| 1. |
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| 2. |
- Johansson Wensman, Jonas, et al.
(författare)
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Visualization of Borna Disease Virus Protein Interactions with Host Proteins using in situ Proximity Ligation Assay
- 2016
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Ingår i: British journal of virology. - : ResearchersLinks Ltd. - 2055-6128. ; 3:1, s. 11-23
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Tidskriftsartikel (refereegranskat)abstract
- Borna disease virus type 1 (BDV) comprises highly conserved neurotropic non-segmented negative strand RNA-virus variants causing neurological and behavioral disorders in a wide range of mammalian animals, possibly including humans. Viral persistence in the brain has been frequently observed, however, the exact mechanisms behind BDV’s ability to establish persistence despite a prominent immune response are not known. Here we have used in situ proximity ligation assay (in situ PLA), a selective tool for studying virus-host protein-protein interactions. BDV P (phosphoprotein) and N (nucleoprotein) have previously been reported to interact with several host proteins, thereby interfering with various signaling pathways. In this study, we focused on some of these interactions (BDV P-HMGB1, BDV N/P-Cdc2). First, we used rat glioma cell cultures persistently infected with a laboratory strain of BDV (C6BV) to establish the assay. Next, in situ PLA was applied to detect BDV P in brain tissues of infected animals. Finally, protein-protein interactions were visualized in both C6BV and brain tissues of experimentally as well as naturally infected animals (rat and horse, respectively). BDV proteins and their interactions with host proteins could be shown in cell cultures (HMGB1, Cdc2) and in brain tissues of rat (HMGB1, Cdc2) and horse (Cdc2 only) infected with BDV. In this study, we have for the first time directly visualized protein-protein interactions between BDV and its host, and thereby confirmed previous data to demonstrate findings in cell cultures to be applicable also in experimentally and naturally infected animals.
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| 3. |
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| 4. |
- Abdel-Motal, Ussama M., et al.
(författare)
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Major histocompatibility complex class I binding glycopeptides for the estimation of 'empty' class I molecules
- 1995
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Ingår i: Journal of Immunological Methods. - : Elsevier BV. - 0022-1759. ; 188:1, s. 21-31
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Tidskriftsartikel (refereegranskat)abstract
- Different forms of major histocompatibility complex (MHC) class I heavy chains are known to be expressed on the cell surface, including molecules which are functionally 'empty'. Direct peptide binding to cells is obvious during sensitization of target cells in vitro for cytotoxic T lymphocyte killing and 'empty' MHC-I molecules are comparatively abundant on TAP- 1 2 peptide transporter mutant cells. In the present work we have estimated the fraction of 'empty' MHC class I molecules using glycosylated peptides and cellular staining with carbohydrate specific monoclonal antibodies. Synthetic Db and Kb binding peptides were coupled at different positions with different di- or trisaccharides, using different spacing between the carbohydrate and the peptide backbone. Binding of sugar specific mAbs was compared in ELISA and cellular assays. An optimal Db binding glycopeptide was used for comparative staining with anti-Db and anti-carbohydrate monoclonal antibodies to estimate fractions of 'empty' molecules on different T lymphoid cells. On activated normal T cells, a large fraction of Db molecules were found to be 'empty'. The functional cole of such 'empty' MHC class I molecules on T cells is presently unclear. However, on antigen presenting cells they might participate in the antigen presentation process.
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| 5. |
- Abraham-Nordling, Mirna, et al.
