| 1. |
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| 2. |
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| 3. |
- Brattsand, Maria, 1966-, et al.
(författare)
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SPINK9 : a selective, skin-specific Kazal-type serine protease inhibitor.
- 2009
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Ingår i: Journal of Investigative Dermatology. - : Nature Publishing Group. - 0022-202X .- 1523-1747. ; 129:7, s. 1656-1665
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Tidskriftsartikel (refereegranskat)abstract
- A previously unreported Kazal-type serine protease inhibitor, serine protease inhibitor Kazal type 9 (SPINK9), was identified in human skin. SPINK9 expression was strong in palmar epidermis, but not detectable or very low in non palmoplantar skin. Analysis of a human cDNA panel showed intermediate expression in thymus, pancreas, liver, and brain, and low or undetectable expression in other tissues. Using kallikrein-related peptidases (KLKs) 5, 7, 8, and 14, thrombin, trypsin, and chymotrypsin, inhibition with recombinant SPINK9 was seen only for KLK5 using low molecular weight substrates, with an apparent K(i) of 65 nM. Also KLK5 degradation of fibrinogen was totally inhibited by SPINK9. Slight inhibition of KLK8 using fibrinogen substrate could be observed using high concentrations of SPINK9. Analyses by surface plasmon resonance showed heterogeneous binding to SPINK9 of KLK5 and KLK8, but no binding of KLK7 or KLK14. KLK5 has been suggested to play a central role in skin desquamation as an initiating activating enzyme in proteolytic cascades formed by KLKs. An apparently KLK5-specific inhibitor, such as SPINK9, may play a significant regulatory role in such cascades. We suggest a possible role for SPINK9 in the site-specific epidermal differentiation of palms and soles.
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| 4. |
- Einarsdottir, Ingibjörg, 1951, et al.
(författare)
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Plasma growth hormone-binding protein levels in Atlantic salmon Salmo salar during smoltification and seawater transfer
- 2014
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Ingår i: Journal of Fish Biology. - : Wiley. - 0022-1112. ; 85:4, s. 1279-1296
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Tidskriftsartikel (refereegranskat)abstract
- Specific growth hormone (GH)-binding protein (Ghbp) was purified from Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss plasma with immunoprecipitation and characterized in cross-linking studies using autoradiography and western blots. The size of the Ghbp was estimated to be c. 53 kDa. A radioimmunoassay was established to measure Ghbp in salmonids, using antibodies specific against the extracellular segment of the S. salar growth hormone receptor 1 (grh1; GenBank AY462105). Plasma Ghbp levels were measured in S. salar smolts in fresh water and after transfer to seawater (SW; experiments 1 and 2), and in post-smolts kept at different salinities (0, 12, 22 and 34) for 3 months (experiment 3). A transient increase in plasma Ghbp, which lasted for 1 month or less, was noted in smolts after transfer to SW. Concomitantly, plasma GH and gill Na+-K+-ATPase activity increased during smoltification (in experiment 2). No difference in plasma Ghbp was evident between post-smolts kept at different salinities, although the fish kept at salinity 34 had higher plasma GH than the group kept at salinity 22 and higher hepatic ghr1 expression than post-smolts kept at salinity 12. This suggests that plasma Ghbp regulation may respond to salinity changes in the short term. The lack of correlation between Ghbp, plasma GH and hepatic ghr1 expression in the long-term post-smolt experiment indicates that Ghbp levels may be regulated independently of other components of the endocrine GH system in salmonids.
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| 5. |
- Heijl, Anders, et al.
(författare)
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Nordic research in ophthalmology.
- 2005
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Ingår i: Acta ophthalmologica Scandinavica. - : Wiley. - 1395-3907 .- 1600-0420. ; 83:3, s. 278-88
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Nordic ophthalmologists and vision scientists are active in many fields of eye research. This is most evident at the biannual Nordic Congress of Ophthalmology, most recently held in Malmö in June 2004. The authors here review some of the research in vision and ophthalmology presented at this meeting or published recently by Nordic scientists. This paper does not represent a comprehensive review of all Nordic research in the field, but attempts to give an overview of some of the activities underway in eye research in this part of the world.
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| 6. |
- Henriksson, Maria, et al.
(författare)
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A nonphosphorylated 14-3-3 binding motif on exoenzyme S that is functional in vivo
- 2002
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Ingår i: European Journal of Biochemistry. - : Wiley. - 0014-2956 .- 1432-1033. ; 269:20, s. 4921-4929
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Tidskriftsartikel (refereegranskat)abstract
- 14-3-3 proteins play an important role in a multitude of signalling pathways. The interactions between 14-3-3 and other signalling proteins, such as Raf and KSR (kinase suppressor of Ras), occur in a phospho-specific manner. Recently, a phosphorylation-independent interaction has been reported to occur between 14-3-3 and several proteins, for example 5-phosphatase, p75NTR-associated cell death executor (NADE) and the bacterial toxin Exoenzyme S (ExoS), an ADP-ribosyltransferase from Pseudomonas aeruginosa. In this study we have identified the amino acid residues on ExoS, which are responsible for its specific interaction with 14-3-3. Furthermore, we show that a peptide derived from ExoS, containing the 14-3-3 interaction site, effectively competes out the interaction between ExoS and 14-3-3. In addition, competition with this peptide blocks ExoS modification of Ras in our Ras modification assay. We show that the ExoS protein interacts with all isoforms of the 14-3-3 family tested. Moreover, in vivo an ExoS protein lacking the 14-3-3 binding site has a reduced capacity to ADP ribosylate cytoplasmic proteins, e.g. Ras, and shows a reduced capacity to change the morphology of infected cells.
