| 1. |
- Tabiri, S, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 2. |
- Bravo, L, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 3. |
- Glasbey, JC, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 4. |
- Khatri, C, et al.
(författare)
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Outcomes after perioperative SARS-CoV-2 infection in patients with proximal femoral fractures: an international cohort study
- 2021
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Ingår i: BMJ open. - : BMJ. - 2044-6055. ; 11:11, s. e050830-
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Tidskriftsartikel (refereegranskat)abstract
- Studies have demonstrated high rates of mortality in people with proximal femoral fracture and SARS-CoV-2, but there is limited published data on the factors that influence mortality for clinicians to make informed treatment decisions. This study aims to report the 30-day mortality associated with perioperative infection of patients undergoing surgery for proximal femoral fractures and to examine the factors that influence mortality in a multivariate analysis.SettingProspective, international, multicentre, observational cohort study.ParticipantsPatients undergoing any operation for a proximal femoral fracture from 1 February to 30 April 2020 and with perioperative SARS-CoV-2 infection (either 7 days prior or 30-day postoperative).Primary outcome30-day mortality. Multivariate modelling was performed to identify factors associated with 30-day mortality.ResultsThis study reports included 1063 patients from 174 hospitals in 19 countries. Overall 30-day mortality was 29.4% (313/1063). In an adjusted model, 30-day mortality was associated with male gender (OR 2.29, 95% CI 1.68 to 3.13, p<0.001), age >80 years (OR 1.60, 95% CI 1.1 to 2.31, p=0.013), preoperative diagnosis of dementia (OR 1.57, 95% CI 1.15 to 2.16, p=0.005), kidney disease (OR 1.73, 95% CI 1.18 to 2.55, p=0.005) and congestive heart failure (OR 1.62, 95% CI 1.06 to 2.48, p=0.025). Mortality at 30 days was lower in patients with a preoperative diagnosis of SARS-CoV-2 (OR 0.6, 95% CI 0.6 (0.42 to 0.85), p=0.004). There was no difference in mortality in patients with an increase to delay in surgery (p=0.220) or type of anaesthetic given (p=0.787).ConclusionsPatients undergoing surgery for a proximal femoral fracture with a perioperative infection of SARS-CoV-2 have a high rate of mortality. This study would support the need for providing these patients with individualised medical and anaesthetic care, including medical optimisation before theatre. Careful preoperative counselling is needed for those with a proximal femoral fracture and SARS-CoV-2, especially those in the highest risk groups.Trial registration numberNCT04323644
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| 5. |
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| 6. |
- In ’t Veld, Sjors G.J.G., et al.
(författare)
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Detection and localization of early- and late-stage cancers using platelet RNA
- 2022
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Ingår i: Cancer Cell. - : Elsevier. - 1535-6108 .- 1878-3686. ; 40:9, s. 999-1009.e6
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Tidskriftsartikel (refereegranskat)abstract
- Cancer patients benefit from early tumor detection since treatment outcomes are more favorable for less advanced cancers. Platelets are involved in cancer progression and are considered a promising biosource for cancer detection, as they alter their RNA content upon local and systemic cues. We show that tumor-educated platelet (TEP) RNA-based blood tests enable the detection of 18 cancer types. With 99% specificity in asymptomatic controls, thromboSeq correctly detected the presence of cancer in two-thirds of 1,096 blood samples from stage I–IV cancer patients and in half of 352 stage I–III tumors. Symptomatic controls, including inflammatory and cardiovascular diseases, and benign tumors had increased false-positive test results with an average specificity of 78%. Moreover, thromboSeq determined the tumor site of origin in five different tumor types correctly in over 80% of the cancer patients. These results highlight the potential properties of TEP-derived RNA panels to supplement current approaches for blood-based cancer screening.
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| 7. |
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| 8. |
- Householder, John Ethan, et al.
(författare)
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One sixth of Amazonian tree diversity is dependent on river floodplains
- 2024
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Ingår i: NATURE ECOLOGY & EVOLUTION. - 2397-334X.
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Tidskriftsartikel (refereegranskat)abstract
- Amazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region's floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon's tree diversity and its function.
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| 9. |
- Bentley, Blair P., et al.
