied electric field. The removal of the Cu(2+) ions was accelerated by the applied field in the first two hours. For longer time, the electric field did not improve the removal rate of the Cu(2+) ions. The presence of zeolite and applied electric field complicates the chemistry near the cathode and causes precipitation of Cu(2+) ions as copper oxide on the surface of the zeolite. With increased electric field the zeolite farther away from the cathode had little cation exchange due to the higher drift velocity of the Cu(2+) ions. The results also show that, in the LTA Zeolite A pellets, the cation exchange of Cu is limited to a shell of several tens of micrometers. PMID:21109348

  18. The effect of fat removal on glucose tolerance is depot specific in male and female mice.

    PubMed

    Shi, Haifei; Strader, April D; Woods, Stephen C; Seeley, Randy J

    2007-10-01

    Energy is stored predominately as lipid in white adipose tissue (WAT) in distinct anatomical locations, with each site exerting different effects on key biological processes, including glucose homeostasis. To determine the relative contributions of subcutaneous and visceral WAT on glucose homeostasis, comparable amounts of adipose tissue from abdominal subcutaneous inguinal WAT (IWAT), intra-abdominal retroperitoneal WAT (RWAT), male gonadal epididymal WAT (EWAT), or female gonadal parametrial WAT (PWAT) were removed. Gonadal fat removal in both male and female chow-fed lean mice resulted in lowered glucose levels across glucose tolerance tests. Female lean C57BL/6J mice as well as male and female lean FVBN mice significantly improved glucose tolerance, indicated by decreased areas under glucose clearance curves. For the C57BL/6J mice maintained on a high-fat butter-based diet, glucose homeostasis was improved only in female mice with PWAT removal. Removal of IWAT or RWAT did not affect glucose tolerance in either dietary condition. We conclude that WAT contribution to glucose homeostasis is depot specific, with male gonadal EWAT contributing to glucose homeostasis in the lean state, whereas female gonadal PWAT contributes to glucose homeostasis in both lean and obese mice. These data illustrate both critical differences among various WAT depots and how they influence glucose homeostasis and highlight important differences between males and females in glucose regulation. PMID:17652151

  19. Typical low cost biosorbents for adsorptive removal of specific organic pollutants from water.

    PubMed

    Tran, Van Son; Ngo, Huu Hao; Guo, Wenshan; Zhang, Jian; Liang, Shuang; Ton-That, Cuong; Zhang, Xinbo

    2015-04-01

    Specific organic pollutants (SOPs) such as phenolic compounds, PAHs, organic pesticides, and organic herbicides cause health and environmental problems due to their excessive toxic properties and poor biodegradability. Low-cost biosorbents are considered as a promising alternative for conventional adsorbents to remove SOPs from water. These materials have several advantages such as high sorption capacities, good modifiability and recoverability, insensitivity to toxic substances, simple operation in the treatment processes. However, previous reports on various types of biosorbents for removing SOPs are still moderately fragmented. Hence, this paper provides a comprehensive review on using typical low-cost biosorbents obtained from lignocellulose and chitin/chitosan for SOPs adsorption. Especially, their characteristics, biosorption mechanism together with utilization for eliminating SOPs are presented and discussed. The paper also gives a critical view regarding future applications of low-cost biosorbents in SOPs-contaminated water treatment. PMID:25690682

  20. Cell therapy to remove excess copper in Wilson's disease.

    PubMed

    Gupta, Sanjeev

    2014-05-01

    To achieve permanent correction of Wilson's disease by a cell therapy approach, replacement of diseased hepatocytes with healthy hepatocytes is desirable. There is a physiological requirement for hepatic ATP7B-dependent copper (Cu) transport in bile, which is deficient in Wilson's disease, producing progressive Cu accumulation in the liver or brain with organ damage. The ability to repopulate the liver with healthy hepatocytes raises the possibility of cell therapy in Wilson's disease. Therapeutic principles included reconstitution of bile canalicular network as well as proliferation in transplanted hepatocytes, despite toxic amounts of Cu in the liver. Nonetheless, cell therapy studies in animal models elicited major differences in the mechanisms driving liver repopulation with transplanted hepatocytes in Wilson's disease versus nondiseased settings. Recently, noninvasive imaging was developed to demonstrate Cu removal from the liver, including after cell therapy in Wilson's disease. Such developments will help advance cell/gene therapy approaches, particularly by offering roadmaps for clinical trials in people with Wilson's disease. PMID:24820353

  1. Imaging Specific Genomic DNA in Living Cells.

    PubMed

    Chen, Baohui; Guan, Juan; Huang, Bo

    2016-07-01

    The three-dimensional organization of the genome plays important roles in regulating the functional output of the genome and even in the maintenance of epigenetic inheritance and genome stability. Here, we review and compare a number of newly developed methods-especially those that utilize the CRISPR (clustered regularly interspaced short palindromic repeat)-Cas9 (CRISPR-associated protein 9) system-that enable the direct visualization of specific, endogenous DNA sequences in living cells. We also discuss the practical considerations in implementing the CRISPR imaging technique to achieve sufficient signal-to-background levels, high specificity, and high labeling efficiency. These DNA labeling methods enable tracking of the copy number, localization, and movement of genomic elements, and we discuss the potential applications of these methods in understanding the searching and targeting mechanism of the Cas9-sgRNA complex, investigating chromosome organization, and visualizing genome instability and rearrangement. PMID:27145877

  2. Material Removal and Specific Energy in the Dynamic Scratching of Gamma Titanium Aluminides

    SciTech Connect

    Wang, Hong; Lin, Hua-Tay; Wereszczak, Andrew A

    2006-11-01

    Mechanical responses of three gamma titanium aluminides (TiAls) (denoted as Alloy A, Alloy B and Alloy C) subjected to dynamic scratching were studied by using a single-grit pendulum (rotating) scratch tester. The maximum depth of groove was ~ 0.07 mm, and the scratch velocity used was ~ 1.0 m/s. Normal and tangential forces were monitored. The material removal mechanisms were examined using a scanning electron microscope (SEM) and the scratches were measured by using a laser profilometer. The mechanical properties of the tested TiAls were characterized by the instantaneous specific energy, scratch resistance and scratch hardness as related to the depth of groove. Extensive thermal softening was observed in the dynamic scratch of the tested TiAls, which facilitated both the detachments of developing chips and the pile-ups of materials on side ridges. Sizable fractures were observed in the transverse direction on the tested TiAls; these fractures tended to participate in the chip formation, depending on the microstructure of the TiAl and the size of the scratch groove. Specific energy and scratch hardness are depth-dependent to various degrees for the tested TiAls. The materiel removal might be subjected to different mechanisms, but the overall response of materials can be effectively characterized by the HEM (Hwang, Evans and Malkin) model and the PSR (proportional specimen resistance) model. The obtained depth-independent specific energy and scratch hardness can be used to screen the candidate materials for the specific purpose depending on whether the application is scratch-dominant or impact-dominant. Among the three tested TiAls, the TiAl with larger colony or grain size exhibits a stronger capability of energy dissipation in the material loss or material removal (higher depth-independent specific energy), while the TiAl with smaller colony size show a higher resistance against the indentation (higher depth-independent scratch hardness). The observations and

  3. Cell-Specific Cardiac Electrophysiology Models

    PubMed Central

    Groenendaal, Willemijn; Ortega, Francis A.; Kherlopian, Armen R.; Zygmunt, Andrew C.; Krogh-Madsen, Trine; Christini, David J.

    2015-01-01

    The traditional cardiac model-building paradigm involves constructing a composite model using data collected from many cells. Equations are derived for each relevant cellular component (e.g., ion channel, exchanger) independently. After the equations for all components are combined to form the composite model, a subset of parameters is tuned, often arbitrarily and by hand, until the model output matches a target objective, such as an action potential. Unfortunately, such models often fail to accurately simulate behavior that is dynamically dissimilar (e.g., arrhythmia) to the simple target objective to which the model was fit. In this study, we develop a new approach in which data are collected via a series of complex electrophysiology protocols from single cardiac myocytes and then used to tune model parameters via a parallel fitting method known as a genetic algorithm (GA). The dynamical complexity of the electrophysiological data, which can only be fit by an automated method such as a GA, leads to more accurately parameterized models that can simulate rich cardiac dynamics. The feasibility of the method is first validated computationally, after which it is used to develop models of isolated guinea pig ventricular myocytes that simulate the electrophysiological dynamics significantly better than does a standard guinea pig model. In addition to improving model fidelity generally, this approach can be used to generate a cell-specific model. By so doing, the approach may be useful in applications ranging from studying the implications of cell-to-cell variability to the prediction of intersubject differences in response to pharmacological treatment. PMID:25928268

  4. Material Removal and Specific Energy in the Dynamic Scratching of Gamma Titanium Aluminides

    SciTech Connect

    Wang, H.; Lin, H.-T.; Wereszczak, A.A.

    2006-11-30

    Mechanical responses of three gamma titanium aluminides (TiAls) (denoted as Alloy A, Alloy B and Alloy C) subjected to dynamic scratching were studied by using a single-grit pendulum (rotating) scratch tester. The maximum depth of groove was {approx} 0.07 mm, and the scratch velocity was {approx} 1.0 m/s. Normal and tangential forces were monitored. The material removal mechanisms were examined using a scanning electron microscope (SEM) and the scratches were measured by using a laser profilometer. The mechanical properties of the tested TiAls were characterized by the instantaneous specific energy, scratch resistance and scratch hardness as related to the groove depth. Extensive thermal softening was observed in the dynamic scratch test of the TiAls, which facilitated both the detachment of developing chips and pile-up of material on side ridges. Sizable fractures were observed in the transverse direction in the tested TiAls; these fractures tended to participate in the chip formation, depending on the microstructure of the TiAl and the size of the scratch groove. Specific energy and scratch hardness are depth-dependent to various degrees for the TiAls tested. The material removal might be subjected to different mechanisms, but the overall material response can be effectively characterized by the HEM (Hwang, Evans and Malkin) model and the PSR (proportional specimen resistance) model. The depth-independent specific energy and scratch hardness can be used to screen candidate materials for the applications that are scratch-dominated versus impact-dominated. Among the three tested TiAls, the TiAl with larger colony or grain size exhibits a stronger capability of energy dissipation during material removal (higher depth-independent specific energy), while the TiAl with smaller colony size shows a higher resistance to indentation (higher depth-independent scratch hardness). The observations and conclusions in this study can serve as a base line for the further

  5. Removal of sulfur contaminants in methanol for fuel cell applications

    SciTech Connect

    Lee, S.H.D.; Kumar, R.; Sederquist, R.

    1996-12-31

    Equilibrium adsorption isotherm and breakthrough data were used to assess feasibility of developing a granular activated carbon (GAC) adsorber for use as a sulfur removal subsystem in transportation fuel cell systems. Results suggest that an on-board GAC adsorber may not be attractive due to size and weight constraints. However, it may be feasible to install this GAC adsorber at methanol distribution stations, where space and weight are not a critical concern. Preliminary economic analysis indicated that the GAC adsorber concept will be attractive if the spent AC can be regenerated for reuse. These preliminary analyses were made on basis of very limited breakthrough data obtained from the bench-scale testing. Optimization on dynamic testing parameters and study on regeneration of spent AC are needed.

  6. Cell-specific analysis of tracheobronchial secretory cells and secretions

    SciTech Connect

    Finkbeiner, W.E.

    1989-01-01

    In these studies, two methods (cell culture and monoclonal antibody production) that allowed cell-specific analysis of tracheobronchial secretion were used. Bovine tracheal submucosal gland cells were isolated, placed into culture and serially propagated. In culture, the cells maintained features of serous cells. The cells incorporated {sup 35}S into high molecular weight molecules. {beta}-adrenergic agonists stimulated release of radiolabeled molecules and elevations in intracellular cAMP levels, responses that could be blocked by the {beta}-adrenergic antagonist propranolol. Cyclic AMP appeared to be involved in the stimulus-secretion coupling events in serous cells since the phosphodiesterase inhibitor 1-methyl-3-isobutylxanthine potentiated the effects of isoproterenol on the secretory response and the elevation of intracellular cAMP levels. Furthermore, cAMP analogues elicited a secretory response in the absence of cAMP. The phosphorylation state of several cytosolic and particulate phosphoproteins was altered by cAMP-activated kinase activity. Monoclonal antibodies were produced against human airway secretions.

  7. Facial dermis grafts after removal of basal cell carcinomas.

    PubMed

    Han, Seung-Kyu; Yoon, Won-Young; Jeong, Seong-Ho; Kim, Woo-Kyung

    2012-11-01

    Selecting a proper reconstruction method is the key to success in skin cancer management, especially for lesions involving the face. Using a skin graft is usually straightforward when covering a skin defect; however, major concerns in skin grafting include a poor color match in the recipient-site and donor-site morbidity. To overcome these limitations, the authors have developed a dermis graft, which utilizes a de-epithelialized split-thickness skin graft method. The purpose of this retrospective study was to report reliability of dermis grafts after removal of basal cell carcinomas (BCCs) on the face by presenting our clinical experience with them. This study included 38 patients who were treated for facial defects created by resection of BCCs. The locations of the defects were as follows: nose (n = 17), orbital area (n = 14), cheek (n = 4), temple area (n = 2), and forehead (n = 1). The defects ranged in size from 3.3 to 6.5 cm. Functional and cosmetic outcomes, postoperative complications, and patient satisfaction were assessed. The patients were followed up for 12 to 36 months. The entire dermis graft re-epithelialized after grafting within 17 to 27 days. Most of the patients had satisfactory results in both functional and cosmetic matters with high-quality skin characteristics. There were no significant complications and no recurrences were observed during the follow-up period. Patient satisfaction with the dermis graft was also excellent. The dermis graft may be used reliably for covering defects after removal of BCCs on the face. PMID:23172436

  8. Induction of type I IFN is required for overcoming tumor-specific T-cell tolerance after stem cell transplantation.

    PubMed

    Horkheimer, Ian; Quigley, Michael; Zhu, Jiangao; Huang, Xiaopei; Chao, Nelson J; Yang, Yiping

    2009-05-21

    Tumor-specific T-cell tolerance represents one major mechanism of tumor-induced immune evasion. Myeloablative chemotherapy with stem cell transplantation may offer the best chance of achieving a state of minimal residual disease and, thus, minimize tumor-induced immune evasion. However, studies have shown that tumor-specific T-cell tolerance persists after transplantation. Here, we showed that CD4(+)CD25(+) regulatory T (T(Reg)) cells play a critical role in tumor-specific CD8(+) T-cell tolerance after transplantation. Removal of T(Reg) cells from the donor lymphocyte graft did not overcome this tolerance because of rapid conversion of donor CD4(+)CD25(-) T cells into CD4(+)CD25(+)Foxp3(+) T(Reg) cells in recipients after transplantation, and depletion of T(Reg) cells in recipients was necessary for the reversal of tumor-specific tolerance. These results suggest that strategies capable of overcoming T-cell tolerance in recipients are required to promote antitumor immunity after transplantation. Toward this goal, we showed that dendritic cell (DC) vaccines coadministered with the TLR9 ligand, CpG could effectively overcome tumor-specific tolerance, leading to significant prolongation of tumor-free survival after transplantation. We further showed that CpG-induced type I interferon was critical for the reversal of tumor-specific tolerance in vivo. Collectively, these results may suggest effective immunotherapeutic strategies for treating cancer after stem cell transplantation. PMID:19279333

  9. Development of standardized specifications for silicon solar cells

    NASA Technical Reports Server (NTRS)

    Scott-Monck, J. A.

    1977-01-01

    A space silicon solar cell assembly (cell and coverglass) specification aimed at standardizing the diverse requirements of current cell or assembly specifications was developed. This specification was designed to minimize both the procurement and manufacturing costs for space qualified silicon solar cell assembilies. In addition, an impact analysis estimating the technological and economic effects of employing a standardized space silicon solar cell assembly was performed.

  10. Cell-specific transmembrane injection of molecular cargo with gold nanoparticle-generated transient plasmonic nanobubbles.

    PubMed

    Lukianova-Hleb, Ekaterina Y; Wagner, Daniel S; Brenner, Malcolm K; Lapotko, Dmitri O

    2012-07-01

    Optimal cell therapies require efficient, selective and rapid delivery of molecular cargo into target cells without compromising their viability. Achieving these goals ex vivo in bulk heterogeneous multi-cell systems such as human grafts is impeded by low selectivity and speed of cargo delivery and by significant damage to target and non-target cells. We have developed a cell level approach for selective and guided transmembrane injection of extracellular cargo into specific target cells using transient plasmonic nanobubbles (PNB) as cell-specific nano-injectors. As a technical platform for this method we developed a laser flow cell processing system. The PNB injection method and flow system were tested in heterogeneous cell suspensions of target and non-target cells for delivery of Dextran-FITC dye into squamous cell carcinoma HN31 cells and transfection of human T-cells with a green fluorescent protein-encoding plasmid. In both models the method demonstrated single cell type selectivity, high efficacy of delivery (96% both for HN31 cells T-cells), speed of delivery (nanoseconds) and viability of treated target cells (96% for HN31 cells and 75% for T-cells). The PNB injection method may therefore be beneficial for real time processing of human grafts without removal of physiologically important cells. PMID:22521612

  11. Dermis mechanical behaviour after different cell removal treatments.

    PubMed

    Terzini, Mara; Bignardi, Cristina; Castagnoli, Carlotta; Cambieri, Irene; Zanetti, Elisabetta M; Audenino, Alberto L

    2016-09-01

    Human acellular dermal matrices (HADMs) are used in reconstructive surgery as scaffolds promoting autologous tissue regeneration. Critical to the HADM ability to remodel and integrate into the host tissue is the removal of cells while maintaining an intact extracellular architecture. The objective of this work is to develop a methodology to analyse the mechanical properties of HADMs after decellularization to identify its ideal form of treatment and its duration. Two different decellularization techniques were used as a benchmark: the first is a well-established technique (incubation in NaOH for 1-7 weeks), and the second is an innovative technique developed by this research group (incubation in DMEM (Dulbecco's modified Eagle medium) for 1-7 weeks). After decellularization, the specimens underwent uniaxial tensile tests, and experimental data were represented with stress strain curves, calculating both engineering and true values. Mechanical tests have led to the identification of the optimal method (NaOH or DMEM) and duration for the decellularization treatment; differences between engineering and true values can reach 84%, but the engineering values remain useful to make comparisons, providing reliable indications with a simpler experimental set up and data processing. PMID:26997564

  12. Cell-Specific Promoters Enable Lipid-Based Nanoparticles to Deliver Genes to Specific Cells of the Retina In Vivo

    PubMed Central

    Wang, Yuhong; Rajala, Ammaji; Cao, Binrui; Ranjo-Bishop, Michelle; Agbaga, Martin-Paul; Mao, Chuanbin; Rajala, Raju V.S.

    2016-01-01

    Non-viral vectors, such as lipid-based nanoparticles (liposome-protamine-DNA complex [LPD]), could be used to deliver a functional gene to the retina to correct visual function and treat blindness. However, one of the limitations of LPD is the lack of cell specificity, as the retina is composed of seven types of cells. If the same gene is expressed in multiple cell types or is absent from one desired cell type, LPD-mediated gene delivery to every cell may have off-target effects. To circumvent this problem, we have tested LPD-mediated gene delivery using various generalized, modified, and retinal cell-specific promoters. We achieved retinal pigment epithelium cell specificity with vitelliform macular dystrophy (VMD2), rod cell specificity with mouse rhodopsin, cone cell specificity with red/green opsin, and ganglion cell specificity with thymocyte antigen promoters. Here we show for the first time that cell-specific promoters enable lipid-based nanoparticles to deliver genes to specific cells of the retina in vivo. This work will inspire investigators in the field of lipid nanotechnology to couple cell-specific promoters to drive expression in a cell- and tissue-specific manner. PMID:27446487

  13. Automated Cell Enrichment of Cytomegalovirus-specific T cells for Clinical Applications using the Cytokine-capture System.

    PubMed

    Kumaresan, Pappanaicken; Figliola, Mathew; Moyes, Judy S; Huls, M Helen; Tewari, Priti; Shpall, Elizabeth J; Champlin, Richard; Cooper, Laurence J N

    2015-01-01

    The adoptive transfer of pathogen-specific T cells can be used to prevent and treat opportunistic infections such as cytomegalovirus (CMV) infection occurring after allogeneic hematopoietic stem-cell transplantation. Viral-specific T cells from allogeneic donors, including third party donors, can be propagated ex vivo in compliance with current good manufacturing practice (cGMP), employing repeated rounds of antigen-driven stimulation to selectively propagate desired T cells. The identification and isolation of antigen-specific T cells can also be undertaken based upon the cytokine capture system of T cells that have been activated to secrete gamma-interferon (IFN-γ). However, widespread human application of the cytokine capture system (CCS) to help restore immunity has been limited as the production process is time-consuming and requires a skilled operator. The development of a second-generation cell enrichment device such as CliniMACS Prodigy now enables investigators to generate viral-specific T cells using an automated, less labor-intensive system. This device separates magnetically labeled cells from unlabeled cells using magnetic activated cell sorting technology to generate clinical-grade products, is engineered as a closed system and can be accessed and operated on the benchtop. We demonstrate the operation of this new automated cell enrichment device to manufacture CMV pp65-specific T cells obtained from a steady-state apheresis product obtained from a CMV seropositive donor. These isolated T cells can then be directly infused into a patient under institutional and federal regulatory supervision. All the bio-processing steps including removal of red blood cells, stimulation of T cells, separation of antigen-specific T cells, purification, and washing are fully automated. Devices such as this raise the possibility that T cells for human application can be manufactured outside of dedicated good manufacturing practice (GMP) facilities and instead be produced

  14. Method of improving fuel cell performance by removing at least one metal oxide contaminant from a fuel cell electrode

    DOEpatents

    Kim, Yu Seung; Choi, Jong-Ho; Zelenay, Piotr

    2009-08-18

    A method of removing contaminants from a fuel cell catalyst electrode. The method includes providing a getter electrode and a fuel cell catalyst electrode having at least one contaminant to a bath and applying a voltage sufficient to drive the contaminant from the fuel cell catalyst electrode to the getter electrode. Methods of removing contaminants from a membrane electrode assembly of a fuel cell and of improving performance of a fuel cell are also provided.

  15. Specific cell cycle synchronization with butyrate and cell cycle analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synchronized cells have been invaluable for many kinds of cell cycle and cell proliferation studies. Butyrate induces cell cycle arrest and apoptosis in MDBK cells. To explore the possibility of using butyrate-blocked cells to obtain synchronized cells, we investigated the property of the cell cyc...

  16. Assessment of sulfur removal processes for advanced fuel cell systems

    NASA Astrophysics Data System (ADS)

    Lorton, G. A.

    1980-01-01

    The performance characteristics of potential sulfur removal processes were evaluated and four of these processes, the Selexol process, the Benfield process, the Sulfinol process, and the Rectisol process, were selected for detailed technical and economic comparison. The process designs were based on a consistent set of technical criteria for a grass roots facility with a capacity of 10,000 tons per day of Illinois No. 6 coal. Two raw gas compositions, based on oxygen blown and air blown Texaco gasification, were used. The bulk of the sulfur was removed in the sulfur removal unit, leaving a small amount of sulfur compounds in the gas. The remaining sulfur compounds were removed by reaction with zinc oxide in the sulfur polishing unit. The impact of COS hydrolysis pretreatment on sulfur removal was evaluated. Comprehensive capital and O and M cost estimates for each of the process schemes were developed.

  17. Skin Biopsy and Patient-Specific Stem Cell Lines

    PubMed Central

    Li, Yao; Nguyen, Huy V.; Tsang, Stephen H.

    2016-01-01

    The generation of patient-specific induced pluripotent stem (iPS) cells permits the development of next-generation patient-specific systems biology models reflecting personalized genomics profiles to better understand pathophysiology. In this chapter, we describe how to create a patient-specific iPS cell line. There are three major steps: (1) performing a skin biopsy procedure on the patient; (2) extracting human fibroblast cells from the skin biopsy tissue; and (3) reprogramming patient-specific fibroblast cells into the pluripotent stem cell stage. PMID:26141312

  18. Solid oxide fuel cell generator with removable modular fuel cell stack configurations

    DOEpatents

    Gillett, J.E.; Dederer, J.T.; Zafred, P.R.; Collie, J.C.

    1998-04-21

    A high temperature solid oxide fuel cell generator produces electrical power from oxidation of hydrocarbon fuel gases such as natural gas, or conditioned fuel gases, such as carbon monoxide or hydrogen, with oxidant gases, such as air or oxygen. This electrochemical reaction occurs in a plurality of electrically connected solid oxide fuel cells bundled and arrayed in a unitary modular fuel cell stack disposed in a compartment in the generator container. The use of a unitary modular fuel cell stack in a generator is similar in concept to that of a removable battery. The fuel cell stack is provided in a pre-assembled self-supporting configuration where the fuel cells are mounted to a common structural base having surrounding side walls defining a chamber. Associated generator equipment may also be mounted to the fuel cell stack configuration to be integral therewith, such as a fuel and oxidant supply and distribution systems, fuel reformation systems, fuel cell support systems, combustion, exhaust and spent fuel recirculation systems, and the like. The pre-assembled self-supporting fuel cell stack arrangement allows for easier assembly, installation, maintenance, better structural support and longer life of the fuel cells contained in the fuel cell stack. 8 figs.

  19. Solid oxide fuel cell generator with removable modular fuel cell stack configurations

    DOEpatents

    Gillett, James E.; Dederer, Jeffrey T.; Zafred, Paolo R.; Collie, Jeffrey C.

    1998-01-01

    A high temperature solid oxide fuel cell generator produces electrical power from oxidation of hydrocarbon fuel gases such as natural gas, or conditioned fuel gases, such as carbon monoxide or hydrogen, with oxidant gases, such as air or oxygen. This electrochemical reaction occurs in a plurality of electrically connected solid oxide fuel cells bundled and arrayed in a unitary modular fuel cell stack disposed in a compartment in the generator container. The use of a unitary modular fuel cell stack in a generator is similar in concept to that of a removable battery. The fuel cell stack is provided in a pre-assembled self-supporting configuration where the fuel cells are mounted to a common structural base having surrounding side walls defining a chamber. Associated generator equipment may also be mounted to the fuel cell stack configuration to be integral therewith, such as a fuel and oxidant supply and distribution systems, fuel reformation systems, fuel cell support systems, combustion, exhaust and spent fuel recirculation systems, and the like. The pre-assembled self-supporting fuel cell stack arrangement allows for easier assembly, installation, maintenance, better structural support and longer life of the fuel cells contained in the fuel cell stack.

  20. Tolerance induction in memory CD4 T cells requires two rounds of antigen-specific activation.

    PubMed

    David, Alexandria; Crawford, Frances; Garside, Paul; Kappler, John W; Marrack, Philippa; MacLeod, Megan

    2014-05-27

    A major goal for immunotherapy is to tolerize the immune cells that coordinate tissue damage in autoimmune and alloantigen responses. CD4 T cells play a central role in many of these conditions and improved antigen-specific regulation or removal of these cells could revolutionize current treatments. A confounding factor is that little is known about whether and how tolerance is induced in memory CD4 T cells. We used MHC class II tetramers to track and analyze a population of endogenous antigen-specific memory CD4 T cells exposed to soluble peptide in the absence of adjuvant. We found that such memory T cells proliferated and reentered the memory pool apparently unperturbed by the incomplete activation signals provided by the peptide. Upon further restimulation in vivo, CD4 memory T cells that had been previously exposed to peptide proliferated, provided help to primary responding B cells, and migrated to inflamed sites. However, these reactivated memory cells failed to survive. The reduction in T-cell number was marked by low expression of the antiapoptotic molecule B cell lymphoma 2 (Bcl2) and increased expression of activated caspase molecules. Consequently, these cells failed to sustain a delayed-type hypersensitivity response. Moreover, following two separate exposures to soluble antigen, no T-cell recall response and no helper activity for B cells could be detected. These results suggest that the induction of tolerance in memory CD4 T cells is possible but that deletion and permanent removal of the antigen-specific T cells requires reactivation following exposure to the tolerogenic antigen. PMID:24821788

  1. Enteric glial cells have specific immunosuppressive properties.

    PubMed

    Kermarrec, Laetitia; Durand, Tony; Neunlist, Michel; Naveilhan, Philippe; Neveu, Isabelle

    2016-06-15

    Enteric glial cells (EGC) have trophic and neuroregulatory functions in the enteric nervous system, but whether they exert a direct effect on immune cells is unknown. Here, we used co-cultures to show that human EGC can inhibit the proliferation of activated T lymphocytes. Interestingly, EGC from Crohn's patients were effective at one EGC for two T cells whereas EGC from control patients required a ratio of 1:1. These data suggest that EGC contribute to local immune homeostasis in the gastrointestinal wall. They also raise the possibility that EGC have particular immunosuppressive properties in inflammatory bowel diseases such as Crohn's disease. PMID:27235353

  2. Habitat-specific nutrient removal and release in Oregon salt marshes

    EPA Science Inventory

    Wetlands can be sources, sinks and transformers of nutrients, although it is their role in nutrient removal that is valued as a water purification ecosystem service. In order to quantify that service for any wetland, it is important to understand the drivers of nutrient removal w...

  3. Cell-specific nitrogen responses mediate developmental plasticity

    PubMed Central

    Gifford, Miriam L.; Dean, Alexis; Gutierrez, Rodrigo A.; Coruzzi, Gloria M.; Birnbaum, Kenneth D.

    2008-01-01

    The organs of multicellular species consist of cell types that must function together to perform specific tasks. One critical organ function is responding to internal or external change. Some cell-specific responses to changes in environmental conditions are known, but the scale of cell-specific responses within an entire organ as it perceives an environmental flux has not been well characterized in plants or any other multicellular organism. Here, we use cellular profiling of five Arabidopsis root cell types in response to an influx of a critical resource, nitrogen, to uncover a vast and predominantly cell-specific response. We show that cell-specific profiling increases sensitivity several-fold, revealing highly localized regulation of transcripts that were largely hidden from previous global analyses. The cell-specific data revealed responses that suggested a coordinated developmental response in distinct cell types or tissues. One example is the cell-specific regulation of a transcriptional circuit that we showed mediates lateral root outgrowth in response to nitrogen via microRNA167, linking small RNAs to nitrogen responses. Together, these results reveal a previously cryptic component of cell-specific responses to nitrogen. Thus, the results make an important advance in our understanding of how multicellular organisms cope with environmental change at the cell level. PMID:18180456

  4. Induction of tissue-specific stem cells by reprogramming factors, and tissue-specific selection.

    PubMed

    Noguchi, H; Saitoh, I; Tsugata, T; Kataoka, H; Watanabe, M; Noguchi, Y

    2015-01-01

    Although induced pluripotent stem (iPS) cells have significant implications for overcoming most of the ethical issues associated with embryonic stem (ES) cells, there are still several unresolved issues related to the use of iPS cells for clinical applications, such as teratoma formation. In this study, we were able to generate tissue-specific stem (induced tissue-specific stem; iTS) cells from the pancreas (iTS-P) or liver (iTS-L) by transient overexpression of reprogramming factors, combined with tissue-specific selection. The generation of iTS cells was easier than that of iPS cells. The iTS-P/iTS-L cells express genetic markers of endoderm and pancreatic/hepatic progenitors and were able to differentiate into insulin-producing cells/hepatocytes more efficiently than ES cells. Subcutaneous transplantation of both types of iTS cells into immunodeficient mice resulted in no teratoma formation. The technology used for the transient overexpression of reprogramming factors and tissue-specific selection may be useful for the generation of other tissue-specific stem cells, and the generation of iTS cells could have important implications for the clinical application of stem cells. PMID:25190146

  5. Induction of tissue-specific stem cells by reprogramming factors, and tissue-specific selection

    PubMed Central

    Noguchi, H; Saitoh, I; Tsugata, T; Kataoka, H; Watanabe, M; Noguchi, Y

    2015-01-01

    Although induced pluripotent stem (iPS) cells have significant implications for overcoming most of the ethical issues associated with embryonic stem (ES) cells, there are still several unresolved issues related to the use of iPS cells for clinical applications, such as teratoma formation. In this study, we were able to generate tissue-specific stem (induced tissue-specific stem; iTS) cells from the pancreas (iTS-P) or liver (iTS-L) by transient overexpression of reprogramming factors, combined with tissue-specific selection. The generation of iTS cells was easier than that of iPS cells. The iTS-P/iTS-L cells express genetic markers of endoderm and pancreatic/hepatic progenitors and were able to differentiate into insulin-producing cells/hepatocytes more efficiently than ES cells. Subcutaneous transplantation of both types of iTS cells into immunodeficient mice resulted in no teratoma formation. The technology used for the transient overexpression of reprogramming factors and tissue-specific selection may be useful for the generation of other tissue-specific stem cells, and the generation of iTS cells could have important implications for the clinical application of stem cells. PMID:25190146

  6. Xeroderma pigmentosum complementation group C cells remove pyrimidine dimers selectively from the transcribed strand of active genes

    SciTech Connect

    Venema, J.; van Hoffen, A.; Karcagi, V.; Natarajan, A.T.; van Zeeland, A.A.; Mullenders, L.H. )

    1991-08-01

    The authors have measured the removal of UV-induced pyrimidine dimers from DNA fragments of the adenosine deaminase (ADA) and dihydrofolate reductase (DHFR) genes in primary normal human and xeroderma pigmentosum complementation group C (XP-C) cells. Using strand-specific probes, we show that in normal cells, preferential repair of the 5{prime} part of the ADA gene is due to the rapid and efficient repair of the transcribed strand. Within 8 h after irradiation with UV at 10 J m-2, 70% of the pyrimidine dimers in this strand are removed. The nontranscribed strand is repaired at a much slower rate, with 30% dimers removed after 8 h. Repair of the transcribed strand in XP-C cells occurs at a rate indistinguishable from that in normal cells, but the nontranscribed strand is not repaired significantly in these cells. Similar results were obtained for the DHFR gene. In the 3{prime} part of the ADA gene, however, both normal and XP-C cells perform fast and efficient repair of either strand, which is likely to be caused by the presence of transcription units on both strands. The factor defective in XP-C cells is apparently involved in the processing of DNA damage in inactive parts of the genome, including nontranscribed strands of active genes. These findings have important implications for the understanding of the mechanism of UV-induced excision repair and mutagenesis in mammalian cells.

