| 1. |
- Fryk, Emanuel, et al.
(författare)
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Microdialysis and proteomics of subcutaneous interstitial fluid reveals increased galectin-1 in type 2 diabetes patients
- 2016
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Ingår i: Metabolism-Clinical and Experimental. - : Elsevier BV. - 0026-0495 .- 1532-8600. ; 65:7, s. 998-1006
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Tidskriftsartikel (refereegranskat)abstract
- Objective. To identify a potential therapeutic target for type 2 diabetes by comparing the subcutaneous interstitial fluid from type 2 diabetes patients and healthy men. Methods. Proteomics was performed on the interstitial fluid of subcutaneous adipose tissue obtained by microdialysis from 7 type 2 diabetes patients and 8 healthy participants. 851 proteins were detected, of which 36 (including galectin-1) showed significantly altered expression in type 2 diabetes. We also measured galectin-1 expression in: (1) adipocytes isolated from adipose tissue biopsies from these participants; (2) subcutaneous adipose tissue of 24 obese participants before, during and after 16 weeks on a very low calorie diet (VLCD); and (3) adipocytes isolated from 6 healthy young participants after 4 weeks on a diet and lifestyle intervention to promote weight gain. We also determined the effect of galectin-1 on glucose uptake in human adipose tissue. Results. Galectin-1 protein levels were elevated in subcutaneous dialysates from type 2 diabetes compared with healthy controls (p < 0.05). In agreement, galectin-1 mRNA expression was increased in adipocytes from the type 2 diabetes patients (p < 0.05). Furthermore, galectin-1 mRNA expression was decreased in adipose tissue after VLCD (p < 0.05) and increased by overfeeding (p < 0.05). Co-incubation of isolated human adipocytes with galectin-1 reduced glucose uptake (p < 0.05) but this was independent of the insulin signal. Conclusion. Proteomics of the interstitial fluid in subcutaneous adipose tissue in vivo identified a novel adipokine, galectin-1, with a potential role in the pathophysiology of type 2 diabetes. (C) 2016 Elsevier Inc. All rights reserved.
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| 2. |
- Antoni, Per, et al.
(författare)
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Europium confined cyclen dendrimers with photophysically active triazoles
- 2008
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Ingår i: Journal of Materials Chemistry. - : Royal Society of Chemistry (RSC). - 0959-9428 .- 1364-5501. ; 18:22, s. 2545-2554
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Tidskriftsartikel (refereegranskat)abstract
- Dendrimers up to the fourth generation (G1-G4) were successfully synthesized via the efficient copper catalyzed 1,3-dipolar cycloaddition between primary alkynes and azides (CuAAC), also referred to as a click reaction. The synthetic protocol involved the preparation of presynthesized dendron wedges that subsequently were attached to a tetra-valent alkyne functional cyclen core. These constructed structures integrated stable triazole groups "intra-locked'' between the cyclen and dendron wedges. The incorporation of a lanthanide metal ion, europium, into the interior of all cyclen dendrimers was monitored by FT-IR. Interestingly, the photophysical results showed that the proximate triazole not only acts as a stable linker but also as a sensitizers, transferring its singlet-singlet excitation in the ultraviolet region (270-290 nm) to the partially filled luminescent lanthanide 4f shell. An increase of luminescence decay time from the lanthanide D-5(0) -> F-7(2) emission was observed with increasing dendrimer size, indicating that the shielding effect of the dendron wedges is important for the relaxation of the photo-excitation and energy transfer. To the best of our knowledge, this is the first time a set of dendron wedges have successfully been attached to a cyclen metal ion cage via the versatile click reaction. Furthermore, the produced triazoles intra-locked in close proximity to the macrocycle core elucidated an interesting photophysical function.
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| 3. |
- Berglund, Olof, et al.
(författare)
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Persistent organic pollutants in river food webs: influence of trophic position and degree of heterotrophy
- 2005
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Ingår i: Canadian Journal of Fisheries and Aquatic Sciences. - 1205-7533. ; 62:9, s. 2021-2032
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated how the degree of autotrophy/heterotrophy and organism trophic position influenced the bioaccumulation of polychlorinated biphenyls (PCBs) in 10 benthic river food webs consisting of terrestrial detritus, periphyton, invertebrates, and age-0 brown trout (Salmo trutta) in southern Sweden. Concentrations of PCBs increased with trophic position, estimated from delta(15)N and delta(13)C, on a dry weight basis (ng center dot g(-1) dry weight) but not on a lipid weight basis (ng center dot g(-1) lipid). PCB biomagnification factors between the first and second trophic levels (invertebrates/ periphyton and invertebrates/detritus) ranged between 0.3 and 2.3 and between the second and third levels (trout/invertebrates) between 0.3 and 2.0 on a lipid weight basis. The mean proportion of carbon ultimately derived from terrestrial sources, alpha, was 0.82 +/- 0.19 for invertebrates and 0.67 +/- 0.28 for trout. Contrary to our hypothesis, PCB concentrations in trout were positively related to alpha (r(2) = 0.58-0.77, p < 0.05). As alpha and the periphyton density (g C center dot m(-2)) in the rivers was positively related (r(2) = 0.88, p < 0.01), we propose that this relationship was due to an increased retention and exposure of PCBs to trout in rivers with low grazing pressure and high periphyton density.
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| 4. |
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| 5. |
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| 6. |
- Hansson, Lars-Anders, et al.
(författare)
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Consumption patterns, complexity and enrichment in aquatic food chains
- 1998
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Ingår i: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954. ; 265:1399, s. 901-906
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Tidskriftsartikel (refereegranskat)abstract
- The interactions between consumers and prey, and their impact on biomass distribution among trophic levels, are central issues in both empirical and theoretical ecology. In a long-term experiment, where all organisms, including the top predator, were allowed to respond to environmental conditions by reproduction, we tested predictions from `prey-dependent' and `ratio-dependent' models. Prey-dependent models made correct predictions only in the presence of strong interactors in simple food chains, but failed to predict patterns in more complex situations. Processes such as omnivory, consumer excretion, and unsuitable prey-size windows (invulnerable prey) increased the complexity and created patterns resembling ratio-dependent consumption. However, whereas the prey-dependent patterns were created by the mechanisms predicted by the model, ratio-dependent patterns were not, suggesting that they may be right for the wrong reason'. We show here that despite the enormous complexity of ecosystems, it is possible to identify and disentangle mechanisms responsible for observed patterns in community structure, as well as in biomass development of organisms ranging in size from bacteria to fish.
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| 7. |
- Holmqvist, Niklas, et al.
(författare)
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Lake trophic status and bioaccumulation of polychlorinated biphenyls in benthic organisms: a comparison between littoral and profundal invertebrates
- 2005
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Ingår i: Canadian Journal of Fisheries and Aquatic Sciences. - 1205-7533. ; 62:6, s. 1201-1209
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the influence of lake trophic status on accumulation of polychlorinated biphenyls (PCBs) in littoral and profundal invertebrates from 19 lakes in southern Sweden. The PCB concentration in profundal chironomids (Chironomus sp.) was negatively correlated with lake trophy but the concentration in littoral crayfish (Pacifasticus leniusculus) was unrelated to shifting nutrient regimes. PCB concentrations in chironomids were negatively correlated, while crayfish did not correlate with lake total phosphorus. Two findings indicate that different processes determine bioaccumulation in littoral and profundal invertebrates: (i) a lack of correlation between PCB concentrations in crayfish and chironomids within lakes and (ii) some differences in congener distribution in the two species. We suggest a possible explanation in that chironomids are directly exposed to settling material from the pelagic zone, while crayfish are omnivorous and feed mainly in the littoral zone. A intensive investigation on one pond population could not reveal any individual factors, such as lipid content, size, or sex, influencing bioaccumulation of PCBs in crayfish.
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| 8. |
- Holmqvist, Niklas, et al.