(författare)
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Incidence of hyperthyroidism in Sweden
- 2011
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Ingår i: European Journal of Endocrinology. - 0804-4643 .- 1479-683X. ; 165:6, s. 899-905
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: The incidence of hyperthyroidism has been reported in various countries to be 23-93/100000 inhabitants per year. This extended study has evaluated the incidence for similar to 40% of the Swedish population of 9 million inhabitants. Sweden is considered to be iodine sufficient country. Methods:All patients including children, who were newly diagnosed with overt hyperthyroidism in the years 2003-2005, were prospectively registered in a multicenter study. The inclusion criteria are as follows:clinical symptoms and/or signs of hyperthyroidism with plasma TSH concentration below 0.2 mIE/l and increased plasma levels of free/total triiodothyronine and/or free/total thyroxine. Patients with relapse of hyperthyroidism or thyroiditis were not included. The diagnosis of Graves' disease (GD), toxic multinodular goiter (TMNG) and solitary toxic adenoma (STA), smoking, initial treatment, occurrence of thyroid-associated eye symptoms/signs, and demographic data were registered. Results:A total of 2916 patients were diagnosed with de novo hyperthyroidism showing the total incidence of 27.6/100 000 inhabitants per year. The incidence of GD was 21.0/100 000 and toxic nodular goiter (TNG=STA+TMNG) occurred in 692 patients, corresponding to an annual incidence of 6.5/100 000. The incidence was higher in women compared with men (4.2:1). Seventy-five percent of the patients were diagnosed with GD, in whom thyroid-associated eye symptoms/signs occurred during diagnosis in every fifth patient. Geographical differences were observed. Conclusion:The incidence of hyperthyroidism in Sweden is in a lower range compared with international reports. Seventy-five percent of patients with hyperthyroidism had GD and 20% of them had thyroid-associated eye symptoms/signs during diagnosis. The observed geographical differences require further studies.
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| 6. |
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| 7. |
- Agarwal, PK, et al.
(författare)
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Box-trees and R-trees with near-optimal query time
- 2002
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Ingår i: Discrete & Computational Geometry. - : Springer Science and Business Media LLC. - 0179-5376 .- 1432-0444. ; 28:3, s. 291-312
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Tidskriftsartikel (refereegranskat)abstract
- A box-tree is a bounding-volume hierarchy that uses axis-aligned boxes as bounding volumes. The query complexity of a box-tree with respect to a given type of query is the maximum number of nodes visited when answering such a query. We describe several new algorithms for constructing box-trees with small worst-case query complexity with respect to queries with axis-parallel boxes and with points. We also prove lower bounds on the Worst-case query complexity for box-trees, which show that our results are optimal or close to optimal. Finally, we present algorithms to convert box-trees to R-trees, resulting in R-trees with (almost) optimal query complexity.
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| 8. |
- Agüero, Ramón, et al.
(författare)
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RRM Challenges for Non-Conventional and Low-Cost Networks in Ambient Networks
- 2005
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Konferensbidrag (refereegranskat)abstract
- This paper presents an overview of the Radio Resource Management (RRM) functionalities needed for Non-Conventional and Low-Cost Networks. These types of networks are characterized by increased cooperation between different types of networks and providers and they are believed to play a fundamental role for future wireless network networking. The paper describes three specific concepts, which latter is used to identify new RRM challenges. In addition, it identifies the relation between the RRM challenges and the Ambient Networks architecture and functionalities, in particular the multiradio resource management functionality.
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| 9. |
- Alm, Erika, et al.
(författare)
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Introduction
- 2021
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Ingår i: Pluralistic Struggles in Gender, Sexuality and Coloniality. - Cham : Palgrave Macmillan. - 9783030474324 ; , s. 1-18
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The focus of this book is on the many far from predictable transformative political processes on gender, sexuality and coloniality that grow out of the broad range of bodies and actors engaged in politics outside the hegemonic order and in everyday activities. These processes are not conducted by states, governments or transnational nongovernmental organisations; rather, they are examples of politics in-between states, organisations and national imagined communities. In this first chapter we will introduce some of the main themes, regarding these processes we in our joint research programme have worked on over the last couple of years.
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| 10. |
- Aminoff, Victoria, et al.
