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Sample records for activated recombinative desorption

  1. ACTIVATION ENERGY OF DESORPTION OF DIBENZOFURAN ON ACTIVATED CARBONS

    Institute of Scientific and Technical Information of China (English)

    LI Xiang; LI Zhong; XI Hongxia; LUO Lingai

    2004-01-01

    Three kinds of commercial activated carbons, such as Norit RB1, Monolith and Chemviron activated carbons, were used as adsorbents for adsorption of dibenzofuran. The average pore size and specific surface area of these activated carbons were measured. Temperature Programmed Desorption (TPD) experiments were conducted to measure the TPD curves of dibenzofuran on the activated carbons, and then the activation energy for desorption of dibenzofuran on the activated carbons was estimated. The results showed that the Chemviron and the Norit RB1 activated carbon maintained higher specific surface area and larger micropore pore volume in comparison with the Monolith activated carbon, and the activation energy for the desorption of dibenzofuran on these two activated carbons was higher than that on the Monolith activated carbon. The smaller the pore of the activated carbon was, the higher the activated energy of dibenzofuran desorption was.

  2. Recombinant snake venom prothrombin activators

    OpenAIRE

    Lövgren, Ann

    2012-01-01

    Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need ...

  3. Recombinant snake venom prothrombin activators.

    Science.gov (United States)

    Lövgren, Ann

    2013-01-01

    Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need for additional cofactors, but does not discriminate non-carboxylated prothrombin from biologically active γ-carboxylated prothrombin. Here we report that recombinant trocarin and oscutarin could not efficiently generate thrombin without additional protein co-factors. We confirm that both trocarin and oscutarin are similar to human coagulation Factor X (FX), explaining the need for additional cofactors. Sequencing of a genomic fragment containing 7 out of the 8 exons coding for oscutarin further confirmed the similarity to human FX. PMID:23111318

  4. ESTIMATION OF ACTIVATED ENERGY OF DESORPTION OF n—HEXANE ON ACTIVATED CARBONS BY PTD TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    LIZhong; WANGHongjuan; 等

    2001-01-01

    In this paper,six kinds of activated carbons such as Ag+-activated carbon,Cu2+activated carbon,Fe3+-activated carbon,activated carbon,Ba2+-activated carbon and Ca2+activated carbon were prepared.The model for estimating activated energy of desorption was established.Temperature-programmed desorption(TPD)experiments were conducted to measure the TPD curves of n-hexanol and then estimate the activation energy for desorption of n-hexanol on the activated carbons.Results showed that the activation energy for the desorption of n-hexanol on the Ag+-activated carbon,the Cu2+-activated carbon and the Fe3+-activated carbon were higher than those of n-hexanol on the activated carbon,the Ca2+-activated carbon and the Ba2+-activated carbon.

  5. ESTIMATION OF ACTIVATED ENERGY OF DESORPTION OF n-HEXANE ON ACTIVATED CARBONS BY TPD TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this paper, six kinds of activated carbons such as Ag+-activated carbon, Cu2+-activated carbon, Fe3+- activated carbon, activated carbon, Ba2+- activated carbon and Ca2+-activated carbon were prepared. The model for estimating activated energy of desorption was established. Temperature-programmed desorption (TPD) experiments were conducted to measure the TPD curves of n-hexanol and then estimate the activation energy for desorption of n-hexanol on the activated carbons. Results showed that the activation energy for the desorption of n-hexanol on the Ag+- activated carbon, the Cu2+- activated carbon and the Fe3+- activated carbon were higher than those of n-hexanol on the activated carbon, the Ca2+- activated carbon and the Ba2+- activated carbon.

  6. Magnetic monitoring of the hydrogenation-decomposition-desorption-recombination process in SmFe-based alloys

    International Nuclear Information System (INIS)

    A clear understanding of the reactions and phase changes that occur during the processing of a material is vital if we want to be able to achieve the best properties. In this series of experiments, we have used a vibrating-sample magnetometer (VSM) to monitor the magnetic state of compacted powder samples of Sm13.7Fe86.3 and Sm13.8Fe82.2Ta4.0 during a standard hydrogenation-disproportionation-desorption-recombination (HDDR) cycle. The samples were mounted in the VSM and heated at 4 deg.C/min in 1 bar of flowing hydrogen to 750 deg.C, they were then held for 60 min under hydrogen and approximately 120 min under vacuum before being cooled to room temperature under vacuum at 4 deg.C/min. The results show that the initial absorption of hydrogen by the Sm2Fe17-type phase results in an increase in magnetization as well as TC. At higher temperatures, the disproportionation reactions of the Sm13.7Fe86.3 and Sm13.8Fe82.2Ta4.0 materials were observed to proceed at a faster rate for the second and third cycles of the HDDR procedure than for the first. The results are in agreement with our previous transmission electron microscopy studies, which showed that much of the Ta that was initially dissolved in the Sm2Fe17-type phase of the cast Sm13.8Fe82.2Ta4.0 material was reformed as Ta-based precipitates after a single HDDR cycle leaving the Sm2Fe17-type phase with much less dissolved Ta

  7. The development of microstructure during hydrogenation-disproportionation-desorption-recombination treatment of sintered neodymium-iron-boron-type magnets

    Science.gov (United States)

    Sheridan, R. S.; Harris, I. R.; Walton, A.

    2016-03-01

    The hydrogen absorption and desorption characteristics of the hydrogenation disproportionation desorption and recombination (HDDR) process on scrap sintered neodymium-iron-boron (NdFeB) type magnets have been investigated. At each stage of the process, the microstructural changes have been studied using high resolution scanning electron microscopy. It was found that the disproportionation reaction initiates at grain boundaries and triple points and then propagates towards the centre of the matrix grains. This process was accelerated at particle surfaces and at free surfaces produced by any cracks in the powder particles. However, the recombination reaction appeared to initiate randomly throughout the particles with no apparent preference for particle surfaces or internal cracks. During the hydrogenation of the grain boundaries and triple junctions, the disproportionation reaction was, however, affected by the much higher oxygen content of the sintered NdFeB compared with that of the as-cast NdFeB alloys. Throughout the entire HDDR reaction the oxidised triple junctions (from the sintered structure) remained unreacted and hence, remained in their original form in the fine recombined microstructure. This resulted in a very significant reduction in the proportion of cavitation in the final microstructure and this could lend to improved consolidation in the recycled magnets.

  8. Nd sub 2 Fe sub 1 sub 4 C processed by the hydrogenation, disproportionation, desorption and recombination (HDDR) process

    CERN Document Server

    Sui, Y C; Liu, W; Xiao, Q F; Zhao, X G; Zhao, T; Chuang, Y C

    1998-01-01

    The hydrogenation, disproportionation, desorption and recombination (HDDR) process has been employed to produce Nd sub 2 Fe sub 1 sub 4 C-based permanent magnets. The master alloys for HDDR are Nd sub 2 Fe sub 1 sub 4 C-based alloys which are obtained by annealing mechanically alloyed (MA) Nd sub 1 sub 6 Fe sub 7 sub 5 C sub 9 powder at 850 deg. C. The disproportionation reaction at 850 deg. C results in the formation of an intimate mixture of Nd-hydride, alpha-Fe and Nd sub 2 Fe sub 2 C sub 3. On desorbing the hydrogen at the same temperature, different constituents recombine to form the thermodynamically stable Nd sub 2 Fe sub 1 sub 4 C and the Nd-rich phase, depending sensitively on recombination time and slightly on hydrogenation time. The phases obtained by HDDR at 950 deg. C consist of Nd sub 2 Fe sub 1 sub 7 C sub x , alpha-Fe, the Nd-rich phase and Nd sub 2 C sub 3 , whereas those obtained at 700 deg. C are of Nd sub 2 Fe sub 1 sub 7 C sub x , the Nd-rich phase and a small amount of alpha-Fe. For comp...

  9. Desorption of uranium from titanium-activated carbon composite adsorbent with acidic eluent, (1)

    International Nuclear Information System (INIS)

    An investigation was carried out on the desorption of uranium from titanium-activated carbon composite adsorbent with acidic eluent by the batch process. The rate of desorption of uranium with acidic eluent depended on temperature, showing an increase as the temperature was raised. But the rate of desorption with acidic eluent was less dependent on temperature than that obtained when mixed eluent of sodium carbonate-sodium hydrogencarbonate was used. The difference of the rate of desorption of uranium in the range of concentration from 0.3 to 0.5N was not found, and the rate of desorption with sulfuric acid was slightly higher than that obtained when hydrochloric acid was used. The amount of dissolved titanium decreased as the ratio of adsorbent to eluent (RAE) was increased. At RAE of 10%, the percentage of dissolved titanium (DTI) was below 0.38% with sulfuric acid, below 0.7% with hydrochloric acid. These values were found to be higher than the ones with the carbonate eluent. The elements except uranium, which were adsorbed on the adsorbent, were eluted simultaneously with acidic eluent. The regeneration of the adsorbent after desorption, therefore, was found to be unnecessary. In a repeated test of adsorption-desorption treatment up to five times, the percentage of uranium adsorbed from natural sea water was approximately constant of 85%. From these results, the application of column process to the desorption of uranium with acidic eluent at room temperature was proposed to be feasible. (author)

  10. Effect Of The Desorption-Recombination Temperature On The Microstructure And Magnetic Properties Of HDDR Processed Nd-Fe-B Powders

    Directory of Open Access Journals (Sweden)

    Lee J.-G.

    2015-06-01

    Full Text Available The effect of the desorption-recombination temperature on the microstructure and magnetic properties of hydrogenation-disproportionation-desorption-recombination (HDDR processed Nd-Fe-B powders was studied. The NdxB6.4Ga0.3Nb0.2Febal (x=12.5-13.5, at.% casting alloys were pulverized after homogenizing annealing, and then subjected to HDDR treatment. During the HDDR process, desorption-recombination (DR reaction was induced at two different temperature, 810°C and 820°C. The higher Nd content resulted in enhanced coercivity of the HDDR powder, and which was attributed to the thicker and more uniform Nd-rich phase along grain boundaries. But this uniform Nd-rich phase induced faster grain growth. The remanence of the powder DR-treated at 820°C is higher than that DR-treated at 810°C. In addition, it was also confirmed that higher DR temperature is much more effective to improve squareness.

  11. Effect of soil type on adsorption-desorption, mobility, and activity of the herbicide norflurazon

    OpenAIRE

    Morillo González, Esmeralda; Undabeytia López, Tomás; Cabrera Mesa, Alegría; Villaverde Capellán, J.; Maqueda Porras, Celia

    2004-01-01

    Adsorption-desorption studies of norflurazon on 17 soils of very different characteristics have been performed using a batch equilibration method and correlated to its mobility, activity, and persistence in soils. The influence of different soil properties and components on norflurazon adsorption was determined. The significant variables were organic matter (OM) content and iron and aluminum oxides, which accounted for 85 and 11% of the variability, respectively. Norflurazon desorption from s...

  12. Electrothermal adsorption and desorption of volatile organic compounds on activated carbon fiber cloth.

    Science.gov (United States)

    Son, H K; Sivakumar, S; Rood, M J; Kim, B J

    2016-01-15

    Adsorption is an effective means to selectively remove volatile organic compounds (VOCs) from industrial gas streams and is particularly of use for gas streams that exhibit highly variable daily concentrations of VOCs. Adsorption of such gas streams by activated carbon fiber cloths (ACFCs) and subsequent controlled desorption can provide gas streams of well-defined concentration that can then be more efficiently treated by biofiltration than streams exhibiting large variability in concentration. In this study, we passed VOC-containing gas through an ACFC vessel for adsorption and then desorption in a concentration-controlled manner via electrothermal heating. Set-point concentrations (40-900 ppm(v)) and superficial gas velocity (6.3-9.9 m/s) were controlled by a data acquisition and control system. The results of the average VOC desorption, desorption factor and VOC in-and-out ratio were calculated and compared for various gas set-point concentrations and superficial gas velocities. Our results reveal that desorption is strongly dependent on the set-point concentration and that the VOC desorption rate can be successfully equalized and controlled via an electrothermal adsorption system.

  13. Electrospray ionization and matrix assisted laser desorption/ionization mass spectrometry: powerful analytical tools in recombinant protein chemistry

    DEFF Research Database (Denmark)

    Andersen, Jens S.; Svensson, B; Roepstorff, P

    1996-01-01

    Electrospray ionization and matrix assisted laser desorption/ionization are effective ionization methods for mass spectrometry of biomolecules. Here we describe the capabilities of these methods for peptide and protein characterization in biotechnology. An integrated analytical strategy is presen......Electrospray ionization and matrix assisted laser desorption/ionization are effective ionization methods for mass spectrometry of biomolecules. Here we describe the capabilities of these methods for peptide and protein characterization in biotechnology. An integrated analytical strategy...

  14. Effect of textural property of coconut shell-based activated carbon on desorption activation energy of benzothiophene

    Institute of Scientific and Technical Information of China (English)

    Moxin YU; Zhong LI; Hongxia XI; Qibin XIA; Shuwen WANG

    2008-01-01

    In this work,the effect of the textural property of activated carbons on desorption activation energy and adsorption capacity for benzothiophene (BT) was investi-gated.BET surface areas and the textural parameters of three kinds of the activated carbons,namely SY-6,SY-13 and SY-19,were measured with an ASAP 2010 instru-ment.The desorption activation energies of BT on the activated carbons were determined by temperature-pro-grammed desorption (TPD).Static adsorption experi-ments were carried out to determine the isotherms of BT on the activated carbons.The influence of the textural property of the activated carbons on desorption activa-tion energy and the adsorption capacity for BT was dis-cussed.Results showed that the BET surface areas of the activated carbons,SY-6,SY-13 and SY-19 were 1106,diameters were 1.96,2.58 and 2.16 nm,respectively.The TPD results indicated that the desorption activation energy of BT on the activated carbons,SY-6,SY-19 and SY-13 were 58.84,53.02 and 42.57 KJ/mol,respectively.The isotherms showed that the amount of BT adsorbed on the activated carbons followed the order of SY-6 > SY-19 > SY-13.The smaller the average pore diameter of the activated carbon,the stronger its adsorption for BT and the higher the activation energy required for BT desorp-tion on its surface.The Freundlich adsorption isotherm model can be properly used to formulate the adsorption behavior of BT on the activated carbons.

  15. Impact of activated carbon, biochar and compost on the desorption and mineralization of phenanthrene in soil

    DEFF Research Database (Denmark)

    Marchal, Geoffrey; Smith, Kilian E.C.; Rein, Arno;

    2013-01-01

    amounts mineralized were 28% for the unamended control, 19% for compost, 13% for biochar and 4% for AC. Therefore, the effects of the amendments in soil in reducing desorption were also reflected in the extents of mineralization. Modeling was used to analyze key processes, indicating that for the AC......Sorption of PAHs to carbonaceous soil amendments reduces their dissolved concentrations, limiting toxicity but also potentially biodegradation. Therefore, the maximum abiotic desorption of freshly sorbed phenanthrene (≤5 mg kg−1) was measured in three soils amended with activated carbon (AC......), biochar or compost. Total amounts of phenanthrene desorbed were similar between the different soils, but the amendment type had a large influence. Complete desorption was observed in the unamended and compost amended soils, but this reduced for biochar (41% desorbed) and AC (8% desorbed). Cumulative...

  16. Helium Retention and Desorption Behaviour of Reduced Activation Ferritic/Martenstic Steel

    Science.gov (United States)

    Wang, Pinghuai; Nobuta, Yuji; Hino, Tomoaki; Yamauchi, Yuji; Chen, Jiming; Xu, Zengyu; Li, Xiongwei; Liu, Shi

    2009-04-01

    The reduced activation ferritic/martenstic steel CLF-1 prepared by the Southwestern Institute of Physics in China was irradiated by helium ions with an energy of 5 keV at room temperature using an electron cyclotron resonance (ECR) ion irradiation apparatus. After the irradiation, the helium retention and desorption were investigated using a technique of thermal desorption spectroscopy (TDS). The experiment was conducted with both the normal and welded samples. Blisters were observed after the helium ion irradiation, and the surface density of blisters in the welded samples was lower than that in the non-welded samples. Three desorption peaks were observed in both the non-welded and welded samples. These desorption peaks corresponded to those of blister ruptures and the helium release from the inner bubbles and the defects. The amount of helium retained in the welded samples was approximately the same as that in the non-welded samples, which was much less than other reduced activation materials, such as vanadium alloy and SiC/SiC composites.

  17. Helium Retention and Desorption Behaviour of Reduced Activation Ferritic/Martenstic Steel

    Institute of Scientific and Technical Information of China (English)

    WANG Pinghuai; NOBUTA Yuji; HINO Tomoaki; YAMAUCHI Yuji; CHEN Zilning; XU Zengyu; LI Xiongwei; LIU Shi

    2009-01-01

    The reduced activation ferritic/martenstic steel CLF-1 prepared by the Southwest-ern Institute of Physics in China was irradiated by helium ions with an energy of 5 keV at room temperature using an electron cyclotron resonance (ECR) ion irradiation apparatus. After the irradiation, the helium retention and desorption were investigated using a technique of thermal desorption spectroscopy (TDS). The experiment was conducted with both the normal and welded samples. Blisters were observed after the helium ion irradiation, and the surface density of blisters in the welded samples was lower than that in the non-welded samples. Three desorption peaks were observed in both the non-welded and welded samples. These desorption peaks corresponded to those of blister ruptures and the helium release from the inner bubbles and the defects. The amount of helium retained in the welded samples was approximately the same as that in the non-welded samples, which was much less than other reduced activation materials, such as vanadium alloy and SiC/SiC composites.

  18. Desorption, partitioning, and dechlorination characteristics of PCBs in sediments in interaction with reactive activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hyeok, E-mail: hchoi@uta.edu [Department of Civil Engineering, The University of Texas at Arlington, 416 Yates Street, Arlington, TX 76019-0308 (United States); Environmental and Earth Sciences Program, The University of Texas at Arlington, 500 Yates Street, Arlington, TX 76019-0049 (United States); Lawal, Wasiu [Environmental and Earth Sciences Program, The University of Texas at Arlington, 500 Yates Street, Arlington, TX 76019-0049 (United States); Al-Abed, Souhail R. [National Risk Management Research Laboratory, U.S. Environmental Protection Agency, 26 W. Martin Luther King Dr., Cincinnati, OH 45268 (United States)

    2015-04-28

    Highlights: • Problematic aged real PCBs-contaminated sediment (WHS) was examined. • Performance of reactive activated carbon (RAC) impregnated with Pd–ZVI was tested. • Fate and transport of PCBs bound to WHS in the presence of RAC was fully traced. • Direct mixing configuration was compared with compartment configuration. • Results reflected real world complexities associated with slow desorption of PCBs. - Abstract: Sediment (WHS) in Waukegan Harbor, Illinois, heavily contaminated and aged with polychlorinated biphenyls (PCBs), was treated with reactive activated carbon (RAC) impregnated with palladized iron nanoparticles. Lab test proceeded in a direct mixing configuration of RAC and WHS. A compartment configuration, where RAC was physically separated from WHS, was also designed to trace the sequential transport and fate of PCBs, including desorption, adsorption, dechlorination, and re-partitioning. PCBs, once desorbed from WHS, were immediately sequestrated to RAC and subject to dechlorination. Direct mixing of WHS with RAC was one-order of magnitude more effective for dechlorination than compartment configuration. Compared to their desorption-followed by-adsorption route, direct physical contact of RAC with PCBs bound to WHS exhibited negligible contribution to the availability of PCBs for dechlorination reaction. Addition of RAC even in compartment configuration facilitated PCBs desorption from WHS. However, slow desorption of PCBs limited overall performance, resulting in a five-order of magnitude lower dechlorination yield when compared with treatment of purely aqueous PCBs. The low dechlorination yield reflected real world complexities in treating 3.19% organic carbon-containing WHS aged with PCBs for 40 years. These observations were further supported when compared with results on clean Cesar Creek sediment spiked with 2-chlorinated biphenyls.

  19. Dielectronic Recombination In Active Galactic Nuclei

    Science.gov (United States)

    Lukic, D. V.; Schnell, M.; Savin, D. W.; Altun, Z.; Badnell, N.; Brandau, C.; Schmidt, E. W.; Mueller, A.; Schippers, S.; Sprenger, F.; Lestinsky, M.; Wolf, A.

    2006-01-01

    XMM-Newton and Chandra observations of active galactic nuclei (AGN) show rich spectra of X-ray absorption lines. These observations have detected a broad unresolved transition array (UTA) between approx. 15-17 A. This is attributed to inner-shell photoexcitation of M-shell iron ions. Modeling these UTA features is currently limited by uncertainties in the low-temperature dielectronic recombination (DR) data for M-shell iron. In order to resolve this issue, and to provide reliable iron M-shell DR data for plasma modeling, we are carrying out a series of laboratory measurements using the heavy-ion Test Storage Ring (TSR) at the Max-Plank-Institute for Nuclear Physics in Heidelberg, Germany. Currently, laboratory measurements of low temperature DR can only be performed at storage rings. We use the DR data obtained at TSR, to calculate rate coefficients for plasma modeling and to benchmark theoretical DR calculations. Here we report our recent experimental results for DR of Fe XIV forming Fe XIII.

  20. Biodegradation of persistent organics can overcome adsorption-desorption hysteresis in biological activated carbon systems.

    Science.gov (United States)

    Abromaitis, V; Racys, V; van der Marel, P; Meulepas, R J W

    2016-04-01

    In Biological Activated Carbon (BAC) systems, persistent organic pollutants can be removed through a combination of adsorption, desorption and biodegradation. These processes might be affected by the presence of other organics, especially by the more abundant easily-biodegradable organics, like acetate. In this research these relations are quantified for the removal of the persistent pharmaceutical metoprolol. Acetate did not affect the adsorption and desorption of metoprolol, but it did greatly enhance the metoprolol biodegradation. At least part of the BAC biomass growing on acetate was also able to metabolise metoprolol, although metoprolol was only converted after the acetate was depleted. The presence of easily-degradable organics like acetate in the feeding water is therefore beneficial for the removal of metoprolol in BAC systems. The isotherms obtained from metoprolol adsorption and desorption experiments showed that BAC systems are subject to hysteresis; for AC bioregeneration to take place the microbial biomass has to reduce the concentration at the AC-biomass interface 2.7 times compared to the concentration at which the carbon was being loaded. However, given the threshold concentration of the MET degrading microorganisms (<0.08 μg/L) versus the average influent concentration (1.3 μg/L), bioregeneration is feasible.

  1. Multiple biological activities of human recombinant interleukin 1.

    OpenAIRE

    Dinarello, C A; Cannon, J. G.; Mier, J W; Bernheim, H. A.; LoPreste, G; Lynn, D L; Love, R N; Webb, A C; Auron, P. E.; Reuben, R C

    1986-01-01

    Complementary DNA coding for human monocyte interleukin 1 (IL-1), pI 7 form, was expressed in Escherichia coli. During purification, IL-1 activity on murine T cells was associated with the recombinant protein. Homogeneous human recombinant IL-1 (hrIL-1) was tested in several assays to demonstrate the immunological and inflammatory properties attributed to this molecule. hrIL-1 induced proliferative responses in a cloned murine T cell in the presence of suboptimal concentrations of mitogen, wh...

  2. Adsorption and desorption of mixtures of organic vapors on beaded activated carbon.

    Science.gov (United States)

    Wang, Haiyan; Jahandar Lashaki, Masoud; Fayaz, Mohammadreza; Hashisho, Zaher; Philips, John H; Anderson, James E; Nichols, Mark

    2012-08-01

    In this study, adsorption and desorption of mixtures of organic compounds commonly emitted from automotive painting operations were experimentally studied. A mixture of two alkanes and a mixture of eight organic compounds were adsorbed onto beaded activated carbon (BAC) and then thermally desorbed under nitrogen. Following both adsorption and regeneration, samples of the BAC were chemically extracted. Gas chromatography-mass spectrometry (GC-MS) was used to quantify the compounds in the adsorption and desorption gas streams and in the BAC extracts. In general, for both adsorbate mixtures, competitive adsorption resulted in displacing low boiling point compounds by high boiling point compounds during adsorption. In addition to boiling point, adsorbate structure and functionality affected adsorption dynamics. High boiling point compounds such as n-decane and 2,2-dimethylpropylbenzene were not completely desorbed after three hours regeneration at 288 °C indicating that these two compounds contributed to heel accumulation on the BAC. Additional compounds not present in the mixtures were detected in the extract of regenerated BAC possibly due to decomposition or other reactions during regeneration. Closure analysis based on breakthrough curves, solvent extraction of BAC and mass balance on the reactor provided consistent results of the amount of adsorbates on the BAC after adsorption and/or regeneration. PMID:22742925

  3. Visualization and Measurement of Adsorption/Desorption Process of Ethanol in Activated Carbon Adsorber

    Science.gov (United States)

    Asano, Hitoshi; Murata, Kenta; Takenaka, Nobuyuki; Saito, Yasushi

    Adsorption refrigerator is one of the efficient tools for waste heat recovery, because the system is driven by heat at relative low temperature. However, the coefficient of performance is low due to its batch operation and the heat capacity of the adsorber. In order to improve the performance, it is important to optimize the configuration to minimize the amount of driving heat, and to clarify adsorption/desorption phenomena in transient conditions. Neutron radiography was applied to visualize and measure the adsorption amount distribution in an adsorber. The visualization experiments had been performed at the neutron radiography facility of E-2 port of Kyoto University Research Reactor. Activated carbon and ethanol were used as the adsorbent and refrigerant. From the acquired radiographs, adsorption amount was quantitatively measured by applying the umbra method using a checkered neutron absorber with boron powder. Then, transient adsorption and desorption processes of a rectangular adsorber with 84 mm in width, 50 mm in height and 20 mm in depth were visualized. As the result, the effect of fins in the adsorbent layer on the adsorption amount distribution was clearly visualized.

  4. A new method of regenerating activated carbon by thermal desorption with liquid water under subcritical conditions

    Energy Technology Data Exchange (ETDEWEB)

    Salvador, F.; Sanchez Jimenez, C. [Universidad de Salamanca, Salamanca (Spain). Dept. de Quimica Fisica

    1996-06-01

    This paper discusses a new procedure for regenerating activated carbon based on thermal desorption with liquid water under subcritical conditions (300{degree}C and 120 atm). The method was assayed with three types of activated carbons exhausted with phenols (phenol and 4-nitrophenol), textile dyes (sirius red C.I.:29080 and orange II C.I.:15510) and pesticides (carbonfuran and atrazine). In all cases, total recovery of the adsorption capacity was achieved, even after seven regenerations. The mechanism and factors involved in regeneration were investigated using the TPD technique in liquid phase. The differences and advantages of this procedure as compared with others, such as thermal regeneration or regeneration with supercritical CO{sub 2} are discussed. 20 refs., 5 figs., 1 tab.

  5. 75 FR 42114 - Office of Biotechnology Activities; Recombinant DNA Research: Proposed Action Under the NIH...

    Science.gov (United States)

    2010-07-20

    ... HUMAN SERVICES National Institutes of Health Office of Biotechnology Activities; Recombinant DNA Research: Proposed Action Under the NIH Guidelines for Research Involving Recombinant DNA Molecules (NIH... transgenic rodents by recombinant DNA technology must be registered with the Institutional...

  6. Activity of recombinant factor VIIa under different conditions in vitro

    DEFF Research Database (Denmark)

    Bladbjerg, Else-Marie; Jespersen, Jørgen

    2008-01-01

    Recombinant activated factor VII (NovoSeven; Novo Nordisk A/S, Måløv, Denmark) is an effective drug for treatment of bleeding in patients with haemophilia A or B and inhibitors. Little is known about physiological conditions influencing the efficacy of recombinant activated factor VII. We...... investigated the in-vitro effects of pH, temperature, and haemodilution on the activity of recombinant activated factor VII. Samples from eight healthy volunteers were spiked with recombinant activated factor VII (final concentration 1.7 microg/ml) and adjusted to pH 6.0, 6.5, 7.0, and 7.4 or analysed at 30...... activity in plasma. Significant effects of pH were observed for clotting time, clot formation time, maximum clot firmness, and factor VII coagulant activity in the direction of longer clot formation times and less firm clots with decreasing pH. Temperature had significant effects on clotting time, clot...

  7. 4-MCHM sorption to and desorption from granular activated carbon and raw coal.

    Science.gov (United States)

    Jeter, T Scott; Sarver, Emily A; McNair, Harold M; Rezaee, Mohammad

    2016-08-01

    4-Methylcyclohexanemethanol (4-MCHM) is a saturated higher alicyclic primary alcohol that is used in the froth flotation process for cleaning coal. In early 2014, a large spill of crude chemical (containing primarily 4-MCHM) to the Elk River near Charleston, WV contaminated the local water supply. Carbon filters at the affected water treatment facility quickly became saturated, and the contaminated water was distributed to nearby homes and businesses. Sorption of 4-MCHM to granular activated carbon (GAC) was studied in the laboratory using head space (HS) analysis via gas chromatography with a flame ionization detector (GC-FID). Sorption to raw coal was also investigated, since this material may be of interest as a sorbent in the case of an on-site spill. As expected, sorption to both materials increased with decreased particle size and with increased exposure time; although exposure time proved to be much more important in the case of GAC than for coal. Under similar conditions, GAC sorbed more 4-MCHM than raw coal (e.g., 84.9 vs. 63.1 mg/g, respectively, for 20 × 30 mesh particles exposed to 860 mg/L 4-MCHM solution for 24 h). Desorption from both materials was additionally evaluated. Interestingly, desorption of 4-MCHM on a mass per mass basis was also higher for GAC than for raw coal. Overall, results indicated that GAC readily sorbs 4-MCHM but can also readily release a portion of the chemical, whereas coal sorbs somewhat less 4-MCHM but holds it tightly. PMID:27219291

  8. A recombinant wheat serpin with inhibitory activity

    DEFF Research Database (Denmark)

    Rasmussen, Søren K; Dahl, Søren Weis; Nørgård, Anette;

    1996-01-01

    to the subfamily of protein Z-type serpins and the amino acid sequence is 70%, identical with the barley serpins BSZ4 and BSZx and 27-33% identical with human serpins such as alpha(1)-proteinase inhibitor, antithrombin III, and plasminogen activator inhibitor. The cDNA was subcloned in the pET3d expression vector...

  9. Oxygen Sorption and Desorption Properties of Selected Lanthanum Manganites and Lanthanum Ferrite Manganites

    DEFF Research Database (Denmark)

    Nielsen, Jimmi; Skou, Eivind M.; Jacobsen, Torben

    2015-01-01

    by X‐ray diffractometry, atomic force microscopy (AFM), and BET surface adsorption. Sorbed oxygen could be distinguished from oxygen originating from stoichiometry changes. The results indicated that there is one main site for oxygen sorption/desorption. The amount of sorbed oxygen was monitored over...... time at different temperatures. Furthermore, through data analysis it was shown that the desorption peak associated with oxygen sorption is described well by second‐order desorption kinetics. This indicates that oxygen molecules dissociate upon adsorption and that the rate‐determining step...... for the desorption reaction is a recombination of monatomic oxygen. Typical problems with re‐adsorption in this kind of TPD setup were revealed to be insignificant by using simulations. Finally, different key parameters of sorption and desorption were determined, such as desorption activation energies, density...

  10. Supercritical CO2 desorption of activated carbon loaded with 2,2,3,3-tetrafluoro-1-propanol in a rotating packed bed.

    Science.gov (United States)

    Tan, Chung-Sung; Lee, Pei-Lun

    2008-03-15

    Desorption of activated carbon loaded with 2,2,3,3-tetrafluoro-1-propanol (TFP) by supercritical carbon dioxide in a rotating packed bed was investigated in this study. The experimental data show that the time required to achieve complete desorption of TFP from activated carbon in a rotating packed bed was much lower than that in a static packed bed. The reduction of desorption time is attributed to the presence of centrifugal force. The supercritical CO2 desorption efficiency in a rotating packed bed was observed to increase with increasing rotation speed, pressure, and C02 flow rate. To enhance desorption efficiency, a smaller activated carbon particle size was suggested. At low operating pressures such as 8.96 and 11.72 MPa, a better desorption efficiency was found to occur at lower temperatures in a temperature range of 305-335 K. However, at high operating pressures such as 15.86 MPa, a temperature of 315 K was found to be more appropriate for desorption, as compared to other temperatures. Due to a reduction of packed bed volume and an increase in desorption efficiency, supercritical CO2 desorption in a rotating packed bed is suggested for recovering TFP from the exhaust gases. PMID:18409651

  11. Application of acid-activated Bauxsol for wastewater treatment with high phosphate concentration: Characterization, adsorption optimization, and desorption behaviors.

    Science.gov (United States)

    Ye, Jie; Cong, Xiangna; Zhang, Panyue; Zeng, Guangming; Hoffmann, Erhard; Liu, Yang; Wu, Yan; Zhang, Haibo; Fang, Wei; Hahn, Hermann H

    2016-02-01

    Acid-activated Bauxsol was applied to treat wastewater with high phosphate concentration in a batch adsorption system in this paper. The effect of acid activation on the change of Bauxsol structure was systematically investigated. The mineralogical inhomogeneity and intensity of Bauxsol decreased after acid activation, and FeCl3·2H2O and Al(OH)3 became the dominant phases of acid-activated Bauxsol adsorption. Moreover, the BET surface area and total pore volume of Bauxsol increased after acid activation. Interaction of initial solution pH and adsorption temperature on phosphate adsorption onto acid-activated Bauxsol was investigated by using response surface methodology with central composite design. The maximum phosphate adsorption capacity of 192.94 mg g(-1) was achieved with an initial solution pH of 4.19 and an adsorption temperature of 52.18 °C, which increased by 7.61 times compared with that of Bauxsol (22.40 mg g(-1)), and was higher than other adsorbents. Furthermore, the desorption studies demonstrated that the acid-activated Bauxsol was successfully regenerated with 0.5 mol L(-1) HCl solution. The adsorption capacity and desorption efficiency of acid-activated Bauxsol maintained at 80.48% and 93.02% in the fifth adsorption-desorption cycle, respectively, suggesting that the acid-activated Bauxsol could be repeatedly used in wastewater treatment with high phosphate concentration.

  12. Desorption experiments and modeling of micropollutants on activated carbon in water phase: application to transient concentrations mitigation

    OpenAIRE

    Bourneuf, Séda; Jacob, Matthieu; Albasi, Claire; Sochard, Sabine; Richard, Romain; Manero, Marie-Hélène

    2016-01-01

    International audience Experimental studies and numerical modeling were conducted to assess the feasibility of a granular activated carbon column to buffer load variations of contaminants before wastewater treatment devices. Studies of cycles of adsorption, and more especially desorption, of methyldiethanolamine (MDEA) and 2,4-dimethylphenol (2,4-DMP) have been carried out on granular activated carbon (GAC). Dynamic variations of contaminants concentrations were run at several conditions o...

  13. Theoretical and Experimental Study on the Adsorption and Desorption of Methane by Granular Activated Carbon at 25 ℃

    Institute of Scientific and Technical Information of China (English)

    E. Salehi; V. Taghikhani; C. Ghotbi; E. Nemati Lay; A. Shojaei

    2007-01-01

    A theoretical and experimental study was conducted to accurately determine the amount of adsorption and desorption of methane by various Granular Activated Carbon (GAC) under different physical conditions. To carry out the experiments, the volumetric method was used up to 500 psia at constant temperature of 25 ℃. In these experiments, adsorption as well as desorption capacities of four different GAC in the adsorption of methane, the major constituent of natural gas, at various equilibrium pressures and a constant temperature were studied. Also, various adsorption isotherm models were used to model the experimental data collected from the experiments. The accuracy of the results obtained from the adsorption isotherm models was compared and the values for the regressed parameters were reported. The results shows that the physical characteristics of activated carbons such as BET surface area, micropore volume, packing density, and pore size distribution play an important role in the amount of methane to be adsorbed and desorbed.

  14. Comparing the desorption and biodegradation of low concentrations of phenanthrene sorbed to activated carbon, biochar and compost

    DEFF Research Database (Denmark)

    Marchal, Geoffrey; Smith, Kilian E.C.; Rein, Arno;

    2013-01-01

    ±0.3%, respectively) and compost (1.3±0.21%, similar for all media). Secondly, the mineralization of phenanthrene sorbed to AC, charcoal and compost by Sphingomonas sp. 10-1 (DSM 12247) was determined. In contrast to the amounts desorbed, phenanthrene mineralization was similar for all the soil amendments at about 56......Carbonaceous soil amendments are applied to contaminated soils and sediments to strongly sorb hydrophobic organic contaminants (HOCs) and reduce their freely dissolved concentrations. This limits biouptake and toxicity, but also biodegradation. To investigate whether HOCs sorbed to such amendments...... can be degraded at all, the desorption and biodegradation of low concentrations of 14C-labelled phenanthrene (⩽5μgL−1) freshly sorbed to suspensions of the pure soil amendments activated carbon (AC), biochar (charcoal) and compost were compared. Firstly, the maximum abiotic desorption of phenanthrene...

  15. Adsorption and desorption of noble gases on activated charcoal: I. 133Xe studies in a monolayer and packed bed.

    Science.gov (United States)

    Scarpitta, S C; Harley, N H

    1990-10-01

    Detailed desorption studies using petroleum-based activated charcoals were conducted in monolayers and packed beds. Less extensive studies were conducted on several other types of charcoal. Kinetic studies, using 133Xe, demonstrated the existence of a micropore volume with entrance capillaries that together determined the response characteristics of charcoal to external concentration gradients of tracer gases. This new two-phase model, composed of micropores and entrance capillaries, describes the desorption dynamics of an adsorbed gas in the presence of water vapor. Condensed water vapor in the entrance capillaries of the charcoal reduced the effective pore radius and increased the diffusion half-time. Water could also adversely affect the integrating capability of the charcoal dramatically if the adsorbed water completely blocked the entrance capillaries. The amount of adsorbed water required to block the capillaries varied with the charcoal type and was termed here as the "break-point." The desorption parameters measured in this work can be used to design an improved passive Rn monitor to effectively integrate during a 3-7 d exposure period by eliminating the adverse effects of water vapor. The improved canister design would provide more accurate and reproducible measurements of indoor Rn concentrations than are currently available. PMID:2398007

  16. Effects and Mechanisms of Mechanical Activation on Hydrogen Sorption/ Desorption of Nanoscale Lithium Nitrides

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, Leon, L.; Yang, Gary, Z.; Crosby, Kyle; Wwan, Xufei. Zhong, Yang; Markmaitree, Tippawan; Osborn, William; Hu, Jianzhi; Kwak, Ja Hun

    2012-04-26

    The objective of this project is to investigate and develop novel, mechanically activated, nanoscale Li3N-based and LiBH4-based materials that are able to store and release {approx}10 wt% hydrogen at temperatures near 100 C with a plateau hydrogen pressure of less than 10 bar. Four (4) material systems have been investigated in the course of this project in order to achieve the project objective. These 4 systems are (i) LiNH2+LiH, (ii) LiNH2+MgH2, (iii) LiBH4, and (iv) LiBH4+MgH2. The key findings we have obtained from these 4 systems are summarized below. *The thermodynamic driving forces for LiNH2+LiH and LiBH4 systems are not adequate to enable H2 release at temperatures < 100 C. *Hydrogen release in the solid state for all of the four systems is controlled by diffusion, and thus is a slow process. *LiNH2+MgH2 and LiBH4+MgH2 systems, although possessing proper thermodynamic driving forces to allow for H2 release at temperatures < 100 C, have sluggish reaction kinetics because of their diffusion-controlled rate-limiting steps. *Reducing particles to the nanometer length scale (< 50 nm) can improve the thermodynamic driving force to enable H2 release at near ambient temperature, while simultaneously enhancing the reaction kinetics as well as changing the diffusion-controlled rate-limiting step to gas desorption-controlled rate-limiting step. This phenomenon has been demonstrated with LiBH4 and offers the hope that further work along this direction will make one of the material systems, i.e., LiBH4, LiBH4+MgH2 and LiNH2+MgH2, possess the desired thermodynamic properties and rapid H2 uptake/release kinetics for on-board applications. Many of the findings and knowledge gained from this project have been published in archival refereed journal articles [1-15] and are accessible by general public. Thus, to avoid a bulky final report, the key findings and knowledge gained from this project will be succinctly summarized, particularly for those findings and knowledge

  17. Improving of understanding of beta-hexachlorocyclohexane (HCH) adsorption on activated carbons by temperature-programmed desorption studies.

    Science.gov (United States)

    Passé-Coutrin, Nady; Maisonneuve, Laetitia; Durimel, Axelle; Dentzer, Joseph; Gadiou, Roger; Gaspard, Sarra

    2016-01-01

    In order to understand the interactions between beta-hexachlorocyclohexane (HCH) and chemical groups at activated carbon (AC) surface, the solid samples were hydrogenated aiming to decrease the amounts of oxygenated groups. Two AC samples designated by BagH2O and BagP1.5 were prepared by water vapor activation and phosphoric acid activation, respectively, of sugarcane bagasse used as an AC precursor. A more simple molecule 1,2,3-trichloropropane (TCP) is used as a model of chlorinated compound. The AC were characterized by infrared, X-ray photoelectron spectroscopy (XPS), Raman resonance spectroscopies, as well as temperature-programmed desorption coupled with mass spectrometry (TPD-MS). BagP1.5 and BagH2O AC surface contained oxygenated groups. Upon hydrogenation, a decrease of most of these group amxounts was observed for both samples, while hydroxyl groups increased. On the basis of temperature-programmed desorption data obtained for AC samples contaminated with TCP or HCH, it was possible to determine the type of hydrogen bond formed between each AC and HCH. PMID:26018287

  18. Localization of an O-glycosylated site in the recombinant barley alpha-amylase 1 produced in yeast and correction of the amino acid sequence using matrix-assisted laser desorption/ionization mass spectrometry of peptide mixtures

    DEFF Research Database (Denmark)

    Andersen, Jens S.; Søgaard, M; Svensson, B;

    1994-01-01

    , and analyzed directly by MALDI-MS. Based on the three mass spectrometric peptide maps, an error in the sequence deduced from cDNA, resulting in a mass difference of 28 Da, was located to a sequence stretch of 5 amino acid residues; furthermore, a dihexose substituent was identified on Thr410. Subsequent Edman...... degradation of two selected peptides isolated from the endoproteinase Lys-C digest corrected the sequence to be Val instead of Ala in position 284 and confirmed the O-glycosylation. These results demonstrate that the direct peptide mixture analysis by MALDI-MS is a rapid and sensitive method for protein......Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) of peptide mixtures was used to characterize recombinant barley alpha-amylase 1, produced in yeast. Three peptide mixtures were generated by cleavage with CNBr, digestion with endoproteinase Lys-C and Asp-N, respectively...

  19. Expression of recombination-activating genes and T cell receptor gene recombination in the human T cell leukemia cell line

    Institute of Scientific and Technical Information of China (English)

    ZOU Hong-yun; MA Li; MENG Min-jie; YAO Xin-sheng; LIN Ying; WU Zhen-qiang; HE Xiao-wei; WANG Ju-fang; WANG Xiao-ning

    2007-01-01

    Background Recent studies have suggested that mature T cells can change their specificity through reexpression of recombination-activating genes (RAG) and RAG-mediated V(D)J recombination. This process is named receptor revision and has been observed in mature peripheral T cells from transgenic mice and human donors. However, whether the receptor revision in mature T cells is a random or orientated process remains poorly understood. Here we used the Jurkat human T cell line, which represents a mature stage of T cell development, as a model to investigate the regulation of T cell receptor (TCR) gene recombination.Methods TCR Dβ-Jβ signal joint T cell receptor excision DNA circles (sjTRECs) were determined by nested and seminested PCR. Double-strand DNA breaks at recombination signal sequences (RSSs) in the TCRVβ chain locus were detected by ligation-mediated-PCR. Further analysis of the complementarity-determining region 3 (CDR3) size of the TCRVβ chain was examined by the TCR GeneScan technique.Results RAG1, RAG2, and three crucial components of the nonhomologous DNA end-joining (NHEJ) pathway were readily detected in Jurkat. Characteristics of junctional diversity of Dβ2-Jβ2 signal joints and ds RSS breaks associated with the Dβ25' and Dβ 23' sites were detected in DNA from Jurkat cells. CDR3 size and the gene sequences of the TCRVβ chain did not change during cell proliferation.Conclusions RAG1 and RAG2 and ongoing TCR gene recombination are coexpressed in Jurkat cells, but the ongoing recombination process may not play a role in modification of the TCR repertoire. However, the results suggest that Jurkat could be used as a model for studying the regulation of RAGs and V(D)J recombination and as a "special" model of the coexistence of TCR gene rearrangements and "negative" receptor revision.

  20. Evidence supporting the use of recombinant activated factor VII in congenital bleeding disorders

    DEFF Research Database (Denmark)

    Johansson, Pär I; Ostrowski, Sisse R

    2010-01-01

    Recombinant activated factor VII (rFVIIa, NovoSeven) was introduced in 1996 for the treatment of hemophilic patients with antibodies against coagulation factor VIII or IX.......Recombinant activated factor VII (rFVIIa, NovoSeven) was introduced in 1996 for the treatment of hemophilic patients with antibodies against coagulation factor VIII or IX....

  1. [Comparison of expression and antibacterial activities of recombinant porcine lactoferrin expressed in four Lactobacillus species].

    Science.gov (United States)

    Yu, Hui; Jiang, Yanping; Cui, Wen; Wu, Xiao; He, Jia; Qiao, Xinyuan; Li, Yijing; Tang, Lijie

    2014-09-01

    The coding sequence for the mature peptide of porcine lactoferrin (Plf) was synthesized according to the codon usage of lactobacillus, to establish optimized porcine lactoferrin Lactobacillus expression system. The gene was ligated into the Xho I/BamH I site of Lactobacillus expression vector pPG612.1 and the recombinant plasmid pPG612.1-plf was transformed individually into Lactobacillus casei ATCC393, Lactobacillus pentosus KLDS1.0413, Lactobacillus plantarum KLDS1.0344 or Lactobacillus paracasei KLDS1.0652 by electroporation. After induction with xylose, expression of the recombinant proteins was detected by Western blotting and confocal laser scanning microscopy. Secretion of recombinant Plf proteins from four recombinant species was determined quantitatively by ELISA. The antibacterial activities of recombinant proteins were measured by agar diffusion method. The result shows that Plf was correctly expressed in four species of recombinant lactobacillus, with molecular weight of about 73 kDa. The expression levels in recombinant Lactobacillus casei, Lactobacillus pentosus, Lactobacillus plantarum, Lactobacillus paracasei were 9.6 μg/mL, 10.8 μg/mL, 12.5 μg/mL and 9.9 μg/mL, respectively. Antimicrobial activity experiment shows that the recombinant proteins were active against E. coli, Staphylococcus aureus, Salmonella typhimurium, Listeria, Pasteurella. The recombinant Plf expressed by recombinant Lactobacillus plantarum showed the best antibacterial activity among all recombinant lactobacillus species. These data represent a basis for the development and application of porcine lactoferrin from recombinant lactobacillus.

  2. Recombinant human migration inhibitory factor has adjuvant activity.

    OpenAIRE

    Weiser, W Y; Pozzi, L M; Titus, R G; David, J R

    1992-01-01

    Recombinant human migration inhibitory factor (MIF), isolated through functional expression cloning in COS-1 cells, up-regulates expression of genes encoding HLA-DR and interleukin 1 beta (IL-1 beta) and elaboration of IL-1 beta by human monocyte-derived macrophages. Administration of soluble bovine serum albumin or human immunodeficiency virus 120-kDa glycoprotein (HIV gp120) to mice in the presence of recombinant MIF together with incomplete Freund's adjuvant induced a strong T-cell prolife...

  3. Myelostimulatory activity of recombinant human interleukin-2 in mice

    International Nuclear Information System (INIS)

    In a series of studies designed to extend our understanding of interleukin-2 (IL-2) and to study the effect of biologic response modifiers on bone marrow, we observed that administering recombinant human (rH) IL-2 to normal mice resulted in an increase in the frequency of colony-forming units-culture (CFU-C) in bone marrow. In addition, rH IL-2 was able to accelerate host recovery from cyclophosphamide (CTX)- or radiation-induced bone marrow depression and peripheral blood leukopenia. Not only can rH IL-2 accelerate, in a dose-dependent manner, the return of bone marrow, peripheral blood cellularity, and CFU-C frequency to normal levels following cytoreduction by CTX or irradiation, but it also significantly increases CFU-C frequency to greater than normal levels. Furthermore, rH IL-2 can significantly prolong survival of animals receiving a lethal dose of irradiation or CTX. Thus, multiple mechanisms are responsible for the synergistic therapeutic activity associated with rH IL-2 and CTX. rH IL-2 does not act only as an immunomodulatory agent in the presence or absence of suppressor T cells, but also accelerates host recovery from cytoreductive agents, resulting in decreased leukopenia and perhaps resistances to secondary infection. Thus, rH IL-2 plus chemotherapy may increase therapeutic activity against neoplastic disease, not only by adding immune stimulation to the direct antitumor effect of the drug but also by allowing delivery of higher, more effective doses of chemotherapy

  4. Supercritical fluid extraction and temperature-programmed desorption of phenol and its oxidative coupling products from activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Humayun, R.; Karakas, G.; Dahlstrom, P.R.; Ozkan, U.S.; Tomasko, D.L. [Ohio State Univ., Columbus, OH (United States). Dept. of Chemical Engineering

    1998-08-01

    Activated carbon remains one of the most economical adsorbents for the removal of contaminants from water. In particular, activated carbon is known to have an extremely high affinity for phenol and its derivatives. This has been shown to be the result of a catalytic process wherein activated carbon catalyzes the oxidative coupling reactions of phenol in aqueous solution when molecular oxygen is present. These reactions are believed to be the source of the difficulty of regenerating activated carbon loaded with phenol. This paper reports on efforts toward using supercritical fluids to regenerate activated carbon combined with a concurrent temperature-programmed desorption study to identify reaction products and their binding strength to the carbon surface. The results show unequivocally that part of the phenol is chemisorbed on the surface and part of it undergoes polymerization. Dihydroxybiphenyls and phenoxyphenols are the major reaction products present on the surface. Isotope studies showed that surface carbon atoms do not directly participate in these reactions. Supercritical extraction was found to perform as well as solvent extraction for the regeneration of activated carbon loaded with phenol. However, due to the chemisorbed nature of these oxidative coupling products, the reduced mass-transfer limitations afforded by supercritical extraction cannot improve the overall extent of extraction even though the rate is improved with the addition of cosolvents.

  5. 75 FR 28811 - Office of Biotechnology Activities; Recombinant DNA Research: Proposed Actions Under the NIH...

    Science.gov (United States)

    2010-05-24

    ... HUMAN SERVICES National Institutes of Health Office of Biotechnology Activities; Recombinant DNA Research: Proposed Actions Under the NIH Guidelines for Research Involving Recombinant DNA Molecules (NIH... DNA Advisory Committee and approved by the NIH Director (Section III-A-1). Such research involves...

  6. 75 FR 31795 - Office of Biotechnology Activities; Recombinant DNA Research: Amended Notice of Meeting

    Science.gov (United States)

    2010-06-04

    ..., 2010 (75 FR 28811) is withdrawn. The discussion that was to be held at the June 16-17, 2010 meeting of... HUMAN SERVICES National Institutes of Health Office of Biotechnology Activities; Recombinant DNA... ] under Section III-A-1 of the NIH Guidelines for Research Involving Recombinant DNA Molecules...

  7. The autolytic activity of the recombinant amidase of Staphylococcus saprophyticus is inhibited by its own recombinant GW repeats.

    Science.gov (United States)

    Hell, Wolfgang; Reichl, Sylvia; Anders, Agnes; Gatermann, Sören

    2003-10-10

    The Aas (autolysin/adhesin of Staphylococcus saprophyticus) is a multifunctional surface protein containing two enzymatic domains an N-acetyl-muramyl-L-alanine amidase, an endo-beta-N-acetyl-D-glucosaminidase, and two different regions of repetitive sequences, an N-terminal and a C-terminal repetitive domain. The C-terminal repetitive domain is built up by the repeats R1, R2 and R3, which interconnect the putative active centers of the amidase and glucosaminidase. To investigate the influence of the C-terminal repeats and the N-terminal repeats on the amidase activity, the repetitive domains and fragments of them were cloned and expressed in Escherichia coli. The influence of the different fragments on the activity of the recombinant amidase of the Aas, consisting of the active center of the enzyme and repeat R1, was investigated in a turbidimetric microassay. The different fragments derived from the C-terminal repeats inhibited the amidase activity, while the N-terminal repeats did not influence the activity of the enzyme. The inhibiting activity increased with the number of GW repeats the recombinant fragment contained. Thus we conclude, that the C-terminal GW repeats and not the N-terminal repeats are necessary for the cell wall targeting and the autolytic function of the amidase.

  8. Use of thermal desorption gas chromatography-olfactometry/mass spectrometry for the comparison of identified and unidentified odor active compounds emitted from building products containing linseed oil

    DEFF Research Database (Denmark)

    Clausen, P. A.; Knudsen, Henrik Nellemose; Larsen, K.;

    2008-01-01

    The emission of odor active volatile organic compounds (VOCs) from a floor oil based on linseed oil, the linseed oil itself and a low-odor linseed oil was investigated by thermal desorption gas chromatography combined with olfactometry and mass spectrometry (TD-GC-O/MS). The oils were applied to ...

  9. The negligible photodesorption of methanol ice and the active photon-induced desorption of its irradiation products

    CERN Document Server

    Cruz-Diaz, Gustavo A; Caro, Guillermo M Muñoz; Chen, Y -J

    2016-01-01

    Methanol is a common component of interstellar and circumstellar ice mantles and is often used as an evolution indicator in star-forming regions. The observations of gas-phase methanol in the interiors of dense molecular clouds at temperatures as low as 10 K suggests that a non-thermal ice desorption must be active. Ice photodesorption was proposed to explain the abundances of gas-phase molecules toward the coldest regions. Laboratory experiments were performed to investigate the potential photodesorption of methanol toward the coldest regions. Solid methanol was deposited at 8 K and UV-irradiated at various temperatures starting from 8 K. The irradiation of the ice was monitored by means of infrared spectroscopy and the molecules in the gas phase were detected using quadrupole mass spectroscopy. Fully deuterated methanol was used for confirmation of the results. The photodesorption of methanol to the gas phase was not observed in the mass spectra at different irradiation temperatures. We estimate an upper li...

  10. Vaccine testing of a recombinant activation-associated secreted protein (ASP1) from Ostertagia ostertagi

    OpenAIRE

    Geldhof, Peter; Meyvis, Yves; Vercruysse, Jozef; Claerebout, Edwin

    2008-01-01

    Previous vaccination trials against the economically important cattle parasite Ostertagia ostertagi have indicated the protective capacity of activation-associated secreted proteins (ASPs). The further development of these antigens into a commercial vaccine will require their recombinant expression. The aim of the current study was to clone and express Oo-asp1 in a baculovirus expression system and to evaluate the protective capacity of the recombinant protein against an O. ostertagi challeng...

  11. Molecular mechanism of recombinant liver fatty acid binding protein's antioxidant activity

    OpenAIRE

    YAN, JING; Gong, Yuewen; She, Yi-Min; Wang, Guqi; Roberts, Michael S; Burczynski, Frank J.

    2009-01-01

    Hepatocytes expressing liver fatty acid binding protein (L-FABP) are known to be more resistant to oxidative stress than those devoid of this protein. The mechanism for the observed antioxidant activity is not known. We examined the antioxidant mechanism of a recombinant rat L-FABP in the presence of a hydrophilic (AAPH) or lipophilic (AMVN) free radical generator. Recombinant L-FABP amino acid sequence and its amino acid oxidative products following oxidation were identified by MALDI quadrup...

  12. 75 FR 69687 - Office of Biotechnology Activities Recombinant DNA Research: Proposed Actions Under the NIH...

    Science.gov (United States)

    2010-11-15

    ... HUMAN SERVICES National Institutes of Health Office of Biotechnology Activities Recombinant DNA Research... Biotechnology Activities (OBA). The data to be considered for certifying a new host-vector system can be found... 301-496-9839 or sent by U.S. mail to the Office of Biotechnology Activities, National Institutes...

  13. Activated desorption at heterogeneous interfaces and long-time kinetics of hydrocarbon recovery from nanoporous media

    Science.gov (United States)

    Lee, Thomas; Bocquet, Lydéric; Coasne, Benoit

    2016-06-01

    Hydrocarbon recovery from unconventional reservoirs (shale gas) is debated due to its environmental impact and uncertainties on its predictability. But a lack of scientific knowledge impedes the proposal of reliable alternatives. The requirement of hydrofracking, fast recovery decay and ultra-low permeability--inherent to their nanoporosity--are specificities of these reservoirs, which challenge existing frameworks. Here we use molecular simulation and statistical models to show that recovery is hampered by interfacial effects at the wet kerogen surface. Recovery is shown to be thermally activated with an energy barrier modelled from the interface wetting properties. We build a statistical model of the recovery kinetics with a two-regime decline that is consistent with published data: a short time decay, consistent with Darcy description, followed by a fast algebraic decay resulting from increasingly unreachable energy barriers. Replacing water by CO2 or propane eliminates the barriers, therefore raising hopes for clean/efficient recovery.

  14. Purification and Determination of Inhibitory Activity of Recombinant Soyacystatin Against Papain and Fish Protease

    OpenAIRE

    AKPINAR, Özlem

    2004-01-01

    Recombinant (r-) soyacystatin was characterized for its inhibitory activity against papain and compared to egg white cystatin. r-Soyacystatin expressed in E. coli was purified with phenyl-Sepharose and DEAE 4.33 fold as a recombinant protein. Egg white cystatin was purified by using affinity chromatography on cm-papain-Sepharose. Inhibitory activity of r-soyacystatin was similar to that of egg white cystatin. The amount required to inhibit 50% activity of papain used in the assay, 2 pg, was 0...

  15. 76 FR 3150 - Office of Biotechnology Activities; Recombinant DNA Research: Action Under the NIH Guidelines for...

    Science.gov (United States)

    2011-01-19

    ...). On July 20, 2010 the NIH Office of Biotechnology Activities (OBA) published a proposed action (75 FR... HUMAN SERVICES National Institutes of Health Office of Biotechnology Activities; Recombinant DNA... contact OBA by e- mail at oba@od.nih.gov , telephone, 301-496-9838 or mail to the Office of...

  16. 78 FR 12074 - Office of Biotechnology Activities; Recombinant DNA Research: Actions Under the NIH Guidelines...

    Science.gov (United States)

    2013-02-21

    ... containing an HA from the Goose/Guangdong/1/96 lineage should become an HHS Select Agent (77 FR 63783... HUMAN SERVICES National Institutes of Health Office of Biotechnology Activities; Recombinant DNA... recommendations of the RAC, the NIH Office of Biotechnology Activities (OBA) concluded that more specific...

  17. Experimental and Theoretical Study of the Effect of Moisture on Methane Adsorption and Desorption by Activated Carbon at 273.5 K

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Adsorption and desorption of methane by activated carbon (AC) at constant temperature and at various pressures were investigated. The effect of moisture was also studied. A volumetric method was used, up to 40 bar, at a temperature of 273.5 K. Results of a dry AC sample were compared with those obtained from a moist sample and two different ACs with different physical and surface properties were used. As expected, the results showed that the existence of moisture, trapped in the AC pores, could lead to a decrease in the amount of methane adsorbed and a decrease in the amount of methane delivered during desorption. To model the experimental results, a large variety of adsorption isotherms were used. The regressed parameters for the adsorption isotherms were obtained using the experimental data generated in the present study. The accuracy of the results obtained from the different adsorption isotherms was favorably compared.

  18. Antibacterial Activity of Recombinant Pig Intestinal Parasite Cecropin P4 Peptide Secreted from Pichia pastoris.

    Science.gov (United States)

    Song, Ki-Duk; Lee, Woon-Kyu

    2014-02-01

    Cecropins (Cec) are antibacterial peptides and their expression is induced in a pig intestinal parasite Ascaris suum by bacterial infection. To explore the usefulness of its activity as an antibiotic, CecP4 cDNA was prepared and cloned into the pPICZ B expression vector and followed by the integration into AOX1 locus in Pichia pastoris. The supernatants from cell culture were collected after methanol induction and concentrated for the test of antimicrobial activity. The recombinant P. patoris having CecP4 showed antimicrobial activity when tested against Staphyllococcus aureus in disc diffusion assay. We selected one of the CecP4 clones (CecP4-2) and performed further studies with it. The growth of recombinant P. pastoris was optimized using various concentration of methanol, and it was found that 2% methanol in the culture induced more antibacterial activity, compared to 1% methanol. We extended the test of antimicrobial activity by applying the concentrated supernatant of CecP4 culture to Pseudomonas aeruginosa and E. coli respectively. Recombinant CecP4 also showed antimicrobial activity against both Pseudomona and E. coli, suggesting the broad spectrum of its antimicrobial activity. After improvements for the scale-up, it will be feasible to use recombinant CecP4 for supplementation to the feed to control microbial infections in young animals, such as piglets. PMID:25049952

  19. Sorption-Desorption Behavior of Newly synthesized N-(1H-Benzimidazole -2 ylmethyl) Acetamide (ABNZ) on Selected Soils and its Antifungal activity

    International Nuclear Information System (INIS)

    A batch equilibrium method has been utilized to investigate the adsorption-desorption behavior of a versatile commercially available fungicide N-(1H-benzimidazole-2ylmethyl) acetamide (ABNZ) on four Pakistani soils geographically distant, from hilly to desert areas. Both qualitative and quantitative analysis has been done for sorption-desorption behavior of ABNZ. These analyses are done in the different concentration of fungicide (0-0.25, 0.25-0.5, 0.5-0.75). Based on statistical analysis ABNZ execute the Freundlich adsorption isotherm in all four tested soils having values of slope n<1 resembling the L-type curve. The distribution co-efficient K/sub d(ads)/ ranges from (2.66 to 12.42 ml/meu g/sup -1/) indicating low adsorption of ABNZ overall. Sorption increases with soil organic carbon content, exhibited greater degree of adsorption for hilly soil and least adsorption on sandy soil of Multan, Punjab. Desorption studies reveal that the adsorbed fungicide is firmly retained by soil particles and present a certain degree of irreversibility. The results indicate that the soil organic matters followed by clay content are the most important soil properties governing the fungicide sorption capacity. Compound N-(1H- benzimidazole -2-ylmethyl) acetamide (ABNZ) showed maximum antifungal activity compared to rest of the tested compound. This anti-fungal activity is substantial in comparison to other pesticides. It causes 40% inhibition of Microsporum canis and Fusarium solani. (author)

  20. Adsorption and desorption of noble gases on activated charcoal: II. 222Rn studies in a monolayer and packed bed.

    Science.gov (United States)

    Scarpitta, S C; Harley, N H

    1990-10-01

    The adsorptive and desorptive characteristics of canisters containing a petroleum-based charcoal were investigated under controlled conditions of temperature, relative humidity, and Rn concentration. Charcoals exposed in a monolayer and packed bed during exposure intervals of 1-7 d demonstrate that Rn adsorption and desorption are dependent on bed depth and the amount of water adsorbed. Changes in the adsorptive and desorptive properties of the charcoal occurred near the break-point where the pores became occluded by water vapor that condenses in the entrance capillaries. Radon-222 adsorption is decreased by an order of magnitude as the amount of adsorbed water exceeds the break-point of the charcoal. The reduction in pore surface due to adsorbed water results in a marked increase in the rate of Rn loss from exposed canisters, accounting for reduced adsorption. The apparent desorption time-constant for a 2-cm bed of loose Witco 6 x 10 mesh charcoal containing 0.220-0.365 kg H2O kg-1 is typically between 2-8 h. The apparent desorption time-constant for an equivalent packed bed containing a water vapor content of 0.026-0.060 kg H2O kg-1, which is below the break-point of the charcoal, is about 15-30 h. Conventional charcoal canisters, if exposed in the fully-opened configuration, can achieve the break-point in less than 4 d at 70% humidity. The use of a diffusion barrier would allow for longer exposure times until the break-point of the charcoal is achieved. PMID:2398008

  1. Characterization of ATPase Activity of Recombinant Human Pif1

    Institute of Scientific and Technical Information of China (English)

    Yu HUANG; Deng-Hong ZHANG; Jin-Qiu ZHOU

    2006-01-01

    Saccharomyces cerevisiae Pif1p helicase is the founding member of the Pif1 subfamily that is conserved from yeast to human. The potential human homolog of the yeast PIF1 gene has been cloned from the cDNA library of the Hek293 cell line. Here, we described a purification procedure of glutathione Stransferase (GST)-fused N terminal truncated human Pif1 protein (hPif1△N) from yeast and characterized the enzymatic kinetics of its ATP hydrolysis activity. The ATPase activity of human Pif1 is dependent on divalent cation, such as Mg2+, Ca2+ and single-stranded DNA. Km for ATP for the ATPase activity is approximately 200 μM. As the ATPase activity is essential for hPif1's helicase activity, these results will facilitate the further investigation on hPif1.

  2. Base composition, selection, and phylogenetic significance of indels in the recombination activating gene-1 in vertebrates

    NARCIS (Netherlands)

    Chiari, Y.; Meijden, van der A.; Madsen, O.; Vences, M.; Meyer, A.

    2009-01-01

    Background: The Recombination Activating Proteins, RAG1 and RAG2, play a crucial role in the immune response in vertebrates. Among the nuclear markers currently used for phylogenetic purposes, Rag1 has especially enjoyed enormous popularity, since it successfully contributed to elucidating the relat

  3. Recombinant activated protein C attenuates coagulopathy and inflammation when administered early in murine pneumococcal pneumonia

    NARCIS (Netherlands)

    M. Schouten; C. van 't Veer; J.J.T.H. Roelofs; B. Gerlitz; B.W. Grinnell; M. Levi; T. van der Poll

    2011-01-01

    Recombinant human activated protein C (APC), which has both anticoagulant and anti-inflammatory properties, improves survival of patients with severe sepsis. This beneficial effect is especially apparent in patients with pneumococcal pneumonia. Earlier treatment with APC in sepsis has been associate

  4. Evidence for reduced charge recombination in carbon nanotube/perovskite-based active layers

    Science.gov (United States)

    Bag, Monojit; Renna, Lawrence A.; Jeong, Seung Pyo; Han, Xu; Cutting, Christie L.; Maroudas, Dimitrios; Venkataraman, D.

    2016-10-01

    Using impedance spectroscopy and computation, we show that incorporation of multi-walled carbon nanotubes (MWCNTs) in the bulk of the active layer of perovskite-based solar cells reduces charge recombination and increases the open circuit voltage. An ∼87% reduction in recombination was achieved when MWCNTs were introduced in the planar-heterostructure perovskite solar cell containing mixed counterions. The open circuit voltage (Voc) of perovskite/MWCNTs devices was increased by 70 mV, while the short circuit current density (Jsc) and fill factor (FF) remained unchanged.

  5. [Expression, purification of recombinant cationic peptide AIK in Escherichia coli and its antitumor activity].

    Science.gov (United States)

    Fan, Fangfang; Sun, Huiying; Xu, Hui; Liu, Jiawei; Zhang, Haiyuan; Li, Yilan; Ning, Xuelian; Sun, Yue; Bai, Jing; Fu, Songbin; Zhou, Chunshui

    2015-12-01

    AIK is a novel cationic peptide with potential antitumor activity. In order to construct the AIK expression vector by Gateway technology, and establish an optimal expression and purification method for recombinant AIK, a set of primers containing AttB sites were designed and used to create the AttB-TEV-FLAG-AIR fusion gene by overlapping PCR. The resulting fusion gene was cloned into the donor vector pDONR223 by attB and attP mediated recombination (BP reaction), then, transferred into the destination vector pDESTl 5 by attL and attR mediated recombination (LR reaction). All the cloning was verified by both colony PCR and DNA sequencing. The BL21 F. coli transformed by the GST-AIR expression plasmid was used to express the GST-AIK fusion protein with IPTG induction and the induction conditions were optimized. GST-AIR fusion protein was purified by glutathione magnetic beads, followed by rTEV cleavage to remove GST tag and MTS assay to test the growth inhibition activity of the recombinant AIR on human leukemia HL-60 cells. We found that a high level of soluble expression of GST-AIK protein (more than 30% out of the total bacterial proteins) was achieved upon 0.1 mmol/L ITPG induction for 4 h at 37 °C in the transformed BL21 F. coli with starting OD₆₀₀ at 1.0. Through GST affinity purification and rTEV cleavage, the purity of the resulting recombinant AIK was greater than 95%. And the MTS assays on HL-60 cells confirmed that the recombinant AIK retains an antitumor activity at a level similar to the chemically synthesized AIK. Taken together, we have established a method for expression and purification of recombinant AIK with a potent activity against tumor cells, which will be beneficial for the large-scale production and application of recombinant AIK in the future. PMID:27093838

  6. Refolding techniques for recovering biologically active recombinant proteins from inclusion bodies.

    Science.gov (United States)

    Yamaguchi, Hiroshi; Miyazaki, Masaya

    2014-02-20

    Biologically active proteins are useful for studying the biological functions of genes and for the development of therapeutic drugs and biomaterials in a biotechnology industry. Overexpression of recombinant proteins in bacteria, such as Escherichia coli, often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. As inclusion bodies contain relatively pure and intact proteins, protein refolding is an important process to obtain active recombinant proteins from inclusion bodies. However, conventional refolding methods, such as dialysis and dilution, are time consuming and, often, recovered yields of active proteins are low, and a trial-and-error process is required to achieve success. Recently, several approaches have been reported to refold these aggregated proteins into an active form. The strategies largely aim at reducing protein aggregation during the refolding procedure. This review focuses on protein refolding techniques using chemical additives and laminar flow in microfluidic chips for the efficient recovery of active proteins from inclusion bodies.

  7. Antitumor activity of recombinant interleukin 6 in mice

    OpenAIRE

    1990-01-01

    IL-6 possesses multiple biologic activities that affect a broad range of cells including those directly involved in immune responses as well as cells important in the systemic response to infection or trauma. We now show that purified human rIL-6, when administered alone at relatively high doses that are comparable to therapeutic levels of IL- 2, mediated substantial reductions in the number of pulmonary and hepatic micrometastases from four distinct syngeneic tumors. Unlike IL- 2, IL-6 injec...

  8. Anti-HBV activity of TRL mediated by recombinant adenovirus

    Institute of Scientific and Technical Information of China (English)

    Wei-Dong Gong; Ya Zhao; Jun Yi; Jin Ding; Jun Liu; Cai-Fang Xue

    2005-01-01

    AIM: To investigate the inhibitive effect of hepatitis B virus (HBV)-TRL on HBV replication. METHODS: Based on previously constructed pcDNA3.1 (-)/TRL, TR, TRmut, HBV core protein (HBVc) and hEDN, interest gene sequences TRL, TR, HBVc and hEDN were inserted into adenovirus shuttle plasmid pDC316 respectively and co-transfected HEK293 cells with rescue plasmid pBHGlox(delta)E1,3Cre to acquire RAd/TRL, TR, HBVcand hEDN. And then RAds were identified, amplified and the titers in HEK293 cells were determined. RAd/TRL and TR were named as the experimental groups, and others were control ones. After HepG2.2.15 cells were infected, RAd/TRL expression was identified by indirect immunofluorescence staining. Supernatant HBV-DNA content was determined by fluorescent quantification PCR. Meanwhile, metabolism of HepG2.2.15 cells was evaluated by MTT colorimetry.RESULTS: RAd vectors with distinct interest gene sequence were successfully constructed. Effective expression of RAd/TRL in HepG2.2.15 cells resulted in a significant decrease of supernatant HBV-DNA content compared to RAd/TR (0.63±0.14 vs 1.60±0.47, P = 0.0266, <0.05) andother control groups (0.63±0.14 vs 8.50±2.78, 8.25±2.26,8.25±2.29, 8.50±1.51, 8.57±1.63, P<0.01). MTT assaysuggested that there were no significant differences in cell metabolic activity between groups (P>0.05).CONCLUSION: The construction and expression of RAd/TRL has been achieved and it could inhibit HBV replication successfully, which has laid the foundation for further research on anti-HBV activity in vivo.

  9. Antibacterial Activity of Recombinant Pig Intestinal Parasite Cecropin P4 Peptide Secreted from Pichia pastoris

    OpenAIRE

    Song, Ki-Duk; Lee, Woon-Kyu

    2014-01-01

    Cecropins (Cec) are antibacterial peptides and their expression is induced in a pig intestinal parasite Ascaris suum by bacterial infection. To explore the usefulness of its activity as an antibiotic, CecP4 cDNA was prepared and cloned into the pPICZ B expression vector and followed by the integration into AOX1 locus in Pichia pastoris. The supernatants from cell culture were collected after methanol induction and concentrated for the test of antimicrobial activity. The recombinant P. patoris...

  10. Differential effects of age on chicken heterophil functional activation by recombinant chicken interleukin-2

    OpenAIRE

    Kogut, Michael; Rothwell, Lisa; Kaiser, Pete

    2002-01-01

    Interleukin-2 (IL-2) exercises an array of biological effects on many cells including the functional activation of cells of the innate immune response. Heterophils, the avian equivalent of the neutrophil, function as professional phagocytes to aid in regulation of innate host defenses. The objective of the present studies was to examine the effects of recombinant chicken IL-2 (rChIL-2) on functional activities of heterophils from chickens during the first 3 weeks after hatch. Peripheral blood...

  11. Characterization and biological activities of recombinant human plasminogen kringle 1-3 produced in Escherichia coli.

    Science.gov (United States)

    You, Weon-Kyoo; So, Seung-Ho; Sohn, Young-Doug; Lee, Hyosil; Park, Doo-Hong; Chung, Soo-Il; Chung, Kwang-Hoe

    2004-07-01

    Angiogenesis, the formation of new capillaries from preexisting blood vessels, is involved in many pathological conditions, for example, tumorigenesis, diabetic retinopathy, and rheumatoid arthritis. Angiostatin, which contains the kringle 1-4 domains of plasminogen, is known to be a potent inhibitor of angiogenesis and a strong suppressor of various solid tumors. In this study, we expressed recombinant protein containing the kringle 1-3 domains of human plasminogen in Escherichia coli and investigated its biological activities. The protein was successfully refolded from inclusion bodies and purified at a 30% overall yield, as a single peak by HPLC. The purified recombinant protein had biochemical properties that were similar to those of the native form, which included molecular size, lysine-binding capacity, and immunoreactivity with a specific antibody. The recombinant protein was also found to strongly inhibit the proliferation of bovine capillary endothelial cells in vitro, and the formation of new capillaries on chick embryos. In addition, it suppressed the growth of primary Lewis lung carcinoma and B16 melanoma in an in vivo mouse model. Our findings suggest that the recombinant kringle 1-3 domains in a prokaryote expression system have anti-angiogenic activities, which may be useful in clinical and basic research in the field of angiogenesis. PMID:15177278

  12. Comparison of real time RT-PCR and flow cytometry methods for evaluation of biological activity of recombinant human erythropoietin

    OpenAIRE

    Sepehrizadeh Z; Tabatabaei Yazdi M; Zarrini GH; Hashemi Bozchlou S; Khoshakhlagh P

    2008-01-01

    Background: Evaluation of bioactivity of recombinant erythropoietin is essential for pharmaceutical industry, quality control authorities and researchers. The purpose of this study was to compare real time RT-PCR and flow cytometry for the assay of biological activity of recombinant erythropoietin. Methods: Three concentrations of recombinant erythropoietin BRP (80, 40 and 20 IU/ml) were injected subcutaneously to mice. After 4 days the blood was collected and used for reticulocyte counts by ...

