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971.
972.
Bonnie Williams Florence Lees Helen Tsangari Mark R. Hutchinson Egon Perilli Tania N. Crotti 《The journal of histochemistry and cytochemistry》2021,69(8):511
Induction of severe inflammatory arthritis in the collagen antibody-induced arthritis (CAIA) murine model causes extensive joint damage and pain-like behavior compromising analysis. While mild models are less severe, their reduced, variable penetrance makes assessment of treatment efficacy difficult. This study aimed to compare macroscopic and microscopic changes in the paws, along with central nervous system activation between a mild and moderate CAIA model. Balb/c mice (n=18) were allocated to control, mild, and moderate CAIA groups. Paw inflammation, bone volume (BV), and paw volume (PV) were assessed. Histologically, the front paws were assessed for joint inflammation, cartilage damage, and pre/osteoclast-like cells and the lumbar spinal cord and the periaqueductal gray (PAG) region of the brain for glial reactivity. A moderate CAIA dose induced (1) significantly greater local paw inflammation, inflammatory cell infiltration, and PV; (2) significantly more osteoclast-like cells on the bone surface and within the surrounding soft tissue; and (3) significantly greater glial reactivity within the PAG compared with the mild CAIA model. These findings support the use of a moderate CAIA model (higher dose of monoclonal antibodies with low-dose lipopolysaccharide) to induce more consistent histopathological features, without excessive joint destruction. 相似文献
973.
S.T. Aspinall D.R.A. Wareing P.G. Hayward D.N. Hutchinson 《Journal of applied microbiology》1996,80(6):645-650
The newly developed CAT campylobacter selective medium employing the blood-free charcoal-based agar containing cefoperazone (8 mg I−1 ), amphotericin (10 mg I−1 ) and teicoplanin (4 mg I−1 ) was compared with the membrane filtration culture technique for isolation of Campylobacter spp. including Camp. upsaliensis. Nine hundred and fifty human, 275 dog and 65 cat faeces (in which modified CCDA medium was also compared) were tested. In addition, the recovery of Camp. upsaliensis from pure cultures and from spiked human faeces was examined after membrane filtration. A 50-fold reduction in recovery after filtration using the 0·65 μm filters and a 150-fold reduction using the 0·45 μm filters was found. Recovery of Camp. upsaliensis from spiked faeces was considerably improved using the CAT medium compared with filtration, especially with the lower concentration of organisms (approx. 104 cfu ml−1 ). Campylobacter upsaliensis was recovered from 91 specimens of animal faeces, with CCDA recovering 26 isolates (29%), CAT recovering 76 isolates (84%) and membrane filtration (0·65 μm) recovering 82 isolates (90%). CAT selective agar was found to be a suitable medium for the isolation of thermophilic campylobacters including Camp. upsaliensis from faecal samples. 相似文献
974.
Janet E. Squires Leslie Hayduk Alison M. Hutchinson Ranjeeta Mallick Peter G. Norton Greta G. Cummings Carole A. Estabrooks 《PloS one》2015,10(6)
Although organizational context is central to evidence-based practice, underdeveloped measurement hindersitsassessment. The Alberta Context Tool, comprised of 59 items that tap10 modifiable contextual concepts, was developed to address this gap. The purpose of this study to examine the reliability and validity of scores obtained when the Alberta Context Tool is completed by professional nurses across different healthcare settings. Five separate studies (N = 2361 nurses across different care settings) comprised the study sample. Reliability and validity were assessed. Cronbach’s alpha exceeded 0.70 for9/10 Alberta Context Tool concepts. Item-total correlations exceeded acceptable standards for 56/59items. Confirmatory Factor Analysescoordinated acceptably with the Alberta Context Tool’s proposed latent structure. The mean values for each Alberta Context Tool concept increased from low to high levels of research utilization(as hypothesized) further supporting its validity. This study provides robust evidence forreliability and validity of scores obtained with the Alberta Context Tool when administered to professional nurses. 相似文献
975.
The discovery of a rapidly metabolized polymeric tetraphosphate derivative of adenosine in perfused rat heart. 下载免费PDF全文
The predicted presence in perfused rat hearts of a rapidly metabolized but hitherto unrecognized form of adenosine phosphate has been confirmed by specific radioactive labelling. The properties of the purified compound suggest that it is a heteropolymer of a small organic acid, phosphate and purine nucleoside in the proportions 1:4:1. 相似文献
976.
