| 1. |
- Kim, Jeong-Lim, et al.
(författare)
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Fish consumption and school grades in Swedish adolescents: a study of the large general population.
- 2010
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Ingår i: Acta Paediatrica. - 1651-2227. ; 99, s. 72-7
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Tidskriftsartikel (refereegranskat)abstract
- AIM: To study the associations between fish intake and academic achievement as cognitive parameter among Swedish adolescents. METHODS: In 2000, a questionnaire including respiratory items, socioeconomic conditions and dietary information was mailed to all schoolchildren (n = 18 158), aged 15 and living in Västra Götaland region of Sweden. The questionnaire was returned by 10 837 subjects. One year later, the total school grades for each subject who had completed the questionnaire and who included their full personal identification number were obtained from the national registers. Multiple linear regression models were applied to evaluate the association between fish intake and academic grades among 9448 schoolchildren, while adjusting for potential confounders, e.g. parents' education. RESULTS: Grades were higher in subjects with fish consumption once a week compared with subjects with fish consumption of less than once a week (reference group) [increment in estimate 14.5, 95% confidence interval (CI) 11.8-17.1]. Grades were even higher in subjects with fish consumption of more than once a week compared with the reference group (increment in estimate 19.9, 95% CI 16.5-23.3). In the model stratified for parents' education, there were still higher grades among subjects with frequent fish intake in all educational strata (p < 0.01). CONCLUSION: Frequent fish intake among schoolchildren may provide benefits in terms of academic achievement.
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| 2. |
- Nordblom, Jonathan, et al.
(författare)
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FGF1 containing biodegradable device with peripheral nerve grafts induces corticospinal tract regeneration and motor evoked potentials after spinal cord resection
- 2012
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Ingår i: Restorative Neurology and Neuroscience. - 0922-6028 .- 1878-3627. ; 30:2, s. 91-102
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Repairing the spinal cord with peripheral nerve grafts (PNG) and adjuvant acidic fibroblast growth factor (FGF1) has previously resulted in partial functional recovery. To aid microsurgical placement of PNGs, a graft holder device was previously developed by our group. In hope for a translational development we now investigate a new biodegradable graft holder device containing PNGs with or without FGF1.Methods: Rats were subjected to a T11 spinal cord resection with subsequent repair using twelve white-to-grey matter oriented PNGs prepositioned in a biodegradable device with or without slow release of FGF1. Animals were evaluated with BBB-score, electrophysiology and immunohistochemistry including anterograde BDA tracing.Results: Motor evoked potentials (MEP) in the lower limb reappeared at 20 weeks after grafting. MEP responses were further improved in the group treated with adjuvant FGF1. Reappearance of MEPs was paralleled by NF-positive fibers and anterogradely traced corticospinal fibers distal to the injury. BBB-scores improved in repaired animals.Conclusions: The results continue to support that the combination of PNGs and FGF1 may be a regeneration strategy to reinnervate the caudal spinal cord. The new device induced robust MEPs augmented by FGF1, and may be considered for translational research.
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| 3. |
- Vikström, Linnea, et al.
(författare)
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Vaccine-induced correlate of protection against fatal COVID-19 in older and frail adults during waves of neutralization-resistant variants of concern : an observational study
- 2023
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Ingår i: The Lancet Regional Health. - : Elsevier. - 2666-7762. ; 30
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: To inform future preventive measures including repeated vaccinations, we have searched for a clinically useful immune correlate of protection against fatal COVID-19 among nursing homes residents.METHODS: We performed repeated capillary blood sampling with analysis of S-binding IgG in an open cohort of nursing home residents in Sweden. We analyzed immunological and registry data from 16 September 2021 to 31 August 2022 with follow-up of deaths to 30 September 2022. The study period included implementation of the 3rd and 4th mRNA monovalent vaccine doses and Omicron virus waves.FINDINGS: A total of 3012 nursing home residents with median age 86 were enrolled. The 3rd mRNA dose elicited a 99-fold relative increase of S-binding IgG in blood and corresponding increase of neutralizing antibodies. The 4th mRNA vaccine dose boosted levels 3.8-fold. Half-life of S-binding IgG was 72 days. A total 528 residents acquired their first SARS-CoV-2 infection after the 3rd or the 4th vaccine dose and the associated 30-day mortality was 9.1%. We found no indication that levels of vaccine-induced antibodies protected against infection with Omicron VOCs. In contrast, the risk of death was inversely correlated to levels of S-directed IgG below the 20th percentile. The death risk plateaued at population average above the lower 35th percentile of S-binding IgG.INTERPRETATION: In the absence of neutralizing antibodies that protect from infection, quantification of S-binding IgG post vaccination may be useful to identify the most vulnerable for fatal COVID-19 among the oldest and frailest. This information is of importance for future strategies to protect vulnerable populations against neutralization resistant variants of concern.FUNDING: Swedish Research Council, SciLifeLab via Knut and Alice Wallenberg Foundation, VINNOVA. Swedish Healthcare Regions, and Erling Persson Foundation.
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| 4. |
- Åberg, Maria A I, 1972, et al.
(författare)
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Fish intake of Swedish male adolescents is a predictor of cognitive performance.
- 2009
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Ingår i: Acta paediatrica (Oslo, Norway : 1992). - : Wiley. - 1651-2227 .- 0803-5253. ; 98:3, s. 555-60
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Tidskriftsartikel (refereegranskat)abstract
- AIM: Fish intake is reported to positively influence cognitive performance in infants and the elderly. In a longitudinal cohort study, we evaluated how fish consumption related to later cognitive performance in healthy young male adolescents. METHODS: In 2000, all 15-year-olds (n = 18 158; 9260 males) in the western region of Sweden were requested to complete an extensive questionnaire with items on diseases, fish consumption and socioeconomic status. Questionnaire data from the male responders (n = 4792, response rate 52%) were linked with records on subsequent intelligence test performance at age 18 from the Swedish Military Conscription Register (n = 3972). Multivariate linear models were used to estimate associations between fish intake and cognitive performance, adjusting for potential confounders. RESULTS: There was a positive association between the number of times having fish meals per week at age 15 and cognitive performance measured 3 years later. Fish consumption of more than once per week compared to less than once per week was associated with higher stanine scores in combined intelligence (0.58 units; 95% confidence interval 0.39, 0.76), in verbal performance (0.45; 0.27, 0.63) and in visuospatial performance (0.50; 0.31, 0.69). The association between fish consumption and the 3 intelligence scores was the same in lowly and highly educated groups. This indicates that education did not influence the association between the frequency of fish meals consumed and cognitive performance. CONCLUSION: Frequent fish intake at age 15 was associated with significantly higher cognitive performance 3 years later.