  13. Activation of multiple mitogen-activated protein kinases by recombinant calcitonin gene-related peptide receptor.

    Science.gov (United States)

    Parameswaran, N; Disa, J; Spielman, W S; Brooks, D P; Nambi, P; Aiyar, N

    2000-02-18

    Calcitonin gene-related peptide is a 37-amino-acid neuropeptide and a potent vasodilator. Although calcitonin gene-related peptide has been shown to have a number of effects in a variety of systems, the mechanisms of action and the intracellular signaling pathways, especially the regulation of mitogen-activated protien kinase (MAPK) pathway, is not known. In the present study we investigated the role of calcitonin gene-related peptide in the regulation of MAPKs in human embryonic kidney (HEK) 293 cells stably transfected with a recombinant porcine calcitonin gene-related peptide-1 receptor. Calcitonin gene-related peptide caused a significant dose-dependent increase in cAMP response and the effect was inhibited by calcitonin gene-related peptide(8-37), the calcitonin gene-related peptide-receptor antagonist. Calcitonin gene-related peptide also caused a time- and concentration-dependent increase in extracellular signal-regulated kinase (ERK) and P38 mitogen-activated protein kinase (P38 MAPK) activities, with apparently no significant change in cjun-N-terminal kinase (JNK) activity. Forskolin, a direct activator of adenylyl cyclase also stimulated ERK and P38 activities in these cells suggesting the invovement of cAMP in this process. Calcitonin gene-related peptide-stimulated ERK and P38 MAPK activities were inhibited significantly by calcitonin gene-related peptide receptor antagonist, calcitonin gene-related peptide-(8-37) suggesting the involvement of calcitonin gene-related peptide-1 receptor. Preincubation of the cells with the cAMP-dependent protein kinase inhibitor, H89 [¿N-[2-((p-bromocinnamyl)amino)ethyl]-5-isoquinolinesulfonamide, hydrochloride¿] inhibited calcitonin gene-related peptide-mediated activation of ERK and p38 kinases. On the other hand, preincubation of the cells with wortmannin ¿[1S-(1alpha,6balpha,9abeta,11alpha, 11bbeta)]-11-(acetyloxy)-1,6b,7,8,9a,10,11, 11b-octahydro-1-(methoxymethyl)-9a,11b-dimethyl-3H-furo[4,3, 2-de]indeno[4,5-h]-2

  14. Study of Desorption Agent for LADS Process

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaojing; Qin Ruyi; Liu Jinlong

    2003-01-01

    This article refers to the procedure for selection, evaluation and development of the LADS-D desorption agent associated with the LADS-A adsorbent used in the non-hydroprocessing adsorptive desulfurization (LADS) process for FCC naphtha developed by LPEC Refining Research Institute. The LADS-D desorption agent can effectively remove the sulfides adsorbed on the LADS-A adsorbent. The saturated LADS-A adsorbent can be instantly regenerated by the LADS-D desorption agent to recover its adsorption activity. The LADS-D desorption agent can not only effectively remove all impurities adsorbed on the adsorbent, but also has strong ability to dissolve the impurities to keep a stable desorption efficiency of adsorbent to be basically commensurate with fresh adsorbent after extended use.

  15. Intein-mediated Rapid Purification of Recombinant Human Pituitary Adenylate Cyclase Activating Polypeptide

    Institute of Scientific and Technical Information of China (English)

    Rong-jie YU; An HONG; Yun DAI; Yuan GAO

    2004-01-01

    In order to obtain the recombinant human PACAP efficiently by intein-mediated single column purification, a gene encoding human PACAP was synthesized and cloned into Escherichia coli expression vector pKYB. The recombinant vector pKY-PAC was transferred into E. coli ER2566 cells and the target protein was over-expressed as a fusion to the N-terminus of a self-cleavable affinity tag. After the PACAPintein-CBD fusion protein was purified by chitin-affinity chromatography, the self-cleavage activity of the intein was induced by DTT and the rhPACAP was released from the chitin-bound intein tag. The activity of the rhPACAP to stimulate cyclic AMP accumulation was detected using the human pancreas carcinoma cells SW1990. Twenty-two milligrams of rhPACAP with the purity over 98% was obtained by single column purification from 1 liter of induced culture. The preliminary biological assay indicated that the rhPACAP, which has an extra Met at its N-terminus compared with the native human PACAP, had the similar activity of stimulating cAMP accumulation with the standard PACAP38 in the SW1990 cells. A new efficient production procedure of the active recombinant human PACAP was established.

  16. Insecticidal activity of two proteases against Spodoptera frugiperda larvae infected with recombinant baculoviruses

    Directory of Open Access Journals (Sweden)

    Nagata Tatsuya

    2010-06-01

    Full Text Available Abstract Background Baculovirus comprise the largest group of insect viruses most studied worldwide, mainly because they efficiently kill agricutural insect pests. In this study, two recombinant baculoviruses containing the ScathL gene from Sarcophaga peregrina (vSynScathL, and the Keratinase gene from the fungus Aspergillus fumigatus (vSynKerat, were constructed. and their insecticidal properties analysed against Spodoptera frugiperda larvae. Results Bioassays of third-instar and neonate S. frugiperda larvae with vSynScathL and vSynKerat showed a decrease in the time needed to kill the infected insects when compared to the wild type virus. We have also shown that both recombinants were able to increase phenoloxidase activity in the hemolymph of S. frugiperda larvae. The expression of proteases in infected larvae resulted in destruction of internal tissues late in infection, which could be the reason for the increased viral speed of kill. Conclusions Baculoviruses and their recombinant forms constitute viable alternatives to chemical insecticides. Recombinant baculoviruses containing protease genes can be added to the list of engineered baculoviruses with great potential to be used in integrated pest management programs.

  17. Recombination-activating gene 1 and 2 (RAG1 and RAG2) in flounder (Paralichthys olivaceus)

    Indian Academy of Sciences (India)

    Xianlei Wang; Xungang Tan; Pei-Jun Zhang; Yuqing Zhang; Peng Xu

    2014-12-01

    During the development of B and T lymphocytes, Ig and TCR variable region genes are assembled from germline V, D, and J gene segments by a site-specific recombination reaction known as V(D)J recombination. The process of somatic V(D)J recombination, mediated by the recombination-activating gene (RAG) products, is the most significant characteristic of adaptive immunity in jawed vertebrates. Flounder (Paralichthys olivaceus) RAG1 and RAG2 were isolated by Genome Walker and RT-PCR, and their expression patterns were analysed by RT-PCR and in situ hybridization on sections. RAG1 spans over 7.0 kb, containing 4 exons and 3 introns, and the full-length ORF is 3207 bp, encoding a peptide of 1068 amino acids. The first exon lies in the 5′-UTR, which is an alternative exon. RAG2 full-length ORF is 1062 bp, encodes a peptide of 533 amino acids, and lacks introns in the coding region. In 6-month-old flounders, the expression of RAG1 and RAG2 was essentially restricted to the pronephros (head kidney) and mesonephros (truck kidney). Additionally, both of them were mainly expressed in the thymus. These results revealed that the thymus and kidney most likely serve as the primary lymphoid tissues in the flounder.

  18. Desorption From Interstellar Ices

    CERN Document Server

    Roberts, J F; Viti, S; Williams, D A

    2007-01-01

    The desorption of molecular species from ice mantles back into the gas phase in molecular clouds results from a variety of very poorly understood processes. We have investigated three mechanisms; desorption resulting from H_2 formation on grains, direct cosmic ray heating and cosmic ray induced photodesorption. Whilst qualitative differences exist between these processes (essentially deriving from the assumptions concerning the species-selectivity of the desorption and the assumed threshold adsorption energies, E_t) all three processes are found to be potentially very significant in dark cloud conditions. It is therefore important that all three mechanisms should be considered in studies of molecular clouds in which freeze-out and desorption are believed to be important. Employing a chemical model of a typical static molecular core and using likely estimates for the quantum yields of the three processes we find that desorption by H_2 formation probably dominates over the other two mechanisms. However, the phy...

  19. Evolution of class switch recombination function in fish activation-induced cytidine deaminase, AID.

    Science.gov (United States)

    Wakae, Koshou; Magor, Brad G; Saunders, Holly; Nagaoka, Hitoshi; Kawamura, Akemi; Kinoshita, Kazuo; Honjo, Tasuku; Muramatsu, Masamichi

    2006-01-01

    Following activation of mammalian B cells, class switch recombination (CSR) and somatic hypermutation (SHM) of the Ig heavy chain (IgH) gene can improve the functions of the expressed antibodies. Activation-induced cytidine deaminase (AID) is the only known B cell-specific protein required for inducing CSR and SHM in mammals. Lower vertebrates have an AID homologue, and there is some evidence of SHM in vivo. However there is no evidence of CSR in the cartilaginous or bony fishes, and this may be due in part to a lack of cis-elements in the IgH gene that are the normal targets of AID-mediated recombination. We have tested whether bony fish (zebrafish and catfish) AID can mediate CSR and SHM in mammalian cells. As expected, ectopic expression of fish AID in mouse fibroblasts resulted in mutations in an introduced SHM reporter gene, indicating that fish AID can mediate SHM. Unexpectedly, expression of fish AID in mouse AID-/- B cells induced surface IgG expression as well as switched transcripts from Ig gene loci, clearly indicating that the fish AID protein can mediate CSR, at least in mouse cells. These results suggest that the AID protein acquired the ability to mediate CSR before the IgH locus evolved the additional exon clusters and switch regions that are the targets of recombination. We discuss how pleiotropic functions of specific domains within the AID protein may have facilitated the early evolution of CSR in lower vertebrates.

  20. Construction and expression of a recombinant antibody-targeted plasminogen activator

    International Nuclear Information System (INIS)

    Covalent linkage of tissue-type plasminogen activator (t-PA) to a monoclonal antibody specific for the fibrin β chain (anti-fibrin 59D8) results in a thrombolytic agent that is more specific and more potent that t-PA alone. To provide a ready source of this hybrid molecule and to allow tailoring of the active moieties for optimal activity, the authors have engineered a recombinant version of the 59D8-t-PA conjugate. The rearranged 59D8 heavy chain gene was cloned and combined in the expression vector pSV2gpt with sequence coding for a portion of the γ2b constant region and the catalytic β chain of t-PA. This construct was transfected into heavy chain loss variant cells derived form the 59D8 hybridoma. Recombinant protein was purified by affinity chromatography and analyzed with electrophoretic transfer blots and radioimmunoassay. These revealed a 65-kDa heavy chain-t-PA fusion protein that is secreted in association with the 59D8 light chain in the form of a 170-kDa disulfide-linked dimer. Chromogenic substrate assays showed the fusion protein to have 70% of the peptidolytic activity of native t-PA and to activate plasminogen as efficiently as t-PA. IN a competitive binding assay, reconstituted antibody was shown to have a binding profile similar to that of native 59D8. Thus, by recombinant techniques, they have produced a hybrid protein capable of high affinity fibrin binding and plasminogen activation

  1. Activation and block of recombinant GABAA receptors by pentobarbitone: a single-channel study

    OpenAIRE

    Akk, Gustav; Steinbach, Joe Henry

    2000-01-01

    Recombinant GABAA receptors (α1β2γ2L) were transiently expressed in HEK 293 cells. We have investigated activation and block of these receptors by pentobarbitone (PB) using cell-attached single-channel patch clamp.Clusters of single-channel activity elicited by 500 μM PB were analysed to estimate rate constants for agonist binding and channel gating. The minimal model able to describe the kinetic data involved two sequential binding steps, followed by channel opening. The estimated channel op...

  2. Refolding Techniques for Recovering Biologically Active Recombinant Proteins from Inclusion Bodies

    Directory of Open Access Journals (Sweden)

    Hiroshi Yamaguchi

    2014-02-01

    Full Text Available Biologically active proteins are useful for studying the biological functions of genes and for the development of therapeutic drugs and biomaterials in a biotechnology industry. Overexpression of recombinant proteins in bacteria, such as Escherichia coli, often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. As inclusion bodies contain relatively pure and intact proteins, protein refolding is an important process to obtain active recombinant proteins from inclusion bodies. However, conventional refolding methods, such as dialysis and dilution, are time consuming and, often, recovered yields of active proteins are low, and a trial-and-error process is required to achieve success. Recently, several approaches have been reported to refold these aggregated proteins into an active form. The strategies largely aim at reducing protein aggregation during the refolding procedure. This review focuses on protein refolding techniques using chemical additives and laminar flow in microfluidic chips for the efficient recovery of active proteins from inclusion bodies.

  3. ATM increases activation-induced cytidine deaminase activity at downstream S regions during class-switch recombination.

    Science.gov (United States)

    Khair, Lyne; Guikema, Jeroen E J; Linehan, Erin K; Ucher, Anna J; Leus, Niek G J; Ogilvie, Colin; Lou, Zhenkun; Schrader, Carol E; Stavnezer, Janet

    2014-05-15

    Activation-induced cytidine deaminase (AID) initiates Ab class-switch recombination (CSR) in activated B cells resulting in exchanging the IgH C region and improved Ab effector function. During CSR, AID instigates DNA double-strand break (DSB) formation in switch (S) regions located upstream of C region genes. DSBs are necessary for CSR, but improper regulation of DSBs can lead to chromosomal translocations that can result in B cell lymphoma. The protein kinase ataxia telangiectasia mutated (ATM) is an important proximal regulator of the DNA damage response (DDR), and translocations involving S regions are increased in its absence. ATM phosphorylates H2AX, which recruits other DNA damage response (DDR) proteins, including mediator of DNA damage checkpoint 1 (Mdc1) and p53 binding protein 1 (53BP1), to sites of DNA damage. As these DDR proteins all function to promote repair and recombination of DSBs during CSR, we examined whether mouse splenic B cells deficient in these proteins would show alterations in S region DSBs when undergoing CSR. We find that in atm(-/-) cells Sμ DSBs are increased, whereas DSBs in downstream Sγ regions are decreased. We also find that mutations in the unrearranged Sγ3 segment are reduced in atm(-/-) cells. Our data suggest that ATM increases AID targeting and activity at downstream acceptor S regions during CSR and that in atm(-/-) cells Sμ DSBs accumulate as they lack a recombination partner. PMID:24729610

  4. Complement receptor activity of recombinant porcine CR1-like protein expressed in a eukaryotic system.

    Science.gov (United States)

    Yin, Wei; Wei, Xiaoming; Jiang, Junbing; Fan, Kuohai; Zhao, Junxing; Sun, Na; Wang, Zhiwei; Sun, Yaogui; Ma, Haili; Zhao, Xin; Li, Hongquan

    2016-08-01

    Primate complement receptor type 1 (CR1) protein, a single-chain transmembrane glycoprotein, plays an important role in immune adherence and clearing complement-opsonized immune complexes. Here, the mRNA of the porcine primate-like complement receptor (CR1-like) gene was analyzed, and two domain sequences with potential functions were cloned into the pwPICZalpha vector for expression in Pichia pastoris. The recombinant proteins were purified with both Protein Pure Ni-NTA resin and strong anion exchange resin. The activities of the purified recombinant proteins were evaluated by SDS-PAGE, western blotting, and complement receptor assays. The results indicated that two domains of the CR1-like protein, CCP36 and CCP811 with molecular weights of 29.8 kDa and 30 kDa, respectively, were successfully expressed in P. pastoris. These two recombinant proteins possess some of the functions of the primate CR1 protein. Using these two proteins coupled with an antibody blocking technique, we also showed that CR1-like is expressed on natural porcine erythrocytes. PMID:26903010

  5. Discovery of an Active RAG Transposon Illuminates the Origins of V(D)J Recombination.

    Science.gov (United States)

    Huang, Shengfeng; Tao, Xin; Yuan, Shaochun; Zhang, Yuhang; Li, Peiyi; Beilinson, Helen A; Zhang, Ya; Yu, Wenjuan; Pontarotti, Pierre; Escriva, Hector; Le Petillon, Yann; Liu, Xiaolong; Chen, Shangwu; Schatz, David G; Xu, Anlong

    2016-06-30

    Co-option of RAG1 and RAG2 for antigen receptor gene assembly by V(D)J recombination was a crucial event in the evolution of jawed vertebrate adaptive immunity. RAG1/2 are proposed to have arisen from a transposable element, but definitive evidence for this is lacking. Here, we report the discovery of ProtoRAG, a DNA transposon family from lancelets, the most basal extant chordates. A typical ProtoRAG is flanked by 5-bp target site duplications and a pair of terminal inverted repeats (TIRs) resembling V(D)J recombination signal sequences. Between the TIRs reside tail-to-tail-oriented, intron-containing RAG1-like and RAG2-like genes. We demonstrate that ProtoRAG was recently active in the lancelet germline and that the lancelet RAG1/2-like proteins can mediate TIR-dependent transposon excision, host DNA recombination, transposition, and low-efficiency TIR rejoining using reaction mechanisms similar to those used by vertebrate RAGs. We propose that ProtoRAG represents a molecular "living fossil" of the long-sought RAG transposon. PMID:27293192

  6. Cre-dependent DNA recombination activates a STING-dependent innate immune response.

    Science.gov (United States)

    Pépin, Geneviève; Ferrand, Jonathan; Höning, Klara; Jayasekara, W Samantha N; Cain, Jason E; Behlke, Mark A; Gough, Daniel J; G Williams, Bryan R; Hornung, Veit; Gantier, Michael P

    2016-06-20

    Gene-recombinase technologies, such as Cre/loxP-mediated DNA recombination, are important tools in the study of gene function, but have potential side effects due to damaging activity on DNA. Here we show that DNA recombination by Cre instigates a robust antiviral response in mammalian cells, independent of legitimate loxP recombination. This is due to the recruitment of the cytosolic DNA sensor STING, concurrent with Cre-dependent DNA damage and the accumulation of cytoplasmic DNA. Importantly, we establish a direct interplay between this antiviral response and cell-cell interactions, indicating that low cell densities in vitro could be useful to help mitigate these effects of Cre. Taking into account the wide range of interferon stimulated genes that may be induced by the STING pathway, these results have broad implications in fields such as immunology, cancer biology, metabolism and stem cell research. Further, this study sets a precedent in the field of gene-engineering, possibly applicable to other enzymatic-based genome editing technologies. PMID:27166376

  7. Construction of an oral recombinant DNA vaccine from H pylori neutrophil activating protein and its immunogenicity

    Institute of Scientific and Technical Information of China (English)

    Bo Sun; Zhao-Shen Li; Zhen-Xing Tu; Guo-Ming Xu; Yi-Qi Du

    2006-01-01

    AIM: To construct a live attenuated Salmonella typhimurium (S.typhimurium) strain harboring the H pylori neutrophil activating protein (HP-NAP) gene as an oral recombinant DNA vaccine, and to evaluate its immunogenicity.METHODS: By genetic engineering methods, the genomic DNA of H pylori was extracted as a template. The total length of the HP-NAP gene was amplified by polymerase chain reaction (PCR) and cloned into pBT vector for sequencing and BLAST analysis, then subcloned into a eukaryotic expression vector pIRES followed by PCR identification and restriction enzyme digestion. The identified recombinant plasmid pIRES-NAP was transfected into COS-7 cells for target fusion protein expression, and its antigenicity was detected by Western blotting. Then the recombinant plasmid was transformed into a live attenuated S. typhimurium strain SL7207 as an oral vaccine strain, and its immunogenicity was evaluated with animal experiments.RESULTS: A 435 bp product was cloned using high homology with HP-NAP gene in GenBank (more than 98%). With identification by PCR and restriction enzyme digestion, a recompinant eukaryotic expression plasmid pIRES-NAP containing the HP-NAP gene of H pylori was successfully constructed. The expressed target protein had a specific reaction with H pylor(i) whole cell antibody and showed a single strip result detected by Western blotting. Oral immunization of mice with recombinant DNA vaccine strain SL7207 (pIRES-NAP) also induced a specific immune response.CONCLUSION: The successful construction of HP-NAP oral DNA vaccine with good immunogenicity may help to further investigate its immunoprotection effects and develop vaccine against H pylori infection.

  8. Characterization of the Active Surface Species Responsible for UV-Induced Desorption of O2 from the Rutile TiO2(110) Surface

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, Michael A.; Shen, Mingmin; Wang, Zhitao; Lyubinetsky, Igor

    2013-03-21

    We have examined the chemical and photochemical properties of molecular oxygen on the (110) surface of rutile TiO2 at 100 K using electron energy loss spectroscopy (EELS), photon stimulated desorption (PSD) and scanning tunneling microscopy (STM). Oxygen chemisorbs on the TiO2(110) surface at 100 K through charge transfer from surface Ti3+ sites. The charge transfer process is evident in EELS by a decrease in the intensity of the Ti3+ d-to-d transition in EELS at ~0.9 eV and formation of a new loss ~2.8 eV. Based on comparisons with the available homogeneous and heterogeneous literature for complexed/adsorbed O2, the species responsible for the 2.8 eV peak can be assigned to a surface peroxo (O2 2-) state of O2. This species was identified as the active form of adsorbed O2 on TiO2(110) for PSD. The adsorption site of this peroxo species was assigned to that of a regular five-cooridinated Ti4+ (Ti5c) site based on comparisons between the UV exposure dependent behavior of O2 in STM, PSD and EELS data. Assignment of the active form of adsorbed O2 to a peroxo species at normal Ti5c sites necessitates reevaluation of the simple mechanism in which a single valence band hole neutralizes a singly charged O2 species (superoxo or O2-) leading to desorption of O2 from a physisorbed potential energy surface. This work was supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, and the Chemical Imaging Initiative at Pacific Northwest National Laboratory (PNNL), and was performed in the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE's Office of Biological and Environmental Research and located at PNNL.

  9. Stability of Recombinant Tissue Plasminogen Activator at −30 °C Over One Year

    Science.gov (United States)

    Alkatheri, Abdulmalik

    2012-01-01

    Recombinant tissue plasminogen activator (rt-PA) is used to restore patency and avoid inadvertent removal of peripheral and central venous catheters. rt-PA was reconstituted (1 mg/mL) then cryopreserved at −30 °C for 1, 2, 3, 6, 8, and 12 months and, then its stability was determined. After cryopreservation for one and two months, rt-PA kept more than 95% of its activity compared to standard samples, while cryopreservation for three months caused 8% loss of activity. However, after cryopreservation for six months or more, rt-PA retained only 87.5% or less activity compared to standard samples. Therefore, it is recommended that reconstituted rt-PA be cryopreserved at −30 °C for a maximum period of three months. PMID:24275785

  10. Does intravenous administration of recombinant tissue plasminogen activator for ischemic stroke can cause inferior myocardial infarction?

    Directory of Open Access Journals (Sweden)

    Mostafa Almasi

    2016-06-01

    Full Text Available Recombinant tissue plasminogen activator (rTPA is one of the main portions of acute ischemic stroke management, but unfortunately has some complications. Myocardial infarction (MI is a hazardous complication of administration of intravenous rTPA that has been reported recently. A 78-year-old lady was admitted for elective coronary artery bypass graft surgery. On the second day of admission, she developed acute left hemiparesis and intravenous rTPA was administered within 120 minutes. Three hours later, she has had chest pain. Rescue percutaneous coronary intervention was performed on right coronary artery due to diagnosis of inferior MI, and the symptoms were resolved.

  11. Expression, Purification and Activity Assay of Two New Recombinant Antagonists of Fibrinogen Receptor

    Directory of Open Access Journals (Sweden)

    Jianbo Yang

    2005-01-01

    Full Text Available The gene sequence of Decorsin which is extracted from a kind of North American leeches was synthesized. Two recombinant proteins, Annexin V plus Decorsin (AnnV-D39 and Annexin V plus the carboxyl terminal 27 amino acid residues of Decorsin(AnnV-D27, were constructed. And a 10 amino acids linker peptide of GGGGSGGGGS was inserted between Annexin V and Decorsin in AnnV-D39. Using pET-28(a+ as an expressing vector, both two recombinant proteins were expressed in E. Coli BL21(DE3 with high efficiency as inclusion bodies. The expression products were purified by DEAE-Cellulose 52 and Sepharose CL-4B chromatography under denaturing condition. Platelet Aggregation Assay (PAA shows that AnnV-D39 has good anti-platelet aggregation activity. However, AnnV-D27 shows no such activities in any PAA test. AnnV-D39 shows good anti-platelet aggregation activity as a new antagonist of fibrinogen receptor, while Annv-D27 needs re-modification

  12. A Butter Aroma Recombinate Activates Human Class-I Odorant Receptors.

    Science.gov (United States)

    Geithe, Christiane; Andersen, Gaby; Malki, Agne; Krautwurst, Dietmar

    2015-11-01

    With ∼400 olfactory G protein-coupled receptors (GPCR), humans sensitively perceive ∼230 key aroma compounds as best natural agonists of ∼10000 food volatiles. An understanding of odorant coding, thus, critically depends on the knowledge about interactions of key food aroma chemicals and their mixtures with their cognate receptors. Genetically designed test cell systems enable the screening, deorphaning, and characterization of single odorant receptors (OR). This study shows for the food aroma-specific and quantitative butter aroma recombinate, and its single components, specific in vitro class-I OR activity patterns, as well as the activation of selected OR in a concentration-dependent manner. Recently, chemosensory receptors, especially class-I OR, were demonstrated to be expressed on blood leukocytes, which may encounter foodborne aroma compounds postprandially. This study shows that butter aroma recombinate induced chemotaxis of isolated human neutrophils in a defined gradient, and in a concentration-dependent and pertussis toxin-sensitive manner, suggesting at least a GPCR-mediated activation of blood leukocytes by key food odorants.

  13. The Meiotic Recombination Activator PRDM9 Trimethylates Both H3K36 and H3K4 at Recombination Hotspots In Vivo.

    Science.gov (United States)

    Powers, Natalie R; Parvanov, Emil D; Baker, Christopher L; Walker, Michael; Petkov, Petko M; Paigen, Kenneth

    2016-06-01

    In many mammals, including humans and mice, the zinc finger histone methyltransferase PRDM9 performs the first step in meiotic recombination by specifying the locations of hotspots, the sites of genetic recombination. PRDM9 binds to DNA at hotspots through its zinc finger domain and activates recombination by trimethylating histone H3K4 on adjacent nucleosomes through its PR/SET domain. Recently, the isolated PR/SET domain of PRDM9 was shown capable of also trimethylating H3K36 in vitro, raising the question of whether this reaction occurs in vivo during meiosis, and if so, what its function might be. Here, we show that full-length PRDM9 does trimethylate H3K36 in vivo in mouse spermatocytes. Levels of H3K4me3 and H3K36me3 are highly correlated at hotspots, but mutually exclusive elsewhere. In vitro, we find that although PRDM9 trimethylates H3K36 much more slowly than it does H3K4, PRDM9 is capable of placing both marks on the same histone molecules. In accord with these results, we also show that PRDM9 can trimethylate both K4 and K36 on the same nucleosomes in vivo, but the ratio of K4me3/K36me3 is much higher for the pair of nucleosomes adjacent to the PRDM9 binding site compared to the next pair further away. Importantly, H3K4me3/H3K36me3-double-positive nucleosomes occur only in regions of recombination: hotspots and the pseudoautosomal (PAR) region of the sex chromosomes. These double-positive nucleosomes are dramatically reduced when PRDM9 is absent, showing that this signature is PRDM9-dependent at hotspots; the residual double-positive nucleosomes most likely come from the PRDM9-independent PAR. These results, together with the fact that PRDM9 is the only known mammalian histone methyltransferase with both H3K4 and H3K36 trimethylation activity, suggest that trimethylation of H3K36 plays an important role in the recombination process. Given the known requirement of H3K36me3 for double strand break repair by homologous recombination in somatic cells, we

  14. Characterization and immunological activity of different forms of recombinant secreted Hc of botulinum neurotoxin serotype B products expressed in yeast

    OpenAIRE

    Liu, Bo; Shi, DanYang; Chang, Shaohong; Gong, Xin; Yu, YunZhou; Sun, Zhiwei; Wu, Jun

    2015-01-01

    The recombinant Hc proteins of botulinum neurotoxins and tetanus toxin are exclusively produced by intracellular heterologous expression in Pichia pastoris for use in subunit vaccines; the same Hc proteins produced by secreted heterologous expression are hyper-glycosylated and immunologically inert. Here, several different recombinant secreted Hc proteins of botulinum neurotoxin serotype B (BHc) were expressed in yeast and we characterized and assessed their immunological activity in detail. ...

  15. Albinism-causing mutations in recombinant human tyrosinase alter intrinsic enzymatic activity.

    Directory of Open Access Journals (Sweden)

    Monika B Dolinska

    Full Text Available BACKGROUND: Tyrosinase (TYR catalyzes the rate-limiting, first step in melanin production and its gene (TYR is mutated in many cases of oculocutaneous albinism (OCA1, an autosomal recessive cause of childhood blindness. Patients with reduced TYR activity are classified as OCA1B; some OCA1B mutations are temperature-sensitive. Therapeutic research for OCA1 has been hampered, in part, by the absence of purified, active, recombinant wild-type and mutant human enzymes. METHODOLOGY/PRINCIPAL FINDINGS: The intra-melanosomal domain of human tyrosinase (residues 19-469 and two OCA1B related temperature-sensitive mutants, R422Q and R422W were expressed in insect cells and produced in T. ni larvae. The short trans-membrane fragment was deleted to avoid potential protein insolubility, while preserving all other functional features of the enzymes. Purified tyrosinase was obtained with a yield of >1 mg per 10 g of larval biomass. The protein was a monomeric glycoenzyme with maximum enzyme activity at 37°C and neutral pH. The two purified mutants when compared to the wild-type protein were less active and temperature sensitive. These differences are associated with conformational perturbations in secondary structure. CONCLUSIONS/SIGNIFICANCE: The intramelanosomal domains of recombinant wild-type and mutant human tyrosinases are soluble monomeric glycoproteins with activities which mirror their in vivo function. This advance allows for the structure - function analyses of different mutant TYR proteins and correlation with their corresponding human phenotypes; it also provides an important tool to discover drugs that may improve tyrosinase activity and treat OCA1.

  16. Activity and stability of recombinant human superoxide dismutase in buffer solutions and hypothermic perfusates.

    Directory of Open Access Journals (Sweden)

    Senoo,Yoshimasa

    1988-06-01

    Full Text Available The stability of recombinant human superoxide dismutase (r-hSOD in buffer solutions was studied in solutions at various pH and temperatures. Additionally, we studied the effects of incubation with proteases, serum and two types of hypothermic perfusates. R-hSOD was stable in the pH range of 6-11 and at temperatures up to 80 degrees C for 30 min. R-hSOD activity was not affected by incubation with trypsin, aminopeptidase M or serum for 2 h. R-hSOD activity determined at various temperatures (4-37 degrees C did not vary remarkably. R-hSOD in hypothermic perfusates was stable at 4-37 degrees C for 24 h.

  17. Recombinant human diamine oxidase activity is not inhibited by ethanol, acetaldehyde, disulfiram, diethyldithiocarbamate or cyanamide.

    Science.gov (United States)

    Bartko, Johann; Gludovacz, Elisabeth; Petroczi, Karin; Borth, Nicole; Jilma, Bernd; Boehm, Thomas

    2016-08-01

    Human diamine oxidase (hDAO, EC 1.4.3.22) is the key enzyme in the degradation of extracellular histamine. Consumption of alcohol is a known trigger of mast cell degranulation in patients with mast cell activation syndrome. Ethanol may also interfere with enzymatic histamine degradation, but reports on the effects on DAO activity are controversial. There are also conflicting reports whether disulfiram, an FDA-approved agent in the treatment of alcohol dependence, inhibits DAO. We therefore investigated the inhibitory potential of ethanol and disulfiram and their metabolites on recombinant human DAO (rhDAO) in three different assay systems. Relevant concentrations of ethanol, acetaldehyde, and acetate did not inhibit rhDAO activity in an in vitro assay system using horseradish peroxidase (HRP) -mediated luminol oxidation. The aldehyde dehydrogenase (ALDH; EC 1.2.1.3) inhibitors cyanamide and its dimer dicyanamide also had no effect on DAO activity. In one assay system, the irreversible ALDH inhibitor disulfiram and its main metabolite diethyldithiocarbamate seemed to inhibit DAO activity. However, the decreased product formation was not due to a direct block of DAO activity but resulted from inhibition of peroxidase employed in the coupled system. Our in vitro data do not support a direct blocking effect of ethanol, disulfiram, and their metabolites on DAO activity in vivo. PMID:27401969

  18. Correlation between the glycan variations and defibrinogenating activities of acutobin and its recombinant glycoforms.

    Directory of Open Access Journals (Sweden)

    Ying-Ming Wang

    Full Text Available Acutobin isolated from Deinagkistrodon acutus venom has been used to prevent or treat stroke in patients. This defibrinogenating serine protease is a 39 kDa glycoprotein containing terminal disialyl-capped N-glycans. After sialidase treatment, the enzyme showed similar catalytic activities toward chromogenic substrate, and cleaved the Aα chain of fibrinogen as efficiently as the native acutobin did. However, the level of fibrinogen degradation products in mice after i.p.-injection of desialylated-acutobin was significantly lower than the level after acutobin injection, suggesting that the disialyl moieties may improve or prolong the half-life of acutobin. Two recombinant enzymes with identical protein structures and similar amidolytic activities to those of native acutobin were expressed from HEK293T and SW1353 cells and designated as HKATB and SWATB, respectively. Mass spectrometric profiling showed that their glycans differed from those of acutobin. In contrast to acutobin, HKATB cleaved not only the Aα chain but also the Bβ and γ chains of human fibrinogens, while SWATB showed a reduced α-fibrinogenase activity. Non-denaturing deglycosylation of these proteases by peptide N-glycosidase F significantly reduced their fibrinogenolytic activities and thermal stabilities. The in vivo defibrinogenating effect of HKATB was inferior to that of acutobin in mice. Taken together, our results suggest that the conjugated glycans of acutobin are involved in its interaction with fibrinogen, and that the selection of cells optimally expressing efficient glycoforms and further glycosylation engineering are desirable before a recombinant product can replace the native enzyme for clinical use.

  19. Perlecan domain 1 recombinant proteoglycan augments BMP-2 activity and osteogenesis

    Directory of Open Access Journals (Sweden)

    DeCarlo Arthur A

    2012-09-01

    Full Text Available Abstract Background Many growth factors, such as bone morphogenetic protein (BMP-2, have been shown to interact with polymers of sulfated disacharrides known as heparan sulfate (HS glycosaminoglycans (GAGs, which are found on matrix and cell-surface proteoglycans throughout the body. HS GAGs, and some more highly sulfated forms of chondroitin sulfate (CS, regulate cell function by serving as co-factors, or co-receptors, in GF interactions with their receptors, and HS or CS GAGs have been shown to be necessary for inducing signaling and GF activity, even in the osteogenic lineage. Unlike recombinant proteins, however, HS and CS GAGs are quite heterogenous due, in large part, to post-translational addition, then removal, of sulfate groups to various positions along the GAG polymer. We have, therefore, investigated whether it would be feasible to deliver a DNA pro-drug to generate a soluble HS/CS proteoglycan in situ that would augment the activity of growth-factors, including BMP-2, in vivo. Results Utilizing a purified recombinant human perlecan domain 1 (rhPln.D1 expressed from HEK 293 cells with HS and CS GAGs, tight binding and dose-enhancement of rhBMP-2 activity was demonstrated in vitro. In vitro, the expressed rhPln.D1 was characterized by modification with sulfated HS and CS GAGs. Dose-enhancement of rhBMP-2 by a pln.D1 expression plasmid delivered together as a lyophilized single-phase on a particulate tricalcium phosphate scaffold for 6 or more weeks generated up to 9 fold more bone volume de novo on the maxillary ridge in a rat model than in control sites without the pln.D1 plasmid. Using a significantly lower BMP-2 dose, this combination provided more than 5 times as much maxillary ridge augmentation and greater density than rhBMP-2 delivered on a collagen sponge (InFuse™. Conclusions A recombinant HS/CS PG interacted strongly and functionally with BMP-2 in binding and cell-based assays, and, in vivo, the pln.247 expression plasmid

  20. Generation of biologically active multi-sialylated recombinant human EPOFc in plants.

    Directory of Open Access Journals (Sweden)

    Alexandra Castilho

    Full Text Available Hyperglycosylated proteins are more stable, show increased serum half-life and less sensitivity to proteolysis compared to non-sialylated forms. This applies particularly to recombinant human erythropoietin (rhEPO. Recent progress in N-glycoengineering of non-mammalian expression hosts resulted in in vivo protein sialylation at great homogeneity. However the synthesis of multi-sialylated N-glycans is so far restricted to mammalian cells. Here we used a plant based expression system to accomplish multi-antennary protein sialylation. A human erythropoietin fusion protein (EPOFc was transiently expressed in Nicotiana benthamiana ΔXTFT, a glycosylation mutant that lacks plant specific N-glycan residues. cDNA of the hormone was co-delivered into plants with the necessary genes for (i branching (ii β1,4-galactosylation as well as for the (iii synthesis, transport and transfer of sialic acid. This resulted in the production of recombinant EPOFc carrying bi- tri- and tetra-sialylated complex N-glycans. The formation of this highly complex oligosaccharide structure required the coordinated expression of 11 human proteins acting in different subcellular compartments at different stages of the glycosylation pathway. In vitro receptor binding assays demonstrate the generation of biologically active molecules. We demonstrate the in planta synthesis of one of the most complex mammalian glycoforms pointing to an outstanding high degree of tolerance to changes in the glycosylation pathway in plants.

  1. Residual endotoxin contaminations in recombinant proteins are sufficient to activate human CD1c+ dendritic cells.

    Directory of Open Access Journals (Sweden)

    Harald Schwarz

    Full Text Available Many commercially available recombinant proteins are produced in Escherichia coli, and most suppliers guarantee contamination levels of less than 1 endotoxin unit (EU. When we analysed commercially available proteins for their endotoxin content, we found contamination levels in the same range as generally stated in the data sheets, but also some that were higher. To analyse whether these low levels of contamination have an effect on immune cells, we stimulated the monocytic cell line THP-1, primary human monocytes, in vitro differentiated human monocyte-derived dendritic cells, and primary human CD1c+ dendritic cells (DCs with very low concentrations of lipopolysaccharide (LPS; ranging from 0.002-2 ng/ml. We show that CD1c+ DCs especially can be activated by minimal amounts of LPS, equivalent to the levels of endotoxin contamination we detected in some commercially available proteins. Notably, the enhanced endotoxin sensitivity of CD1c+ DCs was closely correlated with high CD14 expression levels observed in CD1c+ DCs that had been maintained in cell culture medium for 24 hours. When working with cells that are particularly sensitive to LPS, even low endotoxin contamination may generate erroneous data. We therefore recommend that recombinant proteins be thoroughly screened for endotoxin contamination using the limulus amebocyte lysate test, fluorescence-based assays, or a luciferase based NF-κB reporter assay involving highly LPS-sensitive cells overexpressing TLR4, MD-2 and CD14.

  2. Inhibition of activated protein C by recombinant alpha 1-antitrypsin variants with substitution of arginine or leucine for methionine358

    NARCIS (Netherlands)

    Heeb, M.J.; Bischoff, Rainer; Courtney, M.; Griffin, J.H.

    1990-01-01

    alpha 1-Antitrypsin (alpha 1-AT) was recently identified as a major physiologic plasma inhibitor of activated protein C. The reaction with activated protein C of recombinant alpha 1-AT containing amino acid substitutions at the reactive center was studied. The substitution of Arg358 for Met, as obse

  3. Effect of haemodilution, acidosis, and hypothermia on the activity of recombinant factor VIIa (NovoSeven)

    DEFF Research Database (Denmark)

    Viuff, D.; Lauritzen, B.; Pusateri, A.E.;

    2008-01-01

    BACKGROUND: A range of plasma volume expanders is used clinically, often in settings where haemostasis may already be impaired. The haemostatic agent, recombinant activated factor VII (rFVIIa, NovoSeven), may be used to improve haemostasis but potential interactions with different volume expanders......%, or hydroxyethyl starch (HES) solutions [MW (molecular weight) 130-670 kDa]; by adjusting pH to 6.8 with 1 M HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulphonic acid) buffer; or by reducing temperature to 32 degrees C. We also studied the effect of low vs high MW HES (MW 200 vs 600 kDa) and rFVIIa on in vivo...

  4. Tankyrases Promote Homologous Recombination and Check Point Activation in Response to DSBs.

    Directory of Open Access Journals (Sweden)

    Zita Nagy

    2016-02-01

    Full Text Available DNA lesions are sensed by a network of proteins that trigger the DNA damage response (DDR, a signaling cascade that acts to delay cell cycle progression and initiate DNA repair. The Mediator of DNA damage Checkpoint protein 1 (MDC1 is essential for spreading of the DDR signaling on chromatin surrounding Double Strand Breaks (DSBs by acting as a scaffold for PI3K kinases and for ubiquitin ligases. MDC1 also plays a role both in Non-Homologous End Joining (NHEJ and Homologous Recombination (HR repair pathways. Here we identify two novel binding partners of MDC1, the poly (ADP-ribose Polymerases (PARPs TNKS1 and 2. We find that TNKSs are recruited to DNA lesions by MDC1 and regulate DNA end resection and BRCA1A complex stabilization at lesions leading to efficient DSB repair by HR and proper checkpoint activation.

  5. Tankyrases Promote Homologous Recombination and Check Point Activation in Response to DSBs.

    Science.gov (United States)

    Nagy, Zita; Kalousi, Alkmini; Furst, Audrey; Koch, Marc; Fischer, Benoit; Soutoglou, Evi

    2016-02-01

    DNA lesions are sensed by a network of proteins that trigger the DNA damage response (DDR), a signaling cascade that acts to delay cell cycle progression and initiate DNA repair. The Mediator of DNA damage Checkpoint protein 1 (MDC1) is essential for spreading of the DDR signaling on chromatin surrounding Double Strand Breaks (DSBs) by acting as a scaffold for PI3K kinases and for ubiquitin ligases. MDC1 also plays a role both in Non-Homologous End Joining (NHEJ) and Homologous Recombination (HR) repair pathways. Here we identify two novel binding partners of MDC1, the poly (ADP-ribose) Polymerases (PARPs) TNKS1 and 2. We find that TNKSs are recruited to DNA lesions by MDC1 and regulate DNA end resection and BRCA1A complex stabilization at lesions leading to efficient DSB repair by HR and proper checkpoint activation. PMID:26845027

  6. Tankyrases Promote Homologous Recombination and Check Point Activation in Response to DSBs

    Science.gov (United States)

    Furst, Audrey; Koch, Marc; Fischer, Benoit; Soutoglou, Evi

    2016-01-01

    DNA lesions are sensed by a network of proteins that trigger the DNA damage response (DDR), a signaling cascade that acts to delay cell cycle progression and initiate DNA repair. The Mediator of DNA damage Checkpoint protein 1 (MDC1) is essential for spreading of the DDR signaling on chromatin surrounding Double Strand Breaks (DSBs) by acting as a scaffold for PI3K kinases and for ubiquitin ligases. MDC1 also plays a role both in Non-Homologous End Joining (NHEJ) and Homologous Recombination (HR) repair pathways. Here we identify two novel binding partners of MDC1, the poly (ADP-ribose) Polymerases (PARPs) TNKS1 and 2. We find that TNKSs are recruited to DNA lesions by MDC1 and regulate DNA end resection and BRCA1A complex stabilization at lesions leading to efficient DSB repair by HR and proper checkpoint activation. PMID:26845027

  7. Annealing effects on recombinative activity of nickel at direct silicon bonded interface

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Takuto, E-mail: tkojima@toyota-ti.ac.jp; Ohshita, Yoshio; Yamaguchi, Masafumi [Toyota Technological Institute, 2-12-1 Hisakata, Tempaku-ku, Nagoya, 468-8511 (Japan)

    2015-09-15

    By performing capacitance transient analyses, the recombination activity at a (110)/(100) direct silicon bonded (DSB) interface contaminated with nickel diffused at different temperatures, as a model of grain boundaries in multicrystalline silicon, was studied. The trap level depth from the valence band, trap density of states, and hole capture cross section peaked at an annealing temperature of 300 °C. At temperatures ⩾400 °C, the hole capture cross section increased with temperature, but the density of states remained unchanged. Further, synchrotron-based X-ray analyses, microprobe X-ray fluorescence (μ-XRF), and X-ray absorption near edge structure (XANES) analyses were performed. The analysis results indicated that the chemical phase after the sample was annealed at 200 °C was a mixture of NiO and NiSi{sub 2}.

  8. Failure of Recombinant Activated Factor VII in Treatment of Diffuse Alveolar Hemorrhage due to Cryoglobulinemic Vasculitis

    Directory of Open Access Journals (Sweden)

    Dania Khoulani

    2014-01-01

    Full Text Available Diffuse alveolar hemorrhage (DAH is a serious complication of the small vessel vasculitis syndromes and carries a high mortality. Recombinant activated factor VII (rFVIIa is used to treat bleeding in patients with hemophilia and antibodies to factor VIII or IX. It is increasingly being used in life-threatening hemorrhage in a variety of other settings in which conventional therapy is unsuccessful. Randomized controlled trials of rFVIIa in DAH are lacking. However, several case reports have described a complete or sustained control of DAH using rFVIIa after patients failed to respond to medical treatment. There are no case reports in the literature describing the use or the failure of rFVIIa in DAH associated with cryoglobulinemic vasculitis. We here report the failure of rFVIIa to control DAH in a patient with CD5+ B-cell non-Hodgkin’s lymphoma and cryoglobulinemic vasculitis.

  9. Recombinant activated factor Ⅶ in hemophagocytic lymphohistiocytosis with disseminated intravascular coagulation

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Jun-ling; JIANG Qing-wei; XU Ying; WANG Shu-jie

    2011-01-01

    Hemophagocytic lymphohistiocytosis (HLH) is a lifethreatening disorder due to hyperinflammation resulting in infiltration of different organs with extensive hemophagocytosis. Severe coagulopathy was one of the main reasons for death in HLH. Over secretion of plasminogen activator by activated macrophages leads to hyperfibrinolysis. We reported a 36-year-old woman who was diagnosed as HLH probably secondary to lymphoma. Massive bleeding from gut and retroperitoneal area were not able to be controlled by conventional hemostatic treatments. This patient received one dose recombinant activated factor Ⅶ (rFVlla) 3.6 mg (70 μg/kg). Hemostatic effect was achieved in 0.5 hour and lasted 24 hours. Prothrombin time (PT) and activated partial thromboplastin time (APTT) were quickly corrected to normal ranges.Fibrinogen level elevated from 0.5 g/L before using rFVIla to 1.8 g/L 20 hours after. Although dexamethasone and etopside were administrated to treat HLH, this patient died from septic shock after persistent neutropenia. This suggests that rFVlla may be effective in the management of intractable hemorrhage in patients with HLH.

  10. Characterization of indium-111 labeled recombinant tissue plasminogen activator for the imaging of thrombi

    International Nuclear Information System (INIS)

    The in vitro functional properties of recombinant tissue plasminogen activator (rt-PA), its biodistribution in mice, and its pharmacokinetics and clot localization properties in dogs have been investigated after labeling rt-PA with 111In. The rt-PA was coupled with the cyclic anhydride of DTPA using standard methodology. Amidolytic and fibrinolytic assays showed retention of protein activity when rt-PA was conjugated with an average of one DTPA group or less per molecule. Size exclusion HPLC showed each preparation to be radiochemically pure with 111In bound exlusively to the attached DTPA groups. Biodistribution in mice showed major accumulation of activity in the liver and kidneys. After administration of 0.5-1.0 mg of the labeled protein to dogs, blood activity decreased with a half time of approximately 5 min in agreement with previous reports of rapid blood clearance. Largely because of decreased blood levels, clot:blood ratios of labeled protein increased rapidly, in one study reaching 6.3 after 31 min, and satisfactory images of fibrin thrombi were obtained. The rt-PA may be labeled with 111In without destroying the ability of the protein to loacalize n clot and images of forming clot can be obtained with this agent within 1 h after administration. (orig.)

  11. Bimolecular recombination reactions: K-adiabatic and K-active forms of the bimolecular master equations and analytic solutions

    Science.gov (United States)

    Ghaderi, Nima

    2016-03-01

    Expressions for a K-adiabatic master equation for a bimolecular recombination rate constant krec are derived for a bimolecular reaction forming a complex with a single well or complexes with multiple well, where K is the component of the total angular momentum along the axis of least moment of inertia of the recombination product. The K-active master equation is also considered. The exact analytic solutions, i.e., the K-adiabatic and K-active steady-state population distribution function of reactive complexes, g(EJK) and g(EJ), respectively, are derived for the K-adiabatic and K-active master equation cases using properties of inhomogeneous integral equations (Fredholm type). The solutions accommodate arbitrary intermolecular energy transfer models, e.g., the single exponential, double exponential, Gaussian, step-ladder, and near-singularity models. At the high pressure limit, the krec for both the K-adiabatic and K-active master equations reduce, respectively, to the K-adiabatic and K-active bimolecular Rice-Ramsperger-Kassel-Marcus theory (high pressure limit expressions). Ozone and its formation from O + O2 are known to exhibit an adiabatic K. The ratio of the K-adiabatic to the K-active recombination rate constants for ozone formation at the high pressure limit is calculated to be ˜0.9 at 300 K. Results on the temperature and pressure dependence of the recombination rate constants and populations of O3 will be presented elsewhere.

  12. Vaccinia virus recombinants expressing an 11-kilodalton beta-galactosidase fusion protein incorporate active beta-galactosidase in virus particles.

    Science.gov (United States)

    Huang, C; Samsonoff, W A; Grzelecki, A

    1988-10-01

    Recombinant plasmids in which vaccinia virus transcriptional regulatory sequences were fused to the Escherichia coli lacZ gene were constructed for insertion of the lacZ gene into the vaccinia virus genome. beta-Galactosidase (beta-gal) was found in some purified recombinant vaccinia virions. By enzyme activity, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and microscopic techniques, the evidence suggested that beta-gal accounted for 5% of the total protein in the virion. These recombinant viruses were constructed so that a portion of the coding sequences of a late vaccinia virus structural polypeptide was fused to the amino terminus of beta-gal to produce the fusion protein. Removal of the coding sequences resulted in the complete loss of beta-gal activity. This demonstrated that a vaccinia virus DNA segment from a late structural gene is responsible for the incorporation of beta-gal into the virion.

  13. A macroporous bioreactor super activated by the recombinant human transforming growth factor-beta 3

    Directory of Open Access Journals (Sweden)

    Ugo eRipamonti

    2012-06-01

    Full Text Available Macroporous single-phase hydroxyapatite (HA and biphasic HA/β-tricalcium phosphate with 33% post-sinter hydroxyapatite (HA/β-TCP were combined with 25 or 125 µg recombinant human transforming growth factor-β3 (hTGF-β3 to engineer a super activated bioreactor implanted in orthotopic calvarial and heterotopic rectus abdominis muscle sites and harvested on day 30 and 90. Coral-derived calcium carbonate fully converted (100% and partially converted to 5% and 13% hydroxyapatite/calcium carbonate (HA/CC preloaded with 125 and 250 µg hTGF-β3, and 1:5 and 5:1 binary applications of hTGF-β3: hOP-1 by weight, were implanted in the rectus abdominis and harvested on day 20 and 30, respectively, to monitor spatial/temporal morphogenesis by high doses of hTGF-β3. Bone formation was assessed on decalcified paraffin-embedded sections by measuring the fractional volume of newly-formed bone. On day 30 and 90, single phase HA implants showed greater amounts of bone when compared to biphasic specimens; 5 % and 13 % HA/CC pre-loaded with 125 and 250 µg hTGF-β3 showed substantial induction of bone formation; 250 µg hTGF-β3 induced as yet unreported massive induction of bone formation as early as 20 days prominently outside the profile of the macroporous constructs. The induction of bone formation is controlled by the implanted ratio of the recombinant morphogens, i.e. the 1:5 hTGF-β3:hOP-1 ratio by weight was greater than the inverse ratio. The unprecedented tissue induction by single doses of 250 µg hTGF-β3 resulting in rapid bone morphogenesis of vast mineralized ossicles with multiple trabeculations surfaced by contiguous secreting osteoblasts is the novel molecular and morphological frontier for the induction of bone formation in clinical contexts.

  14. The Helper Activities of Different Avian Viruses for Propagation of Recombinant Avian Adeno-Associated Virus

    Institute of Scientific and Technical Information of China (English)

    WANG An-ping; SUN Huai-chang; WANG Jian-ye; WANG Yong-juan; YUAN Wei-feng

    2007-01-01

    To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus (rAAAV), AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluorescent protein (GFP) gene, the AAAV helper vector pcDNA-ARC expressing the rep and cap genes, and the adenovirus helper vector pHelper expressing Ad5 E2A, E4, and VA-RNA genes. Chicken embryonic fibroblast (CEF) or chicken embryonic liver (CEL) cells were cotransfected with the AAAV vector and the AAAV helper vector, followed by infection with Marek's disease virus (MDV), avian adenovirus, chicken embryo lethal orphan (CELO) virus or infectious bursal disease virus (IBDV). Infectious rAAAV particles generated by the two strategies were harvested and titrated on CEF and CEL cells. A significantly higher viral titer was obtained with the helper activity provided by the pHelper vector than by MDV or CELO virus. Further experiments showed that rAAAV-mediated green fluorescent protein (gfp) expression was overtly enhanced by MDV or CELO virus super infection or treatment with sodium butyric acid, but not by IBDV super infection. These data demonstrated that MDV and CELO viruses could provide weak helper activity for propagation of rAAAV, and rAAAV-mediated transgene expression could be enhanced by super infection with the helper viruses.

  15. Adsorption onto Activated Carbon Fiber Cloth and Electrothermal Desorption of Volatile Organic Compound (VOCs): A Specific Review

    Institute of Scientific and Technical Information of China (English)

    Pierre Le Cloirec

    2012-01-01

    A general research program, focusing on activated carbon fiber cloths (ACFC) and felt for environmental protection was performed. The objectives were multiple: (i) a better understanding of the adsorption mecha- nisms of these kinds of materials; (ii) the specification and optimization of new processes using these adsorbents; (iii) the modeling of the adsorption of organic pollutants using both the usual and original approaches; (iv) applications of ACFC in industrial processes. The general question was: how can activated carbon fiber cloths and felts be used in air treatment processes for the protection of environment. In order to provide an answer, different approaches were adopted. The materials (ACFC) were characterized in terms of macro structure and internal porosity. Specific studies were performed to get the air flow pattern through the fabrics. Head loss data were generated and modeled as a fi.mction of air velocity. The performances of ACF to remove volatile organic compounds (VOCs) were approached with the adsorption isotherms and breakthrough curves in various operating conditions. Regenera- tion by Joule effect shows a homogenous heating of adsorber modules with rolled or pleated layers. Examples of industrial developments were presented showing an interesting technology for the removal of VOCs, such as dichloromethane, benzene, isopropyl alcohol and toluene, alone or in a complex mixture.

  16. Expression and purification of biologically active recombinant human paraoxonase 1 from inclusion bodies of Escherichia coli.

    Science.gov (United States)

    Bajaj, Priyanka; Tripathy, Rajan K; Aggarwal, Geetika; Pande, Abhay H

    2015-11-01

    Human PON1 (h-PON1) is a Ca(2+)-dependent serum enzyme and can hydrolyze (and inactivate) a wide range of substrates. It is a multifaceted enzyme and exhibit anti-inflammatory, anti-oxidative, anti-atherogenic, anti-diabetic, anti-microbial, and organophosphate (OP)-detoxifying properties. Thus, h-PON1 is a strong candidate for the development of therapeutic intervention against these conditions in humans. Insufficient hydrolyzing activity of native h-PON1 against desirable substrate affirms the urgent need to develop improved variant(s) of h-PON1 having enhanced activity. Production of recombinant h-PON1 (rh-PON1) using an Escherichia coli expression system is a key to develop such variant(s). However, generation of rh-PON1 using E. coli expression system has been elusive until now because of the aggregation of over-expressed rh-PON1 protein in inactive form as inclusion bodies (IBs) in the bacterial cells. In this study, we have over-expressed rh-PON1(wt) and rh-PON1(H115W;R192K) proteins as IBs in E. coli, and refolded the inactive enzymes present in the IBs to their active form using in vitro refolding. The active enzymes were isolated from the refolding mixture by ion-exchange chromatography. The catalytic properties of the refolded enzymes were similar to their soluble counterparts. Our results show that the pure and the active variant of rh-PON1 enzyme having enhanced hydrolyzing activity can be produced in large quantities using E. coli expression system. This method can be used for the industrial scale production of rh-PON1 enzymes and will aid in developing h-PON1 as a therapeutic candidate.

  17. Pharmacokinetics of human recombinant tissue-type plasminogen activator, administered intra-abdominally, in a rat peritonitis model

    NARCIS (Netherlands)

    van Goor, Harry; Bom, VJJ; van der Meer, J; Sluiter, WJ; Geerards, S; de Graaf, JS; Bleichrodt, RP; van der Schaaf, W

    1996-01-01

    Human recombinant tissue-type plasminogen activator (rtPA), administered intraperitoneally, may promote intraabdominal fibrinolysis in peritonitis, thereby preventing adhesion and abscess formation. The pharmacokinetics of a single intraperitoneal dose of 0.5 or 2.0 mg/ml human rtPA were assessed in

  18. Prolonged binding of radiolabeled recombinant tissue-type plasminogen activator after angioplasty and enclosed thrombolysis of the femoropopliteal arteries

    DEFF Research Database (Denmark)

    Tønnesen, K H; Vinberg, N; Folkenborg, O

    1992-01-01

    The authors measured the binding of indium-111-labeled recombinant tissue-type plasminogen activator (rt-PA) within the recanalized femoropopliteal segment after percutaneous transluminal angioplasty (PTA) and enclosed thrombolysis. In patients with long occlusions (n = 3), 91 micrograms of rt...

  19. Treatment of massive gastrointestinal bleeding occurred during autologous stem cell transplantation with recombinant activated factor VII and octreotide

    Directory of Open Access Journals (Sweden)

    Erman Atas

    2015-01-01

    Full Text Available After hematopoietic stem cell transplantation (HSCT, patients may suffer from bleeding. One of the bleeding type is gastrointestinal (GI which has serious morbidity and mortality in children with limited treatment options. Herein, we presented a child with upper GI bleeding post autologous HSCT controlled successfully by using recombinant activated factor VII (rFVIIa and octreotide infusion.

  20. Recombinant tissue plasminogen activator as a novel treatment option for infective endocarditis: a retrospective clinical study in 32 children.

    Science.gov (United States)

    Levitas, Aviva; Krymko, Hanna; Richardson, Justin; Zalzstein, Eli; Ioffe, Viktoriya

    2016-01-01

    Infective endocarditis is a life-threatening infectious syndrome, with high morbidity and mortality. Current treatments for infective endocarditis include intravenous antibiotics, surgery, and involve a lengthy hospital stay. We hypothesised that adjunctive recombinant tissue plasminogen activator treatment for infective endocarditis may facilitate faster resolution of vegetations and clearance of positive blood cultures, and therefore decrease morbidity and mortality. This retrospective study included follow-up of patients, from 1997 through 2014, including clinical presentation, causative organism, length of treatment, morbidity, and mortality. We identified 32 patients, all of whom were diagnosed with endocarditis and were treated by recombinant tissue plasminogen activator. Among all, 27 patients (93%) had positive blood cultures, with the most frequent organisms being Staphylococcus epidermis (nine patients), Staphylococcus aureus (six patients), and Candida (nine patients). Upon treatment, in 31 patients (97%), resolution of vegetations and clearance of blood cultures occurred within hours to few days. Out of 32 patients, one patient (3%) died and three patients (9%) suffered embolic or haemorrhagic events, possibly related to the recombinant tissue plasminogen activator. None of the patients required surgical intervention to assist vegetation resolution. In conclusion, it appears that recombinant tissue plasminogen activator may become an adjunctive treatment for infective endocarditis and may decrease morbidity as compared with current guidelines. Prospective multi-centre studies are required to validate our findings.

  1. Activation of human T cells by a tumor vaccine infected with recombinant Newcastle disease virus producing IL-2

    NARCIS (Netherlands)

    Janke, M.; Peeters, B.; Zhao, H.; Leeuw, O.; Moormann, R.J.M.; Arnold, A.; Ziouta, Y.; Fournier, P.; Schirrmacher, V.

    2008-01-01

    A new recombinant (rec) Newcastle disease virus (NDV) with incorporated human interleukin 2 (IL-2) as foreign therapeutic gene [rec(IL-2)] will be described. The foreign gene in rec(IL-2) did not affect the main features of NDV replication nor its tumor selectivity. Biologically active IL-2 was prod

  2. Active immunotherapy of allergic asthma with a recombinant human interleukin-5 protein as vaccine in a murine model

    Institute of Scientific and Technical Information of China (English)

    TAN Guang-hong; WANG Cai-chun; HUANG Feng-ying; WANG Hua; HUANG Yong-hao; LIN Ying-ying

    2007-01-01

    Background Eosinophils are highly related to allergic asthma inflammation. Interleukin (IL)-5 is the major chemokine of eosinophils, inhibition of the activity of IL-5 thus seems to be a potential approach to asthma therapy. The current study was performed to determine whether a recombinant human IL-5 protein as a xenogeneic vaccine has the capability of inducing anti-asthma activities.Methods Recombinant human IL-5 was used as a protein vaccine. Mouse asthma model was established to observe the anti-asthma activities. Lung histology was observed; eosinophils in blood and bronchoalveolar lavage were stained and counted. Airway hyperresponsiveness was determined by whole body plethysmograph. Antibody characters and cytokines were detected with enzyme linked immunosorbent assay (ELISA) and Western blot assay.Results Vaccination with recombinant human IL-5 protein as vaccine significantly reduced airway inflammation and airway hyperresponsiveness, and shifted the cytokine production from Th2 (IL-4) to Th1 (INF-γ) in mice allergic-asthma model. Immunization with recombinant human IL-5 protein vaccine bypassed the immunological tolerance and induced production of polyclonal antibodies that were cross-reactive with murine IL-5.Conclusions Active immunization with xenogeneic homologous IL-5 may be a possible therapeutic approach to the treatment of asthma and potentially of other eosinophilic disorders.

  3. Using recombinant CD74 protein to inhibit the activity of macrophage migration inhibitory factor (MIF) in vitro

    Institute of Scientific and Technical Information of China (English)

    Zhi-xinSHAN; Xi-yongYU; Qiu-xiongLIN; Yong-hengFU

    2005-01-01

    AIM Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine involved in the pathogenesis of a variety of autoimmune and inflammatory diseases, including arthritis, glomerulonephritis, Gram-positive and Gram-negative sepsis, and atherogenesis. Recent studies showed that CD74(antigen-associated invariant chain Ⅱ) is a high-affinity membrane-binding protein for MIF. The purpose of the present study was to express the recombinant human CD74 in E. coli and inhibit the activity of MIF by using recombinant CD74 in vitro.

  4. Restricted expression of recombination activating gene (RAG-1) in mouse lymphoid tissues

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Akihito; Fujinaga, Hiroyuki; Hamatani, Kiyohiro [Radiation Effects Research Foundation, Nagasaki (Japan). Nagasaki Branch; Atsuta, Mitsuru

    1993-03-01

    In an attempt to determine the distribution of recombinase activity in the mouse thymus, spleen, and lymph nodes, we used the in situ hybridization method to examine the expression of the recombination activating genes RAG-1 and RAG-2. Expression of RAG-1 was found in most cortical thymocytes but not in the majority of medullary thymocytes. Although hybridization signals of RAG-2 were not as intense as those of RAG-1, the localization of RAG-2 transcripts was similar to that of RAG-1. In the spleen, expression of RAG-1 was found only in limited cells near the splenic sinus, and the majority of the cells within the follicle were negative for RAG-1 transcript. In nude mice, RAG-1-expressing cells were detected in the same regions, which suggests that in situ hybridization signals of RAG-1 in the spleen are due to the cells of B-cell origin. In the lymph nodes, expression of RAG-1 was found only in the medullary region. Expression of RAG-2 transcript in the spleen and the lymph nodes, if any, was too faint to allow determination of the specific localization. These results suggest that most of the cortical thymocytes and some cells in the spleen are capable of rearranging T-cell receptor genes and immunoglobulin genes, respectively, but the possible involvement of the RAG-1 transcript in RAG-1-positive cells of the spleen and the lymph nodes in functions other than the rearrangement of genes could not be ruled out. (author).

  5. The cloning, expression and purification of recombinant human neuritin from Escherichia coli and the partial analysis of its neurobiological activity.

    Science.gov (United States)

    Li, Yuanyuan; Tang, Juan; Zhang, Yunhua; Wang, Haiyan; Yuan, Wumei; Yu, Na; Luo, Xing; Xu, Xiaoling; Huang, Jin; Yang, Lei

    2015-12-01

    Neuritin (Nrn1) is a neurotrophic factor that plays various roles in neural development and synaptic plasticity. In this study, the NRN1 gene was cloned and expressed in Escherichia coli and then recombinant neuritin protein was purified so that its neurobiological activity could be evaluated. The protein, which was obtained at a concentration of 0.45 mg/ml and > 90% purity, had the predicted molecular weight of 30 kDa, as determined via sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Western blot analysis confirmed that an anti-neuritin antibody could recognize the fusion protein. Subsequent functional analyses revealed that recombinant neuritin promoted neurite outgrowth in embryonic chicken dorsal root ganglia and PC12 cells. These results suggest that recombinant neuritin protein could be a valuable tool for inducing neurite regeneration, for instance in cases of spinal cord injury or neurological diseases. PMID:26751893

  6. Beryllium Desorption from Sediments

    Science.gov (United States)

    Boschi, V.; Willenbring, J. K.

    2015-12-01

    Beryllium isotopes have provided a useful tool in the field of geochronology and geomorphology over the last 25 years. The amount of cosmogenic meteoric 10Be and native 9Be absorbed to soils often scales with the residence time and chemical weathering of sediments in a landscape, respectively. Thus, the concentrations in river sediment may be used to quantify the denudation of specific watersheds. When deposited in ocean sediment, these concentrations are thought to record the history of denudation on Earth over the last ~10 Ma. The use of both isotopes often relies on the premise of beryllium retention to sediment surfaces in order to preserve a landscape's erosion and weathering signature. Changes in setting, en route from the soil to fluvial system to the ocean, can cause beryllium desorption and may preclude some applications of the 10Be/9Be system. Four mechanisms were tested to determine the desorption potential of beryllium including a reduction in pH, an increase in ionic strength and complexation with soluble organic and inorganic species. These processes have the potential to mobilize beryllium into solution. For example, by both reducing the pH and increasing the ionic strength, competition for adsorption sites increases, potentially liberating beryllium from the sediment surface. In addition, organic and inorganic ligands can complex beryllium causing it to become mobilized. To determine which of these alterations influence beryllium desorption and to quantify the effect, we prepared separate solutions of beryllium bound to minerals and organic compounds and measured beryllium concentrations in solution before and after adjusting the pH, ionic strength, and changing inorganic and organic ligand concentrations. We conclude from our observations that overall, beryllium sorbed to organic compounds was more resistant to desorption relative to mineral-associated beryllium. Among the methods tested, a reduction in pH resulted in the greatest amount of

  7. Thermal desorption of PTCDA on Cu(111)

    International Nuclear Information System (INIS)

    Organic molecules often show very complex thermal desorption spectra. If there is an ordered structure the activation energy for desorption Edes will decrease for the first few layers because of the decreasing van der Waals interaction of the layers to the substrate. This is especially true for the system 3,4,9,10 perylene-tetracarboxylic-dianhydride on Cu(111). The spectra consist of three different signals which can be attributed to the second layer, the multilayer and a crystal phase. The numerical algorithm sketched in this paper gives a desorption energy of 2.35eV for the second layer and 2.2eV for the multilayer

  8. Evaluation of Aryoseven Safety (Recombinant Activated Factor VII) in Patients with Bleeding Disorders (An Observational Post-Marketing Surveillance Study)

    Science.gov (United States)

    Toogeh, Gholamreza; Abolghasemi, Hassan; Eshghi, Peyman; Managhchi, Mohammadreza; Shaverdi-niasari, Mohammadreza; Karimi, Katayoon; Roostaei, Samin; Emran, Neda; Abdollahi, Alireza

    2016-01-01

    Background: Recombinant activated factor VII induces hemostasis in patients with coagulopathy disorders. AryoSeven™ as a safe Iranian Recombinant activated factor VII has been available on our market. This study was performed to establish the safety of AryoSeven on patients with coagulopathy disorder. Methods: This single-center, descriptive, cross sectional study was carried out in Thrombus and Homeostasis Research Center ValiAsr Hospital during 2013-2014. Fifty one patients with bleeding disorders who received at least one dose of Aryoseven were enrolled. Patients’ demographic data and adverse effect of drug and reaction related to Aryoseven or previous usage of Recombinant activated FVII were recorded in questionnaires. Finally data were analyzed to compare side effects of Aryoseven and other Recombinant activated FVII brands. Results: Aryoseven was prescribed for 51 Patients. Of all participants with mean age 57.18+21.38 yr, 31 cases were male and 26 subjects had past history of recombinant activated FVII usage. Glanzman was the most frequent disorder followed by congenital FVII deficiency, hemophilia with inhibitors, factor 5 deficiency, acquired hemophilia, hemophilia A with inhibitor, and hemophilia A or B with inhibitor. The majority of bleeding episodes had occurred in joints. Three patients (5.9%) complained about adverse effects of Aryoseven vs. 11.5 % about adverse effects of other brands. However this difference was not significant, statistically. Conclusion: Based on monitor patients closely for any adverse events, we concluded that Aryoseven administration under careful weighing of benefit versus potential harm may comparable with other counterpart drugs. PMID:27799968

  9. Activity of Recombinant Human Interleukin-15 against Tumor Recurrence and Metastasis in Mice

    Institute of Scientific and Technical Information of China (English)

    Feng Tang; Luting Zhao; Yan Jiang; Denian Ba; Lianxian Cui; Wei He

    2008-01-01

    Transplantable experimental tumor models were constructed to study the activities of recombinant human interleukin-15 (rhIL-15) against tumor recurrence and metastasis. The results showed that tumor nodule formation was retarded and tumor growth was inhibited in the subcutaneous tumor model of LA795 lung adenocarcinoma after treatment with rhIL-15, and the survival rate of T739 tumor-bearing mice treated with rhIL-15 was much higher than that of mice treated with either saline or with the same dose of rhIL-2. This indicats that rhIL-15 had better antitumor effect than rhIL-2 at the same dose level. In some rhIL-15 treated mice, the tumor cells inoculated subcutaneously were eradicated and there was no tumor formation even 138 days after tumor cell inoculation. The tumor-free mice were rechallenged with live tumor cells and no tumor reoccurred in the following two months in all of these mice, indicating that long-lasting antitumor systemic immunity developed. It was also shown that tumor recurrence and metastasis were inhibited markedly after treatment with rhIL-15, but not with the same dose of rhIL-2, in both subcutaneously and intravenously disseminated tumor models of LA795 lung adenocarcinoma. Simultaneously, the CTL and NK cell activities of the splenocytes obtained from tumor-bearing mice that had been treated with either rhIL-15 or rhIL-2 were both markedly enhanced. However, the enhancement of CTL and NK cell activities was more significant in rhIL-15 treated mice than that in rhIL-2 treated mice. This suggests that the anti-tumor effect of rhIL-15 in vivo was achieved by enhancing the CTL and NK cell activities in tumor immune response. Cellular & Molecular Immunology. 2008;5(3):189-196.

  10. Molecular cloning, recombinant gene expression, and antifungal activity of cystatin from taro (Colocasia esculenta cv. Kaosiung no. 1).

    Science.gov (United States)

    Yang, A H; Yeh, K W

    2005-06-01

    A cDNA clone, designated CeCPI, encoding a novel phytocystatin was isolated from taro corms (Colocasia esculenta) using both degenerated primers/RT-PCR amplification and 5'-/3'-RACE extension. The full-length cDNA gene is 1,008 bp in size, encodes 206 amino acid residues, with a deduced molecular weight of 29 kDa. It contains a conserved reactive site motif Gln-Val-Val-Ser-Gly of cysteine protease inhibitors, and another consensus ARFAV sequence for phytocystatin. Sequence analysis revealed that CeCPI is phylogenetically closely related to Eudicots rather than to Monocots, despite taro belonging to Monocot. Recombinant GST-CeCPI fusion protein was overexpressed in Escherichia coli and its inhibitory activity against papain was identified on gelatin/SDS-PAGE. These results confirmed that recombinant CeCPI protein exhibited strong cysteine protease inhibitory activity. Investigation of its antifungal activity clearly revealed a toxic effect on the mycelium growth of phytopathogenic fungi, such as Sclerotium rolfsii Sacc. etc., at a concentration of 80 microg recombinant CeCPI/ ml. Moreover, mycelium growth was completely inhibited and the sclerotia lysed at a concentration of 150-200 microg/ml. Further studies have demonstrated that recombinant CeCPI is capable of acting against the endogenous cysteine proteinase in the fungal mycelium.

  11. Recombinant-activated factor Ⅶ and neuronal apoptosis in a rat model of intracerebral hemorrhage

    Institute of Scientific and Technical Information of China (English)

    Qiang Li; Wei Li; Suju Ding; Jianping Tang; Jing Fang; Benqiang Deng; Tao Wu

    2009-01-01

    BACKGROUND:Activated clotting factor Ⅶ has been demonstrated to exhibit obvious anti-apoptosis effects.OBJECTIVE:To observe the effect of activated clotting factor Ⅶ on neuronal apoptosis at different time points following rat intracerebral hemorrhage (ICH).DESIGN,TIME AND SETTING:A randomized,controlled,animal experiment was performed at the Neurobiological Laboratory of Second Military Medical University from October 2005 to April 2006.MATERIALS:Recombinant-activated clotting factor Vlla (rFⅧa) was purchased from Danish Novo Nordisk,Denmark.In situ cell death detection kit-POD kit was purchased from Roche,Switzerland.Caspase-3 activity determination kit from Biovision,USA.METHODS:A total of 72 healthy,male,Sprague Dawley rats,aged 5-8 months,were randomly assigned to three groups (n=24):sham-operated,ICH model,and rFⅧa.In the ICH model and rFⅧa groups,80.0 μL autologous non-clotting blood from rat tails was injected into the right caudate putamen to establish the ICH.The empty microinjector was inserted into the caudate putamen in the sham-operated group.The ICH model and rFⅧa groups were subdivided into four subsets separately:6,24,72 hours and 7 clays following ICH.The rats in the rFⅧa group were injected with 160 μg/kg rFⅧa via the dorsal vein of the penis.MAIN OUTCOME MEASURES:Apoptotic cells were detected in the right caudate putamen by TUNEL;caspase-3 activity by spectrophotometry;and rat neurological function was evaluated by neurological functional impairment scales.RESULTS:Rat neurological function was deteriorated at 24,72 hours,and 7 days following ICH.The TUNEL-positive cells and caspase-3 activity in the right caudate putamen was significantly increased in the ICH rats (P<0.05);rFVlla treatment reduced the number of TUNEL-positive cells and caspase-3 activity in the right caudate putamen (P<0.05),and neurological function was significantly improved (P<0.05).CONCLUSION:rFⅧa was applied within 72 hours after ICH,which reduced

  12. Product desorption limitations in selective photocatalytic oxidation

    NARCIS (Netherlands)

    Renckens, T.J.A.; Almeida, A.R.; Damen, M.R.; Kreutzer, M.T.; Mul, G.

    2010-01-01

    The rate of photocatalytic processes can be significantly improved if strongly bound products rapidly desorb to free up active sites. This paper deals with the rate of desorption of cyclohexanone, the product of the liquid-phase photo-oxidation of cyclohexane. Dynamic step-response and pulse-respons

  13. Analysis of the technique Thermal Desorption Spectroscopy (TDS) and its Application for the Characterization of Metal -Hydrogen Systems

    International Nuclear Information System (INIS)

    limiting step is the recombination of two hydrogen atoms on the surface of the material. When the surface of the sample is in the a phase (solid solution) the rate limiting step is one of the processes that occurs on the surface of the material: the transfer of a hydrogen atom from the bulk to the surface or the recombination and desorption on the surface. By fitting the spectra we obtain an activation energy equal to 31 n 6 kJ/mol for the b phase, and equal to 35 n 3 kJ/mol for the a phase. We also compare the spectra of the powder with the spectra of the granules, foils and wires. Based on this comparison we analyze the effect on the desorption spectra of the characteristic size and geometry of the samples.Finally, we present a study of hydrogen desorption in the Pd-H system poisoned with sulfur. The poisoning produces as main effects a delay of the absorption and desorption processes without any appreciable loss in the storage capacity of the material.The experimental apparatus and theoretical models developed have been applied to the study of a MH system using samples with different morphology, characteristic size, geometry and surface state. The spectra were measured for different hydrogen concentrations and heating speeds. The results obtained encourage the utilization of TDS for the study and characterization of hydrogen desorption in MH systems. The technique is suited for the detailed analysis of the physical properties of the system and for the qualitative evaluation of the kinetic processes and their possible influence on technological devices

  14. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production

    OpenAIRE

    Raheem Ullah; Majid Ali Shah; Soban Tufail; Fouzia Ismat; Muhammad Imran; Mazhar Iqbal; Osman Mirza; Moazur Rhaman

    2016-01-01

    Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally ...

