Sample records for airborne alpha activity

  1. Gross alpha, gross beta activities and gamma emitting radionuclides composition of airborne particulate samples in an oceanic island

    NASA Astrophysics Data System (ADS)

    Hernández, F.; Hernández-Armas, J.; Catalán, A.; Fernández-Aldecoa, J. C.; Karlsson, L.

    The radiometric compositions of airborne particulate samples, collected weekly during a 4 years period (1 January 2000 till 31 December 2003) at a site located 310 m a.s.l. in Tenerife (Canary Islands), are analysed in this paper. To do this, measurements of gross alpha, gross beta, 7Be, 210Pb, 228Ac, 226Ra, 212Pb, 214Pb, 208Tl, 214Bi, 235U, 40K, 131I and 137Cs concentrations were carried out in 376 cellulose and polypropylene filters. The time variations of the different radionuclides concentrations have been discussed in relation with various meteorological factors and the mean values have been compared to those published in recent literature for other sites located at the same altitude but different latitudes. The weekly activities of 7Be correlated linearly with the 210Pb activities ( R=0.59). In disagreement with other published studies, the 7Be activities did not correlate ( R=-0.05) with the temperature and maximum values were not found during summer season. The gross beta activities showed correlations with the gross alpha ( R=0.72) and 210Pb activities ( R=0.52), but not with the 7Be ( R=0.16). The anthropogenic radionuclide 131I, emitted from a nearby hospital, was detected slightly above detection limits (1.73×10 -6 Bq m -3) in 88 of the 210 weeks of measurement considered in this work. 137Cs was detected in 31 of those weeks. The 4-year average calculated for 7Be and 210Pb were 3 and 0.3 mBq m -3, respectively. These values are lower than those expected for a site at comparable latitude and altitude. In general, the radionuclides which appeared most frequently in the airborne particulate filters ( 7Be, 210Pb, 212Pb and 40K), did not correlate significantly with any of the meteorological parameters considered: rainfall, temperature, pressure, relative humidity, visibility, wind speed and direction. Therefore, no predictive model could be established with the available data as it has been done for continental sites. The long-range transport of aerosols

  2. Sensitivities of five alpha continuous air monitors for detection of airborne sup 239 Pu

    SciTech Connect

    McIsaac, C.V.; Amaro, C.R.


    Results of measurements of the sensitivities of five alpha continuous air monitors (CAMs) for detection of airborne {sup 239}Pu are presented. Four commercially available alpha CAMs (Kurz model 8311, Merlin Gerin Edgar, RADeCO model 452, and Victoreen model 758) and a prototype alpha CAM currently in use at Argonne National Laboratory- West (ANL-W) were tested sampling natural ambient air and laboratory-generated atmospheres laden with either blank dust or dust containing nCi/g concentrations of {sup 239}Pu. Cumulative alpha spectra were stored at 30 or 60 minute intervals during each sampling and were subsequently analyzed using three different commonly used alpha spectrum analysis algorithms. The effect of airborne dust concentration and sample filter porosity on detector resolution and sensitivity for airborne {sup 239}Pu are described.

  3. Sensitivities of five alpha continuous air monitors for detection of airborne {sup 239}Pu

    SciTech Connect

    McIsaac, C.V.; Amaro, C.R.


    Results of measurements of the sensitivities of five alpha continuous air monitors (CAMs) for detection of airborne {sup 239}Pu are presented. Four commercially available alpha CAMs (Kurz model 8311, Merlin Gerin Edgar, RADeCO model 452, and Victoreen model 758) and a prototype alpha CAM currently in use at Argonne National Laboratory- West (ANL-W) were tested sampling natural ambient air and laboratory-generated atmospheres laden with either blank dust or dust containing nCi/g concentrations of {sup 239}Pu. Cumulative alpha spectra were stored at 30 or 60 minute intervals during each sampling and were subsequently analyzed using three different commonly used alpha spectrum analysis algorithms. The effect of airborne dust concentration and sample filter porosity on detector resolution and sensitivity for airborne {sup 239}Pu are described.

  4. Antimicrobial activity of Nerolidol and its derivatives against airborne microbes and further biological activities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nerolidol and its derivatives, namely cis-nerolidol, O-methyl-nerolidol, O-ethyl-nerolidol, (-)-alpha-bisabolol, trans,trans-farnesol and its main natural source Cabreuva essential oil, were tested for their antimicrobial activity against airborne microbes and antifungal properties against plant pat...

  5. Active airborne contamination control using electrophoresis

    SciTech Connect

    Veatch, B.D.


    In spite of our best efforts, radioactive airborne contamination continues to be a formidable problem at many of the Department of Energy (DOE) weapons complex sites. For workers that must enter areas with high levels of airborne contamination, personnel protective equipment (PPE) can become highly restrictive, greatly diminishing productivity. Rather than require even more restrictive PPE for personnel in some situations, the Rocky Flats Plant (RFP) is actively researching and developing methods to aggressively combat airborne contamination hazards using electrophoretic technology. With appropriate equipment, airborne particulates can be effectively removed and collected for disposal in one simple process. The equipment needed to implement electrophoresis is relatively inexpensive, highly reliable, and very compact. Once airborne contamination levels are reduced, less PPE is required and a significant cost savings may be realized through decreased waste and maximized productivity. Preliminary ``cold,`` or non-radioactive, testing results at the RFP have shown the technology to be effective on a reasonable scale, with several potential benefits and an abundance of applications.

  6. Development of a real-time monitor for airborne alpha emissions. First quarter report, TTP AL 142003

    SciTech Connect

    Gritzo, R.E.; Fowler, M.M.


    This is the first quarterly report for Fiscal Year (FY) 1994 for TTP AL 142003, Development of a Real-Time Monitor for Airborne Alpha Emissions. Los Alamos National Laboratory (LANL) is developing a new technology for on-line, real-time monitoring of incinerator stacks for low levels of airborne alpha activity. While initially developed for incinerators, this new technology may well find other applications in continuous air monitoring, process monitoring, and monitoring during remediation activities. Referred to as the Large-Volume Flow Thru Detector System (LVFTDS), this technology responds directly to the need for fast responding, high sensitivity effluent monitoring systems. With DOE EM-50 funding, LANL has fabricated a bench-top proof of concept detector system and is conducting tests to evaluate its performance. A second- generation prototype is being designed, based on requirements driven by potential field test sites. An industrial partner is being solicited to license the technology. Field trials of a full-scale detector system are planned for FY 95. Accomplishments during the first quarter of FY 94 are chronicled in this report, including budgetary data. A schedule for the remainder of the fiscal year is also provided.

  7. Binding of tumor necrosis factor alpha to activated forms of human plasma alpha 2 macroglobulin.

    PubMed Central

    Wollenberg, G. K.; LaMarre, J.; Rosendal, S.; Gonias, S. L.; Hayes, M. A.


    We tested the hypothesis that human plasma alpha 2 macroglobulin (alpha 2M) is a latent binding glycoprotein for human tumor necrosis factor alpha (TNF-alpha). Human recombinant 125I-TNF-alpha was incubated for 2 hours (37 degrees C) with purified native alpha 2M and with alpha 2M that was modified by reaction with methylamine or various proteinases. 125I-TNF-alpha/alpha 2M complexes were detected by nondenaturing polyacrylamide gel electrophoresis after autoradiography or by liquid chromatography on Superose-6. 125I-TNF-alpha bound strongly but noncovalently to alpha 2M-plasmin and alpha 2M-methylamine. There was minimal binding of 125I-TNF-alpha to native alpha 2M, alpha 2M-trypsin, or alpha 2M-thrombin. A 10(6) molar excess of porcine heparin did not reduce the binding of 125I-TNF-alpha to alpha 2M-methylamine or alpha 2M-plasmin. alpha 2M-plasmin or alpha 2M-methylamine added to human plasma or serum preferentially bound 125I-TNF-alpha in the presence of native alpha 2M. 125I-TNF-alpha also bound to 'fast' alpha-macroglobulins in methylamine-reacted human, rat, mouse, swine, equine, and bovine plasma. However, TNF-alpha, preincubated with either alpha 2M-plasmin or alpha 2M-methylamine, remained a potent necrogen for cultured L929 cells. Purified 125I-TNF-alpha/alpha 2M-plasmin complex injected intravenously in CD-1 mice rapidly cleared from the circulation, unless the alpha 2M-receptor pathway was blocked by coinjection of excess alpha 2M-trypsin. These findings demonstrate that alpha 2M is a latent plasmin-activated binding glycoprotein for TNF-alpha and that TNF-alpha/alpha 2M-plasmin complexes can be removed from the circulation by the alpha 2M-receptor pathway. This suggests that alpha 2M may be an important regulator of the activity and distribution of TNF-alpha in vivo. Images Figure 1 Figure 3 PMID:1704186

  8. Active-passive airborne ocean color measurement. II - Applications

    NASA Technical Reports Server (NTRS)

    Hoge, F. E.; Swift, R. N.; Yungel, J. K.


    Reported here for the first time is the use of a single airborne instrument to make concurrent measurements of oceanic chlorophyll concentration by (1) laser-induced fluorescence, (2) passive upwelling radiance, and (3) solar-induced chlorophyll fluorescence. Results from field experiments conducted with the NASA airborne oceanographic lidar (AOL) in the New York Bight demonstrate the capability of a single active-passive instrument to perform new and potentially important ocean color studies related to (1) active lidar validation of passive ocean color in-water algorithms, (2) chlorophyll a in vivo fluorescence yield variability, (3) calibration of active multichannel lidar systems, (4) effect of sea state on passive and active ocean color measurements, (5) laser/solar-induced chlorophyll fluorescence investigations, and (6) subsequent improvement of satellite-borne ocean color scanners. For validation and comparison purposes a separate passive ocean color sensor was also flown along with the new active-passive sensor during these initial field trials.

  9. Monitoring human and vehicle activities using airborne video

    NASA Astrophysics Data System (ADS)

    Cutler, Ross; Shekhar, Chandra S.; Burns, B.; Chellappa, Rama; Bolles, Robert C.; Davis, Larry S.


    Ongoing work in Activity Monitoring (AM) for the Airborne Video Surveillance (AVS) project is described. The goal for AM is to recognize activities of interest involving humans and vehicles using airborne video. AM consists of three major components: (1) moving object detection, tracking, and classification; (2) image to site-model registration; (3) activity recognition. Detecting and tracking humans and vehicles form airborne video is a challenging problem due to image noise, low GSD, poor contrast, motion parallax, motion blur, and camera blur, and camera jitter. We use frame-to- frame affine-warping stabilization and temporally integrated intensity differences to detect independent motion. Moving objects are initially tracked using nearest-neighbor correspondence, followed by a greedy method that favors long track lengths and assumes locally constant velocity. Object classification is based on object size, velocity, and periodicity of motion. Site-model registration uses GPS information and camera/airplane orientations to provide an initial geolocation with +/- 100m accuracy at an elevation of 1000m. A semi-automatic procedure is utilized to improve the accuracy to +/- 5m. The activity recognition component uses the geolocated tracked objects and the site-model to detect pre-specified activities, such as people entering a forbidden area and a group of vehicles leaving a staging area.

  10. Lucid dreaming and alpha activity: a preliminary report.


    Ogilvie, R D; Hunt, H T; Tyson, P D; Lucescu, M L; Jeakins, D B


    10 good dream recallers spent 2 nights in the sleep lab during which they were awakened 4 times per night from REM sleep, twice during their highest alpha activity in REM, and twice during low REM alpha. 5 were given alpha feedback training prior to sleep onset. Arousals from high alpha REM sleep yielded significantly higher lucidity ratings. Alpha feedback had no effect upon lucidity or REM alpha levels. Similarities between lucid dreams and meditative phenomena are discussed. PMID:7162915

  11. Airborne antituberculosis activity of Eucalyptus citriodora essential oil.


    Ramos Alvarenga, René F; Wan, Baojie; Inui, Taichi; Franzblau, Scott G; Pauli, Guido F; Jaki, Birgit U


    The rapid emergence of multi- and extensively drug-resistant tuberculosis (MDR/XDR-TB) has created a pressing public health problem, which mostly affects regions with HIV/AIDS prevalence and represents a new constraint in the already challenging disease management of tuberculosis (TB). The present work responds to the need to reduce the number of contagious MDR/XRD-TB patients, protect their immediate environment, and interrupt the rapid spread by laying the groundwork for an inhalation therapy based on anti-TB-active constituents of the essential oil (EO) of Eucalyptus citriodora. In order to address the metabolomic complexity of EO constituents and active principles in botanicals, this study applied biochemometrics, a 3-D analytical approach that involves high-resolution CCC fractionation, GC-MS analysis, bioactivity measurements, and chemometric analysis. Thus, 32 airborne anti-TB-active compounds were identified in E. citriodora EO: the monoterpenes citronellol (1), linalool (3), isopulegol (5), and α-terpineol (7) and the sesquiterpenoids spathulenol (11), β-eudesmol (23), and τ-cadinol (25). The impact of the interaction of multiple components in EOs was studied using various artificial mixtures (AMxs) of the active monoterpenes 1, 2, and 5 and the inactive eucalyptol (33). Both neat 1 and the AMx containing 1, 2, and 33 showed airborne TB inhibition of >90%, while the major E. citriodora EO component, 2, was only weakly active, at 18% inhibition. PMID:24641242

  12. Phosphorylation-independent stimulation of DNA topoisomerase II alpha activity.


    Kimura, K; Saijo, M; Tanaka, M; Enomoto, T


    It has been suggested that casein kinase II phosphorylates DNA topoisomerase II alpha (topo II alpha) in mouse FM3A cells, by comparison of phosphopeptide maps of topo II alpha labeled in intact cells and of topo II alpha phosphorylated by various kinases in vitro. The phosphorylation of purified topo II alpha by casein kinase II, which attached a maximum of two phosphate groups per topo II alpha molecule, had no effect on the activity of topo II alpha. Dephosphorylation of purified topo II alpha by potato acid phosphatase, which almost completely dephosphorylated the topo II alpha, did not reduce the activity of topo II alpha. The incubation itself, regardless of phosphorylation or dephosphorylation status, stimulated the enzyme activity in both reactions. Topo II alpha activity was stimulated by incubation in a medium containing low concentrations of glycerol but not in that containing high concentrations of glycerol, such as the 50% in which purified topo II alpha is stored. The stimulation of topo II alpha activity by incubation was dependent on the concentration of topo II alpha, requiring a relatively high concentration of topo II alpha. PMID:8631919

  13. Miniature Neutron-Alpha Activation Spectrometer

    NASA Astrophysics Data System (ADS)

    Rhodes, Edgar; Holloway, James Paul; He, Zhong; Goldsten, John


    We are developing a miniature neutron-alpha activation spectrometer for in-situ analysis of chem-bio samples, including rocks, fines, ices, and drill cores, suitable for a lander or Rover platform for Mars or outer-planet missions. In the neutron-activation mode, penetrating analysis will be performed of the whole sample using a γ spectrometer and in the α-activation mode, the sample surface will be analyzed using Rutherford-backscatter and x-ray spectrometers. Novel in our approach is the development of a switchable radioactive neutron source and a small high-resolution γ detector. The detectors and electronics will benefit from remote unattended operation capabilities resulting from our NEAR XGRS heritage and recent development of a Ge γ detector for MESSENGER. Much of the technology used in this instrument can be adapted to portable or unattended terrestrial applications for detection of explosives, chemical toxins, nuclear weapons, and contraband.

  14. Peroxisome proliferator-activated receptor {alpha}-independent peroxisome proliferation

    SciTech Connect

    Zhang Xiuguo; Tanaka, Naoki . E-mail:; Nakajima, Takero; Kamijo, Yuji; Gonzalez, Frank J.; Aoyama, Toshifumi


    Hepatic peroxisome proliferation, increases in the numerical and volume density of peroxisomes, is believed to be closely related to peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}) activation; however, it remains unknown whether peroxisome proliferation depends absolutely on this activation. To verify occurrence of PPAR{alpha}-independent peroxisome proliferation, fenofibrate treatment was used, which was expected to significantly enhance PPAR{alpha} dependence in the assay system. Surprisingly, a novel type of PPAR{alpha}-independent peroxisome proliferation and enlargement was uncovered in PPAR{alpha}-null mice. The increased expression of dynamin-like protein 1, but not peroxisome biogenesis factor 11{alpha}, might be associated with the PPAR{alpha}-independent peroxisome proliferation at least in part.

  15. Fourth Airborne Geoscience Workshop

    NASA Technical Reports Server (NTRS)


    The focus of the workshop was on how the airborne community can assist in achieving the goals of the Global Change Research Program. The many activities that employ airborne platforms and sensors were discussed: platforms and instrument development; airborne oceanography; lidar research; SAR measurements; Doppler radar; laser measurements; cloud physics; airborne experiments; airborne microwave measurements; and airborne data collection.

  16. Characterization of the airborne activity confinement system prefilter material

    SciTech Connect

    Long, T.A.; Monson, P.R.


    A general concern with assessing the effects of postulated severe accidents is predicting and preventing the release of radioactive isotopes to the environment at the Savannah River Site (SRS) reactor. Unless the confinement systems are breached in an accident the Airborne Activity Confinement System forces all of the internal air through the filter compartments. Proper modeling of the radioactivity released to the environment requires knowledge of the filtering characteristics of the demisters, the HEPA`s, and the charcoal beds. An investigation of the mass loading characteristics for a range of particle sizes was performed under the direction of Vince Novick of Argonne National Laboratory (ANL) for the Savannah River Technology Center (SRTC) in connection with the restart of the K reactor. Both solid and liquid aerosols were used to challenge sample prefilter and HEPA filters. The results of the ANL investigation are reported in this document.

  17. Characterization of the airborne activity confinement system prefilter material

    SciTech Connect

    Long, T.A.; Monson, P.R.


    A general concern with assessing the effects of postulated severe accidents is predicting and preventing the release of radioactive isotopes to the environment at the Savannah River Site (SRS) reactor. Unless the confinement systems are breached in an accident the Airborne Activity Confinement System forces all of the internal air through the filter compartments. Proper modeling of the radioactivity released to the environment requires knowledge of the filtering characteristics of the demisters, the HEPA's, and the charcoal beds. An investigation of the mass loading characteristics for a range of particle sizes was performed under the direction of Vince Novick of Argonne National Laboratory (ANL) for the Savannah River Technology Center (SRTC) in connection with the restart of the K reactor. Both solid and liquid aerosols were used to challenge sample prefilter and HEPA filters. The results of the ANL investigation are reported in this document.

  18. Rapid identification and analysis of airborne plutonium using a combination of alpha spectroscopy and inductively coupled plasma mass spectrometry.


    Farmer, Dennis E; Steed, Amber C; Sobus, Jon; Stetzenbach, Klaus; Lindley, Kaz; Hodge, Vernon F


    Recent wildland fires near two U.S. nuclear facilities point to a need to rapidly identify the presence of airborne plutonium during incidents involving the potential release of radioactive materials. Laboratory turn-around times also need to be shortened for critical samples collected in the earliest stages of radiological emergencies. This note discusses preliminary investigations designed to address both these problems. The methods under review are same day high-resolution alpha spectroscopy to screen air filter samples for the presence of plutonium and inductively coupled plasma mass spectrometry to perform sensitive plutonium analyses. Thus far, using modified alpha spectroscopy techniques, it has been possible to reliably identify the approximately 5.2 MeV emission of 239Pu on surrogate samples (air filters artificially spiked with plutonium after collection) even though the primary alpha-particle emissions of plutonium are, as expected, superimposed against a natural alpha radiation background dominated by short-lived radon and thoron progeny (approximately 6-9 MeV). Several processing methods were tested to prepare samples for analysis and shorten laboratory turn-around time. The most promising technique was acid-leaching of air filter samples using a commercial open-vessel microwave digestion system. Samples prepared in this way were analyzed by both alpha spectroscopy (as a thin-layer iron hydroxide co-precipitate) and inductively coupled plasma mass spectrometry. The detection levels achieved for 239Pu--approximately 1 mBq m(-3) for alpha spectroscopy screening, and, < 0.1 mBq m(-3) for inductively coupled plasma mass spectrometry analysis--are consistent with derived emergency response levels based on EPA's Protective Action Guides, and samples can be evaluated in 36 to 72 h. Further, if samples can be returned to a fixed-laboratory and processed immediately, results from mass spectrometry could be available in as little as 24 h. When fully implemented

  19. Multi-mode multistatics for passive/active airborne surveillance

    NASA Astrophysics Data System (ADS)

    Ogrodnik, Robert F.


    The increasing performance demands for air surveillance assets, as well as the necessity for continued surveillance operations in the presence of enemy jamming anti-radiation missile (ARM) attacks, have increased interest in passive surveillance, in particular multi-mode passive/active multistatic sensing. The use of noncooperative radiation as illuminators of opportunity combined with passive surveillance electromagnetic support measurement (ESM) sensors opens new horizons to multistatic surveillance from a passive airborne platform. Research and field tests have been conducted on ESM augmented bistatics as well as noncooperative multistatics which support the development of airborne multi-mode passive surveillance technology. This work has been conducted under such programs as the Bistatic Enhanced Altimeter Detection (BEAD) and the noncooperative multistatic Passive Coherent Location (PCL). Both BEAD and PCL technology directly support the receiver, signal processing and target location/tracking operations necessary for passive surveillance. The demonstrated technologies for EM interference rejection and multistatic multi-target tracking and location under PCL provide a promising performance bench mark for passive surveillance in the presence of a complex electromagnetic environment. Passive receiver intercept performance under BEAD has provided a receiver design baseline for both look-down and look-up surveillance applications. The technologies under development in BEAD and PCL are presented along with the field test results and the sensor concepts. In particular, spin-off data such as bistatic look-down clutter, noise-floor limitation of noncooperative multistatics and sensitivity limitations set by passive surveillance using signal intercept techniques and illuminators of opportunity are provided.

  20. The activity of granulocyte alpha-amylase in acute appendicitis.


    Zakrzewska, I; Gajda, R


    The activity of alpha-amylase was measured in isolated granulocytes, serum and urine of 35 patients with acute appendicitis. The measurements were performed before operation and on the 7th day after operation. Slightly increased activity of alpha-amylase was found in the serum and urine of 15 patients. On the 7th day after operation the activity of this enzyme reached normal value. The activity of granulocyte alpha-amylase was elevated in 22 patients. In 2 of them the increased activity still maintained on the 7th day after operation. Positive correlation between the serum and granulocyte alpha-amylase activities was found. These observations allow to conclude that granulocytes are the source of increased alpha-amylase activity in the serum of patients with acute appendicitis. PMID:7497089

  1. Reduced Variability of Auditory Alpha Activity in Chronic Tinnitus

    PubMed Central

    Schecklmann, Martin; Kreuzer, Peter M.; Vielsmeier, Veronika; Poeppl, Timm B.; Langguth, Berthold


    Subjective tinnitus is characterized by the conscious perception of a phantom sound which is usually more prominent under silence. Resting state recordings without any auditory stimulation demonstrated a decrease of cortical alpha activity in temporal areas of subjects with an ongoing tinnitus perception. This is often interpreted as an indicator for enhanced excitability of the auditory cortex in tinnitus. In this study we want to further investigate this effect by analysing the moment-to-moment variability of the alpha activity in temporal areas. Magnetoencephalographic resting state recordings of 21 tinnitus subjects and 21 healthy controls were analysed with respect to the mean and the variability of spectral power in the alpha frequency band over temporal areas. A significant decrease of auditory alpha activity was detected for the low alpha frequency band (8–10 Hz) but not for the upper alpha band (10–12 Hz). Furthermore, we found a significant decrease of alpha variability for the tinnitus group. This result was significant for the lower alpha frequency range and not significant for the upper alpha frequencies. Tinnitus subjects with a longer history of tinnitus showed less variability of their auditory alpha activity which might be an indicator for reduced adaptability of the auditory cortex in chronic tinnitus. PMID:24967106

  2. Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

    SciTech Connect

    Lochter, Andre; Navre, Marc; Werb, Zena; Bissell, Mina J


    Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions of integrins during tumor cell invasion.

  3. Neutron activation analysis of airborne thorium liberated during welding operations

    SciTech Connect

    Glasgow, D.C.; Robinson, L.; Janjovic, J.T.


    Typically, reactive metals such as aluminum are welded using a thoriated tungsten welding electrode which is attached to a source of argon gas such that the local atmosphere around the weld is inert. The metal is heated by the arc formed between the electrode and the grounded component to be welded. During this process, some of the electrode is vaporized in the arc and is potentially liberated to the surrounding air. This situation may result in a hazardous airborne thorium level. Because the electrode is consumed during welding, the electrode tip must be repeatedly dressed by grinding the tip to a fine point so that the optimal welding conditions are maintained. These grinding activities may also release thorium to the air. Data generated in the 1950s suggested that these electrodes posed no significant health hazard and seemed to justify their exemption from licensing requirements for source material. Since that time, other studies have been performed and present conflicting results as to the level of risk. Values both above and below the health protection limit in use in the United States, have been reported in the literature recently. This study is being undertaken to provide additional data which may be useful in evaluating both the chemical toxicity risk and radiological dose assessment criteria associated with thoriated tungsten welding operations.

  4. Antimicrobial activity of nerolidol and its derivatives against airborne microbes and further biological activities.


    Krist, Sabine; Banovac, Daniel; Tabanca, Nurhayat; Wedge, David E; Gochev, Velizar K; Wanner, Jürgen; Schmidt, Erich; Jirovetz, Leopold


    Nerolidol and its derivatives, namely cis-nerolidol, O-methyl-nerolidol, O-ethyl-nerolidol, (-)-α-bisabolol, trans,trans-farnesol and its main natural source cabreuva essential oil, were tested for their antimicrobial activity against airborne microbes and antifungal properties against plant pathogens. Among the tested compounds, α-bisabolol was the most effective antimicrobial agent and trans,trans-farnesol showed the best antifungal activity. PMID:25920237

  5. A novel self-guided approach to alpha activity training.


    van Boxtel, Geert J M; Denissen, Ad J M; Jäger, Mark; Vernon, David; Dekker, Marian K J; Mihajlović, Vojkan; Sitskoorn, Margriet M


    Fifty healthy participants took part in a double-blind placebo-controlled study in which they were either given auditory alpha activity (8-12Hz) training (N=18), random beta training (N=12), or no training at all (N=20). A novel wireless electrode system was used for training without instructions, involving water-based electrodes mounted in an audio headset. Training was applied approximately at central electrodes. Post-training measurement using a conventional full-cap EEG system revealed a 10% increase in alpha activity at posterior sites compared to pre-training levels, when using the conventional index of alpha activity and a non-linear regression fit intended to model individual alpha frequency. This statistically significant increase was present only in the group that received the alpha training, and remained evident at a 3 month follow-up session, especially under eyes open conditions where an additional 10% increase was found. In an exit interview, approximately twice as many participants in the alpha training group (53%) mentioned that the training was relaxing, compared to those in either the beta (20%) or no training (21%) control groups. Behavioural measures of stress and relaxation were indicative of effects of alpha activity training but failed to reach statistical significance. These results are discussed in terms of a lack of statistical power. Overall, results suggest that self-guided alpha activity training using this novel system is feasible and represents a step forward in the ease of instrumental conditioning of brain rhythms. PMID:22119661

  6. Increased 5. cap alpha. -reductase activity in idiopathic hirsutism

    SciTech Connect

    Serafini, P.; Lobo, R.A.


    In vitro, genital skin 5..cap alpha..-reductase activity (5..cap alpha..-RA) was measured in ten hirsute women with normal androgen levels (idiopathic hirsutism (IH)) and in ten hirsute women with elevated androgen levels (polycystic ovary syndrome (PCO)) in order to determine the influence of secreted androgens on 5..cap alpha..-RA. In vitro 5..cap alpha..-RA was assessed by incubations of skin with /sup 14/C-testosterone (T) for 2 hours, after which steroids were separated and the radioactivity of dihydrotestosterone (DHT) and 5..cap alpha..-androstane 3..cap alpha..-17..beta..-estradiol (3..cap alpha..-diol) in specific eluates were determined. All androgens were normal in IH with the exception of higher levels of 3..cap alpha..-diol glucuronide which were similar to the levels of PCO. The conversion ratio (CR) of T to DHT in IH and PCO were similar, yet significantly greater than the CR of control subjects. The CR of T to 3..cap alpha..-diol in IH and PCO were similar, yet higher than in control subjects. Serum androgens showed no correlation with 5..cap alpha..-RA, while the CR of T to DHT showed a significant positive correlation with the Ferriman and Gallwey score. The increased 5..cap alpha..-RA in IH appears to be independent of serum androgen levels and is, therefore, an inherent abnormality. The term idiopathic is a misnomer, because hirsutism in these patients may be explained on the basis of increased skin 5..cap alpha..-RA.

  7. Transcriptional activity of the human pseudogene psi alpha globin compared with alpha globin, its functional gene counterpart.

    PubMed Central

    Whitelaw, E; Proudfoot, N J


    Transcriptional analysis of the human pseudogene psi alpha globin has revealed the following features: (1) The promoter with a 23 bp deletion between the CCAAT and ATA boxes is functional both in vitro and in vivo, 3 fold and 10 fold less efficient, respectively, than alpha. (2) Both the psi alpha and alpha globin gene promoters are active in the absence of transcriptional enhancers, either a gene-encoded or viral enhancer. (3) The mutated poly(A) addition signal in psi alpha (AATGAA) appears to be completely nonfunctional. This result provides an explanation for the absence of psi alpha transcripts in human erythroid cells. Images PMID:6316269


    EPA Science Inventory

    Gross alpha activity values were calculated with four different alpha emitting radionuclide standard counting efficiencies to see which standard was best for gross alpha activity determinations. Thorium-230, a pure alpha emitter, appeared to be the best standard for gross alpha c...

  9. Low-valent niobium-mediated double activation of C-F/C-H bonds: fluorene synthesis from o-arylated alpha,alpha,alpha-trifluorotoluene derivatives.


    Fuchibe, Kohei; Akiyama, Takahiko


    By the treatment of 0.3 molar amount of NbCl5 and LiAlH4, o-arylated alpha,alpha,alpha-trifluorotoluenes afforded fluorene derivatives in good yields. C-F bonds of the CF3 group and the neighboring ortho C-H bond were doubly activated to give the coupling products. PMID:16448098

  10. Gamma power is phase-locked to posterior alpha activity.


    Osipova, Daria; Hermes, Dora; Jensen, Ole


    Neuronal oscillations in various frequency bands have been reported in numerous studies in both humans and animals. While it is obvious that these oscillations play an important role in cognitive processing, it remains unclear how oscillations in various frequency bands interact. In this study we have investigated phase to power locking in MEG activity of healthy human subjects at rest with their eyes closed. To examine cross-frequency coupling, we have computed coherence between the time course of the power in a given frequency band and the signal itself within every channel. The time-course of the power was calculated using a sliding tapered time window followed by a Fourier transform. Our findings show that high-frequency gamma power (30-70 Hz) is phase-locked to alpha oscillations (8-13 Hz) in the ongoing MEG signals. The topography of the coupling was similar to the topography of the alpha power and was strongest over occipital areas. Interestingly, gamma activity per se was not evident in the power spectra and only became detectable when studied in relation to the alpha phase. Intracranial data from an epileptic subject confirmed these findings albeit there was slowing in both the alpha and gamma band. A tentative explanation for this phenomenon is that the visual system is inhibited during most of the alpha cycle whereas a burst of gamma activity at a specific alpha phase (e.g. at troughs) reflects a window of excitability. PMID:19098986


    EPA Science Inventory

    The current lack of information regarding the impact of O&M activities on the potential for asbestos exposure to building staff and occupants prompted this study. This report presents a statistical evaluation of airborne asbestos data collected before and during an O&M activity i...

  12. Tetrahydro-iso-alpha Acids Antagonize Estrogen Receptor Alpha Activity in MCF-7 Breast Cancer Cells

    PubMed Central

    Lempereur, Maëlle; Majewska, Claire; Brunquers, Amandine; Wongpramud, Sumalee; Valet, Bénédicte; Janssens, Philippe; Dillemans, Monique; Van Nedervelde, Laurence; Gallo, Dominique


    Tetrahydro-iso-alpha acids commonly called THIAA or Tetra are modified hop acids extracted from hop (Humulus lupulus L.) which are frequently used in brewing industry mainly in order to provide beer bitterness and foam stability. Interestingly, molecular structure of tetrahydro-iso-alpha acids is close to a new type of estrogen receptor alpha (ERα) antagonists aimed at disrupting the binding of coactivators containing an LxxLL motif (NR-box). In this work we show that THIAA decreases estradiol-stimulated proliferation of MCF-7 (ERα-positive breast cancer cells). Besides, we show that it inhibits ERα transcriptional activity. Interestingly, this extract fails to compete with estradiol for ERα binding and does not significantly impact the receptor turnover rate in MCF-7 cells, suggesting that it does not act like classical antiestrogens. Hence, we demonstrate that THIAA is able to antagonize ERα estradiol-induced recruitment of the LxxLL binding motif. PMID:27190515

  13. Tetrahydro-iso-alpha Acids Antagonize Estrogen Receptor Alpha Activity in MCF-7 Breast Cancer Cells.


    Lempereur, Maëlle; Majewska, Claire; Brunquers, Amandine; Wongpramud, Sumalee; Valet, Bénédicte; Janssens, Philippe; Dillemans, Monique; Van Nedervelde, Laurence; Gallo, Dominique


    Tetrahydro-iso-alpha acids commonly called THIAA or Tetra are modified hop acids extracted from hop (Humulus lupulus L.) which are frequently used in brewing industry mainly in order to provide beer bitterness and foam stability. Interestingly, molecular structure of tetrahydro-iso-alpha acids is close to a new type of estrogen receptor alpha (ERα) antagonists aimed at disrupting the binding of coactivators containing an LxxLL motif (NR-box). In this work we show that THIAA decreases estradiol-stimulated proliferation of MCF-7 (ERα-positive breast cancer cells). Besides, we show that it inhibits ERα transcriptional activity. Interestingly, this extract fails to compete with estradiol for ERα binding and does not significantly impact the receptor turnover rate in MCF-7 cells, suggesting that it does not act like classical antiestrogens. Hence, we demonstrate that THIAA is able to antagonize ERα estradiol-induced recruitment of the LxxLL binding motif. PMID:27190515

  14. 5. cap alpha. -reductase activity in rat adipose tissue

    SciTech Connect

    Zyirek, M.; Flood, C.; Longcope, C.


    We measured the 5 ..cap alpha..-reductase activity in isolated cell preparations of rat adipose tissue using the formation of (/sup 3/H) dihydrotestosterone from (/sup 3/H) testosterone as an endpoint. Stromal cells were prepared from the epididymal fat pad, perinephric fat, and subcutaneous fat of male rats and from perinephric fat of female rats. Adipocytes were prepared from the epididymal fat pad and perinephric fat of male rats. Stromal cells from the epididymal fat pad and perinephric fat contained greater 5..cap alpha..-reductase activity than did the adipocytes from these depots. Stromal cells from the epididymal fat pad contained greater activity than those from perinephric and subcutaneous depots. Perinephric stromal cells from female rats were slightly more active than those from male rats. Estradiol (10/sup -8/ M), when added to the medium, caused a 90% decrease in 5..cap alpha..-reductase activity. Aromatase activity was minimal, several orders of magnitude less than 5..cap alpha..-reductase activity in each tissue studied.

  15. Activation of peroxisome proliferator-activated receptor-{alpha} enhances fatty acid oxidation in human adipocytes

    SciTech Connect

    Lee, Joo-Young; Hashizaki, Hikari; Goto, Tsuyoshi; Sakamoto, Tomoya; Takahashi, Nobuyuki; Kawada, Teruo


    Highlights: {yields} PPAR{alpha} activation increased mRNA expression levels of adipocyte differentiation marker genes and GPDH activity in human adipocytes. {yields} PPAR{alpha} activation also increased insulin-dependent glucose uptake in human adipocytes. {yields} PPAR{alpha} activation did not affect lipid accumulation in human adipocytes. {yields} PPAR{alpha} activation increased fatty acid oxidation through induction of fatty acid oxidation-related genes in human adipocytes. -- Abstract: Peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) is a key regulator for maintaining whole-body energy balance. However, the physiological functions of PPAR{alpha} in adipocytes have been unclarified. We examined the functions of PPAR{alpha} using human multipotent adipose tissue-derived stem cells as a human adipocyte model. Activation of PPAR{alpha} by GW7647, a potent PPAR{alpha} agonist, increased the mRNA expression levels of adipocyte differentiation marker genes such as PPAR{gamma}, adipocyte-specific fatty acid-binding protein, and lipoprotein lipase and increased both GPDH activity and insulin-dependent glucose uptake level. The findings indicate that PPAR{alpha} activation stimulates adipocyte differentiation. However, lipid accumulation was not changed, which is usually observed when PPAR{gamma} is activated. On the other hand, PPAR{alpha} activation by GW7647 treatment induced the mRNA expression of fatty acid oxidation-related genes such as CPT-1B and AOX in a PPAR{alpha}-dependent manner. Moreover, PPAR{alpha} activation increased the production of CO{sub 2} and acid soluble metabolites, which are products of fatty acid oxidation, and increased oxygen consumption rate in human adipocytes. The data indicate that activation of PPAR{alpha} stimulates both adipocyte differentiation and fatty acid oxidation in human adipocytes, suggesting that PPAR{alpha} agonists could improve insulin resistance without lipid accumulation in adipocytes. The expected

  16. Effect of chemicals on fungal alpha-amylase activity.


    Ali, F S; Abdel-Moneim, A A


    The effect of 8 growth regulators at concentrations of 1,000, 5,000 and 10,000 ppm on the activity of fungal (Aspergillus flavus var. columnaris) alpha-amylase was studied. Indol acetic acid (IAA) and naphthalene acetic acid (NAA) inhibited alpha-amylase activity by 2% and 7% at 1,000 ppm. The other 6 growth regulators, indol butyric acid (IBA), gibberellic acid, cumarin, cycocel (CCC), atonik-G and kylar, did not inhibit but stimulated alpha-amylase activity (0 to 9%) at 1,000 ppm. All growth regulators studied inhibited alpha-amylase activity at 5,000 and 10,000 ppm concentration except kylar. The effect of organic acids and formaldehyde at 0.01, 0.005, and 0.001 M was studied. Acetic acid stimulated alpha-amylase at all concentrations, but formic acid, oxalic acid, lactic acid and citric acid inhibited alpha-amylase activity by 91, 100, 100 and 79%, respectively, at a concentration of 0.01 M, while by 31, 100, 15 and 20%, respectively, at 0.005 M. Formaldehyde induced 7, 3 and 2% inhibition at 0.01, 0.005 and 0.001 M, respectively. At 0.01 M either sorbitol or fructose inhibited alpha-amylase by 8%, Maltose 7%, sucrose 6%, phenol, glucose and galactose each by 5%, ethanol, glycerol, arabinose and sodium benzoate each by 4%, isopropanol and mannitol 1%, but methanol and ammonium citrate dibasic did not inhibit alpha-amylase. The results indicate that CuCl2, SnCl2, AgNO3 and Fe2(SO4)3 were the strongest inhibitors, followed by Cd(C2H3O2), HgCl2, Na2-EDTA, Na2HPO4, and CaCl2 in decreasing order. NaCl, NaBr and Mn SO4 did not inhibit alpha-amylase at concentrations from 10 mM to 0.01 mM. PMID:2515680

  17. Activity of (-)alpha-bisabolol against Leishmania infantum promastigotes.


    Morales-Yuste, M; Morillas-Márquez, F; Martín-Sánchez, J; Valero-López, A; Navarro-Moll, M C


    Many of the drugs used to treat leishmaniasis are associated with numerous adverse effects. Agents of natural origin have shown activity against different parasites. With this background, an in vitro study was conducted on the activity of (-)alpha-bisabolol, the principal component of Chamomilla recutita essential oil, against Leishmania infantum promastigotes, the main species responsible for human leishmaniasis in Spain. At the two highest concentrations tested (1000 and 500mug/ml), (-)alpha-bisabolol and pentamidine (control agent) achieved 100% inhibition of L. infantum promastigote. These in vitro data can be considered promising in support of the therapeutic use of (-)alpha-bisabolol preparations to treat leishmaniasis caused by L. infantum species. PMID:19577452

  18. Somatosensory Anticipatory Alpha Activity Increases to Suppress Distracting Input

    ERIC Educational Resources Information Center

    Haegens, Saskia; Luther, Lisa; Jensen, Ole


    Effective processing of sensory input in daily life requires attentional selection and amplification of relevant input and, just as importantly, attenuation of irrelevant information. It has been proposed that top-down modulation of oscillatory alpha band activity (8-14 Hz) serves to allocate resources to various regions, depending on task…

  19. In vitro anti-inflammatory activities of new steroidal antedrugs: [16alpha,17alpha-d] Isoxazoline and [16alpha,17alpha-d]-3'-hydroxy-iminoformyl isoxazoline derivatives of prednisolone and 9alpha-fluoroprednisolone.


