| 1. |
- Ankarberg-Lindgren, Carina, 1963, et al.
(författare)
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Methodological considerations in determining sex steroids in children: comparison of conventional immunoassays with liquid chromatography-tandem mass spectrometry.
- 2024
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Ingår i: Clinical chemistry and laboratory medicine. - 1437-4331. ; 62:1, s. 85-96
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Tidskriftsartikel (refereegranskat)abstract
- In laboratory medicine, external quality assessment (EQA) schemes have become versatile tools for detecting analytical flaws. However, EQA schemes are lacking for pediatric sex steroid levels. We aimed to investigate the suitability of different estradiol and testosterone immunoassays in a pediatric setting in comparison with clinical liquid chromatography-tandem mass spectrometry (LC-MS/MS) assays.The study was conducted by staff and the advisory group on endocrinology at Equalis, the Swedish provider of EQA schemes for laboratory medicine. The test material consisted of five pooled serum samples from children who were either prepubertal or in puberty. Clinical laboratories enrolled in Equalis EQA schemes for estradiol and testosterone were invited to participate, as were clinical laboratories using LC-MS/MS-assays. Samples were analyzed by either routine immunoassays (n=18) or in-house LC-MS/MS assays (n=3).For estradiol, LC-MS/MS assays showed a high degree of conformity with interlaboratory coefficients of variation (CV) below 24.2%. Reported levels were between 4.9±1.2 and 33.9±1.6pmol/L (group mean±standard deviation). The direct immunoassays had lower precision; their CVs were up to 81.4%. Reported concentrations were between 25.3±18.1 and 45.7±19.4pmol/L, an overestimation compared to LC-MS/MS. Testosterone LC-MS/MS also showed a high degree of conformity, CVs were below 13.4%, and reported concentrations were from 0.06±0.00 to 1.00±0.11nmol/L. The direct immunoassays had a larger discrepancy between results; CVs were up to 95.8%. Concentrations were between 0.12±0.11 and 0.85±0.23nmol/L.For the safe diagnosis and determination of sex steroids in children, analysis with mass spectrometry-based methods is recommended.
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| 2. |
- Barreto Henriksson, Helena, et al.
(författare)
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Indications of that migration of stem cells is influenced by the extra cellular matrix architecture in the mammalian intervertebral disc region
- 2015
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Ingår i: Tissue & Cell. - : Elsevier BV. - 0040-8166 .- 1532-3072. ; 47:5, s. 439-455
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Tidskriftsartikel (refereegranskat)abstract
- Disc-degeneration is believed a major cause for lumbar pain. Previously, potential stem cell niches in the intervertebral disc (IVD) region, located adjacent to epiphyseal plate was reported. The aim of the study was to examine migration of mesenchymal stem cells (MSCs), extracellular matrix (ECM) architecture in a potential cellular migration route (CMR; area located between the niche and IVD) and in the IVD in non-degenerated lapine- and in human degenerated IVD tissues. Human MSCs (n = 3), human degenerated IVD tissues (n = 10) and lapine IVDs (n = 10) were collected. The samples were examined by immunohistochemistry for stem cell markers; CD90, OCT3/4, pre-chondrocytic marker; GDF5, catabolic markers; MMP9, MMP13, inflammatory marker; IL1R, cellular migration markers; SNAI1, SNAI2, adhesion markers; β1-INTEGRIN and DDR2. In addition, gene-expression analyses (Real time PCR) were performed on additional samples. Further, time lapse studies were performed with hMSCs cultured on aligned COLL-I-fibers-coated glass-slides in DMEM-LG, 10% human serum containing fibroblast growth factor (bFGF). Results: Presence of stem cells (CD90+, OCT3/4 + ), pre-chondocytic cells (GDF5 + )and cells positive for migration markers (SNAI1+, SNAI2 + ), catabolic markers (MMP9+, MMP13 + ), inflammatory marker (IL1R + ), adhesion markers (DDR2+, B1-INTEGRIN + ) were detected (gene- and protein level) in investigated CMR and IVD regions. In the time lapse studies, MSCs alignment and protrusions were observed orientated in the same direction as collagen fibres. Results displays influence of ECM collagen architecture and collagen fiber spatial direction on migration of stem cells. The results can be useful when developing tissue-engineering strategies for disc-degeneration.
