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61.
Elmén J Lindow M Silahtaroglu A Bak M Christensen M Lind-Thomsen A Hedtjärn M Hansen JB Hansen HF Straarup EM McCullagh K Kearney P Kauppinen S 《Nucleic acids research》2008,36(4):1153-1162
MicroRNA-122 (miR-122) is an abundant liver-specific miRNA, implicated in fatty acid and cholesterol metabolism as well as hepatitis C viral replication. Here, we report that a systemically administered 16-nt, unconjugated LNA (locked nucleic acid)-antimiR oligonucleotide complementary to the 5′ end of miR-122 leads to specific, dose-dependent silencing of miR-122 and shows no hepatotoxicity in mice. Antagonism of miR-122 is due to formation of stable heteroduplexes between the LNA-antimiR and miR-122 as detected by northern analysis. Fluorescence in situ hybridization demonstrated uptake of the LNA-antimiR in mouse liver cells, which was accompanied by markedly reduced hybridization signals for mature miR-122 in treated mice. Functional antagonism of miR-122 was inferred from a low cholesterol phenotype and de-repression within 24 h of 199 liver mRNAs showing significant enrichment for miR-122 seed matches in their 3′ UTRs. Expression profiling extended to 3 weeks after the last LNA-antimiR dose revealed that most of the changes in liver gene expression were normalized to saline control levels coinciding with normalized miR-122 and plasma cholesterol levels. Combined, these data suggest that miRNA antagonists comprised of LNA are valuable tools for identifying miRNA targets in vivo and for studying the biological role of miRNAs and miRNA-associated gene-regulatory networks in a physiological context. 相似文献
62.
Morten Bo Johansen Jose M. G. Izarzugaza S?ren Brunak Thomas Nordahl Petersen Ramneek Gupta 《PloS one》2013,8(7)
We have developed a sequence conservation-based artificial neural network predictor called NetDiseaseSNP which classifies nsSNPs as disease-causing or neutral. Our method uses the excellent alignment generation algorithm of SIFT to identify related sequences and a combination of 31 features assessing sequence conservation and the predicted surface accessibility to produce a single score which can be used to rank nsSNPs based on their potential to cause disease. NetDiseaseSNP classifies successfully disease-causing and neutral mutations. In addition, we show that NetDiseaseSNP discriminates cancer driver and passenger mutations satisfactorily. Our method outperforms other state-of-the-art methods on several disease/neutral datasets as well as on cancer driver/passenger mutation datasets and can thus be used to pinpoint and prioritize plausible disease candidates among nsSNPs for further investigation. NetDiseaseSNP is publicly available as an online tool as well as a web service: http://www.cbs.dtu.dk/services/NetDiseaseSNP 相似文献
63.
Morten Frederiksen Tycho Anker‐Nilssen Grégory Beaugrand Sarah Wanless 《Global Change Biology》2013,19(2):364-372
The boreal Northeast Atlantic is strongly affected by current climate change, and large shifts in abundance and distribution of many organisms have been observed, including the dominant copepod Calanus finmarchicus, which supports the grazing food web and thus many fish populations. At the same time, large‐scale declines have been observed in many piscivorous seabirds, which depend on abundant small pelagic fish. Here, we combine predictions from a niche model of C. finmarchicus with long‐term data on seabird breeding success to link trophic levels. The niche model shows that environmental suitability for C. finmarchicus has declined in southern areas with large breeding seabird populations (e.g. the North Sea), and predicts that this decline is likely to spread northwards during the 21st century to affect populations in Iceland and the Faroes. In a North Sea colony, breeding success of three common piscivorous seabird species [black‐legged kittiwake (Rissa tridactyla), common guillemot (Uria aalge) and Atlantic puffin (Fratercula arctica)] was strongly positively correlated with local environmental suitability for C. finmarchicus, whereas this was not the case at a more northerly colony in west Norway. Large seabird populations seem only to occur where C. finmarchicus is abundant, and northward distributional shifts of common boreal seabirds are therefore expected over the coming decades. Whether or not population size can be maintained depends on the dispersal ability and inclination of these colonial breeders, and on the carrying capacity of more northerly areas in a warmer climate. 相似文献
64.