(författare)
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Internet-Based Cognitive Behavioral Therapy for Psychological Distress Associated With the COVID-19 Pandemic : A Pilot Randomized Controlled Trial
- 2021
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Ingår i: Frontiers in Psychology. - : Frontiers Media S.A.. - 1664-1078. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Background: The COVID-19 pandemic has been associated with various negative psychological consequences. This is a challenge for the society as regular psychological services cannot be offered to the same extent as before the pandemic. In addition to the requirement of social distancing, there is a need to adjust psychological treatment components like exposure to avoid increasing the spread of the infection. Internet-delivered cognitive behavior therapy (ICBT) has an established evidence base for a range of psychiatric problems and has been suggested as one possible approach to deal with the situation. This study aimed to conduct a randomized controlled pilot trial during the summer of 2020 with a broad focus on psychological distress and a treatment approach that tailors the intervention based on symptom profile and preferences.Methods: Following the advertisement and interview, we included 52 participants with elevated levels of psychological distress. They were randomly allocated to either a 7-week-long individually tailored ICBT (n = 26) or a wait-list control condition (n = 26). Measures of depression and quality of life were used as primary outcomes. We also included secondary outcome measures of anxiety, insomnia, trauma, stress, anger, and alcohol use. For screening, we used the CoRonavIruS Health Impact Survey (CRISIS). Results: Overall moderate to large between-group effects were found at post-treatment in favor of the treatment on measures of both depression [Beck Depression Inventory (BDI); Cohens d = 0.63; Patient Health Questionnaire (PHQ-9): d = 0.62] and anxiety [Generalized Anxiety Disorder-7-item scale (GAD-7); d = 0.82]. This was also observed for stress symptoms [Perceived Stress Scale (PSS-14); d = 1.04]. No effects were seen on measures of quality of life, insomnia, symptoms of post-traumatic stress, and anger. There was an effect on alcohol use [Alcohol Use Disorder Identification Test (AUDIT); d = 0.54], which was not of clinical relevance.Conclusion: Individually tailored ICBT shows initial promise as a way to reduce psychological problems in association with the COVID-19 pandemic. A possible limitation was that the trial was conducted when the effects of the pandemic were decreasing and when fewer people were affected by the restrictions (e.g., the summer of 2020).
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| 11. |
- Aminoff, Victoria, et al.
(författare)
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Tailored internet-based psychological treatment for psychological problems during the COVID-19 pandemic: A randomized controlled trial
- 2023
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Ingår i: Internet Interventions. - : ELSEVIER. - 2214-7829. ; 34
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Tidskriftsartikel (refereegranskat)abstract
- The COVID-19 pandemic influence mental health in both infected and non-infected populations. In this study we examined if individually tailored internet-based cognitive behavioral therapy (ICBT) could be an effective treatment for psychological symptoms related to the pandemic. Following recruitment we included 76 participants who were randomized to either a treatment group (n = 37) or a waitlist control group (n = 39). The treatment group received 8 modules (out of 16 possible) during 8 weeks with weekly therapist support. We collected data on symptoms of depression, experienced quality of life, anxiety, stress, anger, insomnia, PTSD, and alcohol use before, after the treatment and at one year follow-up. Using multiple regression analysis, group condition was found to be a statistically significant predictor for a decrease, favoring the treatment group, in symptoms of depression, insomnia, and anger with small to moderate effect sizes. The improvements remained at one year follow-up. Group condition did not significantly predict changing symptoms regarding experienced quality of life, anxiety, stress, PTSD and alcohol use. Findings indicate that ICBT is an effective intervention for some psychological symptoms associated with the COVID-19 pandemic. There is a need for further studies on mechanisms of change and on tailored ICBT for problems associated with crises like the pandemic.