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| 5. |
- Abrahamsson, Pernilla, 1972-, et al.
(författare)
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Comparison between outcome of surface and intraparenchymatous sampling using microdialysis in an experimental liver ischemia model
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Introduction. We recently have shown that samples from MD probes placed on the surface of the heart reflect metabolic events in the myocardium. This new interesting observation challenges us to consider whether surface application of MD applies to other parenchymatous organs and their surfaces. Material and methods. In thirteen anesthetized pigs transient liver ischemia was achieved by occlusion of arterial and venous inflow to the liver. Two probes on liver surface, and two in parenchyma were perfused with a flow rate of 1 µL/min (n=13). An identical set up was used for probes with a flow rate of 2 µL/min (n=9). Samples were collected for every 15 minute period during 60 minutes of baseline, 45 minutes of ischemia and 60 minutes of reperfusion. Lactate, glucose, pyruvate and glycerol were analysed in MD samples. We focused on relative changes in the present paper. Results. There was a strong agreement in relative lactate and glucose levels between probes placed on liver surface and parenchyma. No significant differences in relative changes of lactate and glucose levels were seen between samples from surface probes and probes in liver parenchyma during equilibration, baseline, ischemia or reperfusion with a flow rate of 1 µL/min. Conclusion. MD sampling applied on the liver surface is a new application area for the MD technique, and may be used to monitor liver metabolism both during physiological and pathophysiological conditions.
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| 6. |
- Abrahamsson, Pernilla, et al.
(författare)
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Outcome of microdialysis sampling on liver surface and parenchyma
- 2016
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Ingår i: Journal of Surgical Research. - : Elsevier BV. - 0022-4804 .- 1095-8673. ; 200:2, s. 480-487
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Tidskriftsartikel (refereegranskat)abstract
- Background: To investigate whether surface microdialysis (μD) sampling in probes covered by a plastic film, as compared to noncovered and to intraparenchymatous probes, would increase the technique's sensitivity for pathophysiologic events occurring in a liver ischemia-reperfusion model. Placement of μD probes in the parenchyma of an organ, as is conventionally done, may cause adverse effects, e.g., bleeding, possibly influencing outcome.Methods: A transient ischemia-reperfusion model of the liver was used in six anesthetized normoventilated pigs. μD probes were placed in the parenchyma and on the liver surface. Surface probes were either left uncovered or were covered by plastic film.Results: Lactate and glucose levels were significantly higher in plastic film covered probes than in uncovered surface probes throughout the ischemic period. Glycerol levels were significantly higher in plastic film covered probes than in uncovered surface probes at 30 and 45 min into ischemia.Conclusions: Covering the μD probe increases the sensibility of the μD–technique in monitoring an ischemic insult and reperfusion in the liver. These findings confirm that the principle of surface μD works, possibly replacing need of intraparenchymatous placement of μD probes. Surface μD seemingly allows, noninvasively from an organ's surface, via the extracellular compartment, assessment of intracellular metabolic events. The finding that covered surface μD probes allows detection of local metabolic changes earlier than do intraparenchymatous probes, merit further investigation focusing on μD probe design.
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| 7. |
- Abrahamsson, Pernilla, et al.
(författare)
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Surface microdialysis sampling : a new approach described in a liver ischaemia model
- 2012
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Ingår i: Clinical Physiology and Functional Imaging. - : Wiley-Blackwell. - 1475-0961 .- 1475-097X. ; 32:2, s. 99-105
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Tidskriftsartikel (refereegranskat)abstract
- We recently have shown that samples from microdialysis (MD) probes placed on the surface of the heart reflect metabolic events in the myocardium. This new interesting observation challenges us to consider whether surface application of MD applies to other parenchymatous organs and their surfaces. In 13 anesthetized pigs, transient liver ischaemia was achieved by occlusion of arterial and venous inflow to the liver. Two probes on liver surface and two in parenchyma were perfused with a flow rate of 1 mu l per min (n = 13). An identical set-up was used for probes with a flow rate of 2 mu l per min (n = 9). Samples were collected for every 15-min period during 60 min of baseline, 45 min of ischaemia and 60 min of reperfusion. Lactate, glucose, pyruvate and glycerol were analysed in MD samples. We focused on relative changes in the present study. There was a strong agreement in relative lactate and glucose levels between probes placed on liver surface and those on parenchyma. No significant differences in relative changes in lactate and glucose levels were seen between samples from surface probes and probes in liver parenchyma during equilibration, baseline, ischaemia or reperfusion with a flow rate of 1 mu l per min. MD sampling applied on the liver surface is a new application area for the MD technique and may be used to monitor liver metabolism during both physiological and pathophysiological conditions.
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| 8. |
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| 9. |
- Bladh, Oscar, et al.
(författare)
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Comparison of SARS-CoV-2 spike-specific IgA and IgG in nasal secretions, saliva and serum
- 2024
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Ingår i: Frontiers in Immunology. - : Frontiers Media S.A.. - 1664-3224. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Several novel vaccine platforms aim at mucosal immunity in the respiratory tract to block SARS-CoV-2 transmission. Standardized methods for mucosal sample collection and quantification of mucosal antibodies are therefore urgently needed for harmonized comparisons and interpretations across mucosal vaccine trials and real-world data.Methods: Using commercial electrochemiluminescence antibody panels, we compared SARS-CoV-2 spike-specific IgA and IgG in paired saliva, nasal secretions, and serum from 1048 healthcare workers with and without prior infection.Results: Spike-specific IgA correlated well in nasal secretions and saliva (r>0.65, p<0.0001), but the levels were more than three-fold higher in nasal secretions as compared to in saliva (p<0.01). Correlations between the total population of spike-specific IgA and spike-specific secretory IgA (SIgA) were significantly stronger (p<0.0001) in nasal secretions (r=0.96, p<0.0001) as opposed to in saliva (r=0.77, p<0.0001), and spike-specific IgA correlated stronger (p<0.0001) between serum and saliva (r=0.73, p<0.001) as opposed to between serum and nasal secretions (r=0.54, p<0.001), suggesting transudation of monomeric spike specific IgA from the circulation to saliva. Notably, spike-specific SIgA had a markedly higher SARS-CoV-2 variant cross-binding capacity as compared to the total population of spike specific IgA and IgG in both nasal secretions, saliva and serum, (all p<0.0001), which emphasizes the importance of taking potential serum derived monomeric IgA into consideration when investigating mucosal immune responses.Discussion: Taken together, although spike-specific IgA can be reliably measured in both nasal secretions and saliva, our findings imply an advantage of higher levels and likely also a larger proportion of SIgA in nasal secretions as compared to in saliva. We further corroborate the superior variant cross-binding capacity of SIgA in mucosal secretions, highlighting the potential protective benefits of a vaccine targeting the upper respiratory tract.
