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Author (up) Bourne, G.L.; Grainger, D.J. file  url
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  Title Development and characterisation of an assay for furin activity Type Journal Article
  Year 2011 Publication Journal of Immunological Methods Abbreviated Journal J Immunol Methods  
  Volume 364 Issue 1-2 Pages 101-108  
  Keywords Anoxia/diagnosis/genetics/*metabolism; Antibodies/immunology/*metabolism; Biochemistry/methods; Cell Extracts/chemistry; Furin/*genetics/immunology/*metabolism; Gene Expression Regulation, Enzymologic; Hep G2 Cells; Humans; Immunomodulation; *Immunosorbent Techniques; RNA, Messenger/*analysis; Reference Standards; Sensitivity and Specificity; Transforming Growth Factor beta/immunology/metabolism  
  Abstract Furin is a serine endoprotease that is responsible for the proteolytic processing of proteins within the secretory pathway, including cytokines, hormones, integrins, other proteases, and also pathogen-derived proteins. It is likely that the level of furin activity determines the extent of processing of these substrates. Furin is ubiquitously expressed across all tissues, at low levels, but can be induced in response to environmental cues such as hypoxia and cytokine stimulation. However, all studies to date that have investigated furin expression have been limited to analysis of furin mRNA; there has been no assay sensitive enough to quantify endogenous furin. Though activity-based assays have been described for furin-like enzyme activity, we demonstrate that these assays are dominated by the activity of other enzymes and cannot be used to approximate furin activity. A sensitive and specific assay for furin activity was therefore developed and characterised, using an antibody capture step to immobilise furin from whole cell lysates. Furin activity is quantified relative to that of recombinant active furin protein, to allow estimation of active furin protein concentration. The assay has a minimum detection limit of 0.006 nM; sensitive enough to determine the furin activity of many of the cell lines tested. The specificity of the assay was demonstrated by genetic modulation of furin expression. Furthermore, the assay was used to demonstrate that the cytokine transforming growth factor beta (TGF-beta) stimulates increased furin activity in HepG2 cells, confirming and extending previous reports that TGF-beta increases furin expression, and adding to the mounting body of evidence that cellular furin activity can be modulated.  
  Call Number Serial 525  
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Author (up) Boyd, W.A.; Cole, R.D.; Anderson, G.L.; Williams, P.L. file  url
openurl 
  Title The effects of metals and food availability on the behavior of Caenorhabditis elegans Type Journal Article
  Year 2003 Publication Environmental Toxicology and Chemistry / SETAC Abbreviated Journal Environ Toxicol Chem  
  Volume 22 Issue 12 Pages 3049-3055  
  Keywords Animals; Biological Assay; Cadmium/*toxicity; *Caenorhabditis elegans; Copper/*toxicity; *Environmental Exposure; *Feeding Behavior; Lead/*toxicity; Sensitivity and Specificity; Starvation; Water Pollutants/*toxicity  
  Abstract Caenorhabditis elegans, a nonparasitic soil nematode, was used to assess the combined effects of metal exposures and food availability on behavior. Movement was monitored using a computer tracking system after exposures to Cu, Pb, or Cd while feeding was measured as a change in optical density (deltaOD) of bacteria suspensions over the exposure period. After 24-h exposures at high and low bacteria concentrations, movement was decreased in a concentration-dependent fashion by Pb and Cd but feeding reductions were not directly proportional to exposure concentrations. Copper exposure induced concentration-dependent declines in feeding and movement regardless of bacteria concentration. The impact of 24-h metal exposures was apparently reduced by increasing food availability. Therefore, exposures were shortened to 4 h in an attempt to minimize starvation effects on movement. Although nematodes were immobilized following 24 h of food depravation, worms deprived of food during the 4-h exposure continued to feed and move after exposure. A bead-ingestion assay after 4-h exposures was also used as an additional means of assessing the effects of metals on feeding behavior. Ingestion was significantly reduced by all concentrations of metals tested, indicating its sensitivity as a sublethal assay. Feeding (deltaOD) during exposures exhibited similar trends as ingestion but was slightly less sensitive, while movement was the least sensitive assay of 4-h metal exposures to C. elegans. Assessment of multiple sublethal endpoints allowed for the determination of the separate and interactive effects of metals and food availability on C. elegans behavior.  