(författare)
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Divergent sensory and immune gene evolution in sea turtles with contrasting demographic and life histories
- 2023
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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 (PNAS). - 0027-8424 .- 1091-6490. ; 120:7
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Tidskriftsartikel (refereegranskat)abstract
- Sea turtles represent an ancient lineage of marine vertebrates that evolved from terrestrial ancestors over 100 Mya. The genomic basis of the unique physiological and ecological traits enabling these species to thrive in diverse marine habitats remains largely unknown. Additionally, many populations have drastically declined due to anthropogenic activities over the past two centuries, and their recovery is a high global conservation priority. We generated and analyzed high-quality reference genomes for the leatherback (Dermochelys coriacea) and green (Chelonia mydas) turtles, representing the two extant sea turtle families. These genomes are highly syntenic and homologous, but localized regions of noncollinearity were associated with higher copy numbers of immune, zinc-finger, and olfactory receptor (OR) genes in green turtles, with ORs related to waterborne odorants greatly expanded in green turtles. Our findings suggest that divergent evolution of these key gene families may underlie immunological and sensory adaptations assisting navigation, occupancy of neritic versus pelagic environments, and diet specialization. Reduced collinearity was especially prevalent in microchromosomes, with greater gene content, heterozygosity, and genetic distances between species, supporting their critical role in vertebrate evolutionary adaptation. Finally, diversity and demographic histories starkly contrasted between species, indicating that leatherback turtles have had a low yet stable effective population size, exhibit extremely low diversity compared with other reptiles, and harbor a higher genetic load compared with green turtles, reinforcing concern over their persistence under future climate scenarios. These genomes provide invaluable resources for advancing our understanding of evolution and conservation best practices in an imperiled vertebrate lineage.
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| 10. |
- Luize, Bruno Garcia, et al.
(författare)
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Geography and ecology shape the phylogenetic composition of Amazonian tree communities
- 2024
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Ingår i: JOURNAL OF BIOGEOGRAPHY. - 0305-0270 .- 1365-2699.
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and v & aacute;rzea forest types, the phylogenetic composition varies by geographic region, but the igap & oacute; and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R-2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R-2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions.
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| 11. |
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| 12. |
- ter Steege, Hans, et al.
(författare)
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Mapping density, diversity and species-richness of the Amazon tree flora
- 2023
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Ingår i: COMMUNICATIONS BIOLOGY. - 2399-3642. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution. A study mapping the tree species richness in Amazonian forests shows that soil type exerts a strong effect on species richness, probably caused by the areas of these forest types. Cumulative water deficit, tree density and temperature seasonality affect species richness at a regional scale.
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| 13. |
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| 14. |
- Barnett, Ross, et al.
(författare)
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Genomic Adaptations and Evolutionary History of the Extinct Scimitar-Toothed Cat, Homotherium latidens
- 2020
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Ingår i: Current Biology. - 0960-9822 .- 1879-0445.
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Tidskriftsartikel (refereegranskat)abstract
- Summary Homotherium was a genus of large-bodied scimitar-toothed cats, morphologically distinct from any extant felid species, that went extinct at the end of the Pleistocene [1, 2, 3, 4]. They possessed large, saber-form serrated canine teeth, powerful forelimbs, a sloping back, and an enlarged optic bulb, all of which were key characteristics for predation on Pleistocene megafauna [5]. Previous mitochondrial DNA phylogenies suggested that it was a highly divergent sister lineage to all extant cat species [6, 7, 8]. However, mitochondrial phylogenies can be misled by hybridization [9], incomplete lineage sorting (ILS), or sex-biased dispersal patterns [10], which might be especially relevant for Homotherium since widespread mito-nuclear discrepancies have been uncovered in modern cats [10]. To examine the evolutionary history of Homotherium, we generated a ∼7x nuclear genome and a ∼38x exome from H. latidens using shotgun and target-capture sequencing approaches. Phylogenetic analyses reveal Homotherium as highly divergent (∼22.5 Ma) from living cat species, with no detectable signs of gene flow. Comparative genomic analyses found signatures of positive selection in several genes, including those involved in vision, cognitive function, and energy consumption, putatively consistent with diurnal activity, well-developed social behavior, and cursorial hunting [5]. Finally, we uncover relatively high levels of genetic diversity, suggesting that Homotherium may have been more abundant than the limited fossil record suggests [3, 4, 11, 12, 13, 14]. Our findings complement and extend previous inferences from both the fossil record and initial molecular studies, enhancing our understanding of the evolution and ecology of this remarkable lineage.
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| 15. |
- Cooper, Declan L.M., et al.
(författare)
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Consistent patterns of common species across tropical tree communities
- 2024
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Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 625:7996, s. 728-734
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Tidskriftsartikel (refereegranskat)abstract
- Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations 1–6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories 7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.
