| 1. |
- Fan, B.-B., et al.
(författare)
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Dry/wet cycling reduces spore germination and viability in six peatland bryophytes
- 2023
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Ingår i: Plant Biology. - : German Society for Plant Sciences; Royal Botanical Society of the Netherlands. - 1435-8603 .- 1438-8677. ; 25:3, s. 440-447
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Tidskriftsartikel (refereegranskat)abstract
- Dry/wet cycling driven by water level fluctuation in wetlands may strongly influence the destiny of seeds. However, how dry/wet cycling affects spore survival and germinability in peatland bryophytes is poorly understood.Six peatland bryophytes, three hummock- and three hollow-dwelling Sphagnum species, were chosen as study species. We tested the effects of dry (60% air RH)/wet (waterlogging) cycle frequency (once per 12, 8 or 4 days for low, medium or high, respectively) and ratio (3:1, 1:1 or 1:3 dry:wet time per cycle) on spore germinability, viability, dormancy percentage and protonema development.Dry/wet cycling significantly reduced spore germination percentage and viability and slowed protonema development in all Sphagnum species, being more pronounced with higher dry/wet cycling frequencies. The hummock species S. capillifolium and S. fuscum had higher spore germination percentage after the continuous dry treatment, while the hollow species S. angustifolium, S. squarrosum and S. subsecundum showed the opposite response, compared to the continuously wet treatment. Except for S. squarrosum, spore viability was higher after the dry than after the wet treatment. Spore viability and dormancy percentage were higher after a dry/wet ratio of 1:3 than after ratios of 3:1 and 1:1.Our study shows that both germinability and viability of bryophyte spores are reduced by dry/wet cycling (especially when frequent) in peatlands. This emphasizes the need to ensure constant water levels and low frequencies of water level fluctuation, which are relevant in connection with wetland restoration, to promote Sphagnum spore survival and establishment in peatlands after disturbances.
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| 2. |
- Fan, C-W, et al.
(författare)
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Cancer-initiating cells derived from human rectal adenocarcinoma tissues carry mesenchymal phenotypes and resist drug therapies
- 2013
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Ingår i: Cell Death and Disease. - : Nature Publishing Group: Open Access Journals - Option B / Nature Publishing Group. - 2041-4889. ; 4, s. e828-
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Tidskriftsartikel (refereegranskat)abstract
- Accumulating evidence indicates that cancer-initiating cells (CICs) are responsible for cancer initiation, relapse, and metastasis. Colorectal carcinoma (CRC) is typically classified into proximal colon, distal colon, and rectal cancer. The gradual changes in CRC molecular features within the bowel may have considerable implications in colon and rectal CICs. Unfortunately, limited information is available on CICs derived from rectal cancer, although colon CICs have been described. Here we identified rectal CICs (R-CICs) that possess differentiation potential in tumors derived from patients with rectal adenocarcinoma. The R-CICs carried both CD44 and CD54 surface markers, while R-CICs and their immediate progenies carried potential epithelial–mesenchymal transition characteristics. These R-CICs generated tumors similar to their tumor of origin when injected into immunodeficient mice, differentiated into rectal epithelial cells in vitro, and were capable of self-renewal both in vitro and in vivo. More importantly, subpopulations of R-CICs resisted both 5-fluorouracil/calcium folinate/oxaliplatin (FolFox) and cetuximab treatment, which are the most common therapeutic regimens used for patients with advanced or metastatic rectal cancer. Thus, the identification, expansion, and properties of R-CICs provide an ideal cellular model to further investigate tumor progression and determine therapeutic resistance in these patients.
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| 3. |
- Lu, Fan, et al.
(författare)
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Long-Term Phosphorus Addition Strongly Weakens the Carbon Sink Function of a Temperate Peatland
- 2023
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Ingår i: Ecosystems. - : SPRINGER. - 1432-9840 .- 1435-0629. ; 26:1, s. 201-216
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Tidskriftsartikel (refereegranskat)abstract
- Peatlands are important nutrient-limited, carbon (C)-accumulating ecosystems where phosphorus (P) is one major limiting nutrient. An increase in P input to peatlands has been observed close to agricultural areas. However, the effects of P input on gross primary productivity (GPP), ecosystem respiration (ER) and net ecosystem exchange (NEE) of peatlands, especially in temperate Asia, have been rarely studied. We selected the P addition plots of a 12-year experiment simulating environmental change in a peatland in northeastern China to evaluate the effect of P addition (5 and 10 kg ha(-1) y(-1)) on carbon dioxide fluxes. Our results showed that the growth of Sphagnum was inhibited but that of vascular plants was facilitated by P addition, resulting in an unchanged GPP. P addition increased ER due to the increased activity potentials of N-acetyl-beta-glucosaminidase (NAG) and polyphenol oxidase (POX) that might, in turn, increase the metabolic rate of soil microbes and enhance the decomposition of peat. During the growing season, a mean net CO2 absorption of 0.002 mg m(-2) s(-1) was observed at high levels of P addition, which was much lower than that of 0.063 mg m(-2) s(-1) in the controls. The results suggest that long-term P addition will greatly weaken the C sequestration in peatlands by enhancing ER rather than reducing GPP. Our study highlights the importance of the response of vegetation and soil enzyme activities to P addition regarding peatland respiration and C sink function.
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| 4. |
- Voss, Erica A, et al.
(författare)
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Contextualising adverse events of special interest to characterise the baseline incidence rates in 24 million patients with COVID-19 across 26 databases: a multinational retrospective cohort study.