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| 3. |
- Barreto Henriksson, Helena, et al.
(författare)
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Support of Concept that Migrating Progenitor Cells from Stem Cell Niches Contribute to Normal Regeneration of the Adult Mammal Intervertebral Disc: A Descriptive study in the New Zeeland white Rabbit.
- 2012
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Ingår i: Spine. - 0362-2436 .- 1528-1159. ; 37:9, s. 722-732
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT: Study Design. Descriptive experimental study performed in rabbits of two age groups.Objective. To study and investigate presence of prechondrocytic cells and cell migration routes in the IVD region, to gain knowledge about the normal IVD regeneration pattern.Summary of Background Data. Disc degeneration is believed to play a major role in patients with chronic lumbar pain. Regeneration processes and cell migration within the intervertebral disc (IVD) have been sparsely described. Therefore it is of interest to increase knowledge of these processes in order to understand pathological conditions of the IVD.Methods. 5-bromo-2-deoxyuridine (BrdU) in vivo labelling was performed in two groups of rabbits, 3 and 9 months old at the beginning of the experiment, in total 27 rabbits. BrdU is incorporated into DNA during mitosis and then it is gradually diluted with each cell division until it finally disappears. Incorporation of BrdU was then visualized by immunohistochemistry (IHC) at different time points providing cell division pattern and presence of slow-cycling cells in the IVD region. IVD tissue was investigated by IHC for: Growth- and differentiation-factor-5 (GDF5), SOX9 (chondrogenic lineage markers), SNAIL homolog1 (SNAI1), SNAIL homolog2 (SLUG)(migration markers) and β1-INTEGRIN (cellular adhesion marker). In addition, GDF5, SOX9 and BMPRIB expression were investigated on genetic level.Results. BrdU+ cells were observed in early time points in the IVD niche, adjacent to the epiphyseal plate, at later time points mainly in outer region of the annulus fibrosus (AF) for both age groups of rabbits, indicating a gradual migration of cells. The presence of SLUG, SNAI1, GDF5, SOX9 and β1-INTEGRIN were found in same regions.Conclusion. The results suggest a cellular migration route from the IVD stem cell niche toward the AF and the inner parts of the IVD. These findings may be of importance for understanding IVD regenerative mechanisms and for future development of biological treatment strategies.
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| 4. |
- Ley, Cecilia, et al.
(författare)
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Effects of high mobility group box protein-1, interleukin-1 beta, and interleukin-6 on cartilage matrix metabolism in three-dimensional equine chondrocyte cultures
- 2011
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Ingår i: Connective Tissue Research. - : Informa UK Limited. - 0300-8207 .- 1607-8438. ; 52, s. 290-300
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Tidskriftsartikel (refereegranskat)abstract
- The effects of high mobility group box protein (HMGB)-1, interleukin (IL)-1 beta, and IL-6 on equine articular chondrocytes were investigated, with emphasis on detecting differences between anatomical sites exposed to different loading in vivo, using three-dimensional (3D) cell cultures established with chondrocytes from dorsal radial facet (DRF, highly loaded) and palmar condyle (PC, less loaded) of the third carpal bone (C3). Expression of important genes involved in cartilage metabolism, presence of glycosaminoglycans and cartilage oligomeric matrix protein (COMP) in pellets, and concentrations of matrix metalloproteinase (MMP)-13 and aggrecan epitope CS 846 were evaluated. Compared to controls, IL-1 beta treatment increased gene expression of versican, matrix-degrading enzymes, and tissue inhibitor of metalloproteinase (TIMP)-1, and decreased aggrecan and collagen type I and type II expression. In addition, IL-1 beta-treated pellets showed decreased safranin O staining and increased COMP immunostaining and MMP-13 concentrations in culture supernatants. Effects of IL-6 and HMGB-1 on gene expression were variable, although upregulation of Sry-related high-mobility group box 9 (Sox9) was often present and statistically increased in HMGB-1-treated pellets. Response to cytokines rarely differed between DRF and PC pellets. Thus, site-associated cartilage deterioration in equine carpal osteoarthritis (OA) is not explained by topographically different responses to inflammatory mediators. Differences in gene expressions of structural matrix proteins in untreated DRF and PC pellets were noted in the youngest horses, which may indicate differences in the chondrocytes potential to produce matrix in vivo. Overall, a strong catabolic response was induced by IL-1 beta, whereas slight anabolic effects were induced by IL-6 and HMGB-1.