  15. Purification and characterization of biologically active recombinant human Eppin expressed in Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    ZHU Qing-yi; GU Xiao-jian; YANG Jin; WANG Jun-hong; TANG Bo; WU Hong-fei

    2008-01-01

    Background Eppin(epididymis protease inhibitor)appears to play an important role in primate fertility.However,the function of Eppin and its antibody in men and its relationship with men's infertility are poorly studied.To reveal the significance and possibility of detection of anti-Eppin antibody in clinical infertilty cases,we developed an Escherichia coli expression system for the expression of biologically actire human Eppin.Methods The human Eppin gene was cloned into PET-28a(+)vector after induction with 0.5 mmol/L isopropy-β-D-thiogalactoside(IPTG)at 26℃ for 4 hours,and the expressed fusion protein His6-Eppin was purified by Ni2+ affinity chromatography.Afterwards,six female 8-week-old Balb/c mice were immunized with purified His6-Eppin for three weeks.Their sera were collected and polyclonal antibodies against His6-Eppin were purified,all of which were further verified by Western-blot and immunofluorescence analysis.Results About 18.33 mg His6-Eppin was obtained from 1-L flask culture.The produced polyclonal antibodies against His6-Eppin recognized the Eppin protein both in human epididymis and in HEK293T cells by over-expression of the recombinant human Eppin.Conclusion The purified His6-Eppin protein has biological activity,which might be a candidate for clinical diagnosis of infertility and development of male immuno-contraceptive agents.

  16. High cytokine production and effective antitumor activity of a recombinant vaccinia virus encoding murine interleukin 12.

    Science.gov (United States)

    Meko, J B; Yim, J H; Tsung, K; Norton, J A

    1995-11-01

    We have constructed a recombinant vaccinia virus (recVV), vKT0334 mIL-12, containing the genes encoding the p35 and p40 subunits of murine interleukin-12 (mIL-12). In vitro experiments demonstrated that vKT0334 mIL-12 efficiently infected a variety of murine and human tumor cell lines and produced very high amounts (1.5 micrograms/10(6) cells/24 h) of biologically active mIL-12. Mice injected s.c. with 10(6) MCA 105 sarcoma cells, followed by injection at the same site with saline or a control recVV, vKT033, containing no mIL-12 genes, all developed progressively growing tumor, whereas 60% of animals injected with vKT0334 mIL-12 remained tumor free (P < 0.0005). Furthermore, tumor growth was significantly reduced in the remaining mice treated with vKT0334 mIL-12 that did develop tumor compared with mice treated with vKT033 (P < 0.03) or saline (P < 0.0001). We conclude that recVV expressing high levels of mIL-12 offers an effective in vivo method of cytokine gene delivery and expression in tumors with subsequent antitumor effect.

  17. Early intracardiac thrombosis in preterm infants and thrombolysis with recombinant tissue type plasminogen activator

    Science.gov (United States)

    Ferrari, F; Vagnarelli, F; Gargano, G; Roversi, M; Biagioni, O; Ranzi, A; Cavazzuti, G

    2001-01-01

    OBJECTIVES—To determine the incidence of catheter related thrombosis and to test the efficacy of recombinant tissue type plasminogen activator (rt-PA) in preterm infants.
STUDY DESIGN—From January 1995 to December 1998, echocardiography was performed in the first few days of life in 76 very low birthweight (⩽ 1500 g) infants out of a total of 147 having an umbilical catheter placed. When intracardiac thrombosis was diagnosed, rt-PA infusion was performed.
RESULTS—Four infants (5%) developed an intracardiac thrombosis during the first few days of life. In three of them, rt-PA at a dose of 0.4-0.5 mg/kg in a 20-30 minute bolus led to dissolution of the clot. One patient received a three hour infusion after the bolus, at a dose of 0.1 mg/kg/h, with resolution of the thrombus. No systemic effects were observed after rt-PA infusion.
CONCLUSIONS—Early thrombosis may occur as a complication of umbilical catheterisation in preterm infants; early echocardiographic detection of this disorder allows complete, safe, and rapid lysis with rt-PA.

 PMID:11420328

  18. Recombinant interleukin 2 stimulates in vivo proliferation of adoptively transferred lymphokine-activated killer (LAK) cells

    International Nuclear Information System (INIS)

    The authors previously reported that the adoptive transfer of lymphokine-activated killer (LAK) cells plus repetitive injections of recombinant interleukin 2 (IL 2) produced a marked reduction in established pulmonary metastases from a variety of murine sarcomas. The requirement for the exogenous administration of IL 2 prompted a subsequent examination of the role of IL 2 in the in vivo function of transferred LAK cells. The in vivo proliferation and migration patterns of lymphoid cells in C57BL/6 mice were examined after i.v. transfer of LAK cells alone, i.p. injection of IL 2 alone, or the combination of LAK cells and IL 2. A model for in vivo labeling of the DNA of dividing cells was used in which mice were injected with 5-[125I]-iodo-2'-deoxyuridine (125IUdR) and, 20 hr later, their tissues were removed and were counted in a gamma analyzer. A proliferation index (PI) was calculated by dividing the mean cpm of organs of experimentally treated mice by the mean cpm of organs of control mice. In animals given LAK cells alone, the lungs and liver demonstrated little if any uptake of 125IUdR above saline-treated controls, whereas the same organs of mice receiving 6000 U of IL 2 alone displayed higher radiolabel incorporation. When mice were given LAK cells plus 6000 U of IL 2, their tissues showed an additional increase in 125IUdR uptake

  19. Factors predicting intracerebral hemorrhage of patients treated with intravenous recombinant tissue plasminogen activator

    International Nuclear Information System (INIS)

    The use of recombinant tissue plasminogen activator (rt-PA) was approved in Japan in October 2005, and has had a marked effect on the treatment of patients presenting with acute ischemic stroke. Since the administration of rt-PA might cause intracerebral hemorrhage (ICH) and a poor prognosis, it is necessary to identify predictors of ICH after treatment with rt-PA. In this article, we examined 58 consecutive patients with acute ischemic stroke treated with intravenous rt-PA within 3 hours of symptom onset for 45 months, March 2006 to November 2009. In principle, we evaluated patients before and one day after rt-PA with MRI. We made a retrospective comparison of 21 patients with hemorrhagic change on CT and MRI T2* within 36 hours and 37 patients without hemorrhagic change. The rate of ICH with or without symptoms was increased with a higher National Institutes of Health Stroke Scale (NIHSS) and infarction range, defined by diffusion weighted imaging (DWI) Alberta Stroke Programme Early CT Score (ASPECTS). Major artery occlusion and reperfusion, including partial recanalization in MR angiography (MRA), were taken as factors in the hemorrhage group. In conclusion, DWI ASPECTS and NIHSS were useful predictors of ICH after rt-PA administration. (author)

  20. Recombinant N-Terminal Slit2 Inhibits TGF-β-Induced Fibroblast Activation and Renal Fibrosis.

    Science.gov (United States)

    Yuen, Darren A; Huang, Yi-Wei; Liu, Guang-Ying; Patel, Sajedabanu; Fang, Fei; Zhou, Joyce; Thai, Kerri; Sidiqi, Ahmad; Szeto, Stephen G; Chan, Lauren; Lu, Mingliang; He, Xiaolin; John, Rohan; Gilbert, Richard E; Scholey, James W; Robinson, Lisa A

    2016-09-01

    Fibrosis and inflammation are closely intertwined injury pathways present in nearly all forms of CKD for which few safe and effective therapies exist. Slit glycoproteins signaling through Roundabout (Robo) receptors have been described to have anti-inflammatory effects through regulation of leukocyte cytoskeletal organization. Notably, cytoskeletal reorganization is also required for fibroblast responses to TGF-β Here, we examined whether Slit2 also controls TGF-β-induced renal fibrosis. In cultured renal fibroblasts, which we found to express Slit2 and Robo-1, the bioactive N-terminal fragment of Slit2 inhibited TGF-β-induced collagen synthesis, actin cytoskeletal reorganization, and Smad2/3 transcriptional activity, but the inactive C-terminal fragment of Slit2 did not. In mouse models of postischemic renal fibrosis and obstructive uropathy, treatment with N-terminal Slit2 before or after injury inhibited the development of renal fibrosis and preserved renal function, whereas the C-terminal Slit2 had no effect. Our data suggest that administration of recombinant Slit2 may be a new treatment strategy to arrest chronic injury progression after ischemic and obstructive renal insults by not only attenuating inflammation but also, directly inhibiting renal fibrosis.

  1. Evidence supporting the use of recombinant activated factor VII in congenital bleeding disorders

    Directory of Open Access Journals (Sweden)

    Pär I Johansson

    2010-06-01

    Full Text Available Pär I Johansson, Sisse R OstrowskiCapital Region Blood Bank, Section for Transfusion Medicine, Rigshospitalet, University of Copenhagen, Copenhagen, DenmarkBackground: Recombinant activated factor VII (rFVIIa, NovoSeven® was introduced in 1996 for the treatment of hemophilic patients with antibodies against coagulation factor VIII or IX.Objective: To review the evidence supporting the use of rFVIIa for the treatment of patients with congenital bleeding disorders.Patients and methods: English-language databases were searched in September 2009 for reports of randomized controlled trials (RCTs evaluating the ability of rFVIIa to restore hemostasis in patients with congenital bleeding disorders.Results: Eight RCTs involving 256 hemophilic patients with antibodies against coagulation factors, also known as inhibitors, were identified. The evidence supporting the use of rFVIIa in these patients was weak with regard to dose, clinical setting, mode of administration, efficacy, and adverse events, given the limited sample size of each RCT and the heterogeneity of the studies.Conclusion: The authors suggest that rFVIIa therapy in hemophilic patients with inhibitors should be based on the individual’s ability to generate thrombin and form a clot, and not on the patient’s weight alone. Therefore, assays for thrombin generation, such as whole-blood thromboelastography, have the potential to significantly improve the treatment of these patients.Keywords: hemophilia, inhibitors, coagulation factor VIII, coagulation factor IX, rFVIIa, NovoSeven, FEIBA, hemostasis, RCT

  2. Novel recombinant adeno-associated viruses for Cre activated and inactivated transgene expression in neurons

    Directory of Open Access Journals (Sweden)

    Arpiar eSaunders

    2012-07-01

    Full Text Available Understanding the organization of the nervous system requires methods for dissecting the contributions of each component cell type to circuit function. One widely used approach combines genetic targeting of Cre recombinase to specific cell populations with infection of recombinant adeno-associated viruses (rAAVs whose transgene expression is activated by Cre (Cre-On. Distinguishing how the Cre-expressing neurons differ functionally from neighboring Cre-negative neurons requires rAAVs that are inactivated by Cre (Cre-Off and can be used in tandem with Cre-On viruses. Here we introduce two rAAV vectors that are inactivated by Cre and carry different fluorophore and optogenetic constructs. We demonstrate single and dual rAAV systems to achieve Cre-On and Cre-Off expression in spatially-intermingled cell populations of the striatum. Using these systems, we uncovered cryptic genomic interactions that occur between multiple Cre-sensitive rAAVs or between Cre-sensitive rAAVs and somatic Cre-conditional alleles and devised methods to avoid these interactions. Our data highlight both important experimental caveats associated with Cre-dependent rAAV use as well as opportunities for the development of improved rAAVs for gene delivery.

  3. Reduction of sidewall interface recombination in GaAs and InGaAs active regions

    Science.gov (United States)

    Strand, Timothy Andrew

    In the continual effort to reduce the operating current in semiconductor lasers, the first step is always to reduce the size of the device. When we do so, however, we encounter a new set of challenges. As the device size decreases, the "walls close in" on the electrons and holes, that is, the sidewalls of the device become so close together that the electrons and holes can diffuse to them before recombining radiatively. The device sidewalls, are often littered with carrier traps, which act as nonradiative recombination sites for the electrons and holes. This wasted current, a small fraction of the total in larger devices, becomes the dominant current mechanism in small devices. In this work we present two techniques for limiting this sidewall interface recombination. The first uses semiconductor regrowth to remove the recombination sites that are normally formed at the air-exposed sidewalls. We use buried, in-plane lasers to demonstrate a reduction in the sidewall recombination rate by a factor of forty. In the second technique, we show that the sidewall interface recombination can also be reduced by preventing the carriers from diffusing to the sidewalls. We demonstrate two methods for reducing this lateral carrier diffusion; segmented GaAs quantum wells, and InGaAs quantum dots. In the former, we demonstrate a reduction in the low-temperature lateral carrier diffusion constant by a factor of forty-six (versus a comparable GaAs quantum well).

  4. Recombinant interferon alfa-2a, an active agent in advanced cutaneous T-cell lymphomas.

    Science.gov (United States)

    Bunn, P A; Ihde, D C; Foon, K A

    1987-01-01

    The cutaneous T-cell lymphomas including mycosis fungoides and the Sézary syndrome, are indolent lymphomas with early systemic dissemination. Like the indolent B-cell lymphomas, they cannot be cured by currently available systemic chemotherapy so new systemic therapies need to be developed. A study of very high-dose recombinant interferon alfa-2a was, therefore, initiated in 20 patients with advanced cutaneous T-cell lymphoma (5 in stage II, 2 in stage III and 13 in stage IV). All patients were refractory to at least 2 standard therapies, including topical nitrogen mustard (18 patients), psoralens and ultraviolet A light (12 patients), total skin electron irradiation (14 patients) and systemic chemotherapy (16 patients). Nine out of 20 patients (45%; 95% confidence interval 25-69%) had either objective partial or complete responses within 3 months of starting treatment. Maximal response, however, often did not occur for at least one year. The median duration of response was 5.5 months and all complete responses lasted more than 2 years. Response frequencies were equal at both cutaneous and extracutaneous sites and in patients with or without prior chemotherapy. Toxicity was exhibited primarily as a flu-like syndrome consisting of fever, malaise, fatigue, anorexia and weight loss which necessitated dose reductions in all patients. Transient elevations in liver function and decreases in renal function and granulocyte counts occurred in some patients. It is concluded that interferon alfa-2a is highly active against advanced cutaneous T-cell lymphomas and that it should be studied in its early stages. It should also be evaluated in combination with other biological agents and with chemotherapy.

  5. Characterization of a defensin from the oyster Crassostrea gigas - Recombinant production, folding, solution structure, antimicrobial activities, and gene expression

    OpenAIRE

    Gueguen, Yannick; Herpin, Amaury; Aumelas, André; Garnier, Julien; Fievet, Julie; Escoubas, Jean-Michel; Bulet, Philippe; Gonzalez, Marcelo; Lelong, Christophe; Favrel, Pascal; Bachere, Evelyne

    2006-01-01

    In invertebrates, defensins were found in arthropods and in the mussels. Here, we report for the first time the identification and characterization of a defensin (Cg-Def) from an oyster. Cg-def mRNA was isolated from Crassostrea gigas mantle using an expressed sequence tag approach. To gain insight into potential roles of Cg-Def in oyster immunity, we produced the recombinant peptide in Escherichia coli, characterized its antimicrobial activities, determined its solution structure by NMR spec...

  6. Intravenous Recombinant Tissue Plasminogen Activator Thrombolysis in a Patient with Acute Ischemic Stroke Secondary to Aortic Dissection

    OpenAIRE

    Hong, Keun-Sik; Park, So-Young; Whang, Seon-Il; Seo, So-Young; Lee, Dong-Ha; Kim, Han-Joon; Cho, Joong-Yang; Cho, Yong-Jin; Jang, Woo-Ik; Kim, Chang Young

    2008-01-01

    Background Acute ischemic stroke secondary to aortic dissection (AoD) is challenging in the era of thrombolysis owing to the diagnostic difficulty within a narrow time window and the high risk of complications. Case Report A 64-year-old woman with middle cerebral artery occlusion syndrome admitted to the emergency room within intravenous recombinant tissue plasminogen activator (rt-PA) time window. Her neurological symptoms improved during thrombolysis, but chest and abdominal pain developed....

  7. Recombinant human activated protein C inhibits local and systemic activation of coagulation without influencing inflammation during Pseudomonas aeruginosa pneumonia in rats

    NARCIS (Netherlands)

    Choi, Goda; Hofstra, Jorrit-Jan H; Roelofs, Joris J T H; Florquin, Sandrine; Bresser, Paul; Levi, Marcel; van der Poll, Tom; Schultz, Marcus J

    2007-01-01

    OBJECTIVE: Alveolar fibrin deposition is a hallmark of pneumonia. It has been proposed that recombinant human activated protein C exerts lung-protective effects via anticoagulant and anti-inflammatory pathways. We investigated the role of the protein C system in pneumonia caused by Pseudomonas aerug

  8. β-苯乙醇在不同类型多孔材料上的脱附活化能%Desorption activation energy ofβ-phenylethyl alcohol on different type of porous materials

    Institute of Scientific and Technical Information of China (English)

    王明锋; 熊智勇; 刘娟; 黄艳

    2014-01-01

    采用程序升温脱附(TPD)实验技术测定了β-苯乙醇在5种多孔材料上的TPD曲线,并估算了它们的脱附活化能。同时还讨论了多孔材料的孔径结构和表面性质对β-苯乙醇吸附结合力的影响规律。结果表明:(1)β-苯乙醇在多孔材料上的脱附活化能(kJ/mol)由低到高依次为:B型硅胶(46.90)、SBA-15分子筛(56.16)、A型硅胶(67.92)、MCM-41分子筛(86.16)和XF型活性炭(91.87);(2)除XF型活性炭外,吸附剂表面酸性基团的增加有利于增强其对β-苯乙醇的吸附结合力,β-苯乙醇在吸附剂上的脱附活化能随吸附剂表面酸性基团含量的升高而增大;(3)与其它几种多孔材料相比,XF型活性炭与β-苯乙醇之间因存在π键吸附使得吸附作用力增强,脱附活化能也较高。%Temperature programmed desorption (TPD) technique was applied to measure TPD curves ofβ-phenethyl alcohol on five types of porous materials, and desorption activation energy of phenethyl alcohol was estimated. Effects of pore structure and surface properties of these porous materials on desorption activation energy of phenyl ethyl alcohol were also discussed. Results showed that:(1) Desorption activation energy (kJ/mol) ofβ-phenethyl alcohol on porous materials was in the following order:silica gel B(46.90 kJ/mol)activated carbon XF (91.87 kJ/mol);(2) With exception of activated carbon XF, the higher the surface acidic group content of an adsorbent, the stronger the interaction ofβ-phenethyl alcohol that adsorbent became, and the higher the desorption activation energy;(3) Since there was strongπ-Complexation betweenβ-phenylethyl alcohol and activated carbon, desorption activation energy ofβ-phenethyl alcohol on activated carbon was higher compared to that on other porous materials.

  9. Influence of Different Types of Recombination Active Defects on the Integral Electrical Properties of Multicrystalline Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Dominik Lausch

    2015-01-01

    Full Text Available In this contribution the influence of different types of recombination-active defects on the integral electrical properties of multicrystalline Si solar cells is investigated. Based on a previous classification scheme related to the luminescence behavior of crystal defects, Type-A and Type-B defects are locally distinguished. It is shown that Type-A defects, correlated to iron contaminations, are dominating the efficiency by more than 20% relative through their impact on the short circuit current ISC and open circuit voltage VOC in standard Si material (only limited by recombination active crystal defects. Contrarily, Type-B defects show low influence on the efficiency of 3% relative. The impact of the detrimental Type-A defects on the electrical parameters is studied as a function of the block height. A clear correlation between the area fraction of Type-A defects and both the global Isc and the prebreakdown behavior (reverse current in voltage regime-2 (−11 V is observed. An outlier having an increased full-area recombination activity is traced back to dense inter- and intragrain nucleation of Fe precipitates. Based on these results it is concluded that Type-A defects are the most detrimental defects in Si solar cells (having efficiencies > 15% and have to be prevented by optimized Si material quality and solar cell process conditions.

  10. Highly selective anti-Prelog synthesis of optically active aryl alcohols by recombinant Escherichia coli expressing stereospecific alcohol dehydrogenase.

    Science.gov (United States)

    Li, Ming; Nie, Yao; Mu, Xiao Qing; Zhang, Rongzhen; Xu, Yan

    2016-07-01

    Biocatalytic asymmetric synthesis has been widely used for preparation of optically active chiral alcohols as the important intermediates and precursors of active pharmaceutical ingredients. However, the available whole-cell system involving anti-Prelog specific alcohol dehydrogenase is yet limited. A recombinant Escherichia coli system expressing anti-Prelog stereospecific alcohol dehydrogenase from Candida parapsilosis was established as a whole-cell system for catalyzing asymmetric reduction of aryl ketones to anti-Prelog configured alcohols. Using 2-hydroxyacetophenone as the substrate, reaction factors including pH, cell status, and substrate concentration had obvious impacts on the outcome of whole-cell biocatalysis, and xylose was found to be an available auxiliary substrate for intracellular cofactor regeneration, by which (S)-1-phenyl-1,2-ethanediol was achieved with an optical purity of 97%e.e. and yield of 89% under the substrate concentration of 5 g/L. Additionally, the feasibility of the recombinant cells toward different aryl ketones was investigated, and most of the corresponding chiral alcohol products were obtained with an optical purity over 95%e.e. Therefore, the whole-cell system involving recombinant stereospecific alcohol dehydrogenase was constructed as an efficient biocatalyst for highly enantioselective anti-Prelog synthesis of optically active aryl alcohols and would be promising in the pharmaceutical industry.

  11. Characterization and immunological activity of different forms of recombinant secreted Hc of botulinum neurotoxin serotype B products expressed in yeast.

    Science.gov (United States)

    Liu, Bo; Shi, DanYang; Chang, ShaoHong; Gong, Xin; Yu, YunZhou; Sun, ZhiWei; Wu, Jun

    2015-01-01

    The recombinant Hc proteins of botulinum neurotoxins and tetanus toxin are exclusively produced by intracellular heterologous expression in Pichia pastoris for use in subunit vaccines; the same Hc proteins produced by secreted heterologous expression are hyper-glycosylated and immunologically inert. Here, several different recombinant secreted Hc proteins of botulinum neurotoxin serotype B (BHc) were expressed in yeast and we characterized and assessed their immunological activity in detail. Recombinant low-glycosylated secreted BHc products (BSK) were also immunologically inert, similar to hyper-glycosylated BHc products (BSG), although deglycosylation restored their immunological activities. Unexpectedly, deglycosylated proBHc contained an unexpected pro-peptide of an α-factor signal and fortuitous N-linked glycosylation sites in the non-cleaved pro-peptide sequences, but not in the BHc sequences. Notably, a non-glycosylated secreted homogeneous BHc isoform (mBHc), which we successfully prepared after deleting the pro-peptide and removing its single potential glycosylation site, was immunologically active and could confer effective protective immunity, similarly to non-glycosylated rBHc. In summary, we conclude that a non-glycosylated secreted BHc isoform can be prepared in yeast by deleting the pro-peptide of the α-factor signal and mutating its single potential glycosylation site. This approach provides a rational and feasible strategy for the secretory expression of botulism or other toxin antigens. PMID:25567004

  12. Evaluation of recombinant activated protein C for severe sepsis at a tertiary academic medical center

    Directory of Open Access Journals (Sweden)

    Anger KE

    2013-06-01

    Full Text Available Kevin E Anger,1 Jeremy R DeGrado,1 Bonnie C Greenwood,1 Steven A Cohen,2 Paul M Szumita1 1Department of Pharmacy, Brigham and Women’s Hospital, Boston, MA, USA; 2Department of Family Medicine and Population Health, Division of Epidemiology, Virginia Commonwealth University, Richmond, VA, USA Purpose: Early clinical trials of recombinant human activated protein C (rhAPC for severe sepsis excluded patients at high risk of bleeding. Recent literature suggests bleeding rates are higher in clinical practice and may be associated with worsened outcomes. Our objective was to evaluate baseline demographics; incidence, and risk factors for major bleeding; and mortality of patients receiving rhAPC for severe sepsis at our institution. Methods: A retrospective study was performed for all patients receiving rhAPC for treatment of severe sepsis at a tertiary academic medical center from January 2002 to June 2009. Demographic information, clinical variables, intensive care unit, and hospital outcomes were recorded. Results: Of the 156 patients that received rhAPC, 54 (34.6% did not meet institutional criteria for safe use at baseline due to bleeding precaution or contraindication. Twenty-three (14.7% patients experienced a major bleeding event. Multivariate analysis demonstrated baseline International Normalized Ratio ≥2.5 (odds ratio [OR] 3.68, 95% confidence interval [CI]: 1.28–10.56; P = 0.03 and platelet count ≤100 × 103/mm3 (OR 2.86, 95% CI: 1.07–7.67; P = 0.01 as significant predictors of a major bleed. Overall hospital mortality was 57.7%. Multivariate analysis demonstrated the presence of ≥3 organ dysfunctions (OR 2.46, 95% CI: 1.19–5.09; P < 0.05 and medical intensive care unit admission (OR 1.99, 95% CI: 1.00–3.98; P = 0.05 were independent variables associated with hospital mortality. Conclusion: Patients receiving rhAPC at our institution had higher APACHE II scores, mortality, and major bleeding events than published

  13. Comparison of real time RT-PCR and flow cytometry methods for evaluation of biological activity of recombinant human erythropoietin

    Directory of Open Access Journals (Sweden)

    Sepehrizadeh Z

    2008-05-01

    Full Text Available Background: Evaluation of bioactivity of recombinant erythropoietin is essential for pharmaceutical industry, quality control authorities and researchers. The purpose of this study was to compare real time RT-PCR and flow cytometry for the assay of biological activity of recombinant erythropoietin. Methods: Three concentrations of recombinant erythropoietin BRP (80, 40 and 20 IU/ml were injected subcutaneously to mice. After 4 days the blood was collected and used for reticulocyte counts by flow cytometry and also for the RNA extraction. Real time RT-PCR amplification was carried out for β-globin. Results and conclusion: There was a significant correlation between the total RNA amounts (R2= 0.9995, relative quantity of β-globin mRNA (R2= 0.984 and reticulocyte counts (R2= 0.9742 with rhEpo concentrations. Total RNA and quantitative RT-PCR showed significant dose dependent results as well the reticulocyte counts by flow cytometry for the biological activity assay of rhEpo and so these methods could be considered as alternatives for flow cytometry.

  14. Deconstructing Desorption Electrospray Ionization: Independent Optimization of Desorption and Ionization by Spray Desorption Collection

    Science.gov (United States)

    Douglass, Kevin A.; Jain, Shashank; Brandt, William R.; Venter, Andre R.

    2012-11-01

    Spray desorption collection (SDC) and reflective electrospray ionization (RESI) were used to independently study the desorption and ionization processes that together comprise desorption electrospray ionization (DESI). Both processes depend on several instrumental parameters, including the nebulizing gas flow rate, applied potential, and source geometries. Each of these parameters was optimized for desorption, as represented by the results obtained by SDC, and ionization, as represented by the results obtained by RESI. The optimized conditions were then compared to the optimization results for DESI. Our results confirm that optimal conditions for desorption and ionization are different and that in some cases the optimized DESI conditions are a compromise between both sets. The respective results for DESI, RESI, and SDC for each parameter were compared across the methods to draw conclusions about the contribution of each parameter to desorption and ionization separately and then combined within DESI. Our results indicate that desorption efficiency is (1) independent of the applied potential and (2) the impact zone to inlet distance, and that (3) gas pressure settings and (4) sprayer to impact zone distances above optimal for DESI are detrimental to desorption but beneficial for ionization. In addition, possible interpretations for the observed trends are presented.

  15. Plasmid construction using recombination activity in the fission yeast Schizosaccharomyces pombe.

    Directory of Open Access Journals (Sweden)

    Ayako Chino

    Full Text Available BACKGROUND: Construction of plasmids is crucial in modern genetic manipulation. As of now, the common method for constructing plasmids is to digest specific DNA sequences with restriction enzymes and to ligate the resulting DNA fragments with DNA ligase. Another potent method to construct plasmids, known as gap-repair cloning (GRC, is commonly used in the budding yeast Saccharomyces cerevisiae. GRC makes use of the homologous recombination activity that occurs within the yeast cells. Due to its flexible design and efficiency, GRC has been frequently used for constructing plasmids with complex structures as well as genome-wide plasmid collections. Although there have been reports indicating GRC feasibility in the fission yeast Schizosaccharomyces pombe, this species is not commonly used for GRC as systematic studies of reporting GRC efficiency in S. pombe have not been performed till date. METHODOLOGY/PRINCIPAL FINDINGS: We investigated GRC efficiency in S. pombe in this study. We first showed that GRC was feasible in S. pombe by constructing a plasmid that contained the LEU2 auxotrophic marker gene in vivo and showed sufficient efficiency with short homology sequences (>25 bp. No preference was shown for the sequence length from the cut site in the vector plasmid. We next showed that plasmids could be constructed in a proper way using 3 DNA fragments with 70% efficiency without any specific selections being made. The GRC efficiency with 3 DNA fragments was dramatically increased >95% in lig4Delta mutant cell, where non-homologous end joining is deficient. Following this approach, we successfully constructed plasmid vectors with leu1+, ade6+, his5+, and lys1+ markers with the low-copy stable plasmid pDblet as a backbone by applying GRC in S. pombe. CONCLUSIONS/SIGNIFICANCE: We concluded that GRC was sufficiently feasible in S. pombe for genome-wide gene functional analysis as well as for regular plasmid construction. Plasmids with different

  16. Base composition, selection, and phylogenetic significance of indels in the recombination activating gene-1 in vertebrates

    Directory of Open Access Journals (Sweden)

    Vences Miguel

    2009-12-01

    Full Text Available Abstract Background The Recombination Activating Proteins, RAG1 and RAG2, play a crucial role in the immune response in vertebrates. Among the nuclear markers currently used for phylogenetic purposes, Rag1 has especially enjoyed enormous popularity, since it successfully contributed to elucidating the relationships among and within a large variety of vertebrate lineages. We here report on a comparative investigation of the genetic variation, base composition, presence of indels, and selection in Rag1 in different vertebrate lineages (Actinopterygii, Amphibia, Aves, Chondrichthyes, Crocodylia, Lepidosauria, Mammalia, and Testudines through the analysis of 582 sequences obtained from Genbank. We also analyze possible differences between distinct parts of the gene with different type of protein functions. Results In the vertebrate lineages studied, Rag1 is over 3 kb long. We observed a high level of heterogeneity in base composition at the 3rd codon position in some of the studied vertebrate lineages and in some specific taxa. This result is also paralleled by taxonomic differences in the GC content at the same codon position. Moreover, positive selection occurs at some sites in Aves, Lepidosauria and Testudines. Indels, which are often used as phylogenetic characters, are more informative across vertebrates in the 5' than in the 3'-end of the gene. When the entire gene is considered, the use of indels as phylogenetic character only recovers one major vertebrate clade, the Actinopterygii. However, in numerous cases insertions or deletions are specific to a monophyletic group. Conclusions Rag1 is a phylogenetic marker of undoubted quality. Our study points to the need of carrying out a preliminary investigation on the base composition and the possible existence of sites under selection of this gene within the groups studied to avoid misleading resolution. The gene shows highly heterogeneous base composition, which affects some taxa in particular and

  17. Recombinant receptor/reporter gene bioassays for assessing the estrogenic and dioxin-like activities of xenobiotics and complex mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Zacharewski, T. [Univ. of Western Ontario, London, Ontario (Canada). Dept. of Pharmacology and Toxicology

    1995-12-31

    Exposure to naturally occurring or synthetic substances that possess sex steroid and/or dioxin-like activity may have long range effects on human health, reproductive fitness and environmental quality. Results from recent epidemiological studies have suggested that xenobiotics with sex steroid activity may contribute to the development of hormone-dependent cancers and disorders in the male reproductive tract as well as attenuate sperm production. However, most of these compounds, which are referred to as endocrine disruptors, are structurally dissimilar to sex steroids. Yet, based upon ambiguous assays, it has been conceded that the effects of these compounds are mediated by receptors. The authors have taken advantage of the mechanism of action of these compounds to develop recombinant receptor/reporter gene bioassays for environmental estrogens and dioxin-like compounds. The assays use an easily measurable enzyme activity (i.e. firefly luciferase), exhibit improved sensitivity and selectivity and are amenable to automation. Data will be presented demonstrating that phytoestrogens (e.g. genistein) and xenobiotics such as pesticides (e.g. DDT, Kepone), nonionic surfactants (e.g. p-nonylphenol), and precursors used in the manufacture of plastics (e.g. Bisphenol A) exhibit estrogenic activity. In addition, the assays have been used to detect estrogenic and dioxin-like activity in complex mixtures such as pulp and paper mill black liquor and effluent. These results demonstrate the utility of recombinant receptor/reporter gene bioassays for identifying substances or complex mixtures with estrogenic and/or dioxin-like activity.

  18. Crystallization and preliminary crystallographic analysis of latent, active and recombinantly expressed aurone synthase, a polyphenol oxidase, from Coreopsis grandiflora

    Energy Technology Data Exchange (ETDEWEB)

    Molitor, Christian; Mauracher, Stephan Gerhard; Rompel, Annette, E-mail: annette.rompel@univie.ac.at [Universität Wien, Althanstrasse 14, 1090 Wien (Austria)

    2015-05-22

    Latent and active aurone synthase purified from petals of C. grandiflora (cgAUS1) were crystallized. The crystal quality of recombinantly expressed latent cgAUS1 was significantly improved by co-crystallization with the polyoxotungstate Na{sub 6}[TeW{sub 6}O{sub 24}] within the liquid–liquid phase-separation zone. Aurone synthase (AUS), a member of a novel group of plant polyphenol oxidases (PPOs), catalyzes the oxidative conversion of chalcones to aurones. Two active cgAUS1 (41.6 kDa) forms that differed in the level of phosphorylation or sulfation as well as the latent precursor form (58.9 kDa) were purified from the petals of Coreopsis grandiflora. The differing active cgAUS1 forms and the latent cgAUS1 as well as recombinantly expressed latent cgAUS1 were crystallized, resulting in six different crystal forms. The active forms crystallized in space groups P2{sub 1}2{sub 1}2{sub 1} and P12{sub 1}1 and diffracted to ∼1.65 Å resolution. Co-crystallization of active cgAUS1 with 1,4-resorcinol led to crystals belonging to space group P3{sub 1}21. The crystals of latent cgAUS1 belonged to space group P12{sub 1}1 and diffracted to 2.50 Å resolution. Co-crystallization of recombinantly expressed pro-AUS with the hexatungstotellurate(VI) salt Na{sub 6}[TeW{sub 6}O{sub 24}] within the liquid–liquid phase separation zone significantly improved the quality of the crystals compared with crystals obtained without hexatungstotellurate(VI)

  19. The biological activity of a recombinantly expressed (His)(6)-tagged peanut allergen (rAra h 1) is unaffected by endotoxin removal

    DEFF Research Database (Denmark)

    Jensen, Louise Bjerremann; Torp, Anna Maria; Andersen, Sven Bode;

    2008-01-01

    The application of recombinant (His)(6)-tagged proteins in cell culture assays is associated with problems due to lipopolysaccharide (LPS) contamination. LPS stimulates cells of the immune system, thereby masking antigen-specific activation of T cells. Due to the affinity of LPS for histidine...... it is associated with difficulties to remove LPS from recombinant (His)(6)-tagged proteins. Here we describe that the Triton X-114 phase separation method can be used to remove LPS from (His)(6)-tagged proteins and that the recombinant proteins retain their biological activity....

  20. Temperature programmed desorption of weakly bound adsorbates on Au(111)

    Science.gov (United States)

    Engelhart, Daniel P.; Wagner, Roman J. V.; Meling, Artur; Wodtke, Alec M.; Schäfer, Tim

    2016-08-01

    We have performed temperature programmed desorption (TPD) experiments to analyze the desorption kinetics of Ar, Kr, Xe, C2H2, SF6, N2, NO and CO on Au(111). We report desorption activation energies (Edes), which are an excellent proxy for the binding energies. The derived binding energies scale with the polarizability of the molecules, consistent with the conclusion that the surface-adsorbate bonds arise due to dispersion forces. The reported results serve as a benchmark for theories of dispersion force interactions of molecules at metal surfaces.

  1. Activation of Coagulation by Administration of Recombinant Factor VIIa Elicits Interleukin 6 (IL-6) and IL-8 Release in Healthy Human Subjects

    OpenAIRE

    de Jonge, Evert; Friederich, Philip W.; Vlasuk, George P.; Rote, William E.; Vroom, Margaretha B.; Levi, Marcel; van der Poll, Tom

    2003-01-01

    The activation of coagulation has been shown to contribute to proinflammatory responses in animal and in vitro experiments. Here we report that the activation of coagulation in healthy human subjects by the administration of recombinant factor VIIa also elicits a small but significant increase in the concentrations of interleukin 6 (IL-6) and IL-8 in plasma. This increase was absent when the subjects were pretreated with recombinant nematode anticoagulant protein c2, the inhibitor of tissue f...

  2. Active, soluble recombinant melittin purified by extracting insoluble lysate of Escherichia coli without denaturation

    OpenAIRE

    Buhrman, Jason S; Cook, Laura C.; Rayahin, Jamie E; Federle, Michael J.; Gemeinhart, Richard A.

    2013-01-01

    Cell lytic peptides are a class of drugs that can be used to selectively kill invading organisms or diseased cells. Several of these peptides have been identified as potential therapeutics. Herein, we report a novel process for purifying recombinant melittin, a cell lytic peptide that inserts into the membranes of cells causing cell lysis, from Escherichia coli. The process involves surfactant and low pH to solubilize melittin fusion proteins from the insoluble fraction of bacterial lysates. ...

  3. Generation of Biologically Active Multi-Sialylated Recombinant Human EPOFc in Plants

    OpenAIRE

    Alexandra Castilho; Laura Neumann; Pia Gattinger; Richard Strasser; Karola Vorauer-Uhl; Thomas Sterovsky; Friedrich Altmann; Herta Steinkellner

    2013-01-01

    Hyperglycosylated proteins are more stable, show increased serum half-life and less sensitivity to proteolysis compared to non-sialylated forms. This applies particularly to recombinant human erythropoietin (rhEPO). Recent progress in N-glycoengineering of non-mammalian expression hosts resulted in in vivo protein sialylation at great homogeneity. However the synthesis of multi-sialylated N-glycans is so far restricted to mammalian cells. Here we used a plant based expression system to accomp...

  4. Optimisation of recombinant production of active human cardiac SERCA2a ATPase

    OpenAIRE

    Antaloae, Ana V.; Cédric Montigny; Marc le Maire; Watson, Kimberly A.; Thomas L-M Sørensen

    2013-01-01

    Methods for recombinant production of eukaryotic membrane proteins, yielding sufficient quantity and quality of protein for structural biology, remain a challenge. We describe here, expression and purification optimisation of the human SERCA2a cardiac isoform of Ca(2+) translocating ATPase, using Saccharomyces cerevisiae as the heterologous expression system of choice. Two different expression vectors were utilised, allowing expression of C-terminal fusion proteins with a biotinylation domain...

  5. Inhibition on the production of collagen type Ⅰ, Ⅲ of activated hepatic stellate cells by antisense TIMP-1 recombinant plasmid

    Institute of Scientific and Technical Information of China (English)

    Wen-Bin Liu; Chang-Qing Yang; Wei Jiang; Yi-Qing Wang; Jing-Sheng Guo; Bo-Ming He; Ji-Yao Wang

    2003-01-01

    AIM: To investigate the inhibition effects on the productionof collagen type I, Ⅲ secreted by activated rat hepatic stellatecells (rHSCs) by antisense tissue inhibitors of metalloproteinase1 (TIMP-1) recombinant plasmid through elevating interstitialcollagenase activity.METHODS: rHSCs were extracted from normal rat liverby pronase and collagenase digestion and purified bycentrifugal elutriation, and were cultured on plastic dishesuntil they were activated to a myofibroblastic phenotypeafter 7-10 days. RT-Nest-PCR and gene recombinanttechniques were used to construct the rat antisense TIMP-1 recombinant plasmids which can express in eucaryoticcells. The recombinant plasmid and the pcDNA3 emptyplasmid were transfected in rHSCs by Effectene (QIAGEN)separately. Cells were selected after growing in DMEMcontaining 400 μg/ml G418 for 2-3 weeks. Expression ofexogenous gene was assessed by Northern blot, andexpression oflIMP-1 in rHSCs was determined by Northernblot and Western blot. We tested the interstitial collagenaseactivity with FITC-labled type I collagen as substrate.Ultimately, we quantified the type Ⅰ, Ⅲ collagen byWestern blot.RESULTS: The exogenous antisense TIMP-1 recombinantplasmid could be expressed in rHSCs well, which couldblock the expression of TIMP-1 greatly, the ratio of TIMP-1/GAPDH was 0.67, 2.41, and 2.97 separately at mRNAlevel (P<0.05); the ratio of TIMP-1/β-actin was 0.31, 0.98and 1.32 separately at protein level (P<0.05); It mightelevate active and latent interstitial collagenase activity,the collagenase activity was 0.3049, 0.1411 and 0.1196respectively. (P<0.05), which led to promotion thedegradation of type Ⅰ, Ⅲ collagen, the ratio of collagen I/β-actin was 0.63, 1.78 and 1.92 separately (P<0.05); andthe ratio of collagen Ⅲ/β-actin was 0.59, 1.81 and 1.98separately (P<0.05).CONCLUSION: These data shows that the antisense TIMP-1 recombinant plasmid has the inhibitory effects on theproduction of type Ⅰ, Ⅲ collagens

  6. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production.

    Directory of Open Access Journals (Sweden)

    Raheem Ullah

    Full Text Available Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications.

  7. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production.

    Science.gov (United States)

    Ullah, Raheem; Shah, Majid Ali; Tufail, Soban; Ismat, Fouzia; Imran, Muhammad; Iqbal, Mazhar; Mirza, Osman; Rhaman, Moazur

    2016-01-01

    Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications. PMID:27093053

  8. Characterisation of aroma profiles of commercial sufus by odour activity value, gas chromatography-olfactometry, aroma recombination and omission studies.

    Science.gov (United States)

    Xiao, Zuobing; Shang, Yi; Chen, Feng; Niu, Yunwei; Gu, Yongbo; Liu, Shengjiang; Zhu, Jiancai

    2015-01-01

    Sufu is a solid-state fermented product made from soya beans. For the sake of quality control and regulation purposes, it is essential to be able to identify key odorants of various commercial sufus. To identify the aroma-active compounds in sufus, gas chromatography-olfactometry/aroma extract dilution analysis (GC-O/AEDA) was performed, and odour activity value (OAV) was estimated. The correlations between aroma profiles and identified aroma-active compounds were also investigated by principal component analysis. Results showed that 35 aroma-active compounds were detected through OAV calculation, while 28 compounds were identified by using GC-O/AEDA. Quantitative descriptive analysis revealed that aroma recombination model based on OAV calculation was more similar to original sufu in terms of aroma comparing to aroma recombination model based on GC-O/AEDA. Omission experiments further confirmed that the aroma compounds, such as ethyl butanoate, ethyl 2-methylbutanoate, ethyl hexanoate, (E,E)-2,4-decadienal and 2,6-dimethylpyrazine, contributed most significantly to the characteristic aroma of a commercial sufu. PMID:25790084

  9. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production.

    Science.gov (United States)

    Ullah, Raheem; Shah, Majid Ali; Tufail, Soban; Ismat, Fouzia; Imran, Muhammad; Iqbal, Mazhar; Mirza, Osman; Rhaman, Moazur

    2016-01-01

    Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its stringent sequence specificity and enhanced activity. Like other proteases, activity of the human rhinovirus 3C protease can be affected in part by the buffer components and additives that are generally employed for purification and stabilization of proteins, hence, necessitate their removal by tedious and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three different fusion proteins at 4°C, a temperature of choice for purification of many proteins. The results show that the human rhinovirus 3C protease performs better at 4°C than the frequently used tobacco etch virus protease and its activity was insensitive to most of the experimental conditions tested. Though number of fusion proteins tested is limited, we expect that these finding will facilitate the use of the human rhinovirus 3C protease in recombinant protein production for pharmaceutical and biotechnological applications.

  10. Expression and Purification of Active Recombinant Cathepsin C (Dipeptidyl Aminopeptidase I of Kuruma Prawn Marsupenaeus japonicus in Insect Cells

    Directory of Open Access Journals (Sweden)

    Gao-Feng Qiu

    2009-01-01

    Full Text Available Cathepsin C (CTSC is a lysosomal cysteine protease belonging to the papain superfamily. Our previous study showed that CTSC precursor (zymogen is localized exclusively in cortical rods (CRs of mature oocyte in the kuruma prawn Marsupenaeus japonicus, suggesting that CTSC might have roles on regulating release and/or formation of a jelly layer. In this study, enzymically active CTSC of the kuruma prawn was prepared by recombinant expression in the High Five insect cell line. The recombinant enzyme with a polyhistidine tag at its C-terminus was considered to be initially secreted into the culture medium as an inactive form of zymogen, because Western blot with anti-CTSC antibody detected a 51 kDa protein corresponding to CTSC precursor. After purification by affinity chromatography on nickel-iminodiacetic acid resin, the enzyme displayed three forms of 51, 31, and 30 kDa polypeptides. All of the forms can be recognized by antiserum raised against C-terminal polyhistidine tag, indicating that the 31 and 30 kDa forms were generated from 51 kDa polypeptide by removal of a portion of the N-terminus of propeptide. Following activation at pH 5.5 and 37∘C for 40 hours under native conditions, the recombinant CTSC (rCTSC exhibited increased activity against the synthetic substrate Gly-Phe-β-naphthylamide and optimal pH at around 5. The purified rCTSC will be useful for further characterization of its exact physiological role on CRs release and/or formation of a jelly layer in kuruma prawn.

  11. Factors influencing clinical outcomes of acute ischemic stroke treated with intravenous recombinant tissue plasminogen activator

    Institute of Scientific and Technical Information of China (English)

    HUANG Yin-hui; ZHUO Shi-tu; CHEN Ya-fang; LI Ming-mei; LIN You-yu; YANG Mei-li; CHEN Zhen-jie

    2013-01-01

    Background Thrombolysis with recombinant tissue plasminogen activator (rt-PA) has gained international recognition,clinical outcomes following this thrombolytic therapy varied from patient to patient.Factors affecting clinical outcomes have not been well understood yet,so this retrospective case-control study aimed to investigate factors that may influence clinical outcomes of acute ischemic stroke treated with intravenous rt-PA.Methods One hundred and one patients with acute ischemic stroke who received intravenous rt-PA thrombolysis within 4.5 hours from disease onset were included.Patients were divided into good or poor outcome group according to modified Rankin Scale (mRS) score,good outcome group:mRS score of 0-1; poor outcome group:mRS of 2-6.Stroke characteristics were compared between the two groups.Factors for stroke outcomes were analyzed via univariate analysis and Logistic regression.Results Of the 101 patients studied,patients in good outcome group (n=55) were significantly younger than patients in poor outcome group (n=46,(62.82±14.25) vs.(68.81±9.85) years,P=0.029).Good outcome group had fewer patients with diabetic history (9.09% vs.28.26%,P=0.012),fewer patients with leukoaraiosis (7.27% vs.28.26%,P=0.005) and presented with lower blood glucose level ((5.72±1.76) vs.(6.72±1.32) mmol/L,P=0.012),lower systolic blood pressure level ((135.45±19.36) vs.(148.78±19.39) mmHg,P=0.003),lower baseline NIHSS score (12.02±5.26 vs.15.78±4.98,P=0.002) and shorter onset-to-treatment time (OTT) ((2.38±1.21) vs.(2.57±1.03) hours,P=0.044) than poor outcome group.Logistic regression analysis showed that absence of diabetic history (odds ratio (OR) 0.968 (95% CI 0.941-0.996)),absence of leukoaraiosis (OR 0.835 (95% CI 0.712-0.980)),lower baseline NIHSS score (OR 0.885 (95% CI 0.793-0.989)),lower pre-thrombolysis systolic blood pressure (OR 0.962 (95% CI 0.929-0.997)),and lower blood glucose level (OR 0.699 (95% CI 0.491-0.994)) before

  12. Activity of the Human Rhinovirus 3C Protease Studied in Various Buffers, Additives and Detergents Solutions for Recombinant Protein Production

    DEFF Research Database (Denmark)

    Ullah, Raheem; Shah, Majid Ali; Tufail, Soban;

    2016-01-01

    and time-consuming procedures before proteolysis can occur. To address this issue, we examined the effect of elution buffers used for common affinity based purifications, salt ions, stability/solubility and reducing agents, and detergents on the activity of the human rhinovirus 3C protease using three......Proteases are widely used to remove affinity and solubility tags from recombinant proteins to avoid potential interference of these tags with the structure and function of the fusion partner. In recent years, great interest has been seen in use of the human rhinovirus 3C protease owing to its...

  13. A cellulose-binding domain-fused recombinant human T cell connective tissue-activating peptide-III manifests heparanase activity.

    Science.gov (United States)

    Rechter, M; Lider, O; Cahalon, L; Baharav, E; Dekel, M; Seigel, D; Vlodavsky, I; Aingorn, H; Cohen, I R; Shoseyov, O

    1999-02-24

    The chemokine connective tissue-activating peptide (CTAP)-III, which belongs to the leukocyte-derived growth factor family of mediators, was previously shown to be mitogenic for fibroblasts. However, it has recently been shown that CTAP-III, released from platelets, can act like a heparanase enzyme and degrade heparan sulfate. This suggests that CTAP-III may also function as a proinflammatory mediator. We have successfully cloned CTAP-III from a lambdagt11 cDNA library of PHA-activated human CD4(+) T cells and produced recombinant CTAP-III as a fusion protein with a cellulose-binding domain moiety. This recombinant CTAP-III exhibited heparanase activity and released degradation products from metabolically labeled, naturally produced extracellular matrix. We have also developed polyclonal and monoclonal antibodies, and these antibodies against the recombinant CTAP-III detected the CTAP-III molecule in human T cells, polymorphonuclear leukocytes, and placental extracts. Thus, our study provides tools to examine further immune cell behavior in inflamed sites rich with extracellular moieties and proinflammatory mediators. PMID:10049766

  14. Sorption/desorption reversibility of polycyclic aromatic hydrocarbons (PAHs) in soils and carbonaceous materials

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guohui

    2008-07-01

    Understanding sorption/desorption is an important prerequisite for the prediction of fate and transport of pollutants in the environment. During the last two decades, numerous studies have reported hysteresis phenomenon for the interaction of hydrophobic organic contaminants (HOCs) with natural organic matter (NOM). It manifests as nonsingular sorption/desorption isotherms or different rates for sorption and desorption, where during desorption a higher affinity of a compound on a given sorbent and a longer time scale for release than for sorption is observed. Other studies showed that some of the reported sorption/desorption hysteresis phenomena are due to experimental artifacts, mainly resulting from non-attainment of sorption equilibrium before desorption experiments, which result in 'pseudo-hysteresis'. Except for the hypothesis of sorbent reconfiguration, clear experimental evidence for the physical or chemical mechanisms proposed to lead to hysteresis is still lacking. In this study, sorption/desorption equilibrium and kinetics of phenanthrene sorption/desorption from two soils and three carbonaceous samples were investigated using both batch and column techniques. The main objective of this work was to monitor hysteresis phenomenon by carefully recovering the solute mass in the system and to compare sorption/desorption equilibria and kinetics thermodynamically. Nonsingular isotherms and higher desorption enthalpies as well as increased activation energies with proceeding desorption are expected if significant hysteresis exists. Sorption-desorption cycles were carried out to compare equilibrium isotherms and associated sorption/desorption enthalpies (AeH, isosteric heats). Instead of the traditional decant-and-refill batch method, the experiments were conducted using a newly designed batch protocol, which enables the determination of sorption/desorption isotherms at different temperatures using a closed batch system. This method additionally allows

  15. A novel cold-active lipase from Candida albicans: cloning, expression and characterization of the recombinant enzyme.

    Science.gov (United States)

    Lan, Dong-Ming; Yang, Ning; Wang, Wen-Kai; Shen, Yan-Fei; Yang, Bo; Wang, Yong-Hua

    2011-01-01

    A novel lipase gene lip5 from the yeast Candida albicans was cloned and sequenced. Alignment of amino acid sequences revealed that 86-34% identity exists with lipases from other Candida species. The lipase and its mutants were expressed in the yeast Pichia pastoris, where alternative codon usage caused the mistranslation of 154-Ser and 293-Ser as leucine. 154-Ser to leucine resulted in loss of expression of Lip5, and 293-Ser to leucine caused a marked reduction in the lipase activity. Lip5-DM, which has double mutations that revert 154 and 293 to serine residues, showed good lipase activity, and was overexpressed and purified by (NH(4))(2)SO(4) precipitation and ion-exchange chromatography. The pure Lip5-DM was stable at low temperatures ranging from 15-35 °C and pH 5-9, with the optimal conditions being 15-25 °C and pH 5-6. The activation energy of recombinant lipase was 8.5 Kcal/mol between 5 and 25 °C, suggesting that Lip5-DM was a cold-active lipase. Its activity was found to increase in the presence of Zn(2+), but it was strongly inhibited by Fe(2+), Fe(3+), Hg(2+) and some surfactants. In addition, the Lip5-DM could not tolerate water-miscible organic solvents. Lip5-DM exhibited a preference for the short-and medium-chain length p-nitrophenyl (C4 and C8 acyl group) esters rather than the long chain length p-nitrophenyl esters (C12, C16 and C18 acyl group) with highest activity observed with the C8 derivatives. The recombinant enzyme displayed activity toward triacylglycerols, such as olive oil and safflower oil.

  16. A Novel Cold-Active Lipase from Candida albicans: Cloning, Expression and Characterization of the Recombinant Enzyme

    Directory of Open Access Journals (Sweden)

    Dong-Ming Lan

    2011-06-01

    Full Text Available A novel lipase gene lip5 from the yeast Candida albicans was cloned and sequenced. Alignment of amino acid sequences revealed that 86–34% identity exists with lipases from other Candida species. The lipase and its mutants were expressed in the yeast Pichia pastoris, where alternative codon usage caused the mistranslation of 154-Ser and 293-Ser as leucine. 154-Ser to leucine resulted in loss of expression of Lip5, and 293-Ser to leucine caused a marked reduction in the lipase activity. Lip5-DM, which has double mutations that revert 154 and 293 to serine residues, showed good lipase activity, and was overexpressed and purified by (NH42SO4 precipitation and ion-exchange chromatography. The pure Lip5-DM was stable at low temperatures ranging from 15–35 °C and pH 5–9, with the optimal conditions being 15–25 °C and pH 5–6. The activation energy of recombinant lipase was 8.5 Kcal/mol between 5 and 25 °C, suggesting that Lip5-DM was a cold–active lipase. Its activity was found to increase in the presence of Zn2+, but it was strongly inhibited by Fe2+, Fe3+, Hg2+ and some surfactants. In addition, the Lip5-DM could not tolerate water-miscible organic solvents. Lip5-DM exhibited a preference for the short- and medium-chain length p-nitrophenyl (C4 and C8 acyl group esters rather than the long chain length p-nitrophenyl esters (C12, C16 and C18 acyl group with highest activity observed with the C8 derivatives. The recombinant enzyme displayed activity toward triacylglycerols, such as olive oil and safflower oil.

  17. Generation of recombinant single-chain antibodies neutralizing the cytolytic activity of vaginolysin, the main virulence factor of Gardnerella vaginalis

    Directory of Open Access Journals (Sweden)

    Pleckaityte Milda

    2011-11-01

    Full Text Available Abstract Background Gardnerella vaginalis is identified as the predominant colonist of the vaginal tract in women with bacterial vaginosis. Vaginolysin (VLY is a protein toxin released by G. vaginalis. VLY possesses cytolytic activity and is considered as a main virulence factor of G. vaginalis. Inhibition of VLY-mediated cell lysis by antibodies may have important physiological relevance. Results Single-chain variable fragments of immunoglobulins (scFvs were cloned from two hybridoma cell lines producing neutralizing antibodies against VLY and expressed as active proteins in E. coli. For each hybridoma, two variants of anti-VLY scFv consisting of either VL-VH or VH-VL linked with a 20 aa-long linker sequence (G4S4 were constructed. Recovery of scFvs from inclusion bodies with subsequent purification by metal-chelate chromatography resulted in VLY-binding proteins that were predominantly monomeric. The antigen-binding activity of purified scFvs was verified by an indirect ELISA. The neutralizing activity was investigated by in vitro hemolytic assay and cytolytic assay using HeLa cell line. Calculated apparent Kd values and neutralizing potency of scFvs were in agreement with those of parental full-length antibodies. VH-VL and VL-VH variants of scFvs showed similar affinity and neutralizing potency. The anti-VLY scFvs derived from hybridoma clone 9B4 exhibited high VLY-neutralizing activity both on human erythrocytes and cervical epithelial HeLa cells. Conclusions Hybridoma-derived scFvs with VLY-binding activity were expressed in E. coli. Recombinant anti-VLY scFvs inhibited VLY-mediated cell lysis. The monovalent scFvs showed reduced affinity and neutralizing potency as compared to the respective full-length antibodies. The loss of avidity could be restored by generating scFv constructs with multivalent binding properties. Generated scFvs is the first example of recombinant single-chain antibodies with VLY-neutralizing activity produced in

  18. Human Recombinant PLD2 Can Repress p65 Activity of Guinea Pigs of Chronic Asthma in vivo

    Institute of Scientific and Technical Information of China (English)

    Ling Zhu; Weibin Zou; Chuanxing Yu; Junjin Lin; Xiaoli He

    2006-01-01

    This article is to investigate the effect of human recombinant phospholipase D2 (rhPLD2) in vivo on the expression of nuclear transcription factor p65 in chronic asthma of guinea pigs. After treating the guinea pigs with chronic asthma by rhPLD2, the crude nuclear extraction was assayed with TransAM Transcription Factor Assay Kit for the activity of pulmo tissue nuclear transcription factor p65. Compared with the healthy guinea pigs, the activity of nuclear transcription factor p65 in guinea pigs of chronic asthma is much higher than that of control groups. Our results showed that rhPLD2 markedly depressed the activity of p65 when the guinea pigs were attacked by chronic asthma. Cellular & Molecular Immunology. 2006;3(4):307-310.

  19. Recombination activity of light-activated copper defects in p-type silicon studied by injection- and temperature-dependent lifetime spectroscopy

    Science.gov (United States)

    Inglese, Alessandro; Lindroos, Jeanette; Vahlman, Henri; Savin, Hele

    2016-09-01

    The presence of copper contamination is known to cause strong light-induced degradation (Cu-LID) in silicon. In this paper, we parametrize the recombination activity of light-activated copper defects in terms of Shockley—Read—Hall recombination statistics through injection- and temperature dependent lifetime spectroscopy (TDLS) performed on deliberately contaminated float zone silicon wafers. We obtain an accurate fit of the experimental data via two non-interacting energy levels, i.e., a deep recombination center featuring an energy level at Ec-Et=0.48 -0.62 eV with a moderate donor-like capture asymmetry ( k =1.7 -2.6 ) and an additional shallow energy state located at Ec-Et=0.1 -0.2 eV , which mostly affects the carrier lifetime only at high-injection conditions. Besides confirming these defect parameters, TDLS measurements also indicate a power-law temperature dependence of the capture cross sections associated with the deep energy state. Eventually, we compare these results with the available literature data, and we find that the formation of copper precipitates is the probable root cause behind Cu-LID.

  20. Observations of the interaction of a plasma stream with neutral gas: evidence of plasma loss through molecular-activated recombination

    International Nuclear Information System (INIS)

    We describe an experiment, the UMIST Linear System (ULS), in which a hydrogen plasma stream, guided by a longitudinal magnetic field, is injected through a diaphragm containing an orifice into a separately-pumped target chamber in which the neutral hydrogen pressure can be raised to a maximum of 8 mTorr. The stream is about 6 mm in diameter, has an electron temperature of up to 15 eV and an ion flux of 3 018s-1; it is supersonic with Mach number up to M approx.= 3. We have studied both the passage of the stream through the orifice and the interaction of the supersonic plasma with neutral hydrogen in the target chamber. We find that transmission is incomplete even when the orifice diameter is five times that of the plasma; we attribute this to the presence of ion trajectories which extend well outside the visible plasma and are intercepted by the diaphragm. In the target chamber, the stream does not broaden, but the ion flux decreases approximately exponentially with distance, with a scale length of the order of the mean free path for momentum transfer in ion-neutral collisions, and much less than that expected for other processes, such as charge exchange or electron-ion recombination. Elastic collisions alone cannot decrease the flux, but would lead to a large accumulation of slow ions in thermal equilibrium with the neutral gas, which must be limited by some other loss process: collisional diffusion and electron-ion recombination are too slow, leading to a density approaching 1020m-3. The observed density is of the order of 1018m-3, requiring a process with a rate of 10-100 times faster. Calculated rates for molecular-activated recombination (MAR) of the slow ions are of this order, and the predicted density agrees with our observations to order of magnitude. (author)

  1. Homing of radiolabelled recombinant interleukin-2 activated natural killer cells and their efficacy in adoptive immunotherapy against murine fibrosarcoma

    Indian Academy of Sciences (India)

    Anuradha Rai; Ashim K Chakravarty

    2007-12-01

    Natural killer (NK) cells are spontaneously cytotoxic against tumour target cells. Their number was found to be four times more in the spleen of tumour-bearing Swiss albino mice. After activation with recombinant interleukin-2 (rIL-2), NK cells were tested and found to seek out the tumour site when injected intravenously in tumour-bearing mice. Their potential for fighting tumours in vivo was further seen following adoptive transfer of rIL-2 activated NK (A-NK) cells in tumour-bearing mice. After surgical removal of tumour load, adoptive transfer of A-NK cells inhibited tumour recurrence in 92.3% cases, thereby suggesting the use of this protocol for therapeutic purposes to obtain a better outcome.

  2. Generation and phenotypic analysis of a transgenic line of rabbits secreting active recombinant human erythropoietin in the milk.

    Science.gov (United States)

    Mikus, Tomás; Poplstein, Martin; Sedláková, Jirina; Landa, Vladimír; Jeníkova, Gabriela; Trefil, Pavel; Lidický, Jan; Malý, Petr

    2004-10-01

    Production of recombinant human erythropoietin (rhEPO) for therapeutic purposes relies on its expression in selected clones of transfected mammalian cells. Alternatively, this glycoprotein can be produced by targeted secretion into the body fluid of transgenic mammals. Here, we report on the generation of a transgenic rabbits producing rhEPO in the lactating mammary gland. Transgenic individuals are viable, fertile and transmit the rhEPO gene to the offspring. Northern blot data indicated that the expression of the transgene in the mammary gland is controlled by whey acidic protien (WAP) regulatory sequences during the period of lactation. While the hybridization with total RNA revealed the expression only in the lactating mammary gland, the highly sensitive combinatory approach using RT-PCR/hybridization technique detected a minor ectopic expression. The level of rhEPO secretion in the founder female, measured in the period of lactation, varied in the range of 60-178 and 60-162 mIU/ml in the milk and blood plasma, respectively. Biological activity of the milk rhEPO was confirmed by a standard [3H]-thymidine incorporation test. Thus, we describe the model of a rhEPO-transgenic rabbit, valuable for studies of rhEPO glycosylation and function, which can be useful for the development of transgenic approaches designed for the preparation of recombinant proteins by alternative biopharmaceutical production.

  3. Recombinant Expression of a Novel Fungal Immunomodulatory Protein with Human Tumor Cell Antiproliferative Activity from Nectria haematococca

    Directory of Open Access Journals (Sweden)

    Shuying Li

    2014-09-01

    Full Text Available To our best knowledge, all of the fungal immunomodulatory proteins (FIPs have been successfully extracted and identified in Basidomycetes, with only the exception of FIP from ascomycete Nectria haematococca (FIP-nha discovered through homology alignment most recently. In this work, a gene encoding FIP-nha was synthesized and recombinantly expressed in an Escherichia coli expression system. SDS-PAGE and MALDI-MS analyses of recombinant FIP-nha (rFIP-nha indicated that the gene was successfully expressed. The yield of the bioactive FIP-nha protein was 42.7 mg/L. In vitro assays of biological activity indicated that the rFIP-nha caused hemagglutination of human and rabbit red blood cells, significantly stimulated mouse spleen lymphocyte proliferation, and enhanced expression of interleukin-2 (IL-2 released from mouse splenocytes, revealing a strong antitumor effect against HL60, HepG2 and MGC823. Through this work, we constructed a rapid and efficient method of FIP production, and suggested that FIP-nha is a valuable candidate for use in future medical care and pharmaceutical products.

  4. Monomer Adsorption-Desorption Processes

    Institute of Scientific and Technical Information of China (English)

    KE Jian-Hong; LIN Zhen-Quan; CHEN Xiao-Shuang

    2009-01-01

    We propose an adsorption-desorption model for a deposit growth system, in which the adsorption and desorption of particles coexist. By means of the generalized rate equation we investigate the cluster (island) size distribution in the dynamic equilibrium state. The results show that the evolution behaviour of the system depends crucially on the details of the rate kernels. The cluster size distribution can take the ecale-frse power-law form in some cases, while it grows exponentially with size in other cases.

  5. Data compilation for particle impact desorption

    International Nuclear Information System (INIS)

    The desorption of gases from solid surfaces by incident electrons, ions and photons is one of the important processes of hydrogen recycling in the controlled thermonuclear reactors. We have surveyed the literature concerning the particle impact desorption published through 1983 and compiled the data on the desorption cross sections and desorption yields with the aid of a computer. This report presents the results obtained for electron stimulated desorption, the desorption cross sections and yields being given in graphs and tables as functions of incident electron energy, surface temperature and gas exposure. (author)

  6. Thyroid dysfunction induced by recombinant interferon-alpha therapy for chronic active type C hepatitis

    International Nuclear Information System (INIS)

    The aim of this study was to assess the frequency and types of thyroid therapy in patients of Chronic dysfunction that develops during IFN- Hepatitis C. The study was carried out on a total of 50 patients of chronic therapy. In addition 50 patients with hepatitis C on recombinant IFN- chronic hepatitis C, not on any antiviral treatment, were included as controls. After informed consent, clinical history was obtained, physical examination was done and findings recorded on a pre-designed proforma. Blood sampling was done for thyroid profile at the beginning of interferon therapy, at 12 weeks and finally at 24 weeks. Thyroid dysfunction (TD) was observed in 14% (n=7) of the patients on antiviral therapy for CHC (n=50). Amongst these seven patients with TD, hypothyroidism was observed in 5 and hyperthyroidism in 2 patients. In contrast the frequency of thyroid dysfunction observed in control group (n=50) was 2%. The frequency of thyroid dysfunction in patients of chronic hepatitis C treated with interferon approaches 14%, with hypothyroidism being the more commonly observed pattern. (author)

  7. Anti-tumor efficacy of lymphokine-activated killer cells and recombinant interleukin 2 in vivo

    International Nuclear Information System (INIS)

    The authors showed previously that adoptive immunotherapy with the combination of LAK cells and recombinant IL 2 (RIL 2) can markedly reduce pulmonary micrometastases from multiple sarcomas established 3 days after the i.v. injection of syngeneic tumor cells in C57BL/6 mice. In this report, they analyzed the factors required for successful therapy. Titration analysis in vivo revealed an inverse relationship between the number of pulmonary metastases remaining after treatment and both the number of LAK cells and the amount of RIL 2 administered. Fresh or unstimulated splenocytes had no anti-tumor effect; a 2- to 3-day incubation of splenocytes in RIL 2 was required. LAK cells generated from allogeneic DBA (H-2d) splenocytes were as effective in vivo as syngeneic, C57BL/6 (H-2b) LAK cells. The anti-metastatic capacity of LAK cells was significantly reduced or eliminated when irradiated with 3000 rad before adoptive transfer. The combined therapy of LAK cells plus RIL 2 was shown to be highly effective in mice immunosuppressed by 500 rad total body irradiation and in treating macrometastases established in the lung 10 days after the i.v. injection of sarcoma cells. Further, reduction of both micrometastases and macrometastases could also be achieved by RIL 2 alone when administered at higher levels than were required with LAK cells. The value of LAK cell transfer and of IL 2 administration for the treatment of tumors established at other sites is currently under investigation

  8. Application of synchrotron-radiation-based x-ray microprobe techniques for the analysis of recombination activity of metals precipitated at Si/SiGe misfit dislocations

    Energy Technology Data Exchange (ETDEWEB)

    Vyvenko, O F [University of California, LBNL, 1 Cyclotron Rd, Berkeley, CA 94720 (United States); Buonassisi, T [University of California, LBNL, 1 Cyclotron Rd, Berkeley, CA 94720 (United States); Istratov, A A [University of California, LBNL, 1 Cyclotron Rd, Berkeley, CA 94720 (United States); Weber, E R [University of California, LBNL, 1 Cyclotron Rd, Berkeley, CA 94720 (United States); Kittler, M [IHP, Im Technologiepark 25, D-15236 Frankfurt (Oder) (Germany); Seifert, W [IHP, Im Technologiepark 25, D-15236 Frankfurt (Oder) (Germany)

    2002-12-09

    In this study we report application of synchrotron-radiation-based x-ray microprobe techniques (the x-ray-beam-induced current (XBIC) and x-ray fluorescence ({mu}-XRF) methods) to the analysis of the recombination activity and space distribution of copper and iron in the vicinity of dislocations in silicon/silicon-germanium structures. A combination of these two techniques enables one to study the chemical nature of the defects and impurities and their recombination activity in situ and to map metal clusters with a micron-scale resolution. XRF analysis revealed that copper formed clearly distinguishable precipitates along the misfit dislocations. A proportional dependence between the XBIC contrast and the number of copper atoms in the precipitates was established. In hydrogen-passivated iron-contaminated samples we observed clusters of iron precipitates which had no recombination activity detectable by the XBIC technique as well as iron clusters which were not completely passivated.

  9. Application of synchrotron-radiation-based x-ray microprobe techniques for the analysis of recombination activity of metals precipitated at Si/SiGe misfit dislocations

    CERN Document Server

    Vyvenko, O F; Istratov, A A; Weber, E R; Kittler, M; Seifert, W

    2002-01-01

    In this study we report application of synchrotron-radiation-based x-ray microprobe techniques (the x-ray-beam-induced current (XBIC) and x-ray fluorescence (mu-XRF) methods) to the analysis of the recombination activity and space distribution of copper and iron in the vicinity of dislocations in silicon/silicon-germanium structures. A combination of these two techniques enables one to study the chemical nature of the defects and impurities and their recombination activity in situ and to map metal clusters with a micron-scale resolution. XRF analysis revealed that copper formed clearly distinguishable precipitates along the misfit dislocations. A proportional dependence between the XBIC contrast and the number of copper atoms in the precipitates was established. In hydrogen-passivated iron-contaminated samples we observed clusters of iron precipitates which had no recombination activity detectable by the XBIC technique as well as iron clusters which were not completely passivated.

  10. Telomerase repeat amplification protocol (TRAP) activity upon recombinant expression and purification of human telomerase in a bacterial system.

    Science.gov (United States)

    Hansen, Debra T; Thiyagarajan, Thirumagal; Larson, Amy C; Hansen, Jeffrey L

    2016-07-01

    Telomerase biogenesis is a highly regulated process that solves the DNA end-replication problem. Recombinant expression has so far been accomplished only within a eukaryotic background. Towards structural and functional analyses, we developed bacterial expression of human telomerase. Positive activity by the telomerase repeat amplification protocol (TRAP) was identified in cell extracts of Escherichia coli expressing a sequence-optimized hTERT gene, the full-length hTR RNA with a self-splicing hepatitis delta virus ribozyme, and the human heat shock complex of Hsp90, Hsp70, p60/Hop, Hsp40, and p23. The Hsp90 inhibitor geldanamycin did not affect post-assembly TRAP activity. By various purification methods, TRAP activity was also obtained upon expression of only hTERT and hTR. hTERT was confirmed by tandem mass spectrometry in a ∼120 kDa SDS-PAGE fragment from a TRAP-positive purification fraction. TRAP activity was also supported by hTR constructs lacking the box H/ACA small nucleolar RNA domain. End-point TRAP indicated expression levels within 3-fold of that from HeLa carcinoma cells, which is several orders of magnitude below detection by the direct assay. These results represent the first report of TRAP activity from a bacterium and provide a facile system for the investigation of assembly factors and anti-cancer therapeutics independently of a eukaryotic setting. PMID:26965413

  11. Potential bone-inducing activity in vitro of recombinant human bone morphogenetic protein-7 from a CHO expression system

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-yan; SHI Wei-wei; WANG Hao; LI Bo-hua; YANG Yang; TAN Min; XUE Jing-ya; GUO Ya-jun

    2005-01-01

    Objective: To express the recombinant human bone morphogenetic protein-7 (rhBMP-7) in Chinese hamster ovary(CHO) cells, and to establish the in vitro biological activity assay of rhBMP-7.Methods: Human BMP-7 cDNA was subcloned into p114 mammalian expression vector and transfected to CHO cells by using the Lipofectamine2000 transfection method. CHO cell supernatants were harvested and analyzed to identify the molecule mass of secreted rhBMP-7 and examine its biological activity in vitro to stimulate the synthesis of alkaline phophatase(ALP), a characteristic of osteoblast phenotypes. Results:rhBMP-7 was produced stably in CHO cells, as a processed mature disulfide-linked homodimer, with an apparent molecular mass of 36 000. Examination of the rhBMP-7 biological activity showed that rhBMP-7 specifically stimulated the production of ALP(4-fold increase at 100 ng of rhBMP-7/ml). Conclusion: The rhBMP-7 from CHO expression system has significant biological activity in induction of osteoblast phenotype, which demonstrates rhBMP-7 has the potential bone regeneration activity.

  12. SPS Ion Induced Desorption Experiment

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    This experiment will give a study about the induced desorption from heavy ion (Indium ion run from week 45 in SPS T4-H8 area) impacting LHC type graphite collimator. 4 different samples are located in the 4 chambers 90° one to each other: pure graphite, graphite with copper coating, graphite with NEG coating, 316LN stainless steal (reference).

  13. Efficacy of recombinant tissue-type plasminogen activator thrombolysis and primary coronary stenting after acute myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    陈步星; 王伟民; 赵红; 胡大一; 徐成斌; 赵明中; 卢明瑜; 刘健; 吴淳

    2003-01-01

    Objective To compare the efficacy of low dose recombinant tissue-type plasminogen activator (rt-PA) thrombolysis with primary coronary stenting after acute myocardial infarction.Methods Of 261 patients with first acute myocardial infarction, 131 were given low dose rt-PA intravenous thrombolysis, and 130 primary coronary stenting.Results The age, time from onset of chest pain to hospital presentation and infarct location between these two groups were comparable. The patency rate of the infarct-related artery (IRA) in patients in the thrombolysis group was significantly lower than that of patients in the primary stenting group (P0.05).Conclusion Comparing with low dose rt-PA thrombolytic therapy after acute myocardial infarction, primary coronary stenting has a higher patency rate of the IRA, better cardiac function and shorter hospitalization time.

  14. Activity in mice of recombinant BCG-EgG1Y162 vaccine for Echinococcus granulosus infection.

    Science.gov (United States)

    Ma, Xiumin; Zhao, Hui; Zhang, Fengbo; Zhu, Yuejie; Peng, Shanshan; Ma, Haimei; Cao, Chunbao; Xin, Yan; Yimiti, Delixiati; Wen, Hao; Ding, Jianbing

    2016-01-01

    Cystic hydatid disease is a zoonotic parasitic disease caused by Echinococcus granulosus which is distributed worldwide. The disease is difficult to treat with surgery removal is the only cure treatment. In the high endemic areas, vaccination of humans is believed a way to protect communities from the disease. In this study we vaccinated BALB/c mice with rBCG-EgG1Y162, and then detected the level of IgG and IgE specifically against the recombinant protein by ELISA, rBCG-EgG1Y162 induced strong and specific cellular and humoral immune responses. In vitro study showed that rBCG-EgG1Y162 vaccine not only promote splenocytes proliferation but also active T cell. In addition, the rBCG-EgG1Y162 induced a protection in the mice against secondary infection of Echinococcus granulosus.

