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Sample records for cell nenryo denchi

  1. Fuel cell; Nenryo denchi

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, T. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1999-07-20

    More than 100 sets of phosphoric acid fuel cells (PAFC) have been installed by now, and accumulated operation performance exceeding 40 thousand hours, which is regarded as a development target, has been achieved. Further, there are also PAFCs that have achieved continuous operation performance exceeding 9,000 hours, thus being most approachable to practical use. On the other hand, developments of the solid oxide fuel cells (SOFC) and the molten carbonate fuel cells (MCFC), which operate at high temperatures, have high power generation efficiencies due to the capability of operating associatively with gas turbines or vapor turbines, and may use coal gasified gases as fuels, are carried out for an aim of realizing the practical use at the begging of the 21st century. Further, in recent years, researches and developments of the polymer electrolyte fuel cells (PEFC) have been accelerated mainly in vehicle business for the purpose of using PEFC as power sources for movable bodies, and researches and development for accelerative development of cell stacks and power generation systems are executed. In this paper, situations of the researches and developments in respect to the above-mentioned four kinds of fuel cells are summarily introduced. (NEDO)

  2. Solid electrolyte fuel cell. Kotai denkaishitsu nenryo denchi sochi

    Energy Technology Data Exchange (ETDEWEB)

    Okuyama, R. (Yuasa Battery Co. Ltd., Osaka (Japan))

    1992-09-22

    The honeycomb structure has been proposed for the solid electrolyte fuel cell to increase the output power of the cell. However, the honeycomb structure has a shortcoming or difficulty in formation of air electrode, fuel electrode and solid electrolyte membrane as well as in fabrication of air manifold and fuel manifold. This invention solves the problem. In the solid electrolyte cell whose power generation component is composed by laminating the solid electrolyte membrane and the air electrode on the surface of the hollow polygonal column shape fuel electrode, the power generation component and the current conductive component are put together by inserting the metal oxide between the air electrode on the surface of the power generation component and the surface of the current conductive component. With this structure, the parallel connection of a number of solid electrolyte fuel cells by means of electro-conductive component metal oxide in the current conductive component can be achieved, resulting an increase in output power. Examples of the said metal oxide are LaMnO3, LaCoO3, CaMnO3 or LaCrO3 doped with Sr or Ca. 9 figs.

  3. Present situation and subjects of fuel cell development. Nenryo denchi kaihatsu no genjo to kadai

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Yoshisada (Fuji Electric Co., Ltd., Tokyo, (Japan))

    1990-02-10

    This report explains the present situation of the development of phosphoric acid type fuel cells. Tests on New Energy and Industrial Technology Development Organization {prime} s 1,000kW plant for distribution arrangement and two plants (two electric power companies) to substitute thermal power were completed in 1989. With the success of these tests, Japanese technologies on fuel cells were improved greatly. Two projects on on-site type cells for detached islands and for industry using city gas are on progress. In civil circles, there are several projects on progress such as Tokyo Power Company {prime} s Goi plant of 11MW whose operation is going to be started in 1991. As for development situation abroad, the USA has carried out field tests on a 4.5MW plant and many 12.5KW and 43kW plants for gas utility, and it is now developing a 200kW plant. On the other hand, European countries make researches mainly on aldali type fuel cells, and they make it a policy to purchase elemental cells of phosphoric acid type from Japan and the USA. 1 fig., 3 tabs.

  4. Survey on commercial use of fuel cells; Nenryo denchi ni kansuru jitsuyoka no tame no chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The basic survey was carried out for the future approach to R & D of fuel cells. Phosphoric acid fuel cell (PAFC) is in the stage of demonstration research and field test supported by subsidy after the end of Sunshine project. Its reliability and durability problems are being solved, and its cost reduction is only one problem for practical use. Distributed systems or on-site systems will be used utilizing its excellent environmental characteristics. Molten carbonate fuel cell (MCFC), solid oxide one (SOFC) and polymer electrolyte one (PEFC) under development were thus surveyed. The following are surveyed: (1) Contribution to a human society such as improvement of energy demand/supply structure and environmental protection, (2) Technological items such as outlook for R & D, validity of developmental issues, comparison between various R & D and significance in industrial promotion, (3) Economic items such as profitability and feasible period, and (4) Social items such as sociability, compatibility to needs, possibility of locations, international meaning, market scale and promotion scenario. 90 refs., 67 figs., 96 tabs.

  5. Solid oxide electrolyte fuel cell system. Kotai denkaishitsu nenryo denchi sochi

    Energy Technology Data Exchange (ETDEWEB)

    Okuyama, R. (Yuasa Battery Co. Ltd., Osaka (Japan))

    1992-09-17

    To improve the solid oxide electrolyte fuel cell for higher output, provision of manifolds for air and fuel in honeycomb structure has been proposed. The method of making them in the honeycomb structure has a problem of difficulty in the fabrication. This invention is concerned with a structure, wherein the structural body of the power generating member and that of the electric conducting member are connected between the air electrode on the surface of the structural body of the power generating member and that on the surface of the structural member of the electric conducting member with interposed conductive metal oxide, and the interconnecting member of the power generating structural member body is connected to the air electrode on the surface of the structural member of another power generating member. As a result of this structure, high output solid oxide electrolyte fuel cell can be fabricated by connecting the structural bodies of the power generating members and those of the conducting members in regular succession. Strontium or calcium doped LaMnO3, LaCoO3, CaMnO3, and LaCrO3 are used as the metal oxides. 10 figs.

  6. General report on the results of the development of fuel cell technology such as urban energy center. Evaluation study of life of phosphoric acid fuel cells (fiscal 1995 and 1996); Toshi energy center nado nenryo denchi gijutsu kaihatsu kenkyu seika sogo hokokusho. Rinsangata nenryo denchi jumyo hyoka kenkyu (1995 kara 1996 nendo)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Receiving subsidies from MITI, NEDO carried out this project in fiscal 1995 and 1996 as a joint research with Technology Research Association for Phosphoric Acid Fuel Cell Power Generation System and others. The project aimed at developing the accelerated test method which can evaluate in a short time the cell life of phosphoric acid fuel cells (PAFC) and the lowering of characteristics. The accelerated test method of PAFC life is thought to be a tool indispensable for the promotion of commercialization, but the accelerated test method like the usual material evaluation has not yet been established. To solve this problem, procedures were developed to rationally plan the accelerated test on short stacks of full scale based on the small cell test data. Here, to rationally estimate the operational state under actual conditions based on the data on the accelerated test, it is necessary to fully understand the mechanism of deterioration of PAFC. By conducting in parallel the element study for the basic elucidation of cell deterioration phenomena, obtained was the useful information/knowledge which back up the results of the accelerated test scientifically. 168 figs., 33 tabs.

  7. Achievement report for fiscal 1997 on joint research to develop fuel cell technologies for urban energy centers. Research on evaluating life of phosphoric acid fuel cells; 1997 nendo toshi energy center nado nenryo denchi gijutsu kaihatsu kyodo kenkyu seika hokokusho. Rinsangata nenryo denchi jumyo hyoka kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    This paper discusses life evaluation on phosphoric acid fuel cells of urban energy center type for regional energy supply and on-site type to be installed in buildings. Operation characteristics tests and disassembly checks allow to identify factors for voltage decrease, and estimate the life therefrom particularly if the voltage decrease is caused from catalyst activity. The time before 10% decrease value is reached is now about 40,000 hours. The creep analysis method that has been developed recently can predict deformation in full-size reformers nearly exactly, and is effective in operating the reformer and evaluating the life at the design stage. Creep buckling is the critical value, which is caused by ecliptic deformation of internal tubes in the second catalyst layer. In a heat exchanger for fuel gas preheating, carbon in the reformed gas is carbonized and deposited due to catalytic action of nickel in the brazing material that bonds plates and fins in the heat exchanger. Iron also has a possibility of performing catalytic action. In the on-site type 1,000-kW class fuel cells, no structural problems have been presented even after the operation has been stopped. In order to extend time interval between phosphoric acid supply into the cells, it is necessary to reduce difference in the remaining phosphoric acid amounts in the stack lamination direction and in the cell flat surface. (NEDO)

  8. Fiscal 1998 research report. Survey on data collection for development of new energy technology (fuel cell); 1998 nendo chosa hokokusho. Shin energy gijutsu kaihatsu kankei data shu sakusei chosa (nenryo denchi)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    This report is composed of Part 1: the development trend of fuel cells in fiscal 1998, and Part 2: the collected data and appendices. Part 1 includes 4 chapters, (1) The outline of the development trend, (2) Stationary fuel cell, (3) The development trend of fuel cell vehicles, and (4) The development trend of small transportable fuel cells. The report newly includes the development trend of small-capacity fuel cells and the report on 1998 Fuel Cell Seminar notable as an international conference on fuel cell summarizing the trend of fuel cells in fiscal 1998, as compared with the fiscal 1997 report. Part 2 is the collected data on domestic and foreign demonstration operation results of fuel cells, and technical development of every fuel cell. In addition to various collected data on the whole of fuel cells and their use techniques, Part 2 includes the principle, features, system configuration, performance simulation technique, application and market analysis of fuel cells, and the national policy and concerned laws on a subsidy system for introduction of fuel cells, for example. (NEDO)

  9. FY 1994 Report on the results of the joint research project for optimum introduction of development of fuel cell technologies for urban energy centers; 1994 nendo toshi energy center nado nenryo denchi gijutsu kaihatsu saiteki donyu chosa seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    Described herein are the FY 1994 results of the joint research project for optimum introduction of development of fuel cell technologies for urban energy centers or the like. The necessary economic conditions for introduction of a fuel cell system to be competitive with the conventional system which individually supplies electric power and heat are 250,000 yen/kW as the construction unit cost, 0.10m{sup 2}/kW as the installation area, 5 years as the cell body life, use of an inexpensive fuel gas (2 to 6 yen/Mcal). Moreover, it is an indoor system which shall have the operational characteristics to follow daily demand fluctuations while operating under the optimum conditions in the urban redevelopment area considered. A 5,000kW-class fuel cell plant burning fuel gas (2 yen/Mcal) will need a total floor area of approximately 400,000 m{sup 2} in an energy-intensive office type demand area. These conditions shall be met in order to economically introduce the 5,000kW-class plant. It is also necessary to compare the plant with the competitive cogeneration plants. The specifications for the prototype now under consideration are sufficient for the energy-saving effect, and it is premised that these specifications and characteristics are secured. (NEDO)

  10. Solar cell module. Taiyo denchi module

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko.

    1990-01-24

    This invention concerns a module frame of solar cell and a solar cell module using this frame. In particular, it concerns a frame and a module useful for the CdS/CdTe or CdS/CuInSe {sub 2} based cell. In the existing solar cell module, sealant is packed in between the edges of a glass substrate, a resin layer and a back protective thin film, etc. and a grooved frame of U-shaped section. For the sealant, silicon based resin and butyl rubber based resin are used many times, but either resin has defects such as their overflow from the module structure. In order to solve these defects, this invention proposes to provide stair-shaped protrusions along the four sides of the bottom of the box frame (herein after called the lower frame) of the module and at the same time, provide a groove for pooling the sealant at the portion where such protrusion meets the side wall, furthermore to provide depressions for pooling the sealant at the upper edge inside the side wall of the lower frame or to punch holes at the corners of the bottom of the lower frame. 9 figs.

  11. Solar cell module. Taiyo denchi module

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko; Matsumoto, Hitoshi; Komatsu, Yasumitsu; Shirai, Sadaharu.

    1989-09-29

    In the solar cell module of this invention, such junctions as CdS/CdTe or CdS/CuInSe {sub 2} are contained as a photoelectromotive force part coexists with air in a closed space which consists of glass, metal parts and a bonding resin layer; the photoelectromotive force part is coated either with a fluorine resin or a silicone resin. The fluorine resin contains a fundamental skeleton of an alternative copolymer of fluoroolefin and a hydrocarbon-based vinyl monomer; the silicone resin has three types, i.e., addition-reacted, condensated or UV-curing type, and the released oxygen is sealed in the closed space. The resin layer which adheres the glass and the metal plate is a thermoplastic resin which is polyethylene modified by copolymerization of acid anhydride. By this, the reliability of the solar cell module was enhanced. 3 figs.

  12. Solar cell module. Taiyo denchi module

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko; Matsumoto, Hitoshi.

    1989-09-06

    In the conventional solar cell module, the cell cost is elevated because the cross sections of the cell edge is surrounded with frames of various shape and the gap is filled with a sealant. In additionn, the top end of the module frame is placed roughly 1 mm above the glass surface; the photoelectromotive force part is covered with such deposits as soils and sands, thus badly affecting the photovoltaic generation. In this invention, weather-proof opaque paint is coated around the surface glass to interrupt the light irradiation to the adhesive resin layer between the glass and the back sheet, thus preventing the degradation of the resin layer. Cost is low because of using a thin film. The light interruption by the deposits can be prevented. The photoelectromotive force element is a n-type CdS film or CdS/CdTe. The resin layer around the glass is a thermoplastic polyolefin which is modified with acid anhydrides. 5 figs.

  13. Sollar cell module; Taiyo denchi mojuru

    Energy Technology Data Exchange (ETDEWEB)

    Komori, A.; Mori, T.; Shiotsuka, H.; Kataoka, I.; Yamada, S.

    1997-02-25

    This invention relates to a solar cell module composed of a photovoltaic device with at least one layer of a semiconductor photoactive layer as a photoelectric conversion material and a covering material, in which thermoplastic transparent organic polymer resin of a gel fraction more than 80% is used as the covering material. This polymer resin has a diminution rate of ultraviolet absorption between 5 and 50% when exposed to an atmosphere of a temperature of 150{degree}C for 72 hours. The thermoplastic transparent polymer resin of a gel fraction more than 80% is cross-linked sufficiently and is hard to deteriorate. Therefore, the adhesion between the thermoplastic transparent polymer resin and the uppermost resin film is secured owing to no emergence of the glass fiber and moreover, reinforcement of the thermoplastic transparent polymer resin with glass fiber enable to reduce the thickness of the thermoplastic transparent polymer resin while securing the scratch resistance. 6 figs., 1 tab.

  14. Fiscal 1997 report on the results of the international standardization R and D. R and D of the standardization of a method to test acceleration life of phosphorous acid fuel cells; 1997 nendo seika hokokusho kokusai hyojun soseigata kenkyu kaihatsu. Rinsangata nenryo denchi no kasoku jumyo shiken hoho no hyojunka ni kansuru kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    As for fuel cells, which are expected as a new clean energy, the R and D are being proceeded with in various fields of the world, but the standardization has not been made both in Japan and abroad. In Japan, the situation is that the information on technical terms, indication method, performance test method, and environment/safety test methods of the phosphorous acid fuel cell power generation is publicly spread. In relation to the international promotion of fuel cells to be predicted, it is necessary to internationally standardize cells themselves which are a key component of fuel cell power generation facilities. Phosphorous acid fuel cells are expected of the earliest commercialization of all, but the common test method to evaluate life characteristics of the cell stack has not been established yet. In the R and D, for the purpose of internationally standardizing test methods to evaluate life characteristics of the cell stack, a study on the acceleration life test method of phosphoric acid fuel cells was conducted in terms of the technical trend, data, standard, etc. A plan was prepared on general rules of the method to test acceleration life at the cell reaction part of the small cell, and activities also were started for setting up a technical committee for the fuel cell power system in President`s Advisory Committee on Future Technology. 29 figs., 20 tabs.

  15. Fiscal 1993 international research cooperation project. Feasibility study of finding out the seeds of international joint research (technology for environmental preservation using biotechnology, technology for effective use unused hydrocarbon resource, technology of solid electrolyte fuel cells for high-efficient electric vehicles); 1993 nendo kokusai kenkyu kyoryoku jigyo. Kokusai kyodo kenkyu seeds hakkutsu no tame no FS chosa (biotechnology ni yoru kankyo taisaku gijutsu, miriyo tanka suiso shigen no yuko riyo gijutsu, kokoritsu denki jidosha no kotai denkaishitsu nenryo denchi gijutsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    This project is aimed at internationally cooperating in the R and D of industrial technology and improving industrial technology of Japan. For it, the following three technologies were investigated: 1) environmental preservation technology using biotechnology, 2) technology for effective use of unused hydrocarbon resource, 3) solid electrolyte fuel cell (SOFC) technology for high-efficient electric vehicles. In 1), bio-remediation is a choice as the result of trially using technologies for remediation of the environment polluted by pollutant, but it is not a technically completed one, but one which will be improved by trial and error. By the application of gene engineering, the use of gene recombination enables wide spread of decomposition genes. In 2), technical subjects were studied such as superheavy distillate, oil shale, coalhead methane and methane hydrate. In 3), designed were cylinder type and planar type SOFC of 850degC operation and 10kW output. Accumulation and weight of a total SOFC system are 81 liters and 100 kg in cylinder type and 136 liters and 200 kg in planar type. The vehicle can be equipped with the SOFC. 171 refs., 72 figs., 54 tabs.

  16. Flexible solar cell; Katosei taiyo denchi no seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Kato, S.

    1997-06-10

    Polyethylene-vinyl acetate (EVA) film used as a sealing resin in manufacturing of a flexible solar cell has a problem that it stretches and shrinks so as to unable to draw out from the roll of the component materials without size change or deflection while controlling the tensile force. This invention aims to present a manufacturing method of a flexible solar cell to enable the drawing out from the roll of the component materials and the winding after sealing. In this invention, an insulating sealant EVA is pressed onto a flexible supporting substrate, followed by pressing a solar cell device onto the exposed surface of the EVA on the supporting substrate. At least a later process of the pressing processes is conducted below 120degC under reduced pressure. The supporting substrate may be a peelable material or may be pressed onto a film with peelable surface so as to expose the EVA by peeling after sealing. Otherwise, the use of a supporting substrate with weatherability and low peelability may afford a flexible solar cell with a weather resisting protective film. 6 figs.

  17. Manufacturing facility of solar cell. Taiyo denchi no seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Makoto; Takagi, Akira; Ban, Noriji; Ishihara, Mikiji.

    1990-01-09

    When a p-n junction type CdTe solar cell is manufactured by the metal-organic chemical vapor deposition (MOCVD) , dislocation of the position of its p-n junction interface from the specified position and dislocation of the distribution of impurities in the direction of depth at the p layer and the n layer occur, inhibiting the manufacture of the p-n junction. In order to eliminate the above problem and manufacture a p-n junction type CdTe solar cell with high energy conversion efficiency by the MOCVD, this invention proposes to form a n type CdTe layer as the first layer on a substrate at the first substrate temperature, form a non-dope CdTe layer as the second layer at the second substrate temperature lower than the first substrate temperature, form a p type CdTe layer as the third layer at the third substrate temperature lower than the first substrate temperature and from the thickness that the second layer does not remain as an i layer due to diffusion of the impurities from the first and third layers and yet mutual diffusion of the impurities between the first and third layers is controlled. 2 figs., 1 tab.

  18. Solar cell module and its manufacturing process. Taiyo denchi module oyobi sono seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko.

    1990-01-12

    The reason behind the high power costs of solar cells is expensiveness of solar cell element devices and its modules, and efforts to lower the costs of the former have so far been made, but the same efforts are necessary for the latter too. Concerning CdS/CdTe or CdS/CuInSe {sub 2} solar cells, when the oxygen concentration in the atmosphere available around the element device becomes less, deterioration of its performance occurs. Heretofore, concerning the above two kinds of solar cell modules, a stress was placed on prevention of infiltration of water into the element device and no concern has been paid to the effect of oxygen. Consequently, several issues have remained unsolved like alteration of crude material around the element of module with material which does not react with oxygen or absorb it. In view of the above, this invention proposes to make a solar cell module of the structure that thermosetting resin is set at the peripheral blank part of the substrate with no formation of solar cell element and a box with a flange is applied to that part in the heated and pressurized condition at the time of making protection of the back of the CdS/CdTe or CdS/CuInSe {sub 2} solar cell element device. 7 figs.

  19. Installation mechanism of solar cells for an airship. Hikosen'yo taiyo denchi sochaku kiko

    Energy Technology Data Exchange (ETDEWEB)

    Ouchi, K. (Tokyo (Japan)); Tanaka, K. (Yokohama (Japan))

    1994-06-10

    This invention aims to present an installation mechanism to equip solar cell units on the envelope of the hull of an airship and the mechanism follows easily expansion and contraction of the envelope material of the hull of the airship and is detachable. This invention presents the installation mechanism of solar cells for an airship, in which a suitable number of supporting connectors are installed on a front part, a back part and both sides of number of elastic supports fixed to each solar cell unit, lead connectors are equipped on the leads of the solar cell units, a solar cell extensible module is formed by mutual connection of the elastic supports and the leads via the supporting connectors and lead connectors in a detachable way, and the solar cell extensible modules are installed on the envelope of the hull of the airship so that the solar cell extensible modules cover the envelope without direct fixation of the elastic support to the envelope. 7 figs.

  20. To the partnership in Kanegafuchi Chemical Industry and solar cell; Kaneka, taiyo denchi de teikei he

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    Kanegafuchi Chemical Ind. clarified that the consultation was advanced in the direction in which the business cooperates with BP Amoco Corp. in international oil majors on the solar cell business on 11 th capital. In full amount fund subsidiary of the bell pool chemistry, the solar cell making and selling company is established in the joint venture in Europe and America, Asia, when the BP Amoco Corp. does capital participation in money mosquito solar tech which is the production marketer of solar cell. The plan which develops the amorphous solar cell of low cost which the bell pool chemistry developed in the world. The consultation of the partnership is also arranging prospect in the end June, and it seems to greatly jump by uniting with the BP Amoco Corp. of the largest hand. (translated by NEDO)

  1. Solar cell panel and its connection method. Taiyo denchi panel narabini sono setsuzoku hoho

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, A.; Hasunuma, M.; Kuroki, K. (Sanyo Electric Co. Ltd., Osaka (Japan))

    1992-08-14

    The wiring operation after a solar cell panel is installed outdoors is dangerous of an electrical shock because the solar cell generates power as soon as it receives the sunlight. An object of the invention is to secure safety in the wiring operation after the outdoor installment of a solar cell panel. The invention concerns a method of the installment of a solar cell panel, in which a solar cell panel with a shading measure on its light-receiving surface is installed outdoors and the shading measure is removed after the wiring operation to lead the photovoltaic power generated at the panel to the load. The shading measure includes a light-shielding peelable surface protective membrane, a surface protective material composed of an opaque material attachable on and removable from the panel, a membrane applied with an opaque material and removable mechanically after the wiring operation, a membrane applied with water-soluble material mixed with an opaque material and removable with washing with water after the wiring operation, and a membrane composed of paraffin or vaseline which is opaque at a room temperature and transparent at a high temperature. 4 figs.

  2. Manufacture method of a solar cell. Taiyo denchi no seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Kitamura, S.; Hanabusa, A.; Arita, T.; Murosono, M.

    1993-12-24

    Conventional manufacture methods of a CdS/CdTe solar cell have problems that a blurred layer of CdTe printing and a redeposition layer of CdTe firing exist at a CdS contact surface and the contact width between the CdS film and its electrode AgIn film is required to be larger than 0.30 mm in order to reduce the contact resistance and to give a highly efficient solar cell. This invention aims to provide a manufacture method of a solar cell in which a CdS film of the window layer and a CdTe film of the optical absorption layer are stacked successively followed by the formation of a carbon film as an acceptor material on the CdTe film, and the surface of the CdS film is treated by laser irradiation by the use of a mask of the carbon film. Consequently, a clean surface is obtained between the CdS film and the electrode AgIn film so as to reduce the contact resistance and the contact width between the CdS film and the AgIn film can be reduced so that a highly efficient solar cell can be produced. 5 figs.

  3. Amorphous semiconductor solar cell and manufacturing method. Hishoshitsu handotai taiyo denchi oyobi sono seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Sanjuku, T. (Taiyo Yuden Co. Ltd., Tokyo (Japan))

    1991-07-19

    This invention provides a manufacturing method of a transparent conductive film for an amorphous semiconductor soler cell, which can be easily molded with less cost without using a vacuum film formation process. In other words, in this invention, an ITO, which is practical for use with low ilumination intensity, is obtained by thinly coating a solution mixture of organic indium and organic tin compounds on an amorphous semiconductor layer followed by a heat treatment. In an amorphous semiconductor solar cell comprising a back electrode, amorphous semiconductor layer, a transparent conductive layer and a protective layer laminated sequentially on a surface insulated metal substrate, the said transparent conductive film is one wherein a solution mixture of organic indium and organic tin compounds is thinly coated on an semiconductor layer by means of a dipping process, dried, and heat-treated to form a film.

  4. Nickel oxide-hydrogen secondary cell. Nickel sankabutsu suiso niji denchi

    Energy Technology Data Exchange (ETDEWEB)

    Sugano, Keneichi; Kanda, Motoki; Sato, Yuji; Hayashida, Hirotaka.

    1989-11-15

    In a nickel oxide - hydrogen secondary cell, if a nickel electrode, which is not chemically treated, is used as a positive electrode, hydrogen will accummulates in a negative electrode consisting of a hydrogen storage alloy in the early stage of charge/discharge cycle, thus reducing the life of the cell. In this invention, by letting the electrolytic solution of the cell contain a compound which supplies the dissolved oxygen to the electrolyte, and reacting the hydrogen in the negative electrode while in the initial charging with dissolved oxygen in the electrolyte solution, accummulation of hydrogen in the negative electrode is prevented. The dissolved oxygen ddoner is an oxides or peroxides which generate oxygen by decomposition. The example is KO {sub 2}, O {sub 3}, H {sub 2} O {sub 2}, BaO {sub 2}, CaO {sub 2}, MgO {sub 2}, K {sub 2} O {sub 2} and Na {sub 2} O {sub 2}. It is preferred that these oxides or peroxides are contained in a microcapsule, gel or porous membrane. 4 figs.

  5. Elongation of lifetime of photosynthetic biofuel-cells containing immobilized algae; Koteika aiso wo mochiita kogosei biseibutsu denchi no chojumyoka

    Energy Technology Data Exchange (ETDEWEB)

    Yagishita, T.; Sawayama, S.; Inoue, S.; Ogi, T. [National Institute for Resources and Environment, Tsukuba (Japan)

    1994-12-08

    An experimental study is performed for elongation of lifetime of photosynthetic biofuel-cells using the living blue-green algae and a mediator. In the experiment, correlation between a current generated from cultured Anabaena and the life of the cells is investigated. Anabaena is recovered from the cells after the cells are operated for 10 hours in the dark and is cultured for 10 hours under irradiation with a Xe lamp and ventilation of 3 % CO2. Thereafter, immobilized Anabaena is returned into the cells and the cells are again actuated in repetition. Three load resistances 1 K ohm, 700 ohm, 400 ohm are employed and operation time of the current is lengthened under any conditions compared with the case where the cells are continuously operated. Further, provided a generated current is limited to 0.6 mA or lower, the current is not lowered even if the cells are operated for 90 hours. It is concluded that provided Anabaena is cultured after the electricity of 6.4 mA/h per the amount of chlorophyl in Anabaena is taken out, an output of the cells is kept unchanged for a long time. 7 refs., 4 figs., 1 tab.

  6. Present situation and perspective of space solar cells. Uchuyo taiyo denchi no genjo to kongo no tenkai

    Energy Technology Data Exchange (ETDEWEB)

    Suzjki, A.; Saga, T.; Hisamatsu, T. (Sharp Corp., Osaka, (Japan))

    1991-09-05

    The following items are descrided: (1) Although CdTe and GaAs are the excellent meterials for solar cells in terms of conversion efficiency, no candidates superior to Si has been discovered when they are judged comprehensively from manufacturing techniques and prices; (2) Space solar cells are demanded of such characteristics as being high in output, hard to deteriorate because of rediation, light in weight and high in reliability. The materials that have reached the level of practical use are those three, namely, Si, GaAs, and InP. The two kinds other than Si have higher conversion efficiency and less rediation-induced deterioration, but disadvantages in weight and price. Monocrystal silicon is currently the mainstream for space solar cell use, and the other two kinds are believed to be used in satellites for some special applications in the form of complementing the silicon crystals. Descriptions are given also on various space solar cells underdevelopment in laboratory stages and the development of the solar power generating satellte technology to begin under the auspices of the Ministry of International Trede and Industry. 33 refs., 3 figs., 2 tabs.

  7. Estimation of the charge quantity from solar cell to battery; Taiyo denchi ni yoru chikudenchi eno juden yosoku

    Energy Technology Data Exchange (ETDEWEB)

    Tsutsumi, K.; Nishitani, M. [Daiichi University, College of Technology, Kagoshima (Japan)

    1996-10-27

    In performing an experiment of running a small electric vehicle by installing solar cells in it and by charging the storage battery at a specific voltage, an estimation was made on the charge quantity to the battery for each solar altitude and inclination of a module at different hours. The solar altitude was determined at Daiichi University, College of Technology, according to the month and the time of day from a formula using day-declination and time equation of a chronological table of science. The quantity of global solar radiation was determined by resolving the solar radiation into its direct and diffuse components on the basis of the extra-terrestrial solar radiation quantity with the change in radius vector taken into consideration; and then, the global solar radiation on the inclined face was obtained from the angle of inclination and incidence. On the roof of a Daiichi University building, solar cell modules were installed facing north and south at 0{degree}, 30{degree}, 45{degree}, 60{degree} and 90{degree} each, so that a short-circuit current was measured for each differently inclined angle. As a result of the experiment, shown in an regression formula is a relation between the temperature conversion value of the maximum output of the solar cell at the standard temperature of 25{degree}C and the quantity of solar radiation on the inclined surface. Consequently, it enabled the prediction of a charging quantity, in the case of running a small vehicle with solar cells installed, from the quantity of solar radiation on the inclined surface in the clear weather. 2 refs., 4 figs., 2 tabs.

  8. Indirect solar-pumped laser diode using a solar cell; Taiyo denchi wo mochiita taiyoko kansetsu reikigata handotai laser no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kanamori, Y.; Yugami, H.; Naito, H.; Arashi, H. [Tohoku University, Sendai (Japan). Faculty of Engineering

    1996-10-27

    This paper describes the operating characteristics of a stabilizing circuit using commercial electricity, those of a stabilizing circuit using solar cells, relation between the quantity of solar radiation and the maximum output of a semiconductor laser diode (LD), and simulation results of annual LD output in Sendai City. The stabilizing circuit for the solar-cell driven LD was structured such that the output of the solar cell panels was guided to a DC/DC converter, that the voltage was set at a prescribed value and that the current was stabilized with the use of power MOSFET. The solar cells used in the experiment were monocrystal silicone solar cells with the maximum output of 53W each. In the experiment, the LD was protected by stabilizing the current at a set value when an excess current was supplied to the stabilizing circuit. As a result of the simulation of the annual LD output from the meteorological data of Sendai City, it was predicted that a solar cell of approximately 1kW was able to provide an annual output of 102MJ and that the efficiency was highest with four sheets of the solar cell. Consequently, consistency proved to be essential between the LD and the solar cell output. 3 refs., 7 figs.

  9. Manufacture method of CuInSe sub 2 solar cell. CuInSe sub 2 taiyo denchi no seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Y. (Fuji Electric Co. Ltd., Tokyo (Japan))

    1992-04-28

    Energy conversion efficiency of CdS/CuInSe{sub 2} solar cell is very sensitive to a ratio of Cu/In composition and its control is important on manufacture of the cell. The invention aims to provide a CuInSe{sub 2} thin film solar cell and its manufacture method to give a prescribed Cu/In compositional ratio precisely and to enable production of large area cell and low cost. The invention concerns a manufacture method of a CuInSe{sub 2} solar cell, in which Cu-In alloy foil with a prescribed ratio of Cu/In composition is prepared and pressed onto the electrode film on the substrate surface to form a alloy film with a prescribed thickness, on which selenium is deposited from vapor and heated to form a CuInSe{sub 2} film. CdS is stacked on the CuInSe{sub 2} film to form a photovoltaic conversion layer and to afford a CdS/CuInSe{sub 2} solar cell. Zinc oxide may be stacked on the above CdS film and a film made of a transparent conductive material is stacked on the zinc oxide layer to give a solar cell. The invention also includes a manufacturing method in which ZnCdS film is formed on the CuInSe{sub 2} film prepared by the above method. 3 figs.

  10. Solar cells and thin film LED using amorphous SiC. Amorphous SiC wo mochiita taiyou denchi oyobi usumaku LED

    Energy Technology Data Exchange (ETDEWEB)

    Hamakawa, Y. (Osaka Univ., Osaka (Japan). Faculty of Engineering Science)

    1990-03-25

    This paper introduced the photoelectric properties of amorphous SiC (a-SiC), application to highly efficient solar cells, application to wide area emitting elements such as LED (light emitting diode) and application to OEIC (optoelectronic integrated circuit) which is expected in near future. The light sensitizing effect in which photoconductivity of a-SiC:H film increases 2-3 figures by B dopping, was found. Flexible and wide area thin film LED has been able to manufacture by this discovery. In addition, highly efficient conversion rate has been able to get by the technical development such as solar cells made of a-SiC/ a-Si hetrojunction. Further, wide area sollar cells has been able to manufacture on any substrate by the development of TFLED (thin film light emitting diode). The application of TFLED made of SiC to OEIC is also investigated. 18 refs., 15 figs., 2 tabs.

  11. Development of measurement device for evaluation of solar cell module output. 2; Taiyo denchi module shutsuryoku hyokayo sokuteiki no kaihatsu. 2

    Energy Technology Data Exchange (ETDEWEB)

    Minoda, M.; Itsumi, J. [Kumamoto Institute of Technology, Kumamoto (Japan)

    1996-10-27

    Enhancement in design efficiency may be attained as well as utilization in maintenance if on-the-spot data is made available, for the purpose of flexibly dealing with changes in design or matching with a house structure, in calculating the power generation output of a solar cell (PV) module. Under the circumstances, a small-sized compound measuring device was produced as a prototype which, using an I-V curve tracer, measured output and condition of a roof at the time of installation, compared with the optimum operation and predicted the power generation. The device was structured with the main body consisting of a computing part, measurement controller and power supply and with various sensor modules. The electron load control method was employed in order to measure I-V characteristics of the PV module, since it was desirable to use a variable load and to cover the range from the release voltage of a solar cell to the short-circuit state through the maximum output point. The reference module method was used for the system evaluation. The device was presumably applicable to a PV system design by incorporating a sensor module for measuring design environment data, which was essential at the time of a system design, in addition to those for measuring output. 9 refs., 4 figs., 3 tabs.

  12. Control method for light deterioration of amorphous solar cell. Temperature effect method; Amorphous taiyo denchi no hikari rekka yokuseiho. Ondo kokaho

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, H.; Yokoyama, S.; Itsumi, J. [Kumamoto Institute of Technology, Kumamoto (Japan)

    1996-10-27

    This paper describes a proposed method for suppressing light deterioration (temperature effect method), in which an annealing effect was always expected by laminating an NEM element and a heat insulation material on the back side of a-Si solar cell module and thereby raising the temperature in the back side of the module, and also describes an outdoor exposure test device completed for the method. The NEM element consisted of conductive potassium titanate and high molecular polymer and was a self temperature-controlling organic exothermic body that required no outside temperature control device. It was provided with a heat generating temperature of 45-75{degree}C as the exothermic property of the element and capable of generating heating temperature arbitrarily according to the purpose. The NEM element varied a resistance value against the ambient temperature and kept the element temperature constant. Measurement was commenced starting April 19, 1996, using the completed outdoor exposure test device and a measuring circuit. The deterioration phenomenon was and from then on continuously examined under the following conditions: (1) measurements were those of clear days only, and (2) measurements to be used were those between 10:00 and 14:00 with the quantity of solar radiation on a constant level. 4 refs., 4 figs., 1 tab.

  13. Report on commissioned business for fiscal 1997. Development of new power storage system for cells and development of technology for distributed power storage (research for a zinc/air cell system for automobiles); 1997 nendo itaku gyomu hokokusho. Shingata denchi denryoku chozo system kaihatsu bunsangata denryoku chozo gijutsu kaihatsu (denki jidoshayo aen kuki denchi system chosa)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Concerning the above, it is discussed whether such a system is feasible in Japan. A zinc/air cell system requires some special plants for zinc regeneration, etc. It is necessary to build a zinc refining plant and to install dozens of electrode replacing facilities in an area dozens of kilometers in diameter with the plant at the center. For such a system to be functional, there have to be several tens of thousands of automobile users in a limited area. In Japan, so large a number will not be found anywhere even if the appeal is directed to those in the postal service and electric utilities. There will be no economic success in Japan, different from in Germany. As for the economic comparison between a zinc/air cell system and natural gas system, the two will be equivalent to each other as far as the use of the quick filling stations for the natural gas automobiles remains as it is. When the number in consideration is so large as several tens of thousands, however, the natural gas system will turn out to be economically superior to the zinc/air cell system. 19 figs., 29 tabs.

  14. Achievement report for fiscal 1997. Technological development for practical application of a solar energy power generation system/development of technology to manufacture thin film solar cells (development of technology to manufacture applied type thin film solar cells with new construction) (development of technology to manufacture micro light collection type solar cells); 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu, oyogata shinkozo usumaku taiyo denchi no seizo gijutsu kaihatsu (micro shukogata taiyo denchi no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    These technological developments are intended to demonstrate module efficiency of a micro light collection type solar cell of 15% by fiscal 2000, and obtain prospect on the module manufacturing cost of 140 yen per watt. Discussions given during fiscal 1997 are as follows: development has been performed on a design method to decide construction of a non-tracking micro light collection type module; in the state of cells being integrated on the module, the cells are arranged minutely and discretely, whereas, with discussions on a method to form them and assessment of the optical system as the main objective, single crystal silicon solar cells with a size smaller than 5 mm were fabricated on a trial basis; problems of forming micro cells by using the wafer cutting process were clarified; micro cells operating on light collection were fabricated trially to extract technological problems in light collecting operation and discuss technical problems in mass production; and development was performed on an evaluation method to analyze the cells' light collecting operation, and discussions were given on a method to estimate power generation amount from the light collection type modules. (NEDO)

  15. Development of technology of the practical use of the photovoltaic power generation system. ; Studies on the practical use of new type solar cells (studies on the manufacturing technology of layer built solar cells (manufacturing technology of amorphous/compound layer cells)). Taiyoko hatsuden system jitsuyoka gijutsu kaihatsu. ; Shingata taiyo denchi no jitsuyoka kenkyu (sekisogata taiyo denchi seizo gijutsu no jitsuyoka kenkyu (amorphous/kagobutsu sekiso cell seizo gijutsu))

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-01

    To develop the layer built solar cell combined the amorphous silicon with the compound semi-conductor of which conversion efficiency is over 13%, its structure and the techniques to paint the large area are studied. In the a-Si pseudo-cell integrated patterning, the bottom cell power is higher when it is placed parallel. The reliability test of the module of CdS/CdTe cell is done, result of this test shows that the performance does not change after 2400 h. By raising CdTe firing temperature and thinning porous layer, the conversion efficiency is 11.3% in 1.07 cm{sup 2} CdS/CdTe cell. By examining the screen printing in 10 cm{sup 2} substrate, the conversion efficiency is 6.7% when the optimum CdS width is 2.95mm. The forming experiment by the painting machine is done. As the result of this, CdS film is smoother than by screen printing and the conversion efficiency does not change. As the cell becomes largeer the firing case is improved to reduce the temperature difference in the substrate to 31 centigrade. The sub module which is 30*40cm{sup 2}is designed and manufactured, its conversion efficiency is 6.2%. 7 figs., 1 tabs.

  16. 28th Solar Energy Promotion Committee Meeting - 3rd Solar Cell Liaison Meeting. Report for fiscal 1990; Dai 28 kai taiyo energy suishin iinkai dai 3 kai taiyo denchi renrakukai. 1980 nendo hokoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-05-14

    The above events took place in Tokyo in the period May 14-17, 1991, when a total of 89 essays were presented. In relation with the thin film/a-Si systems, 55 presentations were given, which were 'Novel preparation technique termed Chemical Annealing for making a-Si:H with a rigid and stable Si-network,' 'Interface characteristics of a-Si:H films prepared by VHF (very high frequency) plasma CVD (chemical vapor deposition),' 'Preparation of amorphous superlattices by continuous method and characterization of the interface,' etc. In relation with the thin film/compound systems, 8 presentations were given, which were 'Preparation of CuInSe{sub 2} solar cells by selenization method,' 'Deposition of CuInSe{sub 2} films by ICB (ionized cluster beam) technique and their optical characterization,' 'Large-area CdS/CdTe solar cells,' etc. In relation with the crystal/compound systems, 8 presentations were given, which were 'Lattice strain relaxation processes in GaAs grown on Si,' 'Optical transmission studies of tandem solar cells,' etc. In relation with the crystal/Si systems, 18 presentations were given, which were 'Effect of electric field on effective minority carrier lifetime,' 'Computer analysis of surface recombination velocity for high efficiency crystalline silicon solar cells,' etc. (NEDO)

  17. Fiscal 1994 New Sunshine Program achievement report. Development of photovoltaic power generation system practicalization technology - Research on practicalization of thin-film solar cell manufacturing technology (Technology for higher quality - Development of CuInSe{sub 2} solar cell manufacturing technology); 1994 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu (kohinshitsuka gijutsu (CuInSe{sub 2} taiyo denchi seizo no gijutsu kaihatsu))

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The aim is to develop solar cells that exhibit conversion efficiency of 12% in a 10cm times 10cm-large minimodule. When a substrate made of soda lime glass with an SiO{sub 2} coating thereon is used, high reproducibility is achieved in the manufacture of CuInSe{sub 2} (CIS) thin-film solar cells. For the manufacture of a high-quality Cu(InGa)Se{sub 2}(CIGS) light absorbing thin-film layer, it is necessary to develop high-quality precursor film manufacturing and gas phase selenization technologies. A laminated precursor film formed by sputtering is selenized in a H{sub 2}Se gas atmosphere for the formation of CuInSe{sub 2} and CIGS light absorbing thin-film layers, and 16 ZnO/CdS/CIS-structured thin film solar cells built into a 10cm times 10cm-large substrate exhibit conversion efficiency of 11.6%. A CIGS cell using a sulfur-containing Zn compound buffer layer exhibits conversion efficiency of 12.1%. Conditions for the manufacture of a ZnO:Al transparent conductive film are studied. Dependence of CIS-based solar cell output characteristics on temperature and irradiation may be compensated for under the JIS (Japanese Industrial Standard) compensatory formula. The CIS-based thin-film solar cell suffers but a little reduction in output due to temperature rise, and may be therefore said to be excellent. (NEDO)

  18. Changes of the temperature coefficients of the characteristics which accompany degradation and recovery of a-Si solar cells; A-Si taiyo denchi no hikari (denryu) rekka oyobi kaifuku ni tomonau tokusei ondo keisu no henka

    Energy Technology Data Exchange (ETDEWEB)

    Yanagisawa, T.; Koyanagi, T.; Nakamura, K.; Takahisa, K.; Kojima, T. [electrotechnical Laboratory, Tsukuba (Japan)

    1996-10-27

    Pursuant to the measuring of temperature dependency of the characteristics such as conversion efficiency, during the process of degradation in a-Si solar cells due to light and electric current and the process of recovery by annealing, this paper describes changes in temperature coefficients, correlation between the characteristic parameters and the degradation, and the results of the examination of their characteristics. The conversion efficiency {mu} degraded approximately by 45% of the initial value each by the irradiation under a light intensity with 3 SUN accelerated and by the infusion of current at 20mA/cm{sup 2}; and then, the efficiency recovered to 70-75% of the degradation by subsequent annealing. In addition, in the temperature dependency at 80{degree}C against at 20{degree}C, Isc slightly increased while Vcc greatly decreased. This slight increase in Isc was mainly due to the decrease in the width of the forbidden band, while the decrease in Vcc was due to the increase in the reverse saturation current. The temperature dependency of {mu}N was negative, becoming small in accordance with the degradation. The temperature dependency of FF/FFO was negative initially both in light and current, but it decreased with the degradation and turned to positive. The temperature coefficients of I-V parameters reversibly changed corresponding to the degradation and recovery of these parameters and stayed in a good correlation. 7 refs., 8 figs., 1 tab.

  19. Development of solar, fuel, storage, alcoholic, and biomass technologies. (Part 1. Development of coal and geothermal energies). (Part 3. Research and development of industrial technologies); Study on practical application of amorphous solar cell (1). Study on practical application of amorphous solar cell production technology. (Study on practical application of high quality production technology). Taiyo ko hatsuden system jitsuyo ka gijutsu kaihatsu (4); Amorphous taiyo denchi no jitsuyo ka kenkyu (1). Amorphous taiyo denchi seizo gijutsu no jitsuyo ka kenkyu. (ko hinshitsu seizo gijutsu no jitsuyo ka kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    1989-09-01

    The objective of this study is the estabilishment of elemental technologies for high efficient cells by employing tandem structure of compound semiconductor and amorphous silicon/compound semiconductor, and the targets are the cell area of 1 cm{sup 2} and the efficiency of 13% or more. The research and deveopment of tandem structure were carried out using only the a-Si solar cell as the top cell. Computer simulation was adopted for the study of the output of the tandem cell to elucidate the optimum condition. Tandem cell efficiency of 10.69% was achieved by combining with a permeation type a-Si solar cell. The optimization of sintering conditions for improvement was studied to improve the characteristics of CdS/CdTe cell for use as the bottom cell. In the basic studies on CuInSe{sub 2}, monofilm formation technology and juction formation with CdS were investigated. As regards elemental study on common film formation technology, elemental studies on common film formation technology for CdS, CdTe and CIS were performed. 3 figs., 1 tab.

