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Sökning: WFRF:(Ljunggren Stefan)

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1.
  • Abelev, Betty, et al. (författare)
  • Long-range angular correlations on the near and away side in p-Pb collisions at root S-NN=5.02 TeV
  • 2013
  • Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 29-41
  • Tidskriftsartikel (refereegranskat)abstract
    • Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5 < P-T,P-assoc < P-T,P-trig < 4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and p(T) bins, and the widths show no significant evolution with event multiplicity or p(T). These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge. (c) 2013 CERN. Published by Elsevier B.V. All rights reserved.
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2.
  • Ali, Neserin, et al. (författare)
  • Comprehensive proteome analysis of nasal lavage samples after controlled exposure to welding nanoparticles shows an induced acute phase and a nuclear receptor, LXR/RXR, activation that influence the status of the extracellular matrix
  • 2018
  • Ingår i: Clinical Proteomics. - : Springer Science and Business Media LLC. - 1542-6416 .- 1559-0275. ; 15:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Epidemiological studies have shown that many welders experience respiratory symptoms. During the welding process a large number of airborne nanosized particles are generated, which might be inhaled and deposited in the respiratory tract. Knowledge of the underlying mechanisms behind observed symptoms is still partly lacking, although inflammation is suggested to play a central role. The aim of this study was to investigate the effects of welding fume particle exposure on the proteome expression level in welders suffering from respiratory symptoms, and changes in protein mediators in nasal lavage samples were analyzed. Such mediators will be helpful to clarify the pathomechanisms behind welding fume particle-induced effects. Methods: In an exposure chamber, 11 welders with work-related symptoms in the lower airways during the last month were exposed to mild-steel welding fume particles (1 mg/m3) and to filtered air, respectively, in a double-blind manner. Nasal lavage samples were collected before, immediately after, and the day after exposure. The proteins in the nasal lavage were analyzed with two different mass spectrometry approaches, label-free discovery shotgun LC-MS/MS and a targeted selected reaction monitoring LC-MS/MS analyzing 130 proteins and four in vivo peptide degradation products. Results: The analysis revealed 30 significantly changed proteins that were associated with two main pathways; activation of acute phase response signaling and activation of LXR/RXR, which is a nuclear receptor family involved in lipid signaling. Connective tissue proteins and proteins controlling the degradation of such tissues, including two different matrix metalloprotease proteins, MMP8 and MMP9, were among the significantly changed enzymes and were identified as important key players in the pathways. Conclusion: Exposure to mild-steel welding fume particles causes measurable changes on the proteome level in nasal lavage matrix in exposed welders, although no clinical symptoms were manifested. The results suggested that the exposure causes an immediate effect on the proteome level involving acute phase proteins and mediators regulating lipid signaling. Proteases involved in maintaining the balance between the formation and degradation of extracellular matrix proteins are important key proteins in the induced effects.
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3.
  • Alriksson, Stina, 1971-, et al. (författare)
  • Temporal risk assessment – 20th century Pb emissions to air and exposure via inhalation in the Swedish glass district
  • 2023
  • Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 858:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The objective of the present study was to assess historical emissions of Pb to air around a number of glassworks sites in southeastern Sweden, and the possible implications for human exposure. To do so, a four-step method was applied. First, emissions of Pb to air around 10 glassworks were modelled for the 20th century. Second, an assessment of the resulting exposure was made for a number of scenarios. Third, the number of people potentially exposed at different times was estimated, and fourth, measurements of “current” Pb concentrations in PM10 material from four sites were conducted in 2019. The results show that the highest emissions, and exposures, occurred from 1970 to1980. It coincides with the time period when the highest number of people resided in the villages. At this time, the average Pb concentration in air around the six largest factories was about 2.4 μg Pb/m3, i.e. 16 times the present US national ambient air quality standard (NAAQS) of 0.15 μg Pb/m3. By year 2000 the modelled average concentration had dropped to 0.05 μg Pb/m3, a level that is normal for urban regions today. The PM10 measurements from 2019 indicate a further decline, now with a mean value of about 0.02 μg Pb/m3. Over the entire study period, inhalation hazard quotients (HQs) exceeded the dietary HQ by many orders of magnitude, indicating that inhalation has been the most prevalent exposure pathway in the past. At present, both pathways are judged to be associated with low exposures. Even if only roughly approximated, a picture of the historical exposure can increase our understanding of the connection between exposure and disease, and can be valuable when risks are to be communicated to residents near contaminated areas.
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4.
  • Alvarez-Rodriguez, Manuel, et al. (författare)
  • Exosomes in specific fractions of the boar ejaculate contain CD44: A marker for epididymosomes?
  • 2019
  • Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 140, s. 143-152
  • Tidskriftsartikel (refereegranskat)abstract
    • Seminal plasma (SP) is a complex fluid containing proteins, peptides, enzymes, hormones as well as extracellular vesicles (EVs). The SP interacts with spermatozoa and the inner cell lining of the female genital tract, adsorbing proteins and exosomes that modulate sperm functions and female immune responsiveness. In the present study, boar sperm-free SP was studied using flow cytometry (FC) after membrane tetraspanins (CD9, CD63 and CD81) and membrane receptor CD44 marking of non-enriched (whole SP) or gradient fractions enriched through two-step discontinuous KBr-density-gradient ultracentrifugation, in whole ejaculate or in selected ejaculate fractions. The results, evaluated by transmission electron microscopy, confirmed the presence of exosomes in all fractions of the pig SP. Noteworthy, these pig SP-exosomes were CD44-bearing when analysed by FC, with bands detected by western blotting (WB) at the expected 85 kD size. The two-step discontinuous KBr-density-gradient ultracentrifugation enriched the population of exosomes in two specific gradient fractions, indicating exosomes (either prostasomes or epididymosomes) could be separated from low-density lipoprotein (LDL) but they co-sediment with the high-density lipoprotein (HDL)-bearing fraction. The findings pave for the selective isolation of exosomes in functional studies of their function when interacting with spermatozoa, the oocyte and/or the female genitalia, including hyaluronan-CD44 interplay. (C) 2019 Elsevier Inc. All rights reserved.
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5.
  • Assarsson, Erika, et al. (författare)
  • Severe defect in thymic development in an insertional mutant mouse model.
  • 2007
  • Ingår i: Journal of immunology (Baltimore, Md. : 1950). - : The American Association of Immunologists. - 0022-1767 .- 1550-6606. ; 178:8, s. 5018-5027
  • Tidskriftsartikel (refereegranskat)abstract
    • Transgenic mice were generated expressing NK1.1, an NK cell-associated receptor, under control of the human CD2 promoter. Unexpectedly, one of the founder lines, Tg66, showed a marked defect in thymic development characterized by disorganized architecture and small size. Mapping of the transgene insertion by fluorescence in situ hybridization revealed integration in chromosome 2, band G. Already from postnatal day 3, the thymic architecture was disturbed with a preferential loss of cortical thymic epithelial cells, a feature that became more pronounced over time. Compared with wild-type mice, total thymic cell numbers decreased dramatically between 10 and 20 days of age. Thymocytes isolated from adult Tg66 mice were predominantly immature double-negative cells, indicating a block in thymic development at an early stage of differentiation. Consequently, Tg66 mice had reduced numbers of peripheral CD4(+) and CD8(+) T cells. Bone marrow from Tg66 mice readily reconstituted thymi of irradiated wild-type as well as RAG-deficient mice. This indicates that the primary defect in Tg66 mice resided in nonhemopoietic stromal cells of the thymus. The phenotype is observed in mice heterozygous for the insertion and does not resemble any known mutations affecting thymic development. Preliminary studies in mice homozygous for transgene insertion reveal a more accelerated and pronounced phenotype suggesting a semidominant effect. The Tg66 mice may serve as a useful model to identify genes regulating thymic epithelial cell differentiation, thymic development, and function.
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6.
  • Assenhöj, Maria, et al. (författare)
  • Metal exposure from additive manufacturing and its effect on the nasal lavage fluid proteome - a pilot study
  • 2021
  • Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 16:8
  • Tidskriftsartikel (refereegranskat)abstract
    • The use of metal additive manufacturing (AM) is steadily increasing and is an emerging concern regarding occupational exposure. In this study, non-invasive sampled nasal lavage fluid (NLF) from the upper airways was collected from metal AM operators at the beginning and end of a workweek during two consecutive years with preventive interventions in the occupational setting in-between (n = 5 year 1, n = 9 year 2). During year one, NLF was also collected from welders (n = 6) from the same company to get a comparison with a traditional manufacturing technique with known exposure and health risks. The samples were investigated using untargeted proteomics, as well as using multi-immunoassay to analyze a panel of 71 inflammatory protein markers. NLF in AM operators from year 1 showed decreased levels of Immunoglobulin J and WAP four-disulfide core domain protein 2 and increased levels of Golgi membrane protein 1, Uteroglobin and Protein S100-A6 at the end of the workweek. At year two, after preventive interventions, there were no significant differences at the end of the workweek. In welders, Annexin A1 and Protein S100-A6 were increased at the end of the workweek. The analysis of 71 inflammatory biomarkers showed no significant differences between the beginning and the end of workweek year 1 in AM operators. We identified several proteins of interest in the AM operators that could serve as possible markers for exposure in future studies with a larger cohort for validation.
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7.
  • Assenhöj, Maria, et al. (författare)
  • Occupational exposure and health surveys at metal additive manufacturing facilities
  • 2023
  • Ingår i: Frontiers In Public Health. - : FRONTIERS MEDIA SA. - 2296-2565. ; 11
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction: Additive manufacturing is a novel state-of-the art technology with significant economic and practical advantages, including the ability to produce complex structures on demand while reducing the need of stocking materials and products. Additive manufacturing is a technology that is here to stay; however, new technologies bring new challenges, not only technical but also from an occupational health and safety perspective. Herein, leading Swedish companies using metal additive manufacturing were studied with the aim of investigating occupational exposure and the utility of chosen exposure- and clinical markers as predictors of potential exposure-related health risks.Methods: Exposure levels were investigated by analysis of airborne dust and metals, alongside particle counting instruments measuring airborne particles in the range of 10 nm-10 mu m to identify dusty work tasks. Health examinations were performed on a total of 48 additive manufacturing workers and 39 controls. All participants completed a questionnaire, underwent spirometry, and blood and urine sampling. A subset underwent further lung function tests.Results: Exposure to inhalable dust and metals were low, but particle counting instruments identified specific work tasks with high particle emissions. Examined health parameters were well within reference values on a group level. However, statistical analysis implied an impact on workers kidney function and possible airway inflammation.Conclusion: The methodology was successful for investigating exposure-related health risks in additive manufacturing. However, most participants have been working <5 years. Therefore, long-term studies are needed before we can conclusively accept or reject the observed effects on health.
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8.
