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131.
164 feed samples were collected in Lower Austria, Upper Austria, Styria and Carynthia in the crop years 2002 and 2003 and were analysed by means of the RIDASCREEN® ELISA-assay for theFusarium toxins Deoxynivalenol (DON) and Zearalenone (ZON). The collected samples consisted of swine feeds, cereals and silages. DON concentrations were found up to the range of mg/kg (ppm), in contrast ZON results remained significantly lower. 相似文献
132.
Shivani M Chidrawar Naeem Khan Y L Tracey Chan Laxman Nayak Paul AH Moss 《Immunity & ageing : I & A》2006,3(1):10-8
Background
Natural killer (NK) cells are cytotoxic lymphocytes that lack CD3 and express variable levels of CD16, CD56 and CD57. In recent years NK cells have been categorised into two major groups based on the level of CD56 expression. This phenotypic classification correlates with functional activity as CD56bright NK cells are the major cytokine producing subset whereas CD56dim NK cells exhibit greater cytotoxic activity. Previous studies have revealed a reduction in total NK cell numbers in association with ageing and this study sought to determine the potential influence of ageing on the number of NK cell subsets within peripheral blood. 相似文献133.
Benz PM Blume C Moebius J Oschatz C Schuh K Sickmann A Walter U Feller SM Renné T 《The Journal of cell biology》2008,180(1):205-219
Directed cortical actin assembly is the driving force for intercellular adhesion. Regulated by phosphorylation, vasodilator-stimulated phosphoprotein (VASP) participates in actin fiber formation. We screened for endothelial proteins, which bind to VASP, dependent on its phosphorylation status. Differential proteomics identified αII-spectrin as such a VASP-interacting protein. αII-Spectrin binds to the VASP triple GP5-motif via its SH3 domain. cAMP-dependent protein kinase–mediated VASP phosphorylation at Ser157 inhibits αII-spectrin–VASP binding. VASP is dephosphorylated upon formation of cell–cell contacts and in confluent, but not in sparse cells, αII-spectrin colocalizes with nonphosphorylated VASP at cell–cell junctions. Ectopic expression of the αII-spectrin SH3 domain at cell–cell contacts translocates VASP, initiates cortical actin cytoskeleton formation, stabilizes cell–cell contacts, and decreases endothelial permeability. Conversely, the permeability of VASP-deficient endothelial cells (ECs) and microvessels of VASP-null mice increases. Reconstitution of VASP-deficient ECs rescues barrier function, whereas αII-spectrin binding-deficient VASP mutants fail to restore elevated permeability. We propose that αII-spectrin–VASP complexes regulate cortical actin cytoskeleton assembly with implications for vascular permeability. 相似文献
134.
Valérie Simonneaux AH Ouichou Cheryl Craft Paul Pévet 《Journal of neurochemistry》1994,62(6):2464-2471
Abstract: Neuropeptide Y is colocalized with noradrena-line in sympathetic fibers innervating the rat pineal gland. In this article we present a study of the effects and mechanisms of action of neuropeptide Y on the pineal noradrenergic transmission, the main input leading to the rhythmic secretion of melatonin. At the presynaptic level, neuropeptide Y inhibits by 45%, with an EC50 of 50 n M , the potassium-evoked noradrenaline release from pineal nerve endings. This neuropeptide Y inhibition occurs via the activation of pertussis toxin-sensitive G protein-coupled neuropeptide Y-Y2 receptors and is independent from, but additive to, the α2 -adrenergic inhibition of noradrenaline release. At the postsynaptic level, neuropeptide Y decreases by a maximum of 35%, with an EC50 of 5 n M , the β-adrenergic induction of cyclic AMP elevation via the activation of neuropeptide Y-Y1 receptors. This moderate neuropeptide Y-induced inhibition of cyclic AMP accumulation, however, has no effect on the melatonin secretion induced by a β-adrenergic stimulation. On the contrary, in the presence of 1 m M ascorbic acid, neuropeptide Y potentiates (up to threefold) the melatonin secretion. In conclusion, this study has demonstrated that neuropeptide Y modulates the noradrenergic transmission in the rat pineal gland at both presynaptic and postsynaptic levels, using different receptor subtypes and transduction pathways. 相似文献
135.
M. Schuh 《Mycotoxin Research》1987,3(1):69-73
A surveillance study of the most important fusarium-toxins in Austrian feed samples, the estrogenic mycotoxin zearalenone (F-2 toxin) as well as the refusal of feed causing deoxynivalenol (vomitoxin), of the last 8 years is given. The author describes predominantly the biologic effects in swine, cattle and poultry from the practical point of view and the correlation between clinical symptoms of the incriminated animals and the mycotoxin-levels found in the suspicious feed samples. Some field cases, the clinical symptoms and the fusariumtoxin-concentrations found are presented in one table. 相似文献
136.
137.
Bruce R. Korf Barbara E. Schuh Martin J. Salwen Dorothy Warburton Orlando J. Miller 《Human genetics》1976,31(1):27-33
Summary The role of trypsin in the elicitation of G-banding on human chromosomes was studied in two separate laboratories. Enzyme activity and ability of trypsin to chelate calcium were manipulated by dilution of the treatment solution, and by inhibition with diisopropylphosphofluoridate, diphenylcarbamyl chloride, or soybean trypsin inhibitor. In all cases, chromosomes were affected in proportion to the enzyme activity of the treatment solution rather than the ability of the solution to bind calcium. It is concluded that calcium chelation is not sufficient to explain G-banding by trypsin, but that proteolytic activity is required. 相似文献
138.
