| 1. |
- Dezfouli, Mahya, et al.
(author)
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Newborn Screening for Presymptomatic Diagnosis of Complement and Phagocyte Deficiencies
- 2020
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In: Frontiers in Immunology. - : FRONTIERS MEDIA SA. - 1664-3224. ; 11
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Journal article (peer-reviewed)abstract
- The clinical outcomes of primary immunodeficiencies (PIDs) are greatly improved by accurate diagnosis early in life. However, it is not common to consider PIDs before the manifestation of severe clinical symptoms. Including PIDs in the nation-wide newborn screening programs will potentially improve survival and provide better disease management and preventive care in PID patients. This calls for the detection of disease biomarkers in blood and the use of dried blood spot samples, which is a part of routine newborn screening programs worldwide. Here, we developed a newborn screening method based on multiplex protein profiling for parallel diagnosis of 22 innate immunodeficiencies affecting the complement system and respiratory burst function in phagocytosis. The proposed method uses a small fraction of eluted blood from dried blood spots and is applicable for population-scale performance. The diagnosis method is validated through a retrospective screening of immunodeficient patient samples. This diagnostic approach can pave the way for an earlier, more comprehensive and accurate diagnosis of complement and phagocytic disorders, which ultimately lead to a healthy and active life for the PID patients.
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| 2. |
- Ahlberg, Erik, et al.
(author)
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"Vi klimatforskare stödjer Greta och skolungdomarna"
- 2019
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In: Dagens nyheter (DN debatt). - 1101-2447.
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Journal article (pop. science, debate, etc.)abstract
- DN DEBATT 15/3. Sedan industrialiseringens början har vi använt omkring fyra femtedelar av den mängd fossilt kol som får förbrännas för att vi ska klara Parisavtalet. Vi har bara en femtedel kvar och det är bråttom att kraftigt reducera utsläppen. Det har Greta Thunberg och de strejkande ungdomarna förstått. Därför stödjer vi deras krav, skriver 270 klimatforskare.
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| 3. |
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| 4. |
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| 5. |
- Bye, E., et al.
(author)
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Quantitative Determination of Airborne Respirable Non-Fibrous alpha-Silicon Carbide by X-ray Powder Diffractometry
- 2009
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In: Annals of Occupational Hygiene. - : Oxford University Press (OUP). - 0003-4878 .- 1475-3162. ; 53:4, s. 403-408
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Journal article (peer-reviewed)abstract
- Objectives: The purpose of the present investigation was to establish a method for the determination of airborne respirable non-fibrous silicon carbide (SiC). The main application is within the industrial production of SiC. Methods: Due to the complex airborne aerosol mixture of crystalline compounds in the SiC industry, X-ray powder diffractometry was selected as the most appropriate method. Without any international standard material for the respirable fraction of non-fibrous SiC, pure and suitable products from three SiC plants in Norway were selected. These products have a median particle diameter in the range 4.4-5.1 mu m. The method is based on thin sample technique, with the dust deposited on a polycarbonate filter. Absorption correction is done by standard procedures with the use of a silver filter, situated below the polycarbonate filter. Results: The diffraction line used for quantitative determination was selected carefully. This was done to avoid interferences from quartz, cristobalite, and graphite, which all are airborne components present in the atmosphere during the industrial process. The instrumental limit of detection for the method is 12 mu g. Conclusions: This method has been used to determine airborne non-fibrous SiC in a comprehensive ongoing project in the Norwegian SiC industry for further epidemiological studies. The method is fully applicable for compliance work.
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| 6. |
- Carlsson, Lennart, 1970-
(author)
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Aspects of interferon alpha signalling in hematopoetic cells
- 2004
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Doctoral thesis (other academic/artistic)abstract
- The type I interferons (IFN) are a family of cytokines with pleiothropic activities that include inhibition of viral replication, cell proliferation and activation of the immune system. These properties give the IFNs important physiological and pathological roles in infection and cancer and have led to their therapeutic use for many clinical conditions. In humans, the type I IFNs consist of 12 different IFNa subtypes as well as single IFNb, w and k subtypes. They all compete for binding to a common receptor, consisting of two subunits, IFNAR1 and IFNAR2. In almost all cell types proliferation is inhibited by IFNs as a consequence of the antiviral properties. However, previous studies on human peripheral B-lymphocytes have shown increased survival as well as proliferation upon IFN treatment.We established a purification system for extraction of B-lymphocytes from buffy-coat, utilizing density centrifugation in combination with anti-CD19 magnetic beads. In an attempt to identify the molecular mechanisms of increased survival, the expression and/or activation pattern of different signaling proteins were analysed by Western blot. It was previously reported that phosphatidylinositol 3’-kinase (PI3K) physically interacts with the IFNAR complex, via adaptor proteins. Activated PI3K indirectly activates Akt/PKB, a kinase involved in a pathway leading to both survival and proliferation signals. We were able to show a novel signaling pathway - IFN treatment activated Akt/PKB as well as a downstream effector, one member of the Forkhead family (FKHR) was inactivated by phosphorylation and as a consequence p27/Kip1 expression was downregulated. Activation of this pathway resulted in increased survival as measured by TUNEL assay, an effect efficiently counteracted by the the synthetic PI3K inhibitor, LY294002.In additional experiments we investigated the molecular mechanisms of proliferation. Activation of B-cells was ensured by using limiting concentrations of anti-IgM antibodies, mimicing natural activation. Using thymidine incorporation, we discovered that IFN treatment increased the sensitivity to anti-IgM stimulation. As a consequence, more cells proliferated as measured by CFSE staining. However, on its own, IFN was unable to induce proliferation. IFN turned out to be as efficient as IL-2, a classical B-lymphocyte growth factor. In order to distinguish proliferation from increased survival, Rb phoshorylation was analysed by Western blot. Phosphorylation induced by anti-IgM was further enhanced by IFN. As we determined earlier, p27/Kip1 expression was downregulated, releasing the cell cycle block. However, p21/Cip1 expression was upregulated but almost exclusively localised to the cytoplasm, therefore unable to perform the classical growth inhibitory functions. We conclude that type I interferons contribute to increased survival as well as proliferation of human primary B-lymphocytes.The IFN receptor subunits was studied in a human myeloma cell line (U266), using a variant of which that are totally resistant towards the anti-proliferative properties of IFN. The reason for resistance in clinical situations is seldom elucidated, but is often believed to be due to development of antibodies against interferon. The resistant cells were unable to bind radio-labelled IFN, and through Southern Blot we could determine that the IFNAR1 gene was not functional. Also the IFNAR2 gene was affected, since Northern blot and sequencing detected an aberrant transcript not present in the wild type cells. Karyotyping showed that the cells had 3-4 copies of chromosome 21, but Southern blot did not detect any cytoplasmic region of IFNAR2. The IFN receptors are close to each other on the genome, and a deletion affecting one receptor gene is likely to affect the other as well. We conclude that the IFN resistance in U266Res cells is due to lack of functional receptor subunits.
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| 7. |
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| 8. |
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| 9. |
- Elfgren, Lennart, et al.
(author)
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Guideline for application of new technologies to extend life of elderly rail infrastructure : Deliverable 1.4 in MAINLINE - a project within EC 7tf Framework Programme
- 2015
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Reports (pop. science, debate, etc.)abstract
- There are many traditional technologies available to extend the life of elderly rail infrastructure, some of which are being improved or developed, whilst new technologiescontinue to emerge. In this guideline some of the most promising new or updated technologies are presented forbridges, track and earthwork regarding: - Assessment methods- Repair and Strengthening methodsIn an Appendix strengthening methods are presented in more detail with examples of designcalculations and work carried out.The guideline is based on work presented in earlier reports in MAINLINE: ML-D1.1 (2013):Benchmark of new technologies to extend the life of elderly rail infrastructure, ML-D1.2(2013): Assessment methods for elderly rail infrastructure and ML-D1.3 (2014): Newtechnologies to extend the life of elderly infrastructure; In these reports, backgroundinformation and more references can also be found.
