| 1. |
- Justice, A. E., et al.
(författare)
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Genome-wide meta-analysis of 241,258 adults accounting for smoking behaviour identifies novel loci for obesity traits
- 2017
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Few genome-wide association studies (GWAS) account for environmental exposures, like smoking, potentially impacting the overall trait variance when investigating the genetic contribution to obesity-related traits. Here, we use GWAS data from 51,080 current smokers and 190,178 nonsmokers (87% European descent) to identify loci influencing BMI and central adiposity, measured as waist circumference and waist-to-hip ratio both adjusted for BMI. We identify 23 novel genetic loci, and 9 loci with convincing evidence of gene-smoking interaction (GxSMK) on obesity-related traits. We show consistent direction of effect for all identified loci and significance for 18 novel and for 5 interaction loci in an independent study sample. These loci highlight novel biological functions, including response to oxidative stress, addictive behaviour, and regulatory functions emphasizing the importance of accounting for environment in genetic analyses. Our results suggest that tobacco smoking may alter the genetic susceptibility to overall adiposity and body fat distribution.
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| 2. |
- Graff, M., et al.
(författare)
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Genome-wide physical activity interactions in adiposity. A meta-analysis of 200,452 adults
- 2017
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Ingår i: PLoS Genet. - : Public Library of Science (PLoS). - 1553-7404 .- 1553-7390. ; 13:4
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Tidskriftsartikel (refereegranskat)abstract
- Physical activity (PA) may modify the genetic effects that give rise to increased risk of obesity. To identify adiposity loci whose effects are modified by PA, we performed genome-wide interaction meta-analyses of BMI and BMI-adjusted waist circumference and waist-hip ratio from up to 200,452 adults of European (n = 180,423) or other ancestry (n = 20,029). We standardized PA by categorizing it into a dichotomous variable where, on average, 23% of participants were categorized as inactive and 77% as physically active. While we replicate the interaction with PA for the strongest known obesity-risk locus in the FTO gene, of which the effect is attenuated by similar to 30% in physically active individuals compared to inactive individuals, we do not identify additional loci that are sensitive to PA. In additional genome-wide meta-analyses adjusting for PA and interaction with PA, we identify 11 novel adiposity loci, suggesting that accounting for PA or other environmental factors that contribute to variation in adiposity may facilitate gene discovery.
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| 3. |
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| 4. |
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| 5. |
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| 6. |
- Locke, Adam E, et al.
(författare)
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Genetic studies of body mass index yield new insights for obesity biology.
- 2015
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 518:7538, s. 197-401
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Tidskriftsartikel (refereegranskat)abstract
- Obesity is heritable and predisposes to many diseases. To understand the genetic basis of obesity better, here we conduct a genome-wide association study and Metabochip meta-analysis of body mass index (BMI), a measure commonly used to define obesity and assess adiposity, in up to 339,224 individuals. This analysis identifies 97 BMI-associated loci (P < 5 × 10(-8)), 56 of which are novel. Five loci demonstrate clear evidence of several independent association signals, and many loci have significant effects on other metabolic phenotypes. The 97 loci account for ∼2.7% of BMI variation, and genome-wide estimates suggest that common variation accounts for >20% of BMI variation. Pathway analyses provide strong support for a role of the central nervous system in obesity susceptibility and implicate new genes and pathways, including those related to synaptic function, glutamate signalling, insulin secretion/action, energy metabolism, lipid biology and adipogenesis.
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| 7. |
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| 8. |
- Shungin, Dmitry, et al.
(författare)
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New genetic loci link adipose and insulin biology to body fat distribution.
- 2015
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 518:7538, s. 187-378
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Tidskriftsartikel (refereegranskat)abstract
- Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms.
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| 9. |
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| 10. |
- Ried, Janina S., et al.