  7. Flexible Octopus-Shaped Hydrogel Particles for Specific Cell Capture.

    PubMed

    Chen, Lynna; An, Harry Z; Haghgooie, Ramin; Shank, Aaron T; Martel, Joseph M; Toner, Mehmet; Doyle, Patrick S

    2016-04-01

    Multiarm hydrogel microparticles with varying geometry are fabricated to specifically capture cells expressing epithelial cell adhesion molecule. Results show that particle shape influences cell-capture efficiency due to differences in surface area, hydrodynamic effects, and steric constraints. These findings can lead to improved particle design for cell separation and diagnostic applications. PMID:26929053

  8. Method for removal of metal atoms from aqueous solution using suspended plant cells

    DOEpatents

    Jackson, Paul J.; Torres, deceased, Agapito P.; Delhaize, Emmanuel

    1992-01-01

    The use of plant suspension cultures to remove ionic metallic species and TNT-based explosives and their oxidation products from aqueous solution is described. Several plant strains were investigated including D. innoxia, Citrus citrus, and Black Mexican Sweet Corn. All showed significant ability to remove metal ions. Ions removed to sub-ppm levels include barium, iron, and plutonium. D. innoxia cells growing in media containing weapons effluent contaminated with Ba.sup.2+ also remove TNT, other explosives and oxidation products thereof from solution. The use of dead, dehydrated cells were also found to be of use in treating waste directly.

  9. Method for removal of explosives from aqueous solution using suspended plant cells

    DOEpatents

    Jackson, Paul J.; Torres, deceased, Agapito P.; Delhaize, Emmanuel

    1994-01-01

    The use of plant suspension cultures to remove ionic metallic species and TNT-based explosives and their oxidation products from aqueous solution is described. Several plant strains were investigated including D. innoxia, Citrus citrus, and Black Mexican Sweet Corn. All showed significant ability to remove metal ions. Ions removed to sub-ppm levels include barium, iron, and plutonium. D. innoxia cells growing in media containing weapons effluent contaminated with Ba.sup.2+ also remove TNT, other explosives and oxidation products thereof from solution. The use of dead, dehydrated cells was also found to be of use in treating waste directly.

  10. Allergen-Specific CD4(+) T Cells in Human Asthma.

    PubMed

    Ling, Morris F; Luster, Andrew D

    2016-03-01

    In allergic asthma, aeroallergen exposure of sensitized individuals mobilizes robust innate and adaptive airway immune responses, stimulating eosinophilic airway inflammation and the activation and infiltration of allergen-specific CD4(+) T cells into the airways. Allergen-specific CD4(+) T cells are thought to be central players in the asthmatic response as they specifically recognize the allergen and initiate and orchestrate the asthmatic inflammatory response. In this article, we briefly review the role of allergen-specific CD4(+) T cells in the pathogenesis of human allergic airway inflammation in allergic individuals, discuss the use of allergen-major histocompatibility complex class II tetramers to characterize allergen-specific CD4(+) T cells, and highlight current gaps in knowledge and directions for future research pertaining to the role of allergen-specific CD4(+) T cells in human asthma. PMID:27027948

  11. Effectiveness of two synthetic fiber filters for removing white cells from AS-1 red cells.

    PubMed

    Pikul, F J; Farrar, R P; Boris, M B; Estok, L; Marlo, D; Wildgen, M; Chaplin, H

    1989-09-01

    Two commercially available synthetic fiber filters were studied for their effectiveness at removing white cells (WBCs) from AS-1-preserved red cells (RBCs) stored less than or equal to 14 days. In all, 65 filtrations were performed. An automated microprocessor-controlled hydraulic system designed for use with cellulose acetate fiber filters was employed to prepare filtered RBCs before release for transfusion. Studies were also carried out on polyester fiber filters, which are designed to be used in-line during transfusion. Residual WBCs were below the accurate counting range of Coulter counters and of conventional manual chamber counts. An isosmotic ammonium chloride RBC lysis method, plus a modified chamber counting technique, permitted a 270-fold increase over the number of WBCs counted by the conventional manual method. For the polyester fiber-filtered products, residual WBCs per unit were not affected by speed of filtration, prior length of storage, or mechanical tapping during filtration. The effectiveness of WBC removal (mean 99.7%), total residual WBCs (means, 4.8 and 5.5 x 10(6], and RBC recovery (mean, 93%) was the same for both filters. The majority of residual WBCs were lymphocytes. WBC removal and RBC recovery were strikingly superior to results reported with nonfiltration methods. PMID:2505411

  12. Sex Specification and Heterogeneity of Primordial Germ Cells in Mice

    PubMed Central

    Sakashita, Akihiko; Kawabata, Yukiko; Jincho, Yuko; Tajima, Shiun; Kumamoto, Soichiro; Kobayashi, Hisato; Matsui, Yasuhisa; Kono, Tomohiro

    2015-01-01

    In mice, primordial germ cells migrate into the genital ridges by embryonic day 13.5 (E13.5), where they are then subjected to a sex-specific fate with female and male primordial germ cells undergoing mitotic arrest and meiosis, respectively. However, the sex-specific basis of primordial germ cell differentiation is poorly understood. The aim of this study was to investigate the sex-specific features of mouse primordial germ cells. We performed RNA-sequencing (seq) of E13.5 female and male mouse primordial germ cells using next-generation sequencing. We identified 651 and 428 differentially expressed transcripts (>2-fold, P < 0.05) in female and male primordial germ cells, respectively. Of these, many transcription factors were identified. Gene ontology and network analysis revealed differing functions of the identified female- and male-specific genes that were associated with primordial germ cell acquisition of sex-specific properties required for differentiation into germ cells. Furthermore, DNA methylation and ChIP-seq analysis of histone modifications showed that hypomethylated gene promoter regions were bound with H3K4me3 and H3K27me3. Our global transcriptome data showed that in mice, primordial germ cells are decisively assigned to a sex-specific differentiation program by E13.5, which is necessary for the development of vital germ cells. PMID:26700643

  13. Mechanisms regulating dendritic cell specification and development

    PubMed Central

    Watowich, Stephanie S.; Liu, Yong-Jun

    2010-01-01

    Summary Understanding the diversification of dendritic cell (DC) lineages is one of the last frontiers in mapping the developmental hierarchy of the hematopoietic system. DCs are a vital link between the innate and adaptive immune responses, thus elucidating their developmental pathways is crucial for insight into the generation of natural immunity and for learning how to regulate DCs in clinical settings. DCs arise from hematopoietic stem cells through specialized progenitor subsets under the direction of FMS-like tyrosine kinase 3 ligand (Flt3L) and Flt3L receptor (Flt3) signaling. Recent studies have revealed important contributions from granulocyte-macrophage colony-stimulating factor (GM-CSF) and type I interferons (IFNs) in vivo. Furthermore, DC development is guided by lineage-restricted transcription factors such as IRF8, E2-2, and Batf3. A critical question centers on how cytokines and lineage-restricted transcription factors operate molecularly to direct DC diversification. Here we review recent findings that provide new insight into the DC developmental process. PMID:20969586

  14. Birthdating studies reshape models for pituitary gland cell specification.

    PubMed

    Davis, Shannon W; Mortensen, Amanda H; Camper, Sally A

    2011-04-15

    The intermediate and anterior lobes of the pituitary gland are derived from an invagination of oral ectoderm that forms Rathke's pouch. During gestation proliferating cells are enriched around the pouch lumen, and they appear to delaminate as they exit the cell cycle and differentiate. During late mouse gestation and the postnatal period, anterior lobe progenitors re-enter the cell cycle and expand the populations of specialized, hormone-producing cells. At birth, all cell types are present, and their localization appears stratified based on cell type. We conducted a birth dating study of Rathke's pouch derivatives to determine whether the location of specialized cells at birth is correlated with the timing of cell cycle exit. We find that all of the anterior lobe cell types initiate differentiation concurrently with a peak between e11.5 and e13.5. Differentiation of intermediate lobe melanotropes is delayed relative to anterior lobe cell types. We discovered that specialized cell types are not grouped together based on birth date and are dispersed throughout the anterior lobe. Thus, the apparent stratification of specialized cells at birth is not correlated with cell cycle exit. Thus, the currently popular model of cell specification, dependent upon timing of extrinsic, directional gradients of signaling molecules, needs revision. We propose that signals intrinsic to Rathke's pouch are necessary for cell specification between e11.5 and e13.5 and that cell-cell communication likely plays an important role in regulating this process. PMID:21262217

  15. Cell type-specific transcriptome profiling in mammalian brains.

    PubMed

    LoVerso, Peter R; Cui, Feng

    2016-01-01

    A mammalian brain contains numerous types of cells. Advances in neuroscience in the past decade allow us to identify and isolate neural cells of interest from mammalian brains. Recent developments in high-throughput technologies, such as microarrays and next-generation sequencing (NGS), provide detailed information on gene expression in pooled cells on a genomic scale. As a result, many novel genes have been found critical in cell type-specific transcriptional regulation. These differentially expressed genes can be used as molecular signatures, unique to a particular class of neural cells. Use of this gene expression-based approach can further differentiate neural cell types into subtypes, potentially linking some of them with neurological diseases. In this article, experimental techniques used to purify neural cells are described, followed by a review on recent microarray- or NGS-based transcriptomic studies of common neural cell types. The future prospects of cell type-specific research are also discussed. PMID:27100485

  16. Cell type-specific transcriptome profiling in mammalian brains

    PubMed Central

    LoVerso, Peter R.; Cui, Feng

    2016-01-01

    A mammalian brain contains numerous types of cells. Advances in neuroscience in the past decade allow us to identify and isolate neural cells of interest from mammalian brains. Recent developments in high-throughput technologies, such as microarrays and next-generation sequencing (NGS), provide detailed information on gene expression in pooled cells on a genomic scale. As a result, many novel genes have been found critical in cell type-specific transcriptional regulation. These differentially expressed genes can be used as molecular signatures, unique to a particular class of neural cells. Use of this gene expression-based approach can further differentiate neural cell types into subtypes, potentially linking some of them with neurological diseases. In this article, experimental techniques used to purify neural cells are described, followed by a review on recent microarray- or NGS-based transcriptomic studies of common neural cell types. The future prospects of cell type-specific research are also discussed. PMID:27100485

  17. The CellML Metadata Framework 2.0 Specification.

    PubMed

    Cooling, Michael T; Hunter, Peter

    2015-01-01

    The CellML Metadata Framework 2.0 is a modular framework that describes how semantic annotations should be made about mathematical models encoded in the CellML (www.cellml.org) format, and their elements. In addition to the Core specification, there are several satellite specifications, each designed to cater for model annotation in a different context. Basic Model Information, Citation, License and Biological Annotation specifications are presented. PMID:26528558

  18. Organ-Specific and Memory Treg Cells: Specificity, Development, Function, and Maintenance

    PubMed Central

    Gratz, Iris K.; Campbell, Daniel J.

    2014-01-01

    Foxp3+ regulatory T cells (Treg cells) are essential for establishing and maintaining self-tolerance, and also inhibit immune responses to innocuous environmental antigens. Imbalances and dysfunction in Treg cells lead to a variety of immune-mediated diseases, as deficits in Treg cell function contribute to the development autoimmune disease and pathological tissue damage, whereas overabundance of Treg cells can promote chronic infection and tumorigenesis. Recent studies have highlighted the fact that Treg cells themselves are a diverse collection of phenotypically and functionally specialized populations, with distinct developmental origins, antigen-specificities, tissue-tropisms, and homeostatic requirements. The signals directing the differentiation of these populations, their specificities and the mechanisms by which they combine to promote organ-specific and systemic tolerance, and how they embody the emerging property of regulatory memory are the focus of this review. PMID:25076948

  19. Marker-specific sorting of rare cells using dielectrophoresis

    PubMed Central

    Hu, Xiaoyuan; Bessette, Paul H.; Qian, Jiangrong; Meinhart, Carl D.; Daugherty, Patrick S.; Soh, Hyongsok T.

    2005-01-01

    Current techniques in high-speed cell sorting are limited by the inherent coupling among three competing parameters of performance: throughput, purity, and rare cell recovery. Microfluidics provides an alternate strategy to decouple these parameters through the use of arrayed devices that operate in parallel. To efficiently isolate rare cells from complex mixtures, an electrokinetic sorting methodology was developed that exploits dielectrophoresis (DEP) in microfluidic channels. In this approach, the dielectrophoretic amplitude response of rare target cells is modulated by labeling cells with particles that differ in polarization response. Cell mixtures were interrogated in the DEP-activated cell sorter in a continuous-flow manner, wherein the electric fields were engineered to achieve efficient separation between the dielectrophoretically labeled and unlabeled cells. To demonstrate the efficiency of marker-specific cell separation, DEP-activated cell sorting (DACS) was applied for affinity-based enrichment of rare bacteria expressing a specific surface marker from an excess of nontarget bacteria that do not express this marker. Rare target cells were enriched by >200-fold in a single round of sorting at a single-channel throughput of 10,000 cells per second. DACS offers the potential for automated, surface marker-specific cell sorting in a disposable format that is capable of simultaneously achieving high throughput, purity, and rare cell recovery. PMID:16236724

  20. Cell type-specific bipolar cell input to ganglion cells in the mouse retina.

    PubMed

    Neumann, S; Hüser, L; Ondreka, K; Auler, N; Haverkamp, S

    2016-03-01

    Many distinct ganglion cell types, which are the output elements of the retina, were found to encode for specific features of a visual scene such as contrast, color information or movement. The detailed composition of retinal circuits leading to this tuning of retinal ganglion cells, however, is apart from some prominent examples, largely unknown. Here we aimed to investigate if ganglion cell types in the mouse retina receive selective input from specific bipolar cell types or if they sample their synaptic input non-selectively from all bipolar cell types stratifying within their dendritic tree. To address this question we took an anatomical approach and immunolabeled retinae of two transgenic mouse lines (GFP-O and JAM-B) with markers for ribbon synapses and type 2 bipolar cells. We morphologically identified all green fluorescent protein (GFP)-expressing ganglion cell types, which co-stratified with type 2 bipolar cells and assessed the total number of bipolar input synapses and the proportion of synapses deriving from type 2 bipolar cells. Only JAM-B ganglion cells received synaptic input preferentially from bipolar cell types other than type 2 bipolar cells whereas the other analyzed ganglion cell types sampled their bipolar input most likely from all bipolar cell terminals within their dendritic arbor. PMID:26751712

  1. Integrated Droplet-Based Microextraction with ESI-MS for Removal of Matrix Interference in Single-Cell Analysis

    PubMed Central

    Zhang, Xiao-Chao; Wei, Zhen-Wei; Gong, Xiao-Yun; Si, Xing-Yu; Zhao, Yao-Yao; Yang, Cheng-Dui; Zhang, Si-Chun; Zhang, Xin-Rong

    2016-01-01

    Integrating droplet-based microfluidics with mass spectrometry is essential to high-throughput and multiple analysis of single cells. Nevertheless, matrix effects such as the interference of culture medium and intracellular components influence the sensitivity and the accuracy of results in single-cell analysis. To resolve this problem, we developed a method that integrated droplet-based microextraction with single-cell mass spectrometry. Specific extraction solvent was used to selectively obtain intracellular components of interest and remove interference of other components. Using this method, UDP-Glc-NAc, GSH, GSSG, AMP, ADP and ATP were successfully detected in single MCF-7 cells. We also applied the method to study the change of unicellular metabolites in the biological process of dysfunctional oxidative phosphorylation. The method could not only realize matrix-free, selective and sensitive detection of metabolites in single cells, but also have the capability for reliable and high-throughput single-cell analysis. PMID:27126222

  2. Mucorales-Specific T Cells in Patients with Hematologic Malignancies

    PubMed Central

    Forghieri, Fabio; Candoni, Anna; Cesaro, Simone; Quadrelli, Chiara; Maertens, Johan; Rossi, Giulio; Morselli, Monica; Codeluppi, Mauro; Mussini, Cristina; Colaci, Elisabetta; Messerotti, Andrea; Paolini, Ambra; Maccaferri, Monica; Fantuzzi, Valeria; Del Giovane, Cinzia; Stefani, Alessandro; Morandi, Uliano; Maffei, Rossana; Marasca, Roberto; Narni, Franco; Fanin, Renato; Comoli, Patrizia; Romani, Luigina; Beauvais, Anne; Viale, Pier Luigi; Latgè, Jean Paul; Luppi, Mario

    2016-01-01

    Background Invasive mucormycosis (IM) is an emerging life-threatening fungal infection. It is difficult to obtain a definite diagnosis and to initiate timely intervention. Mucorales-specific T cells occur during the course of IM and are involved in the clearance of the infection. We have evaluated the feasibility of detecting Mucorales-specific T cells in hematological patients at risk for IM, and have correlated the detection of such cells with the clinical conditions of the patients. Methods and Findings By using an enzyme linked immunospot assay, the presence of Mucorales-specific T cells in peripheral blood (PB) samples has been investigated at three time points during high-dose chemotherapy for hematologic malignancies. Mucorales-specific T cells producing interferon-γ, interleukin-10 and interleukin-4 were analysed in order to detect a correlation between the immune response and the clinical picture. Twenty-one (10.3%) of 204 patients, accounting for 32 (5.3%) of 598 PB samples, tested positive for Mucorales-specific T cells. Two groups could be identified. Group 1, including 15 patients without signs or symptoms of invasive fungal diseases (IFD), showed a predominance of Mucorales-specific T cells producing interferon-gamma. Group 2 included 6 patients with a clinical picture consistent with invasive fungal disease (IFD): 2 cases of proven IM and 4 cases of possible IFD. The proven patients had significantly higher number of Mucorales-specific T cells producing interleukin-10 and interleukin-4 and higher rates of positive samples by using derived diagnostic cut-offs when compared with the 15 patients without IFD. Conclusions Mucorales-specific T cells can be detected and monitored in patients with hematologic malignancies at risk for IM. Mucorales-specific T cells polarized to the production of T helper type 2 cytokines are associated with proven IM and may be evaluated as a surrogate diagnostic marker for IM. PMID:26871570

  3. 49 CFR 179.300 - General specifications applicable to multi-unit tank car tanks designed to be removed from car...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... tank car tanks designed to be removed from car structure for filling and emptying (Classes DOT-106A and...) SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300 General specifications applicable to multi-unit tank car tanks designed to be removed from car...

  4. 49 CFR 179.300 - General specifications applicable to multi-unit tank car tanks designed to be removed from car...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... tank car tanks designed to be removed from car structure for filling and emptying (Classes DOT-106A and...) SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300 General specifications applicable to multi-unit tank car tanks designed to be removed from car...

  5. 49 CFR 179.300 - General specifications applicable to multi-unit tank car tanks designed to be removed from car...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... tank car tanks designed to be removed from car structure for filling and emptying (Classes DOT-106A and...) SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300 General specifications applicable to multi-unit tank car tanks designed to be removed from car...

  6. 49 CFR 179.300 - General specifications applicable to multi-unit tank car tanks designed to be removed from car...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... tank car tanks designed to be removed from car structure for filling and emptying (Classes DOT-106A and...) SPECIFICATIONS FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300 General specifications applicable to multi-unit tank car tanks designed to be removed from car...

  7. Tissue Specific Heterogeneity in Effector Immune Cell Response

    PubMed Central

    Tufail, Saba; Badrealam, Khan Farheen; Sherwani, Asif; Gupta, Umesh D.; Owais, Mohammad

    2013-01-01

    Post pathogen invasion, migration of effector T-cell subsets to specific tissue locations is of prime importance for generation of robust immune response. Effector T cells are imprinted with distinct “homing codes” (adhesion molecules and chemokine receptors) during activation which regulate their targeted trafficking to specific tissues. Internal cues in the lymph node microenvironment along with external stimuli from food (vitamin A) and sunlight (vitamin D3) prime dendritic cells, imprinting them to play centre stage in the induction of tissue tropism in effector T cells. B cells as well, in a manner similar to effector T cells, exhibit tissue-tropic migration. In this review, we have focused on the factors regulating the generation and migration of effector T cells to various tissues along with giving an overview of tissue tropism in B cells. PMID:23986763

  8. Sertoli cells secrete both testis-specific and serum proteins.

    PubMed Central

    Wright, W W; Musto, N A; Mather, J P; Bardin, C W

    1981-01-01

    The secretions of the Sertoli cell were examined with two polyvalent antisera--one prepared against proteins in rat serum and the other against testis-specific proteins in rete testis fluid. These antisera detected 12 serum and 9 testis-specific proteins in rete testis fluid. To determine the origin of these proteins, primary cultures enriched in Sertoli cells were incubated with [35S]methionine, and the radiolabeled proteins in the medium were immunoprecipitated. Gel electrophoresis of the two immunoprecipitates resolved eight serum and nine testis-specific proteins. These two sets of proteins were specifically bound to their respective antiserum and were immunologically distinct. Medium from Sertoli cell cultures contained 10 times more of the testis-specific proteins than did cultures enriched for testicular myoid or interstitial cells. The concentration of the serum proteins in Sertoli cell medium was 5 and 10 times greater, respectively, than in myoid or interstitial cell preparations. The proteins from Sertoli cells were next characterized on two-dimensional gels. Seven of the proteins recognized by antiserum against serum proteins had identical molecular weights and isoelectric points as serum proteins. Three of these proteins were ceruloplasmin, transferrin, and glycoprotein 2. In addition to the proteins immunoprecipitated by the two antisera, more than 60 other proteins were detected on two-dimensional gels of the total secretory proteins. We conclude that the Sertoli cell secretes many proteins, some of which are specific to the testis and others of which are similar to serum proteins. Images PMID:6950398

  9. An association between antibodies specific for endothelial cells and renal transplant failure.

    PubMed

    Perrey, C; Brenchley, P E; Johnson, R W; Martin, S

    1998-06-01

    Human leucocyte antigen (HLA)-specific antibodies, present at the time of transplant, cause renal transplant rejection but cases of rejection of HLA-identical renal transplants indicate that antibodies to non-HLA antigens may also be detrimental. There is increasing evidence that antibodies to antigens present on endothelial cells and monocytes, and on endothelial cells alone, are associated with transplant rejection. We investigated 105 patients with failed renal transplants for the presence of endothelial cell reactive antibodies and compared them with 94 successful transplant patients to determine the role of non-HLA antibodies in transplant failure. Patient sera were tested by enzyme-linked immunoabsorbent assay (ELISA) using as a target fixed cells either from the endothelial/epithelial cell line EAHy.926 or primary cultures of human umbilical vein endothelial cells. Antibody binding was detected using an alkaline phosphatase-conjugated anti-human immunoglobulin G (IgG) antibody. Fourteen of the 105 failed transplant patients had endothelial cell-reactive antibodies as compared with only three of the 94 patients with successful transplants (Fisher's exact test, p = 0.02). Antibody-positive sera were absorbed with the epithelial cell line A549 to remove antibodies directed against the epithelial component of EAHy.926 and with a pool of lymphoblastoid cell line cells to remove HLA-specific antibodies. Absorption did not reduce antibody activity showing the antibodies to be directed against endothelial cell determinants. Antibody-positive sera were also tested by flow cytometry against the monocyte cell line THP-1 and 13 of the 14 patients were negative. In conclusion, we have demonstrated the presence of IgG antibodies directed against endothelial cell determinants in renal transplant recipients in association with renal transplant failure. PMID:9777698

  10. The selection and function of cell type-specific enhancers.

    PubMed

    Heinz, Sven; Romanoski, Casey E; Benner, Christopher; Glass, Christopher K

    2015-03-01

    The human body contains several hundred cell types, all of which share the same genome. In metazoans, much of the regulatory code that drives cell type-specific gene expression is located in distal elements called enhancers. Although mammalian genomes contain millions of potential enhancers, only a small subset of them is active in a given cell type. Cell type-specific enhancer selection involves the binding of lineage-determining transcription factors that prime enhancers. Signal-dependent transcription factors bind to primed enhancers, which enables these broadly expressed factors to regulate gene expression in a cell type-specific manner. The expression of genes that specify cell type identity and function is associated with densely spaced clusters of active enhancers known as super-enhancers. The functions of enhancers and super-enhancers are influenced by, and affect, higher-order genomic organization. PMID:25650801

  11. Angiocrine functions of organ-specific endothelial cells

    PubMed Central

    Rafii, Shahin; Butler, Jason M; Ding, Bi-Sen

    2016-01-01

    Preface Endothelial cells lining blood vessel capillaries are not just passive conduits for delivering blood. Tissue-specific endothelium establish specialized vascular niches that deploy specific sets of growth factors, known as angiocrine factors, which actively participate in inducing, specifying, patterning, and guiding organ regeneration and maintaining homeostasis and metabolism. Angiocrine factors upregulated in response to injury orchestrates self-renewal and differentiation of tissue-specific repopulating resident stem and progenitor cells into functional organs. Uncovering the precise mechanisms whereby physiological-levels of angiocrine factors are spatially and temporally produced, and distributed by organotypic endothelium to repopulating cells, will lay the foundation for driving organ repair without scarring. PMID:26791722

  12. Isolating specific embryonic cells of the sea urchin by FACS.

    PubMed

    Juliano, Celina; Swartz, S Zachary; Wessel, Gary

    2014-01-01

    Isolating cells based on specific gene expression enables a focused biochemical and molecular analysis. While cultured cells and hematopoietic cells, for example, are routinely isolated by fluorescence activated cell sorting (FACS), early embryonic cells are a relatively untapped source for FACS applications often because the embryos of many animals are quite limiting. Furthermore, many applications require genetic model organisms in which cells can be labeled by fluorescent transgenes, or antibodies against cell surface antigens. Here we define conditions in the sea urchin embryo for isolation of embryonic cells based on expression of specific proteins. We use the sea urchin embryo for which a nearly unlimited supply of embryonic cells is available and demonstrate the conditions for separation of the embryo into single cells, fixation of the cells for antibody penetration into the cells, and conditions for FACS of a rare cell type in the embryo. This protocol may be adapted for analysis of mRNA, chromatin, protein, or carbohydrates and depends only on the probe availability for the cell of interest. We anticipate that this protocol will be broadly applicable to embryos of other species. PMID:24567215

  13. Organ-specific features of natural killer cells

    PubMed Central

    Shi, Fu-Dong; Ljunggren, Hans-Gustaf; La Cava, Antonio; Van Kaer, Luc

    2013-01-01

    Natural killer (NK) cells can be swiftly mobilized by danger signals and are among the earliest arrivals at target organs of disease. However, the role of NK cells in mounting inflammatory responses is often complex and sometimes paradoxical. Here, we examine the divergent phenotypic and functional features of NK cells, as deduced largely from experimental mouse models of pathophysiological responses in the liver, mucosal tissues, uterus, pancreas, joints and brain. Moreover, we discuss how organ-specific factors, the local microenvironment and unique cellular interactions may influence the organ-specific properties of NK cells. PMID:21941294

  14. High specific energy, high capacity nickel-hydrogen cell design

    NASA Technical Reports Server (NTRS)

    Wheeler, James R.

    1993-01-01

    A 3.5 inch rabbit-ear-terminal nickel-hydrogen cell has been designed and tested to deliver high capacity at a C/1.5 discharge rate. Its specific energy yield of 60.6 wh/kg is believed to be the highest yet achieved in a slurry-process nickel-hydrogen cell, and its 10 C capacity of 113.9 AH the highest capacity yet made at a discharge rate this high in the 3.5 inch diameter size. The cell also demonstrated a pulse capability of 180 amps for 20 seconds. Specific cell parameters, performance, and future test plans are described.

  15. Heparin induces the expression of specific matrix proteins by human intestinal smooth muscle cells

    SciTech Connect

    Cochran, D.L.; Perr, H.; Graham, M.F.; Diegelmann, R.F.

    1986-03-01

    Human intestinal smooth muscle (HISM) cells have recently been identified as the major cell type responsible for stricture formation in Crohn's disease. Heparin, a sulfated glycosaminoglycan, has been shown to be a key modulator of vascular smooth muscle cell (VSMC) growth both in vivo and in vitro and to affect the phenotypic expression of proteins made by VSMC. Heparin has also been shown to effect the growth of HISM cells and in this report the authors demonstrate that heparin also has very specific effects on proteins released by HISM cells in vitro. Examination of the proteins in the culture medium of heparin-treated HISM cells observed at 3 time points following sparse plating and proliferation revealed an increase in /sup 35/S-methionine-labeled 200, 37, and 35 kd proteins. A transient effect on a 48 kd protein was observed in substrate-attached material left on the culture dish after the cells were removed with EGTA. No effects on intracellular labeled proteins could be demonstrated. The protein phenotype of HISM cells exposed to heparin appears very similar to that observed in VSMC. The release of specific proteins following exposure to heparin does not appear to be species specific. This response to heparin may reflect a significant influence of this glycosaminoglycan on the phenotypic expression of these cells.

  16. Cell-specific translational profiling in acute kidney injury

    PubMed Central

    Liu, Jing; Krautzberger, A. Michaela; Sui, Shannan H.; Hofmann, Oliver M.; Chen, Ying; Baetscher, Manfred; Grgic, Ivica; Kumar, Sanjeev; Humphreys, Benjamin; Hide, Winston A.; McMahon, Andrew P.

    2014-01-01

    Acute kidney injury (AKI) promotes an abrupt loss of kidney function that results in substantial morbidity and mortality. Considerable effort has gone toward identification of diagnostic biomarkers and analysis of AKI-associated molecular events; however, most studies have adopted organ-wide approaches and have not elucidated the interplay among different cell types involved in AKI pathophysiology. To better characterize AKI-associated molecular and cellular events, we developed a mouse line that enables the identification of translational profiles in specific cell types. This strategy relies on CRE recombinase–dependent activation of an EGFP-tagged L10a ribosomal protein subunit, which allows translating ribosome affinity purification (TRAP) of mRNA populations in CRE-expressing cells. Combining this mouse line with cell type–specific CRE-driver lines, we identified distinct cellular responses in an ischemia reperfusion injury (IRI) model of AKI. Twenty-four hours following IRI, distinct translational signatures were identified in the nephron, kidney interstitial cell populations, vascular endothelium, and macrophages/monocytes. Furthermore, TRAP captured known IRI-associated markers, validating this approach. Biological function annotation, canonical pathway analysis, and in situ analysis of identified response genes provided insight into cell-specific injury signatures. Our study provides a deep, cell-based view of early injury-associated molecular events in AKI and documents a versatile, genetic tool to monitor cell-specific and temporal-specific biological processes in disease modeling. PMID:24569379

  17. A comparison of simultaneous organic carbon and nitrogen removal in microbial fuel cells and microbial electrolysis cells.

