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Sample records for air cell administration

  1. Air cell

    NASA Astrophysics Data System (ADS)

    Okamura, Okiyoshi; Wakasa, Masayuki; Tamanoi, Yoshihito

    1991-04-01

    The present invention relates to an air cell. This air cell provides a compact light-weight power source for model aircraft permitting them to fly for an extended period so that they may be used for such practical purposes as crop dusting, surveying, and photographing. The cell is comprised of a current collector so disposed between a magnesium, zinc, or aluminum alloy cathode and a petroleum graphite anode that it is in contact with the anode. The anode is formed by adding polytetrafluoroethylene dispersion liquid in a mixture of active carbon and graphite powder, pouring the mixture into a mold and heating it to form the anode. It is fabricated by a plurality of anode sections and is formed with at least one hole so that it can provide a cell which is compact in size and light in weight yet is capable of generating a high output. The anode, the cathode, and a separator are wetted by an electrolytic liquid. The electrolyte is continuously supplied through the life of the cell.

  2. Lithium-Air Cell Development

    NASA Technical Reports Server (NTRS)

    Reid, Concha M.; Dobley, Arthur; Seymour, Frasier W.

    2014-01-01

    Lithium-air (Li-air) primary batteries have a theoretical specific capacity of 11,400 Wh/kg, the highest of any common metal-air system. NASA is developing Li-air technology for a Mobile Oxygen Concentrator for Spacecraft Emergencies, an application which requires an extremely lightweight primary battery that can discharge over 24 hours continuously. Several vendors were funded through the NASA SBIR program to develop Li-air technology to fulfill the requirements of this application. New catalysts and carbon cathode structures were developed to enhance the oxygen reduction reaction and increase surface area to improve cell performance. Techniques to stabilize the lithium metal anode surface were explored. Experimental results for prototype laboratory cells are given. Projections are made for the performance of hypothetical cells constructed from the materials that were developed.

  3. Zinc/air cell cathode

    NASA Astrophysics Data System (ADS)

    McEvoy, J. J.

    1986-04-01

    This invention relates to a cathode for an air depolarized cell in which the hydrophobic catalytic cathode contains or in integrally drophobi catalytic cathode contains or is integrally coated with, on the surface adjacent the cell separator, an absorbent material such as the gelling material used in the anode. The absorbent material, integrated with the cathode surface, adheres the separator to the cathode thereby preventing delamination and provides an electrolyte reservoir for the hydrophobic cathode.

  4. Impacts of Western Area Power Administration`s power marketing alternatives on air quality and noise

    SciTech Connect

    Chun, K.C.; Chang, Y.S.; Rabchuk, J.A.

    1995-05-01

    The Western Area Power Administration, which is responsible for marketing electricity produced at the hydroelectric power-generating facilities operated by the Bureau of Reclamation on the Upper Colorado River, has proposed changes in the levels of its commitment (sales) of long-term firm capacity and energy to its customers. This report describes (1) the existing conditions of air resources (climate and meteorology, ambient air quality, and acoustic environment) of the region potentially affected by the proposed action and (2) the methodology used and the results of analyses conducted to assess the potential impacts on air resources of the proposed action and the commitment-level alternatives. Analyses were performed for the potential impacts of both commitment-level alternatives and supply options, which include combinations of electric power purchases and different operational scenarios of the hydroelectric power-generating facilities.

  5. Air-cooled, hydrogen-air fuel cell

    NASA Technical Reports Server (NTRS)

    Shelekhin, Alexander B. (Inventor); Bushnell, Calvin L. (Inventor); Pien, Michael S. (Inventor)

    1999-01-01

    An air-cooled, hydrogen-air solid polymer electrolyte (SPE) fuel cell with a membrane electrode assembly operatively associated with a fluid flow plate having at least one plate cooling channel extending through the plate and at least one air distribution hole extending from a surface of the cathode flow field into the plate cooling channel.

  6. Fuel cell stack with passive air supply

    DOEpatents

    Ren, Xiaoming; Gottesfeld, Shimshon

    2006-01-17

    A fuel cell stack has a plurality of polymer electrolyte fuel cells (PEFCs) where each PEFC includes a rectangular membrane electrode assembly (MEA) having a fuel flow field along a first axis and an air flow field along a second axis perpendicular to the first axis, where the fuel flow field is long relative to the air flow field. A cathode air flow field in each PEFC has air flow channels for air flow parallel to the second axis and that directly open to atmospheric air for air diffusion within the channels into contact with the MEA.

  7. Air breathing direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming

    2002-01-01

    An air breathing direct methanol fuel cell is provided with a membrane electrode assembly, a conductive anode assembly that is permeable to air and directly open to atmospheric air, and a conductive cathode assembly that is permeable to methanol and directly contacting a liquid methanol source.

  8. Air breathing direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming; Gottesfeld, Shimshon

    2002-01-01

    An air breathing direct methanol fuel cell is provided with a membrane electrode assembly, a conductive anode assembly that is permeable to air and directly open to atmospheric air, and a conductive cathode assembly that is permeable to methanol and directly contacting a liquid methanol source. Water loss from the cell is minimized by making the conductive cathode assembly hydrophobic and the conductive anode assembly hydrophilic.

  9. 40 CFR 23.3 - Timing of Administrator's action under Clean Air Act.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Timing of Administrator's action under Clean Air Act. 23.3 Section 23.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL JUDICIAL REVIEW UNDER EPA-ADMINISTERED STATUTES § 23.3 Timing of Administrator's action under Clean Air...

  10. 40 CFR 23.3 - Timing of Administrator's action under Clean Air Act.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Timing of Administrator's action under Clean Air Act. 23.3 Section 23.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL JUDICIAL REVIEW UNDER EPA-ADMINISTERED STATUTES § 23.3 Timing of Administrator's action under Clean Air...

  11. 40 CFR 23.3 - Timing of Administrator's action under Clean Air Act.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Timing of Administrator's action under Clean Air Act. 23.3 Section 23.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL JUDICIAL REVIEW UNDER EPA-ADMINISTERED STATUTES § 23.3 Timing of Administrator's action under Clean Air...

  12. 40 CFR 23.3 - Timing of Administrator's action under Clean Air Act.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Timing of Administrator's action under Clean Air Act. 23.3 Section 23.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL JUDICIAL REVIEW UNDER EPA-ADMINISTERED STATUTES § 23.3 Timing of Administrator's action under Clean Air...

  13. 40 CFR 23.3 - Timing of Administrator's action under Clean Air Act.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Timing of Administrator's action under Clean Air Act. 23.3 Section 23.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL JUDICIAL REVIEW UNDER EPA-ADMINISTERED STATUTES § 23.3 Timing of Administrator's action under Clean Air...

  14. MICROBIOLOGICAL SCREENING OF THE INDOOR AIR QUALITY IN THE POLK COUNTY ADMINISTRATION BUILDING

    EPA Science Inventory

    The report gives results of a microbiological screening of the indoor air quality in the Polk County (Bartow, FL) Administration Building (PCAB), a large, negatively pressured building not known to be biocontaminated. The microbiological screening included bioaerosol, bulk materi...

  15. Air breathing lithium power cells

    SciTech Connect

    Farmer, Joseph C.

    2014-07-15

    A cell suitable for use in a battery according to one embodiment includes a catalytic oxygen cathode; a stabilized zirconia electrolyte for selective oxygen anion transport; a molten salt electrolyte; and a lithium-based anode. A cell suitable for use in a battery according to another embodiment includes a catalytic oxygen cathode; an electrolyte; a membrane selective to molecular oxygen; and a lithium-based anode.

  16. View of the administration building, cell blocks seven and eight, ...

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

    View of the administration building, cell blocks seven and eight, looking from the southwest wall, facing east - Eastern State Penitentiary, 2125 Fairmount Avenue, Philadelphia, Philadelphia County, PA

  17. New clean air efforts face tough challenges, say senators and former EPA administrators

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2012-02-01

    With the U.S. Environmental Protection Agency (EPA) coming under repeated attack from some members of Congress and others for perceived heavy-handed regulatory actions, two moderate U.S. senators and two former EPA administrators recently noted the need for continued measures to improve air quality. However, they also acknowledged the difficulty in moving forward with new legislative efforts to revise the federal Clean Air Act to further reduce air pollution in the current polarized political climate. "Nobody who wants to see constructive changes [to the act] would dare touch it or propose it in the current climate," said former EPA administrator William Reilly at a 23 January forum sponsored by the World Resources Institute. Reilly, who served as EPA administrator from 1989 to 1992, noted that bipartisan congressional support had been key to addressing many environmental problems up until the mid-1990s.

  18. High performance zinc air fuel cell stack

    NASA Astrophysics Data System (ADS)

    Pei, Pucheng; Ma, Ze; Wang, Keliang; Wang, Xizhong; Song, Mancun; Xu, Huachi

    2014-03-01

    A zinc air fuel cell (ZAFC) stack with inexpensive manganese dioxide (MnO2) as the catalyst is designed, in which the circulation flowing potassium hydroxide (KOH) electrolyte carries the reaction product away and acts as a coolant. Experiments are carried out to investigate the characteristics of polarization, constant current discharge and dynamic response, as well as the factors affecting the performance and uniformity of individual cells in the stack. The results reveal that the peak power density can be as high as 435 mW cm-2 according to the area of the air cathode sheet, and the influence factors on cell performance and uniformity are cell locations, filled state of zinc pellets, contact resistance, flow rates of electrolyte and air. It is also shown that the time needed for voltages to reach steady state and that for current step-up or current step-down are both in milliseconds, indicating the ZAFC can be excellently applied to vehicles with rapid dynamic response demands.

  19. Exposure of Mammalian Cells to Air-Pollutant Mixtures at the Air-Liquid Interface

    EPA Science Inventory

    It has been widely accepted that exposure of mammalian cells to air-pollutant mixtures at the air-liquid interface is a more realistic approach than exposing cell under submerged conditions. The VITROCELL systems, are commercially available systems for air-liquid interface expo...

  20. Combustor air flow control method for fuel cell apparatus

    DOEpatents

    Clingerman, Bruce J.; Mowery, Kenneth D.; Ripley, Eugene V.

    2001-01-01

    A method for controlling the heat output of a combustor in a fuel cell apparatus to a fuel processor where the combustor has dual air inlet streams including atmospheric air and fuel cell cathode effluent containing oxygen depleted air. In all operating modes, an enthalpy balance is provided by regulating the quantity of the air flow stream to the combustor to support fuel cell processor heat requirements. A control provides a quick fast forward change in an air valve orifice cross section in response to a calculated predetermined air flow, the molar constituents of the air stream to the combustor, the pressure drop across the air valve, and a look up table of the orifice cross sectional area and valve steps. A feedback loop fine tunes any error between the measured air flow to the combustor and the predetermined air flow.

  1. AIRE deficiency leads to impaired iNKT cell development.

    PubMed

    Lindh, Emma; Rosmaraki, Eleftheria; Berg, Louise; Brauner, Hanna; Karlsson, Mikael C I; Peltonen, Leena; Höglund, Petter; Winqvist, Ola

    2010-02-01

    Autoimmune Polyendocrine Syndrome type I (APS I) is caused by mutations in the Autoimmune Regulator gene (AIRE), and results in the immunological destruction of endocrine organs. Herein we have characterized the CD1d-restricted invariant NKT cells (iNKT) and NK cells in APS I patients and Aire(-/-) mice, two cell populations known to play a role in the regulation of autoimmune disease. We show that the frequency of circulating iNKT cells is reduced in APS I patients compared to healthy controls. In accordance with this, iNKT cells are significantly reduced in the thymus and peripheral organs of Aire(-/-) mice. Bone marrow transfer from wild type donors into lethally irradiated Aire(-/-) recipients led to a decreased iNKT cell population in the liver, suggesting an impaired development of iNKT cells in the absence of Aire expression in radio-resistant cells. In contrast to the iNKT cells, both conventional NK cells and thymus-derived NK cells were unaffected by Aire deficiency and differentiated normally in Aire(-/-) mice. Our results show that expression of Aire in radio-resistant cells is important for the development of iNKT cells, whereas NK cell development and function does not depend on Aire.

  2. Seal tab for a metal-air electrochemical cell

    SciTech Connect

    Oltman, J.E.; Dopp, R.B.; Carpenter, D.D.

    1987-03-10

    This patent describes an only slightly permeable, removable seal tab, having high initial tack, used to cover the air entry ports of a metal-air electrochemical cell between the time the cell is manufactured and the time the cell is used as a source of electrical power. The tab comprises a face stock of biaxially-oriented three-ply polypropylene paper interposed between an acrylic adhesive and a plastic film. A metal-air electrochemical cell is also described wherein a seal tab according to the aforementioned has been mechanically affixed to the cell in such a manner as to cover the air entry port or ports of the cell.

  3. 40 CFR 22.34 - Supplemental rules governing the administrative assessment of civil penalties under the Clean Air...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... administrative assessment of civil penalties under the Clean Air Act. 22.34 Section 22.34 Protection of... Clean Air Act. (a) Scope. This section shall apply, in conjunction with §§ 22.1 through 22.32, in...) of the Clean Air Act, as amended (42 U.S.C. 7413(d), 7524(c), 7545(d), and 7547(d))....

  4. 40 CFR 22.34 - Supplemental rules governing the administrative assessment of civil penalties under the Clean Air...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... administrative assessment of civil penalties under the Clean Air Act. 22.34 Section 22.34 Protection of... Clean Air Act. (a) Scope. This section shall apply, in conjunction with §§ 22.1 through 22.32, in...) of the Clean Air Act, as amended (42 U.S.C. 7413(d), 7524(c), 7545(d), and 7547(d))....

  5. 40 CFR 22.34 - Supplemental rules governing the administrative assessment of civil penalties under the Clean Air...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... administrative assessment of civil penalties under the Clean Air Act. 22.34 Section 22.34 Protection of... Clean Air Act. (a) Scope. This section shall apply, in conjunction with §§ 22.1 through 22.32, in...) of the Clean Air Act, as amended (42 U.S.C. 7413(d), 7524(c), 7545(d), and 7547(d))....

  6. 40 CFR 22.34 - Supplemental rules governing the administrative assessment of civil penalties under the Clean Air...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... administrative assessment of civil penalties under the Clean Air Act. 22.34 Section 22.34 Protection of... Clean Air Act. (a) Scope. This section shall apply, in conjunction with §§ 22.1 through 22.32, in...) of the Clean Air Act, as amended (42 U.S.C. 7413(d), 7524(c), 7545(d), and 7547(d))....

  7. Pressurized solid oxide fuel cell integral air accumular containment

    DOEpatents

    Gillett, James E.; Zafred, Paolo R.; Basel, Richard A.

    2004-02-10

    A fuel cell generator apparatus contains at least one fuel cell subassembly module in a module housing, where the housing is surrounded by a pressure vessel such that there is an air accumulator space, where the apparatus is associated with an air compressor of a turbine/generator/air compressor system, where pressurized air from the compressor passes into the space and occupies the space and then flows to the fuel cells in the subassembly module, where the air accumulation space provides an accumulator to control any unreacted fuel gas that might flow from the module.

  8. Macrophages overexpressing Aire induce CD4+Foxp3+ T cells.

    PubMed

    Sun, Jitong; Fu, Haiying; Wu, Jing; Zhu, Wufei; Li, Yi; Yang, Wei

    2013-01-01

    Aire plays an important role in central immune tolerance by regulating the transcription of thousands of genes. However, the role of Aire in the peripheral immune system is poorly understood. Regulatory T (Treg) cells are considered essential for the maintenance of peripheral tolerance, but the effect of Aire on Treg cells in the peripheral immune system is currently unknown. In this study, we investigated the effects of macrophages overexpressing Aire on CD4+Foxp3+ Treg cells by co-culturing Aire-overexpressing RAW264.7 cells or their supernatant with splenocytes. The results show that macrophages overexpressing Aire enhanced the expression of Foxp3 mRNA and induced different subsets of Treg cells in splenocytes through cell-cell contact or a co-culture supernatants. TGF-β is a key molecule in the increases of CD4+CD45RA+Foxp3hi T cell and activating Treg (aTreg) levels observed following cell‑supernatant co-culturing. Subsets of Treg cells were induced by Aire-overexpressing macrophages, and the manipulation of Treg cells by the targeting of Aire may provide a method for the treatment of inflammatory or autoimmune diseases.

  9. Air pollutant production by algal cell cultures

    NASA Technical Reports Server (NTRS)

    Fong, F.; Funkhouser, E. A.

    1982-01-01

    The production of phytotoxic air pollutants by cultures of Chlorella vulgaris and Euglena gracilis is considered. Algal and plant culture systems, a fumigation system, and ethylene, ethane, cyanide, and nitrogen oxides assays are discussed. Bean, tobacco, mustard green, cantaloupe and wheat plants all showed injury when fumigated with algal gases for 4 hours. Only coleus plants showed any resistance to the gases. It is found that a closed or recycled air effluent system does not produce plant injury from algal air pollutants.

  10. Aire knockdown in medullary thymic epithelial cells affects Aire protein, deregulates cell adhesion genes and decreases thymocyte interaction.

    PubMed

    Pezzi, Nicole; Assis, Amanda Freire; Cotrim-Sousa, Larissa Cotrim; Lopes, Gabriel Sarti; Mosella, Maritza Salas; Lima, Djalma Sousa; Bombonato-Prado, Karina F; Passos, Geraldo Aleixo

    2016-09-01

    We demonstrate that even a partial reduction of Aire mRNA levels by siRNA-induced Aire knockdown (Aire KD) has important consequences to medullary thymic epithelial cells (mTECs). Aire knockdown is sufficient to reduce Aire protein levels, impair its nuclear location, and cause an imbalance in large-scale gene expression, including genes that encode cell adhesion molecules. These genes drew our attention because adhesion molecules are implicated in the process of mTEC-thymocyte adhesion, which is critical for T cell development and the establishment of central self-tolerance. Accordingly, we consider the following: 1) mTECs contribute to the elimination of self-reactive thymocytes through adhesion; 2) Adhesion molecules play a crucial role during physical contact between these cells; and 3) Aire is an important transcriptional regulator in mTECs. However, its role in controlling mTEC-thymocyte adhesion remains unclear. Because Aire controls adhesion molecule genes, we hypothesized that the disruption of its expression could influence mTEC-thymocyte interaction. To test this hypothesis, we used a murine Aire(+) mTEC cell line as a model system to reproduce mTEC-thymocyte adhesion in vitro. Transcriptome analysis of the mTEC cell line revealed that Aire KD led to the down-modulation of more than 800 genes, including those encoding for proteins involved in cell adhesion, i.e., the extracellular matrix constituent Lama1, the CAM family adhesion molecules Vcam1 and Icam4, and those that encode peripheral tissue antigens. Thymocytes co-cultured with Aire KD mTECs had a significantly reduced capacity to adhere to these cells. This finding is the first direct evidence that Aire also plays a role in controlling mTEC-thymocyte adhesion. PMID:27505711

  11. Aire knockdown in medullary thymic epithelial cells affects Aire protein, deregulates cell adhesion genes and decreases thymocyte interaction.

    PubMed

    Pezzi, Nicole; Assis, Amanda Freire; Cotrim-Sousa, Larissa Cotrim; Lopes, Gabriel Sarti; Mosella, Maritza Salas; Lima, Djalma Sousa; Bombonato-Prado, Karina F; Passos, Geraldo Aleixo

    2016-09-01

    We demonstrate that even a partial reduction of Aire mRNA levels by siRNA-induced Aire knockdown (Aire KD) has important consequences to medullary thymic epithelial cells (mTECs). Aire knockdown is sufficient to reduce Aire protein levels, impair its nuclear location, and cause an imbalance in large-scale gene expression, including genes that encode cell adhesion molecules. These genes drew our attention because adhesion molecules are implicated in the process of mTEC-thymocyte adhesion, which is critical for T cell development and the establishment of central self-tolerance. Accordingly, we consider the following: 1) mTECs contribute to the elimination of self-reactive thymocytes through adhesion; 2) Adhesion molecules play a crucial role during physical contact between these cells; and 3) Aire is an important transcriptional regulator in mTECs. However, its role in controlling mTEC-thymocyte adhesion remains unclear. Because Aire controls adhesion molecule genes, we hypothesized that the disruption of its expression could influence mTEC-thymocyte interaction. To test this hypothesis, we used a murine Aire(+) mTEC cell line as a model system to reproduce mTEC-thymocyte adhesion in vitro. Transcriptome analysis of the mTEC cell line revealed that Aire KD led to the down-modulation of more than 800 genes, including those encoding for proteins involved in cell adhesion, i.e., the extracellular matrix constituent Lama1, the CAM family adhesion molecules Vcam1 and Icam4, and those that encode peripheral tissue antigens. Thymocytes co-cultured with Aire KD mTECs had a significantly reduced capacity to adhere to these cells. This finding is the first direct evidence that Aire also plays a role in controlling mTEC-thymocyte adhesion.

  12. Fabrication of VB2/air cells for electrochemical testing.

    PubMed

    Stuart, Jessica; Lopez, Ruben; Lau, Jason; Li, Xuguang; Waje, Mahesh; Mullings, Matthew; Rhodes, Christopher; Licht, Stuart

    2013-01-01

    A technique to investigate the properties and performance of new multi-electron metal/air battery systems is proposed and presented. A method for synthesizing nanoscopic VB2 is presented as well as step-by-step procedure for applying a zirconium oxide coating to the VB2 particles for stabilization upon discharge. The process for disassembling existing zinc/air cells is shown, in addition construction of the new working electrode to replace the conventional zinc/air cell anode with a the nanoscopic VB2 anode. Finally, discharge of the completed VB2/air battery is reported. We show that using the zinc/air cell as a test bed is useful to provide a consistent configuration to study the performance of the high-energy high capacity nanoscopic VB2 anode. PMID:23962835

  13. Experimental myasthenia gravis in Aire-deficient mice: a link between Aire and regulatory T cells.

    PubMed

    Aricha, Revital; Feferman, Tali; Berrih-Aknin, Sonia; Fuchs, Sara; Souroujon, Miriam C

    2012-12-01

    Aire (autoimmune regulator) has a key role in the establishment of tolerance to autoantigens. Aire(-/-) mice present decreased thymic expression of AChR, significantly lower frequencies of regulatory T (T(reg)) cells, and higher expression of Th17 markers, compared to controls. We therefore predicted that Aire(-/-) mice would be more susceptible to induction of experimental autoimmune myasthenia gravis (EAMG). However, when EAMG was induced in young mice, Aire(-/-) mice presented a milder disease that wild-type (WT) controls. In contrast, when EAMG was induced in older mice, Aire(-/-) mice were more severely affected than WT mice. The relative resistance to EAMG in young Aire(-/-) mice correlated with increased numbers of T(reg) cells in their spleens compared to young controls. A similar age-related susceptibility was also observed when EAE was induced in Aire(-/-) mice, suggesting an age-related link among Aire, disease susceptibility, and peripheral T(reg) cells that may be a general feature of autoimmunity.

  14. Air Breathing Direct Methanol Fuel Cell

    DOEpatents

    Ren; Xiaoming

    2003-07-22

    A method for activating a membrane electrode assembly for a direct methanol fuel cell is disclosed. The method comprises operating the fuel cell with humidified hydrogen as the fuel followed by running the fuel cell with methanol as the fuel.

  15. Air side contamination in Solid Oxide Fuel Cell stack testing

    NASA Astrophysics Data System (ADS)

    Schuler, J. Andreas; Gehrig, Christian; Wuillemin, Zacharie; Schuler, Albert J.; Wochele, Joerg; Ludwig, Christian; Hessler-Wyser, Aïcha; Van herle, Jan

    This work aimed to quantify air side contaminants during Solid Oxide Fuel Cell (SOFC) testing in stack configuration. Post-analyses of a long-term test have shown that performance degradation was mainly due to cathode pollutants originated upstream of the cell, therefore their source identification is crucial. The compressed air system, feeding the airflow to the cathode, was investigated by filtering and subsequent chemical analysis of the filters. Hot-air-sampling was redone in situ at the cathode air entry during a new test run to assess the contaminant concentrations in air in SOFC test conditions. In addition, the behavior of SOFC proximal system components, i.e. alloy oxidation, was characterized separately. Besides the investigation of silicon and sulfur contamination, the present work focused on chromium from high-temperature alloys used in Balance-of-Plant (BoP) components in direct contact with the airflow. Concentrations of volatile Cr-species under SOFC testing conditions were compared to Cr-accumulation on the tested cell as well as to Cr-evaporation rates from BoP alloys, which were individually characterized regarding oxidation behavior. Evaporated Cr quantities were found to saturate the air with Cr-vapors at the cathode air-inlet, as confirmed by the in-situ measurement of volatile species in the hot airflow, and correlate well to accumulated Cr in the cell after long term testing. The results of this study suggest guidelines to reduce air side contamination from exogenous sources in SOFC stacks.

  16. Metal-air cell with ion exchange material

    SciTech Connect

    Friesen, Cody A.; Wolfe, Derek; Johnson, Paul Bryan

    2015-08-25

    Embodiments of the invention are related to anion exchange membranes used in electrochemical metal-air cells in which the membranes function as the electrolyte material, or are used in conjunction with electrolytes such as ionic liquid electrolytes.

  17. Annular feed air breathing fuel cell stack

    DOEpatents

    Wilson, Mahlon S.

    1996-01-01

    A stack of polymer electrolyte fuel cells is formed from a plurality of unit cells where each unit cell includes fuel cell components defining a periphery and distributed along a common axis, where the fuel cell components include a polymer electrolyte membrane, an anode and a cathode contacting opposite sides of the membrane, and fuel and oxygen flow fields contacting the anode and the cathode, respectively, wherein the components define an annular region therethrough along the axis. A fuel distribution manifold within the annular region is connected to deliver fuel to the fuel flow field in each of the unit cells. In a particular embodiment, a single bolt through the annular region clamps the unit cells together. In another embodiment, separator plates between individual unit cells have an extended radial dimension to function as cooling fins for maintaining the operating temperature of the fuel cell stack.

  18. Aire Enforces Immune Tolerance by Directing Autoreactive T Cells into the Regulatory T Cell Lineage.

    PubMed

    Malchow, Sven; Leventhal, Daniel S; Lee, Victoria; Nishi, Saki; Socci, Nicholas D; Savage, Peter A

    2016-05-17

    The promiscuous expression of tissue-restricted antigens in the thymus, driven in part by autoimmune regulator (Aire), is critical for the protection of peripheral tissues from autoimmune attack. Aire-dependent processes are thought to promote both clonal deletion and the development of Foxp3(+) regulatory T (Treg) cells, suggesting that autoimmunity associated with Aire deficiency results from two failed tolerance mechanisms. Here, examination of autoimmune lesions in Aire(-/-) mice revealed an unexpected third possibility. We found that the predominant conventional T cell clonotypes infiltrating target lesions express antigen receptors that were preferentially expressed by Foxp3(+) Treg cells in Aire(+/+) mice. Thus, Aire enforces immune tolerance by ensuring that distinct autoreactive T cell specificities differentiate into the Treg cell lineage; dysregulation of this process results in the diversion of Treg cell-biased clonotypes into pathogenic conventional T cells.

  19. A review on air cathodes for zinc-air fuel cells

    NASA Astrophysics Data System (ADS)

    Neburchilov, Vladimir; Wang, Haijiang; Martin, Jonathan J.; Qu, Wei

    This paper reviews the compositions, design and methods of fabrication of air cathodes for alkali zinc-air fuel cells (ZAFCs), one of the few successfully commercialized fuel cells. The more promising compositions for air cathodes are based on individual oxides, or mixtures of such, with a spinel, perovskite, or pyrochlore structure: MnO 2, Ag, Co 3O 4, La 2O 3, LaNiO 3, NiCo 2O 4, LaMnO 3, LaNiO 3, etc. These compositions provide the optimal balance of ORR activity and chemical stability in an alkali electrolyte. The sol-gel and reverse micelle methods supply the most uniform distribution of the catalyst on carbon and the highest catalyst BET surface area. It is shown that the design of the air cathode, including types of carbon black, binding agents, current collectors, Teflon membranes, thermal treatment of the GDL, and catalyst layers, has a strong effect on performance.

  20. Fuel Cells Utilizing Oxygen From Air at Low Pressures

    NASA Technical Reports Server (NTRS)

    Cisar, Alan; Boyer, Chris; Greenwald, Charles

    2006-01-01

    A fuel cell stack has been developed to supply power for a high-altitude aircraft with a minimum of air handling. The fuel cell is capable of utilizing oxygen from ambient air at low pressure with no need for compression. For such an application, it is advantageous to take oxygen from the air (in contradistinction to carrying a supply of oxygen onboard), but it is a challenging problem to design a fuel-cell stack of reasonable weight that can generate sufficient power while operating at reduced pressures. The present fuel-cell design is a response to this challenge. The design features a novel bipolar plate structure in combination with a gas-diffusion structure based on a conductive metal core and a carbon gas-diffusion matrix. This combination makes it possible for the flow fields in the stack to have a large open fraction (ratio between open volume and total volume) to permit large volumes of air to flow through with exceptionally low backpressure. Operations at reduced pressure require a corresponding increase in the volume of air that must be handled to deliver the same number of moles of oxygen to the anodes. Moreover, the increase in the open fraction, relative to that of a comparable prior fuel-cell design, reduces the mass of the stack. The fuel cell has been demonstrated to operate at a power density as high as 105 W/cm2 at an air pressure as low as 2 psia (absolute pressure 14 kPa), which is the atmospheric pressure at an altitude of about 50,000 ft ( 15.2 km). The improvements in the design of this fuel cell could be incorporated into designs of other fuel cells to make them lighter in weight and effective at altitudes higher than those of prior designs. Potential commercial applications for these improvements include most applications now under consideration for fuel cells.

  1. Annular feed air breathing fuel cell stack

    DOEpatents

    Wilson, Mahlon S.; Neutzler, Jay K.

    1997-01-01

    A stack of polymer electrolyte fuel cells is formed from a plurality of unit cells where each unit cell includes fuel cell components defining a periphery and distributed along a common axis, where the fuel cell components include a polymer electrolyte membrane, an anode and a cathode contacting opposite sides of the membrane, and fuel and oxygen flow fields contacting the anode and the cathode, respectively, wherein the components define an annular region therethrough along the axis. A fuel distribution manifold within the annular region is connected to deliver fuel to the fuel flow field in each of the unit cells. The fuel distribution manifold is formed from a hydrophilic-like material to redistribute water produced by fuel and oxygen reacting at the cathode. In a particular embodiment, a single bolt through the annular region clamps the unit cells together. In another embodiment, separator plates between individual unit cells have an extended radial dimension to function as cooling fins for maintaining the operating temperature of the fuel cell stack.

  2. 77 FR 52322 - McClellan Air Force Base Superfund Site Proposed Notice of Administrative Order on Consent

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-29

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY McClellan Air Force Base Superfund Site Proposed Notice of Administrative Order on Consent AGENCY... Base Superfund Site (``Site'') in McClellan, California has been negotiated by the Agency and...

  3. AIRE expressing marginal zone dendritic cells balances adaptive immunity and T-follicular helper cell recruitment.

    PubMed

    Lindmark, Evelina; Chen, Yunying; Georgoudaki, Anna-Maria; Dudziak, Diana; Lindh, Emma; Adams, William C; Loré, Karin; Winqvist, Ola; Chambers, Benedict J; Karlsson, Mikael C I

    2013-05-01

    Autoimmune polyendocrine syndrome Type I (APS I) results in multiple endocrine organ destruction and is caused by mutations in the Autoimmune regulator gene (AIRE). In the thymic stroma, cells expressing the AIRE gene dictate T cell education and central tolerance. Although this function is the most studied, AIRE is also expressed in the periphery in DCs and stromal cells. Still, how AIRE regulated transcription modifies cell behaviour in the periphery is largely unknown. Here we show that AIRE is specifically expressed by 33D1(+) DCs and dictates the fate of antibody secreting cell movement within the spleen. We also found that AIRE expressing 33D1(+) DCs expresses self-antigens as exemplified by the hallmark gene insulin. Also, as evidence for a regulatory function, absence of Aire in 33D1(+) DCs led to reduced levels of the chemokine CXCL12 and increased co-stimulatory properties. This resulted in altered activation and recruitment of T-follicular helper cells and germinal centre B cells. The altered balance leads to a change of the early response to a T cell-dependent antigen in Aire(-/-) mice. These findings add to the understanding of how specific DC subtypes regulate the early responses during T cell-dependent antibody responses within the spleen and further define the role of AIRE in the periphery as regulator of self-antigen expression and lymphocyte migration.

  4. Case study of municipal air pollution policies: Houston's Air Toxic Control Strategy under the White Administration, 2004-2009.

    PubMed

    Bruhl, Rebecca J; Linder, Stephen H; Sexton, Ken

    2013-05-01

    Local government has traditionally played only a minor role in regulating airborne toxic pollutants. However, from 2004 to 2009, the City of Houston implemented a novel, municipality-based air toxics reduction strategy to address what it considered unacceptable health risks and an insufficient regulatory response from state and federal agencies. The city's effort to exert local control over stationary sources of air toxics represents a unique opportunity to study the selection and performance of policy tools and to consider their ramifications for the design of future air pollution control strategies. The results of this case study demonstrate the potential for municipal government to use a combination of cooperative and confrontational policies to stimulate responses from private industry and state and federal regulators as part of a strategy to address local air quality problems.

  5. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  6. Improved alkaline hydrogen/air fuel cells for transportation applications

    SciTech Connect

    McBreen, J; Kissel, G; Kordesch, K V; Kulesa, F; Taylor, E J; Gannon, E; Srinivasan, S

    1980-01-01

    Considerable progress has been made in the last few years on improvement of alkaline air electrodes for air depolarized chlor-alkali cells. Some of these electrodes from Union Carbide Corporation have been evaluated at Brookhaven National Laboratory in alkaline hydrogen/air fuel cells. In initial tests with 289 cm/sup 2/ electrodes, power densities of 100 mW/cm/sup 2/ were obtained at 0.65 V. This compares with power densities of 27 mW/cm/sup 2/ obtained by Kordesch in his vehicle fuel cell in the late sixties. Further improvements in the air electrode flow field yielded power densities of 126 mW/cm/sup 2/ at 0.65 V at an operating temperature of 70/sup 0/C. At 30/sup 0/C, nearly 60% of this power could be obtained at 0.65 V. The 289 cm/sup 2/ cells were units in a 16-cell 0.5 kW module. This module yielded similar power densities, and its power/weight and power/volume are sufficiently attractive for it to be considered as a building block for a fuel cell power plant in a fuel cell/battery hybrid vehicle.

  7. Aire-Overexpressing Dendritic Cells Induce Peripheral CD4⁺ T Cell Tolerance.

    PubMed

    Li, Dongbei; Li, Haijun; Fu, Haiying; Niu, Kunwei; Guo, Yantong; Guo, Chuan; Sun, Jitong; Li, Yi; Yang, Wei

    2015-12-29

    Autoimmune regulator (Aire) can promote the ectopic expression of peripheral tissue-restricted antigens (TRAs) in thymic medullary epithelial cells (mTECs), which leads to the deletion of autoreactive T cells and consequently prevents autoimmune diseases. However, the functions of Aire in the periphery, such as in dendritic cells (DCs), remain unclear. This study's aim was to investigate the effect of Aire-overexpressing DCs (Aire cells) on the functions of CD4⁺ T cells and the treatment of type 1 diabetes (T1D). We demonstrated that Aire cells upregulated the mRNA levels of the tolerance-related molecules CD73, Lag3, and FR4 and the apoptosis of CD4⁺ T cells in STZ-T1D mouse-derived splenocytes. Furthermore, following insulin stimulation, Aire cells decreased the number of CD4⁺ IFN-γ⁺ T cells in both STZ-T1D and WT mouse-derived splenocytes and reduced the expression levels of TCR signaling molecules (Ca(2+) and p-ERK) in CD4⁺ T cells. We observed that Aire cells-induced CD4⁺ T cells could delay the development of T1D. In summary, Aire-expressing DCs inhibited TCR signaling pathways and decreased the quantity of CD4⁺IFN-γ⁺ autoreactive T cells. These data suggest a mechanism for Aire in the maintenance of peripheral immune tolerance and provide a potential method to control autoimmunity by targeting Aire.

  8. Targeting cancer cells with reactive oxygen and nitrogen species generated by atmospheric-pressure air plasma.

    PubMed

    Ahn, Hak Jun; Kim, Kang Il; Hoan, Nguyen Ngoc; Kim, Churl Ho; Moon, Eunpyo; Choi, Kyeong Sook; Yang, Sang Sik; Lee, Jong-Soo

    2014-01-01

    The plasma jet has been proposed as a novel therapeutic method for cancer. Anticancer activity of plasma has been reported to involve mitochondrial dysfunction. However, what constituents generated by plasma is linked to this anticancer process and its mechanism of action remain unclear. Here, we report that the therapeutic effects of air plasma result from generation of reactive oxygen/nitrogen species (ROS/RNS) including H2O2, Ox, OH-, •O2, NOx, leading to depolarization of mitochondrial membrane potential and mitochondrial ROS accumulation. Simultaneously, ROS/RNS activate c-Jun NH2-terminal kinase (JNK) and p38 kinase. As a consequence, treatment with air plasma jets induces apoptotic death in human cervical cancer HeLa cells. Pretreatment of the cells with antioxidants, JNK and p38 inhibitors, or JNK and p38 siRNA abrogates the depolarization of mitochondrial membrane potential and impairs the air plasma-induced apoptotic cell death, suggesting that the ROS/RNS generated by plasma trigger signaling pathways involving JNK and p38 and promote mitochondrial perturbation, leading to apoptosis. Therefore, administration of air plasma may be a feasible strategy to eliminate cancer cells.

  9. Aluminum-air power cell research and development

    NASA Astrophysics Data System (ADS)

    Cooper, J. F.

    1984-12-01

    The wedge-shaped design, of the aluminum-air battery being developed, is mechanically simple and capable of full anode utilization and rapid full or partial recharge. To maintain constant interelectrode separation and to collect anodic current, the cell uses tin-coated copper tracks mounted on removable cassettes. Under gravity feed, slabs of aluminum enter the cell at a continuous and constant rate and gradually assume the wedge shape as they dissolve. Voltage losses at this tin-aluminum junction are 7 mV at 2 kA/m(2). A second-generation wedge cell incorporates air and electrolyte manifolding into individually replaceable air-cathode cassettes. Prototype wedge cells of one design were operated simultaneously with a fluidized-bed crystallizer, which stabilized aluminate concentration and produced a granular aluminum-trihydroxide reaction product. Electrolyte was circulated between the cell and crystallizer, and a hydrocyclone was used to retain particles larger than 0.015 mm within the crystallizer. Air electrodes were tested over simulated vehicle drive systems that include a standby phase in cold, supersaturated electrolyte.

  10. Low-friction coatings for air bearings in fuel cell air compressors

    SciTech Connect

    Ajayi, O. O.; Fenske, G. R.; Erdemir, A.; Woodford, J.; Sitts, J.; Elshot, K.; Griffey, K.

    2000-01-06

    In an effort to reduce fuel consumption and emissions, hybrid vehicles incorporating fuel cell systems are being developed by automotive manufacturers, their suppliers, federal agencies (specifically, the US Department of Energy) and national laboratories. The fuel cell system will require an air management subsystem that includes a compressor/expander. Certain components in the compressor will require innovative lubrication technology in order to reduce parasitic energy losses and improve their reliability and durability. One such component is the air bearing for air turbocompressors designed and fabricated by Meruit, Inc. Argonne National Laboratory recently developed a carbon-based coating with low friction and wear attributes; this near-frictionless-carbon (NFC) coating is a potential candidate for use in turbocompressor air bearings. The authors present here an evaluation of the Argonne coating for air compressor thrust bearings. With two parallel 440C stainless steel discs in unidirectional sliding contact, the NFC reduced the frictional force four times and the wear rate by more than two orders of magnitude. Wear mechanism on the uncoated surface involved oxidation and production of iron oxide debris. Wear occurred on the coated surfaces primarily by a polishing mechanism.

  11. Aluminum-air power cell research and development

    NASA Astrophysics Data System (ADS)

    Cooper, J. F.

    1984-02-01

    An aluminum-air battery is under development with the objective of providing an electric vehicle with the range, acceleration and rapid refueling capability of common automobiles. From tested refuelable cell designs, a wedge-shaped cell was chosen for mechanical simplicity and for its capability of full anode utilization and rapid partial- or full-recharge. The cell uses tin-plated copper tracks to maintain a constant interelectrode separation and to collect anodic current. Rectangular slabs of aluminum enter the cell under gravity feed and gradually assume the wedge shape during dissolution. The feed is constant and continuous and tin/aluminum junction losses are 7 mV at 2 kA/m(2). A second generation wedge cell was developed which incorporates air- and electrolyte-manifolding into individually-replaceable air-cathode cassettes. A prototype wedge cell using replaceable cassettes was operated simultaneously with a crystallizer, which stabilized aluminate concentration and produced a granular aluminum-trihydroxide reaction product. Electrolyte was circulated between cell and fluidized-bed crystallizer, and particles of sizes greater than 0.015 mm were retained within the crystallizer using a hydrocyclone.

  12. Oxide modified air electrode surface for high temperature electrochemical cells

    DOEpatents

    Singh, Prabhakar; Ruka, Roswell J.

    1992-01-01

    An electrochemical cell is made having a porous cermet electrode (16) and a porous lanthanum manganite electrode (14), with solid oxide electrolyte (15) between them, where the lanthanum manganite surface next to the electrolyte contains a thin discontinuous layer of high surface area cerium oxide and/or praseodymium oxide, preferably as discrete particles (30) in contact with the air electrode and electrolyte.

  13. Fuel cells and air quality: A California perspective

    NASA Astrophysics Data System (ADS)

    Lloyd, Alan C.; Leonard, Jonathan H.; George, Ranji

    1994-04-01

    The continuing challenge to improve the quality of urban air, worldwide, provides many opportunities to introduce cleaner technologies into the industrial energy base. The fuel cell is particularly attractive from an environmental viewpoint because of its inherent efficiency, zero or near-zero emissions, and quiet operation. Since 1991, fuel cells have made major institutional strides in being recognized as part of the solution to the major air-pollution problem in Southern California. Fuel cells and hydrogen are now receiving greater attention in the regulatory planning process. This process seeks to identify lower-emitting technologies and fuels that can assist the region in meeting health-based air-quality standards by the year 2010, and provide for a sustainable, health-grounded regional economy as well. Current demonstration projects involving fuel cells and hydrogen are discussed, as well as necessary plans and incentives for infrastructure development - a critical component of fuel-cell commercialization. Finally, an overview is presented of regulatory efforts that are being considered to support early markets for fuel cells.

  14. 32 CFR 806.29 - Administrative processing of Air Force FOIA requests.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... adverse tracking decision in writing. See § 806.27 for sample language for this kind of letter to a...) Contacts with the FOIA Requester. See § 806.27 for samples of language to use in various types of Air Force.... See § 806.27 for samples of language to use in Air Force letters to both the FOIA requester...

  15. Aluminum-air power cell research and development. Progress report

    SciTech Connect

    Cooper, J.F.

    1984-02-22

    An aluminum-air battery is under development with the objective of providing an electric vehicle with the range, acceleration and rapid refueling capability of common automobiles. From tested refuelable cell designs, a wedge-shaped cell was chosen for mechanical simplicity and for its capability of full anode utilization and rapid partial- or full-recharge. The cell uses tin-plated copper tracks to maintain a constant interelectrode separation and to collect anodic current. Rectangular slabs of aluminum enter the cell under gravity feed and gradually assume the wedge shape during dissolution. The feed is constant and continuous and tin/aluminum junction losses are 7 mV at 2 kA/m/sup 2/. A second generation wedge cell has been developed which incorporates air- and electrolyte-manifolding into individually-replaceable air-cathode cassettes. A prototype wedge cell using replaceable cassettes was operated simultaneously with a crystallizer, which stabilized aluminate concentration and produced a granular aluminum-trihydroxide reaction product. Electrolyte was circulated between cell and fluidized-bed crystallizer, and particles of sizes greater than 0.015 mm were retained within the crystallizer using a hydrocyclone. Air electrodes have been tested over simulated vehicle drive cycles. Electrodes using advanced sintering and wet-proofing techniques and catalyzed with a non-noble metal catalyst (CoTMPP) have been operated for over 1400 drive-cycles. Fuel costs of $1.72/kg-Al (installed) were estimated on the basis of model alloy production and distribution costs, leading to a projected operating cost of 8-10 cents/mile, depending on alloy and vehicle drive-train efficiencies. Unalloyed aluminum yields a peak of 4.5 kWh/kg, while an advanced industrial Hall Process and the pilot-plant Alcoa Smelting Process have electrical energy consumptions of 11.3- and 8.3 kWh/kg, respectively.

  16. Issues in Studying Administrative Faculty Salary Equity. AIR 1995 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Brozovsky, Paul V.; McLaughlin, Gerald W.

    Considerations in conducting a study of salary equity for administrative faculty are addressed. The focus is whether there is a systematic difference in salary of administrative faculty based on race, sex, or age after all legitimate factors are removed. After defining the study population, attention is directed to the study model and research…

  17. Faculty Ratings as a Measure of Administrator Quality. AIR Forum 1981 Paper.

    ERIC Educational Resources Information Center

    Hengstler, Dennis D.; And Others

    The reliability, factor structure, and discriminatory power of faculty perceptions of the performance of departmental administrators were investigated, using the Administrator Evaluation Survey (AES) developed at the University of Illinois. Faculty from a major research university in the midwest, a smaller state university in the midwest, and a…

  18. Aluminum-air power cell research and development progress report

    SciTech Connect

    Cooper, J.F.

    1984-12-01

    The wedge-shaped cell design, of the aluminum-air battery being developed, is mechanically simple and capable of full anode utilization and rapid full or partial recharge. To maintain constant interelectrode separation and to collect anodic current, the cell uses tin-coated copper tracks mounted on removable cassettes. Under gravity feed, slabs of aluminum enter the cell at a continuous and constant rate and gradually assume the wedge shape as they dissolve. Voltage losses at this tin-aluminum junction are 7 mV at 2 kA/m/sup 2/. A second-generation wedge cell incorporates air and electrolyte manifolding into individually replaceable air-cathode cassettes. Prototype wedge cells of one design were operated simultaneously with a fluidized-bed crystallizer, which stabilized aluminate concentration and produced a granular aluminum-trihydroxide reaction product. Electrolyte was circulated between the cell and crystallizer, and a hydrocyclone was used to retain particles larger than 0.015 mm within the crystallizer. Air electrodes were tested over simulated vehicle drive systems that include a standby phase in cold, supersaturated electrolyte. Electrodes using advanced sintering and wet-proofing techniques and catalyzed with a nonnoble metal catalyst have been operated over 1500 cycles (a two-year drive life). The fuel costs of aluminum were estimated on the basis of model alloy production and distribution costs, leading to a projected operating cost of 8 to 10 cents per mile, depending on alloy and vehicle drive-train efficiencies. While unalloyed aluminum has a peak electrical energy consumption of 4.5 kWh/kg, the Hall and Alcoa processes consume 11.3 and 8.3 kWh/kg, respectively. The significance of these and other energy-use estimates for the 1990s and beyond is discussed.

  19. Intrathymic administration of hematopoietic progenitor cells enhances T cell reconstitution in ZAP-70 severe combined immunodeficiency

    PubMed Central

    Adjali, Oumeya; Vicente, Rita R.; Ferrand, Christophe; Jacquet, Chantal; Mongellaz, Cédric; Tiberghien, Pierre; Chebli, Karim; Zimmermann, Valérie S.; Taylor, Naomi

    2005-01-01

    Patients with severe combined immunodeficiency (SCID) present with opportunistic infections that are almost universally fatal in infancy. The mainstay treatment for these patients is allogeneic hematopoietic stem cell (HSC) transplantation, but sustained polyclonal T cell reconstitution is too often unsatisfactory. Although transplantation is conventionally performed by i.v. administration of HSC, we hypothesized that an intrathymic strategy would be superior. Indeed, several progenitor cell populations are incapable of homing to the thymus, the major site of T cell differentiation, and it appears that there are extensive time periods during which the thymus is refractory to progenitor cell import. To test this hypothesis, nonconditioned infant ZAP-70-deficient SCID mice were intrathymically injected with WT bone marrow progenitor cells, a procedure accomplished without surgical intervention. Upon intrathymic HSC injection, there was a more rapid T cell differentiation, with mature thymocytes detected by 4 weeks after transplantation. Intrathymic injection of HSC also resulted in significantly higher numbers of peripheral T cells, increased percentages of naïve T cells, and more diverse T cell receptor repertoires. Moreover, T cell reconstitution after intrathymic transplantation was obtained after injection of 10-fold fewer donor HSC. Thus, this intrathymic transplantation approach may improve the outcome of SCID patients by enhancing T cell reconstitution. PMID:16174749

  20. A pound of prevention: Air pollution and the fuel cell

    SciTech Connect

    Johnson, B.L.; Rose, R.

    1996-12-31

    The expanded use of fuel cells in transportation and power generation is an exciting proposition for public health officials because of the potential of this technology to help reduce air pollution levels around the globe. Such work is about prevention -- prevention of air emissions of hazardous substances. Prevention is a key concept in public health. An example is quarantine, which aims to prevent the spread of a disease-causing organism. In the environmental arena, prevention includes cessation of pollution. Air pollution prevention policies also have a practical impact. Sooner or later ideas on technology, especially new technology, must be sold to policy makers, legislators, and eventually the public. Advocating technologies that will improve human health and welfare can be an effective marketing strategy.

  1. Differential Features of AIRE-Induced and AIRE-Independent Promiscuous Gene Expression in Thymic Epithelial Cells.

    PubMed

    St-Pierre, Charles; Trofimov, Assya; Brochu, Sylvie; Lemieux, Sébastien; Perreault, Claude

    2015-07-15

    Establishment of self-tolerance in the thymus depends on promiscuous expression of tissue-restricted Ags (TRA) by thymic epithelial cells (TEC). This promiscuous gene expression (pGE) is regulated in part by the autoimmune regulator (AIRE). To evaluate the commonalities and discrepancies between AIRE-dependent and -independent pGE, we analyzed the transcriptome of the three main TEC subsets in wild-type and Aire knockout mice. We found that the impact of AIRE-dependent pGE is not limited to generation of TRA. AIRE decreases, via non-cell autonomous mechanisms, the expression of genes coding for positive regulators of cell proliferation, and it thereby reduces the number of cortical TEC. In mature medullary TEC, AIRE-driven pGE upregulates non-TRA coding genes that enhance cell-cell interactions (e.g., claudins, integrins, and selectins) and are probably of prime relevance to tolerance induction. We also found that AIRE-dependent and -independent TRA present several distinctive features. In particular, relative to AIRE-induced TRA, AIRE-independent TRA are more numerous and show greater splicing complexity. Furthermore, we report that AIRE-dependent versus -independent TRA project nonredundant representations of peripheral tissues in the thymus.

  2. Indoor air pollution: impact on health and stem cells.

    PubMed

    Ghosh, Shyamasree; Ansar, Waliza

    2014-01-01

    Nearly 2 million people annually die prematurely from various illness contributed by indoor air pollutants (IAP). Such pollutants affect the lungs leading to diseases ranging from bronchial diseases to malignant lung cancer. Stem cells (SC) with the property of self-renewal, pluripotency, and capability of homing into tumors and metastases, have been reported to be promising in treatment of lung cancer. In this review, we have tried to understand the role of components of IAP affect the SC. Although very few studies have been conducted in these lines, existing reports suggest that IAP causes damage to stem cells and their niches thereby reducing successful chances of autologous stem cell transplantation and therapy. The mechanism by which components of IAP affects the functioning of stem cells thus conferring toxicity remains unexplored. The future scope of this review lies in revealing answer to underlying questions of repair and modulation of stem cells in therapeutic treatment of lung diseases.

  3. Air electrode composition for solid oxide fuel cell

    DOEpatents

    Kuo, Lewis; Ruka, Roswell J.; Singhal, Subhash C.

    1999-01-01

    An air electrode composition for a solid oxide fuel cell is disclosed. The air electrode material is based on lanthanum manganite having a perovskite-like crystal structure ABO.sub.3. The A-site of the air electrode composition comprises a mixed lanthanide in combination with rare earth and alkaline earth dopants. The B-site of the composition comprises Mn in combination with dopants such as Mg, Al, Cr and Ni. The mixed lanthanide comprises La, Ce, Pr and, optionally, Nd. The rare earth A-site dopants preferably comprise La, Nd or a combination thereof, while the alkaline earth A-site dopant preferably comprises Ca. The use of a mixed lanthanide substantially reduces raw material costs in comparison with compositions made from high purity lanthanum starting materials. The amount of the A-site and B-site dopants is controlled in order to provide an air electrode composition having a coefficient of thermal expansion which closely matches that of the other components of the solid oxide fuel cell.

  4. Air electrode composition for solid oxide fuel cell

    DOEpatents

    Kuo, L.; Ruka, R.J.; Singhal, S.C.

    1999-08-03

    An air electrode composition for a solid oxide fuel cell is disclosed. The air electrode material is based on lanthanum manganite having a perovskite-like crystal structure ABO{sub 3}. The A-site of the air electrode composition comprises a mixed lanthanide in combination with rare earth and alkaline earth dopants. The B-site of the composition comprises Mn in combination with dopants such as Mg, Al, Cr and Ni. The mixed lanthanide comprises La, Ce, Pr and, optionally, Nd. The rare earth A-site dopants preferably comprise La, Nd or a combination thereof, while the alkaline earth A-site dopant preferably comprises Ca. The use of a mixed lanthanide substantially reduces raw material costs in comparison with compositions made from high purity lanthanum starting materials. The amount of the A-site and B-site dopants is controlled in order to provide an air electrode composition having a coefficient of thermal expansion which closely matches that of the other components of the solid oxide fuel cell. 3 figs.

  5. Modeling and Analysis of Aluminum/Air Fuel Cell

    NASA Astrophysics Data System (ADS)

    Leon, Armando J.

    The technical and scientific challenges to provide reliable sources energy for US and global economy are enormous tasks, and especially so when combined with strategic and recent economic concerns of the last five years. It is clear that as part of the mix of energy sources necessary to deal with these challenges, fuel cells technology will play critical or even a central role. The US Department of Energy, as well as a number of the national laboratories and academic institutions have been aware of the importance such technology for some time. Recently, car manufacturers, transportation experts, and even utilities are paying attention to this vital source of energy for the future. In this thesis, a review of the main fuel cell technologies is presented with the focus on the modeling, and control of one particular and promising fuel cell technology, aluminum air fuel cells. The basic principles of this fuel cell technology are presented. A major part of the study consists of a description of the electrochemistry of the process, modeling, and simulations of aluminum air FC using Matlab Simulink(TM). The controller design of the proposed model is also presented. In sequel, a power management unit is designed and analyzed as an alternative source of power. Thus, the system commutes between the fuel cell output and the alternative power source in order to fulfill a changing power load demand. Finally, a cost analysis and assessment of this technology for portable devices, conclusions and future recommendations are presented.

  6. Aluminum-air power cell, a progress report

    SciTech Connect

    Maimoni, A.

    1985-03-01

    We are developing the Aluminum-Air Power Cell as a power source for general purpose electric vehicles. Program developments since the 1983 IECEC meeting and more recent reviews are summarized. Estimates of its energy efficiency, using coal as the primary energy source, indicate it is substantially better than the internal combustion engine using synthetic fuels derived from coal. With improved materials it is likely to approach the overall energy efficiency of rechargeable battery systems. Three experiments involving a 600-cm/sup 2/ wedge cell coupled to a crystallizer and a hydrocyclone are described. Substantial progress has been made in the development of the air cathode and aluminum anode materials. The status of various system components is summarized. Crystallization experiments indicate secondary nucleation of small particles can be controlled by operation of the crystallizer at 80/sup 0/C and agglomeration of fine particles occurs readily under low shear conditions.

  7. Metal-air cell with performance enhancing additive

    SciTech Connect

    Friesen, Cody A; Buttry, Daniel

    2015-11-10

    Systems and methods drawn to an electrochemical cell comprising a low temperature ionic liquid comprising positive ions and negative ions and a performance enhancing additive added to the low temperature ionic liquid. The additive dissolves in the ionic liquid to form cations, which are coordinated with one or more negative ions forming ion complexes. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. The ion complexes improve oxygen reduction thermodynamics and/or kinetics relative to the ionic liquid without the additive.

  8. High-Altitude Air Mass Zero Calibration of Solar Cells

    NASA Technical Reports Server (NTRS)

    Woodyard, James R.; Snyder, David B.

    2005-01-01

    Air mass zero calibration of solar cells has been carried out for several years by NASA Glenn Research Center using a Lear-25 aircraft and Langley plots. The calibration flights are carried out during early fall and late winter when the tropopause is at the lowest altitude. Measurements are made starting at about 50,000 feet and continue down to the tropopause. A joint NASA/Wayne State University program called Suntracker is underway to explore the use of weather balloon and communication technologies to characterize solar cells at elevations up to about 100 kft. The balloon flights are low-cost and can be carried out any time of the year. AMO solar cell characterization employing the mountaintop, aircraft and balloon methods are reviewed. Results of cell characterization with the Suntracker are reported and compared with the NASA Glenn Research Center aircraft method.

  9. 32 CFR 806.29 - Administrative processing of Air Force FOIA requests.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... criteria in appropriate cases (when requester asks for fee waiver/reduction). (7) Find the responsive Air... and statements to the FOIA office. (ii) If the OPRs find no responsive records, or if the OPRs desire... requested, the requester is advised if the request will be expedited or not. If the request is found to...

  10. 32 CFR 806.29 - Administrative processing of Air Force FOIA requests.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... multitrack FOIA requests.) Note: Requesters have a right to appeal an adverse tracking decision (for example... adverse tracking decision in writing. See § 806.27 for sample language for this kind of letter to a.... Include in the cover letter forwarding the appeal to the Secretary of the Air Force the name, phone...

  11. 32 CFR 806.29 - Administrative processing of Air Force FOIA requests.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... multitrack FOIA requests.) Note: Requesters have a right to appeal an adverse tracking decision (for example... adverse tracking decision in writing. See § 806.27 for sample language for this kind of letter to a.... Include in the cover letter forwarding the appeal to the Secretary of the Air Force the name, phone...

  12. 32 CFR 806.29 - Administrative processing of Air Force FOIA requests.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... multitrack FOIA requests.) Note: Requesters have a right to appeal an adverse tracking decision (for example... adverse tracking decision in writing. See § 806.27 for sample language for this kind of letter to a.... Include in the cover letter forwarding the appeal to the Secretary of the Air Force the name, phone...

  13. 75 FR 48627 - Approval and Promulgation of Air Quality Implementation Plans; Delaware; Administrative and Non...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-11

    ...; Administrative and Non-Substantive Changes to Existing Delaware SIP Regulations AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY: EPA proposes to approve the State Implementation Plan (SIP... Implementation Plan (SIP). In the Final Rules section of this Federal Register, EPA is approving the State's...

  14. The Role of Institutional Research in Data Administration and Management. AIR 1986 Annual Forum Paper.

    ERIC Educational Resources Information Center

    McKinney, Richard L.; And Others

    New roles for college institutional researchers in the area of data administration and management that have resulted from developments in computer technology are reviewed. These developments include easily accessed databases, user-friendly software, and powerful and inexpensive hardware. The growing demand for data, combined with a general lack of…

  15. Evaluation of Administrators by Subordinates: A Cafeteria Approach. AIR 1986 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Budig, Jeanne E.

    The use and refinement of an innovative administrative evaluation system that has been operational at Vincennes University Junior College (Indiana) for 5 years are described. All professional university employees are annually given the opportunity to evaluate all personnel with supervisory responsibility who are above them in the chain of command.…

  16. Zinc/air fuel cell for electric vehicles

    SciTech Connect

    Cherepy, N. J.; Krueger, R.; Cooper, J. F.

    1999-01-01

    We are conducting tests of an advanced zinc/air fuel cell design to determine effectiveness in various commercial applications. Our 322-cm2 cell uses gravity-fed zinc pellets as the anode, 12 M KOH electrolyte, and an air cathode catalyzed by a cobalt-porphyrin complex on carbon black. A single 322 cm2 cell runs at a standard operating power of 38 W (1200 W/m2) at 39 A (1245 A/m2) and 0.96 V with a power density of 2400 W/m2 at 0.67 V. With improved current collection hardware, already demonstrated in the laboratory, power generation increases to -3600 W/m2 at 1V. We conducted a 50-hour test in which a cell generated 587 Ah and 569 Wh. The power that may be generated increases by a factor of 2.5 between T = 28 °C and 52 °C. Electrolyte capacity, without stabilization additives, was measured at 147 Ah/L

  17. A biofuel cell harvesting energy from glucose-air and fruit juice-air.

    PubMed

    Liu, Ying; Dong, Shaojun

    2007-11-30

    The membraneless biofuel cell (BFC) is facile prepared based on glucose oxidase and laccase as anodic and cathodic catalyst, respectively, by using 1,1'-dicarboxyferrocene as the mediators of both anode and cathode. The BFC can work by taking glucose as fuel in air-saturated solution, in which air serves as the oxidizer of the cathode. More interestingly, the fruit juice containing glucose, e.g. grape, banana or orange juice as the fuels substituting for glucose can make the BFC work. The BFC shows several advantages which have not been reported to our knowledge: (1) it is membraneless BFC which can work with same mediator on both anode and cathode; (2) fruit juice can act as fuels of BFCs substituting for usually used glucose; (3) especially, the orange juice can greatly enhance the power output rather than that of glucose, grape or banana juice. Besides, the facile and simple preparation procedure and easy accessibility of fruit juice as well as air being whenever and everywhere imply that our system has promising potential for the development and practical application of BFCs.

  18. Polyphenol administration impairs T-cell proliferation by imprinting a distinct dendritic cell maturational profile.

    PubMed

    Delvecchio, Francesca Romana; Vadrucci, Elisa; Cavalcanti, Elisabetta; De Santis, Stefania; Kunde, Dale; Vacca, Michele; Myers, Jay; Allen, Frederick; Bianco, Giusy; Huang, Alex Y; Monsurro, Vladia; Santino, Angelo; Chieppa, Marcello

    2015-09-01

    Currently little is known as to how nutritionally derived compounds may affect dendritic cell (DC) maturation and potentially prevent inappropriate inflammatory responses that are characteristic of chronic inflammatory syndromes. Previous observations have demonstrated that two polyphenols quercetin and piperine delivered through reconstituted oil bodies (ROBs-QP) can influence DC maturation in response to LPS leading to a modulated inflammatory response. In the present study, we examined the molecular effects of ROBs-QP exposure on DC differentiation in mice and identified a unique molecular signature in response to LPS administration that potentially modulates DC maturation and activity in inflammatory conditions. Following LPS administration, ROBs-QP-exposed DCs expressed an altered molecular profile as compared with control DCs, including cytokine and chemokine production, chemokine receptor repertoire, and antigen presentation ability. In vivo ROBs-QP administration suppresses antigen-specific T-cell division in the draining lymph nodes resulting from a reduced ability to create stable immunological synapse. Our data demonstrate that polyphenols exposure can drive DCs toward a new anti-inflammatory molecular profile capable of dampening the inflammatory response, highlighting their potential as complementary nutritional approaches in the treatment of chronic inflammatory syndromes. PMID:26096294

  19. Systemic Administration of Tolerogenic Dendritic Cells Ameliorates Murine Inflammatory Arthritis

    PubMed Central

    Healy, Louise J; Collins, Helen L; Thompson, Stephen J

    2008-01-01

    The expression of various cell surface molecules and the production of certain cytokines are important mechanisms by which dendritic cells (DC) are able to bias immune responses. This paper describes the effects of the inflammatory cytokine tumor necrosis factor (TNF)-α on DC phenotype and function. TNF-α treatment resulted in upregulation of MHC class II and CD86 in the absence of increased cell surface CD40 and CD80 or the production of IL-12. Additionally TNF-α treated cells were able to bias T cell responses towards an anti-inflammatory profile. On a note of caution this tolerogenic phenotype of the DC was not stable upon subsequent TLR-4 ligation as a 4 hour pulse of the TNF-α treated DC with lipopolysaccharide (LPS) resulted in the restoration of IL-12 production and an enhancement of their T cell stimulatory capacity which resulted in an increased IFN-γ production. However, TNF-α treated DC, when administered in vivo, were shown to ameliorate disease in collagen induced arthritis, an experimental model of inflammatory joint disease. Mice receiving TNF-α treated DC but not LPS matured DC had a delayed onset, and significantly reduced severity, of arthritis. Disease suppression was associated with reduced levels of collagen specific IgG2a and decreased inflammatory cell infiltration into affected joints. In summary the treatment of DC with TNF-α generates an antigen presenting cell with a phenotype that can reduce the pro-inflammatory response and direct the immune system towards a disease modifying, anti-inflammatory state. PMID:19156221

  20. Simultaneous Exposure to Multiple Air Pollutants Influences Alveolar Epithelial Cell Ion Transport

    EPA Science Inventory

    Purpose. Air pollution sources generally release multiple pollutants simultaneously and yet, research has historically focused on the source-to-health linkages of individual air pollutants. We recently showed that exposure of alveolar epithelial cells to a combination of particul...

  1. Temporal lineage tracing of Aire-expressing cells reveals a requirement for Aire in their maturation program.

    PubMed

    Nishikawa, Yumiko; Nishijima, Hitoshi; Matsumoto, Minoru; Morimoto, Junko; Hirota, Fumiko; Takahashi, Satoru; Luche, Hervé; Fehling, Hans Joerg; Mouri, Yasuhiro; Matsumoto, Mitsuru

    2014-03-15

    Understanding the cellular dynamics of Aire-expressing lineage(s) among medullary thymic epithelial cells (AEL-mTECs) is essential for gaining insight into the roles of Aire in establishment of self-tolerance. In this study, we monitored the maturation program of AEL-mTECs by temporal lineage tracing, in which bacterial artificial chromosome transgenic mice expressing tamoxifen-inducible Cre recombinase under control of the Aire regulatory element were crossed with reporter strains. We estimated that the half-life of AEL-mTECs subsequent to Aire expression was ∼7-8 d, which was much longer than that reported previously, owing to the existence of a post-Aire stage. We found that loss of Aire did not alter the overall lifespan of AEL-mTECs, inconsistent with the previous notion that Aire expression in medullary thymic epithelial cells (mTECs) might result in their apoptosis for efficient cross-presentation of self-antigens expressed by AEL-mTECs. In contrast, Aire was required for the full maturation program of AEL-mTECs, as exemplified by the lack of physiological downregulation of CD80 during the post-Aire stage in Aire-deficient mice, thus accounting for the abnormally increased CD80(high) mTECs seen in such mice. Of interest, increased CD80(high) mTECs in Aire-deficient mice were not mTEC autonomous and were dependent on cross-talk with thymocytes. These results further support the roles of Aire in the differentiation program of AEL-mTECs.

  2. Cadmium administration affects circulatory mononuclear cells in rats.

    PubMed

    Djokic, Jelena; Popov Aleksandrov, Aleksandra; Ninkov, Marina; Mirkov, Ivana; Zolotarevski, Lidija; Kataranovski, Dragan; Kataranovski, Milena

    2015-01-01

    Although numerous investigations have demonstrated a direct effect of cadmium (Cd) on peripheral blood mononuclear cell (PBMC) activity in humans, there is virtually no data concerning the in vivo impact of this metal on circulatory mononuclear cells. In this study, the effects of a sub-lethal Cd (1 mg/kg) dose were examined in rats 48 h following a single intraperitoneal injection. Cd treatment resulted in increased total peripheral blood leukocyte levels; however, decreases in PBMC numbers were seen. These changes coincided with an accumulation of mononuclear cells in the lungs and an increase in mononuclear cells expressing CD11b. A lack of effect of Cd on spontaneous nitric oxide (NO) production and on iNOS mRNA levels in the PBMC was also noted. Differential effects of Cd on PBMC inflammatory cytokine (IL-1β, TNFα, IL-6, IFNγ, and IL-17) gene expression and production were also seen. Specifically, except for IL-1β (levels increased), there were decreases (relative to controls) in mRNA levels for all the other cytokines examined. While there were no Cd treatment-related changes in spontaneous production of the cytokines assessed, there seemed to be a trend (p = 0.06) toward a decrease in spontaneous IL-6 release. When these harvested cells were stimulated ex vivo, there was no effect from Cd exposure on LPS-stimulated IL-1β and TNFα or on ConA-stimulated IFNγ or IL-17 production, but a decrease in IL-6 production in response to LPS was, again, noted. A preliminary study with a lower Cd dose (0.5 mg/kg) revealed some of the same outcomes noted here (mononuclear cell infiltration into lungs, increases in PBMC IL-1β mRNA levels), but differential (increased IL-17 mRNA levels) or newly detected outcomes (increased levels of IL-1α mRNA) as well. The described effects of the single in vivo exposure to Cd on PBMC might contribute to a better overall understanding of the immunomodulatory potential of this environmental contaminant.

  3. Progress in Assessing Air Pollutant Risks from In Vitro Exposures: Matching Ozone Dose and Effect in Human Air Way Cells

    EPA Science Inventory

    In vitro exposures to air pollutants could, in theory, facilitate a rapid and detailed assessment of molecular mechanisms of toxicity. However, it is difficult to ensure that the dose of a gaseous pollutant to cells in tissue culture is similar to that of the same cells during in...

  4. Application of AirCell Cellular AMPS Network and Iridium Satellite System Dual Mode Service to Air Traffic Management

    NASA Technical Reports Server (NTRS)

    Shamma, Mohammed A.

    2004-01-01

    The AirCell/Iridium dual mode service is evaluated for potential applications to Air Traffic Management (ATM) communication needs. The AirCell system which is largely based on the Advanced Mobile Phone System (AMPS) technology, and the Iridium FDMA/TDMA system largely based on the Global System for Mobile Communications(GSM) technology, can both provide communication relief for existing or future aeronautical communication links. Both have a potential to serve as experimental platforms for future technologies via a cost effective approach. The two systems are well established in the entire CONUS and globally hence making it feasible to utilize in all regions, for all altitudes, and all classes of aircraft. Both systems have been certified for air usage. The paper summarizes the specifications of the AirCell/Iridium system, as well as the ATM current and future links, and application specifications. the paper highlights the scenarios, applications, and conditions under which the AirCell/Iridium technology can be suited for ATM Communication.

  5. DESIGN NOTE: Measuring the residual air pressure in triple-point-of-water cells

    NASA Astrophysics Data System (ADS)

    White, D. R.

    2004-01-01

    Residual gas pressure is one of the factors influencing the temperature realized by triple-point-of-water cells. This note describes a simple procedure for measuring and correcting for the residual air pressure in sealed cells. The procedure is applicable to any cell with a McLeod-gauge extension or sufficient remnant 'seal-off' tube to trap an air bubble.

  6. Mechanically refuelable zinc/air electric vehicle cells

    NASA Astrophysics Data System (ADS)

    Noring, J.; Gordon, S.; Maimoni, A.; Spragge, M.; Cooper, J. F.

    1992-12-01

    Refuelable zinc/air batteries have long been considered for motive as well as stationary power because of a combination of high specific energy, low initial cost, and the possibility of mechanical recharge by electrolyte exchange and additions of metallic zinc. In this context, advanced slurry batteries, stationary packed bed cells, and batteries offering replaceable cassettes have been reported recently. The authors are developing self-feeding, particulate-zinc/air batteries for electric vehicle applications. Emissionless vehicle legislation in California motivated efforts to consider a new approach to providing an electric vehicle with long range (400 km), rapid refueling (10 minutes) and highway safe acceleration - factors which define the essential functions of common automobiles. Such an electric vehicle would not compete with emerging secondary battery vehicles in specialized applications (commuting vehicles, delivery trucks). Rather, different markets would be sought where long range or rapid range extension are important. Examples are: taxis, continuous-duty fork-lift trucks and shuttle busses, and general purpose automobiles having modest acceleration capabilities. In the long range, a mature fleet would best use regional plants to efficiently recover zinc from battery reaction products. One option would be to use chemical/thermal reduction to recover the zinc. The work described focuses on development of battery configurations which efficiently and completely consume zinc particles, without clogging or changing discharge characteristics.

  7. Mechanically refuelable zinc/air electric vehicle cells

    SciTech Connect

    Noring, J.; Gordon, S.; Maimoni, A.; Spragge, M.; Cooper, J.F.

    1992-12-01

    Refuelable zinc/air batteries have long been considered for motive as well as stationary power because of a combination of high specific energy, low initial cost, and the possibility of mechanical recharge by electrolyte exchange and additions of metallic zinc. In this context, advanced slurry batteries, stationary packed bed cells and batteries offering replaceable cassettes have been reported recently. The authors are developing self-feeding, particulate-zinc/air batteries for electric vehicle applications. Emissionless vehicle legislation in California motivated efforts to consider a new approach to providing an electric vehicle with long range (400 km), rapid refueling (10 minutes) and highway safe acceleration -- factors which define the essential functions of common automobiles. Such a electric vehicle would not compete with emerging secondary battery vehicles in specialized applications (commuting vehicles, delivery trucks). Rather, different markets would be sought where long range or rapid range extension are important. Examples are: taxis, continuous-duty fork-lift trucks and shuttle busses, and general purpose automobiles having modest acceleration capabilities. In the long range, a mature fleet would best use regional plants to efficiently recover zinc from battery reaction products. One option would be to use chemical/thermal reduction to recover the zinc. The work described in this report focuses on development of battery configurations which efficiently and completely consume zinc particles, without clogging or changing discharge characteristics.

  8. Aluminum-air power cell: The M4-cell assembly and initial tests

    NASA Astrophysics Data System (ADS)

    Maimoni, A.; Muelder, S. A.; Hui, W. C.

    1985-10-01

    We fabricated, assembled, and tested the modular, wedge-shaped M4 Aluminum-Air Power Cell in a system with a fluidized-bed crystallizer and hydrocyclone separator. Two M4-cell experiments validated the design premises and indicated predictable performance. The combined duration of the M4-1 and M4-2 experiments was almost 9 h. Conductive epoxy bonds are inadequate for bonding the air-cathode metal screen to current collectors; soldered joints using low melting (93C) Indium solder performed satisfactorily. Both experiments were terminated because of problems directly traceable to metallic tin deposited by the stannate corrosion inhibitor. Apart from problems caused by metallic tin, the M4-2 test system performed very satisfactorily. Individual cell pods are readily assembled into single or multicell stacks; it is easy to disassemble the cells after a run to determine cell condition. Air-cathode assembly is the most cumbersome aspect of the M4 cell. We obtained valuable information regarding the evolution of particle-size distribution. We did not observe substantial agglomeration of the smaller crystals. A simple model of secondary nucleation gave a reasonably good fit to the secondary nucleation observed in the M3-3 experiment.

  9. Optimum design of bipolar plates for separate air flow cooling system of PEM fuel cells stacks

    NASA Astrophysics Data System (ADS)

    Franco, Alessandro

    2015-12-01

    The paper discusses about thermal management of PEM fuel cells. The objective is to define criteria and guidelines for the design of the air flow cooling system of fuel cells stacks for different combination of power density, bipolar plates material, air flow rate, operating temperature It is shown that the optimization of the geometry of the channel permits interesting margins for maintaining the use of separate air flow cooling systems for high power density PEM fuel cells.

  10. Aire promotes the self-renewal of embryonic stem cells through Lin28.

    PubMed

    Bin, Gu; Jiarong, Zhang; Shihao, Wang; Xiuli, Song; Cheng, Xu; Liangbiao, Chen; Ming, Zhang

    2012-10-10

    Abstract Autoimmune regulator (Aire) is one of the most well-characterized molecules in autoimmunity, but its function outside the immune system is largely unknown. The recent discovery of Aire expression in stem cells and early embryonic cells and its function in the self-renewal of embryonic stem (ES) cells highlight the importance of Aire in these cells. In this study, we present evidence that Aire promotes the expression of the pluripotent factor Lin28 and the self-renewal of ES cells. We presented the first evidence that the let-7 microRNA family contributed to the self-renewal promoting effect of Aire on ES cells. Moreover, we showed that Aire and Lin28 are co-expressed in the genital ridge, oocytes, and cleavage-stage embryos, and the expression level of Lin28 is correlated with the expression level of Aire. Although it is widely considered to be a promiscuous gene expression activator, these results indicated that Aire promotes the self-renewal of ES cells through a specific pathway (i.e., the activation of Lin28 and the inhibition of the let-7 microRNA family). The correlation between Aire and Lin28 expression in germ cells and early embryos indicated an in vivo function for Aire in toti- and pluripotent stem cells. This study presents the first molecular pathway that incorporates Aire into the pluripotency network. Moreover, it presents the first evidence that microRNAs contribute to the regulatory function of Aire and highlights a novel function of Aire in stem cell biology and reproduction. These functions reveal novel perspectives for studying the molecular mechanisms behind the establishment and sustenance of pluripotent identity.