  20. Achievement report for fiscal 1997 on the technological development for practical application of a solar energy power generation system. Development of technology to manufacture ultra-high efficiency crystal compound solar cells; 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu. Chokokoritsu kessho kagobutsu taiyo denchi no seizo gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The present research is intended to develop hetero-epitaxy technology for compound semiconductors on silicon substrates, and hetero-epitaxy technology for grid mismatch between III-V family compound semiconductors, and realize high-efficiency solar cells on silicon substrates. Based on the InP-based etching using a reactive ion etching device, etching conditions suitable for contact layer removal and element separation were obtained. The InP substrate etched under the optimized condition was found etched ideally. Test samples were made, which use a GaAs layer grown at high V/III ratio as the buffer layer, and its effect on crystallization performance was investigated. As a result, it was found that making the V/III ratio high can achieve reduction in defect density and improvement in crystallization performance. A three-stage growth method was used to improve efficiency of GaAs/Si cells, and heat treatment temperature was optimized for an attempt of improving the cell efficiency. It was revealed that rise in the open terminal voltage contributes to improving the cell characteristics at annealing temperatures higher than 950 degrees C or higher, which has been used on a trial basis during this fiscal year. (NEDO)

  1. New Sunshine Program for fiscal 2000. Development of photovoltaic system commercialization technology - Development of thin-film solar cell manufacturing technology - Development of low-cost/large area module manufacturing technology (Development of high-reliability CdTe solar cell module manufacturing technology); 2000 nendo New sunshine keikaku seika hokokusho. Taiyoko hatsuden system jitsuyoka gijutsu kaihatsu, Hakumaku taiyodenchi no seizo gijutsu kaihatsu, Tei cost dai menseki mojuru seizo gijutsu kaihatsu (Koshinraisei CdTe taiyo denchi mojuru no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Research and development was conducted for reliable CdTe solar cell modules, large in area and high in efficiency. In the study of large-area CdS thin film fabrication, a conversion efficiency of 12.5-14.2% was achieved in a cell in a large-area substrate using a mist method-aided process of continuous CdS film fabrication. In the study of large-area CdTe thin film fabrication, the optimization was studied of the base-forming CdS film fabrication conditions and of the CdTe film fabrication conditions in a method using a CdTe powder processed by dry kneading, and a conversion efficiency peak was found to exist when the CdS film thickness was in the range of 700-900 angstrom. In the fabrication of large-area submodules, a large-area substrate was taken up, and TCO (transparent conducting oxide) film was fabricated by the mist method, CdTe film by the normal pressure CSS method, electrodes by the screen printing method, and CdTe film patterns by the blast method. As the result, a conversion efficiency of 11.0% was achieved. In a cost estimation for large-area CdTe solar cell modules, 140 yen/Wp (conversion efficiency: 11.0%, annual production: 100 MW) was obtained. (NEDO)

  2. High efficiency photovoltaic system with LSC. LSC wo mochiita taiyo denchi no kokoritsuka ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Honda, T.; Takazawa, M.; Fujii, T.; Horigome, T. (Tokyo University of Agriculture and Technology, Tokyo (Japan)); Hane, T. (Institute of Technology Shimizu Corporation, Tokyo (Japan)); Maejima, M. (National Science Museum, Tokyo (Japan))

    1990-12-06

    This paper presents a study of the application of Luminescent Solar Concentrator (LSC) conducted in order to increase the conversion efficiency of the photovoltaic system. LSC is a solar concentrator whose structure is very simple, which is a transparent material doped with fluorescent paint. It is already confirmed that the 4 terminal devices which is a conbined LSC and Cds/CdTe solar cells are effective regardless the weather conditions. The output power of CdS/CdTe solar cells with LSC which have some superficial contents were measured experimentally using natural solar radiation as a light source. In the case that LSC {prime} s superficial contents make a slow enlargement, the total conversion efficiency of the cells with LSC decreased. However, if the geometrical condenser percentage of LSC is increased to a level above that of the fixed superficial contents, the total conversion efficiency of the cells with LSC tend to increase. However, because the conversion efficiency decreases accompanied with the size increase of the LSC, it is necessary to improve the ratio of solar concentration by controlling the light distance. 3 refs., 9 figs., 1 tab.

  3. Research report for fiscal 1998. Research into the trends of low-carbon automotive fuel manufacturing technologies; 1998 nendo jidoshayo teitanso nenryo no seizo gijutsu doko chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Studies are made of optimum materials and methods for manufacturing low-carbon fuels for reduction in greenhouse gas emissions. When their thermal dynamic limits and the technological maturity are considered, it is inferred that no extensive improvement will be achieved by merely improving on the efficiency of the existing fuels. The use of various high-efficiency driving power sources utterly different in mechanism from the conventional ones, such as those for fuel cell-powered automobiles, and the promotion of the use of low-carbon fuels such as methanol and methane for all kinds of driving power sources including those for the said fuel cell-powered automobiles, will become necessary. The use will also be necessary of recyclable materials. The biomass resources, in particular, since they absorb CO2 gas in their growing process by virtue of photosynthesis, may be said to be free of CO2 gas emissions. They have their own problems, however, which involve the economy of energy consumed for their production, harvesting, transportation, and conversion into fuels. It is therefore required that their whole life cycle be studied before their greenhouse gas reduction effect may be correctly assessed. The quantities of resources available for the production of automotive low-carbon fuels, manufacturing technologies, etc., are first of all put in order for easy perusal. An effective way is assessed for the whole including the life cycle. (NEDO)

  4. Photovoltaic array capacity determined by considering the environmental factors for load patterns; Fuka pattern ni taisuru kankyo inshi wo koryoshita taiyo denchi array yoryo no kettei

    Energy Technology Data Exchange (ETDEWEB)

    Kameyama, N.; Higuchi, T.; Yamagami, Y.; Tani, T. [Science University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1997-01-30

    Effectiveness of the spectral method was confirmed for system interconnection type photovoltaic (PV) power generation systems, and PV array capacity determined in harmony with the power load was investigated. In this study, system interconnection type PV power generation systems with polycrystalline Si and amorphous Si PV cell modules were discussed. The output electric energy evaluated by the spectral method was compared with that evaluated by the conventional method only considering the cell temperature. Obtained results are as follows. For the polycrystalline Si, the differences between solar supply rates in summer evaluated by the both methods and measured value were less than 2%, which resulted in the accurate determination. For the amorphous Si, however, the difference less than 3% was obtained by the spectral method and that less than 11% was obtained by the conventional method. The spectral method provided higher accuracy. When constructing a system with large array capacity, it was found that the optimum design of PV power generation system can be performed using the spectral method with less array capacity than using the conventional method. 4 refs., 9 figs., 4 tabs.

  5. Studies of flat-plate solar air collectors with absorber plates made of amorphous silicon photovoltaic modules; Amorphous taiyo denchi module wo shunetsuban to shita heibangata kukishiki shunetsuki no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Ito, S.; Miura, N. [Kanagawa Institute of Technology, Kanagawa (Japan)

    1996-10-27

    A light/heat hybrid air type heat collector has been developed in which heat is collected by solar cell panels. In Type 1 heat collector provided with a glass cover, two modules are connected in series and placed under a glass cover to serve as a heat collecting plate, each module built of a steel plate and two thin-film amorphous solar cells bonded to the steel plate. Air runs under the heat collecting plate. Type 2 heat collector is a Type 1 heat collector minus the glass cover. Air is taken in by a fan, runs in a vinyl chloride tube, and then through the heat collector where it is heated by the sun, and goes out at the exit. Heat collecting performance was subjected to theoretical analysis. This heat collector approximated in point of heat collection a model using a board painted black, which means that the new type functions effectively as an air-type heat collector. Operating as a photovoltaic power generator, the covered type generated approximately 20% less than the uncovered type under 800W/m{sup 2} insolation conditions. Type 1 has been in service for five months, and Type 2 for 2 months. At present, both are free of troubles such as deformation and the amorphous solar cell modules have deteriorated but a little. 4 refs., 9 figs.

  6. Study of fuel control strategy based on an fuel behavior model for starting conditions; Nenryo kyodo model ni motozuita shidoji no nenryo hosei hosho ni tsuite no kosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Y.; Uchida, M.; Iwano, H.; Oba, H. [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    We have applied a fuel behavior model to a fuel injection system which we call SOFIS (Sophisticated and Optimized Fuel Injection System) so that we get air/fuel ratio control accuracy and good driveability. However the fuel behavior under starting conditions is still not clear. To meet low emission rules and to get better driveability under starting conditions, better air/fuel ratio control is necessary. Now we have understood the ignition timing, injection timing, and injection pulse width required in such conditions. In former days, we analyzed the state of the air/fuel mixture under cold conditions and made a new fuel behavior model which considered fuel loss such as hydrocarbons and dissolution into oil and so on. Al this time, we have applied this idea to starting. We confirm this new model offers improved air/fuel ratio control. 6 refs., 9 figs., 3 tabs.

  7. Achievement report for fiscal 1998 on area consortium research and development business, 1st year. Area consortium energy research and development (biofuel production by advanced function bioreactor); 1998 nendo chiiki consortium energy bun'ya. Kokino bio reactor ni yoru bio nenryo seisan ni kansuru kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Studies were made to produce ethanol directly from starch and cellulose and to collect biodiesel fuels from waste oil by an enzymatic method. For an increase in the yield of biodiesel fuel production, lipase enzymes were explored and optimum reaction conditions were sought for. Starch decomposition was quick for conversion into the target material in a system with the co-expression of amylase and glucoamylase present on the yeast cell surface layer. There was dramatically rapid progress in the increase of enzymatic activity in the cell, although dependent on cell membrane surface treatment conditions. In the generation of acetaminophen by recombinant cohesive yeasts, highly active and expressive yeasts were automatically fixed in the porous support (intelligent bioreactor) while those deactivated or dead were automatically removed. For the construction of a fuzzy control system for this reaction, basic models were investigated, built on the basis of the enzymatic model of reaction and substance balance. A high-precision structural analysis was conducted for the exploration of secondary structure stabilizing factors in protein and peptide and for the elucidation of correlations between structure and function. (NEDO)

  8. Improvement of the efficiency characteristics on the photovoltaic generation system based on a generation control circuit. Part 3. Research on architectural systematization of energy conversion devices; Dosaten seigyo kairo wo mochiita taiyo denchi hatsuden koritsu no kaizen. 3. Energy henkan no kenchiku system ka ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, T.; Ito, N.; Kimura, G.; Fukao, S.; Sunaga, N.; Tsunoda, M.; Muro, K. [Tokyo Metropolitan University, Tokyo (Japan)

    1996-10-27

    In introducing a photovoltaic power generation system to urban homes, the general practice is to install a large number of solar cell panels on the roof. However, as is often the case, a part of the solar cell panels is in the shadows (partial shadows) of neighboring homes, electric poles, cables and trees. Under the circumstances, studies were made on the numerous changes in the lowered generating capacity of individual solar cells by the partial shadows. Developed by the authors were the generation point control principle, in which the generation point was individually controlled on serially connected plural solar cell modules, and a practical circuit system based on that principle with the effects verified in a field test. In the test, the generated power of the system was 476W without partial shadows, and was 323W with partial shadows and without the operation of the generation point control circuit, increasing to 406W with partial shadows and with the operation of the circuit. As a result, compared with the case where no generation point control circuit was employed, the effectiveness of the proposed circuit was evident. 3 refs., 10 figs., 1 tab.

  9. Achievement report for fiscal 1997 on the development of technologies for utilizing biological resources such as complex biosystems. Development of technologies for producing substitute fuel for petroleum by utilizing organisms; 1997 nendo fukugo seibutsukei nado seibutsu shigen riyo gijutsu kaihatsu seika hokokusho. Seibutsu riyo sekiyu daitai nenryo seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Technologies of producing useful substances using the substance decomposing/producing functions of complex biosystems and methods of their handling are developed. In the utilization of microbes in the digestive tracts of termites and longicorns, it is made clear that several kinds of termites cleave the {beta}-O-4 ether linkage. In relation to technologies for wood decomposing complex microbial system construction and complex vector system development, a screening system is constructed in which strains that exhibit complex actions are combined. Concerning the advanced utilization of tropical oil plants, conditions are determined for inducing callus out of oil palm tissues. Out of oil palm sarcocarp tissues, mRNA (messenger ribonucleic acid) is isolated for the construction of a cDNA (complementary deoxyribonucleic acid) library. For the purpose of isolating a powerful promoter, a partial base sequence is determined for ubiquitin that frequently expresses itself in cells. A pathogenic bacterium ailing the oil palm is sampled for identification, and it is inferred that the bacterium is a kind of Ganoderma boninense. (NEDO)

  10. FY 1997 report on the results of the industrial technology R and D project. Development of technology to use biological resources such as the complex biological system (Development of biological use petroleum substitution fuel production technology); 1997 nendo fukugo seibutsukei nado seibutsu shigen riyo gijutsu kaihatsu seika hokokusho. Seibutsu riyo sekiyu daitai nenryo seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Experimental researches were conducted and the FY 1997 results were reported with the aim of establishing analytical technology for the complex biological system by which the complex biological system can be analyzed in such a state as it is using the molecular biological method. In the study of the molecular genetic analytical technology, PCR primers used for amplification of topoisomerase II genes of the whole eukaryote was designed. As to the histochemical analytical technology, a study was made on the new constitution microorganism detection method by the hybridization method and the antibody specific dyeing method, and the following were conducted: manifestation in quantity of colibacillus and the recovery, refining, and construction of peptide library by fuzzy display method. Concerning the functional analytical technology, technological researches were made such as the environmental adaptation mechanism of high thermophile and the information transfer mechanism among bacteria through cell membranes for elucidation of the special environment detection/response mechanism and the special environment adaptation/resistance mechanism. As to the separation/culture technology, various anaerobic microorganisms were separated from marine sponge for the development of a method of culturing in 3D matrices. (NEDO)

  11. Method for estimation of the output electric power of PV module with considering environmental factors. Method for estimation of output using I-V curves; Kankyo inshi wo koryoshita taiyo denchi module no shutsuryoku keisanho. I-V tokusei curve ni yoru keisan

    Energy Technology Data Exchange (ETDEWEB)

    Yamagami, Y.; Tani, T. [Science University of Tokyo, Tokyo (Japan)

    1996-10-27

    Based on the basic quality equation of photovoltaic (PV) cell, a quality equation of PV module has been constructed by considering the spectral distribution of solar radiation and its intensity. A calculation method has been also proposed for determining the output from current-voltage (I-V) curves. Effectiveness of this method was examined by comparing calculated results and observed results. Amorphous Si (a-Si) and polycrystal Si PV modules were examined. By considering the environmental factors, differences of the annual output between the calculated and observed values were reduced from 2.50% to 0.95% for the a-Si PV module, and from 2.52% to 1.24% for the polycrystal Si PV module, which resulted in the reduction more than 50%. For the a-Si PV module, the environmental factor most greatly affecting the annual output was the spectral distribution of solar radiation, which was 3.86 times as large as the cell temperature, and 1.04 times as large as the intensity of solar radiation. For the polycrystal PV module, the environmental factor most greatly affecting the annual output was the cell temperature, which was 7.05 times as large as the spectral distribution of solar radiation, and 1.74 times as large as the intensity of solar radiation. 6 refs., 4 figs., 1 tab.

  12. Research on natural gas fuel injection system. Development of high-performance pressure regulator; Tennen gas yo nenryo funsha system no kenkyu kaihatsu. 1. Tennen gas nenryo funshayo no koseino regulator kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kato, S.; Ishii, M.; Takigawa, B.; Makabe, K.; Harada, S.; Ono, H. [Nippon Carburetor Co. Ltd., Tokyo (Japan)

    1997-10-01

    With the aim of further reducing the exhaust emissions of natural-gas vehicles, vigorous research and development work is under way today on multi point gas injection (MPGI) system. In this studies, a high-performance pressure regulator, which is one of the main components of this MPGI system, has been newly developed. The results showed that a significantly better accuracy of the regulated pressure level using this regulator was obtained under the wide range of operating conditions, including instantaneously greater changes of fuel flow rate. In addition, the advanced studies of gaseous fuel injectors (GFIs) would be also conducted. 4 refs., 8 figs.

  13. Upgrading of brown coal by slurry-dewatering; Kattan no yuchu dassui ni yoru clean kotai nenryo no seizo

    Energy Technology Data Exchange (ETDEWEB)

    Okuma, O.; Shimizu, T.; Inoue, T.; Shigehisa, T.; Deguchi, T.; Katsushima, S. [Kobe Steel, Ltd., Kobe (Japan)

    1996-10-28

    This paper describes an outline of solid fuel production process from brown coal and the investigation results of its elemental techniques. Dried coal is produced by this process which consists of a dewatering of crushed brown coal in oil-based solvent, a solid and liquid separation of slurry, and a remained oil recovery by heating. This process is characterized by the higher thermal efficiency compared with usual drying and the restraint of spontaneous combustion of product coal. It was revealed that solid fuel with low moisture, low ash, low sulfur, and suppressed spontaneous combustion property can be produced from Australian brown coal through this process. From the comparison between kerosene and fuel oil A, it was confirmed that the oil content during dewatering was smaller and the oil recovery by heating was easier by using a solvent with lower boiling point. It was also confirmed that the spontaneous combustion property can be suppressed using small amount of asphalt by solving asphalt in the solvent and adsorbing asphalt on the surface of brown coal. From these results, low rank coals including brown coal, which are difficult to use, are expected to be used as clean coal with low ash and low sulfur through this process. 2 refs., 7 figs., 2 tabs.

  14. Analysis of fuel spray characteristics for premixed lean diesel combustion; Kihaku yokongo diesel kikan ni okeru nenryo funmu kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, S.; Harada, a.; Miyamoto, T.; Akagawa, H.; Tsujimura, K.

    1997-10-01

    Premixed lean diesel combustion (PREDIC) makes it possible to achieve low NOx emission. It is an important factor to make the homogeneous spray formation for PREDIC. In this paper presents I the effect of the spray dispersion on emission characteristic were analyzed with the spray observation and engine test. Pintle type nozzle, which has different feature from orifice type nozzle, are used to form the hollow cone spray. As a result, the pintle type nozzle having grooves to generate the swirl flow, makes the reduced penetration in comparison with the hole nozzle under low ambient gas pressure. And it could improve THC, CO emissions at low NOx emission condition. 7 refs., 12 figs., 1 tab.

  15. Stem Cells

    Science.gov (United States)

    Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  16. Visualization of sooting field in an emulsion droplet flame by using microgravity environment; Bisho juryoku kankyo wo riyoshita nyuka nenryo ekiteki kaennai susu nodoba no kashika

    Energy Technology Data Exchange (ETDEWEB)

    Segawa, D.; Kadota, T. [University of Osaka Prefecture, Osaka (Japan). Faculty of Engineering; Tsue, M.; Kono, M. [The University of Tokyo, Tokyo (Japan); Yamasaki, H. [Ehime Univ., Ehime (Japan). Faculty of Education

    1999-07-25

    Sooting field in a flame formed around a suspended droplet was visualized under microgravity using the planar laser light scattering technique. The soot concentration and the instantaneous soot amount were approximately estimated from the intensity of the scattered light using the image analysis system. The fuels employed were water-in-oil emulsions composed of n-dodecane, water and surfactant. The water content was varied from 0 to 0.2 in volume. A soot layer which was concentric with the droplet was observed inside the luminous flame. The results show the unsteadiness of the sooting behavior as well as the flame behavior. The maximum of the soot concentration is located near the inner edge of the soot layer. The time history of the instantaneous soot amount is similar to that of the instantaneous flame radius. The maximum of the soot concentration does not vary with the water content, while the soot amount decreases significantly with the water emulsification. (author)

  17. Ignition and combustion of solid-particle mixed fuel drop in a microgravity environment; Bisho juryokuka ni okeru kotai ryushi konnyu nenryo ekiteki no chakka to nensho

    Energy Technology Data Exchange (ETDEWEB)

    Tanishige, R. [Zexel Corp., Tokyo (Japan); Shimoguchi, T. [Mitsubishi Agricultural Machinery Co. Ltd., Tokyo (Japan); Yoshizaki, T. [Hiroshima University, Hiroshima (Japan); Hiroyasu, H. [Kinki University, Osaka (Japan); Sakuraya, T. [Japan Space Utilization Promotion Center, Tokyo (Japan)

    1998-10-20

    The ignition and combustion behavior of single Mg slurry and pure C slurry fuel drops were observed at higher temperature under microgravity condition, and compared with those under normal gravity condition. As a result, the lowest ignition temperature of primary flame in liquid fuel combustion under microgravity is lower than that under normal gravity. Solid combustion (secondary combustion) characteristics of slurry fuel drops under microgravity are unaffected by the kind of liquid fuels, however, primary flame ignition delay of slurry fuel drops using cetane is larger than that using dodecane. Under microgravity, soot particle layers are observed on flame surfaces after expansion and contraction of spherical flame during a primary flame period. The layer density is larger in pure C slurry than another slurry. In particular, a primary flame expansion ratio of pure C slurry fuel drops increases stepwise with ambient temperature in a temperature range over the lowest ignition temperature of solid combustion. 8 refs., 18 figs., 3 tabs.

  18. Ignition and combustion of a coal-oil mixture drop in a microgravity environment; Bisho juryokuka ni okeru COM nenryo ekiteki no chakka to nensho

    Energy Technology Data Exchange (ETDEWEB)

    Tanishige, R.; Yoshizaki, T.; Hiroyasu, H. [Hiroshima University, Hiroshima (Japan); Sakuraya, T. [Japan Space Utilization Promotion Center, Tokyo (Japan)

    1996-12-20

    Slurry drops made of coal-oil mixture (COM) were ignited and burned at the underground gravity-free experiment center to investigate their characteristics. The experiment was purposed to analyze vapor combustion in a location removed of influence from natural convection and forced convection, and compare it with combustion behavior under normal gravity. The following findings were obtained: the primary flame swells and contracts after ignition, swells again making the flame diameter maximum, and then contracts again to form a second-stage fuel flame; ignition delays when ambient temperature is low, and the second-stage flame occurs in a high temperature region; the primary flame under micro gravity is generated in a lower temperature zone than that under the normal gravity, and the primary flame period is extended longer; COM drop ignition under micro gravity requires smaller activation energy; generation of soot husks centering around the drops becomes remarkable as brightness of spherical flame decreases; the ignition started at 589 K against 970 K for ignition under the normal gravity; liquid components evaporated before ignition are distributed spherically symmetrically around drops; and there is no air flow to have the components scattered and lost. 12 refs., 8 figs., 2 tabs.

  19. Effects of fuel and air mixing on WOT output in direct injection gasoline engine; Chokufun gasoline kikan ni okeru nenryo to kuki no kongo to shutsuryoku seino

    Energy Technology Data Exchange (ETDEWEB)

    Noda, T.; Iriya, Y.; Naito, K.; Mitsumoto, H.; Iiyama, A. [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    The effects of in-cylinder charge motion and the characteristics of the fuel spray and piston crown shape on WOT output in a direct injection gasoline engine are investigated. The fuel and air mixing process in a cylinder is analyzed by computer simulation and LIF method visualization. As a result, the technical factors to achieve enough mixing in a DI gasoline engine equipped with bowl in piston optimized for stratified combustion are clarified. 7 refs., 9 figs., 1 tab.

  20. Effect of fuel composition on poly aromatic hydrocarbons in particulate matter from DI diesel engine; Particulate chu no PAH ni oyobosu nenryo sosei no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, S.; Tatani, T.; Yoshida, H.; Takizawa, H.; Miyoshi, K.; Ikebe, H. [COSMO Research Institute, Tokyo (Japan)

    1997-10-01

    The effect of fuel composition on poly aromatic hydrocarbons (PAH) in particulate matter from DI diesel engine was investigated by using deeply desulfurized fuel and model fuel which properties are not interrelated. It was found that the deeply desulfurized fuel have effect on reducing PAH emissions. Furthermore, it was suggested that poly aromatics in the fuel affect PAH emissions and the influence of tri-aromatics in the fuel was promoted by the coexistence of mono-aromatics or naphthene. PAH formation scheme from each fuel component was proposed by chemical thermodynamic data. 4 refs., 8 figs., 3 tabs.

  1. Numerical simulation of fuel sprays and combustion in a premixed lean diesel engine; Kihaku yokongo diesel kikan ni okeru nenryo funmu to nensho no suchi simulation

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, T.; Harada, A.; Sasaki, S.; Shimazaki, N.; Hashizume, T.; Akagawa, H.; Tsujimura, K.

    1997-10-01

    Fuel sprays and combustion in a direct injection Premixed lean Diesel Combustion (PREDIC) engine, which can make smokeless combustion with little NOx emission, is studied numerically. Numerical simulation was carried out by means of KIVA II based computer code with a combustion submodel. The combustion submodel describes the formation of combustible fuel vapor by turbulent mixing and four-step chemical reaction which includes low temperature oxidation. Comparison between computation and experiment shows qualitatively good agreement in terms of heat release rate and NO emission. Computational results indicate that the combustion is significantly influenced by fuel spray characteristics and injection timing to vary NO emission. 10 refs., 8 figs., 1 tab.

  2. Cavitation characteristics of multihole diesel-fuel nozzles in high-speed oil flows. Diesel kikan yo nenryo tako nozzle no abura cavitation tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Yokota, M. (Shimonoseki Univ. of Fisheris, Yamaguchi (Japan)); Ito, Y. (Hachinohe Inst. of Tech., Aomori (Japan)); Aoki, H. (Xexel-Gleason U.S.A. Inc., New York (U.S.A))

    1991-07-25

    Recently, since higher velocity and higher pressure are required for diesel injection systems, cavitation behaviors in high velocity oil flows are strongly interested in such as 100 to 500 m/s for oil flow velocity and less than the cavitation factor {sigma} of 0.01. In this paper, oil cavitation characteristics at the injection part of multihole nozzles, especially on the flow characteristics, were studied systematically using fuel injection multihole nozzles for an actual use. As a result, it was clarified that subcavitation area (sub C), transition area, and supercavitation area (SC) could be existing in C{sub d}-{sigma} relation, which was similar to that specified cavitation conditions could be exisiting in the actual working area of multihole nozzles. And it was also clarified that flow coefficient C{sub d} relied on Reynolds number R{sub e} in the transition of {sigma}{ge}{sigma}{sub cr} and in {sub C} area, and mainly relied on {sigma} in SC area of {sigma}<{sigma}{sub cr}. Moreover, it was also confirmed that such tendency was similar to the one of the two-dimensional contraction of an area. 22 refs., 10 figs., 1 tab.

  3. Improvement of lean combustion characteristics of heavy-hydrocarbon fuels with hydrogen addition; Suiso tenka ni yoru kokyu tanka suisokei nenryo no kihaku nensho no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Y. [Saitama Institute of Technology, Saitama (Japan); Ishizuka, S. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

    1999-09-25

    The Lewis numbers of lean heavy-hydrocarbon fuels are larger than unity, and hence, their flames are prone to extinction in a shear flow, which occurs in a turbulent combustion. Here, propane is used as a representative fuel of heavy-hydrocarbon fuels because the Lewis number of lean propane/air mixtures is larger than unity, and an attempt to improve its combustion characteristics by hydrogen addition has been made. A tubular flame burner is used to evaluate its improvement, since a rotating, stretched vortex flow is established in the burner. The results show that with' hydrogen addition, the fuel concentration, the flame diameter and the flame temperature at extinction are reduced and its combustion characteristics are improved. However, it is found that the effective equivalence ration at extinction cannot become so small as that of lean methane/air mixture, which has a Lewis number less than unity. (author)

  4. T Cells

    Science.gov (United States)

    T Cells - National Multiple Sclerosis Society Skip to navigation Skip to content Menu Navigation National Multiple Sclerosis Society Sign ... Is MS? Definition of MS T Cells T Cells Share Smaller Text Larger Text Print In this ...

  5. Cell counting.

    Science.gov (United States)

    Phelan, M C; Lawler, G

    2001-05-01

    This unit presents protocols for counting cells using either a hemacytometer or electronically using a Coulter counter. Cell counting with a hemacytometer permits effective discrimination of live from dead cells using trypan blue exclusion. In addition, the procedure is less subject to errors arising from cell clumping or size heterogeneity. Counting cells is more quickly and easily performed using an electronic counter, but live-dead discrimination is unreliable. Cell populations containing large numbers of dead cells and/or cell clumps are difficult to count accurately. In addition, electronic counting requires resetting of the instrument for cell populations of different sizes; heterogeneous populations can give rise to inaccurate counts, and resting and activated cells may require counting at separate settings. In general, electronic cell counting is best performed on fresh peripheral blood cells. PMID:18770655

  6. Effect of PV module output power on module temperature; Taiyo denchi no shutsuryoku henka ga module hyomen ondo ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Hongo, T.; Kitamura, A. [Kansai Electric Power Co. Inc., Osaka (Japan); Igaki, K.; Mizumoto, T. [Kanden Kako Co. Inc., Osaka (Japan)

    1996-10-27

    Effect of the photovoltaic (PV) module output power variation on the module surface temperature has been investigated by field measurements. PV modules with capacity of 54 W were used for the temperature measurements. Three 2 kW-class PV systems were operated. T-type thermocouples were used for measuring temperatures. Measurement time intervals were 15 minutes, 30 minutes, 60 minutes, and 24 hours. Measurement period was between May 25, 1995 and June 25, 1996. The surface temperature increased during non-loaded PV output, and decreased during load-carrying PV output. Difference of the surface temperature between non-loaded PV output and load-carrying PV output was 3.5{degree}C at maximum through a year. The surface temperature was saturated within 30 minutes. When PV output was changed in 30 or 60 minutes interval, the variation of surface temperature was distinctly observed. When PV output was changed in 15 minutes interval, it was not observed distinctly. There was no difference of the surface temperatures during the time zones with less solar radiation, such as in the morning and evening, and at night. Except these time zones, difference of the surface temperatures was 3.5{degree}C at maximum. 4 figs.

  7. Sony Co., Ltd.: An outlook is made for merchandising of the manganese acid lithium ion battery; Mangansan richiumuion denchi no shohinka ni medo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    Sony Co., Ltd. sells the manganese acid lithium ion battery that a battery is 1 by 2 as to the next generation lithium ion during 99 years. It is characteristics that a price is restrained because manganese is used for the proper pole material instead of cobalt of the rare metal. It becomes mass production by Koriyama factory where a lithium ion battery is being manufactured improving an existent production line. It is seen when some percents of manufacture cost goes down more than cobalt acid battery of news file before. A manganese acid lithium ion battery uses manganese acid lithium for the proper pole of the battery. The efficiency of the charge of the usual lithium ion battery is good, and composition is easy, and uses cobalt acid lithium, which is easy to produce. One side where a material fee is cheap, the stability at the high temperature of manganese acid is low, and composition is difficult. Only NEC Moli Energy corporation who is the subsidiary company of NEC succeeds in the mass production. NEC Moli Energy corporation is extending market share by the price competition power. It seems to have the possibility that manganese acid becomes the main force with a battery by two by new entering of Sony Co., Ltd. of the lithium ion battery extreme big enterprises. (translated by NEDO)

  8. Study on property-gradient polymer electrolyte for rechargeable lithium batteries; Lithium niji denchi no tame no keisha tokusei kobunshi denkaishitsu no sosei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Kokumi, Z.; Kanemura, S.; Inaba, M.; Takehara, Z.; Yao, K.; Uchimoto, Y. [Kyoto University, Kyoto (Japan)

    1997-02-01

    This paper describes the fundamental experiments for creating property-gradient polymer electrolyte for rechargeable lithium batteries. The rechargeable lithium battery is composed of an anodic composite agent section with high ion conductivity, a separator equivalent section with high mechanical strength (high bridging degree), and a section surpressing the precipitation of metal lithium by contacting with it. The continuous property-gradient polymer electrolyte was tried to be synthesized by means of the plasma polymerization method. As a result, plasma polymerization electrolyte with high ion conductivity could be prepared from the liquid phase by using a monomer with low vapor pressure. Porous material simulating the anodic composite agent was impregnated by the monomer, which was plasma-polymerized. As a result, it was found that the bridging degree decreased from the surface towards the inside of the plasma-polymerized porous material. In addition, polymer was prepared using fluorine-base monomer. Thus, LiF thin film could be prepared through the reaction between the polymer and metal lithium. 3 figs.

  9. Electric discharge performance of electrolytic manganese dioxide relating to key factors in production process. Denkai nisanka mangan no denchi seino ni oyobosu juyo seizo yoin no kento

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, K.; Kumamoto, S.; Hieda, M. (Fukuoka University, Fukuoka (Japan). Faculty of Engineering)

    1994-03-01

    Small scale experiment on production of EMD (electrolytic manganese dioxide) and evaluation on performance of batteries using the EMD were conducted to single out some of the state-of-the-art problems for research subjects in the future. In the experiment, three kinds of anodes were compared, such as graphite, titanium, and a new type of titanium anode having a number of platinum pock-marks mounted on the surface. In the evaluation, electric discharge curves in wet batteries were investigated. The result obtained was as follows: the paraffin layer floated on the high temperature electrolysis bath for preventing the electrolyte vaporization little affects the performance of the EMD obtained with the ordinary titanium anode, but adversely affects the performance in the case of the EMD produced with the graphite anode or the new type titanium anode. Whereas the ordinary titanium anode is passivated under the conditions examined, there is a possibility to lessen the passivation with the new type titanium anode. The neutralization of the EMD deposits is important to control the open-circuit voltage of the battery, but it may be unnecessary in the future. 5 refs., 7 figs.

  10. Galvanic Cells

    Science.gov (United States)

    Young, I. G.

    1973-01-01

    Many standard physical chemistry textbooks contain ambiguities which lead to confusion about standard electrode potentials, calculating cell voltages, and writing reactions for galvanic cells. This article shows how standard electrode potentials can be used to calculate cell voltages and deduce cell reactions. (Author/RH)

  11. Cell Biochips

    Science.gov (United States)

    Pioufle, B. Le; Picollet-D'Hahan, N.

    A cell biochip is a microsystem, equipped with electronic and microfluidic functions, designed to manipulate or analyse living cells. The first publications in this emerging area of research appeared toward the end of the 1980s. In 1989 Washizu described a biochip designed to fuse two cells by electropermeabilisation of the cytoplasmic membrane [1]. Research centers have devised a whole range of cell chip structures, for simultaneous or sequential analysis of single cells, cell groups, or cell tissues reconstituted on the chip. The cells are arranged in a square array on a parallel cell chip for parallel analysis, while they are examined and processed one by one in a microchannel in the case of a series cell chip. In contrast to these biochips for high-throughput analysis of a large number of cells, single-cell chips focus on the analysis of a single isolated cell. As in DNA microarrays, where a large number of oligonucleotides are ordered in a matrix array, parallel cell chips order living cells in a similar way. At each point of the array, the cells can be isolated, provided that the cell type allows this, e.g., blood cells, or cultivated in groups (most adhesion cells can only survive in groups). The aim is to allow massively parallel analysis or processing. Le Pioufle et al. describe a microdevice for the culture of single cells or small groups of cells in a micropit array [2]. Each pit is equipped to stimulate the cell or group of cells either electrically or fluidically. Among the applications envisaged are gene transfer, cell sorting, and screening in pharmacology. A complementary approach, combining the DNA microarray and cell biochip ideas, has been put forward by Bailey et al. [3]. Genes previously arrayed on the chip transfect the cultured cells on the substrate depending on their position in the array (see Fig. 19.1). This way of achieving differential lipofection on a chip was then taken up again by Yoshikawa et al. [4] with primary cells, more

  12. Cell Wall

    OpenAIRE

    Jamet, Elisabeth; Canut, Hervé; Boudart, Georges; Albenne, Cécile; Pont-Lezica, Rafael F

    2008-01-01

    This chapter covers our present knowledge of cell wall proteomics highlighting the distinctive features of cell walls and cell wall proteins in relation to problems encountered for protein extraction, separation and identification. It provides clues to design strategies for efficient cell wall proteomic studies. It gives an overview of the kinds of proteins that have yet been identified: the expected proteins vs the identified proteins. Finally, the new vision of the cell wall proteome, and t...

  13. Stem Cells

    OpenAIRE

    Madhukar Thakur

    2009-01-01

    Objective: The objective of this presentation is to create awareness of stem cell applications in the ISORBE community and to foster a strategy of how the ISORBE community can disseminate information and promote the use of radiolabeled stem cells in biomedical applications. Methods: The continued excitement in Stem Cells, in many branches of basic and applied biomedical science, stems from the remarkable ability of stem cells to divide and develop into different types of cells in ...

  14. Engineering cell-cell signaling.

    Science.gov (United States)

    Blagovic, Katarina; Gong, Emily S; Milano, Daniel F; Natividad, Robert J; Asthagiri, Anand R

    2013-10-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cells (cell surface engineering and synthetic gene circuits) to modulate juxtacrine cell-cell signaling. In addition, significant progress has been made in elucidating design rules and strategies to modulate juxtacrine signaling on the basis of quantitative, engineering analysis of the mechanical and regulatory role of juxtacrine signals in the context of other cues and physical constraints in the microenvironment. These advances in engineering juxtacrine signaling lay a strong foundation for an integrative approach to utilize synthetic cells, advanced 'chassis' and predictive modeling to engineer the form and function of living tissues.

  15. Cell Motility

    CERN Document Server

    Lenz, Peter

    2008-01-01

    Cell motility is a fascinating example of cell behavior which is fundamentally important to a number of biological and pathological processes. It is based on a complex self-organized mechano-chemical machine consisting of cytoskeletal filaments and molecular motors. In general, the cytoskeleton is responsible for the movement of the entire cell and for movements within the cell. The main challenge in the field of cell motility is to develop a complete physical description on how and why cells move. For this purpose new ways of modeling the properties of biological cells have to be found. This long term goal can only be achieved if new experimental techniques are developed to extract physical information from these living systems and if theoretical models are found which bridge the gap between molecular and mesoscopic length scales. Cell Motility gives an authoritative overview of the fundamental biological facts, theoretical models, and current experimental developments in this fascinating area.

  16. Photovoltaic Cells

    Directory of Open Access Journals (Sweden)

    Karolis Kiela

    2012-04-01

    Full Text Available The article deals with an overview of photovoltaic cells that are currently manufactured and those being developed, including one or several p-n junction, organic and dye-sensitized cells using quantum dots. The paper describes the advantages and disadvantages of various photovoltaic cells, identifies the main parameters, explains the main reasons for the losses that may occur in photovoltaic cells and looks at the ways to minimize them.Article in Lithuanian

  17. Solar cells

    Science.gov (United States)

    Cuquel, A.; Roussel, M.

    The physical and electronic characteristics of solar cells are discussed in terms of space applications. The principles underlying the photovoltaic effect are reviewed, including an analytic model for predicting the performance of individual cells and arrays of cells. Attention is given to the effects of electromagnetic and ionizing radiation, micrometeors, thermal and mechanical stresses, pollution and degassing encountered in space. The responses of different types of solar cells to the various performance-degrading agents are examined, with emphasis on techniques for quality assurance in the manufacture and mounting of Si cells.

  18. Engineering Cell-Cell Signaling

    OpenAIRE

    Blagovic, Katarina; Gong, Emily S.; Milano, Daniel F.; Natividad, Robert J.; Asthagiri, Anand R

    2013-01-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cel...

  19. Stem Cells

    Directory of Open Access Journals (Sweden)

    Madhukar Thakur

    2015-02-01

    Full Text Available Objective: The objective of this presentation is to create awareness of stem cell applications in the ISORBE community and to foster a strategy of how the ISORBE community can disseminate information and promote the use of radiolabeled stem cells in biomedical applications. Methods: The continued excitement in Stem Cells, in many branches of basic and applied biomedical science, stems from the remarkable ability of stem cells to divide and develop into different types of cells in the body. Often called as Magic Seeds, stem cells are produced in bone marrow and circulate in blood, albeit at a relatively low concentration. These virtues together with the ability of stem cells to grow in tissue culture have paved the way for their applications to generate new and healthy tissues and to replace diseased or injured human organs. Although possibilities of stem cell applications are many, much remains yet to be understood of these remarkable magic seeds. Conclusion: This presentation shall briefly cover the origin of stem cells, the pros and cons of their growth and division, their potential application, and shall outline some examples of the contributions of radiolabeled stem cells, in this rapidly growing branch of biomedical science

  20. Types of Stem Cells

    Science.gov (United States)

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... stem cells blog from the International Society for Stem Cell Research. Learn About Stem Cells From Lab to You ...

  1. Fuel Cells

    DEFF Research Database (Denmark)

    Smith, Anders; Pedersen, Allan Schrøder

    2014-01-01

    Fuel cells have been the subject of intense research and development efforts for the past decades. Even so, the technology has not had its commercial breakthrough yet. This entry gives an overview of the technological challenges and status of fuel cells and discusses the most promising applications...... of the different types of fuel cells. Finally, their role in a future energy supply with a large share of fluctuating sustainable power sources, e.g., solar or wind, is surveyed....

  2. Cell suicide

    International Nuclear Information System (INIS)

    In the fight of the cell against the damages caused to its DNA by genotoxic agents and specially by ionizing radiations, the p53 protein plays a central part. It intervenes in the proliferation control and the differentiation but also in the keeping of genome integrity. It can direct the damages cells toward suicide, or apoptosis, to avoid the risk of tumor appearance that would be fatal to the whole organism. That is by the disordered state of cells suicide programs that the tumor cells are going to develop. The knowledge of apoptosis mechanisms, to eventually start them on demand, rises up broad hopes in the cancer therapy. (N.C.)

  3. Reprogrammed Pluripotent Stem Cells from Somatic Cells

    OpenAIRE

    Kim, Jong Soo; Choi, Hyun Woo; Choi, Sol; Do, Jeong Tae

    2011-01-01

    Pluripotent stem cells, such as embryonic stem (ES) cells, can differentiate into all cell types. So, these cells can be a biological resource for regenerative medicine. However, ES cells known as standard pluripotent cells have problem to be used for cell therapy because of ethical issue of the origin and immune response on the graft. Hence, recently reprogrammed pluripotent cells have been suggested as an alternative source for regenerative medicine. Somatic cells can acquire the ES cell-li...

  4. Fuel Cells

    Science.gov (United States)

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  5. [Cell cultures].

    Science.gov (United States)

    Cipro, Simon; Groh, Tomáš

    2014-01-01

    Cell or tissue cultures (both terms are interchangeable) represent a complex process by which eukaryotic cells are maintained in vitro outside their natural environment. They have a broad usage covering not only scientific field but also diagnostic one since they represent the most important way of monoclonal antibodies production which are used for both diagnostic and therapeutic purposes. Cell cultures are also used as a "cultivation medium" in virology and for establishing proliferating cells in cytodiagnostics. They are well-established and easy-to-handle models in the area of research, e.g. as a precious source of nucleic acids or proteins. This paper briefly summarizes their importance and methods as well as the pitfalls of the cultivation and new trends in this field. PMID:24624984

  6. Fuel cells

    Directory of Open Access Journals (Sweden)

    D. N. Srivastava

    1962-05-01

    Full Text Available The current state of development of fuel cells as potential power sources is reviewed. Applications in special fields with particular reference to military requirements are pointed out.

  7. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  8. Cell sorting by deterministic cell rolling

    OpenAIRE

    Choi, Sungyoung; Karp, Jeffrey M.; Karnik, Rohit

    2011-01-01

    This communication presents the concept of “deterministic cell rolling”, which leverages transient cell-surface molecular interactions that mediate cell rolling to sort cells with high purity and efficiency in a single step.

  9. Electrochemical cell

    Science.gov (United States)

    Nagy, Zoltan; Yonco, Robert M.; You, Hoydoo; Melendres, Carlos A.

    1992-01-01

    An electrochemical cell has a layer-type or sandwich configuration with a Teflon center section that houses working, reference and counter electrodes and defines a relatively narrow electrolyte cavity. The center section is surrounded on both sides with thin Teflon membranes. The membranes are pressed in place by a pair of Teflon inner frames which are in turn supported by a pair of outer metal frames. The pair of inner and outer frames are provided with corresponding, appropriately shaped slits that are in plane generally transverse to the plane of the working electrode and permit X-ray beams to enter and exit the cell through the Teflon membranes that cover the slits so that the interface between the working electrode and the electrolyte within the cell may be analyzed by transmission geometry. In one embodiment, the center section consists of two parts, one on top of the other. Alternatively, the center section of the electrochemical cell may consist of two intersliding pieces or may be made of a single piece of Teflon sheet material. The electrolyte cavity is shaped so that the electrochemical cell can be rotated 90.degree. in either direction while maintaining the working and counter electrodes submerged in the electrolyte.

  10. Solar cells

    Science.gov (United States)

    Treble, F. C.