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| 16. |
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| 17. |
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| 18. |
- Fernandes, C., et al.
(författare)
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New deep eutectic solvent assisted extraction of highly pure lignin from maritime pine sawdust (Pinus pinaster Ait.)
- 2021
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Ingår i: International Journal of Biological Macromolecules. - : Elsevier BV. - 0141-8130 .- 1879-0003. ; 177, s. 294-305
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Tidskriftsartikel (refereegranskat)abstract
- Lignocellulosic biomass is a renewable and sustainable feedstock, mainly composed of cellulose, hemicellulose, and lignin. Lignin, as the most abundant natural aromatic polymer occurring on Earth, has great potential to produce value-added products. However, the isolation of highly pure lignin from biomass requires the use of efficient methods during lignocellulose fractionation. Therefore, in this work, novel acidic deep eutectic solvents (DESs) were prepared, characterized and screened for lignin extraction from maritime pine wood (Pinus pinaster Ait.) sawdust. The use of cosolvents and the development of new DES were also evaluated regarding their extraction and selectivity performance. The results show that an 1 h extraction process at 175 °C, using a novel DES composed of lactic acid, tartaric acid and choline chloride, named Lact:Tart:ChCl, in a molar ratio of 4:1:1, allows the recovery of 95 wt% of the total lignin present in pine biomass with a purity of 89 wt%. Such superior extraction of lignin with remarkable purity using a “green” solvent system makes this process highly appealing for future large-scale applications.
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| 19. |
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| 20. |
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| 21. |
- Marote, Ana, et al.
(författare)
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Cellular Aging Secretes : a Comparison of Bone-Marrow-Derived and Induced Mesenchymal Stem Cells and Their Secretome Over Long-Term Culture
- 2023
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Ingår i: Stem Cell Reviews and Reports. - : Springer Science and Business Media LLC. - 2629-3269 .- 2629-3277. ; 19:1, s. 248-263
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Tidskriftsartikel (refereegranskat)abstract
- Mesenchymal stem cells (MSCs) hold promising therapeutic potential in several clinical applications, mainly due to their paracrine activity. The implementation of future secretome-based therapeutic strategies requires the use of easily accessible MSCs sources that provide high numbers of cells with homogenous characteristics. MSCs obtained from induced pluripotent stem cells (iMSCs) have been put forward as an advantageous alternative to the gold-standard tissue sources, such as bone marrow (BM-MSCs). In this study, we aimed at comparing the secretome of BM-MSCs and iMSCs over long-term culture. For that, we performed a broad characterization of both sources regarding their identity, proteomic secretome analysis, as well as replicative senescence and associated phenotypes, including its effects on MSCs secretome composition and immunomodulatory action. Our results evidence a rejuvenated phenotype of iMSCs, which is translated into a superior proliferative capacity before the induction of replicative senescence. Despite this significant difference between iMSCs and BM-MSCs proliferation, both untargeted and targeted proteomic analysis revealed a similar secretome composition for both sources in pre-senescent and senescent states. These results suggest that shifting from the use of BM-MSCs to a more advantageous source, like iMSCs, may yield similar therapeutic effects as identified over the past years for this gold-standard MSC source. Graphical Abstract: [Figure not available: see fulltext.].
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| 22. |
- Melro, Elodie, et al.
(författare)
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Dissolution of kraft lignin in alkaline solutions
- 2020
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Ingår i: International Journal of Biological Macromolecules. - : Elsevier BV. - 0141-8130 .- 1879-0003. ; 148, s. 688-695
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Tidskriftsartikel (refereegranskat)abstract
- Lignins are among the most abundant renewable resources on the planet. However, their application is limited by the lack of efficient dissolution and extraction methodologies. In this work, a systematic and quantitative analysis of the dissolution efficiency of different alkaline-based aqueous systems (i.e. lithium hydroxide, LiOH; sodium hydroxide, NaOH; potassium hydroxide, KOH; cuprammonium hydroxide, CuAOH; tetrapropylammonium hydroxide, TPAOH and tetrabutylammonium hydroxide, TBAOH) is reported, for the first time, for kraft lignin. Phase maps were determined for all systems and lignin solubility was found to decrease in the following order: LiOH > NaOH > KOH > CuAOH > TPAOH > TBAOH, thus suggesting that the size of the cation plays an important role on its solubility. The π∗ parameter has an opposite trend to the solubility, supporting the idea that cations of smaller size favor lignin solubility. Dissolution was observed to increase exponentially above pH 9–10 being the LiOH system the most efficient. The soluble and insoluble fractions of lignin in 0.1 M NaOH were collected and analyzed by several techniques. Overall, data suggests a greater amount of simple aromatic compounds, preferentially containing sulfur, in the soluble fraction while the insoluble fraction is very similar to the native kraft lignin.