  11. Lineage tracing and cell ablation identify a post-Aire-expressing thymic epithelial cell population.

    PubMed

    Metzger, Todd C; Khan, Imran S; Gardner, James M; Mouchess, Maria L; Johannes, Kellsey P; Krawisz, Anna K; Skrzypczynska, Katarzyna M; Anderson, Mark S

    2013-10-17

    Thymic epithelial cells in the medulla (mTECs) play a critical role in enforcing central tolerance through expression and presentation of tissue-specific antigens (TSAs) and deletion of autoreactive thymocytes. TSA expression requires autoimmune regulator (Aire), a transcriptional activator present in a subset of mTECs characterized by high CD80 and major histocompatibility complex II expression and a lack of potential for differentiation or proliferation. Here, using an Aire-DTR transgenic line, we show that short-term ablation specifically targets Aire(+) mTECs, which quickly undergo RANK-dependent recovery. Repeated ablation also affects Aire(-) mTECs, and using an inducible Aire-Cre fate-mapping system, we find that this results from the loss of a subset of mTECs that showed prior expression of Aire, maintains intermediate TSA expression, and preferentially migrates toward the center of the medulla. These results clearly identify a distinct stage of mTEC development and underscore the diversity of mTECs that play a key role in maintaining tolerance.

  12. Elimination of progressive mammary cancer by repeated administrations of chimeric antigen receptor-modified T cells.

    PubMed

    Globerson-Levin, Anat; Waks, Tova; Eshhar, Zelig

    2014-05-01

    Continuous oncogenic processes that generate cancer require an on-going treatment approach to eliminate the transformed cells, and prevent their further development. Here, we studied the ability of T cells expressing a chimeric antibody-based receptor (CAR) to offer a therapeutic benefit for breast cancer induced by erbB-2. We tested CAR-modified T cells (T-bodies) specific to erbB-2 for their antitumor potential in a mouse model overexpressing a human erbB-2 transgene that develops mammary tumors. Comparing the antitumor reactivity of CAR-modified T cells under various therapeutic settings, either prophylactic, prior to tumor development, or therapeutically. We found that repeated administration of CAR-modified T cells is required to eliminate spontaneously developing mammary cancer. Systemic, as well as intratumoral administered CAR-modified T cells accumulated at tumor sites and eventually eliminated the malignant cells. Interestingly, within a few weeks after a single CAR T cells' administration, and rejection of primary lesion, tumors usually relapsed both in treated mammary gland and at remote sites; however, repeated injections of CAR-modified T cells were able to control the secondary tumors. Since spontaneous tumors can arise repeatedly, especially in the case of syndromes characterized by specific susceptibility to cancer, multiple administrations of CAR-modified T cells can serve to control relapsing disease.

  13. AIRE is not essential for the induction of human tolerogenic dendritic cells.

    PubMed

    Crossland, Katherine L; Abinun, Mario; Arkwright, Peter D; Cheetham, Timothy D; Pearce, Simon H; Hilkens, Catharien M U; Lilic, Desa

    2016-06-01

    Loss-of-function mutations of the Autoimmune Regulator (AIRE) gene results in organ-specific autoimmunity and disease Autoimmune Polyendocrinopathy type 1 (APS1)/Autoimmune Polyendocrinopathy Candidiasis Ectodermal Dystrophy (APECED). The AIRE protein is crucial in the induction of central tolerance, promoting ectopic expression of tissue-specific antigens in medullary thymic epithelial cells and enabling removal of self-reactive T-cells. AIRE expression has recently been detected in myeloid dendritic cells (DC), suggesting AIRE may have a significant role in peripheral tolerance. DC stimulation of T-cells is critical in determining the initiation or lack of an immune response, depending on the pattern of costimulation and cytokine production by DCs, defining immunogenic/inflammatory (inflDC) and tolerogenic (tolDC) DC. In AIRE-deficient patients and healthy controls, we validated the role of AIRE in the generation and function of monocyte-derived inflDC and tolDCs by determining mRNA and protein expression of AIRE and comparing activation markers (HLA-DR/DP/DQ,CD83,CD86,CD274(PDL-1),TLR-2), cytokine production (IL-12p70,IL-10,IL-6,TNF-α,IFN-γ) and T-cell stimulatory capacity (mixed lymphocyte reaction) of AIRE+ and AIRE- DCs. We show for the first time that: (1) tolDCs from healthy individuals express AIRE; (2) AIRE expression is not significantly higher in tolDC compared to inflDC; (3) tolDC can be generated from APECED patient monocytes and (4) tolDCs lacking AIRE retain the same phenotype and reduced T-cell stimulatory function. Our findings suggest that AIRE does not have a role in the induction and function of monocyte-derived tolerogenic DC in humans, but these findings do not exclude a role for AIRE in peripheral tolerance mediated by other cell types. PMID:26912174

  14. AIRE is not essential for the induction of human tolerogenic dendritic cells.

    PubMed

    Crossland, Katherine L; Abinun, Mario; Arkwright, Peter D; Cheetham, Timothy D; Pearce, Simon H; Hilkens, Catharien M U; Lilic, Desa

    2016-06-01

    Loss-of-function mutations of the Autoimmune Regulator (AIRE) gene results in organ-specific autoimmunity and disease Autoimmune Polyendocrinopathy type 1 (APS1)/Autoimmune Polyendocrinopathy Candidiasis Ectodermal Dystrophy (APECED). The AIRE protein is crucial in the induction of central tolerance, promoting ectopic expression of tissue-specific antigens in medullary thymic epithelial cells and enabling removal of self-reactive T-cells. AIRE expression has recently been detected in myeloid dendritic cells (DC), suggesting AIRE may have a significant role in peripheral tolerance. DC stimulation of T-cells is critical in determining the initiation or lack of an immune response, depending on the pattern of costimulation and cytokine production by DCs, defining immunogenic/inflammatory (inflDC) and tolerogenic (tolDC) DC. In AIRE-deficient patients and healthy controls, we validated the role of AIRE in the generation and function of monocyte-derived inflDC and tolDCs by determining mRNA and protein expression of AIRE and comparing activation markers (HLA-DR/DP/DQ,CD83,CD86,CD274(PDL-1),TLR-2), cytokine production (IL-12p70,IL-10,IL-6,TNF-α,IFN-γ) and T-cell stimulatory capacity (mixed lymphocyte reaction) of AIRE+ and AIRE- DCs. We show for the first time that: (1) tolDCs from healthy individuals express AIRE; (2) AIRE expression is not significantly higher in tolDC compared to inflDC; (3) tolDC can be generated from APECED patient monocytes and (4) tolDCs lacking AIRE retain the same phenotype and reduced T-cell stimulatory function. Our findings suggest that AIRE does not have a role in the induction and function of monocyte-derived tolerogenic DC in humans, but these findings do not exclude a role for AIRE in peripheral tolerance mediated by other cell types.

  15. The Comparative Performance of Batteries: The Lead-Acid and the Aluminum-Air Cells

    NASA Astrophysics Data System (ADS)

    Leroux, Xavier; Ottewill, Gerry A.; Walsh, Frank C.

    1996-08-01

    An experimental program designed to convey, to students aged 16 through undergraduate, the principles of battery electrochemistry through a comparative study of two different systems, the lead acid cell and aluminum air cell, is described.

  16. Aire Expression Is Inherent to Most Medullary Thymic Epithelial Cells during Their Differentiation Program.

    PubMed

    Kawano, Hiroshi; Nishijima, Hitoshi; Morimoto, Junko; Hirota, Fumiko; Morita, Ryoko; Mouri, Yasuhiro; Nishioka, Yasuhiko; Matsumoto, Mitsuru

    2015-12-01

    Aire in medullary thymic epithelial cells (mTECs) plays an important role in the establishment of self-tolerance. Because Aire(+) mTECs appear to be a limited subset, they may constitute a unique lineage(s) among mTECs. An alternative possibility is that all mTECs are committed to express Aire in principle, but Aire expression by individual mTECs is conditional. To investigate this issue, we established a novel Aire reporter strain in which endogenous Aire is replaced by the human AIRE-GFP-Flag tag (Aire/hAGF-knockin) fusion gene. The hAGF reporter protein was produced and retained very efficiently within mTECs as authentic Aire nuclear dot protein. Remarkably, snapshot analysis revealed that mTECs expressing hAGF accounted for >95% of mature mTECs, suggesting that Aire expression does not represent a particular mTEC lineage(s). We confirmed this by generating Aire/diphtheria toxin receptor-knockin mice in which long-term ablation of Aire(+) mTECs by diphtheria toxin treatment resulted in the loss of most mature mTECs beyond the proportion of those apparently expressing Aire. These results suggest that Aire expression is inherent to all mTECs but may occur at particular stage(s) and/or cellular states during their differentiation, thus accounting for the broad impact of Aire on the promiscuous gene expression of mTECs.

  17. Air quality analysis and related risk assessment for the Bonneville Power Administration's Resource Program Environmental Impact Statement

    SciTech Connect

    Glantz, C S; Burk, K W; Driver, C J; Liljegren, J C; Neitzel, D A; Schwartz, M N; Dana, M T; Laws, G L; Mahoney, L A; Rhoads, K

    1992-04-01

    The Bonneville Power Administration (BPA) is considering 12 different alternatives for acquiring energy resources over the next 20 years. Each of the alternatives utilizes a full range of energy resources (e.g., coal, cogeneration, conservation, and nuclear); however, individual alternatives place greater emphases on different types of power-producing resources and employ different timetables for implementing these resources. The environmental impacts that would result from the implementation of each alternative and the economic valuations of these impacts, will be an important consideration in the alternative selection process. In this report we discuss the methods used to estimate environmental impacts from the resource alternatives. We focus on pollutant emissions rates, ground-level air concentrations of basic criteria pollutants, the acidity of rain, particulate deposition, ozone concentrations, visibility attenuation, global warming, human health effects, agricultural and forest impacts, and wildlife impacts. For this study, pollutant emission rates are computed by processing BPA data on power production and associated pollutant emissions. The assessment of human health effects from ozone indicated little variation between the resource alternatives. Impacts on plants, crops, and wildlife populations from power plant emissions are projected to be minimal for all resource alternatives.

  18. Cathodes for lithium-air battery cells with acid electrolytes

    DOEpatents

    Xing, Yangchuan; Huang, Kan; Li, Yunfeng

    2016-07-19

    In various embodiments, the present disclosure provides a layered metal-air cathode for a metal-air battery. Generally, the layered metal-air cathode comprises an active catalyst layer, a transition layer bonded to the active catalyst layer, and a backing layer bonded to the transition layer such that the transition layer is disposed between the active catalyst layer and the backing layer.

  19. Diversity of TCRs on natural Foxp3+ T cells in mice lacking Aire expression.

    PubMed

    Daniely, Danielle; Kern, Joanna; Cebula, Anna; Ignatowicz, Leszek

    2010-06-15

    Medullary thymic epithelial cells expressing the Aire gene play a critical role in the induction of tolerance to tissue-specific Ags (TSAs). It was postulated that recognition of Aire-controlled TSAs by immature thymocytes results in the selection of natural CD4+Foxp3+ regulatory T cells (Tregs) and enriches this repertoire in self-reactive receptors, contributing to its vast diversity. In this study, we compared the TCRs on individual Tregs in Aire+ and Aire- mice expressing a miniature TCR repertoire (TCRmini) along with GFP driven by the Foxp3 promoter (Foxp3GFP). The Treg TCR repertoires in Aire+ and Aire- TCRminiFoxp3GFP mice were similar and more diverse than their repertoires on CD4+ Foxp3- thymocytes. Further, TCRs found on potentially self-reactive T cells, with an activated phenotype (CD4+Foxp3-CD62Llow) in Aire- TCRminiFoxp3GFP mice, appear distinct from TCRs found on Tregs in Aire+ TCRminiFoxp3GFP mice. Lastly, we found no evidence that TSAs presented by medullary thymic epithelial cells in Aire+TCRmini mice are often recognized as agonists by Treg-derived TCR hybridomas or CD4+CD25+ thymocytes, containing both natural Tregs and precursors. Thus, positive selection and self-reactivity of the global Treg repertoire are not controlled by Aire-dependent TSAs.

  20. Methods for advanced hepatocyte cell culture in microwells utilizing air bubbles.

    PubMed

    Goral, Vasiliy N; Au, Sam H; Faris, Ronald A; Yuen, Po Ki

    2015-02-21

    Flat, two-dimensional (2D) cell culture substrates are simple to use but offer little control over cell morphologies and behavior. In this article, we present a number of novel and unique methods for advanced cell culture in microwells utilizing air bubbles as a way to seed cells in order to provide substantial control over cellular microenvironments and organization to achieve specific cell-based applications. These cell culture methods enable controlled formation of stable air bubbles in the microwells that spontaneously formed when polar solvents such as cell culture media are loaded. The presence of air bubbles (air bubble masking) enables highly controllable cell patterning and organization of seeded cells as well as cell co-culture in microwells. In addition, these cell culture methods are simple to use and implement, yet versatile, and have the potential to provide a wide range of microenvironments to improve in vivo-like behavior for a number of cell types and applications. The air bubble masking technique can also be used to produce a micron thick layer of collagen film suspended on top of the microwells. These collagen film enclosed microwells could provide an easy way for high throughput drug screening and cytotoxicity assays as different drug compounds could be pre-loaded and dried in selected microwells and then released during cell culture.

  1. Promotion or suppression of experimental metastasis of B16 melanoma cells after oral administration of lapachol

    SciTech Connect

    Maeda, Masayo; Murakami, Manabu; Takegami, Tsutomu; Ota, Takahide

    2008-06-01

    Lapachol [2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthoquinone] is a vitamin K antagonist with antitumor activity. The effect of lapachol on the experimental metastasis of murine B16BL6 melanoma cells was examined. A single oral administration of a high toxic dose of lapachol (80-100 mg/kg) 6 h before iv injection of tumor cells drastically promoted metastasis. This promotion of metastasis was also observed in T-cell-deficient mice and NK-suppressed mice. In vitro treatment of B16BL6 cells with lapachol promoted metastasis only slightly, indicating that lapachol promotes metastasis primarily by affecting host factors other than T cells and NK cells. A single oral administration of warfarin, the most commonly used vitamin K antagonist, 6 h before iv injection of tumor cells also drastically promoted the metastasis of B16BL6 cells. The promotion of metastasis by lapachol and warfarin was almost completely suppressed by preadministration of vitamin K3, indicating that the promotion of metastasis by lapachol was derived from vitamin K antagonism. Six hours after oral administration of lapachol or warfarin, the protein C level was reduced maximally, without elongation of prothrombin time. These observations suggest that a high toxic dose of lapachol promotes metastasis by inducing a hypercoagulable state as a result of vitamin K-dependent pathway inhibition. On the other hand, serial oral administration of low non-toxic doses of lapachol (5-20 mg/kg) weakly but significantly suppressed metastasis by an unknown mechanism, suggesting the possible use of lapachol as an anti-metastatic agent.

  2. Study of DNA metabolism of lymph-node cells by direct lymphatic administration of tritiated thymidine.

    PubMed

    Kett, K; Nyárády, J; Zadravecz, G; Kellermayer, M; Lukács, L

    1978-01-01

    A method for studying DNA metabolism in lymph-node cells by injecting tritiated thymidine intralymphatically is described. The administration of [3H]thymidine through a lymph vessel enabled a high concentration to be attained with only a small quantity of the precursor in close proximity to the cells. The significance of the method is that it may also be used in studies of metabolic processes in human lymph-nodes.

  3. Air-stripping effects on cell growth with volatile substrates.

    PubMed

    Singh, N; Hill, G A

    1987-09-01

    The removal of substate molecules from aerobic microbial cultures is due to both consumption by microorganisms and stripping by the air stream. The air stripping component can be described by a constant parameter for low concentrations of volatile substrates. This air stripping parameter was found to have a value of 0.0033 h(-1) for phenol molecules in a typical fermentation situation. The determination and inclusion of this constant is important for modeling microbial growth. For Pseudomonas putida growing on phenol, it is shown that air stripping is responsible for all of the original decline in phenol concentration. Further, the kinetic inhibition constant is sensitive to both the value of the air stripping parameter and the value of the initial concentration of bacteria. The experimental data for Pseudomonas putida growing on phenol was fit by a non-linear, least squares technique to isolate the inhibition constant between 100 and 600 ppm.

  4. Intrapericardial Administration of Mesenchymal Stem Cells in a Large Animal Model: A Bio-Distribution Analysis

    PubMed Central

    Crisóstomo, Verónica; Báez, Claudia; Maestre, Juan; García-Lindo, Mónica; Usón, Alejandra; Álvarez, Verónica

    2015-01-01

    The appropriate administration route for cardiovascular cell therapy is essential to ensure the viability, proliferative potential, homing capacity and implantation of transferred cells. At the present, the intrapericardial administration of pharmacological agents is considered an efficient method for the treatment of cardiovascular diseases. However, only a few reports have addressed the question whether the intrapericardial delivery of Mesenchymal Stem Cells (MSCs) could be an optimal administration route. This work firstly aimed to analyze the pericardial fluid as a cell-delivery vehicle. Moreover, the in vivo biodistribution pattern of intrapericardially administered MSCs was evaluated in a clinically relevant large animal model. Our in vitro results firstly showed that, MSCs viability, proliferative behavior and phenotypic profile were unaffected by exposure to pericardial fluid. Secondly, in vivo cell tracking by magnetic resonance imaging, histological examination and Y-chromosome amplification clearly demonstrated the presence of MSCs in pericardium, ventricles (left and right) and atrium (left and right) when MSCs were administered into the pericardial space. In conclusion, here we demonstrate that pericardial fluid is a suitable vehicle for MSCs and intrapericardial route provides an optimal retention and implantation of MSCs. PMID:25816232

  5. Intrapericardial administration of mesenchymal stem cells in a large animal model: a bio-distribution analysis.

    PubMed

    Blázquez, Rebeca; Sánchez-Margallo, Francisco Miguel; Crisóstomo, Verónica; Báez, Claudia; Maestre, Juan; García-Lindo, Mónica; Usón, Alejandra; Álvarez, Verónica; Casado, Javier G

    2015-01-01

    The appropriate administration route for cardiovascular cell therapy is essential to ensure the viability, proliferative potential, homing capacity and implantation of transferred cells. At the present, the intrapericardial administration of pharmacological agents is considered an efficient method for the treatment of cardiovascular diseases. However, only a few reports have addressed the question whether the intrapericardial delivery of Mesenchymal Stem Cells (MSCs) could be an optimal administration route. This work firstly aimed to analyze the pericardial fluid as a cell-delivery vehicle. Moreover, the in vivo biodistribution pattern of intrapericardially administered MSCs was evaluated in a clinically relevant large animal model. Our in vitro results firstly showed that, MSCs viability, proliferative behavior and phenotypic profile were unaffected by exposure to pericardial fluid. Secondly, in vivo cell tracking by magnetic resonance imaging, histological examination and Y-chromosome amplification clearly demonstrated the presence of MSCs in pericardium, ventricles (left and right) and atrium (left and right) when MSCs were administered into the pericardial space. In conclusion, here we demonstrate that pericardial fluid is a suitable vehicle for MSCs and intrapericardial route provides an optimal retention and implantation of MSCs.

  6. Effects of anti-NKG2A antibody administration on leukemia and normal hematopoietic cells

    PubMed Central

    Ruggeri, Loredana; Urbani, Elena; André, Pascale; Mancusi, Antonella; Tosti, Antonella; Topini, Fabiana; Bléry, Mathieu; Animobono, Lucia; Romagné, François; Wagtmann, Nicolai; Velardi, Andrea

    2016-01-01

    Natural killer cells are key cells of the innate immune system. Natural killer cell receptor repertoires are diversified by a stochastic expression of killer-cell-immunoglobulin-like receptors and lectin-like receptors such as NKG2 receptors. All individuals harbor a subset of natural killer cells expressing NKG2A, the inhibitory checkpoint receptor for HLA-E. Most neoplastic and normal hematopoietic cells express HLA-E, the inhibitory ligand of NKG2A. A novel anti-human NKG2A antibody induced tumor cell death, suggesting that the antibody could be useful in the treatment of cancers expressing HLA-E. We found that immunodeficient mice, co-infused with human primary leukemia or Epstein-Barr virus cell lines and NKG2A+ natural killer cells, pre-treated with anti-human NKG2A, were rescued from disease progression. Human NKG2A+ natural killer cells reconstituted in immunodeficient mice after transplantation of human CD34+ cells. These natural killer cells are able to kill engrafted human primary leukemia or Epstein-Barr virus cell lines by lysis after intraperitoneal administration of anti-human NKG2A. Thus, this anti-NKG2A may exploit the anti-leukemic action of the wave of NKG2A+ natural killer cells recovering after hematopoietic stem cell transplants or adoptive therapy with natural killer cell infusions from matched or mismatched family donors after chemotherapy for acute leukemia, without the need to search for a natural killer cell alloreactive donor. PMID:26721894

  7. Aire controls mesenchymal stem cell-mediated suppression in chronic colitis.

    PubMed

    Parekkadan, Biju; Fletcher, Anne L; Li, Matthew; Tjota, Melissa Y; Bellemare-Pelletier, Angelique; Milwid, Jack M; Lee, Je-Wook; Yarmush, Martin L; Turley, Shannon J

    2012-01-01

    Mesenchymal stem cells (MSCs) are emerging as a promising immunotherapeutic, based largely on their overt suppression of T lymphocytes under inflammatory and autoimmune conditions. While paracrine cross-talk between MSCs and T cells has been well-studied, an intrinsic transcriptional switch that programs MSCs for immunomodulation has remained undefined. Here we show that bone marrow-derived MSCs require the transcriptional regulator Aire to suppress T cell-mediated pathogenesis in a mouse model of chronic colitis. Surprisingly, Aire did not control MSC suppression of T cell proliferation in vitro. Instead, Aire reduced T cell mitochondrial reductase by negatively regulating a proinflammatory cytokine, early T cell activation factor (Eta)-1. Neutralization of Eta-1 enabled Aire(-/-) MSCs to ameliorate colitis, reducing the number of infiltrating effector T cells in the colon, and normalizing T cell reductase levels. We propose that Aire represents an early molecular switch imposing a suppressive MSC phenotype via regulation of Eta-1. Monitoring Aire expression in MSCs may thus be a critical parameter for clinical use.

  8. DNA methylation signatures of the AIRE promoter in thymic epithelial cells, thymomas and normal tissues.

    PubMed

    Kont, Vivian; Murumägi, Astrid; Tykocinski, Lars-Oliver; Kinkel, Sarah A; Webster, Kylie E; Kisand, Kai; Tserel, Liina; Pihlap, Maire; Ströbel, Philipp; Scott, Hamish S; Marx, Alexander; Kyewski, Bruno; Peterson, Pärt

    2011-12-01

    Mutations in the AIRE gene cause autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), which is associated with autoimmunity towards several peripheral organs. The AIRE protein is almost exclusively expressed in medullary thymic epithelial cells (mTEC) and CpG methylation in the promoter of the AIRE gene has been suggested to control its tissue-specific expression pattern. We found that in human AIRE-positive medullary and AIRE-negative cortical epithelium, the AIRE promoter is hypomethylated, whereas in thymocytes, the promoter had high level of CpG methylation. Likewise, in mouse mTECs the AIRE promoter was uniformly hypomethylated. In the same vein, the AIRE promoter was hypomethylated in AIRE-negative thymic epithelial tumors (thymomas) and in several peripheral tissues. Our data are compatible with the notion that promoter hypomethylation is necessary but not sufficient for tissue-specific regulation of the AIRE gene. In contrast, a positive correlation between AIRE expression and histone H3 lysine 4 trimethylation, an active chromatin mark, was found in the AIRE promoter in human and mouse TECs.

  9. Changes in endothelial cell proliferation and vascular permeability after systemic lipopolysaccharide administration in the subfornical organ.

    PubMed

    Morita-Takemura, Shoko; Nakahara, Kazuki; Tatsumi, Kouko; Okuda, Hiroaki; Tanaka, Tatsuhide; Isonishi, Ayami; Wanaka, Akio

    2016-09-15

    The subfornical organ (SFO) has highly permeable fenestrated vasculature and is a key site for immune-to-brain communications. Recently, we showed the occurrence of continuous angiogenesis in the SFO. In the present study, we found that systemic administration of bacterial lipopolysaccharide (LPS) reduced the vascular permeability and endothelial cell proliferation. In LPS-administered mice, the SFO vasculature showed a significant decrease in the immunoreactivity of plasmalemma vesicle associated protein-1, a marker of endothelial fenestral diaphragms. These data suggest that vasculature undergoes structural change to decrease vascular permeability in response to systemic LPS administration. PMID:27609286

  10. The effect of injection using narrow‐bore needles on mammalian cells: administration and formulation considerations for cell therapies

    PubMed Central

    Amer, Mahetab H.; White, Lisa J.

    2015-01-01

    Abstract Objectives This study focuses on the effect of the injection administration process on a range of cell characteristics. Methods Effects of different ejection rates, needle sizes and cell suspension densities were assessed in terms of viability, membrane integrity, apoptosis and senescence of NIH 3T3 fibroblasts. For ratiometric measurements, a multiplex assay was used to verify cell viability, cytotoxicity and apoptosis independent of cell number. Co‐delivery with alginate hydrogels and viscosity‐modifying excipients was also assessed. Key findings Ejections at 150 μl/min resulted in the highest percentage of dose being delivered as viable cells among ejection rates tested. The difference in proportions of apoptotic cells became apparent 48 h after ejection, with proportions being higher in samples ejected at slower rates. Co‐delivery with alginate hydrogels demonstrated a protective action on the cell payload. Conclusions This study demonstrates the importance of careful consideration of administration protocols required for successful delivery of cell suspensions, according to their nature and cellular responses post‐ejection. PMID:25623928

  11. Combinatorial electrochemical cell array for high throughput screening of micro-fuel-cells and metal/air batteries

    NASA Astrophysics Data System (ADS)

    Jiang, Rongzhong

    2007-07-01

    An electrochemical cell array was designed that contains a common air electrode and 16 microanodes for high throughput screening of both fuel cells (based on polymer electrolyte membrane) and metal/air batteries (based on liquid electrolyte). Electrode materials can easily be coated on the anodes of the electrochemical cell array and screened by switching a graphite probe from one cell to the others. The electrochemical cell array was used to study direct methanol fuel cells (DMFCs), including high throughput screening of electrode catalysts and determination of optimum operating conditions. For screening of DMFCs, there is about 6% relative standard deviation (percentage of standard deviation versus mean value) for discharge current from 10to20mA/cm2. The electrochemical cell array was also used to study tin/air batteries. The effect of Cu content in the anode electrode on the discharge performance of the tin/air battery was investigated. The relative standard deviations for screening of metal/air battery (based on zinc/air) are 2.4%, 3.6%, and 5.1% for discharge current at 50, 100, and 150mA/cm2, respectively.

  12. Combinatorial electrochemical cell array for high throughput screening of micro-fuel-cells and metal/air batteries.

    PubMed

    Jiang, Rongzhong

    2007-07-01

    An electrochemical cell array was designed that contains a common air electrode and 16 microanodes for high throughput screening of both fuel cells (based on polymer electrolyte membrane) and metal/air batteries (based on liquid electrolyte). Electrode materials can easily be coated on the anodes of the electrochemical cell array and screened by switching a graphite probe from one cell to the others. The electrochemical cell array was used to study direct methanol fuel cells (DMFCs), including high throughput screening of electrode catalysts and determination of optimum operating conditions. For screening of DMFCs, there is about 6% relative standard deviation (percentage of standard deviation versus mean value) for discharge current from 10 to 20 mAcm(2). The electrochemical cell array was also used to study tin/air batteries. The effect of Cu content in the anode electrode on the discharge performance of the tin/air battery was investigated. The relative standard deviations for screening of metal/air battery (based on zinc/air) are 2.4%, 3.6%, and 5.1% for discharge current at 50, 100, and 150 mAcm(2), respectively. PMID:17672740

  13. Aire unleashes stalled RNA polymerase to induce ectopic gene expression in thymic epithelial cells.

    PubMed

    Giraud, Matthieu; Yoshida, Hideyuki; Abramson, Jakub; Rahl, Peter B; Young, Richard A; Mathis, Diane; Benoist, Christophe

    2012-01-10

    Aire is a transcriptional regulator that induces expression of peripheral tissue antigens (PTA) in thymic medullary epithelial cells (MECs), driving immunological self-tolerance in differentiating T cells. To elucidate its mechanistic pathways, we examined its transcriptional impact in MECs in vivo by microarray analysis with mRNA-spanning probes. This analysis revealed initiation of Aire-activated genes to be comparable in Aire-deficient and wild-type MECs, but with a block to elongation after 50-100 bp in the absence of Aire, suggesting activation by release of stalled polymerases by Aire. In contrast, patterns of activation by transcription factors such as Klf4 were consistent with regulation of initiation. Mapping of Aire and RNA polymerase-II (Pol-II) by ChIP and high-throughput sequencing (ChIP-seq) revealed that Aire bound all Pol-II-rich transcriptional start sites (TSS), irrespective of its eventual effect. However, the genes it preferentially activated were characterized by a relative surfeit of stalled polymerases at the TSS, which resolved once Aire was introduced into cells. Thus, transcript mapping and ChIP-seq data indicate that Aire activates ectopic transcription not through specific recognition of PTA gene promoters but by releasing stalled polymerases.

  14. Generation of regulatory dendritic cells and CD4+Foxp3+ T cells by probiotics administration suppresses immune disorders.

    PubMed

    Kwon, Ho-Keun; Lee, Choong-Gu; So, Jae-Seon; Chae, Chang-Suk; Hwang, Ji-Sun; Sahoo, Anupama; Nam, Jong Hee; Rhee, Joon Haeng; Hwang, Ki-Chul; Im, Sin-Hyeog

    2010-02-01

    The beneficial effects of probiotics have been described in many diseases, but the mechanism by which they modulate the immune system is poorly understood. In this study, we identified a mixture of probiotics that up-regulates CD4(+)Foxp3(+) regulatory T cells (Tregs). Administration of the probiotics mixture induced both T-cell and B-cell hyporesponsiveness and down-regulated T helper (Th) 1, Th2, and Th17 cytokines without apoptosis induction. It also induced generation of CD4(+)Foxp3(+) Tregs from the CD4(+)CD25(-) population and increased the suppressor activity of naturally occurring CD4(+)CD25(+) Tregs. Conversion of T cells into Foxp3(+) Tregs is directly mediated by regulatory dendritic cells (rDCs) that express high levels of IL-10, TGF-beta, COX-2, and indoleamine 2,3-dioxygenase. Administration of probiotics had therapeutical effects in experimental inflammatory bowel disease, atopic dermatitis, and rheumatoid arthritis. The therapeutical effect of the probiotics is associated with enrichment of CD4(+)Foxp3(+) Tregs in the inflamed regions. Collectively, the administration of probiotics that enhance the generation of rDCs and Tregs represents an applicable treatment of inflammatory immune disorders.

  15. TLR-2 IS INVOLVED IN AIRWAY EPITHELIAL CELL RESPONE TO AIR POLLUTION PARTICLES

    EPA Science Inventory

    Primary cultures of normal human airway epithelial cells (NHBE) respond to ambient air pollution particulate matter (PM) by increased production of the cytokine IL-8, and the induction of a number of oxidant stress response genes. Components of ambient air PM responsible for stim...

  16. Optimization of solar cells for air mass zero operation and a study of solar cells at high temperatures, phase 2

    NASA Technical Reports Server (NTRS)

    Hovel, H.; Woodall, J. M.

    1976-01-01

    Crystal growth procedures, fabrication techniques, and theoretical analysis were developed in order to make GaAlAs-GaAs solar cell structures which exhibit high performance at air mass 0 illumination and high temperature conditions.

  17. The Comparative Performance of Batteries: The Lead-Acid and the Aluminum-Air Cells.

    ERIC Educational Resources Information Center

    LeRoux, Xavier; And Others

    1996-01-01

    Describes a teaching program that shows how electrochemical principles can be conveyed by means of hands-on experiences of student-centered teaching experiments. Employs the readily available lead-acid cell and the simple aluminum-air cell. Discusses the batteries, equilibrium cell potential, performance comparison, current, electrode separation,…

  18. Cre-inducible human CD59 mediates rapid cell ablation after intermedilysin administration

    PubMed Central

    Feng, Dechun; Dai, Shen; Liu, Fengming; Ohtake, Yosuke; Zhou, Zhou; Wang, Hua; Zhang, Yonggang; Kearns, Alison; Peng, Xiao; Zhu, Faliang; Hayat, Umar; Li, Man; He, Yong; Xu, Mingjiang; Zhao, Chunling; Cheng, Min; Zhang, Lining; Wang, Hong; Yang, Xiaofeng; Ju, Cynthia; Bryda, Elizabeth C.; Gordon, Jennifer; Khalili, Kamel; Hu, Wenhui; Li, Shuxin; Qin, Xuebin

    2016-01-01

    Cell ablation is a powerful tool for studying cell lineage and/or function; however, current cell-ablation models have limitations. Intermedilysin (ILY), a cytolytic pore-forming toxin that is secreted by Streptococcus intermedius, lyses human cells exclusively by binding to the human complement regulator CD59 (hCD59), but does not react with CD59 from nonprimates. Here, we took advantage of this feature of ILY and developed a model of conditional and targeted cell ablation by generating floxed STOP-CD59 knockin mice (ihCD59), in which expression of human CD59 only occurs after Cre-mediated recombination. The administration of ILY to ihCD59+ mice crossed with various Cre-driver lines resulted in the rapid and specific ablation of immune, epithelial, or neural cells without off-target effects. ILY had a large pharmacological window, which allowed us to perform dose-dependent studies. Finally, the ILY/ihCD59-mediated cell-ablation method was tested in several disease models to study immune cell functionalities, hepatocyte and/or biliary epithelial damage and regeneration, and neural cell damage. Together, the results of this study demonstrate the utility of the ihCD59 mouse model for studying the effects of cell ablation in specific organ systems in a variety of developmental and disease states. PMID:27159394

  19. The susceptibility of Aire(-/-) mice to experimental myasthenia gravis involves alterations in regulatory T cells.

    PubMed

    Aricha, Revital; Feferman, Tali; Scott, Hamish S; Souroujon, Miriam C; Berrih-Aknin, Sonia; Fuchs, Sara

    2011-02-01

    The autoimmune regulator (Aire) is involved in the prevention of autoimmunity by promoting thymic expression of tissue restricted antigens which leads to elimination of self-reactive T cells. We found that Aire knockout (KO) mice as well as mouse strains that are susceptible to experimental autoimmune myasthenia gravis (EAMG) have lower thymic expression of acetylcholine receptor (AChR- the main autoantigen in MG), compared to wild type (WT) mice and EAMG-resistant mouse strains, respectively. We demonstrated that Aire KO mice have a significant and reproducible lower frequency of CD4+Foxp3+ cells and a higher expression of Th17 markers in their thymus, compared to wild type (WT) mice. These findings led us to expect that Aire KO mice would display increased susceptibility to EAMG. Surprisingly, when EAMG was induced in young (2 month-old) mice, EAMG was milder in Aire KO than in WT mice for several weeks until the age of about 5 months. However, when EAMG was induced in relatively aged (6 month-old) mice, Aire KO mice presented higher disease severity than WT controls. This age-related change in susceptibility to EAMG correlated with an elevated proportion of Treg cells in the spleens of young but not old KO, compared to WT mice, suggesting a role for peripheral Treg cells in the course of disease. Our observations point to a possible link between Aire and Treg cells and suggest an involvement for both in the pathogenesis of myasthenia.

  20. A 26-Week Toxicity Assessment of AIR001 (Sodium Nitrite) by Inhalation Exposure in Rats and by Intravenous Administration in Dogs.

    PubMed

    Tepper, Jeffrey; Ochoa, Ricardo; Rix, Peter; Elliott, Gary; Hoglen, Niel; Poulin, Dominic; Parsley, Ed; Masamune, Hiroko

    2014-05-01

    Historically, nitrogen oxides (NOx) in food, drinking water, as well as in the atmosphere have been believed to be associated with adverse health consequences. More recently, NOx have been implicated in normal homeostatic regulation, and exogenous administration has been associated with health benefits. One such potential health benefit is the prospect that inhaled nitrite will lower pulmonary blood pressure (BP) in patients with pulmonary arterial hypertension (PAH), a disease with poor prognosis due to the lack of effective treatment. To characterize potential chronic toxicity associated with inhaled AIR001 (sodium nitrite) for use in the treatment of PAH, 26-week exposures to AIR001 were carried out by inhalation administration in rats and by intravenous infusion in dogs. The studies revealed that methemoglobinemia was the primary adverse effect in both species. Methemoglobin levels less than 40% were well tolerated in both species, while levels greater than 50% methemoglobin caused death in some rats. Additionally, a decrease in systemic BP was also observed with inhaled AIR001 exposure in dogs. These acute secondary and exaggerated pharmacological effects occurred daily throughout the 26-week treatment period. Chronic exposure did not alter the magnitude of either methemoglobinemia or hypotension or result in additional toxicity or compensatory responses. Based on the exposure levels that produced these pharmacodynamic responses in animals, relative to those measured in early clinical studies, it appears that an adequate margin of safety exists to support the continued clinical development of inhaled AIR001.

  1. Air feed tube support system for a solid oxide fuel cell generator

    DOEpatents

    Doshi, Vinod B.; Ruka, Roswell J.; Hager, Charles A.

    2002-01-01

    A solid oxide fuel cell generator (12), containing tubular fuel cells (36) with interior air electrodes (18), where a supporting member (82) containing a plurality of holes (26) supports oxidant feed tubes (51), which pass from an oxidant plenum (52") into the center of the fuel cells, through the holes (26) in the supporting member (82), where a compliant gasket (86) around the top of the oxidant feed tubes and on top (28) of the supporting member (82) helps support the oxidant feed tubes and center them within the fuel cells, and loosen the tolerance for centering the air feed tubes.

  2. Bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in five painted storks.

    PubMed

    Weber, Martha A; Terrell, Scott P; Neiffer, Donald L; Miller, Michele A; Mangold, Barbara J

    2002-08-01

    Five painted storks were treated with fenbendazole for 5 days for internal parasitism. Four birds died following treatment. Profound heteropenia was a consistent finding in all samples evaluated; additionally, the 1 surviving bird had progressive anemia. Consistent necropsy findings in the 4 birds that died were small intestinal crypt cell necrosis and severe bone marrow depletion and necrosis. Fenbendazole has been associated with bone marrow hypoplasia and enteric damage in mammals and other species of birds. The dosages of fenbendazole used in birds are often substantially higher than those recommended for mammals, which may contribute to bone marrow hypoplasia and intestinal crypt cell necrosis associated with fenbendazole administration in birds.

  3. Reporter gene expression in dendritic cells after gene gun administration of plasmid DNA.

    PubMed

    Watkins, Craig; Hopkins, John; Harkiss, Gordon

    2005-07-21

    Dendritic cells (DC) play an integral role in plasmid DNA vaccination. However, the interaction between plasmid DNA and DC in vivo is incompletely understood. In this report, we utilise the sheep pseudoafferent cannulation model to examine the interaction between plasmid DNA encoding enhanced green fluorescent protein (pEGFP) and afferent lymph DC (ALDC) following gene gun administration. The results show that peaks of fluorescent ALDC tended to appear around days 1-4 and 9-13, then erratically thereafter for up to 2 months. Phenotypic analysis showed that EGFP+ ALDC expressed MHC class II, WC6, CD1b, and SIRPalpha markers. Plasmid, detected by PCR, was found in lymph cells and cell-free plasma on a daily basis, and was present variably for up to 2 months. Plasmid was also detected in purified CD1b+ ALDC, but the presence of plasmid did not correlate with EGFP expression by ALDC. Free EGFP in afferent lymph plasma was detectable by luminometry only after three administrations of the plasmid. The results show that gene gun administered pEGFP persisted for extended periods after a single administration, leeching out of skin on a daily basis. The plasmid was associated with both the cellular and fluid components of afferent lymph. EGFP protein appeared in afferent lymph in a pulsatile manner, but associated only with ALDC.

  4. Influence of Lithium Salts on the Discharge Chemistry of Li-Air Cells.

    PubMed

    Veith, Gabriel M; Nanda, Jagjit; Delmau, Laetitia H; Dudney, Nancy J

    2012-05-17

    In this work, we show that the use of a high boiling point ether solvent (tetraglyme) promotes the formation of Li2O2 in a lithium-air cell. However, another major constituent in the discharge product of a Li-air cell contains halides from the lithium salts and C-O from the tetraglyme used as the solvent. This information is critical to the development of Li-air electrolytes, which are stable and promote the formation of the desired Li2O2 products. PMID:26286765

  5. Influence of lithium salts on the discharge chemistry of Li-air cells

    SciTech Connect

    Veith, Gabriel M; Nanda, Jagjit; Delmau, Laetitia Helene; Dudney, Nancy J

    2012-01-01

    In this work we show that the use of a high boiling point ether solvent (tetraglyme) promotes the formation of Li2O2 in a lithium-air cell. In addition, another major constituent in the discharge product of a Li-air cell contains halides, from the lithium salt, and the tetraglyme used as the solvent. This information is critical to the development of Li-air electrolytes which are stable and promote the formation of the desired Li2O2 products.

  6. Central Administration of Galanin Receptor 1 Agonist Boosted Insulin Sensitivity in Adipose Cells of Diabetic Rats

    PubMed Central

    Zhang, Zhenwen; Fang, Penghua; He, Biao; Guo, Lili; Runesson, Johan; Langel, Ülo; Shi, Mingyi; Zhu, Yan; Bo, Ping

    2016-01-01

    Our previous studies testified the beneficial effect of central galanin on insulin sensitivity of type 2 diabetic rats. The aim of the study was further to investigate whether central M617, a galanin receptor 1 agonist, can benefit insulin sensitivity. The effects of intracerebroventricular administration of M617 on insulin sensitivity and insulin signaling were evaluated in adipose tissues of type 2 diabetic rats. The results showed that central injection of M617 significantly increased plasma adiponectin contents, glucose infusion rates in hyperinsulinemic-euglycemic clamp tests, GLUT4 mRNA expression levels, GLUT4 contents in plasma membranes, and total cell membranes of the adipose cells but reduced the plasma C-reactive protein concentration in nondiabetic and diabetic rats. The ratios of GLUT4 contents were higher in plasma membranes to total cell membranes in both nondiabetic and diabetic M617 groups than each control. In addition, the central administration of M617 enhanced the ratios of pAkt/Akt and pAS160/AS160, but not phosphorylative cAMP response element-binding protein (pCREB)/CREB in the adipose cells of nondiabetic and diabetic rats. These results suggest that excitation of central galanin receptor 1 facilitates insulin sensitivity via activation of the Akt/AS160 signaling pathway in the fat cells of type 2 diabetic rats. PMID:27127795

  7. Detonation cell size measurements and predictions in hydrogen-air-steam mixtures at elevated temperatures

    SciTech Connect

    Ciccarelli, G.; Ginsberg, T.; Boccio, J.; Economos, C.

    1994-01-01

    The present research reports on the effect of initial mixture temperature on the experimentally measured detonation cell size for hydrogen-air-steam mixtures. Experimental and theoretical research related to combustion phenomena in hydrogen-air-steam mixtures has been ongoing for many years. However, detonation cell size data currently exists or hydrogen-air-steam mixtures up to a temperature of only 400K. Sever accident scenarios have been identified for light water reactors (LWRs) where hydrogen-air mixture temperatures in excess of 400K could be generated within containment. The experiments in this report focus on extending the cell size data base for initial mixture temperatures in excess of 400K. The experiments were carried out in a 10-cm inner-diameter, 6.1-m long heated detonation tube with a maximum operating temperature of 700K and spatial temperature uniformity of {plus_minus}14K. Detonation cell size measurements provide clear evidence that the effect of hydrogen-air initial gas mixture temperature, in the range 300K--650K, is to decrease cell size and, hence, to increase the sensitivity of the mixture to undergo detonations. The effect of steam content, at any given temperature, is to increase the cell size and, thereby, to decrease the sensitivity of stoichiometric hydrogen-air mixtures. The hydrogen-air detonability limits for the 10-cm inside-diameter test vessel, based upon the onset of single-head spin, decreased from 15 percent by hydrogen at 300K down to about 9 percent hydrogen at 650K. The one-dimensional ZND model does a very good job at predicting the overall trends in the cell size data over the range of hydrogen-air-steam mixture compositions and temperature studied in the experiments.

  8. Intravenous Administration of Human ES-derived Neural Precursor Cells Attenuates Cuprizone-induced CNS Demyelination

    PubMed Central

    Crocker, Stephen J.; Bajpai, Ruchi; Moore, Craig S.; Frausto, Ricardo F.; Brown, Graham D.; Pagarigan, Roberto R.; Whitton, J. Lindsay; Terskikh, Alexey V.

    2011-01-01

    Aims Previous studies have demonstrated the therapeutic potential for human embryonic stem cell-derived neural precursor cells (hES-NPCs) in autoimmune and genetic animal models of demyelinating diseases. Herein, we tested whether intravenous (i.v) administration of hES-NPCs would impact central nervous system (CNS) demyelination in a cuprizone model of demyelination. Methods C57Bl/6 mice were fed cuprizone (0.2%) for two weeks and then separated into two groups that either received an i.v. injection of hES-NPCs or i.v. administration of media without these cells. After an additional two weeks of dietary cuprizone treatment, CNS tissues were analyzed for detection of transplanted cells and differences in myelination in the region of the corpus callosum (CC). Results Cuprizone-induced demyelination in the CC was significantly reduced in mice treated with hES-NPCs compared with cuprizone-treated controls that did not receive stem cells. hES-NPCs were identified within the brain tissues of treated mice and revealed migration of transplanted cells into the CNS. A limited number of human cells were found to express the mature oligodendrocyte marker, O1, or the astrocyte marker, GFAP. Reduced apoptosis and attenuated microglial and astrocytic responses were also observed in the CC of hES-NPC-treated mice. Conclusions These findings indicated that systemically-administered hES-NPCs migrated from circulation into a demyelinated lesion within the CNS and effectively reduced demyelination. Observed reductions in astrocyte and microglial responses, and (c) the benefit of hES-NPC treatment in this model of myelin injury was not obviously accountable to tissue replacement by exogenously administered cells. PMID:21276029

  9. Fluidic and air-stable supported lipid bilayer and cell-mimicking microarrays.

    PubMed

    Deng, Yang; Wang, Yini; Holtz, Bryan; Li, Jingyi; Traaseth, Nathan; Veglia, Gianluigi; Stottrup, Benjamin J; Elde, Robert; Pei, Duanqing; Guo, Athena; Zhu, X-Y

    2008-05-14

    As drug delivery, therapy, and medical imaging are becoming increasingly cell-specific, there is a critical need for high fidelity and high-throughput screening methods for cell surface interactions. Cell membrane-mimicking surfaces, i.e., supported lipid bilayers (SLBs), are currently not sufficiently robust to meet this need. Here we describe a method of forming fluidic and air-stable SLBs through tethered and dispersed cholesterol groups incorporated into the bottom leaflet. Achieving air stability allows us to easily fabricate SLB microarrays from direct robotic spotting of vesicle solutions. We demonstrate their application as cell membrane-mimicking microarrays by reconstituting peripheral as well as integral membrane components that can be recognized by their respective targets. These demonstrations establish the viability of the fluidic and air-stable SLB platform for generating content microarrays in high throughput studies, e.g., the screening of drugs and nanomedicine targeting cell surface receptors.

  10. Atmospheric-pressure air microplasma jets in aqueous media for the inactivation of Pseudomonas fluorescens cells

    SciTech Connect

    Zhang, Xianhui; Yang, Si-ze; Liu, Dongping; Song, Ying; Sun, Yue

    2013-05-15

    The hollow fiber-based cold air microplasma jet array running at atmospheric pressure has been designed to inactivate Pseudomonas fluorescens (P. fluorescens) cells in vitro in aqueous media. The influences of electrode configurations, air flow rate, and applied voltage on the discharge characteristics of the single microplasma jet operating in aqueous media are presented, and the bactericidal efficiency of the hollow fibers-based and large-volume microplasma jet array is reported. Optical emission spectroscopy is utilized to identify excited species during the antibacterial testing of plasma in solutions. These well-aligned and rather stable air microplasma jets containing a variety of short-lived species, such as OH and O radicals and charged particles, are in direct contact with aqueous media and are very effective in killing P. fluorescens cells in aqueous media. This design shows its potential application for atmospheric pressure air plasma inactivation of bacteria cells in aqueous media.

  11. Gentamicin is primarily localized in vestibular type I hair cells after intratympanic administration.

    PubMed

    Lyford-Pike, Sofia; Vogelheim, Casey; Chu, Eugene; Della Santina, Charles C; Carey, John P

    2007-12-01

    Intratympanic (IT) gentamicin injections are effective in the control of episodic vertigo due to Ménière's disease. Histological studies in animals have found that the loss of type I vestibular hair cells far exceeds that of type II cells after IT gentamicin treatment. The objective of this study was to determine whether this selective toxicity for type I hair cells might be due to selective concentration of the drug by these cells. Gentamicin was localized within the vestibular epithelium by both direct and indirect methods. Gentamicin conjugated to Texas Red(R) was used as a direct tracer, and anti-gentamicin antibody provided an indirect means of localization. Conjugated or unconjugated gentamicin was injected into the left tympanic space of chinchillas. The animals were killed and fixed 1 or 3 weeks post-treatment. Confocal fluorescence microscopy was used to determine the localization of gentamicin in semicircular canal cristae. Results from the animals killed within 1 week of administration showed that numerous type I hair cells still remained throughout the epithelium. The mean intensity in grayscale units (0-255) of anti-gentamicin labeling for type I hair cells was 28.14 (95% CI 24.60-31.69), for type II hair cells was 17.09 (14.99-19.20), and for support cells was 5.35 (5.34-5.46; p < 0.001, ANOVA). Anti-gentamicin antibody labeling appeared in the majority of type I hair cells throughout their cytoplasm, but with greater intensity at the apex (p < 0.001). Intensity of fluorescence with Texas-Red conjugated gentamicin was 25.38 (22.83-27.94) in type I hair cells, 15.60 (14.73-16.48) in type II cells, and 12.62 (12.06-13.17) in support cells (p < 0.001, ANOVA). These results suggest that type I hair cells are more susceptible to gentamicin because they more avidly take up or retain the drug in the early period after administration. PMID:17899270

  12. Air pollution effects on the guard cells of the injury resistant leaf of Laurus nobilis L

    SciTech Connect

    Christodoulakis, N.S. )

    1993-09-01

    The need for cleaner air has led to detailed investigations not only on the sources and types of air pollutants but also on the effect that these compounds have on various life forms. The plants are the first [open quotes]victims[close quotes] of the air pollutants. Extensive literature exists on the structural damages and functional problems that plants suffer after being exposed to air pollutants. Many investigators prefer to deal with damages, caused to various organs, in plants growing in non polluted environments, after being fumigated with certain air pollutants. Others investigate the problems in plants growing in polluted areas thus being subject to long-term exposure to air pollutants. Generally it seems that primary producers suffer injuries, most of the time serious, that finally lead to the suppression of photosynthesis with all the undesirable consequences that this situation has for the ecosystem. Unfortunately Athens is not only the most polluted city in Greece but also an example to be avoided among the most polluted cities in the world. Serious problems occur in plants living in this environment. One exception is Laurus nobilis, introduced as an injury resistant species. These researchers studied the plant cells and the structure of their organelles, focusing on the guard cells of the leaves. They occur on the underside of leaves and they are directly affected by polluted air. Studies show that the air pollution injury resistance of Laurus is genetic. 25 refs., 21 figs

  13. Functional Domains of Autoimmune Regulator (AIRE) Modulate INS-VNTR Transcription in Human Thymic Epithelial Cells.

    PubMed

    Sparks, Avis E; Chen, Chiachen; Breslin, Mary B; Lan, Michael S

    2016-05-20

    INS-VNTR (insulin-variable number of tandem repeats) and AIRE (autoimmune regulator) have been associated with the modulation of insulin gene expression in thymus, which is essential to induce either insulin tolerance or the development of insulin autoimmunity and type 1 diabetes. We sought to analyze whether each functional domain of AIRE is critical for the activation of INS-VNTR in human thymic epithelial cells. Twelve missense or nonsense mutations in AIRE and two chimeric AIRE constructs were generated. A luciferase reporter assay and a pulldown assay using biotinylated INS-class I VNTR probe were performed to examine the transactivation and binding activities of WT, mutant, and chimeric AIREs on the INS-VNTR promoter. Confocal microscopy analysis was performed for WT or mutant AIRE cellular localization. We found that all of the AIRE mutations resulted in loss of transcriptional activation of INS-VNTR except mutant P252L. Using WT/mutant AIRE heterozygous forms to modulate the INS-VNTR target revealed five mutations (R257X, G228W, C311fsX376, L397fsX478, and R433fsX502) that functioned in a dominant negative fashion. The LXXLL-3 motif is identified for the first time to be essential for DNA binding to INS-VNTR, whereas the intact PHD1, PHD2, LXXLL-3, and LXXLL-4 motifs were important for successful transcriptional activation. AIRE nuclear localization in the human thymic epithelial cell line was disrupted by mutations in the homogenously staining region domain and the R257X mutation in the PHD1 domain. This study supports the notion that AIRE mutation could specifically affect human insulin gene expression in thymic epithelial cells through INS-VNTR and subsequently induce either insulin tolerance or autoimmunity. PMID:27048654

  14. Functional Domains of Autoimmune Regulator (AIRE) Modulate INS-VNTR Transcription in Human Thymic Epithelial Cells.

    PubMed

    Sparks, Avis E; Chen, Chiachen; Breslin, Mary B; Lan, Michael S

    2016-05-20

    INS-VNTR (insulin-variable number of tandem repeats) and AIRE (autoimmune regulator) have been associated with the modulation of insulin gene expression in thymus, which is essential to induce either insulin tolerance or the development of insulin autoimmunity and type 1 diabetes. We sought to analyze whether each functional domain of AIRE is critical for the activation of INS-VNTR in human thymic epithelial cells. Twelve missense or nonsense mutations in AIRE and two chimeric AIRE constructs were generated. A luciferase reporter assay and a pulldown assay using biotinylated INS-class I VNTR probe were performed to examine the transactivation and binding activities of WT, mutant, and chimeric AIREs on the INS-VNTR promoter. Confocal microscopy analysis was performed for WT or mutant AIRE cellular localization. We found that all of the AIRE mutations resulted in loss of transcriptional activation of INS-VNTR except mutant P252L. Using WT/mutant AIRE heterozygous forms to modulate the INS-VNTR target revealed five mutations (R257X, G228W, C311fsX376, L397fsX478, and R433fsX502) that functioned in a dominant negative fashion. The LXXLL-3 motif is identified for the first time to be essential for DNA binding to INS-VNTR, whereas the intact PHD1, PHD2, LXXLL-3, and LXXLL-4 motifs were important for successful transcriptional activation. AIRE nuclear localization in the human thymic epithelial cell line was disrupted by mutations in the homogenously staining region domain and the R257X mutation in the PHD1 domain. This study supports the notion that AIRE mutation could specifically affect human insulin gene expression in thymic epithelial cells through INS-VNTR and subsequently induce either insulin tolerance or autoimmunity.

  15. Air sparging for prevention of antibody disulfide bond reduction in harvested CHO cell culture fluid.

    PubMed

    Mun, Melissa; Khoo, Stefanie; Do Minh, Aline; Dvornicky, James; Trexler-Schmidt, Melody; Kao, Yung-Hsiang; Laird, Michael W

    2015-04-01

    During the scale-up of several Chinese Hamster Ovary (CHO) cell monoclonal antibody production processes, significant reduction of the antibody interchain disulfide bonds was observed. The reduction was correlated with excessive mechanical cell shear during the harvest operations. These antibody reduction events resulted in failed product specifications and the subsequent loss of the drug substance batches. Several methods were recently developed to prevent antibody reduction, including modifying the cell culture media, using pre- and post-harvest chemical additions to the cell culture fluid (CCF), lowering the pH, and air sparging of the harvested CCF (HCCF). The work described in this paper further explores the option of HCCF air sparging for preventing antibody reduction. Here, a small-scale model was developed using a 3-L bioreactor to mimic the conditions of a manufacturing-scale harvest vessel and was subsequently employed to evaluate several air sparging strategies. In addition, these studies enabled further understanding of the relationships between cell lysis levels, oxygen consumption, and antibody reduction. Finally, the effectiveness of air sparging for several CHO cell lines and the potential impact on product quality were assessed to demonstrate that air sparging is an effective method in preventing antibody reduction.

  16. Retrieval of air temperatures from crowd-sourced battery temperatures of cell phones

    NASA Astrophysics Data System (ADS)

    Overeem, Aart; Robinson, James; Leijnse, Hidde; Uijlenhoet, Remko; Steeneveld, Gert-Jan; Horn, Berthold K. P.

    2013-04-01

    Accurate air temperature observations are important for urban meteorology, for example to study the urban heat island and adverse effects of high temperatures on human health. The number of available temperature observations is often relatively limited. A new development is presented to derive temperature information for the urban canopy from an alternative source: cell phones. Battery temperature data were collected by users of an Android application for cell phones (opensignal.com). The application automatically sends battery temperature data to a server for storage. In this study, battery temperatures are averaged in space and time to obtain daily averaged battery temperatures for each city separately. A regression model, which can be related to a physical model, is employed to retrieve daily air temperatures from battery temperatures. The model is calibrated with observed air temperatures from a meteorological station of an airport located in or near the city. Time series of air temperatures are obtained for each city for a period of several months, where 50% of the data is for independent verification. Results are presented for Buenos Aires, London, Los Angeles, Paris, Mexico City, Moscow, Rome, and Sao Paulo. The evolution of the retrieved air temperatures often correspond well with the observed ones. The mean absolute error of daily air temperatures is less than 2 degrees Celsius, and the bias is within 1 degree Celsius. This shows that monitoring air temperatures employing an Android application holds great promise. Since 75% of the world's population has a cell phone, 20% of the land surface of the earth has cellular telephone coverage, and 500 million devices use the Android operating system, there is a huge potential for measuring air temperatures employing cell phones. This could eventually lead to real-time world-wide temperature maps.

  17. Metal-air cell comprising an electrolyte with a room temperature ionic liquid and hygroscopic additive

    SciTech Connect

    Friesen, Cody A.; Krishnan, Ramkumar; Tang, Toni; Wolfe, Derek

    2014-08-19

    An electrochemical cell comprising an electrolyte comprising water and a hydrophobic ionic liquid comprising positive ions and negative ions. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. A hydrophilic or hygroscopic additive modulates the hydrophobicity of the ionic liquid to maintain a concentration of the water in the electrolyte is between 0.001 mol % and 25 mol %.

  18. A review of Air Force high efficiency cascaded multiple bandgap solar cell research and development

    NASA Technical Reports Server (NTRS)

    Rahilly, W. P.

    1979-01-01

    At the time of their conception, the cell stack systems to be discussed represent the best semiconductor materials combinations to achieve Air Force program goals. These systems are investigated thoroughly and the most promising systems, from the standpoint of high efficiency, are taken for further development with large area emphasized (at least 4 sq cm). The emphasis in the Air Force cascaded cell program is placed on eventual nonconcentrator application. This use of the final cell design considerably relieves the low resistance requirements for the tunnel junction. In a high concentration application the voltage drop across the tunnel junction can be a very serious problem.

  19. Air Force Ni-Cd cell qualification program update

    NASA Technical Reports Server (NTRS)

    Hall, Steve; Brown, Harry; Collins, G.; Hwang, W.; Bui, Q.

    1993-01-01

    The generic qualification of aerospace nickel-cadmium cells is discussed. The test program includes the following: all available manufacturers, all available designs, cells from the previous program, and high and low orbit life cycling. It is the purpose of this program to characterize the beginning of life performance.

  20. Cell kinetics in mouse lung following administration of carcinogens and butylated hydroxytoluene

    SciTech Connect

    Witschi, H.P.; Morse, C.C.

    1985-01-01

    A series of experiments is described which was designed to test the hypothesis that, in mouse lung, enhancement of tumor development could occur independently of overall alveolar cell hyperplasia. Male A/J mice were given 1000 mg/kg of urethane or 10 mg/kg of 3-methylcholanthrene (MCA). Alveolar cells were labeled through continuous infusion of (TH)thymidine for 6 weeks after administration of the carcinogen. Urethane produced a significant hyperplasia of the type II alveolar cell population, whereas MCA had no such effect. Five repeated injections of 300 mg/kg of butylated hydroxytoluene (BHT), a procedure known to enhance lung tumor development, produced cell hyperplasia only during the first 2 weeks; later the mice became resistant to the action of BHT. In animals treated with piperonyl butoxide prior to BHT, cell proliferation was abolished. BHT still had a small but significant enhancing effect on tumor development. However, this effect was dwarfed by the observation that piperonyl butoxide alone greatly inhibited tumor development. The data do not allow exclusion of alveolar cell hyperplasia as a mechanism in BHT-mediated enhancement of mouse lung tumor development. 19 references, 4 figures, 3 tables.

  1. In vivo administration of dental epithelial stem cells at the apical end of the mouse incisor

    PubMed Central

    Orsini, Giovanna; Jimenez-Rojo, Lucia; Natsiou, Despoina; Putignano, Angelo; Mitsiadis, Thimios A.

    2015-01-01

    Cell-based tissue regeneration is an attractive approach that complements traditional surgical techniques for replacement of injured and lost tissues. The continuously growing rodent incisor provides an excellent model system for investigating cellular and molecular mechanisms that underlie tooth renewal and regeneration. An active population of dental epithelial progenitor/stem cells located at the posterior part of the incisor, commonly called cervical loop area, ensures the continuous supply of cells that are responsible for the secretion of enamel matrix. To explore the potential of these epithelial cells in therapeutic approaches dealing with enamel defects, we have developed a new method for their in vivo administration in the posterior part of the incisor. Here, we provide the step-by-step protocol for the isolation of dental epithelial stem cells and their delivery at targeted areas of the jaw. This simple and yet powerful protocol, consisting in drilling a hole in the mandibular bone, in close proximity to the cervical loop area of the incisor, followed up by injection of stem cells, is feasible, reliable, and effective. This in vivo approach opens new horizons and possibilities for cellular therapies involving pathological and injured dental tissues. PMID:25914649

  2. Preterm white matter brain injury is prevented by early administration of umbilical cord blood cells.

    PubMed

    Li, Jingang; Yawno, Tamara; Sutherland, Amy; Loose, Jan; Nitsos, Ilias; Bischof, Robert; Castillo-Melendez, Margie; McDonald, Courtney A; Wong, Flora Y; Jenkin, Graham; Miller, Suzanne L

    2016-09-01

    Infants born very preterm are at high risk for neurological deficits including cerebral palsy. In this study we assessed the neuroprotective effects of umbilical cord blood cells (UCBCs) and optimal administration timing in a fetal sheep model of preterm brain injury. 50 million allogeneic UCBCs were intravenously administered to fetal sheep (0.7 gestation) at 12h or 5d after acute hypoxia-ischemia (HI) induced by umbilical cord occlusion. The fetal brains were collected at 10d after HI. HI (n=7) was associated with reduced number of oligodendrocytes (Olig2+) and myelin density (CNPase+), and increased density of activated microglia (Iba-1+) in cerebral white matter compared to control fetuses (P<0.05). UCBCs administered at 12h, but not 5d after HI, significantly protected white matter structures and suppressed cerebral inflammation. Activated microglial density showed a correlation with decreasing oligodendrocyte number (P<0.001). HI caused cell death (TUNEL+) in the internal capsule and cell proliferation (Ki-67+) in the subventricular zone compared to control (P<0.05), while UCBCs at 12h or 5d ameliorated these effects. Additionally, UCBCs at 12h induced a significant systemic increase in interleukin-10 at 10d, and reduced oxidative stress (malondialdehyde) following HI (P<0.05). UCBC administration at 12h after HI reduces preterm white matter injury, via anti-inflammatory and antioxidant actions. PMID:27317990

  3. Three-wheel air turbocompressor for PEM fuel cell systems

    DOEpatents

    Rehg, Tim; Gee, Mark; Emerson, Terence P.; Ferrall, Joe; Sokolov, Pavel

    2003-08-19

    A fuel cell system comprises a compressor and a fuel processor downstream of the compressor. A fuel cell stack is in communication with the fuel processor and compressor. A combustor is downstream of the fuel cell stack. First and second turbines are downstream of the fuel processor and in parallel flow communication with one another. A distribution valve is in communication with the first and second turbines. The first and second turbines are mechanically engaged to the compressor. A bypass valve is intermediate the compressor and the second turbine, with the bypass valve enabling a compressed gas from the compressor to bypass the fuel processor.

  4. Air stable organic-inorganic nanoparticles hybrid solar cells

    DOEpatents

    Qian, Lei; Yang, Jihua; Xue, Jiangeng; Holloway, Paul H.

    2015-09-29

    A solar cell includes a low work function cathode, an active layer of an organic-inorganic nanoparticle composite, a ZnO nanoparticle layer situated between and physically contacting the cathode and active layers; and a transparent high work function anode that is a bilayer electrode. The inclusion of the ZnO nanoparticle layer results in a solar cell displaying a conversion efficiency increase and reduces the device degradation rate. Embodiments of the invention are directed to novel ZnO nanoparticles that are advantageous for use as the ZnO nanoparticle layers of the novel solar cells and a method to prepare the ZnO nanoparticles.

  5. Planar solid oxide fuel cell with staged indirect-internal air and fuel preheating and reformation

    DOEpatents

    Geisbrecht, Rodney A; Williams, Mark C

    2003-10-21

    A solid oxide fuel cell arrangement and method of use that provides internal preheating of both fuel and air in order to maintain the optimum operating temperature for the production of energy. The internal preheat passes are created by the addition of two plates, one on either side of the bipolar plate, such that these plates create additional passes through the fuel cell. This internal preheat fuel cell configuration and method reduce the requirements for external heat exchanger units and air compressors. Air or fuel may be added to the fuel cell as required to maintain the optimum operating temperature through a cathode control valve or an anode control valve, respectively. A control loop comprises a temperature sensing means within the preheat air and fuel passes, a means to compare the measured temperature to a set point temperature and a determination based on the comparison as to whether the control valves should allow additional air or fuel into the preheat or bypass manifolds of the fuel cell.

  6. Systemic Administration of Allogeneic Mesenchymal Stem Cells Does Not Halt Osteoporotic Bone Loss in Ovariectomized Rats

    PubMed Central

    Sun, Yuxin; Lin, Sien; Gu, Weidong; Liu, Yamei; Zhang, Jinfang; Chen, Lin; Li, Gang

    2016-01-01

    Mesenchymal stem cells (MSCs) have innate ability to self-renew and immunosuppressive functions, and differentiate into various cell types. They have become a promising cell source for treating many diseases, particular for bone regeneration. Osteoporosis is a common metabolic bone disorder with elevated systemic inflammation which in turn triggers enhanced bone loss. We hypothesize that systemic infusion of MSCs may suppress the elevated inflammation in the osteoporotic subjects and slow down bone loss. The current project was to address the following two questions: (1) Will a single dose systemic administration of allogenic MSCs have any effect on osteoporotic bone loss? (2) Will multiple administration of allogenic MSCs from single or multiple donors have similar effect on osteoporotic bone loss? 18 ovariectomized (OVX) rats were assigned into 3 groups: the PBS control group, MSCs group 1 (receiving 2x106 GFP-MSCs at Day 10, 46, 91 from the same donor following OVX) and MSCs group 2 (receiving 2x106 GFP-MSCs from three different donors at Day 10, 46, 91). Examinations included Micro-CT, serum analysis, mechanical testing, immunofluorescence staining and bone histomorphometry analysis. Results showed that BV/TV at Day 90, 135, BMD of TV and trabecular number at Day 135 in the PBS group were significantly higher than those in the MSCs group 2, whereas trabecular spacing at Day 90, 135 was significantly smaller than that in MSCs group 2. Mechanical testing data didn’t show significant difference among the three groups. In addition, the ELISA assay showed that level of Rantes in serum in MSCs group 2 was significantly higher than that of the PBS group, whereas IL-6 and IL-10 were significantly lower than those of the PBS group. Bone histomorphometry analysis showed that Oc.S/BS and Oc.N/BS in the PBS group were significant lower than those in MSCs group 2; Ob.S/BS and Ob.N/BS did not show significant difference among the three groups. The current study

  7. The effect of internal air bleed on CO poisoning in a proton exchange membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Wang, Wentao

    It is found that carbon monoxide (CO) poisoning could be mitigated by increasing only cathode backpressure for a proton exchange membrane fuel cell (PEMFC) with ultra-thin membranes (≤25 μm). This mitigation can be explained by a heterogeneous oxidation of CO on a Pt-Ru/C anode by the permeated O 2 which is known as "internal air bleed" in his paper. A steady-state model which accounts for this internal air bleed has been developed to model the Pt-Ru/C anode polarization data when 50 ppm CO in H 2 is used as anode feed gas. The modeling results show that the mitigation of CO poisoning by the internal air bleed even exists at ambient conditions for a PEMFC with an ultra-thin membrane. Therefore, the effect of internal air bleed must be considered for modeling fuel cell performance or anode polarization data if an ultra-thin membrane and a low level of CO concentration are used for a Pt-Ru/C anode. An empirical relationship between the amount of internal air bleed used for the mitigation of CO poisoning and the fraction of free Pt sites is provided to facilitate the inclusion of an internal air bleed term in the modeling of anode polarization and the fuel cell performance.

  8. Excellence in Higher Education as Defined by Legislators and Public and Private Institutions Administrators. AIR 1991 Annual Forum Paper.

    ERIC Educational Resources Information Center

    Munoz, Grisel; And Others

    This report presents the results of a delphi study used to determine the criteria for defining excellence in higher education. An open questionnaire was administered to the commissions on education of the Puerto Rico Legislature, the administrators and governing boards of the major public and private postsecondary institutions in Puerto Rico, and…

  9. Attitudes of School Administrators and Teachers towards the "Smoke-Free Air Zone" Policy in Turkish Schools

    ERIC Educational Resources Information Center

    Banoglu, Köksal

    2013-01-01

    Objective: Schools are likely to be better able to achieve compliance with smoke-free regulations if principals and teachers perceive the importance of a smoke-free policy. The purpose of this study was to measure teacher and administrator attitudes towards the smoke-free policy in Turkish schools, which promotes a total smoking ban. Method: The…

  10. 40 CFR 22.34 - Supplemental rules governing the administrative assessment of civil penalties under the Clean Air...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... administrative proceedings to assess a civil penalty conducted under sections 113(d), 205(c), 211(d), and 213(d... notice. Prior to the issuance of a final order assessing a civil penalty, the person to whom the order is to be issued shall be given written notice of the proposed issuance of the order. Service of...

  11. DNA damage and mitochondria dysfunction in cell apoptosis induced by nonthermal air plasma

    SciTech Connect

    Kim, G. J.; Lee, J. K.; Kim, W.; Kim, K. T.

    2010-01-11

    Nonthermal plasma is known to induce animal cell death but the mechanism is not yet clear. Here, cellular and biochemical regulation of cell apoptosis is demonstrated for plasma treated cells. Surface type nonthermal air plasma triggered apoptosis of B16F10 mouse melanoma cancer cells causing DNA damage and mitochondria dysfunction. Plasma treatment activated caspase-3, apoptosis executioner. The plasma treated cells also accumulated gamma-H2A.X, marker for DNA double strand breaks, and p53 tumor suppressor gene as a response to DNA damage. Interestingly, cytochrome C was released from mitochondria and its membrane potential was changed significantly.

  12. DNA damage and mitochondria dysfunction in cell apoptosis induced by nonthermal air plasma

    NASA Astrophysics Data System (ADS)

    Kim, G. J.; Kim, W.; Kim, K. T.; Lee, J. K.

    2010-01-01

    Nonthermal plasma is known to induce animal cell death but the mechanism is not yet clear. Here, cellular and biochemical regulation of cell apoptosis is demonstrated for plasma treated cells. Surface type nonthermal air plasma triggered apoptosis of B16F10 mouse melanoma cancer cells causing DNA damage and mitochondria dysfunction. Plasma treatment activated caspase-3, apoptosis executioner. The plasma treated cells also accumulated gamma-H2A.X, marker for DNA double strand breaks, and p53 tumor suppressor gene as a response to DNA damage. Interestingly, cytochrome C was released from mitochondria and its membrane potential was changed significantly.

  13. Photodynamic therapy by topical meso-tetraphenylporphinesulfonate tetrasodium salt administration in superficial basal cell carcinomas

    SciTech Connect

    Santoro, O.; Bandieramonte, G.; Melloni, E.; Marchesini, R.; Zunino, F.; Lepera, P.; De Palo, G. )

    1990-08-01

    The efficacy of an originally developed photodynamic approach, using topical administration of tetraphenylporphinesulfonate as the photosensitizer, was evaluated in a series of 292 basal cell carcinoma lesions (less than 2-mm thick) in 50 treated patients. The lack of indication for conventional therapies was the main selection criterion. The photosensitizing agent (2% solution) was topically applied at 0.1 ml/cm2, followed by light irradiation with a dye laser emitting at 645 nm (120 or 150 J/cm2). After initial treatment, all lesions responded, with 273 (93.5%) complete responses. Recurrences were observed in 29 (10.6%). A second application of photoradiation was performed in 15 persistent lesions and 11 relapsed lesions, producing 19/26 complete responses. Our results suggest that this technique can be considered a promising alternative treatment modality in selected cases of superficial basal cell carcinomas.

  14. Vitamin E alters alveolar type II cell phospholipid synthesis in oxygen and air

    SciTech Connect

    Kennedy, K.A.; Snyder, J.M.; Stenzel, W.; Saito, K.; Warshaw, J.B. )

    1990-11-01

    Newborn rats were injected with vitamin E or placebo daily until 6 days after birth. The effect of vitamin E pretreatment on in vitro surfactant phospholipid synthesis was examined in isolated type II cells exposed to oxygen or air form 24 h in vitro. Type II cells were also isolated from untreated 6-day-old rats and cultured for 24 h in oxygen or air with control medium or vitamin E supplemented medium. These cells were used to examine the effect of vitamin E exposure in vitro on type II cell phospholipid synthesis and ultrastructure. Phosphatidylcholine (PC) synthesis was reduced in cells cultured in oxygen as compared with air. This decrease was not prevented by in vivo pretreatment or in vitro supplementation with vitamin E. Vitamin E pretreatment increased the ratio of disaturated PC to total PC and increased phosphatidylglycerol synthesis. The volume density of lamellar bodies in type II cells was increased in cells maintained in oxygen. Vitamin E did not affect the volume density of lamellar bodies. We conclude that in vitro hyperoxia inhibits alveolar type II cell phosphatidylcholine synthesis without decreasing lamellar body volume density and that supplemental vitamin E does not prevent hyperoxia-induced decrease in phosphatidylcholine synthesis.