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| 12. |
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| 13. |
- Andéhn, Mikael, 1982-
(författare)
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Place-of-Origin Effects on Brand Equity : Explicating the evaluative pertinence of product categories and association strength
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The country-of-origin effect - the alteration of judgment derived from an association to a place, is a much studied phenomenon with great potential implications for brand management and international marketing. However, in light of criticism towards the lack of conceptual development the extant literature, the relevance of the effect has been brought into question.Through an exploration of the psychology of the association between brands and places, the country-of-origin effect is reimagined focusing on the role of association strength as well as how the interplay between place and product categories can shape consumer attitudes.The results of a series of psychometric tests suggest that association strength and the interplay between place and product category constitute antecedent conditions that are crucial for determining if a country-of-origin effect will occur. These findings, and their implications for future research as well as for practice, suggest that a reevaluation of the country-of-origin effect with a widening of the scope to encompass the commercial relevance of place writ large is warranted.
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| 14. |
- Andersson, C. David, et al.
(författare)
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Benefits of statistical molecular design, covariance analysis, and reference models in QSAR : a case study on acetylcholinesterase
- 2015
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Ingår i: Journal of Computer-Aided Molecular Design. - : Springer Science and Business Media LLC. - 0920-654X .- 1573-4951. ; 29:3, s. 199-215
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Tidskriftsartikel (refereegranskat)abstract
- Scientific disciplines such as medicinal- and environmental chemistry, pharmacology, and toxicology deal with the questions related to the effects small organic compounds exhort on biological targets and the compounds' physicochemical properties responsible for these effects. A common strategy in this endeavor is to establish structure-activity relationships (SARs). The aim of this work was to illustrate benefits of performing a statistical molecular design (SMD) and proper statistical analysis of the molecules' properties before SAR and quantitative structure-activity relationship (QSAR) analysis. Our SMD followed by synthesis yielded a set of inhibitors of the enzyme acetylcholinesterase (AChE) that had very few inherent dependencies between the substructures in the molecules. If such dependencies exist, they cause severe errors in SAR interpretation and predictions by QSAR-models, and leave a set of molecules less suitable for future decision-making. In our study, SAR- and QSAR models could show which molecular sub-structures and physicochemical features that were advantageous for the AChE inhibition. Finally, the QSAR model was used for the prediction of the inhibition of AChE by an external prediction set of molecules. The accuracy of these predictions was asserted by statistical significance tests and by comparisons to simple but relevant reference models.
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| 15. |
- Andersson, Gerhard, et al.
(författare)
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Free choice of treatment content, support on demand and supervision in internet-delivered CBT for adults with depression : A randomized factorial design trial
- 2023
-
Ingår i: Behaviour Research and Therapy. - : Elsevier. - 0005-7967 .- 1873-622X. ; 162
-
Tidskriftsartikel (refereegranskat)abstract
- Even if much is known regarding the effects of internet-delivered cognitive behaviour therapy (ICBT) for depression there are several topics that have not been studied. In this factorial design trial with 197 participants we investigated if clients in ICBT could select treatment modules themselves based on a selection of 15 tailored treatment modules developed for use in ICBT for depression. We contrasted this against clinician-tailored module selection. We also investigated if support on demand (initiated by the client) could work as well as scheduled support. Finally, we tested if clients that were mentioned in supervision would improve more than clients not mentioned (with the exception of acute cases). The treatment period lasted for 10 weeks, and we measured effects at post-treatment and two-year follow-up. Measures of depression and secondary outcomes were collected at pre-treatment, post-treatment and two-year follow-up. Overall, within-group effects were large across con-ditions (e.g., d = 1.73 on the BDI-II). We also found a small but significant difference in favour of self-tailored treatment over clinician-tailored (d = 0.26). Within-group effects for the secondary measures were all moderate to large including a test of knowledge about CBT. The other two contrasts "support on demand" and "supervision" yielded mostly non-significant differences, with the exception of a larger dropout rate in the support on demand condition. There were few negative effects (2.2%). Effects were largely maintained at a two-year follow-up. We conclude that clients can choose treatment modules and that support on demand may work. The role of su-pervision is not yet clear as advice can be transferred across clients.
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| 16. |
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| 17. |
- Badam, Tejaswi, et al.