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| 7. |
- Hsu, Y. H., et al.
(författare)
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Meta-Analysis of Genomewide Association Studies Reveals Genetic Variants for Hip Bone Geometry
- 2019
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Ingår i: Journal of Bone and Mineral Research. - : Wiley. - 0884-0431 .- 1523-4681. ; 34:7, s. 1284-1296
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Tidskriftsartikel (refereegranskat)abstract
- Hip geometry is an important predictor of fracture. We performed a meta-analysis of GWAS studies in adults to identify genetic variants that are associated with proximal femur geometry phenotypes. We analyzed four phenotypes: (i) femoral neck length; (ii) neck-shaft angle; (iii) femoral neck width, and (iv) femoral neck section modulus, estimated from DXA scans using algorithms of hip structure analysis. In the Discovery stage, 10 cohort studies were included in the fixed-effect meta-analysis, with up to 18,719 men and women ages 16 to 93 years. Association analyses were performed with similar to 2.5 million polymorphisms under an additive model adjusted for age, body mass index, and height. Replication analyses of meta-GWAS significant loci (at adjusted genomewide significance [GWS], threshold p <= 2.6 x 10(-8)) were performed in seven additional cohorts in silico. We looked up SNPs associated in our analysis, for association with height, bone mineral density (BMD), and fracture. In meta-analysis (combined Discovery and Replication stages), GWS associations were found at 5p15 (IRX1 and ADAMTS16); 5q35 near FGFR4; at 12p11 (in CCDC91); 11q13 (near LRP5 and PPP6R3 (rs7102273)). Several hip geometry signals overlapped with BMD, including LRP5 (chr. 11). Chr. 11 SNP rs7102273 was associated with any-type fracture (p = 7.5 x 10(-5)). We used bone transcriptome data and discovered several significant eQTLs, including rs7102273 and PPP6R3 expression (p = 0.0007), and rs6556301 (intergenic, chr.5 near FGFR4) and PDLIM7 expression (p = 0.005). In conclusion, we found associations between several genes and hip geometry measures that explained 12% to 22% of heritability at different sites. The results provide a defined set of genes related to biological pathways relevant to BMD and etiology of bone fragility. (c) 2019 American Society for Bone and Mineral Research.
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| 8. |
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| 9. |
- Israelsson, Pernilla, et al.
(författare)
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Immunoreactivity of LMO7 and other molecular markers as potential prognostic factors in oropharyngeal squamous cell carcinoma
- 2024
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Ingår i: BMC Oral Health. - : BioMed Central (BMC). - 1472-6831. ; 24:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Despite the better prognosis associated with human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC), some patients experience relapse and succumb to the disease; thus, there is a need for biomarkers identifying these patients for intensified treatment. Leucine-rich repeats and immunoglobulin-like domain (LRIG) protein 1 is a negative regulator of receptor tyrosine kinase signaling and a positive prognostic factor in OPSCC. Studies indicate that LRIG1 interacts with the LIM domain 7 protein (LMO7), a stabilizer of adherence junctions. Its role in OPSCC has not been studied before.Methods: A total of 145 patients diagnosed with OPSCC were enrolled. Immunohistochemical LMO7 expression and staining intensity were evaluated in the tumors and correlated with known clinical and pathological prognostic factors, such as HPV status and LRIG1, CD44, Ki67, and p53 expression.Results: Our results show that high LMO7 expression is associated with significantly longer overall survival (OS) (p = 0.044). LMO7 was a positive prognostic factor for OS in univariate analysis (HR 0.515, 95% CI: 0.267–0.994, p = 0.048) but not in multivariate analysis. The LMO7 expression correlated with LRIG1 expression (p = 0.048), consistent with previous findings. Interestingly, strong LRIG1 staining intensity was an independent negative prognostic factor in the HPV-driven group of tumors (HR 2.847, 95% Cl: 1.036–7.825, p = 0.043).Conclusions: We show for the first time that high LMO7 expression is a positive prognostic factor in OPSCC, and we propose that LMO7 should be further explored as a biomarker. In contrast to previous reports, LRIG1 expression was shown to be an independent negative prognostic factor in HPV-driven OPSCC.
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| 10. |
- Karasik, D., et al.
(författare)
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Disentangling the genetics of lean mass
- 2019
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Ingår i: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 109:2, s. 276-287
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Tidskriftsartikel (refereegranskat)abstract
- Background: Lean body mass (LM) plays an important role in mobility and metabolic function. We previously identified five loci associated with LM adjusted for fat mass in kilograms. Such an adjustment may reduce the power to identify genetic signals having an association with both lean mass and fat mass. Objectives: To determine the impact of different fat mass adjustments on genetic architecture of LM and identify additional LM loci. Methods: We performed genome-wide association analyses for whole-body LM (20 cohorts of European ancestry with n = 38,292) measured using dual-energy X-ray absorptiometry) or bioelectrical impedance analysis, adjusted for sex, age, age(2), and height with or without fat mass adjustments (Model 1 no fat adjustment; Model 2 adjustment for fat mass as a percentage of body mass; Model 3 adjustment for fat mass in kilograms). Results: Seven single-nucleotide polymorphisms (SNPs) in separate loci, including one novel LM locus (TNRC6B), were successfully replicated in an additional 47,227 individuals from 29 cohorts. Based on the strengths of the associations in Model 1 vs Model 3, we divided the LM loci into those with an effect on both lean mass and fat mass in the same direction and refer to those as "sumo wrestler" loci (FTO and MC4R). In contrast, loci with an impact specifically on LMwere termed "body builder" loci (VCAN and ADAMTSL3). Using existing available genome-wide association study databases, LM increasing alleles of SNPs in sumo wrestler loci were associated with an adverse metabolic profile, whereas LM increasing alleles of SNPs in "body builder" loci were associated with metabolic protection. Conclusions: In conclusion, we identified one novel LM locus (TNRC6B). Our results suggest that a genetically determined increase in lean mass might exert either harmful or protective effects on metabolic traits, depending on its relation to fat mass.