  15. DNA methylation profile of Aire-deficient mouse medullary thymic epithelial cells

    PubMed Central

    2012-01-01

    Background Medullary thymic epithelial cells (mTECs) are characterized by ectopic expression of self-antigens during the establishment of central tolerance. The autoimmune regulator (Aire), which is specifically expressed in mTECs, is responsible for the expression of a large repertoire of tissue-restricted antigens (TRAs) and plays a role in the development of mTECs. However, Aire-deficient mTECs still express TRAs. Moreover, a subset of mTECs, which are considered to be at a stage of terminal differentiation, exists in the Aire-deficient thymus. The phenotype of a specific cell type in a multicellular organism is governed by the epigenetic regulation system. DNA methylation modification is an important component of this system. Every cell or tissue type displays a DNA methylation profile, consisting of tissue-dependent and differentially methylated regions (T-DMRs), and this profile is involved in cell-type-specific genome usage. The aim of this study was to examine the DNA methylation profile of mTECs by using Aire-deficient mTECs as a model. Results We identified the T-DMRs of mTECs (mTEC-T-DMRs) via genome-wide DNA methylation analysis of Aire−/− mTECs by comparison with the liver, brain, thymus, and embryonic stem cells. The hypomethylated mTEC-T-DMRs in Aire−/− mTECs were associated with mTEC-specific genes, including Aire, CD80, and Trp63, as well as other genes involved in the RANK signaling pathway. While these mTEC-T-DMRs were also hypomethylated in Aire+/+ mTECs, they were hypermethylated in control thymic stromal cells. We compared the pattern of DNA methylation levels at a total of 55 mTEC-T-DMRs and adjacent regions and found that the DNA methylation status was similar for Aire+/+ and Aire−/− mTECs but distinct from that of athymic cells and tissues. Conclusions These results indicate a unique DNA methylation profile that is independent of Aire in mTECs. This profile is distinct from other cell types in the thymic microenvironment and is

  16. Pluripotent stem cells in translation: a Food and Drug Administration-National Institutes of Health collaboration.

    PubMed

    Kleitman, Naomi; Rao, Mahendra S; Owens, David F

    2013-07-01

    Recently, the U.S. Food and Drug Administration (FDA), the U.S. National Institutes of Health, and the stem cell research community have collaborated on a series of workshops that address moving pluripotent stem cell therapies into the clinic. The first two workshops in the series focused on preclinical science, and a third, future workshop will focus on clinical trials. This summary addresses major points from both of the recent preclinically focused meetings. When entering into a therapeutics developmental program based on pluripotent cells, investigators must make decisions at the very early stages that will have major ramifications during later phases of development. Presentations and discussions from both invited participants and FDA staff described the need to characterize and document the quality, variability, and suitability of the cells and commercial reagents used at every translational stage. This requires consideration of future regulatory requirements, ranging from donor eligibility of the original source material to the late-stage manufacturing protocols. Federal, industrial, and academic participants agreed that planning backward is the best way to anticipate what evidence will be needed to justify human testing of novel therapeutics and to eliminate wasted efforts.

  17. In vitro organotin administration alters guinea pig cochlear outer hair cell shape and viability.

    PubMed

    Clerici, W J; Chertoff, M E; Brownell, W E; Fechter, L D

    1993-06-01

    Trimethyltin (TMT) and triethyltin (TET) disrupt auditory function at doses far below those shown to be neurotoxic. In vivo studies suggest that the initial effect of TMT on hearing occurs at the inner hair cell/spiral ganglion cell synapse, while later, the outer hair cell (OHC) undergoes structural and functional damage. TET produces acute effects upon afferent neurotransmission similar to those observed following TMT, but TET's effects on OHC structure and function have not been examined. OHCs are motile elements within the cochlea, believed to modulate the sensitivity and tuning within the inner ear. Changes in OHC length may alter hearing function, and length changes have been reported following exposure to various ototoxic agents in vitro. In the present study, 77 OHCs from 45 pigmented male guinea pigs were isolated in primary culture and exposed for 90 min to concentrations between 30 microM and 1.0 mM of TMT or TET and then to bathing medium for 30 min to remove the toxicant. Significant shortening of the OHC cell body occurred at all doses to both organotins, with a mean reduction in length of 15.1 and 20.2% for 1.0 mM TMT and TET, respectively, at the end of testing; control cells were only 3.4% shorter at the end of 90 min of perfusion with bathing medium. The effect of organotin exposure on OHC volume was not consistently related to either TMT or TET concentration or altered cell length. In addition, disruption of the plasma membrane characterized by bleb formation, the forceful ejection of cytoplasm, or bursting was seen in 80% of cells exposed to 1.0 mM TET, although not TMT; lower concentrations of both organotins disrupted the cell membrane in 10-30% of cells. Membrane rupture was not reliably associated with either increased cell volume or decreased length, implicating a weakening of the plasma membrane or cortical lattice as the basis for this effect. Consistent with the irreversible structural weakening of the lateral wall, resorption of

  18. Human alveolar epithelial cells expressing tight junctions to model the air-blood barrier.

    PubMed

    Kuehn, Anna; Kletting, Stephanie; de Souza Carvalho-Wodarz, Cristiane; Repnik, Urska; Griffiths, Gareth; Fischer, Ulrike; Meese, Eckart; Huwer, Hanno; Wirth, Dagmar; May, Tobias; Schneider-Daum, Nicole; Lehr, Claus-Michael

    2016-01-01

    This paper describes a new human alveolar epithelial cell line (hAELVi - human Alveolar Epithelial Lentivirus immortalized) with type I-like characteristics and functional tight junctions, suitable to model the air-blood barrier of the peripheral lung. Primary human alveolar epithelial cells were immortalized by a novel regimen, grown as monolayers on permeable filter supports and characterized morphologically, biochemically and biophysically. hAELVi cells maintain the capacity to form tight intercellular junctions, with high trans-epithelial electrical resistance (> 1000 Ω*cm²). The cells could be kept in culture over several days, up to passage 75, under liquid-liquid as well as air-liquid conditions. Ultrastructural analysis and real time PCR revealed type I-like cell properties, such as the presence of caveolae, expression of caveolin-1, and absence of surfactant protein C. Accounting for the barrier properties, inter-digitations sealed with tight junctions and desmosomes were also observed. Low permeability of the hydrophilic marker sodium fluorescein confirmed the suitability of hAELVi cells for in vitro transport studies across the alveolar epithelium. These results suggest that hAELVi cells reflect the essential features of the air-blood barrier, as needed for an alternative to animal testing to study absorption and toxicity of inhaled drugs, chemicals and nanomaterials. PMID:26985677

  19. Isolation of mouse respiratory epithelial cells and exposure to experimental cigarette smoke at air liquid interface.

    PubMed

    Lam, Hilaire C; Choi, Augustine M K; Ryter, Stefan W

    2011-01-01

    Pulmonary epithelial cells can be isolated from the respiratory tract of mice and cultured at air-liquid interface (ALI) as a model of differentiated respiratory epithelium. A protocol is described for isolating and exposing these cells to mainstream cigarette smoke (CS), in order to study epithelial cell responses to CS exposure. The protocol consists of three parts: the isolation of airway epithelial cells from mouse trachea, the culturing of these cells at air-liquid interface (ALI) as fully differentiated epithelial cells, and the delivery of calibrated mainstream CS to these cells in culture. The ALI culture system allows the culture of respiratory epithelia under conditions that more closely resemble their physiological setting than ordinary liquid culture systems. The study of molecular and lung cellular responses to CS exposure is a critical component of understanding the impact of environmental air pollution on human health. Research findings in this area may ultimately contribute towards understanding the etiology of chronic obstructive pulmonary disease (COPD), and other tobacco-related diseases, which represent major global health problems. PMID:21372793

  20. Systemic Administration of Interleukin 2 Enhances the Therapeutic Efficacy of Dendritic Cell-Based Tumor Vaccines

    NASA Astrophysics Data System (ADS)

    Shimizu, K.; Fields, R. C.; Giedlin, M.; Mule, J. J.

    1999-03-01

    We have reported previously that murine bone marrow-derived dendritic cells (DC) pulsed with whole tumor lysates can mediate potent antitumor immune responses both in vitro and in vivo. Because successful therapy was dependent on host immune T cells, we have now evaluated whether the systemic administration of the T cell stimulatory/growth promoting cytokine interleukin-2 (IL-2) could enhance tumor lysate-pulsed DC-based immunizations to further promote protective immunity toward, and therapeutic rejection of, syngeneic murine tumors. In three separate approaches using a weakly immunogenic sarcoma (MCA-207), the systemic administration of non-toxic doses of recombinant IL-2 (20,000 and 40,000 IU/dose) was capable of mediating significant increases in the potency of DC-based immunizations. IL-2 could augment the efficacy of tumor lysate-pulsed DC to induce protective immunity to lethal tumor challenge as well as enhance splenic cytotoxic T lymphocyte activity and interferon-γ production in these treated mice. Moreover, treatment with the combination of tumor lysate-pulsed DC and IL-2 could also mediate regressions of established pulmonary 3-day micrometastases and 7-day macrometastases as well as established 14- and 28-day s.c. tumors, leading to either significant cure rates or prolongation in overall survival. Collectively, these findings show that nontoxic doses of recombinant IL-2 can potentiate the antitumor effects of tumor lysate-pulsed DC in vivo and provide preclinical rationale for the use of IL-2 in DC-based vaccine strategies in patients with advanced cancer.

  1. Rechargeable Zn-air batteries: Progress in electrolyte development and cell configuration advancement

    NASA Astrophysics Data System (ADS)

    Xu, M.; Ivey, D. G.; Xie, Z.; Qu, W.

    2015-06-01

    Zn-air batteries, which are cost-effective and have high energy density, are promising energy storage devices for renewable energy and power sources for electric transportation. Nevertheless, limited charge and discharge cycles and low round-trip efficiency have long been barriers preventing the large-scale deployment of Zn-air batteries in the marketplace. Technology advancements for each battery component and the whole battery/cell assembly are being pursued, with some key milestones reached during the past 20 years. As an example, commercial Zn-air battery products with long lifetimes and high energy efficiencies are being considered for grid-scale energy storage and for automotive markets. In this review, we present our perspectives on improvements in Zn-air battery technology through the exploration and utilization of different electrolyte systems. Recent studies ranging from aqueous electrolytes to nonaqueous electrolytes, including solid polymer electrolytes and ionic liquids, as well as hybrid electrolyte systems adopted in Zn-air batteries have been evaluated. Understanding the benefits and drawbacks of each electrolyte, as well as the fundamental electrochemistry of Zn and air electrodes in different electrolytes, are the focus of this paper. Further consideration is given to detailed Zn-air battery configurations that have been studied and applied in commercial or nearing commercial products, with the purpose of exposing state-of-the-art technology innovations and providing insights into future advancements.

  2. Autoimmune regulator (Aire) controls the expression of microRNAs in medullary thymic epithelial cells.

    PubMed

    Macedo, Claudia; Evangelista, Adriane F; Marques, Márcia M; Octacílio-Silva, Shirlei; Donadi, Eduardo A; Sakamoto-Hojo, Elza T; Passos, Geraldo A

    2013-04-01

    The autoimmune regulator (Aire) is a transcription factor that controls the ectopic expression of a large set of peripheral tissue antigen (PTA) genes in medullary thymic epithelial cells (mTECs). Recent evidence has demonstrated that Aire releases stalled RNA polymerase II (RNA Pol II) from blockage at the promoter region of its target genes. Given that, in addition to messenger RNAs (mRNA), RNA Pol II also transcribes microRNAs (miRNAs), we raised the hypothesis that Aire might play a role as an upstream controller of miRNA transcription. To test this, we initially analyzed the expression profiles of 662 miRNAs in control and Aire-silenced (siRNA) murine mTEC 3.10 cells using microarrays. The bioinformatics programs SAM and Cluster-TreeView were then used to identify the differentially expressed miRNAs and their profiles, respectively. Thirty Aire-dependent miRNAs were identified in the Aire-silenced mTECs, of which 18 were up- and 12 were down-regulated. The down-regulated miR-376 family was the focus of this study because its members (miR-376a, miR-376b and miR-376c) are located in the genome within the Gm2922 open-reading frame (ORF) gene segment on the chromosome 12F1. The T-boxes (TTATTA) and G-boxes (GATTGG), which represent putative RNA Pol II promoter motifs, were located in a portion spanning 10 kb upstream of the ATG codon of Gm2922. Moreover, we found that Gm2922 encodes an mRNA, which was also down-regulated in Aire-silenced mTECs. These results represent the first evidence that Aire can play a role as a controller of transcription of miRNAs located within genomic regions encompassing ORF and/or mRNA genes.

  3. Degradation mechanism of Cu(In,Ga)Se2 solar cells induced by exposure to air

    NASA Astrophysics Data System (ADS)

    Nishinaga, Jiro; Kamikawa, Yukiko; Koida, Takashi; Shibata, Hajime; Niki, Shigeru

    2016-07-01

    The degradation mechanism of unencapsulated Cu(In,Ga)Se2 (CIGS) solar cells upon exposure to air has been investigated. Exposure to air at room temperature slightly reduces the conversion efficiency of CIGS solar cells. However, this conversion efficiency decreases significantly under damp heat testing at 85 °C and a relative humidity of 85% for 15 h. The shunt resistance and conversion efficiency are completely recovered after removing the side edges of the CIGS solar cells by mechanical scribing. This result suggests that low-resistive layers are formed on the sidewalls of the solar cells during damp heat testing. In addition, alkaline solution etching has been confirmed to be an effective way of removing the low-resistive layers. The low-resistive layers on the sidewalls are identified to be molybdenum oxides and sodium molybdate by Auger electron spectroscopy. After etching the oxides on the sidewalls, the saturation current density and ideality factor are confirmed to be improved.

  4. Air electrode material for high temperature electrochemical cells

    DOEpatents

    Ruka, Roswell J.

    1985-01-01

    Disclosed is a solid solution with a perovskite-like crystal structure having the general formula La.sub.1-x-w (M.sub.L).sub.x (Ce).sub.w (M.sub.S1).sub.1-y (M.sub.S2).sub.y O.sub.3 where M.sub.L is Ca, Sr, Ba, or mixtures thereof, M.sub.S1 is Mn, Cr, or mixtures thereof and M.sub.S2 is Ni, Fe, Co, Ti, Al, In, Sn, Mg, Y, Nb, Ta, or mixtures thereof, w is about 0.05 to about 0.25, x+w is about 0.1 to about 0.7, and y is 0 to about 0.5. In the formula, M.sub.L is preferably Ca, w is preferably 0.1 to 0.2, x+w is preferably 0.4 to 0.7, and y is preferably 0. The solid solution can be used in an electrochemical cell where it more closely matches the thermal expansion characteristics of the support tube and electrolyte of the cell.

  5. Aluminum-air battery cell hardware development. Period covered 1 January 1982-30 April 1982

    SciTech Connect

    Not Available

    1982-04-30

    Air cathodes were evaluated to determine polarization characteristics and the effect of aluminate, stannate and carbonate concentration. Tests confirmed prior measurements by Electromedia Corporation (EMC) that polarization is about 30 mV/kAm/sup -2/ at the electrode surface. Air cathodes from another vendor exhibited comparable performance. Variation in electrolyte composition caused on only small changes (<10%) in cathode performance. The rapidly-refuelable, subscale Mark 1-2 Aluminum-Air battery (moving cathode) was evaluated. Peak power density was measured at 2.7 and 3.1 kW/m/sup 2/ which is similar to performance of the Mark 1-1 cell. Fabrication of the rapidly-refuelable, 6-cell module with 200-cm/sup 2/ moving anodes was partially completed.

  6. Metal-air cells comprising collapsible foam members and means for minimizing internal pressure buildup

    NASA Technical Reports Server (NTRS)

    Woodruff, Glenn (Inventor); Putt, Ronald A. (Inventor)

    1994-01-01

    This invention provides a prismatic zinc-air cell including, in general, a prismatic container having therein an air cathode, a separator and a zinc anode. The container has one or more oxygen access openings, and the air cathode is disposed in the container in gaseous communication with the oxygen access openings so as to allow access of oxygen to the cathode. The separator has a first side in electrolytic communication with the air cathode and a second side in electrolytic communication with the zinc anode. The separator isolates the cathode and the zinc anode from direct electrical contact and allows passage of electrolyte therebetween. An expansion chamber adjacent to the zinc anode is provided which accommodates expansion of the zinc anode during discharge of the cell. A suitable collapsible foam member generally occupies the expansion space, providing sufficient resistance tending to oppose movement of the zinc anode away from the separator while collapsing upon expansion of the zinc anode during discharge of the cell. One or more vent openings disposed in the container are in gaseous communication with the expansion space, functioning to satisfactorily minimize the pressure buildup within the container by venting gasses expelled as the foam collapses during cell discharge.

  7. COD removal characteristics in air-cathode microbial fuel cells.

    PubMed

    Zhang, Xiaoyuan; He, Weihua; Ren, Lijiao; Stager, Jennifer; Evans, Patrick J; Logan, Bruce E

    2015-01-01

    Exoelectrogenic microorganisms in microbial fuel cells (MFCs) compete with other microorganisms for substrate. In order to understand how this affects removal rates, current generation, and coulombic efficiencies (CEs), substrate removal rates were compared in MFCs fed a single, readily biodegradable compound (acetate) or domestic wastewater (WW). Removal rates based on initial test conditions fit first-order kinetics, but rate constants varied with circuit resistance. With filtered WW (100Ω), the rate constant was 0.18h(-)(1), which was higher than acetate or filtered WW with an open circuit (0.10h(-)(1)), but CEs were much lower (15-24%) than acetate. With raw WW (100Ω), COD removal proceeded in two stages: a fast removal stage with high current production, followed by a slower removal with little current. While using MFCs increased COD removal rate due to current generation, secondary processes will be needed to reduce COD to levels suitable for discharge.

  8. Extracellular vesicle in vivo biodistribution is determined by cell source, route of administration and targeting

    PubMed Central

    Wiklander, Oscar P. B.; Nordin, Joel Z.; O’Loughlin, Aisling; Gustafsson, Ylva; Corso, Giulia; Mäger, Imre; Vader, Pieter; Lee, Yi; Sork, Helena; Seow, Yiqi; Heldring, Nina; Alvarez-Erviti, Lydia; Smith, CI Edvard; Le Blanc, Katarina; Macchiarini, Paolo; Jungebluth, Philipp; Wood, Matthew J. A.; Andaloussi, Samir EL

    2015-01-01

    Extracellular vesicles (EVs) have emerged as important mediators of intercellular communication in a diverse range of biological processes. For future therapeutic applications and for EV biology research in general, understanding the in vivo fate of EVs is of utmost importance. Here we studied biodistribution of EVs in mice after systemic delivery. EVs were isolated from 3 different mouse cell sources, including dendritic cells (DCs) derived from bone marrow, and labelled with a near-infrared lipophilic dye. Xenotransplantation of EVs was further carried out for cross-species comparison. The reliability of the labelling technique was confirmed by sucrose gradient fractionation, organ perfusion and further supported by immunohistochemical staining using CD63-EGFP probed vesicles. While vesicles accumulated mainly in liver, spleen, gastrointestinal tract and lungs, differences related to EV cell origin were detected. EVs accumulated in the tumour tissue of tumour-bearing mice and, after introduction of the rabies virus glycoprotein-targeting moiety, they were found more readily in acetylcholine-receptor-rich organs. In addition, the route of administration and the dose of injected EVs influenced the biodistribution pattern. This is the first extensive biodistribution investigation of EVs comparing the impact of several different variables, the results of which have implications for the design and feasibility of therapeutic studies using EVs. PMID:25899407

  9. [Changes of biogenic amines in the thymus cell system after T-activin administration].

    PubMed

    Iastrebova, S A; Sergeeva, V E; Spirin, I V

    2004-01-01

    The aim of this work was to study the dynamics of the neurotransmitter (cateholamine, serotonin, histamine) content in the thymic structures, as well as of heparin maturation degree and degranulation in the thymic mast cells population by means of Falck, Cross and Unna luminescent-histochemical methods 1-30 days following daily T-activinum injections. Concentration of the neurotransmitters in all the bioamine-containing thymic structures was found to fall by day 7, but after day 14 it began to increase, reaching a high level by day 30 that significantly exceeded the initial values. The degree of heparin maturation in mast cells was increased at days 21 and 30. Long-term T-activinum administration (for more than 7 days) is not justified, since an excessive increase in bioamine and heparin content suppresses immune reactions. Degranulating mast cells, surrounded by the zones of microenvironment, that were saturated with the bioamines capable of suppressing thymocytes, were found to predominate at the late stages of an experiment with T-activinum injections.

  10. Sampling, storage, and analysis of C2-C7 non-methane hydrocarbons from the US National Oceanic and Atmospheric Administration Cooperative Air Sampling Network glass flasks.

    PubMed

    Pollmann, Jan; Helmig, Detlev; Hueber, Jacques; Plass-Dülmer, Christian; Tans, Pieter

    2008-04-25

    An analytical technique was developed to analyze light non-methane hydrocarbons (NMHC), including ethane, propane, iso-butane, n-butane, iso-pentane, n-pentane, n-hexane, isoprene, benzene and toluene from whole air samples collected in 2.5l-glass flasks used by the National Oceanic and Atmospheric Administration, Earth System Research Laboratory, Global Monitoring Division (NOAA ESRL GMD, Boulder, CO, USA) Cooperative Air Sampling Network. This method relies on utilizing the remaining air in these flasks (which is at below-ambient pressure at this stage) after the completion of all routine greenhouse gas measurements from these samples. NMHC in sample aliquots extracted from the flasks were preconcentrated with a custom-made, cryogen-free inlet system and analyzed by gas chromatography (GC) with flame ionization detection (FID). C2-C7 NMHC, depending on their ambient air mixing ratios, could be measured with accuracy and repeatability errors of generally < or =10-20%. Larger deviations were found for ethene and propene. Hexane was systematically overestimated due to a chromatographic co-elution problem. Saturated NMHC showed less than 5% changes in their mixing ratios in glass flask samples that were stored for up to 1 year. In the same experiment ethene and propene increased at approximately 30% yr(-1). A series of blank experiments showed negligible contamination from the sampling process and from storage (<10 pptv yr(-1)) of samples in these glass flasks. Results from flask NMHC analyses were compared to in-situ NMHC measurements at the Global Atmospheric Watch station in Hohenpeissenberg, Germany. This 9-months side-by-side comparison showed good agreement between both methods. More than 94% of all data comparisons for C2-C5 alkanes, isoprene, benzene and toluene fell within the combined accuracy and precision objectives of the World Meteorological Organization Global Atmosphere Watch (WMO-GAW) for NMHC measurements.

  11. Administration of Reconstituted Polyphenol Oil Bodies Efficiently Suppresses Dendritic Cell Inflammatory Pathways and Acute Intestinal Inflammation

    PubMed Central

    Cavalcanti, Elisabetta; Vadrucci, Elisa; Delvecchio, Francesca Romana; Addabbo, Francesco; Bettini, Simona; Liou, Rachel; Monsurrò, Vladia; Huang, Alex Yee-Chen; Pizarro, Theresa Torres

    2014-01-01

    Polyphenols are natural compounds capable of interfering with the inflammatory pathways of several in vitro model systems. In this study, we developed a stable and effective strategy to administer polyphenols to treat in vivo models of acute intestinal inflammation. The in vitro suppressive properties of several polyphenols were first tested and compared for dendritic cells (DCs) production of inflammatory cytokines. A combination of the polyphenols, quercetin and piperine, were then encapsulated into reconstituted oil bodies (OBs) in order to increase their stability. Our results showed that administration of low dose reconstituted polyphenol OBs inhibited LPS-mediated inflammatory cytokine secretion, including IL-6, IL-23, and IL-12, while increasing IL-10 and IL-1Rα production. Mice treated with the polyphenol-containing reconstituted OBs (ROBs) were partially protected from dextran sodium sulfate (DSS)-induced colitis and associated weight loss, while mortality and inflammatory scores revealed an overall anti-inflammatory effect that was likely mediated by impaired DC immune responses. Our study indicates that the administration of reconstituted quercetin and piperine-containing OBs may represent an effective and potent anti-inflammatory strategy to treat acute intestinal inflammation. PMID:24558444

  12. Remote ischemic postconditioning enhances cell retention in the myocardium after intravenous administration of bone marrow mesenchymal stromal cells.

    PubMed

    Jiang, Qin; Song, Peng; Wang, Enshi; Li, Jun; Hu, Shengshou; Zhang, Hao

    2013-03-01

    Efficacy of intravenous administration of mesenchymal stromal cells (MSCs) for myocardial infarction (MI) is limited by low cell retention in the damaged myocardium. Previous studies indicated that remote ischemic conditioning could protect against ischemia-reperfusion-induced injury by release of various cytokines including stromal cell derived factor-1 alpha (SDF-1α). However, whether remote ischemic postconditioning (RIPostC) can also enhance the retention of infused cells in the myocardium by activating MSC homing is unclear. In this study, RIPostC was induced with 4cycles of 5min occlusion and reperfusion of the abdominal aorta in female Sprague-Dawley (SD) rats which underwent ligation of the coronary artery 1week previously. Cytokine levels in serum and myocardium were evaluated by enzyme-linked immunosorbent assay (ELISA) at 1, 6, 24 and 48h after RIPostC. Then, a total of 4×10(6) male MSCs were infused intravenously at 24h after RIPostC. The number of survived cells in the myocardium was evaluated by real-time polymerase chain reaction analysis for Y chromosome and the heart function was evaluated by echocardiography at 1month after cell infusion. Furthermore, 10μg/kg rabbit anti-rat CXCR4 polyclonal antibody was injected intraperitoneally to prove the role of SDF-1α for RIPostC. RIPostC induced an increase in SDF-1α in serum at 1h and enhanced SDF-1α transcription and protein synthesis in the myocardium at 24h after the procedure. 1month after cell transplantation, RIPostC significantly increased MSC myocardial retention by 79.1±12.3% and thereby contributed to enhanced cardiac function in comparison with cell transplantation without RIPostC. Furthermore, blockade with a CXCR4-specific antibody after RIPostC markedly attenuated the enhancement of therapeutic efficacy. We conclude that RIPostC activated SDF-1α expression and enhanced retention of the infused MSCs in the injured myocardium. Priming of the heart with RIPostC might be a novel

  13. Relationships of eggshell, air cell, and cloacal temperatures of embryonated broiler hatching eggs during incubation.

    PubMed

    Olojede, O C; Collins, K E; Womack, S K; Gerard, P D; Peebles, E D

    2016-10-01

    The relationships of eggshell, air cell, and embryo cloacal temperatures in Ross × Ross 708 broiler hatching eggs were determined. Twenty eggs were weighed and set on each of 3 tray levels of a single incubator. Eggshell temperature (EST) of the eggs were recorded once in the morning (AM) and afternoon (PM) between 0 and 19 d of incubation (DOI) using an infrared thermometer (IRT). All eggs were candled and a transponder was implanted in the air cell of eggs containing live embryos (12 per tray level) at 12 DOI. At 19 DOI, transponders were implanted in the cloaca of live embryos from those same eggs. Air cell temperature (ACT) and EST readings were recorded once in the AM and PM between 12 and 19 DOI, and ACT and cloaca temperature (CLT) readings were recorded every 6 h between 19 and 21 DOI. The EST and ACT readings between 13 and 19 DOI were positively correlated. However, their respective mean temperatures between 13 and 19 DOI differed. The EST and ACT were not significantly influenced by tray level. Nevertheless, a main effect due to location (eggshell vs. air cell), and an interaction between DOI and time of day (AM and PM) in the 13 to 19 DOI interval were observed. Furthermore, an interaction was observed between location (air cell and cloaca) and the 6 h sequential time periods in the 19 to 21 DOI interval. However, across the entire 19 to 21 DOI interval, mean ACT and CLT were not significantly different, and were positively correlated. These data suggest that ACT readings are higher than those of EST during the last half of incubation, and that between 13 and 19 DOI, ACT readings may have the potential for use as a minimally invasive method by which to more accurately estimate the true core body temperature of broiler embryos. The effects of this method on hatchability and post-hatch performance need determination to better establish its practicality.

  14. Abstract: Air, Thermal and Water Management for PEM Fuel Cell Systems

    SciTech Connect

    Mark K. Gee Zia Mirza

    2008-10-01

    PEM fuel cells are excellent candidates for transportation applications due to their high efficiencies. PEM fuel cell Balance of Plant (BOP) components, such as air, thermal, and water management sub-systems, can have a significant effect on the overall system performance, but have traditionally not been addressed in research and development efforts. Recognizing this, the U.S. Department of Energy and Honeywell International Inc. are funding an effort that emphasizes the integration and optimization of air, thermal and water management sub-systems. This effort is one of the major elements to assist the fuel cell system developers and original equipment manufacturers to achieve the goal of an affordable and efficient power system for transportation applications. Past work consisted of: (1) Analysis, design, and fabrication of a motor driven turbocompressor. (2) A systematic trade study to select the most promising water and thermal management systems from five different concepts (absorbent wheel humidifier, gas to gas membrane humidifier, porous metal foam humidifier, cathode recycle compressor, and water injection pump.) This presentation will discuss progress made in the research and development of air, water and thermal management sub-systems for PEM fuel cell systems in transportation applications. More specifically, the presentation will discuss: (1) Progress of the motor driven turbocompressor design and testing; (2) Progress of the humidification component selection and testing; and (3) Progress of the thermal management component preliminary design. The programs consist of: (1) The analysis, design, fabrication and testing of a compact motor driven turbocompressor operating on foil air bearings to provide contamination free compressed air to the fuel cell stack while recovering energy from the exhaust streams to improve system efficiency. (2) The analysis, design, fabrication and testing of selected water and thermal management systems and components to

  15. Relationships of eggshell, air cell, and cloacal temperatures of embryonated broiler hatching eggs during incubation.

    PubMed

    Olojede, O C; Collins, K E; Womack, S K; Gerard, P D; Peebles, E D

    2016-10-01

    The relationships of eggshell, air cell, and embryo cloacal temperatures in Ross × Ross 708 broiler hatching eggs were determined. Twenty eggs were weighed and set on each of 3 tray levels of a single incubator. Eggshell temperature (EST) of the eggs were recorded once in the morning (AM) and afternoon (PM) between 0 and 19 d of incubation (DOI) using an infrared thermometer (IRT). All eggs were candled and a transponder was implanted in the air cell of eggs containing live embryos (12 per tray level) at 12 DOI. At 19 DOI, transponders were implanted in the cloaca of live embryos from those same eggs. Air cell temperature (ACT) and EST readings were recorded once in the AM and PM between 12 and 19 DOI, and ACT and cloaca temperature (CLT) readings were recorded every 6 h between 19 and 21 DOI. The EST and ACT readings between 13 and 19 DOI were positively correlated. However, their respective mean temperatures between 13 and 19 DOI differed. The EST and ACT were not significantly influenced by tray level. Nevertheless, a main effect due to location (eggshell vs. air cell), and an interaction between DOI and time of day (AM and PM) in the 13 to 19 DOI interval were observed. Furthermore, an interaction was observed between location (air cell and cloaca) and the 6 h sequential time periods in the 19 to 21 DOI interval. However, across the entire 19 to 21 DOI interval, mean ACT and CLT were not significantly different, and were positively correlated. These data suggest that ACT readings are higher than those of EST during the last half of incubation, and that between 13 and 19 DOI, ACT readings may have the potential for use as a minimally invasive method by which to more accurately estimate the true core body temperature of broiler embryos. The effects of this method on hatchability and post-hatch performance need determination to better establish its practicality. PMID:27433009

  16. Assessment of methanol electro-oxidation for direct methanol-air fuel cells

    SciTech Connect

    Fritts, S.D.; Sen, R.K.

    1988-07-01

    The Office of Energy Storage and Distribution of the US Department of Energy (DOE) supports the development of a methanol-air fuel cell for transportation application. The approach used at Los Alamos National Laboratory converts the methanol fuel to a hydrogen-rich gas in a reformer, then operates the fuel cell on hydrogen and air. The reformer tends to be bulky (raising vehicle packaging problems), has a long startup period, and is not well suited for the transient operation required in a vehicle. Methanol, however, can be oxidized electrochemically in the fuel cell. If this process can be conducted efficiently, a direct methanol-air fuel cell can be used, which does not require a reformer. The objective of this study is to assess the potential of developing a suitable catalyst for the direct electrochemical oxidation of methanol. The primary conclusion of this study is that no acceptable catalysts exist can efficiently oxidize methanol electrochemically and have the desired cost and lifetime for vehicle applications. However, recent progress in understanding the mechanism of methanol oxidation indicates that a predictive base can be developed to search for methanol oxidation catalysts and can be used to methodically develop improved catalysts. Such an approach is strongly recommended. The study also recommends that until further progress in developing high-performance catalysts is achieved, research in cell design and testing is not warranted. 43 refs., 12 figs., 1 tab.

  17. Tolerance of non-platinum group metals cathodes proton exchange membrane fuel cells to air contaminants

    NASA Astrophysics Data System (ADS)

    Reshetenko, Tatyana; Serov, Alexey; Artyushkova, Kateryna; Matanovic, Ivana; Sarah Stariha; Atanassov, Plamen

    2016-08-01

    The effects of major airborne contaminants (SO2, NO2 and CO) on the spatial performance of Fe/N/C cathode membrane electrode assemblies were studied using a segmented cell system. The injection of 2-10 ppm SO2 in air stream did not cause any performance decrease and redistribution of local currents due to the lack of stably adsorbed SO2 molecules on Fe-Nx sites, as confirmed by density functional theory (DFT) calculations. The introduction of 5-20 ppm of CO into the air stream also did not affect fuel cell performance. The exposure of Fe/N/C cathodes to 2 and 10 ppm NO2 resulted in performance losses of 30 and 70-75 mV, respectively. DFT results showed that the adsorption energies of NO2 and NO were greater than that of O2, which accounted for the observed voltage decrease and slight current redistribution. The cell performance partially recovered when the NO2 injection was stopped. The long-term operation of the fuel cells resulted in cell performance degradation. XPS analyses of Fe/N/C electrodes revealed that the performance decrease was due to catalyst degradation and ionomer oxidation. The latter was accelerated in the presence of air contaminants. The details of the spatial performance and electrochemical impedance spectroscopy results are presented and discussed.

  18. Tolerance of non-platinum group metals cathodes proton exchange membrane fuel cells to air contaminants

    NASA Astrophysics Data System (ADS)

    Reshetenko, Tatyana; Serov, Alexey; Artyushkova, Kateryna; Matanovic, Ivana; Sarah Stariha; Atanassov, Plamen

    2016-08-01

    The effects of major airborne contaminants (SO2, NO2 and CO) on the spatial performance of Fe/N/C cathode membrane electrode assemblies were studied using a segmented cell system. The injection of 2-10 ppm SO2 in air stream did not cause any performance decrease and redistribution of local currents due to the lack of stably adsorbed SO2 molecules on Fe-Nx sites, as confirmed by density functional theory (DFT) calculations. The introduction of 5-20 ppm of CO into the air stream also did not affect fuel cell performance. The exposure of Fe/N/C cathodes to 2 and 10 ppm NO2 resulted in performance losses of 30 and 70-75 mV, respectively. DFT results showed that the adsorption energies of NO2 and NO were greater than that of O2, which accounted for the observed voltage decrease and slight current redistribution. The cell performance partially recovered when the NO2 injection was stopped. The long-term operation of the fuel cells resulted in cell performance degradation. XPS analyses of Fe/N/C electrodes revealed that the performance decrease was due to catalyst degradation and ionomer oxidation. The latter was accelerated in the presence of air contaminants. The details of the spatial performance and electrochemical impedance spectroscopy results are presented and discussed.

  19. Free air breathing proton exchange membrane fuel cell: Thermal behavior characterization near freezing temperature

    NASA Astrophysics Data System (ADS)

    Higuita Cano, Mauricio; Kelouwani, Sousso; Agbossou, Kodjo; Dubé, Yves

    2014-01-01

    A free air breathing fuel cell thermal model is developed. This proton exchange membrane fuel cell (PEMFC) has been selected as the basis for the study due to its use in automotive applications. The blowers integrated to the stack provide the required air flow for hydrogen oxidation as well as the fluid for the stack thermal regulation. Hence, their controls are a key point for keeping the system to maximum efficiency. Using well-known fuel cell electrochemistry, a dynamic thermal model near freezing temperature, which includes the stack physical parameters, is developed and validated. In addition to these parameters, only the inlet and outlet air temperatures are used to derive the model. Experimental validation with a real 1 kW free air breathing PEMFC has demonstrated that the model can reasonably track the stack internal temperature with a maximum deviation between the observed and the estimated temperatures of 5%. Therefore, the proposed method will allow the development of efficient blower management systems for PEMFC efficiency improvement.

  20. The 2006 Cape Canaveral Air Force Station Range Reference Atmosphere Model Validation Study and Sensitivity Analysis to the National Aeronautics and Space Administration's Space Shuttle

    NASA Technical Reports Server (NTRS)

    Burns, Lee; Merry, Carl; Decker, Ryan; Harrington, Brian

    2008-01-01

    The 2006 Cape Canaveral Air Force Station (CCAFS) Range Reference Atmosphere (RRA) is a statistical model summarizing the wind and thermodynamic atmospheric variability from surface to 70 kin. Launches of the National Aeronautics and Space Administration's (NASA) Space Shuttle from Kennedy Space Center utilize CCAFS RRA data to evaluate environmental constraints on various aspects of the vehicle during ascent. An update to the CCAFS RRA was recently completed. As part of the update, a validation study on the 2006 version was conducted as well as a comparison analysis of the 2006 version to the existing CCAFS RRA database version 1983. Assessments to the Space Shuttle vehicle ascent profile characteristics were performed to determine impacts of the updated model to the vehicle performance. Details on the model updates and the vehicle sensitivity analyses with the update model are presented.

  1. The 2006 Cape Canaveral Air Force Station Range Reference Atmosphere Model Validation Study and Sensitivity Analysis to the National Aeronautics and Space Administration's Space Shuttle

    NASA Technical Reports Server (NTRS)

    Decker, Ryan K.; Burns, Lee; Merry, Carl; Harrington, Brian

    2008-01-01

    Atmospheric parameters are essential in assessing the flight performance of aerospace vehicles. The effects of the Earth's atmosphere on aerospace vehicles influence various aspects of the vehicle during ascent ranging from its flight trajectory to the structural dynamics and aerodynamic heatmg on the vehicle. Atmospheric databases charactenzing the wind and thermodynamic environments, known as Range Reference Atmospheres (RRA), have been developed at space launch ranges by a governmental interagency working group for use by aerospace vehicle programs. The National Aeronantics and Space Administration's (NASA) Space Shuttle Program (SSP), which launches from Kennedy Space Center, utilizes atmosphenc statistics derived from the Cape Canaveral Air Force Station Range Reference Atmosphere (CCAFS RRA) database to evaluate environmental constraints on various aspects of the vehlcle during ascent.

  2. Aire regulates the transfer of antigen from mTECs to dendritic cells for induction of thymic tolerance.

    PubMed

    Hubert, François-Xavier; Kinkel, Sarah A; Davey, Gayle M; Phipson, Belinda; Mueller, Scott N; Liston, Adrian; Proietto, Anna I; Cannon, Ping Z F; Forehan, Simon; Smyth, Gordon K; Wu, Li; Goodnow, Christopher C; Carbone, Francis R; Scott, Hamish S; Heath, William R

    2011-09-01

    To investigate the role of Aire in thymic selection, we examined the cellular requirements for generation of ovalbumin (OVA)-specific CD4 and CD8 T cells in mice expressing OVA under the control of the rat insulin promoter. Aire deficiency reduced the number of mature single-positive OVA-specific CD4(+) or CD8(+) T cells in the thymus, independent of OVA expression. Importantly, it also contributed in 2 ways to OVA-dependent negative selection depending on the T-cell type. Aire-dependent negative selection of OVA-specific CD8 T cells correlated with Aire-regulated expression of OVA. By contrast, for OVA-specific CD4 T cells, Aire affected tolerance induction by a mechanism that operated independent of the level of OVA expression, controlling access of antigen presenting cells to medullary thymic epithelial cell (mTEC)-expressed OVA. This study supports the view that one mechanism by which Aire controls thymic negative selection is by regulating the indirect presentation of mTEC-derived antigens by thymic dendritic cells. It also indicates that mTECs can mediate tolerance by direct presentation of Aire-regulated antigens to both CD4 and CD8 T cells.

  3. Investigation of novel electrolyte systems for advanced metal/air batteries and fuel cells

    NASA Astrophysics Data System (ADS)

    Ye, Hui

    It is a worldwide challenge to develop advanced green power sources for modern portable devices, transportation and stationary power generation. Metal/air batteries and fuel cells clearly stand out in view of their high specific energy, high energy efficiency and environment-friendliness. Advanced metal/air batteries based on metal ion conductors and proton exchange membrane (PEM) fuel cells operated at elevated temperatures (>120°C) can circumvent the limitations of current technologies and bring considerable advantages. The key is to develop suitable electrolytes to enable these new technologies. In this thesis research, investigation of novel electrolytes systems for advanced metal/air batteries and PEM fuel cells is conducted. Novel polymer gel electrolyte systems, [metal salt/ionic liquid/polymer] and [metal salt/liquid polyether/polymer] are prepared. Such systems contain no volatile solvents, conduct metal ions (Li+ or Zn 2+) with high ionic conductivity, possess wide electrochemical stability windows, and exhibit wide operating temperature ranges. They promise to enable non-aqueous, all-solid-state, thin-film Li/air batteries and Zn/air batteries. They are advantageous for application in other battery systems as well, such as rechargeable lithium and lithium ion batteries. In the case of proton exchange membranes, polymer gel electrolyte systems [acid/ionic liquid/polymer] are prepared. Especially, H3PO4/PMIH2PO 4/PBI is demonstrated as prospective proton exchange membranes for PEM fuel cells operating at elevated temperatures. Comprehensive electrochemical characterization, thermal analysis (TGA and DSC) and spectroscopy analysis (NMR and FTIR) are carried out to investigate these novel electrolyte systems and their ion transport mechanisms. The design and synthesis of novel ionic liquids and electrolyte systems based on them for advantageous application in various electrochemical power sources are highlighted in this work.

  4. Biphasic Aire expression in early embryos and in medullary thymic epithelial cells before end-stage terminal differentiation.

    PubMed

    Nishikawa, Yumiko; Hirota, Fumiko; Yano, Masashi; Kitajima, Hiroyuki; Miyazaki, Jun-ichi; Kawamoto, Hiroshi; Mouri, Yasuhiro; Matsumoto, Mitsuru

    2010-05-10

    The roles of autoimmune regulator (Aire)-expressing medullary thymic epithelial cells (mTECs) in the organization of the thymic microenvironment for establishing self-tolerance are enigmatic. We sought to monitor the production and maintenance of Aire-expressing mTECs by a fate-mapping strategy in which bacterial artificial chromosome transgenic (Tg) mice expressing Cre recombinase under the control of the Aire regulatory element were crossed with a GFP reporter strain. We found that, in addition to its well recognized expression within mature mTECs, Aire was expressed in the early embryo before emergence of the three germ cell layers. This observation may help to explain the development of ectodermal dystrophy often seen in patients with AIRE deficiency. With the use of one Tg line in which Cre recombinase expression was confined to mTECs, we found that Aire(+)CD80(high) mTECs further progressed to an Aire(-)CD80(intermediate) stage, suggesting that Aire expression is not constitutive from after its induction until cell death but instead is down-regulated at the beginning of terminal differentiation. We also demonstrated that many mTECs of Aire-expressing lineage are in close contact with thymic dendritic cells. This close proximity may contribute to transfer of tissue-restricted self-antigens expressed by mTECs to professional antigen-presenting cells.

  5. Culturing of Human Nasal Epithelial Cells at the Air Liquid Interface

    PubMed Central

    Müller, Loretta; Brighton, Luisa E.; Carson, Johnny L.; Fischer, William A.; Jaspers, Ilona

    2013-01-01

    In vitro models using human primary epithelial cells are essential in understanding key functions of the respiratory epithelium in the context of microbial infections or inhaled agents. Direct comparisons of cells obtained from diseased populations allow us to characterize different phenotypes and dissect the underlying mechanisms mediating changes in epithelial cell function. Culturing epithelial cells from the human tracheobronchial region has been well documented, but is limited by the availability of human lung tissue or invasiveness associated with obtaining the bronchial brushes biopsies. Nasal epithelial cells are obtained through much less invasive superficial nasal scrape biopsies and subjects can be biopsied multiple times with no significant side effects. Additionally, the nose is the entry point to the respiratory system and therefore one of the first sites to be exposed to any kind of air-borne stressor, such as microbial agents, pollutants, or allergens. Briefly, nasal epithelial cells obtained from human volunteers are expanded on coated tissue culture plates, and then transferred onto cell culture inserts. Upon reaching confluency, cells continue to be cultured at the air-liquid interface (ALI), for several weeks, which creates more physiologically relevant conditions. The ALI culture condition uses defined media leading to a differentiated epithelium that exhibits morphological and functional characteristics similar to the human nasal epithelium, with both ciliated and mucus producing cells. Tissue culture inserts with differentiated nasal epithelial cells can be manipulated in a variety of ways depending on the research questions (treatment with pharmacological agents, transduction with lentiviral vectors, exposure to gases, or infection with microbial agents) and analyzed for numerous different endpoints ranging from cellular and molecular pathways, functional changes, morphology, etc. In vitro models of differentiated human nasal epithelial

  6. Culturing of human nasal epithelial cells at the air liquid interface.

    PubMed

    Müller, Loretta; Brighton, Luisa E; Carson, Johnny L; Fischer, William A; Jaspers, Ilona

    2013-10-08

    In vitro models using human primary epithelial cells are essential in understanding key functions of the respiratory epithelium in the context of microbial infections or inhaled agents. Direct comparisons of cells obtained from diseased populations allow us to characterize different phenotypes and dissect the underlying mechanisms mediating changes in epithelial cell function. Culturing epithelial cells from the human tracheobronchial region has been well documented, but is limited by the availability of human lung tissue or invasiveness associated with obtaining the bronchial brushes biopsies. Nasal epithelial cells are obtained through much less invasive superficial nasal scrape biopsies and subjects can be biopsied multiple times with no significant side effects. Additionally, the nose is the entry point to the respiratory system and therefore one of the first sites to be exposed to any kind of air-borne stressor, such as microbial agents, pollutants, or allergens. Briefly, nasal epithelial cells obtained from human volunteers are expanded on coated tissue culture plates, and then transferred onto cell culture inserts. Upon reaching confluency, cells continue to be cultured at the air-liquid interface (ALI), for several weeks, which creates more physiologically relevant conditions. The ALI culture condition uses defined media leading to a differentiated epithelium that exhibits morphological and functional characteristics similar to the human nasal epithelium, with both ciliated and mucus producing cells. Tissue culture inserts with differentiated nasal epithelial cells can be manipulated in a variety of ways depending on the research questions (treatment with pharmacological agents, transduction with lentiviral vectors, exposure to gases, or infection with microbial agents) and analyzed for numerous different endpoints ranging from cellular and molecular pathways, functional changes, morphology, etc. In vitro models of differentiated human nasal epithelial

  7. Monitoring of volatile and non-volatile urban air genotoxins using bacteria, human cells and plants.

    PubMed

    Ceretti, E; Zani, C; Zerbini, I; Viola, G; Moretti, M; Villarini, M; Dominici, L; Monarca, S; Feretti, D

    2015-02-01

    Urban air contains many mutagenic pollutants. This research aimed to investigate the presence of mutagens in the air by short-term mutagenicity tests using bacteria, human cells and plants. Inflorescences of Tradescantia were exposed to air in situ for 6h, once a month from January to May, to monitor volatile compounds and micronuclei frequency was computed. On the same days PM10 was collected continuously for 24h. Half of each filter was extracted with organic solvents and studied by means of the Ames test, using Salmonella typhimurium TA98 and TA100 strains, and the comet assay on human leukocytes. A quarter of each filter was extracted with distilled water in which Tradescantia was exposed. PM10 concentration was particularly high in the winter season (> 50 μg/m(3)). In situ exposure of inflorescences to urban air induced a significant increase in micronuclei frequency at all the sites considered, but only in January (p < 0.01). Aqueous extracts collected in January and February induced genotoxic effects in Tradescantia exposed in the laboratory (p < 0.01). Ames test showed that organic extracts of winter urban air were able to induce genetic mutations in S. typhimurium TA98 strain (± S9), but not in TA100 strain, with a revertants/plate number nine times higher than the negative control. Comet assay showed that winter extracts were more toxic and genotoxic than spring extracts. All the mutagenicity tests performed confirmed that urban air in North Italy in winter contains both volatile and non-volatile genotoxic substances able to induce genetic damage in bacteria, human cells and plants. PMID:25084136

  8. Fungal spore concentrations in two haematopoietic stem cell transplantation (HSCT) units containing distinct air control systems.

    PubMed

    Brun, C P; Miron, D; Silla, L M R; Pasqualotto, A C

    2013-04-01

    Invasive fungal diseases have emerged as important causes of morbidity and mortality in haematological patients. In this study air samples were collected in two haematopoietic stem cell transplantation (HSCT) units, in which distinct air-control systems were in place. In hospital 1 no high-efficiency particulate air (HEPA) filter was available whereas in hospital 2 HSCT rooms were equipped with HEPA filters, with positive air pressure in relation to the corridor. A total of 117 samples from rooms, toilets and corridors were obtained during December 2009 to January 2011, using a six-stage Andersen sampler. In both hospitals, the concentration of potentially pathogenic fungi in the air was reduced in patients' rooms compared to corridors (P < 0·0001). Despite the presence of a HEPA filter in hospital 2, rooms in both hospitals showed similar concentrations of potentially pathogenic fungi (P = 0·714). These findings may be explained by the implementation of additional protective measures in hospital 1, emphasizing the importance of such measures in protected environments. PMID:22691688

  9. Morphology control of zinc regeneration for zinc-air fuel cell and battery

    NASA Astrophysics Data System (ADS)

    Wang, Keliang; Pei, Pucheng; Ma, Ze; Xu, Huachi; Li, Pengcheng; Wang, Xizhong

    2014-12-01

    Morphology control is crucial both for zinc-air batteries and for zinc-air fuel cells during zinc regeneration. Zinc dendrite should be avoided in zinc-air batteries and zinc pellets are yearned to be formed for zinc-air fuel cells. This paper is mainly to analyze the mechanism of shape change and to control the zinc morphology during charge. A numerical three-dimensional model for zinc regeneration is established with COMSOL software on the basis of ionic transport theory and electrode reaction electrochemistry, and some experiments of zinc regeneration are carried out. The deposition process is qualitatively analyzed by the kinetics Monte Carlo method to study the morphological change from the electrocrystallization point of view. Morphological evolution of deposited zinc under different conditions of direct currents and pulse currents is also investigated by simulation. The simulation shows that parametric variables of the flowing electrolyte, the surface roughness and the structure of the electrode, the charging current and mode affect morphological evolution. The uniform morphology of deposited zinc is attained at low current, pulsating current or hydrodynamic electrolyte, and granular morphology is obtained by means of an electrode of discrete columnar structure in combination with high current and flowing electrolyte.

  10. Low cost stable air electrode material for high temperature solid oxide electrolyte electrochemical cells

    DOEpatents

    Kuo, Lewis J. H.; Singh, Prabhakar; Ruka, Roswell J.; Vasilow, Theodore R.; Bratton, Raymond J.

    1997-01-01

    A low cost, lanthanide-substituted, dimensionally and thermally stable, gas permeable, electrically conductive, porous ceramic air electrode composition of lanthanide-substituted doped lanthanum manganite is provided which is used as the cathode in high temperature, solid oxide electrolyte fuel cells and generators. The air electrode composition of this invention has a much lower fabrication cost as a result of using a lower cost lanthanide mixture, either a natural mixture or an unfinished lanthanide concentrate obtained from a natural mixture subjected to incomplete purification, as the raw material in place of part or all of the higher cost individual lanthanum. The mixed lanthanide primarily contains a mixture of at least La, Ce, Pr, and Nd, or at least La, Ce, Pr, Nd and Sm in its lanthanide content, but can also include minor amounts of other lanthanides and trace impurities. The use of lanthanides in place of some or all of the lanthanum also increases the dimensional stability of the air electrode. This low cost air electrode can be fabricated as a cathode for use in high temperature, solid oxide fuel cells and generators.

  11. Low cost stable air electrode material for high temperature solid oxide electrolyte electrochemical cells

    DOEpatents

    Kuo, L.J.H.; Singh, P.; Ruka, R.J.; Vasilow, T.R.; Bratton, R.J.

    1997-11-11

    A low cost, lanthanide-substituted, dimensionally and thermally stable, gas permeable, electrically conductive, porous ceramic air electrode composition of lanthanide-substituted doped lanthanum manganite is provided which is used as the cathode in high temperature, solid oxide electrolyte fuel cells and generators. The air electrode composition of this invention has a much lower fabrication cost as a result of using a lower cost lanthanide mixture, either a natural mixture or an unfinished lanthanide concentrate obtained from a natural mixture subjected to incomplete purification, as the raw material in place of part or all of the higher cost individual lanthanum. The mixed lanthanide primarily contains a mixture of at least La, Ce, Pr, and Nd, or at least La, Ce, Pr, Nd and Sm in its lanthanide content, but can also include minor amounts of other lanthanides and trace impurities. The use of lanthanides in place of some or all of the lanthanum also increases the dimensional stability of the air electrode. This low cost air electrode can be fabricated as a cathode for use in high temperature, solid oxide fuel cells and generators. 4 figs.

  12. Effects of air transient spark discharge and helium plasma jet on water, bacteria, cells, and biomolecules.

    PubMed

    Hensel, Karol; Kučerová, Katarína; Tarabová, Barbora; Janda, Mário; Machala, Zdenko; Sano, Kaori; Mihai, Cosmin Teodor; Ciorpac, Mitică; Gorgan, Lucian Dragos; Jijie, Roxana; Pohoata, Valentin; Topala, Ionut

    2015-06-06

    Atmospheric pressure DC-driven self-pulsing transient spark (TS) discharge operated in air and pulse-driven dielectric barrier discharge plasma jet (PJ) operated in helium in contact with water solutions were used for inducing chemical effects in water solutions, and the treatment of bacteria (Escherichia coli), mammalian cells (Vero line normal cells, HeLa line cancerous cells), deoxyribonucleic acid (dsDNA), and protein (bovine serum albumin). Two different methods of water solution supply were used in the TS: water electrode system and water spray system. The effects of both TS systems and the PJ were compared, as well as a direct exposure of the solution to the discharge with an indirect exposure to the discharge activated gas flow. The chemical analysis of water solutions was performed by using colorimetric methods of UV-VIS absorption spectrophotometry. The bactericidal effects of the discharges on bacteria were evaluated by standard microbiological plate count method. Viability, apoptosis and cell cycle were assessed in normal and cancerous cells. Viability of cells was evaluated by trypan blue exclusion test, apoptosis by Annexin V-FITC/propidium iodide assay, and cell cycle progression by propidium iodide/RNase test. The effect of the discharges on deoxyribonucleic acid and protein were evaluated by fluorescence and UV absorption spectroscopy. The results of bacterial and mammalian cell viability, apoptosis, and cell cycle clearly show that cold plasma can inactivate bacteria and selectively target cancerous cells, which is very important for possible future development of new plasma therapeutic strategies in biomedicine. The authors found that all investigated bio-effects were stronger with the air TS discharge than with the He PJ, even in indirect exposure.

  13. Modelling the effects of microgravity on the permeability of air interface respiratory epithelial cell layers

    NASA Astrophysics Data System (ADS)

    dos Santos, Marlise A.; Bosquillon, Cynthia; Russomano, Thais; Sundaresan, Alamelu; Falcão, Felipe; Marriott, Christopher; Forbes, Ben

    2010-09-01

    Although it has been suggested that microgravity might affect drug absorption in vivo, drug permeability across epithelial barriers has not yet been investigated in vitro during modelled microgravity. Therefore, a cell culture/diffusion chamber was designed specifically to accommodate epithelial cell layers in a 3D-clinostat and allow epithelial permeability to be measured under microgravity conditions in vitro with minimum alteration to established cell culture techniques. Human respiratory epithelial Calu-3 cell layers were used to model the airway epithelium. Cells grown at an air interface in the diffusion chamber from day 1 or day 5 after seeding on 24-well polyester Transwell cell culture inserts developed a similar transepithelial electrical resistance (TER) to cells cultured in conventional cell culture plates. Confluent Calu-3 layers exposed to modelled microgravity in the 3D-clinostat for up to 48 h maintained their high TER. The permeability of the paracellular marker 14C-mannitol was unaffected after a 24 h rotation of the cell layers in the 3D-clinostat, but was increased 2-fold after 48 h of modelled microgravity. It was demonstrated that the culture/diffusion chamber developed is suitable for culturing epithelial cell layers and, when subjected to rotation in the 3D-clinostat, will be a valuable in vitro system in which to study the influence of microgravity on epithelial permeability and drug transport.

  14. Aire-dependent thymic development of tumor-associated regulatory T cells.

    PubMed

    Malchow, Sven; Leventhal, Daniel S; Nishi, Saki; Fischer, Benjamin I; Shen, Lynn; Paner, Gladell P; Amit, Ayelet S; Kang, Chulho; Geddes, Jenna E; Allison, James P; Socci, Nicholas D; Savage, Peter A

    2013-03-01

    Despite considerable interest in the modulation of tumor-associated Foxp3(+) regulatory T cells (T(regs)) for therapeutic benefit, little is known about the developmental origins of these cells and the nature of the antigens that they recognize. We identified an endogenous population of antigen-specific T(regs) (termed MJ23 T(regs)) found recurrently enriched in the tumors of mice with oncogene-driven prostate cancer. MJ23 T(regs) were not reactive to a tumor-specific antigen but instead recognized a prostate-associated antigen that was present in tumor-free mice. MJ23 T(regs) underwent autoimmune regulator (Aire)-dependent thymic development in both male and female mice. Thus, Aire-mediated expression of peripheral tissue antigens drives the thymic development of a subset of organ-specific T(regs), which are likely coopted by tumors developing within the associated organ.

  15. Aire-dependent thymic development of tumor-associated regulatory T cells*

    PubMed Central

    Malchow, Sven; Leventhal, Daniel S.; Nishi, Saki; Fischer, Benjamin I.; Shen, Lynn; Paner, Gladell P.; Amit, Ayelet S.; Kang, Chulho; Geddes, Jenna E.; Allison, James P.; Socci, Nicholas D.; Savage, Peter A.

    2013-01-01

    Despite considerable interest in the modulation of tumor-associated Foxp3+ regulatory T cells (Tregs) for therapeutic benefit, little is known about the developmental origins of these cells and the nature of the antigens that they recognize. Here, we identified an endogenous population of antigen-specific Tregs (termed “MJ23” Tregs) found recurrently enriched in the tumors of mice with oncogene-driven prostate cancer. MJ23 Tregs were not reactive to a tumor-specific antigen, but instead recognized a prostate-associated antigen that was present in tumor-free mice. MJ23 Tregs underwent Aire-dependent thymic development in both male and female mice. Thus Aire-mediated expression of peripheral tissue antigens drives the thymic development of a subset of organ-specific Tregs, which are likely co-opted by tumors developing within the associated organ. PMID:23471412

  16. Genotoxicity to human cells induced by air particulates isolated during the Kuwait oil fires.

    PubMed

    Kelsey, K T; Xia, F; Bodell, W J; Spengler, J D; Christiani, D C; Dockery, D W; Liber, H L

    1994-01-01

    In an effort to examine the potential of exposure to soot from the 1991 oil fires in the Kuwait desert for inducing genetic effects we studied the in vitro genotoxicity of this material. Air particulates isolated near the Kuwait oil fires were studied using three assays. Dose-dependent increases were observed for both sister chromatid exchanges in human peripheral blood lymphocytes and mutation at the hprt locus in the metabolically competent human lymphoblast cell line AHH-1. Similar magnitudes of response were seen using these two assays when testing a standard air particulate sample which had been isolated from the Washington, DC, area. Using the 32P-postlabeling assay, no increase in DNA adduct formation was observed in AHH-1 cells treated with particulates isolated from sampling in Kuwait.

  17. Experimental investigation on a turbine compressor for air supply system of a fuel cell

    SciTech Connect

    Matsuda, Masayasu; Tsuchiyama, Syozo

    1996-12-31

    This report covers part of a joint study on a PEFC propulsion system for surface ships, summarized in a presentation to this Seminar, entitled {open_quotes}Study on a Polymer Electrolyte Fuel Cell (PEFC) Propulsion System for Surface Ships{close_quotes}, and which envisages application to a 1,500 DWT cargo vessel. The aspect treated here concerns a study on the air supply system for the PEFC, with particular reference to system components.

  18. Seeking effective dyes for a mediated glucose-air alkaline battery/fuel cell

    NASA Astrophysics Data System (ADS)

    Eustis, Ross; Tsang, Tsz Ming; Yang, Brigham; Scott, Daniel; Liaw, Bor Yann

    2014-02-01

    A significant level of power generation from an abiotic, air breathing, mediated reducing sugar-air alkaline battery/fuel cell has been achieved in our laboratories at room temperature without complicated catalysis or membrane separation in the reaction chamber. Our prior studies suggested that mass transport limitation by the mediator is a limiting factor in power generation. New and effective mediators were sought here to improve charge transfer and power density. Forty-five redox dyes were studied to identify if any can facilitate mass transport in alkaline electrolyte solution; namely, by increasing the solubility and mobility of the dye, and the valence charge carried per molecule. Indigo dyes were studied more closely to understand the complexity involved in mass transport. The viability of water-miscible co-solvents was also explored to understand their effect on solubility and mass transport of the dyes. Using a 2.0 mL solution, 20% methanol by volume, with 100 mM indigo carmine, 1.0 M glucose and 2.5 M sodium hydroxide, the glucose-air alkaline battery/fuel cell attained 8 mA cm-2 at short-circuit and 800 μW cm-2 at the maximum power point. This work shall aid future optimization of mediated charge transfer mechanism in batteries or fuel cells.

  19. Hydroponics gel as a new electrolyte gelling agent for alkaline zinc-air cells

    NASA Astrophysics Data System (ADS)

    Othman, R.; Basirun, W. J.; Yahaya, A. H.; Arof, A. K.

    The viability of hydroponics gel as a new alkaline electrolyte gelling agent is investigated. Zinc-air cells are fabricated employing 12 wt.% KOH electrolyte immobilised with hydroponics gel. The cells are discharged at constant currents of 5, 50 and 100 mA. XRD and SEM analysis of the anode plates after discharge show that the failure mode is due to the formation of zinc oxide insulating layers and not due to any side reactions between the gel and the plate or the electrolyte.

  20. Initial testing of two DEMI (Driesbach Electromotive Inc. ) Model 4E zinc-air rechargeable cells

    SciTech Connect

    Hardin, J.E.; Martin, M.E.

    1989-10-23

    The purpose of this document is to report the results of INEL laboratory testing of two DEMI 4E Aerobic Power Battery Cells (collectively designated Pack 46 in INEL records). The 4E Aerobic Power Battery is a secondary battery developed privately by Driesbach Electromotive Inc. (DEMI). The battery employs zinc as the anode and a bifunctional air cathode. This testing was performed as the first phase of a cooperative agreement between INEL and DEMI leading to the construction and testing of electric vehicle-size cells, to be followed eventually by a battery pack. 3 refs., 3 figs., 5 tabs.

  1. Responses of differentiated primary human lung epithelial cells to exposure to diesel exhaust at an air-liquid interface.

    PubMed

    Seagrave, JeanClare; Dunaway, Sandy; McDonald, Jacob D; Mauderly, Joe L; Hayden, Patrick; Stidley, Christine

    2007-01-01

    In vitro responses of potential target cell types to air pollutants under physiological conditions may be useful in understanding the health effects of air pollution exposure. The study evaluated responses of human primary airway epithelial cells to diesel exhaust (DE). Cultures of cells from 3 donors, differentiated by culture on membranes with the apical surfaces exposed to the atmosphere, were exposed to filtered air or DE. Some exposure-related effects were similar among donors, whereas others were affected by the donor, consistent with human population heterogeneity. This model may be useful for mechanistic and comparative toxicology studies. PMID:17364910

  2. From the Field to the Laboratory: Air Pollutant-Induced Genomic Effects in Lung Cells

    PubMed Central

    Vizuete, William; Sexton, Kenneth G.; Nguyen, Hang; Smeester, Lisa; Aagaard, Kjersti Marie; Shope, Cynthia; Lefer, Barry; Flynn, James H.; Alvarez, Sergio; Erickson, Mathew H.; Fry, Rebecca C.

    2015-01-01

    Current in vitro studies do not typically assess cellular impacts in relation to real-world atmospheric mixtures of gases. In this study, we set out to examine the feasibility of measuring biological responses at the level of gene expression in human lung cells upon direct exposures to air in the field. This study describes the successful deployment of lung cells in the heavily industrialized Houston Ship Channel. By examining messenger RNA (mRNA) levels from exposed lung cells, we identified changes in genes that play a role as inflammatory responders in the cell. The results show anticipated responses from negative and positive controls, confirming the integrity of the experimental protocol and the successful deployment of the in vitro instrument. Furthermore, exposures to ambient conditions displayed robust changes in gene expression. These results demonstrate a methodology that can produce gas-phase toxicity data in the field. PMID:26917966

  3. Zinc air refuelable battery: alternative zinc fuel morphologies and cell behavior

    SciTech Connect

    Cooper, J.F.; Krueger, R.

    1997-01-01

    Multicell zinc/air batteries have been tested previously in the laboratory and as part of the propulsion system of an electric bus; cut zinc wire was used as the anode material. This battery is refueled by a hydraulic transport of 0.5-1 mm zinc particles into hoppers above each cell. We report an investigation concerning alternative zinc fuel morphologies, and energy losses associated with refueling and with overnight or prolonged standby. Three types of fuel pellets were fabricated, tested and compared with results for cut wire: spheres produced in a fluidized bed electrolysis cell; elongated particles produced by gas-atomization; and pellets produced by chopping 1 mm porous plates made of compacted zinc fines. Relative sizes of the particles and cell gap dimensions are critical. All three types transported within the cell 1553 and showed acceptable discharge characteristics, but a fluidized bed approach appears especially attractive for owner/user recovery operations.

  4. Epithelial cells, the “switchboard” of respiratory immune defense responses: effects of air pollutants

    PubMed Central

    Müller, Loretta; Jaspers, Ilona

    2015-01-01

    Summary “Epimmunome”, a term introduced recently by Swamy and colleagues, describes all molecules and pathways used by epithelial cells (ECs) to instruct immune cells. Today, we know that ECs are among the first sites within the human body to be exposed to pathogens (such as influenza viruses) and that the release of chemokine and cytokines by ECs is influenced by inhaled agents. The role of the ECs as a switchboard to initiate and regulate immune responses is altered through air pollutant exposure, such as ozone, tobacco smoke and diesel exhaust emissions. The details of the interplay between ECs and immune cells are not yet fully understood and need to be investigated further. Co-culture models, cell specific genetically-modified mice and the analysis of human biopsies provide great tools to gain knowledge about potential mechanisms. Increasing our understanding about the role of ECs in respiratory immunity may yield novel therapeutic targets to modulate downstream diseases. PMID:22851042

  5. From the Field to the Laboratory: Air Pollutant-Induced Genomic Effects in Lung Cells.

    PubMed

    Vizuete, William; Sexton, Kenneth G; Nguyen, Hang; Smeester, Lisa; Aagaard, Kjersti Marie; Shope, Cynthia; Lefer, Barry; Flynn, James H; Alvarez, Sergio; Erickson, Mathew H; Fry, Rebecca C

    2015-01-01

    Current in vitro studies do not typically assess cellular impacts in relation to real-world atmospheric mixtures of gases. In this study, we set out to examine the feasibility of measuring biological responses at the level of gene expression in human lung cells upon direct exposures to air in the field. This study describes the successful deployment of lung cells in the heavily industrialized Houston Ship Channel. By examining messenger RNA (mRNA) levels from exposed lung cells, we identified changes in genes that play a role as inflammatory responders in the cell. The results show anticipated responses from negative and positive controls, confirming the integrity of the experimental protocol and the successful deployment of the in vitro instrument. Furthermore, exposures to ambient conditions displayed robust changes in gene expression. These results demonstrate a methodology that can produce gas-phase toxicity data in the field.

  6. Disruption of spindle checkpoint function ahead of facilitation of cell proliferation by repeated administration of hepatocarcinogens in rats.

    PubMed

    Kimura, Masayuki; Mizukami, Sayaka; Watanabe, Yousuke; Hasegawa-Baba, Yasuko; Onda, Nobuhiko; Yoshida, Toshinori; Shibutani, Makoto

    2015-12-01

    We aimed to clarify the hepatocarcinogen-specific disruption of cell cycle checkpoint functions and its time course after repeated administration of hepatocarcinogens. Thus, rats were repeatedly administered with hepatocarcinogens (methapyrilene, carbadox and thioacetamide), a marginal hepatocarcinogen (leucomalachite green), hepatocarcinogenic promoters (oxfendazole and β-naphthoflavone) or non-carcinogenic hepatotoxicants (promethazine and acetaminophen) for 7, 28 or 90 days, and the temporal changes in cell proliferation, expression of G1/S and spindle checkpoint-related molecules, and apoptosis were examined using immunohistochemistry and/or real-time RT-PCR analysis. Hepatocarcinogens facilitating cell proliferation at day 28 of administration also facilitated cell proliferation and apoptosis at day 90. Hepatocarcinogen- or hepatocarcinogenic promoter-specific cellular responses were not detected by immunohistochemical single molecule analysis even after 90 days. Expression of Cdkn1a, Mad2l1, Chek1 and Rbl2 mRNA also lacked specificity to hepatocarcinogens or hepatocarcinogenic promoters. In contrast, all hepatocarcinogens and the marginally hepatocarcinogenic leucomalachite green induced Mdm2 upregulation or increase in the number of phosphorylated MDM2(+) cells from day 28, irrespective of the lack of cell proliferation facilitation by some compounds. However, different Tp53 expression levels suggest different mechanisms of induction or activation of MDM2 among hepatocarcinogens. On the other hand, hepatocarcinogenic methapyrilene and carbadox downregulated the number of both ubiquitin D(+) cells and proliferating cells remaining in M phase at day 28 and/or day 90, irrespective of the lack of cell proliferation facilitation in the latter. These results suggest that hepatocarcinogens disrupt spindle checkpoint function after 28 or 90 days of administration, which may be induced ahead of cell proliferation facilitation. PMID:26558467

  7. Disruption of spindle checkpoint function ahead of facilitation of cell proliferation by repeated administration of hepatocarcinogens in rats.

    PubMed

    Kimura, Masayuki; Mizukami, Sayaka; Watanabe, Yousuke; Hasegawa-Baba, Yasuko; Onda, Nobuhiko; Yoshida, Toshinori; Shibutani, Makoto

    2015-12-01

    We aimed to clarify the hepatocarcinogen-specific disruption of cell cycle checkpoint functions and its time course after repeated administration of hepatocarcinogens. Thus, rats were repeatedly administered with hepatocarcinogens (methapyrilene, carbadox and thioacetamide), a marginal hepatocarcinogen (leucomalachite green), hepatocarcinogenic promoters (oxfendazole and β-naphthoflavone) or non-carcinogenic hepatotoxicants (promethazine and acetaminophen) for 7, 28 or 90 days, and the temporal changes in cell proliferation, expression of G1/S and spindle checkpoint-related molecules, and apoptosis were examined using immunohistochemistry and/or real-time RT-PCR analysis. Hepatocarcinogens facilitating cell proliferation at day 28 of administration also facilitated cell proliferation and apoptosis at day 90. Hepatocarcinogen- or hepatocarcinogenic promoter-specific cellular responses were not detected by immunohistochemical single molecule analysis even after 90 days. Expression of Cdkn1a, Mad2l1, Chek1 and Rbl2 mRNA also lacked specificity to hepatocarcinogens or hepatocarcinogenic promoters. In contrast, all hepatocarcinogens and the marginally hepatocarcinogenic leucomalachite green induced Mdm2 upregulation or increase in the number of phosphorylated MDM2(+) cells from day 28, irrespective of the lack of cell proliferation facilitation by some compounds. However, different Tp53 expression levels suggest different mechanisms of induction or activation of MDM2 among hepatocarcinogens. On the other hand, hepatocarcinogenic methapyrilene and carbadox downregulated the number of both ubiquitin D(+) cells and proliferating cells remaining in M phase at day 28 and/or day 90, irrespective of the lack of cell proliferation facilitation in the latter. These results suggest that hepatocarcinogens disrupt spindle checkpoint function after 28 or 90 days of administration, which may be induced ahead of cell proliferation facilitation.

  8. Selective capacity of metreleptin administration to reconstitute CD4+ T-cell number in females with acquired hypoleptinemia.

    PubMed

    Matarese, Giuseppe; La Rocca, Claudia; Moon, Hyun-Seuk; Huh, Joo Young; Brinkoetter, Mary T; Chou, Sharon; Perna, Francesco; Greco, Dario; Kilim, Holly P; Gao, Chuanyun; Arampatzi, Kalliope; Wang, Zhaoxi; Mantzoros, Christos S

    2013-02-26

    Leptin is an adipocyte-derived hormone that controls food intake and reproductive and immune functions in rodents. In uncontrolled human studies, low leptin levels are associated with impaired immune responses and reduced T-cell counts; however, the effects of leptin replacement on the adaptive immune system have not yet been reported in the context of randomized, controlled studies and/or in conditions of chronic acquired leptin deficiency. To address these questions, we performed a randomized, double-blinded, placebo-controlled trial of recombinant methionyl-human leptin (metreleptin) administration in replacement doses in women experiencing the female triad (hypothalamic amenorrhea) with acquired chronic hypoleptinemia induced by negative energy balance. Metreleptin restored both CD4(+) T-cell counts and their in vitro proliferative responses in these women. These changes were accompanied by a transcriptional signature in which genes relevant to cell survival and hormonal response were up-regulated, and apoptosis genes were down-regulated in circulating immune cells. We also observed that signaling pathways involved in cell growth/survival/proliferation, such as the STAT3, AMPK, mTOR, ERK1/2, and Akt pathways, were activated directly by acute in vivo metreleptin administration in peripheral blood mononuclear cells and CD4(+) T-cells both from subjects with chronic hypoleptinemia and from normoleptinemic, lean female subjects. Our data show that metreleptin administration, in doses that normalize circulating leptin levels, induces transcriptional changes, activates intracellular signaling pathways, and restores CD4(+) T-cell counts. Thus, metreleptin may prove to be a safe and effective therapy for selective CD4(+) T-cell immune reconstitution in hypoleptinemic states such as tuberculosis and HIV infection in which CD4(+) T cells are reduced.

  9. Pulmonary T cell activation in response to chronic particulate air pollution

    PubMed Central

    Deiuliis, Jeffrey A.; Kampfrath, Thomas; Zhong, Jixin; Oghumu, Steve; Maiseyeu, Andrei; Chen, Lung Chi; Sun, Qinghua; Satoskar, Abhay R.

    2012-01-01

    The purpose of this study was to investigate the effects of chronically inhaled particulate matter <2.5 μm (PM2.5) on inflammatory cell populations in the lung and systemic circulation. A prominent component of air pollution exposure is a systemic inflammatory response that may exaggerate chronic diseases such as atherosclerosis and insulin resistance. T cell response was measured in wild-type C57B/L6, Foxp3-green fluorescent protein (GFP) “knockin,” and chemokine receptor 3 knockout (CXCR3−/−) mice following 24–28 wk of PM2.5 or filtered air. Chronic PM2.5 exposure resulted in increased CXCR3-expressing CD4+ and CD8+ T cells in the lungs, spleen, and blood with elevation in CD11c+ macrophages in the lung and oxidized derivatives of 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphorylcholine in wild-type mice. CXCR3 deficiency decreased T cells in the lung. GFP+ regulatory T cells increased with PM2.5 exposure in the spleen and blood of Foxp3-GFP mice but were present at very low levels in the lung irrespective of PM2.5 exposure. Mixed lymphocyte cultures using primary, PM2.5-treated macrophages demonstrated enhanced T cell proliferation. Our experiments indicate that PM2.5 potentiates a proinflammatory Th1 response involving increased homing of CXCR3+ T effector cells to the lung and modulation of systemic T cell populations. PMID:22160305

  10. Xanthosine administration does not affect the proportion of epithelial stem cells in bovine mammary tissue, but has a latent negative effect on cell proliferation

    SciTech Connect

    Rauner, Gat; Barash, Itamar

    2014-10-15

    The challenge in manipulating the proportion of somatic stem cells lies in having to override tissue homeostasis. Xanthosine infusion via the teat canal has been reported to augment the number of label-retaining cells in the mammary gland of 3-month-old bovine calves. To further delineate xanthosine's effect on defined stem cells in the mammary gland of heifers—which are candidates for increased prospective milk production following such manipulation—bovine mammary parenchymal tissue was transplanted and integrated into the cleared mammary fat pad of immunodeficient mice. Xanthosine administration for 14 days did not affect the number of label-retaining cells after 10- and 11-week chases. No change in stem cell proportion, analyzed according to CD49f and CD24 expression, was noted. Clone formation and propagation rate of cultured cells, as well as expression of stem cell markers, were also unaffected. In contrast, a latent 50% decrease in bovine mammary cell proliferation rate was observed 11 weeks after xanthosine administration. Tumor development in mice was also limited by xanthosine administration. These effects may have resulted from an initial decrease in expression of the rate-limiting enzyme in guanine synthesis, IMPDH. The data indicate that caution should be exerted when considering xanthosine for stem cell manipulation. - Highlights: • Novel “bovinized“ mouse model for exogenous effects on bovine mammary gland. • Xanthosine did not affect stem cell number/function in bovine mammary gland. • Xanthosine caused an immediate decrease in IMPDH expression in bovine mammary gland. • Xanthosine had latent negative effect on cell proliferation in bovine mammary gland. • Xanthosine administration limited mammary tumor growth.