- 2023
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Ingår i: EClinicalMedicine. - 2589-5370. ; 58
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Tidskriftsartikel (refereegranskat)abstract
- Adverse events of special interest (AESIs) were pre-specified to be monitored for the COVID-19 vaccines. Some AESIs are not only associated with the vaccines, but with COVID-19. Our aim was to characterise the incidence rates of AESIs following SARS-CoV-2 infection in patients and compare these to historical rates in the general population.A multi-national cohort study with data from primary care, electronic health records, and insurance claims mapped to a common data model. This study's evidence was collected between Jan 1, 2017 and the conclusion of each database (which ranged from Jul 2020 to May 2022). The 16 pre-specified prevalent AESIs were: acute myocardial infarction, anaphylaxis, appendicitis, Bell's palsy, deep vein thrombosis, disseminated intravascular coagulation, encephalomyelitis, Guillain- Barré syndrome, haemorrhagic stroke, non-haemorrhagic stroke, immune thrombocytopenia, myocarditis/pericarditis, narcolepsy, pulmonary embolism, transverse myelitis, and thrombosis with thrombocytopenia. Age-sex standardised incidence rate ratios (SIR) were estimated to compare post-COVID-19 to pre-pandemic rates in each of the databases.Substantial heterogeneity by age was seen for AESI rates, with some clearly increasing with age but others following the opposite trend. Similarly, differences were also observed across databases for same health outcome and age-sex strata. All studied AESIs appeared consistently more common in the post-COVID-19 compared to the historical cohorts, with related meta-analytic SIRs ranging from 1.32 (1.05 to 1.66) for narcolepsy to 11.70 (10.10 to 13.70) for pulmonary embolism.Our findings suggest all AESIs are more common after COVID-19 than in the general population. Thromboembolic events were particularly common, and over 10-fold more so. More research is needed to contextualise post-COVID-19 complications in the longer term.None.
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| 5. |
- Wang, Zhaoming, et al.
(författare)
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Imputation and subset-based association analysis across different cancer types identifies multiple independent risk loci in the TERT-CLPTM1L region on chromosome 5p15.33
- 2014
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Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 23:24, s. 6616-6633
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Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies (GWAS) have mapped risk alleles for at least 10 distinct cancers to a small region of 63 000 bp on chromosome 5p15.33. This region harbors the TERT and CLPTM1L genes; the former encodes the catalytic subunit of telomerase reverse transcriptase and the latter may play a role in apoptosis. To investigate further the genetic architecture of common susceptibility alleles in this region, we conducted an agnostic subset-based meta-analysis (association analysis based on subsets) across six distinct cancers in 34 248 cases and 45 036 controls. Based on sequential conditional analysis, we identified as many as six independent risk loci marked by common single-nucleotide polymorphisms: five in the TERT gene (Region 1: rs7726159, P = 2.10 × 10(-39); Region 3: rs2853677, P = 3.30 × 10(-36) and PConditional = 2.36 × 10(-8); Region 4: rs2736098, P = 3.87 × 10(-12) and PConditional = 5.19 × 10(-6), Region 5: rs13172201, P = 0.041 and PConditional = 2.04 × 10(-6); and Region 6: rs10069690, P = 7.49 × 10(-15) and PConditional = 5.35 × 10(-7)) and one in the neighboring CLPTM1L gene (Region 2: rs451360; P = 1.90 × 10(-18) and PConditional = 7.06 × 10(-16)). Between three and five cancers mapped to each independent locus with both risk-enhancing and protective effects. Allele-specific effects on DNA methylation were seen for a subset of risk loci, indicating that methylation and subsequent effects on gene expression may contribute to the biology of risk variants on 5p15.33. Our results provide strong support for extensive pleiotropy across this region of 5p15.33, to an extent not previously observed in other cancer susceptibility loci.
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| 6. |
- Yusup, Shuayib, et al.
(författare)
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The Response of Spore Germination of Sphagnum Mosses to Single and Combined Fire-Related Cues
- 2022
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Ingår i: PLANTS. - : MDPI AG. - 2223-7747. ; 11:4
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Tidskriftsartikel (refereegranskat)abstract
- Plants in flammable ecosystems have different response strategies to fire, such as increasing germination after exposure to smoke and break of dormancy through heat shock. Peatlands are ecosystems that are more likely to be disturbed by fire with increasing temperatures, but it is not clear how fire affects spore germination of Sphagnum, the dominant plants in peatlands. Here, we hypothesize that Sphagnum spores respond positively to single and combined treatments of moderate heat and smoke (by increased germinability), while spore germinability decreases in response to high temperature. We exposed the Sphagnum spores of four selected species (S. angustifolium, S. fuscum, S. magellanicum and S. squarrosum) collected from peatlands in the Changbai Mountains to heat (40, 60 and 100 degrees C), on its own and combined with smoke-water treatments. Our results showed that a heat of 100 degrees C inhibited the spore germination or even killed spores of all species, while spore germination of three (Sphagnum angustifolium, S. fuscum and S. squarrosum) of the four species was promoted by 40 and 60 degrees C heat compared to the control (20 degrees C). Hollow species (S. angustifolium and S. squarrosum) showed a stronger positive responsive to heat than hummock species (S. fuscum and S. magellanicum). Sphagnum fuscum spores responded positively to the combined heat and smoke treatment while the other species did not. For the first time, we demonstrate the positive effects of heat on its own and in combination with smoke on spore germination in wetland mosses, which may be important for the establishment and persistence of peatmoss populations after fire.
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