  15. A kinetic model describing cell growth and production of highly active, recombinant ice nucleation protein in Escherichia coli.

    Science.gov (United States)

    Palaiomylitou, M A; Matis, K A; Zouboulis, A I; Kyriakidis, D A

    2002-05-01

    A structured kinetic model, which describes the production of the recombinant ice nucleation protein in different conditions, was applied. The model parameters were estimated based on the variation of the specific growth rate and the intracellular product concentration during cultivation. The equations employed relate the cellular plasmid content or plasmid copy number with the cloned-gene expression; these correlations were successfully tested on the experimental data. The optimal nutrient conditions for the growth of Escherichia coli expressing the inaZ gene of Pseudomonas syringae were determined for the production of active ice nucleation protein. The kinetics of the cultures expressing the inaZ gene were studied in a bioreactor at different growth temperatures and nutrient conditions. PMID:11920448

  16. The level of glucose-6-phosphate dehydrogenase activity strongly influences xylose fermentation and inhibitor sensitivity in recombinant Saccharomyces cerevisiae strains

    DEFF Research Database (Denmark)

    Jeppsson, M.; Johansson, B.; Jensen, Peter Ruhdal;

    2003-01-01

    Disruption of the ZWF1 gene encoding glucose-6-phosphate dehydrogenase (G6PDH) has been shown to reduce the xylitol yield and the xylose consumption in the xylose-utilizing recombinant Saccharomyces cerevisiae strain TMB3255. In the present investigation we have studied the influence of different...... consumption, respectively, compared with the ZWF1-disrupted strain. Both strains exhibited decreased xylitol yields (0.13 and 0.19 g/g xylose) and enhanced ethanol yields (0.36 and 0.34 g/g xylose) compared with the control strain TMB3001 (0.29 g xylitol/g xylose, 0.31 g ethanol/g xylose). Cytoplasmic...... transhydrogenase (TH) from Azotobacter vinelandii has previously been shown to transfer NADPH and NAD(+) into NADP(+) and NADH, and TH-overproduction resulted in lower xylitol yield and enhanced glycerol yield during xylose utilization. Strains with low G6PDH-activity grew slower in a lignocellulose hydrolysate...

  17. Pyelolithotomy in a patient with Glanzmann thrombasthenia and antiglycoprotein IIb/IIIa antibodies: the shortest possible duration of treatment with recombinant activated factor VII and platelet transfusions.

    Science.gov (United States)

    Devecioğlu, Omer; Unüvar, Ayşegül; Anak, Sema; Bilge, Ilmay; Ander, Haluk; Ziylan, Orhan

    2003-01-01

    Transfusion of platelet concentrates remains the first-line therapy for Glanzmann thrombasthenia in case of bleeding or preparation for surgery. However, development of antibodies to platelet glycoprotein (Gp) IIb/IIIa complex or human leukocyte antigens (HLA) is frequent and the main cause of platelet refractoriness. Recombinant activated factor VII (rFVIIa) is a potent alternative for patients with Glanzmann thrombasthenia with anti-platelet antibodies. We describe a case of Glanzmann thrombasthenia with alloantibodies to platelet Gp IIb/IIIa complex who underwent a successful pyelolithotomy operation under the coverage of recombinant activated factor VIIa and platelet transfusions. PMID:12718376

  18. The Use of Low-Dose Recombinant Tissue Plasminogen Activator to Treat a Preterm Infant with an Intrauterine Spontaneous Arterial Thromboembolis

    Directory of Open Access Journals (Sweden)

    Yaşar Demirelli

    2015-12-01

    Full Text Available Neonatal thromboembolic events are rare, and only a few cases of intrauterine spontaneous arterial thromboembolisms have been reported in the literature. Thrombolytic therapy with recombinant tissue plasminogen activator is usually the preferred treatment because it has a short half-life, fewer systemic side effects, and a strong, specific affinity for fibrin. Protocols vary from center to center, but there is still no consensus regarding the proper dosage or treatment duration. Herein, we present the case of an intrauterine spontaneous arterial thromboembolism in a preterm infant that completely resolved after being treated with low-dose recombinant tissue plasminogen activator (0.02 mg/kg/h.

  19. Potency of Full- Length MGF to Induce Maximal Activation of the IGF-I R Is Similar to Recombinant Human IGF-I at High Equimolar Concentrations

    OpenAIRE

    Janssen, Joseph A. M. J. L.; Hofland, Leo J.; Strasburger, Christian J.; Elisabeth S R van den Dungen; Mario Thevis

    2016-01-01

    textabstractAims To compare full-length mechano growth factor (full-length MGF) with human recombinant insulin-like growth factor-I (IGF-I) and human recombinant insulin (HI) in their ability to activate the human IGF-I receptor (IGF-IR), the human insulin receptor (IR-A) and the human insulin receptor-B (IR-B), respectively. In addition, we tested the stimulatory activity of human MGF and its stabilized analog Goldspink-MGF on the IGF-IR. Methods The effects of full-length MGF, IGF-I, human ...

  20. Recombination instability

    DEFF Research Database (Denmark)

    D'Angelo, N.

    1967-01-01

    A recombination instability is considered which may arise in a plasma if the temperature dependence of the volume recombination coefficient, alpha, is sufficiently strong. Two cases are analyzed: (a) a steady-state plasma produced in a neutral gas by X-rays or high energy electrons; and (b...

  1. Impact of cysteine variants on the structure, activity, and stability of recombinant human α-galactosidase A.

    Science.gov (United States)

    Qiu, Huawei; Honey, Denise M; Kingsbury, Jonathan S; Park, Anna; Boudanova, Ekaterina; Wei, Ronnie R; Pan, Clark Q; Edmunds, Tim

    2015-09-01

    Recombinant human α-galactosidase A (rhαGal) is a homodimeric glycoprotein deficient in Fabry disease, a lysosomal storage disorder. In this study, each cysteine residue in rhαGal was replaced with serine to understand the role each cysteine plays in the enzyme structure, function, and stability. Conditioned media from transfected HEK293 cells were assayed for rhαGal expression and enzymatic activity. Activity was only detected in the wild type control and in mutants substituting the free cysteine residues (C90S, C174S, and the C90S/C174S). Cysteine-to-serine substitutions at the other sites lead to the loss of expression and/or activity, consistent with their involvement in the disulfide bonds found in the crystal structure. Purification and further characterization confirmed that the C90S, C174S, and the C90S/C174S mutants are enzymatically active, structurally intact and thermodynamically stable as measured by circular dichroism and thermal denaturation. The purified inactive C142S mutant appeared to have lost part of its alpha-helix secondary structure and had a lower apparent melting temperature. Saturation mutagenesis study on Cys90 and Cys174 resulted in partial loss of activity for Cys174 mutants but multiple mutants at Cys90 with up to 87% higher enzymatic activity (C90T) compared to wild type, suggesting that the two free cysteines play differential roles and that the activity of the enzyme can be modulated by side chain interactions of the free Cys residues. These results enhanced our understanding of rhαGal structure and function, particularly the critical roles that cysteines play in structure, stability, and enzymatic activity. PMID:26044846

  2. Recombinant human bone morphogenetic protein-7 expressed from CHO cells possessing the activity of bone-induced in vitro

    Institute of Scientific and Technical Information of China (English)

    LI Xiaoyan; WANG Hao; YANG Yang; TAN Min; XUE Jingya; NI Haidong; GUO Yajun

    2006-01-01

    Objective To express the recombinant human bone morphogenetic protein-7 (rhBMP-7) in Chinese hamster ovary (CHO) cells and to establish the in vitro biological activity assay of rhBMP-7. Methods Human BMP-7 cDNA was subcloned into pcDNA3.1 mammalian expression vector and transfected to CHO cells by using the lipofectin transfection method. BMP-7 expression cell culture supernatants were harvested and purified for target protein. To analyze the bioactivity of the secreted rhBMP-7, a novel in vitro assay was established by measuring its alkaline phosphatase (ALP) stimulating of osteoblast cell line, W-20-17. Results BMP-7 stably expressing cell clone was selected, which secreted mature disulfide-linked homodimer form of hBMP-7 and had an apparent molecular weight of 36kDa. rhBMP-7 with >95% purity was obtained using 3 step chromatography method. Bioactivity assay showed that the purified protein specifically stimulated W-20-17 cell producing ALP, with a 4-fold increase of ALP activity at 100ng/ml or more, and the EC50 of 15.6ng/ml. Conclusion Purified rhBMP-7 from this CHO expression system has significant biological activity in induction of osteoblast phenotype, which demonstrates potential bone regeneration activity.

  3. Adjuvant Effects for Oral Immunization Provided by Recombinant Lactobacillus casei Secreting Biologically Active Murine Interleukin-1β▿

    OpenAIRE

    KAJIKAWA, Akinobu; MASUDA, Kazuya; Katoh, Mitsunori; Igimi, Shizunobu

    2009-01-01

    Vaccine delivery systems using lactic acid bacteria are under development, but their efficiency is insufficient. Autologous cytokines, such as interleukin-1β (IL-1β), are potential adjuvants for mucosal vaccines and can be provided by recombinant lactic acid bacteria. The aim of this study was the construction and evaluation of recombinant Lactobacillus casei producing IL-1β as an adjuvant delivery agent. The recombinant strain was constructed using an expression/secretion vector plasmid, inc...

  4. Expression and purification of recombinant human neuritin from Pichia pastoris and a partial analysis of its neurobiological activity in vitro.

    Science.gov (United States)

    Zhang, Yunhua; Zhang, Shujun; Xian, Lingling; Tang, Juan; Zhu, Jingling; Cui, Lijuan; Li, Shanman; Yang, Lei; Huang, Jin

    2015-10-01

    Neuritin (also known as candidate plasticity gene 15 (cpg15)) is a neurotrophic factor that was recently discovered in a screen aimed at identifying genes involved in activity-dependent synaptic plasticity. Neuritin plays multiple roles in both neural development (Chen et al. Zhonghua Yan Ke Za Zhi 46:978-983 2010; Corriveau et al. J Neurosci 19:7999-8008 1999; Lee and Nedivi J Neurosci 22:1807-1815 2002) and synaptic plasticity (Fujino et al. Gene Dev 25:2674-2685 2011; Leslie and Nedivi Prog 14 Neurobiol 94:223-237 2011; Loebrich and Nedivi Physiol Rev 89:1079 2009). In this study, to produce bioactive, soluble recombinant human neuritin protein, a portion of NRN1 was cloned into the Pichia pastoris expression vector pPIC9K. The recombinant vector was then transformed into the methylotrophic yeast strain P. pastoris GS115, and a shaking flask method and His-tag purification strategy were utilized to express and purify neuritin protein. The resulting protein had a molecular mass of approximately 11 kDa, and subsequent functional analyses indicated that the purified neuritin promoted neurite outgrowth from embryonic chicken dorsal root ganglions, while also prolonging the survival of these ganglions, and from PC12 cells. These findings suggest that neuritin was expressed effectively in vitro and that this protein may play a role in stimulating neurite outgrowth of both dorsal root ganglions and PC12 cells. This study provides a novel strategy for the large-scale production of bioactive neuritin, which will enable further study of the biological function of this protein. PMID:26048470

  5. Construction of recombinant adenovirus with Egr-1 promoter and Smad7 cDNA and study of the Egr-1 promoter's biological activity

    International Nuclear Information System (INIS)

    Objective: To construct a recombinant replication-defective adenovirus containing Egr-1 promoter and Smad7 cDNA, then to evaluate the biological activity of Egr-1 promoter. Methods: Based on Adeno- XTM expression system, CMV promoter of the pShuttle vector was replaced by Egr-1 promoter, and the Smad7 cDNA was subcloned into the MCS(multiple cloning site) of pShuttle. The recombinant pShuttle was then sub-cloned into the Adeno-XTM genome, which was transformed into E. coli to get recombinant Adeno-XTM plasmid DNA. The recombinant adenovirus was packaged and amplified in the transfected HEK293 cells before it was purified and tested for viral titer. The fibroblasts (3T6 cells) infected by the recombinant adenovirus were irradiated , and the activity of Egr-1 promoter was quantitively determined by the amount of Smad7 protein expressed in the 3T6 cells using Western blot. Results: Identified by restriction endonuclease analysis and PCR, the recombinant adenovirus containing Egr-1 promoter and Smad7 cDNA was constructed successfully, with a viral titer of 1.0 x 1011 TCID50/ml. The expressed amount of Smad7 protein varied at different dose levels and different time points post-irradiation in the 3T6 cells infected with the recombinant adenovirus. The amount of Smad7 protein increased along with the rising of the irradiation dose, and remained at a high expression level from 8 Gy to 15 Gy. The amount of Smad7 protein started to increase at 2 hours post-irradiation, and maintained a relatively high level for the next 5 hours before it descended, which was not observed in the control 3T6 cells. Conclusions: With the aid of Adeno-XTM expression system and molecular cloning techniques, construction of recombinant adenovirus could be quick and efficient. The recombined Egr-1 promoter has the activity of regulating the expression of downstream Smad7 cDNA. The increase in Smad7 expression under control of Egr-1 promoter induced by ionizing radiation is time- and dose

  6. Yeast homologous recombination-based promoter engineering for the activation of silent natural product biosynthetic gene clusters.

    Science.gov (United States)

    Montiel, Daniel; Kang, Hahk-Soo; Chang, Fang-Yuan; Charlop-Powers, Zachary; Brady, Sean F

    2015-07-21

    Large-scale sequencing of prokaryotic (meta)genomic DNA suggests that most bacterial natural product gene clusters are not expressed under common laboratory culture conditions. Silent gene clusters represent a promising resource for natural product discovery and the development of a new generation of therapeutics. Unfortunately, the characterization of molecules encoded by these clusters is hampered owing to our inability to express these gene clusters in the laboratory. To address this bottleneck, we have developed a promoter-engineering platform to transcriptionally activate silent gene clusters in a model heterologous host. Our approach uses yeast homologous recombination, an auxotrophy complementation-based yeast selection system and sequence orthogonal promoter cassettes to exchange all native promoters in silent gene clusters with constitutively active promoters. As part of this platform, we constructed and validated a set of bidirectional promoter cassettes consisting of orthogonal promoter sequences, Streptomyces ribosome binding sites, and yeast selectable marker genes. Using these tools we demonstrate the ability to simultaneously insert multiple promoter cassettes into a gene cluster, thereby expediting the reengineering process. We apply this method to model active and silent gene clusters (rebeccamycin and tetarimycin) and to the silent, cryptic pseudogene-containing, environmental DNA-derived Lzr gene cluster. Complete promoter refactoring and targeted gene exchange in this "dead" cluster led to the discovery of potent indolotryptoline antiproliferative agents, lazarimides A and B. This potentially scalable and cost-effective promoter reengineering platform should streamline the discovery of natural products from silent natural product biosynthetic gene clusters.

  7. Recombinant human interleukin 5 is a selective activator of human eosinophil function

    OpenAIRE

    1988-01-01

    Human rIL-5 was found to selectively stimulate morphological changes and the function of human eosinophils. This molecule is thus a prime candidate for the selective eosinophilia and eosinophil activation seen in disease.

  8. Effect of dexamethasone on peroxisome proliferator activated receptor-gamma mRNA expression in 3T3-L1 adipocytes with the human recombinant adiponectin

    Institute of Scientific and Technical Information of China (English)

    SHE Qi-mei; ZHAO Jing; WANG Xia-lian; ZHOU Chang-man; SHI Xian-zhong

    2007-01-01

    Background The fat derived protein adiponectin plays an important role in the regulation of glucose metabolism. The aim of this study was to provide the experimental basis for further investigating on adiponectin (ADPN) function. Its eukaryotic recombinant was constructed and expressed in precursor cells of 3T3-L1 adipocytes. The effects of dexamethasone on peroxisome proliferator activated receptor-gamma (PPAR-γ) mRNA expression in 3T3-L1 cells with human recombinant adiponectin were assessed. Methods The recombinant plasmid pMD18-T-hADPN and eukaryotic expression vector pcDNA3.1 + were digested by two restrictive endonucleases and adiponectin and linear pcDNA3.1+ were obtained. Then, they were ligated and translated into JM109. The recombinant pcDNA3.1+-hADPN so obtained was identified by digestion by restrictive endonuclease and nucleotide sequencing. The 3T3-L1 precursor cells were transfected using SuperFect Transfection Reagent (Qiagen). Furthermore, 3T3-L1 cells with human recombinant adiponectin incubated with dexamethasone (0.5 mmol/L) for 24 hours, cells were collected and total RNA was extracted. The PPAR-γ mRNA expression was quantified by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). Results After eukaryotic recombinant was digested by Hind Ⅲ and EcoR Ⅰ, fragments of 800 bp and 5.4 kb were identified by nucleotide sequence scanning and consistent with theoretical values. Electrophoretogram of RT-PCR in 3T3-L1 precursors showed only one band in front of 250 bp, which was consistent with theoretical value 234 bp. In the 3T3-L1 cells, 3T3-L1 cells with plasmid and 3T3-L1 cells human recombinant adiponectin, treatment with dexamethasone (0.5 mmol/L) decreased PPAR-γ mRNA expression compared to untreated controls (P<0.01). Effect of dexamethasone on PPAR-γ mRNA expression in 3T3-L1 cells was reversed by stably transfected human recombinant adiponectin.Conclusion The 3T3-L1 cells stably transfected human recombinant

  9. Increased volume of distribution for recombinant activated factor VII and longer plasma-derived factor VII half-life may explain their long lasting prophylactic effect

    NARCIS (Netherlands)

    Mathijssen, N.C.J.; Masereeuw, R.; Holme, P.A.; Kraaij, M.G.J. van; Laros, B.A.P.; Peyvandi, F.; Heerde, W.L. van

    2013-01-01

    INTRODUCTION: Prophylaxis with plasma-derived or recombinant activated factor VII is beneficial in severe factor VII deficiency. To understand why prophylactic treatment with both products is efficacious, we conducted a pharmacokinetic study. MATERIALS AND METHODS: Ten factor VII deficient patients

  10. Newly diagnosed congenital factor VII deficiency and utilization of recombinant activated factor VII (NovoSeven®

    Directory of Open Access Journals (Sweden)

    Bartosh NS

    2013-03-01

    Full Text Available Nicole S Bartosh, Tara Tomlin, Christian Cable, Kathleen HalkaDepartment of Internal Medicine, Division of Medical Oncology, Scott and White Healthcare and Texas A and M Health Science Center College of Medicine, Temple, TX, USAAbstract: This case report presents a newly diagnosed congenital factor VII deficiency treated with recombinant activated factor VII (rFVIIa. Congenital factor VII deficiency is a rare autosomal-recessive bleeding disorder that occurs in fewer than 1/500,000 persons. Its presentation can vary from epistaxis to hemarthroses and severe central nervous system bleeding, and correlates poorly with factor VII levels. Our patient had not had a significant hemostatic challenge prior to his presentation and therefore never had any symptomatology suggestive of this disease. He was treated with rFVIIa, and was able to undergo repair of his fractures without bleeding.Case report: A 19-year-old African-American male presented to the emergency room after an altercation that resulted in significant trauma. He sustained bilateral mandibular angle fractures and orbital floor fractures, requiring urgent surgical correction. On initial evaluation, he was noted to have a prolonged prothrombin time of 40.1 seconds, with an International Normalized Ratio of 4.0, a normal activated partial thromboplastin time of 29.9 seconds, and a platelet count of 241. After receiving vitamin K and fresh frozen plasma, he was taken to the operating room for a temporary rigid maxillomandibular fixation. A 1:1 mixing study with normal plasma corrected the prothrombin time (decreasing from 40.7 to 14.7 seconds and a factor VII assay revealed 5% of the normal factor VII level. The patient was diagnosed with congenital factor VII deficiency. Due to his coagulopathy and the extensive surgical correction needed, rFVIIa was administered and surgery was accomplished without hemorrhagic sequelae.Conclusion: This case report and review describes a rare congenital

  11. Effect of Ultrasound on Desorption Equilibrium

    Institute of Scientific and Technical Information of China (English)

    秦炜; 原永辉; 戴猷元

    2001-01-01

    Effects of ultrasound on intensification of separation process were investigated through the experiment of desorption equilibrium behavior. Tri-butyl phosphate (TBP) on NKA-X resin and phenol on a solvent impregnated resin, CL-TBP resin, were used for desorption processes. The desorption rate was measured with and without ultrasound. Desorption equilibrium was studied under various ultrasonic power densities or thermal infusion. Results showed that the desorption rate with ultrasound was much higher than that with normal thermal infusion. Both ultrasound and thermal infusion broke the desorption equilibrium existed at room temperature. However, after the systems were cooled down, the amount of solute desorbed in the liquid phase in the presence of ultrasound was much higher than that at the temperature corresponding to the same ultrasound power. It is proved that the initial desorption equilibrium was broken as a result of the spot energy effect of ultrasound.

  12. Human recombinant truncated RNASET2, devoid of RNase activity; A potential cancer therapeutic agent

    Science.gov (United States)

    Nesiel-Nuttman, Liron; Schwartz, Betty; Shoseyov, Oded

    2014-01-01

    Human RNASET2 has been implicated in antitumorigenic and antiangiogenic activities, independent of its ribonuclease capacities. We constructed a truncated version of human RNASET2, starting at E50 (trT2-50) and devoid of ribonuclease activity. trT2-50 maintained its ability to bind actin and to inhibit angiogenesis and tumorigenesis. trT2-50 binds to cell surface actin and formed a complex with actin in vitro. The antiangiogenic effect of this protein was demonstrated in human umbilical vein endothelial cells (HUVECs) by its ability to arrest tube formation on Matrigel, induced by angiogenic factors. Immunofluorescence staining of HUVECs showed nuclear and cytosolic RNASET2 protein that was no longer detectable inside the cell following trT2-50 treatment. This effect was associated with disruption of the intracellular actin network. trT2-50 co-localized with angiogenin, suggesting that both molecules bind (or compete) for similar cellular epitopes. Moreover, trT2-50 led to a significant inhibition of tumor development. Histological analysis demonstrated abundant necrotic tissue and a substantial loss of endothelial structure in trT2-50-treated tumors. Collectively, the present results indicate that trT2-50, a molecule engineered to be deficient of its catalytic activity, still maintained its actin binding and anticancer-related biological activities. We therefore suggest that trT2-50 may serve as a potential cancer therapeutic agent. PMID:25426551

  13. Neuronal targeting, internalization, and biological activity of a recombinant atoxic derivative of botulinum neurotoxin A

    Science.gov (United States)

    Botulinum neurotoxins (BoNT) have the unique capacity to cross epithelial barriers, target neuromuscular junctions, and translocate active metalloprotease component to the cytosol of motor neurons. We have taken advantage of the molecular carriers responsible for this trafficking to create a family ...

  14. Activities of wildtype and mutant p53 in suppression of homologous recombination as measured by a retroviral vector system

    Energy Technology Data Exchange (ETDEWEB)

    Lu Xiongbin; Lozano, Guillermina; Donehower, Lawrence A

    2003-01-28

    DNA repair of double strand breaks, interstrand DNA cross-links, and other types of DNA damage utilizes the processes of homologous recombination and non-homologous end joining to repair the damage. Aberrant homologous recombination is likely to be responsible for a significant fraction of chromosomal deletions, duplications, and translocations that are observed in cancer cells. To facilitate measurement of homologous recombination frequencies in normal cells, mutant cells, and cancer cells, we have developed a high titer retroviral vector containing tandem repeats of mutant versions of a GFP-Zeocin resistance fusion gene and an intact neomycin resistance marker. Recombination between the tandem repeats regenerates a functional GFP-Zeo{sup R} marker that can be easily scored. This retroviral vector was used to assess homologous recombination frequencies in human cancer cells and rodent fibroblasts with differing dosages of wild type or mutant p53. Absence of wild type p53 stimulated spontaneous and ionizing radiation-induced homologous recombination, confirming previous studies. Moreover, p53{sup +/-} mouse fibroblasts show elevated levels of homologous recombination compared to their p53{sup +/+} counterparts following retroviral vector infection, indicating that p53 is haploinsufficient for suppression of homologous recombination. Transfection of vector-containing p53 null Saos-2 cells with various human cancer-associated p53 mutants revealed that these altered p53 proteins retain some recombination suppression function despite being totally inactive for transcriptional transactivation. The retroviral vector utilized in these studies may be useful in performing recombination assays on a wide array of cell types, including those not readily transfected by normal vectors.

  15. Antiviral activity of recombinant porcine surfactant protein A against porcine reproductive and respiratory syndrome virus in vitro.

    Science.gov (United States)

    Li, Lan; Zheng, Qisheng; Zhang, Yuanpeng; Li, Pengcheng; Fu, Yanfeng; Hou, Jibo; Xiao, Xilong

    2016-07-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) has caused significant economic losses in the swine industry worldwide. However, there is not an ideal vaccine to provide complete protection against PRRSV. Thus, the need for new antiviral strategies to control PRRSV still remains. Surfactant protein A (SP-A) belongs to the family of C-type lectins, which can exert antiviral activities. In this present study, we assessed the antiviral properties of recombinant porcine SP-A (RpSP-A) on PRRSV infection in Marc 145 cells and revealed its antiviral mechanism using a plaque assay, real-time qPCR, western blotting analysis and an attachment and penetration assay. Our results showed that RpSP-A could inhibit the infectivity of PRRSV in Marc 145 cells and could reduce the total RNA and protein level. The attachment assay indicated that RpSP-A in the presence of Ca(2+) could largely inhibit Marc 145 cell attachment; however, in the penetration assay, it was relatively inactive. Furthermore, our study suggested that virus progeny released from infected Marc145 cells were blocked by RpSP-A from infecting other cells. We conclude that RpSP-A has antiviral activity against PRRSV, most probably by blocking viral attachment and the cell-to-cell transmission pathway, and therefore, RpSP-A holds promise as a novel antiviral agent against PRRSV. PMID:27101074

  16. Mediator facilitates transcriptional activation and dynamic long-range contacts at the IgH locus during class switch recombination.

    Science.gov (United States)

    Thomas-Claudepierre, Anne-Sophie; Robert, Isabelle; Rocha, Pedro P; Raviram, Ramya; Schiavo, Ebe; Heyer, Vincent; Bonneau, Richard; Luo, Vincent M; Reddy, Janardan K; Borggrefe, Tilman; Skok, Jane A; Reina-San-Martin, Bernardo

    2016-03-01

    Immunoglobulin (Ig) class switch recombination (CSR) is initiated by the transcription-coupled recruitment of activation-induced cytidine deaminase (AID) to Ig switch regions (S regions). During CSR, the IgH locus undergoes dynamic three-dimensional structural changes in which promoters, enhancers, and S regions are brought to close proximity. Nevertheless, little is known about the underlying mechanisms. In this study, we show that Med1 and Med12, two subunits of the mediator complex implicated in transcription initiation and long-range enhancer/promoter loop formation, are dynamically recruited to the IgH locus enhancers and the acceptor regions during CSR and that their knockdown in CH12 cells results in impaired CSR. Furthermore, we show that conditional inactivation of Med1 in B cells results in defective CSR and reduced acceptor S region transcription. Finally, we show that in B cells undergoing CSR, the dynamic long-range contacts between the IgH enhancers and the acceptor regions correlate with Med1 and Med12 binding and that they happen at a reduced frequency in Med1-deficient B cells. Our results implicate the mediator complex in the mechanism of CSR and are consistent with a model in which mediator facilitates the long-range contacts between S regions and the IgH locus enhancers during CSR and their transcriptional activation.

  17. S-S synapsis during class switch recombination is promoted by distantly located transcriptional elements and activation-induced deaminase.

    Science.gov (United States)

    Wuerffel, Robert; Wang, Lili; Grigera, Fernando; Manis, John; Selsing, Erik; Perlot, Thomas; Alt, Frederick W; Cogne, Michel; Pinaud, Eric; Kenter, Amy L

    2007-11-01

    Molecular mechanisms underlying synapsis of activation-induced deaminase (AID)-targeted S regions during class switch recombination (CSR) are poorly understood. By using chromosome conformation capture techniques, we found that in B cells, the Emicro and 3'Ealpha enhancers were in close spatial proximity, forming a unique chromosomal loop configuration. B cell activation led to recruitment of the germline transcript (GLT) promoters to the Emicro:3'Ealpha complex in a cytokine-dependent fashion. This structure facilitated S-S synapsis because Smicro was proximal to Emicro and a downstream S region was corecruited with the targeted GLT promoter to Emicro:3'Ealpha. We propose that GLT promoter association with the Emicro:3'Ealpha complex creates an architectural scaffolding that promotes S-S synapsis during CSR and that these interactions are stabilized by AID. Thus, the S-S synaptosome is formed as a result of the self-organizing transcription system that regulates GLT expression and may serve to guard against spurious chromosomal translocations.

  18. Experiment on large scale plume interaction with a stratified gas environment resembling the thermal activity of a autocatalytic recombiner

    Energy Technology Data Exchange (ETDEWEB)

    Mignot, G.; Kapulla, R.; Paladino, D.; Zboray, R. [Thermal Hydraulics Laboratory, Nuclear Energy and Safety Dept., Paul Scherrer Institut, 5232 Villigen PSI (Switzerland)

    2012-07-01

    Computational Fluid Dynamics codes (CFD) are increasingly being used to simulate containment conditions after various transient accident scenarios. Consequently, the reliability of such codes must be tested against experimental data. Such validation experiments related to gas mixing and hydrogen transport within containment compartments addressing the effect of heat source are presented in this paper. The experiments were conducted in the large-scale thermal-hydraulics PANDA facility located at the Paul-Scherrer-Inst. (PSI) in Switzerland, in the frame of the OECD/SETH-2 project. A 10 kW electric heater simulating the thermal activity of the autocatalytic recombiner was activated at full power in a containment vessel at the top of which a thick helium layer is initially present. The hot plume interacts with the bottom of the helium layer which is slowly eroded until complete break up at 1350 s. After final erosion of the layer a strong temperature and concentration gradient is maintained in the vessel below the heater inlet as well as in the adjacent vessel below the interconnecting pipe. A detailed characterization of the operating heater suggests the presence of cold gas ingress at the outlet that affects the flow in the chimney. This can be of concern if present in a real PAR unit. (authors)

  19. Mediator facilitates transcriptional activation and dynamic long-range contacts at the IgH locus during class switch recombination

    Science.gov (United States)

    Thomas-Claudepierre, Anne-Sophie; Robert, Isabelle; Rocha, Pedro P.; Raviram, Ramya; Schiavo, Ebe; Heyer, Vincent; Bonneau, Richard; Luo, Vincent M.; Reddy, Janardan K.; Borggrefe, Tilman; Skok, Jane A.

    2016-01-01

    Immunoglobulin (Ig) class switch recombination (CSR) is initiated by the transcription-coupled recruitment of activation-induced cytidine deaminase (AID) to Ig switch regions (S regions). During CSR, the IgH locus undergoes dynamic three-dimensional structural changes in which promoters, enhancers, and S regions are brought to close proximity. Nevertheless, little is known about the underlying mechanisms. In this study, we show that Med1 and Med12, two subunits of the mediator complex implicated in transcription initiation and long-range enhancer/promoter loop formation, are dynamically recruited to the IgH locus enhancers and the acceptor regions during CSR and that their knockdown in CH12 cells results in impaired CSR. Furthermore, we show that conditional inactivation of Med1 in B cells results in defective CSR and reduced acceptor S region transcription. Finally, we show that in B cells undergoing CSR, the dynamic long-range contacts between the IgH enhancers and the acceptor regions correlate with Med1 and Med12 binding and that they happen at a reduced frequency in Med1-deficient B cells. Our results implicate the mediator complex in the mechanism of CSR and are consistent with a model in which mediator facilitates the long-range contacts between S regions and the IgH locus enhancers during CSR and their transcriptional activation. PMID:26903242

  20. Mediator facilitates transcriptional activation and dynamic long-range contacts at the IgH locus during class switch recombination.

    Science.gov (United States)

    Thomas-Claudepierre, Anne-Sophie; Robert, Isabelle; Rocha, Pedro P; Raviram, Ramya; Schiavo, Ebe; Heyer, Vincent; Bonneau, Richard; Luo, Vincent M; Reddy, Janardan K; Borggrefe, Tilman; Skok, Jane A; Reina-San-Martin, Bernardo

    2016-03-01

    Immunoglobulin (Ig) class switch recombination (CSR) is initiated by the transcription-coupled recruitment of activation-induced cytidine deaminase (AID) to Ig switch regions (S regions). During CSR, the IgH locus undergoes dynamic three-dimensional structural changes in which promoters, enhancers, and S regions are brought to close proximity. Nevertheless, little is known about the underlying mechanisms. In this study, we show that Med1 and Med12, two subunits of the mediator complex implicated in transcription initiation and long-range enhancer/promoter loop formation, are dynamically recruited to the IgH locus enhancers and the acceptor regions during CSR and that their knockdown in CH12 cells results in impaired CSR. Furthermore, we show that conditional inactivation of Med1 in B cells results in defective CSR and reduced acceptor S region transcription. Finally, we show that in B cells undergoing CSR, the dynamic long-range contacts between the IgH enhancers and the acceptor regions correlate with Med1 and Med12 binding and that they happen at a reduced frequency in Med1-deficient B cells. Our results implicate the mediator complex in the mechanism of CSR and are consistent with a model in which mediator facilitates the long-range contacts between S regions and the IgH locus enhancers during CSR and their transcriptional activation. PMID:26903242

  1. Recombinant Helicobacter pylori catalase

    Institute of Scientific and Technical Information of China (English)

    Yang Bai; Ya-Li Zhang; Jian-Feng Jin; Ji-De Wang; Zhao-Shan Zhang

    2003-01-01

    AIM: To construct a recombinant strain which highly expresses catalase of Helicobacter pylori(H.pylori) and assay the activity of H. pylori catalase.METHODS: The catalase DNA was amplified from H. pylori chromosomal DNA with PCR techniques and inserted into the prokaryotie expression vector pET-22b (+), and then was transformed into the BL21 (DE3) E. coli strain which expressed catalase recombinant protein. The activity of H.pylori catalase was assayed by the Beers & Sizers.RESULTS: DNA sequence analysis showed that the sequence of catalase DNA was the same as GenBank's research. The catalase recombinant protein amounted to 24.4 % of the total bacterial protein after induced with IPTG for 3 hours at 37 ℃ and the activity of H. pylori catalase was high in the BL21 (DE3) E. coli strain.CONCLUSION: A clone expressing high activity H. pylori catalase is obtained, laying a good foundation for further studies.

  2. Inhibitory activity of Filipendula ulmaria constituents on recombinant human histidine decarboxylase.

    Science.gov (United States)

    Nitta, Yoko; Kikuzaki, Hiroe; Azuma, Toshiaki; Ye, Yuan; Sakaue, Motoyoshi; Higuchi, Yoshiki; Komori, Hirohumi; Ueno, Hiroshi

    2013-06-01

    Histidine decarboxylase (HDC) catalyses the formation of histamine, a bioactive amine. Agents that control HDC activity are beneficial for treating histamine-mediated symptoms, such as allergies and stomach ulceration. We searched for inhibitors of HDC from the ethyl acetate extract of the petal of Filipendula ulmaria, also called meadowsweet. Rugosin D, rugosin A, rugosin A methyl ester (a novel compound), and tellimagrandin II were the main components; these 4 ellagitannins exhibited a non-competitive type of inhibition, with K(i) values of approximately 0.35-1 μM. These K(i) values are nearly equal to that of histidine methyl ester (K(i)=0.46 μM), an existing substrate analogue inhibitor. Our results show that food products contain potent HDC inhibitors and that these active food constituents might be useful for designing clinically available HDC inhibitors. PMID:23411280

  3. Efficacy and effectiveness of recombinant human activated protein C in severe sepsis of adults

    OpenAIRE

    Greiner, Wolfgang; Willich, Stefan N.; Roll, Stefanie; Müller-Nordhorn, Jaqueline; Schumacher, Helge Knut

    2007-01-01

    Introduction: Sepsis is defined as an invasion of microorganisms and/or their toxins into the blood associated the reaction of the organism to this invasion. Severe sepsis is a major cost driver in intensive care medicine. In Germany, prevalence data was assessed in the context of the German Prevalence Study. Severe sepsis has a prevalence of 35% in German intensive care units. Research questions: The following questions were analysed: is Drotrecogin alfa (activated) (DAA) effective in the tr...

  4. Sustained thrombolysis with DNA-recombinant tissue type plasminogen activator in rabbits

    International Nuclear Information System (INIS)

    Tissue type plasminogen activator (t-PA) is an effective thrombolytic agent in experimental animals. The duration of the thrombolytic effect of infused t-PA is unknown. The authors compared the duration of the thrombolytic effect of t-PA with streptokinase by measuring the lysis of 125I-fibrin-labeled thrombi in rabbit jugular veins at different times after a bolus injection of the fibrinolytic agents. The pharmacodynamics of both thrombolytic agents were determined in rabbits using a sensitive ex vivo fibrinolytic assay. Streptokinase and t-PA were given as a bolus dose of 15,000 U/kg. There was no detectable circulating fibrinolytic activity 30 minutes after the bolus dose of t-PA and 120 minutes after the bolus dose of streptokinase. The t-PA injection produced 34% thrombolysis at 30 minutes, 90% thrombolysis at 120 minutes, and 96% thrombolysis at 240 minutes. The streptokinase injection produced 17% thrombolysis at 30 minutes, 34% at 120 minutes, and 34% at 240 minutes. These observations indicate that the thrombolytic effect of t-PA is sustained beyond its time of clearance from the circulation whereas the thrombolytic effect of streptokinase closely parallels its activity in the circulation

  5. Recombinant complement receptor 2 radiolabeled with [99mTc(CO3]+: a potential new radiopharmaceutical for imaging activated complement.

    Directory of Open Access Journals (Sweden)

    Adam Badar

    Full Text Available We describe the design and synthesis of a new Tc-99m labeled bioconjugate for imaging activated complement, based on Short Consensus Repeats 1 and 2 of Complement Receptor 2 (CR2, the binding domain for C3d. To avoid non specific modification of CR2 and the potential for modifying lysine residues critical to the CR2/C3d contact surface, we engineered a new protein, recombinant CR2 (rCR2, to include the C-terminal sequence VFPLECHHHHHH, a hexahistidine tag (for site-specific radiolabeling with [(99mTc(CO(3(OH(2(3](+. The protein was characterized by N-terminal sequencing, SDS-PAGE and size exclusion chromatography. To test the function of the recombinant CR2, binding to C3d was confirmed by enzyme-linked immunosorbent assay (ELISA. The function was further confirmed by binding of rCR2 to C3d(+ red blood cells (RBC which were generated by deposition of human or rat C3d and analyzed by fluorescence microscopy and flow cytometry. The affinity of rCR2 for C3d(+, in presence of 150 mM NaCl, was measured using surface plasma resonance giving rise to a K(D≈500 nM. Radiolabeling of rCR2 or an inactive mutant of rCR2 (K41E CR2 or an unrelated protein of a similar size (C2A with [(99mTc(CO(3(OH(2(3](+ at gave radiochemical yields >95%. Site-specifically radiolabeled rCR2 bound to C3d to C3d(+ RBC. Binding of radiolabeled rCR2 to C3d was inhibited by anti-C3d and the radiolabeled inactive mutant K41E CR2 and C2A did not bind to C3d(+ RBCs. We conclude that rCR2-Tc(99m has excellent radiolabeling, stability and C3d binding characteristics and warrants in vivo evaluation as an activated complement imaging agent.

  6. TPM analyses reveal that FtsK contributes both to the assembly and the activation of the XerCD-dif recombination synapse.

    Science.gov (United States)

    Diagne, Cheikh Tidiane; Salhi, Maya; Crozat, Estelle; Salomé, Laurence; Cornet, Francois; Rousseau, Philippe; Tardin, Catherine

    2014-02-01

    Circular chromosomes can form dimers during replication and failure to resolve those into monomers prevents chromosome segregation, which leads to cell death. Dimer resolution is catalysed by a highly conserved site-specific recombination system, called XerCD-dif in Escherichia coli. Recombination is activated by the DNA translocase FtsK, which is associated with the division septum, and is thought to contribute to the assembly of the XerCD-dif synapse. In our study, direct observation of the assembly of the XerCD-dif synapse, which had previously eluded other methods, was made possible by the use of Tethered Particle Motion, a single molecule approach. We show that XerC, XerD and two dif sites suffice for the assembly of XerCD-dif synapses in absence of FtsK, but lead to inactive XerCD-dif synapses. We also show that the presence of the γ domain of FtsK increases the rate of synapse formation and convert them into active synapses where recombination occurs. Our results represent the first direct observation of the formation of the XerCD-dif recombination synapse and its activation by FtsK.

  7. Activation of the cellular unfolded protein response by recombinant adeno-associated virus vectors.

    Directory of Open Access Journals (Sweden)

    Balaji Balakrishnan

    Full Text Available The unfolded protein response (UPR is a stress-induced cyto-protective mechanism elicited towards an influx of large amount of proteins in the endoplasmic reticulum (ER. In the present study, we evaluated if AAV manipulates the UPR pathways during its infection. We first examined the role of the three major UPR axes, namely, endoribonuclease inositol-requiring enzyme-1 (IRE1α, activating transcription factor 6 (ATF6 and PKR-like ER kinase (PERK in AAV infected cells. Total RNA from mock or AAV infected HeLa cells were used to determine the levels of 8 different ER-stress responsive transcripts from these pathways. We observed a significant up-regulation of IRE1α (up to 11 fold and PERK (up to 8 fold genes 12-48 hours after infection with self-complementary (scAAV2 but less prominent with single-stranded (ssAAV2 vectors. Further studies demonstrated that scAAV1 and scAAV6 also induce cellular UPR in vitro, with AAV1 vectors activating the PERK pathway (3 fold while AAV6 vectors induced a significant increase on all the three major UPR pathways [6-16 fold]. These data suggest that the type and strength of UPR activation is dependent on the viral capsid. We then examined if transient inhibition of UPR pathways by RNA interference has an effect on AAV transduction. siRNA mediated silencing of PERK and IRE1α had a modest effect on AAV2 and AAV6 mediated gene expression (∼1.5-2 fold in vitro. Furthermore, hepatic gene transfer of scAAV2 vectors in vivo, strongly elevated IRE1α and PERK pathways (2 and 3.5 fold, respectively. However, when animals were pre-treated with a pharmacological UPR inhibitor (metformin during scAAV2 gene transfer, the UPR signalling and its subsequent inflammatory response was attenuated concomitant to a modest 2.8 fold increase in transgene expression. Collectively, these data suggest that AAV vectors activate the cellular UPR pathways and their selective inhibition may be beneficial during AAV mediated gene transfer.

  8. In plant activation: an inducible, hyperexpression platform for recombinant protein production in plants.

    Science.gov (United States)

    Dugdale, Benjamin; Mortimer, Cara L; Kato, Maiko; James, Tess A; Harding, Robert M; Dale, James L

    2013-07-01

    In this study, we describe a novel protein production platform that provides both activation and amplification of transgene expression in planta. The In Plant Activation (INPACT) system is based on the replication machinery of tobacco yellow dwarf mastrevirus (TYDV) and is essentially transient gene expression from a stably transformed plant, thus combining the advantages of both means of expression. The INPACT cassette is uniquely arranged such that the gene of interest is split and only reconstituted in the presence of the TYDV-encoded Rep/RepA proteins. Rep/RepA expression is placed under the control of the AlcA:AlcR gene switch, which is responsive to trace levels of ethanol. Transgenic tobacco (Nicotiana tabacum cv Samsun) plants containing an INPACT cassette encoding the β-glucuronidase (GUS) reporter had negligible background expression but accumulated very high GUS levels (up to 10% total soluble protein) throughout the plant, within 3 d of a 1% ethanol application. The GUS reporter was replaced with a gene encoding a lethal ribonuclease, barnase, demonstrating that the INPACT system provides exquisite control of transgene expression and can be adapted to potentially toxic or inhibitory compounds. The INPACT gene expression platform is scalable, not host-limited, and has been used to express both a therapeutic and an industrial protein.

  9. Antigenicity and Hemaglutination Activity of a Recombinant Hemagglutinin-Neuraminidase of Paramyxovirus Tianjin Strain

    Institute of Scientific and Technical Information of China (English)

    Mei LI; Li-jun YUAN; Li-ying SHI; Xiao-mian LI; Qing WANG; Wen-xiu WANG

    2008-01-01

    Paramyxovirus Tianjin strain, a new genotype of Sendal virus, was isolated from the lungs of common cotton-eared marmoset that died of severe respiratory infection in the marmoset colonies. The 19.28% IgM positive rate in the young children with acute respiratory tract infection suggested a close relationship between Tianjin strain and humans. Hemagglutinin-neuraminidase (HN) is its major transmembrane glycoprotein responsible for viral attachment, penetration and release. To clear the relationship between HN structure and function of paramyxovirus Tianjin strain, rHN1, rHN2 and rHN3 overlapping the ectodomain of HN protein were expressed. Their antigenicity and hemaglutination activity, as well as cross reactivity to standard antisera against influenza virus type A, type B were analyzed. The results indicated expressed rHNs have the natural antigenicity.The segment rHN2 possesses more linear epitopes exposed on the surface of the native I-IN protein than found in segments rHN3 and rHN1. The hemagglutination activity of segment rHN3 is higher than that of segments rHN2 and rHN1, and partially dependent on the three-dimensional conformation of HN3 protein. Cross-reactivity between rHNs and standard antisera against influenza virus type A, type B suggested that rHNs might not be the best alternative as specific antigens to detect virus in clinicalserum specimens.

  10. Nitrate sorption and desorption in biochars from fast pyrolysis

    Science.gov (United States)

    Increasing the nitrate (NO3-) sorption capacity of Midwestern US soils has the potential to reduce nitrate leaching to ground water and reduce the extent of the hypoxia zone in the Gulf of Mexico. The objective of this study was to determine the sorption and desorption capacity of non-activated and ...

  11. Myocardial infarction following recombinant tissue plasminogen activator treatment for acute ischemic stroke: a dangerous complication

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zhi-gang; WANG Rui-lan; YU Kang-long

    2012-01-01

    Thrombolysis with intravenous tissue plasminogen activator (t-PA) is currently an approved therapy for patients with acute ischemic stroke.Acute myocardial infarction (AMI) immediately following t-PA treatment for stroke is a rare but serious complication.A case of acute myocardial infarction (MI) following IV t-PA infusion for acute stroke was observed.This is a 52-year-old male with a known history of hypertension and chest pain,who subsequently developed MI four hours after IV t-PA was administered for acute ischemic stroke.The disruption of intra-cardiac thrombus and subsequent embolization to the coronary arteries may be an important mechanism.In addition.spontaneous recanalization of infarct-related arteries may be associated with 9reater myocardial salvage and better prognosis.

  12. [A case of successful thrombolysis by recombinant tissue plasminogen activator for postoperative pulmonary thromboembolism].

    Science.gov (United States)

    Inoue, Chiyo; Yano, Toshiyuki; Tashiro, Hironori; Terasaki, Hidenori

    2002-02-01

    A 52-year-old female suspected of hypercoagulability underwent modified radical hysterectomy and left oophorectomy for uterus cancer and left giant ovarian tumor under general combined with epidural anesthesia. On the day after the operation, the patient complained of dyspnea and developed tachypnea, a low Spo2, and hypotension after the intermittent external pneumatic compression of the legs. Echocardiography showed acute right cardiac failure and pulmonary angiography revealed massive pulmonary thromboembolism. The patient fell into shock with severe hypotension and unconsciousness during the catheter fragmentation and aspiration therapy for pulmonary thrombi. Bolus intravenous injection of monteplase 1.6 million units, a mutant of tissue plasminogen activator with a longer half-life, rapidly improved the shock status and stabilized the hemodynamic condition. Monteplase would be useful for life-threatening pulmonary thromboembolism although the risk of hemorrhagic complication remains.

  13. Recombinant Trichoderma harzianum endoglucanase I (Cel7B) is a highly acidic and promiscuous carbohydrate-active enzyme.

    Science.gov (United States)

    Pellegrini, Vanessa O A; Serpa, Viviane Isabel; Godoy, Andre S; Camilo, Cesar M; Bernardes, Amanda; Rezende, Camila A; Junior, Nei Pereira; Franco Cairo, João Paulo L; Squina, Fabio M; Polikarpov, Igor

    2015-11-01

    Trichoderma filamentous fungi have been investigated due to their ability to secrete cellulases which find various biotechnological applications such as biomass hydrolysis and cellulosic ethanol production. Previous studies demonstrated that Trichoderma harzianum IOC-3844 has a high degree of cellulolytic activity and potential for biomass hydrolysis. However, enzymatic, biochemical, and structural studies of cellulases from T. harzianum are scarce. This work reports biochemical characterization of the recombinant endoglucanase I from T. harzianum, ThCel7B, and its catalytic core domain. The constructs display optimum activity at 55 °C and a surprisingly acidic pH optimum of 3.0. The full-length enzyme is able to hydrolyze a variety of substrates, with high specific activity: 75 U/mg for β-glucan, 46 U/mg toward xyloglucan, 39 U/mg for lichenan, 26 U/mg for carboxymethyl cellulose, 18 U/mg for 4-nitrophenyl β-D-cellobioside, 16 U/mg for rye arabinoxylan, and 12 U/mg toward xylan. The enzyme also hydrolyzed filter paper, phosphoric acid swollen cellulose, Sigmacell 20, Avicel PH-101, and cellulose, albeit with lower efficiency. The ThCel7B catalytic domain displays similar substrate diversity. Fluorescence-based thermal shift assays showed that thermal stability is highest at pH 5.0. We determined kinetic parameters and analyzed a pattern of oligosaccharide substrates hydrolysis, revealing cellobiose as a final product of C6 degradation. Finally, we visualized effects of ThCel7B on oat spelt using scanning electron microscopy, demonstrating the morphological changes of the substrate during the hydrolysis. The acidic behavior of ThCel7B and its considerable thermostability hold a promise of its industrial applications and other biotechnological uses under extremely acidic conditions.

  14. Recombinant Trichoderma harzianum endoglucanase I (Cel7B) is a highly acidic and promiscuous carbohydrate-active enzyme.

    Science.gov (United States)

    Pellegrini, Vanessa O A; Serpa, Viviane Isabel; Godoy, Andre S; Camilo, Cesar M; Bernardes, Amanda; Rezende, Camila A; Junior, Nei Pereira; Franco Cairo, João Paulo L; Squina, Fabio M; Polikarpov, Igor

    2015-11-01

    Trichoderma filamentous fungi have been investigated due to their ability to secrete cellulases which find various biotechnological applications such as biomass hydrolysis and cellulosic ethanol production. Previous studies demonstrated that Trichoderma harzianum IOC-3844 has a high degree of cellulolytic activity and potential for biomass hydrolysis. However, enzymatic, biochemical, and structural studies of cellulases from T. harzianum are scarce. This work reports biochemical characterization of the recombinant endoglucanase I from T. harzianum, ThCel7B, and its catalytic core domain. The constructs display optimum activity at 55 °C and a surprisingly acidic pH optimum of 3.0. The full-length enzyme is able to hydrolyze a variety of substrates, with high specific activity: 75 U/mg for β-glucan, 46 U/mg toward xyloglucan, 39 U/mg for lichenan, 26 U/mg for carboxymethyl cellulose, 18 U/mg for 4-nitrophenyl β-D-cellobioside, 16 U/mg for rye arabinoxylan, and 12 U/mg toward xylan. The enzyme also hydrolyzed filter paper, phosphoric acid swollen cellulose, Sigmacell 20, Avicel PH-101, and cellulose, albeit with lower efficiency. The ThCel7B catalytic domain displays similar substrate diversity. Fluorescence-based thermal shift assays showed that thermal stability is highest at pH 5.0. We determined kinetic parameters and analyzed a pattern of oligosaccharide substrates hydrolysis, revealing cellobiose as a final product of C6 degradation. Finally, we visualized effects of ThCel7B on oat spelt using scanning electron microscopy, demonstrating the morphological changes of the substrate during the hydrolysis. The acidic behavior of ThCel7B and its considerable thermostability hold a promise of its industrial applications and other biotechnological uses under extremely acidic conditions. PMID:26156238

  15. Potentiation of mitomycin C and porfiromycin antitumor activity in solid tumor models by recombinant human interleukin 1 alpha.

    Science.gov (United States)

    Braunschweiger, P G; Jones, S A; Johnson, C S; Furmanski, P

    1991-10-15

    The time- and dose-dependent effects of recombinant human interleukin 1 alpha (IL-1 alpha) on the antitumor activity of mitomycin C (MMC) and porfiromycin (PORF) were studied in RIF-1 and Panc02 solid tumor model systems. IL-1 alpha produced dose-dependent sensitization of clonogenic RIF-1 tumor cells to MMC in vivo. IL-1 alpha chemosensitization was highly schedule dependent, and the most efficacious schedules produced dose-modifying factors of 3.6 and 5.1 for MMC and PORF, respectively. More than additive clonogenic cell kill after IL-1 alpha-chemotherapy combinations reflected increased cellular sensitivity to MMC and PORF. The combinations also produced marked decreases in the yield of viable tumor cells, suggesting that the bioreductive drugs may have also potentiated the microvascular injury and ischemia produced by IL-1 alpha. Dexamethasone inhibited and ketoconazole, an inhibitor of corticosterone biosynthesis, enhanced IL-1 alpha-mediated chemosensitization in these models. IL-1 alpha mediated chemosensitization to MMC, and PORF was also demonstrated by tumor growth inhibition in the RIF-1 model and increased survival of mice in the spontaneously metastasizing Panc02 system. Chemosensitization of bone marrow spleen colony-forming units was not seen. IL-1 alpha (1000 units/ml) had no effect on MMC and PORF cytotoxicity in RIF-1 and PORF cell lines in vitro. The results indicate that the tumor-specific IL-1 alpha-induced pathophysiologies can sensitize solid tumors to agents which are preferentially activated, retained, and cytotoxic to cells under hypoxic conditions. Our results suggest that strategies combining bioreductively activated hypoxic cell cytotoxins and biological agents might offer efficacious alternatives or adjuvants to conventional combination approaches. PMID:1913664

  16. ALMA observations of the submillimetre hydrogen recombination line from the type 2 active nucleus of NGC 1068

    Science.gov (United States)

    Izumi, Takuma; Nakanishi, Kouichiro; Imanishi, Masatoshi; Kohno, Kotaro

    2016-07-01

    Hydrogen recombination lines at the submillimetre band (submm-RLs) can serve as probes of ionized gas without dust extinction. One therefore expects to probe the broad-line region (BLR) of an obscured (type 2) active galactic nucleus (AGN) with those lines. However, admitting the large uncertainty in the continuum level, here we report on the non-detection of both broad and narrow H26 α emission line (rest frequency = 353.62 GHz) towards the prototypical type 2 AGN of NGC 1068 with the Atacama Large Millimeter/submillimeter Array (ALMA). We also investigate the nature of BLR clouds that can potentially emit submm-RLs with model calculations. As a result, we suggest that clouds with an electron density (Ne) of ˜109 cm-3 can mainly contribute to broad submm-RLs in terms of the line flux. On the other hand, line flux from other density clouds would be insignificant considering their too large or too small line optical depths. However, even for the case of Ne ˜ 109 cm-3 clouds, we also suggest that the expected line flux is extremely low, which is impractical to detect even with ALMA.

  17. Intraocular Lens Opacification following Intracameral Injection of Recombinant Tissue Plasminogen Activator to Treat Inflammatory Membranes after Cataract Surgery

    Directory of Open Access Journals (Sweden)

    Simon S. M. Fung

    2015-01-01

    Full Text Available Purpose. To report 7 cases of intraocular lens (IOL opacification following treatment of postoperative anterior chamber fibrin with recombinant tissue plasminogen activator (rtPA after cataract surgery. Methods. Retrospective case series of 7 eyes in 7 patients who developed IOL opacification after receiving rtPA for anterior chamber inflammatory membrane formation resulting from phacoemulsification cataract surgery. Three explanted IOLs were investigated with light microscopy, histochemical analysis, scanning electron microscopy, and X-ray spectrometry. Results. All patients underwent uncomplicated cataract surgery and posterior chamber hydrophilic IOL implantation. Anterior chamber inflammatory membranes developed between 1 and 4 weeks of surgery and were treated with intracameral rtPA. IOL opacification was noted between 4 weeks and 6 years after rtPA treatment with reduced visual acuity, and IOL exchange was carried out in 3 patients. Light microscopy evaluation revealed diffuse fine granular deposits on the anterior surface/subsurface of IOL optic that stained positive for calcium salts. Scanning electron microscopy (SEM and energy-dispersive X-ray spectrometry (EDS confirmed the presence of calcium and phosphate on the IOL. Conclusions. Intracameral rtPA, though rapidly effective in the treatment of anterior chamber inflammatory membranes following cataract surgery, may be associated with IOL opacification.

  18. Hemothorax under thrombolytic therapy with recombinant tissue: plasminogen activator (rt-PA) in a 16-year-old girl.

    Science.gov (United States)

    Varnholt, V; Ringe, H; Nietsch, L; Gaedicke, G

    1999-12-01

    We present the case of a 16-year-old girl with an extended thrombosis of the femoral and iliac vein and the inferior vena cava during pleuropneumonia; predisposing risk factors for thrombophilia were: use of contraceptives, nicotine abuse and congenital deficiency of antithrombin III (not previously diagnosed). Thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA; initial dose: 0.08 mg/kg/h) was started. 2 days later--after diagnosis of an extended hemothorax: 1500 ml blood were obtained after thoracocentesis, transfusion of packed red blood cells was necessary--rt-PA was stopped, with only heparin (400 U/kg/d) being administered. 36 h later--the thrombosis had not yet changed--the thrombolytic therapy with rt-PA was continued in a markedly reduced dose (0.015 mg/kg/d) with no further bleeding complications. 8 days later--after successful thrombolysis--t-PA was stopped, heparin was given for another 10 days, then cumarin was administered orally. PMID:10650854

  19. The Expression of Soluble and Active Recombinant Haemophilus influenzae IgA1 Protease in E. coli

    Directory of Open Access Journals (Sweden)

    Shinong Long

    2010-01-01

    Full Text Available Immunoglobulin A1 (IgA1 proteases from Haemophilus influenzae are extracellular proteases that specifically cleave the hinge region of human IgA1, the predominant class of immunoglobulin present on mucosal membranes. The IgA1 proteases may have the potential to cleave IgA1 complexes in the kidney and be a therapeutic agent for IgA1 nephropathy (IgAN, a disease characterized by deposition of the IgA1 antibody in the glomerulus. We have screened for the expression of recombinant H. influenzae IgA1 protease by combining various expression plasmids, IgA1 protease constructs, and E. coli strains under multiple conditions. Using the method we have developed, approximately 20–40 mg/L of soluble and active H. influenzae IgA1 protease can be produced from E. coli strain C41(DE3, a significant increase in yield compared to the yield upon expression in H. influenzae or other related bacteria.

  20. Recombinant hamster oviductin is biologically active and exerts positive effects on sperm functions and sperm-oocyte binding.

    Directory of Open Access Journals (Sweden)

    Xiaojing Yang

    Full Text Available Studies carried out in several mammalian species suggest that oviductin, also known as oviduct-specific glycoprotein or OVGP1, plays a key role in sperm capacitation, fertilization, and development of early embryos. In the present study, we used recombinant DNA technology to produce, for the first time, recombinant hamster OVGP1 (rHamOVGP1 in human embryonic kidney 293 (HEK293 cells. rHamOVGP1 secreted in the culture medium was purified by affinity chromatography. The resulting protein migrated as a poly-dispersed band of 160-350 kDa on SDS-PAGE corresponding to the molecular mass of the native HamOVGP1. Subsequent mass spectrometric analysis of the purified rHamOVGP1 confirmed its identity as HamOVGP1. Immunocytochemistry demonstrated binding of rHamOVGP1 to the mid-piece and head of hamster sperm and to the zona pellucida (ZP of ovarian oocytes. In vitro functional experiments showed that addition of rHamOVGP1 in the capacitation medium further enhanced tyrosine phosphorylation of two sperm proteins of approximately 75 kDa and 83 kDa in a time-dependent manner. After 3 hours of incubation in the presence of rHamOVGP1, a significant increase in acrosome reaction was measured. Pretreatment of either sperm or oocyte with 20 μg/ml of rHamOVGP1 prior to sperm-egg binding assay significantly increased the number of sperm bound to the ZP. Addition of rHamOVGP1 in the medium during sperm-egg binding with either oocyte or sperm pretreated with rHamOVGP1 also saw an increase in the number of sperm bound to ZP. In all experimental conditions, the effect of rHamOVGP1 on sperm-oocyte binding was negated by the addition of monoclonal anti-HamOVGP1 antibody. The successful production and purification of a biologically active rHamOVGP1 will allow further exploration of the function of this glycoprotein in reproductive function.

  1. Recombinant human erythropoietin reduces plasminogen activator inhibitor and ameliorates pro-inflammatory responses following trauma

    Directory of Open Access Journals (Sweden)

    M Mojtahedzadeh

    2011-05-01

    Full Text Available "n  "n Background and the purpose of the study: Besides its hematopoietic effects, erythropoietin (EPO by mobilization of iron and modulation of some inflammatory cytokines has antioxidant and anti-inflammatory properties. The purpose of this study was to evaluate these effects of erythropoietin and its impact on organ function in traumatized patients. "n Methods: Twenty-six ICU-admitted traumatized patients within 24 hrs after trauma were randomly assigned to the EPO (received EPO, 300 units/Kg/day and Control (not received EPO groups. The inflammatory biomarkers including Tumor Necrosis Factor alpha (TNF-α, Interleukin 1 (IL-1, Plasminogen Activator Inhibitor 1 (PAI-1 and Nitrotyrosine were recorded at the admission, 3, 6 and 9 days thereafter. Acute Physiology and Chronic Health Evaluation (APACHE II and Sequential Organ Failure Assessment (SOFA scores were also recorded. "n Results: Among 12 patients (EPO group TNF-α level at the day of 9 (P=0.046, and within EPO group at the days of 3 (P=0.026 ameliorate, 6 (P=0.016, and 9 (P=0.052 were significantly lowered. Level of IL-1 and PAI-1 decreased significantly at days of 3, 6 and 9 post intervention. Also there were significant differences between two groups in the SOFA score during three measured time intervals (the first, third and seventh days. "n Conclusion: From the results of this study it seems that injection of erythrocyte stimulating agent is well tolerated and inhibits the inflammatory response and oxidative stress following trauma.

  2. Phase I trial with recombinant interleukin-2 (rIL-2): immune activation by rIL-2 alone or following pretreatment with recombinant interferon-gamma.

    Science.gov (United States)

    Farace, F; Mathiot, C; Brandely, M; Tursz, T; Dorval, T; Pouillart, P; Triebel, F; Hercend, T; Fridman, W H

    1990-01-01

    Alterations of immunological parameters were analysed in patients with advanced malignancies during a phase I trial with rIL-2. Five-day infusions of rIL-2 at doses from 1 x 10(6) to 24 x 10(6) biological response modifiers program (BRMP) U/m2 per day were given to 29 patients, with a minimum of three patients per dose. The dose of 24 x 10(6) U/m2 per day was the maximal tolerated dose (MTD). Immunological parameters were analyzed at days 0, 8 and 11 of the rIL-2 courses. Following a leucopenia during rIL-2 infusion, a lymphocytosis was found in all patients except one. The lymphocytosis peaked at day 8 and was detected at doses of rIL-2 as low as 1 x 10(6) U/m2 per day, reaching a plateau at a dose of 16 x 10(6) U/m2 per day. Although all lymphocyte subsets were increased in patients receiving rIL-2, some patients had predominant T cells (CD3+, NKH1(CD56)-), others had predominant natural killer (NK) cells (CD3-, NKH1 (CD56)+), and yet others showed a mixed profile. A strong induction of cells cytotoxic for K562 targets was found in all patients at days 8 and 11. Eighteen patients received, 1 month later, a second treatment in which infusion of rIL-2 was preceded by a course of 5 days infusion of 2 x 10(6) U/m2 per day recombinant interferon-gamma (rIFN-gamma). The infusion of rIFN-gamma prior to rIL-2 had no effect on the rIL-2-induced alterations of immunological parameters. Taken together, our results suggest that immune stimulation by rIL-2 occurs even at low doses and is maximal at a dose below the MTD; and that pretreatment with low-dose rIFN-gamma does not modify the immune stimulation by rIL-2. PMID:2122928

  3. Calculation of activation energies for transport and recombination in mesoporous TiO2/dye/electrolyte films--taking into account surface charge shifts with temperature.

    Science.gov (United States)

    O'Regan, Brian C; Durrant, James R

    2006-05-01

    Transient photovoltage and photocurrent measurements have been employed to determine the recombination and transport kinetics in operating dye-sensitized photovoltaic cells as a function of potential and temperature. Photocurrent transients have been taken at the open circuit potential, as opposed to the standard measurement at short circuit. Kinetic results have been used to calculate the activation energy as function of the Fermi level position in the TiO(2). In the calculation of activation energies, we have explicitly taken into account the temperature dependence of the offset between the electrolyte redox potential and the conduction band edge. This new method gives activation energies that decrease linearly as the Fermi level position moves toward the conduction band edge, as expected, but not found in previous studies. The results are consistent with the presence of a distribution of traps below the TiO(2) conduction band, the detrapping from which limits both the transport and the recombination of electrons. PMID:16640403

  4. Efficacy and effectiveness of recombinant human activated protein C in severe sepsis of adults

    Directory of Open Access Journals (Sweden)

    Greiner, Wolfgang

    2007-07-01

    Full Text Available Introduction: Sepsis is defined as an invasion of microorganisms and/or their toxins into the blood associated the reaction of the organism to this invasion. Severe sepsis is a major cost driver in intensive care medicine. In Germany, prevalence data was assessed in the context of the German Prevalence Study. Severe sepsis has a prevalence of 35% in German intensive care units. Research questions: The following questions were analysed: is Drotrecogin alfa (activated (DAA effective in the treatment of patients with severe sepsis and a mixed risk of death, both in all patients and in different subgroups? Is DAA effective in the treatment of patients with severe sepsis and low risk of death? Is DAA cost effective in the treatment of patients with severe sepsis compared to placebo? Methods: Only studies with adult patients are included. There are no other exclusion criteria. A systematic literature search is performed by the German Institute of Medical Documentation and Information (DIMDI. The literature search yielded as a total of 847 hits. After screening of the abstracts, 165 medical and 101 economic publications were chosen for full text appraisal. Results: Therapy with DAA appears to be cost effective in reducing 28-day-mortality in patients with severe sepsis and a high risk of death. A high risk of death is indicated by the presence of multiorgan failure (≥2 and/or an APACHE-II-Score ≥25. Therapy with DAA is not associated with a long-term reduction of mortality at later follow-up assessments. Therapy with DAA is not associated with a long-term reduction of mortality at later follow-up assessments. Therapy with DAA is cost-effective in patients with multiorgan failure and/or an APACHE II Score (≥25. In patients with a lower risk of death, DAA is not cost-effective. Costs associated with bleeding events have been rarely included in cost calculations. Discussion: DAA appears to reduce mortality in patients with severe sepsis and a high

  5. Effects of single N-glycosylation site knockout on folding and defibrinogenating activities of acutobin recombinants from HEK293T.

    Science.gov (United States)

    Tsai, Inn-Ho; Wang, Ying-Ming; Huang, Kai-Fa

    2015-02-01

    Acutobin, the α-fibrinogenase from Deinagkistrodon acutus venom, contains four N-glycosylation sites with disialylated complex-typed glycans. Here, we explore the functional roles of each of the N-glycan by site-directed mutagenesis. The wild-type (ATB-wt) and single glycan-knockout mutants of recombinant acutobin were prepared from HEK293T, demonstrating that mutations at Asn(77), Asn(81) and Asn(100) impaired the folding while the S79A mutant and various Asn(229)-deglycosylated mutants were correctly folded. Based on homology modeling of acutobin and multiple sequence alignment with various venom thrombin-like enzymes, the importance of a hydrophilic environment at each glycosylation site to the enzyme folding could be rationalized. Remarkably, all the mutants showed similar catalytic activities for the chromogenic substrate and similar thermal stabilities as ATB-wt, suggesting that the glycan knockout did not affect the gross conformation and stability of the active sites. Although SDS-PAGE analyses revealed that ATB-wt and the D229-mutant degraded all human fibrinogen subunits faster but less specifically in vitro as compared with other mutants that cleaved only the α-subunit, ATB-wt and D229-mutant were not able to release fibrinogen-peptide A and thus coagulated human plasma slower than the other mutants did. In the mice model, the defibrinogenating effect of ATB-wt was stronger and lasting-longer than those of all the mutants. Taken together, all the glycans contribute to the pharmacokinetics of acutobin and ATB-wt in vivo, and the microenvironment around the Asn(229)-glycan appears to regulate the fibrinogen-chain specificity of acutobin while the N-glycans at positions 77, 81 and 100 are crucial for its folding. PMID:25533529

  6. Effect of recombinant human erythropoietin administration on lipid peroxidation and antioxidant enzyme(s activities in preterm infants.

    Directory of Open Access Journals (Sweden)

    Akisu M

    2001-12-01

    Full Text Available In the present investigation, we studied the effect of recombinant human erythropoietin (r-HuEPO on serum malondialdehyde (MDA as an index of lipid peroxidation, related to iron-catalyzed free radical reaction and erythrocyte superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GPX activities in very-low-birth weight (VLBW infants. Forty premature infants, at gestational ages were less than 33 weeks and birthweights were less than 1,500 g, were enrolled in the study. The study population was randomly divided into 2 groups. Twenty infants in Group 1 (treatment group were given r-HuEPO, and 20 infants in Group 2 served as the control. r-HuEPO treatment (750 U/kg a week was initiated on the 10th day of life and continued for 6 weeks. Preterm infants given erythrocyte transfusions during the study were excluded from the results. Serum ferritin and MDA levels, and erythrocyte superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GPX activities were analyzed at the end of the first week of life (at the beginning of the study. Subsequently, serum ferritin, and MDA levels were measured at the end of the 3rd and the 6th week. SOD, CAT, and GPX activities in the hemolysate were analyzed at the end of the 4th week. Six infants in the control group and 1 infant in the r-HuEPO group received transfusions through the end of the study, and these infants were excluded from the results. Significantly decreased serum ferritin concentrations were found in the r-HuEPO group compared to those in the control group both at the end of the 3rd and the 6th week (P < 0.05, and P < 0.01, respectively. In addition, serum MDA levels were also significantly reduced in Group 1 compared to control both at the end of the 3rd and the 6th week (P < 0.01 and P < 0.05, respectively. A good correlation was found between serum MDA and ferritin levels in Group 1. When the 2 groups were compared with respect to activities of SOD, CAT, and GPX at the end

  7. Spatially resolved thermal desorption/ionization coupled with mass spectrometry

    Science.gov (United States)

    Jesse, Stephen; Van Berkel, Gary J; Ovchinnikova, Olga S

    2013-02-26

    A system and method for sub-micron analysis of a chemical composition of a specimen are described. The method includes providing a specimen for evaluation and a thermal desorption probe, thermally desorbing an analyte from a target site of said specimen using the thermally active tip to form a gaseous analyte, ionizing the gaseous analyte to form an ionized analyte, and analyzing a chemical composition of the ionized analyte. The thermally desorbing step can include heating said thermally active tip to above 200.degree. C., and positioning the target site and the thermally active tip such that the heating step forms the gaseous analyte. The thermal desorption probe can include a thermally active tip extending from a cantilever body and an apex of the thermally active tip can have a radius of 250 nm or less.

  8. A soil-column gas chromatography (SCGC) approach to explore the thermal desorption behavior of hydrocarbons from soils.

    Science.gov (United States)

    Yu, Ying; Liu, Liang; Shao, Ziying; Ju, Tianyu; Sun, Bing; Benadda, Belkacem

    2016-01-01

    A soil-column gas chromatography approach was developed to simulate the mass transfer process of hydrocarbons between gas and soil during thermally enhanced soil vapor extraction (T-SVE). Four kinds of hydrocarbons-methylbenzene, n-hexane, n-decane, and n-tetradecane-were flowed by nitrogen gas. The retention factor k' and the tailing factor T f were calculated to reflect the desorption velocities of fast and slow desorption fractions, respectively. The results clearly indicated two different mechanisms on the thermal desorption behaviors of fast and slow desorption fractions. The desorption velocity of fast desorption fraction was an exponential function of the reciprocal of soil absolute temperature and inversely correlated with hydrocarbon's boiling point, whereas the desorption velocity of slow desorption fraction was an inverse proportional function of soil absolute temperature, and inversely proportional to the log K OW value of the hydrocarbons. The higher activation energy of adsorption was found on loamy soil with higher organic content. The increase of carrier gas flow rate led to a reduction in the apparent activation energy of adsorption of slow desorption fraction, and thus desorption efficiency was significantly enhanced. The obtained results are of practical interest for the design of high-efficiency T-SVE system and may be used to predict the remediation time. PMID:26335523

  9. Adsorption, reaction and desorption of hydrogen on modified Pd(1 1 1) surfaces

    International Nuclear Information System (INIS)

    The interaction of hydrogen (deuterium) with different modified Pd(1 1 1) surfaces has been investigated. The focus was put on the energy and angel dependence of the desorbing molecules from oxygen covered, potassium covered and vanadium oxide covered surfaces. Conventional adsorption/desorption as well as permeation/desorption experiments were performed. For the oxygen covered surface optimum reaction rates for water production and the energy distribution of the reaction products were determined, both for the reaction of oxygen with molecular hydrogen as well as with atomic hydrogen. Potassium on the surface enhances the activation barrier for hydrogen adsorption resulting in a hyper-thermal desorption flux and a forward focused angular distribution of desorption. Permeation/desorption of deuterium from ultra-thin vanadium oxide films yield mainly thermalized desorbing molecules or slightly hyper-thermal, depending on the oxidation state of the surface oxide.

  10. The unsialylated subpopulation of recombinant activated factor VII binds to the asialo-glycoprotein receptor (ASGPR) on primary rat hepatocytes.

    Science.gov (United States)

    Seested, Torben; Nielsen, Hanne M; Christensen, Erik I; Appa, Rupa S

    2010-12-01

    Recombinant activated factor VII (rFVIIa; NovoSeven®) is a heterogeneously glycosylated serine protease used for treatment of haemophiliacs with inhibitors. The drug substance contains a subpopulation consisting of ~20% of rFVIIa molecules which are unsialylated and consists of carbohydrate moieties with terminally exposed galactose and N-acetyl-D-galactosamine (GalNAc). Recently, data from an in situ perfused liver model showed that a subpopulation of rFVIIa, appearing to be unsialylated rFVIIa, was cleared by the liver, thus suggesting a carbohydrate-moiety mediated mechanism. The parenchymal cells of the liver, hepatocytes, are known to abundantly express functional carbohydrate-specific receptors and in this study we therefore used primary rat hepatocytes to study binding and intracellular fate of rFVIIa at a cellular level. Immunofluorescence microscopy showed that rFVIIa was distributed into distinct intracellular vesicles and electron microscopic autoradiography revealed that radioiodinated rFVIIa distributed only into cytoplasmic free vesicles resembling endosomes and lysosomes. These findings suggest that endocytosis of rFVIIa in hepatocytes could be partly mediated via initial membrane binding to a receptor. Quantitative binding studies showed that the presence of excess unlabelled asialo-orosomucoid, asialo-rFVIIa and GalNAc significantly decreased binding of 125I-rFVIIa. An antibody which specifically binds to the carbohydrate recognition domain of the asialoglycoprotein receptor (ASGPR) significantly decreased binding of asialo-rFVIIa by ~36% and rFVIIa by ~19%. Together our data showed that a receptor-mediated mechanism involving the ASGPR is able to bind a subpopulation of unsialylated rFVIIa, while a hepatic mechanism for binding and clearing sialylated rFVIIa is still unknown.

  11. Heterologous recombinant protein with decapacitating activity prevents and reverts cryodamage in ram sperm: An emerging biotechnological tool for cryobiology.