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| 10. |
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| 11. |
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Christensson, J, et al.
(författare)
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Effective-interaction approach to the many-boson problem
- 2009
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Ingår i: Physical Review A - Atomic, Molecular, and Optical Physics. - 2469-9926 .- 2469-9934 .- 1050-2947. ; 79:1, s. 012707-
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Tidskriftsartikel (refereegranskat)abstract
- We show that the convergence behavior of the many-body numerical diagonalization scheme for strongly interacting bosons in a trap can be significantly improved by the Lee-Suzuki method adapted from nuclear physics: One can construct an effective interaction that acts in a space much smaller than the original Hilbert space. In particular for short-ranged forces and strong correlations, the method offers a good estimate of the energy and the excitation spectrum, at a computational cost several orders of magnitude smaller than that required by the standard method.
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| 16. |
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| 17. |
- Edlund, Jonas, et al.
(författare)
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Social norms and tax compliance
- 2002
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Ingår i: Swedish Economic Policy Review. - 1400-1829. ; 9:1, s. 201-228
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Tidskriftsartikel (refereegranskat)
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| 18. |
- Engstrand, Johanna, et al.
(författare)
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Influence of water content on hardening and handling of a premixed calcium phosphate cement
- 2013
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Ingår i: Materials science & engineering. C, biomimetic materials, sensors and systems. - : Elsevier BV. - 0928-4931 .- 1873-0191. ; 33:1, s. 527-531
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Tidskriftsartikel (refereegranskat)abstract
- Handling of calcium phosphate cements is difficult, where problems often arise during mixing, transferring tosyringes, and subsequent injection. Via the use of premixed cements the risk of handling complications is reduced. However, for premixed cements to work in a clinical situation the setting time needs to be improved. The objective of this study is to investigate the influence of the addition of water on the properties of premixed cement. Monetite-forming premixed cements with small amounts of added water (less than 6.8 wt.%) were prepared and the influence on injectability, working time, setting time and mechanical strength was evaluated. The results showed that the addition of small amounts of water had significant influence on the properties of the premixed cement. With the addition of just 1.7 wt.% water, the force needed to extrude the cement from a syringe was reduced from 107 (±15)N to 39 (±9)N, the compression strength was almost doubled, and the setting time decreased from 29 (±4)min to 19 (±2)min, while the working time remained 5 to 6 h. This study demonstrates the importance of controlling the water content in premixed cement pastes and how water can be used to improve the properties of premixed cements.
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| 19. |
- Engstrand, Thomas, et al.
(författare)
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Development of a bioactive implant for repair and potential healing of cranial defects
- 2014
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Ingår i: Journal of Neurosurgery. - 0022-3085 .- 1933-0693. ; 120:1, s. 273-277
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Tidskriftsartikel (refereegranskat)abstract
- The repair of complex craniofacial bone defects is challenging and a successful result is dependent on the size of the defect, quality of the soft tissue covering the defect, and choice of reconstruction method. The objective of this study was to develop a bioactive cranial implant that could provide a permanent reconstructive solution to the patient by stimulating bone healing of the defect. In this paper the authors report on the feasibility and clinical results of using such a newly developed device for the repair of a large traumatic and therapy-resistant cranial bone defect. The patient had undergone numerous attempts at repair, in which established methods had been tried without success. A mosaic-designed device was manufactured and implanted, comprising interconnected ceramic tiles with a defined calcium phosphate composition. The clinical outcome 30 months after surgery revealed a restored cranial vault without postoperative complications. Computed tomography demonstrated signs of bone ingrowth. Examination with combined 18F-fluoride PET and CT provided further evidence of bone healing of the cranial defect.
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| 20. |
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| 21. |
- Eriksson, Jonas, et al.
(författare)
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Strategy to develop a MAO-A-resistant 5-hydroxy-L-[beta-C-11]tryptophan isotopologue based on deuterium kinetic isotope effects
- 2014
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Ingår i: EJNMMI Research. - : Springer Science and Business Media LLC. - 2191-219X. ; 4:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundThe serotonin precursor 5-hydroxy-L-[β-11C]tryptophan ([11C]HTP) is in clinical use for localization of neuroendocrine tumors and has been suggested as a proxy marker for pancreatic islet cells. However, degradation by monoamine oxidase-A (MAO-A) reduces retention and the contrast to non-endocrine tissue.MethodsA synthesis method was developed for 5-hydroxy-L-[β-11C2H]tryptophan ([11C]DHTP), an isotopologue of [11C]HTP, labeled with 11C and 2H at the β-position adjacent to the carbon involved in MAO-A decarboxylation. MAO-A-mediated degradation of [11C]DHTP was evaluated and compared to non-deuterated [11C]HTP.Results[11C]DHTP was synthesized with a radiochemical purity of >98%, radioactivity of 620 ± 190 MBq, and deuterium (2H or 2H2) incorporation at the β-position of 22% ±5%. Retention and resistance to MAO-A-mediated degradation of [11C]DHTP were increased in cells but not in non-human primate pancreas.ConclusionsPartial deuteration of the β-position yields improved resistance to MAO-A-mediated degradation in vitro but not in vivo.
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| 22. |
- Eriksson, Jonas, et al.