    Park, Kwan-K; Ko, Dong-H; You, Z; Khan, M Omar F; Lee, Henry J


    A series of new anti-inflammatory steroidal antedrugs with C-16,17-isoxazoline ring system were synthesized and their pharmacological activities were evaluated. We reported earlier that these compounds are promising antedrugs based on the results of 5-day rat croton oil ear edema assay. In the present study, most of these compounds showed high binding affinities to the glucocorticoid receptor of liver cytosol. 21-acetyloxy-9alpha-fluoro-11beta-hydroxy-3,20-dioxo-1,4-pregnadieno [16alpha,17alpha-d] isoxazoline (FP-ISO-21AC) and 11beta,21-dihydroxy-9alpha-fluoro-3,20-dioxo-1,4-pregnadieno [16alpha,17alpha-d] isoxazoline (FP-ISO-21OH) were found 5.0-, 5.3-fold more potent than prednisolone, respectively. Inhibitory effects of the antedrugs on the nitric oxide (NO) production were assessed using LPS-stimulated RAW 264.7 murine macrophage cells. All these steroidal antedrugs exhibited concentration-dependent inhibition of NO production, but their relative potencies were lower than prednisolone. In vitro metabolism study in rat plasma showed that FP-ISO-21AC and 21-acetyloxy-9alpha-fluoro-11beta-hydroxy-3,20-dioxo-1,4-pregnadieno [16alpha,17alpha-d]-3'-hydroxyiminoformyl isoxazoline (FP-OXIM-21AC) were hydrolyzed rapidly, with the half-lives of 2.1 and 4.2 min, respectively. The half-lives of FP-ISO-21OH and 11beta,21-dihydroxy-9alpha-fluoro-3,20-dioxo-1,4-pregnadieno [16alpha,17alpha-d]-3'-hydroxyiminoformyl isoxazoline (FP-OXIM-21OH) were 92.2 and 110.2 min, respectively. PMID:16309722

  20. alpha-Tocopheryl phosphate – an active lipid mediator?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The vitamin E (alpha-tocopherol, alphaT) derivative, alpha-tocopheryl phosphate (alphaTP), is detectable in small amounts in plasma, tissues, and cultured cells. Studies done in vitro and in vivo suggest that alphaT can become phosphorylated and alphaTP dephosphorylated, suggesting the existence of ...

  1. Scanning L-Band Active Passive (SLAP) - Recent Results from an Airborne Simulator for SMAP

    NASA Technical Reports Server (NTRS)

    Kim, Edward


    Scanning L-band Active Passive (SLAP) is a recently-developed NASA airborne instrument specially tailored to simulate the new Soil Moisture Active Passive (SMAP) satellite instrument suite. SLAP conducted its first test flights in December, 2013 and participated in its first science campaign-the IPHEX ground validation campaign of the GPM mission-in May, 2014. This paper will present results from additional test flights and science observations scheduled for 2015.

  2. Alpha-band EEG activity in perceptual learning

    PubMed Central

    Bays, Brett C.; Visscher, Kristina M.; Le Dantec, Christophe C.; Seitz, Aaron R.


    In studies of perceptual learning (PL), subjects are typically highly trained across many sessions to achieve perceptual benefits on the stimuli in those tasks. There is currently significant debate regarding what sources of brain plasticity underlie these PL-based learning improvements. Here we investigate the hypothesis that PL, among other mechanisms, leads to task automaticity, especially in the presence of the trained stimuli. To investigate this hypothesis, we trained participants for eight sessions to find an oriented target in a field of near-oriented distractors and examined alpha-band activity, which modulates with attention to visual stimuli, as a possible measure of automaticity. Alpha-band activity was acquired via electroencephalogram (EEG), before and after training, as participants performed the task with trained and untrained stimuli. Results show that participants underwent significant learning in this task (as assessed by threshold, accuracy, and reaction time improvements) and that alpha power increased during the pre-stimulus period and then underwent greater desynchronization at the time of stimulus presentation following training. However, these changes in alpha-band activity were not specific to the trained stimuli, with similar patterns of posttraining alpha power for trained and untrained stimuli. These data are consistent with the view that participants were more efficient at focusing resources at the time of stimulus presentation and are consistent with a greater automaticity of task performance. These findings have implications for PL, as transfer effects from trained to untrained stimuli may partially depend on differential effort of the individual at the time of stimulus processing. PMID:26370167

  3. HIF-1alpha and HIF-2alpha Are Differentially Activated in Distinct Cell Populations in Retinal Ischaemia

    PubMed Central

    Mowat, Freya M.; Luhmann, Ulrich F. O.; Smith, Alexander J.; Lange, Clemens; Duran, Yanai; Harten, Sarah; Shukla, Deepa; Maxwell, Patrick H.; Ali, Robin R.; Bainbridge, James W. B.


    Background Hypoxia plays a key role in ischaemic and neovascular disorders of the retina. Cellular responses to oxygen are mediated by hypoxia-inducible transcription factors (HIFs) that are stabilised in hypoxia and induce the expression of a diverse range of genes. The purpose of this study was to define the cellular specificities of HIF-1alpha and HIF-2alpha in retinal ischaemia, and to determine their correlation with the pattern of retinal hypoxia and the expression profiles of induced molecular mediators. Methodology/Principal Findings We investigated the tissue distribution of retinal hypoxia during oxygen-induced retinopathy (OIR) in mice using the bio-reductive drug pimonidazole. We measured the levels of HIF-1alpha and HIF-2alpha proteins by Western blotting and determined their cellular distribution by immunohistochemistry during the development of OIR. We measured the temporal expression profiles of two downstream mediators, vascular endothelial growth factor (VEGF) and erythropoietin (Epo) by ELISA. Pimonidazole labelling was evident specifically in the inner retina. Labelling peaked at 2 hours after the onset of hypoxia and gradually declined thereafter. Marked binding to Müller glia was evident during the early hypoxic stages of OIR. Both HIF-1alpha and HIF-2alpha protein levels were significantly increased during retinal hypoxia but were evident in distinct cellular distributions; HIF-1alpha stabilisation was evident in neuronal cells throughout the inner retinal layers whereas HIF-2alpha was restricted to Müller glia and astrocytes. Hypoxia and HIF-alpha stabilisation in the retina were closely followed by upregulated expression of the downstream mediators VEGF and EPO. Conclusions/Significance Both HIF-1alpha and HIF-2alpha are activated in close correlation with retinal hypoxia but have contrasting cell specificities, consistent with differential roles in retinal ischaemia. Our findings suggest that HIF-2alpha activation plays a key role in

  4. Diabetes or peroxisome proliferator-activated receptor alpha agonist increases mitochondrial thioesterase I activity in heart

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peroxisome proliferator-activated receptor alpha (PPAR alpha) is a transcriptional regulator of the expression of mitochondrial thioesterase I (MTE-I) and uncoupling protein 3 (UCP3), which are induced in the heart at the mRNA level in response to diabetes. Little is known about the regulation of pr...

  5. Phytol directly activates peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}) and regulates gene expression involved in lipid metabolism in PPAR{alpha}-expressing HepG2 hepatocytes

    SciTech Connect

    Goto, Tsuyoshi; Takahashi, Nobuyuki; Kato, Sota; Egawa, Kahori; Ebisu, Shogo; Moriyama, Tatsuya; Fushiki, Tohru; Kawada, Teruo . E-mail:


    The peroxisome proliferator-activated receptor (PPAR) is one of the indispensable transcription factors for regulating lipid metabolism in various tissues. In our screening for natural compounds that activate PPAR using luciferase assays, a branched-carbon-chain alcohol (a component of chlorophylls), phytol, has been identified as a PPAR{alpha}-specific activator. Phytol induced the increase in PPAR{alpha}-dependent luciferase activity and the degree of in vitro binding of a coactivator, SRC-1, to GST-PPAR{alpha}. Moreover, the addition of phytol upregulated the expression of PPAR{alpha}-target genes at both mRNA and protein levels in PPAR{alpha}-expressing HepG2 hepatocytes. These findings indicate that phytol is functional as a PPAR{alpha} ligand and that it stimulates the expression of PPAR{alpha}-target genes in intact cells. Because PPAR{alpha} activation enhances circulating lipid clearance, phytol may be important in managing abnormalities in lipid metabolism.

  6. Device and method for accurately measuring concentrations of airborne transuranic isotopes


    McIsaac, Charles V.; Killian, E. Wayne; Grafwallner, Ervin G.; Kynaston, Ronnie L.; Johnson, Larry O.; Randolph, Peter D.


    An alpha continuous air monitor (CAM) with two silicon alpha detectors and three sample collection filters is described. This alpha CAM design provides continuous sampling and also measures the cumulative transuranic (TRU), i.e., plutonium and americium, activity on the filter, and thus provides a more accurate measurement of airborne TRU concentrations than can be accomplished using a single fixed sample collection filter and a single silicon alpha detector.

  7. Device and method for accurately measuring concentrations of airborne transuranic isotopes


    McIsaac, C.V.; Killian, E.W.; Grafwallner, E.G.; Kynaston, R.L.; Johnson, L.O.; Randolph, P.D.


    An alpha continuous air monitor (CAM) with two silicon alpha detectors and three sample collection filters is described. This alpha CAM design provides continuous sampling and also measures the cumulative transuranic (TRU), i.e., plutonium and americium, activity on the filter, and thus provides a more accurate measurement of airborne TRU concentrations than can be accomplished using a single fixed sample collection filter and a single silicon alpha detector. 7 figs.

  8. Multiple Binding Modes between HNF4[alpha] and the LXXLL Motifs of PGC-1[alpha] Lead to Full Activation

    SciTech Connect

    Rha, Geun Bae; Wu, Guangteng; Shoelson, Steven E.; Chi, Young-In


    Hepatocyte nuclear factor 4{alpha} (HNF4{alpha}) is a novel nuclear receptor that participates in a hierarchical network of transcription factors regulating the development and physiology of such vital organs as the liver, pancreas, and kidney. Among the various transcriptional coregulators with which HNF4{alpha} interacts, peroxisome proliferation-activated receptor {gamma} (PPAR{gamma}) coactivator 1{alpha} (PGC-1{alpha}) represents a novel coactivator whose activation is unusually robust and whose binding mode appears to be distinct from that of canonical coactivators such as NCoA/SRC/p160 family members. To elucidate the potentially unique molecular mechanism of PGC-1{alpha} recruitment, we have determined the crystal structure of HNF4{alpha} in complex with a fragment of PGC-1{alpha} containing all three of its LXXLL motifs. Despite the presence of all three LXXLL motifs available for interactions, only one is bound at the canonical binding site, with no additional contacts observed between the two proteins. However, a close inspection of the electron density map indicates that the bound LXXLL motif is not a selected one but an averaged structure of more than one LXXLL motif. Further biochemical and functional studies show that the individual LXXLL motifs can bind but drive only minimal transactivation. Only when more than one LXXLL motif is involved can significant transcriptional activity be measured, and full activation requires all three LXXLL motifs. These findings led us to propose a model wherein each LXXLL motif has an additive effect, and the multiple binding modes by HNF4{alpha} toward the LXXLL motifs of PGC-1{alpha} could account for the apparent robust activation by providing a flexible mechanism for combinatorial recruitment of additional coactivators and mediators.

  9. Activating STAT3 Alpha for Promoting Healing of Neurons

    NASA Technical Reports Server (NTRS)

    Conway, Greg


    A method of promoting healing of injured or diseased neurons involves pharmacological activation of the STAT3 alpha protein. Usually, injured or diseased neurons heal incompletely or not at all for two reasons: (1) they are susceptible to apoptosis (cell death); and (2) they fail to engage in axogenesis that is, they fail to re-extend their axons to their original targets (e.g., muscles or other neurons) because of insufficiency of compounds, denoted neurotrophic factors, needed to stimulate such extension. The present method (see figure) of treatment takes advantage of prior research findings to the effect that the STAT3 alpha protein has anti-apoptotic and pro-axogenic properties.

  10. A species of human alpha interferon that lacks the ability to boost human natural killer activity.

    PubMed Central

    Ortaldo, J R; Herberman, R B; Harvey, C; Osheroff, P; Pan, Y C; Kelder, B; Pestka, S


    Most species of recombinant leukocyte interferons (IFN-alpha A, -alpha B, -alpha C, -alpha D, -alpha F, -alpha I, and -alpha K) were capable of boosting human natural killer (NK) activity after a 2-hr treatment of cells at a concentration of 1-80 units/ml. In contrast, recombinant human IFN-alpha J was found to be incapable of augmenting NK activity after exposure of cells for 2 hr to concentrations as high as 10,000 units/ml. This inability of IFN-alpha J to boost NK activity was not complete because, after exposure of cells to a high concentration of IFN-alpha J (10,000 units/ml) for 18 hr, boosting of cytolysis was observed. IFN-alpha J appeared to interact with receptors for IFN on NK cells since it was found to interfere with the boosting of NK activity by other species of IFN-alpha. In contrast to its deficient ability to augment NK activity, IFN-alpha J has potent antiviral and antiproliferative activities. Such extensive dissociation of these biological activities has not been observed previously with any other natural or recombinant IFN species. Thus, this IFN species may be useful for evaluating the relative importance of various biological activities on the therapeutic effects of IFN, for understanding structure-function relationships, and for determining the biochemical pathways related to the various biological effects of IFN. PMID:6589637

  11. The crystal structure of a TL/CD8{alpha}{alpha} complex at 2.1 {angstrom} resolution : implications for modulation of T cell activation and memory.

    SciTech Connect

    Liu, Y.; Xiong, Y.; Naidenko, O. V.; Liu, J.-H.; Zhang, R.; Joachimiak, A.; Kronenberg, M.; Cheroutre, H.; Reinherz, E. L.; Wang, J.-H.; Biosciences Division; Dana-Farber Cancer Inst.; Harvard Medical School; La Jolla Inst. of Allergy and Immunology


    TL is a nonclassical MHC class I molecule that modulates T cell activation through relatively high-affinity interaction with CD8{alpha}{alpha}. To investigate how the TL/CD8{alpha}{alpha} interaction influences TCR signaling, we characterized the structure of the TL/CD8{alpha}{alpha} complex using X-ray crystallography. Unlike antigen-presenting molecules, the TL antigen-binding groove is occluded by specific conformational changes. This feature eliminates antigen presentation, severely hampers direct TCR recognition, and prevents TL from participating in the TCR activation complex. At the same time, the TL/CD8{alpha}{alpha} interaction is strengthened through subtle structure changes in the TL {alpha}3 domain. Thus, TL functions to sequester and redirect CD8{alpha}{alpha} away from the TCR, modifying lck-dependent signaling.

  12. Cortical alpha activity predicts the confidence in an impending action

    PubMed Central

    Kubanek, Jan; Hill, N. Jeremy; Snyder, Lawrence H.; Schalk, Gerwin


    When we make a decision, we experience a degree of confidence that our choice may lead to a desirable outcome. Recent studies in animals have probed the subjective aspects of the choice confidence using confidence-reporting tasks. These studies showed that estimates of the choice confidence substantially modulate neural activity in multiple regions of the brain. Building on these findings, we investigated the neural representation of the confidence in a choice in humans who explicitly reported the confidence in their choice. Subjects performed a perceptual decision task in which they decided between choosing a button press or a saccade while we recorded EEG activity. Following each choice, subjects indicated whether they were sure or unsure about the choice. We found that alpha activity strongly encodes a subject's confidence level in a forthcoming button press choice. The neural effect of the subjects' confidence was independent of the reaction time and independent of the sensory input modeled as a decision variable. Furthermore, the effect is not due to a general cognitive state, such as reward expectation, because the effect was specifically observed during button press choices and not during saccade choices. The neural effect of the confidence in the ensuing button press choice was strong enough that we could predict, from independent single trial neural signals, whether a subject was going to be sure or unsure of an ensuing button press choice. In sum, alpha activity in human cortex provides a window into the commitment to make a hand movement. PMID:26283892

  13. DNA-binding activity of TNF-{alpha} inducing protein from Helicobacter pylori

    SciTech Connect

    Kuzuhara, T. Suganuma, M.; Oka, K.; Fujiki, H.


    Tumor necrosis factor-{alpha} (TNF-{alpha}) inducing protein (Tip{alpha}) is a carcinogenic factor secreted from Helicobacter pylori (H. pylori), mediated through both enhanced expression of TNF-{alpha} and chemokine genes and activation of nuclear factor-{kappa}B. Since Tip{alpha} enters gastric cancer cells, the Tip{alpha} binding molecules in the cells should be investigated. The direct DNA-binding activity of Tip{alpha} was observed by pull down assay using single- and double-stranded genomic DNA cellulose. The surface plasmon resonance assay, indicating an association between Tip{alpha} and DNA, revealed that the affinity of Tip{alpha} for (dGdC)10 is 2400 times stronger than that of del-Tip{alpha}, an inactive Tip{alpha}. This suggests a strong correlation between DNA-binding activity and carcinogenic activity of Tip{alpha}. And the DNA-binding activity of Tip{alpha} was first demonstrated with a molecule secreted from H. pylori.

  14. High-activity barley alpha-amylase by directed evolution.


    Wong, Dominic W S; Batt, Sarah B; Lee, Charles C; Robertson, George H


    Barley alpha-amylase isozyme 2 was cloned into and constitutively secreted by Saccharomyces cervisiae. The gene coding for the wild-type enzyme was subjected to directed evolution. Libraries of mutants were screened by halo formation on starch agar plates, followed by high-throughput liquid assay using dye-labeled starch as the substrate. The concentration of recombinant enzyme in the culture supernatant was determined by immunodetection, and used for the calculation of specific activity. After three rounds of directed evolution, one mutant (Mu322) showed 1000 times the total activity and 20 times the specific activity of the wild-type enzyme produced by the same yeast expression system. Comparison of the amino acid sequence of this mutant with the wild type revealed five substitutions: Q44H, R303K and F325Y in domain A, and T94A and R128Q in domain B. Two of these mutations. Q44H and R303K, result in amino acids highly conserved in cereal alpha-amylases. R303K and F325Y are located in the raw starch-binding fragment of the enzyme molecule. PMID:15635937

  15. Airborne radioactive contamination monitoring

    SciTech Connect

    Whitley, C.R.; Adams, J.R.; Bounds, J.A.; MacArthur, D.W.


    Current technologies for the detection of airborne radioactive contamination do not provide real-time capability. Most of these techniques are based on the capture of particulate matter in air onto filters which are then processed in the laboratory; thus, the turnaround time for detection of contamination can be many days. To address this shortcoming, an effort is underway to adapt LRAD (Long-Range-Alpha-Detection) technology for real-time monitoring of airborne releases of alpa-emitting radionuclides. Alpha decays in air create ionization that can be subsequently collected on electrodes, producing a current that is proportional to the amount of radioactive material present. Using external fans on a pipe containing LRAD detectors, controlled samples of ambient air can be continuously tested for the presence of radioactive contamination. Current prototypes include a two-chamber model. Sampled air is drawn through a particulate filter and then through the first chamber, which uses an electrostatic filter at its entrance to remove ambient ionization. At its exit, ionization that occurred due to the presence of radon is collected and recorded. The air then passes through a length of pipe to allow some decay of short-lived radon species. A second chamber identical to the first monitors the remaining activity. Further development is necessary on air samples without the use of particulate filtering, both to distinguish ionization that can pass through the initial electrostatic filter on otherwise inert particulate matter from that produced through the decay of radioactive material and to separate both of these from the radon contribution. The end product could provide a sensitive, cost-effective, real-time method of determining the presence of airborne radioactive contamination.

  16. Minimal Determinants for Binding Activated G alpha from the Structure of a G alpha i1-Peptide Dimer

    SciTech Connect

    Johnston,C.; Lobanova, E.; Shavkunov, A.; Low, J.; Ramer, J.; Blasesius, R.; Fredericks, Z.; willard, F.; Kuhlman, B.; et al.


    G-Proteins cycle between an inactive GDP-bound state and an active GTP-bound state, serving as molecular switches that coordinate cellular signaling. We recently used phage display to identify a series of peptides that bind G{alpha}subunits in a nucleotide-dependent manner [Johnston, C. A., Willard, F. S., Jezyk, M. R., Fredericks, Z., Bodor, E. T., Jones, M. B., Blaesius, R., Watts, V. J., Harden, T. K., Sondek, J., Ramer, J. K., and Siderovski, D. P. (2005) Structure 13, 1069-1080]. Here we describe the structural features and functions of KB-1753, a peptide that binds selectively to GDP{center_dot}AlF{sub 4{sup -}}- and GTP{gamma}S-bound states of G{alpha}{sup i} subunits. KB-1753 blocks interaction of G{alpha}{sub transducin} with its effector, cGMP phosphodiesterase, and inhibits transducin-mediated activation of cGMP degradation. Additionally, KB-1753 interferes with RGS protein binding and resultant GAP activity. A fluorescent KB-1753 variant was found to act as a sensor for activated G{alpha} in vitro. The crystal structure of KB-1753 bound to G{alpha}{sub i1}-GDP{center_dot}AlF{sub 4{sup -}} reveals binding to a conserved hydrophobic groove between switch II and 3 helices and, along with supporting biochemical data and previous structural analyses, supports the notion that this is the site of effector interactions for G{alpha}i subunits.

  17. Stress affects salivary alpha-Amylase activity in bonobos.


    Behringer, Verena; Deschner, Tobias; Möstl, Erich; Selzer, Dieter; Hohmann, Gottfried


    Salivary alpha-Amylase (sAA) is a starch digesting enzyme. In addition to its function in the context of nutrition, sAA has also turned out to be useful for monitoring sympathetic nervous system activity. Recent studies on humans have found a relationship between intra-individual changes in sAA activity and physical and psychological stress. In studies on primates and other vertebrates, non-invasive monitoring of short-term stress responses is usually based on measurements of cortisol levels, which are indicative of hypothalamic-pituitary-adrenal activity. The few studies that have used both cortisol levels and sAA activity indicate that these two markers may respond differently and independently to different types of stress such that variation in the degree of the activation of different stress response systems might reflect alternative coping mechanisms or individual traits. Here, we present the first data on intra- and inter-individual variation of sAA activity in captive bonobos and compare the results with information from other ape species and humans. Our results indicate that sAA activity in the bonobo samples was significantly lower than in the human samples but within the range of other great ape species. In addition, sAA activity was significantly higher in samples collected at times when subjects had been exposed to stressors (judged by changes in behavioral patterns and cortisol levels) than in samples collected at other times. Our results indicate that bonobos possess functioning sAA and, as in other species, sAA activity is influenced by autonomic nervous system activity. Monitoring sAA activity could therefore be a useful tool for evaluating stress in bonobos. PMID:21945369

  18. Active alignment and vibration control system for a large airborne optical system

    NASA Astrophysics Data System (ADS)

    Kienholz, David A.


    Airborne optical or electro-optical systems may be too large for all elements to be mounted on a single integrating structure, other than the aircraft fuselage itself. An active system must then be used to maintain the required alignment between elements. However the various smaller integrating structures (benches) must still be isolated from high- frequency airframe disturbances that could excite resonances outside the bandwidth of the alignment control system. The combined active alignment and vibration isolation functions must be performed by flight-weight components, which may have to operate in vacuum. A testbed system developed for the Air Force Airborne Laser program is described. The payload, a full-scale 1650-lb simulated bench, is mounted in six degrees- of-freedom to a vibrating platform by a set of isolator- actuators. The mounts utilize a combination of pneumatics and magnetics to perform the dual functions of low-frequency alignment and high-frequency isolation. Test results are given and future directions for development are described.

  19. Mutagenic activity and chemical analysis of airborne particulates collected in Pisa (Italy)

    SciTech Connect

    Vellosi, R.; Fiorio, R.; Rosellini, D.; Bronzetti, G. ); Vannucchi, C.; Ciacchini, G.; Giaconi, V. ); Bianchi, F. )


    In the last few years there has been much concern about the problem connected to the exposure to mutagens present in the environment of industrialized countries. Particularly, the mutagenic activity of airborne particulate matter has been studied by many investigators and correlated with elevated lung cancer mortality rates. In most cases the Salmonella typhimurium/microsome test has been used for these studies. This short-term test, which is the most validated among the short-term genotoxicity tests, provides an important indication on the carcinogenic potential of environmental pollutants. That are complex mixtures containing a wide variety of compounds potentially capable of causing additive, antagonistic or synergistic genotoxic response in living organisms. Several studies have suggested that diverse factors, such as traffic and meteorological conditions, could affect the levels of pollutants in the air. In our work, we have investigated three different areas in Pisa, where the intensity and the kind of the road traffic were different. Airborne particles have been collected during a year and the genotoxic activity has been studied using TA98 and TA100 strains of Salmonella typhimurium. 20 refs., 1 fig., 3 tabs.

  20. Gross alpha and beta activities in tap waters in Eastern Black Sea region of Turkey.


    Damla, N; Cevik, U; Karahan, G; Kobya, A I


    Gross alpha and gross beta activities were determined for 27 different tap water samples collected from Eastern Black Sea region of Turkey. The instrumentation used to count the gross alpha and gross beta activities was a alpha/beta counter of the low background multiple detector type with 10 sample detectors (Berthold LB770). The obtained results showed that natural activity concentrations of alpha- and beta-emitting radionuclides in tap water samples did not exceed WHO and ITS recommended levels. Concentrations ranging from 0.2 mBq/l to 15 mBq/l and from 25.2 mBq/l to 264.4 mBq/l were observed for the gross alpha and gross beta activities, respectively. For all samples the gross beta activities were higher than the corresponding gross alpha activities. PMID:16084570

  1. Synthesis and in vitro activity of some epimeric 20 alpha-hydroxy, 20-oxime and aziridine pregnene derivatives as inhibitors of human 17 alpha-hydroxylase/C17,20-lyase and 5 alpha-reductase.


    Ling, Y Z; Li, J S; Kato, K; Liu, Y; Wang, X; Klus, G T; Marat, K; Nnane, I P; Brodie, A M


    Some epimeric 20-hydroxy, 20-oxime, 16 alpha, 17 alpha-, 17,20- and 20,21-aziridine derivatives of progesterone were synthesized and evaluated as inhibitors of human 17 alpha-hydroxylase/C17,20-lyase (P450(17) alpha) and 5 alpha-reductase (5 alpha-R). The reduction of 16-dehydropregenolone acetate (3a) was reinvestigated. NaBH4 in the presence of CeCl3 gave better stereo-selectivity for 20 beta-ol [20 alpha/20 beta-OH (4 alpha/4 beta) = 1/2.7] than LTBAH or the Meerwein-Pondroff method reported; reduction with Zn in HOAc formed exclusively 20 alpha-ol (4 alpha b). The 20 alpha- and 20 beta-hydroxy-4,16-pregnadien-3-one (9 alpha) and (9 beta) were synthesized from the alcohols 4 alpha b and 4 beta b. Several 20-oxime pregnadienes and 16 alpha, 17 alpha-, 17,20- and 20,21-aziridinyl-5-pregnene derivatives were also synthesized. LiAlH4 reduction of the 16-en-20-oxime (12b) yielded 20 (R)-(13a) and 20(S)-17 alpha,20-aziridine (13b) and 20(R)-17 beta,20-aziridine (14a). Several compounds inhibited the human P450(17) alpha with greater potency than ketoconzole. The 5 alpha-R enzyme assay showed that while (9 alpha) did not have any activity, (9 beta) and (3b) were potent 5 alpha-reductase (IC50 = 21 and 31 nM) inhibitors with activities similar to finasteride. The 20-oximes (17a) and (17b) were potent dual inhibitors for both 5 alpha-R (IC50 = 63 and 115 nM, compared to 33 nM for finasteride) and P450(17) alpha (IC50 = 43 and 25 nM, compared to 78 nM for ketoconazole). PMID:9839000

  2. Automated docking of {alpha}-(1,4)- and {alpha}-(1,6)-linked glucosyl trisaccharides in the glucoamylase active site

    SciTech Connect

    Countinho, P.M.; Reilly, P.J.; Dowd, M.K.


    Low-energy conformers of five {alpha}-(1,4)- and {alpha}-(1,6)-linked glucosyl trisaccharides were flexibly docked into the glucoamylase active site using AutoDock 2.2. To ensure that all significant conformational space was searched, the starting trisaccharide conformers for docking were all possible combinations of the corresponding disaccharide low-energy conformers. All docked trisaccharides occupied subsites {minus}1 and +1 in very similar modes to those of corresponding nonreducing-end disaccharides. For linear substrates, full binding at subsite +2 occurred only when the substrate reducing end was {alpha}-(1,4)-linked, with hydrogen-bonding with the hydroxy-methyl group being the only polar interaction there. Given the absence of other important interactions at this subsite, multiple substrate conformations are allowed. For the one docked branched substrate, steric hindrance in the {alpha}-(1,6)-glycosidic oxygen suggests that the active-site residues have to change position for hydrolysis to occur. Subsite +1 of the glucoamylase active site allows flexibility in binding but, at least in Aspergillus glucoamylases, subsite +2 selectively binds substrates {alpha}-(1,4)-linked between subsites +1 and +2. Enzyme engineering to limit substrate flexibility at subsite +2 could improve glucoamylase industrial properties.

  3. Biological activity profiles of 1alpha,25-dihydroxyvitamin D2, D3, D4, D7, and 24-epi-1alpha,25-dihydroxyvitamin D2.


    Tsugawa, N; Nakagawa, K; Kawamoto, Y; Tachibana, Y; Hayashi, T; Ozono, K; Okano, T


    We have synthesized several 1alpha,25-dihydroxyvitamin D [1alpha,25(OH)2D] derivatives and evaluated their biological activity in terms of their binding affinity for the vitamin D receptor (VDR) and vitamin D-binding protein (DBP), antiproliferative or differentiation-inducing effects on human promyelocytic leukemic HL-60 cells, and transcriptional activity on a rat 25-hydroxyvitamin D3-24-hydroxylase gene promoter, including two vitamin D-responsive elements (VDREs), and human osteocalcin gene promoter, including a VDRE in transfected human osteosarcoma MG-63 cells. Furthermore, human VDR- or retinoic acid X receptor alpha (RXR alpha)-mediated luciferase activities of the derivatives were also measured by a one-hybrid system in human epitheloid carcinoma, cervix HeLa cells and African green monkey kidney CV-1 cells. Binding affinity for VDR, bone-resorbing activity, antiproliferative and cell-differentiating effects, transactivation potencies on target genes and VDR- or RXR alpha-mediated gene regulations of 1alpha,25(OH)2D2 and 1alpha,25(OH)2D4 were almost comparable to the effects of 1alpha,25(OH)2D3 while 24-epi-1alpha,25(OH)2D2 and 1alpha,25(OH)2D7 were much less active than 1alpha,25(OH)2D3 in these respects. This is the first report concerning biological assessment of 1alpha,25(OH)2D2, 1alpha,25(OH)2D3, 1alpha,25(OH)2D4, 24-epi-1alpha,25(OH)2D2 and 1alpha,25(OH)2D7 at the molecular level, especially with regards to the structural differences at the 24R- or 24S-methyl group and a double bond between carbons 22 and 23 in the side chain of 1alpha,25(OH)2D derivatives. PMID:10328556

  4. Characterization of airborne ice-nucleation-active bacteria and bacterial fragments

    NASA Astrophysics Data System (ADS)

    Šantl-Temkiv, Tina; Sahyoun, Maher; Finster, Kai; Hartmann, Susan; Augustin-Bauditz, Stefanie; Stratmann, Frank; Wex, Heike; Clauss, Tina; Nielsen, Niels Woetmann; Sørensen, Jens Havskov; Korsholm, Ulrik Smith; Wick, Lukas Y.; Karlson, Ulrich Gosewinkel


    Some bacteria have the unique capacity of synthesising ice-nucleation-active (INA) proteins and exposing them at their outer membrane surface. As INA bacteria enter the atmosphere, they may impact the formation of clouds and precipitation. We studied members of airborne bacterial communities for their capacity to catalyse ice formation and we report on the excretion of INA proteins by airborne Pseudomonas sp. We also observed for the first time that INA biological fragments <220 nm were present in precipitation samples (199 and 482 INA fragments per L of precipitation), which confirms the presence of submicron INA biological fragments in the atmosphere. During 14 precipitation events, strains affiliated with the genus Pseudomonas, which are known to carry ina genes, were dominant. A screening for INA properties revealed that ∼12% of the cultivable bacteria caused ice formation at ≤-7 °C. They had likely been emitted to the atmosphere from terrestrial surfaces, e.g. by convective transport. We tested the ability of isolated INA strains to produce outer membrane vesicles and found that two isolates could do so. However, only very few INA vesicles were released per INA cell. Thus, the source of the submicron INA proteinaceous particles that we detected in the atmosphere remains to be elucidated.

  5. ATLAS: an airborne active linescan system for high-resolution topographic mapping

    NASA Astrophysics Data System (ADS)

    Willetts, David V.; Kightley, Peter J.; Mole, S. G.; Pearson, Guy N.; Pearson, P.; Coffey, Adrian S.; Stokes, Tim J.; Tapster, Paul R.; Westwood, M.


    High resolution ground mapping is of interest for survey and management of long linear features such as roads, railways and pipelines, and for georeferencing of areas such as flood plains for hydrological purposes. ATLAS (Airborne Topographic Laser System) is an active linescan system operating at the eyesafe wavelength of 1.5μm. Built for airborne survey, it is currently certified for use on a Twin Squirrel helicopter for operation from low levels to heights above 500 feet allowing commercial survey in built up areas. The system operates at a pulse repetition frequency of 56kHz with a line completed in 15ms, giving 36 points/m2 at the surface at the design flight speed. At each point the range to the ground is measured together with the scan angle of the system. This data is combined with a system attitude measurement from an integrated inertial navigation system and with system position derived from differential GPS data aboard the platform. A recording system captures the data with a synchronised time-stamp to enable post-processed reconstruction of a cloud of data points that will give a three-dimensional representation of the terrain, allowing the points to be located with respect to absolute Earth referenced coordinates to a precision of 5cm in three axes. This paper summarises the design, harmonisation, evaluation and performance of the system, and shows examples of survey data.

  6. Suppression of integrin activation by the membrane-distal sequence of the integrin alphaIIb cytoplasmic tail.

    PubMed Central

    Yamanouchi, Jun; Hato, Takaaki; Tamura, Tatsushiro; Fujita, Shigeru


    Integrin cytoplasmic tails regulate integrin activation including an increase in integrin affinity for ligands. Although there is ample evidence that the membrane-proximal regions of the alpha and beta tails interact with each other to maintain integrins in a low-affinity state, little is known about the role of the membrane-distal region of the alpha tail in regulation of integrin activation. We report a critical sequence for regulation of integrin activation in the membrane-distal region of the alphaIIb tail. Alanine substitution of the RPP residues in the alphaIIb tail rendered alphaIIbbeta3 constitutively active in a metabolic energy-dependent manner. Although an alphaIIb/alpha6Abeta3 chimaeric integrin, in which the alphaIIb tail was replaced by the alpha6A tail, was in an energy-dependent active state to bind soluble ligands, introduction of the RPP sequence into the alpha6A tail inhibited binding of an activation-dependent antibody PAC1. In alphaIIb/alpha6Abeta3, deleting the TSDA sequence from the alpha6A tail or single amino acid substitutions of the TSDA residues inhibited alphaIIb/alpha6Abeta3 activation and replacing the membrane-distal region of the alphaIIb tail with TSDA rendered alphaIIbbeta3 active, suggesting a stimulatory role of TSDA in energy-dependent integrin activation. However, adding TSDA to the alphaIIb tail containing the RPP sequence of the membrane-distal region failed to activate alphaIIbbeta3. These results suggest that the RPP sequence after the GFFKR motif of the alphaIIb tail suppresses energy-dependent alphaIIbbeta3 activation. These findings provide a molecular basis for the regulation of energy-dependent integrin activation by alpha subunit tails. PMID:14723599

  7. In vitro transcriptional activation by a metabolic intermediate: activation by Leu3 depends on alpha-isopropylmalate.


    Sze, J Y; Woontner, M; Jaehning, J A; Kohlhaw, G B


    In the absence of the leucine biosynthetic precursor alpha-isopropylmalate (alpha-IPM), the yeast LEU3 protein (Leu3p) binds DNA and acts as a transcriptional repressor in an in vitro extract. Addition of alpha-IPM resulted in a dramatic increase in Leu3p-dependent transcription. The presence of alpha-IPM was also required for Leu3p to compete effectively with another transcriptional activator, GAL4/VP16, for limiting transcription factors. Therefore, the addition of alpha-IPM appears to convert a transcriptional repressor into an activator. This represents an example in eukaryotes of direct transcriptional regulation by a small effector molecule. PMID:1439822

  8. GW8510 Increases Insulin Expression in Pancreatic Alpha Cells through Activation of p53 Transcriptional Activity

    PubMed Central

    Fomina-Yadlin, Dina; Kubicek, Stefan; Vetere, Amedeo; He, Kaihui Hu; Schreiber, Stuart L.; Wagner, Bridget K.


    Background Expression of insulin in terminally differentiated non-beta cell types in the pancreas could be important to treating type-1 diabetes. Previous findings led us to hypothesize involvement of kinase inhibition in induction of insulin expression in pancreatic alpha cells. Methodology/Principal Findings Alpha (αTC1.6) cells and human islets were treated with GW8510 and other small-molecule inhibitors for up to 5 days. Alpha cells were assessed for gene- and protein-expression levels, cell-cycle status, promoter occupancy status by chromatin immunoprecipitation (ChIP), and p53-dependent transcriptional activity. GW8510, a putative CDK2 inhibitor, up-regulated insulin expression in mouse alpha cells and enhanced insulin secretion in dissociated human islets. Gene-expression profiling and gene-set enrichment analysis of GW8510-treated alpha cells suggested up-regulation of the p53 pathway. Accordingly, the compound increased p53 transcriptional activity and expression levels of p53 transcriptional targets. A predicted p53 response element in the promoter region of the mouse Ins2 gene was verified by chromatin immunoprecipitation (ChIP). Further, inhibition of Jun N-terminal kinase (JNK) and p38 kinase activities suppressed insulin induction by GW8510. Conclusions/Significance The induction of Ins2 by GW8510 occurred through p53 in a JNK- and p38-dependent manner. These results implicate p53 activity in modulation of Ins2 expression levels in pancreatic alpha cells, and point to a potential approach toward using small molecules to generate insulin in an alternative cell type. PMID:22242153

  9. Honey Bees (Apis mellifera, L.) as Active Samplers of Airborne Particulate Matter

    PubMed Central

    Di Prisco, Gennaro; Caprio, Emilio; Pellecchia, Marco


    Honey bees (Apis mellifera L.) are bioindicators of environmental pollution levels. During their wide-ranging foraging activity, these hymenopterans are exposed to pollutants, thus becoming a useful tool to trace the environmental contaminants as heavy metals, pesticides, radionuclides and volatile organic compounds. In the present work we demonstrate that bees can also be used as active samplers of airborne particulate matter. Worker bees were collected from hives located in a polluted postmining area in South West Sardinia (Italy) that is also exposed to dust emissions from industrial plants. The area is included in an official list of sites of national interest for environmental remediation, and has been characterized for the effects of pollutants on the health of the resident population. The head, wings, hind legs and alimentary canal of the bees were investigated with Scanning Electron Microscopy coupled with X-ray spectroscopy (SEM-EDX). The analyses pointed to specific morphological and chemical features of the particulate, and resulted into the identification of three categories of particles: industry -, postmining -, and soil –derived. With the exception of the gut, all the analyzed body districts displayed inorganic particles, mostly concentrated in specific areas of the body (i.e. along the costal margin of the fore wings, the medial plane of the head, and the inner surface of the hind legs). The role of both past mining activities and the industrial activity close to the study area as sources of the particulate matter is also discussed. We conclude that honey bees are able to collect samples of the main airborne particles emitted from different sources, therefore could be an ideal tool for monitoring such a kind of pollutants. PMID:26147982

  10. Honey Bees (Apis mellifera, L.) as Active Samplers of Airborne Particulate Matter.


    Negri, Ilaria; Mavris, Christian; Di Prisco, Gennaro; Caprio, Emilio; Pellecchia, Marco


    Honey bees (Apis mellifera L.) are bioindicators of environmental pollution levels. During their wide-ranging foraging activity, these hymenopterans are exposed to pollutants, thus becoming a useful tool to trace the environmental contaminants as heavy metals, pesticides, radionuclides and volatile organic compounds. In the present work we demonstrate that bees can also be used as active samplers of airborne particulate matter. Worker bees were collected from hives located in a polluted postmining area in South West Sardinia (Italy) that is also exposed to dust emissions from industrial plants. The area is included in an official list of sites of national interest for environmental remediation, and has been characterized for the effects of pollutants on the health of the resident population. The head, wings, hind legs and alimentary canal of the bees were investigated with Scanning Electron Microscopy coupled with X-ray spectroscopy (SEM-EDX). The analyses pointed to specific morphological and chemical features of the particulate, and resulted into the identification of three categories of particles: industry-, postmining-, and soil-derived. With the exception of the gut, all the analyzed body districts displayed inorganic particles, mostly concentrated in specific areas of the body (i.e. along the costal margin of the fore wings, the medial plane of the head, and the inner surface of the hind legs). The role of both past mining activities and the industrial activity close to the study area as sources of the particulate matter is also discussed. We conclude that honey bees are able to collect samples of the main airborne particles emitted from different sources, therefore could be an ideal tool for monitoring such a kind of pollutants. PMID:26147982


    EPA Science Inventory


    Aging is associated with alterations in hepatic peroxisomal metabolism and susceptibility to hepatocarcinogenecity produced by agonists of peroxisome proliferator-activated receptor alpha (PPARa). Mechanisms involved in these effects are not well understood. Howev...