  • Assenhöj, Maria, et al. (författare)
  • Protein interaction, monocyte toxicity and immunogenic properties of cerium oxide crystals with 5% or 14% gadolinium, cobalt oxide and iron oxide nanoparticles–an interdisciplinary approach
  • 2021
  • Ingår i: Nanotoxicology. - : Taylor and Francis Ltd.. - 1743-5390 .- 1743-5404. ; 15:8, s. 1035-1038
  • Tidskriftsartikel (refereegranskat)abstract
    • Metal oxide nanoparticles are widely used in both consumer products and medical applications, but the knowledge regarding exposure-related health effects is limited. However, it is challenging to investigate nanoparticle interaction processes with biological systems. The overall aim of this project was to improve the possibility to predict exposure-related health effects of metal oxide nanoparticles through interdisciplinary collaboration by combining workflows from the pharmaceutical industry, nanomaterial sciences, and occupational medicine. Specific aims were to investigate nanoparticle-protein interactions and possible adverse immune reactions. Four different metal oxide nanoparticles; CeOx nanocrystals with 5% or 14% Gd, Co3O4, and Fe2O3, were characterized by dynamic light scattering and high-resolution transmission electron microscopy. Nanoparticle-binding proteins were identified and screened for HLA-binding peptides in silico. Monocyte interaction with nanoparticle–protein complexes was assessed in vitro. Herein, for the first time, immunogenic properties of nanoparticle-binding proteins have been characterized. The present study indicates that especially Co3O4-protein complexes can induce both ‘danger signals’, verified by the production of inflammatory cytokines and simultaneously bind autologous proteins, which can be presented as immunogenic epitopes by MHC class II. The clinical relevance of these findings should be further evaluated to investigate the role of metal oxide nanoparticles in the development of autoimmune disease. The general workflow identified experimental difficulties, such as nanoparticle aggregate formation and a lack of protein-free buffers suitable for particle characterization, protein analyses, as well as for cell studies. This confirms the importance of future interdisciplinary collaborations. © 2021 The Author(s). 
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9.
  • Ausmees, Nora, et al. (författare)
  • Structural and putative regulatory genes involved in cellulose synthesis in Rhizobium leguminosarum bv. trifolii
  • 1999
  • Ingår i: Microbiology. - : Microbiology Society. - 1350-0872 .- 1465-2080. ; 145, s. 1253-1262
  • Tidskriftsartikel (refereegranskat)abstract
    • Six genes involved in cellulose synthesis in Rhizobium leguminosarum bv. trifolii were identified using Tn5 mutagenesis. Four of them displayed homology to the previously cloned and sequenced Agrobacterium tumefaciens cellulose genes celA, celB, celC and celE. These genes are organized similarly in R. leguminosarum bv. trifolii. In addition, there were strong indications that two tandemly located genes, celR1 and celR2, probably organized as one operon, are involved in the regulation of cellulose synthesis. The deduced amino acid sequences of these genes displayed a high degree of similarity to the Caulobacter crescentus DivK and PleD proteins that belong to the family of two-component response regulators. This is to our knowledge the first report of genes involved in the regulation of cellulose synthesis. Results from attachment assays and electron microscopic studies indicated that cellulose synthesis in R. leguminosarum bv. trifolii is induced upon close contact with plant roots during the attachment process.
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10.
  • Beazer, Jack D., et al. (författare)
  • High-density lipoproteins vascular protective functions in metabolic and cardiovascular disease - could extracellular vesicles be at play?
  • 2020
  • Ingår i: Clinical Science. - : Portland Press on behalf of the Medical Research Society and the Biochemical Society. - 0143-5221 .- 1470-8736. ; 134:22, s. 2977-2986
  • Forskningsöversikt (refereegranskat)abstract
    • High-density lipoprotein (HDL) is a circulating complex of lipids and proteins known primarily for its role in reverse cholesterol transport and consequent protection from atheroma. In spite of this, therapies aimed at increasing HDL concentration do not reduce the risk of cardiovascular disease (CVD), and as such focus has shifted towards other HDL functions protective of vascular health - including vasodilatory, anti-inflammatory, antioxidant and anti-thrombotic actions. It has been demonstrated that in disease states such as CVD and conditions of insulin resistance such as Type 2 diabetes mellitus (T2DM), HDL function is impaired owing to changes in the abundance and function of HDL-associated lipids and proteins, resulting in reduced vascular protection. However, the gold standard density ultracentrifugation technique used in the isolation of HDL also co-isolates extracellular vesicles (EVs). EVs are ubiquitous cell-derived particles with lipid bilayers that carry a number of lipids, proteins and DNA/RNA/miRNAs involved in cell-to-cell communication. EVs transfer their bioactive load through interaction with cell surface receptors, membrane fusion and endocytic pathways, and have been implicated in both cardiovascular and metabolic diseases - both as protective and pathogenic mediators. Given that studies using density ultracentrifugation to isolate HDL also co-isolate EVs, biological effects attributed to HDL may be confounded by EVs. We hypothesise that some of HDLs vascular protective functions in cardiovascular and metabolic disease may be mediated by EVs. Elucidating the contribution of EVs to HDL functions will provide better understanding of vascular protection and function in conditions of insulin resistance and potentially provide novel therapeutic targets for such diseases.
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11.
  • Bodin, Helena, 1964-, et al. (författare)
  • Afterword. World literature in the making
  • 2022
  • Ingår i: Literature and the Making of the World. - London : Bloomsbury Academic. - 9781501374159 - 9781501374173 - 9781501374166 - 9781501374180 ; , s. 307-311
  • Bokkapitel (refereegranskat)
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12.
  • Estrada, Karol, et al. (författare)
  • Genome-wide meta-analysis identifies 56 bone mineral density loci and reveals 14 loci associated with risk of fracture.
  • 2012
  • Ingår i: Nature genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 44:5, s. 491-501
  • Tidskriftsartikel (refereegranskat)abstract
    • Bone mineral density (BMD) is the most widely used predictor of fracture risk. We performed the largest meta-analysis to date on lumbar spine and femoral neck BMD, including 17 genome-wide association studies and 32,961 individuals of European and east Asian ancestry. We tested the top BMD-associated markers for replication in 50,933 independent subjects and for association with risk of low-trauma fracture in 31,016 individuals with a history of fracture (cases) and 102,444 controls. We identified 56 loci (32 new) associated with BMD at genome-wide significance (P < 5 × 10(-8)). Several of these factors cluster within the RANK-RANKL-OPG, mesenchymal stem cell differentiation, endochondral ossification and Wnt signaling pathways. However, we also discovered loci that were localized to genes not known to have a role in bone biology. Fourteen BMD-associated loci were also associated with fracture risk (P < 5 × 10(-4), Bonferroni corrected), of which six reached P < 5 × 10(-8), including at 18p11.21 (FAM210A), 7q21.3 (SLC25A13), 11q13.2 (LRP5), 4q22.1 (MEPE), 2p16.2 (SPTBN1) and 10q21.1 (DKK1). These findings shed light on the genetic architecture and pathophysiological mechanisms underlying BMD variation and fracture susceptibility.
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13.
  • Hahn, Robert, et al. (författare)
  • A simple intravenous glucose tolerance test for assessment of insulin sensitivity
  • 2011
  • Ingår i: Theoretical Biology and Medical Modelling. - : BioMed Central. - 1742-4682. ; 8:12
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundThe aim of the study was to find a simple intravenous glucose tolerance test (IVGTT) that can be used to estimate insulin sensitivity.MethodsIn 20 healthy volunteers aged between 18 and 51 years (mean, 28) comparisons were made between kinetic parameters derived from a 12-sample, 75-min IVGTT and the Mbw (glucose uptake) obtained during a hyperinsulinemic euglycemic glucose clamp. Plasma glucose was used to calculate the volume of distribution (Vd) and the clearance (CL) of the injected glucose bolus. The plasma insulin response was quantified by the area under the curve (AUCins). Uptake of glucose during the clamp was corrected for body weight (Mbw).ResultsThere was a 7-fold variation in Mbw. Algorithms based on the slope of the glucose-elimination curve (CL/Vd) in combination with AUCins obtained during the IVGTT showed statistically significant correlations with Mbw, the linearity being r2 = 0.63-0.83. The best algorithms were associated with a 25-75th prediction error ranging from -10% to +10%. Sampling could be shortened to 30-40 min without loss of linearity or precision.ConclusionSimple measures of glucose and insulin kinetics during an IVGTT can predict between 2/3 and 4/5 of the insulin sensitivity.
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14.
  • Hahn, Robert G, et al. (författare)
  • Preoperative insulin resistance reduces complications after hip replacement surgery in non-diabetic patients.
  • 2013
  • Ingår i: BMC Anesthesiology. - : Springer Science and Business Media LLC. - 1471-2253 .- 1471-2253. ; 13:1, s. 39-
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Insulin resistance negatively affects the outcome of surgery in patients with type 2 diabetes. This association is often believed to be present in other patient populations as well, but studies are lacking on the influence of preoperative insulin resistance on the clinical course of surgery in non-diabetic patients.METHODS: Sixty non-diabetic patients with a mean age of 68 years underwent a 75-min intravenous glucose tolerance test (IVGTT) one day before and after elective hip replacement surgery. Patients were regarded to be either insulin resistant (< median insulin sensitivity) or not (> median insulin sensitivity). Hypotensive events occurring in the postoperative care unit and complications in the orthopedic ward were recorded. Fatigue and well-being were assessed via questionnaires.RESULTS: A total of 52 patients were included in the final analysis. Insulin resistance before surgery was associated with a lower risk of arterial hypotension in the postoperative care unit (systolic pressure < 80 mmHg; P < 0.05) and with fewer complications in the orthopedic ward (mean 1.9 versus 1.2 per operation, P < 0.01), particularly with respect to nausea/vomiting (P < 0.04) and arterial hypotension (P < 0.05). Fewer of these patients had more than one complication (23% versus 58%, P < 0.001), while no statistical link between preoperative insulin resistance and fatigue or well-being was evident. Insulin resistance, when measured one day postoperatively, did not correlate with the number of complications.CONCLUSIONS: Preoperative insulin resistance offers some benefit in the postoperative period and early convalescence in non-diabetic patients who undergo hip replacement surgery.
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15.
  • Hahn, Robert, et al. (författare)
  • Plasma volume expansion from the intravenous glucose tolerance test before and after hip replacement surgery
  • 2013
  • Ingår i: Theoretical Biology and Medical Modelling. - : Springer Science and Business Media LLC. - 1742-4682. ; 10:48
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundHyperosmotic glucose is injected intravenously when an intravenous glucose tolerance test (IVGTT) is initiated. The extent and time period of plasma volume expansion that occurs in response to the glucose load has not been studied in the perioperative setting.MethodsTwenty-two non-diabetic patients aged between 57 and 76 years (mean 68) underwent an IVGTT, during which 0.3 g/kg of glucose 30% (1 ml/kg) was injected as a bolus over one minute, one day before and two days after hip replacement surgery. Twelve blood samples were collected over 75 minutes from each patient. The turnover of both the exogenous glucose and the injected fluid volume was calculated by means of mass balance and volume kinetic analysis.ResultsThe IVGTT raised plasma glucose by 9 mmol/L and the plasma volume by 8%. The extracellular fluid volume increased by 320 (SD 60) ml of which 2/3 could be accounted for in the plasma. The half-life of the exogenous glucose averaged 30 minutes before surgery and 36 minutes postoperatively (P < 0.02). The glucose elimination governed 86% of the decay of the plasma volume expansion, which occurred with a half-life of 12 minutes before to 21 minutes after the surgery (median, P < 0.001).ConclusionHyperosmotic glucose translocated intracellular water to the plasma volume rather than to the entire extracellular fluid volume. The preferential re-distribution acts to dilute the plasma concentrations used to quantify insulin sensitivity and ß-cell function from an IVGTT. The greater-than-expected plasma dilution lasted longer after than before surgery.
