| 1. |
- Abbasi, R., et al.
(författare)
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A Search for IceCube Sub-TeV Neutrinos Correlated with Gravitational-wave Events Detected By LIGO/Virgo
- 2023
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Ingår i: Astrophysical Journal. - : Institute of Physics Publishing (IOPP). - 1538-4357 .- 0004-637X. ; 959:2
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Tidskriftsartikel (refereegranskat)abstract
- The LIGO/Virgo collaboration published the catalogs GWTC-1, GWTC-2.1, and GWTC-3 containing candidate gravitational-wave (GW) events detected during its runs O1, O2, and O3. These GW events can be possible sites of neutrino emission. In this paper, we present a search for neutrino counterparts of 90 GW candidates using IceCube DeepCore, the low-energy infill array of the IceCube Neutrino Observatory. The search is conducted using an unbinned maximum likelihood method, within a time window of 1000 s, and uses the spatial and timing information from the GW events. The neutrinos used for the search have energies ranging from a few GeV to several tens of TeV. We do not find any significant emission of neutrinos, and place upper limits on the flux and the isotropic-equivalent energy emitted in low-energy neutrinos. We also conduct a binomial test to search for source populations potentially contributing to neutrino emission. We report a nondetection of a significant neutrino-source population with this test.
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| 2. |
- Abbasi, R., et al.
(författare)
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IceCat-1: The IceCube Event Catalog of Alert Tracks
- 2023
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Ingår i: Astrophysical Journal, Supplement Series. - : IOP Publishing Ltd. - 1538-4365 .- 0067-0049. ; 269:1
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Tidskriftsartikel (refereegranskat)abstract
- We present a catalog of likely astrophysical neutrino track-like events from the IceCube Neutrino Observatory. IceCube began reporting likely astrophysical neutrinos in 2016, and this system was updated in 2019. The catalog presented here includes events that were reported in real time since 2019, as well as events identified in archival data samples starting from 2011. We report 275 neutrino events from two selection channels as the first entries in the catalog, the IceCube Event Catalog of Alert Tracks, which will see ongoing extensions with additional alerts. The Gold and Bronze alert channels respectively provide neutrino candidates with a 50% and 30% probability of being astrophysical, on average assuming an astrophysical neutrino power-law energy spectral index of 2.19. For each neutrino alert, we provide the reconstructed energy, direction, false-alarm rate, probability of being astrophysical in origin, and likelihood contours describing the spatial uncertainty in the alert's reconstructed location. We also investigate a directional correlation of these neutrino events with gamma-ray and X-ray catalogs, including 4FGL, 3HWC, TeVCat, and Swift-BAT.
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| 3. |
- Abbasi, R., et al.
(författare)
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Search for 10-1000 GeV Neutrinos from Gamma-Ray Bursts with IceCube
- 2024
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Ingår i: Astrophysical Journal. - : Institute of Physics (IOP). - 1538-4357 .- 0004-637X. ; 964:2
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Tidskriftsartikel (refereegranskat)abstract
- We present the results of a search for 10-1000 GeV neutrinos from 2268 gamma-ray bursts (GRBs) over 8 yr of IceCube-DeepCore data. This work probes burst physics below the photosphere where electromagnetic radiation cannot escape. Neutrinos of tens of giga electronvolts are predicted in sub-photospheric collision of free-streaming neutrons with bulk-jet protons. In a first analysis, we searched for the most significant neutrino-GRB coincidence using six overlapping time windows centered on the prompt phase of each GRB. In a second analysis, we conducted a search for a group of GRBs, each individually too weak to be detectable, but potentially significant when combined. No evidence of neutrino emission is found for either analysis. The most significant neutrino coincidence is for Fermi-GBM GRB bn 140807500, with a p-value of 0.097 corrected for all trials. The binomial test used to search for a group of GRBs had a p-value of 0.65 after all trial corrections. The binomial test found a group consisting only of GRB bn 140807500 and no additional GRBs. The neutrino limits of this work complement those obtained by IceCube at tera electronvolt to peta electronvolt energies. We compare our findings for the large set of GRBs as well as GRB 221009A to the sub-photospheric neutron-proton collision model and find that GRB 221009A provides the most constraining limit on baryon loading. For a jet Lorentz factor of 300 (800), the baryon loading on GRB 221009A is lower than 3.85 (2.13) at a 90% confidence level.