  12. Activation of bean (Phaseolus vulgaris) [alpha]-amylase inhibitor requires proteolytic processing of the proprotein

    SciTech Connect

    Pueyo, J.J.; Hunt, D.C.; Chrispeels, M.J. )


    Seeds of the common bean (Phaseolus vulgaris) contain a plant defense protein that inhibits the [alpha]-amylases of mammals and insects. This [alpha]-amylase inhibitor ([alpha]Al) is synthesized as a proprotein on the endoplasmic reticulum and is proteolytically processed after arrival in the protein storage vacuoles to polypeptides of relative molecular weight (M[sub r]) 15,000 to 18,000. The authors report two types of evidence that proteolytic processing is linked to activation of the inhibitory activity. First, by surveying seed extracts of wild accessions of P. vulgaris and other species in the genus Phaseolus, they found that antibodies to [alpha]Al recognize large (M[sub r] 30,000-35,000) polypeptides as well as typical [alpha]Al processing products (M[sub r] 15,000-18,000). [alpha]Al activity was found in all extracts that had the typical [alpha]Al processed polypeptides, but was absent from seed extracts that lacked such polypeptides. Second, they made a mutant [alpha]Al in which asparagine-77 is changed to aspartic acid-77. This mutation slows down the proteolytic processing of pro-[alpha]Al when the gene is expressed in tobacco. When pro-[alpha]Al was separated from mature [alpha]Al by gel filtration, pro-[alpha]Al was found not to have [alpha]-amylase inhibitory activity. The authors interpret these results to mean that formation of the active inhibitor is causally related to proteolytic processing of the proprotein. They suggest that the polypeptide cleavage removes a conformation constraint on the precursor to produce the biochemically active molecule. 43 refs., 5 figs., 1 tab.

  13. Activation of bean (Phaseolus vulgaris) alpha-amylase inhibitor requires proteolytic processing of the proprotein.

    PubMed Central

    Pueyo, J J; Hunt, D C; Chrispeels, M J


    Seeds of the common bean (Phaseolus vulgaris) contain a plant defense protein that inhibits the alpha-amylases of mammals and insects. This alpha-amylase inhibitor (alpha AI) is synthesized as a proprotein on the endoplasmic reticulum and is proteolytically processed after arrival in the protein storage vacuoles to polypeptides of relative molecular weight (M(r)) 15,000 to 18,000. We report two types of evidence that proteolytic processing is linked to activation of the inhibitory activity. First, by surveying seed extracts of wild accessions of P. vulgaris and other species in the genus Phaseolus, we found that antibodies to alpha AI recognize large (M(r) 30,000-35,000) polypeptides as well as typical alpha AI processing products (M(r) 15,000-18,000). Alpha AI activity was found in all extracts that had the typical alpha AI processed polypeptides, but was absent from seed extracts that lacked such polypeptides. Second, we made a mutant alpha AI in which asparagine-77 is changed to aspartic acid-77. This mutation slows down the proteolytic processing of pro-alpha AI when the gene is expressed in tobacco. When pro-alpha AI was separated from mature alpha AI by gel filtration, pro-alpha AI was found not to have alpha-amylase inhibitory activity. We interpret these results to mean that formation of the active inhibitor is causally related to proteolytic processing of the proprotein. We suggest that the polypeptide cleavage removes a conformational constraint on the precursor to produce the biochemically active molecule. PMID:8310064

  14. Conditional expression of constitutively active estrogen receptor {alpha} in chondrocytes impairs longitudinal bone growth in mice

    SciTech Connect

    Ikeda, Kazuhiro; Tsukui, Tohru; Imazawa, Yukiko; Horie-Inoue, Kuniko; Inoue, Satoshi


    Highlights: Black-Right-Pointing-Pointer Conditional transgenic mice expressing constitutively active estrogen receptor {alpha} (caER{alpha}) in chondrocytes were developed. Black-Right-Pointing-Pointer Expression of caER{alpha} in chondrocytes impaired longitudinal bone growth in mice. Black-Right-Pointing-Pointer caER{alpha} affects chondrocyte proliferation and differentiation. Black-Right-Pointing-Pointer This mouse model is useful for understanding the physiological role of ER{alpha}in vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caER{alpha}{sup ColII}, expressing constitutively active mutant estrogen receptor (ER) {alpha} in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caER{alpha}{sup ColII} mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caER{alpha}{sup ColII} mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caER{alpha}{sup ColII} mice. These results suggest that ER{alpha} is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.

  15. Spatial correspondence of brain alpha activity component in fMRI and EEG

    NASA Astrophysics Data System (ADS)

    Jeong, Jeong-Won; Kim, Sung-Heon; Singh, Manbir


    This paper presents a new approach to investigate the spatial correlation of brain alpha activity in functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). To avoid potential problems of simultaneous fMRI and EEG acquisitions in imaging brain alpha activity, data from each modality were acquired separately under a "three conditions" setup where one of the conditions involved closing eyes and relaxing, thus making it conducive to generation of alpha activity. The other two conditions -- eyes open in a lighted room or engaged in a mental arithmetic task, were designed to attenuate alpha activity. Using the Mixture Density Independent Component Analysis (MD-ICA) that incorporates flexible non-linearity functions into the conventional ICA framework, we could identify the spatiotemporal components of fMRI activations and EEG activities associated with the alpha rhythm. The sources of the individual EEG alpha activity component were localized by a Maximum Entropy (ME) method that solves an inverse problem in the framework of a classical four-sphere head model. The resulting dipole sources of EEG alpha activity were spatially transformed to 3D MRIs of the subject and compared to fMRI ICA-determined alpha activity maps.

  16. Hydrolytic activity of alpha-galactosidases against deoxy derivatives of p-nitrophenyl alpha-D-galactopyranoside.


    Hakamata, W; Nishio, T; Oku, T


    The four possible monodeoxy derivatives of p-nitrophenyl (PNP) alpha-D-galactopyranoside were synthesized, and hydrolytic activities of the alpha-galactosidase of green coffee bean, Mortierella vinacea and Aspergillus niger against them were elucidated. The 2- and 6-deoxy substrates were hydrolyzed by the enzymes from green coffee bean and M. vinacea, while they scarcely acted on the 3- and 4-deoxy compounds. On the other hand, A. niger alpha-galactosidase hydrolyzed only the 2-deoxy compound in these deoxy substrates, and the activity was very high. These results indicate that the presence of two hydroxyl groups (OH-3 and -4) is essential for the compounds to act as substrates for the enzymes of green coffee bean and M. vinacea, while the three hydroxyl groups (OH-3, -4, and -6) are necessary for the activity of the A. niger enzyme. The kinetic parameters (K(m) and Vmax) of the enzymes for the hydrolysis of PNP alpha-D-galactopyranoside and its deoxy derivatives were obtained from kinetic studies. PMID:10702877

  17. Alpha-Amylase Activity in Blood Increases after Pharmacological, But Not Psychological, Activation of the Adrenergic System

    PubMed Central

    Nater, Urs M.; La Marca, Roberto; Erni, Katja; Ehlert, Ulrike


    Background & Aim Alpha-amylase in both blood and saliva has been used as a diagnostic parameter. While studies examining alpha-amylase activity in saliva have shown that it is sensitive to physiological and psychological challenge of the adrenergic system, no challenge studies have attempted to elucidate the role of the adrenergic system in alpha-amylase activity in blood. We set out to examine the impact of psychological and pharmacological challenge on alpha-amylase in blood in two separate studies. Methods In study 1, healthy subjects were examined in a placebo-controlled, double-blind paradigm using yohimbine, an alpha2-adrenergic antagonist. In study 2, subjects were examined in a standardized rest-controlled psychosocial stress protocol. Alpha-amylase activity in blood was repeatedly measured in both studies. Results Results of study 1 showed that alpha-amylase in blood is subject to stronger increases after injection of yohimbine compared to placebo. In study 2, results showed that there was no significant effect of psychological stress compared to rest. Conclusions Alpha-amylase in blood increases after pharmacological activation of the adrenergic pathways suggesting that sympathetic receptors are responsible for these changes. Psychological stress, however, does not seem to have an impact on alpha-amylase in blood. Our findings provide insight into the mechanisms underlying activity changes in alpha-amylase in blood in healthy individuals. PMID:26110636

  18. Binding of receptor-recognized forms of alpha2-macroglobulin to the alpha2-macroglobulin signaling receptor activates phosphatidylinositol 3-kinase.


    Misra, U K; Pizzo, S V


    Ligation of the alpha2-macroglobulin (alpha2M) signaling receptor by receptor-recognized forms of alpha2M (alpha2M*) initiates mitogenesis secondary to increased intracellular Ca2+. We report here that ligation of the alpha2M signaling receptor also causes a 1. 5-2.5-fold increase in wortmannin-sensitive phosphatidylinositol 3-kinase (PI3K) activity as measured by the quantitation of phosphatidylinositol 3,4,5-trisphosphate (PIP3). PIP3 formation was alpha2M* concentration-dependent with a maximal response at approximately 50 pM ligand concentration. The peak formation of PIP3 occurred at 10 min of incubation. The alpha2M receptor binding fragment mutant K1370R which binds to the alpha2M signaling receptor activating the signaling cascade, increased PIP3 formation by 2-fold. The mutant K1374A, which binds very poorly to the alpha2M signaling receptor, did not cause any increase in PIP3 formation. alpha2M*-induced DNA synthesis was inhibited by wortmannin. 1, 2Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acetoxymethylester a chelator of intracellular Ca2+, drastically reduced alpha2M*-induced increases in PIP3 formation. We conclude that PI3K is involved in alpha2M*-induced mitogenesis in macrophages and intracellular Ca2+ plays a role in PI3K activation. PMID:9593670

  19. Synthetic method and biological activities of cis-fused alpha-methylene gamma-lactones.


    Higuchi, Yohsuke; Shimoma, Fumito; Ando, Masayoshi


    A reliable method was developed for the synthesis of cis-fused alpha-methylene gamma-lactones via alpha-methyl gamma-lactones. Bromination of alpha-methyl gamma-lactones with LDA/CBr(4) or TMSOTf/PTAB and successive dehydrobromination with DBU or TBAF of the resulting alpha-bromo-alpha-methyl gamma-lactones gave the desired alpha-methylene gamma-lactones in high yield. This method was successfully applied to the synthesis of biologically active compounds. alpha-Methylene gamma-lactone derivatives 1c, 2c, 4c, and 17 showed cell growth inhibitory activity to P388 lymphocytic leukemia. They also showed significant activities to crop diseases. Thus, alpha-methylene gamma-lactone 1c showed preventive activity in controlling scab of apple caused by Venturia inaequalis. alpha-Methylene gamma-lactones 2c, 4c, 17, and 18 also showed significant preventive activities in controlling damping off of cucumber caused by Pythium aphanidermatum. PMID:12828467

  20. Functional characterization of alpha-synuclein protein with antimicrobial activity.


    Park, Seong-Cheol; Moon, Jeong Chan; Shin, Su Young; Son, Hyosuk; Jung, Young Jun; Kim, Nam-Hong; Kim, Young-Min; Jang, Mi-Kyeong; Lee, Jung Ro


    Alpha-synuclein (α-Syn), a small (14 kDa) protein associated with Parkinson's disease, is abundant in human neural tissues. α-Syn plays an important role in maintaining a supply of synaptic vesicles in presynaptic terminals; however, the mechanism by which it performs this function are not well understood. In addition, there is a correlation between α-Syn over-expression and upregulation of an innate immune response. Given the growing body of literature surrounding antimicrobial peptides (AMPs) in the brain, and the similarities between α-Syn and a previously characterized AMP, Amyloid-β, we set out to investigate if α-Syn shares AMP-like properties. Here we demonstrate that α-Syn exhibits antibacterial activity against Escherichia coli and Staphylococcus aureus. In addition, we demonstrate a role for α-Syn in inhibiting various pathogenic fungal strains such as Aspergillus flavus, Aspergillus fumigatus and Rhizoctonia solani. We also analyzed localizations of recombinant α-Syn protein in E. coli and Candida albicans. These results suggest that in addition to α-Syn's role in neurotransmitter release, it appears to be a natural AMP. PMID:27520375

  1. Inhibition of Epstein-Barr virus-mediated capping of CD21/CR2 by alpha interferon (IFN-alpha): immediate antiviral activity of IFN-alpha during the early phase of infection.

    PubMed Central

    Delcayre, A X; Lotz, M; Lernhardt, W


    Early events of human B-lymphocyte infection by Epstein-Barr virus involve the virus binding to CD21, capping, and subsequent internalization of the virus-receptor complex. We show here that alpha interferon (IFN-alpha) inhibits the capping of Epstein-Barr virus-CD21 complexes. Synthetic peptides with the CD21 binding motif of IFN-alpha mimic IFN-alpha activity, suggesting that this effect may be mediated by IFN-alpha-CD21 interaction. Our findings demonstrate a novel and immediate mechanism of IFN-alpha action. PMID:8386282

  2. Activation of peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) suppresses postprandial lipidemia through fatty acid oxidation in enterocytes

    SciTech Connect

    Kimura, Rino; Takahashi, Nobuyuki; Murota, Kaeko; Yamada, Yuko; Niiya, Saori; Kanzaki, Noriyuki; Murakami, Yoko; Moriyama, Tatsuya; Goto, Tsuyoshi; Kawada, Teruo


    Highlights: {yields} PPAR{alpha} activation increased mRNA expression levels of fatty acid oxidation-related genes in human intestinal epithelial Caco-2 cells. {yields} PPAR{alpha} activation also increased oxygen consumption rate and CO{sub 2} production and decreased secretion of triglyceride and ApoB from Caco-2 cells. {yields} Orally administration of bezafibrate increased mRNA expression levels of fatty acid oxidation-related genes and CO{sub 2} production in small intestinal epithelial cells. {yields} Treatment with bezafibrate decreased postprandial serum concentration of triglyceride after oral injection of olive oil in mice. {yields} It suggested that intestinal lipid metabolism regulated by PPAR{alpha} activation suppresses postprandial lipidemia. -- Abstract: Activation of peroxisome proliferator-activated receptor (PPAR)-{alpha} which regulates lipid metabolism in peripheral tissues such as the liver and skeletal muscle, decreases circulating lipid levels, thus improving hyperlipidemia under fasting conditions. Recently, postprandial serum lipid levels have been found to correlate more closely to cardiovascular diseases than fasting levels, although fasting hyperlipidemia is considered an important risk of cardiovascular diseases. However, the effect of PPAR{alpha} activation on postprandial lipidemia has not been clarified. In this study, we examined the effects of PPAR{alpha} activation in enterocytes on lipid secretion and postprandial lipidemia. In Caco-2 enterocytes, bezafibrate, a potent PPAR{alpha} agonist, increased mRNA expression levels of fatty acid oxidation-related genes, such as acyl-CoA oxidase, carnitine palmitoyl transferase, and acyl-CoA synthase, and oxygen consumption rate (OCR) and suppressed secretion levels of both triglycerides and apolipoprotein B into the basolateral side. In vivo experiments revealed that feeding high-fat-diet containing bezafibrate increased mRNA expression levels of fatty acid oxidation-related genes and

  3. 6 alpha-Fluoro- and 6 alpha,9 alpha-difluoro-11 beta,21-dihydroxy-16 alpha,17 alpha-propylmethylenedioxypregn-4-ene-3,20-dione: synthesis and evaluation of activity and kinetics of their C-22 epimers.


    Thalén, B A; Axelsson, B I; Andersson, P H; Brattsand, R L; Nylander, B; Wickström, L I


    It is generally accepted that the anti-inflammatory effect of glucocorticosteroids cannot be separated from their adverse effects at the receptor level. However, modification of the pharmacokinetics through structural alterations could provide steroids with a better therapeutic index than those currently used. Thus, new 16 alpha,17 alpha-acetals between butyraldehyde and 6 alpha-fluoro- or 6 alpha,9 alpha-difluoro-16 alpha-hydroxycortisol were synthesized and studied. Acetalization of the corresponding 16 alpha,17 alpha-diols or transacetalization of their 16 alpha,17 alpha-acetonides in dioxane produced mixtures of C-22 epimers, which were resolved by preparative chromatography. Alternatively, an efficient method was used to produce the 22R-epimer stereoselectively through performing the acetalization and transacetalization in a hydrocarbon with an inert material present. The C-22 configuration of (22R)-6 alpha,9 alpha-difluoro-11 beta,21-dihydroxy-16 alpha,17 alpha-propylmethylenedioxypregn-4-ene-3,20-dione was unambiguously established by single crystal X-ray diffraction. The present compounds, especially the 22R-epimer just mentioned, bind to the rat thymus glucocorticoid receptor with high potency. The C-22 epimers of the 6 alpha,9 alpha-difluoro derivatives showed a 10-fold higher biotransformation rate than the budesonide 22R-epimer when incubated with human liver S9 subcellular fraction. The high receptor affinity in combination with the high biotransformation rate indicates that (22R)-6 alpha,9 alpha-difluoro-11 beta,21-dihydroxy-16 alpha,17 alpha-propylmethylenedioxypregn-4-ene-3,20-dione may be an improved 16 alpha,17 alpha-acetal glucocorticosteroid for therapy of inflammatory diseases, in which the mucous membranes are involved, such as those in the intestinal tract as well in the respiratory tract. PMID:9437793

  4. Interferon-alpha stimulates production of interleukin-10 in activated CD4+ T cells and monocytes.


    Aman, M J; Tretter, T; Eisenbeis, I; Bug, G; Decker, T; Aulitzky, W E; Tilg, H; Huber, C; Peschel, C


    In the present study, we investigated the effect of interferon-alpha (IFN-alpha) on the expression of interleukin-10 (IL-10) mRNA and protein synthesis in human monocytes and CD4+ T cells. In mononuclear cells, IFN-alpha induced expression of IL-10 mRNA and further enhanced lipopolysaccharide (LPS)-stimulated IL-10 expression. In purified monocytes, a strong expression of IL-10 mRNA induced by LPS was not further enhanced by IFN-alpha. In highly purified CD4+ T cells, IFN-alpha upregulated IL-10 mRNA upon activation with phytohemagglutinin and phorbol myristate acetate. In purified monocytes, an effect of IFN-alpha on IL-10 protein synthesis was dependent on costimulation with LPS. Maximal stimulation of IL-10 protein by IFN-alpha was seen after prolonged incubation periods of 48 to 96 hours, whereas IFN-gamma reduced IL-10 production in the early incubation period. Similar effects of IFN-alpha were observed in CD4+ T cells activated with CD3 and CD28 monoclonal antibodies. Addition of IFN-alpha caused an increase of IL-10 in culture supernatants of activated T-helper cells of more than 100% after 96 hours of incubation. In contrast, other cytokines, including IFN-gamma and IL-4, had no influence on IL-10 secretion stimulated by CD3 and CD28 in CD4+ T cells. In serum samples of IFN-alpha-treated individuals, we failed to detect an influence of cytokine treatment on IL-10 serum levels, confirming the requirement of additional activating signals for IFN-alpha-mediated effects on IL-10 synthesis. In conclusion, IFN-alpha enhances the late induction of IL-10, which physiologically occurs upon stimulation of monocytes and T cells. Biologically, this effect might enhance the negative-feedback mechanism ascribed to IL-10, which limits inflammatory reactions. PMID:8639843

  5. Phosphorylation regulates the water channel activity of the seed-specific aquaporin alpha-TIP.


    Maurel, C; Kado, R T; Guern, J; Chrispeels, M J


    The vacuolar membrane protein alpha-TIP is a seed-specific protein of the Major Intrinsic Protein family. Expression of alpha-TIP in Xenopus oocytes conferred a 4- to 8-fold increase in the osmotic water permeability (Pf) of the oocyte plasma membrane, showing that alpha-TIP forms water channels and is thus a new aquaporin. alpha-TIP has three putative phosphorylation sites on the cytoplasmic side of the membrane (Ser7, Ser23 and Ser99), one of which (Ser7) has been shown to be phosphorylated. We present several lines of evidence that the activity of this aquaporin is regulated by phosphorylation. First, mutation of the putative phosphorylation sites in alpha-TIP (Ser7Ala, Ser23Ala and Ser99Ala) reduced the apparent water transport activity of alpha-TIP in oocytes, suggesting that phosphorylation of alpha-TIP occurs in the oocytes and participates in the control of water channel activity. Second, exposure of oocytes to the cAMP agonists 8-bromoadenosine 3',5'-cyclic monophosphate, forskolin and 3-isobutyl-1-methylxanthine, which stimulate endogenous protein kinase A (PKA), increased the water transport activity of alpha-TIP by 80-100% after 60 min. That the protein can be phosphorylated by PKA was demonstrated by phosphorylating alpha-TIP in isolated oocyte membranes with the bovine PKA catalytic subunit. Third, the integrity of the three sites at positions 7, 23 and 99 was necessary for the cAMP-dependent increase in the Pf of oocytes expressing alpha-TIP, as well as for in vitro phosphorylation of alpha-TIP. These findings demonstrate that the alpha-TIP water channel can be modulated via phosphorylation of Ser7, Ser23 and Ser99.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7542585

  6. Activation of two new alpha(1,3)fucosyltransferase activities in Chinese hamster ovary cells by 5-azacytidine.

    PubMed Central

    Potvin, B; Stanley, P


    Several mammalian alpha(1,3)fucosyltransferases (alpha[1,3]Fuc-T) that synthesize carbohydrates containing alpha(1,3)fucosylated lactosamine units have been identified. Although Chinese hamster ovary (CHO) cells do not express alpha(1,3)Fuc-T activity, the rare mutants LEC11 and LEC12, isolated after mutagenesis or DNA transfection, each express an alpha(1,3)Fuc-T that may be distinguished by several criteria. Two new CHO mutants possessing alpha(1,3)Fuc-T activity (LEC29 and LEC30) have now been isolated after treatment of a CHO cell population with 5-azacytidine (5-AzaC), ethylnitrosourea (ENU), or 5-AzaC followed by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Like LEC12, both mutants possess an N-ethylmaleimide-resistant alpha(1,3)Fuc-T activity that can utilize a variety of acceptors and both express the Lewis X (Lex) determinant (Gal beta[1,4](Fuc alpha[1,3])GlcNAc beta 1)) but not the sialyl alpha(2,3)Lex determinant on cell-surface carbohydrates. However, LEC29 and LEC30 may be distinguished from LEC11 and LEC12, as well as from each other, on the basis of their unique patterns of lectin resistance and their abilities to bind the VIM-2 monoclonal antibody that recognizes carbohydrates terminating in NeuNAc alpha(2,3)Gal beta(1,4)GlcNAc beta(1,3)Gal beta(1,4)(Fuc alpha[1,3])GlcNAc beta and also by the different in vitro substrate specificities and kinetic properties of their respective alpha(1,3)Fuc-T activities. The combined data provide good evidence that the LEC29 and LEC30 alpha(1,3)Fuc-Ts are novel transferases encoded by distinct gene products. PMID:1724918

  7. Expression of human. alpha. sub 2 -macroglobulin cDNA in baby hamster kidney fibroblasts: Secretion of high levels of active. alpha. sub 2 -macroglobulin

    SciTech Connect

    Boel, E.; Mortensen, S.B. ); Kristensen, T.; Sottrup-Jensen, L. ); Petersen, C.M. )


    Human {alpha}{sub 2}-macroglobulin ({alpha}{sub 2}M) is a unique 720-kDa proteinase inhibitor with a broad specificity. Unlike most other proteinase inhibitors, it does not inhibit proteolytic activity by blocking the active site of the proteinase. During complex formation with a proteinase {alpha}{sub 2}M entraps the proteinase molecule in a reaction that involves large conformational changes in {alpha}{sub 2}M. The authors describe the molecular cloning of {alpha}{sub 2}M cDNA from the human hepatoblastoma cell line HepG2. The cDNA was subcloned under control of the adenovirus major late promoter in a mammalian expression vector and introduced into the baby hamster kidney (BHK) cell line. Transformed clones were isolated and tested for production of human {alpha}{sub 2}M with a specific enzyme-linked immunosorbent assay. Human recombinant {alpha}{sub 2}M (r{alpha}{sub 2}M), secreted and purified form isolated transfected BHK cell lines, was structurally and functionally compared to {alpha}{sub 2}M purified from human serum. The results show that r{alpha}{sub 2}M was secreted from the BHK cells as an active proteinase-binding tetramer with functional thiol esters. Cleavage reactions of r{alpha}{sub 2}M with methylamine and trypsin showed that the recombinant product, which was correctly processed at the N-terminus, exhibited molecular characteristics similar to those of the human serum derived reference.

  8. Variability of the Lyman alpha flux with solar activity

    SciTech Connect

    Lean, J.L.; Skumanich, A.


    A three-component model of the solar chromosphere, developed from ground based observations of the Ca II K chromospheric emission, is used to calculate the variability of the Lyman alpha flux between 1969 and 1980. The Lyman alpha flux at solar minimum is required in the model and is taken as 2.32 x 10/sup 11/ photons/cm/sup 2//s. This value occurred during 1975 as well as in 1976 near the commencement of solar cycle 21. The model predicts that the Lyman alpha flux increases to as much as 5 x 10/sup 11/ photons/cm/sup 2//s at the maximum of the solar cycle. The ratio of the average fluxes for December 1979 (cycle maximum) and July 1976 (cycle minimum) is 1.9. During solar maximum the 27-day solar rotation is shown to cause the Lyman alpha flux to vary by as much as 40% or as little as 5%. The model also shows that the Lyman alpha flux varies over intermediate time periods of 2 to 3 years, as well as over the 11-year sunspot cycle. We conclude that, unlike the sunspot number and the 10.7-cm radio flux, the Lyman alpha flux had a variability that was approximately the same during each of the past three cycles. Lyman alpha fluxes calculated by the model are consistent with measurements of the Lyman alpha flux made by 11 of a total of 14 rocket experiments conducted during the period 1969--1980. The model explains satisfactorily the absolute magnitude, long-term trends, and the cycle variability seen in the Lyman alpha irradiances by the OSO 5 satellite experiment. The 27-day variability observed by the AE-E satellite experiment is well reproduced. However, the magntidue of the AE-E 1 Lyman alpha irradiances are higher than the model calculations by between 40% and 80%. We suggest that the assumed calibration of the AE-E irradiances is in error.

  9. AMP-activated protein kinase kinase: detection with recombinant AMPK alpha1 subunit.


    Hamilton, Stephen R; O'Donnell, John B; Hammet, Andrew; Stapleton, David; Habinowski, Susan A; Means, Anthony R; Kemp, Bruce E; Witters, Lee A


    The AMP-activated protein kinase (AMPK) is a heterotrimeric serine/threonine protein kinase important for the responses to metabolic stress. It consists of a catalytic alpha subunit and two non-catalytic subunits, beta and gamma, and is regulated both by the allosteric action of AMP and by phosphorylation of the alpha and beta subunits catalyzed by AMPKK(s) and autophosphorylation. The Thr172 site on the alpha subunit has been previously characterized as an activating phosphorylation site. Using bacterially expressed AMPK alpha1 subunit proteins, we have explored the role of Thr172-directed AMPKKs in alpha subunit regulation. Recombinant alpha1 subunit proteins, representing the N-terminus, have been expressed as maltose binding protein (MBP) 6x His fusion proteins and purified to homogeneity by Ni(2+) chromatography. Both wild-type alpha1(1-312) and alpha1(1-312)T172D are inactive when expressed in bacteria, but the former can be fully phosphorylated (1 mol/mol) on Thr172 and activated by a surrogate AMPKK, CaMKKbeta. The corresponding AMPKalpha1(1-392), an alpha construct containing its autoinhibitory sequence, can be similarly phosphorylated, but it remains inactive. In an insulinoma cell line, either low glucose or 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) treatment leads to activation and T172 phosphorylation of endogenous AMPK. Under the same conditions of cell incubation, we have identified an AMPKK activity that both phosphorylates and activates the recombinant alpha1(1-312), but this Thr172-directed AMPKK activity is unaltered by low glucose or AICAR, indicating that it is constitutively active. PMID:12051742

  10. Dynamic peripheral visual performance relates to alpha activity in soccer players.


    Nan, Wenya; Migotina, Daria; Wan, Feng; Lou, Chin Ian; Rodrigues, João; Semedo, João; Vai, Mang I; Pereira, Jose Gomes; Melicio, Fernando; Da Rosa, Agostinho C


    Many studies have demonstrated the relationship between the alpha activity and the central visual ability, in which the visual ability is usually assessed through static stimuli. Besides static circumstance, however in the real environment there are often dynamic changes and the peripheral visual ability in a dynamic environment (i.e., dynamic peripheral visual ability) is important for all people. So far, no work has reported whether there is a relationship between the dynamic peripheral visual ability and the alpha activity. Thus, the objective of this study was to investigate their relationship. Sixty-two soccer players performed a newly designed peripheral vision task in which the visual stimuli were dynamic, while their EEG signals were recorded from Cz, O1, and O2 locations. The relationship between the dynamic peripheral visual performance and the alpha activity was examined by the percentage-bend correlation test. The results indicated no significant correlation between the dynamic peripheral visual performance and the alpha amplitudes in the eyes-open and eyes-closed resting condition. However, it was not the case for the alpha activity during the peripheral vision task: the dynamic peripheral visual performance showed significant positive inter-individual correlations with the amplitudes in the alpha band (8-12 Hz) and the individual alpha band (IAB) during the peripheral vision task. A potential application of this finding is to improve the dynamic peripheral visual performance by up-regulating alpha activity using neuromodulation techniques. PMID:25426058

  11. Tumor cell alpha-N-acetylgalactosaminidase activity and its involvement in GcMAF-related macrophage activation.


    Mohamad, Saharuddin B; Nagasawa, Hideko; Uto, Yoshihiro; Hori, Hitoshi


    Alpha-N-acetyl galactosaminidase (alpha-NaGalase) has been reported to accumulate in serum of cancer patients and be responsible for deglycosylation of Gc protein, which is a precursor of GcMAF-mediated macrophage activation cascade, finally leading to immunosuppression in advanced cancer patients. We studied the biochemical characterization of alpha-NaGalase from several human tumor cell lines. We also examined its effect on the potency of GcMAF to activate mouse peritoneal macrophage to produce superoxide in GcMAF-mediated macrophage activation cascade. The specific activity of alpha-NaGalases from human colon tumor cell line HCT116, human hepatoma cell line HepG2, and normal human liver cells (Chang liver cell line) were evaluated using two types of substrates; GalNAc-alpha-PNP (exo-type substrate) and Gal-beta-GalNAc-alpha-PNP (endo-type substrate). Tumor-derived alpha-NaGalase having higher activity than normal alpha-NaGalase, had higher substrate specificity to the exo-type substrate than to the endo-type substrate, and still maintained its activity at pH 7. GcMAF enhance superoxide production in mouse macrophage, and pre-treatment of GcMAF with tumor cell lysate reduce the activity. We conclude that tumor-derived alpha-NaGalase is different in biochemical characterization compared to normal alpha-NaGalase from normal Chang liver cells. In addition, tumor cell-derived alpha-NaGalase decreases the potency of GcMAF on macrophage activation. PMID:12062184

  12. Biologically active monoiodinated alpha-MSH derivatives for receptor binding studies using human melanoma cells

    SciTech Connect

    Eberle, A.N.; Verin, V.J.; Solca, F.; Siegrist, W.; Kueenlin, C.B.; Bagutti, C.; Stutz, S.; Girard, J. , University Hospital, Basel )


    Three different monoiodinated radioligands of alpha-MSH (alpha-melanocyte-stimulating hormone) were compared in a binding assay with human D10 melanoma cells: (Tyr(125I)2)-alpha-MSH, (Tyr(125I)2,NIe4)-alpha-MSH, and (Tyr(125I)2,NIe4,D-Phe7)-alpha-MSH. They were prepared either by the classical chloramine T method or by the Enzymobead method. A simple and rapid purification scheme was developed consisting of a primary separation on reversed-phase C18 silica cartridges immediately after the iodination, followed by HPLC purification before each binding experiment. Biological testing of the three radioligands showed that they all retained high melanotropic activity in the B16 melanin assay and the Anolis melanophore assay. However, in human D10 melanoma cells, (Tyr(125I)2,NIe4)-alpha-MSH led to a high degree of non-specific binding to the cells which could not be displaced by excess alpha-MSH and only partially by (NIe4)-alpha-MSH. The (Tyr(125I)2,NIe4,D-Phe7)-alpha-MSH tracer gave similar results but with a much lower proportion of non-specific binding. On the other hand, (Tyr(125I)2)-alpha-MSH proved to be an excellent radioligand whose non-specific binding to the D10 cells was not higher than 20% of the total binding.

  13. Alpha-adrenoceptor agonistic activity of oxymetazoline and xylometazoline.


    Haenisch, Britta; Walstab, Jutta; Herberhold, Stephan; Bootz, Friedrich; Tschaikin, Marion; Ramseger, René; Bönisch, Heinz


    Oxymetazoline and xylometazoline are both used as nasal mucosa decongesting α-adrenoceptor agonists during a common cold. However, it is largely unknown which of the six α-adrenoceptor subtypes are actually present in human nasal mucosa, which are activated by the two alpha-adrenoceptor agonists and to what extent. Therefore, mRNA expression in human nasal mucosa of the six α-adrenoceptor subtypes was studied. Furthermore, the affinity and potency of the imidazolines oxymetazoline and xylometazoline at these α-adrenoceptor subtypes were examined in transfected HEK293 cells. The rank order of mRNA levels of α-adrenoceptor subtypes in human nasal mucosa was: α(2A) > α(1A) ≥ α(2B) > α(1D) ≥ α(2C) > α(1B) . Oxymetazoline and xylometazoline exhibited in radioligand competition studies higher affinities than the catecholamines adrenaline and noradrenaline at most α-adrenoceptor subtypes. Compared to xylometazoline, oxymetazoline exhibited a significantly higher affinity at α(1A) - but a lower affinity at α(2B) -adrenoceptors. In functional studies in which adrenoceptor-mediated Ca(2+) signals were measured, both, oxymetazoline and xylometazoline behaved at α(2B) -adrenoceptors as full agonists but oxymetazoline was significantly more potent than xylometazoline. Furthermore, oxymetazoline was also a partial agonist at α(1A) -adrenoceptors; however, its potency was relatively low and it was much lower than its affinity. The higher potency at α(2B) -adrenoceptors, i.e. at receptors highly expressed at the mRNA level in human nasal mucosa, could eventually explain why in nasal decongestants oxymetazoline can be used in lower concentrations than xylometazoline. PMID:20030735

  14. Frontal Alpha EEG Asymmetry Before and After Behavioral Activation Treatment for Depression

    PubMed Central

    Gollan, Jackie K.; Hoxha, Denada; Chihade, Dietta; Pflieger, Mark E.; Rosebrock, Laina; Cacioppo, John


    Background Mid-frontal and mid-lateral (F3/F4 and F7/F8) EEG asymmetry has been associated with motivation and affect. We examined alpha EEG asymmetry in depressed and healthy participants before and after Behavioral Activation treatment for depression; examined the association between alpha EEG asymmetry and motivational systems and affect; and evaluated the utility of alpha EEG asymmetry in predicting remission. Methods Depressed (n = 37) and healthy participants (n = 35) were assessed before and after treatment using a clinical interview, a task to measure baseline EEG, and questionnaires of behavioral activation and inhibition, avoidance, and affect. Results Alpha EEG asymmetry was significantly higher in depressed than healthy participants at pre-treatment, positively correlated with negative affect and behavioral inhibition, and inversely correlated with lower behavioral activation sensitivity. Conclusions Heightened alpha EEG asymmetry in depressed participants was significantly associated with increased behavioral inhibition and negative emotion and was independent of clinical remission. PMID:24674708

  15. Exposure to airborne metals and particulate matter and risk for youth adjudicated for criminal activity

    SciTech Connect

    Haynes, Erin N.; Chen, Aimin; Ryan, Patrick; Succop, Paul; Wright, John; Dietrich, Kim N.


    Antisocial behavior is a product of multiple interacting sociohereditary variables, yet there is increasing evidence that metal exposure, particularly, manganese and lead, play a role in its epigenesis. Other metals, such as arsenic, cadmium, chromium, and mercury, and exposure to traffic-related air pollution, such as fine particulate matter ({<=}2.5 {mu}m) have been associated with neurological deficits, yet largely unexplored with respect to their relationship with delinquent behavior. The purpose of this study is to evaluate the ecological relationship between county-wide reported airborne emissions of air metals, particulate matter, and youth adjudicated for criminal activity. Metal exposure data were collected from the Environmental Protection Agency AirData. Population statistics were obtained from the United States Census 2000 and adjudication data was obtained from the Courts of Common Pleases from each Ohio County. Simple correlations were calculated with the percentage of adjudications, all covariates, and estimated metal air emissions. Separate negative binomial regression models for each pollutant were used to provide an estimated risk ratio of pollutant emissions on the risk of adjudication for all Ohio counties adjusting for urban-rural residence, percentage of African Americans, median family income, percentage of family below poverty, percentage of high school graduation in 25 years and older populations, and population density. Metal emissions and PM in 1999 were all correlated with adjudication rate (2003-2005 average). Metal emissions were associated with slightly higher risk of adjudication, with about 3-4% increased risk per natural log unit of metal emission except chromium. The associations achieved statistical significance for manganese and mercury. The particulate matter {<=}2.5 and {<=}10 {mu}m emissions had a higher risk estimate, with 12% and 19% increase per natural log unit emission, respectively, and also achieved statistical

  16. Mimicking phosphorylation of alphaB-crystallin affects its chaperone activity.


    Ecroyd, Heath; Meehan, Sarah; Horwitz, Joseph; Aquilina, J Andrew; Benesch, Justin L P; Robinson, Carol V; Macphee, Cait E; Carver, John A


    AlphaB-crystallin is a member of the sHsp (small heat-shock protein) family that prevents misfolded target proteins from aggregating and precipitating. Phosphorylation at three serine residues (Ser19, Ser45 and Ser59) is a major post-translational modification that occurs to alphaB-crystallin. In the present study, we produced recombinant proteins designed to mimic phosphorylation of alphaB-crystallin by incorporating a negative charge at these sites. We employed these mimics to undertake a mechanistic and structural investigation of the effect of phosphorylation on the chaperone activity of alphaB-crystallin to protect against two types of protein misfolding, i.e. amorphous aggregation and amyloid fibril assembly. We show that mimicking phosphorylation of alphaB-crystallin results in more efficient chaperone activity against both heat-induced and reduction-induced amorphous aggregation of target proteins. Mimick-ing phosphorylation increased the chaperone activity of alphaB-crystallin against one amyloid-forming target protein (kappa-casein), but decreased it against another (ccbeta-Trp peptide). We observed that both target protein identity and solution (buffer) conditions are critical factors in determining the relative chaperone ability of wild-type and phosphorylated alphaB-crystallins. The present study provides evidence for the regulation of the chaperone activity of alphaB-crystallin by phosphorylation and indicates that this may play an important role in alleviating the pathogenic effects associated with protein conformational diseases. PMID:16928191

  17. Prostaglandin F/sub 2. cap alpha. activates phosphoinositide hydrolysis in rat aorta

    SciTech Connect

    Not Available


    The authors have previously demonstrated that norepinephrine (NE) and serotonin (5HT) activate a phosphoinositide-(PI) specific phospholipase C in rat aorta by interaction with ..cap alpha../sub 1/-adrenergic receptors and 5HT/sub 2/ receptor, respectively. They have subsequently noted that angiotensin II and vasopressin as well activate PI hydrolysis in the tissue. The most active agent they have thus far investigated is prostaglandin F/sub 2..cap alpha../ (PGF/sub 2..cap alpha../). Rat aortic rings were pre-labelled with (/sup 3/H)-inositol and then, in the presence of 10 mM LiCl, exposed to various doses of PGF/sub 2..cap alpha../. (/sup 3/H)-inositol monophosphate was the quantified by anion-exchange chromatography. After a 60 min incubation, PGF/sub 2..cap alpha../ caused a 10-15 fold increase over basal at maximal concentrations (0.1-1.0 mM). An EC/sub 50/ for PI hydrolysis was between 0.1-1.0 PGF/sub 2..cap alpha../ caused maximal aortic contraction at 10 PGF/sub 2..cap alpha../-induced PI hydrolysis, was inhibited by phorbol esters. These results suggest that PGF/sub 2..cap alpha../, similar to 5HT, NE, vasopressin and angiotensin II, causes vasoconstriction by activation of PI hydrolysis.