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16.
  • Hande, Liv Nesse, et al. (författare)
  • Effect of N-3 Polyunsaturated Fatty Acids on Lipid Composition in Familial Hypercholesterolemia : A Randomized Crossover Trial
  • 2022
  • Ingår i: Biomedicines. - : MDPI. - 2227-9059. ; 10:8
  • Tidskriftsartikel (refereegranskat)abstract
    • Individuals with familial hypercholesterolemia (FH) have an increased risk of cardiovascular disease. Treatment is mainly low-density lipoprotein cholesterol (LDL-C) reduction. How omega-3 polyunsaturated fatty acids (n-3 PUFAs) supplements affect lipoproteins in FH subjects is unknown. We hypothesized that a high-dose n-3 PUFA supplement would reduce atherogenic lipoproteins and influence the high-density lipoprotein cholesterol (HDL-C) function. We performed a randomized, double-blinded crossover study with 34 genetically verified FH individuals (18-75 years, clinically stable, statin treatment > 12 months). Treatment was 4 g n-3 PUFAs (1840 mg eicosapentaenoic acid and 1520 mg docosahexaenoic acid daily) or four capsules of olive oil for three months in a crossover design with a washout period of three months. The defined outcomes were changes in triglycerides, lipoproteins, lipoprotein subfractions, apolipoproteins, and HDL-C function. After treatment with n-3 PUFAs, total cholesterol, LDL-C, and triglycerides were reduced compared to placebo (p <= 0.01 for all). Total HDL-C levels were unchanged, but the subfraction of large HDL-C was higher (p <= 0.0001) after n-3 PUFAs than after placebo, and intermediate HDL-C and small HDL-C were reduced after n-3 PUFAs compared to placebo (p = 0.02 and p <= 0.001, respectively). No changes were found in apolipoproteins and HDL-C function. N-3 PUFAs supplements reduced atherogenic lipoproteins in FH subjects, leaving HDL-C function unaffected.
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17.
  • Helmfrid, Ingela, 1964-, et al. (författare)
  • Exposure of metals and PAH through local foods and risk of cancer in a historically contaminated glassworks area
  • 2019
  • Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 131, s. 1-10
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundProduction of crystal glass and colored art glassware have been going on in the south-eastern part of Sweden since the 1700s, at over 100 glassworks and smaller glass blowing facilities, resulting in environmental contamination with mainly arsenic (As), cadmium (Cd), lead (Pb) and polycyclic hydrocarbons (PAH). High levels of metals have been found in soil, and moderately elevated levels in vegetables, mushrooms and berries collected around the glassworks sites compared with reference areas. Food in general, is the major exposure source to metals, such as Cd and Pb, and PAHs. Exposure to these toxic metals and PAH has been associated with a variety of adverse health effects in humans including cancer.ObjectiveThe aim of the present study was to evaluate the occurrence of cancer in a cohort from the contaminated glasswork area in relation to long-term dietary intake of locally produced foods, while taking into account residential, occupational and life styles factors.MethodsThe study population was extracted from a population cohort of 34,266 individuals who, at some time between the years 1979–2004, lived within a 2 km radius of a glassworks or glass landfill. Register information on cancer incidence and questionnaire information on consumption of local foods (reflecting 30 years general eating habits), life-time residence in the area, life style factors and occupational exposure was collected. Furthermore, blood (n = 660) and urine (n = 400) samples were collected in a subsample of the population to explore associations between local food consumption frequencies, biomarker concentrations in blood (Cd, Pb, As) and urine (PAH metabolite 1-OHPy) as well as environmental and lifestyle factors. The concurrent exposure to persistent organic pollutants (POPs) from food was also considered. A case-control study was performed for evaluation of associations between intakes of local food and risk of cancer.ResultsDespite high environmental levels of Cd, Pb and As at glasswork sites and landfills, current metal exposure in the population living in the surrounding areas was similar or only moderately higher in our study population compared to the general population. Reported high consumption of certain local foods was associated with higher Cd and Pb, but not As, concentrations in blood, and 1-OHPy in urine. An increased risk of cancer was associated with smoking, family history of cancer, obesity, and residence in glasswork area before age 5 years. Also, a long-term high consumption of local foods (reflecting 30 years general eating habits), i.e. fish and meat (game, chicken, lamb), was associated with increased risk of various cancer forms.ConclusionsThe associations between consumption of local food and different types of cancer may reflect a higher contaminant exposure in the past, and thus, if consumption of local food contributes to the risk of acquiring cancer, that contribution is probably lower today than before. Furthermore, it cannot be ruled out that other contaminants in the food contribute to the increased cancer risks observed.
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18.
  • Holleboom, Adriaan G, et al. (författare)
  • Heterozygosity for a Loss-of-Function Mutation in GALNT2 Improves Plasma Triglyceride Clearance in Man
  • 2011
  • Ingår i: Cell Metabolism. - : Elsevier. - 1550-4131 .- 1932-7420. ; 14:6, s. 811-8
  • Tidskriftsartikel (refereegranskat)abstract
    • Genome-wide association studies have identified GALNT2 as a candidate gene in lipid metabolism, but it is not known how the encoded enzyme ppGalNAc-T2, which contributes to the initiation of mucin-type O-linked glycosylation, mediates this effect. In two probands with elevated plasma high-density lipoprotein cholesterol and reduced triglycerides, we identified a mutation in GALNT2. It is shown that carriers have improved postprandial triglyceride clearance, which is likely attributable to attenuated glycosylation of apolipoprotein (apo) C-III, as observed in their plasma. This protein inhibits lipoprotein lipase (LPL), which hydrolyses plasma triglycerides. We show that an apoC-III-based peptide is a substrate for ppGalNAc-T2 while its glycosylation by the mutant enzyme is impaired. In addition, neuraminidase treatment of apoC-III which removes the sialic acids from its glycan chain decreases its potential to inhibit LPL. Combined, these data suggest that ppGalNAc-T2 can affect lipid metabolism through apoC-III glycosylation, thereby establishing GALNT2 as a lipid-modifying gene.
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19.
  • Jamal, Sophie A., et al. (författare)
  • Effects of Denosumab on Fracture and Bone Mineral Density by Level of Kidney Function
  • 2011
  • Ingår i: Journal of Bone and Mineral Research. - : Wiley. - 0884-0431 .- 1523-4681. ; 26:8, s. 1829-1835
  • Tidskriftsartikel (refereegranskat)abstract
    • The incidences of osteoporosis and chronic kidney disease (CKD) both increase with increasing age, yet there is a paucity of data on treatments for osteoporosis in the setting of impaired kidney function. We examined the efficacy and safety of denosumab (DMAb) among subjects participating in the Fracture Reduction Evaluation of Denosumab in Osteoporosis Every 6Months (FREEDOM) Study. We estimated creatinine clearance (eGFR) using Cockcroft-Gault and classified levels of kidney function using the modified National Kidney Foundation classification of CKD. We examined incident fracture rates; changes in bone mineral density (BMD), serum calcium, and creatinine; and the incidence of adverse events after 36 months of follow-up in subjects receiving DMAb or placebo, stratified by level of kidney function. We used a subgroup interaction term to determine if there were differences in treatment effect by eGFR. Most (93%) women were white, and the mean age was 72.3 +/- 5.2 years; 73 women had an eGFR of 15 to 29mL/min; 2817, between 30 to 59mL/min; 4069, between 60 to 89mL/min, and 842 had an eGFR of 90mL/min or greater. None had stage 5 CKD. Fracture risk reduction and changes in BMD at all sites were in favor of DMAb. The test for treatment by subgroup interaction was not statistically significant, indicating that treatment efficacy did not differ by kidney function. Changes in creatinine and calcium and the incidence of adverse events were similar between groups and did not differ by level of kidney function. It is concluded that DMAb is effective at reducing fracture risk and is not associated with an increase in adverse events among patients with impaired kidney function.
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20.
  • Jiang, Zheshun, et al. (författare)
  • Hexavalent chromium still a concern in Sweden : Evidence from a cross-sectional study within the SafeChrom project
  • 2024
  • Ingår i: International journal of hygiene and environmental health. - : Elsevier. - 1438-4639 .- 1618-131X. ; 256
  • Tidskriftsartikel (refereegranskat)abstract
    • ObjectivesHexavalent chromium (Cr(VI)) is classified as a human carcinogen. Occupational Cr(VI) exposure can occur during different work processes, but the current exposure to Cr(VI) at Swedish workplaces is unknown.MethodsThis cross-sectional study (SafeChrom) recruited non-smoking men and women from 14 companies with potential Cr(VI) exposure (n = 113) and controls from 6 companies without Cr(VI) exposure (n = 72). Inhalable Cr(VI) was measured by personal air sampling (outside of respiratory protection) in exposed workers. Total Cr was measured in urine (pre- and post-shift, density-adjusted) and red blood cells (RBC) (reflecting Cr(VI)) in exposed workers and controls. The Bayesian tool Expostats was used to assess risk and evaluate occupational exposure limit (OEL) compliance.ResultsThe exposed workers performed processing of metal products, steel production, welding, plating, and various chemical processes. The geometric mean concentration of inhalable Cr(VI) in exposed workers was 0.15 μg/m3 (95% confidence interval: 0.11–0.21). Eight of the 113 exposed workers (7%) exceeded the Swedish OEL of 5 μg/m3, and the Bayesian analysis estimated the share of OEL exceedances up to 19.6% for stainless steel welders. Median post-shift urinary (0.60 μg/L, 5th-95th percentile 0.10–3.20) and RBC concentrations (0.73 μg/L, 0.51–2.33) of Cr were significantly higher in the exposed group compared with the controls (urinary 0.10 μg/L, 0.06–0.56 and RBC 0.53 μg/L, 0.42–0.72). Inhalable Cr(VI) correlated with urinary Cr (rS = 0.64) and RBC-Cr (rS = 0.53). Workers within steel production showed the highest concentrations of inhalable, urinary and RBC Cr. Workers with inferred non-acceptable local exhaustion ventilation showed significantly higher inhalable Cr(VI), urinary and RBC Cr concentrations compared with those with inferred acceptable ventilation. Furthermore, workers with inferred correct use of respiratory protection were exposed to significantly higher concentrations of Cr(VI) in air and had higher levels of Cr in urine and RBC than those assessed with incorrect or no use. Based on the Swedish job-exposure-matrix, approximately 17 900 workers were estimated to be occupationally exposed to Cr(VI) today.ConclusionsOur study demonstrates that some workers in Sweden are exposed to high levels of the non-threshold carcinogen Cr(VI). Employers and workers seem aware of Cr(VI) exposure, but more efficient exposure control strategies are required. National strategies aligned with the European strategies are needed in order to eliminate this cause of occupational cancer.
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21.