    Science.gov (United States)

    Zalazar, L; Ledesma, A; Hozbor, F; Cesari, A

    2016-01-01

    During the last decades fundamental and applied aspects of mammalian ram sperm cryopreservation have been increasingly explored by scientists and biotechnologists. Many works report modifications in the composition of the freezing extenders and explore the beneficial and detrimental effects of seminal plasma or seminal plasma components in cryopreservation. Seminal plasma is known to contain stabilizing proteins, thereby this is a good start point to study the maintenance of membrane stability based on the basic knowledge of sperm physiology. However, seminal plasma composition is variable among rams and also the introduction of exogenous seminal plasma or its fractions to commercial semen can be associated with the transmission of viral diseases. Our work shows that a mouse protein, called SPINK3 (Serine Protease Inhibitor Kazal type 3) with decapacitating activity interacts with heterologous ram sperm when it is produced as a recombinant molecule. By immunocytochemistry assays we demonstrate that this protein (naturally expressed by mouse seminal vesicle under androgenic control) binds to the apical portion of both fresh and frozen ram sperm, the same localization described in mouse homologous sperm. Furthermore, it significantly improves sperm progressive motility compared to non-treated samples when it is added to freezing extenders and to dilution media after thawing. On the contrary, addition of SPINK3 does not modify sperm viability. The percentage of sperm with intact acrosome after ionophore induction was also significantly higher in sperm frozen in the presence of SPINK3 compared to control samples and the addition of SPINK3 after thawing significantly reduced both induced and non induced acrosomal loss, indicating that heterologous SPINK3 might act as a calcium inhibitor transport as described in mouse. Based on our results SPINK3 may find a place as a desirable biotechnological tool to achieve a higher proportion of competent sperm to fertilize.

  12. Hyperacute thrombolysis with recombinant tissue plasminogen activator of acute ischemic stroke: Feasibility and effectivity from an Indian perspective

    Directory of Open Access Journals (Sweden)

    Sharma S

    2008-01-01

    Full Text Available Given the constraints of resources, thrombolysis for acute ischemic stroke (AIS is under evaluation in developing countries like India, especially in areas such as western Utter Pradesh, where it is overly crowded and there is poor affordability. Aim: This study was done to evaluate recombinant tissue plasminogen activator r-tpa in acute ischemic stroke in hyper acute phase, in selected patients of western Utter Pradesh, in terms of feasibility and effectivity. Design: Open, non randomized study. Materials and Methods: Thirty two patients were classified using Trial of ORG 10172 in Acute Stroke treatment (TOAST criteria (large artery atherosclerotic = 8; cardio embolic = 6; small vessel occlusion = 14; other determined etiology = 2; undetermined etiology = 2. The mean time to reach the hospital was 2 h (1.15-3.0, the mean door to CT scan 20 min (10-40 and door to r-tpa injection was 30 min (24-68. The National Institute of Health Stroke Scale (NIHSS scores ranged from 11-22 (mean 15.5 +2.7. The dose of r-tpa administered was 0.9 mg/kg. Results: Twenty one patients (65.6% showed significant improvement on the NIHSS score, at 48 h (4 points. (Mean change = 10; range = 4-17. At one month, 25 (78% recorded improvement on the Barthel index (mean change = 45%. One developed frontal lobe hemorrhage and another developed recurrent stroke; one died of aspiration; and four showed no improvement. Modified Rankin score (m RS was administered at the end of three months to 28 patients (90%; however, the rest could not be directly observed. The average modified Rankin Score was 1.2 (0-2. Conclusions: Hyperacute thrombolysis was found feasible and effective in selected patients with AIS from western Utter Pradesh and who had poor affordability.

  13. Tousled kinase activator, gallic acid, promotes homologous recombinational repair and suppresses radiation cytotoxicity in salivary gland cells.

    Science.gov (United States)

    Timiri Shanmugam, Prakash Srinivasan; Nair, Renjith Parameshwaran; De Benedetti, Arrigo; Caldito, Gloria; Abreo, Fleurette; Sunavala-Dossabhoy, Gulshan

    2016-04-01

    Accidental or medical radiation exposure of the salivary glands can gravely impact oral health. Previous studies have shown the importance of Tousled-like kinase 1 (TLK1) and its alternate start variant TLK1B in cell survival against genotoxic stresses. Through a high-throughput library screening of natural compounds, the phenolic phytochemical, gallic acid (GA), was identified as a modulator of TLK1/1B. This small molecule possesses anti-oxidant and free radical scavenging properties, but in this study, we report that in vitro it promotes survival of human salivary acinar cells, NS-SV-AC, through repair of ionizing radiation damage. Irradiated cells treated with GA show improved clonogenic survival compared to untreated controls. And, analyses of DNA repair kinetics by alkaline single-cell gel electrophoresis and γ-H2AX foci immunofluorescence indicate rapid resolution of DNA breaks in drug-treated cells. Study of DR-GFP transgene repair indicates GA facilitates homologous recombinational repair to establish a functional GFP gene. In contrast, inactivation of TLK1 or its shRNA knockdown suppressed resolution of radiation-induced DNA tails in NS-SV-AC, and homology directed repair in DR-GFP cells. Consistent with our results in culture, animals treated with GA after exposure to fractionated radiation showed better preservation of salivary function compared to saline-treated animals. Our results suggest that GA-mediated transient modulation of TLK1 activity promotes DNA repair and suppresses radiation cytoxicity in salivary gland cells.

  14. Heterologous recombinant protein with decapacitating activity prevents and reverts cryodamage in ram sperm: An emerging biotechnological tool for cryobiology.

    Science.gov (United States)

    Zalazar, L; Ledesma, A; Hozbor, F; Cesari, A

    2016-01-01

    During the last decades fundamental and applied aspects of mammalian ram sperm cryopreservation have been increasingly explored by scientists and biotechnologists. Many works report modifications in the composition of the freezing extenders and explore the beneficial and detrimental effects of seminal plasma or seminal plasma components in cryopreservation. Seminal plasma is known to contain stabilizing proteins, thereby this is a good start point to study the maintenance of membrane stability based on the basic knowledge of sperm physiology. However, seminal plasma composition is variable among rams and also the introduction of exogenous seminal plasma or its fractions to commercial semen can be associated with the transmission of viral diseases. Our work shows that a mouse protein, called SPINK3 (Serine Protease Inhibitor Kazal type 3) with decapacitating activity interacts with heterologous ram sperm when it is produced as a recombinant molecule. By immunocytochemistry assays we demonstrate that this protein (naturally expressed by mouse seminal vesicle under androgenic control) binds to the apical portion of both fresh and frozen ram sperm, the same localization described in mouse homologous sperm. Furthermore, it significantly improves sperm progressive motility compared to non-treated samples when it is added to freezing extenders and to dilution media after thawing. On the contrary, addition of SPINK3 does not modify sperm viability. The percentage of sperm with intact acrosome after ionophore induction was also significantly higher in sperm frozen in the presence of SPINK3 compared to control samples and the addition of SPINK3 after thawing significantly reduced both induced and non induced acrosomal loss, indicating that heterologous SPINK3 might act as a calcium inhibitor transport as described in mouse. Based on our results SPINK3 may find a place as a desirable biotechnological tool to achieve a higher proportion of competent sperm to fertilize. PMID

  15. Recombinant activated factor VII in the treatment of intractable non-surgical bleeding following major vascular procedures

    Directory of Open Access Journals (Sweden)

    Končar Igor B.

    2008-01-01

    Full Text Available INTRODUCTION A recombinant form of activated factor VII (rFVIIa is a haemostatic drug that is approved for use in haemophiliacs with antibodies to factor VIII or factor IX. Most recent studies and clinical experience have shown that rFVIIa (NovoSeven ®, Novo Nordisk A/S, Denmark gives extreme haemostatic effect in patients with severe "non-haemophilic" bleeding produced after trauma and major surgery. OBJECTIVE We present our preliminary experience of the use of rFVIIa in vascular surgery when conventional haemostatic measures are inadequate. METHOD There were 32 patients divided into five groups: Group I - 14 patients with ruptured abdominal aortic aneurysms; Group II - 10 patients with thoracoabdominal aortic aneurysms; Group III - 5 patients with retroperitoneal tumors involving great abdominal vessels; Group IV - 2 patients with portal hypertension and Group V - one patient with iatrogenic injury of brachial artery and vein during fibrinolytic treatment, because of myocardial infarction. RESULTS Clinical improvement was detected following treatment in 29 patients. Bleeding was successfully controlled as evidenced by improved haemodynamic parameters and decreased inotropic and transfusion requirements. CONCLUSION In vascular patients more liberal use of rFVIIa is limited, because no randomized controlled trial has proved its efficacy and safety in such patients; while also keeping in mind that the price of a 4.8 mg of rFVIIa is $4,080. We recommend the use of rFVIIa in vascular surgery only during and after operative treatment of thoracoabdominal aortic aneurysms, ruptured abdominal aortic aneurysms, retroperitoneal tumors involving the aorta and/or inferior vena cava, as well as portal hypertension, when non-surgical massive uncontrolled bleeding are present.

  16. Influence of soil properties on heavy metal sequestration by biochar amendment: 2. Copper desorption isotherms.

    Science.gov (United States)

    Uchimiya, Minori; Klasson, K Thomas; Wartelle, Lynda H; Lima, Isabel M

    2011-03-01

    Contaminant desorption constrains the long-term effectiveness of remediation technologies, and is strongly influenced by dynamic non-equilibrium states of environmental and biological media. Information is currently lacking in the influence of biochar and activated carbon amendments on desorption of heavy metal contaminants from soil components. In this study, copper sorption-desorption isotherms were obtained for clay-rich, alkaline San Joaquin soil with significant heavy metal sorption capacity, and eroded, acidic Norfolk sandy loam soil having low capacity to retain copper. Acidic pecan shell-derived activated carbon and basic broiler litter biochar were employed in desorption experiments designed to address both leaching by rainfall and toxicity characteristics. For desorption in synthetic rain water, broiler litter biochar amendment diminished sorption-desorption hysteresis. In acetate buffer (pH 4.9), significant copper leaching was observed, unless acidic activated carbon (pH(pzc)=3.07) was present. Trends observed in soluble phosphorus and zinc concentrations for sorption and desorption equilibria suggested acid dissolution of particulate phases that can result in a concurrent release of copper and other sorbed elements. In contrast, sulfur and potassium became depleted as a result of supernatant replacements only when amended carbon (broiler litter biochar) or soil (San Joaquin) contained appreciable amounts. A positive correlation was observed between the equilibrium aluminum concentration and initial copper concentration in soils amended with acidic activated carbon but not basic biochar, suggesting the importance of cation exchange mechanism, while dissolution of aluminum oxides cannot be ruled out. PMID:21190718

  17. The therapeutic effect and prognosis of acute cerebral infarction patients with atrial fibrillation treated by intravenous thrombolysis with recombinant tissue plasminogen activator

    Institute of Scientific and Technical Information of China (English)

    尤寿江

    2013-01-01

    Objective To investigate the efficacy and safety of intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA) in acute cerebral infarct patients with atrial fibrillation (AF) and the predicting factors of poor prognosis.Methods Totally 162 patients with acute cerebral infarct were treated with rt-PA within 4.5hours from the onset.According to past history and the electrocardiogram,the patients was classified into AF

  18. Subretinal recombinant tissue plasminogen activator and pneumatic displacement for the management of subretinal hemorrhage occurring after anti-VEGF injections for wet AMD

    OpenAIRE

    Tognetto, D

    2011-01-01

    Daniele Tognetto, Eirini Skiadaresi, Paolo Cecchini, Giuseppe RavalicoEye Clinic, University of Trieste, Trieste, ItalyAbstract: We describe three cases of submacular hemorrhage that occurred two to four days after anti-VEGF intravitreal injection for occult choroidal neovascularisation in age-related macular degeneration and their management with 25 gauge pars plana vitrectomy with injection of subretinal recombinant tissue plasminogen activator (rTPA) followed by fluid-air exchange and post...

  19. Production of recombinant granulocyte colony-stimulating factor by knocking into the active immunoglobulin heavy chain gene locus in the hybridoma cell line

    OpenAIRE

    Kuwana, Yoshihisa; Funayama, Kikuko; Miyaji, Hiromasa; Hasegawa, Mamoru; Yoshida, Hajime; Itoh, Seiga

    2001-01-01

    The hybridoma cell line KM50 originally produces a monoclonal antibody at a concentration of ∼40 mg ml-1 in ascites. To investigate the possibility to apply this expression system to the production of useful proteins, the cDNA encoding human granulocyte colony-stimulating factor was inserted by homologous recombination into just downstream of the promoter of the active immunoglobulin heavy chain gene of KM50. Site directed integration of targeting DNAs resulted in the disruption of expression...

  20. Cytoplasmic expression of recombinant interleukin-2 and interleukin-4 proteins results in hydrogen peroxide accumulation and reduction in catalase activity in Escherichia coli

    OpenAIRE

    M.S Hejazi; F Karimi; E Mehdizadeh Aghdam; Barzegari, A. (MSc); M Farshdosti Hagh; Parvizi, M.; L Mahmoodi Azar; Hejazi, M. A.

    2009-01-01

    Background and the purpose of the study: The Reactive oxygen species (ROS) is induced in the cells following various stresses but the effect of recombinant protein expression on ROS generation has not been studied yet. In this study, H2O2 concentration and catalase activity variations and their correlation with cell growth following cytoplasmic expression of human interleukin-2 (hIL-2) and mouse interleukin-4 (mIL-4) in Escherichia coli were investigated. Additionally, the effect of recombina...

  1. Influence of Foreign DNA Introduction and Periplasmic Expression of Recombinant Human Interleukin-2 on Hydrogen Peroxide Quantity and Catalase Activity in Escherichia coli

    OpenAIRE

    Lena Mahmoudi Azar; Elnaz Mehdizadeh Aghdam; Farrokh Karimi; Babak Haghshenas; Abolfazl Barzegari; Parichehr Yaghmaei; Mohammad Saeid Hejazi

    2013-01-01

    Purpose: Oxidative stress is generated through imbalance between composing and decomposing of reactive oxygen species (ROS). This kind of stress was rarely discussed in connection with foreign protein production in Escherichia coli. Effect of cytoplasmic recombinant protein expression on Hydrogen peroxide concentration and catalase activity was previously reported. In comparison with cytoplasm, periplasmic space has different oxidative environment. Therefore, in present study we describe t...

  2. High expression of AID and active class switch recombination might account for a more aggressive disease in unmutated CLL patients: link with an activated microenvironment in CLL disease.

    Science.gov (United States)

    Palacios, Florencia; Moreno, Pilar; Morande, Pablo; Abreu, Cecilia; Correa, Agustín; Porro, Valentina; Landoni, Ana Ines; Gabus, Raul; Giordano, Mirta; Dighiero, Guillermo; Pritsch, Otto; Oppezzo, Pablo

    2010-06-01

    Interaction of chronic lymphocytic leukemia (CLL) B cells with tissue microenvironment has been suggested to favor disease progression by promoting malignant B-cell growth. Previous work has shown expression in peripheral blood (PB) of CLL B cells of activation-induced cytidine deaminase (AID) among CLL patients with an unmutated (UM) profile of immunoglobulin genes and with ongoing class switch recombination (CSR) process. Because AID expression results from interaction with activated tissue microenvironment, we speculated whether the small subset with ongoing CSR is responsible for high levels of AID expression and could be derived from this particular microenvironment. In this work, we quantified AID expression and ongoing CSR in PB of 50 CLL patients and characterized the expression of different molecules related to microenvironment interaction. Our results show that among UM patients (1) high AID expression is restricted to the subpopulation of tumoral cells ongoing CSR; (2) this small subset expresses high levels of proliferation, antiapoptotic and progression markers (Ki-67, c-myc, Bcl-2, CD49d, and CCL3/4 chemokines). Overall, this work outlines the importance of a cellular subset in PB of UM CLL patients with a poor clinical outcome, high AID levels, and ongoing CSR, whose presence might be a hallmark of a recent contact with the microenvironment. PMID:20233972

  3. Expression and characterization of recombinant single-chain salmon class I MHC fused with beta2-microglobulin with biological activity

    DEFF Research Database (Denmark)

    Zhao, Heng; Stet, René J M; Skjødt, Karsten;

    2008-01-01

    Heterodimeric class I major histocompatibility complex (MHC) molecules consist of a putative 45-kDa heavy chain and a 12-kDa beta2-microglobulin (beta2m) light chain. The knowledge about MHC genes in Atlantic salmon accumulated during the last decade has allowed us to generate soluble and stable...... antibodies were successfully produced against both the MHC class I heavy chain and beta(2)m, and showed binding to the recombinant molecule. The recombinant complex Sasabeta2mUBA*0301 was expressed and isolated; the production was scaled up by adjusting to its optimal conditions. Subsequently...

  4. Construction and identification of the recombinant adenovirus vector carrying a small interfering RNA targeting the peroxisome proliferator-activated receptor-γ

    Institute of Scientific and Technical Information of China (English)

    LIU Ming; WANG Yi-sheng; LI Yue-bai; ZHAO Guo-qiang

    2012-01-01

    Background Steroid-induced osteonecrosis of the femoral head (ONFH) is a common clinical disease,with a high disability rate.At present,efficient prevention and treatment of steroid-induced ONFH is still lacking.The peroxisome proliferator-activated receptor-γ (PPARγ) is recognized as an important pathogenic gene for the development of steroid-induced ONFH.RNA interference (RNAi) is a tool for functional gene analysis,which has been successfully used to down-regulate the levels of specific target proteins.Therefore,down-regulation of PPARγ expression by RNAi may prevent the incidence of steroid-induced ONFH.Methods According to the principles of siRNA design,three duplex siRNA sequences (971-989,1253-1271 and 1367-1385) derived from the PPARy gene (NM_001082148) were synthesized.These duplexes were annealed,purified and ligated into 1.0-cytomegalovirus (CMV) shuttle vector.The shuttle vector was transfected into HEK293 cells.The HEK293 generated recombinant adenovirus vector carrying PPARγ siRNA sequences was purified and the titer of recombinant adenovirus was determined.Results After the annealing of single-strand DNA oligo encoding short hairpin RNA (shRNA) sequences,products were identified by gel electrophoresis.These products were ligated into the 1.0-CMV shuttle vector and the recombinant shuttle vectors 1.0-CMV-971,1.0-CMV-1253 and 1.0-CMV-1367 were constructed.These sequences of these recombinant vectors were confirmed.We then successfully constructed the recombinant adenovirus vector carrying siRNA targeting PPARγ.After purification,the virus titer was higher than 1010 plaque forming unit (PFU)/ml.Conclusion In this study,three recombinant adenovirus shuttle vectors carrying siRNA targeting PPARγ,including shuttle vectors 1.0-CMV-971,1.0-CMV-1253 and 1.0-CMV-1367,were successfully constructed and high titers of recombinant adenovirus were obtained.

  5. Cloning and expression analysis of recombination activating genes (RAG1/2) in red snapper (Lutjanus sanguineus).

    Science.gov (United States)

    Zhang, X L; Lu, Y S; Jian, J C; Wu, Z H

    2012-04-01

    Recombination activating genes (RAG1 and RAG2), involved in the V(D)J recombination of immunoglobulin and T-cell receptor genes play a crucial role in the adaptive immune response in vertebrates. The expression of these genes was required for the proper development and maturity of lymphocytes so that they can be used as useful markers to evaluate the development of lymphoid organ. In this paper, the cDNA of RAG1 and RAG2 in red snapper, Lutjanus sanguineus were cloned by homological cloning and rapid amplification of cDNA ends (RACE) methods. Results showed the full length of RAG1 cDNA was 3944 bp, containing a 5' untranslated region (UTR) of 200 bp, a 3'-UTR of 561 bp and an open reading frame of 3183 bp encoding 1060 amino acids. Three important structural motifs, a RING/U-box domain, a RING/FYVE/PHD-type domain and a RAG Nonamer-binding domain were detected in the deduced amino acid sequence of RAG1 by InterProScan analysis. The full length of RAG2 cDNA was 2200 bp, consisting of a 141 bp 5'-UTR, a 457 bp 3'-UTR and an open reading frame of 1602 bp encoding 533 amino acids. Two important structural motifs, a Galactose oxidase/kelch, beta-propeller domain and a kelch-type beta-propeller domain were detected in the deduced amino acid sequence of RAG2 by InterProScan analysis. BLAST analysis revealed that the RAG1 and RAG2 in red snapper shared a high homology with other known RAG1 and RAG2 genes, while the greatest degree of identity was observed with Hippoglossus hippoglossus RAG1 at 82% and Takifugu rubripes RAG2 at 87%, respectively. The differential expressions of RAG1 and RAG2 in various tissues of red snapper were analyzed by fluorescent quantitative real-time PCR. The overall expression pattern of the two genes was quite similar. In healthy red snappers, the RAGs transcripts were mainly detected in thymus, following head kidney, spleen, intestine, liver and brain. After vaccinated with inactivated Vibrio alginolyticus 48 h later, the RAGs m

  6. Influence of Foreign DNA Introduction and Periplasmic Expression of Recombinant Human Interleukin-2 on Hydrogen Peroxide Quantity and Catalase Activity in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Lena Mahmoudi Azar

    2013-08-01

    Full Text Available Purpose: Oxidative stress is generated through imbalance between composing and decomposing of reactive oxygen species (ROS. This kind of stress was rarely discussed in connection with foreign protein production in Escherichia coli. Effect of cytoplasmic recombinant protein expression on Hydrogen peroxide concentration and catalase activity was previously reported. In comparison with cytoplasm, periplasmic space has different oxidative environment. Therefore, in present study we describe the effect of periplasmic expression of recombinant human interleukin-2 (hIL-2 on H2O2 concentration and catalase activity in Escherichia coli and their correlation with cell growth. Methods: Having constructed pET2hIL2 vector, periplasmic expression of hIL-2 was confirmed. Then, H2O2 concentration and catalase activity were determined at various ODs. Wild type and empty vector transformed cells were used as negative controls. Results: It was shown that H2O2 concentration in hIL-2 expressing cells was significantly higher than its concentration in wild type and empty vector transformed cells. Catalase activity and growth rate reduced significantly in hIL-2 expressing cells compared to empty vector transformed and wild type cells. Variation of H2O2 concentration and catalase activity is intensive in periplasmic hIL-2 expressing cells than empty vector containing cells. Correlation between H2O2 concentration elevation and catalase activity reduction with cell growth depletion are also demonstrated. Conclusion: Periplasmic expression of recombinant hIL-2 elevates the host cell’s hydrogen peroxide concentration possibly due to reduced catalase activity which has consequent suppressive effect on growth rate.

  7. Superior hydrogen absorption and desorption behavior of Mg thin films

    Science.gov (United States)

    Qu, Jianglan; Wang, Yuntao; Xie, Lei; Zheng, Jie; Liu, Yang; Li, Xingguo

    Pd-capped Mg films prepared by magnetron sputtering achieved complete dehydrogenation in air at room temperature and behaved as favorable gasochromic switchable mirrors. Their cyclic hydrogen absorption and desorption kinetics in air were investigated by using the Bruggeman effective medium approximation. The overall activation energy was 80 kJ mol -1, while the reaction orders controlling desorption were deduced to be n = 2 at 328 K and n = 1 at lower temperatures by analyzing the transmittance data. The hydrogen diffusion coefficient and the corresponding activation energy were calculated by electrochemical measurements. Mg thin films exhibited the smaller activation energy and remarkable diffusion kinetics at room temperature which implied potential applications in smart windows.

  8. Identification of a recombinant inulin fructotransferase (difructose dianhydride III forming) from Arthrobacter sp. 161MFSha2.1 with high specific activity and remarkable thermostability.

    Science.gov (United States)

    Wang, Xiao; Yu, Shuhuai; Zhang, Tao; Jiang, Bo; Mu, Wanmeng

    2015-04-01

    Difructose dianhydride III (DFA III) is a functional carbohydrate produced from inulin by inulin fructotransferase (IFTase, EC 4.2.2.18). In this work, an IFTase gene from Arthrobacter sp. 161MFSha2.1 was cloned and expressed in Escherachia coli. The recombinant enzyme was purified by metal affinity chromatography. It showed significant inulin hydrolysis activity, and the produced main product from inulin was determined as DFA III by nuclear magnetic resonance analysis. The molecular mass of the purified protein was calculated to be 43 and 125 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration, respectively, suggesting the native enzyme might be a homotrimer. The recombinant enzyme showed maximal activity as 2391 units/mg at pH 6.5 and 55 °C. It displayed the highest thermostability among previously reported IFTases (DFA III forming) and was stable up to 80 °C for 4 h of incubation. The smallest substrate was determined as nystose. The conversion ratio of inulin to DFA III reached 81% when 100 g/L inulin was catalyzed by 80 nM recombinant enzyme for 20 min at pH 6.5 and 55 °C. All of these data indicated that the IFTase (DFA III forming) from Arthrobacter sp. 161MFSha2.1 had great potential for industrial DFA III production.

  9. Activity increase in EpoR and Epo expression by intranasal recombinant human erythropoietin (rhEpo) administration in ischemic hippocampi of adult rats.

    Science.gov (United States)

    Castañeda-Arellano, R; Feria-Velasco, A I; Rivera-Cervantes, M C

    2014-11-01

    Erythropoietin in the nervous system is a potential neuroprotective factor for cerebral ischemic damage due to specific-binding to the erythropoietin receptor, which is associated with survival mechanisms. However, the role of its receptor is unclear. Thus, this work assessed whether a low dose (500UI/Kg) of intranasal recombinant human erythropoietin administered 3h after ischemia induced changes in the activation of its receptor at the Tyr456-phosphorylated site in ischemic hippocampi in rats. The results showed that recombinant human erythropoietin after injury maintained cell survival and was associated with an increase in receptor phosphorylation at the Tyr456 site as an initial signaling step, which correlated with a neuroprotective effect. PMID:25219375

  10. Thermal desorption of ammonia from crystalline forsterite surfaces

    OpenAIRE

    Suhasaria, T.; Thrower, J. D.; Zacharias, H.

    2015-01-01

    The thermal desorption of ammonia (NH$_3$) from single crystal forsterite (010) has been investigated using temperature-programmed desorption. The effect of defects on the desorption process has been probed by the use of a rough cut forsterite surface prepared from the cleaved forsterite sample. Several approaches have been used to extract the desorption energy and pre-exponential factor describing the desorption kinetics. In the sub-monolayer coverage regime, the NH$_3$ desorption shows a br...

  11. Desorption and sublimation kinetics for fluorinated aluminum nitride surfaces

    Energy Technology Data Exchange (ETDEWEB)

    King, Sean W., E-mail: sean.king@intel.com; Davis, Robert F. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Nemanich, Robert J. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2014-09-01

    The adsorption and desorption of halogen and other gaseous species from surfaces is a key fundamental process for both wet chemical and dry plasma etch and clean processes utilized in nanoelectronic fabrication processes. Therefore, to increase the fundamental understanding of these processes with regard to aluminum nitride (AlN) surfaces, temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy (XPS) have been utilized to investigate the desorption kinetics of water (H{sub 2}O), fluorine (F{sub 2}), hydrogen (H{sub 2}), hydrogen fluoride (HF), and other related species from aluminum nitride thin film surfaces treated with an aqueous solution of buffered hydrogen fluoride (BHF) diluted in methanol (CH{sub 3}OH). Pre-TPD XPS measurements of the CH{sub 3}OH:BHF treated AlN surfaces showed the presence of a variety of Al-F, N-F, Al-O, Al-OH, C-H, and C-O surfaces species in addition to Al-N bonding from the AlN thin film. The primary species observed desorbing from these same surfaces during TPD measurements included H{sub 2}, H{sub 2}O, HF, F{sub 2}, and CH{sub 3}OH with some evidence for nitrogen (N{sub 2}) and ammonia (NH{sub 3}) desorption as well. For H{sub 2}O, two desorption peaks with second order kinetics were observed at 195 and 460 °C with activation energies (E{sub d}) of 51 ± 3 and 87 ± 5 kJ/mol, respectively. Desorption of HF similarly exhibited second order kinetics with a peak temperature of 475 °C and E{sub d} of 110 ± 5 kJ/mol. The TPD spectra for F{sub 2} exhibited two peaks at 485 and 585 °C with second order kinetics and E{sub d} of 62 ± 3 and 270 ± 10 kJ/mol, respectively. These values are in excellent agreement with previous E{sub d} measurements for desorption of H{sub 2}O from SiO{sub 2} and AlF{sub x} from AlN surfaces, respectively. The F{sub 2} desorption is therefore attributed to fragmentation of AlF{sub x} species in the mass spectrometer ionizer. H{sub 2} desorption exhibited

  12. Attenuated recombinant vaccinia virus expressing oncofetal antigen (tumor-associated antigen) 5T4 induces active therapy of established tumors.

    Science.gov (United States)

    Mulryan, Kate; Ryan, Matthew G; Myers, Kevin A; Shaw, David; Wang, Who; Kingsman, Susan M; Stern, Peter L; Carroll, Miles W

    2002-10-01

    The human oncofetal antigen 5T4 (h5T4) is a transmembrane glycoprotein overexpressed by a wide spectrum of cancers, including colorectal, ovarian, and gastric, but with a limited normal tissue expression. Such properties make 5T4 an excellent putative target for cancer immunotherapy. The murine homologue of 5T4 (m5T4) has been cloned and characterized, which allows for the evaluation of immune intervention strategies in "self-antigen" in vivo tumor models. We have constructed recombinant vaccinia viruses based on the highly attenuated and modified vaccinia virus ankara (MVA strain), expressing h5T4 (MVA-h5T4), m5T4 (MVA-m5T4), and Escherichia coli LacZ (MVA-LacZ). Immunization of BALB/c and C57BL/6 mice with MVA-h5T4 and MVA-m5T4 constructs induced antibody responses to human and mouse 5T4, respectively. C57BL/6 and BALB/c mice vaccinated with MVA-h5T4 were challenged with syngeneic tumor line transfectants, B16 melanoma, and CT26 colorectal cells that express h5T4. MVA-h5T4-vaccinated mice showed significant tumor retardation compared with mice vaccinated with MVA-LacZ or PBS. In active treatment studies, inoculation with MVA-h5T4 was able to treat established CT26-h5T4 lung tumor and to a lesser extent B16.h5T4 s.c. tumors. Additionally, when C57BL/6 mice vaccinated with MVA-m5T4 were challenged with B16 cells expressing m5T4, resulting growth of the tumors was significantly retarded compared with control animals. Furthermore, mice vaccinated with MVA-m5T4 showed no signs of autoimmune toxicity. These data support the use of MVA-5T4 for tumor immunotherapy. PMID:12481437

  13. Intravenous thrombolysis with recombinant tissue plasminogen activator for ischemic stroke patients over 80 years old: the Fukuoka Stroke Registry.

    Directory of Open Access Journals (Sweden)

    Ryu Matsuo

    Full Text Available The benefit of intravenous recombinant tissue plasminogen activator (rt-PA therapy for very old patients with acute ischemic stroke remains unclear. The aim of this study was to elucidate the efficacy and safety of intravenous rt-PA therapy for patients over 80 years old.Of 13,521 stroke patients registered in the Fukuoka Stroke Registry in Japan from June 1999 to February 2013, 953 ischemic stroke patients who were over 80 years old, hospitalized within 3 h of onset, and not treated with endovascular therapy were included in this study. Among them, 153 patients were treated with intravenous rt-PA (0.6 mg/kg. For propensity score (PS-matched case-control analysis, 148 patients treated with rt-PA and 148 PS-matched patients without rt-PA therapy were selected by 1:1 matching with propensity for using rt-PA. Clinical outcomes were neurological improvement, good functional outcome at discharge, in-hospital mortality, and hemorrhagic complications (any intracranial hemorrhage [ICH], symptomatic ICH, and gastrointestinal bleeding.In the full cohort of 953 patients, rt-PA use was associated positively with neurological improvement and good functional outcome, and negatively with in-hospital mortality after adjustment for multiple confounding factors. In PS-matched case-control analysis, patients treated with rt-PA were still at lower risk for unfavorable clinical outcomes than non-treated patients (neurological improvement, odds ratio 2.67, 95% confidence interval 1.61-4.40; good functional outcome, odds ratio 2.23, 95% confidence interval 1.16-4.29; in-hospital mortality, odds ratio 0.30, 95% confidence interval 0.13-0.65. There was no significant association between rt-PA use and risk of hemorrhagic complications in the full and PS-matched cohorts.Intravenous rt-PA therapy was associated with improved clinical outcomes without significant increase in risk of hemorrhagic complications in very old patients (aged>80 years with acute ischemic stroke.

  14. Use of activated recombinant factor VII for severe coagulopathy post ventricular assist device or orthotopic heart transplant

    Directory of Open Access Journals (Sweden)

    Despotis George J

    2007-07-01

    Full Text Available Abstract Background Ventricular assist devices(VAD implantation/removal is a complex surgical procedure with perioperative bleeding complications occurring in nearly half of the cases. Recombinant activated factor VII (rFVIIa has been used off-label to control severe hemorrhage in surgery and trauma. We report here our experience with rFVIIa as a rescue therapy to achieve hemostasis in patients undergoing orthotopic heart transplant (OHT and/or VAD implantation. Methods A retrospective review was conducted from Jan 03 to Aug 05 for patients who received rFVIIa for the management of intractable bleeding unresponsive to standard hemostatic blood component therapy. Blood loss and the quantity of blood products, prior to, and for at least 12 hours after, administration of rFVIIa were recorded. Results Mean patient age was 53, (38–64 yrs, mean dose of rFVIIa administered was 78.3 μg/kg (24–189 μg/kg in 1–3 doses. All patients received the drug either intraoperatively or within 6 hours of arrival in ICU. Mean transfusion requirements and blood loss were significantly reduced after rFVIIa administration (PRBC's; 16.9 ± 13.3 to 7.1 ± 6.9 units, FFP; 13.1 ± 8.2 to 4.1 ± 4.9 units, platelets; 4.0 ± 2.8 to 2.1 ± 2.2 units, p Conclusion In this review, there was a significant decrease in transfusion requirement and blood loss after rFVIIa administration. Although, 5/17 developed thromboembolic complications, these patients may have been at higher risk based on the multiple modality therapy used to manage intractable bleeding. Nevertheless, the exact role of rFVIIa with respect to development of thromboembolic complications cannot be clearly determined. Further investigation is needed to determine rFVIIa's safety and its effectiveness in improving postoperative morbidity and mortality.

  15. Cytoplasmic expression of recombinant interleukin-2 and interleukin-4 proteins results in hydrogen peroxide accumulation and reduction in catalase activity in Escherichia coli

    Directory of Open Access Journals (Sweden)

    M.S Hejazi

    2009-08-01

    Full Text Available Background and the purpose of the study: The Reactive oxygen species (ROS is induced in the cells following various stresses but the effect of recombinant protein expression on ROS generation has not been studied yet. In this study, H2O2 concentration and catalase activity variations and their correlation with cell growth following cytoplasmic expression of human interleukin-2 (hIL-2 and mouse interleukin-4 (mIL-4 in Escherichia coli were investigated. Additionally, the effect of recombinant protein expression under different conditions was compared to the effect of foreign DNA introduction on these factors. Methods: Plasmids pEThIL-2 and pETmIL-4 were used for expression of human interleukin-2 (hIL-2 and mouse interleukin-4 (mIL-4 inside the cytoplasm of the cells. Having confirmed protein expression using SDS-PAGE analysis and ELISA assay, H2O2 concentration and catalase activity were measured at various ODs. Results and major conclusion: Empty vector introduction increased significantly H2O2 concentration of the cells. However, H2O2 concentration in hIL-2 and mIL-4 expressing cells was significantly higher than its concentration in empty vector transformed cells. Catalase activity was reduced in foreign DNA introduced cells. It was more lowered following expression of recombinant proteins. Results of this study revealed the relationship between foreign DNA introduction and protein expression with H2O2 elevation and catalase activity reduction. There was also correlation between H2O2 elevation and reduction in catalase activity with the cell growth depression.

  16. Preparation and Absorption/Desorption Performance of Gypsum-based Humidity Controlling Materials

    Institute of Scientific and Technical Information of China (English)

    JIANG Hongyi; LUAN Congmei

    2011-01-01

    Absorption/desorption properties of some humidity controlling materials which contain gypsum as basic cement materials and activated Sepiolite powder as humidity controlling media were tested.The kinetics curve of moisture adsorption/desorption were drawn and humidity controlling performance in nature environment was verified.The experimental results show that moisture absorption/desorption rates are increased,and the speed is also accelerated.These materials,which can adjust environmental humidity effectively,are new ones with good humidity controlling performance.

  17. Thermal desorption of oxygen from near-stoichiometric cationic vanadium oxide clusters

    Science.gov (United States)

    Kurokawa, Hodaka; Mafuné, Fumitaka

    2016-05-01

    Oxygen desorption from cationic vanadium oxide clusters, VnOm+ (n = 2-10), composed of a near-stoichiometric (n:m = 2:5) frame with excess oxygen attached was investigated in a thermal energy region by time-of-flight mass spectrometry and thermal desorption spectrometry. Oxygen molecules were observed to desorb from the clusters during heating. The activation energy for desorption was estimated from the temperature dependence of different clusters and exhibited an even-odd alternation with respect to the cluster size, n. This alternation can be explained in terms of oxidation states of the vanadium atoms.

  18. High-level expression of a novel recombinant human plasminogen activator (rhPA) in the milk of transgenic rabbits and its thrombolytic bioactivity in vitro.

    Science.gov (United States)

    Song, Shaozheng; Ge, Xin; Cheng, Yaobin; Lu, Rui; Zhang, Ting; Yu, Baoli; Ji, Xueqiao; Qi, Zhengqiang; Rong, Yao; Yuan, Yuguo; Cheng, Yong

    2016-08-01

    The human tissue-type plasminogen activator (tPA) is a key kinase of fibrinolysis that plays an important role in dissolving fibrin clots to promote thrombolysis. The recombinant human plasminogen activator (rhPA) has more thrombolytic advantages than the wild type tPA. To increase the half-life and thrombolytic activity of tPA, a mutant containing only the essential K2 fibrin-binding and P activating plasminogen domains of the wild type tPA was cloned. This fragment was then inserted into goat β-casein regulatory sequences. Then, a mammary gland-specific expression vector, PCL25/rhPA, was constructed, and the transgenic rabbits were generated. In this study, 18 live transgenic founders (12♀, 6♂) were generated using pronuclear microinjection. Six transgenic rabbits were obtained, and the expression levels of rhPA in the milk had a range of 15.2-630 µg/ml. A fibrin agarose plate assay of rhPA showed that it had strong thrombolytic bioactivity in vitro, and the highest specific activity was >360 (360 times more than that of alteplase). The results indicated that the rhPA containing only the K2 and P domains is efficiently expressed with higher thrombolytic bioactivity in the milk of transgenic rabbits. Our study also demonstrated a new method for the large-scale production of clinically relevant recombinant pharmaceutical proteins in the mammary glands of transgenic rabbits. PMID:27230577

  19. Contribution of generation-recombination processes at inner interface of MBE-grown Hg1-xCdxTe heterostucture to dark current of small active area photodiode

    Science.gov (United States)

    Chekanova, Galina V.; Drugova, Albina A.; Kholodnov, Viacheslav; Nikitin, Mikhail S.

    2009-09-01

    Multilayer heterostructures of Hg1-xCdxTe alloy grown by Molecular Beam Epitaxy (MBE) on large size alternative substrates Si, GaAs and Ge are considered as one of productive alternative materials for issue of large format photovoltaic (PV) infrared (IR) focal plane arrays. However reaching of ultimate performance of small-pitched photodiode's (PD) covering spectral range from 8 to 12 μm depends on electronic properties of both individual layers and heterostructure interfaces. Due to small thickness of heterostructure layers, interfaces are located close to active regions of p-n junction and hence generation-recombination processes at interfaces will contribute to value of current flowing through junction. As usual measured dark current value of small-sized PD is higher than estimated from calculation and cannot be explained by discrepancy between real and estimated charge carriers concentration in absorption layers where p-n junction is formed. Objective of the present work was to calculate the contribution of recombination of charge carriers via electronic states on nearby inner interface to dark current of Hg1-xCdxTe LWIR PD (λco equals to 9.5-10.3 μm at Top=77 K) and its variation with absorption layer parameters and compare it to measured data on small-pitched arrays. We have concluded previously that at high recombination rate dark current can grow in orders of value.

  20. Equilibrium adsorption data from temperature-programmed desorption experiments

    OpenAIRE

    Foeth, Frank; Mugge, José; Vaart, van der, A.W.; Bosch, Hans; Reith, Tom

    1996-01-01

    This work describes a novel method that enables the calculation of a series of adsorption isotherms basically from a single Temperature-Programmed Desorption (TPD) experiment. The basic idea is to saturate an adsorbent packed in a fixed bed at a certain feed concentration and temperature and to subsequently increase its temperature linearly with time, while maintaining a constant feed concentration. We measured TPD response curves for carbon dioxide on activated carbon at different heating ra...

  1. Discovery of the recombining plasma in the south of the Galactic center; a relic of the past Galactic center activity?

    CERN Document Server

    Nakashima, S; Uchida, H; Tanaka, T; Tsuru, T G; Koyama, K; Murakami, H; Uchiyama, H

    2013-01-01

    We report Suzaku results for soft X-ray emission to the south of the Galactic center (GC). The emission (hereafter "GC South") has an angular size of ~42' x 16' centered at (l, b) ~ (0.0, -1.4), and is located in the largely extended Galactic ridge X-ray emission (GRXE). The X-ray spectrum of GC South exhibits emission lines from highly ionized atoms. Although the X-ray spectrum of the GRXE can be well fitted with a plasma in collisional ionization equilibrium (CIE), that of GC South cannot be fitted with a plasma in CIE, leaving hump-like residuals at ~2.5 and 3.5 keV, which are attributable to the radiative recombination continua of the K-shells of Si and S, respectively. In fact, GC South spectrum is well fitted with a recombination-dominant plasma model; the electron temperature is 0.46 keV while atoms are highly ionized (kT = 1.6 keV) in the initial epoch, and the plasma is now in a recombining phase at a relaxation scale (plasma density x elapsed time) of 5.3 x 10^11 s cm^-3. The absorption column densi...

  2. Tilapia follicle-stimulating hormone (FSH): immunochemistry, stimulation by gonadotropin-releasing hormone, and effect of biologically active recombinant FSH on steroid secretion.

    Science.gov (United States)

    Aizen, Joseph; Kasuto, Harel; Golan, Matan; Zakay, Hila; Levavi-Sivan, Berta

    2007-04-01

    In fish, FSH is generally important for early gonadal development and vitellogenesis. As in mammals, FSH is a heterodimer composed of an alpha subunit that is noncovalently associated with the hormone-specific beta subunit. The objective of the present study was to express glycosylated, properly folded, and biologically active tilapia FSH (tFSH) using the Pichia pastoris expression system. Using this material, we aimed to develop a specific ELISA and to enable the study of FSH response to GnRH. The methylotrophic yeast P. pastoris was used to coexpress recombinant genes formed by fusion of mating factor alpha leader and tilapia fshb and cga coding sequences. Western blot analysis of tilapia pituitary FSH, resolved by SDS-PAGE, yielded a band of 15 kDa, while recombinant tFSH beta (rtFSH beta) and rtFSH beta alpha had molecular masses of 17-18 kDa and 26-30 kDa, respectively. Recombinant tFSH beta alpha was found to bear only N-linked carbohydrates. Recombinant tFSH beta alpha significantly enhanced 11-ketotestosterone (11-KT) and estradiol secretion from tilapia testes and ovaries, respectively, in a dose-dependent manner (similar to tilapia pituitary extract, affinity-purified pituitary FSH, and porcine FSH). Using antibodies raised against rtFSH beta, FSH-containing cells were localized adjacent to hypothalamic nerve fibers ramifying in the proximal pars distalis (PPD), while LH cells were localized in a more peripheral region of the PPD. Moreover, FSH is under the control of hypothalamic decapeptide GnRH, an effect that was abolished through the use of specific bioneutralizing antisera, anti-rtFSH beta. It also reduced basal secretion of 11-KT. PMID:17192515

  3. 活性碳纤维吸附水中酚及脱附条件实验研究%An Experimental Study on Phenols Compounds Adsorption-desorption by Activated Carbon Fibers

    Institute of Scientific and Technical Information of China (English)

    董茹

    2012-01-01

    化工、医药等行业排出的含酚废水对环境造成的污染十分严重,其废水的处理日益受到重视.活性炭纤维(Activated Carbon Fibers,ACF)作为一种新型吸附材料,其具有的大比表面积、丰富微孔结构等特点,使其吸附过程效率高.并且其吸附操作设备具有简单、方便、能耗低等优点,从而使该吸附法成为近年来一种快速发展的废水处理方法.本研究通过静态条件下的吸脱附性能研究,研究了ACF吸附水中酚的规律,确定了最佳的吸附时间为4h,水溶液pH为弱酸性及低温有利于吸附的结果,得到了准确的平衡吸附量;找到了合适的ACF脱附再生剂NaOH,并测试出其多次再生的利用率.%The phenols wastewater pollution from chemical and pharmaceutical industry on environment becomes serious. Activated carbon fibers( ACF)as a new kind of fibrous adsorbent has been on exeillent candidate for waste water treatment due to its specific surface area, pore diameter, pore size distribution and cellular structure,and it's adsorption equipment is smiple and low energy consumption. In this study, adsorption-desorption of ACF and regular pattern of phenols were explored under static condition. The results indicate that 4 h adsorption time, faintly acid and low temperture promote the adsorption, and obtaining the exact equilibrium adsorption capacity. NaOH was confirmed to be on efficient desoption regeneration agent.

  4. A new recombinant pituitary adenylate cyclase-activating peptide-derived peptide efficiently promotes glucose uptake and glucose-dependent insulin secretion

    Institute of Scientific and Technical Information of China (English)

    Yi Ma; Tianjie Luo; Wenna Xu; Zulu Ye; An Hong

    2012-01-01

    The recombinant peptide,DBAYL,a promising therapeutic peptide for type 2 diabetes,is a new,potent,and highly selective agonist for VPAC2 generated through sitedirected mutagenesis based on sequence alignments of pituitary adenylate cyclase-activating peptide (PACAP),vasoactive intestinal peptide (VIP),and related analogs.The recombinant DBAYL was used to evaluate its effect and mechanism in blood glucose metabolism and utilization.As much as 28.9 mg recombinant DBAYL peptide with purity over 98% can be obtained from 1 I of Luria-Bertani medium culture by the method established in this study and the prepared DBAYL with four mutations (N10Q,V18L,N29Q,and M added to the N-terminal)were much more stable than BAY55-9837.The half-life of recombinant DBAYL was about 25 folds compared with that of BAY55-9837 in vitro.The bioactivity assay of DBAYL showed that it displaced [125I]PACAP38 and [125I]VIP from VPAC2 with a half-maximal inhibitory concentration of 48.4 ± 6.9 and 47.1 ± 4.9 nM,respectively,which were significantly lower than that of BAY55-9837,one established VPAC2 agonists.DBAYL enhances the cAMP accumulation in CHO cells expressing human VPAC2 with a half-maximal stimulatory concentration (EC5o) of 0.68 nM,whereas the receptor potency of DBAYL at human VPAC1 (ECso of 737 nM) was only 1/1083of that at human VPAC2,and DBAYL had no activity toward human PAC1 receptor.Western blot analysis of the key proteins of insulin receptor signaling pathway:insulin receptor substrate 1 (IRS-1) and glucose transporter 4(GLUT4) indicated that the DBAYL could significantly induce the insulin-stimulated IRS-1 and GLUT4 expression more efficiently than BAY55-9837 and VIP in adipocytes.Compared with BAY55-9837 and PACAP38,the recombinant peptide DBAYL can more efficiently promote insulin release and decrease plasma glucose level in Institute of Cancer Research (ICR) mice.These results suggested that DBAYL could efficiently improve glucose uptake and glucose-dependent insulin

  5. Enhanced hydrogen desorption property of MgH{sub 2} with the addition of cerium fluorides

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Huai-Jun, E-mail: huaijun.lin.489@s.kyushu-u.ac.jp [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Department of Mechanical Engineering, Faculty of Engineering, Kyushu University, Fukuoka 819-0395 (Japan); Matsuda, Junko [International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, Fukuoka 819-0395 (Japan); Li, Hai-Wen [International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, Fukuoka 819-0395 (Japan); International Research Center for Hydrogen Energy, Kyushu University, Fukuoka 819-0395 (Japan); Zhu, Min [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); China–Australia Joint Laboratory for Energy & Environmental Materials, South China University of Technology, Guangzhou 510640 (China); Akiba, Etsuo [Department of Mechanical Engineering, Faculty of Engineering, Kyushu University, Fukuoka 819-0395 (Japan); International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, Fukuoka 819-0395 (Japan); International Research Center for Hydrogen Energy, Kyushu University, Fukuoka 819-0395 (Japan)

    2015-10-05

    Highlights: • Activation energy of MgH{sub 2} desorption is remarkably reduced with the dopant of CeF{sub 4}. • The improvement might be attributed to new Ce–F–Mg species at the CeF{sub 4}/MgH{sub 2} interface. • Easy electron transfer induced from the high valence Ce-cation benefits MgH{sub 2} desorption. - Abstract: Hydrogen desorption property of MgH{sub 2} doped with cerium fluorides with different valences prepared using ball milling has been studied. CeF{sub 4} is catalytically active for hydrogen desorption of MgH{sub 2}. Hydrogen desorption temperature and apparent activation energy of MgH{sub 2} are significantly reduced with dopant of 2 mol% of CeF{sub 4}, which might be attributed to the formation of a new Ce–F–Mg specie at the CeF{sub 4}/MgH{sub 2} interface and the easy electron transfer induced from the high valence Ce-cation. The apparent activation energy of hydrogen desorption of MgH{sub 2} is reduced from ∼160 kJ/mol to ∼110 kJ/mol with the dopant of CeF{sub 4}.

  6. Plasma Desorption Mass Spectrometry: Coming of Age.

    Science.gov (United States)

    Cotter, Robert J.

    1988-01-01

    Discusses the history and development of Plasma Desorption Mass Spectrometry to determine molecular weights and structures of proteins and polymers. Outlines theory, instrumentation, and sample preparation commonly used. Gives several examples of resulting spectra. (ML)

  7. Bentazone adsorption and desorption on agricultural soils

    OpenAIRE

    Boivin, A.; Cherrier, R.; Schiavon, M

    2005-01-01

    Herbicide fate and transport in soils greatly depend upon adsorption-desorption processes. Batch adsorption and desorption experiments were performed with the herbicide bentazone using 13 contrasted agricultural soil samples. Bentazone was found to be weakly sorbed by the different soils, showing average Freundlich adsorption coefficients (Kf) value of 1.4 ± 2.3 mg1 - nf Lnf kg-1. Soil organic matter content did not have a significant effect on bentazone sorption (r2 = 0.12), whereas natural ...

  8. Use of recombinant activated factor VII for reduction of perioperative blood loss during elective surgical correction of spine deformity in a Jehovah's Witness. Case report.

    Science.gov (United States)

    Kącka, Katarzyna; Kącki, Wojciech; Merak, Joanna; Błęka, Adam

    2010-01-01

    Planned surgical procedures at patients who refuse allogenic blood transfusion because of religious convictions are important problem, not only medical but also ethical and juristical. At the study authors report the successful use of activated recombinant factor VII (rFVIIa) for the reduction of perioperative blood loss in four years old child - Jehovah's Witness, who had planned Torode kyphectomy. Applied perioperative management together with preparing to surgery with erythropoietin allowed for reduction of blood loss and avoiding of blood transfusion. Authors state, that appropriate perioperative proceeding makes a possibility of safe surgical procedures also at patients who refuse the transfusion. PMID:21057153

  9. Neutrino-recoil induced desorption

    International Nuclear Information System (INIS)

    Nuclear decay induced 37Cl ion desorption from the electron capture decay 37Ar→37Cl+ν is reported for the first time. A mixture of one part 36Ar and ∼5x10-5 parts 37Ar (36/37Ar) is physisorbed on a gold-plated Si wafer kept at 16 K under ultrahigh vacuum conditions. The time of flight (TOF) of recoiled 37Cl ions is measured using coincidence techniques. The observed kinetic energy distribution of the 37Cl ions is approximately Gaussian in shape, with a maximum at ∼9.0 eV and a full width at half-maximum of ∼3 eV. Considering the binding energy of physisorbed 37Ar is ∼80 meV, the 9-eV peak energy compares well with that of the gas-phase value, where conservation of the energy and momentum fixes the kinetic energy of 37Cl ions at 9.54 eV. Using a combination of TOF and retarding field energy analysis, the charge states of detected ions for 1 ML (monolayer) of 36/37Ar are determined as 53%+1e, 21%+2e, and 26%+ne, where n≥3. The fraction of decaying 37Ar atoms which emerge from the surface as positive 37Cl ions is found to be 10%. Finally, a strong charge exchange reaction between a 37Cl ion and near-neighbor atoms causes a Coulomb explosion within the multilayers, increasing the kinetic energy of desorbing ions by as much as ∼7 eV

  10. Soluble recombinant influenza vaccines.

    OpenAIRE

    Fiers, W; Neirynck, S; Deroo, T; Saelens, X; Jou, W M

    2001-01-01

    Soluble, recombinant forms of influenza A virus haemagglutinin and neuraminidase have been produced in cells of lower eukaryotes, and shown in a mouse model to induce complete protective immunity against a lethal virus challenge. Soluble neuraminidase, produced in a baculovirus system, consisted of tetramers, dimers and monomers. Only the tetramers were enzymatically active. The immunogenicity decreased very considerably in the order tetra > di > mono. Therefore, we fused the head part of the...

  11. Thermal desorption of helium from homogeneously implanted graphite

    Science.gov (United States)

    Jung, P.; Schroeder, H.

    1991-11-01

    Super-fine grain graphite (FGG) and pyrolytic carbon (PYC) of thicknesses around 200 μm were homogeneously implanted at room temperature with α-particles (0.5 MeV ≤ Eα ≤ 22 MeV). Thermal helium desorption spectrometry in the temperature range from 400 to 1900 K can be described by diffusion kinetics with an activation energy of 1.1 eV in FGG and about 0.75 eV in PYC. Desorption during temperature ramping at a constant rate of 0.83 K/s also shows significant differences of the two graphite species. It is found that in FGG and especially in PYC a considerable fraction of the implanted helium is retained even beyond 1000 K. This is in contrast to results reported after low energy implantations to high doses for various graphite species.

  12. Inhibitory Effects of Vegetable Juices on CYP3A4 Activity in Recombinant CYP3A4 and LS180 Cells.

    Science.gov (United States)

    Tsujimoto, Masayuki; Uchida, Tomoe; Kozakai, Hiroyuki; Yamamoto, Saori; Minegaki, Tetsuya; Nishiguchi, Kohshi

    2016-01-01

    It is thought that eating habits induces individual variation in intestinal absorption and metabolism of drugs. The objective of this research was to clarify the influence of vegetables juices on CYP3A4 activity, which is an important enzyme in intestine. Five vegetables juices (VJ-o, Kagome Original(®); VJ-g, Kagome 30 kinds of vegetables and fruits(®); VJ-p, Kagome Purple vegetables(®); VJ-r, Kagome Sweet Tomato(®); and VJ-y, Kagome Fruity Salada(®); KAGOME Co., Ltd., Aichi, Japan) were centrifuged (1630×g, 10 min) and filtered using filter paper and 0.45-µm membrane filters. In this study, recombinant CYP3A4 and LS180 cells were used for the evaluation of CYP3A4 activity. The metabolisms to 6β-hydroxytestosterone by recombinant CYP3A4 were significantly inhibited by VJ-o, VJ-g, and VJ-y in a preincubation time-dependent manner, and CYP3A4 activity in LS180 cells were significantly inhibited by VJ-o and VJ-y. These results show that the difference in ingestion volume of vegetable juices and vegetables might partially induce individual difference in intestinal drug metabolism. PMID:27582329

  13. Inhibitory Effects of Vegetable Juices on CYP3A4 Activity in Recombinant CYP3A4 and LS180 Cells.

    Science.gov (United States)

    Tsujimoto, Masayuki; Uchida, Tomoe; Kozakai, Hiroyuki; Yamamoto, Saori; Minegaki, Tetsuya; Nishiguchi, Kohshi

    2016-01-01

    It is thought that eating habits induces individual variation in intestinal absorption and metabolism of drugs. The objective of this research was to clarify the influence of vegetables juices on CYP3A4 activity, which is an important enzyme in intestine. Five vegetables juices (VJ-o, Kagome Original(®); VJ-g, Kagome 30 kinds of vegetables and fruits(®); VJ-p, Kagome Purple vegetables(®); VJ-r, Kagome Sweet Tomato(®); and VJ-y, Kagome Fruity Salada(®); KAGOME Co., Ltd., Aichi, Japan) were centrifuged (1630×g, 10 min) and filtered using filter paper and 0.45-µm membrane filters. In this study, recombinant CYP3A4 and LS180 cells were used for the evaluation of CYP3A4 activity. The metabolisms to 6β-hydroxytestosterone by recombinant CYP3A4 were significantly inhibited by VJ-o, VJ-g, and VJ-y in a preincubation time-dependent manner, and CYP3A4 activity in LS180 cells were significantly inhibited by VJ-o and VJ-y. These results show that the difference in ingestion volume of vegetable juices and vegetables might partially induce individual difference in intestinal drug metabolism.

  14. Relationship of Impairment of Schistosome 28-Kilodalton Glutathione S-Transferase (GST) Activity to Expression of Immunity to Schistosoma mattheei in Calves Vaccinated with Recombinant Schistosoma bovis 28-Kilodalton GST

    OpenAIRE

    Grzych, Jean-Marie; De Bont, Jan; Liu, Jinli; Neyrinck, Jean-Loup; Fontaine, Josette; Vercruysse, Jozef; Capron, André

    1998-01-01

    Sera from calves vaccinated with the recombinant Schistosoma bovis-derived 28-kDa glutathione S-transferase (28GST) and subsequently naturally or experimentally exposed to Schistosoma mattheei were studied for their content of specific immunoglobulin G (IgG) and IgA antibodies to recombinant S. bovis 28GST as well as for their capacity to inhibit the enzymatic activity of the antigen. The results were analyzed in regard to the presence (natural infection) or absence (experimental infection) o...

  15. Cloning, Expression and Activity of Recombinant Human Angiostatin%重组人血管抑素的克隆、表达及活性测定

    Institute of Scientific and Technical Information of China (English)

    姜颖; 孙陆果; 于永利

    2000-01-01

    目的:研究血管抑素(angiostatin)的临床应用价值,将其开发为多肽类药物。方法:以RT-PCR从胎儿肝脏钓取人血管抑素全编码区cDNA,使用Pichia分泌型酵母表达系统表达重组人血管抑素,重组蛋白经肝素亲和层析纯化后,以鸡胚尿囊膜法血管生成实验及小鼠创伤愈合实验检测活性。结果:重组人血管抑素在酵母系统中得到较高量表达(5 mg/L),经肝素亲和层析纯化,SDS-PAGE显示分子量为43 kD。活性实验表明,重组蛋白能够抑制新生血管形成、抑制伤口愈合。结论:重组人血管抑素在酵母系统中实现高效表达,并具有很好的生物学活性。%Objective: To express recombinant human angiostatin for further application in clinic. Methods: The complete encoding eDNA of human angiostatin was isolated from human embryo liver with RT-PCR and expressed in secretory Pichia expression system. Recombinant human angiostatin was purified with heparin sepharose chromatography and its activity was determined in chick embryo chorioallantoic membrane (CAM) and wound healing assays. Results: Expressed in large quantity (yield=5 mg/L) and purified with heparin sepharose, recombinant angiostatin was showed to have a molecular weight of 43 kD in SDS-PAGE and potently inhibit angiogenesis and wound healing. Conclusion: Recombinant human angiostatin was expressed efficiently in a biologically active form.

  16. Heat-integrated liquid-desorption exchanger (HILDE) for CO2 desorption

    NARCIS (Netherlands)

    Ham, L.V. van der; Khakharia, P.M.; Goetheer, E.L.V.

    2016-01-01

    A novel type of separating heat exchanger, called a heat-integrated liquid-desorption exchanger (HILDE), applied to a typical CO2 desorption process, has been investigated both numerically and experimentally. Process simulations, hydrodynamic and mass transfer experiments, and a preliminary cost eva

  17. New perspectives in vacuum high voltage insulation. II. Gas desorption

    CERN Document Server

    Diamond, W T

    1998-01-01

    An examination has been made of gas desorption from unbaked electrodes of copper, niobium, aluminum, and titanium subjected to high voltage in vacuum. It has been shown that the gas is composed of water vapor, carbon monoxide, and carbon dioxide, the usual components of vacuum outgassing, plus an increased yield of hydrogen and light hydrocarbons. The gas desorption was driven by anode conditioning as the voltage was increased between the electrodes. The gas is often desorbed as microdischarges-pulses of a few to hundreds of microseconds-and less frequently in a more continuous manner without the obvious pulsed structure characteristic of microdischarge activity. The quantity of gas released was equivalent to many monolayers and consisted mostly of neutral molecules with an ionic component of a few percent. A very significant observation was that the gas desorption was more dependent on the total voltage between the electrodes than on the electric field. It was not triggered by field-emitted electrons but oft...

  18. Investigations on the activation of recombinant microbial pro-transglutaminase: in contrast to proteinase K, dispase removes the histidine-tag.

    Science.gov (United States)

    Sommer, Christian; Hertel, Thomas C; Schmelzer, Christian E H; Pietzsch, Markus

    2012-02-01

    In order to produce recombinant microbial transglutaminase (rMTG) which is free of the activating protease, dispase was used to activate the pro-rMTG followed by immobilized metal affinity chromatography (IMAC). As shown by MALDI-MS, the dispase does not only cleave the pro-sequence, but unfortunately also cleaves within the C-terminal histidine-tag. Hence, the active rMTG cannot properly bind to the IMAC material. As an alternative, proteinase K was investigated. This protease was successfully applied for the activation of purified pro-rMTG either as free or immobilized enzyme and the free enzyme was also applicable directly in the crude cell extract of E. coli. Thus, it enables a simple two-step activation/purification procedure resulting in protease-free and almost pure transglutaminase preparations. The protocol has been successfully applied to both, wild-type transglutaminase of Streptomyces mobaraensis as well as to the highly active variant S2P. Proteinase K activates the pro-rMTG without unwanted degradation of the histidine-tag. It turned out to be very important to inhibit proteinase K activity, e.g., by PMSF, prior to protein separation by SDS-PAGE.

  19. Gas desorption during friction of amorphous carbon films

    Science.gov (United States)

    Rusanov, A.; Fontaine, J.; Martin, J.-M.; Mogne, T. L.; Nevshupa, R.

    2008-03-01

    Gas desorption induced by friction of solids, i.e. tribodesorption, is one of the numerous physical and chemical phenomena, which arise during friction as result of thermal and structural activation of material in a friction zone. Tribodesorption of carbon oxides, hydrocarbons, and water vapours may lead to significant deterioration of ultra high vacuum conditions in modern technological equipment in electronic, optoelectronic industries. Therefore, knowledge of tribodesorption is crucial for the performance and lifetime of vacuum tribosystems. Diamond-like carbon (DLC) coatings are interesting materials for vacuum tribological systems due to their high wear resistance and low friction. Highly hydrogenated amorphous carbon (a-C:H) films are known to exhibit extremely low friction coefficient under high vacuum or inert environment, known as 'superlubricity' or 'superlow friction'. However, the superlow friction period is not always stable and then tends to spontaneous transition to high friction. It is supposed that hydrogen supply from the bulk to the surface is crucial for establishing and maintaining superlow friction. Thus, tribodesorption can serve also as a new technique to determine the role of gases in superlow friction mechanisms. Desorption of various a-C:H films, deposited by PECVD, ion-beam deposition and deposition using diode system, has been studied by means of ultra-high vacuum tribometer equipped with a mass spectrometer. It was found that in superlow friction period desorption rate was below the detection limit in the 0-85 mass range. However, transition from superlow friction to high friction was accompanied by desorption of various gases, mainly of H2 and CH4. During friction transition, surfaces were heavily damaged. In experiments with DLC films with low hydrogen content tribodesorption was significant during the whole experiment, while low friction was not observed. From estimation of maximum surface temperature during sliding contact it was

  20. Temperature Effect on Boron Adsorption—Desorption Kinetics in Soils

    Institute of Scientific and Technical Information of China (English)

    ZHUDUANWEI; SHILEI; 等

    1999-01-01

    The effect of temperature on the properties of boron adsorption-desorption in brown-red soil,yellowbrown soil and calcareous alluvial soil of Hubei Province was investigated with the mobile displacement technique.The experimental data of B adsorption-desorption amounts and reaction time at 25 and 40℃ were fitted by the zero-order,first-order and parabolic diffusion kinetic equations.The adsorption process was in conformity with the parabolic diffusion law at both the temperatures,and the values of rate constant of the parabolic diffusion equation in B adsorption were 0.138,0.124 and 0.105 mg kg-1 min-1/2 at 25℃,and 0.147,0.146and 0.135mg kg-1 min1/2 at 40℃ for the brown-red soil,yellow-brown soil,and calcareous alluvial soil,respectively,The relationship between amount of B desorption and reaction time could be well described by the first-order kinetic equation,and the corresponding values of rate constant were 0.0422,0.0563 and 0.0384min-1 at 25℃,and 0.0408,0.0423 and 0.0401min-1 at 40℃ for the brown-red soil,the yellow-brown soil and the calcareous alluvial soil,respectively.Therefore,the desorption process of B might be related to the amount of B adsorbed in soil,The higher th temperature,the lower the amount of B adsorption of the same soil in the same reaction time,The values of the apparent activation energy of B adsorption in the three soils calculated with the rate constants of parabolic diffusion equation were 3.27,8.44 and 12.99 kJ mol-1,respectively,based on the experimental data of B adsorption amounts and reaction time at and 40℃.

  1. Production of recombinant orange-spotted grouper (Epinephelus coioides) follicle-stimulating hormone (FSH) in single-chain form and dimer form by Pichia pastoris and their biological activities.

    Science.gov (United States)

    Chen, Jun; Zhang, Yanhong; Tang, Zhiguo; Mao, Jiewei; Kuang, Zhonglei; Qin, Chaobin; Li, Wensheng

    2012-09-01

    FSH is a key regulator of steroidogenesis and gonadal growth in teleosts. However, function of FSH is elusive in grouper due to the lack of purified and native FSH. In the present study, we reported production of bioactive orange-spotted grouper (Epinephelus coioides) FSH in dimer form and single-chain form by Pichia pastoris. Dimer form of recombinant grouper FSH (rgFSHba) was accomplished by co-expressing mature FSHb-subunit and a-subunit genes. Fusion of mature FSHb-subunit and a-subunit genes together linking with a polypeptide (4×(Gly-Ser)-Gly-Thr) gene generated single-chain form of recombinant grouper FSH (rgFSHb-a). Recombinant grouper common α-subunit (rgCga) and FSHb-subunit (rgFSHb) were also separately produced. Recombinant proteins were verified by Western blot and mass spectrometry assays, and characterized by deglycosylation analysis. Deglycosylation assay suggested that glycosylation of recombinant FSH mainly occurred on common a-subunit. Bioactivities of recombinant proteins were initially evaluated by activating grouper FSH receptor, and further demonstrated by incubating ovarian fragments of adult grouper and intraperitoneal injection in juvenile female grouper. Two forms of recombinant FSH presented similar biological activities of activating FSH receptor and stimulating in vitro testosterone (T) and estradiol-17β (E2) secretion, though the dimer form functioned slightly weaker than the single-chain form. However, injections of rgFSHb-a or rgFSHba could significantly increase serum T and E2 levels, induce early ovarian development, reduce hypothalamic gnrh1 mRNA level, and increase hypothalamic cyp19a1b mRNA level. Data in this study suggested that recombinant gonadotropin could be produced in dimer form or single-chain form by P. pastoris, and FSH could regulate steroidogenesis and early ovarian development in juvenile grouper.

  2. Critical appraisal of the role of recombinant activated factor VII in the treatment of hemophilia patients with inhibitors

    Directory of Open Access Journals (Sweden)

    Ampaiwan Chuansumrit

    2010-03-01

    Full Text Available Ampaiwan Chuansumrit1, Pantep Angchaisuksiri2, Nongnuch Sirachainan11Departments of Pediatrics and 2Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University,  Bangkok, ThailandAbstract: Hemophilia patients with inhibitors faced the constraint of inadequate treatment for several years before the era of recombinant factor VIIa (rFVII. Initially, rFVIIa was used in the compassionate-use programs. After a worldwide license was issued, more than 1.5 million doses were administered. Bleeding of joints and muscles was controlled effectively by means of an early home treatment program, with either a standard dose of 90 μg/kg every 2 to 3 hours for a few doses or a single dose of 270 μg/kg. For more serious bleeding episodes or minor surgery, an initial dose of 90 μg/kg was given every 2 hours for 24 to 48 hours followed by increased intervals of 3 to 6 hours according to the severity of bleeding and efficacy of bleeding control. In cases of major surgery such as orthopedic procedures, the same regimen can be applied except for a higher initial dose of 120 to 180 μg/kg. However, increasing the dose should be considered if there are unexpected bleeding complications since the half-life and clearance of rFVIIa differ between individuals. In addition, prophylaxis is administered to a small number of patients. Finally, the reported thromboembolic events found in hemophilia patients with inhibitors receiving rFVIIa are extremely low, much less than 1%.Keywords: bleeding disorder, hemophilia, inhibitor, NovoSeven, recombinant factor VIIa

  3. Desorption of 137Cs+ from mosses

    Directory of Open Access Journals (Sweden)

    OLGICA NEDIC

    2002-09-01

    Full Text Available Mosses are biomonitors that accumulate large amounts of various pollutants, including radionuclides. In this work we investigated the possibility of 137Cs extraction from mosses, as well as the significance of species specificity on the efficiency of 137Cs desorption. Salt and acid solutions were used as extraction media. It was shown that a 5 % solution of both ammonium oxalate and phosphoric acid was able to desorb 81.8 % of 137Cs+ from Homalothecium sericeum, which was 39.9 % more than desorption from water. At the same time, most of the desorbed 137Cs+ was incorporated in crystals that precipitated from the solution. An interspecies difference in respect to 137Cs+ desorption was noticed.

  4. Adsorption and Desorption of Methiopyrsulfuron in Soils

    Institute of Scientific and Technical Information of China (English)

    WU Chun-Xian; WANG Jin-Jun; ZHANG Su-Zhi; ZHANG Zhong-Ming

    2011-01-01

    Methiopyrsulfuron is a new low-rate sulfonylurea herbicide for weed control in wheat; however, there is a lack of published information on its behavior in soils. In this study, methiopyrsulfuron adsorption and desorption were measured in seven soils sampled from Heilongjiang, Shandong, Jiangxi, Sichuan, Anhui, and Chongqing provinces of China using a batch equilibrium method. The Freundlich equation was used to described its adsorption and desorption. Adsorption isotherms were nonlinear with the values of Kf-ads, the Freundlich empirical constant indicative of the adsorption capacity,ranging from 0.75 to 2.46, suggesting that little of this herbicide was adsorbed by any of the seven soils. Soil pH and organic matter content (OM) were the main factors influencing adsorption; adsorption was negatively correlated with pH and positively correlated with OM. Methiopyrsulfuron desorption was hysteretic on the soils with high OM content and low pH.

  5. Dielectronic recombination of Fe 3p^q ions: a key ingredient for describing X-ray absorption in active galactic nuclei

    CERN Document Server

    Badnell, N R

    2006-01-01

    We have carried-out multi-configuration Breit-Pauli AUTOSTRUCTURE calculations for the dielectronic recombination (DR) of Fe^{8+} - Fe^{12+} ions. We obtain total DR rate coefficients for the initial ground-level which are an order of magnitude larger than those corresponding to radiative recombination (RR), at temperatures where Fe 3p^q (q=2-6) ions are abundant in photoionized plasmas. The resultant total (DR+RR) rate coefficients are then an order of magnitude larger than those currently in use by photoionized plasma modeling codes such as CLOUDY, ION and XSTAR. These rate coefficients, together with our previous results for q=0 and 1, are critical for determining the ionization balance of the M-shell Fe ions which give rise to the prominent unresolved-transition-array X-ray absorption feature found in the spectrum of many active galactic nuclei. This feature is poorly described by CLOUDY and ION, necessitating an ad hoc modification to the low-temperature DR rate coefficients. Such modifications are no lo...

  6. Expression of biologically active recombinant equine interferon-gamma by two different baculovirus gene expression systems using insect cells and silkworm larvae.

    Science.gov (United States)

    Wu, Donglai; Murakami, Kenji; Liu, Nihong; Inoshima, Yasuo; Yokoyama, Takashi; Kokuho, Takehiro; Inumaru, Shigeki; Matsumura, Tomio; Kondo, Takashi; Nakano, Katsushige; Sentsui, Hiroshi

    2002-10-21

    The full-length equine interferon-gamma (eIFN-gamma) cDNA, including the secretion signal peptide coding region, was recloned into baculovirus transfer vector pAcYM1. This vector was co-transfected with Autographa californica nuclear polyhedrosis virus DNA or hybrid nuclear polyhedrosis virus DNA into Spodoptera frugiperda cells. The recombinant viruses, named AcEIFN-gamma and HyEIFN-gamma, were then recovered. Recombinant eIFN-gamma (reIFN-gamma) was accumulated in the culture fluid of the AcEIFN-gamma or HyEIFN-gamma infected Tricoplusia ni -derived cell line, BTI TN 5B1-4, and hemolymph of HyEIFN-gamma infected silkworm larvae. These reIFN-gamma forms were shown to be 14, 16, 18 and 20kDa proteins, and glycosylated as confirmed by SDS-PAGE and tunicamycin treatment. Both reIFN-gamma proteins, showed high-level biological activities to vesicular stomatitis virus by cytopathic effect reduction assay, and MHC class II antigen induction on the equine fetal kidney-78 cell line. PMID:12445800

  7. Production of biologically active recombinant bovine interferon-gamma by two different baculovirus gene expression systems using insect cells and silkworm larvae.

    Science.gov (United States)

    Murakami, K; Uchiyama, A; Kokuho, T; Mori, Y; Sentsui, H; Yada, T; Tanigawa, M; Kuwano, A; Nagaya, H; Ishiyama, S; Kaki, H; Yokomizo, Y; Inumaru, S

    2001-01-01

    The full-length bovine interferon-gamma (bIFN-gamma) cDNA, including the secretion signal peptide coding region was recloned into baculovirus transfer vectors pAcYM1 and pBm050. These vectors were co-transfected with Autographa californica nuclear polyhedrosis virus (AcNPV) or Bombyx mori nuclear polyhedrosis virus (BmNPV) DNA into Spodoptera frugiperda cells (SF21AE) and Bombyx mori cells (BmN), respectively. The recombinant viruses, named AcBIFN-gamma and BmBIFN-gamma, were then recovered. Recombinant bIFN-gamma (rbIFN-gamma) was accumulated in the culture fluid of AcBIFN-gamma-infected Trichoplusia ni cells and BmBIFN-gamma-infected silkworm larvae. These rbIFN-gamma forms were shown to be glycosylated 20 and 22 kDa proteins as confirmed by SDS-PAGE and tunicamycin treatment. These products were sensitive to cystein proteinase. Both rbIFN-gamma proteins, showed high-level biological activities by plaque reduction assay using vesicular stomatitis virus, and MHC class II antigen induction on bovine macrophage cells. PMID:11145838

  8. Electronic Desorption of gas from metals

    Energy Technology Data Exchange (ETDEWEB)

    Molvik, A W; Kollmus, H; Mahner, E; Covo, M K; Bender, M; Bieniosek, F M; Kramer, A; Kwan, J; Prost, L; Seidl, P A; Westenskow, G

    2006-11-02

    During heavy ion operation in several particle accelerators world-wide, dynamic pressure rises of orders of magnitude were triggered by lost beam ions that bombarded the vacuum chamber walls. This ion-induced molecular desorption, observed at CERN, GSI, and BNL, can seriously limit the ion beam lifetime and intensity of the accelerator. From dedicated test stand experiments we have discovered that heavy-ion induced gas desorption scales with the electronic energy loss (dE{sub e}/dx) of the ions slowing down in matter; but it varies only little with the ion impact angle, unlike electronic sputtering.

