| 1. |
- Glasbey, JC, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 2. |
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| 3. |
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| 4. |
- Zuntini, Alexandre R., et al.
(författare)
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Phylogenomics and the rise of the angiosperms
- 2024
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Ingår i: NATURE. - 0028-0836 .- 1476-4687. ; 629, s. 843-850
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Tidskriftsartikel (refereegranskat)abstract
- Angiosperms are the cornerstone of most terrestrial ecosystems and human livelihoods(1,2). A robust understanding of angiosperm evolution is required to explain their rise to ecological dominance. So far, the angiosperm tree of life has been determined primarily by means of analyses of the plastid genome(3,4). Many studies have drawn on this foundational work, such as classification and first insights into angiosperm diversification since their Mesozoic origins(5-7). However, the limited and biased sampling of both taxa and genomes undermines confidence in the tree and its implications. Here, we build the tree of life for almost 8,000 (about 60%) angiosperm genera using a standardized set of 353 nuclear genes(8). This 15-fold increase in genus-level sampling relative to comparable nuclear studies(9) provides a critical test of earlier results and brings notable change to key groups, especially in rosids, while substantiating many previously predicted relationships. Scaling this tree to time using 200 fossils, we discovered that early angiosperm evolution was characterized by high gene tree conflict and explosive diversification, giving rise to more than 80% of extant angiosperm orders. Steady diversification ensued through the remaining Mesozoic Era until rates resurged in the Cenozoic Era, concurrent with decreasing global temperatures and tightly linked with gene tree conflict. Taken together, our extensive sampling combined with advanced phylogenomic methods shows the deep history and full complexity in the evolution of a megadiverse clade.
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Perez-Nadales, Elena, et al.
(författare)
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Predictors of mortality in solid organ transplant recipients with bloodstream infections due to carbapenemase-producing Enterobacterales : The impact of cytomegalovirus disease and lymphopenia
- 2020
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Ingår i: American Journal of Transplantation. - : WILEY. - 1600-6135 .- 1600-6143. ; 20:6, s. 1629-1641
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Tidskriftsartikel (refereegranskat)abstract
- Treatment of carbapenemase-producing Enterobacterales bloodstream infections in solid organ transplant recipients is challenging. The objective of this study was to develop a specific score to predict mortality in solid organ transplant recipients with carbapenemase-producing Enterobacterales bloodstream infections. A multinational, retrospective (2004-2016) cohort study (INCREMENT-SOT, ClinicalTrials.gov NCT02852902) was performed. The main outcome variable was 30-day all-cause mortality. The INCREMENT-SOT-CPE score was developed using logistic regression. The global cohort included 216 patients. The final logistic regression model included the following variables: INCREMENT-CPE mortality score >= 8 (8 points), no source control (3 points), inappropriate empirical therapy (2 points), cytomegalovirus disease (7 points), lymphopenia (4 points), and the interaction between INCREMENT-CPE score >= 8 and CMV disease (minus 7 points). This score showed an area under the receiver operating characteristic curve of 0.82 (95% confidence interval [CI] 0.76-0.88) and classified patients into 3 strata: 0-7 (low mortality), 8-11 (high mortality), and 12-17 (very-high mortality). We performed a stratified analysis of the effect of monotherapy vs combination therapy among 165 patients who received appropriate therapy. Monotherapy was associated with higher mortality only in the very-high (adjusted hazard ratio [HR] 2.82, 95% CI 1.13-7.06, P = .03) and high (HR 9.93, 95% CI 2.08-47.40, P = .004) mortality risk strata. A score-based algorithm is provided for therapy guidance.
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| 9. |
- Afifi, K., et al.
(författare)
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Features of intracranial hemorrhage in cerebral venous thrombosis
- 2020
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Ingår i: Journal of Neurology. - : Springer Science and Business Media LLC. - 0340-5354 .- 1432-1459. ; 267, s. 3292-3298
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Tidskriftsartikel (refereegranskat)abstract
- Background Cerebral venous thrombosis (CVT) is associated with intracranial hemorrhage. Aim To identify clinical and imaging features of CVT-associated intracranial hemorrhage. We hypothesized that higher clot burden would be associated with a higher risk of intracranial hemorrhage. Methods We performed a retrospective analysis of an international, multicenter cohort of patients with confirmed cerebral venous thrombosis who underwent computed tomography within 2 weeks of symptom onset. Clinical and imaging features were compared between patients with and without intracranial hemorrhage. Clot burden was assessed by counting the number of thrombosed venous sinuses and veins on confirmatory imaging. Results We enrolled 260 patients from 10 institutions in Europe and Mexico. The mean age was 42 years and 74% were female. Intracranial hemorrhage was found in 102 (39%). Among them parenchymal hemorrhage occurred in 64 (63%), in addition, small juxta-cortical hemorrhage was found in 30 (29%), subarachnoid hemorrhage in 24 (24%) and subdural hemorrhage in 11 (11%). Multiple concomitant types of hemorrhage occurred in 23 (23%). Older age and superior sagittal thrombosis involvement were associated with presence of hemorrhage. The number of thrombosed venous sinuses was not associated with intracranial hemorrhage (median number IQRInterquartile ratio] of sinuses/veins involved with hemorrhage 2 (1-3) vs. 2 (1-3) without hemorrhage,p = 0.4). Conclusion The high rate of intracranial hemorrhage in cerebral venous thrombosis is not explained by widespread involvement of the venous sinuses. Superior sagittal sinus involvement is associated with higher bleeding risk.
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| 10. |
- Buyck, P. J., et al.
