| 31. |
- Jensen, Vivi Flou Hjorth, et al.
(författare)
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Importance of gestational hypoglycaemia for foetal malformations and skeletal development in rats
- 2020
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Ingår i: Reproductive Toxicology. - : Elsevier BV. - 0890-6238. ; 91, s. 14-26
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to investigate embryo-foetal effects of continuous maternal insulin-induced hypoglycaemia extending throughout gestation or until gestation day (GD)17 (typical last day of dosing during pre-clinical evaluation) providing comparator data for safety assessment of longer-acting insulin analogues in non-diabetic rats. Pregnant rats received human insulin (HI)-infusion during gestation until either GD20 or GD17 (HI-GD20; HI-GD17). On GD20, foetal abnormalities and skeletal ossification/mineralisation were evaluated. HI-infusion induced continuous hypoglycaemia. Foetal skeletal and eye malformations (e.g. bent ribs, microphthalmia) were common in both groups. Foetal size and skeletal ossification/mineralisation decreased, particularly with infusion throughout gestation. Concluding, insulin-induced hypoglycaemia during gestation in non-diabetic rats is damaging to embryo-foetal growth and skeletal development, particularly after GD17. Three days without HI-infusion after GD17 allows for some developmental catch-up. Eye development is sensitive to HI-infusion before GD17. These results should serve as a benchmark during pre-clinical safety assessment of longer-acting insulin analogues tested in rats.
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| 32. |
- Jensen, Vivi F.H., et al.
(författare)
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Inner histopathologic changes and disproportionate zone volumes in foetal growth plates following gestational hypoglycaemia in rats
- 2020
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Maternal hypoglycaemia throughout gestation until gestation day (GD)20 delays foetal growth and skeletal development. While partially prevented by return to normoglycaemia after completed organogenesis (GD17), underlying mechanisms are not fully understood. Here, we investigated the pathogenesis of these changes and significance of maternal hypoglycaemia extending beyond organogenesis in non-diabetic rats. Pregnant rats received insulin-infusion until GD20 or GD17, with sacrifice on GD20. Hypoglycaemia throughout gestation increased maternal corticosterone levels, which correlated with foetal levels. Growth plates displayed central histopathologic changes comprising disrupted cellular organisation, hypertrophic chondrocytes, and decreased cellular density; expression of pro-angiogenic factors, HIF-1α and VEGF-A increased in surrounding areas. Disproportionately decreased growth plate zone volumes and lower expression of the structural protein MATN-3 were seen, while bone ossification parameters were normal. Ending maternal/foetal hypoglycaemia on GD17 reduced incidence and severity of histopathologic changes and with normal growth plate volume. Compromised foetal skeletal development following maternal hypoglycaemia throughout gestation is hypothesised to result from corticosterone-induced hypoxia in growth plates, where hypoxia disrupts chondrocyte maturation and growth plate structure and volume, decreasing long bone growth. Maternal/foetal hypoglycaemia lasting only until GD17 attenuated these changes, suggesting a pivotal role of glucose in growth plate development.
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| 33. |
- Khan, Jalaluddin A., et al.
(författare)
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Osteoporosis knowledge and awareness among university students in Saudi Arabia
- 2019
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Ingår i: Archives of Osteoporosis. - : Springer Science and Business Media LLC. - 1862-3522 .- 1862-3514. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Awareness and knowledge about any disease is the first step to prevent and treat it, so this study evaluates osteoporosis awareness and knowledge in university students. Our results showed a high awareness and good knowledge of osteoporosis. Females were better informed than males. Knowledge increased with increasing education level. PURPOSE: Osteoporosis is a worldwide health problem, including Saudi Arabia where vitamin D deficiency is common. Prevention of osteoporosis must begin by increasing awareness of the disease from a young age. This study aimed to assess awareness and knowledge of osteoporosis among young adults (18-30 years) attending Saudi universities, exploring the relationship between education and gender and the sources of information in this age group. METHODS: A cross-sectional survey was conducted in 337 students (176 females; 161 males) randomly selected from four Saudi universities during January-December 2017. Education level ranged from preparatory year to undergraduate and postgraduate levels. A self-reported questionnaire was designed to assess awareness and knowledge of osteoporosis across several domains, including risk factors for the disease, prevalence, symptoms, prevention, and treatment. RESULTS: Overall, 92% of students had some awareness of osteoporosis through a variety of sources, predominantly via friends. Just over half of all students had a good or high knowledge level overall (53.4 ± 16.6%). Knowledge score correlated with education (r2 = 0.28) and gender (r2 = 0.27); p < 0.0001. Females were better informed than males (57.7 ± 15.4% vs 48.8 ± 16.8%; p < 0.0001). Knowledge increased with increasing education level (preparatory year (47.8 ± 15.3%), undergraduate (53.5 ± 16.5%), and postgraduate (61.8 ± 15.8%); all p < 0.0001). CONCLUSION: Knowledge of osteoporosis was good among university students in Saudi Arabia, higher in females and with increasing years of education. Overall, students were more knowledgeable about risk factors compared to other aspects such as symptoms, prevention, or treatment of osteoporosis.