  • Karlsson, Hanna L., et al. (författare)
  • Health hazards of particles in additive manufacturing : a cross-disciplinary study on reactivity, toxicity and occupational exposure to two nickel-based alloys
  • 2023
  • Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322. ; 13:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The increasing use of additive manufacturing (AM) techniques (e.g., 3D-printing) offers many advantages but at the same time presents some challenges. One concern is the possible exposure and health risk related to metal containing particles of different sizes. Using the nickel-based alloys Hastelloy X (HX) and Inconel 939 (IN939) as a case, the aim of this cross-disciplinary study was to increase the understanding on possible health hazards and exposure. This was done by performing in-depth characterization of virgin, reused and condensate powders, testing in vitro toxicity (cytotoxicity, genotoxicity, oxidative stress), and measuring occupational airborne exposure. The results showed limited metal release from both HX and IN939, and slightly different surface composition of reused compared to virgin powders. No or small effects on the cultured lung cells were observed when tested up to 100 µg/mL. Particle background levels in the printing facilities were generally low, but high transient peaks were observed in relation to sieving. Furthermore, during post processing with grinding, high levels of nanoparticles (> 100,000 particles/cm3) were noted. Urine metal levels in AM operators did not exceed biomonitoring action limits. Future studies should focus on understanding the toxicity of the nanoparticles formed during printing and post-processing.
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22.
  • Karlsson, Helen, 1961-, et al. (författare)
  • Two-dimensional gel electrophoresis and mass spectrometry in studies of nanoparticle-protein interactions
  • 2012
  • Ingår i: Gel electrophoresis-Advanced Techniques. - Rijeka, Croatia : In Tech. - 9789535104575 ; , s. 327-358
  • Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
    • Over the years a number of epidemiological studies have shown that PM from combustion sources such as motor vehicles contributes to respiratory and cardiovascular morbidity and mortality.Especially so do the ultra-fine particles (UFPs) with a diameter less than 0.1 micrometer.UFPs from combustion engines are capable to translocate over the alveolar–capillary barrier.  When nano-sized PM (nanoparticles, NP), which are small enough to enter the blood stream, do so they are likely to interact with plasma proteins and this protein-NP interaction will probably affect the fate of and the effects caused by the NPs in the human body. Here, by using a proteomic approach, we present results showing that several proteins indeed are associated to NPs that have in vitro been introduced to human blood plasma.
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23.
  • Kilbo Edlund, Karl, et al. (författare)
  • Long-term ambient air pollution and coronary atherosclerosis : results from the Swedish SCAPIS study
  • 2024
  • Ingår i: Atherosclerosis. - : Elsevier. - 0021-9150 .- 1879-1484.
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and aims: Despite firm evidence for an association between long-term ambient air pollution exposure and cardiovascular morbidity and mortality, results from epidemiological studies on the association between air pollution exposure and atherosclerosis have not been consistent. We investigated associations between long-term low-level air pollution exposure and coronary atherosclerosis.Methods: We performed a cross-sectional analysis in the large Swedish CArdioPulmonary bioImaging Study (SCAPIS, n = 30 154), a random general population sample. Concentrations of total and locally emitted particulate matter <2.5 μm (PM2.5), <10 μm (PM10), and nitrogen oxides (NOx) at the residential address were modelled using high-resolution dispersion models. We estimated associations between air pollution exposures and segment involvement score (SIS), coronary artery calcification score (CACS), number of non-calcified plaques (NCP), and number of significant stenoses, using ordinal regression models extensively adjusted for potential confounders.Results: Median 10-year average PM2.5 exposure was 6.2 μg/m3 (range 3.5–13.4 μg/m3). 51 % of participants were women and 51 % were never-smokers. None of the assessed pollutants were associated with a higher SIS or CACS. Exposure to PM2.5 was associated with NCP (adjusted OR 1.34, 95 % CI 1.13, 1.58, per 2.05 μg/m3). Associations with significant stenoses were inconsistent.Conclusions: In this large, middle-aged general population sample with low exposure levels, air pollution was not associated with measures of total burden of coronary atherosclerosis. However, PM2.5 appeared to be associated with a higher prevalence of non-calcified plaques. The results suggest that increased risk of early-stage atherosclerosis or rupture, but not increased total atherosclerotic burden, may be a pathway for long-term air pollution effects on cardiovascular disease.
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24.
  • Kilbo Edlund, Karl, et al. (författare)
  • Long-term ambient air pollution and coronary atherosclerosis: Results from the Swedish SCAPIS study.
  • 2024
  • Ingår i: Atherosclerosis. - 1879-1484.
  • Tidskriftsartikel (refereegranskat)abstract
    • Despite firm evidence for an association between long-term ambient air pollution exposure and cardiovascular morbidity and mortality, results from epidemiological studies on the association between air pollution exposure and atherosclerosis have not been consistent. We investigated associations between long-term low-level air pollution exposure and coronary atherosclerosis.We performed a cross-sectional analysis in the large Swedish CArdioPulmonary bioImaging Study (SCAPIS, n=30154), a random general population sample. Concentrations of total and locally emitted particulate matter <2.5μm (PM2.5), <10μm (PM10), and nitrogen oxides (NOx) at the residential address were modelled using high-resolution dispersion models. We estimated associations between air pollution exposures and segment involvement score (SIS), coronary artery calcification score (CACS), number of non-calcified plaques (NCP), and number of significant stenoses, using ordinal regression models extensively adjusted for potential confounders.Median 10-year average PM2.5 exposure was 6.2μg/m3 (range 3.5-13.4μg/m3). 51% of participants were women and 51% were never-smokers. None of the assessed pollutants were associated with a higher SIS or CACS. Exposure to PM2.5 was associated with NCP (adjusted OR 1.34, 95% CI 1.13, 1.58, per 2.05μg/m3). Associations with significant stenoses were inconsistent.In this large, middle-aged general population sample with low exposure levels, air pollution was not associated with measures of total burden of coronary atherosclerosis. However, PM2.5 appeared to be associated with a higher prevalence of non-calcified plaques. The results suggest that increased risk of early-stage atherosclerosis or rupture, but not increased total atherosclerotic burden, may be a pathway for long-term air pollution effects on cardiovascular disease.
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25.
  • Kjellmo, Christian Abendstein, et al. (författare)
  • Bariatric surgery improves lipoprotein profile in morbidly obese patients by reducing LDL cholesterol, apoB, and SAA/PON1 ratio, increasing HDL cholesterol, but has no effect on cholesterol efflux capacity
  • 2018
  • Ingår i: Journal of Clinical Lipidology. - : ELSEVIER SCIENCE INC. - 1933-2874 .- 1876-4789. ; 12:1, s. 193-202
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Bariatric surgery has been shown to reduce cardiovascular events and cause specific mortality for coronary artery disease in obese patients. Lipoprotein biomarkers relating to low-density lipoprotein (LDL), high-density lipoprotein (HDL), their subfractions, and macrophage cholesterol efflux have all been hypothesized to be of value in cardiovascular risk assessment. OBJECTIVES: The objective of this study was to examine the effect of a lifestyle intervention followed by bariatric surgery on the lipid profile of morbidly obese patients. METHODS: Thirty-four morbidly obese patients were evaluated before and after lifestyle changes and then 1 year after bariatric surgery. They were compared with 17 lean subjects. Several lipoprotein metrics, serum amyloid A (SAA), serum paraoxonase-1 (PON1), and macrophage cholesterol efflux capacity (CEC) were assessed. RESULTS: Average weight loss after the lifestyle intervention was 10.5% and 1 year after bariatric surgery was 33.9%. The lifestyle intervention significantly decreased triglycerides (TGs; 28.7 mg/dL, P amp;lt; .05), LDL cholesterol (LDL-C; 32.3 mg/dL, P amp;lt; .0001), and apolipoprotein B (apoB; 62.9 mu g/mL, P amp;lt; .001). Bariatric surgery further reduced TGs (-36.7 mg/dL, P amp;lt; .05), increased HDL cholesterol (+12 mg/dL, P amp;lt; .0001), and reductions in LDL-C and apoB were sustained. Bariatric surgery reduced large, buoyant LDL (P amp;lt; .0001), but had no effect on the small, dense LDL.The large HDL subfractions increased (P amp;lt; .0001), but there was no effect on the smaller HDL sub fractions. The ratio for SAA/PON1 was reduced after the lifestyle intervention (P amp;lt; .01) and further reduced after bariatric surgery (P amp;lt; .0001). Neither the lifestyle intervention nor bariatric surgery had any effect on CEC. CONCLUSIONS: Lifestyle intervention followed by bariatric surgery in 34 morbidly obese patients showed favorable effects on TGs, LDL-C, and apoB. HDL cholesterol and apoA1 was increased, apoB/apoA1 ratio as well as SAA/PON1 ratio reduced, but bariatric surgery did not influence CEC. (C) 2017 National Lipid Association. All rights reserved.
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26.
  • Kotova, Natalia, et al. (författare)
  • Nätverk vid upptäckt av befolkningsexponering för farliga kemiska ämnen : en sammanställning av kompetens och laboratorieverksamhet bland regionala Arbets- och miljömedicinska enheter vid upptäckt av befolkningsexponering för farliga ämnen av kemiskt ursprung där livsmedel och dricksvatten kan vara en potentiell källa
  • 2017
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • I Livsmedelsverkets beredskapsarbete ingår att göra uppskattningar av vilka nivåer av farliga ämnen som konsumenterna får i sig via livsmedel och att tidigt upptäcka exponering som kan resultera i skadliga hälsoeffekter. Detta arbete innebär att övervakningen behöver förbättras gällande risker för kemisk exponering. I händelse av kemisk exponering av befolkningen via livsmedel eller vatten, beroende på olyckor eller antagonistiska händelser, behövs en väl samordnad kedja inkluderande bl.a. operativa aktörer samt centrala och regionala myndigheter.Denna rapport är ett resultat av krisberedskapsprojektet Nätverk vid upptäckt av befolkningsexponering för farliga kemiska ämnen som finansierats med 2:4-anslag från MSB. Projektets syfte är att bilda ett nätverk mellan olika aktörer för att skapa förutsättningar för ett bättre utnyttjande av landets samlade kapacitet och kompetens avseende provtagnings- och laboratorieanalys i avsikt att identifiera farliga kemiska ämnen i prover från människa. Nätverket är till för att skapa en effektivare beredskap vid allvarliga händelser med kemiska ämnen och/eller för övervakning av exponering för kemiska ämnen hos den svenska befolkningen.Projektet fokuserade på att inventera och förbättra kunskapsläget och laboratorieberedskap för provtagning och analys av prover från människa vid upptäckt av befolkningsexponering för farliga ämnen. Detta gäller i livsmedel och dricksvatten då ämnen av kemiskt ursprung kan vara en potentiell farlig källa. Projektet skapade ett nätverk mellan myndigheter och regionala Arbets- och miljömedicinska (AMM) enheter för att skapa förutsättningar för ett bättre utnyttjande av landets samlade kapacitet, kompetens och laboratorier inom AMM-verksamheten. För att stärka såväl regional som nationell krisberedskap när det gäller hanteringen av oönskade händelser så har projektets alla AMM-enheter i Sverige kartlagt kompetens och laboratoriekapacitet samt testat förmågan att arbeta i fält med provtagning och efterhantering av prover.Målgruppen för rapporten är de som arbetar med identifiering och riskvärdering av farliga ämnen med kemiskt ursprung i befolkningen, både vid kris och i vardagen. Nätverkets arbete resulterade bl.a. i de manualer som används vid exponering för olika typer av CBRNE-ämnen dvs. inte enbart kemiska (C-ämnen), men också biologiska (B-ämnen), radiologiska (R-ämnen), nukleära (N-ämnen) och explosiva (E-ämnen). Projektet har drivits av Livsmedelsverket i ett nära samarbete med regionala AMM-enheter och Totalförsvarets Forskningsinstitut (FOI) samt i samverkan med Folkhälsomyndigheten, Naturvårdsverket, Socialstyrelsen, Kemikalieinspektionen och Karolinska Institutet.