  18. TRIM5{alpha} association with cytoplasmic bodies is not required for antiretroviral activity

    SciTech Connect

    Song, Byeongwoon; Diaz-Griffero, Felipe; Park, Do Hyun; Rogers, Thomas; Stremlau, Matthew; Sodroski, Joseph . E-mail:


    The tripartite motif (TRIM) protein, TRIM5{alpha}, restricts infection by particular retroviruses. Many TRIM proteins form cytoplasmic bodies of unknown function. We investigated the relationship between cytoplasmic body formation and the structure and antiretroviral activity of TRIM5{alpha}. In addition to diffuse cytoplasmic staining, the TRIM5{alpha} proteins from several primate species were located in cytoplasmic bodies of different sizes; by contrast, TRIM5{alpha} from spider monkeys did not form cytoplasmic bodies. Despite these differences, all of the TRIM5{alpha} proteins exhibited the ability to restrict infection by particular retroviruses. Treatment of cells with geldanamycin, an Hsp90 inhibitor, resulted in disappearance or reduction of the TRIM5{alpha}-associated cytoplasmic bodies, yet exerted little effect on the restriction of retroviral infection. Studies of green fluorescent protein-TRIM5{alpha} fusion proteins indicated that no TRIM5{alpha} domain is specifically required for association with cytoplasmic bodies. Apparently, the formation of cytoplasmic bodies is not required for the antiretroviral activity of TRIM5{alpha}.

  19. Alpha contamination assessment for D&D activities: Technology overview

    SciTech Connect

    Conaway, J.G.; Rawool-Sullivan, M.W.; MacArthur, D.W.


    Instruments based on the principle of Long-Range Alpha Detection (LRAD) detect the ions created in ambient air by Ionizing radiation, particularly alpha radiation, interacting with air molecules. Using either an electrostatic field or forced convection, these ions can be transported to a detection grid where the ions produce a small current that is measured with a sensitive electrometer. LRAD-based instruments can give separate, simultaneous measurements of alpha-emitting solids and inert radioactive gases such as radon. LRAD-based instruments assess surface contamination on an entire object or large surface area in a single, rapid measurement, including relatively inaccessible areas such as interior surfaces of pipes and process equipment. The LRAD concept is well proven and has been developed into a range of different radiation detection devices. This paper presents an overview of the technology, while several associated papers explore specific applications in greater detail.

  20. Airborne Active and Passive L-Band Observations in Soil Moisture Active Passive Validation Experiment 2012 (SMAPVEX12)

    NASA Astrophysics Data System (ADS)

    Colliander, A.; Yueh, S. H.; Chazanoff, S.; Jackson, T. J.; McNairn, H.; Bullock, P.; Wiseman, G.; Berg, A. A.; Magagi, R.; Njoku, E. G.


    NASA's (National Aeronautics and Space Administration) Soil Moisture Active Passive (SMAP) Mission is scheduled for launch in October 2014. The objective of the mission is global mapping of soil moisture and freeze/thaw state. Merging of active and passive L-band observations of the mission will enable unprecedented combination of accuracy, resolution, coverage and revisit-time for soil moisture and freeze/thaw state retrieval. For pre-launch algorithm development and validation the SMAP project and NASA coordinated a field campaign named as SMAPVEX12 (Soil Moisture Active Passive Validation Experiment 2012) together with Agriculture and Agri-Food Canada in the vicinity of Winnipeg, Canada in June-July, 2012. The main objective of SMAPVEX12 was acquisition of data record that features long-time series with varying soil moisture and vegetation conditions (for testing the application of time-series approach) over aerial domain of multiple parallel lines (for spatial disaggregation studies). The coincident active and passive L-band data were acquired using the Passive Active L-band System (PALS), which is an airborne radiometer and radar developed for testing L-band retrieval algorithms. For SMAPVEX12 PALS was installed on a Twin Otter aircraft. The flight plan included flights at two altitudes. The higher altitude was used to map the whole experiment domain and the lower altitude was used to obtain measurements over a specific set of field sites. The spatial resolution (and swath) of the radar and radiometer from low altitude was about 600 m and from high altitude about 1500 m. The PALS acquisitions were complemented with high resolution (~10 m) L-band SAR measurements carried out by UAVSAR instrument on-board G-III aircraft. The campaign ran from June 7 until July 19. The PALS instrument conducted 17 brightness temperature and backscatter measurement flights and the UAVSAR conducted 14 backscatter measurement flights. The airborne data acquisition was supported by

  1. Cytosolic PLA2(alpha) activation in Purkinje neurons and its role in AMPA-receptor trafficking.


    Mashimo, Masato; Hirabayashi, Tetsuya; Murayama, Toshihiko; Shimizu, Takao


    Cytosolic phospholipase A(2)alpha (cPLA(2)alpha) selectively releases arachidonic acid from membrane phospholipids and has been proposed to be involved in the induction of long-term depression (LTD), a form of synaptic plasticity in the cerebellum. This enzyme requires two events for its full activation: Ca(2+)-dependent translocation from the cytosol to organelle membranes in order to access phospholipids as substrates, and phosphorylation by several kinases. However, the subcellular distribution and activation of cPLA(2)alpha in Purkinje cells and the role of arachidonic acid in cerebellar LTD have not been fully elucidated. In cultured Purkinje cells, stimulation of AMPA receptors, but not metabotropic glutamate receptors, triggered translocation of cPLA(2)alpha to the somatic and dendritic Golgi compartments. This translocation required Ca(2+) influx through P-type Ca(2+) channels. AMPA plus PMA, a chemical method for inducing LTD, released arachidonic acid via phosphorylation of cPLA(2)alpha. AMPA plus PMA induced a decrease in surface GluR2 for more than 2 hours. Interestingly, this reduction was occluded by a cPLA(2)alpha-specific inhibitor. Furthermore, PMA plus arachidonic acid caused the prolonged internalization of GluR2 without activating AMPA receptors. These results suggest that cPLA(2)alpha regulates the persistent decrease in the expression of AMPA receptors, underscoring the role of cPLA(2)alpha in cerebellar LTD. PMID:18713832

  2. EEG Alpha and Beta Activity in Normal and Deaf Subjects.

    ERIC Educational Resources Information Center

    Waldron, Manjula; And Others

    Electroencephalogram and task performance data were collected from three groups of young adult males: profoundly deaf Ss who signed from an early age, profoundly deaf Ss who only used oral (speech and speedreading) methods of communication, and normal hearing Ss. Alpha and Beta brain wave patterns over the Wernicke's area were compared across…

  3. Effect of alpha-actinin on actin structure. Actin ATPase activity.


    Singh, I; Goll, D E; Robson, R M


    Alpha-Actinin increases the ATPase activity of actin by up to 84%, depending un pH, divalent cations present and the added Mg2+: ATP ratio. Dithiothreitol decreases actin ATPase activity approx. 20% but does not reduce the ability of alpha-actinin to increase actin ATP activity. Increasing amounts of added alpha-actinin up to 1 mos alpha-actinin to 49 mol actin cause in increasing increment in actin ATPase activity, but adding alpha-actinin beyond 1 mol alpha-actinin to 49 mol actin elicits only small additional increments in activity. Actin ATPase activity ranges from approx 100 nmol Pi/mg actin per h (4.3 mol Pi/mol actin per h) at high levels (10 mM) of ATP in the presence of lower amounts (1 mM) of added mg2+ to approx. 12.5 nmol Pi/mg actin per h (0.52 mol Pi/mol actin per h) at high pH (8.5) or at low levels (0.5-1.0 mM) of ATP in the presence of higher amounts (10 mM) of added Mg2+ ATp uncomplexed with Mg2+ inhibits the ability of alpha-actinin to increase F-actin ATPase activity. Activities with different divalent cations showed that the actin ATPase in these studies, which was 1/100 as great as Mg2+-modified actomyosin ATPase activity, was not due to trace amounts of myosin contaminating the actin preparations. The results are consistent with the concept that alpha-actinin can alter the structure of actin monomers. PMID:6456018

  4. Alternate particle removal technologies for the Airborne Activity Confinement System at the Savannah River Site

    SciTech Connect

    Brockmann, J.E.; Adkins, C.L.J.; Gelbard, F. )


    This report presents a review of the filtration technologies available for the removal of particulate material from a gas stream. It was undertaken to identify alternate filtration technologies that may be employed in the Airborne Activity Confinement System (AACS) at the Savannah River Plant. This report is organized into six sections: (1) a discussion of the aerosol source term and its definition, (2) a short discussion of particle and gaseous contaminant removal mechanisms, (3) a brief overview of particle removal technologies, (4) a discussion of the existing AACS and its potential shortcomings, (5) an enumeration of issues to be addressed in upgrading the AACS, and, (6) a detailed discussion of the identified technologies. The purpose of this report is to identity available options to the existing particle removal system. This system is in continuous operation during routine operation of the reactor. As will be seen, there are a number of options and the selection of any technology or combination of technologies will depend on the design aerosol source term (yet to be appropriately defined) as well as the flow requirements and configuration. This report does not select a specific technology. It focuses on particulate removal and qualitatively on the removal of radio-iodine and mist elimination. Candidate technologies have been selected from industrial and nuclear gas cleaning applications.

  5. Characterization of airborne particles generated from metal active gas welding process.


    Guerreiro, C; Gomes, J F; Carvalho, P; Santos, T J G; Miranda, R M; Albuquerque, P


    This study is focused on the characterization of particles emitted in the metal active gas welding of carbon steel using mixture of Ar + CO2, and intends to analyze which are the main process parameters that influence the emission itself. It was found that the amount of emitted particles (measured by particle number and alveolar deposited surface area) are clearly dependent on the distance to the welding front and also on the main welding parameters, namely the current intensity and heat input in the welding process. The emission of airborne fine particles seems to increase with the current intensity as fume-formation rate does. When comparing the tested gas mixtures, higher emissions are observed for more oxidant mixtures, that is, mixtures with higher CO2 content, which result in higher arc stability. These mixtures originate higher concentrations of fine particles (as measured by number of particles by cm(3) of air) and higher values of alveolar deposited surface area of particles, thus resulting in a more severe worker's exposure. PMID:24730680

  6. A novel type of thermostable alpha-D-glucosidase from Thermoanaerobacter thermohydrosulfuricus exhibiting maltodextrinohydrolase activity.

    PubMed Central

    Wimmer, B; Lottspeich, F; Ritter, J; Bronnenmeier, K


    An alpha-glucosidase with the ability to attack polymeric substrates was purified to homogeneity from culture supernatants of Thermoanaerobacter thermohydrosulfuricus DSM 567. The enzyme is apparently a glycoprotein with a molecular mass of 160 kDa. Maximal activity is observed between pH5 and 7 at 75 degrees C. The alpha-glucosidase is active towards p-nitrophenyl-alpha-D-glucoside, maltose, malto-oligosaccharides, starch and pullulan. Highest activity is displayed towards the disaccharide maltose. In addition to glucose, maltohexaose and maltoheptaose can be detected as the initial products of starch hydrolysis. After short incubations of pullulan, glucose is found as the only product. At high substrate concentrations, maltose and malto-oligosaccharide, but not glucose, are used as acceptors for glucosyl-transfer. These findings indicate that the T. thermohydrosulfuricus enzyme represents a novel type of alpha-glucosidase exhibiting maltase, glucohydrolase and 'maltodextrinohydrolase' activity. PMID:9371718

  7. AMPK activation regulates apoptosis, adipogenesis, and lipolysis by eIF2{alpha} in adipocytes

    SciTech Connect

    Dagon, Yossi; Avraham, Yosefa; Berry, Elliot M. . E-mail:


    AMP-activated protein kinase (AMPK) is a metabolic master switch regulating glucose and lipid metabolism. Recently, AMPK has been implicated in the control of adipose tissue content. Yet, the nature of this action is controversial. We examined the effect on F442a adipocytes of the AMPK activator-AICAR. Activation of AMPK induced dose-dependent apoptotic cell death, inhibition of lipolysis, and downregulatation key adipogenic genes, such as peroxisome proliferator-activated receptor (PPAR{gamma}) and CCAAT/enhancer-binding protein alpha (C/EBP{alpha}). We have identified the {alpha}-subunit of the eukaryotic initiation factor-2 (eIF2{alpha}) as a target gene which is phosphorylated following AICAR treatment. Such phosphorylation is one of the best-characterized mechanisms for downregulating protein synthesis. 2-Aminopurine (2-AP), an inhibitor of eIF2{alpha} kinases, could overcome the apoptotic effect of AICAR, abolishing the reduction of PPAR{gamma} and C/EBP{alpha} and the lipolytic properties of AMPK. Thus, AMPK may diminish adiposity via reduction of fat cell number through eIF2{alpha}-dependent translation shutdown.

  8. alpha-Glycosidase inhibitory activity of hexagalloylglucose from the galls of Quercus infectoria.


    Hwang, J K; Kong, T W; Baek, N I; Pyun, Y R


    Hexagalloylglucose (3-O-digalloyl-1,2,4,6-tetra-O-galloyl-beta-D- glucose), which was isolated from the methanol extract of the galls of Quercus infectoria, significantly inhibited alpha-glycosidases such as sucrase, maltase and isomaltase. Its inhibitory activity was comparable to acarbose being used as a hypoglycemic agent, while the inhibitory activity on alpha-amylase was approximately 10 times lower than that of acarbose. The results indicate that, when compared to acarbose, hexagalloylglucose might reduce the side effects by reducing inhibition of alpha-amylase. PMID:10821056

  9. Influence of source composition and particle energy on the determination of gross alpha activity.


    Timón, A Fernández; Vargas, M Jurado; Sánchez, A B Ruano; Pérez, J de la Torre; Sánchez, A Martín


    The influence of different source compositions and α-particle energies on the detection efficiency of a gas-flow proportional counter was examined using experimental measurements and Monte Carlo simulations. Efficiency variation with alpha-particle energy was very marked, being less significant with the substrate composition. These results show that the determination of gross alpha activity in an unknown sample must be carried out very carefully in order to give a correct estimation of its activity. PMID:24184741

  10. Transcriptional co-activator PGC-1 alpha drives the formation of slow-twitch muscle fibres.


    Lin, Jiandie; Wu, Hai; Tarr, Paul T; Zhang, Chen-Yu; Wu, Zhidan; Boss, Olivier; Michael, Laura F; Puigserver, Pere; Isotani, Eiji; Olson, Eric N; Lowell, Bradford B; Bassel-Duby, Rhonda; Spiegelman, Bruce M


    The biochemical basis for the regulation of fibre-type determination in skeletal muscle is not well understood. In addition to the expression of particular myofibrillar proteins, type I (slow-twitch) fibres are much higher in mitochondrial content and are more dependent on oxidative metabolism than type II (fast-twitch) fibres. We have previously identified a transcriptional co-activator, peroxisome-proliferator-activated receptor-gamma co-activator-1 (PGC-1 alpha), which is expressed in several tissues including brown fat and skeletal muscle, and that activates mitochondrial biogenesis and oxidative metabolism. We show here that PGC-1 alpha is expressed preferentially in muscle enriched in type I fibres. When PGC-1 alpha is expressed at physiological levels in transgenic mice driven by a muscle creatine kinase (MCK) promoter, a fibre type conversion is observed: muscles normally rich in type II fibres are redder and activate genes of mitochondrial oxidative metabolism. Notably, putative type II muscles from PGC-1 alpha transgenic mice also express proteins characteristic of type I fibres, such as troponin I (slow) and myoglobin, and show a much greater resistance to electrically stimulated fatigue. Using fibre-type-specific promoters, we show in cultured muscle cells that PGC-1 alpha activates transcription in cooperation with Mef2 proteins and serves as a target for calcineurin signalling, which has been implicated in slow fibre gene expression. These data indicate that PGC-1 alpha is a principal factor regulating muscle fibre type determination. PMID:12181572

  11. Cooperative interaction of hypoxia-inducible factor-2alpha (HIF-2alpha ) and Ets-1 in the transcriptional activation of vascular endothelial growth factor receptor-2 (Flk-1).


    Elvert, Gerd; Kappel, Andreas; Heidenreich, Regina; Englmeier, Ursula; Lanz, Stephan; Acker, Till; Rauter, Manuel; Plate, Karl; Sieweke, Michael; Breier, Georg; Flamme, Ingo


    Interactions between Ets family members and a variety of other transcription factors serve important functions during development and differentiation processes, e.g. in the hematopoietic system. Here we show that the endothelial basic helix-loop-helix PAS domain transcription factor, hypoxia-inducible factor-2alpha (HIF-2alpha) (but not its close relative HIF-1alpha), cooperates with Ets-1 in activating transcription of the vascular endothelial growth factor receptor-2 (VEGF-2) gene (Flk-1). The receptor tyrosine kinase Flk-1 is indispensable for angiogenesis, and its expression is closely regulated during development. Consistent with the hypothesis that HIF-2alpha controls the expression of Flk-1 in vivo, we show here that HIF-2alpha and Flk-1 are co-regulated in postnatal mouse brain capillaries. A tandem HIF-2alpha/Ets binding site was identified within the Flk-1 promoter that acted as a strong enhancer element. Based on the analysis of transgenic mouse embryos, these motifs are essential for endothelial cell-specific reporter gene expression. A single HIF-2alpha/Ets element conferred strong cooperative induction by HIF-2alpha and Ets-1 when fused to a heterologous promoter and was most active in endothelial cells. The physical interaction of HIF-2alpha with Ets-1 was demonstrated and localized to the HIF-2alpha carboxyl terminus and the autoinhibitory exon VII domain of Ets-1, respectively. The deletion of the DNA binding and carboxyl-terminal transactivation domains of HIF-2alpha, respectively, created dominant negative mutants that suppressed transactivation by the wild type protein and failed to synergize with Ets-1. These results suggest that the interaction between HIF-2alpha and endothelial Ets factors is required for the full transcriptional activation of Flk-1 in endothelial cells and may therefore represent a future target for the manipulation of angiogenesis. PMID:12464608

  12. Short term integrative meditation improves resting alpha activity and stroop performance.


    Fan, Yaxin; Tang, Yi-Yuan; Tang, Rongxiang; Posner, Michael I


    Our previous research showed that short term meditation training reduces the time to resolve conflict in the flanker task. Studies also show that resting alpha increases with long term meditation practice. The aim of this study is to determine whether short term meditation training both increases resting alpha activity and reduces the time to resolve conflict in the Stroop task and whether these two effects are related. Forty-three Chinese undergraduates were randomly assigned an experiment group given 5 days meditation training using integrative body-mind training (IBMT) and a relaxation training control. After training, only the IBMT group showed decreased conflict reaction time (RT), and increased resting mean alpha power. Moreover, the higher the enhancement of resting alpha power, the stronger the improvement of conflict RT. The results indicate that short term meditation diffusely enhances alpha and improves the ability to deal with conflict and moreover these two effects are positively related. PMID:25253652

  13. The peptide LSARLAF causes platelet secretion and aggregation by directly activating the integrin alphaIIbbeta3.

    PubMed Central

    Derrick, J M; Taylor, D B; Loudon, R G; Gartner, T K


    A novel peptide (designed to bind to alphaIIbbeta3) caused platelet aggregation and aggregation-independent secretion of the contents of alpha-granules in an alphaIIbbeta3-dependent fashion. The agonist peptide induced secretion in the presence of prostaglandin E1. In cell-free assays, alphaIIbbeta3 bound specifically to immobilized agonist peptide and the peptide enhanced the binding of fibrinogen to immobilized alphaIIbbeta3. The agonist peptide apparently activates alphaIIbbeta3 by directly inducing a conformational change in the receptor. This change activates the platelets and causes secretion in a manner independent of fibrinogen binding. PMID:9230107

  14. The periplasmic alpha-carbonic anhydrase activity of Helicobacter pylori is essential for acid acclimation.


    Marcus, Elizabeth A; Moshfegh, Amiel P; Sachs, George; Scott, David R


    The role of the periplasmic alpha-carbonic anhydrase (alpha-CA) (HP1186) in acid acclimation of Helicobacter pylori was investigated. Urease and urea influx through UreI have been shown to be essential for gastric colonization and for acid survival in vitro. Intrabacterial urease generation of NH3 has a major role in regulation of periplasmic pH and inner membrane potential under acidic conditions, allowing adequate bioenergetics for survival and growth. Since alpha-CA catalyzes the conversion of CO2 to HCO3-, the role of CO2 in periplasmic buffering was studied using an alpha-CA deletion mutant and the CA inhibitor acetazolamide. Western analysis confirmed that alpha-CA was bound to the inner membrane. Immunoblots and PCR confirmed the absence of the enzyme and the gene in the alpha-CA knockout. In the mutant or in the presence of acetazolamide, there was an approximately 3 log10 decrease in acid survival. In acid, absence of alpha-CA activity decreased membrane integrity, as observed using membrane-permeant and -impermeant fluorescent DNA dyes. The increase in membrane potential and cytoplasmic buffering following urea addition to wild-type organisms in acid was absent in the alpha-CA knockout mutant and in the presence of acetazolamide, although UreI and urease remained fully functional. At low pH, the elevation of cytoplasmic and periplasmic pH with urea was abolished in the absence of alpha-CA activity. Hence, buffering of the periplasm to a pH consistent with viability depends not only on NH3 efflux from the cytoplasm but also on the conversion of CO2, produced by urease, to HCO3- by the periplasmic alpha-CA. PMID:15629943

  15. Retinoic acid activates human inducible nitric oxide synthase gene through binding of RAR{alpha}/RXR{alpha} heterodimer to a novel retinoic acid response element in the promoter

    SciTech Connect

    Zou Fang; Liu Yan; Liu Li; Wu Kailang; Wei Wei; Zhu Ying . E-mail:; Wu Jianguo . E-mail:


    Human inducible nitric oxide synthase (hiNOS) catalyzes nitric oxide (NO) which has a significant effect on tumor suppression and cancer therapy. Here we revealed the detailed molecular mechanism involved in the regulation of hiNOS expression induced by retinoic acid (RA). We showed that RAR{alpha}/RXR{alpha} heterodimer was important in hiNOS promoter activation, hiNOS protein expression, and NO production. Serial deletion and site-directed mutation analysis revealed two half-sites of retinoic acid response element (RARE) spaced by 5 bp located at -172 to -156 in the hiNOS promoter. EMSA and ChIP assays demonstrated that RAR{alpha}/RXR{alpha} directly bound to this RARE of hiNOS promoter. Our results suggested the identification of a novel RARE in the hiNOS promoter and the roles of the nuclear receptors (RAR{alpha}/RXR{alpha}) in the induction of hiNOS by RA.

  16. Ginsenoside Rf, a component of ginseng, regulates lipoprotein metabolism through peroxisome proliferator-activated receptor {alpha}

    SciTech Connect

    Lee, Hyunghee; Gonzalez, Frank J.; Yoon, Michung . E-mail:


    We investigated whether ginseng regulates lipoprotein metabolism by altering peroxisome proliferator-activated receptor {alpha} (PPAR{alpha})-mediated pathways, using a PPAR{alpha}-null mouse model. Administration of ginseng extract, ginsenosides, and ginsenoside Rf (Rf) to wild-type mice not only significantly increased basal levels of hepatic apolipoprotein (apo) A-I and C-III mRNA compared with wild-type controls, but also substantially reversed the reductions in mRNA levels of apo A-I and C-III expected following treatment with the potent PPAR{alpha} ligand Wy14,643. In contrast, no effect was detected in the PPAR{alpha}-null mice. Testing of eight main ginsenosides on PPAR{alpha} reporter gene expression indicated that Rf was responsible for the effects of ginseng on lipoprotein metabolism. Furthermore, the inhibition of PPAR{alpha}-dependent transactivation by Rf seems to occur at the level of DNA binding. These results demonstrate that ginseng component Rf regulates apo A-I and C-III mRNA and the actions of Rf on lipoprotein metabolism are mediated via interactions with PPAR{alpha}.

  17. Glucocorticoid receptor (GR) {beta} has intrinsic, GR{alpha}-independent transcriptional activity

    SciTech Connect

    Kino, Tomoshige; Manoli, Irini; Kelkar, Sujata; Wang, Yonghong; Su, Yan A.; Chrousos, George P.


    The human glucocorticoid receptor (GR) gene produces C-terminal GR{beta} and GR{alpha} isoforms through alternative use of specific exons 9{beta} and {alpha}, respectively. We explored the transcriptional activity of GR{beta} on endogenous genes by developing HeLa cells stably expressing EGFP-GR{beta} or EGFP. Microarray analyses revealed that GR{beta} had intrinsic gene-specific transcriptional activity, regulating mRNA expression of a large number of genes negatively or positively. Majority of GR{beta}-responsive genes was distinct from those modulated by GR{alpha}, while GR{beta} and GR{alpha} mutually modulated each other's transcriptional activity in a subpopulation of genes. We did not observe in HCT116 cells nuclear translocation of GR{beta} and activation of this receptor by RU 486, a synthetic steroid previously reported to bind GR{beta} and to induce nuclear translocation. Our results indicate that GR{beta} has intrinsic, GR{alpha}-independent, gene-specific transcriptional activity, in addition to its previously reported dominant negative effect on GR{alpha}-induced transactivation of GRE-driven promoters.

  18. Integrated Active Fire Retrievals and Biomass Burning Emissions Using Complementary Near-Coincident Ground, Airborne and Spaceborne Sensor Data

    NASA Technical Reports Server (NTRS)

    Schroeder, Wilfrid; Ellicott, Evan; Ichoku, Charles; Ellison, Luke; Dickinson, Matthew B.; Ottmar, Roger D.; Clements, Craig; Hall, Dianne; Ambrosia, Vincent; Kremens, Robert


    Ground, airborne and spaceborne data were collected for a 450 ha prescribed fire implemented on 18 October 2011 at the Henry W. Coe State Park in California. The integration of various data elements allowed near coincident active fire retrievals to be estimated. The Autonomous Modular Sensor-Wildfire (AMS) airborne multispectral imaging system was used as a bridge between ground and spaceborne data sets providing high quality reference information to support satellite fire retrieval error analyses and fire emissions estimates. We found excellent agreement between peak fire radiant heat flux data (less than 1% error) derived from near-coincident ground radiometers and AMS. Both MODIS and GOES imager active fire products were negatively influenced by the presence of thick smoke, which was misclassified as cloud by their algorithms, leading to the omission of fire pixels beneath the smoke, and resulting in the underestimation of their retrieved fire radiative power (FRP) values for the burn plot, compared to the reference airborne data. Agreement between airborne and spaceborne FRP data improved significantly after correction for omission errors and atmospheric attenuation, resulting in as low as 5 difference between AquaMODIS and AMS. Use of in situ fuel and fire energy estimates in combination with a collection of AMS, MODIS, and GOES FRP retrievals provided a fuel consumption factor of 0.261 kg per MJ, total energy release of 14.5 x 10(exp 6) MJ, and total fuel consumption of 3.8 x 10(exp 6) kg. Fire emissions were calculated using two separate techniques, resulting in as low as 15 difference for various species

  19. Role of methionine in the active site of alpha-galactosidase from Trichoderma reesei.

    PubMed Central

    Kachurin, A M; Golubev, A M; Geisow, M M; Veselkina, O S; Isaeva-Ivanova, L S; Neustroev, K N


    alpha-Galactosidase from Trichoderma reesei when treated with H2O2 shows a 12-fold increase in activity towards p-nitrophenyl alpha-D-galactopyranoside. A similar effect is produced by the treatment of alpha-galactosidase with other non-specific oxidants: NaIO4, KMnO4 and K4S4O8. In addition to the increase in activity, the Michaelis constant rises from 0.2 to 1.4 mM, the temperature coefficient decreases by a factor of 1.5 and the pH-activity curve falls off sharply with increasing pH. Galactose (a competitive inhibitor of alpha-galactosidase; Ki 0.09 mM for the native enzyme at pH 4.4) effectively inhibits oxidative activation of the enzyme, because the observed activity changes are related to oxidation of the catalytically important methionine in the active site. NMR measurements and amino acid analysis show that oxidation to methionine sulphoxide of one of five methionines is sufficient to activate alpha-galactosidase. Binding of galactose prevents this. Oxidative activation does not lead to conversion of other H2O2-sensitive amino acid residues, such as histidine, tyrosine, tryptophan and cysteine. The catalytically important cysteine thiol group is quantitatively titrated after protein oxidative activation. Further oxidation of methionines (up to four of five residues) can be achieved by increasing the oxidation time and/or by prior denaturation of the protein. Obviously, a methionine located in the active site of alpha-galactosidase is more accessible. The oxidative-activation phenomenon can be explained by a conformational change in the active site as a result of conversion of non-polar methionine into polar methionine sulphoxide. Images Figure 10 PMID:8948456

  20. Investigating Baseline, Alternative and Copula-based Algorithm for combining Airborne Active and Passive Microwave Observations in the SMAP Context

    NASA Astrophysics Data System (ADS)

    Montzka, C.; Lorenz, C.; Jagdhuber, T.; Laux, P.; Hajnsek, I.; Kunstmann, H.; Entekhabi, D.; Vereecken, H.


    The objective of the NASA Soil Moisture Active & Passive (SMAP) mission is to provide global measurements of soil moisture and freeze/thaw states. SMAP integrates L-band radar and radiometer instruments as a single observation system combining the respective strengths of active and passive remote sensing for enhanced soil moisture mapping. Airborne instruments will be a key part of the SMAP validation program. Here, we present an airborne campaign in the Rur catchment, Germany, in which the passive L-band system Polarimetric L-band Multi-beam Radiometer (PLMR2) and the active L-band system F-SAR of DLR were flown simultaneously on the same platform on six dates in 2013. The flights covered the full heterogeneity of the area under investigation, i.e. all types of land cover and experimental monitoring sites with in situ sensors. Here, we used the obtained data sets as a test-bed for the analysis of three active-passive fusion techniques: A) The SMAP baseline algorithm: Disaggregation of passive microwave brightness temperature by active microwave backscatter and subsequent inversion to soil moisture, B), the SMAP alternative algorithm: Estimation of soil moisture by passive sensor data and subsequent disaggregation by active sensor backscatter and C) Copula-based combination of active and passive microwave data. For method C empirical Copulas were generated and theoretical Copulas fitted both on the level of the raw products brightness temperature and backscatter as well as two soil moisture products. Results indicate that the regression parameters for method A and B are dependent on the radar vegetation index (RVI). Similarly, for method C the best performance was gained by generating separate Copulas for individual land use classes. For more in-depth analyses longer time series are necessary as can obtained by airborne campaigns, therefore, the methods will be applied to SMAP data.

  1. Differences in EEG Alpha Activity between Gifted and Non-Identified Individuals: Insights into Problem Solving.

    ERIC Educational Resources Information Center

    Jausovec, Norbert


    This study examined differences in electroencephalography (EEG) alpha activity between gifted and nongifted Slovenian student-teachers (N=17 each). Gifted students showed greater left hemisphere activation than nongifted subjects in relaxed states, but lower activation during problem solving. The same pattern was observed in overall hemispheric…

  2. Active heterodimers are formed from human DNA topoisomerase II alpha and II beta isoforms.

    PubMed Central

    Biersack, H; Jensen, S; Gromova, I; Nielsen, I S; Westergaard, O; Andersen, A H


    DNA topoisomerase II is a nuclear enzyme essential for chromosome dynamics and DNA metabolism. In mammalian cells, two genetically and biochemically distinct topoisomerase II forms exist, which are designated topoisomerase II alpha and topoisomerase II beta. In our studies of human topoisomerase II, we have found that a substantial fraction of the enzyme exists as alpha/beta heterodimers in HeLa cells. The ability to form heterodimers was verified when human topoisomerases II alpha and II beta were coexpressed in yeast and investigated in a dimerization assay. Analysis of purified heterodimers shows that these enzymes maintain topoisomerase II specific catalytic activities. The natural existence of an active heterodimeric subclass of topoisomerase II merits attention whenever topoisomerases II alpha and II beta function, localization, and cell cycle regulation are investigated. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8710863

  3. Alpha1-antichymotrypsin activity correlates with and may modulate matrix metalloproteinase-9 in human acute wounds.


    Reiss, Matthew J; Han, Yuan-Ping; Garner, Warren L


    Matrix metalloproteinase-9 (MMP-9) plays a central role in many physiologic processes including acute and the chronic wounds. MMP-9 is not routinely expressed in healthy tissues but is promptly expressed as a proenzyme and converted into active enzyme after tissue injury. The mechanisms involved, including the activators and inhibitors for this enzyme in human tissue remain largely obscure. We recently identified alpha1-antichymotrypsin (alpha1-ACT), an acute phase factor, as a potent inhibitor controlling activation of pro-MMP-9 by human skin. The aim of this study is to establish the clinical relevance of the inhibitor in cutaneous wound healing. Fluids from acute burn blisters and conditioned media from skin explants of burn patients were analyzed. We observed that the presence pro-MMP-9 and its activation correlated with the proximity to and degree of injury. Early after trauma, massive levels of wound alpha1-ACT were associated with an absence of pro-MMP-9 activation. Conversely, the active MMP-9 occurs simultaneously with inactivation of alpha1-ACT. Our results suggest a role for alpha1-ACT as a physiologic inhibitor of MMP-9 activation in human wound healing. PMID:19660051

  4. The topography of alpha-band activity tracks the content of spatial working memory.


    Foster, Joshua J; Sutterer, David W; Serences, John T; Vogel, Edward K; Awh, Edward


    Working memory (WM) is a system for the online storage of information. An emerging view is that neuronal oscillations coordinate the cellular assemblies that code the content of WM. In line with this view, previous work has demonstrated that oscillatory activity in the alpha band (8-12 Hz) plays a role in WM maintenance, but the exact contributions of this activity have remained unclear. Here, we used an inverted spatial encoding model in combination with electroencephalography (EEG) to test whether the topographic distribution of alpha-band activity tracks spatial representations held in WM. Participants in three experiments performed spatial WM tasks that required them to remember the precise angular location of a sample stimulus for 1,000-1,750 ms. Across all three experiments, we found that the topographic distribution of alpha-band activity tracked the specific location that was held in WM. Evoked (i.e., activity phase-locked to stimulus onset) and total (i.e., activity regardless of phase) power across a range of low-frequency bands transiently tracked the location of the sample stimulus following stimulus onset. However, only total power in the alpha band tracked the content of spatial WM throughout the memory delay period, which enabled reconstruction of location-selective channel tuning functions (CTFs). These findings demonstrate that alpha-band activity is directly related to the coding of spatial representations held in WM and provide a promising method for tracking the content of this online memory system. PMID:26467522

  5. Comparison in different species of biliary bilirubin-IX alpha conjugates with the activities of hepatic and renal bilirubin-IX alpha-uridine diphosphate glycosyltransferases.

    PubMed Central

    Fevery, J; Van de Vijver, M; Michiels, R; Heirwegh, K P


    The bilrubin-IXalpha conjugates in bile and the activities of bilirubin-IX alpha--UDP-glycosyltransferases in liver and kidney were determined for ten species of mammals and for the chicken. 1. In the mammalian species, bilirubin-IX alpha glucuronide was the predominant bile pigment. Excretion of neutral glycosides was unimportant, except in the cat, the mouse, the rabbit and the dog, where glucose and xylose represented 12--41% of total conjugating groups bound to bilirubin-IX alpha. In chicken bile, glucoside and glucuronide conjugates were of equal importance. They probably represent only a small fraction of the total bile pigment. 2. The transferase activities in liver showed pronounced species variation. This was also apparent with regard to activation by digitonin, pH optimum and relative activities of transferases acting on either UDP-glucuronic acid or neutral UDP-sugars. 3. Man, the dog, the cat and the rat excrete bilirubin-IX alpha largely as diconjugated derivatives. In general, diconjugated bilirubin-IX alpha could also be synthesized in vitro with liver homogenate, bilirubin-IX alpha and UDP-sugar. In contrast, for the other species examined, bilirubin pigments consisted predominantly of monoconjugated bilirubin-IX alpha. Synthesis in vitro with UDP-glucuronic acid, UDP-glucose or UDP-xylose as the sugar donor led exclusively to the formation of monoconjugated bilirubin-IX alpha. 4. The transferase activities in the kidney were restricted to the cortex and were important only for the rat and the dog. No activity at all could be detected for several species, including man. 5. Comparison of the transferase activities in liver with reported values of the maximal rate of excretion in bile suggests a close linkage between conjugation and biliary secretion of bilirubin-IX alpha. PMID:407905

  6. Impairments in Background and Event-Related Alpha-Band Oscillatory Activity in Patients with Schizophrenia

    PubMed Central

    Abeles, Ilana Y.; Gomez-Ramirez, Manuel


    Studies show that patients with schizophrenia exhibit impaired responses to sensory stimuli, especially at the early stages of neural processing. In particular, patients’ alpha-band (8–14 Hz) event-related desynchronization (ERD) and visual P1 event-related potential (ERP) component tend to be significantly reduced, with P1 ERP deficits greater for visual stimuli biased towards the magnocellular system. In healthy controls, studies show that pre-stimulus alpha (background alpha) plays a pivotal role in sensory processing and behavior, largely by shaping the neural responses to incoming stimuli. Here, we address whether patients’ ERD and P1 deficits stem from impairments in pre-stimulus alpha mechanisms. To address this question we recorded electrophysiological activity in patients with schizophrenia and healthy controls while they engaged in a visual discrimination task with low, medium, and high contrast stimuli. The results revealed a significant decrease in patients’ ERDs, which was largely driven by reductions in pre-stimulus alpha. These reductions were most prominent in right-hemispheric areas. We also observed a systematic relationship between pre-stimulus alpha and the P1 component across different contrast levels. However, this relationship was only observed in healthy controls. Taken together, these findings highlight a substantial anomaly in patients’ amplitude-based alpha background activity over visual areas. The results provide further support that pre-stimulus alpha activity plays an active role in perception by modulating the neural responses to incoming sensory inputs, a mechanism that seems to be compromised in schizophrenia. PMID:24646909

  7. NOx production by lightning in Hector: first airborne measurements during SCOUT-O3/ACTIVE

    NASA Astrophysics Data System (ADS)

    Huntrieser, H.; Schlager, H.; Lichtenstern, M.; Roiger, A.; Stock, P.; Minikin, A.; Höller, H.; Schmidt, K.; Betz, H.-D.; Allen, G.; Viciani, S.; Ulanovsky, A.; Ravegnani, F.; Brunner, D.