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| 34. |
- Koller, Daniel L., et al.
(författare)
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Meta-analysis of genome-wide studies identifies WNT16 and ESR1 SNPs associated with bone mineral density in premenopausal women
- 2013
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Ingår i: Journal of Bone and Mineral Research. - : Wiley. - 1523-4681 .- 0884-0431. ; 28:3, s. 547-558
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Tidskriftsartikel (refereegranskat)abstract
- Previous genome-wide association studies (GWAS) have identified common variants in genes associated with variation in bone mineral density (BMD), although most have been carried out in combined samples of older women and men. Meta-analyses of these results have identified numerous single-nucleotide polymorphisms (SNPs) of modest effect at genome-wide significance levels in genes involved in both bone formation and resorption, as well as other pathways. We performed a meta-analysis restricted to premenopausal white women from four cohorts (n=4061 women, aged 20 to 45 years) to identify genes influencing peak bone mass at the lumbar spine and femoral neck. After imputation, age- and weight-adjusted bone-mineral density (BMD) values were tested for association with each SNP. Association of an SNP in the WNT16 gene (rs3801387; p=1.7x109) and multiple SNPs in the ESR1/C6orf97 region (rs4870044; p=1.3x108) achieved genome-wide significance levels for lumbar spine BMD. These SNPs, along with others demonstrating suggestive evidence of association, were then tested for association in seven replication cohorts that included premenopausal women of European, Hispanic-American, and African-American descent (combined n=5597 for femoral neck; n=4744 for lumbar spine). When the data from the discovery and replication cohorts were analyzed jointly, the evidence was more significant (WNT16 joint p=1.3x1011; ESR1/C6orf97 joint p=1.4x1010). Multiple independent association signals were observed with spine BMD at the ESR1 region after conditioning on the primary signal. Analyses of femoral neck BMD also supported association with SNPs in WNT16 and ESR1/C6orf97 (p<1x105). Our results confirm that several of the genes contributing to BMD variation across a broad age range in both sexes have effects of similar magnitude on BMD of the spine in premenopausal women. These data support the hypothesis that variants in these genes of known skeletal function also affect BMD during the premenopausal period. (c) 2013 American Society for Bone and Mineral Research.
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| 35. |
- Kumar, Jitender, et al.
(författare)
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LRP4 association to bone properties and fracture and interaction with genes in the Wnt- and BMP signaling pathways.