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| 11. |
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| 12. |
- Loizou, Christos, et al.
(författare)
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Incidence of tonsillar cancer in northern Sweden : Impact of human papilloma virus
- 2015
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Ingår i: Oncology Letters. - : Spandidos Publications. - 1792-1074 .- 1792-1082. ; 10:6, s. 3565-3572
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Tidskriftsartikel (refereegranskat)abstract
- The incidence rate of tonsillar cancer is increasing worldwide. The current study identifies a parallel increase in the incidence of tonsillar cancer, human papilloma virus (HPV) and p16 expression among a population from northern Sweden, a sparsely populated area, confirming the strong association between p16 and HPV infection in tonsillar tissue. Data from the Swedish Cancer Registry was assessed to identify cases of tonsillar cancer in the northern territorial area of Sweden. HPV DNA was extracted from paraffin embedded diagnostic biopsies and detected by polymerase chain reaction using general primers Gp5+/6+ and CpI/IIG. Expression of p16 was identified by immunochemistry. Patients were grouped into urban or rural residence categories. A total of 214 cases were identified, comprising 155 (72.4%) men and 59 (27.6%) women, and 65 of these patients, who presented between 2000 and 2012, were analyzed. The overall median age for the analyzed patients was 58 years; 48 (74%) were males (median age, 57.5 years) and 17 (26%) were females (median age, 65 years). Of the 65 specimens, 59 (91%) were positive for HPV, and 62 (95%) expressed p16. The incidence of tonsillar cancer in the cohort demonstrated a 2-fold increase between 1990 and 2013; specifically, a 2.7-fold increase was observed in men whilst the female group exhibited only a small increase. These findings demonstrate a strong association between p16 expression and HPV infection in tonsillar malignancies. The incidence of HPV-positive tonsillar cancer has increased in recent years, even in sparsely populated regions, as demonstrated in northern Sweden.
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| 13. |
- Lyon, Helen N., et al.
(författare)
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The association of a SNP upstream of INSIG2 with body mass index is reproduced in several but not all cohorts
- 2007
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Ingår i: PLoS Genetics. - : Public Library of Science (PLoS). - 1553-7404. ; 3:4
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Tidskriftsartikel (refereegranskat)abstract
- A SNP upstream of the INSIG2 gene, rs7566605, was recently found to be associated with obesity as measured by body mass index (BMI) by Herbert and colleagues. The association between increased BMI and homozygosity for the minor allele was first observed in data from a genome-wide association scan of 86,604 SNPs in 923 related individuals from the Framingham Heart Study offspring cohort. The association was reproduced in four additional cohorts, but was not seen in a fifth cohort. To further assess the general reproducibility of this association, we genotyped rs7566605 in nine large cohorts from eight populations across multiple ethnicities (total n = 16,969). We tested this variant for association with BMI in each sample under a recessive model using family-based, population-based, and case-control designs. We observed a significant (p < 0.05) association in five cohorts but saw no association in three other cohorts. There was variability in the strength of association evidence across examination cycles in longitudinal data from unrelated individuals in the Framingham Heart Study Offspring cohort. A combined analysis revealed significant independent validation of this association in both unrelated (p = 0.046) and family-based (p = 0.004) samples. The estimated risk conferred by this allele is small, and could easily be masked by small sample size, population stratification, or other confounders. These validation studies suggest that the original association is less likely to be spurious, but the failure to observe an association in every data set suggests that the effect of SNP rs7566605 on BMI may be heterogeneous across population samples.
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| 14. |
- Medina-Gomez, C., et al.
(författare)
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Life-Course Genome-wide Association Study Meta-analysis of Total Body BMD and Assessment of Age-Specific Effects
- 2018
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Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297. ; 102:1, s. 88-102
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Tidskriftsartikel (refereegranskat)abstract
- Bone mineral density (BMD) assessed by DXA is used to evaluate bone health. In children, total body (TB) measurements are commonly used; in older individuals, BMD at the lumbar spine (LS) and femoral neck (FN) is used to diagnose osteoporosis. To date, genetic variants in more than 60 loci have been identified as associated with BMD. To investigate the genetic determinants of TB-BMD variation along the life course and test for age-specific effects, we performed a meta-analysis of 30 genome-wide association studies (GWASs) of TB-BMD including 66,628 individuals overall and divided across five age strata, each spanning 15 years. We identified variants associated with TB-BMD at 80 loci, of which 36 have not been previously identified; overall, they explain approximately 10% of the TB-BMD variance when combining all age groups and influence the risk of fracture. Pathway and enrichment analysis of the association signals showed clustering within gene sets implicated in the regulation of cell growth and SMAD proteins, overexpressed in the musculoskeletal system, and enriched in enhancer and promoter regions. These findings reveal TB-BMD as a relevant trait for genetic studies of osteoporosis, enabling the identification of variants and pathways influencing different bone compartments. Only variants in ESR1 and close proximity to RANKL showed a clear effect dependency on age. This most likely indicates that the majority of genetic variants identified influence BMD early in life and that their effect can be captured throughout the life course. © 2017 American Society of Human Genetics
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| 15. |
- Mickelsson, Malin, et al.