    1980-11-01

    The history, state of the art, and future prospects of solar cells are reviewed. Solar cells are already competitive in a wide range of low-power applications, and during the 1980's they are expected to become cheaper to run than diesel or gasoline generators, the present mainstay of isolated communities. At this stage they will become attractive for water pumping, irrigation, and rural electrification, particularly in developing countries. With further cost reduction, they may be used to augment grid supplies in domestic, commercial, institutional, and industrial premises. Cost reduction to the stage where photovoltaics becomes economic for large-scale power generation in central stations depends on a technological breakthrough in the development of thin-film cells. DOE aims to reach this goal by 1990, so that by the end of the century about 20% of the estimated annual additions to their electrical generating capacity will be photovoltaic.

  11. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    In his influential essay on markets, An essay on framing and overflowing (1998), Michel Callon writes that `the growing complexity of industrialized societies [is] due in large part to the movements of the technosciences, which are causing connections and interdependencies to proliferate'. This p...... and tantalizing than stem cells, in research, in medicine, or as products.......'. This paper is about tech-noscience, and about the proliferation of connections and interdependencies created by it.More specifically, the paper is about stem cells. Biotechnology in general has the power to capture the imagination. Within the field of biotechnology nothing seems more provocative...

  12. Cell Libraries

    Science.gov (United States)

    1994-01-01

    A NASA contract led to the development of faster and more energy efficient semiconductor materials for digital integrated circuits. Gallium arsenide (GaAs) conducts electrons 4-6 times faster than silicon and uses less power at frequencies above 100-150 megahertz. However, the material is expensive, brittle, fragile and has lacked computer automated engineering tools to solve this problem. Systems & Processes Engineering Corporation (SPEC) developed a series of GaAs cell libraries for cell layout, design rule checking, logic synthesis, placement and routing, simulation and chip assembly. The system is marketed by Compare Design Automation.

  13. Solar cells

    International Nuclear Information System (INIS)

    A method of producing solar cells is described which consists of producing a substantially monocrystalline tubular body of silicon or other suitable semiconductor material, treating this body to form an annular rectifying junction and then cutting it longitudinally to form a number of nearly flat ribbons from which the solar cells are fabricated. The P=N rectifying junction produced by the formation of silicon dioxide on the layers at the inner and outer surfaces of the body can be formed by ion-implantation or diffusion. (U.K.)

  14. Learn About Stem Cells

    Science.gov (United States)

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... ISSCR Get Involved Media © 2015 International Society for Stem Cell Research Terms of Use Disclaimer Privacy Policy

  15. Stem Cell Basics

    Science.gov (United States)

    ... Information Stem Cell Basics Stem Cell Basics: Introduction Stem Cell Information General Information Clinical Trials Funding Information Current Research Policy Glossary Site Map Stem Cell Basics Introduction: What are stem cells, and why ...

  16. Stem Cell Information: Glossary

    Science.gov (United States)

    ... Neurons Oligodendrocyte Parthenogenesis Passage Pluripotent Polar body Preimplantation Proliferation Regenerative medicine Reproductive cloning Signals Somatic cell Somatic cell nuclear transfer (SCNT) Somatic (adult) stem cell Stem cells Stromal cells Subculturing Surface markers ...

  17. Photovoltaic cell

    Science.gov (United States)

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  18. Fuel cells:

    DEFF Research Database (Denmark)

    Sørensen, Bent

    2013-01-01

    A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil...... and nuclear fuel-based energy technologies....

  19. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  20. Electrochemical Cell

    DEFF Research Database (Denmark)

    1999-01-01

    The invention relates to a rechargeable electrochemical cell comprising a negative electrode, an electrolyte and a positive electrode in which the positive electrode structure comprises a lithium cobalt manganese oxide of the composition Li¿2?Co¿y?Mn¿2-y?O¿4? where 0

  1. Cell Docking, Movement and Cell-Cell Interactions of Heterogeneous Cell Suspensions in a Cell Manipulation Microdevice

    OpenAIRE

    Long-Sun Huang; Yu-Hung Wang; Yu-Wei Chung; Fei-Lung Lai; Shiaw-Min Hwang

    2011-01-01

    This study demonstrates a novel cell manipulation microdevice for cell docking, culturing, cell-cell contact and interaction by microfluidic manipulation of heterogeneous cell suspensions. Heterogeneous cell suspensions include disparate blood cells of natural killer cells and leukemia cancer cells for immune cell transplantation therapy. However, NK cell alloreactivity from different healthy donors present various recovery response levels. Little is still known about the interactions and cyt...

  2. Reprogrammed pluripotent stem cells from somatic cells.

    Science.gov (United States)

    Kim, Jong Soo; Choi, Hyun Woo; Choi, Sol; Do, Jeong Tae

    2011-06-01

    Pluripotent stem cells, such as embryonic stem (ES) cells, can differentiate into all cell types. So, these cells can be a biological resource for regenerative medicine. However, ES cells known as standard pluripotent cells have problem to be used for cell therapy because of ethical issue of the origin and immune response on the graft. Hence, recently reprogrammed pluripotent cells have been suggested as an alternative source for regenerative medicine. Somatic cells can acquire the ES cell-like pluripotency by transferring somatic cell nuclei into oocytes, by cell fusion with pluripotent cells. Retroviral-mediated introduction of four factors, Oct4, Sox2, Klf4 and c-Myc can successfully reprogram somatic cells into ES cell-like pluripotent stem cells, known as induced pluripotent stem (iPS) cells. These cells closely resemble ES cells in gene expression pattern, cell biologic and phenotypic characteristics. However, to reach the eventual goal of clinical application, it is necessary to overcome the major drawbacks such as low reprogramming efficiency and genomic alterations due to viral integration. In this review, we discuss the current reprogramming techniques and mechanisms of nuclear reprogramming induced by transcription factor transduction. PMID:24298328

  3. Ghost cell lesions

    Directory of Open Access Journals (Sweden)

    E Rajesh

    2015-01-01

    Full Text Available Ghost cells have been a controversy for a long time. Ghost cell is a swollen/enlarged epithelial cell with eosnophilic cytoplasm, but without a nucleus. In routine H and E staining these cells give a shadowy appearance. Hence these cells are also called as shadow cells or translucent cells. The appearance of these cells varies from lesion to lesion involving odontogenic and nonodontogenic lesions. This article review about the origin, nature and significance of ghost cells in different neoplasms.

  4. Murine Mueller cells are progenitor cells for neuronal cells and fibrous tissue cells

    International Nuclear Information System (INIS)

    Mammalian Mueller cells have been reported to possess retinal progenitor cell properties and generate new neurons after injury. This study investigates murine Mueller cells under in vitro conditions for their capability of dedifferentiation into retinal progenitor cells. Mueller cells were isolated from mouse retina, and proliferating cells were expanded in serum-containing medium. For dedifferentiation, the cultured cells were transferred to serum-replacement medium (SRM) at different points in time after their isolation. Interestingly, early cell passages produced fibrous tissue in which extracellular matrix proteins and connective tissue markers were differentially expressed. In contrast, aged Mueller cell cultures formed neurospheres in SRM that are characteristic for neuronal progenitor cells. These neurospheres differentiated into neuron-like cells after cultivation on laminin/ornithine cell culture substrate. Here, we report for the first time that murine Mueller cells can be progenitors for both, fibrous tissue cells and neuronal cells, depending on the age of the cell culture

  5. Sickle Cell Information Center

    Science.gov (United States)

    ... Around the Web Google Custom Search – sickle cell Sickle Cell Anemia - In-Depth Report - NY Times Health January 18, 1970 Sickle cell disease (also called sickle cell anemia) is an inherited blood disorder that affects red ...

  6. Electrorefining cell evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Bronson, M.C.; Thomas, R.L. (ed.)

    1989-04-14

    Operational characteristics of the LANL electrorefining cell, a modified LANL electrorefining cell, and an advanced electrorefining cell (known as the CRAC cell) were determined. Average process yields achieved were: 75% for the LANL cell, 82% for the modified LANL cell, and 86% for the CRAC cell. All product metal from the LANL and modified LANL cells was within foundry specifications. Metal from one run in the CRAC cell exceeded foundry specifications for tantalum. The LANL and modified LANL cells were simple in design and operation, but product separation was more labor intensive than with the CRAC cell. The CRAC cell was more complicated in design but remained relatively simple in operation. A decision analysis concluded that the modified LANL cell was the preferred cell. It was recommended that the modified LANL cell be implemented by the Plutonium Recovery Project at Rocky Flats and that development of the CRAC cell continue. 8 refs., 22 figs., 12 tabs.

  7. What are Stem Cells?

    OpenAIRE

    Ahmadshah Farhat; Ashraf Mohammadzadeh; M. Rezaie

    2014-01-01

      Stem cells are undifferentiated self regenerating multi potential cells. There are three types of stem cells categories by the ability to form after cells and correlated with the body’s development process. Totipotent: these stem cells can form an entire organism such as fertilized egg. Ploripotent: ploripotent cells are those that can form any cell in the body but cannot form an entire organism such as developing embryo’s totipotent cells become ploripotent  Multipotent: Multi potent stem ...

  8. Pluripotent stem cell lines

    OpenAIRE

    Yu, Junying; Thomson, James A.

    2008-01-01

    The derivation of human embryonic stem cells 10 years ago ignited an explosion of public interest in stem cells, yet this achievement depended on prior decades of research on mouse embryonic carcinoma cells and embryonic stem cells. In turn, the recent derivation of mouse and human induced pluripotent stem cells depended on the prior studies on mouse and human embryonic stem cells. Both human embryonic stem cells and induced pluripotent stem cells can self-renew indefinitely in vitro while ma...

  9. DNA-cell conjugates

    Energy Technology Data Exchange (ETDEWEB)

    Hsiao, Shih-Chia; Francis, Matthew B.; Bertozzi, Carolyn; Mathies, Richard; Chandra, Ravi; Douglas, Erik; Twite, Amy; Toriello, Nicholas; Onoe, Hiroaki

    2016-05-03

    The present invention provides conjugates of DNA and cells by linking the DNA to a native functional group on the cell surface. The cells can be without cell walls or can have cell walls. The modified cells can be linked to a substrate surface and used in assay or bioreactors.

  10. Molecular Mechanisms of Cell-cell Recognition

    Institute of Scientific and Technical Information of China (English)

    WANG Jia-Huai

    2004-01-01

    Cell-cell recognition is the key for multicellular organisms to survive. This recognition critically depends on protein-protein interactions from opposing cell surfaces. Recent structural investigations reveal unique features of these cell surface receptors and how they interact. These interactions are specific, but usually relatively weak, with more hydrophilic forces involved in binding. The receptors appear to have specialized ways to present their key interacting elements for ligand-binding from the cell surface. Cell-cell contacts are multivalent. A large group of cell surface molecules are engaged in interactions. Characteristic weak interactions make possible for each individual molecule pair within the group to constantly associate-dissociate-reassociate, such that the cell-cell recognition becomes a dynamic process. The immunological synapse is a good example for immune receptors to be orchestrated in performing immunological function in a collective fashion.

  11. nduced pluripotent stem cells and cell therapy

    Directory of Open Access Journals (Sweden)

    Banu İskender

    2013-12-01

    Full Text Available Human embryonic stem cells are derived from the inner cell mass of a blastocyst-stage embryo. They hold a huge promise for cell therapy with their self-renewing ability and pluripotency, which is known as the potential to differentiate into all cell types originating from three embryonic germ layers. However, their unique pluripotent feature could not be utilised for therapeutic purposes due to the ethical and legal problems during derivation. Recently, it was shown that the cells from adult tissues could be reverted into embryonic state, thereby restoring their pluripotent feature. This has strenghtened the possiblity of directed differentition of the reprogrammed somatic cells into the desired cell types in vitro and their use in regenerative medicine. Although these cells were termed as induced pluripotent cells, the mechanism of pluripotency has yet to be understood. Still, induced pluripotent stem cell technology is considered to be significant by proposing novel approaches in disease modelling, drug screening and cell therapy. Besides their self-renewing ability and their potential to differentiate into all cell types in a human body, they arouse a great interest in scientific world by being far from the ethical concerns regarding their embryonic counterparts and their unique feature of being patient-specific in prospective cell therapies. In this review, induced pluripotent stem cell technology and its role in cell-based therapies from past to present will be discussed. J Clin Exp Invest 2013; 4 (4: 550-561

  12. Modeling cell-in-cell structure into its biological significance

    OpenAIRE

    He, M-f; S. Wang; Wang, Y.; Wang, X-N.

    2013-01-01

    Although cell-in-cell structure was noted 100 years ago, the molecular mechanisms of ‘entering' and the destination of cell-in-cell remain largely unclear. It takes place among the same type of cells (homotypic cell-in-cell) or different types of cells (heterotypic cell-in-cell). Cell-in-cell formation affects both effector cells and their host cells in multiple aspects, while cell-in-cell death is under more intensive investigation. Given that cell-in-cell has an important role in maintainin...

  13. Monitoring cell growth.

    Science.gov (United States)

    Strober, W

    2001-05-01

    This appendix provides two protocols for monitoring cell growth. Counting cells using a hemacytometer is tedious but it allows one to effectively distinguish live cells from dead cells (using Trypan Blue exclusion). In addition, this procedure is less subject to errors due to cell clumping or heterogeneity of cell size. The use of an electronic cell counter is quicker and easier than counting cells using a hemacytometer. However, an electronic cell counter as currently constructed does not distinguish live from dead cells in a reliable fashion and is subject to error due to the presence of cell clumps. Overall, the electronic cell counter is best reserved for repetitive and rapid counting of fresh peripheral blood cells and should be used with caution when counting cell populations derived from tissues. PMID:18432653

  14. Automated Cell-Cutting for Cell Cloning

    Science.gov (United States)

    Ichikawa, Akihiko; Tanikawa, Tamio; Matsukawa, Kazutsugu; Takahashi, Seiya; Ohba, Kohtaro

    We develop an automated cell-cutting technique for cell cloning. Animal cells softened by the cytochalasin treatment are injected into a microfluidic chip. The microfluidic chip contains two orthogonal channels: one microchannel is wide, used to transport cells, and generates the cutting flow; the other is thin and used for aspiration, fixing, and stretching of the cell. The injected cell is aspirated and stretched in the thin microchannel. Simultaneously, the volumes of the cell before and after aspiration are calculated; the volumes are used to calculate the fluid flow required to aspirate half the volume of the cell into the thin microchannel. Finally, we apply a high-speed flow in the orthogonal microchannel to bisect the cell. This paper reports the cutting process, the cutting system, and the results of the experiment.

  15. Proceedings of the Joint Meeting of The Fuel Society of Japan (1991). 28th Coal Science Conference/91st Coke Meeting; (Sha) nenryo kyokai godo taikai happyo ronbunshu (1991). Dai 28 kai sekitan kagaku kaigi dai 91 kai cokes tokubetsukai

    Energy Technology Data Exchange (ETDEWEB)

    1991-11-07

    Relating to coke, studies are made on the rapid coke production method, oven investigation during carbonization, and operational management/control. As to coal science, studies are mainly on the brown coal two-stage liquefaction (BCL) method, and data on the pilot plant and PSU are reported. Concerning bituminous coal liquefaction, PSU data mostly including the NEDOL process, and characteristics of liquefaction residue and its effective utilization by thermal decomposition are reported. Regarding the liquefaction mechanism, an experimentally extensive study on catalyst, solvent and reaction conditions is made using model materials and coal itself on the bench scale and also in the pilot plant. Engineering subjects on residue, solvent deashing, scale attachment and coprocessing are also reported. Relations of decomposition process to coal chemical structure changes and reaction conditions are investigated. As to coal gasification, studies, which are not many, are conducted on material balance, heat balance, and image characteristics of char for gasification and factors controlling reactivity.

  16. Attempt of lean burn of a 4 cycle gasoline engine by the aid of low pressure air assisted in-cylinder injection; Tonai kuki nenryo funsha ni yoru lean burn no kokoromi

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, S.; Kondo, M.; Sekiya, Y.; Murayama, T. [Hokkaido Automotive Engineering College, Hokkaido (Japan)

    1997-10-01

    Comparable performance and exhaust emission with conventional carburetor was obtained by a low Pressure air assisted in-cylinder injection system. And lean burn of idling and light load operation till A/F=70 was realized by installing a spark Plug and a reed type injection nozzle in a divided combustion chambaer of a 4 cycle gasoline engine. 2 refs., 10 figs.

  17. Injection and spray characteristics of a variable orifice nozzle applied the jerk type fuel injection pump for DI diesel engine; Jerk shiki nenryo funsha pump wo mochiita kahen funko nozzle no funsha funmu tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, T.; Matsui, K.; Iwasaki, T.; Kobayashi, T. [Zexel Corp., Tokyo (Japan); Matsumoto, Y. [The University of Tokyo, Tokyo (Japan)

    1997-10-01

    A Variable Orifice Nozzle (VON) by changing a cross-sectional area of the nozzle injection hole, for improving a rate of injection and injection duration, has been developed to study its injection and spray characteristics. The nozzle geometry was optimized to analyze a nozzle internal flow by computational method. Results show that, injection and spray pattern responded to the nozzle orifice cross-sectional area which is changing larger to smaller in the part load range. This results suggest to contribute a combustion improvement which decreasing NOx and soot. 14 refs., 10 figs.

  18. Study of a fuel injection quantity sensor in diesel engine. Part 3. Experimental evaluation of the improved type micro turbine sensor; Diesel kikan ni okeru nenryo funsharyo sensor no kenkyu. 3. Funsharyo keisoku no seido kojo ni kansuru jikken hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Maehara, H.; Iwasaki, T.; Kobayashi, T. [Zexel Corp., Tokyo (Japan)

    1997-10-01

    A Micro Turbine Sensor has been developed to measure fuel injection quantity and injection rate. Previous reports described results of experiments on the MTS which were carried out under steady and unsteady flow conditions. The MTS has been improved in shape of a holder tip and a detecting procedure for rotating speed of a turbine. As a result revolution speed of the turbine increased 18% over the conventional type holder under steady flow condition. Furthermore the measurement resolution of the MTS came up to about 2(mm{sup 3}/pulse) at 20(mm{sup 3}/stroke) under intermittent spray conditions using fuel injection pump. 11 refs., 11 figs., 1 tab.

  19. Spray characteristics of dimethyl ether (D.M.E.) as on alternative fuel for diesel engine; Daitai diesel nenryo to shite no dimethyl ether (D.M.E.) no funmu tokusei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Wakai, K.; Nishida, K.; Yoshizaki, T.; Hiroyasu, H. [Hiroshima University, Hiroshima (Japan)

    1997-10-01

    D.M.E. which was paid attention to as on alternative fuel for a diesel engine, was injected by using Bosch type injection pump and a hole nozzle into a high pressure and high temperature vessel. The spray was observed by using schlieren photography. Spray characteristics, such as, the tip penetration, the cone angle and the volume of the spray were and were compared with a diesel fuel spray. The following thing, and so on were found out as a results. The spray angle of the DME spray of atmosphere pressure Pa=0.1Mpa spreads out large in comparison with the diesel fuel spray, and the way of the change by the pressure is contrary to the case of the diesel fuel spray. 3 refs., 6 figs., 1 tab.

  20. Three-dimensional analysis of internal flow characteristics in the injection nozzle tip of direct-injection diesel engines; Sanjigen suchi kaiseki ni yoru DI diesel kikan no nenryo funsha nozzle nai ryudo tokusei no kaimei

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, H.; Matsui, Y.; Kimura, S. [Nissan Motor Co. Ltd. Tokyo (Japan)

    1997-10-01

    To reduce the exhaust emissions and fuel consumption of direct-injection diesel engines, it is essential to optimize the fuel injection equipment closely related to combustion and emission characteristics. In this study, three-dimensional computation has been applied to investigate the effects of the injection nozzle specifications (e.g., sac volume, round shape at the inlet of the nozzle hole) and needle tip deviation on internal flow characteristics. The computational results revealed that the effects of the nozzle specifications and needle tip deviation with a smaller needle lift on internal flow characteristics and a general approach to optimize the injection nozzle specifications were obtained. 3 refs., 10 figs., 1 tab.

  1. World scenario for energy industries (Problems and responses). ; Creating new values in fuels and restructuring the energy industries. Energy sangyo no sekai shinario (kadai to taio). ; Nenryo no shinkachi no sozo to energy sangyo no saikochiku

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-05

    This paper describes the following matters on the future images of the energy industries: The following two scenarios may be drawn on the future world order from the changing signs seen in three regions of the geopolitical factors, international economies, and environmental problems : One is the world of mercantilism where several blocks are formed, with the economic power of each block regarded as the ultimate purpose. Trades within a block are executed according to the market principles, while trades between the blocks are operated politically. The energy industries in this case should face incessantly new rules and market restructuring. Another scenario is a coordination maintaining world where international cooperations are preferred to the common benefits. Affluent nations determine the necessity of global systems for trade and environmental problems, while less affluent nations are forced to coordinate with these determinations. In this case, the energy industries will face directly a cost rise associated with conversions to cleaner fuels and industrial restructuring. 8 figs.

  2. Research on the general analytical method of fossil fuel cycle from a viewpoint of the global environment. 3; Chikyu kankyo kara mita sogoteki kaseki nenryo cycle bunseki hyoka shuho no chosa. 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The general analysis/assessment method of a fossil fuel cycle was studied. Seven kinds of power generation plants such as LNG cycle and coal cycle ones, and four kinds of transport and treatment systems of recovered CO2 such as ocean and underground systems were studied as case studies on life cycle analysis. As data necessary for life cycle analysis, the database was constructed which stores the facilities and operational energy required for a total energy system from mining of fossil fuel to treatment of recovered CO2, and the quantity of environmental waste such as CO2 emission. As a result, the decrease rate of energy balance defined as ratio of input energy to power plant output was estimated to be 14-43% and 20-60% in LNG cycle and coal cycle, respectively. Even if the recovery rate of CO2 in power plants reached 80-90%, reduction of total CO2 emission was limited to only 20-40% because of CO2 emission during mining, liquefaction and transport of fuel. 168 refs., 48 figs., 102 tabs.

  3. Research report for fiscal 1998. Research concerning studies for development of thermochemical solar hybrid fuel production system; 1998 nendo chosa hokokusho. Netsukagakuteki solar hybrid nenryo seisan system no kaihatsu kenkyu ni kakawaru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A solar heat-aided system is investigated, in which CO2 is recycled, with methanol, dimethyl ether, etc., serving as carriers of the solar heat energy. In the evaluation of validity of the system as a whole, the system scale and economy and technologies necessary for the system were studied, which was to find out whether solar methanol production was commercially feasible in the sun belt. It was concluded that solar methanol was capable of competing against LNG (liquefied natural gas) in cost, that Japan was able to establish its own technologies for developing coal gasification solar reactors using overseas technologies for information, and that therefore such a system was technologically and economically valid. In the study of related technologies as is, surveys were conducted on coal gasification, natural gas reforming furnaces, methanol synthesis, dimethyl ether synthesis, light condensing technology, current state and cost of solar reactors, etc. Also investigated were the marketability of solar hybrid fuel, CO2 reduction efficiency, and the construction cost at the assumed site of construction (Australia). (NEDO)

  4. Sickle Cell Anemia

    Science.gov (United States)

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells are shaped like a crescent or sickle. They ... last as long as normal, round red blood cells. This leads to anemia. The sickle cells also ...

  5. CELL RESEARCH

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    REVIEWSInducible resistance to Fas-mediated apoptosis in B cells…………………………………ROTHSTEIN Thomas L (245)Executionary pathway for apoptosis: lessons from mutant mice………………………………………WOO Minna, Razqallah Hakem, Tak W Mak (267)The SHP-2 tyrosine phosphatase: Signaling mechanisms and biological functions…………………………………QU Cheng Kui (279)REGULAR ARTICLESTemperature dependent expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis…………………………KONG Wei Hua, Zheng GU, Jining LU, Jiake TSO (289)Transgenic mice overexpressing γ-aminobutyric acid transporter subtype I develop obesity…………………………………MA Ying Hua, Jia Hua HU, Xiao Gang ZHOU, Ruo Wang ZENG, Zhen Tong MEI, Jian FEI, Li He GUO (303)Genetic aberration in primary hepatocellular carcinoma: correlation between p53 gene mutation and loss-of-heterozygosity on chromosome 16q21-q23 and 9p21-p23………………………………………WANG Gang, Chang Hui HUANG, Yan ZHAO, Ling CAI, Ying WANG, Shi Jin XIU, Zheng Wen JIANG, Shuang YANG, Xin Tai ZHAO, Wei HUANG, Jian Ren GU (311)Identification and genetic mapping of four novel genes that regulate leaf deve- lopment in Arabidopsis………………………………………………SUN Yue, Wei ZHANG, Feng Ling LI, Ying Li GUO, Tian Lei LIU, Hai HUANG (325)NOTICE FOR CONTRIBUTORS…………………………………(337)CONTENTS of Vol. 10, 2000…………………………………………………(338)

  6. Cell Membrane Softening in Cancer Cells

    Science.gov (United States)

    Schmidt, Sebastian; Händel, Chris; Käs, Josef

    Biomechanical properties are useful characteristics and regulators of the cell's state. Current research connects mechanical properties of the cytoskeleton to many cellular processes but does not investigate the biomechanics of the plasma membrane. We evaluated thermal fluctuations of giant plasma membrane vesicles, directly derived from the plasma membranes of primary breast and cervical cells and observed a lowered rigidity in the plasma membrane of malignant cells compared to non-malignant cells. To investigate the specific role of membrane rigidity changes, we treated two cell lines with the Acetyl-CoA carboxylase inhibitor Soraphen A. It changed the lipidome of cells and drastically increased membrane stiffness by up regulating short chained membrane lipids. These altered cells had a decreased motility in Boyden chamber assays. Our results indicate that the thermal fluctuations of the membrane, which are much smaller than the fluctuations driven by the cytoskeleton, can be modulated by the cell and have an impact on adhesion and motility.

  7. Sickle cell anemia - resources

    Science.gov (United States)

    Resources - sickle cell anemia ... The following organizations are good resources for information on sickle cell anemia : American Sickle Cell Anemia Association -- www.ascaa.org National Heart, Blood, and Lung Institute -- www. ...

  8. Sickle Cell Disease

    Science.gov (United States)

    ... in Sickle Cell Disease New supplement from the American Journal of Preventive Medicine describes the state of sickle cell disease related care in the United States. Read Supplement » ... are affected by sickle cell disease. More WEBINAR ...

  9. Sickle Cell Disease

    Science.gov (United States)

    ... from the NHLBI on Twitter. What Is Sickle Cell Disease? Español The term sickle cell disease (SCD) ... common forms of SCD. Some Forms of Sickle Cell Disease Hemoglobin SS Hemoglobin SC Hemoglobin Sβ 0 thalassemia ...

  10. Squamous cell skin cancer

    Science.gov (United States)

    ... earliest form of squamous cell cancer is called Bowen disease (or squamous cell carcinoma in situ). This type ... cancer; Squamous cell carcinoma of the skin Images Bowen's disease on the hand Keratoacanthoma Keratoacanthoma Skin cancer, squamous ...

  11. Lung cancer - small cell

    Science.gov (United States)

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC ...

  12. GSPEL - Fuel Cell Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Fuel Cell Lab (FCL) Provides testing for technology readiness of fuel cell systems The FCL investigates, tests and verifies the performance of fuel-cell systems...

  13. Lung cancer - small cell

    Science.gov (United States)

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  14. Basal Cell Carcinoma (BCC)

    Science.gov (United States)

    ... epithelioma, is the most common form of skin cancer. Basal cell carcinoma usually occurs on sun-damaged skin, especially ... other health issues. Infiltrating or morpheaform basal cell carcinomas: Infiltrating basal cell carcinomas can be more aggressive and locally destructive ...

  15. Immobilization of cells via activated cell walls

    Energy Technology Data Exchange (ETDEWEB)

    Markt, M.; Kas, J.; Valentova, O.; Demnerova, K.; Vodrazka, Z.

    1986-10-01

    Cell walls of Saccharomyces cerevisiae and S. uvarum were activated by periodate oxidation of vicinal diol groups in cell wall polysaccharides. The aldehyde groups thus generated allow the yeast cells to be covalently bound to modified bead cellulose or macroporous glycidyl methacrylate supports, or to enzymes such as glucose oxidase and catalase. 6 references.

  16. Snail modulates cell metabolism in MDCK cells

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Misako, E-mail: haraguci@m3.kufm.kagoshima-u.ac.jp [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Indo, Hiroko P. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Iwasaki, Yasumasa [Health Care Center, Kochi University, Kochi 780-8520 (Japan); Iwashita, Yoichiro [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Fukushige, Tomoko [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Majima, Hideyuki J. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Izumo, Kimiko; Horiuchi, Masahisa [Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Kanekura, Takuro [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Furukawa, Tatsuhiko [Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Ozawa, Masayuki [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan)

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  17. Cell aggregation and sedimentation.

    Science.gov (United States)

    Davis, R H

    1995-01-01

    The aggregation of cells into clumps or flocs has been exploited for decades in such applications as biological wastewater treatment, beer brewing, antibiotic fermentation, and enhanced sedimentation to aid in cell recovery or retention. More recent research has included the use of cell aggregation and sedimentation to selectively separate subpopulations of cells. Potential biotechnological applications include overcoming contamination, maintaining plasmid-bearing cells in continuous fermentors, and selectively removing nonviable hybridoma cells from perfusion cultures.

  18. Artificial Stem Cell Niches

    OpenAIRE

    Lutolf, Matthias P.; Blau, Helen M.

    2009-01-01

    Stem cells are characterized by their dual ability to reproduce themselves (self-renew) and specialize (differentiate), yielding a plethora of daughter cells that maintain and regenerate tissues. In contrast to their embryonic counterparts, adult stem cells retain their unique functions only if they are in intimate contact with an instructive microenvironment, termed stem cell niche. In these niches, stem cells integrate a complex array of molecular signals that, in concert with induced cell-...

  19. Fish Stem Cell Cultures

    OpenAIRE

    Ni Hong, Zhendong Li, Yunhan Hong

    2011-01-01

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is th...

  20. Stem Cell Separation Technologies

    OpenAIRE

    Zhu, Beili; Murthy, Shashi K

    2013-01-01

    Stem cell therapy and translational stem cell research require large-scale supply of stem cells at high purity and viability, thus leading to the development of stem cell separation technologies. This review covers key technologies being applied to stem cell separation, and also highlights exciting new approaches in this field. First, we will cover conventional separation methods that are commercially available and have been widely adapted. These methods include Fluorescence-activated cell so...

  1. Cell control report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This extensive report provides an essential overview of cells and their use as factory automation building blocks. The following issues are discussed in depth: Cell integration Cell software and standards Future technologies applied to cells Plus Cell control applications including: - rotary parts manufacturing - diesel engine component development - general cell control development at the General Electric Corporation - a vendor list.

  2. Fusion with stem cell makes the hepatocellular carcinoma cells similar to liver tumor-initiating cells

    OpenAIRE

    Wang, Ran; Chen, Shuxun; Li, Changxian; Ng, Kevin Tak Pan; Kong, Chi-Wing; Cheng, Jinping; Cheng, Shuk Han; Li, Ronald A.; Lo, Chung Mau; Man, Kwan; Sun, Dong

    2016-01-01

    Background Cell fusion is a fast and highly efficient technique for cells to acquire new properties. The fusion of somatic cells with stem cells can reprogram somatic cells to a pluripotent state. Our research on the fusion of stem cells and cancer cells demonstrates that the fused cells can exhibit stemness and cancer cell-like characteristics. Thus, tumor-initiating cell-like cells are generated. Methods We employed laser-induced single-cell fusion technique to fuse the hepatocellular carci...

  3. Cancer stem cell-like cells from a single cell of oral squamous carcinoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Felthaus, O. [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany); Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Ettl, T.; Gosau, M.; Driemel, O. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Brockhoff, G. [Department of Gynecology and Obstetrics, University of Regensburg (Germany); Reck, A. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Zeitler, K. [Institute of Pathology, University of Regensburg (Germany); Hautmann, M. [Department of Radiotherapy, University of Regensburg (Germany); Reichert, T.E. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Schmalz, G. [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany); Morsczeck, C., E-mail: christian.morsczeck@klinik.uni-regensburg.de [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany)

    2011-04-01

    Research highlights: {yields} Four oral squamous cancer cell lines (OSCCL) were analyzed for cancer stem cells (CSCs). {yields} Single cell derived colonies of OSCCL express CSC-marker CD133 differentially. {yields} Monoclonal cell lines showed reduced sensitivity for Paclitaxel. {yields} In situ CD133{sup +} cells are slow cycling (Ki67-) indicating a reduced drug sensitivity. {yields} CD133{sup +} and CSC-like cells can be obtained from single colony forming cells of OSCCL. -- Abstract: Resistance of oral squamous cell carcinomas (OSCC) to conventional chemotherapy or radiation therapy might be due to cancer stem cells (CSCs). The development of novel anticancer drugs requires a simple method for the enrichment of CSCs. CSCs can be enriched from OSCC cell lines, for example, after cultivation in serum-free cell culture medium (SFM). In our study, we analyzed four OSCC cell lines for the presence of CSCs. CSC-like cells could not be enriched with SFM. However, cell lines obtained from holoclone colonies showed CSC-like properties such as a reduced rate of cell proliferation and a reduced sensitivity to Paclitaxel in comparison to cells from the parental lineage. Moreover, these cell lines differentially expressed the CSC-marker CD133, which is also upregulated in OSCC tissues. Interestingly, CD133{sup +} cells in OSCC tissues expressed little to no Ki67, the cell proliferation marker that also indicates reduced drug sensitivity. Our study shows a method for the isolation of CSC-like cell lines from OSCC cell lines. These CSC-like cell lines could be new targets for the development of anticancer drugs under in vitro conditions.

  4. Cancer stem cell-like cells from a single cell of oral squamous carcinoma cell lines

    International Nuclear Information System (INIS)

    Research highlights: → Four oral squamous cancer cell lines (OSCCL) were analyzed for cancer stem cells (CSCs). → Single cell derived colonies of OSCCL express CSC-marker CD133 differentially. → Monoclonal cell lines showed reduced sensitivity for Paclitaxel. → In situ CD133+ cells are slow cycling (Ki67-) indicating a reduced drug sensitivity. → CD133+ and CSC-like cells can be obtained from single colony forming cells of OSCCL. -- Abstract: Resistance of oral squamous cell carcinomas (OSCC) to conventional chemotherapy or radiation therapy might be due to cancer stem cells (CSCs). The development of novel anticancer drugs requires a simple method for the enrichment of CSCs. CSCs can be enriched from OSCC cell lines, for example, after cultivation in serum-free cell culture medium (SFM). In our study, we analyzed four OSCC cell lines for the presence of CSCs. CSC-like cells could not be enriched with SFM. However, cell lines obtained from holoclone colonies showed CSC-like properties such as a reduced rate of cell proliferation and a reduced sensitivity to Paclitaxel in comparison to cells from the parental lineage. Moreover, these cell lines differentially expressed the CSC-marker CD133, which is also upregulated in OSCC tissues. Interestingly, CD133+ cells in OSCC tissues expressed little to no Ki67, the cell proliferation marker that also indicates reduced drug sensitivity. Our study shows a method for the isolation of CSC-like cell lines from OSCC cell lines. These CSC-like cell lines could be new targets for the development of anticancer drugs under in vitro conditions.

  5. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  6. SMOOTH MUSCLE STEM CELLS

    Science.gov (United States)

    Vascular smooth muscle cells (SMCs) originate from multiple types of progenitor cells. In the embryo, the most well-studied SMC progenitor is the cardiac neural crest stem cell. Smooth muscle differentiation in the neural crest lineage is controlled by a combination of cell intrinsic factors, includ...

  7. Sickle Cell Disease

    Science.gov (United States)

    ... sickle cell disease? Sickle cell disease, also called sickle cell anemia, is a hereditary condition (which means it runs ... or blocks blood and oxygen reaching nearby tissues. Sickle cell disease ... the whites of the eyes) Anemia (the decreased ability of the blood to carry ...

  8. When Blood Cells Bend: Understanding Sickle Cell Disease

    Science.gov (United States)

    ... please review our exit disclaimer . Subscribe When Blood Cells Bend Understanding Sickle Cell Disease For people who don’t suspect they ... Cells Bend Wise Choices Links Living with Sickle Cell Disease See a sickle cell disease expert regularly. ...

  9. FY1995 study on property-gradient polymer electrolyte for rechargeable lithium batteries; 1995 nendo lithium niji denchi no tame no keisha tokusei kobunshi denkaishitsu no sosei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Polymer electrolytes are essential materials to develop safe and reliable rechargeable lithium batteries. Nobel 'property-gradient' polymer electrolytes in which ionic conductivity distributes along with their thickness were synthesized by employing plasma polymerization technology. Vinyl monomers bound with oligo-ether side chains via siloxane bond were served as starting monomers for plasma polymerization. Ionic conductivity of formed polymers changed along with their thickness. Monomer solutions containing lithium salt which were impregnated into porous matrix were polymerized by exposing RF plasma and directly gave polymer electrolytes. The polymer electrolytes showed distributing ionic conductivity through its direction of thickness; 'property-gradient' polymer electrolyte were prepared. Metallic lithium surface were covered with thin plasma polymer layer containing fluorine to suppress dendritic lithium deposition during charging. The layer reacted so fast that suppression of the dendritic deposition was not satisfactory. (NEDO)

  10. Valuation of the quantity of electric output from photovoltaic generation system in case of PV module applied to installing to vertical direction; Taiyo denchi wo suichoku ni haichishita baai no hatsudenryo hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Miyajima, K. [Kansai Electric Power Co. Inc., Osaka (Japan)

    1996-10-27

    In general, it is most efficient and economical to install photovoltaic (PV) modules with proper slope. There are room spaces on the wall except ground or roof. The PV modules were installed on the vertical wall, to consider the compensative method for this weak point. When modules were installed vertically, there is an advantage that reflecting solar light as well as incident solar light can be utilized compared with the installation with slope. The PV modules were installed on the roof of building with inclination of 90{degree} facing to south using the roof material as a reflecting material (S90), and with inclination of 15{degree} facing to south (S15), to compare their output. The output ratio, S90/S15 was 0.42. When it was very fine, this value increased to 0.60. When using plated steel plate as the reflecting material, this value increased to 0.74, which provided 10 to 30% larger output than the roof material. From these results, about 50% of module output of S15 can be expected for S90. If receiving larger reflection, there would only a slight difference in the module output between S15 and S90. 3 figs., 1 tab.

  11. Ganglion cell like cells, diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Anand Shankar Ammanagi

    2013-01-01

    Full Text Available We report a case of cutaneous swelling found on the left anterior axillary fold of a 41-year-old man. Gross examination of specimen excised from the dermis showed a well-circumscribed nodule histologically composed of spindle cells with interspersed ganglion cell like cells. On hematoxylin and eosine (H and E staining it was diagnosed as ganglioneuroma. Ganglioneuromas are rare, benign, fully differentiated tumors that contain mature schwann cells, ganglion cells, fibrous tissue, and nerve fibers. They are commonly found along the paravertebral sympathetic ganglia and sometimes in the adrenal medulla. However primary cutaneous ganglioneuroma is an extremely rare tumor. Immunohistochemical workup revealed a fibroblastic origin and hence the case was diagnosed as fibromatosis with ganglion cell like fibroblasts. This case report suggests that the features considered diagnostic of ganglioneuromas can occur in other cutaneous lesions and, therefore, this diagnosis cannot be offered only on the basis of H and E.

  12. Cell fusion of bone marrow cells and somatic cell reprogramming by embryonic stem cells

    OpenAIRE

    Bonde, Sabrina; Pedram, Mehrdad; Stultz, Ryan; Zavazava, Nicholas

    2010-01-01

    Bone marrow transplantation is a curative treatment for many diseases, including leukemia, autoimmune diseases, and a number of immunodeficiencies. Recently, it was claimed that bone marrow cells transdifferentiate, a much desired property as bone marrow cells are abundant and therefore could be used in regenerative medicine to treat incurable chronic diseases. Using a Cre/loxP system, we studied cell fusion after bone marrow transplantation. Fused cells were chiefly Gr-1+, a myeloid cell mar...

  13. Hepatic stem cell niches

    OpenAIRE

    Kordes, Claus; Häussinger, Dieter

    2013-01-01

    Stem cell niches are special microenvironments that maintain stem cells and control their behavior to ensure tissue homeostasis and regeneration throughout life. The liver has a high regenerative capacity that involves stem/progenitor cells when the proliferation of hepatocytes is impaired. In recent years progress has been made in the identification of potential hepatic stem cell niches. There is evidence that hepatic progenitor cells can originate from niches in the canals...

  14. Stem Cell Networks

    OpenAIRE

    Werner, Eric

    2016-01-01

    We present a general computational theory of stem cell networks and their developmental dynamics. Stem cell networks are special cases of developmental control networks. Our theory generates a natural classification of all possible stem cell networks based on their network architecture. Each stem cell network has a unique topology and semantics and developmental dynamics that result in distinct phenotypes. We show that the ideal growth dynamics of multicellular systems generated by stem cell ...

  15. Stem cell mechanobiology

    OpenAIRE

    David A. Lee; Knight, Martin M.; Jonathan J Campbell; Bader, Dan L.

    2010-01-01

    Stem cells are undifferentiated cells that are capable of proliferation, self-maintenance and differentiation towards specific cell phenotypes. These processes are controlled by a variety of cues including physicochemical factors associated with the specific mechanical environment in which the cells reside. The control of stem cell biology through mechanical factors remains poorly understood and is the focus of the developing field of mechanobiology. This review provides an insight into the c...

  16. Embryonic Stem Cell Markers

    OpenAIRE

    Lan Ma; Liang Li; Wenxiu Zhao; Xiang Ji; Fangfang Zhang

    2012-01-01

    Embryonic stem cell (ESC) markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES cells. Unfortunately, different cell types can share single or sometimes multiple markers; thus the main obstacle in the clinical application of ESC is to purify ES cells from other type...

  17. Limbal stem cell transplantation

    OpenAIRE

    Fernandes Merle; Sangwan Virender; Rao Srinivas; Basti Surendra; Sridhar Mittanamalli; Bansal Aashish; Dua Harminder

    2004-01-01

    The past two decades have witnessed remarkable progress in limbal stem cell transplantation. In addition to harvesting stem cells from a cadaver or a live related donor, it is now possible to cultivate limbal stem cells in vitro and then transplant them onto the recipient bed. A clear understanding of the basic disease pathology and a correct assessment of the extent of stem cell deficiency are essential. A holistic approach towards management of limbal stem cell deficiency is needed. This ...

  18. Intraoperative Stem Cell Therapy

    OpenAIRE

    Coelho, Mónica Beato; Cabral, Joaquim M. S.; Karp, Jeffrey M.

    2012-01-01

    Stem cells hold significant promise for regeneration of tissue defects and disease-modifying therapies. Although numerous promising stem cell approaches are advancing in clinical trials, intraoperative stem cell therapies offer more immediate hope by integrating an autologous cell source with a well-established surgical intervention in a single procedure. Herein, the major developments in intraoperative stem cell approaches, from in vivo models to clinical studies, are reviewed, and the poten...

  19. The leukemic stem cell

    OpenAIRE

    Jordan, Craig T.

    2007-01-01

    Malignant stem cells have recently been described as the source of several types of human cancer. These unique cell types are typically rare and possess properties that are distinct from most other tumor cells. The properties of leukemic stem cells indicate that current chemotherapy drugs will not be effective. The use of current cytotoxic agents is not effective in leukemia because the agents target both the leukemic and normal stem cell populations. Consequently, new strategies are required...

  20. Cancer Stem Cells

    OpenAIRE

    Katarzyna Wieczorek; Jolanta Niewiarowska

    2008-01-01

    Cancer stem cell theory gains increasingly greater significance in the world of medicine. Numerous findings of scientific research in vivo and in vitro indicate that it is the population of undifferentiated, self-renewing cells which is responsible for recurrence of cancer and metastasis. Similarly to normal stem cells, cancer stem cells (CSC) function in the environment of the other cells of the organism, called the niche, where they receive signals for differentiation and proliferation proc...

  1. The cell cycle as a brake for β-cell regeneration from embryonic stem cells

    OpenAIRE

    El-Badawy, Ahmed; El-Badri, Nagwa

    2016-01-01

    The generation of insulin-producing β cells from stem cells in vitro provides a promising source of cells for cell transplantation therapy in diabetes. However, insulin-producing cells generated from human stem cells show deficiency in many functional characteristics compared with pancreatic β cells. Recent reports have shown molecular ties between the cell cycle and the differentiation mechanism of embryonic stem (ES) cells, assuming that cell fate decisions are controlled by the cell cycle ...

  2. Mechanically facilitated cell-cell electrofusion.

    OpenAIRE

    Jaroszeski, M. J.; Gilbert, R.; Fallon, P.G.; Heller, R

    1994-01-01

    Apparatus and methods were developed to enable mechanically facilitated cell-cell electrofusion to be performed. The apparatus and methods mechanically place cells in contact before fusion. The key component of this fusion system was a newly developed fusion chamber. The chamber was composed of two functionally identical electrodes that were housed in a multi-layer structure. The layers functioned as support for the electrodes. They also allowed adjustment of the distance between opposing ele...