Bees provide critical pollination services to 87% of angiosperm plants; however, the reliability of these services may become threatened as bee populations decline. Agricultural intensification, resulting in the simplification of environments at the landscape scale, greatly changes the quality and quantity of resources available for female bees to provision their offspring. These changes may alter or constrain the tradeoffs in maternal investment allocation between offspring size, number and sex required to maximize fitness. Here we investigate the relationship between landscape scale agricultural intensification and the size and number of individuals within a wild ground nesting bee species, Andrena nasonii. We show that agricultural intensification at the landscape scale was associated with a reduction in the average size of field collected A. nasonii adults in highly agricultural landscapes but not with the number of individuals collected. Small females carried significantly smaller (40%) pollen loads than large females, which is likely to have consequences for subsequent offspring production and fitness. Thus, landscape simplification is likely to constrain allocation of resources to offspring through a reduction in the overall quantity, quality and distribution of resources. 相似文献
977.
Claire E. Treilibs Chris R. Pavey Mark N. Hutchinson C. Michael Bull 《Ecology and evolution》2016,6(3):800-809
Recognition of individuals within an animal population is central to a range of estimates about population structure and dynamics. However, traditional methods of distinguishing individuals, by some form of physical marking, often rely on capture and handling which may affect aspects of normal behavior. Photographic identification has been used as a less‐invasive alternative, but limitations in both manual and computer‐automated recognition of individuals are particularly problematic for smaller taxa (<500 g). In this study, we explored the use of photographic identification for individuals of a free‐ranging, small terrestrial reptile using (a) independent observers, and (b) automated matching with the Interactive Individual Identification System (I3S Pattern) computer algorithm. We tested the technique on individuals of an Australian skink in the Egernia group, Slater's skink Liopholis slateri, whose natural history and varied scale markings make it a potentially suitable candidate for photo‐identification. From ‘photographic captures’ of skink head profiles, we designed a multi‐choice key based on alternate character states and tested the abilities of observers — with or without experience in wildlife survey — to identify individuals using categorized test photos. We also used the I3S Pattern algorithm to match the same set of test photos against a database of 30 individuals. Experienced observers identified a significantly higher proportion of photos correctly (74%) than those with no experience (63%) while the I3S software correctly matched 67% as the first ranked match and 83% of images in the top five ranks. This study is one of the first to investigate photo identification with a free‐ranging small vertebrate. The method demonstrated here has the potential to be applied to the developing field of camera‐traps for wildlife survey and thus a wide range of survey and monitoring applications. 相似文献
978.
Lauren Turrell Edward C. Hutchinson Frank T. Vreede Ervin Fodor 《Journal of virology》2015,89(2):1452-1455
In the influenza virus ribonucleoprotein complex, the oligomerization of the nucleoprotein is mediated by an interaction between the tail-loop of one molecule and the groove of the neighboring molecule. In this study, we show that phosphorylation of a serine residue (S165) within the groove of influenza A virus nucleoprotein inhibits oligomerization and, consequently, ribonucleoprotein activity and viral growth. We propose that nucleoprotein oligomerization in infected cells is regulated by reversible phosphorylation. 相似文献
979.
J. B. Hutchinson 《Journal of genetics》1940,40(1-2):271-282
980.
Isolation and characterization of polyoma virus genomes with deletions between the origin of viral DNA replication and the site of initiation of translation in the early region. 下载免费PDF全文
We introduced deletions in the early region of the polyoma virus genome near the HaeII restriction enzyme cleavage site, between the origin of viral DNA replication and the site of initiation of translation of the polyoma T antigens. We analyzed the DNA of the deletion mutants by restriction enzyme digestion. Four of the mutants had deletions beginning very close to the HaeII site and extending clockwise toward the site of initiation of translation. The deletions near the HaeII site varied in size from about 10 base pairs to about 55 base pairs. The mutants containing deletions near the HaeII site were capable of lytic growth in mouse 3T6 cells and were capable of transforming rat F2408 cells, as judged by focus formation. 相似文献