    During the SCOUT-O3/ACTIVE field phase in November-December 2005 airborne in situ measurements were performed inside and in the vicinity of thunderstorms over northern Australia with several research aircraft (German Falcon, Russian M55 Geophysica, and British Dornier-228). Here a case study from 19 November is presented in large detail on the basis of airborne trace gas measurements (NO, NOy, CO, O3) and stroke measurements from the German LIghtning Location NETwork (LINET), set up in the vicinity of Darwin during the field campaign. The anvil outflow from three different types of thunderstorms was probed by the Falcon aircraft: 1) a continental thunderstorm developing in a tropical airmass near Darwin, 2) a mesoscale convective system (MCS) developing within the tropical maritime continent (Tiwi Islands) known as Hector, and 3) a continental thunderstorm developing in a subtropical airmass ~200 km south of Darwin. For the first time detailed measurements of NO were performed in the Hector outflow. The highest NO mixing ratios were observed in Hector with peaks up to 7 nmol mol-1 in the main anvil outflow at ~11.5-12.5 km altitude. The mean NOx (=NO+NO2) mixing ratios during these penetrations (~100 km width) varied between 2.2 and 2.5 nmol mol-1. The NOx contribution from the boundary layer (BL), transported upward with the convection, to total anvil-NOx was found to be minor (<10%). On the basis of Falcon measurements, the mass flux of lightning-produced NOx (LNOx) in the well-developed Hector system was estimated to 0.6-0.7 kg(N) s-1. The highest average stroke rate of the probed thunderstorms was observed in the Hector system with 0.2 strokes s-1 (here only strokes with peak currents ≥10 kA contributing to LNOx were considered). The LNOx mass flux and the stroke rate were combined to estimate the LNOx production rate in the different thunderstorm types. For a better comparison with other studies, LINET strokes were scaled with Lightning Imaging Sensor (LIS

  8. NOx production by lightning in Hector: first airborne measurements during SCOUT-O3/ACTIVE

    NASA Astrophysics Data System (ADS)

    Huntrieser, H.; Schlager, H.; Lichtenstern, M.; Roiger, A.; Stock, P.; Minikin, A.; Höller, H.; Schmidt, K.; Betz, H.-D.; Allen, G.; Viciani, S.; Ulanovsky, A.; Ravegnani, F.; Brunner, D.


    During the SCOUT-O3/ACTIVE field phase in November-December 2005, airborne in situ measurements were performed inside and in the vicinity of thunderstorms over northern Australia with several research aircraft (German Falcon, Russian M55 Geophysica, and British Dornier-228. Here a case study from 19 November is presented in detail on the basis of airborne trace gas measurements (NO, NOy, CO, O3) and stroke measurements from the German LIghtning Location NETwork (LINET), set up in the vicinity of Darwin during the field campaign. The anvil outflow from three different types of thunderstorms was probed by the Falcon aircraft: (1) a continental thunderstorm developing in a tropical airmass near Darwin, (2) a mesoscale convective system (MCS), known as Hector, developing within the tropical maritime continent (Tiwi Islands), and (3) a continental thunderstorm developing in a subtropical airmass ~200 km south of Darwin. For the first time detailed measurements of NO were performed in the Hector outflow. The highest NO mixing ratios were observed in Hector with peaks up to 7 nmol mol-1 in the main anvil outflow at ~11.5-12.5 km altitude. The mean NOx (=NO+NO2) mixing ratios during these penetrations (~100 km width) varied between 2.2 and 2.5 nmol mol-1. The NOx contribution from the boundary layer (BL), transported upward with the convection, to total anvil-NOx was found to be minor (<10%). On the basis of Falcon measurements, the mass flux of lightning-produced NOx (LNOx) in the well-developed Hector system was estimated to 0.6-0.7 kg(N) s-1. The highest average stroke rate of the probed thunderstorms was observed in the Hector system with 0.2 strokes s-1 (here only strokes with peak currents ≥10 kA contributing to LNOx were considered). The LNOx mass flux and the stroke rate were combined to estimate the LNOx production rate in the different thunderstorm types. For a better comparison with other studies, LINET strokes were scaled with Lightning Imaging Sensor (LIS

  9. Modulation of the chaperone-like activity of bovine alpha-crystallin.


    Clark, J I; Huang, Q L


    The effects of pantethine, glutathione, and selected chemical reagents on the anti-aggregation activity of alpha-crystallin was evaluated. Protein aggregation was monitored by light scattering of solutions of denatured beta L-crystallin or alcohol dehydrogenase (ADH). The ratios of beta L-crystallin/alpha-crystallin and ADH/alpha-crystallin were adjusted so that partial inhibition of protein aggregation at 60 degrees C or 37 degrees C, respectively, was observed and modulation of the chaperone action of alpha-crystallin could be evaluated easily with selected endogenous metabolites. Enhancement of the anti-aggregation activity in the beta L-crystallin assay was strongest with pantethine, which appeared to interact with alpha-crystallin. Enhancement of the anti-aggregation activity in the ADH assay was strongest with glutathione which appeared to interact with ADH. The results indicated that the products of common metabolic pathways can modulate the chaperone-like effects of alpha-crystallin on protein aggregation. PMID:8986785

  10. Gamma Activity Coupled to Alpha Phase as a Mechanism for Top-Down Controlled Gating

    PubMed Central

    Bonnefond, Mathilde; Jensen, Ole


    Coupling between neural oscillations in different frequency bands has been proposed to coordinate neural processing. In particular, gamma power coupled to alpha phase is proposed to reflect gating of information in the visual system but the existence of such a mechanism remains untested. Here, we recorded ongoing brain activity using magnetoencephalography in subjects who performed a modified Sternberg working memory task in which distractors were presented in the retention interval. During the anticipatory pre-distractor period, we show that the phase of alpha oscillations was coupled with the power of high (80-120Hz) gamma band activity, i.e. gamma power consistently was lower at the trough than at the peak of the alpha cycle (9-12Hz). We further show that high alpha power was associated with weaker gamma power at the trough of the alpha cycle. This result is in line with alpha activity in sensory region implementing a mechanism of pulsed inhibition silencing neuronal firing every ~100 ms. PMID:26039691

  11. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.


    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da


    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV. PMID:26773821

  12. Airborne gamma radiation measurements of soil moisture during FIFE: Activities and results

    NASA Technical Reports Server (NTRS)

    Peck, Eugene L.


    Soil moisture measurements were obtained during the summer of 1987 and 1989 near Manhattan, Kansas, using the National Weather Service (NWS) airborne gamma radiation system. A network of 24 flight lines were established over the research area. Airborne surveys were flown daily during two intensive field campaigns. The data collected was sufficient to modify the NWS standard operational method for estimating soil moisture for the Field Experiment (FIFE) flight lines. The average root mean square error of the soil moisture estimates for shorter FIFE flight lines was found to be 2.5 percent, compared with a reported value of 3.9 percent for NWS flight lines. Techniques were developed to compute soil moisture estimates for portions of the flight lines. Results of comparisons of the airborne gamma radiation soil moisture estimates with those obtained using the NASA Pushbroom Microwave Radiation (PBMR) system and hydrological model are presented. The airborne soil moisture measurements, and real averages computed using all remotely sensed and ground data, have been in support of the research of the many FIFE investigators whose overall goal was the upscale integration of models and the application of satellite remote sensing.

  13. Peroxisome proliferator-activated receptor alpha (PPARalpha) agonists down-regulate alpha2-macroglobulin expression by a PPARalpha-dependent mechanism.

    EPA Science Inventory

    Peroxisome proliferator-activated receptor alpha (PPARα) regulates transcription of genes involved both in lipid and glucose metabolism as well as inflammation. Fibrates are PPARα ligands used to normalize lipid and glucose parameters and exert anti-inflammatory effects. Fibrates...

  14. Cefoperazone prevents the inactivation of alpha(1)-antitrypsin by activated neutrophils.


    Dallegri, F; Dapino, P; Arduino, N; Bertolotto, M; Ottonello, L


    At sites of neutrophilic inflammation, tissue injury by neutrophil elastase is favored by phagocyte-induced hypochlorous acid-dependent inactivation of the natural elastase inhibitor alpha(1)-antitrypsin. In the present study, cefoperazone prevented alpha(1)-antitrypsin inactivation by neutrophils and reduced the recovery of hypochlorous acid from these cells. Moreover, the antibiotic reduced the free elastase activity in a neutrophil suspension supplemented with alpha(1)-antitrypsin without affecting the cells' ability to release elastase. These data suggest that the drug inactivates hypochlorous acid before its reaction with alpha(1)-antitrypsin, thereby permitting the antiprotease-mediated blockade of released elastase. In conclusion, cefoperazone appears to have the potential for limiting elastase-antielastase imbalances, attenuating the related tissue injury at sites of inflammation. PMID:10471586

  15. Developmental toxicity of perfluorononanoic acid is dependent on peroxisome proliferator activated receptor-alpha.

    EPA Science Inventory

    Perfluorononanoic acid (PFNA) is one of the predominant perfluoroalkyl acids in the environment and in tissues of humans and wildlife. PFNA strongly activates the mouse and human peroxisome proliferator-activated receptor-alpha (PPARα) in vitro and negatively impacts development ...

  16. Contribution of mucosal maltase-glucoamylase activities to mouse small intestinal starch alpha-glucogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Digestion of starch requires activities provided by 6 interactive small intestinal enzymes. Two of these are luminal endo-glucosidases named alpha-amylases. Four are exo-glucosidases bound to the luminal surface of enterocytes. These mucosal activities were identified as 4 different maltases. Two ma...

  17. Biological activities of 2alpha-substituted analogues of 1alpha,25-dihydroxyvitamin D3 in transcriptional regulation and human promyelocytic leukemia (HL-60) cell proliferation and differentiation.


    Takahashi, Eiji; Nakagawa, Kimie; Suhara, Yoshitomo; Kittaka, Atsushi; Nihei, Ken-ichi; Konno, Katsuhiro; Takayama, Hiroaki; Ozono, Keiichi; Okano, Toshio


    Biological activities of 2alpha-substituted 1alpha,25-dihydroxyvitamin D3 analogues were evaluated in vitro. Their binding affinity was examined with calf thymus cytosolic vitamin D receptor (VDR) and rat plasma vitamin D-binding protein (DBP). In addition, the transcriptional activity of the analogues was measured using a rat 25-hydroxyvitamin D3-24-hydroxylase gene promoter, a human osteocalcin gene promoter, and VDR-GAL4 system. This study investigated the biological activities of 2alpha-substituted analogues in comparison with 2beta-substitued analogues at the molecular level, with regard to the structural differences of alkyl, hydroxyalkyl, hydroxyalkoxy substituents at the 2-position of 1alpha,25-dihydroxyvitamin D3. PMID:17077522

  18. Metabolism of 1alpha-hydroxyvitamin D3 by cytochrome P450scc to biologically active 1alpha,20-dihydroxyvitamin D3.


    Tuckey, Robert C; Janjetovic, Zorica; Li, Wei; Nguyen, Minh N; Zmijewski, Michal A; Zjawiony, Jordan; Slominski, Andrzej


    Cytochrome P450scc (CYP11A1) metabolizes vitamin D3 to 20-hydroxyvitamin D3 as the major product, with subsequent production of dihydroxy and trihydroxy derivatives. The aim of this study was to determine whether cytochrome P450scc could metabolize 1alpha-hydroxyvitamin D3 and whether products were biologically active. The major product of 1alpha-hydroxyvitamin D3 metabolism by P450scc was identified by mass spectrometry and NMR as 1alpha,20-dihydroxyvitamin D3. Mass spectrometry of minor metabolites revealed the production of another dihydroxyvitamin D3 derivative, two trihydroxy-metabolites made via 1alpha,20-dihydroxyvitamin D3 and a tetrahydroxyvitamin D3 derivative. The Km for 1alpha-hydroxyvitamin D3 determined for P450scc incorporated into phospholipid vesicles was 1.4 mol substrate/mol phospholipid, half that observed for vitamin D3. The kcat was 3.0 mol/min/mol P450scc, 6-fold lower than that for vitamin D3. 1alpha,20-Dihydroxyvitamin D3 inhibited DNA synthesis by human epidermal HaCaT keratinocytes propagated in culture, in a time- and dose-dependent fashion, with a potency similar to that of 1alpha,25-dihydroxyvitamin D3. 1alpha,20-Dihydroxyvitamin D3 (10 microM) enhanced CYP24 mRNA levels in HaCaT keratinocytes but the potency was much lower than that reported for 1alpha,25-dihydroxyvitamin D3. We conclude that the presence of the 1-hydroxyl group in vitamin D3 does not alter the major site of hydroxylation by P450scc which, as for vitamin D3, is at C20. The major product, 1alpha,20-dihydroxyvitamin D3, displays biological activity on keratinocytes and therefore might be useful pharmacologically. PMID:19000766

  19. Active Trafficking of Alpha 1 Antitrypsin across the Lung Endothelium

    PubMed Central

    Lockett, Angelia D.; Brown, Mary Beth; Santos-Falcon, Nieves; Rush, Natalia I.; Oueini, Houssam; Oberle, Amber J.; Bolanis, Esther; Fragoso, Miryam A.; Petrusca, Daniela N.; Serban, Karina A.; Schweitzer, Kelly S.; Presson Jr., Robert G.


    The homeostatic lung protective effects of alpha-1 antitrypsin (A1AT) may require the transport of circulating proteinase inhibitor across an intact lung endothelial barrier. We hypothesized that uninjured pulmonary endothelial cells transport A1AT to lung epithelial cells. Purified human A1AT was rapidly taken up by confluent primary rat pulmonary endothelial cell monolayers, was secreted extracellularly, both apically and basolaterally, and was taken up by adjacent rat lung epithelial cells co-cultured on polarized transwells. Similarly, polarized primary human lung epithelial cells took up basolaterally-, but not apically-supplied A1AT, followed by apical secretion. Evidence of A1AT transcytosis across lung microcirculation was confirmed in vivo by two-photon intravital microscopy in mice. Time-lapse confocal microscopy indicated that A1AT co-localized with Golgi in the endothelium whilst inhibition of the classical secretory pathway with tunicamycin significantly increased intracellular retention of A1AT. However, inhibition of Golgi secretion promoted non-classical A1AT secretion, associated with microparticle release. Polymerized A1AT or A1AT supplied to endothelial cells exposed to soluble cigarette smoke extract had decreased transcytosis. These results suggest previously unappreciated pathways of A1AT bidirectional uptake and secretion from lung endothelial cells towards the alveolar epithelium and airspaces. A1AT trafficking may determine its functional bioavailablity in the lung, which could be impaired in individuals exposed to smoking or in those with A1AT deficiency. PMID:24743137

  20. Alternative catalytic anions differentially modulate human alpha-amylase activity and specificity.


    Maurus, Robert; Begum, Anjuman; Williams, Leslie K; Fredriksen, Jason R; Zhang, Ran; Withers, Stephen G; Brayer, Gary D


    A mechanistic study of the essential allosteric activation of human pancreatic alpha-amylase by chloride ion has been conducted by exploring a wide range of anion substitutions through kinetic and structural experiments. Surprisingly, kinetic studies indicate that the majority of these alternative anions can induce some level of enzymatic activity despite very different atomic geometries, sizes, and polyatomic natures. These data and subsequent structural studies attest to the remarkable plasticity of the chloride binding site, even though earlier structural studies of wild-type human pancreatic alpha-amylase suggested this site would likely be restricted to chloride binding. Notably, no apparent relationship is observed between anion binding affinity and relative activity, emphasizing the complexity of the relationship between chloride binding parameters and the activation mechanism that facilitates catalysis. Of the anions studied, particularly intriguing in terms of observed trends in substrate kinetics and their novel atomic compositions were the nitrite, nitrate, and azide anions, the latter of which was found to enhance the relative activity of human pancreatic alpha-amylase by nearly 5-fold. Structural studies have provided considerable insight into the nature of the interactions formed in the chloride binding site by the nitrite and nitrate anions. To probe the role such interactions play in allosteric activation, further structural analyses were conducted in the presence of acarbose, which served as a sensitive reporter molecule of the catalytic ability of these modified enzymes to carry out its expected rearrangement by human pancreatic alpha-amylase. These studies show that the largest anion of this group, nitrate, can comfortably fit in the chloride binding pocket, making all the necessary hydrogen bonds. Further, this anion has nearly the same ability to activate human pancreatic alpha-amylase and leads to the production of the same acarbose product

  1. Assessment of fecal bacteria with bile acid 7 alpha-dehydroxylating activity for the presence of bai-like genes.

    PubMed Central

    Doerner, K C; Takamine, F; LaVoie, C P; Mallonee, D H; Hylemon, P B


    Eubacterium sp. strain VPI 12708 has several bile acid-inducible (bai) genes which encode enzymes in the bile acid 7 alpha-dehydroxylation (7 alpha DeOH) pathway. Twelve 7 alpha DeOH-positive intestinal bacterial strains were assayed for 7 alpha DeOH activity, and 13 strains were tested for hybridization with bai genes. Cholic acid 7 alpha DeOH activity varied greatly (> 100-fold) among these strains. Southern blot experiments showed that DNA prepared from 7 of 13 strains hybridized with at least one of the bai genes from Eubacterium sp. strain VPI 12708. PMID:9055436

  2. Immunohistochemical analysis of retinoic acid receptor-alpha in human breast tumors: retinoic acid receptor-alpha expression correlates with proliferative activity.

    PubMed Central

    van der Leede, B. M.; Geertzema, J.; Vroom, T. M.; Décimo, D.; Lutz, Y.; van der Saag, P. T.; van der Burg, B.


    Retinoids are known to prevent mammary carcinogenesis in rodents and inhibit the growth of human breast cancer cells in vitro. Previously we demonstrated that retinoid inhibition of proliferation of human breast cancer cell lines is largely mediated by retinoic acid receptor (RAR)-alpha. In this study we describe for the first time the histological distribution of RAR-alpha in 33 breast lesion specimens as determined by immunostaining with RAR-alpha antibody. Nuclear staining was observed in tumor tissue and normal portions of the breast samples. Connective tissue exhibited relative uniform staining, whereas a wide range of RAR-alpha expression was found in the epithelial tumor cells. RAR-alpha protein was expressed at significantly higher levels in tumors with greater proliferative activity as determined by immunostaining with Ki-67 antibody. This suggests that RAR-alpha expression may be altered with tumor progression. Although a positive correlation between RAR-alpha mRNA levels and estrogen receptor status of breast tumors has previously been documented, we did not find such a relationship at the protein level. As RAR-alpha plays a major role in retinoid-mediated growth inhibition of human breast cancer cell in vitro, our findings suggest that patients with highly proliferating tumors could be responsive to retinoid independently of their responsiveness to (anti)-estrogens. Images Figure 1 Figure 2 PMID:8669476

  3. Catalposide is a natural agonistic ligand of peroxisome proliferator-activated receptor-{alpha}

    SciTech Connect

    Lee, Ji Hae; Jun, Hee-jin; Hoang, Minh-Hien; Jia, Yaoyao; Han, Xiang Hua; Lee, Dong-Ho; Lee, Hak-Ju; Hwang, Bang Yeon; Lee, Sung-Joon


    Highlights: Black-Right-Pointing-Pointer Catalposide is a novel ligand for PPAR{alpha}. Black-Right-Pointing-Pointer Cell stimulated with catalposide improved fatty acid uptake, regulated target genes in fatty acid {beta}-oxidation and synthesis. Black-Right-Pointing-Pointer Catalposdie reduces hepatic triacylglycerides. Black-Right-Pointing-Pointer Theses demonstrate catalposide could ameliorate hyperlipidemia and hepatic steatosis. -- Abstract: Peroxisome proliferator-activated receptor-alpha (PPAR{alpha}) is a nuclear receptor that regulates the expression of genes related to cellular lipid uptake and oxidation. Thus, PPAR{alpha} agonists may be important in the treatment of hypertriglyceridemia and hepatic steatosis. In this study, we demonstrated that catalposide is a novel natural PPAR{alpha} agonist, identified from reporter gene assay-based activity screening with approximately 900 natural plant and seaweed extracts. Results of time-resolved fluorescence resonance energy transfer analyses suggested that the compound interacted directly with the ligand-binding domain of PPAR{alpha}. Cultured hepatocytes stimulated with catalposide exhibited significantly reduced cellular triglyceride concentrations, by 21%, while cellular uptake of fatty acids was increased, by 70% (P < 0.05). Quantitative PCR analysis revealed that the increase in cellular fatty acid uptake was due to upregulation of fatty acid transporter protein-4 (+19% vs. the control) in cells stimulated with catalposide. Additionally, expression of genes related to fatty acid oxidation and high-density lipoprotein metabolism were upregulated, while that of genes related to fatty acid synthesis were suppressed. In conclusion, catalposide is hypolipidemic by activation of PPAR{alpha} via a ligand-mediated mechanism that modulates the expression of in lipid metabolism genes in hepatocytes.

  4. [Effect of adrenal stress on activity of proteinase and alpha-1-proteinase inhibitor in rats].


    Samokhina, L M; Kaliman, P A


    The effect of adrenal stress on the proteinase and alpha-1-proteinase inhibitor activities in blood serum and cytosols of the rat organs were investigated. The reliable change was marked only in the alpha-1-PI level research of lung tissue cytosol. The proteolysis suppression was revealed in the heart and kidney tissue, while the proteolysis activation was revealed in serum and less in the lung tissue cytosol. Changes in proteinase level in the myocardium and kidney tissue play the primary role in respect to those of the other research liquids under study. PMID:7747353

  5. Cross-inhibitory activity of cereal protein inhibitors against alpha-amylases and xylanases.


    Sancho, Ana I; Faulds, Craig B; Svensson, Birte; Bartolomé, Begoña; Williamson, Gary; Juge, Nathalie


    The purification and characterisation of a xylanase inhibitor (XIP-I) from wheat was reported previously. In our current work, XIP-I is also demonstrated to have the capacity to inhibit the two barley alpha-amylase isozymes (AMY1 and AMY2). XIP-I completely inhibited the activity of AMY1 and AMY2 towards insoluble Blue Starch and a soluble hepta-oligosaccharide derivative. A ternary complex was formed between insoluble starch, a catalytically inactive mutant of AMY1 (D180A), and XIP-I, suggesting that the substrate-XIP-I interaction is necessary for inhibition of barley alpha-amylases. K(i) values for alpha-amylase inhibition, however, could not be calculated due to the nonlinear nature of the inhibition pattern. Furthermore, surface plasmon resonance and gel electrophoresis did not indicate interaction between XIP-I and the alpha-amylases. The inhibition was abolished by CaCl(2), indicating that the driving force for the interaction is different from that of complexation between the barley alpha-amylase/subtilisin inhibitor (BASI) and AMY2. This is the first report of a proteinaceous inhibitor of AMY1. BASI, in addition, was demonstrated to partially inhibit the endo-1,4-beta-D-xylanase from Aspergillus niger (XylA) of glycoside hydrolase family 11. Taken together, the data demonstrate for the first time the dual target enzyme specificity of BASI and XIP-I inhibitors for xylanase and alpha-amylase. PMID:12922177

  6. Low-intensity contraction activates the alpha1-isoform of 5'-AMP-activated protein kinase in rat skeletal muscle.


    Toyoda, Taro; Tanaka, Satsuki; Ebihara, Ken; Masuzaki, Hiroaki; Hosoda, Kiminori; Sato, Kenji; Fushiki, Tohru; Nakao, Kazuwa; Hayashi, Tatsuya


    Skeletal muscle expresses two catalytic subunits, alpha1 and alpha2, of the 5'-AMP-activated protein kinase (AMPK), which has been implicated in contraction-stimulated glucose transport and fatty acid oxidation. Muscle contraction activates the alpha2-containing AMPK complex (AMPKalpha2), but this activation may occur with or without activation of the alpha1-containing AMPK complex (AMPKalpha1), suggesting that AMPKalpha2 is the major isoform responsible for contraction-induced metabolic events in skeletal muscle. We report for the first time that AMPKalpha1, but not AMPKalpha2, can be activated in contracting skeletal muscle. Rat epitrochlearis muscles were isolated and incubated in Krebs-Ringer bicarbonate buffer containing pyruvate. In muscles stimulated to contract at a frequency of 1 and 2 Hz during the last 2 min of incubation, AMPKalpha1 activity increased twofold and AMPKalpha2 activity remained unchanged. Muscle stimulation did not change the muscle AMP concentration or the AMP-to-ATP ratio. AMPK activation was associated with increased phosphorylation of Thr(172) of the alpha-subunit, the primary activation site. Muscle stimulation increased the phosphorylation of acetyl-CoA carboxylase (ACC), a downstream target of AMPK, and the rate of 3-O-methyl-d-glucose transport. In contrast, increasing the frequency (>or=5 Hz) or duration (>or=5 min) of contraction activated AMPKalpha1 and AMPKalpha2 and increased AMP concentration and the AMP/ATP ratio. These results suggest that 1) AMPKalpha1 is the predominant isoform activated by AMP-independent phosphorylation in low-intensity contracting muscle, 2) AMPKalpha2 is activated by an AMP-dependent mechanism in high-intensity contracting muscle, and 3) activation of each isoform enhances glucose transport and ACC phosphorylation in skeletal muscle. PMID:16249251

  7. TNF-alpha released by comigrating monocytes promotes transendothelial migration of activated lymphocytes.


    Green, D M; Trial, J; Birdsall, H H


    We investigated mechanisms that increase motility and transendothelial trafficking of activated lymphocytes. Freshly isolated lymphocytes stimulated with immobilized anti-CD3 for 2 h migrate into polymerized collagen in 1.99+/-0.25-fold greater numbers and across confluent endothelial monolayers in 4.8+/-0.5-fold greater numbers compared with leukocytes incubated with non-specific IgG. Activated lymphocytes form clusters with monocytes, and their increased motility was dependent on the presence of comigrating monocytes. Five lines of evidence support the idea that monocytes modulate lymphocyte motility through the release of TNF-alpha: 1) flow-cytometric analyses, using highly specific and avid mAbs to probe permeabilized whole blood leukocytes, showed that >80% of circulating monocytes contain intracellular TNF-alpha, whereas <5% contain IL-1 and none contain IL-6; 2) stimulation with immobilized anti-CD3 that was intended to activate lymphocytes also induced monocytes to release increased quantities of TNF-alpha; 3) rTNF-alpha, added in doses of 1 to 20 pg/ml to purified anti-CD3-stimulated lymphocytes, reproduced, in a dose-dependent manner, the motility-enhancing effect of adding monocytes; 4) the transient increase in the expression of TNF R-I on CD3-activated T lymphocytes parallels their transiently increased motility; and 5) addition of anti-TNF-alpha, anti-TNF R-I, anti-TNF R-II, or soluble TNF R-I decreased the motility of stimulated lymphocytes. These results suggest that T lymphocyte stimulation via the CD3-TCR complex signals nearby monocytes to release TNF-alpha, which feeds back on the lymphocytes to increase their locomotor activity. PMID:9725247

  8. Filamin A negatively regulates the transcriptional activity of p73{alpha} in the cytoplasm

    SciTech Connect

    Kim, Eun-Joo; Park, Jong-Sup; Um, Soo-Jong


    The transcription regulator p73{alpha} is structurally different from p53 in that it possesses a unique C-terminal domain, which has been implicated in transcriptional repression. To dissect the mechanism of repression by this domain, we performed a yeast two-hybrid screen of a HeLa cDNA library using residues 487-636 of p73{alpha} as bait and isolated a cDNA clone encoding the C-terminal portion (residues 2210-2647) of filamin A, a 280-kDa actin-binding protein. Additional yeast two-hybrid assays indicated that filamin A specifically interacts with the p73{alpha} C-terminus, which is lacking in p53 and p73{beta}. The interaction was confirmed by GST pull-down assays in vitro and by immunoprecipitation analysis in vivo. Immunofluorescence microscopy revealed that p73{alpha} remained in the cytoplasm in A7 melanoma cells stably expressing filamin A, whereas it was localized in the nucleus of filamin A-deficient M2 cells. Deletion of the C-terminus of p73{alpha} (residues 487-636) resulted in nuclear localization in both cell types. Consistent with our interaction data, transient co-expression of filamin A resulted in the down-regulation of p73{alpha}, but not of p53, transcriptional activity on various p53-responsive promoters. Taken together, our data suggest that p73{alpha} is sequestered in the cytoplasm by filamin A, thereby inhibiting its transcriptional activity.

  9. 20-alpha-Hydroxysteroid dehydrogenase from pseudopregnant rat ovary: obtention and characterization of a monoclonal antibody against the enzyme activity.


    De La Llosa-Hermier, M P; Nocart, M; Paly, J; Hermier, C


    The enzyme 20-alpha-hydroxysteroid dehydrogenase (20-alpha-HSD) was purified from pseudopregnant rat ovaries and used as antigen for the development of a monoclonal antibody by the hybridoma technique. Spleen cells of BALB/c mice immunized with purified 20-alpha-HSD were fused with SP2/0 mouse myeloma cells. Among the colonies of hybrid cells, one (designated mAb-HSD 11) was found to be secreting antibodies (IgM) able to inhibit 20-alpha-HSD activity. The antibody-secreting hybridome was amplified by ascitic fluid production and the monoclonal antibody purified by Bakerbond ABx procedure. Purified mAb-HSD 11 was able to inhibit 20-alpha-HSD activity in a dose-dependent manner. Studies of Michaelis constants of 20-alpha-HSD indicate that this monoclonal antibody increases the Km for 20-alpha-dihydroprogesterone and decreases the Vmax. PMID:1292619

  10. Structure-based protein engineering for alpha-amylase inhibitory activity of plant defensin.


    Lin, Ku-Feng; Lee, Tian-Ren; Tsai, Ping-Hsing; Hsu, Ming-Pin; Chen, Ching-San; Lyu, Ping-Chiang


    The structure of a novel plant defensin isolated from the seeds of the mung bean, Vigna radiate, has been determined by (1)H nuclear magnetic resonance spectroscopy. The three-dimensional structure of VrD2, the V. radiate plant defensin 2 protein, comprises an alpha-helix and one triple-stranded anti-parallel beta-sheet stabilized by four disulfide bonds. This protein exhibits neither insecticidal activity nor alpha-amylase inhibitory activity in spite of showing a similar global fold to that of VrD1, an insecticidal plant defensin that has been suggested to function by inhibiting insect alpha-amylase. Our previous study proposed that loop L3 of plant defensins is important for this inhibition. Structural analyses and surface charge comparisons of VrD1 and VrD2 revealed that the charged residues of L3 correlate with the observed difference in inhibitory activities of these proteins. A VrD2 chimera that was produced by transferring the proposed functional loop of VrD1 onto the structurally equivalent loop of VrD2 supported this hypothesis. The VrD2 chimera, which differs by only five residues compared with VrD2, showed obvious activity against Tenebrio molitor alpha-amylase. These results clarify the mode of alpha-amylase inhibition of plant defensins and also represent a possible approach for engineering novel alpha-amylase inhibitors. Plant defensins are important constituents of the innate immune system of plants, and thus the application of protein engineering to this protein family may provide an efficient method for protecting against crop losses. PMID:17444520

  11. AP-2{alpha} suppresses skeletal myoblast proliferation and represses fibroblast growth factor receptor 1 promoter activity

    SciTech Connect

    Mitchell, Darrion L.; DiMario, Joseph X.


    Skeletal muscle development is partly characterized by myoblast proliferation and subsequent differentiation into postmitotic muscle fibers. Developmental regulation of expression of the fibroblast growth factor receptor 1 (FGFR1) gene is required for normal myoblast proliferation and muscle formation. As a result, FGFR1 promoter activity is controlled by multiple transcriptional regulatory proteins during both proliferation and differentiation of myogenic cells. The transcription factor AP-2{alpha} is present in nuclei of skeletal muscle cells and suppresses myoblast proliferation in vitro. Since FGFR1 gene expression is tightly linked to myoblast proliferation versus differentiation, the FGFR1 promoter was examined for candidate AP-2{alpha} binding sites. Mutagenesis studies indicated that a candidate binding site located at - 1035 bp functioned as a repressor cis-regulatory element. Furthermore, mutation of this site alleviated AP-2{alpha}-mediated repression of FGFR1 promoter activity. Chromatin immunoprecipitation studies demonstrated that AP-2{alpha} interacted with the FGFR1 promoter in both proliferating myoblasts and differentiated myotubes. In total, these results indicate that AP-2{alpha} is a transcriptional repressor of FGFR1 gene expression during skeletal myogenesis.

  12. Cross-talk between receptors with intrinsic tyrosine kinase activity and alpha1b-adrenoceptors.

    PubMed Central

    del Carmen Medina, L; Vázquez-Prado, J; García-Sáinz, J A


    The effect of epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) on the phosphorylation and function of alpha(1b)-adrenoceptors transfected into Rat-1 fibroblasts was studied. EGF and PDGF increased the phosphorylation of these adrenoceptors. The effect of EGF was blocked by tyrphostin AG1478 and that of PDGF was blocked by tyrphostin AG1296, inhibitors of the intrinsic tyrosine kinase activities of the receptors for these growth factors. Wortmannin, an inhibitor of phosphoinositide 3-kinase, blocked the alpha(1b)-adrenoceptor phosphorylation induced by EGF but not that induced by PDGF. Inhibition of protein kinase C blocked the adrenoceptor phosphorylation induced by EGF and PDGF. The ability of noradrenaline to increase [(35)S]guanosine 5'-[gamma-thio]triphosphate ([(35)S]GTP[S]) binding in membrane preparations was used as an index of the functional coupling of the alpha(1b)-adrenoceptors and G-proteins. Noradrenaline-stimulated [(35)S]GTP[S] binding was markedly decreased in membranes from cells pretreated with EGF or PDGF. Our data indicate that: (i) activation of EGF and PDGF receptors induces phosphorylation of alpha(1b)-adrenoceptors, (ii) phosphatidylinositol 3-kinase is involved in the EGF response, but does not seem to play a major role in the action of PDGF, (iii) protein kinase C mediates this action of both growth factors and (iv) the phosphorylation of alpha(1b)-adrenoceptors induced by EGF and PDGF is associated with adrenoceptor desensitization. PMID:10947955

  13. Possible dopaminergic stimulation of locus coeruleus alpha1-adrenoceptors involved in behavioral activation.


    Lin, Yan; Quartermain, David; Dunn, Adrian J; Weinshenker, David; Stone, Eric A


    alpha(1)-Adrenoceptors of the locus coeruleus (LC) have been implicated in behavioral activation in novel surroundings, but the endogenous agonist that activates these receptors has not been established. In addition to the canonical activation of alpha(1)-receptors by norepinephrine (NE), there is evidence that dopamine (DA) may also activate certain brain alpha(1)-receptors. This study examined the contribution of DA to exploratory activity in a novel cage by determining the effect of infusion of various dopaminergic and adrenergic drugs into the mouse LC. It was found that the D2/D3 agonist, quinpirole, which selectively blocks the release of CNS DA, produced a dose-dependent and virtually complete abolition of exploration and all movement in the novel cage test. The quinpirole-induced inactivity was significantly attenuated by coinfusion of DA but not by the D1 agonist, SKF38390. Furthermore, the DA attenuation of quinpirole inactivity was blocked by coinfusion of the alpha(1)-adrenergic receptor antagonist, terazosin, but not by the D1 receptor antagonist, SCH23390. LC infusions of either quinpirole or terazosin also produced profound inactivity in DA-beta-hydroxylase knockout (Dbh -/-) mice that lack NE, indicating that their behavioral effects were not due to an alteration of the release or action of LC NE. Measurement of endogenous DA, NE, and 5HT and their metabolites in the LC during exposure to the novel cage indicated an increase in the turnover of DA and NE but not 5HT. These results indicate that DA is a candidate as an endogenous agonist for behaviorally activating LC alpha(1)-receptors and may play a role in the activation of this nucleus by novel surroundings. PMID:18435418

  14. Insecticidal activity of an alpha-amylase inhibitor-like protein resembling a putative precursor of alpha-amylase inhibitor in the common bean, Phaseolus vulgaris L.


    Ishimoto, M; Yamada, T; Kaga, A


    alpha-Amylase inhibitor (alphaAI) in the common bean, Phaseolus vulgaris L., protects seeds from insect pests such as the cowpea weevil (Callosobruchus maculatus) and the azuki bean weevil (C. chinensis). Cultivars which lack alphaAI still show resistance to both bruchids. These cultivars have a glycoprotein that reacts with anti-alphaAI-1 antibodies. The glycoprotein with a molecular mass of 29 kDa (Gp29) was purified and the encoding gene was isolated. The primary structure of Gp29 is the same as alpha-amylase inhibitor-like protein (AIL) from which the encoding gene has already been isolated. AIL resembles a putative precursor of alphaAI, even though it does not form the active inhibitor. However, AIL has some inhibitory effect on the growth of C. maculatus but not C. chinensis. The presence of AIL alone is insufficient to explain the bruchid resistance of common bean cultivars lacking alpha-AI. Common bean seeds appear to contain several factors responsible for the bruchid resistance. PMID:10366733

  15. EGF AND TGF-{alpha} motogenic activities are mediated by the EGF receptor via distinct matrix-dependent mechanisms

    SciTech Connect

    Ellis, Ian R.; Schor, Ana M.; Schor, Seth L. . E-mail:


    EGF and TGF-{alpha} induce an equipotent stimulation of fibroblast migration and proliferation. In spite of their homologous structure and ligation by the same receptor (EGFR), we report that their respective motogenic activities are mediated by different signal transduction intermediates, with p70{sup S6K} participating in EGF signalling and phospholipase C{gamma} in TGF-{alpha} signalling. We additionally demonstrate that EGF and TGF-{alpha} motogenic activities may be resolved into two stages: (a) cell 'activation' by a transient exposure to either cytokine, and (b) the subsequent 'manifestation' of an enhanced migratory phenotype in the absence of cytokine. The cell activation and manifestation stages for each cytokine are mediated by distinct matrix-dependent mechanisms: motogenetic activation by EGF requires the concomitant functionality of EGFR and the hyaluronan receptor CD44, whereas activation by TGF-{alpha} requires EGFR and integrin {alpha}v{beta}3. Manifestation of elevated migration no longer requires the continued presence of exogenous cytokine and functional EGFR but does require the above mentioned matrix receptors, as well as their respective ligands, i.e., hyaluronan in the case of EGF, and vitronectin in the case of TGF-{alpha}. In contrast, the mitogenic activities of EGF and TGF-{alpha} are independent of CD44 and {alpha}v{beta}3 functionality. These results demonstrate clear qualitative differences between EGF and TGF-{alpha} pathways and highlight the importance of the extracellular matrix in regulating cytokine bioactivity.

  16. DHEA metabolites activate estrogen receptors alpha and beta

    PubMed Central

    Michael Miller, Kristy K.; Al-Rayyan, Numan; Ivanova, Margarita M.; Mattingly, Kathleen A.; Ripp, Sharon L.; Klinge, Carolyn M.; Prough, Russell A.


    Dehydroepiandrosterone (DHEA) levels were reported to associate with increased breast cancer risk in postmenopausal women, but some carcinogen-induced rat mammary tumor studies question this claim. The purpose of this study was to determine how DHEA and its metabolites affect estrogen receptors α or β (ERα or ERβ) -regulated gene transcription and cell proliferation. In transiently transfected HEK-293 cells, androstenediol, DHEA, and DHEA-S activated ERα. In ERβ transfected HepG2 cells, androstenedione, DHEA, androstenediol, and 7-oxo DHEA stimulated reporter activity. ER antagonists ICI 182,780 (fulvestrant) and 4-hydroxytamoxifen, general P450 inhibitor miconazole, and aromatase inhibitor exemestane inhibited activation by DHEA or metabolites in transfected cells. ERβ-selective antagonist R,R-THC (R,R-cis-diethyl tetrahydrochrysene) inhibited DHEA and DHEA metabolite transcriptional activity in ERβ-transfected cells. Expression of endogenous estrogen-regulated genes: pS2, progesterone receptor, cathepsin D1, and nuclear respiratory factor-1 was increased by DHEA and its metabolites in an ER-subtype, gene, and cell-specific manner. DHEA metabolites, but not DHEA, competed with 17β-estradiol for ERα and ERβ binding and stimulated MCF-7 cell proliferation, demonstrating that DHEA metabolites interact directly with ERα and ERβ in vitro, modulating estrogen target genes in vivo. PMID:23123738

  17. Activation of alpha6-containing GABAA receptors by pentobarbital occurs through a different mechanism than activation by GABA.


    Fisher, Matthew T; Fisher, Janet L


    The GABA(A) receptors are ligand-gated chloride channels which are the targets for many clinically used sedatives, including the barbiturates. The barbiturate pentobarbital acts through multiple sites on the GABA(A) receptor. At low concentrations (muM), it acts as a positive allosteric modulator while at higher concentrations it can directly activate the receptor. This agonist action is influenced by the subunit composition of the receptor, and pentobarbital is a more effective agonist than GABA only at receptors containing an alpha6 subunit. The conformational change that translates GABA binding into channel opening is known to involve a lysine residue located in an extracellular domain between the 2nd and 3rd transmembrane domains. Mutations of this residue disrupt activation of the channel by GABA and have been linked to inherited epilepsy. Pentobarbital binds to the receptor at a different agonist site than GABA, but could use a common signal transduction mechanism to gate the channel. To address this question, we compared the effect of a mutating the homologous lysine residue in the alpha1 or alpha6 subunits (K278 or K277, respectively) to methionine on direct activation of recombinant GABA(A) receptors by GABA or pentobarbital. We found that this mutation reduced GABA sensitivity for both alpha1 and alpha6 subunits, but affected pentobarbital sensitivity only for the alpha1 subunit. This suggests that pentobarbital acts through a distinct signal transduction pathway at the alpha6 subunit, which may account for its greater efficacy compared to GABA at receptors containing this subunit. PMID:20109529

  18. Human alpha-thrombin inhibition by the active site titrant N alpha-(N,N-dimethylcarbamoyl)-alpha-azalysine p-nitrophenyl ester: a comparative kinetic and X-ray crystallographic study.