(författare)
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A principal component meta-analysis on multiple anthropometric traits identifies novel loci for body shape
- 2016
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Large consortia have revealed hundreds of genetic loci associated with anthropometric traits, one trait at a time. We examined whether genetic variants affect body shape as a composite phenotype that is represented by a combination of anthropometric traits. We developed an approach that calculates averaged PCs (AvPCs) representing body shape derived from six anthropometric traits (body mass index, height, weight, waist and hip circumference, waist-to-hip ratio). The first four AvPCs explain >99% of the variability, are heritable, and associate with cardiometabolic outcomes. We performed genome-wide association analyses for each body shape composite phenotype across 65 studies and meta-analysed summary statistics. We identify six novel loci: LEMD2 and CD47 for AvPC1, RPS6KA5/C14orf159 and GANAB for AvPC3, and ARL15 and ANP32 for AvPC4. Our findings highlight the value of using multiple traits to define complex phenotypes for discovery, which are not captured by single-trait analyses, and may shed light onto new pathways.
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| 11. |
- Surendran, Praveen, et al.
(författare)
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Trans-ancestry meta-analyses identify rare and common variants associated with blood pressure and hypertension
- 2016
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 48:10, s. 1151-1161
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Tidskriftsartikel (refereegranskat)abstract
- High blood pressure is a major risk factor for cardiovascular disease and premature death. However, there is limited knowledge on specific causal genes and pathways. To better understand the genetics of blood pressure, we genotyped 242,296 rare, low-frequency and common genetic variants in up to 192,763 individuals and used -1/4155,063 samples for independent replication. We identified 30 new blood pressure- or hypertension-associated genetic regions in the general population, including 3 rare missense variants in RBM47, COL21A1 and RRAS with larger effects (>1.5 mm Hg/allele) than common variants. Multiple rare nonsense and missense variant associations were found in A2ML1, and a low-frequency nonsense variant in ENPEP was identified. Our data extend the spectrum of allelic variation underlying blood pressure traits and hypertension, provide new insights into the pathophysiology of hypertension and indicate new targets for clinical intervention.
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| 12. |
- Gaulton, Kyle J, et al.
(författare)
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Genetic fine mapping and genomic annotation defines causal mechanisms at type 2 diabetes susceptibility loci.
- 2015
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 47:12, s. 1415-1415
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Tidskriftsartikel (refereegranskat)abstract
- We performed fine mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in or near KCNQ1. 'Credible sets' of the variants most likely to drive each distinct signal mapped predominantly to noncoding sequence, implying that association with T2D is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine mapping implicated rs10830963 as driving T2D association. We confirmed that the T2D risk allele for this SNP increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease.
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| 13. |
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| 14. |
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| 15. |
- Heikkila, H. M., et al.
(författare)
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Combined low-saturated fat intake and high fitness may counterbalance diabetogenic effects of obesity : the DR's EXTRA Study
- 2013
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Ingår i: European Journal of Clinical Nutrition. - : Nature Publishing Group. - 0954-3007 .- 1476-5640. ; 67:9, s. 1000-1002
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Tidskriftsartikel (refereegranskat)abstract
- We report associations of saturated fat (SF) intake with impaired fasting glucose (IFG), impaired glucose tolerance (IGT), concurrent IFG+IGT and type 2 diabetes (T2DM) at different levels of cardiorespiratory fitness and body mass index (BMI). In a population-based sample (n = 1261, age 58-78 years), oral glucose tolerance, 4-day food intake and maximal oxygen uptake were measured. High intake of SF (>11.4 E%) was associated with elevated risk for IFG (4.36; 1.93-9.88), concurrent IFG+IGT (6.03; 1.25-29.20) and T2DM (4.77; 1.93-11.82) in the category of high BMI (>26.5) and high fitness, whereas there was no significantly elevated risk in individuals reporting low intake of SF. Concurrent high BMI and low fitness were associated with elevated risks. In general, SF intake and fitness did not differentiate the risk of abnormal glucose metabolism among subjects with low BMI. Limited intake of SF may protect from diabetogenic effects of adiposity, but only in individuals with high level of fitness.
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| 16. |
- Komulainen, P, et al.