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| 10. |
- Elfgren, Lennart, et al.
(author)
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New technologies to extend the life of elderly rail infrastructure : Deliverable 1.3 in MAINLINE - a project within the EC 7th Framework Programme
- 2015
-
Reports (peer-reviewed)abstract
- There are many traditional technologies available to extend the life of elderly rail infrastructure, some of which are being improved or developed, whilst new technologies continue to emerge.In two earlier reports a benchmark of new technologies was given and assessment methods were presented, ML-D1.1 (2013) and ML-D1.2 (2013). In this report, ML-D1.3, an overview is given of some of the most promising new or updated technologies. Based on the findings, work in the Mainline project has focused on the following two areas for bridges, tunnels and track:- Assessment methods- Repair and Strengthening methodsSome of the methods are still under development and may not yet be available commercially. Hence these are presented on a “for information” basis and as something that may be introduced on a broader scale in a near future.In the report assessment and strengthening of bridges are treated in Chapter 4 and Chapter 5.Tunnels are treated in Chapter 6 and track and earthwork in Chapter 7.The report also includes with five appendices with details of important work that has been donein the MAINLINE project. Appendix A presents results from the assessment and full scale testing to failure of a 50 year old metallic truss bridge. Appendix B presents results from the strengthening by post-tensioning of a concrete trough bridge. Appendix C presents methods to extend life for tunnels. Appendix D proposes methods for the assessment of fatigue andAppendix E, finally, gives a fairly comprehensive list of references on how to extend the life of structures.A Guideline for application of the new technologies is given in ML-D1.4 (2014).
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| 11. |
- Elfström, Magnus, 1971-, et al.
(author)
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Temperamental and behavioural characteristics of adults seeking treatment for severe dental fear
- 2009
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In: Psychology and Health. - : Informa UK Limited. - 0887-0446 .- 1476-8321. ; 24:sup. 1, s. 162-
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Journal article (other academic/artistic)abstract
- Other psychological/behavioral factors in addition to fear and traditional measures of psychopathology should possibly be considered in the assessment and treatment of dental fear. The present study investigated fear and personality profiles among severely fearful adult patients. Participants were 230 consecutive adults applying for treatment of severe dental anxiety at a specialized clinic. Background data included dental treatment and dental fear history, general anxiety and depression assessments. Cluster analyses were performed. Four different fear and personality subgroups were judged to best represent data: (I) Fearful, extrovert, outgoing, (II) Highly fearful, extrovert, outgoing, (III) Fearful, inhibited, and (IV) Highly fearful, multiple problems. The view that adults with dental fear comprise a heterogeneous group was strengthened. Apart from different levels of dental fear, there seems to be varying temperamental and behavioral characteristics that need to be further studied and that may lead to a better match of treatment for these patients.
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| 12. |
- Fatemi, Maryam, 1982, et al.
(author)
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Variational Bayesian EM for SLAM
- 2015
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In: IEEE 6th International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP), 2015, Cancun, Mexico, 13-16 Dec. 2015. - 9781479919635 ; , s. 501-504
-
Conference paper (peer-reviewed)abstract
- Designing accurate, robust and cost-effective systems is an important aspect of the research on self-driving vehicles. Radar is a common part of many existing automotive solutions and it is robust to adverse weather and lighting conditions, as such it can play an important role in the design of a self-driving vehicle. In this paper, a radar-based simultaneous localization and mapping (SLAM) algorithm using variational Bayesian expectation maximization (VBEM) is presented. The VBEM translates the inference problem to an optimization one. It provides an efficient and powerful method to estimate the unknown data association variables as well as the map of the environment as perceived by a radar and the unknown trajectory of the vehicle.
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| 13. |
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| 14. |
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| 15. |
- Fobelets, Kristel, et al.
(author)
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High-frequency capacitance of bipolar resonant tunneling diodes
- 1996
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In: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 79:2, s. 905-910
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Journal article (peer-reviewed)abstract
- The high-frequency characteristics of bipolar resonant tunneling diodes are experimentally investigated at room temperature. The electron accumulation and discharging in these resonant tunneling light-emitting diodes are studied at frequencies up to 35 GHz. The experiments show capacitance peaks due to electron charge disappearing from the quantum well. The measurements are found to be in agreement with our theoretical model for the calculation of the high-frequency characteristics of resonant tunneling devices. The high-frequency characteristics of the bipolar light-emitting resonant tunneling diode are compared to the unipolar resonant tunneling diode and the resonant interband tunneling diode. The comparison shows a similar discharging characteristic of the quantum well, but a different overall variation of the capacitance.
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| 16. |
- Frändberg, Emma, et al.
(author)
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Streptomyces halstedii K122 produces the antifungal compounds bafilomycin B1 and C1
- 2000
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In: Canadian journal of microbiology (Print). - : NRC Research Press. - 0008-4166 .- 1480-3275. ; 46:8, s. 753-758
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Journal article (peer-reviewed)abstract
- Streptomyces halstedii K122 was previously found to produce antifungal compounds on solid substrates that inhibit radial growth of fungi among Ascomycetes, Basidiomycetes, Deuteromycetes, Oomycetes, and Zygomycetes, and strongly affected hyphal branching and morphology. During growth of S. halstedii K122 in submerged culture, no antifungal activity could be detected. However, cultivation of S. halstedii in thin (1 mm) liquid substrate layers in large surface-area tissue culture flasks caused intense growth and sporulation of S. halstedii K122, and the biologically active compounds could be extracted from the mycelium with methanol. Antifungal compounds were purified using C18 solid phase extraction and silica gel column chromatography, and identified as bafilomycins B1 and C1, using 2D NMR and FAB MS. Production of bafilomycins, which are specific inhibitors of vacuolar ATPases, has not been reported from S. halstedii previously. Minimum inhibitory concentrations (MIC) of bafilomycins BI and C1, amphotericin B, and nikkomycin Z were determined at pH 5.5 and 7.0 for the target fungi Aspergillus fumigatus, Mucor hiemalis, Penicillium roqueforti, and Paecilomyces variotii. Penicillium roqueforti was the most sensitive species to all the compounds investigated. The MIC values for amphotericin B were 0.5-4 mu g.mL(-1) for the fungi tested, and pH did not affect the toxicity. The MIC values for nikkomycin Z ranged from <0.5 mu g.mL(-1) for Mucor hiemalis to >500 mu g.mL(-1) for Aspergillus fumigatus, and pH had no influence on toxicity. Bafilomycins B1 and C1 were equally active against the fungal species tested, with MIC values in the range of <0.5-64 mu g.mL(-1). All fungi were more sensitive to both bafilomycin B1 and C1 at pH 7.0 than at pH 5.5.
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| 17. |
- Gautam, Narinder, et al.