  11. The Thymic Orchestration Involving Aire, miRNAs, and Cell-Cell Interactions during the Induction of Central Tolerance.

    PubMed

    Passos, Geraldo Aleixo; Mendes-da-Cruz, Daniella Arêas; Oliveira, Ernna Hérida

    2015-01-01

    Developing thymocytes interact sequentially with two distinct structures within the thymus: the cortex and medulla. Surviving single-positive and double-positive thymocytes from the cortex migrate into the medulla, where they interact with medullary thymic epithelial cells (mTECs). These cells ectopically express a vast set of peripheral tissue antigens (PTAs), a property termed promiscuous gene expression that is associated with the presentation of PTAs by mTECs to thymocytes. Thymocyte clones that have a high affinity for PTAs are eliminated by apoptosis in a process termed negative selection, which is essential for tolerance induction. The Aire gene is an important factor that controls the expression of a large set of PTAs. In addition to PTAs, Aire also controls the expression of miRNAs in mTECs. These miRNAs are important in the organization of the thymic architecture and act as posttranscriptional controllers of PTAs. Herein, we discuss recent discoveries and highlight open questions regarding the migration and interaction of developing thymocytes with thymic stroma, the ectopic expression of PTAs by mTECs, the association between Aire and miRNAs and its effects on central tolerance.

  12. Lanthanum manganite-based air electrode for solid oxide fuel cells

    DOEpatents

    Ruka, Roswell J.; Kuo, Lewis; Li, Baozhen

    1999-01-01

    An air electrode material for a solid oxide fuel cell is disclosed. The electrode material is based on lanthanum manganite having a perovskite-like crystal structure ABO.sub.3. The A-site of the air electrode material preferably comprises La, Ca, Ce and at least one lanthanide selected from Sm, Gd, Dy, Er, Y and Nd. The B-site of the electrode material comprises Mn with substantially no dopants. The ratio of A:B is preferably slightly above 1. A preferred air electrode composition is of the formula La.sub.w Ca.sub.x Ln.sub.y Ce.sub.z MnO.sub.3, wherein Ln comprises at least one lanthanide selected from Sm, Gd, Dy, Er, Y and Nd, w is from about 0.55 to about 0.56, x is from about 0.255 to about 0.265, y is from about 0.175 to about 0.185, and z is from about 0.005 to about 0.02. The air electrode material possesses advantageous chemical and electrical properties as well as favorable thermal expansion and thermal cycle shrinkage characteristics.

  13. Lanthanum manganite-based air electrode for solid oxide fuel cells

    DOEpatents

    Ruka, R.J.; Kuo, L.; Li, B.

    1999-06-29

    An air electrode material for a solid oxide fuel cell is disclosed. The electrode material is based on lanthanum manganite having a perovskite-like crystal structure ABO[sub 3]. The A-site of the air electrode material preferably comprises La, Ca, Ce and at least one lanthanide selected from Sm, Gd, Dy, Er, Y and Nd. The B-site of the electrode material comprises Mn with substantially no dopants. The ratio of A:B is preferably slightly above 1. A preferred air electrode composition is of the formula La[sub w]Ca[sub x]Ln[sub y]Ce[sub z]MnO[sub 3], wherein Ln comprises at least one lanthanide selected from Sm, Gd, Dy, Er, Y and Nd, w is from about 0.55 to about 0.56, x is from about 0.255 to about 0.265, y is from about 0.175 to about 0.185, and z is from about 0.005 to about 0.02. The air electrode material possesses advantageous chemical and electrical properties as well as favorable thermal expansion and thermal cycle shrinkage characteristics. 10 figs.

  14. Dual role of macrophages in the response of C26 colon carcinoma cells to 5-fluorouracil administration

    PubMed Central

    Patras, Laura; Sesarman, Alina; Licarete, Emilia; Luca, Lavinia; Alupei, Marius Costel; Rakosy-Tican, Elena; Banciu, Manuela

    2016-01-01

    Previous studies have demonstrated that tumor-associated macrophages (TAMs) are pivotal players in tumor progression via modulation of tumor angiogenesis, inflammation, metastasis and oxidative stress, as well as of the response of cancer cells to cytotoxic drugs. Nevertheless, the role of TAMs in the prognosis of colorectal cancer remains controversial. Therefore, the present study aimed to investigate how TAMs mediate the response of C26 colon carcinoma cells to the cytotoxic drug 5-fluorouracil (5-FU), upon TAM co-cultivation with these cancer cells in vitro. In this respect, 5-FU cytotoxicity was assessed in C26 cells in standard culture and in a co-culture with peritoneal macrophages, the production of NF-κB was determined by western blot analysis, and the production of angiogenic/inflammatory proteins in each experimental model was evaluated by protein array analysis. To gain further evidence of the effect of TAMs on oxidative stress, malondialdehyde was measured through high-performance liquid chromatography, and the total nonenzymatic antioxidant levels and the production of nitrites were measured through colorimetric assays. The results demonstrated that TAMs exerted a dual role in the response of C26 cells to 5-FU administration in the co-culture model. Thus, on one side, TAMs sensitized C26 cells to 5-FU administration through inhibition of the production of inflammatory and angiogenic proteins in these cancer cells; however, they also protected cancer cells against 5-FU-induced oxidative stress. Collectively, the present findings suggest that the combined administration of 5-FU with pharmacological agents that prevent TAMs to maintain the physiological range of tumor cell oxidative stress may highly improve the therapeutic potential of this drug. PMID:27446416

  15. Capacitive micromachined ultrasonic transducers based on annular cell geometry for air-coupled applications.

    PubMed

    Na, Shuai; Chen, Albert I H; Wong, Lawrence L P; Li, Zhenhao; Macecek, Mirek; Yeow, John T W

    2016-09-01

    A novel design of an air-coupled capacitive micromachined ultrasonic transducer (CMUT) with annular cell geometry (annular CMUT) is proposed. Finite element analysis shows that an annular cell has a ratio of average-to-maximum displacement (RAMD) of 0.52-0.58 which is 58-76% higher than that of a conventional circular cell. The increased RAMD leads to a larger volume displacement which results in a 48.4% improved transmit sensitivity and 127.3% improved power intensity. Single-cell annular CMUTs were fabricated with 20-μm silicon plates on 13.7-μm deep and 1.35-mm wide annular cavities using the wafer bonding technique. The measured RAMD of the fabricated CMUTs is 0.54. The resonance frequency was measured to be 94.5kHz at 170-V DC bias. The transmit sensitivity was measured to be 33.83Pa/V and 25.85Pa/V when the CMUT was excited by a continuous wave and a 20-cycle burst, respectively. The receive sensitivity at 170-V DC bias was measured to be 7.7mV/Pa for a 20-cycle burst, and 15.0mV/Pa for a continuous incident wave. The proposed annular CMUT design demonstrates a significant improvement in transmit efficiency, which is an important parameter for air-coupled ultrasonic transducers. PMID:27352025

  16. Efficient and stable perovskite solar cells prepared in ambient air irrespective of the humidity

    PubMed Central

    Tai, Qidong; You, Peng; Sang, Hongqian; Liu, Zhike; Hu, Chenglong; Chan, Helen L. W.; Yan, Feng

    2016-01-01

    Poor stability of organic–inorganic halide perovskite materials in humid condition has hindered the success of perovskite solar cells in real applications since controlled atmosphere is required for device fabrication and operation, and there is a lack of effective solutions to this problem until now. Here we report the use of lead (II) thiocyanate (Pb(SCN)2) precursor in preparing perovskite solar cells in ambient air. High-quality CH3NH3PbI3−x(SCN)x perovskite films can be readily prepared even when the relative humidity exceeds 70%. Under optimized processing conditions, we obtain devices with an average power conversion efficiency of 13.49% and the maximum efficiency over 15%. In comparison with typical CH3NH3PbI3-based devices, these solar cells without encapsulation show greatly improved stability in humid air, which is attributed to the incorporation of thiocyanate ions in the crystal lattice. The findings pave a way for realizing efficient and stable perovskite solar cells in ambient atmosphere. PMID:27033249

  17. Efficient and stable perovskite solar cells prepared in ambient air irrespective of the humidity

    NASA Astrophysics Data System (ADS)

    Tai, Qidong; You, Peng; Sang, Hongqian; Liu, Zhike; Hu, Chenglong; Chan, Helen L. W.; Yan, Feng

    2016-04-01

    Poor stability of organic-inorganic halide perovskite materials in humid condition has hindered the success of perovskite solar cells in real applications since controlled atmosphere is required for device fabrication and operation, and there is a lack of effective solutions to this problem until now. Here we report the use of lead (II) thiocyanate (Pb(SCN)2) precursor in preparing perovskite solar cells in ambient air. High-quality CH3NH3PbI3-x(SCN)x perovskite films can be readily prepared even when the relative humidity exceeds 70%. Under optimized processing conditions, we obtain devices with an average power conversion efficiency of 13.49% and the maximum efficiency over 15%. In comparison with typical CH3NH3PbI3-based devices, these solar cells without encapsulation show greatly improved stability in humid air, which is attributed to the incorporation of thiocyanate ions in the crystal lattice. The findings pave a way for realizing efficient and stable perovskite solar cells in ambient atmosphere.

  18. Potentially Pathogenic Bacteria in Shower Water and Air of a Stem Cell Transplant Unit▿

    PubMed Central

    Perkins, Sarah D.; Mayfield, Jennie; Fraser, Victoria; Angenent, Largus T.

    2009-01-01

    Potential pathogens from shower water and aerosolized shower mist (i.e., shower aerosol) have been suggested as an environmental source of infection for immunocompromised patients. To quantify the microbial load in shower water and aerosol samples, we used culture, microscopic, and quantitative PCR methods to investigate four shower stalls in a stem cell transplant unit at Barnes-Jewish Hospital in St. Louis, MO. We also tested membrane-integrated showerheads as a possible mitigation strategy. In addition to quantification, a 16S rRNA gene sequencing survey was used to characterize the abundant bacterial populations within shower water and aerosols. The average total bacterial counts were 2.2 × 107 cells/liter in shower water and 3.4 × 104 cells/m3 in shower aerosol, and these counts were reduced to 6.3 × 104 cells/liter (99.6% efficiency) and 8.9 × 103 cells/m3 (82.4% efficiency), respectively, after membrane-integrated showerheads were installed. Potentially pathogenic organisms were found in both water and aerosol samples from the conventional showers. Most notable was the presence of Mycobacterium mucogenicum (99.5% identity) in the water and Pseudomonas aeruginosa (99.3% identity) in the aerosol samples. Membrane-integrated showerheads may protect immunocompromised patients from waterborne infections in a stem cell transplant unit because of efficient capture of vast numbers of potentially pathogenic bacteria from hospital water. However, an in-depth epidemiological study is necessary to investigate whether membrane-integrated showerheads reduce hospital-acquired infections. The microbial load in shower aerosols with conventional showerheads was elevated compared to the load in HEPA-filtered background air in the stem cell unit, but it was considerably lower than typical indoor air. Thus, in shower environments without HEPA filtration, the increase in microbial load due to shower water aerosolization would not have been distinguishable from anticipated

  19. Passive cathodic water/air management device for micro-direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Peng, Hsien-Chih; Chen, Po-Hon; Chen, Hung-Wen; Chieng, Ching-Chang; Yeh, Tsung-Kuang; Pan, Chin; Tseng, Fan-Gang

    A high efficient passive water/air management device (WAMD) is proposed and successfully demonstrated in this paper. The apparatus consists of cornered micro-channels and air-breathing windows with hydrophobicity arrangement to regulate liquids and gases to flow on their predetermined pathways. A high performance water/air separation with water removal rate of about 5.1 μl s -1 cm -2 is demonstrated. The performance of the proposed WAMD is sufficient to manage a cathode-generated water flux of 0.26 μl s -1 cm -2 in the micro-direct methanol fuel cells (μDMFCs) which are operated at 100 mW cm -2 or 400 mA cm -2. Furthermore, the condensed vapors can also be collected and recirculated with the existing micro-channels which act as a passive water recycling system for μDMFCs. The durability testing shows that the fuel cells equipped with WAMD exhibit improved stability and higher current density.

  20. Therapeutic target of memory B cells depletion helps to tailor administration frequency of rituximab in myasthenia gravis.

    PubMed

    Lebrun, Christine; Bourg, Véronique; Bresch, Saskia; Cohen, Mikael; Rosenthal-Allieri, Maria Alessandra; Desnuelle, Claude; Ticchioni, Michel

    2016-09-15

    Rituximab (RTX) has demonstrated efficacy in limiting relapses in myasthenia gravis (MG). We investigated the interest of CD27+ memory B cell monitoring in patients as a biological marker of clinical relapse. Twenty-four patients have been treated with RTX (375mg/m(2)/week-month as an induction treatment). Maintenance treatment consisted with either systematic treatment every 3months or only when CD27+ memory B cells were detectable. After the induction treatment, the mean infusions were 1.3/year compared with 4/year. We suggest that RTX administration frequency can be decreased safely by monitoring the re-emerging CD27+ memory B cells. PMID:27609279

  1. Egg incubation position affects toxicity of air cell administered PCB 126 (3,3?4,4?,5- pentachlorobiphenyl) in chicken (Gallus domesticus) embryos

    USGS Publications Warehouse

    McKernan, M.A.; Rattner, B.A.; Hale, R.C.; Ottinger, M.A.

    2007-01-01

    The avian egg is used extensively for chemical screening and determining the relative sensitivity of species to environmental contaminants (e.g., metals, pesticides, polyhalogenated compounds). The effect of egg incubation position on embryonic survival, pipping, and hatching success was examined following air cell administration of polychlorinated biphenyl (PCB) congener 126 (3,3',4,4',5-pentachlorobiphenyl [PCB 126]; 500?2,000 pg/g egg) on day 4 of development in fertile chicken (Gallus gallus) eggs. Depending on dose, toxicity was found to be up to nine times greater in vertically versus horizontally incubated eggs. This may be due to enhanced embryonic exposure to the injection bolus in vertically incubated eggs compared to more gradual uptake in horizontally incubated eggs. Following air cell administration of PCB 126, horizontal incubation of eggs may more closely approximate uptake and toxicity that has been observed with naturally incorporated contaminants. These data have implications for chemical screening and use of laboratory data for ecological risk assessments.

  2. Post-Aire maturation of thymic medullary epithelial cells involves selective expression of keratinocyte-specific autoantigens.

    PubMed

    Wang, Xiaoping; Laan, Martti; Bichele, Rudolf; Kisand, Kai; Scott, Hamish S; Peterson, Pärt

    2012-03-01

    The autoimmune regulator (Aire)-directed ectopic expression of tissue-specific antigens (TSAs) by mature medullary thymic epithelial cells (mTECs) has been viewed as an essential mechanism in the induction of central tolerance. Recent data suggest that the survival of mTECs extends beyond the Aire+ cell population to form the post-Aire mTEC population and Hassall's corpuscles (HCs). The nature and function of these post-Aire epithelial cells and structures, however, have remained unidentified. In this study, we characterized in detail the end-stage development of mTECs and HCs in both Aire-sufficient and Airedeficient mice. In addition, using a transgenic mouse model in which the LacZ reporter gene is under the control of the endogenous Aire promoter, we purified and analyzed the post-Aire mTECs to characterize their function. We showed that the end-stage maturation of mTECs closely resembles that of keratinocytes and that the lack of Aire results in a marked block of mTEC differentiation, which is partially overcome by ligands for RANK and CD40. We also provide evidence that, during mTEC development, Aire is expressed only once and during a limited 1-2 day period. The following loss of Aire expression is accompanied by a quick downregulation of MHC class II and CD80, and of most of the Aire-dependent and Aire-independent TSAs, with the exception of keratinocyte-specific genes. In the final stage of maturation, the mTECs lose their nuclei to become HCs and specifically express desmogleins (DGs) 1 and 3, which, via cross-presentation by APCs, may contribute to tolerance against these pemphigus vulgaris-related TSAs.

  3. Fuel Cell Propulsion Systems for an All-electric Personal Air Vehicle

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa L.; Schmitz, Paul C.

    2003-01-01

    There is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane and solid oxide fuel cells, alternative fuels and fuel processing, and fuel storage. This paper summarizes the results of a first-order feasibility study for an all-electric personal air vehicle utilizing a fuel cell-powered propulsion system. A representative aircraft with an internal combustion engine was chosen as a baseline to provide key parameters to the study, including engine power and subsystem mass, fuel storage volume and mass, and aircraft range. The engine, fuel tank, and associated ancillaries were then replaced with a fuel cell subsystem. Various configurations were considered including: a proton exchange membrane (PEM) fuel cell with liquid hydrogen storage; a direct methanol PEM fuel cell; and a direct internal reforming solid oxide fuel cell (SOFC)/turbine hybrid system using liquid methane fuel. Each configuration was compared to the baseline case on a mass and range basis.

  4. Fuel Cell Propulsion Systems for an All-Electric Personal Air Vehicle

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa L.

    2003-01-01

    There is a growing interest in the use of fuel cells as a power source for all-electric aircraft propulsion as a means to substantially reduce or eliminate environmentally harmful emissions. Among the technologies under consideration for these concepts are advanced proton exchange membrane and solid oxide fuel cells, alternative fuels and fuel processing, and fuel storage. This paper summarizes the results of a first-order feasibility study for an all-electric personal air vehicle utilizing a fuel cell-powered propulsion system. A representative aircraft with an internal combustion engine was chosen as a baseline to provide key parameters to the study, including engine power and subsystem mass, fuel storage volume and mass, and aircraft range. The engine, fuel tank, and associated ancillaries were then replaced with a fuel cell subsystem. Various configurations were considered including: a proton exchange membrane (PEM) fuel cell with liquid hydrogen storage; a direct methanol PEM fuel cell; and a direct internal reforming solid oxide fuel cell (SOFC)/turbine hybrid system using liquid methane fuel. Each configuration was compared to the baseline case on a mass and range basis.

  5. Temperature dependence of an abiotic glucose/air alkaline fuel cell

    NASA Astrophysics Data System (ADS)

    Orton, Dane; Scott, Daniel

    2015-11-01

    The temperature dependence of a previously developed glucose fuel cell is explored. This cell uses a small molecule dye mediator to transport oxidizable electrons from glucose to a carbon felt anode. This reaction is driven by an air breathing MnO2 cathode. This research investigates how the temperature of the system affects the power production of the fuel cell. Cell performance is observed using either methyl viologen, indigo carmine, trypan blue, or hydroquinone as a mediator at temperatures of 15, 19, 27, 32, 37, 42, and 49 °C. Cyclic voltammetry of the cell anode at the given temperatures with the individual dyes is also presented. The highest power production amongst all of the cells occurs at 32 °C. This occurs with the mediator indigo carmine or with the mediator methyl viologen. These sustained powers are 2.31 mW cm-2 and 2.39 mW cm-2, respectively. This is approximately a 350% increase for these cells compared to their power produced at room temperature. This dramatic increase is likely due to increased solubility of the mediator dye at higher temperatures.

  6. 2-Amp TPV cogenerator using forced-air cooled gallium antimonide cells

    SciTech Connect

    Fraas, L.; Avery, J.; Ballantyne, R.; Custard, P.; Ferguson, L.; Xiang, H.H.; Keyes, J.; Mulligan, B.; Samaras, J.; Williams, D.

    1997-03-01

    We will describe a wall mounted TPV cogenerator for use as a battery trickle charger and 5,000 BTU/hr room heater on boats, in remote cabins, and in recreational vehicles. Propane is used to heat a proprietary matched emitter, and the emitter is surrounded by a photovoltaic conversion array consisting of 48 GaSb cells connected in series. Warm air generated by forced-air cooling of the array cooling fins is used for room heating, while combustion exhaust gases are vented to the outside. The generator will be demonstrated at the conference. Beta site test units are presently being assembled, and production units are expected to be available this fall. {copyright} {ital 1997 American Institute of Physics.}

  7. Concise Review: Review and Perspective of Cell Dosage and Routes of Administration From Preclinical and Clinical Studies of Stem Cell Therapy for Heart Disease

    PubMed Central

    Golpanian, Samuel; Schulman, Ivonne H.; Ebert, Ray F.; Heldman, Alan W.; DiFede, Darcy L.; Yang, Phillip C.; Wu, Joseph C.; Bolli, Roberto; Perin, Emerson C.; Simari, Robert D.; Wolf, Ariel; Hare, Joshua M.

    2016-01-01

    An important stage in the development of any new therapeutic agent is establishment of the optimal dosage and route of administration. This can be particularly challenging when the treatment is a biologic agent that might exert its therapeutic effects via complex or poorly understood mechanisms. Multiple preclinical and clinical studies have shown paradoxical results, with inconsistent findings regarding the relationship between the cell dose and clinical benefit. Such phenomena can, at least in part, be attributed to variations in cell dosing or concentration and the route of administration (ROA). Although clinical trials of cell-based therapy for cardiovascular disease began more than a decade ago, specification of the optimal dosage and ROA has not been established. The present review summarizes what has been learned regarding the optimal cell dosage and ROA from preclinical and clinical studies of stem cell therapy for heart disease and offers a perspective on future directions. Significance Preclinical and clinical studies on cell-based therapy for cardiovascular disease have shown inconsistent results, in part because of variations in study-specific dosages and/or routes of administration (ROA). Future preclinical studies and smaller clinical trials implementing cell-dose and ROA comparisons are warranted before proceeding to pivotal trials. PMID:26683870

  8. Determining air quality and greenhouse gas impacts of hydrogen infrastructure and fuel cell vehicles.

    PubMed

    Stephens-Romero, Shane; Carreras-Sospedra, Marc; Brouwer, Jacob; Dabdub, Donald; Samuelsen, Scott

    2009-12-01

    Adoption of hydrogen infrastructure and hydrogen fuel cell vehicles (HFCVs) to replace gasoline internal combustion engine (ICE) vehicles has been proposed as a strategy to reduce criteria pollutant and greenhouse gas (GHG) emissions from the transportation sector and transition to fuel independence. However, it is uncertain (1) to what degree the reduction in criteria pollutants will impact urban air quality, and (2) how the reductions in pollutant emissions and concomitant urban air quality impacts compare to ultralow emission gasoline-powered vehicles projected for a future year (e.g., 2060). To address these questions, the present study introduces a "spatially and temporally resolved energy and environment tool" (STREET) to characterize the pollutant and GHG emissions associated with a comprehensive hydrogen supply infrastructure and HFCVs at a high level of geographic and temporal resolution. To demonstrate the utility of STREET, two spatially and temporally resolved scenarios for hydrogen infrastructure are evaluated in a prototypical urban airshed (the South Coast Air Basin of California) using geographic information systems (GIS) data. The well-to-wheels (WTW) GHG emissions are quantified and the air quality is established using a detailed atmospheric chemistry and transport model followed by a comparison to a future gasoline scenario comprised of advanced ICE vehicles. One hydrogen scenario includes more renewable primary energy sources for hydrogen generation and the other includes more fossil fuel sources. The two scenarios encompass a variety of hydrogen generation, distribution, and fueling strategies. GHG emissions reductions range from 61 to 68% for both hydrogen scenarios in parallel with substantial improvements in urban air quality (e.g., reductions of 10 ppb in peak 8-h-averaged ozone and 6 mug/m(3) in 24-h-averaged particulate matter concentrations, particularly in regions of the airshed where concentrations are highest for the gasoline scenario

  9. Determining air quality and greenhouse gas impacts of hydrogen infrastructure and fuel cell vehicles.

    PubMed

    Stephens-Romero, Shane; Carreras-Sospedra, Marc; Brouwer, Jacob; Dabdub, Donald; Samuelsen, Scott

    2009-12-01

    Adoption of hydrogen infrastructure and hydrogen fuel cell vehicles (HFCVs) to replace gasoline internal combustion engine (ICE) vehicles has been proposed as a strategy to reduce criteria pollutant and greenhouse gas (GHG) emissions from the transportation sector and transition to fuel independence. However, it is uncertain (1) to what degree the reduction in criteria pollutants will impact urban air quality, and (2) how the reductions in pollutant emissions and concomitant urban air quality impacts compare to ultralow emission gasoline-powered vehicles projected for a future year (e.g., 2060). To address these questions, the present study introduces a "spatially and temporally resolved energy and environment tool" (STREET) to characterize the pollutant and GHG emissions associated with a comprehensive hydrogen supply infrastructure and HFCVs at a high level of geographic and temporal resolution. To demonstrate the utility of STREET, two spatially and temporally resolved scenarios for hydrogen infrastructure are evaluated in a prototypical urban airshed (the South Coast Air Basin of California) using geographic information systems (GIS) data. The well-to-wheels (WTW) GHG emissions are quantified and the air quality is established using a detailed atmospheric chemistry and transport model followed by a comparison to a future gasoline scenario comprised of advanced ICE vehicles. One hydrogen scenario includes more renewable primary energy sources for hydrogen generation and the other includes more fossil fuel sources. The two scenarios encompass a variety of hydrogen generation, distribution, and fueling strategies. GHG emissions reductions range from 61 to 68% for both hydrogen scenarios in parallel with substantial improvements in urban air quality (e.g., reductions of 10 ppb in peak 8-h-averaged ozone and 6 mug/m(3) in 24-h-averaged particulate matter concentrations, particularly in regions of the airshed where concentrations are highest for the gasoline scenario).

  10. Influence of schedule of interleukin 2 administration on therapy with interleukin 2 and lymphokine activated killer cells.

    PubMed

    Thompson, J A; Lee, D J; Lindgren, C G; Benz, L A; Collins, C; Shuman, W P; Levitt, D; Fefer, A

    1989-01-01

    The purpose of this study was to compare the toxicity, immunomodulatory changes, and antitumor efficacy of interleukin 2 (IL-2) and lymphokine activated killer (LAK) cell therapy with two durations of IL-2 infusion. Patients with progressive melanoma, non-Hodgkin's lymphoma, renal carcinoma, or colon carcinoma received IL-2 at 3 X 10(6) units/m2/day on days 1-5 and 13-17, either by bolus injection every 8 h (q8h) or by continuous i.v. (CIV) administration. Peripheral blood mononuclear cells were harvested by leukapheresis on days 8, 9, and 10, were incubated in vitro for 5 days for generation of LAK cells, and were infused on days 13, 14, and 15. The first 11 patients were treated with IL-2 q8h, and the subsequent 13 patients were treated by CIV infusion. Toxicity consisted primarily of fever, chills, emesis, diarrhea, weight gain, and edema but did not require intensive care unit support and did not differ significantly between treatment groups. IL-2-induced lymphocytosis on day 8 was higher with CIV than with q8h administration with a mean lymphocyte count/microliter of 5610 +/- 700 (SE) versus 3300 +/- 500. Immunomodulatory changes observed on days 8 and 20 were also greater with CIV IL-2 and included an increase in peripheral blood mononuclear cell IL-2 receptor expression as well as a marked rise in the number of Leu-11+ and Leu-19+ peripheral blood mononuclear cells. The total leukapheresis yield per patient and total number of LAK cells infused per patient were higher with CIV than q8h administration, with 49.8 +/- 4.9 X 10(9) versus 39.4 +/- 5.4 X 10(9) and 42.6 +/- 5.0 X 10(9) versus 34.0 +/- 5.4 X 10(9), respectively. The cells infused displayed phenotypic evidence of activation and exhibited marked lytic reactivity to Daudi, Raji, and HT-144 targets. One complete and one minimal response were observed in 2 of 8 patients with metastatic renal cell carcinoma who received CIV IL-2 and LAK cells. The results show that IL-2 is more biologically active by CIV

  11. Aire regulates the expression of differentiation-associated genes and self-renewal of embryonic stem cells.

    PubMed

    Gu, Bin; Zhang, Jiarong; Chen, Qi; Tao, Bo; Wang, Wei; Zhou, Yang; Chen, Liangbiao; Liu, Yusen; Zhang, Ming

    2010-04-01

    Embryonic stem cells (ESCs) are pluripotent stem cells from early embryos. It has been well recognized that ESC genomes are maintained in a globally transcriptional hyperactive state, which genetically poised ESCs to the high differentiation potential. However, the transcription factors regulating the global transcription activities in ESCs are not well defined. We show here that mouse and human ESCs express two transcription factors, Aire and Deaf1. Previously known to function in the thymus stromal cells and peripheral lymphoid organs respectively, Aire and Deaf1 help regulate the ectopic expression of diverse tissue-specific antigens to establish self-immune tolerance. Differentiation of ESCs greatly reduced Aire and Deaf1 expression, in a pattern similar to the pluripotent factors, Oct4 and Nanog. Knockdown of Aire in mouse ESCs resulted in significantly decreased clone-forming efficiency as well as attenuated cell cycle, suggesting Aire plays a role in ESC self-renewal. In addition, some differentiation-associated genes that are sporadically expressed in ESCs were reduced in expression upon Aire knockdown. These results suggest that transcription factors such as Aire and Deaf1, which exert global transcriptional regulatory functions, may play important roles in self-renewal of ESCs and maintaining ESC in a transcriptionally hyperactive state.

  12. Mouse thymic epithelial cell lines expressing "Aire" and peripheral tissue-specific antigens reproduce in vitro negative selection of T cells.

    PubMed

    Yamaguchi, Yoshitaka; Takayanagi, Atsushi; Chen, Jiabing; Sakai, Kosuke; Kudoh, Jun; Shimizu, Nobuyoshi

    2011-08-15

    In the human thymus, AIRE (autoimmune regulator) gene is expressed in a very limited type of medullary thymic epithelial cells (mTECs) and no cognate cell lines are available, hence the molecular analysis of AIRE gene function has been difficult. To improve this situation, we attempted to isolate Aire-expressing cells and established three cell lines (Aire⁺TEC1, Aire⁺TEC2, Aire⁺DC) from the abnormally enlarged thymus, which was developed in the transgenic mice expressing SV40 T-antigen driven by the mouse Aire gene promoter. When these Aire⁺ cell lines were co-cultured with fresh thymocytes, they adhered to the majority of thymocytes and induced apoptosis as if negative selection of T-cells in the thymus is occurring in vitro. Further analysis revealed that these Aire⁺ cell lines are derived from mTECs and exhibit characteristic natures of "antigen presenting cells" including several distinct abilities: to express a variety of peripheral tissue-specific antigens, to produce immunoproteasome and immunological synapse, and to express some of TNFSFs (tumor necrosis factor super families). Thus, the newly established Aire⁺ cell lines will be invaluable for the further detailed analysis of AIRE gene function in the central tolerance of immunity and autoimmune disease.

  13. Solid oxide fuel cells, and air electrode and electrical interconnection materials therefor

    DOEpatents

    Bates, J.L.

    1992-09-01

    In one aspect of the invention, an air electrode material for a solid oxide fuel cell comprises Y[sub 1[minus]a]Q[sub a]MnO[sub 3], where Q is selected from the group consisting of Ca and Sr or mixtures thereof and a' is from 0.1 to 0.8. Preferably, a' is from 0.4 to 0.7. In another aspect of the invention, an electrical interconnection material for a solid oxide fuel cell comprises Y[sub 1[minus]b]Ca[sub b]Cr[sub 1[minus]c]Al[sub c]O[sub 3], where b' is from 0.1 to 0.6 and c' is from 0 to 9.3. Preferably, b' is from 0.3 to 0.5 and c' is from 0.05 to 0.1. A composite solid oxide electrochemical fuel cell incorporating these materials comprises: a solid oxide air electrode and an adjacent solid oxide electrical interconnection which commonly include the cation Y, the air electrode comprising Y[sub 1[minus]a]Q[sub a]MnO[sub 3], where Q is selected from the group consisting of Ca and Sr or mixtures thereof and a' is from 0.1 to 0.8, the electrical interconnection comprising Y[sub 1[minus]b]Ca[sub b]Cr[sub 1[minus]c]Al[sub c]O[sub 3], where b' is from 0.1 to 0.6 and c' is from 0.0 to 0.3; a yttrium stabilized solid electrolyte comprising (1[minus]d)ZrO[sub 2]-(d)Y[sub 2]O[sub 3] where d' is from 0.06 to 0.5; and a solid fuel electrode comprising X-ZrO[sub 2], where X' is an elemental metal. 5 figs.

  14. Solid oxide fuel cells, and air electrode and electrical interconnection materials therefor

    DOEpatents

    Bates, J. Lambert

    1992-01-01

    In one aspect of the invention, an air electrode material for a solid oxide fuel cell comprises Y.sub.1-a Q.sub.a MnO.sub.3, where "Q" is selected from the group consisting of Ca and Sr or mixtures thereof and "a" is from 0.1 to 0.8. Preferably, "a" is from 0.4 to 0.7. In another aspect of the invention, an electrical interconnection material for a solid oxide fuel cell comprises Y.sub.1-b Ca.sub.b Cr.sub.1-c Al.sub.c O.sub.3, where "b" is from 0.1 to 0.6 and "c" is from 0 to 9.3. Preferably, "b" is from 0.3 to 0.5 and "c" is from 0.05 to 0.1. A composite solid oxide electrochemical fuel cell incorporating these materials comprises: a solid oxide air electrode and an adjacent solid oxide electrical interconnection which commonly include the cation Y, the air electrode comprising Y.sub.1-a Q.sub.a MnO.sub.3, where "Q" is selected from the group consisting of Ca and Sr or mixtures thereof and "a" is from 0.1 to 0.8, the electrical interconnection comprising Y.sub.1-b Ca.sub.b Cr.sub.1-c Al.sub.c O.sub.3, where "b" is from 0.1 to 0.6 and "c" is from 0.0 to 0.3; a yttrium stabilized solid electrolyte comprising (1-d)ZrO.sub.2 -(d)Y.sub.2 O.sub.3 where "d" is from 0.06 to 0.5; and a solid fuel electrode comprising X-ZrO.sub.2, where "X" is an elemental metal.

  15. Emerging Fuel Cell Technology Being Developed: Offers Many Benefits to Air Vehicles

    NASA Technical Reports Server (NTRS)

    Walker, James F.; Civinskas, Kestutis C.

    2004-01-01

    Fuel cells, which have recently received considerable attention for terrestrial applications ranging from automobiles to stationary power generation, may enable new aerospace missions as well as offer fuel savings, quiet operations, and reduced emissions for current and future aircraft. NASA has extensive experience with fuel cells, having used them on manned space flight systems over four decades. Consequently, the NASA Glenn Research Center has initiated an effort to investigate and develop fuel cell technologies for multiple aerospace applications. Two promising fuel cell types are the proton exchange membrane (PEM) and solid oxide fuel cell (SOFC). PEM technology, first used on the Gemini spacecraft in the sixties, remained unutilized thereafter until the automotive industry recently recognized the potential. PEM fuel cells are low-temperature devices offering quick startup time but requiring relatively pure hydrogen fuel. In contrast, SOFCs operate at high temperatures and tolerate higher levels of impurities. This flexibility allows SOFCs to use hydrocarbon fuels, which is an important factor considering our current liquid petroleum infrastructure. However, depending on the specific application, either PEM or SOFC can be attractive. As only NASA can, the Agency is pursuing fuel cell technology for civil uninhabited aerial vehicles (UAVs) because it offers enhanced scientific capabilities, including enabling highaltitude, long-endurance missions. The NASA Helios aircraft demonstrated altitudes approaching 100,000 ft using solar power in 2001, and future plans include the development of a regenerative PEM fuel cell to provide nighttime power. Unique to NASA's mission, the high-altitude aircraft application requires the PEM fuel cell to operate on pure oxygen, instead of the air typical of terrestrial applications.

  16. Effect of mode of administration of methyl methanesulfonate and triethylenemelamine on induction of unscheduled DNA synthesis in mouse germ cells

    SciTech Connect

    Sheu, C.W.; Sega, G.A.; Owens, J.G.

    1987-01-01

    The effect of route of administration on induction of unscheduled DNA synthesis (UDS) in mouse germ cells in vivo was studied using two germ cell mutagens, methyl methanesulfonate (MMS) and triethylenemelamine (TEM). The chemicals were administered to male mice (C3Hf x 101)F/sub 1/ by IP injection or gavage using acute or 5-day subacute regimens. After completion of dosing, methyl-(/sup 3/H)thymidine ((/sup 3/H)TdR) was injected into the testes, and spermatozoa were collected 16 days later. The sperm heads were isolated, and UDS was determined by the amount of (/sup 3/H)TdR incorporated. Acute administration of MMS (2-100 mg/kg) induced a strong, dose-related UDS response. The response was slightly higher with IP injection than with gavage. Acute administration of TEM (0.05-4.0 mg/kg) by IP injection or gavage induced weak and variable responses. The study showed that gavage, as well as IP injection, can be used for the administration of test chemicals and that the subacute 5-day regimen induced a higher UDS response than the acute regimen. Furthermore, the testicular route may enhance the detection of weak UDS inducers.

  17. Administration of a polyvalent mechanical bacterial lysate to elderly patients with COPD: Effects on circulating T, B and NK cells.

    PubMed

    Lanzilli, Giulia; Traggiai, Elisabetta; Braido, Fulvio; Garelli, Valentina; Folli, Chiara; Chiappori, Alessandra; Riccio, Anna Maria; Bazurro, Gyada; Agazzi, Alessia; Magnani, Alessandra; Canonica, Giorgio Walter; Melioli, Giovanni

    2013-01-01

    The modifications of the subsets of circulating lymphocytes were evaluated in a group of patients with COPD undergoing treatment with a polyvalent mechanical bacterial lysate (PMBL), a drug that is able to significantly modify the natural history of these patients. Using multicolor immune-florescence and flow cytometry, T, B subsets and NK cells were extensively studied both in the group of treated patients and in a disease and age matched controls. Despite the age, in treated patients, T and NK cells were significantly increased in numbers of circulating cells, but not in percentages, while B cells remained unmodified. CD3+4+T cells were increased in treated patients, while CD3+CD8T cells were unmodified by the treatment. Activated T cells were increased but Treg, resulted reduced both in percentage than in absolute numbers. Transitional B cells resulted increased (in percentage and in absolute numbers) in their late maturation step (T3), while only early Naïve B cells were increased by the treatment, while other naïve subpopulations were unmodified. Memory B cells were reduced in percentage (but remained unmodified as absolute numbers), while the most immature form of memory B cells was significantly increased. Finally, both switch memory B cells and plasma cells resulted unmodified by the PMBL treatment. These results clearly indicated that the administration of the PMBL, even in elderly patients with COPD, was able to induce a significant immune-stimulation and these results, at cellular level, clearly support the evidence that the mechanism of action of PMBL is strictly related to a direct effect on immune-competent cells. PMID:23206888

  18. Autoimmune Regulator (AIRE) Is Expressed in Spermatogenic Cells, and It Altered the Expression of Several Nucleic-Acid-Binding and Cytoskeletal Proteins in Germ Cell 1 Spermatogonial (GC1-spg) Cells.

    PubMed

    Radhakrishnan, Karthika; Bhagya, Kongattu P; Kumar, Anil Tr; Devi, Anandavalli N; Sengottaiyan, Jeeva; Kumar, Pradeep G

    2016-08-01

    Autoimmune regulator (AIRE) is a gene associated with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED). AIRE is expressed heavily in the thymic epithelial cells and is involved in maintaining self-tolerance through regulating the expression of tissue-specific antigens. The testes are the most predominant extrathymic location where a heavy expression of AIRE is reported. Homozygous Aire-deficient male mice were infertile, possibly due to impaired spermatogenesis, deregulated germ cell apoptosis, or autoimmunity. We report that AIRE is expressed in the testes of neonatal, adolescent, and adult mice. AIRE expression was detected in glial cell derived neurotrophic factor receptor alpha (GFRα)(+) (spermatogonia), GFRα(-)/synaptonemal complex protein (SCP3)(+) (meiotic), and GFRα(-)/Phosphoglycerate kinase 2 (PGK2)(+) (postmeiotic) germ cells in mouse testes. GC1-spg, a germ-cell-derived cell line, did not express AIRE. Retinoic acid induced AIRE expression in GC1-spg cells. Ectopic expression of AIRE in GC1-spg cells using label-free LC-MS/MS identified a total of 371 proteins that were differentially expressed. 100 proteins were up-regulated, and 271 proteins were down-regulated. Data are available via ProteomeXchange with identifier PXD002511. Functional analysis of the differentially expressed proteins showed increased levels of various nucleic-acid-binding proteins and transcription factors and a decreased level of various cytoskeletal and structural proteins in the AIRE overexpressing cells as compared with the empty vector-transfected controls. The transcripts of a select set of the up-regulated proteins were also elevated. However, there was no corresponding decrease in the mRNA levels of the down-regulated set of proteins. Molecular function network analysis indicated that AIRE influenced gene expression in GC1-spg cells by acting at multiple levels, including transcription, translation, RNA processing, protein transport, protein

  19. Timed, sequential administration of paclitaxel improves its cytotoxic effectiveness in a cell culture model

    PubMed Central

    Fisi, Viktória; Kátai, Emese; Bogner, Péter; Miseta, Attila; Nagy, Tamás

    2016-01-01

    ABSTRACT Paclitaxel (taxol) is a chemotherapeutic agent frequently used in combination with other anti-neoplastic drugs. It is most effective during the M phase of the cell-cycle and tends to cause synchronization in malignant cells lines. In this study, we investigated whether timed, sequential treatment based on the cell-cycle characteristics could be exploited to enhance the cytotoxic effect of paclitaxel. We characterized the cell-cycle properties of a rapidly multiplying cell line (Sp2, mouse myeloma cells) by propidium-iodide DNA staining such as the lengths of various cell cycle phases and population duplication time. Based on this we designed a paclitaxel treatment protocol that comprised a primary and a secondary, timed treatment. We found that the first paclitaxel treatment synchronized the cells at the G2/M phase but releasing the block by stopping the treatment allowed a large number of cells to enter the next cell-cycle by a synchronized manner. The second treatment was most effective during the time when these cells approached the next G2/M phase and was least effective when it occurred after the peak time of this next G2/M phase. Moreover, we found that after mixing Sp2 cells with another, significantly slower multiplying cell type (Jurkat human T-cell leukemia) at an initial ratio of 1:1, the ratio of the two different cell types could be influenced by timed sequential paclitaxel treatment at will. Our results demonstrate that knowledge of the cell-cycle parameters of a specific malignant cell type could improve the effectivity of the chemotherapy. Implementing timed chemotherapeutic treatments could increase the cytotoxicity on the malignant cells but also decrease the side-effects since other, non-malignant cell types will have different cell-cycle characteristic and be out of synch during the treatment. PMID:27104236

  20. Timed, sequential administration of paclitaxel improves its cytotoxic effectiveness in a cell culture model.

    PubMed

    Fisi, Viktória; Kátai, Emese; Bogner, Péter; Miseta, Attila; Nagy, Tamás

    2016-05-01

    Paclitaxel (taxol) is a chemotherapeutic agent frequently used in combination with other anti-neoplastic drugs. It is most effective during the M phase of the cell-cycle and tends to cause synchronization in malignant cells lines. In this study, we investigated whether timed, sequential treatment based on the cell-cycle characteristics could be exploited to enhance the cytotoxic effect of paclitaxel. We characterized the cell-cycle properties of a rapidly multiplying cell line (Sp2, mouse myeloma cells) by propidium-iodide DNA staining such as the lengths of various cell cycle phases and population duplication time. Based on this we designed a paclitaxel treatment protocol that comprised a primary and a secondary, timed treatment. We found that the first paclitaxel treatment synchronized the cells at the G2/M phase but releasing the block by stopping the treatment allowed a large number of cells to enter the next cell-cycle by a synchronized manner. The second treatment was most effective during the time when these cells approached the next G2/M phase and was least effective when it occurred after the peak time of this next G2/M phase. Moreover, we found that after mixing Sp2 cells with another, significantly slower multiplying cell type (Jurkat human T-cell leukemia) at an initial ratio of 1:1, the ratio of the two different cell types could be influenced by timed sequential paclitaxel treatment at will. Our results demonstrate that knowledge of the cell-cycle parameters of a specific malignant cell type could improve the effectivity of the chemotherapy. Implementing timed chemotherapeutic treatments could increase the cytotoxicity on the malignant cells but also decrease the side-effects since other, non-malignant cell types will have different cell-cycle characteristic and be out of synch during the treatment. PMID:27104236

  1. CuInS(2) solar cells by air-stable ink rolling.

    PubMed

    Weil, Benjamin D; Connor, Stephen T; Cui, Yi

    2010-05-19

    Solution-based deposition techniques are widely considered to be a route to low-cost, high-throughput photovoltaic device fabrication. In this report, we establish a methodology for a highly scalable deposition process and report the synthesis of an air-stable, vulcanized ink from commercially available precursors. Using our air-stable ink rolling (AIR) process, we can make solar cells with an absorber layer that is flat, contaminant-free, and composed of large-grained CuInS(2). The current-voltage characteristics of the devices were measured in the dark and under 100 mW/cm(2) illumination intensity, and the devices were found to have J(sc) = 18.49 mA/cm(2), V(oc) = 320 mV, FF = 0.37, and eta = 2.15%. This process has the ability to produce flat, contaminant-free, large-grained films similar to those produced by vacuum deposition, and its versatility should make it capable of producing a variety of materials for electronic, optoelectronic, and memory devices.

  2. Continuous flow membrane-less air cathode microbial fuel cell with spunbonded olefin diffusion layer.

    PubMed

    Tugtas, Adile Evren; Cavdar, Pelin; Calli, Baris

    2011-11-01

    The power production performance of a membrane-less air-cathode microbial fuel cell was evaluated for 53 days. Anode and cathode electrodes and the micro-fiber cloth separator were configured by sandwiching the separator between two electrodes. In addition, the air-facing side of the cathode was covered with a spunbonded olefin sheet instead of polytetrafluoroethylene (PTFE) coating to control oxygen diffusion and water loss. The configuration resulted in a low resistance of about 4Ω and a maximum power density of 750 mW/m2. However, as a result of a gradual decrease in the cathode potential, maximum power density decreased to 280 mW/m2. The declining power output was attributed to loss of platinum catalyst (8.26%) and biomass growth (38.44%) on the cathode. Coulombic efficiencies over 55% and no water leakage showed that the spunbonded olefin sheet covering the air-facing side of the cathode can be a cost-effective alternative to PTFE coating.

  3. Hydrogen-air detonation cells computed using skeletal and reduced reaction mechanisms

    NASA Astrophysics Data System (ADS)

    Kessler, David; Taylor, Brian; Gamezo, Vadim; Oran, Elaine

    2011-11-01

    The multidimensional instability of gas-phase detonations results in a complex dynamic structure at the detonation front that leaves behind characteristic cellular patterns as it propagates. In fuel-air mixtures with high effective activation energies, such as hydrogen and air, these detonation cells can become irregular and modelling this behavior using reduced chemical reaction mechanisms can be challenging. Using complex reaction mechanisms, however, can be computationally overwhelming for problems of practical interest. We compare the reaction front structures and dynamic behavior of two-dimensional detonations in a stoichiometric hydrogen-air mixture computed using a 12-step skeletal mechanism and several reduced mechanisms, including a calibrated one-step model. We pay particular attention to how transverse instabilities that form in this high-activation-energy mixture are affected by the details of the chemistry model. We then discuss how to adjust the parameters in reduced reaction models to better describe irregular triple point behavior. NAS/NRC Postdoctoral Research Associate.

  4. Power generation by packed-bed air-cathode microbial fuel cells.

    PubMed

    Zhang, Xiaoyuan; Shi, Juan; Liang, Peng; Wei, Jincheng; Huang, Xia; Zhang, Chuanyi; Logan, Bruce E

    2013-08-01

    Catalysts and catalyst binders are significant portions of the cost of microbial fuel cell (MFC) cathodes. Many materials have been tested as aqueous cathodes, but air-cathodes are needed to avoid energy demands for water aeration. Packed-bed air-cathodes were constructed without expensive binders or diffusion layers using four inexpensive carbon-based materials. Cathodes made from activated carbon produced the largest maximum power density of 676 ± 93 mW/m(2), followed by semi-coke (376 ± 47 mW/m(2)), graphite (122 ± 14 mW/m(2)) and carbon felt (60 ± 43 mW/m(2)). Increasing the mass of activated carbon and semi-coke from 5 to ≥ 15 g significantly reduced power generation because of a reduction in oxygen transfer due to a thicker water layer in the cathode (∼3 or ∼6 cm). These results indicate that a thin packed layer of activated carbon or semi-coke can be used to make inexpensive air-cathodes for MFCs. PMID:23732924

  5. Roll and Cell Convection in Wintertime Arctic Cold-Air Outbreaks.

    NASA Astrophysics Data System (ADS)

    Brümmer, Burghard

    1999-08-01

    Cold-air outbreaks from the polar ice caps or winterly continents over the open ocean lead to organized convection that typically starts as longitudinal roll patterns and changes to cellular patterns in downstream direction. During the field experiments ARKTIS 1991 and ARKTIS 1993, aircraft missions were conducted in 13 cold-air outbreak events over the Greenland and Barents Seas to determine the characteristic parameters of both the mean (primary) flow and the superimposed organized convection (secondary flow). The measurements are classified into four categories with respect to the convective pattern form: longitudinal rolls with small and wider horizontal wavelengths, transitional forms between rolls and cells, and cells.Rolls were observed for boundary layer depths h < 1 km with horizontal wavelengths < 5 km and aspect ratios /h between 2.6 and 6.5. Distinct cellular structures occurred for h > 1.4 km with > 8 km and /h between 4 and 12. The amplitudes of the secondary flow-scale variations of the temperature R, moisture mR, and the longitudinal, uR; transversal, R; and vertical, wR, wind components were on the order of 0.1-0.4 K, 0.03-0.30 g kg1, 0.6-2.5 m s1, 0.8-2.5 m s1, and 0.4-1.8 m s1, respectively, generally increasing from the roll to the cell region. The same is true for the ratio uR/R (from about 0.6 to nearly 1) and for the ratio LmR/cpR (from 0.7 to more than 2), hinting at increasing importance of moisture processes in the cell compared to the roll region.The importance of the secondary-flow transports of heat and momentum in relation to the total vertical transports increases with height and from rolls to cells. Particularly clear is the vertical profile of the vertical moisture transport mRwR, which exhibits a maximum around cloud base and is on the average related to the surface moisture flux as (mRwR)max = 0.35(mw)o.The thermodynamic conditions of the basic flow are characterized by the Rayleigh number Ra, the stability of the capping

  6. Antiproliferative effects on colon adenocarcinoma cells induced by co-administration of vitamin K1 and Lactobacillus rhamnosus GG.

    PubMed

    Orlando, Antonella; Linsalata, Michele; Russo, Francesco

    2016-06-01

    Vitamin K (VK), an essential nutrient associated with the clotting cascade, has also been demonstrated to have anticancer properties in various cancer cells including colon cancer cells. Also probiotics have gained interest as potential anticancer agents. Among them, Lactobacillus rhamnosus GG (L.GG) has been shown to inhibit cell proliferation and polyamine biosynthesis as well as to induce apoptosis in different human gastrointestinal cancer cells. Nevertheless, the exact mechanisms involved in these actions are not completely elucidated. Therefore, the aims of the present study were to evaluate in three differently graded human colon cancer cells (namely Caco-2, HT-29 and SW480) the effects of increasing VK1 concentrations, administered alone or in combination with viable L.GG, on the cell proliferation evaluated by MTT test, apoptosis investigated by Bax/Bcl-2 ratio and the percentage of the apoptotic cells, and the cell cycle evaluated by MUSE cell analyzer. Both VK1 and L.GG administered alone up to 72 h, caused inhibition of proliferation, induction of apoptosis and the cell cycle arrest in all the tested colon cancer cells. When VK1 and L.GG were co-administered, the addition of increasing VK1 concentrations potentiated the probiotic antiproliferative effect in a dose-dependent manner, being also related to the individual features of each cell line. The effect was more evident in Caco-2 and HT-29 cells compared to the less differentiated SW480. The enhanced antiproliferative efficacy due to co-administration of L.GG and VK1 could represent a suitable option in a functional food strategy for cancer growth inhibition and chemoprevention.

  7. Antiproliferative effects on colon adenocarcinoma cells induced by co-administration of vitamin K1 and Lactobacillus rhamnosus GG.

    PubMed

    Orlando, Antonella; Linsalata, Michele; Russo, Francesco

    2016-06-01

    Vitamin K (VK), an essential nutrient associated with the clotting cascade, has also been demonstrated to have anticancer properties in various cancer cells including colon cancer cells. Also probiotics have gained interest as potential anticancer agents. Among them, Lactobacillus rhamnosus GG (L.GG) has been shown to inhibit cell proliferation and polyamine biosynthesis as well as to induce apoptosis in different human gastrointestinal cancer cells. Nevertheless, the exact mechanisms involved in these actions are not completely elucidated. Therefore, the aims of the present study were to evaluate in three differently graded human colon cancer cells (namely Caco-2, HT-29 and SW480) the effects of increasing VK1 concentrations, administered alone or in combination with viable L.GG, on the cell proliferation evaluated by MTT test, apoptosis investigated by Bax/Bcl-2 ratio and the percentage of the apoptotic cells, and the cell cycle evaluated by MUSE cell analyzer. Both VK1 and L.GG administered alone up to 72 h, caused inhibition of proliferation, induction of apoptosis and the cell cycle arrest in all the tested colon cancer cells. When VK1 and L.GG were co-administered, the addition of increasing VK1 concentrations potentiated the probiotic antiproliferative effect in a dose-dependent manner, being also related to the individual features of each cell line. The effect was more evident in Caco-2 and HT-29 cells compared to the less differentiated SW480. The enhanced antiproliferative efficacy due to co-administration of L.GG and VK1 could represent a suitable option in a functional food strategy for cancer growth inhibition and chemoprevention. PMID:27035094

  8. Effects of intravenous administration of umbilical cord blood CD34(+) cells in a mouse model of neonatal stroke.

    PubMed

    Tsuji, M; Taguchi, A; Ohshima, M; Kasahara, Y; Sato, Y; Tsuda, H; Otani, K; Yamahara, K; Ihara, M; Harada-Shiba, M; Ikeda, T; Matsuyama, T

    2014-03-28

    Neonatal stroke occurs in approximately 1/4000 live births and results in life-long neurological impairments: e.g., cerebral palsy. Currently, there is no evidence-based specific treatment for neonates with stroke. Several studies have reported the benefits of umbilical cord blood (UCB) cell treatment in rodent models of neonatal brain injury. However, all of the studies examined the effects of administering either the UCB mononuclear cell fraction or UCB-derived mesenchymal stem cells in neonatal rat models. The objective of this study was to examine the effects of human UCB CD34(+) cells (hematopoietic stem cell/endothelial progenitor cells) in a mouse model of neonatal stroke, which we recently developed. On postnatal day 12, immunocompromized (SCID) mice underwent permanent occlusion of the left middle cerebral artery (MCAO). Forty-eight hours after MCAO, human UCB CD34(+) cells (1×10(5)cells) were injected intravenously into the mice. The area in which cerebral blood flow (CBF) was maintained was temporarily larger in the cell-treated group than in the phosphate-buffered saline (PBS)-treated group at 24h after treatment. With cell treatment, the percent loss of ipsilateral hemispheric volume was significantly ameliorated (21.5±1.9%) compared with the PBS group (25.6±5.1%) when assessed at 7weeks after MCAO. The cell-treated group did not exhibit significant differences from the PBS group in either rotarod (238±46s in the sham-surgery group, 175±49s in the PBS group, 203±54s in the cell-treated group) or open-field tests. The intravenous administration of human UCB CD34(+) cells modestly reduced histological ischemic brain damage after neonatal stroke in mice, with a transient augmentation of CBF in the peri-infarct area. PMID:24444827

  9. In vitro co-culture systems for studying molecular basis of cellular interaction between Aire-expressing medullary thymic epithelial cells and fresh thymocytes.

    PubMed

    Yamaguchi, Yoshitaka; Kudoh, Jun; Yoshida, Tetsuhiko; Shimizu, Nobuyoshi

    2014-10-17

    We previously established three mouse cell lines (Aire(+)TEC1, Aire(+)TEC2 and Aire(+)DC) from the medullary thymic epithelial cells (mTECs) and dendritic cells (mDCs). These cells constitutively expressed "autoimmune regulator (Aire) gene" and they exhibited various features of self antigen-presenting cells (self-APCs) present in the thymic medullary region. Here, we confirmed our previous observation that Aire(+) thymic epithelial cells adhere to fresh thymocytes and kill them by inducing apoptosis, thus potentially reproducing in vitro some aspects of the negative selection of T cells in vivo. In this system, a single Aire(+) cell appeared able to kill ∼30 thymocytes within 24 hrs. Moreover, we observed that ectopic expression of peripheral tissue-specific antigens (TSAs), and expression of several surface markers involved in mTEC development, increased as Aire(+) cell density increases toward confluency. Thus, these Aire(+) cells appear to behave like differentiating mTECs as if they pass through the developmental stages from intermediate state toward mature state. Surprisingly, an in vitro co-culture system consisting of Aire(+) cells and fractionated sub-populations of fresh thymocytes implied the possible existence of two distinct subtypes of thymocytes (named as CD4(+) killer and CD4(-) rescuer) that may determine the fate (dead or alive) of the differentiating Aire(+)mTECs. Thus, our in vitro co-culture system appears to mimic a part of "in vivo thymic crosstalk".

  10. A one-compartment fructose/air biological fuel cell based on direct electron transfer.

    PubMed

    Wu, Xuee; Zhao, Feng; Varcoe, John R; Thumser, Alfred E; Avignone-Rossa, Claudio; Slade, Robert C T

    2009-10-15

    The construction and characterization of a one-compartment fructose/air biological fuel cell (BFC) based on direct electron transfer is reported. The BFC employs bilirubin oxidase and d-fructose dehydrogenase adsorbed on a cellulose-multiwall carbon nanotube (MWCNT) matrix, reconstituted with an ionic liquid, as the biocathode and the bioanode for oxygen reduction and fructose oxidation reactions, respectively. The performance of the bioelectrode was investigated by chronoamperometric and cyclic voltammetric techniques in a standard three-electrode cell, and the polarization and long-term stability of the BFC was tested by potentiostatic discharge. An open circuit voltage of 663 mV and a maximum power density of 126 microWcm(-2) were obtained in buffer at pH 5.0. Using this regenerated cellulose-MWCNT matrix as the immobilization platform, this BFC has shown a relatively high performance and long-term stability compared with previous studies.

  11. Dependence on material choice of degradation of organic solar cells following exposure to humid air

    PubMed Central

    Glen, Tom S.; Scarratt, Nicholas W.; Yi, Hunan; Iraqi, Ahmed; Wang, Tao; Kingsley, James; Buckley, Alastair R.; Lidzey, David G.

    2015-01-01

    ABSTRACT Electron microscopy has been used to study the degradation of organic solar cells when exposed to humid air. Devices with various different combinations of commonly used organic solar cell hole transport layers and cathode materials have been investigated. In this way the ingress of water and the effect it has on devices could be studied. It was found that calcium and aluminum in the cathode both react with water, causing voids and delamination within the device. The use of poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) was found to increase the degradation by easing water ingress into the device. Replacing these materials removed these degradation features. © 2015 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 216–224 PMID:27594763

  12. Spectroscopic characterization of discharge products in Li-Air cells with aprotic carbonate electrolytes

    SciTech Connect

    Veith, Gabriel M; Nanda, Jagjit; Howe, Jane Y; Dudney, Nancy J

    2011-01-01

    Raman, infrared and X-ray photoelectron spectroscopies were used to characterize the thick coating of reaction products on carbon and MnO2 coated carbon cathodes produced during discharge of Li-air cells. The results show that neither Li2O2 or Li2O are major components of the insoluble discharge products; instead the products are largely composed of fluorine, lithium, and carbon, with surprisingly little oxygen. The complex reaction chemistry also appears to involve the formation of ethers or alkoxide products at the expense of the carbonate solvent molecules (ethylene carbonate and dimethylcarbonate). The irreversible discharge reaction is likely electrochemically promoted with Li-anion species and dissolved oxygen. Exactly how the molecular O2 participates in the reaction is unclear and requires further study. The addition of a conformal coating of MnO2 on the carbon lowers the cell s operating voltage, but does not alter the overall discharge chemistry.

  13. A Janus-paper PDMS platform for air-liquid interface cell culture applications

    NASA Astrophysics Data System (ADS)

    Rahimi, Rahim; Ochoa, Manuel; Donaldson, Amy; Parupudi, Tejasvi; Dokmeci, Mehmet R.; Khademhosseini, Ali; Ghaemmaghami, Amir; Ziaie, Babak

    2015-05-01

    A commercially available Janus paper with one hydrophobic (polyethylene-coated) face and a hygroscopic/hydrophilic one is irreversibly bonded to a polydimethylsiloxane (PDMS) substrate incorporating microfluidic channels via corona discharge surface treatment. The bond strength between the polymer-coated side and PDMS is characterized as a function of corona treatment time and annealing temperature/time. A maximum strength of 392 kPa is obtained with a 2 min corona treatment followed by 60 min of annealing at 120 °C. The water contact angle of the corona-treated polymer side decreases with increased discharge duration from 98° to 22°. The hygroscopic/hydrophilic side is seeded with human lung fibroblast cells encapsulated in a methacrylated gelatin (GelMA) hydrogel to show the potential of this technology for nutrient and chemical delivery in an air-liquid interface cell culture.

  14. Water management in a planar air-breathing fuel cell array using operando neutron imaging

    NASA Astrophysics Data System (ADS)

    Coz, E.; Théry, J.; Boillat, P.; Faucheux, V.; Alincant, D.; Capron, P.; Gébel, G.

    2016-11-01

    Operando Neutron imaging is used for the investigation of a planar air-breathing array comprising multiple cells in series. The fuel cell demonstrates a stable power density level of 150 mW/cm2. Water distribution and quantification is carried out at different operating points. Drying at high current density is observed and correlated to self-heating and natural convection. Working in dead-end mode, water accumulation at lower current density is largely observed on the anode side. However, flooding mechanisms are found to begin with water condensation on the cathode side, leading to back-diffusion and anodic flooding. Specific in-plane and through-plane water distribution is observed and linked to the planar array design.

  15. Dependence on material choice of degradation of organic solar cells following exposure to humid air

    PubMed Central

    Glen, Tom S.; Scarratt, Nicholas W.; Yi, Hunan; Iraqi, Ahmed; Wang, Tao; Kingsley, James; Buckley, Alastair R.; Lidzey, David G.

    2015-01-01

    ABSTRACT Electron microscopy has been used to study the degradation of organic solar cells when exposed to humid air. Devices with various different combinations of commonly used organic solar cell hole transport layers and cathode materials have been investigated. In this way the ingress of water and the effect it has on devices could be studied. It was found that calcium and aluminum in the cathode both react with water, causing voids and delamination within the device. The use of poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) was found to increase the degradation by easing water ingress into the device. Replacing these materials removed these degradation features. © 2015 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 216–224

  16. Fanca-/- hematopoietic stem cells demonstrate a mobilization defect which can be overcome by administration of the Rac inhibitor NSC23766.

    PubMed

    Milsom, Michael D; Lee, Andrew W; Zheng, Yi; Cancelas, Jose A

    2009-07-01

    Fanconi anemia is a severe bone marrow failure syndrome resulting from inactivating mutations of Fanconi anemia pathway genes. Gene and cell therapy trials using hematopoietic stem cells and progenitors have been hampered by poor mobilization of HSC to peripheral blood in response to G-CSF. Using a murine model of Fanconi anemia (Fanca(-/-) mice), we found that the Fanca deficiency was associated with a profound defect in hematopoietic stem cells and progenitors mobilization in response to G-CSF in absence of bone marrow failure, which correlates with the findings of clinical trials in Fanconi anemia patients. This mobilization defect was overcome by co-administration of the Rac inhibitor NSC23766, suggesting that Rac signaling is implicated in the retention of Fanca(-/-) hematopoietic stem cells and progenitors in the bone marrow. In view of these data, we propose that targeting Rac signaling may enhance G-CSF-induced HSC mobilization in Fanconi anemia.

  17. Influence of air contaminants on planar, self-breathing hydrogen PEM fuel cells in an outdoor environment

    NASA Astrophysics Data System (ADS)

    Biesdorf, Johannes; Zamel, Nada; Kurz, Timo

    2014-02-01

    In this study, the effects of air contaminants on the operation of air-breathing fuel cells in an outdoor environment are investigated. For this purpose, a unique testing platform, which allows continuous operation of 30 cells at different locations, was developed. Three of these testing platforms were placed at different sites in Freiburg im Breisgau, Germany, with high variances of weather and pollution patterns. These locations range from a highly polluted place next to a busy highway to a location with virtually pure air at an altitude of 1205 m. The fuel cells were tested at all sites for over 4500 h in continuous operation. The degradation of the cells due to air pollutants was measured as a voltage decrease for three different operation loads and membranes from two different manufactures. As the temperature of the fuel cells has not been regulated, the irreversible degradation of the cell voltages could not be isolated from the dominant influence of the temperature in the raw data. With the use of the measured data, the impact of real mixtures of air contaminants was observed to be mainly reversible.

  18. Scintigraphic tracking of mesenchymal stem cells after portal, systemic intravenous and splenic administration in healthy beagle dogs.

    PubMed

    Spriet, Mathieu; Hunt, Geraldine B; Walker, Naomi J; Borjesson, Dori L

    2015-01-01

    Mesenchymal stem cells have been proposed to treat liver disease in the dog. The objective of this study was to compare portal, systemic intravenous and splenic injections for administration of mesenchymal stem cells to target the liver in healthy beagle dogs. Four healthy beagle dogs were included in the study. Each dog received mesenchymal stem cells via all three delivery methods in randomized order, 1 week apart. Ten million fat-derived allogeneic mesenchymal stem cells labeled with Technetium-99m (99mTc)-hexamethyl-propylene amine oxime(HMPAO) were used for each injection. Right lateral, left lateral, ventral, and dorsal scintigraphic images were obtained with a gamma camera equipped with a low-energy all-purpose collimator immediately after injection and 1, 6, and 24 h later. Mesenchymal stem cells distribution was assessed subjectively using all four views. Pulmonary, hepatic, and splenic uptake was quantified from the right lateral view, at each time point. Portal injection resulted in diffuse homogeneous high uptake through the liver, whereas the systemic intravenous injection led to mesenchymal stem cell trapping in the lungs. After splenic injection, mild splenic retention and high homogeneous diffuse hepatic uptake were observed. Systemic injection of mesenchymal stem cells may not be a desirable technique for liver therapy due to pulmonary trapping. Splenic injection represents a good alternative to portal injection. Scintigraphic tracking with 99mTc-HMPAO is a valuable technique for assessing mesenchymal stem cells distribution and quantification shortly after administration. Data obtained at 24 h should be interpreted cautiously due to suboptimal labeling persistence. PMID:25582730

  19. An alternating pressure sequence proposal for an air-cell cushion for preventing pressure ulcers.

    PubMed

    Arias, Sandra; Cardiel, Eladio; Rogeli, Pablo; Mori, Taketoshi; Nakagami, Gojiro; Noguchi, Hiroshi; Sanada, Hiromi

    2014-01-01

    The distribution and release of pressure on ischial regions are two important parameters for evaluating the effectiveness of a cushion; especially the release of pressure over time on ischial tuberosities, which is significant for preventing pressure ulcers. The aim of this work is to evaluate the effect on interface pressure through the application of a proposed alternating pressure sequence for an air-cell cushion. Six healthy volunteers were asked to sit on the air cell cushion, in static and alternating modes, as well as on a typical foam cushion for 12 minutes. Interface pressure was monitored with a matrix sensor system. Interface pressure values on ischial tuberosities, user contact area and pressure distribution were analyzed. Results showed that IP on IT tends to increase in both foam and static cushions, while in alternating cushion IP on IT tends to decrease. User contact area was significantly larger in alternating cushion than in static or foam cushions. Moreover, there is a better pressure re-distribution with alternating cushion than with the other cushions. The goal of the alternating sequence is to redistribute pressure and stimulate the ischial regions in order to promote blood flow and prevent pressure occurring in wheelchair users.

  20. Divergent effects of T cell costimulation and inflammatory cytokine production on autoimmune peripheral neuropathy provoked by Aire deficiency.

    PubMed

    Zeng, Xiaopei L; Nagavalli, Anil; Smith, Colin-Jamal; Howard, James F; Su, Maureen A

    2013-04-15

    Chronic inflammatory demyelinating polyneuropathy results from autoimmune destruction of the peripheral nervous system and is a component of the multiorgan autoimmunity syndrome that results from Aire gene mutations in humans. In parallel, peripheral nervous system autoimmunity resembling chronic inflammatory demyelinating polyneuropathy develops spontaneously in NOD mice with a partial loss of Aire function (NOD.Aire(GW/+) mice) and is a T cell-mediated disease. In this study, we analyze how key aspects of T cell activation and function modulate disease development in Aire-deficient mice. We show that genetic ablation of the Th1 cytokine IFN-γ completely prevents clinical and electrophysiological evidence of neuropathy in NOD.Aire(GW/+) mice. IFN-γ deficiency is associated with absence of immune infiltration and decreased expression of the T cell chemoattractant IP-10 in sciatic nerves. Thus, IFN-γ is absolutely required for the development of autoimmune peripheral neuropathy in NOD.Aire(GW/+) mice. Because IFN-γ secretion is enhanced by B7-CD28 costimulation of T cells, we sought to determine the effects of these costimulatory molecules on neuropathy development. Surprisingly, B7-2 deficiency accelerated neuropathy development in NOD.Aire(GW/+) mice, and Ab blockade of both B7-1 and B7-2 resulted in fulminant, early-onset neuropathy. Thus, in contrast to IFN-γ, B7-2 alone and B7-1/B7-2 in combination function to ameliorate neuropathy development in NOD.Aire(GW/+) mice. Together, these findings reveal distinct and opposing effects of the T cell costimulatory pathway and IFN-γ production on the pathogenesis of autoimmune peripheral neuropathy.

  1. The acute and the long-term effects of nigral lipopolysaccharide administration on dopaminergic dysfunction and glial cell activation.

    PubMed

    Iravani, Mahmoud M; Leung, Clement C M; Sadeghian, Mona; Haddon, Claire O; Rose, Sarah; Jenner, Peter

    2005-07-01

    Sustained reactive microgliosis may contribute to the progressive degeneration of nigral dopaminergic neurons in Parkinson's disease (PD), in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) exposed human and in non-human primates. However, the temporal relationship between glial cell activation and nigral cell death is relatively unexplored. Consequently, the effects of acute (24 h) and chronic (30 days) glial cell activation induced by unilateral supranigral lipopolysaccharide (LPS) administration were studied in rats. At 24 h, LPS administration caused a marked reduction in the number of tyrosine hydroxylase-immunoreactive (TH-ir) neurons in the substantia nigra (SN) but striatal TH-ir was unaffected. By 30 days, the loss of TH-positive neurons in the LPS-treated nigra was no greater than at 24 h although a heterogeneous loss of striatal TH-ir was present. The loss of nigrostriatal neurons was of functional significance, as at 30 days, LPS-treated rats exhibited ipsiversive circling in response to (+)-amphetamine administration. At 24 h, there was a moderate increase in glial fibrillary acidic protein (GFAP)-ir astrocytes in the SN but a marked elevation of p47phox positive OX-42-ir microglia, and intense inducible nitric oxide synthase (iNOS)-ir and 3-nitrotyrosine (3-NT)-ir was present. However, by 30 days the morphology of OX-42-ir microglia returned to a resting state, the numbers were greatly reduced and no 3-NT-ir was present. At 30 days, GFAP-ir astrocytes were markedly increased in number and iNOS-ir was present in fibrillar astrocyte-like cells. This study shows that acute glial activation leading to dopaminergic neuron degeneration is an acute short-lasting response that does not itself perpetuate cell death or lead to prolonged microglial activation.

  2. Specific features of operation of a membrane-electrode assembly of an air-hydrogen fuel cell

    NASA Astrophysics Data System (ADS)

    Nechitailov, A. A.; Glebova, N. V.; Koshkina, D. V.; Tomasov, A. A.; Zelenina, N. K.; Terukova, E. E.

    2013-09-01

    Specific features of the operation of the membrane-electrode assembly with high catalytic activity that are a part of the simplified design of a low-temperature air-hydrogen fuel cell under conditions of forced and natural convection of air on the cathode are studied. The governing effect of water balance on the specific power of the fuel cell in the stationary mode (˜1 h) is shown, and the range of the operating conditions of the cell with self-control is determined. The power of the fuel cell at an efficiency of ˜50% and the surface density of platinum on a cathode of ≈0.2 mg/cm2 is 200-250 and 100 mW/cm2 in the forced and natural air-convection modes, respectively, which is comparable with the advanced results.

  3. Multiple Intravenous Administrations of Human Umbilical Cord Blood Cells Benefit in a Mouse Model of ALS

    PubMed Central

    Garbuzova-Davis, Svitlana; Rodrigues, Maria C. O.; Mirtyl, Santhia; Turner, Shanna; Mitha, Shazia; Sodhi, Jasmine; Suthakaran, Subatha; Eve, David J.; Sanberg, Cyndy D.; Kuzmin-Nichols, Nicole; Sanberg, Paul R.

