| 1. |
- Feng, Shaohong, et al.
(författare)
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Dense sampling of bird diversity increases power of comparative genomics
- 2020
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 587:7833
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Tidskriftsartikel (refereegranskat)abstract
- Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity(1-4). Sparse taxon sampling has previously been proposed to confound phylogenetic inference(5), and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363 genomes from 92.4% of bird families-including 267 newly sequenced genomes produced for phase II of the Bird 10,000 Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species. A dataset of the genomes of 363 species from the Bird 10,000 Genomes Project shows increased power to detect shared and lineage-specific variation, demonstrating the importance of phylogenetically diverse taxon sampling in whole-genome sequencing.
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| 2. |
- Lawler, Mark, et al.
(författare)
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A Catalyst for Change: The European Cancer Patient's Bill of Rights.
- 2014
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Ingår i: The Oncologist. - : Oxford University Press (OUP). - 1549-490X .- 1083-7159.
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Tidskriftsartikel (refereegranskat)abstract
- The European Cancer Concord is a unique patient-centered partnership that will act as a catalyst to achieve improved access to an optimal standard of cancer care and research for European citizens. In order to provide tangible benefits for European cancer patients, the partnership proposes the creation of a “European Cancer Patient's Bill of Rights,” a patient charter that will underpin equitable access to an optimal standard of care for Europe's citizens.
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| 3. |
- Nyandoro, Stephen S., 1975, et al.
(författare)
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N-Cinnamoyltetraketide Derivatives from the Leaves of Toussaintia orientalis
- 2015
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Ingår i: Journal of natural products. - : American Chemical Society (ACS). - 0163-3864 .- 1520-6025. ; 78:8, s. 2045-2050
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Tidskriftsartikel (refereegranskat)abstract
- Seven N-cinnamoyltetraketides (1–7), including the new Z-toussaintine E (2), toussaintine F (6), and toussaintine G (7), were isolated from the methanol extract of the leaves of Toussaintia orientalis using column chromatography and HPLC. The configurations of E-toussaintine E (1) and toussaintines A (3) and D (5) are revised based on single-crystal X-ray diffraction data from racemic crystals. Both the crude methanol extract and the isolated constituents exhibit antimycobacterial activities (MIC 83.3–107.7 μM) against the H37Rv strain of Mycobacterium tuberculosis. Compounds 1, 3, 4, and 5 are cytotoxic (ED50 15.3–105.7 μM) against the MDA-MB-231 triple negative aggressive breast cancer cell line.
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| 4. |
- Aronsson, Per, et al.
(författare)
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Phytoconstituents with Radical Scavenging and Cytotoxic Activities from Diospyros shimbaensis.
- 2016
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Ingår i: Diseases (Basel, Switzerland). - : MDPI AG. - 2079-9721. ; 4:1
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Tidskriftsartikel (refereegranskat)abstract
- As part of our search for natural products having antioxidant and anticancer properties, the phytochemical investigation of Diospyros shimbaensis (Ebenaceae), a plant belonging to a genus widely used in East African traditional medicine, was carried out. From its stem and root barks the new naphthoquinone 8,8'-oxo-biplumbagin (1) was isolated along with the known tetralones trans-isoshinanolone (2) and cis-isoshinanolone (3), and the naphthoquinones plumbagin (4) and 3,3'-biplumbagin (5). Compounds 2, 4, and 5 showed cytotoxicity (IC50 520-82.1 μM) against MDA-MB-231 breast cancer cells. Moderate to low cytotoxicity was observed for the hexane, dichloromethane, and methanol extracts of the root bark (IC50 16.1, 29.7 and > 100 μg/mL, respectively), and for the methanol extract of the stem bark (IC50 59.6 μg/mL). The radical scavenging activity of the isolated constituents (1-5) was evaluated on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The applicability of the crude extracts and of the isolated constituents for controlling degenerative diseases is discussed.
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| 5. |
- Nyandoro, Stephen S., 1975, et al.