(författare)
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ABO blood groups, RhD factor and their association with subclinical atherosclerosis assessed by carotid ultrasonography
- 2024
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Ingår i: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 13:5
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Tidskriftsartikel (refereegranskat)abstract
- Background: The ABO blood group system has previously been associated with cardiovascular disease (CVD), where non-O blood group individuals have shown an increased risk. Studies assessing early atherosclerotic disease while also including RhD are few. We aimed to determine whether the ABO and RhD blood groups are associated with subclinical atherosclerosis in a healthy population.Methods: We included 3532 participants from the VIPVIZA trial with available carotid ultrasonography results to assess subclinical disease. Information about blood groups was obtained from the SCANDAT-3 database, where 85% of VIPVIZA participants were registered.Results: RhD− individuals aged 40 years showed increased carotid intima–media thickness (B 1.09 CI 95% 1.03; 1.14) compared to RhD+ individuals. For ABO, there were no differences in ultrasonography results when assessing the whole study population. However, 60-year-old individuals with heredity for CVD and a non-O blood group had decreased odds for carotid plaques (OR 0.54 CI 95% 0.33; 0.88).Conclusions: RhD blood group is associated with subclinical atherosclerosis in younger individuals, indicating a role as a mediator in the atherosclerotic process. In addition, a non-O blood group was associated with decreased subclinical atherosclerosis in individuals aged 60 and with heredity (corresponding to the group with the highest atherosclerotic burden).
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| 16. |
- Mickelsson, Malin, et al.
(författare)
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Smoking tobacco is associated with renal hyperfiltration
- 2021
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Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : Taylor & Francis. - 0036-5513 .- 1502-7686. ; 81:8, s. 622-628
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Tidskriftsartikel (refereegranskat)abstract
- Tobacco consumption is a renal risk factor, but the effects on the estimated glomerular filtration rate (eGFR) remain unclear. We aimed to evaluate the possible impact of using tobacco products (smoking and snus) on eGFR based on creatinine or cystatin C. We used a first cohort with 949 participants and a second cohort with 995 participants; none had pre-existing renal disease. All subjects donated a blood sample and completed a questionnaire, including questions about tobacco use. To assess the effect on eGFR, hierarchical multiple linear regression models were used. Active smoking associated independently with a higher eGFRcreatinine in all subjects (p < 0.001; β = 0.11). Further analyses stratified for sex, showed similar findings for men (p < 0.001; β = 0.14) and for women (p = 0.026; β = 0.10). eGFRcystatin C was significantly associated with active smoking in all subjects (p = 0.040; β = −0.05), but no association was seen after stratification for sex. Snus did not associate with eGFR. In conclusion, smoking associated significantly with a higher eGFRcreatinine. The mechanism may be renal hyperfiltration of smaller molecules such as creatinine. This is probably caused by substances from smoked tobacco other than nicotine, as no effect was seen for snus.
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| 17. |
- Nilsen, Tom Ole, et al.
(författare)
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EFFECTS OF ANDROGENS AND CORTISOL ON GILL ION TRANSPORTERS AND OMSMOREGULATORY CAPACITY IN ATLANTIC SALMON (SALMO SALAR)
- 2014
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Ingår i: ICBF 2014, Edinburgh.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Sex steroids have been reported to compromise ion homeostasis in teleosts, yet there is limited and somewhat contradicting knowledge about the mechanisms through which androgens impact osmoregulatory capacity in salmonids. Immature Atlantic salmon post-smolts in seawater (SW) were injected with 11-ketoandrostenedione (OA; 25 µg/g BW), cortisol (F; 25 µg/g BW), F+OA (25 µg/g BW) and sham control (CON). After 8 days treatment, androgen treated fishdemonstrated a striking transcriptional increase in freshwater (FW)-type of ion transporters (NKA α1a ) , concurrent with no apparent ion perturbations, or down regulation of SW gill ion-transporters (NKA α1b). F treated post-smolts displayed increased gill NKA α1a transcription, with an additive effect of F+OA.. Moreover, F also resulted in decreased transcription of NKA α1b whilst fish treated with combinations of F and OA experienced severe ion perturbations and mortalities in SW, while no mortality occurred when only F was administered. Our findings suggests that androgens have, either directly or indirectly, a role in remodelling the gill epithelia for FW entry, rather than leading to osmoregulatory dysfunction in SW acclimated post-smolts. Moreover, maturing post-smolts may be sensitive to stress since combinations of elevated androgens and cortisol levels may have detrimental effects on homeostasis and fish welfare.
