| 1171. |
- Svensson, Mats, 1960, et al.
(författare)
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Nervenzellschäden bei Schleudertraumen. Tierexperimentelle Untersuchungen
- 1998
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Ingår i: Orthopäde. ; :27, s. 820-826
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Tidskriftsartikel (refereegranskat)abstract
- Die mechanische Belastung der Halswirbelsäule (HWS) bei Autounfällen verursacht ofteine Reihe von Halsverletzungen, die unterdem Begriff Schleudertrauma zusammengefaût werden. Mehrere dieser Symptomekönnen möglicherweise durch Verletzungenim Bereich der Nervenwurzeln der HWS erklärt werden. Die Hypothese wurde aufgestellt,daû während der Extensions- und Flexionsbewegungendes Halses, aufgrund vonhämodynamischen Auswirkungen, ¾nderungendes inneren Volumens des Halswirbelkanalskurzzeitige Druckveränderungenim ZNS verursachen und daû dadurch Gewebeschäden durch die mechanische Belastungder Nervenwurzel entstehen. Um dieHypothese zu überprüfen, wurden anästhesierteSchweine einem experimentellenSchleudertrauma mit Extensions-, FlexionsundSeitneigungsbewegungen ausgesetzt.Die traumatische Belastung wurde unterhalbeiner Stufe gehalten, bei der eine Halswirbelfrakturstattfinden könnte. Während derBelastung wurde der Pulsdruck im Halswirbelkanalgemessen. In diesem Zusammenhangergaben sich Hinweise einer Dysfunktionder Zellmembran bei Nervenzellkörpernder Spinalganglien. Die ganglionären Verletzungenkönnen möglicherweise einige dermit Weichteilverletzungen des Halses nachAutounfällen einhergehenden Symptomeerklären. Um die Situation bei einem Auffahrunfallzu simulieren, wurde der Kopf desSchweines rückwärts vom Torso weggezogen.Dabei wurde festgestellt, daû die ganglionären Verletzungen zu einem sehr frühenZeitpunkt während der Halsbewegungenstattfinden und zwar in der Phase, in der dieBewegung von der Retraktion zur Extensionwechselt. Bei einer ähnlichen, jedoch statischenBelastung des Halses wurden keineganglionären Verletzungen bei den Schweinenfestgestellt. Dies ist ein Hinweis darauf,daû diese Verletzungen durch dynamischeFaktoren verursacht werden und bietet somitweitere Unterstützung für die Druckhypothese.Auf der Basis eines theoretischen Modellswurden Kriterien für Halsverletzungen(neck injury criterion = NIC) entwickelt. Esweist darauf hin, daû das Risiko von ganglionären Verletzungen am Punkt der maximalenHalsretraktion durch die unterschiedlichehorizontale Beschleunigung und Geschwindigkeitzwischen Kopf und oberemTorso bestimmt wird.
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| 1172. |
- Svensson, Magnus, et al.
(författare)
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Validating microscopic colitis (MC) in Swedish pathology registers
- 2018
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Ingår i: Scandinavian Journal of Gastroenterology. - : Taylor & Francis. - 0036-5521 .- 1502-7708.
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Microscopic colitis (MC), encompassing collagenous colitis (CC) and lymphocytic colitis (LC), is a diagnosis which relies on histopathologic criteria. This report examines the validity of having a diagnosis of MC in Swedish pathology registers.METHODS: We reviewed patient charts from 215 randomly selected individuals from 15 pathology departments in five healthcare regions in Sweden with a relevant histopathology code for MC on colon biopsies. Information on clinical symptoms and laboratory data were obtained from medical chart review. We obtained sufficient data on 211 individuals for calculating positive predictive values (PPVs) for MC.RESULTS: In total, 200/211 patients with a histopathology diagnosis of MC were confirmed as also having a clinical diagnosis of MC after chart review, yielding a PPV of 95% (95%CI =91-97%). The PPV for CC was 95% (95%CI =87-98%) and 85% for LC (95%CI =78-90%). The median age at biopsy was 67 years (range 17-90 years), and 72% (n = 154) were women. The most common symptoms in patients with MC histopathology were diarrhea (96% of patients), weight loss (24%) and abdominal pain (13%). Four percent (4/111) of patients with available data on stool culture were positive for gastrointestinal pathogens (none had Clostridium difficile). In 81 patients with available celiac serology, five (6%) were positive. Twenty-six percent of all patients had at least one other autoimmune disease, the most frequent being hypothyroidism (8%) and celiac disease (6%).CONCLUSIONS: This study found a high validity for MC as recorded in Swedish pathology registers.