(författare)
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Synthesis of [11C]/[13C]acrylamides by palladium-mediated carbonylation
- 2007
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Ingår i: European Journal of Organic Chemistry. - : Wiley. - 1434-193X .- 1099-0690. ; :3, s. 455-461
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Tidskriftsartikel (refereegranskat)abstract
- Two methods are presented for the synthesis of acrylamides labelled with C-11 (beta(+), t(1/2) = 20.4 min) and C-11 in the carbonyl position. In the first method, [1-C-11]acrylic acid is synthesised from [C-11]carbon monoxide by palladium-mediated hydroxy-carbonylation of acetylene. The labelled carboxylic acid is converted into the acyl chloride and subsequently treated with amine to yield N-benzyl[carbonyl(11)C]acrylamide, The second method utilizes [C-11]carbon monoxide in a palladium-mediated carbonylative cross-coupling of vinyl halides and amines. A higher radiochemical yield is achieved with the latter method and the amount of amine needed is decreased to 1/20. The C-11-labelled acrylamides were isolated in up to 81 % decay-corrected radiochemical yield. Starting from 10 +/- 0.5GBq of [C-11]carbon monoxide, N-benzyl[carbonyl-C-11]acrylamide was obtained in 4 min with a specific radioactivity of 330 +/- 4 GBq mu mol-(1). Co-labelling with C-11 and C-13 enabled confirmation of the labelled position by C-13 NMR spectroscopy.
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| 23. |
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| 24. |
- Forsell, Claes, et al.
(författare)
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Preoperative Topical Hypothermia used in Prolonged Severe Lower Limb Ischemia to Avoid Ischemic Damage - The First Clinical Experience
- 2013
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Ingår i: International Journal of Biomedical Science. - 1550-9702 .- 1555-2810. ; 9:3, s. 181-184
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Tidskriftsartikel (refereegranskat)abstract
- Severe lower limb ischemia TASC IIB/III with sensory and motor neurologic deficiencies leads to prolonged hospital care, amputation, and death in 20-70 % of cases. We present our first clinical experience of the use of preoperative topical hypothermia to improve muscular viability in these patients. Two hours after onset of symptoms, six 4-liter plastic bags were filled with snow and packed against the ischemic leg which was protected from frost injury by a layer of towels. After surgical revascularization four hours later muscular and neural functions in the leg were completely restored. A maximum serum myoglobin of 6500 ng/L (median 12000 ng/L in similar but untreated patients) postoperatively decreased to 1400 ng/L after 27 hours.
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| 25. |
- Forssen, Christian, 1974, et al.
(författare)
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The Ab Initio No-core Shell Model
- 2009
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Ingår i: Few-Body Systems. - : Springer Science and Business Media LLC. - 1432-5411 .- 0177-7963. ; 45:2, s. 111-
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Konferensbidrag (refereegranskat)abstract
- This contribution reviews a number of applications of the ab initio no-core shell model (NCSM) within nuclear physics and beyond. We will highlight a nuclear-structure study of the A = 12 isobar using a chiral NN + 3NF interaction. In the spirit of this workshop we will also mention the new development of the NCSM formalism to describe open channels and to approach the problem of nuclear reactions. Finally, we will illustrate the universality of the many-body problem by presenting the recent adaptation of the NCSM effective-interaction approach to study the many-boson problem in an external trapping potential with short-range interactions.This article is based on the presentation by C. Forssén at the Fifth Workshop on Critical Stability, Erice, Sicily.
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| 26. |
- Gabrielsson, Jonas, 1975-, et al.
(författare)
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Corporate Governance in Small and Medium Enterprises
- 2020. - 1
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Ingår i: Advances in Corporate Governance. - Oxford : Oxford University Press. - 9780191898501 - 9780198866367 ; , s. 82-110
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Bokkapitel (refereegranskat)abstract
- The objective of this chapter is to discuss corporate governance in relation to small and medium size enterprises (SMEs). We examine the regulatory environment by reviewing corporate governance codes developed for SMEs as well as literature and research on corporate governance in SMEs. From this stance, we discuss the specificities of SMEs, including the multiple ideologies that often co-exist in these firms. Finally, the extended team production model of corporate governance is introduced. The model offers a balanced perspective on the full range of value-adding stakeholders in SMEs, and provides a set of guiding principles to improve the value creation potential of their corporate governance arrangements © Oxford University Press 2021
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| 27. |
- Gallinetti, Sara, 1985-, et al.
(författare)
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Titanium reinforced calcium phosphate improves bone formation and osteointegration in ovine calvaria defects : a comparative 52 weeks study
- 2021
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Ingår i: Biomedical Materials. - : Institute of Physics Publishing (IOPP). - 1748-6041 .- 1748-605X. ; 16:3
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Tidskriftsartikel (refereegranskat)abstract
- In a 52 week ovine calvaria implantation model, the restoration of cranial defects with a bare titanium mesh (Ti-mesh) and a titanium mesh embedded in a calcium phosphate (CaP-Ti) were evaluated in seven animals. During the study, no major clinical abnormalities were observed, and all sheep presented a normal neurologic assessment. Blood and cerebrospinal fluid analysis, made at termination, did not show any abnormalities. No indentation of the soft tissue was observed for either test article; however, the Ti-mesh burr-hole covers were associated with filling of the calvarial defect by fibrous tissue mainly. Some bone formation was observed at the bottom of the created defect, but no significant bone was formed in the proximity of the implant. The defect sites implanted with CaP-Ti were characterized by a moderate degradation of the calcium phosphate (CaP) that was replaced by mature bone tissue. Calcium-phosphate-filled macrophages were observed in all animals, indicating that they might play a vital role in osteogenesis. The newly formed bone was present, especially at the bony edges of the defect and on the dura side. Integration of the Ti-mesh in a CaP improved bone formation and osteointegration in comparison to a bare Ti-mesh.
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| 28. |
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| 29. |
- Grimby-Ekman, Anna, 1967, et al.
(författare)
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Pain could negatively affect school grades - Swedish middle school students with low school grades most affected
- 2018
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- © 2018 Grimby-Ekman et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Recurrent headache, abdominal and musculoskeletal pain are common in adolescents and it is therefore important to understand their impact on the transitional period from childhood to adulthood. However, studies of the prevalence over time and implications on educational outcomes are still limited, especially regarding multiple pain symptoms. The present study material consists of questionnaire surveys, completed in 2000 and 2008, including two study populations of 9th grade adolescents aged 15 living in West Sweden (n = 20 877). Pain symptoms and demographic variables were based on self-reports from the questionnaires, and school grades were obtained from Statistics Sweden after the student had finished their 9th grade. Between 2000 and 2008, the prevalence of abdominal pain increased among Swedish adolescents (largest increase in girls); the prevalence of headache increased only in girls; the prevalence of pain in upper body decreased only in boys. School grades were significantly lower among those with headache or abdominal pain. Among students with low school grades (10th percentile) the estimated difference between those having any of the symptoms or none were -27 school grade units (95% confidence interval for girls (-27.8; -26.0), for boys (-27.6; -25.5). Both symptoms being present pronounced the association. Low parental education increased the negative effect of symptoms on school grades, most pronounced in the group with the lowest grades. In conclusion, identification of pain symptoms may improve academic achievements, especially in students with multiple symptoms and with parents having low education. Further intervention studies are need.
