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143.
Christy E. Oliver Ross C. Beier Michael E. Hume Shane M. Horrocks Thomas A. Casey Joel S. Caton David J. Nisbet David J. Smith Nathan A. Krueger Robin C. Anderson 《Anaerobe》2010,16(2):106-113
Experiments were conducted to determine factors that affect sensitivity of Salmonella enterica serovar Typhimurium to sodium chlorate (5 mM). In our first experiment, cultures grown without chlorate grew more rapidly than those with chlorate. An extended lag before logarithmic growth was observed in anaerobic but not aerobic cultures containing chlorate. Chlorate inhibition of growth during aerobic culture began later than that observed in anaerobic cultures but persisted once inhibition was apparent. Conversely, anaerobic cultures appeared to adapt to chlorate after approximately 10 h of incubation, exhibiting rapid compensatory growth. In anaerobic chlorate-containing cultures, 20% of total viable counts were resistant to chlorate by 6 h and had propagated to 100% resistance (>109 CFU mL?1) by 24 h. In the aerobic chlorate-containing cultures, 12.9% of colonies had detectable resistance to chlorate by 6 h, but only 1% retained detectable resistance at 24 h, likely because these cultures had opportunity to respire on oxygen and were thus not enriched via the selective pressure of chlorate. In another study, treatment with shikimic acid (0.34 mM), molybdate (1 mM) or their combination had little effect on aerobic or anaerobic growth of Salmonella in the absence of added chlorate. As observed in our earlier study, chlorate resistance was not detected in any cultures without added chlorate. Chlorate resistant Salmonella were recovered at equivalent numbers regardless of treatment after 8 h of aerobic or anaerobic culture with added chlorate; however, by 24 h incubation chlorate sensitivity was completely restored to aerobic but not anaerobic cultures treated with shikimic acid or molybdate but not their combination. Results indicate that anaerobic adaptation of S. Typhimurium to sodium chlorate during pure culture is likely due to the selective propagation of low numbers of cells exhibiting spontaneous resistance to chlorate and this resistance is not reversible by molybdenum supplementation. 相似文献
144.
Lagerström MC Rogoz K Abrahamsen B Persson E Reinius B Nordenankar K Olund C Smith C Mendez JA Chen ZF Wood JN Wallén-Mackenzie A Kullander K 《Neuron》2010,68(3):529-542
The natural response to itch sensation is to scratch, which relieves the itch through an unknown mechanism. Interaction between pain and itch has been frequently demonstrated, and the selectivity hypothesis of itch, based on data from electrophysiological and behavioral experiments, postulates the existence of primary pain afferents capable of repressing itch. Here, we demonstrate that deletion of vesicular glutamate transporter (VGLUT) 2 in a subpopulation of neurons partly overlapping with the vanilloid receptor (TRPV1) primary afferents resulted in a dramatic increase in itch behavior accompanied by a reduced responsiveness to thermal pain. The increased itch behavior was reduced by administration of antihistaminergic drugs and by genetic deletion of the gastrin-releasing peptide receptor, demonstrating a dependence on VGLUT2 to maintain normal levels of both histaminergic and nonhistaminergic itch. This study establishes that VGLUT2 is a major player in TRPV1 thermal nociception and also serves to regulate a normal itch response. 相似文献
145.
Tammy Casey Peter S. Solomon Scott Bringans Kar‐Chun Tan Richard P. Oliver Richard Lipscombe 《Proteomics》2010,10(1):38-47
The G protein α‐subunit (Gna1) in the wheat pathogen Stagonospora nodorum has previously been shown to be a critical controlling element in disease ontogeny. In this study, iTRAQ and 2‐D LC MALDI‐MS/MS have been used to characterise protein expression changes in the S. nodorum gna1 strain versus the SN15 wild‐type. A total of 1336 proteins were identified. The abundance of 49 proteins was significantly altered in the gna1 strain compared with the wild‐type. Gna1 was identified as having a significant regulatory role on primary metabolic pathways, particularly those concerned with NADPH synthesis or consumption. Mannitol dehydrogenase was up‐regulated in the gna1 strain while mannitol 1‐phosphate dehydrogenase was down‐regulated providing direct evidence of Gna1 regulation over this enigmatic pathway. Enzymatic analysis and growth assays confirmed this regulatory role. Several novel hypothetical proteins previously associated with stress and pathogen responses were identified as positively regulated by Gna1. A short‐chain dehydrogenase (Sch3) was also significantly less abundant in the gna1 strains. Sch3 was further characterised by gene disruption in S. nodorum by homologous recombination. Functional characterisation of the sch3 strains revealed their inability to sporulate in planta providing a further link to Gna1 signalling and asexual reproduction. These data add significantly to the identification of the regulatory targets of Gna1 signalling in S. nodorum and have demonstrated the utility of iTRAQ in dissecting signal transduction pathways. 相似文献
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Polypyridyl ligands were investigated for their ability to bind and mobilize iron(ii) from ferritin in aqueous solution. Association constants with iron(ii) (pFe(II)) were determined for the pentadentate ligands N4Py (pFe(II) = 14.4) and Bn-TPEN (pFe(II) = 13.7) using a competition method with the hexadentate ligand TPEN (pFe(II) = 14.6, 0.1 M KNO(3)). Ferrous complexes were formed using the polypyridyl ligands and ferritin as the sole iron source in the presence of reductant. The observed rates of iron mobilization from ferritin were dependent on reductant and were higher in the presence of ascorbate than dithiothreitol. TPEN, N4Py and Bn-TPEN demonstrated comparable and in some cases faster rates and higher levels of iron mobilization when compared to the iron(ii) chelator 1,10-phenanthroline, particularly at low concentrations of chelator. 相似文献
148.
