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51.
Rebecca A. Fletcher Rachel K. Brooks Vasiliy T. Lakoba Gourav Sharma Ariel R. Heminger Christopher C. Dickinson Jacob N. Barney 《Global Change Biology》2019,25(11):3694-3705
Despite our growing understanding of the impacts of invasive plants on ecosystem structure and function, important gaps remain, including whether native and exotic species respond differently to plant invasion. This would elucidate basic ecological interactions and inform management. We performed a meta‐analytic review of the effects of invasive plants on native and exotic resident animals. We found that invasive plants reduced the abundance of native, but not exotic, animals. This varied by animal phyla, with invasive plants reducing the abundance of native annelids and chordates, but not mollusks or arthropods. We found dissimilar impacts among “wet” and “dry” ecosystems, but not among animal trophic levels. Additionally, the impact of invasive plants increased over time, but this did not vary with animal nativity. Our review found that no studies considered resident nativity differences, and most did not identify animals to species. We call for more rigorous studies of invaded community impacts across taxa, and most importantly, explicit consideration of resident biogeographic origin. We provide an important first insight into how native and exotic species respond differently to invasion, the consequences of which may facilitate cascading trophic disruptions further exacerbating global change consequences to ecosystem structure and function. 相似文献
52.
Hey S Mayerhofer H Halford NG Dickinson JR 《The Journal of biological chemistry》2007,282(14):10472-10479
Sucrose nonfermenting-1 (Snf1)-related protein kinase-1 (SnRK1) of plants is a global regulator of carbon metabolism through the modulation of enzyme activity and gene expression. It is structurally and functionally related to the yeast protein kinase, Snf1, and to mammalian AMP-activated protein kinase. Two DNA sequences from Arabidopsis thaliana, previously known only by their data base accession numbers of NM_ 125448.3 (protein ID NP_200863) and NM_114393.3 (protein ID NP_566876) each functionally complemented a Saccharomyces cerevisiae elm1 sak1 tos3 triple mutant. This indicates that the Arabidopsis proteins are able to substitute for one of the missing yeast upstream kinases, which are required for activity of Snf1. Both plant proteins were shown to phosphorylate a peptide with the amino acid sequence of the phosphorylation site in the T-loop of SnRK1 and by inference SnRK1 in Arabidopsis. The proteins encoded by NM_125448.3 and NM_114393.3 have been named AtSnAK1 and AtSnAK2 (Arabidopsis thaliana SnRK1-activating kinase), respectively. We believe this is the first time that upstream activators of SnRK1 have been described in any plant species. 相似文献
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Ian A. Kent Qiao Zhang Aditya Katiyar Yuan Li Shreya Pathak Richard B. Dickinson Tanmay P. Lele 《Journal of cellular physiology》2019,234(11):20675-20684
Breast cancer nuclei have highly irregular shapes, which are diagnostic and prognostic markers of breast cancer progression. The mechanisms by which irregular cancer nuclear shapes develop are not well understood. Here we report the existence of vertical, apical cell protrusions in cultured MDA-MB-231 breast cancer cells. Once formed, these protrusions persist over time scales of hours and are associated with vertically upward nuclear deformations. They are absent in normal mammary epithelial cells (MCF-10A cells). Microtubule disruption enriched these protrusions preferentially in MDA-MB-231 cells compared with MCF-10A cells, whereas inhibition of nonmuscle myosin II (NMMII) abolished this enrichment. Dynamic confocal imaging of the vertical cell and nuclear shape revealed that the apical cell protrusions form first, and in response, the nucleus deforms and/or subsequently gets vertically extruded into the apical protrusion. Overexpression of lamin A/C in MDA-MB-231 cells reduced nuclear deformation in apical protrusions. These data highlight the role of mechanical stresses generated by moving boundaries, as well as abnormal nuclear mechanics in the development of abnormal nuclear shapes in breast cancer cells. 相似文献
55.