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27.
  • Lappegård, Knut Tore, et al. (författare)
  • Lipoprotein apheresis affects lipoprotein particle subclasses more efficiently compared to the PCSK9 inhibitor evolocumab, a pilot study.
  • 2018
  • Ingår i: Transfusion and apheresis science. - : Elsevier BV. - 1473-0502 .- 1878-1683. ; 57:1, s. 91-96
  • Tidskriftsartikel (refereegranskat)abstract
    • Lipoprotein apheresis and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are last therapeutic resorts in patients with familial hypercholesterolemia (FH). We explored changes in lipoprotein subclasses and high-density lipoprotein (HDL) function when changing treatment from lipoprotein apheresis to PCSK9 inhibition. We measured the levels of low-density lipoprotein (LDL) and HDL particle subclasses, serum amyloid A1 (SAA1), paraoxonase-1 (PON1) activity and cholesterol efflux capacity (CEC) in three heterozygous FH patients. Concentrations of all LDL particle subclasses were reduced during apheresis (large 68.0 ± 17.5 to 16.3 ± 2.1 mg/dL, (p = 0.03), intermediate 38.3 ± 0.6 to 5.0 ± 3.5 mg/dL (p = 0.004) and small 5.0 ± 2.6 to 0.2 ± 0.1 mg/dL (p = 0.08)). There were non-significant reductions in the LDL subclasses during evolocumab treatment. There were non-significant reductions in subclasses of HDL particles during apheresis, and no changes during evolocumab treatment. CEC was unchanged throughout the study, while the SAA1/PON1 ratio was unchanged during apheresis but decreased during evolocumab treatment. In conclusion, there were significant reductions in large and intermediate size LDL particles during apheresis, and a non-significant reduction in small LDL particles. There were only non-significant reductions in the LDL subclasses during evolocumab treatment.
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28.
  • Levels, Johannes HM, et al. (författare)
  • High-density Lipoprotein proteome dynamics in human endotoxemia
  • 2011
  • Ingår i: Proteome Science. - : BiOMed Central. - 1477-5956. ; 9:34
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: A large variety of proteins involved in inflammation, coagulation, lipid-oxidation and lipid metabolism have been associated with high-density lipoprotein (HDL) and it is anticipated that changes in the HDL proteome have implications for the multiple functions of HDL. Here, SELDI-TOF mass spectrometry (MS) was used to study the dynamic changes of HDL protein composition in a human experimental low-dose endotoxemia model. Ten healthy men with low HDL cholesterol (0.7+/-0.1 mmol/L) and 10 men with high HDL cholesterol levels (1.9+/-0.4mmol/L) were challenged with endotoxin (LPS) intravenously (1ng/kg bodyweight). We previously showed that subjects with low HDL cholesterol are more susceptible to an inflammatory challenge. The current study tested the hypothesis that this discrepancy may be related to differences in the HDL proteome.Results: Plasma drawn at 7 time-points over a 24 hour time period after LPS challenge was used for direct capture of HDL using antibodies against apolipoprotein A-I followed by subsequent SELDI-TOF MS profiling. Upon LPS administration, profound changes in 21 markers (adjusted p-value<0.05) were observed in the proteome in both study groups. These changes were observed 1 hour after LPS infusion and sustained up to 24 hours, but unexpectedly were not different between the 2 study groups. Hierarchical clustering of the protein spectra at all time points of all individuals revealed 3 distinct clusters, which were largely independent of baseline HDL cholesterol levels but correlated with paraoxonase 1 activity. The acute phase protein serum amyloid A-1/2 (SAA-1/2) was clearly upregulated after LPS infusion in both groups and comprised both native and N-terminal truncated variants that were identified by two-dimensional gel electrophoresis and mass spectrometry. Individuals of one of the clusters were distinguished by a lower SAA-1/2 response after LPS challenge and a delayed time-response of the truncated variants.Conclusions: This study shows that the semi-quantitative differences in the HDL proteome as assessed by SELDI-TOF MS cannot explain why subjects with low HDL cholesterol are more susceptible to a challenge with LPS than those with high HDL cholesterol. Instead the results indicate that hierarchical clustering could be useful to predict HDL functionality in acute phase responses towards LPS.
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29.
  • Lewerin, Catharina, 1961, et al. (författare)
  • Low holotranscobalamin and cobalamins predict incident fractures in elderly men: the MrOS Sweden.
  • 2014
  • Ingår i: Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA. - : Springer Science and Business Media LLC. - 1433-2965 .- 0937-941X. ; 25:1, s. 131-140
  • Tidskriftsartikel (refereegranskat)abstract
    • In a population-based study on cobalamin status and incident fractures in elderly men (n=790) with an average follow-up of 5.9years, we found that low levels of metabolically active and total cobalamins predict incident fractures, independently of body mass index (BMI), bone mineral density (BMD), plasma total homocysteine (tHcy), and cystatin C.
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30.
  • Liang, Wenzhao, et al. (författare)
  • Distinctive proteomic profiles among different regions of human carotid plaques in men and women
  • 2016
  • Ingår i: Scientific Reports. - : NATURE PUBLISHING GROUP. - 2045-2322. ; 6:26231
  • Tidskriftsartikel (refereegranskat)abstract
    • The heterogeneity of atherosclerotic tissue has limited comprehension in proteomic and metabolomic analyses. To elucidate the functional implications, and differences between genders, of atherosclerotic lesion formation we investigated protein profiles from different regions of human carotid atherosclerotic arteries; internal control, fatty streak, plaque shoulder, plaque centre, and fibrous cap. Proteomic analysis was performed using 2-DE with MALDI-TOF, with validation using nLC-MS/MS. Protein mapping of 2-DE identified 52 unique proteins, including 15 previously unmapped proteins, of which 41 proteins were confirmed by nLC-MS/MS analysis. Expression levels of 18 proteins were significantly altered in plaque regions compared to the internal control region. Nine proteins showed site-specific alterations, irrespective of gender, with clear associations to extracellular matrix remodelling. Five proteins display gender-specific alterations with 2-DE, with two alterations validated by nLC-MS/MS. Gender differences in ferritin light chain and transthyretin were validated using both techniques. Validation of immunohistochemistry confirmed significantly higher levels of ferritin in plaques from male patients. Proteomic analysis of different plaque regions has reduced the effects of plaque heterogeneity, and significant differences in protein expression are determined in specific regions and between genders. These proteomes have functional implications in plaque progression and are of importance in understanding gender differences in atherosclerosis.
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31.
  • Lindahl, Katarina, et al. (författare)
  • Genotype-Phenotype Correlations, Response to Bisphosphonate Treatment and Pharmaco-genetics in 150 Swedish Families with Osteogenesis Imperfecta (Type I, IV and III)
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • Introduction: Osteogenesis imperfecta (OI) is a rare heterogeneous disorder leading to bone fragility, spanning from mild to lethal in severity. Over 1500 mutations have been described in collagen type I, encoded by COL1A1 and COL1A2. Bisphosphonate treatment is standard of care and published studies clearly show beneficial effects on Bone Mineral Density (BMD) and vertebral geometry. However, information on BMD increase in relation to age and BMD at onset is limited and there are few studies on influence of mutation type on treatment response. In this study Swedish patients with OI types I, IV and III were investigated with respect to genotype-phenotype correlations, BMD response on bisphosphonate treatment, and pharmaco-genetics.Materials and Methods: 150 families (202 individuals) with OI participated: 137 type I, 40 type IV and 25 type III. Data on phenotype and bisphosphonate treatment were collected and sequencing of COL1A1 and COL1A2 performed.Results: In 119 families a mutation was detected; in COL1A1 52 quantitative and 35 qualitative mutations were found and in COL1A2 32 qualitative mutations were found. Several unrelated individuals were found to harbor mutations with the same positions and substitutions and only 15 qualitative mutations were novel, supporting the idea of mutational hotspots. Genotype-phenotype analysis confirmed that mutations situated in the a1-chain are associated with a more severe phenotype, blue sclerae are strongly associated with COL1A1 null alleles, qualitative mutations are associated with DI, and for qualitative mutations position relative to N- and C-terminal is correlated to phenotype. A few novel mutations with unconventional locations were found.Bisphosphonate treatment response was inversely correlated with age (p=<0.0001) and lumbar spine BMD at onset (p=0.006). Mutations associated with a more severe phenotype had an improved response to treatment when analyzing 2-year delta lumbar spine Z-score values; mutations in COL1A1 vs. COL1A2 (p=0.03), qualitative mutations in COL1A1 vs. COL1A2 (p=0.006), serine substitutions in COL1A1 vs. COL1A2 (p=0.007) and qualitative vs. qualitative mutations in COL1A1 (p=0.02) all exhibited this pattern. Bisphosphonate response was not correlated to either OI type or gender.Conclusions: The genotype-phenotype correlations described here confirm previous reports of influence of chain affected, intrachain location, and mutation type on phenotype. BMD response to bisphosphonate treatment is inversely related to age and BMD at onset. Pharmaco-genetic analyses show an increased response to bisphosphonate treatment for more severe mutations types. This effect is attenuated over time.
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32.
  • Ljunggren, L, et al. (författare)
  • Weaning of juvenile pikeperch (Stizostedion lucioperca (L.)) and perch (Perca fluviatilis (L.)) to formulated feed.
  • 2003
  • Ingår i: Aquaculture Research. - 1355-557X. ; 34:4, s. 281-287
  • Tidskriftsartikel (refereegranskat)abstract
    • Weaning success of pond-cultured pikeperch and wild-caught perch (mean length 51 and 48 mm respectively) was evaluated using different weaning techniques and different formulated feeds. Juveniles that were fed formulated feed grew as well as or better than juveniles that were weaned successively using zooplankton or yolk. Four different formulated feeds (agglomerated marine larvae feed, marine larvae feed, trout feed and a semi-moist feed) were evaluated regarding specific growth rate (SGR), condition factor and a subjective stomach fullness estimate. The agglomerated marine larvae feed gave significantly better weaning performance than the other feeds regarding all parameters (SGR = 7.3% day(-1) and 3.4% day(-1) for pikeperch and perch respectively).
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33.
  • Ljunggren, Stefan A, et al. (författare)
  • Altered heart proteome in fructose-fed Fisher 344 rats exposed to bisphenol A
  • 2016
  • Ingår i: Toxicology. - : Elsevier BV. - 0300-483X .- 1879-3185. ; 347-349, s. 6-16
  • Tidskriftsartikel (refereegranskat)abstract
    • Bisphenol A (BPA), is an artificial estrogen initially produced for medical purposes but is today widely used in polycarbonate plastics and epoxy resins. Exposure-related reproductive disorders have been found, but recently it has also been suggested that BPA may be involved in obesity, diabetes, myocardial hypertrophy and myocardial infarction in humans. To mimic a modern lifestyle, female rats were fed with fructose or fructose plus BPA (0.25 mg/L drinking water). The myocardial left ventricle proteome of water controls, fructose-fed and fructose-fed plus BPA supplemented rats was explored. The proteome was investigated using nano-liquid chromatography tandem mass spectrometry and two-dimensional gel electrophoresis followed by matrix assisted laser desorption/ionization mass spectrometry identification. In total, 41 proteins were significantly altered by BPA exposure compared to water or fructose controls. Principal component analysis and cellular process enrichment analysis of altered proteins suggested increased fatty acid transport and oxidation, increased ROS generation and altered structural integrity of the myocardial left ventricle in the fructose-fed BPA-exposed rats, indicating unfavorable effects on the myocardium. In conclusion, BPA exposure in the rats induces major alterations in the myocardial proteome.