Nora M. Casey Dan Milbourne Susanne Barth Melanie Febrer Glyn Jenkins Michael T. Abberton Charlotte Jones Daniel Thorogood 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(3):567-576
White clover (Trifolium repens L.) is a forage legume of considerable economic importance in temperate agricultural systems. It has a strong self-incompatibility
system. The molecular basis of self-incompatibility in T. repens is unknown, but it is under the control of a single locus, which is expressed gametophytically. To locate the self-incompatibility
locus (S locus) in T. repens, we carried out cross-pollination experiments in an F1 mapping population and constructed a genetic linkage map using amplified fragment length polymorphism and simple sequence
repeat markers. As the first step in a map-based cloning strategy, we locate for the first time the S locus in T. repens on a genetic linkage map, on the homoeologous linkage group pair 1 (E), which is broadly syntenic to Medicago truncatula L. chromosome 1. On the basis of this syntenic relationship, the possibility that the S locus may or may not possess an S-RNase gene is discussed. 相似文献
149.
John W Simmons Kevin K Chung Evan M Renz Christopher E White Casey L Cotant Molly A Tilley Mark O Hardin John A Jones Lorne H Blackbourne Steven E Wolf 《BMC anesthesiology》2010,10(1):1-7
Background
We sought to evaluate agreement between a new and widely implemented method of temperature measurement in critical care, temporal artery thermometry and an established method of core temperature measurement, bladder thermometry as performed in clinical practice.Methods
Temperatures were simultaneously recorded hourly (n = 736 observations) using both devices as part of routine clinical monitoring in 14 critically ill adult patients with temperatures ranging ≥1°C prior to consent.Results
The mean difference between temporal artery and bladder temperatures measured was -0.44°C (95% confidence interval, -0.47°C to -0.41°C), with temporal artery readings lower than bladder temperatures. Agreement between the two devices was greatest for normothermia (36.0°C to < 38.3°C) (mean difference -0.35°C [95% confidence interval, -0.37°C to -0.33°C]). The temporal artery thermometer recorded higher temperatures during hypothermia (< 36°C) (mean difference 0.66°C [95% confidence interval, 0.53°C to 0.79°C]) and lower temperatures during hyperthermia (≥38.3°C) (mean difference -0.90°C [95% confidence interval, -0.99°C to -0.81°C]). The sensitivity for detecting fever (core temperature ≥38.3°C) using the temporal artery thermometer was 0.26 (95% confidence interval, 0.20 to 0.33), and the specificity was 0.99 (95% confidence interval, 0.98 to 0.99). The positive likelihood ratio for fever was 24.6 (95% confidence interval, 10.7 to 56.8); the negative likelihood ratio was 0.75 (95% confidence interval, 0.68 to 0.82).Conclusions
Temporal artery thermometry produces somewhat surprising disagreement with an established method of core temperature measurement and should not to be used in situations where body temperature needs to be measured with accuracy. 相似文献150.
Jennifer MP Woo Zhuofeng Lin Mohamad Navab Casey Van Dyck Yvette Trejo-Lopez Krystal MT Woo Hongyun Li Lawrence W Castellani Xuping Wang Noriko Iikuni Ornella J Rullo Hui Wu Antonio La Cava Alan M Fogelman Aldons J Lusis Betty P Tsao 《Arthritis research & therapy》2010,12(3):R93