    PubMed

    Hussain, Abid; Manuel, Michelle; Tartakovsky, Boris

    2016-05-15

    This study demonstrates simultaneous carbon and nitrogen removal in laboratory-scale continuous flow microbial fuel cell (MFC) and microbial electrolysis cell (MEC) and provides side-by side comparison of these bioelectrochemical systems. The maximum organic carbon removal rates in MFC and MEC tests were similar at 5.1 g L(-1) d(-1) and 4.16 g L(-1) d(-1), respectively, with a near 100% carbon removal efficiency at an organic load of 3.3 g L(-1) d(-1). An ammonium removal efficiency of 30-55% with near-zero nitrite and nitrate concentrations was observed in the MFC operated at an optimal external resistance, while open-circuit MFC operation resulted in a reduced carbon and ammonium removal of 53% and 21%, respectively. In the MEC ammonium removal was limited to 7-12% under anaerobic conditions, while micro-aerobic conditions increased the removal efficiency to 31%. Also, at zero applied voltage both carbon and ammonium removal efficiencies were reduced to 42% and 4%, respectively. Based on the observed performance under different operating conditions, it was concluded that simultaneous carbon and nitrogen removal was facilitated by concurrent anaerobic and aerobic biotransformation pathways at the anode and cathode, which balanced bioelectrochemical nitrification and denitrification reactions. PMID:26950500

  18. Parametric Study to Characterize Low Activity Waste Tank Heat Removal Alternatives for Phase 1 Specification Development

    SciTech Connect

    GRENARD, C.E.

    2000-09-11

    Alternative for removing heat from Phase 1, low-activity waste feed double-shell tanks using the ventilation systems have been analyzed for Phase 1 waste feed delivery. The analysis was a parametric study using a model that predicted the waste temperatures for a range of primary and annulus ventilation system flow rates. The analysis was performed to determine the ventilation flow required to prevent the waste temperature from exceeding the Limiting Conditions for Operation limits during normal operation and the Safety Limits during off-normal events.

  19. Murine somatic cell nuclear transfer using reprogrammed donor cells expressing male germ cell-specific genes.

    PubMed

    Kang, Hoin; Park, Jong Im; Roh, Sangho

    2016-01-01

    In vivo-matured mouse oocytes were enucleated, and a single murine embryonic fibroblast (control or reprogrammed by introducing extracts from murine testis tissue, which showed expression of male germ cell-specific genes) was injected into the cytoplasm of the oocytes. The rate of blastocyst development and expression levels of Oct-4, Eomes and Cdx-2 were not significantly different in both experimental groups. However, the expression levels of Nanog, Sox9 and Glut-1 were significantly increased when reprogrammed cells were used as donor nuclei. Increased expression of Nanog can be supportive of complete reprogramming of somatic cell nuclear transfer murine embryos. The present study suggested that donor cells expressing male germ cell-specific genes can be reconstructed and can develop into embryos with normal high expression of developmentally essential genes. PMID:26369430

  20. Galectin-1 Regulates Tissue Exit of Specific Dendritic Cell Populations*

    PubMed Central

    Thiemann, Sandra; Man, Jeanette H.; Chang, Margaret H.; Lee, Benhur; Baum, Linda G.

    2015-01-01

    During inflammation, dendritic cells emigrate from inflamed tissue across the lymphatic endothelium into the lymphatic vasculature and travel to regional lymph nodes to initiate immune responses. However, the processes that regulate dendritic cell tissue egress and migration across the lymphatic endothelium are not well defined. The mammalian lectin galectin-1 is highly expressed by vascular endothelial cells in inflamed tissue and has been shown to regulate immune cell tissue entry into inflamed tissue. Here, we show that galectin-1 is also highly expressed by human lymphatic endothelial cells, and deposition of galectin-1 in extracellular matrix selectively regulates migration of specific human dendritic cell subsets. The presence of galectin-1 inhibits migration of immunogenic dendritic cells through the extracellular matrix and across lymphatic endothelial cells, but it has no effect on migration of tolerogenic dendritic cells. The major galectin-1 counter-receptor on both dendritic cell populations is the cell surface mucin CD43; differential core 2 O-glycosylation of CD43 between immunogenic dendritic cells and tolerogenic dendritic cells appears to contribute to the differential effect of galectin-1 on migration. Binding of galectin-1 to immunogenic dendritic cells reduces phosphorylation and activity of the protein-tyrosine kinase Pyk2, an effect that may also contribute to reduced migration of this subset. In a murine lymphedema model, galectin-1−/− animals had increased numbers of migratory dendritic cells in draining lymph nodes, specifically dendritic cells with an immunogenic phenotype. These findings define a novel role for galectin-1 in inhibiting tissue emigration of immunogenic, but not tolerogenic, dendritic cells, providing an additional mechanism by which galectin-1 can dampen immune responses. PMID:26216879

  1. Gas block mechanism for water removal in fuel cells

    DOEpatents

    Issacci, Farrokh; Rehg, Timothy J.

    2004-02-03

    The present invention is directed to apparatus and method for cathode-side disposal of water in an electrochemical fuel cell. There is a cathode plate. Within a surface of the plate is a flow field comprised of interdigitated channels. During operation of the fuel cell, cathode gas flows by convection through a gas diffusion layer above the flow field. Positioned at points adjacent to the flow field are one or more porous gas block mediums that have pores sized such that water is sipped off to the outside of the flow field by capillary flow and cathode gas is blocked from flowing through the medium. On the other surface of the plate is a channel in fluid communication with each porous gas block mediums. The method for water disposal in a fuel cell comprises installing the cathode plate assemblies at the cathode sides of the stack of fuel cells and manifolding the single water channel of each of the cathode plate assemblies to the coolant flow that feeds coolant plates in the stack.

  2. Engineering Human Peripheral Blood Stem Cell Grafts That Are Depleted of Naïve T Cells and Retain Functional Pathogen-Specific Memory T cells

    PubMed Central

    Bleakley, Marie; Heimfeld, Shelly; Jones, Lori A.; Turtle, Cameron; Riddell, Stanley R.; Shlomchik, Warren

    2014-01-01

    Graft-versus-host disease (GVHD) is a frequent major complication of allogeneic hematopoietic cell transplantation (HCT). The development of approaches that selectively deplete T cells that cause GVHD from allogeneic stem cell grafts and preserve T cells specific for pathogens may improve HCT outcomes. It has been hypothesized that the majority of T cells that can cause GVHD reside within the naïve T cell (TN) subset, and previous studies performed in mouse models and with human cells in vitro support this hypothesis. As a prelude to translating these findings to the clinic, we developed and evaluated a novel, two-step, clinically compliant procedure for manipulating peripheral blood stem cells (PBSC) to remove TN, preserve CD34+ hematopoietic stem cells, and provide for a fixed dose of memory T cells (TM) that includes T cells with specificity for common opportunistic pathogens encountered after HCT. Our studies demonstrate effective and reproducible performance of the immunomagnetic cell selection procedure for depleting TN. Moreover, after cell processing the CD45RA-depleted PBSC products are enriched for CD4+ and CD8+ TM with a central memory phenotype and contain TM cells that are capable of proliferating and producing effector cytokines in response to opportunistic pathogens. PMID:24525279

  3. Cell-Specific Multifunctional Processing of Heterogeneous Cell Systems in a Single Laser Pulse Treatment

    PubMed Central

    Lukianova-Hleb, Ekaterina Y.; Mutonga, Martin B. G.; Lapotko, Dmitri O.

    2012-01-01

    Current methods of cell processing for gene and cell therapies use several separate procedures for gene transfer and cell separation or elimination, because no current technology can offer simultaneous multi-functional processing of specific cell sub-sets in highly heterogeneous cell systems. Using the cell-specific generation of plasmonic nanobubbles of different sizes around cell-targeted gold nanoshells and nanospheres, we achieved simultaneous multifunctional cell-specific processing in a rapid single 70 ps laser pulse bulk treatment of heterogeneous cell suspension. This method supported the detection of cells, delivery of external molecular cargo to one type of cells and the concomitant destruction of another type of cells without damaging other cells in suspension, and real-time guidance of the two above cellular effects. PMID:23167546

  4. Multilayered specification of the T-cell lineage fate

    PubMed Central

    Rothenberg, Ellen V.; Zhang, Jingli; Li, Long

    2010-01-01

    Summary T-cell development from stem cells has provided a highly accessible and detailed view of the regulatory processes that can go into the choice of a cell fate in a postembryonic, stem cell-based system. But, it has been a view from the outside. The problems in understanding the regulatory basis for this lineage choice begin with the fact that too many transcription factors are needed to provide crucial input: without any one of them, T-cell development fails. Furthermore, almost all the factors known to provide crucial functions during the climax of T-lineage commitment itself are also vital for earlier functions that establish the pool of multilineage precursors that would normally feed into the T-cell specification process. When the regulatory genes that encode them are mutated, the confounding effects on earlier stages make it difficult to dissect T-cell specification genetically. Yet both the positive and the negative regulatory events involved in the choice of a T-cell fate are actually a mosaic of distinct functions. New evidence has emerged recently that finally provides a way to separate the major components that fit together to drive this process. Here, we review insights into T-cell specification and commitment that emerge from a combination of molecular, cellular, and systems biology approaches. The results reveal the regulatory structure underlying this lineage decision. PMID:20969591

  5. Electrical detection of specific versus non-specific binding events in breast cancer cells

    NASA Astrophysics Data System (ADS)

    King, Benjamin C.; Clark, Michael; Burkhead, Thomas; Sethu, Palaniappan; Rai, Shesh; Kloecker, Goetz; Panchapakesan, Balaji

    2012-10-01

    Detection of circulating tumor cells (CTCs) from patient blood samples offers a desirable alternative to invasive tissue biopsies for screening of malignant carcinomas. A rigorous CTC detection method must identify CTCs from millions of other formed elements in blood and distinguish them from healthy tissue cells also present in the blood. CTCs are known to overexpress surface receptors, many of which aid them in invading other tissue, and these provide an avenue for their detection. We have developed carbon nanotube (CNT) thin film devices to specifically detect these receptors in intact cells. The CNT sidewalls are functionalized with antibodies specific to Epithelial Cell Adhesion Molecule (EpCAM), a marker overexpressed by breast and other carcinomas. Specific binding of EpCAM to anti-EpCAM antibodies causes a change in the local charge environment of the CNT surface which produces a characteristic electrical signal. Two cell lines were tested in the device: MCF7, a mammary adenocarcinoma line which overexpresses EpCAM, and MCF10A, a non-tumorigenic mammary epithelial line which does not. Introduction of MCF7s caused significant changes in the electrical conductance of the devices due to specific binding and associated charge environment change near the CNT sidewalls. Introduction of MCF10A displays a different profile due to purely nonspecific interactions. The profile of specific vs. nonspecific interaction signatures using carbon based devices will guide development of this diagnostic tool towards clinical sample volumes with wide variety of markers.

  6. Circulating tumor cell detection using carbon nanotube devices: specific versus non-specific interactions

    PubMed Central

    King, Benjamin C.; Burkhead, Thomas; Panchapakesan, Balaji

    2013-01-01

    Detection of circulating tumor cells (CTCs) from patient blood samples offers a desirable alternative to invasive tissue biopsies for screening of malignant carcinomas. A rigorous CTC detection method must identify CTCs from millions of other formed elements in blood and distinguish them from healthy tissue cells also present in the blood. CTCs are known to overexpress certain surface receptors, many of which aid them in invading other tissue, and these provide an avenue for their detection. We have developed carbon nanotube (CNT) thin film devices to specifically detect these receptors in intact cells. The CNT sidewalls are functionalized with antibodies specific to Epithelial Cell Adhesion Molecule (EpCAM), a marker overexpressed by breast and other carcinomas. Specific binding of EpCAM to anti-EpCAM causes a change in the local charge environment of the CNT surface which produces a characteristic electrical signal. Two cell lines are tested in the device: MCF7, a mammary adenocarcinoma line which overexpresses EpCAM, and MCF10A, a non-tumorigenic mammary epithelial line which does not. Introduction of MCF7s causes significant changes in the electrical conductance of the devices due to specific binding and associated charge environment change near the CNT sidewalls. Introduction of MCF10A displays a different profile due to purely nonspecific interactions. The profile of specific vs. nonspecific interaction signatures using carbon based devices will guide development of this diagnostic tool towards clinical sample volumes.

  7. Modeling BOD removal in constructed wetlands with mixing cell method

    SciTech Connect

    Chen, S.; Wang, G.T.; Xue, S.K.

    1999-01-01

    A new concept, transport detention time, is proposed in this paper to describe solute-transport processes. Using this concept, a new mathematical model was developed to describe biochemical oxygen demand removal in constructed wetlands. By treating a constructed wetland as a series of continuous stir tank reactors, an nth-order ordinary differential equation was derived based on the principle of mass balance and convective-dispersive equation and by introducing transfer function and Laplace transform. The number of continuous stir tank reactors of a particular wetland was determined by the parameters, such as dispersion coefficient and flow velocity, occurring in the wetland. Two examples were presented to illustrate the applications of the model. Moment method and a combination of moment and optimization methods were used to estimate the model parameters from tracer experiment data. A comparison between the model presented in this paper and the currently used plug-flow-constructed wetland model indicated that the former was more accurate. Additionally, this model can be applied to transient conditions, is theoretically sound, and represents a theoretical advance in constructed wetland research.

  8. pH-dependent ammonia removal pathways in microbial fuel cell system.

    PubMed

    Kim, Taeyoung; An, Junyeong; Lee, Hyeryeong; Jang, Jae Kyung; Chang, In Seop

    2016-09-01

    In this work, ammonia removal paths in microbial fuel cells (MFCs) under different initial pH conditions (pH 7.0, 8.0, and 8.6) were investigated. At a neutral pH condition (pH 7.0), MFC used an electrical energy of 27.4% and removed 23.3% of total ammonia by electrochemical pathway for 192h. At the identical pH condition, 36.1% of the total ammonia was also removed by the biological path suspected to be biological ammonia oxidation process (e.g., Anammox). With the initial pH increased, the electrochemical removal efficiency decreased to less than 5.0%, while the biological removal efficiency highly increased to 61.8%. In this study, a neutral pH should be maintained in the anode to utilize MFCs for ammonia recovery via electrochemical pathways from wastewater stream. PMID:27090407

  9. Angiocrine functions of organ-specific endothelial cells.

    PubMed

    Rafii, Shahin; Butler, Jason M; Ding, Bi-Sen

    2016-01-21

    Endothelial cells that line capillaries are not just passive conduits for delivering blood. Tissue-specific endothelium establishes specialized vascular niches that deploy sets of growth factors, known as angiocrine factors. These cues participate actively in the induction, specification, patterning and guidance of organ regeneration, as well as in the maintainance of homeostasis and metabolism. When upregulated following injury, they orchestrate self-renewal and differentiation of tissue-specific resident stem and progenitor cells into functional organs. Uncovering the mechanisms by which organotypic endothelium distributes physiological levels of angiocrine factors both spatially and temporally will lay the foundation for clinical trials that promote organ repair without scarring. PMID:26791722

  10. Removing the mustard oil bomb from seeds: transgenic ablation of myrosin cells in oilseed rape (Brassica napus) produces MINELESS seeds

    PubMed Central

    Borgen, Birgit Hafeld; Thangstad, Ole Petter; Ahuja, Ishita; Rossiter, John Trevor; Bones, Atle Magnar

    2010-01-01

    Many plant phytochemicals constitute binary enzyme–glucoside systems and function in plant defence. In brassicas, the enzyme myrosinase is confined to specific myrosin cells that separate the enzyme from its substrate; the glucosinolates. The myrosinase-catalysed release of toxic and bioactive compounds such as isothiocyanates, upon activation or tissue damage, has been termed ‘the mustard oil bomb’ and characterized as a ‘toxic mine’ in plant defence. The removal of myrosin cells and the enzyme that triggers the release of phytochemicals have been investigated by genetically modifying Brassica napus plants to remove myrosinase-storing idioblasts. A construct with the seed myrosin cell-specific Myr1.Bn1 promoter was used to express a ribonuclease, barnase. Transgenic plants ectopically expressing barnase were embryo lethal. Co-expressing barnase under the control of the Myr1.Bn1 promoter with the barnase inhibitor, barstar, under the control of the cauliflower mosaic virus 35S promoter enabled a selective and controlled death of myrosin cells without affecting plant viability. Ablation of myrosin cells was confirmed with light and electron microscopy, with immunohistological analysis and immunogold-electron microscopy analysis showing empty holes where myrosin cells normally are localized. Further evidence for a successful myrosin cell ablation comes from immunoblots showing absence of myrosinase and negligible myrosinase activity, and autolysis experiments showing negligible production of glucosinolate hydrolysis products. The plants where the myrosin defence cells have been ablated and named ‘MINELESS plants’. The epithiospecifier protein profile and glucosinolate levels were changed in MINELESS plants, pointing to localization of myrosinases and a 35 kDa epithiospecifier protein in myrosin cells and a reduced turnover of glucosinolates in MINELESS plants. PMID:20219777

  11. Overexpression of apoptotic cell removal receptor MERTK in alveolar macrophages of cigarette smokers.

    PubMed

    Kazeros, Angeliki; Harvey, Ben-Gary; Carolan, Brendan J; Vanni, Holly; Krause, Anja; Crystal, Ronald G

    2008-12-01

    Mononuclear phagocytes play an important role in the removal of apoptotic cells by expressing cell surface receptors that recognize and remove apoptotic cells. Based on the knowledge that cigarette smoking is associated with increased lung cell turnover, we hypothesized that alveolar macrophages (AMs) of normal cigarette smokers may exhibit enhanced expression of apoptotic cell removal receptor genes. AMs obtained by bronchoalveolar lavage of normal nonsmokers (n = 11) and phenotypic normal smokers (n = 13; 36 +/- 6 pack-years) were screened for mRNA expression of all known apoptotic cell removal receptors using Affymetrix HG-U133 Plus 2.0 microarray chips with TaqMan RT-PCR confirmation. Of the 14 known apoptotic receptors expressed, only MER tyrosine kinase (MERTK), a transmembrane tyrosine kinase receptor, was significantly up-regulated in smokers. MERTK expression was then assessed in AMs of smokers versus nonsmokers by TaqMan RT-PCR, immunocytochemistry, Western analysis, and flow analysis. Smoker AMs had up-regulation of MERTK mRNA levels (smoker vs. nonsmoker: 3.6-fold by microarray, P < 0.003; 9.5-fold by TaqMan RT-PCR, P < 0.02). Immunocytochemistry demonstrated a qualitative increase in MERTK protein expression on AMs of smokers. Increased protein expression of MERTK on AMs of smokers was confirmed by Western and flow analyses (P < 0.007 and P < 0.0002, respectively). MERTK, a cell surface receptor that recognizes apoptotic cells, is expressed on human AMs, and its expression is up-regulated in AMs of cigarette smokers. This up-regulation of MERTK may reflect an increased demand for removal of apoptotic cells in smokers, an observation with implications for the development of chronic obstructive pulmonary disease, a disorder associated with dysregulated apoptosis of lung parenchymal cells. PMID:18587056

  12. Control of NKT cell differentiation by tissue-specific microenvironments.

    PubMed

    Yang, Yang; Ueno, Aito; Bao, Min; Wang, Zhongying; Im, Jin Seon; Porcelli, Steven; Yoon, Ji-Won

    2003-12-01

    CD1d-restricted Valpha14 NKT cells play an important role in both Th1- and Th2-type immune responses. To determine whether NKT cells develop two functionally distinct subsets that provoke different types of responses, we examined the phenotypes and cellular functions of NK1.1(+) and DX5(+) T cells. We found that both NK1.1(+) and DX5(+) T cells are CD1d-restricted Valpha14 T cells with identical Ag specificities, phenotypes, tissue locations, and functions. Similar to the NK1.1 marker, the DX5 marker (CD49b) is expressed on mature NKT cells in both NK1.1 allele-positive and allele-negative strains. However, when NK1.1(+) and DX5(+) NKT cells isolated from different tissues were compared, we found that thymic and splenic NKT cells differed not only in their cytokine profiles, but also in their phenotype and requirements for costimulatory signals. Thymic NKT cells displayed the phenotype of activated T cells and could be fully activated by TCR ligation. In contrast, splenic NKT cells displayed the phenotype of memory T cells and required a costimulatory signal for activation. Furthermore, the function and phenotype of thymic and splenic NKT cells were modulated by APCs from various tissues that expressed different levels of costimulatory molecules. Modulation of NKT cell function and differentiation may be mediated by synergic effects of costimulatory molecules on the surface of APCs. The results of the present study suggest that the costimulatory signals of tissue-specific APCs are key factors for NKT cell differentiation, and these signals cannot be replaced by anti-CD28 or anti-CD40 ligand Abs. PMID:14634102

  13. Performance and recent improvement in microbial fuel cells for simultaneous carbon and nitrogen removal: A review.

    PubMed

    Sun, Haishu; Xu, Shengjun; Zhuang, Guoqiang; Zhuang, Xuliang

    2016-01-01

    Microbial fuel cells (MFCs) have become a promising technology for wastewater treatment accompanying electricity generation. Carbon and nitrogen removal can be achieved by utilizing the electron transfer between the anode and cathode in an MFC. However, large-scale power production and high removal efficiency must be achieved at a low cost to make MFCs practical and economically competitive in the future. This article reviews the principles, feasibility and bottlenecks of MFCs for simultaneous carbon and nitrogen removal, the recent advances and prospective strategies for performance improvement, as well as the involved microbes and electron transfer mechanisms. PMID:26899662

  14. Distinct interactions select and maintain a specific cell fate

    PubMed Central

    Dončić, Andreas; Falleur-Fettig, Melody; Skotheim, Jan M.

    2011-01-01

    The ability to specify and maintain discrete cell fates is essential for development. However, the dynamics underlying selection and stability of distinct cell types remains poorly understood. Here, we provide a quantitative single-cell analysis of commitment dynamics during the mating-mitosis switch in budding yeast. Commitment to division corresponds precisely to activating the G1 cyclin positive feedback loop in competition with the cyclin inhibitor Far1. Cyclin-dependent phosphorylation and inhibition of the mating pathway scaffold Ste5 is required to ensure exclusive expression of the mitotic transcriptional program after cell cycle commitment. Failure to commit exclusively results in coexpression of both cell cycle and pheromone-induced genes, and a morphologically-mixed inviable cell fate. Thus, specification and maintenance of a cellular state are performed by distinct interactions, which is likely a consequence of disparate reaction rates and may be a general feature of the interlinked regulatory networks responsible for selecting cell fates. PMID:21855793

  15. Coupling of anaerobic digester and microbial fuel cell for COD removal and ammonia recovery.

    PubMed

    Kim, Taeyoung; An, Junyeong; Jang, Jae Kyung; Chang, In Seop

    2015-11-01

    Microbial fuel cells (MFCs) were investigated for use in removing total ammonia nitrogen (TAN) and residual COD from effluent digested in an anaerobic digester (AD) fed with actual swine wastewater for 32 days in batch mode. Cumulative COD removal in the AD was as high as 59,647±2096 mg/L (80.5% removed), whereas TAN removal in the AD was negligible at 296±116 mg-N/L (5.8% removed), causing a decrease in the COD/TAN ratio from 14.5 to 3.0. In a subsequent MFC system, 77.5% of TAN was removed at 36 days, leading to an increase in COD/TAN ratio from 4.6 to 8.1. As a result, the COD in the anode was further reduced from 19,319±417 mg/L to 7519±554 mg/L (61.1% removed). From these results, removing the TAN in MFCs was found to increase the COD/TAN ratio, with the COD being further degraded. PMID:26142819

  16. Cell-specific DNA methylation patterns of retina-specific genes.

    PubMed

    Merbs, Shannath L; Khan, Miriam A; Hackler, Laszlo; Oliver, Verity F; Wan, Jun; Qian, Jiang; Zack, Donald J

    2012-01-01

    Many studies have demonstrated that epigenetic mechanisms are important in the regulation of gene expression during embryogenesis, gametogenesis, and other forms of tissue-specific gene regulation. We sought to explore the possible role of epigenetics, specifically DNA methylation, in the establishment and maintenance of cell type-restricted gene expression in the retina. To assess the relationship between DNA methylation status and expression level of retinal genes, bisulfite sequence analysis of the 1000 bp region around the transcription start sites (TSS) of representative rod and cone photoreceptor-specific genes and gene expression analysis were performed in the WERI and Y79 human retinoblastoma cell lines. Next, the homologous genes in mouse were bisulfite sequenced in the retina and in non-expressing tissues. Finally, bisulfite sequencing was performed on isolated photoreceptor and non-photoreceptor retinal cells isolated by laser capture microdissection. Differential methylation of rhodopsin (RHO), retinal binding protein 3 (RBP3, IRBP) cone opsin, short-wave-sensitive (OPN1SW), cone opsin, middle-wave-sensitive (OPN1MW), and cone opsin, long-wave-sensitive (OPN1LW) was found in the retinoblastoma cell lines that inversely correlated with gene expression levels. Similarly, we found tissue-specific hypomethylation of the promoter region of Rho and Rbp3 in mouse retina as compared to non-expressing tissues, and also observed hypomethylation of retinal-expressed microRNAs. The Rho and Rbp3 promoter regions were unmethylated in expressing photoreceptor cells and methylated in non-expressing, non-photoreceptor cells from the inner nuclear layer. A third regional hypomethylation pattern of photoreceptor-specific genes was seen in a subpopulation of non-expressing photoreceptors (Rho in cones from the Nrl -/- mouse and Opn1sw in rods). These results demonstrate that a number of photoreceptor-specific genes have cell-specific differential DNA methylation that

  17. Removal of an acid fume system contaminated with perchlorates located within hot cell

    SciTech Connect

    Rosenberg, K.E.; Henslee, S.P.; Vroman, W.R.; Krsul, J.R.; Michelbacher, J.A.; Knighton, G.C.

    1992-09-01

    An add scrubbing system located within the confines of a highly radioactive hot cell at Argonne National Laboratory-West (ANL-W) was remotely removed. The acid scrubbing system was routinely used for the dissolution of irradiated reactor fuel samples and structural materials. Perchloric acid was one of the acids used in the dissolution process and remained in the system with its inherent risks. Personnel could not enter the hot cell to perform the dismantling of the acid scabbing system due to the high radiation field and the explosion potential associated with the perchlorates. A robot was designed and built at ANL-W and used to dismantle the system without the need for personnel entry into the hot cell. The robot was also used for size reduction of removed components and loading of the removed components into waste containers.

  18. Redirecting T-cell specificity by introducing a tumor-specific chimeric antigen receptor

    PubMed Central

    Jena, Bipulendu; Dotti, Gianpietro

    2010-01-01

    Infusions of antigen-specific T cells have yielded therapeutic responses in patients with pathogens and tumors. To broaden the clinical application of adoptive immunotherapy against malignancies, investigators have developed robust systems for the genetic modification and characterization of T cells expressing introduced chimeric antigen receptors (CARs) to redirect specificity. Human trials are under way in patients with aggressive malignancies to test the hypothesis that manipulating the recipient and reprogramming T cells before adoptive transfer may improve their therapeutic effect. These examples of personalized medicine infuse T cells designed to meet patients' needs by redirecting their specificity to target molecular determinants on the underlying malignancy. The generation of clinical grade CAR+ T cells is an example of bench-to-bedside translational science that has been accomplished using investigator-initiated trials operating largely without industry support. The next-generation trials will deliver designer T cells with improved homing, CAR-mediated signaling, and replicative potential, as investigators move from the bedside to the bench and back again. PMID:20439624

  19. Estrogen deficiency heterogeneously affects tissue specific stem cells in mice

    PubMed Central

    Kitajima, Yuriko; Doi, Hanako; Ono, Yusuke; Urata, Yoshishige; Goto, Shinji; Kitajima, Michio; Miura, Kiyonori; Li, Tao-Sheng; Masuzaki, Hideaki

    2015-01-01

    Postmenopausal disorders are frequently observed in various organs, but their relationship with estrogen deficiency and mechanisms remain unclear. As tissue-specific stem cells have been found to express estrogen receptors, we examined the hypothesis that estrogen deficiency impairs stem cells, which consequently contributes to postmenopausal disorders. Six-week-old C57BL/6 female mice were ovariectomized, following which they received 17β-estradiol replacement or vehicle (control). Sham-operated mice were used as healthy controls. All mice were killed for evaluation 2 months after treatments. Compared with the healthy control, ovariectomy significantly decreased uterine weight, which was partially recovered by 17β-estradiol replacement. Ovariectomy significantly increased the numbers of c-kit-positive hematopoietic stem/progenitor cells in bone marrow, but impaired their capacity to grow mixed cell-type colonies in vitro. Estrogen replacement further increased the numbers of c-kit-positive hematopoietic stem/progenitor cells in bone marrow, without significantly affecting colony growth in vitro. The number of CD105-positive mesenchymal stem cells in bone marrow also significantly decreased after ovariectomy, but completely recovered following estrogen replacement. Otherwise, neither ovariectomy nor estrogen replacement changed the number of Pax7-positive satellite cells, which are a skeletal muscle-type stem cell. Estrogen deficiency heterogeneously affected tissue-specific stem cells, suggesting a likely and direct relationship with postmenopausal disorders. PMID:26245252

  20. A Hypersweet Protein: Removal of The Specific Negative Charge at Asp21 Enhances Thaumatin Sweetness

    PubMed Central

    Masuda, Tetsuya; Ohta, Keisuke; Ojiro, Naoko; Murata, Kazuki; Mikami, Bunzo; Tani, Fumito; Temussi, Piero Andrea; Kitabatake, Naofumi

    2016-01-01

    Thaumatin is an intensely sweet-tasting protein that elicits sweet taste at a concentration of 50 nM, a value 100,000 times larger than that of sucrose on a molar basis. Here we attempted to produce a protein with enhanced sweetness by removing negative charges on the interacting side of thaumatin with the taste receptor. We obtained a D21N mutant which, with a threshold value 31 nM is much sweeter than wild type thaumatin and, together with the Y65R mutant of single chain monellin, one of the two sweetest proteins known so far. The complex model between the T1R2-T1R3 sweet receptor and thaumatin, derived from tethered docking in the framework of the wedge model, confirmed that each of the positively charged residues critical for sweetness is close to a receptor residue of opposite charge to yield optimal electrostatic interaction. Furthermore, the distance between D21 and its possible counterpart D433 (located on the T1R2 protomer of the receptor) is safely large to avoid electrostatic repulsion but, at the same time, amenable to a closer approach if D21 is mutated into the corresponding asparagine. These findings clearly confirm the importance of electrostatic potentials in the interaction of thaumatin with the sweet receptor. PMID:26837600

  1. Removal of malaria-infected red blood cells using magnetic cell separators: A computational study.

    PubMed

    Kim, Jeongho; Massoudi, Mehrdad; Antaki, James F; Gandini, Alberto

    2012-02-15

    High gradient magnetic field separators have been widely used in a variety of biological applications. Recently, the use of magnetic separators to remove malaria-infected red blood cells (pRBCs) from blood circulation in patients with severe malaria has been proposed in a dialysis-like treatment. The capture efficiency of this process depends on many interrelated design variables and constraints such as magnetic pole array pitch, chamber height, and flow rate. In this paper, we model the malaria-infected RBCs (pRBCs) as paramagnetic particles suspended in a Newtonian fluid. Trajectories of the infected cells are numerically calculated inside a micro-channel exposed to a periodic magnetic field gradient. First-order stiff ordinary differential equations (ODEs) governing the trajectory of particles under periodic magnetic fields due to an array of wires are solved numerically using the 1(st) -5(th) order adaptive step Runge-Kutta solver. The numerical experiments show that in order to achieve a capture efficiency of 99% for the pRBCs it is required to have a longer length than 80 mm; this implies that in principle, using optimization techniques the length could be adjusted, i.e., shortened to achieve 99% capture efficiency of the pRBCs. PMID:22345827

  2. Secondary specific immune response in vitro to MSV tumor cells.

    PubMed

    Senik, A; Hebrero, F P; Levy, J P

    1975-12-15

    The interactions which occur between antigenic tumor cells and normal or immune lymphoid cells in a 3-day in vitro culture, have been studied with a murine sarcoma virus (MSV)-induced tumor. The 3H-thymidine incorporation of lymphoma cells growing in suspension, and the radioactive-chromium release of freshly sampled lymphoma cells regularly added to the culture, have been compared to determine the part played by immune lymphoid cells in cytolysis and cytostasis of the tumor-cell population. The cytolytic activity increases in the culture from day 0 to day 3. It is due, predominantly, to T-cells, and remains specific to antigens shared by MSV tumors and related lymphomas. This activity would be difficult to detect unless freshly sampled ascitic cells were used as targets, since the lymphoma cells spontaneously lose a part of their sensitivity to immune cytolysis during in vitro culture. The method used in the present experiments is a secondary chromium release test (SCRT), which measures the invitro secondary stimulation of cytotoxic T-lymphocytes (CTL) by tumor cells. In the absence of stimulatory cells, the CTL activity would have rapidly fallen in vitro. The cytostatic activity also increases during the 3 days in vitro, in parallel to the cytolytic activity: it is due to non-T-cells and remains mainly non-specific. The significance of these data for the interpretation of invitro demonstrated cell-mediated anti-tumor immune reactions is briefly discussed, as well as their relevance in the in vivo role of immune CTL. PMID:53210

  3. Type-Specific Cell Line Models for Type-Specific Ovarian Cancer Research

    PubMed Central

    Anglesio, Michael S.; Wiegand, Kimberly C.; Melnyk, Nataliya; Chow, Christine; Salamanca, Clara; Prentice, Leah M.; Senz, Janine; Yang, Winnie; Spillman, Monique A.; Cochrane, Dawn R.; Shumansky, Karey; Shah, Sohrab P.; Kalloger, Steve E.; Huntsman, David G.