(författare)
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Diagnostic accuracy of noncontrast CT imaging markers in cerebral venous thrombosis
- 2019
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Ingår i: Neurology. - : Ovid Technologies (Wolters Kluwer Health). - 0028-3878 .- 1526-632X. ; 92:8
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Tidskriftsartikel (refereegranskat)abstract
- Objective To assess the added diagnostic value of semiquantitative imaging markers on noncontrast CT scans in cerebral venous thrombosis (CVT). Methods In a retrospective, multicenter, blinded, case-control study of patients with recent onset (<2 weeks) CVT, 3 readers assessed (1) the accuracy of the visual impression of CVT based on a combination of direct and indirect signs, (2) the accuracy of attenuation values of the venous sinuses in Hounsfield units (with adjustment for hematocrit levels), and (3) the accuracy of attenuation ratios of affected vs unaffected sinuses in comparison with reference standard MRI or CT angiography. Controls were age-matched patients with (sub)acute neurologic presentations. Results We enrolled 285 patients with CVT and 303 controls from 10 international centers. Sensitivity of visual impression of thrombosis ranged from 41% to 73% and specificity ranged from 97% to 100%. Attenuation measurement had an area under the curve (AUC) of 0.78 (95% confidence interval [CI] 0.74-0.81). After adjustment for hematocrit, the AUC remained 0.78 (95% CI 0.74-0.81). The analysis of attenuation ratios of affected vs unaffected sinuses had AUC of 0.83 (95% CI 0.8-0.86). Adding this imaging marker significantly improved discrimination, but sensitivity when tolerating a false-positive rate of 20% was not higher than 76% (95% CI 0.70-0.81). Conclusion Semiquantitative analysis of attenuation values for diagnosis of CVT increased sensitivity but still failed to identify 1 out of 4 CVT. Classification of evidence This study provides Class II evidence that visual analysis of plain CT with or without attenuation measurements has high specificity but only moderate sensitivity for CVT.
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| 11. |
- Tinetti, G., et al.
(författare)
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A chemical survey of exoplanets with ARIEL
- 2018
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Ingår i: Experimental Astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 46:1, s. 135-209
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Tidskriftsartikel (refereegranskat)abstract
- Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H2O, CO2, CH4 NH3, HCN, H2S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.
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| 12. |
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| 13. |
- Borsato, M., et al.
(författare)
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Unleashing the full power of LHCb to probe stealth new physics
- 2022
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Ingår i: Reports on Progress in Physics. - : IOP Publishing. - 0034-4885 .- 1361-6633. ; 85:2
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we describe the potential of the LHCb experiment to detect stealth physics. This refers to dynamics beyond the standard model that would elude searches that focus on energetic objects or precision measurements of known processes. Stealth signatures include long-lived particles and light resonances that are produced very rarely or together with overwhelming backgrounds. We will discuss why LHCb is equipped to discover this kind of physics at the Large Hadron Collider and provide examples of well-motivated theoretical models that can be probed with great detail at the experiment.
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| 14. |
- Cavieres, Lohengrin A., et al.
(författare)
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Facilitative plant interactions and climate simultaneously drive alpine plant diversity
- 2014
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Ingår i: Ecology Letters. - : Wiley. - 1461-0248 .- 1461-023X. ; 17:2, s. 193-202
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Tidskriftsartikel (refereegranskat)abstract
- Interactions among species determine local-scale diversity, but local interactions are thought to have minor effects at larger scales. However, quantitative comparisons of the importance of biotic interactions relative to other drivers are rarely made at larger scales. Using a data set spanning 78 sites and five continents, we assessed the relative importance of biotic interactions and climate in determining plant diversity in alpine ecosystems dominated by nurse-plant cushion species. Climate variables related with water balance showed the highest correlation with richness at the global scale. Strikingly, although the effect of cushion species on diversity was lower than that of climate, its contribution was still substantial. In particular, cushion species enhanced species richness more in systems with inherently impoverished local diversity. Nurse species appear to act as a ‘safety net’ sustaining diversity under harsh conditions, demonstrating that climate and species interactions should be integrated when predicting future biodiversity effects of climate change.
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| 15. |
- Kloske, C. M., et al.
(författare)
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APOE and immunity: Research highlights
- 2023
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Ingår i: Alzheimers & Dementia. - : Wiley. - 1552-5260 .- 1552-5279. ; 19:6, s. 2677-2696
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Forskningsöversikt (refereegranskat)abstract
- INTRODUCTIONAt the Alzheimer's Association's APOE and Immunity virtual conference, held in October 2021, leading neuroscience experts shared recent research advances on and inspiring insights into the various roles that both the apolipoprotein E gene (APOE) and facets of immunity play in neurodegenerative diseases, including Alzheimer's disease and other dementias. METHODSThe meeting brought together more than 1200 registered attendees from 62 different countries, representing the realms of academia and industry. RESULTSDuring the 4-day meeting, presenters illuminated aspects of the cross-talk between APOE and immunity, with a focus on the roles of microglia, triggering receptor expressed on myeloid cells 2 (TREM2), and components of inflammation (e.g., tumor necrosis factor alpha [TNF alpha]). DISCUSSIONThis manuscript emphasizes the importance of diversity in current and future research and presents an integrated view of innate immune functions in Alzheimer's disease as well as related promising directions in drug development.
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| 16. |
- Bergman, Lina, 1982, et al.
(författare)
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Preeclampsia and increased permeability over the blood brain barrier - a role of vascular endothelial growth receptor 2.