(författare)
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Low levels of persistent organic pollutants (POPS) in New Zealand eels reflect isolation from atmospheric sources
- 2006
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491. ; 141:3, s. 532-538
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Tidskriftsartikel (refereegranskat)abstract
- Polychlorinated biphenyls (PCBs) and organic pesticides (i.e., DDTs) were measured in long finned eels (Anguilla dieffenbachii) in 17 streams on the west coast of South Island, New Zealand. Very low levels of PCBs and low levels of ppDDE were found. The concentrations of PCBs and ppDDE were not correlated within sites indicating that different processes determined the levels of the two pollutants in New Zealand eels. The PCBs probably originate from atmospheric transport, ppDDE levels are determined by land use and are higher in agriculture areas. The low contamination level of these aquatic systems seems to be a function of a low input from both long and short-range transport as well as few local point sources. No correlation could be found between lipid content and persistent organic pollutants (POPs) concentration (as shown in previous studies) in the eels which could be explained by low and irregular intake of the pollutants.
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| 9. |
- Holmqvist, Niklas, et al.
(författare)
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Persistent organic pollutants (POP) in a benthic omnivore - A comparison between lake and stream crayfish populations
- 2007
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Ingår i: Chemosphere. - : Elsevier BV. - 1879-1298 .- 0045-6535. ; 66:6, s. 1070-1078
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the accumulation of PCB and DDT in crayfish populations in 10 streams in southern Sweden. The results were compared with an earlier study on crayfish in lakes from the same area. We found that the concentration of pollutants in crayfish did not differ between the two types of systems. Variation in body burden was higher in stream living crayfish probably because of the higher influence from pollutants deposited in the catchment area and the more dynamic transport in streams. In streams, pp'-DDE concentrations were positively correlated to trophic status (total phosphorous) while PCB did not show any correlation with the nutrient regime. Further, mean Sigma PCB and p,p'-DDE concentrations in crayfish did not correlate in streams. We suggest that the sources of the two pollutants differ for stream living crayfish. The results indicate that crayfish in streams are affected to a higher degree to pollutants in the catchment area and the precipitation regime. In lakes, internal processes govern uptake of pollutants in crayfish.
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| 10. |
- Jephson, Therese, et al.
(författare)
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Trophic interactions in Zostera marina beds along the Swedish coast
- 2008
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Ingår i: Marine Ecology - Progress Series. - : Inter-Research Science Center. - 1616-1599 .- 0171-8630. ; 369, s. 63-76
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Tidskriftsartikel (refereegranskat)abstract
- We compared eelgrass Zostera marina communities in 3 regions in Sweden believed to be affected by eutrophication and overfishing, to determine whether bottom-up or top-down processes control the biomass of epiphytic macroalgae and grazers. Nitrogen and carbon isotope signatures were analyzed to explore the food webs and to identify the grazing species feeding on filamentous algae and/or eelgrass. Mixing model (IsoSource version 1.3.1) analysis of the isotope signatures indicated that the amphipods Gammarus locusta and Microdeutopus gryllotalpa fed primarily on filamentous algae and that only 2 small gastropod species consumed eelgrass. Moreover, the grass shrimp Palaemon elegans and F adspersus were ca. 1 trophic level above amphipods and algae, but according to the mixing model played different trophic roles in the different areas. The highest biomass of filamentous algae was found in the west coast beds housing grazers with the lowest biomass and mean size (predominantly G. locusta and M. gryllotalpa, 0.5 to 3 mm). In contrast, the Baltic Sea beds had low algal biomass, but the grazers (mostly G. locusta and Idotea baltica) had higher biomass and were significantly larger (mean size ca. 10 mm). An overall negative correlation was found between grazer biomass and biomass of filamentous algae. The significantly smaller grazers and absence of isopod grazers on the west coast may be due to substantial consumption by small predatory fish. This supports the suggestions that, in Swedish eelgrass beds, grazers are top-down controlled, and overexploitation. of large predators and eutrophication play an important role in the recent increases in algal biomass.
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| 11. |
- Kotta, Jonne, et al.
(författare)
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Cleaning up seas using blue growth initiatives: Mussel farming for eutrophication control in the Baltic Sea
- 2020
-
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 709
-
Tidskriftsartikel (refereegranskat)abstract
- © 2019 The Authors Eutrophication is a serious threat to aquatic ecosystems globally with pronounced negative effects in the Baltic and other semi-enclosed estuaries and regional seas, where algal growth associated with excess nutrients causes widespread oxygen free “dead zones” and other threats to sustainability. Decades of policy initiatives to reduce external (land-based and atmospheric) nutrient loads have so far failed to control Baltic Sea eutrophication, which is compounded by significant internal release of legacy phosphorus (P) and biological nitrogen (N) fixation. Farming and harvesting of the native mussel species (Mytilus edulis/trossulus) is a promising internal measure for eutrophication control in the brackish Baltic Sea. Mussels from the more saline outer Baltic had higher N and P content than those from either the inner or central Baltic. Despite their relatively low nutrient content, harvesting farmed mussels from the central Baltic can be a cost-effective complement to land-based measures needed to reach eutrophication status targets and is an important contributor to circularity. Cost effectiveness of nutrient removal is more dependent on farm type than mussel nutrient content, suggesting the need for additional development of farm technology. Furthermore, current regulations are not sufficiently conducive to implementation of internal measures, and may constitute a bottleneck for reaching eutrophication status targets in the Baltic Sea and elsewhere.
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| 12. |
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| 13. |
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| 14. |
- Larsson, Per, et al.
(författare)
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Heavy metals and stable isotopes in a benthic omnivore in a trophic gradient of lakes
- 2007
-
Ingår i: Environmental Science & Technology. - : American Chemical Society (ACS). - 1520-5851 .- 0013-936X. ; 41:17, s. 5973-5979
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Tidskriftsartikel (refereegranskat)abstract
- Heavy metals (Cd, Hg, and Pb) and stable isotopes (N-15, C-13) in crayfish (Pacifastacus leniusculus) were studied in a trophic gradient of lakes (N = 19) in southern Sweden. Trophic indicators of the lakes as total phosphorus (tot-P) varied from 5 to 93 mu g/L. The examined lakes had no known point sources of heavy metals, but the catchment areas varied from mainly forested to agricultural land. Cd and Hg in crayfish were affected by the trophic status of the lakes, showing significant negative relationship with tot-P, total nitrogen, and chlorophyll A content and a positive relationship with lake transparency (Secchi depth). The concentration of these two heavy metals was thus higher in crayfish in the oligotrophic lakes and decreased linearly to the eutrophic ones. Pb was not related to any lake variable. Stable isotopes of carbon (delta C-13) and nitrogen (615N) in crayfish were a reflection of that found in the sediment as shown by positive linear relationships for the lakes. In the sediment of the lakes, delta C-13 signature showed significant negative relationships with the trophic indicators but positive results were shown for lake transparency. The trophic gradient of the lakes was reflected by delta C-13 in the sediment and in the crayfish. 615N in crayfish was a reflection of 615N in the sediment but the relationship was not coupled to the trophic statue of the lakes. The results from the study show that Cd and Hg in benthic omnivores as crayfish are affected by ecological processes in lakes, such as eutrophication. Stable isotopes, such as 13C and 15 N, can be used to study these ecological processes.
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| 15. |
- Lindblom, Per, 1974, et al.
(författare)
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Endothelial PDGF-B retention is required for proper investment of pericytes in the microvessel wall.