Kathy Boutis Paul Grootendorst Andrew Willan Amy C. Plint Paul Babyn Robert J. Brison Arun Sayal Melissa Parker Natalie Mamen Suzanne Schuh Jeremy Grimshaw David Johnson Unni Narayanan 《CMAJ》2013,185(15):E731-E738
Background:
The Low Risk Ankle Rule is a validated clinical decision rule that has the potential to safely reduce radiography in children with acute ankle injuries. We performed a phased implementation of the Low Risk Ankle Rule and evaluated its effectiveness in reducing the frequency of radiography in children with ankle injuries.Methods:
Six Canadian emergency departments participated in the study from Jan. 1, 2009, to Aug. 31, 2011. At the 3 intervention sites, there were 3 consecutive 26-week phases. In phase 1, no interventions were implemented. In phase 2, we activated strategies to implement the ankle rule, including physician education, reminders and a computerized decision support system. In phase 3, we included only the decision support system. No interventions were introduced at the 3 pair-matched control sites. We examined the management of ankle injuries among children aged 3–16 years. The primary outcome was the proportion of children undergoing radiography.Results:
We enrolled 2151 children with ankle injuries, 1055 at intervention and 1096 at control hospitals. During phase 1, the baseline frequency of pediatric ankle radiography at intervention and control sites was 96.5% and 90.2%, respectively. During phase 2, the frequency of ankle radiography decreased significantly at intervention sites relative to control sites (between-group difference −21.9% [95% confidence interval [CI] −28.6% to −15.2%]), without significant differences in patient or physician satisfaction. All effects were sustained in phase 3. The sensitivity of the Low Risk Ankle Rule during implementation was 100% (95% CI 85.4% to 100%), and the specificity was 53.1% (95% CI 48.1% to 58.1%).Interpretation:
Implementation of the Low Risk Ankle Rule in several different emergency department settings reduced the rate of pediatric ankle radiography significantly and safely, without an accompanying change in physician or patient satisfaction. Trial registration: ClinicalTrials.gov, no. .Pediatric ankle injuries result in more than 2 million emergency department visits in Canada and the United States each year (Jeanette Tyas, Canadian Institute of Health Information: unpublished data, 2007). NCT007858761,2 Radiographs are ordered for 85%–95% of these children,3 although only 12% of these reveal a fracture.4 Thus, radiography is unnecessary for most children’s ankle injuries, and these high rates of radiography needlessly expose children to radiation and are a questionable use of resources.The Low Risk Ankle Rule has 100% sensitivity with respect to identifying clinically important pediatric ankle fractures and has the potential to safely reduce imaging by about 60%.4 When the application of the rule suggests that radiography is not needed, it has been shown that any fractures that might be missed are clinically insignificant and can be safely and cost-effectively managed like an ankle sprain, with superior functional recovery.5 Finally, the Low Risk Ankle Rule has been shown to have excellent acceptability when tested on emergency physicians.6The main objective of this study was to implement the ankle rule in several different emergency department settings using a multimodal knowledge translation strategy and to evaluate its impact on the frequency of radiography in children presenting with acute ankle injuries. 相似文献139.
Espen E. Spangenburg Kathryn C. Jackson Rosemary A. Schuh 《Journal of physiology and biochemistry》2013,69(4):909-917
Activation of 5′ adenosine monophosphate-activated protein kinase (AMPK) with aminoimidazole carboxamide ribonucleotide (AICAR) increases skeletal muscle glucose uptake and fatty acid oxidation. The purpose of these experiments was to utilize AICAR to enhance palmitate consumption by mitochondria in cultured skeletal muscle cells. In these experiments, we treated C2C12 myotubes or adult single skeletal muscle fibers with varying concentrations of AICAR for different lengths of time. Surprisingly, acute AICAR exposure at most concentrations (0.25–1.5 mM), but not all (0.1 mM), modestly inhibited oxygen consumption even though AICAR increased AMPK phosphorylation. The data suggest that AICAR inhibited oxygen consumption by the cultured muscle in a non-specific manner. The results of these experiments are expected to provide valuable information to investigators interested in using AICAR in cell culture studies. 相似文献
140.
The scission of membranes necessary for vesicle biogenesis and cytokinesis is mediated by cytoplasmic proteins, which include members of the ESCRT (endosomal sorting complex required for transport) machinery. During the formation of intralumenal vesicles that bud into multivesicular endosomes, the ESCRT-II complex initiates polymerization of ESCRT-III subunits essential for membrane fission. However, mechanisms underlying the spatial and temporal regulation of this process remain unclear. Here, we show that purified ESCRT-II binds to the ESCRT-III subunit Vps20 on chemically defined membranes in a curvature-dependent manner. Using a combination of liposome co-flotation assays, fluorescence-based liposome interaction studies, and high-resolution atomic force microscopy, we found that the interaction between ESCRT-II and Vps20 decreases the affinity of ESCRT-II for flat lipid bilayers. We additionally demonstrate that ESCRT-II and Vps20 nucleate flexible filaments of Vps32 that polymerize specifically along highly curved membranes as a single string of monomers. Strikingly, Vps32 filaments are shown to modulate membrane dynamics in vitro, a prerequisite for membrane scission events in cells. We propose that a curvature-dependent assembly pathway provides the spatial regulation of ESCRT-III to fuse juxtaposed bilayers of elevated curvature. 相似文献