(författare)
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CD4(+) T-cell DNA methylation changes during pregnancy significantly correlate with disease-associated methylation changes in autoimmune diseases
- 2022
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Ingår i: Epigenetics. - : Taylor & Francis Group. - 1559-2294 .- 1559-2308. ; 17:9, s. 1040-1055
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Tidskriftsartikel (refereegranskat)abstract
- Epigenetics may play a central, yet unexplored, role in the profound changes that the maternal immune system undergoes during pregnancy and could be involved in the pregnancy-induced modulation of several autoimmune diseases. We investigated changes in the methylome in isolated circulating CD4(+) T-cells in non-pregnant and pregnant women, during the 1(st) and 2(nd) trimester, using the Illumina Infinium Human Methylation 450K array, and explored how these changes were related to autoimmune diseases that are known to be affected during pregnancy. Pregnancy was associated with several hundreds of methylation differences, particularly during the 2(nd) trimester. A network-based modular approach identified several genes, e.g., CD28, FYN, VAV1 and pathways related to T-cell signalling and activation, highlighting T-cell regulation as a central component of the observed methylation alterations. The identified pregnancy module was significantly enriched for disease-associated methylation changes related to multiple sclerosis, rheumatoid arthritis and systemic lupus erythematosus. A negative correlation between pregnancy-associated methylation changes and disease-associated changes was found for multiple sclerosis and rheumatoid arthritis, diseases that are known to improve during pregnancy whereas a positive correlation was found for systemic lupus erythematosus, a disease that instead worsens during pregnancy. Thus, the directionality of the observed changes is in line with the previously observed effect of pregnancy on disease activity. Our systems medicine approach supports the importance of the methylome in immune regulation of T-cells during pregnancy. Our findings highlight the relevance of using pregnancy as a model for understanding and identifying disease-related mechanisms involved in the modulation of autoimmune diseases.
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| 18. |
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| 19. |
- Bálint, Adám, et al.
(författare)
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The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant
- 2009
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Ingår i: Virology Journal. - 1743-422X. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA) of the human-like H1N2 SIV viruses and the neuraminidase (NA) of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain.The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.
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| 20. |
- Belak, Sandor, et al.
(författare)
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New viruses in veterinary medicine, detected by metagenomic approaches
- 2013
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Ingår i: Veterinary Microbiology. - : Elsevier BV. - 0378-1135 .- 1873-2542. ; 165, s. 95-101
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Tidskriftsartikel (refereegranskat)abstract
- In our world, which is faced today with exceptional environmental changes and dramatically intensifying globalisation, we are encountering challenges due to many new factors, including the emergence or re-emergence of novel, so far “unknown” infectious diseases. Although a broad arsenal of diagnostic methods is at our disposal, the majority of the conventional diagnostic tests is highly virus-specific or is targeted entirely towards a limited group of infectious agents. This specificity complicates or even hinders the detection of new or unexpected pathogens, such as new, emerging or re-emerging viruses or novel viral variants. The recently developed approaches of viral metagenomics provide an effective novel way to screen samples and detect viruses without previous knowledge of the infectious agent, thereby enabling a better diagnosis and disease control, in line with the “One World, One Health” principles (www.oneworldonehealth.org). Using metagenomic approaches, we have recently identified a broad variety of new viruses, such as novel bocaviruses, Torque Teno viruses, astroviruses, rotaviruses and kobuviruses in porcine disease syndromes, new virus variants in honeybee populations, as well as a range of other infectious agents in further host species. These findings indicate that the metagenomic detection of viral pathogens is becoming now a powerful, cultivation-independent, and useful novel diagnostic tool in veterinary diagnostic virology.