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| 30. |
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| 31. |
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| 32. |
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| 33. |
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| 34. |
- Guillet, Claire, et al.
(författare)
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Bone formation beyond the skeletal envelope using calcium phosphate granules packed into a collagen pouch-a pilot study
- 2023
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Ingår i: Biomedical Materials. - : Institute of Physics Publishing (IOPP). - 1748-6041 .- 1748-605X. ; 18:3
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Tidskriftsartikel (refereegranskat)abstract
- In this proof-of-concept, bone neoformation beyond the skeletal envelope is explored by using a collagen pouch (n = 6) packed with calcium phosphate (CaP) granules placed over the frontal bone in sheep (n = 3). At 13 weeks, macroscopic examination showed specimens covered by an adherent fibrinous envelope with slight vascularization. Histology revealed colonization of the implant by newly formed woven bone and fibrous connective tissue. Surface osteoblasts as well as material-filled macrophages, lymphocytes, polymorphonuclear cells and giant cells were also found in large quantities surrounding the newly formed bone tissue inside the collagen pouch. On the side facing the recipient bone, the collagen membrane had to a large extent been resorbed and bridging bone formation was clearly visible between the test article and recipient bone. On the other side facing soft tissue, the collagen pouch remained intact with a visible fibrous capsule. This study demonstrated that the use of a collagen sleeve as a container for CaP granules allows for good neoformation beyond the skeletal envelope with bridging bone formation clearly visible between the test article and recipient bone. Additionally, in this model, macrophages rather than osteoclasts appear to modulate CaP granule resorption and remodeling into new bone. This construct opens new perspectives for treatment methods that could be used for bone augmentation and restoration of cranio-maxillofacial defects and malformations.
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| 35. |
- Hammar, Linus, et al.
(författare)
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Symphony : Integrerat planeringsstöd för statlig havsplanering utifrån en ekosystemansats
- 2018
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Symphony beräknar den kumulativa, sammanlagda, miljöpåverkan i havet. Beräkningarna baseras på en transparent vetenskaplig metod som framförallt baseras på nationellt täckande kartor över ekologiska värden och belastningar från mänskliga verksamheter.Genom Symphony kan havsplanernas effekt på miljöpåverkan bedömas och resultatet påverkar havsplanernas utformning. Denna rapport är framtagen för havsplaneringens samrådsskede 2018.Mycket nyttigt i bilagornaDu kan tända och släcka lager i den första kartan i bilaga 1 och 2 för att utforska materialet. Då behöver du en pdf-läsare som stödjer den funktionen, till exempel Adobe Reader eller Foxit Reader.Till rapporten hör flera bilagorMetadata visar båda kartorna från de olika påverkanslagerna och beskriver hur de data som påverkanslagerna representerar har tagits fram och skalats.Gröna kartan visar alla ekologiska värden som ligger till grund för kartorna.Känslighetsmatrisen visar hur de ekologiska värdena påverkas av belastningarna.Nuläget utan havsplan (bilagor 4 abc)Nuläget med havsplan, alltså havsplanens påverkan om den hade implementerats direkt (bilagor 5 abc)Utblick på hur miljöpåverkan utvecklats till år 2030 utan havsplan (bilagor 6 abc)
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| 36. |
- Hansson, Emma, et al.
(författare)
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Neuropeptide levels in Dercum's disease (adiposis dolorosa).
- 2012
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Ingår i: Reumatismo. - 0048-7449. ; 64:3, s. 134-141
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Tidskriftsartikel (refereegranskat)abstract
- Dercum's disease (adiposis dolorosa) is characterised by adiposity and chronic pain in the adipose tissue. It has been proposed that conditions encompassing chronic pain have altered concentrations of neuropeptides involved in pain transmission. The aim of this investigation was to examine whether patients with Dercum's disease have abnormal concentrations of different neuropeptides. In cerebrospinal fluid (CSF) and in plasma (P) from 53 patients with Dercum's disease substance P-like immunoreactivity (SP-LI), neuropeptide Y-like immunoreactivity (NPY-LI), b-endorphin-like immunoreactivity (b-END-LI), calcitonin gene-related peptidelike immunoreactivity (CGRP-LI), met-enkephalin-like immunoreactivity (m-ENK-LI), vasoactive intestinal polypeptide-like immunoreactivity (VIP-LI), somatostatin (SOM-LI), g2-melanocyte-stimulating hormone-like immunoreactivity (g2-MSH-LI), and dynorphin-like immunoreactivity (DYN-LI) were measured. Three of the substances were also measured in a control group. The CSF concentration of SP was statistically significantly lower in the Dercum group than in the control group, whereas NPY-LI and b-END-LI were borderline statistically significantly lower and higher, respectively, in Dercum patients compared to controls. Compared with reference values, CSF-MSH-LI levels were slightly elevated and CSF-NPY-LI levels were slightly lowered in the Dercum group. The other substances in both CSF and plasma were within the reference values with a high degree of statistical significance. In conclusion, altered levels of neuropeptides that have previously been seen in different pain conditions cannot clearly be demonstrated in Dercum's disease.
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| 37. |
- Havervall, Sebastian, et al.
(författare)
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Antibody responses after a single dose of ChAdOx1 nCoV-19 vaccine in healthcare workers previously infected with SARS-CoV-2
- 2021
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Ingår i: EBioMedicine. - : Elsevier BV. - 2352-3964. ; 70
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Tidskriftsartikel (refereegranskat)abstract
- Background: Recent reports demonstrate robust serological responses to a single dose of messenger RNA (mRNA) vaccines in individuals previously infected with SARS-CoV-2. Data on immune responses following a single-dose adenovirus-vectored vaccine expressing the SARS-CoV-2 spike protein (ChAdOx1 nCoV-19) in individuals with previous SARS-CoV-2 infection are however limited, and current guidelines recommend a two-dose regimen regardless of preexisting immunity. Methods: We compared RBD-specific IgG and RBD-ACE2 blocking antibodies against SARS-CoV-2 wild type and variants of concern following two doses of the mRNA vaccine BNT162b2 in SARS-CoV-2 naive healthcare workers (n=65) and a single dose of the adenovector vaccine ChAdOx1 nCoV-19 in 82 healthcare workers more than (n=45) and less than (n=37) 11 months post mild SARS-CoV-2 infection at time of vaccination. Findings: The post-vaccine levels of RBD-specific IgG and neutralizing antibodies against the SARS-CoV-2 wild type and variants of concern including Delta lineage 1.617.2 were similar or higher in participants receiving a single dose of ChAdOx1 nCoV-19 vaccine post SARS-CoV-2 infection (both more than and less than 11 months post infection) compared to SARS-CoV-2 naive participants who received two doses of BNT162b2 vaccine. Interpretation: Our data support that a single dose ChAdOx1 nCoV-19 vaccine that is administered up to at least 11 months post SARS-CoV-2 infection serves as an effective immune booster. This provides a possible rationale for a single-dose vaccine regimen. (C) 2021 The Author(s). Published by Elsevier B.V.