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| 1173. |
- Svensson, Nina, 1988-, et al.
(författare)
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Effects of Geofencing on Exhaust Emissions and Noise : A combined Test Track and Traffic Simulation Study
- 2024
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Ingår i: Proceedings of the 25th International Transport & Air Pollution (TAP) and the 3rd Shipping & Environment (S&E) Conference. - : Publications Office of the European Union. - 9789268128107 ; , s. 51-56
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Konferensbidrag (refereegranskat)abstract
- Speed-limiting geofencing has been suggested as a mean to improve both traffic safety and to reduce emissions from road transport. However, there is limited knowledge of the effect of geo-fencing on air quality and noise. In this project we have performed a combined measurement and modelling study to evaluate the effects of geofencing on traffic performance, traffic safety (described elsewhere), exhaust and noise emissions.
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| 1174. |
- Svensson, Nina, 1988-, et al.
(författare)
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Measurements and Modelling of Offshore Wind Profiles in a Semi-Enclosed Sea
- 2019
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Ingår i: Atmosphere. - : MDPI AG. - 2073-4433. ; 10:4
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Tidskriftsartikel (refereegranskat)abstract
- A conically scanning, continuous-wave LIDAR is placed on an island in the central Baltic Sea with large open-water fetch, providing wind and turbulence profiles up to 300 m height. LIDAR and Weather Research and Forecasting (WRF) profiles from one year are used to characterize the marine boundary layer, at the same time performing an evaluation of the WRF model against LIDAR measurements with a focus on low-level jet representation. A good agreement is found between the average wind speed profile in WRF and LIDAR, with the largest bias occurring during stable conditions. The LLJ frequency is highest in May with frequency of occurrence ranging between 18% and 27% depending on the method of detection. Most of the LLJs occur during nighttime, indicating that most of them do not have local origin. For cases with simultaneous LLJs in both data sets the WRF agrees well with the LIDAR. In many cases, however, the LLJ is misplaced in time or space in the WRF simulations compared to the LIDAR. This shows that models still must be improved to capture mesoscale effects in the coastal zone.
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| 1175. |
- (Svensson) Nyman, Erika, 1976-, et al.
(författare)
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Effects of amniotic fluid on human keratinocyte gene expression : Implications for wound healing
- 2022
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Ingår i: Experimental dermatology. - Chichester, United Kingdom : Wiley-Blackwell. - 0906-6705 .- 1600-0625. ; 31:5, s. 764-774
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Tidskriftsartikel (refereegranskat)abstract
- Cutaneous wounds can lead to huge suffering for patients. Early fetal wounds have the capacity to regenerate without scar formation. Amniotic fluid (AF), containing hyaluronic acid (HA), may contribute to this regenerative environment. We aimed to analyse changes in gene expression when human keratinocytes are exposed to AF or HA. Human keratinocytes were cultured to subconfluence, starved for 12 h and then randomised to be maintained in (1) Dulbeccos modified Eagles medium (DMEM), (2) DMEM with 50% AF, or (3) DMEM with 50% fetal calf serum (FCS). Transcriptional changes were analysed using microarray and enriched with WebGestalt and Enrichr. Additionally, eight diagnostic genes were analysed using semiquantitative real-time PCR to investigate epidermal differentiation and cellular stress after HA exposure as an alternative for AF exposure. The AF and FCS treatments resulted in enrichment of genes relating to varied aspects of epidermal and keratinocyte biology. In particular, p63-, AP1- and NFE2L2- (Nrf2) associated genes were found significantly regulated in both treatments. More genes regulated by FCS treatment were associated with inflammatory signalling, whilst AF treatment was dominantly associated with molecular establishment of epidermis and lipid metabolic activity. HA exposure mostly resulted in gene regulation that was congruent with the AF microarray group, with increased expression of ITGA6 and LOR. We conclude that AF exposure enhances keratinocyte differentiation in vitro, which suggests that AF constituents can be beneficial for wound-healing applications.