- 2021
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Ingår i: American journal of hypertension. - : Oxford University Press (OUP). - 1941-7225 .- 0895-7061. ; 34:1, s. 73-81
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Tidskriftsartikel (refereegranskat)abstract
- Cerebral complications in preeclampsia are leading causes of maternal mortality worldwide but the underlying pathophysiology is largely unknown and a challenge to study. Using an in vitro model of the human blood brain barrier (BBB), we explored the role of vascular endothelial growth factor receptor 2 (VEGFR2) in preeclampsia.The human brain endothelial cell line (hCMEC/D3) cultured on Tranwells insert were exposed (12h) to plasma from women with preeclampsia (n=28), normal pregnancy (n=28) and non-pregnant (n=16) controls. Transendothelial electrical resistance (TEER) and permeability to 70kDa FITC-dextran were measured for assessment of BBB integrity. We explored possible underlying mechanisms, with focus on expression of tight junction proteins and phosphorylation of two tyrosine residues of VEGFR2, associated with vascular permeability and migration (pY951) and cell proliferation (pY1175). Plasma concentrations of soluble FMS like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) were measured in order to establish correlations with in vitro results.hCMEC/D3 exposed to plasma from women with preeclampsia exhibited reduced TEER and increased permeability to 70kDa FITC-dextran. Further, these cells up-regulated the mRNA levels of VEGFR2, as well as pY951-VEGFR2; but reduced pY1175-VEGFR2 (p&0.05 in all cases). No difference in mRNA expression of tight junction protein was observed between gruops. There was no correlation between angiogenic biomarkers and BBB permeability.We present a promising in vitro model of the BBB in preeclampsia. Selective tyrosine phosphorylation of VEGFR2 may participate in the increased BBB permeability in preeclampsia irrespective of plasma concentrations of angiogenic biomarkers.
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| 17. |
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| 18. |
- Parra, M. A., et al.
(författare)
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Biomarkers for dementia in Latin American countries: Gaps and opportunities
- 2023
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Ingår i: Alzheimers & Dementia. - : Wiley. - 1552-5260 .- 1552-5279. ; 19:2, s. 721-735
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Tidskriftsartikel (refereegranskat)abstract
- Limited knowledge on dementia biomarkers in Latin American and Caribbean (LAC) countries remains a serious barrier. Here, we reported a survey to explore the ongoing work, needs, interests, potential barriers, and opportunities for future studies related to biomarkers. The results show that neuroimaging is the most used biomarker (73%), followed by genetic studies (40%), peripheral fluids biomarkers (31%), and cerebrospinal fluid biomarkers (29%). Regarding barriers in LAC, lack of funding appears to undermine the implementation of biomarkers in clinical or research settings, followed by insufficient infrastructure and training. The survey revealed that despite the above barriers, the region holds a great potential to advance dementia biomarkers research. Considering the unique contributions that LAC could make to this growing field, we highlight the urgent need to expand biomarker research. These insights allowed us to propose an action plan that addresses the recommendations for a biomarker framework recently proposed by regional experts.
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| 19. |
- Pelaz, B, et al.
(författare)
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Diverse Applications of Nanomedicine
- 2017
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Ingår i: ACS nano. - : American Chemical Society (ACS). - 1936-086X .- 1936-0851. ; 11:3, s. 2313-2381
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Tidskriftsartikel (refereegranskat)
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| 20. |
- Peypoch, O, et al.
(författare)
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The TAGA Study: A Study of Factors Determining Aortic Diameter in Families at High Risk of Abdominal Aortic Aneurysm Reveal Two New Candidate Genes
- 2020
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Ingår i: Journal of clinical medicine. - : MDPI AG. - 2077-0383. ; 9:4
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Tidskriftsartikel (refereegranskat)abstract
- A variety of disorders are known to be related with aortic geometry, among them abdominal aortic aneurysm (AAA). This work aims to present the main determinants of abdominal aortic diameter in a new cohort of families at high risk of AAA. The Triple-A Genomic Analysis (TAGA) study comprises 407 individuals related in 12 families. Each family was collected through a proband with AAA. We calculated heritability and genetic correlations between abdominal aortic diameter and clinical parameters. A genome-wide linkage scan was performed based on 4.6 million variants. A predictive model was calculated with conditional forest. Heritability of the abdominal aortic diameter was 34%. Old age, male sex, higher height, weight, creatinine levels in serum, and better lung capacity were the best predictors of aortic diameter. Linkage analyses suggested the implication of Epidermal Growth Factor Receptor (EGFR) and Betacellulin (BTC) genes with aortic diameter. This is the first study to evaluate genetic components of variation of the aortic diameter in a population of AAA high-risk individuals. These results reveal EGFR, a gene that had been previously implicated in AAA, as a determinant of aortic diameter variation in healthy genetically enriched individuals, and might indicate that a common genetic background could determine the diameter of the aorta and future risk of AAA.
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| 21. |
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| 22. |
- Razis, E., et al.
(författare)
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Assessment of the management of carcinomatous meningitis from breast cancer globally: a study by the Breast International Group Brain Metastasis Task Force
- 2022
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Ingår i: ESMO Open. - : Elsevier BV. - 2059-7029. ; 7:3
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Tidskriftsartikel (refereegranskat)abstract
- Background: Carcinomatous meningitis (CM) is a severe complication of breast cancer. The Breast International Group (BIG) carried out a survey to describe the approach to CM internationally. Patients and methods: A questionnaire on the management of CM was developed by the Brain Metastases Task Force of BIG and distributed to its groups, requesting one answer per group site. Results: A total of 241 sites responded, 119 from Europe, 9 from North America, 39 from Central/South America, 58 from Asia, and 16 in Australia/New Zealand, with 24.5% being general hospitals with oncology units, 44.4% university hospitals, 22.4% oncology centers, and 8.7% private hospitals. About 56.0% of sites reported seeing <5 cases annually with 60.6% reporting no increase in the number of cases of CM recently. Nearly 63.1% of sites investigate for CM when a patient has symptoms or radiological evidence, while 33.2% investigate only for symptoms. For diagnosis, 71.8% of sites required a positive cerebrospinal fluid cytology, while magnetic resonance imaging findings were sufficient in 23.7% of sites. Roughly 97.1% of sites treat CM and 51.9% also refer patients to palliative care. Intrathecal therapy is used in 41.9% of sites, mainly with methotrexate (74.3%). As many as 20 centers have a national registry for patients with breast cancer with central nervous system metastases and of those 5 have one for CM. Most (90.9%) centers would be interested in participating in a registry as well as in studies for CM, the latter preferably (62.1%) breast cancer subtype specific. Conclusions: This is the first study to map out the approach to CM from breast cancer globally. Although guidelines with level 1 evidence are lacking, there is a high degree of homogeneity in the approach to CM globally and great interest for conducting studies in this area.