    2012-01-01

    Background A promising therapeutic strategy for amyotrophic lateral sclerosis (ALS) is the use of cell-based therapies that can protect motor neurons and thereby retard disease progression. We recently showed that a single large dose (25×106 cells) of mononuclear cells from human umbilical cord blood (MNC hUCB) administered intravenously to pre-symptomatic G93A SOD1 mice is optimal in delaying disease progression and increasing lifespan. However, this single high cell dose is impractical for clinical use. The aim of the present pre-clinical translation study was therefore to evaluate the effects of multiple low dose systemic injections of MNC hUCB cell into G93A SOD1 mice at different disease stages. Methodology/Principal Findings Mice received weekly intravenous injections of MNC hUCB or media. Symptomatic mice received 106 or 2.5×106 cells from 13 weeks of age. A third, pre-symptomatic, group received 106 cells from 9 weeks of age. Control groups were media-injected G93A and mice carrying the normal hSOD1 gene. Motor function tests and various assays determined cell effects. Administered cell distribution, motor neuron counts, and glial cell densities were analyzed in mouse spinal cords. Results showed that mice receiving 106 cells pre-symptomatically or 2.5×106 cells symptomatically significantly delayed functional deterioration, increased lifespan and had higher motor neuron counts than media mice. Astrocytes and microglia were significantly reduced in all cell-treated groups. Conclusions/Significance These results demonstrate that multiple injections of MNC hUCB cells, even beginning at the symptomatic disease stage, could benefit disease outcomes by protecting motor neurons from inflammatory effectors. This multiple cell infusion approach may promote future clinical studies. PMID:22319620

  4. CLIMATE CHANGE FUEL CELL PROGRAM UNITED STATES COAST GUARD AIR STATION CAPE COD BOURNE, MASSACHUSETTS

    SciTech Connect

    John K. Steckel Jr

    2004-06-30

    This report covers the first year of operation of a fuel cell power plant, installed by PPL Spectrum, Inc. (PPL) under contract with the United States Coast Guard (USCG), Research and Development Center (RDC). The fuel cell was installed at Air Station Cape Cod in Bourne, MA. The project had the support of the Massachusetts Technology Collaborative (MTC), the Department of Energy (DOE), and Keyspan Energy. PPL selected FuelCell Energy, Inc. (FCE) and its fuel cell model DFC{reg_sign}300 for the contract. Grant contributions were finalized and a contract between PPL and the USCG for the manufacture, installation, and first year's maintenance of the fuel cell was executed on September 24, 2001. As the prime contractor, PPL was responsible for all facets of the project. All the work was completed by PPL through various subcontracts, including the primary subcontract with FCE for the manufacture, delivery, and installation of the fuel cell. The manufacturing and design phases proceeded in a relatively timely manner for the first half of the project. However, during latter stages of manufacture and fuel cell testing, a variety of issues were encountered that ultimately resulted in several delivery delays, and a number of contract modifications. Final installation and field testing was completed in April and May 2003. Final acceptance of the fuel cell was completed on May 16, 2003. The fuel cell has operated successfully for more than one year. The unit achieved an availability rate of 96%, which exceeded expectations. The capacity factor was limited because the unit was set at 155 kW (versus a nameplate of 250 kW) due to the interconnection with the electric utility. There were 18 shutdowns during the first year and most were brief. The ability of this plant to operate in the island mode improved availability by 3 to 4%. Events that would normally be shutdowns were simply island mode events. The mean time between failure was calculated at 239 hours, or slightly less

  5. Administration of cells with thermosensitive hydrogel enhances the functional recovery in ischemic rat heart

    PubMed Central

    Matsushita, Satoshi; Forrester, James S; Li, Chuan; Sato, Mitsuru; Li, Zhengqing; Guo, Xiaolei; Guan, Jianjun; Amano, Atsushi

    2016-01-01

    The lack of cell retention clearly represents a potentially serious limitation for therapeutic efficacy of stem cells. To enhance the efficacy, we developed a novel hydrogel that is thermosensitive and biodegradable and possesses desirable stiffness in a solid form. Immediately after induction of myocardial infarction of male rat, cardiac outgrowth cells embedded in hydrogel (HG) or saline (CO) were injected directly into the peri-infarct area. Left ventricular ejection fraction, cell retention rate, and a spectrum of biochemical markers were measured to evaluate the effect of the treatment. Left ventricular ejection fraction was significantly higher in the cell-injected groups (HG and CO) than in the control group at 1 week after treatment. This functional benefit was continued only in the HG group, accompanied with more retained cells. Furthermore, the expression of insulin-like growth factor-1 was significantly higher in the HG group with less progression of cell apoptosis. PMID:27213036

  6. Errors in measurements of 222Rn in methane and carbon dioxide using scintillation cells calibrated for 222Rn in air.

    PubMed

    Jenkins, Phillip H; Burkhart, James F; Camley, Robert E

    2014-03-01

    Scintillation cells are used typically for measuring the concentration of (222)Rn in air and are calibrated for that purpose. However, scintillation cells are sometimes used for measuring (222)Rn in natural gas or carbon dioxide. The counting efficiencies of scintillation cells for measurements of (222)Rn in these gases should be different from those for measuring (222)Rn in air because the ranges of alpha particles emitted by (222)Rn and its progeny are greater in methane and smaller in carbon dioxide than in air. If these effects are not taken into consideration, measurements of (222)Rn in natural gas will be biased high and in carbon dioxide will be biased low. The authors previously investigated the effects of barometric pressure on measurements of (222)Rn in air using scintillation cells. A modeling technique was used in a previous study to calculate theoretical errors that would result if atmospheric pressure were not considered. In the current study, the same modeling technique was used to calculate theoretical errors that would be made for measurements of (222)Rn in methane and carbon dioxide if the calibration for (222)Rn in air were used. Results are presented for four types of scintillation cells of varying geometries and for barometric pressures representative of four elevations ranging from sea level to 1,963 m (6,440 feet). These results indicate that the errors introduced by the ranges of the alpha particles in gases different from air can be significant. Depending on the type of cell and the local pressure, a measurement of (222)Rn in methane may be biased high by 2-7%, while a measurement of (222)Rn in CO2 may be biased low by 15-20% if the calibration for (222)Rn in air is used. PMID:25208015

  7. Direct detection of salmonella cells in the air of livestock stables by real-time PCR.

    PubMed

    Fallschissel, Kerstin; Kämpfer, Peter; Jäckel, Udo

    2009-11-01

    A SYBR Green real-time quantitative polymerase chain reaction (qPCR) assay for specific detection and quantification of airborne Salmonella cells in livestock housings is presented. A set of specific primers was tested and validated for specific detection and quantification of Salmonella-specific invA genes of DNA extracted from bioaerosol samples. Application of the method to poultry house bioaerosol samples showed concentrations ranging from 2.2 x 10(1) to 3 x 10(6) Salmonella targets m(-3) of air. Salmonella were also detected by a cultivation-based approach in some samples, but concentrations were two to three magnitudes lower than the concentrations detected by molecular biological results. Specificity of results was demonstrated by cloning analyses of PCR products, which were exclusively assigned to the genus Salmonella. However, by molecular methods, microorganisms are detected independently of their viability status, leading to an overestimation of concentration. Hence, the survival rate of Salmonella cells was measured on filter surfaces during filtration samplings where 82% of the cells died within 20 min of filtration. The results clearly show the specificity and practicability of the established qPCR assay for analysis and quantification of salmonellae in bioaerosols. The results demonstrate airborne Salmonella workplace concentrations in poultry production of up to 3.3% of 4',6-Diamidino-2-phenylindole-counted total cell numbers.

  8. Air-breathing direct formic acid microfluidic fuel cell with an array of cylinder anodes

    NASA Astrophysics Data System (ADS)

    Zhu, Xun; Zhang, Biao; Ye, Ding-Ding; Li, Jun; Liao, Qiang

    2014-02-01

    An air-breathing direct formic acid membraneless microfluidic fuel cell using graphite cylinder arrays as the anode is proposed. The three dimensional anode volumetrically extends the reactive surface area and improves fuel utilization. The effects of spacer configuration, fuel and electrolyte concentration as well as reactant flow rate on the species transport and cell performance are investigated. The dynamic behavior of generated CO2 bubbles is visualized and its effect on current generation is discussed. The results show that the absence of two spacers adjacent to the cathode surface improves the cell performance by reducing the proton transfer resistance. The CO2 gas bubbles are constrained within the anode array and expelled by the fluid flow periodically. Proper reactant concentration and flow rate are crucial for cell operation. At optimum conditions, a maximum current density of 118.3 mA cm-3 and a peak power density of 21.5 mW cm-3 are obtained. In addition, benefit from the volumetrically stacked anodes and enhanced fuel transfer, the maximum single pass fuel utilization rate reaches up to 87.6% at the flow rate of 1 mL h-1.

  9. Cubic PdNP-based air-breathing cathodes integrated in glucose hybrid biofuel cells

    NASA Astrophysics Data System (ADS)

    Faggion Junior, D.; Haddad, R.; Giroud, F.; Holzinger, M.; Maduro de Campos, C. E.; Acuña, J. J. S.; Domingos, J. B.; Cosnier, S.

    2016-05-01

    Cubic Pd nanoparticles (PdNPs) were synthesized using ascorbic acid as a reducing agent and were evaluated for the catalytic oxygen reduction reaction. PdNPs were confined with multiwalled carbon nanotube (MWCNT) dispersions to form black suspensions and these inks were dropcast onto glassy carbon electrodes. Different nanoparticle sizes were synthesized and investigated upon oxygen reduction capacities (onset potential and electrocatalytic current densities) under O2 saturated conditions at varying pH values. Strong evidence of O2 diffusion limitation was demonstrated. In order to overcome oxygen concentration and diffusion limitations in solution, we used a gas diffusion layer to create a PdNP-based air-breathing cathode, which delivered -1.5 mA cm-2 at 0.0 V with an onset potential of 0.4 V. This air-breathing cathode was combined with a specially designed phenanthrolinequinone/glucose dehydrogenase-based anode to form a complete glucose/O2 hybrid bio-fuel cell providing an open circuit voltage of 0.554 V and delivering a maximal power output of 184 +/- 21 μW cm-2 at 0.19 V and pH 7.0.Cubic Pd nanoparticles (PdNPs) were synthesized using ascorbic acid as a reducing agent and were evaluated for the catalytic oxygen reduction reaction. PdNPs were confined with multiwalled carbon nanotube (MWCNT) dispersions to form black suspensions and these inks were dropcast onto glassy carbon electrodes. Different nanoparticle sizes were synthesized and investigated upon oxygen reduction capacities (onset potential and electrocatalytic current densities) under O2 saturated conditions at varying pH values. Strong evidence of O2 diffusion limitation was demonstrated. In order to overcome oxygen concentration and diffusion limitations in solution, we used a gas diffusion layer to create a PdNP-based air-breathing cathode, which delivered -1.5 mA cm-2 at 0.0 V with an onset potential of 0.4 V. This air-breathing cathode was combined with a specially designed phenanthrolinequinone

  10. Detection of an autoreactive T-cell population within the polyclonal repertoire that undergoes distinct autoimmune regulator (Aire)-mediated selection.

    PubMed

    Taniguchi, Ruth T; DeVoss, Jason J; Moon, James J; Sidney, John; Sette, Alessandro; Jenkins, Marc K; Anderson, Mark S

    2012-05-15

    The autoimmune regulator (Aire) plays a critical role in central tolerance by promoting the display of tissue-specific antigens in the thymus. To study the influence of Aire on thymic selection in a physiological setting, we used tetramer reagents to detect autoreactive T cells specific for the Aire-dependent tissue-specific antigen interphotoreceptor retinoid-binding protein (IRBP), in the polyclonal repertoire. Two class II tetramer reagents were designed to identify T cells specific for two different peptide epitopes of IRBP. Analyses of the polyclonal T-cell repertoire showed a high frequency of activated T cells specific for both IRBP tetramers in Aire(-/-) mice, but not in Aire(+/+) mice. Surprisingly, although one tetramer-binding T-cell population was efficiently deleted in the thymus in an Aire-dependent manner, the second tetramer-binding population was not deleted and could be detected in both the Aire(-/-) and Aire(+/+) T-cell repertoires. We found that Aire-dependent thymic deletion of IRBP-specific T cells relies on intercellular transfer of IRBP between thymic stroma and bone marrow-derived antigen-presenting cells. Furthermore, our data suggest that Aire-mediated deletion relies not only on thymic expression of IRBP, but also on proper antigen processing and presentation of IRBP by thymic antigen-presenting cells.

  11. Intravenous Administration of Endothelial Colony-Forming Cells Overexpressing Integrin β1 Augments Angiogenesis in Ischemic Legs.

    PubMed

    Goto, Kazuko; Takemura, Genzou; Takahashi, Tomoyuki; Okada, Hideshi; Kanamori, Hiromitsu; Kawamura, Itta; Watanabe, Takatomo; Morishita, Kentaro; Tsujimoto, Akiko; Miyazaki, Nagisa; Ushikoshi, Hiroaki; Kawasaki, Masanori; Mikami, Atsushi; Kosai, Ken-ichiro; Minatoguchi, Shinya

    2016-02-01

    When injected directly into ischemic tissue in patients with peripheral artery disease, the reparative capacity of endothelial progenitor cells (EPCs) appears to be limited by their poor survival. We, therefore, attempted to improve the survival of transplanted EPCs through intravenous injection and gene modification. We anticipated that overexpression of integrin β1 will enable injected EPCs to home to ischemic tissue, which abundantly express extracellular matrix proteins, the ligands for integrins. In addition, integrin β1 has an independent angiogenesis-stimulating function. Human endothelial colony-forming cells (ECFCs; late-outgrowth EPCs) were transduced using a lentiviral vector encoding integrin β1 (ITGB1) or enhanced green fluorescent protein (GFP). We then locally or systemically injected phosphate-buffered saline or the genetically modified ECFCs (GFP-ECFCs or ITGB1-ECFCs; 1 × 10(5) cells each) into NOD/Shi-scid, IL-2Rγnull mice whose right femoral arteries had been occluded 24 hours earlier. Upregulation of extracellular matrix proteins, including fibronectin, was apparent in the ischemic legs. Four weeks later, blood perfusion of the ischemic limb was significantly augmented only in the ITGB1-ECFC group. Scanning electron microscopy of vascular casts revealed increases in the perfused blood vessels in the ischemic legs of mice in the ITGB1-ECFC group and significant increases in the density of both capillaries and arterioles. Transplanted ECFC-derived vessels accounted for 28% ± 4.2% of the vessels in the ITGB1-ECFC group, with no cell fusion. Intravenous administration of ECFCs engineered to home to ischemic tissue appears to efficiently mediate therapeutic angiogenesis in a mouse model of peripheral artery disease. Significance: The intravenous administration of endothelial colony-forming cells (ECFCs) genetically modified to overexpress integrin β1 effectively stimulated angiogenesis in ischemic mouse hindlimbs. Transplanted ECFCs were

  12. Intravenous Administration of Endothelial Colony-Forming Cells Overexpressing Integrin β1 Augments Angiogenesis in Ischemic Legs.

    PubMed

    Goto, Kazuko; Takemura, Genzou; Takahashi, Tomoyuki; Okada, Hideshi; Kanamori, Hiromitsu; Kawamura, Itta; Watanabe, Takatomo; Morishita, Kentaro; Tsujimoto, Akiko; Miyazaki, Nagisa; Ushikoshi, Hiroaki; Kawasaki, Masanori; Mikami, Atsushi; Kosai, Ken-ichiro; Minatoguchi, Shinya

    2016-02-01

    When injected directly into ischemic tissue in patients with peripheral artery disease, the reparative capacity of endothelial progenitor cells (EPCs) appears to be limited by their poor survival. We, therefore, attempted to improve the survival of transplanted EPCs through intravenous injection and gene modification. We anticipated that overexpression of integrin β1 will enable injected EPCs to home to ischemic tissue, which abundantly express extracellular matrix proteins, the ligands for integrins. In addition, integrin β1 has an independent angiogenesis-stimulating function. Human endothelial colony-forming cells (ECFCs; late-outgrowth EPCs) were transduced using a lentiviral vector encoding integrin β1 (ITGB1) or enhanced green fluorescent protein (GFP). We then locally or systemically injected phosphate-buffered saline or the genetically modified ECFCs (GFP-ECFCs or ITGB1-ECFCs; 1 × 10(5) cells each) into NOD/Shi-scid, IL-2Rγnull mice whose right femoral arteries had been occluded 24 hours earlier. Upregulation of extracellular matrix proteins, including fibronectin, was apparent in the ischemic legs. Four weeks later, blood perfusion of the ischemic limb was significantly augmented only in the ITGB1-ECFC group. Scanning electron microscopy of vascular casts revealed increases in the perfused blood vessels in the ischemic legs of mice in the ITGB1-ECFC group and significant increases in the density of both capillaries and arterioles. Transplanted ECFC-derived vessels accounted for 28% ± 4.2% of the vessels in the ITGB1-ECFC group, with no cell fusion. Intravenous administration of ECFCs engineered to home to ischemic tissue appears to efficiently mediate therapeutic angiogenesis in a mouse model of peripheral artery disease. Significance: The intravenous administration of endothelial colony-forming cells (ECFCs) genetically modified to overexpress integrin β1 effectively stimulated angiogenesis in ischemic mouse hindlimbs. Transplanted ECFCs were

  13. Response of hemopoietic, progenitor, and multipotent mesenchymal stromal cells to administration of ketanserin during pulmonary fibrosis.

    PubMed

    Dygai, A M; Skurikhin, E G; Pershina, O V; Stepanova, I E; Khmelevskaya, E S; Ermakova, N N; Reztsova, A M; Krupin, V A; Reikhart, D V; Goldberg, V E

    2014-11-01

    We studied the effect of ketanserin on hemopoietic progenitor cells (Lin(-)Sca-1(+)c-Kit(+)CD34- and Lin(-)Sca-1(+)c-Kit(+)CD34(+)), progenitor hemopoietic cells (Lin(-)Sca-1(+)c-kit(+)), and multipotent mesenchymal stromal cells (CD45(-)CD73(+)CD106(+)) in C57Bl/6 mice during pulmonary fibrosis. It was shown that the blocker of 5-HT2A receptors lowers the activity of bleomycin-induced inflammation in the lungs and prevents the infiltration of alveolar interstitium and alveolar ducts by hemopoietic stem and hemopoietic progenitor cells; in this case, they are more numerous in the bone marrow of sick animals. Ketanserin reduces the capacity for self-renewal of lung multipotent mesenchymal stromal cells in the fibrotic phase of the disease and inhibits their differentiation into stromal cell lines (adipocytes, chondrocytes, and fibroblasts) simultaneously with the decrease in the percentage of connective tissue in the lung parenchyma. PMID:25403389

  14. UCB Transplant of Inherited Metabolic Diseases With Administration of Intrathecal UCB Derived Oligodendrocyte-Like Cells

    ClinicalTrials.gov

    2016-07-27

    Adrenoleukodystrophy; Batten Disease; Mucopolysaccharidosis II; Leukodystrophy, Globoid Cell; Leukodystrophy, Metachromatic; Neimann Pick Disease; Pelizaeus-Merzbacher Disease; Sandhoff Disease; Tay-Sachs Disease; Brain Diseases, Metabolic, Inborn

  15. Influence of common cold and of parenteral administration of influenza virus antigens on bronchoalveolar lavage cells.

    PubMed

    Demedts, M; Van den Eeckhout, A; Neirynck, J; Mariën, G; Ceuppens, J L

    1986-04-01

    We investigated in a pilot study on healthy young subjects whether a common cold or a vaccination with influenza virus antigens within 10 days influenced the number and subsets of inflammatory cells in the bronchoalveolar lavage (BAL) fluid. The total number of BAL-cells was about doubled in the common cold group, yet no consistent changes in overall cell distribution was found. Among BAL-lymphocytes the ratio of helper-inducer over suppressor-cytotoxic lymphocytes (THI/TCS) tended to be increased in both groups, due to a lower percentage of TCS-cells, which was significant in the vaccination group only. In the blood, on the contrary, the THI/TCS ratio was significantly decreased in both groups due to a drop in THI-cells; in addition, the proportions of E-Rosette (+) T-cells and of activated (Ia+) T-cells were slightly increased. In conclusion, only minor changes in inflammatory BAL-cells were observed, which, however, may interfere with the effects of other diseases.

  16. Defective central tolerance in Aire-deficient mice is not sufficient to induce symptomatic autoimmunity during lymphopenia-induced T cell proliferation.

    PubMed

    Kekäläinen, E; Lehto, M-K; Smeds, E; Miettinen, A; Meri, S; Jarva, H; Arstila, T Petteri

    2011-07-01

    Transcriptional regulator autoimmune regulator (AIRE) controls thymic negative selection but it is also expressed in secondary lymphoid organs. The relative contribution of AIRE's central and peripheral function to the maintenance of tolerance is unclear. We transferred mature lymphocytes from Aire(-/-) or wild-type donors to Aire(+/+) lymphopenic recipients, which allowed us to gauge the autoreactivity inherent in the cells originating in an Aire(-/-) thymus. In the ensuing lymphopenia-induced proliferation (LIP), the recipients of cells from Aire(-/-) showed definite T cell hyperproliferation and developed autoantibodies at a higher frequency than the recipients of wild-type cells. However, neither of the recipient groups developed clinical symptoms, and pathological tissue infiltrates were also absent. The recipients of Aire(-/-) cells showed hyperproliferation and increased accumulation of regulatory T cells (Tregs), especially in tissues susceptible to inflammation triggered by LIP. These data are consistent with the view that T cells developing in the absence of Aire are autoreactive. However, overt autoimmunity was prevented, most likely by the suppressive function of Treg cells in the Aire-sufficient recipients. Our results support the importance of the peripheral AIRE expression in the maintenance of immunological tolerance.

  17. Effects of hydraulic pressure on the performance of single chamber air-cathode microbial fuel cells.

    PubMed

    Cheng, Shaoan; Liu, Weifeng; Guo, Jian; Sun, Dan; Pan, Bin; Ye, Yaoli; Ding, Weijun; Huang, Haobin; Li, Fujian

    2014-06-15

    Scaling up of microbial fuel cells (MFCs) without losing power density requires a thorough understanding of the effect of hydraulic pressure on MFC performance. In this work, the performance of an activated carbon air-cathode MFC was evaluated under different hydraulic pressures. The MFC under 100 mmH2O hydraulic pressure produced a maximum power density of 1260 ± 24 mW m(-2), while the power density decreased by 24.4% and 44.7% as the hydraulic pressure increased to 500 mmH2O and 2000 mmH2O, respectively. Notably, the performance of both the anode and the cathode had decreased under high hydraulic pressures. Electrochemical impedance spectroscopy tests of the cathode indicated that both charge transfer resistance and diffusion transfer resistance increased with the increase in hydraulic pressure. Denaturing gradient gel electrophoresis of PCR-amplified partial 16S rRNA genes demonstrated that the similarity among anodic biofilm communities under different hydraulic pressures was ≥ 90%, and the communities of all MFCs were dominated by Geobacter sp. These results suggested that the reduction in power output of the single chamber air-cathode MFC under high hydraulic pressures can be attributed to water flooding of the cathode and suppression the metabolism of anodic exoelectrogenic bacteria.

  18. Acoustical transmission-line model of the middle-ear cavities and mastoid air cells.

    PubMed

    Keefe, Douglas H

    2015-04-01

    An acoustical transmission line model of the middle-ear cavities and mastoid air cell system (MACS) was constructed for the adult human middle ear with normal function. The air-filled cavities comprised the tympanic cavity, aditus, antrum, and MACS. A binary symmetrical airway branching model of the MACS was constructed using an optimization procedure to match the average total volume and surface area of human temporal bones. The acoustical input impedance of the MACS was calculated using a recursive procedure, and used to predict the input impedance of the middle-ear cavities at the location of the tympanic membrane. The model also calculated the ratio of the acoustical pressure in the antrum to the pressure in the middle-ear cavities at the location of the tympanic membrane. The predicted responses were sensitive to the magnitude of the viscothermal losses within the MACS. These predicted input impedance and pressure ratio functions explained the presence of multiple resonances reported in published data, which were not explained by existing MACS models.

  19. Acoustical transmission-line model of the middle-ear cavities and mastoid air cells

    PubMed Central

    Keefe, Douglas H.

    2015-01-01

    An acoustical transmission line model of the middle-ear cavities and mastoid air cell system (MACS) was constructed for the adult human middle ear with normal function. The air-filled cavities comprised the tympanic cavity, aditus, antrum, and MACS. A binary symmetrical airway branching model of the MACS was constructed using an optimization procedure to match the average total volume and surface area of human temporal bones. The acoustical input impedance of the MACS was calculated using a recursive procedure, and used to predict the input impedance of the middle-ear cavities at the location of the tympanic membrane. The model also calculated the ratio of the acoustical pressure in the antrum to the pressure in the middle-ear cavities at the location of the tympanic membrane. The predicted responses were sensitive to the magnitude of the viscothermal losses within the MACS. These predicted input impedance and pressure ratio functions explained the presence of multiple resonances reported in published data, which were not explained by existing MACS models. PMID:25920840

  20. A single-chamber microbial fuel cell without an air cathode.

    PubMed

    Nimje, Vanita Roshan; Chen, Chien-Cheng; Chen, Hau-Ren; Chen, Chien-Yen; Tseng, Min-Jen; Cheng, Kai-Chien; Shih, Ruey-Chyuan; Chang, Young-Fo

    2012-01-01

    Microbial fuel cells (MFCs) represent a novel technology for wastewater treatment with electricity production. Electricity generation with simultaneous nitrate reduction in a single-chamber MFC without air cathode was studied, using glucose (1 mM) as the carbon source and nitrate (1 mM) as the final electron acceptor employed by Bacillus subtilis under anaerobic conditions. Increasing current as a function of decreased nitrate concentration and an increase in biomass were observed with a maximum current of 0.4 mA obtained at an external resistance (R(ext)) of 1 KΩ without a platinum catalyst of air cathode. A decreased current with complete nitrate reduction, with further recovery of the current immediately after nitrate addition, indicated the dependence of B. subtilis on nitrate as an electron acceptor to efficiently produce electricity. A power density of 0.0019 mW/cm(2) was achieved at an R(ext) of 220 Ω. Cyclic voltammograms (CV) showed direct electron transfer with the involvement of mediators in the MFC. The low coulombic efficiency (CE) of 11% was mainly attributed to glucose fermentation. These results demonstrated that electricity generation is possible from wastewater containing nitrate, and this represents an alternative technology for the cost-effective and environmentally benign treatment of wastewater.

  1. Cubic PdNP-based air-breathing cathodes integrated in glucose hybrid biofuel cells.

    PubMed

    Faggion Junior, D; Haddad, R; Giroud, F; Holzinger, M; Maduro de Campos, C E; Acuña, J J S; Domingos, J B; Cosnier, S

    2016-05-21

    Cubic Pd nanoparticles (PdNPs) were synthesized using ascorbic acid as a reducing agent and were evaluated for the catalytic oxygen reduction reaction. PdNPs were confined with multiwalled carbon nanotube (MWCNT) dispersions to form black suspensions and these inks were dropcast onto glassy carbon electrodes. Different nanoparticle sizes were synthesized and investigated upon oxygen reduction capacities (onset potential and electrocatalytic current densities) under O2 saturated conditions at varying pH values. Strong evidence of O2 diffusion limitation was demonstrated. In order to overcome oxygen concentration and diffusion limitations in solution, we used a gas diffusion layer to create a PdNP-based air-breathing cathode, which delivered -1.5 mA cm(-2) at 0.0 V with an onset potential of 0.4 V. This air-breathing cathode was combined with a specially designed phenanthrolinequinone/glucose dehydrogenase-based anode to form a complete glucose/O2 hybrid bio-fuel cell providing an open circuit voltage of 0.554 V and delivering a maximal power output of 184 ± 21 μW cm(-2) at 0.19 V and pH 7.0. PMID:27142300

  2. Silver electrodeposition on the activated carbon air cathode for performance improvement in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Pu, Liangtao; Li, Kexun; Chen, Zhihao; Zhang, Peng; Zhang, Xi; Fu, Zhou

    2014-12-01

    The present work was to study silver electrodeposition on the activated carbon (AC) air cathode for performance improvement in microbial fuel cells (MFCs). The treated cathodes were proved to be effective to enhance the performance of MFCs. The maximum power density of MFC with silver electrodeposition time of 50 s (Ag-50) cathode was 1080 ± 60 mW m-2, 69% higher than the bare AC air cathode. X-ray photoelectron spectroscopy (XPS) results showed that zero-valent, monovalent and divalent silver were present to transform mutually, which illustrated that the oxygen reduction reaction (ORR) at the cathode took place through four-electron pathway. From electrochemical impedance spectroscopy (EIS) analysis, the electrodeposition method made the total resistance of the electrodes largely reduced. Meanwhile the deposited silver had no toxic effects on anode culture but inhibited the biofilm growth of the cathodes. This kind of antimicrobial efficient cathode, prepared with a simple, fast and economical method, was of good benefit to the performance improvement of MFCs.

  3. Induction of regulatory T cells in Th1-/Th17-driven experimental autoimmune encephalomyelitis by zinc administration.

    PubMed

    Rosenkranz, Eva; Maywald, Martina; Hilgers, Ralf-Dieter; Brieger, Anne; Clarner, Tim; Kipp, Markus; Plümäkers, Birgit; Meyer, Sören; Schwerdtle, Tanja; Rink, Lothar

    2016-03-01

    The essential trace element zinc is indispensable for proper immune function as zinc deficiency accompanies immune defects and dysregulations like allergies, autoimmunity and an increased presence of transplant rejection. This point to the importance of the physiological and dietary control of zinc levels for a functioning immune system. This study investigates the capacity of zinc to induce immune tolerance. The beneficial impact of physiological zinc supplementation of 6 μg/day (0.3mg/kg body weight) or 30 μg/day (1.5mg/kg body weight) on murine experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis with a Th1/Th17 (Th, T helper) cell-dominated immunopathogenesis, was analyzed. Zinc administration diminished EAE scores in C57BL/6 mice in vivo (P<.05), reduced Th17 RORγT(+) cells (P<.05) and significantly increased inducible iTreg cells (P<.05). While Th17 cells decreased systemically, iTreg cells accumulated in the central nervous system. Cumulatively, zinc supplementation seems to be capable to induce tolerance in unwanted immune reactions by increasing iTreg cells. This makes zinc a promising future tool for treating autoimmune diseases without suppressing the immune system.

  4. In-situ administration of dendritic cells following argon-helium cryosurgery enhances specific antiglioma immunity in mice.

    PubMed

    Lin, Chunnan; Wang, Qifu; Lu, Guohui; Yin, Zhilin; He, Xiaozheng; Xu, Hongchao; Pan, Jun; Zhang, Shizhong

    2014-08-20

    Dendritic cells (DCs) are highly specialized antigen-presenting cells that play a key role in the activation of naive T cells. With an aim to explore whether in-situ administration of DCs following argon-helium cryosurgery could enhance specific antiglioma immunity in mice, we evaluated the validity of this approach in a murine subcutaneous GL261 glioma model. C57BL/6 mice models bearing subcutaneous GL261 glioma were established and then divided into four groups, namely, no-treatment group (n=14), DC group (n=14), cryosurgery group (n=15), and cryosurgery+DC group (n=15). Compared with the other groups, cryosurgery combined with DCs injection reduced tumor sizes and significantly prolonged survival. In addition, the combined treatment resulted in significantly increasing percentages of CD3, CD3CD4 cells, the ratio of CD3CD4/CD3CD8, and the level of serum interleukin-12 10 days after treatments. Furthermore, in the combined treatment group, Th1 cells were significantly higher than those in the other groups, and the splenic cytotoxic T lymphocyte of mice showed significantly increasing specific cytotoxicity against GL261 cells. These results indicated that in addition to the destruction of tumor, cryosurgery combined with DCs injection enhanced systemic antitumor immunity, suggesting the potential usefulness of the combined treatment in the clinical management of gliomas.

  5. Impairment of the Anterior Thalamic Head Direction Cell Network Following Administration of the NMDA antagonist MK-801

    PubMed Central

    Housh, Adam A.; Berkowitz, Laura E.; Ybarra, Isaac; Kim, Esther U.; Lee, Brian R.; Calton, Jeffrey L.

    2014-01-01

    Head direction (HD) cells, found in the rodent Papez circuit, are thought to form the neural circuitry responsible for directional orientation. Because NMDA transmission has been implicated in spatial tasks requiring directional orientation, we sought to determine if the NMDA antagonist dizocilpine (MK-801) would disrupt the directional signal carried by the HD network. Anterior thalamic HD cells were isolated in female Long-Evans rats and initially monitored for baseline directional activity while the animals foraged in a familiar enclosure. The animals were then administered MK-801 at a dose of .05 mg/kg or 0.1 mg/kg, or isotonic saline, and cells were re-examined for changes in directional specificity and landmark control. While the cells showed no changes in directional specificity and landmark control following administration of saline or the lower dose of MK-801, the higher dose of MK-801 caused a dramatic attenuation of the directional signal, characterized by decreases in peak firing rates, signal to noise, and directional information content. While the greatly attenuated directional specificity of cells in the high dose condition usually remained stable relative to the landmarks within the recording enclosure, a few cells in this condition exhibited unstable preferred directions within and between recording sessions. Our results are discussed relative to the possibility that the findings explain the effects of MK-801 on the acquisition and performance of spatial tasks. PMID:25307435

  6. Improved air stability of perovskite solar cells via solution-processed metal oxide transport layers.

    PubMed

    You, Jingbi; Meng, Lei; Song, Tze-Bin; Guo, Tzung-Fang; Yang, Yang Michael; Chang, Wei-Hsuan; Hong, Ziruo; Chen, Huajun; Zhou, Huanping; Chen, Qi; Liu, Yongsheng; De Marco, Nicholas; Yang, Yang

    2016-01-01

    Lead halide perovskite solar cells have recently attracted tremendous attention because of their excellent photovoltaic efficiencies. However, the poor stability of both the perovskite material and the charge transport layers has so far prevented the fabrication of devices that can withstand sustained operation under normal conditions. Here, we report a solution-processed lead halide perovskite solar cell that has p-type NiO(x) and n-type ZnO nanoparticles as hole and electron transport layers, respectively, and shows improved stability against water and oxygen degradation when compared with devices with organic charge transport layers. Our cells have a p-i-n structure (glass/indium tin oxide/NiO(x)/perovskite/ZnO/Al), in which the ZnO layer isolates the perovskite and Al layers, thus preventing degradation. After 60 days storage in air at room temperature, our all-metal-oxide devices retain about 90% of their original efficiency, unlike control devices made with organic transport layers, which undergo a complete degradation after just 5 days. The initial power conversion efficiency of our devices is 14.6 ± 1.5%, with an uncertified maximum value of 16.1%.

  7. Improved air stability of perovskite solar cells via solution-processed metal oxide transport layers

    NASA Astrophysics Data System (ADS)

    You, Jingbi; Meng, Lei; Song, Tze-Bin; Guo, Tzung-Fang; Yang, Yang (Michael); Chang, Wei-Hsuan; Hong, Ziruo; Chen, Huajun; Zhou, Huanping; Chen, Qi; Liu, Yongsheng; De Marco, Nicholas; Yang, Yang

    2016-01-01

    Lead halide perovskite solar cells have recently attracted tremendous attention because of their excellent photovoltaic efficiencies. However, the poor stability of both the perovskite material and the charge transport layers has so far prevented the fabrication of devices that can withstand sustained operation under normal conditions. Here, we report a solution-processed lead halide perovskite solar cell that has p-type NiOx and n-type ZnO nanoparticles as hole and electron transport layers, respectively, and shows improved stability against water and oxygen degradation when compared with devices with organic charge transport layers. Our cells have a p-i-n structure (glass/indium tin oxide/NiOx/perovskite/ZnO/Al), in which the ZnO layer isolates the perovskite and Al layers, thus preventing degradation. After 60 days storage in air at room temperature, our all-metal-oxide devices retain about 90% of their original efficiency, unlike control devices made with organic transport layers, which undergo a complete degradation after just 5 days. The initial power conversion efficiency of our devices is 14.6 ± 1.5%, with an uncertified maximum value of 16.1%.

  8. Computational modeling of alkaline air-breathing microfluidic fuel cells with an array of cylinder anodes

    NASA Astrophysics Data System (ADS)

    Ye, Ding-Ding; Zhang, Biao; Zhu, Xun; Sui, Pang-Chieh; Djilali, Ned; Liao, Qiang

    2015-08-01

    A three-dimensional computational model is developed for an alkaline air-breathing microfluidic fuel cell (AMFC) with an array of cylinder anodes. The model is validated against experimental data from an in-house prototype AMFC. The distributions of fluid velocity, fuel concentration and current density of the fuel cell are analyzed in detail. The effect of reactant flow rate on the cell performance and electrode potentials is also studied. The model results suggest that fuel crossover is minimized by the fast electrolyte flow in the vicinity of the cathode. The current production of each anode is uneven and is well correlated with internal ohmic resistance. Fuel transfer limitation occurs at low flow rates (<100 μL min-1) but diminishes at high flow rates. The model results also indicate that cathode potential reversal takes place at combined low flow rate and high current density conditions, mainly due to the improved overpotential downstream where fuel starvation occurs. The anode reaction current distribution is found to be relatively uniform, which is a result of a compensating mechanism that improves the current production of the bottom anodes downstream.

  9. NanoCapillary Network Proton Conducting Membranes for High Temperature Hydrogen/Air Fuel Cells

    SciTech Connect

    Pintauro, Peter

    2012-07-09

    The objective of this proposal is to fabricate and characterize a new class of NanoCapillary Network (NCN) proton conducting membranes for hydrogen/air fuel cells that operate under high temperature, low humidity conditions. The membranes will be intelligently designed, where a high density interconnecting 3-D network of nm-diameter electrospun proton conducting polymer fibers is embedded in an inert (uncharged) water/gas impermeable polymer matrix. The high density of fibers in the resulting mat and the high ion-exchange capacity of the fiber polymer will ensure high proton conductivity. To further enhance water retention, molecular silica will be added to the sulfonated polymer fibers. The uncharged matrix material will control water swelling of the high ion-exchange capacity proton conducting polymer fibers and will impart toughness to the final nanocapillary composite membrane. Thus, unlike other fuel cell membranes, the role of the polymer support matrix will be decoupled from that of the proton-conducting channels. The expected final outcome of this 5-year project is the fabrication of fuel cell membranes with properties that exceed the DOE’s technical targets, in particular a proton conductivity of 0.1 S/cm at a temperature less than or equal to120°C and 25-50% relative humidity.

  10. [Electricity generation using the short-arm air-cathode microbial fuel cell].

    PubMed

    Guo, Kun; Li, Ding-jie; Li, Hao-ran; Du, Zhu-wei

    2009-10-15

    The short-arm air-cathode microbial fuel cell (ACMFC) was constructed using a cramp to fix the proton exchange membrane (PEM) and carbon paper with 0.5 mg/cm2 onto the short-arm side of the anode chamber. Exoelectrogens on the surface of graphite rod were enriched by a sludge microbial fuel cell from the anaerobic digestion sludge. And the cyclic voltammetry result showed these microbes had electrochemical activities. Using the graphite rod covered by exoelectrogens as the anode and sodium acetate as the substrate, the short-arm ACMFC showed a maximal power density (Pm) of 738 mW/m2, internal resistance (Ri) of 280 omega and open circuit voltage (OCV) of 741 mV. Continuous sparging the anode chamber with nitrogen or removal of the proton exchange membrane enhance the Pm of the cell to 745 mW/m2 and 759 mW/m2 respectively. When both of the two measures were used together, the Pm reached up to 922 mW/m2. Under these three conditions the Ri of the cell was kept around 280 omega. When the substrate concentration was 12.62-100.96 mg/L and external resistance was 510 omega, the maximal voltage of the cell and the substrate concentration showed an obvious linear relation (R2 = 0.99). But when the concentration was above 100.96 mg/L, the maximal voltage stably kept around 302mV(the external resistance was 510 omega). However, the Coulombic efficiency of the short-arm ACMFC gradually increased with the increase of the substrate concentration, from 31.83% to 45.03%.

  11. Repetitive busulfan administration after hematopoietic stem cell gene therapy associated with a dominant HDAC7 clone in a nonhuman primate.

    PubMed

    Xie, Jianjun; Larochelle, Andre; Maric, Irina; Faulhaber, Marion; Donahue, Robert E; Dunbar, Cynthia E

    2010-06-01

    The risk of genotoxicity of retroviral vector-delivered gene therapy targeting hematopoietic stem cells (HSCs) has been highlighted by the development of clonal dominance and malignancies in human and animal gene therapy trials. Large-animal models have proven invaluable to test the safety of retroviral vectors, but the detection of clonal dominance may require years of follow-up. We hypothesized that hematopoietic stress may accelerate the proliferation and therefore the detection of abnormal clones in these models. We administered four monthly busulfan (Bu) infusions to induce hematopoietic stress in a healthy rhesus macaque previously transplanted with CD34+ cells transduced with retroviral vectors carrying a simple marker gene. Busulfan administration resulted in significant cytopenias with each cycle, and prolonged pancytopenia after the final cycle with eventual recovery. Before busulfan treatment there was highly polyclonal marking in all lineages. After Bu administration clonal diversity was markedly decreased in all lineages. Unexpectedly, we found no evidence of selection of the MDS1/EVI1 clones present before Bu administration, but a clone with a vector integration in intron 1 of the histone deacetylase-7 (HDAC7) gene became dominant in granulocytes over time after Bu administration. The overall marking level in the animal was increased significantly after Bu treatment and coincident with expansion of the HDAC7 clone, suggesting an in vivo advantage for this clone under stress. HDAC7 expression was upregulated in marrow progenitors containing the vector. Almost 5 years after Bu administration, the animal developed progressive cytopenias, and at autopsy the marrow showed complete lack of neutrophil or platelet maturation, with a new population of approximately 20% undifferentiated blasts. These data suggest that chemotherapeutic stress may accelerate vector-related clonal dominance, even in the absence of drug resistance genes expressed by the vector

  12. Systemic administration of antigen-pulsed dendritic cells induces experimental allergic asthma in mice upon aerosol antigen rechallenge.

    PubMed

    Graffi, Sebastian J; Dekan, Gerhard; Stingl, Georg; Epstein, Michelle M

    2002-05-01

    Antigen-pulsed dendritic cells (DCs) have been used extensively as cellular vaccines to induce a myriad of protective immune responses. Adoptive transfer of antigen-pulsed DCs is especially effective at generating Th1 and CD8 immune responses. However, recently this strategy has been shown to induce Th2 cells when DCs are administered locally into the respiratory tract. We sought to address whether systemic rather than local antigen-pulsed DC administration could induce Th2 experimental allergic asthma. We found that OVA-pulsed splenic DCs injected intraperitoneally induced polarized Th2 allergic lung disease upon secondary OVA aerosol challenge. Disease was characterized by eosinophilic lung inflammation, excess mucus production, airway hyperresponsiveness, and OVA-specific IgG1 and IgE. In addition, unusual pathology characterized by macrophage alveolitis and multinucleated giant cells was observed. These data show that systemic administration of antigen-pulsed DCs and subsequent aeroantigen challenge induces Th2 immunity. These findings have important implications for the development of DC-based vaccines.

  13. The expression of cyclic adenosine monophosphate responsive element modulator in rat sertoli cells following seminal extract administration

    PubMed Central

    Akmal, Muslim; Siregar, Tongku Nizwan; Wahyuni, Sri; Hamny; Nasution, Mustafa Kamal; Indriati, Wiwik; Panjaitan, Budianto; Aliza, Dwinna

    2016-01-01

    Aim: This study aims to determine the effect of seminal vesicle extract on cyclic adenosine monophosphate responsive element modulator (CREM) expression in rat Sertoli cells. Materials and Methods: This study examined the expression of CREM on 20 male rats (Rattus norvegicus) at 4 months of age, weighing 250-300 g. The rats were divided into four groups: K0, KP1, KP2, and KP3. K0 group was injected with 0.2 ml normal saline; KP1 was injected with 25 mg cloprostenol (Prostavet C, Virbac S. A); KP2 and KP3 were injected with 0.2 and 0.4 ml seminal vesicle extract, respectively. The treatments were conducted 5 times within 12-day interval. At the end of the study, the rats were euthanized by cervical dislocation; then, the testicles were necropsied and processed for histology observation using immunohistochemistry staining. Results: CREM expression in rat Sertoli cells was not altered by the administration of either 0.2 or 0.4 ml seminal vesicle extract. Conclusion: The administration of seminal vesicle extract is unable to increase CREM expression in rat Sertoli cells. PMID:27733803

  14. Cleaning the Air and Improving Health with Hydrogen Fuel-Cell Vehicles

    NASA Astrophysics Data System (ADS)

    Jacobson, M. Z.; Colella, W. G.; Golden, D. M.

    2005-06-01

    Converting all U.S. onroad vehicles to hydrogen fuel-cell vehicles (HFCVs) may improve air quality, health, and climate significantly, whether the hydrogen is produced by steam reforming of natural gas, wind electrolysis, or coal gasification. Most benefits would result from eliminating current vehicle exhaust. Wind and natural gas HFCVs offer the greatest potential health benefits and could save 3700 to 6400 U.S. lives annually. Wind HFCVs should benefit climate most. An all-HFCV fleet would hardly affect tropospheric water vapor concentrations. Conversion to coal HFCVs may improve health but would damage climate more than fossil/electric hybrids. The real cost of hydrogen from wind electrolysis may be below that of U.S. gasoline.

  15. Cleaning the air and improving health with hydrogen fuel-cell vehicles.

    PubMed

    Jacobson, M Z; Colella, W G; Golden, D M

    2005-06-24

    Converting all U.S. onroad vehicles to hydrogen fuel-cell vehicles (HFCVs) may improve air quality, health, and climate significantly, whether the hydrogen is produced by steam reforming of natural gas, wind electrolysis, or coal gasification. Most benefits would result from eliminating current vehicle exhaust. Wind and natural gas HFCVs offer the greatest potential health benefits and could save 3700 to 6400 U.S. lives annually. Wind HFCVs should benefit climate most. An all-HFCV fleet would hardly affect tropospheric water vapor concentrations. Conversion to coal HFCVs may improve health but would damage climate more than fossil/electric hybrids. The real cost of hydrogen from wind electrolysis may be below that of U.S. gasoline.

  16. Investigation on the heavy-metal content of zinc-air button cells.

    PubMed

    Richter, Andrea; Richter, Silke; Recknagel, Sebastian

    2008-01-01

    Within the framework of a German government project (initiated by the Federal Environment Agency) to check the compliance of commercially available batteries with the German Battery Ordinance concerning their heavy metal contents, 18 different types of commercially available zinc-air button cells were analysed for their cadmium, lead and mercury contents. After microwave assisted dissolution with aqua regia, Cd and Pb were determined using inductively coupled plasma mass spectrometry (ICP-MS), and Hg was determined using inductively coupled plasma optical emission spectrometry (ICP OES) and atomic absorption spectrometry. Cd contents were found to be much lower than the permitted limits; Pb contents were also found to be below the limits. Hg contents were found to be near the limits, and in one case the limit was exceeded. PMID:18280730

  17. Inactivation of Escherichia coli Cells in Aqueous Solution by Atmospheric-Pressure N2, He, Air, and O2 Microplasmas

    PubMed Central

    Zhou, Renwu; Zhang, Xianhui; Bi, Zhenhua; Zong, Zichao; Niu, Jinhai; Song, Ying; Yang, Size

    2015-01-01

    Atmospheric-pressure N2, He, air, and O2 microplasma arrays have been used to inactivate Escherichia coli cells suspended in aqueous solution. Measurements show that the efficiency of inactivation of E. coli cells is strongly dependent on the feed gases used, the plasma treatment time, and the discharge power. Compared to atmospheric-pressure N2 and He microplasma arrays, air and O2 microplasma arrays may be utilized to more efficiently kill E. coli cells in aqueous solution. The efficiencies of inactivation of E. coli cells in water can be well described by using the chemical reaction rate model, where reactive oxygen species play a crucial role in the inactivation process. Analysis indicates that plasma-generated reactive species can react with E. coli cells in water by direct or indirect interactions. PMID:26025895

  18. Inactivation of Escherichia coli Cells in Aqueous Solution by Atmospheric-Pressure N2, He, Air, and O2 Microplasmas.

    PubMed

    Zhou, Renwu; Zhang, Xianhui; Bi, Zhenhua; Zong, Zichao; Niu, Jinhai; Song, Ying; Liu, Dongping; Yang, Size

    2015-08-01

    Atmospheric-pressure N2, He, air, and O2 microplasma arrays have been used to inactivate Escherichia coli cells suspended in aqueous solution. Measurements show that the efficiency of inactivation of E. coli cells is strongly dependent on the feed gases used, the plasma treatment time, and the discharge power. Compared to atmospheric-pressure N2 and He microplasma arrays, air and O2 microplasma arrays may be utilized to more efficiently kill E. coli cells in aqueous solution. The efficiencies of inactivation of E. coli cells in water can be well described by using the chemical reaction rate model, where reactive oxygen species play a crucial role in the inactivation process. Analysis indicates that plasma-generated reactive species can react with E. coli cells in water by direct or indirect interactions.

  19. The size of the mastoid air cell system among black and white children with middle ear effusion.

    PubMed

    Lindeman, P; Holmquist, J; Shea, J

    1981-09-01

    The incidence of middle ear disease among black American children is lower than among white children. Many factors may contribute to this difference. The possibility of an anatomical variation regarding the cellularity of the mastoid process was investigated. The size of the mastoid air cell system was measured in black and white children with and without middle ear effusion. A significantly smaller mastoid air cell system was found in the groups with middle ear disease compared to those without disease. No difference between white and black children in diseased as well as non-diseased ears could be demonstrated. PMID:7319703

  20. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... environmental cell test data for the range of vehicles to be covered by the simulation including items such as the tailpipe emissions, air conditioning compressor load, and fuel economy. (2) For any...

  1. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... environmental cell test data for the range of vehicles to be covered by the simulation including items such as the tailpipe emissions, air conditioning compressor load, and fuel economy. (2) For any...

  2. Tennessee Valley Authority/Bonneville Power Administration Indoor Air Quality Study, Phase II : Final Report for Indoor Air Quality Studies Conducted by TVA During Winters 1983, 1984, and 1985.

    SciTech Connect

    Tennessee Valley Authority. Energy Use Test Facility Staff.

    1985-12-01

    This study expanded the existing data base on indoor-outdoor air quality and provided specific information on the use of wood-burning heaters in a weatherized home having a low air exchange rate. Through research efforts such as these, BPA continues to address the various concerns raised regarding environmental issues related to its conservtion programs.

  3. The administration of demethyl fruticulin A from Salvia corrugata to mammalian cells lines induces "anoikis", a special form of apoptosis.

    PubMed

    Giannoni, Paolo; Narcisi, Roberto; De Totero, Daniela; Romussi, Giovanni; Quarto, Rodolfo; Bisio, Angela

    2010-05-01

    Recently demethyl fruticulin A was identified as the major diterpenoid component of the exudates produced by the trichomes of Salvia corrugata leafs. Given the documented apoptotic effects of some of the other known components of the exudates from Salvia species, we assessed if demethyl fruticulin A, once administered to mammalian cells, was involved in the onset of apoptosis and if its biological effects were exerted through the participation of a scavenger membrane receptor, CD36. Three model cell lines were chosen, one of which lacking CD36 expression. Functional availability of the receptor, or its transcriptional rate, were blocked/reduced with a specific antibody or by the administration of vitamin E. Immunodetection of cell cytoskeletal components and tunel analysis revealed that demethyl fruticulin A triggers the onset of anoikis, a special form of apoptosis induced by cell detachment from the substrate. Impairment of CD36 availability/transcription confirmed the receptor partial involvement in the intake of the substance and in anoikis, as also sustained by FACS analysis and by the downregulation of p95, a marker of anoikis, upon blockade of CD36 transcription. However, experiments with CD36-deficient cells suggested that alternate pathways, still to be determined, may take part in the biological effects exerted by demethyl fruticulin A.

  4. Vibriocidal activity, immune globulin producing cells and immune globulin levels in Theropithecus gelada after administration of a Vibrio cholerae antigen

    PubMed Central

    Felsenfeld, Oscar; Greer, William E.

    1968-01-01

    Geladas were fed or injected with an antigen that contained Burrows' type 2 cholera toxin. Rising agglutinin and vibriocidal titres were observed in the serum, peripheral and mesenteric lymph nodes, spleen and lymphatic tissue of the upper intestine. Oral administration stimulated a more intensive vibriocidal activity in the mesenteric lymphatic nodes and intestinal lymphatic tissue, and within a shorter time than parenteral injection of the same antigen. Immune globulin synthesis paralleled largely the number of immunologically active cells. The agglutinin titres reflected the level of immune globulins and the numbers of globulin producing cells, whereas vibriocidal titres appeared independent of both. In terms of antibody site serum IgG was weight for weight more vibriocidal than serum IgM. PMID:4170509

  5. Effects of atmospheric air plasma treatment of graphite and carbon felt electrodes on the anodic current from Shewanella attached cells.

    PubMed

    Epifanio, Monica; Inguva, Saikumar; Kitching, Michael; Mosnier, Jean-Paul; Marsili, Enrico

    2015-12-01

    The attachment of electrochemically active microorganisms (EAM) on an electrode is determined by both the chemistry and topography of the electrode surface. Pre-treatment of the electrode surface by atmospheric air plasma introduces hydrophilic functional groups, thereby increasing cell attachment and electroactivity in short-term experiments. In this study, we use graphite and carbon felt electrodes to grow the model EAM Shewanella loihica PV-4 at oxidative potential (0.2 V vs. Ag/AgCl). Cell attachment and electroactivity are measured through electrodynamic methods. Atmospheric air plasma pre-treatment increases cell attachment and current output at graphite electrodes by 25%, while it improves the electroactivity of the carbon felt electrodes by 450%. Air plasma pre-treatment decreased the coulombic efficiency on both carbon felt and graphite electrodes by 60% and 80%, respectively. Microbially produced flavins adsorb preferentially at the graphite electrode, and air plasma pre-treatment results in lower flavin adsorption at both graphite and carbon felt electrodes. Results show that air plasma pre-treatment is a feasible option to increase current output in bioelectrochemical systems.

  6. [Tissue and cell interactions in the oral mucosa after cytostatic drugs administration].

    PubMed

    Bykov, V L; Leont'eva, I V

    2011-01-01

    In the preceding work ("Morphology", 2011, issue 2), the regularities of oral mucosal (OM) epithelium injury after the cytostatic drug (CSD) treatment and its further regeneration, were reviewed. This paper presents the systematized summary of current literature data and the authors' own findings on the regularities of CSD effect on non-epithelial OM cell populations and their interactions with each other and the epithelium. The changes of intraepithelial tissue homeostasis, associated with CSD effect on intraepithelial lymphocytes, granulocytes, dendritic antigen presenting cells and melanocytes, interacting with epitheliocytes, are described. The data are presented, indicating that along with the epithelium, the cell populations of lamina propria and submucosal connective tissue, as well as the small blood vessels, are important targets of CSD in the OM tissues. The concept of a unifying model, describing tissue, cellular and molecular mechanisms of the oral mucositis development after CSD treatment, is reviewed.

  7. Intratracheal Administration of Mesenchymal Stem Cells Modulates Tachykinin System, Suppresses Airway Remodeling and Reduces Airway Hyperresponsiveness in an Animal Model

    PubMed Central

    Spaziano, Giuseppe; Piegari, Elena; Matteis, Maria; Cappetta, Donato; Esposito, Grazia; Russo, Rosa; Tartaglione, Gioia; De Palma, Raffaele; Rossi, Francesco; D’Agostino, Bruno

    2016-01-01

    Background The need for new options for chronic lung diseases promotes the research on stem cells for lung repair. Bone marrow-derived mesenchymal stem cells (MSCs) can modulate lung inflammation, but the data on cellular processes involved in early airway remodeling and the potential involvement of neuropeptides are scarce. Objectives To elucidate the mechanisms by which local administration of MSCs interferes with pathophysiological features of airway hyperresponsiveness in an animal model. Methods GFP-tagged mouse MSCs were intratracheally delivered in the ovalbumin mouse model with subsequent functional tests, the analysis of cytokine levels, neuropeptide expression and histological evaluation of MSCs fate and airway pathology. Additionally, MSCs were exposed to pro-inflammatory factors in vitro. Results Functional improvement was observed after MSC administration. Although MSCs did not adopt lung cell phenotypes, cell therapy positively affected airway remodeling reducing the hyperplastic phase of the gain in bronchial smooth muscle mass, decreasing the proliferation of epithelium in which mucus metaplasia was also lowered. Decrease of interleukin-4, interleukin-5, interleukin-13 and increase of interleukin-10 in bronchoalveolar lavage was also observed. Exposed to pro-inflammatory cytokines, MSCs upregulated indoleamine 2,3-dioxygenase. Moreover, asthma-related in vivo upregulation of pro-inflammatory neurokinin 1 and neurokinin 2 receptors was counteracted by MSCs that also determined a partial restoration of VIP, a neuropeptide with anti-inflammatory properties. Conclusion Intratracheally administered MSCs positively modulate airway remodeling, reduce inflammation and improve function, demonstrating their ability to promote tissue homeostasis in the course of experimental allergic asthma. Because of a limited tissue retention, the functional impact of MSCs may be attributed to their immunomodulatory response combined with the interference of neuropeptide

  8. Olive mill wastewater treatment in single-chamber air-cathode microbial fuel cells.

    PubMed

    Bermek, Hakan; Catal, Tunc; Akan, S Süha; Ulutaş, Mehmet Sefa; Kumru, Mert; Özgüven, Mine; Liu, Hong; Özçelik, Beraat; Akarsubaşı, Alper Tunga

    2014-04-01

    Olive mill wastewaters create significant environmental issues in olive-processing countries. One of the most hazardous groups of pollutants in these wastewaters is phenolic compounds. Here, olive mill wastewater was used as substrate and treated in single-chamber air-cathode microbial fuel cells. Olive mill wastewater yielded a maximum voltage of 381 mV on an external resistance of 1 kΩ. Notable decreases in the contents of 3,4-dihydroxybenzoic acid, tyrosol, gallic acid and p-coumaric acid were detected. Chemical oxygen demand removal rates were 65 % while removal of total phenolics by the process was lower (49 %). Microbial community analysis during the olive mill wastewater treating MFC has shown that both exoelectrogenic and phenol-degrading microorganisms have been enriched during the operation. Brevundimonas-, Sphingomonas- and Novosphingobium-related phylotypes were enriched on the anode biofilm, while Alphaproteobacteria and Bacteriodetes dominated the cathode biofilm. As one of the novel studies, it has been demonstrated that recalcitrant olive mill wastewaters could be treated and utilized for power generation in microbial fuel cells.

  9. Flexible inverted polymer solar cells fabricated in air at low temperatures

    NASA Astrophysics Data System (ADS)

    Kuwabara, Takayuki; Wang, Xiaofan; Kusumi, Takuji; Yamaguchi, Takahiro; Taima, Tetsuya; Takahashi, Kohshin

    2016-08-01

    A series of modified indium tin oxide (ITO) materials, including sol-gel zinc-oxide-coated ITO (ITO/ZnO), ZnO nanoparticle-coated ITO (ITO/ZnO-NP), 1,4-bis(3-aminopropyl)piperazine (BAP)-modified ITO, and polyethylenimine ethoxylated (PEIE)-modified ITO, were used for electron-collection electrodes in inverted polymer solar cells (PSCs). The modified ITO electrodes were prepared in air at temperatures below 100 °C, using various ITO films on flexible poly(ethylene terephthalate) substrates (PET-ITO) with sheet resistances ranging from 12 to 60 Ω sq-1. The PET-ITO (12 Ω sq-1)/ZnO-NP PSC exhibited an improved power conversion efficiency (PCE) (2.93%), and this PCE was ˜90% of that observed for a cell using glass-ITO/ZnO-NP (sheet resistance = 10 Ω sq-1 PCE = 3.28%). Additionally, we fabricated a flexible inverted ZnO-NP PSC using an indene-C60 bisadduct (ICBA) as the acceptor material in place of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and obtained a PCE of 4.18%.

  10. Flexible inverted polymer solar cells fabricated in air at low temperatures

    NASA Astrophysics Data System (ADS)

    Kuwabara, Takayuki; Wang, Xiaofan; Kusumi, Takuji; Yamaguchi, Takahiro; Taima, Tetsuya; Takahashi, Kohshin

    2016-08-01

    A series of modified indium tin oxide (ITO) materials, including sol–gel zinc-oxide-coated ITO (ITO/ZnO), ZnO nanoparticle-coated ITO (ITO/ZnO-NP), 1,4-bis(3-aminopropyl)piperazine (BAP)-modified ITO, and polyethylenimine ethoxylated (PEIE)-modified ITO, were used for electron-collection electrodes in inverted polymer solar cells (PSCs). The modified ITO electrodes were prepared in air at temperatures below 100 °C, using various ITO films on flexible poly(ethylene terephthalate) substrates (PET–ITO) with sheet resistances ranging from 12 to 60 Ω sq‑1. The PET–ITO (12 Ω sq‑1)/ZnO-NP PSC exhibited an improved power conversion efficiency (PCE) (2.93%), and this PCE was ∼90% of that observed for a cell using glass–ITO/ZnO-NP (sheet resistance = 10 Ω sq‑1 PCE = 3.28%). Additionally, we fabricated a flexible inverted ZnO-NP PSC using an indene-C60 bisadduct (ICBA) as the acceptor material in place of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and obtained a PCE of 4.18%.

  11. Histopathological Analysis from Gallic Acid Administration on Hippocampal Cell Density, Depression, and Anxiety Related Behaviors in A Trimethyltin Intoxication Model

    PubMed Central

    Moghadas, Marzieh; Edalatmanesh, Mohammad Amin; Robati, Reza

    2016-01-01

    Objective The present study investigated the effects of gallic acid (GA) administration on trimethyltin chloride (TMT) induced anxiety, depression, and hippocampal neurodegen- eration in rats. Materials and Methods In this experimental study, the rats received intraperitoneal (i.p.) injections of TMT (8 mg/kg). The animals received either GA (50, 100 and 150 mg/kg) or saline as the vehicle for 14 consecutive days. We measured depression and anxiety levels of the rats by conducting the behavioral tail suspension (TST), elevatedplusmaze (EPM), and novelty suppressed feeding (NSF) tests. Histological analyses were then used to de- termine the cell densities of different hippocampal subdivisions. The data were analyzed with ANOVA and Tukey’s post hoc test. Results GA administration ameliorated anxiety and depression in the behavioral tests. The cell densities in the CA1, CA2, CA3 and DG hippocampal subdivisionsfrom GA-treat- ed rats were higher than saline treated rats. Conclusion GA treatment against TMT-induced hippocampal degeneration altered cellular loss in the hippocampus and ameliorated the depression-anxiety state in rats. PMID:26862525

  12. Composition of air pollution particles modifies oxidative stress in cells, tissues, and living systems

    EPA Science Inventory

    Epidemiological studies demonstrate an association between increased levels of ambient air pollution particles and human morbidity and mortality. Production of oxidants, either directly by the air pollution particles or by the host response to the particles, appears to be fundame...

  13. Differential effects of acute morphine administrations on polymorphonuclear cell metabolism in various mouse strains.

    PubMed

    Di Francesco, P; Tavazzi, B; Gaziano, R; Lazzarino, G; Casalinuovo, I A; Di Pierro, D; Garaci, E

    1998-01-01

    This paper shows that an acute morphine treatment dose-dependently alters the energetic and oxidative metabolism of polymorphonuclear leukocytes obtained from BALB/c and DBA/2 mice, while phagocytic cells from C57BL/6 were not affected. In sensitive mouse strains, i.e. BALB/c and DBA/2, morphine decreased both ATP concentration and energy charge potential. At the same time, ATP catabolic products, i.e. nucleosides (inosine+adenosine) and oxypurines (hypoxanthine+xanthine+uric acid), significantly increased, indicating an imbalance between energy production and consumption. Morphine treatment also induced malondialdehyde and superoxide anions production in leukocyte cells from sensitive mice. The opiate antagonist naloxone blocked morphine-induced modifications by the lower morphine dose. The same parameters in cells from C57BL/6 mice were not affected. These findings confirm that: i) the phagocytic cells are an important target for the in vivo effects of morphine, and ii) the genotype-dependent variation influences the immunological responsiveness to opiates.

  14. Cycle analysis of an integrated solid oxide fuel cell and recuperative gas turbine with an air reheating system

    NASA Astrophysics Data System (ADS)

    Zhang, Xiongwen; Li, Jun; Li, Guojun; Feng, Zhenping

    Cycle simulation and analysis for two kinds of SOFC/GT hybrid systems were conducted with the help of the simulation tool: Aspen Custom Modeler. Two cycle schemes of recuperative heat exchanger (RHE) and exhaust gas recirculated (EGR) were described according to the air reheating method. The system performance with operating pressure, turbine inlet temperature and fuel cell load were studied based on the simulation results. Then the effects of oxygen utilization, fuel utilization, operating temperature and efficiencies of the gas turbine components on the system performance of the RHE cycle and the EGR cycle were discussed in detail. Simulation results indicated that the system optimum efficiency for the EGR air reheating cycle scheme was higher than that of the RHE cycle system. A higher pressure ratio would be available for the EGR cycle system in comparison with the RHE cycle. It was found that increasing fuel utilization or oxygen utilization would decrease fuel cell efficiency but improve the system efficiency for both of the RHE and EGR cycles. The efficiency of the RHE cycle hybrid system decreased as the fuel cell air inlet temperature increased. However, the system efficiency of EGR cycle increased with fuel cell air inlet temperature. The effect of turbine efficiency on the system efficiency was more obvious than the effect of the compressor and recuperator efficiencies among the gas turbine components. It was also indicated that improving the gas turbine component efficiencies for the RHE cycle increased system efficiency higher than that for the EGR cycle.

  15. IN VITRO EFFECTS OF PARTICULATE MATTER ON AIRWAY EPITHELIAL CELLS ISOLATED FROM CONCENTRATED AIR PARTICLES-EXPOSED SPONTANEOUS HYPERTENSIVE RATS

    EPA Science Inventory

    In vitro effects of particulate matter on airway epithelial cells isolated from concentrated air particles-exposed spontaneous hypertensive rats

    Ines Pagan, Urmila Kodavanti, Paul Evansky, Daniel L Costa and Janice A Dye. U.S. Environmental Protection Agency, ORD, National...

  16. Graphite fiber brush anodes for increased power production in air-cathode microbial fuel cells.

    PubMed

    Logan, Bruce; Cheng, Shaoan; Watson, Valerie; Estadt, Garett

    2007-05-01

    To efficiently generate electricity using bacteria in microbial fuel cells (MFCs), highly conductive noncorrosive materials are needed that have a high specific surface area (surface area per volume) and an open structure to avoid biofouling. Graphite brush anodes, consisting of graphite fibers wound around a conductive, but noncorrosive metal core, were examined for power production in cube (C-MFC) and bottle (B-MFC) air-cathode MFCs. Power production in C-MFCs containing brush electrodes at 9600 m2/m3 reactor volume reached a maximum power density of 2400 mW/m2 (normalized to the cathode projected surface area), or 73 W/m3 based on liquid volume, with a maximum Coulombic efficiency (CE) of 60%. This power density, normalized by cathode projected area, is the highest value yet achieved by an air-cathode system. The increased power resulted from a reduction in internal resistance from 31 to 8 Q. Brush electrodes (4200 m2/m3) were also tested in B-MFCs, consisting of a laboratory media bottle modified to have a single side arm with a cathode clamped to its end. B-MFCs inoculated with wastewater produced up to 1430 mW/m2 (2.3 W/m3, CE = 23%) with brush electrodes, versus 600 mW/m2 with a plain carbon paper electrode. These findings show that brush anodes that have high surface areas and a porous structure can produce high power densities, and therefore have qualities that make them ideal for scaling up MFC systems.

  17. High-Performing Polycarbazole Derivatives for Efficient Solution-Processing of Organic Solar Cells in Air.

    PubMed

    Burgués-Ceballos, Ignasi; Hermerschmidt, Felix; Akkuratov, Alexander V; Susarova, Diana K; Troshin, Pavel A; Choulis, Stelios A

    2015-12-21

    The application of conjugated materials in organic photovoltaics (OPVs) is usually demonstrated in lab-scale spin-coated devices that are processed under controlled inert conditions. Although this is a necessary step to prove high efficiency, testing of promising materials in air should be done in the early stages of research to validate their real potential for low-cost, solution-processed, and large-scale OPVs. Also relevant for approaching commercialization needs is the use of printing techniques that are compatible with upscaling. Here, solution processing of organic solar cells based on three new poly(2,7-carbazole) derivatives is efficiently transferred, without significant losses, to air conditions and to several deposition methods using a simple device architecture. High efficiencies in the range between 5.0 % and 6.3 % are obtained in (rigid) spin-coated, doctor-bladed, and (flexible) slot-die-coated devices, which surpass the reference devices based on poly[N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT). In contrast, inkjet printing does not provide reliable results with the presented polymers, which is attributed to their high molecular weight. When the device area in the best-performing system is increased from 9 mm(2) to 0.7 cm(2), the efficiency drops from 6.2 % to 5.0 %. Photocurrent mapping reveals inhomogeneous current generation derived from changes in the thickness of the active layer. PMID:26663820

  18. Enhanced wound healing by topical administration of mesenchymal stem cells transfected with stromal cell-derived factor-1.

    PubMed

    Nakamura, Yoko; Ishikawa, Hidefumi; Kawai, Katsuya; Tabata, Yasuhiko; Suzuki, Shigehiko

    2013-12-01

    The objective of this study was to investigate the ability of mesenchymal stem cells (MSC) genetically engineered with stromal cell-derived factor-1 (SDF-1) to heal skin wounds. When transfected with SDF-1 plasmid DNA, MSC which were isolated from the bone marrow of rats, secreted SDF-1 for 7 days. In vitro cell migration assay revealed that the SDF-1-engineered MSC (SDF-MSC) enhanced the migration of MSC and dermal fibroblasts to a significantly greater extent than MSC. The SDF-MSC secreted vascular endothelial growth factor, hepatocyte growth factor, and interleukin 6 at a significantly high level. A skin defect model of rats was prepared and MSC and SDF-MSC were applied to the wound to evaluate wound healing in terms of wound size and histological examinations. The wound size decreased significantly faster with SDF-MSC treatment than with MSC and PBS treatments. The length of the neoepithelium and the number of blood vessels newly formed were significantly larger. A cell-tracing experiment with fluorescently labeled cells demonstrated that the percent survival of SDF-MSC in the tissue treated was significantly high compared with that of MSC. It was concluded that SDF-1 genetic engineering is a promising way to promote the wound healing activity of MSC for a skin defect.

  19. Mesenchymal stem cells can prevent alterations in behavior and neurogenesis induced by Aß25-35 administration.

    PubMed

    Hamisha, Keren Nicole; Tfilin, Matanel; Yanai, Joseph; Turgeman, Gadi

    2015-04-01

    Mesenchymal stem cells (MSCs) are known to enhance neurogenesis in the dentate gyrus, as well as to modulate immune cell activity and inflammation. Easily obtained and expanded from the bone marrow and other tissues, MSCs have been proposed as candidates for stem cell therapy in various neurodegenerartive diseases. In the present study, we sought to explore these therapeutic properties of MSC on Aß25-35-induced pathology when coadministered together. Apparently, coadministration of MSC prevented mild cognitive deficits observed following Aß administration alone, by promoting microglial activation and rapid clearance of injected Aß aggregates. Surprisingly, increased hippocampal neurogenesis was observed in the Aß-injected animals and was normal in MSC-coadministered animals just as in control animals. The observed increase in neurogenesis can be explained as a compensating mechanism responsible for the mild and temporary cognitive deficits observed in the Morris water maze assay in Aß-injected animals. Interestingly, MSC engrafted not only to the hippocampus but were also detected in the choroid plexus. We thus conclude that MSC may act in multiple pathways to protect the CNS from Aß pathology, while neurogenesis is a possible compensating mechanism; it is not always activated by MSC, which in turn may interact with local immune cells to regulate Aß accumulation.

  20. Human cord blood cells and myocardial infarction: effect of dose and route of administration on infarct size.

    PubMed

    Henning, Robert J; Burgos, Jose D; Vasko, Mark; Alvarado, Felipe; Sanberg, Cyndy D; Sanberg, Paul R; Morgan, Michael B

    2007-01-01

    There is no consensus regarding the optimal dose of stem cells or the optimal route of administration for the treatment of acute myocardial infarction. Bone marrow cells, containing hematopoietic and mesenchymal stem cells, in doses of 0.5 x 10(6) to >30 x 10(6) have been directly injected into the myocardium or into coronary arteries or infused intravenously in subjects with myocardial infarctions to reduce infarct size and improve heart function. Therefore, we determined the specific effects of different doses of human umbilical cord blood mononuclear cells (HUCBC), which contain hematopoietic and mesenchymal stem cells, on infarct size. In order to determine the optimal technique for stem cell administration, HUCBC were injected directly into the myocardium (IM), or into the LV cavity with the ascending aorta transiently clamped to facilitate coronary artery perfusion (IA), or injected intravenously (IV) in rats 1-2 h after the left anterior coronary artery was permanently ligated. Immune suppressive therapy was not given to any rat. One month later, the infarct size in control rat hearts treated with only Isolyte averaged 23.7 +/- 1.7% of the LV muscle area. Intramyocardial injection of HUCBC reduced the infarct size by 71% with 0.5 x 10(6) HUCBC and by 93% with 4 x 10(6) HUCBC in comparison with the controls (p < 0.001). Intracoronary injection reduced the infarction size by 47% with 0.5 x 10(6) HUCBC and by 80% with 4 x 10(6) HUCBC (p < 0.001), and IV HUCBC reduced infarct size by 51% with 0.5 x 10(6) and by 75-77% with 16-32 million HUCBC (p < 0.001) in comparison with control hearts. With 4 x 10(6) HUCBC, infarction size was 65% smaller with IM HUCBC than with IA HUCBC and 78% smaller than with IV HUCBC (p < 0.05). Nevertheless, IM, IA, and IV HUCBC all produced significant reductions in infarct size in comparison with Isolyte-treated infarcted hearts without requirements for host immune suppression. The present experiments demonstrate that the optimal dose

  1. Administration of a non-NMDA antagonist, GYKI 52466, increases excitotoxic Purkinje cell degeneration caused by ibogaine.

    PubMed

    O'Hearn, E; Molliver, M E

    2004-01-01

    Ibogaine is a tremorigenic hallucinogen that has been proposed for clinical use in treating addiction. We previously reported that ibogaine, administered systemically, produces degeneration of a subset of Purkinje cells in the cerebellum, primarily within the vermis. Ablation of the inferior olive affords protection against ibogaine-induced neurotoxicity leading to the interpretation that ibogaine itself is not directly toxic to Purkinje cells. We postulated that ibogaine produces sustained excitation of inferior olivary neurons that leads to excessive glutamate release at climbing fiber terminals, causing subsequent excitotoxic injury to Purkinje cells. The neuronal degeneration induced by ibogaine provides an animal model for studying excitotoxic injury in order to analyze the contribution of glutamate receptors to this injury and to evaluate neuroprotective strategies. Since non-N-methyl-D-aspartate (NMDA) receptors mediate Purkinje cell excitation by climbing fibers, we hypothesized that 1-4-aminophenyl-methyl-7,8-methylenedioxy-5H-2,3-benzodiazepine (GYKI-52466), which antagonizes non-NMDA receptors, may have a neuroprotective effect by blocking glutamatergic excitation at climbing fiber synapses. To test this hypothesis, rats were administered systemic ibogaine plus GYKI-52466 and the degree of neuronal injury was analyzed in cerebellar sections. The results indicate that the AMPA antagonist GYKI-52466 (10 mg/kg i.p. x 3) does not protect against Purkinje cell injury at the doses used. Rather, co-administration of GYKI-52466 with ibogaine produces increased toxicity evidenced by more extensive Purkinje cell degeneration. Several hypotheses that may underlie this result are discussed. Although the reason for the increased toxicity found in this study is not fully explained, the present results show that a non-NMDA antagonist can produce increased excitotoxic injury under some conditions. Therefore, caution should be exercised before employing glutamate

  2. FLT3 ligand administration after hematopoietic cell transplantation increases circulating dendritic cell precursors that can be activated by CpG oligodeoxynucleotides to enhance T-cell and natural killer cell function.

    PubMed

    Chen, Wei; Chan, Anissa S H; Dawson, Amanda J; Liang, Xueqing; Blazar, Bruce R; Miller, Jeffrey S

    2005-01-01

    Dendritic cells (DCs) are key effectors in innate immunity and play critical roles in triggering adaptive immune responses. FLT3 ligand (FLT3-L) is essential for DC development from hematopoietic progenitors. In a phase I clinical trial, we demonstrated that immunotherapy with subcutaneous injection of FLT3-L is safe and well tolerated in cancer patients recovering from autologous hematopoietic cell transplantation (HCT). FLT3-L administration significantly increased the frequency and absolute number of blood DC precursors without affecting other mature cell lineages during the 6-week course of FLT3-L therapy. After 14 days of FLT3-L administration, the number of blood CD11c + DCs, plasmacytoid DCs (PDCs), and CD14 + monocytes increased by 5.3-, 2.9-, 3.8-fold, respectively, and was maintained at increased levels throughout FLT3-L therapy. FLT3-L-increased blood DCs in HCT patients were immature and had modest enhancing effects on in vitro T-cell proliferation to antigens and natural killer (NK) cell function. The addition of type B CpG oligodeoxynucleotides (ODNs) to peripheral blood mononuclear cells obtained from HCT patients receiving FLT3-L therapy induced rapid maturation of both CD11c + DCs and PDCs and enhanced T-cell proliferative responses. In addition, CpG ODN induced potent activation of NK cells from FLT3-L-treated patients with increased surface CD69 expression and augmented cytotoxicity. CpG ODN-induced activation of NK cells was primarily via an indirect mechanism through PDCs. These findings suggest that FLT3-L mobilization of DC precursors followed by a specific DC stimulus such as CpG ODN may provide a novel strategy to manipulate antitumor immunity in patients after HCT. PMID:15625541

  3. Systemic administration of human adipose-derived stem cells reverts nociceptive hypersensitivity in an experimental model of neuropathy.