(author)
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Heparin-binding protein (HBP/CAP37): A missing link in neutrophil-evoked alteration of vascular permeability
- 2001
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In: Nature Medicine. - : Springer Science and Business Media LLC. - 1546-170X .- 1078-8956. ; 7:10, s. 1123-1127
-
Journal article (peer-reviewed)abstract
- Polymorphonuclear leukocyte infiltration into tissues in host defense and inflammatory diseasecauses increased vascular permeability and edema formation through unknown mechanisms.Here, we report the involvement of a paracrine mechanism in neutrophil-evoked alteration inendothelial barrier function. We show that upon neutrophil adhesion to the endothelial lining,leukocytic 2 integrin signaling triggers the release of neutrophil-borne heparin-binding protein(HBP), also known as CAP37/azurocidin, a member of the serprocidin family of neutrophilcationic proteins. HBP induced Ca++-dependent cytoskeletal rearrangement and intercellular gapformation in endothelial-cell monolayers in vitro, and increased macromolecular efflux in microvesselsin vivo. Moreover, selective inactivation of HBP prevented the neutrophils from inducingendothelial hyperpermeability. Our data suggest a fundamental role of neutrophil-derivedHBP in the vascular response to neutrophil trafficking in inflammation. Targeting this moleculein inflammatory disease conditions offers a new strategy for prevention of endothelial barrierdysfunction caused by misdirected leukocyte activation.
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| 18. |
- Hagbom, Marie, 1971-
(author)
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Rotavirus Disease Mechanisms Diarrhea, Vomiting and Inflammation : How and Why
- 2015
-
Doctoral thesis (other academic/artistic)abstract
- Rotavirus infections cause diarrhea and vomiting that can lead to severe dehydration. Despite extensive tissue damage and cell death, the inflammatory response is very limited. The focus of this thesis was to study pathophysiological mechanisms behind diarrhea and vomiting during rotavirus infection and also to investigate the mechanism behind the limited inflammatory response.An important discovery in this thesis was that rotavirus infection and the rotavirus toxin NSP4 stimulate release of the neurotransmitter serotonin from intestinal sensory enterochromaffin cells, in vitro and ex vivo. Interestingly, serotonin is known to be a mediator of both diarrhea and vomiting. Moreover, mice pups infected with rotavirus responded with central nervous system (CNS) activation in brain structures associated with vomiting, thus indicating a cross-talk between the gut and brain in rotavirus disease.Our finding that rotavirus infection activates the CNS led us to address the hypothesis that rotavirus infection not only activates the vagus nerve to stimulate vomiting, but also suppresses the inflammatory response via the cholinergic anti-inflammatory pathway, both of which are mediated by activated vagal afferent nerve signals into the brain stem. We found that mice lacking an intact vagus nerve, and mice lacking the α7 nicotine acetylcholine receptor (nAChR), being involved in cytokine suppression from macrophages, responded with a higher inflammatory response.Moreover, stimulated cytokine release from macrophages, by the rotavirus toxin NSP4, could be attenuated by nicotine, an agonist of the α7 nAChR. Thus, it seems most reasonable that the cholinergic anti-inflammatory pathway contributes to the limited inflammatory response during rotavirus infection. Moreover, rotavirus-infected mice displayed increased intestinal motility at the onset of diarrhea, which was not associated with increased intestinal permeability. The increased motility and diarrhea in infant mice could be attenuated by drugs acting on the enteric nervous system, indicating the importance and contribution of nerves in the rotavirus mediated disease.In conclusion, this thesis provides further insight into the pathophysiology of diarrhea and describe for the first time how rotavirus and host cross-talk to induce the vomiting reflex and limit inflammation. Results from these studies strongly support our hypothesis that serotonin and activation of the enteric nervous system and CNS contributes to diarrhea, vomiting and suppression of the inflammatory response in rotavirus disease.
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| 19. |
- Hagbom, Marie, et al.
(author)
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Rotavirus Stimulates Release of Serotonin (5-HT) from Human Enterochromaffin Cells and Activates Brain Structures Involved in Nausea and Vomiting
- 2011
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In: PLOS PATHOGENS. - : Public Library of Science (PLoS). - 1553-7366 .- 1553-7374. ; 7:7
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Journal article (peer-reviewed)abstract
- otavirus (RV) is the major cause of severe gastroenteritis in young children. A virus-encoded enterotoxin, NSP4 is proposed to play a major role in causing RV diarrhoea but how RV can induce emesis, a hallmark of the illness, remains unresolved. In this study we have addressed the hypothesis that RV-induced secretion of serotonin (5-hydroxytryptamine, 5-HT) by enterochromaffin (EC) cells plays a key role in the emetic reflex during RV infection resulting in activation of vagal afferent nerves connected to nucleus of the solitary tract (NTS) and area postrema in the brain stem, structures associated with nausea and vomiting. Our experiments revealed that RV can infect and replicate in human EC tumor cells ex vivo and in vitro and are localized to both EC cells and infected enterocytes in the close vicinity of EC cells in the jejunum of infected mice. Purified NSP4, but not purified virus particles, evoked release of 5-HT within 60 minutes and increased the intracellular Ca(2+) concentration in a human midgut carcinoid EC cell line (GOT1) and ex vivo in human primary carcinoid EC cells concomitant with the release of 5-HT. Furthermore, NSP4 stimulated a modest production of inositol 1,4,5-triphosphate (IP(3)), but not of cAMP. RV infection in mice induced Fos expression in the NTS, as seen in animals which vomit after administration of chemotherapeutic drugs. The demonstration that RV can stimulate EC cells leads us to propose that RV disease includes participation of 5-HT, EC cells, the enteric nervous system and activation of vagal afferent nerves to brain structures associated with nausea and vomiting. This hypothesis is supported by treating vomiting in children with acute gastroenteritis with 5-HT(3) receptor antagonists.
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| 20. |
- Hagbom, Marie, et al.
(author)
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Towards a human rotavirus disease model
- 2012
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In: Current Opinion in Virology. - : Elsevier BV. - 1879-6257. ; 2:4, s. 408-418
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Journal article (peer-reviewed)abstract
- While the clinical importance of human rotavirus (RV) disease is well recognized and potent vaccines have been developed, our understanding of how human RV causes diarrhoea, vomiting and death remains unresolved. The fact that oral rehydration corrects electrolyte and water loss, indicates that enterocytes in the small intestine have a functional sodium-glucose co-transporter. Moreover, RV infection delays gastric emptying and loperamide appears to attenuate RV diarrhoea, thereby suggesting activation of the enteric nervous system. Serotonin (5-HT) receptor antagonists attenuate vomiting in young children with gastroenteritis while zinc and enkephalinase inhibitors attenuate RV-induced diarrhoea. In this review we discuss clinical symptoms, pathology, histology and treatment practices for human RV infections and compile the data into a simplified disease model.
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| 21. |
- Hamann, Dathan, et al.
(author)
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Jewellery : alloy composition and release of nickel, cobalt and lead assessed with the EU synthetic sweat method
- 2015
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In: Contact Dermatitis. - : Wiley. - 0105-1873 .- 1600-0536. ; 73:4, s. 231-238
-
Journal article (peer-reviewed)abstract
- Background. Several studies have shown nickel and cobalt release from jewellery by using spot tests, but the metal composition of jewellery is largely unknown. Objectives. To evaluate the metal composition of a large worldwide sample of mainly inexpensive jewellery items, and investigate the release of nickel, cobalt and lead from a subsample by using EN 1811: 1998-required methods. Methods. A total of 956 metallic jewellery components were examined with X-ray fluorescence spectroscopy. A subsample of 96 jewellery items purchased in the United States were investigated for nickel, cobalt and lead release by the use of artificial sweat immersion and plasma optical emission spectroscopy. Results. Eighteen elements were detected. The 10 most frequently occurring were, in order of frequency, copper, iron, zinc, nickel, silver, chromium, tin, manganese, lead, and cobalt. Release of nickelwas noted from 79 of the 96 US samples (0.01-98 mu g/cm(2)/week), release of cobalt from 35 samples (0.02-0.5 mu g/cm(2)/week), and release of lead from 37 samples (0.03-2718 mu g/cm(2)/week). Conclusions. We present here a comprehensive list of the most frequently encountered metals in jewellery and fashion accessories. Different allergenic and non-allergenic metals are utilized. We also report the frequent release of nickel, cobalt and lead from these objects, despite legislative restrictions.
