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21.
Stephen C. Votier Anthony Bicknell Samantha L. Cox Kylie L. Scales Samantha C. Patrick 《PloS one》2013,8(3)
Commercial capture fisheries produce huge quantities of offal, as well as undersized and unwanted catch in the form of discards. Declines in global catches and legislation to ban discarding will significantly reduce discards, but this subsidy supports a large scavenger community. Understanding the potential impact of declining discards for scavengers should feature in an eco-system based approach to fisheries management, but requires greater knowledge of scavenger/fishery interactions. Here we use bird-borne cameras, in tandem with GPS loggers, to provide a unique view of seabird/fishery interactions. 20,643 digital images (one min−1) from ten bird-borne cameras deployed on central place northern gannets Morus bassanus revealed that all birds photographed fishing vessels. These were large (>15 m) boats, with no small-scale vessels. Virtually all vessels were trawlers, and gannets were almost always accompanied by other scavenging birds. All individuals exhibited an Area-Restricted Search (ARS) during foraging, but only 42% of ARS were associated with fishing vessels, indicating much ‘natural’ foraging. The proportion of ARS behaviours associated with fishing boats were higher for males (81%) than females (30%), although the reasons for this are currently unclear. Our study illustrates that fisheries form a very important component of the prey-landscape for foraging gannets and that a discard ban, such as that proposed under reforms of the EU Common Fisheries Policy, may have a significant impact on gannet behaviour, particularly males. However, a continued reliance on ‘natural’ foraging suggests the ability to switch away from scavenging, but only if there is sufficient food to meet their needs in the absence of a discard subsidy. 相似文献
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Davide Danovi Amos Folarin Sabine Gogolok Christine Ender Ahmed M. O. Elbatsh P?r G. Engstr?m Stefan H. Stricker Sladjana Gagrica Ana Georgian Ding Yu Kin Pong U Kevin J. Harvey Patrizia Ferretti Patrick J. Paddison Jane E. Preston N. Joan Abbott Paul Bertone Austin Smith Steven M. Pollard 《PloS one》2013,8(10)
Glioblastoma multiforme (GBM) is the most common primary brain cancer in adults and there are few effective treatments. GBMs contain cells with molecular and cellular characteristics of neural stem cells that drive tumour growth. Here we compare responses of human glioblastoma-derived neural stem (GNS) cells and genetically normal neural stem (NS) cells to a panel of 160 small molecule kinase inhibitors. We used live-cell imaging and high content image analysis tools and identified JNJ-10198409 (J101) as an agent that induces mitotic arrest at prometaphase in GNS cells but not NS cells. Antibody microarrays and kinase profiling suggested that J101 responses are triggered by suppression of the active phosphorylated form of polo-like kinase 1 (Plk1) (phospho T210), with resultant spindle defects and arrest at prometaphase. We found that potent and specific Plk1 inhibitors already in clinical development (BI 2536, BI 6727 and GSK 461364) phenocopied J101 and were selective against GNS cells. Using a porcine brain endothelial cell blood-brain barrier model we also observed that these compounds exhibited greater blood-brain barrier permeability in vitro than J101. Our analysis of mouse mutant NS cells (INK4a/ARF−/−, or p53−/−), as well as the acute genetic deletion of p53 from a conditional p53 floxed NS cell line, suggests that the sensitivity of GNS cells to BI 2536 or J101 may be explained by the lack of a p53-mediated compensatory pathway. Together these data indicate that GBM stem cells are acutely susceptible to proliferative disruption by Plk1 inhibitors and that such agents may have immediate therapeutic value. 相似文献
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Frank Josef Mller Oliver Zierau Torsten Hertrampf Anja Bliedtner Patrick Diel Günter Vollmer 《The Journal of steroid biochemistry and molecular biology》2009,113(3-5):296-303
Isoflavones (ISOs) are bioactive food ingredients of the traditional East Asian diet and currently discussed as alternatives to classical hormone replacement therapies and for reducing the prevalence of hormone-dependent cancers. Although there are many studies on ISOs, not much is known about their long-term effects.Therefore, we performed an animal experiment analyzing the effects of three different diets: a phytoestrogen-free diet, a diet supplemented with genistein (700 μg/g diet) and an ISO-high diet (232 μg daidzein and 240 μg genistein/g) at two distinct time points, juvenile (21 days) and adult (97 days). Exposure started prior to mating of the parents and throughout the life of the offspring.We observed a stronger increase of uterine wet weights in juvenile offspring with genistein exposure (1018 ± 350 mg/kg BW) than with ISO-high diet (497 ± 133 mg/kg BW). Whereas the expression of proliferation related genes (PCNA; Ki67; IGF-1; IGF-1R), analyzed by real-time-qPCR and Western blot, were significantly down-regulated in juvenile animals exposed to genistein. Additionally, genistein exposure led to estrogenic responses, observed upon increase of complement C3 and decrease of estrogen receptors gene expressions, while the exposure to ISO-high diet did not show these effects.In conclusion, both the time point on which phytoestrogen exposure starts together with the composition of the ingested phytoestrogen containing diet are of great importance for the biological response of the offspring. 相似文献
26.
J.F. Kuo Eugene J. Malveaux Janice G. Patrick Craig W. Davis Albert W. Pruitt 《Biochimica et Biophysica Acta (BBA)/General Subjects》1977,497(3):785-796
Possible involvement of cyclic GMP-dependent and cyclic AMP-dependent protein kinases, protein kinase modulators and cyclic nucleotide phosphodiesterases in functions of vascular tissues were investigated in the dog. All of the above activities, localized in the smooth muscle-rich inner layer of the blood vessels, were found to be higher in the arteries than in the veins. The peripheral arteries were disproportionately richer in cyclic GMP-dependent protein kinase (as indicated by high ratios of cyclic GMP-dependent to cyclic AMP-dependent protein kinase) than were the veins, with the exception of the pulmonary artery, an atypical arterial tissue exposed to low blood pressure. Interestingly, the protein kinase ratio for the aorta, an artery with no significant role in blood pressure regulation, was not higher than that for the vena cava. Creation of femoral arteriovenous fistulae in the dogs led to preferential reductions in the cyclic GMP-dependent enzyme activity both in the proximal and distal arteries, whereas it was elevated in the stressed vein distal to the anastomotic site. The cyclic GMP-dependent enzyme was preferentially reduced in the saphenous artery distal to occlusion. Changes in the cyclic GMP-dependent enzyme activity appeared to precede gross atrophy or hypertrophy of the vessels. It is suggested that the vascular cyclic GMP-dependent protein kinase may be closely related to peripheral resistance and its regulation. 相似文献
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Synopsis Young-of-the-year largemouth bass,Micropterus salmoides, were exposed to four concentrations of sulphuric acid (pH levels 7.2, 6.1, 4.8, and 3.7) for 30 days, and the frequencies of feeding acts and activity bouts, and time budgets were recorded. Juveniles at pH 6.1 and at pH 4.8 performed the two feeding acts, bites and orientations, more often, and spent more time feeding than bass at pH 7.2. Bass at pH 3.7, however, reduced feeding, and spent a significantly larger portion of their time hovering in the water column. Frequencies of comfort and agonistic acts increased with a decline in pH. Alterations of behavioural repertoires of young-of-the-year largemouth bass were useful indicators of sulphuric acid exposure. 相似文献
30.
Patrick Sullivan 《CMAJ》1987,137(11):1040-1041