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| 4. |
- Abbasi, R., et al.
(författare)
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Search for Galactic Core-collapse Supernovae in a Decade of Data Taken with the IceCube Neutrino Observatory
- 2024
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Ingår i: Astrophysical Journal. - : Institute of Physics Publishing (IOPP). - 1538-4357 .- 0004-637X. ; 961:1
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Tidskriftsartikel (refereegranskat)abstract
- The IceCube Neutrino Observatory has been continuously taking data to search for O(0.5–10) s long neutrino bursts since 2007. Even if a Galactic core-collapse supernova is optically obscured or collapses to a black hole instead of exploding, it will be detectable via the O(10) MeV neutrino burst emitted during the collapse. We discuss a search for such events covering the time between 2008 April 17 and 2019 December 31. Considering the average data taking and analysis uptime of 91.7% after all selection cuts, this is equivalent to 10.735 yr of continuous data taking. In order to test the most conservative neutrino production scenario, the selection cuts were optimized for a model based on an 8.8 solar mass progenitor collapsing to an O–Ne–Mg core. Conservative assumptions on the effects of neutrino oscillations in the exploding star were made. The final selection cut was set to ensure that the probability to detect such a supernova within the Milky Way exceeds 99%. No such neutrino burst was found in the data after performing a blind analysis. Hence, a 90% C.L. upper limit on the rate of core-collapse supernovae out to distances of ≈25 kpc was determined to be 0.23 yr−1. For the more distant Magellanic Clouds, only high neutrino luminosity supernovae will be detectable by IceCube, unless external information on the burst time is available. We determined a model-independent limit by parameterizing the dependence on the neutrino luminosity and the energy spectrum.
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| 5. |
- Abbasi, R., et al.
(författare)
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Search for neutrino lines from dark matter annihilation and decay with IceCube
- 2023
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Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 108:10
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Tidskriftsartikel (refereegranskat)abstract
- Dark matter particles in the Galactic Center and halo can annihilate or decay into a pair of neutrinos producing a monochromatic flux of neutrinos. The spectral feature of this signal is unique and it is not expected from any astrophysical production mechanism. Its observation would constitute a dark matter smoking gun signal. We performed the first dedicated search with a neutrino telescope for such signal, by looking at both the angular and energy information of the neutrino events. To this end, a total of five years of IceCube's DeepCore data has been used to test dark matter masses ranging from 10 GeV to 40 TeV. No significant neutrino excess was found and upper limits on the annihilation cross section, as well as lower limits on the dark matter lifetime, were set. The limits reached are of the order of 10-24 cm3/s for an annihilation and up to 1027 s for decaying dark matter. Using the same data sample we also derive limits for dark matter annihilation or decay into a pair of Standard Model charged particles.
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| 6. |
- Abbasi, R., et al.
(författare)
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Characterization of the astrophysical diffuse neutrino flux using starting track events in IceCube
- 2024
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Ingår i: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010 .- 2470-0029. ; 110:2
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Tidskriftsartikel (refereegranskat)abstract
- A measurement of the diffuse astrophysical neutrino spectrum is presented using IceCube data collected from 2011-2022 (10.3 years). We developed novel detection techniques to search for events with a contained vertex and exiting track induced by muon neutrinos undergoing a charged-current interaction. Searching for these starting track events allows us to not only more effectively reject atmospheric muons but also atmospheric neutrino backgrounds in the southern sky, opening a new window to the sub-100 TeV astrophysical neutrino sky. The event selection is constructed using a dynamic starting track veto and machine learning algorithms. We use this data to measure the astrophysical diffuse flux as a single power law flux (SPL) with a best-fit spectral index of γ=2.58-0.09+0.10 and per-flavor normalization of φper-flavorAstro=1.68-0.22+0.19×10-18×GeV-1 cm-2 s-1 sr-1 (at 100 TeV). The sensitive energy range for this dataset is 3-550 TeV under the SPL assumption. This data was also used to measure the flux under a broken power law, however we did not find any evidence of a low energy cutoff.
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| 7. |
- Abbasi, R., et al.