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| 22. |
- Hammarstrand, Lars, 1979, et al.
(author)
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Adaptive Radar Sensor Model for Tracking Structured Extended Objects
- 2012
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In: IEEE Transactions on Aerospace and Electronic Systems. - 1557-9603 .- 0018-9251. ; 48:3, s. 1975 - 1995
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Journal article (peer-reviewed)abstract
- We propose a tracking framework jointly estimating the position of a single extended object and the set of radar reflectors that it contains. The reflectors are assumed to lie on a line structure, but the number of reflectors and their positions on the line are unknown. Additionally, we incorporate an accurate radar sensor model considering the resolution capabilities of the sensor. The evaluation of the framework on radar measurements shows promising results.
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| 23. |
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| 24. |
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| 25. |
- Jakobsen, Stig S., et al.
(author)
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Failure of total hip implants : metals and metal release in 52 cases
- 2014
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In: Contact Dermatitis. - : Wiley. - 0105-1873 .- 1600-0536. ; 71:6, s. 319-325
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Journal article (peer-reviewed)abstract
- BackgroundThe pathogenesis of total joint replacement failure is multifactorial. One hypothesis suggests that corrosion and wear of alloys result in metal ion release, which may then cause sensitization and even implant failure, owing to the acquired immune reactivity. ObjectivesTo assess cobalt, nickel and chromium(VI) release from, and the metal composition of, failed metal-on-ethylene total hip replacements. Materials/methodsImplant components from 52 revision cases were evaluated with spot tests for free nickel, cobalt, and chromium (VI) ions. Implant composition was determined with X-ray fluorescence spectroscopy, and information on the reason for revision and complications in relation to surgery was collected from the medical charts when possible (72%). For 10 implants, corrosion was further characterized with scanning electron microscopy. ResultsWe detected cobalt release from three of 38 removed femoral heads and from one of 24 femoral stems. Nickel release was detected from one of 24 femoral stems. No chromium(VI) release was detected. ConclusionsWe found that cobalt and nickel were released from some failed total hip arthroplasties, and corrosion was frequently observed. Metal ions and particles corroded from metal-on-polyethylene may play a role in the complex aetiopathology of implant failure.
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| 26. |
- Julander, Anneli, et al.
(author)
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Formal recycling of e-waste leads to increased exposure to toxic metals : An occupational exposure study from Sweden
- 2014
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In: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750. ; 73, s. 243-251
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Journal article (peer-reviewed)abstract
- Electrical and electronic waste (e-waste) contains multiple toxic metals. However, there is currently a lack of exposure data for metals on workers in formal recycling plants. The objective of this study was to evaluate workers' exposure to metals, using biomarkers of exposure in combination with monitoring of personal air exposure. We assessed exposure to 20 potentially toxic metals among 55 recycling workers and 10 office workers at three formal e-waste recycling plants in Sweden. Workers at two of the plants were followed-up after 6 months. We collected the inhalable fraction and OFC (37-mm) fraction of particles, using personal samplers, as well as spot samples of blood and urine. We measured metal concentrations in whole blood, plasma, urine, and air filters using inductively coupled plasma-mass spectrometry following acid digestion. The air sampling indicated greater airborne exposure, 10 to 30 times higher, to most metals among the recycling workers handling e-waste than among the office workers. The exposure biomarkers showed significantly higher concentrations of chromium, cobalt, indium, lead, and mercury in blood, urine, and/or plasma of the recycling workers, compared with the office workers. Concentrations of antimony, indium, lead, mercury, and vanadium showed close to linear associations between the inhalable particle fraction and blood, plasma, or urine. In conclusion, our study of formal waste recycling shows that workers performing recycling tasks are exposed to multiple toxic metals.
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| 27. |
- Kordasti, Shirin, 1975, et al.
(author)
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Rotavirus infection is not associated with small intestinal fluid secretion in the adult mouse.
- 2006
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In: Journal of virology. - 0022-538X .- 1098-5514. ; 80:22, s. 11355-61
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Journal article (peer-reviewed)abstract
- In contrast to humans, adult but not infant small animals are resistant to rotavirus diarrhea. The pathophysiological mechanism behind this age-restricted diarrhea is currently unresolved, and this question was investigated by studying the secretory state of the small intestines of adult mice infected with rotavirus. Immunohistochemistry and histological examinations revealed that rotavirus (strain EDIM) infects all parts of the small intestines of adult mice, with significant numbers of infected cells in the ilea at 2 and 4 days postinfection. Furthermore, quantitative PCR revealed that 100-fold more viral RNA was produced in the ilea than in the jejuna or duodena of adult mice. In vitro perfusion experiments of the small intestine did not reveal any significant changes in net fluid secretion among mice infected for 3 days or 4 days or in those that were noninfected (37 +/- 9 microl . h(-1) . cm(-1), 22 +/- 13 microl . h(-1) . cm(-1), and 33 +/- 6 microl . h(-1) . cm(-1), respectively) or in transmucosal potential difference (4.0 +/- 0.3 mV versus 3.9 +/- 0.4 mV), a marker for active chloride secretion, between control and rotavirus-infected mice. In vivo experiments also did not show any differences in potential difference between uninfected and infected small intestines. Furthermore, no significant differences in weight between infected and uninfected small intestines were found, nor were any differences in fecal output observed between infected and control mice. Altogether, these data suggest that rotavirus infection is not sufficient to stimulate chloride and water secretion from the small intestines of adult mice.
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| 28. |
- Kordasti, Shirin, 1975, et al.
(author)
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Serotonin and vasoactive intestinal peptide antagonists attenuate rotavirus diarrhoea.
- 2004
-
In: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 53:7, s. 952-7
-
Journal article (peer-reviewed)abstract
- BACKGROUND AND AIMS: The mechanisms underlying intestinal secretion in rotavirus diarrhoea remain to be established. We previously reported that rotavirus evokes intestinal fluid and electrolyte secretion by activation of the enteric nervous system. We now report that antagonists for the 5-hydroxytryptamine 3 receptor (5-HT(3)) and vasoactive intestinal peptide (VIP) receptor, but not antagonists for 5-hydroxytryptamine 4 receptor or the muscarinic receptor, attenuate rotavirus induced diarrhoea. METHODS: Neurotransmitter antagonists were administered to wild-type or neurokinin 1 receptor knockout mice infected with homologous (EDIM) or heterologous (RRV) rotavirus. RESULTS: While RRV infected mice had diarrhoea for 3.3 (0.2) days (95% confidence interval (CI) 3.04-3.56), the 5-HT(3) receptor antagonist (granisetron) and the VIP receptor antagonist (4Cl-D-Phe(6),Leu(17))-VIP both reduced the total number of days of RRV induced diarrhoea to 2.1 (0.3) (95% CI 1.31-2.9) (p<0.01). EDIM infected mice treated with granisetron had a significantly shorter duration of diarrhoea (5.6 (0.4) days) compared with untreated mice (8.0 (0.4) days; p<0.01). Experiments with neurokinin 1 receptor antagonists suggest that this receptor may possibly be involved in the secretory response to rotavirus. On the other hand, rotavirus diarrhoea was not attenuated in the neurokinin 1 receptor knockout mice. CONCLUSIONS: Our results suggest that the neurotransmitters serotonin and VIP are involved in rotavirus diarrhoea; observations that could imply new principles for treatment of this disease with significant global impact.
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| 29. |
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| 30. |
- Lundgren, Lennart, et al.
(author)
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Do insulation products of man-made vitreous fibres still cause skin discomfort?