(författare)
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Flavonoids from Erythrina schliebenii
- 2017
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Ingår i: Journal of Natural Products. - : American Chemical Society (ACS). - 0163-3864 .- 1520-6025. ; 80:2, s. 377-383
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Tidskriftsartikel (refereegranskat)abstract
- Prenylated and O-methylflavonoids including one new pterocarpan (1), three new isoflavones (2-4), and nineteen known natural products (5-23) were isolated and identified from the root, stem bark, and leaf extracts of Erythrina schliebenii. The crude extracts and their constituents were evaluated for antitubercular activity against Mycobacterium tuberculosis (H37Rv strain), showing MICs of 32-64 mu g mL(-1) and 36.9-101.8 mu M, respectively. Evaluation of their toxicity against the aggressive human breast cancer cell line MDA-MB-231 indicated EC50 values of 13.0-290.6 mu M (pure compounds) and 38.3 to >100 mu g mL(-1) (crude extracts). RAMSON D, 1973, PHYTOCHEMISTRY, V12, P2211
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| 6. |
- Nyandoro, Stephen S., 1975, et al.
(författare)
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Polyoxygenated Cyclohexenes and Other Constituents of Cleistochlamys kirkii Leaves
- 2017
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Ingår i: Journal of natural products. - : American Chemical Society (ACS). - 0163-3864 .- 1520-6025. ; 80:1, s. 114-125
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Tidskriftsartikel (refereegranskat)abstract
- Thirteen new metabolites, including the polyoxygenated cyclohexene derivatives cleistodiendiol (1), cleistodienol B (3), cleistenechlorohydrins A (4) and B (5), cleistenediols A–F (6–11), cleistenonal (12), and the butenolide cleistanolate (13), 2,5-dihydroxybenzyl benzoate (cleistophenolide, 14), and eight known compounds (2, 15–21) were isolated from a MeOH extract of the leaves of Cleistochlamys kirkii. The purified metabolites were identified by NMR spectroscopic and mass spectrometric analyses, whereas the absolute configurations of compounds 1, 17, and 19 were established by single-crystal X-ray diffraction. The configuration of the exocyclic double bond of compound 2 was revised based on comparison of its NMR spectroscopic features and optical rotation to those of 1, for which the configuration was determined by X-ray diffraction. Observation of the co-occurrence of cyclohexenoids and heptenolides in C. kirkii is of biogenetic and chemotaxonomic significance. Some of the isolated compounds showed activity against Plasmodium falciparum (3D7, Dd2), with IC50 values of 0.2–40 μM, and against HEK293 mammalian cells (IC50 2.7–3.6 μM). While the crude extract was inactive at 100 μg/mL against the MDA-MB-231 triple-negative breast cancer cell line, some of its isolated constituents demonstrated cytotoxic activity with IC50 values ranging from 0.03–8.2 μM. Compound 1 showed the most potent antiplasmodial (IC50 0.2 μM) and cytotoxic (IC50 0.03 μM, MDA-MB-231 cell line) activities. None of the compounds investigated exhibited translational inhibitory activity in vitro at 20 μM.
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| 7. |
- Polyak, Leonid, et al.
(författare)
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History of sea ice in the Arctic
- 2010
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Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 29:15-16, s. 1757-1778
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Tidskriftsartikel (refereegranskat)abstract
- Arctic sea-ice extent and volume are declining rapidly. Several studies project that the Arctic Ocean may become seasonally ice-free by the year 2040 or even earlier. Putting this into perspective requires information on the history of Arctic sea-ice conditions through the geologic past. This information can be provided by proxy records from the Arctic Ocean floor and from the surrounding coasts. Although existing records are far from complete, they indicate that sea ice became a feature of the Arctic by 47 Ma, following a pronounced decline in atmospheric pCO(2) after the Paleocene-Eocene Thermal Optimum, and consistently covered at least part of the Arctic Ocean for no less than the last 13-14 million years. Ice was apparently most widespread during the last 2-3 million years, in accordance with Earth's overall cooler climate. Nevertheless, episodes of considerably reduced sea ice or even seasonally ice-free conditions occurred during warmer periods linked to orbital variations. The last low-ice event related to orbital forcing (high insolation) was in the early Holocene, after which the northern high latitudes cooled overall, with some superimposed shorterterm (multidecadal to millennial-scale) and lower-magnitude variability. The current reduction in Arctic ice cover started in the late 19th century, consistent with the rapidly warming climate, and became very pronounced over the last three decades. This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities.
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