- 2003
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Ingår i: Genes & development. - : Cold Spring Harbor Laboratory. - 0890-9369 .- 1549-5477. ; 17:15, s. 1835-40
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Tidskriftsartikel (refereegranskat)abstract
- Several platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) family members display C-terminal protein motifs that confer retention of the secreted factors within the pericellular space. To address the role of PDGF-B retention in vivo, we deleted the retention motif by gene targeting in mice. This resulted in defective investment of pericytes in the microvessel wall and delayed formation of the renal glomerulus mesangium. Long-term effects of lack of PDGF-B retention included severe retinal deterioration, glomerulosclerosis, and proteinuria. We conclude that retention of PDGF-B in microvessels is essential for proper recruitment and organization of pericytes and for renal and retinal function in adult mice.
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| 16. |
- Nyström, Andreas, et al.
(författare)
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Characterization of Poly(norbornene) Dendronized Polymers Prepared by Ring-Opening Metathesis Polymerization of Dendron Bearing Monomers
- 2006
-
Ingår i: Macromolecules. - : American Chemical Society (ACS). - 0024-9297 .- 1520-5835. ; 39:21, s. 7241-7249
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Tidskriftsartikel (refereegranskat)abstract
- The preparation and characterization of a series of first to fourth generation dendronized poly-(norbornene)s are presented. The monomers were synthesized in a divergent fashion from 5-norbornene-2-methanol, utilizing the acetonide protected anhydride of 2,2-bis(methylol)propionic acid. The norbornenyl bearing dendrons were polymerized by ring-opening metathesis polymerization, and it was found that the Grubbs' first generation catalyst resulted in polymers with lower polydispersity compared to the materials obtained when employing the second generation catalyst. Two series of first to fourth generation polymers were characterized by DSC, SEC, and dynamic rheological measurements. In addition, it was found that the fourth generation material could form regular, porous membranes and birefringent fibers. The membranes were characterized with atomic force and optical microscopy. The birefringent fibers were analyzed with X-ray diffraction, polarized FTIR, and polarized optical microscopy.
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| 17. |
- Nyström, Per, et al.
(författare)
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Crayfish in lakes and streams: individual and population responses to predation, productivity and substratum availability
- 2006
-
Ingår i: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 51:11, s. 2096-2113
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Tidskriftsartikel (refereegranskat)abstract
- 1. In a correlative study, we investigated the relative importance of fish predation, refuge availability and resource supply in determining the abundance and size distributions of the introduced and omnivorous signal crayfish (Pacifastacus leniusculus) in lakes and streams. Moreover, the biomass and food selection of predatory fish was estimated in each habitat type and stable isotopes of carbon and nitrogen were measured in perch (Perca fluviatilis), the dominant predator in the lakes, and in its potential food sources (crayfish, juvenile roach and isopods). 2. In lakes, crayfish were the most frequent prey in large perch (46%), followed by other macroinvertebrates (26%, including the isopod Asellus aquaticus) and small fish (25%). Crayfish and fish dominated the gut contents of large perch with respect to biomass. Nitrogen signatures showed that perch were one trophic level above crayfish (approx. 3.4 parts per thousand) and a two-source mixing model using nitrogen isotope values indicated that crayfish (81%) contributed significantly more to perch isotope values than did juvenile roach (19%). A positive correlation was found between the abundance of crayfish and the biomass of large perch. Crayfish abundance in lakes was also positively correlated with the proportion of cobbles in the littoral zone. Lake productivity (chlorophyll a) was positively correlated with crayfish size, but not with crayfish abundance. 3. In streams, brown trout (Salmo trutta) were the most abundant predatory fish. Gut contents of large trout in a forested stream showed that terrestrial insects were the most frequently found prey (60%), followed by small crayfish (27%) and isopods (27%). In contrast to lakes, the relative abundance of crayfish was negatively correlated with the total biomass of predatory fish and with total biomass of trout. However, abundance of crayfish at sites with a low biomass of predatory fish varied considerably and was related to substratum grain size, with fewer crayfish being caught when the substratum was sandy or dominated by large boulders. The mean size of crayfish was greater at stream sites with a high standing stock of periphyton, but neither predator biomass nor substratum grain size was correlated with crayfish size. 4. Our results suggest that bottom-up processes influence crayfish size in lakes and streams independent of predator biomass and substratum availability. However, bottom-up processes do not influence crayfish abundance. Instead, substratum availability (lakes) and interactions between predation and substratum grain size (streams) need to be considered in order to predict crayfish abundance.
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| 18. |
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| 19. |
- Nyström Sandman, Antonia, et al.
(författare)
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Grön infrastruktur i havet : landskapsperspektiv i förvaltningen av Sveriges marina områden
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- En kartläggning av havets naturkvaliteter har påbörjats genom arbetet med grön infrastruktur. Rapporten undersöker olika scenarier för hur den marina gröna infrastrukturen påverkas av mänskliga aktiviteter i förhållande till olika strategier för förvaltning. Projektet har genomfört tre fallstudier med olika fokus: strandexploatering, trålfiske och klimatförändring. Genom scenariobaserade analyser visar forskarna vilken effekt olika beslut och åtgärder kan få på naturskydds- och miljömål.Det tvärvetenskapliga projektet är ett samarbete mellan experter inom ekologi och juridik. Forskarna beskriver hur lagstiftning, planering och förvaltningsstrategier bör utformas och fungera ihop, och presenterar förslag för att stärka skyddet av den gröna infrastrukturen i Sveriges havsområden.Forskningen har finansierats av Naturvårdsverkets miljöforskningsanslag till stöd för Naturvårdsverket och Havs- och vattenmyndighetens verksamhet.
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| 20. |
- Parvin, Farjana, et al.
(författare)
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Divergent Age-Dependent Conformational Rearrangement within Aβ Amyloid Deposits in APP23, APPPS1, and AppNL-F Mice
- 2024
-
Ingår i: ACS Chemical Neuroscience. - : AMER CHEMICAL SOC. - 1948-7193. ; 15:10, s. 2058-2069
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Tidskriftsartikel (refereegranskat)abstract
- Amyloid plaques composed of fibrils of misfolded A beta peptides are pathological hallmarks of Alzheimer's disease (AD). A beta fibrils are polymorphic in their tertiary and quaternary molecular structures. This structural polymorphism may carry different pathologic potencies and can putatively contribute to clinical phenotypes of AD. Therefore, mapping of structural polymorphism of A beta fibrils and structural evolution over time is valuable to understanding disease mechanisms. Here, we investigated how A beta fibril structures in situ differ in A beta plaque of different mouse models expressing familial mutations in the A beta PP gene. We imaged frozen brains with a combination of conformation-sensitive luminescent conjugated oligothiophene (LCO) ligands and A beta-specific antibodies. LCO fluorescence mapping revealed that mouse models APP23, APPPS1, and App(NL-F) have different fibril structures within A beta-amyloid plaques depending on the A beta PP-processing genotype. Co-staining with A beta-specific antibodies showed that individual plaques from APP23 mice expressing A beta PP Swedish mutation have two distinct fibril polymorph regions of core and corona. The plaque core is predominantly composed of compact A beta 40 fibrils, and the corona region is dominated by diffusely packed A beta 40 fibrils. Conversely, the A beta PP knock-in mouse App(NL-F), expressing the A beta PP Iberian mutation along with Swedish mutation has tiny, cored plaques consisting mainly of compact A beta 42 fibrils, vastly different from APP23 even at elevated age up to 21 months. Age-dependent polymorph rearrangement of plaque cores observed for APP23 and APPPS1 mice >12 months, appears strongly promoted by A beta 40 and was hence minuscule in App(NL-F). These structural studies of amyloid plaques in situ can map disease-relevant fibril polymorph distributions to guide the design of diagnostic and therapeutic molecules.
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| 21. |
- Persson, Anders, et al.