    2013-01-01

    Background Ovarian carcinomas consist of at least five distinct diseases: high-grade serous, low-grade serous, clear cell, endometrioid, and mucinous. Biomarker and molecular characterization may represent a more biologically relevant basis for grouping and treating this family of tumors, rather than site of origin. Molecular characteristics have become the new standard for clinical pathology, however development of tailored type-specific therapies is hampered by a failure of basic research to recognize that model systems used to study these diseases must also be stratified. Unrelated model systems do offer value for study of biochemical processes but specific cellular context needs to be applied to assess relevant therapeutic strategies. Methods We have focused on the identification of clear cell carcinoma cell line models. A panel of 32 “ovarian cancer” cell lines has been classified into histotypes using a combination of mutation profiles, IHC mutation-surrogates, and a validated immunohistochemical model. All cell lines were identity verified using STR analysis. Results Many described ovarian clear cell lines have characteristic mutations (including ARID1A and PIK3CA) and an overall molecular/immuno-profile typical of primary tumors. Mutations in TP53 were present in the majority of high-grade serous cell lines. Advanced genomic analysis of bona-fide clear cell carcinoma cell lines also support copy number changes in typical biomarkers such at MET and HNF1B and a lack of any recurrent expressed re-arrangements. Conclusions: As with primary ovarian tumors, mutation status of cancer genes like ARID1A and TP53 and a general immuno-profile serve well for establishing histotype of ovarian cancer cell We describe specific biomarkers and molecular features to re-classify generic “ovarian carcinoma” cell lines into type specific categories. Our data supports the use of prototype clear cell lines, such as TOV21G and JHOC-5, and questions the use of SKOV3 and A

  4. Cell Specific Cytotoxicity and Uptake of Graphene Nanoribbons

    PubMed Central

    Chowdhury, Sayan Mullick; Lalwani, Gaurav; Zhang, Kevin; Yang, Jeong Yun; Neville, Kayla; Sitharaman, Balaji

    2012-01-01

    types. Additional analysis indicates that this increased uptake is the dominant cause of the significantly higher toxicity exhibited by HeLa cells. The results suggest that water-solubilized O-GNR-PEG-DSPEs have a heterogeneous cell-specific cytotoxicity, and have significantly different cytotoxicity profile compared to graphene nanoparticles prepared by the modified Hummer’s method (graphene nanoparticles prepared by oxidation of graphite, and its mechanical exfoliation) or its variations. PMID:23072942

  5. Cell specific cytotoxicity and uptake of graphene nanoribbons.

    PubMed

    Mullick Chowdhury, Sayan; Lalwani, Gaurav; Zhang, Kevin; Yang, Jeong Y; Neville, Kayla; Sitharaman, Balaji

    2013-01-01

    . Additional analysis indicates that this increased uptake is the dominant cause of the significantly higher toxicity exhibited by HeLa cells. The results suggest that water-solubilized O-GNR-PEG-DSPEs have a heterogenous cell-specific cytotoxicity, and have significantly different cytotoxicity profile compared to graphene nanoparticles prepared by the modified Hummer's method (graphene nanoparticles prepared by oxidation of graphite, and its mechanical exfoliation) or its variations. PMID:23072942

  6. Specification of epidermal cell fate in plant shoots.

    PubMed

    Takada, Shinobu; Iida, Hiroyuki

    2014-01-01

    Land plants have evolved a single layer of epidermal cells, which are characterized by mostly anticlinal cell division patterns, formation of a waterproof coat called cuticle, and unique cell types such as stomatal guard cells and trichomes. The shoot epidermis plays important roles not only to protect plants from dehydration and pathogens but also to ensure their proper organogenesis and growth control. Extensive molecular genetic studies in Arabidopsis and maize have identified a number of genes that are required for epidermal cell differentiation. However, the mechanism that specifies shoot epidermal cell fate during plant organogenesis remains largely unknown. Particularly, little is known regarding positional information that should restrict epidermal cell fate to the outermost cell layer of the developing organs. Recent studies suggested that certain members of the HD-ZIP class IV homeobox genes are possible master regulators of shoot epidermal cell fate. Here, we summarize the roles of the regulatory genes that are involved in epidermal cell fate specification and discuss the possible mechanisms that limit the expression and/or activity of the master transcriptional regulators to the outermost cell layer in plant shoots. PMID:24616724

  7. Probing Coagulation Behavior of Individual Aluminum Species for Removing Corresponding Disinfection Byproduct Precursors: The Role of Specific Ultraviolet Absorbance

    PubMed Central

    Zhao, He; Hu, Chengzhi; Zhang, Di; Liu, Huijuan; Qu, Jiuhui

    2016-01-01

    Coagulation behavior of aluminum chloride and polyaluminum chloride (PACl) for removing corresponding disinfection byproduct (DBP) precursors was discussed in this paper. CHCl3, bromine trihalomethanes (THM-Br), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) formation potential yields were correlated with specific ultraviolet absorbance (SUVA) values in different molecular weight (MW) fractions of humic substances (HS), respectively. Correlation analyses and principal component analysis were performed to examine the relationships between SUVA and different DBP precursors. To acquire more structural characters of DBP precursors and aluminum speciation, freeze-dried precipitates were analyzed by fourier transform infrared (FTIR) and C 1s, Al 2p X-ray photoelectron spectroscopy (XPS). The results indicated that TCAA precursors (no MW limits), DCAA and CHCl3 precursors in low MW fractions (MW<30 kDa) had a relatively good relations with SUVA values. These DBP precursors were coagulated more easily by in situ Al13 of AlCl3 at pH 5.0. Due to relatively low aromatic content and more aliphatic structures, THM-Br precursors (no MW limits) and CHCl3 precursors in high MW fractions (MW>30 kDa) were preferentially removed by PACl coagulation with preformed Al13 species at pH 5.0. Additionally, for DCAA precursors in high MW fractions (MW>30 kDa) with relatively low aromatic content and more carboxylic structures, the greatest removal occurred at pH 6.0 through PACl coagulation with aggregated Al13 species. PMID:26824243

  8. Probing Coagulation Behavior of Individual Aluminum Species for Removing Corresponding Disinfection Byproduct Precursors: The Role of Specific Ultraviolet Absorbance.

    PubMed

    Zhao, He; Hu, Chengzhi; Zhang, Di; Liu, Huijuan; Qu, Jiuhui

    2016-01-01

    Coagulation behavior of aluminum chloride and polyaluminum chloride (PACl) for removing corresponding disinfection byproduct (DBP) precursors was discussed in this paper. CHCl3, bromine trihalomethanes (THM-Br), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) formation potential yields were correlated with specific ultraviolet absorbance (SUVA) values in different molecular weight (MW) fractions of humic substances (HS), respectively. Correlation analyses and principal component analysis were performed to examine the relationships between SUVA and different DBP precursors. To acquire more structural characters of DBP precursors and aluminum speciation, freeze-dried precipitates were analyzed by fourier transform infrared (FTIR) and C 1s, Al 2p X-ray photoelectron spectroscopy (XPS). The results indicated that TCAA precursors (no MW limits), DCAA and CHCl3 precursors in low MW fractions (MW<30 kDa) had a relatively good relations with SUVA values. These DBP precursors were coagulated more easily by in situ Al13 of AlCl3 at pH 5.0. Due to relatively low aromatic content and more aliphatic structures, THM-Br precursors (no MW limits) and CHCl3 precursors in high MW fractions (MW>30 kDa) were preferentially removed by PACl coagulation with preformed Al13 species at pH 5.0. Additionally, for DCAA precursors in high MW fractions (MW>30 kDa) with relatively low aromatic content and more carboxylic structures, the greatest removal occurred at pH 6.0 through PACl coagulation with aggregated Al13 species. PMID:26824243

  9. Erythropoietin gene expression: developmental-stage specificity, cell-type specificity, and hypoxia inducibility.

    PubMed

    Suzuki, Norio

    2015-01-01

    Erythrocytes play an essential role in the delivery of oxygen from the lung to every organ; a decrease in erythrocytes (anemia) causes hypoxic stress and tissue damage. To maintain oxygen homeostasis in adult mammals, when the kidney senses hypoxia, it secretes an erythroid growth factor, erythropoietin (Epo), which stimulates erythropoiesis in the bone marrow. Recently, studies using genetically modified mice have shown that the in vivo expression profile of the Epo gene changes dramatically during development. The first Epo-producing cells emerge in the neural crest and neuroepithelium of mid-stage embryos and support primitive erythropoiesis in the yolk sac. Subsequently, Epo from the hepatocytes stimulates erythropoiesis in the fetal liver of later stage embryos in a paracrine manner. In fact, erythroid lineage cells comprise the largest cell population in the fetal liver, and hepatocytes are distributed among the erythroid cell clusters. Adult erythropoiesis in the bone marrow requires Epo that is secreted by renal Epo-producing cells (REP cells). REP cells are widely distributed in the renal cortex and outer medulla. Hypoxia-inducible Epo production both in hepatocytes and REP cells is controlled at the gene transcription level that is mainly mediated by the hypoxia-inducible transcription factor (HIF) pathway. These mouse studies further provide insights into the molecular mechanisms of the cell-type specific, hypoxia-inducible expression of the Epo gene, which involves multiple sets of cis- and trans-regulatory elements. PMID:25786542

  10. High specific energy, high capacity nickel-hydrogen cell design

    NASA Technical Reports Server (NTRS)

    Wheeler, James R.

    1993-01-01

    A 3.5 inch rabbit-ear-terminal nickel-hydrogen cell was designed and tested to deliver high capacity at steady discharge rates up to and including a C rate. Its specific energy yield of 60.6 wh/kg is believed to be the highest yet achieved in a slurry-process nickel-hydrogen cell, and its 10 C capacity of 113.9 AH the highest capacity yet of any type in a 3.5 inch diameter size. The cell also demonstrated a pulse capability of 180 amps for 20 seconds. Specific cell parameters and performance are described. Also covered is an episode of capacity fading due to electrode swelling and its successful recovery by means of additional activation procedures.

  11. Cell-specific activity of neprilysin 2 isoforms and enzymic specificity compared with neprilysin.

    PubMed Central

    Rose, Christiane; Voisin, Stéphanie; Gros, Claude; Schwartz, Jean-Charles; Ouimet, Tanja

    2002-01-01

    Neprilysin (NEP) 2 is a recently cloned glycoprotein displaying a high degree of sequence identity with neprilysin (EC 3.4.24.11), the prototypical member of the M13 subfamily of metalloproteases. Whereas NEP is involved in the metabolism of several bioactive peptides by plasma membranes of various cells, the enzymic properties and physiological functions of NEP2 are unknown. Here we characterize the cell-expression modalities and enzymic specificity of two alternatively spliced isoforms of NEP2 in Chinese hamster ovary and AtT20 cells. In the two cell lines, both isoforms are type II glycoproteins inserted in the endoplasmic reticulum as inactive precursors. Maturation detected by Western-blot analysis of glycosidase digests was cell-specific and more efficient in the endocrine cell line. The enzymic activity of both isoforms semi-purified from AtT20 cells reveals comparable specificities in terms of model substrates, pH optima and inhibitory patterns. NEP2 activity was compared with that of NEP regarding potencies of transition-state inhibitors, modes of hydrolysis, maximal hydrolysis rates and apparent affinities of bioactive peptides. Although all transition-state inhibitors of NEP inhibited NEP2 activity, albeit with different potencies, and many peptides were cleaved at the same amide bond by both peptidases, differences could be observed, i.e. in the hydrolysis of gonadotropin-releasing hormone and cholecystokinin, which occurred at different sites and more efficiently in the case of NEP2. Differences in cleavage of bioactive peptides, in cell-trafficking patterns and in tissue distribution indicate that NEP and NEP2 play distinct physiological roles in spite of their high degree of sequence identity. PMID:11964170

  12. Current tools for predicting cancer-specific T cell immunity.

    PubMed

    Gfeller, David; Bassani-Sternberg, Michal; Schmidt, Julien; Luescher, Immanuel F

    2016-07-01

    Tumor exome and RNA sequencing data provide a systematic and unbiased view on cancer-specific expression, over-expression, and mutations of genes, which can be mined for personalized cancer vaccines and other immunotherapies. Of key interest are tumor-specific mutations, because T cells recognizing neoepitopes have the potential to be highly tumoricidal. Here, we review recent developments and technical advances in identifying MHC class I and class II-restricted tumor antigens, especially neoantigen derived MHC ligands, including in silico predictions, immune-peptidome analysis by mass spectrometry, and MHC ligand validation by biochemical methods on T cells. PMID:27622028

  13. Tagging and Enriching Proteins Enables Cell-Specific Proteomics.

    PubMed

    Elliott, Thomas S; Bianco, Ambra; Townsley, Fiona M; Fried, Stephen D; Chin, Jason W

    2016-07-21

    Cell-specific proteomics in multicellular systems and whole animals is a promising approach to understand the differentiated functions of cells and tissues. Here, we extend our stochastic orthogonal recoding of translation (SORT) approach for the co-translational tagging of proteomes with a cyclopropene-containing amino acid in response to diverse codons in genetically targeted cells, and create a tetrazine-biotin probe containing a cleavable linker that offers a way to enrich and identify tagged proteins. We demonstrate that SORT with enrichment, SORT-E, efficiently recovers and enriches SORT tagged proteins and enables specific identification of enriched proteins via mass spectrometry, including low-abundance proteins. We show that tagging at distinct codons enriches overlapping, but distinct sets of proteins, suggesting that tagging at more than one codon enhances proteome coverage. Using SORT-E, we accomplish cell-specific proteomics in the fly. These results suggest that SORT-E will enable the definition of cell-specific proteomes in animals during development, disease progression, and learning and memory. PMID:27447048

  14. Clostridium butyricum in combination with specific immunotherapy converts antigen-specific B cells to regulatory B cells in asthmatic patients

    PubMed Central

    Liao, Hong-Ying; Tao, Li; Zhao, Jian; Qin, Jie; Zeng, Gu-Cheng; Cai, Song-Wang; Li, Yun; Zhang, Jian; Chen, Hui-Guo

    2016-01-01

    The effect of antigen specific immunotherapy (SIT) on asthma is supposed to be improved. Published data indicate that administration of probiotics alleviates allergic diseases. B cells play important roles in the pathogenesis of allergic diseases. This study aims to modulate antigen specific B cell property by the administration of Clostridium butyrate (CB) in combination with SIT. The results showed that after a 3-month treatment, the total asthma clinical score and serum specific IgE were improved in the patients treated with SIT, which was further improved in those treated with both SIT and CB, but not in those treated with CB alone. Treatment with SIT and CB increased p300 and STAT3 activation, up regulated the IL-10 gene transcription and increased the frequency of peripheral antigen specific B cells. In conclusion, administration with SIT in combination with CB converts Der p 1 specific B cells to regulatory B cells in asthma patients allergic to Der p 1. The data suggest a potential therapeutic remedy in the treatment of allergic diseases. PMID:26857726

  15. Engineered antigen-specific human regulatory T cells: immunosuppression of FVIII-specific T- and B-cell responses

    PubMed Central

    Kim, Yong Chan; Zhang, Ai-Hong; Su, Yan; Rieder, Sadiye Amcaoglu; Rossi, Robert J.; Ettinger, Ruth A.; Pratt, Kathleen P.; Shevach, Ethan M.

    2015-01-01

    Expansion of human regulatory T cells (Tregs) for clinical applications offers great promise for the treatment of undesirable immune responses in autoimmunity, transplantation, allergy, and antidrug antibody responses, including inhibitor responses in hemophilia A patients. However, polyclonal Tregs are nonspecific and therefore could potentially cause global immunosuppression. To avoid this undesirable outcome, the generation of antigen-specific Tregs would be advantageous. Herein, we report the production and properties of engineered antigen-specific Tregs, created by transduction of a recombinant T-cell receptor obtained from a hemophilia A subject’s T-cell clone, into expanded human FoxP3+ Tregs. Such engineered factor VIII (FVIII)-specific Tregs efficiently suppressed the proliferation and cytokine production of FVIII-specific T-effector cells. Moreover, studies with an HLA-transgenic, FVIII-deficient mouse model demonstrated that antibody production from FVIII-primed spleen cells in vitro were profoundly inhibited in the presence of these FVIII-specific Tregs, suggesting potential utility to treat anti-FVIII inhibitory antibody formation in hemophilia A patients. PMID:25498909

  16. T-cell regulatory mechanisms in specific immunotherapy.

    PubMed

    Jutel, Marek; Akdis, Cezmi A

    2008-01-01

    Allergen-specific immunotherapy (SIT) is the only treatment which leads to a lifelong tolerance against previously disease-causing allergens due to restoration of normal immunity against allergens. The description of T-regulatory (Treg) cells being involved in prevention of sensitization to allergens has led to great interest whether they represent a major target for allergen-SIT and whether it would be possible to manipulate Treg cells to increase its efficacy. Activationinduced cell death, anergy and/or immune response modulation by Treg cells are essential mechanisms of peripheral T-cell tolerance. There is growing evidence that anergy, tolerance and active suppression are not entirely distinct, but rather represent linked mechanisms possibly involving the same cells and multiple suppressor mechanisms. Skewing of allergen-specific effector T cells to Treg cells appears as a crucial event in the control of healthy immune response to allergens and successful allergen-SIT. The Treg cell response is characterized by abolished allergen- induced specific T-cell proliferation and suppressed Thelper (Th)1- and Th2-type cytokine secretion. In addition, mediators of allergic inflammation that trigger cAMP-associated G-protein-coupled receptors, such as histamine receptor-2, may contribute to peripheral tolerance mechanisms. The increased levels of interleukin-10 and transforming growth factor-Beta that are produced by Treg cells potently suppress IgE production, while simultaneously increasing production of non-inflammatory isotypes IgG4 and IgA, respectively. In addition, Treg cells directly or indirectly suppress effector cells of allergic inflammation such as mast cells, basophils and eosinophils. In conclusion, peripheral tolerance to allergens is controlled by multiple active suppression mechanisms. It is associated with regulation of antibody isotypes and effector cells to the direction of a healthy immune response. By the application of the recent knowledge in Treg

  17. Bioelectrochemical Chromium(VI) Removal in Plant-Microbial Fuel Cells.

    PubMed

    Habibul, Nuzahat; Hu, Yi; Wang, Yun-Kun; Chen, Wei; Yu, Han-Qing; Sheng, Guo-Ping

    2016-04-01

    Plant-microbial fuel cell (PMFC) is a renewable and sustainable energy technology that generates electricity with living plants. However, little information is available regarding the application of PMFC for the remediation of heavy metal contaminated water or soil. In this study, the potential for the removal of heavy metal Cr(VI) using PMFC was evaluated, and the performance of the PMFC at various initial Cr(VI) contents was investigated. The Cr(VI) removal efficiency could reached 99% under various conditions. Both the Cr(VI) removal rates and the removal efficiencies increased with the increasing initial Cr(VI) concentration. Furthermore, the long-term operation of the PMFC indicated that the system was stable and sustainable for Cr(VI) removal. The mass balance results and XPS analysis results demonstrate that only a small amount of soluble Cr(III) remained in the PMFC and that most Cr(III) precipitated in the form of the Cr(OH)3(s) or was adsorbed onto the electrodes. The PMFC experiments of without acetate addition also show that plants can provide carbon source for MFC through secrete root exudates and bioelectrochemical reduction of Cr(VI) was the main mechanism for the Cr(VI) removal. These results extend the application fields of PMFC and might provide a new insight for Cr(VI) removal from wastewater or soil. PMID:26962848

  18. Local Area Water Removal Analysis of a Proton Exchange Membrane Fuel Cell under Gas Purge Conditions

    PubMed Central

    Lee, Chi-Yuan; Lee, Yu-Ming; Lee, Shuo-Jen

    2012-01-01

    In this study, local area water content distribution under various gas purging conditions are experimentally analyzed for the first time. The local high frequency resistance (HFR) is measured using novel micro sensors. The results reveal that the liquid water removal rate in a membrane electrode assembly (MEA) is non-uniform. In the under-the-channel area, the removal of liquid water is governed by both convective and diffusive flux of the through-plane drying. Thus, almost all of the liquid water is removed within 30 s of purging with gas. However, liquid water that is stored in the under-the-rib area is not easy to remove during 1 min of gas purging. Therefore, the re-hydration of the membrane by internal diffusive flux is faster than that in the under-the-channel area. Consequently, local fuel starvation and membrane degradation can degrade the performance of a fuel cell that is started from cold. PMID:22368495

  19. Local area water removal analysis of a proton exchange membrane fuel cell under gas purge conditions.

    PubMed

    Lee, Chi-Yuan; Lee, Yu-Ming; Lee, Shuo-Jen

    2012-01-01

    In this study, local area water content distribution under various gas purging conditions are experimentally analyzed for the first time. The local high frequency resistance (HFR) is measured using novel micro sensors. The results reveal that the liquid water removal rate in a membrane electrode assembly (MEA) is non-uniform. In the under-the-channel area, the removal of liquid water is governed by both convective and diffusive flux of the through-plane drying. Thus, almost all of the liquid water is removed within 30 s of purging with gas. However, liquid water that is stored in the under-the-rib area is not easy to remove during 1 min of gas purging. Therefore, the re-hydration of the membrane by internal diffusive flux is faster than that in the under-the-channel area. Consequently, local fuel starvation and membrane degradation can degrade the performance of a fuel cell that is started from cold. PMID:22368495

  20. Effect of cathode electron acceptors on simultaneous anaerobic sulfide and nitrate removal in microbial fuel cell.

    PubMed

    Cai, Jing; Zheng, Ping; Mahmood, Qaisar

    2016-01-01

    The current investigation reports the effect of cathode electron acceptors on simultaneous sulfide and nitrate removal in two-chamber microbial fuel cells (MFCs). Potassium permanganate and potassium ferricyanide were common cathode electron acceptors and evaluated for substrate removal and electricity generation. The abiotic MFCs produced electricity through spontaneous electrochemical oxidation of sulfide. In comparison with abiotic MFC, the biotic MFC showed better ability for simultaneous nitrate and sulfide removal along with electricity generation. Keeping external resistance of 1,000 Ω, both MFCs showed good capacities for substrate removal where nitrogen and sulfate were the main end products. The steady voltage with potassium permanganate electrodes was nearly twice that of with potassium ferricyanide. Cyclic voltammetry curves confirmed that the potassium permanganate had higher catalytic activity than potassium ferricyanide. The potassium permanganate may be a suitable choice as cathode electron acceptor for enhanced electricity generation during simultaneous treatment of sulfide and nitrate in MFCs. PMID:26901739

  1. On-board removal of CO and other impurities in hydrogen for PEM fuel cell applications

    NASA Astrophysics Data System (ADS)

    Huang, Cunping; Jiang, Ruichun; Elbaccouch, Mohamed; Muradov, Nazim; Fenton, James M.

    Carbon monoxide (CO) in the hydrogen (H 2) stream can cause severe performance degradation for an H 2 polymer electrolyte membrane (PEM) fuel cell. The on-board removal of CO from an H 2 stream requires a process temperature less than 80 °C, and a fast reaction rate in order to minimize the reactor volume. At the present time, few technologies have been developed that meet these two requirements. This paper describes a concept of electrochemical water gas shift (EWGS) process to remove low concentration CO under ambient conditions for on-board applications. No on-board oxygen or air supply is needed for CO oxidation. Experimental work has been carried out to prove the concept of EWGS and the results indicate that the process can completely remove low level CO and improve the performance of a PEM fuel cell to the level of a pure H 2 stream. Because the EWGS electrolyzer can be modified from a humidifier for a PEM fuel cell system, no additional device is needed for the CO removal. More experimental data are needed to determine the rate of CO electrochemical removal and to explore the mechanism of the proposed process.

  2. Artesunate exerts specific cytotoxicity in retinoblastoma cells via CD71.

    PubMed

    Zhao, Fei; Wang, Han; Kunda, Patricilia; Chen, Xuemei; Liu, Qiu-Ling; Liu, Tao

    2013-09-01

    Retinoblastoma (RB) is an intraocular cancer that affects young children. There is an ongoing effort to find new agents for RB management that are effective, specific and with few side-effects. In the present study, we tested artesunate (ART), a synthetic derivative from the herbal drug artemisinin, used in the clinic for the treatment of malaria. We analyzed ART cytotoxicity in an RB cell line (RB-Y79) and in a retinal epithelial cell line (hTERT-RPE1) by flow cytometric analysis (FCM). We related the effect of ART to the expression of transferrin receptor 1 (TfR-1, also known as CD71) by knocking down CD71 with RNAi and analyzing cell cycle variables by FCM. We found that the cytotoxic action of ART is specific for RB cells in a dose-dependent manner, with low toxicity in normal retina cells. ART is more effective in RB than carboplatin with a markedly strong cytotoxic effect on carboplatin-resistant RB cells. RB had higher CD71 levels at the membrane compared to normal retinal cells. We showed that ART internalization in RB cells is dependent upon the expression of the CD71. In addition, ART blocked the cell cycle progression at the G1 phase, even at low doses, and decreased the proportion of RB cells in the S phase. In conclusion, we showed that ART is a promising drug exhibiting high selective cytotoxicity even against multidrug-resistant RB cells. Thus, we suggest that ART could be used in the treatment of RB. PMID:23818062

  3. Positive selection of self-antigen-specific CD8+ T cells by hematopoietic cells.

    PubMed

    Yamada, Hisakata; Shibata, Kensuke; Sakuraba, Koji; Fujimura, Kenjiro; Yoshikai, Yasunobu

    2013-08-01

    In contrast to thymic epithelial cells, which induce the positive selection of conventional CD8(+) T cells, hematopoietic cells (HCs) select innate CD8(+) T cells whose Ag specificity is not fully understood. Here we show that CD8(+) T cells expressing an H-Y Ag-specific Tg TCR were able to develop in mice in which only HCs expressed MHC class I, when HCs also expressed the H-Y Ag. These HC-selected self-specific CD8(+) T cells resemble innate CD8(+) T cells in WT mice in terms of the expression of memory markers and effector functions, but are phenotypically distinct from the thymus-independent CD8(+) T-cell population. The peripheral maintenance of H-Y-specific CD8(+) T cells required presentation of the self-Ag and IL-15 on HCs. HC-selected CD8(+) T cells in mice lacking the Tg TCR also showed these features. Furthermore, by using MHC class I tetramers with a male Ag peptide, we found that self-Ag-specific CD8(+) T cells in TCR non-Tg mice could develop via HC-induced positive selection, supporting results obtained from H-Y TCR Tg mice. These findings indicate the presence of self-specific CD8(+) T cells that are positively selected by HCs in the peripheral T-cell repertoire. PMID:23636825

  4. Target cell specific antibody-based photosensitizers for photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Rosenblum, Lauren T.; Mitsunaga, Makoto; Kakareka, John W.; Morgan, Nicole Y.; Pohida, Thomas J.; Choyke, Peter L.; Kobayashi, Hisataka

    2011-03-01

    In photodynamic therapy (PDT), localized monochromatic light is used to activate targeted photosensitizers (PS) to induce cellular damage through the generation of cytotoxic species such as singlet oxygen. While first-generation PS passively targeted malignancies, a variety of targeting mechanisms have since been studied, including specifically activatable agents. Antibody internalization has previously been employed as a fluorescence activation system and could potentially enable similar activation of PS. TAMRA, Rhodamine-B and Rhodamine-6G were conjugated to trastuzumab (brand name Herceptin), a humanized monoclonal antibody with specificity for the human epidermal growth factor receptor 2 (HER2), to create quenched PS (Tra-TAM, Tra-RhoB, and Tra-Rho6G). Specific PDT with Tra-TAM and Tra-Rho6G, which formed covalently bound H-dimers, was demonstrated in HER2+ cells: Minimal cell death (<6%) was observed in all treatments of the HER2- cell line (BALB/3T3) and in treatments the HER2+ cell line (3T3/HER2) with light or trastuzumab only. There was significant light-induced cell death in HER2 expressing cells using Tra-TAM (3% dead without light, 20% at 50 J/cm2, 46% at 100 J/cm2) and Tra-Rho6G (5% dead without light, 22% at 50 J/cm2, 46% at 100 J/cm2). No efficacy was observed in treatment with Tra-RhoB, which was also non-specifically taken up by BALB/3T3 cells and which had weaker PS-antibody interactions (as demonstrated by visualization of protein and fluorescence on SDS-PAGE).

  5. Micro-magnet arrays for specific single bacterial cell positioning

    NASA Astrophysics Data System (ADS)

    Pivetal, Jérémy; Royet, David; Ciuta, Georgeta; Frenea-Robin, Marie; Haddour, Naoufel; Dempsey, Nora M.; Dumas-Bouchiat, Frédéric; Simonet, Pascal

    2015-04-01

    In various contexts such as pathogen detection or analysis of microbial diversity where cellular heterogeneity must be taken into account, there is a growing need for tools and methods that enable microbiologists to analyze bacterial cells individually. One of the main challenges in the development of new platforms for single cell studies is to perform precise cell positioning, but the ability to specifically target cells is also important in many applications. In this work, we report the development of new strategies to selectively trap single bacterial cells upon large arrays, based on the use of micro-magnets. Escherichia coli bacteria were used to demonstrate magnetically driven bacterial cell organization. In order to provide a flexible approach adaptable to several applications in the field of microbiology, cells were magnetically and specifically labeled using two different strategies, namely immunomagnetic labeling and magnetic in situ hybridization. Results show that centimeter-sized arrays of targeted, isolated bacteria can be successfully created upon the surface of a flat magnetically patterned hard magnetic film. Efforts are now being directed towards the integration of a detection tool to provide a complete micro-system device for a variety of microbiological applications.