  3. Optimizing stem cell culture.

    Science.gov (United States)

    van der Sanden, Boudewijn; Dhobb, Mehdi; Berger, François; Wion, Didier

    2010-11-01

    Stem cells always balance between self-renewal and differentiation. Hence, stem cell culture parameters are critical and need to be continuously refined according to progress in our stem cell biology understanding and the latest technological developments. In the past few years, major efforts have been made to define more precisely the medium composition in which stem cells grow or differentiate. This led to the progressive replacement of ill-defined additives such as serum or feeder cell layers by recombinant cytokines or growth factors. Another example is the control of the oxygen pressure. For many years cell cultures have been done under atmospheric oxygen pressure which is much higher than the one experienced by stem cells in vivo. A consequence of cell metabolism is that cell culture conditions are constantly changing. Therefore, the development of high sensitive monitoring processes and control algorithms is required for ensuring cell culture medium homeostasis. Stem cells also sense the physical constraints of their microenvironment. Rigidity, stiffness, and geometry of the culture substrate influence stem cell fate. Hence, nanotopography is probably as important as medium formulation in the optimization of stem cell culture conditions. Recent advances include the development of synthetic bioinformative substrates designed at the micro- and nanoscale level. On going research in many different fields including stem cell biology, nanotechnology, and bioengineering suggest that our current way to culture cells in Petri dish or flasks will soon be outdated as flying across the Atlantic Ocean in the Lindbergh's plane. PMID:20803548

  4. Living with Sickle Cell Disease

    Science.gov (United States)

    ... sickle cell disease, go to the Health Topics Sickle Cell Anemia article. Living With and Managing Sickle Cell Disease ( ... the most severe form of sickle cell disease, sickle cell anemia, Tiffany has lived with the symptoms and complications ...

  5. What Causes Sickle Cell Disease?

    Science.gov (United States)

    ... sickle cell disease, go to the Health Topics Sickle Cell Anemia article. Living With and Managing Sickle Cell Disease ( ... the most severe form of sickle cell disease, sickle cell anemia, Tiffany has lived with the symptoms and complications ...

  6. Plant stem cell niches.

    Science.gov (United States)

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

  7. What are Stem Cells?

    Directory of Open Access Journals (Sweden)

    Ahmadshah Farhat

    2014-05-01

    Full Text Available   Stem cells are undifferentiated self regenerating multi potential cells. There are three types of stem cells categories by the ability to form after cells and correlated with the body’s development process. Totipotent: these stem cells can form an entire organism such as fertilized egg. Ploripotent: ploripotent cells are those that can form any cell in the body but cannot form an entire organism such as developing embryo’s totipotent cells become ploripotent  Multipotent: Multi potent stem cells are those that can only form specific cells in the body such as blood cells based. Based on the sources of stem cells we have three types of these cells: Autologous: Sources of the patient own cells are (Autologous either the cells from patient own body or his or her cord blood. For this type of transplant the physician now usually collects the periphery rather than morrow because the procedure is easier on like a bane morrow harvest it take place outside of an operating room, and the patient does not to be under general unsetting . Allogenic: Sources of stem cells from another donore are primarily relatives (familial allogenic or completely unrelated donors. Xenogenic: In these stem cells from different species are transplanted e .g striatal porcine fetal mesan cephalic (FVM xenotransplants for Parkinson’s disease. On sites of isolation such as embryo, umbilical cord and other body tissues stem cells are named embnyonic, cord blood, and adult stem cells. The scope of results and clinical application of stem cells are such as: Neurodegenerative conditions (MS,ALS, Parkinson’s, Stroke, Ocular disorders- Glaucoma, retinitis Pigmentosa (RP, Auto Immune Conditions (Lupus, MS,R. arthritis, Diabetes, etc, Viral Conditions (Hepatitis C and AIDS, Heart Disease, Adrenal Disorders, Injury(Nerve, Brain, etc, Anti aging (hair, skin, weight control, overall well being/preventive, Emotional disorders, Organ / Tissue Cancers, Blood cancers, Blood diseases

  8. Lung Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Sharon R. Pine

    2008-01-01

    Full Text Available Lung cancer remains a major cause of cancer-related lethality because of high incidence and recurrence in spite of significant advances in staging and therapies. Recent data indicates that stem cells situated throughout the airways may initiate cancer formation. These putative stem cells maintain protumorigenic characteristics including high proliferative capacity, multipotent differentiation, drug resistance and long lifespan relative to other cells. Stem cell signaling and differentiation pathways are maintained within distinct cancer types, and destabilization of this machinery may participate in maintenance of cancer stem cells. Characterization of lung cancer stem cells is an area of active research and is critical for developing novel therapies. This review summarizes the current knowledge on stem cell signaling pathways and cell markers used to identify the lung cancer stem cells.

  9. Stem cells in urology.

    Science.gov (United States)

    Aboushwareb, Tamer; Atala, Anthony

    2008-11-01

    The shortage of donors for organ transplantation has stimulated research on stem cells as a potential resource for cell-based therapy in all human tissues. Stem cells have been used for regenerative medicine applications in many organ systems, including the genitourinary system. The potential applications for stem cell therapy have, however, been restricted by the ethical issues associated with embryonic stem cell research. Instead, scientists have explored other cell sources, including progenitor and stem cells derived from adult tissues and stem cells derived from the amniotic fluid and placenta. In addition, novel techniques for generating stem cells in the laboratory are being developed. These techniques include somatic cell nuclear transfer, in which the nucleus of an adult somatic cell is placed into an oocyte, and reprogramming of adult cells to induce stem-cell-like behavior. Such techniques are now being used in tissue engineering applications, and some of the most successful experiments have been in the field of urology. Techniques to regenerate bladder tissue have reached the clinic, and exciting progress is being made in other areas, such as regeneration of the kidney and urethra. Cell therapy as a treatment for incontinence and infertility might soon become a reality. Physicians should be optimistic that regenerative medicine and tissue engineering will one day provide mainstream treatment options for urologic disorders.

  10. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    Directory of Open Access Journals (Sweden)

    Quanwen Liu

    2016-01-01

    Full Text Available In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bundles. The hair-cell-like cells exhibited rapid permeation of FM1-43FX. The whole-cell patch-clamp technique was used to measure the membrane currents of cells differentiated for 7 days on chicken utricle stromal cells and analyze the biophysical properties of the hair-cell-like cells by recording membrane properties of cells. The results suggested that the hair-cell-like cells derived from inner ear multipotent cells were functional following differentiation in an enabling environment.

  11. Pluripotent Stem Cells for Schwann Cell Engineering

    NARCIS (Netherlands)

    Ma, Ming-San; Boddeke, Erik; Copray, Sjef

    2015-01-01

    Tissue engineering of Schwann cells (SCs) can serve a number of purposes, such as in vitro SC-related disease modeling, treatment of peripheral nerve diseases or peripheral nerve injury, and, potentially, treatment of CNS diseases. SCs can be generated from autologous stem cells in vitro by recapitu

  12. Assessment of pancreas cells

    Science.gov (United States)

    Vanoss, C. J.

    1978-01-01

    Pancreatic islets were obtained from guinea pig pancreas by the collagenase method and kept alive in tissue culture prior to further studies. Pancreas cell morphology was studied by standard histochemical techniques using light microscopy. Preparative vertical electrophoresis-levitation of dispersed fetal guinea pig pancreas cells was conducted in phosphate buffer containing a heavy water (D20) gradient which does not cause clumping of cells or alter the osmolarity of the buffers. The faster migrating fractions tended to be enriched in beta-cell content. Alpha and delta cells were found to some degree in most fractions. A histogram showing the cell count distribution is included.

  13. Resident Peritoneal NK cells

    OpenAIRE

    Gonzaga, Rosemary; Matzinger, Polly; Perez-Diez, Ainhoa

    2011-01-01

    Here we describe a new population of NK cells that reside in the normal, un-inflamed peritoneal cavity. Phenotypically, they share some similarities with the small population of CD49b negative, CD27 positive immature splenic NK cells, and liver NK cells but differ in their expression of CD62L, TRAIL and EOMES. Functionally, the peritoneal NK cells resemble the immature splenic NK cells in their production of IFN-γ, GM-CSF and TNF-α and in the killing of YAC-1 target cells. We also found that ...

  14. Multipotent adult progenitor cell and stem cell plasticity

    OpenAIRE

    Jahagirdar, Balkrishna N; Verfaillie, Catherine

    2005-01-01

    Stem cells are defined by their biological function. A stem cell is an undifferentiated cell that self-renews to maintain the stem cell pool and at the single-cell level differentiates into more than one mature, functional cell. In addition, when transplanted, a stem cell should be capable of replacing a damaged organ or tissue for the lifetime of the recipient. Some would argue that stem cells should also be capable of functionally integrating into nondamaged tissues. Stem cells are critical...

  15. Epidermal Stem Cells

    Directory of Open Access Journals (Sweden)

    Osman Köse

    2015-03-01

    Full Text Available The epidermis is the outermost layer of the human skin and comprises a multilayered epithelium, the interfollicular epidermis, with associated hair follicles, sebaceous glands, and eccrine sweat glands. There are many origins of stem cells in the skin and skin appendages. These stem cells are localized in different part of the pilosebaseous units and also express many different genes. Epidermal stem cells in the pilosebaseous units not only ensure the maintenance of epidermal homeostasis and hair regeneration, but also contribute to repair of the epidermis after injury. In recent years, human induced pluripotent skin stem cells are produced from the epidermal cells such as keratinocytes, fibroblasts and melanocytes. These cells can be transdifferentiated to embriyonic stem cells. Human induced pluripotent stem cells have potential applications in cell replacement therapy and regenerative medicine. These cells provide a means to create valuable tools for basic research and may also produce a source of patient-matched cells for regenerative therapies. In this review, we aimed an overview of epidermal stem cells for better understanding their functions in the skin. Skin will be main organ for using the epidermal cells for regenerative medicine in near future.

  16. The cell cycle as a brake for β-cell regeneration from embryonic stem cells.

    Science.gov (United States)

    El-Badawy, Ahmed; El-Badri, Nagwa

    2016-01-13

    The generation of insulin-producing β cells from stem cells in vitro provides a promising source of cells for cell transplantation therapy in diabetes. However, insulin-producing cells generated from human stem cells show deficiency in many functional characteristics compared with pancreatic β cells. Recent reports have shown molecular ties between the cell cycle and the differentiation mechanism of embryonic stem (ES) cells, assuming that cell fate decisions are controlled by the cell cycle machinery. Both β cells and ES cells possess unique cell cycle machinery yet with significant contrasts. In this review, we compare the cell cycle control mechanisms in both ES cells and β cells, and highlight the fundamental differences between pluripotent cells of embryonic origin and differentiated β cells. Through critical analysis of the differences of the cell cycle between these two cell types, we propose that the cell cycle of ES cells may act as a brake for β-cell regeneration. Based on these differences, we discuss the potential of modulating the cell cycle of ES cells for the large-scale generation of functionally mature β cells in vitro. Further understanding of the factors that modulate the ES cell cycle will lead to new approaches to enhance the production of functional mature insulin-producing cells, and yield a reliable system to generate bona fide β cells in vitro.

  17. Regulatory T cells and B cells: implication on autoimmune diseases

    OpenAIRE

    Wang, Ping; Zheng, Song Guo

    2013-01-01

    The regulatory T (Treg) cells play an important role in the maintenance of homeostasis and the prevention of autoimmune diseases. Although most studies are focusing on the role of Treg cells in T cells and T cells-mediated diseases, these cells also directly affect B cells and other non-T cells. This manuscript updates the role of Treg cells on the B cells and B cell-mediated diseases. In addition, the mechanisms whereby Treg cells suppress B cell responses have been discussed.

  18. Toward 'SMART' stem cells.

    Science.gov (United States)

    Cheng, T

    2008-01-01

    Stem cell research is at the heart of regenerative medicine, which holds great promise for the treatment of many devastating disorders. However, in addition to hurdles posed by well-publicized ethical issues, this emerging field presents many biological challenges. What is a stem cell? How are embryonic stem cells different from adult stem cells? What are the physiological bases for therapeutically acceptable stem cells? In this editorial review, I will briefly discuss these superficially simple but actually rather complex issues that surround this fascinating cell type. The goal of this special issue on stem cells in Gene Therapy is to review some fundamental and critical aspects of current stem cell research that have translational potential. PMID:18046429

  19. Cell signaling review series

    Institute of Scientific and Technical Information of China (English)

    Aiming Lin; Zhenggang Liu

    2008-01-01

    @@ Signal transduction is pivotal for many, if not all, fundamental cellular functions including proliferation, differentiation, transformation and programmed cell death. Deregulation of cell signaling may result in certain types of cancers and other human diseases.

  20. Giant Cell Arteritis

    Science.gov (United States)

    Giant cell arteritis is a disorder that causes inflammation of your arteries, usually in the scalp, neck, and arms. ... arteries, which keeps blood from flowing well. Giant cell arteritis often occurs with another disorder called polymyalgia ...

  1. Sickle cell anemia.

    OpenAIRE

    ŘÍHOVÁ, Tereza

    2013-01-01

    This thesis is about the disease called sickle cell anemia, or drepanocytosis. In this thesis is described the history of the disease, pathophysiology, laboratory features, various clinical features, diferencial diagnosis, quality of life in sickle cell anemia and therapy.

  2. Sickle Cell Trait

    Science.gov (United States)

    ... About Us Information For... Media Policy Makers Sickle Cell Trait Language: English Español (Spanish) Recommend on Facebook ... the trait on to their children. How Sickle Cell Trait is Inherited If both parents have SCT, ...

  3. Sickle Cell Disease Quiz

    Science.gov (United States)

    ... About Us Information For... Media Policy Makers Sickle Cell Disease Quiz Language: English Español (Spanish) Recommend on ... True or False: Only African Americans get sickle cell disease. A True B False 2. True or ...

  4. Mammalian cell biology

    International Nuclear Information System (INIS)

    This section contains summaries of research on mechanisms of lethality and radioinduced changes in mammalian cell properties, new cell systems for the study of the biology of mutation and neoplastic transformation, and comparative properties of ionizing radiations

  5. Anaplastic Large Cell Lymphoma

    Science.gov (United States)

    Anaplastic Large Cell Lymphoma Overview Lymphoma is the most common blood cancer. The two main forms of lymphoma are ... organs, and can accumulate to form tumors. Anaplastic large cell lymphoma (ALCL) is arare type of NHL, ...

  6. What Are Islet Cells?

    Science.gov (United States)

    ... Video Be Part of the Cure Commitment to Stem Cell Research Exercise + Drug Therapy Tibi Creates Garment to Benefit ... Video Be Part of the Cure Commitment to Stem Cell Research Exercise + Drug Therapy Tibi Creates Garment to Benefit ...

  7. NIA Aging Cell Repository

    Data.gov (United States)

    Federal Laboratory Consortium — To facilitate aging research on cells in culture, the NIA provides support for the NIA Aging Cell Repository, located at the Coriell Institute for Medical Research...

  8. Sickle cell anemia

    Science.gov (United States)

    ... for avascular necrosis of the hip Surgery for eye problems Treatment for overuse or abuse of narcotic pain medicines Wound care for leg ulcers Bone marrow or stem cell transplants can cure sickle cell anemia, but this treatment ...

  9. Diagram of Cell to Cell Communication

    Science.gov (United States)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  10. STEM CELLS AND PROTEOMICS

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yong-ming; GUO Tian-nan; HUANG Shi-ang

    2006-01-01

    The distinctive features of proteomics are large-scale and high throughput. The key techniques of proteomics are two-dimensional gel electrophoresis, mass spectrometry and bioinformatics. Stem cell can differentiate into all kinds of cells, tissues and organs. There are many proteins and cytokines involved in the process of differentiation. Applying proteomics techniques to the research of the complex process of stem cell differentiation is of great importance to study the mechanism and applications of stem cell differentiation.

  11. Fish Stem Cell Cultures

    Directory of Open Access Journals (Sweden)

    Ni Hong, Zhendong Li, Yunhan Hong

    2011-01-01

    Full Text Available Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on “Fish Stem Cells and Nuclear Transfer”, we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  12. Skeletal (stromal) stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Kermani, Abbas Jafari; Zaher, Walid;

    2015-01-01

    Skeletal (marrow stromal) stem cells (BMSCs) are a group of multipotent cells that reside in the bone marrow stroma and can differentiate into osteoblasts, chondrocytes and adipocytes. Studying signaling pathways that regulate BMSC differentiation into osteoblastic cells is a strategy....../preadipocyte factor 1 (Dlk1/Pref-1), the Wnt co-receptor Lrp5 and intracellular kinases. This article is part of a Special Issue entitled: Stem Cells and Bone....

  13. Nanoelectrochemistry of mammalian cells

    OpenAIRE

    Sun, Peng; Laforge, François O.; Abeyweera, Thushara P.; Rotenberg, Susan A.; Carpino, James; Mirkin, Michael V.

    2008-01-01

    There is a significant current interest in development of new techniques for direct characterization of the intracellular redox state and high-resolution imaging of living cells. We used nanometer-sized amperometric probes in combination with the scanning electrochemical microscope (SECM) to carry out spatially resolved electrochemical experiments in cultured human breast cells. With the tip radius ≈1,000 times smaller than that of a cell, an electrochemical probe can penetrate a cell and tra...

  14. Optimizing stem cell culture.

    OpenAIRE

    van der Sanden, Boudewijn; Dhobb, Mehdi; Berger, François; Wion, Didier

    2010-01-01

    International audience Stem cells always balance between self-renewal and differentiation. Hence, stem cell culture parameters are critical and need to be continuously refined according to progress in our stem cell biology understanding and the latest technological developments. In the past few years, major efforts have been made to define more precisely the medium composition in which stem cells grow or differentiate. This led to the progressive replacement of ill-defined additives such a...

  15. Fish stem cell cultures.

    Science.gov (United States)

    Hong, Ni; Li, Zhendong; Hong, Yunhan

    2011-04-13

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  16. Prostate cancer stem cells

    OpenAIRE

    Tu, Shi-Ming; Lin, Sue-Hwa

    2011-01-01

    Stem cells have long been implicated in prostate glandular formation. The prostate undergoes regression after androgen deprivation and regeneration after testosterone replacement. Regenerative studies suggest that these cells are found in the proximal ducts and basal layer of the prostate. Many characteristics of prostate cancer indicate that it originates from stem cells. For example, the putative AR− status of prostate stem cells renders them inherently insensitive to androgen blockade ther...

  17. Lung Cancer Stem Cells

    OpenAIRE

    Pine, Sharon R.; Blair Marshall; Lyuba Varticovski

    2008-01-01

    Lung cancer remains a major cause of cancer-related lethality because of high incidence and recurrence in spite of significant advances in staging and therapies. Recent data indicates that stem cells situated throughout the airways may initiate cancer formation. These putative stem cells maintain protumorigenic characteristics including high proliferative capacity, multipotent differentiation, drug resistance and long lifespan relative to other cells. Stem cell signaling and differentiation p...

  18. Increased voltage photovoltaic cell

    Science.gov (United States)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  19. Aneuploidy in stem cells

    OpenAIRE

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to reality. However, as somatic cells might have accumulated various chromosomal abnormalities, including aneuploidies throughout their lives, the resulting IPSCs might no longer carry the perfect bluepri...

  20. Antitumor Immunity Produced by the Liver Kupffer Cells, NK Cells, NKT Cells, and CD8+ CD122+ T Cells

    OpenAIRE

    Shuhji Seki; Hiroyuki Nakashima; Masahiro Nakashima; Manabu Kinoshita

    2011-01-01

    Mouse and human livers contain innate immune leukocytes, NK cells, NKT cells, and macrophage-lineage Kupffer cells. Various bacterial components, including Toll-like receptor (TLR) ligands and an NKT cell ligand ( α -galactocylceramide), activate liver Kupffer cells, which produce IL-1, IL-6, IL-12, and TNF. IL-12 activates hepatic NK cells and NKT cells to produce IFN- γ , which further activates hepatic T cells, in turn activating phagocytosis and cytokine production by Kupffer cells in a p...

  1. Nanostructured Organic Solar Cells

    DEFF Research Database (Denmark)

    Radziwon, Michal Jędrzej; Rubahn, Horst-Günter; Madsen, Morten

    Recent forecasts for alternative energy generation predict emerging importance of supporting state of art photovoltaic solar cells with their organic equivalents. Despite their significantly lower efficiency, number of application niches are suitable for organic solar cells. This work reveals...... the principles of bulk heterojunction organic solar cells fabrication as well as summarises major differences in physics of their operation....

  2. Stem cell heterogeneity revealed

    DEFF Research Database (Denmark)

    Andersen, Marianne S; Jensen, Kim B

    2016-01-01

    The skin forms a protective, water-impermeable barrier consisting of heavily crosslinked epithelial cells. However, the specific role of stem cells in sustaining this barrier remains a contentious issue. A detailed analysis of the interfollicular epidermis now proposes a model for how a composite...... of cells with different properties are involved in its maintenance....

  3. Aneuploidy in stem cells

    NARCIS (Netherlands)

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to real

  4. Cell phones and cancer

    Science.gov (United States)

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of ...

  5. Mouse Leydig Tumor Cells

    Directory of Open Access Journals (Sweden)

    Bo-Syong Pan

    2011-01-01

    Full Text Available Cordycepin is a natural pure compound extracted from Cordyceps sinensis (CS. We have demonstrated that CS stimulates steroidogenesis in primary mouse Leydig cell and activates apoptosis in MA-10 mouse Leydig tumor cells. It is highly possible that cordycepin is the main component in CS modulating Leydig cell functions. Thus, our aim was to investigate the steroidogenic and apoptotic effects with potential mechanism of cordycepin on MA-10 mouse Leydig tumor cells. Results showed that cordycepin significantly stimulated progesterone production in dose- and time-dependent manners. Adenosine receptor (AR subtype agonists were further used to treat MA-10 cells, showing that A1, A 2A , A 2B , and A3, AR agonists could stimulate progesterone production. However, StAR promoter activity and protein expression remained of no difference among all cordycepin treatments, suggesting that cordycepin might activate AR, but not stimulated StAR protein to regulate MA-10 cell steroidogenesis. Meanwhile, cordycepin could also induce apoptotic cell death in MA-10 cells. Moreover, four AR subtype agonists induced cell death in a dose-dependent manner, and four AR subtype antagonists could all rescue cell death under cordycepin treatment in MA-10 cells. In conclusion, cordycepin could activate adenosine subtype receptors and simultaneously induce steroidogenesis and apoptosis in MA-10 mouse Leydig tumor cells.

  6. Adventures with Cell Phones

    Science.gov (United States)

    Kolb, Liz

    2011-01-01

    Teachers are finding creative ways to turn the basic cell phone from a digital distraction into a versatile learning tool. In this article, the author explains why cell phones are important in learning and suggests rather than banning them that they be integrated into learning. She presents activities that can be done on a basic cell phone with a…

  7. Dazlin' pluripotent stem cells

    NARCIS (Netherlands)

    Welling, M.A.

    2014-01-01

    Pluripotent embryonic stem cells (ESCs) can be isolated from the inner cell mass (ICM) of blastocyst embryos and differentiate into all three germ layers in vitro. However, despite their similar origin, mouse embryonic stem cells represent a more naïve ICM-like pluripotent state whereas human embryo

  8. Embryonic Stem Cell Markers

    Directory of Open Access Journals (Sweden)

    Lan Ma

    2012-05-01

    Full Text Available Embryonic stem cell (ESC markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES cells. Unfortunately, different cell types can share single or sometimes multiple markers; thus the main obstacle in the clinical application of ESC is to purify ES cells from other types of cells, especially tumor cells. Currently, the marker-based flow cytometry (FCM technique and magnetic cell sorting (MACS are the most effective cell isolating methods, and a detailed maker list will help to initially identify, as well as isolate ESCs using these methods. In the current review, we discuss a wide range of cell surface and generic molecular markers that are indicative of the undifferentiated ESCs. Other types of molecules, such as lectins and peptides, which bind to ESC via affinity and specificity, are also summarized. In addition, we review several markers that overlap with tumor stem cells (TSCs, which suggest that uncertainty still exists regarding the benefits of using these markers alone or in various combinations when identifying and isolating cells.

  9. astrocyte and astrocytoma cells

    DEFF Research Database (Denmark)

    Tfelt-Hansen, J.

    2008-01-01

    -transforming gene (PTTG), was found to be upregulated by the CaR in the H-500 cells, whereas calcium had no effect on PTTG expression in the U-87 astrocytoma cell line, but other proproliferative agents did upregulate PTTG in the U-87 cells. This makes PTTG a potential marker of malignancy and a therapeutic target...

  10. Advanced Cell Technology, Inc.

    Science.gov (United States)

    Caldwell, William M

    2007-03-01

    Advanced Cell Technology, Inc. (OTCBB: ACTC) is a biotechnology company applying novel human embryonic stem cell technologies in the emerging field of regenerative medicine. We believe that regenerative medicine has the potential to revolutionize the field by enabling scientists to produce human cells of any kind for use in a wide array of therapies.

  11. Battery cell module

    Energy Technology Data Exchange (ETDEWEB)

    Shambaugh, J.S.

    1981-11-23

    A modular lithium battery having a plurality of cells, having electrical connecting means connecting the cells to output terminals, and venting means for releasing discharge byproducts to a chemical scrubber is disclosed. Stainless steel cell casings are potted in an aluminum modular case with syntactic foam and epoxy. The wall thickness resulting is about 0.5 inches.

  12. Solar Photovoltaic Cells.

    Science.gov (United States)

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  13. STEM CELLS: Differentiated cells in a back-up role

    OpenAIRE

    Desai, Tushar J.; Krasnow, Mark A.

    2013-01-01

    Two independent studies show that, if push comes to shove, differentiated cells of the stomach and lung can act as adult stem cells generating various cell types of the tissue, including a pool of stem cells.

  14. MAPK uncouples cell cycle progression from cell spreading and cytoskeletal organization in cycling cells

    OpenAIRE

    Margadant, Coert; Cremers, Lobke; Sonnenberg, Arnoud; Boonstra, Johannes

    2012-01-01

    Integrin-mediated cytoskeletal tension supports growth-factor-induced proliferation, and disruption of the actin cytoskeleton in growth factor-stimulated cells prevents the re-expression of cyclin D and cell cycle re-entry from quiescence. In contrast to cells that enter the cell cycle from G0, cycling cells continuously express cyclin D, and are subject to major cell shape changes during the cell cycle. Here, we investigated the cell cycle requirements for cytoskeletal tension and cell sprea...

  15. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    OpenAIRE

    Quanwen Liu; Yi Shen; Jiarong Chen; Jie Ding; Zihua Tang; Cui Zhang; Jianling Chen; Liang Li; Ping Chen; Jinfu Wang

    2016-01-01

    In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bund...

  16. Dental pulp stem cells

    DEFF Research Database (Denmark)

    Ashri, N. Y.; Ajlan, S. A.; Aldahmash, Abdullah M.

    2015-01-01

    Inflammatory periodontal disease is a major cause of loss of tooth-supporting structures. Novel approaches for regeneration of periodontal apparatus is an area of intensive research. Periodontal tissue engineering implies the use of appropriate regenerative cells, delivered through a suitable...... scaffold, and guided through signaling molecules. Dental pulp stem cells have been used in an increasing number of studies in dental tissue engineering. Those cells show mesenchymal (stromal) stem cell-like properties including self-renewal and multilineage differentiation potentials, aside from...... an updated review on dental pulp stem cells and their applications in periodontal regeneration, in combination with different scaffolds and growth factors....

  17. Transparent ultraviolet photovoltaic cells.

    Science.gov (United States)

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future.

  18. Mechanics rules cell biology

    Directory of Open Access Journals (Sweden)

    Wang James HC

    2010-07-01

    Full Text Available Abstract Cells in the musculoskeletal system are subjected to various mechanical forces in vivo. Years of research have shown that these mechanical forces, including tension and compression, greatly influence various cellular functions such as gene expression, cell proliferation and differentiation, and secretion of matrix proteins. Cells also use mechanotransduction mechanisms to convert mechanical signals into a cascade of cellular and molecular events. This mini-review provides an overview of cell mechanobiology to highlight the notion that mechanics, mainly in the form of mechanical forces, dictates cell behaviors in terms of both cellular mechanobiological responses and mechanotransduction.

  19. Internalization of NK cells into tumor cells requires ezrin and leads to programmed cell-in-cell death

    Institute of Scientific and Technical Information of China (English)

    Shan Wang; Zhen Guo; Peng Xia; Tingting Liu; Jufang Wang; Shan Li; Lihua Sun; Jianxin Lu; Qian Wen; Mingqian Zhou; Li Ma; Xia Ding; Xiaoning Wang; Xuebiao Yao

    2009-01-01

    Cytotoxic lymphocytes are key players in the orchestration of immune response and elimination of defective cells. We have previously reported that natural killer (NK) cells enter target tumor cells, leading to either target cell death or self-destruction within tumor cells. However, it has remained elusive as to the fate of NK cells after internaliza-tion and whether the heterotypic cell-in-cell process is different from that of the homotypic cell-in-cell event recently named entosis. Here, we show that NK cells undergo a cell-in-cell process with the ultimate fate of apoptosis within tumor cells and reveal that the internalization process requires the actin cytoskeletal regulator, ezrin. To visualize how NK cells enter into tumor cells, we carried out real-time dual color imaging analyses of NK cell internalization into tumor cells. Surprisingly, most NK cells commit to programmed cell death after their entry into tumor cells, which is distinctively different from entosis observed in the homotypic cell-in-cell process. The apoptotic cell death of the internalized NK cells was evident by activation of caspase 3 and DNA fragmentation. Furthermore, NK cell death after internalization is attenuated by the caspase inhibitor, Z-VAD-FMK, confirming apoptosis as the mode of NK cell death within tumor cells. To determine protein factors essential for the entry of NK cells into tumor cells, we car-ried out siRNA-based knockdown analysis and discovered a critical role of ezrin in NK cell internalization. Impor-tantly, PKA-mediated phosphorylation of ezrin promotes the NK cell internalization process. Our findings suggest a novel regulatory mechanism by which ezrin governs NK cell internalization into tumor cells.

  20. Fuel Cell/Electrochemical Cell Voltage Monitor

    Science.gov (United States)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  1. Parameterization of solar cells

    Science.gov (United States)

    Appelbaum, J.; Chait, A.; Thompson, D.

    1992-10-01

    The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided by modeling the cell using an equivalent electrical circuit, in which the parameters involved are related to the physical phenomena in the device. These analytical models may be represented by a double exponential I-V characteristic with seven parameters, by a double exponential model with five parameters, or by a single exponential equation with four or five parameters. In this article we address issues concerning methodologies for the determination of solar cell parameters based on measured data points of the I-V characteristic, and introduce a procedure for screening of solar cells for arrays. We show that common curve fitting techniques, e.g., least squares, may produce many combinations of parameter values while maintaining a good fit between the fitted and measured I-V characteristics of the cell. Therefore, techniques relying on curve fitting criteria alone cannot be directly used for cell parameterization. We propose a consistent procedure which takes into account the entire set of parameter values for a batch of cells. This procedure is based on a definition of a mean cell representing the batch, and takes into account the relative contribution of each parameter to the overall goodness of fit. The procedure is demonstrated on a batch of 50 silicon cells for Space Station Freedom.

  2. T cell subpopulations.

    Science.gov (United States)

    Romagnani, Sergio

    2014-01-01

    The role of allergen-specific CD4+ effector type 2 helper (Th2) cells in the pathogenesis of allergic disorders is an established fact. Th2 cells produce interleukin (IL)-4 and IL-13, which induce immunoglobulin E production by B cells, and IL-5 that allows recruitment of eosinophils. Two main mechanisms control the Th2-mediated allergic inflammation: immune deviation (or Th1 redirection) and immune regulation. Regulatory T (Treg) cells exhibit a CD4+ phenotype and include Foxp3-positive thymic and induced Tregs, as well as Foxp3-negative IL-10-producing cells. Both immune deviation and immune regulation evoked by the maternal and newborn microbial environment probably operate in preventing allergen-specific Th2 responses. However, microbe-related protection from allergy seems to mainly depend on epigenetically controlled acetylation of the IFNG promoter of CD4+ T cells. Even Th17 and Th9 cells, as well as invariant NKT cells, have been implicated in the pathogenesis of allergic disorders, but their role is certainly more limited. Recently, innate lymphoid type 2 cells (ILC2) have been found to be able to produce high amounts of IL-5 and IL-13 in response to stimulation with IL-25 and IL-33 produced by non-immune cells. Together with Th2 cells, ILC2 may contribute to the induction and maintenance of allergic inflammation. PMID:24925396

  3. Cell adhesion in regulation of asymmetric stem cell division

    OpenAIRE

    Yamashita, Yukiko M

    2010-01-01

    Adult stem cells inevitably communicate with their cellular neighbors within the tissues they sustain. Indeed, such communication, particularly with components of the stem cell niche, is essential for many aspects of stem cell behavior, including the maintenance of stem cell identity and asymmetric cell division. Cell adhesion mediates this communication by placing stem cells in close proximity to the signaling source and by providing a polarity cue that orients stem cells. Here, I review the...

  4. Cell biology. Metabolic control of cell death.

    Science.gov (United States)

    Green, Douglas R; Galluzzi, Lorenzo; Kroemer, Guido

    2014-09-19

    Beyond their contribution to basic metabolism, the major cellular organelles, in particular mitochondria, can determine whether cells respond to stress in an adaptive or suicidal manner. Thus, mitochondria can continuously adapt their shape to changing bioenergetic demands as they are subjected to quality control by autophagy, or they can undergo a lethal permeabilization process that initiates apoptosis. Along similar lines, multiple proteins involved in metabolic circuitries, including oxidative phosphorylation and transport of metabolites across membranes, may participate in the regulated or catastrophic dismantling of organelles. Many factors that were initially characterized as cell death regulators are now known to physically or functionally interact with metabolic enzymes. Thus, several metabolic cues regulate the propensity of cells to activate self-destructive programs, in part by acting on nutrient sensors. This suggests the existence of "metabolic checkpoints" that dictate cell fate in response to metabolic fluctuations. Here, we discuss recent insights into the intersection between metabolism and cell death regulation that have major implications for the comprehension and manipulation of unwarranted cell loss.

  5. Enteroendocrine cell types revisited

    DEFF Research Database (Denmark)

    Engelstoft, Maja S; Egerod, Kristoffer Lihme; Lund, Mari L;

    2013-01-01

    The GI-tract is profoundly involved in the control of metabolism through peptide hormones secreted from enteroendocrine cells scattered throughout the gut mucosa. A large number of recently generated transgenic reporter mice have allowed for direct characterization of biochemical and cell...... biological properties of these previously highly elusive enteroendocrine cells. In particular the surprisingly broad co-expression of six functionally related hormones in the intestinal enteroendocrine cells indicates that it should be possible to control not only the hormone secretion but also the type...... and number of enteroendocrine cells. However, this will require a more deep understanding of the factors controlling differentiation, gene expression and specification of the enteroendocrine cells during their weekly renewal from progenitor cells in the crypts of the mucosa....

  6. Mammary gland stem cells

    DEFF Research Database (Denmark)

    Fridriksdottir, Agla J R; Petersen, Ole W; Rønnov-Jessen, Lone

    2011-01-01

    Distinct subsets of cells, including cells with stem cell-like properties, have been proposed to exist in normal human breast epithelium and breast carcinomas. The cellular origins of epithelial cells contributing to gland development, tissue homeostasis and cancer are, however, still poorly...... understood. The mouse is a widely used model of mammary gland development, both directly by studying the mouse mammary epithelial cells themselves and indirectly, by studying development, morphogenesis, differentiation and carcinogenesis of xenotransplanted human breast epithelium in vivo. While in early...... studies, human or mouse epithelium was implanted as fragments into the mouse gland, more recent technical progress has allowed the self-renewal capacity and differentiation potential of distinct cell populations or even individual cells to be interrogated. Here, we review and discuss similarities...

  7. Cell and Tissue Engineering

    CERN Document Server

    2012-01-01

    Cell and Tissue Engineering” introduces the principles and new approaches in cell and tissue engineering. It includes both the fundamentals and the current trends in cell and tissue engineering, in a way useful both to a novice and an expert in the field. The book is composed of 13 chapters all of which are written by the leading experts. It is organized to gradually assemble an insight in cell and tissue function starting form a molecular nano-level, extending to a cellular micro-level and finishing at the tissue macro-level. In specific, biological, physiological, biophysical, biochemical, medical, and engineering aspects are covered from the standpoint of the development of functional substitutes of biological tissues for potential clinical use. Topics in the area of cell engineering include cell membrane biophysics, structure and function of the cytoskeleton, cell-extracellular matrix interactions, and mechanotransduction. In the area of tissue engineering the focus is on the in vitro cultivation of ...

  8. Peripheral giant cell granuloma

    Directory of Open Access Journals (Sweden)

    Padam Narayan Tandon

    2012-01-01

    Full Text Available Peripheral giant cell granuloma or the so-called "giant cell epulis" is the most common oral giant cell lesion. It normally presents as a soft tissue purplish-red nodule consisting of multinucleated giant cells in a background of mononuclear stromal cells and extravasated red blood cells. This lesion probably does not represent a true neoplasm, but rather may be reactive in nature, believed to be stimulated by local irritation or trauma, but the cause is not certainly known. This article reports a case of peripheral giant cell granuloma arising at the maxillary anterior region in a 22-year-old female patient. The lesion was completely excised to the periosteum level and there is no residual or recurrent swelling or bony defect apparent in the area of biopsy after a follow-up period of 6 months.

  9. T Cells Going Innate.

    Science.gov (United States)

    Seyda, Midas; Elkhal, Abdallah; Quante, Markus; Falk, Christine S; Tullius, Stefan G

    2016-08-01

    Natural killer (NK) cell receptors (NKRs) play a crucial role in the homeostasis of antigen-experienced T cells. Indeed, prolonged antigen stimulation may induce changes in the receptor repertoire of T cells to a profile that features NKRs. Chronic antigen exposure, at the same time, has been shown to trigger the loss of costimulatory CD28 molecules with recently reported intensified antigen thresholds of antigen-experienced CD8(+) T cells. In transplantation, NKRs have been shown to assist allograft rejection in a CD28-independent fashion. We discuss here a role for CD28-negative T cells that have acquired the competency of the NKR machinery, potentially promoting allorecognition either through T cell receptor (TCR) crossreactivity or independently from TCR recognition. Collectively, NKRs can bring about innate-like T cells by providing alternative costimulatory pathways that gain relevance in chronic inflammation, potentially leading to resistance to CD28-targeting immunosuppressants. PMID:27402226

  10. Information on Stem Cell Research

    Science.gov (United States)

    ... Enhancing Diversity Find People About NINDS Information on Stem Cell Research Research @ NINDS Stem Cell Highlights Submit a hESC ... found here: Human Induced Pluripotent Stem Cells NINDS Stem Cell Research on Campus The Intramural Research Program of NINDS ...

  11. Nevoid Basal Cell Carcinoma Syndrome

    Science.gov (United States)

    ... Nevoid Basal Cell Carcinoma Syndrome Request Permissions Nevoid Basal Cell Carcinoma Syndrome Approved by the Cancer.Net Editorial Board , 04/2016 What is Nevoid Basal Cell Carcinoma Syndrome? Nevoid Basal Cell Carcinoma Syndrome (NBCCS) is ...

  12. Nestin(+) cells direct inflammatory cell migration in atherosclerosis.

    Science.gov (United States)

    Del Toro, Raquel; Chèvre, Raphael; Rodríguez, Cristina; Ordóñez, Antonio; Martínez-González, José; Andrés, Vicente; Méndez-Ferrer, Simón

    2016-01-01

    Atherosclerosis is a leading death cause. Endothelial and smooth muscle cells participate in atherogenesis, but it is unclear whether other mesenchymal cells contribute to this process. Bone marrow (BM) nestin(+) cells cooperate with endothelial cells in directing monocyte egress to bloodstream in response to infections. However, it remains unknown whether nestin(+) cells regulate inflammatory cells in chronic inflammatory diseases, such as atherosclerosis. Here, we show that nestin(+) cells direct inflammatory cell migration during chronic inflammation. In Apolipoprotein E (ApoE) knockout mice fed with high-fat diet, BM nestin(+) cells regulate the egress of inflammatory monocytes and neutrophils. In the aorta, nestin(+) stromal cells increase ∼30 times and contribute to the atheroma plaque. Mcp1 deletion in nestin(+) cells-but not in endothelial cells only- increases circulating inflammatory cells, but decreases their aortic infiltration, delaying atheroma plaque formation and aortic valve calcification. Therefore, nestin expression marks cells that regulate inflammatory cell migration during atherosclerosis. PMID:27586429

  13. PEROVSKITE SOLAR CELLS (REVIEW ARTICLE)

    OpenAIRE

    Benli, Deniz Ahmet

    2015-01-01

    A solar cell is a device that converts sunlight into electricity. There are different types of solar cells but this report mainly focuses on a type of new generation solar cell that has the name organo-metal halide perovskite, shortly perovskite solar cells. In this respect, the efficiency of power conversion is taken into account to replace the dominancy of traditional and second generation solar cell fields by perovskite solar cells. Perovskite solar cell is a type of solar cell including a...

  14. Introduction to Stem Cell Therapy

    OpenAIRE

    Biehl, Jesse K.; Russell, Brenda

    2009-01-01

    Stem cells have the ability to differentiate into specific cell types. The two defining characteristics of a stem cell are perpetual self-renewal and the ability to differentiate into a specialized adult cell type. There are two major classes of stem cells: pluripotent that can become any cell in the adult body, and multipotent that are restricted to becoming a more limited population of cells. Cell sources, characteristics, differentiation and therapeutic applications are discussed. Stem cel...

  15. Simple Cell Balance Circuit

    Science.gov (United States)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  16. B cells help alloreactive T cells differentiate into memory T cells1

    OpenAIRE

    Ng, Yue-Harn; Oberbarnscheidt, Martin H.; Chandramoorthy, Harish Chinna Konda; Hoffman, Rosemary; Chalasani, Geetha

    2010-01-01

    B cells are recognized as effector cells in allograft rejection that are dependent upon T cell help to produce alloantibodies causing graft injury. It is not known if B cells can also help T cells differentiate into memory cells in the alloimmune response. We found that in B cell-deficient hosts, differentiation of alloreactive T cells into effectors was intact whereas their development into memory T cells was impaired. To test if B cell help for T cells was required for their continued diffe...

  17. Mechanical plasticity of cells

    Science.gov (United States)

    Bonakdar, Navid; Gerum, Richard; Kuhn, Michael; Spörrer, Marina; Lippert, Anna; Schneider, Werner; Aifantis, Katerina E.; Fabry, Ben

    2016-10-01

    Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic deformation response. Moreover, the plastic deformation is a constant fraction of the total cell deformation and originates from bond ruptures within the cytoskeleton. A simple extension of the prevailing viscoelastic power-law response theory with a plastic element correctly predicts the cell behaviour under cyclic loading. Our findings show that plastic energy dissipation during cell deformation is tightly linked to elastic cytoskeletal stresses, which suggests the existence of an adaptive mechanism that protects the cell against mechanical damage.

  18. Cytoskeleton and Cell Motility

    CERN Document Server

    Risler, Thomas

    2011-01-01

    The present article is an invited contribution to the Encyclopedia of Complexity and System Science, Robert A. Meyers Ed., Springer New York (2009). It is a review of the biophysical mechanisms that underly cell motility. It mainly focuses on the eukaryotic cytoskeleton and cell-motility mechanisms. Bacterial motility as well as the composition of the prokaryotic cytoskeleton is only briefly mentioned. The article is organized as follows. In Section III, I first present an overview of the diversity of cellular motility mechanisms, which might at first glance be categorized into two different types of behaviors, namely "swimming" and "crawling". Intracellular transport, mitosis - or cell division - as well as other extensions of cell motility that rely on the same essential machinery are briefly sketched. In Section IV, I introduce the molecular machinery that underlies cell motility - the cytoskeleton - as well as its interactions with the external environment of the cell and its main regulatory pathways. Sec...

  19. Induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Siddhartha Bhowmik; LI Yong

    2011-01-01

    Induced pluripotent stem (iPS) cells are a recent development which has brought a promise of great therapeutic values. The previous technique of somatic cell nuclear transfer (SCNT) has been ineffective in humans. Recent discoveries show that human fibroblasts can be reprogrammed by a transient over expression of a small number of genes; they can undergo induced pluripotency. iPS were first produced in 2006. By 2008, work was underway to remove the potential oncogenes from their structure. In 2009, protein iPS (piPS) cells were discovered. Surface markers and reporter genes play an important role in stem cell research. Clinical applications include generation of self renewing stem cells, tissue replacement and many more. Stem cell therapy has the ability to dramatically change the treatment of human diseases.