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| 18. |
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| 19. |
- Oda, Husam, 1975-
(författare)
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Leucine-rich repeats and immunoglobulin-like domain (LRIG) proteins : possible prognostic markers in vulvar squamous cell carcinoma, endometrial carcinoma, and oropharymgeal squamous cell carcinoma
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The human leucine-rich repeats and immunoglobulin-like domain (LRIG) gene family comprises three genes, LRIG1, LRIG2 and LRIG3, which encode the LRIG1, LRIG2 and LRIG3 proteins, respectively. Previous stidies have revealed the different prognostic roles of these proteins in different cancers, and it has been shown that LRIG1 functions as a tumour suppressor in certain cancers via its negative regulation of several receptor tyrosine kinases. Much less is known about the functionof LRIG2 and LRIG3. The expression of all three LRIG genes has been studied with human papillomavirus (HPV). In particular, expression of LRIG1 has been associated with improved survival in cervical, vaginal, and oropharyngeal cancers. Since LRIG1 has been shown to predict sensitivity to paltinum-based chemotherapy when studied in different cell lines, the possible role of LRIG protein expression in HPV-associated and other cancers may be interesting to investigate furthur.The overall aim of this thesis was to evaluate the immunoreactivity of LRIGs in vulvar squamous cell carcinoma (VSCC), endometrial carcinoma (EC) and oropharyngeal squamous cell carcinoma (OPSCC) and to investigate the potential prognostic value of LRIG proteins in association with HPV and p16 status in VSCC and OPSCC and to investigate the possible prognostic value of LMO7 and other prognostic markers of interest. Expression of the LRIG proteins and other markers was evaluated with immunohistochemistry, and HPV status was determined by PCR.In VSCC, high immunoreactivity of LRIG2 and LMO7 was associated with good survival. LRIG1 was not a significant prognostic factor in VSCC. We also conducted a pilot study to evaluate the immunoreactivity of LRIG proteins in 75 women with EC. Most of the patients in this cohort had very high positivity for LRIG proteins. High expression of LRIG3 was associated with better survival. LRIG1 and LRIG2 expression in tumours had no impact on prognosis in this study, but this should be interpreted with great caution due to the limited size of the cohort. Finally, high expression of LMO7 was associated with improved survival in OPSCC. In this cohort of 143 patients, LRIG1 expression was associated with worse survival in HPV-driven tumours. This is in contrast to previous published work where high LRIG1 expression has been associated with good survival. Notably, in both the VSCC and OPSCC cohort, a new polyclonal LRIG1 antibody was used in contrast to that in a previous study of OPSCC.In conclusion, we report additional data on the prognosticvalue of LRIG proteins in smaller cohort of VSCC, EC and OPSCC and suggest that these molecular markers need to be investigated furthur to elucidate possible clinical implications. In addition, a new monoclonal antibody against LRIG1 needs to be developed to ensure the reproducibility of the data.
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| 20. |
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| 21. |
- Palmer, Nicholette D, et al.
(författare)
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A genome-wide association search for type 2 diabetes genes in African Americans.
- 2012
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Ingår i: PloS one. - San Francisco : Public Library of Science (PLoS). - 1932-6203. ; 7:1, s. e29202-
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Tidskriftsartikel (refereegranskat)abstract
- African Americans are disproportionately affected by type 2 diabetes (T2DM) yet few studies have examined T2DM using genome-wide association approaches in this ethnicity. The aim of this study was to identify genes associated with T2DM in the African American population. We performed a Genome Wide Association Study (GWAS) using the Affymetrix 6.0 array in 965 African-American cases with T2DM and end-stage renal disease (T2DM-ESRD) and 1029 population-based controls. The most significant SNPs (n = 550 independent loci) were genotyped in a replication cohort and 122 SNPs (n = 98 independent loci) were further tested through genotyping three additional validation cohorts followed by meta-analysis in all five cohorts totaling 3,132 cases and 3,317 controls. Twelve SNPs had evidence of association in the GWAS (P<0.0071), were directionally consistent in the Replication cohort and were associated with T2DM in subjects without nephropathy (P<0.05). Meta-analysis in all cases and controls revealed a single SNP reaching genome-wide significance (P<2.5×10(-8)). SNP rs7560163 (P = 7.0×10(-9), OR (95% CI) = 0.75 (0.67-0.84)) is located intergenically between RND3 and RBM43. Four additional loci (rs7542900, rs4659485, rs2722769 and rs7107217) were associated with T2DM (P<0.05) and reached more nominal levels of significance (P<2.5×10(-5)) in the overall analysis and may represent novel loci that contribute to T2DM. We have identified novel T2DM-susceptibility variants in the African-American population. Notably, T2DM risk was associated with the major allele and implies an interesting genetic architecture in this population. These results suggest that multiple loci underlie T2DM susceptibility in the African-American population and that these loci are distinct from those identified in other ethnic populations.
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| 22. |
- Stefansson, Kristina, et al.
(författare)
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Activation of proteinase-activated receptor-2 by human kallikrein-related peptidases
- 2008
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Ingår i: Journal of Investigative Dermatology. - : Elsevier. - 0022-202X .- 1523-1747. ; 128:1, s. 18-25
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Tidskriftsartikel (refereegranskat)abstract
- Proteinase-activated receptor-2 (PAR2) is a seven transmembrane spanning, G-protein-coupled receptor, present on the membrane of many cell types including keratinocytes. In skin, PAR2 is suggested to play a regulatory role during inflammation, epidermal barrier function, and pruritus. PAR2 is activated by trypsin-like proteases by a unique mechanism where cleavage of the receptor leads to the release of a small peptide, which activates the receptor as a tethered ligand. The endogenous activators of PAR2 on keratinocytes have not been identified as of yet. Potential candidates are kallikrein-related peptidases (KLKs) expressed by epidermal cells. Therefore, the ability of four human skin-derived KLKs was examined with regard to their capacity to activate PAR2 in vitro. PAR2 cleavage was followed by immunofluorescence analysis and functional activation by measurements of changes in intracellular calcium levels. We found that KLK5 and KLK14, but neither KLK7 nor KLK8, induced PAR2 signalling. We conclude that certain, but not all, epidermal KLKs are capable of activating PAR2. We could also show the coexpression of KLK14 and PAR2 receptor in inflammatory skin disorders. These in vitro results suggest that KLKs may take part in PAR2 activation in the epidermis and thereby in PAR2-mediated inflammatory responses, including epidermal barrier repair and pruritus. The role of KLKs in PAR2 activation in vivo remains to be elucidated.