(författare)
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Carotid intima-media thickness and cognitive function in elderly women: a population-based study
- 2007
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Ingår i: Neuroepidemiology. - : S. Karger AG. - 1423-0208 .- 0251-5350. ; 28:4, s. 207-213
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Tidskriftsartikel (refereegranskat)abstract
- <i>Objective:</i> Several vascular risk factors have been linked to cognitive decline. However, little is known about the association between the atherosclerotic process and cognitive impairment. We investigated whether carotid intima-media thickness (IMT) predicts the risk of cognitive impairment and whether the putative impairment is specific for some cognitive domains. <i>Methods:</i> A 12-year population-based follow-up study was performed for a total of 91 women, aged 60–70 years at baseline. Ultrasonographically assessed carotid artery IMT and the Mini-Mental State Examination test were performed at baseline and 12-year follow-up. A detailed cognitive evaluation for memory and cognitive speed was performed in 2003. The mean of left and right carotid bifurcation IMT was used in the analyses for association with the risk for poor cognitive speed and memory. <i>Results:</i> Increased IMT at baseline was an independent predictor for poor memory (β = –5.004, 95% confidence interval = –7.74 to –2.27; p = 0.001) and cognitive speed (β = 2.562, 95% confidence interval = 1.19–4.94; p = 0.035) at 12-year follow-up after adjustment for age, education, depression, plasma LDL cholesterol, systolic blood pressure, cardiovascular disease, hormone replacement therapy, smoking, alcohol consumption and physical activity. The risk for poor memory (p = 0.023 for linear trend) and cognitive speed (p = 0.070 for linear trend) increased with increasing IMT tertiles. <i>Conclusions:</i> Carotid IMT predicts an increased risk for cognitive impairment, particularly poor memory and cognitive speed, in elderly women.
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| 17. |
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| 18. |
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| 19. |
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| 20. |
- Komulainen, P, et al.
(författare)
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Metabolic syndrome and cognitive function: a population-based follow-up study in elderly women
- 2007
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Ingår i: Dementia and geriatric cognitive disorders. - : S. Karger AG. - 1420-8008 .- 1421-9824. ; 23:1, s. 29-34
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Tidskriftsartikel (refereegranskat)abstract
- <i>Objective:</i> To test the hypothesis that metabolic syndrome predicts cognitive impairment, and to examine the association of single metabolic risk factors with cognitive functioning. <i>Methods:</i> Weperformed a 12-year follow-up study in a population-based sample of 101 women aged 60–70 years at baseline. Metabolic syndrome wasdefined by the National Cholesterol Education Program criteria (≧3 out of 5 risk factors). Global cognitive function was measured by the Mini-Mental State Examination both at baseline and follow-up. A detailed neuropsychological evaluation for memory and cognitive speed was performed at follow-up. <i>Results:</i> The prevalence of metabolic syndrome increased from 13% at baseline to 49% at follow-up (p < 0.001). Women with metabolic syndrome at baseline had a 4.27 (95% confidence interval: 1.02–17.90; p = 0.047) times higher risk of poor memory at follow-up after adjustment for age, education and depression. The increasing number of metabolic risk factors was associated with worsening of memory at follow-up (p = 0.034 for linear trend). Women with low baseline levels of high-density lipoprotein (HDL) cholesterol were more likely to have poor memory at follow-up than those with higher HDL levels (p = 0.028). The risk of having poor memory increased by 46.5% (95% confidence interval: 15–66%; p = 0.008) with 1 SD decrease in HDL cholesterol level. <i>Conclusion:</i> In elderly women, metabolic syndrome may be an important contributor to worsening of memory, which is an essential part of mild cognitive impairment.
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| 21. |
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| 22. |
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| 23. |
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| 24. |
- Bart, Genevieve, et al.