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| 23. |
- Melro, E., et al.
(författare)
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Engineering novel phenolic foams with lignin extracted from pine wood residues via a new levulinic-acid assisted process
- 2023
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Ingår i: International Journal of Biological Macromolecules. - : Elsevier. - 0141-8130 .- 1879-0003. ; 248
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Tidskriftsartikel (refereegranskat)abstract
- Phenolic foams are typically produced from phenolic resins, using phenol and formaldehyde precursors. Therefore, common phenolic foams are non-sustainable, comprising growing environmental, health, and economic concerns. In this work, lignin extracted from pine wood residues using a “green” levulinic acid-based solvent, was used to partially substitute non-sustainable phenol. The novel engineered foams were systematically compared to foams composed of different types of commercially available technical lignins. Different features were analyzed, such as foam density, microstructure (electron microscopy), surface hydrophilicity (contact angle), chemical grafting (infrared spectroscopy) and mechanical and thermal features. Overall, it was observed that up to 30 wt% of phenol can be substituted by the new type of lignin, without compromising the foam properties. This work provides a new insights on the development of novel lignin-based foams as a very promising sustainable and renewable alternative to petrol-based counterparts.
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| 24. |
- Melro, Elodie, et al.
(författare)
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Enhancing lignin dissolution and extraction : The effect of surfactants
- 2021
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Ingår i: Polymers. - : MDPI AG. - 2073-4360. ; 13:5
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Tidskriftsartikel (refereegranskat)abstract
- The dissolution and extraction of lignin from biomass represents a great challenge due to the complex structure of this natural phenolic biopolymer. In this work, several surfactants (i.e., non-ionic, anionic, and cationic) were used as additives to enhance the dissolution efficiency of model lignin (kraft) and to boost lignin extraction from pine sawdust residues. To the best of our knowledge, cationic surfactants have never been systematically used for lignin dissolution. It was found that ca. 20 wt.% of kraft lignin is completely solubilized using 1 mol L−1 octyltrimethylammo-nium bromide aqueous solution. A remarkable dissolution efficiency was also obtained using 0.5 mol L−1 polysorbate 20. Furthermore, all surfactants used increased the lignin extraction with formic acid, even at low concentrations, such as 0.01 and 0.1 mol L−1. Higher concentrations of cationic surfactants improve the extraction yield but the purity of extracted lignin decreases.
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| 25. |
- Melro, Elodie, et al.
(författare)
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Levulinic acid : A novel sustainable solvent for lignin dissolution
- 2020
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Ingår i: International Journal of Biological Macromolecules. - : Elsevier BV. - 0141-8130 .- 1879-0003. ; 164, s. 3454-3461
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Tidskriftsartikel (refereegranskat)abstract
- Lignin is a natural, renewable resource with potential to be used in biomaterials. Due to its complex structure, its efficient dissolution is still challenging, which hinders its applicability at large scale. This challenge become harder considering the current need of sustainable and environmentally friendly solvents. To the best of our knowledge, this work reports for the first time the dissolution of kraft lignin in levulinic acid, a “green” solvent, and compares its efficiency with common carboxylic acids and sulfuric acid. It has been found that levulinic acid has a high capacity to dissolve kraft lignin at room temperature (40 wt% solubility), and it efficiency is not compromised when diluting the acid with water (up to 40 wt% water content). The Kamlet-Taft π⁎ parameter of the different acidic solvents was estimated and found to correlate well with their solubility performance. Lignins previously dissolved in levulinic and formic acids were selected to be regenerated and minor differences were found in thermal stability and morphological structure, when compared to native kraft lignin. However, an increase in the content of the carbonyl groups in the regenerated lignin material was observed.
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| 26. |
- Melro, Elodie, et al.