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| 23. |
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| 24. |
- de Haan, J. E. S., et al.
(författare)
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Stabilising system frequency using HVDC between the Continental European, Nordic, and Great Britain systems
- 2016
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Ingår i: Sustainable Energy, Grids and Networks. - : Elsevier. - 2352-4677. ; 5, s. 125-134
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Tidskriftsartikel (refereegranskat)abstract
- For future efficiency improvement of the frequency containment process (primary control) within European power systems, cooperation between (multiple) synchronous areas using their controllable HVDC interconnections is optioned. However, the differences in system size, HVDC interconnection capacity, and the balancing performance per individual system will have its specific system frequency effect for each different balancing cooperation concept. Consequently, without alignment on cooperation, HVDC balancing might lead to disproportional support between systems, to frequency oscillations, reserve unreliability and non-compliancy, and to network constraints. Therefore, this work assesses frequency quality and associated DC power flows for several balancing arrangements, using a developed load-frequency control model with frequency interdependency for coupled power system. For a trilateral balancing cooperation case study, it is found that certain cooperation concepts result in undesired frequency oscillation and poor frequency quality. However, cooperation where especially fast-response services are shared, such as virtual inertia, show improved system frequency performance. For the case where power imbalances are proportionately distributed among the systems, it is concluded that power transfers over HVDC interconnections are limited and additional control optimisation can be performed. Those concepts with aligned central or coordinated control show best results for a future cooperation for balancing between synchronous areas.
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| 25. |
- Dengler, Juergen, et al.
(författare)
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GrassPlot - a database of multi-scale plant diversity in Palaearctic grasslands
- 2018
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Ingår i: Phytocoenologia. - : Schweizerbart. - 0340-269X. ; 48:3, s. 331-347
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Tidskriftsartikel (refereegranskat)abstract
- GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board.
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| 26. |
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| 27. |
- Gonzalez, J. M., et al.
(författare)
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Genome analysis of the proteorhodopsin-containing marine bacterium Polaribacter sp. MED152 (Flavobacteria)
- 2008
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 105:25, s. 8724-8729
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Tidskriftsartikel (refereegranskat)abstract
- Analysis of marine cyanobacteria and proteobacteria genomes has provided a profound understanding of the life strategies of these organisms and their ecotype differentiation and metabolisms. However, a comparable analysis of the Bacteroidetes, the third major bacterioplankton group, is still lacking. In the present paper, we report on the genome of Polaribacter sp. strain MED152. On the one hand, MED152 contains a substantial number of genes for attachment to surfaces or particles, gliding motility, and polymer degradation. This agrees with the currently assumed life strategy of marine Bacteroidetes. On the other hand, it contains the proteorhoclopsin gene, together with a remarkable suite of genes to sense and respond to light, which may provide a survival advantage in the nutrient-poor sun-lit ocean surface when in search of fresh particles to colonize. Furthermore, an increase in CO2 fixation in the light suggests that the limited central metabolism is complemented by anaplerotic inorganic carbon fixation. This is mediated by a unique combination of membrane transporters and carboxylases. This suggests a dual life strategy that, if confirmed experimentally, would be notably different from what is known of the two other main bacterial groups (the autotrophic cyanobacteria and the heterotrophic proteobacteria) in the surface oceans. The Polaribacter genome provides insights into the physiological capabilities of proteorhodopsin-containing bacteria. The genome will serve as a model to study the cellular and molecular processes in bacteria that express proteorhoclopsin, their adaptation to the oceanic environment, and their role in carbon-cycling.
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| 28. |
- Goudzovski, Evgueni, et al.
(författare)
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New physics searches at kaon and hyperon factories
- 2023
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Ingår i: Reports on progress in physics (Print). - : Institute of Physics (IOP). - 0034-4885 .- 1361-6633. ; 86:1
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Forskningsöversikt (refereegranskat)abstract
- Rare meson decays are among the most sensitive probes of both heavy and light new physics. Among them, new physics searches using kaons benefit from their small total decay widths and the availability of very large datasets. On the other hand, useful complementary information is provided by hyperon decay measurements. We summarize the relevant phenomenological models and the status of the searches in a comprehensive list of kaon and hyperon decay channels. We identify new search strategies for under-explored signatures, and demonstrate that the improved sensitivities from current and next-generation experiments could lead to a qualitative leap in the exploration of light dark sectors.
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| 29. |
- Jaako, Pekka, et al.
(författare)
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eIF6 rebinding dynamically couples ribosome maturation and translation.
- 2022
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Protein synthesis is a cyclical process consisting of translation initiation, elongation, termination and ribosome recycling. The release factors SBDS and EFL1-both mutated in the leukemia predisposition disorder Shwachman-Diamond syndrome - license entry of nascent 60S ribosomal subunits into active translation by evicting the anti-association factor eIF6 from the 60S intersubunit face. We find that in mammalian cells, eIF6 holds all free cytoplasmic 60S subunits in a translationally inactive state and that SBDS and EFL1 are the minimal components required to recycle these 60S subunits back into additional rounds of translation by evicting eIF6. Increasing the dose of eIF6 in mice in vivo impairs terminal erythropoiesis by sequestering post-termination 60S subunits in the cytoplasm, disrupting subunit joining and attenuating global protein synthesis. These data reveal that ribosome maturation and recycling are dynamically coupled by a mechanism that is disrupted in an inherited leukemia predisposition disorder.