  9. Recombinant Collagenlike Proteins

    Science.gov (United States)

    Fertala, Andzej

    2007-01-01

    A group of collagenlike recombinant proteins containing high densities of biologically active sites has been invented. The method used to express these proteins is similar to a method of expressing recombinant procollagens and collagens described in U. S. Patent 5,593,859, "Synthesis of human procollagens and collagens in recombinant DNA systems." Customized collagenous proteins are needed for biomedical applications. In particular, fibrillar collagens are attractive for production of matrices needed for tissue engineering and drug delivery. Prior to this invention, there was no way of producing customized collagenous proteins for these and other applications. Heretofore, collagenous proteins have been produced by use of such biological systems as yeasts, bacteria, and transgenic animals and plants. These products are normal collagens that can also be extracted from such sources as tendons, bones, and hides. These products cannot be made to consist only of biologically active, specific amino acid sequences that may be needed for specific applications. Prior to this invention, it had been established that fibrillar collagens consist of domains that are responsible for such processes as interaction with cells, binding of growth factors, and interaction with a number of structural proteins present in the extracellular matrix. A normal collagen consists of a sequence of domains that can be represented by a corresponding sequence of labels, e.g., D1D2D3D4. A collagenlike protein of the present invention contains regions of collagen II that contain multiples of a single domain (e.g., D1D1D1D1 or D4D4D4D4) chosen for its specific biological activity. By virtue of the multiplicity of the chosen domain, the density of sites having that specific biological activity is greater than it is in a normal collagen. A collagenlike protein according to this invention can thus be made to have properties that are necessary for tissue engineering.

  10. STM-Induced Hydrogen Desorption via a Hole Resonance

    DEFF Research Database (Denmark)

    Stokbro, Kurt; Thirstrup, C.; Sakurai, M.;

    1998-01-01

    We report STM-induced desorption of H from Si(100)-H(2 X 1) at negative sample bias. The desorption rate exhibits a power-law dependence on current and a maximum desorption rate at -7 V. The desorption is explained by vibrational heating of H due to inelastic scattering of tunneling holes...... with the Si-H 5 sigma hole resonance. The dependence of desorption rate on current and bias is analyzed using a novel approach for calculating inelastic scattering, which includes the effect of the electric field between tip and sample. We show that the maximum desorption rate at -7 V is due to a maximum...

  11. Recombinant Technology and Probiotics

    Directory of Open Access Journals (Sweden)

    Icy D’Silva

    2011-09-01

    Full Text Available Recombinant technology has led the way to monumental advances in the development of useful molecules, including the development of safe probiotics. The development of novel approaches using recombinant technology and probiotics that allow accurate targeting of therapeutics to the mucosa is an interesting area of research. The creation and use of recombinant probiotics expressing recombinantovalbumin, recombinant ovalbumin mutants and yet-to-be-designed recombinant hypo/non-allergenic molecules offer the opportunity to further investigate their effects for food, nutrition, environment andhealth. This review highlights advances in native probiotics and recombinant probiotics expressing native and recombinant molecules for food, nutrition, environment and health.

  12. Recombinant Treponema pallidum protein Tp0965 activates endothelial cells and increases the permeability of endothelial cell monolayer.

    Directory of Open Access Journals (Sweden)

    Rui-Li Zhang

    Full Text Available The recombinant Treponema pallidum protein Tp0965 (rTp0965, one of the many proteins derived from the genome of T. pallidum subsp. pallidum, shows strong immunogenicity and immunoreactivity. In this study, we investigated the effects of rTp0965 on the endothelial barrier. Treatment of human umbilical vein endothelial cells (HUVECs with rTp0965 resulted in increased levels of ICAM-1, E-selectin, and MCP-1 mRNA and protein expression. These increases contributed to the adhesion and chemataxis of monocytes (THP-1 cells to HUVECs preincubated with rTp0965. In addition, rTp0965 induced reorganization of F-actin and decreased expression of claudin-1 in HUVECs. Interestingly, inhibition of the RhoA/ROCK signal pathway protected against rTp0965-induced higher endothelial permeability as well as transendothelial migration of monocytes. These data indicate that Tp0965 protein may play an important role in the immunopathogenesis of syphilis.

  13. Understanding Recombination.

    Science.gov (United States)

    Zimmerman, Ira

    2003-01-01

    Describes a science activity on the importance of meiosis for variability. Uses a coin flip to demonstrate the random arrangement of genetic materials and explains how this results in zygotes with a new DNA combination. (YDS)

  14. Treatment of neonatal fungal infective endocarditis with recombinant tissue plasminogen: activator in a low birth weight infant case report and review of the literature.

    Science.gov (United States)

    Babayigit, Aslan; Cebeci, Burcu; Buyukkale, Gokhan; Semerci, Seda Yılmaz; Bornaun, Helen; Oztarhan, Kazim; Gokce, Muge; Cetinkaya, Merih

    2015-10-01

    With advances in medical sciences, an increase in survival rates of low birth weight; increased incidence in use of catheter and antibiotics, and total parenteral nutrition are reported, therefore, the rate of fungal infections in late and very late onset neonatal sepsis have increased. Although fungal endocarditis rarely occur in newborns, it has a high morbidity and mortality. Antifungal therapy is often insufficient in cases who develop fungal endocarditis and surgical treatment is not preferred due to its difficulty and high mortality. Herein, fungal endocarditis in a preterm newborn treated with single-dose recombinant tissue plasminogen activator in addition to antifungal therapy is presented and relevant literature has been reviewed. The vegetation completely disappeared following treatment and no complication was observed.

  15. Magnesium growth in magnesium deuteride thin films during deuterium desorption

    Energy Technology Data Exchange (ETDEWEB)

    Checchetto, R., E-mail: riccardo.checchetto@unitn.it [Dipartimento di Fisica and CNISM, Università di Trento, Via Sommarive 14, I-38123 Trento (Italy); Miotello, A. [Dipartimento di Fisica and CNISM, Università di Trento, Via Sommarive 14, I-38123 Trento (Italy); Mengucci, P.; Barucca, G. [Dipartimento di Fisica e Ingegneria dei Materiali e del Territorio, Università Politecnica delle Marche, I-60131 Ancona (Italy)

    2013-12-15

    Highlights: ► Highly oriented Pd-capped magnesium deuteride thin films. ► The MgD{sub 2} dissociation was studied at temperatures not exceeding 100 °C. ► The structure of the film samples was analyzed by XRD and TEM. ► The transformation is controlled by the re-growth velocity of the Mg layers. ► The transformation is thermally activated, activation energy value of 1.3 ± 0.1 eV. -- Abstract: Pd- capped nanocrystalline magnesium thin films having columnar structure were deposited on Si substrate by e-gun deposition and submitted to thermal annealing in D{sub 2} atmosphere to promote the metal to deuteride phase transformation. The kinetics of the reverse deuteride to metal transformation was studied by Thermal Desorption Spectroscopy (TDS) while the structure of the as deposited and transformed samples was analyzed by X-rays diffraction and Transmission Electron Microscopy (TEM). In Pd- capped MgD{sub 2} thin films the deuteride to metal transformation begins at the interface between un-reacted Mg and transformed MgD{sub 2} layers. The D{sub 2} desorption kinetics is controlled by MgD{sub 2}/Mg interface effects, specifically the re-growth velocity of the Mg layers. The Mg re-growth has thermally activated character and shows an activation energy value of 1.3 ± 0.1 eV.

  16. Quantum theory of laser-stimulated desorption

    Science.gov (United States)

    Slutsky, M. S.; George, T. F.

    1978-01-01

    A quantum theory of laser-stimulated desorption (LSDE) is presented and critically analyzed. It is shown how LSDE depends on laser-pulse characteristics and surface-lattice dynamics. Predictions of the theory for a Debye model of the lattice dynamics are compared to recent experimental results.

  17. A microsystems enabled field desorption source.

    Energy Technology Data Exchange (ETDEWEB)

    Hertz, Kristin L.; Resnick, Paul James; Schwoebel, Paul R. (University of New Mexico, Albuquerque, NM); Holland, Christopher E. (SRI International, Menlo Park, CA); Chichester, David L. (Idaho National Laboratory, Idaho Falls, ID)

    2010-07-01

    Technologies that have been developed for microelectromechanical systems (MEMS) have been applied to the fabrication of field desorption arrays. These techniques include the use of thick films for enhanced dielectric stand-off, as well as an integrated gate electrode. The increased complexity of MEMS fabrication provides enhanced design flexibility over traditional methods.

  18. Potency of Full- Length MGF to Induce Maximal Activation of the IGF-I R Is Similar to Recombinant Human IGF-I at High Equimolar Concentrations.

    Directory of Open Access Journals (Sweden)

    Joseph A M J L Janssen

    Full Text Available To compare full-length mechano growth factor (full-length MGF with human recombinant insulin-like growth factor-I (IGF-I and human recombinant insulin (HI in their ability to activate the human IGF-I receptor (IGF-IR, the human insulin receptor (IR-A and the human insulin receptor-B (IR-B, respectively. In addition, we tested the stimulatory activity of human MGF and its stabilized analog Goldspink-MGF on the IGF-IR.The effects of full-length MGF, IGF-I, human mechano growth factor (MGF, Goldspink-MGF and HI were compared using kinase specific receptor activation (KIRA bioassays specific for IGF-I, IR-A or IR-B, respectively. These assays quantify activity by measuring auto-phosphorylation of the receptor upon ligand binding.IGF-IR: At high equimolar concentrations maximal IGF-IR stimulating effects generated by full-length MGF were similar to that of IGF-I (89-fold vs. 77-fold, respectively. However, EC50 values of IGF-I and full-length MGF for the IGF-I receptor were 0.86 nmol/L (95% CI 0.69-1.07 and 7.83 nmol/L (95% CI: 4.87-12.58, respectively. No IGF-IR activation was observed by human MGF and Goldspink-MGF, respectively. IR-A/IR-B: At high equimolar concentrations similar maximal IR-A stimulating effects were observed for full -length MGF and HI, but maximal IR-B stimulation achieved by full -length MGF was stronger than that by HI (292-fold vs. 98-fold. EC50 values of HI and full-length MGF for the IR-A were 1.13 nmol/L (95% CI 0.69-1.84 and 73.11 nmol/L (42.87-124.69, respectively; for IR-B these values were 1.28 nmol/L (95% CI 0.64-2.57 and 35.10 nmol/L (95% 17.52-70.33, respectively.Full-length MGF directly stimulates the IGF-IR. Despite a higher EC50 concentration, at high equimolar concentrations full-length MGF showed a similar maximal potency to activate the IGF-IR as compared to IGF-I. Further research is needed to understand the actions of full-length MGF in vivo and to define the physiological relevance of our in vitro findings.

  19. Potency of Full- Length MGF to Induce Maximal Activation of the IGF-I R Is Similar to Recombinant Human IGF-I at High Equimolar Concentrations

    Science.gov (United States)

    Janssen, Joseph A. M. J. L.; Hofland, Leo J.; Strasburger, Christian J.; van den Dungen, Elisabeth S. R.; Thevis, Mario

    2016-01-01

    Aims To compare full-length mechano growth factor (full-length MGF) with human recombinant insulin-like growth factor-I (IGF-I) and human recombinant insulin (HI) in their ability to activate the human IGF-I receptor (IGF-IR), the human insulin receptor (IR-A) and the human insulin receptor-B (IR-B), respectively. In addition, we tested the stimulatory activity of human MGF and its stabilized analog Goldspink-MGF on the IGF-IR. Methods The effects of full-length MGF, IGF-I, human mechano growth factor (MGF), Goldspink-MGF and HI were compared using kinase specific receptor activation (KIRA) bioassays specific for IGF-I, IR-A or IR-B, respectively. These assays quantify activity by measuring auto-phosphorylation of the receptor upon ligand binding. Results IGF-IR: At high equimolar concentrations maximal IGF-IR stimulating effects generated by full-length MGF were similar to that of IGF-I (89-fold vs. 77-fold, respectively). However, EC50 values of IGF-I and full-length MGF for the IGF-I receptor were 0.86 nmol/L (95% CI 0.69–1.07) and 7.83 nmol/L (95% CI: 4.87–12.58), respectively. No IGF-IR activation was observed by human MGF and Goldspink-MGF, respectively. IR-A/IR-B: At high equimolar concentrations similar maximal IR-A stimulating effects were observed for full -length MGF and HI, but maximal IR-B stimulation achieved by full -length MGF was stronger than that by HI (292-fold vs. 98-fold). EC50 values of HI and full-length MGF for the IR-A were 1.13 nmol/L (95% CI 0.69–1.84) and 73.11 nmol/L (42.87–124.69), respectively; for IR-B these values were 1.28 nmol/L (95% CI 0.64–2.57) and 35.10 nmol/L (95% 17.52–70.33), respectively. Conclusions Full-length MGF directly stimulates the IGF-IR. Despite a higher EC50 concentration, at high equimolar concentrations full-length MGF showed a similar maximal potency to activate the IGF-IR as compared to IGF-I. Further research is needed to understand the actions of full-length MGF in vivo and to define the

  20. Sorption/desorption kinetics of contaminants on mobile particles: Modeling and experimental evidence

    Science.gov (United States)

    Bold, Steffen; Kraft, Siegfried; Grathwohl, Peter; Liedl, Rudolf

    2003-12-01

    In this study the impact of sorption/desorption kinetics between organic contaminants and mobile particles suspended in subsurface water is analyzed. TCE migration through a granular activated carbon column is investigated at different transport velocities with lignite and activated carbon particles as mobile carriers. The measured breakthrough characteristics of TCE can be reproduced by a reactive transport model simulating sorption/desorption kinetics applying an intraparticle diffusion approach for mobile particles and the packed bed of granular activated carbon. Model predictions are based on independently measured physicochemical parameters, i.e., no calibration of TCE sorption/desorption is required. The close matches of experimental data to predicted data validate the exclusively process-based model assumptions and indicate that this approach has large predictive capabilities. Extending these findings, a sensitivity study is presented in order to specify under which conditions sorption/desorption of contaminants in mobile particles has to be modeled as a kinetic process. It is found that sorption/desorption kinetics are of major importance for Damköhler numbers between 0.01 and 100.

  1. The effect of chars and their water extractable organic carbon (WEOC) fractions on atrazine adsorption-desorption processes

    Science.gov (United States)

    Cavoski, I.; Jablonowski, N.; Burauel, P.; Miano, T.

    2012-04-01

    Chars are carbonaceous material produced from different type of biomass by pyrolysis. They are known as highly effective adsorbents for atrazine therefore limiting its degradation and its diffusion into the aqueous phase. The aim of the present work is to study the effects of different chars and char's derived WEOC on atrazine sorption-desorption processes. The five chars been used in this study derived from: 1) fast pyrolysis from hard wood (FP1); 2) flash pyrolysis from soft wood (FP2); 3) slow pyrolysis from deciduous wood (CC); 4) gasification from deciduous wood (GC) and 5) the market, purchased as activated charcoal standard (AC). Short-term batch equilibration tests were conducted to assess the sorption-desorption behavior of 14C-labeled atrazine on the chars, with a special focus on the desorption behavior using successive dilution method with six consecutive desorption step. Chars and their WEOC were physically and chemically characterized. Results demonstrate that biomass and pyrolysis process used to produce chars affect their physical and chemical properties, and atrazine adsorption-desorption behavior. Atrazine desorption resulted from the positive and competitive interactions between WEOC and chars surfaces. WEOC pool play important role in atrazine adsorption-desorption behavior. FP1 and FP2 with higher concentration of WEOC showed higher desorption rates, whereas GC, CC and AC with insignificant WEOC concentration strongly adsorb atrazine with low desorption rates. According to our results, when high WEOC pools chars are concerned, an increase in atrazine desorption can be observed but further studies would help in confirming the present results.

  2. Heterologous Expression of MeLEA3: A 10 kDa Late Embryogenesis Abundant Protein of Cassava, Confers Tolerance to Abiotic Stress in Escherichia coli with Recombinant Protein Showing In Vitro Chaperone Activity.

    Science.gov (United States)

    Barros, Nicolle L F; da Silva, Diehgo T; Marques, Deyvid N; de Brito, Fabiano M; dos Reis, Savio P; de Souza, Claudia R B

    2015-01-01

    Late embryogenesis abundant (LEA) proteins are small molecular weight proteins involved in acquisition of tolerance to drought, salinity, high temperature, cold, and freezing stress in many plants. Previous studies revealed a cDNA sequence coding for a 10 kDa atypical LEA protein, named MeLEA3, predicted to be located into mitochondria with potential role in salt stress response of cassava (Manihot esculenta Crantz). Here we aimed to produce the recombinant MeLEA3 protein by heterologous expression in Escherichia coli and evaluate the tolerance of bacteria expressing this protein under abiotic stress. Our result revealed that the recombinant MeLEA3 protein conferred a protective function against heat and salt stress in bacterial cells. Also, the recombinant MeLEA3 protein showed in vitro chaperone activity by protection of NdeI restriction enzyme activity under heat stress. PMID:25990084

  3. Requirement of 8-mercaptoguanosine as a costimulus for IL-4-dependent μ to γ1 class switch recombination in CD38-activated B cells

    International Nuclear Information System (INIS)

    Mature B-2 cells expressing surface IgM and IgD proliferate upon stimulation by CD38, CD40 or lipopolysaccharide (LPS) and differentiate into IgG1-producing plasma cells in the presence of cytokines. The process of class switch recombination (CSR) from IgM to other isotypes is highly regulated by cytokines and activation-induced cytidine deaminase (AID). Blimp-1 and XBP-1 play an essential role in the terminal differentiation of switched B-2 cells to Ig-producing plasma cells. IL-5 induces AID and Blimp-1 expression in CD38- and CD40-activated B-2 cells, leading to μ to γ1 CSR at DNA level and IgG1 production. IL-4, a well-known IgG1-inducing factor, does not induce μ to γ1 CSR in CD38-activated B-2 cells or Blimp-1, while IL-4 induces μ to γ1 CSR, XBP-1 expression, and IgG1 production expression in CD40-activated B-2 cells. Interestingly, the addition of 8-mercaptoguanosine (8-SGuo) with IL-4 to the culture of CD38-activated B cells can induce μ to γ1 CSR, Blimp-1 expression, and IgG1 production. Intriguingly, 8-SGuo by itself induces AID expression in CD38-activated B cells. However, it does not induce μ to γ1 CSR. These results imply that the mode of B-cell activation for extracellular stimulation affects the outcome of cytokine stimulation with respect to the efficiency and direction of CSR, and the requirements of the transcriptional regulator and the generation of antibody-secreting cells. Furthermore, our data suggest the requirement of additional molecules in addition to AID for CSR

  4. Cloning of PEPC-1 from a C4 halophyte Suaeda aralocaspica without Kranz anatomy and its recombinant enzymatic activity in responses to abiotic stresses.

    Science.gov (United States)

    Cheng, Gang; Wang, Lu; Lan, Haiyan

    2016-02-01

    Phosphoenolpyruvate carboxylase (PEPC) is a key enzyme of C4 photosynthetic pathway and plays an important biochemical role in higher plants and micro organisms. To gain understanding of the role of PEPC in stress adaptation in plant, we cloned PEPC gene from Suaeda aralocaspica, a C4 species without Kranz anatomy, and performed a series of experiments with PEPC gene expressed in Escherichia coli under various abiotic stresses. Results showed that, based on the homology cloning and 5'-RACE technique, the full-length cDNA sequence of PEPC (2901 bp) from S. aralocaspica was obtained, which shares the typical conserved domains to documented PEPCs and was identified as PEPC-1 in accord to the reported partial sequence (ppc-1) in S. aralocaspica. qRT-PCR analysis revealed the expression patterns of PEPC-1 and PEPC-2 (known as ppc-2, another plant type of PEPC) in S. aralocaspica, suggesting that PEPC-1 was up-regulated during seed germination and under NaCl stress, and presented higher level in chlorenchyma than other tissues, which were significantly different with PEPC-2. Afterwards, PEPC-1 was recombinant in E. coli (pET-28a-PEPC) and expressed as an approximate 110 kDa protein. Under various abiotic stresses, the recombinant E. coli strain harboring with PEPC-1 showed significant advantage in growth at 400-800 mmol L(-1) NaCl, 10-20% PEG6000, 25 and 30 °C lower temperature, 50-200 μmol L(-1) methyl viologen, and pH 5.0 and 9.0 condition, compared to control. Further analysis of the enzymatic characteristics of the recombinant PEPC-1 suggests that it was the higher enzyme activity of PEPC-1 which might confer the stress tolerance to E. coli. We speculate that over expression of PEPC-1 is probably related to regulation of oxaloacetate (OAA) in tricarboxylic acid (TCA) cycle in E. coli, which may contribute to further understanding of the physiological function of PEPC in S. aralocaspica. PMID:26777251

  5. Residence time dependent desorption of Staphylococcus epidermidis from hydrophobic and hydrophilic substrata

    NARCIS (Netherlands)

    Boks, N.P.; Kaper, H.J.; Norde, W.; Busscher, H.J.; Mei, van der H.C.

    2008-01-01

    Adhesion and desorption are simultaneous events during bacterial adhesion to surfaces. although desorption is far less studied than adhesion. Here, desorption of Staphylococcus epidermidis from substratum surfaces is demonstrated to be residence time dependent. Initial desorption rate coefficients w

  6. Recombinant production of biologically active giant grouper (Epinephelus lanceolatus) growth hormone from inclusion bodies of Escherichia coli by fed-batch culture.

    Science.gov (United States)

    Chung, Wen-Jen; Huang, Chi-Lung; Gong, Hong-Yi; Ou, Tsung-Yin; Hsu, Jue-Liang; Hu, Shao-Yang

    2015-06-01

    Growth hormone (GH) performs important roles in regulating somatic growth, reproduction, osmoregulation, metabolism and immunity in teleosts, and thus, it has attracted substantial attention in the field of aquaculture application. Herein, giant grouper GH (ggGH) cDNA was cloned into the pET28a vector and expressed in Shuffle® T7 Competent Escherichia coli. Recombinant N-terminal 6× His-tagged ggGH was produced mainly in insoluble inclusion bodies; the recombinant ggGH content reached 20% of total protein. For large-scale ggGH production, high-cell density E. coli culture was achieved via fed-batch culture with pH-stat. After 30h of cultivation, a cell concentration of 41.1g/l dry cell weight with over 95% plasmid stability was reached. Maximal ggGH production (4.0g/l; 22% total protein) was achieved via mid-log phase induction. Various centrifugal forces, buffer pHs and urea concentrations were optimized for isolation and solubilization of ggGH from inclusion bodies. Hydrophobic interactions and ionic interactions were the major forces in ggGH inclusion body formation. Complete ggGH inclusion body solubilization was obtained in PBS buffer at pH 12 containing 3M urea. Through a simple purification process including Ni-NTA affinity chromatography and refolding, 5.7mg of ggGH was obtained from 10ml of fed-batch culture (45% recovery). The sequence and secondary structure of the purified ggGH were confirmed by LC-MS/MS mass spectrometry and circular dichroism analysis. The cell proliferation-promoting activity was confirmed in HepG2, ZFL and GF-1 cells with the WST-1 colorimetric bioassay. PMID:25703054

  7. The recombination activation gene 1 (Rag1 is expressed in a subset of zebrafish olfactory neurons but is not essential for axon targeting or amino acid detection

    Directory of Open Access Journals (Sweden)

    Friedrich Rainer W

    2005-07-01

    Full Text Available Abstract Background Rag1 (Recombination activation gene-1 mediates genomic rearrangement and is essential for adaptive immunity in vertebrates. This gene is also expressed in the olfactory epithelium, but its function there is unknown. Results Using a transgenic zebrafish line and immunofluorescence, we show that Rag1 is expressed and translated in a subset of olfactory sensory neurons (OSNs. Neurons expressing GFP under the Rag1 promoter project their axons to the lateral region of the olfactory bulb only, and axons with the highest levels of GFP terminate in a single glomerular structure. A subset of GFP-expressing neurons contain Gαo, a marker for microvillous neurons. None of the GFP-positive neurons express Gαolf, Gαq or the olfactory marker protein OMP. Depletion of RAG1, by morpholino-mediated knockdown or mutation, did not affect axon targeting. Calcium imaging indicates that amino acids evoke chemotopically organized glomerular activity patterns in a Rag1 mutant. Conclusion Rag1 expression is restricted to a subpopulation of zebrafish olfactory neurons projecting to the lateral olfactory bulb. RAG1 catalytic activity is not essential for axon targeting, nor is it likely to be required for regulation of odorant receptor expression or the response of OSNs to amino acids.

  8. Multiple angiopoietin recombinant proteins activate the Tie1 receptor tyrosine kinase and promote its interaction with Tie2

    OpenAIRE

    Saharinen, Pipsa; Kerkelä, Katja; Ekman, Niklas; Marron, Marie; Brindle, Nicholas; Lee, Gyun Min; Augustin, Hellmut; Koh, Gou Young; Alitalo, Kari

    2005-01-01

    The Tie1 receptor tyrosine kinase was isolated over a decade ago, but so far no ligand has been found to activate this receptor. Here, we have examined the potential of angiopoietins, ligands for the related Tie2 receptor, to mediate Tie1 activation. We show that a soluble Ang1 chimeric protein, COMP-Ang1, stimulates Tie1 phosphorylation in endothelial cells with similar kinetics and angiopoietin dose dependence when compared with Tie2. The phosphorylation of overexpressed Tie1 was weakly ind...

  9. Daedalus: a robust, turnkey platform for rapid production of decigram quantities of active recombinant proteins in human cell lines using novel lentiviral vectors

    OpenAIRE

    Bandaranayake, Ashok D.; Correnti, Colin; Ryu, Byoung Y.; Brault, Michelle; Strong, Roland K.; Rawlings, David J.

    2011-01-01

    A key challenge for the academic and biopharmaceutical communities is the rapid and scalable production of recombinant proteins for supporting downstream applications ranging from therapeutic trials to structural genomics efforts. Here, we describe a novel system for the production of recombinant mammalian proteins, including immune receptors, cytokines and antibodies, in a human cell line culture system, often requiring

  10. Recombinant DNA in Medicine

    OpenAIRE

    Cederbaum, Stephen D.; Fareed, George C.; Lovett, Michael A.; Shapiro, Larry J.

    1984-01-01

    Studies in bacteria and bacterial viruses have led to methods to manipulate and recombine DNA in unique and reproducible ways and to amplify these recombined molecules millions of times. Once properly identified, the recombinant DNA molecules can be used in various ways useful in medicine and human biology. There are many applications for recombinant DNA technology. Cloned complementary DNA has been used to produce various human proteins in microorganisms. Insulin and growth hormone have been...

  11. Improving baculovirus recombination

    OpenAIRE

    Zhao, Yuguang; Chapman, David A. G.; Jones, Ian M.

    2003-01-01

    Recombinant baculoviruses have established themselves as a favoured technology for the high-level expression of recombinant proteins. The construction of recombinant viruses, however, is a time consuming step that restricts consideration of the technology for high throughput developments. Here we use a targeted gene knockout technology to inactivate an essential viral gene that lies adjacent to the locus used for recombination. Viral DNA prepared from the knockout fails to initiate an infecti...

  12. Anti-tumor efficacy of lymphokine-activated killer cells and recombinant interleukin 2 in vivo: direct correlation between reduction of established metastases and cytolytic activity of lymphokine-activated killer cells

    International Nuclear Information System (INIS)

    Our previous studies demonstrated that the incubation of human peripheral blood lymphocytes or murine splenocytes in recombinant interleukin 2 (RIL 2) resulted in the generation of lymphokine-activated killer (LAK) cells capable of lysing a broad spectrum of fresh tumors in short-term chromium-release assays. Moreover, injections of LAK cells plus RIL 2 were highly effective in eliminating established 3 day metastases in the lung and liver. We have examined several parameters to define whether or not the cytolytic activity of LAK cells as measured in vitro correlated directly with the in vivo anti-tumor efficacy of adoptively transferred LAK cells. LAK cells plus RIL 2 could mediate marked reductions of established pulmonary metastases in mice rendered T cell deficient by adult thymectomy and lethal, total body irradiation followed by reconstitution with T cell-depleted bone marrow and spleen cells. Thus there was no requirement for additional T lymphocytes of host origin for successful therapy with adoptively transferred LAK cells plus RIL 2. Fresh splenocytes depleted of T cells by anti-Thy-1.2 monoclonal antibody plus complement generated LAK cells that were as highly lytic to fresh tumor in vitro and were as effective in reducing established pulmonary metastases as those generated from untreated or complement-treated splenocytes. Thus, the precursor to LAK cells with anti-tumor activity in vitro and in vivo did not express the Thy-1 antigenic marker. In contrast, treatment of LAK effector cells (those generated from a 3-day incubation of fresh, normal splenocytes in RIL 2) with anti-Thy-1.2 antibody plus complement reduced or abolished their in vitro cytolytic activity

  13. Recombinant human brain natriuretic peptide attenuates LPS-induced cellular injury in human fetal lung fibroblasts via inhibiting MAPK and NF-κB pathway activation.

    Science.gov (United States)

    Song, Zhi; Zhao, Xiu; Liu, Martin; Jin, Hongxu; Cui, Yan; Hou, Mingxiao; Gao, Yan

    2016-08-01

    Inflammatory responses are vital in lung injury diseases, particularly acute respiratory distress syndrome (ARDS). Recombinant human brain natriuretic peptide (rhBNP) has been shown to exhibit anti‑inflammatory effects in vivo in our previous studies. The present study aimed to investigate the mechanisms underlying the anti‑inflammatory effects of rhBNP on lipopolysaccharide (LPS)-induced human fetal lung fibroblasts (HFL-1). The results showed that LPS induced a significant increase in the leakage of lactate dehydrogenase and the secretion of interleukin (IL)‑1β. Activation of p38, extracellular-signal regulated kinase (ERK) 1/2, c‑Jun NH2-terminal kinase (JNK) mitogen‑activated protein kinases (MAPK)s, and nuclear factor (NF)‑κB in HFL‑1 cells was also observed following treatment with LPS. Treatment with rhBNP (0.1 µM) reduced the production of IL‑1β at the protein and mRNA levels. Moreover, rhBNP decreased the phosphorylation of p38, ERK1/2 and JNK induced by LPS. However, the JNK inhibitor, SP600125, significantly inhibited LPS‑induced IL‑1β production. These results indicate that the inhibition of IL‑1β by may dependent upon the JNK signaling pathway. The LPS‑induced NF‑κB activation was also suppressed by rhBNP, and IL‑1β production was inhibited by the NF‑κB inhibitor. Furthermore, NF‑κB activation was attenuated by the JNK inhibitor, indicating that NF‑κB activation was dependent on the JNK signaling pathway. The present study suggests that rhBNP exhibits an anti‑inflammatory effect on LPS‑induced HFL‑1 cell injury via the inhibition of MAPK and NF‑κB signaling pathways and may exhibit therapeutic potential for acute lung injury and ARDS. PMID:27314600

  14. Sample Desorption/Onization From Mesoporous Silica

    Science.gov (United States)

    Iyer, Srinivas; Dattelbaum, Andrew M.

    2005-10-25

    Mesoporous silica is shown to be a sample holder for laser desorption/ionization of mass spectrometry. Supported mesoporous silica was prepared by coating an ethanolic silicate solution having a removable surfactant onto a substrate to produce a self-assembled, ordered, nanocomposite silica thin film. The surfactant was chosen to provide a desired pore size between about 1 nanometer diameter and 50 nanometers diameter. Removal of the surfactant resulted in a mesoporous silica thin film on the substrate. Samples having a molecular weight below 1000, such as C.sub.60 and tryptophan, were adsorbed onto and into the mesoporous silica thin film sample holder and analyzed using laser desorption/ionization mass spectrometry.

  15. Enhancement of human immunodeficiency virus (HIV)-specific CD4+ and CD8+ cytotoxic T-lymphocyte activities in HIV-infected asymptomatic patients given recombinant gp160 vaccine.

    OpenAIRE

    Kundu, S K; Katzenstein, D; Moses, L E; Merigan, T C

    1992-01-01

    Twenty-six human immunodeficiency virus (HIV)-infected asymptomatic patients with CD4+ lymphocytes > 400 per mm3 were randomly allocated to a range of doses of recombinant gp160 or a control (recombinant hepatitis B vaccine) on a double-blind basis. Each patient received an injection at 0, 4, 12, 24, 36, and 48 weeks. Treatment assignments were decoded when all patients reached 28 weeks of the study period. HIV-1-specific CD4+ and CD8+ cytotoxic T lymphocyte (CTL) activities were assessed in ...

  16. Plasma-wall interactions data compendium-3. Hydrogen retention property, diffusion and recombination coefficients database for selected plasma-facing materials

    International Nuclear Information System (INIS)

    This report will present additional data to those included in the previous report of this series. These new data are ''effective'' hydrogen (deuterium) recombination coefficients estimated under the assumption that hydrogen recombination occurs in the bulk of materials, followed by immediate desorption to vacuum. The SI units are used for all the data collected in this report. (author)

  17. Mercury compounds characterization by thermal desorption

    OpenAIRE

    Rumayor Villamil, Marta; Díaz Somoano, Mercedes; López Antón, María Antonia; Martínez Tarazona, María Rosa

    2013-01-01

    [EN] The ability to accurately determine metal mercury content and identify different mercury species in solid samples is essential for developing remediation and control strategies. The aim of the present study is to characterize mercury compounds based on thermal desorption. For this purpose a series of samples was prepared and the operational parameters—heating velocity, carrier gas—were optimized. Fifteen commercial mercury compounds were analyzed for use as fingerprints. The results of t...

  18. Plutonium sorption and desorption behavior on bentonite.

    Science.gov (United States)

    Begg, James D; Zavarin, Mavrik; Tumey, Scott J; Kersting, Annie B

    2015-03-01

    Understanding plutonium (Pu) sorption to, and desorption from, mineral phases is key to understanding its subsurface transport. In this work we study Pu(IV) sorption to industrial grade FEBEX bentonite over the concentration range 10(-7)-10(-16) M to determine if sorption at typical environmental concentrations (≤10(-12) M) is the same as sorption at Pu concentrations used in most laboratory experiments (10(-7)-10(-11) M). Pu(IV) sorption was broadly linear over the 10(-7)-10(-16) M concentration range during the 120 d experimental period; however, it took up to 100 d to reach sorption equilibrium. At concentrations ≥10(-8) M, sorption was likely affected by additional Pu(IV) precipitation/polymerization reactions. The extent of sorption was similar to that previously reported for Pu(IV) sorption to SWy-1 Na-montmorillonite over a narrower range of Pu concentrations (10(-11)-10(-7) M). Sorption experiments with FEBEX bentonite and Pu(V) were also performed across a concentration range of 10(-11)-10(-7) M and over a 10 month period which allowed us to estimate the slow apparent rates of Pu(V) reduction on a smectite-rich clay. Finally, a flow cell experiment with Pu(IV) loaded on FEBEX bentonite demonstrated continued desorption of Pu over a 12 day flow period. Comparison with a desorption experiment performed with SWy-1 montmorillonite showed a strong similarity and suggested the importance of montorillonite phases in controlling Pu sorption/desorption reactions on FEBEX bentonite.

  19. Thermal desorption of ammonia from crystalline forsterite surfaces

    CERN Document Server

    Suhasaria, T; Zacharias, H

    2015-01-01

    The thermal desorption of ammonia (NH$_3$) from single crystal forsterite (010) has been investigated using temperature-programmed desorption. The effect of defects on the desorption process has been probed by the use of a rough cut forsterite surface prepared from the cleaved forsterite sample. Several approaches have been used to extract the desorption energy and pre-exponential factor describing the desorption kinetics. In the sub-monolayer coverage regime, the NH$_3$ desorption shows a broad distribution of desorption energies, indicating the presence of different adsorption sites, which results in an apparent coverage-dependent desorption energy. This distribution is sensitive to the surface roughness with the cut forsterite surface displaying a significantly broader distribution of desorption energies compared to the cleaved forsterite surface. The cut forsterite surface exhibits sites with desorption energies up to 62.5 kJ mol$^{-1} $ in comparison to a desorption energy of up to 58.0 kJ mol$^{-1} $ fo...

  20. Immunization with Dendritic Cells Pulsed ex vivo with Recombinant Chlamydial Protease-Like Activity Factor Induces Protective Immunity Against Genital Chlamydia muridarum Challenge

    Directory of Open Access Journals (Sweden)

    Bernard eArulanandam

    2011-12-01

    Full Text Available We have shown that immunization with soluble recombinant (r chlamydial protease-like activity factor (rCPAF and a T helper (Th 1 type adjuvant can induce significantly enhanced bacterial clearance and protection against Chlamydia–induced pathological sequelae in the genital tract. In this study, we investigated the use of bone marrow derived dendritic cells (BMDCs pulsed ex vivo with rCPAF+CpG in an adoptive subcutaneous immunization for the ability to induce protective immunity against genital chlamydial infection. We found that BMDCs pulsed with rCPAF+CpG efficiently up-regulated the expression of activation markers CD86, CD80, CD40 and major histocompatibility complex class II (MHC II, and secreted interleukin-12, but not IL-10 and IL-4. Mice adoptively immunized with rCPAF+CpG-pulsed BMDCs or UV-EB+CpG-pulsed BMDCs produced elevated levels of antigen-specific IFN- and enhanced IgG1 and IgG2a antibodies. Moreover, mice immunized with rCPAF+CpG-pulsed BMDCs or UV-EB+CpG-pulsed BMDCs exhibited significantly reduced genital Chlamydia shedding, accelerated resolution of infection, and reduced oviduct pathology when compared to infected mock-immunized animals. These results suggest that adoptive subcutaneous immunization with ex vivo rCPAF-pulsed BMDCs is an effective approach, comparable to that induced by UV-EB-BMDCs, for inducing robust anti-Chlamydia immunity.

  1. Lead sorption-desorption from organic residues.

    Science.gov (United States)

    Duarte Zaragoza, Victor M; Carrillo, Rogelio; Gutierrez Castorena, Carmen M

    2011-01-01

    Sorption and desorption are mechanisms involved in the reduction of metal mobility and bioavailability in organic materials. Metal release from substrates is controlled by desorption. The capacity of coffee husk and pulp residues, vermicompost and cow manure to adsorb Pb2+ was evaluated. The mechanisms involved in the sorption process were also studied. Organic materials retained high concentrations of lead (up to 36,000 mg L(-1)); however, the mechanisms of sorption varied according to the characteristics of each material: degree of decomposition, pH, cation exchange capacity and percentage of organic matter. Vermicompost and manure removed 98% of the Pb from solution. Lead precipitated in manure and vermicompost, forming lead oxide (PbO) and lead ferrite (PbFe4O7). Adsorption isotherms did not fit to the typical Freundlich and Langmuir equations. Not only specific and non-specific adsorption was observed, but also precipitation and coprecipitation. Lead desorption from vermicompost and cow manure was less than 2%. For remediation of Pb-polluted sites, the application of vermicompost and manure is recommended in places with alkaline soils because Pb precipitation can be induced, whereas coffee pulp residue is recommended for acidic soils where Pb is adsorbed.

  2. Thermal desorption of deuterium implanted into beryllium

    Energy Technology Data Exchange (ETDEWEB)

    Markin, A.V.; Chernikov, V.N.; Zakharov, A.P. [Institute of Physical Chemistry, Moscow (Russian Federation)] [and others

    1995-09-01

    By means of TDS measurements it is shown that the desorption of deuterium from Be implanted with 5 keV D ions to fluences, {Phi}, from 1x10{sup 20} D/m{sup 2} to 1x10{sup 21} D/m{sup 2} proceeds in one high temperature stage B, while at {Phi} {ge} 1.2x10{sup 21}D/m{sup 2} one more stage A is added. The desorption maximum A is narrow and consists of two peaks A{sub 1} and A{sub 2} at about 460 K and 490 K, respectively. Peak A{sub 1} is attributed to the desorption of deuterium from the walls of opened channels formed under D ion implantation. Peak {sub A}2 is a consequence of the opening of a part of closed bubbles/channels to the outer surface. The position of maximum B shifts noticeably and nonsteadily on the fluence in a range from 850 to 1050 K. The origin of this maximum is the liberation of D atoms bound at vacancy complexes discussed previously by Wampler. The dependence of Tm(B) on the fluence is governed by the interaction of freely migrating D atoms with partly opened or fully closed gas cavity arrangements which are created under temperature ramping, but differently in specimens implanted with D ions to different fluences.

  3. Light-induced atomic desorption: recent developments

    Science.gov (United States)

    Mariotti, E.; Atutov, S. N.; Biancalana, Valerio; Bocci, S.; Burchianti, A.; Marinelli, C.; Nasyrov, K. A.; Pieragnoli, B.; Moi, L.

    2001-04-01

    Light induced atomic desorption (LIAD) is an impressive manifestation of a new class of phenomena involving alkali atoms, dielectric films and light. LIAD consists of a huge emission of alkali atoms (experimentally proved for sodium, potassium, rubidium and cesium) from siloxane films when illuminated by laser or ordinary light. Most of the experiments have been performed in glass cells suitably coated by a thin film (of the order of 10 micrometer) either of poly - (dimethylsiloxane) (PDMS), a polymer, or of octamethylcyclotetrasiloxane (OCT), a crown molecule. LIAD is a combination of two processes: direct photo-desorption from the surface and diffusion within the siloxane layer. The photo-desorbed atoms are replaced by fresh atoms diffusing to the surface. Moreover, from the experimental data it comes out that the desorbing light increases atomic diffusion and hence the diffusion coefficient. To our knowledge this is the first time that such an effect is clearly observed, measured and discussed: LIAD represents a new class of photo-effects characterized by two simultaneous phenomena due to the light: surface desorption and fastened bulk diffusion.

  4. In vitro activity against Staphylococcus aureus of a novel antimicrobial agent, PRF-119, a recombinant chimeric bacteriophage endolysin.

    Science.gov (United States)

    Idelevich, Evgeny A; von Eiff, Christof; Friedrich, Alexander W; Iannelli, Domenico; Xia, Guoqing; Peters, Georg; Peschel, Andreas; Wanninger, Ingrid; Becker, Karsten

    2011-09-01

    Antistaphylococcal activity of the novel chimeric endolysin PRF-119 was evaluated with the microdilution method. The MIC(50) and MIC(90) of 398 methicillin-susceptible Staphylococcus aureus isolates were 0.098 μg/ml and 0.391 μg/ml, respectively (range, 0.024 to 0.780 μg/ml). Both the MIC(50) and MIC(90) values of 776 methicillin-resistant S. aureus isolates were 0.391 μg/ml (range, 0.024 to 1.563 μg/ml). All 192 clinical isolates of coagulase-negative staphylococci exhibited MIC values of >50 μg/ml. In conclusion, PRF-119 exhibited very good activity specifically against S. aureus.

  5. ADPase activity of recombinantly expressed thermotolerant ATPases may be caused by copurification of adenylate kinase of Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Baoyu; Sysoeva, Tatyana A.; Chowdhury, Saikat; Guo, Liang; Nixon, B.Tracy; (IIT); (Penn)

    2009-10-06

    Except for apyrases, ATPases generally target only the {gamma}-phosphate of a nucleotide. Some non-apyrase ATPases from thermophilic microorganisms are reported to hydrolyze ADP as well as ATP, which has been described as a novel property of the ATPases from extreme thermophiles. Here, we describe an apparent ADP hydrolysis by highly purified preparations of the AAA+ ATPase NtrC1 from an extremely thermophilic bacterium, Aquifex aeolicus. This activity is actually a combination of the activities of the ATPase and contaminating adenylate kinase (AK) from Escherichia coli, which is present at 1/10 000 of the level of the ATPase. AK catalyzes conversion of two molecules of ADP into AMP and ATP, the latter being a substrate for the ATPase. We raise concern that the observed thermotolerance of E. coli AK and its copurification with thermostable proteins by commonly used methods may confound studies of enzymes that specifically catalyze hydrolysis of nucleoside diphosphates or triphosphates. For example, contamination with E. coli AK may be responsible for reported ADPase activities of the ATPase chaperonins from Pyrococcus furiosus, Pyrococcus horikoshii, Methanococcus jannaschii and Thermoplasma acidophilum; the ATP/ADP-dependent DNA ligases from Aeropyrum pernix K1 and Staphylothermus marinus; or the reported ATP-dependent activities of ADP-dependent phosphofructokinase of P. furiosus. Purification methods developed to separate NtrC1 ATPase from AK also revealed two distinct forms of the ATPase. One is tightly bound to ADP or GDP and able to bind to Q but not S ion exchange matrixes. The other is nucleotide-free and binds to both Q and S ion exchange matrixes.

  6. Immune Response to Recombinant Capsid Proteins of Adenovirus in Humans: Antifiber and Anti-Penton Base Antibodies Have a Synergistic Effect on Neutralizing Activity

    Science.gov (United States)

    Gahéry-Ségard, Hanne; Farace, Françoise; Godfrin, Dominique; Gaston, Jesintha; Lengagne, Renée; Tursz, Thomas; Boulanger, Pierre; Guillet, Jean-Gérard

    1998-01-01

    Replication-deficient adenovirus used in humans for gene therapy induces a strong immune response to the vector, resulting in transient recombinant protein expression and the blocking of gene transfer upon a second administration. Therefore, in this study we examined in detail the capsid-specific humoral immune response in sera of patients with lung cancer who had been given one dose of a replication-defective adenovirus. We analyzed the immune response to the three major components of the viral capsid, hexon (Hx), penton base (Pb), and fiber (Fi). A longitudinal study of the humoral response assayed on adenovirus particle-coated enzyme-linked immunosorbent assay plates showed that patients had preexisting immunity to adenovirus prior to the administration of adenovirus–β-gal. The level of the response increased in three patients after adenovirus administration and remained at a maximum after three months. One patient had a strong immune response to adenovirus prior to treatment, and this response was unaffected by adenovirus administration. Sera collected from the patients were assayed for recognition of each individual viral capsid protein to determine more precisely the molecular basis of the humoral immune response. Clear differences existed in the humoral response to the three major components of the viral capsid in serum from humans. Sequential appearance of these antibodies was observed: anti-Fi antibodies appeared first, followed by anti-Pb antibodies and then by anti-Hx antibodies. Moreover, anti-Fi antibodies preferentially recognized the native trimeric form of Fi protein, suggesting that they recognized conformational epitopes. Our results showed that sera with no neutralizing activity contained only anti-Fi antibodies. In contrast, neutralizing activity was only obtained with sera containing anti-Fi and anti-Pb antibodies. More importantly, we showed that anti-native Fi and anti-Pb antibodies had a synergistic effect on neutralization. The

  7. Comparison of recombination models in organic bulk heterojunction solar cells

    International Nuclear Information System (INIS)

    Recombination in bulk-heterojunction (BHJ) organic solar cells is the key loss mechanism, and it directly affects characteristic parameters such as power conversion efficiency, short-circuit current, open-circuit voltage, and fill factor. However, which recombination mechanism dominates the loss in organic materials is unclear at present. In this work, we simulate state-of-art BHJ solar cells using five recombination models, including direct recombination, Langevin recombination, charge transfer state recombination, trap-assisted recombination, and recombination via tail. All processes are strongly dependent on charge carrier mobility and exhibit a similar recombination distribution in active layer. For high mobilities, all models present a similar behavior along with the increased mobilities, whereas, there are slight differences in open-circuit voltage between trap/tail model and other ones at lower mobilities, resulting from the interaction between photo-carriers and dark-carriers

  8. Recombinant microorganisms for increased production of organic acids

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Jian; Kleff, Susanne; Guettler, Michael V

    2013-04-30

    Disclosed are recombinant microorganisms for producing organic acids. The recombinant microorganisms express a polypeptide that has the enzymatic activity of an enzyme that is utilized in the pentose phosphate cycle. The recombinant microorganism may include recombinant Actinobacillus succinogenes that has been transformed to express a Zwischenferment (Zwf) gene. The recombinant microorganisms may be useful in fermentation processes for producing organic acids such as succinic acid and lactic acid. Also disclosed are novel plasmids that are useful for transforming microorganisms to produce recombinant microorganisms that express enzymes such as Zwf.

  9. A Novel Cold-Active Lipase from Candida albicans: Cloning, Expression and Characterization of the Recombinant Enzyme

    OpenAIRE

    Dong-Ming Lan; Yong-Hua Wang; Bo Yang; Ning Yang; Wen-Kai Wang; Yan-Fei Shen

    2011-01-01

    A novel lipase gene lip5 from the yeast Candida albicans was cloned and sequenced. Alignment of amino acid sequences revealed that 86–34% identity exists with lipases from other Candida species. The lipase and its mutants were expressed in the yeast Pichia pastoris, where alternative codon usage caused the mistranslation of 154-Ser and 293-Ser as leucine. 154-Ser to leucine resulted in loss of expression of Lip5, and 293-Ser to leucine caused a marked reduction in the lipase activity. Lip5-DM...

  10. WATER ADSORPTION AND DESORPTION ISOTHERMS ON MILK POWDER: II. WHOLE MILK

    Directory of Open Access Journals (Sweden)

    Edgar M. Soteras

    2014-03-01

    Full Text Available The aim of this research was the determination of adsorption and desorption isotherms of cow whole milk powder. The experiments have been carried out at 15, 25 and 40 ºC, in ranges of moisture and water activity characteristic of normal conditions in which the processes of drying, packaging and storage are developed. By studying the influence of the temperature on the experimental plots, the isosteric adsorption heat was determined. Experimental data were correlated to the referential model of Guggenheim, Anderson and Boer (GAB. For both, adsorption and desorption, a good model fit was observed. The isotherms showed very similar shapes between them and, by comparing adsorption and desorption isotherms, the phenomenon of hysteresis was confirmed.

  11. Photoionization and Recombination

    Science.gov (United States)

    Nahar, Sultana N.

    2000-01-01

    Theoretically self-consistent calculations for photoionization and (e + ion) recombination are described. The same eigenfunction expansion for the ion is employed in coupled channel calculations for both processes, thus ensuring consistency between cross sections and rates. The theoretical treatment of (e + ion) recombination subsumes both the non-resonant recombination ("radiative recombination"), and the resonant recombination ("di-electronic recombination") processes in a unified scheme. In addition to the total, unified recombination rates, level-specific recombination rates and photoionization cross sections are obtained for a large number of atomic levels. Both relativistic Breit-Pauli, and non-relativistic LS coupling, calculations are carried out in the close coupling approximation using the R-matrix method. Although the calculations are computationally intensive, they yield nearly all photoionization and recombination parameters needed for astrophysical photoionization models with higher precision than hitherto possible, estimated at about 10-20% from comparison with experimentally available data (including experimentally derived DR rates). Results are electronically available for over 40 atoms and ions. Photoionization and recombination of He-, and Li-like C and Fe are described for X-ray modeling. The unified method yields total and complete (e+ion) recombination rate coefficients, that can not otherwise be obtained theoretically or experimentally.

  12. Pyridoxine Supplementation Improves the Activity of Recombinant Glutamate Decarboxylase and the Enzymatic Production of Gama-Aminobutyric Acid.

    Directory of Open Access Journals (Sweden)

    Yan Huang

    Full Text Available Glutamate decarboxylase (GAD catalyzes the irreversible decarboxylation of L-glutamate to the valuable food supplement γ-aminobutyric acid (GABA. In this study, GAD from Escherichia coli K12, a pyridoxal phosphate (PLP-dependent enzyme, was overexpressed in E. coli. The GAD produced in media supplemented with 0.05 mM soluble vitamin B6 analog pyridoxine hydrochloride (GAD-V activity was 154.8 U mL-1, 1.8-fold higher than that of GAD obtained without supplementation (GAD-C. Purified GAD-V exhibited increased activity (193.4 U mg-1, 1.5-fold higher than that of GAD-C, superior thermostability (2.8-fold greater than that of GAD-C, and higher kcat/Km (1.6-fold higher than that of GAD-C. Under optimal conditions in reactions mixtures lacking added PLP, crude GAD-V converted 500 g L-1 monosodium glutamate (MSG to GABA with a yield of 100%, and 750 g L-1 MSG with a yield of 88.7%. These results establish the utility of pyridoxine supplementation and lay the foundation for large-scale enzymatic production of GABA.

  13. Pyridoxine Supplementation Improves the Activity of Recombinant Glutamate Decarboxylase and the Enzymatic Production of Gama-Aminobutyric Acid.

    Science.gov (United States)

    Huang, Yan; Su, Lingqia; Wu, Jing

    2016-01-01

    Glutamate decarboxylase (GAD) catalyzes the irreversible decarboxylation of L-glutamate to the valuable food supplement γ-aminobutyric acid (GABA). In this study, GAD from Escherichia coli K12, a pyridoxal phosphate (PLP)-dependent enzyme, was overexpressed in E. coli. The GAD produced in media supplemented with 0.05 mM soluble vitamin B6 analog pyridoxine hydrochloride (GAD-V) activity was 154.8 U mL-1, 1.8-fold higher than that of GAD obtained without supplementation (GAD-C). Purified GAD-V exhibited increased activity (193.4 U mg-1, 1.5-fold higher than that of GAD-C), superior thermostability (2.8-fold greater than that of GAD-C), and higher kcat/Km (1.6-fold higher than that of GAD-C). Under optimal conditions in reactions mixtures lacking added PLP, crude GAD-V converted 500 g L-1 monosodium glutamate (MSG) to GABA with a yield of 100%, and 750 g L-1 MSG with a yield of 88.7%. These results establish the utility of pyridoxine supplementation and lay the foundation for large-scale enzymatic production of GABA. PMID:27438707

  14. Pyridoxine Supplementation Improves the Activity of Recombinant Glutamate Decarboxylase and the Enzymatic Production of Gama-Aminobutyric Acid

    Science.gov (United States)

    Huang, Yan; Su, Lingqia; Wu, Jing

    2016-01-01

    Glutamate decarboxylase (GAD) catalyzes the irreversible decarboxylation of L-glutamate to the valuable food supplement γ-aminobutyric acid (GABA). In this study, GAD from Escherichia coli K12, a pyridoxal phosphate (PLP)-dependent enzyme, was overexpressed in E. coli. The GAD produced in media supplemented with 0.05 mM soluble vitamin B6 analog pyridoxine hydrochloride (GAD-V) activity was 154.8 U mL-1, 1.8-fold higher than that of GAD obtained without supplementation (GAD-C). Purified GAD-V exhibited increased activity (193.4 U mg-1, 1.5-fold higher than that of GAD-C), superior thermostability (2.8-fold greater than that of GAD-C), and higher kcat/Km (1.6-fold higher than that of GAD-C). Under optimal conditions in reactions mixtures lacking added PLP, crude GAD-V converted 500 g L-1 monosodium glutamate (MSG) to GABA with a yield of 100%, and 750 g L-1 MSG with a yield of 88.7%. These results establish the utility of pyridoxine supplementation and lay the foundation for large-scale enzymatic production of GABA. PMID:27438707

  15. Solvent-induced desorption of alkanethiol ligands from Au nanoparticles.

    Science.gov (United States)

    Huang, Yuanyuan; Liu, Wei; Cheng, Hao; Yao, Tao; Yang, Lina; Bao, Jie; Huang, Ting; Sun, Zhihu; Jiang, Yong; Wei, Shiqiang

    2016-06-21

    Removing surfactants from a colloidal metal nanoparticle surface is necessary for their realistic applications, and how they could be stripped is a subject of active investigation. Here, we report a solvent-induced desorption of dodecanethiol ligands from the gold nanoparticle surface, and traced this desorption process using a combination of in situ X-ray absorption fine structure (XAFS) and Raman spectroscopic techniques. In situ analysis results reveal that the solvent exchange of ethanol with tetrahydrofuran (THF) can effectively remove dodecanethiol ligands while keeping the particle morphology unchanged. Upon increasing the THF/ethanol ratio from 0 : 1 to 5 : 1, the surface coverage of thiol on the Au surface is reduced from 0.47 to 0.07, suggesting the depletion of ligands first from the nanoparticle facet sites, then from the edge sites, while the ligands at the corner sites are intact. This work enriches our knowledge on surfactant removal and may pave the way towards preparing surface-clean nanoparticles for practical applications. PMID:27241025

  16. Overproduction and biological activity of prodigiosin-like pigments from recombinant fusant of endophytic marine Streptomyces species.

    Science.gov (United States)

    El-Bondkly, Ahmed M A; El-Gendy, Mervat M A; Bassyouni, Rasha H

    2012-11-01

    Thirty-four endophytic marine Actinomycetes isolates were recovered from the Egyptian marine sponge Latrunculia corticata, out of them 5 isolates (14.7 %) showed red single colonies on yeast-CzAPEK plates. Isolates under the isolation code NRC50 and NRC51 were observed with the strongest red biomass. After application of protoplast fusion between NRC50 and NRC51 isolates, 26 fusants were selected and produced widely different amounts of prodigiosin-like pigments (PLPs) on different fermentation media. Among them fusant NRCF69 produced 79 and 160.4 % PLPs more than parental strains NRC50 and NRC51, respectively. According to the analysis of 16S rDNA sequence (amplified, sequenced, and submitted to GenBank under Accession no. JN232405 and JN232406, respectively), together with their morphological and biochemical characteristics, parental strains NRC50 (P1) and NRC51 (P2) were identified as Streptomyces sp. and designated as Streptomyces sp. NRC50 and Streptomyces sp. NRC51. This study describes a low cost, effective production media by using peanut seed broth, sunflower oil broth or dairy processing wastewater broth alone, or supplemented with 0.5 % mannitol that supports the production of PLPs by the Streptomyces fusant NRCF69 under study (42.03, 40.11, 36.7 and 47 g L(-1), respectively). PLPs compounds exhibited significant cytotoxic activities against three human cancer cell lines: colon cancer cell line (HCT-116), liver cancer cell line (HEPG-2) and breast cancer cell line (MCF-7) and antimycotic activity against clinical dermatophyte isolates of Trichophyton, Microsporum and Epidermophyton.

  17. Rice endosperm is cost-effective for the production of recombinant griffithsin with potent activity against HIV.

    Science.gov (United States)

    Vamvaka, Evangelia; Arcalis, Elsa; Ramessar, Koreen; Evans, Abbey; O'Keefe, Barry R; Shattock, Robin J; Medina, Vicente; Stöger, Eva; Christou, Paul; Capell, Teresa

    2016-06-01

    Protein microbicides containing neutralizing antibodies and antiviral lectins may help to reduce the rate of infection with human immunodeficiency virus (HIV) if it is possible to manufacture the components in large quantities at a cost affordable in HIV-endemic regions such as sub-Saharan Africa. We expressed the antiviral lectin griffithsin (GRFT), which shows potent neutralizing activity against HIV, in the endosperm of transgenic rice plants (Oryza sativa), to determine whether rice can be used to produce inexpensive GRFT as a microbicide ingredient. The yield of (OS) GRFT in the best-performing plants was 223 μg/g dry seed weight. We also established a one-step purification protocol, achieving a recovery of 74% and a purity of 80%, which potentially could be developed into a larger-scale process to facilitate inexpensive downstream processing. (OS) GRFT bound to HIV glycans with similar efficiency to GRFT produced in Escherichia coli. Whole-cell assays using purified (OS) GRFT and infectivity assays using crude extracts of transgenic rice endosperm confirmed that both crude and pure (OS) GRFT showed potent activity against HIV and the crude extracts were not toxic towards human cell lines, suggesting they could be administered as a microbicide with only minimal processing. A freedom-to-operate analysis confirmed that GRFT produced in rice is suitable for commercial development, and an economic evaluation suggested that 1.8 kg/ha of pure GRFT could be produced from rice seeds. Our data therefore indicate that rice could be developed as an inexpensive production platform for GRFT as a microbicide component. PMID:26800650

  18. Recombineering Homologous Recombination Constructs in Drosophila

    OpenAIRE

    Carreira-Rosario, Arnaldo; Scoggin, Shane; Shalaby, Nevine A.; Williams, Nathan David; Hiesinger, P. Robin; Buszczak, Michael

    2013-01-01

    The continued development of techniques for fast, large-scale manipulation of endogenous gene loci will broaden the use of Drosophila melanogaster as a genetic model organism for human-disease related research. Recent years have seen technical advancements like homologous recombination and recombineering. However, generating unequivocal null mutations or tagging endogenous proteins remains a substantial effort for most genes. Here, we describe and demonstrate techniques for using recombineeri...

  19. In vivo distribution of recombinant interleukin-2-activated autologous lymphocytes administered by intra-arterial infusion in patients with renal cell carcinoma

    International Nuclear Information System (INIS)

    Recombinant interleukin-2 (RIL 2)-activated autologous peripheral blood lymphocytes (PBL) were infused directly into the renal arteries of 3 patients with renal cell carcinoma, and the in vivo distribution of the infused cells was investigated. In vitro studies to define the optimal culture conditions indicated that maximal lymphokine-activated killer activity was observed at around 10-20 days in culture, as judged by the cytotoxicity against fresh allogenic tumor cells. Maximal expression of the interleukin-2 receptor was also obtained at around 10 days. PBL collected by leukopheresis from each patient were thus cultured for 10 days with RIL 2, labeled with 111In-oxine, and then infused directly into the renal artery of the affected kidney via a catheter. Radioactivity in the infused side of the kidneys increased immediately after the infusion but then gradually decreased. Radioactivity in the lungs also rapidly increased within the first hour but then cleared gradually, whereas that in the liver and spleen tended to increase steadily. Nevertheless, at 48 hours, the infused side of the kidneys retained levels of radioactivity comparable to those seen in the liver and spleen, while the levels seen in the lungs were already close to background levels. The radioactivity in the areas corresponding to tumors remained consistently higher than that in the normal parts of the affected kidneys. The direct comparison of the radioactivity distribution pattern with the macroscopic appearance of surgically resected kidneys indicated that the accumulation of radioactivity was indeed selectively associated with the tumor tissues in the kidneys, except for a case in which the tumor was quite necrotic and hypovascular

  20. Bioassay of Estrogenic Activity of Effluent and Influent in a Farm Wastewater Treatment Plant Using an in vitro Recombinant Assay with Yeast Cells

    Institute of Scientific and Technical Information of China (English)

    XIANG-MING LI; FANG-NI LUO; GuI-XIA LIU; PING-TING ZHU

    2008-01-01

    Objective Environmental estrogens at an elevated concentration are known to produce adverse effects on human and animal life. However, the majority of researches have been focused on ndustrial discharges, while the impact of livestock wastes as a source of endocrine disrupters in aquatic environments has been rarely elucidated. In order to investigate the contribution of environmental estrogens from livestock, the estrogenic activity in water samples from a farm wastewater treatment plant was analyzed by a recombinant yeast screening method. Methods The extracts prepared from 15 selected water samples from the farm wastewater treatment plant, among which 6 samples were from pre-treatment section (influents) and 9 from post-treatment section (effluents), were analyzed for estrogenic activity by cellar bioassay. Yeast cells transfected with the expression plasmid of human estrogen receptor and the Lac Z reporter plasmid encoding β-galactossidase, were used to measure the estrogen-like compounds in the farm wastewater treatment plant. Results The wastewater samples from influents showed a higher estrogenic potency than the effluent samples showing a low induction of β-galactossidase relative to solvent control condition. By comparison with a standard curve for 1713-estradiol (E2), estrogenic potency in water samples from the influents was calculated as E2-equivalent and ranged from 0.1 to 150 pM E2-equivalent. The estrogenic potency in water samples from the effluents was significantly lower than that in the influents, and 7 water samples had less detectable limit in the total of 9 samples. Conclusion Yeast bioassay of estrogenic activity in most of the samples from the farm wastewater after disposal by traditional sewage treatment showed negative results.

  1. Direct pathway for sticking/desorption of H2 on Si(100)

    DEFF Research Database (Denmark)

    Kratzer, Peter; Hammer, Bjørk; Nørskov, Jens Kehlet

    1995-01-01

    The energetics of H2 interacting with the Si(100) surface is studied by means of ab initio total-energy calculations within the framework of density-functional theory. We find a direct desorption pathway from the monohydride phase that is compatible with experimental activation energies and...

  2. Current-Driven Hydrogen Desorption from Graphene: Experiment and Theory

    Energy Technology Data Exchange (ETDEWEB)

    Gao, L.; Pal, Partha P.; Seideman, Tamar; Guisinger, Nathan P.; Guest, Jeffrey R.

    2016-02-04

    Electron-stimulated desorption of hydrogen from the graphene/SiC(0001) surface at room temperature was investigated with ultrahigh vacuum scanning tunneling microscopy and ab initio calculations in order to elucidate the desorption mechanisms and pathways. Two different desorption processes were observed. In the high electron energy regime (4-8 eV), the desorption yield is independent of both voltage and current, which is attributed to the direct electronic excitation of the C-H bond. In the low electron energy regime (2-4 eV), however, the desorption yield exhibits a threshold dependence on voltage, which is explained by the vibrational excitation of the C-H bond via transient ionization induced by inelastic tunneling electrons. The observed current-independence of the desorption yield suggests that the vibrational excitation is a singleelectron process. We also observed that the curvature of graphene dramatically affects hydrogen desorption. Desorption from concave regions was measured to be much more probable than desorption from convex regions in the low electron energy regime (~ 2 eV), as would be expected from the identified desorption mechanism

  3. Safety and efficacy of recombinant activated factor VII: a randomized placebo-controlled trial in the setting of bleeding after cardiac surgery

    DEFF Research Database (Denmark)

    Gill, Ravi; Herbertson, Mike; Vuylsteke, Alain;

    2009-01-01

    BACKGROUND: Blood loss is a common complication of cardiac surgery. Evidence suggests that recombinant activated factor VII (rFVIIa) can decrease intractable bleeding in patients after cardiac surgery. Our objective was to investigate the safety and possible benefits of rFVIIa in patients who bleed...... after cardiac surgery. METHODS AND RESULTS: In this phase II dose-escalation study, patients who had undergone cardiac surgery and were bleeding were randomized to receive placebo (n=68), 40 microg/kg rFVIIa (n=35), or 80 microg/kg rFVIIa (n=69). The primary end points were the number of patients....../kg, 14%; P=0.25; 80 microg/kg, 12%; P=0.43). After randomization, significantly fewer patients in the rFVIIa group underwent a reoperation as a result of bleeding (P=0.03) or required allogeneic transfusions (P=0.01). CONCLUSIONS: On the basis of this preliminary evidence, rFVIIa may be beneficial for...

  4. 具有溶栓活性的重组乳酸乳球菌的构建%Construction of recombinant Lactococcus lactis with fibrinolytic activity

    Institute of Scientific and Technical Information of China (English)

    余凤云; 冯浩; 许芳; 闫达中

    2011-01-01

    Pro-nattokinase gene was amplified by PCR from Bacillus subtilis subsp.natto genomic DNA, which was cloned into pGT-19 vector and then sequenced.The recombinant plasmid pFY002 was constructed by inserting pro-nattokinase gene into expression vector pNZ8048 and was transformed into Lactococcus lactis NZ9000.The fibrinolytic activity was analyzed after the expression of gene was induced by nisin A.The optimum conditions including nisinA concentration, temperature and induction time in the engineering L.lactis were further investigated.%利用PCR方法从纳豆芽孢杆菌(Bacillus subtilis subsp.natto)基因组DNA中扩增纳豆激酶原基因,构建了纳豆激酶原基因的表达载体pFY002,转化LactococcuslactisNZ9000,得到活性表达纳豆激酶的重组菌LactococcuslactisNZ9000/pFY002.利用纤维蛋白平板法检测其溶栓活性,并对诱导剂乳链菌肽(NisinA)的浓度、温度、诱导时间对重组菌产酶的影响进行探究.

  5. Guidelines for the intravenous application of recombinant tissue-type plasminogen activator (alteplase), the second edition, October 2012: a guideline from the Japan Stroke Society.

    Science.gov (United States)

    Minematsu, Kazuo; Toyoda, Kazunori; Hirano, Teruyuki; Kimura, Kazumi; Kondo, Rei; Mori, Etsuro; Nakagawara, Jyoji; Sakai, Nobuyuki; Shiokawa, Yoshiaki; Tanahashi, Norio; Yasaka, Masahiro; Katayama, Yasuo; Miyamoto, Susumu; Ogawa, Akira; Sasaki, Makoto; Suga, Sadao; Yamaguchi, Takenori

    2013-07-01

    In Japan, intravenous alteplase, a recombinant tissue-type plasminogen activator (rt-PA), was approved for an indication of ischemic stroke in 2005 on the basis of the results of a clinical trial with a unique dose of the drug (0.6 mg/kg). The Japan Stroke Society published the guidelines for intravenous application of rt-PA and organized training sessions for proper use all over Japan in an effort to promote the safe, widespread use of intravenous alteplase. Seven years following its approval, clinical experience with intravenous alteplase has accumulated, additional evidence of intravenous alteplase has been found in Japan and overseas, and the medical environment has substantially changed, including approvals for new drugs and medical devices. Notably, the use of alteplase in the extended therapeutic time window (within 4.5 hours of symptom onset) became covered by insurance in Japan in August 2012. To address these changing situations, we have decided to prepare the revised guidelines. In preparing the second edition, we took care to make its contents more practical by emphasizing information needed in clinical practice. While the first edition was developed with emphasis on safety in light of limited clinical experience with intravenous alteplase in Japan in 2005, this second edition is a substantial revision of the first edition mainly in terms of eligibility criteria, on the basis of accumulated evidence and the clinical experience.

  6. A Shark Liver Gene-Derived Active Peptide Expressed in the Silkworm, Bombyx mori: Preliminary Studies for Oral Administration of the Recombinant Protein

    Directory of Open Access Journals (Sweden)

    Jun Li

    2013-05-01

    Full Text Available Active peptide from shark liver (APSL is a cytokine from Chiloscyllium plagiosum that can stimulate liver regeneration and protects the pancreas. To study the effect of orally administered recombinant APSL (rAPSL on an animal model of type 2 diabetes mellitus, the APSL gene was cloned, and APSL was expressed in Bombyx mori N cells (BmN cells, silkworm larvae and silkworm pupae using the silkworm baculovirus expression vector system (BEVS. It was demonstrated that rAPSL was able to significantly reduce the blood glucose level in mice with type 2 diabetes induced by streptozotocin. The analysis of paraffin sections of mouse pancreatic tissues revealed that rAPSL could effectively protect mouse islets from streptozotocin-induced lesions. Compared with the powder prepared from normal silkworm pupae, the powder prepared from pupae expressing rAPSL exhibited greater protective effects, and these results suggest that rAPSL has potential uses as an oral drug for the treatment of diabetes mellitus in the future.

  7. Antitumor activity of recombinant Bacille Calmette-Guérin secreting interleukin-15-Ag85B fusion protein against bladder cancer.

    Science.gov (United States)

    Takeuchi, Ario; Eto, Masatoshi; Tatsugami, Katsunori; Shiota, Masaki; Yamada, Hisakata; Kamiryo, Yoriyuki; Dejima, Takashi; Kashiwagi, Eiji; Kiyoshima, Keijiro; Inokuchi, Junichi; Takahashi, Ryosuke; Yokomizo, Akira; Ohara, Naoya; Yoshikai, Yasunobu

    2016-06-01

    Mycobacterium bovis Bacillus Calmette-Guérin (BCG) is used for the treatment of bladder cancer. The recruitment of neutrophlis to the bladder after BCG instillation exerts anti-tumor activity against bladder tumor. We have recently demonstrated that interleukin (IL)-17A produced by γδ T cells played a role in the recruitment of neutrophlis to the bladder after BCG instillation. IL-15 is known to play an important role in neutrophil migration during inflammation. We previously constructed a recombinant BCG strain expressing the fusion protein of IL-15 and Ag85B (BCG-IL-15) for prevention of Mycobacterium tuberculosis infection. Here we compared the efficacy of the BCG-IL-15 in protection against bladder cancer with that of rBCG-Ag85B (BCG). Six-week-old female C57BL/6 mice were inoculated with MB49 bladder tumor cells in the bladder and subsequently intravesically inoculated with BCG or BCG-IL-15. BCG-IL-15 treatment significantly prolonged survival of mice inoculated with bladder cancer cells compared with BCG treatment. Infiltration of neutrophils was significantly elevated in BCGB-IL-15 treated mice accompanied by increased chemokines (MIP-2 and MIP-1α) in the bladder. Thus, BCG-IL-15 exerted additive effect on Infiltration of neutrophils in the bladder. BCG-IL-15 may be a promising drug for non-muscle invasive bladder cancer. PMID:27093372

  8. A massive transfusion protocol incorporating a higher FFP/RBC ratio is associated with decreased use of recombinant activated factor VII in trauma patients.

    Science.gov (United States)

    Tan, Josenia N M; Burke, Peter A; Agarwal, Suresh K; Mantilla-Rey, Nelson; Quillen, Karen

    2012-04-01

    We implemented a protocol incorporating a higher fresh frozen plasma (FFP)/RBC ratio for the management of trauma patients requiring massive transfusion in 2007. This study aims to identify issues that affected the effective deployment of the massive transfusion protocol (MTP) and compare outcome variables with a historic cohort. Data from 49 trauma patients who received at least 10 units of packed RBCs within 24 hours were analyzed and compared with a historic massively transfused cohort who had received recombinant activated factor VII (rFVIIa). Of the patients, 28 received an FFP/RBC ratio of 1:1 to 1:2; 12 received a lower ratio of 1:2 to 1:4; 3 received more than 1:1 and 6 had less than 1:4. Compared with the historic cohort, the 1:1-1:2 group received significantly fewer blood components and did not require rescue rFVIIa. An MTP incorporating a higher FFP/RBC ratio of 1:1 to 1:2 is associated with decreased use of blood components and may obviate the need for rFVII.

  9. Regulation of homologous recombination at telomeres in budding yeast

    DEFF Research Database (Denmark)

    Eckert-Boulet, Nadine; Lisby, Michael

    2010-01-01

    Homologous recombination is suppressed at normal length telomere sequences. In contrast, telomere recombination is allowed when telomeres erode in the absence of telomerase activity or as a consequence of nucleolytic degradation or incomplete replication. Here, we review the mechanisms...... that contribute to regulating mitotic homologous recombination at telomeres and the role of these mechanisms in signalling short telomeres in the budding yeast Saccharomyces cerevisiae....

  10. Identification, cloning and lactonase activity of recombinant protein of N-acyl homoserine lactonase (AiiA from Bacillus thuringiensis 147-115-16 strain.

    Directory of Open Access Journals (Sweden)

    Alvaro Mauricio Florez Escobar

    2014-06-01

    Full Text Available Título en español: Identificación, clonación y actividad lactonasa de la proteína recombinante de N-ácil homoserina lactonasa (AiiA de Bacillus thuringiensis cepa 147-115-16 Short title: N-acyl homoserine lactonase (AiiA from Bacillus thuringiensis Abstract: The quorum-quenching N-acyl homoserine lactonases are a family of bacterial metalloenzymes that participate in degradation of N-acyl homoserine lactones (AHLs, disrupting the quorum sensing system of gram negative bacterial species. From a collection of Bacillus thuringiensis strains isolated in Colombia from plants and exhibiting toxic activity against lepidopteran insects, 310 bacterial isolates were tested to determine lactonase activity by using biosensor systems in presence of synthetic N-hexanoyl-L-homoserine lactone (C6-HSL and N-octanoyl-L-homoserine lactone (C8-HSL. From them, 251 strains showed degrading activity to both C6-HSL and C8-HSL, 57% exhibited degrading activity to C6-HSL and 43% to C8-HSL. One B. thuringiensis strain, denoted as 147-115-16, that exhibit high degrading activity to C6-HSL and C8-HSL, was able to attenuate soft rot symptoms in infected potato slices with Pectobacterium carotovorum. This strain contains an homologous of the aiiA gene that was cloned, sequenced and expressed in Esherichia coli DE3. The recombinant protein AiiA147-11516 displays activity to C6-HSL, C8-HSL, N-(β-ketocaproyl (3-O-C6-HSL and N-3-oxo-dodecanoyl (3-O-C12-HSL. The recombinant strain in the presence of P. caratovorum cultures was able to attenuate the infection, suggesting that it interferes either with the accumulation or with the response to the AHLs signals. Acording to this data and based on previous report from recombinant AiiA147-11516, this enzyme exhibits activity to a wide range of catalytic substrates suggesting its industrial application in the disease control programs through plants transformation.Key words: lactones, Quorum sensing, Quorum quenching, Lactonases

  11. CONSTRUCTION OF ACTIVE RECOMBINANT CASPASE-3 EUKARYOTIC EXPRESSION PLA SMID AND EFFECT OF r-CASPASE-3 ON APOPTOSIS OF PANCREATIC CARCINOMA CELLS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To construct active recombinant cas pa ses-3 gene(r-caspases-3)eukaryotic expression plasmid and observe the apoptos is inducing activity of r-caspase-3 in pancreatic carcinoma cells. Methods pcDNA3.1(+)/r-caspase-3 was constructed and pan creatic carcinoma cells(PC-Ⅱ)were transfected with the pcDNA3.1(+)/r-caspases -3 by liposomes(LipofectAMINE).The expression of r-Caspase-3 mRNA in pancreat ic carcinoma cells was detected by reverse transcription process of the polymera se chain reaction(RT-PCR), and the signs of apoptosis were examined in pancreat ic carcinoma cells by the methods of the DNA electrophoresis and flow cytometry analysis(FACS).Results The sequence inserted in pBlueSKM/r-Caspase-3 p lasmid was coincident with that of the r-caspases-3. The evaluation result of pcDNA3.1(+)/r-caspases-3 through enzyme cutting was correct. A 894bp strap was observed by RT-PCR after pancreatic carcinoma cells being transfected with the pcDNA3.1(+)/r-caspases-3 by liposomes. No strap was found in control groups. A characteristic DNA ladder was observed in pancreatic carcinoma cells DNA elect r ophoresis, and transparent hypodiploid karyotype peak was found by FACS. Conclusion The plasmid of pcDNA3.1(+)/r-Caspase-3 was c onstructed successfully, the expression of r-Caspase-3 mRMA in pancreatic carc inoma cells was confirmed by RT-PCR, and pcDNA3.1(+)/r-Caspase-3 can induce a poptosis in pancreatic carcinoma cells.