(författare)
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Citizen science for IceCube: Name that Neutrino
- 2024
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Ingår i: European Physical Journal Plus. - 2190-5444. ; 139:6
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Tidskriftsartikel (refereegranskat)abstract
- Name that Neutrino is a citizen science project where volunteers aid in classification of events for the IceCube Neutrino Observatory, an immense particle detector at the geographic South Pole. From March 2023 to September 2023, volunteers did classifications of videos produced from simulated data of both neutrino signal and background interactions. Name that Neutrino obtained more than 128,000 classifications by over 1800 registered volunteers that were compared to results obtained by a deep neural network machine-learning algorithm. Possible improvements for both Name that Neutrino and the deep neural network are discussed.
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| 8. |
- Abbasi, R., et al.
(författare)
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Improved modeling of in-ice particle showers for IceCube event reconstruction
- 2024
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 19:6
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Tidskriftsartikel (refereegranskat)abstract
- The IceCube Neutrino Observatory relies on an array of photomultiplier tubes to detect Cherenkov light produced by charged particles in the South Pole ice. IceCube data analyses depend on an in-depth characterization of the glacial ice, and on novel approaches in event reconstruction that utilize fast approximations of photoelectron yields. Here, a more accurate model is derived for event reconstruction that better captures our current knowledge of ice optical properties. When evaluated on a Monte Carlo simulation set, the median angular resolution for in-ice particle showers improves by over a factor of three compared to a reconstruction based on a simplified model of the ice. The most substantial improvement is obtained when including effects of birefringence due to the polycrystalline structure of the ice. When evaluated on data classified as particle showers in the high-energy starting events sample, a significantly improved description of the events is observed.
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| 9. |
- Abbasi, R., et al.
(författare)
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Measurement of atmospheric neutrino mixing with improved IceCube DeepCore calibration and data processing
- 2023
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Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 108:1
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Tidskriftsartikel (refereegranskat)abstract
- We describe a new data sample of IceCube DeepCore and report on the latest measurement of atmospheric neutrino oscillations obtained with data recorded between 2011-2019. The sample includes significant improvements in data calibration, detector simulation, and data processing, and the analysis benefits from a sophisticated treatment of systematic uncertainties, with significantly greater level of detail since our last study. By measuring the relative fluxes of neutrino flavors as a function of their reconstructed energies and arrival directions we constrain the atmospheric neutrino mixing parameters to be sin2θ23=0.51±0.05 and Δm322=2.41±0.07×10-3 eV2, assuming a normal mass ordering. The errors include both statistical and systematic uncertainties. The resulting 40% reduction in the error of both parameters with respect to our previous result makes this the most precise measurement of oscillation parameters using atmospheric neutrinos. Our results are also compatible and complementary to those obtained using neutrino beams from accelerators, which are obtained at lower neutrino energies and are subject to different sources of uncertainties.
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| 10. |
- Abbasi, R., et al.
(författare)
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Search for Continuous and Transient Neutrino Emission Associated with IceCube's Highest-energy Tracks: An 11 yr Analysis
- 2024
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Ingår i: Astrophysical Journal. - 1538-4357 .- 0004-637X. ; 964:1
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Tidskriftsartikel (refereegranskat)abstract
- IceCube alert events are neutrinos with a moderate-to-high probability of having astrophysical origin. In this study, we analyze 11 yr of IceCube data and investigate 122 alert events and a selection of high-energy tracks detected between 2009 and the end of 2021. This high-energy event selection (alert events + high-energy tracks) has an average probability of >= 0.5 of being of astrophysical origin. We search for additional continuous and transient neutrino emission within the high-energy events' error regions. We find no evidence for significant continuous neutrino emission from any of the alert event directions. The only locally significant neutrino emission is the transient emission associated with the blazar TXS 0506+056, with a local significance of 3 sigma, which confirms previous IceCube studies. When correcting for 122 test positions, the global p-value is 0.156 and compatible with the background hypothesis. We constrain the total continuous flux emitted from all 122 test positions at 100 TeV to be below 1.2 x 10-15 (TeV cm2 s)-1 at 90% confidence assuming an E -2 spectrum. This corresponds to 4.5% of IceCube's astrophysical diffuse flux. Overall, we find no indication that alert events in general are linked to lower-energetic continuous or transient neutrino emission.
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| 11. |
- Abbasi, R., et al.