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| 1176. |
- Svensson, Olof, et al.
(författare)
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An evaluation of 2D-wavelet filters for estimation of differences in textures of pharmaceutical tablets
- 2006
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Ingår i: Chemometrics and Intelligent Laboratory Systems. - : Elsevier BV. - 0169-7439 .- 1873-3239. ; 84:1-2, s. 3-8
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Tidskriftsartikel (refereegranskat)abstract
- In chemical imaging spectra are acquired over a surface with one spectrum for each pixel of the image. The obtained spectra usually carry a mixture of chemical and physical information. One may view the properties that vary over the image, the mean spectral magnitude from separate wavelength intervals, or better, PCA scores may be shown as images.In this way a multitude of images are compressed to a few images that in the PCA case are representative for the main variation in the sample images. These images may be viewed manually and deductions as to e.g. differences in homogeneity can be made. At an increased rate of samples, the observer will have difficulties coping with the repetitive work and different observers will most likely have slightly different interpretations. In order to automate the process of estimation of e.g. homogeneity and particle density, image filters can be used to calculate a small set of texture descriptors for each image. Calculations based on the 2D versions of the discrete wavelet transform (DWT) using Daubechies 14 and the dual tree complex wavelet transform (DT-CWT) using near-symmetric 13, 19 tap filters in combination with q-shift 14, 14 tap filters were evaluated for this purpose.The aim with this work is to evaluate texture descriptors based on a combination of 2D-wavelet filters and energy, i.e. l(1)-norm, calculations for each wavelet scale. These descriptors are then used as observations for overview in e.g. PCA. In this way the texture differences can be ranked by ordinary use of PCA or PLS.This method is tested on multivariate near infrared images of pharmaceutical tablets. Score images are selected to represent variations of the aggregate density and sizes in the compressed tablets. Images are shifted and rotated to compare shift and rotational independence of the texture descriptors.
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| 1177. |
- Svensson, Peter, et al.
(författare)
-
Den undranslösa företagsekonomin
- 2020
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Ingår i: Om undran inför företagsekonomin. - 9789173591560
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 1178. |
- Svensson, Per-Edvin, et al.
(författare)
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Characterization and reduction of noise in dynamic PET data using masked volumewise principal component analysis
- 2011
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Ingår i: Journal of Nuclear Medicine Technology. - : Society of Nuclear Medicine. - 0091-4916 .- 1535-5675. ; 39:1, s. 27-34
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Tidskriftsartikel (refereegranskat)abstract
- Masked volumewise principal component (PC) analysis (PCA) is used in PET to distinguish structures that display different kinetic behaviors after administration of a tracer. When masked volumewise PCA was introduced, one article proposed noise prenormalization because of temporal and spatial variations of the noise between slices. However, the noise prenormalization proposed in that article was applicable only to datasets reconstructed using filtered backprojection (FBP). The study presented in this article aimed at developing a new noise prenormalization that is applicable to datasets regardless of whether they were reconstructed with FBP or an iterative reconstruction algorithm, such as ordered-subset expectation maximization (OSEM).Methods: A phantom study was performed to investigate differences in the expectation values and SDs of datasets reconstructed with FBP and OSEM. A novel method, higher-order PC noise prenormalization, was suggested and evaluated against other prenormalization methods on clinical datasets.Results: Masked volumewise PCA of data reconstructed with FBP was much more dependent on an appropriate prenormalization than was analysis of data reconstructed with OSEM. Higher-order PC noise prenormalization showed an overall good performance with both FBP and OSEM reconstructions, whereas the other prenormalization methods performed well with only 1 of the 2 methods.Conclusion: Higher-order PC noise prenormalization has potential for improving the results from masked volumewise PCA on dynamic PET datasets independent of the type of reconstruction algorithm.