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34.
  • Ljunggren, Stefan A, et al. (författare)
  • Lipoprotein profiles in human heterozygote carriers of a functional mutation P297S in scavenger receptor class B1.
  • 2015
  • Ingår i: Biochimica et Biophysica Acta - Molecular and Cell Biology of Lipids. - : Elsevier. - 1388-1981 .- 1879-2618. ; 1851:12, s. 1587-1595
  • Tidskriftsartikel (refereegranskat)abstract
    • The scavenger receptor class B type 1 (SR-B1) is an important HDL receptor involved in cholesterol uptake and efflux, but its physiological role in human lipoprotein metabolism is not fully understood. Heterozygous carriers of the SR-B1P297S mutation are characterized by increased HDL cholesterol levels, impaired cholesterol efflux from macrophages and attenuated adrenal function. Here, the composition and function of lipoproteins were studied in SR-B1P297S heterozygotes.Lipoproteins from six SR-B1P297S carriers and six family controls were investigated. HDL and LDL/VLDL were isolated by ultracentrifugation and proteins were separated by two-dimensional gel electrophoresis and identified by mass spectrometry. HDL antioxidant properties, paraoxonase 1 activities, apoA-I methionine oxidations and HDL cholesterol efflux capacity were assessed.Multivariate modeling separated carriers from controls based on lipoprotein composition. Protein analyses showed a significant enrichment of apoE in LDL/VLDL and of apoL-1 in HDL from heterozygotes compared to controls. The relative distribution of plasma apoE was increased in LDL and in lipid-free form. There were no significant differences in paraoxonase 1 activities, HDL antioxidant properties or HDL cholesterol efflux capacity but heterozygotes showed a significant increase of oxidized methionines in apoA-I.The SR-B1P297S mutation affects both HDL and LDL/VLDL protein compositions. The increase of apoE in carriers suggests a compensatory mechanism for attenuated SR-B1 mediated cholesterol uptake by HDL. Increased methionine oxidation may affect HDL function by reducing apoA-I binding to its targets. The results illustrate the complexity of lipoprotein metabolism that has to be taken into account in future therapeutic strategies aiming at targeting SR-B1.
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35.
  • Ljunggren, Stefan A, et al. (författare)
  • Persistent organic pollutants distribution in lipoprotein fractions in relation to cardiovascular disease and cancer
  • 2014
  • Ingår i: Environment International. - Kidlington : Pergamon-Elsevier Science Ltd. - 0160-4120 .- 1873-6750. ; 65, s. 93-99
  • Tidskriftsartikel (refereegranskat)abstract
    • Persistent organic pollutants (POPS) are lipophilic environmental toxins that have been associated with cardiovascular disease (CVD) and cancer. The aim of this study was to investigate the concentrations of POPs in human high and low/very low-density lipoproteins (HDL and LDL/VLDL) and the possible association with CVD and cancer occurrence in individuals living in a contaminated area. Lipoproteins from 28 individuals (7 healthy controls, 8 subjects with cancer, 13 subjects with CVD) were isolated and the fraction-specific concentration of 20 different POPs was analyzed by high resolution gas chromatography/high resolution mass spectrometry. The activity of Paraoxonase 1 (PON1), an anti-oxidant in HDL, was determined in plasma of these 28 subjects and additional 50 subjects from the same area excluding diseases other than cancer or CVD. Fourteen polychlorinated biphenyls (PCBs) and three organochlorine pesticides were detected, and especially highly chlorinated PCBs were enriched in lipoproteins. Significantly higher concentrations of POPs were found among individuals with CVD or cancer compared to controls. Principal component analyses showed that POP concentrations in HDL were more associated with CVD, while POP concentrations in LDL/VLDL were more associated with cancer. PON1 activity was negatively correlated to sumPCB and a co-variation between decreased arylesterase-activity, increased PCB concentrations and CVD was found. This study shows that POPs are present in lipoproteins and were more abundant in individuals with CVD or cancer compared to healthy controls. The results also indicate that PCB exposure is accompanied by reduced PON1 activity that could impair the HDL function to protect against oxidation. (C) 2014 Elsevier Ltd. All rights reserved.
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36.
  • Ljunggren, Stefan, et al. (författare)
  • Accuracy and precision of commonly used methods for quantifying surgery-induced insulin resistance : Prospective observational study
  • 2014
  • Ingår i: European Journal of Anaesthesiology. - : Lippincott Williams & Wilkins. - 0265-0215 .- 1365-2346. ; 31:2, s. 110-116
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Insulin resistance develops in the perioperative setting and has an adverse influence on postoperative recovery and well-being.OBJECTIVES: To evaluate the effectiveness of commonly used methods for quantifying surgery-induced insulin resistance.DESIGN: Prospective observational study.SETTING: Surgery department and orthopaedic ward at two regional hospitals.PATIENTS: Twenty-two patients (mean age 68 years) scheduled for elective hip replacement.INTERVENTIONS: A short seven-sample intravenous glucose tolerance test (IVGTT) followed by a euglycaemic hyperinsulinaemic glucose clamp 1 day before and 2 days after the surgery.MAIN OUTCOME MEASURES: Insulin resistance shown by dynamic tests (the IVGTT and the glucose clamp) were compared to static tests [the quantitative insulin sensitivity check index (QUICKI) and the homeostatic model assessment-insulin resistance (HOMA-IR)], which use only the plasma glucose and insulin concentrations at baseline.RESULTS: The linear correlation coefficients for the relationship between insulin resistance as obtained with the glucose clamp and the other methods before or after surgery were 0.76 (IVGTT), 0.58 (QUICKI) and -0.65 (HOMA). The prediction errors (precision) averaged 18, 29 and 31%, respectively. Surgery-induced insulin resistance amounted to 45% (glucose clamp), 26% (IVGTT), 4% (QUICKI) and 3% (HOMA).CONCLUSION: Despite reasonably good linear correlations, the static tests grossly underestimated the degree of insulin resistance that developed in response to surgery.
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37.
  • Ljunggren, Stefan, et al. (författare)
  • Alterations in high-density lipoprotein proteome and function associated with persistent organic pollutants
  • 2017
  • Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 98, s. 204-211
  • Tidskriftsartikel (refereegranskat)abstract
    • There is a growing body of evidence that persistent organic pollutants (POPs) may increase the risk for cardiovascular disease (CVD), but the mechanisms remain unclear. High- density lipoprotein (HDL) acts protective against CVD by different processes, andwe have earlier found that HDL from subjects with CVD contains higher levels of POPs than healthy controls. In the present study, we have expanded analyses on the same individuals living in a contaminated community and investigated the relationship between the HDL POP levels and protein composition/ function. HDL from17 subjectswas isolated by ultracentrifugation. HDL protein composition, using nanoliquid chromatography tandemmass spectrometry, and antioxidant activity were analyzed. The associations of 16 POPs, including polychlorinated biphenyls (PCBs) and organochlorine pesticides, with HDL proteins/functionswere investigated by partial least square and multiple linear regression analysis. Proteomic analyses identified 118 HDL proteins, of which ten were significantly (p b 0.05) and positively associated with the combined level of POPs or with highly chlorinated PCB congeners. Among these, cholesteryl ester transfer protein and phospholipid transfer protein, as well as the inflammatory marker serum amyloid A, were found. The serum paraoxonase/arylesterase 1 activity was inversely associated with POPs. Pathway analysis demonstrated that up- regulated proteinswere associatedwith biological processes involving lipoproteinmetabolism, while down- regulated proteinswere associatedwith processes such as negative regulation of proteinases, acute phase response, platelet degranulation, and complement activation. These results indicate an association between POP levels, especially highly chlorinated PCBs, and HDL protein alterations that may result in a less functional particle. Further studies are needed to determine causality and the importance of other environmental factors. Nevertheless, this study provides a first insight into a possible link between exposure to POPs and risk of CVD.
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38.
  • Ljunggren, Stefan, et al. (författare)
  • ApoA-I mutations, L202P and K131del, in HDL from heterozygotes with low HDL-C
  • 2014
  • Ingår i: PROTEOMICS - Clinical Applications. - : Wiley-Blackwell. - 1862-8346 .- 1862-8354. ; 8:3-4, s. 241-250
  • Tidskriftsartikel (refereegranskat)abstract
    • PURPOSE: Mutations in apolipoprotein A-I (apoA-I) may affect plasma high-density lipoprotein (HDL) cholesterol levels and the risk for cardiovascular disease but little is known about the presence and effects of circulating apoA-I variants. This study investigates whether the apoA-I mutations, apoA-I(L202P) and apoA-I(K131del) , are present on plasma HDL particles derived from heterozygote carriers and whether this is associated to changes in HDL protein composition.EXPERIMENTAL DESIGN: Plasma HDL of heterozygotes for either apoA-I(L202P) or apoA-I(K131del) and family controls was isolated using ultracentrifugation. HDL proteins were separated by 2DE and analyzed by MS.RESULTS: ApoA-I peptides containing apoA-I(L202P) or apoA-I(K131del) were identified in HDL from heterozygotes. The apoA-I(L202P) mutant peptide was less abundant than wild-type peptide while the apoA-I(K131del) mutant peptide was more abundant than wild-type peptide in the heterozygotes. Two-dimensional gel electrophoresis analyses indicated that, compared to controls, HDL in apoA-I(L202P) carriers contained less apoE and more zinc-α-2-glycoprotein while HDL from the apoA-I(K131del) heterozygotes contained more alpha-1-antitrypsin and transthyretin.CONCLUSIONS AND CLINICAL RELEVANCE: Both apoA-I(L202P) and apoA-I(K131del) were identified in HDL. In heterozygotes, these mutations have markedly differential effects on the concentration of wild-type apoA-I in the circulation, as well as the HDL proteome, both of which might affect the clinical phenotype encountered in the heterozygous carriers.
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39.
  • Ljunggren, Stefan, et al. (författare)
  • Biomonitoring of Metal Exposure During Additive Manufacturing (3D Printing)
  • 2019
  • Ingår i: SH@W Safety and Health at Work. - : Elsevier. - 2093-7911 .- 2093-7997. ; 10:4, s. 518-526
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Additive manufacturing (AM) is a rapidly expanding new technology involving challenges to occupational health. Here, metal exposure in an AM facility with large-scale metallic component production was investigated during two consecutive years with preventive actions in between.Methods: Gravimetric analyzes measured airborne particle concentrations, and filters were analyzed for metal content. In addition, concentrations of airborne particles <300 nm were investigated. Particles from recycled powder were characterized. Biomonitoring of urine and dermal contamination among AM operators, office personnel, and welders was performed.Results: Total and inhalable dust levels were almost all below occupational exposure limits, but inductively coupled plasma mass spectrometry showed that AM operators had a significant increase in cobalt exposure compared with welders. Airborne particle concentrations (<300 nm) showed transient peaks in the AM facility but were lower than those of the welding facility. Particle characterization of recycled powder showed fragmentation and condensates enriched in volatile metals. Biomonitoring showed a nonsignificant increase in the level of metals in urine in AM operators. Dermal cobalt and a trend for increasing urine metals during Workweek Year 1, but not in Year 2, indicated reduced exposure after preventive actions.Conclusion: Gravimetric analyses showed low total and inhalable dust exposure in AM operators. However, transient emission of smaller particles constitutes exposure risks. Preventive actions implemented by the company reduced the workers' metal exposure despite unchanged emissions of particles, indicating a need for careful design and regulation of the AM environments. It also emphasizes the need for relevant exposure markers and biomonitoring of health risks.