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| 30. |
- Madrigal-Gonzalez, Jaime, et al.
(författare)
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Climate reverses directionality in the richness-abundance relationship across the World's main forest biomes
- 2020
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Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- More tree species can increase the carbon storage capacity of forests (here referred to as the more species hypothesis) through increased tree productivity and tree abundance resulting from complementarity, but they can also be the consequence of increased tree abundance through increased available energy (more individuals hypothesis). To test these two contrasting hypotheses, we analyse the most plausible pathways in the richness-abundance relationship and its stability along global climatic gradients. We show that positive effect of species richness on tree abundance only prevails in eight of the twenty-three forest regions considered in this study. In the other forest regions, any benefit from having more species is just as likely (9 regions) or even less likely (6 regions) than the effects of having more individuals. We demonstrate that diversity effects prevail in the most productive environments, and abundance effects become dominant towards the most limiting conditions. These findings can contribute to refining cost-effective mitigation strategies based on fostering carbon storage through increased tree diversity. Specifically, in less productive environments, mitigation measures should promote abundance of locally adapted and stress tolerant tree species instead of increasing species richness. Correlations between tree species diversity and tree abundance are well established, but the direction of the relationship is unresolved. Here the authors use path models to estimate plausible causal pathways in the diversity-abundance relationship across 23 global forests regions, finding a lack of general support for a positive diversity-abundance relationship, which is prevalent in the most productive lands on Earth only
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| 31. |
- Sanchez, Lorena Escudero, et al.
(författare)
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Integrating Artificial Intelligence Tools in the Clinical Research Setting : The Ovarian Cancer Use Case
- 2023
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Ingår i: Diagnostics. - : MDPI. - 2075-4418. ; 13:17
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Tidskriftsartikel (refereegranskat)abstract
- Artificial intelligence (AI) methods applied to healthcare problems have shown enormous potential to alleviate the burden of health services worldwide and to improve the accuracy and reproducibility of predictions. In particular, developments in computer vision are creating a paradigm shift in the analysis of radiological images, where AI tools are already capable of automatically detecting and precisely delineating tumours. However, such tools are generally developed in technical departments that continue to be siloed from where the real benefit would be achieved with their usage. Significant effort still needs to be made to make these advancements available, first in academic clinical research and ultimately in the clinical setting. In this paper, we demonstrate a prototype pipeline based entirely on open-source software and free of cost to bridge this gap, simplifying the integration of tools and models developed within the AI community into the clinical research setting, ensuring an accessible platform with visualisation applications that allow end-users such as radiologists to view and interact with the outcome of these AI tools.
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| 32. |
- Wheeler, David C., et al.
(författare)
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The dapagliflozin and prevention of adverse outcomes in chronic kidney disease (DAPA-CKD) trial : baseline characteristics
- 2020
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Ingår i: Nephrology, Dialysis and Transplantation. - OXFORD ENGLAND : Oxford University Press (OUP). - 0931-0509 .- 1460-2385. ; 35:10, s. 1700-1711
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Tidskriftsartikel (refereegranskat)abstract
- Background. The Dapagliflozin and Prevention of Adverse outcomes in Chronic Kidney Disease (DAPA-CKD; NCT03036150) trial was designed to assess the effect of the sodium-glucose co-transporter 2 (SGLT2) inhibitor dapagliflozin on kidney and cardiovascular events in participants with CKD with and without type 2 diabetes (T2D). This analysis reports the baseline characteristics of those recruited, comparing them with those enrolled in other trials. Methods. In DAPA-CKD, 4304 participants with a urinary albumin:creatinine ratio (UACR) <= 200mg/g and estimated glomerular filtration rate (eGFR) between 25 and 75mL/min/1.73m(2) were randomized to dapagliflozin 10mg once daily or placebo. Mean eGFR was 43.1mL/min/1.73m(2) and median UACR was 949 mg/g (108mg/mmol). Results. Overall, 2906 participants (68%) had a diagnosis of T2D and of these, 396 had CKD ascribed to a cause other than diabetes. The most common causes of CKD after diabetes (n = 2510) were ischaemic/hypertensive nephropathy (n = 687) and chronic glomerulonephritis (n = 695), of which immunoglobulin A nephropathy (n = 270) was the most common. A total of 4174 participants (97%) were receiving an angiotensinconverting enzyme inhibitor or angiotensin receptor blocker, 1882 (43.7%) diuretics, 229 (5.3%) mineralocorticoid receptor antagonists and 122 (2.8%) glucagon-like peptide 1 receptor agonists. In contrast to the Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE), the DAPA-CKD trial enrolled participants with CKD due to diabetes and to causes other than diabetes. The mean eGFR of participants in the DAPA-CKD trial was 13.1mL/min/1.73m(2) lower than in CREDENCE, similar to that in the Finerenone in Reducing Kidney Failure and Disease Progression in DKD (FIDELIO-DKD) trial and the Study Of diabetic Nephropathy with AtRasentan (SONAR). Conclusions. Participants with a wide range of underlying kidney diseases receiving renin-angiotensin system blocking therapy have been enrolled in the DAPA-CKD trial. The trial will examine the efficacy and safety of dapagliflozin in participants with CKD Stages 2-4 and increased albuminuria, with and without T2D.
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| 33. |
- Batlle, X., et al.
(författare)
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Quantitative x-ray photoelectron spectroscopy study of Al/AlOx bilayers
- 2002
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 91:12, s. 10163-10168
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Tidskriftsartikel (refereegranskat)abstract
- An x-ray photoelectron spectroscopy (XPS) analysis of Nb/Al wedge bilayers, oxidized by both plasma and natural oxidation, is reported. The main goal is to show that the oxidation state-i.e., O:(oxidize)Al ratio-, structure and thickness of the surface oxide layer, as well as the thickness of the metallic Al leftover, as functions of the oxidation procedure, can be quantitatively evaluated from the XPS spectra. This is relevant to the detailed characterization of the insulating barriers in (magnetic) tunnel junctions.