- 2014
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In: Contact Dermatitis. - : Wiley. - 0105-1873 .- 1600-0536. ; 70:6, s. 351-360
-
Journal article (peer-reviewed)abstract
- Background. Man-made vitreous fibres (MMVFs) are used in products for insulation and as reinforcement in materials. Contamination of the skin may arise through direct or indirect contact, and from the deposition of airborne fibres. The scientific basis regarding the effects on skin of MMVFs dates from 1970-1980. Objectives. To investigate whether currently used insulation MMVF products still cause skin discomfort. Methods. Focus group interviews and structured interviews were performed among workers engaged in insulation tasks and among do-it-yourself consumers with a recent experience of MMVF products. Results. A majority of interviewees experienced skin discomfort when handling MMVF products. Complaints caused by traditional (yellow) glass fibre products were more severe than those caused by products of rock or slag wool fibres. The wrists, forearms, neck and face were the locations where the skin was most affected. The situations causing problems varied between occupational tasks, but working with the hands over the head or in narrow spaces were described as the worst situations. Building construction apprentices performed insulation tasks more often than senior workers. Conclusions. MMVF insulation products do still cause skin discomfort. Updated knowledge about people's experiences of work with such products should influence legislation.
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| 31. |
- Lundgren, Lennart
(author)
-
Large organic aerosols in a human exposure chamber : applications in occupational dermatology and lung medicine
- 2006
-
Doctoral thesis (other academic/artistic)abstract
- Exposure to large organic aerosol particles may cause respiratory and skin reactions. The use of human exposure chambers offers possibilities for experimental exposure challenges carried out with patients, in research and for investigations of the effects of exposure on the skin and in the respiratory tract. The present aim was to study the performance of modern human whole-body exposure chambers during generation of large organic particles, and to develop and test new measuring techniques for use in exposure studies of the respiratory tract or on the skin. The work reported in the present thesis was based primarily on studies in a whole-body human exposure chamber located at Karolinska University Hospital in Solna, Stockholm, Sweden. This chamber was specially constructed for challenges with aerosols. Dynamically controlled, the chamber is easy to operate. Since human exposure chamber set-ups and designs may vary and yield different performance and dust characteristics, the performance of another human chamber was also evaluated. Performance as a measure of temporal and spatial variability of the aerosol concentration, and aerodynamic particle size, was evaluated for these two chambers based on different airand dust-mixing principles. Temporal and spatial variability close to the breathing zone during exposure was typically <10% in the chamber at Karolinska University Hospital. In a larger section around a human, only slightly higher spatial variation was found. The variability between exposure sessions was also low (<10%). Only limited influence of relative humidity on chamber performance for the evaluated aerosols was observed. Similar performance characteristics with pinewood dust were obtained in both chambers. The particle size distribution curves differed slightly, but some were comparable to those found in occupational environments. Performance as measured with a heated mannequin was almost the same as with humans, indicating that a mannequin can be used in preparatory tests. The temporal variation during an exposure session varied considerably if a neutralizer device for removing static charges in the dust was not connected; here over 20 30% variation was not unusual. A neutralizer greatly decreased this variation to values near 10% as measured in one of the chambers. The same outcome was also found for spatial variation, which was high (over 20%) with no neutralizer. Exposure to wood dust within the woodworking industry causes various respiratory disorders. A study of bronchoalveolar lavage (BAL) fluid from eleven healthy individuals exposed to pinewood dust in one of the chambers revealed an accumulation of eosinophils and T-lymphocytes in the lungs after exposure. Skin exposure to aerosols of allergens and irritants may cause dermatitis. There are few methods for assessing skin exposure to such particles. A vacuuming sampler for removing particles from the skin was constructed and was tested in one of the chambers. This sampler was compared with two other skin and surface sampling techniques, one based on interception (a patch sampler - adhesive tape on an optical cover glass) and one using a tape stripping procedure. All three methods measure the mass of dust on skin. Healthy subjects were exposed to dust of wheat flour and cornstarch. Samples were taken from forearms and shoulders and analysed using optical microscopy. Small differences in the results were obtained. Agreement between the vacuuming sampler and the tape stripping technique was good. The three techniques are applicable for assessing skin exposure to particles and for dose/effect studies. The vacuuming technique allows for dust sampling from large areas of skin.
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| 32. |
- Lundgren, Malin, 1979, et al.
(author)
-
A CPHD Filter for Tracking With Spawning Models
- 2013
-
In: IEEE Journal on Selected Topics in Signal Processing. - 1941-0484 .- 1932-4553. ; 7:3, s. 496-507
-
Journal article (peer-reviewed)abstract
- In some applications of multi-target tracking, appearing targets are suitably modeled as spawning from existing targets. However, in the original formulation of the cardinalized probability hypothesis density (CPHD) filter, this type of model is not supported; instead appearing targets are modeled by spontaneous birth only. In this paper we derive the necessary equations for a CPHD filter for the case when the process model also includes target spawning. For this generalized filter, the cardinality prediction formula might become computationally intractable for general spawning models. However, when the cardinality distribution of the spawning targets is either Bernoulli or Poisson, we derive expressions that are practical and computationally efficient. Simulations show that the proposed filter responds faster to a change in target number due to spawned targets than the original CPHD filter. In addition, the performance of the filter, considering the optimal subpattern assignment (OSPA), is improved when having an explicit spawning model.
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| 33. |
- Lundgren, Malin, 1979, et al.
(author)
-
A CPHD filter for tracking with spawning models - including a FISST based derivation
- 2013
-
Reports (other academic/artistic)abstract
- In some applications of multi-target tracking, appearing targets are suitably modeled as spawning from existing targets. However, in the original formulation of the cardinalized probability hypothesis density (CPHD) filter, this type of model is not supported; instead appearing targets are modeled by spontaneous birth only.In this paper we derive the necessary equations for a CPHD filter for the case when the process model also includes target spawning. For this generalized filter, the cardinality prediction formula might become computationally intractable for general spawning models. However, when the cardinality distribution of the spawning targets is either Bernoulli or Poisson, we derive expressions that are practical and computationally efficient. Simulations show that the proposed filter responds faster to a change in target number due to spawned targets than the original CPHD filter. In addition, the performance of the filter, considering the optimal subpattern assignment (OSPA), is improved when having an explicit spawning model.
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| 34. |
- Lundgren, Malin, 1979, et al.
(author)
-
Variational Bayesian Expectation Maximization for Radar Map Estimation
- 2016
-
In: IEEE Transactions on Signal Processing. - 1941-0476 .- 1053-587X. ; 64:6, s. 1391-1404
-
Journal article (peer-reviewed)abstract
- For self-localization, a detailed and reliable map of the environment can be used to relate sensor data to static features with known locations. This paper presents a method for construction of detailed radar maps that describe the expected intensity of detections. Specifically, the measurements are modelled by an inhomogeneous Poisson process with a spatial intensity function given by the sum of a constant clutter level and an unnormalized Gaussian mixture. A substantial difficulty with radar mapping is the presence of data association uncertainties, i.e., the unknown associations between measurements and landmarks. In this paper, the association variables are introduced as hidden variables in a variational Bayesian expectation maximization (VBEM) framework, resulting in a computationally efficient mapping algorithm that enables a joint estimation of the number of landmarks and their parameters.
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| 35. |
- Lundgren, Malin, 1979, et al.
(author)
-
Vehicle self-localization using off-the-shelf sensors and a detailed map
- 2014
-
In: IEEE Intelligent Vehicles Symposium, Proceedings. - 9781479936380 ; , s. 522-528
-
Conference paper (peer-reviewed)abstract
- In the research on autonomous vehicles, self-localization is an important problem to solve. In this paper we present a localization algorithm based on a map and a set of off-the-shelf sensors, with the purpose of evaluating this low-cost solution with respect to localization performance. The used test vehicle is equipped with a Global Positioning System receiver, a gyroscope, wheel speed sensors, a camera providing information about lane markings, and a radar detecting landmarks along the road. Evaluation shows that the localization result is within or close to the requirements for autonomous driving when lane markers and good radar landmarks are present. However, it also indicates that the solution is not robust enough to handle situations when one of these information sources is absent.