(författare)
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Effects of enrichment on simple aquatic food webs
- 2001
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Ingår i: American Naturalist. - : University of Chicago Press. - 0003-0147 .- 1537-5323. ; 157:6, s. 654-669
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Tidskriftsartikel (refereegranskat)abstract
- Simple models, based on Lotka-Volterra types of interactions between predator and prey, predict that enrichment will have a destabilizing effect on populations and that equilibrium population densities will change at the top trophic level and every second level below. We experimentally tested these predictions in three aquatic food web configurations subjected to either high or low nutrient additions. The results were structured by viewing the systems as either food chains or webs and showed that trophic level biomass increased with enrichment, which contradicts food chain theory. However, within each trophic level, food web configuration affected the extent to which different functional groups responded to enrichment. By dividing trophic levels into functional groups, based on vulnerability to consumption, we were able to identify significant effects that were obscured when systems were viewed as food chains. The results support the prediction that invulnerable prey may stabilize trophic-level dynamics by replacing other, more vulnerable prey. Furthermore, the vulnerable prey, such as Daphnia and edible algae, responded as predicted by the paradox of enrichment hypothesis; that is, variability in population density increased with enrichment. Hence, by describing ecosystems as a matrix of food web interactions, and by recognizing the interplay between interspecific competition and predation, a more complete description of the ecosystem function was obtained compared to when species were placed into distinct trophic levels.
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| 22. |
- Persson, Anders, et al.
(författare)
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Effects of enrichment on simple aquatic food webs
- 2001
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Ingår i: The American Naturalist. ; 157:6, s. 654-669
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Tidskriftsartikel (refereegranskat)abstract
- Simple models, based on Lotka-Volterra types of interactions between predator and prey, predict that enrichment will have a destabilizing effect on
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| 23. |
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| 24. |
- Shovsky, Alexander, et al.
(författare)
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Cationic poly(N -isopropylacrylamide) block copolymer adsorption investigated by dual polarization interferometry and lattice mean-field theory
- 2012
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Ingår i: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 28:39, s. 14028-14038
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Tidskriftsartikel (refereegranskat)abstract
- A series of cationic diblock copolymers, poly(N-isopropylacrylamide) 48-block-poly((3-acrylamidopropyl)trimethylammonium chloride) X, abbreviated as PNIPAAM48-b-PAMPTMA+ X (X = 0, 6, 10, 14, and 20), has been synthesized, and their adsorption onto silicon oxynitride from aqueous solution has been investigated using dual polarization interferometry. The polymer adsorption was modeled by using a lattice mean-field theory, and a satisfactory consistency between theory and experiments was found in terms of surface excess and layer thickness. Both theory and experiments show that the adsorption is limited by steric repulsion for X < Xmax and by electrostatic interactions for X > X max. Modeling demonstrates that significant surface charge regulation occurs due to adsorption. Both the nonionic and cationic block exhibit nonelectrostatic affinity to silicon oxynitride and thus contribute to the driving force for adsorption, and modeling is used for clarifying how changes in the nonelectrostatic affinity affects the surface excess. The segments of the nonionic and cationic blocks seem less segregated when both have a nonelectrostatic affinity for the surface compared to the case where the segments had no surface affinity. Adsorption kinetics was investigated experimentally. Two kinetic regimes were observed: the adsorption rate is initially controlled by the mass transfer rate to the surface and at higher coverage is limited by the attachment rate.
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| 25. |
- Stenroth, Patrik, et al.
(författare)
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Stable isotopes as an indicator of diet in omnivorous crayfish (Pacifastacus leniusculus): the influence of tissue, sample treatment, and season
- 2006
-
Ingår i: Canadian Journal of Fisheries and Aquatic Sciences. - 1205-7533. ; 63:4, s. 821-831
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Tidskriftsartikel (refereegranskat)abstract
- Stable isotopes have been used to analyse food webs and (or) trace movements of animals for about 30 years. There has been some debate on the use of different tissues and treatments before isotope analysis, as well as on seasonal effects. We found different crayfish (Pacifastacus leniusculus) tissues (muscle, hepatopancreas, exoskeleton, gill, and whole body) to have different isotope values. Lipid extraction made whole-body carbon isotope values higher but had no effect on nitrogen isotope values. Acidification made whole-body isotope values lower. For crayfish, there was no seasonal or interannual variation in isotope values. In contrast to studies based on gut content analysis, we found adult crayfish to be at least as carnivorous as young-of-the-year crayfish. Earlier studies often have assumed that each food source contributes both nitrogen and carbon in equal proportions. Omnivores do not fit easily into this view. We suggest that nitrogen and carbon in an organism could come from different sources. Adopting this view for a pond food web could render crayfish both predators and detritivores as crayfish prey on nitrogen sources (other invertebrates) and consume large amounts of detritus to satisfy their carbon demand.
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| 26. |
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| 27. |
- Stenroth, Patrik, et al.
(författare)
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The influence of productivity and width of littoral zone on the trophic position of a large-bodied omnivore.
- 2008
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Ingår i: Oecologia. - : Springer Science and Business Media LLC. - 1432-1939 .- 0029-8549. ; 156, s. 681-690
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Tidskriftsartikel (refereegranskat)abstract
- Omnivory is common in many food webs. Omnivores in different habitats can potentially change their feeding behaviour and alter their trophic position and role according to habitat conditions. Here we examine the trophic level and diet of the omnivorous signal crayfish (Pacifastacus leniusculus) in gradients of trophic status and lake size, both of which have been previously suggested to affect trophic position of predators separately or combined as productive space. We found the trophic position of omnivorous crayfish to be positively correlated with lake trophic status, but found no evidence for any influence of lake size or productive space on crayfish trophic position. The higher trophic position of crayfish in eutrophic lakes was largely caused by a shift in crayfish diet and not by an increase in trophic links in basal parts of the food web. Hence, our results support the "productivity hypothesis," suggesting that food chains can be longer in more productive systems. Furthermore, stable isotope data indicated that larger crayfish are more predatory than smaller crayfish in lakes with wider littoral zones. Wider littoral zones promoted the development of intrapopulation differences in trophic position whereas narrow littoral zones did not. Hence, differences in habitat quality between and within lakes seem to influence the trophic positions of omnivorous crayfish.
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| 28. |
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| 29. |
- Tesi, Bianca, et al.
(författare)
-
Diagnostic yield and clinical impact of germline sequencing in children with CNS and extracranial solid tumors : a nationwide, prospective Swedish study
- 2024
-
Ingår i: The Lancet Regional Health. - : Elsevier. - 2666-7762. ; 39
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundChildhood cancer predisposition (ChiCaP) syndromes are increasingly recognized as contributing factors to childhood cancer development. Yet, due to variable availability of germline testing, many children with ChiCaP might go undetected today. We report results from the nationwide and prospective ChiCaP study that investigated diagnostic yield and clinical impact of integrating germline whole-genome sequencing (gWGS) with tumor sequencing and systematic phenotyping in children with solid tumors.MethodsgWGS was performed in 309 children at diagnosis of CNS (n = 123, 40%) or extracranial (n = 186, 60%) solid tumors and analyzed for disease-causing variants in 189 known cancer predisposing genes. Tumor sequencing data were available for 74% (227/309) of patients. In addition, a standardized clinical assessment for underlying predisposition was performed in 95% (293/309) of patients.FindingsThe prevalence of ChiCaP diagnoses was 11% (35/309), of which 69% (24/35) were unknown at inclusion (diagnostic yield 8%, 24/298). A second-hit and/or relevant mutational signature was observed in 19/21 (90%) tumors with informative data. ChiCaP diagnoses were more prevalent among patients with retinoblastomas (50%, 6/12) and high-grade astrocytomas (37%, 6/16), and in those with non-cancer related features (23%, 20/88), and ≥2 positive ChiCaP criteria (28%, 22/79). ChiCaP diagnoses were autosomal dominant in 80% (28/35) of patients, yet confirmed de novo in 64% (18/28). The 35 ChiCaP findings resulted in tailored surveillance (86%, 30/35) and treatment recommendations (31%, 11/35).InterpretationOverall, our results demonstrate that systematic phenotyping, combined with genomics-based diagnostics of ChiCaP in children with solid tumors is feasible in large-scale clinical practice and critically guides personalized care in a sizable proportion of patients.