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40.
  • Ljunggren, Stefan, et al. (författare)
  • Changes in Human Liportein Composition in Patients with Acute Coronary Syndrome
  • 2011
  • Ingår i: Atherosclerosis Supplements. - : Elsevier. - 1567-5688 .- 1878-5050. ; 12:1, s. 14-14
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • The protein composition of lipoproteins may serve as biomarkers or reveal underlying mechanisms during different states of disease. Here we have analysed the protein composition of LDL and HDL from patients with acute coronary syndrome (ACS) and patients receiving statins after previous ACS. Plasma samples were obtained from males, namely 12 healthy donors, 9 patients with ACS and 7 stable patients receiving statin treatment after previous ACS. LDL and HDL were isolated by two-step density ultracentrifugation. LDL proteins were analysed with two-dimensional gel electrophoresis and mass spectrometry. Paraoxonase 1 (PON-1) in HDL was analyzed with  SDSPAGE/Western Blot.Concentrations of apo A-IV, a1-antitrypsin and transthyretin were significantly increased (P < 0.05) in LDL from patients with ACS compared to healthy controls. In patients receiving statins, a1-antitrypsin remained increased while serum amyloid A4 was decreased. By western blot analysis, a non-significant increase in PON-1 was found in HDL from patients with ACS. Interestingly, a truncated form of PON-1 was detected in all patients with ACS but not in any of the controls.In conclusion, we confirm previous findings that LDL-associated transthyretin is a possible biomarker of myocardial infarction. Moreover, the increased concentration of the inflammatory marker a1-antitrypsin in LDL from both ACS patients and stable patients after ACS indicate that the enrichment does not only reflect an acute phase response. The presence of a truncated form of the antioxidant protein PON-1 in HDL may explain previous findings showing increased amounts but lower activity of PON-1 in patients with ACS.
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41.
  • Ljunggren, Sofia, et al. (författare)
  • Decision-making under ambiguity after frontal lobe resection for epilepsy
  • 2023
  • Ingår i: Epilepsy and Behavior. - 1525-5050 .- 1525-5069. ; 142
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Decision-making is crucial to daily life and can impact our society as well as economic conditions. Although the frontal lobes have been identified as important for decision-making, this capacity has only been studied to a limited extent in frontal lobe epilepsy and not at all after frontal lobe resection (FLR) for epilepsy. This study aimed to explore decision-making under ambiguity after FLR for epilepsy. Methods: Fourteen patients having undergone FLR for epilepsy completed the Iowa Gambling Task (IGT) which is a widely used tool to measure decision-making under ambiguity. Iowa Gambling Task scores included in the analysis were: total net score, separate scores from five blocks across the test, and a change score (last block of IGT minus first block). A group of healthy controls (n = 30) was used as a comparison. Associations between IGT and standardized neuropsychological methods for assessment of executive functions, self-rating questionnaires of mental health, fatigue, and behavior linked to frontal lobe dysfunction were also investigated. Results: The patient group performed inferior to controls at the final block of the IGT (p =.001). A group difference in IGT change scores was found (p =.005), reflecting the absence of a positive change in performance over time for the FLR group compared to the control group. Correlations with tests of executive functions as well as self-rating scales were mainly statistically nonsignificant. Conclusions: This study shows that patients having undergone FLR for epilepsy have difficulties with decision-making under ambiguity. The performance illustrated a failure to learn throughout the task. Executive as well as emotional deficits may impact decision-making processes in this patient group and need to be considered in further studies. Prospective studies with larger cohorts are needed.
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42.
  • Ljunggren, Sofia, et al. (författare)
  • Experiences of emotional and psychosocial functioning after frontal lobe resection for epilepsy
  • 2021
  • Ingår i: Epilepsy & Behavior. - : Elsevier BV. - 1525-5050 .- 1525-5069. ; 121
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: Frontal lobe resection (FLR) is the second most common epilepsy surgery procedure in adults. Few studies address neuropsychological consequences after FLR. The aim of this study was to explore patients' and relatives' experiences of cognitive, emotional and social cognitive functioning after frontal lobe epilepsy surgery. Methods: Semi-structured interviews were held with 14 patients having gone through FLR as adults during the years 2000-2016 and 12 of their relatives. Interviews were audio-recorded, transcribed and analyzed with inductive qualitative content analysis. Results: Positive as well as negative consequences were described both by patients and relatives. Feelings of relief and an increased capacity to experience emotions of well-being were mainly experienced as related to seizure freedom. A newfound autonomy and a more grown-up identity as opposed to a selfimage based on epilepsy was also highlighted. However, results also showed that even for seizure free patients, FLR could give rise to negative experiences, the most prominent of which were mental fatigue, lowered mood and social withdrawal. Coping strategies included planning ahead to avoid mental exhaustion. Over all, respondents considered that the epilepsy surgery had been a risk well worth taking and that positive consequences outweighed the negative ones. Conclusions: This study shows a range of positive as well as negative outcomes after FLR for epilepsy. The findings indicate that lowered mood and mental fatigue could affect the life situation in a negative way, regardless of seizure outcome. This is important to consider in the preoperative counselling of patients and their families, as well as in the postsurgical follow-up. It is also crucial that the epilepsy surgery team has the possibility to offer rehabilitation and support to families regarding these aspects after surgery. (c) 2021 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
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43.
  • Ljunggren, Stefan (författare)
  • Fluid and nutrition support before total hip replacement surgery
  • 2013
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Surgical trauma results in a variety of physiological reactions in the body, including transient insulin resistance. The effect of surgery on postoperative wellbeing has been linked to this insulin resistance, which can be prevented through the ingestion of carbohydrate-rich liquid before surgery. The aim of this Thesis is to improve the clinical usefulness of the intravenous glucose tolerance test (IVGTT) by shortening the sampling time from 3 hours to 75 minutes and to use the IVGTT, and two other simple tests (QUICKI and HOMA-IR), to study whether most or all of the beneficial effects of the carbohydrate drink on postoperative insulin resistance can be explained by the water component of the drink. Study I: Twenty healthy volunteers underwent a 75-min IVGTT. Insulin resistance was then assessed using the hyperinsulinemic glucose clamp technique, regarded as the gold- standard method. The resultant measurements of plasma glucose and insulin concentrations during the IVGTT were combined, using a variety of algorithms, allowing the insulin resistance, as measured by the clamp, to be predicted in 2/3 and 4/5 of subjects. Study II: Sixty non-diabetic patients scheduled for hip replacement surgery were randomized into preoperative fasting (control), drink flavored water (placebo) or carbohydrate-rich liquid group. An IVGTT was performed the day before surgery, immediately afterwards, and the day after the surgery. No statistically significant differences were found with regard to glucose clearance, insulin resistance, postoperative complications or wellbeing between the three study groups. Study III: A double-blind clinical trial was performed in which twenty-three non-diabetic patients underwent both an IVGTT and a hyperinsulinemic glucose clamp test on the day before and two days after hip replacement surgery. Half of the patients received a carbohydrate-rich liquid before the surgery; the other half received a placebo. There was a similar development of insulin resistance in both groups, but those who received a carbohydrate-rich liquid showed an increase in β-cell activity. Study IV: Twenty-two patients from Study III were used to compare the insulin resistance results obtained from two dynamic tests (our short 7-sample IVGTT and the glucose clamp) and two static tests (QUICKI and HOMA-IR). The static tests showed slightly weaker linearity and larger residual errors compared to IVGTT in estimating insulin resistance before and after surgery. More importantly, they greatly underestimated the degree of surgery-induced insulin resistance, suggesting that they should not be used for that purpose. Conclusions: The simplified IVGTT results strongly correlated with those obtained used the hyperinsulinemic glucose clamp technique, which makes its use possible in the clinical setting. There was no statistical difference in surgery-induced insulin resistance between those who had received a carbohydrate-rich beverage or flavored water prior to hip replacement surgery. In addition, similar outcomes were seen in patients who had received a pretreatment carbohydrate-rich beverage, water or fasted preoperatively with regard to well-being and complications. HOMA and QUICKI should not be used to assess surgery-induced changes in insulin resistance.
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44.
  • Ljunggren, Stefan, et al. (författare)
  • Insulin sensitivity and beta-cell function after carbohydrate oral loading in hip replacement surgery : A double-blind, randomised controlled clinical trial
  • 2014
  • Ingår i: Clinical Nutrition. - : Elsevier. - 0261-5614 .- 1532-1983. ; 33:3, s. 392-398
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND & AIMS: Surgery initiates a series of physiological stress processes in the body, inducing transient insulin resistance. Preoperative carbohydrate treatment can reduce the latter phenomenon. We investigated the effects of carbohydrate loading on insulin sensitivity and beta-cell function after elective hip replacement.METHODS: Twenty-three nondiabetic patients (mean age of 68 years) who underwent elective hip replacement surgery participated in this double-blind controlled study. The patients were randomised to a nutrition group, which ingested a carbohydrate-rich fluid (50 kcal/100 ml) (Preop(®)), or a control group (tap water flavoured with lemon) 800 ml + 400 ml before the surgery. The insulin response (beta-cell function) and the insulin sensitivity were measured with an intravenous glucose tolerance test (IVGTT) and a hyperinsulinaemic euglycaemic glucose clamp, respectively, one day before and two days after the surgery.RESULTS: Insulin sensitivity decreased by 51% (median; 25-75th percentiles 35-61) after ingesting Preop(®) and by 39% (21-51) after ingesting in the control group (n.s.). The postoperative IVGTT in the nutrition group was followed by a significantly larger area under the curve (AUC) for plasma insulin (+54% versus the preoperative IVGTT) compared to the control group (+7%). This difference was already apparent during the first phase (0-10 min) of insulin secretion (+20 and -21%, respectively; P < 0.05).CONCLUSIONS: The patients randomised to the carbohydrate oral fluid or the water prior to the surgery demonstrated a significant but similar decrease in insulin sensitivity. The carbohydrates increased the beta-cell function as a compensatory response to the disposition index, resulting in a smaller reduction in surgery-induced insulin resistance compared to the tap water. The study was registered at http://www.clinicaltrials.gov (NCT01774084).
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45.