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| 36. |
- Lundgren, Ove, 1937, et al.
(author)
-
Intestinal Epithelial Stem/Progenitor Cells Are Controlled by Mucosal Afferent Nerves
- 2011
-
In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:2, s. 16295-
-
Journal article (peer-reviewed)abstract
- Background: The maintenance of the intestinal epithelium is of great importance for the survival of the organism. A possible nervous control of epithelial cell renewal was studied in rats and mice. Methods: Mucosal afferent nerves were stimulated by exposing the intestinal mucosa to capsaicin (1.6 mM), which stimulates intestinal external axons. Epithelial cell renewal was investigated in the jejunum by measuring intestinal thymidine kinase (TK) activity, intestinal H-3-thymidine incorporation into DNA, and the number of crypt cells labeled with BrdU. The influence of the external gut innervation was minimized by severing the periarterial nerves. Principal Findings: Luminal capsaicin increased all the studied variables, an effect nervously mediated to judge from inhibitory effects on TK activity or H-3-thymidine incorporation into DNA by exposing the mucosa to lidocaine (a local anesthetic) or by giving four different neurotransmitter receptor antagonists i.v. (muscarinic, nicotinic, neurokinin1 (NK1) or calcitonin gene related peptide (CGRP) receptors). After degeneration of the intestinal external nerves capsaicin did not increase TK activity, suggesting the involvement of an axon reflex. Intra-arterial infusion of Substance P (SP) or CGRP increased intestinal TK activity, a response abolished by muscarinic receptor blockade. Immunohistochemistry suggested presence of M3 and M5 muscarinic receptors on the intestinal stem/progenitor cells. We propose that the stem/progenitor cells are controlled by cholinergic nerves, which, in turn, are influenced by mucosal afferent neuron(s) releasing acetylcholine and/or SP and/or CGRP. In mice lacking the capsaicin receptor, thymidine incorporation into DNA and number of crypt cells labeled with BrdU was lower than in wild type animals suggesting that nerves are important also in the absence of luminal capsaicin, a conclusion also supported by the observation that atropine lowered thymidine incorporation into DNA by 60% in control rat segments. Conclusion: Enteric nerves are of importance in maintaining the intestinal epithelial barrier.
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| 37. |
- Lundgren, Oskar, et al.
(author)
-
Mindfulness-Based Stress Reduction for Coronary Artery Disease Patients : Potential Improvements in Mastery and Depressive Symptoms
- 2022
-
In: Journal of clinical psychology in medical settings. - : Springer / Plenum. - 1068-9583 .- 1573-3572. ; 29:3, s. 489-497
-
Journal article (peer-reviewed)abstract
- Depressive symptoms after coronary events are associated with a worse prognosis. When changing the focus from psychopathology towards a resilience framework, treatments such as mindfulness meditation could offer novel ways to address psychological distress among coronary artery disease (CAD) patients. We studied the feasibility of mindfulness-based stress reduction (MBSR) for CAD patients with depressive symptoms. Seventy-nine CAD patients with elevated depressive symptoms were invited to an 8-week MBSR course. Twenty-four patients (30%) accepted and 16 (20%) completed MBSR. Depressive symptoms decreased immediately after the course (p = .006). After 12 months, this improvement remained, and Mastery scores increased (p = .005). A reference group of 108 CAD patients did not show any significant changes in depressive symptoms or Mastery between 1 and 12 months after a coronary event. MBSR thus appears to be a feasible alternative for CAD patients with elevated depressive symptoms. Future studies are warranted to study if MBSR can improve psychological functioning in CAD patients. Clinicaltrials.gov (Registration Number: NCT03340948).
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| 38. |
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| 39. |
- Lundgren, Ove, et al.
(author)
-
Role of the enteric nervous system in the fluid and electrolyte secretion of rotavirus diarrhea
- 2000
-
In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 287:5452, s. 491-495
-
Journal article (peer-reviewed)abstract
- The mechanism underlying the intestinal fluid loss in rotavirus diarrhea, which often afflicts children in developing countries, is not known. One hypothesis is that the rotavirus evokes intestinal fluid and electrolyte secretion by activation of the nervous system in the intestinal wall, the enteric nervous system (ENS). Four different drugs that inhibit ENS functions were used to obtain experimental evidence for this hypothesis in mice in vitro and in vivo. The involvement of the ENS in rotavirus diarrhea indicates potential sites of action for drugs in the treatment of the disease.
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| 40. |
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| 41. |
- Lundgren, Tobias, et al.
(author)
-
Acceptance and Commitment Therapy and yoga for drug-refractory epilepsy : A randomized controlled trial
- 2008
-
In: Epilepsy & Behavior. - : Elsevier BV. - 1525-5050 .- 1525-5069. ; 13:1, s. 102-108
-
Journal article (peer-reviewed)abstract
- Objective. There is a need for controlled outcome studies on behavioral treatment of epilepsy. The purpose of this study was to evaluate Acceptance and Commitment Therapy (ACT) and yoga in the treatment of epilepsy. Methods. The design consisted of a randomized controlled trial with repeated measures (N = 18). All participants had an EEG-verified epilepsy diagnosis with drug-refractory seizures. Participants were randomized into one of two groups: ACT or yoga. Therapeutic effects were measured using seizure index (frequency x duration) and quality of life (Satisfaction with Life Scale, WHOQOL-BREF). The treatment protocols consisted of 12 hours of professional therapy distributed in two individual sessions, two group sessions during a 5-week period, and booster sessions at 6 and 12 months posttreatment. Seizure index was continuously assessed during the 3-month baseline and 12-month follow-up. Quality of life was measured after treatment and at the 6-month and 1-year follow-ups. Results. The results indicate that both ACT and yoga significantly reduce seizure index and increase quality of life over time. ACT reduced seizure index significantly more as compared with yoga. Participants in both the ACT and yoga groups improved their quality of life significantly as measured by one of two quality-of-life instruments. The ACT group increased their quality of life significantly as compared with the yoga group as measured by the WHOQOL-BREF, and the yoga group increased their quality of life significantly as compared with the ACT group as measured by the SWLS. Conclusions. The results of this study suggest that complementary treatments, such as ACT and yoga, decrease seizure index and increase quality of life.
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| 42. |
- Lundgren, Tobias, et al.
(author)
-
Evaluation of acceptance and commitment therapy for drug refractory epilepsy : A randomized controlled trial in South Africa - A pilot study
- 2006
-
In: Epilepsia. - : Wiley. - 0013-9580 .- 1528-1167. ; 47:12, s. 2173-2179
-
Journal article (peer-reviewed)abstract
- Purpose: Psychological interventions in the treatment of epilepsy have been developed and evaluated for many years but the amount of research has hardly made an impact on how epilepsy is treated. The purpose of this study was to develop and evaluate a psychological treatment program consisting of Acceptance and Commitment Therapy together with some behavioral seizure control technology shown to be successful in earlier research. Methods: The method consisted of a RCT group design with repeated measures (N= 27). All participants had an EEG verified epilepsy diagnosis with drug refractory seizures. Participants were randomized into one of two conditions, ACT or Supportive therapy (ST). Therapeutic effects were measured by examining changes in quality of life (SWLS and WHOQOL) and seizure index (frequency * duration). Both treatment conditions consisted of only 9 hours of professional therapy distributed in two individual and two group sessions during a four-week period. Results: The results showed significant effects over all of the dependent variables for the ACT group as compared to the ST group at 6 and twelve-month follow ups. Conclusions: The results from this study suggest that a short-term psychotherapy program combined with anticonvulsant drugs may help to prevent the long-term disability that occurs from drug refractory seizures.