(författare)
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Levulinic Acid-Based "Green" Solvents for Lignocellulose Fractionation : On the Superior Extraction Yield and Selectivity toward Lignin
- 2023
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Ingår i: Biomacromolecules. - : American Chemical Society (ACS). - 1525-7797 .- 1526-4602. ; 24:7, s. 3094-3104
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Tidskriftsartikel (refereegranskat)abstract
- The high potential use of lignin in novel biomaterialsand chemicalsrepresents an important opportunity for the valorization of the mostabundant natural resource of aromatic molecules. From an environmentalperspective, it is highly desirable replacing the hazardous methodscurrently used to extract lignin from lignocellulosic biomass anddevelop more sustainable and environmentally friendly approaches.Therefore, in this work, levulinic acid (a "green" solventobtained from biomass) was successfully used, for the first time,to selectively extract high-quality lignin from pine wood sawdustresidues at 200 degrees C for 6 h (at atmospheric pressure). Moreover,the addition of catalytic concentrations of inorganic acids (i.e.,H2SO4 or HCl) was found to substantially reducethe temperature and reaction times needed (i.e., 140 degrees C, 2 h)for complete lignin extraction without compromising its purity. NMRdata suggests that condensed OH structures and acidic groups are presentin the lignin following extraction. Levulinic acid can be easily recycledand efficiently reused several times without affecting its performance.Furthermore, excellent solvent reusability and performance of extractionof other wood residues has been successfully demonstrated, thus makingthe developed levulinic acid-based procedure highly appealing andpromising to replace the traditional less sustainable methodologies.
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| 27. |
- Melro, E., et al.
(författare)
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On the Development of Phenol-Formaldehyde Resins Using a New Type of Lignin Extracted from Pine Wood with a Levulinic-Acid Based Solvent
- 2022
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Ingår i: Molecules. - : MDPI AG. - 1431-5157 .- 1420-3049. ; 27:9
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Tidskriftsartikel (refereegranskat)abstract
- Resole resins have many applications, especially for foam production. However, the use of phenol, a key ingredient in resoles, has serious environmental and economic disadvantages. In this work, lignin extracted from pine wood using a “green” solvent, levulinic acid, was used to partially replace the non-sustainable phenol. The physicochemical properties of this novel resin were compared with resins composed of different types of commercial lignins. All resins were optimized to keep their free formaldehyde content below 1 wt%, by carefully adjusting the pH of the mixture. Substitution of phenol with lignin generally increases the viscosity of the resins, which is further increased with the lignin mass fraction. The addition of lignin decreases the kinetics of gelification of the resin. The type and amount of lignin also affect the thermal stability of the resins. It was possible to obtain resins with higher thermal stability than the standard phenol-formaldehyde resins without lignin. This work provides new insights regarding the development of lignin-based resoles as a very promising sustainable alternative to petrol-based resins.
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| 28. |
- Melro, E., et al.
(författare)
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Poly(butylene succinate)-Based Composites with Technical and Extracted Lignins from Wood Residues
- 2024
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Ingår i: ACS Applied Polymer Materials. - : American Chemical Society (ACS). - 2637-6105. ; 6:2, s. 1169-1181
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Tidskriftsartikel (refereegranskat)abstract
- Poly(butylene succinate) (PBS) has been drawing attention as a reliable biodegradable and sustainable alternative to synthetic petroleum-based polymers. In this study, PBS-lignin composites were developed using a recently extracted lignin (LA-lignin) from pine wood residues employing an innovative sustainable approach. These composites were systematically compared with PBS-based composites formed with commonly used technical lignins. The molecular weight of the lignins was evaluated, along with various structural and performance-related properties. The LA-lignin/PBS composites display a remarkably low water solubility (ca. < 2%), water uptake (ca. 100°). Moreover, the rigidity and thermal stability of the LA-lignin-PBS composites were higher than those of the systems formed with technical lignins. Although all composites studied present remarkable antioxidant features, the novel LA-lignin-PBS systems stand out in terms of antiadhesion activity against both Gram-positive and Gram-negative bacteria. Overall, the systematic analysis performed in this work regarding the impact of various lignins on the formed PBS composites enables a better understanding of the essential structural and compositional lignin features for achieving biobased materials with superior properties.
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| 29. |
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| 30. |
- Singh, Digvijay, et al.