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| 38. |
- Havervall, Sebastian, et al.
(författare)
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Impact of SARS-CoV-2 infection on vaccine-induced immune responses over time
- 2022
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Ingår i: Clinical & Translational Immunology (CTI). - : Wiley. - 2050-0068. ; 11:4
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Tidskriftsartikel (refereegranskat)abstract
- Objective. To determine the long-term impact of prior SARS-CoV-2 infection on immune responses after COVID-19 vaccination. Methods. Using longitudinally collected blood samples from the COMMUNITY study, we determined binding (WHO BAU mL(-1)) and neutralising antibody titres against ten SARS-CoV-2 variants over 7 months following BNT162b2 in SARS-CoV-2-recovered (n = 118) and SARS-CoV-2-naive (n = 289) healthcare workers with confirmed prior SARS-CoV-2 infection. A smaller group with (n = 47) and without (n = 60) confirmed prior SARS-CoV-2 infection receiving ChAdOx1 nCoV-19 was followed for 3 months. SARS-CoV-2-specific memory T-cell responses were investigated in a subset of SARS-CoV-2-naive and SARS-CoV-2-recovered vaccinees. Results. Vaccination with both vaccine platforms resulted in substantially enhanced T-cell responses, anti-spike IgG responses and neutralising antibodies effective against ten SARS-CoV-2 variants in SARS-CoV-2-recovered participants as compared to SARS-CoV-2-naive participants. The enhanced immune responses sustained over 7 months following vaccination. Conclusion. These findings imply that prior SARS-CoV-2 infection should be taken into consideration when planning booster doses and design of current and future COVID-19 vaccine programmes.
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| 39. |
- Havervall, Sebastian, et al.
(författare)
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Robust humoral and cellular immune responses and low risk for reinfection at least 8 months following asymptomatic to mild COVID-19
- 2022
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Ingår i: Journal of Internal Medicine. - : John Wiley & Sons. - 0954-6820 .- 1365-2796. ; 291:1, s. 72-80
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Tidskriftsartikel (refereegranskat)abstract
- Background: Emerging data support detectable immune responses for months after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and vaccination, but it is not yet established to what degree and for how long protection against reinfection lasts.Methods: We investigated SARS-CoV-2-specific humoral and cellular immune responses more than 8 months post-asymptomatic, mild and severe infection in a cohort of 1884 healthcare workers (HCW) and 51 hospitalized COVID-19 patients. Possible protection against SARS-CoV-2 reinfection was analyzed by a weekly 3-month polymerase chain reaction (PCR) screening of 252 HCW that had seroconverted 7 months prior to start of screening and 48 HCW that had remained seronegative at multiple time points.Results: All COVID-19 patients and 96% (355/370) of HCW who were anti-spike IgG positive at inclusion remained anti-spike IgG positive at the 8-month follow-up. Circulating SARS-CoV-2-specific memory T cell responses were detected in 88% (45/51) of COVID-19 patients and in 63% (233/370) of seropositive HCW. The cumulative incidence of PCR-confirmed SARS-CoV-2 infection was 1% (3/252) among anti-spike IgG positive HCW (0.13 cases per 100 weeks at risk) compared to 23% (11/48) among anti-spike IgG negative HCW (2.78 cases per 100 weeks at risk), resulting in a protective effect of 95.2% (95% CI 81.9%-99.1%).Conclusions: The vast majority of anti-spike IgG positive individuals remain anti-spike IgG positive for at least 8 months regardless of initial COVID-19 disease severity. The presence of anti-spike IgG antibodies is associated with a substantially reduced risk of reinfection up to 9 months following asymptomatic to mild COVID-19.
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| 40. |
- Hulsart-Billstrom, Gry, 1982-, et al.
(författare)
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Guiding bone formation using semi‐onlay calcium phosphate implants in an ovine calvarial model
- 2022
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Ingår i: Journal of Tissue Engineering and Regenerative Medicine. - : Hindawi Limited. - 1932-6254 .- 1932-7005. ; 16:5, s. 435-447
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Tidskriftsartikel (refereegranskat)abstract
- The restoration of cranio-maxillofacial deformities often requires complex reconstructive surgery in a challenging anatomical region, with abnormal soft tissue structures and bony deficits. In this proof-of-concept, the possibility of vertical bone augmentation was explored by suspending hemispherically shaped titanium-reinforced porous calcium phosphate (CaP) implants (n = 12) over the frontal bone in a sheep model (n = 6). The animals were euthanized after week 13 and the specimens were subject to micro-computed tomography (μCT) and comprehensive histological analysis. Histology showed that the space between implant and the recipient bone was filled with a higher percentage of newly formed bone (NFB) versus soft tissue with a median of 53% and 47%, respectively. Similar results were obtained from the μ-CT analysis, with a median of 56% NFB and 44% soft tissue filling the void. Noteworthy, significantly higher bone-implant contact was found for the CaP (78%, range 14%–94%) versus the Titanium (29%, range 0%–75%) portion of the implant exposed to the surrounding bone. The histological analysis indicates that the CaP replacement by bone is driven by macrophages over time, emphasized by material-filled macrophages found in close vicinity to the CaP with only a small number of single osteoclasts found actively remodeling the NFB. This study shows that CaP based implants can be assembled with the help of additive manufacturing to guide vertical bone formation without decortification or administration of growth factors. Furthermore, it highlights the potential disadvantage of a seamless fit between the implant and the recipient's bone.
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| 41. |
- Hulsart-Billström, Gry, et al.