    PubMed

    Sacerdote, Paola; Niada, Stefania; Franchi, Silvia; Arrigoni, Elena; Rossi, Alice; Yenagi, Vijay; de Girolamo, Laura; Panerai, Alberto Emilio; Brini, Anna Teresa

    2013-04-15

    Over the last decade, it has been proved that mesenchymal stem cells (MSCs) elicit anti-inflammatory effects. MSCs from adipose tissue (hASCs) differentiate into cells of the mesodermal lineage and transdifferentiate into ectodermal-origin cells. Although there are various etiologies to chronic pain, one common feature is that painful states are associated with increased inflammation. We believe in hASCs as a therapeutic tool also in pathologies involving neuroinflammation and neuronal tissue damage. We have investigated the effect of hASCs injected in a model of neuropathic pain [(mouse sciatic nerve chronic constriction injury (CCI)]. hASCs from 5 donors were characterized, and no major differences were depicted. hASCs were cryopreserved and grown on demand. About 1×10(6), 3×10(6), and 6×10(6) hASCs were intravenously injected into normal immunocompetent mice. No mouse died, and no macroscopic toxicity or behavioral changes were observed, confirming the safety of hASCs. hASCs, intravenously (i.v.) injected into C57BL/6 mice when the neuropathic pain was already established, induced a significant reduction in mechanical allodynia and a complete reversion of thermal hyperalgesia in a dose-response fashion, already 1 day after administration. Moreover, the hASCs effect can be boosted by repeated administrations, allowing a prolonged therapeutic effect. Treatment decreased the level of the CCI-induced proinflammatory cytokine interleukin (IL)-1β and activated the anti-inflammatory cytokine IL-10 in the lesioned nerve. hASCs treatment also restored normal inducible nitric oxide synthase expression in the spinal cord of CCI animals. Our data suggest that hASCs are worthy of further studies as an anti-inflammatory therapy in the treatment of neuropathic pain or chronic inflammatory diseases.

  4. A Genetic Mosaic Analysis With a Repressible Cell Marker Screen to Identify Genes Involved in Tracheal Cell Migration During Drosophila Air Sac Morphogenesis

    PubMed Central

    Chanut-Delalande, Hélène; Jung, Alain C.; Lin, Li; Baer, Magdalena M.; Bilstein, Andreas; Cabernard, Clemens; Leptin, Maria; Affolter, Markus

    2007-01-01

    Branching morphogenesis of the Drosophila tracheal system relies on the fibroblast growth factor receptor (FGFR) signaling pathway. The Drosophila FGF ligand Branchless (Bnl) and the FGFR Breathless (Btl/FGFR) are required for cell migration during the establishment of the interconnected network of tracheal tubes. However, due to an important maternal contribution of members of the FGFR pathway in the oocyte, a thorough genetic dissection of the role of components of the FGFR signaling cascade in tracheal cell migration is impossible in the embryo. To bypass this shortcoming, we studied tracheal cell migration in the dorsal air sac primordium, a structure that forms during late larval development. Using a mosaic analysis with a repressible cell marker (MARCM) clone approach in mosaic animals, combined with an ethyl methanesulfonate (EMS)-mutagenesis screen of the left arm of the second chromosome, we identified novel genes implicated in cell migration. We screened 1123 mutagenized lines and identified 47 lines displaying tracheal cell migration defects in the air sac primordium. Using complementation analyses based on lethality, mutations in 20 of these lines were genetically mapped to specific genomic areas. Three of the mutants were mapped to either the Mhc or the stam complementation groups. Further experiments confirmed that these genes are required for cell migration in the tracheal air sac primordium. PMID:17603108

  5. Adipose-Derived Mesenchymal Stem Cell Administration Does Not Improve Corneal Graft Survival Outcome

    PubMed Central

    Fuentes-Julián, Sherezade; Arnalich-Montiel, Francisco; Jaumandreu, Laia; Leal, Marina; Casado, Alfonso; García-Tuñon, Ignacio; Hernández-Jiménez, Enrique; López-Collazo, Eduardo; De Miguel, Maria P.

    2015-01-01

    The effect of local and systemic injections of mesenchymal stem cells derived from adipose tissue (AD-MSC) into rabbit models of corneal allograft rejection with either normal-risk or high-risk vascularized corneal beds was investigated. The models we present in this study are more similar to human corneal transplants than previously reported murine models. Our aim was to prevent transplant rejection and increase the length of graft survival. In the normal-risk transplant model, in contrast to our expectations, the injection of AD-MSC into the graft junction during surgery resulted in the induction of increased signs of inflammation such as corneal edema with increased thickness, and a higher level of infiltration of leukocytes. This process led to a lower survival of the graft compared with the sham-treated corneal transplants. In the high-risk transplant model, in which immune ocular privilege was undermined by the induction of neovascularization prior to graft surgery, we found the use of systemic rabbit AD-MSCs prior to surgery, during surgery, and at various time points after surgery resulted in a shorter survival of the graft compared with the non-treated corneal grafts. Based on our results, local or systemic treatment with AD-MSCs to prevent corneal rejection in rabbit corneal models at normal or high risk of rejection does not increase survival but rather can increase inflammation and neovascularization and break the innate ocular immune privilege. This result can be partially explained by the immunomarkers, lack of immunosuppressive ability and immunophenotypical secretion molecules characterization of AD-MSC used in this study. Parameters including the risk of rejection, the inflammatory/vascularization environment, the cell source, the time of injection, the immunosuppression, the number of cells, and the mode of delivery must be established before translating the possible benefits of the use of MSCs in corneal transplants to clinical practice. PMID

  6. Toward a lithium-"air" battery: the effect of CO2 on the chemistry of a lithium-oxygen cell.

    PubMed

    Lim, Hyung-Kyu; Lim, Hee-Dae; Park, Kyu-Young; Seo, Dong-Hwa; Gwon, Hyeokjo; Hong, Jihyun; Goddard, William A; Kim, Hyungjun; Kang, Kisuk

    2013-07-01

    Lithium-oxygen chemistry offers the highest energy density for a rechargeable system as a "lithium-air battery". Most studies of lithium-air batteries have focused on demonstrating battery operations in pure oxygen conditions; such a battery should technically be described as a "lithium-dioxygen battery". Consequently, the next step for the lithium-"air" battery is to understand how the reaction chemistry is affected by the constituents of ambient air. Among the components of air, CO2 is of particular interest because of its high solubility in organic solvents and it can react actively with O2(-•), which is the key intermediate species in Li-O2 battery reactions. In this work, we investigated the reaction mechanisms in the Li-O2/CO2 cell under various electrolyte conditions using quantum mechanical simulations combined with experimental verification. Our most important finding is that the subtle balance among various reaction pathways influencing the potential energy surfaces can be modified by the electrolyte solvation effect. Thus, a low dielectric electrolyte tends to primarily form Li2O2, while a high dielectric electrolyte is effective in electrochemically activating CO2, yielding only Li2CO3. Most surprisingly, we further discovered that a high dielectric medium such as DMSO can result in the reversible reaction of Li2CO3 over multiple cycles. We believe that the current mechanistic understanding of the chemistry of CO2 in a Li-air cell and the interplay of CO2 with electrolyte solvation will provide an important guideline for developing Li-air batteries. Furthermore, the possibility for a rechargeable Li-O2/CO2 battery based on Li2CO3 may have merits in enhancing cyclability by minimizing side reactions.

  7. Parietal cell hyperplasia induced by long-term administration of antacids to rats.

    PubMed Central

    Mazzacca, G; Cascione, F; Budillon, G; D'Agostino, L; Cimino, L; Femiano, C

    1978-01-01

    Suspension of magnesium and aluminum hydroxide (30--60 mEq/24h) or a comparable volme of water was orally administered by gastric intubation to two groups of 20 male Wistar rats each over 60 days. The antacid treatment led to a significant increase in the height (0.464 +/- 0.02 mm v. 0.318 +/- 0.06) and in the volume (472 +/- 32 mm3v.328 +/- 45) of the fundic mucosa of the stomach, in the average count of parietal cells per unit area of the mucosa (32.37 +/- 1.8 v. 22.3 +/- 1.6), and in the total parietal cell population of the stomach (53.6 +/- 3.5 x 10(6) v. 43.2 +/- 3.7 x 10(6)). Furthermore fasting serum gastrin concentration was significantly higher in the antacid treated rats (81.2 +/- 7.4 pg/ml) than in control animals (56.9 +/- 6.9 pg/ml). PMID:710969

  8. [Pure red cell aplasia and hypogammaglobulinemia after administration of Dioscorea rhizome and Poria cocos].

    PubMed

    Sato, Takayuki; Ueda, Yasunori

    2015-11-01

    A 56-year-old woman was referred to our department for detailed examination of anemia. She was diagnosed with pure red cell aplasia (PRCA) associated with severe reticulocytopenia based on blood testing and severe erythroblastopenia based on bone marrow aspiration. Blood tests revealed severe hypogammaglobulinemia, but monoclonal protein was not detected in either serum or urine by immunoelectrophoresis. Plasma cells were not increased in bone marrow aspirates or the biopsy specimen. Neither osteolytic lesions nor plasmacytoma was detected by computed tomography. We thus ruled out multiple myeloma. She had been treated with various Chinese herbal medicines prescribed at the referring hospital. We suspected PRCA induced by one of the Chinese herbal medicines and completely discontinued all of these herbal preparations. Hematologic testing revealed that the reticulocyte count and hemoglobin concentration began to recover on day 7 and the hemoglobin concentration and IgG levels had reached reference ranges on day 73 after discontinuation of the Chinese herbal medicines. We suspected Sanyaku (Dioscorea rhizome) or Bukuryou (Poria cocos) to have induced PRCA and hypogammaglobulinemia in this patient. To the best of our knowledge, this is the first report of PRCA and hypogammaglobulinemia induced by a Chinese herbal medicine. Clinicians must consider the possibility of drug-induced PRCA and hypogammaglobulinemia in patients taking Chinese herbal preparations.

  9. Retaining the 3D framework of zinc sponge anodes upon deep discharge in Zn-air cells.

    PubMed

    Parker, Joseph F; Nelson, Eric S; Wattendorf, Matthew D; Chervin, Christopher N; Long, Jeffrey W; Rolison, Debra R

    2014-11-26

    We fabricate three-dimensional zinc electrodes from emulsion-cast sponges of Zn powder that are thermally treated to produce rugged monoliths. This highly conductive, 3D-wired aperiodic scaffold achieves 740 mA h gZn(-1) when discharged in primary Zn-air cells (>90% of theoretical Zn capacity). We use scanning electron microscopy and X-ray diffraction to monitor the microstructural evolution of a series of Zn sponges when oxidized in Zn-air cells to specific depths-of-discharge (20, 40, 60, 80% DOD) at a technologically relevant rate (C/40; 4-6 mA cm(-2)). The Zn sponges maintain their 3D-monolithic form factor at all DOD. The cell resistance remains low under all test conditions, indicating that an inner core of metallic Zn persists that 3D-electrically wires the electrode, even to deep DOD.

  10. Retaining the 3D framework of zinc sponge anodes upon deep discharge in Zn-air cells.

    PubMed

    Parker, Joseph F; Nelson, Eric S; Wattendorf, Matthew D; Chervin, Christopher N; Long, Jeffrey W; Rolison, Debra R

    2014-11-26

    We fabricate three-dimensional zinc electrodes from emulsion-cast sponges of Zn powder that are thermally treated to produce rugged monoliths. This highly conductive, 3D-wired aperiodic scaffold achieves 740 mA h gZn(-1) when discharged in primary Zn-air cells (>90% of theoretical Zn capacity). We use scanning electron microscopy and X-ray diffraction to monitor the microstructural evolution of a series of Zn sponges when oxidized in Zn-air cells to specific depths-of-discharge (20, 40, 60, 80% DOD) at a technologically relevant rate (C/40; 4-6 mA cm(-2)). The Zn sponges maintain their 3D-monolithic form factor at all DOD. The cell resistance remains low under all test conditions, indicating that an inner core of metallic Zn persists that 3D-electrically wires the electrode, even to deep DOD. PMID:25350789

  11. Perspective use of direct human blood as an energy source in air-breathing hybrid microfluidic fuel cells

    NASA Astrophysics Data System (ADS)

    Dector, A.; Escalona-Villalpando, R. A.; Dector, D.; Vallejo-Becerra, V.; Chávez-Ramírez, A. U.; Arriaga, L. G.; Ledesma-García, J.

    2015-08-01

    This work presents a flexible and light air-breathing hybrid microfluidic fuel cell (HμFC) operated under biological conditions. A mixture of glucose oxidase, glutaraldehyde, multi-walled carbon nanotubes and vulcan carbon (GOx/VC-MWCNT-GA) was used as the bioanode. Meanwhile, integrating an air-exposed electrode (Pt/C) as the cathode enabled direct oxygen delivery from air. The microfluidic fuel cell performance was evaluated using glucose obtained from three different sources as the fuel: 5 mM glucose in phosphate buffer, human serum and human blood. For the last fuel, an open circuit voltage and maximum power density of 0.52 V and 0.20 mW cm-2 (at 0.38 V) were obtained respectively; meanwhile the maximum current density was 1.1 mA cm-2. Furthermore, the stability of the device was measured in terms of recovery after several polarization curves, showing excellent results. Although this air-breathing HμFC requires technological improvements before being tested in a biomedical device, it represents the best performance to date for a microfluidic fuel cell using human blood as glucose source.

  12. Systemic and Local Administration of Allogeneic Bone Marrow-Derived Mesenchymal Stem Cells Promotes Fracture Healing in Rats.

    PubMed

    Huang, Shuo; Xu, Liangliang; Zhang, Yifeng; Sun, Yuxin; Li, Gang

    2015-01-01

    Mesenchymal stem cells (MSCs) are immune privileged and a cell source for tissue repair. Previous studies showed that there is systemic mobilization of osteoblastic precursors to the fracture site. We hypothesized that both systemic and local administration of allogeneic MSCs may promote fracture healing. Bone marrow-derived MSCs and skin fibroblasts were isolated from GFP Sprague-Dawley rats, cultured, and characterized. Closed transverse femoral fracture with internal fixation was established in 48 adult male Sprague-Dawley rats, which were randomly assigned into four groups receiving PBS injection, MSC systemic injection, fibroblast systemic injection, and MSC fracture site injection; 2 × 10(6) cells were injected at 4 days after fracture. All animals were sacrificed at 5 weeks after fracture; examinations included weekly radiograph, micro-CT, mechanical testing, histology, immunohistochemistry, and double immunofluorescence. The callus size of MSC injection groups was significantly larger among all the groups. Radiographs and 3D reconstruction images showed that the fracture gaps united in the MSC injected groups, while gaps were still seen in the fibroblast and PBS injection groups. The mechanical properties were significantly higher in the MSC injection groups than those in the fibroblast and PBS groups, but no difference was found between the MSC local and systemic injection groups. Immunohistochemistry and double immunofluorescence demonstrated that GFP-positive MSCs were present in the callus in the MSC injection groups at 5 weeks after fracture, and some differentiated into osteoblasts. Quantitative analysis revealed the number of GFP-positive cells in the callus in the MSC systemic injection group was significantly lower than that of the MSC local injection group. The proportion of GFP osteoblasts in GFP-positive cells in the MSC systemic injection group was significantly lower than that of the MSC local injection group. These findings provide critical

  13. Hydrogeology of the area near the J4 test cell, Arnold Air Force Base, Tennessee

    USGS Publications Warehouse

    Haugh, C.J.

    1996-01-01

    The U.S. Air Force operates a major aerospace systems testing facility at Arnold Engineering Development Center (AEDC) in Coffee County, Tennessee. Dewatering operations at one of the test facilities, the J4 test cell, has affected the local ground-water hydrology. The J4 test cell is approximately 100 feet in diameter, extends approximately 250 feet below land surface, and penetrates several aquifers. Ground water is pumped continuously from around the test cell to keep the cell structurally intact. Because of the test cell's depth, dewatering has depressed water levels in the aquifers surrounding the site. The depressions that have developed exhibit anisotropy that is controlled by zones of high permeability in the aquifers. Additionally, contaminants - predominately volatile organic compounds - are present in the ground-water discharge from the test cell and in ground water at several other Installation Restoration Program (IRP) sites within the AEDC facility. The dewatering activities at J4 are drawing these contaminants from the nearby sites. The effects of dewatering at the J4 test cell were investigated by studying the lithologic and hydraulic characteristics of the aquifers, investigating the anisotropy and zones of secondary permeability using geophysical techniques, mapping the potentiometric surfaces of the underlying aquifers, and developing a conceptual model of the ground-water-flow system local to the test cell. Contour maps of the potentiometric surfaces in the shallow, Manchester, and Fort Payne aquifers (collectively, part of the Highland Rim aquifer system) show anisotropic water-level depressions centered on the J4 test cell. This anisotropy is the result of features of high permeability such as chert-gravel zones in the regolith and fractures, joints, and bedding planes in the bedrock. The presence of these features of high permeability in the Manchester aquifer results in complex flow patterns in the Highland Rim aquifers near the J4 test cell

  14. Optimisation of air cooled, open-cathode fuel cells: Current of lowest resistance and electro-thermal performance mapping

    NASA Astrophysics Data System (ADS)

    Meyer, Quentin; Ronaszegi, Krisztian; Pei-June, Gan; Curnick, Oliver; Ashton, Sean; Reisch, Tobias; Adcock, Paul; Shearing, Paul R.; Brett, Daniel J. L.

    2015-09-01

    Selecting the ideal operating point for a fuel cell depends on the application and consequent trade-off between efficiency, power density and various operating considerations. A systematic methodology for determining the optimal operating point for fuel cells is lacking; there is also the need for a single-value metric to describe and compare fuel cell performance. This work shows how the 'current of lowest resistance' can be accurately measured using electrochemical impedance spectroscopy and used as a useful metric of fuel cell performance. This, along with other measures, is then used to generate an 'electro-thermal performance map' of fuel cell operation. A commercial air-cooled open-cathode fuel cell is used to demonstrate how the approach can be used; in this case leading to the identification of the optimum operating temperature of ∼45 °C.

  15. Perspective: Maintaining surface-phase purity is key to efficient open air fabricated cuprous oxide solar cells

    NASA Astrophysics Data System (ADS)

    Hoye, Robert L. Z.; Brandt, Riley E.; Ievskaya, Yulia; Heffernan, Shane; Musselman, Kevin P.; Buonassisi, Tonio; MacManus-Driscoll, Judith L.

    2015-02-01

    Electrochemically deposited Cu2O solar cells are receiving growing attention owing to a recent doubling in efficiency. This was enabled by the controlled chemical environment used in depositing doped ZnO layers by atomic layer deposition, which is not well suited to large-scale industrial production. While open air fabrication with atmospheric pressure spatial atomic layer deposition overcomes this limitation, we find that this approach is limited by an inability to remove the detrimental CuO layer that forms on the Cu2O surface. Herein, we propose strategies for achieving efficiencies in atmospherically processed cells that are equivalent to the high values achieved in vacuum processed cells.

  16. Ambient salinity modifies the action of triiodothyronine in the air-breathing fish Anabas testudineus Bloch: effects on mitochondria-rich cell distribution, osmotic and metabolic regulations.

    PubMed

    Peter, M C Subhash; Leji, J; Peter, Valsa S

    2011-04-01

    The hydromineral and metabolic actions of thyroid hormone on osmotic acclimation in fish is less understood. We, therefore, studied the short-term action of triiodothyronine (T(3)), the potent thyroid hormone, on the distribution and the function of gill mitochondria-rich (MR) cells and on the whole body hydromineral and metabolic regulations of air-breathing fish (Anabas testudineus) adapted to either freshwater (FW) or acclimated to seawater (SA; 30 g L(-1)). As expected, 24 h T(3) injection (100 ng g(-1)) elevated (P<0.05) plasma T(3) but classically reduced (P<0.05) plasma T(4). The higher Na(+), K(+)-ATPase immunoreactivity and the varied distribution pattern of MR cells in the gills of T(3)-treated FW and SA fish, suggest an action of T(3) on gill MR cell migration, though the density of these cells remained unchanged after T(3) treatment. The ouabain-sensitive Na(+), K(+)-ATPase activity, a measure of hydromineral competence, showed increases (P<0.05) in the gills of both FW and SA fish after T(3) administration, but inhibited (P<0.05) in the kidney of the FW fish and not in the SA fish. Exogenous T(3) reduced glucose (P<0.05) and urea (P<0.05) in the plasma of FW fish, whereas these metabolites were elevated (P<0.05) in the SA fish, suggesting a modulatory effect of ambient salinity on the T(3)-driven metabolic actions. Our data identify gill MR cell as a target for T(3) action as it promotes the spatial distribution and the osmotic function of these cells in both fresh water and in seawater. The results besides confirming the metabolic and osmotic actions of T(3) in fish support the hypothesis that the differential actions of T(3) may be due to the direct influence of ambient salinity, a major environmental determinant that alters the osmotic and metabolic strategies of fish.

  17. VOC and hazardous air pollutant emission factors for military aircraft fuel cell inspection, maintenance, and repair operations

    SciTech Connect

    Nand, K.; Sahu, R.

    1997-12-31

    Accurate emission estimation is one of the key aspects of implementation of any air quality program. The Federal Title 5 program, specially requires an accurate and updated inventory of criteria as well hazardous air pollutants (HAPs) from all facilities. An overestimation of these two categories of pollutants, may cause the facility to be classified as a major source, when in fact it may actually be a minor source, and may also trigger unnecessary compliance requirements. A good example of where overestimation of volatile organic compounds (VOCs) and HAPs is easily possible are military aircraft fuel cells inspection, maintenance, and repair operations. The military aircraft fuel tanks, which are commonly identified as fuel cells, are routinely inspected for maintenance and repairs at military aircraft handling facilities. Prior to entry into the fuel cell by an inspector, fuel cells are first drained into bowsers and then purged with fresh air; the purged air is generally released without any controls to the atmosphere through a stack. The VOC and HAPs emission factors from these operations are not available in the literature for JP-8 fuel, which is being used increasingly by military aircraft. This paper presents two methods for estimating emissions for this source type, which are based on engineering calculations and professional judgment. This paper presents several methods for estimating emissions for this source type, which are based on engineering calculations and professional judgment. There are three emission producing phases during the draining and purging operations: (1) emissions during splash loading of bowsers (unloading of fuel cells), (2) emissions from spillage of fuel during loading of bowsers, and (3) emissions from fuel cell purging operations. Results of the emission estimation, including a comparison of the two emission estimation methods are presented in this paper.

  18. Air-Drying of Cells, the Novel Conditions for Stimulated Synthesis of Triacylglycerol in a Green Alga, Chlorella kessleri

    PubMed Central

    Minoda, Ayumi; Tsuzuki, Mikio; Sato, Norihiro

    2013-01-01

    Triacylglycerol is used for the production of commodities including food oils and biodiesel fuel. Microalgae can accumulate triacylglycerol under adverse environmental conditions such as nitrogen-starvation. This study explored the possibility of air-drying of green algal cells as a novel and simple protocol for enhancement of their triacylglycerol content. Chlorella kessleri cells were fixed on the surface of a glass fibre filter and then subjected to air-drying with light illumination. The dry cell weight, on a filter, increased by 2.7-fold in 96 h, the corresponding chlorophyll content ranging from 1.0 to 1.3-fold the initial one. Concomitantly, the triacylglycerol content remarkably increased to 70.3 mole% of fatty acids and 15.9% (w/w), relative to total fatty acids and dry cell weight, respectively, like in cells starved of nitrogen. Reduction of the stress of air-drying by placing the glass filter on a filter paper soaked in H2O lowered the fatty acid content of triacylglycerol to 26.4 mole% as to total fatty acids. Moreover, replacement of the H2O with culture medium further decreased the fatty acid content of triacylglycerol to 12.2 mole%. It thus seemed that severe dehydration is required for full induction of triacylglycerol synthesis, and that nutritional depletion as well as dehydration are crucial environmental factors. Meanwhile, air-drying of Chlamydomonas reinhardtii cells increased the triacylglycerol content to only 37.9 mole% of fatty acids and 4.8% (w/w), relative to total fatty acids and dry cell weight, respectively, and a marked decrease in the chlorophyll content, on a filter, of 33%. Air-drying thus has an impact on triacylglycerol synthesis in C. reinhardtii also, however, the effect is considerably limited, owing probably to instability of the photosynthetic machinery. This air-drying protocol could be useful for the development of a system for industrial production of triacylglycerol with appropriate selection of the algal species. PMID

  19. Multi-variable mathematical models for the air-cathode microbial fuel cell system

    NASA Astrophysics Data System (ADS)

    Ou, Shiqi; Kashima, Hiroyuki; Aaron, Douglas S.; Regan, John M.; Mench, Matthew M.

    2016-05-01

    This research adopted the version control system into the model construction for the single chamber air-cathode microbial fuel cell (MFC) system, to understand the interrelation of biological, chemical, and electrochemical reactions. The anodic steady state model was used to consider the chemical species diffusion and electric migration influence to the MFC performance. In the cathodic steady state model, the mass transport and reactions in a multi-layer, abiotic cathode and multi-bacteria cathode biofilm were simulated. Transport of hydroxide was assumed for cathodic pH change. This assumption is an alternative to the typical notion of proton consumption during oxygen reduction to explain elevated cathode pH. The cathodic steady state model provided the power density and polarization curve performance results that can be compared to an experimental MFC system. Another aspect considered was the relative contributions of platinum catalyst and microbes on the cathode to the oxygen reduction reaction (ORR). Simulation results showed that the biocatalyst in a cathode that includes a Pt/C catalyst likely plays a minor role in ORR, contributing up to 8% of the total power calculated by the models.

  20. Anolyte recirculation effects in buffered and unbuffered single-chamber air-cathode microbial fuel cells.

    PubMed

    Zhang, Liang; Zhu, Xun; Kashima, Hiroyuki; Li, Jun; Ye, Ding-ding; Liao, Qiang; Regan, John M

    2015-03-01

    Two identical microbial fuel cells (MFCs) with a floating air-cathode were operated under either buffered (MFC-B) or bufferless (MFC-BL) conditions to investigate anolyte recirculation effects on enhancing proton transfer. With an external resistance of 50 Ω and recirculation rate of 1.0 ml/min, MFC-BL had a 27% lower voltage (9.7% lower maximal power density) but a 64% higher Coulombic efficiency (CE) than MFC-B. MFC-B had a decreased voltage output, batch time, and CE with increasing recirculation rate resulting from more oxygen transfer into the anode. However, increasing the recirculation rate within a low range significantly enhanced proton transfer in MFC-BL, resulting in a higher voltage output, a longer batch time, and a higher CE. A further increase in recirculation rate decreased the batch time and CE of MFC-BL due to excess oxygen transfer into anode outweighing the proton-transfer benefits. The unbuffered MFC had an optimal recirculation rate of 0.35 ml/min.

  1. Multi-variable mathematical models for the air-cathode microbial fuel cell system

    DOE PAGES

    Ou, Shiqi; Kashima, Hiroyuki; Aaron, Douglas S.; Regan, John M.; Mench, Matthew M.

    2016-03-10

    This research adopted the version control system into the model construction for the single chamber air-cathode microbial fuel cell (MFC) system, to understand the interrelation of biological, chemical, and electrochemical reactions. The anodic steady state model was used to consider the chemical species diffusion and electric migration influence to the MFC performance. In the cathodic steady state model, the mass transport and reactions in a multi-layer, abiotic cathode and multi-bacteria cathode biofilm were simulated. Transport of hydroxide was assumed for cathodic pH change. This assumption is an alternative to the typical notion of proton consumption during oxygen reduction to explainmore » elevated cathode pH. The cathodic steady state model provided the power density and polarization curve performance results that can be compared to an experimental MFC system. Another aspect we considered was the relative contributions of platinum catalyst and microbes on the cathode to the oxygen reduction reaction (ORR). We found simulation results showed that the biocatalyst in a cathode that includes a Pt/C catalyst likely plays a minor role in ORR, contributing up to 8% of the total power calculated by the models.« less

  2. Visible-light-enhanced electrocatalysis and bioelectrocatalysis coupled in a miniature glucose/air biofuel cell.

    PubMed

    Zhang, Lingling; Xu, Zhikun; Lou, Baohua; Han, Lei; Zhang, Xiaowei; Dong, Shaojun

    2014-09-01

    A glucose/air biofuel cell (BFC) that can convert both chemical and light energy into electricity is described. Polyterthiophene (pTTh), a photoresponsive conducting polymer, serves as cathode and catalyzes the reduction of oxygen. Taking advantage of the good environmental stability and exceptional optical properties of pTTh, the assembled BFC exhibits excellent stability and a fast photoresponse with an open-circuit voltage (V(oc)) of 0.50 V and a maximum power output density (P(max)) of 23.65 μW cm(-2) upon illumination by visible light of 10 mW cm(-2) , which is an enhancement of ca. 22 times as compared to P(max) in the dark. Additionally, we propose a possible mechanism for this enhancement. Fabricating a BFC in this manner provides an energy conversion model that offers high efficiency at low cost, paving an avenue for practical solar energy conversion on a large scale.

  3. Continuous electricity generation by a graphite granule baffled air-cathode microbial fuel cell.

    PubMed

    Feng, Yujie; Lee, He; Wang, Xin; Liu, Yaolan; He, Weihua

    2010-01-01

    A baffled air-cathode microbial fuel cell (BAFMFC) was designed and operated under continuous flow. With glucose fed as substrate, an average voltage of 652 mV was obtained under the external resistance of 1000 Omega (30 degrees C). The maximum power density was 15.2 W/m(3) with the chemical oxygen demand (COD) removal rate of 88.0%. The overall resistance was 13.7 Omega while ohmic internal resistance was 10.8 Omega. Average COD removal rate was 69.7-88.0%, when COD loading varied from 4.11 kg COD/(m(3)NACd) to 16.0 kg COD/(m(3)NACd). The liquid from corn stover steam explosion process (COD=7160+/-50mg/L) was treated by BAFMFC, and the maximum power density was 10.7 W/m(3) with the average COD removal rate was 89.1%. The present study indicated BAFMFC can be comparable to the traditional anaerobic baffled reactor in COD removal rate for high-concentration wastewater and have an advantage in energy harvest from wastewater.

  4. Visible-light-enhanced electrocatalysis and bioelectrocatalysis coupled in a miniature glucose/air biofuel cell.

    PubMed

    Zhang, Lingling; Xu, Zhikun; Lou, Baohua; Han, Lei; Zhang, Xiaowei; Dong, Shaojun

    2014-09-01

    A glucose/air biofuel cell (BFC) that can convert both chemical and light energy into electricity is described. Polyterthiophene (pTTh), a photoresponsive conducting polymer, serves as cathode and catalyzes the reduction of oxygen. Taking advantage of the good environmental stability and exceptional optical properties of pTTh, the assembled BFC exhibits excellent stability and a fast photoresponse with an open-circuit voltage (V(oc)) of 0.50 V and a maximum power output density (P(max)) of 23.65 μW cm(-2) upon illumination by visible light of 10 mW cm(-2) , which is an enhancement of ca. 22 times as compared to P(max) in the dark. Additionally, we propose a possible mechanism for this enhancement. Fabricating a BFC in this manner provides an energy conversion model that offers high efficiency at low cost, paving an avenue for practical solar energy conversion on a large scale. PMID:24961677

  5. Human middle-ear model with compound eardrum and airway branching in mastoid air cells.

    PubMed

    Keefe, Douglas H

    2015-05-01

    An acoustical/mechanical model of normal adult human middle-ear function is described for forward and reverse transmission. The eardrum model included one component bound along the manubrium and another bound by the tympanic cleft. Eardrum components were coupled by a time-delayed impedance. The acoustics of the middle-ear cleft was represented by an acoustical transmission-line model for the tympanic cavity, aditus, antrum, and mastoid air cell system with variable amounts of excess viscothermal loss. Model parameters were fitted to published measurements of energy reflectance (0.25-13 kHz), equivalent input impedance at the eardrum (0.25-11 kHz), temporal-bone pressure in scala vestibuli and scala tympani (0.1-11 kHz), and reverse middle-ear impedance (0.25-8 kHz). Inner-ear fluid motion included cochlear and physiological third-window pathways. The two-component eardrum with time delay helped fit intracochlear pressure responses. A multi-modal representation of the eardrum and high-frequency modeling of the middle-ear cleft helped fit ear-canal responses. Input reactance at the eardrum was small at high frequencies due to multiple modal resonances. The model predicted the middle-ear efficiency between ear canal and cochlea, and the cochlear pressures at threshold.

  6. Development of carbon free diffusion layer for activated carbon air cathode of microbial fuel cells.

    PubMed

    Yang, Wulin; Kim, Kyoung-Yeol; Logan, Bruce E

    2015-12-01

    The fabrication of activated carbon air cathodes for larger-scale microbial fuel cells requires a diffusion layer (DL) that is highly resistant to water leakage, oxygen permeable, and made using inexpensive materials. A hydrophobic polyvinylidene fluoride (PVDF) membrane synthesized using a simple phase inversion process was examined as a low cost ($0.9/m(2)), carbon-free DL that prevented water leakage at high pressure heads compared to a polytetrafluoroethylene/carbon black DL ($11/m(2)). The power density produced with a PVDF (20%, w/v) DL membrane of 1400±7mW/m(2) was similar to that obtained using a wipe DL [cloth coated with poly(dimethylsiloxane)]. Water head tolerance reached 1.9m (∼19kPa) with no mesh supporter, and 2.1m (∼21kPa, maximum testing pressure) with a mesh supporter, compared to 0.2±0.05m for the wipe DL. The elimination of carbon black from the DL greatly simplified the fabrication procedure and further reduced overall cathode costs. PMID:26342345

  7. [Electrode configuration as a factor affecting electricity generation in air-cathode microbial fuel cell].

    PubMed

    You, Shi-Jie; Zhao, Qing-Liang; Jiang, Jun-Qiu

    2006-11-01

    In air-cathode microbial fuel cell (ACMFC), oxygen diffused into the reactor from cathode without PEM can be reduced as electron acceptor via aerobic respiration by facultative microorganisms, resulting in either a decreasing of power generation or electron loss. In this study, ACMFC1 and ACMFC2 with different electrode configuration were compared to examine power density and electron recovery from glucose. The results showed that ACMFC1 generated a maximum power density of 3 070mW/m3 with internal resistance of 302.141 and anode potential of -323mV; while maximum power density of 9 800mW/m3 for ACMFC2 was obtained with internal resistance of 107.79omega and anode potential of -442mV. ACMFC2 could sustain generating electricity for nearly 220 h (ERE of 30.1%), comparing with ACMFC1 of less than 50 h (ERE of 9.78%) under batch operation. Therefore, an improved design for electrode configuration of ACMFC can be performed to generate higher power with low internal resistance, meanwhile, achieve increasing electron recovery simultaneously.

  8. Human middle-ear model with compound eardrum and airway branching in mastoid air cells

    PubMed Central

    Keefe, Douglas H.

    2015-01-01

    An acoustical/mechanical model of normal adult human middle-ear function is described for forward and reverse transmission. The eardrum model included one component bound along the manubrium and another bound by the tympanic cleft. Eardrum components were coupled by a time-delayed impedance. The acoustics of the middle-ear cleft was represented by an acoustical transmission-line model for the tympanic cavity, aditus, antrum, and mastoid air cell system with variable amounts of excess viscothermal loss. Model parameters were fitted to published measurements of energy reflectance (0.25–13 kHz), equivalent input impedance at the eardrum (0.25–11 kHz), temporal-bone pressure in scala vestibuli and scala tympani (0.1–11 kHz), and reverse middle-ear impedance (0.25–8 kHz). Inner-ear fluid motion included cochlear and physiological third-window pathways. The two-component eardrum with time delay helped fit intracochlear pressure responses. A multi-modal representation of the eardrum and high-frequency modeling of the middle-ear cleft helped fit ear-canal responses. Input reactance at the eardrum was small at high frequencies due to multiple modal resonances. The model predicted the middle-ear efficiency between ear canal and cochlea, and the cochlear pressures at threshold. PMID:25994701

  9. Indocyanine green in-situ administration and photothermal destruction of tumor cells using an 808-nm diode laser

    NASA Astrophysics Data System (ADS)

    Chen, Wei R.; Phillips, Claudia S.; Bartels, Kenneth E.; Adams, Robert L.; Nordquist, Robert E.

    1996-05-01

    Laser tumor tissue photothermal interaction was studied using an 808 nm diode laser and indocyanine green as the photosensitizer. This in vitro study employed laser power in the range of 3 to 5 watts and an aqueous ICG solution that was administered to murine mammary tumor tissue by intralesional injection. Histology revealed a highly selective photothermal tumor tissue destruction at the center of the ICG injection, while the tumor cells not in the ICG area were spared. Also studied was the retention of photosensitizer in tissue following different methods of administration. The absorption spectra of tissue in the range of 400 to 900 nm were obtained at different time intervals after ICG injections for liver and kidney tissue, as well as tumor tissue. Our results showed, shortly after intracardiac injection, a rapid increase of ICG concentration in liver and virtually no accumulation of ICG in the subcutaneous tumor tissue. In contrast, the intratumoral-injected ICG remained in the tumor with sufficient concentration for a duration up to 48 hours, particularly in the case of well- circumscribed tumors. The combination of the in situ ICG administration and the 808-nm diode laser provided selective and controllable cancer tissue destruction when appropriate laser powers and dosage of ICG were employed.

  10. Apoptosis and p53 status predict the efficacy of postoperative administration of UFT in non-small cell lung cancer

    PubMed Central

    Tanaka, F; Otake, Y; Yanagihara, K; Yamada, T; Miyahara, R; Kawano, Y; Li, M; Inui, K; Wada, H

    2001-01-01

    To examine whether efficacy of postoperative oral administration of UFT, a 5-fluorouracil derivative chemotherapeutic agent, may be influenced by incidence of apoptosis (apoptosis index) or apoptosis-related gene status (p53 and bcl-2) of the tumour, a total of 162 patients with pathologic stage I non-small cell lung cancer were retrospectively reviewed. UFT was administrated postoperatively to 44 patients (UFT group), and not to the other 118 patients (Control group). For all patients, 5-year survival rate of the UFT group (79.9%) seemed higher than that of the Control group (69.8%), although without significant difference (P = 0.054). For patients with higher apoptotic index, 5-year survival rate of the UFT group (83.3%) was significantly higher than that of the Control group (67.6%, P = 0.039); for patients with lower apoptotic index, however, there was no difference in the prognosis between these two groups. Similarly, UFT was effective for patients without p53 aberrant expression (5-year survival rates: 95.2% for the UFT group and 74.3% for the Control group, P = 0.022), whereas not effective for patients with p53 aberrant expression. Bcl-2 status did not influence the efficacy of UFT. In conclusion, apoptotic index and p53 status are useful factors to predict the efficacy of postoperative adjuvant therapy using UFT. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11161386

  11. Investigation of low temperature solid oxide fuel cells for air-independent UUV applications

    NASA Astrophysics Data System (ADS)

    Moton, Jennie Mariko

    Unmanned underwater vehicles (UUVs) will benefit greatly from high energy density (> 500 Wh/L) power systems utilizing high-energy-density fuels and air-independent oxidizers. Current battery-based systems have limited energy densities (< 400 Wh/L), which motivate development of alternative power systems such as solid oxide fuel cells (SOFCs). SOFC-based power systems have the potential to achieve the required UUV energy densities, and the current study explores how SOFCs based on gadolinia-doped ceria (GDC) electrolytes with operating temperatures of 650°C and lower may operate in the unique environments of a promising UUV power plant. The plant would contain a H 2O2 decomposition reactor to supply humidified O2 to the SOFC cathode and exothermic aluminum/H2O combustor to provide heated humidified H2 fuel to the anode. To characterize low-temperature SOFC performance with these unique O2 and H2 source, SOFC button cells based on nickel/GDC (Gd0.1Ce0.9O 1.95) anodes, GDC electrolytes, and lanthanum strontium cobalt ferrite (La0.6Sr0.4Co0.2Fe0.8O3-δ or LSCF)/GDC cathodes were fabricated and tested for performance and stability with humidity on both the anode and the cathode. Cells were also tested with various reactant concentrations of H2 and O2 to simulate gas depletion down the channel of an SOFC stack. Results showed that anode performance depended primarily on fuel concentration and less on the concentration of the associated increase in product H2O. O 2 depletion with humidified cathode flows also caused significant loss in cell current density at a given voltage. With the humidified flows in either the anode or cathode, stability tests of the button cells at 650 °C showed stable voltage is maintained at low operating current (0.17 A/cm2) at up to 50 % by mole H2O, but at higher current densities (0.34 A/cm2), irreversible voltage degradation occurred at rates of 0.8-3.7 mV/hour depending on exposure time. From these button cell results, estimated average

  12. Interleukin-21 administration leads to enhanced antigen-specific T cell responses and natural killer cells in HIV-1 vaccinated mice.

    PubMed

    Ju, Bin; Li, Dan; Ji, Xiaolin; Liu, Jiandong; Peng, Hong; Wang, Shuo; Liu, Ying; Hao, Yanling; Yee, Cassian; Liang, Hua; Shao, Yiming

    2016-05-01

    Interleukin-21 (IL-21), which belongs to IL-2 γ chain receptor cytokine family, is as an important regulator of immune responses. In this study, we developed a novel strategy for immunizing mice with a DNA/vaccinia/protein vaccine in the presence or absence of mouse IL-21 (mIL-21) to evaluate whether mIL-21 could enhance immune responses. Our results demonstrated that co-immunization with mIL-21 did not increase significantly the capacity of vaccine induced antibodies to bind to HIV-1 GP140. An effect of mIL-21 in adjusting the efficacy of HIV-1 vaccine through enhancing Th1 type immune response was however observed. The frequencies of HIV-1-specific cytokine-producing CD4+ T and CD4+ TEM cells, especially multifunctional T cell responses, were significantly increased by co-administrating with mIL-21. A significant increase was also observed in the frequency of NK cells in mIL-21 adjuvant groups. Taken together, combination of mIL-21 with HIV-1 vaccines led to distinct enhancement of NK cells and T cell immune responses associated with immune protection.

  13. [Injury and reparative regeneration of the oral mucosal epithelium after cytostatic drugs administration (tissue, cell and molecular mechanisms)].

    PubMed

    Bykov, V L; Leont'eva, I V

    2011-01-01

    This paper presents the systematized summary of current literature data and the authors' own findings on the regularities of human and animal surface oral mucosal epithelium (OME) injury caused by cytostatic drugs (CSD) administration, and on the ways of its regeneration after the cytostatic chemotherapy (CSCT) discontinuation. Tissue, cell and molecular mechanisms of CSCT effects on OME, are described. The direct effects of CSD included the epithelial layer attenuation with the derangement of its architecture, epitheliocyte proliferation suppression, apoptosis activation, and differentiation disturbances (involving the broad spectrum of cytological, cytochemical, ultrastructural and molecular-biological changes). In severe cases, these processes resulted in the loss of the epithelial layer integrity with the development of ulceration. Complete epithelial regeneration requires a long period after the CSCT discontinuation. Indirect effects of CSD on OME are associated with the microbial invasion and the diffusion of microbial vital activity products into the epithelium with concurrent leukopenia, immunosuppression and decreased salivary secretion.

  14. Pharmacokinetics of amino acid ester prodrugs of acyclovir after oral administration: interaction with the transporters on Caco-2 cells.

    PubMed

    Katragadda, Suresh; Jain, Ritesh; Kwatra, Deep; Hariharan, Sudharshan; Mitra, Ashim K

    2008-10-01

    In vivo systemic absorption of the amino acid prodrugs of acyclovir (ACV) after oral administration was evaluated in rats. Stability of the prodrugs, L-alanine-ACV (AACV), L-serine-ACV (SACV), L-isoleucine-ACV (IACV), gamma-glutamate-ACV (EACV) and L-valine-ACV (VACV) was evaluated in various tissues. Interaction of these prodrugs with the transporters on Caco-2 cells was studied. In vivo systemic bioavailability of these prodrugs upon oral administration was evaluated in jugular vein cannulated rats. The amino acid ester prodrugs showed affinity towards various amino acid transporters as well as the peptide transporter on the Caco-2 cells. In terms of stability, EACV was most enzymatically stable compared to other prodrugs especially in liver homogenate. In oral absorption studies, ACV and AACV showed high terminal elimination rate constants (lambda(z)). SACV and VACV exhibited approximately five-fold increase in area under the curve (AUC) values relative to ACV (p<0.05). C(max(T)) (maximum concentration) of SACV was observed to be 39+/-22 microM in plasma which is 2 times better than VACV and 15 times better than ACV. C(last(T)) (concentration at the last time point) of SACV was observed to be 0.18+/-0.06 microM in plasma which is two times better than VACV and three times better than ACV. Amino acid ester prodrugs of ACV were absorbed at varying amounts (C(max)) and eliminated at varying rates (lambda(z)) thereby leading to varying extents (AUC). The amino acid ester prodrug SACV owing to its enhanced stability, higher AUC and better concentration at last time point seems to be a promising candidate for the oral treatment of herpes infections.

  15. Enhanced Healing of Diabetic Wounds by Topical Administration of Adipose Tissue-Derived Stromal Cells Overexpressing Stromal-Derived Factor-1: Biodistribution and Engraftment Analysis by Bioluminescent Imaging

    PubMed Central

    Di Rocco, Giuliana; Gentile, Antonietta; Antonini, Annalisa; Ceradini, Francesca; Wu, Joseph C.; Capogrossi, Maurizio C.; Toietta, Gabriele

    2011-01-01

    Chronic ulcers represent a major health problem in diabetic patients resulting in pain and discomfort. Conventional therapy does not guarantee adequate wound repair. In diabetes, impaired healing is partly due to poor endothelial progenitor cells mobilisation and homing, with altered levels of the chemokine stromal-derived factor-1 (SDF-1) at the wound site. Adipose tissue-associated stromal cells (AT-SCs) can provide an accessible source of progenitor cells secreting proangiogenic factors and differentiating into endothelial-like cells. We demonstrated that topical administration of AT-SCs genetically modified ex vivo to overexpress SDF-1, promotes wound healing into diabetic mice. In particular, by in vivo bioluminescent imaging analysis, we monitored biodistribution and survival after transplantation of luciferase-expressing cells. In conclusion, this study indicates the therapeutic potential of AT-SCs administration in wound healing, through cell differentiation, enhanced cellular recruitment at the wound site, and paracrine effects associated with local growth-factors production. PMID:21234108

  16. Enhanced healing of diabetic wounds by topical administration of adipose tissue-derived stromal cells overexpressing stromal-derived factor-1: biodistribution and engraftment analysis by bioluminescent imaging.

    PubMed

    Di Rocco, Giuliana; Gentile, Antonietta; Antonini, Annalisa; Ceradini, Francesca; Wu, Joseph C; Capogrossi, Maurizio C; Toietta, Gabriele

    2010-01-01

    Chronic ulcers represent a major health problem in diabetic patients resulting in pain and discomfort. Conventional therapy does not guarantee adequate wound repair. In diabetes, impaired healing is partly due to poor endothelial progenitor cells mobilisation and homing, with altered levels of the chemokine stromal-derived factor-1 (SDF-1) at the wound site. Adipose tissue-associated stromal cells (AT-SCs) can provide an accessible source of progenitor cells secreting proangiogenic factors and differentiating into endothelial-like cells. We demonstrated that topical administration of AT-SCs genetically modified ex vivo to overexpress SDF-1, promotes wound healing into diabetic mice. In particular, by in vivo bioluminescent imaging analysis, we monitored biodistribution and survival after transplantation of luciferase-expressing cells. In conclusion, this study indicates the therapeutic potential of AT-SCs administration in wound healing, through cell differentiation, enhanced cellular recruitment at the wound site, and paracrine effects associated with local growth-factors production. PMID:21234108

  17. Further study of the intrinsic safety of internally shorted lithium and lithium-ion cells within methane-air

    PubMed Central

    Dubaniewicz, Thomas H.; DuCarme, Joseph P.

    2015-01-01

    National Institute for Occupational Safety and Health (NIOSH) researchers continue to study the potential for lithium and lithium-ion battery thermal runaway from an internal short circuit in equipment for use in underground coal mines. Researchers conducted cell crush tests using a plastic wedge within a 20-L explosion-containment chamber filled with 6.5% CH4-air to simulate the mining hazard. The present work extends earlier findings to include a study of LiFePO4 cells crushed while under charge, prismatic form factor LiCoO2 cells, primary spiral-wound constructed LiMnO2 cells, and crush speed influence on thermal runaway susceptibility. The plastic wedge crush was a more severe test than the flat plate crush with a prismatic format cell. Test results indicate that prismatic Saft MP 174565 LiCoO2 and primary spiral-wound Saft FRIWO M52EX LiMnO2 cells pose a CH4-air ignition hazard from internal short circuit. Under specified test conditions, A123 systems ANR26650M1A LiFePO4 cylindrical cells produced no chamber ignitions while under a charge of up to 5 A. Common spiral-wound cell separators are too thin to meet intrinsic safety standards provisions for distance through solid insulation, suggesting that a hard internal short circuit within these cells should be considered for intrinsic safety evaluation purposes, even as a non-countable fault. Observed flames from a LiMnO2 spiral-wound cell after a chamber ignition within an inert atmosphere indicate a sustained exothermic reaction within the cell. The influence of crush speed on ignitions under specified test conditions was not statistically significant. PMID:26139958

  18. The granule cell density of the dentate gyrus following administration of Urtica dioica extract to young diabetic rats.

    PubMed

    Fazeli, S A; Gharravi, A M; Ghafari, S; Jahanshahi, M; Golalipour, M J

    2008-08-01

    Urtica dioica L. Stinging nettle has long been known worldwide as a medicinal plant. To study the benefits of the nettle in diabetic encephalopathy, the granule cell density of the dentate gyrus of diabetic rats was studied following administration of Urtica dioica extract. A total of 24 male albino Wistar rats were allocated equally to normal, diabetic, preventive and treatment groups. Hyperglycaemia was induced by streptozotocin (80 mg/kg) in the animals of the diabetic and treatment groups. One week after injection of the streptozotocin the animals in the treatment group received a hydroalcoholic extract of Urtica dioica (100 mg/kg/day) for 4 weeks intraperitoneally. The rats of the preventive group received hydroalcoholic extract of U. dioica (100 mg/kg/day) IP for the first 5 days and an injection of streptozotocin (80 mg/kg) on the 6th day. After 5 weeks of study all the rats were sacrificed and coronal sections were taken from the dorsal hippocampal formation of the right cerebral hemispheres and stained with cresyl violet. The area densities of the granule cells were measured and compared in the four groups. The density was lower in the diabetic rats compared with the controls (p > 0.05). The preventive group showed lower cell density than the controls (p > 0.05). The densities in the treated rats were higher than in the diabetic rats (p > 0.05). Furthermore, the control and treated rats showed similar densities (p > 0.05). It seems that U. dioica extract can help compensate for granule cell loss in the diabetic rat dentate gyrus, which can ameliorate cognitive impairment in diabetes. However, preventive use of the extract showed no significant benefit. PMID:18828102

  19. Local administration of cells containing an inserted IL-2 gene and producing IL-2 inhibits growth of human tumours in nu/nu mice.

    PubMed

    Bubenik, J; Voitenok, N N; Kieler, J; Prassolov, V S; Chumakov, P M; Bubenikova, D; Simova, J; Jandlova, T

    1988-12-01

    We have prepared a retroviral expression construct, pPS-IL-2, in which human IL-2 cDNA has been inserted into the polylinker region, and have used the retroviral vector to introduce the functional IL-2 gene into a fibroblast cell line, RAT-1. Peritumoral administration of IL-2-producing RAT-1 cells into congenitally athymic (nu/nu) mice carrying subcutaneous transplants of human carcinoma cells inhibited the growth of the human tumour xenografts.

  20. Numerical investigation of interfacial mass transport resistance and two-phase flow in PEM fuel cell air channels

    NASA Astrophysics Data System (ADS)

    Koz, Mustafa

    Proton exchange membrane fuel cells (PEMFCs) are efficient and environmentally friendly electrochemical engines. The performance of a PEMFC is adversely affected by oxygen (O2) concentration loss from the air flow channel to the cathode catalyst layer (CL). Oxygen transport resistance at the gas diffusion layer (GDL) and air channel interface is a non-negligible component of the O2 concentration loss. Simplified PEMFC performance models in the available literature incorporate the O2 resistance at the GDL-channel interface as an input parameter. However, this parameter has been taken as a constant so far in the available literature and does not reflect variable PEMFC operating conditions and the effect of two-phase flow in the channels. This study numerically calculates the O2 transport resistance at the GDL-air channel interface and expresses this resistance through the non-dimensional Sherwood number (Sh). Local Sh is investigated in an air channel with multiple droplets and films inside. These water features are represented as solid obstructions and only air flow is simulated. Local variations of Sh in the flow direction are obtained as a function of superficial air velocity, water feature size, and uniform spacing between water features. These variations are expressed with mathematical expressions for the PEMFC performance models to utilize and save computational resources. The resulting mathematical correlations for Sh can be utilized in PEMFC performance models. These models can predict cell performance more accurately with the help of the results of this work. Moreover, PEMFC performance models do not need to use a look-up table since the results were expressed through correlations. Performance models can be kept simplified although their predictions will become more realistic. Since two-phase flow in channels is experienced mostly at lower temperatures, performance optimization at low temperatures can be done easier.

  1. Improved red blood cell survival after cardiac operations with administration of urea during cardiopulmonary bypass

    SciTech Connect

    Roberts, D.; Bake, B.; William-Olsson, G.

    1985-01-01

    The plasma hemoglobin and red blood cell survival (half-life of /sup 51/Cr) was studied in 48 patients undergoing single valve replacement or coronary artery bypass graft. Urea or placebo was administered during cardiopulmonary bypass in a prospective, randomized, double-blind manner to test the potential effect on mechanical hemolysis. The mean plasma hemoglobin level at the end of extracorporeal circulation was significantly lower in the urea-treated groups (coronary artery bypass 342 mg/L; valve replacement 364 mg/L) than in the control groups (coronary artery bypass 635 mg/L, valve replacement 518 mg/L. The half-life of /sup 51/Cr was significantly longer in the urea-treated patients (coronary artery bypass 18 days; valve replacement 16 days) than in the control groups (coronary artery bypass 12.4 days; valve replacement 12.7 days) but still below the normal reference value (29 +/- 4 days). The plasma hemoglobin returned to near normal values (50 mg/L) the day after operation (day 1) and remained low with no differences between control and urea-treated groups. The total blood hemoglobin was followed for 2 weeks after operation and showed significantly less anemia in the urea-treated group. The lowest mean blood hemoglobin level was noted between days 5 and 9-114 (coronary artery bypass) and 107 (valve replacement) gm/L in the urea-treated patients compared to 92.3 gm/L in the control subjects. The reduction in the severity of the anemia led to less transfusion in the urea-treated patients (approximately 0.5 unit/patient) than in the control subjects (approximately 1 unit/patient) between days 3 and 14.

  2. Biphasic bisperoxovanadium administration and Schwann cell transplantation for repair after cervical contusive spinal cord injury

    PubMed Central

    Walker, Chandler L.; Wang, Xiaofei; Bullis, Carli; Liu, Nai-Kui; Lu, Qingbo; Fry, Colin; Deng, Lingxiao; Xu, Xiao-Ming

    2014-01-01

    Schwann cells (SCs) hold promise for spinal cord injury (SCI) repair; however, there are limitations for use as a lone treatment. We showed acute inhibition of the phosphatase and tensin homologue (PTEN) by bisperoxovanadium (bpV) was neuroprotective and enhanced function following cervical hemicontusion SCI. We hypothesized that combining acute bpV therapy and delayed SC engraftment would further improve neuroprotection and recovery after cervical SCI. Adult female Sprague Dawley (SD) rats were randomly sorted into 5 groups: sham, vehicle, bpV, SC transplantation, and bpV + SC transplantation. SCs were isolated from adult green fluorescent protein (GFP)-expressing SD rats (GFP-SCs). 200 g/kg bpV(pic) was administered intraperitoneally (i.p.) twice daily for 7 days post-SCI in bpV-treated groups. GFP-SCs (1 × 106 in 5 μl medium) were transplanted into the lesion epicenter at the 8th day post-SCI. Forelimb function was tested for 10 weeks and histology was assessed. bpV alone significantly reduced lesion (by 40%, p<0.05) and cavitation (by 65%, p<0.05) and improved functional recovery (p <0.05) compared to injury alone. The combination promoted similar neuroprotection (p<0.01 vs. injury); however, GFP-SCs alone did not. Both SC-transplanted groups exhibited remarkable long-term SC survival, SMI-31+ axon ingrowth and RECA-1+ vasculature presence in the SC graft; however, bpV + SCs promoted an 89% greater axon-to-lesion ratio than SCs only. We concluded that bpV likely contributed largely to the neuroprotective and functional benefits while SCs facilitated considerable host-tissue interaction and modification. The combination of the two shows promise as an attractive strategy to enhance recovery after SCI. PMID:25510318

  3. Relationship between Air Traffic Selection and Training (AT-SAT)) Battery Test Scores and Composite Scores in the Initial en Route Air Traffic Control Qualification Training Course at the Federal Aviation Administration (FAA) Academy

    ERIC Educational Resources Information Center

    Kelley, Ronald Scott

    2012-01-01

    Scope and Method of Study: This study focused on the development and use of the AT-SAT test battery and the Initial En Route Qualification training course for the selection, training, and evaluation of air traffic controller candidates. The Pearson product moment correlation coefficient was used to measure the linear relationship between the…

  4. Air traffic coverage

    SciTech Connect

    George, L.L.

    1988-09-16

    The Federal Aviation Administration plans to consolidate several hundred air traffic control centers and TRACONs into area control facilities while maintaining air traffic coverage. This paper defines air traffic coverage, a performance measure of the air traffic control system. Air traffic coverage measures performance without controversy regarding delay and collision probabilities and costs. Coverage measures help evaluate alternative facility architectures and help schedule consolidation. Coverage measures also help evaluate protocols for handling one facility's air traffic to another facility in case of facility failure. Coverage measures help evaluate radar, communications and other air traffic control systems and procedures. 4 refs., 2 figs.,

  5. [Administration of bone marrow mesenchymal stem cells attenuates inflammation of rats with sepsis].

    PubMed

    Hao, Yufang; Geng, Lixia

    2016-09-01

    Objective To investigate the therapeutic effects of bone marrow-derived mesenchymal stem cells (BMSCs) in rats with sepsis. Methods Forty-eight Wistar rats were divided into blank group, sham group, model group and treatment group. Sepsis model was made using cecum ligation and puncture (CLP). BMSCs were extracted and cultured to the third generation. The rats in the treatment group received BMSCs through a tail vein and the rats in the model group received an equivalent dose of PBS. The survival rate was recorded in each group 72 hours after operation. Pathological changes of lung tissues were observed by HE staining. The mRNA levels of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), fork head box protein 3 (Foxp3), CC chemokine ligand 2 (CCL2) were tested by quantitative real-time fluorescence PCR. The serum levels of IL-6, IL-17 and TNF-α proteins were detected by ELISA. Results In both blank group and sham group, the survival rate and histological changes of the lungs showed normal; no bacteria were found growing in rats' blood culture; IL-6, IL-17, TNF-α, CCL2, Foxp3 mRNA and IL-6, IL-17, TNF-α protein levels had no significant differences. In the model group, the survival rate of rats was obviously lower than that of the sham group; the pathological changes of the lungs were significant; any amount of enterobacteria were seen growing in rats' blood culture; IL-6, IL-17, TNF-α, CCL2 mRNA and protein expression levels were apparently higher than those of sham group, while Foxp3 mRNA expression level was obviously lower than that of sham group. In the treatment group, the survival rate was significantly higher than that of the model group; the pathological changes of the lung tissues were evidently eased; IL-6, IL-17, TNF-α, CCL2 mRNA and protein expression levels significantly decreased compared with the model group, while Foxp3 mRNA expression level significantly increased compared with the model group. Conclusion BMSCs injection increases the

  6. Photo-degradation in air of the active layer components in a thiophene-quinoxaline copolymer:fullerene solar cell.

    PubMed

    Hansson, Rickard; Lindqvist, Camilla; Ericsson, Leif K E; Opitz, Andreas; Wang, Ergang; Moons, Ellen

    2016-04-28

    We have studied the photo-degradation in air of a blend of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1), and how the photo-degradation affects the solar cell performance. Using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, changes to the electronic structure of TQ1 and PCBM caused by illumination in ambient air are investigated and compared between the pristine materials and the blend. The NEXAFS spectra show that the unoccupied molecular orbitals of TQ1 are not significantly changed by the exposure of pristine TQ1 to light in air, whereas those of PCBM are severely affected as a result of photo-induced degradation of PCBM. Furthermore, the photo-degradation of PCBM is accelerated by blending it with TQ1. While the NEXAFS spectrum of TQ1 remains unchanged upon illumination in air, its valence band spectrum shows that the occupied molecular orbitals are weakly affected. Yet, UV-Vis absorption spectra demonstrate photo-bleaching of TQ1, which is attenuated in the presence of PCBM in blend films. Illumination of the active layer of TQ1:PCBM solar cells prior to cathode deposition causes severe losses in electrical performance. PMID:27051887

  7. Photo-degradation in air of the active layer components in a thiophene-quinoxaline copolymer:fullerene solar cell.

    PubMed

    Hansson, Rickard; Lindqvist, Camilla; Ericsson, Leif K E; Opitz, Andreas; Wang, Ergang; Moons, Ellen

    2016-04-28

    We have studied the photo-degradation in air of a blend of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1), and how the photo-degradation affects the solar cell performance. Using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, changes to the electronic structure of TQ1 and PCBM caused by illumination in ambient air are investigated and compared between the pristine materials and the blend. The NEXAFS spectra show that the unoccupied molecular orbitals of TQ1 are not significantly changed by the exposure of pristine TQ1 to light in air, whereas those of PCBM are severely affected as a result of photo-induced degradation of PCBM. Furthermore, the photo-degradation of PCBM is accelerated by blending it with TQ1. While the NEXAFS spectrum of TQ1 remains unchanged upon illumination in air, its valence band spectrum shows that the occupied molecular orbitals are weakly affected. Yet, UV-Vis absorption spectra demonstrate photo-bleaching of TQ1, which is attenuated in the presence of PCBM in blend films. Illumination of the active layer of TQ1:PCBM solar cells prior to cathode deposition causes severe losses in electrical performance.

  8. Enhanced performance of an air-cathode microbial fuel cell with oxygen supply from an externally connected algal bioreactor.

    PubMed

    Kakarla, Ramesh; Kim, Jung Rae; Jeon, Byong-Hun; Min, Booki

    2015-11-01

    An algae bioreactor (ABR) was externally connected to air-cathode microbial fuel cells (MFCs) to increase power generation by supplying a high amount of oxygen to cathode electrode. The MFC with oxygen fed from ABR produced maximum cell voltage and cathode potential at a fixed loading of 459 mV and 10 mV, respectively. During polarization analysis, the MFC displayed a maximum power density of 0.63 W/m(2) (at 2.06 A/m(2)) using 39.2% O2 from ABR, which was approximately 30% higher compared with use of atmospheric air (0.44 W/m(2), 20.8% O2,). The cyclic voltammogram analysis exhibited a higher reduction current of -137 mA with 46.5% O2 compared to atmospheric air (-115 mA). Oxygen supply by algae bioreactor to air-cathode MFC could also maintain better MFC performance in long term operation by minimizing cathode potential drop over time.

  9. The impacts of replacing air bubbles with microspheres for the clarification of algae from low cell-density culture.

    PubMed

    Ometto, Francesco; Pozza, Carlo; Whitton, Rachel; Smyth, Beatrice; Gonzalez Torres, Andrea; Henderson, Rita K; Jarvis, Peter; Jefferson, Bruce; Villa, Raffaella

    2014-04-15

    Dissolved Air Flotation (DAF) is a well-known coagulation-flotation system applied at large scale for microalgae harvesting. Compared to conventional harvesting technologies DAF allows high cell recovery at lower energy demand. By replacing microbubbles with microspheres, the innovative Ballasted Dissolved Air Flotation (BDAF) technique has been reported to achieve the same algae cell removal efficiency, while saving up to 80% of the energy required for the conventional DAF unit. Using three different algae cultures (Scenedesmus obliquus, Chlorella vulgaris and Arthrospira maxima), the present work investigated the practical, economic and environmental advantages of the BDAF system compared to the DAF system. 99% cells separation was achieved with both systems, nevertheless, the BDAF technology allowed up to 95% coagulant reduction depending on the algae species and the pH conditions adopted. In terms of floc structure and strength, the inclusion of microspheres in the algae floc generated a looser aggregate, showing a more compact structure within single cell alga, than large and filamentous cells. Overall, BDAF appeared to be a more reliable and sustainable harvesting system than DAF, as it allowed equal cells recovery reducing energy inputs, coagulant demand and carbon emissions.

  10. Electronic modification of Pt via Ti and Se as tolerant cathodes in air-breathing methanol microfluidic fuel cells.

    PubMed

    Ma, Jiwei; Habrioux, Aurélien; Morais, Cláudia; Alonso-Vante, Nicolas

    2014-07-21

    We reported herein on the use of tolerant cathode catalysts such as carbon supported Pt(x)Ti(y) and/or Pt(x)Se(y) nanomaterials in an air-breathing methanol microfluidic fuel cell. In order to show the improvement of mixed-reactant fuel cell (MRFC) performances obtained with the developed tolerant catalysts, a classical Pt/C nanomaterial was used for comparison. Using 5 M methanol concentration in a situation where the fuel crossover is 100% (MRFC-mixed reactant fuel cell application), the maximum power density of the fuel cell with a Pt/C cathodic catalyst decreased by 80% in comparison with what is observed in the laminar flow fuel cell (LFFC) configuration. With Pt(x)Ti(y)/C and Pt(x)Se(y)/C cathode nanomaterials, the performance loss was only 55% and 20%, respectively. The evaluation of the tolerant cathode catalysts in an air-breathing microfluidic fuel cell suggests the development of a novel nanometric system that will not be size restricted. These interesting results are the consequence of the high methanol tolerance of these advanced electrocatalysts via surface electronic modification of Pt. Herein we used X-ray photoelectron and in situ FTIR spectroscopies to investigate the origin of the high methanol tolerance on modified Pt catalysts.

  11. Safety Evaluation of Dry Powder Formulations by Direct Dispersion onto Air-Liquid Interface Cultured Cell Layer.

    PubMed

    Asai, Ayumu; Okuda, Tomoyuki; Yamauchi, Tomoyo; Sugiura, Yuka; Okamoto, Hirokazu

    2016-01-01

    Most safety evaluations of dry powder inhalers (DPIs) using cultured cells have been performed with dry powder formulations dissolved in a medium. However, this method is not considered to be suitable to evaluate the safety of inhaled dry powder formulations correctly since it cannot reflect the actual phenomenon on the respiratory epithelial surface. In this study, we established a novel in-vitro safety evaluation system suitable for DPIs by combining an air-liquid interface cultured cell layer and a device for dispersing dry powders, and evaluated the safety of candidate excipients of dry powders for inhalation. The safety of excipients (sugars, amino acids, cyclodextrins, and positive controls) in solutions was compared using submerged cell culture systems with a conventional 96-well plate and Transwell(®). The sensitivity of the cells grown in Transwell(®) was lower than that of those grown in the 96-well plate. Dry powders were prepared by spray-drying and we evaluated their safety with a novel in-vitro safety evaluation system using an air-liquid interface cultured cell layer. Dry powders decreased the cell viability with doses more than solutions. On the other hand, dissolving the dry powders attenuated their cytotoxicity. This suggested that the novel in-vitro safety evaluation system would be suitable to evaluate the safety of DPIs with high sensitivity.

  12. MRI measurement of angiogenesis and the therapeutic effect of acute marrow stromal cell administration on traumatic brain injury.

    PubMed

    Li, Lian; Chopp, Michael; Ding, Guang Liang; Qu, Chang Sheng; Li, Qing Jiang; Lu, Mei; Wang, Shiyang; Nejad-Davarani, Siamak P; Mahmood, Asim; Jiang, Quan

    2012-11-01

    Using magnetic resonance imaging (MRI), the present study was undertaken to investigate the therapeutic effect of acute administration of human bone marrow stromal cells (hMSCs) on traumatic brain injury (TBI) and to measure the temporal profile of angiogenesis after the injury with or without cell intervention. Male Wistar rats (300 to 350 g, n=18) subjected to controlled cortical impact TBI were intravenously injected with 1 mL of saline (n=9) or hMSCs in suspension (n=9, 3 × 10(6) hMSCs) 6 hours after TBI. In-vivo MRI acquisitions of T2-weighted imaging, cerebral blood flow (CBF), three-dimensional (3D) gradient echo imaging, and blood-to-brain transfer constant (Ki) of contrast agent were performed on all animals 2 days after injury and weekly for 6 weeks. Sensorimotor function and spatial learning were evaluated. Volumetric changes in the trauma-induced brain lesion and the lateral ventricles were tracked and quantified using T2 maps, and hemodynamic alteration and blood-brain barrier permeability were monitored by CBF and Ki, respectively. Our data show that transplantation of hMSCs 6 hours after TBI leads to reduced cerebral atrophy, early and enhanced cerebral tissue perfusion and improved functional outcome compared with controls. The hMSC treatment increases angiogenesis in the injured brain, which may promote neurologic recovery after TBI.

  13. Caffeine administration prevents retinal neuroinflammation and loss of retinal ganglion cells in an animal model of glaucoma

    PubMed Central

    Madeira, Maria H.; Ortin-Martinez, Arturo; Nadal-Nícolas, Francisco; Ambrósio, António F.; Vidal-Sanz, Manuel; Agudo-Barriuso, Marta; Santiago, Ana Raquel

    2016-01-01

    Glaucoma is the second leading cause of blindness worldwide, being characterized by progressive optic nerve damage and loss of retinal ganglion cells (RGCs), accompanied by increased inflammatory response involving retinal microglial cells. The etiology of glaucoma is still unknown, and despite elevated intraocular pressure (IOP) being a major risk factor, the exact mechanisms responsible for RGC degeneration remain unknown. Caffeine, which is an antagonist of adenosine receptors, is the most widely consumed psychoactive drug in the world. Several evidences suggest that caffeine can attenuate the neuroinflammatory responses and afford protection upon central nervous system (CNS) injury. We took advantage of a well characterized animal model of glaucoma to investigate whether caffeine administration controls neuroinflammation and elicits neuroprotection. Caffeine or water were administered ad libitum and ocular hypertension (OHT) was induced by laser photocoagulation of the limbal veins in Sprague Dawley rats. Herein, we show that caffeine is able to partially decrease the IOP in ocular hypertensive animals. More importantly, we found that drinking caffeine prevented retinal microglia-mediated neuroinflammatory response and attenuated the loss of RGCs in animals with ocular hypertension (OHT). This study opens the possibility that caffeine or adenosine receptor antagonists might be a therapeutic option to manage RGC loss in glaucoma. PMID:27270337

  14. The tumor protection effect of high-frequency administration of whole tumor cell vaccine and enhanced efficacy by the protein component from Agrocybe aegerita

    PubMed Central

    Liang, Yi; Sun, Hui

    2015-01-01

    Whole tumor cell vaccines have been widely studied and elicits limited immune responses because of the poor immunogenicity. In the present study, we discovered that high-frequency administration of irradiated whole tumor cell vaccine triggered rejection of tumor cells (90% or 100% of the mice that were vaccinated with irradiated H22 cells or S180 respectively were protected), and provided cross-protection and long-term anti-tumor immunity in BALB/c mouse models. The antitumor activity required CD4+, CD8+ T cells and macrophage that was proved in the nude mice and cell depletion mouse models. The adoptive transfer experiment suggested that repeated whole tumor cell vaccination successfully stimulated the anti-tumor response by activation of the immune cells. A high immunization frequency within a short period of time and the presence of glycosylated molecules and nucleic acids on the surface of intact tumor cells were crucial for the successful prevention of tumor growth by whole tumor cell vaccines. Moreover, Yt, the protein component from fungus Agrocybe aegerita, increased whole tumor cell vaccine-mediated tumor rejection and cross-protection effect. These data indicated that the frequency of administration of whole tumor cell vaccines was of critical importance for the efficacy, which needed to be integrated into vaccine strategies for producing potential vaccines. PMID:26221228

  15. Optical emission spectroscopy characterizations of micro-air plasma used for simulation of cell membrane poration

    NASA Astrophysics Data System (ADS)

    Zerrouki, A.; Motomura, H.; Ikeda, Y.; Jinno, M.; Yousfi, M.

    2016-07-01

    A micro-air corona discharge, which is one of the plasmas successfully used for gene transfection in terms of high transfection and cell viability rates, is characterized by optical emission spectroscopy. This non-equilibrium low temperature plasma is generated from the tip of a pulsed high voltage micro-tube (0.2 mm inner diameter and 0.7 mm for outer diameter) placed 2 mm in front of a petri dish containing deionized water and set on a grounded copper plate. The electron temperature, equal to about 6.75 eV near the electrode tip and decreased down to 3.4 eV near the plate, has been estimated, with an error bar of about 30%, from an interesting approach based on the experimental ratio of the closest nitrogen emission spectra of \\text{N}2+ (FNS) at 391.4 nm and N2(SPS) at 394.3 nm. This is based on one hand on a balance equation between creations and losses of the excited upper levels of these two UV spectra and on the other hand on the electron impact rates of the creation of these upper levels calculated from solution of the multi-term Boltzmann equation. Then using the measured Hα spectrum, electron density n e has been estimated from Stark broadening versus the inter-electrode position with an average error bar of about 50%. n e  ≈  1  ×  1015 cm-3 is near the tip coherent with the usual magnitude of electron density in the streamer head developed near the tip of the corona discharges. Rotational temperatures, estimated from comparison of synthetic and experimental spectra of OH(A  -  X), \\text{N}2+ (FNS) at 391.4 nm, and N2(SPS) at 337 nm are respectively equal to 2350 K, 2000 K and 700 K in the gap space. This clearly underlines a thermal non-equilibrium of the corresponding excited species generated inside the thin streamer filaments. But, due to the high dilution of these species in the background gas, these high rotational temperatures do not affect the mean gas temperature that remains close to 300

  16. Optical emission spectroscopy characterizations of micro-air plasma used for simulation of cell membrane poration

    NASA Astrophysics Data System (ADS)

    Zerrouki, A.; Motomura, H.; Ikeda, Y.; Jinno, M.; Yousfi, M.

    2016-07-01

    A micro-air corona discharge, which is one of the plasmas successfully used for gene transfection in terms of high transfection and cell viability rates, is characterized by optical emission spectroscopy. This non-equilibrium low temperature plasma is generated from the tip of a pulsed high voltage micro-tube (0.2 mm inner diameter and 0.7 mm for outer diameter) placed 2 mm in front of a petri dish containing deionized water and set on a grounded copper plate. The electron temperature, equal to about 6.75 eV near the electrode tip and decreased down to 3.4 eV near the plate, has been estimated, with an error bar of about 30%, from an interesting approach based on the experimental ratio of the closest nitrogen emission spectra of \\text{N}2+ (FNS) at 391.4 nm and N2(SPS) at 394.3 nm. This is based on one hand on a balance equation between creations and losses of the excited upper levels of these two UV spectra and on the other hand on the electron impact rates of the creation of these upper levels calculated from solution of the multi-term Boltzmann equation. Then using the measured Hα spectrum, electron density n e has been estimated from Stark broadening versus the inter-electrode position with an average error bar of about 50%. n e  ≈  1  ×  1015 cm‑3 is near the tip coherent with the usual magnitude of electron density in the streamer head developed near the tip of the corona discharges. Rotational temperatures, estimated from comparison of synthetic and experimental spectra of OH(A  ‑  X), \\text{N}2+ (FNS) at 391.4 nm, and N2(SPS) at 337 nm are respectively equal to 2350 K, 2000 K and 700 K in the gap space. This clearly underlines a thermal non-equilibrium of the corresponding excited species generated inside the thin streamer filaments. But, due to the high dilution of these species in the background gas, these high rotational temperatures do not affect the mean gas temperature that remains close to 300

  17. Mechanisms of corticosteroid action on lymphocyte subpopulations. III. Differential effects of dexamethasone administration on subpopulations of effector cells mediating cellular cytotoxicity in man

    PubMed Central

    Parrillo, J. E.; Fauci, A. S.