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| 30. |
- Tesi, Bianca, et al.
(författare)
-
Diagnostic yield and clinical impact of germline sequencing in children with CNS and extracranial solid tumors : a nationwide, prospective Swedish study
- 2024
-
Ingår i: The Lancet Regional Health. - : Elsevier. - 2666-7762. ; 39
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Childhood cancer predisposition (ChiCaP) syndromes are increasingly recognized as contributing factors to childhood cancer development. Yet, due to variable availability of germline testing, many children with ChiCaP might go undetected today. We report results from the nationwide and prospective ChiCaP study that investigated diagnostic yield and clinical impact of integrating germline whole-genome sequencing (gWGS) with tumor sequencing and systematic phenotyping in children with solid tumors.Methods: gWGS was performed in 309 children at diagnosis of CNS (n = 123, 40%) or extracranial (n = 186, 60%) solid tumors and analyzed for disease-causing variants in 189 known cancer predisposing genes. Tumor sequencing data were available for 74% (227/309) of patients. In addition, a standardized clinical assessment for underlying predisposition was performed in 95% (293/309) of patients.Findings: The prevalence of ChiCaP diagnoses was 11% (35/309), of which 69% (24/35) were unknown at inclusion (diagnostic yield 8%, 24/298). A second-hit and/or relevant mutational signature was observed in 19/21 (90%) tumors with informative data. ChiCaP diagnoses were more prevalent among patients with retinoblastomas (50%, 6/12) and high-grade astrocytomas (37%, 6/16), and in those with non-cancer related features (23%, 20/88), and ≥2 positive ChiCaP criteria (28%, 22/79). ChiCaP diagnoses were autosomal dominant in 80% (28/35) of patients, yet confirmed de novo in 64% (18/28). The 35 ChiCaP findings resulted in tailored surveillance (86%, 30/35) and treatment recommendations (31%, 11/35).Interpretation: Overall, our results demonstrate that systematic phenotyping, combined with genomics-based diagnostics of ChiCaP in children with solid tumors is feasible in large-scale clinical practice and critically guides personalized care in a sizable proportion of patients.Funding: The study was supported by the Swedish Childhood Cancer Fund and the Ministry of Health and Social Affairs.
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| 31. |
- Wennstig, Anna-Karin, et al.
(författare)
-
Inter-observer variation in delineating the coronary arteries as organs at risk
- 2017
-
Ingår i: Radiotherapy and Oncology. - : ELSEVIER IRELAND LTD. - 0167-8140 .- 1879-0887. ; 122:1, s. 72-78
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: To determine the inter-observer variation in delineating the coronary arteries as organs at risk (OAR) in breast cancer (BC) radiotherapy (RT) and how this variation affects the estimated coronary artery radiation dose.Method: Delineation of the left main and the left anterior descending coronary artery (LMCA and LAD), and the right coronary artery (RCA), by using the heart atlas by Feng et al., was performed by three radiation oncologists in 32 women who had received adjuvant RT for BC. Centres of the arteries were calculated and distances between artery centres were measured and the artery radiation doses were estimated. The intraclass correlation coefficient (ICC) was used to quantify the variability in doses.Results: Along the extent of RCA, the median distance between centres of arteries varied from 2 to 9 mm with similar patterns over pairs of oncologists. For the LMCA-LAD the median distance varied from 1 to 4 mm. The estimated maximum radiation doses showed an ICC variation from 0.82 to 0.97.Conclusion: The coronary arteries can be reliably identified and delineated as OARs in BC RT. The spatial variance is limited and the total variation in radiation dose is almost completely determined by the between patient variation.
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| 32. |
- Agebratt, Christian, et al.
(författare)
-
A Randomized Study of the Effects of Additional Fruit and Nuts Consumption on Hepatic Fat Content, Cardiovascular Risk Factors and Basal Metabolic Rate
- 2016
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:1, s. e0147149-
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundFruit has since long been advocated as a healthy source of many nutrients, however, the high content of sugars in fruit might be a concern.ObjectivesTo study effects of an increased fruit intake compared with similar amount of extra calories from nuts in humans.MethodsThirty healthy non-obese participants were randomized to either supplement the diet with fruits or nuts, each at +7 kcal/kg bodyweight/day for two months. Major endpoints were change of hepatic fat content (HFC, by magnetic resonance imaging, MRI), basal metabolic rate (BMR, with indirect calorimetry) and cardiovascular risk markers.ResultsWeight gain was numerically similar in both groups although only statistically significant in the group randomized to nuts (fruit: from 22.15±1.61 kg/m2 to 22.30±1.7 kg/m2, p = 0.24 nuts: from 22.54±2.26 kg/m2 to 22.73±2.28 kg/m2, p = 0.045). On the other hand BMR increased in the nut group only (p = 0.028). Only the nut group reported a net increase of calories (from 2519±721 kcal/day to 2763±595 kcal/day, p = 0.035) according to 3-day food registrations. Despite an almost three-fold reported increased fructose-intake in the fruit group (from 9.1±6.0 gram/day to 25.6±9.6 gram/day, p<0.0001, nuts: from 12.4±5.7 gram/day to 6.5±5.3 gram/day, p = 0.007) there was no change of HFC. The numerical increase in fasting insulin was statistical significant only in the fruit group (from 7.73±3.1 pmol/l to 8.81±2.9 pmol/l, p = 0.018, nuts: from 7.29±2.9 pmol/l to 8.62±3.0 pmol/l, p = 0.14). Levels of vitamin C increased in both groups while α-tocopherol/cholesterol-ratio increased only in the fruit group.ConclusionsAlthough BMR increased in the nut-group only this was not linked with differences in weight gain between groups which potentially could be explained by the lack of reported net caloric increase in the fruit group. In healthy non-obese individuals an increased fruit intake seems safe from cardiovascular risk perspective, including measurement of HFC by MRI.
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| 33. |
- Ahlgren, Johan, et al.