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| 34. |
- Batlle, X., et al.
(författare)
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The oxidation state at tunnel junction interfaces
- 2003
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Ingår i: Journal of Magnetism and Magnetic Materials. - 0304-8853 .- 1873-4766. ; 260:02-jan, s. 78-83
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Tidskriftsartikel (refereegranskat)abstract
- The oxidation state at the interfaces of Nb/Al-AlOx/Pb junctions is discussed. Conductance-voltage curves below and above the superconducting temperature suggest tunneling conduction, while X-ray photoelectron spectroscopy shows the existence of a thin AlOx layer at the Nb/Al interface. We demonstrate that at the usual 10(-7) Torr range of base pressures in the sputtering chamber, this is due to the time elapsed between the deposition of the Nb and Al bottom layers, in both Nb/Al-AlOx/Pb tunnel junctions and Nb/Al bilayers. We also give some direct evidence of the oxidation of the top Pb electrode on the Nb electrode surface. Such oxidation probably occurs at the pinholes of the intermediate Al-AlOx layer of the tunnel junctions, as a consequence of the oxidation state at the Nb/Al interface, which helps to avoid barrier shorts and enhances the quality of the tunnel barrier. We therefore suggest that there is oxide formation in other places besides where there is an actual oxide deposited. This is relevant for the performance of magnetic tunnel junctions since in most tunneling studies it is assumed that once the oxide is deposited, that is the only place where there is an oxide. This is also a very general statement applicable to thin film systems.
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| 35. |
- Calatayud, Joaquín, et al.
(författare)
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Positive associations among rare species and their persistence in ecological assemblages
- 2020
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Ingår i: Nature Ecology & Evolution. - : Nature Publishing Group. - 2397-334X. ; 4:1, s. 40-45
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Tidskriftsartikel (refereegranskat)abstract
- According to the competitive exclusion principle, species with low competitive abilities should be excluded by more efficient competitors; yet, they generally remain as rare species. Here, we describe the positive and negative spatial association networks of 326 disparate assemblages, showing a general organization pattern that simultaneously supports the primacy of competition and the persistence of rare species. Abundant species monopolize negative associations in about 90% of the assemblages. On the other hand, rare species are mostly involved in positive associations, forming small network modules. Simulations suggest that positive interactions among rare species and microhabitat preferences are the most probable mechanisms underpinning this pattern and rare species persistence. The consistent results across taxa and geography suggest a general explanation for the maintenance of biodiversity in competitive environments. Analysing spatial association networks among >300 terrestrial and aquatic assemblages, the authors find that the majority of negative associations involve abundant species. In contrast, rare species form mostly positive associations, potentially explaining their persistence in natural communities.
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| 36. |
- Castaño Díaz, Carlos Mauricio, 1985, et al.
(författare)
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Mental Health of People Under Isolation During the covid-19 Outbreak: An Exploratory Study
- 2022
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Ingår i: Revista Colombiana de Psicologia. - : Universidad Nacional de Colombia. - 2344-8644 .- 0121-5469. ; 31:2, s. 27-43
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Tidskriftsartikel (refereegranskat)abstract
- We conducted an exploratory study using a survey inquiring on seven topics on how people were reacting to the covid-19 pandemic of 2020 aiming to trace a map of symptoms and feelings related to mental health and isolation. 1785 people participated in the survey. Additionally, we applied two psychological scales to analyze depression and stress (prevalent in previous studies). We found that people in isolation during the pandemic presented symptoms related to dissociative disorders, negative affect, and anxiety syndrome. Also, depression and stress had a high prevalence compared to the average rates indicated by the World Health Organisation and the Colombian Ministry of Health. The results indicated an association between depression and stress and being previously diagnosed with a mental health problem, and job and financial situation. Our results highlight the need to design prevention and intervention programmes to reduce the negative consequences of isolation. © 2022 Universidad Nacional de Colombia. All rights reserved.
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| 37. |
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| 38. |
- Escudero, M. J., et al.
(författare)
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Development and performance characterisation of new electrocatalysts for PEMFC
- 2002
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Ingår i: Journal of Power Sources. - 0378-7753 .- 1873-2755. ; 106:1-2, s. 206-214
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Konferensbidrag (refereegranskat)abstract
- New electrocatalysts based on Pt, Pt-Ru and Pt-Pd have been prepared by the microemulsion method. This method allows the production of a very narrow size distribution of metal particles, with an average size smaller than that of conventional electrocatalysts prepared by impregnation. Eight membrane electrode assemblies (MEAs) with an active surface area of 50 cm(2) were characterised in a single fuel cell. The MEAs consist of Nation 117 as membrane and a commercial electrocatalyst (40% Pt/C from E-TEK) on the cathode side, Four MEAs have electrocatalysts prepared by the microemulsion technique and the other four have commercial electrocatalysts on the anode side. The performance of the eight MEAs was evaluated by measuring the fuel cell polarisation curves and the internal resistance with H-2/O-2 and H-2/air, at 60 T and pressure in the range from I to 3 bar. The MEAs with the electrocatalysts prepared by microemulsion showed a performance comparable to that of the MEAs with commercial electrocatalysts. The satisfactory results obtained show that microemulsion is a promising method for the preparation of electrocatalysts for fuel cells. Further effort will be devoted to the optimisation of the method, mainly, the deposition of the metal particles on the carbon support, which it is expected to enhance the fuel cell performance.
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| 39. |
- Escudero-Martinez, I, et al.