(författare)
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Calcium phosphates compounds in conjunction with hydrogel as carrier for BMP-2 : A study on ectopic bone formation in rats
- 2011
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Ingår i: Acta Biomaterialia. - : Elsevier BV. - 1742-7061 .- 1878-7568. ; 7:8, s. 3042-3049
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Tidskriftsartikel (refereegranskat)abstract
- Current treatment of fractures often involves the use of bone graft or bone morphogenetic proteins (BMP) to induce fracture healing, especially in patients with a compromised healing capacity. BMP has to be delivered in conjunction with a carrier. Unfortunately, there are drawbacks and limitations with current carriers, including their bovine origin which carries the risk of an immunological response. The physical properties also limit the use to open surgical procedures, as it cannot be injected. New carriers with improved properties are therefore needed. The aim of this study was to assess the ectopic bone forming capability of various calcium phosphate compounds when used in conjunction with a hydrogel as the carrier for BMP-2. Five different ceramic additives were tested, including beta-tricalcium phosphate and four types of hydroxyapatite (HAP) (nanoHAP, HAP, clods of HAP >100 mu m, and the biomimetic HAP Ostim35 (R)). The compounds were injected into the thigh muscle of rats, where it formed a gel in situ. After 4 weeks bone formation was evaluated by peripheral quantitative computed tomography and histology. The major finding was that the 20 nm nanoHAP yielded a higher bone density than the other additives (P = 0.0008, ANOVA with Tukey's multiple comparison test). We hypothesize that the higher bone density induced by nanoHAP might be due to nanocrystals of calcium phosphate acting as direct building blocks for biomineralization.
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| 42. |
- Ivarsson, Jonas, 1976, et al.
(författare)
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Role of requests and communication breakdowns in the coordination of teamwork: a video-based observational study of hybrid operating rooms.
- 2020
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Ingår i: BMJ Open. - : BMJ. - 2044-6055. ; 10:5
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Tidskriftsartikel (refereegranskat)abstract
- This study investigated the functional role of 'requests' in the coordination of surgical activities in the operating room (OR). A secondary aim was to describe, closely, instances of potential miscommunication to scrutinise how so-called conversational repairs were used to address and prevent mistakes.Non-participant video-based observations.Team coordination around image acquisitions (digital subtraction angiography) done during endovascular aortic repair (EVAR) procedures in a hybrid OR.The study followed and documented a total of 72 EVAR procedures, out of which 12 were video-recorded (58hours). The results were based on 12 teams operating during these recorded surgeries and specifically targeted all sequences involving controlled apnoea. In total, 115 sequences were analysed within the theoretical framework of conversation analysis.The results indicated a simple structure of communication that can enable the successful coordination of work between different team members. Central to this analysis was the distinction between immediate requests and pre-requests. The results also showed how conversational repairs became key in establishing joint understanding and, therefore, how they can function as crucial resources in safety management operations.The results suggest the possibility of devising an interactional framework to minimise problems with communication, thereby enabling the advancement of patient safety. By making the distinction between different types of requests explicit, certain ambiguities can be mitigated and some misunderstandings avoided. One way to accomplish this practically would be to tie various actions to clearer and more distinct forms of expression.
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| 43. |
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| 44. |
- Kim, Jeong-Lim, et al.
(författare)
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Trends in the prevalence of asthma, rhinitis, and eczema in 15 year old adolescents over an 8 year period
- 2014
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Ingår i: Respiratory Medicine. - : Elsevier BV. - 0954-6111. ; 108:5, s. 701-708
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Tidskriftsartikel (refereegranskat)abstract
- Background: Trends in prevalence of asthma and allergic diseases are still controversial, and rarely studied among adolescents at midpoint of puberty. Methods: In 2000, a questionnaire was mailed to adolescents (n = 18,158) attending 9th grade at school and living in Vastra Gotaland County, Sweden. Eight years later, the same questionnaire was mailed to adolescents (n = 21,651), using identical inclusion criteria as previously. Altogether, 10,837 adolescents completed the questionnaire in 2000 and 11,754 in 2008. Differences in prevalence of physician diagnosed asthma, asthma symptoms, rhinitis, and eczema between the periods were analyzed by Chi-square test. Multiple logistic regression models were performed to test for trends in prevalence of these diseases, adjusting for potential con-founders. Results: Physician diagnosed asthma and lifetime and current rhinitis were increased in 2008, while wheeze decreased (p < 0.05). Taking sex, foreign descent, body mass index, and parents' education into account, the prevalence of physician diagnosed asthma (OR 1.3 [95% CI 1.2-1.4]) and lifetime (1.7 [1.6-1.8]) and current rhinitis (1.5 [1.4-1.6]) had increased. Eczema had decreased (0.9 [0.8-0.98]). These trends were consistent in boys and girls, but more prominent in those with obesity. In physician diagnosed asthmatics, there was no change in wheeze, asthma symptoms, or asthma medication. Conclusions: The prevalence of physician diagnosed asthma has increased over the last decade, maybe due to combinations of changes in diagnostics and increased general awareness, rather than a real increase. Results showed an increase in rhinitis and a decrease in eczema. Obesity seems to have a modifying effect, which calls for further investigation. (C) 2014 Elsevier Ltd. All rights reserved.
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| 45. |
- Kvorning, N, et al.
(författare)
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Acupuncture relieves pelvic and low-back pain in late pregnancy
- 2004
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Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - : Wiley. - 1600-0412 .- 0001-6349. ; 83:3, s. 246-250
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Tidskriftsartikel (refereegranskat)abstract
- Background The study was designed to evaluate the analgesic effect and possible adverse effects of acupuncture for pelvic and low-back pain during the last trimester of pregnancy. Methods Following individual informed consent, 72 pregnant women reporting pelvic or low-back pain were randomized during pregnancy weeks 24-37 to an acupuncture group (n = 37) or to a control group (n = 35) at three maternity wards in southern Sweden. Traditional acupuncture points and local tender points (TP) were chosen according to individual pain patterns and stimulated once or twice a week until delivery or complete recovery in acupuncture patients. Control patients were given no sham stimulation. Throughout the study period each patient made weekly visual analog scale (VAS) evaluations of maximal and minimal pain intensity as well as three-point assessments of pain intensity during various activities. Results During the study period, VAS scorings of pain intensity decreased over time in 60% of patients in the acupuncture group and in 14% of those in the control group (p < 0.01). At the end of the study period, 43% of the acupuncture patients were less bothered than initially by pain during activity compared with 9% of control patients (p < 0.01). No serious adverse effects of acupuncture were found in the patients, and there were no adverse effects at all in the infants. Conclusion Acupuncture relieves low-back and pelvic pain without serious adverse effects in late pregnancy.