(författare)
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Search for decoherence from quantum gravity with atmospheric neutrinos
- 2024
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Ingår i: Nature Physics. - 1745-2481 .- 1745-2473. ; 20:6, s. 913-920
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Tidskriftsartikel (refereegranskat)abstract
- Neutrino oscillations at the highest energies and longest baselines can be used to study the structure of spacetime and test the fundamental principles of quantum mechanics. If the metric of spacetime has a quantum mechanical description, its fluctuations at the Planck scale are expected to introduce non-unitary effects that are inconsistent with the standard unitary time evolution of quantum mechanics. Neutrinos interacting with such fluctuations would lose their quantum coherence, deviating from the expected oscillatory flavour composition at long distances and high energies. Here we use atmospheric neutrinos detected by the IceCube South Pole Neutrino Observatory in the energy range of 0.5-10.0 TeV to search for coherence loss in neutrino propagation. We find no evidence of anomalous neutrino decoherence and determine limits on neutrino-quantum gravity interactions. The constraint on the effective decoherence strength parameter within an energy-independent decoherence model improves on previous limits by a factor of 30. For decoherence effects scaling as E2, our limits are advanced by more than six orders of magnitude beyond past measurements compared with the state of the art. Interactions of atmospheric neutrinos with quantum-gravity-induced fluctuations of the metric of spacetime would lead to decoherence. The IceCube Collaboration constrains such interactions with atmospheric neutrinos.
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| 12. |
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| 13. |
- Abbasi, R., et al.
(författare)
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Search for Extended Sources of Neutrino Emission in the Galactic Plane with IceCube
- 2023
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Ingår i: Astrophysical Journal. - : Institute of Physics (IOP). - 0004-637X .- 1538-4357. ; 956:1
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Tidskriftsartikel (refereegranskat)abstract
- The Galactic plane, harboring a diffuse neutrino flux, is a particularly interesting target in which to study potential cosmic-ray acceleration sites. Recent gamma-ray observations by HAWC and LHAASO have presented evidence for multiple Galactic sources that exhibit a spatially extended morphology and have energy spectra continuing beyond 100 TeV. A fraction of such emission could be produced by interactions of accelerated hadronic cosmic rays, resulting in an excess of high-energy neutrinos clustered near these regions. Using 10 years of IceCube data comprising track-like events that originate from charged-current muon neutrino interactions, we perform a dedicated search for extended neutrino sources in the Galaxy. We find no evidence for time-integrated neutrino emission from the potential extended sources studied in the Galactic plane. The most significant location, at 2.6 sigma post-trials, is a 1.degrees 7 sized region coincident with the unidentified TeV gamma-ray source 3HWC J1951+266. We provide strong constraints on hadronic emission from several regions in the galaxy.
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| 14. |
- Alsmark, U. Cecilia, et al.
(författare)
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Horizontal gene transfer in eukaryotic parasites : a case study of Entamoeba histolytica and Trichomonas vaginalis
- 2009
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Ingår i: Horizontal Gene Transfer. - Totowa, NJ : Humana Press. - 9781603278522 - 9781603278539 ; , s. 489-500
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Over the past few years it has become apparent that horizontal gene transfer (HGT) has played an important role in the evolution of pathogenic prokaryotes. What is less clear is the exact role that HGT has played in shaping the metabolism of eukaryotic organisms. The main problems are the reliable inference of HGT on a genomic scale as well as the functional assignment of genes in these poorly studied organisms. We have screened the completed genomes of the protists Entamoeba histolytica and Trichomonas vaginalis for cases of HGT from prokaryotes. Using a fast primary screen followed by a conservative phylogenetic approach, we found 68 and 153 recent cases of HGT in the respective organisms. The majority of transferred genes that fall into functional categories code for enzymes involved in metabolism. We found a broad range of prokaryotic lineages represented among the donors, but organisms that share similar environmental niches with E. histolytica and T. vaginalis, such as the gut and the vaginal mucosa, dominate.
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| 15. |
- Carlsson, C., et al.
(författare)
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Voluntary associations for cancer patients in Sweden: supportive activities
- 2001
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Ingår i: Supportive Care in Cancer. - : Springer Science and Business Media LLC. - 0941-4355 .- 1433-7339. ; 9:8, s. 581-590
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Tidskriftsartikel (refereegranskat)abstract
- Our aim was to describe voluntary associations for patients with cancer in Sweden (n=108) and their activities, type and extent of member support, and the associations' collaboration with the health care system. A specially constructed questionnaire with structured and open questions was used for the investigation. The frequency of answers was 89%. The results show in the broadest sense that the associations have two missions. The direct patient-related mission concerns providing patients with support in the form of close proximity, approachability and through distribution of knowledge together with financial and practical support; the indirect patient-related mission deals with activities aimed at improving conditions for patients in general within the health care system and by influencing authorities as well as supporting family members and significant others and providing financing. The associations collaborate with the health care system, although they face difficulties in becoming 'sanctioned' and in establishing positive relationships with the health care community. The associations display a positive attitude towards their cause and the personal gratification that the voluntary work brings. In general, the findings indicate that the associations have a potential to help patients live and cope with their cancer disease.