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| 43. |
- Lundgren, Tobias, et al.
(author)
-
Preliminary Investigation of Executive Functions in Elite Ice Hockey Players
- 2016
-
In: Journal of Clinical Sport Psychology. - : Human Kinetics. - 1932-9261 .- 1932-927X. ; 10:4, s. 324-335
-
Journal article (peer-reviewed)abstract
- Elite level ice hockey places high demands on player’s physical and technical attributes as well as on cognitive and executive functions. There is, however, a notable lack of research on these attributes and functions. The present study investigated executive function with selected tests from the D-KEFS test battery among 48 ice hockey players and compared them to a standardized sample. Results show that ice hockey players’ scores were significantly higher on Design Fluency (DF) compared with the standardized sample score. Elite players’ scores were not significantly higher than those of lower-league hockey players. A significant correlation was found between on-ice performance and Trail Making Test (TMT) scores. Exploratory analysis showed that elite-level center forwards scored significantly higher on DF than did players in other positions. Future research should investigate whether assessment of executive function should be taken into account, in addition to physical and technical skills, when scouting for the next ice hockey star.
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| 44. |
- Lundgren, Tobias, et al.
(author)
-
The Bull's-Eye Values Survey : A Psychometric Evaluation
- 2012
-
In: Cognitive and Behavioral Practice. - : Elsevier BV. - 1077-7229 .- 1878-187X. ; 19:4, s. 518-526
-
Journal article (peer-reviewed)abstract
- Purpose: Two studies were conducted to develop and evaluate an instrument attempting to identify and measure personal values, values attainment and believability in thoughts functioning as obstacles in living a valued life. Study one describes a content validity approach to the construction and preliminary validation of the Bull’s Eye Values Survey (BEVS), using a sample of institutionalized patients suffering from Epilepsy. Study Two investigated the psychometric properties of the BEVS with a sample of Swedish university students. Results indicate that the BEVS is sensitive to treatment effects and can differentiate between clients who receive values based interventions and those that do not. The BEVS subscales and total score appear to measure an independent dimension of psychological functioning that is negatively correlated with measures of depression, anxiety and stress and positively correlated with a measure of psychological flexibility. The BEVS also exhibits acceptable temporal stability and internal consistency. The study provides preliminary support for the BEVS as both a research and clinical tool for measuring values, valued action discrepancies and barriers to value based living.
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| 45. |
- Nilforoush, Rasoul
(author)
-
Anchorage in Concrete Structures : Numerical and Experimental Evaluations of Load-Carrying Capacity of Cast-in-Place Headed Anchors and Post-Installed Adhesive Anchors
- 2017
-
Doctoral thesis (other academic/artistic)abstract
- Various anchorage systems including both cast-in-place and post-installed anchors have been developed for fastening both non-structural and structural components to concrete structures. The need for increased flexibility in the design of new structures and strengthening of existing concrete structures has led to increased use of various metallic anchors in practice. Although millions of fasteners are used each year in the construction industry around the world, knowledge of the fastening technology remains poor. In a sustainable society, buildings and structures must, from time to time, be adjusted to meet new demands. Loads on structures must, in general, be increased to comply with new demands, and the structural components and the structural connections must also be upgraded. From the structural connection point of view, the adequacy of the current fastenings for the intended increased load must be determined, and inadequate fastenings must either be replaced or upgraded. The current design models are generally believed to be conservative, although the extent of this behavior is not very clear. To address these issues, the current models must be refined to allow the design of new fastenings and also the assessment of current anchorage systems in practice.The research presented in this thesis consists of numerical and experimental studies of the load-carrying capacity of anchors in concrete structures. Two different types of anchors were studied: (I) cast-in-place headed anchors, and (II) post-installed adhesive anchors. This research focused particularly on the tensile load-carrying capacity of cast-in-place headed anchors and also on the sustained tension loading performance of post-installed adhesive anchors. The overall objective of this research was to provide knowledge for the development of improved methods of designing new fastening systems and assessing the current anchorage systems in practice.For the cast-in-place headed anchors (I), the influence of various parameters including the size of anchor head, thickness of concrete member, amount of orthogonal surface reinforcement, presence of concrete cracks, concrete compressive strength, and addition of steel fibers to concrete were studied. Among these parameters, the influence of the anchor head size, member thickness, surface reinforcement, and cracked concrete was initially evaluated via numerical analysis of headed anchors at various embedment depths. Although these parameters have considerable influence on the anchorage capacity and performance, this influence is not explicitly considered by the current design models. The numerical results showed that the tensile breakout capacity of headed anchors increases with increasing member thickness and/or increasing size of the anchor head or the use of orthogonal surface reinforcement. However, their capacity decreased considerably in cracked concrete. Based on the numerical results, the current theoretical model for the tensile breakout capacity of headed anchors was extended by incorporating several modification factors that take the influence of the investigated parameters into account. In addition, a supplementary experimental study was performed to verify the numerically obtained findings and the proposed refined model. The experimental results corresponded closely to the numerical results, both in terms of failure load and failure pattern, thereby confirming the validity of the proposed model. The validity of the model was further confirmed through experimental results reported in the literature.Additional experiments were performed to determine the influence of the concrete compressive strength and the addition of steel fiber to concrete on the anchorage capacity and performance. These experiments showed that the anchorage capacity and stiffness increase considerably with increasing concrete compressive strength, but the ductility of the anchor decreases. However, the anchorage capacity and ductility increased significantly with the addition of steel fibers to the concrete mixture. The test results also revealed that the tensile breakout capacity of headed anchors in steel fiber-reinforced concrete is significantly underestimated by the current design model.The long-term performance and creep behavior of the post-installed headed anchors (II) was evaluated from the results of long-time tests on adhesive anchors under sustained loads. In this experimental study, adhesive anchors of various sizes were subjected to various sustained load levels for up to 28 years. The anchors were also exposed to several in-service conditions including indoor temperature, variations in the outdoor temperature and humidity, wetness (i.e., water on the surface of concrete), and the presence of salt (setting accelerant) additives in the concrete. Among the tested in-service conditions, variations in the outdoor temperature and humidity had the most adverse effect on the long-term sustained loading performance of the anchors. Based on the test results, recommendations were proposed for maximum sustained load levels under various conditions. The anchors tested under indoor conditions could carry sustained loads of up to 47% of their mean ultimate short-term capacities. However, compared with these anchors, the anchors tested under outdoor conditions exhibited larger creep deformation and failure occurred at sustained loads higher than 23% of their mean ultimate short-term capacities. Salt additives in concrete and wet conditions had negligible influence on the long-term performance of the anchors, although the wet condition resulted in progressive corrosion of the steel. Based on the experimental results, the suitability of the current testing and approval provisions for qualifying adhesive anchors subjected to long-term sustained tensile loads was evaluated. The evaluations revealed that the current approval provisions are not necessarily reliable for qualifying adhesive anchors for long-term sustained loading applications. Recommendations were given for modifying the current provisions to ensure safe long-term performance of adhesive anchors under sustained loads.
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| 46. |
- Omran, Meis, et al.
