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221.
Brown AR Bosies M Cameron H Clark J Cowley A Craighead M Elmore MA Firth A Goodwin R Goutcher S Grant E Grassie M Grove SJ Hamilton NM Hampson H Hillier A Ho KK Kiczun M Kingsbury C Kultgen SG Littlewood PT Lusher SJ Macdonald S McIntosh L McIntyre T Mistry A Morphy JR Nimz O Ohlmeyer M Pick J Rankovic Z Sherborne B Smith A Speake M Spinks G Thomson F Watson L Weston M 《Bioorganic & medicinal chemistry letters》2011,21(1):137-140
High-throughput screening of 3.87 million compounds delivered a novel series of non-steroidal GR antagonists. Subsequent rounds of optimisation allowed progression from a non-selective ligand with a poor ADMET profile to an orally bioavailable, selective, stable, glucocorticoid receptor antagonist. 相似文献
222.
Niall Conroy Susan Vlack Julian M. Williams John J. Patten Robert L. Horvath Stephen B. Lambert 《PLoS neglected tropical diseases》2013,7(2)
Background
Australia uses a protocol combining human rabies immunoglobulin (HRIG) and rabies vaccine for post-exposure prophylaxis (PEP) of rabies and Australian bat lyssavirus (ABLV), with the aim of achieving an antibody titre of ≥0.5 IU/ml, as per World Health Organization (WHO) guidelines, as soon as possible.Methodology/Principal Findings
We present the course of PEP administration and serological testing for four men with complex requirements. Following dog bites in Thailand, two men (62 years old, 25 years old) received no HRIG and had delayed vaccine courses: 23 days between dose two and three, and 18 days between dose one and two, respectively. Both seroconverted following dose four. Another 62-year-old male, who was HIV-positive (normal CD4 count), also suffered a dog bite and had delayed care receiving IM rabies vaccine on days six and nine in Thailand. Back in Australia, he received three single and one double dose IM vaccines followed by another double dose of vaccine, delivered intradermally and subcutaneously, before seroconverting. A 23-year-old male with a history of allergies received simultaneous HRIG and vaccine following potential ABLV exposure, and developed rash, facial oedema and throat tingling, which was treated with a parenteral antihistamine and tapering dose of steroids. Serology showed he seroconverted following dose four.Conclusions/Significance
These cases show that PEP can be complicated by exposures in tourist settings where reliable prophylaxis may not be available, where treatment is delayed or deviates from World Health Organization recommendations. Due to the potentially short incubation time of rabies/ABLV, timely prophylaxis after a potential exposure is needed to ensure a prompt and adequate immune response, particularly in patients who are immune-suppressed or who have not received HRIG. Serology should be used to confirm an adequate response to PEP when treatment is delayed or where a concurrent immunosuppressing medical condition or therapy exists. 相似文献223.
Pedro Afonso Niall McGinty Gon?alo Gra?a Jorge Fontes Mónica Inácio Atle Totland Gui Menezes 《PloS one》2014,9(5)
It has been speculated that some deep-sea fishes can display large vertical migrations and likely doing so to explore the full suite of benthopelagic food resources, especially the pelagic organisms of the deep scattering layer (DSL). This would help explain the success of fishes residing at seamounts and the increased biodiversity found in these features of the open ocean. We combined active plus passive acoustic telemetry of blackspot seabream with in situ environmental and biological (backscattering) data collection at a seamount to verify if its behaviour is dominated by vertical movements as a response to temporal changes in environmental conditions and pelagic prey availability. We found that seabream extensively migrate up and down the water column, that these patterns are cyclic both in short-term (tidal, diel) as well as long-term (seasonal) scales, and that they partially match the availability of potential DSL prey components. Furthermore, the emerging pattern points to a more complex spatial behaviour than previously anticipated, suggesting a seasonal switch in the diel behaviour mode (benthic vs. pelagic) of seabream, which may reflect an adaptation to differences in prey availability. This study is the first to document the fine scale three-dimensional behaviour of a deep-sea fish residing at seamounts. 相似文献
224.