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| 16. |
- Fagerberg, Linn, et al.
(författare)
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Contribution of antibody-based protein profiling to the human chromosome-centric proteome project (C-HPP)
- 2013
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Ingår i: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3893 .- 1535-3907. ; 12:6, s. 2439-2448
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Tidskriftsartikel (refereegranskat)abstract
- A gene-centric Human Proteome Project has been proposed to characterize the human protein-coding genes in a chromosome-centered manner to understand human biology and disease. Here, we report on the protein evidence for all genes predicted from the genome sequence based on manual annotation from literature (UniProt), antibody-based profiling in cells, tissues and organs and analysis of the transcript profiles using next generation sequencing in human cell lines of different origins. We estimate that there is good evidence for protein existence for 69% (n = 13985) of the human protein-coding genes, while 23% have only evidence on the RNA level and 7% still lack experimental evidence. Analysis of the expression patterns shows few tissue-specific proteins and approximately half of the genes expressed in all the analyzed cells. The status for each gene with regards to protein evidence is visualized in a chromosome-centric manner as part of a new version of the Human Protein Atlas (www.proteinatlas.org).
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| 17. |
- Gaber, Alexander, et al.
(författare)
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High expression of tumour-associated trypsin inhibitor correlates with liver metastasis and poor prognosis in colorectal cancer
- 2009
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Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 0007-0920 .- 1532-1827. ; 100:10, s. 1540-1548
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Tidskriftsartikel (refereegranskat)abstract
- Increased expression of tumour-associated trypsin inhibitor (TATI) in tumour tissue and/or serum has been associated with poor survival in various cancer forms. Moreover, a proinvasive function of TATI has been shown in colon cancer cell lines. In this study, we have examined the prognostic significance of tumour-specific TATI expression in colorectal cancer, assessed by immunohistochemistry (IHC) on tissue microarrays (TMAs) with tumour specimens from two independent patient cohorts. Kaplan-Meier analysis and Cox proportional hazards modelling were used to estimate time to recurrence, disease-free survival and overall survival. In both cohorts, a high (>50% of tumour cells) TATI expression was an independent predictor of a significantly shorter overall survival. In cohort II, in multivariate analysis including age, gender, disease stage, differentiation grade, vascular invasion and carcinoembryonal antigen (CEA), high TATI expression was associated with a significantly decreased overall survival (HR=1.82; 95% CI=1.19-2.79) and disease-free survival (HR=1.56; 95% CI=1.05-2.32) in curatively treated patients. Moreover, there was an increased risk for liver metastasis in both cohorts that remained significant in multivariate analysis in cohort II (HR=2.85; 95% CI=1.43-5.66). In conclusion, high TATI expression is associated with liver metastasis and is an independent predictor of poor prognosis in patients with colorectal cancer.
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| 18. |
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| 19. |
- Huang, Hua, 1986-, et al.
(författare)
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ELTD1-deletion reduces vascular abnormality and improves T-cell recruitment after PD-1 blockade in glioma.