(författare)
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Association of statin pre-treatment with baseline stroke severity and outcome in patients with acute ischemic stroke and received reperfusion treatment: An observational study
- 2023
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Ingår i: International journal of stroke : official journal of the International Stroke Society. - : SAGE Publications. - 1747-4949. ; 18:2, s. 201-207
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Tidskriftsartikel (refereegranskat)abstract
- Statins have an important role in stroke prevention, especially in high-risk populations and may also affect the initial stroke severity and outcomes in patients taking them before an ischemic stroke. Aims: Our aim was to evaluate the association of statin pre-treatment with the severity in acute ischemic stroke (AIS). Methods: We analyzed AIS patients received intravenous thrombolysis (IVT) and/or endovascular thrombectomy (EVT) and recorded in the SITS International Thrombolysis and Thrombectomy Registry from 2011 to 2017. We identified patients with statin information at baseline. The primary outcome was baseline National Institutes of Health Stroke Scale (NIHSS) score. Secondary outcomes were NIHSS score at 24 h, symptomatic intracerebral hemorrhage (SICH) and functional outcome at 90 days after acute intervention. Multivariable linear and logistic regression and propensity score matching (PSM) was used to quantify the effect of statin pre-treatment. Results: Of 93,849 patients, 23,651 (25.2%) were treated with statins prior the AIS. Statin pre-treatment group was older and had higher comorbidity. Median NIHSS at baseline was similar between groups. In the adjusted and PSM analysis, statin pre-treatment was inversely associated with baseline NIHSS (odds ratio (OR) = 0.77, 95% confidence interval (CI) = 0.6–0.99 and OR for PSM 0.73, 95% CI = 0.54–0.99, p = 0.004) and independently associated with mild stroke defined as NIHSS ⩽8 in adjusted and PSM analysis (OR = 1.21, 95% CI = 1.1–1.34, p < 0.001 and OR for PSM 1.17, 95% CI = 1.05–1.31, p = 0.007). Regarding secondary outcomes, there were no differences in functional outcomes, death nor SICH rates between groups. Conclusion: Prior treatment with statins was associated with lower NIHSS at baseline. However, this association did not translate into any difference regarding functional outcome at 90 days. No association was found regarding SICH. These findings indicate the need of further studies to assess the effect on statin pre-treatment on initial stroke severity.
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| 40. |
- Escudero-Martinez, I, et al.
(författare)
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Cerebral Edema in Patients with severe Hemispheric Syndrome: Incidence, Risk Factors, and Outcomes-Data from SITS-ISTR
- 2023
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Ingår i: Journal of stroke. - : Korean Stroke Society. - 2287-6391 .- 2287-6405. ; 25:1, s. 101-
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Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose Cerebral edema (CED) in ischemic stroke can worsen prognosis and about 70% of patients who develop severe CED die if treated conservatively. We aimed to describe incidence, risk factors and outcomes of CED in patients with extensive ischemia.Methods Oservational study based on Safe Implementation of Treatments in Stroke-International Stroke Treatment Registry (2003–2019). Severe hemispheric syndrome (SHS) at baseline and persistent SHS (pSHS) at 24 hours were defined as National Institutes of Health Stroke Score (NIHSS) >15. Outcomes were moderate/severe CED detected by neuroimaging, functional independence (modified Rankin Scale 0–2) and death at 90 days.Results Patients (n=8,560) presented with SHS and developed pSHS at 24 hours; 82.2% received intravenous thrombolysis (IVT), 10.5% IVT+thrombectomy, and 7.3% thrombectomy alone. Median age was 77 and NIHSS 21. Of 7,949 patients with CED data, 3,780 (47.6%) had any CED and 2,297 (28.9%) moderate/severe CED. In the multivariable analysis, age <50 years (relative risk [RR], 1.56), signs of acute infarct (RR, 1.29), hyperdense artery sign (RR, 1.39), blood glucose >128.5 mg/dL (RR, 1.21), and decreased level of consciousness (RR, 1.14) were associated with moderate/severe CED (for all P<0.05). Patients with moderate/severe CED had lower odds to achieve functional Independence (adjusted odds ratio [aOR], 0.35; 95% confidence interval [CI], 0.23 to 0.55) and higher odds of death at 90 days (aOR, 2.54; 95% CI, 2.14 to 3.02).Conclusions In patients with extensive ischemia, the most important predictors for moderate/ severe CED were age <50, high blood glucose, signs of acute infarct, hyperdense artery on baseline scans, and decreased level of consciousness. CED was associated with worse functional outcome and a higher risk of death at 3 months.
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| 41. |
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| 42. |
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| 43. |
- Ghersi, Marisa Soledad, et al.
(författare)
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Ghrelin inhibited serotonin release from hippocampal slices
- 2011
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Ingår i: Peptides. - : Elsevier BV. - 0196-9781 .- 1873-5169. ; 32:11, s. 2367-2371
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Tidskriftsartikel (refereegranskat)abstract
- Ghrelin (Ghr) is a peptide produced peripherally and centrally. It participates in the modulation of different biological processes. In our laboratory we have shown that (a) Ghr administration, either intracerebroventricular or directly into the hippocampus enhanced memory consolidation in a step down test in rats (b) the effect of Ghr upon memory decreases in animals pretreated with a serotonin (5-HT) reuptake inhibitor, Fluoxetine, suggesting that Ghr effects in the hippocampus could be related to the availability of 5-HT. It has been demonstrated that Ghr inhibits 5-HT release from rat hypothalamic synaptosomes. Taking in mint these evidences, we studied the release of radioactive 5-HT to the superfusion medium from hippocampal slices treated with two doses of Ghr (0.3 and 3 nm/mu l). Ghr inhibited significantly the 5-HT release in relation to those superfused with artificial cerebrospinal fluid (ACSF) (H = 9.48, df = 2, p <= 0.05). In another set of experiments. Ghr was infused into the CA1 area of hippocampus of the rats immediately after training in the step down test and the 5-HT release from slices was studied 24 h after Ghr injection showing that in this condition also the 5-HT release was inhibited (H = 11.72, df = 1, p < 0.05). In conclusion, results provide additional evidence about the neurobiological bases of Ghr action in hippocampus.