(författare)
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Fluorescence Resonance Energy Transfer (FRET) and Proximity Ligation Assays Reveal Functionally Relevant Homo-and Heteromeric Complexes among Hyaluronan Synthases HAS1, HAS2, and HAS3
- 2015
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Ingår i: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 290:18, s. 11479-11490
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Tidskriftsartikel (refereegranskat)abstract
- In vertebrates, hyaluronan is produced in the plasma membrane from cytosolic UDP-sugar substrates by hyaluronan synthase 1-3 (HAS1-3) isoenzymes that transfer N-acetylglucosamine (GlcNAc) and glucuronic acid (GlcUA) in alternative positions in the growing polysaccharide chain during its simultaneous extrusion into the extracellular space. It has been shown that HAS2 immunoprecipitates contain functional HAS2 homomers and also heteromers with HAS3 (Karousou, E., Kamiryo, M., Skandalis, S. S., Ruusala, A., Asteriou, T., Passi, A., Yamashita, H., Hellman, U., Heldin, C. H., and Heldin, P. (2010) The activity of hyaluronan synthase 2 is regulated by dimerization and ubiquitination. J. Biol. Chem. 285, 23647-23654). Here we have systematically screened in live cells, potential interactions among the HAS isoenzymes using fluorescence resonance energy transfer (FRET) and flow cytometric quantification. We show that all HAS isoenzymes form homomeric and also heteromeric complexes with each other. The same complexes were detected both in Golgi apparatus and plasma membrane by using FRET microscopy and the acceptor photobleaching method. Proximity ligation assays with HAS antibodies confirmed the presence of HAS1-HAS2, HAS2-HAS2, and HAS2-HAS3 complexes between endogenously expressed HASs. C-terminal deletions revealed that the enzymes interact mainly via uncharacterized N-terminal 86-amino acid domain(s), but additional binding site(s) probably exist in their C-terminal parts. Of all the homomeric complexes HAS1 had the lowest and HAS3 the highest synthetic activity. Interestingly, HAS1 transfection reduced the synthesis of hyaluronan obtained by HAS2 and HAS3, suggesting functional cooperation between the isoenzymes. These data indicate a general tendency of HAS isoenzymes to form both homomeric and heteromeric complexes with potentially important functional consequences on hyaluronan synthesis.
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| 25. |
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| 26. |
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| 27. |
- Hassinen, J., et al.
(författare)
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Deterioration of polyethylene pipes exposed to chlorinated water
- 2004
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Ingår i: Polymer degradation and stability. - : Elsevier BV. - 0141-3910 .- 1873-2321. ; 84:2, s. 261-267
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Tidskriftsartikel (refereegranskat)abstract
- Pipes of high-density polyethylene were exposed to chlorinated water at elevated temperatures. The materials were stabilised with hindered phenols and phosphites. Oxidation induction times measured by DSC showed that the stabilising system was rapidly chemically consumed by the action of chlorinated water. Size exclusion chromatography and DSC showed extensive polymer degradation strictly confined to the immediate surface of the unprotected inner wall material and to the amorphous phase of the semicrystalline polymer. The rate of growth of the layer of highly degraded polymer was constant. It is obvious from the data that the species responsible for the loss of antioxidant are soluble in the polymer but not very reactive with the polymer itself. The species responsible for polymer degradation, on the other hand, are very reactive with the polymer and/or have a very low solubility in the polymer.
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| 28. |
- Karpanen, Terhi, et al.
(författare)
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Overexpression of vascular endothelial growth factor-B in mouse heart alters cardiac lipid metabolism and induces myocardial hypertrophy
- 2008
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Ingår i: Circulation Research. - : American Heart Association. - 0009-7330 .- 1524-4571. ; 103:9, s. 1018-1026
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Tidskriftsartikel (refereegranskat)abstract
- Vascular endothelial growth factor (VEGF)-B is poorly angiogenic but prominently expressed in metabolically highly active tissues, including the heart. We produced mice expressing a cardiac-specific VEGF-B transgene via the alpha-myosin heavy chain promoter. Surprisingly, the hearts of the VEGF-B transgenic mice showed concentric cardiac hypertrophy without significant changes in heart function. The cardiac hypertrophy was attributable to an increased size of the cardiomyocytes. Blood capillary size was increased, whereas the number of blood vessels per cell nucleus remained unchanged. Despite the cardiac hypertrophy, the transgenic mice had lower heart rate and blood pressure than their littermates, and they responded similarly to angiotensin II-induced hypertension, confirming that the hypertrophy does not compromise heart function. Interestingly, the isolated transgenic hearts had less cardiomyocyte damage after ischemia. Significantly increased ceramide and decreased triglyceride levels were found in the transgenic hearts. This was associated with structural changes and eventual lysis of mitochondria, resulting in accumulation of intracellular vacuoles in cardiomyocytes and increased death of the transgenic mice, apparently because of mitochondrial lipotoxicity in the heart. These results suggest that VEGF-B regulates lipid metabolism, an unexpected function for an angiogenic growth factor.