(author)
-
Whole-Body MRI Surveillance : Baseline Findings in the Swedish Multicentre Hereditary TP53-Related Cancer Syndrome Study (SWEP53)
- 2022
-
In: Cancers. - : MDPI. - 2072-6694. ; 14:2
-
Journal article (peer-reviewed)abstract
- A surveillance strategy of the heritable TP53-related cancer syndrome (hTP53rc), commonly referred to as the Li–Fraumeni syndrome (LFS), is studied in a prospective observational nationwide multi-centre study in Sweden (SWEP53). The aim of this sub-study is to evaluate whole-body MRI (WB-MRI) regarding the rate of malignant, indeterminate, and benign imaging findings and the associated further workup generated by the baseline examination. Individuals with hTP53rc were enrolled in a surveillance program including annual whole-body MRI (WB-MRI), brain-MRI, and in female carriers, dedicated breast MRI. A total of 68 adults ≥18 years old have been enrolled to date. Of these, 61 fulfilled the inclusion criteria for the baseline MRI scan. In total, 42 showed a normal scan, while 19 (31%) needed further workup, of whom three individuals (3/19 = 16%) were diagnosed with asymptomatic malignant tumours (thyroid cancer, disseminated upper GI cancer, and liver metastasis from a previous breast cancer). Forty-three participants were women, of whom 21 had performed risk-reducing mastectomy prior to inclusion. The remaining were monitored with breast MRI, and no breast tumours were detected on baseline MRI. WB-MRI has the potential to identify asymptomatic tumours in individuals with hTP53rc syndrome. The challenge is to adequately and efficiently investigate all indeterminate findings. Thus, a multidisciplinary team should be considered in surveillance programs for individuals with hTP53rc syndrome.
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| 47. |
- Omran, Meis, et al.
(author)
-
Whole-body MRI surveillance in TP53 carriers is perceived as beneficial with no increase in cancer worry regardless of previous cancer : Data from the Swedish TP53 Study
- 2023
-
In: Cancer. - : Wiley. - 0008-543X .- 1097-0142. ; 129:6, s. 946-955
-
Journal article (peer-reviewed)abstract
- Background: To evaluate the psychosocial consequences of surveillance with whole-body MRI (WB-MRI) in individuals with the heritable TP53-related cancer (hTP53rc) syndrome, also known as the Li-Fraumeni syndrome, with regard to cancer worry, perceived benefits and risks to surveillance and overall health. Patients and methods: Since 2016, the national Swedish TP53 Study (SWEP53) has offered surveillance with WB-MRI to all individuals with hTP53rc syndrome. Seventy-five individuals have been included in the study. Sixty consecutive participants fulfilled a base-line evaluation as well as an evaluation after 1 year with structured questionnaires including the Cancer Worry Scale (CWS), perceived benefits and risks of surveillance, and the 36-item Short Form Survey (SF-36). Individuals with or without previous personal cancer diagnosis were enrolled and results at baseline and after 1 year of surveillance were compared. For SF-36, a comparison with the normal population was also made. Results: Participants with previous cancer tend to worry more about cancer, but both individuals with and without cancer had a positive attitude toward surveillance with no differences regarding perceived benefits and barriers to surveillance. Participants with a previous cancer scored significantly lower on some of the SF-36 subscales, but between-group differences were found only for social functioning after 1 year. Conclusions: Surveillance with WB-MRI is feasible from a psychosocial point of view both among TP53 carriers with as well as without a previous history of cancer and does not increase cancer worry in any of the groups. Plain language summary: Individuals with heritable TP53-related cancer syndrome (also known as the Li-Fraumeni syndrome) have a high lifetime risk of developing cancer. These TP53 carriers are offered surveillance with whole-body MRI to detect cancer early. There are few reports of the psychosocial impact of surveillance. In this study, we wanted to evaluate cancer worry, benefits and barriers to participation, and perceived overall health. Our study shows no increase in cancer worry after 1 year of surveillance, regardless of previous cancer.
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| 48. |
- Palmqvist, Py, 1968-, et al.
(author)
-
IL-1beta and TNF-alpha regulate IL-6-type cytokines in gingival fibroblasts.
- 2008
-
In: Journal of Dental Research. - : SAGE Publications. - 0022-0345 .- 1544-0591. ; 87:6, s. 558-563
-
Journal article (peer-reviewed)abstract
- Interleukin-6 (IL-6)-type cytokines are pleiotropic molecules capable of stimulating bone resorption and expressed by numerous cell types. In the present study, we tested the hypothesis that gingival fibroblasts may exert local osteotropic effects through production of IL-6 and related cytokines. IL-6-type cytokine expression and regulation by IL-1beta and tumor necrosis factor-alpha (TNF-alpha) were studied in fibroblasts from the non-inflamed gingiva of healthy individuals. Constitutive mRNA expression of IL-6, IL-11, and leukemia inhibitory factor (LIF), but not of oncostatin M (OSM), was demonstrated, as was concentration-dependent stimulation of IL-6 and LIF mRNA and of protein by IL-1beta and TNF-alpha. IL-11 mRNA and protein were concentration-dependently stimulated by IL-1beta. The signaling pathway involved in IL-6 and LIF mRNA stimulation involved MAP kinases, but not NF-kappaB. The findings support the view that resident cells may influence the pathogenesis of periodontal disease through osteotropic IL-6-type cytokine production mediated by activation of MAP kinases. Abbreviations: IL-1alpha (interleukin-1alpha); IL-1beta (interleukin-1beta); IL-6 (interleukin-6); IL-11 (interleukin-11); LIF (leukemia inhibitory factor); OSM (oncostatin M); alpha(1)-coll. I (alpha(1)-collagen I); ALP (alkaline phosphatase); BMP-2 (bone morphogenetic protein-2); OC (osteocalcin); BSP (bone sialoprotein); TNFR I (tumor necrosis factor receptor I); TNFR II (tumor necrosis factor receptor II); IL-1R1 (interleukin-1 receptor 1); GAPDH (glyceraldehyde-3-phosphate dehydrogenase); RPL13A (ribosomal protein L13A); mRNA (messenger ribonucleic acid); cDNA (complementary deoxyribonucleic acid); PCR (polymerase chain-reaction); BCA (bicinchoninic acid); ELISA (enzyme-linked immunosorbent assay); alpha-MEM (alpha modification of Minimum Essential Medium); and FCS (fetal calf serum).
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| 49. |
- Palmqvist, Py, et al.
(author)
-
Interleukin-4 and interleukin-13 inhibit the expression of leukemia inhibitory factor and interleukin-11 in fibroblasts.
- 2012
-
In: Molecular immunology. - : Elsevier BV. - 1872-9142 .- 0161-5890. ; 49:4, s. 601-10
-
Journal article (peer-reviewed)abstract
- Cytokines produced by inflammatory or resident mesenchymal cells play important modulatory roles in the pathogenesis of inflammation induced bone loss. In the present study, the effects of IL-4 and IL-13 on the expression of three osteotropic cytokines in the IL-6 family expressed in human gingival fibroblasts were studied. IL-4Rα and IL-13Rα1 mRNA were constitutively expressed in human gingival fibroblasts. The inflammatory cytokines IL-1β and TNF-α increased expression of IL-6, LIF, and IL-11 mRNA and protein in the gingival fibroblasts. Addition of IL-4 or IL-13 had no effect on IL-6 expression, but significantly inhibited LIF and IL-11 mRNA and protein stimulated by IL-1β and TNF-α. No involvement of NF-κB or STAT1 was observed in the inhibition. STAT6 was phosphorylated at Y641 by treatment with IL-4 and knockdown of STAT6 with siRNA decreased the inhibition of IL-11 and LIF expression by IL-4 in IL-1β and TNF-α stimulated cells. This study suggests that activation of STAT6 by IL-4 and IL-13, through type 2 IL-4 receptors, inhibits production of IL-11 and LIF stimulated by IL-1β and TNF-α in human gingival fibroblasts. A negative modulatory role of IL-4 and IL-13 in osteotropic cytokine production could be a mechanism playing an important inhibitory role in inflammation induced periodontitis.
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| 50. |
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