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| 23. |
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| 24. |
- Stefansson, Kristina, 1979-
(författare)
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Kallikrein-related peptidases in human epidermis : studies on activity, regulation, and function
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Introduction. The outermost layer of the epidermis, the stratum corneum (SC), plays a fundamental role in our defense against microorganisms, chemicals, and dehydration. The SC is composed of tightly packed keratinized skin cells, corneocytes. For a functioning skin it is essential that corneocytes are constantly shed (desquamated). Kallikrein-related peptidase (KLK) 5 and KLK7 may be important in the desquamation process through degradation of desmosomal proteins. Severe hereditary diseases, where inhibition of KLK5 and/or KLK7 is missing, points to the importance of regulation of protease activity. KLKs may be regulated in various ways: tissue expression, activation of proforms, specific inhibitors, and physico-chemical properties like pH. Besides their involvement in desquamation, KLKs may also be important in immune defense and inflammation by processing of mediators and via activation of proteinase-activated receptors (PARs). Aims. 1. To identify and characterize previously unknown proteases in the SC. 2. To further characterize KLK5 and KLK7 with special focus on activation mechanisms. 3. To identify new inhibitors of KLKs in human SC. 4. To further characterize KLKs regarding effects of various inhibitors and substrates. 5. To study possible functions of KLKs in inflammation, in particular via activation of PAR-2. Methods. Plantar SC was used as a source for purification of proteins. Recombinant proteins were produced in different expression systems (insect cells, yeast cells, and bacteria). Different activity assays and kinetic studies were performed. Tissue expression was studied by immunohistochemistry, immunoblot and PCR. PAR-2 activation was studied by measurement of intracellular [Ca2+] and immunofluorescense in KNRK-PAR2 cells. Results. Active KLK14 was purified from extracts of plantar SC. KLK14 showed a superior catalytic efficiency as compared to KLK5 when measuring trypsin-like activity. This indicated that KLK14, despite being present in low amounts in skin, may have great relevance for skin physiology. Among enzymes tested only KLK5 showed autocatalytic activity and is so far the only enzyme found in SC that can activate proKLK7. KLK5 could also activate proKLK14. This together with studies of pH dependence on activation placed KLK5 as a possible key activating enzyme in a proposed proteolytic cascade in the SC. In plantar SC extracts we have also identified the novel Kazal-type serine protease inhibitor 9 (SPINK9). Our results indicate that SPINK9 is preferentially expressed in palmo-plantar skin and specific for KLK5. Differences found regarding substrate specificity and inhibition profile can be useful in evaluating the contribution of individual KLKs to the proteolytic activity in crude SC extracts. One interesting finding was that KLK8, present at high protein levels in the epidermis, could not be inhibited by any protease inhibitor found in the extracts. PAR-2 activation studies showed that KLK5 and 14 but neither KLK7 nor 8 can activate PAR-2. Immunohistochemistry preferentially detected KLK14 in intraepidermal parts of the sweat ducts and in dermal sweat glands but we could also show coexpression of KLK14 and PAR-2 in the SC and stratum granulosum of the epidermis in inflammatory skin disorders. To summarize, KLK involvement in desquamation may be dependent on a proteolytic activation cascade regulated by an intrinsic pH gradient and specific inhibitors present in SC. Another possible function of KLKs is as mediators of inflammation through activation of PAR-2.
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| 25. |
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| 26. |
- Stefansson, Kristina, et al.
(författare)
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LRIG1‑2 and LMO7 immunoreactivity in vulvar squamous cell carcinoma : association with prognosis in relation to HPV‑DNA and p16INK4a status
- 2019
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Ingår i: Oncology Reports. - : Spandidos Publications. - 1021-335X .- 1791-2431. ; 42:1, s. 142-150
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Tidskriftsartikel (refereegranskat)abstract
- The present study was conducted to investigate the possible prognostic value of molecular markers LRIG1‑2 and LIM domain 7 protein (LMO7) in vulvar squamous cell carcinoma (VSCC) and their possible correlation to human papilloma virus (HPV)‑ and p16INK4a‑status of the tumors. Patients diagnosed with VSCC at the University Hospital of Umeå, Sweden, during the years 1990‑2013 were selected. Tumor blocks were retrieved from tissue archives and clinical data were collected from the records of patients. HPV‑PCR analysis, HPV genotyping and immunohistochemistry were performed. In total, 112 patients were included. Forty percent of the tumors were HPV‑positive, 27% were p16INK4a‑positive and 23% were positive for both HPV and p16INK4a (considered HPV‑driven). HPV‑positivity and p16INK4a‑positivity were associated with prolonged disease‑free survival (DFS) in Kaplan‑Meier survival analysis. Leucine‑rich repeats and immunoglobulin‑like domains 1 (LRIG1) immunoreactivity was not significantly associated with survival. High leucine‑rich repeats and immunoglobulin‑like domains 2 (LRIG2) immunoreactivity was associated with a prolonged overall survival (OS) (P=0.001). By analyzing HPV‑negative cases only, it was determined that high LRIG2 immunoreactivity was associated with both favorable OS (P=0.008) and DFS (P=0.031). LRIG2 immunoreactivity was also an independent prognostic factor in multivariate analysis of OS (P=0.002, HR=0.41; 95% CI, 0.24‑0.71). High immunoreactivity with LMO7‑1250 antibody was associated with survival benefits in the whole cohort (OS; P=0.011) although DFS was only prolonged in HPV‑negative and not HPV‑driven tumors (P=0.038 and 0.042, respectively). The present study indicated that LRIG2 and LMO7 may be useful prognostic markers in VSCC, particularly for patients without HPV‑driven tumors or with advanced tumors at diagnosis. In contrast to earlier observations regarding other types of squamous cell carcinoma, LRIG1 was not a significant prognostic factor in VSCC.