    Nardini, M; Pesce, A; Rizzi, M; Casale, E; Ferraccioli, R; Balliano, G; Milla, P; Ascenzi, P; Bolognesi, M


    Kinetics for the hydrolysis of the chromogenic active site titrant N alpha-(N,N-dimethylcarbamoyl)-alpha-azalysine p-nitrophenyl ester (Dmc-azaLys-ONp) catalyzed by bovine beta-trypsin, bovine alpha-thrombin, human alpha-thrombin, human Lys77-plasmin, human urinary kallikrein, the M(r) 33,000 and M(r) 54,000 species of human urokinase, as well as by porcine pancreatic beta-kallikrein-A and B have been obtained between pH 6.0 and 8.0, at 21.0 degrees C. Moreover, the three dimensional structure of the human alpha-thrombin-(hirugen).Dmc-azaLys acyl.enzyme complex has been analyzed and refined by X-ray crystallography at 2.0 A resolution (R-factor = 0.168). As observed for bovine beta-trypsin, the acylating inhibitor molecule is covalently bound to the Ser195 catalytic residue, filling the human alpha-thrombin S1 primary specificity subsite with its lysyl side-group. However, the carbonyl group of the scissile human alpha-thrombin.Dmc-azaLys acyl bond does not occupy properly the oxyanion binding hole. At variance from the bovine beta-trypsin.Dmc-azaLys acyl.enzyme structure, a second, not covalently bound, inhibitor molecule, partly shielded by the 60-insertion loop of human alpha-thrombin, is contacting the enzyme "aryl-binding site". PMID:8637015

  19. Peroxisome proliferator-activated receptor alpha polymorphisms and postprandial lipemia in healthy men

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peroxisome proliferator-activated receptor alpha (PPARA) is a ligand-dependent transcription factor that plays a key role in lipid and glucose homeostasis. This study evaluated whether variants of PPARA are associated with postprandial lipemia. Subjects were given a single fat load comprised of 60% ...

  20. Activation of AMPK alpha and gamma-isoform complexes in the intact ischemic rat heart

    Technology Transfer Automated Retrieval System (TEKTRAN)

    AMP-activated protein kinase (AMPK) plays a key role in modulating cellular metabolic processes. AMPK, a serine-threonine kinase, is a heterotrimeric complex of catalytic alpha-subunits and regulatory beta- and gamma-subunits with multiple isoforms. Mutations in the cardiac gamma(2)-isoform have bee...

  1. Structural basis of UDP-galactose binding by alpha-1,3-galactosyltransferase (alpha3GT): role of negative charge on aspartic acid 316 in structure and activity.


    Tumbale, Percy; Jamaluddin, Haryati; Thiyagarajan, Nethaji; Brew, Keith; Acharya, K Ravi


    alpha-1,3-Galactosyltransferase (alpha3GT) catalyzes the transfer of galactose from UDP-galactose to form an alpha 1-3 link with beta-linked galactosides; it is part of a family of homologous retaining glycosyltransferases that includes the histo-blood group A and B glycosyltransferases, Forssman glycolipid synthase, iGb3 synthase, and some uncharacterized prokaryotic glycosyltransferases. In mammals, the presence or absence of active forms of these enzymes results in antigenic differences between individuals and species that modulate the interplay between the immune system and pathogens. The catalytic mechanism of alpha3GT is controversial, but the structure of an enzyme complex with the donor substrate could illuminate both this and the basis of donor substrate specificity. We report here the structure of the complex of a low-activity mutant alpha3GT with UDP-galactose (UDP-gal) exhibiting a bent configuration stabilized by interactions of the galactose with multiple residues in the enzyme including those in a highly conserved region (His315 to Ser318). Analysis of the properties of mutants containing substitutions for these residues shows that catalytic activity is strongly affected by His315 and Asp316. The negative charge of Asp316 is crucial for catalytic activity, and structural studies of two mutants show that its interaction with Arg202 is needed for an active site structure that facilitates the binding of UDP-gal in a catalytically competent conformation. PMID:18651752

  2. Modular organization and development activity of an Arabidopsis thaliana EF-1 alpha gene promoter.


    Curie, C; Axelos, M; Bardet, C; Atanassova, R; Chaubet, N; Lescure, B


    The activity of the Arabidopsis thalana A1 EF-1 alpha gene promoter was analyzed in transgenic Arabidopsis plants. The 5' upstream sequence of the A1 gene and several promoter deletions were fused to the beta-glucuronidase (GUS) coding region. Promoter activity was monitored by quantitative and histochemical assays of GUS activity. The results show that the A1 promoter exhibits a modular organization. Sequences both upstream and downstream relative to the transcription initiation site are involved in quantitative and tissue-specific expression during vegetative growth. One upstream element may be involved in the activation of expression in meristematic tissues; the downstream region, corresponding to an intron within the 5' non-coding region (5'IVS), is important for expression in roots; both upstream and downstream sequences are required for expression in leaves, suggesting combinatorial properties of EF-1 alpha cis-regulatory elements. This notion of specific combinatorial regulation is reinforced by the results of transient expression experiments in transfected Arabidopsis protoplasts. The deletion of the 5'IVS has much more effect on expression when the promoter activity is under the control of A1 EF-1 alpha upstream sequences than when these upstream sequences were replaced by the 35S enhancer. Similarly, a synthetic oligonucleotide corresponding to an A1 EF-1 alpha upstream cis-acting element (the TEF1 box), is able to restore partially the original activity when fused to a TEF1-less EF1-alpha promoter but has no significant effect when fused to an enhancer-less 35S promoter. PMID:8492811

  3. Stimulation of NSF ATPase activity by alpha-SNAP is required for SNARE complex disassembly and exocytosis.


    Barnard, R J; Morgan, A; Burgoyne, R D


    N-ethylmaleimide-sensitive fusion protein (NSF) and alpha-SNAP play key roles in vesicular traffic through the secretory pathway. In this study, NH2- and COOH-terminal truncation mutants of alpha-SNAP were assayed for ability to bind NSF and stimulate its ATPase activity. Deletion of up to 160 NH2-terminal amino acids had little effect on the ability of alpha-SNAP to stimulate the ATPase activity of NSF. However, deletion of as few as 10 COOH-terminal amino acids resulted in a marked decrease. Both NH2-terminal (1-160) and COOH-terminal (160-295) fragments of alpha-SNAP were able to bind to NSF, suggesting that alpha-SNAP contains distinct NH2- and COOH-terminal binding sites for NSF. Sequence alignment of known SNAPs revealed only leucine 294 to be conserved in the final 10 amino acids of alpha-SNAP. Mutation of leucine 294 to alanine (alpha-SNAP(L294A)) resulted in a decrease in the ability to stimulate NSF ATPase activity but had no effect on the ability of this mutant to bind NSF. alpha-SNAP (1-285) and alpha-SNAP (L294A) were unable to stimulate Ca2+-dependent exocytosis in permeabilized chromaffin cells. In addition, alpha-SNAP (1-285), and alpha-SNAP (L294A) were able to inhibit the stimulation of exocytosis by exogenous alpha-SNAP. alpha-SNAP, alpha-SNAP (1-285), and alpha-SNAP (L294A) were all able to become incorporated into a 20S complex and recruit NSF. In the presence of MgATP, alpha-SNAP (1-285) and alpha-SNAP (L294A) were unable to fully disassemble the 20S complex and did not allow vesicle-associated membrane protein dissociation to any greater level than seen in control incubations. These findings imply that alpha-SNAP stimulation of NSF ATPase activity may be required for 20S complex disassembly and for the alpha-SNAP stimulation of exocytosis. PMID:9362506

  4. Clostridium perfringens alpha-N-acetylgalactosaminidase blood group A2-degrading activity.


    Hsieh, Hsin-Yeh; Smith, Daniel


    Enzymic modification of type A(2) erythrocyte membranes with Clostridium perfringens alpha-N-acetylgalactosaminidase was investigated. An ELISA demonstrated hydrolysis of type A(2) epitopes under conditions of red-blood-cell collection and storage. The enzyme hydrolysed the terminal N-acetyl-alpha-D-galactosamine from the blood type A(2) antigen, producing H antigen, blood group O, which is universally compatible in the ABO system. The enzyme was active in common red-cell preservative solutions at pH 6.4-7.0, at 4 degrees C, at ionic strengths found in stored red cell units and in the presence of type A plasma. These data imply that the C. perfringens alpha-N-acetylgalactosaminidase might be added directly to packed A(2) red-blood-cell units for enzymic conversion to blood type O. Further studies are warranted. PMID:12630904

  5. Structure-activity relationships of alpha-conotoxins targeting neuronal nicotinic acetylcholine receptors.


    Millard, Emma L; Daly, Norelle L; Craik, David J


    alpha-Conotoxins that target the neuronal nicotinic acetylcholine receptor have a range of potential therapeutic applications and are valuable probes for examining receptor subtype selectivity. The three-dimensional structures of about half of the known neuronal specific alpha-conotoxins have now been determined and have a consensus fold containing a helical region braced by two conserved disulfide bonds. These disulfide bonds define the two-loop framework characteristic for alpha-conotoxins, CCX(m)CX(n)C, where loop 1 comprises four residues (m = 4) and loop 2 between three and seven residues (n = 3, 6 or 7). Structural studies, particularly using NMR spectroscopy have provided an insight into the role and spatial location of residues implicated in receptor binding and biological activity. PMID:15182347

  6. Mindfulness-of-breathing exercise modulates EEG alpha activity during cognitive performance.


    Bing-Canar, Hanaan; Pizzuto, Jacquelyne; Compton, Rebecca J


    The present study investigated whether engaging in a mindful breathing exercise would affect EEG oscillatory activity associated with self-monitoring processes, based on the notion that mindfulness enhances attentional awareness. Participants were assigned to either an audio exercise in mindful breathing or an audio control condition, and then completed a Stroop task while EEG was recorded. The primary EEG measure of interest was error-related alpha suppression (ERAS), an index of self-monitoring in which alpha power is reduced, suggesting mental engagement, following errors compared to correct responses. Participants in the mindful-breathing condition showed increased alpha power during the listening exercise and enhanced ERAS during the subsequent Stroop task. These results indicate enhanced error-monitoring among those in the mindful-breathing group. PMID:27245493

  7. Synergistic activation of NF-kappaB by nontypeable Haemophilus influenzae and tumor necrosis factor alpha.


    Watanabe, Takahiro; Jono, Hirofumi; Han, Jiahuai; Lim, David J; Li, Jian-Dong


    Nontypeable Haemophilus influenzae (NTHi) is an important human pathogen causing otitis media in children and exacerbation of chronic obstructive pulmonary disease in adults. Like most other bacterial infections, NTHi infections are also characterized by inflammation, which is mainly mediated by cytokines and chemokines such as tumor necrosis factor alpha (TNF-alpha). Among a variety of transcription regulators, NF-kappaB has been shown to play a critical role in regulating the expression of large numbers of genes encoding inflammatory mediators. In review of the current studies on NF-kappaB regulation, most of them have focused on investigating how NF-kappaB is activated by a single inducer at a time. However, in bacteria-induced inflammation in vivo, multiple inducers including both exogenous and endogenous mediators are present simultaneously. A key issue that has yet to be addressed is whether the exogenous inducers such as NTHi and the endogenous factors such as TNF-alpha activate NF-kappaB in a synergistic manner. We show that NTHi and TNF-alpha, when present together, synergistically induce NF-kappaB activation via two distinct signaling pathways: NF-kappaB translocation-dependent and -independent pathways. The NF-kappaB translocation-dependent pathway involves NF-kappaB-inducing kinase-IkappaB kinase beta/gamma-dependent phosphorylation and degradation of IkappaBalpha, whereas the NF-kappaB translocation-independent pathway involves mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase kinase kinase 1-dependent activation of MAPK kinase 3/6-p38 MAPK pathway. In addition, the same signaling pathways are also involved in synergistic induction of TNF-alpha, IL-1beta, and IL-8. These studies should deepen our understanding of the molecular mechanisms underlying the combinatorial regulation of inflammation and lead to development of therapeutic strategies for NTHi-induced infections. PMID:14993593

  8. Interaction of disintegrins with the alpha IIb beta 3 receptor on resting and activated human platelets.

    PubMed Central

    McLane, M A; Kowalska, M A; Silver, L; Shattil, S J; Niewiarowski, S


    Viper venom disintegrins contain the RGD/KGD motif. They inhibit platelet aggregation and cell adhesion, but show structural and functional heterogeneity. We investigated the interaction of four prototypic disintegrins with alpha IIb beta 3 expressed on the surface of resting and activated platelets. The binding affinity (Kd) of 125I-albolabrin, 125I-echistatin, 125I-bitistatin and 125I-eristostatin toward resting platelets was 294, 153, 48 and 18 nM respectively. The Kd value for albolabrin decreased 3-fold and 6-fold after ADP- or thrombin-induced activation. The Kd values for bitistatin and echistatin also decreased with ADP, but there was no further decrease with thrombin. In contrast, eristostatin bound with the same high affinity to resting and activated platelets. The pattern of fluorescein isothiocyanate (FITC)-eristostatin and FITC-albolabrin binding to resting and activated platelets was consistent with observations using radiolabelled material. Eristostatin showed faster and more irreversible binding to platelets, and greater potency compared with albolabrin in inducing conformational neo-epitopes in beta 3. The anti-alpha IIb beta 3 monoclonal antibody OP-G2 that is RGD-dependent inhibited disintegrin binding to activated platelets more strongly than binding to resting platelets and it inhibited the binding to platelets of albolabrin more strongly than eristostatin. The specificity of disintegrin interaction with alpha IIb beta 3 was confirmed by demonstrating cross-linking of these peptides to alpha IIb beta 3 on normal platelets, but not to thrombasthenic platelets deficient in alpha IIb beta 3. Images Figure 6 PMID:8042985

  9. Type III interferon (IFN-lambda) antagonizes the antiviral activity of interferon-alpha in vitro.


    Bordi, L; Lalle, E; Lapa, D; Caglioti, C; Quartu, S; Capobianchi, M R; Castilletti, C


    Type III interferons (IFN-lambda) are the most recently discovered members of IFN family. Synergism between different IFN types is well established, but for type I and type III IFNs no conclusive evidence has been reported so far. Possible synergism/antagonism between IFN-alpha and IFN-lambda in the inhibition of virus replication (EMCV, WNV lineage 1 and 2, CHIKV and HSV-1), and in the activation of intracellular pathways of IFN response (MxA and 2'-5' OAS) was evaluated in different cell lines (Vero E6, A549 and Wish cells). The antiviral potency of IFN-lambda1 and -l2 was lower than that of IFN-alpha. When IFN-alpha and -lambda were used together, the Combination Index (CI) for virus inhibition was greater than 1 virtually for all virus/host cell systems, indicating antagonistic effect. Antagonism between IFN-alpha and -l was also observed for the induction of mRNA for both MxA and 2'-5'OAS. Elucidating the interplay between IFN-alpha and -lambda may help to better understand innate defence mechanisms against viral infections, including the molecular mechanisms underlying the influence of IL-28B polymorphisms in the response to HCV and other viral infections. PMID:24382181

  10. Alpha-Smooth Muscle Actin Expression Upregulates Fibroblast Contractile Activity

    PubMed Central

    Hinz, Boris; Celetta, Giuseppe; Tomasek, James J.; Gabbiani, Giulio; Chaponnier, Christine


    To evaluate whether α-smooth muscle actin (α-SMA) plays a role in fibroblast contractility, we first compared the contractile activity of rat subcutaneous fibroblasts (SCFs), expressing low levels of α-SMA, with that of lung fibroblasts (LFs), expressing high levels of α-SMA, with the use of silicone substrates of different stiffness degrees. On medium stiffness substrates the percentage of cells producing wrinkles was similar to that of α-SMA–positive cells in each fibroblast population. On high stiffness substrates, wrinkle production was limited to a subpopulation of LFs very positive for α-SMA. In a second approach, we measured the isotonic contraction of SCF- and LF-populated attached collagen lattices. SCFs exhibited 41% diameter reduction compared with 63% by LFs. TGFβ1 increased α-SMA expression and lattice contraction by SCFs to the levels of LFs; TGFβ-antagonizing agents reduced α-SMA expression and lattice contraction by LFs to the level of SCFs. Finally, 3T3 fibroblasts transiently or permanently transfected with α-SMA cDNA exhibited a significantly higher lattice contraction compared with wild-type 3T3 fibroblasts or to fibroblasts transfected with α-cardiac and β- or γ-cytoplasmic actin. This took place in the absence of any change in smooth muscle or nonmuscle myosin heavy-chain expression. Our results indicate that an increased α-SMA expression is sufficient to enhance fibroblast contractile activity. PMID:11553712

  11. Dual effects of alpha-arbutin on monophenolase and diphenolase activities of mushroom tyrosinase.


    Qin, Liang; Wu, Yang; Liu, Youting; Chen, Yiming; Zhang, Peng


    The effects of α-arbutin on the monophenolase and diphenolase activities of mushroom tyrosinase were investigated. The results showed that α-arbutin inhibited monophenolase activity but it activated diphenolase activity. For monophenolase activity, IC50 value was 4.5 mmol · L(-1) and 4.18 mmol · L(-1) of α-arbutin could extend the lag time from 40.5 s to 167.3 s. Alpha- arbutin is proposed to be regarded as a triphenolic substrate by the enzyme during catalyzation, leading to the suicide inactivation of the active site of tyrosinase. For diphenolase activity, α-arbutin acted as an activator and its activation mechanism was mixed type activation. To reveal such activation, it should be mainly refered to the conformational changes in tyrosinase caused by the interaction of α-arbutin with residues located at the entrance to the active site, and the decrease of the effect of suicide inactivation. PMID:25303458

  12. Quantification of different human alpha interferon subtypes and pegylated interferon activities by measuring MxA promoter activation.


    François, Catherine; Bernard, Isabelle; Castelain, Sandrine; Charleston, Bryan; Fray, Martin D; Capiod, Jean-Claude; Duverlie, Gilles


    Alpha interferons (alpha-IFNs) are potent biologically active proteins synthesized and secreted by somatic cells during viral infection. Quantification of alpha-IFN concentrations in biological samples is used for diagnosis. More recently, recombinant IFNs have been used as antiviral, antiproliferative, and immunomodulatory therapeutic agents, and particularly for the treatment of chronic hepatitis C virus infection. For this purpose, IFN has recently been coupled to polyethylene glycol (PEG) to improve the pharmacokinetic properties. The measure of alpha-IFN in biological samples from treated patients could be useful to ensure compliance to therapy and the true IFN activity in relation to viral decay during follow-up. In particular, it could be used to monitor the PEG-IFN concentration in patients treated for hepatitis C virus infection. The most frequently used test is a bioassay based on the antiviral property of the IFN, but the assay is not highly reproducible. Here, we present a reporter test based on MxA promoter activation of chloramphenicol acetyltransferase expression (Mx-CAT). MxA is an antiviral protein induced and tightly regulated by alpha-IFN. The Mx-CAT assay showed good reproducibility of 15% and was suitable to quantify PEG-IFN and numerous other alpha-IFN subtypes as well, despite a differential MxA promoter activation in relation with the subtype. A good correlation was obtained with the reporter assay and a commercial enzyme-linked immunosorbent assay on samples from treated patients. This test could be useful for monitoring IFN therapy of chronically infected hepatitis C virus-infected patients treated with the standard IFN, PEG-IFN, and probably forthcoming recombinant IFNs. PMID:16127052

  13. General Subject 1. Report to ICUMSA on the determination of commercial alpha-amylase activity by a spectrophotometric method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A report is given on a new industrial method for the determination of the activity or strength of commercial alpha-amylase at a sugarcane factory or refinery, as well as a recommendation. At the present time, the activities or strengths of commercial alpha-amylases cannot be directly compared becau...

  14. Determination of airborne cadmium in environmental tobacco smoke by instrumental neutron activation analysis with a compton suppression system.


    Landsberger, S; Larson, S; Wu, D


    Concentrations of cadmium, a toxic trace element, were measured in the indoor air of several public places where environmental tobacco smoke was present. Particulate-phase cadmium concentrations were determined by analyzing air filter samples using epithermal instrumental neutron activation analysis in conjunction with a Compton suppression gamma-ray detection system, in which the detection limit for cadmium was reduced to a few nanograms per filter. A cascade impactor and a personal filter sampler were used to collect the indoor suspended particulate matter for size-fractionated mass as well as total mass, respectively. Results show that where environmental tobacco smoke is present, cadmium concentrations are significantly higher than background and that about 80% of the cadmium found in indoor airborne particulate matter is associated with particles with aerodynamic diameters less than 1.8 microns. In one instance, airborne cadmium concentrations in a music club were found to be 38 ng/m, which is at least 30 times higher than background. PMID:8328669

  15. Delineating and Defining the Boundaries of an Active Landslide in the Rainforest of Puerto Rico Using a Combination of Airborne and Terrestrial LIDAR Data

    NASA Astrophysics Data System (ADS)

    Wang, G.; Joyce, J.; Phillips, D. A.; Shrestha, R. L.; Carter, W. E.


    Light detection and ranging (LIDAR) is a remote sensing technique that uses light, often using pulses from a laser to measure the distance to a target. Both terrestrial and airborne based LIDAR techniques have been frequently used to map landslides. Airborne LIDAR has the advantage of identifying large scarps of landslides covered by tree canopies and is widely applied in identifying historical and current active landslides hidden in forested areas. However, because landslides naturally have relatively small vertical surface deformation in the foot area, it is practically difficult to identify the margins of landslide foot area with the limited spatial resolution (few decimeters) of airborne LIDAR. Alternatively, ground-based LIDAR can achieve resolution of several centimeters and also has the advantages of being portable, repeatable, and less costly. Thus ground based LIDAR can be used to identify small deformations in landslide foot areas by differencing repeated Terrestrial Laser Scanning (TLS) surveys. This study demonstrates a method of identifying the superficial boundaries as well as the bottom boundary (sliding plane) of an active landslide in National Rainforest Park, Puerto Rico, USA, using the combination of ground based and airborne LIDAR data. The method of combining terrestrial and airborne LIDAR data can be used to study landslides in other regions. This study indicates that intensity and density of laser point clouds are remarkably useful in identifying superficial boundaries of landslides.

  16. Characterization of peroxisome proliferator-activiated receptor alpha (PPARalpha)-independent effects of PPARalpha activators in the rodent liver: Di(2-ethylehexyl) phthalate activates the constitutive activated receptor

    EPA Science Inventory

    Peroxisome proliferator chemicals (PPC) are thought to mediate their effects in rodents on hepatocyte growth and liver cancer through the nuclear receptor peroxisome proliferator-activated receptor alpha (PPARalpha). Recent studies indicate that the plasticizer di-2-ethylhexyl ph...

  17. The activation mechanism of alpha1beta2gamma2S and alpha3beta3gamma2S GABAA receptors.


    Keramidas, Angelo; Harrison, Neil L


    The alpha1beta2gamma2 and alpha3beta3gamma2 are two isoforms of gamma-aminobutyric acid type A (GABAA) receptor that are widely distributed in the brain. Both are found at synapses, for example in the thalamus, where they mediate distinctly different inhibitory postsynaptic current profiles, particularly with respect to decay time. The two isoforms were expressed in HEK293 cells, and single-channel activity was recorded from outside-out patches. The kinetic characteristics of both isoforms were investigated by analyzing single-channel currents over a wide range of GABA concentrations. Alpha1beta2gamma2 channels exhibited briefer active periods than alpha3beta3gamma2 channels over the entire range of agonist concentrations and had lower intraburst open probabilities at subsaturating concentrations. Activation mechanisms were constructed by fitting postulated schemes to data recorded at saturating and subsaturating GABA concentrations simultaneously. Reaction mechanisms were ranked according to log-likelihood values and how accurately they simulated ensemble currents. The highest ranked mechanism for both channels consisted of two sequential binding steps, followed by three conducting and three nonconducting configurations. The equilibrium dissociation constant for GABA at alpha3beta3gamma2 channels was approximately 2.6 microM compared with approximately 19 microM for alpha1beta2gamma2 channels, suggesting that GABA binds to the alpha3beta3gamma2 channels with higher affinity. A notable feature of the mechanism was that two consecutive doubly liganded shut states preceded all three open configurations. The lifetime of the third shut state was briefer for the alpha3beta3gamma2 channels. The longer active periods, higher affinity, and preference for conducting states are consistent with the slower decay of inhibitory currents at synapses that contain alpha3beta3gamma2 channels. The reaction mechanism we describe here may also be appropriate for the analysis of other

  18. Impaired coactivator activity of the Gly{sub 482} variant of peroxisome proliferator-activated receptor {gamma} coactivator-1{alpha} (PGC-1{alpha}) on mitochondrial transcription factor A (Tfam) promoter

    SciTech Connect

    Choi, Yon-Sik; Hong, Jung-Man; Lim, Sunny; Ko, Kyung Soo; Pak, Youngmi Kim . E-mail:


    Mitochondrial dysfunction may cause diabetes or insulin resistance. Peroxisome proliferation-activated receptor-{gamma} (PPAR-{gamma}) coactivator-1 {alpha} (PGC-1{alpha}) increases mitochondrial transcription factor A (Tfam) resulting in mitochondrial DNA content increase. An association between a single nucleotide polymorphism (SNP), G1444A(Gly482Ser), of PGC-1{alpha} coding region and insulin resistance has been reported in some ethnic groups. In this study, we investigated whether a change of glycine to serine at codon 482 of PGC-1{alpha} affected the Tfam promoter activity. The cDNA of PGC-1{alpha} variant bearing either glycine or serine at 482 codon was transfected into Chang human hepatocyte cells. The PGC-1{alpha} protein bearing glycine had impaired coactivator activity on Tfam promoter-mediated luciferase. We analyzed the PGC-1{alpha} genotype G1444A and mitochondrial DNA (mtDNA) copy number from 229 Korean leukocyte genomic DNAs. Subjects with Gly/Gly had a 20% lower amount of peripheral blood mtDNA than did subjects with Gly/Ser and Ser/Ser (p < 0.05). No correlation was observed between diabetic parameters and PGC-1{alpha} genotypes in Koreans. These results suggest that PGC-1{alpha} variants with Gly/Gly at 482nd amino acid may impair the Tfam transcription, a regulatory function of mitochondrial biogenesis, resulting in dysfunctional mtDNA replication.

  19. The use of the long-range alpha detector (LRAD) for alpha emission surveys at active and inactive firing sites

    SciTech Connect

    Mason, C.F.V.; Allander, K.S.; Bounds, J.A.; Garner, S.E.; Walter, K.J.


    Surveys were carried out at five different firing sites at Los Alamos National Laboratory to measure residual alpha emissions in earth contaminated with natural and depleted uranium. This contamination is caused by controlled experimental explosions during testing of the non fissile components of nuclear weapons. Two conclusions were reached: the first is that post shot clearing of the experimental areas is effective at removing contamination and the second is that the diminution of alpha emissions due to aging is small.

  20. Fast skeletal muscle troponin I is a co-activator of estrogen receptor-related receptor {alpha}

    SciTech Connect

    Li Yuping; Chen Bin; Chen Jian; Lou Guiyu; Chen Shiuan; Zhou Dujin


    ERR{alpha} (estrogen receptor-related receptor {alpha}) is a member of the nuclear receptor superfamily. To further our understanding of the detailed molecular mechanism of transcriptional regulation by ERR{alpha}, we searched for ERR{alpha}-interacting proteins using a yeast two-hybrid system by screening a human mammary gland cDNA expression library with the ligand-binding domain (LBD) of ERR{alpha} as the 'bait'. Fast skeletal muscle troponin I (TNNI2), along with several known nuclear receptor co-activators, were isolated. We demonstrated that TNNI2 localizes to the cell nucleus and interacts with ERR{alpha} in co-immunoprecipitation experiments. GST pull-down assays also revealed that TNNI2 interacts directly with ERR{alpha}. Through luciferase reporter gene assays, TNNI2 was found to enhance the transactivity of ERR{alpha}. Combining mutagenesis and yeast two-hybrid assays, we mapped the ERR{alpha}-interacting domain on TNNI2 to a region encompassing amino acids 1-128. These findings reveal a new function for TNNI2 as a co-activator of ERR{alpha}.

  1. Inhibition of NF-kappaB activity by plasmid expressed alphaMSH peptide.


    Etemad-Moghadam, Bijan; Chen, Hongmin; Yin, Peng; Aziz, Nazneen; Hedley, Mary Lynne


    Alpha-Melanocyte Stimulating Hormone (alphaMSH) is a neuroimmunomodulatory peptide with remarkable anti-inflammatory properties. Daily or twice daily administration of the peptide reduces the symptoms of several inflammatory animal disease models and the peptide has demonstrated safety in human trials. Unfortunately, the pharmacokinetics of peptide delivery are not favorable from the pharmaceutical perspective. For this reason, plasmid-based vectors were created that constitutively express the immunomodulatory peptide. The fusion constructs encode the 13 amino acids of alphaMSH in frame with the first domain of serum albumin, separated by a linker and furin cleavage sites. The fusion proteins were expressed and processed in human fetal kidney (293) cells. Supernatant from B16/F10 cells transfected with the constructs stimulated secretion of melanin from melanocytes. Furthermore, transfected cytoskeletal muscle (Sol8) cells secreted bioactive alphaMSH that reduced NF-kappaB-mediated transcriptional activation of a luciferase reporter gene. The activity of these vectors provides tools and the impetus for testing the constructs in several animal models of chronic inflammation. PMID:11960637

  2. Sounds elicit relative left frontal alpha activity in 2-month-old infants

    PubMed Central

    Mai, Xiaoqin; Xu, Lin; Li, Mingyan; Shao, Jie; Zhao, Zhengyan; Lamm, Connie; Fox, Nathan A.; Nelson, Charles A.; Lozoff, Betsy


    As one kind of sounds, human voices are important for language acquisition and human-infant relations. Human voices have positive effects on infants, e.g., soothe infants and evoke an infant's smile. Increased left relative to right frontal alpha activity as assessed by the electroencephalogram (EEG) is considered to reflect approach-related emotions. In the present study, we recorded the EEG in thirty-eight 2-month-old infants during a baseline period and then while they listened to sounds, i.e., human voices. Infants displayed increased relative left frontal alpha activity in response to sounds compared to the baseline condition. These results suggest that sounds can elicit relative left frontal activity in young infants, and that this approach-related emotion presents early in life. PMID:25242501

  3. Structural requirements of position A alpha-157 in fibrinogen for the fibrin-induced rate enhancement of the activation of plasminogen by tissue-type plasminogen activator.

    PubMed Central

    Schielen, J G; Adams, H P; Voskuilen, M; Tesser, G J; Nieuwenhuizen, W


    The sequence fibrinogen-A alpha-(148-160) can mimic part of the fibrin-induced rate enhancement of the activation of plasminogen by tissue-type plasminogen activator. Previously we have reported that the lysine residue at position A alpha-157 is crucial. During our further investigations on A alpha-157 we found that lysine at position A alpha-157 may be replaced by glutamic acid. This unexpected finding prompted us to re-investigate the requirements of this position. We prepared analogues of A alpha-(148-160) in which the lysine residue at position A alpha-157 was replaced by lysine derivatives (acetyl-lysine, benzyloxycarbonyl-lysine and methanesulphonylethyloxycarbonyl-lysine), acidic residues (aspartic acid and glutamic acid), basic residues (arginine and ornithine), polar residues (glutamine and methanesulphonylethyloxycarbonylornithine), apolar residues (alanine, valine, norleucine and glutamic acid 4-nitrobenzyl ester) and glycine. These analogues were tested for their stimulatory activity. When aspartic acid, glutamic acid 4-nitrobenzyl ester or norleucine is present at position A alpha-157 in A alpha-(148-160) virtually all stimulatory capacity is lost. With valine at position A alpha-157 the stimulatory activity is marginal. None of the other replacements at position A alpha-157 caused loss of rate-enhancing properties. From these results we conclude that for the rate-enhancing effect of A alpha-(148-160) the side chain of the amino acid residue at position A alpha-157 must fulfill certain requirements: there must be one (as in alanine) or no (as in glycine) carbon atom in the side chain, or at least two carbon atoms and a polar group (charged or uncharged) to which a rather bulky group (such as the benzyloxycarbonyl group) or a polar group (such as the methanesulphonylethyloxycarbonyl group) may be attached. The highest activity [even higher than native A alpha-(148-160)] was obtained with ornithine, methanesulphonylethyloxycarbonylornithine or

  4. Changes in alpha-L-arabinofuranosidase activity in peel and pulp of banana (Musa sp.) fruits during ripening and softening.


    Zhuang, Jun-Ping; Su, Jing; Li, Xue-Ping; Chen, Wei-Xin


    Arabinose is one of the most dynamic cell wall glycosyl residues released during fruit ripening, alpha-L-arabinofuranosidase (alpha-Arab) are major glycosidases that may remove arabinose units from fruit cell wall polysaccharides. To find out whether alpha-Arab plays important roles in banana fruit softening, the enzyme activities in peel and pulp, fruit firmness, respiration rate and ethylene release rate were assayed during banana softening. The results showed that alpha-Arab activities in banana pulp and peel increased slightly at the beginning of storage and reached their maxima when the fruit firmness decreased drastically, alpha-Arab activity increased by more than ten folds in both pulp and peel during ripening and alpha-Arab activities were higher in pulp than in peel. Treatment of banana fruits with ethylene absorbent postponed the time of reaching of its maxima of respiration and ethylene, enhanced the firmness of pup and decreased alpha-Arab activity in the peel and pulp. These results suggest that alpha-Arab induced the decrease of fruit firmness and played an important role in banana fruit softening, and its activity was regulated by ethylene. PMID:17452798

  5. Immunotoxicity of perfluorooctanoic acid and perfluorooctane sulfonate and the role of peroxisome proliferator-activated receptor alpha

    EPA Science Inventory

    Peroxisome proliferators, including perfluorooctanoic acid (PFOA), are environmentally widespread and persistent and multiple toxicities have been reported in experimental animals and humans. These compounds trigger biological activity via activation of the alpha isotype of pero...

  6. Tumour necrosis factor (TNF-alpha) in leishmaniasis. II. TNF-alpha-induced macrophage leishmanicidal activity is mediated by nitric oxide from L-arginine.

    PubMed Central

    Liew, F Y; Li, Y; Millott, S


    Peritoneal macrophages from CBA mice incubated with recombinant murine tumour necrosis factor (TNF-alpha) are effective in killing the protozoa parasite Leishmania major in vitro. The leishmanicidal activity is directly correlated with the level of nitrite (NO2-) in the culture supernatants. The killing of intracellular parasites can be completely inhibited by L-NG-monomethyl arginine (L-NMMA), a specific inhibitor of the L-arginine:nitric oxide (NO) pathway. The level of NO2-, which is also a measurement of NO production, in the culture supernatant of TNF-alpha-activated macrophages can be progressively decreased to basal level with increasing concentrations of L-NMMA, but not with its D-enantiomer, D-NMMA. These data demonstrate that NO is an important effector mechanism in the TNF-alpha-induced macrophage killing of intracellular protozoa. PMID:2279740

  7. Spatial and temporal relationships of electrocorticographic alpha and gamma activity during auditory processing.


    Potes, Cristhian; Brunner, Peter; Gunduz, Aysegul; Knight, Robert T; Schalk, Gerwin


    Neuroimaging approaches have implicated multiple brain sites in musical perception, including the posterior part of the superior temporal gyrus and adjacent perisylvian areas. However, the detailed spatial and temporal relationship of neural signals that support auditory processing is largely unknown. In this study, we applied a novel inter-subject analysis approach to electrophysiological signals recorded from the surface of the brain (electrocorticography (ECoG)) in ten human subjects. This approach allowed us to reliably identify those ECoG features that were related to the processing of a complex auditory stimulus (i.e., continuous piece of music) and to investigate their spatial, temporal, and causal relationships. Our results identified stimulus-related modulations in the alpha (8-12 Hz) and high gamma (70-110 Hz) bands at neuroanatomical locations implicated in auditory processing. Specifically, we identified stimulus-related ECoG modulations in the alpha band in areas adjacent to primary auditory cortex, which are known to receive afferent auditory projections from the thalamus (80 of a total of 15,107 tested sites). In contrast, we identified stimulus-related ECoG modulations in the high gamma band not only in areas close to primary auditory cortex but also in other perisylvian areas known to be involved in higher-order auditory processing, and in superior premotor cortex (412/15,107 sites). Across all implicated areas, modulations in the high gamma band preceded those in the alpha band by 280 ms, and activity in the high gamma band causally predicted alpha activity, but not vice versa (Granger causality, p<1e(-8)). Additionally, detailed analyses using Granger causality identified causal relationships of high gamma activity between distinct locations in early auditory pathways within superior temporal gyrus (STG) and posterior STG, between posterior STG and inferior frontal cortex, and between STG and premotor cortex. Evidence suggests that these

  8. Alpha-thujone (the active component of absinthe): gamma-aminobutyric acid type A receptor modulation and metabolic detoxification.


    Höld, K M; Sirisoma, N S; Ikeda, T; Narahashi, T; Casida, J E


    Alpha-thujone is the toxic agent in absinthe, a liqueur popular in the 19th and early 20th centuries that has adverse health effects. It is also the active ingredient of wormwood oil and some other herbal medicines and is reported to have antinociceptive, insecticidal, and anthelmintic activity. This study elucidates the mechanism of alpha-thujone neurotoxicity and identifies its major metabolites and their role in the poisoning process. Four observations establish that alpha-thujone is a modulator of the gamma-aminobutyric acid (GABA) type A receptor. First, the poisoning signs (and their alleviation by diazepam and phenobarbital) in mice are similar to those of the classical antagonist picrotoxinin. Second, a strain of Drosophila specifically resistant to chloride channel blockers is also tolerant to alpha-thujone. Third, alpha-thujone is a competitive inhibitor of [(3)H]ethynylbicycloorthobenzoate binding to mouse brain membranes. Most definitively, GABA-induced peak currents in rat dorsal root ganglion neurons are suppressed by alpha-thujone with complete reversal after washout. alpha-Thujone is quickly metabolized in vitro by mouse liver microsomes with NADPH (cytochrome P450) forming 7-hydroxy-alpha-thujone as the major product plus five minor ones (4-hydroxy-alpha-thujone, 4-hydroxy-beta-thujone, two other hydroxythujones, and 7,8-dehydro-alpha-thujone), several of which also are detected in the brain of mice treated i.p. with alpha-thujone. The major 7-hydroxy metabolite attains much higher brain levels than alpha-thujone but is less toxic to mice and Drosophila and less potent in the binding assay. The other metabolites assayed are also detoxification products. Thus, alpha-thujone in absinthe and herbal medicines is a rapid-acting and readily detoxified modulator of the GABA-gated chloride channel. PMID:10725394

  9. Separation of functional domains for the alpha-1,4 and alpha-1,6 hydrolytic activities of a Bacillus amylopullulanase by limited proteolysis with papain.