(författare)
-
Klimatrelaterade förändringar i sjöar och vattendrag : En jämförelse mellan två perioder (1995-2000 och 2009-2014)
- 2016
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Miljöövervakningsprogrammen ger oss möjligheten att övervaka hur storskaliga förändringar,såsom klimatet och försurningen, påverkar våra sjöar och vattendrag. Det nationellasötvattensprogrammets delprogram "Trendstationer sjöar" och "Trendstationer vattendrag"kan tillsammans med regionala övervakningsprogram ge en övergripande bild av dennuvarande statusen samt fungera som ett verktyg för övervakning av potentiella förändringari våra sötvattenssystem.En faktor som kan framkalla stora förändringar är den pågående klimatförändringen, vilkenbland annat innebär en högre medeltemperatur och förändrade vädersystem. Till exempelleder dessa förändringar till en förlängd växtsäsong och en snabbare nedbrytning av organisktmaterial i marken. Samtidigt kommer de kraftigare regnen att öka på vissa platser, vilketleder till att mer organiskt material sköljs ut i våra sjöar och vattendrag. Den ökade temperaturenförändrar också spelreglerna för de organismer som är anpassade för kallt vattenoch det möjliggör att nya områden kan koloniseras av arter som är anpassade för varmareklimat.Det finns även andra antroprogena störningar som påverkar våra sjöar och vattendrag, tillexempel utsläppen av svaveldioxid som låg bakom den kraftiga försurning av mark och vattensom man än idag ser konsekvenserna av. Utsläppen av svaveldioxid har sedan 80-taletminskat kraftigt och nu börjar man se en långsam återhämtning i vissa sjöar och vattendrag. För att förstå mer om hur dessa direkta och indirekta effekter av klimatförändringarna ochförsurningen påverkar våra svenska vatten har denna studie utvärderat tidsseriedata för perioderna1995-2000 och 2009-2014 från svenska sjöar och vattendrag. Samtliga sjöar och vattendrag i denna studie ingår i den nationella eller regionala miljöövervakningenoch totalt har 177 sjöar och 121 vattendragslokaler inkluderats i analyserna. Generellaförändringar mellan perioderna i vattenkemi och biologiska parametrar har studerats. Likaså om dessa förändringar skiljer sig åt beroende på sjöarnas och vattendragensstorlek, vattenfärg och alkalinitet. Slutligen har även sjöarnas och vattendragens geografiskaplacering baserat på de så kallade ekoregionerna inkluderats i utvärderingen.De kemisk-fysikaliska parametrar från sjöarna och vattendragen som har undersökts är lufttemperatur,absorbans, TOC (totalt organiskt kol), järn, sulfat, totalkväve, totalfosfor samtpH och alkalinitet. Förändringar avseende växtplankton har studerats med hjälp av parametrarnatotal biovolym (mm3/l), trofiskt planktonindex (TPI), antalet växtplanktonarteroch andelen cyanobakterier. För bottenfauna har förändringar av kvotenOligochaeta/Chironomidae analyserats.Resultaten visar att siktdjupet i de undersökta sjöarna minskar mellan perioderna. Dennaminskning i siktdjup kan kopplas till den ökning av TOC, absorbans och järn som sker parallellt.För vattendragen sker en liknande utveckling med en generell ökning i absorbans,TOC och järn. Dessa förändringar har dels en direkt koppling till klimatförändringarna genomen förlängd växtsäsong och dels en koppling till ökad nedbrytning vilket leder till mertillgängligt organiskt material. Vidare så kan förändringar i nederbörden påverka hur mycket av detta organiska material som spolas ut i vattensystemen. Dessutom så spelar denminskade sulfatdepositionen en stor roll i den ökande vattenfärgen och i förlängningensiktdjupet genom kemiska förändringar i jordlagren som leder till att mer material blir tillgängligtoch kan sköljas ut i vattnet. Den minskade mängden sulfat i sjöarna och vattendragenär den tydligaste förändringen i datamaterialet och kan direkt kopplas till en minskadsulfatdeposition, men inte till klimatförändringarna. Denna minskning syns även i pH ochalkaliniteten som båda generellt ökar mellan perioderna. Förändringen för pH och alkalinitetär dock inte lika tydlig som för sulfat. Även om trenderna är desamma i vattendragensom för sjöarna är förändringen dock inte lika tydlig i vattendragen. Orsaken är de fysiskaskillnaderna mellan vattendrag och sjöar, där vattendragen ser mycket kraftigare variationeri flöde inom och mellan år och därmed också i de undersökta variablerna.För sjöarnas närsalter sker också signifikanta förändringar mellan perioderna, kväve minskargenerellt, medan fosfor minskar eller ökar beroende på vilken sjötyp man tittar på. Förvattendragen sker inte några generella förändringar i fosfor mellan de undersökta perioderna,däremot så minskar kväve generellt även i vattendragen. Kväveminskningen kandelvis härledas direkt till den minskning i atmosfärisk deposition som skett under perioden,men åtgärder inom skogs- och jordbruket för att minska kväve- och fosforläckaget påverkarantagligen också förändringen av närsaltskoncentrationerna. Här kan en mer lokal utvärderingdär man även inkluderar olika kväveminskande åtgärder samt markanvändning ianalyserna, ge en bättre förståelse för vad som drivit förändringen i näringssalter.Bland de biologiska variabler som har kunnat undersökas så ökar antalet växtplanktonartergenerellt i sjöarna mellan perioderna, vilket kan vara en respons på den minskade försurningen.Vidare så ökar det trofiska planktonindexet mellan perioderna, vilket indikerar attsjöarna blivit näringsrikare. En möjlig förklaring kan också vara den ökade mängden TOCoch därmed en tillförsel av mer organiskt bundna närsalter. Det är dock så att även om detsker en ökning i trofiska planktonindex så visar det fortfarande inte på att det finns någrakraftiga övergödningsproblem i de undersökta sjöarna. Vidare har andelen cyanobakterieroch den totala biovolymen växtplankton inte förändrats generellt under perioden. För bottenfaunanundersöktes Oligochaeta/Chironomidae-kvoten, som ökar generellt vid övergödningför att syrgashalten blir låg och/eller den organiska belastningen hög på sjöbotten.För kvoten sker inga generella förändringar, dock sker det förändringar när sjöarna delasupp i sjötyp. Det är svårt att hitta någon generell förklaring till dessa förändringar, men lokalaoch mer ingående analyser kan möjligen hitta förklaringar till dessa förändringar i O/Ckvoten. Det saknas mycket biologiska provtagningar i det datamaterial som låg till grundför denna studie, för vattenkemin finns det till exempel ca 170 sjöar, men för biologin endastca 50 sjöar som kan inkluderas i utvärderingen. Med tanke på de stora förändringar somsker i vattenfärg och sulfatkoncentrationer så skulle övergripande analyser av både bottenfaunaoch växtplankton vara av stor betydelse för miljöövervakningen av våra sjöar ochvattendrag. Sammanfattningsvis har klimatförändringarna i form av temperaturökningar och förändradenederbördsmönster påverkat våra sjöar och vattendrag under perioden 1995-2014.Men även andra faktorer, såsom den minskande sulfatdepositionen, påverkar våra sjöar ochvattendrag. Dels direkt genom högre pH och alkalinitet, men framför allt indirekt genomförändringar i exporten av TOC och järn. I förlängningen ökar denna export brunifieringenoch tillgången på kol och närsalter för djur och växter.
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| 34. |
- Ahmadpour, Doryaneh, 1973, et al.
(författare)
-
Syntaxin 5-dependent phosphorylation of the small heat shock protein Hsp42 and its role in protein quality control
- 2023
-
Ingår i: Febs Journal. - 1742-464X. ; 290:19, s. 4744-4761
-
Tidskriftsartikel (refereegranskat)abstract
- The small heat shock protein Hsp42 and the t-SNARE protein Sed5 have central roles in the sequestration of misfolded proteins into insoluble protein deposits in the yeast Saccharomyces cerevisiae. However, whether these proteins/processes interact in protein quality control (PQC) is not known. Here, we show that Sed5 and anterograde trafficking modulate phosphorylation of Hsp42 partially via the MAPK kinase Hog1. Such phosphorylation, specifically at residue S215, abrogated the co-localization of Hsp42 with the Hsp104 disaggregase, aggregate clearance, chaperone activity, and sequestration of aggregates to IPOD and mitochondria. Furthermore, we found that Hsp42 is hyperphosphorylated in old cells leading to a drastic failure in disaggregation. Old cells also displayed a retarded anterograde trafficking, which, together with slow aggregate clearance and hyperphosphorylation of Hsp42, could be counteracted by Sed5 overproduction. We hypothesize that the breakdown of proper PQC during yeast aging may, in part, be due to a retarded anterograde trafficking leading to hyperphosphorylation of Hsp42.
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| 35. |
- Aldrin, Emilia, 1982-, et al.
(författare)
-
Nordisk namnforskning 2016 : Sverige
- 2017
-
Ingår i: Namn och bygd. - Uppsala : Kungl. Gustav Adolfs akademien för svensk folkkultur. - 0077-2704. ; 105, s. 148-156
-
Forskningsöversikt (övrigt vetenskapligt/konstnärligt)
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| 36. |
- Almstedt, Karin, 1980-, et al.