  6. Factors affecting the performance of microbial fuel cells for sulfur pollutants removal.

    PubMed

    Zhao, Feng; Rahunen, Nelli; Varcoe, John R; Roberts, Alexander J; Avignone-Rossa, Claudio; Thumser, Alfred E; Slade, Robert C T

    2009-03-15

    A microbial fuel cell (MFC) has been developed for removal of sulfur-based pollutants and can be used for simultaneous wastewater treatment and electricity generation. This fuel cell uses an activated carbon cloth+carbon fibre veil composite anode, air-breathing dual cathodes and the sulfate-reducing species Desulfovibrio desulfuricans. 1.16gdm(-3) sulfite and 0.97gdm(-3) thiosulfate were removed from the wastewater at 22 degrees C, representing sulfite and thiosulfate removal conversions of 91% and 86%, respectively. The anode potential was controlled by the concentration of sulfide in the compartment. The performance of the cathode assembly was affected by the concentration of protons in the cation-exchanging ionomer with which the electrocatalyst is co-bound at the three-phase (air, catalyst and support) boundary. PMID:19022647

  7. Analysis of a heat recirculating cooler for fuel gas sulfur removal in solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Richards, Geo. A.; Berry, David A.; Freed, Adam

    When using conventional fossil fuels, most fuel cell systems require sulfur removal as part of their fuel processing. A novel approach to enable conventional sulfur removal in high-temperature fuel processing is presented. Using established principles from heat-recirculating combustors, it is suggested that high-temperature syngas can be momentarily cooled to conditions that would permit conventional sulfur removal to be carried out at relatively low temperatures. The recirculated heat is then used to heat the gas back to conditions that are minimally less than the original temperature. A model for evaluating the performance of this concept is presented, and calculations suggest that relative to fuel cell applications, reasonable physical dimensions can be expected in actual applications. For high-pressure syngas (i.e., coal gasification), the physical dimensions will rise with the operating pressure.

  8. Cell adhesion. Competition between nonspecific repulsion and specific bonding.

    PubMed Central

    Bell, G I; Dembo, M; Bongrand, P

    1984-01-01

    We develop a thermodynamic calculus for the modeling of cell adhesion. By means of this approach, we are able to compute the end results of competition between the formation of specific macromolecular bridges and nonspecific repulsion arising from electrostatic forces and osmotic (steric stabilization) forces. Using this calculus also allows us to derive in a straightforward manner the effects of cell deformability, the Young's modulus for stretching of bridges, diffusional mobility of receptors, heterogeneity of receptors, variation in receptor number, and the strength of receptor-receptor binding. The major insight that results from our analysis concerns the existence and characteristics of two phase transitions corresponding, respectively, to the onset of stable cell adhesion and to the onset of maximum cell-cell or cell-substrate contact. We are also able to make detailed predictions of the equilibrium contact area, equilibrium number of bridges, and the cell-cell or cell-substrate separation distance. We illustrate how our approach can be used to improve the analysis of experimental data, by means of two concrete examples. PMID:6743742

  9. Routine detection of Epstein-Barr virus specific T-cells in the peripheral blood by flow cytometry

    NASA Technical Reports Server (NTRS)

    Crucian, B. E.; Stowe, R. P.; Pierson, D. L.; Sams, C. F.

    2001-01-01

    The ability to detect cytomegalovirus-specific T-cells (CD4(+)) in the peripheral blood by flow cytometry has been recently described by Picker et al. In this method, cells are incubated with viral antigen and responding (cytokine producing) T-cells are then identified by flow cytometry. To date, this technique has not been reliably used to detect Epstein-Barr virus (EBV)-specific T-cells primarily due to the superantigen/mitogenic properties of the virus which non-specifically activate T-cells. By modifying culture conditions under which the antigens are presented, we have overcome this limitation and developed an assay to detect and quantitate EBV-specific T-cells. The detection of cytokine producing T-cells by flow cytometry requires an extremely strong signal (such as culture in the presence of PMA and ionomycin). Our data indicate that in modified culture conditions (early removal of viral antigen) the non-specific activation of T-cells by EBV is reduced, but antigen presentation will continue uninhibited. Using this method, EBV-specific T-cells may be legitimately detected using flow cytometry. No reduction in the numbers of antigen-specific T-cells was observed by the early removal of target antigen when verified using cytomegalovirus antigen (a virus with no non-specific T-cell activation properties). In EBV-seropositive individuals, the phenotype of the EBV-specific cytokine producing T-cells was evaluated using four-color flow cytometry and found to be CD45(+), CD3(+), CD4(+), CD45RA(-), CD69(+), CD25(-). This phenotype indicates the stimulation of circulating previously unactivated memory T-cells. No cytokine production was observed in CD4(+) T-cells from EBV-seronegative individuals, confirming the specificity of this assay. In addition, the use of four color cytometry (CD45, CD3, CD69, IFNgamma/IL-2) allows the total quantitative assessment of EBV-specific T-cells while monitoring the interference of EBV non-specific mitogenic activity. This method may

  10. Development and qualification of a novel virus removal filter for cell culture applications.

    PubMed

    Liu, S; Carroll, M; Iverson, R; Valera, C; Vennari, J; Turco, K; Piper, R; Kiss, R; Lutz, H

    2000-01-01

    Commercial bioreactors employing mammalian cell cultures to express biological or pharmaceutical products can become contaminated with adventitious viruses. The high expense of such a contamination can be reduced by passing all gases and fluids feeding the bioreactor through virus inactivation or removal steps, which act as viral barriers around the bioreactor. A novel virus barrier filter has been developed for removing viruses from serum-free cell culture media. This filter removes the 20 nm minute virus of mice by >3 log reduction value (LRV), the 28 nm bacteriophage PhiX174 by >4.5 LRV, the mycoplasma Acholeplasma laidlawii by > or =8.8 LRV, and the bacteria Brevundimonas diminuta by > or =9.2 LRV. Robust removal occurs primarily by size exclusion as demonstrated over a wide range of feedstocks and operating conditions. The filtered media are indistinguishable from unfiltered media in growth of cells to high densities, maintenance of cell viability, and productivity in expressing protein product. Insulin and transferrin show high passage through the filter. The virus barrier filter can be autoclaved. The relatively high membrane permeability enables the use of a moderate filtration area. PMID:10835245

  11. Acid Gas Removal by Customized Sorbents for Integrated Gasification Fuel Cell Systems

    SciTech Connect

    Kapfenberger, J.; Sohnemann, J.; Schleitzer, D.; Loewen, A.

    2002-09-20

    In order to reduce exergy losses, gas cleaning at high temperatures is favored in IGFC systems. As shown by thermodynamic data, separation efficiencies of common sorbents decrease with increasing temperature. Therefore, acid gas removal systems have to be developed for IGFC applications considering sorbent capacity, operation temperature, gasification feedstock composition and fuel cell threshold values.

  12. Surgical removal of a mammary adenocarcinoma and a granulosa cell tumor in an African pygmy hedgehog

    PubMed Central

    Wellehan, James F.X.; Southorn, Erin; Smith, Dale A.; Taylor, Michael

    2003-01-01

    A 3-year-old, female African pygmy hedgehog (Atelerix albiventris) was referred with a history of hematuria. Hyperglycemia and glucosuria were found at presentation. Mammary adenocarcinoma and a granulosa cell tumor were found and removed surgically. Glucosuria and hematuria resolved, and the hedgehog has done well for 10 mo postoperatively. PMID:12677695

  13. Surgical removal of a mammary adenocarcinoma and a granulosa cell tumor in an African pygmy hedgehog.

    PubMed

    Wellehan, James F X; Southorn, Erin; Smith, Dale A; Taylor, W Michael

    2003-03-01

    A 3-year-old, female African pygmy hedgehog (Atelerix albiventris) was referred with a history of hematuria. Hyperglycemia and glucosuria were found at presentation. Mammary adenocarcinoma and a granulosa cell tumor were found and removed surgically. Glucosuria and hematuria resolved, and the hedgehog has done well for 10 mo postoperatively. PMID:12677695

  14. Pilot test specific test plan for the removal of arsenic Socorro, New Mexico.

    SciTech Connect

    Collins, Sue S.; Aragon, Malynda Jo; Everett, Randy L.; Siegel, Malcolm Dean; Aragon, Alicia R.; Dwyer, Brian P.; Marbury, Justin Luke

    2006-03-01

    Sandia National Laboratories (SNL) is conducting pilot scale evaluations of the performance and cost of innovative drinking water treatment technologies designed to meet the new arsenic maximum contaminant level (MCL) of 10 {micro}g/L (effective January 2006). As currently envisioned, pilots tests may include multiple phases. Phase I tests will involve side-by-side comparisons of several commercial technologies primarily using design parameters suggested by the Vendors. Subsequent tests (Phase II) may involve repeating some of the original tests, testing the same commercial technologies under different conditions and testing experimental technologies or additional commercial technologies. This Pilot Test Specific Test Plan (PTSTP) was written for Phase I of the Socorro Springs Pilot. The objectives of Phase I include evaluation of the treatment performance of five adsorptive media under ambient pH conditions (approximately 8.0) and assessment of the effect of contact time on the performance of one of the media. Addenda to the PTSTP may be written to cover Phase II studies and supporting laboratory studies. The Phase I demonstration began in the winter of 2004 and will last approximately 9 months. The information from the test will help the City of Socorro choose the best arsenic treatment technology for the Socorro Springs well. The pilot demonstration is a project of the Arsenic Water Technology Partnership program, a partnership between the American Water Works Association (AWWA) Research Foundation, SNL, and WERC (A Consortium for Environmental Education and Technology Development).

  15. High efficiency cell-specific targeting of cytokine activity

    NASA Astrophysics Data System (ADS)

    Garcin, Geneviève; Paul, Franciane; Staufenbiel, Markus; Bordat, Yann; van der Heyden, José; Wilmes, Stephan; Cartron, Guillaume; Apparailly, Florence; de Koker, Stefaan; Piehler, Jacob; Tavernier, Jan; Uzé, Gilles

    2014-01-01

    Systemic toxicity currently prevents exploiting the huge potential of many cytokines for medical applications. Here we present a novel strategy to engineer immunocytokines with very high targeting efficacies. The method lies in the use of mutants of toxic cytokines that markedly reduce their receptor-binding affinities, and that are thus rendered essentially inactive. Upon fusion to nanobodies specifically binding to marker proteins, activity of these cytokines is selectively restored for cell populations expressing this marker. This ‘activity-by-targeting’ concept was validated for type I interferons and leptin. In the case of interferon, activity can be directed to target cells in vitro and to selected cell populations in mice, with up to 1,000-fold increased specific activity. This targeting strategy holds promise to revitalize the clinical potential of many cytokines.

  16. Detecting Antigen-Specific T Cell Responses: From Bulk Populations to Single Cells

    PubMed Central

    Phetsouphanh, Chansavath; Zaunders, John James; Kelleher, Anthony Dominic

    2015-01-01

    A new generation of sensitive T cell-based assays facilitates the direct quantitation and characterization of antigen-specific T cell responses. Single-cell analyses have focused on measuring the quality and breadth of a response. Accumulating data from these studies demonstrate that there is considerable, previously-unrecognized, heterogeneity. Standard assays, such as the ICS, are often insufficient for characterization of rare subsets of cells. Enhanced flow cytometry with imaging capabilities enables the determination of cell morphology, as well as the spatial localization of the protein molecules within a single cell. Advances in both microfluidics and digital PCR have improved the efficiency of single-cell sorting and allowed multiplexed gene detection at the single-cell level. Delving further into the transcriptome of single-cells using RNA-seq is likely to reveal the fine-specificity of cellular events such as alternative splicing (i.e., splice variants) and allele-specific expression, and will also define the roles of new genes. Finally, detailed analysis of clonally related antigen-specific T cells using single-cell TCR RNA-seq will provide information on pathways of differentiation of memory T cells. With these state of the art technologies the transcriptomics and genomics of Ag-specific T cells can be more definitively elucidated. PMID:26274954

  17. Molecular targeting of intracellular compartments specifically in cancer cells.

    PubMed

    Pandya, Hetal; Gibo, Denise M; Debinski, Waldemar

    2010-05-01

    We have implemented a strategy in which a genetically engineered, single-chain protein specifically recognizes cancer cells and is trafficked to a targeted subcellular compartment, such as the nucleus. The recombinant protein termed IL-13.E13K-D2-NLS has a triple functional property: (1) it binds a cancer-associated receptor, interleukin 13 receptor alpha 2 (IL-13Rα2), using modified IL-13 ligand, IL-13.E13K; (2) it exports its C-terminal portion out of the endosomal compartment using Pseudomonas aeruginosa exotoxin A (PE) translocation domain (D2); and (3) it travels to and accumulates in the nucleus guided by the nuclear localization signal (NLS). Here, we have demonstrated that this protein is transported into the brain tumor cells' nucleus, using 3 different methods of protein conjugation to dyes for the purpose of direct visualization of the protein's intracellular trafficking. IL-13.E13K-D2-NLS, and not the controls such as IL-13.E13K-D2, IL-13.E13K-NLS, or IL-13.E13K, accumulated in nuclei very efficiently, which increased with the time the cells were exposed to the protein. Also, IL-13.E13K-D2-NLS did not exhibit nuclear transport in cells with low expression levels of IL-13Rα2. Thus, it is possible to recognize cancer cells through their specific receptors and deliver a conjugated protein that travels specifically to the nucleus. Hence, our molecular targeting strategy succeeded in generating a single-chain proteinaceous agent capable of delivering drugs/labels needed to be localized to the cells' nuclei or potentially any other subcellular compartment, for their optimal efficacy or ability to exert their specific action. PMID:20740056

  18. Probing Xylan-Specific Raman Bands for Label-Free Imaging Xylan in Plant Cell Wall

    SciTech Connect

    Zeng, Yining; Yarbrough, John M.; Mittal, Ashutosh; Tucker, Melvin P.; Vinzant, Todd; Himmel, Michael E.

    2015-06-15

    Xylan constitutes a significant portion of biomass (e.g. 22% in corn stover used in this study). Xylan is also an important source of carbohydrates, besides cellulose, for renewable and sustainable energy applications. Currently used method for the localization of xylan in biomass is to use fluorescence confocal microscope to image the fluorescent dye labeled monoclonal antibody that specifically binds to xylan. With the rapid adoption of the Raman-based label-free chemical imaging techniques in biology, identifying Raman bands that are unique to xylan would be critical for the implementation of the above label-free techniques for in situ xylan imaging. Unlike lignin and cellulose that have long be assigned fingerprint Raman bands, specific Raman bands for xylan remain unclear. The major challenge is the cellulose in plant cell wall, which has chemical units highly similar to that of xylan. Here we report using xylanase to specifically remove xylan from feedstock. Under various degree of xylan removal, with minimum impact to other major cell wall components, i.e. lignin and cellulose, we have identified Raman bands that could be further tested for chemical imaging of xylan in biomass in situ.

  19. Red blood cells do not contribute to removal of K+ released from exhaustively working forearm muscle.

    PubMed

    Maassen, N; Foerster, M; Mairbäurl, H

    1998-07-01

    K+ released from exercising muscle via K+ channels needs to be removed from the interstitium into the blood to maintain high muscle cell membrane potential and allow normal muscle contractility. Uptake by red blood cells has been discussed as one mechanism that would also serve to regulate red blood cell volume, which was found to be constant despite increased plasma osmolality and K+ concentration ([K+pl]). We evaluated exercise-related changes in [K+pl], pH, osmolality, mean cellular Hb concentration, cell water, and red blood cell K+ concentration during exhaustive handgrip exercise. Unidirectional 86Rb+ (K+) uptake by red blood cells was measured in media with elevated extracellular K+, osmolarity, and catecholamines to simulate particularly those exercise-related changes in plasma composition that are known to stimulate K+ uptake. During exercise [K+pl] increased from 4.4 +/- 0.7 to 7.1 +/- 0.5 mmol/l plasma water and red blood cell K+ concentration increased from 137.2 +/- 6.0 to 144.6 +/- 4.6 mmol/l cell water (P cells was increased by approximately 20% on stimulation, caused by activation of the Na+-K+ pump and Na+-K+-2Cl- cotransport. Results indicate the K+ content of red blood cells did not change as cells passed the exhaustively exercising forearm muscle despite the elevated [K+pl]. The tendency for an increase in intracellular K+ concentration was due to a slight, although statistically not significant, decrease in red blood cell volume. K+ uptake, although elevated, was too small to move significant amounts of K+ into red blood cells. Our results suggest that red blood cells do not contribute to the removal of K+ released from muscle and do not regulate their volume by K+ uptake during exhaustive forearm exercise. PMID:9655793

  20. Dimeric HER2-specific affibody molecules inhibit proliferation of the SKBR-3 breast cancer cell line

    SciTech Connect

    Ekerljung, Lina Lindborg, Malin; Gedda, Lars; Frejd, Fredrik Y; Carlsson, Joergen; Lennartsson, Johan

    2008-12-12

    HER2-specific affibody molecules in different formats have previously been shown to be useful tumor targeting agents for radionuclide-based imaging and therapy applications, but their biological effect on tumor cells is not well known. In this study, two dimeric ((Z{sub HER2:4}){sub 2} and (Z{sub HER2:342}){sub 2}) and one monomeric (Z{sub HER2:342}) HER2-specific affibody molecules are investigated with respect to biological activity. Both (Z{sub HER2:4}){sub 2} and (Z{sub HER2:342}){sub 2} were found to decrease the growth rate of SKBR-3 cells to the same extent as the antibody trastuzumab. When the substances were removed, the cells treated with the dimeric affibody molecules continued to be growth suppressed while the cells treated with trastuzumab immediately resumed normal proliferation. The effects of Z{sub HER2:342} were minor on both proliferation and cell signaling. The dimeric (Z{sub HER2:4}){sub 2} and (Z{sub HER2:342}){sub 2} both reduced growth of SKBR-3 cells and may prove therapeutically useful either by themselves or as carriers of radionuclides or other cytotoxic agents.

  1. Automated Analysis of Cell Cycle Phase-Specific DNA Damage Reveals Phase-Specific Differences in Cell Sensitivity to Etoposide.

    PubMed

    Luzhin, Artem V; Velichko, Artem K; Razin, Sergey V; Kantidze, Omar L

    2016-10-01

    The comet assay is one of the most widely used approaches for detecting DNA damage; generally, it provides information on the cell population-averaged level of DNA damage. Here, we present an automatic technique for easy measurement of standard comet characteristics and an annotation of the cell cycle phase of each comet. The approach includes the modified neutral comet assay and a pipeline for CellProfiler software designed to analyze DNA damage-related characteristics and annotate the cell cycle phase of each comet. Using this technique we have performed cell cycle phase-specific analysis of DNA damage induced by the topoisomerase II poison etoposide and have shown that the sensitivity of cells to this drug dramatically differed according to their cell cycle phase. It became evident from our results that the proposed protocol provides important additional information that often remains hidden in a standard comet analysis of an asynchronous cell population. J. Cell. Biochem. 117: 2209-2214, 2016. © 2016 Wiley Periodicals, Inc. PMID:27240930

  2. Extracellular Vesicles from Ovarian Carcinoma Cells Display Specific Glycosignatures

    PubMed Central

    Gomes, Joana; Gomes-Alves, Patrícia; Carvalho, Sofia B.; Peixoto, Cristina; Alves, Paula M.; Altevogt, Peter; Costa, Julia

    2015-01-01

    Cells release vesicles to the extracellular environment with characteristic nucleic acid, protein, lipid, and glycan composition. Here we have isolated and characterized extracellular vesicles (EVs) and total cell membranes (MBs) from ovarian carcinoma OVMz cells. EVs were enriched in specific markers, including Tsg101, CD63, CD9, annexin-I, and MBs contained markers of cellular membrane compartments, including calnexin, GRASP65, GS28, LAMP-1, and L1CAM. The glycoprotein galectin-3 binding protein (LGALS3BP) was strongly enriched in EVs and it contained sialylated complex N-glycans. Lectin blotting with a panel of lectins showed that EVs had specific glycosignatures relative to MBs. Furthermore, the presence of glycoproteins bearing complex N-glycans with α2,3-linked sialic acid, fucose, bisecting-GlcNAc and LacdiNAc structures, and O-glycans with the T-antigen were detected. The inhibition of N-glycosylation processing from high mannose to complex glycans using kifunensine caused changes in the composition of EVs and induced a decrease of several glycoproteins. In conclusion, the results showed that glycosignatures of EVs were specific and altered glycosylation within the cell affected the composition and/or dynamics of EVs release. Furthermore, the identified glycosignatures of EVs could provide novel biomarkers for ovarian cancer. PMID:26248080

  3. Targeting vault nanoparticles to specific cell surface receptors.

    PubMed

    Kickhoefer, Valerie A; Han, Muri; Raval-Fernandes, Sujna; Poderycki, Michael J; Moniz, Raymond J; Vaccari, Dana; Silvestry, Mariena; Stewart, Phoebe L; Kelly, Kathleen A; Rome, Leonard H

    2009-01-27

    As a naturally occurring nanocapsule abundantly expressed in nearly all-eukaryotic cells, the barrel-shaped vault particle is perhaps an ideal structure to engineer for targeting to specific cell types. Recombinant vault particles self-assemble from 96 copies of the major vault protein (MVP), have dimensions of 72.5 x 41 nm, and have a hollow interior large enough to encapsulate hundreds of proteins. In this study, three different tags were engineered onto the C-terminus of MVP: an 11 amino acid epitope tag, a 33 amino acid IgG-binding peptide, and the 55 amino acid epidermal growth factor (EGF). These modified vaults were produced using a baculovirus expression system. Our studies demonstrate that recombinant vaults assembled from MVPs containing C-terminal peptide extensions display these tags at the top and bottom of the vault on the outside of the particle and can be used to specifically bind the modified vaults to epithelial cancer cells (A431) via the epidermal growth factor receptor (EGFR), either directly (EGF modified vaults) or as mediated by a monoclonal antibody (anti-EGFR) bound to recombinant vaults containing the IgG-binding peptide. The ability to target vaults to specific cells represents an essential advance toward using recombinant vaults as delivery vehicles. PMID:19206245

  4. Redirecting T Cell Specificity Using T Cell Receptor Messenger RNA Electroporation.

    PubMed

    Koh, Sarene; Shimasaki, Noriko; Bertoletti, Antonio

    2016-01-01

    Autologous T lymphocytes genetically modified to express T cell receptors or chimeric antigen receptors have shown great promise in the treatment of several cancers, including melanoma and leukemia. In addition to tumor-associated antigens and tumor-specific neoantigens, tumors expressing viral peptides can also be recognized by specific T cells and are attractive targets for cell therapy. Hepatocellular carcinoma cells often have hepatitis B virus DNA integration and can be targeted by hepatitis B virus-specific T cells. Here, we describe a method to engineer hepatitis B virus-specific T cell receptors in primary human T lymphocytes based on electroporation of hepatitis B virus T cell receptor messenger RNA. This method can be extended to a large scale therapeutic T cell production following current good manufacturing practice compliance and is applicable to the redirection of T lymphocytes with T cell receptors of other virus specificities such as Epstein-Barr virus, cytomegalovirus, and chimeric receptors specific for other antigens expressed on cancer cells. PMID:27236807

  5. Cell-specific synaptic plasticity induced by network oscillations

    PubMed Central

    Zarnadze, Shota; Bäuerle, Peter; Santos-Torres, Julio; Böhm, Claudia; Schmitz, Dietmar; Geiger, Jörg RP

    2016-01-01

    Gamma rhythms are known to contribute to the process of memory encoding. However, little is known about the underlying mechanisms at the molecular, cellular and network levels. Using local field potential recording in awake behaving mice and concomitant field potential and whole-cell recordings in slice preparations we found that gamma rhythms lead to activity-dependent modification of hippocampal networks, including alterations in sharp wave-ripple complexes. Network plasticity, expressed as long-lasting increases in sharp wave-associated synaptic currents, exhibits enhanced excitatory synaptic strength in pyramidal cells that is induced postsynaptically and depends on metabotropic glutamate receptor-5 activation. In sharp contrast, alteration of inhibitory synaptic strength is independent of postsynaptic activation and less pronounced. Further, we found a cell type-specific, directionally biased synaptic plasticity of two major types of GABAergic cells, parvalbumin- and cholecystokinin-expressing interneurons. Thus, we propose that gamma frequency oscillations represent a network state that introduces long-lasting synaptic plasticity in a cell-specific manner. DOI: http://dx.doi.org/10.7554/eLife.14912.001 PMID:27218453

  6. Cell-specific synaptic plasticity induced by network oscillations.

    PubMed

    Zarnadze, Shota; Bäuerle, Peter; Santos-Torres, Julio; Böhm, Claudia; Schmitz, Dietmar; Geiger, Jörg Rp; Dugladze, Tamar; Gloveli, Tengis

    2016-01-01

    Gamma rhythms are known to contribute to the process of memory encoding. However, little is known about the underlying mechanisms at the molecular, cellular and network levels. Using local field potential recording in awake behaving mice and concomitant field potential and whole-cell recordings in slice preparations we found that gamma rhythms lead to activity-dependent modification of hippocampal networks, including alterations in sharp wave-ripple complexes. Network plasticity, expressed as long-lasting increases in sharp wave-associated synaptic currents, exhibits enhanced excitatory synaptic strength in pyramidal cells that is induced postsynaptically and depends on metabotropic glutamate receptor-5 activation. In sharp contrast, alteration of inhibitory synaptic strength is independent of postsynaptic activation and less pronounced. Further, we found a cell type-specific, directionally biased synaptic plasticity of two major types of GABAergic cells, parvalbumin- and cholecystokinin-expressing interneurons. Thus, we propose that gamma frequency oscillations represent a network state that introduces long-lasting synaptic plasticity in a cell-specific manner. PMID:27218453

  7. CatacLysMic specificity when targeting myeloid cells?

    PubMed

    Blank, Thomas; Prinz, Marco

    2016-06-01

    The antibacterial enzyme lysozyme M (LysM) encoded by the Lyz2 gene is broadly expressed in myeloblasts, macrophages, and neutrophils, and thus has been used for a long time as a cell-specific marker for myeloid cells in mice. In order to delete loxP-site flanked genes in myeloid cells, a Cre-recombinase (Cre) expressing mouse line was created by inserting Cre-coding sequence into the translational start site of the LysM gene. In this issue of the European Journal of Immunology [2016. 46: 1529-1532], Orthgiess et al. verify, with the help of tdTomato and YFP reporter mouse lines, LysM-driven recombination. Unexpectedly, the authors also describe major expression of the tdTomato reporter protein in brain neurons of the central nervous system (CNS), with only a very small percentage of gene recombination in myeloid cells of the brain, called microglia. These findings cause justified concerns regarding the efficient and specific targeting of microglia and peripheral myeloid cells using LysM-Cre mice and should stimulate thoughts on conclusions drawn from past experiments on the diseased CNS employing this Cre/loxP-deleter line. PMID:27198084

  8. [Inhibition of adenovirus reproduction in cell culture by specific antibodies].

    PubMed

    Povnytsia, O Iu; Nosach, L M; Zhovnovata, V L; Zahorodnia, S D; Vantsak, N P; Tokarchuk, L V; Polishchuk, O M; Diachenko, N S

    2009-01-01

    The capacity of specific antibodies to inhibit the reproduction of homo- and heterologous adenoviruses in Hela cell added to culture medium after virus adsorption was studied. The inhibiting effect of polyclonal antivirus and monospecific antihexone antibodies to homo- and heterologous adenoviruses was shown. The effect was more expressed when using antibodies to homologous antibodies. The intensity of inhibition depended on antibodies concentration in the medium and infecting dose of the virus. Essential reduction of the quantity of infected cells and a decrease of the titer of adenovirus synthesized in the presence of homo- and heterologous antibodies was shown but adenovirus reproduction was not inhibited completely. PMID:19663330

  9. Potential cell-specific functions of CXCR4 in atherosclerosis.

    PubMed

    Weber, Christian; Döring, Yvonne; Noels, Heidi

    2016-05-10

    The chemokine CXCL12 and its receptor CXCR4 form an important axis contributing to cellular functions in homeostasis and disease. In addition, the atypical CXCL12 receptor CXCR7 may shape the availability and function of CXCL12. Further to their role through progenitor cell mobilization, CXCL12 and CXCR4 may affect native atherogenesis by modifying atherosclerosis-relevant cellular functions. This short review intends to provide a concise summary of current knowledge with regards to cell-specific functions of CXCL12 and its receptors CXCR4 and CXCR7 with potential implications for the initiation and progression of atherosclerosis. PMID:25586789

  10. A chemical lift-off process: removing non-specific adsorption in an electrochemical Epstein-Barr virus immunoassay.

    PubMed

    Stratmann, Lutz; Gebala, Magdalena; Schuhmann, Wolfgang

    2013-07-22

    Upon contact of sensor surfaces with complex biological samples containing a variety of different proteins, non-specific adsorption hampers the high-sensitive detection of the analyte in question. To substantially decrease the impact of non-specific adsorption at thiol-based self-assembled monolayers, a chemical lift-off process is introduced. A sequence of local hydrolysis of isooctyl 3-mercaptopropionate, covalent binding of an antigen against the Epstein-Barr virus (EBV), stepwise incubation with a serum sample possibly containing the EBV antibody and an enzyme-labeled anti-human antibody is completed with a lift-off by integral hydrolysis of the remaining ester groups at the self-assembled monolayer. The cleavage of the ester removes any non-specifically bound protein during a following stringent washing step. The substantial improvement of the detection limit of an electrochemical immunoassay against EBV using native recombinant antigens, their immobilization after local deprotection using a scanning electrochemical microscope (SECM) and the local read-out using the generator-collector mode of SECM with redox cycling amplification demonstrates the successful application of the proposed lift-off procedure. PMID:23681905

  11. Site-Specific Genome Engineering in Human Pluripotent Stem Cells.

    PubMed

    Merkert, Sylvia; Martin, Ulrich

    2016-01-01

    The possibility to generate patient-specific induced pluripotent stem cells (iPSCs) offers an unprecedented potential of applications in clinical therapy and medical research. Human iPSCs and their differentiated derivatives are tools for diseases modelling, drug discovery, safety pharmacology, and toxicology. Moreover, they allow for the engineering of bioartificial tissue and are promising candidates for cellular therapies. For many of these applications, the ability to genetically modify pluripotent stem cells (PSCs) is indispensable, but efficient site-specific and safe technologies for genetic engineering of PSCs were developed only recently. By now, customized engineered nucleases provide excellent tools for targeted genome editing, opening new perspectives for biomedical research and cellular therapies. PMID:27347935

  12. Epigenetic control of cell specification during female gametogenesis.

    PubMed

    Armenta-Medina, Alma; Demesa-Arévalo, Edgar; Vielle-Calzada, Jean-Philippe

    2011-06-01

    In flowering plants, the formation of gametes depends on the differentiation of cellular precursors that divide meiotically before giving rise to a multicellular gametophyte. The establishment of this gametophytic phase presents an opportunity for natural selection to act on the haploid plant genome by means of epigenetic mechanisms that ensure a tight regulation of plant reproductive development. Despite this early acting selective pressure, there are numerous examples of naturally occurring developmental alternatives that suggest a flexible regulatory control of cell specification and subsequent gamete formation in flowering plants. In this review, we discuss recent findings indicating that epigenetic mechanisms related to the activity of small RNA pathways prevailing during ovule formation play an essential role in cell specification and genome integrity. We also compare these findings to small RNA pathways acting during gametogenesis in animals and discuss their implications for the understanding of the mechanisms that control the establishment of the female gametophytic lineage during both sexual reproduction and apomixis. PMID:21484604

  13. Site-Specific Genome Engineering in Human Pluripotent Stem Cells

    PubMed Central

    Merkert, Sylvia; Martin, Ulrich

    2016-01-01

    The possibility to generate patient-specific induced pluripotent stem cells (iPSCs) offers an unprecedented potential of applications in clinical therapy and medical research. Human iPSCs and their differentiated derivatives are tools for diseases modelling, drug discovery, safety pharmacology, and toxicology. Moreover, they allow for the engineering of bioartificial tissue and are promising candidates for cellular therapies. For many of these applications, the ability to genetically modify pluripotent stem cells (PSCs) is indispensable, but efficient site-specific and safe technologies for genetic engineering of PSCs were developed only recently. By now, customized engineered nucleases provide excellent tools for targeted genome editing, opening new perspectives for biomedical research and cellular therapies. PMID:27347935

  14. Identifying States along the Hematopoietic Stem Cell Differentiation Hierarchy with Single Cell Specificity via Raman Spectroscopy.