    Ara, K; Igarashi, K; Hagihara, H; Sawada, K; Kobayashi, T; Ito, S


    An amylopullulanase (APase) from alkalophilic Bacillus sp. KSM-1378 hydrolyzes both alpha-1,6 linkages in pullulan and alpha-1,4 linkages in other polysaccharides, each maximally active at an alkaline pH, to generate oligosaccharides. We analyzed proteolytic fragments that were produced by exposing pure APase to various proteases, to identify its catalytic domain(s). The intact, pure 210-kDa APase was partially digested with papain for a short time, yielding simultaneously two smaller non-overlapping active fragments, designated amylose-hydrolyzing fragment (AHF114, 114 kDa) and pullulan-hydrolyzing fragment (PHF102, 102 kda). The two truncated protein fragments, each containing a single catalytic domain, were purified to homogeneity. The purified AHF114 and PHF102 had similar enzymatic properties to the amylase and pullulanase activities, respectively, of intact APase. The partial amino-terminal sequences of APase and AHF114 were both Glu-Thr-Gly-Asp-Lys-Arg-Ile-Glu-Phe-Ser-Tyr-Glu-Arg-Pro and that of PHF102 was Thr-Val-Pro-Leu-Ala-Leu-Val-Ser-Gly-Glu-Val-Leu-Ser-Asp-Lsy-Leu. These results were direct evidence that the alpha-1,6 and alpha-1,4 hydrolytic activities were associated with two different active sites in this novel enzyme. Our alkaline APase is obviously a "biheaded enzyme". PMID:8829530

  10. Phase I Rinal Report: Ultra-Low Background Alpha Activity Counter

    SciTech Connect

    Warburton, W.K.


    signal processor we easily distinguish between these two risetimes and thereby count only alpha particles emitted by the sample. Alpha particles emitted from the sample tray are absorbed in the rear of the sample, so the tray's emissivity does not contribute to the background either. Extensions of the method to the counter's sidewalls similarly allow us to reject alpha particles emitted from the sidewalls. We can thus able obtain background rates over a factor of 1000 lower than in conventional instruments without active background rejection. Extending this principle to count at the 0.00001 alpha/cm{sup 2}/hour, level encounters difficulties because there will typically be only 2.4 alpha particles per square meter per day. Since about 6 counts are required to measure activity at the 95% confidence level, large sample areas are required to make measurements in reasonable times. Unfortunately, increasing the counter's anode area to a square meter raises its capacitance so much that the preamplifier noise levels swamp the alpha particle signals and make counting impossible. In this SBIR we worked to solve this dilemma by segmenting the single large area electrode into several smaller, lower capacitance electrodes that could still detect the alpha particles reliably. Each electrode would have its own electronic and we would capture signals from all of them in coincidence (since an alpha track might well deposit charge on more than one electrode), a technique in which XIA is experienced. Therefore, in Phase I we worked to show proof of principle by subdividing our original 1,800 cm{sup 2} electrode into 4 square segments, each 625 cm{sup 2} and demonstrating that signal noise on individual channels reduced as expected. Because the Phase II counter with a 1 m{sup 2} segmented anode would require 16 segments plus a segmented guard as well, we also designed low cost signal processing electronics to instrument it in Phase II. Our Phase I effort met our major proof of principle

  11. Time-course comparison of xenobiotic activators of CAR and PPAR{alpha} in mouse liver

    SciTech Connect

    Ross, Pamela K.; Woods, Courtney G.; Bradford, Blair U.; Kosyk, Oksana; Gatti, Daniel M.; Cunningham, Michael L.; Rusyn, Ivan


    Constitutive androstane receptor (CAR) and peroxisome proliferator activated receptor (PPAR){alpha} are transcription factors known to be primary mediators of liver effects, including carcinogenesis, by phenobarbital-like compounds and peroxisome proliferators, respectively, in rodents. Many similarities exist in the phenotypes elicited by these two classes of agents in rodent liver, and we hypothesized that the initial transcriptional responses to the xenobiotic activators of CAR and PPAR{alpha} will exhibit distinct patterns, but at later time-points these biological pathways will converge. In order to capture the global transcriptional changes that result from activation of these nuclear receptors over a time-course in the mouse liver, microarray technology was used. First, differences in basal expression of liver genes between C57Bl/6J wild-type and Car-null mice were examined and 14 significantly differentially expressed genes were identified. Next, mice were treated with phenobarbital (100 mg/kg by gavage for 24 h, or 0.085% w/w diet for 7 or 28 days), and liver gene expression changes with regards to both time and treatment were identified. While several pathways related to cellular proliferation and metabolism were affected by phenobarbital in wild-type mice, no significant changes in gene expression were found over time in the Car-nulls. Next, we determined commonalities and differences in the temporal response to phenobarbital and WY-14,643, a prototypical activator of PPAR {alpha}. Gene expression signatures from livers of wild-type mice C57Bl6/J mice treated with PB or WY-14,643 were compared. Similar pathways were affected by both compounds; however, considerable time-related differences were present. This study establishes common gene expression fingerprints of exposure to activators of CAR and PPAR{alpha} in rodent liver and demonstrates that despite similar phenotypic changes, molecular pathways differ between classes of chemical carcinogens.

  12. A comparative study of the activation of protein kinase C alpha by different diacylglycerol isomers.


    Sánchez-Piñera, P; Micol, V; Corbalán-García, S; Gómez-Fernández, J C


    The lipid activation of protein kinase C alpha (PKC alpha) has been studied by comparing the activation capacity of different 1, 2-diacylglycerols and 1,3-diacylglycerols incorporated into mixed micelles or vesicles. Unsaturated 1,2-diacylglycerols were, in general, more potent activators than saturated ones when 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoserine (POPS)/Triton X-100 mixed micelles and pure POPS vesicles were used. In contrast, these differences were not observed when 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/POPS (4:1, molar ratio) vesicles were used. Diacylglycerols bearing short fatty acyl chains showed a very high activation capacity, however, the capacity was less in mixed micelles. Furthermore, 1, 2-diacylglycerols had a considerably higher activating capacity than 1,3-diacylglycerols in POPS/Triton X-100 mixed micelles and in POPC/POPS vesicles. However, the differences between the two types of diacylglycerols were smaller when pure POPS vesicles were used. Differential scanning calorimetry (DSC) showed that POPC/POPS membrane samples containing diacylglycerols had endothermic transitions in the presence of 200 microM Ca2+ and 5 mM Mg2+. Transitions were not detected when using pure POPS vesicles due to the formation of dehydrated phases as demonstrated by FTIR (Fourier-transform infrared) spectroscopy. PKC alpha binding studies, performed by differential centrifugation in the presence of 200 microM Ca2+ and 5 mM Mg2+, showed that 1,2-sn-dioleoylglycerol (1, 2-DOG) was more effective than 1,3-dioleoylglycerol (1,3-DOG) in promoting binding to POPC/POPS vesicles. However, when pure POPS vesicles were used, PKC alpha was able to bind to membranes containing either 1,2-DOG or 1,3-DOG to the same extent. PMID:9895281

  13. Intercomparison of activity size distributions of thoron progeny by alpha- and gamma-counting methods.


    Cheng, Y S; Yu, C C; Tu, K W


    It is difficult to calibrate sampling devices using radon or thoron progeny or particles measuring 1-4 nm; therefore, an interlaboratory comparison is important to verify the performance of graded diffusion batteries for the activity size distributions of the "unattached" progeny. This paper describes the results of an interlaboratory comparison of 220Rn progeny size distributions using graded diffusion batteries by alpha- and gamma-counting methods with different data inversion schemes. Graded diffusion batteries designed at the Inhalation Toxicology Research Institute and at the Environmental Measurement Laboratory were used in the study. Screens and backup filters from the Environmental Measurement Laboratory-graded diffusion batteries were counted simultaneously in alpha counters for total alpha activities, and those of the Inhalation Toxicology Research Institute-graded diffusion batteries were counted in a gamma detector for gamma activities from 212Pb. Because of the different counting methods and data analysis procedures used, this interlaboratory study of 220Rn progeny allows a more rigorous way of testing instrument performance. 212Pb particles generated in well-controlled environments of oxygen, nitrogen, or oxygen with 1 ppm of nitrogen oxide were measured. In general, good agreement in activity size distributions was obtained from these two methods. Some differences observed in individual size spectra were attributable to the data inversion programs used in each laboratory. When the data were analyzed by the same computer program, most differences disappeared. PMID:8253581

  14. Brain correlates underlying creative thinking: EEG alpha activity in professional vs. novice dancers.


    Fink, Andreas; Graif, Barbara; Neubauer, Aljoscha C


    Neuroscientific research on creativity has revealed valuable insights into possible brain correlates underlying this complex mental ability domain. However, most of the studies investigated brain activity during the performance of comparatively simple (verbal) type of tasks and the majority of studies focused on samples of the normal population. In this study we investigate EEG activity in professional dancers (n=15) who have attained a high level of expertise in this domain. This group was compared with a group of novices (n=17) who have only basic experience in dancing and completed no comprehensive training in this field. The EEG was recorded during performance of two different dancing imagery tasks which differed with respect to creative demands. In the first task participants were instructed to mentally perform a dance which should be as unique and original as possible (improvisation dance). In the waltz task they were asked to imagine dancing the waltz, a standard dance which involves a sequence of monotonous steps (lower creative demands). In addition, brain activity was also measured during performance of the Alternative Uses test. We observed evidence that during the generation of alternative uses professional dancers show stronger alpha synchronization in posterior parietal brain regions than novice dancers. During improvisation dance, professional dancers exhibited more right-hemispheric alpha synchronization than the group of novices did, while during imagining dancing the waltz no significant group differences emerged. The findings complement and extend existing findings on the relationship between EEG alpha activity and creative thinking. PMID:19269335

  15. 5-Azacytidine treatment of HA-A melanoma cells induces Sp1 activity and concomitant transforming growth factor alpha expression.

    PubMed Central

    Shin, T H; Paterson, A J; Grant, J H; Meluch, A A; Kudlow, J E


    Evidence indicates DNA methylation as a part of the regulatory machinery controlling mammalian gene expression. The human melanoma cell line HA-A expresses low levels of transforming growth factor alpha (TGF-alpha). TGF-alpha mRNA accumulated, however, in response to DNA demethylation induced by a nucleoside analog, 5-azacytidine (5-azaC). The importance of DNA methylation in the TGF-alpha promoter region was examined by a transient transfection assay with luciferase reporter plasmids containing a portion of the TGF-alpha promoter. 5-azaC treatment of HA-A cells before the transfection caused a significant increase in the luciferase activity. Since input plasmids were confirmed to remain unmethylated, DNA demethylation of the TGF-alpha promoter itself does not account for the observed increase in TGF-alpha mRNA. Using an electrophoretic mobility shift assay, enhanced formation of protein-TGF-alpha promoter complex was detected in response to 5-azaC treatment. This 5-azaC-induced complex was shown to contain the transcription factor Sp1 by the following criteria: the protein-DNA complex formed on the TGF-alpha promoter contained immunoreactive Sp1; the mobility of the complex in an electrophoretic mobility shift assay was similar to that formed by recombinant Sp1; and DNase I footprinting analysis demonstrated that the 5-azaC-induced complex produced a footprint on the TGF-alpha promoter identical to that of authentic Sp1. These observations suggest that 5-azaC induces TGF-alpha expression by augmenting the Sp1 activity. However, neither the Sp1 mRNA nor its protein was induced by 5-azaC. These results suggest that in HA-A cells, TGF-alpha expression is down-modulated by DNA methylation. In addition, this process may involve the specific regulation of Sp1 activity without altering the amount of the transcription factor. Images PMID:1380648

  16. Scanning L-Band Active Passive (SLAP)—FLIGHT Results from a New Airborne Simulator for Smap

    NASA Astrophysics Data System (ADS)

    Kim, E. J.; Faulkner, T.; Wu, A.; Patel, H.


    1. Introduction and BackgroundThis paper introduces a new NASA airborne instrument, the Scanning L-band Active Passive (SLAP), which is specially tailored to simulate SMAP. 2. Description of SLAPSLAP has both passive (radiometer) and active (radar) microwave L-band imaging capabilities. The radiometer observes at 1.4 GHz using duplicate front end hardware from the SMAP satellite radiometer. It also includes a duplicate of the digital backend development unit for SMAP, thus the novel Radio Frequency Interference (RFI) detection and mitigation features and algorithms for SMAP are duplicated with very high fidelity in SLAP. The digital backend provides 4-Stokes polarization capability. The real-aperture radar operates in the 1215-1300 MHz band with quad-pol capability. Radar and radiometer share one antenna via diplexers that are spare units from the Aquarius satellite instrument. 3. Flight ResultsSLAP's initial flights were conducted in Dec 2013 over the eastern shore of Maryland and successfully demonstrated radiometer imaging over 2 full SMAP 36x36 km grid cells at 1km resolution within 3 hrs, easily meeting the SMAP post-launch cal/val airborne mapping requirements. A second flight on the same day also demonstrated SLAP's quick-turn abilities and high-resolution/wide-swath capabilities with 200m resolution across a 1500m swath from 2000 ft AGL. Additional flights were conducted as part of the GPM iPHEX campaign in May, 2014. 4. ConclusionThis paper presents flight data and imagery, as well as details of the radiometer and radar performance and calibration. The paper will also describe the mission performance achievable on the King Air and other platforms.

  17. Alpha-amylase Inhibition and Antioxidant Activity of Marine Green Algae and its Possible Role in Diabetes Management

    PubMed Central

    Unnikrishnan, P. S.; Suthindhiran, K.; Jayasri, M. A.


    Aim: In the continuing search for safe and efficient antidiabetic drug, marine algae become important source which provide several compounds of immense therapeutic potential. Alpha-amylase, alpha-glucosidase inhibitors, and antioxidant compounds are known to manage diabetes and have received much attention recently. In the present study, four green algae (Chaetomorpha aerea, Enteromorpha intestinalis, Chlorodesmis, and Cladophora rupestris) were chosen to evaluate alpha-amylase, alpha-glucosidase inhibitory, and antioxidant activity in vitro. Materials and Methods: The phytochemical constituents of all the extracts were qualitatively determined. Antidiabetic activity was evaluated by inhibitory potential of extracts against alpha-amylase and alpha-glucosidase by spectrophotometric assays. Antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl, hydrogen peroxide (H2O2), and nitric oxide scavenging assay. Gas chromatography-mass spectrometry (GC-MS) analysis was carried out to determine the major compound responsible for its antidiabetic action. Results: Among the various extracts screened, chloroform extract of C. aerea (IC50 − 408.9 μg/ml) and methanol extract of Chlorodesmis (IC50 − 147.6 μg/ml) showed effective inhibition against alpha-amylase. The extracts were also evaluated for alpha-glucosidase inhibition, and no observed activity was found. Methanol extract of C. rupestris showed notable free radical scavenging activity (IC50 – 666.3 μg/ml), followed by H2O2 (34%) and nitric oxide (49%). Further, chemical profiling by GC-MS revealed the presence of major bioactive compounds. Phenol, 2,4-bis (1,1-dimethylethyl) and z, z-6,28-heptatriactontadien-2-one were predominantly found in the methanol extract of C. rupestris and chloroform extract of C. aerea. Conclusion: Our results demonstrate that the selected algae exhibit notable alpha-amylase inhibition and antioxidant activity. Therefore, characterization of active compounds and its in vivo

  18. Monitoring airborne fungal spores in an experimental indoor environment to evaluate sampling methods and the effects of human activity on air sampling.

    PubMed Central

    Buttner, M P; Stetzenbach, L D


    Aerobiological monitoring was conducted in an experimental room to aid in the development of standardized sampling protocols for airborne microorganisms in the indoor environment. The objectives of this research were to evaluate the relative efficiencies of selected sampling methods for the retrieval of airborne fungal spores and to determine the effect of human activity on air sampling. Dry aerosols containing known concentrations of Penicillium chrysogenum spores were generated, and air samples were taken by using Andersen six-stage, Surface Air System, Burkard, and depositional samplers. The Andersen and Burkard samplers retrieved the highest numbers of spores compared with the measurement standard, an aerodynamic particle sizer located inside the room. Data from paired samplers demonstrated that the Andersen sampler had the highest levels of sensitivity and repeatability. With a carpet as the source of P. chrysogenum spores, the effects of human activity (walking or vacuuming near the sampling site) on air sampling were also examined. Air samples were taken under undisturbed conditions and after human activity in the room. Human activity resulted in retrieval of significantly higher concentrations of airborne spores. Surface sampling of the carpet revealed moderate to heavy contamination despite relatively low airborne counts. Therefore, in certain situations, air sampling without concomitant surface sampling may not adequately reflect the level of microbial contamination in indoor environments. PMID:8439150

  19. A role for 5alpha-reductase activity in the development of male homosexuality?


    Alias, A G


    Higher body hair with lower mesmorphism ratings were observed in Caucasian homosexual men compared with the general male population, reflecting elevated 5alpha-reductase (5alphaR) activity, and higher dihydrotestosterone-to-testosterone (DHT-to-T) ratio, in sharp contrast to 46,XY 5alphaR 2 deficiency subjects, who are often born with ambiguous, or female genitalia, but tend to grow up to be muscular, heterosexual men with very little body hair, or beard. One study also showed them scoring around dull normal IQs. A greater prevalence of liberal body hair growth in men with higher IQs and/or educational levels was also observed in several samples. The exceptions to this statistical trend are too unsettling, however. Nevertheless, the results of a number of published studies, including one showing higher DHT-to-T ratio in homosexual men, done with different objectives over a span of 80 years, together strongly support these findings. Furthermore, in an animal model, "cognitive-enhancing effects" of "5alpha-reduced androgen [metabolites]" were recently demonstrated. PMID:15677419

  20. Discovery of an Oxybenzylglycine Based Peroxisome Proliferator Activated Receptor Alpha Selective

    SciTech Connect

    Li, J.; Kennedy, L; Shi, Y; Tao, S; Ye, X; Chen, S; Wang, Y; Hernandez, A; Wang, W; et al.


    An 1,3-oxybenzylglycine based compound 2 (BMS-687453) was discovered to be a potent and selective peroxisome proliferator activated receptor (PPAR) {alpha} agonist, with an EC{sub 50} of 10 nM for human PPAR{alpha} and {approx}410-fold selectivity vs human PPAR{gamma} in PPAR-GAL4 transactivation assays. Similar potencies and selectivity were also observed in the full length receptor co-transfection assays. Compound 2 has negligible cross-reactivity against a panel of human nuclear hormone receptors including PPAR{delta}. Compound 2 demonstrated an excellent pharmacological and safety profile in preclinical studies and thus was chosen as a development candidate for the treatment of atherosclerosis and dyslipidemia. The X-ray cocrystal structures of the early lead compound 12 and compound 2 in complex with PPAR{alpha} ligand binding domain (LBD) were determined. The role of the crystal structure of compound 12 with PPAR{alpha} in the development of the SAR that ultimately resulted in the discovery of compound 2 is discussed.

  1. Structural Basis for Iloprost as a Dual Peroxisome Proliferator-activated Receptor [alpha/delta] Agonist

    SciTech Connect

    Jin, Lihua; Lin, Shengchen; Rong, Hui; Zheng, Songyang; Jin, Shikan; Wang, Rui; Li, Yong


    Iloprost is a prostacyclin analog that has been used to treat many vascular conditions. Peroxisome proliferator-activated receptors (PPARs) are ligand-regulated transcription factors with various important biological effects such as metabolic and cardiovascular physiology. Here, we report the crystal structures of the PPAR{alpha} ligand-binding domain and PPAR{delta} ligand-binding domain bound to iloprost, thus providing unambiguous evidence for the direct interaction between iloprost and PPARs and a structural basis for the recognition of PPAR{alpha}/{delta} by this prostacyclin analog. In addition to conserved contacts for all PPAR{alpha} ligands, iloprost also initiates several specific interactions with PPARs using its unique structural groups. Structural and functional studies of receptor-ligand interactions reveal strong functional correlations of the iloprost-PPAR{alpha}/{delta} interactions as well as the molecular basis of PPAR subtype selectivity toward iloprost ligand. As such, the structural mechanism may provide a more rational template for designing novel compounds targeting PPARs with more favorable pharmacologic impact based on existing iloprost drugs.

  2. Rational design of alpha-conotoxin analogues targeting alpha7 nicotinic acetylcholine receptors: improved antagonistic activity by incorporation of proline derivatives.


    Armishaw, Christopher; Jensen, Anders A; Balle, Thomas; Clark, Richard J; Harpsøe, Kasper; Skonberg, Christian; Liljefors, Tommy; Strømgaard, Kristian


    Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that belong to the superfamily of Cys loop receptors. Valuable insight into the orthosteric ligand binding to nAChRs in recent years has been obtained from the crystal structures of acetylcholine-binding proteins (AChBPs) that share significant sequence homology with the amino-terminal domains of the nAChRs. alpha-Conotoxins, which are isolated from the venom of carnivorous marine snails, selectively inhibit the signaling of neuronal nAChR subtypes. Co-crystal structures of alpha-conotoxins in complex with AChBP show that the side chain of a highly conserved proline residue in these toxins is oriented toward the hydrophobic binding pocket in the AChBP but does not have direct interactions with this pocket. In this study, we have designed and synthesized analogues of alpha-conotoxins ImI and PnIA[A10L], by introducing a range of substituents on the Pro(6) residue in these toxins to probe the importance of this residue for their binding to the nAChRs. Pharmacological characterization of the toxin analogues at the alpha(7) nAChR shows that although polar and charged groups on Pro(6) result in analogues with significantly reduced antagonistic activities, analogues with aromatic and hydrophobic substituents in the Pro(6) position exhibit moderate activity at the receptor. Interestingly, introduction of a 5-(R)-phenyl substituent at Pro(6) in alpha-conotoxin ImI gives rise to a conotoxin analogue with a significantly higher binding affinity and antagonistic activity at the alpha(7) nAChR than those exhibited by the native conotoxin. PMID:19131337

  3. Dissociation of TNF-alpha cytotoxic and proinflammatory activities by p55 receptor- and p75 receptor-selective TNF-alpha mutants.

    PubMed Central

    Barbara, J A; Smith, W B; Gamble, J R; Van Ostade, X; Vandenabeele, P; Tavernier, J; Fiers, W; Vadas, M A; Lopez, A F


    Human tumour necrosis factor alpha (TNF-alpha) is a pleiotropic cytokine capable of killing mammalian tumour cells in vitro and in vivo, and of enhancing the proinflammatory activity of leucocytes and endothelium, the latter effects limiting its usage as an antitumour agent in humans. Using TNF-alpha mutants with a selective capacity to bind to the TNF p55 receptor (TNFR55) or to the p75 receptor (TNFR75) we show here that these two major activities of TNF-alpha can be dissociated. The TNFR55-selective mutants (R32W, E146K and R32W-S86T) which bind poorly to TNFR75 displayed similar potency to wild-type TNF in causing cytotoxicity of a human laryngeal carcinoma-derived cell line (HEp-2) and cytostasis in a human leukaemic cell line (U937). However, these TNFR55-selective mutants exhibited lower proinflammatory activity than wild-type TNF. Specifically, TNF-alpha's priming of human neutrophils for superoxide production and antibody-dependent cell-mediated cytotoxicity, platelet-activating factor synthesis and adhesion to endothelium were reduced by up to 170-fold. Activation of human endothelial cell functions represented by human umbilical venular endothelial cell (HUVEC) adhesiveness for neutrophils, E-selectin expression, neutrophil transmigration and IL-8 secretion were also reduced by up to 280-fold. On the other hand, D143F, a TNFR75-selective mutant tested either alone or in combination with TNFR55-selective mutants, did not stimulate these activities despite being able to cause cytokine production in TNFR75-transfected PC60 cells.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7509279

  4. alpha 2-adrenoreceptors profile modulation. 2. Biphenyline analogues as tools for selective activation of the alpha 2C-subtype.


    Gentili, Francesco; Ghelfi, Francesca; Giannella, Mario; Piergentili, Alessandro; Pigini, Maria; Quaglia, Wilma; Vesprini, Cristian; Crassous, Pierre-Antoine; Paris, Hervé; Carrieri, Antonio


    A series of derivatives structurally related to biphenyline (3) was designed with the aim to modulate selectivity toward the alpha(2)-AR subtypes. The results obtained demonstrated that the presence of a correctly oriented function with positive electronic effect (+sigma) in portion X of the ligands is an important factor for significant alpha(2C)-subtype selectivity (imidazolines 5, 13, 16, and 19). Homology modeling and docking studies support experimental data and highlight the crucial role for the hydrogen bond between the pyridine nitrogen in position 3 of 5 and the NH-indole ring of Trp6.48, which is favorably oriented in the alpha(2C)-subtype, only. PMID:15566287

  5. Characterization of Tank 48H Samples for Alpha Activity and Actinide Isotopics

    SciTech Connect

    Hobbs, D.T.; Coleman, C.J.; Hay, M.S.


    This document reports the total alpha activity and actinide isotopic results for samples taken from Tank 48H prior to the addition of sodium tetraphenylborate and MST in Batch {number_sign}1 of the ITP process. This information used to determine the quantity of MST for Batch {number_sign}1 of the ITP process and the total actinide content in the tank for dose calculations.

  6. 5-alpha reductase inhibitors in patients on active surveillance: do the benefits outweigh the risk?


    Al Edwan, Ghazi; Fleshner, Neil


    Prostate cancer (PCa) is a slow, progressive disease. Prostate specific antigen testing, screening, and aggressive case identification has made PCa the most frequently diagnosed cancer. Concerns regarding overdiagnosis and overtreatment flourish on a large scale. In order to avoid overtreatment for those in whom therapeutic intervention is not required, active surveillance for eligible patients with the use of 5-alpha reductase can be considered a safe and a promising approach to delay the progression of the disease with minimal side effects. PMID:23579402

  7. Synthesis and evaluation of antiinflammatory activities of a series of corticosteroid 17 alpha-esters containing a functional group.


    Ueno, H; Maruyama, A; Miyake, M; Nakao, E; Nakao, K; Umezu, K; Nitta, I


    A series of 21-desoxy-21-chlorocorticosteroids that contain a functionalized ester group at 17 alpha has been prepared and examined to separate their systemic activity from topical antiinflammatory activity. Introduction of the functionalized ester group at 17 alpha was carried out by an acid-catalyzed formation of cyclic ortho esters with 17 alpha,21-hydroxyl groups of corticosteroids and subsequent acid-catalyzed hydrolysis. As for the functional group, chloro, methoxy, acetoxy, cyano, cyclopropyl, or alkoxycarbonyl group was introduced at the terminal carbon atom of the 17 alpha-alkanoate group. The topical antiinflammatory activity and systemic activity of these compounds were examined and found to be significantly dependent on the functionalities in the 17 alpha-esters. Among these derivatives, a series of 17 alpha-(alkoxycarbonyl)alkanoates (17 alpha-OCO(CH2)nCOOR) showed an excellent separation of the systemic activity from topical activity. The effects of the number of methylene groups (n) and of the alkyl groups of the ester (R) on either topical or systemic activity of the corticosteroid derivatives were also investigated. PMID:1875343

  8. Fatty Acid Amide Hydrolase (FAAH) Inhibition Enhances Memory Acquisition through Activation of PPAR-alpha Nuclear Receptors

    ERIC Educational Resources Information Center

    Mazzola, Carmen; Medalie, Julie; Scherma, Maria; Panlilio, Leigh V.; Solinas, Marcello; Tanda, Gianluigi; Drago, Filippo; Cadet, Jean Lud; Goldberg, Steven R.; Yasar, Sevil


    Inhibitors of fatty acid amide hydrolase (FAAH) increase endogenous levels of anandamide (a cannabinoid CB[subscript 1]-receptor ligand) and oleoylethanolamide and palmitoylethanolamide (OEA and PEA, ligands for alpha-type peroxisome proliferator-activated nuclear receptors, PPAR-alpha) when and where they are naturally released in the brain.…

  9. New evidence of similarity between human and plant steroid metabolism: 5alpha-reductase activity in Solanum malacoxylon.


    Rosati, Fabiana; Danza, Giovanna; Guarna, Antonio; Cini, Nicoletta; Racchi, Milvia Luisa; Serio, Mario


    The physiological role of steroid hormones in humans is well known, and the metabolic pathway and mechanisms of action are almost completely elucidated. The role of plant steroid hormones, brassinosteroids, is less known, but an increasing amount of data on brassinosteroid biosynthesis is showing unexpected similarities between human and plant steroid metabolic pathways. Here we focus our attention on the enzyme 5alpha-reductase (5alphaR) for which a plant ortholog of the mammalian system, DET2, was recently described in Arabidopsis thaliana. We demonstrate that campestenone, the natural substrate of DET2, is reduced to 5alpha-campestanone by both human 5alphaR isozymes but with different affinities. Solanum malacoxylon, which is a calcinogenic plant very active in the biosynthesis of vitamin D-like molecules and sterols, was used to study 5alphaR activity. Leaves and calli were chosen as examples of differentiated and undifferentiated tissues, respectively. Two separate 5alphaR activities were found in calli and leaves of Solanum using campestenone as substrate. The use of progesterone allowed the detection of both activities in calli. Support for the existence of two 5alphaR isozymes in S. malacoxylon was provided by the differential actions of inhibitors of the human 5alphaR in calli and leaves. The evidence for the presence of two isozymes in different plant tissues extends the analogies between plant and mammalian steroid metabolic pathways. PMID:12488348

  10. Deficiency in Na,K-ATPase alpha isoform genes alters spatial learning, motor activity, and anxiety in mice.


    Moseley, Amy E; Williams, Michael T; Schaefer, Tori L; Bohanan, Cynthia S; Neumann, Jon C; Behbehani, Michael M; Vorhees, Charles V; Lingrel, Jerry B


    Several disorders have been associated with mutations in Na,K-ATPase alpha isoforms (rapid-onset dystonia parkinsonism, familial hemiplegic migraine type-2), as well as reduction in Na,K-ATPase content (depression and Alzheimer's disease), thereby raising the issue of whether haploinsufficiency or altered enzymatic function contribute to disease etiology. Three isoforms are expressed in the brain: the alpha1 isoform is found in many cell types, the alpha2 isoform is predominantly expressed in astrocytes, and the alpha3 isoform is exclusively expressed in neurons. Here we show that mice heterozygous for the alpha2 isoform display increased anxiety-related behavior, reduced locomotor activity, and impaired spatial learning in the Morris water maze. Mice heterozygous for the alpha3 isoform displayed spatial learning and memory deficits unrelated to differences in cued learning in the Morris maze, increased locomotor activity, an increased locomotor response to methamphetamine, and a 40% reduction in hippocampal NMDA receptor expression. In contrast, heterozygous alpha1 isoform mice showed increased locomotor response to methamphetamine and increased basal and stimulated corticosterone in plasma. The learning and memory deficits observed in the alpha2 and alpha3 heterozygous mice reveal the Na,K-ATPase to be an important factor in the functioning of pathways associated with spatial learning. The neurobehavioral changes seen in heterozygous mice suggest that these mouse models may be useful in future investigations of the associated human CNS disorders. PMID:17234593

  11. Correlation between phosphatidylinositol labeling and contraction in rabbit aorta: effect of alpha-1 adrenergic activation

    SciTech Connect

    Villalobos-Molina, R.; Uc, M.; Hong, E.; Garcia-Sainz, J.A.


    Activation of rabbit aortic strips with alpha adrenergic agonists increased the labeling (with (/sup 32/P)Pi) of phosphatidylinositol (PI) and phosphatidic acid and contracted the vascular preparations in dose-related fashion. Epinephrine, norepinephrine and methoxamine produced maximal effects, whereas clonidine behaved as partial agonist and B-HT 933 (2-amino-6-ethyl-4,5,7,8-tetrahydro-6H-oxazole-(5,4-d) azepin dihydrochloride) was almost without activity in the two experimental models used. Phenylephrine was a full agonist in producing contraction, but failed to elicit the maximal increase in PI labeling. The EC50 values to produce contraction of aortic strips were lower for all agonists than those required to increase the incorporation of radioactive phosphate into PI, but there was a good correlation between the two sets of data. The increased PI labeling and contraction of aortic strips induced by epinephrine were antagonized by prazosin and yohimbine in dose-related fashion, but the first alpha blocker was about three orders of magnitude more potent than the second in antagonizing the two effects. The present results indicate that both stimulation of PI labeling and contraction are mediated through activation of alpha-1 adrenoceptors in rabbit aorta.

  12. Sight restoration after congenital blindness does not reinstate alpha oscillatory activity in humans.


    Bottari, Davide; Troje, Nikolaus F; Ley, Pia; Hense, Marlene; Kekunnaya, Ramesh; Röder, Brigitte


    Functional brain development is characterized by sensitive periods during which experience must be available to allow for the full development of neural circuits and associated behavior. Yet, only few neural markers of sensitive period plasticity in humans are known. Here we employed electroencephalographic recordings in a unique sample of twelve humans who had been blind from birth and regained sight through cataract surgery between four months and 16 years of age. Two additional control groups were tested: a group of visually impaired individuals without a history of total congenital blindness and a group of typically sighted individuals. The EEG was recorded while participants performed a visual discrimination task involving intact and scrambled biological motion stimuli. Posterior alpha and theta oscillations were evaluated. The three groups showed indistinguishable behavioral performance and in all groups evoked theta activity varied with biological motion processing. By contrast, alpha oscillatory activity was significantly reduced only in individuals with a history of congenital cataracts. These data document on the one hand brain mechanisms of functional recovery (related to theta oscillations) and on the other hand, for the first time, a sensitive period for the development of alpha oscillatory activity in humans. PMID:27080158

  13. Sight restoration after congenital blindness does not reinstate alpha oscillatory activity in humans

    PubMed Central

    Bottari, Davide; Troje, Nikolaus F.; Ley, Pia; Hense, Marlene; Kekunnaya, Ramesh; Röder, Brigitte


    Functional brain development is characterized by sensitive periods during which experience must be available to allow for the full development of neural circuits and associated behavior. Yet, only few neural markers of sensitive period plasticity in humans are known. Here we employed electroencephalographic recordings in a unique sample of twelve humans who had been blind from birth and regained sight through cataract surgery between four months and 16 years of age. Two additional control groups were tested: a group of visually impaired individuals without a history of total congenital blindness and a group of typically sighted individuals. The EEG was recorded while participants performed a visual discrimination task involving intact and scrambled biological motion stimuli. Posterior alpha and theta oscillations were evaluated. The three groups showed indistinguishable behavioral performance and in all groups evoked theta activity varied with biological motion processing. By contrast, alpha oscillatory activity was significantly reduced only in individuals with a history of congenital cataracts. These data document on the one hand brain mechanisms of functional recovery (related to theta oscillations) and on the other hand, for the first time, a sensitive period for the development of alpha oscillatory activity in humans. PMID:27080158

  14. Airborne laser

    NASA Astrophysics Data System (ADS)

    Lamberson, Steven E.


    The US Air Force Airborne Laser (ABL) is an airborne, megawatt-class laser system with a state-of-the-art atmospheric compensation system to destroy enemy ballistic missiles at long ranges. This system will provide both deterrence and defense against the use of such weapons during conflicts. This paper provides an overview of the ABL weapon system including: the notional operational concept, the development approach and schedule, the overall aircraft configuration, the technologies being incorporated in the ABL, and the risk reduction approach being utilized to ensure program success.

  15. The core-specific lysosomal alpha(1-6)-mannosidase activity depends on aspartamidohydrolase activity.

    PubMed Central

    Haeuw, J F; Grard, T; Alonso, C; Strecker, G; Michalski, J C


    The substrate specificity of the core-specific rat liver lysosomal alpha(1-6)-mannosidase was investigated using mannosylated oligosaccharides and glycoasparagines. Hydrolysis of Man(alpha 1-6) linkage hydrolysis was demonstrated to follow the action of endoglycosidases, namely aspartyl-N-acetyl-beta-D-glucosaminidase and endo-N-acetyl-beta-D-glucosaminidase. The results are discussed with respect to the nature of the carbohydrate materials stored in the tissues and excreted in the urine from patients suffering from aspartylglucosaminuria and fucosidosis. Images Figure 1 Figure 2 PMID:8110182

  16. Destruction of problematic airborne contaminants by hydrogen reduction using a Catalytically Active, Regenerable Sorbent (CARS)

    NASA Technical Reports Server (NTRS)

    Thompson, John O.; Akse, James R.


    Thermally regenerable sorbent beds were demonstrated to be a highly efficient means for removal of toxic airborne trace organic contaminants aboard spacecraft. The utilization of the intrinsic weight savings available through this technology was not realized since many of the contaminants desorbed during thermal regeneration are poisons to the catalytic oxidizer or form highly toxic oxidation by-products in the Trace Contaminant Control System (TCCS). Included in this class of compounds are nitrogen, sulfur, silicon, and halogen containing organics. The catalytic reduction of these problematic contaminants using hydrogen at low temperatures (200-300 C) offers an attractive route for their destruction since the by-products of such reactions, hydrocarbons and inorganic gases, are easily removed by existing technology. In addition, the catalytic oxidizer can be operated more efficiently due to the absence of potential poisons, and any posttreatment beds can be reduced in size. The incorporation of the catalyst within the sorbent bed further improves the system's efficiency. The demonstration of this technology provides the basis for an efficient regenerable TCCS for future NASA missions and can be used in more conventional settings to efficiently remove environmental pollutants.

  17. Interleukin 10 inhibits macrophage microbicidal activity by blocking the endogenous production of tumor necrosis factor alpha required as a costimulatory factor for interferon gamma-induced activation.

    PubMed Central

    Oswald, I P; Wynn, T A; Sher, A; James, S L


    Interleukin 10 (IL-10) inhibits interferon gamma-induced macrophage activation for cytotoxicity against larvae of the human parasite Schistosoma mansoni by suppressing production of the toxic effector molecule nitric oxide (NO). In this study, the mechanism of IL-10 action was identified as inhibition of endogenous tumor necrosis factor alpha (TNF-alpha) production by interferon gamma-activated macrophages. TNF-alpha appears to serve as a cofactor for interferon gamma-mediated activation, since both schistosomulum killing and NO production were inhibited by anti-TNF-alpha antibody, whereas TNF-alpha alone was unable to stimulate these macrophage functions. IL-10 blocked TNF-alpha production by interferon gamma-treated macrophages at the levels of both protein and mRNA synthesis. Addition of exogenous TNF-alpha reversed IL-10-mediated suppression of macrophage cytotoxic activity as well as NO production. Likewise, addition of a macrophage-triggering agent (bacterial lipopolysaccharide or muramyl dipeptide), which induced the production of TNF-alpha, also reversed the suppressive effect of IL-10 on cytotoxic function. In contrast to IL-10, two other cytokines, IL-4 and transforming growth factor beta, which also inhibit macrophage activation for schistosomulum killing and NO production, did not substantially suppress endogenous TNF-alpha production. These results, therefore, describe a separate pathway by which macrophage microbicidal function is inhibited by the down-regulatory cytokine IL-10. Images PMID:1528880

  18. PITBUL: a physics-based modeling package for imaging and tracking of airborne targets for HEL applications including active illumination

    NASA Astrophysics Data System (ADS)

    Van Zandt, Noah R.; McCrae, Jack E.; Fiorino, Steven T.


    Aimpoint acquisition and maintenance is critical to high energy laser (HEL) system performance. This study demonstrates the development by the AFIT/CDE of a physics-based modeling package, PITBUL, for tracking airborne targets for HEL applications, including atmospheric and sensor effects and active illumination, which is a focus of this work. High-resolution simulated imagery of the 3D airborne target in-flight as seen from the laser position is generated using the HELSEEM model, and includes solar illumination, laser illumination, and thermal emission. Both CW and pulsed laser illumination are modeled, including the effects of illuminator scintillation, atmospheric backscatter, and speckle, which are treated at a first-principles level. Realistic vertical profiles of molecular and aerosol absorption and scattering, as well as optical turbulence, are generated using AFIT/CDE's Laser Environmental Effects Definition and Reference (LEEDR) model. The spatially and temporally varying effects of turbulence are calculated and applied via a fast-running wave optical method known as light tunneling. Sensor effects, for example blur, sampling, read-out noise, and random photon arrival, are applied to the imagery. Track algorithms, including centroid and Fitts correlation, as a part of a closed loop tracker are applied to the degraded imagery and scored, to provide an estimate of overall system performance. To gauge performance of a laser system against a UAV target, tracking results are presented as a function of signal to noise ratio. Additionally, validation efforts to date involving comparisons between simulated and experimental tracking of UAVs are presented.

  19. Regulation of the human SLC25A20 expression by peroxisome proliferator-activated receptor alpha in human hepatoblastoma cells

    SciTech Connect

    Tachibana, Keisuke; Takeuchi, Kentaro; Inada, Hirohiko; Yamasaki, Daisuke; The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 ; Ishimoto, Kenji; Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 ; Tanaka, Toshiya; Hamakubo, Takao; Sakai, Juro; Kodama, Tatsuhiko; Doi, Takefumi; The Center for Advanced Medical Engineering and Informatics, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871; Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871


    Solute carrier family 25, member 20 (SLC25A20) is a key molecule that transfers acylcarnitine esters in exchange for free carnitine across the mitochondrial membrane in the mitochondrial {beta}-oxidation. The peroxisome proliferator-activated receptor alpha (PPAR{alpha}) is a ligand-activated transcription factor that plays an important role in the regulation of {beta}-oxidation. We previously established tetracycline-regulated human cell line that can be induced to express PPAR{alpha} and found that PPAR{alpha} induces the SLC25A20 expression. In this study, we analyzed the promoter region of the human slc25a20 gene and showed that PPAR{alpha} regulates the expression of human SLC25A20 via the peroxisome proliferator responsive element.