- 2021
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Ingår i: Neuro-Oncology. - : Oxford University Press. - 1522-8517 .- 1523-5866. ; 24:3, s. 398-411
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Tumor vessels in glioma are molecularly and functionally abnormal, contributing to treatment resistance. Proteins differentially expressed in glioma vessels can change vessel phenotype and be targeted for therapy. ELTD1 (Adgrl4) is an orphan member of the adhesion G-protein-coupled receptor family upregulated in glioma vessels, and has been suggested as a potential therapeutic target. However, the role of ELTD1 in regulating vessel function in glioblastoma is poorly understood.METHODS: ELTD1 expression in human gliomas and its association with patient survival was determined using tissue microarrays and public databases. The role of ELTD1 in regulating tumor vessel phenotype was analyzed using orthotopic glioma models and ELTD1 -/- mice. Endothelial cells isolated from murine gliomas were transcriptionally profiled to determine differentially expressed genes and pathways. The consequence of ELTD1-deletion on glioma immunity was determined by treating tumor bearing mice with PD-1-blocking antibodies.RESULTS: ELTD1 levels were upregulated in human glioma vessels, increased with tumor malignancy, and were associated with poor patient survival. Progression of orthotopic gliomas was not affected by ELTD1-deletion, however, tumor vascular function was improved in ELTD1 -/- mice. Bioinformatic analysis of differentially expressed genes indicated increased inflammatory response and decreased proliferation in tumor endothelium in ELTD1 -/- mice. Consistent with an enhanced inflammatory response, ELTD1-deletion improved T-cell infiltration in GL261-bearing mice after PD-1 checkpoint blockade.CONCLUSION: Our data demonstrate that ELTD1 participates in inducing vascular dysfunction in glioma, and suggests that targeting of ELTD1 may normalize the vessels and improve the response to immunotherapy.
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| 20. |
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| 21. |
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| 22. |
- Matic, L. P., et al.
(författare)
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Novel Multiomics Profiling of Human Carotid Atherosclerotic Plaques and Plasma Reveals Biliverdin Reductase B as a Marker of Intraplaque Hemorrhage
- 2018
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Ingår i: JACC: Basic to Translational Science. - : Elsevier BV. - 2452-302X. ; 3:4, s. 464-480
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Tidskriftsartikel (refereegranskat)abstract
- Clinical tools to identify individuals with unstable atherosclerotic lesions are required to improve prevention of myocardial infarction and ischemic stroke. Here, a systems-based analysis of atherosclerotic plaques and plasma from patients undergoing carotid endarterectomy for stroke prevention was used to identify molecular signatures with a causal relationship to disease. Local plasma collected in the lesion proximity following clamping prior to arteriotomy was profiled together with matched peripheral plasma. This translational workflow identified biliverdin reductase B as a novel marker of intraplaque hemorrhage and unstable carotid atherosclerosis, which should be investigated as a potential predictive biomarker for cardiovascular events in larger cohorts.
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| 23. |
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| 24. |
- Perisic, L., et al.
(författare)
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Profiling of atherosclerotic lesions by gene and tissue microarrays reveals pcsk6 as a novel protease in unstable carotid atherosclerosis
- 2013
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Ingår i: Arteriosclerosis, Thrombosis and Vascular Biology. - 1079-5642 .- 1524-4636. ; 33:10, s. 2432-2443
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE - : Carotid plaque instability is a major cause of ischemic stroke, but detailed knowledge about underlying molecular pathways is still lacking. Here, we evaluated large-scale transcriptomic and protein expression profiling in a biobank of carotid endarterectomies followed by characterization of identified candidates, as a platform for discovery of novel proteins differentially regulated in unstable carotid lesions. APPROACH AND RESULTS - : Genes highly upregulated in symptomatic versus asymptomatic plaques were selected from Affymetrix microarray analyses (n=127 plaques), and tissue microarrays constructed from 34 lesions were assayed for 21 corresponding proteins by immunohistochemistry. Quantification of stainings demonstrated differential expression of CD36, CD137, and DOCK7 (P<0.05) in unstable versus stable lesions and the most significant upregulation of a proprotein convertase, PCSK6 (P<0.0001). Increased expression of PCSK6 in symptomatic lesions was verified by quantitative real-time polymerase chain reaction (n=233), and the protein was localized to smooth muscle α-actin positive cells and extracellular matrix of the fibrous cap by immunohistochemistry. PCSK6 expression positively correlated to genes associated with inflammation, matrix degradation, and mitogens in microarrays. Stimulation of human carotid smooth muscle cells in vitro with cytokines caused rapid induction of PCSK6 mRNA. CONCLUSIONS - : Using a combination of transcriptomic and tissue microarray profiling, we demonstrate a novel approach to identify proteins differentially expressed in unstable carotid atherosclerosis. The proprotein convertase PCSK6 was detected at increased levels in the fibrous cap of symptomatic carotid plaques, possibly associated with key processes in plaque rupture such as inflammation and extracellular matrix remodeling. Further studies are needed to clarify the role of PCSK6 in atherosclerosis.
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| 25. |
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| 26. |
- Pontén, U, et al.