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| 27. |
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| 28. |
- Sundh, Henrik, 1976, et al.
(författare)
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Development of intestinal ion-transporting mechanisms during smoltification and seawater acclimation in Atlantic salmon Salmo salar
- 2014
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Ingår i: Journal of Fish Biology. - : Wiley. - 0022-1112. ; 85:4, s. 1227-1252
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Tidskriftsartikel (refereegranskat)abstract
- This study investigated the expression of ion transporters involved in intestinal fluid absorption and presents evidence for developmental changes in abundance and tissue distribution of these transporters during smoltification and seawater (SW) acclimation of Atlantic salmon Salmo salar. Emphasis was placed on Na+, K+-ATPase (NKA) and Na+, K+, Cl- co-transporter (NKCC) isoforms, at both transcriptional and protein levels, together with transcription of chloride channel genes. The nka alpha 1c was the dominant isoform at the transcript level in both proximal and distal intestines; also, it was the most abundant isoform expressed in the basolateral membrane of enterocytes in the proximal intestine. This isoform was also abundantly expressed in the distal intestine in the lower part of the mucosal folds. The protein expression of intestinal Nka alpha 1c increased during smoltification. Immunostaining was localized to the basal membrane of the enterocytes in freshwater (FW) fish, and re-distributed to a lateral position after SW entry. Two other Nka isoforms, alpha 1a and alpha 1b, were expressed in the intestine but were not regulated to the same extent during smoltification and subsequent SW transfer. Their localization in the intestinal wall indicates a house-keeping function in excitatory tissues. The absorptive form of the NKCC-like isoform (sub-apically located NKCC2 and/or Na+, Cl(-)co-transporter) increased during smoltification and further after SW transfer. The cellular distribution changed from a diffuse expression in the sub-apical regions during smoltification to clustering of the transporters closer to the apical membrane after entry to SW. Furthermore, transcript abundance indicates that the mechanisms necessary for exit of chloride ions across the basolateral membrane and into the lateral intercellular space are present in the form of one or more of three different chloride channels: cystic fibrosis transmembrane conductance regulator I and II and chloride channel 3.
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| 29. |
- Sundh, Henrik, 1976, et al.
(författare)
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NUTRIENT ABSORPTION IN THE ATLANTIC SALMON (SALMO SALAR L.) INTESTINE IS AFFECTED BY ENVIRONMENTAL SALINITY
- 2014
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Ingår i: ICBF 2014, Edinburgh.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Na+/K+-ATPases (NKA) located in the basolateral membrane of the intestinal absorptive cells (enterocytes) are the main driving force for both ion-coupled intestinal fluid transport and nutrient absorption in Atlantic salmon in seawater. It is hypothesized that a decreased need for osmoregulation in brackish water may be beneficial for the nutrient uptake and thereby the growth of the fish. Atlantic salmon post-smolts were acclimated to freshwater (FW), 12, 22 and 34 ppt seawater (SW) for several months. The intestinal nutrient transport (L-lysine and D-glucose) was measured in Ussing chambers and separate fish were used for intestinal mRNA expression of selected ion and nutrient transporters. No differences were found in mRNA levels of the NKA-α1c, NKCC2 co-transporter or SGLT-1 in relation to salinity, whereas the specific high-affinity low capacity Na+-coupled nutrient transport was significantly higher in FW and 22 ppt as compared to the 34 ppt group. The results suggest an allocation of the electrochemical gradient towards ion driven fluid transport in full strength SW.
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| 30. |
- Voight, Benjamin F., et al.
(författare)
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Twelve type 2 diabetes susceptibility loci identified through large-scale association analysis
- 2010
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 42:7, s. 579-589
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Tidskriftsartikel (refereegranskat)abstract
- By combining genome-wide association data from 8,130 individuals with type 2 diabetes (T2D) and 38,987 controls of European descent and following up previously unidentified meta-analysis signals in a further 34,412 cases and 59,925 controls, we identified 12 new T2D association signals with combined P < 5 x 10(-8). These include a second independent signal at the KCNQ1 locus; the first report, to our knowledge, of an X-chromosomal association (near DUSP9); and a further instance of overlap between loci implicated in monogenic and multifactorial forms of diabetes (at HNF1A). The identified loci affect both beta-cell function and insulin action, and, overall, T2D association signals show evidence of enrichment for genes involved in cell cycle regulation. We also show that a high proportion of T2D susceptibility loci harbor independent association signals influencing apparently unrelated complex traits.