  20. NCAM regulates cell motility

    DEFF Research Database (Denmark)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna;

    2002-01-01

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells...... independently of homophilic NCAM interactions. Expression of the transmembrane 140 kDa isoform of NCAM (NCAM-140) caused a significant reduction in cellular motility, probably through interference with factors regulating cellular attachment, as NCAM-140-expressing cells exhibited a decreased attachment...... to a fibronectin substratum compared with NCAM-negative cells. Ectopic expression of the cytoplasmic part of NCAM-140 also inhibited cell motility, presumably via the non-receptor tyrosine kinase p59(fyn) with which NCAM-140 interacts. Furthermore, we showed that the extracellular part of NCAM acted as a paracrine...

  1. Myoepithelial cells in pathology

    Directory of Open Access Journals (Sweden)

    N Balachander

    2015-01-01

    Full Text Available Myoepithelial cells are a normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. Microscopically myoepithelial cells are thin and spindle-shaped and ultrastructurally they possess a number of Cytoplasmic processes that extend between and over the acinar and ductal-lining cells, and they show features of both smooth muscle and epithelium. They play a vital role during expulsion of saliva and regulates the electrolytic exchange. They also perform as tumor suppressors and are considered to play a very important role in differentiation of various salivary gland tumors and help in the diagnosis of tumors. Neoplastic myoepithelial cells in both benign and malignant tumors can take numerous forms including epithelioid, plasmacytoid, spindle and clear cell variant, and this variability largely accounts for difficulties in histopathological diagnosis.

  2. Mammalian cell biology

    International Nuclear Information System (INIS)

    Studies of the action of N-ethylmaleimide (NEM), as an inhibitor of repair of x radioinduced injuries were extended from synchronous Chinese hamster cells to synchronous human HeLa cells. These studies showed a similar mode of action in both cell types lending support to the notion that conclusions may be extracted from such observations that are of fairly general applicability to mammalian cells. Radiation studies with NEM are being extended to hypoxic cells to inquire if NEM is effective relative to oxygen-independent damage. Observations relative to survival, DNA synthesis, and DNA strand elongation resulting from the addition products to DNA when cells were exposed to near uv in the presence of psoralen were extended. (U.S.)

  3. Fish germ cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Fish, like many other animals, have two major cell lineages, namely the germline and soma. The germ-soma separation is one of the earliest events of embryonic development. Germ cells can be specifically labeled and isolated for culture and transplan-tation, providing tools for reproduction of endangered species in close relatives, such as surrogate production of trout in salmon. Haploid cell cultures, such as medaka haploid embryonic stem cells have recently been obtained, which are capable of mimicking sperm to produce fertile offspring, upon nuclear being directly transferred into normal eggs. Such fish originated from a mosaic oocyte that had a haploid meiotic nucleus and a transplanted haploid mitotic cell culture nucleus. The first semi-cloned fish is Holly. Here we review the current status and future directions of understanding and manipulating fish germ cells in basic research and reproductive technology.

  4. Basal cell carcinoma of the skin with areas of squamous cell carcinoma: a basosquamous cell carcinoma?

    OpenAIRE

    Faria, J.

    1985-01-01

    The diagnosis of basosquamous cell carcinoma is controversial. A review of cases of basal cell carcinoma showed 23 cases that had conspicuous areas of squamous cell carcinoma. This was distinguished from squamous differentiation and keratotic basal cell carcinoma by a comparative study of 40 cases of compact lobular and 40 cases of keratotic basal cell carcinoma. Areas of intermediate tumour differentiation between basal cell and squamous cell carcinoma were found. Basal cell carcinomas with ...

  5. Traction in smooth muscle cells varies with cell spreading

    Science.gov (United States)

    Tolic-Norrelykke, Iva Marija; Wang, Ning

    2005-01-01

    Changes in cell shape regulate cell growth, differentiation, and apoptosis. It has been suggested that the regulation of cell function by the cell shape is a result of the tension in the cytoskeleton and the distortion of the cell. Here we explore the association between cell-generated mechanical forces and the cell morphology. We hypothesized that the cell contractile force is associated with the degree of cell spreading, in particular with the cell length. We measured traction fields of single human airway smooth muscle cells plated on a polyacrylamide gel, in which fluorescent microbeads were embedded to serve as markers of gel deformation. The traction exerted by the cells at the cell-substrate interface was determined from the measured deformation of the gel. The traction was measured before and after treatment with the contractile agonist histamine, or the relaxing agonist isoproterenol. The relative increase in traction induced by histamine was negatively correlated with the baseline traction. On the contrary, the relative decrease in traction due to isoproterenol was independent of the baseline traction, but it was associated with cell shape: traction decreased more in elongated than in round cells. Maximum cell width, mean cell width, and projected area of the cell were the parameters most tightly coupled to both baseline and histamine-induced traction in this study. Wide and well-spread cells exerted larger traction than slim cells. These results suggest that cell contractility is controlled by cell spreading.

  6. Microbial fuel cells

    International Nuclear Information System (INIS)

    Microbial fuel cells (MFC) are a promising technology for sustainable production of alternative energy and waste treatment. A microbial fuel cell transformation chemical energy in the chemical bonds in organic compounds to electrical energy through catalytic reactions of microorganisms under anaerobic conditions. It has been known for many years that it is possible to generate electricity directly by using bacteria to break down organic substrates. Key words: microbial fuel cells (MFC), biosensor, wastewater treatment

  7. Epidermal Stem Cells

    OpenAIRE

    Osman Köse

    2015-01-01

    The epidermis is the outermost layer of the human skin and comprises a multilayered epithelium, the interfollicular epidermis, with associated hair follicles, sebaceous glands, and eccrine sweat glands. There are many origins of stem cells in the skin and skin appendages. These stem cells are localized in different part of the pilosebaseous units and also express many different genes. Epidermal stem cells in the pilosebaseous units not only ensure the maintenance of epidermal homeostasis and ...

  8. Liver Cancer Stem Cells

    OpenAIRE

    Sameh Mikhail; Aiwu Ruth He

    2011-01-01

    Hepatocellular carcinoma is the most common primary malignancy of the liver in adults. It is also the fifth most common solid cancer worldwide and the third leading cause of cancer-related death. Recent research supports that liver cancer is a disease of adult stem cells. From the models of experimental hepatocarcinogenesis, there may be at least three distinct cell lineages with progenitor properties susceptible to neoplastic transformation. Identification of specific cell surface markers fo...

  9. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  10. Cell therapy of pseudarthrosis

    OpenAIRE

    Bastos Filho, Ricardo; Lermontov, Simone; Borojevic, Radovan; Schott, Paulo Cezar; Gameiro, Vinicius Schott; José Mauro GRANJEIRO

    2012-01-01

    Objective To assess the safety and efficiency of cell therapy for pseudarthrosis. Implant of the bone marrow aspirate was compared to mononuclear cells purified extemporaneously using the Sepax® equipment. Methods Six patients with nonunion of the tibia or femur were treated. Four received a percutaneous infusion of autologous bone marrow aspirated from the iliac crest, and two received autologous bone marrow mononuclear cells separated from the aspirate with the Sepax®. The primary fixation ...

  11. Chiaroscuro hematopoietic stem cell.

    OpenAIRE

    Quesenberry, P.; Habibian, M. (PhD); Dooner, M; Zhong, S.; Reilly, J; Peters, S.; De Becker, P; Grimaldi, C.; Carlson, J; REDDY, P; Nilsson, S.; Stewart, F. M.

    1998-01-01

    These observations suggest several immediate clinical strategies. In gene therapy, approaches could be targeted to obtain cycling of hematopoietic stem cells and gene-carrying retrovirus vector integration followed by engraftment at an appropriate time interval which favors engraftment. The same type of approach can be utilized for stem cell expansion approaches. Alternatively marrow or peripheral stem cell engraftment can be obtained with minimal to no toxicity in allochimeric strategies in ...

  12. Stem cell myths

    OpenAIRE

    Magnus, Tim; Liu, Ying; Parker, Graham C.; Rao, Mahendra S.

    2007-01-01

    Stem cells, although difficult to define, hold great promise as tools for understanding development and as therapeutic agents. However, as with any new field, uncritical enthusiasm can outstrip reality. In this review, we have listed nine common myths that we believe affect our approach to evaluating stem cells for therapy. We suggest that careful consideration needs to be given to each of these issues when evaluating a particular cell for its use in therapy. Data need to be collected and rep...

  13. Cancer stem cell metabolism

    OpenAIRE

    Peiris-Pagès, Maria; Martinez-Outschoorn, Ubaldo E.; Pestell, Richard G.; Sotgia, Federica; Lisanti, Michael P

    2016-01-01

    Cancer is now viewed as a stem cell disease. There is still no consensus on the metabolic characteristics of cancer stem cells, with several studies indicating that they are mainly glycolytic and others pointing instead to mitochondrial metabolism as their principal source of energy. Cancer stem cells also seem to adapt their metabolism to microenvironmental changes by conveniently shifting energy production from one pathway to another, or by acquiring intermediate metabolic phenotypes. Deter...

  14. Lung Stem cell biology

    OpenAIRE

    Ardhanareeswaran, Karthikeyan; Mirotsou, Maria

    2013-01-01

    Over the past few years new insights have been added to the study of stem cells in the adult lung. The exploration of the endogenous lung progenitors as well as the study of exogenously delivered stem cell populations holds promise for advancing our understanding of the biology of lung repair mechanisms. Moreover, it opens new possibilities for the use of stem cell therapy for the development of regenerative medicine approaches for the treatment of lung disease. Here, we discuss the main type...

  15. Gastric Cancer Stem Cells

    OpenAIRE

    Takaishi, Shigeo; Okumura, Tomoyuki; Timothy C Wang

    2008-01-01

    Cancer stem cells are defined as the unique subpopulation in the tumors that possess the ability to initiate tumor growth and sustain self-renewal as well as metastatic potential. Accumulating evidence in recent years strongly indicate the existence of cancer stem cells in solid tumors of a wide variety of organs. In this review, we will discuss the possible existence of a gastric cancer stem cell. Our recent data suggest that a subpopulation with a defined marker shows spheroid colony format...

  16. APUD cells in teratomas.

    OpenAIRE

    Bosman, F. T.; Louwerens, J. W.

    1981-01-01

    The origin of the endocrine cells in the respiratory tract and the gastrointestinal tract is still a matter of debate. In the original concept of the amine precursor uptake and decarboxylation (APUD) system, all APUD cells were considered to be derived from the neural crest. More recently it has been proposed that the APUD cell types of the gastrointestinal and respiratory tracts originate from neuroendocrine-programmed ectoblast. Still other investigators have reported observations that favo...

  17. Hair cell ribbon synapses

    OpenAIRE

    Moser, Tobias; Brandt, Andreas; Lysakowski, Anna

    2006-01-01

    Hearing and balance rely on the faithful synaptic coding of mechanical input by the auditory and vestibular hair cells of the inner ear. Mechanical deflection of their stereocilia causes the opening of mechanosensitive channels, resulting in hair cell depolarization, which controls the release of glutamate at ribbon-type synapses. Hair cells have a compact shape with strong polarity. Mechanoelectrical transduction and active membrane turnover associated with stereociliar renewal dominate the ...

  18. Systems cell biology.

    Science.gov (United States)

    Mast, Fred D; Ratushny, Alexander V; Aitchison, John D

    2014-09-15

    Systems cell biology melds high-throughput experimentation with quantitative analysis and modeling to understand many critical processes that contribute to cellular organization and dynamics. Recently, there have been several advances in technology and in the application of modeling approaches that enable the exploration of the dynamic properties of cells. Merging technology and computation offers an opportunity to objectively address unsolved cellular mechanisms, and has revealed emergent properties and helped to gain a more comprehensive and fundamental understanding of cell biology.

  19. Nanocrystal Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ilan

    2006-12-15

    This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

  20. Mesenchymal stem cells.

    Science.gov (United States)

    Ding, Dah-Ching; Shyu, Woei-Cherng; Lin, Shinn-Zong

    2011-01-01

    Stem cells have two features: the ability to differentiate along different lineages and the ability of self-renewal. Two major types of stem cells have been described, namely, embryonic stem cells and adult stem cells. Embryonic stem cells (ESC) are obtained from the inner cell mass of the blastocyst and are associated with tumorigenesis, and the use of human ESCs involves ethical and legal considerations. The use of adult mesenchymal stem cells is less problematic with regard to these issues. Mesenchymal stem cells (MSCs) are stromal cells that have the ability to self-renew and also exhibit multilineage differentiation. MSCs can be isolated from a variety of tissues, such as umbilical cord, endometrial polyps, menses blood, bone marrow, adipose tissue, etc. This is because the ease of harvest and quantity obtained make these sources most practical for experimental and possible clinical applications. Recently, MSCs have been found in new sources, such as menstrual blood and endometrium. There are likely more sources of MSCs waiting to be discovered, and MSCs may be a good candidate for future experimental or clinical applications. One of the major challenges is to elucidate the mechanisms of differentiation, mobilization, and homing of MSCs, which are highly complex. The multipotent properties of MSCs make them an attractive choice for possible development of clinical applications. Future studies should explore the role of MSCs in differentiation, transplantation, and immune response in various diseases. PMID:21396235

  1. Red cell enzymes.

    Science.gov (United States)

    Paniker, N V

    1975-03-01

    As compared to other cells of the body, the mammalian red cell has one of the simplest structural organizations. As a result, this cell has been extensively used in studies involving the structure, function, and integrity of cell membranes as well as cytoplasmic events. Additionally, the metabolic activities of the red blood cell are also relatively simple. During the past quarter century or so, an ocean of knowledge has been gathered on various aspects of red cell metabolism and function. The fields of enzymes, hemoglobin, membrane, and metabolic products comprise the major portion of this knowledge. These advances have made valuable contributions to biochemistry and medicine. Despite these favorable aspects of this simple, anucleated cell, it must be conceded that our knowledge about the red cell is far from complete. We are still in the dark concerning the mechanism involved in several aspects of its membrane, hemoglobin, enzymes, and a large number of other constituents. For example, a large number of enzymes with known catalytic activity but with unknown function have eluded investigators despite active pursuit. This review will be a consolidation of our present knowledge of human red cell enzymes, with particular reference to their usefulness in the diagnosis and therapy of disease. Owing to the multitude of publications by prominent investigators on each of the approximately 50 enzymes discussed in this review, it was impossible to cite a majority of them.

  2. Littoral Cells 2005

    Data.gov (United States)

    California Department of Resources — Littoral cells along the California Coast. Originally digitized by Melanie Coyne from the Assessment and Atlas of Shoreline Erosion Along the California Coast...

  3. HTPEM Fuel Cell Impedance

    DEFF Research Database (Denmark)

    Vang, Jakob Rabjerg

    potentially play an important role in the energy system of the future. One of the fuel cell technologies, that receives much attention from the Danish scientific community is high temperature proton exchange membrane (HTPEM) fuel cells based on polybenzimidazole (PBI) with phosphoric acid as proton conductor...... cells through experimental studies and mathematical modelling. These studies all revolve around the electrochemical impedance spectroscopy (EIS) characterisation method. EIS is performed by applying a sinusoidal current or voltage signal to the fuel cell and calculating the impedance from the response...

  4. [Endothelial cell adhesion molecules].

    Science.gov (United States)

    Ivanov, A N; Norkin, I A; Puchin'ian, D M; Shirokov, V Iu; Zhdanova, O Iu

    2014-01-01

    The review presents current data concerning the functional role of endothelial cell adhesion molecules belonging to different structural families: integrins, selectins, cadherins, and the immunoglobulin super-family. In this manuscript the regulatory mechanisms and factors of adhesion molecules expression and distribution on the surface of endothelial cells are discussed. The data presented reveal the importance of adhesion molecules in the regulation of structural and functional state of endothelial cells in normal conditions and in pathology. Particular attention is paid to the importance of these molecules in the processes of physiological and pathological angiogenesis, regulation of permeability of the endothelial barrier and cell transmigration.

  5. Multiple granular cell tumor.

    Science.gov (United States)

    Jones, J K; Kuo, T T; Griffiths, C M; Itharat, S

    1980-10-01

    Eleven cases of granular cell tumor were reviewed. In two of the cases multiple sites of involvement were seen. The tumor occurred in the oral cavity in both of these cases and each was initially wrongly diagnosed as squamous cell carcinoma. The most common site was the subcutaneous tissue (nine patients) and the tongue was involved in three cases. In one patient the parotid gland was involved. Eight of the patients were females and three were males; seven were black and four were white. The importance of differentiating between squamous cell carcinoma and granular cell tumor is stressed, as is the need for a simple wide surgical excision. PMID:7421377

  6. Live-cell luciferase assay of drug resistant cells

    OpenAIRE

    sprotocols

    2015-01-01

    To date, multiplexing cell-based assay is essential for high-throughput screening of molecular targets. Measuring multiple parameters of a single sample increases consistency and decrease time and cost of assay. Functional assay of living cell is useful as a first step of multiplexing assay, because live-cell assay allows following second assay using cell lysate or stained cell. However, live-cell assay of drug resistant cells that are highly activated of drug efflux mechanisms is sometimes u...

  7. [Dendritic cells and interaction with other cell types. Immune tolerance].

    Science.gov (United States)

    Guerder, S

    2001-07-01

    T cell tolerance to self antigen is mainly established in the thymus were self-reactive T cells are deleted. Interdigitating dendritic cells and medulary epithelial cells are directly involved in the deletion process. Some self-reactive T cells escape, however this thymic censorship and enter the peripheral pool of naive T cells. Multiple mechanisms are also at play in the periphery to control this potentially armfull T cells, this include deletion and immune deviation.

  8. A focus on parietal cells as a renewing cell population

    Institute of Scientific and Technical Information of China (English)

    Sherif; M; Karam

    2010-01-01

    The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3Hthymidine radioautography in combination with electron microscopy, it was possible to demonstrate that parietal cells belong to a continuously renewing epithelial cell lineage. In the gastric glands, stem cells anchored in the isthmus region are responsible for the production of parietal cells...

  9. Stem cells - biological update and cell therapy progress

    OpenAIRE

    GIRLOVANU, MIHAI; Susman, Sergiu; Soritau, Olga; RUS-CIUCA, DAN; MELINCOVICI, CARMEN; CONSTANTIN, ANNE-MARIE; Carmen Mihaela MIHU

    2015-01-01

    In recent years, the advances in stem cell research have suggested that the human body may have a higher plasticity than it was originally expected. Until now, four categories of stem cells were isolated and cultured in vivo: embryonic stem cells, fetal stem cells, adult stem cells and induced pluripotent stem cells (hiPSCs). Although multiple studies were published, several issues concerning the stem cells are still debated, such as: the molecular mechanisms of differentiation, the methods t...

  10. Liver epithelial cells inhibit proliferation and invasiveness of hepatoma cells.

    Science.gov (United States)

    Jeng, Kuo-Shyang; Jeng, Chi-Juei; Jeng, Wen-Juei; Sheen, I-Shyan; Li, Shih-Yun; Hung, Zih-Hang; Hsiau, Hsin-I; Yu, Ming-Che; Chang, Chiung-Fang

    2016-03-01

    Hepatocellular carcinoma (HCC) is a worldwide malignancy with poor prognosis. Liver progenitors or stem cells could be a potential therapy for HCC treatment since they migrate toward tumors. Rat liver epithelial (RLE) cells have both progenitor and stem cell-like properties. Therefore, our study elucidated the therapeutic effect of RLE cells in rat hepatoma cells. RLE cells were isolated from 10-day old rats and characterized for stem cell marker expression. RLE cells and rat hepatoma cells (H4-IIE-C3 cells) were co-cultured and divided into four groups with different ratios of RLE and hepatoma cells. Group A had only rat hepatoma cells as a control group. The ratios of rat hepatoma and RLE cells in group B, C and D were 5:1, 1:1 and 1:5, respectively. Effective inhibition of cell proliferation and migration was found in group D when compared to group A. There was a significant decrease in Bcl2 expression and increase in late apoptosis of rat hepatoma cells when adding more RLE cells. RLE cells reduced cell proliferation and migration of rat hepatoma cells. These results suggested that RLE cells could be used as a potential cell therapy. PMID:26647726

  11. Polarised cells, polarised views: Asymmetric cell division in hematopoietic cells.

    Directory of Open Access Journals (Sweden)

    Kim ePham

    2014-02-01

    Full Text Available It has long been recognised that alterations in cell shape and polarity play important roles in coordinating lymphocyte functions. In the last decade a new aspect of lymphocyte polarity, termed Asymmetric Cell Division (ACD, has attracted much attention. ACD has previously been shown to dictate or influence many aspects of development in model organisms such as the worm and the fly, and to be disrupted in disease. Recent observations that ACD also occurs in lymphocytes led to exciting speculations that ACD might influence lymphocyte differentiation and function, and leukaemia. However, dissecting the role that ACD might play in these activities is not straightforward, and the evidence to date for a functional role in lymphocyte fate determination has been controversial. In this review, we discuss the evidence to date for ACD in lymphocytes, and how it might influence lymphocyte fate. We also discuss current gaps in our knowledge, and suggest approaches to definitively test the physiological role of ACD in lymphocytes.

  12. Regulation of beta cell replication

    DEFF Research Database (Denmark)

    Lee, Ying C; Nielsen, Jens Høiriis

    2008-01-01

    Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

  13. Wnt-Dependent Control of Cell Polarity in Cultured Cells.

    Science.gov (United States)

    Runkle, Kristin B; Witze, Eric S

    2016-01-01

    The secreted ligand Wnt5a regulates cell polarity and polarized cell movement during development by signaling through the poorly defined noncanonical Wnt pathway. Cell polarity regulates most aspects of cell behavior including the organization of apical/basolateral membrane domains of epithelial cells, polarized cell divisions along a directional plane, and front rear polarity during cell migration. These characteristics of cell polarity allow coordinated cell movements required for tissue formation and organogenesis during embryonic development. Genetic model organisms have been used to identify multiple signaling pathways including Wnt5a that are required to establish cell polarity and regulate polarized cell behavior. However, the downstream signaling events that regulate these complex cellular processes are still poorly understood. The methods below describe assays to study Wnt5a-induced cell polarity in cultured cells, which may facilitate our understanding of these complex signaling pathways. PMID:27590152

  14. The new stem cell biology.

    OpenAIRE

    Quesenberry, Peter J.; Colvin, Gerald A; Lambert, Jean-Francois; Frimberger, Angela E.; Dooner, Mark S.; Mcauliffe, Christina I.; Miller, Caroline; Becker, Pamela; Badiavas, Evangelis; Falanga, Vincent J.; Elfenbein, Gerald; Lum, Lawrence G.

    2002-01-01

    Recent studies have indicated that bone marrow stem cells are capable of generating muscle, cardiac, hepatic, renal, and bone cells. Purified hematopoietic stem cells have generated cardiac and hepatic cells and reversed disease manifestations in these tissues. Hematopoietic stem cells also alter phenotype with cell cycle transit or circadian phase. During a cytokine stimulated cell cycle transit, reversible alterations of differentiation and engraftment occur. Primitive hematopoietic stem ce...

  15. Small cell glioblastoma or small cell carcinoma

    DEFF Research Database (Denmark)

    Hilbrandt, Christine; Sathyadas, Sathya; Dahlrot, Rikke H;

    2013-01-01

    was admitted to the hospital with left-sided loss of motor function. A MRI revealed a 6 cm tumor in the right temporoparietal area. The histology was consistent with both glioblastoma multiforme (GBM) and small cell lung carcinoma (SCLC) but IHC was suggestive of a SCLC metastasis. PET-CT revealed...

  16. Tracking Down Mutations Cell by Cell.

    Science.gov (United States)

    Kosik, Kenneth S

    2016-03-16

    Using somatic cell nuclear transfer, Hazen et al. (2016) examined clonally expanded single neurons for mutations and found ∼100 mutations from a variety of classes. Post-mitotic mutations in individual neurons represent an exploratory direction for finding fundamental origins of neurodegeneration. PMID:26985720

  17. Transition of mesenchymal stem/stromal cells to endothelial cells

    NARCIS (Netherlands)

    M. Crisan (Mihaela)

    2013-01-01

    textabstractMesenchymal stem/stromal cells (MSCs) are heterogeneous. A fraction of these cells constitute multipotent cells that can self-renew and mainly give rise to mesodermal lineage cells such as adipocytes, osteocytes and chondrocytes. The ability of MSCs to differentiate into endothelial cell

  18. Induction of embryonic stem cells to hematopoietic cells in vitro

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to get hematopoietic cells from embryonic stem (ES) cells and to study development mechanisms of hematopoietic cells, the method of inducing embryonic stem cells to hematopoietic cells was explored by differenciating mouse ES cells and human embryonic cells in three stages. The differentiated cells were identified by flow cytometry, immunohistochemistry and Wright's staining. The results showed that embryoid bodies (EBs) could form when ES cells were cultured in the medium with 2-mercaptoethanol (2-ME). However, cytokines, such as stem cell factor (SCF), thrombopoietin (TPO), interleukin-3 (IL-3), interleukin-6 (IL-6), erythropoietin (EPO) and granular colony stimulating factor (G-CSF), were not helpful for forming EBs. SCF, TPO and embryonic cell conditional medium were useful for the differentiation of mouse EBs to hematopoietic progenitors. Eighty-six percent of these cells were CD34+ after 6-d culture. Hematopoietic progenitors differentiated to B lymphocytes when they were cocultured with primary bone marrow stroma cells in the DMEM medium with SCF and IL-6. 14 d later, most of the cells were CD34-CD38+. Wright's staining and immunohistochemistry showed that 80% of these cells were plasma-like morphologically and immunoglubolin positive. The study of hematopoietic cells from human embryonic cells showed that human embryonic cell differentiation was very similar to that of mouse ES cells. They could form EBs in the first stage and the CD34 positive cells account for about 48.5% in the second stage.

  19. The cell biology of T-dependent B cell activation

    DEFF Research Database (Denmark)

    Owens, T; Zeine, R

    1989-01-01

    The requirement that CD4+ helper T cells recognize antigen in association with class II Major Histocompatibility Complex (MHC) encoded molecules constrains T cells to activation through intercellular interaction. The cell biology of the interactions between CD4+ T cells and antigen-presenting cells...

  20. Fuel cells: Operating flexibly

    Science.gov (United States)

    Lee, Young Moo

    2016-09-01

    Fuel cells typically function well only in rather limited temperature and humidity ranges. Now, a proton exchange membrane consisting of ion pair complexes is shown to enable improved fuel cell performance under a wide range of conditions that are unattainable with conventional approaches.

  1. The Constitution by Cell

    Science.gov (United States)

    Greenhut, Stephanie; Jones, Megan

    2010-01-01

    On their visit to the National Archives Experience in Washington, D.C., students in Jenni Ashley and Gay Brock's U.S. history classes at the Potomac School in McLean, Virginia, participated in a pilot program called "The Constitution by Cell." Armed with their cell phones, a basic understanding of the Constitution, and a willingness to participate…

  2. MICROBIAL FUEL CELL

    DEFF Research Database (Denmark)

    2008-01-01

    A novel microbial fuel cell construction for the generation of electrical energy. The microbial fuel cell comprises: (i) an anode electrode, (ii) a cathode chamber, said cathode chamber comprising an in let through which an influent enters the cathode chamber, an outlet through which an effluent...

  3. Cell Phones for Education

    Science.gov (United States)

    Roberson, James H.; Hagevik, Rita A.

    2008-01-01

    Cell phones are fast becoming an integral part of students' everyday lives. They are regarded as important companions and tools for personal expression. School-age children are integrating the cell phone as such, and thus placing a high value on them. Educators endeavor to instill in students a high value for education, but often meet with…

  4. Printed paper photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Huebler, Arved; Trnovec, Bystrik; Zillger, Tino; Ali, Moazzam; Wetzold, Nora [Inistitute for Print and Media Technology, Chemnitz University of Technology, Chemnitz (Germany); Mingebach, Markus; Wagenpfahl, Alexander; Deibel, Carsten [Experimental Physics VI, Julius-Maximilians-University of Wuerzburg (Germany); Dyakonov, Vladimir [Experimental Physics VI, Julius-Maximilians-University of Wuerzburg (Germany); Bavarian Center for Applied Energy Research e.V. (ZAE Bayern), Wuerzburg (Germany)

    2011-11-15

    Polymer/fullerene solar cells are printed on paper using a combination of gravure and flexographic printing techniques. The printed paper photovoltaic cells are free from expensive electrodes made with indium-tin oxide, silver, or gold. Oxidized zinc film is used as the electron-collecting layer. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Ghrelin and cell differentiation

    Institute of Scientific and Technical Information of China (English)

    Geyang Xu; Yin Li; Wenjiao An; Weizhen Zhang

    2008-01-01

    Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is a gastric hormone that has been found to have a wide variety of biological functions. This review summarizes our current understanding of the effects of ghrelin on cell differentiation and tissue development, with an emphasis on the lineage determination of mesenchymal stem cells.

  6. Mesangial cell biology

    Energy Technology Data Exchange (ETDEWEB)

    Abboud, Hanna E., E-mail: Abboud@uthscsa.edu

    2012-05-15

    Mesangial cells originate from the metanephric mesenchyme and maintain structural integrity of the glomerular microvascular bed and mesangial matrix homeostasis. In response to metabolic, immunologic or hemodynamic injury, these cells undergo apoptosis or acquire an activated phenotype and undergo hypertrophy, proliferation with excessive production of matrix proteins, growth factors, chemokines and cytokines. These soluble factors exert autocrine and paracrine effects on the cells or on other glomerular cells, respectively. MCs are primary targets of immune-mediated glomerular diseases such as IGA nephropathy or metabolic diseases such as diabetes. MCs may also respond to injury that primarily involves podocytes and endothelial cells or to structural and genetic abnormalities of the glomerular basement membrane. Signal transduction and oxidant stress pathways are activated in MCs and likely represent integrated input from multiple mediators. Such responses are convenient targets for therapeutic intervention. Studies in cultured MCs should be supplemented with in vivo studies as well as examination of freshly isolated cells from normal and diseases glomeruli. In addition to ex vivo morphologic studies in kidney cortex, cells should be studied in their natural environment, isolated glomeruli or even tissue slices. Identification of a specific marker of MCs should help genetic manipulation as well as selective therapeutic targeting of these cells. Identification of biological responses of MCs that are not mediated by the renin–angiotensin system should help development of novel and effective therapeutic strategies to treat diseases characterized by MC pathology.

  7. Stem cells in dermatology.

    Science.gov (United States)

    Ogliari, Karolyn Sassi; Marinowic, Daniel; Brum, Dario Eduardo; Loth, Fabrizio

    2014-01-01

    Preclinical and clinical research have shown that stem cell therapy could be a promising therapeutic option for many diseases in which current medical treatments do not achieve satisfying results or cure. This article describes stem cells sources and their therapeutic applications in dermatology today.

  8. T-cell costimulation

    DEFF Research Database (Denmark)

    Owens, T

    1996-01-01

    The CD40L molecule expressed by CD4+ regulatory T lymphocytes is known to deliver signals that activate B cells and macrophages. It now appears that CD40L regulates T cells themselves, during both their development and their participation in adaptive immune responses....

  9. Cell Maintenance Systems

    Science.gov (United States)

    Morrison, D. R.

    1985-01-01

    Living human cells require attachment to a suitable surface and special culture conditions in order to grow. These requirements are modified and amplified when cells are taken into a weightless environment. Special handling and maintenance systems are required for routine laboratory procedures conducted in the Orbiter and in the Spacelab. Methods were developed to maintain cells in special incubators designed for the Orbiter middeck, however, electrophoresis and other experiments require cells to be harvested off of the culture substrate before they can be processed or used. The cell transport assembly (CTA) was flown on STS-8, and results show that improvements are required to maintain adequate numbers of cells in this device longer than 48 hours. The life sciences middeck centrifuge probably can be used, but modifications will be required to transfer cells from the CTA and keep the cells sterile. Automated systems such as the Skylab SO-15 flight hardware and crew operated systems are being evaluated for use on the Space Shuttle, Spacelab, and Space Station research modules.

  10. Tumor cell metabolism

    Science.gov (United States)

    Romero-Garcia, Susana; Lopez-Gonzalez, Jose Sullivan; B´ez-Viveros, José Luis; Aguilar-Cazares, Dolores

    2011-01-01

    Cancer is a genetic disease that is caused by mutations in oncogenes, tumor suppressor genes and stability genes. The fact that the metabolism of tumor cells is altered has been known for many years. However, the mechanisms and consequences of metabolic reprogramming have just begun to be understood. In this review, an integral view of tumor cell metabolism is presented, showing how metabolic pathways are reprogrammed to satisfy tumor cell proliferation and survival requirements. In tumor cells, glycolysis is strongly enhanced to fulfill the high ATP demands of these cells; glucose carbons are the main building blocks in fatty acid and nucleotide biosynthesis. Glutaminolysis is also increased to satisfy NADPH regeneration, whereas glutamine carbons replenish the Krebs cycle, which produces metabolites that are constantly used for macromolecular biosynthesis. A characteristic feature of the tumor microenvironment is acidosis, which results from the local increase in lactic acid production by tumor cells. This phenomenon is attributed to the carbons from glutamine and glucose, which are also used for lactic acid production. Lactic acidosis also directs the metabolic reprogramming of tumor cells and serves as an additional selective pressure. Finally, we also discuss the role of mitochondria in supporting tumor cell metabolism. PMID:22057267

  11. Cell Proliferation in Neuroblastoma

    Directory of Open Access Journals (Sweden)

    Laura L. Stafman

    2016-01-01

    Full Text Available Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed.

  12. Patterning Stem Cell Differentiation

    OpenAIRE

    Vunjak-Novakovic, Gordana

    2008-01-01

    Regulation of cell differentiation and assembly remains a fundamental question in developmental biology. Now, a report from the Chen laboratory (Ruiz and Chen, 2008) describes an approach that represents a major step toward a more profound understanding of the geometric-force control of stem cell differentiation.

  13. Programmed cell death

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The purpose of this conference to provide a multidisciplinary forum for exchange of state-of-the-art information on the role programmed cell death plays in normal development and homeostasis of many organisms. This volume contains abstracts of papers in the following areas: invertebrate development; immunology/neurology; bcl-2 family; biochemistry; programmed cell death in viruses; oncogenesis; vertebrate development; and diseases.

  14. Solar cell concentrating system

    International Nuclear Information System (INIS)

    This study reviews fabrication techniques and testing facilities for different solar cells under concentration which have been developed and tested. It is also aimed to examine solar energy concentrators which are prospective candidates for photovoltaic concentrator systems. This may provide an impetus to the scientists working in the area of solar cell technology

  15. Electrochemical cell stack assembly

    Science.gov (United States)

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2010-06-22

    Multiple stacks of tubular electrochemical cells having a dense electrolyte disposed between an anode and a cathode preferably deposited as thin films arranged in parallel on stamped conductive interconnect sheets or ferrules. The stack allows one or more electrochemical cell to malfunction without disabling the entire stack. Stack efficiency is enhanced through simplified gas manifolding, gas recycling, reduced operating temperature and improved heat distribution.

  16. Modeling: driving fuel cells

    Directory of Open Access Journals (Sweden)

    Michael Francis

    2002-05-01

    Fuel cells were invented in 1839 by Sir William Grove, a Welsh judge and gentleman scientist, as a result of his experiments on the electrolysis of water. To put it simply, fuel cells are electrochemical devices that take hydrogen gas from fuel, combine it with oxygen from the air, and generate electricity and heat, with water as the only by-product.

  17. Dynamics of cell orientation

    Science.gov (United States)

    de, Rumi; Zemel, Assaf; Safran, Samuel A.

    2007-09-01

    Many physiological processes depend on the response of biological cells to mechanical forces generated by the contractile activity of the cell or by external stresses. Using a simple theoretical model that includes the forces due to both the mechanosensitivity of cells and the elasticity of the matrix, we predict the dynamics and orientation of cells in both the absence and presence of applied stresses. The model predicts many features observed in measurements of cellular forces and orientation including the increase with time of the cellular forces in the absence of applied stress and the consequent decrease of the force in the presence of quasi-static stresses. We also explain the puzzling observation of parallel alignment of cells for static and quasi-static stresses and of nearly perpendicular alignment for dynamically varying stresses. In addition, we predict the response of the cellular orientation to a sinusoidally varying applied stress as a function of frequency.

  18. Physics of adherent cells

    Science.gov (United States)

    Schwarz, Ulrich S.; Safran, Samuel A.

    2013-07-01

    One of the most unique physical features of cell adhesion to external surfaces is the active generation of mechanical force at the cell-material interface. This includes pulling forces generated by contractile polymer bundles and networks, and pushing forces generated by the polymerization of polymer networks. These forces are transmitted to the substrate mainly by focal adhesions, which are large, yet highly dynamic adhesion clusters. Tissue cells use these forces to sense the physical properties of their environment and to communicate with each other. The effect of forces is intricately linked to the material properties of cells and their physical environment. Here a review is given of recent progress in our understanding of the role of forces in cell adhesion from the viewpoint of theoretical soft matter physics and in close relation to the relevant experiments.

  19. Fifty cell test facility

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, J. D.; Kolba, V. M.; Miller, W. E.; Gay, E. C.

    1980-07-01

    This report describes the design of a facility capable of the simultaneous testing of up to 50 high-temperature (400 to 500/sup 0/C) lithium alloy/iron sulfide cells; this facility is located in the Chemical Engineering Division of Argonne National Laboratory (ANL). The emphasis will be on the lifetime testing of cells fabricated by ANL and industrial contractors to acquire statistical data on the performance of cells of various designs. A computer-based data-acquisition system processes the cell performance data generated from the cells on test. The terminals and part of the data-acquisition equipment are housed in an air-conditioned enclosure adjacent to the testing facility; the computer is located remotely.

  20. Cell Control Engineering

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo

    1996-01-01

    The engineering process of creating cell control systems is described, and a Cell Control Engineering (CCE) concept is defined. The purpose is to assist people, representing different disciplines in the organisation, to implement cell controllers by addressing the complexity of having many systems...... in physically and logically different and changing manufacturing environments. The defined CCE concept combines state-of-the-art of commercially available enabling technologies for automation system software development, generic cell control models and guidelines for the complete engineering process....... It facilitates the understanding of the task and structure of cell controllers and uses this knowledge directly in the implementation of the system. By applying generic models CCE facilitates reuse of software components and maintenance of applications. In many enterprises, software makes up an increasing part...

  1. Cell fusions in mammals

    DEFF Research Database (Denmark)

    Larsson, Lars-Inge; Bjerregaard, Bolette; Talts, Jan Fredrik

    2008-01-01

    Cell fusions are important to fertilization, placentation, development of skeletal muscle and bone, calcium homeostasis and the immune defense system. Additionally, cell fusions participate in tissue repair and may be important to cancer development and progression. A large number of factors appear...... to regulate cell fusions, including receptors and ligands, membrane domain organizing proteins, proteases, signaling molecules and fusogenic proteins forming alpha-helical bundles that bring membranes close together. The syncytin family of proteins represent true fusogens and the founding member, syncytin-1......, has been documented to be involved in fusions between placental trophoblasts, between cancer cells and between cancer cells and host ells. We review the literature with emphasis on the syncytin family and propose that syncytins may represent universal fusogens in primates and rodents, which work...

  2. Metallization of bacteria cells

    Institute of Scientific and Technical Information of China (English)

    LI; Xiangfeng; (黎向锋); LI; Yaqin; (李雅芹); CAI; Jun; (蔡军); ZHANG; Deyuan; (张德远)

    2003-01-01

    Bacteria cells with different standard shapes are well suited for use as templates for the fabrication of magnetic and electrically conductive microstructures. In this paper, metallization of bacteria cells is demonstrated by an electroless deposition technique of nickel-phosphorus initiated by colloid palladium-tin catalyst on the surfaces of Citeromyces matritensis and Bacillus cereus. The activated and metallized bacteria cells have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD). Results showed that both Citeromyces matritensis and Bacillus cereus had no deformation in shape after metallization; the metallized films deposited on the surfaces of bacteria cells are homogeneous in thickness and noncrystalline in phase structure. The kinetics of colloid palladium-tin solution and electroless plating on bacteria cells is discussed.

  3. Solid electrolytic fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Masayasu; Yamauchi, Yasuhiro; Kamisaka, Mitsuo; Notomi, Kei.

    1989-04-21

    Concerning a solid electrolytic fuel cell with a gas permeable substrate pipe, a fuel electrode installed on this substrate pipe and an air electrode which is laminated on this fuel electrode with the electrolyte in between, the existing fuel cell of this kind uses crystals of CaMnO3, etc. for the material of the air electrode, but its electric resistance is big and in order to avert this, it is necessary to make the film thickness of the air electrode big. However, in such a case, the entry of the air into its inside worsens and the cell performance cannot develop satisfactorily. In view of the above, in order to obtain a high performance solid electrolytic fuel cell which can improve electric conductivity without damaging diffusion rate of the air, this invention proposes with regard to the aforementioned solid electrolytic fuel cell to install a heat resistant and conductive member inside the above air electrode. 6 figs.

  4. Nanoelectrochemistry of mammalian cells.

    Science.gov (United States)

    Sun, Peng; Laforge, François O; Abeyweera, Thushara P; Rotenberg, Susan A; Carpino, James; Mirkin, Michael V

    2008-01-15

    There is a significant current interest in development of new techniques for direct characterization of the intracellular redox state and high-resolution imaging of living cells. We used nanometer-sized amperometric probes in combination with the scanning electrochemical microscope (SECM) to carry out spatially resolved electrochemical experiments in cultured human breast cells. With the tip radius approximately 1,000 times smaller than that of a cell, an electrochemical probe can penetrate a cell and travel inside it without apparent damage to the membrane. The data demonstrate the possibility of measuring the rate of transmembrane charge transport and membrane potential and probing redox properties at the subcellular level. The same experimental setup was used for nanoscale electrochemical imaging of the cell surface. PMID:18178616

  5. Digital Microfluidic Cell Culture.

    Science.gov (United States)

    Ng, Alphonsus H C; Li, Bingyu Betty; Chamberlain, M Dean; Wheeler, Aaron R

    2015-01-01

    Digital microfluidics (DMF) is a droplet-based liquid-handling technology that has recently become popular for cell culture and analysis. In DMF, picoliter- to microliter-sized droplets are manipulated on a planar surface using electric fields, thus enabling software-reconfigurable operations on individual droplets, such as move, merge, split, and dispense from reservoirs. Using this technique, multistep cell-based processes can be carried out using simple and compact instrumentation, making DMF an attractive platform for eventual integration into routine biology workflows. In this review, we summarize the state-of-the-art in DMF cell culture, and describe design considerations, types of DMF cell culture, and cell-based applications of DMF. PMID:26643019

  6. Photovoltaic solar cell

    Science.gov (United States)

    Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

    2015-09-08

    A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

  7. PEM regenerative fuel cells

    Science.gov (United States)

    Swette, Larry L.; Laconti, Anthony B.; McCatty, Stephen A.

    1993-11-01

    This paper will update the progress in developing electrocatalyst systems and electrode structures primarily for the positive electrode of single-unit solid polymer proton exchange membrane (PEM) regenerative fuel cells. The work was done with DuPont Nafion 117 in complete fuel cells (40 sq cm electrodes). The cells were operated alternately in fuel cell mode and electrolysis mode at 80 C. In fuel cell mode, humidified hydrogen and oxygen were supplied at 207 kPa (30 psi); in electrolysis mode, water was pumped over the positive electrode and the gases were evolved at ambient pressure. Cycling data will be presented for Pt-Ir catalysts and limited bifunctional data will be presented for Pt, Ir, Ru, Rh, and Na(x)Pt3O4 catalysts as well as for electrode structure variations.

  8. Solar cell radiation handbook

    Science.gov (United States)

    Tada, H. Y.; Carter, J. R., Jr.; Anspaugh, B. E.; Downing, R. G.

    1982-01-01

    The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  9. Advances in stem cell research

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@In 1998, biologists Thomson and Gearhart successfully derived stem cells from human embryos. One year later, several researchers discovered that adult stem cells still retain the ability to be differentiated into unrelated types of cells. Advances in stem cell research open a promising direction for applied medical science. Moreover, it may also force scientists to reconsider the fundamental theory about how cells grow up. Stem cell research was considered by Science as the top of the ten breakthroughs of science of the year[1]. This paper gives a survey of recent advances in stem cell research. 1 Overview In the 1980s, embryonic stem cell and/or embryonic germ cell line (ES cell line, EG cell line) of multifarious mammalian animals, especially those of non-human pri-mates, had been established. In 1998, Thomson and Shamblott obtained ES, EG cell lines from human blasto-cysts and gonad ridges of early human embryos, respec-tively. Their research brought up an ethical debate about whether human embryos can be used as experimental materials. It was not appeased until 1999 when research-ers discovered that stem cells from adults still retain the ability to become different kinds of tissue cells. For in-stance, brain cells can become blood cells[2], and cells from bone marrow can become cells in liver. Scientists believe, for a long time, that cells can only be developed from early pluripotent embryo cells; the differentiation potential of stem cells from mature tissues is restricted to only one of the cell types of the tissue where stem cells are obtained. Recent stem cell researches, however, sub-verted the traditional view of stem cells. These discoveries made scientists speed ahead with the work on adult stem cells, hoping to discover whether their promise will rival that of ES cells.

  10. [Merkel cell skin carcinoma].