    PubMed

    Ilin, Yelena; Choi, Ji Sun; Harley, Brendan A C; Kraft, Mary L

    2015-11-17

    A major challenge for expanding specific types of hematopoietic cells ex vivo for the treatment of blood cell pathologies is identifying the combinations of cellular and matrix cues that direct hematopoietic stem cells (HSC) to self-renew or differentiate into cell populations ex vivo. Microscale screening platforms enable minimizing the number of rare HSCs required to screen the effects of numerous cues on HSC fate decisions. These platforms create a strong demand for label-free methods that accurately identify the fate decisions of individual hematopoietic cells at specific locations on the platform. We demonstrate the capacity to identify discrete cells along the HSC differentiation hierarchy via multivariate analysis of Raman spectra. Notably, cell state identification is accurate for individual cells and independent of the biophysical properties of the functionalized polyacrylamide gels upon which these cells are cultured. We report partial least-squares discriminant analysis (PLS-DA) models of single cell Raman spectra enable identifying four dissimilar hematopoietic cell populations across the HSC lineage specification. Successful discrimination was obtained for a population enriched for long-term repopulating HSCs (LT-HSCs) versus their more differentiated progeny, including closely related short-term repopulating HSCs (ST-HSCs) and fully differentiated lymphoid (B cells) and myeloid (granulocytes) cells. The lineage-specific differentiation states of cells from these four subpopulations were accurately identified independent of the stiffness of the underlying biomaterial substrate, indicating subtle spectral variations that discriminated these populations were not masked by features from the culture substrate. This approach enables identifying the lineage-specific differentiation stages of hematopoietic cells on biomaterial substrates of differing composition and may facilitate correlating hematopoietic cell fate decisions with the extrinsic cues that

  15. Effect of dissolved oxygen on nitrogen and phosphorus removal and electricity production in microbial fuel cell.

    PubMed

    Tao, Qinqin; Luo, Jingjing; Zhou, Juan; Zhou, Shaoqi; Liu, Guangli; Zhang, Renduo

    2014-07-01

    Performance of a two-chamber microbial fuel cell (MFC) was evaluated with the influence of cathodic dissolved oxygen (DO). The maximum voltage, coulombic efficiency and maximum power density outputs of MFC decreased from 521 to 303 mV, 52.48% to 23.09% and 530 to 178 mW/m(2) with cathodic DO declining. Furthermore, a great deal of total phosphorus (TP) was removed owing to chemical precipitation (about 80%) and microbial absorption (around 4-17%). COD was first removed in anode chamber (>70%) then in cathode chamber (<5%). Most of nitrogen was removed when the cathodic DO was at low levels. Chemical precipitates formed in cathode chamber were verified as phosphate, carbonate and hydroxyl compound with the aid of scanning electron microscope capable of energy dispersive spectroscopy (SEM-EDS), X-ray diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR). PMID:24880930

  16. Molecular Targeting of Intracellular Compartments Specifically in Cancer Cells

    PubMed Central

    Pandya, Hetal; Gibo, Denise M.; Debinski, Waldemar

    2010-01-01

    We have implemented a strategy in which a genetically engineered, single-chain protein specifically recognizes cancer cells and is trafficked to a targeted subcellular compartment, such as the nucleus. The recombinant protein termed IL-13.E13K-D2-NLS has a triple functional property: (1) it binds a cancer-associated receptor, interleukin 13 receptor alpha 2 (IL-13Rα2), using modified IL-13 ligand, IL-13.E13K; (2) it exports its C-terminal portion out of the endosomal compartment using Pseudomonas aeruginosa exotoxin A (PE) translocation domain (D2); and (3) it travels to and accumulates in the nucleus guided by the nuclear localization signal (NLS). Here, we have demonstrated that this protein is transported into the brain tumor cells’ nucleus, using 3 different methods of protein conjugation to dyes for the purpose of direct visualization of the protein’s intracellular trafficking. IL-13.E13K-D2-NLS, and not the controls such as IL-13.E13K-D2, IL-13.E13K-NLS, or IL-13.E13K, accumulated in nuclei very efficiently, which increased with the time the cells were exposed to the protein. Also, IL-13.E13K-D2-NLS did not exhibit nuclear transport in cells with low expression levels of IL-13Rα2. Thus, it is possible to recognize cancer cells through their specific receptors and deliver a conjugated protein that travels specifically to the nucleus. Hence, our molecular targeting strategy succeeded in generating a single-chain proteinaceous agent capable of delivering drugs/labels needed to be localized to the cells’ nuclei or potentially any other subcellular compartment, for their optimal efficacy or ability to exert their specific action. PMID:20740056

  17. Statistical Physics of T-Cell Development and Pathogen Specificity

    NASA Astrophysics Data System (ADS)

    Košmrlj, Andrej; Kardar, Mehran; Chakraborty, Arup K.

    2013-04-01

    In addition to an innate immune system that battles pathogens in a nonspecific fashion, higher organisms, such as humans, possess an adaptive immune system to combat diverse (and evolving) microbial pathogens. Remarkably, the adaptive immune system mounts pathogen-specific responses, which can be recalled upon reinfection with the same pathogen. It is difficult to see how the adaptive immune system can be preprogrammed to respond specifically to a vast and unknown set of pathogens. Although major advances have been made in understanding pertinent molecular and cellular phenomena, the precise principles that govern many aspects of an immune response are largely unknown. We discuss complementary approaches from statistical mechanics and cell biology that can shed light on how key components of the adaptive immune system, T cells, develop to enable pathogen-specific responses against many diverse pathogens. The mechanistic understanding that emerges has implications for how host genetics may influence the development of T cells with differing responses to the human immunodeficiency virus (HIV) infection.

  18. Cell theory, specificity, and reproduction, 1837-1870.

    PubMed

    Müller-Wille, Staffan

    2010-09-01

    The cell is not only the structural, physiological, and developmental unit of life, but also the reproductive one. So far, however, this aspect of the cell has received little attention from historians and philosophers of biology. I will argue that cell theory had far-reaching consequences for how biologists conceptualized the reproductive relationships between germs and adult organisms. Cell theory, as formulated by Theodor Schwann in 1839, implied that this relationship was a specific and lawful one, that is, that germs of a certain kind, all else being equal, would produce adult organisms of the same kind, and vice versa. Questions of preformation and epigenesis took on a new meaning under this presupposition. The question then became one of whether cells could be considered as autonomous agents producing adult organisms of a given species, or whether they were the product of external, organizing forces and thus only a stage in the development of the whole organism. This question became an important issue for nineteenth-century biology. As I will demonstrate, it was the view of cells as autonomous agents which helped both Charles Darwin and Gregor Mendel to think of inheritance as a lawful process. PMID:20934643

  19. Cell Theory, Specificity, and Reproduction, 1837–1870

    PubMed Central

    Müller-Wille, Staffan

    2015-01-01

    The cell is not only the structural, physiological, and developmental, but also the reproductive unit of life. So far, however, this aspect of the cell has received little attention by historians and philosophers of biology. I will argue that cell theory had far-reaching consequences for how biologists conceptualized the reproductive relationships between germs and adult organisms. Cell theory, as formulated by Theodor Schwann in 1839, implied that this relationship was a specific and lawful one, i.e. that germs of a certain kind, all else being equal, would produce adult organisms of the same kind, and vice versa. Questions of preformation and epigenesis took on a new meaning under this presupposition. The question now was whether cells could be considered as independent agents producing adult organisms of a given species, or whether they were the product of external, organizing forces and thus a stage in the development of the whole organism only. The question was an important one for nineteenth-century biology. As I will demonstrate, it was the view of cells as independent agents which helped both Charles Darwin and Gregor Mendel to think of differential reproduction as a lawful process. PMID:20934643

  20. Tissue-specific cell wall hydration in sugarcane stalks.

    PubMed

    Maziero, Priscila; Jong, Jennifer; Mendes, Fernanda M; Gonçalves, Adilson R; Eder, Michaela; Driemeier, Carlos

    2013-06-19

    Plant cell walls contain water, especially under biological and wet processing conditions. The present work characterizes this water in tissues of sugarcane stalks. Environmental scanning electron microscopy shows tissue deformation upon drying. Dynamic vapor sorption determines the equilibrium and kinetics of moisture uptake. Thermoporometry by differential scanning calorimetry quantifies water in nanoscale pores. Results show that cell walls from top internodes of stalks are more deformable, slightly more sorptive to moisture, and substantially more porous. These differences of top internode are attributed to less lignified walls, which is confirmed by lower infrared spectral signal from aromatics. Furthermore, cell wall nanoscale porosity, an architectural and not directly compositional characteristic, is shown to be tissue-specific. Nanoscale porosities are ranked as follows: pith parenchyma > pith vascular bundles > rind. This ranking coincides with wall reactivity and digestibility in grasses, suggesting that nanoscale porosity is a major determinant of wall recalcitrance. PMID:23738592

  1. Specific inactivation of glucose metabolism from eucaryotic cells by pentalenolactone.

    PubMed

    Duszenko, M; Balla, H; Mecke, D

    1982-02-01

    Pentalenolactone, an antibiotic related to the class of the sesquiterpene-lactones and produced by the strain Streptomyces arenae Tü-469, inhibits specifically the glucose metabolism by inactivation of the enzyme glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate: NAD oxidoreductase (phosphorylating) ED 1.2.1.1.2). The sensitivity of several eucaryotic cell-systems for pentalenolactone was shown under in vivo conditions. The glycolytic as well as the gluconeogenetic pathway of mammalian cells can be completely inhibited with low concentrations of the antibiotic. In all cases, the minimum inhibitory concentration is dependent on cell density. The inhibitory effect in vivo and in vitro does not seem to be species-specific. In erythrocytes from rats, in Ehrlich-ascites tumor cells and in Plasmodium vinckei infected erythrocytes from mice glycolysis can be inhibited with concentrations of 18--90 micrometers pentalenolactone. In hepatocytes, glycolysis as well as gluconeogenesis in prevented by the same concentrations. In contrast to these results, in yeast the inhibition depends on growth conditions. The inhibition in glucose medium is cancelled by precultivation on acetate-containing medium. PMID:7034785

  2. Germ tube-specific antigens of Candida albicans cell walls

    SciTech Connect

    Sundstrom, P.R.

    1986-01-01

    Studies were performed to characterize the surface differences between blastospores and germ tubes of the pathogenic, dimorphic yeast, Candida albicans, and to identify components of yeast cells responsible for these differences. Investigation of surfaces differences of the two growth forms was facilitated by the production of rabbit antiserum prepared against Formalin-treated yeast possessing germ tubes. To prepare antiserum specific for germ tubes, this serum was adsorbed with stationary phase blastospores. Whereas the unadsorbed antiserum reacted with both blastospore and germ tube forms by immunofluorescence and Enzyme-Linked Immunosorbent Assay, the adsorbed antiserum did not react with blastospores but detected germ tube-specific antigens in hyphal forms. The differences between blastospores and germ tubes of Candida albicans, were further studied by comparing enzymatic digests of cell walls of both growth forms in radiolabeled organisms. Organisms were labeled either on the surface with /sup 125/I, or metabolically with (/sup 35/S) methionine or (/sup 3/H) mannose. Three-surface-located components (as shown by antibody adsorption and elution experiments) were precipitated from Zymolase digests. All three components were mannoproteins as shown by their ability to bind Concanavalin A, and to be labeled in protein labeling procedures, and two of these (200,000 and 155,000 molecular weight) were germ tube specific, as shown by their ability to be precipitated by germ tube-specific antiserum. Monoclonal antibodies were prepared to C. albicans, using blastospores bearing germ tubes as immunogen.

  3. Isotherm kinetics of Cr(III) removal by non-viable cells of Acinetobacter haemolyticus.

    PubMed

    Yahya, Siti Khairunnisa; Zakaria, Zainul Akmar; Samin, Jefri; Raj, A S Santhana; Ahmad, Wan Azlina

    2012-06-01

    The potential use of non-viable biomass of a Gram negative bacterium i.e. Acinetobacter haemolyticus to remove Cr(III) species from aqueous environment was investigated. Highest Cr(III) removal of 198.80 mg g(-1) was obtained at pH 5, biomass dosage of 15 mg cell dry weight, initial Cr(III) of 100 mg L(-1) and 30 min of contact time. The Langmuir and Freundlich models fit the experimental data (R(2)>0.95) while the kinetic data was best described using the pseudo second-order kinetic model (R(2)>0.99). Cr(III) was successfully recovered from the bacterial biomass using either 1M of CH(3)COOH, HNO(3) or H(2)SO(4) with 90% recovery. TEM and FTIR suggested the involvement of amine, carboxyl, hydroxyl and phosphate groups during the biosorption of Cr(III) onto the cell surface of A. haemolyticus. A. haemolyticus was also capable to remove 79.87 mg g(-1) Cr(III) (around 22.75%) from raw leather tanning wastewater. This study demonstrates the potential of using A. haemolyticus as biosorbent to remove Cr(III) from both synthetic and industrial wastewater. PMID:22398363

  4. Efficient salt removal in a continuously operated upflow microbial desalination cell with an air cathode.

    PubMed

    Jacobson, Kyle S; Drew, David M; He, Zhen

    2011-01-01

    Microbial desalination cells (MDCs) hold great promise for drinking water production because of potential energy savings during the desalination process. In this study, we developed a continuously operated MDC--upflow microbial desalination cell (UMDC) for the purpose of salt removal. During the 4-month operation, the UMDC constantly removed salts and generated bio-electricity. At a hydraulic retention time (HRT) of 4 days (salt solution) and current production of ∼62 mA, the UMDC was able to remove more than 99% of NaCl from the salt solution that had an initial salt concentration of 30 g total dissolved solids (TDS)/L. In addition, the TDS removal rate was 7.50 g TDSL(-1)d(-1) (salt solution volume) or 5.25 g TDSL(-1)d(-1) (wastewater volume), and the desalinated water met the drinking water standard, in terms of TDS concentration. A high charge transfer efficiency of 98.6% or 81% was achieved at HRT 1 or 4d. The UMDC produced a maximum power density of 30.8 W/m(3). The phenomena of bipolar electrodialysis and proton transport in the UMDC were discussed. These results demonstrated the potential of the UMDC as either a sole desalination process or a pre-desalination reactor for downstream desalination processes. PMID:20584603

  5. Removing heavy metals from synthetic effluents using "kamikaze" Saccharomyces cerevisiae cells.

    PubMed

    Ruta, Lavinia; Paraschivescu, Codruta; Matache, Mihaela; Avramescu, Sorin; Farcasanu, Ileana Cornelia

    2010-01-01

    One key step of the bioremediation processes designed to clean up heavy metal contaminated environments is growing resistant cells that accumulate the heavy metals to ensure better removal through a combination of biosorption and continuous metabolic uptake after physical adsorption. Saccharomyces cerevisiae cells can easily act as cation biosorbents, but isolation of mutants that are both hyperaccumulating and tolerant to heavy metals proved extremely difficult. Instead, mutants that are hypersensitive to heavy metals due to increased and continuous uptake from the environment were considered, aiming to use such mutants to reduce the heavy metal content of contaminated waters. In this study, the heavy metal hypersensitive yeast strain pmr1Delta was investigated for the ability to remove Mn2+, Cu2+, Co2+, or Cd2+ from synthetic effluents. Due to increased metal accumulation, the mutant strain was more efficient than the wild-type in removing Mn2+, Cu2+, or Co2+ from synthetic effluents containing 1-2 mM cations, with a selectivity and also in removing Mn2+ and Cd2+ from synthetic effluents containing 20-50 microM cations, with a selectivity Mn2+ > Cd2+. PMID:19795117

  6. A systematic mRNA control mechanism for germline stem cell homeostasis and cell fate specification

    PubMed Central

    Lee, Myon-Hee; Mamillapalli, Srivalli Swathi; Keiper, Brett D.; Cha, Dong Seok

    2016-01-01

    Germline stem cells (GSCs) are the best understood adult stem cell types in the nematode Caenorhabditis elegans, and have provided an important model system for studying stem cells and their cell fate in vivo, in mammals. In this review, we propose a mechanism that controls GSCs and their cell fate through selective activation, repression and mobilization of the specific mRNAs. This mechanism is acutely controlled by known signal transduction pathways (e.g., Notch signaling and Ras-ERK MAPK signaling pathways) and P granule (analogous to mammalian germ granule)-associated mRNA regulators (FBF-1, FBF-2, GLD-1, GLD-2, GLD-3, RNP-8 and IFE-1). Importantly, all regulators are highly conserved in many multi-cellular animals. Therefore, GSCs from a simple animal may provide broad insight into vertebrate stem cells (e.g., hematopoietic stem cells) and their cell fate specification. [BMB Reports 2016; 49(2): 93-98] PMID:26303971

  7. Removal of phenol in phenolic resin wastewater by a novel biomaterial: the Phanerochaete chrysosporium pellet containing chlamydospore-like cells.

    PubMed

    Hailei, Wang; Ping, Li; Yu, Qin; Hui, Yang

    2016-06-01

    A novel biomaterial, the Phanerochaete chrysosporium pellet (CP) composed of chlamydospore-like cells (CLCs), was prepared and its potential in treating phenolic resin wastewater was evaluated. CP possesses higher phenol removal ability in contrast with mycelial pellets of P. chrysosporium, and CLC can be seen as the naturally immobilized enzymes. At shake-flask level, the ideal pH value, temperature, and inoculation quantity of CP for treatment of 1430 mg/l phenol wastewater were pH 4-6, 30 °C, and 5.0 g/l, respectively, and the maximum specific removal rate, 41.1 mg phenol/g CP/h, was obtained in fixed bed reactor (FBR) when the flow rate of wastewater was 3.4 l/h. During the treatment, FBR harbored amounts of bacteria (135 genera) and eukaryotes, as analyzed by metagenomic sequencing. Bacterial pollution not only decreased reactor performance but also had a negative impact on reusability of CP. Hot water treatment (80-85 °C) is effective to inhibit bacterial pollution, and heat resistance of CLC makes the repeated regrowing of CP be feasible. This work presents an innovative and low-cost biomaterial for phenol removal and will be helpful for the practical application of P. chrysosporium in wastewater treatment. PMID:26860939

  8. Identification and Specification of the Mouse Skeletal Stem Cell

    PubMed Central

    Chan, Charles K.F.; Seo, Eun Young; Chen, James Y.; Lo, David; McArdle, Adrian; Sinha, Rahul; Tevlin, Ruth; Seita, Jun; Vincent-Tompkins, Justin; Wearda, Taylor; Lu, Wan-Jin; Senarath-Yapa, Kshemendra; Chung, Michael T.; Marecic, Owen; Tran, Misha; Yan, Kelley S.; Upton, Rosalynd; Walmsley, Graham G.; Lee, Andrew S.; Sahoo, Debashis; Kuo, Calvin; Weissman, Irving L.; Longaker, Michael T.

    2015-01-01

    Summary How are skeletal tissues derived from skeletal stem cells? Here, we map bone, cartilage and stromal development from a population of highly pure, post-natal skeletal stem cells (mouse Skeletal Stem Cell, mSSC) to its downstream progenitors of bone, cartilage and stromal tissue. We then investigated the transcriptome of the stem/progenitor cells for unique gene expression patterns that would indicate potential regulators of mSSC lineage commitment. We demonstrate that mSSC niche factors can be potent inducers of osteogenesis, and several specific combinations of recombinant mSSC niche factors can activate mSSC genetic programs in situ, even in non-skeletal tissues, resulting in de novo formation of cartilage or bone and bone marrow stroma. Inducing mSSC formation with soluble factors and subsequently regulating the mSSC niche to specify its differentiation towards bone, cartilage, or stromal cells could represent a paradigm shift in the therapeutic regeneration of skeletal tissues. PMID:25594184

  9. Memory T Cell-Specific Therapeutics in Organ Transplantation

    PubMed Central

    Page, Andrew J.; Ford, Mandy L.; Kirk, Allan D.

    2010-01-01

    Purpose of the Review This review details the role of memory T cells in physiologic and allospecific immunity, and summarizes the effects of immunosuppressive agents used to manipulate their function in the context of organ transplantation. Recent Findings Memory T cells are lymphocytes with characteristics that are thought to promote anamnestic immune responses. They have a unique capacity to generate rapid effector functions upon secondary exposure to a pathogen, and this is achieved through truncated requirements for antigen presentation, reduced activation thresholds, and enhanced trafficking and adhesion mechanisms. In general, these same mechanisms also appear to evoke improved efficiency in mediating allograft rejection. The phenotype of these cells has been increasingly well defined and associated with a characteristic pattern of susceptibility to immunosuppressive agents. This knowledge is now being exploited in the development of immune therapeutic regimens to selectively mollify T memory cell effects. Summary A specific targeting of memory T cells has potential to prevent allograft rejection in a more precise manner that current means of immunosuppression. However, these benefits will be balanced by the reciprocal risk of susceptibility to recurrent infection. PMID:19779342

  10. Site-specific Proteasome Phosphorylation Controls Cell Proliferation and Tumorigenesis

    PubMed Central

    Guo, Xing; Wang, Xiaorong; Wang, Zhiping; Banerjee, Sourav; Yang, Jing; Huang, Lan; Dixon, Jack E.

    2015-01-01

    Despite the fundamental importance of proteasomal degradation in cells, little is known about whether and how the 26S proteasome itself is regulated in coordination with various physiological processes. Here we show that the proteasome is dynamically phosphorylated during cell cycle at Thr25 of the 19S subunit Rpt3. CRISPR/Cas9-mediated genome editing, RNA interference and biochemical studies demonstrate that blocking Rpt3-Thr25 phosphorylation markedly impairs proteasome activity and impedes cell proliferation. Through a kinome-wide screen, we have identified dual-specificity tyrosine-regulated kinase 2 (DYRK2) as the primary kinase that phosphorylates Rpt3-Thr25, leading to enhanced substrate translocation and degradation. Importantly, loss of the single phosphorylation of Rpt3-Thr25 or knockout of DYRK2 significantly inhibits tumor formation by proteasome-addicted human breast cancer cells in mice. These findings define an important mechanism for proteasome regulation and demonstrate the biological significance of proteasome phosphorylation in regulating cell proliferation and tumorigenesis. PMID:26655835

  11. Cell Cycle Phase-Specific Drug Resistance as an Escape Mechanism of Melanoma Cells.

    PubMed

    Beaumont, Kimberley A; Hill, David S; Daignault, Sheena M; Lui, Goldie Y L; Sharp, Danae M; Gabrielli, Brian; Weninger, Wolfgang; Haass, Nikolas K

    2016-07-01

    The tumor microenvironment is characterized by cancer cell subpopulations with heterogeneous cell cycle profiles. For example, hypoxic tumor zones contain clusters of cancer cells that arrest in G1 phase. It is conceivable that neoplastic cells exhibit differential drug sensitivity based on their residence in specific cell cycle phases. In this study, we used two-dimensional and organotypic melanoma culture models in combination with fluorescent cell cycle indicators to investigate the effects of cell cycle phases on clinically used drugs. We demonstrate that G1-arrested melanoma cells, irrespective of the underlying cause mediating G1 arrest, are resistant to apoptosis induced by the proteasome inhibitor bortezomib or the alkylating agent temozolomide. In contrast, G1-arrested cells were more sensitive to mitogen-activated protein kinase pathway inhibitor-induced cell death. Of clinical relevance, pretreatment of melanoma cells with a mitogen-activated protein kinase pathway inhibitor, which induced G1 arrest, resulted in resistance to temozolomide or bortezomib. On the other hand, pretreatment with temozolomide, which induced G2 arrest, did not result in resistance to mitogen-activated protein kinase pathway inhibitors. In summary, we established a model to study the effects of the cell cycle on drug sensitivity. Cell cycle phase-specific drug resistance is an escape mechanism of melanoma cells that has implications on the choice and timing of drug combination therapies. PMID:26970356

  12. Site-specific DNA excision in transgenic rice with a cell-permeable cre recombinase.

    PubMed

    Cao, Ming-Xia; Huang, Jian-Qiu; Yao, Quan-Hong; Liu, Sheng-Jun; Wang, Cheng-Long; Wei, Zhi-Ming

    2006-01-01

    The removal of selected marker genes from transgenic plants is necessary to address biosafety concerns and to carry out further experiments with transgenic organisms. In the present study, the 12-amino-acid membrane translocation sequence (MTS) from the Kaposi fibroblast growth factor (FGF)-4 was used as a carrier to deliver enzymatically active Cre proteins into living plant cells, and to produce a site-specific DNA excision in transgenic rice plants. The process, which made cells permeable to Cre recombinase-mediated DNA recombination, circumvented the need to express Cre under spatiotemporal control and was proved to be a simple and efficient system to achieve marker-free transgenic plants. The ultimate aim of the present study is to develop commercial rice cultivars free from selected marker genes to hasten public acceptance of transgenic crops. PMID:16382182

  13. Gene-specific cell labeling using MiMIC transposons

    PubMed Central

    Gnerer, Joshua P.; Venken, Koen J. T.; Dierick, Herman A.

    2015-01-01

    Binary expression systems such as GAL4/UAS, LexA/LexAop and QF/QUAS have greatly enhanced the power of Drosophila as a model organism by allowing spatio-temporal manipulation of gene function as well as cell and neural circuit function. Tissue-specific expression of these heterologous transcription factors relies on random transposon integration near enhancers or promoters that drive the binary transcription factor embedded in the transposon. Alternatively, gene-specific promoter elements are directly fused to the binary factor within the transposon followed by random or site-specific integration. However, such insertions do not consistently recapitulate endogenous expression. We used Minos-Mediated Integration Cassette (MiMIC) transposons to convert host loci into reliable gene-specific binary effectors. MiMIC transposons allow recombinase-mediated cassette exchange to modify the transposon content. We developed novel exchange cassettes to convert coding intronic MiMIC insertions into gene-specific binary factor protein-traps. In addition, we expanded the set of binary factor exchange cassettes available for non-coding intronic MiMIC insertions. We show that binary factor conversions of different insertions in the same locus have indistinguishable expression patterns, suggesting that they reliably reflect endogenous gene expression. We show the efficacy and broad applicability of these new tools by dissecting the cellular expression patterns of the Drosophila serotonin receptor gene family. PMID:25712101

  14. Adoptive Immunotherapy using Regulatory T cells and Virus-specific T cells Derived from Cord Blood

    PubMed Central

    Hanley, Patrick J.; Bollard, Catherine M.; Brunstein, Claudio G

    2014-01-01

    Cord blood transplantation, an alternative to traditional stem cell transplants (bone marrow or peripheral blood stem cell transplantation), is an attractive option for patients lacking suitable stem cell transplant donors. Cord blood units have also proven to be a valuable donor source for the development of cellular therapeutics. Virus-specific T cells and regulatory T cells are two cord blood derived products that have shown promise in early phase clinical trials to prevent and/or treat viral infections and graft-versus-host disease (GvHD), respectively. Here we describe how current strategies utilizing cord blood-derived regulatory T cells and virus-specific T cells have been developed to improve outcomes for cord blood transplant recipients. PMID:25632003

  15. Isoform-specific targeting of ROCK proteins in immune cells

    PubMed Central

    Zanin-Zhorov, Alexandra; Flynn, Ryan; Waksal, Samuel D.; Blazar, Bruce R.

    2016-01-01

    ABSTRACT Rho-associated kinase 1 (ROCK1) and ROCK2 are activated by Rho GTPase and control cytoskeleton rearrangement through modulating the phosphorylation of their down-stream effector molecules. Although these 2 isoforms share more than 90% homology within their kinase domain the question of whether ROCK proteins function identically in different cell types is not clear. By using both pharmacological inhibition and genetic knockdown approaches recent studies suggest that the ROCK2 isoform plays an exclusive role in controlling of T-cell plasticity and macrophage polarization. Specifically, selective ROCK2 inhibition shifts the balance between pro-inflammatory and regulatory T-cell subsets via concurrent regulation of STAT3 and STAT5 phosphorylation, respectively. Furthermore, the administration of an orally available selective ROCK2 inhibitor effectively ameliorates clinical manifestations in experimental models of autoimmunity and chronic graft-vs.-host disease (cGVHD). Because ROCK2 inhibition results in the suppression of M2-type macrophages while favoring polarization of M1-type macrophages, ROCK2 inhibition can correct the macrophage imbalance seen during age-related macular degeneration (AMD). In summary, the exclusive role of ROCK2 in immune system modulation argues for the development and testing of isoform-specific ROCK2 inhibitors for the treatment of inflammatory disorders. PMID:27254302

  16. Patient-specific blood rheology in sickle-cell anaemia.

    PubMed

    Li, Xuejin; Du, E; Lei, Huan; Tang, Yu-Hang; Dao, Ming; Suresh, Subra; Karniadakis, George Em

    2016-02-01

    Sickle-cell anaemia (SCA) is an inherited blood disorder exhibiting heterogeneous cell morphology and abnormal rheology, especially under hypoxic conditions. By using a multiscale red blood cell (RBC) model with parameters derived from patient-specific data, we present a mesoscopic computational study of the haemodynamic and rheological characteristics of blood from SCA patients with hydroxyurea (HU) treatment (on-HU) and those without HU treatment (off-HU). We determine the shear viscosity of blood in health as well as in different states of disease. Our results suggest that treatment with HU improves or worsens the rheological characteristics of blood in SCA depending on the degree of hypoxia. However, on-HU groups always have higher levels of haematocrit-to-viscosity ratio (HVR) than off-HU groups, indicating that HU can indeed improve the oxygen transport potential of blood. Our patient-specific computational simulations suggest that the HVR level, rather than the shear viscosity of sickle RBC suspensions, may be a more reliable indicator in assessing the response to HU treatment. PMID:26855752

  17. Specific cell surface labeling of GPCRs using split GFP.

    PubMed

    Jiang, Wen-Xue; Dong, Xu; Jiang, Jing; Yang, Yu-Hong; Yang, Ju; Lu, Yun-Bi; Fang, San-Hua; Wei, Er-Qing; Tang, Chun; Zhang, Wei-Ping

    2016-01-01

    Specific cell surface labeling is essential for visualizing the internalization processes of G-protein coupled receptors (GPCRs) and for gaining mechanistic insight of GPCR functions. Here we present a rapid, specific, and versatile labeling scheme for GPCRs at living-cell membrane with the use of a split green fluorescent protein (GFP). Demonstrated with two GPCRs, GPR17 and CysLT2R, we show that two β-stands (β-stands 10 and 11) derived from a superfolder GFP (sfGFP) can be engineered to one of the three extracellular loop of a GPCR. The complementary fragment of sfGFP has nine β-strands (β-stands 1-9) that carries the mature fluorophore, and can be proteolytically derived from the full-length sfGFP. Separately the GFP fragments are non-fluorescent, but become fluorescent upon assembly, thus allowing specific labeling of the target proteins. The two GFP fragments rapidly assemble and the resulting complex is extremely tight under non-denaturing conditions, which allows real-time and quantitative assessment of the internalized GPCRs. We envision that this labeling scheme will be of great use for labeling other membrane proteins in various biological and pharmacological applications. PMID:26857153

  18. Removal of hexavalent chromium ions by Yarrowia lipolytica cells modified with phyto-inspired Fe0/Fe3O4 nanoparticles

    NASA Astrophysics Data System (ADS)

    Rao, Ashit; Bankar, Ashok; Kumar, Ameeta Ravi; Gosavi, Suresh; Zinjarde, Smita

    2013-03-01

    The removal of hexavalent chromium [Cr (VI)], an important ground water pollutant by phyto-inspired Fe0/Fe3O4 nanocomposite-modified cells of Yarrowia lipolytica (NCIM 3589 and NCIM 3590), was investigated. Electron microscopy and magnetometer studies indicated an effective modification of yeast cell surfaces by the nanocomposites. The effect of pH, temperature, agitation speed, contact time and initial metal ion concentration on the removal of Cr (VI) was determined. The specific uptake values at pH 2.0 were 186.32 ± 3.17 and 137.31 ± 4.53 mg g- 1 for NCIM 3589 and NCIM 3590, respectively, when 1000 mg L- 1 of metal ion concentrations were used. The equilibrium data fitted to Scatchard, Langmuir and linearized Freundlich models suggesting that adsorption played a role in the removal of Cr (VI) ions. The surface modified yeast cells displayed higher values of Langmuir and Scatchard coefficients than the unmodified cells indicating that the former were more efficient in Cr (VI) removal. The enhanced detoxification of Cr (VI) ions by this composite material could be attributed to the reductive power of the Fe0/Fe3O4 nanocomposites as well the yeast cell surface functional groups.