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| 5. |
- Ley, Cecilia, et al.
(författare)
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Effects of high mobility group box protein-1, interleukin-1β, and interleukin-6 on cartilage matrix metabolism in three-dimensional equine chondrocyte cultures.
- 2011
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Ingår i: Connective tissue research. - : Informa UK Limited. - 1607-8438 .- 0300-8207. ; 52:4, s. 290-300
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Tidskriftsartikel (refereegranskat)abstract
- The effects of high mobility group box protein (HMGB)-1, interleukin (IL)-1β, and IL-6 on equine articular chondrocytes were investigated, with emphasis on detecting differences between anatomical sites exposed to different loading in vivo, using three-dimensional (3D) cell cultures established with chondrocytes from dorsal radial facet (DRF, highly loaded) and palmar condyle (PC, less loaded) of the third carpal bone (C3). Expression of important genes involved in cartilage metabolism, presence of glycosaminoglycans and cartilage oligomeric matrix protein (COMP) in pellets, and concentrations of matrix metalloproteinase (MMP)-13 and aggrecan epitope CS 846 were evaluated. Compared to controls, IL-1β treatment increased gene expression of versican, matrix-degrading enzymes, and tissue inhibitor of metalloproteinase (TIMP)-1, and decreased aggrecan and collagen type I and type II expression. In addition, IL-1β-treated pellets showed decreased safranin O staining and increased COMP immunostaining and MMP-13 concentrations in culture supernatants. Effects of IL-6 and HMGB-1 on gene expression were variable, although upregulation of Sry-related high-mobility group box 9 (Sox9) was often present and statistically increased in HMGB-1-treated pellets. Response to cytokines rarely differed between DRF and PC pellets. Thus, site-associated cartilage deterioration in equine carpal osteoarthritis (OA) is not explained by topographically different responses to inflammatory mediators. Differences in gene expressions of structural matrix proteins in untreated DRF and PC pellets were noted in the youngest horses, which may indicate differences in the chondrocytes potential to produce matrix in vivo. Overall, a strong catabolic response was induced by IL-1β, whereas slight anabolic effects were induced by IL-6 and HMGB-1.
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| 6. |
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| 7. |
- Löfgren, Maria, et al.
(författare)
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Cell and matrix modulation in prenatal and postnatal equine growth cartilage, zones of Ranvier and articular cartilage
- 2014
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Ingår i: Journal of Anatomy. - : Wiley. - 0021-8782 .- 1469-7580. ; 225:5, s. 548-568
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Tidskriftsartikel (refereegranskat)abstract
- Formation of synovial joints includes phenotypic changes of the chondrocytes and the organisation of their extracellular matrix is regulated by different factors and signalling pathways. Increased knowledge of the normal processes involved in joint development may be used to identify similar regulatory mechanisms during pathological conditions in the joint. Samples of the distal radius were collected from prenatal and postnatal equine growth plates, zones of Ranvier and articular cartilage with the aim of identifying Notch signalling components and cells with stem cell-like characteristics and to follow changes in matrix protein localisation during joint development. The localisation of the Notch signalling components Notch1, Delta4, Hes1, Notch dysregulating protein epidermal growth factor-like domain 7 (EGFL7), the stem cell-indicating factor Stro-1 and the matrix molecules cartilage oligomeric matrix protein (COMP), fibromodulin, matrilin-1 and chondroadherin were studied using immunohistochemistry. Spatial changes in protein localisations during cartilage maturation were observed for Notch signalling components and matrix molecules, with increased pericellular localisation indicating new synthesis and involvement of these proteins in the formation of the joint. However, it was not possible to characterise the phenotype of the chondrocytes based on their surrounding matrix during normal chondrogenesis. The zone of Ranvier was identified in all horses and characterised as an area expressing Stro-1, EGFL7 and chondroadherin with an absence of COMP and Notch signalling. Stro-1 was also present in cells close to the perichondrium, in the articular cartilage and in the fetal resting zone, indicating stem cell-like characteristics of these cells. The presence of stem cells in the articular cartilage will be of importance for the repair of damaged cartilage. Perivascular chondrocytes and hypertrophic cells of the cartilage bone interface displayed positive staining for EGFL7, which is a novel finding and suggests a role of EGFL7 in the vascular infiltration of growth cartilage.