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| 29. |
- Kuisma, H, et al.
(författare)
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Parity associates with chromosomal damage in uterine leiomyomas
- 2021
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 12:1, s. 5448-
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Tidskriftsartikel (refereegranskat)abstract
- Mechanical forces in a constrained cellular environment were recently established as a facilitator of chromosomal damage. Whether this could contribute to tumorigenesis is not known. Uterine leiomyomas are common neoplasms that display relatively few chromosomal aberrations. We hypothesized that if mechanical forces contribute to chromosomal damage, signs of this could be seen in uterine leiomyomas from parous women. We examined the karyotypes of 1946 tumors, and found a striking overrepresentation of chromosomal damage associated with parity. We then subjected myometrial cells to physiological forces similar to those encountered during pregnancy, and found this to cause DNA breaks and a DNA repair response. While mechanical forces acting in constrained cellular environments may thus contribute to neoplastic degeneration, and genesis of uterine leiomyoma, further studies are needed to prove possible causality of the observed association. No evidence for progression to malignancy was found.
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| 30. |
- Miglietta, F, et al.
(författare)
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Spatial and Temporal Performance of the MiniFACE (Free Air CO2 Enrichment) System on Bog Ecosystems in Northern and Central Europe
- 2001
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Ingår i: Environmental Monitoring & Assessment. - 1573-2959. ; 66:2, s. 107-127
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Tidskriftsartikel (refereegranskat)abstract
- The Bog Ecosystem Research Initiative (BERI) projectwas initiated to investigate, at five climaticallydifferent sites across Europe, the effects of elevatedCO2 and N deposition on the net exchange ofCO2 and CH4 between bogs and the atmosphere,and to study the effects of elevated CO2 and Ndeposition on the plant biodiversity of bogcommunities. A major challenge to investigate theeffects of elevated CO2 on vegetation andecosystems is to apply elevated CO2concentrations to growing vegetation without changingthe physical conditions like climate and radiation.Most available CO2 enrichment methods disturb thenatural conditions to some degree, for instance closedchambers or open top chambers. Free Air CO2Enrichment (FACE) systems have proven to be suitableto expose plants to elevated CO2 concentrationswith minimal disturbance of their natural environment.The size and spatial scale of the vegetation studiedwithin the BERI project allowed the use of a modifiedversion of a small FACE system called MiniFACE. Thispaper describes the BERI MiniFACE design as well asits temporal and spatial performance at the five BERIfield locations. The temporal performance of theMiniFACE system largely met the quality criteriadefined by the FACE Protocol. One minute averageCO2 concentrations measured at the centre of thering stayed within 20% of the pre-set target for morethan 95% of the time. Increased wind speeds werefound to improve the MiniFACE system's temporalperformance. Spatial analyses showed no apparentCO2 gradients across a ring during a 4 day periodand the mean differences between each sampling pointand the centre of the ring did not exceed 10%.Observations made during a windy day, causing aCO2 concentration gradient, and observations madeduring a calm day indicated that short term gradientstend to average out over longer periods of time. On aday with unidirectional strong winds, CO2concentrations at the upwind side of the ring centrewere higher than those made at the centre and at thedownwind side of the ring centre, but the bell-shapeddistribution was found basically the same for thecentre and the four surrounding measurement points,implying that the short term (1 sec) variability ofCO2 concentrations across the MiniFACE ring isalmost the same at any point in the ring. Based on gasdispersion simulations and measured CO2concentration profiles, the possible interferencebetween CO2-enriched and control rings was foundto be negligible beyond a centre-to-centre ringdistance of 6 m.
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| 31. |
- Männikkö, Reija, et al.