(författare)
-
Amyloid fibrils of human prion protein are spun and woven from morphologically disordered aggregates
- 2009
-
Ingår i: Prion. - Austin : Landes Bioscience Journals. - 1933-6896 .- 1933-690X. ; 3:4, s. 224-235
-
Tidskriftsartikel (refereegranskat)abstract
- Propagation and infectivity of prions in human prionopathies are likely associated with conversion of the mainly α-helical human prion protein, HuPrP, into an aggregated form with amyloid-like properties. Previous reports on efficient conversion of recombinant HuPrP have used mild to harsh denaturing conditions to generate amyloid fibrils in vitro. Herein we report on the in vitro conversion of four forms of truncated HuPrP (sequences 90-231 and 121-231 with and without an N-terminal hexa histidine tag) into amyloid-like fibrils within a few hours by using a protocol (phosphate buffered saline solutions at neutral pH with intense agitation) close to physiological conditions. The conversion process monitored by thioflavin T, ThT, revealed a three stage process with lag, growth and equilibrium phases. Seeding with preformed fibrils shortened the lag phase demonstrating the classic nucleated polymerization mechanism for the reaction. Interestingly, comparing thioflavin T kinetics with solubility and turbidity kinetics it was found that the protein initially formed non-thioflavionophilic, morphologically disordered aggregates that over time matured into amyloid fibrils. By transmission electron microscopy and by fluorescence microscopy of aggregates stained with luminescent conjugated polythiophenes (LCPs); we demonstrated that HuPrP undergoes a conformational conversion where spun and woven fibrils protruded from morphologically disordered aggregates. The initial aggregation functioned as a kinetic trap that decelerated nucleation into a fibrillation competent nucleus, but at the same time without aggregation there was no onset of amyloid fibril formation. The agitation, which was necessary for fibril formation to be induced, transiently exposes the protein to the air-water interface suggests a hitherto largely unexplored denaturing environment for prion conversion.
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| 37. |
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| 38. |
- Andersson, Per, Professor, 1964-, et al.
(författare)
-
Editorial : Spring 2018
- 2018
-
Ingår i: Nordic Journal of Vocational Education and Training. - Linköping : Linköping University Electronic Press. - 2242-458X. ; 8:1, s. iii-v
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Welcome to a new volume of the Nordic Journal of Vocational Education and Training. In this first issue of 2018 we are proud to present a new associate editor of our journal. Associate professor Hedvig Skonhoft Johannesen from OsloMet - Oslo Metropolitan University in Norway has joined the editorial group, and we look forward to fruitful cooperation with the journal. In this issue of NJVET we have seven contributions ￜ six peer-reviewed research articles and one magazine article ￜ from Sweden, Norway, and Denmark. The topics of the articles address assessment in empirical and analytical approaches, VET studentsￜ as well as teachersￜ boundary learning, digital storytelling as an approach to vocational didactics, drop out from vocational education, and finally the quality of vocational education.
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| 39. |
- Andersson, Per, Professor, 1964-, et al.
(författare)
-
Editorial: Autumn 2018
- 2018
-
Ingår i: Nordic Journal of Vocational Education and Training. - Linköping : Linköping University Electronic Press. - 2242-458X. ; 8:2, s. iii-v
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 40. |
- Andersson, Per, Professor, 1964-, et al.
(författare)
-
Editorial: Nordic research on vocational education and training
- 2017
-
Ingår i: Nordic Journal of Vocational Education and Training. - Linköping : Linköping University Electronic Press. - 2242-458X. ; , s. iii-v
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Welcome to a new issue of the Nordic Journal of Vocational Education and Training. We continue to develop an open forum for research on vocational and professional education and training, with a particular focuson the Nordic con-texts. Our journal is published online, open access, and there are no submission or article processing charges, which means that anyone with access to the Inter-net also has access to the research findings we present.
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| 41. |
- Andersson, Per, Professor, 1964-, et al.
(författare)
-
Editorial: Spring 2019
- 2019
-
Ingår i: Nordic Journal of Vocational Education and Training. - Linköping : Linköping University Electronic Press. - 2242-458X. ; 9:2, s. iii-vi
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 42. |
- Andersson, Peter, et al.
(författare)
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Low symptomatic load in Crohn's disease with surgery and medicine as complementary treatments
- 1998
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Ingår i: Scandinavian Journal of Gastroenterology. - : Informa Healthcare. - 0036-5521 .- 1502-7708. ; 33:4, s. 423-429
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The treatment of Crohn's disease has changed owing to the recognition of its chronicity. Medical maintenance treatment and limited resections have evolved as major concepts of management, regarded as complementary, and both aim at reducing the symptoms.Methods: We investigated the symptomatic load in Crohn's disease as reflected in a cross-sectional study of the symptom index, physicians' assessment, and the patients' perception of health. A cohort of 212 patients from the primary catchment area and 125 referred patients were studied.Results: Of catchment area patients, 83% were receiving medication, and the annual rate of abdominal surgery was 5.7%. Corresponding figures for the referred patients were 82% and 10.3%. According to the symptom index, 87% of catchment area patients were in remission or had only mild symptoms; according to the physicians' assessment, 90% were. The patients' median perception of health was 90% of perfect health according to the visual analogue scale. The figures were similar for referred patients, except that referrals were considered more diseased by the physician.Conclusion: The great majority of patients with Crohn's disease are able to live in remission or experience only mild symptoms.
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| 43. |
- Andersson, Per, Professor, 1964-, et al.
(författare)
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Lärare för vuxna
- 2020. - 1
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Ingår i: Om vuxenutbildning och vuxnas studier. - Lund : Studentlitteratur AB. - 9789144133294 ; , s. 165-185
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Hur går det till att bli lärare för vuxna? Vilka krav på kompetens finns för denna yrkesgrupp? Vad innebär det att vara lärare för vuxna i olika utbildningsformer och utifrån att deltagaren är just vuxen? Förutsättningarna för lärare i den kommunala vuxenutbildningen (komvux), yrkeshögskolan, folkhögskolan respektive studieförbunden varierar när det gäller bland annat kompetenskrav, uppdrag och handlingsutrymme. Att deltagarna är vuxna innebär ofta en större åldersspridning än i utbildning för barn och ungdomar, vilket också för med sig en större variation i bakgrunder och erfarenheter. Samtidigt handlar lärarens samspel med sina deltagare om relationer med andra vuxna och i den meningen jämbördiga medmänniskor. Allt detta innebär olika utmaningar och dilemman i arbetet.
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| 44. |
- Andersson, Peter, 1957-, et al.
(författare)
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Surgery for Crohn colitis over a twenty-eight-year period : fewer stomas and the replacement of total colectomy by segmental resection
- 2002
-
Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 37:1, s. 68-73
-
Tidskriftsartikel (refereegranskat)abstract
- Background: This study describes how surgery for Crohn colitis developed between 1970 and 1997, towards the end of which period limited resection and medical maintenance treatment was introduced.Methods: A cohort of 211 patients with Crohn colitis (115 population-based), of which 84 had a primary colonic resection (42 population-based), was investigated regarding indication for surgery, the time from diagnosis to operation, type of primary colonic resection, risk for permanent stoma and medication over four 7-year periods.Results: Comparison of the periods 1970-90 and 1991-97 revealed that active disease as an indication for surgery decreased from 64% to 25% ( P < 0.01) while stricture as an indication increased from 9% to 50% ( P < 0.001). Median time from diagnosis to operation increased from 3.5 to 11.5 years ( P < 0.01). Proctocolectomy or colectomy fell from 68.8% to 10% of the primary resections, whereas segmental resection increased from 31.2% to 90%. At the end of the first 7-year period, 26% had medical maintenance treatment, steroids or azathioprine taken by 7%. Corresponding figures for the last period were 70% and 49%. Patients diagnosed during the last two time-periods had less risk for surgery ( P = 0.017), permanent stoma ( P < 0.01) and total colectomy ( P < 0.01). Findings were similar in the population-based cohort.Conclusions: Current management of Crohn colitis implies a longer period between diagnosis and surgery, a reduced risk for surgery and permanent stoma, and the replacement of total colectomy by segmental resection.