    Science.gov (United States)

    Krejcí, K; Zadrazil, J; Tichý, T; Horák, P; Ciferská, H; Hodulová, M; Zezulová, M; Zlevorová, M

    2010-01-01

    Merkel cell carcinoma is a rare tumour of the skin. It affects predominantly elderly Caucasian males on sun-exposed areas of the skin. Distinctively more frequent and at significantly lower age, its incidence is higher in immunocompromised patients. In these patients we often observe the highly aggressive course of Merkel cell carcinoma and a fatal outcome. The incidence of Merkel cell carcinoma has been rising in recent years and is more dramatic than the increased incidence of cutaneous melanoma. More than one-third of Merkel cell carcinoma patients will die from this cancer, making it twice as lethal as melanoma. The malignant transformation of Merkel cells is currently thought to be related to an infection with Merkel cell polyomavirus. In the early stage the discreet clinical picture may be contrary to extensive microscopic invasion and this seemingly benign appearance can delay diagnosis or increase the risk of insufficient tumour excision. The diagnosis is definitely confirmed by histological evaluation and immunohistochemical tests. A typical feature is the tendency of Merkel cell carcinoma to frequent local recurrence and early metastasizing into regional lymph nodes with subsequent tumour generalization. The mainstay of therapy is radical excision of the tumour and adjuvant radiotherapy targeted at the site of primary incidence and local draining lymph nodes. The efficacy of different chemotherapy protocols in Merkel cell carcinoma is limited and the median survival rate is measured in months. In the future, prophylaxis with vaccination against Merkel cell polyomavirus will hopefully be possible in high-risk patients, as well as therapeutic usage of antisense oligonucleotides or microRNAs, eventually complete Merkel cell carcinoma elimination by affecting the tumour suppressor gene Atonal homolog 1 expression. The staging of the tumour at time of diagnosis is the most important prognostic factor. In this respect, the importance of preventative skin

  11. Langerhans' cells, veiled cells, and interdigitating cells in the mouse recognized by a monoclonal antibody

    OpenAIRE

    1986-01-01

    An mAb, NLDC-145, is described that specifically reacts with a group of nonlymphoid dendritic cells including Langerhans cells (LC), veiled cells (VC), and interdigitating cells (IDC). The antibody does not react with precursor cells in bone marrow and blood. Macrophages are not stained by the antibody, but a subpopulation of Ia+ peritoneal exudate cells is recognized. Possible relationships of the various nonlymphoid dendritic cell (NLDC) types are discussed.

  12. From Adult Bone Marrow Cells to Other Cell Lineages:Transdifferentiation or Cells Fusion

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Recent studies have demonstrated that intravenous transplantation or local injection of bone marrow cells can induce unexpected changes of their fate. The results of these experiments showed that after transplantation or injecton, some of tissue specific somatic cells such as hepatocytes, skeleton, cardiac muscle cells and brain cells expressed the donor cell-specific genes, such as Y chromosome. There are two hypotheses that can explain this phenomenon. One is bone marrow stem cell transdifferentiation and the other is spontaneous cell fusion.

  13. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    OpenAIRE

    Stefania Bruno; Cristina Grange; Marta Tapparo; Chiara Pasquino; Renato Romagnoli; Ennia Dametto; Antonio Amoroso; Ciro Tetta; Giovanni Camussi

    2016-01-01

    Human liver stem cells (HLSCs) are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs), and dendritic cells (DCs) in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell co...

  14. Diffusion inside living human cells

    DEFF Research Database (Denmark)

    Leijnse, N.; Jeon, J. -H.; Loft, Steffen;

    2012-01-01

    cells. For these cells the exact diffusional pattern of a particular granule depends on the physiological state of the cell and on the localization of the granule within the cytoplasm. Granules located close to the actin rich periphery of the cell move less than those located towards to the center...... of the cell or within the nucleus. Also, granules in cells which are stressed by intense laser illumination or which have attached to a surface for a long period of time move in a more restricted fashion than those within healthy cells. For granules diffusing in healthy cells, in regions away from the cell...

  15. Many facets of stem cells

    Institute of Scientific and Technical Information of China (English)

    Jiarui Wu

    2011-01-01

    @@ Research area on stem cells is one of frontiers in biology.The collection of five research articles in this issue aims to cover timely developments in stem cell biology, ranging from generating and identifying stem cell line to manipulating stem cells, and from basic mechanism analysis to applied medical potential.These papers reflect the various research tasks in stem cell biology.

  16. Microfluidics for single cell analysis

    DEFF Research Database (Denmark)

    Jensen, Marie Pødenphant

    Isolation and manipulation of single cells have gained an increasing interest from researchers because of the heterogeneity of cells from the same cell culture. Single cell analysis can ensure a better understanding of differences between individual cells and potentially solve a variety of clinic...

  17. Oscillating Cell Culture Bioreactor

    Science.gov (United States)

    Freed, Lisa E.; Cheng, Mingyu; Moretti, Matteo G.

    2010-01-01

    To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid

  18. Mesenchymal stem cells: cell biology and potential use in therapy

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Kristiansen, Malthe; Abdallah, Basem M

    2004-01-01

    Mesenchymal stem cells are clonogenic, non-haematopoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages e.g. osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages e.g. neuronal-like cells. Several methods...... are currently available for isolation of the mesenchymal stem cells based on their physical and immunological characteristics. Because of the ease of their isolation and their extensive differentiation potential, mesenchymal stem cells are among the first stem cell types to be introduced in the clinic. Recent...... studies have demonstrated that the life span of mesenchymal stem cells in vitro can be extended by increasing the levels of telomerase expression in the cells and thus allowing culture of large number of cells needed for therapy. In addition, it has been shown that it is possible to culture the cells...

  19. Immunology of Stem Cells and Cancer Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Yang

    2007-01-01

    The capacity of pluri-potent stem cells to repair the tissues in which stem cells reside holds great promise in development of novel cell replacement therapeutics for treating chronic and degenerative diseases. However,numerous reports show that stem cell therapy, even in an autologous setting, triggers lymphocyte infiltration and inflammation. Therefore, an important question to be answered is how the host immune system responds to engrafted autologous stem cells or allogeneous stem cells. In this brief review, we summarize the progress in several related areas in this field, including some of our data, in four sections: (1) immunogenicity of stem cells; (2)strategies to inhibit immune rejection to allograft stem cells; (3) immune responses to cancer stem cells; and (4)mesenchymal stem cells in immune regulation. Improvement of our understanding on these and other aspects of immune system-stem cell interplay would greatly facilitate the development of stem cell-based therapeutics for regenerative purposes.

  20. Dedifferentiation of committed epithelial cells into stem cells in vivo

    OpenAIRE

    Tata, Purushothama Rao; Mou, Hongmei; Pardo-Saganta, Ana; Zhao, Rui; Prabhu, Mythili; Law, Brandon M.; Vinarsky, Vladimir; Josalyn L Cho; Breton, Sylvie; Sahay, Amar; Medoff, Benjamin D.; Rajagopal, Jayaraj

    2013-01-01

    Summary Cellular plasticity contributes to the regenerative capacity of plants, invertebrates, teleost fishes, and amphibians. In vertebrates, differentiated cells are known to revert into replicating progenitors, but these cells do not persist as stable stem cells. We now present evidence that differentiated airway epithelial cells can revert into stable and functional stem cells in vivo. Following the ablation of airway stem cells, we observed a surprising increase in the proliferation of c...

  1. Dedifferentiation of committed epithelial cells into stem cells in vivo

    OpenAIRE

    Tata, Purushothama Rao; Mou, Hongmei; Pardo-Saganta, Ana; Zhao, Rui; Prabhu, Mythili; Law, Brandon M.; Vinarsky, Vladimir; Josalyn L Cho; Breton, Sylvie; Sahay, Amar; Medoff, Benjamin D.; Rajagopal, Jayaraj

    2014-01-01

    Summary Cellular plasticity contributes to the regenerative capacity of plants, invertebrates, teleost fishes, and amphibians. In vertebrates, differentiated cells are known to revert into replicating progenitors, but these cells do not persist as stable stem cells. We now present evidence that differentiated airway epithelial cells can revert into stable and functional stem cells in vivo. Following the ablation of airway stem cells, we observed a surprising increase in the proliferation of c...

  2. Defective alloantigen-presenting capacity of 'Langerhans cell histiocytosis cells'.

    OpenAIRE

    Yu, R C; Morris, J F; Pritchard, J.; Chu, T C

    1992-01-01

    The functional activity of skin cells derived from an infant who died of multisystem Langerhans cell histiocytosis (LCH) was examined. Involved and non-involved skin was obtained at postmortem examination within three hours of death; normal epidermal Langerhans cells and 'LCH cells' were separated by means of dispase digestion. The functional activity of different populations of CD1a positive cells was assessed using the conventional six day allogeneic mixed cell reaction. Compared with Lange...

  3. Differentiation of human embryonic stem cells into insulin- secreting cells

    OpenAIRE

    S Mollamohammadi; Massumi, M.; H Jafary; Baharvand, H.

    2006-01-01

    Introduction: Type I diabetes mellitus is caused by autoimmune destruction of the insulin-producing β-cells. A new potential method for curing the disease is transplantation of differentiated insulin- secreting cells from human embryonic stem cells. Methods: Human embryonic stem cell lines (Royan H1) were used to produce embryoid bodies. Differentiation carried out by growth factor-mediated selection of nestin positive cells. In final stage, these cells were expanded in the presence of bFGF, ...

  4. The Cell Surface Proteome of Human Mesenchymal Stromal Cells

    OpenAIRE

    Christian Niehage; Charlotte Steenblock; Theresia Pursche; Martin Bornhäuser; Denis Corbeil; Bernard Hoflack

    2011-01-01

    BACKGROUND: Multipotent human mesenchymal stromal cells (hMSCs) are considered as promising biological tools for regenerative medicine. Their antibody-based isolation relies on the identification of reliable cell surface markers. METHODOLOGY/PRINCIPAL FINDINGS: To obtain a comprehensive view of the cell surface proteome of bone marrow-derived hMSCs, we have developed an analytical pipeline relying on cell surface biotinylation of intact cells using cell impermeable, cleavable sulfo-NHS-SS-bio...

  5. A novel cell subset:Interferon-producing killer dendritic cells

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Recent reports introduce a novel cell subset of DCs with antigenic phenotypes shared by both NK cells and B cells, but without surface markers of pDCs and T cells, appearing to be a chimera of NK cells and DCs, namely interferon-producing killer dendritic cells(IKDCs).IKDCs not only secret type I and type II interferons to recognize and kill tumor cells effectively, but also express MHC-II molecules to present antigens.Thus, IKDCs are considered as important immunosurveilance cells for tumors, providing a link between innate and adaptive immunity.

  6. Embryonic stem cells: prospects for developmental biology and cell therapy.

    Science.gov (United States)

    Wobus, Anna M; Boheler, Kenneth R

    2005-04-01

    Stem cells represent natural units of embryonic development and tissue regeneration. Embryonic stem (ES) cells, in particular, possess a nearly unlimited self-renewal capacity and developmental potential to differentiate into virtually any cell type of an organism. Mouse ES cells, which are established as permanent cell lines from early embryos, can be regarded as a versatile biological system that has led to major advances in cell and developmental biology. Human ES cell lines, which have recently been derived, may additionally serve as an unlimited source of cells for regenerative medicine. Before therapeutic applications can be realized, important problems must be resolved. Ethical issues surround the derivation of human ES cells from in vitro fertilized blastocysts. Current techniques for directed differentiation into somatic cell populations remain inefficient and yield heterogeneous cell populations. Transplanted ES cell progeny may not function normally in organs, might retain tumorigenic potential, and could be rejected immunologically. The number of human ES cell lines available for research may also be insufficient to adequately determine their therapeutic potential. Recent molecular and cellular advances with mouse ES cells, however, portend the successful use of these cells in therapeutics. This review therefore focuses both on mouse and human ES cells with respect to in vitro propagation and differentiation as well as their use in basic cell and developmental biology and toxicology and presents prospects for human ES cells in tissue regeneration and transplantation.

  7. A novel cell subset: Interferon-producing killer dendritic cells

    Institute of Scientific and Technical Information of China (English)

    WANG JiongKun; XING FeiYue

    2008-01-01

    Recent reports introduce a novel cell subset of DCs with antigenic phenotypes shared by both NK cells and B cells, but without surface markers of pDCs and T cells, appearing to be a chimera of NK cells and DCs, namely interferon-producing killer dendritic cells (IKDCs). IKDCs not only secret type Ⅰ and type Ⅱ interferons to recognize and kill tumor cells effectively, but also express MHC-Ⅱ molecules to present antigens. Thus, IKDCs are considered as important immunosurveilance cells for tumors, providing a link between innate and adaptive immunity.

  8. Quantum dot solar cells

    CERN Document Server

    Wu, Jiang

    2013-01-01

    The third generation of solar cells includes those based on semiconductor quantum dots. This sophisticated technology applies nanotechnology and quantum mechanics theory to enhance the performance of ordinary solar cells. Although a practical application of quantum dot solar cells has yet to be achieved, a large number of theoretical calculations and experimental studies have confirmed the potential for meeting the requirement for ultra-high conversion efficiency. In this book, high-profile scientists have contributed tutorial chapters that outline the methods used in and the results of variou

  9. Stem Cells and Cancer

    International Nuclear Information System (INIS)

    Stem cell research has thrived over the last years due to their therapeutic and regenerative potential. Scientific breakthroughs in the field are immediately translated from the scientific journals to the mass media, which is not surprising as the characterisation of the molecular mechanisms that regulate the biology of stem cells is crucial for the treatment of degenerative and cardiovascular diseases, as well as cancer. In the Molecular Oncology Unit at Ciemat we work to unravel the role of cancer stem cells in tumour development, and to find new antitumor therapies. (Author)

  10. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available Dye sensitized solar cell (DSSC is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  11. Limbal Stem Cell Therapy

    OpenAIRE

    Kringlegarden, Hilde Grane

    2013-01-01

    It is widely accepted today that stem cells in the adult corneal epithelium is located to the limbus. No specific marker of limbal epithelial cells (LESCs) has been identified, yet many have been suggested, including ΔNp63α, ABCG2, vimentin and notch 1. Negative markers include amongst others the differentiation markers Ck3 and Ck12. The lack of an identified specific marker elucidates the need for establishment of more exact molecular markers of LESCs. Limbal stem cell deficiency (LSCD) may ...

  12. Congenital granular cell epulis.

    Science.gov (United States)

    Conrad, Rachel; Perez, Mia C N

    2014-01-01

    Congenital granular cell epulis is a rarely reported lesion of unknown histogenesis with a strong predilection for the maxillary alveolar ridge of newborn girls. Microscopically, it demonstrates nests of polygonal cells with granular cytoplasm, a prominent capillary network, and attenuated overlying squamous epithelium. The lesion lacks immunoreactivity for S-100, laminin, chromogranin, and most other markers except neuron-specific enolase and vimentin. Through careful observation of its unique clinical, histopathologic, and immunohistochemical features, this lesion can be distinguished from the more common adult granular cell tumor as well as other differential diagnoses.

  13. Materials for fuel cells

    Directory of Open Access Journals (Sweden)

    Sossina M Haile

    2003-03-01

    Full Text Available Because of their potential to reduce the environmental impact and geopolitical consequences of the use of fossil fuels, fuel cells have emerged as tantalizing alternatives to combustion engines. Like a combustion engine, a fuel cell uses some sort of chemical fuel as its energy source but, like a battery, the chemical energy is directly converted to electrical energy, without an often messy and relatively inefficient combustion step. In addition to high efficiency and low emissions, fuel cells are attractive for their modular and distributed nature, and zero noise pollution. They will also play an essential role in any future hydrogen fuel economy.

  14. PLUTONIUM ELECTROREFINING CELLS

    Science.gov (United States)

    Mullins, L.J. Jr.; Leary, J.A.; Bjorklund, C.W.; Maraman, W.J.

    1963-07-16

    Electrorefining cells for obtaining 99.98% plutonium are described. The cells consist of an impure liquid plutonium anode, a molten PuCl/sub 3/-- alkali or alkaline earth metal chloanode, a molten PuCl/sub 3/-alkali or alkaline earth metal chloride electrolyte, and a nonreactive cathode, all being contained in nonreactive ceramic containers which separate anode from cathode by a short distance and define a gap for the collection of the purified liquid plutonium deposited on the cathode. Important features of these cells are the addition of stirrer blades on the anode lead and a large cathode surface to insure a low current density. (AEC)

  15. Stem cells and transplant arteriosclerosis.

    Science.gov (United States)

    Xu, Qingbo

    2008-05-01

    Stem cells can differentiate into a variety of cells to replace dead cells or to repair damaged tissues. Recent evidence indicates that stem cells are involved in the pathogenesis of transplant arteriosclerosis, an alloimmune initiated vascular stenosis that often results in transplant organ failure. Although the pathogenesis of transplant arteriosclerosis is not yet fully understood, recent developments in stem cell research have suggested novel mechanisms of vascular remodeling in allografts. For example, stem cells derived from the recipient may repair damaged endothelial cells of arteries in transplant organs. Further evidence suggests that stem cells or endothelial progenitor cells may be released from both bone marrow and non-bone marrow tissues. Vascular stem cells appear to replenish cells that died in donor vessels. Concomitantly, stem/progenitor cells may also accumulate in the intima, where they differentiate into smooth muscle cells. However, several issues concerning the contribution of stem cells to the pathogenesis of transplant arteriosclerosis are controversial, eg, whether bone marrow-derived stem cells can differentiate into smooth muscle cells that form neointimal lesions of the vessel wall. This review summarizes recent research on the role of stem cells in transplant arteriosclerosis, discusses the mechanisms of stem cell homing and differentiation into mature endothelial and smooth muscle cells, and highlights the controversial issues in the field.

  16. Primitive human hematopoietic cells give rise to differentially specified daughter cells upon their initial cell division.

    NARCIS (Netherlands)

    Giebel, B.; Zhang, T.; Beckmann, J.; Spanholtz, J.; Wernet, P.; Ho, A.; Punzel, M.

    2006-01-01

    It is often predicted that stem cells divide asymmetrically, creating a daughter cell that maintains the stem-cell capacity, and 1 daughter cell committed to differentiation. While asymmetric stem-cell divisions have been proven to occur in model organisms (eg, in Drosophila), it remains illusive wh

  17. CD81 is dispensable for hepatitis C virus cell-to-cell transmission in hepatoma cells.

    Science.gov (United States)

    Witteveldt, Jeroen; Evans, Matthew J; Bitzegeio, Julia; Koutsoudakis, George; Owsianka, Ania M; Angus, Allan G N; Keck, Zhen-Yong; Foung, Steven K H; Pietschmann, Thomas; Rice, Charles M; Patel, Arvind H

    2009-01-01

    Hepatitis C virus (HCV) infects cells by the direct uptake of cell-free virus following virus engagement with specific cell receptors such as CD81. Recent data have shown that HCV is also capable of direct cell-to-cell transmission, although the role of CD81 in this process is disputed. Here, we generated cell culture infectious strain JFH1 HCV (HCVcc) genomes carrying an alanine substitution of E2 residues W529 or D535 that are critical for binding to CD81 and infectivity. Co-cultivation of these cells with naïve cells expressing enhanced green fluorescent protein (EGFP) resulted in a small number of cells co-expressing both EGFP and HCV NS5A, showing that the HCVcc mutants are capable of cell-to-cell spread. In contrast, no cell-to-cell transmission from JFH1(DeltaE1E2)-transfected cells occurred, indicating that the HCV glycoproteins are essential for this process. The frequency of cell-to-cell transmission of JFH1(W529A) was unaffected by the presence of neutralizing antibodies that inhibit E2-CD81 interactions. By using cell lines that expressed little or no CD81 and that were refractive to infection with cell-free virus, we showed that the occurrence of viral cell-to-cell transmission is not influenced by the levels of CD81 on either donor or recipient cells. Thus, our results show that CD81 plays no role in the cell-to-cell spread of HCVcc and that this mode of transmission is shielded from neutralizing antibodies. These data suggest that therapeutic interventions targeting the entry of cell-free HCV may not be sufficient in controlling an ongoing chronic infection, but need to be complemented by additional strategies aimed at disrupting direct cell-to-cell viral transmission. PMID:19088272

  18. Fuel cells: Problems and prospects

    OpenAIRE

    Shukla, AK; Ramesh, KV; Kannan, AM

    1986-01-01

    n recent years, fuel cell technology has advanced significantly. Field trials on certain types of fuel cells have shown promise for electrical use. This article reviews the electrochemistry, problems and prospects of fuel cell systems.

  19. Stem Cell Transplants (For Teens)

    Science.gov (United States)

    ... Can I Help a Friend Who Cuts? Stem Cell Transplants KidsHealth > For Teens > Stem Cell Transplants Print ... it Take to Recover? Coping What Are Stem Cells? As you probably remember from biology class, every ...

  20. Kinetics of adrenal medullary cells.

    OpenAIRE

    Verhofstad, A A

    1993-01-01

    The adrenal medulla of mammals has a heterogeneous population of cells. In adults most are epithelial cells containing a particular type of cytoplasmic granule. Based on a variety of cytochemical and ultrastructural studies it is now accepted that 2 different adrenal medullary chromaffin cell types can be distinguished, i.e. noradrenaline (NA) and adrenaline (A) synthesising and storing cells. Other cell types present in the adrenal medulla include neuronal elements comprising either cell bod...

  1. Rejuvenation of automotive fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Seung; Langlois, David A.

    2016-08-23

    A process for rejuvenating fuel cells has been demonstrated to improve the performance of polymer exchange membrane fuel cells with platinum/ionomer electrodes. The process involves dehydrating a fuel cell and exposing at least the cathode of the fuel cell to dry gas (nitrogen, for example) at a temperature higher than the operating temperature of the fuel cell. The process may be used to prolong the operating lifetime of an automotive fuel cell.

  2. Pancreatic Stem Cells Remain Unresolved

    OpenAIRE

    Jiang, Fang-Xu; Morahan, Grant

    2014-01-01

    Diabetes mellitus is caused by absolute (type 1) or relative (type 2) deficiency of insulin-secreting islet β cells. An ideal treatment of diabetes would, therefore, be to replace the lost or deficient β cells, by transplantation of donated islets or differentiated endocrine cells or by regeneration of endogenous islet cells. Due to their ability of unlimited proliferation and differentiation into all functional lineages in our body, including β cells, embryonic stem cells and induced pluripo...

  3. Mast cells in bacterial infections

    OpenAIRE

    Rönnberg, Elin

    2014-01-01

    Mast cells are implicated in immunity towards bacterial infection, but the molecular mechanisms by which mast cells contribute to the host response are only partially understood. Previous studies have examined how mast cells react to purified bacterial cell wall components, such as peptidoglycan and lipopolysaccharide. To investigate how mast cells react to live bacteria we co-cultured mast cells and the gram-positive bacteria Streptococcus equi (S. equi) and Staphylococcus aureus (S. aureus)...

  4. FUEL CELLS IN ENERGY PRODUCTION

    OpenAIRE

    Huang, Xiaoyu

    2011-01-01

    The purpose of this thesis is to study fuel cells. They convert chemical energy directly into electrical energy with high efficiency and low emmission of pollutants. This thesis provides an overview of fuel cell technology.The basic working principle of fuel cells and the basic fuel cell system components are introduced in this thesis. The properties, advantages, disadvantages and applications of six different kinds of fuel cells are introduced. Then the efficiency of each fuel cell is p...

  5. Concise Review: Asymmetric Cell Divisions in Stem Cell Biology

    Directory of Open Access Journals (Sweden)

    Florian Murke

    2015-11-01

    Full Text Available Somatic stem cells are rare cells with unique properties residing in many organs and tissues. They are undifferentiated cells responsible for tissue regeneration and homeostasis, and contain both the capacity to self-renew in order to maintain their stem cell potential and to differentiate towards tissue-specific, specialized cells. However, the knowledge about the mechanisms controlling somatic stem cell fate decisions remains sparse. One mechanism which has been described to control daughter cell fates in selected somatic stem cell systems is the process of asymmetric cell division (ACD. ACD is a tightly regulated and evolutionary conserved process allowing a single stem or progenitor cell to produce two differently specified daughter cells. In this concise review, we will summarize and discuss current concepts about the process of ACD as well as different ACD modes. Finally, we will recapitulate the current knowledge and our recent findings about ACD in human hematopoiesis.

  6. Dazl Promotes Germ Cell Differentiation from Embryonic Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Zhuo Yu; Ping Ji; Jinping Cao; Shu Zhu; Yao Li; Lin Zheng; Xuejin Chen; Lixin Feng

    2009-01-01

    It has been demonstrated that through the formation of embryoid bodies (Ebs) germ cells can be derived from embryonic stem (ES) cells. Here, we describe a transgene expression approach to derive germ cells directly from ES cells in vitro without EB formation. Through the ectopic expression of Deleted in Azoospermia-Like (Dazl), a germ cell-specific RNA-binding protein,both motile tailed-sperm and oocytes were induced from mouse ES (mES) cells in culture. Furthermore, transient overexpression of Dazl led to suppression of Nanog but induced germ cell nuclear antigen in mES cells. Dazl knockdown resulted in reduction in the expression of germ cell markers including Stella, MVH and Prdm1. Our study indicates that Dazl is a master gene controlling germ cell differentiation and that ectopic expression of Dazl promotes the dynamic differentiation of mouse ES cells into gametes in vitro.

  7. Cell Centred Database (CCDB)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Cell Centered Database (CCDB) is a web accessible database for high resolution 2D, 3D and 4D data from light and electron microscopy, including correlated...

  8. Thin Solid Oxide Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material, at least one metal and a catalyst...... material, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same. The present invention also relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous...... cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material and a catalyst material, wherein the electrolyte material is doper zirconia, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same...

  9. Mammary epithelial cell

    DEFF Research Database (Denmark)

    Kass, Laura; Erler, Janine Terra; Dembo, Micah;

    2007-01-01

    a repertoire of transmembrane receptors, of which integrins are the best characterized. Integrins modulate cell fate by reciprocally transducing biochemical and biophysical cues between the cell and the extracellular matrix, facilitating processes such as embryonic branching morphogenesis and lactation...... in the mammary gland. During breast development and cancer progression, the extracellular matrix is dynamically altered such that its composition, turnover, processing and orientation change dramatically. These modifications influence mammary epithelial cell shape, and modulate growth factor and hormonal...... responses to regulate processes including branching morphogenesis and alveolar differentiation. Malignant transformation of the breast is also associated with significant matrix remodeling and a progressive stiffening of the stroma that can enhance mammary epithelial cell growth, perturb breast tissue...

  10. Plasma cell leukemia

    DEFF Research Database (Denmark)

    Fernández de Larrea, C; Kyle, R A; Durie, B G M;

    2013-01-01

    Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic......-pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds...... regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem cell transplantation if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding...

  11. Mast cells & Company

    Directory of Open Access Journals (Sweden)

    Friederike eJönsson

    2012-02-01

    Full Text Available Classically, allergy depends on IgE antibodies and on high-affinity IgE receptors expressed by mast cells and basophils. This long accepted IgE/FcεRI/mast cell paradigm, on which the definition of immediate hypersensitivity was based in the Gell and Coomb’s classification, appears too reductionist. Recently accumulated evidence indeed requires that not only IgE but also IgG antibodies, that not only FcεRI but also FcγR of the different types, that not only mast cells and basophils but also neutrophils, monocytes, macrophages, eosinophils, and other myeloid cells by considered as important players in allergy. This view markedly changes our understanding of allergic diseases and, possibly, their treatment.

  12. The Giant Cell.

    Science.gov (United States)

    Stockdale, Dennis

    1998-01-01

    Provides directions for the construction of giant plastic cells, including details for building and installing the organelles. Also contains instructions for preparing the ribosomes, nucleolus, nucleus, and mitochondria. (DDR)

  13. Familial germ cell tumor

    Directory of Open Access Journals (Sweden)

    Sanju Cyriac

    2012-01-01

    Full Text Available Familial testicular germ cell tumors are well known in literature. Only few cases are reported where both brother and sister of the same family suffered from germ cell malignancies. We present a family where the proband is a survivor of ovarian dysgerminoma stage IA. Her elder male sibling became acutely ill and was detected to have disseminated testicular malignancy with grossly elevated markers and vegetations in the mitral valve leaflets. Despite all measures he could not be saved. Presence of germ cell malignancies in the siblings of different sex in the same family points toward a genetic susceptibility. Literature review revealed only six similar cases. A discussion regarding the rare occurrence of familial germ cell malignancies with the affected family members may be worthwhile.

  14. Renal Medullary Interstitial Cells

    Science.gov (United States)

    Rao, Reena; Hao, Chuan-Ming; Breyer, Matthew D.

    2007-04-01

    Renal medullary interstitial cells (RMICs) are specialized fibroblast-like cells that reside in the renal medulla among the vasa recta, the thin limbs of Henle's loop, and medullary collecting ducts. These cells are characterized by abundant lipid droplets in the cytoplasm. The lipid droplets are composed of triglycerides, cholesterol esters and free long-chain fatty acids, including arachidonic acid. RMICs are also a major site of cyclooxygenase2 (COX-2) expression, and thus a major site of COX-2 derived prostanoid biosynthesis. RMICs are also a potential target of hormones such as angiotensin II and endothelin. The RMIC COX-2 expression and the abundance of lipid droplets change with salt and water intake. These properties of RMICs are consistent with an important role of these cells in modulating physiologic and pathologic processes of the kidney.

  15. Langerhans cell histiocytosis

    OpenAIRE

    Xiao-ling YAN

    2014-01-01

    A case report and literature review. We present a boy with a multisystemic presentation of Langerhans cell histiocytosis and severe pulmonary lesion.Skin lesion helped to suspect and confirm diagnosis by scalpbiopsy. Chemotherapy was important for favorable result.

  16. [Pulmonary Langerhans cell histiocytosis].

    Science.gov (United States)

    Popper, H H

    2015-09-01

    Pulmonary Langerhans cell histiocytosis is regarded as a reactive proliferation of the dendritic Langerhans cell population stimulated by chronic tobacco-derived plant proteins due to incomplete combustion but can also occur in childhood as a tumor-like systemic disease. Currently, both these forms cannot be morphologically distinguished. In the lungs a nodular proliferation of Langerhans cells occurs in the bronchial mucosa and also peripherally in the alveolar septa with an accompanying infiltration by eosinophilic granulocytes and destruction of the bronchial wall. Langerhans cells can be selectively detected with antibodies against CD1a and langerin. In the reactive isolated pulmonary form, abstinence from tobacco smoking in most patients leads to regression of infiltration and improvement of symptoms. In high-resolution computed tomography (HRCT) the small star-like scars can still be detected even after complete cessation of tobacco smoking. PMID:26289803

  17. Merkel Cell Carcinoma

    Science.gov (United States)

    ... of the Year Award Arnold P. Gold Foundation Humanism in Medicine Award Diversity Mentorship Program Eugene Van ... 300 PUVA treatments. What causes Merkel cell carcinoma? Scientists are still studying what causes this skin cancer. ...

  18. Sickle cell test

    Science.gov (United States)

    Sickledex; Hgb S test ... This test is done to tell if a person has abnormal hemoglobin that causes sickle cell disease and sickle ... and no symptoms, or only mild ones. This test does not tell the difference between these two ...

  19. Photovoltaic solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Nielson, Gregory N; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J

    2014-05-20

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electricity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  20. Photovoltaic solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

    2013-11-26

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  1. RSW Cell Centered Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — New cell centered grids are generated to complement the node-centered ones uploaded. Six tarballs containing the coarse, medium, and fine mixed-element and pure...

  2. Metaphyseal giant cell tumor

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, L.F.; Hemais, P.M.P.G.; Aymore, I.L.; Carmo, M.C.R. do; Cunha, M.E.P.R. da; Resende, C.M.C.

    Three cases of metaphyseal giant cell tumor are presented. A review of the literature is done, demostrating the lesion is rare and that there are few articles about it. Age incidence and characteristics of the tumor are discussed.

  3. Plasma Cell Cheilitis

    Directory of Open Access Journals (Sweden)

    Thami Gurvinder P

    1999-01-01

    Full Text Available A case of plasma cell cheilitis with good response to glucocorticoids, is described for its rarity and probable aetiological correlation with habit of use of nasal snuff is discussed.

  4. Targeting tumour Cell Plasticity

    Institute of Scientific and Technical Information of China (English)

    Elizabeth D. WILLIAMS

    2009-01-01

    @@ Her research is focused on understanding the mechanisms of tumour progression and metastasis, particularly in uro-logical carcinomas (bladder and prostate). Tumour cell plasticity, including epithelial-mesenchymal transition, is a cen-tral theme in Dr Williams' work.

  5. Mast cells and company.

    Science.gov (United States)

    Jönsson, Friederike; Daëron, Marc

    2012-01-01

    Classically, allergy depends on IgE antibodies and on high-affinity IgE receptors expressed by mast cells and basophils. This long accepted IgE/FcεRI/mast cell paradigm, on which the definition of immediate hypersensitivity was based in the Gell and Coomb's classification, appears too reductionist. Recently accumulated evidence indeed requires that not only IgE but also IgG antibodies, that not only FcεRI but also FcγR of the different types, that not only mast cells and basophils but also neutrophils, monocytes, macrophages, eosinophils, and other myeloid cells be considered as important players in allergy. This view markedly changes our understanding of allergic diseases and, possibly, their treatment.

  6. Metaphyseal giant cell tumor

    International Nuclear Information System (INIS)

    Three cases of metaphyseal giant cell tumor are presented. A review of the literature is done, demostrating the lesion is rare and that there are few articles about it. Age incidence and characteristics of the tumor are discussed. (Author)

  7. Lipocytes (fat cells) (image)

    Science.gov (United States)

    ... to energy output, there is no expansion of fat cells (lipocytes) to accommodate excess. It is only when more calories are taken in than used that the extra fat is stored in the lipocytes and the person ...

  8. CAM and NK Cells

    Directory of Open Access Journals (Sweden)

    Kazuyoshi Takeda

    2004-01-01

    Full Text Available It is believed that tumor development, outgrowth and metastasis are under the surveillance of the immune system. Although both innate and acquired immune systems play roles, innate immunity is the spearhead against tumors. Recent studies have revealed the critical role of natural killer (NK cells in immune surveillance and that NK cell activity is considerably influenced by various agents, such as environmental factors, stress, foods and drugs. Some of these NK cell stimulants have been used in complementary and alternative medicine (CAM since ancient times. Therefore, the value of CAM should be re-evaluated from this point of view. In this review, we overview the intimate correlation between NK cell functions and CAM agents, and discuss possible underlying mechanisms mediating this. In particular, neuro-immune crosstalk and receptors for CAM agents are the most important and interesting candidates for such mechanisms.

  9. Nanodiamond internalization in cells and the cell uptake mechanism

    International Nuclear Information System (INIS)

    Cell type-dependent penetration of nanodiamond in living cells is one of the important factors for using nanodiamond as cellular markers/labels, for drug delivery as well as for other biomedical applications. In this work, internalization of 100 nm nanodiamonds by A549 lung human adenocarcinoma cell, Beas-2b non-tumorigenic human bronchial epithelial cell, and HFL-1 fibroblast-like human fetal lung cell is studied and compared. The penetration of nanodiamond into the cells was observed using confocal fluorescence imaging and Raman imaging methods. Visualization of the nanodiamond in cells allows comparison of the internalization for diamond nanoparticles in cancer A549 cell, non-cancer HFL-1, and Beas-2b cells. The dose-dependent and time-dependent behavior of nanodiamond uptake is observed in both cancer as well as non-cancer cells. The mechanism of nanodiamond uptake by cancer and non-cancer cells is analyzed by blocking different pathways. The uptake of nanodiamond in both cancer and non-cancer cells was found predominantly via clathrin-dependent endocytosis. In spite of observed similarity in the uptake mechanism for cancer and non-cancer cells, the nanodiamond uptake for cancer cell quantitatively exceeds the uptake for non-cancer cells, for the studied cell lines. The observed difference in internalization of nanodiamond by cancer and non-cancer cells is discussed

  10. Nanodiamond internalization in cells and the cell uptake mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Perevedentseva, E. [National Dong Hwa University, Department of Physics (China); Hong, S.-F.; Huang, K.-J. [National Dong Hwa University, Department of Life Sciences (China); Chiang, I.-T.; Lee, C.-Y. [National Dong Hwa University, Department of Physics (China); Tseng, Y.-T. [National Dong Hwa University, Department of Life Sciences (China); Cheng, C.-L., E-mail: clcheng@mail.ndhu.edu.tw [National Dong Hwa University, Department of Physics (China)

    2013-08-15

    Cell type-dependent penetration of nanodiamond in living cells is one of the important factors for using nanodiamond as cellular markers/labels, for drug delivery as well as for other biomedical applications. In this work, internalization of 100 nm nanodiamonds by A549 lung human adenocarcinoma cell, Beas-2b non-tumorigenic human bronchial epithelial cell, and HFL-1 fibroblast-like human fetal lung cell is studied and compared. The penetration of nanodiamond into the cells was observed using confocal fluorescence imaging and Raman imaging methods. Visualization of the nanodiamond in cells allows comparison of the internalization for diamond nanoparticles in cancer A549 cell, non-cancer HFL-1, and Beas-2b cells. The dose-dependent and time-dependent behavior of nanodiamond uptake is observed in both cancer as well as non-cancer cells. The mechanism of nanodiamond uptake by cancer and non-cancer cells is analyzed by blocking different pathways. The uptake of nanodiamond in both cancer and non-cancer cells was found predominantly via clathrin-dependent endocytosis. In spite of observed similarity in the uptake mechanism for cancer and non-cancer cells, the nanodiamond uptake for cancer cell quantitatively exceeds the uptake for non-cancer cells, for the studied cell lines. The observed difference in internalization of nanodiamond by cancer and non-cancer cells is discussed.

  11. Stem cells - biological update and cell therapy progress.

    Science.gov (United States)

    Girlovanu, Mihai; Susman, Sergiu; Soritau, Olga; Rus-Ciuca, Dan; Melincovici, Carmen; Constantin, Anne-Marie; Mihu, Carmen Mihaela

    2015-01-01

    In recent years, the advances in stem cell research have suggested that the human body may have a higher plasticity than it was originally expected. Until now, four categories of stem cells were isolated and cultured in vivo: embryonic stem cells, fetal stem cells, adult stem cells and induced pluripotent stem cells (hiPSCs). Although multiple studies were published, several issues concerning the stem cells are still debated, such as: the molecular mechanisms of differentiation, the methods to prevent teratoma formation or the ethical and religious issues regarding especially the embryonic stem cell research. The direct differentiation of stem cells into specialized cells: cardiac myocytes, neural cells, pancreatic islets cells, may represent an option in treating incurable diseases such as: neurodegenerative diseases, type I diabetes, hematologic or cardiac diseases. Nevertheless, stem cell-based therapies, based on stem cell transplantation, remain mainly at the experimental stages and their major limitation is the development of teratoma and cancer after transplantation. The induced pluripotent stem cells (hiPSCs) represent a prime candidate for future cell therapy research because of their significant self-renewal and differentiation potential and the lack of ethical issues. This article presents an overview of the biological advances in the study of stem cells and the current progress made in the field of regenerative medicine.

  12. Endothelial cells derived from human embryonic stem cells

    Science.gov (United States)

    Levenberg, Shulamit; Golub, Justin S.; Amit, Michal; Itskovitz-Eldor, Joseph; Langer, Robert

    2002-04-01

    Human embryonic stem cells have the potential to differentiate into various cell types and, thus, may be useful as a source of cells for transplantation or tissue engineering. We describe here the differentiation steps of human embryonic stem cells into endothelial cells forming vascular-like structures. The human embryonic-derived endothelial cells were isolated by using platelet endothelial cell-adhesion molecule-1 (PECAM1) antibodies, their behavior was characterized in vitro and in vivo, and their potential in tissue engineering was examined. We show that the isolated embryonic PECAM1+ cells, grown in culture, display characteristics similar to vessel endothelium. The cells express endothelial cell markers in a pattern similar to human umbilical vein endothelial cells, their junctions are correctly organized, and they have high metabolism of acetylated low-density lipoprotein. In addition, the cells are able to differentiate and form tube-like structures when cultured on matrigel. In vivo, when transplanted into SCID mice, the cells appeared to form microvessels containing mouse blood cells. With further studies, these cells could provide a source of human endothelial cells that could be beneficial for potential applications such as engineering new blood vessels, endothelial cell transplantation into the heart for myocardial regeneration, and induction of angiogenesis for treatment of regional ischemia.

  13. Transgelin-2 in B-Cells Controls T-Cell Activation by Stabilizing T Cell - B Cell Conjugates

    Science.gov (United States)

    Chae, Myoung-Won; Kim, Hye-Ran; Kim, Chang-Hyun; Jun, Chang-Duk; Park, Zee-Yong

    2016-01-01

    The immunological synapse (IS), a dynamic and organized junction between T-cells and antigen presenting cells (APCs), is critical for initiating adaptive immunity. The actin cytoskeleton plays a major role in T-cell reorganization during IS formation, and we previously reported that transgelin-2, an actin-binding protein expressed in T-cells, stabilizes cortical F-actin, promoting T-cell activation in response to antigen stimulation. Transgelin-2 is also highly expressed in B-cells, although no specific function has been reported. In this study, we found that deficiency in transgelin-2 (TAGLN2-/-) in B-cells had little effect on B-cell development and activation, as measured by the expression of CD69, MHC class II molecules, and CD80/86. Nevertheless, in B-cells, transgelin-2 accumulated in the IS during the interaction with T-cells. These results led us to hypothesize that transgelin-2 may also be involved in IS stability in B-cells, thereby influencing T-cell function. Notably, we found that transgelin-2 deficiency in B-cells reduced T-cell activation, as determined by the release of IL-2 and interferon-γ and the expression of CD69. Furthermore, the reduced T-cell activation was correlated with reduced B-cell–T-cell conjugate formation. Collectively, these results suggest that actin stability in B-cells during IS formation is critical for the initiation of adaptive T-cell immunity. PMID:27232882

  14. Nonislet Cell Tumor Hypoglycemia

    OpenAIRE

    Johnson Thomas; Salini C. Kumar

    2013-01-01

    Nonislet cell tumor hypoglycemia (NICTH) is a rare cause of hypoglycemia. It is characterized by increased glucose utilization by tissues mediated by a tumor resulting in hypoglycemia. NICTH is usually seen in large mesenchymal tumors including tumors involving the GI tract. Here we will discuss a case, its pathophysiology, and recent advances in the management of NICTH. Our patient was diagnosed with poorly differentiated squamous cell carcinoma of esophagus. He continued to be hypoglycemic ...

  15. Plasma cell leukemia

    OpenAIRE

    Gertz, Moria A.; Buadi, Francis K.

    2010-01-01

    Plasma cell leukemia (PCL) is a rare, yet aggressive plasma cell (PC) neoplasm, variant of multiple myeloma (MM), characterized by high levels of PCs circulating in the peripheral blood. PCL can either originate de novo (primary PCL) or as a secondary leukemic transformation of MM (secondary PCL). Presenting signs and symptoms are similar to those seen in MM such as renal insufficiency, hypercalcemia, lytic bone lesions, anemia, and thrombocytopenia, but can also include hepatomegaly and sple...

  16. Dentinogenic ghost cell tumor

    Directory of Open Access Journals (Sweden)

    Singhaniya Shikha

    2009-01-01

    Full Text Available Dentinogenic ghost cell tumor (DGCT is a rare tumorous form of calcifying odontogenic cyst and only a small number of cases have been described. It is a locally invasive neoplasm that is characterized by ameloblastoma-like epithelial islands, ghost cells and dentinoid. The present report describes a case of a 21-year-old male with a tumor in the posterior region of the mandible, showing features of DGCT.

  17. Parietal cell vagotomy.

    Science.gov (United States)

    Cumberland, V H; Coupland, G A

    1975-07-12

    In a series of 100 consecutive patients who had parietal cell vagotomy performed, no drainage procedure was performed in 56 while 44 were drained. Dumping was significantly less in those who were not drained. All patients were tested for adequacy of vagotomy and for function of the nerve of Latarget at operation. Four patients have had further operations, two for proven recurrent ulcers. Parietal cell vagotomy has given excellent clinical results in this group of patients.

  18. Liquid fuel cells.

    Science.gov (United States)

    Soloveichik, Grigorii L

    2014-01-01

    The advantages of liquid fuel cells (LFCs) over conventional hydrogen-oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented.

  19. NK Cells and Trophoblasts

    OpenAIRE

    Parham, Peter

    2004-01-01

    In placental mammals, viviparity—the production of living young within the mother's body—evolved under the auspices of the immune system. Elements of immunity were incorporated, giving pregnancy a mildly inflammatory character. Formation of the placenta, the organ that feeds the fetus, involves a cooperation between maternal natural killer (NK) cells and fetal trophoblast cells that remodels the blood supply. Recent research reveals that this process and human reproductive success are influen...

  20. Syndecans and cell adhesion

    DEFF Research Database (Denmark)

    Couchman, J R; Chen, L; Woods, A

    2001-01-01

    Now that transmembrane signaling through primary cell-matrix receptors, integrins, is being elucidated, attention is turning to how integrin-ligand interactions can be modulated. Syndecans are transmembrane proteoglycans implicated as coreceptors in a variety of physiological processes, including...... cell adhesion, migration, response to growth factors, development, and tumorigenesis. This review will describe this family of proteoglycans in terms of their structures and functions and their signaling in conjunction with integrins, and indicate areas for future research....