(författare)
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The Nordic diet and cognition - The DR's EXTRA Study
- 2015
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Ingår i: British Journal of Nutrition. - 0007-1145 .- 1475-2662. ; 114:2, s. 231-239
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Tidskriftsartikel (refereegranskat)abstract
- The rapid increase in the prevalence of dementia associated with ageing populations has stimulated interest in identifying modifiable lifestyle factors that could prevent cognitive impairment. One such potential preventive lifestyle factor is the Nordic diet that has been shown to reduce the risk of CVD; however, its effect on cognition has not been studied. The aim of the present study was to estimate the cross-sectional and longitudinal associations of the baseline Nordic diet with cognitive function at baseline and after a 4-year follow-up in a population-based random sample (n 1140 women and men, age 57-78 years) as secondary analyses of the Finnish Dose-Responses to Exercise Training study. The Nordic diet score was created based on reported dietary components in 4-d food records. Cognition was assessed by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological battery and the Mini-mental State Examination (MMSE). The baseline Nordic diet score had been positively associated with Verbal Fluency (beta 0.08 (95% CI 0.00, 0.16), P=0.039) and Word List Learning (beta 0.06 (95% CI 0.01, 0.10), P=0.022) at 4 years but not with the Consortium to Establish a Registry for Alzheimer's Disease total score (CERAD-TS) or MMSE at 4 years, after adjustment for baseline cognitive scores, demographic factors and health-related factors. After excluding individuals with impaired cognition at baseline, the baseline Nordic diet score had also been positively associated with the CERAD-TS (beta 0.10 (95% CI 0.00, 0.20), P=0.042) and MMSE (beta 0.03 (95% CI 0.00, 0.06), P=0.039) at 4 years. These associations disappeared after further adjustment for energy intake. In conclusion, the Nordic diet might have a positive association with cognition in individuals with normal cognition.
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| 32. |
- Savonen, K, et al.
(författare)
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The current standard measure of cardiorespiratory fitness introduces confounding by body mass : the DR's EXTRA study
- 2012
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Ingår i: International Journal of Obesity. - London : Nature Publishing Group. - 0307-0565 .- 1476-5497. ; 36:8, s. 1135-1140
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE:Cardiorespiratory fitness is currently estimated by dividing maximal oxygen consumption (VO(2max)) by body weight (per-weight standard). However, the statistically correct way to neutralize the effect of weight on VO(2max) in a given population is adjustment for body weight by regression techniques (adjusted standard). Our objective is to quantify the bias introduced by the per-weight standard in a population distributed across different categories of body mass.DESIGN:This is a cross-sectional study.SUBJECTS AND METHODS:Baseline measures from participants of the Dose-Responses to Exercise Training Study (DR's EXTRA), 635 men (body mass index (BMI): 19-47 kg m(-2)) and 638 women (BMI: 16-49 kg m(-2)) aged 57-78 years who performed oral glucose tolerance tests and maximal exercise stress tests with direct measurement of VO(2max). We compare the increase in VO(2max) implied by the per-weight standard with the real increase of VO(2max) per kg body weight. A linear logistic regression model estimates odds for abnormal glucose metabolism (either impaired fasting glycemia or impaired glucose tolerance or Type 2 diabetes) of the least-fit versus most-fit quartile according to both per-weight standard and adjusted standard.RESULTS:The per-weight standard implies an increase of VO(2max) with 20.9 ml min(-1) in women and 26.4 ml min(-1) in men per additional kg body weight. The true increase per kg is only 7.0 ml min(-1) (95% confidence interval: 5.3-8.8) and 8.0 ml min(-1) (95% confidence interval: 5.3-10.7), respectively. Risk for abnormal glucose metabolism in the least-fit quartile of the population is overestimated by 52% if the per-weight standard is used.CONCLUSIONS:In comparisons across different categories of body mass, the per-weight standard systematically underestimates cardiorespiratory fitness in obese subjects. Use of the per-weight standard markedly inflates associations between poor fitness and co-morbidities of obesity.International Journal of Obesity advance online publication, 22 November 2011; doi:10.1038/ijo.2011.212.
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