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| 1179. |
- Svensson, Pär-Johan
(författare)
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Molecular studies on Hirschsprung disease and 'Ondine's curse'
- 1999
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis is based on molecular studies of two diseases that arise from dysfunction of, defective migration or inappropriate apoptosis of neural crest derived cells: Hirschsprung disease (HSCR) and "Ondine's curse" (congenital central hypoventilation syndrome, CCHS). The neural crest (NC) is a condensation of pluripotent cells of ectodermal origin. Neural crest cells migrate during fetal life to form, among other tissues and cell types, the sympathetic part of the autonomic nervous system. Sympathetic neuroblasts invade the gastrointestinal canal in a cranial to caudal direction, cluster and differentiate to become the neuronal intestinal ganglia of Meissner and Auerbach. NC cells also form the cholinergic pathways in the ventral medulla. Patients with HSCR lack neuronal ganglia in the hindgut. This results in poor co-ordination of propulsion and a contracted distal segment with subsequent constipation or intestinal obstruction. The disease affects one in 5000 live births and males are more often affected than females. Familial occurrence and an increased risk for siblings indicate a genetic cause of HSCR. The studies on HSCR (Papers I-III) were based on 69 unrelated HSCR patients comprising 7 familial and 62 sporadic cases, accrued from the Stockholm region. Being a population-based study, there were no bias of ascertainment towards familial or long segment aganglionosis. Mutational screening was performed with single stranded conformation polymorphism analysis (SSCP) in candidate genes for NC development: the RET, endothelin receptor-B (EDNRB) and endothelin-3 (EDN-3) genes. Five germline mutations were detected in the RET gene: two frameshift and one missense mutation (C620R) typical for multiple endocrine neoplasia type 2A (MEN 2A) in familial cases; two missense mutations in sporadic cases. A girl with HSCR and MEN2A mutation developed medullary thyroid carcinoma at the age of 13 years (paper I). Six sporadic HSCR cases had one out of three different missense mutations in the EDNRB gene. Five of the mutations were inherited, one de novo. In all families with an inherited mutation, there were multiple cases of constipation in the family branch segregating the EDNRB mutation. These could constitute cases of subclinical Hirschsprung disease (paper II). An additional non-consanguineous family segregated two identical EDNRB mutations (G57S), as well as a RET mutation (R982C). The male proband, with short segment HSCR carries the RET and is heterozygous for the EDNRB mutation. The mother and sister both carry the RET mutation. The mother is heterozygous, the sister homozygous for the EDNRB mutation. The female carriers of both mutations were clinically unaffected. This suggests a possible additional sex-dependent modifying locus in this family (paper III). The original population-based cohort of 69 cases was expanded to 75 for the EDN-3 study described in paper IV. Among these 75 cases, a male patient with non-syndromic HSCR was found to carry a heterozygous frameshift mutation, predicted to result in haplo-insufficiency. The mutation is inherited from the mother, who has a history of moderate constipation (paper IV). "Ondine's curse" is a disease characterised by the absence of autonomous breathing due to dysfunction of neural crest derived cells in the ventral medulla. An association with HSCR is reported in 15-50% of "Ondine's curse" patients. 25 cases, four with associated HSCR, where nonselectively ascertained and screened for mutations in the RET, glial cell line-derived neurotrophic factor (GDNF), EDNRB, EDN-3 and EDN-1 genes. A missense mutation was detected in the RET gene in a patient with late onset "Ondine's curse" and hyperphagia. This mutation was inherited from the clinically unaffected father. A mutation was also detected in the EDN-1 gene 3'UTR domain, in a patient with classical isolated "Ondine's curse" (paper V).
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| 1180. |
- Svensson, Ragni, et al.
(författare)
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Bokförlag i Lund: 1900-tal och 2000-tal
- 2017
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Ingår i: En lundensisk litteraturhistoria : Lunds universitet som litterärt kraftfält - Lunds universitet som litterärt kraftfält. - 1401-1301. - 9789170612503 ; 2018, s. 388-392
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Bokkapitel (populärvet., debatt m.m.)
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