  1. Familial germ cell tumor

    OpenAIRE

    Sanju Cyriac; Rejeev Rajendranath; A. Robert Louis; Sagar, T. G.

    2012-01-01

    Familial testicular germ cell tumors are well known in literature. Only few cases are reported where both brother and sister of the same family suffered from germ cell malignancies. We present a family where the proband is a survivor of ovarian dysgerminoma stage IA. Her elder male sibling became acutely ill and was detected to have disseminated testicular malignancy with grossly elevated markers and vegetations in the mitral valve leaflets. Despite all measures he could not be saved. Presenc...

  2. Langerhans cell histiocytosis

    OpenAIRE

    Aruna, D. R.; G Pushpalatha; Sushma Galgali; Prashanthy,

    2011-01-01

    Langerhans cell histiocytosis (LCH) is a group of rare disorders histologically characterized by the proliferation of Langerhans cells. Multiple organs and systems may be involved by the disease. Typically, there is bone involvement and, less frequently, lesions may be found in the lungs, liver, lymph nodes, skin, and mucosa. Oral soft tissue lesions without bone involvement are rare. We present a case of oral lesions associated with LCH in a young woman.

  3. Pulmonary langerhans cell histiocytosis

    OpenAIRE

    Suri Harpreet S; Yi Eunhee S; Nowakowski Gregorz S; Vassallo Robert

    2012-01-01

    Abstract Pulmonary Langerhans Cell Histiocytosis (PLCH) is a relatively uncommon lung disease that generally, but not invariably, occurs in cigarette smokers. The pathologic hallmark of PLCH is the accumulation of Langerhans and other inflammatory cells in small airways, resulting in the formation of nodular inflammatory lesions. While the overwhelming majority of patients are smokers, mechanisms by which smoking induces this disease are not known, but likely involve a combination of events r...

  4. The Cell Processor

    OpenAIRE

    Hoefler, Torsten

    2006-01-01

    Mainstream processor development is mostly targeted at compatibility and continuity. Thus, the processor market is dominated by x86 compatible CPUs since more than two decades now. Several new concepts tried to gain some market share, but it was not possible to overtake the old compatibility driven concepts. A group of three corporates tries another way to come into the market with a new idea, the cell design. The cell processor is a new try to leverage the increasing amount...

  5. The intestinal stem cell

    OpenAIRE

    Barker, Nick; van de Wetering, Marc; Clevers, Hans

    2008-01-01

    The epithelium of the adult mammalian intestine is in a constant dialog with its underlying mesenchyme to direct progenitor proliferation, lineage commitment, terminal differentiation, and, ultimately, cell death. The epithelium is shaped into spatially distinct compartments that are dedicated to each of these events. While the intestinal epithelium represents the most vigorously renewing adult tissue in mammals, the stem cells that fuel this self-renewal process have been identified only rec...

  6. Intracranial germ cell tumor

    OpenAIRE

    Kreutz, J; Rausin, L.; Weerts, E; Tebache, M; Born, J; Hoyoux, C

    2010-01-01

    Germ cell tumours represent about 3 to 8% of pediatric brain tumours. Occurrence of diabetes insipidus is common in the case of suprasellar germ cell tumors. The diagnosis may be advanced by MRI owing to the location and relatively univocal characteristics of the lesion signal. The existence of a bifocal mass developed in both suprasellar region and pineal zone is highly suggestive of a germinoma. The most important notion is to recognize that at the time of diabetes insipidus diagnosis in a ...

  7. Olfactory ensheathing cell tumor

    Directory of Open Access Journals (Sweden)

    Ippili Kaushal

    2009-01-01

    Full Text Available Olfactory ensheathing cells (OECs are found in the olfactory bulb and olfactory nasal mucosa. They resemble Schwann cells on light and electron microscopy, however, immunohistochemical staining can distinguish between the two. There are less than 30 cases of olfactory groove schwannomas reported in the literature while there is only one reported case of OEC tumor. We report an OEC tumor in a 42-year-old male and discuss the pathology and origin of this rare tumor.

  8. Cell Processing Engineering for Regenerative Medicine : Noninvasive Cell Quality Estimation and Automatic Cell Processing.

    Science.gov (United States)

    Takagi, Mutsumi

    2016-01-01

    The cell processing engineering including automatic cell processing and noninvasive cell quality estimation of adherent mammalian cells for regenerative medicine was reviewed. Automatic cell processing necessary for the industrialization of regenerative medicine was introduced. The cell quality such as cell heterogeneity should be noninvasively estimated before transplantation to patient, because cultured cells are usually not homogeneous but heterogeneous and most protocols of regenerative medicine are autologous system. The differentiation level could be estimated by two-dimensional cell morphology analysis using a conventional phase-contrast microscope. The phase-shifting laser microscope (PLM) could determine laser phase shift at all pixel in a view, which is caused by the transmitted laser through cell, and might be more noninvasive and more useful than the atomic force microscope and digital holographic microscope. The noninvasive determination of the laser phase shift of a cell using a PLM was carried out to determine the three-dimensional cell morphology and estimate the cell cycle phase of each adhesive cell and the mean proliferation activity of a cell population. The noninvasive discrimination of cancer cells from normal cells by measuring the phase shift was performed based on the difference in cytoskeleton density. Chemical analysis of the culture supernatant was also useful to estimate the differentiation level of a cell population. A probe beam, an infrared beam, and Raman spectroscopy are useful for diagnosing the viability, apoptosis, and differentiation of each adhesive cell. PMID:25373455

  9. Mast cells and COPD.

    Science.gov (United States)

    Mortaz, Esmaeil; Folkerts, Gert; Redegeld, Frank

    2011-08-01

    The pathogenesis of chronic obstructive pulmonary disease (COPD) is based on the innate and adaptive inflammatory immune response to the inhalation of toxic particles and gases. Although tobacco smoking is the primary cause of this inhalation injury, many other environmental and occupational exposures contribute to the pathology of COPD. The immune inflammatory changes associated with COPD are linked to a tissue-repair and -remodeling process that increases mucus production and causes emphysematous destruction of the gas-exchanging surface of the lung. The common form of emphysema observed in smokers begins in the respiratory bronchioles near the thickened and narrowed small bronchioles that become the major site of obstruction in COPD. The inflamed airways of COPD patients contain several inflammatory cells including neutrophils, macrophages, T lymphocytes, and dendritic cells. The relative contribution of mast cells to airway injury and remodeling is not well documented. In this review, an overview is given on the possible role of mast cells and their mediators in the pathogenesis of COPD. Activation of mast cells and mast cell signaling in response to exposure to cigarette smoke is further discussed. PMID:21463700

  10. Fuel cell generator

    International Nuclear Information System (INIS)

    A high temperature solid electrolyte fuel cell generator comprising a housing means defining a plurality of chambers including a generator chamber and a combustion products chamber, a porous barrier separating the generator and combustion product chambers, a plurality of elongated annular fuel cells each having a closed end and an open end with the open ends disposed within the combustion product chamber, the cells extending from the open end through the porous barrier and into the generator chamber, a conduit for each cell, each conduit extending into a portion of each cell disposed within the generator chamber, each conduit having means for discharging a first gaseous reactant within each fuel cell, exhaust means for exhausting the combustion product chamber, manifolding means for supplying the first gaseous reactant to the conduits with the manifolding means disposed within the combustion product chamber between the porous barrier and the exhaust means and the manifolding means further comprising support and bypass means for providing support of the manifolding means within the housing while allowing combustion products from the first and a second gaseous reactant to flow past the manifolding means to the exhaust means, and means for flowing the second gaseous reactant into the generator chamber

  11. Turing patterns inside cells.

    Directory of Open Access Journals (Sweden)

    Damián E Strier

    Full Text Available Concentration gradients inside cells are involved in key processes such as cell division and morphogenesis. Here we show that a model of the enzymatic step catalized by phosphofructokinase (PFK, a step which is responsible for the appearance of homogeneous oscillations in the glycolytic pathway, displays Turing patterns with an intrinsic length-scale that is smaller than a typical cell size. All the parameter values are fully consistent with classic experiments on glycolytic oscillations and equal diffusion coefficients are assumed for ATP and ADP. We identify the enzyme concentration and the glycolytic flux as the possible regulators of the pattern. To the best of our knowledge, this is the first closed example of Turing pattern formation in a model of a vital step of the cell metabolism, with a built-in mechanism for changing the diffusion length of the reactants, and with parameter values that are compatible with experiments. Turing patterns inside cells could provide a check-point that combines mechanical and biochemical information to trigger events during the cell division process.

  12. >Effect of progesterone hormon on cell viability and stem cell activation in dental pulp cells

    OpenAIRE

    Segah Altuntaş; Muhammed Ali Kara; Deniz Selin Aksoy; Zehra Dilşad Çoban; Şefik Güran

    2016-01-01

    Objective: The dental pulp is the part in the center of a tooth made up of living connective tissue and cells called odontoblasts. The vitality of the dentin structure, both during health and after injury, depends on pulp cell activity and the signaling processes that regulate the cell’s behavior. Dental pulp tissue has condensed stem cell activity. Dental pulp stem cells are multipotent stem cells that have the potential to differentiate into a variety of cell types. Several publications hav...

  13. On the cell biology of pit cells, the liver-specific NK cells

    Institute of Scientific and Technical Information of China (English)

    Dian Zhong Luo; David Vermijlen; Bülent Ahishali; Vasilis Triantis; Georgia Plakoutsi; Filip Braet; Karin Vanderkerken; Eddie Wisse

    2000-01-01

    @@ INTRODUCTION Natural killer (NK) cells are functionally defined by their ability to kill certain tumor cells and virusinfected cells without prior sensitization[1]. NK cells comprise about 10% to 15% of lymphocytes in the peripheral blood and most of these cells in human and rat have the morphology of large granular lymphocytes ( LGL )[2]. However, recent studies have demonstrated that small agranular lymphocytes, lacking CD3 expression, have cytolytic activity comparable to NK cells[3].

  14. Involvement of Plant Stem Cells or Stem Cell-Like Cells in Dedifferentiation

    OpenAIRE

    Jiang, Fangwei; Feng, Zhenhua; Liu, Hailiang; Zhu, Jian

    2015-01-01

    Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to pro...

  15. Cell Cycle Progression of Human Cells Cultured in Rotating Bioreactor

    Science.gov (United States)

    Parks, Kelsey

    2009-01-01

    Space flight has been shown to alter the astronauts immune systems. Because immune performance is complex and reflects the influence of multiple organ systems within the host, scientists sought to understand the potential impact of microgravity alone on the cellular mechanisms critical to immunity. Lymphocytes and their differentiated immature form, lymphoblasts, play an important and integral role in the body's defense system. T cells, one of the three major types of lymphocytes, play a central role in cell-mediated immunity. They can be distinguished from other lymphocyte types, such as B cells and natural killer cells by the presence of a special receptor on their cell surface called T cell receptors. Reported studies have shown that spaceflight can affect the expression of cell surface markers. Cell surface markers play an important role in the ability of cells to interact and to pass signals between different cells of the same phenotype and cells of different phenotypes. Recent evidence suggests that cell-cycle regulators are essential for T-cell function. To trigger an effective immune response, lymphocytes must proliferate. The objective of this project is to investigate the changes in growth of human cells cultured in rotating bioreactors and to measure the growth rate and the cell cycle distribution for different human cell types. Human lymphocytes and lymphoblasts will be cultured in a bioreactor to simulate aspects of microgravity. The bioreactor is a cylindrical culture vessel that incorporates the aspects of clinostatic rotation of a solid fluid body around a horizontal axis at a constant speed, and compensates gravity by rotation and places cells within the fluid body into a sustained free-fall. Cell cycle progression and cell proliferation of the lymphocytes will be measured for a number of days. In addition, RNA from the cells will be isolated for expression of genes related in cell cycle regulations.

  16. Cell supermarket: Adipose tissue as a source of stem cells

    Science.gov (United States)

    Adipose tissue is derived from numerous sources, and in recent years has been shown to provide numerous cells from what seemingly was a population of homogeneous adipocytes. Considering the types of cells that adipose tissue-derived cells may form, these cells may be useful in a variety of clinical ...

  17. Stabilization Of Apoptotic Cells: Generation Of Zombie Cells

    Directory of Open Access Journals (Sweden)

    José A. Sánchez Alcázar

    2015-08-01

    Stabilization of apoptotic cells can be used for reliable detection and quantification of apoptosis in cultured cells and may allow a safer administration of apoptotic cells in clinical applications. Furthermore, it opens new avenues in the functional reconstruction of apoptotic cells for longer preservation.

  18. CellTracks cytometer for detection of circulating tumor cells

    NARCIS (Netherlands)

    Tibbe, A.G.J.; Kooi, van der A.; Groot, de M.R.; Vermes, I.

    2003-01-01

    Introduction: In patients with carcinomas, tumor cells are shed into the circulation. The number of the circulating tumor cells is low and technology is needed that has sufficient sensitivity and specificity to enumerate and characterize these cells. The CellTracks system was developed to provide an

  19. Recognition and Regulation of T Cells by NK Cells

    Science.gov (United States)

    Pallmer, Katharina; Oxenius, Annette

    2016-01-01

    Regulation of T cell responses by innate lymphoid cells (ILCs) is increasingly documented and studied. Direct or indirect crosstalk between ILCs and T cells early during and after T cell activation can affect their differentiation, polarization, and survival. Natural killer (NK) cells that belong to the ILC1 group were initially described for their function in recognizing and eliminating “altered self” and as source of early inflammatory cytokines, most notably type II interferon. Using signals conveyed by various germ-line encoded activating and inhibitory receptors, NK cells are geared to sense sudden cellular changes that can be caused by infection events, malignant transformation, or cellular stress responses. T cells, when activated by TCR engagement (signal 1), costimulation (signal 2), and cytokines (signal 3), commit to a number of cellular alterations, including entry into rapid cell cycling, metabolic changes, and acquisition of effector functions. These abrupt changes may alert NK cells, and T cells might thereby expose themselves as NK cell targets. Here, we review how activated T cells can be recognized and regulated by NK cells and what consequences such regulation bears for T cell immunity in the context of vaccination, infection, or autoimmunity. Conversely, we will discuss mechanisms by which activated T cells protect themselves against NK cell attack and outline the significance of this safeguard mechanism. PMID:27446081

  20. Sponge cell culture? A molecular identification method for sponge cells

    NARCIS (Netherlands)

    Sipkema, D.; Heilig, G.H.J.; Akkermans, A.D.L.; Osinga, R.; Tramper, J.; Wijffels, R.H.

    2003-01-01

    Dissociated sponge cells are easily confused with unicellular organisms. This has been an obstacle in the development of sponge-cell lines. We developed a molecular detection method to identify cells of the sponge Dysidea avara in dissociated cell cultures. The 18S ribosomal RNA gene from a Dysidea

  1. Cell culture models for study of differentiated adipose cells

    OpenAIRE

    Clynes, Martin

    2014-01-01

    Adipose cells are an important source of mesenchymal stem cells and are important for direct use in research on lipid metabolism and obesity. In addition to use of primary cultures, there is increasing interest in other sources of larger numbers of cells, using approaches including induced pluripotent stem cell differentiation and viral immortalisation.

  2. Generation of pancreatic islet cells from human embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG DongHui; JIANG Wei; SHI Yan; DENG HongKui

    2009-01-01

    Efficiently obtaining functional pancreaUc islet cells derived from human embryonic stem (hES) cells not only provides great potential to solve the shortage of islets sources for type I diabetes cell therapy,but also benefits the study of the development of the human pancreas and diabetes pathology. In 2001,hES cells were reported to have the capacity to generate insulin-producing cells by spontaneous differentiation in vitro. Since then, many strategies (such as overexpression of key transcription factors,delivery of key proteins for pancreatic development, co-transplantation of differentiated hES cells along with fetal pancreas, stepwise differentiation by mimicking in vivo pancreatic development) have been employed in order to induce the differentiation of pancreatic islet cells from hES cells. Moreover, patient-specific induced pluripotent stem (iPS) cells can be generated by reprogramming somatic cells.iPS cells have characteristics similar to those of ES cells and offer a new cell source for type I diabetes cell therapy that reduces the risk of immunologic rejection. In this review, we summarize the recent progress made in the differentiation of hES and iPS cells into functional pancreatic islet cells and discuss the challenges for their future study.

  3. Generation of pancreatic islet cells from human embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Efficiently obtaining functional pancreatic islet cells derived from human embryonic stem(hES) cells not only provides great potential to solve the shortage of islets sources for type I diabetes cell therapy,but also benefits the study of the development of the human pancreas and diabetes pathology.In 2001,hES cells were reported to have the capacity to generate insulin-producing cells by spontaneous differentiation in vitro.Since then,many strategies(such as overexpression of key transcription factors,delivery of key proteins for pancreatic development,co-transplantation of differentiated hES cells along with fetal pancreas,stepwise differentiation by mimicking in vivo pancreatic development) have been employed in order to induce the differentiation of pancreatic islet cells from hES cells.Moreover,patient-specific induced pluripotent stem(iPS) cells can be generated by reprogramming somatic cells.iPS cells have characteristics similar to those of ES cells and offer a new cell source for type I diabetes cell therapy that reduces the risk of immunologic rejection.In this review,we summarize the recent progress made in the differentiation of hES and iPS cells into functional pancreatic islet cells and discuss the challenges for their future study.

  4. Determinants of leader cells in collective cell migration.

    NARCIS (Netherlands)

    Khalil, A.; Friedl, P.H.A.

    2010-01-01

    Collective migration is a basic mechanism of cell translocation during morphogenesis, wound repair and cancer invasion. Collective movement requires cells to retain cell-cell contacts, exhibit group polarization with defined front-rear asymmetry, and consequently move as one multicellular unit. Depe

  5. Programmed cell death and cell extrusion in rat duodenum

    DEFF Research Database (Denmark)

    Schauser, Kirsten; Larsson, Lars-Inge

    2005-01-01

    The small intestinal epithelium is continously renewed through a balance between cell division and cell loss. How this balance is achieved is uncertain. Thus, it is unknown to what extent programmed cell death (PCD) contributes to intestinal epithelial cell loss. We have used a battery of techniq...

  6. Glioma cell dispersion is driven by α5 integrin-mediated cell-matrix and cell-cell interactions.

    Science.gov (United States)

    Blandin, Anne-Florence; Noulet, Fanny; Renner, Guillaume; Mercier, Marie-Cécile; Choulier, Laurence; Vauchelles, Romain; Ronde, Philippe; Carreiras, Franck; Etienne-Selloum, Nelly; Vereb, Gyorgy; Lelong-Rebel, Isabelle; Martin, Sophie; Dontenwill, Monique; Lehmann, Maxime

    2016-07-01

    Glioblastoma multiform (GBM) is the most common and most aggressive primary brain tumor. The fibronectin receptor, α5 integrin is a pertinent novel therapeutic target. Despite numerous data showing that α5 integrin support tumor cell migration and invasion, it has been reported that α5 integrin can also limit cell dispersion by increasing cell-cell interaction. In this study, we showed that α5 integrin was involved in cell-cell interaction and gliomasphere formation. α5-mediated cell-cell cohesion limited cell dispersion from spheroids in fibronectin-poor microenvironment. However, in fibronectin-rich microenvironment, α5 integrin promoted cell dispersion. Ligand-occupied α5 integrin and fibronectin were distributed in fibril-like pattern at cell-cell junction of evading cells, forming cell-cell fibrillar adhesions. Activated focal adhesion kinase was not present in these adhesions but was progressively relocalized with α5 integrin as cell migrates away from the spheroids. α5 integrin function in GBM appears to be more complex than previously suspected. As GBM overexpressed fibronectin, it is most likely that in vivo, α5-mediated dissemination from the tumor mass overrides α5-mediated tumor cell cohesion. In this respect, α5-integrin antagonists may be useful to limit GBM invasion in brain parenchyma. PMID:27063097

  7. Bone marrow cells differentiation into organ cells using stem cell therapy.

    Science.gov (United States)

    Yang, Y-J; Li, X-L; Xue, Y; Zhang, C-X; Wang, Y; Hu, X; Dai, Q

    2016-07-01

    Bone marrow cells (BMC) are progenitors of bone, cartilage, skeletal tissue, the hematopoiesis-supporting stroma and adipocyte cells. BMCs have the potential to differentiate into neural cells, cardiac myocytes, liver hepatocytes, chondrocytes, renal, corneal, blood, and myogenic cells. The bone marrow cell cultures from stromal and mesenchymal cells are called multipotent adult progenitor cells (MAPCs). MAPCs can differentiate into mesenchymal cells, visceral mesoderm, neuroectoderm and endoderm in vitro. It has been shown that the stem cells derived from bone marrow cells (BMCs) can regenerate cardiac myocytes after myocardial infarction (MI). Adult bone marrow mesenchymal stem cells have the ability to regenerate neural cells. Neural stem/progenitor cells (NS/PC) are ideal for treating central nervous system (CNS) diseases, such as Alzheimer's, Parkinson's and Huntington disease. However, there are important ethical issues about the therapeutic use of stem cells. Neurons, cardiac myocytes, hepatocytes, renal cells, blood cells, chondrocytes and adipocytes regeneration from BMCs are very important in disease control. It is known that limbal epithelial stem cells in the cornea can repair the eye sight and remove symptoms of blindness. Stem cell therapy (SCT) is progressing well in animal models, but the use of SCT in human remains to be explored further.

  8. β-Cell regeneration through the transdifferentiation of pancreatic cells: Pancreatic progenitor cells in the pancreas.

    Science.gov (United States)

    Kim, Hyo-Sup; Lee, Moon-Kyu

    2016-05-01

    Pancreatic progenitor cell research has been in the spotlight, as these cells have the potential to replace pancreatic β-cells for the treatment of type 1 and 2 diabetic patients with the absence or reduction of pancreatic β-cells. During the past few decades, the successful treatment of diabetes through transplantation of the whole pancreas or isolated islets has nearly been achieved. However, novel sources of pancreatic islets or insulin-producing cells are required to provide sufficient amounts of donor tissues. To overcome this limitation, the use of pancreatic progenitor cells is gaining more attention. In particular, pancreatic exocrine cells, such as duct epithelial cells and acinar cells, are attractive candidates for β-cell regeneration because of their differentiation potential and pancreatic lineage characteristics. It has been assumed that β-cell neogenesis from pancreatic progenitor cells could occur in pancreatic ducts in the postnatal stage. Several studies have shown that insulin-producing cells can arise in the duct tissue of the adult pancreas. Acinar cells also might have the potential to differentiate into insulin-producing cells. The present review summarizes recent progress in research on the transdifferentiation of pancreatic exocrine cells into insulin-producing cells, especially duct and acinar cells. PMID:27330712

  9. Border cells versus border-like cells: are they alike?

    Science.gov (United States)

    Driouich, Azeddine; Durand, Caroline; Cannesan, Marc-Antoine; Percoco, Giuseppe; Vicré-Gibouin, Maité

    2010-09-01

    Roots of many plants are known to produce large numbers of 'border' cells that play a central role in root protection and the interaction of the root with the rhizosphere. Unlike border cells, border-like cells were described only recently in the model plant Arabidopsis thaliana and other Brassicaceae species and very little is known about the functional properties of border-like cells as compared with 'classical' border cells. To stimulate discussion and future research on this topic, the function of border cells and the way border-like cells are organized, maintained, and possibly involved in plant protection is discussed here.

  10. Single Cell Oncogenesis

    Science.gov (United States)

    Lu, Xin

    It is believed that cancer originates from a single cell that has gone through generations of evolution of genetic and epigenetic changes that associate with the hallmarks of cancer. In some cancers such as various types of leukemia, cancer is clonal. Yet in other cancers like glioblastoma (GBM), there is tremendous tumor heterogeneity that is likely to be caused by simultaneous evolution of multiple subclones within the same tissue. It is obvious that understanding how a single cell develops into a clonal tumor upon genetic alterations, at molecular and cellular levels, holds the key to the real appreciation of tumor etiology and ultimate solution for therapeutics. Surprisingly very little is known about the process of spontaneous tumorigenesis from single cells in human or vertebrate animal models. The main reason is the lack of technology to track the natural process of single cell changes from a homeostatic state to a progressively cancerous state. Recently, we developed a patented compound, photoactivatable (''caged'') tamoxifen analogue 4-OHC and associated technique called optochemogenetic switch (OCG switch), which we believe opens the opportunity to address this urgent biological as well as clinical question about cancer. We propose to combine OCG switch with genetically engineered mouse models of head and neck squamous cell carcinoma and high grade astrocytoma (including GBM) to study how single cells, when transformed through acute loss of tumor suppressor genes PTEN and TP53 and gain of oncogenic KRAS, can develop into tumor colonies with cellular and molecular heterogeneity in these tissues. The abstract is for my invited talk in session ``Beyond Darwin: Evolution in Single Cells'' 3/18/2016 11:15 AM.

  11. Cell cycle and cell signal transduction in marine phytoplankton

    Institute of Scientific and Technical Information of China (English)

    LIU Jingwen; JIAO Nianzhi; CAI Huinong

    2006-01-01

    As unicellular phytoplankton, the growth of a marine phytoplankton population results directly from the completion of a cell cycle, therefore, cell-environment communication is an important way which involves signal transduction pathways to regulate cell cycle progression and contribute to growth, metabolism and primary production and respond to their surrounding environment in marine phytoplankton. Cyclin-CDK and CaM/Ca2+ are essentially key regulators in control of cell cycle and signal transduction pathway, which has important values on both basic research and applied biotechnology. This paper reviews progress made in this research field, which involves the identification and characterization of cyclins and cell signal transduction system, cell cycle control mechanisms in marine phytoplankton cells, cell cycle proteins as a marker of a terminal event to estimate the growth rate of phytoplankton at the species level, cell cycle-dependent toxin production of toxic algae and cell cycle progression regulated by environmental factors.

  12. Asymmetric cell division during T cell development controls downstream fate

    Science.gov (United States)

    Pham, Kim; Shimoni, Raz; Charnley, Mirren; Ludford-Menting, Mandy J.; Hawkins, Edwin D.; Ramsbottom, Kelly; Oliaro, Jane; Izon, David; Ting, Stephen B.; Reynolds, Joseph; Lythe, Grant; Molina-Paris, Carmen; Melichar, Heather; Robey, Ellen; Humbert, Patrick O.; Gu, Min

    2015-01-01

    During mammalian T cell development, the requirement for expansion of many individual T cell clones, rather than merely expansion of the entire T cell population, suggests a possible role for asymmetric cell division (ACD). We show that ACD of developing T cells controls cell fate through differential inheritance of cell fate determinants Numb and α-Adaptin. ACD occurs specifically during the β-selection stage of T cell development, and subsequent divisions are predominantly symmetric. ACD is controlled by interaction with stromal cells and chemokine receptor signaling and uses a conserved network of polarity regulators. The disruption of polarity by deletion of the polarity regulator, Scribble, or the altered inheritance of fate determinants impacts subsequent fate decisions to influence the numbers of DN4 cells arising after the β-selection checkpoint. These findings indicate that ACD enables the thymic microenvironment to orchestrate fate decisions related to differentiation and self-renewal. PMID:26370500

  13. Cell proliferation alterations in Chlorella cells under stress conditions

    International Nuclear Information System (INIS)

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  14. Cell proliferation alterations in Chlorella cells under stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rioboo, Carmen [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); O' Connor, Jose Enrique [Laboratorio de Citomica, Unidad Mixta de Investigacion CIPF-UVEG, Centro de Investigacion Principe Felipe, Avda. Autopista del Saler, 16, 46013 Valencia (Spain); Prado, Raquel; Herrero, Concepcion [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); Cid, Angeles, E-mail: cid@udc.es [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain)

    2009-09-14

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  15. Regulation of Hematopoietic Stem Cells by Bone Marrow Stromal Cells

    OpenAIRE

    Anthony, Bryan; Link, Daniel C.

    2013-01-01

    Hematopoietic stem cells (HSCs) reside in specialized microenvironments (niches) in the bone marrow. The stem cell niche is thought to provide signals that support key HSC properties, including self-renewal capacity and long-term multilineage repopulation ability. The stromal cells that comprise the stem cell niche and the signals that they generate that support HSC function are the subjects of intense investigation. Here we review the complex and diverse stromal cell populations that reside ...

  16. Cell mechanics of alveolar epithelial cells (AECs) and macrophages (AMs).

    OpenAIRE

    Féréol, Sophie; Fodil, Redouane; Pelle, Gabriel; Louis, Bruno; Isabey, Daniel

    2008-01-01

    Cell mechanics provides an integrated view of many biological phenomena which are intimately related to cell structure and function. Because breathing constitutes a sustained motion synonymous with life, pulmonary cells are normally designed to support permanent cyclic stretch without breaking, while receiving mechanical cues from their environment. The authors study the mechanical responses of alveolar cells, namely epithelial cells and macrophages, exposed to well-controlled mechanical stre...

  17. Running with neighbors: coordinating cell migration and cell-cell adhesion.

    Science.gov (United States)

    Collins, Caitlin; Nelson, W James

    2015-10-01

    Coordinated movement of large groups of cells is required for many biological processes, such as gastrulation and wound healing. During collective cell migration, cell-cell and cell-extracellular matrix (ECM) adhesions must be integrated so that cells maintain strong interactions with neighboring cells and the underlying substratum. Initiation and maintenance of cadherin adhesions at cell-cell junctions and integrin-based cell-ECM adhesions require integration of mechanical cues, dynamic regulation of the actin cytoskeleton, and input from specific signaling cascades, including Rho family GTPases. Here, we summarize recent advances made in understanding the interplay between these pathways at cadherin-based and integrin-based adhesions during collective cell migration and highlight outstanding questions that remain in the field. PMID:26201843

  18. Innovative Tools and Technology for Analysis of Single Cells and Cell-Cell Interaction.

    Science.gov (United States)

    Konry, Tania; Sarkar, Saheli; Sabhachandani, Pooja; Cohen, Noa

    2016-07-11

    Heterogeneity in single-cell responses and intercellular interactions results from complex regulation of cell-intrinsic and environmental factors. Single-cell analysis allows not only detection of individual cellular characteristics but also correlation of genetic content with phenotypic traits in the same cell. Technological advances in micro- and nanofabrication have benefited single-cell analysis by allowing precise control of the localized microenvironment, cell manipulation, and sensitive detection capabilities. Additionally, microscale techniques permit rapid, high-throughput, multiparametric screening that has become essential for -omics research. This review highlights innovative applications of microscale platforms in genetic, proteomic, and metabolic detection in single cells; cell sorting strategies; and heterotypic cell-cell interaction. We discuss key design aspects of single-cell localization and isolation in microfluidic systems, dynamic and endpoint analyses, and approaches that integrate highly multiplexed detection of various intracellular species. PMID:26928209

  19. Innovative Tools and Technology for Analysis of Single Cells and Cell-Cell Interaction.

    Science.gov (United States)

    Konry, Tania; Sarkar, Saheli; Sabhachandani, Pooja; Cohen, Noa

    2016-07-11

    Heterogeneity in single-cell responses and intercellular interactions results from complex regulation of cell-intrinsic and environmental factors. Single-cell analysis allows not only detection of individual cellular characteristics but also correlation of genetic content with phenotypic traits in the same cell. Technological advances in micro- and nanofabrication have benefited single-cell analysis by allowing precise control of the localized microenvironment, cell manipulation, and sensitive detection capabilities. Additionally, microscale techniques permit rapid, high-throughput, multiparametric screening that has become essential for -omics research. This review highlights innovative applications of microscale platforms in genetic, proteomic, and metabolic detection in single cells; cell sorting strategies; and heterotypic cell-cell interaction. We discuss key design aspects of single-cell localization and isolation in microfluidic systems, dynamic and endpoint analyses, and approaches that integrate highly multiplexed detection of various intracellular species.

  20. Cell Culturing of Cytoskeleton

    Science.gov (United States)

    2004-01-01

    Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. Cell culturing, such as this bone cell culture, is an important part of biomedical research. The BioDyn payload includes a tissue engineering investigation. The commercial affiliate, Millenium Biologix, Inc. has been conducting bone implant experiments to better understand how synthetic bone can be used to treat bone-related illnesses and bone damaged in accidents. On STS-95, the BioDyn payload will include a bone cell culture aimed to help develop this commercial synthetic bone product. Millenium Biologix, Inc. is exploring the potential for making human bone implantable materials by seeding its proprietary artificial scaffold material with human bone cells. The product of this tissue engineering experiment using the Bioprocessing Modules (BPMs) on STS-95 is space-grown bone implants, which could have potential for dental implants, long bone grafts, and coating for orthopedic implants such as hip replacements.

  1. Alkaline fuel cells applications

    Science.gov (United States)

    Kordesch, Karl; Hacker, Viktor; Gsellmann, Josef; Cifrain, Martin; Faleschini, Gottfried; Enzinger, Peter; Fankhauser, Robert; Ortner, Markus; Muhr, Michael; Aronson, Robert R.

    On the world-wide automobile market technical developments are increasingly determined by the dramatic restriction on emissions as well as the regimentation of fuel consumption by legislation. Therefore there is an increasing chance of a completely new technology breakthrough if it offers new opportunities, meeting the requirements of resource preservation and emission restrictions. Fuel cell technology offers the possibility to excel in today's motive power techniques in terms of environmental compatibility, consumer's profit, costs of maintenance and efficiency. The key question is economy. This will be decided by the costs of fuel cell systems if they are to be used as power generators for future electric vehicles. The alkaline hydrogen-air fuel cell system with circulating KOH electrolyte and low-cost catalysed carbon electrodes could be a promising alternative. Based on the experiences of Kordesch [K. Kordesch, Brennstoffbatterien, Springer, Wien, 1984, ISBN 3-387-81819-7; K. Kordesch, City car with H 2-air fuel cell and lead-battery, SAE Paper No. 719015, 6th IECEC, 1971], who operated a city car hybrid vehicle on public roads for 3 years in the early 1970s, improved air electrodes plus new variations of the bipolar stack assembly developed in Graz are investigated. Primary fuel choice will be a major issue until such time as cost-effective, on-board hydrogen storage is developed. Ammonia is an interesting option. The whole system, ammonia dissociator plus alkaline fuel cell (AFC), is characterised by a simple design and high efficiency.

  2. The Lamportian cell wall

    Energy Technology Data Exchange (ETDEWEB)

    Keiliszewski, M.; Lamport, D. (Michigan State Univ. Plant Research Lab., East Lansing (United States))

    1991-05-01

    The Lamportian Warp-Weft hypothesis suggests a cellulose-extensin interpenetrating network where extensin mechanically couples the load-bearing cellulose microfibrils in a wall matrix that is best described as a microcomposite. This model is based on data gathered from the extensin-rich walls of tomato and sycamore cell suspension culture, wherein extensin precursors are insolubilized into the wall by undefined crosslinks. The authors recent work with cell walls isolated from intact tissue as well as walls from suspension cultured cells of the graminaceous monocots maize and rice, the non-graminaceous monocot asparagus, the primitive herbaceous dicot sugar beet, and the gymnosperm Douglas Fir indicate that although extensins are ubiquitous to all plant species examined, they are not the major structural protein component of most walls examined. Amino acid analyses of intact and HF-treated walls shows a major component neither an HRGP, nor directly comparable to the glycine-rich wall proteins such as those associated with seed coat walls or the 67 mole% glycine-rich proteins cloned from petunia and soybean. Clearly, structural wall protein alternatives to extensin exist and any cell wall model must take that into account. If we assume that extracellular matrices are a priori network structures, then new Hypless' structural proteins in the maize cell wall raise questions about the sort of network these proteins create: the kinds of crosslinks involved; how they are formed; and the roles played by the small amounts of HRGPs.

  3. Carbon nanotube solar cells.

    Directory of Open Access Journals (Sweden)

    Colin Klinger

    Full Text Available We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabricate using a spray-paint technique. We observe that cells with a lower concentration of carbon nanotubes on the active semiconducting electrode perform better than cells with a higher concentration of nanotubes. This effect is contrary to the expectation that a larger number of nanotubes would lead to more photoconversion and therefore more power generation. We attribute this to the presence of metallic nanotubes that provide a short for photo-excited electrons, bypassing the load. We demonstrate optimization strategies that improve cell efficiency by orders of magnitude. Once it is possible to make semiconducting-only carbon nanotube films, that may provide the greatest efficiency improvement.

  4. Pituitary cells in space

    Science.gov (United States)

    Hymer, W. C.; Shellenberger, K.; Grindeland, R.

    1994-01-01

    Cells of the mammalian pituitary gland synthesize and secrete several protein hormones which regulate a number of organ systems throughout the body. These include the musculoskeletal, immune, vascular and endocrine systems. Since changes occur in these tissues as a result of spaceflight, and since pituitary growth hormone (GH) and prolactin (PRL) play a role in the control of these systems on earth, we have focused attention over the last 10 years on GH and PRL cell function during and after spaceflight. The cumulative results of 4 spaceflight missions and several mimicked microgravity experiments establish 1) that production and release of biologically active GH and PRL is repeatedly and significantly attenuated (usually >50%) and 2) that changes in cell morphology also occur. In this paper we describe our results within the framework of methodologies and approaches frequently used to study pituitary cell function on earth. In so doing we hope to develop future flight experiments aimed at uncovering possible microgravity 'sensing systems' within the pituitary cell.

  5. Limbal stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Fernandes Merle

    2004-01-01

    Full Text Available The past two decades have witnessed remarkable progress in limbal stem cell transplantation. In addition to harvesting stem cells from a cadaver or a live related donor, it is now possible to cultivate limbal stem cells in vitro and then transplant them onto the recipient bed. A clear understanding of the basic disease pathology and a correct assessment of the extent of stem cell deficiency are essential. A holistic approach towards management of limbal stem cell deficiency is needed. This also includes management of the underlying systemic disease, ocular adnexal pathology and dry eye. Conjunctival limbal autografts from the healthy contralateral eye are performed for unilateral cases. In bilateral cases, tissue may be harvested from a cadaver or a living related donor; prolonged immunosuppression is needed to avoid allograft rejection in such cases. This review describes the surgical techniques, postoperative treatment regimes (including immunosuppression for allografts, the complications and their management. The short and long-term outcomes of the various modalities reported in the literature are also described.

  6. Seeing Cells on the Web

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    Cells are the fundamental unit of life and disease; therefore, many avenues of research converge on cells, making images of cells prominent in research and teaching. Much of the progress of modern biomedical science can be tied to advances in our ability to better visualize the functional morphology of cells, including higher resolution imaging,…

  7. Stem cell organization in Arabidopsis

    NARCIS (Netherlands)

    Wendrich, J.R.

    2016-01-01

    Growth of plant tissues and organs depends on continuous production of new cells, by niches of stem cells. Stem cells typically divide to give rise to one differentiating daughter and one non-differentiating daughter. This constant process of self-renewal ensures that the niches of stem cells or mer

  8. Seventh Edition Fuel Cell Handbook

    Energy Technology Data Exchange (ETDEWEB)

    NETL

    2004-11-01

    Provides an overview of fuel cell technology and research projects. Discusses the basic workings of fuel cells and their system components, main fuel cell types, their characteristics, and their development status, as well as a discussion of potential fuel cell applications.

  9. The generation of sex cells

    OpenAIRE

    Deglincerti, Alessia; Brivanlou, Ali H.

    2015-01-01

    Primordial germ cells (PGCs) are the earliest population of germ cells established during embryonic development and constitute the beginning of the totipotent state. A recent study provides a new protocol for the efficient generation of PGC-like cells from human embryonic stem cells, providing an in vitro platform to study human PGC differentiation and specification.

  10. Stem Cell Transplants (For Parents)

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy Stem Cell Transplants KidsHealth > For Parents > Stem Cell Transplants Print A A A Text Size What's ... Recovery Coping en español Trasplantes de células madre Stem cells are cells in the body that have the ...

  11. Indeterminate cell histocytosis with naïve cells

    Directory of Open Access Journals (Sweden)

    Sheren F Younes

    2013-02-01

    Full Text Available Histiocytoses are a heterogeneous group of disorders characterized by proliferation and accumulation of cells of mononuclearmacrophage system and dendritic cells. Histiocytoses are categorized according to the cell of origin into Langerhans cell histiocytosis (LCH, Non Langerhans cell histiocytoses and indeterminate cell histiocytosis (ICH. ICH is an extraordinary rare neoplastic dendritic cell disorder that has poorly understood histogenesis and pathogenesis. It is characterized by a proliferation of dendritic cells, which mimic Langerhans cells immunophenotypically (positive for CD1a and S-100 protein, but lack Birbeck granules characteristic of Langerhans cells. Twenty-four year-old Egyptian male was presented with reddish brown chest wall nodule. Clinical, histopathological, immunohistochemical and ultrastructure features are typical for ICH. He was in a good state without any evidence of recurrence or metastasis after 24 months follow up. Peculiar histopathological features were detected in the present case. Many unidentified cells with Hematoxylin & Eosin Langerhans like features showed negative staining for S-100, CD1a, Langerin and CD68. In absence of cellular atypia and mitosis, the infiltrating cells showed epidermotropism that was reported once in ICH as well as neural and perineural invasion that were not previously reported. Therefore we prefer using a tentatively designated diagnosis; dendritic cell tumor, not otherwise specified or newly proposed diagnosis (Indeterminate cell histocytosis with naïve cells for the present case.

  12. Dedifferentiated fat cells: A cell source for regenerative medicine

    Institute of Scientific and Technical Information of China (English)

    Medet; Jumabay; Kristina; I; Bostr?m

    2015-01-01

    The identification of an ideal cell source for tissue regeneration remains a challenge in the stem cell field. The ability of progeny cells to differentiate into other cell types is important for the processes of tissue reconstruction and tissue engineering and has clinical, biochemical or molecular implications. The adaptation of stem cells from adipose tissue for use in regenerative medicine has created a new role for adipocytes. Mature adipocytes can easily be isolated from adipose cell suspensions and allowed to dedifferentiate into lipidfree multipotent cells, referred to as dedifferentiated fat(DFAT) cells. Compared to other adult stem cells, the DFAT cells have unique advantages in their abundance, ease of isolation and homogeneity. Under proper condition in vitro and in vivo, the DFAT cells have exhibited adipogenic, osteogenic, chondrogenic, cardiomyogenc, angiogenic, myogenic, and neurogenic potentials. In this review, we first discuss the phenomena of dedifferentiation and transdifferentiation of cells, and then dedifferentiation of adipocytes in particular. Understanding the dedifferentiation process itself may contribute to our knowledge of normal growth processes, as well as mechanisms of disease. Second, we highlight new developments in DFAT cell culture and summarize the current understanding of DFAT cell properties. The unique features of DFAT cells are promising for clinical applications such as tissue regeneration.

  13. New high-speed cell sorting methods for stem cell sorting and breast cancer cell purging

    Science.gov (United States)

    Leary, James F.; McLaughlin, Scott R.; Hokanson, James A.; Rosenblatt, Judah I.

    1998-04-01

    An important problem in clinical medicine is that of positively selecting hematopoietic stem cells or mobilized peripheral blood stem cells for autologous bone marrow transplantation while purging it of contaminating tumor cells. Since both the stem cells to be positively selected and the tumor cells to be purged are relatively rare cells, this poses special problems for their isolation in terms of purity and yield of stem cells, with a high penalty of misclassification for contaminating tumor cells. A model system of tumor cells spiked into bone marrow or blood cells was used to validate the system. Multiparameter data mixtures of human MCF-7 breast cancer cells and human peripheral blood or bone marrow cells were first analyzed by discriminant function analysis. Mathematical methods were developed to assess the relative probabilities of misclassification. Cell identification tags, implemented as additional correlated listmode parameters not used for these analyses, were used to uniquely identify each cell type and to compare classifier results. The performance of classifier systems was also assessed using ROC (`receiver operating characteristics') analysis. Then the classification system was implemented using lookup tables allowing for real-time (in this system approximately 625 microseconds) rapid separation of these cell types. Isolated cell types, purities and yields were assessed by single-cell PCR molecular characterizations.

  14. Enrichment and Function Research of Large Cell Lung Cancer Stem Cell-like Cells

    Directory of Open Access Journals (Sweden)

    Wenke YUE

    2011-06-01

    Full Text Available Background and objective There are no universal method to recognize and screen for lung cancer stem cell markers and indicators. Commonly used methods are flow Cytometry and learning from other cancer stem cell sorting tags to sort lung cancer stem cells. But this method has low specificity screening, the workload is huge. In this study, Serum-free suspension culture was used to enrich lung cancer stem cells, and explore method for lung cancer stem cell screening. Methods Human large lung cancer cell line-L9981 was cultured in serum-free and growth factors added medium, and spheres were obtained. Then the morphological differences of sphere cells and adherent L9981 cells cultured in serum-containing mediums are observed. Cell proliferation was analyzed by Vi-cell viability analyzer; invasion ability was tested by transwell assay; and in vivo tumorigenicity of the two groups of cells was studied in nude mouse. Results Compared with adherent L9981 cells cultured in serum-containing mediums, cells cultured in serum-free medium display sphere appearance. Doubling time of adherent cells and sphere cells are (56.05±1.95 h and (33.00±1.44 h respectively; Spheroid cells had higher invasion and tumorigenicity ability, 5 times and 20 times respectively, than adherent cells. Conclusion Suspension cultured L9981 in Serum-free medium could form spheroid populations. Cells in spheres had higher ability of invasion and Tumorigenicity than adherent L9981 cells. These results indicated spheroid L9981 cells contained enriched lung cancer stem cells, and Serum-free suspension culture can be a candidate method for enriching lung cancer stem cell.