Lower urinary tract trauma, although relatively uncommon in blunt trauma, can lead to significant morbidity when diagnosed late or left untreated; urologists may only encounter a handful of these injuries in their career. This article reviews the literature and reports on the management of these injuries, highlighting the issues facing clinicians in this subspecialty. Also presented is a structured review detailing the mechanisms, classification, diagnosis, management, and complications of blunt trauma to the bladder and urethra. The prognosis for bladder rupture is excellent when treated. Significant intraperitoneal rupture or involvement of the bladder neck mandates surgical repair, whereas smaller extraperitoneal lacerations may be managed with catheterization alone. With the push for management of trauma patients in larger centers, urologists in these hospitals are seeing increasing numbers of lower urinary tract injuries. Prospective analysis may be achieved in these centers to address the current lack of Level 1 evidence. 相似文献
225.
The activities of many mammalian membrane proteins including G-protein coupled receptors are cholesterol-dependent. Unlike higher eukaryotes, yeast do not make cholesterol. Rather they make a related molecule called ergosterol. As cholesterol and ergosterol are biologically non-equivalent, the potential of yeast as hosts for overproducing mammalian membrane proteins has never been fully realised. To address this problem, we are trying to engineer a novel strain of Saccharomyces cerevisiae in which the cholesterol biosynthetic pathway of mammalian cells has been fully reconstituted. Thus far, we have created a modified strain that makes cholesterol-like sterols which has an increased capacity to make G-protein coupled receptors compared to control yeast. 相似文献
226.
There is considerable interest in cell biology in determining whether, and to what extent, the spatial arrangement of nuclear objects affects nuclear function. A common approach to address this issue involves analyzing a collection of images produced using some form of fluorescence microscopy. We assume that these images have been successfully pre-processed and a spatial point pattern representation of the objects of interest within the nuclear boundary is available. Typically in these scenarios, the number of objects per nucleus is low, which has consequences on the ability of standard analysis procedures to demonstrate the existence of spatial preference in the pattern. There are broadly two common approaches to look for structure in these spatial point patterns. First a spatial point pattern for each image is analyzed individually, or second a simple normalization is performed and the patterns are aggregated. In this paper we demonstrate using synthetic spatial point patterns drawn from predefined point processes how difficult it is to distinguish a pattern from complete spatial randomness using these techniques and hence how easy it is to miss interesting spatial preferences in the arrangement of nuclear objects. The impact of this problem is also illustrated on data related to the configuration of PML nuclear bodies in mammalian fibroblast cells. 相似文献
227.
Nyström V Humphrey J Skoglund P McKeown NJ Vartanyan S Shaw PW Lidén K Jakobsson M Barnes I Angerbjörn A Lister A Dalén L 《Molecular ecology》2012,21(14):3391-3402
The last glaciation was a dynamic period with strong impact on the demography of many species and populations. In recent years, mitochondrial DNA sequences retrieved from radiocarbon-dated remains have provided novel insights into the history of Late Pleistocene populations. However, genotyping of loci from the nuclear genome may provide enhanced resolution of population-level changes. Here, we use four autosomal microsatellite DNA markers to investigate the demographic history of woolly mammoths (Mammuthus primigenius) in north-eastern Siberia from before 60 000 years ago up until the species' final disappearance c.4000 years ago. We identified two genetic groups, implying a marked temporal genetic differentiation between samples with radiocarbon ages older than 12 thousand radiocarbon years before present (ka) and those younger than 9ka. Simulation-based analysis indicates that this dramatic change in genetic composition, which included a decrease in individual heterozygosity of approximately 30%, was due to a multifold reduction in effective population size. A corresponding reduction in genetic variation was also detected in the mitochondrial DNA, where about 65% of the diversity was lost. We observed no further loss in genetic variation during the Holocene, which suggests a rapid final extinction event. 相似文献
228.