(författare)
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Traumatiska hjärnskador
- 1996
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Ingår i: En bok om hjärnan. - : Tiden/Rabén Prisma. ; , s. 303-
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 27. |
- Sinding, Mikkel-Holger S., et al.
(författare)
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Arctic-adapted dogs emerged at the Pleistocene-Holocene transition
- 2020
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 368:6498
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Tidskriftsartikel (refereegranskat)abstract
- Although sled dogs are one of the most specialized groups of dogs, their origin and evolution has received much less attention than many other dog groups. We applied a genomic approach to investigate their spatiotemporal emergence by sequencing the genomes of 10 modern Greenland sled dogs, an similar to 9500-year-old Siberian dog associated with archaeological evidence for sled technology, and an similar to 33,000-year-old Siberian wolf. We found noteworthy genetic similarity between the ancient dog and modern sled dogs. We detected gene flow from Pleistocene Siberian wolves, but not modern American wolves, to present-day sled dogs. The results indicate that the major ancestry of modern sled dogs traces back to Siberia, where sled dog-specific haplotypes of genes that potentially relate to Arctic adaptation were established by 9500 years ago.
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| 28. |
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| 29. |
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| 30. |
- Zhang, C., et al.
(författare)
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LIPG-promoted lipid storage mediates adaptation to oxidative stress in breast cancer
- 2019
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 145:4, s. 901-915
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Tidskriftsartikel (refereegranskat)abstract
- Endothelial lipase (LIPG) is a cell surface associated lipase that displays phospholipase A1 activity towards phosphatidylcholine present in high‐density lipoproteins (HDL). LIPG was recently reported to be expressed in breast cancer and to support proliferation, tumourigenicity and metastasis. Here we show that severe oxidative stress leading to AMPK activation triggers LIPG upregulation, resulting in intracellular lipid droplet accumulation in breast cancer cells, which supports survival. Neutralizing oxidative stress abrogated LIPG upregulation and the concomitant lipid storage. In human breast cancer, high LIPG expression was observed in a limited subset of tumours and was significantly associated with shorter metastasis‐free survival in node‐negative, untreated patients. Moreover, expression of PLIN2 and TXNRD1 in these tumours indicated a link to lipid storage and oxidative stress. Altogether, our findings reveal a previously unrecognized role for LIPG in enabling oxidative stress‐induced lipid droplet accumulation in tumour cells that protects against oxidative stress, and thus supports tumour progression.
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| 31. |
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| 32. |
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| 33. |
- Österholm, C., et al.
(författare)
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Increased expression of heparanase in symptomatic carotid atherosclerosis
- 2013
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Ingår i: Atherosclerosis. - : Elsevier BV. - 0021-9150 .- 1879-1484. ; 226:1, s. 67-73
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Proliferation of smooth muscle cells (SMCs) can stabilize atherosclerotic lesions but the molecular mechanisms that regulate this process in humans are largely unknown. We have previously shown that heparan sulfate proteoglycans (HSPGs), such as perlecan, regulate SMC growth in animal models by modulating heparin-binding mitogens. Since perlecan is expressed at low levels in human atherosclerosis, we speculated that the effect of heparan sulfate (HS) in human disease was rather influenced by HS degradation and investigated the expression of heparanase (HPSE) in human carotid endarterectomies. Methods and results: Gene expression analysis from 127 endarterectomies in the BiKE database revealed increased expression of HPSE in carotid plaques compared with normal arteries, and a further elevation in symptomatic lesions. Increased HPSE protein expression in symptomatic plaque tissue was verified by tissue microarrays. HPSE mRNA levels correlated positively with expression of inflammatory markers IL-18, RANTES and IL-1β, and also T-cell co-stimulatory molecules, such as B7.2, CD28, LFA-1 and 4-1BB. Previously reported single nucleotide polymorphisms within HPSE were associated with differential mRNA expression in plaques. Immunohistochemistry revealed that inflammatory cells were major producers of HPSE in plaque tissue. HPSE immunoreactivity was also observed in SMCs adjacent to the necrotic core and was co-localized to deposits of fibrin. Conclusions: This study demonstrates increased expression of HPSE in human atherosclerosis associated with inflammation, coagulation and plaque instability. Since HS can regulate SMC proliferation and influence plaque stability, the findings suggest that HPSE degradation of HS take part in the regulation of SMC function in human atherosclerosis.
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