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| 45. |
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| 46. |
- Andersson, Roland, et al.
(författare)
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Repeated clinical and laboratory examinations in patients with an equivocal diagnosis of appendicitis
- 2000
-
Ingår i: World Journal of Surgery. - : Springer Science and Business Media LLC. - 0364-2313 .- 1432-2323. ; 24:4, s. 479-485
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Tidskriftsartikel (refereegranskat)abstract
- In-hospital observation with repeated clinical examinations is commonly used in patients with an equivocal diagnosis of appendicitis. It is not known if repeated measurements of temperature and laboratory examinations have any diagnostic importance in this situation. The importance of repeated measurements of the body temperature, white blood cell (WBC) and differential cell counts, C-reactive protein concentration (CRP) and of the surgeon's repeated assessments was prospectively analyzed in 420 patients with an equivocal diagnosis of appendicitis at admission who were reexamined after a median of 6 hours of observation. The final diagnosis was appendicitis in 137 patients. After observation the inflammatory response was increasing among patients with appendicitis and decreasing among patients without appendicitis. The variables discriminating power for appendicitis consequently increased, from an area under the receiver operating characteristic (ROC) curve of 0.56 to 0.77 at admission, to 0.75 to 0.85 after observation. The ROC area of the surgeons' clinical assessment increased from 0.69 to 0.89. The WBC and differential cell counts were the best discriminators at the repeat examination. The change in the variables between the observations had weak discriminating power and had no additional importance in addition to the actual level at the repeat examination. To conclude, the diagnostic information of the temperature and laboratory examinations increased after observation. Repeated controls of the body temperature and laboratory examinations are therefore useful in the management of patients with equivocal signs of appendicitis, but the result of the examinations must be integrated with the clinical assessment.
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| 47. |
- Andersson, Roland, et al.
(författare)
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Why does the clinical diagnosis fail in suspected appendicitis?
- 2000
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Ingår i: European Journal of Surgery. - 1102-4151 .- 1741-9271. ; 166:10, s. 796-802
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To identify systematic errors in surgeons' estimations of the importance of diagnostic variables in the decision to explore patients with suspected appendicitis. Design: Prospective case series. Setting: Two emergency departments, Sweden. Patients: 496 patients with suspected appendicitis on admission, of whom 194 had a correct operation for appendicitis and 59 had a negative exploration. Main outcome measures: Predictors of a negative exploration expressed as the odds ratio (OR) for negative exploration. Variables influence on the decision to operate, expressed as the OR for operation, compared with the true diagnostic importance, expressed as the OR for appendicitis. Results: Predictors of negative explorations were high ratings in variables describing pain and tenderness (patient's perceived pain, abdominal tenderness, rebound tenderness, guarding or rectal tenderness), weak or absent inflammatory response, female sex, long duration of symptoms and absence of vomiting, with OR of 1.8-3.0. Pain and tenderness had too strong an influence on the decision to operate whereas the lack of an inflammatory response, no vomiting, and long duration of symptoms were not given enough attention. There was no sex difference in the proportion of patients with non-surgical abdominal pain (NSAP) who were operated on, but NSAP was more common and appendicitis less common among women, leading to a larger proportion of negative appendicectomies among women. Conclusion: Negative explorations in patients with suspected appendicitis are related to systematic errors in the clinical diagnosis with too strong an emphasis on pain and tenderness, and too little attention paid to duration of symptoms and objective signs of inflammation. Rectal tenderness is not a sign of appendicitis. The risk of diagnostic errors is similar in men and women.
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| 48. |
- Anfelter, P, et al.
(författare)
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The effect of percutaneous dilatation of renal arterial stenosis on captopril renography in hypertension
- 2005
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Ingår i: Blood Pressure. - : Informa UK Limited. - 0803-7051 .- 1651-1999. ; 14:6, s. 359-365
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Tidskriftsartikel (refereegranskat)abstract
- Background. The clinical effects of percutaneous transluminal renal artery angioplasty (PTRA) in patients with renal vascular stenosis and hypertension is controversial. Methods. We consecutively recruited all 23 patients referred for evaluation of renovascular hypertension that eventually underwent unilateral PTRA, to be investigated with captopril MAG3 renography (CR), both before and after the endovascular procedure. Data were evaluated on an intention-to-treat basis. Results. We found that the relative MAG3 clearance of the stenotic kidney increased (from 29.9 ± 14% to 35.1 ± 14%, p=0.01) and that the creatinine levels fell following the intervention (from 110 ± 19 to 99 ± 17 μmol/l, p=0.0003). Blood pressure levels were also lowered (from 173 ± 32/93 ± 17 to 158 ± 31/86 ± 15 mmHg, p<0.006) while the mean number of anti-hypertensive drugs was unchanged following PTRA (2.9 ± 1.4 before and 2.8 ± 1.3 drugs after the intervention, respectively, p-0.6). Conclusion. This prospective trial showed statistically significant improvements of individual kidney function as measured by CR and blood pressure in subjects with suspected renovascular hypertension treated with PTRA. Although the endovascular procedure was found to be safe, the magniture of the absolute improvements was rather modest. © 2005 Taylor & Francis.
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| 49. |
- Annerbo, Maria, 1967-
(författare)
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Calcium Homeostasis in Patients with Graves' Disease
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Patients with Graves´ Disease (GD) have a higher risk of developing more severe and prolonged hypocalcaemia after total thyroidectomy (TT) than patients who undergo surgery for benign atoxic goitre. Since TT is the most effective treatment for GD, it is crucial to identify mechanisms for postoperative hypocalcaemia. The aim of this thesis was to study the mechanisms of calcium metabolism in patients with GD.It is safe to operate on GD patients with TT. Results in Paper I showed fewer recurrences and equal complication rates compared to patients who underwent subtotal thyroidectomy (ST). The transient lowering of PTH seen in the hypocalcaemic patients was fully restored one month after surgery (Papers II and V).The calcium-sensing receptor (CaSR) is crucial for maintaining plasma calcium, and single nucleotide polymorphisms (SNPs) in the gene may alter the sensing function. Thus, we analysed SNPs in CaSR in GD patients (Paper II) and showed that they had a more left-shifted calcium-PTH set-point compared to controls, implicating higher sensitivity. This is also supported by the results in the group of postoperatively hypocalcaemic patients. They already had lower plasma calcium preoperatively (Papers II, IV and V) and lacked the T/G G/A G/C, a haplotype shown in Paper III to have a close relationship to higher p-calcium levels. Moreover, a lack of the T allele in rs1801725 was seen in the group of patients needing permanent treatment with calcium and vitamin D, i.e. > 12 months, (paper V).Patients who became hypocalcaemic (p-calcium < 2.00 mmol/L) on day one postoperatively, had lower preoperative levels of thyroid stimulating hormone (TSH) and higher levels of T3, this was also applied to the patient groups requiring temporary or permanent postoperative treatment (Papers II and V). In addition, hypocalcaemic patients treated for less than six months with anti-thyroid drugs had higher levels of bone metabolism markers CTX and P1NP than normocalcaemic patients (Paper V).In conclusion, the postoperative period of hypocalcaemia seen in patients with GD is a complex medical condition, caused by a combination of surgical trauma, different SNPs in CaSR, and high bone metabolism related to preoperative thyroid metabolism.
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| 50. |
- Antoni, Per, et al.
(författare)
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A chemoselective approach for the accelerated synthesis of well-defined dendritic architectures
- 2007
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Ingår i: Chemical Communications. - : Royal Society of Chemistry (RSC). - 1359-7345 .- 1364-548X. ; :22, s. 2249-2251
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Tidskriftsartikel (refereegranskat)abstract
- A chemoselective and layered growth approach has been developed for the synthesis of dendrimers, combining Click chemistry with traditional esterification/etherification reactions, without the need for activation steps and with excellent overall yields.
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