  20. GATA-1 modulates the chromatin structure and activity of the chicken alpha-globin 3' enhancer.


    Escamilla-Del-Arenal, Martín; Recillas-Targa, Félix


    Long-distance regulatory elements and local chromatin structure are critical for proper regulation of gene expression. Here we characterize the chromatin conformation of the chicken alpha-globin silencer-enhancer elements located 3' of the domain. We found a characteristic and erythrocyte-specific structure between the previously defined silencer and the enhancer, defined by two nuclease hypersensitive sites, which appear when the enhancer is active during erythroid differentiation. Fine mapping of these sites demonstrates the absence of a positioned nucleosome and the association of GATA-1. Functional analyses of episomal vectors, as well as stably integrated constructs, revealed that GATA-1 plays a major role in defining both the chromatin structure and the enhancer activity. We detected a progressive enrichment of histone acetylation on critical enhancer nuclear factor binding sites, in correlation with the formation of an apparent nucleosome-free region. On the basis of these results, we propose that the local chromatin structure of the chicken alpha-globin enhancer plays a central role in its capacity to differentially regulate alpha-globin gene expression during erythroid differentiation and development. PMID:17984219

  1. Effect of salivary gland adenocarcinoma cell-derived alpha-N-acetylgalactosaminidase on the bioactivity of macrophage activating factor.


    Matsuura, Takashi; Uematsu, Takashi; Yamaoka, Minoru; Furusawa, Kiyofumi


    The aim of this study was to clarify the effects of alpha-N-acetylgalactosaminidase (alpha-NaGalase) produced by human salivary gland adenocarcinoma (SGA) cells on the bioactivity of macrophage-activating factor (GcMAF). High exo-alpha-NaGalase activity was detected in the SGA cell line HSG. HSG alpha-NaGalase had both exo- and endo-enzyme activities, cleaving the Gal-GalNAc and GalNAc residues linked to Thr/Ser but not releasing the [NeuAc2-6]GalNac residue. Furthermore, GcMAF enzymatically prepared from the Gc protein enhanced the superoxide-generation capacity and phagocytic activity of monocytes/macrophages. However, GcMAF treated with purified alpha-NaGalase did not exhibit these effects. Thus, HSG possesses the capacity to produce larger quantities of alpha-NaGalase, which inactivates GcMAF produced from Gc protein, resulting in reduced phagocytic activity and superoxide-generation capacity of monocytes/macrophages. The present data strongly suggest that HSG alpha-NaGalase acts as an immunodeficiency factor in cancer patients. PMID:14767536

  2. Structural and Biochemical Basis for the Binding Selectivity of Peroxisome Proliferator-activated Receptor [gamma] to PGC-1[alpha

    SciTech Connect

    Li, Yong; Kovach, Amanda; Suino-Powell, Kelly; Martynowski, Dariusz; Xu, H. Eric


    The functional interaction between the peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) and its coactivator PGC-1{alpha} is crucial for the normal physiology of PPAR{gamma} and its pharmacological response to antidiabetic treatment with rosiglitazone. Here we report the crystal structure of the PPAR{gamma} ligand-binding domain bound to rosiglitazone and to a large PGC-1{alpha} fragment that contains two LXXLL-related motifs. The structure reveals critical contacts mediated through the first LXXLL motif of PGC-1{alpha} and the PPAR{gamma} coactivator binding site. Through a combination of biochemical and structural studies, we demonstrate that the first LXXLL motif is the most potent among all nuclear receptor coactivator motifs tested, and only this motif of the two LXXLL-related motifs in PGC-1{alpha} is capable of binding to PPAR{gamma}. Our studies reveal that the strong interaction of PGC-1{alpha} and PPAR{gamma} is mediated through both hydrophobic and specific polar interactions. Mutations within the context of the full-length PGC-1{alpha} indicate that the first PGC-1{alpha} motif is necessary and sufficient for PGC-1{alpha} to coactivate PPAR{gamma} in the presence or absence of rosiglitazone. These results provide a molecular basis for specific recruitment and functional interplay between PPAR{gamma} and PGC-1{alpha} in glucose homeostasis and adipocyte differentiation.

  3. Alpha-D-galactosylation of surface fucoglycoconjugate(s) upon stimulation/activation of murine peritoneal macrophages.


    Petryniak, J


    Murine resident macrophages express, on their surface, carbohydrate epitopes which undergo changes during their stimulation/activation as monitored by binding of 125I labelled Evonymus europaea and Griffonia simplicifolia I-B4 lectins. Treatment of the stimulated macrophages with coffee bean alpha-galactosidase abolished binding of the GS I-B4 isolectin and changed the binding pattern of the Evonymus lectin. The affinity (Ka) of Evonymus lectin for alpha-galactosidase-treated macrophages decreased approximately 23-fold, from 1.25 x 10(8) M-1 to 5.5 x 10(6) M-1. Subsequent digestion of alpha-galactosidase-treated macrophages with alpha-L-fucosidase from Trichomonas foetus, further reduced binding of Evonymus lectin. Resident macrophages showed the same pattern of Evonymus lectin binding, with the same affinity, as alpha-galactosidase-treated, stimulated macrophages. These results, together with a consideration of the carbohydrate binding specificity of the Evonymus lectin which, in the absence of alpha-D-galactosyl groups, requires alpha-L-fucosyl groups for binding, indicate the presence, on resident macrophages, of glycoconjugates with terminal alpha-L-fucosyl residues. It is also concluded that during macrophage stimulation/activation alpha-D-galactosyl residues are added to this glycoconjugate and that they form part of the receptor for Evonymus lectin. The same glycoconjugate(s) is/are also expressed on the activated macrophage IC-21 cell line which exhibits the same characteristics as that of stimulated peritoneal macrophages, i.e., it contains alpha-D-galactosyl end groups and is resistant to the action of trypsin. Both lectins were also specifically bound to Corynaebacterium parvum activated macrophages. PMID:1344714

  4. Centaurin-alpha 1, an ADP-ribosylation factor 6 GTPase activating protein, inhibits beta 2-adrenoceptor internalization.


    Lawrence, Joanna; Mundell, Stuart J; Yun, Hongruo; Kelly, Eamonn; Venkateswarlu, Kanamarlapudi


    The small GTP-binding protein ADP ribosylation factor 6 (ARF6) has recently been implicated in the internalization of G protein-coupled receptors (GPCRs), although its precise molecular mechanism in this process remains unclear. We have recently identified centaurin alpha(1) as a GTPase activating protein (GAP) for ARF6. In the current study, we characterized the effects of centaurin alpha(1) on the agonist-induced internalization of the beta(2)-adrenoceptor transiently expressed in human embryonic kidney (HEK) 293 cells. Using an enzyme-linked immunosorbent assay as well as confocal imaging of cells, we found that expression of centaurin alpha(1) strongly inhibited the isoproterenol-induced internalization of beta(2)-adrenoceptor. On the other hand, expression of functionally inactive versions of centaurin alpha(1), including an R49C mutant, which has no catalytic activity, and a double pleckstrin homology (PH) mutant (DM; R148C/R273C), which has mutations in both the PH domains of centaurin alpha(1), rendering it unable to translocate to the cell membrane, were unable to inhibit beta(2)-adrenoceptor internalization. In addition, a constitutively active version of ARF6, ARF6Q67L, reversed the ability of centaurin alpha(1) to inhibit beta(2)-adrenoceptor internalization. Finally, expression of centaurin alpha(1) also inhibited the agonist-induced internalization of beta(2)-adrenoceptor endogenously expressed in HEK 293 cells, whereas the R49C and DM mutant versions of centaurin alpha(1) had no effect. Together, these data indicate that by acting as an ARF6 GAP, centaurin alpha(1) is able to switch off ARF6 and so inhibit its ability to mediate beta(2)-adrenoceptor internalization. Thus, ARF6 GAPs, such as centaurin alpha(1), are likely to play a crucial role in GPCR trafficking by modulating the activity of ARF6. PMID:15778454

  5. Detailed correlation of type III radio bursts with H alpha activity. I - Active region of 22 May 1970.

    NASA Technical Reports Server (NTRS)

    Kuiper, T. B. H.; Pasachoff, J. M.


    Comparison of observations of type III impulsive radio bursts made at the Clark Lake Radio Observatory with high-spatial-resolution cinematographic observations taken at the Big Bear Solar Observatory. Use of the log-periodic radio interferometer makes it possible to localize the radio emission uniquely. This study concentrates on the particularly active region close to the limb on May 22, 1970. Sixteen of the 17 groups were associated with some H alpha activity, 11 of them with the start of such activity.

  6. Active site titration of bovine beta-trypsin by N alpha-(N,N-dimethylcarbamoyl)-alpha-aza-lysine p-nitrophenyl ester: kinetic and crystallographic analysis.


    Sartori, P; Djinovic Carugo, K; Ferraccioli, R; Balliano, G; Milla, P; Ascenzi, P; Bolognesi, M


    Kinetics of bovine beta-trypsin (trypsin) with the N alpha-(N,N-dimethylcarbamoyl)-alpha-aza-lysine p-nitrophenyl ester (Dmc-azaLys-ONp) was obtained at pH 6.2 and 21.0 degrees C. Dmc-azaLys-ONp shows the characteristics of an optimal active site titrant in that it (i) gives titrations in a short time, (ii) is a stable and soluble compound with a stoichiometric reaction that is easily and directly detectable, and (iii) allows titrations over a wide range of enzyme concentration. Moreover, the three-dimensional structure of the trypsin.N alpha-(N,N-dimet hylcarbamoyl)-alpha-aza-lysine acyl.enzyme adduct has been solved by X-ray crystallography at 2.0 A resolution (R = 0.145). The Dmc-azaLys moiety of the active site titrant is sited in the serine proteinase reaction center, and is covalently linked to the OG atom of the Ser195 catalytic residue. PMID:7821429

  7. Effects of particle size and velocity on burial depth of airborne particles in glass fiber filters

    SciTech Connect

    Higby, D.P.


    Air sampling for particulate radioactive material involves collecting airborne particles on a filter and then determining the amount of radioactivity collected per unit volume of air drawn through the filter. The amount of radioactivity collected is frequently determined by directly measuring the radiation emitted from the particles collected on the filter. Counting losses caused by the particle becoming buried in the filter matrix may cause concentrations of airborne particulate radioactive materials to be underestimated by as much as 50%. Furthermore, the dose calculation for inhaled radionuclides will also be affected. The present study was designed to evaluate the extent to which particle size and sampling velocity influence burial depth in glass-fiber filters. Aerosols of high-fired /sup 239/PuO/sub 2/ were collected at various sampling velocities on glass-fiber filters. The fraction of alpha counts lost due to burial was determined as the ratio of activity detected by direct alpha count to the quantity determined by photon spectrometry. The results show that burial of airborne particles collected on glass-fiber filters appears to be a weak function of sampling velocity and particle size. Counting losses ranged from 0 to 25%. A correction that assumes losses of 10 to 15% would ensure that the concentration of airborne alpha-emitting radionuclides would not be underestimated when glass-fiber filters are used. 32 references, 21 figures, 11 tables.

  8. Airborne concentrations of peanut protein.


    Johnson, Rodney M; Barnes, Charles S


    Food allergy to peanut is a significant health problem, and there are reported allergic reactions to peanuts despite not eating or having physical contact with peanuts. It is presumed that an allergic reaction may have occurred from inhalation of airborne peanut allergens. The purpose of this study was to detect the possible concentrations of airborne peanut proteins for various preparations and during specific activities. Separate Ara h 1 and Ara h 2 monoclonal enzyme-linked immunosorbent assays and a polyclonal sandwich enzyme immunoassay for peanuts were used to detect the amount of airborne peanut protein collected using a Spincon Omni 3000 air collector (Sceptor Industries, Inc., Kansas City, MO) under different peanut preparation methods and situations. Air samples were measured for multiple peanut preparations and scenarios. Detectable amounts of airborne peanut protein were measured using a whole peanut immunoassay when removing the shells of roasted peanut. No airborne peanut allergen (Ara h 1 or Ara h 2) or whole peanut protein above the LLD was measured in any of the other peanut preparation collections. Ara h 1, Ara h 2, and polyclonal peanut proteins were detected from water used to boil peanuts. Small amounts of airborne peanut protein were detected in the scenario of removing shells from roasted peanuts; however, Ara h 1 and Ara h 2 proteins were unable to be consistently detected. Although airborne peanut proteins were detected, the concentration of airborne peanut protein that is necessary to elicit a clinical allergic reaction is unknown. PMID:23406937

  9. Quantification of activity by alpha-camera imaging and small-scale dosimetry within ovarian carcinoma micrometastases treated with targeted alpha therapy.


    Chouin, N; Lindegren, S; Jensen, H; Albertsson, P; Bäck, T


    Targeted alpha therapy (TAT) a promising treatment for small, residual, and micrometastatic diseases has questionable efficacy against malignant lesions larger than the α-particle range, and likely requires favorable intratumoral activity distribution. Here, we characterized and quantified the activity distribution of an alpha-particle emitter radiolabelled antibody within >100-µm micrometastases in a murine ovarian carcinoma model. Nude mice bearing ovarian micrometastases were injected intra-peritoneally with 211At-MX35 (total injected activity 6 MBq, specific activity 650 MBq/mg). Animals were sacrificed at several time points, and peritoneal samples were excised and prepared for alpha-camera imaging. Spatial and temporal activity distributions within micrometastases were derived and used for small-scale dosimetry. We observed two activity distribution patterns: uniform distribution and high stable uptake (>100% IA/g at all time points) in micrometastases with no visible stromal compartment, and radial distribution (high activity on the edge and poor uptake in the core) in tumor cell lobules surrounded by fibroblasts. Activity distributions over time were characterized by a peak (140% IA/g at 4 h) in the outer tumor layer and a sharp drop beyond a depth of 50 µm. Small-scale dosimetry was performed on a multi-cellular micrometastasis model, using time-integrated activities derived from the experimental data. With injected activity of 400 kBq, tumors exhibiting uniform activity distribution received <25 Gy (EUD=13 Gy), whereas tumors presenting radial activity distribution received mean absorbed doses of <8 Gy (EUD=5 Gy). These results provide new insight into important aspects of TAT, and may explain why micrometastases >100 µm might not be effectively treated by the examined regimen. PMID:23358400

  10. Integrin alpha1beta1 regulates epidermal growth factor receptor activation by controlling peroxisome proliferator-activated receptor gamma-dependent caveolin-1 expression.


    Chen, Xiwu; Whiting, Carrie; Borza, Corina; Hu, Wen; Mont, Stacey; Bulus, Nada; Zhang, Ming-Zhi; Harris, Raymond C; Zent, Roy; Pozzi, Ambra


    Integrin alpha1beta1 negatively regulates the generation of profibrotic reactive oxygen species (ROS) by inhibiting epidermal growth factor receptor (EGFR) activation; however, the mechanism by which it does this is unknown. In this study, we show that caveolin-1 (Cav-1), a scaffolding protein that binds integrins and controls growth factor receptor signaling, participates in integrin alpha1beta1-mediated EGFR activation. Integrin alpha1-null mesangial cells (MCs) have reduced Cav-1 levels, and reexpression of the integrin alpha1 subunit increases Cav-1 levels, decreases EGFR activation, and reduces ROS production. Downregulation of Cav-1 in wild-type MCs increases EGFR phosphorylation and ROS synthesis, while overexpression of Cav-1 in the integrin alpha1-null MCs decreases EGFR-mediated ROS production. We further show that integrin alpha1-null MCs have increased levels of activated extracellular signal-regulated kinase (ERK), which leads to reduced activation of peroxisome proliferator-activated receptor gamma (PPARgamma), a transcription factor that positively regulates Cav-1 expression. Moreover, activation of PPARgamma or inhibition of ERK increases Cav-1 levels in the integrin alpha1-null MCs. Finally, we show that glomeruli of integrin alpha1-null mice have reduced levels of Cav-1 and activated PPARgamma but increased levels of phosphorylated EGFR both at baseline and following injury. Thus, integrin alpha1beta1 negatively regulates EGFR activation by positively controlling Cav-1 levels, and the ERK/PPARgamma axis plays a key role in regulating integrin alpha1beta1-dependent Cav-1 expression and consequent EGFR-mediated ROS production. PMID:20368353

  11. Identification of a mutation affecting an alanine-alpha-ketoisovalerate transaminase activity in Escherichia coli K-12.


    Falkinham, J O


    A mutation affecting alanine-alpha-ketoisovalerate transaminase activity has been shown to be cotransducible with ilv gene cluster. The transaminase deficiency results in conditional isoleucine auxotrophy in the presence of alanine. PMID:396446

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


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


    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

  13. Alpha-amylase inhibitory activity and phytochemical study of Zhumeria majdae Rech. f. and Wendelbo

    PubMed Central

    Mirshafie, Behnaz; Mokhber-Dezfouli, Najmeh; Manayi, Azadeh; Saeidnia, Soodabeh; Ajani, Yousef; Gohari, Ahmad Reza


    Background: Zhumeria majdae (Lamiaceae) is an endemic species growing in the South parts of Iran especially Hormozgan province. The plant is so-called Mohrekhosh locally and widely used for medicinal purposes including stomachache and dysmenorrhea. Objective: In order to separation and identification of the main flavonoid glycosides of the plant (aerial parts including leaves, stems, flowers, and fruits were used) and evaluation of its alpha-amylase inhibitory (AAI) activity, methanolic extract was prepared and fractionated to botanolic portion. Materials and Methods: Isolation of the main compounds of the butanol extract of the plant have been performed using different column chromatography methods such as high-performance liquid chromatography (C18 column) and Sephadex LH-20 as well. The isolated compounds were identified by Hydrogen-1 nuclear magnetic resonance and Carbon-13 nuclear magnetic resonance spectra and comparison with those reported in previous literature. Moreover, inhibitory activity of the butanolic extract of the plant against alpha-amylase enzyme was examined in different concentrations (15–30 mg/mL), where acarbose used as a positive control. Results: Three flavonoid glycosides: Linarin (1), hispidulin-7-O-(4-O-acetyl-rutinoside) (2), hispidulin-7-O-rutinoside (3) were successfully identified in the extract. The activity of alpha amylase enzyme was dose-dependently suppressed by the butanol extract. The extract exhibited the highest inhibition at 30 mg/mL toward enzyme (77.9 ± 2.1%), while acarbose inhibited the enzyme at 20 mg/mL by 73.9 ± 1.9%. The inhibitory concentrations of 50% for the extract and acarbose were calculated at 24.5 ± 2.1 and 6.6 ± 3.1 mg/mL, respectively. Conclusion: Z. majdae contains glycosylated flavones and could be a good candidate for anti-diabetic evaluations in animal and clinical trials due to possessing AAI activity. PMID:26692743

  14. A comparison of the antagonistic activities of tamsulosin and terazosin against human vascular alpha1-adrenoceptors.


    Harada, K; Ohmori, M; Kitoh, Y; Sugimoto, K; Fujimura, A


    Tamsulosin, a selective alpha1A-adrenoceptor antagonist, and terazosin, a non-selective one, are effective for the treatment of urinary disturbance due to benign prostatic hypertrophy. In the present study, their alpha1-adrenoceptor-blocking effects on blood vessels, which may cause orthostatic hypotension, were investigated in 10 healthy males. After the subjects took orally 0.2 mg of tamsulosin, 1 mg of terazosin or a lactate capsule as the control in a randomized cross-over fashion, their finger tip vasoconstrictor response to cold stimulation and vasoconstrictor response of the dorsal hand vein to increasing doses of phenylephrine were examined. The finger tip vasoconstrictor response was significantly reduced and the infusion rate of phenylephrine producing a half-maximal constriction was significantly increased by terazosin, but tamsulosin had no significant effect on these parameters. These data suggest that the usual dose of tamsulosin exerts little alpha1-adrenoceptor-blocking activity on blood vessels, and orthostatic episodes might be mild, if any, during the treatment with tamsulosin. PMID:10461765

  15. Modulatory role of a constitutively active population of alpha(1D)-adrenoceptors in conductance arteries.


    Ziani, Khalid; Gisbert, Regina; Noguera, Maria Antonia; Ivorra, Maria Dolores; D'Ocon, Pilar


    A constitutively active population of alpha(1D)-adrenoceptors in iliac and proximal, distal, and small mesenteric rat arteries was studied. The increase in resting tone (IRT) that evidences it was observed only in iliac and proximal mesenteric and was inhibited by prazosin (pIC(50) = 9.57), 5-methylurapidil (pIC(50) = 7.61), and BMY 7378 (pIC(50) = 8.77). Chloroethylchlonidine (100 micromol/l) did not affect IRT, but when added before the other antagonists it blocked their effect. The potency shown by BMY 7378 confirms the alpha(1D)-subtype as responsible for IRT. BMY 7378 displayed greater inhibition of adrenergic responses in iliac (pIC(50) = 7.57 +/- 0.11) and proximal mesenteric arteries (pIC(50) = 8.05 +/- 0.2) than in distal (pIC(50) = 6.94 +/- 0.13) or small mesenteric arteries (pIC(50) = 6.30 +/- 0.14), which confirms the functional role of the alpha(1D)-adrenoceptor in iliac and proximal mesenteric arteries. This subtype prevents abrupt changes in iliac and proximal mesenteric artery caliber when the agonist disappears, and this modulatory role is evidenced by the slower decay in the response to norepinephrine after removal. PMID:11788394


    SciTech Connect

    LLOYD, E.R.


    The demolition of a facility historically used for processing and handling transuranic materials is considered. Residual alpha emitting radionuclide contamination poses an exposure hazard if released to the local environment during the demolition. The process of planning for the demolition of this highly alpha contaminated building, 232-Z, included a predemolition modeling analysis of potential exposures. Estimated emission rates were used as input to an air dispersion model to estimate frequencies of occurrence of peak air and surface exposures. Postdemolition modeling was also conducted, based on the actual demolition schedule and conditions. The modeling results indicated that downwind deposition is the main operational limitation for demolition of a highly alpha-contaminated building. During the demolition of 232-Z, airborne radiation and surface contamination were monitored. The resultant non-detect monitoring results indicate a significant level of conservatism in the modeled results. This comparison supports the use of more realistic assumption in the estimating emission rates. The resultant reduction in modeled levels of potential exposures has significant implications in terms of the projected costs of demolition of such structures.

  17. Background canceling surface alpha detector


    MacArthur, Duncan W.; Allander, Krag S.; Bounds, John A.


    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone.

  18. Background canceling surface alpha detector


    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.


    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone. 5 figs.

  19. Dual Effects of Alpha-Arbutin on Monophenolase and Diphenolase Activities of Mushroom Tyrosinase

    PubMed Central

    Qin, Liang; Wu, Yang; Liu, Youting; Chen, Yiming; Zhang, Peng


    The effects of α-arbutin on the monophenolase and diphenolase activities of mushroom tyrosinase were investigated. The results showed that α-arbutin inhibited monophenolase activity but it activated diphenolase activity. For monophenolase activity, IC50 value was 4.5 mmol·L−1 and 4.18 mmol·L−1 of α-arbutin could extend the lag time from 40.5 s to 167.3 s. Alpha- arbutin is proposed to be regarded as a triphenolic substrate by the enzyme during catalyzation, leading to the suicide inactivation of the active site of tyrosinase. For diphenolase activity, α-arbutin acted as an activator and its activation mechanism was mixed type activation. To reveal such activation, it should be mainly refered to the conformational changes in tyrosinase caused by the interaction of α-arbutin with residues located at the entrance to the active site, and the decrease of the effect of suicide inactivation. PMID:25303458

  20. Improved activity and modulated action pattern obtained by random mutagenesis at the fourth beta-alpha loop involved in substrate binding to the catalytic (beta/alpha)8-barrel domain of barley alpha-amylase 1.


    Matsui, I; Svensson, B


    The functionality of the sequence Arg183-Gly184-Tyr185 of the substrate binding fourth beta-alpha loop in the (beta/alpha)8-barrel of barley alpha-amylase isozyme 1 (AMY1) was studied by random mutagenesis. A motif of polar Gly184 hydrophobic residues was present in active mutants, selected by starch plate screening of yeast transformants. Gly184 was important, probably due to the carbonyl group binding to Ca2+ and the spatial proximity of Phe181. Mutation of both flanking residues as in Ser183-Gly184-Met185 (SGM-) and TGL-AMY1 decreased the Ca2+ affinity. SGM-AMY1 has 2-fold increased activity for amylose but reduced activity on maltooligosaccharides, whereas KGY-AMY1 has up to 3-fold elevated activity toward the oligosaccharides. TGL-AMY1 has modest activity on all substrates. Shifted action pattern on maltooligosaccharides for NGY-, SGM-, and TGL-AMY1 support that Arg183 in wild type is located at subsites +1 and +2, accommodating two sugar rings toward the reducing end from the site of cleavage. In the crystal structure of barley alpha-amylase 2 (AMY2), Lys182 (equivalent to AMY1 Arg183) is hydrogen-bonded with sugar OH-3 in subsite +2. Higher Ki app for acarbose inhibition of KGY-AMY1 and parent AMY1 compared with the other mutants suggests favorable substrate interactions for Arg/Lys183. KGY-AMY1 was not inhibited by the AMY2-specific proteinaceous barley alpha-amylase/subtilisin inhibitor, although Lys182 of AMY2 is salt-linked to the inhibitor. PMID:9278396

  1. Tat-APE1/ref-1 protein inhibits TNF-{alpha}-induced endothelial cell activation

    SciTech Connect

    Song, Yun Jeong; Lee, Ji Young; Joo, Hee Kyoung; Kim, Hyo Shin; Lee, Sang Ki; Lee, Kwon Ho; Cho, Chung-Hyun; Park, Jin Bong; Jeon, Byeong Hwa


    Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/ref-1) is a multifunctional protein involved both in DNA base excision repair and redox regulation. In this study we evaluated the protective role of Tat-mediated APE1/ref-1 transduction on the tumor necrosis factor (TNF)-{alpha}-activated endothelial activation in cultured human umbilical vein endothelial cells. To construct Tat-APE1/ref-1 fusion protein, human full length of APE1/ref-1 was fused with Tat-protein transduction domain. Purified Tat-APE1/ref-1 fusion protein efficiently transduced cultured endothelial cells in a dose-dependent manner and reached maximum expression at 1 h after incubation. Transduced Tat-APE1/ref-1 showed inhibitory activity on the TNF-{alpha}-induced monocyte adhesion and vascular cell adhesion molecule-1 expression in cultured endothelial cells. These results suggest Tat-APE1/ref-1 might be useful to reduce vascular endothelial activation or vascular inflammatory disorders.

  2. Pathogenic significance of alpha-N-acetylgalactosaminidase activity found in the hemagglutinin of influenza virus.


    Yamamoto, Nobuto; Urade, Masahiro


    Serum vitamin D3-binding protein (Gc protein) is the precursor for the principal macrophage activating factor (MAF). The precursor activity of serum Gc protein was reduced in all influenza virus-infected patients. These patient sera contained alpha-N-acetylgalactosaminidase (Nagalase) that deglycosylates Gc protein. Deglycosylated Gc protein cannot be converted to MAF, thus it loses the MAF precursor activity, leading to immunosuppression. An influenza virus stock contained a large amount of Nagalase activity. A sucrose gradient centrifugation analysis of the virus stock showed that the profile of Nagalase activity corresponds to that of hemagglutinating activity. When these gradient fractions were treated with 0.01% trypsin for 30 min, the Nagalase activity of each fraction increased significantly, suggesting that the Nagalase activity resides on an outer envelope protein of the influenza virion and is enhanced by the proteolytic process. After disruption of influenza virions with sodium deoxycholate, fractionation of the envelope proteins with mannose-specific lectin affinity column along with electrophoretic analysis of the Nagalase peak fraction revealed that Nagalase is the intrinsic component of the hemagglutinin (HA). Cloned HA protein exhibited Nagalase activity only if treated with trypsin. Since both fusion capacity and Nagalase activity of HA protein are expressed by proteolytic cleavage, Nagalase activity appears to be an enzymatic basis for the fusion process. Thus, Nagalase plays dual roles in regulating both infectivity and immunosuppression. PMID:15848273

  3. Serine proteinase inhibition by the active site titrant N alpha-(N, N-dimethylcarbamoyl)-alpha-azaornithine p-nitrophenyl ester. A comparative study.


    Ascenzi, P; Balliano, G; Gallina, C; Polticelli, F; Bolognesi, M


    Kinetics for the hydrolysis of the chromogenic active-site titrant N alpha-(N,N-dimethylcarbamoyl)-alpha-azaornithine p-nitrophenyl ester (Dmc-azaOrn-ONp) catalysed by bovine beta-trypsin, bovine alpha-thrombin, bovine Factor Xa, human alpha-thrombin, human Factor Xa, human Lys77-plasmin, human urinary kallikrein, Mr 33 000 and Mr 54 000 species of human urokinase, porcine pancreatic beta-kallikrein-A and -B and Ancrod (the coagulating serine proteinase from the Malayan pit viper Agkistrodon rhodostoma venom) have been obtained between pH 6.0 and 8.0, at 21.0 degrees C, and analysed in parallel with those for the enzymatic cleavage of N alpha-(N,N-dimethylcarbamoyl)-alpha-azalysine p-nitrophenyl ester (Dmc-azaLys-ONp). The enzyme kinetics are consistent with the minimum three-step catalytic mechanism of serine proteinases, the rate-limiting step being represented by the deacylation process. Bovine beta-trypsin kinetics are modulated by the acid-base equilibrium of the His57 catalytic residue (pKa approximately 6.9). Dmc-azaOrn-ONp and Dmc-azaLys-ONp bind stoichiometrically to the serine proteinase active site, and allow the reliable determination of the active enzyme concentration between 1.0 x 10-6 M and 3.0 x 10-4 M. The affinity and the reactivity for Dmc-azaOrn-ONp (expressed by Ks and k+2/Ks, respectively) of the serine proteinases considered are much lower than those for Dmc-azaLys-ONp. The very different affinity and reactivity properties for Dmc-azaOrn-ONp and Dmc-azaLys-ONp have been related to the different size of the ornithine/lysine side chains, and to the ensuing different positioning of the active-site titrants upon binding to the enzyme catalytic centre (i.e. to P1-S1 recognition). These data represent the first detailed comparative investigation on the catalytic properties of serine proteinases towards an ornithine derivative (i. e. Dmc-azaOrn-ONp). PMID:10672036

  4. Characteristics of chemical binding to alpha 2u-globulin in vitro--evaluating structure-activity relationships

    SciTech Connect

    Borghoff, S.J.; Miller, A.B.; Bowen, J.P.; Swenberg, J.A. )


    alpha 2u-Globulin (alpha 2u) has been shown to accumulate in the kidneys of male rats treated with 2,2,4-trimethylpentane (TMP). 2,4,4-Trimethyl-2-pentanol (TMP-2-OH), a metabolite of TMP, is found reversibly bound to alpha 2u isolated from the kidneys of these treated rats. The objectives of the following study were to characterize the ability of (3H)TMP-2-OH to bind to alpha 2u in vitro and to determine whether other compounds that cause this protein to accumulate have the same binding characteristics. Although compounds that have been shown to cause the accumulation of alpha 2u in male rat kidneys compete in vitro with (3H)TMP-2-OH for binding to alpha 2u, they do so to varying degrees. The binding affinity (Kd) of the (3H)TMP-2-OH-alpha 2u complex was calculated to be on the order of 10(-7) M. The inhibition constant values (Ki) determined for d-limonene, 1,4-dichlorobenzene, and 2,5-dichlorophenol were all in the range 10(-4) M, whereas the Ki values for isophorone, 2,4,4- or 2,2,4-trimethyl-1-pentanol, and d-limonene oxide were determined to be in the range 10(-6) and 10(-7) M, respectively. TMP and 2,4,4- and 2,2,4-trimethylpentanoic acid did not compete for binding. This suggests that other factors, besides binding, are involved in the accumulation of alpha 2u. In this study the ability of a chemical to bind to alpha 2u was used as a measure of biological activity to assess structure-activity relationships among the chemicals tested and known to cause the accumulation of alpha 2u. The results so far suggest that binding is dependent on both hydrophobic interactions and hydrogen bonding.

  5. Uncoupling protein-2 up-regulation and enhanced cyanide toxicity are mediated by PPAR{alpha} activation and oxidative stress

    SciTech Connect

    Zhang, X.; Li, L.; Prabhakaran, K.; Zhang, L.; Leavesley, H.B.; Borowitz, J.L.; Isom, G.E.


    Uncoupling protein 2 (UCP-2) is an inner mitochondrial membrane proton carrier that modulates mitochondrial membrane potential ({delta}{psi}{sub m}) and uncouples oxidative phosphorylation. We have shown that up-regulation of UCP-2 by Wy14,643, a selective peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) agonist, enhances cyanide cytotoxicity. The pathway by which Wy14,643 up-regulates UCP-2 was determined in a dopaminergic cell line (N27 cells). Since dopaminergic mesencephalic cells are a primary brain target of cyanide, the N27 immortalized mesencephalic cell was used in this study. Wy14,643 produced a concentration- and time-dependent up-regulation of UCP-2 that was linked to enhanced cyanide-induced cell death. MK886 (PPAR{alpha} antagonist) or PPAR{alpha} knock-down by RNA interference (RNAi) inhibited PPAR{alpha} activity as shown by the peroxisome proliferator response element-luciferase reporter assay, but only partially decreased up-regulation of UCP-2. The role of oxidative stress as an alternative pathway to UCP-2 up-regulation was determined. Wy14,643 induced a rapid surge of ROS generation and loading cells with glutathione ethyl ester (GSH-EE) or pre-treatment with vitamin E attenuated up-regulation of UCP-2. On the other hand, RNAi knockdown of PPAR{alpha} did not alter ROS generation, suggesting a PPAR{alpha}-independent component to the response. Co-treatment with PPAR{alpha}-RNAi and GSH-EE blocked both the up-regulation of UCP-2 by Wy14,643 and the cyanide-induced cell death. It was concluded that a PPAR{alpha}-mediated pathway and an oxidative stress pathway independent of PPAR{alpha} mediate the up-regulation of UCP-2 and subsequent increased vulnerability to cyanide-induced cytotoxicity.


    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intracardiac accumulation of lipid and related intermediates (e.g., ceramide) is associated with cardiac dysfunction and may contribute to the progression of heart failure (HF). Overexpression of nuclear receptor peroxisome proliferator-activated receptor-alpha (PPAR-alpha) increases intramyocellula...

  7. TNF-alpha-induced mitochondrial alterations in human T cells requires FADD and caspase-8 activation but not RIP and caspase-3 activation.


    Shakibaei, Mehdi; Sung, Bokyung; Sethi, Gautam; Aggarwal, Bharat B


    Although much is known about how TNF-alpha induces apoptosis in the presence of inhibitors of protein synthesis, little is known about how it induces apoptosis without these inhibitors. In this report we investigated temporal sequence of events induced by TNF-alpha in the absence of protein synthesis. Regardless of whether we measured the effects by plasma membrane phosphotidylserine accumulation, by DNA strand breaks, or activation of caspases, significant changes were observed only between 12-24 h of TNF-alpha treatment. One of the earliest changes observed after TNF-alpha treatment was mitochondrial swelling at 10 min; followed by cytochrome c and Smac release at 10-30 min, and then heterochromatin clumping occurred at 60 min. While genetic deletion of receptor-interaction protein (RIP) had no effect on TNF-alpha-induced mitochondrial damage, deletion of Fas-associated death domain (FADD) abolished the TNF-induced mitochondrial swelling. Since pan-caspase inhibitor z-VAD-fmk abolished the TNF-alpha-induced mitochondrial changes, z-DEVD-fmk, an inhibitor of caspase-3 had no effect, suggesting that TNF-alpha-induced mitochondrial changes or cytochrome c and Smac release requires caspase-8 but not caspase-3 activation. Overall, our results indicated that mitochondrial changes are early events in TNF-alpha-induced apoptosis and that these mitochondrial changes require recruitment of FADD and caspase-8 activation, but not caspase-3 activation or RIP recruitment. PMID:20136500

  8. Paxillin binding to the alpha 4 integrin subunit stimulates LFA-1 (integrin alpha L beta 2)-dependent T cell migration by augmenting the activation of focal adhesion kinase/proline-rich tyrosine kinase-2.


    Rose, David M; Liu, Shouchun; Woodside, Darren G; Han, Jaewon; Schlaepfer, David D; Ginsberg, Mark H


    Engagement of very late Ag-4 (integrin alpha(4)beta(1)) by ligands such as VCAM-1 markedly stimulates leukocyte migration mediated by LFA-1 (integrin alpha(L)beta(2)). This form of integrin trans-regulation in T cells requires the binding of paxillin to the alpha(4) integrin cytoplasmic domain. This conclusion is based on the abolition of trans-regulation in Jurkat T cells by an alpha(4) mutation (alpha(4)(Y991A)) that disrupts paxillin binding. Furthermore, cellular expression of an alpha(4)-binding fragment of paxillin that blocks the alpha(4)-paxillin interaction, selectively blocked VCAM-1 stimulation of alpha(L)beta(2)-dependent cell migration. The alpha(4)-paxillin association mediates trans-regulation by enhancing the activation of tyrosine kinases, focal adhesion kinase (FAK) and/or proline-rich tyrosine kinase-2 (Pyk2), based on two lines of evidence. First, disruption of the paxillin-binding site in the alpha(4) tail resulted in much less alpha(4)beta(1)-mediated phosphorylation of Pyk2 and FAK. Second, transfection with cDNAs encoding C-terminal fragments of Pyk2 and FAK, which block the function of the intact kinases, blocked alpha(4)beta(1) stimulation of alpha(L)beta(2)-dependent migration. These results define a proximal protein-protein interaction of an integrin cytoplasmic domain required for trans-regulation between integrins, and establish that augmented activation of Pyk2 and/or FAK is an immediate signaling event required for the trans-regulation of integrin alpha(L)beta(2) by alpha(4)beta(1). PMID:12794117

  9. Peroxisome proliferator-activated receptor {alpha} agonist-induced down-regulation of hepatic glucocorticoid receptor expression in SD rats

    SciTech Connect

    Chen Xiang; Li Ming; Sun Weiping; Bi Yan; Cai Mengyin; Liang Hua; Yu Qiuqiong; He Xiaoying; Weng Jianping


    It was reported that glucocorticoid production was inhibited by fenofibrate through suppression of type-1 11{beta}-hydroxysteroid dehydrogenase gene expression in liver. The inhibition might be a negative-feedback regulation of glucocorticoid receptor (GR) activity by peroxisome proliferator-activated receptor alpha (PPAR{alpha}), which is quickly induced by glucocorticoid in the liver. However, it is not clear if GR expression is changed by fenofibrate-induced PPAR{alpha} activation. In this study, we tested this possibility in the liver of Sprague-Dawley rats. GR expression was reduced by fenofibrate in a time- and does-dependent manner. The inhibition was observed in liver, but not in fat and muscle. The corticosterone level in the blood was increased significantly by fenofibrate. These effects of fenofibrate were abolished by PPAR{alpha} inhibitor MK886, suggesting that fenofibrate activated through PPAR{alpha}. In conclusion, inhibition of GR expression may represent a new molecular mechanism for the negative feedback regulation of GR activity by PPAR{alpha}.

  10. The low density lipoprotein receptor-related protein/alpha2-macroglobulin receptor regulates cell surface plasminogen activator activity on human trophoblast cells.


    Zhang, J C; Sakthivel, R; Kniss, D; Graham, C H; Strickland, D K; McCrae, K R


    The low density lipoprotein receptor-related protein/alpha2-macroglobulin receptor (LRP/alpha2MR) mediates the internalization of numerous ligands, including prourokinase (pro-UK) and complexes between two-chain urokinase (tc-u-PA) and plasminogen activator inhibitor type-1 (PAI-1). It has been suggested that through its ability to internalize these ligands, LRP/alpha2MR may regulate the expression of plasminogen activator activity on cell surfaces; this hypothesis, however, has not been experimentally confirmed. To address this issue, we assessed the ability of LRP/alpha2MR to regulate plasminogen activator activity on human trophoblast cells, which express both LRP/alpha2MR and the urokinase receptor (uPAR). Trophoblasts internalized and degraded exogenous 125I-pro-UK (primarily following its conversion to tc-u-PA and incorporation into tc-u-PA.PAI complexes) in an LRP/alpha2MR-dependent manner, which was inhibited by the LRP/alpha2MR receptor-associated protein. Receptor-associated protein also caused a approximately 50% reduction in cell surface plasminogen activator activity and delayed the regeneration of unoccupied uPAR by cells on which uPAR were initially saturated with pro-UK. Identical effects were caused by anti-LRP/alpha2MR antibodies. These results demonstrate that LRP/alpha2MR promotes the expression of cell surface plasminogen activator activity on trophoblasts by facilitating the clearance of tc-u-PA.PAI complexes and regeneration of unoccupied cell surface uPAR. PMID:9822706