- 2011
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Ingår i: Bone. - : Elsevier BV. - 1873-2763 .- 8756-3282. ; 49, s. 343-348
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Tidskriftsartikel (refereegranskat)abstract
- Osteoporosis is a common complex disorder in postmenopausal women leading to changes in the micro-architecture of bone and increased risk of fracture. Members of the low-density lipoprotein receptor-related protein (LRP) gene family regulates the development and physiology of bone through the Wnt/β-catenin (Wnt) pathway that in turn cross-talks with the bone morphogenetic protein (BMP) pathway. In two cohorts of Swedish women: OPRA (n=1002; age 75years) and PEAK-25 (n=1005; age 25years), eleven single nucleotide polymorphisms (SNPs) from Wnt pathway genes (LRP4; LRP5; G protein-coupled receptor 177, GPR177) were analyzed for association with Bone Mineral Density (BMD), rate of bone loss, hip geometry, quantitative ultrasound and fracture. Additionally, interaction of LRP4 with LRP5, GPR177 and BMP2 were analyzed. LRP4 (rs6485702) was associated with higher total body (TB) and lumbar spine (LS) BMD in the PEAK-25 cohort (p=0.006 and 0.005 respectively), and interaction was observed with LRP5 (p=0.007) and BMP2 (p=0.004) for TB BMD. LRP4 also showed significant interaction with LRP5 for femoral neck (FN) and LS BMD in this cohort. In the OPRA cohort, LRP4 polymorphisms were associated with significantly lower fracture incidence overall (p=0.008-0.001) and fewer hip fractures (rs3816614, p=0.006). Significant interaction in the OPRA cohort was observed for LRP4 with BMP2 and GPR177 for FN BMD as well as for rate of bone loss at TB and FN (p=0.007-0.0001). In conclusion, LRP4 and interaction between LRP4 and genes in the Wnt and BMP signaling pathways modulate bone phenotypes including peak bone mass and fracture, the clinical endpoint of osteoporosis.
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| 36. |
- Lagerholm, Sofia, et al.
(författare)
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Genetic loci for bone architecture determined by three-dimensional CT in crosses with the diabetic GK rat.
- 2010
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Ingår i: Bone. - : Elsevier BV. - 1873-2763 .- 8756-3282. ; 47, s. 1039-1047
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Tidskriftsartikel (refereegranskat)abstract
- The F344 rat carries alleles contributing to bone fragility while the GK rat spontaneously develops type-2 diabetes. These characteristics make F344xGK crosses well suited for the identification of genes related to bone size and allow for future investigation on the association with type-2 diabetes. The aim of this study was to identify quantitative trait loci (QTLs) for bone size phenotypes measured by a new application of three-dimensional computed tomography (3DCT) and to investigate the effects of sex- and reciprocal cross. Tibia from male and female GK and F344 rats, representing the parental, F1 and F2 generations, were examined with 3DCT and analyzed for: total and cortical volumetric BMD, straight and curved length, peri- and endosteal area at mid-shaft. F2 progeny (108 male and 98 female) were genotyped with 192 genome-wide microsatellite markers (average distance 10cM). Sex- and reciprocal cross-separated QTL analyses were performed for the identification of QTLs linked to 3DCT phenotypes and true interactions were confirmed by likelihood ratio analysis in all F2 animals. Several genome-wide significant QTLs were found in the sex- and reciprocal cross-separated progeny on chromosomes (chr) 1, 3, 4, 9, 10, 14, and 17. Overlapping QTLs for both males and females in the (GKxF344)F2 progeny were located on chr 1 (39-67cM). This region confirms previously reported pQCT QTLs and overlaps loci for fasting glucose. Sex separated linkage analysis confirmed a male specific QTL on chr 9 (67-82cM) for endosteal area at the fibula site. Analyses separating the F2 population both by sex and reciprocal cross identified cross specific QTLs on chr 14 (males) and chr 3 and 4 (females). Two loci, chr 4 and 6, are unique to 3DCT and separate from pQCT generated loci. The 3DCT method was highly reproducible and provided high precision measurements of bone size in the rat enabling identification of new sex- and cross-specific loci. The QTLs on chr 1 indicate potential genetic association between bone-related phenotypes and traits affecting type-2 diabetes. The results illustrate the complexity of the genetic architecture of bone size phenotypes and demonstrate the importance of complementary methods for bone analysis.
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| 37. |
- Lagerholm, Sofia, et al.
(författare)
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Identification of Candidate Gene Regions in the Rat by Co-Localization of QTLs for Bone Density, Size, Structure and Strength.