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| 31. |
- Widbom, Lovisa, 1994-
(författare)
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Lifestyle, biomarkers and the risk of developing inflammatory bowel disease
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD), is a chronic disease causing inflammation in the gut mucosa. The pathogenesis involves alteration in gut microbiota and in the intestinal barrier due to genetic factors, environmental exposure and dysregulation of the immune response. Several environmental risk factors and risk genes have been identified, but still, the pathogenesis is not fully understood. Methods: Included papers are all case-control studies based on previously collected data stored with the biobank in Umeå, Sweden. Cases are individuals that participated in the Northern Sweden Health and Disease Study (NSHDS) at least one year before developing IBD. Information was available for all cases regarding age, time and place for inclusion in NSHDS, height and weight, sex and tobacco use. Part of the cases also had available data from a detailed food-frequency questionnaire. For each available case, controls matched for age, sex and time and place were selected. Analysed factors included tobacco use, with smoking and snuff use analysed separately), cotinine (a metabolite of nicotine), iron status (including ferritin, iron, transferrin and transferrin saturation), B-vitamins and tryptophan metabolites. Results: Smoking was associated with an increased risk of developing IBD both based on questionnaire data and using cotinine as a marker for exposure. Snuff use was not associated with risk for developing IBD. A lower ferritin was associated with an increased risk of developing IBD, whereas no association was seen for other iron status analytes. When analysing iron deficiency based on ferritin and CRP, it was shown that iron deficiency was more common among men before onset of IBD, whereas no difference was seen for women. Active vitamin B6 was lower among cases compared to controls, as well as an index indicating functional B6 deficiency. Kynurenic acid and xanthurenic acid, both tryptophan metabolites with immunomodulatory properties, were lower among cases than controls. For CD only, picolinic acid was lower among cases later developing IBD.Discussion: Smoking increases the risk of developing both UC and CD. Snuff use did not increase the risk for IBD, indicating that tobacco exposure is not the reason for increased IBD risk. Low ferritin indicates an early pathological process affecting iron storage unrelated to inflammation. Changes in vitamin B6 and tryptophan metabolites might indicate early pathological processes possibly related to gut microbiota changes. To conclude, this dissertation shows that multiple differences between individuals later developing IBD and controls can be seen years before IBD diagnosis. Some of which give insight to early pathophysiology in IBD.
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| 32. |
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| 33. |
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| 34. |
- Zeggini, Eleftheria, et al.
(författare)
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Meta-analysis of genome-wide association data and large-scale replication identifies additional susceptibility loci for type 2 diabetes
- 2008
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 40:5, s. 638-645
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Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association (GWA) studies have identified multiple loci at which common variants modestly but reproducibly influence risk of type 2 diabetes (T2D)(1-11). Established associations to common and rare variants explain only a small proportion of the heritability of T2D. As previously published analyses had limited power to identify variants with modest effects, we carried out meta-analysis of three T2D GWA scans comprising 10,128 individuals of European descent and similar to 2.2 million SNPs (directly genotyped and imputed), followed by replication testing in an independent sample with an effective sample size of up to 53,975. We detected at least six previously unknown loci with robust evidence for association, including the JAZF1 (P=5.0 x 10(-14)), CDC123-CAMK1D (P=1.2 x 10(-10)), TSPAN8-LGR5 (P=1.1 x 10(-9)), THADA (P=1.1 x 10(-9)), ADAMTS9 (P=1.2 x 10(-8)) and NOTCH2 (P=4.1 x 10(-8)) gene regions. Our results illustrate the value of large discovery and follow-up samples for gaining further insights into the inherited basis of T2D.
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| 35. |
- Zheng, Hou-Feng, et al.
(författare)
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Whole-genome sequencing identifies EN1 as a determinant of bone density and fracture
- 2015
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 526:7571, s. 112-
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Tidskriftsartikel (refereegranskat)abstract
- The extent to which low-frequency (minor allele frequency (MAF) between 1-5%) and rare (MAF <= 1%) variants contribute to complex traits and disease in the general population is mainly unknown. Bone mineral density (BMD) is highly heritable, a major predictor of osteoporotic fractures, and has been previously associated with common genetic variants(1-8), as well as rare, population specific, coding variants(9). Here we identify novel non-coding genetic variants with large effects on BMD (n(total) = 53,236) and fracture (n(total) = 508,253) in individuals of European ancestry from the general population. Associations for BMD were derived from whole-genome sequencing (n = 2,882 from UK10K (ref. 10); a population-based genome sequencing consortium), whole-exome sequencing (n = 3,549), deep imputation of genotyped samples using a combined UK10K/1000 Genomes reference panel (n = 26,534), and de novo replication genotyping (n = 20,271). We identified a low-frequency non-coding variant near a novel locus, EN1, with an effect size fourfold larger than the mean of previously reported common variants for lumbar spine BMD8 (rs11692564(T), MAF51.6%, replication effect size510.20 s.d., P-meta = 2 x 10(-14)), which was also associated with a decreased risk of fracture (odds ratio = 0.85; P = 2 x 10(-11); ncases = 98,742 and ncontrols = 409,511). Using an En1cre/flox mouse model, we observed that conditional loss of En1 results in low bone mass, probably as a consequence of high bone turnover. We also identified a novel low frequency non-coding variant with large effects on BMD near WNT16 (rs148771817(T), MAF = 1.2%, replication effect size +10.41 s.d., P-meta = 1 x 10(-11)). In general, there was an excess of association signals arising from deleterious coding and conserved non-coding variants. These findings provide evidence that low-frequency non-coding variants have large effects on BMD and fracture, thereby providing rationale for whole-genome sequencing and improved imputation reference panels to study the genetic architecture of complex traits and disease in the general population.
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| 36. |
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| 37. |
- Zillikens, M. C., et al.
(författare)
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Large meta-analysis of genome-wide association studies identifies five loci for lean body mass
- 2017
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 8:1
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Tidskriftsartikel (refereegranskat)abstract
- Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p < 5 x 10(-8)) or suggestively genome wide (p < 2.3 x 10(-6)). Replication in 63,475 (47,227 of European ancestry) individuals from 33 cohorts for whole body lean body mass and in 45,090 (42,360 of European ancestry) subjects from 25 cohorts for appendicular lean body mass was successful for five single-nucleotide polymorphisms in/ near HSD17B11, VCAN, ADAMTSL3, IRS1, and FTO for total lean body mass and for three single-nucleotide polymorphisms in/ near VCAN, ADAMTSL3, and IRS1 for appendicular lean body mass. Our findings provide new insight into the genetics of lean body mass.
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