    1978-01-01

    The present study investigated the effect of dexamethasone (DEX) administration on different populations of mononuclear cells and neutrophils mediating antibody-dependent cellular cytotoxicity (ADCC) against different target cells. Mononuclear cells (lymphocytes and monocytes) and neutrophils were obtained from twenty-seven normal volunteers at 0, 4, 24 and 48 hr after oral administration of 21 mg of DEX. ADCC was determined utilizing the following targets: human red blood cells (HRBC), Chang liver cells (Ch) and human heart cells (HHC). The predominant mononuclear effector in HRBC killing was shown to be a monocyte and in Ch and HHC killing, a K cell. As previously shown, DEX produced a profound monocytopenia and lymphocytopenia at 4 hr with a return of lymphocyte counts to normal and monocyte counts to supra-normal at 24 hr. At the point of maximal monocytopenia, monocyte-mediated HRBC killing decreased from a geometric mean of 14 to 4 lytic units per 108 effector cells (P<0·05) and rebounded at 24 hr to a mean of 39 lytic units (P<0·02) with the rebound monocytosis. At the point of absolute lymphopenia (4 hr), there was a relative enrichment in the proportion of lymphocytes bearing an Fc receptor (K cells, P<0·01). Concomitant with this was an increase in ADCC against Ch and HHC from geometric means of 1121 to 7172 lytic units and 939 to 7354 lytic units (P<0·001) respectively. Thus, a major action of DEX administration on mononuclear ADCC was to differentially enrich or deplete different effector cells to and from the circulation, causing changes in cytotoxicity. Since the cytotoxicity paralleled the proportion of effector cells, the cells remaining in the circulation following DEX administration retained normal antibody-dependent cytotoxic capabilities. Neutrophil-mediated ADCC against HRBC significantly increased at 4 hr from a geometric mean of 3785 to 20142 lytic units (P<0·02) concomitant with the blood neutrophilia and remained elevated for 72 hr

  18. Aire-dependent thymic expression of desmoglein 3, the autoantigen in pemphigus vulgaris, and its role in T-cell tolerance.

    PubMed

    Wada, Naoko; Nishifuji, Koji; Yamada, Taketo; Kudoh, Jun; Shimizu, Nobuyoshi; Matsumoto, Mitsuru; Peltonen, Leena; Nagafuchi, Seiho; Amagai, Masayuki

    2011-02-01

    In the mechanism of thymus-induced central tolerance, the transcription factor Aire has been demonstrated to promote the expression of a wide range of peripheral organ-specific antigens (Ags) in the medullary thymic epithelial cells (mTECs), which serve as self-Ags in negative selection. We examined the expression of desmoglein 3 (Dsg3), the autoantigen in pemphigus vulgaris (PV), in mouse thymus and the involvement of Aire in tolerance to Dsg3. Immunofluorescence and in situ hybridization revealed Dsg3 in single cells or in clusters in ∼3% of mTECs near the cortico-medullary junction of the thymus in C57BL/6 mice. Dsg3-expressing mTECs also expressed some Ags of skin-unrelated peripheral organs simultaneously. In contrast, Dsg3-positive mTECs were not detected in the Aire(-/-) thymus. Adoptive transfer of splenocytes from Aire(-/-) mice immunized with Dsg3 did not induce anti-Dsg3 IgG production or PV phenotype in Rag2(-/-) recipient mice. However, Aire(-/-) CD4(+) T cells, but not Aire(+/+) CD4(+) T cells, induced low levels of anti-Dsg3 IgG production when transferred with Dsg3(-/-) B cells. These findings indicate that Aire has an important role in Dsg3 expression as well as in selection of T cells that help B cells to produce anti-Dsg3 IgG in thymus.

  19. Prevention and treatment of colon cancer by peroral administration of HAMLET (human α-lactalbumin made lethal to tumour cells)

    PubMed Central

    Puthia, Manoj; Storm, Petter; Nadeem, Aftab; Hsiung, Sabrina; Svanborg, Catharina

    2014-01-01

    Background Most colon cancers start with dysregulated Wnt/β-catenin signalling and remain a major therapeutic challenge. Examining whether HAMLET (human α-lactalbumin made lethal to tumour cells) may be used for colon cancer treatment is logical, based on the properties of the complex and its biological context. Objective To investigate if HAMLET can be used for colon cancer treatment and prevention. ApcMin/+ mice, which carry mutations relevant to hereditary and sporadic human colorectal tumours, were used as a model for human disease. Method HAMLET was given perorally in therapeutic and prophylactic regimens. Tumour burden and animal survival of HAMLET-treated and sham-fed mice were compared. Tissue analysis focused on Wnt/β-catenin signalling, proliferation markers and gene expression, using microarrays, immunoblotting, immunohistochemistry and ELISA. Confocal microscopy, reporter assay, immunoprecipitation, immunoblotting, ion flux assays and holographic imaging were used to determine effects on colon cancer cells. Results Peroral HAMLET administration reduced tumour progression and mortality in ApcMin/+ mice. HAMLET accumulated specifically in tumour tissue, reduced β-catenin and related tumour markers. Gene expression analysis detected inhibition of Wnt signalling and a shift to a more differentiated phenotype. In colon cancer cells with APC mutations, HAMLET altered β-catenin integrity and localisation through an ion channel-dependent pathway, defining a new mechanism for controlling β-catenin signalling. Remarkably, supplying HAMLET to the drinking water from the time of weaning also significantly prevented tumour development. Conclusions These data identify HAMLET as a new, peroral agent for colon cancer prevention and treatment, especially needed in people carrying APC mutations, where colon cancer remains a leading cause of death. PMID:23348960

  20. Air pollution upregulates endothelial cell procoagulant activity via ultrafine particle-induced oxidant signaling and tissue factor expression.

    PubMed

    Snow, S J; Cheng, W; Wolberg, A S; Carraway, M S

    2014-07-01

    Air pollution exposure is associated with cardiovascular events triggered by clot formation. Endothelial activation and initiation of coagulation are pathophysiological mechanisms that could link inhaled air pollutants to vascular events. Here we investigated the underlying mechanisms of increased endothelial cell procoagulant activity following exposure to soluble components of ultrafine particles (soluble UF). Human coronary artery endothelial cells (HCAEC) were exposed to soluble UF and assessed for their ability to trigger procoagulant activity in platelet-free plasma. Exposed HCAEC triggered earlier thrombin generation and faster fibrin clot formation, which was abolished by an anti-tissue factor (TF) antibody, indicating TF-dependent effects. Soluble UF exposure increased TF mRNA expression without compensatory increases in key anticoagulant proteins. To identify early events that regulate TF expression, we measured endothelial H2O2 production following soluble UF exposure and identified the enzymatic source. Soluble UF exposure increased endothelial H2O2 production, and antioxidants attenuated UF-induced upregulation of TF, linking the procoagulant responses to reactive oxygen species (ROS) formation. Chemical inhibitors and RNA silencing showed that NOX-4, an important endothelial source of H2O2, was involved in UF-induced upregulation of TF mRNA. These data indicate that soluble UF exposure induces endothelial cell procoagulant activity, which involves de novo TF synthesis, ROS production, and the NOX-4 enzyme. These findings provide mechanistic insight into the adverse cardiovascular effects associated with air pollution exposure.

  1. Air pollution upregulates endothelial cell procoagulant activity via ultrafine particle-induced oxidant signaling and tissue factor expression.

    PubMed

    Snow, S J; Cheng, W; Wolberg, A S; Carraway, M S

    2014-07-01

    Air pollution exposure is associated with cardiovascular events triggered by clot formation. Endothelial activation and initiation of coagulation are pathophysiological mechanisms that could link inhaled air pollutants to vascular events. Here we investigated the underlying mechanisms of increased endothelial cell procoagulant activity following exposure to soluble components of ultrafine particles (soluble UF). Human coronary artery endothelial cells (HCAEC) were exposed to soluble UF and assessed for their ability to trigger procoagulant activity in platelet-free plasma. Exposed HCAEC triggered earlier thrombin generation and faster fibrin clot formation, which was abolished by an anti-tissue factor (TF) antibody, indicating TF-dependent effects. Soluble UF exposure increased TF mRNA expression without compensatory increases in key anticoagulant proteins. To identify early events that regulate TF expression, we measured endothelial H2O2 production following soluble UF exposure and identified the enzymatic source. Soluble UF exposure increased endothelial H2O2 production, and antioxidants attenuated UF-induced upregulation of TF, linking the procoagulant responses to reactive oxygen species (ROS) formation. Chemical inhibitors and RNA silencing showed that NOX-4, an important endothelial source of H2O2, was involved in UF-induced upregulation of TF mRNA. These data indicate that soluble UF exposure induces endothelial cell procoagulant activity, which involves de novo TF synthesis, ROS production, and the NOX-4 enzyme. These findings provide mechanistic insight into the adverse cardiovascular effects associated with air pollution exposure. PMID:24752501

  2. α-Tocopherol administration blocks adaptive changes in cell NADH/NAD+ redox state and mitochondrial function leading to inhibition of gastric mucosa cell proliferation in rats.

    PubMed

    Olguín-Martínez, Marisela; Hernández-Espinosa, Diego R; Hernández-Muñoz, Rolando

    2013-12-01

    In experimentally induced chronic gastritis, a compensatory mucosal cell proliferation occurs with enhanced glucose oxidative metabolism linked to lipoperoxidative events. Therefore, this study was aimed at assessing the participation of cell NAD/NADH redox state and mitochondrial functions during gastric mucosa proliferation and the effects of in vivo α-tocopherol (vitamin E) administration. Glucose oxidation and oxygen consumption were tested in gastric mucosa samples obtained from rats with gastritis and from those also treated with α-tocopherol. Gastric mucosal mitochondria were isolated and structural and functional parameters were determined. Succinate oxidation, ADP phosphorylation, mitochondrial enzyme activities, and membrane lipid composition were measured. In addition, parameters indicative of cellular NAD/NADH redox state, proliferation, apoptosis, and nitric oxide (NO) metabolism were also determined. After ethanol withdrawal, the damaged gastric mucosa increased glucose and oxygen consumption, events associated with a more reduced cytoplasmic NAD/NADH ratio. Enhanced mitochondrial oxidative phosphorylation and increased mitochondrial enzyme activities occurred early, accompanied by recovery of lost mitochondrial protein and lipid composition in the gastric mucosa, events associated with increased NO production. When mitochondrial function and structural events were normalized, apoptosis was initiated as assessed by the mitochondrial Bax/Bcl2 ratio. Treatment with α-tocopherol inhibited cell proliferation and blocked enhanced glucose utilization, mitochondrial substrate oxidation, and changes in redox state, delaying the onset of these adaptive metabolic changes, whereas it inhibited cell proliferation. In conclusion, α-tocopherol could abolish damage-induced "stress" signaling by desynchronizing mitochondrial adaptive responses, including mitochondria biogenesis, and consequently NAD/NADH redox, which seems to regulate gastric mucosal cell

  3. α-Tocopherol administration blocks adaptive changes in cell NADH/NAD+ redox state and mitochondrial function leading to inhibition of gastric mucosa cell proliferation in rats.

    PubMed

    Olguín-Martínez, Marisela; Hernández-Espinosa, Diego R; Hernández-Muñoz, Rolando

    2013-12-01

    In experimentally induced chronic gastritis, a compensatory mucosal cell proliferation occurs with enhanced glucose oxidative metabolism linked to lipoperoxidative events. Therefore, this study was aimed at assessing the participation of cell NAD/NADH redox state and mitochondrial functions during gastric mucosa proliferation and the effects of in vivo α-tocopherol (vitamin E) administration. Glucose oxidation and oxygen consumption were tested in gastric mucosa samples obtained from rats with gastritis and from those also treated with α-tocopherol. Gastric mucosal mitochondria were isolated and structural and functional parameters were determined. Succinate oxidation, ADP phosphorylation, mitochondrial enzyme activities, and membrane lipid composition were measured. In addition, parameters indicative of cellular NAD/NADH redox state, proliferation, apoptosis, and nitric oxide (NO) metabolism were also determined. After ethanol withdrawal, the damaged gastric mucosa increased glucose and oxygen consumption, events associated with a more reduced cytoplasmic NAD/NADH ratio. Enhanced mitochondrial oxidative phosphorylation and increased mitochondrial enzyme activities occurred early, accompanied by recovery of lost mitochondrial protein and lipid composition in the gastric mucosa, events associated with increased NO production. When mitochondrial function and structural events were normalized, apoptosis was initiated as assessed by the mitochondrial Bax/Bcl2 ratio. Treatment with α-tocopherol inhibited cell proliferation and blocked enhanced glucose utilization, mitochondrial substrate oxidation, and changes in redox state, delaying the onset of these adaptive metabolic changes, whereas it inhibited cell proliferation. In conclusion, α-tocopherol could abolish damage-induced "stress" signaling by desynchronizing mitochondrial adaptive responses, including mitochondria biogenesis, and consequently NAD/NADH redox, which seems to regulate gastric mucosal cell

  4. Treatment of poly(ethylene terephthalate) foils by atmospheric pressure air dielectric barrier discharge and its influence on cell growth

    NASA Astrophysics Data System (ADS)

    Kuzminova, Anna; Vandrovcová, Marta; Shelemin, Artem; Kylián, Ondřej; Choukourov, Andrei; Hanuš, Jan; Bačáková, Lucie; Slavínská, Danka; Biederman, Hynek

    2015-12-01

    In this contribution an effect of dielectric barrier discharge (DBD) sustained in air at atmospheric pressure on surface properties of poly(ethylene terephthalate) (PET) foils is studied. It is found that exposure of PET to DBD plasma leads to rapid changes of surface chemical composition, wettability, surface morphology as well as mechanical properties of PET surface. In addition, based on biological tests that were performed using two cell types (Saos-2 human osteoblast-like cells and HUVEC human umbilical vein endothelial cells), it may be concluded that DBD plasma treatment positively influences cell growth on PET. This effect was found to be connected predominantly with increased surface energy and oxygen content of the surface of treated PET foils.

  5. The 2006 Cape Canaveral Air Force Station Range Reference Atmosphere Model Validation Study and Sensitivity Analysis to the National Aeronautics and Space Administration's Space Shuttle

    NASA Technical Reports Server (NTRS)

    Decker, Ryan; Burns, Lee; Merry, Carl; Harrington, Brian

    2008-01-01

    NASA's Space Shuttle utilizes atmospheric thermodynamic properties to evaluate structural dynamics and vehicle flight performance impacts by the atmosphere during ascent. Statistical characteristics of atmospheric thermodynamic properties at Kennedy Space Center (KSC) used in Space. Shuttle Vehicle assessments are contained in the Cape Canaveral Air Force Station (CCAFS) Range Reference Atmosphere (RRA) Database. Database contains tabulations for monthly and annual means (mu), standard deviations (sigma) and skewness of wind and thermodynamic variables. Wind, Thermodynamic, Humidity and Hydrostatic parameters 1 km resolution interval from 0-30 km 2 km resolution interval 30-70 km Multiple revisions of the CCAFS RRA database have been developed since initial RRA published in 1963. 1971, 1983, 2006 Space Shuttle program utilized 1983 version for use in deriving "hot" and "cold" atmospheres, atmospheric density dispersions for use in vehicle certification analyses and selection of atmospheric thermodynamic profiles for use in vehicle ascent design and certification analyses. During STS-114 launch preparations in July 2005 atmospheric density observations between 50-80 kft exceeded density limits used for aerodynamic ascent heating constraints in vehicle certification analyses. Mission specific analyses were conducted and concluded that the density bias resulted in small changes to heating rates and integrated heat loading on the vehicle. In 2001, the Air Force Combat Climatology Center began developing an updated RRA for CCAFS.

  6. Local administration of granulocyte macrophage colony-stimulating factor induces local accumulation of dendritic cells and antigen-specific CD8+ T cells and enhances dendritic cell cross-presentation

    PubMed Central

    Lee, Sung-Jong; Song, Liwen; Yang, Ming-Cheh; Mao, Chih-Ping; Yang, Benjamin; Yang, Andrew; Jeang, Jessica; Peng, Shiwen; Wu, T.-C.; Hung, Chien-Fu

    2015-01-01

    Immunotherapy has emerged as a promising treatment strategy for the control of HPV-associated malignancies. Various therapeutic HPV vaccines have elicited potent antigen-specific CD8+ T cell mediated antitumor immune responses in preclinical models and are currently being tested in several clinical trials. Recent evidence indicates the importance of local immune activation, and higher number of immune cells in the site of lesion correlates with positive prognosis. Granulocyte macrophage colony-stimulating factor (GMCSF) has been reported to posses the ability to induce migration of antigen presentation cells and CD8+ T cells. Therefore, in the current study, we employ a combination of systemic therapeutic HPV DNA vaccination with local GMCSF application in the TC-1 tumor model. We show that intramuscular vaccination with CRT/E7 DNA followed by GMCSF intravaginal administration effectively controls cervicovaginal TC-1 tumors in mice. Furthermore, we observe an increase in the accumulation of E7-specific CD8+ T cells and dendritic cells in vaginal tumors following the combination treatment. In addition, we show that GMCSF induces activation and maturation in dendritic cells and promotes antigen cross-presentation. Our results support the clinical translation of the combination treatment of systemic therapeutic vaccination followed by local GMCSF administration as an effective strategy for tumor treatment. PMID:25701675

  7. Implementation of air quality control in reproductive laboratories in full compliance with the Brazilian Cells and Germinative Tissue Directive.

    PubMed

    Esteves, Sandro C; Bento, Fabiola C

    2013-01-01

    This article describes how Androfert complied with the Brazilian Cells and Germinative Tissue Directive with regard to air quality standards and presents retrospective data of intracytoplasmic sperm injection (ICSI) outcomes performed in controlled environments. An IVF facility, composed of reproductive laboratories, operating room and embryo-transfer room, was constructed according to cleanroom standards for air particles and volatile organic compounds. A total of 2060 couples requesting IVF were treated in the cleanroom facilities, and outcome measures compared with a cohort of 255 couples treated at a conventional facility from the same practice before implementation of cleanrooms. No major fluctuations were observed in the cleanroom validation measurements over the study period. Live birth rates increased (35.6% versus 25.8%; P=0.02) and miscarriage rates decreased (28.7% versus 20.0%; P=0.04) in the first triennium after cleanroom implementation. Thereafter, the proportion of high-quality embryos steadily increased whereas pregnancy outcomes after ICSI were sustained despite the increased female age and decreased number of embryos transferred. This study demonstrates the feasibility of handling human gametes and culturing embryos in full compliance with the Brazilian directive on air quality standards and suggests that performing IVF in controlled environments may optimize its outcomes. Regulatory agencies in many countries have issued directives including specific requirements for air quality standards in embryology facilities. This article describes how we complied with the Brazilian Cells and Germinative Tissue Directive with regard to air quality standards. It also presents results of IVF cycles performed in controlled environments. An IVF facility, composed of reproductive laboratories, operating room and embryo transfer room, was constructed according to cleanroom standards for air particles and volatile organic compounds. The cleanest area was the

  8. Air Force Ni-H2 cell test program: State of Charge test

    NASA Technical Reports Server (NTRS)

    Moore, Bruce; Smellie, Douglas

    1995-01-01

    Nickel-Hydrogen cells are being cycled under a LEO (low earth orbit) test regime to examine the benefits of operating the cells at lower States of Charge (SOC) than typically used. A group of four cells are cycled using a voltage limiting charge regime that limits the State of Charge that the cells are allowed to reach. The test cells are then compared to identical cells being cycled at or near 100% State of Charge using a constant current charge regime.

  9. Intrathecal Administration of Mesenchymal Stem Cells Reduces the Reactive Oxygen Species and Pain Behavior in Neuropathic Rats

    PubMed Central

    Zhang, En Ji; Ko, Young Kwon

    2014-01-01

    Background Neuropathic pain induced by spinal or peripheral nerve injury is very resistant to common pain killers, nerve block, and other pain management approaches. Recently, several studies using stem cells suggested a new way to control the neuropatic pain. In this study, we used the spinal nerve L5 ligation (SNL) model to investigate whether intrathecal rat mesenchymal stem cells (rMSCs) were able to decrease pain behavior, as well as the relationship between rMSCs and reactive oxygen species (ROS). Methods Neuropathic pain of the left hind paw was induced by unilateral SNL in Sprague-Dawley rats (n = 10 in each group). Mechanical sensitivity was assessed using Von Frey filaments at 3, 7, 10, 12, 14, 17, and 24 days post-ligation. rMSCs (10 µl, 1 × 105) or phosphate buffer saline (PBS, 10 µl) was injected intrathecally at 7 days post-ligation. Dihydroethidium (DHE), an oxidative fluorescent dye, was used to detect ROS at 24 days post-ligation. Results Tight ligation of the L5 spinal nerve induced allodynia in the left hind paw after 3 days post-ligation. ROS expression was increased significantly (P < 0.05) in spinal dorsal horn of L5. Intrathecal rMSCs significantly (P < 0.01) alleviated the allodynia at 10 days after intrathecal injection (17 days post-ligation). Intrathecal rMSCs administration significantly (P < 0.05) reduced ROS expression in the spinal dorsal horn. Conclusions These results suggest that rMSCs may modulate neuropathic pain generation through ROS expression after spinal nerve ligation. PMID:25031809

  10. Effects of Intracoronary Administration of Autologous Adipose Tissue-Derived Stem Cells on Acute Myocardial Infarction in a Porcine Model

    PubMed Central

    Lee, Hye Won; Park, Jong Ha; Kim, Bo Won; Ahn, Jinhee; Kim, Jin Hee; Park, Jin Sup; Oh, Jun-Hyok; Choi, Jung Hyun; Cha, Kwang Soo; Hong, Taek Jong; Park, Tae Sik; Kim, Sang-Pil; Song, Seunghwan; Kim, Ji Yeon; Park, Mi Hwa; Jung, Jin Sup

    2015-01-01

    Purpose Adipose-derived stem cells (ADSCs) are known to be potentially effective in regeneration of damaged tissue. We aimed to assess the effectiveness of intracoronary administration of ADSCs in reducing the infarction area and improving function after acute transmural myocardial infarction (MI) in a porcine model. Materials and Methods ADSCs were obtained from each pig's abdominal subcutaneous fat tissue by simple liposuction. After 3 passages of 14-days culture, 2 million ADSCs were injected into the coronary artery 30 min after acute transmural MI. At baseline and 4 weeks after the ADSC injection, 99mTc methoxyisobutylisonitrile-single photon emission computed tomography (MIBI-SPECT) was performed to evaluate the left ventricular volume, left ventricular ejection fraction (LVEF; %), and perfusion defects as well as the myocardial salvage (%) and salvage index. At 4 weeks, each pig was sacrificed, and the heart was extracted and dissected. Gross and microscopic analyses with specific immunohistochemistry staining were then performed. Results Analysis showed improvement in the perfusion defect, but not in the LVEF in the ADSC group (n=14), compared with the control group (n=14) (perfusion defect, -13.0±10.0 vs. -2.6±12.0, p=0.019; LVEF, -8.0±15.4 vs. -15.9±14.8, p=0.181). There was a tendency of reducing left ventricular volume in ADSC group. The ADSCs identified by stromal cell-derived factor-1 (SDF-1) staining were well co-localized by von Willebrand factor and Troponin T staining. Conclusion Intracoronary injection of cultured ADSCs improved myocardial perfusion in this porcine acute transmural MI model. PMID:26446632

  11. Inhibition of microbial growth on air cathodes of single chamber microbial fuel cells by incorporating enrofloxacin into the catalyst layer.

    PubMed

    Liu, Weifeng; Cheng, Shaoan; Sun, Dan; Huang, Haobin; Chen, Jie; Cen, Kefa

    2015-10-15

    The inevitable growth of aerobic bacteria on the surface of air cathodes is an important factor reducing the performance stability of air cathode single-chamber membrane-free microbial fuel cells (MFCs). Thus searching for effective methods to inhibit the cathodic microbial growth is critical for the practical application of MFCs. In this study, enrofloxacin (ENR), a broad spectrum fluoroquinolone antibiotic, was incorporated into the catalyst layer of activated carbon air cathodes (ACACs) to inhibit the cathodic microbial growth. The biomass content on ACACs was substantially reduced by 60.2% with ENR treatment after 91 days of MFCs operation. As a result of the inhibited microbial growth, the oxygen reduction catalytic performance of the ENR treated ACACs was much stable compared to the fast performance decline of the untreated control. Consequently, a quite stable electricity production was obtained for the MFCs with the ENR treated ACACs, in contrast with a 22.5% decrease in maximum power density of the MFCs with the untreated cathode. ENR treatment of ACACs showed minimal effects on the anode performance. These results indicate that incorporating antibiotics into ACACs should be a simple and effective strategy to inhibit the microbial growth and improve the long-term stability of the performance of air cathode and the electricity production of MFCs.

  12. AirLab: a cloud-based platform to manage and share antibody-based single-cell research.

    PubMed

    Catena, Raúl; Özcan, Alaz; Jacobs, Andrea; Chevrier, Stephane; Bodenmiller, Bernd

    2016-01-01

    Single-cell analysis technologies are essential tools in research and clinical diagnostics. These methods include flow cytometry, mass cytometry, and other microfluidics-based technologies. Most laboratories that employ these methods maintain large repositories of antibodies. These ever-growing collections of antibodies, their multiple conjugates, and the large amounts of data generated in assays using specific antibodies and conditions makes a dedicated software solution necessary. We have developed AirLab, a cloud-based tool with web and mobile interfaces, for the organization of these data. AirLab streamlines the processes of antibody purchase, organization, and storage, antibody panel creation, results logging, and antibody validation data sharing and distribution. Furthermore, AirLab enables inventory of other laboratory stocks, such as primers or clinical samples, through user-controlled customization. Thus, AirLab is a mobile-powered and flexible tool that harnesses the capabilities of mobile tools and cloud-based technology to facilitate inventory and sharing of antibody and sample collections and associated validation data. PMID:27356760

  13. Legal and security requirements for the air transportation of cyanotoxins and toxigenic cyanobacterial cells for legitimate research and analytical purposes.

    PubMed

    Metcalf, J S; Meriluoto, J A O; Codd, G A

    2006-05-25

    Cyanotoxins are now recognised by international and national health and environment agencies as significant health hazards. These toxins, and the cells which produce them, are also vulnerable to exploitation for illegitimate purposes. Cyanotoxins are increasingly being subjected to national and international guidelines and regulations governing their production, storage, packaging and transportation. In all of these respects, cyanotoxins are coming under the types of controls imposed on a wide range of chemicals and other biotoxins of microbial, plant and animal origin. These controls apply whether cyanotoxins are supplied on a commercial basis, or stored and transported in non-commercial research collaborations and programmes. Included are requirements concerning the transportation of these toxins as documented by the United Nations, the International Air Transport Association (IATA) and national government regulations. The transportation regulations for "dangerous goods", which by definition include cyanotoxins, cover air mail, air freight, and goods checked in and carried on flights. Substances include those of determined toxicity and others of suspected or undetermined toxicity, covering purified cyanotoxins, cyanotoxin-producing laboratory strains and environmental samples of cyanobacteria. Implications of the regulations for the packaging and air-transport of dangerous goods, as they apply to cyanotoxins and toxigenic cyanobacteria, are discussed.

  14. External CO2 and water supplies for enhancing electrical power generation of air-cathode microbial fuel cells.

    PubMed

    Ishizaki, So; Fujiki, Itto; Sano, Daisuke; Okabe, Satoshi

    2014-10-01

    Alkalization on the cathode electrode limits the electrical power generation of air-cathode microbial fuel cells (MFCs), and thus external proton supply to the cathode electrode is essential to enhance the electrical power generation. In this study, the effects of external CO2 and water supplies to the cathode electrode on the electrical power generation were investigated, and then the relative contributions of CO2 and water supplies to the total proton consumption were experimentally evaluated. The CO2 supply decreased the cathode pH and consequently increased the power generation. Carbonate dissolution was the main proton source under ambient air conditions, which provides about 67% of total protons consumed for the cathode reaction. It is also critical to adequately control the water content on the cathode electrode of air-cathode MFCs because the carbonate dissolution was highly dependent on water content. On the basis of these experimental results, the power density was increased by 400% (143.0 ± 3.5 mW/m(2) to 575.0 ± 36.0 mW/m(2)) by supplying a humid gas containing 50% CO2 to the cathode chamber. This study demonstrates that the simultaneous CO2 and water supplies to the cathode electrode were effective to increase the electrical power generation of air-cathode MFCs for the first time.

  15. Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the Federal Transit Administration (Report and Appendix)

    SciTech Connect

    Eudy, L.; Chandler, K.

    2010-11-01

    This document describes the fuel cell transit bus evaluations performed by the National Renewable Energy Laboratory (NREL) and funded by the U.S. Department of Energy (DOE) and the U.S. Department of Transportation's Federal Transit Administration (FTA). This document provides a description of the demonstration sites, funding sources, and data collection activities for fuel cell transit bus evaluations currently planned from FY10 through FY12.

  16. Step-Scan T-Cell Fourier Transform Infrared Photoacoustic Spectroscopy (FTIR-PAS) for Monitoring Environmental Air Pollutants

    NASA Astrophysics Data System (ADS)

    Liu, Lixian; Mandelis, Andreas; Melnikov, Alexander; Michaelian, Kirk; Huan, Huiting; Haisch, Christoph

    2016-07-01

    Air pollutants have adverse effects on the Earth's climate system. There is an urgent need for cost-effective devices capable of recognizing and detecting various ambient pollutants. An FTIR photoacoustic spectroscopy (FTIR-PAS) method based on a commercial FTIR spectrometer developed for air contamination monitoring will be presented. A resonant T-cell was determined to be the most appropriate resonator in view of the low-frequency requirement and space limitations in the sample compartment. Step-scan FTIR-PAS theory for regular cylinder resonator has been described as a reference for prediction of T-cell vibration principles. Both simulated amplitude and phase responses of the T-cell show good agreement with measurement data Carbon dioxide IR absorption spectra were used to demonstrate the capacity of the FTIR-PAS method to detect ambient pollutants. The theoretical detection limit for carbon dioxide was found to be 4 ppmv. A linear response to carbon dioxide concentration was found in the range from 2500 ppmv to 5000 ppmv. The results indicate that it is possible to use step-scan FTIR-PAS with a T-cell as a quantitative method for analysis of ambient contaminants.

  17. CO2 Fixation, Lipid Production, and Power Generation by a Novel Air-Lift-Type Microbial Carbon Capture Cell System.

    PubMed

    Hu, Xia; Liu, Baojun; Zhou, Jiti; Jin, Ruofei; Qiao, Sen; Liu, Guangfei

    2015-09-01

    An air-lift-type microbial carbon capture cell (ALMCC) was constructed for the first time by using an air-lift-type photobioreactor as the cathode chamber. The performance of ALMCC in fixing high concentration of CO2, producing energy (power and biodiesel), and removing COD together with nutrients was investigated and compared with the traditional microbial carbon capture cell (MCC) and air-lift-type photobioreactor (ALP). The ALMCC system produced a maximum power density of 972.5 mW·m(-3) and removed 86.69% of COD, 70.52% of ammonium nitrogen, and 69.24% of phosphorus, which indicate that ALMCC performed better than MCC in terms of power generation and wastewater treatment efficiency. Besides, ALMCC demonstrated 9.98- and 1.88-fold increases over ALP and MCC in the CO2 fixation rate, respectively. Similarly, the ALMCC significantly presented a higher lipid productivity compared to those control reactors. More importantly, the preliminary analysis of energy balance suggested that the net energy of the ALMCC system was significantly superior to other systems and could theoretically produce enough energy to cover its consumption. In this work, the established ALMCC system simultaneously achieved the high level of CO2 fixation, energy recycle, and municipal wastewater treatment effectively and efficiently.

  18. Effect of indoor air pollution from biomass fuel use on argyrophilic nuclear organizer regions in buccal epithelial cells.

    PubMed

    Mondal, Nandan K; Dutta, Anindita; Banerjee, Anirban; Chakraborty, Sreeparna; Lahiri, Twisha; Ray, Manas Ranjan

    2009-01-01

    This study investigated the effect of indoor air pollution from biomass-fuel use on the expression of argyrophilic nucleolar organizer regions (AgNORs), an indicator of ribosome biosynthesis, in epithelial cells of oral mucosa. AgNORs were evaluated using cytochemical staining in 62 nonsmoking indian women (median age, 34 years), who cooked exclusively with biomass, and 55 age-matched women, who were from a similar neighborhood and cooked with relatively clean liquefied petroleum gas (LPG). Concentrations of particulate pollutants in indoor air were measured using a real-time aerosol monitor. Compared to the LPG-using controls, biomass-fuel users showed a remarkably increased number of AgNOR dots per nucleus (6.08 +/-2.26 vs 3.16 +/-0.86, p < 0.001), AgNOR size (0.85 +/-0.19 vs 0.53 +/-0.15 mum2, p < 0.001), and percentage of AgNOR-occupied nuclear area (4.88 +/-1.49 vs 1.75 +/-0.13%, p < 0.001). Biomass-using households had 2 to 4 times more particulate pollutants than that of LPG-using households. The changes in AgNOR expression were positively associated with PM10 and PM2.5 levels in indoor air after controlling for potential confounders such as age, kitchen location, and family income. Thus, biomass smoke appears to be a risk factor for abnormal cell growth via upregulation of ribosome biogenesis.

  19. Gold Nanorods Based Air Scanning Electron Microscopy and Diffusion Reflection Imaging for Mapping Tumor Margins in Squamous Cell Carcinoma.

    PubMed

    Ankri, Rinat; Ashkenazy, Ariel; Milstein, Yonat; Brami, Yaniv; Olshinka, Asaf; Goldenberg-Cohen, Nitza; Popovtzer, Aron; Fixler, Dror; Hirshberg, Abraham

    2016-02-23

    A critical challenge arising during a surgical procedure for tumor removal is the determination of tumor margins. Gold nanorods (GNRs) conjugated to epidermal growth factor receptors (EGFR) (GNRs-EGFR) have long been used in the detection of cancerous cells as the expression of EGFR dramatically increases once the tissue becomes cancerous. Optical techniques for the identification of these GNRs-EGFR in tumor are intensively developed based on the unique scattering and absorption properties of the GNRs. In this study, we investigate the distribution of the GNRs in tissue sections presenting squamous cell carcinoma (SCC) to evaluate the SCC margins. Air scanning electron microscopy (airSEM), a novel, high resolution microscopy is used, enabling to localize and actually visualize nanoparticles on the tissue. The airSEM pictures presented a gradient of GNRs from the tumor to normal epithelium, spread in an area of 1 mm, suggesting tumor margins of 1 mm. Diffusion reflection (DR) measurements, performed in a resolution of 1 mm, of human oral SCC have shown a clear difference between the DR profiles of the healthy epithelium and the tumor itself. PMID:26759920

  20. The SPECT imaging shows the accumulation of neural progenitor cells into internal organs after systemic administration in middle cerebral artery occlusion rats.

    PubMed

    Lappalainen, Riikka S; Narkilahti, Susanna; Huhtala, Tuulia; Liimatainen, Timo; Suuronen, Tiina; Närvänen, Ale; Suuronen, Riitta; Hovatta, Outi; Jolkkonen, Jukka

    2008-08-01

    The regenerative potential of stem cells from various sources has been under intense investigation in the experimental models of cerebral ischemia. To end up with a restorative therapeutic treatment, it is crucial to get the cell transplants to the site of injury. Here, we evaluated the feasibility of small animal SPECT/CT in assessing the definite accumulation of (111)In-oxine-labeled human embryonic stem (ES) cell-derived neural progenitors and rat hippocampal progenitors after intravenous or intra-arterial administration (femoral vein vs. common carotid artery) in middle cerebral artery occlusion (MCAO) and sham-operated rats. Cell detection was carried out immediately and 24h after the infusion using a SPECT/CT device. The results showed that after intravenous injections both cell types accumulated primarily into internal organs, instead of brain. In contrast, after intra-arterial injection, a weak signal was detected in the ischemic hemisphere. Additional studies showed that the detection sensitivity of SPECT/CT device was approximately 1000 (111)In-oxine-labeled cells and labeling did not affect the cell viability. In conclusion, a small animal SPECT is powerful technique to study the whole body biodistribution of cell-based therapies. Our data showed that intravenous administration is not an optimal route to deliver neural progenitor cell-containing transplants into the brain after MCAO in rats. PMID:18572314

  1. Comparison of different platelet count thresholds to guide administration of prophylactic platelet transfusion for preventing bleeding in patients with haematological disorders after chemotherapy or stem cell transplantation

    PubMed Central

    Estcourt, Lise J; Stanworth, Simon; Doree, Carolyn; Trivella, Marialena; Hopewell, Sally; Murphy, Michael F; Tinmouth, Alan

    2014-01-01

    This is the protocol for a review and there is no abstract. The objectives are as follows: To determine whether different platelet transfusion thresholds for administration of prophylactic platelet transfusions (platelet transfusions given to prevent bleeding) affect the efficacy and safety of prophylactic platelet transfusions in preventing bleeding in patients with haematological disorders after chemotherapy with or without stem cell transplantation. PMID:25722651

  2. Influence of single and repeated cannabidiol administration on emotional behavior and markers of cell proliferation and neurogenesis in non-stressed mice.

    PubMed

    Schiavon, Angélica Pupin; Bonato, Jéssica Mendes; Milani, Humberto; Guimarães, Francisco Silveira; Weffort de Oliveira, Rúbia Maria

    2016-01-01

    Therapeutic effects of antidepressants and atypical antipsychotics may arise partially from their ability to stimulate neurogenesis. Cannabidiol (CBD), a phytocannabinoid present in Cannabis sativa, presents anxiolytic- and antipsychotic-like effects in preclinical and clinical settings. Anxiolytic-like effects of repeated CBD were shown in chronically stressed animals and these effects were parallel with increased hippocampal neurogenesis. However, antidepressant-like effects of repeated CBD administration in non-stressed animals have been scarcely reported. Here we investigated the behavioral consequences of single or repeated CBD administration in non-stressed animals. We also determined the effects of CBD on cell proliferation and neurogenesis in the dentate gyrus (DG) and subventricular zone (SVZ). Single CBD 3mg/kg administration resulted in anxiolytic-like effect in mice submitted to the elevated plus maze (EPM). In the tail suspension test (TST), single or repeated CBD administration reduced immobility time, an effect that was comparable to those of imipramine (20 mg/kg). Moreover, repeated CBD administration at a lower dose (3 mg/kg) increased cell proliferation and neurogenesis, as seen by an increased number of Ki-67-, BrdU- and doublecortin (DCX)-positive cells in both in DG and SVZ. Despite its antidepressant-like effects in the TST, repeated CBD administration at a higher dose (30 mg/kg) decreased cell proliferation and neurogenesis in the hippocampal DG and SVZ. Our findings show a dissociation between behavioral and proliferative effects of repeated CBD and suggest that the antidepressant-like effects of CBD may occur independently of adult neurogenesis in non-stressed Swiss mice.

  3. Influence of single and repeated cannabidiol administration on emotional behavior and markers of cell proliferation and neurogenesis in non-stressed mice.

    PubMed

    Schiavon, Angélica Pupin; Bonato, Jéssica Mendes; Milani, Humberto; Guimarães, Francisco Silveira; Weffort de Oliveira, Rúbia Maria

    2016-01-01

    Therapeutic effects of antidepressants and atypical antipsychotics may arise partially from their ability to stimulate neurogenesis. Cannabidiol (CBD), a phytocannabinoid present in Cannabis sativa, presents anxiolytic- and antipsychotic-like effects in preclinical and clinical settings. Anxiolytic-like effects of repeated CBD were shown in chronically stressed animals and these effects were parallel with increased hippocampal neurogenesis. However, antidepressant-like effects of repeated CBD administration in non-stressed animals have been scarcely reported. Here we investigated the behavioral consequences of single or repeated CBD administration in non-stressed animals. We also determined the effects of CBD on cell proliferation and neurogenesis in the dentate gyrus (DG) and subventricular zone (SVZ). Single CBD 3mg/kg administration resulted in anxiolytic-like effect in mice submitted to the elevated plus maze (EPM). In the tail suspension test (TST), single or repeated CBD administration reduced immobility time, an effect that was comparable to those of imipramine (20 mg/kg). Moreover, repeated CBD administration at a lower dose (3 mg/kg) increased cell proliferation and neurogenesis, as seen by an increased number of Ki-67-, BrdU- and doublecortin (DCX)-positive cells in both in DG and SVZ. Despite its antidepressant-like effects in the TST, repeated CBD administration at a higher dose (30 mg/kg) decreased cell proliferation and neurogenesis in the hippocampal DG and SVZ. Our findings show a dissociation between behavioral and proliferative effects of repeated CBD and suggest that the antidepressant-like effects of CBD may occur independently of adult neurogenesis in non-stressed Swiss mice. PMID:26187374

  4. Peroral administration of 5-bromo-2-deoxyuridine in drinking water is not a reliable method for labeling proliferating S-phase cells in rats.

    PubMed

    Ševc, Juraj; Matiašová, Anna; Smoleková, Ivana; Jendželovský, Rastislav; Mikeš, Jaromír; Tomášová, Lenka; Kútna, Viera; Daxnerová, Zuzana; Fedoročko, Peter

    2015-01-01

    In rodents, peroral (p.o.) administration of 5-bromo-2'-deoxyuridine (BrdU) dissolved in drinking water is a widely used method for labeling newly formed cells over a prolonged time-period. Despite the broad applicability of this method, the pharmacokinetics of BrdU in rats or mice after p.o. administration remains unknown. Moreover, the p.o. route of administration may be limited by the relatively low amount of BrdU consumed over 24h and the characteristic drinking pattern of rats, with water intake being observed predominantly during the dark phase. Therefore, we investigated the reliability of staining proliferating S-phase cells with BrdU after p.o. administration (1mg/ml) to rats using both in vitro and in vivo conditions. Flow cytometric analysis of tumor cells co-cultivated with sera from experimental animals exposed to BrdU dissolved in drinking water or 25% orange juice revealed that the concentration of BrdU in the blood sera of rats throughout the day was below the detection limits of our assay. Ingested BrdU was only sufficient to label approximately 4.2±0.3% (water) or 4.2±0.3% (25% juice) of all S-phase cells. Analysis of data from in vivo conditions indicates that only 7.6±3.3% or 15.5±2.3% of all S-phase cells in the dentate gyrus of the hippocampus was labeled in animals administered drinking water containing BrdU during the light and dark phases of the day. In addition, the intensity of BrdU-positive nuclei in animals receiving p.o. administration of BrdU was significantly lower than in control animals intraperitoneally injected with BrdU. Our data indicate that the conventional approach of p.o. administration of BrdU in the drinking water to rats provides strongly inaccurate information about the number of proliferating cells in target tissues. Therefore other administration routes, such as osmotic mini pumps, should be considered for labeling of proliferating cells over a prolonged time-period.

  5. Increased CD4+ T cell levels during IL-7 administration of antiretroviral therapy-treated simian immunodeficiency virus-positive macaques are not dependent on strong proliferative responses.

    PubMed

    Leone, Amanda; Rohankhedkar, Mukta; Okoye, Afam; Legasse, Alfred; Axthelm, Michael K; Villinger, Francois; Piatak, Michael; Lifson, Jeffrey D; Assouline, Brigitte; Morre, Michel; Picker, Louis J; Sodora, Donald L

    2010-08-01

    CD4(+) T cell depletion is a fundamental component of HIV infection and AIDS pathogenesis and is not always reversed following antiretroviral therapy (ART). In this study, the SIV-infected rhesus macaque model was used to assess recombinant simian IL-7 in its glycosylated form (rsIL-7gly) to enhance regeneration of CD4(+) T cells, particularly the crucial central memory compartment, after ART. We assessed the impact of rsIL-7gly administration as single injections and as a cluster of three doses. Irrespective of the dosing strategy used, the rsIL-7gly administration transiently increased proliferation of both central memory and naive cells, in both CD4(+) and CD8(+) subsets, without increasing SIV levels in the blood. Administration of rsIL-7gly at intervals of 4-6 wk maximized the proliferative response to therapy but resulted in only transient increases in peripheral blood T cell counts. Although more frequent rsIL-7gly "clustered" dosing (three times weekly with 2 wk of rest and then repeat) induced only an initial proliferative burst by CD4(+) T cells, this dosing strategy resulted in sustained increases in peripheral blood CD4(+) T cell counts. The clustered rsIL-7gly treatment regimen was shown to increase the half-life of a BrdU label among memory T cells in the blood when compared with that of macaques treated with ART alone, which is consistent with enhanced cell survival. These results indicate that dosing intervals have a major impact on the response to rsIL-7gly in SIV-positive ART-treated rhesus macaques and that optimum dosing strategies may be ones that induce CD4(+) T cell proliferation initially and provide increased CD4(+) T cell survival.

  6. 78 FR 49484 - Exchange of Air Force Real Property for Non-Air Force Real Property

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-14

    ... Department of Air Force Exchange of Air Force Real Property for Non-Air Force Real Property SUMMARY: Notice identifies excess Federal real property under administrative jurisdiction of the United States Air Force it... under the administrative jurisdiction of the Air Force. FOR FURTHER INFORMATION CONTACT: Mr....

  7. MWCNT-supported phthalocyanine cobalt as air-breathing cathodic catalyst in glucose/O2 fuel cells

    NASA Astrophysics Data System (ADS)

    Elouarzaki, Kamal; Haddad, Raoudha; Holzinger, Michael; Le Goff, Alan; Thery, Jessica; Cosnier, Serge

    2014-06-01

    Simple and highly efficient glucose fuel cells using abiotic catalysts and different ion exchange membranes were designed. The glucose fuel cells are based on a multi-walled carbon nanotube (MWCNT)-supported cobalt phthalocyanine (CoPc) cathode and a carbon black/platinum (C/Pt) anode. The electrocatalytic activity of the MWCNT/CoPc electrode for oxygen reduction was investigated by cyclic and linear sweep voltammetry. The electrochemical experiments show that CoPc exhibits promising catalytic properties for oxygen reduction due to its high overpotential and efficiency at reduced metal load. The MWCNT/CoPc electrodes were applied to the oxygen reduction reaction as air-breathing cathode in a single-chambered glucose fuel cell. This cathode was associated with a C/Pt anode in fuel cell configurations using either an anion (Nafion®) or a cation (Tokuyama) exchange membrane. The best fuel cell configuration delivered a maximum power density of 2.3 mW cm-2 and a cell voltage of 0.8 V in 0.5 M KOH solution containing 0.5 M glucose using the Tokuyama membrane at ambient conditions. Beside the highest power density per cathodic catalyst mass (383 W g-1), these glucose fuel cells exhibit a high operational stability, delivering 0.3 mW cm-2 after 50 days.

  8. DNA-PKcs interacts with Aire and regulates the expression of toll-like receptors in RAW264.7 cells.

    PubMed

    Wu, J; Zhu, W; Fu, H; Zhang, Y; Sun, J; Yang, W; Li, Y

    2012-05-01

    The autoimmune regulator (Aire) is a key mediator of the central tolerance for peripheral tissue self-antigen (PTAs) and is involved in the transcriptional control of many antigens in thymic medullary epithelial cells (mTECs). However, the function of Aire in peripheral lymphoid tissues and haematopoietic cells, particularly in monocytes and macrophages, remains poorly understood. We previously found that the expression of Toll-like receptor (TLR) 1, TLR3 and TLR8 was notably upregulated in pEGFPC1/Aire stably transfected RAW264.7 (GFP-Aire/RAW) cells, while the expressions of other TLRs were not significantly changed. The mechanism by which Aire affects TLR1, TLR3 and TLR8 expression is not clear. Interactions with other proteins, such as DNA-dependent protein kinase (DNA-PK), are crucial for regulating the transcriptional activity of Aire. In this study, we found that Aire and DNA-PK catalytic subunit (DNA-PKcs) were co-located in the nucleus of GFP-Aire/RAW cells, and they interact with each other. Small interfering RNA knock-down of DNA-PKcs in these cells decreased the expression of TLR1, TLR3 and TLR8, but no change was observed in pEGFPC1 stably transfected RAW264.7 (GFP/RAW) cells. We did not observe any change in the expressions of other TLRs after DNA-PKcs knock-down in GFP-Aire/RAW or GFP/RAW cells. A similar observation has been made in pEGFPC1/Aire or pEGFPC1 transiently transfected primary peritoneal macrophages. Using a luciferase activity assay, we found the that the transcriptional activity of TLR1, TLR3 and TLR8 promoters was also decreased after knock-down of DNA-PKcs in GFP-Aire/RAW cells. In conclusion, our results suggest that DNA-PKcs may interact with Aire to promote the expression of TLRs in RAW264.7 cells.

  9. Localisation of exogenous surfactants in cell membranes in the air-blood barrier: rat model.

    PubMed

    Marszałek, Andrzej; Biczysko, Wiesława; Wasowicz, Marcin; Surowiak, Paweł; Zabel, Maciej; Florek, Ewa

    2003-11-01

    The use of exogenous surfactants has been introduced into the therapy of patients of different ages. Much better results have been obtained in the treatment of respiratory distress syndrome with surfactants enriched with surfactant proteins. In the following study we used protein-containing surfactants (survanta and curosurf). The aim of the following study was to determine the localisation of artificial surfactants in the lung tissue. Using the Immunogold Technique, biotinylated surfactant proteins were traced in the air-blood barriers. In all lungs the exogenous surfactant was present only in some alveoli. In these parts small areas of atelectasis as well as oedema and transudate accumulation were seen. These changes were less severe after biotinylated curosurf treatment. In electron microscope studies we found surfactant elements in the air-blood barrier and other structures of the alveolar septa. Immunogold studies confirm the presence of biotynylated surfactant in the elements of the air-blood barrier. PMID:14655120

  10. Expression profile of peripheral tissue antigen genes in medullary thymic epithelial cells (mTECs) is dependent on mRNA levels of autoimmune regulator (Aire).

    PubMed

    Oliveira, Ernna H; Macedo, Claudia; Donate, Paula B; Almeida, Renata S; Pezzi, Nicole; Nguyen, Catherine; Rossi, Marcos A; Sakamoto-Hojo, Elza T; Donadi, Eduardo A; Passos, Geraldo A

    2013-01-01

    In the thymus of non-obese diabetic (NOD) mice, the expression of the autoimmune regulator (Aire) gene varies with age, and its down-regulation in young mice precedes the later emergence of type 1 diabetes mellitus (T1D). In addition, the insulin (Ins2) peripheral tissue antigen (PTA) gene, which is Aire-dependent, is also deregulated in these mice. Based in these findings, we hypothesized that the imbalance in PTA gene expression in the thymus can be associated with slight variations in Aire transcript levels. To test this, we used siRNA to knockdown Aire by in vivo electro-transfection of the thymus of BALB/c mice. The efficiency of the electro-transfection was monitored by assessing the presence of irrelevant Cy3-labeled siRNA in the thymic stroma. Importantly, Aire-siRNA reached medullary thymic epithelial cells (mTECs) down-regulating Aire. As expected, the in vivo Aire knockdown was partial and transient; the maximum 59% inhibition occurred in 48 h. The Aire knockdown was sufficient to down-regulate PTA genes; however, surprisingly, several others, including Ins2, were up-regulated. The modulation of these genes after in vivo Aire knockdown was comparable to that observed in NOD mice before the emergence of T1D. The in vitro transfections of 3.10 mTEC cells with Aire siRNA resulted in samples featuring partial (69%) and complete (100%) Aire knockdown. In these Aire siRNA-transfected 3.10 mTECs, the expression of PTA genes, including Ins2, was down-regulated. This suggests that the expression profile of PTA genes in mTECs is affected by fine changes in the transcription level of Aire.

  11. The electrolyte challenge for a direct methanol-air polymer electrolyte fuel cell operating at temperatures up to 200 C

    NASA Technical Reports Server (NTRS)

    Savinell, Robert; Yeager, Ernest; Tryk, Donald; Landau, Uziel; Wainright, Jesse; Gervasio, Dominic; Cahan, Boris; Litt, Morton; Rogers, Charles; Scherson, Daniel

    1993-01-01

    Novel polymer electrolytes are being evaluated for use in a direct methanol-air fuel cell operating at temperatures in excess of 100 C. The evaluation includes tests of thermal stability, ionic conductivity, and vapor transport characteristics. The preliminary results obtained to date indicate that a high temperature polymer electrolyte fuel cell is feasible. For example, Nafion 117 when equilibrated with phosphoric acid has a conductivity of at least 0.4 Omega(exp -1)cm(exp -1) at temperatures up to 200 C in the presence of 400 torr of water vapor and methanol vapor cross over equivalent to 1 mA/cm(exp 2) under a one atmosphere methanol pressure differential at 135 C. Novel polymers are also showing similar encouraging results. The flexibility to modify and optimize the properties by custom synthesis of these novel polymers presents an exciting opportunity to develop an efficient and compact methanol fuel cell.

  12. Perspective: Maintaining surface-phase purity is key to efficient open air fabricated cuprous oxide solar cells

    SciTech Connect

    Hoye, Robert L. Z. E-mail: jld35@cam.ac.uk; Ievskaya, Yulia; MacManus-Driscoll, Judith L. E-mail: jld35@cam.ac.uk; Brandt, Riley E.; Buonassisi, Tonio; Heffernan, Shane; Musselman, Kevin P.

    2015-02-01

    Electrochemically deposited Cu{sub 2}O solar cells are receiving growing attention owing to a recent doubling in efficiency. This was enabled by the controlled chemical environment used in depositing doped ZnO layers by atomic layer deposition, which is not well suited to large-scale industrial production. While open air fabrication with atmospheric pressure spatial atomic layer deposition overcomes this limitation, we find that this approach is limited by an inability to remove the detrimental CuO layer that forms on the Cu{sub 2}O surface. Herein, we propose strategies for achieving efficiencies in atmospherically processed cells that are equivalent to the high values achieved in vacuum processed cells.

  13. Critical importance of humidification of the anode in miniature air-breathing polymer electrolyte membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Hamel, Simon; Fréchette, Luc G.

    2011-08-01

    Although water management at the cathode is known to be critical in miniature polymer electrolyte membrane fuel cells (mPEMFCs), this study shows that control of water transport towards the anode is a determining factor to increase air-breathing mPEMFC performances. An analytical 1D model is developed to capture the water transport and water content profile in the membrane. It shows that drying at the anode and flooding at the cathode can happen simultaneously, mainly due to dominant electro-osmotic drag at low cell temperatures. Experimental results demonstrate that injecting water at the anode, at a rate of 3 times the amount produced at the cathode, increases the cell performances at high current densities. By this method, the limiting current and maximum power densities have been raised by 100% and 30% respectively.

  14. Real-Time Cell-Electronic Sensing of Coal Fly Ash Particulate Matter for Toxicity-Based Air Quality Monitoring.

    PubMed

    Moe, Birget; Yuan, Chungang; Li, Jinhua; Du, Haiying; Gabos, Stephan; Le, X Chris; Li, Xing-Fang

    2016-06-20

    The development of a unique bioassay for cytotoxicity analysis of coal fly ash (CFA) particulate matter (PM) and its potential application for air quality monitoring is described. Using human cell lines, A549 and SK-MES-1, as live probes on microelectrode-embedded 96-well sensors, impedance changes over time are measured as cells are treated with varying concentrations (1 μg/mL-20 mg/mL) of CFA samples. A dose-dependent impedance change is determined for each CFA sample, from which an IC50 histogram is obtained. The assay was successfully applied to examine CFA samples collected from three coal-fired power plants (CFPs) in China. The samples were separated into three size fractions: PM2.5 (<2.5 μm), PM10-2.5 (2.5 μm < x < 10 μm), and PM10 (>10 μm). Dynamic cell-response profiles and temporal IC50 histograms of all samples show that CFA cytotoxicity depends on concentration, exposure time (0-60 h), and cell-type (SK-MES-1 > A549). The IC50 values differentiate the cytotoxicity of CFA samples based on size fraction (PM2.5 ≈ PM10-2.5 ≫ PM10) and the sampling location (CFP2 > CFP1 ≈ CFP3). Differential cytotoxicity measurements of particulates in human cell lines using cell-electronic sensing provide a useful tool for toxicity-based air quality monitoring and risk assessment. PMID:27124590

  15. Air support facilities. [interface between air and surface transportation systems

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Airports are discussed in terms of the interface between the ground and air for transportation systems. The classification systems, design, facilities, administration, and operations of airports are described.

  16. 78 FR 2711 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-14

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification,...

  17. 77 FR 56698 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-13

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification,...

  18. 77 FR 2603 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-18

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification,...

  19. 76 FR 59481 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-26

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification,...

  20. 77 FR 27835 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-11

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification,...

  1. 78 FR 66098 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... that a meeting of the Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for...

  2. 75 FR 22892 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-30

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification,...

  3. 75 FR 63255 - Air Traffic Procedures Advisory Committee Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-14

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee Meeting AGENCY: Federal Aviation... Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification,...

  4. 76 FR 27168 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-10

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC) will be held to review present air traffic control procedures and practices for standardization, revision, clarification,...

  5. 75 FR 68022 - Air Traffic Procedures Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-04

    ... Federal Aviation Administration Air Traffic Procedures Advisory Committee AGENCY: Federal Aviation... been issued for the Federal Aviation Administration Air Traffic Procedures Advisory Committee (ATPAC... Washington, DC, on October 29, 2010. Elizabeth Ray, Executive Director, Air Traffic Procedures...

  6. Comparison of safety and immunogenicity of a Vi polysaccharide typhoid vaccine with a whole-cell killed vaccine in Malaysian Air Force recruits.

    PubMed Central

    Panchanathan, V.; Kumar, S.; Yeap, W.; Devi, S.; Ismail, R.; Sarijan, S.; Sam, S. M.; Jusoh, Z.; Nordin, S.; Leboulleux, D.; Pang, T.

    2001-01-01

    OBJECTIVE: To carry out a comparative study of the safety and immunogenicity of Vi polysaccharide vaccine against whole-cell killed (WCK) typhoid vaccine. METHODS: The study was carried out on young adult recruits (aged 18-25 years) of the Malaysian Air Force. A total of 125 subjects received the Vi polysaccharide vaccine and 114 received the WCK vaccine. FINDINGS: The Vi vaccine was significantly less reactogenic than the WCK vaccine with regard to systemic and local reactions. Following administration of the Vi vaccine, seroconversion rates (defined as the percentage of subjects with a 4-fold rise of baseline antibody level) of 75.5% and 67% were observed at 2 weeks and 6 weeks, respectively, after immunization, compared with 25% and 31.3% among recipients of the WCK vaccine. Of the 110 Vi vaccinees with serological data, 21 (19%) had high, seroprotective, pre-immunization levels of anti-Vi antibodies (> or = 1 microgram/ml). The majority of subjects in this group came from a region in Malaysia which is known to have high typhoid endemicity. Interestingly, these antibody levels were boosted considerably following administration of vaccine at a level that was 5-fold higher than in subjects with low pre-immunization levels. In contrast, the seroconversion rates in those receiving the Vi vaccine were higher in subjects with low pre-immunization levels of anti-Vi antibodies (76-84%), compared to those with protective levels of > or = 1 microgram/ml prior to immunization (48-57%). CONCLUSIONS: The study reaffirms the safety and efficacy of the Vi polysaccharide vaccine and identifies a hitherto unrecognized advantage in its use, i.e. it is a potent immunogen that boosted considerably the protective antibody levels among a significant number of immunologically sensitized individuals living in typhoid-endemic regions. PMID:11584728

  7. [Morpho-functional reaction of spleen natural killer cells and macrophages to melatonin administration to the animals kept on different illumination regimens].

    PubMed

    Shatskikh, O A; Luzikova, E M

    2012-01-01

    The aim this investigation was to study the changes in the numbers of spleen CD57+ and CD68+ cells (natural killer cells and macrophages respectively) after melatonin administration to the animals kept on different illumination regimens. The experimental animals were given melatonin in dose of 0.03 mg per day for 2 and 4 weeks under conditions of natural illumination or artificial darkening. Spleen paraffin sections were stained using immunohistochemical methods for detection of CD57+ and CD68+ cells. It was shown that long-term administration of melatonin under conditions of natural illumination had an immunosuppressive effect, that was manifested by the depopulation of the marginal zones, white pulp and all the zones of the red pulp, parenchyma loosening and denudation of the reticular stroma of the organ. However, long-term hormone administration under conditions of artificial darkening had an immunostimulatory effect as evidenced by the increased inflow of immunocompetent cells into the spleen, their migration from the white pulp into the marginal zones and emigration into peripheral blood flow, concomitant with the increase in the number of lymphoid nodules. The number of CD57+ and CD68+ cells was increased in splenic periarterial lymphoid sheaths and decreased in B-dependent zones of the organ.

  8. Enhanced Ultraviolet Stability of Air-Processed Polymer Solar Cells by Al Doping of the ZnO Interlayer.

    PubMed

    Prosa, Mario; Tessarolo, Marta; Bolognesi, Margherita; Margeat, Olivier; Gedefaw, Desta; Gaceur, Meriem; Videlot-Ackermann, Christine; Andersson, Mats R; Muccini, Michele; Seri, Mirko; Ackermann, Jörg

    2016-01-27

    Photostability of organic photovoltaic devices represents a key requirement for the commercialization of this technology. In this field, ZnO is one of the most attractive materials employed as an electron transport layer, and the investigation of its photostability is of particular interest. Indeed, oxygen is known to chemisorb on ZnO and can be released upon UV illumination. Therefore, a deep analysis of the UV/oxygen effects on working devices is relevant for the industrial production where the coating processes take place in air and oxygen/ZnO contact cannot be avoided. Here we investigate the light-soaking stability of inverted organic solar cells in which four different solution-processed ZnO-based nanoparticles were used as electron transport layers: (i) pristine ZnO, (ii) 0.03 at %, (iii) 0.37 at %, and (iv) 0.8 at % aluminum-doped AZO nanoparticles. The degradation of solar cells under prolonged illumination (40 h under 1 sun), in which the ZnO/AZO layers were processed in air or inert atmosphere, is studied. We demonstrate that the presence of oxygen during the ZnO/AZO processing is crucial for the photostability of the resulting solar cell. While devices based on undoped ZnO were particularly affected by degradation, we found that using AZO nanoparticles the losses in performance, due to the presence of oxygen, were partially or totally prevented depending on the Al doping level.

  9. Computational modeling of air-breathing microfluidic fuel cells with flow-over and flow-through anodes

    NASA Astrophysics Data System (ADS)

    Zhang, Biao; Ye, Ding-ding; Sui, Pang-Chieh; Djilali, Ned; Zhu, Xun

    2014-08-01

    A three-dimensional computational model for air-breathing microfluidic fuel cells (AMFCs) with flow-over and flow-through anodes is developed. The coupled multiphysics phenomena of fluid flow, species transport and electrochemical reactions are resolved numerically. The model has been validated against experimental data using an in-house AMFC prototype with a flow-through anode. Characteristics of fuel transfer and fuel crossover for both types of anodes are investigated. The model results reveal that the fuel transport to the flow-over anode is intrinsically limited by the fuel concentration boundary layer. Conversely, fuel transport for the flow-through anode is convectively enhanced by the permeate flow, and no concentration boundary layer is observed. An unexpected additional advantage of the flow-through anode configuration is lower parasitic (crossover) current density than the flow-over case at practical low flow rates. Cell performance of the flow-through case is found to be limited by reaction kinetics. The present model provides insights into the fuel transport and fuel crossover in air-breathing microfluidic fuel cells and provides guidance for further design and operation optimization.

  10. High cell density cultivation of Pseudomonas putida KT2440 using glucose without the need for oxygen enriched air supply.

    PubMed

    Davis, Reeta; Duane, Gearoid; Kenny, Shane T; Cerrone, Federico; Guzik, Maciej W; Babu, Ramesh P; Casey, Eoin; O'Connor, Kevin E

    2015-04-01

    High Cell Density (HCD) cultivation of bacteria is essential for the majority of industrial processes to achieve high volumetric productivity (g L(-1) h(-1) ) of a bioproduct of interest. This study developed a fed batch bioprocess using glucose as sole carbon and energy source for the HCD of the well described biocatalyst Pseudomonas putida KT2440 without the supply of oxygen enriched air. Growth kinetics data from batch fermentations were used for building a bioprocess model and designing feeding strategies. An exponential followed by linearly increasing feeding strategy of glucose was found to be effective in maintaining biomass productivity while also delaying the onset of dissolved oxygen (supplied via compressed air) limitation. A final cell dry weight (CDW) of 102 g L(-1) was achieved in 33 h with a biomass productivity of 3.1 g L(-1) h(-1) which are the highest ever reported values for P. putida strains using glucose without the supply of pure oxygen or oxygen enriched air. The usefulness of the biomass as a biocatalyst was demonstrated through the production of the biodegradable polymer polyhydroxyalkanoate (PHA). When nonanoic acid (NA) was supplied to the glucose grown cells of P. putida KT2440, it accumulated 32% of CDW as PHA in 11 h (2.85 g L(-1) h(-1) ) resulting in a total of 0.56 kg of PHA in 18 L with a yield of 0.56 g PHA g NA(-1) .

  11. Preservation of immune effector cell function following administration of a dose-intense 5-fluorouracil-chemotherapy regimen.

    PubMed

    Weiner, L M; Hudes, G R; Kitson, J; Walczak, J; Watts, P; Litwin, S; O'Dwyer, P J

    1993-01-01

    In a phase II clinical trial of 5-fluorouracil (5FU) plus N-(phosphonacetyl)-L-aspartate (PALA) therapy administration, a number of slowly developing clinical responses were observed. Because of this, a variety of immune parameters were sequentially studied in 21 patients on this trial. Of the 21 patients studied, 20 provided sufficient samples to compare baseline with subsequent values, 10 of the 20 patients responded to treatment. Responders and non-responders did not differ in any studied parameter at baseline. After 2 months of therapy, non-specific monocyte cytotoxicity (NSMC), antibody-dependent monocyte cytotoxicity (ADMC) and natural killer (NK) activity were higher in the entire study population, but these increases were not statistically significant. When responders and non-responders were evaluated separately, it was apparent that the trend was due solely to the changes observed in the responding patient population. When mean lysis values for each patient group were determined for each studied time point, it was possible to generate a mean area under the cytotoxicity/time curve (AUC) for each studied parameter. NSMC and ADMC did not differ in responders and non-responders. However, NK activity was significantly greater by mean AUC analysis (P = 0.006) in the responding group; NK activity was maintained in the responders, but decreased in non-responders. When lymphocyte and monocyte expression of the surface markers beta 2-microglobulin, HLA-DR, CD56, HNK-1, CD16 and interleukin-2 receptor were evaluated, there were no differences among responders and non-responders at baseline by mean AUC analysis or when comparing baseline with non-baseline values. It is concluded that although baseline immunological characteristics do not identify patients who are likely to respond to weekly 5FU and PALA, treatment is not associated with deleterious effects on the immune effector function parameters evaluated in this study, there being no effects on expression of a

  12. Administrative Synergy

    ERIC Educational Resources Information Center

    Hewitt, Kimberly Kappler; Weckstein, Daniel K.

    2012-01-01

    One of the biggest obstacles to overcome in creating and sustaining an administrative professional learning community (PLC) is time. Administrators are constantly deluged by the tyranny of the urgent. It is a Herculean task to carve out time for PLCs, but it is imperative to do so. In this article, the authors describe how an administrative PLC…

  13. 76 FR 13851 - National Emission Standards for Hazardous Air Pollutants: Mercury Emissions From Mercury Cell...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-14

    ... 19, 2003, EPA promulgated the 2003 Mercury Cell NESHAP (40 CFR part 63, subpart IIIII, 68 FR 70904... final 2003 Mercury Cell NESHAP (68 FR 70905), we divided the chlorine production source category into... rely upon mercury cells for chlorine production. In December 2003 (68 FR 70949), we issued our...

  14. Newly recruited CD11b+, GR-1+, Ly6C(high) myeloid cells augment tumor-associated immunosuppression immediately following the therapeutic administration of oncolytic reovirus.

    PubMed

    Clements, Derek R; Sterea, Andra M; Kim, Youra; Helson, Erin; Dean, Cheryl A; Nunokawa, Anna; Coyle, Krysta Mila; Sharif, Tanveer; Marcato, Paola; Gujar, Shashi A; Lee, Patrick W K

    2015-05-01

    Tumor-associated immunosuppression aids cancer cells to escape immune-mediated attack and subsequent elimination. Recently, however, many oncolytic viruses, including reovirus, have been reported to overturn such immunosuppression and promote the development of a clinically desired antitumor immunity, which is known to promote favorable patient outcomes. Contrary to this existing paradigm, in this article we demonstrate that reovirus augments tumor-associated immunosuppression immediately following its therapeutic administration. Our data show that reovirus induces preferential differentiation of highly suppressive CD11b(+), Gr-1(+), Ly6C(high) myeloid cells from bone marrow hematopoietic progenitor cells. Furthermore, reovirus administration in tumor-bearing hosts drives time-dependent recruitment of CD11b(+), Gr-1(+), Ly6C(high) myeloid cells in the tumor milieu, which is further supported by virus-induced increased expression of numerous immune factors involved in myeloid-derived suppressor cell survival and trafficking. Most importantly, CD11b(+), Gr-1(+), Ly6C(high) myeloid cells specifically potentiate the suppression of T cell proliferation and are associated with the absence of IFN-γ response in the tumor microenvironment early during oncotherapy. Considering that the qualitative traits of a specific antitumor immunity are largely dictated by the immunological events that precede its development, our findings are of critical importance and must be considered while devising complementary interventions aimed at promoting the optimum efficacy of oncolytic virus-based anticancer immunotherapies. PMID:25825443

  15. Effects of the oral administration of viable and heat-killed Streptococcus bovis HC5 cells to pre-sensitized BALB/c mice.

    PubMed

    Paiva, Aline D; Fernandes, Kenner M; Dias, Roberto S; Rocha, Alípio S; de Oliveira, Leandro L; Neves, Clóvis A; de Paula, Sérgio O; Mantovani, Hilário C

    2012-01-01

    Antimicrobial peptides have been suggested as an alternative to classical antibiotics in livestock production and bacteriocin-producing bacteria could be added to animal feeds to deliver bacteriocins in the gastrointestinal (GI) tract of ruminant and monogastric animals. In this study, viable (V) and heat-killed (HK) Streptococcus bovis HC5 cells were orally administered to pre-sensitized mice in order to assess the effects of a bacteriocin-producing bacteria on histological parameters and the immune response of the GI tract of monogastric animals. The administration of V and HK S. bovis HC5 cells during 58 days to BALB/c mice did not affect weight gain, but an increase in gut permeability was detected in animals receiving the HK cells. Viable and heat killed cells caused similar morphological alterations in the GI tract of the animals, but the most prominent effects were detected in the small intestine. The oral administration of S. bovis HC5 also influenced cytokine production in the small intestine, and the immune-mediated activity differed between V and HK cells. The relative expression of IL-12 and INF-γ was significantly higher in the small intestine of mice treated with V cells, while an increase in IL-5, IL-13 and TNF-α expression was only detected in mice treated with HK cells. Considering that even under a condition of severe challenge (pre-sensitization followed by daily exposure to the same bacterial immunogen) the general health of the animals was maintained, it appears that oral administration of S. bovis HC5 cells could be a useful route to deliver bacteriocin in the GI tract of livestock animals.

  16. Effects of the Oral Administration of Viable and Heat-Killed Streptococcus bovis HC5 Cells to Pre-Sensitized BALB/c Mice

    PubMed Central

    Paiva, Aline D.; Fernandes, Kenner M.; Dias, Roberto S.; Rocha, Alípio S.; de Oliveira, Leandro L.; Neves, Clóvis A.; de Paula, Sérgio O.; Mantovani, Hilário C.

    2012-01-01

    Antimicrobial peptides have been suggested as an alternative to classical antibiotics in livestock production and bacteriocin-producing bacteria could be added to animal feeds to deliver bacteriocins in the gastrointestinal (GI) tract of ruminant and monogastric animals. In this study, viable (V) and heat-killed (HK) Streptococcus bovis HC5 cells were orally administered to pre-sensitized mice in order to assess the effects of a bacteriocin-producing bacteria on histological parameters and the immune response of the GI tract of monogastric animals. The administration of V and HK S. bovis HC5 cells during 58 days to BALB/c mice did not affect weight gain, but an increase in gut permeability was detected in animals receiving the HK cells. Viable and heat killed cells caused similar morphological alterations in the GI tract of the animals, but the most prominent effects were detected in the small intestine. The oral administration of S. bovis HC5 also influenced cytokine production in the small intestine, and the immune-mediated activity differed between V and HK cells. The relative expression of IL-12 and INF-γ was significantly higher in the small intestine of mice treated with V cells, while an increase in IL-5, IL-13 and TNF-α expression was only detected in mice treated with HK cells. Considering that even under a condition of severe challenge (pre-sensitization followed by daily exposure to the same bacterial immunogen) the general health of the animals was maintained, it appears that oral administration of S. bovis HC5 cells could be a useful route to deliver bacteriocin in the GI tract of livestock animals. PMID:23144752

  17. Ciprofloxacin Is Actively Transported across Bronchial Lung Epithelial Cells Using a Calu-3 Air Interface Cell Model

    PubMed Central

    Ong, Hui Xin; Traini, Daniela; Bebawy, Mary

    2013-01-01

    Ciprofloxacin is a well-established broad-spectrum fluoroquinolone antibiotic that penetrates well into the lung tissues; still, the mechanisms of its transepithelial transport are unknown. The contributions of specific transporters, including multidrug efflux transporters, organic cation transporters, and organic anion-transporting polypeptide transporters, to the uptake of ciprofloxacin were investigated in vitro using an air interface bronchial epithelial model. Our results demonstrate that ciprofloxacin is subject to predominantly active influx and a slight efflux component. PMID:23507281

  18. Accelerated OH(-) transport in activated carbon air cathode by modification of quaternary ammonium for microbial fuel cells.

    PubMed

    Wang, Xin; Feng, Cuijuan; Ding, Ning; Zhang, Qingrui; Li, Nan; Li, Xiaojing; Zhang, Yueyong; Zhou, Qixing

    2014-04-01

    Activated carbon (AC) is a promising catalyst for the air cathode of microbial fuel cells (MFCs) because of its high performance and low cost. To increase the performance of AC air cathodes, the acceleration of OH(-) transport is one of the most important methods, but it has not been widely investigated. Here we added quaternary ammonium to ACs by in situ anchoring of a quaternary ammonium/epoxide-reacting compound (QAE) or ex situ mixing with anion exchange resins in order to modify ACs from not only the external surface but also inside the pores. In 50 mM phosphate buffer solution (PBS), the in situ anchoring of QAE was a more effective way to increase the power. The highest power density of 2781 ± 36 mW/m(2), which is 10% higher than that of the control, was obtained using QAE-anchored AC cathodes. When the medium was switched to an unbuffered NaCl solution, the increase in maximum power density (885 ± 25 mW/m(2)) was in accordance with the anion exchange capacity (0.219 mmol/g). The highest power density of the anion exchange resin-mixed air cathode was 51% higher than that of the control, indicating that anion exchange is urgently needed in real wastewaters. Excess anchoring of QAE blocked both the mesopores and micropores, causing the power output to be inhibited.

  19. The GaAs solar cell research and development programs of the Air Force

    NASA Technical Reports Server (NTRS)

    Masloski, K. T.

    1980-01-01

    The compound GaAs is of interest for space application photovoltaics due to its inherent advantages over silicon. Higher efficiencies, superior radiation hardness, and a greater temperature resistance are the major advantages of GaAs over Si. Air Force programs look for ways of maximizing these advantages while minimizing disadvantages such as higher costs and weights. Four programs in GaAs photovoltaics are described and each program is discussed in terms of its objective, approach and status.