  • Ljunggren, Stefan, 1988- (författare)
  • Lipoproteomics : Environmental and Genetic Factors Affecting High-Density Lipoprotein (HDL)
  • 2016
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Lipoprotein particles act as lipid transporters in the blood stream, and measuring cholesterol content in specific subclasses of lipoprotein particles has long been, and still is, a frequently used tool to estimate the risk of cardiovascular disease (CVD). High-density lipoprotein (HDL) is a subclass of lipoproteins often regarded as providing protection against CVD via several functions including reverse cholesterol transport and anti-inflammatory capacities. However, the precise relationship between HDL cholesterol levels and health outcome is still unclear. Lately, new approaches to study HDL composition and function have therefore become more important.HDL function is to a large extent dependent on its proteome, containing more than 100 proteins. Investigating the proteome in individuals with altered gene expression for HDL-associated proteins or with known exposure to environmental contaminants may reveal new insights into how HDL metabolism is affected by various factors. This is of interest in order to better understand the role of HDL in CVD.Papers I and II focus on two different mutations in a structural HDL protein, apolipoprotein A-I (L202P and K131del), and one mutation in the scavenger receptor class B-1 (P297S), which is involved in selective lipid uptake of cholesterol mainly into hepatocytes and adrenal cells. The HDL proteome was analyzed using two-dimensional gel electrophoresis and mass spectrometry. The L202P mutation was identified in HDL of the heterozygote carriers together with a significant decrease of apolipoprotein E and increased zinc-alpha-2-glycoprotein. By contrast, the second apolipoprotein AI mutation (K131del) was associated with significantly elevated alpha-1-antitrypsin and transthyretin levels. Protein analyses of the scavenger receptor class B1 P297S heterozygotes showed a significant increase in HDL apoL-1 along with increased free apoE. The carriers showed no difference in antioxidative capability but a significant increase in apoA-I methionine oxidation.Papers III and IV focus on persistent organic pollutants that may influence HDL composition and function. These compounds accumulate in humans, and exposure has been linked to an increased risk of CVD. To provide a better understanding of the HDL system in relation to pollutants, a population living in a contaminated area was studied. Persistent organic pollutants in isolated HDL were quantified using high-resolution gas chromatography mass spectrometry and significantly increased levels were found in individuals with CVD as compared to healthy controls. Furthermore, there was a significant negative association between the pollutants and paraoxonase-1 anti-oxidant activity. Studying the proteome with nano-liquid chromatography tandem mass spectrometry led to the identification of 118 proteins in HDL, of which ten were significantly associated with the persistent organic pollutants.In summary, the present studies demonstrate protein pattern alterations in HDL associated with inherited genetic variants or pollutant exposure. The studies also provide a set of methods that are useful tools to further comprehend the complexity of lipoprotein metabolism and function. The results are important in order to improve our understanding of HDL in CVD and to explain an increased risk of CVD associated with exposure to organic pollutants.
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46.
  • Ljunggren, Stefan, et al. (författare)
  • Metal additive manufacturing and possible clinical markers for the monitoring of exposure-related health effects
  • 2021
  • Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 16:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Additive manufacturing (AM) includes a series of techniques used to create products, in several different materials, such as metal, polymer or ceramics, with digital models. The main advantage of AM is that it allows the creation of complex structures, but AM promises several additional advantages including the possibility to manufacture on demand or replacing smaller worn parts by directly building on an existing piece. Therefore, the interest for and establishment of AM is rapidly expanding, which is positive, however it is important to be aware that new techniques may also result in new challenges regarding health and safety issues. Metals in blood and possible clinical effects due to metal exposure were investigated in AM operators at one of the first serial producing AM facilities in the world during two consecutive years with implementation of preventive measures in-between. As comparison, welders and office workers as control group were investigated. Health investigations comprised of surveys, lung function tests, antioxidant activity and vascular inflammation as well as renal- and hepatic function analysis. AM operators had significantly reduced nickel levels in blood (10.8 vs 6.2 nmol/L) as well as improved lung function (80 vs 92% of predicted) from year 1 to year 2. This is in line with previously published results displaying reduced exposure. Blood cobalt and nickel levels correlated with previously reported urinary levels, while blood chromium did not. Multivariate modelling showed that blood cobalt, antioxidant/inflammatory marker serum amyloid A1/serum paraoxonase/arylesterase 1 activity and the hepatic markers aspartate transaminase, alanine transaminase, and alkaline phosphatase were higher in AM operators compared to controls. The study show that the selected clinical analyses could function as a complement to metal analyses in biological fluids when investigating exposure-related health effects in AM operators. However, validation in larger cohorts is necessary before more definite conclusions could be drawn.
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47.
  • Ljunggren, Stefan, 1988-, et al. (författare)
  • Modified lipoproteins in periodontitis : a link to cardiovascular disease?
  • 2019
  • Ingår i: Bioscience Reports. - : Portland Press. - 0144-8463 .- 1573-4935. ; 39:3
  • Tidskriftsartikel (refereegranskat)abstract
    • There is a strong association between periodontal disease and atherosclerotic cardiovascular disorders. A key event in the development of atherosclerosis is accumulation of modified lipoproteins within the arterial wall. We hypothesize that patients with periodontitis have an altered lipoprotein profile towards an atherogenic form. Therefore, this study aims at identifying modifications of plasma lipoproteins in periodontitis. Lipoproteins from ten female patients with periodontitis and gender- and age-matched healthy controls were isolated by density-gradient-ultracentrifugation. Proteins were separated by two-dimensional gel-electrophoresis and identified by map-matching or by nano-liquid chromatography followed by mass spectrometry. ApoA-I methionine oxidation, Oxyblot, total antioxidant capacity and a multiplex of 71 inflammation-related plasma proteins were assessed.Reduced levels of apoJ, phospholipid transfer protein, apoF, complement C3, paraoxonase 3 and increased levels of alpha-1-antichymotrypsin, apoA-II, apoC-III were found in HDL from the patients. In LDL/VLDL, the levels of apoL-1 and platelet-activating factor acetylhydrolase as well as apo-B fragments were increased. Methionine oxidation of apoA-I was increased in HDL and showed a relationship with periodontal parameters. Alpha-1 antitrypsin and alpha-2-HS glycoprotein were oxidised in LDL/VLDL and antioxidant capacity was increased in the patient group. 17 inflammation-related proteins were important for group separation with the highest discriminating proteins identified as IL-21, Fractalkine, IL-17F, IL-7, IL-1RA and IL-2.Patients with periodontitis have an altered plasma lipoprotein profile, defined by altered protein levels as well as posttranslational and other structural modifications towards an atherogenic form, which supports a role of modified plasma lipoproteins as central in the link between periodontal and cardiovascular disease (CVD).
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48.
  • Ljunggren, Stefan, 1988-, et al. (författare)
  • Monthly variation in masses, metals and endotoxin content as well as pro-inflammatory response of airborne particles collected by TEOM monitors
  • 2019
  • Ingår i: Air quality, atmosphere and health. - : Springer. - 1873-9318 .- 1873-9326. ; 12:12, s. 1441-1448
  • Tidskriftsartikel (refereegranskat)abstract
    • Particle exposure has been linked to an increased incidence of cardiovascular disease. Furthermore, particle exposure has been shown to have a chronic inhibitory effect on lung development in young people and may result in increased respiratory problems in adults or children with respiratory-related diseases. In today’s urban environments, particle levels are mainly monitored gravimetrically; however, other factors such as particle size, shape and surface reactivity have recently been noted as highly important in relation to possible health outcomes. Here, particles from TEOM monitor filters placed in three different cities were studied. The purpose of the study was to investigate whether there are variations in particle masses, cadmium and lead contents, as well as endotoxin levels between locations and time points over the year and if this can be correlated to the particles ability to induce a pro-inflammatory response in vitro. Results showed that it is possible to detect variations at different locations and at different time points over the year and that cadmium, lead and endotoxin levels did not coincide with the increased total particle masses while endotoxin levels coincided with pro-inflammatory responses in vitro. The present study shows that filter analysis is a useful complement to gravimetric or particle-counting measurements in studies of particle-related health effects and will give useful information regarding future air quality measurements.
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49.
  • Ljunggren, Stefan, et al. (författare)
  • Oral nutrition or water loading before hip replacement surgery; a randomized clinical trial
  • 2012
  • Ingår i: Trials. - : BioMed Central. - 1745-6215. ; 13:97
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundSurgery induces insulin resistance that might be alleviated by a nutritional drink given preoperatively. The authors hypothesized that some of the beneficial effects of the drink could be attributed to the volume component (approximately 1 L) rather than to the nutrients.MethodsSixty patients scheduled for elective total hip replacement under spinal anesthesia were recruited to a clinical trial, and randomly allocated to preoperative fasting, to oral ingestion of tap water, or to oral ingestion of a carbohydrate drink. An intravenous glucose tolerance test calculated glucose clearance and insulin sensitivity on the day before surgery, in the postoperative ward, and on the day after surgery. Other parameters were stress (cortisol in plasma and urine), muscle catabolism (urinary 3-methylhistidine), and wellbeing.ResultsFifty-seven patients completed the study. In the postoperative ward, the glucose clearance and the insulin response had decreased from the previous day by 23% and 36%, respectively. Insulin sensitivity did not decrease until the next morning (−48%) and was due to an increased insulin response (+51%). Cortisol excretion was highest on the day of surgery, while 3-methylhistidine increased 1 day later. Follow-up on the third postoperative day showed an average of 1.5 complications per patient. Wellbeing was better 2 weeks after than before the surgery. None of the measured parameters differed significantly between the study groups.ConclusionsPreoperative ingestion of tap water or a nutritional drink had no statistically significant effect on glucose clearance, insulin sensitivity, postoperative complications, or wellbeing in patients undergoing elective hip surgery.
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50.
  • Lönn, Johanna, et al. (författare)
  • Lipoprotein modifications by gingipains of Porphyromonas gingivalis
  • 2018
  • Ingår i: Journal of Periodontal Research. - : Wiley-Blackwell Publishing Inc.. - 0022-3484 .- 1600-0765. ; 53:3, s. 403-413
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND AND OBJECTIVE: Several studies have shown an association between periodontitis and cardiovascular disease (CVD). Atherosclerosis is the major cause of CVD, and a key event in the development of atherosclerosis is accumulation of lipoproteins within the arterial wall. Bacteria are the primary etiologic agents in periodontitis and Porphyromonas gingivalis is the major pathogen in the disease. Several studies support a role of modified low-density lipoprotein (LDL) in atherogenesis; however, the pathogenic stimuli that induce the changes and the mechanisms by which this occur are unknown. This study aims to identify alterations in plasma lipoproteins induced by the periodontopathic species of bacterium, P. gingivalis, in vitro.MATERIAL AND METHODS: Plasma lipoproteins were isolated from whole blood treated with wild-type and gingipain-mutant (lacking either the Rgp- or Kgp gingipains) P. gingivalis by density/gradient-ultracentrifugation and were studied using 2-dimensional gel electrophoresis followed by matrix-assisted laser desorption/ionization mass spectrometry. Porphyromonas gingivalis-induced lipid peroxidation and antioxidant levels were measured by thiobarbituric acid-reactive substances and antioxidant assay kits, respectively, and lumiaggregometry was used for measurement of reactive oxygen species (ROS) and aggregation.RESULTS: Porphyromonas gingivalis exerted substantial proteolytic effects on the lipoproteins. The Rgp gingipains were responsible for producing 2 apoE fragments, as well as 2 apoB-100 fragments, in LDL, and the Kgp gingipain produced an unidentified fragment in high-density lipoproteins. Porphyromonas gingivalis and its different gingipain variants induced ROS and consumed antioxidants. Both the Rgp and Kgp gingipains were involved in inducing lipid peroxidation.CONCLUSIONS: Porphyromonas gingivalis has the potential to change the expression of lipoproteins in blood, which may represent a crucial link between periodontitis and CVD.
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