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| 21. |
- Berenjian, Saideh, 1963-
(författare)
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Construction of Adenovirus Vectors for Studies of Protein Function and RNA Interference
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- During an adenovirus infection the accumulation of alternatively spliced mRNAs is subjected to a tight temporal regulation. The IIIa protein is a structural protein expressed exclusively late after infection. To study the significance of the restricted IIIa protein expression we used a Tet-ON regulated adenoviral vector to overexpress the IIIa protein during the early phase of infection. The results show that unregulated IIIa protein expression caused a reduction in late viral protein accumulation and a slight block of viral DNA replication. Further, the results indicate that IIIa splicing might be subjected to a regulation via a feed back loop stimulating its own expression. To improve the efficacy of vectors for regulated transgene expression, we constructed binary adenoviral vectors based on the Tet-ON and Tet-OFF systems. These vectors encode both the transcriptional activator and the tetracycline-regulated expression cassette from the same viral unit, ensuring that each infected cell will express both the activator and the reporter gene. In model experiments this system was shown to result in a tight control of gene expression with no detectable background expression of the transgene and induction levels reaching 500-600 fold. Introduction of dsRNA into a cell will induce a sequence specific degradation of the homologous mRNA via a mechanism named RNA interference (RNAi). The adenovirus VA RNAs are short highly structured RNAs that are expressed in large amounts late during an adenovirus infection. Here we showed that both VA RNAI and VA RNAII functions as virus-encoded suppressors of RNAi, by interfering with the activity of Dicer, the enzyme that cleaves the initial dsRNA to short-interfering RNAs (siRNAs) that mediate RNAi. Further, the VA RNAs themselves are substrates for Dicer and are cleaved into siRNAs in vivo that are incorporated into active RNA-induced silencing complexes. There is a great interest in developing novel therapeutic strategies based on RNAi. We constructed adenoviral vectors that express short hairpin RNAs, which in vivo will be cleaved to siRNAs that induce sequence-specific RNAi. We compared the efficiency of RNAi induced by vectors based on the viral VA RNAI and the human U6 promoters. Our results suggest that under conditions where the recombinant virus does not replicate, the VA RNA promoter is more effective in down regulating target gene expression, whereas the U6 promoter was more effective under replicative conditions.
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| 22. |
- Berg, Björn, et al.
(författare)
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Decomposition rates in late stages of Scots pine and Norway spruce needle litter: Influence of nutrients and substrate properties over a climate gradient
- 2022
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Ingår i: Forest Ecology and Management. - : Elsevier. - 0378-1127 .- 1872-7042. ; 522
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this paper is to show different patterns for decomposition of the main mass of needle litter from two boreal and temperate coniferous tree species, both leading to a stabilized fraction of litter. To this purpose we have reviewed information on decomposition patterns in the lignin-dominated (late) stages of two local foliar litter types, namely those of Scots pine (Pinus silvestris) and Norway spruce (Picea abies) from two climatic gradients of equal extension. We have also reviewed factors determining the limit values for both species.Long-term decomposition studies were used to calculate annual mass loss in the lignin-dominated decomposition stage and relate these to mean annual temperature (MAT), mean annual precipitation (MAP) and concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn) and acid unhydrolyzable residue (gravimetric lignin, AUR).There was no effect of MAT on decomposition of either needle litter type. MAP had a rate-dampening effect on decomposition of Norway spruce litter. There was a rate-stimulating effect of Mn for Norway spruce litter but not for that of Scots pine. In spite of the strong negative effect of AUR and N on decomposition of Scots pine litter there was none at all for that of Norway spruce.Limit values for decomposition were related to the litters’ initial concentrations of N, Mn and AUR and differed between litter types for locally collected, natural litter and for that from experimental litter, the latter having higher N and lower Mn concentrations than the natural litter.We conclude that the two litter types have clear differences as regards rate- regulating factors for decomposition in the late lignin-dominated stage as well as for the stable fraction and suggest two different pathways for their decomposition. This is the first time that different pathways have been suggested for decomposing litter.
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| 23. |
- Berg, Björn, et al.