  12. An Approach to Breast Cancer Immunotherapy: The Apoptotic Activity of Recombinant Anti-Interleukin-6 Monoclonal Antibodies in Intact Tumour Microenvironment of Breast Carcinoma.

    Science.gov (United States)

    Abou-Shousha, S; Moaaz, M; Sheta, M; Motawea, M A

    2016-06-01

    Current work is one of our comprehensive preclinical studies, a new approach to breast cancer (BC) immunotherapy through induction of tumour cell apoptosis. Tumour growth is not just a result of uncontrolled cell proliferation but also of reduced apoptosis. High levels of interleukin-6 (IL-6) are associated with metastatic BC and correlated with poor survival as it promotes growth of tumour-initiating cells during early tumorigenesis protecting these cells from apoptosis. Therefore, this study aims at investigating the potential of anti-IL-6 monoclonal antibodies to suppress IL-6 proliferative/anti-apoptotic activities in intact tumour microenvironment of BC. Fresh sterile tumour and normal breast tissue specimens were taken from 50 female Egyptian patients with BC undergoing radical mastectomy. A unique tissue culture system designed to provide cells of each intact tumour/normal tissue sample with its proper microenvironment either supplemented or not with anti-IL-6 monoclonal antibodies. To evaluate the apoptotic activity of anti-IL-6 as a novel candidate for BC treatment strategy, we compared its effects with those obtained using tumour necrosis-related apoptosis-inducing ligand TRAIL as an established apoptotic agent. Our results revealed that levels of either anti-IL-6- or TRAIL-induced apoptosis in the tumour or normal tissue cultures were significantly higher than those in their corresponding untreated ones (P Recombinant anti-IL-6 monoclonal antibodies could represent a novel effective element of immunotherapeutic treatment strategy for BC. The selectivity and anti-apoptotic potential of anti-IL-6 is highly hopeful in IL-6- abundant BC tumour microenvironment. PMID:26971879

  13. Recombinant Tissue Plasminogen Activator Induces Neurological Side Effects Independent on Thrombolysis in Mechanical Animal Models of Focal Cerebral Infarction: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Wei, You-Dong; Liu, Yi-Yun; Ren, Yi-Fei; Liang, Zi-Hong; Wang, Hai-Yang; Zhao, Li-Bo; Xie, Peng

    2016-01-01

    Background and Purpose Recombinant tissue plasminogen activator (rtPA) is the only effective drug approved by US FDA to treat ischemic stroke, and it contains pleiotropic effects besides thrombolysis. We performed a meta-analysis to clarify effect of tissue plasminogen activator (tPA) on cerebral infarction besides its thrombolysis property in mechanical animal stroke. Methods Relevant studies were identified by two reviewers after searching online databases, including Pubmed, Embase, and ScienceDirect, from 1979 to 2016. We identified 6, 65, 17, 12, 16, 12 and 13 comparisons reporting effect of endogenous tPA on infarction volume and effects of rtPA on infarction volume, blood-brain barrier, brain edema, intracerebral hemorrhage, neurological function and mortality rate in all 47 included studies. Standardized mean differences for continuous measures and risk ratio for dichotomous measures were calculated to assess the effects of endogenous tPA and rtPA on cerebral infarction in animals. The quality of included studies was assessed using the Stroke Therapy Academic Industry Roundtable score. Subgroup analysis, meta-regression and sensitivity analysis were performed to explore sources of heterogeneity. Funnel plot, Trim and Fill method and Egger’s test were obtained to detect publication bias. Results We found that both endogenous tPA and rtPA had not enlarged infarction volume, or deteriorated neurological function. However, rtPA would disrupt blood-brain barrier, aggravate brain edema, induce intracerebral hemorrhage and increase mortality rate. Conclusions This meta-analysis reveals rtPA can lead to neurological side effects besides thrombolysis in mechanical animal stroke, which may account for clinical exacerbation for stroke patients that do not achieve vascular recanalization with rtPA. PMID:27387385

  14. Recombinant Tissue Plasminogen Activator Induces Neurological Side Effects Independent on Thrombolysis in Mechanical Animal Models of Focal Cerebral Infarction: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Mei-Xue Dong

    Full Text Available Recombinant tissue plasminogen activator (rtPA is the only effective drug approved by US FDA to treat ischemic stroke, and it contains pleiotropic effects besides thrombolysis. We performed a meta-analysis to clarify effect of tissue plasminogen activator (tPA on cerebral infarction besides its thrombolysis property in mechanical animal stroke.Relevant studies were identified by two reviewers after searching online databases, including Pubmed, Embase, and ScienceDirect, from 1979 to 2016. We identified 6, 65, 17, 12, 16, 12 and 13 comparisons reporting effect of endogenous tPA on infarction volume and effects of rtPA on infarction volume, blood-brain barrier, brain edema, intracerebral hemorrhage, neurological function and mortality rate in all 47 included studies. Standardized mean differences for continuous measures and risk ratio for dichotomous measures were calculated to assess the effects of endogenous tPA and rtPA on cerebral infarction in animals. The quality of included studies was assessed using the Stroke Therapy Academic Industry Roundtable score. Subgroup analysis, meta-regression and sensitivity analysis were performed to explore sources of heterogeneity. Funnel plot, Trim and Fill method and Egger's test were obtained to detect publication bias.We found that both endogenous tPA and rtPA had not enlarged infarction volume, or deteriorated neurological function. However, rtPA would disrupt blood-brain barrier, aggravate brain edema, induce intracerebral hemorrhage and increase mortality rate.This meta-analysis reveals rtPA can lead to neurological side effects besides thrombolysis in mechanical animal stroke, which may account for clinical exacerbation for stroke patients that do not achieve vascular recanalization with rtPA.

  15. Experimental study on effects of CBM temperature-rising desorption

    Institute of Scientific and Technical Information of China (English)

    MA Dong-min; LIN Ya-bing

    2012-01-01

    To study the effects of CBM (coal bed methane) temperature-rising desorption,isothermal adsorption/desorption experiments on three ranks (anthracite,coking coal and lignite) of coal at different temperatures were designed based on the traditional CBM decompression desorption.The experimental results indicate that temperature-rising desorption is more effective in high-rank coal,and ever-increasing temperature of high-rank coal reservoir can reduce the negative effects of coal matrix shrinkage in the process of production and improve the permeability of the coal reservoir as well.It is also revealed that the technique of temperature-rising desorption applied in higher-rank coal reservoir can enhance CBM recovery ratio.This study provided theoretical support for the application of temperature-rising desorption technique in practical discharging and mining projects,which can effectively tackle the gas production bottleneck problem.

  16. The effect of selective desorption mechanisms during interstellar ice formation

    CERN Document Server

    Kalvans, Juris

    2015-01-01

    Major components of ices on interstellar grains in molecular clouds - water and carbon oxides - occur at various optical depths. This implies that selective desorption mechanisms are at work. An astrochemical model of a contracting low-mass molecular cloud core is presented. Ice was treated as consisting of the surface and three subsurface layers (sublayers). Photodesorption, reactive desorption, and indirect reactive desorption were investigated. The latter manifests itself through desorption from H+H reaction on grains. Desorption of shallow subsurface species was included. Modeling results suggest the existence of a "photon-dominated ice" during the early phases of core contraction. Subsurface ice is chemically processed by interstellar photons, which produces complex organic molecules. Desorption from the subsurface layer results in high COM gas-phase abundances at Av = 2.4...10mag. This may contribute towards an explanation for COM observations in dark cores. It was found that photodesorption mostly gove...

  17. Effects of Lateral Diffusion on the Dynamics of Desorption

    OpenAIRE

    Juwono, Tjipto; Hamad, Ibrahim Abou; Rikvold, Per Arne

    2012-01-01

    The adsorbate dynamics during simultaneous action of desorption and lateral adsorbate diffusion is studied in a simple lattice-gas model by kinetic Monte Carlo simulations. It is found that the action of the coverage-conserving diffusion process during the course of the desorption has two distinct, competing effects: a general acceleration of the desorption process, and a coarsening of the adsorbate configuration through Ostwald ripening. The balance between these two effects is governed by t...

  18. Displacement desorption test of coalbed methane and its mechanism exploring

    Institute of Scientific and Technical Information of China (English)

    ZHANG Suian; HUO Yongzhong; YE Jianping; TANG Shuheng; MA Dongmin

    2005-01-01

    Through the test of CH4 displaced by CO2 using the coal sample as the adsorbent, this paper has found the coalbed methane (CBM) displacement desorption phenomenon under the natural conditions and CBM mining conditions. With the help of the adsorption theory of the modern physical chemistry and interfacial chemistry, the CBM competitive adsorption and displacement desorption mechanism are intensively discussed, and a new path for studying the CBM desorption mechanism in the CBM exploitation process is explored.

  19. Substrate-Enhanced Micro Laser Desorption Ionization Mass Spectrometry Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Aerodyne Research, Inc. and the University of Massachusetts at Amherst will collaborate to develop laser desorption ionization (LDI) mass spectrometric analysis of...

  20. Effects of Lateral Diffusion on the Dynamics of Desorption

    CERN Document Server

    Juwono, Tjipto; Rikvold, Per Arne

    2012-01-01

    The adsorbate dynamics during simultaneous action of desorption and lateral adsorbate diffusion is studied in a simple lattice-gas model by kinetic Monte Carlo simulations. It is found that the action of the coverage-conserving diffusion process during the course of the desorption has two distinct, competing effects: a general acceleration of the desorption process, and a coarsening of the adsorbate configuration through Ostwald ripening. The balance between these two effects is governed by the structure of the adsorbate layer at the beginning of the desorption process.

  1. Testosterone sorption and desorption: Effects of soil particle size

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Yong, E-mail: yqi01@unomaha.edu [Civil Engineering Dept., University of Nebraska-Lincoln at Omaha Campus, Omaha, NE 68182 (United States); Zhang, Tian C. [Civil Engineering Dept., University of Nebraska-Lincoln at Omaha Campus, Omaha, NE 68182 (United States); Ren, Yongzheng [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-08-30

    Graphical abstract: - Highlights: • Smaller soil particles have higher sorption and lower desorption rates. • The sorption capacity ranks as clay > silt > sand. • Small particles like clays have less potential for desorption. • Colloids (clays) have high potential to facilitate the transport of hormones in soil–water environments. - Abstract: Soils contain a wide range of particles of different diameters with different mobility during rainfall events. Effects of soil particles on sorption and desorption behaviors of steroid hormones have not been investigated. In this study, wet sieve washing and repeated sedimentation methods were used to fractionate the soils into five ranges. The sorption and desorption properties and related mechanisms of testosterone in batch reactors filled with fractionated soil particles were evaluated. Results of sorption and desorption kinetics indicate that small soil particles have higher sorption and lower desorption rates than that of big ones. Thermodynamic results show the sorption processes are spontaneous and exothermal. The sorption capacity ranks as clay > silt > sand, depending mainly on specific surface area and surface functional groups. The urea control test shows that hydrogen bonding contributes to testosterone sorption onto clay and silt but not on sand. Desorption tests indicate sorption is 36–65% irreversible from clay to sand. Clays have highest desorption hysteresis among these five soil fractions, indicating small particles like clays have less potential for desorption. The results provide indirect evidence on the colloid (clay)-facilitated transport of hormones (micro-pollutants) in soil environments.

  2. Desorption of copper from polyvinyl alcohol-immobilized seaweed biomass

    Energy Technology Data Exchange (ETDEWEB)

    Chu, K.H. [Swinburne Univ. of Technology, Hawthorn, Vic. (Australia). School of Engineering and Science; Hashim, M.A. [Malaya Univ., Kuala Lumpur (Malaysia). Dept. of Chemical Engineering

    2001-07-01

    The desorption characteristics of copper on biomass of a marine macroalga, Sargassum baccularia, immobilized in polyvinyl alcohol (PVA) gel beads, were investigated using HCl eluting solutions. Both the extent and the rate of desorption were affected by the pH of the eluent. Nearly 91% of the copper initially adsorbed was released back into an HCl solution at pH 1.0 after 40 min of contact time when apparent desorption equilibrium was achieved. When the pH was raised t0 2.0, about 81% of the bound copper was desorbed within 120 min of contact time. Apparent desorption rate constants were determined using first-order desorption models. Very high concentrations of copper in the eluate could be obtained by using small amounts of the HCl eluent. However, this was achieved at the expense of the desorption efficiency. The PVA-immobilized seaweed biomass beads could be regenerated with HCl solution at pH 1.0 or 2.0 in multiple cycles of copper biosorption-desorption. Following desorption at pH 1.0 in the first cycle, about 55% of the biosorption capacity of the virgin biomass could be reused in subsequent cycles; in the case of desorption at pH 2.0, about 67% of the original uptake capacity was reusable. (orig.)

  3. Estrogen receptors bind to and activate the HOXC4/HoxC4 promoter to potentiate HoxC4-mediated activation-induced cytosine deaminase induction, immunoglobulin class switch DNA recombination, and somatic hypermutation.

    Science.gov (United States)

    Mai, Thach; Zan, Hong; Zhang, Jinsong; Hawkins, J Seth; Xu, Zhenming; Casali, Paolo

    2010-11-26

    Estrogen enhances antibody and autoantibody responses through yet to be defined mechanisms. It has been suggested that estrogen up-regulates the expression of activation-induced cytosine deaminase (AID), which is critical for antibody class switch DNA recombination (CSR) and somatic hypermutation (SHM), through direct activation of this gene. AID, as we have shown, is induced by the HoxC4 homeodomain transcription factor, which binds to a conserved HoxC4/Oct site in the AICDA/Aicda promoter. Here we show that estrogen-estrogen receptor (ER) complexes do not directly activate the AID gene promoter in B cells undergoing CSR. Rather, they bind to three evolutionarily conserved and cooperative estrogen response elements (EREs) we identified in the HOXC4/HoxC4 promoter. By binding to these EREs, ERs synergized with CD154 or LPS and IL-4 signaling to up-regulate HoxC4 expression, thereby inducing AID and CSR without affecting B cell proliferation or plasmacytoid differentiation. Estrogen administration in vivo significantly potentiated CSR and SHM in the specific antibody response to the 4-hydroxy-3-nitrophenylacetyl hapten conjugated with chicken γ-globulin. Ablation of HoxC4 (HoxC4(-/-)) abrogated the estrogen-mediated enhancement of AID gene expression and decreased CSR and SHM. Thus, estrogen enhances AID expression by activating the HOXC4/HoxC4 promoter and inducing the critical AID gene activator, HoxC4.

  4. Desorption of trihalomethanes in gas liquid contactors

    International Nuclear Information System (INIS)

    Updated studies show that gastric cancer is related with the existence of trihalomethanes (THMs) in the drinking water. The trihalomethanes are sub products from the degradation of humic acids and your reaction with chlorine and bromine used like decontaminates. The desorption process is used to eliminate the THMs with air in contact with the water. The experimental design was used in three contactors. The contactors selected were: the bubbling's column, the packed column and the shaken tank without screen. There were selected three variable: initial concentration of THMs, the residence time and the turbulence degree (measured with the Reynolds number). The concentrations were made with a gas chromatograph. The objective of this project is to do a comparison with the gas liquid contactors more used in the industrial level to determinate which ones are the best in the desorption process. The conclusion of the experimental design is that the tank is the equipment with the best capacity to eliminate THMs. Too it includes other techniques to eliminate THMs of the water and your treatment

  5. Laser Infrared Desorption Spectroscopy to Detect Complex Organic Molecules on Icy Planetary Surfaces

    Science.gov (United States)

    Sollit, Luke S.; Beegle, Luther W.

    2008-01-01

    Laser Desorption-Infrared Spectroscopy (LD-IR) uses an IR laser pulse to desorb surface materials while a spectrometer measures the emission spectrum of the desorbed materials (Figure 1). In this example, laser desorption operates by having the incident laser energy absorbed by near surface material (10 microns in depth). This desorption produces a plume that exists in an excited state at elevated temperatures. A natural analog for this phenomenon can be observed when comets approach the sun and become active and individual molecular emission spectra can be observed in the IR [1,2,3,4,5]. When this occurs in comets, the same species that initially emit radiation down to the ground state are free to absorb it, reducing the amount of detectable emission features. The nature of our technique results in absorption not occurring, because the laser pulse could easily be moved away form the initial desorption plume, and still have better spatial resolution then reflectance spectroscopy. In reflectance spectroscopy, trace components have a relatively weak signal when compared to the entire active nature of the surface. With LDIR, the emission spectrum is used to identify and analyze surface materials.

  6. A Recombination Directionality Factor Controls the Cell Type-Specific Activation of σK and the Fidelity of Spore Development in Clostridium difficile

    Science.gov (United States)

    Serrano, Mónica; Kint, Nicolas; Pereira, Fátima C.; Saujet, Laure; Boudry, Pierre; Dupuy, Bruno; Martin-Verstraete, Isabelle

    2016-01-01

    The strict anaerobe Clostridium difficile is the most common cause of nosocomial diarrhea, and the oxygen-resistant spores that it forms have a central role in the infectious cycle. The late stages of sporulation require the mother cell regulatory protein σK. In Bacillus subtilis, the onset of σK activity requires both excision of a prophage-like element (skinBs) inserted in the sigK gene and proteolytical removal of an inhibitory pro-sequence. Importantly, the rearrangement is restricted to the mother cell because the skinBs recombinase is produced specifically in this cell. In C. difficile, σK lacks a pro-sequence but a skinCd element is present. The product of the skinCd gene CD1231 shares similarity with large serine recombinases. We show that CD1231 is necessary for sporulation and skinCd excision. However, contrary to B. subtilis, expression of CD1231 is observed in vegetative cells and in both sporangial compartments. Nevertheless, we show that skinCd excision is under the control of mother cell regulatory proteins σE and SpoIIID. We then demonstrate that σE and SpoIIID control the expression of the skinCd gene CD1234, and that this gene is required for sporulation and skinCd excision. CD1231 and CD1234 appear to interact and both proteins are required for skinCd excision while only CD1231 is necessary for skinCd integration. Thus, CD1234 is a recombination directionality factor that delays and restricts skinCd excision to the terminal mother cell. Finally, while the skinCd element is not essential for sporulation, deletion of skinCd results in premature activity of σK and in spores with altered surface layers. Thus, skinCd excision is a key element controlling the onset of σK activity and the fidelity of spore development. PMID:27631621

  7. Selective desorption of carbon dioxide from sewage sludge for in-situ methane enrichment: Enrichment experiments in pilot scale

    International Nuclear Information System (INIS)

    The application of in-situ methane enrichment for upgrading the biogas from anaerobic digestion to vehicle fuel or natural gas quality, has been studied in pilot scale and by computer simulation of the desorption step. Pilot plant experiments have been performed using a 19 m3 and 15 m3 continuously stirred tank reactor operating with municipal sewage sludge at mesophilic conditions connected respectively to a 90 dm3 and 140 dm3 external bubble column for selective desorption of CO2. The results show that the CH4 yield is unchanged during the experiments, and accordingly there is no evidence that the oxygen in the air used in the desorption of CO2 has a negative impact on the CH4 producing activity. The sludge recirculation system must be designed to avoid leakage of air into the digester, in order to maintain a low N2 concentration in the biogas. At best, a biogas with a volume fraction of 87% CH4 and φN2 = 2% was obtained. The CH4 loss however amounted to 8%, which is unsatisfactory. The experimental results are compared with previous data in the literature and explanations are deducted for the difference in the performance. Computer simulations reveal that the sludge flow rate recirculated through the desorption column should be as low as possible to minimize the loss of CH4. An increased air flow rate through the desorption column and an increased desorption column volume will promote the desorption of CO2 and improve the ratio of CO2 to CH4 desorption. -- Highlights: ► In-situ methane enrichment for biogas upgrading. ► The methane yield is unchanged. ► Methane concentration of 87% obtained. ► The sludge flow rate should be low. ► The aeration rate should be high.

  8. Detection of platelet-derived growth factor (PDGF)-AA in actively healing human wounds treated with recombinant PDGF-BB and absence of PDGF in chronic nonhealing wounds.

    OpenAIRE

    Pierce, G F; Tarpley, J. E.; Tseng, J; Bready, J; Chang, D.; Kenney, W C; Rudolph, R; Robson, M. C.; Vande Berg, J.; Reid, P.

    1995-01-01

    Some human chronic dermal wounds treated with recombinant platelet-derived growth factor-BB (rPDGF-BB) show increased healing coupled with fibroblast activation and granulation tissue formation. To determine whether endogenous PDGF is associated with healing and nonhealing dermal ulcer phenotypes, we developed monoclonal antibodies capable of recognizing the three isoforms of PDGF, AA, AB, and BB dimers, and capable of discriminating between two alternatively spliced A chain transcripts. We d...

  9. Human lymphokine-activated killer cell system. V. Purified recombinant interleukin 2 activates cytotoxic lymphocytes which lyse both natural killer-resistant autologous and allogeneic tumors and trinitrophenyl-modified autologous peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    Culture of human peripheral blood lymphocytes (PBL) in purified natural or recombinant interleukin 2 in the absence of exogenous antigen or mitogen causes the differentiation of nonlytic precursor cells into lymphokine-activated killers (LAK). A titration of purified Jurkat IL-2 (BRMP, FCRC, NIH) IL-2 showed that the relatively low concentration of 5 U/ml was optimal for LAK activation. When the responding PBL were pretreated with either mitomycin C or gamma irradiation, LAK activation did not occur, indicating that proliferation, in addition to differentiation, is required. The spectrum of target cells susceptible to LAK lysis in a 4-hr chromium-51-release assay includes fresh NK-resistant tumor cells and trinitrophenyl (TNP)-modified autologous PBL. Unmodified PBL are not lysed. Cold target inhibition studies indicated that LAK lysis of autologous TNP-PBL is totally inhibited by fresh tumors cells, and that tumor lysis is inhibited by TNP-PBL. Additionally, allogeneic tumors totally inhibit lysis of autologous tumor cells in other cold target studies. These results demonstrate that the lytic activity expressed by LAK is not HLA restricted, is not limited to tumor cells, and is polyspecific as indicated by the cross-reactive recognition of multiple target cell types in these cold target inhibition studies

  10. Forced desorption of semiflexible polymers, adsorbed and driven by molecular motors

    CERN Document Server

    Chaudhuri, Abhishek

    2014-01-01

    We formulate and characterize a model to describe dynamics of semiflexible polymers in the presence of activity due to motor proteins attached irreversibly to a substrate, and a transverse pulling force acting on one end of the filament. The stochastic binding-unbinding of the motor proteins and their ability to move along the polymer, generates active forces. As the pulling force reaches a threshold value, the polymer eventually desorbs from the substrate. We present a mean field theory that predicts increase in desorption force with polymer bending rigidity, active velocity and processivity of the motor proteins. Performing molecular dynamics simulations of the polymer in presence of a Langevin heat bath, and stochastic motor activity we obtain desorption phase diagrams that show good agreement with theory. With increase in pulling force, the polymer undergoes a first order phase transition from mostly adsorbed to fully desorbed state via a regime of coexistence where the steady state dynamics of the polyme...

  11. Recombinant Human Erythropoietin Protects Myocardial Cells from Apoptosis via the Janus-Activated Kinase 2/Signal Transducer and Activator of Transcription 5 Pathway in Rats with Epilepsy

    Directory of Open Access Journals (Sweden)

    Bao-Xin Ma, MD

    2015-12-01

    Conclusions: These results indicate that myocardial cell apoptosis may contribute to myocardial injury in epilepsy. EPO protects myocardial cells from apoptosis via the JAK2/STAT5 pathway in rats with experimental epilepsy, whereas CEPO exerts antiapoptotic activity perhaps via a pathway independent of JAK2/STAT5 signaling.

  12. Recombinant allergens: what does the future hold?

    Science.gov (United States)

    Valenta, Rudolf; Niespodziana, Katarzyna; Focke-Tejkl, Margit; Marth, Katharina; Huber, Hans; Neubauer, Angela; Niederberger, Verena

    2011-04-01

    This year we are celebrating not only the centenary of allergen-specific immunotherapy but also the 10-year anniversary of the first administration of recombinant allergen-based vaccines to allergic patients. By using recombinant DNA technology, defined and safe allergy vaccines can be produced that allow us to overcome many, if not all, of the problems associated with the use of natural allergen extracts, such as insufficient quality, allergenic activity, and poor immunogenicity. Here we provide an update of clinical studies with recombinant allergen-based vaccines, showing that some of these vaccines have undergone successful clinical evaluation up to phase III studies. Furthermore, we introduce a strategy for allergen-specific immunotherapy based on recombinant fusion proteins consisting of viral carrier proteins and allergen-derived peptides without allergenic activity, which holds the promise of being free of side effects and eventually being useful for prophylactic vaccination.

  13. Sorption and desorption of indaziflam degradates in several agricultural soils

    Science.gov (United States)

    Processes regulating pesticide fate in the environment are influenced by the physicochemical properties of pesticides and soils. Sorption-desorption are important processes as they regulate movement of pesticides in soil. Although sorption-desorption is widely studied for herbicides, studies involvi...

  14. Desorption process of deuterium from zircaloys and their oxides

    Energy Technology Data Exchange (ETDEWEB)

    Nakamichi, Haruo; Kinoshita, Chiken; Hara, Masahiro [Kyushu Univ., Fukuoka (Japan)

    1997-11-01

    It is well known that hydrogen behavior plays an important role on the oxidation process of zircaloys. We have investigated the desorption process of deuterium from three kinds of zircaloys (Zry-2, Zry-4 and high-Fe and Ni-Zry-2) and their oxides using thermal desorption spectrometry (TDS). The purpose of the present paper is to get insight into the effect of alloying elements on the desorption behavior of deuterium from the zircaloys and their oxides. We have also performed in-situ observations through TEM for getting the relation between the desorption process and microstructural evolution. The desorption of D{sub 2} implanted by an ion accelerator occurs in two stages; the first and the second stages appear at around 350 K and around 700 K for the metallic zircaloys, respectively. For their oxide films, on the other hand, the desorption rate of D{sub 2} is much higher than that for the metallic zircaloys. It is found that the desorption rate depends strongly on the kind of zircaloys, especially on the concentration of Fe and Ni. From TEM result, it is found that the first desorption stage for the metallic specimens is correlated to the dissolution of the hydrides. (author)

  15. CO and N$_2$ desorption energies from water ice

    CERN Document Server

    Fayolle, Edith C; Loomis, Ryan; Bergner, Jennifer; Graninger, Dawn M; Rajappan, Mahesh; Öberg, Karin I

    2015-01-01

    The relative desorption energies of CO and N$_2$ are key to interpretations of observed interstellar CO and N$_2$ abundance patterns, including the well-documented CO and N$_2$H$^+$ anti-correlations in disks, protostars and molecular cloud cores. Based on laboratory experiments on pure CO and N$_2$ ice desorption, the difference between CO and N$_2$ desorption energies is small; the N$_2$-to-CO desorption energy ratio is 0.93$\\pm$0.03. Interstellar ices are not pure, however, and in this study we explore the effect of water ice on the desorption energy ratio of the two molecules. We present temperature programmed desorption experiments of different coverages of $^{13}$CO and $^{15}$N$_2$ on porous and compact amorphous water ices and, for reference, of pure ices. In all experiments, $^{15}$N$_2$ desorption begins a few degrees before the onset of $^{13}$CO desorption. The $^{15}$N$_2$ and $^{13}$CO energy barriers are 770 and 866 K for the pure ices, 1034-1143 K and 1155-1298 K for different sub-monolayer co...

  16. Characterization of foot- and mouth disease virus antigen by surface-enhanced laser desorption ionization-time of flight-mass spectrometry in aqueous and oil-emulsion formulations

    NARCIS (Netherlands)

    Harmsen, M.M.; Jansen, J.; Westra, D.F.; Coco-Martin, J.M.

    2010-01-01

    We have used a novel method, surface-enhanced laser desorption ionization-time of flight-mass spectrometry (SELDI-TOF-MS), to characterize foot-and-mouth disease virus (FMDV) vaccine antigens. Using specific capture with FMDV binding recombinant antibody fragments and tryptic digestion of FMDV antig

  17. Integrated field emission array for ion desorption

    Energy Technology Data Exchange (ETDEWEB)

    Resnick, Paul J; Hertz, Kristin L; Holland, Christopher; Chichester, David; Schwoebel, Paul

    2013-09-17

    An integrated field emission array for ion desorption includes an electrically conductive substrate; a dielectric layer lying over the electrically conductive substrate comprising a plurality of laterally separated cavities extending through the dielectric layer; a like plurality of conically-shaped emitter tips on posts, each emitter tip/post disposed concentrically within a laterally separated cavity and electrically contacting the substrate; and a gate electrode structure lying over the dielectric layer, including a like plurality of circular gate apertures, each gate aperture disposed concentrically above an emitter tip/post to provide a like plurality of annular gate electrodes and wherein the lower edge of each annular gate electrode proximate the like emitter tip/post is rounded. Also disclosed herein are methods for fabricating an integrated field emission array.

  18. Integrated field emission array for ion desorption

    Energy Technology Data Exchange (ETDEWEB)

    Resnick, Paul J; Hertz, Kristin L.; Holland, Christopher; Chichester, David

    2016-08-23

    An integrated field emission array for ion desorption includes an electrically conductive substrate; a dielectric layer lying over the electrically conductive substrate comprising a plurality of laterally separated cavities extending through the dielectric layer; a like plurality of conically-shaped emitter tips on posts, each emitter tip/post disposed concentrically within a laterally separated cavity and electrically contacting the substrate; and a gate electrode structure lying over the dielectric layer, including a like plurality of circular gate apertures, each gate aperture disposed concentrically above an emitter tip/post to provide a like plurality of annular gate electrodes and wherein the lower edge of each annular gate electrode proximate the like emitter tip/post is rounded. Also disclosed herein are methods for fabricating an integrated field emission array.

  19. Silver impregnated carbon for adsorption and desorption of elemental mercury vapors

    Institute of Scientific and Technical Information of China (English)

    Despina Karatza; Marina Prisciandaro; Amedeo Lancia; Dino Musmarra

    2011-01-01

    The Hg0 vapor adsorption experimental results on a novel sorbent obtained by impregnating a commercially available activated carbon (Darco G60 from BDH) with silver nitrate were reported.The study was performed by using a fundamental approach,in an apparatus at laboratory scale in which a synthetic flue gas,formed by Hg0 vapors in a nitrogen gas stream,at a given temperature and mercury concentration,was flowed through a fixed bed of adsorbent material.Breakthrough curves and adsorption isotherms were obtained for bed temperatures of 90,120 and 150°C and for Hg0 concentrations in the gas varying in the range of 0.8-5.0 mg/m3.The experimental gas-solid equilibrium data were used to evaluate the Langmuir parameters and the heat of adsorption.The experimental results showed that silver impregnated carbon was very effective to capture elemental mercury and the amount of mercury adsorbed by the carbon decreased as the bed temperature increased.In addition,to evaluate the possibility of adsorbent recovery,desorption was also studied.Desorption runs showed that both the adsorbing material and the mercury could be easily recovered,since at the end of desorption the residue on solid was almost negligible.The material balance on mercury and the constitutive equations of the adsorption phenomenon were integrated,leading to the evaluation of only one kinetic parameter which fits well both the experimentally determined breakthrough and desorption curves.

  20. Influence of Organic Amendments on Adsorption, Desorption and Leaching of Methiopyrisulfuron in Soils

    Institute of Scientific and Technical Information of China (English)

    WU Chun-xian; NIE Guo; ZHANG Zhong-ming; WANG Guang-cheng; GAO Li-ming; WANG Jin-jun

    2013-01-01

    Methiopyrisulfuron is a novel sulfonylurea herbicide with good activity for annual broadleaf and gramineal weeds control. Present study was to investigate the effects of organic amendments (including peat (PE), sewage sludge (SS), and humic acid (HA)) on adsorption, desorption and leaching of methiopyrisulfuron in soils. The batch equilibration technique was applied for adsorption-desorption experiments and the leaching was tested through soil column simulated experiments under laboratory conditions. The Freundlich model may well describe adsorption-desorption of methiopyrisulfuron on organic amendments, the natural soil, and amended soils. Organic amendments could not only greatly increase the adsorption capacity of methiopyrisulfuron, but also significantly enhance the hysteresis of desorption of methiopyrisulfuron. The correlations between Kf-ads and organic matter content of amended soils were significant, and the correlations between H and soil organic matter in amended soils with PE, SS, and HA were significant too. The results of soil column experiments indicated that organic amendments greatly decreased leaching of methiopyrisulfuron. This study suggested that PE, SS, and HA could greatly influence environmental behavior of methiopyrisulfuron in soils. Use of organic amendments might be an effective management practice for controlling potential pollution of methiopyrisulfuron to environment.

  1. Palifermin (recombinant keratinocyte growth factor-1): a pleiotropic growth factor with multiple biological activities in preventing chemotherapy- and radiotherapy-induced mucositis.

    NARCIS (Netherlands)

    Blijlevens, N.M.A.; Sonis, S.T.

    2007-01-01

    Oral and intestinal mucositis are among the most significant dose-limiting toxic effects of intensive cancer treatment and are associated with adverse clinical and economic outcomes. Palifermin (Kepivancetrade mark), an N-truncated recombinant human keratinocyte growth factor-1, is the first agent t

  2. Recombinant methods and materials

    Energy Technology Data Exchange (ETDEWEB)

    Roizman, B.; Post, L.E.

    1988-09-06

    This patent describes a method for stably effecting the insertion or deletion of a selected DNA sequence at a specific site in a viral genome. The method consists of: (1) isolating from the genome a linear DNA fragment comprising both (a) the specific site determined for insertion or deletion of selected DNA sequence and (b) flanking DNA sequences normally preceding and following the site; (2) preparing first and second altered genome fragments from the fragment isolated in step (1). (a) the first altered fragment comprising the fragment comprising a thymidine kinase gene in a position intermediate the ends of the fragment, and (b) the second altered fragment comprising the fragment having the selected DNA sequence inserted therein or deleted therefrom; (3) contacting the genome with the first altered fragment under conditions permitting recombination at sites of DNA sequence homology, selecting for a recombinant genome comprising the thymidine kinase gene, and isolating the recombinant genome; and (4) contacting the recombinant genome isolated in step (3) with the second altered fragment under conditions permitting recombination at sites of DNA sequence homology, selecting for a recombinant genome lacking the thymidine kinase gene, and isolating the recombinant genome product.

  3. Uso de fator VII recombinante ativado para tratamento e profilaxia de grandes sangramentos Use of recombinant activated factor VII for treatment and prophylaxis of major bleeding

    Directory of Open Access Journals (Sweden)

    Flávio Augusto Henriques Vince

    2009-09-01

    pacientes. Dessa forma, o recente aumento do uso de rFVIIa em situações ainda não aprovadas levou ao crescente questionamento sobre eficácia e segurança desta específica medicação em tais situações.INTRODUCTION: Recombinant activated factor VII (rFVIIa is a protein produced by genetic engineering, the structure is very similar to the structure of intrinsic activated factor VII (FVII. Its action is based on knowledge of the coagulation mechanism in vivo by acting in direct activation of factor X independent resulting in formation of thrombin at the injury site and thereby contributing to the formation of stable fibrin clots without the action of factor VIII and factor IX. METHODS: Was conducted extensive review of the literature in order to determine the new findings related to the use of recombinant activated factor VII in patients with severe bleeding. RESULTS: It was found that the use of rFVIIa started in the 80's for prophylaxis and treatment of bleeding in patients with a history of hemophilia A or B with inhibitors to factor VIII and IX, factor VII deficiency and Glanzmann's thrombasthenia refractory to replacement platelet. In 1999 its use was expanded to other clinical situations and thus began to be published several studies showing the efficacy of rFVIIa as a pro-hemostatic agent in patients with bleeding disorders or other previously healthy patients with a history of acute bleeding of major consequence. Trauma is the leading cause of mortality worldwide and uncontrolled bleeding the main challenge in caring for these patients. It is common for the association of trauma with coagulopathy, requiring in some cases specific therapy to treat it. At this point in adjuvant therapy with rFVIIa should be considered. Other common causes of bleeding are the heart, gynecologic/obstetric surgeries and diseases involving the liver. The coagulopathy in these cases is deficiency of factors dependent on vitamin K, and the FVII factor with smaller half life. CONCLUSION

  4. High-Mannose Specific Lectin and Its Recombinants from a Carrageenophyta Kappaphycus alvarezii Represent a Potent Anti-HIV Activity Through High-Affinity Binding to the Viral Envelope Glycoprotein gp120.

    Science.gov (United States)

    Hirayama, Makoto; Shibata, Hiromi; Imamura, Koji; Sakaguchi, Takemasa; Hori, Kanji

    2016-04-01

    We previously reported that a high-mannose binding lectin KAA-2 from the red alga Kappaphycus alvarezii, which is an economically important species and widely cultivated as a source of carrageenans, had a potent anti-influenza virus activity. In this study, the full-length sequences of two KAA isoforms, KAA-1 and KAA-2, were elucidated by a combination of peptide mapping and cDNA cloning. They consisted of four internal tandem-repeated domains, which are conserved in high-mannose specific lectins from lower organisms, including a cyanobacterium Oscillatoria agardhii and a red alga Eucheuma serra. Using an Escherichia coli expression system, an active recombinant form of KAA-1 (His-tagged rKAA-1) was successfully generated in the yield of 115 mg per a litter of culture. In a detailed oligosaccharide binding analysis by a centrifugal ultrafiltration-HPLC method with 27 pyridylaminated oligosaccharides, His-tagged rKAA-1 and rKAA-1 specifically bound to high-mannose N-glycans with an exposed α1-3 mannose in the D2 arm as the native lectin did. Predicted from oligosaccharide-binding specificity, a surface plasmon resonance analysis revealed that the recombinants exhibit strong interaction with gp120, a heavily glycosylated envelope glycoprotein of HIV with high association constants (1.48-1.61 × 10(9) M(-1)). Native KAAs and the recombinants inhibited the HIV-1 entry at IC50s of low nanomolar levels (7.3-12.9 nM). Thus, the recombinant proteins would be useful as antiviral reagents targeting the viral surface glycoproteins with high-mannose N-glycans, and the cultivated alga K. alvarezii could also be a good source of not only carrageenans but also this functional lectin(s). PMID:26661793

  5. Complete solubilization and purification of recombinant human growth hormone produced in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Min-Ji Kim

    Full Text Available High-level expression of recombinant human growth hormone (hGH in Escherichia coli (E. coli leads to the formation of insoluble aggregates as inclusion bodies devoid of biological activity. Until recently, significant efforts have been made to improve the recovery of active hGH from inclusion bodies. Here, we developed an efficient procedure for the production of completely soluble hGH by minimizing the formation of inclusion bodies and optimizing protein purification conditions. Under the newly established conditions we were able to obtain most of the total hGH in the soluble fraction. We show that the soluble protein can be efficiently purified in high yield by a series of chromatographic procedures. We analyzed the resulting hGH using various analytical techniques such as reversed-phase high-performance liquid chromatography (RP-HPLC, size-exclusion chromatography (SEC, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF mass spectrometry, and circular dichroism (CD. These multiple analyses support the conclusion that we obtained highly pure hGH with the expected molecular mass and intact secondary structure. The biological activity of purified hGH was also confirmed by evaluating its growth-promoting effect using a cell proliferation assay. Taken together, we describe a straightforward strategy for the production of completely soluble and biologically active hGH in E. coli.

  6. Recombinant erythropoietin for the anaemia of patients with advanced Gastrointestinal Stromal Tumours (GIST receiving imatinib: an active agent only in non progressive patients

    Directory of Open Access Journals (Sweden)

    Duffaud Florence

    2012-09-01

    Full Text Available Abstract Recombinant erythropoietin for the anaemia of patients with advanced Gastrointestinal Stromal Tumours (GIST receiving imatinib : an active agent only in non progressive patients. Background Imatinib is a standard treatment for advanced/metastatic GIST and in adjuvant setting. Anaemia is frequently observed in patients with advanced GIST, and is one of the most frequent side effects of imatinib with grade 3–4 anaemia in 10% of patients. Whether EPO treatment is useful in the management of GIST patients receiving imatinib treatment is unknown. Methods A retrospective study of EPO treatment in GIST patients receiving imatinib was undertaken in 4 centres. Thirty four patients received EPO treatment among the 319 GIST patients treated with imatinib in clinical trials or with compassionate use between 2001 and 2003. The efficacy of EPO on the anaemia of patients with GIST treated with imatinib was analyzed. Results There were 18 males and 16 females with a median age of 59 years. Median WHO-PS was 1. Primary tumour sites were mainly gastric (32% and small bowel (29%. Sites of metastases were mainly liver (82% and peritoneum (79%. The median delay between the initiation of imatinib treatment and EPO was 58 days (range 0–553. Median haemoglobin (Hb level prior to EPO was 9 g/dL (range 6,9-11,8 and 11,7 g/dL (range 6,8-14,4 after 2 months. An increase of more than 2 g/dL was observed in 18 (53% of patients. None of the 7 patients who progressed (PD under imatinib treatment (400 mg/day experienced HB response, as compared to 66% (18/27 of the remaining patients (PR + SD (p = 0,002. Primary tumour site, liver metastases, peritoneal metastases, age, gender did not correlate with HB response to EPO. Response to EPO was observed in 2/11 patients receiving high-dose imatinib (800 mg/day vs 16/23 of others. Using logistic regression, only PD before EPO treatment was retained as a predictive factor for EPO response. Conclusion EPO enables to

  7. Recombinant Escherichia coli produces tailor-made biopolyester granules for applications in fluorescence activated cell sorting: functional display of the mouse interleukin-2 and myelin oligodendrocyte glycoprotein

    Directory of Open Access Journals (Sweden)

    Brockelbank Jane A

    2007-01-01

    Full Text Available Abstract Background Fluorescence activated cell sorting (FACS is a powerful technique for the qualitative and quantitative detection of biomolecules used widely in both basic research and clinical diagnostic applications. Beads displaying a specific antigen are used to bind antibodies which are then fluorescently labelled using secondary antibodies. As the individual suspension bead passes through the sensing region of the FACS machine, fluorescent signals are acquired and analysed. Currently, antigens are tediously purified and chemically cross-linked to preformed beads. Purification and coupling of proteins often renders them inactive and they will not be displayed in its native configuration. As an alternative, we genetically engineered Escherichia coli to produce biopolyester (polyhdroxyalkanoate=PHA granules displaying diagnostically relevant antigens in their native conformation and suitable for FACS analysis. Results Hybrid genes were constructed, which encode either the mouse interleukin-2 (IL2 or the myelin oligodendrocyte glycoprotein (MOG fused via an enterokinase site providing linker region to the C terminus of the PHA granule associated protein PhaP, respectively. The hybrid genes were expressed in PHA-accumulating recombinant E. coli. MOG and IL2 fusion proteins were abundantly attached to PHA granules and were identified by MALDI-TOF/MS analysis and N terminal sequencing. A more abundant second fusion protein of either MOG or IL2 resulted from an additional N terminal fusion, which did surprisingly not interfere with attachment to PHA granule. PHA granules displaying either IL2 or MOG were used for FACS using monoclonal anti-IL2 or anti-MOG antibodies conjugated to a fluorescent dye. FACS analysis showed significant and specific binding of respective antibodies. Enterokinase treatment of IL2 displaying PHA granules enabled removal of IL2 as monitored by FACS analysis. Mice were immunized with either MOG or OVA (ovalbumin and the

  8. Production of recombinant insulin-like androgenic gland hormones from three decapod species: In vitro testicular phosphorylation and activation of a newly identified tyrosine kinase receptor from the Eastern spiny lobster, Sagmariasus verreauxi.

    Science.gov (United States)

    Aizen, Joseph; Chandler, Jennifer C; Fitzgibbon, Quinn P; Sagi, Amir; Battaglene, Stephen C; Elizur, Abigail; Ventura, Tomer

    2016-04-01

    In crustaceans the insulin-like androgenic gland hormone (IAG) is responsible for male sexual differentiation. To date, the biochemical pathways through which IAG exerts its effects are poorly understood and could be elucidated through the production of a functional recombinant IAG (rIAG). We have successfully expressed glycosylated, biologically active IAG using the Pichia pastoris yeast expression system. We co-expressed recombinant single-chain precursor molecules consisting of the B and A chains (the mature hormone) tethered by a flexible linker, producing rIAGs of the following commercially important species: Eastern spiny lobster Sagmariasus verreauxi (Sv), redclaw crayfish Cherax quadricarinatus (Cq) and giant freshwater prawn Macrobrachium rosenbergii (Mr). We then tested the biological activity of each, through the ability to increase phosphorylation in the testis; both Sv and Cq rIAGs significantly elevated phosphorylation specific to their species, and in a dose-dependent manner. Mr rIAG was tested on Macrobrachium australiense (Ma), eliciting a similar response. Moreover, using bioinformatics analyses of the de novo assembled spiny lobster transcriptome, we identified a spiny lobster tyrosine kinase insulin receptor (Sv-TKIR). We validated this discovery with a receptor activation assay in COS-7 cells expressing Sv-TKIR, using a reporter SRE-LUC system designed for RTKs, with each of the rIAG proteins acting as the activation ligand. Using recombinant proteins, we aim to develop specific tools to control sexual development through the administration of IAG within the critical sexual differentiation time window. The biologically active rIAGs generated might facilitate commercially feasible solutions for the long sought techniques for sex-change induction and monosex population culture in crustaceans and shed new light on the physiological mode of action of IAG in crustaceans. PMID:26883686

  9. Adlayer structure dependent ultrafast desorption dynamics in carbon monoxide adsorbed on Pd (111)

    Science.gov (United States)

    Hong, Sung-Young; Xu, Pan; Camillone, Nina R.; White, Michael G.; Camillone, Nicholas

    2016-07-01

    We report our ultrafast photoinduced desorption investigation of the coverage dependence of substrate-adsorbate energy transfer in carbon monoxide adlayers on the (111) surface of palladium. As the CO coverage is increased, the adsorption site population shifts from all threefold hollows (up to 0.33 ML), to bridge and near bridge (>0.5 to 0.6 ML) and finally to mixed threefold hollow plus top site (at saturation at 0.75 ML). We show that between 0.24 and 0.75 ML this progression of binding site motifs is accompanied by two remarkable features in the ultrafast photoinduced desorption of the adsorbates: (i) the desorption probability increases roughly two orders magnitude, and (ii) the adsorbate-substrate energy transfer rate observed in two-pulse correlation experiments varies nonmonotonically, having a minimum at intermediate coverages. Simulations using a phenomenological model to describe the adsorbate-substrate energy transfer in terms of frictional coupling indicate that these features are consistent with an adsorption-site dependent electron-mediated energy coupling strength, ηel, that decreases with binding site in the order: three-fold hollow > bridge and near bridge > top site. This weakening of ηel largely counterbalances the decrease in the desorption activation energy that accompanies this progression of adsorption site motifs, moderating what would otherwise be a rise of several orders of magnitude in the desorption probability. Within this framework, the observed energy transfer rate enhancement at saturation coverage is due to interadsorbate energy transfer from the copopulation of molecules bound in three-fold hollows to their top-site neighbors.

  10. Expression of Recombinant Antibodies

    OpenAIRE

    Frenzel, André; Hust, Michael; Schirrmann, Thomas

    2013-01-01

    Recombinant antibodies are highly specific detection probes in research, diagnostics, and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transg...

  11. Dissociation of recombinant prion autocatalysis from infectivity.

    Science.gov (United States)

    Noble, Geoffrey P; Supattapone, Surachai

    2015-01-01

    Within the mammalian prion field, the existence of recombinant prion protein (PrP) conformers with self-replicating (ie. autocatalytic) activity in vitro but little to no infectious activity in vivo challenges a key prediction of the protein-only hypothesis of prion replication--that autocatalytic PrP conformers should be infectious. To understand this dissociation of autocatalysis from infectivity, we recently performed a structural and functional comparison between a highly infectious and non-infectious pair of autocatalytic recombinant PrP conformers derived from the same initial prion strain. (1) We identified restricted, C-terminal structural differences between these 2 conformers and provided evidence that these relatively subtle differences prevent the non-infectious conformer from templating the conversion of native PrP(C) substrates containing a glycosylphosphatidylinositol (GPI) anchor. (1) In this article we discuss a model, consistent with these findings, in which recombinant PrP, lacking post-translational modifications and associated folding constraints, is capable of adopting a wide variety of autocatalytic conformations. Only a subset of these recombinant conformers can be adopted by post-translationally modified native PrP(C), and this subset represents the recombinant conformers with high specific infectivity. We examine this model's implications for the generation of highly infectious recombinant prions and the protein-only hypothesis of prion replication.

  12. Adsorption-Desorption Characteristics of Chlorimuron-Ethyl in Soils

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The adsorption-desorption characteristics of chlorimuron-ethyl in soils were investigated to provide the basic data for evaluating the safety in field and the risk to water resource. The adsorption-desorption experiment was conducted by the batch equilibration and HPLC techniques; furthermore, data were analyzed with 5 mathematic models to describe the characteristics and mechanism of adsorption-desorption and translocation of the herbicide in soils. The results showed that the adsorption-desorption isotherms of chlorimuron-ethyl fitted for the Freundlich model well, and the physical reaction presents the main contribution during the adsorption-desorption process. The adsorption values (Kads-f) of chlorimuron-ethyl in 8 types of soil ranged from 0.798 to 6.891. The isotherms of 2# (Jiangxi clay) and 3# (Jiangxi sand loam)soils belong to the S-type curve, while the isotherms of another 6 type soils belong to the L-type isotherm. The results of desorption indicated that the hysteresis phenomena appeared during the desorption process, and the hysteresis coefficients(H) of the herbicides in 8 soils varied from 0.259-0.980. Furthermore, Kads-f and desorption values (Kdes-f) increased with the OM (%) and the clay content increasing, while the values decreased with the soils pH increasing. The H values decreased with the OM and the clay content increasing, and increased with the soils pH increasing. It can be concluded that the low adsorption abilities of chlorimuron-ethyl in test soils and un-reversible adsorption existed in the process, which will induce the great translocation of the herbicide after application in field. It can be transported to ground or groundwater causing risk to environments. The physical and chemical properties of soils, including the OM, the clay content, and the pH of soil were the dominating factors during the adsorption-desorption.

  13. Production of enzymatically active recombinant full-length barley high pI alpha-glucosidase of glycoside family 31 by high cell-density fermentation of Pichia pastoris and affinity purification

    DEFF Research Database (Denmark)

    Næsted, Henrik; Kramhøft, Birte; Lok, F.;

    2006-01-01

    Recombinant barley high pI alpha-glucosidase was produced by high cell-density fermentation of Pichia pastoris expressing the cloned full-length gene. The gene was amplified from a genomic clone and exons (coding regions) were assembled by overlap PCR. The resulting cDNA was expressed under control...... of the alcohol oxidase 1 promoter using methanol induction of P. pastoris fermentation in a Biostat B 5 L reactor. Forty-two milligrams a-glucosidase was purified from 3.5 L culture in four steps applying an N-terminal hexa-histidine tag. The apparent molecular mass of the recombinant alpha-glucosidase was 100 k......Da compared to 92 kDa of the native barley enzyme. The secreted recombinant enzyme was highly stabile during the 5-day fermentation and had significantly superior specific activity of the enzyme purified previously from barley malt. The kinetic parameters K-m, V-max, and k(cat) were determined to 1.7 mM, 139...

  14. Immune Response to Recombinant Capsid Proteins of Adenovirus in Humans: Antifiber and Anti-Penton Base Antibodies Have a Synergistic Effect on Neutralizing Activity

    OpenAIRE

    Gahéry-Ségard, Hanne; Farace, Françoise; Godfrin, Dominique; Gaston, Jesintha; Lengagne, Renée; Tursz, Thomas; Boulanger, Pierre; Guillet, Jean-Gérard

    1998-01-01

    Replication-deficient adenovirus used in humans for gene therapy induces a strong immune response to the vector, resulting in transient recombinant protein expression and the blocking of gene transfer upon a second administration. Therefore, in this study we examined in detail the capsid-specific humoral immune response in sera of patients with lung cancer who had been given one dose of a replication-defective adenovirus. We analyzed the immune response to the three major components of the vi...

  15. Thermal desorption of Au from W(001) surface

    CERN Document Server

    Blaszczyszyn, R; Godowski, P J

    2002-01-01

    Adsorption of Au on W(001) at 450 K up to multilayer structures was investigated. Temperature programmed desorption technique was used in determination of coverage dependent desorption energy (region up to one monolayer). Results were discussed in terms of competitive interactions of Au-Au and Au-W atoms. Simple procedure for prediction of faceting behavior on the interface, basing on the desorption data, was postulated. It was deduced that the Au/W(001) interface should not show faceting tendency after thermal treatment. (author)

  16. Thermal Desorption of Au from W(001) Surface

    Science.gov (United States)

    Błaszczyszyn, R.; Chrzanowski, J.; Godowski, P. J.

    2000-12-01

    Adsorption of Au on W(001) at 450 K up to multilayer structures was investigated. Temperature programmed desorption technique was used in determination of coverage dependent desorption energy (region up to one monolayer). Results were discussed in terms of competitive interactions of Au--Au and Au--W atoms. Simple procedure for prediction of faceting behavior on the interface, basing on the desorption data, was postulated. It was deduced that the Au/W(001) interface should not show faceting tendency after thermal treatment.

  17. Workshop on Radio Recombination Lines

    CERN Document Server

    1980-01-01

    Since their first detection 15 years ago, radio recombination lines from several elements have been observed in a wide variety of objects including HII regions, planetary nebulae, molecular clouds, the diffuse interstellar medium, and recently, other galaxies. The observations span almost the entire range from 0.1 to 100 GHz, and employ both single­ djsh and aperture synthesis techniques. The theory of radio recombination lines has also advanced strongly, to the point where it is perhaps one of the best-understood in astro­ physics. In a parallel development, it has become possible over the last decade to study these same highly-excited atoms in the laboratory; this work provides further confirmation of the theoretical framework. However there has been continuing controversy over the astrophysical interpre­ tation of radio recombination line observations, especially regarding the role of stimulated emission. A workshop was held in Ottawa on 24-25 August, 1979, bringing together many of the active scientist...

  18. Adsorption and desorption kinetics of carbofuran in acid soils.

    Science.gov (United States)

    Bermúdez-Couso, Alipio; Fernández-Calviño, David; Pateiro-Moure, Miriam; Nóvoa-Muñoz, Juan Carlos; Simal-Gándara, Jesús; Arias-Estévez, Manuel

    2011-06-15

    Carbofuran adsorption and desorption were investigated in batch and stirred flow chamber (SFC) tests. The carbofuran adsorption capacity of the soils was found to be low and strongly dependent on their clay and organic carbon contents. Carbofuran sorption was due mainly (>80%) to fast adsorption processes governed by intraparticle diffusion. The adsorption kinetic constant for the pesticide ranged from 0.047 to 0.195 min(-1) and was highly correlated with constant n in the Freundlich equation (r=0.965, Pcarbofuran desorption to be highly variable and negatively correlated with eCEC and the clay content. The SFC tests showed that soil organic carbon (C) plays a key role in the irreversibility of carbofuran adsorption. Carbofuran desorption increased rapidly at C contents below 4%. The desorption kinetic constant for the compound (0.086-0.195 min(-1)) was generally higher than its adsorption kinetic constant; therefore, carbofuran is more rapidly desorbed than it is adsorbed in soil.

  19. Regulation of Meiotic Recombination

    Energy Technology Data Exchange (ETDEWEB)

    Gregory p. Copenhaver

    2011-11-09

    Meiotic recombination results in the heritable rearrangement of DNA, primarily through reciprocal exchange between homologous chromosome or gene conversion. In plants these events are critical for ensuring proper chromosome segregation, facilitating DNA repair and providing a basis for genetic diversity. Understanding this fundamental biological mechanism will directly facilitate trait mapping, conventional plant breeding, and development of genetic engineering techniques that will help support the responsible production and conversion of renewable resources for fuels, chemicals, and the conservation of energy (1-3). Substantial progress has been made in understanding the basal recombination machinery, much of which is conserved in organisms as diverse as yeast, plants and mammals (4, 5). Significantly less is known about the factors that regulate how often and where that basal machinery acts on higher eukaryotic chromosomes. One important mechanism for regulating the frequency and distribution of meiotic recombination is crossover interference - or the ability of one recombination event to influence nearby events. The MUS81 gene is thought to play an important role in regulating the influence of interference on crossing over. The immediate goals of this project are to use reverse genetics to identify mutants in two putative MUS81 homologs in the model plant Arabidopsis thaliana, characterize those mutants and initiate a novel forward genetic screen for additional regulators of meiotic recombination. The long-term goal of the project is to understand how meiotic recombination is regulated in higher eukaryotes with an emphasis on the molecular basis of crossover interference. The ability to monitor recombination in all four meiotic products (tetrad analysis) has been a powerful tool in the arsenal of yeast geneticists. Previously, the qrt mutant of Arabidopsis, which causes the four pollen products of male meiosis to remain attached, was developed as a facile system

  20. 微波辐照再生载硫活性炭的机理及其动力学%Desorption mechanism and kinetics of SO2 loaded activated carbon by microwave irradiation

    Institute of Scientific and Technical Information of China (English)

    张立强; 蒋海涛; 李兵; 陈磊; 马春元

    2012-01-01

    The regeneration of activated carbon after chemically adsorbing SO2 was carried out by using a microwave device. The mechanism and kinetics of the regeneration of SO2 loaded activated carbon were revealed through analysis of the regeneration products. The results show that in the microwave field, there is a rapid increase in temperature of activated carbon and the final temperature is relatively stable. SO2, CO2 and CO are evolved during regeneration, which indicates that there are reactions between H2SO4 and C. The regeneration reactions are carried out before the peak of SO2, and after that a portion of CO2 and CO are owing to the decomposition of oxygen functional groups which is formed on the surface of activated carbon in the process of adsorption of SO2. The order of activated carbon regenera- tion reaction in the main of regeneration reaction is 1.55, which is independent of microwave input power. The reaction rate constant increases with microwave input power increase. According to Arrhenius equation, the apparent activation energy is 46.0 kJ/mol and the pre-exponential factor is 7. 357 s-1.%在微波再生试验台上进行化学吸附SO2后活性炭的再生实验,通过再生产物的分析揭示再生机理并进行动力学分析。结果表明:微波场中活性炭升温速率快,而且终温较为稳定;载硫活性炭微波再生出口气体成分有SO2,CO2,CO等气体,再生反应的本质是H2SO4与C的反应;再生气体中SO2峰值出现之前,主要发生再生反应,峰值之后,再生气体中部分CO2和CO来源于吸附过程中形成的活性炭表面含氧官能团的分解。再生反应的主区域内反应级数为1.55级,与微波功率无关;随着微波功率的增加,反应速率常数逐渐增加。由Arrhenius方程得出再生反应的表观活化能Ea为46.0 kJ/mol,指前因子为7.357 s-1。

  1. The efficacy of recombinant human activated protein C (rhAPC) vs antithrombin III (at III) vs heparin, in the healing process of partial-thickness burns: a comparative study

    Science.gov (United States)

    Kritikos, O.; Tsagarakis, M.; Tsoutsos, D.; Kittas, C.; Gorgoulis, V.; Papalois, A.; Giannopoulos, A.; Kakiopoulos, G.; Papadopoulos, O.

    2012-01-01

    Summary This is an experimental study regarding the positive effect of recombinant human activated protein C (rhAPC) in the healing process of partial-thickness burns, in comparison to antithrombin III and heparin. On a porcine model we induced superficial partial-thickness and deep partial-thickness burns and performed intravenous administration of the elements of study during the first 48 h. The progress of the condition of the injured tissues was evaluated by histopathological examination at specific time intervals. The results showed an improved healing response of the specimens treated with rhAPC compared to those treated with antithrombin III, heparin, and placebo. PMID:23233823

  2. Sorption, Desorption and Diffusion of Tc Under Anaerobic Conditions

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The sorption and diffusion of Tc on granite under anaerobic conditions were investigated. Influencesof pH values, ferrous minerals(reduced iron powder or magnetite), bentonite, concentration of cations andanion (Fe3+, Fe2+ and CO32-) on the distribution coefficient, Kd, were studied. The sorption mechanism of99Tc on granite was analyzed by the desorption method of adding H2O2 into desorption solvent. Based on

  3. Study on hydrogen absorption/desorption properties of uranium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hiroshi; Yamaguchi, Kenji; Yamawaki, Michio [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.

    1996-10-01

    Hydrogen absorption/desorption properties of two U-Mn intermetallic compounds, U{sub 6}Mn and UMn{sub 2}, were investigated. U{sub 6}Mn absorbed hydrogen and the hydrogen desorption pressure of U{sub 6}Mn obtained from this experiment was higher than that of U, which was considered to be the effect of alloying, whereas UMn{sub 2} was not observed to absorb hydrogen up to 50 atm at room temperature. (author)

  4. Promoting and avoiding recombination: contrasting activities of the Escherichia coli RuvABC Holliday junction resolvase and RecG DNA translocase.

    Science.gov (United States)

    Zhang, Jing; Mahdi, Akeel A; Briggs, Geoffrey S; Lloyd, Robert G

    2010-05-01

    RuvABC and RecG are thought to provide alternative pathways for the late stages of recombination in Escherichia coli. Inactivation of both blocks the recovery of recombinants in genetic crosses. RuvABC resolves Holliday junctions, with RuvAB driving branch migration and RuvC catalyzing junction cleavage. RecG also drives branch migration, but no nuclease has been identified that might act with RecG to cleave junctions, apart from RusA, which is not normally expressed. We searched for an alternative nuclease using a synthetic lethality assay to screen for mutations causing inviability in the absence of RuvC, on the premise that a strain without any ability to cut junctions might be inviable. All the mutations identified mapped to polA, dam, or uvrD. None of these genes encodes a nuclease that cleaves Holliday junctions. Probing the reason for the inviability using the RusA Holliday junction resolvase provided strong evidence in each case that the RecG pathway is very ineffective at removing junctions and indicated that a nuclease component most probably does not exist. It also revealed new suppressors of recG, which were located to the ssb gene. Taken together with the results from the synthetic lethality assays, the properties of the mutant SSB proteins provide evidence that, rather than promoting recombination, a major function of RecG is to curb potentially pathological replication initiated via PriA protein at sites remote from oriC. PMID:20157002

  5. Sorption and desorption of 1,4-dichlorobenzene on peat

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Sorption and desorption of 1,4-dichlorobenzene (DCB) on peat (>92% organic matter)display large-scale hysteresis and nonlinearity. The magnitude of desorption hysteresis decreases in the order: untreated Pahokee peat (P)>acid treated peat (FP)>humin (TP). The desorption percentages are lower than 28% of the sorbed 1, 4-DCB after desorbing for 6 days. The sorption and desorption isotherms are well fitted to Freundlich equation, whose parameter 1/n ranges from 0.055 to 0.527. Moreover, the parameter 1/n of the desorption isotherm is significantly lower than that of the sorption isotherm, but the parameter IogK increases on contrary to 1/n. The desorption isotherms are very well fitted to Langmuir equation, whose Qm decreases in the order: TP>FP>P.The apparent partition coefficients (Kp) increase with increasing sorption time or decreasing aqueous equilibrium concentration of DCB. And Kp of P is significantly higher than that of FP or TP.

  6. Laser-induced thermal desorption of aniline from silica surfaces

    Science.gov (United States)

    Voumard, Pierre; Zenobi, Renato

    1995-10-01

    A complete study on the energy partitioning upon laser-induced thermal desorption of aniline from silica surfaces was undertaken. The measurements include characterization of the aniline-quartz adsorption system using temperature-programmed desorption, the extrapolation of quasiequilibrium desorption temperatures to the regime of laser heating rates on the order of 109-1010 K/s by computational means, measurement of the kinetic energy distributions of desorbing aniline using a pump-probe method, and the determination of internal energies with resonance-enhanced multiphoton ionization spectroscopy. The measurements are compared to calculations of the surface temperature rise and the resulting desorption rates, based on a finite-difference mathematical description of pulsed laser heating. While the surface temperature of laser-heated silica reaches about 600-700 K at the time of desorption, the translational temperature of laser-desorbed aniline was measured to be Tkin=420±60 K, Tvib was 360±60 K, and Trot was 350±100 K. These results are discussed using different models for laser-induced thermal desorption from surfaces.

  7. Calcium lignosulfonate adsorption and desorption on Berea sandstone.

    Science.gov (United States)

    Grigg, Reid B; Bai, Baojun

    2004-11-01

    This paper describes adsorption and desorption studies carried out with calcium lignosulfonate (CLS) on Berea sandstone. Circulation experiments were performed to determine CLS adsorption isotherms and the effects of CLS concentration, temperature, salinity, brine hardness, and injection rate on adsorption density. Flow-through experiments were performed to assess the reversibility of CLS adsorption and the influence of postflush rate, brine concentration, brine hardness, brine pH, and temperature on the desorption process. Results indicate that CLS adsorption isotherms on Berea sandstone follow the Freundlich isotherm law. The results presented in this paper on the effects of CLS adsorption and desorption on Berea sandstone show that: (1) increasing CLS concentration and salinity increases CLS adsorption density; (2) increasing temperature will decrease adsorption density; (3) increasing injection rate of CLS solution will slightly decrease CLS adsorption density; (4) postflush rate and salinity of brine have a large impact on the CLS desorption process; (5) the adsorption and desorption process are not completely reversible; and (5) temperature and pH of the postflush brine have little effect on desorption.

  8. Water desorption of cassava starch granules: A study based on thermogravimetric analysis of aqueous suspensions and humid powders.

    Science.gov (United States)

    Ayala Valencia, Germán; Djabourov, Madeleine; do Amaral Sobral, Paulo José

    2016-08-20

    This work reports on water desorption from cassava starch in relation with the structure and conditioning of granules in suspensions or after equilibration in desiccators. The experimental work is performed by thermogravimetric analysis with isothermal and non-isothermal protocols and interpreted to derive the activation energies and desorption frequencies according to the humidity range with no adjustable parameter. The analysis points out the different types of water interacting with the starch granules and relates the drying coefficients to their microscopic structure. The work helps clarifying contradictory and partial results from the literature.

  9. Conceptual design for a full-scale VAC*TRAX vacuum thermal desorption unit. Final report, September 1992--December 1995

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, C.R.

    1996-04-01

    Rust Federal Services is pleased to present this topical report on the results of our Phase II conceptual design work of the PRDA VAC*TRAX{sup SM} mobile vacuum thermal desorption technology demonstration program. Through the present Phase II conceptual design activities, Rust has developed an equipment design and permitting strategy that retains the flexibility of a mobile treatment system with the long term value and ease of access of a central facility. The process is designed to remove volatile matter from solid matrices by thermal desorption. The system is also designed with superior emission controls, making it an ideal system for the treatment of radioactive wastes.

  10. Water desorption of cassava starch granules: A study based on thermogravimetric analysis of aqueous suspensions and humid powders.

    Science.gov (United States)

    Ayala Valencia, Germán; Djabourov, Madeleine; do Amaral Sobral, Paulo José

    2016-08-20

    This work reports on water desorption from cassava starch in relation with the structure and conditioning of granules in suspensions or after equilibration in desiccators. The experimental work is performed by thermogravimetric analysis with isothermal and non-isothermal protocols and interpreted to derive the activation energies and desorption frequencies according to the humidity range with no adjustable parameter. The analysis points out the different types of water interacting with the starch granules and relates the drying coefficients to their microscopic structure. The work helps clarifying contradictory and partial results from the literature. PMID:27178961

  11. The Detection of Genotıxic Activity of The Deltamethrin and Permethrin by Somatic Mutation and Recombination Test With Drosophila Melanogaster

    Directory of Open Access Journals (Sweden)

    F. Azize BUDAK

    2005-06-01

    Full Text Available In this study, different doses of deltamethrin from pyretyroide insecticides and permethrine from organophosphate insecticides have been analysied for their genotoxic effects by somatic mutation and recombination test (SMART in Drosophila melanogaster. Lethal doses of chemicals used were determined. Trans-heterozygous larvae for two genetic markers mwh and flr3 were evaluated for 25 ppm, 50 ppm and 75 ppm concentrations of the insecticides. A possitive correlation was observed among total mutations, the number of wings having mutations and percentage survival. Mutations observed were classified according to their size and type per wing and the dataevaluated by statistical analysis. Deltamethrin was found more toxic and mutagenic than permethrine.

  12. 重组活化人凝血因子Ⅶ在肝脏移植术中应用%Application of recombinant activated factor Ⅶ in liver transplantation

    Institute of Scientific and Technical Information of China (English)

    李宏; 邓迺封

    2006-01-01

    重组活化人凝血因子Ⅶ(recombinant factor Ⅶa,rFⅦa),是一种新型止血药,最初用于治疗存在有因子Ⅷ(FⅧ)和因子IX(FIX)抗体(抑制物)的先天性血友病和继发性血友病患者的自发性或手术性出血。目前,已证实该药对控制多种临床出血情况是有益的。

  13. 石斑鱼β-防御素的酵母表达及其产物抗菌活性分析%THE YEAST EXPRESSION OF GROUPER β-DEFENSIN AND ANTIBACTERIAL ACTIVITY OF THE RECOMBINANT PROTEIN

    Institute of Scientific and Technical Information of China (English)

    金俊琰; 周莉; 桂建芳

    2011-01-01

    防御素是一类阳离子抗菌肽.研究从石斑鱼垂体SMART cDNA文库中扩增出129 bp石斑鱼β-防御素成熟肽序列,将其克隆到毕赤酵母表达载体pPCIZαA中,构建了石斑鱼β-防御素的真核表达载体,电击转化毕赤酵母GS115.Western Blot分析表明石斑鱼β-防御素在酵母菌中获得了表达.体外抗菌实验表明纯化的重组蛋白具有抑制大肠杆菌以及嗜水气单胞菌的作用,但是对革兰氏阳性菌,如金黄色葡萄球菌和藤黄微球菌的生长没有抑制作用.实验结果表明酵母表达的石斑鱼β-防御素能够特异地抑制革兰氏阴性菌的生长.%Defensin, a small cationic peptide, is an antimicrobial peptide, exhibit broad-spectrum antibacterial activity. They spread widely in plants, invertebrate and vertebrate animals, which can rapidly kill bacteria, fungi and viruses etc. Bacteria and viruses limited the production of grouper (Epinephelus coioides). In this study, we cloned grouper P-defensin open reading frame, to express in the Pichia pastoris, and detect the bioactive of recombinant protein against bacteria. First, grouper P-defensin cDNA was amplified by polymerase chain reaction (PCR) from pituitary cDNA library of a protogynous hermaphroditic orange-spotted grouper. The 129 bp DNA fragment encoding mature grouper P-defensin peptide was subcloned into vector PMD18-T, then inserted into the yeast expression vector pPClZaA and transfected into Pichia pastoris GS115 expression host by electroporation. The genome of Pichia pastoris clone was extracted as template for screened the positive clone by using PCR. After grouper p-defensin was secreted by GS 115 by small-scale culture, the recombinant grouper P-defensin was induced by methanol for large scale. The supernatant was collected in 24h, 48h and 72h post induction for the recombinant protein detection. Subsequently, the grouper p-defensin peptide was detected in the supernatant of transfected yeast by Western Blot

  14. Molecular Hydrogen Formation on Low Temperature Surfaces in Temperature Programmed Desorption Experiments

    CERN Document Server

    Vidali, G; Li, L; Roser, J; Manico, G; Mehl, R; Lederhendler, A; Perets, H B; Brucato, J R; Biham, O

    2007-01-01

    The study of the formation of molecular hydrogen on low temperature surfaces is of interest both because it allows to explore elementary steps in the heterogeneous catalysis of a simple molecule and because of the applications in astrochemistry. Here we report results of experiments of molecular hydrogen formation on amorphous silicate surfaces using temperature-programmed desorption (TPD). In these experiments beams of H and D atoms are irradiated on the surface of an amorphous silicate sample. The desorption rate of HD molecules is monitored using a mass spectrometer during a subsequent TPD run. The results are analyzed using rate equations and the activation energies of the processes leading to molecular hydrogen formation are obtained from the TPD data. We show that a model based on a single isotope provides the correct results for the activation energies for diffusion and desorption of H atoms. These results can thus be used to evaluate the formation rate of H_2 on dust grains under the actual conditions...

  15. Recombination in ionized gases

    International Nuclear Information System (INIS)

    In this paper it is shown how capture-stabilized methodology (both macroscopic and microscopic) can provide a generic basis for a unified treatment of all of the above recombination mechanisms. A new semiclassical theory of dissociative recombination is also presented in an effort to gain further insight into the physics not included in the first-order treatment and difficult to extract from numerical quantal treatments based on configuration mixing and on multichannel quantum defect theory. A simple analytical expression more accurate than the standard first-order result is obtained for the cross section σ and rate coefficient α. (author)

  16. Temperature dependence of CO desorption kinetics at a novel Pt-on-Au/C PEM fuel cell anode

    DEFF Research Database (Denmark)

    Pitois, A.; Pilenga, A.; Pfrang, A.;

    2010-01-01

    -modified catalysts, the interactions between underlayer and overlayer materials are worthy of consideration, since they can significantly modify the intrinsic properties of the active sites. The kinetics of the CO desorption process have been discussed with regard to the CO tolerance issue at the PEM fuel cell anode....

  17. Electrical Characteristics and Desorption Kinetics of Soil Boron

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The status and activities of boron in soils were studied by the approach of electro-ultrafiltration (EUF). The samples of soils, including brown-red soil and calcareous alluvial soil, were collected from Hubei Province of China. The soil samples were incubated in saturated water and then their nutrients were ultrafiltrated with EUF equipment. Filtration and extraction were conducted in accordance with routine process, but fractions in anode and cathode were all collected. Analyses of B, K+, Mg2+, Ca2+, C1- and pH in fractions supposed that boron existed not only in a simple form of borate but also in ion-pair with cations partly in acidic soil,and borate was the primary form existing in the calcareous soil. In studying desorption kinetics with EUF,the boron content of Fractions 2~6 was accumulated, and the accumulative quantities were fit to time factors in three kinetic equations: the zero-order, first-order, and arabolic diffusion equations. Fit degree of the parabolic diffusion equation was the best, followed by the zero-order quation, and the first-order equation was the worst.