Thermal optimality of net ecosystem exchange of carbon dioxide and underlying mechanisms 总被引:1,自引:0,他引:1
Niu S Luo Y Fei S Yuan W Schimel D Law BE Ammann C Arain MA Arneth A Aubinet M Barr A Beringer J Bernhofer C Black TA Buchmann N Cescatti A Chen J Davis KJ Dellwik E Desai AR Etzold S Francois L Gianelle D Gielen B Goldstein A Groenendijk M Gu L Hanan N Helfter C Hirano T Hollinger DY Jones MB Kiely G Kolb TE Kutsch WL Lafleur P Lawrence DM Li L Lindroth A Litvak M Loustau D Lund M Marek M Martin TA Matteucci G Migliavacca M Montagnani L Moors E Munger JW Noormets A Oechel W Olejnik J 《The New phytologist》2012,194(3):775-783
? It is well established that individual organisms can acclimate and adapt to temperature to optimize their functioning. However, thermal optimization of ecosystems, as an assemblage of organisms, has not been examined at broad spatial and temporal scales. ? Here, we compiled data from 169 globally distributed sites of eddy covariance and quantified the temperature response functions of net ecosystem exchange (NEE), an ecosystem-level property, to determine whether NEE shows thermal optimality and to explore the underlying mechanisms. ? We found that the temperature response of NEE followed a peak curve, with the optimum temperature (corresponding to the maximum magnitude of NEE) being positively correlated with annual mean temperature over years and across sites. Shifts of the optimum temperature of NEE were mostly a result of temperature acclimation of gross primary productivity (upward shift of optimum temperature) rather than changes in the temperature sensitivity of ecosystem respiration. ? Ecosystem-level thermal optimality is a newly revealed ecosystem property, presumably reflecting associated evolutionary adaptation of organisms within ecosystems, and has the potential to significantly regulate ecosystem-climate change feedbacks. The thermal optimality of NEE has implications for understanding fundamental properties of ecosystems in changing environments and benchmarking global models. 相似文献
229.
To investigate the role of experience in humans’ perception of emotion using canine visual signals, we asked adults with various levels of dog experience to interpret the emotions of dogs displayed in videos. The video stimuli had been pre-categorized by an expert panel of dog behavior professionals as showing examples of happy or fearful dog behavior. In a sample of 2,163 participants, the level of dog experience strongly predicted identification of fearful, but not of happy, emotional examples. The probability of selecting the “fearful” category to describe fearful examples increased with experience and ranged from.30 among those who had never lived with a dog to greater than.70 among dog professionals. In contrast, the probability of selecting the “happy” category to describe happy emotional examples varied little by experience, ranging from.90 to.93. In addition, the number of physical features of the dog that participants reported using for emotional interpretations increased with experience, and in particular, more-experienced respondents were more likely to attend to the ears. Lastly, more-experienced respondents provided lower difficulty and higher accuracy self-ratings than less-experienced respondents when interpreting both happy and fearful emotional examples. The human perception of emotion in other humans has previously been shown to be sensitive to individual differences in social experience, and the results of the current study extend the notion of experience-dependent processes from the intraspecific to the interspecific domain. 相似文献
230.
Karine Malagu Heather Duggan Keith Menear Marc Hummersone Sylvie Gomez Christine Bailey Peter Edwards Jan Drzewiecki Frédéric Leroux Mar Jimenez Quesada Gesine Hermann Stephanie Maine Carrie-Anne Molyneaux Armelle Le Gall James Pullen Ian Hickson Lisa Smith Sharon Maguire Niall Martin Graeme Smith Martin Pass 《Bioorganic & medicinal chemistry letters》2009,19(20):5950-5953
We describe a novel series of potent inhibitors of the kinase activity of mTOR. The compounds display good selectivity relative to other PI3K-related kinase family members and, in cellular assays, inhibit both mTORC1 and mTORC2 complexes and exhibit good antiproliferative activity. 相似文献