(författare)
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Long-term effects of climate and litter chemistry on rates and stable fractions of decomposing Scots pine and Norway spruce needle litter - A synthesis
- 2022
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Ingår i: Forests. - : MDPI. - 1999-4907. ; 13:1
-
Tidskriftsartikel (refereegranskat)abstract
- We have reviewed information on early-, late- and limit-value decomposition stages for litter of Norway spruce (Picea abies) and Scots pine (Pinus silvestris). This synthesis covers c 16 studies/papers made along a climatic gradient; range in mean annual temperature (MAT) from −1 to +7 °C and mean annual precipitation (MAP) from 425 to 1070 mm. Scots pine has an early stage dominated by carbohydrate decomposition and a late stage dominated by decomposition of lignin; Norway spruce has just one stage dominated by lignin decomposition. We used data for annual mass loss to identify rate-regulating factors in both stages; climate data, namely, MAT and MAP, as well as substrate properties, namely, nitrogen (N), acid unhydrolyzable residue (AUR), manganese (Mn). Early-stage decomposition for Scots pine litter was dominated positively by MAT; the late stage was dominated negatively by MAT, N, and AUR, changing with decomposition stage; there was no effect of Mn. Norway spruce litter had no early stage; decomposition in the lignin-dominated stage was mainly negative to MAP, a negative relationship to AUR and non-significant relationships to N and MAT. Mn had a positive relationship. Limit values for decomposition, namely, the accumulated mass loss at which decomposition is calculated to be zero, were related positively to Mn and AUR for Scots pine litter and negatively to AUR for Norway spruce litter. With different sets of rate-regulating factors as well as different compounds/elements related to the limit values, the decomposition patterns or pathways are different.
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| 24. |
- Berg, Björn, 1943-, et al.
(författare)
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Magnesium dynamics in decomposing foliar litter - a synthesis
- 2021
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Ingår i: Geoderma. - : Elsevier. - 0016-7061 .- 1872-6259. ; 382
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Tidskriftsartikel (refereegranskat)abstract
- We synthesized available data for magnesium (Mg) dynamics in newly shed and decomposing foliar litter of mainly pine (Pinus) species, Norway spruce (Picea abies), and birch (Betula) species. Using original, measured data from 40 stands organized in climatic gradients we intended to determine patterns of Mg concentration and net release vs accumulated mass loss of the litter. This synthesis is likely the first synthesis of Mg dynamics in decomposing litter.In paired stands, litter of both Norway spruce and lodgepole pine (Pinus contorta) had higher Mg concentrations than Scots pine (Pinus silvestris), with concentrations in Norway spruce litter even twice as high.In decomposing litter, Mg concentrations followed a quadratic (X2-X) function vs accumulated mass loss and consequently had minima, different for Norway spruce and Scots pine litter. Out of 68 decomposition studies 53 gave minimum concentration. The Mg minimum concentration during decomposition was positively related to initial Mg concentration for Scots pine and Scots pine plus lodgepole pine but not for Norway spruce. The increase in concentration suggests that after the minimum Mg was temporarily limiting.For Norway spruce litter there was a relationship between minimum concentration of Mg and the limit value. There was no such relationship for Scots pine and not for the combined pine data.Magnesium net release started directly after the incubation and was linear to accumulated mass loss of litter, giving a slope coefficient (release rate) for each study. The net release rate was linear to initial Mg concentration and all studies combined gave a negative linear relationship.
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| 25. |
- Berg, Frenk van den, et al.
(författare)
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How the EU project “Online Microstructure Analytics” advances inline sensing of microstructure during steel manufacturing
- 2023
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Ingår i: Research and Review Journal of Nondestructive Testing (ReJNDT). - Lisabon : NDT.net GmbH & Co. KG. - 2941-4989. ; 1:1
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Tidskriftsartikel (refereegranskat)abstract
- Weight savings in mobility and transport are mandatory in order to reduce CO2 emissions and energy consumption. The steel industry offers weight saving solutions by a growing portfolio of Advanced High Strength Steel (AHSS) products. AHSS owe their strength to their largely refined and complex microstructures, containing multiple metallurgical phases. Optimal control of the thermo-mechanical processing of AHSS requires inline sensors for real-time monitoring of evolution and consistency of microstructure and material properties.
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