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| 44. |
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| 45. |
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| 46. |
- Ruiz-Martinez, Jorge, et al.
(författare)
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Prevalence and Genetic Diversity of Avipoxvirus in House Sparrows in Spain
- 2016
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:12
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Tidskriftsartikel (refereegranskat)abstract
- Avipoxvirus (APV) is a fairly common virus affecting birds that causes morbidity and mortality in wild and captive birds. We studied the prevalence of pox-like lesions and genetic diversity of APV in house sparrows (Passer domesticus) in natural, agricultural and urban areas in southern Spain in 2013 and 2014 and in central Spain for 8 months (2012-2013). Overall, 3.2% of 2,341 house sparrows visually examined in southern Spain had cutaneous lesions consistent with avian pox. A similar prevalence (3%) was found in 338 birds from central Spain. Prevalence was higher in hatch-year birds than in adults. We did not detect any clear spatial or temporal patterns of APV distribution. Molecular analyses of poxvirus-like lesions revealed that 63% of the samples were positive. Molecular and phylogenetic analyses of 29 DNA sequences from the fpv167 gene, detected two strains belonging to the canarypox clade (subclades B1 and B2) previously found in Spain. One of them appears predominant in Iberia and North Africa and shares 70% similarity to fowlpox and canarypox virus. This APV strain has been identified in a limited number of species in the Iberian Peninsula, Morocco and Hungary. The second one has a global distribution and has been found in numerous wild bird species around the world. To our knowledge, this represents the largest study of avian poxvirus disease in the broadly distributed house sparrow and strongly supports the findings that Avipox prevalence in this species in South and central Spain is moderate and the genetic diversity low.
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| 47. |
- Schiller, Frederik, et al.
(författare)
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Catalytic Oxidation of Carbon Monoxide on a Curved Pd Crystal : Spatial Variation of Active and Poisoning Phases in Stationary Conditions
- 2018
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 1520-5126 .- 0002-7863. ; 140:47, s. 16245-16252
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Tidskriftsartikel (refereegranskat)abstract
- Understanding nanoparticle catalysis requires novel approaches in which adjoining crystal orientations can be studied under the same reactive conditions. Here we use a curved palladium crystal and near-ambient pressure X-ray photoemission spectroscopy to characterize chemical species during the catalytic oxidation of CO in a whole set of surfaces vicinal to the (111) direction simultaneously. By stabilizing the reaction at fixed temperatures around the ignition point, we observe a strong variation of the catalytic activity across the curved surface. Such spatial modulation of the reaction stage is straightforwardly mapped through the photoemission signal from active oxygen species and poisoning CO, which are shown to coexist in a transient regime that depends on the vicinal angle. Line-shape analysis and direct comparison with ultrahigh vacuum experiments help identifying and quantifying all such surface species, allowing us to reveal the presence of surface oxides during reaction ignition and cooling-off.
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| 48. |
- Siahrostami, Samira, 1982, et al.
(författare)
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Enabling direct H2O2 production through rational electrocatalyst design
- 2013
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Ingår i: Nature Materials. - : Springer Science and Business Media LLC. - 1476-4660 .- 1476-1122. ; 12:12, s. 1137-1143
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Tidskriftsartikel (refereegranskat)abstract
- Future generations require more efficient and localized processes for energy conversion and chemical synthesis. The continuous on-site production of hydrogen peroxide would provide an attractive alternative to the present state-of-the-art, which is based on the complex anthraquinone process. The electrochemical reduction of oxygen to hydrogen peroxide is a particularly promising means of achieving this aim. However, it would require active, selective and stable materials to catalyse the reaction. Although progress has been made in this respect, further improvements through the development of new electrocatalysts are needed. Using density functional theory calculations, we identify Pt-Hg as a promising candidate. Electrochemical measurements on Pt-Hg nanoparticles show more than an order of magnitude improvement in mass activity, that is, Ag-1 precious metal, for H2O2 production, over the best performing catalysts in the literature.
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| 49. |
- Sivan, Pramod, 1984-, et al.
(författare)
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Unraveling the unique structural motifs of glucuronoxylan from hybrid aspen wood
- 2024
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Ingår i: Carbohydrate Polymers. - : Elsevier. - 0144-8617 .- 1879-1344. ; 343
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Tidskriftsartikel (refereegranskat)abstract
- Xylan is a fundamental structural polysaccharide in plant secondary cell walls and a valuable resource for biorefinery applications. Deciphering the molecular motifs of xylans that mediate their interaction with cellulose and lignin is fundamental to understand the structural integrity of plant cell walls and to design lignocellulosic materials. In the present study, we investigated the pattern of acetylation and glucuronidation substitution in hardwood glucuronoxylan (GX) extracted from aspen wood using subcritical water and alkaline conditions. Enzymatic digestions of GX with β-xylanases from glycosyl hydrolase (GH) families GH10, GH11 and GH30 generated xylo-oligosaccharides with controlled structures amenable for mass spectrometric glycan sequencing. We identified the occurrence of intramolecular motifs in aspen GX with block repeats of even glucuronidation (every 2 xylose units) and consecutive glucuronidation, which are unique features for hardwood xylans. The acetylation pattern of aspen GX shows major domains with evenly-spaced decorations, together with minor stretches of highly acetylated domains. These heterogenous patterns of GX can be correlated with its extractability and with its potential interaction with lignin and cellulose. Our study provides new insights into the molecular structure of xylan in hardwood species, which has fundamental implications for overcoming lignocellulose recalcitrance during biochemical conversion.
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