  15. Proton exchange membrane fuel cells

    CERN Document Server

    Qi, Zhigang

    2013-01-01

    Preface Proton Exchange Membrane Fuel CellsFuel CellsTypes of Fuel CellsAdvantages of Fuel CellsProton Exchange Membrane Fuel CellsMembraneCatalystCatalyst LayerGas Diffusion MediumMicroporous LayerMembrane Electrode AssemblyPlateSingle CellStackSystemCell Voltage Monitoring Module (CVM)Fuel Supply Module (FSM)Air Supply Module (ASM)Exhaust Management Module (EMM)Heat Management Module (HMM)Water Management Module (WMM)Internal Power Supply Module (IPM)Power Conditioning Module (PCM)Communications Module (COM)Controls Module (CM)SummaryThermodynamics and KineticsTheoretical EfficiencyVoltagePo

  16. Cell-specific precursor processing

    DEFF Research Database (Denmark)

    Rehfeld, Jens F; Bundgaard, Jens R

    2010-01-01

    The singular gene for a peptide hormone is expressed not only in a specific endocrine cell type but also in other endocrine cells as well as in entirely different cells such as neurons, adipocytes, myocytes, immune cells, and cells of the sex-glands. The cellular expression pattern for each gene...... varies with development, time and species. Endocrine regulation is, however, based on the release of a given hormone from an endocrine cell to the general circulation from whose cappilaries the hormone reaches the specific target cell elsewhere in the body. The widespread expression of hormone genes in...... different cells and tissues therefore requires control of biogenesis and secretion in order to avoid interference with the function of a specific hormonal peptide from a particular endocrine cell. Several mechanisms are involved in such control, one of them being cell-specific processing of prohormones. The...

  17. Materials as stem cell regulators

    Science.gov (United States)

    Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

    2014-06-01

    The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine.

  18. Trophoblast lineage cells derived from human induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying, E-mail: ying.chen@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Wang, Kai; Chandramouli, Gadisetti V.R. [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Knott, Jason G. [Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University (United States); Leach, Richard, E-mail: Richard.leach@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Department of Obstetrics, Gynecology and Women’s Health, Spectrum Health Medical Group (United States)

    2013-07-12

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro.

  19. Trophoblast lineage cells derived from human induced pluripotent stem cells

    International Nuclear Information System (INIS)

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro

  20. Solid Oxide Electrolyser Cell

    DEFF Research Database (Denmark)

    Jensen, Søren Højgaard

    Solid oxide fuel cells (SOFCs) produced at Risø National Laboratory was tested as steam electrolysers under various current densities, operating temperatures and steam partial pressures. At 950 °C and a cell voltage of 1.48V the current density was -3.6A/cm2 with app. 30% H2 + 70% H2O in the inlet...... it is possible to achieve a production price of 0.7 US$/kg H2 with an electricity price of 1.3 US¢/kWh. The cell voltage was measured as function of time. In test ofabout two month of duration a long-term degradation was observed. At 850 °C, -0.5 A/cm2 with 50 vol% H2 the degradation rate was app. 20 mV/1000h...

  1. Fuel cell cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Wimer, J.G. [Dept. of Energy, Morgantown, WV (United States); Archer, D.

    1995-08-01

    The U.S. Department of Energy`s Morgantown Energy Technology Center (METC) sponsors the research and development of engineered systems which utilize domestic fuel supplies while achieving high standards of efficiency, economy, and environmental performance. Fuel cell systems are among the promising electric power generation systems that METC is currently developing. Buildings account for 36 percent of U.S. primary energy consumption. Cogeneration systems for commercial buildings represent an early market opportunity for fuel cells. Seventeen percent of all commercial buildings are office buildings, and large office buildings are projected to be one of the biggest, fastest-growing sectors in the commercial building cogeneration market. The main objective of this study is to explore the early market opportunity for fuel cells in large office buildings and determine the conditions in which they can compete with alternative systems. Some preliminary results and conclusions are presented, although the study is still in progress.

  2. Solar cell element

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko; Matsumoto, Hitoshi; Uda, Hiroshi; Komatsu, Yasumitsu; Ikegami, Kiyoharu.

    1989-05-18

    In the existing CdS/CdTe-based solar cell element, nothing is formed except the component effective for generating electromotive force and the components necessary for leading, collecting and extracting the generated electricity, hence even when the element shows deterioration of its performance during its usage, it has been difficult to analyze the above situation. In addition, it has also a defect that its characteristic such as the transfer efficiency in the neighborhood of its glass substrate in connection also with its manufacturing process. In order to solve the above problematical points, this invention proposes, with regard to a CdS-based solar cell element composed by forming a thin film on its substrate, to make a blank space on the above substrate and form thereon a thin film which composes the solar cell element concerned alone or in a piling up manner. 4 figs.

  3. ELECTROMOTIVE FORCE, EMF (CELLS)

    Energy Technology Data Exchange (ETDEWEB)

    Archer, M.D.; Feldberg, S.W.

    1998-09-16

    The voltage or electric potential difference across the terminals of a cell when no current is drawn from it. The emf of a cell is the sum of the electric potential differences (PDs) produced by a separation of charges (electrons or ions) that can occur at each phase boundary (or interface) in the cell. The magnitude of each PD depends on the chemical nature of the two contacting phases. Thus, at the interface between two different metals, some electrons will have moved from the metal with a higher free energy of electrons to the metal with a lower free energy of electrons. The resultant charge separation will produce a PD (just as charge separation produces a voltage across a capacitor) that, at equilibrium, exactly opposes further electron flow. Similarly, PDs can be produced when electrons partition across a metal/solution interface or metal/solid interface, and when ions partition across a solution/membrane/solution interface.

  4. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology (Finland). Dept. of Electrical and Communications Engineering

    1998-12-31

    Photovoltaic research began at the Electron Physics Laboratory of the Helsinki University of Tehnology in 1993, when the laboratory joined the national NEMO 2 research program. During the early stages of the photovoltaic research the main objective was to establish necessary measurement and characterisation routines, as well as to develop the fabrication process. The fabrication process development work has been supported by characterisation and theoretical modelling of the solar cells. Theoretical investigations have been concerned with systematic studies of solar cell parameters, such as diffusion lengths, surface recombination velocities and junction depths. The main result of the modelling and characterisation work is a method which is based on a Laplace transform of the so-called spatial collection efficiency function of the cell. The basic objective of the research has been to develop a fabrication process cheap enough to be suitable for commercial production

  5. Fuel cells in transportation

    Energy Technology Data Exchange (ETDEWEB)

    Erdmann, G. [Technische Univ., Berlin (Germany); Hoehlein, B. [Research Center Juelich (Germany)

    1996-12-01

    A promising new power source for electric drive systems is the fuel cell technology with hydrogen as energy input. The worldwide fuel cell development concentrates on basic research efforts aiming at improving this new technology and at developing applications that might reach market maturity in the very near future. Due to the progress achieved, the interest is now steadily turning to the development of overall systems such as demonstration plants for different purposes: electricity generation, drive systems for road vehicles, ships and railroads. This paper does not present results concerning the market potential of fuel cells in transportation but rather addresses some questions and reflections that are subject to further research of both engineers and economists. Some joint effort of this research will be conducted under the umbrella of the IEA Implementing Agreement 026 - Annex X, but there is a lot more to be done in this challenging but also promising fields. (EG) 18 refs.

  6. Welded solar cell interconnection

    Science.gov (United States)

    Stofel, E. J.; Browne, E. R.; Meese, R. A.; Vendura, G. J.

    1982-01-01

    The efficiency of the welding of solar-cell interconnects is compared with the efficiency of soldering such interconnects, and the cases in which welding may be superior are examined. Emphasis is placed on ultrasonic welding; attention is given to the solar-cell welding machine, the application of the welding process to different solar-cell configurations, producibility, and long-life performance of welded interconnects. Much of the present work has been directed toward providing increased confidence in the reliability of welding using conditions approximating those that would occur with large-scale array production. It is concluded that there is as yet insufficient data to determine which of three methods (soldering, parallel gap welding, and ultrasonic welding) provides the longest-duration solar panel life.

  7. Human leukaemic cells

    International Nuclear Information System (INIS)

    The results of the determination of trace elements in nucleic acids and histones in human leukaemic cells by activation analysis are reported. The Cr2+, Fe2+, Zn2+, Co2+ and Sb2+ content of DNA and RNA of leukaemic cells compared to that of lymphocytes from a patient with infectious mononucleosis or a normal donor are shown tabulated. Similar comparisons are shown for the same trace metal content of histones isolated from the same type of cells. It is felt that the results afford further interesting speculation that trace metals may be involved in the interactions between histones and DNA (especially at the binding sites of histones to DNA), which affect transcription characteristics. (U.K.)

  8. Stem cell therapy for diabetes

    OpenAIRE

    Lee, K. O.; Gan, S U; Calne, R Y

    2012-01-01

    Stem cell therapy holds immense promise for the treatment of patients with diabetes mellitus. Research on the ability of human embryonic stem cells to differentiate into islet cells has defined the developmental stages and transcription factors involved in this process. However, the clinical applications of human embryonic stem cells are limited by ethical concerns, as well as the potential for teratoma formation. As a consequence, alternative forms of stem cell therapies, such as induced plu...

  9. Radiosensitivity of mesothelioma cell lines

    International Nuclear Information System (INIS)

    The present study was carried out in order to examine the radiosensitivity of malignant pleural mesothelioma cell lines. Cell kinetics, radiation-induced delay of the cell cycle and DNA ploidy of the cell lines were also determined. For comparison an HeLa and a human foetal fibroblast cell line were simultaneously explored. Six previously cytogenetically and histologically characterized mesothelioma tumor cell lines were applied. A rapid tiazolyl blue microtiter (MTT) assay was used to analyze radiosensitivity and cell kinetics and DNA ploidy of the cultured cells were determined by flow cytometry. The survival fraction after a dose of 2 Gy (SF2), parameters α and β of the linear quadratic model (LQ-model) and mean inactivation dose (DMID) were also estimated. The DNA index of four cell lines equaled 1.0 and two cell lines equaled 1.5 and 1.6. Different mesothelioma cell lines showed a great variation in radiosensitivity. Mean survival fraction after a radiation dose of 2 Gy (SF2) was 0.60 and ranged from 0.36 to 0.81 and mean α value was 0.26 (range 0.48-0.083). The SF2 of the most sensitive diploid mesothelioma cell line was 0.36: Less than that of the foetal fibroblast cell line (0.49). The survival fractions (0.81 and 0.74) of the two most resistant cell lines, which also were aneuploid, were equal to that of the HeLa cell line (0.78). The α/β ratios of the most sensitive cell lines were almost an order of magnitude greater than those of the two most resistant cell lines. Radiation-induced delay of the most resistant aneuploid cell line was similar to that of HeLa cells but in the most sensitive (diploid cells) there was practically no entry into the G1 phase following the 2 Gy radiation dose during 36 h. (orig.)

  10. Stem cell organization in Arabidopsis

    OpenAIRE

    Wendrich, J.R.

    2016-01-01

    Growth of plant tissues and organs depends on continuous production of new cells, by niches of stem cells. Stem cells typically divide to give rise to one differentiating daughter and one non-differentiating daughter. This constant process of self-renewal ensures that the niches of stem cells or meristems stay active throughout plant-life. Specification of stem cells occurs very early during development of the emrbyo and they are maintained during later stages. The Arabidopsis embryo is a hig...

  11. Dense pattern optical multipass cell

    Science.gov (United States)

    Silver, Joel A [Santa Fe, NM

    2009-01-13

    A multiple pass optical cell and method comprising providing a pair of opposed cylindrical mirrors having curved axes with substantially equal focal lengths, positioning an entrance hole for introducing light into the cell and an exit hole for extracting light from the cell, wherein the entrance hole and exit hole are coextensive or non-coextensive, introducing light into the cell through the entrance hole, and extracting light from the cell through the exit hole.

  12. Characterization of cells in cork

    Science.gov (United States)

    Pina, P.; Fortes, M. A.

    1996-09-01

    Various topological and metric properties of the cells in the phelogen of the cork oak have been measured in tangential sections of cork by image analysis methods. These include the fractions 0022-3727/29/9/041/img5 of cells with i sides (i-cells), the fractions 0022-3727/29/9/041/img6 of adjacencies between i- and k-cells and various distributions of cell areas in relation to topology.

  13. NK cell-released exosomes

    OpenAIRE

    Fais, Stefano

    2013-01-01

    We have recently reported that human natural killer (NK) cells release exosomes that express both NK-cell markers and cytotoxic molecules. Similar results were obtained with circulating exosomes from human healthy donors. Both NK-cell derived and circulating exosomes exerted a full functional activity and killed both tumor and activated immune cells. These findings indicate that NK-cell derived exosomes might constitute a new promising therapeutic tool.

  14. Photoelectrochemical cell with nondissolving anode

    Science.gov (United States)

    Ellis, A. B.; Kaiser, S. W.; Wrighton, M. S.

    1980-01-01

    Improved electrolytic cells have efficiencies comparable to those of best silicon solar cells but are potentially less expensive to manufacture. Cells consist of light-sensitive n-type semiconductor anode and metallic cathode immersed in electrolytic solution. Reversible redox cells produce no chemical change in electrolyte and stabilize anode against dissolving. Cell can produce more than 500 mW of power per square centimeter of anode area at output voltage of 0.4 V.

  15. Interband Cascade Photovoltaic Cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Rui Q. [Univ. of Oklahoma, Norman, OK (United States); Santos, Michael B. [Univ. of Oklahoma, Norman, OK (United States); Johnson, Matthew B. [Univ. of Oklahoma, Norman, OK (United States)

    2014-09-24

    In this project, we are performing basic and applied research to systematically investigate our newly proposed interband cascade (IC) photovoltaic (PV) cells [1]. These cells follow from the great success of infrared IC lasers [2-3] that pioneered the use of quantum-engineered IC structures. This quantum-engineered approach will enable PV cells to efficiently convert infrared radiation from the sun or other heat source, to electricity. Such cells will have important applications for more efficient use of solar energy, waste-heat recovery, and power beaming in combination with mid-infrared lasers. The objectives of our investigations are to: achieve extensive understanding of the fundamental aspects of the proposed PV structures, develop the necessary knowledge for making such IC PV cells, and demonstrate prototype working PV cells. This research will focus on IC PV structures and their segments for utilizing infrared radiation with wavelengths from 2 to 5 μm, a range well suited for emission by heat sources (1,000-2,000 K) that are widely available from combustion systems. The long-term goal of this project is to push PV technology to longer wavelengths, allowing for relatively low-temperature thermal sources. Our investigations address material quality, electrical and optical properties, and their interplay for the different regions of an IC PV structure. The tasks involve: design, modeling and optimization of IC PV structures, molecular beam epitaxial growth of PV structures and relevant segments, material characterization, prototype device fabrication and testing. At the end of this program, we expect to generate new cutting-edge knowledge in the design and understanding of quantum-engineered semiconductor structures, and demonstrate the concepts for IC PV devices with high conversion efficiencies.

  16. The Stem Cell Conundrum

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ At the beginning of this year, Kelly Reynolds,a US-national diagnosed with amyotrophic lateral sclerosis (ALS), became the one of the latest overseas patient to undergo stem cell treatment at the Nanshan Hospital in Shenzhen.Confined to a wheelchair and with limited use of his hands,the 39-year old received four fetal stem cell injections over a three-week period. So far,the results have been positive and Reynolds, acording to his personal blog page, is upbeat about the long-term benefits.

  17. Optoelectronics of solar cells

    CERN Document Server

    Smestad, Greg P

    2002-01-01

    With concerns about worldwide environmental security, global warming, and climate change due to emissions of carbon dioxide from the burning of fossil fuels, it is desirable to have a wide range of energy technologies in a nation's portfolio. Photovoltaics, or solar cells, are a viable option as a nonpolluting renewable energy source. This text is designed to be an overview of photovoltaic solar cells for those in the fields of optics and optical engineering, as well as those who are interested in energy policy, economics, and the requirements for efficient photo-to-electric energy conversion.

  18. Rectenna solar cells

    CERN Document Server

    Moddel, Garret

    2013-01-01

    Rectenna Solar Cells discusses antenna-coupled diode solar cells, an emerging technology that has the potential to provide ultra-high efficiency, low-cost solar energy conversion. This book will provide an overview of solar rectennas, and provide thorough descriptions of the two main components: the diode, and the optical antenna. The editors discuss the science, design, modeling, and manufacturing of the antennas coupled with the diodes. The book will provide concepts to understanding the challenges, fabrication technologies, and materials required to develop rectenna structures. Written by e

  19. Silicon heterojunction solar cells

    CERN Document Server

    Fahrner, W R; Neitzert, H C

    2006-01-01

    The world of today must face up to two contradictory energy problems: on the one hand, there is the sharply growing consumer demand in countries such as China and India. On the other hand, natural resources are dwindling. Moreover, many of those countries which still possess substantial gas and oil supplies are politically unstable. As a result, renewable natural energy sources have received great attention. Among these, solar-cell technology is one of the most promising candidates. However, there still remains the problem of the manufacturing costs of such cells. Many attempts have been made

  20. Granular Cell Schwannoma

    Directory of Open Access Journals (Sweden)

    Dheepa R

    2004-01-01

    Full Text Available An 11 year old female child had a small painful spot over the scalp of 4 months duration. Earlier, she had undergone a local excision for a similar problem, but it had recurred at the same site after a few months. Examination revealed a skin colored sessile tender firm papule of 3 mm size on the right parietal region. Excision biopsy showed broad fascicles of tumor cells with eosinopilic cytoplasmic granules infiltrating the dermis amongst the collagen bundles, which was consistent with granular cell schwannoma.

  1. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Electrical and Communications Engineering

    1998-10-01

    Photovoltaic research in the Electron Physics Laboratory started in 1993, when laboratory joined the national TEKES/NEMO 2 research program. Since the beginning of the project, characterization as well as experimentally orientated development of the fabrication process of the solar cells were carried out parallery. The process development research started by the initiatives of the Finnish industry. At the moment a large amount of the laboratory personnel works on solar cell research and the financing comes mainly from external projects. The funding for the research has come from TEKES, Ministry of Education, Finnish Academy, GETA graduate school, special equipment grants of the university, and from the laboratory

  2. Clear cell chondrosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, R.; David, R.; Cierney, G. III

    1985-01-01

    The clinical, radiologic, and histopathologic features of three cases of clear cell chondrosarcoma are described. On radiographs, this rather benign-appearing tumor resembles a chondroblastoma when it occurs at the end of a long bone, and may occasionally show a calcified matrix. However, it has distinctive tumor cells with a centrally placed vesicular nucleus surrounded by clear cytoplasm. The lesion has a low-grade malignancy and is amenable to en bloc surgical resection, which results in a much better prognosis than that of conventional chondrosarcoma.

  3. Epidermal stem cell dynamics

    OpenAIRE

    Sieber-Blum, Maya

    2011-01-01

    Wong and Reiter have explored the possibility that hair follicle stem cells can give rise to basal cell carcinoma (BCC). They expressed in mice an inducible human BCC-derived oncogenic allele of Smoothened, SmoM2, under the control of either the cytokeratin 14 (K14) or cytokeratin 15 (K15) promoter. Smoothened encodes a G-protein-coupled receptor protein in the hedgehog pathway, the misregulation of which is implicated in BCC and other human cancers. Chronic injury is thought to be a contribu...

  4. Microfluidic Cell Culture Device

    Science.gov (United States)

    Takayama, Shuichi (Inventor); Cabrera, Lourdes Marcella (Inventor); Heo, Yun Seok (Inventor); Smith, Gary Daniel (Inventor)

    2014-01-01

    Microfluidic devices for cell culturing and methods for using the same are disclosed. One device includes a substrate and membrane. The substrate includes a reservoir in fluid communication with a passage. A bio-compatible fluid may be added to the reservoir and passage. The reservoir is configured to receive and retain at least a portion of a cell mass. The membrane acts as a barrier to evaporation of the bio-compatible fluid from the passage. A cover fluid may be added to cover the bio-compatible fluid to prevent evaporation of the bio-compatible fluid.

  5. Carbon Nanotube Solar Cells

    OpenAIRE

    Klinger, Colin; Patel, Yogeshwari; Postma, Henk W. Ch.

    2012-01-01

    We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabr...

  6. Fuel cell engineering

    CERN Document Server

    Sundmacher

    2012-01-01

    Fuel cells are attractive electrochemical energy converters featuring potentially very high thermodynamic efficiency factors. The focus of this volume of Advances in Chemical Engineering is on quantitative approaches, particularly based on chemical engineering principles, to analyze, control and optimize the steady state and dynamic behavior of low and high temperature fuel cells (PEMFC, DMFC, SOFC) to be applied in mobile and stationary systems. * Updates and informs the reader on the latest research findings using original reviews * Written by leading industry experts and scholars * Review

  7. Development of neural precursor cells from mouse embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    WU Xuan; LI Hai-di; Li Shu-nong; XU Hai-wei; XU Ling

    2001-01-01

    Objective: To explore the serum-free culture conditions for differentiating mouse embryonic stem cells (ES cells)into neural precursor cells (NPC) and compare the effects of human embryonic fibroblasts (HEF) as the feeder layer of ES with that of mouse embryonic fibroblasts (MEF)in vitro. Methods: Mouse ES cells were cultured in or not in feeder layer cells medium containing or not leukemia inhibitory factor to suppress their differentiation. Immunocytochemical method was used to identify NPC by detecting nestin antigen and alkaline phosphatase. Results: The ES cells cultured in HEF were positive to alkaline phosphatase. Serum-free medium allowed the differentiation of ES cells into NPC. Conclusion:HEF could replace MEF and keep the undifferentiated condition of ES cells with more benefits. NPC of high purity could be cultured from ES cells by serum-free culture method.

  8. Industrial n-type solar cells with >20% cell efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Romijn, I.G.; Anker, J.; Burgers, A.R.; Gutjahr, A.; Koppes, M.; Kossen, E.J.; Lamers, M.W.P.E.; Heurtault, Benoit; Saynova-Oosterling, D.S.; Tool, C.J.J. [ECN Solar Energy, Petten (Netherlands)

    2013-03-15

    To realize high efficiencies at low costs, ECN has developed the n-Pasha solar cell concept. The n-Pasha cell concept is a bifacial solar cell concept on n-Cz base material, with which average efficiencies of above 20% have been demonstrated. In this paper recent developments at ECN to improve the cost of ownership (lower Euro/Wp) of the n-Pasha cell concept are discussed. Two main drivers for the manufacturing costs of n-type solar cells are addressed: the n-type Cz silicon material and the silver consumption. We show that a large resistivity range between 2 and 8 cm can be tolerated for high cell efficiency, and that the costs due to the silver metallization can be significantly reduced while increasing the solar cell efficiency. Combining the improved efficiency and cost reduction makes the n-Pasha cell concept a very cost effective solution to manufacture high efficient solar cells and modules.

  9. Colorectal Cancer Stem Cells and Cell Death

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, Veronica [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Gaggianesi, Miriam [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Department of Cellular and Molecular Oncology, IRCCS Fondazione Salvatore Maugeri, Via Salvatore Maugeri, 27100 Pavia, PV (Italy); Spina, Valentina; Iovino, Flora [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Dieli, Francesco [Departement of Biopathology and Medicine Biotechnologies, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Stassi, Giorgio, E-mail: giorgio.stassi@unipa.it [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Department of Cellular and Molecular Oncology, IRCCS Fondazione Salvatore Maugeri, Via Salvatore Maugeri, 27100 Pavia, PV (Italy); Todaro, Matilde [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy)

    2011-04-11

    Nowadays it is reported that, similarly to other solid tumors, colorectal cancer is sustained by a rare subset of cancer stem–like cells (CSCs), which survive conventional anticancer treatments, thanks to efficient mechanisms allowing escape from apoptosis, triggering tumor recurrence. To improve patient outcomes, conventional anticancer therapies have to be replaced with specific approaches targeting CSCs. In this review we provide strong support that BMP4 is an innovative therapeutic approach to prevent colon cancer growth increasing differentiation markers expression and apoptosis. Recent data suggest that in colorectal CSCs, protection from apoptosis is achieved by interleukin-4 (IL-4) autocrine production through upregulation of antiapoptotic mediators, including survivin. Consequently, IL-4 neutralization could deregulate survivin expression and localization inducing chemosensitivity of the colon CSCs pool.

  10. Fuel Cell Testing - Degradation of Fuel Cells and its Impact on Fuel Cell Applications

    OpenAIRE

    Pfrang, Andreas

    2008-01-01

    Fuel cells are expected to play a major role in the future energy supply, especially polymer electrolyte membrane fuel cells could become an integral part in future cars. Reduction of degradation of fuel cell performance while keeping fuel cell cost under control is the key for an introduction into mass markets.

  11. Cell Cycle Related Differentiation of Bone Marrow Cells into Lung Cells

    Energy Technology Data Exchange (ETDEWEB)

    Dooner, Mark; Aliotta, Jason M.; Pimental, Jeffrey; Dooner, Gerri J.; Abedi, Mehrdad; Colvin, Gerald; Liu, Qin; Weier, Heinz-Ulli; Dooner, Mark S.; Quesenberry, Peter J.

    2007-12-31

    Green-fluorescent protein (GFP) labeled marrow cells transplanted into lethally irradiated mice can be detected in the lungs of transplanted mice and have been shown to express lung specific proteins while lacking the expression of hematopoietic markers. We have studied marrow cells induced to transit cell cycle by exposure to IL-3, IL-6, IL-11 and steel factor at different times of culture corresponding to different phases of cell cycle. We have found that marrow cells at the G1/S interface have a 3-fold increase in cells which assume a lung phenotype and that this increase is no longer seen in late S/G2. These cells have been characterized as GFP{sup +} CD45{sup -} and GFP{sup +} cytokeratin{sup +}. Thus marrow cells with the capacity to convert into cells with a lung phenotype after transplantation show a reversible increase with cytokine induced cell cycle transit. Previous studies have shown the phenotype of bone marrow stem cells fluctuates reversibly as these cells traverse cell cycle, leading to a continuum model of stem cell regulation. The present studies indicate that marrow stem cell production of nonhematopoietic cells also fluctuates on a continuum.

  12. Sertoli cells maintain Leydig cell number and peritubular myoid cell activity in the adult mouse testis.

    Directory of Open Access Journals (Sweden)

    Diane Rebourcet

    Full Text Available The Sertoli cells are critical regulators of testis differentiation and development. In the adult, however, their known function is restricted largely to maintenance of spermatogenesis. To determine whether the Sertoli cells regulate other aspects of adult testis biology we have used a novel transgenic mouse model in which Amh-Cre induces expression of the receptor for Diphtheria toxin (iDTR specifically within Sertoli cells. This causes controlled, cell-specific and acute ablation of the Sertoli cell population in the adult animal following Diphtheria toxin injection. Results show that Sertoli cell ablation leads to rapid loss of all germ cell populations. In addition, adult Leydig cell numbers decline by 75% with the remaining cells concentrated around the rete and in the sub-capsular region. In the absence of Sertoli cells, peritubular myoid cell activity is reduced but the cells retain an ability to exclude immune cells from the seminiferous tubules. These data demonstrate that, in addition to support of spermatogenesis, Sertoli cells are required in the adult testis both for retention of the normal adult Leydig cell population and for support of normal peritubular myoid cell function. This has implications for our understanding of male reproductive disorders and wider androgen-related conditions affecting male health.

  13. IARS2 silencing induces non-small cell lung cancer cells proliferation inhibition, cell cycle arrest and promotes cell apoptosis.

    Science.gov (United States)

    Yin, J; Liu, W; Li, R; Liu, J; Zhang, Y; Tang, W; Wang, K

    2016-01-01

    The purpose of this study was to investigate the potential role of Ileucyl-tRNA synthetase (IARS2) silencing in non-small cell lung cancer (NSCLC). The silencing of IARS2 in H1299 cells and A549 cells were performed by lentivirus encoding shRNAs. The efficiency of IARS2 silencing was detected by quantitative real time PCR and western blot. The effects of IARS2 silencing on cell growth, cell apoptosis, cell cycle and cell colony formation ability were assessed by cells counting, MTT assay, flow cytometer analysis and soft agar colony formation assay, respectively. Compared with negative control group, IARS2 was significantly knockdown by transfection with lentivirus encoding shRNA of IARS2. The IARS2 silencing significantly inhibited the cells proliferation and cells colony formation ability, induced cell cycle arrest at G1/S phase and promoted cell apoptosis. IARS2 silencing induced NSCLC cells growth inhibition, cell cycle arrest and promoted cell apoptosis. These results suggest that IARS2 may be a novel target for the treatment of NSCLC. PMID:26639235

  14. Improved micromorph tandem cell performance through enhanced top cell currents

    Energy Technology Data Exchange (ETDEWEB)

    Platz, R.; Vaucher, N.P.; Fischer, D.; Meier, J.; Shah, A. [Univ. de Neuchatel (Switzerland). Inst. de Microtechnique

    1997-12-31

    Two approaches to increasing the current in the amorphous silicon top cell of an amorphous silicon/microcrystalline silicon (a-Si:H/{micro}c-Si:H) tandem cell are presented. The goal is to raise the stabilized efficiency of such cells. The deposition of the amorphous top cell at higher than standard substrate temperature is shown to reduce the optical gap of the i-layer and to increase the current which is generated with a given i-layer thickness. Furthermore, a selectively reflecting ZnO interface layer between the component cells is presented as a viable tool for enhancing the current generation in the top cell by selective reflection of light. The authors present a micromorph tandem cell containing the amorphous top cell deposited at high substrate temperature, and additionally the ZnO mirror layer. A top cell thickness of 150 nm is shown to be sufficient to provide a current density of 13mA/cm{sup 2} in the top cell. Finally, the influence of such thin top cells on the stabilized efficiency of the tandem cell is investigated by experiment and by means of semi-empirical modeling. Model and experiment confirm that such reduced-gap top cells, together with current enhancement due to the mirror layer, have a high potential for improving the stabilized efficiency of micromorph tandem cells.

  15. Adult Pancreatic Alpha-Cells: A New Source of Cells for Beta-Cell Regeneration

    OpenAIRE

    Chung, Cheng-Ho; Levine, Fred

    2010-01-01

    Beta-cell deficit is the major pathological feature in type 1 and type 2 diabetes patients, and plays a key role in disease progression. In principle, beta-cell regeneration can occur by replication of pre-existing beta-cells, or by beta-cell neogenesis from stem/progenitors. Unfortunately, beta-cell replication is limited by the almost complete absence of beta-cells in patients with type 1 diabetes, and the increasing recognition that the beta-cell replicative capacity declines severely with...

  16. How Is Sickle Cell Disease Treated?

    Science.gov (United States)

    ... sickle cell disease, go to the Health Topics Sickle Cell Anemia article. Living With and Managing Sickle Cell Disease ( ... the most severe form of sickle cell disease, sickle cell anemia, Tiffany has lived with the symptoms and complications ...

  17. How Is Sickle Cell Disease Diagnosed?

    Science.gov (United States)

    ... sickle cell disease, go to the Health Topics Sickle Cell Anemia article. Living With and Managing Sickle Cell Disease ( ... the most severe form of sickle cell disease, sickle cell anemia, Tiffany has lived with the symptoms and complications ...

  18. Laser biomodulation on stem cells

    Science.gov (United States)

    Liu, Timon C.; Duan, Rui; Li, Yan; Li, Xue-Feng; Tan, Li-Ling; Liu, Songhao

    2001-08-01

    Stem cells are views from the perspectives of their function, evolution, development, and cause. Counterintuitively, most stem cells may arise late in development, to act principally in tissue renewal, thus ensuring an organisms long-term survival. Surprisingly, recent reports suggest that tissue-specific adult stem cells have the potential to contribute to replenishment of multiple adult tissues. Stem cells are currently in the news for two reasons: the successful cultivation of human embryonic stem cell lines and reports that adult stem cells can differentiate into developmentally unrelated cell types, such as nerve cells into blood cells. The spotlight on stem cells has revealed gaps in our knowledge that must be filled if we are to take advantage of their full potential for treating devastating degenerative diseases such as Parkinsons's disease and muscular dystrophy. We need to know more about the intrinsic controls that keep stem cells as stem cells or direct them along particular differentiation pathways. Such intrinsic regulators are, in turn, sensitive to the influences of the microenvironment, or niche, where stem cells normally reside. Both intrinsic and extrinsic signals regular stem cell fate and some of these signals have now been identified. Vacek et al and Wang et al have studied the effect of low intensity laser on the haemopoietic stem cells in vitro. There experiments show there is indeed the effect of low intensity laser on the haemopoietic stem cells in vitro, and the present effect is the promotion of haemopoietic stem cells proliferation. In other words, low intensity laser irradiation can act as an extrinsic signal regulating stem cell fate. In this paper, we study how low intensity laser can be used to regulate stem cell fate from the viewpoint of collective phototransduction.

  19. Development of PEM fuel cell technology at international fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, D.J.

    1996-04-01

    The PEM technology has not developed to the level of phosphoric acid fuel cells. Several factors have held the technology development back such as high membrane cost, sensitivity of PEM fuel cells to low level of carbon monoxide impurities, the requirement to maintain full humidification of the cell, and the need to pressurize the fuel cell in order to achieve the performance targets. International Fuel Cells has identified a hydrogen fueled PEM fuel cell concept that leverages recent research advances to overcome major economic and technical obstacles.

  20. Enrichment and Function Research of Large Cell Lung Cancer Stem Cell-like Cells

    OpenAIRE

    Wenke YUE; JIAO, FENG; Liu, Bin; Jiacong YOU; Zhou, Qinghua

    2011-01-01

    Background and objective There are no universal method to recognize and screen for lung cancer stem cell markers and indicators. Commonly used methods are flow Cytometry and learning from other cancer stem cell sorting tags to sort lung cancer stem cells. But this method has low specificity screening, the workload is huge. In this study, Serum-free suspension culture was used to enrich lung cancer stem cells, and explore method for lung cancer stem cell screening. Methods Human large lung can...

  1. NASA Facts, Solar Cells.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    The design and function of solar cells as a source of electrical power for unmanned space vehicles is described in this pamphlet written for high school physical science students. The pamphlet is one of the NASA Facts Science Series (each of which consists of four pages) and is designed to fit in the standard size three-ring notebook. Review…

  2. Cell lines and Salmonella

    NARCIS (Netherlands)

    Jonge R de; Hendriks H; Garssen J; Universteit Utrecht, afdeling; MGB; LPI

    2001-01-01

    In human gastrointestinal disease caused by Salmonella, transepithelial migration of neutrophils follows the attachment of bacteria to epithelial tissue. This migration of neutrophils is stimulated by the release of chemokines, including interleukin-8 (Il -8), from the epithelial cells. We have dev

  3. Silky gels for cells

    NARCIS (Netherlands)

    Wlodarczyk, M.K.

    2016-01-01

    Tissue engineering is a relatively new, but actively developing field of biomedical science. It aims at organ or tissue regeneration by use of scaffolds, which are usually seeded with cells prior to implantation, and stimulated by bioactive cues or growth factors. It is a promising and valuable alte

  4. Basal Cell Carcinoma

    Science.gov (United States)

    ... resources Meet our partners Español Donate Diseases and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases ... cell carcinoma public SPOT Skin Cancer™ Diseases and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases ...

  5. Squamous Cell Carcinoma

    Science.gov (United States)

    ... resources Meet our partners Español Donate Diseases and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases ... cell carcinoma public SPOT Skin Cancer™ Diseases and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases ...

  6. Solid Oxide Fuel Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The solid oxide fuel cell comprising a metallic support material, an active anode layer consisting of a good hydrocarbon cracking catalyst, an electrolyte layer, an active cathode layer, and a transition layer consisting of preferably a mixture of LSM and a ferrite to the cathode current collector...

  7. Goblet cell carcinoids

    DEFF Research Database (Denmark)

    Olsen, Ingrid Holst; Holt, Nanna; Langer, Seppo W;

    2015-01-01

    BACKGROUND: Appendiceal goblet cell carcinoids (GCCs) exhibit neuroendocrine and adenocarcinoma features. PATIENTS AND METHODS: Analysis of demography, pathology, prognostic markers, treatment and survival in 83 GCC patients (f/m: 56/27) diagnosed 1992-2013. RESULTS: Median age for f/m was 59...

  8. Mechanical shielded hot cell

    International Nuclear Information System (INIS)

    A plan to erect a mechanical shielded hot cell in the process hall of the Radiochemical Laboratory at Inchas is described. The hot cell is designed for safe handling of spent fuel bundles, from the Inchas reactor, and for dismantling and cutting the fuel rods in preparation for subsequent treatment. The biological shielding allows for the safe handling of a total radioactivity level up to 10,000 MeV-Ci. The hot cell consists of an α-tight stainless-steel box, connected to a γ-shielded SAS, through an air-lock containing a movable carriage. The α-box is tightly connected with six dry-storage cavities for adequate storage of the spent fuel bundles. Both the α-box, with the dry-storage cavities, and the SAS are surrounded by 200-mm thick biological lead shielding. The α-box is equipped with two master-slave manipulators, a lead-glass window, a monorail crane and Padirac and Minirag systems. The SAS is equipped with a lead-glass window, tong manipulator, a shielded pit and a mechanism for the entry of the spent fuel bundle. The hot cell is served by adequate ventilation and monitoring systems. (author)

  9. Sickle Cell Anemia Bibliography.

    Science.gov (United States)

    Christy, Steven C.

    Presents sources for the acquisition of medical, social, psychological, educational, and practical knowledge of sickle cell anemia. The materials listed are designed to help parents, educators, and public service workers. Materials include journal articles, films, brochures, slides, and fact sheets. The usual bibliographic information is given.…

  10. Cell Phones for Science

    Science.gov (United States)

    Lucking, Robert A.; Christmann, Edwin P.; Wighting, Mervyn J.

    2010-01-01

    Although in some schools cell phones have to be turned off or perhaps kept in lockers to avoid misuse, the authors hope to demonstrate in this article how they can be used under supervision to assist learning. This ubiquitous device can be a powerful classroom tool. (Contains 2 figures.)

  11. Cell Phone RF Radiation

    Science.gov (United States)

    Abdul-Razzaq, Wathiq

    2015-01-01

    In a recent article in "Physics Today," Meredith and Redish emphasized the need to make introductory physics courses beneficial for life sciences majors. In this study, a lab activity is proposed to measure the intensity of electromagnetic waves emitted by cell phones and connect these measurements to various standards, biological…

  12. T cell traffic signals

    OpenAIRE

    Van Epps, Heather L.

    2005-01-01

    In 1990, Charles Mackay and colleagues combined classical physiology with modern molecular biology to provide the first concrete evidence that naive and memory T cells follow distinct migratory routes out of the bloodstream— a discovery that helped invigorate the field of lymphocyte homing.

  13. Pulmonary Langerhans cell Histiocytosis.

    Science.gov (United States)

    Harari, S; Comel, A

    2001-10-01

    Pulmonary Langerhans cell Histiocytosis is a rare granulomatous disease affecting both sexes, with greater incidence in the second and third decades of life; smoking appears to be the most important risk factor. Its etiology is unknown, although there are data indicating an uncontrolled immune response as possible cause, sustained by the Langerhans cells, antigen presenting cells for T lymphocytes, and their accumulation in the distal bronchioles; these cells express on their surface the CD1a and CD1c antigens, and the B7 molecule, essential for activating quiescent T lymphocytes. In its evolution the granuloma is characterized by the progressive reduction in the LC number, with the increase of fibrosis, surrounding and destroying the bronchiolar lumen; the remaining of the lumen, or the traction exerted by fibrous tissue on the adjacent alveolar spaces leads to the cyst development. Vascular involvement occurs frequently, and may explain the onset of pulmonary hypertension in advanced cases of the disease. The disease may be asymptomatic, or it may present with aspecific respiratory signs and symptoms, and has characteristic radiological findings, being included in the group of cysticaerial parenchymal alterations. The diagnosis could be suggested by the finding of a number of LC in BAL greater than 5%. Different therapies have been proposed, but it seems that the most important measure is smoking cessation. PMID:11587096

  14. Mammalian cell biology

    International Nuclear Information System (INIS)

    Progress is reported on studies of the molecular biology and functional changes in cultured mammalian cells following exposure to x radiation, uv radiation, fission neutrons, or various chemical environmental pollutants alone or in combinations. Emphasis was placed on the separate and combined effects of polycyclic aromatic hydrocarbons released during combustion of fossil fuels and ionizing and nonionizing radiations. Sun lamps, which emit a continuous spectrum of near ultraviolet light of 290 nm to 315 nm were used for studies of predictive cell killing due to sunlight. Results showed that exposure to uv light (254 nm) may not be adequate to predict effects produced by sunlight. Data are included from studies on single-strand breaks and repair in DNA of cultured hamster cells exposed to uv or nearultraviolet light. The possible interactions of the polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)-anthracene (DmBA) alone or combined with exposure to x radiation, uv radiation (254 nm) or near ultraviolet simulating sunlight were compared for effects on cell survival

  15. Fibronectin-cell interactions

    DEFF Research Database (Denmark)

    Couchman, J R; Austria, M R; Woods, A

    1990-01-01

    Fibronectins are widespread extracellular matrix and body fluid glycoproteins, capable of multiple interactions with cell surfaces and other matrix components. Their structure at a molecular level has been resolved, yet there are still many unanswered questions regarding their biologic activity i...

  16. The intestinal stem cell.

    NARCIS (Netherlands)

    Barker, N.; van de Wetering, M.L.; Clevers, H.

    2008-01-01

    The epithelium of the adult mammalian intestine is in a constant dialog with its underlying mesenchyme to direct progenitor proliferation, lineage commitment, terminal differentiation, and, ultimately, cell death. The epithelium is shaped into spatially distinct compartments that are dedicated to ea

  17. Urothelial Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Irena Dimov

    2010-01-01

    Full Text Available There is mounting evidence supporting the idea that tumors, similar to normal adult tissues, arise from a specific stem-like cell population, the cancer stem cells (CSCs, which are considered as the real driving force behind tumor growth, the ability to metastasize, as well as resistance to conventional antitumor therapy. The concept that cancer growth recapitulates normal proliferative and/or regenerative processes, even though in very dysfunctional ways, has tremendous implications for cancer therapy. The rapid development of the CSC field, shoulder to shoulder with powerful genome-wide screening techniques, has provided cause for optimism for the development of more reliable therapies in the future. However, several important issues still lie ahead. Recent identification of a highly tumorigenic stem-like compartment and existence of urothelial differentiation programs in urothelial cell carcinomas (UCCs raised important questions about UCC initiation and development. This review examines the present knowledge on CSCs in UCCs regarding the similarities between CSCs and the adult urothelial stem cells, potential origin of urothelial CSCs, main regulatory pathways, surface markers expression, and the current state of CSC-targeting therapeutic strategies.

  18. The Plant Cell Surface

    Institute of Scientific and Technical Information of China (English)

    Anne-Mie C.Emons; Kurt V.Fagerstedt

    2010-01-01

    @@ Multicellular organization and tissue construction has evolved along essentially different lines in plants and animals. Since plants do not run away, but are anchored in the soil, their tissues are more or less firm and stiff. This strength stems from the cell walls, which encase the fragile cytoplasm, and protect it.

  19. Engineering stem cell niches in bioreactors

    OpenAIRE

    2013-01-01

    Stem cells, including embryonic stem cells, induced pluripotent stem cells, mesenchymal stem cells and amniotic fluid stem cells have the potential to be expanded and differentiated into various cell types in the body. Efficient differentiation of stem cells with the desired tissue-specific function is critical for stem cell-based cell therapy, tissue engineering, drug discovery and disease modeling. Bioreactors provide a great platform to regulate the stem cell microenvironment, known as “ni...

  20. Stem Cells and Tissue Engineering

    CERN Document Server

    Pavlovic, Mirjana

    2013-01-01

    Stem cells are the building blocks for all other cells in an organism. The human body has about 200 different types of cells and any of those cells can be produced by a stem cell. This fact emphasizes the significance of stem cells in transplantational medicine, regenerative therapy and bioengineering. Whether embryonic or adult, these cells can be used for the successful treatment of a wide range of diseases that were not treatable before, such as osteogenesis imperfecta in children, different forms of leukemias, acute myocardial infarction, some neural damages and diseases, etc. Bioengineering, e.g. successful manipulation of these cells with multipotential capacity of differentiation toward appropriate patterns and precise quantity, are the prerequisites for successful outcome and treatment. By combining in vivo and in vitro techniques, it is now possible to manage the wide spectrum of tissue damages and organ diseases. Although the stem-cell therapy is not a response to all the questions, it provides more...