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| 46. |
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| 47. |
- Lewin, Susanne, et al.
(författare)
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Additively manufactured mesh-type titanium structures for cranial implants : E-PBF vs. L-PBF
- 2021
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Ingår i: Materials & design. - : Elsevier. - 0264-1275 .- 1873-4197. ; 197
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Tidskriftsartikel (refereegranskat)abstract
- A patient-specific titanium-reinforced calcium phosphate (CaP–Ti) cranial implant has recently shown promising clinical results. Currently, its mesh-type titanium structure is additively manufactured using laser beam powder bed fusion (L-PBF). Nevertheless, an electron-beam (E-PBF) process could potentially be more time efficient. This study aimed to compare the geometrical accuracy and mechanical response of thin titanium structures manufactured by L-PBF (HIPed) and E-PBF (as-printed). Tensile test (ø = 1.2 mm) and implant specimens were manufactured. Measurements by μCT revealed a deviation in cross-sectional area as compared to the designed geometry: 13–35% for E-PBF and below 2% for L-PBF. A superior mechanical strength was obtained for the L-PBF specimens, both in the tensile test and the implant compression tests. The global peak load in the implant test was 457 ± 9 N and 846 ± 40 N for E-PBF and L-PBF, respectively. Numerical simulations demonstrated that geometrical deviation was the main factor in implant performance and enabled quantification of this effect: 34–39% reduction in initial peak force based on geometry, and only 11–16% reduction based on the material input. In summary, the study reveals an uncertainty in accuracy when structures of sizes relevant to mesh-type cranial implants are printed by the E-PBF method.
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| 48. |
- Lewin, Susanne, et al.
(författare)
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Mechanical behaviour of composite calcium phosphate-titanium cranial implants : Effects of loading rate and design
- 2020
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Ingår i: Journal of The Mechanical Behavior of Biomedical Materials. - : Elsevier BV. - 1751-6161 .- 1878-0180. ; 104
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Tidskriftsartikel (refereegranskat)abstract
- Cranial implants are used to repair bone defects following neurosurgery or trauma. At present, there is a lack of data on their mechanical response, particularly in impact loading. The aim of the present study was to assess the mechanical response of a recently developed composite calcium phosphate-titanium (CaP-Ti) implant at quasi-static and impact loading rates. Two different designs were tested, referred to as Design 1 (D1) and Design 2 (D2). The titanium structures in the implant specimens were additively manufactured by a powder-bed fusion process and subsequently embedded in a self-setting CaP material. D1 was conceptually representative of the clinically used implants. In D2, the titanium structure was simplified in terms of geometry in order to facilitate the manufacturing. The mechanical response of the implants was evaluated in quasi-static compression, and in impact using a drop-tower. Similar peak loads were obtained for the two designs, at the two loading rates: 808 ± 29 N and 852 ± 34 for D1, and 840 ± 40 N and 814 ± 13 for D2. A strain rate dependency was demonstrated for both designs, with a higher stiffness in the impact test. Furthermore, the titanium in the implant fractured in the quasi-static test (to failure) but not in the impact test (to 5.75 J) for D1. For D2, the displacement at peak load was significantly lower in the impact test than in the quasi-static test. The main difference between the designs was seen in the quasi-static test results where the deformation zones, i.e. notches in the titanium structure between the CaP tiles, in D1 likely resulted in a localization of the deformation, compared to in D2 (which did not have deformation zones). In the impact test, the only significant difference between the designs was a higher maximum displacement of D2 than of D1. In comparison with other reported mechanical tests on osteoconductive ceramic-based cranial implants, the CaP-Ti implant demonstrates the highest reported strength in quasi-static compression. In conclusion, the titanium structure seems to make the CaP-Ti implant capable of cerebral protection in impact situations like the one tested in this study.
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| 49. |
- Lewin, Susanne, et al.
(författare)
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Monetite-based composite cranial implants demonstrate long-term clinical volumetric balance by concomitant bone formation and degradation
- 2021
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Ingår i: Acta Biomaterialia. - : Elsevier. - 1742-7061 .- 1878-7568. ; 128, s. 502-513
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Tidskriftsartikel (refereegranskat)abstract
- The use of calcium phosphates (CaPs) as synthetic bone substitutes should ideally result in a volumetric balance with concomitant bone formation and degradation. Clinical data on such properties is nevertheless lacking, especially for monetite-based CaPs. However, a monetite-based composite implant has recently shown promising cranial reconstructions, with both CaP degradation and bone formation. In this study, the volumetric change at the implant site was quantified longitudinally by clinical computed tomography (CT). The retrospective CT datasets had been acquired postoperatively ( n = 10), in 1-year ( n = 9) and 3-year ( n = 5) follow-ups. In the 1-year follow-up, the total volumetric change at the implant site was-8 +/- 8%. A volumetric increase (bone formation) was found in the implant-bone interface, and a volumetric decrease was observed in the central region (CaP degradation). In the subjects with 2-or 3-year follow-ups, the rate of volumetric decrease slowed down or plateaued. The reported degradation rate is lower than previous clinical studies on monetite, likely due to the presence of pyrophosphate in the monetite-based CaP-formulation. A 31-months retrieval specimen analysis demonstrated that parts of the CaP had been remodeled into bone. The CaP phase composition remained stable, with 6% transformation into hydroxyapatite. In conclusion, this study demonstrates successful bone-bonding between the CaP-material and the recipient bone, as well as a long-term volumetric balance in cranial defects repaired with the monetitebased composite implant, which motivates further clinical use. The developed methods could be used in future studies for correlating spatiotemporal information regarding bone regeneration and CaP degradation to e.g. patient demographics. Statement of significance In bone defect reconstructions, the use of calcium phosphate (CaP) bioceramics ideally results in a volumetric balance between bone formation and CaP degradation. Clinical data on the volumetric balance is nevertheless lacking, especially for monetite-based CaPs. Here, this concept is investigated for a composite cranial implant. The implant volumes were quantified from clinical CT-data: postoperatively, one year and three years postoperatively. In total,-8 +/- 8% ( n = 9) volumetric change was observed after one year. But the change plateaued, with only 2% additional decrease at the 3-year follow-up ( n = 5), indicating a lower CaP degradation rate. Osseointegration was seen at the bone-implant interface, with a 9 +/- 7% volumetric change after one year. This study presented the first quantitative spatiotemporal CT analysis of monetite-based CaPs.
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| 50. |
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