  Call Number Serial 1031  
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Author (up) Burkart, M.R.; Stoner, J.D. file  url
openurl 
  Title Nitrate in aquifers beneath agricultural systems Type Journal Article
  Year 2007 Publication Water Science and Technology : a Journal of the International Association on Water Pollution Research Abbreviated Journal Water Sci Technol  
  Volume 56 Issue 1 Pages 59-69  
  Keywords *Agriculture; Animals; Fertilizers; Inorganic Chemicals; Nitrates/*analysis; Sensitivity and Specificity; Trisaccharides; Water Pollutants, Chemical/*analysis; Water Supply/*analysis  
  Abstract Research from several regions of the world provides spatially anecdotal evidence to hypothesize which hydrologic and agricultural factors contribute to groundwater vulnerability to nitrate contamination. Analysis of nationally consistent measurements from the U.S. Geological Survey's NAWQA program confirms these hypotheses for a substantial range of agricultural systems. Shallow unconfined aquifers are most susceptible to nitrate contamination associated with agricultural systems. Alluvial and other unconsolidated aquifers are the most vulnerable and also shallow carbonate aquifers that provide a substantial but smaller contamination risk. Where any of these aquifers are overlain by permeable soils the risk of contamination is larger. Irrigated systems can compound this vulnerability by increasing leaching facilitated by additional recharge and additional nutrient applications. The system of corn, soybean, and hogs produced significantly larger concentrations of groundwater nitrate than all other agricultural systems because this system imports the largest amount of N-fertilizer per unit production area. Mean nitrate under dairy, poultry, horticulture, and cattle and grains systems were similar. If trends in the relation between increased fertilizer use and groundwater nitrate in the United States are repeated in other regions of the world, Asia may experience increasing problems because of recent increases in fertilizer use. Groundwater monitoring in Western and Eastern Europe as well as Russia over the next decade may provide data to determine if the trend in increased nitrate contamination can be reversed. If the concentrated livestock trend in the United States is global, it may be accompanied by increasing nitrogen contamination in groundwater. Concentrated livestock provide both point sources in the confinement area and intense non-point sources as fields close to facilities are used for manure disposal. Regions where irrigated cropland is expanding, such as in Asia, may experience the greatest impact of this practice on groundwater nitrate.  
  Call Number Serial 117  
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Author (up) Cross, G.H.; Reeves, A.A.; Brand, S.; Popplewell, J.F.; Peel, L.L.; Swann, M.J.; Freeman, N.J. file  url
openurl 
  Title A new quantitative optical biosensor for protein characterisation Type Journal Article
  Year 2003 Publication Biosensors & Bioelectronics Abbreviated Journal Biosens Bioelectron  
  Volume 19 Issue 4 Pages 383-390  
  Keywords Antibodies/analysis/chemistry; Biosensing Techniques/*instrumentation/methods; Biotin/analysis/chemistry; Equipment Design; *Equipment Failure Analysis; Humans; Interferometry/*instrumentation/methods; Optics and Photonics/*instrumentation; Proteins/*analysis/*chemistry; Reproducibility of Results; Sensitivity and Specificity; Streptavidin/analysis/chemistry  
  Abstract A new optical biosensor is described based on a dual waveguide interferometric technique. By addressing the waveguide structure with alternate polarisations the optogeometrical properties (density and thickness) of adsorbed protein layers at the sensor (solid)-liquid interface have been determined. Differences in the waveguide mode dispersion between the transverse electric (TE) and transverse magnetic (TM) modes allow unique solutions for adlayer thickness and refractive index to be determined at all stages during the formation process. The technique has been verified using standard protein systems and by comparing the data with published work using X-ray crystallography and neutron reflection techniques. The data obtained was found to be in excellent agreement with previously reported X-ray experiments given that typical film thicknesses for streptavidin layers were in the range 5.5-6.5 nm compared with the short axis crystal structure of between 4.8 and 5.6 nm. The precision of the measurements taken was of the order of 40 pm with respect to adsorbed adlayer thicknesses. This biosensor approach provides measurements of both thickness and density of adlayers to a high precision, simultaneously and in real time enabling detail of the structure and function of proteins to be elucidated. From such data it is possible to obtain information on the orientation, distortion and efficiency of immobilisation procedures as well as the interaction event of interest. The technique is expected to find utility with those interested in protein structure and function. This is an area of growing importance within the life sciences as the demand for quantitative analytical techniques increases with the growth in “proteomics”.  
  Call Number Serial 981  
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Author (up) Elaad, E.; Ben-Shakhar, G. file  url
openurl 
  Title Finger pulse waveform length in the detection of concealed information Type Journal Article
  Year 2006 Publication International Journal of Psychophysiology : Official Journal of the International Organization of Psychophysiology Abbreviated Journal Int J Psychophysiol  
  Volume 61 Issue 2 Pages 226-234  
  Keywords Adult; Arousal/*physiology; Attention/*physiology; Autonomic Nervous System/physiology; Female; Galvanic Skin Response/*physiology; *Guilt; Habituation, Psychophysiologic/physiology; Heart Rate/*physiology; Humans; Lie Detection/*psychology; Male; Mathematical Computing; Orientation/physiology; Plethysmography/statistics & numerical data; Problem Solving/*physiology; Pulse/*statistics & numerical data; Reference Values; *Respiration; Sensitivity and Specificity; Theft/*psychology  
  Abstract An attempt was made to assess the efficiency of the finger pulse waveform length (FPWL), in detection of concealed information. For this purpose, two mock-theft experiments were designed. In the first, 40 guilty participants were examined while electrodermal, respiration and finger pulse volume were recorded. Results showed that detection accuracy with the FPWL was at least as good as the accuracy obtained with the other two measures (respiration changes and skin conductance responses). Detection efficiency was further improved when a combination of FPWL with the other two measures was used. In the second experiment, 39 guilty and 23 innocent participants were instructed to deny knowledge while the transducers were not attached to them. Then, the same questions were repeated while electrodermal, respiration and finger pulse volume were recorded. Results showed reduced rates of identification compared to the first experiment, which were explained by habituation. However, finger pulse was less affected by habituation than both respiration and skin conductance. Results suggested that the FPWL might be a useful addition to the existing measures in the detection of concealed information.  
  Call Number Serial 1443  
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