  20. Co-administration of vaccination with DNA encoding T cell epitope on the Der p and BCG inhibited airway remodeling in a murine model of chronic asthma.

    PubMed

    Kim, Chi Hong; Ahn, Joong Hyun; Kim, Seung Joon; Lee, Sook-Young; Kim, Young Kyoon; Kim, Kwan Hyoung; Moon, Hwa Sik; Song, Jeong Sup; Park, Sung Hak; Kwon, Soon Seog

    2006-01-01

    Therapeutic modalities of airway remodeling in asthma have proved to be unsuccessful regarding reversing the previously established chronic airway changes. Recently, the potential of plasmid DNA to inhibit the Th2 immune response has been demonstrated in animal models of asthma. Bacillus Calmette-Guerin (BCG) immunization also induced immunomodulation, which appeared to be reliant on the properties of the interferon-gamma that was produced. Mice were immunized with house dust mite extract (HDM). At the 3 week point, we injected BCG subcutaneously into mice on three successive weeks. One week after the BCG injection, we immunized mice with the DNA plasmid encoding for murine T-cell epitope on Dermatophagoide pteronyssinus 2 thrice weekly. At 9 weeks after immunization, we measured airway responsiveness. Twenty four hours later, we performed bronchoalveolar lavage and histological examinations. Co-administration of DNA vaccination and BCG resulted in a partial suppression of the overproduction of goblet cells and the thickness of the peribronchial smooth muscle in ongoing allergic responses. In the bronchoalveolar lavage fluid, the number of total cells and eosinophils was reduced, and regarding the change of cytokines, the concentration of IL-4 was also decreased, but interferon-gamma was increased in the co-administration group, opposed to the asthma group. These results suggest that co-administration of vaccination with the DNA encoding T-cell epitope and BCG are effective regarding ongoing allergic response and might constitute an ideal method for combating allergic disease in the future.

  1. Effect of Periodic Granulocyte Colony-Stimulating Factor Administration on Endothelial Progenitor Cells and Different Monocyte Subsets in Pediatric Patients with Muscular Dystrophies

    PubMed Central

    Sienkiewicz, Dorota; Grubczak, Kamil; Okurowska-Zawada, Bożena; Paszko-Patej, Grażyna; Miklasz, Paula; Singh, Paulina; Radzikowska, Urszula; Kulak, Wojciech

    2016-01-01

    Muscular dystrophies (MD) are heterogeneous group of diseases characterized by progressive muscle dysfunction. There is a large body of evidence indicating that angiogenesis is impaired in muscles of MD patients. Therefore, induction of dystrophic muscle revascularization should become a novel approach aimed at diminishing the extent of myocyte damage. Recently, we and others demonstrated that administration of granulocyte colony-stimulating factor (G-CSF) resulted in clinical improvement of patients with neuromuscular disorders. To date, however, the exact mechanisms underlying these beneficial effects of G-CSF have not been fully understood. Here we used flow cytometry to quantitate numbers of CD34+ cells, endothelial progenitor cells, and different monocyte subsets in peripheral blood of pediatric MD patients treated with repetitive courses of G-CSF administration. We showed that repetitive cycles of G-CSF administration induced efficient mobilization of above-mentioned cells including cells with proangiogenic potential. These findings contribute to better understanding the beneficial clinical effects of G-CSF in pediatric MD patients. PMID:26770204

  2. Convergence of air pollutant-induced redox-sensitive signals in the dendritic cells contributes to asthma pathogenesis.

    PubMed

    Li, Ning; Buglak, Nicholas

    2015-08-19

    Exposure to airborne particulate matter (PM) is a major risk factor for allergic airway inflammation such as asthma. Many of the PM components (i.e., polycyclic aromatic hydrocarbons and metals) are redox-active and capable of inducing cellular oxidative stress and injuries including inflammation and cell death. Airway epithelial cells and antigen-presenting dendritic cells (DC) are the major and direct targets of inhaled PM. The epithelial cells can further enhance the DC response to allergen and PM through several immune regulatory cytokines including thymic stromal lymphopoietin (TSLP), IL-33, and IL-25. Among these cytokines TSLP is particularly relevant to the mechanisms by which particulate air pollutants contribute to asthma pathogenesis. Studies have found that TSLP released by PM-exposed human airway epithelial cells could polarize the DC towards a T-helper 2 immune response, which is one of the key immunological mechanisms in asthma pathogenesis. The convergence of regulatory signals generated by PM-induced oxidative stress in DC and the interactions among them may be one of the major mechanisms that are specifically related to the contribution of PM towards asthma pathogenesis.

  3. Repeated administrations of human umbilical cord blood cells improve disease outcomes in a mouse model of Sanfilippo syndrome type III B.

    PubMed

    Willing, Alison E; Garbuzova-Davis, Svitlana N; Zayko, Olga; Derasari, Hiranya M; Rawls, Ashley E; James, Chris R; Mervis, Ron F; Sanberg, Cyndy D; Kuzmin-Nichols, Nicole; Sanberg, Paul R

    2014-01-01

    Sanfilippo syndrome type III B (MPS III B) is an inherited disorder characterized by a deficiency of α-N-acetylglucosaminidase (Naglu) enzyme leading to accumulation of heparan sulfate in lysosomes and severe neurological deficits. We have previously shown that a single administration of human umbilical cord mononuclear cells (hUCB MNCs) into Naglu knockout mice decreased behavioral abnormalities and tissue pathology. In this study, we tested whether repeated doses of hUCB MNCs would be more beneficial than a single dose of cells. Naglu mice at 3 months of age were randomly assigned to either a Media-only group or one of three hUCB MNC treatment groups--single low dose (3 × 10(6) cells), single high dose (1.8 × 10(7) cells), or multiple doses (3 × 10(6) cells monthly for 6 months) delivered intravenously; cyclosporine was injected intraperitoneally to immune suppress the mice for the duration of the study. An additional control group of wild-type mice was also used. We measured anxiety in an open field test and cognition in an active avoidance test prior to treatment and then at monthly intervals for 6 months. hUCB MNCs restored normal anxiety-like behavior in these mice (p < 0.001). The repeated cell administrations also restored hippocampal cytoarchitecture, protected the dendritic tree, decreased GM3 ganglioside accumulation, and decreased microglial activation, particularly in the hippocampus and cortex. These data suggest that the neuroprotective effect of hUCB MNCs can be enhanced by repeated cell administrations. PMID:25565636

  4. The Effect of Donor-Dependent Administration of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells following Focal Cerebral Ischemia in Rats.

    PubMed

    Park, Hyung Woo; Chang, Jong Wook; Yang, Yoon Sun; Oh, Wonil; Hwang, Jae Ha; Kim, Dong Gyu; Paek, Sun Ha

    2015-12-01

    Stroke is an ischemic disease caused by clotted vessel-induced cell damage. It is characterized by high morbidity and mortality and is typically treated with a tissue plasminogen activator (tPA). However, this therapy is limited by temporal constraints. Recently, several studies have focused on cell therapy as an alternative treatment. Most researches have used fixed donor cell administration, and hence, the effect of donor-dependent cell administration is unknown. In this study, we administered 3 types of donor-derived human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) in the ischemic boundary zone of the ischemic stroke rat model. We then performed functional and pathological characterization using rotarod, the limb placement test, and immunofluorescent staining. We observed a significant decrease in neuron number, and notable stroke-like motor dysfunction, as assessed by the rotarod test (~40% decrease in time) and the limb placement test (4.5 point increase) in control rats with ischemic stroke. The neurobehavioral performance of the rats with ischemic stroke that were treated with hUCB-MSCs was significantly better than that of rats in the vehicle-injected control group. Regardless of which donor cells were used, hUCB-MSC transplantation resulted in an accumulation of neuronal progenitor cells, and angiogenic and tissue repair factors in the ischemic boundary zone. The neurogenic and angiogenic profiles of the 3 types of hUCB-MSCs were very similar. Our results suggest that intraparenchymal administration of hUCB-MSCs results in significant therapeutic effects in the ischemic brain regardless of the type of donor. PMID:26713083

  5. Solvent Engineering for Ambient-Air-Processed, Phase-Stable CsPbI3 in Perovskite Solar Cells.

    PubMed

    Luo, Paifeng; Xia, Wei; Zhou, Shengwen; Sun, Lin; Cheng, Jigui; Xu, Chenxi; Lu, Yingwei

    2016-09-15

    Inorganic CsPbI3 perovskite solar cells (PSCs) owning comparable photovoltaic performance and enhanced thermal stability compared to organic-inorganic hybrid perovskites have attracted enormous interest in the past year. However, it is still a challenge to stabilize the desired black α-CsPbI3 perovskites in ambient air for photovoltaic applications. Herein, sequential solvent engineering including the addition of hydroiodic acid (HI) and subsequent isopropanol (IPA) treatment for fabricating stable and working CsPbI3 PSCs is developed, and a novel low-temperature phase-transition route from new intermediate Cs4PbI6 to stable α-CsPbI3 is also released for the first time. As such, the as-prepared PSCs give a relatively high power conversion efficiency (PCE) of 4.13% (reverse scan), and the steady-state power output of 1.88% is confirmed for the selected cell with an initial PCE of 3.13%. To the best of our knowledge, this is the first demonstration of fabricating CsPbI3 inorganic PSCs under fully open-air conditions. PMID:27569604

  6. Experimental investigation of water droplet-air flow interaction in a non-reacting PEM fuel cell channel

    NASA Astrophysics Data System (ADS)

    Esposito, Angelo; Montello, Aaron D.; Guezennec, Yann G.; Pianese, Cesare

    It has been well documented that water production in PEM fuel cells occurs in discrete locations, resulting in the formation and growth of discrete droplets on the gas diffusion layer (GDL) surface within the gas flow channels (GFCs). This research uses a simulated fuel cell GFC with three transparent walls in conjunction with a high speed fluorescence photometry system to capture videos of dynamically deforming droplets. Such videos clearly show that the droplets undergo oscillatory deformation patterns. Although many authors have previously investigated the air flow induced droplet detachment, none of them have studied these oscillatory modes. The novelty of this work is to process and analyze the recorded videos to gather information on the droplets induced oscillation. Plots are formulated to indicate the dominant horizontal and vertical deformation frequency components over the range of sizes of droplets from formation to detachment. The system is also used to characterize droplet detachment size at a variety of channel air velocities. A simplified model to explain the droplet oscillation mechanism is provided as well.

  7. Growth of airway epithelial cells at an air-liquid interface changes both the response to particle exposure and iron homeostasis.

    EPA Science Inventory

    RATIONALE: We tested the hypothesis that 1) relative to submerged cells, airway epithelial cells grown at an air-liquid interface and allowed to differentiate would have an altered response to particle exposure and 2) that these differences would be associated with indices of iro...

  8. Growth of airway epithelial cells at an air-liquid interface changes both the response to particle exposure and iron homeostasis

    EPA Science Inventory

    We tested the hypothesis that 1) relative to submerged cells, airway epithelial cells grown at an air-liquid interface and allowed to differentiate would have an altered response to particle exposure and 2) that these differences would be associated with indices of iron homeostas...

  9. REGULATION OF CYTOKINE PRODUCTION IN HUMAN ALVEOLAR MACHROPHAGES AND AIRWAY EPITHELIAL CELLS IN RESPONSE TO AMBIENT AIR POLLUTION PARTICLES: FURTHER MECHANISTIC STUDIES

    EPA Science Inventory

    In order to better understand how ambient air particulate matter (PM) affect lung health, the two main airway cell types likely to interact with inhaled particles, alveolar macrophages (AM) and airway epithelial cells have been exposed to particles in vitro and followed for endp...

  10. Requirement for natural killer cell-produced interferon gamma in defense against murine cytomegalovirus infection and enhancement of this defense pathway by interleukin 12 administration

    PubMed Central

    1995-01-01

    killing at levels comparable to those observed in control-treated mice. The consequences of interleukin 12 (IL-12) administration, a known potent inducer of IFN- gamma production by NK cells, were evaluated in MCMV-infected mice. Low IL-12 doses, i.e., 1 ng/d, increased NK cell cytotoxicity and IFN-gamma production up to twofold and resulted in improved antiviral status; virus-induced hepatitis was decreased as much as fivefold, and viral burdens were decreased to levels below detection.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:7561678

  11. Spatial and Temporal Effects of Free-Air CO2 Enrichment (POPFACE) on Leaf Growth, Cell Expansion, and Cell Production in a Closed Canopy of Poplar1

    PubMed Central

    Taylor, Gail; Tricker, Penny J.; Zhang, Fang Z.; Alston, Victoria J.; Miglietta, Franco; Kuzminsky, Elena

    2003-01-01

    Leaf expansion in the fast-growing tree, Populus × euramericana was stimulated by elevated [CO2] in a closed-canopy forest plantation, exposed using a free air CO2 enrichment technique enabling long-term experimentation in field conditions. The effects of elevated [CO2] over time were characterized and related to the leaf plastochron index (LPI), and showed that leaf expansion was stimulated at very early (LPI, 0–3) and late (LPI, 6–8) stages in development. Early and late effects of elevated [CO2] were largely the result of increased cell expansion and increased cell production, respectively. Spatial effects of elevated [CO2] were also marked and increased final leaf size resulted from an effect on leaf area, but not leaf length, demonstrating changed leaf shape in response to [CO2]. Leaves exhibited a basipetal gradient of leaf development, investigated by defining seven interveinal areas, with growth ceasing first at the leaf tip. Interestingly, and in contrast to other reports, no spatial differences in epidermal cell size were apparent across the lamina, whereas a clear basipetal gradient in cell production rate was found. These data suggest that the rate and timing of cell production was more important in determining leaf shape, given the constant cell size across the leaf lamina. The effect of elevated [CO2] imposed on this developmental gradient suggested that leaf cell production continued longer in elevated [CO2] and that basal increases in cell production rate were also more important than altered cell expansion for increased final leaf size and altered leaf shape in elevated [CO2]. PMID:12529526

  12. How often should a red blood cell administration set be changed while a patient is being transfused? A commentary and review of the literature.

    PubMed

    Blest, A; Roberts, M; Murdock, J; Watson, D; Brunskill, S

    2008-04-01

    Current recommendations vary with regard to the frequency of change of a red blood cell (RBC) administration set. A full review was undertaken to evaluate the recommendations for how often a RBC administration set should be changed while a patient is being transfused. Comprehensive searches of Medline, Embase, Cinahl, the Cochrane Library, handsearching of transfusion journals, guidelines and websites and contact with administration set manufacturers identified 32 relevant papers: 11 clinical updates; 11 guidelines; 5 manufacturer data sheets; 3 standards; 1 Department of Health report and 1 expert opinion. Recommendations varied widely across papers. There was no pattern in recommendation by paper type, date or country of origin. Recommendations were based on change of RBC administration set either after a given number of hours or number of RBC units. The recommendations varied widely and ranged from 4 to 48 h and from 'every unit' to 'several units'. The most frequent recommendations were change of RBC administration set after 12 h or 4 units. Methodological quality of the included papers is poor. There is no formal evidence base on which to support current recommendations or challenge the current British Committee for Standards in Haematology guideline. Targeted research aimed at establishing an evidence base may be warranted and would need to document other variables that can impact frequency of change, including type of filter, age of blood and duration of RBC transfusion. PMID:18399846

  13. Effects of air pollution-related heavy metals on the viability and inflammatory responses of human airway epithelial cells.

    PubMed

    Honda, Akiko; Tsuji, Kenshi; Matsuda, Yugo; Hayashi, Tomohiro; Fukushima, Wataru; Sawahara, Takahiro; Kudo, Hitomi; Murayama, Rumiko; Takano, Hirohisa

    2015-01-01

    Various metals produced from human activity are ubiquitously detected in ambient air. The metals may lead to induction and/or exacerbation of respiratory diseases, but the significant metals and factors contributing to such diseases have not been identified. To compare the effects of each metal and different oxidation states of metals on human airway, we examined the viability and production of interleukin (IL)-6 and IL-8 using BEAS-2B cell line, derived from human airway epithelial cells. Airway epithelial cells were exposed to Mn(2+), V(4+), V(5+), Cr(3+), Cr(6+), Zn(2+), Ni(2+), and Pb(2+) at a concentration of 0.5, 5, 50, or 500 μmol/L for 24 hours. Mn and V decreased the cell viability in a concentration-dependent manner, and V(5+) tended to have a greater effect than V(4+). The Cr decreased the cell viability, and (Cr(+6)) at concentrations of 50 and 500 μmol/L was more toxic than (Cr(+3)). Zn at a concentration of 500 μmol/L greatly decreased the cell viability, whereas Ni at the same concentration increased it. Pb produced fewer changes. Mn and Ni at a concentration of 500 μmol/L induced the significant production of IL-6 and IL-8. However, most of the metals including (V(+4), V(+5)), (Cr(+3), Cr(+6)), Zn, and Pb inhibited the production of both IL-6 and IL-8. The present results indicate that various heavy metals have different effects on toxicity and the proinflammatory responses of airway epithelial cells, and those influences also depend on the oxidation states of the metals.

  14. Active water management at the cathode of a planar air-breathing polymer electrolyte membrane fuel cell using an electroosmotic pump

    NASA Astrophysics Data System (ADS)

    Fabian, T.; O'Hayre, R.; Litster, S.; Prinz, F. B.; Santiago, J. G.

    In a typical air-breathing fuel cell design, ambient air is supplied to the cathode by natural convection and dry hydrogen is supplied to a dead-ended anode. While this design is simple and attractive for portable low-power applications, the difficulty in implementing effective and robust water management presents disadvantages. In particular, excessive flooding of the open-cathode during long-term operation can lead to a dramatic reduction of fuel cell power. To overcome this limitation, we report here on a novel air-breathing fuel cell water management design based on a hydrophilic and electrically conductive wick in conjunction with an electroosmotic (EO) pump that actively pumps water out of the wick. Transient experiments demonstrate the ability of the EO-pump to "resuscitate" the fuel cell from catastrophic flooding events, while longer term galvanostatic measurements suggest that the design can completely eliminate cathode flooding using less than 2% of fuel cell power, and lead to stable operation with higher net power performance than a control design without EO-pump. This demonstrates that active EO-pump water management, which has previously only been demonstrated in forced-convection fuel cell systems, can also be applied effectively to miniaturized (<5 W) air-breathing fuel cell systems.

  15. An Air of Concern.

    ERIC Educational Resources Information Center

    Singer, Terry E.; Shonkwiler, Tonja; Birr, David

    1998-01-01

    Examines how indoor air quality (IAQ) problems can create difficulties for a school both administratively, and legally. Discusses how to identify the IAQ symptoms and the Occupational Safety and Health Administration's industry standards for IAQ, as well as tips for reducing liability risk. (GR)

  16. Detonation Nanodiamond Toxicity in Human Airway Epithelial Cells Is Modulated by Air Oxidation

    EPA Science Inventory

    Detonational nanodiamonds (DND), a nanomaterial with an increasing range of industrial and biomedical applications, have previously been shown to induce a pro-inflammatory response in cultured human airway epithelial cells (HAEC). We now show that surface modifications induced by...

  17. Mutagenicity, sister chromatid exchange inducibility and in vitro cell transforming ability of particulates from Athens air

    SciTech Connect

    Athanasiou, K.; Arzimanoglou, I.; Piccoli, C.; Yamasaki, H.

    1987-09-01

    Airborne particulates were collected over a period of twelve months by the use of Hi-Vol samplers in the basin of Athens, Greece. N-Hexane extracts were tested in a battery of in vitro tests for their ability to induce mutation in bacteria as well as mutations, sister chromatid exchange and morphological transformation in cultured mammalian cells. Positive results were found for mutagenicity with Salmonella strain TA98 in the Ames assay, for sister chromatid exchange induction in CHO cells and for transformation in BALB/c 3T3 cells in culture. They also showed weak non-dose-related induction of ouabain resistance in BALB/c 3T3 cells. The contribution of oxidizing and nitrating agents found in the Athens atmosphere, together with sunlight UV irradiation in the formation of direct acting mutagens and potential carcinogens from ambient polycyclic aromatic hydrocarbons, is suggested.

  18. Air Force/Ion Physics hardened lithium doped solar cell development

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A.; Bartels, F.; Carnes, C.; Ho, J.; Smith, D.

    1971-01-01

    Introduction of lithium by ion implantation eliminates reproducibility and surface problem deficiencies of other introduction techniques. Implantation has been demonstrated to make possible a degree of control over the cell lithium content which has not previously been available. Front barrier development remains to be completed. Successful development of the barrier will make available the freedom to select optimum lithium concentration throughout the cell, including in the vicinity of the junction.

  19. Effects of Female Sex Hormones on Susceptibility to HSV-2 in Vaginal Cells Grown in Air-Liquid Interface.

    PubMed

    Lee, Yung; Dizzell, Sara E; Leung, Vivian; Nazli, Aisha; Zahoor, Muhammad A; Fichorova, Raina N; Kaushic, Charu

    2016-01-01

    The lower female reproductive tract (FRT) is comprised of the cervix and vagina, surfaces that are continuously exposed to a variety of commensal and pathogenic organisms. Sexually transmitted viruses, such as herpes simplex virus type 2 (HSV-2), have to traverse the mucosal epithelial lining of the FRT to establish infection. The majority of current culture systems that model the host-pathogen interactions in the mucosal epithelium have limitations in simulating physiological conditions as they employ a liquid-liquid interface (LLI), in which both apical and basolateral surfaces are submerged in growth medium. We designed the current study to simulate in vivo conditions by growing an immortalized vaginal epithelial cell line (Vk2/E6E7) in culture with an air-liquid interface (ALI) and examined the effects of female sex hormones on their growth, differentiation, and susceptibility to HSV-2 under these conditions, in comparison to LLI cultures. ALI conditions induced Vk2/E6E7 cells to grow into multi-layered cultures compared to the monolayers present in LLI conditions. Vk2 cells in ALI showed higher production of cytokeratin in the presence of estradiol (E2), compared to cells grown in progesterone (P4). Cells grown under ALI conditions were exposed to HSV-2-green fluorescent protein (GFP) and the highest infection and replication was observed in the presence of P4. Altogether, this study suggests that ALI cultures more closely simulate the in vivo conditions of the FRT compared to the conventional LLI cultures. Furthermore, under these conditions P4 was found to confer higher susceptibility to HSV-2 infection in vaginal cells. The vaginal ALI culture system offers a better alternative to study host-pathogen interactions. PMID:27589787

  20. Effects of Female Sex Hormones on Susceptibility to HSV-2 in Vaginal Cells Grown in Air-Liquid Interface

    PubMed Central

    Lee, Yung; Dizzell, Sara E.; Leung, Vivian; Nazli, Aisha; Zahoor, Muhammad A.; Fichorova, Raina N.; Kaushic, Charu

    2016-01-01

    The lower female reproductive tract (FRT) is comprised of the cervix and vagina, surfaces that are continuously exposed to a variety of commensal and pathogenic organisms. Sexually transmitted viruses, such as herpes simplex virus type 2 (HSV-2), have to traverse the mucosal epithelial lining of the FRT to establish infection. The majority of current culture systems that model the host-pathogen interactions in the mucosal epithelium have limitations in simulating physiological conditions as they employ a liquid-liquid interface (LLI), in which both apical and basolateral surfaces are submerged in growth medium. We designed the current study to simulate in vivo conditions by growing an immortalized vaginal epithelial cell line (Vk2/E6E7) in culture with an air-liquid interface (ALI) and examined the effects of female sex hormones on their growth, differentiation, and susceptibility to HSV-2 under these conditions, in comparison to LLI cultures. ALI conditions induced Vk2/E6E7 cells to grow into multi-layered cultures compared to the monolayers present in LLI conditions. Vk2 cells in ALI showed higher production of cytokeratin in the presence of estradiol (E2), compared to cells grown in progesterone (P4). Cells grown under ALI conditions were exposed to HSV-2-green fluorescent protein (GFP) and the highest infection and replication was observed in the presence of P4. Altogether, this study suggests that ALI cultures more closely simulate the in vivo conditions of the FRT compared to the conventional LLI cultures. Furthermore, under these conditions P4 was found to confer higher susceptibility to HSV-2 infection in vaginal cells. The vaginal ALI culture system offers a better alternative to study host-pathogen interactions. PMID:27589787

  1. Air-Independent Solid Oxide Fuel Cells for NASA's LOX-CH4 Landers

    NASA Technical Reports Server (NTRS)

    Ryan, Abigail C.; Araghi, Koorosh R.; Farmer, Serene C.

    2013-01-01

    Gemini, Apollo, and Space Shuttle used fuel cells as main power source for vehicle and water source for life support and thermal PEM (Gemini) and Alkaline (Apollo, Shuttle) fuel cells were used Ideal for short (less than 3 weeks) missions when the required O2 and H2 can be launched with the vehicle. New missions that might require long-duration stays in orbit or at a habitat, cannot rely on the availability of pure reactants but should also aim to be sun-independent - a problem for which Solid Oxide Fuel Cells might be the answer. Recently, NASA has investigated & developed LOX/CH4-propelled landers (Altair, MORPHEUS). In order to preserve mission flexibility, fuel cells are being studied as a potential power source. Much of NASA's fuel cell development has been focused on creating a dead-headed, non-flow through PEM fuel cells which would weigh less and be more reliable than the existing Alkaline and PEM technology; however, LOX/CH4 as a propellant introduces SOFCs as a power option due to their ability to accept those reactants without much reforming.

  2. Administrative Ecology

    ERIC Educational Resources Information Center

    McGarity, Augustus C., III; Maulding, Wanda

    2007-01-01

    This article discusses how all four facets of administrative ecology help dispel the claims about the "impossibility" of the superintendency. These are personal ecology, professional ecology, organizational ecology, and community ecology. Using today's superintendency as an administrative platform, current literature describes a preponderance of…

  3. Administrative Support.

    ERIC Educational Resources Information Center

    Doran, Dorothy; And Others

    This guide is intended to assist business education teachers in administrative support courses. The materials presented are based on the Arizona validated occupational competencies and tasks for the occupations of receptionist, secretary, and administrative assistant. Word processing skills have been infused into each of the three sections. The…

  4. Assessment of heat shock protein (HSP60, HSP72, HSP90, and HSC70) expression in cultured limbal stem cells following air lifting

    PubMed Central

    Mohammadi, Parvaneh; Daryadel, Arezoo; Baharvand, Hossein

    2010-01-01

    Objectives The aim of this study is to create an ex vivo model to examine the expression of major heat-shock protein (HSP) families; HSP60, HSP72, and HSP90, and heat-shock cognate 70 (HCS70) at the mRNA and protein level in differentiating corneal cells from limbal stem cells (LSC) following air exposure. Methods Limbal biopsies taken from cadaveric normal human limbus were cultivated as explants on human amniotic membrane (HAM) and plastic dish (PD). Corneal differentiation was induced by air lifting for 16 days. The expression of putative LSC markers (P63 and ATP-binding cassette G2 [ABCG2]), corneal markers (keratin 3 [K3/12] and connexin 43 [CX43]), and HSP60, HSP72, HSP90, and HSC70 were tested by RT–PCR, immunofluorescence, and flow cytometry pre- and post-air exposure. Fresh limbal and corneal tissues were used as control groups. Results Air lifting induced corneal differentiation with a decrease in the number of P63+ cells and an increase in the number of K3+/CX43+ cells, which characterized transient amplifying cells (TACs). Moreover, denuded HAM provided a superior niche for LSC proliferation and phenotype maintenance in vitro. Additionally, we have evidence that expressions of HSC70 as well as HSP72 were enhanced through corneal differentiation and HSP90 post-air lifting in vitro and in vivo. HSP60, however, was not detected in either LSC or corneal cells, in vivo and in vitro. Conclusions These results suggest that corneal differentiation following air exposure may regulate HSP72 and HSC70 expression. In addition, HSP72 and HSP90 may protect LSC and corneal cells against oxidative stress. PMID:20806039

  5. 14 CFR 93.32 - Administrative provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Administrative provisions. 93.32 Section 93.32 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES Congestion and Delay Reduction...

  6. Heme oxygenase-1 protects endothelial cells from the toxicity of air pollutant chemicals.

    PubMed

    Lawal, Akeem O; Zhang, Min; Dittmar, Michael; Lulla, Aaron; Araujo, Jesus A

    2015-05-01

    Diesel exhaust particles (DEPs) are a major component of diesel emissions, responsible for a large portion of their toxicity. In this study, we examined the toxic effects of DEPs on endothelial cells and the role of DEP-induced heme oxygenase-1 (HO-1) expression. Human microvascular endothelial cells (HMECs) were treated with an organic extract of DEPs from an automobile engine (A-DEP) or a forklift engine (F-DEP) for 1 and 4h. ROS generation, cell viability, lactate dehydrogenase leakage, expression of HO-1, inflammatory genes, cell adhesion molecules and unfolded protein respone (UPR) gene were assessed. HO-1 expression and/or activity were inhibited by siRNA or tin protoporphyrin (Sn PPIX) and enhanced by an expression plasmid or cobalt protoporphyrin (CoPPIX). Exposure to 25μg/ml of A-DEP and F-DEP significantly induced ROS production, cellular toxicity and greater levels of inflammatory and cellular adhesion molecules but to a different degree. Inhibition of HO-1 enzymatic activity with SnPPIX and silencing of the HO-1 gene by siRNA enhanced DEP-induced ROS production, further decreased cell viability and increased expression of inflammatory and cell adhesion molecules. On the other hand, overexpression of the HO-1 gene by a pcDNA 3.1D/V5-HO-1 plasmid significantly mitigated ROS production, increased cell survival and decreased the expression of inflammatory genes. HO-1 expression protected HMECs from DEP-induced prooxidative and proinflammatory effects. Modulation of HO-1 expression could potentially serve as a therapeutic target in an attempt to inhibit the cardiovascular effects of ambient PM.

  7. Population and single-cell genomics reveal the Aire dependency, relief from Polycomb silencing, and distribution of self-antigen expression in thymic epithelia

    PubMed Central

    Shikama-Dorn, Noriko; Zhanybekova, Saule; Nusspaumer, Gretel; Macaulay, Iain C.; Deadman, Mary E.; Heger, Andreas; Ponting, Chris P.; Holländer, Georg A.

    2014-01-01

    Promiscuous gene expression (PGE) by thymic epithelial cells (TEC) is essential for generating a diverse T cell antigen receptor repertoire tolerant to self-antigens, and thus for avoiding autoimmunity. Nevertheless, the extent and nature of this unusual expression program within TEC populations and single cells are unknown. Using deep transcriptome sequencing of carefully identified mouse TEC subpopulations, we discovered a program of PGE that is common between medullary (m) and cortical TEC, further elaborated in mTEC, and completed in mature mTEC expressing the autoimmune regulator gene (Aire). TEC populations are capable of expressing up to 19,293 protein-coding genes, the highest number of genes known to be expressed in any cell type. Remarkably, in mouse mTEC, Aire expression alone positively regulates 3980 tissue-restricted genes. Notably, the tissue specificities of these genes include known targets of autoimmunity in human AIRE deficiency. Led by the observation that genes induced by Aire expression are generally characterized by a repressive chromatin state in somatic tissues, we found these genes to be strongly associated with H3K27me3 marks in mTEC. Our findings are consistent with AIRE targeting and inducing the promiscuous expression of genes previously epigenetically silenced by Polycomb group proteins. Comparison of the transcriptomes of 174 single mTEC indicates that genes induced by Aire expression are transcribed stochastically at low cell frequency. Furthermore, when present, Aire expression-dependent transcript levels were 16-fold higher, on average, in individual TEC than in the mTEC population. PMID:25224068

  8. Population and single-cell genomics reveal the Aire dependency, relief from Polycomb silencing, and distribution of self-antigen expression in thymic epithelia.

    PubMed

    Sansom, Stephen N; Shikama-Dorn, Noriko; Zhanybekova, Saule; Nusspaumer, Gretel; Macaulay, Iain C; Deadman, Mary E; Heger, Andreas; Ponting, Chris P; Holländer, Georg A

    2014-12-01

    Promiscuous gene expression (PGE) by thymic epithelial cells (TEC) is essential for generating a diverse T cell antigen receptor repertoire tolerant to self-antigens, and thus for avoiding autoimmunity. Nevertheless, the extent and nature of this unusual expression program within TEC populations and single cells are unknown. Using deep transcriptome sequencing of carefully identified mouse TEC subpopulations, we discovered a program of PGE that is common between medullary (m) and cortical TEC, further elaborated in mTEC, and completed in mature mTEC expressing the autoimmune regulator gene (Aire). TEC populations are capable of expressing up to 19,293 protein-coding genes, the highest number of genes known to be expressed in any cell type. Remarkably, in mouse mTEC, Aire expression alone positively regulates 3980 tissue-restricted genes. Notably, the tissue specificities of these genes include known targets of autoimmunity in human AIRE deficiency. Led by the observation that genes induced by Aire expression are generally characterized by a repressive chromatin state in somatic tissues, we found these genes to be strongly associated with H3K27me3 marks in mTEC. Our findings are consistent with AIRE targeting and inducing the promiscuous expression of genes previously epigenetically silenced by Polycomb group proteins. Comparison of the transcriptomes of 174 single mTEC indicates that genes induced by Aire expression are transcribed stochastically at low cell frequency. Furthermore, when present, Aire expression-dependent transcript levels were 16-fold higher, on average, in individual TEC than in the mTEC population.

  9. A fractal time thermal model for predicting the surface temperature of air-cooled cylindrical Li-ion cells based on experimental measurements

    NASA Astrophysics Data System (ADS)

    Reyes-Marambio, Jorge; Moser, Francisco; Gana, Felipe; Severino, Bernardo; Calderón-Muñoz, Williams R.; Palma-Behnke, Rodrigo; Estevez, Pablo A.; Orchard, Marcos; Cortés, Marcelo

    2016-02-01

    This paper presents a experimentally-validated fractal time thermal model to describe the discharge and cooling down processes of air-cooled cylindrical Lithium-ion cells. Three cases were studied, a spatially isolated single cell under natural convection and two spatial configurations of modules with forced air cooling: staggered and aligned arrays with 30 and 25 cells respectively. Surface temperature measurements for discharge processes were obtained in a single cell at 1 C, 2 C and 3 C discharge rates, and in the two arrays at 1 C discharge rate. In the modules, surface temperature measurements were obtained for selected cells at specific inlet cooling air speeds. The fractal time energy equation captures the anomalous temperature relaxation and describes the cell surface temperature using a stretched exponential model. Stretched exponential temperature models of cell surface temperature show a better agreement with experimental measurements than pure exponential temperature models. Cells closer to the horizontal side walls have a better heat dissipation than the cells along the centerline of the module. The high prediction capabilities of the fractal time energy equation are useful in new design approaches of thermal control strategies of modules and packs, and to develop more efficient signal-correction algorithms in multipoint temperature measurement technologies in Li-ion batteries.

  10. Heme oxygenase-1 protects endothelial cells from the toxicity of air pollutant chemicals

    SciTech Connect

    Lawal, Akeem O.; Zhang, Min; Dittmar, Michael; Lulla, Aaron; Araujo, Jesus A.

    2015-05-01

    Diesel exhaust particles (DEPs) are a major component of diesel emissions, responsible for a large portion of their toxicity. In this study, we examined the toxic effects of DEPs on endothelial cells and the role of DEP-induced heme oxygenase-1 (HO-1) expression. Human microvascular endothelial cells (HMECs) were treated with an organic extract of DEPs from an automobile engine (A-DEP) or a forklift engine (F-DEP) for 1 and 4 h. ROS generation, cell viability, lactate dehydrogenase leakage, expression of HO-1, inflammatory genes, cell adhesion molecules and unfolded protein respone (UPR) gene were assessed. HO-1 expression and/or activity were inhibited by siRNA or tin protoporphyrin (Sn PPIX) and enhanced by an expression plasmid or cobalt protoporphyrin (CoPPIX). Exposure to 25 μg/ml of A-DEP and F-DEP significantly induced ROS production, cellular toxicity and greater levels of inflammatory and cellular adhesion molecules but to a different degree. Inhibition of HO-1 enzymatic activity with SnPPIX and silencing of the HO-1 gene by siRNA enhanced DEP-induced ROS production, further decreased cell viability and increased expression of inflammatory and cell adhesion molecules. On the other hand, overexpression of the HO-1 gene by a pcDNA 3.1D/V5-HO-1 plasmid significantly mitigated ROS production, increased cell survival and decreased the expression of inflammatory genes. HO-1 expression protected HMECs from DEP-induced prooxidative and proinflammatory effects. Modulation of HO-1 expression could potentially serve as a therapeutic target in an attempt to inhibit the cardiovascular effects of ambient PM. - Highlights: • We examined the role of HO-1 expression on diesel exhaust particle (DEP) in endothelial cells. • DEPs exert cytotoxic and inflammatory effects on human microvascular endothelial cells (HMECs). • DEPs induce HO-1 expression in HMECs. • HO-1 protects against the oxidative stress induced by DEps. • HO-1 attenuates the proinflammatory effects

  11. Effects of azide on electron transport of exoelectrogens in air-cathode microbial fuel cells.

    PubMed

    Zhou, Xiangtong; Qu, Youpeng; Kim, Byung Hong; Choo, Pamela Yengfung; Liu, Jia; Du, Yue; He, Weihua; Chang, In Seop; Ren, Nanqi; Feng, Yujie

    2014-10-01

    The effects of azide on electron transport of exoelectrogens were investigated using air-cathode MFCs. These MFCs enriched with azide at the concentration higher than 0.5mM generated lower current and coulomb efficiency (CE) than the control reactors, but at the concentration lower than 0.2mM MFCs generated higher current and CE. Power density curves showed overshoot at higher azide concentrations, with power and current density decreasing simultaneously. Electrochemical impedance spectroscopy (EIS) showed that azide at high concentration increased the charge transfer resistance. These analyses might reflect that a part of electrons were consumed by the anode microbial population rather than transferred to the anode. Bacterial population analyses showed azide-enriched anodes were dominated by Deltaproteobacteria compared with the controls. Based on these results it is hypothesized that azide can eliminate the growth of aerobic respiratory bacteria, and at the same time is used as an electron acceptor/sink.

  12. Development of a 10 kW hydrogen/air PEM fuel cell stack

    SciTech Connect

    Barbir, F.; Marken, F.; Bahar, B.; Kolde, J.A.

    1996-12-31

    PEM fuel cells have potential for meeting automotive industry`s power density and cost requirements, such as 0.8 kW/kg, 0.8 kW/1 and $30/kW. For automotive applications, the fuel cell power requirements are in the 10-100 kW range. As the first phase in reaching this power output, a 10 kW PEM fuel cell stack has been developed at Energy Partners. The stack consists of 50 cells with relatively large active area of 780 cm{sup 2}. The main feature of the stack is the advanced membrane electrode assembly (MEA) developed by W.L. Gore & Associates, Inc. These novel MEAs consist of a thin composite perfluorinated polymer membrane with a catalyst layer with platinum loading of 0.3 Mg/cm{sup 2} on each side. The combination of reinforcement and thinness provides high membrane conductance and improved water distribution in the operating cell. In addition, the membrane has excellent mechanical properties (particularly when it is hydrated) and dimensional stability.

  13. Spatial distribution of bacterial communities on volumetric and planar anodes in single-chamber air-cathode microbial fuel cells.

    PubMed

    Vargas, Ignacio T; Albert, Istvan U; Regan, John M

    2013-11-01

    Pyrosequencing was used to characterize bacterial communities in air-cathode microbial fuel cells across a volumetric (graphite fiber brush) and a planar (carbon cloth) anode, where different physical and chemical gradients would be expected associated with the distance between anode location and the air cathode. As expected, the stable operational voltage and the coulombic efficiency (CE) were higher for the volumetric anode than the planar anode (0.57 V and CE = 22% vs. 0.51 V and CE = 12%). The genus Geobacter was the only known exoelectrogen among the observed dominant groups, comprising 57 ± 4% of recovered sequences for the brush and 27 ± 5% for the carbon-cloth anode. While the bacterial communities differed between the two anode materials, results showed that Geobacter spp. and other dominant bacterial groups were homogenously distributed across both planar and volumetric anodes. This lends support to previous community analysis interpretations based on a single biofilm sampling location in these systems. PMID:23616357

  14. Hollow-spherical Co/N-C nanoparticle as an efficient electrocatalyst used in air cathode microbial fuel cell.

    PubMed

    Yang, Tingting; Li, Kexun; Pu, Liangtao; Liu, Ziqi; Ge, Baochao; Pan, Yajun; Liu, Ying

    2016-12-15

    The hollow-spherical Co/N-C nanoparticle, which is synthesized via a simple hydrothermal reaction followed by heat treatment, is firstly used as electrocatalyst for oxygen reduction reaction (ORR) in air-cathode microbial fuel cell (MFC). The maximum power density of MFC with 10% Co/N-C air-cathode is as high as 2514±59mWm(-2), which is almost 174% higher than the control. The exchange current density (i0) of cathode equipped with 10% Co/N-C is 238% higher than that of untreated AC. While the total resistance of treated samples decreases from 13.017 to 10.255Ω. The intensity ratio of Raman D to G band (ID/IG) decreases from 0.93 (N-C) to 0.73 (Co/N-C), indicating the catalyst forms graphite structure. Both XRD and XPS testify that Co is bonded to N within graphitic sheets and serves as the active sites in ORR. The four-electron pathway of the Co/N-C also plays a crucial role in electrochemical catalytic activity. As a result, it can be expected that the as-synthesized Co/N-C, with extraordinary electro-catalytic performance towards ORR, will be a promising alternative to the state-of-the-art non-precious metal ORR electro-catalysts for electrochemical energy applications.

  15. Temporal variations of cathode performance in air-cathode single-chamber microbial fuel cells with different separators

    NASA Astrophysics Data System (ADS)

    Ma, Jinxing; Wang, Zhiwei; Suor, Denis; Liu, Shumeng; Li, Jiaqi; Wu, Zhichao

    2014-12-01

    An ideal separator is essential for efficient power production from air-cathode single-chamber microbial fuel cells (MFCs). In this study, we use different kinds of membranes as separators, including Nafion 117 proton exchange membrane, polyethersulfone and poly(vinylidene fluoride) microfiltration membranes. Temporal variations of cathode performance are monitored during the experiment. Results show that MFCs with microfiltration membranes present higher power output but deterioration is still observed after about 600-h operation. With the utilization of appropriate separators (e.g., polyethersulfone membrane), biofouling, cation fouling and chemical scale fouling of the cathodes are alleviated while reaction fouling seems inevitable. Moreover, it is found that Coulombic efficiency (CE) and energy efficiency (EE) are also related to the cathode performance. Despite relatively high oxygen diffusivity (1.49 × 10-5 cm2 s-1), CE and EE of the MFC with 0.1 μm pore-size polyethersulfone membrane can reach 92.8% and 13.7%, respectively, when its average power density registers 403.5 mW m-2. This phenomenon might be attributed to the finding that the overall substrate consumption rate due to oxygen reduction and respiration is almost constant in the air-cathode MFCs. Oxygen leakage into the electrolyte can be inhibited due to the efficient oxygen reduction reaction on the surface of the cathode.

  16. Electrochemically exfoliated graphene anodes with enhanced biocurrent production in single-chamber air-breathing microbial fuel cells.

    PubMed

    Najafabadi, Amin Taheri; Ng, Norvin; Gyenge, Előd

    2016-07-15

    Microbial fuel cells (MFCs) present promising options for environmentally sustainable power generation especially in conjunction with waste water treatment. However, major challenges remain including low power density, difficult scale-up, and durability of the cell components. This study reports enhanced biocurrent production in a membrane-free MFC, using graphene microsheets (GNs) as anode and MnOx catalyzed air cathode. The GNs are produced by ionic liquid assisted simultaneous anodic and cathodic electrochemical exfoliation of iso-molded graphite electrodes. The GNs produced by anodic exfoliation increase the MFC peak power density by over 300% compared to plain carbon cloth (i.e., 2.85Wm(-2) vs 0.66Wm(-2), respectively), and by 90% compared to conventional carbon black (i.e., Vulcan XC-72) anode. These results exceed previously reported power densities for graphene-containing MFC anodes. The fuel cell polarization results are corroborated by electrochemical impedance spectroscopy indicating three times lower charge transfer resistance for the GN anode. Material characterizations suggest that the best performing GN samples were of relatively smaller size (~500nm), with higher levels of ionic liquid induced surface functionalization during the electrochemical exfoliation process.

  17. Real-time monitoring of bioaerosols via cell-lysis by air ion and ATP bioluminescence detection.

    PubMed

    Park, Chul Woo; Park, Ji-Woon; Lee, Sung Hwa; Hwang, Jungho

    2014-02-15

    In this study, we introduce a methodology for disrupting cell membranes with air ions coupled with ATP bioluminescence detection for real-time monitoring of bioaerosol concentrations. A carbon fiber ionizer was used to extract ATP from bacterial cells for generating ATP bioluminescence. Our methodology was tested using Staphylococcus epidermidis and Escherichia coli, which were aerosolized with an atomizer, and then indoor bioaerosols were also used for testing the methodology. Bioaerosol concentrations were estimated without culturing which requires several days for colony formation. Correlation equations were obtained for results acquired using our methodology (Relative Luminescent Unit (RLU)/m(3)) and a culture-based (Colony Forming Unit (CFU)/m(3)) method; CFU/m(3)=1.8 × measured RLU/m(3) for S. epidermidis and E. coli, and CFU/m(3)=1.1 × measured RLU/m(3) for indoor bioaerosols under the experimental conditions. Our methodology is an affordable solution for rapidly monitoring bioaerosols due to rapid detection time (cell-lysis time: 3 min; bioluminescence detection time: <1 min) and easy operation.

  18. Electrochemically exfoliated graphene anodes with enhanced biocurrent production in single-chamber air-breathing microbial fuel cells.

    PubMed

    Najafabadi, Amin Taheri; Ng, Norvin; Gyenge, Előd

    2016-07-15

    Microbial fuel cells (MFCs) present promising options for environmentally sustainable power generation especially in conjunction with waste water treatment. However, major challenges remain including low power density, difficult scale-up, and durability of the cell components. This study reports enhanced biocurrent production in a membrane-free MFC, using graphene microsheets (GNs) as anode and MnOx catalyzed air cathode. The GNs are produced by ionic liquid assisted simultaneous anodic and cathodic electrochemical exfoliation of iso-molded graphite electrodes. The GNs produced by anodic exfoliation increase the MFC peak power density by over 300% compared to plain carbon cloth (i.e., 2.85Wm(-2) vs 0.66Wm(-2), respectively), and by 90% compared to conventional carbon black (i.e., Vulcan XC-72) anode. These results exceed previously reported power densities for graphene-containing MFC anodes. The fuel cell polarization results are corroborated by electrochemical impedance spectroscopy indicating three times lower charge transfer resistance for the GN anode. Material characterizations suggest that the best performing GN samples were of relatively smaller size (~500nm), with higher levels of ionic liquid induced surface functionalization during the electrochemical exfoliation process. PMID:26926591

  19. Aerosolized ZnO nanoparticles induce toxicity in alveolar type II epithelial cells at the air-liquid interface

    SciTech Connect

    Xie, Yumei; Williams, Nolann G.; Tolic, Ana; Chrisler, William B.; Teeguarden, Justin G.; Maddux, Bettye L.; Pounds, Joel G.; Laskin, Alexander; Orr, Galya

    2012-01-20

    The majority of in vitro studies characterizing the impact of engineered nanoparticles (NPs) on cells that line the respiratory tract were conducted in cells exposed to NPs in suspension. This approach introduces processes that are unlikely to occur during inhaled NP exposures in vivo, such as the shedding of toxic doses of dissolved ions. ZnO NPs are used extensively and pose significant sources for human exposure. Exposures to airborne ZnO NPs can induce adverse effects, but the relevance of the dissolved Zn2+ to the observed effects in vivo is still unclear. Our goal was to mimic in vivo exposures to airborne NPs and decipher the contribution of the intact NP from the contribution of the dissolved ions to airborne ZnO NP toxicity. We established the exposure of alveolar type II epithelial cells to aerosolized NPs at the air-liquid interface (ALI), and compared the impact of aerosolized ZnO NPs and NPs in suspension at the same cellular doses, measured as the number of particles per cell. By evaluating membrane integrity and cell viability 6 and 24 hours post exposure we found that aerosolized NPs induced toxicity at the ALI at doses that were in the same order of magnitude as doses required to induce toxicity in submersed cultures. In addition, distinct patterns of oxidative stress were observed in the two exposure systems. These observations unravel the ability of airborne ZnO NPs to induce toxicity without the contribution of dissolved Zn2+ and suggest distinct mechanisms at the ALI and in submersed cultures.

  20. Simultaneous processes of electricity generation and ceftriaxone sodium degradation in an air-cathode single chamber microbial fuel cell

    NASA Astrophysics Data System (ADS)

    Wen, Qing; Kong, Fanying; Zheng, Hongtao; Yin, Jinling; Cao, Dianxue; Ren, Yueming; Wang, Guiling

    2011-03-01

    A single chamber microbial fuel cell (MFC) with an air-cathode is successfully demonstrated using glucose-ceftriaxone sodium mixtures or ceftriaxone sodium as fuel. Results show that the ceftriaxone sodium can be biodegraded and produce electricity simultaneously. Interestingly, these ceftriaxone sodium-glucose mixtures play an active role in production of electricity. The maximum power density is increased in comparison to 1000 mg L-1 glucose (19 W m-3) by 495% for 50 mg L-1 ceftriaxone sodium + 1000 mg L-1 glucose (113 W m-3), while the maximum power density is 11 W m-3 using 50 mg L-1 ceftriaxone sodium as the sole fuel. Moreover, ceftriaxone sodium biodegradation rate reaches 91% within 24 h using the MFC in comparison with 51% using the traditional anaerobic reactor. These results indicate that some toxic and bio-refractory organics such as antibiotic wastewater might be suitable resources for electricity generation using the MFC technology.

  1. Oral administration of lipopolysaccharides activates B-1 cells in the peritoneal cavity and lamina propria of the gut and induces autoimmune symptoms in an autoantibody transgenic mouse

    PubMed Central

    1994-01-01

    About a half of the antierythrocyte autoantibody transgenic (autoAb Tg) mice, in which almost all B cells are detected in the spleen, lymph nodes, and Peyer's patches, but not in the peritoneal cavity, suffer from autoimmune hemolytic anemia. The occurrence of this disease is strongly linked to production of autoAb by activated peritoneal B-1 cells in the Tg mice. In this study, we have shown that oral administration of lipopolysaccharides (LPS) activated B-1 cells in the lamina propria of the gut as well as the peritoneal cavity in the healthy Tg mice and induced the autoimmune symptoms in all the Tg mice. The activation of peritoneal and lamina propria B-1 cells by enteric LPS is found not only in the anti-RBC autoAb Tg mice and normal mice but also in the aly mice which congenitally lack lymph nodes and Peyer's patches. These results suggest that B-1 cells in the two locations may form a common pool independent of Peyer's patches and lymph nodes, and can be activated by enteric thymus-independent antigens or polyclonal activators such as LPS. The induction of autoimmune hemolytic anemia in the Tg mice by enteric LPS through the activation of B-1 cells in the lamina propria of gut and in the peritoneal cavity suggests that B-1 cells and bacterial infection may play a pathogenic role in the onset of autoimmune diseases. PMID:8006578

  2. Sustainable design of high-performance microsized microbial fuel cell with carbon nanotube anode and air cathode.

    PubMed

    Mink, Justine E; Hussain, Muhammad Mustafa

    2013-08-27

    Microbial fuel cells (MFCs) are a promising alternative energy source that both generates electricity and cleans water. Fueled by liquid wastes such as wastewater or industrial wastes, the microbial fuel cell converts waste into energy. Microsized MFCs are essentially miniature energy harvesters that can be used to power on-chip electronics, lab-on-a-chip devices, and/or sensors. As MFCs are a relatively new technology, microsized MFCs are also an important rapid testing platform for the comparison and introduction of new conditions or materials into macroscale MFCs, especially nanoscale materials that have high potential for enhanced power production. Here we report a 75 μL microsized MFC on silicon using CMOS-compatible processes and employ a novel nanomaterial with exceptional electrochemical properties, multiwalled carbon nanotubes (MWCNTs), as the on-chip anode. We used this device to compare the usage of the more commonly used but highly expensive anode material gold, as well as a more inexpensive substitute, nickel. This is the first anode material study done using the most sustainably designed microsized MFC to date, which utilizes ambient oxygen as the electron acceptor with an air cathode instead of the chemical ferricyanide and without a membrane. Ferricyanide is unsustainable, as the chemical must be continuously refilled, while using oxygen, naturally found in air, makes the device mobile and is a key step in commercializing this for portable technology such as lab-on-a-chip for point-of-care diagnostics. At 880 mA/m(2) and 19 mW/m(2) the MWCNT anode outperformed the others in both current and power densities with between 6 and 20 times better performance. All devices were run for over 15 days, indicating a stable and high-endurance energy harvester already capable of producing enough power for ultra-low-power electronics and able to consistently power them over time. PMID:23899322

  3. Effects of air pollution on cell membrane integrity, spectral reflectance and metal and sulfur concentrations in lichens

    SciTech Connect

    Garty, J.; Cohen, Y.; Kloog, N.; Karnieli, A.

    1997-07-01

    The fruticose lichen Ramalina duriaei is generally considered to be sensitive to air pollution. In the present study the authors sought to determine whether thalli of this lichen collected in a remote unpolluted site (the HaZorea Forest, northeast Israel) and transplanted to the Ashdod region (southwest Israel) could provide information on the quality of the air in this area. For this purpose, the concentrations of Pb, Cu, Cd, Ni, Mn, Fe, S, Ca, Mg, Na, and K were determined in in situ thalli collected in the HaZorea Forest in March 1993 and in in situ and transplanted thalli retrieved in June 1993. The concentration of these elements in R. duriaei thalli was analyzed in comparison with physiological parameters such as the integrity of cell membranes, chlorophyll content, and alterations in reflectance responses from lichen thalli. Thalli transplanted to several industrial sites in the town of Ashdod for a period of 100 d accumulated high concentrations of Pb, Cd, Ni, Fe, S, Mg, Na, Ca, and K. The concentration of S in thalli transplanted to the Ashdod region was found to correlate with damage caused to cell membranes and showed and inverse correlation with the chlorophyll content and with the reflectance response of the lichen. The electrical conductivity values corresponding to membrane integrity in the lichen thallus showed an inverse correlation with the ratio of chlorophyll a to pheophytin a, indicating the integrity of the photobiontic chlorophyll and with normalized-difference vegetation index values corresponding to the reflectance response of the thallus. The chlorophyll integrity correlated with the reflectance response. Magnesium accumulated in the lichen thalli in dusty sites and was found to correlate with damage caused to membranes.

  4. Sustainable design of high-performance microsized microbial fuel cell with carbon nanotube anode and air cathode.

    PubMed

    Mink, Justine E; Hussain, Muhammad Mustafa

    2013-08-27

    Microbial fuel cells (MFCs) are a promising alternative energy source that both generates electricity and cleans water. Fueled by liquid wastes such as wastewater or industrial wastes, the microbial fuel cell converts waste into energy. Microsized MFCs are essentially miniature energy harvesters that can be used to power on-chip electronics, lab-on-a-chip devices, and/or sensors. As MFCs are a relatively new technology, microsized MFCs are also an important rapid testing platform for the comparison and introduction of new conditions or materials into macroscale MFCs, especially nanoscale materials that have high potential for enhanced power production. Here we report a 75 μL microsized MFC on silicon using CMOS-compatible processes and employ a novel nanomaterial with exceptional electrochemical properties, multiwalled carbon nanotubes (MWCNTs), as the on-chip anode. We used this device to compare the usage of the more commonly used but highly expensive anode material gold, as well as a more inexpensive substitute, nickel. This is the first anode material study done using the most sustainably designed microsized MFC to date, which utilizes ambient oxygen as the electron acceptor with an air cathode instead of the chemical ferricyanide and without a membrane. Ferricyanide is unsustainable, as the chemical must be continuously refilled, while using oxygen, naturally found in air, makes the device mobile and is a key step in commercializing this for portable technology such as lab-on-a-chip for point-of-care diagnostics. At 880 mA/m(2) and 19 mW/m(2) the MWCNT anode outperformed the others in both current and power densities with between 6 and 20 times better performance. All devices were run for over 15 days, indicating a stable and high-endurance energy harvester already capable of producing enough power for ultra-low-power electronics and able to consistently power them over time.

  5. Oral administration of diphenylarsinic acid, a degradation product of chemical warfare agents, induces oxidative and nitrosative stress in cerebellar Purkinje cells.

    PubMed

    Kato, Koichi; Mizoi, Mutsumi; An, Yan; Nakano, Masayuki; Wanibuchi, Hideki; Endo, Ginji; Endo, Yoko; Hoshino, Mikio; Okada, Shoji; Yamanaka, Kenzo

    2007-11-10

    A new clinical syndrome with prominent cerebellar symptoms in patients living in Kamisu City, Ibaraki Prefecture, Japan, is described. Since the patients ingested drinking water containing diphenylarsinic acid (DPA), a stable degradation product of both diphenylcyanoarsine and diphenylchloroarsine, which were developed for use as chemical weapons and cause severe vomiting and sneezing, DPA was suspected of being responsible for the clinical syndrome. The purpose of the present study was to elucidate prominent cerebellar symptoms due to DPA. The aim of the study was to determine if single (15 mg/kg) or continuous (5 mg/kg/day for 5 weeks) oral administration of DPA to ICR-strain mice induced oxidative and/or nitrosative stress in their brain. Significantly positive staining with malondialdehyde (MDA) and 3-nitrotyrosine (3-NT) was observed in the cerebellar Purkinje cells by repeated administration (5 mg/kg/day) with DPA for 5 weeks that led to the cerebellar symptoms from a behavioral pharmacology standpoint and by single administration of DPA (15 mg/kg). Furthermore, it is possible that the production of 3-NT was not caused by peroxynitrite formation. The present results suggest the possibility that arsenic-associated novel active species may be a factor underlying the oxidative and nitrosative stress in Purkinje cells due to exposure to DPA, and that the damage may lead to the cerebellar symptoms.

  6. Toxicity of copper oxide nanoparticles in lung epithelial cells exposed at the air-liquid interface compared with in vivo assessment

    PubMed Central

    Jing, Xuefang; Park, Jae Hong; Peters, Thomas M.; Thorne, Peter S.

    2015-01-01

    The toxicity of spark-generated copper oxide nanoparticles (CuONPs) was evaluated in human bronchial epithelial cells (HBEC) and lung adenocarcinoma cells (A549 cells) using an in vitro air-liquid interface (ALI) exposure system. Dose-response results were compared to in vivo inhalation and instillation studies of CuONP. Cells were exposed to particle-free clean air (controls) or spark-generated CuONPs. The number median diameter, geometric standard deviation and total number concentration of CuONPs were 9.2 nm, 1.48 and 2.27×107 particles/cm3, respectively. Outcome measures included cell viability, cytotoxicity, oxidative stress and proinflammatory chemokine production. Exposure to clean air (2 or 4 hr) did not induce toxicity in HBEC or A549 cells. Compared with controls, CuONP exposures significantly reduced cell viability, increased lactate dehydrogenase (LDH) release and elevated levels of reactive oxygen species (ROS) and IL-8 in a dose-dependent manner. A549 cells were significantly more susceptible to CuONP effects than HBEC. Antioxidant treatment reduced CuONP-induced cytotoxicity. When dose was expressed per area of exposed epithelium there was good agreement of toxicity measures with murine in vivo studies. This demonstrates that in vitro ALI studies can provide meaningful data on nanotoxicity of metal oxides. PMID:25575782

  7. Optimization of solar cells for air mass zero operation and study of solar cells at high temperatures, phase 4

    NASA Technical Reports Server (NTRS)

    Hovel, H. J.; Woodall, J. M.

    1980-01-01

    The Pd contact to GaAs was studied using backscattering, Auger analysis, and sheet resistance measurements. Several metallurgical phases were present at low temperatures, but PdGa was the dominant phase in samples annealed at 500 C. Ti/Pd/Ag contacts appeared to have the lowest contact resistance. Etchback epitaxy (EBE) was compared to saturated melt epitaxy (SME) method of growing liquid phase epitaxial layers. The SME method resulted in a lower density of Ga microdroplets in the grown layer, although the best solar cells were made by the EBE method. Photoluminescence was developed as a tool for contactless analysis of GaAs cells. Efficiencies of over 8 percent were measured at 250 C.

  8. System modeling of an air-independent solid oxide fuel cell system for unmanned undersea vehicles

    NASA Astrophysics Data System (ADS)

    Burke, A. Alan; Carreiro, Louis G.

    To examine the feasibility of a solid oxide fuel cell (SOFC)-powered unmanned undersea vehicle (UUV), a system level analysis is presented that projects a possible integration of the SOFC stack, fuel steam reformer, fuel/oxidant storage and balance of plant components into a 21-in. diameter UUV platform. Heavy hydrocarbon fuel (dodecane) and liquid oxygen (LOX) are chosen as the preferred reactants. A maximum efficiency of 45% based on the lower heating value of dodecane was calculated for a system that provides 2.5 kW for 40 h. Heat sources and sinks have been coupled to show viable means of thermal management. The critical design issues involve proper recycling of exhaust steam from the fuel cell back into the reformer and effective use of the SOFC stack radiant heat for steam reformation of the hydrocarbon fuel.

  9. Aluminum-air power cell: The M3-3 experiment

    NASA Astrophysics Data System (ADS)

    Maimoni, A.; Muelder, S. A.

    1985-03-01

    The M3-3 experiment was a test of the M3 cell coupled to a crystallizer and hydrocyclone for separation of coarse solids before return of electrolyte to the cell. It was essentially a repeat of the M3-2 experiment, but with increased emphasis to understand the sources of experimental error and the evolution of the particle size distributions during the course of the experiment. A new hydrocyclone, scaled to operation with 1 to 5 cells, was tested in conjunction with peristaltic pumps. The test ran at 14 A for 101 min, followed by 122 A for 269 min at 60 C. The main operational problem was failure of the rubber tubing in the peristaltic pump feeding the hydrocyclone. Primary results include reasonable agreement in the material balances and with the calculated crystallization rates, the 50% cut point of the new hydrocyclone at about 8 (MU)m, and the aluminate concentration decreased from 2.4 M to 1.4 M in 21 h at 30 C in a subsequent batch crystallization experiment. The particle size distributions do not change significantly on aging de-ionized water.

  10. Steam Methane Reformation Testing for Air-Independent Solid Oxide Fuel Cell Systems

    NASA Technical Reports Server (NTRS)

    Mwara, Kamwana N.

    2015-01-01

    Recently, NASA has been looking into utilizing landers that can be propelled by LOX-CH (sub 4), to be used for long duration missions. Using landers that utilize such propellants, also provides the opportunity to use solid oxide fuel cells as a power option, especially since they are able to process methane into a reactant through fuel reformation. One type of reformation, called steam methane reformation, is a process to reform methane into a hydrogen-rich product by reacting methane and steam (fuel cell exhaust) over a catalyst. A steam methane reformation system could potentially use the fuel cell's own exhaust to create a reactant stream that is hydrogen-rich, and requires less internal reforming of the incoming methane. Also, steam reformation may hold some advantages over other types of reforming, such as partial oxidation (PROX) reformation. Steam reformation does not require oxygen, while up to 25 percent can be lost in PROX reformation due to unusable CO (sub 2) reformation. NASA's Johnson Space Center has conducted various phases of steam methane reformation testing, as a viable solution for in-space reformation. This has included using two different types of catalysts, developing a custom reformer, and optimizing the test system to find the optimal performance parameters and operating conditions.

  11. Detonation cell size measurements in high-temperature hydrogen-air-steam mixtures at the BNL high-temperature combustion facility

    SciTech Connect

    Ciccarelli, G.; Ginsberg, T.; Boccio, J.L.

    1997-11-01

    The High-Temperature Combustion Facility (HTCF) was designed and constructed with the objective of studying detonation phenomena in mixtures of hydrogen-air-steam at initially high temperatures. The central element of the HTCF is a 27-cm inner-diameter, 21.3-m long cylindrical test vessel capable of being heating to 700K {+-} 14K. A unique feature of the HTCF is the {open_quotes}diaphragmless{close_quotes} acetylene-oxygen gas driver which is used to initiate the detonation in the test gas. Cell size measurements have shown that for any hydrogen-air-steam mixture, increasing the initial mixture temperature, in the range of 300K to 650K, while maintaining the initial pressure of 0.1 MPa, decreases the cell size and thus makes the mixture more detonable. The effect of steam dilution on cell size was tested in stoichiometric and off-stoichiometric (e.g., equivalence ratio of 0.5) hydrogen-air mixtures. Increasing the steam dilution in hydrogen-air mixtures at 0.1 MPa initial pressure increases the cell size, irrespective of initial temperature. It is also observed that the desensitizing effect of steam diminished with increased initial temperature. A 1-dimensional, steady-state Zel`dovich, von Neumann, Doring (ZND) model, with full chemical kinetics, has been used to predict cell size for hydrogen-air-steam mixtures at different initial conditions. Qualitatively the model predicts the overall trends observed in the measured cell size versus mixture composition and initial temperature and pressure. It was found that the proportionality constant used to predict detonation cell size from the calculated ZND model reaction zone varies between 10 and 100 depending on the mixture composition and initial temperature. 32 refs., 35 figs.

  12. Chronic Δ(9)-Tetrahydrocannabinol Administration Reduces IgE(+)B Cells but Unlikely Enhances Pathogenic SIVmac251 Infection in Male Rhesus Macaques of Chinese Origin.

    PubMed

    Wei, Qiang; Liu, Li; Cong, Zhe; Wu, Xiaoxian; Wang, Hui; Qin, Chuan; Molina, Patricia; Chen, Zhiwei

    2016-09-01

    Delta9-tetrahydrocannabinol (Δ(9)-THC) is the major psychoactive component of the cannabis plant. Δ(9)-THC has been used in the active ingredient of Marinol as an appetite stimulant for AIDS patients. Its impact on progression of HIV-1 infection, however, remains debatable. Previous studies indicated that Δ(9)-THC administration enhanced HIV-1 infection in huPBL-SCID mice but seemingly decreased early mortality in simian immunodeficiency virus (SIV) infected male Indian-derived rhesus macaques. Here, we determine the chronic effect of Δ(9)-THC administration using 0.32 mg/kg or placebo (PBO), i.m., twice daily for 428 days on SIVmac251 infected male Chinese-derived rhesus macaques. Sixteen animals were divided into four study groups: Δ(9)-THC(+)SIV(+), Δ(9)-THC(+)SIV(-), PBO/SIV(+) and PBO/SIV(-) (n = 4/group). One-month after daily Δ(9)-THC or PBO administrations, macaques in groups one and three were challenged intravenously with pathogenic SIVmac251/CNS, which was isolated from the brain of a Chinese macaque with end-staged neuroAIDS. No significant differences in peak and steady state plasma viral loads were seen between Δ(9)-THC(+)SIV(+) and PBO/SIV(+) macaques. Regardless of Δ(9)-THC, all infected macaques displayed significant drop of CD4/CD8 T cell ratio, loss of CD4(+) T cells and higher persistent levels of Ki67(+)CD8(+) T cells compared with uninfected animals. Moreover, long-term Δ(9)-THC treatment reduced significantly the frequency of circulating IgE(+)B cells. Only one Δ(9)-THC(+)SIV(+) macaque died of simian AIDS with paralyzed limbs compared with two deaths in the PBO/SIV(+) group during the study period. These findings indicate that chronic Δ(9)-THC administration resulted in reduction of IgE(+)B cells, yet it unlikely enhanced pathogenic SIVmac251/CNS infection in male Rhesus macaques of Chinese origin. PMID:27109234

  13. Chronic Δ(9)-Tetrahydrocannabinol Administration Reduces IgE(+)B Cells but Unlikely Enhances Pathogenic SIVmac251 Infection in Male Rhesus Macaques of Chinese Origin.

    PubMed

    Wei, Qiang; Liu, Li; Cong, Zhe; Wu, Xiaoxian; Wang, Hui; Qin, Chuan; Molina, Patricia; Chen, Zhiwei

    2016-09-01

    Delta9-tetrahydrocannabinol (Δ(9)-THC) is the major psychoactive component of the cannabis plant. Δ(9)-THC has been used in the active ingredient of Marinol as an appetite stimulant for AIDS patients. Its impact on progression of HIV-1 infection, however, remains debatable. Previous studies indicated that Δ(9)-THC administration enhanced HIV-1 infection in huPBL-SCID mice but seemingly decreased early mortality in simian immunodeficiency virus (SIV) infected male Indian-derived rhesus macaques. Here, we determine the chronic effect of Δ(9)-THC administration using 0.32 mg/kg or placebo (PBO), i.m., twice daily for 428 days on SIVmac251 infected male Chinese-derived rhesus macaques. Sixteen animals were divided into four study groups: Δ(9)-THC(+)SIV(+), Δ(9)-THC(+)SIV(-), PBO/SIV(+) and PBO/SIV(-) (n = 4/group). One-month after daily Δ(9)-THC or PBO administrations, macaques in groups one and three were challenged intravenously with pathogenic SIVmac251/CNS, which was isolated from the brain of a Chinese macaque with end-staged neuroAIDS. No significant differences in peak and steady state plasma viral loads were seen between Δ(9)-THC(+)SIV(+) and PBO/SIV(+) macaques. Regardless of Δ(9)-THC, all infected macaques displayed significant drop of CD4/CD8 T cell ratio, loss of CD4(+) T cells and higher persistent levels of Ki67(+)CD8(+) T cells compared with uninfected animals. Moreover, long-term Δ(9)-THC treatment reduced significantly the frequency of circulating IgE(+)B cells. Only one Δ(9)-THC(+)SIV(+) macaque died of simian AIDS with paralyzed limbs compared with two deaths in the PBO/SIV(+) group during the study period. These findings indicate that chronic Δ(9)-THC administration resulted in reduction of IgE(+)B cells, yet it unlikely enhanced pathogenic SIVmac251/CNS infection in male Rhesus macaques of Chinese origin.

  14. Effects of long-term administration of cancer-promoting substances on oral subepithelial mast cells in the rat.

    PubMed

    Sand, L; Hilliges, M; Larsson, P A; Wallstrom, M; Hirsch, J M

    2002-01-01

    The role of oral subepithelial mast cells in the defence against tumours is a matter of controversy. The effect of established and suggested carcinogens, such as the carcinogen 4-nitroquinoline-N-oxide (4-NQO) and Herpes simplex virus type 1 (HSV-1), in combination with oral snuff on lower lip subepithelial mast cells (MC) was studied in rats. The rats were exposed to prolonged use of oral snuff. The test substances were administered in a surgically created canal in the lower lip of the rats. There were 15 rats in each test group and 10 rats in the control group. The amount of countable subepithelial mast cells decreased significantly when the rat oral mucosa was exposed to the oral carcinogen 4-NQO but the effect of oral snuff and HSV-1 infection was weak. Our findings suggest that mast cells play a role in immunological cell defence against chemical carcinogens. Further studies are needed to clarify the mechanisms. PMID:12529973

  15. Fabrication of cell penetration enhanced poly (l-lactic acid-co-ɛ-caprolactone)/silk vascular scaffolds utilizing air-impedance electrospinning.

    PubMed

    Yin, Anlin; Li, Jiukai; Bowlin, Gary L; Li, Dawei; Rodriguez, Isaac A; Wang, Jing; Wu, Tong; Ei-Hamshary, Hany A; Al-Deyab, Salem S; Mo, Xiumei

    2014-08-01

    In the vascular prosthetic field, the prevailing thought is that for clinical, long-term success, especially bioresorbable grafts, cellular migration and penetration into the prosthetic structure is required to promote neointima formation and vascular wall development. In this study, we fabricated poly (l-lactic acid-co-ɛ-caprolactone) P(LLA-CL)/silk fibroin (SF) vascular scaffolds through electrospinning using both perforated mandrel subjected to various intraluminal air pressures (0-300kPa), and solid mandrel. The scaffolds were evaluated the cellular infiltration in vitro and mechanical properties. Vascular scaffolds were seeded with smooth muscle cells (SMCs) to evaluate cellular infiltration at 1, 7, and 14 days. The results revealed that air-impedance scaffolds allowed significantly more cell infiltration as compared to the scaffolds fabricated with solid mandrel. Meanwhile, results showed that both mandrel model and applied air pressure determined the interfiber distance and the alignment of fibers in the enhanced porosity regions of the structure which influenced cell infiltration. Uniaxial tensile testing indicated that the air-impedance scaffolds have sufficient ultimate strength, suture retention strength, and burst pressure as well as compliance approximating a native artery. In conclusion, the air-impedance scaffolds improved cellular infiltration without compromising overall biomechanical properties. These results support the scaffold's potential for vascular grafting and in situ regeneration.

  16. Histochemical and functional improvement of adipose-derived stem cell-based tissue-engineered cartilage by hyperbaric oxygen/air treatment in a rabbit articular defect model.

    PubMed

    Dai, Niann-Tzyy; Fan, Gang-Yi; Liou, Nien-Hsien; Wang, Yi-Wen; Fu, Keng-Yen; Ma, Kuo-Hsing; Liu, Jiang-Chuan; Chang, Shun-Cheng; Huang, Kun-Lun; Dai, Lien-Guo; Chen, Shyi-Gen; Chen, Tim-Mo

    2015-05-01

    Cartilage is exposed to compression forces during joint loading. Therefore, exogenous stimuli are frequently used in cartilage tissue engineering strategies to enhance chondrocyte differentiation and extracellular matrix (ECM) secretion. In this study, human adipose-derived stem cells were seeded on a gelatin/polycaprolactone scaffold to evaluate the histochemical and functional improvement of tissue-engineered cartilage after hyperbaric oxygen/air treatment in a rabbit articular defect model. Behavior tests showed beneficial effects on weight-bearing and rear leg-supporting capacities after treatment of tissue-engineered cartilage with 2.5 ATA oxygen or air. Moreover, positron emission tomography images and immunohistochemistry staining demonstrated hydroxyapatite formation and increased ECM synthesis, respectively, at the tissue-engineered cartilage graft site after high pressure oxygen/air treatment. Based on these results, we concluded that hyperbaric oxygen and air treatment can improve the quality of tissue-engineered cartilage in vivo by increasing the synthesis of ECM.

  17. Effect of intravenous administration of D-lysergic acid diethylamide on initiation of protein synthesis in a cell-free system derived from brain.

    PubMed

    Cosgrove, J W; Brown, I R

    1984-05-01

    An initiating cell-free protein synthesis system derived from brain was utilized to demonstrate that the intravenous injection of D-lysergic acid diethylamide (LSD) to rabbits resulted in a lesion at the initiation stage of brain protein synthesis. Three inhibitors of initiation, edeine, poly(I), and aurintricarboxylic acid were used to demonstrate a reduction in initiation-dependent amino acid incorporation in the brain cell-free system. One hour after LSD injection, there was also a measurable decrease in the formation of 40S and 80S initiation complexes in vitro, using either [35S]methionine or [35S]Met-tRNAf. Analysis of the methionine pool size after LSD administration indicated there was no change in methionine levels. Analysis of the formation of initiation complexes in the brain cell-free protein synthesis system prepared 6 h after LSD administration indicated that there was a return to control levels at this time. The effects of LSD on steps in the initiation process are thus reversible.

  18. High Fat Diet-Induced Skeletal Muscle Wasting Is Decreased by Mesenchymal Stem Cells Administration: Implications on Oxidative Stress, Ubiquitin Proteasome Pathway Activation, and Myonuclear Apoptosis.

    PubMed

    Abrigo, Johanna; Rivera, Juan Carlos; Aravena, Javier; Cabrera, Daniel; Simon, Felipe; Ezquer, Fernando; Ezquer, Marcelo; Cabello-Verrugio, Claudio

    2016-01-01

    Obesity can lead to skeletal muscle atrophy, a pathological condition characterized by the loss of strength and muscle mass. A feature of muscle atrophy is a decrease of myofibrillar proteins as a result of ubiquitin proteasome pathway overacti