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| 8. |
- Löfgren, Maria, et al.
(författare)
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Conditioned serum in vitro treatment of chondrocyte pellets and osteoarthritic explants
- 2023
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Ingår i: Equine Veterinary Journal. - : Wiley. - 0425-1644 .- 2042-3306. ; 55:2, s. 325-335
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Tidskriftsartikel (refereegranskat)abstract
- Background: Autologous conditioned serum (ACS) is used to treat osteoarthritis in horses, although its effects are not fully investigated. Objectives: To investigate the effects of equine serum and conditioned serum on chondrocytes stimulated with interleukin (IL)-1 beta and cartilage explants with mild osteoarthritis. Study design: In vitro experimental study. Methods: The effect of three different serum preparations (unincubated control [PS], serum incubated 24 h [PS24h] and serum incubated 24 h in ACS containers [PCS]) pooled from lame horses were tested in two in vitro models. IL-1 beta and IL-1 receptor antagonist (IL-1Ra) concentrations were measured in all sera. In model 1, chondrocyte pellet cultures were stimulated with IL-1 beta prior to treatment with the serum preparations for 2 and 48 h. Microarray, polymerase chain reaction, and matrix metallopeptidase-13 analyses were performed. In model 2, cartilage explants from horses with structural osteoarthritis were treated with PS or PCS on days 0, 6 and 12, or left untreated, and evaluated at day 24 using the OARSI grading scale for histological evaluation of articular cartilage. Results: The IL-1Ra concentration in PS24h and PCS was significantly higher than in PS. In model 1, inflammation- and cartilage matrix degradation-related genes were upregulated after 48 h in all treatment groups versus untreated controls. Cartilage matrix molecules, aggrecan and collagens, were downregulated in PS24h- and PCS-treated pellets versus untreated controls. Growth factor signalling genes were upregulated-FGF7 in all treatment groups, BMP2 in PS24h-, and INHBA in PCS-treated-compared with untreated controls. In model 2, the OARSI score at day 24 was not significantly different between treatment groups. Main limitations: Results from in vitro models cannot be directly translated to in vivo situations. Conclusions: In vitro treatment with conditioned serum did not alleviate IL-1 beta-induced responses in chondrocyte pellets or lead to morphological improvement in osteoarthritic cartilage explants.
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| 9. |
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| 10. |
- Löfgren, Maria, et al.
(författare)
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Time-dependent changes in gene expression induced in vitro by interleukin-1 beta in equine articular cartilage
- 2018
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Ingår i: Research in Veterinary Science. - : Elsevier BV. - 0034-5288 .- 1532-2661. ; 118, s. 466-476
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Tidskriftsartikel (refereegranskat)abstract
- Osteoarthritis is an inflammatory and degenerative joint disease commonly affecting horses. To identify genes of relevance for cartilage pathology in osteoarthritis we studied the time-course effects of interleukin (IL)-1 beta on equine articular cartilage. Articular cartilage explants from the distal third metacarpal bone were collected postmortem from three horses without evidence of joint disease. The explants were stimulated with IL-1 beta for 27 days and global gene expression was measured by microarray. Gene expression was compared to that of unstimulated explants at days 3, 9, 15, 21 and 27. Release of inflammatory proteins was measured using Proximity Extension Assay. Stimulation with IL-1 beta led to time-dependent changes in gene expression related to inflammation, the extracellular matrix (ECM), and phenotypic alterations. Gene expression and protein release of cytokines, chemokines, and matrix-degrading enzymes increased in the stimulated explants. Collagen type II was down regulated from day 15, whereas other ECM molecules were downregulated earlier. In contrast molecules involved in ECM signaling (perlecan, chondroitin sulfate proteoglycan 4, and syndecan 4) were upregulated. At the late time points, genes related to a chondrogenic phenotype were downregulated, and genes related to a hypertrophic phenotype were upregulated, suggesting a transition towards hypertrophy later in the culturing period. The data suggest that this in vitro model mimics time course events of in vivo inflammation in OA and it may be valuable as an in vitro tool to test treatments and to study disease mechanisms.
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