Johanna Hedlund Thord Fransson Cecilia Kullberg JanOlov Persson Sven Jakobsson 《Ecology and evolution》2022,12(7)
Protandry is a widespread life‐history phenomenon describing how males precede females at the site or state of reproduction. In migratory birds, protandry has an important influence on individual fitness, the migratory syndrome, and phenological response to climate change. Despite its significance, accurate analyses on the dynamics of protandry using data sets collected at the breeding site, are lacking. Basing our study on records collected during two time periods, 1979 to 1988 and 2006 to 2016, we aim to investigate protandry dynamics over 38 years in a breeding population of willow warblers (Phylloscopus trochilus). Change in the timing of arrival was analyzed in males and females, and protandry (number of days between male and female arrival) was investigated both at population level and within breeding pairs. Our results show advancement in the arrival time at the breeding site in both sexes, but male arrival has advanced to a greater extent, leading to an increase in protandry both at the population level and within breeding pairs. We did not observe any change in sex ratio that could explain the protandry increase, but pronounced temperature change has occurred and been reported in the breeding area and along the migratory route. Typically, natural selection opposes too early arrival in males, but given warmer springs, this counteracting force may be relaxing, enabling an increase in protandry. We discuss whether our results suggest that climate change has induced sex‐specific effects, if these could be evolutionary and whether the timing of important life‐history stages such as arrival at the breeding site may change at different rates in males and females following environmental shifts. 相似文献
65.
A human skull with mandible from the Ngada District on the island of Flores, Indonesia, is described in order to contribute to the knowledge of variation in cranial architecture, which is important in interpretations of evolutionary cerebralisation. The skull was excavated in 1924 and sent to the National Museum in Copenhagen. The “Copenhagen Flores” (CF) male skull is radiocarbon-dated and of modern age. The cranium is small, but larger than e.g. Liang Bua skull (LB1) in every measurement. The (CT-scan based) cranial capacity of 1258 ml is normal for modern humans, but somewhat lower than values from the middle or upper Palaeolithics. The metric cranial data analysed in FORDISC, characterize the skull as a male Vietnamese rather than a Chinese or White individual. Tooth morphology shows the sundadont pattern and tooth size corresponds to that of teeth from Bali, Java and Malayan Orang Asli. Remarkable are the marked asymmetries in the dentition with rotation of an upper premolar and congenital absence of a third molar. In these respects the CF skull is similar to dentitions belonging to the pygmoid villagers of Rampasasa, a village not far from the Liang Bua cave, and to LB1. 相似文献
66.
Lars-Eric Persson 《Journal of experimental marine biology and ecology》1983,68(3):277-293
Quantitative (0.1-m2) samples of benthic macrofauna were taken at three depths (5, 10, 17 m) off the eastern coast of Scania, southern Baltic, in the period April 1974 to August 1978. Altogether 20 sampling cruises were made. Spatial and temporal species composition, abundance and biomass were compared. The number of species increased significantly with increasing depth. Zonation of the species was due to their zoogeographical origin and capacity to withstand exposure. Abundance was highest at 5 m depth whereas biomass increased with depth due to the dominance of large bivalves. Variation in abundance within years was large at all three depths and connected with reproductive recruitment for all species except Bathyporeia pilosa Lindström which migrated towards the shore in summer. 相似文献
67.
The human aldose reductase gene maps to chromosome region 7q35 总被引:1,自引:0,他引:1
Alexander Graham Paul Heath John E. N. Morten Alexander F. Markham 《Human genetics》1991,86(5):509-514
Summary The human aldose reductase (AR) gene has been mapped to chromosome 7 using the polymerase chain reaction to specifically amplify the human AR sequence in hamster/human hybrid DNA and also in mouse/ human monochromosome hybrids. The assignment to chromosome 7 was confirmed by in situ hybridisation to human metaphase chromosomes using a novel, rapid hybridisation, method giving a regional localisation at 7q35. 相似文献
68.
Persson Joel Ford Scott Keophoxay Anousith Mertz Ole Nielsen Jonas Østergaard Vongvisouk Thoumthone Zörner Michael 《Human ecology: an interdisciplinary journal》2021,49(5):597-616
Human Ecology - Despite the popularity of integrated conservation and development approaches to protected area management, adjacent communities increasingly face livelihood dilemmas. Yet... 相似文献
69.
Bertil Persson Anders Andersson Björn Hultberg Christer Hansson 《Free radical research》2013,47(2):151-156
Glutathione, the most abundant low-molecular weight thiol in the skin, has been shown to protect the skin from both photobiological and chemical injury. The thiols, glutathione in particular, have also been shown to be crucially involved in defence against contact allergens. Since the levels of extracellular thiol concentrations are important determinants of intracellular thiol status, we have compared the normal concentrations and the redox status of the main low-molecular weight thiol components in the extracellular fluid at the dermo-epidermal junction with the corresponding plasma levels. In their sulfhydryl form, all three thiols, i.e. glutathione, cysteine and homocysteine, were more abundant in experimental skin blister fluid than in plasma, as were the free disulfides of glutathione and homocysteine, whereas the free disulfides of cysteine were about the same in blister fluid and in plasma. Protein mixed disulfide levels were higher in plasma than in blister fluid. The present results provide information concerning the extracellular defence in the skin. 相似文献
70.
Frederik Banch Clausen Tanja Roien Jakobsen Klaus Rieneck Grethe Risum Krog Leif Kofoed Nielsen Ann Tabor Morten Hanefeld Dziegiel 《PloS one》2013,8(10)