  18. Purification and biological activity of recombinant thymosin alpha 1%重组胸腺素α1的分离纯化和活性测定

    Institute of Scientific and Technical Information of China (English)

    石继红; 张英起; 赵宁; 颜真; 韩苇; 赵永同

    2001-01-01

    目的 利用融合表达载体pThioHisA的重组质粒pThioHisA-Tα1④, 转化大肠杆菌TOP10得到的工程菌,来分离纯化表达的胸腺素α1(thymosin alpha 1,T α1). 方法 将高效表达融合蛋白 的工程菌用细胞破碎器裂解,经80℃热处理,离心上清采用Q-Sepharose FF阴离子交换色谱纯化融合蛋白. 融合蛋白经CNBr裂 解后用常压离子交换色谱纯化Tα1单体. 应用SDS-PAGE,2L-Tricine-SDS-PAGE和HPLC进行鉴定. 结果 [ HTSS SDS-PAGE分析表明菌体表达的融合蛋白占菌体总蛋白的400 g*kg-1. 经2L-Tricine-SDS-PAGE分析证实,融合蛋白可裂 解出Tα1单体,裂解物经简单的离子色谱可以纯化出Tα1单体,HPLC鉴定纯化出的Tα1纯度可达950 g*kg-1以上. 利用3H-TdR进行的生物活性测定表明,在致有丝分裂原ConA存在的条件下,融合蛋白和Tα1单体均具有刺激小鼠脾淋巴细胞 分裂增殖的能力,与化学合成的Tα1相比具有相似的生物活性. 结论 该方法是分离纯化Tα1 简便易行,经济有效的方法;同时也为Tα1的分离纯化和大规模的开发生产奠定了基础.%AIM To purify and prepare thymosin alpha 1 (Tα 1). METHODS The engineering bacteria TOP10 including recombinant plasmid of a fusion expression vector pThioHisA with the tandem Tα 1 gene of 4 repeats (Tα1④) was used. after bacter ia lysated by Bionee Cell Disruoter, the lysate was incubat ed in the temperature of 80℃ for 10 minutes, and cooled quickly. By Q-Sepharose Fast Flow chromatography, the fusio n protein was purified from the supernatant of the lysate. At the concentrion of 0.5 mol*L-1 CNBr cleavage of the fusion protein in 700 mL*L-1 formic acid, Tα1 was purified by ion exchange methods of SP-Sepharose Fast Flow and Q-Sepharose Fast Flow. T hese were identified by SDS-PAGE, 2L-Tricine-SDS-PAGE and HPLC. RESULTS SDS-PAGE analysis showed an induced expression fusion protein band which consititued 400 g

  19. Recombinant DNA for Teachers.

    Science.gov (United States)

    Duvall, James G., III

    1992-01-01

    A science teacher describes his experience at a workshop to learn to teach the Cold Spring Harbor DNA Science Laboratory Protocols. These protocols lead students through processes for taking E. coli cells and transforming them into a new antibiotic resistant strain. The workshop featured discussions of the role of DNA recombinant technology in…

  20. Recombineering Pseudomonas syringae

    Science.gov (United States)

    Here we report the identification of functions that promote genomic recombination of linear DNA introduced into Pseudomonas cells by electroporation. The genes encoding these functions were identified in Pseudomonas syringae pv. syringae B728a based on similarity to the lambda Red Exo/Beta and RecE...

  1. Adsorption and desorption dynamics of citric acid anions in soil

    KAUST Repository

    Oburger, E.

    2011-07-26

    The functional role of organic acid anions in soil has been intensively investigated, with special focus on (i) microbial respiration and soil carbon dynamics, (ii) nutrient solubilization or (iii) metal detoxification and reduction of plant metal uptake. Little is known about the interaction dynamics of organic acid anions with the soil matrix and the potential impact of adsorption and desorption processes on the functional significance of these effects. The aim of this study was to characterize experimentally the adsorption and desorption dynamics of organic acid anions in five agricultural soils differing in iron and aluminium oxide contents and using citrate as a model carboxylate. Results showed that both adsorption and desorption processes were fast in all soils, reaching a steady state within approximately 1 hour. However, for a given total soil citrate concentration (ct) the steady state was critically dependent on the starting conditions of the experiment, whether most of the citrate was initially present in solution (cl) or held on the solid phase (cs). Specifically, desorption-led processes resulted in significantly smaller steady-state solution concentrations than adsorption-led processes, indicating that hysteresis occurred. As it is not possible to distinguish between different adsorption and desorption pools in soil experimentally, a new dynamic hysteresis model that relies only on measured soil solution concentrations was developed. The model satisfactorily explained experimental data and was able to predict dynamic adsorption and desorption behaviour. To demonstrate its use, we applied the model to two relevant situations involving exudation and microbial degradation. The study highlighted the complex nature of citrate adsorption and desorption dynamics in soil. We conclude that existing models need to incorporate both temporal and hysteresis components to describe realistically the role and fate of organic acids in soil processes. © 2011 The

  2. Data on the evolutionary history of the V(DJ recombination-activating protein 1 – RAG1 coupled with sequence and variant analyses

    Directory of Open Access Journals (Sweden)

    Abhishek Kumar

    2016-09-01

    Full Text Available RAG1 protein is one of the key component of RAG complex regulating the V(DJ recombination. There are only few studies for RAG1 concerning evolutionary history, detailed sequence and mutational hotspots. Herein, we present out datasets used for the recent comprehensive study of RAG1 based on sequence, phylogenetic and genetic variant analyses (Kumar et al., 2015 [1]. Protein sequence alignment helped in characterizing the conserved domains and regions of RAG1. It also aided in unraveling ancestral RAG1 in the sea urchin. Human genetic variant analyses revealed 751 mutational hotspots, located both in the coding and the non-coding regions. For further analysis and discussion, see (Kumar et al., 2015 [1].

  3. Cultured Mast Cells from Patients with Asthma and Controls Respond with Similar Sensitivity to Recombinant Der P2-Induced, IgE-Mediated Activation

    DEFF Research Database (Denmark)

    Krohn, I K; Sverrild, A; Lund, G;

    2013-01-01

    The function of cultured mast cells may depend on genetic or environmental influence on the stem cell donor. This study investigates whether asthma or atopy in the donor influenced the growth and sensitivity of mast cells cultured from patients with asthma and healthy controls under identical...... conditions. Mast cells were cultured from peripheral blood from twelve patients with an objectively confirmed asthma diagnosis and eight healthy subjects. During the last 2 weeks of culture, mast cells were incubated with IL-4 and 80 kU/l recombinant human IgE containing two clones (7% + 7%) specific...... CD63 median fluorescence intensity was 20 456 ± 1640 (SE) for patients with asthma and 22,275 ± 1971 (SE) for controls (ns). The fraction of CD63 positive cells was 54.4% in patients with asthma and 48.4% in controls (ns). The allergen concentration inducing 50% of the maximal CD63 response...

  4. Surface reconstruction and thermal desorption: {O}/{Ag(110) } an experimental study

    Science.gov (United States)

    Canepa, M.; Salvietti, M.; Traverso, M.; Mattera, L.

    1995-07-01

    We have studied the associative desorption of oxygen from well-defined O( n×1)Ag(110) phases ( n ranging from 8 to 2) by thermal desorption mass spectrometry. Desorption peak profiles have been compared with calculations based on a lattice-gas model [V.P. Zhdanov, Surf. Sci. 277 (1992) 155] which takes into account the missing-row reconstruction of the substrate and adsorbate-adsorbate interactions along independent OAgO rows. The model works well at low coverage accurately reproducing the peak profiles. For the O(8 × 1), O(6 × 1) and O(4 × 1) phases, assuming a value of v = 10 15 s -1 for the pre-factor, values of ≈ 39 kcal/mol for the activation energy and ≈ -2.5 kcal/mol for the OO effective oxygen-oxygen interaction along OAgO rows are obtained. At high coverage the assumption of independence of OAgO chains is no longer valid and repulsive interactions perpendicularly to the chains have to be taken into account.

  5. Optical breathing of nano-porous antireflective coatings through adsorption and desorption of water.

    Science.gov (United States)

    Nielsen, Karsten H; Kittel, Thomas; Wondraczek, Katrin; Wondraczek, Lothar

    2014-10-13

    We report on the direct consequences of reversible water adsorption on the optical performance of silica-based nanoporous antireflective (AR) coatings as they are applied on glass in photovoltaic and solar thermal energy conversion systems. In situ UV-VIS transmission spectroscopy and path length measurements through high-resolution interferometric microscopy were conducted on model films during exposure to different levels of humidity and temperature. We show that water adsorption in the pores of the film results in a notable increase of the effective refractive index of the coating. As a consequence, the AR effect is strongly reduced. The temperature regime in which the major part of the water can be driven-out rapidly lies in the range of 55°C and 135°C. Such thermal desorption was found to increase the overall transmission of a coated glass by ~ 1%-point. As the activation energy of isothermal desorption, we find a value of about 18 kJ/mol. Within the experimental range of our data, the sorption and desorption process is fully reversible, resulting in optical breathing of the film. Nanoporous AR films with closed pore structure or high hydrophobicity may be of advantage for maintaining AR performance under air exposure.

  6. Rabbits immunized with Epstein-Barr virus gH/gL or gB recombinant proteins elicit higher serum virus neutralizing activity than gp350.

    Science.gov (United States)

    Cui, Xinle; Cao, Zhouhong; Chen, Quanyi; Arjunaraja, Swadhinya; Snow, Andrew L; Snapper, Clifford M

    2016-07-25

    Epstein-Barr virus (EBV) is the primary cause of infectious mononucleosis and has been strongly implicated in the etiology of multiple epithelial and lymphoid cancers, such as nasopharyngeal carcinoma, gastric carcinoma, Hodgkin lymphoma, Burkitt lymphoma, non-Hodgkin lymphoma and post-transplant lymphoproliferative disorder. There is currently no licensed prophylactic vaccine for EBV. Most efforts to develop prophylactic vaccines have focused on EBV gp350, which binds to CD21/CD35 to gain entry into B cells, and is a major target of serum neutralizing antibody in EBV seropositive humans. However, a recombinant monomeric gp350 protein failed to prevent EBV infection in a phase II clinical trial. Thus, alternative or additional target antigens may be necessary for a successful prophylactic vaccine. EBV gH/gL and gB proteins coordinately mediate EBV fusion and entry into B cells and epithelial cells, strongly suggesting that vaccination with these proteins might elicit antibodies that will prevent EBV infection. We produced recombinant trimeric and monomeric EBV gH/gL heterodimeric proteins and a trimeric EBV gB protein, in addition to tetrameric and monomeric gp350(1-470) proteins, in Chinese hamster ovary cells. We demonstrated that vaccination of rabbits with trimeric and monomeric gH/gL, trimeric gB, and tetrameric gp350(1-470) induced serum EBV-neutralizing titers, using cultured human B cells, that were >100-fold, 20-fold, 18-fold, and 4-fold higher, respectively, than monomeric gp350(1-470). These data strongly suggest a role for testing EBV gH/gL and EBV gB in a future prophylactic vaccine to prevent EBV infection of B cells, as well as epithelial cells. PMID:27291087

  7. Cesium sorption and desorption behavior of clay minerals

    International Nuclear Information System (INIS)

    Cesium sorption and desorption of clay minerals (montmorillonite, beidellite, nontronite, weathered biotite, rectorite and illite) were investigated by consecutive sorption-desorption (CSD) experiments. In batch sorption experiment, two solutions with different Cs concentration 10-3 and 10-7 mol/L) were used. In batch desorption experiments, Cs sorbed samples in sorption experiments were treated 5 times with 1 mol/L ammonium acetate solution. In the case of CSD experiments using 10-3 mol/L Cs solution, the exchangeable cations (Na, Ca, and K) in the clay samples affected to the sorption ratio of Cs, and this effect depended on the type of clay mineral. The desorption ratios of untreated, Na-exchanged and Ca-exchanged weathered biotite ranged from 23 to 33%, while that of other samples was over 80%. In the case of CSD experiments using 10-7 mol/L Cs solution, the sorption ratio of montmorillonite was smaller than that of the other clay samples. In desorption experiments, more than 10-9 mol sorbed Cs remained in 1.0 g of the sample after 5 extraction times. These results indicate that all examined clay samples are able to strongly adsorb Cs with a capacity of more than 10-9 mol/g. (author)

  8. Sorption-desorption behavior of polybrominated diphenyl ethers in soils

    International Nuclear Information System (INIS)

    Polybrominated diphenyl ethers (PBDEs) are flame retardants that are commonly found in commercial and household products. These compounds are considered persistent organic pollutants. In this study, we used 4,4'-dibromodiphenyl ether (BDE-15) as a model compound to elucidate the sorption and desorption behavior of PBDEs in soils. The organic carbon-normalized sorption coefficient (KOC) of BDE-15 was more than three times higher for humin than for bulk soils. However, pronounced desorption hysteresis was obtained mainly for bulk soils. For humin, increasing concentration of sorbed BDE-15 resulted in decreased desorption. Our data illustrate that BDE-15 and probably other PBDEs exhibit high sorption affinity to soils. Moreover, sorption is irreversible and thus PBDEs can potentially accumulate in the topsoil layer. We also suggest that although humin is probably a major sorbent for PBDEs in soils, other humic materials are also responsible for their sequestration. - Highlights: → BDE-15 exhibited pronounced desorption hysteresis. → BDE-15 sowed higher sorption affinity to humin as compared to the bulk soils. → Sequestration of PBDEs depends on soil organic matter constitutes other than humin. - Pronounced desorption hysteresis was observed for BDE-15 in natural soils.

  9. Influence of surface coverage on the chemical desorption process.

    Science.gov (United States)

    Minissale, M; Dulieu, F

    2014-07-01

    In cold astrophysical environments, some molecules are observed in the gas phase whereas they should have been depleted, frozen on dust grains. In order to solve this problem, astrochemists have proposed that a fraction of molecules synthesized on the surface of dust grains could desorb just after their formation. Recently the chemical desorption process has been demonstrated experimentally, but the key parameters at play have not yet been fully understood. In this article, we propose a new procedure to analyze the ratio of di-oxygen and ozone synthesized after O atoms adsorption on oxidized graphite. We demonstrate that the chemical desorption efficiency of the two reaction paths (O+O and O+O2) is different by one order of magnitude. We show the importance of the surface coverage: for the O+O reaction, the chemical desorption efficiency is close to 80% at zero coverage and tends to zero at one monolayer coverage. The coverage dependence of O+O chemical desorption is proved by varying the amount of pre-adsorbed N2 on the substrate from 0 to 1.5 ML. Finally, we discuss the relevance of the different physical parameters that could play a role in the chemical desorption process: binding energy, enthalpy of formation, and energy transfer from the new molecule to the surface or to other adsorbates.

  10. Sorption-desorption dynamics of radiocaesium in organic matter soils

    International Nuclear Information System (INIS)

    A systematic study has been carried out on the radiocaesium sorption properties of 25 soils (forest, peat) covering organic matter (OM) contents in the range of 10-97%. Predictions are made for radiocaesium partitioning between micaceous Frayed Edge Sites (FES) and regular exchange sites (RES) on the basis of specific radiocaesium interception potentials of the soil and overall exchange capacity. It is shown that for soils with a very high OM content (>80%), significant fractions are present in a readily reversible form in the OM phase. In soils of low-medium OM content (<40%), only a very minor fraction is present in the OM exchange complex. Experimental findings, based on a desorption screening with a variety of desorption agents are in agreement with these predictions. On the basis of a study of sorption kinetics, some additional tools are available for identifying problem soils. In cases of very high OM content, radiocaesium adsorption is completed within hours demonstrating the involvement of the OM sites. In soils for which interception occurs in the FES, sorption continues to proceed for periods of 2-3 weeks. In conclusion, some examples are presented on radiocaesium desorption using ion exchangers as radiocaesium sinks in promoting desorption. For a peaty soil, near quantitative desorption is accomplished. For forest soils with OM contents in a range of 10-40%, fixation levels of 30-50% are demonstrated

  11. Influence of surface coverage on the chemical desorption process

    Energy Technology Data Exchange (ETDEWEB)

    Minissale, M.; Dulieu, F., E-mail: francois.dulieu@obspm.fr [LERMA, Université de Cergy Pontoise et Observatoire de Paris, UMR 8112 du CNRS. 5, mail Gay Lussac, 95031 Cergy Pontoise (France)

    2014-07-07

    In cold astrophysical environments, some molecules are observed in the gas phase whereas they should have been depleted, frozen on dust grains. In order to solve this problem, astrochemists have proposed that a fraction of molecules synthesized on the surface of dust grains could desorb just after their formation. Recently the chemical desorption process has been demonstrated experimentally, but the key parameters at play have not yet been fully understood. In this article, we propose a new procedure to analyze the ratio of di-oxygen and ozone synthesized after O atoms adsorption on oxidized graphite. We demonstrate that the chemical desorption efficiency of the two reaction paths (O+O and O+O{sub 2}) is different by one order of magnitude. We show the importance of the surface coverage: for the O+O reaction, the chemical desorption efficiency is close to 80% at zero coverage and tends to zero at one monolayer coverage. The coverage dependence of O+O chemical desorption is proved by varying the amount of pre-adsorbed N{sub 2} on the substrate from 0 to 1.5 ML. Finally, we discuss the relevance of the different physical parameters that could play a role in the chemical desorption process: binding energy, enthalpy of formation, and energy transfer from the new molecule to the surface or to other adsorbates.

  12. Sorption-desorption behavior of polybrominated diphenyl ethers in soils

    Energy Technology Data Exchange (ETDEWEB)

    Olshansky, Yaniv; Polubesova, Tamara [Department of Soil and Water Sciences, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100 (Israel); Vetter, Walter [Institute of Food Chemistry (170b), University of Hohenheim, Garbenstr. 28, D-70599 Stuttgart (Germany); Chefetz, Benny, E-mail: chefetz@agri.huji.ac.il [Department of Soil and Water Sciences, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100 (Israel)

    2011-10-15

    Polybrominated diphenyl ethers (PBDEs) are flame retardants that are commonly found in commercial and household products. These compounds are considered persistent organic pollutants. In this study, we used 4,4'-dibromodiphenyl ether (BDE-15) as a model compound to elucidate the sorption and desorption behavior of PBDEs in soils. The organic carbon-normalized sorption coefficient (K{sub OC}) of BDE-15 was more than three times higher for humin than for bulk soils. However, pronounced desorption hysteresis was obtained mainly for bulk soils. For humin, increasing concentration of sorbed BDE-15 resulted in decreased desorption. Our data illustrate that BDE-15 and probably other PBDEs exhibit high sorption affinity to soils. Moreover, sorption is irreversible and thus PBDEs can potentially accumulate in the topsoil layer. We also suggest that although humin is probably a major sorbent for PBDEs in soils, other humic materials are also responsible for their sequestration. - Highlights: > BDE-15 exhibited pronounced desorption hysteresis. > BDE-15 sowed higher sorption affinity to humin as compared to the bulk soils. > Sequestration of PBDEs depends on soil organic matter constitutes other than humin. - Pronounced desorption hysteresis was observed for BDE-15 in natural soils.

  13. Cloning, bacterial expression and biological characterization of recombinant human granulocyte chemotactic protein-2 and differential expression of granulocyte chemotactic protein-2 and epithelial cell-derived neutrophil activating peptide-78 mRNAs.

    Science.gov (United States)

    Froyen, G; Proost, P; Ronsse, I; Mitera, T; Haelens, A; Wuyts, A; Opdenakker, G; Van Damme, J; Billiau, A

    1997-02-01

    Human osteosarcoma cells secrete a novel C-X-C chemokine called granulocyte chemotactic protein-2 (GCP-2), which was previously identified by amino acid sequencing of the purified natural protein. In order to understand the role of this new protein in inflammatory reactions, we cloned GCP-2 DNA sequences to generate recombinant protein and specific DNA probes and primers. By means of PCR on cloned cDNA of osteosarcoma cells induced by interleukin-1 beta and fibroblasts induced by lipopolysaccharide plus dsRNA, the complete coding domain of GCP-2 was isolated. This sequence was cloned into the bacterial expression vector pHEN1 and, after induction, GCP-2 was secreted into the periplasm of Escherichia coli. Recombinant GCP-2 (rGCP-2) was purified and characterized by SDS/PAGE as a monomeric 6.5-kDa protein and by amino-terminal sequencing. The chemoattractive potency of GCP-2 for neutrophilic granulocytes was about 10-times less than that of interleukin-8 and the minimal effective dose was 10 ng/ml. However, at optimal dose (100 ng/ml) the maximal chemotactic response was comparable with that of interleukin-8. Both characteristics correspond with those of natural GCP-2. In addition, intracellular calcium release in neutrophils by recombinant GCP-2 was achieved with as little as 10 ng/ml. Quantitation studies using reverse transcriptase and the polymerase chain reaction revealed higher GCP-2 mRNA production in normal fibroblasts than in tumor cells. When compared with epithelial-cell-derived neutrophil-activating peptide-78 (ENA-78) mRNA, the GCP-2 mRNA levels were higher in all cell lines tested. In addition, GCP-2 and ENA-78 expression seem to be differentially regulated in that phorbol ester and lipopolysaccharide have opposing effects on their mRNA induction in diploid fibroblasts and epithelial cells, respectively. Interleukin-1 was demonstrated to be a general inducer for both chemokines, while interferon-gamma down-regulates their mRNA expression. The

  14. Gene therapy for hemophilia B mediated by recombinant adeno-associated viral vector with hFIXR338A, a high catalytic activity mutation of human coagulation factor IX

    Institute of Scientific and Technical Information of China (English)

    LU; Huazhong; (

    2001-01-01

    [1]Chang, J., Jin, J., Lollar, P. et al., Changing residue 338 in human factor IX from arginine to alanine causes an increase in catalytic activity, J. Bio. Chem., 1998, 273 (20): 12089-12094.[2]Lai, L., Chen, L., Zhou, H. et al., Clinical phenotype and genetic stability of factor IX gene knock out mice, J. Fudan Uni., 1999, 38 (4): 435-438.[3]Wu, Z. J., Wu, X. B., Hou, Y. D., Generation of a recombinant herps simplex virus which can provide packaging function for recombinant adeno-associated virus, Chinese Sci. Bull., 1999, 44 (8): 715-719.[4]Snyder, R. O., Miao, C. H., Patijn, G. A. et al., Persistent and therapeutic concentrations of human factor IX in mice after hepatic gene transfer of recombinant AAV vectors, Nat. Genet., 1997, 16 (3): 270-276.[5]Lai, L. H., Chen, L., Wang, J. M. et al., Skeletal muscle-specific expression of human blood coagulation factor IX rescues factor IX deficiency mouse by AAV-mediated gene transfer, Science in China, Ser. C, 1999, 42 (6): 628-634.[6]Snyder, R. O., Miao, C., Meuse, L. et al., Correction of hemophilia B in canine and murine models using recombinant adeno-associated viral vectors, Nat. Med., 1999, 5 (1): 64-70.[7]Kung, S. H., Hagstrom, J. N., Cass, D. et al., Human factor IX corrects the bleeding diathesis of mice with hemophilia B, Blood, 1998, 91(3): 784-790.[8]Hirt, B., Selective extraction of polyoma DNA from infected mouse cell culture, J. Mol. Biol., 1967, 26: 365-369.[9]Sambrook, J., Fritsch, E., Maniatis, T., Molecular Cloning: A Laboratory Manual, New York: Cold Spring Harbor Laboratory Press, 1989, 6, 20-21.[10]Chao, H., Samulski, R. J., Bellinger, D. A. et al., Persistent expression of canine factor IX in hemophilia B canines, Gene Ther., 1999, 6: 1695-1704.[11]Kaufman, R. J., Advances toward gene therapy for hemophilia at the millennium, Hum. Gene Ther., 1999, 10 (13): 2091-2107.[12]Lu, D. R., Zhou, J. M., Zheng, B. et al., Stage I clinical trial of gene

  15. Recombinant expression systems for allergen vaccines.

    Science.gov (United States)

    Singh, Mohan B; Bhalla, Prem L

    2006-01-01

    Allergen immunotherapy of future is likely to be based on allergy vaccines that contain engineered allergens modified to abolish or substantially reduce their IgE-binding activity in order to remove the risk of unwanted anaphylactic responses. The development of efficient systems for the production of recombinant allergens in sufficient quantities is requirement for establishing use of engineered allergens as components of allergy vaccines. This review outlines relative advantages and disadvantages of various heterologous systems for production of recombinant allergens. Microbial systems are most convenient and cost effective platforms for the production of recombinant allergens. However, lack of post-translational processing implies that some allergens have to be expressed in eukaryotic systems for proper folding and post-translational modifications such as glycosylation. Yeast systems can yield high levels of recombinant allergens but often are associated with hyper- glycosylation problems. Mammalian cell culture systems offer suitable post -translational modifications but are nearly hundred fold more expensive than microbial systems. The use of plants as bio-factories for production of recombinant allergens is emerging as a very attractive option as plants-based production system offer several advantages over other expression systems such as post translational processing of proteins, low production costs, scale up ability and enhanced safety due to absence of animal or human pathogens.

  16. Processes for desorption from LiAlO sub 2 treated with H sub 2 as studied by temperature programmed desorption

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, A.K.

    1990-01-01

    The energetics and kinetics of the evolution of H{sub 2}O and H{sub 2} from LiAlO{sub 2} are being studied by the temperature programmed desorption technique. The concentrations of H{sub 2}, H{sub 2}O, N{sub 2}, and O{sub 2} in a helium stream during a temperature ramp are measured simultaneously with a mass spectrometer. Blank experiments with an empty sample tube showed that square wave spikes of H{sub 2} introduced into the helium gas stream were severely distorted by reaction with the tube walls. The tube could be stabilized, however, by sufficiently prolonged heat treatment with H{sub 2} so that H{sub 2} peaks would not be distorted up to approximately 923 K(650{degree}C). The amount of H{sub 2}adsorption/desorption is small compared to the amount of H{sub 2}O adsorption/desorption. After prolonged treatment with helium containing 990 ppm H{sub 2} at 400{degree}C, H{sub 2}O evolution into the He-H{sub 2} stream was observed during 473 to 1023 K (200 to 750{degree}C) ramps at rates of 2 or 5.6 K/min. The different peak shapes reflecting this process were deconvoluted to show that they are composites of only 2 or 3 reproducible processes. The activation energies and pre-exponential terms was evaluated. The different behavior originates in the differences among different surface sites for adsorption. The interpretation of higher temperature peaks (above 873 K (650{degree}C)) must still consider the possibility of contributions from interactions with steel walls. It was found that H{sub 2} enhances evolution of N{sub 2} from the steel. 1 tab., 6 figs., 11 refs.

  17. AECL passive autocatalytic recombiners

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, L.B.; Marcinkowska, K. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2012-03-15

    Atomic Energy of Canada Limited's (AECL) Passive Autocatalytic Recombiner (PAR) is a passive device used for hydrogen mitigation under post-accident conditions in nuclear reactor containment. The PAR employs a proprietary AECL catalyst which promotes the exothermal reaction between hydrogen and oxygen to form water vapour. The heat of reaction combined with the PAR geometry establishes a convective flow through the recombiner, where ambient hydrogen-rich gas enters the PAR inlet and hot, humid, hydrogen-depleted gas exits the outlet. AECL's PAR has been extensively qualified for CANDU and light water reactors (LWRs), and has been supplied to France, Finland, Ukraine, South Korea and is currently being deployed in Canadian nuclear power plants. (author)

  18. AECL passive autocatalytic recombiners

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, L.B.; Marcinkowska, K. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2011-07-01

    Atomic Energy of Canada Limited's (AECL) Passive Autocatalytic Recombiner (PAR) is a passive device used for hydrogen mitigation under post-accident conditions in nuclear reactor containment. The PAR employs a proprietary AECL catalyst which promotes the exothermal reaction between hydrogen and oxygen to form water vapour. The heat of reaction combined with the PAR geometry establishes a convective flow through the recombiner, where ambient hydrogen-rich gas enters the PAR inlet and hot, humid, hydrogen-depleted gas exits the outlet. AECL's PAR has been extensively qualified for CANDU and light water reactors (LWRs), and has been supplied to France, Finland, Ukraine, South Korea and is currently being deployed in Canadian nuclear power plants. (author)

  19. Thermal desorption analysis of beryllium tile pieces from JET

    International Nuclear Information System (INIS)

    Pieces of beryllium tile exposed to a D-D plasma in JET have been studied by thermal desorption spectroscopy. These tiles have a thick layer of redeposited Be-C-O with considerable hydrogen and deuterium present. The samples were heated at a constant rate of 2 C/min. from 100 C to 900 C. Desorption peaks occurred in the range of 140-480 C. There was no significant desorption at temperatures above 600 C. The amount of deuterium detected varied from a low of 8 x 1021/m2 to a high of 2.1 x 1023/m2. In one case, the amount of deuterium in a tile piece was seven times greater than the amount in a neighboring tile piece. Some of the tile pieces in the plasma-exposed region showed surface melting. Despite this, the deuterium yield from one of these pices is >1023/m2. (orig.)

  20. Desorption Mass Spectrometry for Nonvolatile Compounds Using an Ultrasonic Cutter

    Science.gov (United States)

    Habib, Ahsan; Ninomiya, Satoshi; Chen, Lee Chuin; Usmanov, Dilshadbek T.; Hiraoka, Kenzo

    2014-07-01

    In this work, desorption of nonvolatile analytes induced by friction was studied. The nonvolatile compounds deposited on the perfluoroalkoxy substrate were gently touched by an ultrasonic cutter oscillating with a frequency of 40 kHz. The desorbed molecules were ionized by a dielectric barrier discharge (DBD) ion source. Efficient desorption of samples such as drugs, pharmaceuticals, amino acids, and explosives was observed. The limits of detection for these compounds were about 1 ng. Many compounds were detected in their protonated forms without undergoing significant fragmentation. When the DBD was off, no ions for the neutral samples could be detected, meaning that only desorption along with little ionization took place by the present technique.

  1. Femtosecond laser pulse induced desorption: A molecular dynamics simulation

    Science.gov (United States)

    Lončarić, Ivor; Alducin, Maite; Saalfrank, Peter; Juaristi, J. Iñaki

    2016-09-01

    In recent simulations of femtosecond laser induced desorption of molecular oxygen from the Ag(110) surface, it has been shown that depending on the properties (depth and electronic environment) of the well in which O2 is adsorbed, the desorption can be either induced dominantly by hot electrons or via excitations of phonons. In this work we explore whether the ratios between the desorption yields from different adsorption wells can be tuned by changing initial surface temperature and laser pulse properties. We show that the initial surface temperature is an important parameter, and that by using low initial surface temperatures the electronically mediated process can be favored. In contrast, laser properties seem to have only a modest influence on the results.

  2. A study of the process of desorption of hexavalent chromium

    Directory of Open Access Journals (Sweden)

    W.B. Amorim

    2003-09-01

    Full Text Available In this work the process of desorption of hexavalent chromium, a toxic metal ion, from the marine algae Sargassum sp, following biosorption experiments 2³ factorial design was studied. A technique was applied to three eluents: HCl, H2SO4 and EDTA. Three factors of importance were evaluated: concentration of eluent, the ratio between mass of biosorbent and volume of eluent (S/L and process time. A statistical analysis of the experimental results showed that the three variables evaluated are significant for all three eluents. The models for chromium desorption were validated, as the results agreed well with the observed values. Through use of the response surface methodology, a factorial design based optimization technique; it was possible to identify the most suitable eluent and the interval of values for the process variables that resulted in the most significant desorption of chromium, which is relevant information for work aiming at process optimization.

  3. Desorption Dynamics, Internal Energies and Imaging of Organic Molecules from Surfaces with Laser Desorption and Vacuum Ultraviolet (VUV) Photoionization

    Energy Technology Data Exchange (ETDEWEB)

    Kostko, Oleg; Takahashi, Lynelle K.; Ahmed, Musahid

    2011-04-05

    There is enormous interest in visualizing the chemical composition of organic material that comprises our world. A convenient method to obtain molecular information with high spatial resolution is imaging mass spectrometry. However, the internal energy deposited within molecules upon transfer to the gas phase from a surface can lead to increased fragmentation and to complications in analysis of mass spectra. Here it is shown that in laser desorption with postionization by tunable vacuum ultraviolet (VUV) radiation, the internal energy gained during laser desorption leads to minimal fragmentation of DNA bases. The internal temperature of laser-desorbed triacontane molecules approaches 670 K, whereas the internal temperature of thymine is 800 K. A synchrotron-based VUV postionization technique for determining translational temperatures reveals that biomolecules have translational temperatures in the range of 216-346 K. The observed low translational temperatures, as well as their decrease with increased desorption laser power is explained by collisional cooling. An example of imaging mass spectrometry on an organic polymer, using laser desorption VUV postionization shows 5 mu m feature details while using a 30 mu m laser spot size and 7 ns duration. Applications of laser desorption postionization to the analysis of cellulose, lignin and humic acids are briefly discussed.

  4. RECOMBINANT INFLUENZA VACCINES

    OpenAIRE

    Sedova, E.; Shcherbinin, D.; Migunov, A.; Smirnov, Iu; Logunov, D.; Shmarov, M.; Tsybalova, L.; Naroditskiĭ, B.; O. Kiselev; Gintsburg, A.

    2012-01-01

    This review covers the problems encountered in the construction and production of new recombinant influenza vaccines. New approaches to the development of influenza vaccines are investigated; they include reverse genetics methods, production of virus-like particles, and DNA- and viral vector-based vaccines. Such approaches as the delivery of foreign genes by DNA- and viral vector-based vaccines can preserve the native structure of antigens. Adenoviral vectors are a promising gene-delivery pla...

  5. Recombinant human bone morphogenetic protein induces bone formation

    International Nuclear Information System (INIS)

    The authors have purified and characterized active recombinant human bone morphogenetic protein (BMP) 2A. Implantation of the recombinant protein in rats showed that a single BMP can induce bone formation in vivo. A dose-response and time-course study using the rat ectopic bone formation assay revealed that implantation of 0.5-115 μg of partially purified recombinant human BMP-2A resulted in cartilage by day 7 and bone formation by day 14. The time at which bone formation occurred was dependent on the amount of BMP-2A implanted; at high doses bone formation could be observed at 5 days. The cartilage- and bone-inductive activity of the recombinant BMP-2A is histologically indistinguishable from that of bone extracts. Thus, recombinant BMP-2A has therapeutic potential to promote de novo bone formation in humans

  6. The Effect of Recombinant Ghrelin Plasmid on Pepsin and Proton Pump Activity in Rats%重组生长素对大鼠胃蛋白酶和质子泵活性的影响

    Institute of Scientific and Technical Information of China (English)

    杜改梅; 晏文梅; 胡志华; 蒋加进; 罗碧平

    2012-01-01

    10 weaned rats are randomly divided into treatment and control groups to explore the impact of recombinant ghrelin plasmid on pepsin and proton pump activity. After 5 days, rats in the treatment group are injected with recombinant human growth hormone in the leg muscle. The research is lasted for 29 days. Rats are killed after the test is complete. The stomach is separated and weighed. The gastric mucosa is taken for pepsin and proton activity. The results show that the pepsin and proton pump activity are significantly increased in the treatment group. Therefore, ghrelin can promote gastric exocrine function.%研究生长素对大鼠胃蛋白酶和质子泵活性的影响。取10只刚断乳大鼠,随机分为试验组和对照组。预饲5d后,给试验组大鼠腿部肌肉注射重组生长紊,试验29d。试验结束后处死大鼠,分离胃,称重,取胃粘膜组织测定质子泵活性和胃蛋白酶活性。结果发现试验组大鼠质子泵和胃蛋白酶活性显著高于对照组,提示Ghrelin可以促进对胃外分泌功能具有重要的调节作用。

  7. Gene therapy for hemophilia B mediated by recombinant adeno-associated viral vector with hFIXR338A, a high catalytic activity mutation of human coagulation factor IX

    Institute of Scientific and Technical Information of China (English)

    陆华中; 陈立; 王红卫; 伍志坚; 吴小兵; 王学峰; 王鸿利; 卢大儒; 邱信芳; 薛京伦

    2001-01-01

    A mutant human factor IX with arginine at 338 residual changed to alanine (hFIXR338A) by site-directed mutagenesis was introduced into AAV vectors, and a recombinant adeno-associ- ated viral vector containing hFIXR338A, prepared by rHSV/AAV hybrid helper virus system, was directly introduced to the hind leg muscle of factor IX knock out mice. The expression and the biological activity of human factor IX mutant, hFIXR338A, and the immune response against it in the treated mice were assayed and detected. The results showed that (i) the high-level expression of human factor IX mutant protein, hFIXR338A, has been detected in rAAV-hFIXR338A treated hemophilia B mice and lasted more than 15 weeks; (ii) the clotting activity of hFIXR338A in plasma is 34.2%± 5.23%, which is remarkably higher than that of (14.27% ± 3.4%) of wild type hFIX treated mice in the activated partial thromboplastin assay; (iii) immune response against factor IX R338A was absent, with no factor IX mutant protein (hFIXR338A) inhibitors development in the treated mice; and (iv) no local or systemic side-effects and toxicity associated with the gene transfer were found. It demonstrated the potential use of treating hemophilia B by recombinant adeno-associated viral vectors with mutant hFIXR338A gene, an alternative strategy for hemophilia B gene therapy to wild-type human factor IX.

  8. Failure of low-dose recombinant human IL-2 to support the survival of virus-specific CTL clones infused into severe combined immunodeficient foals: lack of correlation between in vitro activity and in vivo efficacy.

    Science.gov (United States)

    Mealey, Robert H; Littke, Matt H; Leib, Steven R; Davis, William C; McGuire, Travis C

    2008-01-15

    Although CTL are important for control of lentiviruses, including equine infectious anemia virus (EIAV), it is not known if CTL can limit lentiviral replication in the absence of CD4 help and neutralizing antibody. Adoptive transfer of EIAV-specific CTL clones into severe combined immunodeficient (SCID) foals could resolve this issue, but it is not known whether exogenous IL-2 administration is sufficient to support the engraftment and proliferation of CTL clones infused into immunodeficient horses. To address this question we adoptively transferred EIAV Rev-specific CTL clones into four EIAV-challenged SCID foals, concurrent with low-dose aldesleukin (180,000U/m2), a modified recombinant human IL-2 (rhuIL-2) product. The dose was calculated based on the specific activity on equine PBMC in vitro, and resulted in plasma concentrations considered sufficient to saturate high affinity IL-2 receptors in humans. Despite specific activity on equine PBMC that was equivalent to recombinant equine IL-2 and another form of rhuIL-2, aldesleukin did not support the engraftment and expansion of infused CTL clones, and control of viral load and clinical disease did not occur. It was concluded that survival of Rev-specific CTL clones infused into EIAV-challenged SCID foals was not enhanced by aldesleukin at the doses used in this study, and that in vitro specific activity did not correlate with in vivo efficacy. Successful adoptive immunotherapy with CTL clones in immunodeficient horses will likely require higher doses of rhuIL-2, co-infusion of CD4+ T lymphocytes, or administration of equine IL-2. PMID:17727961

  9. Heavy-Ion-Induced Electronic Desorption of Gas from Metals

    CERN Document Server

    Molvik, A W; Mahner, E; Kireeff Covo, M; Bellachioma, M C; Bender, M; Bieniosek, F M; Hedlund, E; Krämer, A; Kwan, J; Malyshev, O B; Prost, L; Seidl, P A; Westenskow, G; Westerberg, L

    2007-01-01

    During heavy-ion operation in several particle accelerators worldwide, dynamic pressure rises of orders of magnitude were triggered by lost beam ions that bombarded the vacuum chamber walls. This ion-induced molecular desorption, observed at CERN, GSI, and BNL, can seriously limit the ion beam lifetime and intensity of the accelerator. From dedicated test stand experiments we have discovered that heavy-ion-induced gas desorption scales with the electronic energy loss (dEe/dx) of the ions slowing down in matter; but it varies only little with the ion impact angle, unlike electronic sputtering.

  10. Sorption and desorption of arsenate and arsenite on calcite

    DEFF Research Database (Denmark)

    Sø, Helle Ugilt; Postma, Diederik Jan; Jakobsen, Rasmus;

    2008-01-01

    The adsorption and desorption of arsenate (As(V)) and arsenite (As(111)) oil calcite was investigated in a series of batch experiments in calcite-equilibrated solutions. The solutions covered a broad range of pH, alkalinity, calcium concentration and ionic strength. The initial arsenic concentrat......The adsorption and desorption of arsenate (As(V)) and arsenite (As(111)) oil calcite was investigated in a series of batch experiments in calcite-equilibrated solutions. The solutions covered a broad range of pH, alkalinity, calcium concentration and ionic strength. The initial arsenic...

  11. Heavy-ion induced electronic desorption of gas from metals

    Energy Technology Data Exchange (ETDEWEB)

    Molvik, A W; Kollmus, H; Mahner, E; Covo, M K; Bellachioma, M C; Bender, M; Bieniosek, F M; Hedlund, E; Kramer, A; Kwan, J; Malyshev, O B; Prost, L; Seidl, P A; Westenskow, G; Westerberg, L

    2006-12-19

    During heavy ion operation in several particle accelerators world-wide, dynamic pressure rises of orders of magnitude were triggered by lost beam ions that bombarded the vacuum chamber walls. This ion-induced molecular desorption, observed at CERN, GSI, and BNL, can seriously limit the ion beam lifetime and intensity of the accelerator. From dedicated test stand experiments we have discovered that heavy-ion induced gas desorption scales with the electronic energy loss (dE{sub e}/d/dx) of the ions slowing down in matter; but it varies only little with the ion impact angle, unlike electronic sputtering.

  12. Kinetics of desorption of iodine from borehole waters

    International Nuclear Information System (INIS)

    Kinetics of mass transfer during iodine desorption by air from water-salt systems and borehole waters of different composition has been studied. With an aid of laboratory installation with film column and sprinkled walls the region of the process procedure in a wide range of phases, concentrations (aqueous iodine solution, sodium chloride solution) and temperatures is determined. Calculation and experimental values of kinetic parameters are obtained. It follows from the data analysis that the process of iodine desorption is complicated by reversible reaction of complexing, its rate being higher than the rate of mass transfer

  13. A recombinant Sp185/333 protein from the purple sea urchin has multitasking binding activities towards certain microbes and PAMPs.

    Science.gov (United States)

    Lun, Cheng Man; Schrankel, Catherine S; Chou, Hung-Yen; Sacchi, Sandro; Smith, L Courtney

    2016-08-01

    The purple sea urchin, Strongylocentrotus purpuratus, possesses a sophisticated innate immune system that responds to microbes effectively by swift expression of the highly diverse Sp185/333 gene family. The Sp185/333 proteins are predicted to have anti-pathogen functions based on inducible gene expression and their significant sequence diversity. Sp185/333 proteins are all predicted to be intrinsically disordered and do not exhibit sequence similarities to other known proteins. To test the anti-pathogen hypothesis, a recombinant Sp185/333 protein, rSp0032, was evaluated and found to exhibit specific binding to marine Vibrio diazotrophicus and to Saccharomyces cerevisiae, but not to two Bacillus species. rSp0032 also binds to LPS, β-1,3-glucan and flagellin but not to peptidoglycan. rSp0032 binding to LPS can be competed by LPS, β-1,3-glucan and flagellin but not by peptidoglycan. We speculate that the predicted intrinsically disordered structure of rSp0032 may adapt to different conformations in binding to a limited number of PAMPs and pathogens. Given that rSp0032 binds to a range of targets, and that up to 260 different Sp185/333 proteins can be expressed per individual sea urchin, this family of immune response proteins may facilitate effective host protection against a broad array of potential pathogens encountered in the marine environment.

  14. Production of soluble recombinant proteins with Kell, Duffy and Lutheran blood group antigen activity, and their use in screening human sera for Kell, Duffy and Lutheran antibodies.

    Science.gov (United States)

    Ridgwell, K; Dixey, J; Scott, M L

    2007-10-01

    The aim of this study was to show that soluble recombinant (sr) proteins can mimic blood group antigens and be used to screen human sera for blood-group-specific antibodies. The blood of all pregnant women and pretransfusion patients should be screened for blood-group-specific antibodies to identify and monitor pregnancies at risk of haemolytic disease of the foetus and newborn (HDFN), and to prevent haemolytic transfusion reactions. Current antibody screening and identification methods use human red blood cell panels, which can complicate antibody identification if more than one antibody specificity is present. COS-7 cells were transfected to produce sr forms of the extracellular domains of the red blood cell membrane proteins that express Kell, Duffy or Lutheran blood group antigens. These sr proteins were used to screen for and identify anti-Kell, anti-Duffy or anti-Lutheran blood-group-specific allo-antibodies in human sera by haemagglutination inhibition and in solid-phase enzyme-linked immunosorbent assays (ELISAs). There is a positive correlation (correlation coefficient 0.605, P value 0.002) between antibody titre by standard indirect antiglobulin test (IAT) and signal intensity in the ELISA test. This work shows that sr proteins can mimic blood group antigens and react with human allogeneic antibodies, and that such proteins could be used to develop solid-phase, high-throughput blood group antibody screening and identification platforms. PMID:17725551

  15. Correcting for electrocatalyst desorption and inactivation in chronoamperometry experiments.

    Science.gov (United States)

    Fourmond, Vincent; Lautier, Thomas; Baffert, Carole; Leroux, Fanny; Liebgott, Pierre-Pol; Dementin, Sébastien; Rousset, Marc; Arnoux, Pascal; Pignol, David; Meynial-Salles, Isabelle; Soucaille, Phillippe; Bertrand, Patrick; Léger, Christophe

    2009-04-15

    Chronoamperometric experiments with adsorbed electrocatalysts are commonly performed either for analytical purposes or for studying the catalytic mechanism of a redox enzyme. In the context of amperometric sensors, the current may be recorded as a function of time while the analyte concentration is being increased to determine a linearity range. In mechanistic studies of redox enzymes, chronoamperometry proved powerful for untangling the effects of electrode potential and time, which are convoluted in cyclic voltammetric measurements, and for studying the energetics and kinetics of inhibition. In all such experiments, the fact that the catalyst's coverage and/or activity decreases over time distorts the data. This may hide meaningful features, introduce systematic errors, and limit the accuracy of the measurements. We propose a general and surprisingly simple method for correcting for electrocatalyst desorption and inactivation, which greatly increases the precision of chronoamperometric experiments. Rather than subtracting a baseline, this consists in dividing the current, either by a synthetic signal that is proportional to the instant electroactive coverage or by the signal recorded in a control experiment. In the latter, the change in current may result from film loss only or from film loss plus catalyst inactivation. We describe the different strategies for obtaining the control signal by analyzing various data recorded with adsorbed redox enzymes: nitrate reductase, NiFe hydrogenase, and FeFe hydrogenase. In each case we discuss the trustfulness and the benefit of the correction. This method also applies to experiments where electron transfer is mediated, rather than direct, providing the current is proportional to the time-dependent concentration of catalyst. PMID:19298055

  16. Carbon dioxide sorption/ desorption characteristics of coals in Taiwan

    Science.gov (United States)

    Chien-Hung, Hsiao; Loung-Yie, Tsai

    2013-04-01

    Geological sequestration of CO2 into depleted oil reservoir, saline aquifer or unmineable coal seam is now being actively investigated for the purpose of reducing greenhouse gas in the atmosphere. Understanding the physical, chemical, and thermodynamic phenomena occurred with CO2 injection is very important in marking a reliable prediction of sequestration. This study examined the feasibility of carbon dioxide sequestration into unmineable coal seams in Taiwan. A total of 20 Miocene-aged coal samples from Western Foothill Belt, NW Taiwan, were collected. The stratigraphy include Mushan, Shihti, and Nanchuang Formation from bottom up. Proximate and petrographic analyses include maceral composition, Vitrinite reflectance were also measured. Carbon dioxide adsorption isotherms were analyzed at 35 degrees Celsius and up to 800 psi, by using a gravimetric ad/desorption apparatus. Isotherms were then fitted with a modified Langmuir Isotherm model by using Langmuir Pressure and Langmuir Volume so the model can be applied to supercritical conditions. According to the result of adsorption experiment, the pressure and temperature were quite significant. The gas storage capacity of CO2 was about 400 600 scf/ton at pressure up to 800 psi. Comparing the results of adsorption capacity with Proximate analysis and vitrinite reflectance, the Langmuir Volume shows a strong positive correlation with fixed carbon and vitrinite content. Furthermore, Adsorption capacity is closely related to micropores which were also rank and maceral dependent. It is noticed that the observed coal pore structures were affected by rank, and then exhibit have different diffusion rate of CO2.Finally, images under SEM were evaluated to understand the pathways of gas sorption.

  17. Genetic and biochemical evidence that recombinant Enterococcus spp. strains expressing gelatinase (GelE) produce bovine milk-derived hydrolysates with high angiotensin converting enzyme-inhibitory activity (ACE-IA).

    Science.gov (United States)

    Gútiez, Loreto; Borrero, Juan; Jiménez, Juan J; Gómez-Sala, Beatriz; Recio, Isidra; Cintas, Luis M; Herranz, Carmen; Hernández, Pablo E

    2014-06-18

    In this work, genes encoding gelatinase (gelE) and serine proteinase (sprE), two extracellular proteases produced by Enterococcus faecalis DBH18, were cloned in the protein expression vector pMG36c, containing the constitutive P32 promoter, generating the recombinant plasmids pCG, pCSP, and pCGSP encoding gelE, sprE, and gelE-sprE, respectively. Transformation of noncaseinolytic E. faecalis P36, E. faecalis JH2-2, E. faecium AR24, and E. hirae AR14 strains with these plasmids permitted detection of caseinolytic activity only in the strains transformed with pCG or pCGSP. Complementation of a deletion (knockout) mutant of E. faecalis V583 for production of gelatinase (GelE) with pCG unequivocally supported that gelE is responsible for the caseinolytic activity of the transformed strain grown in bovine skim milk (BSM). RP-HPLC-MS/MS analysis of hydrolysates of transformed Enterococcus spp. strains grown in BSM permitted the identification of 38 major peptide fragments including peptides with previously reported angiotensin converting enzyme-inhibitory activity (ACE-IA), antihypertensive activity, and antioxidant activity.

  18. Recombinant CBM-fusion technology : applications overview

    OpenAIRE

    Oliveira, Carla Cristina Marques de; Carvalho, Vera; Domingues, Lucília; Gama, F. M.

    2015-01-01

    Carbohydrate-binding modules (CBMs) are small components of several enzymes, which present an independent fold and function, and specific carbohydrate-binding activity. Their major function is to bind the enzyme to the substrate enhancing its catalytic activity, especially in the case of insoluble substrates. The immense diversity of CBMs, together with their unique properties, has long raised their attention for many biotechnological applications. Recombinant DNA technology has been used for...

  19. Defect annealing and thermal desorption of deuterium in low dose HFIR neutron-irradiated tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Masashi Shimada; M. Hara; T. Otsuka; Y. Oya; Y. Hatano

    2014-05-01

    Accurately estimating tritium retention in plasma facing components (PFCs) and minimizing its uncertainty are key safety issues for licensing future fusion power reactors. D-T fusion reactions produce 14.1 MeV neutrons that activate PFCs and create radiation defects throughout the bulk of the material of these components. Recent studies show that tritium migrates and is trapped in bulk (>> 10 µm) tungsten beyond the detection range of nuclear reaction analysis technique [1-2], and thermal desorption spectroscopy (TDS) technique becomes the only established diagnostic that can reveal hydrogen isotope behavior in in bulk (>> 10 µm) tungsten. Radiation damage and its recovery mechanisms in neutron-irradiated tungsten are still poorly understood, and neutron-irradiation data of tungsten is very limited. In this paper, systematic investigations with repeated plasma exposures and thermal desorption are performed to study defect annealing and thermal desorption of deuterium in low dose neutron-irradiated tungsten. Three tungsten samples (99.99 at. % purity from A.L.M.T. Co., Japan) irradiated at High Flux Isotope Reactor at Oak Ridge National Laboratory were exposed to high flux (ion flux of (0.5-1.0)x1022 m-2s-1 and ion fluence of 1x1026 m-2) deuterium plasma at three different temperatures (100, 200, and 500 °C) in Tritium Plasma Experiment at Idaho National Laboratory. Subsequently, thermal desorption spectroscopy (TDS) was performed with a ramp rate of 10 °C/min up to 900 °C, and the samples were annealed at 900 °C for 0.5 hour. These procedures were repeated three (for 100 and 200 °C samples) and four (for 500 °C sample) times to uncover damage recovery mechanisms and its effects on deuterium behavior. The results show that deuterium retention decreases approximately 90, 75, and 66 % for 100, 200, and 500 °C, respectively after each annealing. When subjected to the same TDS recipe, the desorption temperature shifts from 800 °C to 600 °C after 1st annealing

  20. Though active on RINm5F insulinoma cells and cultured pancreatic islets, recombinant IL-22 fails to modulate cytotoxicity and disease in a protocol of streptozotocin-induced experimental diabetes.

    Directory of Open Access Journals (Sweden)

    Anika eBerner

    2016-01-01

    Full Text Available Interleukin (IL-22 is a cytokine displaying tissue protective and pro-regenerative functions in various preclinical disease models. Anti-bacterial, pro-proliferative, and anti-apoptotic properties mediated by activation of the transcription factor signal transducer and activator of transcription (STAT-3 are key to biological functions of this IL-10 family member. Herein, we introduce RINm5F insulinoma cells as rat ß-cell line that, under the influence of IL-22, displays activation of STAT3 with induction of its downstream gene targets Socs3, Bcl3, and Reg3ß. In addition, IL-22 also activates STAT1 in this cell type. To refine those observations, IL-22 biological activity was evaluated using ex vivo cultivated murine pancreatic islets. In accord with data on RINm5F cells, islet exposure to IL-22 activated STAT3 and upregulation of STAT3-inducible Socs3, Bcl3, and STEAP4 was evident under those conditions. As these observations supported the hypothesis that IL-22 may exert protective functions in toxic ß-cell injury, application of IL-22 was investigated in murine multiple-low-dose streptozotocin (STZ-induced diabetes. For that purpose, recombinant IL-22 was administered thrice either immediately before and at disease onset (at d4, d6, d8 or closely thereafter (at d8, d10, d12. These two IL-22-treatment periods coincide with two early peaks of ß-cell injury detectable in this model. Notably, none of the two IL-22-treatment strategies affected diabetes incidence or blood glucose levels in STZ-treated mice. Moreover, pathological changes in islet morphology analyzed 28 days after disease induction were not ameliorated by IL-22 administration. Taken together, despite being active on rat RINm5F insulinoma cells and murine pancreatic islets, recombinant IL-22 fails to protect pancreatic ß-cells in the tested protocols from toxic effects of STZ and thus is unable to ameliorate disease in the widely used model of STZ-induced diabetes.

  1. [Modification of recombinant human augmenter of liver regeneration with urea studied by maldi-tof mass spectrometry].

    Science.gov (United States)

    Pan, Yun; He, Guo-Qing; Li, Ru-Bing; Yi, Xue-Rui; Kong, Xiang-Ping

    2003-04-01

    To investigate the modification of recombinant human augmenter of liver regeneration (rhALR) by the urea in purification processes and the biological activity of rhALR and modified rhALR, the molecular weight of proteins and tryptic peptides were determined by matrix-assisted laser desorption time of flight mass spectrometry (MALDI-TOF-MS), and the biological activity of rhALR and modified rhALR was also observed by in vivo experiments. A 30 kD homodimer of rhALR was purified under denaturing conditions. The molecular weight of rhALR is 30 780 if urea was used to denature the inclusion bodies; when the denaturant was guanidine hydrochloride, the molecular weight of rhALR was 30 087. The results of MALDI-TOF-MS of digested rhALR that have been modified by urea showed that peptides that contained lysyl were 43 larger than the theoretical value. Proteins purified by different processes were all able to promote the survival rate of CCl(4)-intoxicated mice. It could be concluded that cyanate, the cleavage product of urea, could react with the epsilon-amino group of lysyl in rhALR, and the modified rhALR had the same biological activity as natural rhALR.

  2. Thermal desorption of deuterium from Be, and Be with helium bubbles

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, A.V.; Van Veen, A.; Busker, G.J. [Delft Univ. of Technology (Netherlands). Interfaculty Reactor Inst.

    1998-01-01

    Deuterium desorption measurements carried out on a single-crystalline beryllium sample are presented. Deuterium ions were implanted at room temperature at the energy of 0.7 and 1.2 keV up to doses ranging from 10{sup 19} to 3.6 x 10{sup 21} m{sup -2}. In order to eliminate the influence of the beryllium-oxide surface layer, before the implantation the surface of the sample was cleaned by argon sputtering. After the implantation the sample was annealed up to 1200 K at a constant rate of 10 K/s. Deuterium released from the sample was monitored by a calibrated quadrupole mass-spectrometer. The desorption spectra revealed two different contributions. One is a well defined and very narrow peak centered around 450 K. This peak is observed only at high implantation doses > 7.8 x 10{sup 20} m{sup -2}, which is close to the deuterium saturation limit of 0.3 D/Be and is related to deuterium release from blisters or interconnected bubbles. The activation energy of 1.1 eV and the threshold implantation dose are consistent with the values reported in literature. The second contribution in the release spectra is found in the temperature range from 600 to 900 K and is present throughout the whole range of the implantation doses. The activation energies corresponding to this release lie in the range between 1.8 and 2.5 eV and are ascribed to the release from deuterium-vacancy type of defects. In a number of experiments the deuterium implantation was preceded by helium implantation followed by partial annealing to create helium bubbles. The resulting deuterium desorption spectra indicate that deuterium detrapping from helium bubbles is characterized by an activation energy of 2.7 eV. (author)

  3. Improving peroxidase-like activity of hemoglobin by recombining hemoglobin using chemically modified heme%修饰血红素提高血红蛋白类过氧化物酶活性

    Institute of Scientific and Technical Information of China (English)

    凌辉生; 李阳; 封琳; 李任强

    2011-01-01

    The phenol or 4-biphenylol was used to modify the heme. The modified hemin group was recombined with apo-hemoglobin to prepare novel artificial hemoglobin. Absorption spectral sean demonstrated that the artificial recombined hemoglobins with modified heme were obtained. Experimental resultsshowed that the peroxidase-like activity of modified hemoglobins was enhanced compared with that of native hemoglobin. And the enzymatic activity of modified hemoglobin with 4-biphenylol modified heme was as about 1.6 folds than that of the native hemoglobin.%利用苯酚或对羟基联苯时血红蛋白的血红素辅基进行化学修饰,将修饰后的血红素与脱辅基血红蛋白进行重组得到新的血红蛋白.以光吸收扫描分析修饰血红素和重组血红蛋白,证明新的重组血红蛋白构建成功.酶活力测定表明,修饰血红素得到的重组血红蛋白的类过氧化物酶活性都比天然血红蛋白的酶活力高,用对羟基联笨修饰血红素得到的重组血红蛋白的酶活提高明显,约是天然血红蛋白的1.6倍.

  4. Desorption-diffusion model and lost gas quantity estimation of coalbed methane from coal core under drilling fluid medium

    Institute of Scientific and Technical Information of China (English)

    Geoff; WANG

    2010-01-01

    The differences of coalbed methane(CBM) desorption-diffusion from coal drilling-core under various drilling fluid medium are not considered in the present calculating methods of lost CBM quantity,which leads possibly to the inaccuracy of CBM quantity in coal seam.Here we took the desorption of CBM from coal core under drilling fluid medium as a pressure-swing process,and based on the Langmuir equation and Fick-first law,established the desorption-diffusion model and numerical modeling method of lost gas(including free CBM) calculation in coal core under various drilling fluid mediums through physical simulation test and by considering comprehensively primary factors.The results showed that the physical simulated t-Qt curves can be rightly fitted by the numerical modeling data,which indicated the ultimate desorption quantity from the numerical modeling was adjacent to that from the physical simulation as a whole.It was found that the lost CBM quantity from the modeling method was generally higher than that from the direct method when lost time was relatively long.Thus,we sug-gest that it is necessary to emend the active China national standard through further investigation,since the lost CBM quantity from coal drilling-core was generally underestimated using the method in the current standard.

  5. Nitrogen Molecule Adsorption on Cationic Tantalum Clusters and Rhodium Clusters and Desorption from Their Nitride Clusters Studied by Thermal Desorption Spectrometry.

    Science.gov (United States)

    Mafuné, Fumitaka; Tawaraya, Yuki; Kudoh, Satoshi

    2016-06-23

    Adsorption and desorption of N2 molecules onto cationic Ta and Rh clusters in the gas phase were investigated in the temperature range of 300-1000 K by using thermal desorption spectrometry in combination with density functional theory (DFT) calculations. For Ta6(+), the first N2 molecule was found to adsorb dissociatively, and it remained adsorbed when Ta6(+)N2 was heated to 1000 K. In contrast, the second and the subsequent N2 molecules adsorbed weakly as a molecular form and were released into the gas phase when heated to 600 K. The difference can be explained in terms of the activation barrier between the molecular and dissociative forms. On the other hand, when Ta clusters were generated in the presence of N2 gas by the laser ablation of a Ta rod, isomeric clusters, TanNm(+), having heat resistivity were formed. For Rh6(+), N2 adsorbed molecularly at 300 K and desorbed totally at 450 K. These results were consistent with the DFT calculations, indicating that the dissociative adsorption of N2 is endothermic. PMID:27276438

  6. Fundamental Studies of Recombinant Hydrogenases

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Michael W

    2014-01-25

    This research addressed the long term goals of understanding the assembly and organization of hydrogenase enzymes, of reducing them in size and complexity, of determining structure/function relationships, including energy conservation via charge separation across membranes, and in screening for novel H2 catalysts. A key overall goal of the proposed research was to define and characterize minimal hydrogenases that are produced in high yields and are oxygen-resistant. Remarkably, in spite of decades of research carried out on hydrogenases, it is not possible to readily manipulate or design the enzyme using molecular biology approaches since a recombinant form produced in a suitable host is not available. Such resources are essential if we are to understand what constitutes a “minimal” hydrogenase and design such catalysts with certain properties, such as resistance to oxygen, extreme stability and specificity for a given electron donor. The model system for our studies is Pyrococcus furiosus, a hyperthermophile that grows optimally at 100°C, which contains three different nickel-iron [NiFe-] containing hydrogenases. Hydrogenases I and II are cytoplasmic while the other, MBH, is an integral membrane protein that functions to both evolve H2 and pump protons. Three important breakthroughs were made during the funding period with P. furiosus soluble hydrogenase I (SHI). First, we produced an active recombinant form of SHI in E. coli by the co-expression of sixteen genes using anaerobically-induced promoters. Second, we genetically-engineered P. furiosus to overexpress SHI by an order of magnitude compared to the wild type strain. Third, we generated the first ‘minimal’ form of SHI, one that contained two rather than four subunits. This dimeric form was stable and active, and directly interacted with a pyruvate-oxidizing enzyme with any intermediate electron carrier. The research resulted in five peer-reviewed publications.

  7. Rate Parameter Distributions for Isobutane Dehydrogenation and Isobutene Dimerization and Desorption over HZSM-5

    Directory of Open Access Journals (Sweden)

    Trevor C. Brown

    2013-11-01

    Full Text Available Deconvolution of the evolved isobutene data obtained from temperature-programmed, low-pressure steady-state conversion of isobutane over HZSM-5 has yielded apparent activation energies for isobutane dehydrogenation, isobutene dimerization and desorption. Intrinsic activation energies and associated isobutane collision frequencies are also estimated. A combination of wavelet shrinkage denoising, followed by time-varying flexible least squares of the evolved mass-spectral abundance data over the temperature range 150 to 450 °C, provides accurate, temperature-dependent, apparent rate parameters. Intrinsic activation energies for isobutane dehydrogenation range from 86 to 235.2 kJ mol−1 (average = 150 ± 42 kJ mol−1 for isobutene dimerization from 48.3 to 267 kJ mol−1 (average = 112 ± 74 kJ mol−1 and for isobutene desorption from 64.4 to 97.8 kJ mol−1 (average = 77 ± 12 kJ mol−1. These wide ranges reflect the heterogeneity and acidity of the zeolite surface and structure. Seven distinct locations and sites, including Lewis and Brønsted acid sites can be identified in the profiles. Isobutane collision frequencies range from 10−0.4 to 1022.2 s−1 and are proportional to the accessibility of active sites, within the HZSM-5 micropores or on the external surface.

  8. Universal characteristic function of an adsorption-desorption process

    Institute of Scientific and Technical Information of China (English)

    HE; Chunshan(何春山); FANG; Hai(方海); LI; Zhibing(李志兵)

    2003-01-01

    The characteristic function of the initial order for the adsorption-desorption process is obtained by Monte Carlo simulation. The universality of the generalized scaling relation is confirmed by use of the sequential and synchronous dynamic rules. In the off-critical regime, we observe a "finger-print effect"of the initial state.

  9. Equilibrium adsorption data from temperature-programmed desorption experiments

    NARCIS (Netherlands)

    Foeth, Frank; Mugge, José; Vaart, van der Rick; Bosch, Hans; Reith, Tom

    1996-01-01

    This work describes a novel method that enables the calculation of a series of adsorption isotherms basically from a single Temperature-Programmed Desorption (TPD) experiment. The basic idea is to saturate an adsorbent packed in a fixed bed at a certain feed concentration and temperature and to subs

  10. Thermal Desorption of Helium Implanted in Tungsten at RT

    Institute of Scientific and Technical Information of China (English)

    ZHANGFu; XUZengyu; LIUXiang; CHENJiming; XUYing; N.Yoshida; H.Iwakiri

    2002-01-01

    Tungsten is envisaged as one of the main candidate materials for divertor plate of ITER and future fusion reactors. Due to D-T reaction, PFMs would suffer helium irradiation from plasma additional to the high heat loads. Helium retention and thermal desorption behavior are largely concerned.

  11. Influence of surface coverage on the chemical desorption process

    CERN Document Server

    Marco, Minissale

    2014-01-01

    In cold astrophysical environments, some molecules are observed in the gas phase whereas they should have been depleted, frozen on dust grains. In order to solve this problem, astrochemists have proposed that a fraction of molecules synthesized on the surface of dust grains could desorb just after their formation. Recently the chemical desorption process has been demonstrated experimentally, but the key parameters at play have not yet been fully understood. In this article we propose a new procedure to analyze the ratio of di-oxygen and ozone synthesized after O atoms adsorption on oxidized graphite. We demonstrate that the chemical desorption efficiency of the two reaction paths (O+O and O+O$_2$) is different by one order of magnitude. We show the importance of the surface coverage: for the O+O reaction, the chemical desorption efficiency is close to 80 $\\%$ at zero coverage and tends to zero at one monolayer coverage. The coverage dependence of O+O chemical desorption is proved by varying the amount of pre-...

  12. Quantitative matrix-assisted laser desorption/ionization mass spectrometry

    OpenAIRE

    Duncan, Mark W.; Roder, Heinrich; Hunsucker, Stephen W.

    2008-01-01

    This review summarizes the essential characteristics of matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry (TOF MS), especially as they relate to its applications in quantitative analysis. Approaches to quantification by MALDI-TOF MS are presented and published applications are critically reviewed.

  13. Sorption and desorption of indaziflam degradates in several agricultural soils

    Directory of Open Access Journals (Sweden)

    Diego Gonçalves Alonso

    2016-04-01

    Full Text Available ABSTRACT Processes regulating pesticide fate in the environment are influenced by the physicochemical properties of pesticides and soils. Sorption and desorption are important processes as they regulate the movement of pesticides in soil. Although sorption-desorption is widely studied for herbicides, studies involving their metabolites in soil are scarce. Sorption and desorption of indaziflam metabolites (indaziflam-triazinediamine (FDAT, indaziflam-triazine-indanone (ITI and indaziflam-carboxilic acid (ICA were investigated in six Brazilian (BRA soils and three United States (USA soils with different physicochemical properties. The Freundlich equation described sorption of the metabolites for all soils (R2 > 0.98; 1/n ~ 1. Sorption order (Kf was ITI > ICA > FDAT. Mean values of Kf,oc were 453, 289, and 81 (BRA and 444, 48, and 48 (USA for metabolites ITI, ICA, and FDAT respectively. Desorption was hysteretic for all metabolites in all soils. These results suggest that these metabolites fall in the classification range of mobile to moderately mobile in soils.

  14. [Adsorption and Desorption Characteristics of Endosulfan in Purple Soil].

    Science.gov (United States)

    Zhao, Yan; Zheng, Guo-can; Zhu, Heng; Zhang, Jin-zhong; Zhu, Xiu-ying; Hu, Shu-chun; Wu, Ya-lin

    2015-09-01

    In order to reveal the residual process of endosulfan in purple soil and protect soil ecological environment, the adsorption and desorption characteristics of endosulfan in purple soil were investigated, and effects of temperature, adsorbent amount, and initial pH of adsorption solution on the adsorption capacity were also examined by static adsorption and desorption experiments. The results showed that the adsorption kinetic process could be well described by the second-order kinetic equation with the initial rate constants of α-, β-endosulfan as 0. 157 and 0. 115 mg.(g.min)-1, respectively. The adsorption thermodynamic process could be well described by the Langmuir isotherm with the maximum adsorption capacities of α-, β-endosulfan as 0. 257 mg . g -1 and 0. 155 mg . g -1, respectively. The adsorption process of endosulfan in purple soil may be an exothermic physicochemical process, and is dominated by physical adsorption. Under the experimental conditions examined in this study, the initial pH of adsorption solution had a relative great influence on the adsorption capacity, whereas the temperature and adsorbent amount had no significant influence. The desorption experiments found that the maximum desorption capacities of α-, β-endosulfan adsorbed in purple soil were 0. 029 mg . g -1 and 0. 017 mg . g -1 at 6 and 4 h, and accounted for 10. 5% and 16. 1% in the maximum adsorption capacities, respectively. PMID:26717711

  15. Organic contaminants in soil, desorption kinetics and microbial degradation

    NARCIS (Netherlands)

    Schlebaum, W.

    1999-01-01

    The availability of organic contaminants in soils or sediments for microbial degradation or removal by physical means (e.g.) soil washing or soil venting) depends on the desorption kinetics of these contaminants from the soil matrix. When the organic contaminants desorb very slow from the soil matri

  16. Desorption electrospray ionization mass spectrometry of intact bacteria

    Science.gov (United States)

    Desorption electrospray ionization (DESI) mass spectrometry (MS) was used to differentiate 7 bacterial species based on their measured DESI-mass spectral profile. Both Gram positive and Gram negative bacteria were tested and included Escherichia coli, Staphyloccocus aureus, Enterococcus sp., Bordete...

  17. Desorption electrospray ionization-mass spectrometry of proteins

    Science.gov (United States)

    Desorption electrospray ionization-mass spectrometry (DESI-MS) was evaluated for the detection of proteins ranging in molecular mass from 12 to 66 kDa. Proteins were uniformly deposited on a solid surface without pretreatment and analyzed with a DESI source coupled to a quadrupole ion trap mass spec...

  18. Synthesis and Hydrogen Desorption Properties of Aluminum Hydrides.

    Science.gov (United States)

    Jeong, Wanseop; Lee, Sang-Hwa; Kim, Jaeyong

    2016-03-01

    Aluminum hydride (AlH3 or alane) is known to store maximum 10.1 wt.% of hydrogen at relatively low temperature (hydrogen desorption are still not clear. To understand the desorption properties of hydrogen in alane, thermodynamically stable α-AlH3 was synthesized by employing an ethereal reaction method. The dependence of pathways on phase formation and the properties of hydrogen evolution were investigated, and the results were compared with the ones for γ-AlH3. It was found that γ-AlH3 requires 10 degrees C higher than that of γ-AlH3 to form, and its decomposition rate demonstrated enhanced endothermic stabilities. For desorption, all hydrogen atoms of alane evolved under an isothermal condition at 138 degrees C in less than 1 hour, and the sample completely transformed to pure aluminum. Our results show that the total amount of desorbed hydrogen from α-AlH3 exceeded 9.05 wt.%, with a possibility of further increase. Easy synthesis, thermal stability, and a large amount of hydrogen desorption of alane fulfill the requirements for light-weight hydrogen storage materials once the pathway of hydrogen cycling is provided.

  19. Airborne laser-spark for ambient desorption/ionisation.

    Science.gov (United States)

    Bierstedt, Andreas; Riedel, Jens

    2016-01-01

    A novel direct sampling ionisation scheme for ambient mass spectrometry is presented. Desorption and ionisation are achieved by a quasi-continuous laser induced plasma in air. Since there are no solid or liquid electrodes involved the ion source does not suffer from chemical interferences or fatigue originating from erosive burning or from electrode consumption. The overall plasma maintains electro-neutrality, minimising charge effects and accompanying long term drift of the charged particles trajectories. In the airborne plasma approach the ambient air not only serves as the plasma medium but at the same time also slows down the nascent ions via collisional cooling. Ionisation of the analyte molecules does not occur in the plasma itself but is induced by interaction with nascent ionic fragments, electrons and/or far ultraviolet photons in the plasma vicinity. At each individual air-spark an audible shockwave is formed, providing new reactive species, which expands concentrically and, thus, prevents direct contact of the analyte with the hot region inside the plasma itself. As a consequence the interaction volume between plasma and analyte does not exceed the threshold temperature for thermal dissociation or fragmentation. Experimentally this indirect ionisation scheme is demonstrated to be widely unspecific to the chemical nature of the analyte and to hardly result in any fragmentation of the studied molecules. A vast ensemble of different test analytes including polar and non-polar hydrocarbons, sugars, low mass active ingredients of pharmaceuticals as well as natural biomolecules in food samples directly out of their complex matrices could be shown to yield easily accessible yet meaningful spectra. Since the plasma medium is humid air, the chemical reaction mechanism of the ionisation is likely to be similar to other ambient ionisation techniques. Wir stellen hier eine neue Ionisationsmethode für die Umgebungsionisation (ambient ionisation) vor. Sowohl die

  20. 殊异韦荣菌中乳酸脱氢酶重组蛋白的表达、纯化及活性分析%The recombinant expression, purification and activity analysis of lactate dehydrogenase in Veillonella dispar

    Institute of Scientific and Technical Information of China (English)

    何钟勤; 钟丞; 高心; 薛莹; 孙晓宇; 刘晓红

    2012-01-01

    Objective To determine dependence lactate dehydrogenase activity in Veillonella dispar.Methods Transformed the recombinant plasmid pET-28a-LDH in BL21 (DE3) and Rosetta(DE3).Recombinant lactate dehydrogenase(LDH) protein was induced at different conditions.Induction condition was optimized to obtain proper yield of recombinant protein.After purification by HisTRAP FF column,the protein activity was determined with LDH reactive kit.Results Sodium dodecylsulfate-polyacrylamide gel electrophoresis showed that the best protein expression conditions were isopropylthio-β-D-galactoside (IPTG)end for 0.4 mmol/L concentration in 30 degrees to induce 8 hours,or IPTG end for 0.4 mmol/L concentration in 30 degrees to induce 6 hours.Through the analysis of BandScan 5.0,the expression in BL21 (DE3) was 9.0%,higher than 6.1% in Rosetta(DE3).After purification by HisTRAP FF column,the protein active value of 13.79.Conclusions Recombinant LDH protein could be induced by IPTG with an optimal condition.%目的 进一步测定殊异韦荣菌中依赖性乳酸脱氢酶(lactate dehydrogenase,LDH)的活性,以期为研究该酶的具体功能及作用机制奠定基础,并为龋病预防和治疗提供新的思路.方法 重组质粒转入大肠杆菌BL21(DE3)和Rosetta(DE3)中,采用不同时间及6种不同浓度的异丙基硫代-β-D-半乳糖苷(isopropyhhio-β-D-galactoside,IPTG)诱导乳酸脱氢酶蛋白表达,选择最佳条件诱导LDH蛋白表达.并经His-标记蛋白纯化柱(HisTRAP FF柱)提纯,用LDH活性试剂盒测定蛋白活性.结果 pET-28a-LDH转入BL21(DE3)和Rosetta(DE3)中十二烷基硫酸钠-聚丙烯酰胺凝胶电泳显示最适表达条件分别为IPTG终浓度0.4 mmol/L、30℃诱导8h,IPTG终浓度0.4 mmol/L、30 ℃诱导6h.经BandScan 5.0软件分析,pET-28a-LDH质粒转化BL21(DE3)表达相对含量为9.0%,高于Rosetta(DE3)的6.1%;LDH活性试剂盒测定的蛋白活性值为13.79.结论 本项研究获得了LDH蛋白的最适诱导条