  19. Effect of Removal of Spermatogonial Stem Cells (SSCs) from In Vitro Culture on Gene Expression of Niche Factors in Bovine

    PubMed Central

    Akbarinejad, Vahid; Tajik, Parviz; Movahedin, Mansoureh; Youssefi, Reza

    2016-01-01

    Background: Niche cells, regulating Spermatogonial Stem Cells (SSCs) fate are believed to have a reciprocal communication with SSCs. The present study was conducted to evaluate the effect of SSC elimination on the gene expression of Glial cell line-Derived Neurotrophic Factor (GDNF), Fibroblast Growth Factor 2 (FGF2) and Kit Ligand (KITLG), which are the main growth factors regulating SSCs development and secreted by niche cells, primarily Sertoli cells. Methods: Following isolation, bovine testicular cells were cultured for 12 days on extracellular matrix-coated plates. In the germ cell-removed group, the SSCs were removed from the in vitro culture using differential plating; however, in the control group, no intervention in the culture was performed. Colony formation of SSCs was evaluated using an inverted microscope. The gene expression of growth factors and spermatogonia markers were assessed using quantitative real time PCR. Results: SSCs colonies were developed in the control group but they were rarely observed in the germ cell-removed group; moreover, the expression of spermatogonia markers was detected in the control group while it was not observed in the germ cell-removed group, substantiating the success of SSCs removal. The expression of Gdnf and Fgf2 was greater in the germ cell-removed than control group (p<0.05), whereas the expression of Kitlg was lower in the germ cell-removed than control group (p< 0.05). Conclusion: In conclusion, the results revealed that niche cells respond to SSCs removal by upregulation of GDNF and FGF2, and downregulation of KITLG in order to stimulate self-renewal and arrest differentiation. PMID:27563426

  20. Linking the T cell receptor to the single cell transcriptome in antigen-specific human T cells.

    PubMed

    Eltahla, Auda A; Rizzetto, Simone; Pirozyan, Mehdi R; Betz-Stablein, Brigid D; Venturi, Vanessa; Kedzierska, Katherine; Lloyd, Andrew R; Bull, Rowena A; Luciani, Fabio

    2016-07-01

    Heterogeneity of T cells is a hallmark of a successful adaptive immune response, harnessing the vast diversity of antigen-specific T cells into a coordinated evolution of effector and memory outcomes. The T cell receptor (TCR) repertoire is highly diverse to account for the highly heterogeneous antigenic world. During the response to a virus multiple individual clones of antigen specific CD8+ (Ag-specific) T cells can be identified against a single epitope and multiple epitopes are recognised. Advances in single-cell technologies have provided the potential to study Ag-specific T cell heterogeneity at both surface phenotype and transcriptome levels, thereby allowing investigation of the diversity within the same apparent sub-population. We propose a new method (VDJPuzzle) to reconstruct the native TCRαβ from single cell RNA-seq data of Ag-specific T cells and then to link these with the gene expression profile of individual cells. We applied this method using rare Ag-specific T cells isolated from peripheral blood of a subject who cleared hepatitis C virus infection. We successfully reconstructed productive TCRαβ in 56 of a total of 63 cells (89%), with double α and double β in 18, and 7% respectively, and double TCRαβ in 2 cells. The method was validated via standard single cell PCR sequencing of the TCR. We demonstrate that single-cell transcriptome analysis can successfully distinguish Ag-specific T cell populations sorted directly from resting memory cells in peripheral blood and sorted after ex vivo stimulation. This approach allows a detailed analysis of the TCR diversity and its relationship with the transcriptional profile of different clones. PMID:26860370

  1. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1998-08-04

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4 C storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4 C for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials. 8 figs.

  2. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOEpatents

    Bitensky, Mark W.; Yoshida, Tatsuro

    1998-01-01

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4.degree. C. storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4.degree. C. for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials.

  3. Effect of damage removal etch (DRE) on plasma textured, multi-crystalline solar cells

    NASA Astrophysics Data System (ADS)

    Majumdar, S.; Pathak, M.; Chahar, N.; Sharan, A.; Saxena, A. K.; Bhattacharya, S.

    2014-10-01

    In the present work, a self-masked, dry, plasma texturing process for multi crystalline silicon (mc-Si) wafers has been developed that results in a higher cell performance than that with un-textured wafers. Plasma textured samples prepared have low levels (∼4%) of reflectance. Plasma damage of textured wafers has been eliminated by a damage removal etch (DRE). The improvement in efficiency of mc-Si solar cells up to 15.1% has been attributed to complete suppression of reflectivity (4-5%) in a broad spectral range (350-800 nm) leading to black silicon surface. Also, DRE on plasma textured wafers has been found to result in reduced surface damage compared to cells without DRE leading to higher cell efficiencies.

  4. Tract specific analysis in patients with sickle cell disease

    NASA Astrophysics Data System (ADS)

    Chai, Yaqiong; Coloigner, Julie; Qu, Xiaoping; Choi, Soyoung; Bush, Adam; Borzage, Matt; Vu, Chau; Lepore, Natasha; Wood, John

    2015-12-01

    Sickle cell disease (SCD) is a hereditary blood disorder in which the oxygen-carrying hemoglobin molecule in red blood cells is abnormal. It affects numerous people in the world and leads to a shorter life span, pain, anemia, serious infections and neurocognitive decline. Tract-Specific Analysis (TSA) is a statistical method to evaluate white matter alterations due to neurocognitive diseases, using diffusion tensor magnetic resonance images. Here, for the first time, TSA is used to compare 11 major brain white matter (WM) tracts between SCD patients and age-matched healthy subjects. Alterations are found in the corpus callosum (CC), the cortico-spinal tract (CST), inferior fronto-occipital fasciculus (IFO), inferior longitudinal fasciculus (ILF), superior longitudinal fasciculus (SLF), and uncinated fasciculus (UNC). Based on previous studies on the neurocognitive functions of these tracts, the significant areas found in this paper might be related to several cognitive impairments and depression, both of which are observed in SCD patients.

  5. WT1-specific T cell receptor gene therapy: improving TCR function in transduced T cells.

    PubMed

    Stauss, Hans J; Thomas, Sharyn; Cesco-Gaspere, Michela; Hart, Daniel P; Xue, Shao-An; Holler, Angelika; King, Judy; Wright, Graham; Perro, Mario; Pospori, Constantina; Morris, Emma

    2008-01-01

    Adoptive transfer of antigen-specific T lymphocytes is an attractive form of immunotherapy for haematological malignancies and cancer. The difficulty of isolating antigen-specific T lymphocytes for individual patients limits the more widespread use of adoptive T cell therapy. The demonstration that cloned T cell receptor (TCR) genes can be used to produce T lymphocyte populations of desired specificity offers new opportunities for antigen-specific T cell therapy. The first trial in humans demonstrated that TCR gene-modified T cells persisted for an extended time period and reduced tumor burden in some patients. The WT1 protein is an attractive target for immunotherapy of leukemia and solid cancer since elevated expression has been demonstrated in AML, CML, MDS and in breast, colon and ovarian cancer. In the past, we have isolated high avidity CTL specific for a WT1-derived peptide presented by HLA-A2 and cloned the TCR alpha and beta genes of a WT1-specific CTL line. The genes were inserted into retroviral vectors for transduction of human peripheral blood T lymphocytes of leukemia patients and normal donors. The treatment of leukemia-bearing NOD/SCID mice with T cells transduced with the WT1-specific TCR eliminated leukemia cells in the bone marrow of most mice, while treatment with T cells transduced with a TCR of irrelevant specificity did not diminish the leukemia burden. In order to improve the safety and efficacy of TCR gene therapy, we have developed lentiviral TCR gene transfer. In addition, we employed strategies to enhance TCR expression while avoiding TCR mis-pairing. It may be possible to generate dominant TCR constructs that can suppress the expression of the endogenous TCR on the surface of transduced T cells. The development of new TCR gene constructs holds great promise for the safe and effective delivery of TCR gene therapy for the treatment of malignancies. PMID:17855129

  6. Analyzing center specific outcomes in hematopoietic cell transplantation.

    PubMed

    Logan, Brent R; Nelson, Gene O; Klein, John P

    2008-12-01

    Reporting transplant center-specific survival rates after hematopoietic cell transplantation is required in the United States. We describe a method to report 1-year survival outcomes by center, as well as to quantify center performance relative to the transplant center network average, which can be reliably used with censored data and for small center sizes. Each center's observed 1-year survival outcome is compared to a predicted survival outcome adjusted for patient characteristics using a pseudovalue regression technique. A 95% prediction interval for 1-year survival assuming no center effect is computed for each center by bootstrapping the scaled residuals from the regression model, and the observed 1-year survival is compared to this prediction interval to determine center performance. We illustrate the technique using a recent center specific analysis performed by the Center for International Blood and Marrow Transplant Research, and study the performance of this method using simulation. PMID:18836830

  7. Role of specific endocytic pathways in electrotransfection of cells.

    PubMed

    Chang, Chun-Chi; Wu, Mina; Yuan, Fan

    2014-01-01

    Electrotransfection is a technique utilized for gene delivery in both preclinical and clinical studies. However, its mechanisms are not fully understood. The goal of this study was to investigate specific pathways of endocytosis involved in electrotransfection. In the study, three different human cell lines (HEK293, HCT116, and HT29) were either treated with ice cold medium postelectrotransfection or endocytic inhibitors prior to electrotransfection. The inhibitors were pharmacological agents (chlorpromazine, genistein, and amiloride) or different small interfering RNA (siRNA) molecules that could knockdown expression of clathrin heavy chain (CLTC), caveolin-1, and Rab34, respectively. The reduction in gene expressions was confirmed with western blot analysis at 48-72h post-siRNA treatment. It was observed that treatments with either ice cold medium, chlorpromazine, or genistein resulted in significant reductions in electrotransfection efficiency (eTE) in all three cell lines, compared to the matched controls, but amiloride treatment had insignificant effects on eTE. For cells treated with siRNA, only CLTC knockdown resulted in eTE reduction for all three cell lines. Together, these data demonstrated that the clathrin-mediated endocytosis played an important role in electrotransfection. PMID:26052524

  8. Natural killer cells facilitate PRAME-specific T-cell reactivity against neuroblastoma

    PubMed Central

    Spel, Lotte; Boelens, Jaap-Jan; van der Steen, Dirk M.; Blokland, Nina J.G.; van Noesel, Max M.; Molenaar, Jan J.; Heemskerk, Mirjam H.M.

    2015-01-01

    Neuroblastoma is the most common solid tumor in children with an estimated 5-year progression free survival of 20–40% in stage 4 disease. Neuroblastoma actively avoids recognition by natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). Although immunotherapy has gained traction for neuroblastoma treatment, these immune escape mechanisms restrain clinical results. Therefore, we aimed to improve neuroblastoma immunogenicity to further the development of antigen-specific immunotherapy against neuroblastoma. We found that neuroblastoma cells significantly increase surface expression of MHC I upon exposure to active NK cells which thereby readily sensitize neuroblastoma cells for recognition by CTLs. We show that oncoprotein PRAME serves as an immunodominant antigen for neuroblastoma as NK-modulated neuroblastoma cells are recognized by PRAMESLLQHLIGL/A2-specific CTL clones. Furthermore, NK cells induce MHC I upregulation in neuroblastoma through contact-dependent secretion of IFNγ. Our results demonstrate remarkable plasticity in the peptide/MHC I surface expression of neuroblastoma cells, which is reversed when neuroblastoma cells experience innate immune attack by sensitized NK cells. These findings support the exploration of NK cells as adjuvant therapy to enforce neuroblastoma-specific CTL responses. PMID:26452036

  9. Electrosorption driven by microbial fuel cells to remove phenol without external power supply.

    PubMed

    Yang, Jie; Zhou, Minghua; Zhao, Yingying; Zhang, Chao; Hu, Youshuang

    2013-12-01

    This work studied the operating parameters (pH, electrolyte concentration, initial phenol concentration, MFCs connection numbers and mode), adsorption isotherms and kinetics of a novel electrosorption driven by microbial fuel cells (MFC-Sorption) to remove phenol without external electric grid energy supply. It proved that high electrolyte concentration and low solution pH promoted the performance of phenol removal. 3 MFCs connections in series achieved a adsorption capacity of 1.76 mmol/g, which was much higher than that in parallel connection (1.46 mmol/g). Well fitted with Langmuir isotherm, the maximum adsorption capacity by MFC-Sorption and electrosorption was observed 48% and 65% higher than that by conventional adsorption. The phenol removal by MFC-Sorption was supposed to be more suitable for a pseudo-second-order kinetics, and with the increase of initial phenol concentration from 20 mg/L to 300 mg/L, the initial adsorption rate increased 26.99-fold. It concluded that the MFC-Sorption system could cost-effectively remove pollutant of phenol. PMID:24177161

  10. Polyfunctional T cells accumulate in large human cytomegalovirus-specific T cell responses.

    PubMed

    Lachmann, Raskit; Bajwa, Martha; Vita, Serena; Smith, Helen; Cheek, Elizabeth; Akbar, Arne; Kern, Florian

    2012-01-01

    Large cytomegalovirus (CMV)-specific CD8 T-cell responses are observed in both young and, somewhat more often, old people. Frequent CMV reactivation is thought to exhaust these cells and render them dysfunctional so that larger numbers of them are needed to control CMV. Expansions of CMV-specific CD4 T cells are also seen but are less well studied. In this study, we examined the T-cell response to the dominant CMV pp65 and IE-1 antigens in healthy CMV-infected people across a wide age range (20 to 84 years) by using multicolor flow cytometry. CMV-specific T cells were characterized by the activation markers CD40 ligand (CD40L), interleukin-2 (IL-2), tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) and the memory markers CD27 and CD45RA. The proportions of effector memory T cells increased in large responses, as did the proportions of polyfunctional CD8 (IFN-γ(+) IL-2(+/-) TNF-α(+)) and CD4 (CD40L(+/-) IFN-γ(+) IL-2(+) TNF-α(+)) T-cell subsets, while the proportion of naïve T cells decreased. The bigger the CD4 or CD8 T-cell response to pp65, the larger was the proportion of T cells with an advanced memory phenotype in the entire (including non-CMV-specific) T-cell compartment. In addition, the number of activation markers per cell correlated with the degree of T-cell receptor downregulation, suggesting increased antigen sensitivity in polyfunctional cells. In summary, our findings show that polyfunctional CMV-specific T cells were not superseded by dysfunctional cells, even in very large responses. At the same time, however, the memory subset composition of the entire T-cell compartment correlated with the size of the T-cell response to CMV pp65, confirming a strong effect of CMV infection on the immune systems of some, but not all, infected people. PMID:22072753

  11. Removal of myeloid cytokines from the cellular environment enhances T-cell development in vitro.

    PubMed

    Smeets, Monique F M A; Mackenzie-Kludas, Charley; Mohtashami, Mahmood; Zhang, Hui-Hua; Zúñiga-Pflücker, Juan Carlos; Izon, David J

    2013-10-01

    The majority of T-cell development occurs in the thymus. Thymic epithelial cells are specialized cells that express NOTCH ligands and secrete specific cytokines required for normal T-cell lymphopoiesis. It has been demonstrated that OP9 cells derived from macrophage colony-stimulating factor (M-CSF)-deficient mice can support T-cell development when transduced with a NOTCH ligand, Delta-like 1 (Dll1). In this report, we have tested CSF-deficient mouse fibroblasts transduced with Dll1 for their ability to support T-cell differentiation. The data provided here demonstrate that CSF-deficient fibroblasts expressing DLL1 can support T-cell development. Indeed, co-cultures with these fibroblasts produced more T-cell progenitors compared with OP9-DL1 cultures. Addition of myeloid cytokines to OP9-DL1 co-cultures significantly inhibited T-cell development while CSF-deficient DLL1(+) fibroblasts retained partial T-cell differentiation. Taken together, these data imply that their lack of myeloid cytokines allows DLL1(+) fibroblasts to more efficiently generate T-cells. Development of this fibroblast system suggests that there is potential for generating human T-cell precursors via co-culture with human fibroblasts expressing DLL1 or DLL4. These T-cell precursors could be used for treating immunodeficient patients. PMID:23988615

  12. Immuno-Navigator, a batch-corrected coexpression database, reveals cell type-specific gene networks in the immune system

    PubMed Central

    Vandenbon, Alexis; Dinh, Viet H.; Mikami, Norihisa; Kitagawa, Yohko; Teraguchi, Shunsuke; Ohkura, Naganari; Sakaguchi, Shimon

    2016-01-01

    High-throughput gene expression data are one of the primary resources for exploring complex intracellular dynamics in modern biology. The integration of large amounts of public data may allow us to examine general dynamical relationships between regulators and target genes. However, obstacles for such analyses are study-specific biases or batch effects in the original data. Here we present Immuno-Navigator, a batch-corrected gene expression and coexpression database for 24 cell types of the mouse immune system. We systematically removed batch effects from the underlying gene expression data and showed that this removal considerably improved the consistency between inferred correlations and prior knowledge. The data revealed widespread cell type-specific correlation of expression. Integrated analysis tools allow users to use this correlation of expression for the generation of hypotheses about biological networks and candidate regulators in specific cell types. We show several applications of Immuno-Navigator as examples. In one application we successfully predicted known regulators of importance in naturally occurring Treg cells from their expression correlation with a set of Treg-specific genes. For one high-scoring gene, integrin β8 (Itgb8), we confirmed an association between Itgb8 expression in forkhead box P3 (Foxp3)-positive T cells and Treg-specific epigenetic remodeling. Our results also suggest that the regulation of Treg-specific genes within Treg cells is relatively independent of Foxp3 expression, supporting recent results pointing to a Foxp3-independent component in the development of Treg cells. PMID:27078110

  13. Selective Removal of DNA from Dead Cells of Mixed Bacterial Communities by Use of Ethidium Monoazide

    PubMed Central

    Nocker, Andreas; Camper, Anne K.

    2006-01-01

    The distinction between viable and dead bacterial cells poses a major challenge in microbial diagnostics. Due to the persistence of DNA in the environment after cells have lost viability, DNA-based quantification methods overestimate the number of viable cells in mixed populations or even lead to false-positive results in the absence of viable cells. On the other hand, RNA-based diagnostic methods, which circumvent this problem, are technically demanding and suffer from some drawbacks. A promising and easy-to-use alternative utilizing the DNA-intercalating dye ethidium monoazide bromide (EMA) was published recently. This chemical is known to penetrate only into “dead” cells with compromised cell membrane integrity. Subsequent photoinduced cross-linking was reported to inhibit PCR amplification of DNA from dead cells. We provide evidence here that in addition to inhibition of amplification, most of the DNA from dead cells is actually lost during the DNA extraction procedure, probably together with cell debris which goes into the pellet fraction. Exposure of bacteria to increasing stress and higher proportions of dead cells in defined populations led to increasing loss of genomic DNA. Experiments were performed using Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium as model pathogens and using real-time PCR for their quantification. Results showed that EMA treatment of mixed populations of these two species provides a valuable tool for selective removal of DNA of nonviable cells by using conventional extraction protocols. Furthermore, we provide evidence that prior to denaturing gradient gel electrophoresis, EMA treatment of a mature mixed-population drinking-water biofilm containing a substantial proportion of dead cells can result in community fingerprints dramatically different from those for an untreated biofilm. The interpretation of such fingerprints can have important implications in the field of microbial ecology. PMID:16517648

  14. Selective removal of DNA from dead cells of mixed bacterial communities by use of ethidium monoazide.

    PubMed

    Nocker, Andreas; Camper, Anne K

    2006-03-01

    The distinction between viable and dead bacterial cells poses a major challenge in microbial diagnostics. Due to the persistence of DNA in the environment after cells have lost viability, DNA-based quantification methods overestimate the number of viable cells in mixed populations or even lead to false-positive results in the absence of viable cells. On the other hand, RNA-based diagnostic methods, which circumvent this problem, are technically demanding and suffer from some drawbacks. A promising and easy-to-use alternative utilizing the DNA-intercalating dye ethidium monoazide bromide (EMA) was published recently. This chemical is known to penetrate only into "dead" cells with compromised cell membrane integrity. Subsequent photoinduced cross-linking was reported to inhibit PCR amplification of DNA from dead cells. We provide evidence here that in addition to inhibition of amplification, most of the DNA from dead cells is actually lost during the DNA extraction procedure, probably together with cell debris which goes into the pellet fraction. Exposure of bacteria to increasing stress and higher proportions of dead cells in defined populations led to increasing loss of genomic DNA. Experiments were performed using Escherichia coli O157:H7 and Salmonella enterica serovar Typhimurium as model pathogens and using real-time PCR for their quantification. Results showed that EMA treatment of mixed populations of these two species provides a valuable tool for selective removal of DNA of nonviable cells by using conventional extraction protocols. Furthermore, we provide evidence that prior to denaturing gradient gel electrophoresis, EMA treatment of a mature mixed-population drinking-water biofilm containing a substantial proportion of dead cells can result in community fingerprints dramatically different from those for an untreated biofilm. The interpretation of such fingerprints can have important implications in the field of microbial ecology. PMID:16517648

  15. Osmotically induced removal of water from fungal cells as determined by a spin probe technique.

    PubMed

    Miller, R W

    1978-11-01

    Effects of physical environment on plasma membrane semipermeability and osmotic induction of changes in aqueous cytoplasmic volume were studied in vegetative and spore cells of a plant pathogenic fungus, Fusarium sulphureum. A direct method, employing a spin probe molecule that partitioned between intracellular aqueous and hydrophobic phases, allowed measurement of reversible water movement out of macroconidial cells and chlamydospores exposed to solutions of high osmolarity. Equilibrium distribution of the spin probe between intracellular aqueous and lipid phases was more rapid than movement of water in and out of the cells. The extent of water removal was exponentially dependent on osmotic strength. Some cells became irreversibly permeable to divalent cations on treatment with sodium chloride above 1.5 osmolar but addition of sucrose to the suspension medium at equivalent osmolar concentrations caused water removal without adversely affecting the viability. Sucrose also protected the plasma membrane against damage during freeze-drying. Induction of plasma membrane damage by osmotic shock or freeze-drying permitted rapid permeation of nickel ions. Neither slow equilibration of intracellular components with divalent paramagnetic cations nor partial permeability of damaged plasma membranes to these ions was observed. PMID:16660597

  16. Sickle cell hospital unit: a disease-specific model.

    PubMed

    Adams-Graves, Patricia; Ostric, Elizabeth J; Martin, Mary; Richardson, Pat; Lewis, James B

    2008-01-01

    American urban hospitals often serve large populations of sickle cell disease (SCD) patients. Those hospitals that choose to implement an adult SCD-specific inpatient unit have the opportunity to acquire multiple operational benefits. Such units may ultimately reduce patient morbidity and mortality; improve timely access to quality medical care in a cost-effective manner; reduce overcrowding in the emergency department; and increase patient, family, physician, and payer satisfaction. SCD is a serious, painful, genetic blood disorder that affects a growing population of adults in the United States. A single mistake in the gene that codes for hemoglobin causes crescent-shaped red blood cells that are sticky, are stiff, and have a short life span. These cells cause blockages, tremendous pain brought on by lack of oxygen in the muscles, organ damage, stroke, and problems with infections. The cells' short life span often results in anemia. The unpredictable pain event-sickle cell disease with crisis-is the most common reason for presentation to the emergency department and for hospital admission. For many SCD patients, the emergency department process and the general, overly conservative approach to pain relief lead to a delay in treatment and prolong needless suffering. Regional Medical Center at Memphis (Tennessee) established an SCD unit and developed an inpatient care delivery model that decreases the burden of caring for SCD patients on its busy emergency department, improves SCD patients' satisfaction and access to timely quality care, and reduces the needless pain and suffering of SCD patients. This SCD model may be replicated in large urban hospitals with a daily SCD patient census of five or more. PMID:18856136

  17. A recombinant antibody with the antigen-specific, major histocompatibility complex-restricted specificity of T cells.

    PubMed Central

    Andersen, P S; Stryhn, A; Hansen, B E; Fugger, L; Engberg, J; Buus, S

    1996-01-01

    Specific recognition of peptide/major histocompatibility complex (MHC) molecule complexes by the T-cell receptor is a key reaction in the specific immune response. Antibodies against peptide/MHC complexes would therefore be valuable tools in studying MHC function and T-cell recognition and might lead to novel approaches in immunotherapy. However, it has proven difficult to generate antibodies with the specificity of T cells by conventional hybridoma techniques. Here we report that the phage display technology is a feasible alternative to generate antibodies recognizing specific, predetermined peptide/MHC complexes. Images Fig. 2 PMID:8700842

  18. Optimization of enhanced bioelectrical reactor with electricity from microbial fuel cells for groundwater nitrate removal.

    PubMed

    Liu, Ye; Zhang, Baogang; Tian, Caixing; Feng, Chuanping; Wang, Zhijun; Cheng, Ming; Hu, Weiwu

    2016-04-01

    Factors influencing the performance of a continual-flow bioelectrical reactor (BER) intensified by microbial fuel cells for groundwater nitrate removal, including nitrate load, carbon source and hydraulic retention time (HRT), were investigated and optimized by response surface methodology (RSM). With the target of maximum nitrate removal and minimum intermediates accumulation, nitrate load (for nitrogen) of 60.70 mg/L, chemical oxygen demand (COD) of 849.55 mg/L and HRT of 3.92 h for the BER were performed. COD was the dominant factor influencing performance of the system. Experimental results indicated the undistorted simulation and reliable optimized values. These demonstrate that RSM is an effective method to evaluate and optimize the nitrate-reducing performance of the present system and can guide mathematical models development to further promote its practical applications. PMID:26402418

  19. Cost-effective copper removal by electrosorption powered by microbial fuel cells.

    PubMed

    Yang, Jie; Zhou, Minghua; Hu, Youshuang; Yang, Weilu

    2016-03-01

    This work studied a cost-effective electrosorption that driven by microbial fuel cells (MFC-sorption) to remove Cu(2+) from wastewater without an external energy supply. The impact factors, adsorption isotherms and kinetics of the novel process were investigated. It indicated that a low electrolyte concentration and a high solution pH could enhance the Cu(2+) removal efficiency, while the adsorption capacity increased with the increase of numbers of MFCs in series and the initial Cu(2+) concentration. The adsorption isotherms study indicated that the monolayer adsorption in MFC-sorption was dominant. The kinetics study suggested the increase of initial Cu(2+) concentration could enhance the initial adsorption rate. The electrode characterizations verified the existence of Cu2O and Cu on the electrode surface of active carbon fibers (ACFs), suggesting that MFC-sorption was not only an adsorption process, but also a redox reaction process. PMID:26747441

  20. Periodic Shorting of SOM Cell to Remove Soluble Magnesium in Molten Flux and Improve Faradaic Efficiency

    NASA Astrophysics Data System (ADS)

    Guan, Xiaofei; Su, Shizhao; Pal, Uday B.; Powell, Adam C.

    2014-12-01

    Solid oxide membrane (SOM) electrolysis has been used for magnesium production directly from magnesium oxide. Magnesium dissolution in molten flux electrolyte is of particular concern in SOM electrolysis, because it imparts electronic conductivity to the flux and thereby decreases the faradaic current efficiency. In this work, a new approach for removing soluble magnesium in the flux is explored. Periodic shorting is performed between the anode and the cathode of SOM electrolysis cell. During shorting, soluble magnesium in the flux is oxidized to magnesium oxide. This significantly reduces the electronic current in the flux and therefore keeps the faradaic current efficiency high during SOM electrolysis. Electronic transference numbers in the flux are measured to assess the soluble magnesium concentration. Potentiodynamic scan results also confirm the feasibility of shorting the electrodes to remove soluble magnesium.

  1. Enhancement of bacterial denitrification for nitrate removal in groundwater with electrical stimulation from microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Zhang, Baogang; Liu, Ye; Tong, Shuang; Zheng, Maosheng; Zhao, Yinxin; Tian, Caixing; Liu, Hengyuan; Feng, Chuanping

    2014-12-01

    Electricity generated from the microbial fuel cell (MFC) is applied to the bioelectrical reactor (BER) directly as electrical stimulation means for enhancement of bacterial denitrification to remove nitrate effectively from groundwater. With maximum power density of 502.5 mW m-2 and voltage outputs ranging from 500 mV to 700 mV, the nitrate removal is accelerated, with less intermediates accumulation, compared with control sets without electrical stimulation. Denitrification bacteria proliferations and activities are promoted as its number and Adenosine-5'-triphosphate (ATP) concentration increased one order of magnitude (3.5 × 107 in per milliliter biofilm solution) and about 1.5 folds, respectively. Effects of electricity from MFCs on enhancement of bacterial behaviors are demonstrated for the first time. These results indicate that MFCs can be applied in the in-situ bioremediation of nitrate polluted groundwater for efficiency improvement.

  2. Cell-specific modulation of surfactant proteins by ambroxol treatment.

    PubMed

    Seifart, Carola; Clostermann, Ursula; Seifart, Ulf; Müller, Bernd; Vogelmeier, Claus; von Wichert, Peter; Fehrenbach, Heinz

    2005-02-15

    Ambroxol [trans-4-(2-amino-3,5-dibromobenzylamino)-cyclohexanole hydrochloride], a mucolytic agent, was postulated to provide surfactant stimulatory properties and was previously used to prevent surfactant deficiency. Currently, the underlying mechanisms are not exactly clear. Because surfactant homeostasis is regulated by surfactant-specific proteins (SP), we analyzed protein amount and mRNA expression in whole lung tissue, isolated type II pneumocytes and bronchoalveolar lavage of Sprague-Dawley rats treated with ambroxol i.p. (75 mg/kg body weight, twice a day [every 12 h]). The methods used included competitive polymerase chain reaction (RT-PCR), Northern blotting, Western immunoblotting, and immunohistochemistry. In isolated type II pneumocytes of ambroxol-treated animals, SP-C protein and mRNA content were increased, whereas SP-A, -B and -D protein, mRNA, and immunoreactivity remained unaffected. However, ambroxol treatment resulted in a significant increase of SP-B and in a decrease of SP-D in whole lung tissue with enhanced immunostaining for SP-B in Clara Cells. SP-A and SP-D were significantly decreased in BAL fluid of ambroxol-treated animals. The data suggest that surfactant protein expression is modulated in a cell-specific manner by ambroxol, as type II pneumocytes exhibited an increase in SP-C, whereas Clara cells exhibited an increase in the immunoreactivity for SP-B accounting for the increased SP-B content of whole lung tissue. The results indicate that ambroxol may exert its positive effects, observed in the treatment of diseases related to surfactant deficiency, via modulation of surfactant protein expression. PMID:15694461

  3. Cell-specific modulation of surfactant proteins by ambroxol treatment

    SciTech Connect

    Seifart, Carola . E-mail: zwiebel@mailer.uni-marburg.de; Clostermann, Ursula; Seifart, Ulf

    2005-02-15

    Ambroxol [trans-4-(2-amino-3,5-dibromobenzylamino)-cyclohexanole hydrochloride], a mucolytic agent, was postulated to provide surfactant stimulatory properties and was previously used to prevent surfactant deficiency. Currently, the underlying mechanisms are not exactly clear. Because surfactant homeostasis is regulated by surfactant-specific proteins (SP), we analyzed protein amount and mRNA expression in whole lung tissue, isolated type II pneumocytes and bronchoalveolar lavage of Sprague-Dawley rats treated with ambroxol i.p. (75 mg/kg body weight, twice a day [every 12 h]). The methods used included competitive polymerase chain reaction (RT-PCR), Northern blotting, Western immunoblotting, and immunohistochemistry. In isolated type II pneumocytes of ambroxol-treated animals, SP-C protein and mRNA content were increased, whereas SP-A, -B and -D protein, mRNA, and immunoreactivity remained unaffected. However, ambroxol treatment resulted in a significant increase of SP-B and in a decrease of SP-D in whole lung tissue with enhanced immunostaining for SP-B in Clara Cells. SP-A and SP-D were significantly decreased in BAL fluid of ambroxol-treated animals. The data suggest that surfactant protein expression is modulated in a cell-specific manner by ambroxol, as type II pneumocytes exhibited an increase in SP-C, whereas Clara cells exhibited an increase in the immunoreactivity for SP-B accounting for the increased SP-B content of whole lung tissue. The results indicate that ambroxol may exert its positive effects, observed in the treatment of diseases related to surfactant deficiency, via modulation of surfactant protein expression.