- 2011
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:7
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Tidskriftsartikel (refereegranskat)abstract
- Susceptibility to osteoporotic fracture is influenced by genetic factors that can be dissected by whole-genome linkage analysis in experimental animal crosses. The aim of this study was to characterize quantitative trait loci (QTLs) for biomechanical and two-dimensional dual-energy X-ray absorptiometry (DXA) phenotypes in reciprocal F2 crosses between diabetic GK and normo-glycemic F344 rat strains and to identify possible co-localization with previously reported QTLs for bone size and structure. The biomechanical measurements of rat tibia included ultimate force, stiffness and work to failure while DXA was used to characterize tibial area, bone mineral content (BMC) and areal bone mineral density (aBMD). F2 progeny (108 males, 98 females) were genotyped with 192 genome-wide markers followed by sex- and reciprocal cross-separated whole-genome QTL analyses. Significant QTLs were identified on chromosome 8 (tibial area; logarithm of odds (LOD) = 4.7 and BMC; LOD = 4.1) in males and on chromosome 1 (stiffness; LOD = 5.5) in females. No QTLs showed significant sex-specific interactions. In contrast, significant cross-specific interactions were identified on chromosome 2 (aBMD; LOD = 4.7) and chromosome 6 (BMC; LOD = 4.8) for males carrying F344mtDNA, and on chromosome 15 (ultimate force; LOD = 3.9) for males carrying GKmtDNA, confirming the effect of reciprocal cross on osteoporosis-related phenotypes. By combining identified QTLs for biomechanical-, size- and qualitative phenotypes (pQCT and 3D CT) from the same population, overlapping regions were detected on chromosomes 1, 3, 4, 6, 8 and 10. These are strong candidate regions in the search for genetic risk factors for osteoporosis.
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| 38. |
- Malmgren, Linnea, et al.
(författare)
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Bone health as a co-morbidity of chronic kidney disease
- 2022
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Ingår i: Best Practice and Research: Clinical Rheumatology. - : Elsevier BV. - 1521-6942. ; 36:3
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Forskningsöversikt (refereegranskat)abstract
- Chronic kidney disease and osteoporosis commonly co-exist in aged patients. Chronic kidney disease affects bone health because of its effect on mineral metabolism in the syndrome, Chronic Kidney Disease Mineral and Bone Disorder, resulting in an increased risk of fractures. Hip fracture risk may be as much as four-fold higher in the worst affected. Tools to estimate fracture risk such as FRAX® and measuring bone density can be used in patients with chronic kidney disease; however, bone density may underestimate fracture risk in this population as it does not give information on bone quality. While osteoporosis treatment in patients with chronic kidney disease stage 1–3 does not differ from the general population, in the absence of Chronic Kidney Disease Mineral and Bone Disorder, patients with disease stage 4–5 require special consideration. It is, however, of the utmost importance that these patients receive pharmacological treatment because of their high risk of fractures.
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| 39. |
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| 40. |
- Malmgren, Linnea, et al.
(författare)
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Impaired selective renal filtration captured by eGFRcysC/eGFRcrea ratio is associated with mortality in a population based cohort of older women
- 2022
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 12:1
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Tidskriftsartikel (refereegranskat)abstract
- Deranged renal filtration of mid-sized (5-30 kDa) compared to smaller molecules (< 0.9 kDa) results in increased plasma levels of cystatin C (cysC) compared to creatinine resulting in a low eGFRcysC/eGFRcrea ratio. A ratio below 0.6 or 0.7, is termed shrunken pore syndrome (SPS), which in patient based studies is associated with mortality. Reference values for eGFRcysC/eGFRcrea ratio, the prevalence of SPS and the consequence of low eGFRcysC/eGFRcrea ratio in the general, elderly population are unknown. 75-yr old women (n = 849) from the population-based OPRA cohort, followed for 10-years had eGFR calculated with CKD-EPI study equation, and eGFRcysC/eGFRcrea ratio calculated. Mortality risk (HR [95% CI]) was estimated. Women with sarcopenia or on glucocorticoids were excluded. Almost 1 in 10 women (9%) had eGFRcysC/eGFRcrea ratio < 0.6 at age 75 and this did not increase appreciably with age. Women with ratio < 0.6 had higher 10-yr mortality risk compared with ratios > 0.9 (HRadj 1.6 [95% CI 1.1-2.5]). In elderly women eGFRcysC/eGFRcrea ratio < 0.6 is common and associated with increased mortality. Our results confirm patient-based findings, suggesting that identifying individuals with SPS may be clinically relevant to assessing mortality risk in the elderly.
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