Margaret Campbell Naomi van der Linden Karen Gardner Helen Dickinson Jason Agostino Michelle Dowden Irene OMeara Meg Scolyer Hannah Woerle Rosalie Viney Kees van Gool 《PLoS neglected tropical diseases》2022,16(3)
BackgroundCrusted scabies is a debilitating dermatological condition. Although still relatively rare in the urban areas of Australia, rates of crusted scabies in remote Aboriginal communities in the Northern Territory (NT) are reported to be among the highest in the world.ObjectiveTo estimate the health system costs associated with diagnosing, treating and managing crusted scabies.MethodsA disease pathway model was developed to identify the major phases of managing crusted scabies. In recognition of the higher resource use required to treat more severe cases, the pathway differentiates between crusted scabies severity grades. The disease pathway model was populated with data from a clinical audit of 42 crusted scabies patients diagnosed in the Top-End of Australia’s Northern Territory between July 1, 2016 and May 1, 2018. These data were combined with standard Australian unit costs to calculate the expected costs per patient over a 12-month period, as well as the overall population cost for treating crusted scabies.FindingsThe expected health care cost per patient diagnosed with crusted scabies is $35,418 Australian dollars (AUD) (95% CI: $27,000 to $43,800), resulting in an overall cost of $1,558,392AUD (95% CI: $1,188,000 to $1,927,200) for managing all patients diagnosed in the Northern Territory in a given year (2018). By far, the biggest component of the health care costs falls on the hospital system.DiscussionThis is the first cost-of-illness analysis for treating crusted scabies. Such analysis will be of value to policy makers and researchers by informing future evaluations of crusted scabies prevention programs and resource allocation decisions. Further research is needed on the wider costs of crusted scabies including non-financial impacts such as the loss in quality of life as well as the burden of care and loss of well-being for patients, families and communities. 相似文献
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We investigated the motivational control of caching behaviour in scrub jays using a two-stage procedure to examine the effects of prefeeding and/or precaching (stage 1) on subsequent caching behaviour (stage 2). Experiment 1 demonstrated that both prefeeding and precaching reduced the subsequent caching of both edible (peanuts) and inedible (stones) items. The reduction in caching was greatest when the items available for storing were the same in the two stages. This item specificity was confirmed in experiment 2 using two food types, peanuts and dog food kibbles. The final experiment demonstrated that the effect of prefeeding on subsequent caching can also be food specific, in that birds that received food in a powdered form that they could eat, but not cache in stage 1, showed a reduction in subsequent caching in stage 2 only when the food type was the same in the two stages. These results suggest that caching behaviour is controlled by both the feeding system and an independent caching system, and that this control is mediated by the incentive value of the specific items rather than by a general motivational state. Copyright 1999 The Association for the Study of Animal Behaviour. 相似文献
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59.
Isoamyl alcohol-induced morphological change in Saccharomyces cerevisiae involves increases in mitochondria and cell wall chitin content 总被引:2,自引:0,他引:2
Isoamyl alcohol reduced growth and induced filament formation in Saccharomyces cerevisiae. Isoamyl alcohol-induced filamentation was accompanied by an almost threefold greater increase in the specific activity of succinate dehydrogenase than in untreated cells, which suggested that isoamyl alcohol treatment caused the cells to produce more mitochondria than in normal yeast form proliferation. This was supported by measuring the dry weight of purified, isolated mitochondria. Filaments have an increased chitin content which is distributed over the majority of their surface, and is not confined to bud scars and the chitin ring between mother and daughter cells as in yeast-form cells. 相似文献
60.
Marrison LR Dickinson JM Fairlamb IJ 《Bioorganic & medicinal chemistry letters》2003,13(16):2667-2671
Suzuki cross-coupling has been used to access a wide range of 3- and 5-substituted 2-pyrones, which show remarkable inhibitory activity against bacteria, yeasts and fungi. 3-Octenyl and 5-octenyl 2-pyrones inhibit human ovarium carcinoma (A2780) and human chronic myelogenous leukaemia (K562) cell lines at the micromolar level. 相似文献