(författare)
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High-temperature oxidation behaviour of nanostructure surface layered austenitic stainless steel
- 2022
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332. ; 581
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Tidskriftsartikel (refereegranskat)abstract
- The present study investigates the high-temperature oxidation behaviour of nanostructure surface layered AISI 304L stainless steel. A severely deformed layer of ∼300 μm thickness, consisting of nanoscale grains (∼40 nm size) in the topmost region, is successfully developed using the surface mechanical attrition treatment (SMAT) process. The SMATed layer is substantially stable up to 700 °C; however, the surface hardness is reduced by ∼37% at 800 °C for 25 h oxidation duration. Glow discharge optical emission spectroscopy and X-ray photoelectron spectroscopy analysis revealed the considerable difference in the chemistry and elemental distribution across the oxide scale of SMATed and non-SMATed specimens. Adherent, denser, and thinner scale, dominated by nanocrystals of Cr- and Mn-rich oxides, is formed on the SMATed steel. However, the Fe-oxide dominated scale containing micro-crystals is found on the non-SMATed specimens, which shows noticeable exfoliation. A high density of grain boundaries and lattice defects in the SMATed layer display admirable reactive diffusion properties of Cr and Mn during oxidation of steel, instigating the formation of a protective oxide scale. The SMATed specimens exhibit multiple zones in the oxide scale: (i) Cr/Mn depleted outer layer, (ii) Cr-/Mn-rich inner layer, and (iii) gradually decreasing Cr/Mn region.
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| 31. |
- Yu, Hao, et al.
(författare)
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Association of an estrogen-sensitive Pax1-Col11a1-Mmp3 signaling axis with adolescent idiopathic scoliosis.
- 2023
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than five-fold greater risk of severe disease compared to boys. Despite its medical impact, the molecular mechanisms that drive AIS are largely unknown. We previously defined a female-specific AIS genetic risk locus in an enhancer near the PAX1 gene. Here we sought to define the roles of PAX1 and newly-identified AIS-associated genes in the developmental mechanism of AIS. In a genetic study of 9,161 individuals with AIS and 80,731 unaffected controls, significant association was identified with a variant in COL11A1 encoding collagen (α1) XI (rs3753841; NM_080629_c.4004C>T; p.(Pro1335Leu); P=7.07e -11 , OR=1.118). Using CRISPR mutagenesis we generated Pax1 knockout mice ( Pax1 -/- ). In postnatal spines we found that Pax1 and collagen (α1) XI protein both localize within the intervertebral disc (IVD)-vertebral junction region encompassing the growth plate, with less collagen (α1) XI detected in Pax1 -/- spines compared to wildtype. By genetic targeting we found that wildtype Col11a1 expression in growth plate cells (GPCs) suppresses expression of Pax1 and of Mmp3 , encoding the matrix metalloproteinase 3 enzyme implicated in matrix remodeling. However, this suppression was abrogated in the presence of the AIS-associated COL11A1 P1335L mutant. Further, we found that either knockdown of the estrogen receptor gene Esr2 , or tamoxifen treatment, significantly altered Col11a1 and Mmp3 expression in GPCs. These studies support a new molecular model of AIS pathogenesis wherein genetic variation and estrogen signaling increase disease susceptibility by altering a Pax1 - Col11a1 - Mmp3 signaling axis in the growth plate.
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- Yu, Hao, et al.
(författare)
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Association of genetic variation in COL11A1 with adolescent idiopathic scoliosis
- 2024
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Ingår i: eLIFE. - : eLife Sciences Publications, Ltd. - 2050-084X. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than fivefold greater risk of severe disease compared to boys. Despite its medical impact, the molecular mechanisms that drive AIS are largely unknown. We previously defined a female-specific AIS genetic risk locus in an enhancer near the PAX1 gene. Here, we sought to define the roles of PAX1 and newly identified AIS-associated genes in the developmental mechanism of AIS. In a genetic study of 10,519 individuals with AIS and 93,238 unaffected controls, significant association was identified with a variant in COL11A1 encoding collagen (α1) XI (rs3753841; NM_080629.2_c.4004C>T; p.(Pro1335Leu); p=7.07E-11, OR = 1.118). Using CRISPR mutagenesis we generated Pax1 knockout mice (Pax1-/-). In postnatal spines we found that PAX1 and collagen (α1) XI protein both localize within the intervertebral disc-vertebral junction region encompassing the growth plate, with less collagen (α1) XI detected in Pax1-/- spines compared to wild-type. By genetic targeting we found that wild-type Col11a1 expression in costal chondrocytes suppresses expression of Pax1 and of Mmp3, encoding the matrix metalloproteinase 3 enzyme implicated in matrix remodeling. However, the latter suppression was abrogated in the presence of the AIS-associated COL11A1P1335L mutant. Further, we found that either knockdown of the estrogen receptor gene Esr2 or tamoxifen treatment significantly altered Col11a1 and Mmp3 expression in chondrocytes. We propose a new molecular model of AIS pathogenesis wherein genetic variation and estrogen signaling increase disease susceptibility by altering a PAX1-COL11a1-MMP3 signaling axis in spinal chondrocytes.
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