  4. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and burrows pond rearing system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We compared the hydrodynamics of replicate experimental mixed cell and replicate standard Burrows pond rearing systems at the Dworshak National Fish Hatchery, ID, in an effort to identify methods for improved solids removal. We measured and compared the hydraulic residence time, particle removal eff...

  5. Comparison of hydraulics and particle removal efficiencies in a mixed cell raceway and Burrows pond rearing system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We compared the hydrodynamics of replicate experimental mixed cell and replicate standard Burrows pond rearing systems at the Dworshak National Fish Hatchery, ID, in an effort to identify methods for improved solids removal. We measured and compared the hydraulic residence time, particle removal eff...

  6. Oncolytic viruses & their specific targeting to tumour cells

    PubMed Central

    Singh, Prafull K.; Doley, Juwar; Kumar, G. Ravi; Sahoo, A.P.; Tiwari, Ashok K.

    2012-01-01

    Cancer is one of the major causes of death worldwide. In spite of achieving significant successes in medical sciences in the past few decades, the number of deaths due to cancer remains unchecked. The conventional chemotherapy and radiotherapy have limited therapeutic index and a plethora of treatment related side effects. This situation has provided an impetus for search of novel therapeutic strategies that can selectively destroy the tumour cells, leaving the normal cells unharmed. Viral oncotherapy is such a promising treatment modality that offers unique opportunity for tumour targeting. Numerous viruses with inherent anti-cancer activity have been identified and are in different phases of clinical trials. In the era of modern biotechnology and with better understanding of cancer biology and virology, it has become feasible to engineer the oncolytic viruses (OVs) to increase their tumour selectivity and enhance their oncolytic activity. In this review, the mechanisms by which oncolytic viruses kill the tumour cells have been discussed as also the development made in virotherapy for cancer treatment with emphasis on their tumour specific targeting. PMID:23168697

  7. Cell-type-specific gene delivery into neuronal cells in vitro and in vivo.

    PubMed

    Parveen, Zahida; Mukhtar, Muhammad; Rafi, Mohammed; Wenger, David A; Siddiqui, Khwaja M; Siler, Catherine A; Dietzschold, Bernhard; Pomerantz, Roger J; Schnell, Matthias J; Dornburg, Ralph

    2003-09-15

    The avian retroviruses reticuloendotheliosis virus strain A (REV-A) and spleen necrosis virus (SNV) are not naturally infectious in human cells. However, REV-A-derived viral vectors efficiently infect human cells when they are pseudotyped with envelope proteins displaying targeting ligands specific for human cell-surface receptors. Here we report that vectors containing the gag region of REV-A and pol of SNV can be pseudotyped with the envelope protein of vesicular stomatitis virus (VSV) and the glycoproteins of different rabies virus (RV) strains. Vectors pseudotyped with the envelope protein of the highly neurotropic RV strain CVS-N2c facilitated cell type-specific gene delivery into mouse and human neurons, but did not infect other human cell types. Moreover, when such vector particles were injected into the brain of newborn mice, only neuronal cells were infected in vivo. Cell-type-specific gene delivery into neurons may present quite specific gene therapy approaches for many degenerative diseases of the brain. PMID:14517061

  8. Comparison of Habitat-Specific Nutrient Removal and Release in Pacific NW Salt Marshes at Multiple Spatial Scales - CERF

    EPA Science Inventory

    Wetlands can be sources, sinks and transformers of nutrients, although it is their role in nutrient removal that is valued as a water purification ecosystem service. In order to quantify that service for any wetland, it is important to understand the drivers of nutrient removal w...

  9. Comparison of Habitat-Specific Nutrient Removal and Release in Pacific NW Salt Marshes at Multiple Spatial Scales

    EPA Science Inventory

    Wetlands can be sources, sinks and transformers of nutrients, although it is their role in nutrient removal that is valued as a water purification ecosystem service. In order to quantify that service for any wetland, it is important to understand the drivers of nutrient removal w...

  10. Post-growth process for flexible CdS/CdTe thin film solar cells with high specific power.

    PubMed

    Cho, Eunwoo; Kang, Yoonmook; Kim, Donghwan; Kim, Jihyun

    2016-05-16

    We demonstrated a flexible CdS/CdTe thin film solar cell with high specific power of approximately 254 W/kg. A flexible and ultra-light weight CdS/CdTe cell treated with pre-NP etch process exhibited high conversion efficiency of 13.56% in superstrate configuration. Morphological, structural and optical changes of CdS/CdTe thin films were characterized when pre-NP etch step was incorporated to the conventional post-deposition process. Improvement of photovoltaic parameters can be attributed to the removal of the oxide and the formation of Te-rich layer, which benefit the activation process. Pre-NP etched cell maintained their flexibility and performance under the repeated tensile strain of 0.13%. Our method can pave a way for manufacturing flexible CdS/CdTe thin film solar cells with high specific power for mobile and aerospace applications. PMID:27409952

  11. A Cytokine-Independent Approach To Identify Antigen-Specific Human Germinal Center T Follicular Helper Cells and Rare Antigen-Specific CD4+ T Cells in Blood.

    PubMed

    Dan, Jennifer M; Lindestam Arlehamn, Cecilia S; Weiskopf, Daniela; da Silva Antunes, Ricardo; Havenar-Daughton, Colin; Reiss, Samantha M; Brigger, Matthew; Bothwell, Marcella; Sette, Alessandro; Crotty, Shane

    2016-08-01

    Detection of Ag-specific CD4(+) T cells is central to the study of many human infectious diseases, vaccines, and autoimmune diseases. However, such cells are generally rare and heterogeneous in their cytokine profiles. Identification of Ag-specific germinal center (GC) T follicular helper (Tfh) cells by cytokine production has been particularly problematic. The function of a GC Tfh cell is to selectively help adjacent GC B cells via cognate interaction; thus, GC Tfh cells may be stingy cytokine producers, fundamentally different from Th1 or Th17 cells in the quantities of cytokines produced. Conventional identification of Ag-specific cells by intracellular cytokine staining relies on the ability of the CD4(+) T cell to generate substantial amounts of cytokine. To address this problem, we have developed a cytokine-independent activation-induced marker (AIM) methodology to identify Ag-specific GC Tfh cells in human lymphoid tissue. Whereas Group A Streptococcus-specific GC Tfh cells produced minimal detectable cytokines by intracellular cytokine staining, the AIM method identified 85-fold more Ag-specific GC Tfh cells. Intriguingly, these GC Tfh cells consistently expressed programmed death ligand 1 upon activation. AIM also detected non-Tfh cells in lymphoid tissue. As such, we applied AIM for identification of rare Ag-specific CD4(+) T cells in human peripheral blood. Dengue, tuberculosis, and pertussis vaccine-specific CD4(+) T cells were readily detectable by AIM. In summary, cytokine assays missed 98% of Ag-specific human GC Tfh cells, reflecting the biology of these cells, which could instead be sensitively identified by coexpression of TCR-dependent activation markers. PMID:27342848

  12. Cell-of-Origin-Specific 3D Genome Structure Acquired during Somatic Cell Reprogramming

    PubMed Central

    Krijger, Peter Hugo Lodewijk; Di Stefano, Bruno; de Wit, Elzo; Limone, Francesco; van Oevelen, Chris; de Laat, Wouter; Graf, Thomas

    2016-01-01

    Summary Forced expression of reprogramming factors can convert somatic cells into induced pluripotent stem cells (iPSCs). Here we studied genome topology dynamics during reprogramming of different somatic cell types with highly distinct genome conformations. We find large-scale topologically associated domain (TAD) repositioning and alterations of tissue-restricted genomic neighborhoods and chromatin loops, effectively erasing the somatic-cell-specific genome structures while establishing an embryonic stem-cell-like 3D genome. Yet, early passage iPSCs carry topological hallmarks that enable recognition of their cell of origin. These hallmarks are not remnants of somatic chromosome topologies. Instead, the distinguishing topological features are acquired during reprogramming, as we also find for cell-of-origin-dependent gene expression patterns. PMID:26971819

  13. Tissue-Specific Stem Cells in the Myometrium and Tumor-Initiating Cells in Leiomyoma1

    PubMed Central

    Ono, Masanori; Bulun, Serdar E.; Maruyama, Tetsuo

    2014-01-01

    ABSTRACT Tissue-specific (or somatic) stem cells constitute a subset of cells residing in normal adult tissues. By undergoing asymmetric division, they retain their ability to self-renew while producing daughter cells that go on to differentiate and play a role in tissue regeneration and repair. The human uterus consists primarily of endometrium and myometrium (the smooth muscle layer) that rapidly enlarges through its tremendous regenerative and remodeling capacity to accommodate the developing fetus. Such uterine enlargement and remodeling can take place repeatedly and cyclically over the course of a woman's reproductive life. These unique properties of the uterus suggest the existence of endometrial and myometrial stem cell systems. In addition, like somatic cells, tumor stem cells or tumor-initiating cells, a subset of cells within a tumor, retain the ability to reconstitute tumors. Uterine smooth muscle cells are thought to be the origin of leiomyomas that are the most common type of gynecologic tumor. Recent work has identified, isolated, and characterized putative stem/progenitor cells in the myometrium and in leiomyomas. Here, we review current studies of myometrial and leiomyoma stem/progenitor cells and provide a new paradigm for understanding myometrial physiology and pathology and how these cells might contribute to uterine remodeling during pregnancy and the formation of leiomyomas. The role of the WNT/CTNNB1 pathway in the pathogenesis of leiomyoma is also discussed. PMID:25376230

  14. Chemically Modified Plastic Tube for High Volume Removal and Collection of Circulating Tumor Cells

    PubMed Central

    Gaitas, Angelo; Kim, Gwangseong

    2015-01-01

    In this preliminary effort, we use a commercially available and chemically modified tube to selectively capture circulating tumor cells (CTCs) from the blood stream by immobilizing human anti-EpCAM antibodies on the tube's interior surface. We describe the requisite and critical steps required to modify a tube into a cancer cell-capturing device. Using these simple modifications, we were able to capture or entrap about 85% of cancer cells from suspension and 44% of cancer cells from spiked whole blood. We also found that the percentage of cells captured was dependent on the tube's length and also the number of cancer cells present. It is our strong belief that with the utilization of appropriate tube lengths and procedures, we can ensure capture and removal of nearly the entire CTC population in whole blood. Importantly after a patient’s entire blood volume has circulated through the tube, the tube can then be trypsinized to release the captured live CTCs for further analysis and testing. PMID:26176235

  15. Chemically Modified Plastic Tube for High Volume Removal and Collection of Circulating Tumor Cells.

    PubMed

    Gaitas, Angelo; Kim, Gwangseong

    2015-01-01

    In this preliminary effort, we use a commercially available and chemically modified tube to selectively capture circulating tumor cells (CTCs) from the blood stream by immobilizing human anti-EpCAM antibodies on the tube's interior surface. We describe the requisite and critical steps required to modify a tube into a cancer cell-capturing device. Using these simple modifications, we were able to capture or entrap about 85% of cancer cells from suspension and 44% of cancer cells from spiked whole blood. We also found that the percentage of cells captured was dependent on the tube's length and also the number of cancer cells present. It is our strong belief that with the utilization of appropriate tube lengths and procedures, we can ensure capture and removal of nearly the entire CTC population in whole blood. Importantly after a patient's entire blood volume has circulated through the tube, the tube can then be trypsinized to release the captured live CTCs for further analysis and testing. PMID:26176235

  16. Renal Cell Carcinoma Presenting as Right Atrial Tumor with Successful Removal Using Cardiopulmonary Bypass

    PubMed Central

    Paul, Joy G.; Rhodes, Donald B.; Skow, James R.

    1975-01-01

    A 58-year-old male presented with signs and symptoms of right sided heart failure. Diagnostic evaluation revealed a right renal cell carcinoma with extension into the vena cava and right atrium. Surgical management included radical right nephrectomy with retroperitoneal lymph node dissection, inferior vena caval resection, and removal of the intra-atrial tumor thrombus using a cardiopulmonary bypass. Two years after surgery the patient is alive and well with no evidence of recurrent disease. ImagesFig. 1.Fig. 2a.Fig. 2b.Fig. 3. PMID:1130867

  17. The specific reactive surface area of granular zero-valent iron in metal contaminant removal: Column experiments and modelling.

    PubMed

    Statham, Tom M; Mason, Lachlan R; Mumford, Kathryn A; Stevens, Geoffrey W

    2015-06-15

    A series of dynamic-flow kinetic experiments were conducted to assess the removal rates of aqueous Cu(2+) and Zn(2+) ions by zero-valent iron (ZVI), a promising material for inclusion in cold-climate remediation applications. The influence of experimental parameters on contaminant removal rates, including aqueous flow rate, operating temperature, and the concentrations of ZVI, salt and dissolved oxygen, was investigated. A mass transport model has been developed that accounts (i) aqueous-phase dispersion processes, (ii) film diffusion of contaminant ions to the reactive ZVI surface and (iii) the reactive removal mechanism itself. Regression to the experimental data indicated that when oxygen is present in the solution feed Cu(2+) and Zn(2+) removal processes were limited by film diffusion. In de-aerated solutions film diffusion still controls Cu(2+) removal but a first-order surface reaction provides a better model for Zn(2+) kinetics. Using air as the equilibrium feed gas, the reactive proportion of the total surface area for contaminant removal was calculated to be 97% and 64% of the active spherically-assumed geometric area associated with ZVI media for Cu(2+) and Zn(2+), respectively. Relative to a gas absorption area, determined in previous studies, the reactive proportion is less than 0.41% of the unreacted ZVI total surface area. These findings suggest that only part of the iron oxyhydroxide surface is reacting during ZVI based metal contaminant removal. PMID:25839833

  18. Increasing functional avidity of TCR-redirected T cells by removing defined N-glycosylation sites in the TCR constant domain

    PubMed Central

    Hauptrock, Beate; Malina, Victoria; Antunes, Edite; Voss, Ralf-Holger; Wolfl, Matthias; Strong, Roland; Theobald, Matthias; Greenberg, Philip D.

    2009-01-01

    Adoptive transfer of T lymphocytes transduced with a T cell receptor (TCR) to impart tumor reactivity has been reported as a potential strategy to redirect immune responses to target cancer cells (Schumacher, T.N. 2002. Nat. Rev. Immunol. 2:512–519). However, the affinity of most TCRs specific for shared tumor antigens that can be isolated is usually low. Thus, strategies to increase the affinity of TCRs or the functional avidity of TCR-transduced T cells might be therapeutically beneficial. Because glycosylation affects the flexibility, movement, and interactions of surface molecules, we tested if selectively removing conserved N-glycoslyation sites in the constant regions of TCR α or β chains could increase the functional avidity of T cells transduced with such modified TCRs. We observed enhanced functional avidity and improved recognition of tumor cells by T cells harboring TCR chains with reduced N-glycosylation (ΔTCR) as compared with T cells with wild-type (WT) TCR chains. T cells transduced with WT or ΔTCR chains bound tetramer equivalently at 4°C, but tetramer binding was enhanced at 37°C, predominantly as a result of reduced tetramer dissociation. This suggested a temperature-dependent mechanism such as TCR movement in the cell surface or structural changes of the TCR allowing improved multimerization. This strategy was effective with mouse and human TCRs specific for different antigens and, thus, should be readily translated to TCRs with any specificity. PMID:19171765

  19. Reinnervation of Hair Cells by Auditory Neurons after Selective Removal of Spiral Ganglion Neurons

    PubMed Central

    Martinez-Monedero, Rodrigo; Corrales, C. Eduardo; Cuajungco, Math P.; Heller, Stefan; Edge, Albert S.B.

    2007-01-01

    Hearing loss can be caused by primary degeneration of spiral ganglion neurons or by secondary degeneration of these neurons after hair cell loss. The replacement of auditory neurons would be an important step in any attempt to restore auditory function in patients with damaged inner ear neurons or hair cells. Application of β-bungarotoxin, a toxin derived from snake venom, to an explant of the cochlea eradicates spiral ganglion neurons while sparing the other cochlear cell types. The toxin was found to bind to the neurons and to cause apoptotic cell death without affecting hair cells or other inner ear cell types as indicated by TUNEL staining, and, thus, the toxin provides a highly specific means of deafferentation of hair cells. We therefore used the denervated organ of Corti for the study of neuronal regeneration and synaptogenesis with hair cells and found that spiral ganglion neurons obtained from the cochlea of an untreated newborn mouse reinnervated hair cells in the toxin-treated organ of Corti and expressed synaptic vesicle markers at points of contact with hair cells. These findings suggest that it may be possible to replace degenerated neurons by grafting new cells into the organ of Corti. PMID:16408287

  20. A novel and highly specific phage endolysin cell wall binding domain for detection of Bacillus cereus.

    PubMed

    Kong, Minsuk; Sim, Jieun; Kang, Taejoon; Nguyen, Hoang Hiep; Park, Hyun Kyu; Chung, Bong Hyun; Ryu, Sangryeol

    2015-09-01

    Rapid, specific and sensitive detection of pathogenic bacteria is crucial for public health and safety. Bacillus cereus is harmful as it causes foodborne illness and a number of systemic and local infections. We report a novel phage endolysin cell wall-binding domain (CBD) for B. cereus and the development of a highly specific and sensitive surface plasmon resonance (SPR)-based B. cereus detection method using the CBD. The newly discovered CBD from endolysin of PBC1, a B. cereus-specific bacteriophage, provides high specificity and binding capacity to B. cereus. By using the CBD-modified SPR chips, B. cereus can be detected at the range of 10(5)-10(8) CFU/ml. More importantly, the detection limit can be improved to 10(2) CFU/ml by using a subtractive inhibition assay based on the pre-incubation of B. cereus and CBDs, removal of CBD-bound B. cereus, and SPR detection of the unbound CBDs. The present study suggests that the small and genetically engineered CBDs can be promising biological probes for B. cereus. We anticipate that the CBD-based SPR-sensing methods will be useful for the sensitive, selective, and rapid detection of B. cereus. PMID:26043681

  1. Nitrogen removal from wastewater through microbial electrolysis cells and cation exchange membrane

    PubMed Central

    2014-01-01

    Vulnerability of water resources to nutrients led to progressively stricter standards for wastewater effluents. Modification of the conventional procedures to meet the new standards is inevitable. New technologies should give a priority to nitrogen removal. In this paper, ammonium chloride and urine as nitrogen sources were used to investigate the capacity of a microbial electrolysis cell (MEC) configured by cation exchange membrane (CEM) for electrochemical removal of nitrogen over open-and closed-circuit potentials (OCP and CCP) during biodegradation of organic matter. Results obtained from this study indicated that CEM was permeable to both organic and ammonium nitrogen over OCP. Power substantially mediated ammonium migration from anodic wastewater to the cathode, as well. With a urine rich wastewater in the anode, the maximum rate of ammonium intake into the cathode varied from 34.2 to 40.6 mg/L.h over CCP compared to 10.5-14.9 mg/L.h over OCP. Ammonium separation over CCP was directly related to current. For 1.46-2.12 mmol electron produced, 20.5-29.7 mg-N ammonium was removed. Current also increased cathodic pH up to 12, a desirable pH for changing ammonium ion to ammonia gas. Results emphasized the potential for MEC in control of ammonium through ammonium separation and ammonia volatilization provided that membrane characteristic is considered in their development. PMID:24533446

  2. A microbial fuel cell driven capacitive deionization technology for removal of low level dissolved ions.

    PubMed

    Feng, Cuijie; Hou, Chia-Hung; Chen, Shaohua; Yu, Chang-Ping

    2013-04-01

    The microbial fuel cell (MFC) is an emerging technology, which uses exoelectrogenic microorganisms to oxidize organic matter in the wastewater to produce electricity. However, the low energy output limits its application in practice. Capacitive deionization (CDI), an electrochemically controlled method for deionization by the adsorption of ions in the electrical double layer region at an electrode-solution interface, requires a low external power supply. Therefore, in this study, we investigated the MFC driven CDI (MFC-CDI) technology to integrate deionization with wastewater treatment and electricity production. Taking advantage of the low potential requirement of CDI, voltage generated from a continuous flow MFC could be used to drive the CDI to achieve removal of the electrolyte to a stable status. The results indicated that among the three connection types of MFCs including single-, series-, and parallel-configuration, the parallel connection of two MFCs resulted in the highest potential (0.63V) applied to CDI and the conductivity removal of NaCl solution was more than 60%. The electrosorption capacities under different electrolyte concentrations of 50, 100 and 150 mg L(-1) were 150, 346 and 295 μg g(-1), respectively. These results suggest that the new MFC-CDI technology, which utilizes energy recovery from the wastewater, has great potential to be an energy saving technology to remove low level dissolved ions from aqueous solutions for the water and wastewater treatment processes. PMID:23375820

  3. Simultaneous Removal of Phenol and Dissolved Solids from Wastewater Using Multichambered Microbial Desalination Cell.

    PubMed

    Pradhan, Harapriya; Jain, Sumat Chand; Ghangrekar, Makarand M

    2015-12-01

    Microbial desalination cell (MDC) has great potential toward direct electricity generation from wastewater and concurrent desalination through potential difference developed due to microbial activity. Degradation of phenol by isolate Pseudomonas aeruginosa in anodic chamber and simultaneous desalination of water in middle desalination chamber of multichamber MDC is demonstrated in this study. Performance of the MDCs with different anodic inoculum conditions, namely pure culture of P. aeruginosa (MDC-1), 50 % v/v mixture of P. aeruginosa and anaerobic mixed consortia (MDC-2) and anaerobic mixed consortia (MDC-3), was evaluated to compare the phenol degradation in anodic chamber, bioelectricity generation, and simultaneous total dissolved solids (TDS) removal from saline water in desalination chamber. Synergistic effect between P. aeruginosa and mixed anaerobic consortia as inoculum was evident in MDC-2 demonstrating phenol degradation of 90 %, TDS removal of 75 % in 72 h of reaction time along with higher power generation of 27.5 mW/m(2) as compared to MDC-1 (95 %, 64 %, 12.8 mW/m(2), respectively) and MDC-3 (58 %, 52 %, 4.8 mW/m(2), respectively). The results illustrate that the multichamber MDC-2 is effective for simultaneous removal of phenol and dissolved solids contained in industrial wastewaters. PMID:26373945

  4. Simultaneous phenol removal, nitrification and denitrification using microbial fuel cell technology.

    PubMed

    Feng, Chunhua; Huang, Liqiao; Yu, Hui; Yi, Xiaoyun; Wei, Chaohai

    2015-06-01

    Here we show that concomitant removal of phenol and nitrogen can be accomplished in a single dual-chamber microbial fuel cell (MFC) reactor, in which the two chambers are separated with an anion-exchange membrane. A series of experiments were performed with ammonium (230 NH4(+)-N mg L(-1)) and phenol (with concentrations varying from 0 to 1400 mg L(-1)) fed to the aerobic cathode chamber of the MFC. Experimental results demonstrated that no apparent inhibitory effect of phenol on the nitrifying reaction was noted even at the phenol concentration up to 600 mg L(-1). For all the experiments, simultaneous nitrification and denitrification was achieved in the MFC. In comparison to the traditional aerobic bioreactor (ABR) and the same MFC run under the open-circuit condition, the MFC reactor allowed less inhibition of nitrification to phenol exposure and higher rate of nitrogen removal. The data of bacterial analysis revealed that electrochemically active bacteria and denitrifiers in the anaerobic chamber play a significant role in electricity generation and anaerobic denitrification, respectively, while phenol-degrading bacteria, nitrifiers, and denitrifiers in the aerobic cathode chamber are responsible for phenol oxidation, aerobic nitrification and aerobic denitrification, respectively. These results imply that the MFC holds potential for simultaneous removal of phenolic compounds and nitrogen contained in some particular industrial wastewaters. PMID:25813490

  5. Human T-Cell Clones from Autoimmune Thyroid Glands: Specific Recognition of Autologous Thyroid Cells

    NASA Astrophysics Data System (ADS)

    Londei, Marco; Bottazzo, G. Franco; Feldmann, Marc

    1985-04-01

    The thyroid glands of patients with autoimmune diseases such as Graves' disease and certain forms of goiter contain infiltrating activated T lymphocytes and, unlike cells of normal glands, the epithelial follicular cells strongly express histocompatability antigens of the HLA-DR type. In a study of such autoimmune disorders, the infiltrating T cells from the thyroid glands of two patients with Graves' disease were cloned in mitogen-free interleukin-2 (T-cell growth factor). The clones were expanded and their specificity was tested. Three types of clones were found. One group, of T4 phenotype, specifically recognized autologous thyroid cells. Another, also of T4 phenotype, recognized autologous thyroid or blood cells and thus responded positively in the autologous mixed lymphocyte reaction. Other clones derived from cells that were activated in vivo were of no known specificity. These clones provide a model of a human autoimmune disease and their analysis should clarify mechanisms of pathogenesis and provide clues to abrogating these undesirable immune responses.

  6. Quantum dot-labeled aptamer nanoprobes specifically targeting glioma cells

    NASA Astrophysics Data System (ADS)

    Chen, Xue-Chai; Deng, Yu-Lin; Lin, Yi; Pang, Dai-Wen; Qing, Hong; Qu, Feng; Xie, Hai-Yan

    2008-06-01

    Two new techniques, aptamer-based specific recognition and quantum dot (QD)-based fluorescence labeling, are becoming increasingly important in biosensing. In this study, these two techniques have been coupled together to construct a new kind of fluorescent QD-labeled aptamer (QD-Apt) nanoprobe by conjugating GBI-10 aptamer to the QD surface. GBI-10 is a single-stranded DNA (ssDNA) aptamer for tenascin-C, which distributes on the surface of glioma cells as a dominant extracellular matrix protein. The QD-Apt nanoprobe can recognize the tenascin-C on the human glioma cell surface, which will be helpful for the development of new convenient and sensitive in vitro diagnostic assays for glioma. The QD-Apt nanoprobe has particular features such as strong fluorescence, stability, monodispersity and uniformity. In addition, this probe preparation method is universal, so it is expected to provide a new type of stable nanoprobe for high-throughput and fast biosensing detection and bioimaging. New methods for real-time and dynamic tracking and imaging can be accordingly developed.

  7. T cells in the control of organ-specific autoimmunity

    PubMed Central

    Bluestone, Jeffrey A.; Bour-Jordan, Hélène; Cheng, Mickie; Anderson, Mark

    2015-01-01

    Immune tolerance is critical to the avoidance of unwarranted immune responses against self antigens. Multiple, non-redundant checkpoints are in place to prevent such potentially deleterious autoimmune responses while preserving immunity integral to the fight against foreign pathogens. Nevertheless, a large and growing segment of the population is developing autoimmune diseases. Deciphering cellular and molecular pathways of immune tolerance is an important goal, with the expectation that understanding these pathways will lead to new clinical advances in the treatment of these devastating diseases. The vast majority of autoimmune diseases develop as a consequence of complex mechanisms that depend on genetic, epigenetic, molecular, cellular, and environmental elements and result in alterations in many different checkpoints of tolerance and ultimately in the breakdown of immune tolerance. The manifestations of this breakdown are harmful inflammatory responses in peripheral tissues driven by innate immunity and self antigen–specific pathogenic T and B cells. T cells play a central role in the regulation and initiation of these responses. In this Review we summarize our current understanding of the mechanisms involved in these fundamental checkpoints, the pathways that are defective in autoimmune diseases, and the therapeutic strategies being developed with the goal of restoring immune tolerance. PMID:25985270

  8. Specific Visualization of Tumor Cells Using Upconversion Nanophosphors

    PubMed Central

    Grebenik, E. A.; Generalova, A. N.; Nechaev, A. V.; Khaydukov, E.V.; Mironova, K. E.; Stremovskiy, O. A.; Lebedenko, E.N.; Zvyagin, A. V.; Deyev, S. M.

    2014-01-01

    The development of targeted constructs on the basis of photoluminescent nanoparticles with a high photo- and chemical stability and absorption/emission spectra in the “transparency window” of biological tissues is an important focus area of present-day medical diagnostics. In this work, a targeted two-component construct on the basis of upconversion nanophosphors (UCNPs) and anti-tumor 4D5 scFv was developed for selective labeling of tumor cells overexpressing the HER2 tumor marker characteristic of a number of human malignant tumors. A high affinity barnase : barstar (Bn : Bs) protein pair, which exhibits high stability in a wide range of pH and temperatures, was exploited as a molecular adapter providing self-assembly of the two-component construct. High selectivity for the binding of the two-component 4D5 scFv-Bn : UCNP-Bs construct to human breast adenocarcinoma SK-BR-3 cells overexpressing HER2 was demonstrated. This approach provides an opportunity to produce similar constructs for the visualization of different specific markers in pathogenic tissues, including malignant tumors. PMID:25558394

  9. Cell Type-Specific Modulation of Respiratory Chain Supercomplex Organization.

    PubMed

    Sun, Dayan; Li, Bin; Qiu, Ruyi; Fang, Hezhi; Lyu, Jianxin

    2016-01-01

    Respiratory chain complexes are organized into large supercomplexes among which supercomplex In + IIIn + IVn is the only one that can directly transfer electrons from NADH to oxygen. Recently, it was reported that the formation of supercomplex In + IIIn + IVn in mice largely depends on their genetic background. However, in this study, we showed that the composition of supercomplex In + IIIn + IVn is well conserved in various mouse and human cell lines. Strikingly, we found that a minimal supercomplex In + IIIn, termed "lowest supercomplex" (LSC) in this study because of its migration at the lowest position close to complex V dimers in blue native polyacrylamide gel electrophoresis, was associated with complex IV to form a supercomplex In + IIIn + IVn in some, but not all of the human and mouse cells. In addition, we observed that the 3697G>A mutation in mitochondrial-encoded NADH dehydrogenase 1 (ND1) in one patient with Leigh's disease specifically affected the assembly of supercomplex In + IIIn + IVn containing LSC, leading to decreased cellular respiration and ATP generation. In conclusion, we showed the existence of LSC In + IIIn + IVn and impairment of this supercomplex causes disease. PMID:27338358

  10. Cell Type-Specific Modulation of Respiratory Chain Supercomplex Organization

    PubMed Central

    Sun, Dayan; Li, Bin; Qiu, Ruyi; Fang, Hezhi; Lyu, Jianxin

    2016-01-01

    Respiratory chain complexes are organized into large supercomplexes among which supercomplex In + IIIn + IVn is the only one that can directly transfer electrons from NADH to oxygen. Recently, it was reported that the formation of supercomplex In + IIIn + IVn in mice largely depends on their genetic background. However, in this study, we showed that the composition of supercomplex In + IIIn + IVn is well conserved in various mouse and human cell lines. Strikingly, we found that a minimal supercomplex In + IIIn, termed “lowest supercomplex” (LSC) in this study because of its migration at the lowest position close to complex V dimers in blue native polyacrylamide gel electrophoresis, was associated with complex IV to form a supercomplex In + IIIn + IVn in some, but not all of the human and mouse cells. In addition, we observed that the 3697G>A mutation in mitochondrial-encoded NADH dehydrogenase 1 (ND1) in one patient with Leigh’s disease specifically affected the assembly of supercomplex In + IIIn + IVn containing LSC, leading to decreased cellular respiration and ATP generation. In conclusion, we showed the existence of LSC In + IIIn + IVn and impairment of this supercomplex causes disease. PMID:27338358